Regulation of adrenal ornithine decarboxylase by adrenocorticotropic hormone and cyclic AMP. Adrenal ornithine decarboxylase activity was stimulated in a dose-related manner after administration of ACTH or dibutyryl ((6)N-2'-O-dibutyryl) cyclic AMP to hypophysectomized rats. Little effect was observed for 2 h, but striking increases in enzyme activity were observed 4 h after administration of these substances. Effects of ACTH and dibutyryl cyclic AMP were not secondary to stimulation of steroidogenesis, since hydrocortisone had no effect on adrenal ornithine decarboxylase although it did stimulate activity of the enzyme in the liver and kidney.ACTH, given subcutaneously to hypophysectomized rats, induced striking increases in adrenal cyclic AMP levels within 15-30 min with a fall towards the base line in 1 h. Increases in ornithine decarboxylase activity lag several hours after this endogenous cyclic AMP peak, in contrast to the stimulatin of steroidogenesis by the nucleotide that requires only 2-3 min. After graded doses of ACTH, increases in adrenal cyclic AMP levels at 30 min were paralleled by proportional increases in adrenal ornithine decarboxylase activity 4 h after hormone treatment. Whereas maximal levels of adrenal steroidogenesis have been observed at tissue cyclic AMP levels of 6 nmol/g. ACTH is capable of inducing increases in nucleotide levels up to 200 nmol/g or more. These high tissue levels of cyclic AMP, although unneccessary for maximal steroidogenesis, appear to stimulate adrenal ornithine decarboxylase activity. Several results in addition to the time lag in the stimulation of ornithine decarboxylase activity suggest a mechanism involving accumulation of the enzyme or some factor needed for its activity rather than direct activation of the enzyme by cyclic AMP. Thus, the addition of cyclic AMP directly to the ornithine decarboxylase assay mixture in vitro was without stimulatory effect. In addition, actinomycin D or cycloheximide in doses sufficient to block adrenal RNA and protein synthesis, respectively inhibited the stimulation of ornithine decarboxylase activity by ACTH in vivo. An adrenocortical cancer was found to maintain ornithine decarboxylase activity at very high levels, but did so at much lower cyclic AMP levels than those of ACTH-stimulated adrenals. It is concluded that ACTH stimulates adrenal ornithine decarboxylase activity and that this effect may be mediated by cyclic AMP. However, cyclic AMP be mediated by appear to be a determinant of the high level of enzyme activity found in adrenocortical cancer.


Development of intestinal adenyl cyclase and its response to cholera enterotoxin. Adenyl cyclase activity in intestinal membranes has been studied during development in the rabbit fetus from fetal day 17 to 10 days postnatally and in the human fetus from the 10th to the 17th wk of gestation. In the rabbit, the enzyme was already present by fetal day 17 and showed a fourfold peak rise in specific activity by 22 days. By 28 days, the specific activity had fallen toward adult levels and remained constant throughout gestation and the 1st wk of life. Fluoridestimulated activity showed a similar curve, and was 2.5-5 times the basal values. Activities in jejunum and ileum were comparable at all time points studied. Phosphodiesterase activity did not change during gestation. When fetal intestinal segments were incubated in vitro with purified cholera enterotoxin, adenyl cyclase activity in subsequently prepared membranes was increased two- to threefold. This level was not regularly further elevated by fluoride ion. Lithium ion inhibited both the basal and fluoride-stimulated enzyme activity in membranes prepared from rabbit fetuses at term. Lactase activity (reflecting the development of the microvilli) in either whole intestinal homogenates or in the membrane fractions showed a differnet pattern of development, with a rise beginning on fetal day 24 and a plateau just after birth. In intestinal membranes prepared from human fetuses, the activity of both basal and fluoride-stimulated adenyl cyclase tripled from the 10th to the 17th wk of gestation. The data both in the rabbit and in man show that intestinal adenyl cyclase is capable of responding to cholera enterotoxin quite early in gestation. In the rabbit, this occurs before the time of appearance or ville or of an enzyme marker (lactase) for microville. The results support the concept that adenyl cyclase is present in plasma membrane other than the brush border.


Disparate enzyme activity in erythocytes and leukocytes. A variant of hypoxanthine phosphoribosyl-transferase deficiency with an unstable enzyme. A family is reported in which each of two sisters has a son with no detectable hypoxanthine phosphoribosyltransferase (HPRT) (EC 2. 4. 2. 8) in his erythrocytes, a finding considered pathognomonic of Lesch-Nyhan disease. However, neither has the stigmata of the disease. One boy is neurologically normal, and the other is moderately retarded. There was only a slight increase in urinary uric acid, but the amounts of hypoxanthine and xanthine, and their ratios, were similar to those found in Lesch-Nyhan disease, strongly indicating that excesses of these last two oxypurines are not responsible for the symptomatology in that disease. In contrast to the nondetectable HPRT activity in the red blood cells, leukocyte lysates from the two boys have 10-15% of normal activity, possibly reflecting continuing synthesis of an unstable enzyme. This hypothesis is supported by the demonstration that at 4 degrees C HPRT activity was rapidly lost in the propositus while the activity increased in control subjects. The mother's cells were intermediate between the two. The intact and disrupted leukocytes of the hemizygote, in the absence of added phosphoribosyl converted as much hypoxanthine to inosinate as the normal cell, and appropriate tests indicated that under these circumstances enzyme concentration is not rate limiting whereas the concentration of the cosubstrate, phosphoribosyl pyrophosphate, is. The capacity for normal function in the intact mutant cell is more representative of in vivo conditions than the lysate, which may explain the important modification of clinical symptomatology, the relatively mild hyperuricosuria, and the presence of mosaicism in the circulating blood cells of the heterozygotes. A similar explanation may apply to other genetic diseases in which incomplete but severe enzyme deficiencies are found in clinically normal individuals. An associated deficiency in glucose-6-phosphate dehydrogenase in this family permitted confirmation of previous observations on linkage with hypoxanthine phosphoribosyltransferase.


Mutants of nonproducer cell lines transformed by murine sarcoma viruses. I. Induction, isolation, particle production, and tumorigenicity. A variety of cell mutants were obtained by a single 5'-bromodeoxyuridine (BrdU) treatment of an nonproducer (NP) cell line transformed by the Kirsten strain of murine sarcoma virus (Ki-MSV). Isolation procedures of these cell See PDF for Structure mutants are described. The cell mutants obtained were classified by tumorigenic potential and shedding of Type C virus particles. The cell mutants were classified into four groups: (A) tumorigenic, without particles; (B) tumorigenic, with Type C particles; (C) nontumorigenic, without particles; and (D) nontumorigenic, with Type C particles. The tumorigenic cell lines showed variability in morphology with both flat and typical transformed appearing cell lines showing equal transplantability.


The modulating influence of cyclic nucleotides upon lymphocyte-mediated cytotoxicity. The capacity of allosensitized thymus-derived lymphocytes to destroy target cells bearing donor alloantigens is modulated by the cellular levels of cyclic AMP and cyclic GMP. Increases in the cyclic AMP levels of attacking lymphocytes by stimulation with prostaglandin E(1), isoproterenol, and cholera toxin inhibit lymphocyte-mediated cytotoxicity; whereas, depletion of cyclic AMP with imidazole enhances cytotoxicity. The augmentation of cytotoxicity produced by cholinergic stimulation with carbamylcholine is not associated with alterations in cyclic AMP levels and is duplicated by 8-bromo-cyclic GMP. The effects of activators of adenylate cyclase, cholinomimetic agents, and 8-bromocyclic GMP are upon the attacking and not the target cells and occur at the time of initial interaction of attacking and target cells. Indeed, the level of cyclic nucleotide (cyclic AMP and cyclic GMP) at the time of initial cell-to-cell interaction determines the extent of cytotoxicity.


Observations on the microbiological flora of canned Parma ham. A significant proportion of a consignment of branded Parma Ham was found to have ;blown' tins; the associated bacterial flora was therefore investigated. No Salmonella or Shigella were found. Clostridium welchii type A and Clostridium bifermentans were isolated in moderate numbers only from enrichment cultures of the ham. Staphylococcus spp. and coryneform bacteria were obtained from all tins and Group D streptococci were present in a few. No food-poisoning cases were associated with this ham.


Lipid A: chemical structure and biological activity.


Immunologic and antineoplastic effects of endotoxin: role of membranes and mediation by cyclic adenosine-3',5'-monophosphate.


Petrographic study of the refractory performance of high-fusing dental alloy investments. II. Silica-bonded investments.


Radiotherapy of glioblastoma multiforme.


An experimental radiopaque composite material.


Effects of endotoxin on macrophages and other lymphoreticular cells.


Intravenous radionuclide hepatography in the differential diagnosis of intrahepatic mass lesions.


Evaluation of vitamin D supplements by biological assay using the turkey.


The in-vitro effects of silica-treated hamster macrophages on collagen production by hamster fibroblasts.


Triple carcinoma of the breast, one arising within a fibro-adenoma.


Androblastoma of the ovary with heterotopic elements.


Lactic dehydrogenase and other enzymes in the mouse uterus during the peri-implantation period of pregnancy.


Conservative management of the infected pacemaker pulse generator.


Secretion and uptake of peroxidase by rat adenohypophyseal cells.


Studies of the myocardial metabolism of free radicals in the myocardial infarction (with electron spin resonance (ESR) spectrometry).


Delayed dermal hypersensitivity to autologous lymphocytes in multiple sclerosis.


Nervous system lesions after sting by yellow jacket. A case report.


Myasthenia gravis lacking response to cholinergic drugs.


Vasopressin: possible role of microtubules and microfilaments in its action. Colchicine, vinblastine, podophyllotoxin, and cytochalasin B inhibit the action of vasopressin and cyclic adenosine monophosphate on osmotic water movement across the toad bladder. The findings suggest that microtubules, and possibly microfilaments, play a role in the action of vasopressin, perhaps through involvement in the mechanism of release of secretory material from the bladder epithelial cells.


Poliomyelitis vaccination of infants: preimmunization status and seroconversion. A study was carried out in Delhi on the preimmunization status of infants aged 2-6 months with regard to poliomyelitis and on seroconversion after the administration of oral poliomyelitis vaccine. It was found that 30.3% of the 204 infants included in the study excreted enteroviruses, 58% of which were found to be polioviruses. Of 197 sera examined for neutralizing antibodies against different types of poliovirus, 73% were found to be triple negative and only 4.0% triple positive. Three doses of oral poliomyelitis vaccine were administered at intervals of 1 month. It was found that 71.8% of the vaccinated infants excreted cytopathogenic agents in the 7 days following the first dose; 80.4% of these agents were found to be polioviruses. Seroconversion was studied in 71 infants, and good antibody responses to all three types of poliovirus were observed.


The second international reference preparation of viomycin. The first International Reference Preparation of Viomycin was replaced by the second international reference preparation, consisting of material from the batch that provided the second Working Standard of the US Food and Drug Administration. The International Unit of viomycin was redefined as the activity contained in 0.0012285 mg of the second international reference preparation. Examination of batches of viomycin sulfate from the various sources of production showed that the second international reference preparation was suitable for their assay, whereas a sample previously proposed as the international standard of viomycin was unsatisfactory.


Pyruvate carboxylase in the developing chick embryo.


Effect of pentagastrin on adult rat duodenal cells in culture.


Hepatic changes in adult alpha-1-antitrypsin deficiency.


Induction of tryptophan oxygenase in Cicer arietinum seedlings by indole-3-acetic acid & cyclic 3',5'-adenosine monophosphate.


Causes and prevention of colonic anastomotic breakdown.


Mechanisms of inhibition and activation of beef liver D-glycerate dehydrogenase by inorganic anions.


Kinetic studies on the G-factor-dependent uncoupled GTPase of ribosomes.


Isolation and characterization of glycopeptides from rat liver nuclear membrane.


Purification and some properties of G-factor from the silk gland of silkworm.


Effect of calcium ion on lipase-fat complex formation.


Studies on proteolytic enzymes (pronase) of Streptomyces griseus K-1. 3. Purification and proteolytic specificity of alkaline proteinase C from pronase.


DNA dependent RNA polymerase from Ehrlich ascites tumor cells. II. Factors stimulating the activity of RNA polymerase II.


Serum thyrotropin (TSH) in pituitary and-or hypothalamic hypothyroidism: normal or elevated basal levels and paradoxical responses to thyrotropin-releasing hormone.


Oat-cell carcinoma of the lung simultaneously producing ACTH and serotonin.


Adenocarcinoma of the colon associated with ureterosigmoidostomy: report of a case.


Maternal-fetal ACTH relationship in man.


Radioreceptor assay for growth hormone.

Radioreceptor assay for growth hormone.


Catecholamine transmitter for salivary secretion in the cockroach.


Neoplasm induction by murine type-C viruses passaged directly from spontaneous non-lymphoreticular tumours.


Gonadotropin and steroid hormone excretion in trophoblastic neoplasia.


Spontaneous regression of Bowenoid atypia of the vulva.


Metastatic and secondary tumors of the vulva.


A comparative evaluation of the distribution of concanavalin A-binding sites on the surfaces of normal, virally-transformed, and protease-treated fibroblasts. The topographical distributions of concanavalin A-binding sites on the surfaces of 3T3, proteasetreated 3T3, and simian virus 40-transformed 3T3 cultured mouse fibroblasts appear to be different, as shown by a shadow-cast replica technique using concanavalin A and a hemocyanin marker, or as shown previously on isolated membranes with concanavalin A coupled to ferritin. However, chemical fixation of cells before labeling with concanavalin A and hemocyanin, or labeling exclusively at 4 degrees , allows one to distinguish between inherent concanavalin A-binding-site topography and potential rearrangement of sites induced by the action of the multivalent concanavalin A molecule itself. The inherent distribution of binding sites on 3T3, protease-treated 3T3, and transformed cells is actually the same on all cells, i.e., dispersed and random. Treatment of unfixed transformed or protease-treated 3T3 cells, but not normal 3T3 cells, with concanavalin A and hemocyanin at 37 degrees (or at 4 degrees with subsequent warming to 37 degrees ), however, results in clustering of binding sites, presumably due to crosslinking of neighboring lectin-binding sites by the quadrivalent concanavalin A. Thus, the underlying difference between concanavalin A-binding sites on normal as compared with transformed or protease-treated normal cells lies not in the inherent topography of binding sites, but rather in the susceptibility of the sites to aggregation by concanavalin A. The latter may reflect an increased mobility of lectin-binding sites on transformed or protease-treated cells.


Response of Dictyostelium plasma membranes to adenosine 3':5'-cyclic monophosphate. Myxamoebae of the cellular slime mold Dicytostelium discoideum aggregate in response to a chemotactic substance identified as adenosine 3':5'-cyclic monophosphate. Upon aggregation cell division is suppressed, the cells become adhesive, and differentiation is initiated. Freeze-fracture studies of myxamoebae were conducted to determine the effect of cyclic AMP and calcium on plasma membrane ultrastructure. The inner surfaces of the plasma membranes exhibited particulate structures whose sizes (43-187 A) and frequency distribution were determined. Cyclic AMP and calcium induced within 2 hr the formation of particles having average diameters 1.7-times and 1.5-times greater, respectively, than those of the vegetative myxamoebae controls. These data suggest that cyclic AMP mobilizes the intracellular calcium which may be effective in changing plasma membrane structure.


"Early" virus-specific RNA may contain information necessary for chromosome replication and mitosis induced by Simian Virus 40. Simian Virus 40 (SV40) induces in "contact-inhibited" tissue culture cells of mouse kidney an abortive infection that leads to the appearance of intra-nuclear SV40-specific tumor (T-) antigen, followed by replication of the mouse-cell chromatin and mitosis, while no viral progeny DNA or capsid protein is produced. Synthesis of "early" SV40-specific RNA ("19S RNA") begins a few hours before the appearance of T-antigen and appears to be switched off after the onset of chromatin replication. As the most simple working hypothesis that can account for the experimental results available, we assume that early SV40 RNA contains information necessary for production of T-antigen and that this antigen (or an unknown early virus-specific function that would simply parallel the appearance of T-antigen) activates or de-inhibits a cellular regulatory element that governs chromosome replication and mitosis. The experimental results agree with the idea that SV40 acts primarily as a mitogen.


Pleiotypic control by cyclic AMP: interaction with cyclic GMP and possible role of microtubules. Previous studies have shown that exogenous dibutyryl cyclic AMP inhibits the uptake of uridine, leucine, and 2-deoxyglucose by cultured mouse fibroblasts. 3':5'-cyclic GMP is shown here to counteract these inhibitory effects as well as the inhibition of precursor transport and leucine incorporation into proteins produced by prostaglandin E(1). We conclude, therefore, that cyclic GMP antagonizes the "pleiotypic" effects of cyclic AMP in these cells. Colcemid and vinblastine, but not cytochalasin B, reverse the transport inhibition caused by cyclic AMP without affecting the intracellular concentrations of cyclic AMP. These results suggest the possibility that cyclic AMP regulates the membrane transport of certain substrates by influencing the organization of microtubules.


Cell contact-dependent increase in membrane D-galactopyranosyl-like residues on normal, but not virus- or spontaneously-transformed, murine fibroblasts. Ricinus communis agglutinin (a lectin specific for beta-D-galactopyranosyl-like oligosaccharide residues) was used to investigate differences in lectin-binding sites on normal 3T3 and transformed SV3T3 and 3T12 cells grown to various cell densities in culture. The agglutinability of SV3T3 cells by R. communis agglutinin decreased when cells were grown to confluency or to a point where the cells were in contact. The agglutinability of 3T3 cells also decreased at confluency, but this result was variable and not as dramatic as with SV3T3 cells. Saturation-binding experiments performed at 4 degrees with (125)I-labeled R. communis agglutinin were used to monitor the number of lectin-binding sites on cells grown to different densities. Transformed cells (SV3T3 and 3T12) did not show cell-culture density-dependent changes in R. communis sites; sparse, touching, and confluent transformed cells had equivalent numbers of sites. However, touching (or confluent) 3T3 cells possessed 2.5-times the number of R. communis sites per cell compared to growing, sparsely populated 3T3 cells. When growing sparse 3T3 cells are compared to growing SV3T3 or 3T12 cells, there are 5-times R. communis sites per unit surface area on the transformed cells. The change in R. communis sites during cell growth in culture is discussed in relation to membrane fluidity and topography of plasma membrane oligosaccharides and glycosyl transferases, which can modify cell surfaces at contact.


Reduction of ferricytochrome c by dithionite ion: electron transfer by parallel adjacent and remote pathways. The kinetics of the reduction of horseheart ferricytochrome c by sodium dithionite (phosphate buffer-sodium chloride; pH 6.5, mu = 1.0, 25 degrees ) features two reaction pathways; one with the rate constant k(3) = 1.17 x 10(4) M(-1) sec(-1), the other with the rate constant k(1)k(2)/k(-1) = 6.0 x 10(4) M(-1) sec(-1). These pathways are interpreted in terms of remote attack (possibly by way of the exposed edge of the porphyrin system) and adjacent attack (requiring the opening of the heme crevice). The limiting rate for the adjacent pathway (k(1) = 30 sec(-1)) is in good agreement with the rate of heme-crevice opening of ferricytochrome c determined in other studies. The implication of the adjacent attack pathway to the function of cytochrome c in vivo is discussed.


A general method of gene isolation.

A general method of gene isolation. A general method of gene isolation has been developed that involves the chemical linkage of RNA to cellulose by a water-soluble carbodiimide, and the continuous circulation of DNA containing specific sequences complementary to the RNA. The temperature of the cellulose matrix is maintained at 37 degrees (50% formamide, 0.3 M NaCl-0.03 M Na(3) citrate) to allow efficient DNA-RNA interaction in the stationary phase, while unreacted and any reassociated DNA is denatured at 90 degrees and then recirculated into the hybridization chamber. Between 40 and 45% of fragmented (32)P-labeled simian virus (SV)40 DNA was removed from the circulating solution when cellulosebound SV40-specific RNA, assymmetrically transcribed in vitro with Escherichia coli RNA polymerase, was used. In the presence of 10(4)-fold excess of sheared E. coli DNA, nearly half of the [(32)P]SV40 DNA was recovered from the mixture as a DNA-RNA hybrid with negligible contamination by bacterial DNA. The isolation procedure is almost quantitative for the complementary DNA. The efficiency and selectivity of this method permit the isolation of a defined DNA sequence from a large and complex genome.


A new enzymatic assay for guanosine 3':5'-cyclic monophosphate and its application to the ductus deferens of the rat. A sensitive enzymatic procedure has been developed for the determination of guanosine 3':5'-cyclic monophosphate (cyclic GMP). It is based on the conversion of cyclic GMP to GMP by cyclic nucleotide phosphodiesterase and on the transfer of (32)P from [gamma-(32)P]ATP to GMP by the action of a specific ATP:GMP phosphotransferase (EC 2.7.4.8). The [(32)P]GDP is separated from the remaining [(32)P]ATP by enzymatic degradation of ATP by myosin and by precipitation of the (32)P(i) formed. The reaction blank, which is mostly caused by the nucleotide content of the enzymes, is doubled by about 0.1 pmol of cyclic GMP. The procedure has advantages in speed and/or accuracy over other methods in current use. Cyclic nucleotide concentrations were studied in the ductus deferens of the rat; two agents were used, carbachol and norepinephrine, which cause contraction. Incubation with 0.1 mM carbachol caused a 3-fold increase in cyclic GMP content, which was maximal about 2 min after carbachol addition. Cyclic AMP concentrations were not significantly changed. Addition of 0.01 mM norepinephrine increased cyclic GMP content by about 25% within 1 min and by 40% within 3 min; cyclic AMP concentrations were only slightly increased. A 3-min incubation with the phosphodiesterase inhibitor 1-methyl-3-isobutylxanthine (0.1 mM) doubled the cyclic GMP content and increased cyclic AMP concentration by 50%.


Identification of a large polypeptide precursor of avian oncornavirus proteins. Antibody to partially disrupted avian myeloblastosis virus was used to selectively precipitate newly synthesized intracellular viral polypeptides from extracts of infected chicken cells. When analyzed by sodium dodecyl sulfate-gel electrophoresis, immune precipitates from extracts of cells pulse-labeled for 10 min with [(35)S]methionine contain none of the major virion polypeptides. Instead they show prominent viral specific polypeptides of molecular weight 76,000 and 12,000, as well as minor quantities of other labeled polypeptides. From pulse-chase kinetics and two-dimensional tryptic finger-prints it appears that the large polypeptide is a precursor of at least the two major virion proteins of molecular weights 24,000 and 11,000, while the smaller is a precursor of the 11,000-dalton virion protein.


Cytochalasin blocks sympathetic ganglionic transmission: a presynaptic effect antagonized by pyruvate. The mold metabolite cytochalasin B blocked transmission through the perfused superior cervical sympathetic ganglion of the cat. Acetylcholine injected close-arterially during block continued to excite the ganglion cells so that failure was presynaptic and, by inference, due to reduced output of acetylcholine from the preganglionic nerves. This blocking effect of cytochalasin was reduced by pyruvate. It is concluded that cytochalasin inhibits cholinergic nervous function and it does so, at least in part, by depressing energy production at some stage before pyruvate formation. One possibility is a block of glucose uptake for which there is evidence from other cell types. A more general conclusion is that inhibitory effects of cytochalasin on other secretory systems may also involve such a metabolic component and do not necessarily reflect an interaction of the drug with microfilaments as has been commonly supposed.


Membrane changes and adenosine triphosphate content in normal and malignant transformed cells. Transformed fibroblasts had a low content of ATP when grown at a high cell density and a high content of ATP when grown at a low cell density. Concanavalin A agglutinated transformed cells with a low, but not those with a high, ATP content. Transformed cells with a high ATP content gained agglutinability after ATP depletion by inhibitors of the energy-generating systems, and those with a low ATP content lost their agglutinability after restoration of a high ATP content by glucose. Fixation of the surface membrane by formaldehyde, glutaraldehyde, or LaCl(3), inhibited agglutination of cells with an ATP content that allows agglutination. Normal fibroblasts grown at a high or a low cell density were not agglutinated by concanavalin A. Depletion of the cellular ATP content of normal cells induced agglutination only in cells grown at a high, but not at a low, cell density. A similar number of concanavalin A molecules was bound to the surface membrane of agglutinating and nonagglutinating fibroblasts. It is suggested that a high content of ATP inhibits the movement of concanavalin A binding sites, and that a low content of ATP allows, in transformed cells, a new distribution of binding sites to form the clusters required for cell agglutination. Agglutinability of transformed cells is determined by ATP content, and in normal cells changes in the content of ATP are by themselves not sufficient to induce agglutination. Transformed cells, therefore, do not have a control, presumably for membrane stability, that exists in normal cells.


A temperature-sensitive change in the energy of activation of hormone-stimulated hepatic adenylyl cyclase. We describe an abrupt increase (at 32 degrees ) in the energy of activation for the reaction of hepatic adenylyl cyclase in the presence of glucagon or epinephrine. This increase is not seen in the presence of fluoride, prostaglandin E(1), or 1-propanol, or in the absence of cyclase stimulators. The change in energy of activation found with hormones is abolished by 1-propanol. This change does not represent differences in hormone or substrate binding at different temperatures, but seems to reflect interactions among elements of the cyclase stimulation sequence. Similar changes in energy of activation were not observed for alkaline phosphatase, cyclic AMP-phosphodiesterase, 5'-nucleotidase, or ouabain-sensitive ATPase. Since the mole fraction of cholesterol in liver membranes is sufficiently high to preclude a phase change in bulk membrane lipids, our observation suggests either that cyclase is restricted to cholesterol-poor membrane regions or that the change in its energy of activation is largely restricted to protein components of the cyclase apparatus. The data are compatible with fundamental differences in the stimulation process(es) for the hormones (glucagon and epinephrine) as compared with those for fluoride and prostaglandin E(1).


Activation by adenosine 3':5'-monophosphate of a membrane-bound phosphoprotein phosphatase from toad bladder. Adenosine 3':5'-monophosphate (cyclic AMP) caused a decrease in the net rate of incorporation of radioactive phosphate into a specific protein (protein D) in a membrane fraction from toad bladder. Moreover, when the membrane protein was prelabeled with radioactive phosphate, cyclic AMP caused an increase in the net rate of removal of radioactive phosphate from this specific protein. Certain agents were shown to be selective inhibitors of membrane-bound protein D kinase or protein D phosphatase. With the help of these agents, it was concluded that cyclic AMP caused the activation of membrane-bound protein D phosphatase. The present data, together with earlier studies, are compatible with the possibility that the cyclic AMP-induced activation of a membrane-bound phosphoprotein phosphatase in toad bladder, with the consequent dephosphorylation of protein D, may be responsible for the physiological effects of antidiuretic hormone on sodium and/or water transport in this tissue.


Spin-state correlations in near infrared spectroscopy of cytochrome c'. Characteristic absorption spectra in the ultraviolet, visible, and near infrared regions are correlated with spin state in ferriheme proteins. Weak, diffuse bands in the near infrared exhibit maxima at about 1000-1100 nm (high spin) and at about 1450-1750 nm (low spin). In these and earlier studies such correlations have been established for several ferriheme proteins, but less extensively than in the more well-known cases of Soret and visible band maxima. We have strengthened the correlation in the near infrared by measurements of absorption spectra in Rhodospirillum rubrum cytochrome c', a variant c-type cytochrome that exhibits a pH-induced transition from high-spin to low-spin state as the pH varies from 6.3 to 13.1. Data are provided on extinction coefficients of characteristic absorption bands at various pH values, obtained by comparison with those measured under the same conditions for horse-heart ferricytochrome c. It is concluded that good correlations of spin state with absorption behavior exist over the entire spectroscopic range from 250 to 2500 nm and that the basic assignments of absorption bands to in-plane charge transfer processes are consistent with these correlations.


Induction of lymphocyte transformation by sequential treatment with neuraminidase and galactose oxidase. Treatment of mouse-spleen cells with galactose oxidase (EC 1.1.3.9) after incubation with neuraminidase (EC 3.2.1.18) induced extensive blastogenesis. Treatment of the cells with galactose oxidase before incubation with neuraminidase had very little stimulatory effect. Either of these enzymes alone had practically no effect on the cells. The lymphocyte transformation induced by galactose oxidase in neuraminidase-treated cells was decreased upon reacting the cells with borohydride or hydroxylamine, whereas treatment with these compounds did not affect transformation of cells by concanavalin A. It is suggested that galactosyl residues exposed by the action of neuraminidase on the cell membrane are oxidized by galactose oxidase, and the aldehyde moiety thus formed is involved in the induction of blastogenesis.


Protein kinase activity in erythrocyte ghosts of patients with myotonic muscular dystrophy. Myotonic muscular dystrophy is a disorder of humans that involves many organ systems. Physiological studies have suggested that the fundamental defect is of membrane origin. Heretofore, no reproducible metabolic abnormalities have been demonstrated. In the present studies we used erythrocyte ghosts as a convenient source of purified membranes that do not possess changes of denervation, dystrophy, and fibrosis that might complicate the interpretation of muscle membrane changes. Our experiments demonstrated a significant difference in the phosphorylation of erythrocyte ghost protein by [gamma-(32)P]ATP, with endogenous protein kinase of erythrocyte membrane as the enzyme source. After ghosts were kept for 1 week at -20 degrees , phosphorylation of membrane protein in eight controls was twice as high as endogenous protein kinase activity measured in fresh preparations. No stimulation was seen in preparations from seven myotonic dystrophy patients from three different families. This reproducible difference in normal and myotonic membranes may represent an important new approach to studies of this debilitating inborn error of metabolism.


Glia-induced morphological differentiation in neuroblastoma cells. Glial cells release a factor into their culture medium that induces a high degree of morphological differentiation in neuroblastoma cells under normal growth conditions. This phenomenon is not correlated with a change in intracellular adenosine 3':5'-cyclic monophosphate or in the rate of cell growth. Media from other cell lines tested induce less morphological differentiation or have no effect.


Common cell-surface antigen associated with murine and feline C-type RNA leukemia viruses. A new common cell-surface antigen associated with murine and feline C-type RNA leukemia viruses was demonstrated by the use of rabbit antiserum against feline leukemia virus and the indirect membrane immunofluorescence test. Common cell-surface antigen was found in all leukemias of all strains of mice tested, in normal lymphoid tissues of Gross-positive (high incidence of leukemia) mouse strains AKR, AKR.H-2(b), C58, and NZB, in cultured rat fibroblasts infected with Rauscher virus, in cultured feline fibroblasts infected with feline leukemia virus, and in spontaneous feline lymphosarcoma. The antigen was not demonstrable in normal adult and fetal tissues of Gross-negative mouse strains or in tissues and cultured fibroblasts derived from normal rats and normal cats. The immunoferritin study of murine leukemia cells revealed that the antigen was located on the cell surface in discrete areas; budding and C-type RNA viral envelope was not labeled as antigen site. The distribution of common cell-surface antigen on murine and feline leukemias, as well as on normal lymphoid tissues of Gross-positive mouse strains, indicates the presence of an antigen distinct from any cell-surface antigen heretofore shown to be associated with, or specified by, mammalian C-type RNA viruses.


Detection and assessment of case clustering in Burkitt's lymphoma and Hodgkin's disease.


Primary carcinomas of the liver in Hong Kong: some possible aetiological factors.


Epidemiologic and immunologic considerations on the pathogenesis of Burkitt's Tumor.


Etiology of Burkitt's lymphoma.

Etiology of Burkitt's lymphoma.


Multiplicity of lung tumour classifications.


Histoenzymologic and biochemical investigations into the nervous tissue round an experimentally-induced cerebral hemorrhagic focus.


Investigation on the epidemiological significance of detailed cancer data--preliminary results.


Plasma lipoproteins and hyperlipoproteinemia.


Ophthalmoscopic findings and changes in hormonal and metabolic parameters in "protodiabetes".


Comparative metabolic and clinical studies of sexual ateliotic dwarfs and diabetics.


Kidney structural abnormalities in early diabetes.


Ultrastructural pathology of periperal nervous system in early diabetes.


Neurological findings in chemical diabetes.


Neurological changes in early diabetes.

Neurological changes in early diabetes.


Clinical features of peripheral neuropathy associated with hypoglycemia.


Malakoplakia of the skin: report of a case.


Lymphography and patients' reactions.

Lymphography and patients' reactions.


Initial psychological research related to the Occupational Safety and Health Act of 1970.


Anesthetic effects on cerebral metabolism.


Electroretinogram and afferent visual transmission in the epileptic baboon Papio papio. Effects of drugs influencing monoaminergic systems.


Treatment of infantile spasms and Lennox-Gastaut syndrome with clonazepam (Rivotril).


Preparation and purification of a structural sialofucoglycoprotein from the bovine lens capsule.


Lens polyol dehydrogenase.

Lens polyol dehydrogenase.


Morphology and biological properties of transplantable tumours induced by polyoma virus.


Relationships among pollution indicator bacteria isolated from raw water and distribution systems by the presence-absence (P-A) test.


Effect of anaerobiosis on respiratory rate, cytochrome oxidase activity and mitochondrial structures in coleoptiles of rice (Oryza sativa L.).


Studies on contract inhibition of growth in the mouse fibroblast, 3T3. I. Changes in cell size and composition during 'unrestricted' growth.


Studies on contact inhibition of growth in the mouse fibroblast, 3T3. II. Effects of amino acid deprivation and serum on growth rate.


The future of medical practice.

The future of medical practice.


Relapsing peripheral neuropathy in association with renal carcinoma.


Genetic origin of RD114 and other RNA tumour viruses assayed by molecular hybridization.


Purification of oestradiol receptors by affinity chromatography.


Extensive homology of RD114 virus DNA with RNA of feline cell origin.


Partial characterization of RD114 virus by DNA-RNA hybridization studies.


Measurement of RD114 virus nucleotide sequences in feline cellular DNA.


A practitioner's experiences with adenoviral infection in Arabian foals.


Intensification of hypertriglyceridemia by either alcohol or carbohydrate.


Cyclic AMP in digestive physiology.

Cyclic AMP in digestive physiology.


Absorption of fortification iron in bread.


Evaluation of live-virus vaccine against avian encephalomyelitis in turkey breeder hens.


Ultrastructural comparison of morphogenesis and fate of Marek's disease and infectious laryngotracheitis viruses in chicken kidney cells.


A polymer of N-acetylglucosamine 1-phosphate in the wall of Staphylococcus lactis 2102. 1. Walls of Staphylococcus lactis 2102 contain about 40% of a phosphorylated polysaccharide, which was isolated by extraction with cold trichloroacetic acid, with dilute NaOH, and also by digestion with a Flavobacterium peptidase. 2. The purified polymer contained equimolar proportions of N-acetylglucosamine and phosphate as its sole constituents and was readily hydrolysed under gentle acidic conditions to N-acetylglucosamine 6-phosphate. 3. Studies on the intact polymer showed that it is linear and that adjacent acetamido sugar units are joined by phosphodiester bonds between their 1- and 6-positions, the glycosidic linkages having the alpha-configuration. This polymer is thus the simplest of the known microbial wall polymers possessing sugar 1-phosphate linkages. 4. Alkali degradation of the extracted polymer proceeds predominantly in a stepwise manner from the reducing end, but evidence was obtained for the direct hydrolysis of some of the inter-unit phosphodiester groups.


Isolation and characterization of C1q, a subcomponent of the first component of complement, from human and rabbit sera. 1. C1q, a subcomponent of the first component of complement, has been isolated, in a haemolytically active and soluble form, by ion-exchange chromatography and gel filtration, from human and rabbit sera. Yields ranged from 10 to 25mg/litre of serum and the activity of final preparations was consistently in the range 5x10(3)-15x10(3) C1qH(50) units/mg. 2. The molecular weights of human and rabbit subcomponent C1q were 409600 and 417600, as determined by sedimentation equilibrium studies. 3. Subcomponent C1q from both species was shown to be composed of non-covalently linked subunits of approximately 57000 molecular weight as determined by gel-filtration or sedimentation equilibrium studies in 5.3m-guanidinium chloride. Reduction or oxidation of human and rabbit subcomponent C1q yielded three chains each having a molecular weight of approximately 23000 and which differed slightly in amino acid composition but markedly in carbohydrate content. The oxidized chains were separated, on a preparative scale, by ion-exchange chromatography in 8m-urea on DEAE-cellulose. 4. Both human and rabbit subcomponent C1q contained hydroxyproline, hydroxylysine, a high percentage of glycine and approximately 8% carbohydrate. Glutamic acid and aspartic acid were the free N-terminal amino acids of human subcomponent C1q whereas only serine was found in rabbit subcomponent C1q. 5. Collagenase digestion of human or rabbit subcomponent C1q caused a rapid loss of haemolytic activity which correlated with the breakdown of collagenous regions in the molecule.


Anthranilate synthase-anthranilate 5-phosphoribosyl 1-pyrophosphate phosphoribosyltransferase from Aerobacter aerogenes. 1. Anthranilate synthase and phosphoribosyltransferase from Aerobacter aerogenes purify simultaneously and sediment together on sucrose gradients, showing that they occur as an enzyme aggregate. Both activities of the intact aggregate are subject to inhibition by tryptophan. 2. By using appropriate auxotrophic mutants it was shown that an intact active enzyme aggregate is formed when the components come from separate mutant strains. An intact active aggregate can also be formed when one component is from Escherichia coli and the other from A. aerogenes. 3. Phosphoribosyltransferase of A. aerogenes is active when not in an aggregate with anthranilate synthase, but is not subject to tryptophan inhibition, indicating that the inhibitor site is on the anthranilate synthase component. 4. Anthranilate synthase can be active and sensitive to tryptophan inhibition when complexed with an inactive phosphoribosyltransferase. 5. Kinetic studies on the anthranilate synthase activity show that tryptophan is a competitive inhibitor with respect to chorismate and a non-competitive inhibitor with respect to either glutamine or NH(4) (+) ions. This is consistent with a sequential mechanism of the ordered type in which chorismate is the first reactant.


The amino acid sequences of cytochromes c-551 from three species of Pseudomonas. The amino acid sequences of the cytochromes c-551 from three species of Pseudomonas have been determined. Each resembles the protein from Pseudomonas strain P6009 (now known to be Pseudomonas aeruginosa, not Pseudomonas fluorescens) in containing 82 amino acids in a single peptide chain, with a haem group covalently attached to cysteine residues 12 and 15. In all four sequences 43 residues are identical. Although by bacteriological criteria the organisms are closely related, the differences between pairs of sequences range from 22% to 39%. These values should be compared with the differences in the sequence of mitochondrial cytochrome c between mammals and amphibians (about 18%) or between mammals and insects (about 33%). Detailed evidence for the amino acid sequences of the proteins has been deposited as Supplementary Publication SUP 50015 at the National Lending Library for Science and Technology, Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1973), 131, 5.


A membrane-bound activity catalysing phosphatidylinositol breakdown to 1,2-diacylglycerol, D-myoinositol 1:2-cyclic phosphate an D-myoinositol 1-phosphate. Properties and subcellular distribution in rat cerebral cortex. 1. Breakdown of phosphatidylinositol was studied in homogenates and subcellular fractions of rat cerebral cortex by using both membrane-bound and externally added [(32)P]phosphatidylinositol as substrate. 2. In the presence of deoxycholate breakdown followed first-order kinetics at low substrate concentrations ([unk]1mm) and zero-order kinetics at higher concentrations (6-9mm). 3. Maximum breakdown by cerebral-cortex homogenates was approximately 0.5mumol/h per mg of protein and occurred at pH7.0 in the presence of 8mm-phosphatidylinositol, 2mm-CaCl(2) and 2mg of deoxycholate/ml. Activity was abolished by 1mm-ethanedioxybis(ethylamine)tetra-acetate. 4. The products of phosphatidylinositol breakdown were 1,2-diacylglycerol and a mixture of d-myoinositol 1:2-cyclic phosphate (55%) and d-myoinositol 1-phosphate (45%). The two phosphate esters appeared to be produced together and in constant proportions. 5. Some 51% of the activity was particle-bound, with the highest activities in small nerve endings, microsomal material and two synaptic membrane fractions (fractions Mic(20), Mic(100), M(1) 1.0 and M(1) 0.9 respectively), all of which were also rich in acetylcholinesterase and which have been shown to be rich in other surface-membrane enzymes. Much of the particle-bound activity therefore appears to be present in cerebral-cortex plasma membranes. 6. The results are discussed in relation to previously described soluble activities that catalyse the same reaction, and to a possible role of the membrane-bound enzyme in enhanced phosphatidylinositol turnover in externally stimulated cells.


The nature of polydisperse ribonucleic acid in plants. The aggregation of ribosomal RNA species during chromatography on methylated albumin on kieselguhr was decreased from 50 to 15% by the lower salt concentrations made possible by the use of higher pH values. The polydisperse RNA was resolved into two fractions. About 50% was eluted with the rRNA whereas the remainder was bound to the column, and was recovered only by solubilization of the methylated albumin. Both fractions of polydisperse RNA were similar in size range, but the bound fraction was considerably richer in AMP. No D-RNA (DNA-like RNA) peak was resolved under these conditions of column fractionation. However, the properties of the bound RNA were consistent with it containing both D-RNA and TB-RNA (tenaciously bound RNA). The relationship between these two fractions of AMP-rich RNA was considered. The bound RNA and ribosomal RNA responded differently to various treatments. The salt concentration required to elute ribosomal RNA was halved by increasing the pH of the fractionation, but the amount of bound RNA was in fact increased. Denaturation by hot urea decreased the binding of ribosomal RNA to the methylated albumin, but did not facilitate elution of bound RNA. The high affinity between the AMP-rich polydisperse RNA and the methylated albumin does not therefore appear to arise for the secondary structure conferred by the high AMP content.


Iron metabolism in the veal calf. 2. Iron requirements and the effect of copper supplementation.


Nucleotide sequence analysis with polynucleotide kinase and nucleotide "mapping" methods. 5'-Terminal sequences of deoxyribonucleic acid from bacteriophages lambda and 424. The polynucleotide kinase reaction was used in analyses of complex mixtures of oligodeoxynucleotides which were fractionated by various two-dimensional nucleotide ;mapping' procedures. Parallel ionophoretic analyses on DEAE-cellulose paper, pH2, and AE-cellulose paper, pH3.5, of venom phosphodiesterase partial digests of 5'-terminally labelled oligonucleotides enabled the sequence of the nucleotides to be deduced uniquely. A ;diagonal ionophoresis' method has been used with mixtures of nucleotides. Application of these methods to 5'-terminally labelled DNA from bacteriophage lambda gave the terminal sequences pA-G-G-T-C-G and pG-G-G-C-G. Identical 5'-terminal sequences were found with DNA from bacteriophage 424.


The effects of supplements varying in carotene and calcium content on the physical, biochemical and skeletal status of preschool children.


Site of latent herpes.

Site of latent herpes.


A sequence of seventy-three nucleotides from the coliphage R17 genome. 1. A sequence of 73 nucleotides of the RNA genome from coliphage R17 was determined. It can be read through in only one translational frame. The fragment is not part of the coatprotein cistron (Min Jou et al., 1972), nor does it come from the untranslated sequences described previously (Steitz, 1969; Nichols, 1970; Cory et al., 1970; de Wachter et al., 1971; Contreras et al., 1971; Cory et al., 1972). It contains two sequences of 23 and 24 nucleotides, 22 of which are identical. This kind of reiteration is the first one found in bacteriophage nucleic acid. 2. Improved conditions were found and tested for blocking oligonucleotides with carbodi-imide and cleaving by ribonuclease A at cytidylate residues. 3. A synthetic medium is described which allows labelling in vivo with (32)P to give specific radioactivities higher than those obtained in the procedures used previously.


Infantile herpes zoster after intrauterine exposure to varicella.


Beclomethasone dipropionate steriod aerosol in treatment of perennial allergic asthma in children. Thirty-one chronic perennial asthmatics aged from 2(1/2) to 16 years were treated with beclomethasone dipropionate pressurized aerosols for up to 20 months. Of these, 16 patients dependent on oral corticosteroid or corticotrophin for up to 11 years were successfully transferred to this treatment, with one exception. Steroid withdrawal symptoms were slight. Loss of weight, disappearance of Cushingoid features, and resumption of growth indicated lack of systemic side effects. Fifteen others inadequately controlled on bronchodilators or disodium cromoglycate, were also effectively treated, and no clinical evidence of adrenal suppression was noted.


Inhibitory interaction between X and Y units in the cat lateral geniculate nucleus.


A cholinergic inhibitory system in the frog optic tectum: its role in visual electrical responses and feeding behavior.


Synaptogenesis and the development of neurotransmitter enzymes in organotypic cultures of chick spinal cord.


Characterization of central angiotensin II receptors involved in the elicitation of drinking in the rat.


Tetanus toxin blocks the efferent endings in the cochlea.


d-Tubocurarine does not antagonize the inhibitory effects of GABA at the crustacean neuromuscular junction.


Antagonism of neuronal excitation by 1-hydroxy-3-aminopyrrolidone-2.


Comparison of effects of noradrenaline and histamine with cyclic AMP on brain stem neurones.


Effects of intracerebral injections of 5,6-dihydroxytryptamine on central monoamine neurons: evidence for selective degeneration of central 5-hydroxytryptamine neurons.


Effect of two ACTH-analogs on noradrenaline metabolism in rat brain.


Cytosol-modulated transport of messenger RNA from isolated nuclei.


Anemia virus as a distinct component of the murine leukemia-sarcoma complex of viruses.


A high susceptibility of Fanconi's anemia to chromosome breakage by DNA cross-linking agents.


Cholesterol metabolism in rats bearing Morris hepatoma 7777.


Modification of hexosaminidase isozymes in rat hepatoma.


Glucagon and prostaglandin E1 stimulation of cyclic adenosine 3', 5'-monophosphate levels and adenylate cyclase activity in benign hyperplastic nodules and malignant hepatomas of ethionine-treated rats.


Development of an analytical system based around a miniature fast analyzer.


Viral investigations in ulcerative colitis and regional enteritis.


Herpesvirus saimiri: experimental infection of squirrel monkeys (Saimir sciureus).


Tumorigenicity assays in nonhuman primates treated with antithymocyte globulin.


Inhibition of human rhabdomyosarcoma-cell growth in agar by dibutyryl cyclic AMP.


Effects of the antifertility drug enovid in five strains of mice, with particular regard to carcinogenesis. The antifertility drug, Enovid, was tested for possible carcinogenicity in female mice of 5 specially selected strains: BALB/c, C3H, C3HfB, A, and C57BI.  Enovid was chosen for testing since it is one of the most widely used oral contraceptives.  The 5 strains of mice provided maximum genetic variation in the test animals.  The drug was fed at 3 dose levels: 5 mcg/gm, 10 mcg/gm and 20 mcg/gm of food.  The lowest dose did not prevent reproduction.  The 10 mcg dose prevented some females from reproducing.  The 20 mcg dose prevented all females from reproducing.  The strains of mice differed in their response to Enovid.  Weight gain was reduced in all strains.  Effect on life-span varied, partly because of the tumors.  Cervical and vaginal lesions showed invasion of the epithelium into the stroma but was limited, with few exceptions to the BALB/c females.  In the BALB/c strain these lesions occurred in controls as well, but showed more progression and a higher incidence with the highest dose of Enovid.  None of these lesions appeared grossly as tumors and none had extended beyond the vaginal wall or metastasized.  They were observed only on histologic sections.  Neither ovarian nor mammary gland tumors were increased in any strain.  In the C3H strain such tumors seemed to be inhibited.  In the C3HfB strain there was some inhibition of hepatomas and in the BALB/c strain some inhibition of adrenocortical adenoma.  Chromophobe adenomas of the hypophysis were significantly increased in old C57BI females treated with the highest dose of Enovid.  Offspring of Enovid-treated females showed no abnormalities.  Enovid increased the occurrence and may have advanced the progression of epithelial lesions of the cervix and vagina of old BALB/c females.  A study of the lesions in untreated females of this strain might help the understanding of carcinoma in situ in women and possibly the appearance of adeno-carcinoma of the vagina of young women whose mothers had been treated with stilbestrol during the first trimester to maintain pregnancy.   Other neoplasms in this strain were not increased by the Enovid therapy.  In the C3H strain mammary tumors were reduced by the Enovid and those that did occur were found later than in controls.  Results from experimental animals should be applied to humans with care.  Such results are of greatest value in directing attention to certain areas for investigation.


C-type virus particles in placentas and fetal tissues of Rhesus monkeys.


Blastogenic transformation assay for detection of immunologic reactivity to avian oncornaviruses.


Rejection of polyoma virus-induced neoplasms in mice inoculated with complement and antiserum.


Relationship between nuclear pockets in bovine peripheral blood lymphocytes and C-type virus particles in cultures of these cells.


Antibodies associated with Epstein-Barr virus in Burkitt's lymphoma during injections of BCG or irradiated autochthonous tumor cells.


Amino acid distribution in the nervous system of the crab, Carcinus maenas (L.).


Lymphosarcomas in two gibbons (Hylobates lar) with associated C-type virus.


Effects of acetylcholine on the incorporation of (32P)orthophosphate in vitro into the phospholipids of subsynaptosomal, membranes from guinea-pig brain.


Accumulation of adenosine 3', 5'-monophosphate in incubated slices from discrete regions of squirrel monkey cerebral cortex: effect of norepinephrine, serotonin and adenosine.


Metastasising chondroid syringoma.

Metastasising chondroid syringoma.


Enzymatic regulation of adenosine 3',5'-monophosphate (cyclic AMP) in the freezing epileptogenic lesion of rat brain and in homologous contralateral cortex.


Histologically benign mixed parotid tumour with hepatic metastasis.


Auto-antibodies in acute viral hepatitis, yellow fever, and hepatocellular carcinoma: clinical and experimental findings.


Pigmented progonoma in a dermoid cyst of the ovary.


The effect of isoprenaline on cyclic AMP concentrations in skeletal muscle.


An inhibition of post-ganglionic motor transmission in the mammalian vas deferens by D-lysergic acid diethylamide. 1. Under certain conditions D-lysergic acid diethylamide (LSD), 10(-9)-10(-6) g/ml., exerted an immediate, prolonged and slowly reversible inhibitory effect upon the post-ganglionic motor transmission in desheathed guinea-pig vas deferens preparations.2. The most critical factor influencing this action of LSD appeared to be the train length. With short trains of less than 4 or 5 pulses the twitch inhibition produced by LSD was often total. With longer trains (5-20 pulses), the degree of inhibition declined with increase in train length. These results suggest the existence of two components in the motor response to post-ganglionic stimulation, distinguished by their susceptibility to LSD.3. The inhibition of the LSD-susceptible component was related to the dose of LSD in the range 10(-9)-10(-6) g/ml., reaching a maximum at 0.5-1 x 10(-6) g/ml. The response remnants elicited by trains of more than 5 pulses under these conditions could not be reduced further by a ten- to twenty-fold increase in LSD concentration to 10(-5) g/ml. and were in fact slightly potentiated.4. The inhibition of post-ganglionic motor transmission by LSD was not explicable on the basis of an alpha-adrenoceptor blockade because it was not associated with any reduction in motor responses to noradrenaline.5. The use of propranolol excluded mediation of the LSD-inhibition by beta-adrenoceptors.6. The LSD effect was not due to a non-specific smooth muscle depression because it was not associated with any reduction in motor responses to acetylcholine, ATP or bradykinin.7. The inhibitory effect of LSD on post-ganglionic transmission resembled that of noradrenaline in that it was antagonized by phentolamine; another alpha-adrenoceptor blocking agent, phenoxybenzamine, was less effective than phentolamine in this respect.8. The LSD-inhibition was obtained in preparations taken from reserpinized guinea-pigs.9. The inhibition of motor transmission in the vas deferens by LSD was confirmed in rats, Meriones shawii and rabbits.10. The inhibition of post-ganglionic transmission by LSD was unrelated to its ability to antagonize 5-hydroxytryptamine (5-HT), to which the longitudinal muscle of the guinea-pig vas deferens is insensitive. The more potent 5-HT antagonists, methysergide and BOL 148 were either virtually inactive or considerably weaker than LSD.


Pancreatic acinar cells: ionic dependence of the membrane potential and acetycholine-induced depolarization. 1. Intracellular recordings of membrane potentials have been made in vitro from the exocrine acinar cells of the mouse pancreas using glass micro-electrodes.2. The mean membrane potential of the acinar cells during superfusion with Krebs-Henseleit solution was -39.2 mV. Increasing [K](o) tenfold decreased the membrane potential by 28 mV when [K](o) was above 10 mM. This depolarization was not affected by atropine (1.4 x 10(-6)M). Strophanthin-G (10(-3)M) slowly depolarized the cells at about 10 mV hr(-1).3. Brief exposure to acetylcholine (ACh), 5.5 x 10(-5)M, or pancreozymin resulted in a short lasting depolarization of the acinar cells. Atropine (1.4 x 10(-6)M) blocked the depolarizing action of ACh but not that of pancreozymin. Adrenaline (5.5 x 10(-5)M) or cyclic AMP (10(-3)-10(-4)M) did not influence the membrane potential.4. The amplitude of the ACh-induced depolarization was not dependent on the presence of CO(2)/HCO(3) in the bathing fluid, but it was closely dependent on the extracellular Na concentration. However, ACh was still able to evoke a small depolarization even after prolonged exposure of the tissue to a Na-free solution.5. During exposure of the tissue to a Ca-free solution the resting membrane potential was decreased and the ACh-induced depolarization was significantly reduced. Some substances which are known in other tissues to inhibit membrane Ca(2+) currents, i.e. La(3+), D-600 and tetracaine, were able to reduce, but never abolish, the ACh-induced depolarization.6. These results suggest that the effect of ACh on the pancreatic acinar cell is to increase the permeability of the membrane to commonly occurring ions with a consequent Na-influx and a small Ca-influx.


The effect of procaine hydrochloride and insulin on the cyclic AMP mediated responses in rat adipose tissue.


Effects of membrane depolarization on light scattering by cerebral cortical slices. 1. A system is described for simultaneously measuring the respiration and the reflectance of a tissue slice and is applied to a study of guinea-pig cerebral cortical slices.2. Reducing bathing medium osmolarity led to a reversible decrease in reflectance of these slices (as well as slices from liver and kidney cortex). In half isotonic solutions reflectance was reduced by 31%.3. Anoxia led to a decreased reflectance which was eliminated if all the Cl was substituted by the larger glucuronate anion.4. It is concluded that slice reflectance is lowered when cellular volumes are increased by water or isotonic solution influx.5. Membrane depolarization effected by ouabain, high (60 mM) K bathing medium, veratridine or repeated electrical pulses led to rapid decreases in reflectance of 25, 27, 31 and 7.5% respectively. Turning off the electrical pulses caused reflectance to return to control values. Reversibility of the chemical effectors was not tested.6. Substitution of Cl by glucuronate abolished the reflectance changes, although it did not inhibit the increased respiration induced by the depolarizing stimuli.7. Tetrodotoxin abolished both the respiratory and reflectance effects of veratridine and electrical pulses but had no effect upon those of high K or ouabain.8. The decrease in reflectance began about 1 sec after initiation of the pulses and was half maximal by 8 sec.9. Titrating reflectance against [K] showed that an increase of 5 mM-K led to a 4% decrease in reflectance and that reflectance became minimal between 60 and 80 mM-K(+).10. It is concluded that membrane depolarization in excitable cells of the cerebral cortex (and also, possibly, in the glia) causes rapid increases in cell volume due to influx of isotonic solution.11. The results indicate, more specifically, that changes in intercellular K concentrations of size and duration thought to occur following nervous activity in the C.N.S. cause cell volume changes large enough to drastically reduce the intercellular volumes and so, transiently, increase extracellular molecular and ionic concentrations. Increases of extracellular [K] and [Ca] have significant effects upon synaptic transmission and upon spontaneous nervous activity. It is suggested that nervous activity in one cell (or portion of it) might, in this way, strongly influence function in neighbouring elements.


The rabbit rectococcygeus, a smooth muscle preparation with an atropine-susceptible cholinergic motor transmission.


In vitro production of apolipoproteins in rat liver slices.


Adenoid cystic carcinoma of the trachea. Response to colbalt-60.


Carcinoembryonic antigen in patients with carcinoma of the lung.


Management of the acute burn patient--1973.


The dependence of thoracic surgery on radiology.


Virus-induced cholesterol crystals.

Virus-induced cholesterol crystals. One of the crystal types induced in cell cultures by a new feline herpesvirus was identified as cholesterol by crystal structure, polarized light microscopy, and mass spectroscopy.


Neurologic findings in retroperitoneal mass lesions.


Pseudomonas endocarditis.

Pseudomonas endocarditis.


Pancreatic islet cell carcinoma. I. Clinical features of 52 patients.


Pancreatic islet cell carcinoma. II. Results of therapy with streptozotocin in 52 patients.


Segmental renal-vein renin sampling for segmental renal infarction. Studies in a hypertensive patient.


Optic neuropathy of Graves disease, hyperthyroidism, and ocular myasthenia gravis.


Demonstration of a glucocorticoid hormone-receptor complex in the cytoplasm of a hormone-responsive tumour. Specific substances binding [(3)H]-triamcinolone acetonide have been demonstrated in the cytoplasmic fraction of the R3230AC mammary carcinoma using sucrose gradient centrifugation. These receptors, which exhibit sedimentation coefficients of 8-9 Svedberg units, are relatively specific for glucocorticoid ligands and possess a high affinity for triamcinolone acetonide (K(d)∼7 × 10(-8) mol/1).


The induction of tumours in the guinea-pig with methylcholanthrene and diethylnitrosamine and their propagation in vivo and in vitro. Tumour induction with diethylnitrosamine (DEN) and methylcholanthrene (MCA) has been studied in 3 strains of guinea-pig. A DEN concentration of 80 μg/ml drinking water daily proved too toxic but reasonable survival was obtained with 20 μg/ml 3 times per week in Hartley guinea-pigs and a local inbred strain. Heston Strain 13 guinea-pigs were particularly susceptible to the toxic effects of the diethylnitrosamine. In all3strains, 100% of the animals which survived the early toxic effects subsequently developed hepatomata, the mean time being 15 months. Methylcholanthrene was less toxic but more erratic as a carcinogen, the incidence of tumours in Hartley guinea-pigs varying from 18 to 100% in different experiments, the mean time of tumour development being 10 months.Three transplantable hepatomata and 3 transplantable sarcomata have been developed. The hepatomata are all predominantly hepatocellular carcinomata and the sarcomata comprise two liposarcomata and a fibrosarcoma. Successful shortterm primary cultures of hepatomata, sarcomata and of normal liver tissues have been accomplished. Established cell lines in tissue culture have been developed from one cholangiocarcinoma from an outbred guinea-pig and one transplanted hepatocellular carcinoma from an inbred guinea-pig.


Increased carcinogenic action of dimethylnitrosamine after prior administration of carbon tetrachloride. Rats were given a single dose of dimethylnitrosamine (DMN, 20 mg/kg body weight) alone or 42 or 60 hours after a non-lethal hepatotoxic dose of carbon tetrachloride (CC1(4)) and killed 12 months later. DMN alone produced no tumours in the kidney and a few in the liver, but when given 42 hours after CC1(4), tumours formed in the kidneys and the number in the liver was increased. When given after 60 hours, the incidence of kidney tumours was less but that of liver tumours was further increased. A larger dose of DMN (40 mg/kg) was tolerated 42 hours after CC1(4) and enhanced the number of kidney and liver tumours, the latter apparently due to an increased proportion of cholangiomata. Numerous small focal proliferations of atypical liver cells and of bile duct epithelium were observed after treatment with DMN. The incidence of these lesions in the different experimental treatments varied in a similar manner to the liver tumours.


Cystathionine excess in children with hepatic cancer.


Inhibition of malignant cell invasion in vitro by a proteinase inhibitor. The inhibitory effect of the protease inhibitor aprotinin (Trasylol) on the invasion of mouse kidney explants by polyoma virus transformed BHK21 cells was investigated using a mixed cell/organ culture technique. The extent of invasion was monitored by following the changes in LDH isoenzyme pattern in the explants and by histological assessment. The kidney explants containing aprotinin were found to maintain a normal kidney LDH pattern and to suffer considerably less invasion than the explants not containing the drug. These results support the idea that proteolytic enzymes are associated with invasion and that inhibitors of protease activity could possibly be useful in the management of clinical cancer.


Age- and sex-associated diethylnitrosamine dealkylation activity of the mouse liver and hepatocarcinogenesis.


Structural and functional changes in Novikoff hepatoma mitochondria.


Viral disease of the labyrinth. II. An experimental model using mouse cytomegalovirus.


Competitive RNA-DNA hybridization of nuclear and microsomal RNA during diethylnitrosamine hepatocarcinogenesis.


Carcinogenesis by urethan via mother's milk and its enhancement of transplacental carcinogenesis in mice.


The metabolism and binding of testosterone in androgen-dependent and autonomous transplantable mouse mammary tumors.


Specific antigens in human alveolar cell carcinoma.


Fine structure of primary liver tumors and tumor-bearing livers in man.


Further observations on the effects of trypsin on the volume and functions of mitochondria isolated from normal liver and AH-130 Yoshida ascites hepatoma.


Modification of rabbit adrenal steroid biosynthesis by prolonged ACTH administration.


Adrenocortical control of catecholamine metabolism in the dog adrenal medulla: relationship to protein synthesis.


Reversible inhibition of ACTH-induced corticosteroid release by cycloheximide: evidence for an unidentified cellular messenger.


Dynamics of insulin release by perfused rat pancreases: effects of hypophysectomy, growth hormone, adrenocorticotropic hormone, and hydrocortisone.


Thyrotropin releasing hormone (TRH): neurotransmitter regulation of secretion by mouse hypothalamic tissue in vitro.


Regulation of steroidogenesis by ACTH in a superfusion system for isolated adrenal cells.


Indomethacin, lipolysis, and cyclic AMP accumulation in white fat cells.


Nuclear receptor estrogen complex: accumulation, retention and localization in the hypothalamus and pituitary.


Vitamin D and intestinal transport of calcium: effects of prednisolone.


Effects of estrogens on renin substrate and uterine weights in rats.


The gonadotropin-primed rat: a model for testing agents that influence steroid biosynthesis.


The chest roentgenogram in babies of 1000 grams or less.


Desquamative interstitial pneumonia: progression to the end-stage lung and the unusual complication of alveolar cell carcinoma: case report.


The activation of coagulation by extracts of mucus: a possible pathway of intravascular coagulation accompanying adenocarcinomas.


The actions of penicillin and other antibiotics on bacterial cell wall synthesis.


Lateral inhibition and cognitive masking: a neuropsychological theory of attention.


Arteriographic demonstration of two islet-cell tumors in a patient with Zollinger-Ellison syndrome.


Urinary excretion of cyclic adenosine monophosphate in the detection and diagnosis of primary hyperparathyroidism.


Bilateral carcinoma of the breast.

Bilateral carcinoma of the breast.


Genetic regulatory systems in Neurospora.


The genetics of transmissible plasmids.

The genetics of transmissible plasmids.


The operon revisited.

The operon revisited.


Confirmation of the 1-20 amino acid sequence of human adrenocorticotrophin. The tryptic fragments of natural human adrenocorticotrophin, were separated by countercurrent distribution and a correction in positions 25, 26, 27 and 30 was made by Riniker et al. (1972) in a study of the fragment containing residues 22-39. We have purified the remaining tryptic fragments, namely residues 1-8, 9-15, 16-21 and 17-21, by using ion-exchange chromatography on CM-cellulose and have carried out sequence determination by using the subtractive Edman degradation procedure and digestion with aminopeptidase M and carboxypeptidase B. These results have confirmed the proposed sequence for human adrenocorticotrophin in regions 6-7, 10-14 and 17-20, which had previously been arrived at only by analogy with the invariant sequence found in the three other mammalian adrenocorticotrophin species that had been investigated.


The effects of glucagon and insulin on adenosine 3':5'-cyclic monophosphate concentrations in an organ culture of mature rat liver. 1. A modified radioimmunoassay for cyclic AMP was developed from the method of Steiner et al. (1969). Cyclic [(3)H]AMP was used as the radioactive tracer. Free and antibody-bound nucleotides were separated by adsorption of protein to Millipore filters. The assay was used to measure amounts of cyclic AMP down to 0.1pmol in 50mul. 2. The effect of glucagon on cyclic AMP content in pieces of mature rat liver maintained for 6 days in organ culture was studied. 3. Cyclic AMP content in the tissue reached a maximum in 5-15min and then decreased. This may have been partly due to an inhibitor of glucagon action formed in the tissue. Small amounts of cyclic AMP were released into the incubation medium. 4. The maximal increase in cyclic AMP content produced by glucagon decreased over 6 days in culture. However, liver pieces cultured for 2 and 6 days were more sensitive to low concentrations of glucagon than were fresh liver pieces. Glucagon concentrations for half-maximal effects were approx. 1mum and 0.05mum for fresh liver and 2-day cultured liver respectively. 5. Insulin (3.5mum) lowered the cyclic AMP content by 30% in the presence of a submaximal glucagon concentration in liver cultured for 2 days. No effect of insulin was demonstrated on fresh liver pieces. 6. Insulin and glucagon were rapidly destroyed by fresh liver pieces.


D-3-hydroxybutyrate dehydrogenase from Rhodopseudomonas spheroides. Kinetic mechanism from steady-state kinetics of the reaction catalysed by the enzyme in solution and covalently attached to diethylaminoethylcellulose. 1. The reversible NAD(+)-linked oxidation of d-3-hydroxybutyrate to acetoacetate in 0.1m-sodium pyrophosphate buffer, pH8.5, at 25.0 degrees C, catalysed by d-3-hydroxybutyrate dehydrogenase (d-3-hydroxybutyrate-NAD(+) oxidoreductase, EC 1.1.1.30), was studied by initial-velocity, dead-end inhibition and product-inhibition analysis. 2. The reactions were carried out on (a) the soluble enzyme from Rhodopseudomonas spheroides and (b) an insoluble derivative of this enzyme prepared by its covalent attachment to DEAE-cellulose by using 2-amino-4,6-dichloro-s-triazine as coupling agent. 3. The insolubilized enzyme preparation contained 5mg of protein/g wet wt. of total material, and when freshly prepared its specific activity was 1.2mumol/min per mg of protein, which is 67% of that of the soluble dialysed enzyme. 4. The reactions catalysed by both the enzyme in solution and the insolubilized enzyme were shown to follow sequential pathways in which the nicotinamide nucleotides bind obligatorily first to the enzyme. Evidence is presented for kinetically significant ternary complexes and that the rate-limiting step(s) of both catalyses probably involves isomerization of the enzyme-nicotinamide nucleotide complexes and/or dissociation of the nicotinamide nucleotides from the enzyme. Both catalyses therefore are probably best described as ordered Bi Bi mechanisms, possibly with multiple enzyme-nicotinamide nucleotide complexes. 5. The kinetic parameters and the calculable rate constants for the catalysis by the soluble enzyme are similar to the corresponding parameters and rate constants for the catalysis by the insolubilized enzyme.


D-3-hydroxybutyrate dehydrogenase from Rhodopseudomonas spheroides. Kinetics of radioisotope redistribution at chemical equilibrium catalysed by the enzyme in solutions. 1. The reversible NAD(+)-linked oxidation of d-3-hydroxybutyrate to acetoacetate in 0.1m-sodium pyrophosphate buffer, pH8.5, at 25.0 degrees C, catalysed by d-3-hydroxybutyrate dehydrogenase (d-3-hydroxybutyrate-NAD(+) oxidoreductase, EC 1.1.1.30), was studied kinetically at chemical equilibrium by monitoring radioisotope redistribution with sodium dl-hydroxy[3-(14)C]butyrate and [4-(3)H]NAD(+)(labelled in the nicotinamide ring). 2. When all substrates are maintained at concentrations approaching saturation (approx. 3-50 times the K(m) values) the first-order rate constant for the enzyme-catalysed interconversion of NAD(+) and NADH is much smaller than that for the enzyme-catalysed interconversion of d-3-hydroxybutyrate and acetoacetate. 3. The rate of interconversion of NAD(+) and NADH increases initially with increasing concentrations of d-3-hydroxybutyrate and acetoacetate (ratio of concentrations maintained constant), passes through a maximum and approaches closely to zero at saturating concentrations of the latter substrates. 4. The rates of interconversion of NAD(+) and NADH and of d-3-hydroxybutyrate and acetoacetate increase with increasing concentration of NAD(+) (up to 66 times its K(m) value) and NADH (up to 180 times its K(m) value) (ratio of the concentrations of the nicotinamide nucleotides maintained constant). 5. These findings support the description of this catalysis as an ordered Bi Bi mechanism with no detectable alternative pathway, in which the interconversion of the central ternary complexes is not rate-limiting, and provide no evidence for the formation of dead-end complexes. 6. The solubility of 2,4-dinitrophenylhydrazine in HCl exhibits an acidity optimum, the maximum solubility at 25.0 degrees C (3.8mg/ml, 19mm) occurring at 2.29m-HCl; in solutions of this acidity acetone 2,4-dinitrophenylhydrazone is relatively insoluble (0.098mg/ml, 0.413mm).


The effect of modifying lysine-126 on the physical, catalytic and regulatory properties of bovine liver glutamate dehydrogenase. 1. The reaction of 4-iodoacetamidosalicylate with bovine liver glutamate dehydrogenase is dependent on pH. The pH-activity curve is bell-shaped and can be described by apparent pK values of 7.8+/-0.2 and 9.1+/-0.2. 2. Enzyme in which lysine-126 has been modified by 4-iodoacetamidosalicylate has unaltered sedimentation characteristics except when measured in the presence of GTP and NADH. 3. GTP binding to the inhibited enzyme is unaltered. However, GTP can no longer promote the binding of a second molecule of NADH, since this is already bound to the inhibited enzyme without GTP. 4. The equilibrium binding of ADP, GTP, NAD-sulphite and NADH (when measured at low concentrations) was largely unchanged by modification. 5. The number of binding sites for 2-oxoglutarate to the enzyme-NADH complex were decreased by 60% in an enzyme that has been inhibited by 70%.


The reaction of a histidine residue in glutamate dehydrogenase with diethyl pyrocarbonate. 1. One mol of diethyl pyrocarbonate will react with one mol of glutamate dehydrogenase polypeptide chains to form one mol of N(1)-carbethoxyhistidine. Reaction is prevented by NADH. 2. The 1:1 complex has an increased specific activity (1.4-2.0-fold). 3. The reason for the activation is discussed. The results are not consistent with NADH dissociation from the enzyme-glutamate-NADH complex being rate-limiting in the steady state measured. 4. The effects of modification on the properties of the enzyme were investigated. The effects of GTP and NAD(+) on the enzyme activity are unaltered by activation. NADH binding is unaltered and there is no apparent change in the molecular weight. However, the activated enzyme can still be further activated by ADP. K(s) for ADP is decreased fivefold.


"If a man have a strong faith".

"If a man have a strong faith".


Excitation-contraction coupling in heart. IX. Changes in the intracellular stores of calcium in failing hearts due to lack of substrate and oxygen.


Effect of cyclic 3',5'-AMP on the (Na+K)-ATPase of myocardial sarcolemma.


Evaluation of a rapid competitive protein binding assay for progesterone in pregnancy and some of its complications.


Location of heme a in cytochrome a. I. Combination of alkyl isonitriles with cytochrome a.


Kinetic studies on hydrogenase. Parahydrogen-orthohydrogen conversion and hydrogen-deuterium exchange reactions.


L-amino acid oxidase, phosphodiesterase, total protein and other properties of juvenile timber rattlesnake (C. H. horridus) venom at different stages of growth.


Hypersensitivity to different ACTH peptides.


Evolution of cytochrome C molecule.

Evolution of cytochrome C molecule.


Actions of transmitter substances on the neuromuscular junctions of vertebrates and invertebrates.


Suprailiac lymphography.

Suprailiac lymphography.


Partial reactions of D-glucose 6-phosphate-1L-myoinositiol 1-phosphate cyclase. After removal of tightly bound NAD(+) by using charcoal, a preparation of d-glucose 6-phosphate-1 l-myoinositol 1-phosphate cyclase catalysed the reduction of 5-keto-d-glucitol 6-phosphate and 5-keto-d-glucose 6-phosphate by [4-(3)H]NADH to give [5-(3)H]-glucitol 6-phosphate and [5-(3)H]glucose 6-phosphate respectively. The position of the tritium atom in the latter was shown by degradation. Both enzyme-catalysed reductions were strongly inhibited by 2-deoxy-d-glucose 6-phosphate, a powerful competitive inhibitor of inositol cyclase. The charcoal-treated enzyme preparation also converted 5-keto-d-glucose 6-phosphate into [(3)H]myoinositol 1-phosphate in the presence of [4-(3)H]NADH, but less effectively. These partial reactions of inositol cyclase are interpreted as providing strong evidence for the formation of 5-keto-d-glucose 6-phosphate as an enzyme-bound intermediate in the conversion of d-glucose 6-phosphate into 1 l-myoinositol 1-phosphate. The enzyme was partially inactivated by NaBH(4) in the presence of NAD(+). Glucose 6-phosphate did not increase the inactivation, and there was no inactivation in the absence of NAD(+). There was no evidence for Schiff base formation during the cyclization. d-Glucitol 6-phosphate (l-sorbitol 1-phosphate) was a good inhibitor of the overall reaction. It did not inactivate the enzyme. The apparent molecular weight of inositol cyclase as determined by Sephadex chromatography was 2.15x10(5).


Kinetic properties of the partially purified pyruvate dehydrogenase complex of ox brain. The properties of a purified preparation of the pyruvate dehydrogenase complex from ox brain have been compared with those of a similar preparation from ox kidney. A broad pH optimum around 7.8, similar dependence on ionic strength, and independence of the nature of the buffer anions or cations characterized preparations from both tissues. Michaelis constants for the binding of pyruvate, thiamin pyrophosphate, NAD(+) and CoA were also similar. Enzyme from both tissues was inhibited by NADH, by copper and other heavy metals, by high concentrations of tricarboxylic acid-cycle intermediates, and by preincubation with ATP. Acetyl-CoA itself did not appear to inhibit these preparations, although some commercial preparations of acetyl-CoA did contain an inhibitor. Although oxaloacetate and alpha-oxobutyrate were weak inhibitors, a number of other alpha-oxo acids including phenylpyruvate did not inhibit. The properties of the pyruvate dehydrogenase complex from brain and kidney appeared similar.


The significance of abrupt transitions in Lineweaver-Burk plots with particular reference to glutamate dehydrogenase. Negative and positive co-operativity in catalytic rate constants. 1. Lineweaver-Burk plots for glutamate dehydrogenase, glucose 6-phosphate dehydrogenase and several other enzymes show one or more abrupt transitions between apparently linear sections. These transitions correspond to abrupt increases in the apparent K(m) and V(max.) with increasing concentration of the varied substrate. 2. The generalized reciprocal initial-rate equation for a multi-site enzyme requires several restrictions to be put on it in order to generate such plots. These mathematical conditions are explored. 3. It is shown that the effective omission of a term in the denominator of the reciprocal initial-rate equation represents a minimal requirement for generation of abrupt transitions. This corresponds in physical terms to negative co-operativity followed by positive co-operativity affecting the catalytic rate constant for the reaction. 4. Previous models for glutamate dehydrogenase cannot adequately account for the results. On the other hand, the model based on both negative and positive co-operativity gives a good fit to the experimental points. 5. The conclusions are discussed in relation to current knowledge of the structure and mechanism of glutamate dehydrogenase.


Inhibition of functional vasodilatation and prostaglandin formation in rabbit adipose tissue by indomethacin and aspirin. 1. The epigastric adipose depot of rabbits has been used to examine the effect of indomethacin, aspirin and nicotinic acid on the free fatty acid release and blood flow in fat tissue.2. The prostaglandin formation which occurs in adipose tissue during lipolysis is prevented by indomethacin and aspirin. The corresponding functional vasodilatation which occurs after infusions of lipolytic substances is also abolished by these two anti-inflammatory compounds.3. This finding is consistent with the theory that prostaglandin E(2) is the mediator of functional vasodilatation in adipose tissue.4. Nicotinic acid sometimes inhibits the release of free fatty acids from adipose tissue by preventing activation of the tissue lipase. In those experiments in which this inhibition occurred, the vasodilatation was also prevented.5. This finding is consistent with the view that the prostaglandin E(2) which mediates the functional vasodilatation, originates in the triglycerides of the fat tissue.


The release of spasmogenic substances from human chopped lung tissue and its inhibition. 1. Human lung tissue, passively sensitized with reaginic antibodies, released prostaglandins E(1), E(2) and F(2alpha) in addition to histamine and slow reacting substance (SRS-A), when exposed to the appropriate antigen. No rabbit aorta contracting substance (RCS) was detected.2. Experiments with rats and guinea-pigs showed that the release of RCS is not confined to anaphylactic reactions mediated by non-reaginic antibodies but may be a feature of anaphylaxis in guinea-pigs alone.3. Human lung tissue gently agitated with a blunt nylon rod liberated an E-type prostaglandin and RCS in addition to histamine and SRS-A.4. Human isolated bronchial muscle was contracted by RCS.5. Disodium cromoglycate antagonized the release of prostaglandins during anaphylaxis but not during agitation of human lung tissue, whereas indomethacin blocked the release of prostaglandins during agitation and anaphylaxis.6. The release of an E-type prostaglandin during anaphylaxis in human lung tissue, which inhibits the further release of histamine could be another example of the regulatory role of prostaglandins in body functions.


Effects of angiotensin, catecholamines and cyclic AMP on calcium storage in aortic microsomes. 1. The binding of calcium observed in microsomal membranes derived from the intimal-medial layer of rabbit aorta was specifically increased by the magnesium salt of adenosine triphosphate (Mg-ATP). This calcium uptake was inhibited by potassium and sodium.2. Angiotensin II, both in the presence and in the absence of Mg-ATP, reduced the binding of calcium and increased the release of membrane-incorporated calcium. These effects were dose-dependent. Analogues of angiotensin II devoid of intrinsic activity, failed to alter the release of calcium.3. Dibutyryl-cyclic AMP increased the binding of calcium and reduced the rate of its release. The maximal effect was observed at the concentration of 10(-5)M.4. (-)-Noradrenaline reduced the binding of calcium; this effect was inhibited by phenoxybenzamine. Conversely, adrenaline like cyclic AMP, increased the calcium binding; the effect of adrenaline was suppressed by a beta-adrenoceptor blocking agent.5. These observations demonstrate the existence of membranes in rabbit aorta capable of storing calcium. Excitatory drugs seem to affect directly and specifically the binding and release of calcium in these membranes.


Action of botulinum toxin on transmission from sympathetic nerves to the vas deferens. Botulinum toxin (Type A) depressed or abolished transmission from postganglionic nerves to smooth muscle of isolated preparations of guinea-pig and mouse vas deferens. The time course of blockade was 2 to 6 times slower than that observed with the same concentration of the same batch of toxin on the rat diaphragm. Spontaneous excitatory junction potentials were still observed after 7 h exposure, indicating that the smooth muscle membrane was still able to respond to noradrenaline. Depression of transmission is probably due to a presynaptic action of unknown nature.


Indolealkylamine nerve terminals in cerebral ventricles: identification by electron microscopy and fluorescence histochemistry.


Corticosterone binding to hippocampus: nuclear and cytosol binding in vitro.


Inhibition and excitation of units in paraventricular nucleus after stimulation of the septum, amygdala and neurohypophysis.


Properties of corticosterone-binding macromolecules from rat brain cytosol.


Post mortem characteristics of the hepatic microsomal drug oxidising enzyme system.


The mechanism of action of aflatoxin B1 on protein synthesis: observations on malignant viral transformed and untransformed cells in culture.


A new synthesis of furanoid fatty acids: isomerisation of hydroxy-cis-enynoic acids by alkali, and on argentous silica gel.


Early reciprocal inhibition in athetosis.


Metabolism of NAD after whole-body irradiation. IV. Incorporation of nicotinamide by isolated perfused liver and by intact rats.


Pituitary peptide.

Pituitary peptide.


Characterization of murine leukaemia virus-specific DNA present in normal mouse cells.


Similar growth of Chinese hamster cells in the presence of phenethyl alcohol or dibutyryl cyclic AMP.


Fucose-containing glycopeptides from the cell surface of Chinese hamster ovary cells grown in the presence or absence of cyclic AMP.


The role of calcium in insulin secretion.


Subclinical peripheral nerve involvement in unilateral Bell's palsy.


Aerobic and anaerobic energy metabolism in compensatory renal hypertrophy.


The gonadotropin receptor of the human corpus luteum.


Influence of cadmium ions on contractile response of isolated aortas to stimulatory agents.


Coupled sodium-chloride influx across the brush border of rabbit ileum.


Sodium dependence of base-line and ADH-stimulated short-circuit current in toad bladder.


Carcinoma of the hepatic ducts: review of 11 cases.


Inherited constriction fragility of chromosome 2.


The effect of a lipid-rich diet on the properties and composition of lipoprotein particles from the Golgi apparatus of guinea-pig liver. 1. A cell fraction rich in Golgi apparatus was isolated from the livers of guinea pigs fed on a lipid-rich diet (1.6% cholesterol, 15% corn oil). 2. The Golgi cisternae and secretory vesicles contained electron-dense particles which were tentatively identified as VLD (very-low-density) and LD (low-density) lipoproteins. Particles of moderate electron density, 150-500nm in diameter, were seen associated with membranous elements of the Golgi-apparatus cell fraction. Disruption of this cell fraction permitted the release of these three species of particles, which were separated into particulate lipid, and VLD and LD lipoproteins. 3. The large particles of moderate electron density, isolated as particulate lipid, were distinct from both species of Golgi particles in their chemical composition and in possessing an immunochemically unreactive apolipoprotein(s). Morphological observations suggest that the particulate lipid arose from cytoplasmic lipid droplets which were present as contaminants of the Golgi-rich fraction. 4. The chemical and immunochemical results are consistent with the suggestion that the Golgi LD particles are precursors of the VLD particles, into which they may be transformed by the addition of both triglyceride and cholesteryl ester. The present results provide further support for the proposal that the Golgi VLD particles are precursors of the serum VLD lipoproteins in the guinea pig. 5. Hepatic Golgi VLD particles isolated from guinea pigs fed on the lipid-rich diet contained significantly higher molar amounts (relative to protein) of both cholesteryl ester and triglyceride than similar particles from animals fed on a normal diet. These results suggest that the type of Golgi VLD particle produced from the LD particle is a direct consequence of the amount and composition of the dietary lipid. 6. Hepatic Golgi LD particles isolated from guinea pigs fed on different diets were similar in chemical composition and contained approx. 50% by weight of phospholipid. We conclude that the Golgi LD particle is normally present in the Golgi-apparatus cell fraction from guinea-pig liver, and may represent the end product of lipoprotein biosynthesis in the smooth endoplasmic reticulum. 7. The serum LD lipoproteins and Golgi LD particles were quite distinct in chemical composition. However, these two lipoprotein species were immunochemically identical and exhibited a similar range of flotation rate. It appears unlikely that the Golgi LD particles are secreted as the precursors of the serum LD lipoproteins.


The amino acid sequence of cytochrome c from Allium porrum L. (leek). The amino acid sequence of leek cytochrome c was determined with 0.4mumol of protein. The sequence was deduced solely from a chymotryptic digest. The cytochrome was homologous with other plant cytochromes c of mitochondrial origin. Leek cytochrome c has an N-acetylated ;tail' as compared with mammalian cytochrome c, and two residues of epsilon-N-trimethyl-lysine. Unlike other plant cytochromes c, leek cytochrome c has glutamic acid or glutamine in position 11, leucine in position 20 and alanine in position 51. 4-Hydroxyproline partially substitutes for proline in position 79. Experimental details are given in a supplementary paper that has been deposited as Supplementary Publication SUP 50012, at the National Lending Library for Science and Technology, Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1973) 131, 5.


The amino acid sequence of cytochrome c from Spinacea oleracea L. (spinach). The amino acid sequence of spinach (Spinacea oleracea L., var. Monster Viroflay) cytochrome c was determined on 1mumol of protein. The molecule consists of 111 residues and is homologous with other mitochondrial cytochromes c. Experimental details are given in a supplementary paper that has been deposited as Supplementary Publication SUP 50013, at the National Lending Library for Science and Technology, Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1973), 131, 5.


Milk xanthine oxidase type D (dehydrogenase) and type O (oxidase). Purification, interconversion and some properties. 1. The xanthine oxidase of cow's milk, crude or purified, appears as an oxidase (type O), and can be converted almost completely into a NAD(+)-dependent dehydrogenase (type D) by treatment with dithioerythritol or dihydrolipoic acid, but only to a small extent by other thiols. 2. The D form of the enzyme is inhibited by NADH, which competes with NAD(+). 3. The kinetic constants of the two forms of the enzyme are similar to those of the corresponding forms of rat liver xanthine oxidase. 4. Milk xanthine oxidase is converted into an irreversible O form by pretreatment with chymotrypsin, papain or subtilisin, but only partially with trypsin. 5. The enzyme as purified shows a major faster band and a minor slower band on gel electrophoresis. The slower band is greatly reinforced after xanthine oxidase is converted into the irreversible O form by chymotrypsin.


The preparation and analysis of a new trinucleotide from yeast ribonucleic acid, containing two adjacent 2'-O-methylpentose residues. Quantities of the order of 10mg of three alkali-stable trinucleotides were prepared from yeast ribonucleic acid. Analyses showed that they were of the type N1m-N2m-N3p, where m signifies 2'-O-methylation of the pentose residue. One, Am-Um-Gp, is newly described.


A study of the kinetics and mechanism of yeast alcohol dehydrogenase with a variety of substrates. 1. The kinetics of oxidation of ethanol, propan-1-ol, butan-1-ol and propan-2-ol by NAD(+) and of reduction of acetaldehyde and butyraldehyde by NADH catalysed by yeast alcohol dehydrogenase were studied. 2. Results for the aldehyde-NADH reactions are consistent with a compulsory-order mechanism with the rate-limiting step being the dissociation of the product enzyme-NAD(+) complex. In contrast the results for the alcohol-NAD(+) reactions indicate that some dissociation of coenzyme from the active enzyme-NAD(+)-alcohol ternary complexes must occur and that the mechanism is not strictly compulsory-order. The rate-limiting step in ethanol oxidation is the dissociation of the product enzyme-NADH complex but with the other alcohols it is probably the catalytic interconversion of ternary complexes. 3. The rate constants describing the combination of NAD(+) and NADH with the enzyme and the dissociations of these coenzymes from binary complexes with the enzyme were measured.


Interaction between polyuridylic acid and rabbit globin messenger ribonucleic acid. Poly(U) binds to globin mRNA in 0.1m-NaCl. Studies with ribonuclease digestion of this complex suggest that there are polyadenylate-rich sequences in the mRNA containing about 30-40 adenylate residues. The sequences appear to be homogenous and of approximately the same length for both alpha- and beta-globin mRNA. They are most likely located at the 3' terminus of the molecule.


Protein kinase activity in commercially available crystalline yeast alcohol dehydrogenase. Commercially available crystalline yeast alcohol dehydrogenase contained protein kinase activity. Casein and phosvitin were readily phosphorylated, but whole calf thymus histone was not. The protein kinase activity was inhibited by KCl, was not stimulated by cyclic AMP and could be separated from the alcohol dehydrogenase activity by sucrose density centrifugation.