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Virchows Arch A Pathol Anat Histol, 1975 Jun 23, 367(1), 35 - 45 Pancreatic cholera (W.D.H.A . syndrome) . Histochemical and ultrastructural studies; Rambaud JC et al.; Results of light and electron-microscopic studies of primary pancreatic tumor and of metastasis in a new case of Pancreatic Cholera (P.C.) are reported . The primary tumor but not the metastases, contained unusual, large cystic glandular formations, lined both by pancreatic-duct- and small-intestine-like epithelia and closely connected with the endocrine proliferation . A part from a few D-cells, the endocrine tumoral cells could not be identified by histochemical stainings . Their ultrastructural pattern, with small secretory granules (diameter less than 300 nm) and numerous cytoplasmic bunches of filaments, was very similar to that of gastric and duodenal D1-cells . Normal duodenal D1-cells have been said to produce gastric inhibitory peptide, a substance structurally and biologically similar to the vasoactive intestinal peptide actually secreted by the tumor . The normal histological appearance of gastric, gallbladder, jejunal, ileal, right and left colonic mucosae is consistent with the responsibility of the tumoral secretion in the impairment of gut functions in P.C. Proc Natl Acad Sci U S A, 1975 Jun, 72(6), 2064 - 8 Involvement of nicotinamide adenine dinucleotide in the action of cholera toxin in vitro; Gill DM; NAD is a necessary cofactor for the activation of adenylate cyclase (ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1) by cholera toxin . Lysates of certain types of cell that hydrolyze their endogenous store of NAD after cell disruption respond poorly or not at all to cholera toxin . Lysates of pigeon erythrocytes, which lack enzymes that degrade NAD, provide a convenient and reproducible system for assaying the activity of cholera toxin in vitro and allow investigation of the mechanism of action of the toxin upon broken cells. J Infect Dis, 1975 Jun, 131(6), 643 - 8 Evidence for the complex nature of the ganglioside receptor for cholera toxin; King CA et al.; Choleragenoid binds more slowly and less strongly than cholera toxin to intestinal mucosal cells, and even less strongly to free ganglioside in solution . However, binding to ganglioside is greatly enhanced when the ganglioside is in the form of an insoluble complex with cerebroside . These findings suggest that both the binding and the active components of the toxin molecule may be necessary for optimal binding of the toxin to the intact cell, and that the ganglioside in the cell receptor is in a complex form . Choleragenoid only partially blocks the action of the toxin on ruptured cells . This observation indicates that, while binding to a membrane receptor is necessary for the action of the toxin on the whole cell, it is possible to activate adenyl cyclase in a perforated cell by a process apparently independent of membrane binding; however, this activation may be possible only if the toxin preparation contains the active component dissociated from choleragenoid. Ann Sclavo, 1975 May-Jun, 17(3), 435 - 40 {Importance of atmospheric conditions in the 1973 cholera epidemic in Apulia}; Marotti S et al.; Authors briefly refer on metereologic situation during epidemic of cholera in Bari (Italy), in the summer of 1973 and discuss the possible influences upon the spread of infection . They emphasize the climatic analogies during other epidemics in Puglia and quote observations about meteo influences on outbreaks in Asiatic areas. Ann Sclavo, 1975 May-Jun, 17(3), 419 - 34 {Renal complications of Asiatic cholera}; Amerio A et al.; Seventy cases of cholera were admitted to Hospital during 1973 cholera epidemic; 49 showed the symptoms of renal failure, 19 of whom with anuria . Acute renal failure is caused from hypertonic or isotonic dehydration, metabolic acidosis and potassium depletion . Clinically the pattern of a tubulo-interstitial nephritis can be found; a short oliguric or anuric phase followed by a poliuric phase lasting about 10 days . The glomerular function usually cames back to normal in 20 days time . As for the therapy, 16 of the above mentioned 19 anuric patients received a conservative treatment only; 3 patients with preexisting chronic nephropathy required peritoneal dialysis . Only one patient died and one patient with lupic nephropathy was put on chronic haemodialysis treatment . Concluding: 17 patients out of 19 completely recovered their renal function. Infect Immun, 1975 May, 11(5), 982 - 5 Inhibition of the steroidogenic effects of cholera and heat-labile Escherichia coli enterotoxins by GM1 ganglioside: evidence for a similar receptor site for the two toxins; Donta ST et al.; The effects of three different ganglioside preparations on cholera enterotoxin (CT) and heat-labile Escherichia coli enterotoxin (ECT)-induced steroidogenesis in Y1 and OS3 adrenal tumor cells in tissue culture were examined . Only with GM1 ganglioside was any inhibition of the toxins' effects noted . Concentrations of the crude ECT preparation that gave similar morphogenic and steroidogenic effects as CT were inhibited by the same amount or less of GM1 as that required to inhibit the effects of CT . The results of competition experiments also demonstrated that previous incubation of GM1 with one toxin could inhibit the ganglioside's ability to inactivate the other toxin . These findings indicate that at least for Y1 and OS3 adrenal tumor cells, GM1 may resemble or be the receptor for both CT and ECT. Am J Vet Res, 1975 May, 36(5), 611 - 4 Transmission of hog hog cholera virus by mosquitoes; Stewart WC et al.; Mosquitoes trapped during an epizootic of hog cholera (HC) in Maryland in 1969 were prepared into 40 pools which were inoculated in pigs . Hog cholera virus was confirmed in pigs inoculated with 8 of 40 pools of mosquitoes . Generally, the pigs contracting HC developed chronic infections with persistent viremia that lasted 30 or more days . Two pigs seemed healthy when euthatized 62 and 80 days after inoculation, yet viremia of high titer was detected in each . Experimental studies were performed with 2 laboratory strains of mosquitoes, Aedes aegypti and Culex tarsalis, to determine if biological and mechanical transmission occur . Biological transmission was not confirmed, but HC virus was retained in A aegypti for 3 days . Mechanical transmission was confirmed with A aegypti in 2 of 9 experiments. Ann Sclavo, 1975 May-Jun, 17(3), 387 - 98 {Studies on the physiopathology of cholera in Bari}; Schiraldi O et al.; During a small epidemic of cholera in South Italy in summer of 1973, the infection showed some peculiarities and differences in comparison with cholera classic picture of Asiatic areas . In this paper epidemiological, pathogenetic, clinical and biochemical data of patients admitted to the Institute of Infectious Diseases of Bari are reported . The age of the majority of patients (over 50) is an important factor for understanding cause of infection; but also preexistent basal diseases are responsible of severe course of infection . In fact, in spite of low mortality (2/70), in many cases the course of disease has been complicated by metabolic disorders . Also cardio-vascular conditions have influenced course of infection . The Authors discuss the causes of this atypic behaviour of cholera in South Italy. N Engl J Med, 1975 May 1, 292(18), 941 - 5 Pancreatic cholera: benefical effects of treatment with streptozotocin; Kahn CR et al.; Two patients with pancreatic cholera and islet-cell carcinoma were treated with intra-arterial streptozotocin . Before therapy, they had stool volumes from 2 to 8 liters per day and required 200 to 800 mEq per day of supplemental potassium . After three to five doses of streptozotocin (1.5 per square meter), both stool volume and number and size of hepatic metastases decreased markedly . One patient has had normally formed stools for 12 months; the other had a 90 per cent reduction in stool volume for 13 months with additional therapy . Both patients' serum potassium returned to normal without need for supplementation . Jejunal adenylate cyclase activity was normal in both, and plasma vasoactive intestinal peptide was detectable in only one . After chemotherapy, these findings showed no consistent change . Pharmacologic studies suggest that arterial administration increased either tumor or hepatic extraction (or both) of streptozotocin by two times and decreased renal exposure to this nephrotoxic drug by one third. Kidney Int, 1975 Mar, 7(3), 137 - 44 Renal action of cholera toxin: II . Effects on adenylate cyclase-cyclic AMP system; Kurokawa K et al.; The effects of cholera toxin (CT) on the adenylate cyclase-adenosine 3',5'-cyclic monophosphate (cAMP) system(s) in renal cortex were examined using the isolated renal cortical tubules of rat . Unlike parathyroid hormone, catecholamines or prostaglandins, CT had no immediate effects on cAMP production by the tubules or on adenylate cyclase activity . However, after 30 min of incubation at 37 C, cAMP production by the tubules started to rise and reached a plateau between 60 and 90 min . This rise in cAMP production was not abolished by protein synthesis inhibitors (actinomycin D and cycloheximide) nor by the inhibitors of prostaglandin synthesis (acetyl-salicylate and indomethacin) . Repeated washings of the tubules exposed to the toxin for five minutes at 0 or 37 C did not abolish the effect of CT to stimulate cAMP production . Assays of adenylate cyclase activity using homogenates prepared from isolated tubules which were incubated for 60 min with CT revealed an increase in the basal adenylate cyclase activity without any change in NaF-sensitive enzyme activity . It is concluded that CT binds to renal tubule cells rapidly, possibly through energy-independent process . CT stimulates adenylate cyclase activity and increases cAMP production by the renal tubule cells after a latent period of 30 min . The stimulatory effects of CT are not due to new protein synthesis or prostaglandin formation. Ann N Y Acad Sci, 1975 Feb 28, 249, 413 - 23 Stimulation of cAMP levels and modulation of antibody formation in mice immunized with cholera toxin; Kateley JR et al.; Injection of mice with 1.0 mu g of a purified exotoxin derived from Vitro cholerae together with a challenge injection of sheep erythrocytes (SRBC)P OR E . coli LPS markedly influenced the immune response to these antigens . Simultaneous injection of the toxin with antigen resulted in a delayed appearance of antibody-forming cells during the first few days after immunization, followed by a marked enhancement of the peak numbers of antibody-forming cells . In the case of the immune response to SRBC, both 19S and 7S plaque-forming cells (PFC) were enhanced on the peak day of response after simulataneous immunization of toxin-injected mice . The secondary immune response to SRBC was also similarly affected when cholera toxin was given along with a second injection of erythrocytes: i.e . a delay in appearance of the first antibody-forming cells followed by a marked enhancement of the peak 19S and 7S PFC response . Injection of cholera toxin 103 days prior to SRBC or LPS was immunosuppressive . The effect of cholera toxin on the level of splenic cyclic AMP appeared related to the effects on antibody formation. Biochim Biophys Acta, 1975 Feb 13, 381(2), 308 - 23 Stimulation of cyclic adenosine 3':5'-monophosphate and corticosterone formation in isolated rat adrenal cells by cholera enterotoxin . Comparison with the effects of ACTH; Haksar A et al.; 1 . The production of cyclic adenosine 3':5'-monophosphate (cyclic AMP) and corticosterone isolated ratadrenal cells was increased by cholera enterotoxin . Both responses were accompanied by a lag period which is characteristic of other known actions of enterotoxin . The duration of the lag period in the production of corticosterone depended on the concentration of enterotoxin; with the maximally stimulating amounts it was 30-45 min . 2 . Maximum rates of cyclic AMP and corticosterone synthesis, after the lag period, were constant for at least 1 h . Although the maximum rate of corticosterone formation was the same as that obtained adrenocorticotropic hormone, the maximum rate of cyclic AMP formation was only 8-10% of that with adrenocorticotropic hormone . 3 . Pretreatment of the cells with enterotoxin ahd no effect on their subsequent steroidogenic response to maximally stimulating amounts of adrenocorticotropic hormone . 4 . Cycloheximide inhibited the effect of both enterotoxin and adrenocorticotropic hormone on corticosterone production . 5 . Enterotoxin stimulation of both cyclic AMP and corticosterone formation was dependent on the presence of Ca2+ in the medium although the Ca2+ requirement was not same as that for adrenocorticotropic hormone . Thus, EGTA at concentrations which completely abolished the effect of adrenocorticotropic hormone caused only a partial reduction in the effects of enterotoxin . 6 . Exogenously added choleragenoid and gangliosides abolished the effects of enterotoxin without having any significant effect on the response of the cells to adrenocorticotropic hormone . 7 . After treatment with neuraminidase, the adrenal cells showed an increased response to enterotoxin in terms of both cyclic AMP and corticosterone formation which was due to a combination of two effects: (a) increased rate of synthesis of both compounds and (b) shortening of the characteristic lag period . This is in sharp contrast to the results obtained with adrenocorticotropic hormone where neuraminidase-treatment made the cells less sensitive to adrenocorticotropic hormone. J Immunol, 1975 Feb, 114(2 Pt 1), 665 - 70 Lymphocyte depletion induced by cholera toxin; relationship to adrenal cortical function; Morse SI et al.; Intravenous injection of cholera toxin (choleragen) into mice caused a profound lymphocytopenia associated with marked cellular depletion of the lymph nodes, spleen, and thymus . After administration of 1 mu g of choleragen, lymphocytopenia was mot marked at 24 hr; recovery occurred 6 to 10 days later . Similarly depletion of lymph nodes and spleen was maximal at 24 hr with recovery by 14 days . Choleragen also caused a marked elevation of serum corticosterone and lymphocyte depletion was not observed in adrenalectomized mice . These results suggested that the lymphocytopenic effect of choleragen was mediated by increased production and secretion of adrenal cortical hormones secondary to a rise in intracellular cAMP induced by cholera toxin . The site of action of choleragen may be the adrenal cortex itself and/or the hypothalamic-pituitary system. Am J Vet Res, 1975 Feb, 36(2), 141 - 4 Swine buffy coat culture: an aid to the laboratory diagnosis of hog cholera; Kresse JI et al.; A 2-step technique for the isolation of hog cholera (HC) virus consisting of an initial culture on buffy coat (BC) cultures and subinoculation to a pig kidney cell line (PK-15) was described . By this technique, HC virus was confirmed in specimens from 65 herds in which the conventional cell culture isolation technique failed . The herds were located in 20 states and Puerto Rico . Specimens from 29 of the 65 herds were inoculated into specific-pathogen-free (SPF) pigs . Hog cholera virus was recovered from 27 of the test pigs . The 2 pigs from which virus was not recovered had signs of acute infection and, on necropsy, had gross lesions of HC infection. J Biol Chem, 1975 Jan 25, 250(2), 488 - 500 Membrane receptors as general markers for plasma membrane isolation procedures . The use of 125-I-labeled wheat germ agglutinin, insulin, and cholera toxin; Chang KJ et al.; Specific cell surface membrane receptors, labeled by forming a complex with low concentrations (about 10--9 M to 10--10 M) of a highly radioactive (125-I, carrier-free) ligand, can serve as simple, reliable, sensitive, and quantitative markers for plasma membranes in fractionation procedures . 125-I-Labeled insulin, cholera toxin and the plant lictins, wheat germ agglutinin (WGA), and concanavalin A are the receptor ligands used for labeling plasma membranes . Plasma membranes are labeled before homogenization by incubating intact cells briefly at 24 degrees or 4 degrees, or by very brief in situ perfusion of the organ, with the 125-I-Labeled marker . After removing the free 125-I-labeled ligand from the medium by washing (at 4 degrees), the membrane-marker complex remains intact over prolonged (days) periods of time at 4 degrees . Labeling occurs nearly exclusively on the cell surface, the specificity of this plasma membrane reaction is maintained through homogenization and fractionation, and little dissociation of the complex, detectable exchange of label, or aggregation occur even upon prolonged incubation of the homogenates . When desired, the complex can be dissociated deliberately by manipulating experimental conditions such as temperature or by adding specific simple sugars . The most generally suitable marker appears to be WGA . At least in certain tissues (e . g . fat cells) labeling of the plasma membrane with 125-I-WGA and 125-I-isnulin can be performed equally well and selectively in homogenates as in the intact cell . 125-I-Cholera toxin cannot be used in homogenates because of significant binding to nuclei . The use of 125-I-labeled WGA as a specific plasma membrane marker is illustrated in following the course of fractionations, and in quantitating the yield and purity, of plasma membranes from fat cells, lymphocytes, and liver . The results are compared with simultaneous measurements of the plasma membrane enzyme "markers," ATPase, 5-nucleotidase, and basal as well as hormone-stimulated adenylate cyclase activities . The fractionation of liver plasma membranes by aqueous dextran-polyethylene glycol two-phase polymer systems and by conventional differential centrifugation procedures arealso quantitated with the marker, 125I-WGA . Substantial quantities of plasma membrane material are no recovered in the interphase of the two-phase polymer system . Conventional liver fractionation procedures which retain, for further purification, only the readily sedimented pellet (2000 times g, 15 min) discard a very large (at least 70%) questenal hy Vet Med Nauki, 1975, 12(9), 40 - 5 {Antibody formation in swine vaccinated with a lapinized K-vaccine and serum against hog cholera}; Dimitrov K et al.; Immunized were experimentally a total of 10 pigs with 2 cu . cm lapinized K vaccine and 10 cu . cm swine fever serum each . Reimmunization was performed a month later using only vaccine . After three and a half months the experimental pigs were included into the group of pigs producing serum against swine fever that were preliminary simultaneously immunized against hog cholera by the classical method . Swine fever antibodies in the serum of the experimental pigs showed a concentration that was equal to that in the serum of the regular donors as in both cases the serum titer ranged within the limits of 0.10 to 0.12 cu . cm per kilogram body weight . It is concluded that pigs intended for serum producers can be immunized with a lapinized K vaccine and serum against swine fever on the farms supplying the animals . After building up the basic immunity, which lasts about three and a half months the pigs could be bought over and included for serum production . Thus, the pathogenic hog cholera virus of the simultaneous immunization at the Institute (producer of serum) will be eliminated, economizing forage and labor and premises for several months, which are necessary for serum producing pigs. Physiol Chem Phys, 1975, 7(6), 533 - 9 The effects of cholera enterotoxin on intestinal tissue water as measured by nuclear magnetic resonance (NMR) spectroscopy; Udall JN et al.; Cholera enterotoxin has been postulated to change the configuration of the intracellular protein-water system, altering the permeability of the cell to water . Using nuclear magnetic resonance (NMR) spectroscopy, this protein-water relationship can be examined . Small intestinal loops in the rat were injected with 0.5 ml of either Schwarz/Mann cholera enterotoxin (40 mug/cc saline solution) or normal saline . Full thickness segments of intestine from each loop were taken and percentage water (using a gravimetric procedure which includes a correction for fat) and NMR relaxation times were determined . The mean value +/- S.D . for tissue water was 79.49 +/- 2.65% in the controls and 84.52 +/- 2.01% in the cholera specimens (p less than .001) . T1 (spin-lattice) relaxation times were 521.22 +/- 69.5 msec in the controls and 667.96 +/- 119.25 msec in cholera tissue (p less than .001) . T2 (spin-spin) relaxation times were 62.34 +/- 9.59 msec in controls and 80.35 +/- 21.46 msec in cholera tissue (p less than .02) . These findings are consistent with the theory that cholera enterotoxin acts to alter intracellular protein-water relationship. Zentralbl Bakteriol {Orig B}, 1975, 160(1), 1 - 27 Socio-economic and environmental factors and human health example of cholera El Tor in Manila; Velimirovic B et al.; The environmental health factors relevant to the occurrence of cholera in an urban milieu (Manila) have been studied . Cholera has been found to be a disease significantly more prevalent in the areas with lowest environmental condition . Association have been found between the disease incidence and several socioeconomic variables: population density, water and sewer connections each per 1000 population and squatter/slum dweller density . The correlation between cholera incidence and population density was found to be statistically significant at 5% level . A multiple regression analysis showed that the variations in cholera incidence were explained to the extent of 53.23% by the three variables-population density, water and sewer connections . In a check, using data for several years, positive correlations were found between incidence rates and the number of persons per sanitary facility, overcrowding, and density per square kilometer . The association between cholera and the low levels of socioeconomic conditions has been examined in a detailed study of a sample of 711 patients during the cholera season 1971-72 . The socioeconomic profile of the sample places the patients in the least affluent part of the community . - The paper points out the need for priority of urban redevelopment in areas of maximum health risk. Biochem J, 1975 Jan, 146(1), 269 - 71 Short communications . Subunit A from cholera toxin is an activator of adenylate cyclase in pigeon erythrocytes; Van Heyningen S et al.; Intact cholera toxin and its purified subunit A both activate the adenylate cyclase of pigeon erythrocyte membranes, but subunit B does not . The activation by subunit A is unaffected by treatments that inhibit whole toxin by interfering with the binding of subunit B to cell membranes. Vopr Virusol, 1975 Jan-Feb, (1), 34 - 9 {Serological study of the neuraminidase activity of cholera filtrate and influenza virus}; Gutman NR et al.; The capacity of homologous (influenza virus) and heterologous (V . cholerae) anti-neuraminidase antibody to neutralize the neuraminidase activity of influenza virus was studied . The lack of antigenic relationship between the enzyme of V . cholerae and that of influenza virus was established and differences in the antigenic structure of neuraminidase of influenza virus of both different types (A0, A1, A2) and within one type were demonstrated. Gastroenterology, 1975 Jan, 68(1), 94 - 104 Adenylate cyclase in intestinal crypt and villus cells: stimulation by cholera enterotoxin and prostaglandin E1; Schwartz CJ et al.; The secretory responses to cholera enterotoxin and prostaglandin E1 (PGE1) are dependent upon elevation of the intracellular levels of cyclic AMP . Although several previous reports have suggested that intestinal secretion due to cholera enterotoxin and PGE1 may be confined to the crypt cells, this matter has been incompletely resolved . These studies were undertaken to define the activity of adenylate cyclase in villus and crypt cells from rabbit and rat intestine, and to determine the influence of enterotoxin and PGE1 on this activity, Mucosal fractions were prepared from rabbit ileum with a planing device, and from rat distal small intestine by a vibration technique . In both species base line adenylate cyclase activity was greater in crypt than in villus cells . After exposure to cholera enterotoxin in vivo, adenylate cyclase activity was enhanced in all fractions prepared from rabbit ileum, and the response was most marked in villus cells . Furthermore, adenylate cyclase in membranes prepared from both rat villus and crypt intestinal cells was responsive to the in vitro addition of PGE1 . The results of these studies indicate that both villus and crypt cells contain one of the important components required for the cyclic AMP-mediated secretory response, namely, a cholera enterotoxin and PGE1-sensitive adenylate cyclase activity . Since an increased level of cyclic AMP alone may not be sufficient to evoke a secretory response, these studies do not clarify the extent to which each of these major cell types may participate in cyclic AMP-mediated secretion. Antonie Van Leeuwenhoek, 1975, 41(1), 69 - 79 Scanning isoelectric focusing of cholera enterotoxin in polyacrylamide gels; Yotis WW et al.; Scanning isoelectric focusing has been employed for continuous monitoring of the isoelectric spectrum of highly purified cholera enterotoxin in 4% polyacrylamide gels containing 2% ampholytes pH 3-10 . The resolution obtained by this technique is of high order because at no instance during focusing interruption of current occurs and thus diffusion of the isolated protein moieties is suppressed . An added aspect of scanning isoelectric focusing was that it allowed estimation of the minimal focusing time of cholera enterotoxin . Thus under the standard assay procedure, the main basic component of cholera enterotoxin was focused in 5800 sec, while the other at least 3 minor acidic and anodic components were focused in approximately 19000 sec . Focusing of cholera enterotoxin in the presence of 6 mu urea allowed the visualization of 5 well defined and about equal components . The proteinaceous nature of the observed peaks was verified by scanning at wavelenghts other than 280 nm, staining of gels for protein, and varying the concentration of the enterotoxin . The design of scanning isoelectric focusing equipment is presented . Reproducibility, economy of sample, and ampholytes and simplicity of experimental technique were some of the features of this apparatus . The resolution of scanning isoelectric focusing was found to be superior to that of ordinary disc and SDS gel electrophoresis. J Gen Microbiol, 1975 Jan, 86(1), 49 - 65 Oligomeric structure of cholera toxin: characteristics of the H and L subunits; Holmgren J et al.; Structural analysis of cholera toxin by sodium dodecylsulphate polyacrylamide electrophoresis demonstrated two types of non-covalentyly linked subunits, heavy (H) AND LIGHT (L), with respective molecular weights 28000 and 800 to 9000 . The H:L protein ratio was I:2, indicating that the toxin of molecular weights of in ratio was I:2, indicating that the toxin of molecular weight 84000 consists of IH and 6 or 7 L subunits, linked into an aggregate with non-covalent bonds . Choleragenoid toxoid, a natural toxin derivative, contained only the L subunits of the toxin . Reduction and alkylation cleaved the H but not the L subunit . The specific clevage of the Hsubunit by reduction appeared to yield identical half-molecules; the smaller peptide seemed to originate from non-specific degradation . The H subunit also differed from L subunits by having a higher affinity for labelling with radioactive iodine and by precipitating below PH.3-5 . In immunodiffusion studies the toxin possessed antigenic determinants shared with the toxoid as well as toxin-specific determinants . Comparative analyses with purified subunit preparations revealed that the toxoid-shared determinants reside in the L-type of subunit and the toxin-specific ones in the H subunit . By precipitation-in-gel, binding to ganglioside-coated tubes, and sodium dodecylsulphate polyacrylamide electrophoresis it was demonstrated that the ability of toxin to attach to the apparent receptor ganglioside, Gm1, is similar to that of choleragenoid toxoid, and is due to the Gm1-binding ability of the L subunits . The toxin Hsubunit did not react with the Gm1 ganglisoside.The results support our previous structural model for cholera toxin, and explain the antigenic and receptor-binding properties of the toxin in terms of component subunits. Proc Soc Exp Biol Med, 1975 Jan, 148(1), 19 - 24 Elevated cyclic AMP levels in mouse lymphoid tissue after stimulation by cholera enterotoxin in vitro (38468) Kateley JR, Kasarov L, Friedman H. Addition of CT to suspensions of thymus, lymph node, spleen, or bone marrow cells in vitro resulted in a marked accumulation of cAMP with peak levels occurring 4-5 hr after incubation of cells with CT . Thymus cells showed the largest increase in cAMP, approximately 40-fold at 10 ng/ml CT . Bone marrow cells accumulated the least cAMP (1.5x), while intermediate levels were observed for spleen and lymph node cells (10-12x) . Antiserum to CT prevented stimulation of increased cAMP levels . Repopulation studies using X-irradiated mice also showed that thymus-derived spleen cells accumulated more cAMP/10-7 cells than spleen cells from recipients given spleen or marrow cells . Spleen cells from athymic (nu/nu) mice also responded much less than did spleen cells from normal mice . Thymocytes appeared to bind CT to a greater degree than bone marrow cells . Spleen and lymph node cell suspensions also contained CT-binding cells and the number of CT-binding cells in these peripheral lymphoid tissues appeared approximately equal to the summation of the numbers observed in thymocyte and bone marrow cell suspensions . Stimulation of cAMP in lymphoid cells, especially thymocytes, by CT provides a pharmacological tool to investigate the mechanism and role of this nucleotide in the early events of antibody formation. Proc Natl Acad Sci U S A, 1975 Jan, 72(1), 33 - 7 Mechanism of action of cholera toxin and the mobile receptor theory of hormone receptor-adenylate cyclase interactions; Bennett V et al.; Rat liver membrane adenylate cyclase (EC 4.6.1.1) that has been stimulated more than 10-fold by cholera toxin (choleragen) has a 3-fold greater sensitivity to stimulation by glucagon . Choleragen similarly increases the sensitivity of cyclase to other peptide (ACTH, vasoactive intestinal polypeptide) and nonpeptide (catecholamines) hormones in this and other tissues . The rate of 125I-labeled glucagon-membrane dissociation is decreased about 2-fold in toxin-treated liver membranes . Toxin-activated cyclase activity of fat cell membranes is retained upon solubilization with Lubrol PX . Provided 125I-labeled choleragen is first incubated with cells under conditions resulting in enzyme activation, the solubilized cyclase activity migrates with a component of 125I-labeled choleragen on gel filtration chromatography . Agarose derivatives containing the "active" subunit (molecular weight 36,000) of the toxin can specifically adsorb solubilized adenylate cyclase . Toxin-stimulated cyclase can be immunoprecipitated with antitoxin or anti-"active" subunit antibodies . There is a large excess of membrane receptors (ganglioside GM1) which, with the use of choleragenoid, can be shown to be functionally equivalent with respect to cyclase activation . Choleragenoid, an inactive competitive antagonist of toxin binding, can occupy and block a large proportion of toxin receptors without affecting toxin activity . A scheme of toxin action is proposed that involves lateral membrane diffusion of the initially inactive toxin-receptor complex with subsequent direct interaction with and modulation of adenylate cyclase . The basic features of this scheme may be pertinent to the mechanisms by which hormone receptors normally modulate adenylate cyclase. J Immunol, 1975 Jan, 114(1 Pt 2), 426 - 34 Regulation of the in vitro early anamnestic antibody response by exogenous cholera enterotoxin and cyclic AMP; Cook RG et al.; Keyhole limpet hemocyanin was injected into the hind foot pads of rabbits . Six days later cell suspensions were prepared from the popliteal lymph nodes . Various amounts of hemocyanin (1 ng to 100 mug) were added to 1 times 10-7 cells to induce an anamnestic antibody response . Various amounts of cholera enterotoxin, which stimulates the enzyme adenylate cyclase, or dibutyryl cyclic adenosine 3'5'-monophosphate (AMP), were added to the cultures with or without hemocyanin . De novo synthesis of antibody, protein, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) from radioactive precursors was assayed . The addition of cholera toxin or dibutyryl cyclic AMP for the first 24 hr with optimal (1 mug) or supraoptimal (100 mug) amounts of hemocyanin enhanced antibody synthesis by at least 100 to 200% . Addition of the toxin or dibutyryl cyclic AMP for the same period to cells minus hemocyanin or with suboptimal amounts (1 to 100 ng) of antigen failed to enhance antibody synthesis . Addition of these agents for 72 to 120 hr to hemocyanin-induced cultures consistently inhibited antibody synthesis . These agents slightly inhibited DNA and RNA synthesis . The increase in protein synthesis caused by the toxin or dibutyryl cyclic AMP was almost totally accounted for by the increase in antibody synthesis . Neither toxin nor cyclic nucleotide promoted the antibody response in the presence of antibody to rabbit thymus-derived lymphocytes; these lymphocytes as well as bursa-equivalent lymphocytes were required for potentiation of the response . Macrophages were not required either for induction of the anamnestic response or for enhancement of this synthesis by cyclic nucleotide or cholera toxin . Both IgM and IgG antibody synthesis were regulated by exogenous cholera toxin and dibutyryl cyclic AMP . A number of possible cellular mechanisms of regulation of the antibody response through the cyclic AMP pathway were discussed . These included the effects of modifications of this pathway on the activities of T lymphocytes early (0 to 24 hr) and B lymphocytes late (72 to 120 hr) in the response and on the apparent reversal of high zone tolerance. J Neurol, 1975, 209(1), 69 - 74 {A case of Guillain-Barré syndrome following cholera vaccination (author's transl)}; Schrader H; A 45-year-old woman developed bilateral ascending flaccid paralysis after cholera vaccination, 15 days after the first and 1 day after the second injection . The clinical course resulted in nearly complete paralysis of the lower limbs, paresis of the upper limbs and partial involvement of the cranial nerves . There was only slight sensory loss . The CSF revealed no pleocytosis and a protein level of 206 mg/100 ml . Recovery began 2 weeks later and was almost complete after 2 months . Immunological investigations revealed no remarkable changes. Am J Epidemiol, 1974 Dec, 100(6), 487 - 98 A case of cholera in Texas, 1973; Weissman JB et al.; The first naturally acquired case of cholera reported in the United States since 1911 occurred in a 51-year-old resident of Port Lavaca, Texas . Extensive epidemiologic investigation of the patient's contacts and environment did not identify a cholera carrier of elucidate a pathway of transmission, but several avenues of investigation suggested possible means by which the patient may have acquired his infection . No secondary spread resulted from this case, and its occurrence did not endanger the community at large. Trans R Soc Trop Med Hyg, 1970, 64(5), 769 - 71 Oral or nasogastric maintenance therapy for diarrhoea of unknown aetiology resembling cholera; Nalin DR et al.; PIP: Clinical trials under field hospital conditions were undertaken in India and Pakistan to determine the efficacy of oral maintenance solutions in treatment of noncholera diarrheal patients . Those patients with severe dehydration due to diarrhea were 1st rehydrated with a standard intravenous solution until the blood pressure was normal . They were then administered a warmed maintenance solution by mouth or nasogastric tube . Milder cases were given only an oral solution . The oral treatment was found to maintain fluid balance in all cases . Oral electrolyte solutions containing both glucose and glycine produced lower total stool volumes than the solutions made up only of electrolytes and glucose . The addition of glycine to the solution seems to enhance absorption . This oral therapy is recommended because the solution is cheap and the ingredients are widely available . Both solutions eliminated the need for intravenous fluids in 80% of the cases, thus lowering the number of staff man-hours needed per patient . This treatment can, thus, lower total costs and increase availability of diarrhea treatment in developing countries where severe diarrheal diseases are common . Bull World Health Organ, 1970, 43(3), 361 - 3 Oral (or nasogastric) maintenance therapy for cholera patients in all age-groups; Nalin DR et al.; PIP: 56 children and 50 adults were studied to determine the effectiveness of an oral (or nasogastric) therapy with a glucose-electrolyte solution for treating cholera patients . The development of this inexpensive regimen is described . The therapy has the advantages of being cheap, not requiring sterile conditions, and having wide availability in endemic areas . The oral solution contained the following ions (as milliequivalents per liter of water): Na+, 120 K+, 25; CO2-, 48; CL-, 97; and glucose at 110 mmol/liter . Patients received nothing orally except the solution and a 5-day course of tetracycline (dosed according to body weight) . The oral (or nasogastric) therapy was used as a supplement when patients arrived in shock, at which time intravenous infusion was used to begin rehydration; patients with milder cholera cases were given only the oral therapy, with much success . All children were maintained in a positive balance with the oral (or nasogastric) solution after correction of shock by intravenous rehydration, and the mean volume of oral solution required by the 56 children was 6 liters . In field trials, 80% of the patients were in positive net intestinal balance by 6 hours after initiation of oral therapy . Adults studied to determine in the 25 mEq potassium/liter solution was safe showed that after administration adult plasma potassium levels were normal . N Engl J Med, 1968 Jul 25, 279(4), 176 - 81 Decrease in net stool output in cholera during intestinal perfusion with glucose-containing solutions; Hirschhorn N et al.; PIP: Glucose-electrolyte solutions were administered to cholera patients by intestinal tube and the effect of this treatment on net stool output was assessed; an ancillary concern was the comparison of the sugar used in the rehydration solution, comparing glucose, galactose, and fructose . All 8 patients studied were cholera victims who had been given intravenous rehydration upon presentation with severe shock; 25 controls were studied for comparison . Average net stool rate of the controls not given perfusions declined at an approximately linear rate throughout the course of diarrhea . However, in every case when glucose was added to perfusion solution, net stool output decreased compared with the decline seen in the total course of non-sugar-containing per fusion studies . In fact, the rate of intestinal fluid loss was decreased with the glucose solution within 12-32 hours of perfusion . Since intestinal sodium absorption was so enhanced by an actively transported sugar, fructose and galactose perfusion fluids were prepared, and it was found that fructose was less well absorbed than glucose or galactose: in general, the results with these sugars were consistent with the sodium-dependent active transport of galactose and the passive transport of fructose, unrelated to sodium transport . Indian J Med Res, 1968 May, 56(5), 640 - 5 Oral maintenance of water-electrolyte and acid-base balance in cholera: a preliminary report; Pierce NF et al.; PIP: A study was undertaken to determine whether the absorption of glucose from the normal small bowel also involves increased absorption of sodium and water . 9 adult males suffering from severe cholera were studied . They were divided into 2 groups, each of which received a different oral electrolyte solution, on an alternating schedule with control periods of intravenous fluid therapy . The solution formulae are tabulated . Balance data and study results are tabulated . The study shows that water and electrolytes were absorbed from both the glucose-electrolyte solutions studied . Increased content of glucose in the solution reduced the amount of fluid necessary to maintain the fluid balance . This study leads to a conclusion that orally-administered glucose-electrolyte solutions can be valuable in cholera management, especially in situations where intravenous fluids are insufficient or inappropriate or where personnel skilled in their administration are lacking .
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