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1.
Acta Psychiatr Scand ; 122(3): 226-34, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20085556

RESUMO

OBJECTIVE: To evaluate psychometric properties and comparability ability of the Montgomery-Asberg Depression Rating Scale (MADRS) vs. the Quick Inventory of Depressive Symptomatology-Clinician-rated (QIDS-C(16)) and Self-report (QIDS-SR(16)) scales to detect a current major depressive episode in the elderly. METHOD: Community and clinic subjects (age >or=60 years) were administered the Mini-International Neuropsychiatric Interview (MINI) for DSM-IV and three depression scales randomly. Statistics included classical test and Samejima item response theories, factor analyzes, and receiver operating characteristic methods. RESULTS: In 229 elderly patients (mean age = 73 years, 39% male, 54% current depression), all three scales were unidimensional and with nearly equal Cronbach alpha reliability (0.85-0.89). Each scale discriminated persons with major depression from the non-depressed, but the QIDS-C(16) was slightly more accurate. CONCLUSION: All three tests are valid for detecting geriatric major depression with the QIDS-C(16) being slightly better. Self-rated QIDS-SR(16) is recommended as a screening tool as it is least expensive and least time consuming.


Assuntos
Transtorno Depressivo Maior/diagnóstico , Determinação da Personalidade/estatística & dados numéricos , Inventário de Personalidade/estatística & dados numéricos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Masculino , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Psicometria/estatística & dados numéricos , Curva ROC , Reprodutibilidade dos Testes
2.
J Stud Alcohol ; 37(1): 1-10, 1976 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2808

RESUMO

Hypoglycemia resulting from intragastric infusion of ethanol in miniature swine was counteracted by simultaneous infusion of fructose. The magnitude and time of peak plasma ethanol concentrations were functions of the quantity of ethanol or ethanol and fructose.


Assuntos
Glicemia/análise , Etanol/farmacologia , Frutose/farmacologia , Suínos/sangue , Animais , Relação Dose-Resposta a Droga , Interações Medicamentosas , Etanol/administração & dosagem , Frutose/administração & dosagem , Hemoglobinas/análise , Hipoglicemia/induzido quimicamente , Intubação Gastrointestinal , Fatores de Tempo
3.
J Psychoactive Drugs ; 26(2): 207-16, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7931865

RESUMO

Increasing the availability of, and streamlining the admissions process to, methadone treatment have consistently been the focus of national plans to address the acquired immune deficiency syndrome (AIDS) epidemic. This article uses simplified time-series analysis to evaluate one of the first methadone treatment Waiting List Reduction Demonstration Grants. The demonstration grant significantly increased both the number of people requesting intake appointments from 35 to 100 per month and the percentage of kept appointments from 33% to 54%. An additional 100 slots (an entire year's waiting list) were filled in fewer than three months and actually resulted in a net increase in the length of the waiting list. Relative to the preceding two years, new clients during the grant period were significantly more likely to be 41 or older, African-American, unemployed, daily opioid users, daily cocaine users, and dependent on public assistance to finance treatment. Controlling for the source of treatment financing (a case-mix adjustment), there were no significant changes in retention rates. The program's static client capacity rose from 310 prior to the grant to a peak of 449 during the grant, with a leveling to 410 after the grant. Given that it is clearly more humane and less expensive to treat people who want treatment rather than wait for them to commit a crime and be arrested or even executed, this study strongly suggests the need to make more treatment available on demand.


Assuntos
Dependência de Heroína/reabilitação , Metadona/uso terapêutico , Cooperação do Paciente , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Adulto , Feminino , Dependência de Heroína/psicologia , Humanos , Tábuas de Vida , Masculino , Assunção de Riscos
7.
J Clin Microbiol ; 25(4): 702-5, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3553233

RESUMO

Twenty-five strains of Salmonella typhimurium isolated in India were examined for the presence of cholera/coli-related enterotoxin antigen by a previously described latex particle agglutination test and by a newly developed immuno-dot-blot test using immunopurified goat antibody against the cholera-related enterotoxin isolated from an Escherichia coli strain of human origin. The immuno-dot-blot assay could detect 0.02 ng of purified enterotoxin. The amount of toxin antigen detected varied widely from strain to strain. Fourteen of the 25 polymyxin B-treated extracts of bacteria harvested from 6-h Casamino Acids-yeast extract broth cultures gave positive results in both serologic assays as well as in rabbit skin tests for delayed permeability factor. An additional strain was positive only in the immuno-dot-blot. Five of six stool isolates and six of seven blood isolates tested gave positive reactions. Two isolates of Salmonella enteritidis tested were also positive. The immuno-dot-blot test appears to be a simple, rapid, and reliable method for detection of cholera-related enterotoxin antigen in S. typhimurium. The demonstration of a cholera-related enterotoxin, even in small amounts, in a facultative intracellular pathogen raises interesting questions regarding its potential role in pathogenesis both of diarrheal disease and systemic infections caused by salmonellae.


Assuntos
Antígenos de Bactérias/análise , Toxinas Bacterianas/análise , Endotoxinas , Enterotoxinas/análise , Proteínas de Escherichia coli , Salmonella typhimurium , Animais , Toxinas Bacterianas/imunologia , Enterotoxinas/imunologia , Humanos , Técnicas Imunológicas , Testes de Fixação do Látex , Coelhos , Salmonella typhimurium/imunologia
8.
J Chem Ecol ; 13(5): 1087-97, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-24302134

RESUMO

The Rose-of-Sharon,Hibiscus syriacus (L.), can be a significant alternate host plant for the boll weevil,Anthonomus gradis (Boh.). Boll weevils are known to be deterred from feeding and ovipositing in the buds unless the calyx is removed. This investigation was initiated to identify calyx allelochemicals that deter feeding with the eventual strategy of breeding for cotton lines high in these allelochemicals in the appropriate tissues. The feeding deterrency of calyx tissue from the buds of Rose-of-Sharon for the boll weevil was confirmed. The most active deterrent fraction was found to contain mostly fatty acids and their methyl esters. Saturated fatty acids and their methyl esters were generally found to be stimulatory, while the unsaturated species were found to be deterrent. Higher quantities of the fatty acids, particularly the unsaturated species, were found in Rose-of-Sharon calyx tissue than in the buds without calyx. This supports the hypothesis developed through the isolational work and testing of standards that the unsaturated fatty acids are significant deterrents of boll weevil feeding.

9.
Plant J ; 11(6): 1359-68, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9225474

RESUMO

Barley aleurain is contained within a specific type of vacuole characterized by acidic pH and the presence of other hydrolytic enzymes. The aleurain-containing vacuole is distinct from protein storage vacuoles, and anti-aleurain antibodies serve as markers for this organelle in barley cells. Aleurain is a unique type of cysteine protease, and other plant species have genes for homologs whose sequences are highly conserved, but little is known about these homologs at the protein level. Seven monoclonal antibodies to barley aleurain were isolated, which bind to and define aleurain homologues in Arabidopsis, Petunia, and tobacco cell extracts. Interestingly, in addition to 29-32 kDa aleurain homologs, Petunia extracts contain a protein of approximately 50 kDa and tobacco extracts a protein of approximately 40 kDa that are recognized by multiple different monoclonal antibodies, indicating an unexpected diversity to the aleurain protein family. Among the group of antibodies are some that efficiently immunoprecipitate metabolically labeled aleurain from barley cell extracts, and some that efficiently label aleurain in immunofluorescence assays using root tip cells. These antibodies should be useful for plant cell biologists who study vacuole biogenesis and function and sorting of proteins to specific vacuolar compartments, in barley as well as other plant species.


Assuntos
Anticorpos Monoclonais/imunologia , Cisteína Endopeptidases/imunologia , Sequência de Aminoácidos , Reações Antígeno-Anticorpo , Clonagem Molecular , Sequência Conservada , Cisteína Endopeptidases/genética , Hordeum/imunologia , Hibridomas , Concentração de Íons de Hidrogênio , Microscopia Confocal , Microscopia de Fluorescência , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
10.
Growth ; 40(3): 293-300, 1976 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-976771

RESUMO

Venous blood samples were collected monthly from 60 male and 60 female Sinclair (S-1) miniature swine from 1 through 36 months of age. Serum cholesterol concentration decreased from 5 through 36 months of age. Also, gilts had a greater mean serum cholesterol concentration than did boars. Mean serum triglyceride concentration was greater for females than for males. From 1 through 15 months of age, serum glucose concentration decreased with no sex related difference. From 1 1/2 to 3 years of age, gilts had greater mean serum glucose concentrations than did boars. Throughout the longitudinal study, mean serum total bilirubin concentrations were similar for females and males, with no age related variations.


Assuntos
Bilirrubina/sangue , Glicemia/análise , Colesterol/sangue , Suínos/sangue , Triglicerídeos/sangue , Fatores Etários , Animais , Feminino , Masculino , Fatores Sexuais
11.
J Chem Ecol ; 11(4): 473-84, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24310069

RESUMO

The weights of pecanCarya illinoensis Koch galls caused by several species ofPhylloxera (Homoptera: Phylloxeridae) were negatively correlated with leaf and nut weights and nut production. Several allelochemicals (isoquercitrin, juglone, and 2 proanthocyanidins) were isolated from galls, and their antibiotic potentials were estimated, based on their toxicity to the bacteriaPseudomones maltophilia (Hugh et Ryschenkow). Pecan proanthocyanidins (condensed tannins) were characterized for the first time, and their stereochemistry was elucidated. The protein and total sugar contents of total leaves and leaf surface washings were determined. The leaf surface sugar content was very low, suggesting that the puncturing strategy of this insect may be for the purpose of finding sugars. The plant growth hormones gibberellic acid, zeatin, zeatin riboside, kinetin, indole acetic acid, and abscisic acid were found in pecan leaves, stems, and their galls. Gibberellic and abscisic acids were present in highest concentrations in all tissues, but lower in galled tissues, suggesting that increased biosynthesis by pecan plant growth regulators did not occur in response to insect attack.

12.
J Lab Clin Med ; 96(5): 922-32, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7419971

RESUMO

Acute alcohol intake produces marked damage to gastric mucosa. Whether gastric mucosa develops tolerance to repeated alcohol administration is unknown. To test this, we compared the effects of acute and chronic alcohol administration in male rats. Thirty-one Sprague-Dawley rats maintained on Chow diet received the following: group A, water for 4 weeks; group B, 50% EtOH for 4 weeks; group C, water for 4 weeks, then 8 hr prior to sacrifice 50% EtOH; group D, 50% EtOH for 4 weeks, then alcohol 8 hr prior to sacrifice. Control animals did not show macroscopic or microscopic changes in fundic or pyloric mucosa. The percentage fundic mucosa showing lesions (49%) in the acute EtOH group (group C) was significantly greater than in control (0%), chronic EtOH group (group B, 8%), and chronic plus acute EtOH (group D, 14%). Pyloric lesions were not significantly diferent between treatment groups C (9%), B (4%), and D (8%). Histologic changes in group C (acute alcohol) consisted of superficial erosions accompanied by severe hemorrhagic changes in the upper part of the gastric mucosa. In group B (chronic alcohol) and group D (chronic + acute alcohol) changes consisted of small superficial erosions without hemorrhagic changes. Our study shows that damage in rat gastrc fundic mucosa following acute intragastric administration of EtOH is significantly less in rats receiving EtOH chronically than in rats receiving only acute EtOH. We conclude that rat gastric mucosa is capable of developing tolerance to repeated administration of 50% alcohol.


Assuntos
Etanol/administração & dosagem , Mucosa Gástrica/efeitos dos fármacos , Adaptação Fisiológica , Animais , Relação Dose-Resposta a Droga , Tolerância a Medicamentos , Masculino , Ratos
13.
Dig Dis Sci ; 27(5): 394-400, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-7075426

RESUMO

The effect on parietal cells of glucagon given prior to pentagastrin is unknown. Fifteen healthy volunteers were studied during constant intravenous infusion of pentagastrin (2 micrograms/kg body weight/hr) and during pentagastrin infusion initiated 20 min after intravenous injection of 2 mg glucagon. Three types of studies were performed: Gastric mucosal biopsies were obtained with a Quinton instrument. Electron micrographs of 320 parietal cells were analyzed by the Loud quantitative method, and intragastric pH (pH probe), or gastric potential difference (PD) were recorded continuously. Pentagastrin infusion produced a significant increase in canalicular and simultaneous reduction of tubulovesicular membrane area of parietal cells. Glucagon pretreatment did not inhibit canalicular and tubulovesicular membrane reaction to pentagastrin; unexpectedly this reaction was significantly greater when compared to that after pentagastrin alone. Initiation of pentagastrin infusion in subjects pretreated with glucagon produced a greater absolute value drop in gastric PD (23 +/- 2 mV) and an earlier drop in intragastric pH (3 min) than in subjects receiving pentagastrin infusion alone (13 +/- 1 mV and 10 min, respectively). In conclusion, at the doses studied, glucagon pretreatment increases parietal cell canalicular reaction to pentagastrin.


Assuntos
Mucosa Gástrica/efeitos dos fármacos , Glucagon/farmacologia , Pentagastrina/farmacologia , Adulto , Interações Medicamentosas , Feminino , Determinação da Acidez Gástrica , Mucosa Gástrica/citologia , Mucosa Gástrica/ultraestrutura , Humanos , Masculino , Potenciais da Membrana/efeitos dos fármacos
14.
J Biol Chem ; 259(23): 14586-90, 1984 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-6334084

RESUMO

Human renal dipeptidase has been concentrated from kidneys by homogenization, 1-butanol solubilization, and (NH4)2SO4 fractionation. Final purification was achieved by high-pressure liquid chromatography followed by affinity chromatography. The enzyme appeared to be homogeneous by polyacrylamide gel electrophoresis, and its molecular weight was estimated to be 220,000 by analytical high-pressure liquid chromatography. The molecular weight of human urinary dipeptidase was estimated by agarose gel filtration to be 218,000. Dissociation of human renal dipeptidase in sodium dodecyl sulfate-polyacrylamide gel electrophoresis produced a single polypeptide (Mr 59,000). These results suggest that the native enzyme contains four subunits of Mr 59,000. Analysis of the peptidase for zinc content gave 3.9 g atoms of zinc/mol of enzyme which supports the suggestion of a 4-subunit structure. Carbohydrate analyses of the purified human dipeptidase demonstrated that it was not a glycoprotein, a characteristic that distinguishes it from porcine and rat renal dipeptidase. beta-Lactamase activity of the purified human enzyme was demonstrated by measuring its activity against the two beta-lactam antibiotics, imipenem and SCH 29482. Kinetic analyses indicated that both antibiotics undergo enzyme-catalyzed hydrolysis at rates which could produce inactivation of the antibiotics within the human kidney. The beta-lactamase inhibitor, cilastatin, demonstrated reversible competitive inhibition of the peptidase-catalyzed hydrolysis of both antibiotics with the same Ki of 0.7 microM.


Assuntos
Dipeptidases/isolamento & purificação , Córtex Renal/enzimologia , beta-Lactamases , Carboidratos/análise , Cromatografia Líquida de Alta Pressão , Dipeptidases/metabolismo , Humanos , Cinética , Substâncias Macromoleculares , Peso Molecular , Zinco/análise
15.
Am J Hum Genet ; 55(4): 777-87, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7942856

RESUMO

Human genetic maps have made quantum leaps in the past few years, because of the characterization of > 2,000 CA dinucleotide repeat loci: these PCR-based markers offer extraordinarily high PIC, and within the next year their density is expected to reach intervals of a few centimorgans per marker. These new genetic maps open new avenues for disease gene research, including large-scale genotyping for both simple and complex disease loci. However, the allele patterns of many dinucleotide repeat loci can be complex and difficult to interpret, with genotyping errors a recognized problem. Furthermore, the possibility of genotyping individuals at hundreds or thousands of polymorphic loci requires improvements in data handling and analysis. The automation of genotyping and analysis of computer-derived haplotypes would remove many of the barriers preventing optimal use of dense and informative dinucleotide genetic maps. Toward this end, we have automated the allele identification, genotyping, phase determinations, and inheritance consistency checks generated by four CA repeats within the 2.5-Mbp, 10-cM X-linked dystrophin gene, using fluorescein-labeled multiplexed PCR products analyzed on automated sequencers. The described algorithms can deconvolute and resolve closely spaced alleles, despite interfering stutter noise; set phase in females; propagate the phase through the family; and identify recombination events. We show the implementation of these algorithms for the completely automated interpretation of allele data and risk assessment for five Duchenne/Becker muscular dystrophy families. The described approach can be scaled up to perform genome-based analyses with hundreds or thousands of CA-repeat loci, using multiple fluorophors on automated sequencers.


Assuntos
Alelos , Triagem de Portadores Genéticos , Distrofias Musculares/genética , Recombinação Genética , Automação/métodos , Feminino , Técnicas Genéticas , Humanos , Masculino , Matemática , Modelos Genéticos , Distrofias Musculares/diagnóstico , Linhagem , Fenótipo , Reação em Cadeia da Polimerase/métodos , Sequências Repetitivas de Ácido Nucleico
16.
Lancet ; 2(8195 pt 1): 609-12, 1980 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-6107406

RESUMO

To determine whether the topical or systemic effects of aspirin are of greater importance in the production of gastroduodenal mucosal damage, the effects of regular and enteric-coated aspirin were compared in 9 healthy volunteers in a 2-week crossover endoscopic study. All subjects developed multiple gastric erosions while taking regular aspirin; 2 subjects developed one gastric erosion each while taking enteric-coated aspirin. 5 subjects developed duodenal erosions while taking regular aspirin, whereas none developed an erosion while taking enteric-coated aspirin. Mean fasting salicylate levels were similar in the two groups. It is concluded that regular aspirin causes a greater amount of gastroduodenal mucosal damage than does enteric-coated aspirin despite similar serum-salicylate levels. This suggests that the topical effects of aspirin are of greater importance than the systemic effects in the production of gastroduodenal mucosal damage in healthy subjects.


Assuntos
Aspirina/efeitos adversos , Mucosa Gástrica/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Adulto , Duodenopatias/induzido quimicamente , Duodeno/efeitos dos fármacos , Eritema/induzido quimicamente , Humanos , Antro Pilórico/efeitos dos fármacos , Salicilatos/sangue , Gastropatias/induzido quimicamente , Comprimidos com Revestimento Entérico
17.
Rev Infect Dis ; 9 Suppl 5: S490-502, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2446368

RESUMO

Hybridoma-derived monoclonal antibodies were raised to enterotoxins of the cholera family and to chimeric B-subunit proteins in which individual amino acid residues of a heat-labile, cholera-related enterotoxin from an Escherichia coli strain of porcine origin (P-LT) were substituted with corresponding residues from such an enterotoxin from an E. coli strain of human origin (H-LT). Single amino acid substitutions were found to have profound effects on the physicochemical behavior of the proteins and on their immunologic reactivity. With the use of enzyme-linked immunosorption assays (ELISAs) with and without the GM1 ganglioside receptor for these toxins, several distinct epitopes in GM1-binding domains were identified by different monoclonal antibodies. Polyclonal rabbit antisera to synthetic peptides of the cholera enterotoxin B subunit were cross-reactive to various degrees with the proteins in our library, which include two different cholera enterotoxins, two H-LTs, P-LT, and four chimeric proteins. Some of these reactions were blocked by GM1 ganglioside but not the oligosaccharide of GM1, a finding suggesting that the peptides generated antibodies to epitopes near, but not in, a GM1-binding domain. A hypothetical evolutionary tree based on the reported amino acid sequences of the various enterotoxins is constructed. As additional enterotoxins are described, it will be interesting to determine if and where they fit in this scheme.


Assuntos
Anticorpos Monoclonais/imunologia , Enterotoxinas/imunologia , Epitopos/análise , Proteínas de Escherichia coli , Escherichia coli/imunologia , Vibrio cholerae/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antibacterianos/imunologia , Especificidade de Anticorpos , Antígenos de Bactérias/imunologia , Toxinas Bacterianas/imunologia , Toxina da Cólera/imunologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Humanos , Dados de Sequência Molecular , Peptídeos/imunologia
18.
Rev Infect Dis ; 9(3): 544-61, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2440089

RESUMO

Hybridoma-derived monoclonal antibodies were raised to enterotoxins of the cholera family and to chimeric B-subunit proteins in which individual amino acid residues of a heat-labile, cholera-related enterotoxin from an Escherichia coli strain of porcine origin (P-LT) were substituted with corresponding residues from such an enterotoxin from an E. coli strain of human origin (H-LT). Single amino acid substitutions were found to have profound effects on the physicochemical behavior of the proteins and on their immunologic reactivity. With the use of enzyme-linked immunosorption assays (ELISAs) with and without the GM1 ganglioside receptor for these toxins, several distinct epitopes in GM1-binding domains were identified by different monoclonal antibodies. Polyclonal rabbit antisera to synthetic peptides of the cholera enterotoxin B subunit were cross-reactive to various degrees with the proteins in our library, which include two different cholera enterotoxins, two H-LTs, P-LT, and four chimeric proteins. Some of these reactions were blocked by GM1 ganglioside but not by the oligosaccharide of GM1, a finding suggesting that the peptides generated antibodies to epitopes near, but not in, a GM1-binding domain. A hypothetical evolutionary tree based on the reported amino acid sequences of the various enterotoxins is constructed. As additional enterotoxins are described, it will be interesting to determine if and where they fit in this scheme.


Assuntos
Toxinas Bacterianas/imunologia , Toxina da Cólera/imunologia , Enterotoxinas/imunologia , Epitopos/imunologia , Proteínas de Escherichia coli , Receptores de Superfície Celular , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Evolução Biológica , Toxina da Cólera/análise , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Escherichia coli , Gangliosídeo G(M1)/metabolismo , Receptores Imunológicos
19.
Dev Biol Stand ; 59: 51-62, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2408946

RESUMO

Single amino acid substitutions, introduced by genetic engineering, significantly modify the behavior of the B-subunits of the cholera/coli enterotoxin family in SDS-PAGE and also markedly affect the reactivity of the proteins with mouse hybridoma-derived monoclonal antibodies raised against H-LT. The results indicate that single amino acids play an important role in defining epitopes in these proteins.


Assuntos
Anticorpos Monoclonais/imunologia , Toxinas Bacterianas/imunologia , Toxina da Cólera/imunologia , Enterotoxinas/imunologia , Proteínas de Escherichia coli , Engenharia Genética , Sequência de Aminoácidos , Toxinas Bacterianas/análise , Toxina da Cólera/análise , Enterotoxinas/análise , Ensaio de Imunoadsorção Enzimática , Epitopos/análise
20.
Infect Immun ; 45(2): 518-21, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6378800

RESUMO

Heat-labile enterotoxins from Escherichia coli strains of porcine and human origin polymerize on heating to form high-molecular-weight aggregates, "procoligenoids," analogous to procholeragenoid derived from the cholera enterotoxin. This aggregation is accompanied by loss of biological activity (toxicity). Further heating results in the release of B-subunit oligomers, coligenoids, analogous to choleragenoid. Further studies are needed to determine whether, like procholeragenoid, the procoligenoids are superior antigens in stimulating gut immunity after parenteral administration.


Assuntos
Antígenos de Bactérias , Toxinas Bacterianas , Enterotoxinas , Proteínas de Escherichia coli , Escherichia coli/imunologia , Toxoides , Animais , Fenômenos Químicos , Química , Temperatura Alta , Humanos , Peso Molecular , Polímeros , Suínos/microbiologia
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