Search PubMed⌕ Search

Biomedical subjects

J C Feeley

Publications and source records attributed to J C Feeley.

At least 127 records · Page 7Linked to original sources
PubMed1970

Titration of cholera antitoxin in human sera by microhemagglutination with formalinized erythrocytes.

Microtiter hemagglutination tests employing formalinized sheep erythrocytes sensitized with either crude or purified cholera toxin were used to assay the cholera antitoxin content of human sera. Comparable results were obtained with either crude or purified toxin-sensitized cells with the exception of two sera that gave unusually high hemagglutination titers with the crude toxin. Sera from 13 convalescent cholera patients showed a high degree of correlation between antitoxin levels as determined in vitro by the hemagglutination test and in vivo by the skin permeability factor neutralization test. Fourfold or greater rises in antitoxin levels between acute and convalescent sera were detected in 9 of 15 patients with bacteriologically proven cholera. No significant increases in titer were observed in 14 cases of noncholera diarrhea. Cholera antitoxin was detected by hemagglutination in only 1 of 33 sera, obtained from eight countries, containing vibriocidal antibodies. Formalinized sheep erythrocytes sensitized with toxin and stored at 4 C in the presence of 1:10,000 thimerosal were stable and sensitive for at least 6 months (the longest time tested).

Animals↗
PubMed1970

Isolation of Vi Antigen from Escherichia coli by a New Method.

Vi antigen was isolated from a trichloroacetic acid-deproteinized saline extract of acetone-killed and -dried cells of Escherichia coli (5396/38) by ethyl alcohol precipitation and absorption on diethylaminoethyl-Sephadex. Stepwise elution with distilled water, 0.15 m NaCl, and 0.5 m NaCl resulted in recovery of Vi antigen and two additional antigenic fractions (designated antigens 1 and 2). Vi antigen was an acidic polymer which flocculated readily with albumin, contained 6.0% nitrogen, and had a sedimentation coefficient of 14.7S. Vi was shown to be antigenic in the rabbit by the indirect hemagglutination test and in mice by tests for protection against challenge with Salmonella typhosa, wherein it was more protective by the intraperitoneal (ip) than by the subcutaneous (sc) route. Vi antigen prepared by this method was much more protective for mice than was the Vi antigen used in previous studies. The other antigens, not fully characterized, were also capable of protecting mice. Antigen 1 was more effective by the sc than the ip route, whereas antigen 2 was more effective by the ip route. The relationship between Vi antigen and antigens 1 and 2, as demonstrated by hemagglutination tests with rabbit antisera, remains unclear.

Journal Article↗
PubMed1970

Biochemistry of Vibrio cholerae Virulence I. Purification and Biochemical Properties of PF/Cholera Enterotoxin.

A simple method for concentrating, isolating, and purifying PF/cholera enterotoxin from culture supernatant fluids is presented. Precipitation with dextran sulfate and ammonium sulfate, followed by gel filtration and ion-exchange chromatography, yielded PF/enterotoxin of high biological potency. Although not completely free from traces of vibriocidal antibody-stimulating activity, the resultant purified toxic immunogen appeared homogeneous as judged by immunoelectrophoresis, immunodiffusion, and disc electrophoresis. Advantages and disadvantages of this purification method are discussed in comparison with those of previously published techniques.

Journal Article↗
PubMed1970

Effect of formalin treatment on electrophoretic mobility of cholera toxin.

Crude cholera toxin detoxified by treatment with Formalin showed an increased mobility and a decrease in the number of detectable protein constituents when compared with the parent toxin by disc electrophoresis. The significance of these observations in relation to the enhanced antigenic activity of cholera toxoid as compared to parent toxin is discussed.

Journal Article↗
PubMed1969

Immunological response of the rabbit to Vi antigen.

Vi antibody response of rabbits varied depending on whether Vi antigen was administered in particulate or soluble state. Vi antigen in particulate form induced hemagglutinins, bacterial agglutinins, and passive cutaneous anaphylaxis (PCA) antibodies, whereas soluble Vi antigen induced only hemagglutinins. Guinea pigs passively sensitized with antisera against particulate Vi antigen gave PCA reactions when challenged with either soluble or cellular Vi antigen; antisera against soluble Vi antigen were negative for PCA. The specificity of PCA was demonstrated by its dependence on the Vi concentration and by absorption of PCA activity from antisera with V-form cells of Salmonella typhosa.

Agglutination Tests↗
PubMed1969

Immunological response of three mouse strains to typhoid vaccine and Vi antigen.

Vi-agglutinin, active cutaneous anaphylaxis and protective responses (ed(50)) of three mouse strains (CFW, NIH, and Balb/cAnN) to acetone-inactivated typhoid vaccine and soluble Vi antigen were compared. Seven days after immunization with either typhoid vaccine or Vi antigen the three strains of mice differed with respect to Vi-antibody titers. Significant differences were observed in the protective responses. Each mouse strain was significantly better protected by the intraperitoneal than by subcutaneous route of immunization. Active cutaneous anaphylaxis was more pronounced in showing strain differences in response to Vi antigen. The serological responses to Vi antigen of the strains of mice did not correlate with their protective response.

Agglutination Tests↗
PubMed1969

Somatic O antigen relationship of Brucella and Vibrio cholerae.

The antigenic relationship between Brucella species and Vibrio cholerae was examined by agglutinin and agglutinin-absorption tests by using rabbit antisera. Brucella antisera agglutinated only the Inaba serotype of V. cholerae and at low titer. Inaba-reactive antibody was absorbed by either heat-stable (100 C, 2 hr) Ogawa or Inaba O antigens. Cholera antisera from rabbits immunized with either O or HO antigens of either Ogawa or Inaba serotypes contained brucella agglutinins. This activity was absorbed completely from Ogawa antisera by either Ogawa or Inaba O antigens but only partially from Inaba antisera by Ogawa O antigen. These findings support the claim of Gallut that the cross-reaction is due to heat-stable O antigens of V. cholerae rather than heat-labile flagellar antigens as described in many text books. The cross-reactive component is more dominant in the Inaba than in the Ogawa serotype of V. cholerae.

Agglutination↗
PubMed1969

Report of the 1966-67 cholera vaccine field trial in rural East Pakistan. I. Study design and results of the first year of observation.

A controlled cholera vaccine field trial was carried out in rural East Pakistan during the 1966-67 cholera season. A commercial cholera vaccine of average potency was tested in 40 000 children aged 3 months to 14 years in 1- and 2-dose schedules. In the cholera season extending for 8 months following immunization, a single dose produced an over-all protection of 46%; 2 doses at an interval of 1 month provided 64% protection. The single dose was virtually ineffective in children under 5 years, but provided significant protection in older children. The enhanced effect of the 2-dose schedule was primarily due to the boosting of protection in children under the age of 5 years. The duration of significant protection, even with the 2-dose schedule, did not appear to extend beyond the first 3 months of the 8-month cholera season.

Adolescent↗
PubMed1968

Site and characteristics of electrolyte loss and effect of intraluminal glucose in experimental canine cholera.

The site and characteristics of gastrointestinal electrolyte loss were investigated in eight dogs with experimental cholera induced by orogastric administration of 6-hr broth cultures of Vibrio cholerae, strain Ogawa 395. In these animals, all electrolyte losses originated in the small bowel, predominantly from the jejunum and ileum. The bicarbonate concentration of the small bowel fluid showed a progressive increase from duodenum, where it was less than that of plasma, to the terminal ileum, where it was significantly greater than that of simultaneously obtained plasma. Studies of the responses of chronic Thiry-Vella jejunal loops (five dogs) and chronic Thiry-Vella ileal loops (five dogs) to intraluminal challenge by cholera exotoxin demonstrated that all loops exhibited isotonic electrolyte loss for a 14-18 hr period after challenge. The bicarbonate concentration of fluid produced by exotoxin-challenged jejunal loops was not significantly different from that of plasma, whereas the ileal loops produced fluid with a bicarbonate concentration approximately three times that of plasma. The effect of intraluminal glucose on the response of canine gut to cholera exotoxin was investigated by perfusion studies in 12 dogs with chronic Thiry-Vella fistulae. Intraluminal glucose significantly enhanced isotonic fluid absorption in both jejunal and ileal loops. The net effects of glucose on isotonic fluid absorption were equal before and after intraluminal administration of crude cholera exotoxin. These data suggest that cholera exotoxin causes gut electrolyte loss by a mechanism independent of that by which glucose enhances sodium absorption.

Animals↗