Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pneumococcal meningitis, because of their frequency and their severity, are regarded as an important problem of Public Health in Africa. In a great number of African countries, particularly Equatorial and Central Africa, the pneumococcus is the first agent of bacterial meningitis. The annual prevalence is estimated as about 14/100 000 persons. The case fatality rate (on 1 600 cases) is 49,5% ; the annual mortality reaches about 7/100 000 (28 000 annual deaths in Africa). The babies and the old persons are more exposed to the risk, with an annual prevalence of 28,5/100 000 before five years old, and of 16,1/100 000 after sixty years old. The risk is small between five and forty five years old. The risk is very high in patients homozygous for sickle-cell disease. The spread of all detected serotypes, by descending frequency is : 1, 5, 6, 3, 23, 12, 2, 14, 9, 18, 19, 4, 8, 29, 40, others (Danish system of nomenclature). The distribution according to age is indicated by the authors. A vaccine with only 8 serotypes (1, 5, 6, 3, 23, 12, 2, 14) could cover 80% of serotypes in Dakar. For the babies, addition to pneumococcal vaccine with polyribose phosphate of Haemophilus influenzae b, could be useful, because high prevalence of meningitis with this germ before five years old in Africa.
 ...
PMID:[Epidemiologic features of pneumococcal meningitis in Africa. Clinical and serotypical aspects (author's transl)]. 4 37

Serum samples were collected from 20 healthy White and 33 Black infants before and after immunisation with three doses of diphtheria-pertussis-tetanus vaccine and with one dose of Haemophilus influenzae type b polyribose phosphate vaccine and meningococcal group A and group C polysaccharide vaccines. Antibodies to these immunogens were measured and sera were allotyped for several Gm, A2m, and Km antigens. A highly significant association was found between the Km(1) allotype and the immune responses (difference between post-immunisation and pre-immunisation antibody levels) to H. influenzae and meningococcus C polysaccharides in the White children.
 ...
PMID:Association between immunoglobulin allotypes and immune responses to Haemophilus influenzae and Meningococcus polysaccharides. 8 9

In a first part of this report, purification and characterization of several nucleased from lysates of Haemophilus influenzae are described. The enzymes bind to DNA with agarose columns and are removed by elution with phosphate buffer. Among the considered enzymes, the exonucleases 1 and 3, and endonuclease, a DNA polymerase and a restriction enzyme were recovered mixed by raising the phosphate concentration from 0.1 to 0.3 M, while the ATP-dependent DNAase recovered well purified, by raising the phosphate concentration to 0.45 M. After a rechromatography, on a second DNA with agarose column, of the peak of the ATP-dependent DNAase, the specific activity tested with 3H-labeled DNA was 125 units/mg of protein, representing a 300-fold purification of the original crude extract. In a second part, we have investigated the inactivation, at various pH, of transforming DNA of Haemophilus influenzae wild strain Rd with the different eluted fractions of the column, in order to determine the importance of contamination with other enzymatic activities, and also in order to confirm the nature of theisolated enzymes with a biological method. Finally, with enzymatic extracts of mutant strain Rd com minus 56, a strain which integrates shorter than normal pieces of DNA and which is suspected to possess and "activated specific endonuclease" able to recognize even small conformational modifications in paired structures, we tried to detect this activity on artificially constructed heteroduplex regions in DNA.
 ...
PMID:Studies on deoxyribonucleases from Haemophilus influenzae on DNA agarose affinity chromatography. Two-step purification of ATP-dependent deoxyribonuclease. 23 41

Immunization with ribosomal preparations from Haemophilus influenzae type b elicited protective immunity in mice. Ribosomes from disrupted cells where isolated by differential centrifugation using sodium dodecyl sulfate. The washed ribosomes contained 25% protein and 75% ribonucleic acid and sedimented as a single peak on sucrose density gradient analysis with a sedimentation coefficient of 67S, using Escherichia coli ribosomes as a 70S marker. Immunodiffusion tests with antipolyribose phosphate serum showed that the ribosomes were free from capsular material. Mice immunized subcutaneously with ribosomes, with or without adjuvant, were challenged intraperitoneally with 100 to 1,000 mean lethal doses of H. influenzae type b suspended in gastric mucin. Significant protection was induced by ribosomes and was compared to that obtained after sublethal infection with live cells. The protection was greatly enhanced after incorporation of ribosomes into adjuvants. Maximum protection (90 to 95%) was observed at 1 to 2 weeks after immunization. Ribosomes from a nonencapsulated strain of H. influenzae were as immunogenic as those from the encapsulated strain, demonstrating that the capsular material is not responsible for immunogenicity of Haemophilus ribosomes.
 ...
PMID:Immunoprotective activity of ribosomes from Haemophilus influenzae. 30 Mar 60

The capsular polysaccharide (CP) of Haemophilus influenzae type b is known to be spontaneously released from the cells in culture. The CP is precipitable from culture supernatant by the cationic detergent hexadecyltrimethylammonium. Most of the nucleic acid and some of the protein, but almost none of the endotoxin, in the supernatant are co-precipitated. Extraction of the precipitate with progressively stronger NaCl solutions separates nucleic acid and protein from the CP and also effects a molecular size fractionation. Residual endotoxin and protein can be reduced by extraction with cold phenol and ultracentrifugation. The resulting preparation has ribose, ribitol, and phosphate as principal components and contains less than 1% other sugars, protein, or nucleic acid; it elutes on Sepharose 2B as a symmetrical peak with Kav 0.51.
 ...
PMID:Isolation of the capsular polysaccharide from culture supernatant of Haemophilus influenzae type b. 30 Mar 61

This investigation was designed to characterize the immunoprotective antigen of ribosomal preparations from Haemophilus influenzae. The ribosomes that elicited 80 to 90% protection contained 25% protein and 75% ribonucleic acid but did not contain any detectable hexoses. The immunodiffusion and hemagglutination inhibition tests also failed to demonstrate that the capsular material (polyribose phosphate) was in ribosomal preparations. Treatment of ribosomes with ribonuclease degraded 78% ribonucleic acid but did not affect the immunogenicity of such preparations. The proteolytic enzymes reduced the immunogenicity of ribosomes corresponding to the amount of protein degraded. The protection elicited by ribosomal protein extracted with 2-chloroethanol was comparable to that induced by intact ribosomes. In contrast, the low levels of protection observed by immunization with phenol-extracted ribonucleic acid were dependent on the amounts of contaminating protein. Finally, immunogenicity of ribosomal ribonucleic acid and protein was abrogated by treatment with proteolytic enzymes. These results clearly indicate that the protein associated with Haemophilus ribosomes is the major immunoprotective antigen.
 ...
PMID:Characterization of the immunoprotective antigen of ribosomal preparations from Haemophilus influenzae. 30 44

An endonuclease purified from Hemophilus influenzae made single strand breaks in DNA containing apurinic or apyrimidinic sites but had no detectable endonuclease activity on untreated native DNA. The new 5'-termini created at the cleavage sites were base-free deoxyribose 5-phosphate residues. The enzyme preparation also catalyzed the exonucleolytic release of 5'-mononucleotides from bihelical DNA and the hydrolysis of DNA 3'-terminal phosphomonoesters. The phosphatase-exonuclease activity was indistinguishable from that reported by Gunther and Goodgal (J. Biol. Chem. (1970) 245, 5341-5349) and resembled that of exonuclease III of Escherichia coli. The endonucleolytic and exonucleolytic activities could not be separated by electrophoresis, sedimentation, or gel filtration, and they were also affected simultaneously by mutation. The enzymatic activities appear to be functions of a single monomeric protein (M(r) = 30,000).
 ...
PMID:A DNase for apurinic/apyrimidinic sites associated with exonuclease III of Hemophilus influenzae. 30 19

Studies were conducted on the characterization of Haemophilus influenzae type b polysaccharide (HITB-PS) and its mitogenic activity upon peripheral lymphocytes. This capsular polysaccharide was found to contain hexosamines and hexoses in addition to the main components of ribose and ribitol phosphate. The molecular weight of HITB-PS was determined as 585,000. The affinity constant of HITB-PS to unfractionated lymphocytes was 3.13 X 10(3) M-1 with 1.11 X 10(4) binding sites per cell. HITB-PS was found to be mitogenic for both human T and B lymphocytes. At optimum doses, a three to five fold increase in 3H-thymidine incorporation into T and B cells was observed. Higher than optimum doses resulted in suppression of this mitogenicity. The effect of concanavalin A (Con A) mitogenicity was detected in T and B cells treated with effective as well as suppressive doses of HITB-PS; the mitogenic activities of Con A and HITB-PS were found to be independent of each other.
 ...
PMID:Characterization and mitogenic activity of Haemophilus influenzae type B capsular polysaccharide. 30 27

An enzyme-linked immunosorbent assay was developed to detect the presence of the ribose-ribitol phosphate capsular antigen of Haemophilus influenzae type b in laboratory and clinical specimens. The assay is simple, sensitive, specific, and quantitative and should prove to be of value in the diagnosis and management of H. influenzae infections.
 ...
PMID:Enzyme-linked immunosorbent assay for detection and quantitation of capsular antigen of Haemophilus influenzae type b. 31 Apr 25

Lipopolysaccharide from strains of Haemophilus influenzae was extracted and isolated by the hot phenol-water procedure. The preparations were relatively insoluble in water but could be solubilized with surface-active agents. The preparations contained carbohydrate (30%), fatty acid (29%), and phosphate (4.7%); protein content was less than 1%. Thin-layer chromatography, gas-liquid chromatography, and colorimetric assays detected glucose, galactose, glucosamine, heptose, and a 2-keto-3-deoxy-octonate-like molecule (less than 1%). Neither methylpentose nor dideoxyhexose was detected. The lipid portion was composed of fatty acids common to lipopolysaccharide of Salmonella. The preparations provoked positive dermal Shwartzman reactions and biphasic febrile responses in rabbits, responses typical of endotoxic activity. The 50% lethal dose for mice was decreased from 16.5 microgram/g to 0.015 microgram/g by concomitant administration of actinomycin D. The preparations were shown to be polyclonal activators of bone marrow-derived (B) cells. Limulus lysate gelation was seen with 8.0 ng of lipopolysaccharide. Preliminary hemagglutination data suggested at least three different antigenic factors associated with the lipopolysaccharide of H. influenzae type b. The H. influenzae lipopolysaccharide appeared biologically similar to that of enterobacteria but chemically different.
 ...
PMID:Characterization of lipopolysaccharide of Haemophilus influenzae. 31 Aug 55


1 2 3 4 5 6 7 8 9 10 Next >>