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H H Mollaret

Publications and source records attributed to H H Mollaret.

At least 19 recordsLinked to original sources
PubMed1999

[The discovery by Paul-Louis Simond of the role of the flea in the transmission of the plague].

After Yersin's two fundamental discoveries of the plague bacillus and of the rat's role in its propagation, no one had sought to solve the riddle of how the bacillus itself spread and how it contaminated man. P. L. Simond was the first to realise that manipulating a rat that had recently died could be extremely dangerous whereas after a time lapse of several hours the same dead rat presented no risks to man. He was also the first to detect an insect bite as being responsible for the lesions he had observed at the beginning of bubonic plague outbreaks and called "precocious plyctenas". After having verified the presence of the bacillus in fleas of dying rats, on 2 June 1898 Simond carried out his princeps experiment on the transmission of plague to rats by fleas. From then onwards, disinsectisation was added to deratisation in plague prophylaxis.

Animals↗
PubMed1998

[Tholozan and plague in Persia].

In Persia since 1858, Tholozan studied between 1870 and 1882 the plague foci of the iranian Kurdistan which shall be dealt a century later (1947-1963) with Dr. M. Baltazard and his co-workers from the Pasteur Institute of Teheran. Tholozan had already pointed out the localization of the disease in some well defined villages and gave a good clinical description mentioning the traces of flea bites on the patients skin. One knows nowadays that wild rodents (Meriones) are the storing places of the plague bacilli in the Kurdistan. Tholozan's observations confirmed by modern ones allow to consider him a great loïmologist of modern times.

Epidemiology↗
PubMed1995

[Concealing and denying the plague].

Some examples are given of plague epidemics which have been negated or dissimulated in order to avoid isolation and quarantine: epidemics of Marseille (1720), San Francisco (1900), Mauretania (1963-1967), Libya and Egypt (1984).

Disease Outbreaks↗
PubMed1993

Antibiotic treatment of Yersinia enterocolitica septicemia: a retrospective review of 43 cases.

Of 53 documented cases of Yersinia enterocolitica septicemia reported to the French national registry between 1985 and 1991, 43 files contained sufficient information on antibiotic treatment to be analyzed retrospectively. All patients had at least two positive cultures of blood collected before the initiation of treatment. All strains were susceptible in vitro to the antibiotics that are usually active against gram-negative rods except for older beta-lactam agents (i.e., aminopenicillins and first-generation cephalosporins). No multiresistant strain was isolated. Only four (7.5%) of the 53 patients died. Aminopenicillins, first-generation cephalosporins, and--when prescribed alone--amoxicillin/clavulanate were not effective. Third-generation cephalosporins, most often used in combination with other antibiotics, were successful in 85% of cases. Fluoroquinolones--alone or in combination--cured all of 15 infections, with patients improving rapidly and becoming apyretic within 1-4 days. These agents therefore seem to constitute the best treatment.

Adolescent↗
PubMed1990

Yersiniosis.

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Animals↗
PubMed1990

Comparison of restriction endonuclease analysis and phenotypic typing methods for differentiation of Yersinia enterocolitica isolates.

Restriction endonuclease analysis of chromosomal DNA (REAC) was used to study polymorphism in restriction fragment patterns among Yersinia enterocolitica isolates belonging to serogroups O3, O5,27, O8, O9, O13, and O21. Using the enzyme HaeIII and electrophoresis on thin (0.75-mm) vertical 5% polyacrylamide gels, we were able to distinguish at least 22 DNA fragment patterns among the 72 strains examined. The method showed the greatest discriminatory power with regard to serogroup O8, within which as many as 10 different DNA fragment patterns were detected among the 16 strains examined. Compared with O8, serogroups O3 and O9 were relatively homogeneous with regard to REAC patterns. The discriminatory power of the method was compared with H-antigen typing, biotyping, phage typing, antimicrobial susceptibility typing, and restriction enzyme analysis of the virulence plasmid (REAP), by means of Simpson's index of diversity. The results showed that REAC and REAP constitute an effective supplement or alternative to conventional phenotypic methods for tracing epidemiologically related isolates of Y. enterocolitica. Our finding that human and porcine isolates exhibited the same REAC, REAP, and H-antigen patterns provides additional support for the hypothesis that pigs play an important role in the epidemiology of human Y. enterocolitica infection.

Animals↗
PubMed1990

Yersinia enterocolitica tenosynovitis. The first case.

We describe a case of tenosynovitis of tibialis posterior due to Yersinia enterocolitica occurring after injury by a plant thorn in a 55-year-old man. The illness was chronic with 2 recurrences in spite of antibiotic treatment. Full recovery was obtained only after surgical intervention. Our patient's chronic course was fostered by the persistence of thorn fragments in the infected area and the exceptionally pathogenic character of the isolated colony of Yersinia.

Doxycycline↗
PubMed1989

Purification, location, and immunological characterization of the iron-regulated high-molecular-weight proteins of the highly pathogenic yersiniae.

We have previously shown that under iron limitation, different Yersinia species synthesize new polypeptides. Two of them, the high-molecular-weight proteins (HMWPs), are expressed only by the highly pathogenic strains. In the present study, the HMWPs from Y. enterocolitica serovar O:8 were purified by gel filtration, and specific antibodies were obtained. Using these antibodies, we show that the two polypeptides were synthesized de novo during iron starvation and that they were found essentially in the bacterial outer membrane fractions, although the majority of the molecules were not exposed on the cell surface. We also demonstrate that the two proteins had common epitopes and that the HMWPs of the high-virulence-phenotype species Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica serovar O:8 (a strain different from the one used to purify the proteins) are antigenically related. The less pathogenic and nonpathogenic strains did not exhibit cross-reacting material, suggesting that these strains do not synthesize even an altered form of the HMWPs.

Animals↗
PubMed1989

Clonal diversity and relationships among strains of Yersinia enterocolitica.

Allelic variation in the chromosomal genome of 81 isolates of Yersinia enterocolitica and single isolates of Yersinia intermedia, Yersinia frederiksenii, Yersinia mollaretii, and Yersinia kristensenii was assessed by analysis of electrophoretically demonstrable polymorphism in 21 genes encoding metabolic enzymes. Eighteen distinctive multilocus genotypes (electrophoretic types [ETs]) were identified. Clustering of the ETs from a matrix of pairwise genetic distances, based on the 21 enzyme loci, confirmed the genetic distinctness of serogroup 3 isolates of Y. intermedia, Y. frederiksenii, Y. mollaretii, and Y. kristensenii and identified another serogroup 3 isolate that was also not a member of Y. enterocolitica. The 13 ETs of Y. enterocolitica clustered into two groups: cluster A, which included eight ETs represented by isolates of serogroups 1; 2; 3; 5,27; and 9, and cluster B, which included four ETs represented by isolates of serogroups 8, 13, and 21. Clones of cluster A were found to be distributed worldwide, but those of cluster B were largely restricted to North America. Isolates of genotypes belonging to cluster B were lethal to mice, whereas those of cluster A were not, suggesting an influence of the chromosomal background on the virulence of Y. enterocolitica.

Alleles↗
PubMed1989

[Not Available].

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History, Modern 1601-↗
PubMed1988

In vitro expression of a 22-kilodalton Yersinia pestis polypeptide immunologically related to the 25-kilodalton plasmid-encoded protein of the three pathogenic Yersinia species.

Antibodies raised against the 25-kilodalton (p25) plasmid-encoded polypeptide of Yersinia enterocolitica recognized the homologous protein in the three Yersinia species grown in vitro. This polypeptide was recovered from whole cells as well as from the fluid supernatant of bacteria grown at 37 degrees C in a Ca2+-deficient medium. Furthermore, a 22-kilodalton (p22) plasmid-encoded polypeptide immunologically related to p25 was found only in Y. pestis during early growth. After 30 h of culture, the Y. pestis p25 and p22 were completely degraded, whereas the intensity of the Y. enterocolitica p25 was decreased, but the protein was still detectable in the fluid supernatant. This proteolytic activity was independent of the presence of the virulence plasmid. Some disulfide bonds are probably involved in the quaternary structure of the p25 of the three pathogenic species and of the Y. pestis p22.

Antibodies, Bacterial↗
PubMed1987

Expression of iron-regulated proteins in Yersinia species and their relation to virulence.

Under iron-starvation conditions, the different Yersinia species expressed various iron-regulated proteins. Among them, two high-molecular-weight outer membrane proteins were synthesized in high-virulence-phenotype Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica serovars O:8 and O:Tacoma but were present neither in low-virulence phenotype Y. enterocolitica serovars O:3 and O:9 nor in avirulent Y. frederiksenii, Y. kristensenii, Y. intermedia, and Y. enterocolitica serovar O:39. Thus, the degree of virulence correlates with the presence of the two high-molecular-weight proteins in Yersinia species.

Bacterial Outer Membrane Proteins↗