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J Heesemann

Publications and source records attributed to J Heesemann.

229 records · Page 13Linked to original sources

[Imported mussels as a cause of Vibrio parahaemolyticus gastroenteritis].

Two strains of Vibrio parahaemolyticus were isolated from stool specimens of a patient who came down with gastroenteritis 20 hours after eating imported mussels which had not been cooked sufficiently. This is the first documented case of V. parahaemolyticus enteritis acquired in the Federal Republic of Germany.

Adult↗

Persistence of Yersinia enterocolitica in man.

Ten patients with chronic Yersinia enterocolitica infections are described. The initial diagnosis was made by culture, significant agglutinin titres and indirect immunofluorescence (IF) on biopsies. During the chronic phase, culture and agglutinin titres were negative, but specific serum IgA and IgG antibodies reactive with at least two, i.e. the 36 kDa and the 46 kDa, virulence-associated released proteins were demonstrated in nine patients by immunoblot techniques. One patient had only IgG antibodies. The chronically elevated IgA production was the result of chronic stimulation of the gut-associated lymphoid tissue by virulent persistent Yersinia antigen, which was identified by IF with O-specific antiserum and monospecific antiserum to the 46 kDa released protein in biopsies. Virulent Yersinia bacilli were demonstrated in the intestinal mucosa and in the lymphoid tissue of the submucosa associated with macrophages in patients with chronic ileitis and arthritis, in granulomatous centres of lymph nodes in patients with chronic lymphadenopathy and in portal infiltrates in a patient with chronic hepatitis. Recognition of persistent Yersinia infections may have therapeutic implications.

Agglutination Tests↗

Possible reasons for failure of conventional tests for diagnosis of fatal congenital toxoplasmosis: report of a case diagnosed by PCR and immunoblot.

Diagnosis of subclinical congenital toxoplasmosis has to rely on serological methods or isolation of the parasite. We present a case of congenital toxoplasmosis, in which conventional tests failed to establish the diagnosis. It was shown that this infant developed an intrathecal antibody response that was directed only against one of two Toxoplasma gondii strains used for routine diagnosis. In contrast to conventional tests, the diagnosis of cerebral toxoplasmosis could be established by using immunoblot and polymerase chain reaction (PCR). We therefore suggest that in unclarified cases, PCR and immunoblot, using at least two different strains of T. gondii, should be considered as additional tools for diagnosis of an infection with Toxoplasma and that examination of cerebrospinal fluid may be critical.

Adult↗

Influence of antibiotics on IgA and IgG response and persistence of Yersinia enterocolitica in patients with Yersinia-associated spondylarthropathy.

The IgA and IgG antibody response to plasmid-encoded outer membrane proteins was studied in 59 patients with yersinia-associated spondylarthropathy during 15 months of follow-up. Initially, all patients had specific IgA and IgG antibodies to the 36 and 46 kDa and 30% also to the 26 and 58 kDa released proteins, which correlated with the finding of virulent Yersinia bacilli in intestinal biopsies. IgA disappeared in 69% of untreated patients after nine months and persisted in 31% after one year. IgA disappeared within three to six months in 81% of the patients treated with antibiotics for four to six weeks and persisted in 6% after one year (p less than 0.002). IgG antibodies to the 36 and 46 kDa outer membrane proteins persisted in 80% of all patients. Disappearance of IgA was coupled with disappearance of yersinia from intestinal biopsies.

Adult↗

Phylogeny and dating of some pathogenic keratinophilic fungi using small subunit ribosomal RNA.

The phylogenetic relationship of representative members of the genera Trichophyton, Microsporum and Epidermophyton was studied. 844 base pairs were compared after sequencing the nuclear 18S ribosomal RNA gene spanning the most variable area within the central 600 bases of this gene. The dermatophytes, which are monophyletic in origin, could be classified most effectively when placed as a subgroup in the Onygenales, Ascomycotina. The calculated radiation time was about 50 million years ago. The early cenozoic adaptive explosion of mammals, which can serve as a host for the keratinophilic fungi, provides corroboration for proximate co-evolution.

Arthrodermataceae↗

The tranquilizing injection of Yersinia proteins: a pathogen's strategy to resist host defense.

Pathogenic bacteria of the genus Yersinia possess a type III secretion apparatus by which they can inject up to six effector proteins into host cells. These so-called effector Yops (Yersinia outer proteins) disrupt cellular immune defense functions such as TNF-alpha release, O2-production or phagocytosis and thereby allow Yersinia to grow extracellularly. Recent findings indicate that the effector Yops are highly active proteins that engage in crucial eukaryotic signaling mechanisms. For instance, the translocated tyrosine phosphatase YopH dephosphorylates the focal adhesion proteins paxillin and p130Cas within target cells. Furthermore, the Yersinia effector YopP is able to induce apoptosis in macrophages presumably by blocking MAP kinase and NFKB mediated signaling events. Here we discuss recent advances concerning the intracellular targets and biochemical signaling mechanisms regulated by the translocated Yersinia effectors.

Animals↗

[Diagnostic and prognostic significance of serologic studies in Yersinia arthritis].

Commonly-used serological methods for the determination of Yersinia antibodies are based on the presence of agglutinins, which are frequently absent or of low titer when arthritis begins. Stool cultures are usually negative at that time, so many Yersinia infections are underdiagnosed. On the other hand, significant agglutinin titers, of diagnostic value, become frequently minimised because of cross reactivity with Yersinia and other gram-negative bacteria. With the immunoblot-technique, using specific virulence-associated antigens and the detection of class-specific antibodies, clear statements are possible about whether there is a recent or an old Yersinia infection. As Yersinia arthritis may have an acute start and a protracted course over months, an exact diagnosis is essential for therapy and prognosis, as well as for answering the question of whether there is acute exacerbation of a preexisting rheumatoid illness of an additional infectious arthritis.

Adolescent↗

The established Yersinia pestis biovars are characterized by typical patterns of I-CeuI restriction fragment length polymorphism.

The genomes of three main biovars of Yersinia pestis were subjected to restriction fragment length polymorphism analysis using I-CeuI endonuclease. I-CeuI which is encoded by a mobile intron in Chlamydomonas engamenans recognizes a 25-bp site in the ribosomal RNA rrl gene and cuts DNA of most representatives of Enterobacteriaceae into seven fragments corresponding to the presence of seven rrn-operons. Glycerol-positive Y. pestis strains (biovars antiqua and mediaevalis) contain seven ribosomal operons which can be recognized by I-CeuI endonuclease. However, glycerol-negative strains of Y. pestis biovar orientalis expose only six restriction sites for I-CeuI. The restriction fragment length polymorphism patterns obtained with I-CeuI make it possible to distinguish between three biovars of Y. pestis. Use of another rare cutting restriction enzyme, Bln/I, permits differentiation between pigment-adsorbing and avirulent non-pigment-adsorbing Y. pestis. Still, due to homologous recombination between the two copies of IS 100 insertion sequence bracketing the pgm-locus, the mechanism of deletions in the pgm-locus seems to be confined only to strains of biovars antiqua and mediaevalis, and can be different in Y. pestis strains of biovar orientalis. The I-CeuI restriction patterns of two Yersinia strains isolated within a ten-year period in the port of St. Petersburg and originally identified as Y. pseudotuberculosis 01 turned out to be related to typical representatives of Y. pestis biovar antiqua. These strains could be exported from the same source or circulate among Rattus norvegicus population of the port as non-pigment-adsorbing avirulent immunogenic clone.

Animals↗

[Reactive arthritis associated bacteria as the etiology of undifferentiated oligoarthritis].

Undifferentiated oligoarthritis (UOA) resembles clinically reactive arthritis (ReA), but does not fulfill the diagnostic criteria. In 46 patients with UOA, in 16 with ReA, and in 15 with rheumatoid arthritis (RA) the humoral and cellular immune response to the ReA-associated bacteria Chlamydia trachomatis, Yersinia enterocolitica, Shigella flexneri, Salmonella enteritidis, Campylobacter jejuni and Borrelia burgdorferi was investigated in paired samples of synovial fluid and peripheral blood. An antigen-specific lymphocyte proliferation in SF was found in 75% of the ReA and in 39% of UOA patients, but in none with RA. Shigella and Chlamydia in ReA and Yersinia and Chlamydia in UOA were the most frequent stimulating antigens. There was a poor correlation between antigen specific lymphocyte proliferation and specific antibodies. We conclude that these bacteria might have a pathogenetic role, not only in ReA, but also in UOA.

Adult↗

[Synovial cellular immune response to bacterial pathogens in patients with chronic juvenile arthritis].

Juvenile chronic arthritis is a heterogenous disease with an ill-defined pathogenesis. In our study, synovial fluid (SF) and peripheral blood (PB) of 70 children with oligoarthritis were investigated; bacteria-specific lymphocyte proliferation and antibodies to arthritogenic bacteria were determined. Specific cellular immune responses in SF but not in PB were found in 4/7 patients with either Lyme- or reactive arthritis (60%). In comparison, in subgroup JCA II (n = 45) encompassing mainly elder HLA B27 positive boys, a specific response in SF but again not in PB was detected in 10 children to Yersinia enterocolitica (YE), in four children either to Borrelia burgdorferi (BB) and Chlamydia trachomatis (CT), and in one child to Campylobacter jejuni (CJ). In contrast, in subgroup JCA I (n = 17) encompassing mainly young ANA-positive girls with chronic iridocyclitis, no specific response was found. The correlation of the synovial cellular and the humoral immune responses was 100% in the case of BB and 50% for YE; no antibodies against CT or CJ were detectable. Neither specific cellular nor humoral immune responses were detected against Salmonella or Shigella. We conclude that, in the pathogenesis of some patients with JCA, bacterial microbes have a triggering role. Mainly YE, but also BB and CT are responsible for cases of JCA in which no symptomatic infection preceded.

Adolescent↗

Prevalence of enteropathogenic bacteria in surgically treated chronic inflammatory bowel disease.

BACKGROUND/AIMS: In order to assess the potential impact of bacterial eradication on recurrence rates, the prevalence of various enteropathogenic bacteria and toxins in chronic inflammatory bowel diseases (CIBD) was prospectively examined. METHODOLOGY: Stool, sera and gut tissue samples from a total of 59 patients (33 males, 26 females; mean age: 42 years +/- 14; 21 Crohn's disease, 14 ulcerative colitis, 24 controls) were examined for the presence of enteropathogenic bacteria by culture, immunoblotting and PCR. RESULTS: Conventional cultures failed to detect obligate pathogenic bacteria. By PCR, mycobacteria were found in 85% of all groups, with mycobacterium paratuberculosis not detected. Yersinia species were observed in 63% of patients with Crohn's disease, in 46% of patients with ulcerative colitis, and in 36% of the control patients. Pathogenic E. coli were identified in stool samples of three patients with ulcerative colitis (21%) by amplifying the EAE-gene, one of whom exhibited shiga-like-toxin as well. CONCLUSIONS: We concluded that mycobacteria do not play a causative role in CIBD. Yersinia species seem to persist in intestinal tissue in CIBD patients without adequate immune response and might, thus, contribute to tissue destruction. E. coli infections contribute to the disease process in a small group of patients with ulcerative colitis and their eradication might eliminate the need for immediate surgical intervention.

Adult↗