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1.
OBJECTIVE: The purpose of the study was to describe clinical and serologic features of Fisher syndrome associated with IgG anti-GQ1b ganglioside antibody following Campylobacter jejuni enteritis. DESIGN: A clinical trial. PARTICIPANTS: Four consecutive patients with Fisher syndrome were studied. INTERVENTION: Samples of sera from four patients were tested for reactivity to GQ1b ganglioside by enzyme-linked immunosorbent assay (ELISA). Campylobacter jejuni strains isolated from samples of stool from three patients were serotyped by the method of Penner and Hennessy and that of Lior. MAIN OUTCOME MEASURES: Serum IgG anti-GQ1b antibody titer and serotypes of C. jejuni. RESULTS: Diplopia occurred 8 to 14 days after the onset of diarrhea. Campylobacter jejuni was isolated from samples of stool from all of the patients. ELISA revealed a high serum IgG anti-GQ1b antibody titer for all four patients. Two patients had high serum titers of other antiganglioside antibodies frequently related to Guillain-Barré syndrome. These two patients developed limb weakness following the onset of ophthalmoplegia. The C. jejuni serotype was Penner's serotype 2 for all three of the patients tested. CONCLUSIONS: These findings suggest that C. jejuni, especially Penner's serotype 2, enteritis could trigger development of Fisher syndrome associated with IgG anti-GQ1b antibody.  相似文献   

2.
Campylobacter jejuni produces a toxin called cytolethal distending toxin (CDT). The genes encoding this toxin in C. jejuni 81-176 were cloned and sequenced. The nucleotide sequence of the genes revealed that there are three genes, cdtA, cdtB, and cdtC, encoding proteins with predicted sizes of 30,11-6, 28,989, and 21,157 Da, respectively. All three proteins were found to be related to the Escherichia coli CDT proteins, yet the amino acid sequences have diverged significantly. All three genes were required for toxic activity in a HeLa cell assay. HeLa cell assays of a variety of C. jejuni and C. coli strains suggested that most C. jejuni strains produce significantly higher CDT titers than do C. coli strains. Southern hybridization experiments demonstrated that the cdtB gene is present on a 6.0-kb ClaI fragment in all but one of the C. jejuni strains tested; the cdtB gene was on a 6.9-kb ClaI fragment in one strain. The C. jejuni 81-176 cdtB probe hybridized weakly to DNAs from C. coli strains. The C. jejuni 81-176 cdtB probe did not hybridize to DNAs from representative C. fetus, C. lari, C. "upsaliensis," and C. hyointestinalis strains, although the HeLa cell assay indicated that these strains make CDT. PCR experiments indicated the probable presence of cdtB sequences in all of these Campylobacter species.  相似文献   

3.
Three sets of primers were designed for PCR detection and differentiation of Campylobacter jejuni and Campylobacter coli. The first PCR assay was designed to coidentify C. jejuni and C. coli based on their 16S rRNA gene sequences. The second PCR assay, based on the hippuricase gene sequence, identified all tested reference strains of C. jejuni and also strains of that species which lack detectable hippuricase activity. The third PCR assay, based on the sequence of a cloned (putative) aspartokinase gene and the downstream open reading frame, identified all tested reference strains of C. coli. The assays will find immediate application in the rapid identification to species level of isolates. The assays combine with a protocol for purification of total DNA from fecal samples to allow reproducible PCR identification of campylobacters directly from stools. Of 20 clinical samples from which campylobacters had been cultured, we detected C. jejuni in 17, C. coli in 2, and coinfection of C. jejuni and Campylobacter hyointestinalis in 1. These results were concordant with culture and phenotypic identification to species level. Strain typing by PCR-restriction fragment length polymorphism of the flagellin (flaA) gene detected identical flaA types in fecal DNA and the corresponding campylobacter isolate. Twenty-five Campylobacter-negative stool samples gave no reaction with the PCR assays. These PCR assays can rapidly define the occurrence, species incidence, and flaA genotypes of enteropathogenic campylobacters.  相似文献   

4.
Campylobacter jejuni and Campylobacter coli are common causes of gastroenteritis in humans. Infection with C. jejuni or C. coli is commonly acquired by eating undercooked chicken. The goal of this study was to develop specific detection assays for C. jejuni and C. coli isolates based on the cadF virulence gene and its product. The cadF gene from C. jejuni and C. coli encodes a 37-kDa outer membrane protein that promotes the binding of these pathogens to intestinal epithelial cells. A fragment of approximately 400 bp was amplified from 38 of 40 (95%) C. jejuni isolates and 5 of 6 (83.3%) C. coli isolates with primers designed to amplify an internal fragment of the cadF gene. PCR was then used to amplify Campylobacter DNA from store-bought chickens. A 400-bp band was amplified from 26 of the 27 chicken carcasses tested by the PCR-based assay. The CadF protein was detected in every C. jejuni and C. coli isolate tested, as judged by immunoblot analysis with a rabbit anti-C. jejuni 37-kDa serum. In addition, methanol-fixed samples of whole-cell C. jejuni and C. coli were detected with the rabbit anti-37-kDa serum by using an indirect-immunofluorescence microscopy assay. These findings indicate that the cadF gene and its product are conserved among C. jejuni and C. coli isolates and that a PCR assay based on the cadF gene may be useful for the detection of Campylobacter organisms in food products.  相似文献   

5.
Campylobacter jejuni infection of mice initiated by intranasal administration was investigated as a potential model for studies of pathogenesis and immunity. By using a standard challenge (5 x 10(9) CFU), C. jejuni 81-176 was more virulent for BALB/c (72% mortality) than for C3H/Hej (50%), CBA/CAJ (30%), or C58/J (0%). Intranasal challenge of BALB/c was used to compare the relative virulence of three reference strains; C.jejuni 81-176 was more virulent (killing 83% of challenged mice) than C. jejuni HC (0%) or C. coli VC-167 (0%). The course of intranasally initiated C. jejuni 81-176 infection in BALB/c was determined. C. jejuni was recovered from the lungs, intestinal tract, liver, and spleen at 4 h after challenge, the first interval evaluated. After this initial interval, three distinct patterns of infection were recognized: (i) a progressive decline in number of C. jejuni CFU (stomach, blood, lungs), (ii) decline followed by a second peak in the number of organisms recovered at 2 or 3 days postchallenge (intestine, liver, mesenteric lymph nodes), and (iii) persistence of approximately the same number of C.jejuni CFU during the course of the experiment (spleen). Intranasally induced infection initiated with a sublethal number of bacteria or intranasal immunization with killed Campylobacter preparations resulted in both the generation of Campylobacter antigen-specific immune responses and an acquired resistance to homologous rechallenge. The model was used to evaluate the relative virulence of nine low-in vitro-passage (no more than five passages) isolates of C. jejuni species from patients with diarrhea. The patient isolates were differentially virulent for mice; one killed all exposed mice, three were avirulent (no deaths) and the remainder showed an intermediate virulence, killing 17 to 33%. Mouse virulence of Campylobacter strains showed a trend toward isolates originating from individuals with watery diarrhea; however, no association was found between mouse virulence and other signs or symptoms. There were no observed relationships between mouse virulence and bacterial Lior serotype or Fla polymorphic group. Intranasal challenge of BALB/c with C. jejuni is a useful model for the study of infection and vaccination-acquired immunity to this agent.  相似文献   

6.
Thirty Campylobacter jejuni (C. jejuni) strains isolated from stools of Israeli children with enteritis were tested for sensitivity to eight antimicrobial agents (MIC) and the presence of plasmids. It was found that all the isolates were sensitive to ciprofloxacin, ofloxacin, furazolidone and erythromycin. Of the 30 strains tested, 21 (70%) were found to be tetracycline-resistant, a relatively high resistance rate as compared with data from other countries and previous reports from Israel. Plasmids were detected in 17 out of 30 C. jejuni isolates (55.6%). A total of nine different plasmid profiles could be distinguished; six profiles were represented by one strain each. Of the 21 tetracycline-resistant strains, plasmids were found in 17 isolates (80%) carrying from 1-2 to 5 plasmids of various sizes. No plasmids were found in tetracycline-sensitive strains, with the exception of one isolate which contained a 24.4 MDa plasmid and was co-trimoxazole-resistant. Our studies indicate a relatively high percentage of tetracycline-resistant C. jejuni isolates in the Tel Aviv area. In 80% of these strains, various plasmid profiles were detected.  相似文献   

7.
Campylobacter jejuni is a major pathogen preceding Guillain-Barré syndrome (GBS), and most C. jejuni isolates from GBS patients belong to Penner serotype 19 (heat-stable; HS-19). We analyzed sixteen independent clinical isolates from GBS patients, twelve of which belonged to HS-19, three to HS-2, and one to HS-4, using PCR-based RFLP analysis of a flagellin-A (flaA) gene. Two isolates from patients with Miller Fisher syndrome (MFS), and 27 from patients with uncomplicated enteritis were also examined. All HS-19 isolates, regardless of GBS, showed an identical pattern (Cj-1) by RFLP typing and were distinguishable from those of the other Penner serogroups. In contrast, HS-2 and HS-4 isolates were divided into several different RFLP groups, suggesting HS-19 strains are genetically distinctive among C. jejuni isolates. A DNA fingerprinting method also failed to detect any specific band pattern for GBS-related C. jejuni isolates. We examined relationships among anti-GM1 antibody titres in the sera of GBS patients, clinical forms of GBS, serotype of C. jejuni, and the presence of GM1-like structures in lipopolysaccharide (LPS) components from C. jejuni isolates by immunoblotting. HS-19 related GBS was significantly associated with elevated anti-GM1 antibody titers in the sera of the patients, but not associated with any clinical pattern of GBS. No significant correlations were found between anti-GM1 antibody and the pattern of disease, or between GBS-related C. jejuni strains and the presence of GM1-like structures. HS-19 strains seem to be unique among C. jejuni isolates, and HS-19-related GBS may provide an excellent model for clarification of the pathogenesis of GBS.  相似文献   

8.
Poultry has long been cited as a reservoir for Campylobacter spp., and litter has been implicated as a vehicle in their transmission. Chicks were raised on litter removed from a broiler house positive for Campylobacter jejuni. Litter was removed from the house on days 0, 3, and 9 after birds were removed for slaughter. Chicks were raised on these three litters under controlled conditions in flocks of 25. None of these birds yielded C. jejuni in their cecal droppings through 7 weeks. Two successive flocks from the same Campylobacter-positive broiler house were monitored for Campylobacter colonization. Campylobacter jejuni prevalence rates were determined for each flock. Randomly amplified polymorphic DNA (RAPD)-PCR and 23S rRNA-PCR typing methods were used to group isolates. A high prevalence (60%) of C. jejuni in flock 1 coincided with the presence of an RAPD profile not appearing in flock 2, which had a lower rate of prevalence (28%). A 23S rRNA-PCR typing method was used to determine if strains with different RAPD profiles and different prevalence rates contained different 23S sequences. RAPD profiles detected with higher prevalence rates contained a spacer in the 23S rRNA region 100% of the time, while RAPD profiles found with lower prevalence rates contained an intervening sequence less than 2% of the time. Data suggest varying colonizing potentials of different RAPD profiles and a source other than previously used litter as a means of transmission of C. jejuni. These molecular typing methods demonstrate their usefulness, when used together, in this epidemiologic investigation.  相似文献   

9.
In the present study, 19 strains of Vibrio cholerae O1 biotype El Tor isolated during outbreaks of cholera in Guinea-Bissau in 1987, 1994, and 1995 were characterized to investigate a possible epidemiological relationship among the isolates. On the basis of ribotyping with the restriction enzyme BglI, 5 strains isolated in 1987 showed two closely related ribotypes, while 14 strains isolated in 1994 and 1995 showed the same ribotype that was distinct from the ribotypes of strains isolated in 1987. Southern blot hybridization of BglI-digested genomic DNA with a cholera toxin probe demonstrated that the strains isolated in 1987 showed an identical cholera toxin genotype, whereas O1 strains isolated in 1994 and 1995 showed the same genotype that was distinct from the genotype of strains isolated in 1987. These results were supported by the results of antibiotic susceptibility testing, in which strains isolated in 1987 showed resistance to polymyxin B only, while each of the strains from 1994 and 1995 showed resistance to polymyxin B, trimethoprim-sulfamethoxazole, and the vibriostatic agent O/129. Although our results are based on a limited number of V. cholerae O1 strains, they suggest that the epidemic in Guinea-Bissau in 1994 and 1995 was due to the introduction of a new strain to the country.  相似文献   

10.
Campylobacter jejuni strains are able to produce at least two different cytotoxins called "cytolethal distending toxin" (CLDT) and "cytolethal rounding toxin" (CLRT). In this study, we investigated the corresponding changes in CHO-K1 cells using the cell counter and analyzer system CASY 1. Determination of the cell volume after toxin treatment of the cells is a useful criterion for differentiation between the cytotoxic activities produced by Campylobacter strains. Incubation of the cells with crude CLDT resulted in a decrease in the cell count combined with a dramatic increase of the mean cell volume in comparison to the control culture. A decrease in the cell count was also seen as a response to CLRT preparations, while this toxin had no effect on the mean cell volume determined. It was shown that only CLDT caused histone-associated DNA fragments in the cytoplasm of CHO-K1 cells indicating an apoptotic pathway of cell death. In addition, the polymerase chain reaction (PCR) was employed to screen Campylobacter strains for the presence of the cdtB gene sequence, which was detectable in all strains investigated.  相似文献   

11.
BACKGROUND: Small intestine alterations produced by the enterotoxigenic capacity of Campylobacter jejuni subsp. jejuni are similar to the hydric, electrolytic and pathological changes caused by choleraic and thermolabile Escherichia coli toxins. AIM: To study the enterotoxigenic capacity of 4 strains of Campylobacter jejuni subsp. jejuni using the intestinal loop model. MATERIAL AND METHODS: Rat intestinal loops were inoculated with culture filtrates of the four strains. Enterotoxigenicity was assessed by fluid accumulation, the increase in Na+ and Cl- in the loop fluid, and cAMP increase in loop tissues. An enterotoxigenic Escherichia coil strain and sterile Brucella both were used as positive and negative controls, respectively. RESULTS: The filtrates of two strains produced fluid accumulation in the loops, significantly increased Na+ and Cl- secretion to the intestinal lumen and increased tissue cAMP levels. CONCLUSIONS: Some strains of Campylobacter jejuni subsp. jejuni are able to show enterotoxigenicity in vivo, increasing cAMP levels in the intestinal cells and altering electrolyte exchange mechanisms.  相似文献   

12.
64 sera of pigs and 22 sera of calves were investigated in a Helicobacter pylori-ELISA. The test system was validated with positive and negative reference sera. In contrast to other investigations it was tried to exclude false positive results by absorbing the sera with Wolinella succinogenes, Campylobacter jejuni subsp.jejuni, E. coli and Proteus mirabilis. This proved to be necessary, as the extinctions of some sera were reduced considerably. Using this technique sera of 5 pigs and 6 calves could be identified, which fulfilled the following criteria: 1. The extinctions were statistically significant above the mean value of the corresponding group after absorption with Campylobacter jejuni subsp.jejuni. 2. After absorbing the sera of pigs with 3 and the sera of calves with 4 bacteria the extinctions were above 50% of that of the human positive serum. 3. The extinctions of these sera were-like the positive reference sera-nearly not influenced by the absorption. These results indicate the presence of serum antibodies in pigs and calves, which react with epitops from Helicobacter pylori.  相似文献   

13.
The diarrheal response of orally inoculated infant mice to viable Vibrio cholerae and purified cholera toxin was quantitated by means of a fluid accumulation (FA) ratio. The FA ratio is defined as the gut weight/remaining body weight. FA ratios were determined in relation to time of exposure and dose. Onset of fluid accumulation with viable cells of strains CA401 and 569B occurred 8 h postinoculation and reached a near maximum of 16 h. A dose of 4 x 10(6) colony-forming units of strain CA401 was required for a positive response 16 to 18 h postinoculation. Several other classical cholera strains demonstrated a similar dose-related response. Strain 569B, however, required a 100-fold higher dose to give a positive response. Several mutant cholera strains were decreased virulence in other model systems elicited FA ratios decreased from wild-type values. Onset of fluid accumulation which cholera toxin occurred 6 to 8 h postinoculation and reached a maximum by 10 h. A dose of 0.5 microng was required for a positive response 10 to 12 h postinoculation. The positive response to toxin could be inhibited by preincubation with specific antitoxin.  相似文献   

14.
The present study determines the affinity of cholera toxin for the ganglioside series GM1, GM2, GM3, GD1A, GD1B, GT1B, asialo GM1, globotriosyl ceramide, and lactosyl ceramide using real time biospecific interaction analysis (surface plasmon resonance, SPR). SPR shows that cholera toxin preferably binds to gangliosides in the following sequence: GM1 > GM2 > GD1A > GM3 > GT1B > GD1B > asialo-GM1. The measured binding affinity of cholera toxin for the ganglioside sequence ranges from 4.61 x 10-12 M for GM1 to 1.88 x 10-10 M for asialo GM1. The picomolar values obtained by surface plasmon resonance are similar to Kd values determined with whole-cell binding assays. Both whole-cell assays and SPR measurements on synthetic membranes are higher than free solution measurements by several orders of magnitude. This difference may be caused by the effects of avidity and charged lipid head-groups, which may play a major role in the binding between cholera toxin, the receptor, and the membrane surface. The primary difference between free solution binding studies and surface plasmon resonance studies is that the latter technique is performed on surfaces resembling the cell membrane. Surface plasmon resonance has the further advantage of measuring apparent kinetic association and dissociation rates in real time, providing direct information about binding events at the membrane surface.  相似文献   

15.
16.
A new diagnostic procedure was developed to detect the flagellar antigen of Campylobacter jejuni and Campylobacter coli in canine faecal specimens and was tested on faecal samples from random-source dogs obtained from the local dog pound. Extraction of acid-soluble proteins was performed on faecal specimens and the extracted material was evaluated using species-specific monoclonal antibodies in an enzyme-linked immunosorbent assay. The assay detected all C. jejuni or C. coli infected specimens compared with direct selective faecal culture. One of 18 faecal specimens culture-negative for C. jejuni was identified as positive by the assay, i.e. a false positive rate of 1 of 18 (5.6%) and a corresponding specificity of 94.4%. These results suggest that the screening procedure developed to detect flagellar antigens of C. jejuni and C. coli in canine faecal samples should be further investigated as a diagnostic alternative to culture.  相似文献   

17.
Seven patients with Miller Fisher syndrome (MFS), six in the acute phase and one in the recovery phase, were investigated for serum antibodies against gangliosides and purified lipopolysaccharides (LPS) from different strains of Campylobacter jejuni, including the MFS-associated serotypes O:2 and O:23. Immunoglobulin G antibodies against gangliosides GT1a and GQ1b were found in five of six patients in the acute phase of disease. Three of these patients also displayed antibodies to ganglioside GD2, a finding not previously reported for MFS. All anti-GT1a- and anti-GQ1b-seropositive patients showed antibody binding to C. jejuni LPS, predominantly to O:2 and O:23 LPS. Antibody cross-reactivity between gangliosides GT1a and GQ1b and O:2 and O:23 LPS was demonstrated by adsorption studies. This cross-reactivity between gangliosides and C.jejuni LPS, which is obviously due to oligosaccharide homologies, may be an important pathogenetic factor in the development of MFS after C. jejuni infection.  相似文献   

18.
Campylobacter jejuni were isolated from 7 epidemic outbreaks (121 isolates), 15 patients with gastroenteritis, chicken meats (47 isolates) and chicken cecal contents (70 isolates). The isolates and one standard strain of C. jejuni JCM2013 were analysed by randomly amplified polymorphic DNA method (RAPD). Total of 254 C. jejuni isolates were divided 68 different RAPD types which included strains that did not to divided by Lior's or Penner's serotyping system. To compare the similarities of RAPD patterns among the isolates, the amplification patterns of DNA were estimated by means of the Dice coefficient, and clustering of strains was based on the unweighted average pair group method (UPGMA) to facilitate the plotting of a dendrogram. It suggests that amplification band patterns of human isolates were different from those of chicken ones. Thus additional information given from RAPD profiles serves for epidemiological investigation and RAPD analysis is recommended as rapid and effective typing method.  相似文献   

19.
Four Vibrio cholerae O139 Bengal strains isolated from surface water were characterized by antibiotic resistance, plasmid profile, presence of cholera toxin gene and random amplification of polymorphic DNA (RAPD) analysis. All four strains exhibit multiple resistance towards the antibiotics tested with a multiple antibiotic resistance index of 0.5-0.66, and harboured a 2.0 MDa non-conjugative plasmid. The Vibrio cholerae O139 Bengal were positive for the cholera toxin gene. Antibiotyping and random amplification of polymorphic DNA analysis with four primers proved to be useful in discriminating the isolates. RAPD proved to be more sensitive. These results reveal that there is significant genetic diversity among the Vibrio cholerae O139 Bengal strains studied.  相似文献   

20.
We determined the minimum inhibitory concentration (MIC) of DR-3355, a newly developed quinolone-derivative antibacterial agent, against clinical isolates of various bacterial species from enteritis patients, and compared them with those of ofloxacin (OFLX), ciprofloxacin (CPFX), nalidixic acid (NA), ampicillin (ABPC), kanamycin (KM). MIC90 of DR-3355 against 94 strains of Shigella spp. and 5 strains of Escherichia coli, 36 strains of Salmonella spp., 22 strains of Vibrio cholerae, 5 strains of Vibrio parahaemolyticus, and 19 strains of Campylobacter jejuni were 0.05, 0.10, 0.0025, 0.39, and 0.78 micrograms/ml, respectively. These values were 1/2 of that of OFLX, and two times of that of CPFX. MIC90 of DR-3355, OFLX and CPFX against C. jejuni were 0.78 micrograms/ml. MIC90 of DR-3355 against isolates from enteritis patients except for Vibrio spp., were 1/30 to 1/60 of those of NA, ABPC, and KM.  相似文献   

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