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1.
The cellular fatty acid composition of 41 strains of suspected Campylobacter jejuni, 23 from human cases of gastroenteritis and 18 from animals, was examined by gas-liquid chromatography. Three of the 23 human isolates and 2 of 18 animal isolates did not contain 19:0 cyclopropane fatty acid and were identified as C. laridis. The remaining 36 strains had cellular fatty acid profiles consistent with C. jejuni but could be divided into three groups on the ratio of the concentration of 18:1 and 19:0 cycloproprane. Most human isolates (85%) were in groups II or III whereas most animal isolates (56%) were in group I. It is proposed that gas-liquid chromatographic analysis of cellular fatty acids is a relatively easy method for epidemiological typing of C. jejuni isolates.  相似文献   

2.
The cellular fatty acid composition of 41 strains of suspected Campylobacter jejuni, 23 from human cases of gastroenteritis and 18 from animals, was examined by gas-liquid chromatography. Three of the 23 human isolates and 2 of 18 animal isolates did not contain 19:0 cyclopropane fatty acid and were identified as C. laridis. The remaining 36 strains had cellular fatty acid profiles consistent with C. jejuni but could be divided into three groups on the ratio of the concentration of 18:1 and 19:0 cycloproprane. Most human isolates (85%) were in groups II or III whereas most animal isolates (56%) were in group I. It is proposed that gas-liquid chromatographic analysis of cellular fatty acids is a relatively easy method for epidemiological typing of C. jejuni isolates.  相似文献   

3.
During 2008 and 2009, within the framework of the Hungarian monitoring program of antibiotic resistance of zoonotic agents from food-producing animals, a significant number (43 strains) of Campylobacter lanienae were detected for the first time in Hungary. The isolates were genotyped using partial 16S rRNA gene sequencing and pulsed-field gel electrophoresis using three different restriction enzymes. The antimicrobial resistance of the isolates was determined by microtiter broth dilution. C. lanienae isolation was successful only from swine but not from other animal species. According to phylogenetic analysis, clustering of the isolates shows the same extensive genetic diversity as other Campylobacter species. Sequence analysis of the partial 16S rRNA gene showed that additional variations exist in variable regions Vc2 and Vc6. SmaI restriction enzyme proved to be the most efficient for pulsed-field gel electrophoresis analysis of C. lanienae. A significant tetracycline resistance (60.9%) and the presence of erythromycin-, enrofloxacin-, and multiresistant C. lanienae strains were found. Although the pathogenic potential of C. lanienae in humans is currently unknown, this study demonstrates that C. lanieanae is common in pigs in the country, provides further details on the genotypic and phenotypic properties of C. lanienae, and offers a genotyping method for use in source tracing.  相似文献   

4.
Human campylobacteriosis is currently the most common cause of acute bacterial gastroenteritis on the island of Ireland, accounting for over 3,000 laboratory reports per year, where circa 2,000 reports originate from the Republic of Ireland and circa 1,000 reports from Northern Ireland. Elsewhere, consumption of contaminated poultry has been associated with the zoonotic transmission of disease, therefore it was the aim of this study to examine the phenotypic and genotypic relatedness of campylobacters isolated from chickens and humans locally. Sixty isolates were subtyped using phenotyping techniques (biotyping, phage-typing), as well as genotyping techniques (multilocus enzyme electrophoresis (MEE), ribotyping) and the data compared. The frequency of shared phenotypes and genotypes between poultry and humans varied depending on the typing technique employed ranging from 98.2% of human isolates sharing a similar resistotyping (MAST) disc type with poultry strains to 20% similarity with MEE typing. Overall, this small study is the first report on phenotypic and genotypic relatedness between human and poultry campylobacters in Northern Ireland, isolated under controlled conditions. The study demonstrated an association between chicken and human sub-species types, taken from a relatively contained epidemiological environment. Further work is required with larger numbers of isolates coupled with typing schemes, which are able to reliably cluster strains from chicken and humans, which share high degrees of clonality, before local poultry can be conclusively proven to be a significant source of human campylobacteriosis.  相似文献   

5.
Ribotyping was used to study the epidemiology of Aeromonasassociated gastro-enteritis in young children. Ribotyping patterns of 29 Aeromonasstrains (16 Aeromonas caviae, 8 Aeromonas hydrophila, 3 Aeromonas eucrenophila, 1 Aeromonas veronii, and 1 Aeromonas encheleia) isolated from primary stool cultures of sick children were compared using the GelCompare software with patterns of 104 strains (39 Aeromonas eucrenophila, 29 Aeromonas caviae, 11 Aeromonas encheleia, 10 Aeromonas hydrophila, 6 Aeromonas bestiarum, 3 Aeromonas veronii, 3 Aeromonas popoffiiand 3 Aeromonas media) isolated from their household environment in order to investigate the route of transmission of these bacteria. Fifteen strains (47%) isolated from stool cultures of patients showed the same riboprofile as strains found in contacts or environment. In particular, three strains isolated from patients shared the same riboprofile with strains found in their domestic environment. The wide diffusion of potentially pathogenic Aeromonasstrains in our household samples, and the high rate of asymptomatic carriers among family members, suggested that predisposing factors of the host could make children prone to an Aeromonas-related intestinal disease.  相似文献   

6.
Salmonella enterica serovar Heidelberg has been recognized as one of the most common serovar associated with foodborne infections in the United States. It is also frequently isolated from nonhuman sources and has increasingly shown resistance to various antimicrobial agents. The present study was undertaken to identify the predominant antimicrobial resistance phenotypes and genotypes of Salmonella Heidelberg (n = 95) isolates of human, swine, and turkey origin. Antimicrobial susceptibility was done using Kirby-Bauer disk diffusion method with a panel of 12 antimicrobials. Pulsed-field gel electrophoresis genotyping was used to determine the diversity of the isolates. The antimicrobial resistance genes and carriage of Class 1 and 2 integrons were determined by polymerase chain reaction. All Salmonella Heidelberg isolates from swine were resistant to one or more of the antimicrobials tested and the majority (73.3%) showed multidrug resistance to streptomycin, tetracycline, and kanamycin (R-type: StTeKm). About 80% of the Salmonella Heidelberg isolates of human origin were pan-susceptible, however, one isolate showed multidrug resistance to 10 of 12 antimicrobials tested. Among the multidrug-resistant (MDR) Salmonella Heidelberg isolates, Class 1 integrons with variable sizes of 1.2 to 1.5 kb were detected in six isolates (three each) from humans and swine. DNA sequencing revealed that Class 1 integrons of both human and swine origin carried a gene encoding aminoglycoside adenyltransferase (aadA). Resistance genes identified in other loci include aphA1-Iab, strA, bla(TEM), and tetA (B). Both human and swine MDR strains of Salmonella Heidelberg carried the resistance phenotypes on self-transferable plasmids. Dendrogram analysis of pulsotypes indicated possible clonality of Salmonella Heidelberg between isolates of human and swine origin. The findings in this study indicate the increasing significance of swine as reservoirs of emerging MDR serovars, such as MDR Salmonella Heidelberg, is of public health significance.  相似文献   

7.
Brucella isolated in humans and animals in Latin America from 1968 to 2006   总被引:1,自引:0,他引:1  
We report a retrospective analysis of 1933 Brucella strains isolated from humans and animals in Latin American countries between 1968 and 1991 and in Argentina between 1994 and 2006. During the first period 50% of strains were from humans, mainly from Argentina, Mexico and Peru but, while B. suis was the main cause of infection in Argentina, B. melitensis was responsible for most infections in the other countries. In Argentina in the later years, B. melitensis and B. suis were observed more frequently than in the first period while isolation of B. abortus decreased. Of 145 B. melitensis human isolates, eight gave susceptibility patterns to dyes and penicillin and two were B. melitensis biovar 3, which has never been reported in animals. Forty-six percent of B. suis isolated were resistant to dyes which is an atypical feature in this species.  相似文献   

8.
Sixty-six broiler flocks were sampled to determine the presence of Campylobacter spp. at slaughter in 1998. Thirty flocks (45%) tested positive and C. jejuni was identified in all isolates. Combined pulsed-field gel electrophoresis/amplified fragment length polymorphism (PFGE/AFLP) subtyping of 177 isolates from 24 positive flocks revealed 62 subtypes; 16 flocks harboured more than one subtype. When subtyping 101 clinical C. jejuni isolates collected in the same time period and area, 60 PFGE/AFLP types were identified. Comparison of subtypes from poultry and human isolates revealed three shared PFGE/AFLP types, which were present in 11 human isolates. Fifty per cent of all poultry isolates and 39% of all human isolates were resistant to ciprofloxacin. The present study confirms the increase in ciprofloxacin resistance in both human and poultry C. jejuni isolates in Austria, as observed in several countries worldwide. A small number of human isolates shared PFGE/AFLP types with poultry isolates, however, further studies should also focus on the identification of other sources of C. jejuni infection in humans.  相似文献   

9.
Sixty-one isolates of Aeromonas spp. from the faeces of pigs, cows and a variety of associated environmental sources were examined for the characteristics that are reputed to have roles in pathogenicity. Most isolates of Aeromonas hydrophila were cytotoxic (96.4%) and were capable of producing cell elongation factor (75%) and haemagglutinins (67.9%). In contrast few of the Aeromonas caviae isolates produced these three markers (13.6%, 27.3% and 36.4% respectively). In general, Aeromonas sobria occupied an intermediate position (36.4%, 27.3% and 54.5%), but they did produce the highest mean invasion index for HEp-2 cells. Statistical analysis revealed significant associations between the carriage of these factors and it was clear that many isolates of aeromonads from water and animals possessed the full battery of putative virulence factors.  相似文献   

10.
Consumption of poultry is considered to be an important source of human infection with Campylobacter. In the period from 2008 to 2010, 50 isolates of Campylobacter jejuni from human faeces were analysed and compared with 61 isolates from poultry by pulsed field gel electrophoresis using SmaI and KpnI. Based on the analysis of SmaI macrorestriction profiles, 86 isolates (77.5?%) were assigned to 15?S clusters: 31 (62?%) from humans and 55 from poultry (90.2?%). Altogether 21 isolates (19?%) exhibited macrorestriction profiles common to both humans and poultry after restriction with SmaI and KpnI. A total of five identical pulsotypes were isolated from both poultry and patients and one of them appeared in eight different locations in the time interval of one year. These results indicate that poultry could be an important source of Campylobacter infection in Split and Dalmatia County which is the biggest County in Croatia and the most important tourist destination.  相似文献   

11.
12.
Long-term prospective studies in monkeys have shown that vasectomy is associated with an increase in atherosclerotic disease. The purpose of the present investigation is to evaluate whether vasectomy in men is associated with atherosclerotic disease in the coronary arteries. In this study information was obtained on the vasectomy status in a series of 7,420 men who had previously been referred for coronary angiography because of cardiovascular symptomatology and have been followed for as long as 9 years to evaluate coronary artery bypass surgery and the natural history of the disease. It was found that 5.0% had a vasectomy prior to angiography. Two different data analysis procedures were used to determine whether the vasectomized men had a greater degree of angiographically determined coronary occlusive disease than the nonvasectomized men. Subgroups with minimal and extensive coronary artery disease were also analyzed. Results of all analyses show that the vasectomized men did not have more coronary occlusive disease. Possible patient selection biases in this study are discussed.  相似文献   

13.
A total of 89760 human and 22551 non-human isolates of salmonella were serotyped in Canada during the period 1983-92. There were 2180 reported outbreaks associated with 10065 cases during the 10-year period. The most common salmonella serovars isolated from human and non-human sources were S. typhimurium and S. hadar. The third and fourth most common serovars from human sources were S. enteritidis and S. heidelberg, respectively, and from non-human sources they were S. heidelberg and S. infantis. The number of S. typhimurium isolations from human and non-human sources showed a downward trend over the 10-year period. A total of 222 outbreaks of S. typhimurium associated with 1622 cases occurred. The S. hadar isolations from human and non-human sources reached a peak during the years 1987-90 and declined thereafter. The number of human isolates of S. enteritidis increased until 1985 and fluctuated at a level of 8.3-12.8% of all human isolates thereafter. Seventy-three outbreaks of S. enteritidis infection associated with 568 cases occurred. More than 50% of the S. enteritidis infections in humans were caused by phage type (PT) 8. During the review period, infections caused by PT4 were less common and were almost exclusively found in people who had travelled abroad. The annual isolation rates of S. heidelberg from human and non-human sources increased steadily during the period. Bacteriophage typing of serovars from outbreaks showed that contaminated food products of poultry and bovine origin were common sources of human infection. Salmonella typhi was identified as the cause of 43 small outbreaks affecting 116 persons.  相似文献   

14.
15.
A study was carried out with four healthy young adult men, consuming a self-selected diet, to investigate quantitative aspects of the gastrointestinal absorption, urinary excretion, and body retention of egg selenium in comparison with selenite. The approach involved simultaneous consumption of egg biologically labeled (intrinsic) with the stable isotope 74Se and a dose of selenite labeled with 76Se (extrinsic label). Four labeled test diets, given on days 6, 16, 26, and 36 of the study were employed, each differing in their protein source: test diet I, 74Se-labeled egg white; diet II, 74Se-labeled egg yolk (high labeling dose) plus balanced L-amino acid mixture; diet III, 74Se-labeled egg yolk (low labeling dose) plus balanced amino acid mixture; and diet IV, balanced amino acid mixture extrinsically labeled with both 74SeO32- and 76SeO32-. The latter diet was included to assess the magnitude of any cross-isotope methodological bias. Fractional absorption (means +/- SEM) for Diet IV was 0.771 +/- 0.010 for the 74SeO32- and 0.656 +/- 0.021 for the 76SeO32- (ratio: 0.851 +/- 0.020); reflecting a small overall cross-isotope bias. Accepting the measurements made with 74SeO32- as the more accurate, experimentally determined values of absorption for the extrinsic tag were adjusted accordingly. The corrected absorption for these diets (% of dose) was (mean +/- SEM; first value for intrinsic label, second value for extrinsic label): diet I, 54.1 +/- 0.7 and 55.4 +/- 2.2; diet II, 76.7 +/- 0.8 and 83.0 +/- 1.8; diet III, 79.0 +/- 1.5 and 85.2 +/- 4.0.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
17.
18.
This study was conducted to examine the in vitro activity of antimicrobials against Campylobacter spp. isolates from chicken and human sources and the genetic interrelation among them. During 2004-2008, a total of 173 Campylobacter spp. isolated from chicken meats (60 domestic and 62 imported chicken meats) and humans (n?=?51) were tested for susceptibility to nine antimicrobials. Of 173 isolates, 140 (80.9%) showed multidrug resistance (MDR) against three to eight antimicrobials. The most frequent pattern type was MDR to four antimicrobials: ciprofloxacin, nalidixic acid, ampicillin, and tetracycline. Over 52.6% (91/173) of the isolates tested were resistant to these four antibiotics simultaneously. Especially, two and five isolates originated from Korea and Brazil showed resistance against all antibiotics tested, except for florfenicol. Further, 95% (57/60) of the isolates originated from domestic chicken showed resistance to ciprofloxacin, the antimicrobial agent of choice for treatment of human campylobacteriosis. Genotypic characterization of all Campylobacter isolates performed by pulsed-field gel electrophoresis yielded 74 types among the 173 isolates. Isolates sharing the same or similar genetic clusters were detected in different countries at different times. The pulsed-field gel electrophoresis patterns of chicken-related isolates were closely related to those of isolates from humans with gastroenteritidis. The results of this study suggest that MDR Campylobacter spp. are widespread and that Campylobacter with similar genotypes are circulating both in humans and in chicken meat in Korea.  相似文献   

19.
The aim of this study was to investigate the prevalence and mechanism of quinolone resistance among selected nontyphoid Salmonella (NTS) isolates. A total of 1279 NTS isolated from food animals (n=692) and humans (n=587) between 1995 and 2009 were investigated by serotyping, antimicrobial susceptibility testing, screening for plasmid-mediated quinolone resistance (PMQR) genes qnr, aac(6')-Ib-cr, and qepA and mutations in the quinolone resistance-determining region (QRDR) of gyrA and parC by PCR, and DNA sequencing. Three hundred thirty (47.7%) of 692 animal isolates and 177 (30.2%) of 587 human isolates were resistant to nalidixic acid. Most animal (94.8%, 313/330) and human (99.4%, 176/177) NTS exhibited decreased ciprofloxacin susceptibility (minimum inhibitory concentration [MIC]: 0.125-2?mg/L). None of them carried qnr or qepA gene. However, aac(6')-Ib was identified in six animal isolates, of which four carried aac(6')-Ib-cr gene. Based on antimicrobial resistance profile, year of isolation, MIC for quinolones and fluoroquinolones, and isolation frequency of serotype, 114 animal and 83 human isolates were tested for QRDR mutations. All contained a single mutation within the QRDR of gyrA at either codon 87 or 83, and 41 of them contained an additional mutation in parC. The most prevalent mutation was Asp87-Tyr (n=107), followed by Asp87-Gly (n=28), Asp87-Asn (n=26), Ser83-Tyr (n=22), and Ser83-Phe (n=14). Point mutations in parC were observed outside the QRDR, which included 40 isolates with Thr57-Ser substitution and 1 Salmonella Typhimurium with a novel Glu51-Lys substitution. In conclusion, a point mutation within the QRDR of gyrA was primarily responsible for quinolone resistance and reduced susceptibility to fluoroquinolones in NTS in Korea. To our knowledge, this is the first report of occurrence of aac(6')-Ib-cr gene among NTS in Korea. The spread of NTS carrying aac(6')-Ib-cr is of serious concern and should be carefully monitored.  相似文献   

20.
Blastocystis is a common enteric protist colonizing probably more than 1 billion people along with a large variety of non-human hosts. This protist has been linked to symptoms and diseases such as abdominal pain, constipation, diarrhea, flatulence and irritable bowel syndrome (IBS). Remarkable genetic diversity has been observed, leading to the subdivision of the genus into multiple subtypes (ST), some of which are exclusively found in non-human hosts. The aim of this study was to determine the distribution of Blastocystis STs in different Colombian hosts. We obtained fecal samples positive for Blastocystis by microscopy from 277 humans, 52 birds, and 117 mammals (25 cattle, 40 opossums, 40 dogs, 10 rats and 2 howler monkeys). The samples were submitted to DNA extraction, PCR and sequencing using primers targeting the small subunit rRNA gene, and ST identification was performed according to DNA barcoding. We observed the occurrence of ST1 (34%) and ST2 (23%) and lower proportions of STs 3 (11.4%), 4 (0.8%), 6 (19.8%) and 8 (10.5%). Domesticated mammals shared the same STs as those usually seen in humans (ST1, ST2, ST3), while birds and marsupials had STs, which are usually rare in humans (ST6, ST8). Further studies implementing high-resolution molecular markers are necessary to understand the phylodynamics of Blastocystis transmission and the role of this stramenopile in health and disease in Colombian populations, and to expand on the phylogeographic differences observed so far with a view to exploring and understanding host–parasite co-evolution.  相似文献   

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