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PubMed2006

Atypical pathogens as etiologic agents in hospitalized patients with community-acquired pneumonia in Korea: a prospective multi-center study.

Local epidemiologic data on the etiologies of patients hospitalized with community-acquired pneumonia (CAP) is needed to develop guidelines for clinical practice. This study was conducted prospectively to determine the proportion of atypical bacterial pathogens in adults patients hospitalized with CAP in Korea between October 2001 and December 2002. Microbiological diagnosis was determined by serology for antibodies to Mycoplasma pneumoniae, Chlamydia pneumoniae, and Legionella pneumophila. Nucleic acid of M. pneumoniae and C. pneumoniae in respiratory samples and Legionella antigen in urine samples were detected. The study population consisted of 126 patients (71 males, 55 females), averaging 54.6 yr (SD+/-17.8), whose paired sera were available. An etiologic diagnosis for atypical pathogens was made in 18 patients (14.3%): C. pneumoniae 9 (7.1%), M. pneumoniae 8 (6.3%), and L. pneumophila 3 patients (2.4%). Streptococcus preumoniae and other typical pathogens were isolated from 36 patients (28.6%). Of 126 patients, 16 (12.7%) were admitted to intensive care unit and atypical pathogens were identified in 5 patients (31.3%). Initial clinical features of patients with pneumonia due to atypical, typical or undetermined pathogens were indistinguishable. We conclude that atypical pathogens should be seriously considered in hospitalized patients with CAP, when initiating empiric treatment in Korea.

Adult↗
PubMed1993

[Proteinase activity in the isolates of Trichomonas vaginalis according to their pathogenicity].

Ten axenic isolates of Trichomonas vaginalis were subcutaneously injected to the BALB/c mice in order to assess their pathogenicity by means of so-called "mouse assay" method. All the isolates revealed neutral and acid proteinase activities both in their lysates and in culture media, but the specific activities of both proteinases in the severely pathogenic group were significantly higher than the mildly pathogenic group (p < 0.05). In the SDS-PAGE system in which the electrophoretic gels contained 0.4% gelatin as the substrate, five different banding patterns of trichomonal proteinases were detected, and the patterns were closely related with the pathogenicity of the isolates of T. vaginalis. All five bands might be regarded as cysteine proteinases group in the inhibitor assays. The cytotoxicity of the lysates of T. vaginalis to the target Chinese hamster ovarian (CHO) cell line was also significantly different according to the pathogenicity of the isolates, and generally lower in the lysates treated with cysteine proteinase inhibitors than in the control lysates. In summarizing the results, it might be considered that the proteinases of T. vaginalis showing five electrophoretic banding patterns are closely related with the pathogenicity and cytotoxicity of the isolates of T. vaginalis.

Adult↗
PubMed1993

[Natural killer cell activity in mice infected with free-living amoeba with reference to their pathogenicity].

The purpose of this observation was to investigate the natural killer cell activities in mice infected with pathogenic free-living amoeba, Naegleria fowleri and Acanthamoeba culbertsoni according to the infection doses, and infected with non-pathogenic free-living amoeba, Naegleria gruberi. The natural killer cell activity was examined by means of target binding capacity, active NK cell and maximum recycling capacity of the mice after inoculating free-living amoebae with low and high doses. The mice infected with 1,103, 1,105 A. culbertsoni trophozoites showed mortality rates of 6.9% and 65.5%, respectively. The mice infected with 1,104, 1,105 N. fowleri trophozoites showed mortality rates of 5.9% and 72.2%, respectively. The NK cell activities in all experimental groups increased significantly on day 1 after infection as compared with control group, and then remarkably declined thereafter, there was no difference of the cytotoxic activity of the NK cells in mice among inoculation doses of pathogenic free-living amoebae. The target binding capacities of NK cells and percentages of activated NK cells in mice infected with pathogenic free-living amoebae were significantly increased a day after infection, as compared with control group. There was no difference of the maximal recycling capacities of NK cells in all experimental groups as compared with control group. There was significant difference in the cytotoxic activity and single cell cytotoxicity of NK cells between the experimental groups infected with pathogenic free-living amoebae and that infected with non-pathogenic free-living amoebae.

Acanthamoeba↗
PubMed1997

[cDNAs encoding the antigenic proteins in pathogenic strain of Entamoeba histolytica].

The differential display reverse transcription polymerase chain reaction (DDRT-PCR) analysis was performed to identify the pathogenic strain specific amplicons. mRNAs were purified from the trophozoites of the pathogenic strain YS-27 and the non-pathogenic strain S 16, respectively. Three kinds of first stranded cDNAs were reverse transcribed from the mRNAs by one base anchored oligo-dT11M (M: A, C, or G) primers. Each cDNA template was used for DDRT-PCR analysis. A total of 144 pathogenic strain specific amplicons was observed in DDRT-PCR analysis using primer combinations of the 11 arbitrary primers and the 3 one base anchored oligo-dT11M primers. Of these, 31 amplicons were verified as the amplicons amplified only from the mRNAs of the pathogenic strain by DNA slot blot hybridization. Further characterization of the 31 pathogenic strain specific amplicons by DNA slot blot hybridization analysis using biotin labeled probes of the PCR amplified DNA of cysteine proteinase genes revealed that 21 of them were amplified from the mRNAs of the cysteine proteinase genes. Four randomly selected amplicons out of the rest 10 amplicons were used for screening of cDNA library followed by immunoscreening and all of them were turned out to be amplified from the mRNA.

Animals↗
PubMed1993

Application of the polymerase chain reaction to the epidemiology of pathogenic and nonpathogenic Entamoeba histolytica.

We used the polymerase chain reaction (PCR) to study the epidemiology of pathogenic and nonpathogenic Entamoeba histolytica in a rural community in Mexico. Formalin-fixed stool samples were used for extraction of DNA. The PCR amplifications were performed using two sets of primers that discriminate between pathogenic or non-pathogenic E. histolytica. A total of 201 randomly selected individuals were studied. Among them, 25 (12%) were diagnosed to be infected with E. histolytica by microscopy; PCR identified 24 of these as positive (sensitivity = 0.96) and of 176 negative individuals, only three were identified as positive (specificity = 0.98). The PCR analysis defined three populations: 14 cases were positive for both pathogenic and nonpathogenic E. histolytica, nine cases were positive for pathogenic and negative for nonpathogenic E. histolytica, and only one case was negative for pathogenic and positive for nonpathogenic E. histolytica. Infection by E. histolytica was strongly associated to infection with Entamoeba coli (odds ratio [OR] = 9.41, 95% confidence interval [CI] = 3.09, 28.65, P < 0.0004) and Endolimax nana (OR = 6.15, 95% CI = 2.03, 18.17, P < 0.0004). This new technique has high specificity and sensitivity; it is simple, reproducible, fast, avoids the need to culture trophozoites, and can be applied in the field for epidemiologic studies.

Adolescent↗
PubMed2004

Prevalence of pathogenic Escherichia coli and parasites in infants with diarrhoea in Kumasi, Ghana.

OBJECTIVES: To determine the relative frequencies and prevalence rates of pathogenic Escherichia coli and intestinal parasites in hospitalised infants (0-5 years) in Kumasi. DESIGN: A prospective descriptive study of screening 162 (83 males and 79 females) infants with diarrhoea and 122(64 males and 58 females) non-diarrhoeal infants controls for pathogens (E. coli and intestinal parasites) by standard microbiological methods. SETTING: Komfo Anokye Teaching Hospital and Maternal and Child Hospital, Kumasi, Ghana. RESULTS: From the 162 in the diarrhoeal group 96(59.6%) pathogens, and from the 122 in the control group, eight (6.6%) pathogens were isolated. Enteropathogenic E. coli (EPEC) was the most frequently detected pathogen, accounting for 24(14.8%) of the findings in the diarrhoeal group, five (4.1%) in the non-diarrhoeal control group. Of the 26 EPEC isolates, there were nine serotypes with the three dominant ones being 0125 (6), 0119 (5), and 026 (15). Other agents isolated included Ascaris lumbricoides 18(11.1%) and two (1.6%), Cryptosporidium 13(8.0%) and one (0.8%) for diarrhoeal and non-diarrhoeal infants respectively. The following were detected only in diarrhoeal stools. Giardia lamblia, six (3.7%); Trichomonas hominis, three (1.9%); Trichuris trichiura one (0.6%) and hookworm, one (0.6%). CONCLUSION: From this study, EPEC and Cryptosporidium may be considered as important diarrhoeagenic pathogens and it is hoped that provision of potable water and good sanitation may decrease diarrhoeas in infants caused by these agents.

Case-Control Studies↗
PubMed2002

Density of total and pathogenic (tdh+) Vibrio parahaemolyticus in Atlantic and Gulf coast molluscan shellfish at harvest.

The densities of total and pathogenic Vibrio parahaemolyticus in 671 samples of molluscan shellfish harvested in 1999 and 2000 from 14 sites in seven Gulf and Atlantic coast states were determined at 2-week intervals over a period of 12 to 16 months in each state. Changes in V. parahaemolyticus densities in shellfish between harvest and sample analysis were minimized with time and temperature controls. Densities were measured by direct plating techniques, and gene probes were used for identification. Total and pathogenic V. parahaemolyticus organisms were identified with probes for the thermolabile direct hemolysin (tlh) gene and the thermostable direct hemolysin (tdh) gene, respectively. An enrichment procedure involving 25 g of shellfish was also used for the recovery of pathogenic V. parahaemolyticus. The densities of V. parahaemolyticus in shellfish from all harvest sites were positively correlated with water temperature. Shellfish from the Gulf Coast typically had higher densities of V. parahaemolyticus than did shellfish harvested from the North Atlantic or mid-Atlantic coast. Vibrio parahaemolyticus counts exceeded 1,000 CFU/g for only 5% of all samples. Pathogenic (tdh+) V. parahaemolyticus was detected in approximately 6% of all samples by both procedures, and 61.5% of populations in the positive samples from the direct plating procedure were at the lower limit of detection (10 CFU/g). The frequency of detection of pathogenic V. parahaemolyticus was significantly related to water temperature and to the density of total V. parahaemolyticus. The failure to detect pathogenic V. parahaemolyticus in shellfish more frequently was attributed to the low numbers and uneven distribution of the organism.

Animals↗
PubMed2003

Evaluation of a select strain of Lactobacillus delbrueckii subsp. lactis as a biological control agent for pathogens on fresh-cut vegetables stored at 7 degrees C.

Raw vegetables inoculated with selected pathogenic bacteria were treated with a strain of Lactobacillus delbrueckii subsp. lactis, which was selected for its ability to produce hydrogen peroxide at refrigerated temperatures. The vegetables inoculated included broccoli, cabbage, carrots, and lettuce. Each vegetable was rinsed, chopped, and stored under conditions similar to those used for ready-to-eat vegetables sold at retail. Portions of each vegetable were separately inoculated with one of two pathogenic bacteria, Escherichia coli O157:H7 or Listeria monocytogenes. Prior to packaging, one portion of each inoculated vegetable was treated with a cell suspension of the selected strain of L. delbrueckii subsp. lactis. The vegetables were stored at 7 degrees C for 6 days. The populations of pathogens and lactobacilli on each sample were enumerated on storage days 0, 3, and 6. Although populations of L. delbrueckii subsp. lactis remained at high levels during storage, there was no noticeable antagonistic action against the pathogens under conditions similar to those used for these products at the retail level. Each pathogen survived on all vegetables throughout storage. Further testing revealed that there was apparently sufficient catalase activity in the cut vegetables to destroy enough of the hydrogen peroxide to prevent antagonistic action against the pathogens.

Colony Count, Microbial↗
PubMed2004

Internalization of bacterial pathogens in tomatoes and their control by selected chemicals.

The effect of different washing or sanitizing agents was compared for preventing or reducing surface and internal contamination of tomatoes by Salmonella Typhimurium and Escherichia coli O157:H7. The tomatoes were inoculated by dipping them in a bacterial suspension containing approximately 6.0 log CFU/ml of each pathogen and then rinsing them with tap water, hypochlorite solution (250 mg/liter), or lactic acid solution (2%, wt/vol). All treatments were applied by dipping or spraying, and solutions were applied at 5, 25, 35, and 55 degrees C. With the exception of the lactic acid dip at 5 degrees C, all treatments reduced both pathogens on the surfaces of the tomatoes by at least 2.9 cycles. No significantly different results were obtained (P > 0.05) with the dipping and spraying techniques. For internalized pathogens, the mean counts for tomatoes treated with water alone or with chlorine ranged from 0.8 to 2.1 log CFU/g. In contrast, after lactic acid spray treatment, all core samples of tomatoes tested negative for Salmonella Typhimurium and, except for one sample with a low but detectable count, all samples tested negative for E. coli O157:H7 with a plate count method. When the absence of pathogens was verified by an enrichment method, Salmonella was not recovered from any samples, whereas two of four samples tested positive for E. coli O157:H7 even though the counts were negative. Few cells of internalized pathogens were able to survive in the center of the tomato during storage at room temperature (25 to 28 degrees C). The average superficial pH of tomatoes treated with tap water, chlorine, or lactic acid was 4.9 to 5.2, 4.1 to 4.3, and 2.5, respectively (P < 0.05), whereas no differences were observed in the internal pH (3.6 to 3.7) of the tomatoes treated with different sanitizers. The general practice in the tomato industry is to wash the tomatoes in chlorinated water. However, chlorine is rapidly degraded by organic matter usually present in produce. Therefore, lactic acid sprays may be a more effective alternative for decontaminating tomato surfaces. The use of warm (55 degrees C) sprays could reduce pathogen internalization during washing.

Colony Count, Microbial↗
PubMed1999

Enteric pathogens in southern Indian HIV-infected patients with & without diarrhoea.

This study was undertaken to determine the carriage rate of various enteric pathogens in southern Indian patients with HIV infection, both with and without diarrhoea. Stool from 111 consecutive HIV-positive patients (50 without and 61 with diarrhoea) was examined by microscopy and culture. Jejunal biopsy and fluid examination were carried out if diarrhoea persisted, with negative stool examination. Enteric pathogens were detected from stool in 57.4 per cent of diarrhoeal patients compared to 40 per cent of those without diarrhoea (P > 0.05). Jejunal biopsy and fluid examination provided 11 additional diagnoses. Protozoa accounted for 71.8 per cent of all pathogens isolated. Isospora was significantly more common in patients with (11/61) than in those without (2/50) diarrhoea (P < 0.05). Bacterial pathogens were isolated more commonly from patients with diarrhoea (12/61 compared to 2/50, P < 0.05). Isolation rate of pathogens was higher from patients with diarrhoea for more than 2 wk, compared to those with less than 2 wk duration. Remission of diarrhoea either spontaneously or with symptomatic therapy was observed in 22 patients with acute diarrhoea. A high enteric carriage of a number of pathogens was noted in HIV patients without diarrhoea, but I. belli and bacterial enteropathogens were more likely to be associated with diarrhoea.

Adult↗
PubMed1998

Comparison of immunological and molecular methods for the diagnosis of infections with pathogenic Sarcocystis species in sheep.

Sheep may be infected by four species of Sarcocystis: Sarcocystis tenella and Sarcocystis arieticanis are pathogenic, Sarcocystis gigantea and Sarcocystis medusiformis are non-pathogenic. The two pathogenic species may cause abortion or acute disease during the early phase of infection and chronic disease during the late phase of infection. Thus far, diagnosis of sarcocystiosis has been limited, because traditional diagnostic tests based on the detection of Sarcocystis-specific antibodies are only genus-specific and, thus, cannot differentiate between pathogenic and non-pathogenic Sarcocystis species. In addition, most of these tests can only detect chronic sarcocystiosis. Therefore, diagnosis of acute sarcocystiosis or Sarcocystis-induced abortion has been based mainly on post-mortem examination, i. e. after the animal had succumbed to the disease. Recently, we have established species-specific PCR assays based on unique ribosomal RNA gene sequences of S. tenella and S. arieticanis. These assays enable the diagnosis and differentiation of infections with S. tenella and S. arieticanis in sheep intra vitam during the acute phase of the disease and, therefore, facilitate for the first time comprehensive studies on the epidemiology and importance of infections with pathogenic Sarcocystis species in sheep.

Animals↗
PubMed2002

[Factors of Yersinia pestis providing circulation and persistence of plague pathogen in ecosystems of natural foci. Communication 2].

To maintain continuous circulation of plague pathogen in natural foci, the pathogen should be capable of invading host organism, resisting the bactericide protective systems of rodent, and reproducing itself to maintain the content of bacteria at a level sufficient for further transmission by fleas to a new host. Each of these stages of the Yersinia pestis circulation is determined by a variety of factors of plague pathogen, which may act either individually or in combination. Each of the factors itself may be involved in the pathological process at different stages of its development or in pathogen transmission. However, it is only the aggregate of the factors (regardless of significant or insignificant individual contribution to the sum effect) that provides persistence of plague pathogen in natural foci. The plague pathogen factors providing its transmission from one host organism to the next as well as correlation of individual factors of pathogensis and expression of various household genes with plague pathogensis virulence are considered in the second communication. This review was compiled on the basis of not only well-known works but also some sources of limited availability, particularly, for English-speaking audience.

Animals↗
PubMed2004

The pathogenicity and antibiotic resistance of coagulase-negative Staphylococci isolated from the maxillary and ethmoid sinuses.

AIM OF THE STUDY: To investigate the pathogenicity and antibiotic resistance of coagulase-negative staphylococci (CNS) isolated from the maxillary and ethmoid sinuses of patients undergoing endoscopic sinus surgery for chronic sinusitis. PATIENTS AND METHODS: Ninety-three patients (63 males, 30 females) aged between 19 - 68 years, who had undergone functional endoscopic sinus surgery (FESS) for chronic sinusitis, were included in the study. Nasal mucosa, skin and adjacent structures were cleansed with povidone-iodine solution before surgery to prevent a probable contamination. In all patients, nasal swabs were taken before and after the application of povidone-iodine solution. Colonies isolated and identified as Staphylococci in cultures were further investigated for pathogenicity and antibiotic susceptibility. Slime test was used to determine the pathogenicity of CNS. The relationship between antibiotic resistance of pathogenic and non-pathogenic CNS was compared by chi2 analysis. RESULTS: While bacterial growth rate was 62.3% in nasal swab cultures taken before the application of povidone-iodine solution, it decreased to 12.9% after the application of solution. Microorganisms were isolated in 95.6% of cultures taken from maxillary sinuses and in 91.3% of cultures obtained from ethmoid sinuses during the FESS. The most frequently isolated microorganism in each of the sinuses was CNS. Slime test was carried out in 30 CNS isolated. Twelve of these were slime positive and 18 were slime negative. While 83.3% of CNS isolated was resistant to penicilin, all of CNS were sensitive to vancomycin and teikoplanine. The difference between slime positive and slime negative CNS for gentamicin and ciprofloxacin resistance was statistically significant (p<0.05). CONCLUSION: We consider that the pathogenicity tests like slime production and antimicrobial susceptibilities of CNS frequently isolated from the patients with chronic sinusitis should be investigated and also these microorganisms should be kept in mind in the selection of empiric treatment.

Adult↗
PubMed2004

Outbreaks of enteric infections caused by multiple pathogens associated with calves at a farm day camp.

BACKGROUND: Transmission of enteric pathogens at venues where the public contacts farm animals is a growing problem, particularly among children. In 2000 and again in 2001, enteric illness outbreaks caused by multiple pathogens occurred at a farm day camp for children in Minnesota. METHODS: Camp attendees were interviewed about illness history and potential exposures each year. Stool samples from children and calves at the camp were tested for enteric pathogens. RESULTS: Eighty-four illnesses were documented among camp attendees in the 2 outbreaks; laboratory-confirmed infections included Cryptosporidium parvum (17 cases), Escherichia coli O157:H7 (4), non-O157 Shiga toxin-producing E. coli (STEC) (7) and Salmonella enterica serotype Typhimurium and Campylobacter jejuni (1 each). Kindergarten-fourth grade children provided 1-on-1 care for a bottle-fed calf. Sixty of 83 calves tested carried at least 1 pathogen, including Giardia spp. (26 calves), C. parvum (25), non-O157 STEC (17), Campylobacter spp. (11), 3 serotypes of Salmonella enterica (10) and E. coli O157:H7 (2). Risk factors among children included caring for an ill calf and getting visible manure on their hands. Always washing hands with soap after touching a calf and washing hands before going home were protective. Prevention measures implemented in 2000 failed to prevent the second outbreak. CONCLUSIONS: Calves were the reservoir of multiple enteric pathogens for children at a farm day camp. Health care providers should consider numerous zoonotic pathogens in patients presenting with gastroenteritis after contact with cattle. Public health officials should help venue operators prospectively implement published guidelines to prevent zoonotic disease transmission.

Animals↗
PubMed2004

[Bacterial meningitis: determination of pathogens and therapeutic management].

Recent aspects of pathogen determination and therapeutic management are reviewed based on a clinical analysis of 50 of our adult patients with bacterial meningitis (BM). The sensitivity for detecting pathogens using gram-stained smears and cultures of CSF was high in untreated patients, but low in patients previously treated with antibiotics. Latex agglutination for antibodies of pathogens is rapid and has a potential for determining pathogens in partially treated meningitis. The PCR also has a potential for determining pathogens in pre-treated, culture-negative cases and for detecting whether the bacterial pathogen is resistant or sensitive to antibiotics. The initial empiric regimen of antibiotics has been modified with elevation in the detection rate of drug-resistant bacilli. The proportion of patients undergoing treatment with VCM and/or Carbapenems has recently increased at our department. A combination of dexamethasone under administration of antibiotics has also been established as effective in adult BM. On admission, some patients are difficult to diagnose as BM rather than herpes simplex encephalitis (HSVE). A serum CRP value of >2.0 mg/dl proved useful for such different diagnosis in our patients. The predictors of a poor outcome based on multivariate logistic analysis in our BM patients were level of unconsciousness and sepsis.

Adult↗
PubMed2005

Detection of sexually transmitted pathogens in patients with hematospermia.

BACKGROUND: Although the current literature attributes most cases of hematospermia to an infectious agent, identification of the specific pathogens involved has been limited. OBJECTIVES: To determine the prevalence of different pathogens in patients presenting with hematospermia to our sexually transmitted disease clinic. METHODS: Between January 1999 and January 2000, 16 patients presented to our STD clinic with hematospermia after other noninfectious pathologies had been excluded by a referring physician. After obtaining informed consent, subjects completed a questionnaire addressing symptoms and sexual behavior. First-void urine samples, as well as genitourinary and serum specimens were tested for Chlamydia trachomatis, Ureaplasma urealyticum and herpes simplex virus. Standard bacterial cultures were also performed. RESULTS: Laboratory testing detected a pathogen in 12 of the 16 males presenting with hematospermia. The sexually transmitted pathogens detected were herpes simplex virus in 5 patients (42%), Chlamydia trachomatis in 4 (33%), Enterococcus fecalis in 2 (17%), and Ureaplasma urealyticum in 1 (8%). In all cases in which a pathogen was identified, the appropriate antimicrobial agent was administered. Symptoms resolved for each patient following antimicrobial therapy. During a 1 year follow-up, all 12 patients remained free of disease. CONCLUSIONS: Recent advances in microbiologic diagnostic techniques have facilitated the detection of pathogens in patients with hematospermia, thereby enhancing the efficacy of treatment.

Adolescent↗
PubMed2005

[Identification and phylogenetic study of pathogenic bacteria causing ulcer disease of cultured Turbot (Scophthalmus maximus)].

An outbreak of ulcer disease of the cultured turbot Scophthalmus maximus L. occurred in an indoor farm in Haiyang, Shandong Province in the sweltering August of 2004 and caused significant mortality. At the beginning, infected turbots displayed sluggish swimming and anorexia. Several days later, the turbot eyes swelled, the fins and tail turned red, and the back gradually ulcerated. Dissection of the moribund fish showed that the ulcerative gills paled, the liver becamed bloodshot, the kidney and gallbladder swelled, the intestinal wall became filmy and bloodshot. The time course from appearance of disease signs to death lasted about a week. A dominant strain of bacteria, which was Gram-negative and short rod with single polar flagellum under electron microscope, was isolated from the diseased turbot and designated as H1. In artificial infection test, all fish of the experimental groups died in a week after intramuscularly injected with bacterial suspension, while the control group showed no signs in 10 d post-challenge. The moribund experimental fish had similar gross signs as the natural infected fish. The bacteria re-isolated from the challenged fish also had the same characteristics as H1, which proved that the isolate H1 was the pathogenic bacteria that triggered this ulcer disease. Different methods were used to identify the pathogenic bacteria. The identification result by API 20NE and API 20E system indicated that H1 was Aeromonas hydrophila, with 99% reliability and 61.5% respectively. While traditional biochemical identification revealed that H1 exhibited relatedness to Vibrio harveyi. In order to confirm the different result, a 1424 bp sequence of H1's 16S rDNA was amplified and compared with other Vibrio spp. in GenBank, homology analysis and phylogenetic study showed that H1 has the highest similarity to V. harveyi, with 99% identity. According to morphological features, physiological and biological characteristics and 16S rDNA homology comparison of the bacteria, the pathogenic bacteria were V. harveyi. Drugs sensitivity test showed that the pathogenic bacteria were highly sensitive to nitrofurantoinum and ceftriaxone sodium etc. This is the first report that V. harveyi was found as the pathogenic bacteria of cultured turbot in China. The research suggests that V. harveyi should be regarded as an important pathogen of turbot and can causes ulcer disease under conditions of high temperatures. Therefore, it is necessary to prevent against ulcer disease in culture turbot in summer.

Animals↗
PubMed2005

[Identification of genomic differences in avian pathogenic Escherichia coli using suppression subtractive hybridization analysis].

To identify unique DNA fragments associated with avian pathogenic Escherichia coli strains, suppression subtractive hybridization (SSH) was used. The genome of nonpathogenic E. coli K-12 strain MG1655 was subtracted from the genome of avian highly pathogenic strain E037 (serotype O78) resulting in the identification of 17 specific fragments. And the genome of avian low pathogenic E. coli strain E526 (serotype O2) was subtracted from the genome of avian highly pathogenic strain E058 (serotype O2) resulting in the identification of 32 specific fragments. Sequence homology analysis was done and four types of fragments were identified: plasmid sequences, phage sequences, sequences with known function and sequences without any currently known function. And 12 specific fragments that were not found in E. coli K-12 were identified from two avian E. coli strains. The results suggested that there were some genetic differences between the highly pathogenic strains and low pathogenic or nonpathogenic strains.

Animals↗