Background: Enteroaggregative Esherichia coli (EAEC) is a bacterium that can cause diarrhea. Enteroaggregative Esherichia coli (EAEC) has been one of important diarrheagenic E. coli. It is necessary to evaluate the role of EAEC in causing diarrhea in children. Objectives: The purposes of this study are to determine the prevalence \r\n', u'of EAEC in children with and without diarrhea and to evaluate the clinical symptoms of diarrhea caused by EAEC. Subjects and method:These 836 children living in Hanoi including 587 children with diarrhea and 249 controls have been selected for the study. Polymerase Chain Reaction in combination with the conventional method have been used to detect EPEe.They were treated at Saint \ufffd?Paul Hospital, Thanh Nhan Hospital and National Hospital of Pediatrics. Results: EAEC strains have been detected with the prevalence of 11.6% in children with diarrhea and of 7.2% in the controls. It shows a correlation of EAEC with diarrhea in children less than 2 years of age. The common clinical symptoms of EPEC diarrhea anT watery diarrhea, sunken, vomiting. Conclusion: Enteroaggregative Esherichia coli are attributable to about 12% of diarrheal cases in children. Watery diarrhea is the most commonly seen symptom. It would be of interest to perform further studies on diarrhea caused by EAEC in children in Hanoi. \r\n', u'
Diarrhea/ pathology ; diet therapy ; Escherichia coli/ pathogenicity

OBJECTIVETo investigate the etiologic value of diarrheagenic E. coil harboring genomic O island 28(OI-28) containing five putative virulence genes (Z0608, Z0609, Z0615, Z0634 and Z0635), which were related to RTX (Repeat in toxin) toxin family isolated from children with diarrheal disease in Taiyuan.

METHODSIn the study, 257 fecal samples from children with diarrheal disease collected in Shanxi Children's Hospital. Diarrheagenic E. coli and enteropathogenic bacteria were isolated and identified by conventional bacterial culture and typing specific diarrheagenic E. coli (EPEC, EIEC, ETEC and EHEC) diagnostic serum, while diarrheagenic E. coli harboring genomic 01-28 containing five putative virulence genes (Z0608, Z0609, Z0615, Z0634 and Z0635) were detected by PCR and DNA southern blot hybridization.

RESULTS206 strains (80.16%) of enteropathogenic bacteria were detected from 257 children with diarrhea disease, containing 149 strains (57.98%) of diarrheagenic E. coli and 57 strains(22.18%) of other entero-pathogenic bacteria. Among 3 strains (2.01%) of EPEC, 2 strains (1.34%) of ETEC, 2 strains (1.34%) EHEC were detected by typing specific serum, while all of the 142 strains (95.30%) isolated were suspected to be diarrheagenic E. coli. 21 strains (14.09%) of diarrheagenic E. coil harboring genomic O1-28 containing five putative virulence genes (Z0608, Z0609, Z0615, Z0634 and Z0635) were detected by polymerase chain reaction and DNA southen blot hybridization, 8 strains (5.37%) of diarrheagenic E. coli containing only one genomic OI-28 virulence gene, 2 strains (1.34%) of diarrheagenic E. coli containing two genomic OI-28 virulence gene. 21 children with diarrhea diseases caused OI-28-harboring E. coli containing five important putative virulence genes were among 0 to 3 years old (80.95%). These children correlating with OI-28-harboring E. coli did not present special clinical symptoms or signs.

CONCLUSIONThe diarrheagenic E. coil harboring genomic OI-28 was one of the important etiology for children with diarrheal disease in summer season.

Child ; China ; Diarrhea ; microbiology ; Escherichia coli ; genetics ; pathogenicity ; Escherichia coli Infections ; complications ; Genes, Bacterial ; Humans ; Virulence

Animals ; Cattle ; Chickens ; Escherichia coli Infections ; epidemiology ; microbiology ; Escherichia coli O157 ; isolation & purification ; pathogenicity ; Sheep ; Swine

Escherichia coli ; genetics ; pathogenicity ; Humans ; Infant, Newborn ; Virulence ; genetics

TcpC is a homolog of the Toll/interleukin-1 receptor (TIR) domain and is secreted by uropathogenic E. coli strain CFT073. TcpC can bind to MyD88, hereby exerting inhibitory effects on macrophages. TcpC represents an important virulence factor that promotes bacterial survival and pathogenicity. TcpC plays a critical role in urinary tract infection, particularly in the pathogenesis of pyelonephritis. In this review,the progress and prospects in TcpC research are discussed.
Animals ; Escherichia coli ; pathogenicity ; Escherichia coli Proteins ; physiology ; Humans ; Mice ; Pyelonephritis ; microbiology ; Urinary Tract Infections ; microbiology ; Virulence Factors ; physiology

OBJECTIVETo detect the "high pathogenicity island" of Yersinia enterocolitica WA in E. coli and the to provide evidence for theory base of bacterial evolution process and the different structures in different E. coil.

METHODSPolymerase chain reaction (PCR), nucleic acid hybridization in situ were used to detect and identify HPI. DNA sequencing was used to compare the gene homology of HPI among E. coli with Yersinia enterocolitica (Yen).

RESULTSThe irp2 and fyua genes of Yen HPI were investigated in E. coli strains. Among them, 30 strains were isolated from 93 Enterotoxigenic E. coli (ETEC) strains and 3 strains were positive in 10 strains Enteropathogenic (EPEC). HPI was also detected in Enteroaggregative E. coli (EAggEC) strain. In most of these isolates, HPI was bordered by an asntRNA locus, as in Yersinia sp. Through sequential comparison, the gene sequence homology was higher between in EPEC and EAggEC than ETEC and Yersinia enterocolica.

CONCLUSIONSETEC, EPEC and EAggEC were pathogenicity bacterias and many of them harboring HPI of Yen and the HPI had the same position in E. coli chromosome as Yersinia enterocolitica but the diversity of structure and sequence in these E. coli might suggest that the HPI of these different serotype E. coli were from different ancient bacterias. At the same time, the high positivity rate of HPI in E. coli might be crucial to virulence change, virulence evolution and virulence regulation in E. coli.

Bacterial Proteins ; analysis ; genetics ; Enterotoxins ; genetics ; Escherichia coli ; genetics ; pathogenicity ; Escherichia coli Infections ; microbiology ; Genes, Bacterial ; Receptors, Cell Surface ; genetics ; Virulence ; genetics ; Yersinia enterocolitica ; genetics ; pathogenicity

We encountered a patient with hemolytic uremic syndrome (HUS) with persistent isolation of shiga toxin-producing Escherichia coli (STEC) for 3 weeks despite of having no clinical symptoms. STEC has been recognized as an important food-borne pathogen that causes severe diseases such as HUS. We characterized this STEC strain via a polymerase chain reaction, reverse-passive latex agglutination and the slide agglutination method. In this STEC strain, stx2 (shiga toxin), eaeA, tir, iha (adherence genes), espADB (type III secretion genes), and hlyA, ehxA, clyA (hemolysin genes) were present. The O antigen of the strain was non-typable.
Child, Preschool ; Female ; Hemolytic-Uremic Syndrome/diagnosis/*microbiology ; Humans ; Shiga-Toxigenic Escherichia coli/*isolation & purification/*pathogenicity

OBJECTIVETo type and group the Shiga-toxin producing Escherichia coli O157:H7 strains isolated recent years in China to understand the epidemiological features caused by the pathogen.

METHODSPulsed field gel electrophoresis of large restriction fragments of bacterial chromosomal DNA was used.

RESULTSThe 51 isolates of E. coli O157:H7 collected in recent years in China could be divided into 8 Pulsed Field Gel Electrophoresis (PFGE) types based on the size and number of restriction fragments and patterns, that were digested by XbaI. Strains isolated from Ningxia province showed only two types- PFGE1 and PFGE2. Strains isolated in Xuzhou of Jiangsu province had 6 PFGE types. Isolates identified between 1986 - 1988 belonged to PFGE7. Strains isolated from patients in 1999 - 2000 were PFGE5 and PFGE3. Strains isolated from stool samples of domestic animal, food and vegetable were PFGE3 - 6, of which the predominant type was PFGE5. All of the 5 strains isolated from patients with diarrhea and hemolytic uremic syndrome (HUS) belonged to PFGE type 5, which was the dominant type of the isolates from stool samples of domestic animal and samples of food and vegetable contaminated.

CONCLUSIONData suggested that the cluster patients with diarrhea and HUS might have been related to the pathogens from domestic animas and contaminated food or vegetables. The distribution of PFGE types also varied in different provinces of China.

Electrophoresis, Gel, Pulsed-Field ; Escherichia coli O157 ; classification ; genetics ; pathogenicity ; Genotype ; Humans ; Shiga Toxin ; biosynthesis

OBJECTIVE7 variable but nonculturable-state strains of Enterotoxigenic Escherichia coli (ETEC) during the routine bacterial subculture were found in our lab and their morphology and antigen studied. Biological features, antigens and pathogenicity of the revertants were also tested and compared to that of the initial strains in order to detect their variations.

METHODSBiological variations between the variable but nonculturable-state and the revertant of every strain were detected, using the routine gram-staining, reverting the isolates in animal intestinal, reverting their pathogenicity, serological agglutination, biochemical identifications and antibiotic resistance tests.

RESULTSFor the 7 variable but nonculturable-state strains of ETEC,other than the trains that had changed into sphero vegetale cells, there were no other obvious variations found. However, high pathogenicity of these strains still remained.

CONCLUSIONThe presence of variable but nonculturable-state strains suggested that the routine method of bacteria storage should be changed and more attention should be paid to realize the existence of this kind of bacteria during the routine surveillance of the communicable diseases.

Antigens, Bacterial ; Drug Resistance, Bacterial ; Enterotoxigenic Escherichia coli ; drug effects ; immunology ; pathogenicity ; Microbiological Techniques

OBJECTIVETo study the two metal catalysts Ag/Al2O3 and Cu/Al2O3 that interdict the transmission pathway for SARS and other respiratory infectious diseases.

METHODSTwo metal catalysts Ag/Al2O3 and Cu/Al2O3 were pressed into wafers. One hundred microL 10(6) TCID50/mL SARS-CoV, 100 microL 10(6) PFU/mL recombinant baculovirus expressing hamster's prion protein (haPrP) protein and roughly 10(6) E. coli were slowly dropped onto the surfaces of the catalyst wafers and exposed for 5 and 20 min, respectively. After eluted from the surfaces of wafers, the infectivity of viruses and propagation of bacteria were measured. The expression of PrP protein was determined by Western blot. The morphological changes of bacteria were observed by electronic microscopy.

RESULTSAfter exposure to the catalysts surfaces for 5 and 20 min, the infectivity of SARS-CoV in Vero cells and baculovirus in Sf9 cells dropped down to a very low and undetectable level, and no colony was detected using bacteria culture method. The expression of haPrP protein reduced to 21.8% in the preparation of Sf9 cells infected with recombinant baculovirus exposed for 5 min and was undetectable exposed for 20 min. Bacterial membranes seemed to be cracked and the cytoplasm seemed to be effluent from cell bodies.

CONCLUSIONExposures to the surfaces of Ag/Al2O3 and Cu/Al2O3 destroy the replication and propagation abilities of SARS-CoV, baculovirus and E. coli. Inactivation ability of metal catalysts needs to interact with air, utilizing oxygen molecules in air. Efficiently killing viruses and bacteria on the surfaces of the two metal catalysts has a promising potential for air-disinfection in hospitals, communities, and households.

Aluminum Oxide ; Animals ; Baculoviridae ; pathogenicity ; Catalysis ; Cercopithecus aethiops ; Copper ; Cricetinae ; Disinfection ; methods ; Escherichia coli ; pathogenicity ; Prions ; metabolism ; SARS Virus ; pathogenicity ; Silver ; Vero Cells