OBJECTIVETo survey an outbreak of acute gastroenteritis in Lulong County and analyze the cause of the disease.

METHODSEpidemiological methods were applied to investigate an outbreak of acute gastroenteritis occurred in June 2000 in Lulong County. Stool specimens were collected from diarrhea patients and were tested for human calicivirus by ELISA and RT-PCR. The products of RT-PCR were cloned and sequenced, then phylogenetic analysis was carried out.

RESULTSIn total, 736 farmers were surveyed, among them 134 had acute gastroenteritis, the attack rate was 18.20%, and one elderly patient died. The age of patients was from 1 to 77 years and the incidence of the disease among young people was higher with a peak in June 25 through 30. Six stool specimens were tested for caliciviruses by ELISA and 3 were positives, one of them was confirmed by RT-PCR and belonged to norovirus genotype GI/2. No other pathogens were detected.

CONCLUSIONHuman calicivirus was confirmed to be the cause of the outbreak of acute gastroenteritis.

Acute Disease ; Caliciviridae ; genetics ; isolation & purification ; Caliciviridae Infections ; epidemiology ; China ; epidemiology ; Disease Outbreaks ; Enzyme-Linked Immunosorbent Assay ; Feces ; virology ; Gastroenteritis ; epidemiology ; virology ; Humans ; RNA, Viral ; genetics ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo investigate the epidemiological characteristus of human caliciviruses (HuCVs) among children under 5 years of age with acute diarrhea and to estimate the disease burden in Lulong county.

METHODSHuCVs were detected by enzyme linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR). Some PCR amplicons were cloned and sequenced. Phylogenetic tree was constructed for strain characterization. The rate of HuCVs-attributed hospitalization was estimated according to the positive rate of HuCVs detection in fecal specimens collected from hospitalized diarrhea patients.

RESULTSBetween July 1999 and June 2001, 708 fecal specimens were collected, of which 393 rotavirus-negative and 5 rotavirus-positive specimens were detected for HuCVs. Thirty-one point six percentage of fecal specimens from patients with diarrhea was HuCVs positive. Among inpatients, HuCVs positive rate was 17.5%. HuCVs detection was mainly distributed in 3 - 17 mouth-old children, in winter. All 11 strains belonged to NLV GII in which 6 strains GII-3, 2 strains GII-4 and 3 strains GII-7, and they shared 55.1% - 100% nucleotide identity. NLV GII-4 and GII-7 were identified in 2000, while NLV GII-3 and GII-7 in 2001. The preliminary estimate of HuCVs-attributed hospitalization rate was 3.6 per thousand.

CONCLUSIONHuman caliciviruses with different genotypes circulated among children in Lulong county with GII NLVs were the prevalent strains. The disease burden of HuCVs was second to rotavirus.

Acute Disease ; Age Factors ; Caliciviridae ; genetics ; immunology ; Caliciviridae Infections ; complications ; epidemiology ; Child, Preschool ; China ; epidemiology ; Dysentery ; epidemiology ; etiology ; Enzyme-Linked Immunosorbent Assay ; Humans ; Infant ; Inpatients ; statistics & numerical data ; Phylogeny ; Reverse Transcriptase Polymerase Chain Reaction ; Seasons

OBJECTIVETo investigate the protective effect of hepatocyte growth factor (HGF) on protein synthesis in rat cardiomyocytes exposed to gamma-ray irradiation.

METHODSPrimary cultured cardiomyocytes were irradiated with single-dose (20 Gy) gamma ray in the absence or presence of HGF (40 ng/ml) added in the cell culture 3 h before the exposure. Forty-eight hours after irradiation, the total cellular protein was measured and cell cycle analyzed by flow cytometry. The cardiomyoctes were also infected with AdGFP 48 h after irradiation and the fluorescence intensity of the green fluorescence protein (GFP) in the cells determined by flow cytometry 48 h after infection.

RESULTSThe protein synthesis was decreased significantly in the irradiated cardiomyocytes as compared with the control group (P<0.01), but was remedied significantly by incubation of the cells with HGF before the exposure (P<0.05). Flow cytometry revealed much lower mean fluorescence intensity (MFI) of GFP in irradiated cardiomycytes than in cells without the exposure (P<0.01); The MFI was higher in HGF-treated cardiomyocytes than in cells without HGF treatment following the exposure (P<0.01).

CONCLUSIONGamma ray irradiation inhibits protein synthesis in cardiomyocytes, and HGF may attenuate this effect of gamma ray exposure for cardiomyocyte protection.

Animals ; Animals, Newborn ; Cell Cycle ; drug effects ; radiation effects ; Cells, Cultured ; Flow Cytometry ; Gamma Rays ; Green Fluorescent Proteins ; genetics ; metabolism ; Hepatocyte Growth Factor ; pharmacology ; Microscopy, Fluorescence ; Myocytes, Cardiac ; cytology ; metabolism ; Protein Biosynthesis ; drug effects ; radiation effects ; Rats ; Rats, Wistar

OBJECTIVETo observe the impact of specific short hairpin RNA (shRNA) targeting survivin gene on tumorigenesis and angiogenesis of human brain glioblastoma U251 cells in vivo of nude mice.

METHODSU251 cells, U251-SR cells transfected stably with shRNA eukaryotic expression vector pWH1-SR targeting survivin gene, and U251-P cells transfected stably with blank pWH1 vector, were inoculated respectively into subcutaneous tissue in flank of 15 nude mice (each group 5 mice), and the tumor growth status was observed and measured. Protein expressions of survivin, proliferating cell nuclear antigen (PCNA) and factor VIII related antigen (F VIII RAg) were investigated by immunohistochemistry SABC method, apoptotic cells were screened by TUNEL method, furthermore proliferative index (PI), apoptotic index (AI) and microvessel density (MVD) were measured respectively in each group of tumor specimens.

RESULTSComparing with those in U251 and U251-P groups, in U251-SR group, the tumorigenesis time delayed, tumor grew slowly, both tumor volume and tumor weight decreased significantly (P < 0.01 for both); Survivin protein expression was down-regulated markedly; PI and MVD decreased significantly, whereas AI increased remarkably (P < 0.01 for all).

CONCLUSIONSThe specific shRNA targeting survivin gene can inhibit significantly tumorigenesis and angiogenesis of U251 cells in vivo.

Animals ; Apoptosis ; Brain Neoplasms ; metabolism ; pathology ; Cell Line, Tumor ; Female ; Glioblastoma ; metabolism ; pathology ; Humans ; Inhibitor of Apoptosis Proteins ; Male ; Mice ; Mice, Nude ; Microtubule-Associated Proteins ; biosynthesis ; genetics ; Neoplasm Transplantation ; Neovascularization, Pathologic ; pathology ; RNA Interference ; RNA, Small Interfering ; genetics ; Repressor Proteins ; Transfection

OBJECTIVETo establish an ideal CCl4 drug-induced liver injury model in vitro.

METHODTraditional method and improved method were adopted for preparing CCl4 injury liquid and drug-induced human liver HepG2 cell injury. Cell morphological change was observed under a bright-field microscope. The level of alanine aminotransferase (ALT) in supernatant was detected by biochemical method. 4-Methyl-tetrazolium (MTT) chromatometry was adopted for determining cell activity.

RESULTThe improved method showed better CCl4-induced injury effect than the traditional method. With the increase in the concentration of CCl4 injury liquid, the ALT level significantly increased, whereas the cell activity notably decreased. Particularly, 70% CCl4 injury liquid use for 4 hours could achieve the best injury effect.

CONCLUSIONThe improved method could be used to establish an ideal CCl4 drug-induced liver injury model in vitro, which can lay foundation for further in vitro studies.

Alanine Transaminase ; metabolism ; Aspartate Aminotransferases ; metabolism ; Carbon Tetrachloride ; adverse effects ; Chemical and Drug Induced Liver Injury ; enzymology ; etiology ; Hep G2 Cells ; Humans ; Liver ; drug effects ; enzymology ; injuries ; Models, Biological ; Superoxide Dismutase ; metabolism

Objective To determine the hosts of hantavirus (HV) and its molecular epidemiological characteristics, to provide evidence for prevention and control on hemorrhagic fever with renal syndrome (HFRS). Methods Rodents were captured by a special trap within the residential area. The antigens of HV in lung tissues were detected by direct immuno-fluorescence assay (DFA). Nucleotide sequences of HV were amplified by RT-PCR with HV genotype-specific primer. The amplified genes were then sequenced. Phylogenetic tree were built on nucleotide sequence with Clusta1X 1.83 software. Results 1421 rodents were captured and classified into 8 species of 4 Genera in the epidemic area within 10 counties of Chuxiong prefecture, Yunnan province, between 2005 and 2006. Out of the 1421 rodents, 1056 (74.31%) of them were Rattus norvegicas and 280 (19.70%) belonged to Rattus flavipectus. The antigens of HV were detected by DFA in lung tissues and the total positive rate of HV was 5.15% (53/ 1029). After applying the sequencing nucleotide method to the 53 positive specimens, data showed that 21 specimens were positive and all of them belonged to Seoul type ( 15 samples were from Rattus norvegicus, 4 samples Rattasflavipectas, 2 samples Rattus nitidas). The partial S segments from 12 specimens were sequenced which appeared homologic with R22, L99 and HLD65 from GenBank in relatively high level (87.1%-99.7%). When compared to 76-118 strain of Hantaan type, their homologic degree was only 64.4%-69.1%. Results from Phylogenetic analysis showed that 12 specimens belonged to Seoul type. As for their homology, they were significantly similar to Seoul type and could be tentatively divided into two subtypes S1 and S3. Conclusion It was confirmed that the Seoul type virus, as HFRS' s pathogenetic agent mainly carried by rats, prevailed widely in Chuxiong prefecture. Owing to the local ecological environment, we also noticed the characteristics of different HV subtypes among Seoul type.

OBJECTIVE: To investigate the changes in bacterial flora in fecal samples, at the tumor loci and in adjacent mucosa in patients with colorectal cancer (CRC). METHODS: We collected fecal samples from 13 patients with CRC and 20 healthy individuals and tumor and adjacent mucosa samples from 6 CRC patients. The differences in bacterial composition between the fecal and mucosa samples were analyzed with 16S rDNA sequencing and bioinformatics methods. We also detected the total number of bacteria in the feces using flow cytometry, isolated and identified the microorganisms in the fecal and mucosa samples using common bacterial culture media. We further tested the effects of 7 isolated bacterial strains on apoptosis of 3 CRC cell lines using lactate dehydrogenase detection kit. RESULTS: The bacterial α-diversity in the feces of healthy individuals and in adjacent mucosa of CRC patients was significantly higher than that in the feces and tumor mucosa in CRC patients (P < 0.05). Lactobacillaceae is a specific bacteria in the feces, while Escherichia, Enterococcus, and Fusobacterium are specific bacteria in tumor mucosa of CRC patients as compared with healthy individuals. Cell experiment with3 CRC cell lines showed that Bacteroides fragilis isolated from the tumor mucosa of CRC patients produced significant inhibitory effects on cell proliferation (P < 0.0001), while the isolated strain Fusobacterium nucleatum obviously promoted the proliferation of the cell lines (P < 0.001). CONCLUSION The bacterial flora in the feces, tumor mucosa and adjacent mucosa of CRC patients is significantly different from that in the feces of healthy individuals, and the fecal flora of CRC patients can not represent the specific flora of the tumor mucosa. Inhibition of F. nucleatum colonization in the tumor mucosa and promoting B. fragilis colonization may prove beneficial for CRC treatment.
Bacteria ; Colorectal Neoplasms/pathology* ; Feces/microbiology* ; Gastrointestinal Microbiome ; Humans ; Intestinal Mucosa