cdh23 affects congenital hearing loss through regulating purine metabolism.

Introduction: The pathogenic gene CDH23 plays a pivotal role in tip links, which is indispensable for mechanoelectrical transduction in the hair cells. However, the underlying molecular mechanism and signal regulatory networks that influence deafness is still largely unknown. Methods: In this study, a congenital deafness family, whole exome sequencing revealed a new mutation in the pathogenic gene CDH23, subsequently; the mutation has been validated using Sanger sequencing method. Then CRISPR/Cas9 technology was employed to knockout zebrafish cdh23 gene. Startle response experiment was used to compare with wide-type, the response to sound stimulation between wide-type and cdh23-/-. To further illustrate the molecular mechanisms underlying congenital deafness, comparative transcriptomic profiling and multiple bioinformatics analyses were performed. Results: The YO-PRO-1 assay result showed that in cdh23 deficient embryos, the YO-PRO-1 signal in inner ear and lateral line neuromast hair cells were completely lost. Startle response experiment showed that compared with wide-type, the response to sound stimulation decreased significantly in cdh23 mutant larvae. Comparative transcriptomic showed that the candidate genes such as atp1b2b and myof could affect hearing by regulating ATP production and purine metabolism in a synergetic way with cdh23. RT-qPCR results further confirmed the transcriptomics results. Further compensatory experiment showed that ATP treated cdh23-/- embryos can partially recover the mutant phenotype. Conclusion: In conclusion, our study may shed light on deciphering the principal mechanism and provide a potential therapeutic method for congenital hearing loss under the condition of CDH23 mutation.

Successful Endoscopic Resection of Primary Rectal Mucosa-Associated Lymphoid Tissue Lymphoma by Endoscopic Submucosal Dissection: A Case Report.

Mucosa-associated lymphoid tissue (MALT) lymphoma arises in extra-nodal sites from the malignant transformation of B lymphocytes that are mainly triggered by infection or autoimmune process. MALT lymphoma is frequently detected in the gastrointestinal tract. As the causal relationship between Helicobacter pylori (H. pylori) infection and gastric MALT lymphoma, it was well-established that early-stage gastric MALT lymphoma could be cured by H. pylori eradication, and about 50-95% of cases achieved complete response with anti-H. pylori treatment. Compared to the stomach which is the most involved site due to the high prevalence of H. pylori infection, the colorectum is rarely affected. Primary rectal MALT lymphoma is a rare malignancy, and there are no specific therapeutic strategies so far. Here we report a case of rectal MALT lymphoma successfully resected by endoscopic submucosal dissection (ESD). ESD serves as a novel strategy to cure small localized rectal MALT lymphomas to avoid unnecessary surgery or chemo-radiotherapy.

Gastric Mucosa-Associated Lymphoid Tissue Lymphomas Diagnosed by Jumbo Biopsy Using Endoscopic Submucosal Dissection: A Case Report.

The stomach is the most common primary site of mucosa-associated lymphoid tissue (MALT) lymphoma, and sometimes the histopathological diagnosis is particularly difficult. An endoscopic forceps biopsy is the primary diagnostic test, but false negative results are very common. Therefore, a jumbo biopsy is essential for accurate diagnosis of clinically suspected cases. Here we diagnosed two cases of gastric MALT lymphomas using endoscopic submucosal dissection (ESD). The first patient was suspected of gastric lymphoma at the first endoscopic forceps biopsy, but the second endoscopic forceps biopsy showed chronic inflammation. The second patient was also firstly diagnosed with chronic inflammation by endoscopic forceps biopsy. Both cases were finally confirmed with the diagnosis of gastric MALT lymphoma by jumbo biopsy using ESD. The application of ESD can provide a new diagnostic strategy for clinically suspicious cases of gastric MALT lymphoma with negative endoscopic forceps biopsy.

Observational study of colonoscopy techniques used for acute colorectal obstruction: A single-center experience.

The prevalence of acute colorectal obstruction at the hospital setting is high. There is need for improvement in the quality of colonoscopy for relieving obstruction. A retrospective, uncontrolled, open-label study was conducted, with the aim of documenting the causes of acute colorectal obstruction and the quality of colonoscopy practice in managing obstruction at a university hospital in China. A total of 61 adult patients with acute colorectal obstruction treated with urgent colonoscopy between February, 2011 and January, 2016 were identified at the Endoscopic Unit of Tongji Hospital (Wuhan, China). The technique success rate was the primary outcome. The etiology was mainly related to malignant diseases, including colorectal cancer in 53 patients (86.9%) and advanced peritoneal serous carcinoma leading to extrinsic colonic compression in 1 patient (1.6%). Benign causes of obstruction included foreign bodies in 3 patients (4.9%) and fecal impaction in 2 patients (3.3%); furthermore, anastomotic strictures were found in 2 patients (3.3%). The technique success rate was 98.4% (60/61). All colorectal cancer patients who underwent urgent colonoscopy were admitted to the Department of Surgery for placement of a self-expanding metallic stent; 1 patient who had an extracolonic malignancy underwent placement of a transanal colonoscopic decompression tube as palliative therapy and 2 patients with anastomotic strictures underwent endoscopic balloon dilation. Furthermore, colonoscopy was used for extracting the foreign body, as well as removing fecal stones in all the patients. In conclusion, urgent colonoscopy as a minimal invasive approach is associated with certain advantages for diagnosing and managing acute colorectal obstruction. Furthermore, experienced operators achieved a better outcome when managing colorectal obstruction.

Characterization of the new GII.17 norovirus variant that emerged recently as the predominant strain in China.

Human noroviruses are the most important viral pathogens causing epidemic acute gastroenteritis, in which the GII.4 viruses have been predominant worldwide for the past decades. During 2014-2015 winter season, a new GII.17 variant emerged as the predominant virus in China surpassing the GII.4 virus in causing significantly increased acute gastroenteritis outbreaks. Genome sequences of the new GII.17 variant was determined and compared with other GII.17 noroviruses, revealing residue substitutions at specific locations, including the histo-blood group antigen-binding site and the putative antigenic epitopes. Further study of GII.17 outbreaks focusing on host susceptibility showed that the new GII.17 variant infected secretor individuals of A, B, O and Lewis types. Accordingly, the P particles of the new GII.17 variant bound secretor saliva samples of A, B, O and Lewis types with significantly higher binding signals than those of the P particles of the previous GII.17 variants. In addition, human sera collected from the outbreaks exhibited stronger blockade against the binding of the new GII.17 P particles to saliva samples than those against the binding between the P particles of previous GII.17 variants and saliva samples. Taken together, our data strongly suggested that the new GII.17 variant gained new histo-blood group antigen-binding ability and antigenic features, which may contribute to its predominance in causing human norovirus epidemics.

Endoscopic mucosal resection of duodenal bulb adenocarcinoma with neuroendocrine features: An extremely rare case report.

Duodenal adenocarcinoma, especially duodenal bulb with neuroendocrine features (NEF), is extremely rare. Here, we report one such case of duodenal bulb adenocarcinoma with neuroendocrine features. A 63-year-old Han Chinese woman was admitted to our department with the diagnosis of a duodenal bulb polyp and underwent an endoscopic mucosal resection. The pathological findings confirmed it as duodenal bulb adenocarcinoma with NEF. The patient remains curative after one and half a years of follow-up. Duodenal adenocarcinoma with NEF might be a low malignant neuroendocrine tumor rather than a conventional adenocarcinoma. Endoscopic treatment, including endoscopic mucosal resection, might be an ideal option for the adenocarcinomas with NEF.

[The molecular epidemiology characteristics of norovirus in environment and clinical samples in Guangzhou from 2009 to 2011].

OBJECTIVE: To investigate the molecular epidemiological characteristics of norovirus in Guangzhou from 2009 to 2011. METHODS: A total of 183 water samples, 1162 seafood samples and 1066 diarrhea stool specimens were collected from January 2010 to May 2011, June 2009 to June 2011 and July 2009 to December 2010 respectively in Guangzhou. Norovirus was detected by real time reverse transcript-PCR (qRT-PCR). The partial polymerase gene was amplified from norovirus positive samples, then sequenced and compared with the sequences of norovirus in GenBank. The phylogenetic tree was created. RESULTS: The positive rate was 19.67% (36/183), 8.26% (96/1162) and 37.05% (395/1066) in water samples, seafood and diarrhea patients respectively. Noroviruses from positive samples could be divided into 10 representative strains, in which 7 representative strains of genotype of 208 samples was type G2-4. The sequences from water, seafood and stool specimens were highly homologous with the similarity of 94% - 100%. CONCLUSION: In Guangzhou, the predominant Norovirus genotype was G2-4 and the positive rate of samples was high.

[An epidemiological investigation on a food-born outbreak of noroviru caused by Sydney 2012 G II.4 strain].

OBJECTIVE: To identify the source of infection, route of transmission and risk factors related to a cluster of acute gastroenteritis cases in a university of Guangzhou. METHODS: Cases were identified according to the definition. Descriptive epidemiological approaches and case-control study designs were employed in the analysis. All the samples were tested for norovirus by RT-PCR. Positive samples were subjected to both nucleotide sequence and homology analysis. RESULTS: A total of 141 cases related to norovirus gastroenteritis were identified in January 8 to 21, 2013, with the attack rate as 8.5 per thousand (141/16,600). The peak in morbidity was seen on January 8 to 9. No clustering was found in different classes or dormitories. Results from the case-control study revealed that early cases were infected in Restaurant A (OR = 3.46, 95% CI: 1.07-11.16) and the cold shredded chicken set meal (OR = 17.82, 95% CI: 4.46-78.17) served at lunch (OR = 4.34, 95% CI: 1.18 -17.37) on January 7 was under suspicion. A total of 266 samples, including rectal swabs from the patients and kitchen wokers, leftover food and environmental swabs, were collected. Twenty-one samples (collected from 17 persons) were positive for norovirus by RT-PCR. About 29.6% (8/27) of the kitchen workers in the Restaurant A were tested positive for the virus. The pathogen was identified as the new norovirus genotype II.4 variant, termed Sydney 2012. The virus strains isolated from the patients among student and staff and the kitchen workers were 100% identical in their nucleotide sequence. CONCLUSION: This was the first reported acute gastroenteritis outbreak caused by the new norovirus genotype II.4 variant, Sydney 2012, which showed that the food was contaminated by the asymptomatic kitchen workers who carried the virus.

[Relation between clinical detection rates of the novel influenza virus A/H1N1 RNA in confirmed patients in Guangzhou and the disease course].

OBJECTIVE: To study the relation of the detection rates of the novel influenza virus A/H1N1 RNA in clinically confirmed patients in the 2009 pandemic with the age distribution of the patients and the disease course. METHODS: A total of 151 clinical patients with H1N1 infection were enrolled in this study, from whom 833 dynamic throat swab samples were obtained for detecting the H1N1 RNA using real-time PCR. A statistical analysis of the age distribution was performed among the patients with different disease courses. Chi-square for trend test was used to study the correlation between the detection rates of H1N1 RNA and the time of disease onset. RESULTS: The majority of patients were young with their ages ranging from 10 to 20 years (57.26%) and 20 to 30 years (22.18%). Chi-square for trend test revealed that the positivity rates of the throat swabs in the patients decreased with the prolongation of the disease course (chi(2)=9.784, P=0.002). CONCLUSION: Most of the H1N1 patients are young within the age range of 10-30 years, and the longest disease course can exceed 10 days. The positivity rates of throat swabs from the H1N1 patients decreases with the prolongation of the disease course.

[Analysis of epidemiologic feature and genetic sequence of Sapovirus in China].

To investigate epidemiologic feature and genetic variance of Sapovirus among children in China, fecal specimens were collected from children under 5 years old with acute diarrhea from Feb 2006 to Jan 2007 in nine provinces including Anhui, Fujian et al. A total of 1,110 fecal samples were detected for Sapovirus by reverse transcriptase-PCR (RT-PCR). Ten samples (0.9%) were positive for Sapovirus. The PCR products were then sequenced and analysed by phylogenetic tree. The results indicated that the detected Sapovirus strains were classified into two genogroups and three genotypes, including G I/1, G I/3, G II/3.

[Investigation on a seasonal influenza accompanying with the first locale novel A/H1N1 influenza outbreak in China].

OBJECTIVE: To timely summarize past experience and to provide more pertinent reference for control and prevention in A/H1N1 cases in influenza season. METHODS: During May 25 to 31, 2009, 2 secondary community cases caused by a influenza A/H1N1 imported case. In the close contacts of 3 A/H1N1 cases, 14 had some aspirator symptoms onset, such as fever (> or = 37.5 degrees C), cough, sore throat and etc. Laboratory tests excluded the infection of A/H1N1 influenza. For throat swab test for the 14 cases, 7 were tested for seasonal influenza virus. A face-to-face or telephone interview was conducted by CDC staff to collect information of 62 close contacts. RESULTS: Of 14 fever cases, there was no significant by differences by age[15-age group: 19.2% (5/26), over 25-age group: 25.0% (9/36); chi(2) = 0.287, P = 0.592]; by sex group [24.0% (6/25) for male and 21.6% (8/37) for female; chi(2) = 0.048, P = 0.826], by working units [dressing and design, photograph, saleroom and others, consumer group: 42.1% (8/19), 27.3% (3/11), 12.5% (2/16) and 6.3% (1/16); chi(2) = 7.653, P = 0.054], by dormitory style [dormitory style = 33.3% (4/12), non-dormitory style = 29.4% (10/34); chi(2) = 0.699, P = 0.403]. All the cases had fever (37.5 - 37.9 degrees C), no case had diarrhea. One in 3 A/H1N1 cases had diarrhea. All the 14 cases were negative result for A/H1N1 RNA. Six from 7 cases were positive for seasonal influenza test. CONCLUSION: This was a seasonal influenza outbreak happened in the close contacts of first confirmed A/H1N1 cases in community in mainland China. It showed that we should exclude the seasonal influenza in the investigation of A/H1N1 cases in the seasonal influenza period in some time. It is necessary to take effective measure to strengthen the control and prevention of seasonal influenza.

[A comparative study of the diagnostic value of endoscopic ultrasonography with pathological features of upper gastrointestinal mesenchymal tumors].

OBJECTIVE: To study the pathological and immunohistochemical features of upper gastrointestinal mesenchymal tumors (GIMTs) and compare them with endoscopic ultrasonographic (EUS) characteristics so as to evaluate the diagnostic value of EUS in upper digestive tract GIMTs. METHODS: Seventy-two pathological specimens of upper digestive tract GIMTs (34 surgical specimens and 38 endoscopic mucosal resection (EMR) specimens) were collected. The pathological features and the expression of CD(117), CD(34), SMA and S-100 were observed by immunohistochemical method with light microscope. The pathological types and characteristics were determined by pathologists and compared with the layer of origin and sonographic characteristics determined with preoperative EUS. RESULTS: In the 72 cases of upper digestive tract GIMTs, 37 cases were diagnosed as stromal tumor with pathological and immunohistochemical methods (51.4%); 21 of them were malignant, accounting for 56.7% of the stromal tumors. Thirty-four cases were diagnosed as leiomyoma (47.2%) and 1 case as schwannoma (1.4%). In the 72 GIMTs cases, 40 were esophageal GIMTs. EUS showed that 38 cases were originated from the muscularis mucosae layer; 33 of them were leiomyoma and 5 stromal tumor. The 2 cases originating from the muscularis propria layer which were both stromal tumors. Thirty-two cases were gastric GIMTs, EUS showed that 2 cases originating from the muscularis mucosae layer were gastric stromal tumor. Of the 30 cases originating from the muscularis propria layer, 28 cases were stromal tumor, 1 case was leiomyoma and 1 case was schwannoma. The sensitivity and the specificity of EUS in distinguishing benign and malignant stromal tumors according to sonographic characteristics were 81.0% and 93.8% respectively. CONCLUSION: Stromal tumor is more common in stomach mesenchymal neoplasms and is more often originated from the muscularis propria layer in EUS; leiomyoma is more common in esophagus and is more often originated from the muscularis mucosae layer. The diagnostic sensitivity and specificity of EUS are high in distinguishing benign and malignant character of upper digestive tract GIMTs. EUS plays an important role in guiding the clinical management of upper digestive tract GIMTs.

Emergence of the GII4/2006b variant and recombinant noroviruses in China.

Noroviruses are an important cause of acute gastroenteritis. Increasing data showed that the GII-4 strains are predominant worldwide and new GII-4 variants emerge every 1-2 years causing major epidemics. Surveillance of gastroenteritis in hospitalized children under 5 years of age in China is described. Among 1,110 specimens, 114 (10.3%) were positive for noroviruses, which was higher than adenoviruses (7.6%), astroviruses (3.5%), and sapoviruses (0.9%) and only lower than group A rotaviruses (40.6%). Thirty-eight of the 114 positive norovirus cases were co-infected with other enteric viruses. Five norovirus genotypes (GI-2, GI-4, GII-3, GII-4, and GII-14) were detected, with GII-4/2006b the most predominant type (64.9%). The reported recombinant of GII-3 capsid and GII-4 polymerase described previously was also detected frequently and a recombinant of GII-14 capsid and GII-6 polymerase was found for the first time. This study suggests that continual surveillance focusing on strain variation and dynamic change is important for understanding the epidemiology and development of a strategy for disease control and prevention.

[A research on rotaviral diarrhea outbreak in Guangxi Province].

OBJECTIVE: To analyze epidemiological characters of an outbreak of rotavirus diarrhea in Daxing County, Guangxi Province. METHODS: Rotavirus-positive specimens were identified by ELISA kit. G/P typing assays were confirmed with multiplex seminested RT-PCR. Full-length VP7 genes of 4 positive specimens were amplified and analyzed. RESULTS: 30 cases of Rotavirus-positive were identified from 64 specimens. The attack rate was 46.9%, and G/P typing was G1P[8]. A change of VP7 amino acid residue is at positions 68. CONCLUSION: G1P[8] rotavirus is the etiologic agents of this diarrhea outbreak. In addition, adults were included in this outbreak.

[Epidemiological investigation of an outbreak of acute gastroenteritis caused by human calicivirus in Lulong County].

OBJECTIVE: To survey an outbreak of acute gastroenteritis in Lulong County and analyze the cause of the disease. METHODS: Epidemiological 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. RESULTS: In 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. CONCLUSION: Human calicivirus was confirmed to be the cause of the outbreak of acute gastroenteritis.

[Investigation of human calicivirus (HuCV) diarrhea among infantile and young children in China, 1999--2005].

Human calicivirus (HuCV) has been well known as an important pathogen of outbreak and sporadic acute nonbacterial gastroenteritis worldwide. To investigate epidemiological feature and genetic diversity of HuCV among children in China, fecal specimens were collected from children under 5 years of age with acute diarrhea at 13 hospitals in different provinces across China. The study was performed year-round from January 1999 to June 2005. Fecal specimens were tested for bacteria and rotavirus first and the negative specimens then were tested for HuCV using ELISA and RT-PCR. PCR amplicons were cloned and sequenced for strain characterization. A total of 4426 rotavirus- negative fecal samples were screened. From these, 840 (19%) were positive for HuCV by either or both ELISA (14%) and RT-PCR (9.6%). HuCV infection occurred year-round with an epidemic in each winter (October-January) and mainly in children at 6 -- 17 months of age. Of 151 HuCV strains characterized, 146 belong to norovirus (NV, 96.7%) and 5 were sapoviruses (SV). Among norovirus strains, genotype GG II/4 was most common (99/146), followed by GG II/3 (22/146), GG II/5 (8/146), and 2 strains of each of GG II/6, GG II/7, GG II/8, and GG I/2, the other 9 strains of NV GG II were unique, potentially belonging to new genotypes. These results plus the epidemiology data suggested that HuCVs are an important cause of severe diarrhea in Chinese children that were under reported due to a lack of a simple diagnostic assay. The finding of the potential new genotypes indicates that the current assays need to be improved for broader detection and besides, a continual surveillance for better understanding the epidemiology the disease burden and the searching for new strains of HuCVs is necessary.

[Etiological study on viral diarrhea among children in Lanzhou, Gansu, from July 2004 through June 2005].

OBJECTIVE: To study molecular epidemiology of four major etiological viruses among children with acute diarrhea in Lanzhou, Gansu province. METHODS: Stool specimens were collected from all 400 inpatients less than 5 years old with acute diarrhea admitted in Department of Pediatrics, the First Hospital, Lanzhou University from Jul. 2004 through Jun. 2005. Dako IDEIA kits were used for detection of rotavirus, adenovirus and astrovirus. Calicivirus detection was done by both reverse transcription-polymerase chain reactions (RT-PCR) and ELISA. Further strain characterization of rotavirus and astrovirus was carried out with RT-PCR. RESULTS: A total of 400 stool samples were collected and tested. Rotavirus was present in 47.3% of the cases: calicivirus in 15.5%, astrovirus in 9.5% and adenoviruses in 7.5%. Mixed infections with multiple enteric viruses were present in 13.5% of all samples. Among 189 rotavirus positive samples, serotype G2 (34.4%) was the predominant strain followed by G3 (32.8%), G1 (1.1%) and mixed-G infection (5.8%). 25.9% of strains remained to be non-typeable. P genotyping showed P [4] (45%) was most common followed by P [8] (22.1%), and non-typeable (32.9%). Strain P [4] G2 (43.6%) was the most common combination followed by P [8] G3 (25.6%), P [4] G3 (13.8%), and P [8] G2, P [4] G1 and P [8] G1. Among 38 astrovirus strains, serotypes 1 (57.8%) was the predominant. Serotype 3 and 8 were found only in one case respectively, 14 strains remained to be non-typeable. A peak admission of rotavirus diarrhea was observed from October through December. More than 95.0% of viral diarrhea patients under hospitalization occurred among children younger than 2 years. The incidence rates of rotavirus were highest in infants aged 6 - 23 months. CONCLUSION: Rotavirus was the most important pathogen for viral diarrhea among children hospitalized in Lanzhou followed by calicivirus, astrovirus, and adenovirus. The predominant rotavirus strain circulated was P [4] G2, which was different from the finding in the previous years. The high rate of mixed infection with different viral agents was notable.

[Molecular epidemiology of human caliciviruses diarrhea among infants and young children in Lanzhou from December 2001 to June 2004].

OBJECTIVE: To investigate the characteristics of human caliciviruses (HuCV) diarrhea among infants and young children with acute diarrhea in Lanzhou, Gansu Province, China by using molecular epidemiologic techniques. METHODS: Stool specimens were collected from both outpatients and inpatients with acute diarrhea in Lanzhou. Enzyme-linked immunosorbant assay (ELISA) was used to detect rotavirus antigen (RVA). Reverse transcription-polymerase chain reactions (RT-PCR) were used to detect HuCV in stool specimens of RV ELISA (-). RESULTS: Of the stool specimens collected from 515 cases in Lanzhou from December 2001 to June 2004, 264 were RVA ELISA (+) and 251 were RVA ELISA (-). Among all cases who were RVA ELISA (-), 25 (9.96%) were found positive for HuCV. HuCV was detected in 12 of 133 cases (9.02%) from December 2001 to November 2002, no genotyping was performed for these cases. From July 2003 to June 2004 13 of 118 cases (11.02%) were found positive for HuCV, of whom 11 cases had Norwalk-like virus GII (NLV GII) infection and 2 cases had Sapporo-like virus infection (one case had combined infection with astrovirus) and no NLV GI was found. HuCV infection mainly occurred in children under 2 years of age and no seasonal cluster was found. CONCLUSION: HuCV is one of the major etiological agents of viral diarrhea among infants and young children in Lanzhou. NLV GII maybe the predominant genotype.

[Rotavirus surveillance data from Kunming Children's Hospital, 1998 - 2001].

OBJECTIVE: To study the epidemiological status on rotavirus diarrhea in Kunming to improve the rotavirus vaccine immunization program. METHODS: A hospital-based sentinel surveillance program for rotavirus was set up among children less than 5 years old with acute diarrhea in Kunming Children's Hospital. Clinical information and fecal specimens were collected and rotavirus were detected by polyacrylamide gel electrophoresis (PAGE) and/or enzyme linked immunosorbent assay (ELISA). Positive specimens were further serotyped or genotyped by ELISA and/or RT-PCR. RESULTS: During the three years of surveillance, 466 specimens were collected. Rotavirus were detected on 246 (52.8%) specimens. 97% of the rotavirus diarrhea cases occurred among children less than 2 years old. There was a peak of admissions for rotavirus diarrhea cases between October and December which accounted for 48% of all the rotavirus hospitalizations each year. Among 204 specimens with G serotyping, the predominant strain was serotype G1 (47.5%) followed by G2 (17.6%), G3 (15.7%), G9 (4.9%) and G4 (1.0%). Mixed infection (2.5%) were rare and 22 specimens (10.8%) remained non-typeable. P genotyping showed P[4], P[8] and P[6] were the most common strains, accounting for 29.3%, 27.6% and 13.8% respectively. P[4]G2 was the most common strain which accounted for 34.1% (14/41) followed by P[8]G1 (29.3%) and P[6]G9 (12.2%). Another 7 uncommon P-G combinations were also identified. CONCLUSION: Rotavirus was the major cause of acute diarrhea in Kunming. An effective rotavirus vaccine for prevention and control of rotavirus diarrhea should be developed.

[Phylogenetic analysis of enterovirus 71 isolated from patients with hand, foot and mouth disease in Guangdong and Fujian provinces, 2000-2001].

OBJECTIVE: To identify enterovirus 71 (EV71) strains isolated from patients with hand, foot and mouth disease (HFMD) in Guangdong and Fujian provinces from 2000 to 2001 by using phylogenetic analysis. METHODS: All 25 samples were first tested for enteric viruses by RT-PCR using enterovirus specific primers EV-1 and EV-2, and then were identified for EV71 by RT-PCR using EV71 specific primers 159S and 162A. The amplicons of 485bp segment (part of the VP1 gene) were cloned into pGEM-T and sequenced. A phylogenetic tree was constructed by comparison of the sequences with other 12 EV71 strains isolated from China, Japan, Hungary, and the United States including the prototype BrCr. RESULTS: The positive rate of EV71 was about 20%. The sequence analysis showed that the new isolate (GZH2000) shared 94%-96% nucleotide identity with three strains isolated in 1998 and 2000, and 91% with a strain isolated in 1987 from Chinese mainland, but shared only 82%-84% homology with EV71 isolates studied abroad. CONCLUSIONS: EV71 is one of the important pathogens of HFMD in south China. The strains isolated from mainland were closely related with most isolates from Taiwan, but different from most EV71 strains reported abroad. The symptoms of EV71 infection in mainland were not as intensive as those described in Taiwan's outbreak.