Simultaneous determination of four flavonoids in Wikstroemia indica by HPLC / 中国中药杂志

The HPLC method was established to simultaneously determine the contents of myricetin, luteolin, apigenin and kaempferol in Wikstroemia indica ( L. ) C. A. Mey. The method was carried out on a Diamonsil C18 column (4. 6 mm x 250 mm, 5 µm) eluted with the mobile phases of water containing 0.15% phosphoric acid and acetonitrile in gradient mode. The UV detection wavelength was 365 nm. The flow rate was 1.0 mL · min(-1) and the column temperature was set at 30 °C. All the standard compounds showed a good linearity in the range of 0.100 8-1.008 (r = 0.999 2), 0.484 8-4.848 (r = 0.999 0) , 1. 354-13. 54 (r = 0.999 6), 0.316 8-3.168 mg · L(-1) (r = 0.999 0) for myricetin, luteolin, apigenin and kaempferol, respectively. The average recoveries of these four flavonoids were 98.5%, 100.9%, 99.7% and 98.9% with RSD 1.2%, 1.7%, 0.81% and 1.6%, respectively. In conclusion, the method is simple, rapid and accurate. It can be applied for the quality control of Wikstroemia indica.

Phylogenetic and Molecular Analysis of an H7N7 Avian Influenza Virus Isolated in East Dongting Lake in 2012 / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>In March 2012, an H7N7 subtype avian influenza virus (AIV) named A/wild goose/Dongting/PC0360/2012 (H7N7) (DT/PC0360) was recovered from a wild goose in East Dongting Lake. We performed whole-genome sequencing of the isolate, and analyzed the phylogenetic and molecular characterization.</p><p><b>METHODS</b>RNA was extracted from environment samples (including fecal samples from wild bird or domestic ducks, and water samples) for detecting the presence of Influenza A Virus targeting Matrix gene, using realtime RT-PCR assay. The positive samples were performed virus isolation with embryonated eggs. The subtype of the isolates were identified by RT-PCR assay with the H1-H16 and N1-N9 primer set. The whole-genome sequencing of isolates were performed. Phylogenetic and molecular characterizations of the eight genes of the isolates were analyzed.</p><p><b>RESULTS</b>Our results suggested that all the eight gene segments of DT/PC0360 belonged to the Eurasian gene pool, and the HA gene were belonged to distinct sublineage with H7N9 AIV which caused outbreaks in Mainland China in 2013. The hemagglutinin cleavage site of HA of DT/PC0360 showed characterization of low pathogenic avian influenza virus.</p><p><b>CONCLUSION</b>Strengthening the surveillance of AIVs of wild waterfowl and poultry in this region is vital for our knowledge of the ecology and mechanism of transmission to prevent an influenza pandemic.</p>

Complete genome phylogenetic analysis of five H9N2 avian influenza viruses isolated from poultry flocks in Qinghai lake region / 病毒学报

Five H9N2 avian influenza virus strains were isolated from the environmental samples in live poultry market in Qinghai Lake region from July to September, 2012. To evaluate the phylogenetic characteristics of these H9N2 isolates, the eight gene segments were amplified by RT-PCR and sequenced. The phylogenetic and molecular characteristics of the five strains were analyzed. The results showed that the HA genes of five strains shared 93. 2%-99. 1% nucleotide identities with each other, and the NA genes shared 94. 5%-99. 8% nucleotide identities. The HA cleavage site sequence of the A/environment/qinghai/ 017/2012 isolate was PSKSSRGLF, and the HA cleavage site sequences of the other four strains were all PSRSSRGLF. The HA receptor-binding site had the Q226L mutation. The M1 gene segment had the N30D and T215A mutations. The phylogenetic analysis showed that the five strains were similar to the virus A/chicken/Hunan/5260/2005 (H9N2) isolated in Hunan Province, China and were reassortant genotype viruses; the HA, NA, and NS genes belonged to the Y280-like lineage; the MP gene belonged to the G1-like lineage; the NP, PB1, PB2, and PA genes belonged to the F98-like lineage.

A novel reassortant H3N8 influenza virus isolated from drinking water for duck in a domestic duck farm in Poyang Lake area / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To conduct a full genome sequence analysis for genetic characterization of an H3N8 influenza virus isolated from drinking water of a domestic duck farm in Poyang Lake area in 2011.</p><p><b>METHODS</b>The virus was cultivated by specific pathogen free (SPF) chicken embryo eggs and was subtyped into hemagglutinin (HA) and neuraminidase (NA) by real-time PCR method. Eight gene segments were sequenced and phylogenetic analysis was conducted.</p><p><b>RESULTS</b>The NA gene of this virus belongs to North American lineage; other seven genes belong to Eurasian lineage. Compared with the viruses containing NA gene, the PB2 and PB1 gene came from different clades. And this indicates that the virus was a novel reassortant genotype. The HA receptor binding preference was avian-like and the cleavage site sequence showed a low pathogenic feature. There was no drug resistance mutation of M2 protein. The mutations of Asn30Asp, and Thr215Ala of the M1 protein implied the potential of pathogenicity increase in mice.</p><p><b>CONCLUSION</b>The finding of novel genotype of H3N8 virus in drinking water in this duck farm near Poyang Lake highlighted the importance of strengthening the surveillance of avian influenza in this region, which could contribute to pinpointing the influenza ecological relations among avian, swine, and human.</p>

Epidemiological characteristics on the clustering nature of pandemic (H1N1) 2009 in China / 中华流行病学杂志

Objective To study the epidemiological characteristics on the clustering nature of pandemic (H1N1) 2009 in China.Methods Time and place distribution of pandemic (H1N1) 2009on the nature of clustering through data from Public Health Emergency Management Information System were described.Results As of August 10,2010,2773 pandemic (H1N1) 2009 clusters,a total of 77363 cases (including 20 deaths) were reported in the mainland of China.The most reported number of clusters was from schools and kindergartens with the total number of 2498 (accounted for 90.08％ of the total number).Middle schools appeared the have the most clusters (1223,accounting for 48.96％ ).The number of clusters reported in the southern provinces (cities) accounted for 77.03％ of the total,and was more than that in the northern provinces (cities).Two reported peaks in the southern provinces (cities) were in June and November,2009,respectively.There was only one reported peakin the northern provinces in September,2009.Conclusion Time and place distribution characteristics on the clusters of pandemic (H1N1) 2009 were similar to the seasonal influenza,but the beginning of winter peak was much earlier and intensity of reporting was much higher on the clusters of pandemic (H1N1 ) 2009 than that of seasonal influenza.

Risk factors for influenza A (H1N1) -associated pneumonia on hospitalized people less than 18years old in China, 2009-2010 / 中华流行病学杂志

Objective To describe the epidemiological and clinical features of hospitalized people less than 18 years old with influenza A (H1N1)-associated pneumonia and associated risk factors.Methods Through Chinese Reporting System of Influenza A (H 1 N1 ),children aged under 18 years who were hospitalized with laboratory confirmed influenza A (H1N1),case report forms and related information on pneumonia were collected between 1 September 2009 and 4 July 2010.Epidemiological and clinical characteristics including demographics,underlying chronic diseases,treatment,complications and clinical outcome etc.were described.Hospitalized children with pneumonia were compared with those without the above mentioned features,through the univariate and multivariate analysis.Results There were 4240 influenza A (H1N1)-associated hospitalized children with case report forms identified.Of the 4107 influenza A (H1N1) -associated hospitalized children with related information on pneumonia shown in the case report forms,2289 (55.7％) of them had pneumonia.Hospitalized children with influenza A (H1N 1 ) -associated pneumonia had a younger median age (4.9year old),when compared with those without pneumonia (13.1 year old,P＜ 0.0001 ).When compared with the hospitalized children without pneumonia,those hospitalized children with pneumonia were more likely to require intensive care unit care,using mechanical ventilation epuipmentto develop ARDS,respiratory failure or leading to death.Data from multivariate analysis showed that children aged ＜6months(OR=7.08,95％CI:4.15-12.06) between 6 and 23 months(aOR=8.26,95％CI:6.10-11.20) or between 2 to 4 year old (aOR=9.53,95％CI:7.39-12.29) were more likely to develop pneumonia than children aged 5 to 17.Factors as having asthma (OR=12.19,95％ CI:5.18-28.72),cardiovascular disease (OR=5.19,95％ CI:1.94-13.90),chronic renal diseases (OR=2.14,95％ CI:1.02-4.53),chronic hepatic diseases ( OR =5.26,95％ CI:1.40-19.81 ) and allergy (OR=2.54,95％ CI:1.64-3.93 )were significantly associated with influenza A (H1N1) -associated pneumonia.Risk of complication with pneumonia had an increase when oseltamivir treatment was initiated ＞2 days after the onset of illness.Conclusion Pneumonia was a common complication among children hospitalized with influenza A (H1N1).Hospitalized children with influenza A (H1N1)-associated pneumonia were more likely to develop either severe clinical courses or outcomes than those without pneumonia.

The virus isolation analysis of the H5N1 subtype human avain influenza cases in mainland China from 2005 to 2009 / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To analyse the correlation between the virus isolation and the specimen collection of the H5N1 human high pathogenic avain influenza cases in Mainland China.</p><p><b>METHODS</b>The specimens were collected in Mainland China from 2005.10 to 2009.3 and the H5N1 viruses were isolated by passage in embryonated chicken eggs.</p><p><b>RESULTS</b>Most specimens were obtained within 14 days after disease onset. For the specimens collected within 7 days, the isolation rate was relatively high and the difference of the positive rate between different years was lower than those specimens collected after 7 days. Most of the samples in our study were collected from the upper or lower respiratory tract with few from blood, feces, et al. The isolation rate of lower respiratory specimens was higher and the difference of the positive rate between different years was relatively lower than those from upper respiratory specimens.</p><p><b>CONCLUSION</b>We suggest that the samples should be collected from lower respiratory tract during the acute phase to get the higher isolation rate.</p>

Spatiotemporal characteristics of seasonal influenza in mainland China / 中华流行病学杂志

Objective To study the spatiotemporal distribution and seasonal characteristics of influenza and to explore its transmission patterns, in the mainland of China. Methods Spatiotemporal cluster methods and spatial trend surface methods were used to analyze the influenza surveillance data. Results There were a summer peak in the south from June to August (RRpsediatric=1.31, P<0.01; RRmternel=1.74, P<0.01) and a winter peak from December to January (RRpsediatric=1.45, P<0.01; RRmternel=1.45, P<0.01) in the northern part of the country, during every epidemic season. Influenza virus in mainland China seemed to spread from the southern to the northern parts of the country, in a progressing way. Conclusion In the southern part of the country, it is more important to take prevention and control measurements on influenza from June to August but for the northern part, the key period is from December to January. It is more important to timely identify the variation of the influenza virus, in the southern part of the country.

Comprehensive evaluation on the potential risk for HIV infection in 12 villages with a history of former paid blood donation / 中华流行病学杂志

<p><b>OBJECTIVE</b>To learn the potential risk for human immunodeficiency virus (HIV) infection in 12 villages with a history of former paid blood donation, and to provide different measures for HIV/AIDS prevention and control.</p><p><b>METHODS</b>Seven indexes were selected, including HIV sero-prevalence rates, hepatitis C virus (HCV) sero-prevalence rates, HIV/AIDS KAB (knowledge, attitude and belief), proportion of paid blood/plasma donation, risks on related behavioral information on sex and HIV/AIDS infections. Rank Sum Ratio (RSR) was performed to synthetically evaluate the potential risk of HIV infection in those 12 selected villages.</p><p><b>RESULTS</b>According to the results of evaluation by 18 experts, weight coefficient of HIV sero-prevalence rate was the highest (0.28), and HIV/AIDS KAB the lowest (0.09) among the seven indexes. The results of comprehensive evaluation with RSR showed that the villages coded 01 and 02 belonged to higher level of potential risk of HIV infection, villages 09, 12, 05, 10 and 03 were at medium level while villages 04, 06, 08, 07 and 11 were at low level.</p><p><b>CONCLUSION</b>The level of potential risk for HIV infection was different in 12 villages with a history of former paid blood donation. Different measures of HIV/AIDS prevision and control should be performed according to the potential risk level for HIV infection of the 12 villages.</p>

Antigenic and genetic study of influenza virus B circulated in China in 2004-2005 / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To analyze the genetic and antigenic characteristics of hemagglutinin (HA) gene of human influenza B virus isolated from the mainland of China since 2004-2005.</p><p><b>METHODS</b>The single-way hemagglutinin inhibition (HI) tests were used to test the antigenic characteristics, and the HA1 gene was sequenced based on the antigenic results.</p><p><b>RESULTS</b>The Yamagata-like and Victoria-like viruses co-circulated in 2004-2005. For the Yamagata-like virus, the single-way HI results showed that 3.7% and 4.5% of the viruses had 4-fold greater HI titer difference compared with B/Shanghai/361/02 in 2004 and 2005, respectively. The HA1 sequence data showed that the virus had amino acid mutation, and there was one more glycosylation site at 196th site. For the Victoria-like virus, the single-way HI results showed that 8.5% and 20.6% of the viruses had 4-fold greater HI titer difference compared with B/Hong kong/330/01 in 2004 and 2005, respectively. The HA1 sequence data showed that the virus had replacement of 9 amino acids, and there was one more glycosylation site at 197th site.</p><p><b>CONCLUSION</b>The results showed that influenza B viruses had changed antigenic and genetic characteristics compared with B/Shanghai/361/02, B/Hong kong/330/01 in 2004-2005.</p>

Laboratory diagnoses of the first confirmed human case of avian influenza A (H5N1) in the mainland of China / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To determine the etiologic agent of an atypical pneumonia human case admitted to Xiangtan City hospital, Hunan Province in Oct. 2005.</p><p><b>METHODS</b>The patient's respiratory tract samples and serum were collected. Throat swabs were tested by microneutralization and hemagglutination-inhibition assays.</p><p><b>RESULTS</b>The results of nucleic acid detection of all respiratory samples were negative and virus isolation was also negative. The H5-specific antibodies of convalescence showed a 4-fold greater rise than acute phase.</p><p><b>CONCLUSION</b>The atypical pneumonias case was confirmed as the first human case of avian influenza A (H5N1) infection in the mainland of China.</p>

Antigenic and genetic study of influenza virus (H1N1) circulated in China in 2004-2005 / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To analyze the genetic and antigenic characteristics of hemagglutinin (HA) gene of human influenza (H1N1) virus isolated from the mainland of China since 2004 to 2005.</p><p><b>METHODS</b>The single-way hemagglutination inhibition (HI) tests were used to test the antigenic characteristics, and the HA1 gene was sequenced based on the antigenic results.</p><p><b>RESULTS</b>The single-way HI results showed that no virus isolates had 4-folds greater HI titer compared with A/Shanghai/1/1999 (H1N1) in 2004, but there was 6.3% virus had 4-fold greater difference in 2005. The HA1 sequence data showed that the H1N1 virus had the following amino acid mutations such as 54 K > R, 90 T > K, 101 Y > H, 149 R > K, 169 V > A, 190 D > N, 212 R > K, 219 K > R, 245 W > R, 246 Y > F, 258 T > N, 318 V > A and the 54 and 190 amino acids located in antigenic group of HA1.</p><p><b>CONCLUSION</b>The H1N1 virus was changing in antigenic and genetic characteristics.</p>

The first confirmed human case of avian influenza A (H5N1) in mainland, China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To ascertain the causation of a family cluster involving two undefined pneumonia cases, a 12-year-old girl and her brother, reported October, 2005 in Xiangtan county, Hunan province.</p><p><b>METHODS</b>Information on epidemiology and clinical manifestation of the cases was collected from interviewing the keyman and referring to related medical records. The environment exposure of the cases to their households and the timeline of the illness were reproduced, using this information. Medical check-up was undergone among the close contacts of the cases and on sick/dead poultry. Throat swab of the cases were collected and tested by both RT-PCR and real-time PCR to detect viral nucleic acids of A/H5N1, and were then inoculated into special pathogen free (SPF) embryonated hens' eggs. Serum of the cases including acute and convalescent phases were also collected and tested by microneutralization and haemagglutination-inhibition (HI) assays to detect H5-specific antibodies.</p><p><b>RESULTS</b>Both the girl and her brother developed fever 2 and 4 days after sudden deaths of chickens being raised in the same house. Both of them had developed pneumonia and the girl died from acute respiratory distress syndrome (ARDS) complicated with multi-organ failure. The boy survived and subsequently discharged from hospital. An eighth-day serum from the girl tested H5 antibody negative, while 4-fold and greater increased in antibody titers were detected in serum from the boy using microneutralization and HI assays in sequential acute and convalescent sera. Of 192 cases, only one doctor who cared for the girl during hospitalization had upper respiratory symptoms but tested negative for H5N1 by microneutralization assay.</p><p><b>CONCLUSION</b>The boy was the first confirmed human case of avian influenza A (H5N1) in the mainland of China and his sister was diagnosed clinically. The most probable explanation of these two cases was that the transmission of H5N1 virus from infected poultry within the same household environment. No evidence of human-to-human transmission was noted in the family cluster.</p>

Study on a fatal pregnant woman died from by avian influenza (H5N1) / 中华流行病学杂志

<p><b>OBJECTIVE</b>To ascertain the causation of a pregnant woman with undefined pneumonia reported from the People's Hospital of Tongling city in Anhui province on November 2005.</p><p><b>METHODS</b>Epidemiological and clinical information of the case was collected from the keypersons close to the case and referring to the medical record. A medical observation was carried out on the close contacts of the case and sick or dead poultry. Tracheal aspirates being collected were tested by both RT-PCR and real-time PCR to detect viral nucleic acids of A/H5N1, and were inoculated into special pathogen free (SPF) embryonated hens' eggs.</p><p><b>RESULTS</b>The pregnant woman was found to have been contacted with the sick/dead poultry directly on the 4th day before onset of illness. All the 122 close contacts were healthy after a 10-day medical observation. The major clinical features of the case were viral pneumonia with rapidly developed leukopenia and lymphopenia. The progress to acute respiratory distress syndrome and multiple organ dysfunction syndromes was found at clinical presentation. HA and NA gene of A/H5N1 virus were positive. The 8 gene fragments of A/Anhui/1/2005 (H5N1) isolated from the tracheal aspirates had not carried genes from a human virus through reassortment, and the receptor-binding site of the hemagglutinin was polybasic cleavage site.</p><p><b>CONCLUSION</b>This was the first documented case of H5N1 infection in pregnant woman. The immunotolerant state of pregnancy might have predisposed to the fatal outcome of the patient.</p>