Applicability of three surveillance methods for Aedes albopictus in dengue risk indication / 中华疾病控制杂志

Objective To disscus the applicability of three surveillance methods for Aedes albopictus in dengue risk indication. Methods Larval and adult mosquito surveillance were conducted in two villages of Guangzhou by using three vector monitoring methods. Meteorological data and dengue cases were obtained in the same period. Results The population dynamics of larvae and adult mosquitoes were affected by temperature and their overall trend was consistent, but there were differences between the abundance of larvae and adult mosquitoes. From December to February the next year, Breteau index(BI) ranged from 5.66 to 24.53 with a risk of level 1 to 3 for dengue fever, while the mosquito and oviposition positive index(MOI) and adult-mosquito density index(ADI) were 0 to 4.00 and 0 to 1 per man-hour, respectively, indicating no risk for dengue fever. In March, compared with BI which indicated a risk of level 3, MOI were 2.13 and 3.77, respectively, representing for no risk. ADI were 4 to 6 per man-hour, indicating a risk of level 1 and level 2, respectively. After April, the dengue risk level reflected by each indicator became to be consistent. Conclusions The risk of dengue fever indicated by BI is always higher than or equal to the risk indicated by the other two. Compared with BI, MOI and ADI are more sensitively in reflecting the activity of Ae. albopictus.

Inhibitory effect of resveratrol against enterovirus type 71 in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the inhibitory effect of resveratrol against the cytopathogenicity of enterovirus type 71.</p><p><b>METHODS</b>The cytotoxicity of resveratrol on Vero cells was detected using cell counting kit-8 (CCK-8). The antiviral activity of resveratrol in different stages of infection, with ribavirin as the control, was evaluated by determining the virus inhibition rate, medium effective concentration (IC(50)), and selection index (SI).</p><p><b>RESULTS</b>Resveratrol was nonpoisonous to Vero cells with an median toxic concentration (TC50) of 307.6 mmol/L. Resveratrol produced an obvious inhibitory effect against enterovirus type 71 only before the cell infection by the virus (IC(50)=20.2 mmol/L , SI=15.2), and once the cells were infected, resveratrol no longer had such antiviral effect.</p><p><b>CONCLUSIONS</b>Resveratrol may offer some protection against enterovirus type 71 in vitro.</p>

Association of CCR5, CCR2 and SDF1 gene polymorphisms with HIV-1 infection in Chinese population: a meta-analysis / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the association of CCR5δ32, CCR2-64I and SDFl-3 A gene polymorphisms with HIV-1-infection in Chinese population.</p><p><b>METHODS</b>A meta-analysis was performed to identify case-control studies of CCR5δ32, CCR2-64I and SDFl-3 A polymorphisms from the literatures.</p><p><b>RESULTS</b>Fourteen studies of CCR5δ32 were found, involving a total of 1607 cases and 1632 controls. Compared with the wild-type homozygote wt/wt, the pooled odds ratios (95%CI) of wt/mt, mt/mt, and wt/mt+mt/mt genotypes of CCR5δ32 gene polymorphisms were 1.156 (0.808, 1.654), 0.997 (0.198, 5.022), and 1.149 (0.808, 1.634), respectively. Twelve studies of CCR2-64I were identified, including 1415 cases and 1239 controls. Compared with the wild-type homozygote wt/wt, the pooled odds ratios (95%CI) of wt/mt, mt/mt, and wt/mt+mt/mt genotypes of CCR2-64I gene polymorphisms were 1.005 (0.844, 1.197), 1.191 (0.808, 1.754), and 1.028 (0.870, 1.214), respectively. Ten studies of SDFl-3 A were found, involving 1179 cases and 1003 controls. Compared with the wild-type homozygote wt/wt, the pooled odds ratios (95%CI) of wt/mt, mt/mt, and wt/mt + mt/mt genotypes of SDF1-3 A gene polymorphisms were 1.010 (0.830, 1.228), 1.188 (0.860, 1.643), and 1.038 (0.861, 1.250).</p><p><b>CONCLUSION</b>CCR5δ32, CCR2-64I and SDFl-3 A gene polymorphisms do not show strong correlations to HIV-1-infection in Chinese population. These 3 genes may not have protective effect against HIV-1 infection in Chinese population, suggesting the susceptibility of Chinese population to the infection.</p>

Detection and genotype analysis of sapovirus associated with sporadic diarrhea in Shenzhen in 2009 / 南方医科大学学报

<p><b>OBJECTIVE</b>To conduct an epidemiological and genotype analysis of sapovirus (SaV) associated with sporadic diarrhea in Shenzhen in the year 2009.</p><p><b>METHODS</b>A total of 852 fecal samples were collected from sporadic cases of diarrhea in Shenzhen in 2009 and detected by reverse-transcription polymerase chain reaction (RT-PCR) using the primers of SLV5317/5749. The PCR products were analyzed with 1.5% agarose gel electrophoresis and sequenced to construct the phylogenetic tree.</p><p><b>RESULTS</b>Sixteen samples were found positive for SaV, with a positivity rate of 1.88%. Sequence analysis identified 8 isolates as SaV GI genotype (including 3 SaV GI.1 and 5 SaV GI.2), 7 as SaV GIV genotype, and 1 as GII genotype.</p><p><b>CONCLUSIONS</b>SaV infection is present in Shenzhen with GI as the predominant genotype. This is the first report of SaV GIV strains in China, which differs from the strains of Anhui-A141 and Beijing-CHN99/BJ360, suggesting the genotypic variety of SaV infection in China.</p>

Protective effects of resveratrol on lipopolysaccharide-induced inflammatory toxicity in primary cortical astrocyte cultures / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the anti-inflammatory effect of resveratrol in primary cortical astrocyte cultures stimulated by lipopolysaccharide (LPS) and explore the underlying mechanism of this protective effect.</p><p><b>METHODS</b>The astrocytes were cultured in the presence of resveratrol at different concentrations for 12 h followed by stimulation with lipopolysaccharide (LPS) for another 24 h. Lactate dehydrogenas (LDH) leakage volumes were detected, the cytotoxicity of resveratrol was examined using cell counting kit-8 (CCK-8), the release of NO was measured by Griess reaction, and the expression levels of TNF-α and iNOS were measured using ELISA and Western blotting respectively.</p><p><b>RESULTS</b>The purity of the astrocytes cultured in vitro was (95.49∓1.86)%. LPS treatment increased LDH leakage and reduced the survival rate of the astrocytes, resulting also in significantly increased NO and TNF-α release and iNOS protein expressions. Within the concentration range of 5-50 µmol/L, resveratrol effectively improved the survival rate of the astrocytes and decreased LDH leakage with a dose-response relationship. Only 25 and 50 µmol/L resveratrol produced obvious inhibitory effect on NO and TNF-α release and iNOS expression, while 5 µmol/L resveratrol had no such effects.</p><p><b>CONCLUSION</b>High concentration of resveratrol can inhibit the release of inflammatory mediators and improve the inflammation injury induced by LPS in astrocytes, the mechanism of which may involve the inhibition of iNOS/NO expression pathway.</p>

Prevalence and antimicrobial susceptibility of Laribacter hongkongensis and enterotoxigenic Escherichia coli isolated from patients with diarrhea in Guangzhou / 南方医科大学学报

<p><b>OBJECTIVE</b>To survey the prevalence of enterotoxigenic Escherichia coli (ETEC) and Laribacter hongkongensis (LH) and their drug resistance in diarrhea patients in Guangzhou.</p><p><b>METHODS</b>We detected 646 fecal cases collected between Sep 2008 and Oct 2009 from the out-patient and emergency departments in a hospital. EC enriched culture medium was used for enrichment. MAC- and CMAC-specific culture media were used to isolate ETEC and LH from the specimens. The biochemical agents API20NE and API20E were employed for biochemical identification, and PCR was used for genetic identification. K-B disk diffusion method was used for antimicrobial susceptibility testing.</p><p><b>RESULTS</b>No LH was detected in the total 646 patients, and 38 patients were positive for ETEC, with a detection rate of 6%. Antibiotics resistance test showed that 38 strains of ETEC had a high resistance rate to penicillin, tetracycline and sulfa, but remained sensitive to cephalosporins.</p><p><b>CONCLUSIONS</b>LH may have a low prevalence in Guangzhou. The incidence of diarrhea caused by ETEC tends to decrease as compared with that a decade ago, and further multi-center survey is needed for confirmation. Consumption of aquatic products may be one of the major risk factors for ETEC infection. Cephalosporins can be used for ETEC-induced diarrhea.</p>

Computer-assisted screening system for individualized treatment of type 2 diabetes mellitus / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a computer-assisted screening system for individualized treatment of type 2 diabetes mellitus.</p><p><b>METHODS</b>The clinical data of the diabetic patients were retrospectively analyzed, and the regression equation for the affecting factors and therapeutic effect was established. With computer-aided programming, a computer-assisted screening system was established.</p><p><b>RESULTS</b>A computer-assisted screening system for individualized treatment type 2 diabetes was established, which showed a concordance rate was 98% in clinical verification.</p><p><b>CONCLUSION</b>Using epidemiological methods and assistance by computer technique, a computer-assisted screening system for individualized prescription can be established for selecting therapeutic regimen for type 2 diabetes.</p>

An analysis of the characteristics and etiology of hand, foot and mouth disease in a Guangzhou sentinel hospital from May to December, 2008 / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze the characteristics and etiology of hand, foot and mouth disease (HFMD) in a sentinel hospital of Guangzhou.</p><p><b>METHODS</b>The epidemiological data and clinical specimens were collected from May to December, 2008 for virological investigations (viral isolation, RT-PCR and molecular identification) and phylogenetic analysis.</p><p><b>RESULTS</b>A total of 309 clinical cases were reported, and the incidence was the highest in 2-4-year-old children, among whom only 15 developed complications, with human enterovirus 71 (HEV71) as the main pathogen (64.7%). Phylogenetic analysis indicated that ten Guangzhou EV71 isolates belonged to Cluster C4a.</p><p><b>CONCLUSION</b>HFMD is an important infectious disease in children resulting from infections by HEV71 as the main pathogen in 2008, and the Guangzhou C4a strains co-evolved with the isolates from other provinces in China and the neighboring countries.</p>

Establishment of an artificial neural network model for analysis of the influence of climate factors on the density of Aedes albopictus / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a model for predicting the density of Aedes albopictus based on the climate factors.</p><p><b>METHODS</b>The data of Aedes albopictus density and climate changes from 1995 to 2001 in Guangzhou were collected and analyzed. The predicting model for Aedes albopictus density was established using the Artificial Neural Network Toolbox of Matlab 7.0 software package. The climate factors used to establish the model included the average monthly pressure, evaporation capacity, relative humidity, sunshine hour, temperature, wind speed, and precipitation, and the established model was tested and verified.</p><p><b>RESULTS</b>The BP network model was established according to data of mosquito density and climate factors. After training the neural network for 25 times, the error of performance decreased from 0.305 539 to 2.937 51x10(-14). Verification of the model with the data of mosquito density showed a concordance rate of prediction of 80%.</p><p><b>CONCLUSION</b>The neural network model based on the climate factors is effective for predicting Aedes albopictus density.</p>

Application of Excel programs of Fisher exact probability test for medical data / 南方医科大学学报

<p><b>OBJECTIVE</b>To accomplish the computation of Fisher exact probability test for fourfold table data in Excel.</p><p><b>METHOD</b>The computing program of exact probability method for medical data in fourfold table design was edited by employing the IF statement and the relevant functions, such as SUM, FACT, DSUM, etc in Excel. The computational results are compared and evaluated according to the case studies.</p><p><b>RESULTS</b>The output of Fisher Exact Probability was generated and presented correctly following the input of four numerical values into the computation program in the setting of Excel. The parametric outcomes are in agreement with those produced by SAS and SPSS, in the combination tables containing the P value, two-tailed cumulative P value, left-tailed P-value, right-tailed P-value, Chi2 values and P values both for direct Chi-squared test and corrected Chi-squared test.</p><p><b>CONCLUSIONS</b>Direct Chi-squared test, corrected Chi-squared test combined with Fisher Exact Probability test for fourfold table data can be conveniently, rapidly, and accurately accomplished in Excel.</p>

Antimicrobial resistance of clinical isolates of Stenotrophomonas maltophilia / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the antimicrobial resistance of clinical isolates of Stenotrophomonas matophilia (SMA) and the mechanisms of their drug resistance.</p><p><b>METHODS</b>Disc diffusion method (NCCLS) was used to detect the resistant patterns of 88 initial SMA isolates resistant to 12 antibiotics isolated from a local hospital in the past 4 years. PCR was used to detect the 7 aminoglycosides modifying enzymes genes (AME) against amikacin and gentamicin. Metal-beta-lactamases (MBLs) were screened by synergic method, and extended-spectrum beta-lactamases (ESBLs) were detected by double-disk synergy test.</p><p><b>RESULTS</b>The resistance rates of the SMA isolates were 0%-9.7% to minocycline, 12.5%-22.6% to ticarcillin-clavulanic acid, 12.5%-28.6% to levofloxacin, 18.8%-33.3% to doxycycline, 18.8%-40% to sulfamethoxazole compound, 50%-65.7% to ciprofloxacin, 50%-66.7% to cehazindme, 54.8%-66.7% to amikacin, 75%-100% to gentamicin, 81.3%-100% to piperacillin, 87.5%-100% to aztreonam and 93.5%-100% to imipenem. Aac(3)-I and ant(4')-II were not detected in these strains. The positive rates of the other 5 AME genes of aac(3)-II, ant(2'')-I, aac(6')-I, aac(3)-III, aac(3)-IV were 2.3%, 5.7%, 8%, 10%, and 10%, respectively. SMA strains producing ESBLs were found at the rate of 38.6%; 25% of the strains were MBL-producing, and 13.6% produced both ESBLs and MBLs.</p><p><b>CONCLUSION</b>Most of the SMAs we isolated are multidrug-resistant through various mechanisms. The choice of antibiotics should be made according to the susceptibility results.</p>

Development of the lung cancer diagnostic system / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop a lung cancer diagnosis system.</p><p><b>METHODS</b>A retrospective analysis was conducted in 1883 patients with primary lung cancer or benign pulmonary diseases (pneumonia, tuberculosis, or pneumonia pseudotumor). SPSS11.5 software was used for data processing. For the relevant factors, a non-factor Logistic regression analysis was used followed by establishment of the regression model. Microsoft Visual Studio 2005 system development platform and VB.Net corresponding language were used to develop the lung cancer diagnosis system.</p><p><b>RESULTS</b>The non-factor multi-factor regression model showed a goodness-of-fit (R2) of the model of 0.806, with a diagnostic accuracy for benign lung diseases of 92.8%, a diagnostic accuracy for lung cancer of 89.0%, and an overall accuracy of 90.8%.</p><p><b>CONCLUSION</b>The model system for early clinical diagnosis of lung cancer has been established.</p>

Identification and genotyping of oncogenic type of human papillomavirus in paraffin-embedded cervical cancer samples in Guangzhou / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate human papillomavirus (HPV) infection and genotyping in patients with cervical cancer in Guangzhou in the last 3 decades.</p><p><b>METHODS</b>HPV L1 gene fragment in paraffin-embedded cervical cancer samples was amplified by HPV-specific PCR with consensus primers, and typing of HPV strains was performed on the basis of sequence analysis of the PCR products.</p><p><b>RESULTS</b>The positivity rates of HPV DNA was 26.2% in the 99 cases of cervical cancer. Five HPV genotypes were identified including HPV16, 18, 33, 52 and 58.</p><p><b>CONCLUSION</b>HPV16, 58 and 33 are the most common genotypes of HPV, accounting for over 88.4% in the total infected cases, suggesting that the HPV genotypes closely related to cervical cancer is more centralized in Guangzhou.</p>

Polymorphisms of human papillomavirus type 81 L1 gene in patients with cervical lesions in Guangdong / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the positivity rates and genetic polymorphism of human papillomavirus (HPV) type 81 (HPV81) L1 gene in patients with cervical cancer in Guangdong.</p><p><b>METHODS</b>HPV L1 genes fragment in 1200 positive cervical samples detected with HC-II for high-risk HPV DNA were amplified by HPV-specific PCR with consensus primers, and the L1 genes of HPV81 were sequenced for mutation analysis.</p><p><b>RESULTS</b>Four HPV81-positive cases were found in the total of 1200 cases for the positivity rate of 0.33%. Point mutations of HPV81 L1 gene were found in all of the samples.</p><p><b>CONCLUSION</b>Compared with the HPV81 prototypes published in GenBank, several new point mutations are found in the L1 genes of the HPV81 in Guangdong, and these mutations are close to those found in Japan.</p>

Effects of resveratrol on the release of Glu and Gln in cultured rat astrocytes with stretch injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effects of resveratrol on amino acid release in cultured astrocytes with stretch injury and explore its possible mechanism for central nervous system protection.</p><p><b>METHODS</b>Cultured rat astrocytes were treated with different concentrations of resveratrol for 12 h and the subsequent changes in Glu and Gln release and lactate dehydrogenase(LDH) leakage were examined after stretch injury.</p><p><b>RESULTS</b>High-performance liquid chromatography showed that stretch injury increased Glu release from the astrocytes (P<0.05), and at the concentration of 1 micromol/L, resveratrol further increased Glu release (P<0.05), whereas at 100 micromol/L, resveratrol obviously inhibit Glu release (P<0.05). LDH leakage increased significantly after stretch injury of the astrocytes (P<0.05), and resveratrol acted to further increase LDH leakage at 1 micromol/L but inhibited LDH leakage at 100 micromol/L (P<0.05).</p><p><b>CONCLUSION</b>Resveratrol can inhibit the release of Glu and LDH leakage from rat astrocytes to protect the cells from stretch injury.</p>

Ureaplasma urealyticum infection in the genital tract reduces seminal quality in infertile men / 中华男科学杂志

<p><b>OBJECTIVE</b>To understand Ureaplasma urealyticum (Uu) infection, analyzed the influence of Uu infection on the seminal quality and the accessory genetical gland function in male infertility patients, and investigate its mechanism.</p><p><b>METHODS</b>We cultured 202 semen samples collected from male infertility patients and analyzed the influence of Uu infection on seminal parameters and the biochemical indexes of the seminal plasma.</p><p><b>RESULTS</b>The Uu infection rate was 33.7% in the infertile males, with no statistic differences between the Uu positive and negative groups either in the average age (28.9 +/- 4.7 yrs vs 29.6 +/- 4.0 yrs, P = 0.250) or in the seminal quantity (2.93 +/- 1.32 ml vs 2.86 +/- 1.52 ml, P = 0.774). The sperm density, motility and vitality were (84.37 +/- 52.92) x 10(6) ml, (44.62 +/-22.13) % and (38.40 +/- 15.61) % in the Uu positive group, significantly lower than (101.90 +/- 43.90) x 10(6) ml, (51.83 +/- 19.88) % and (44.45 +/- 15.47) % in the Uu negative group (P = 0.025, P = 0.036 and P = 0.020). The seminal pH value was normal in both of the groups, but significantly higher in the Uu positive than in the negative group (7.32 +/- 0.10 vs 7.19 +/- 0.29, P = 0.003). VCL, VSL, VAP and MAD were significantly lower, while BCF was significant higher in the former than in the latter [(33.97 +/- 8.96) microm/s vs (39.70 +/- 8.14) microm/s, t = 4.113, P < 0.001; (22.29 +/- 6.06) microm/s vs (25.20 +/- 6.67) microm/s, t = 2.684, P = 0.008; (25.96 +/- 6.83) microm/s vs (30.02 +/- 6.81) microm/s, t = 3.537, P < 0.001; 46.60 +/- 13.68 vs 54.23 +/- 15.14, t = 3.112, P = 0.002; (6.12 +/- 1.89) Hz vs (5.22 +/- 1.64) Hz, t = 3. 164, P = 0.002]. All the five indexes were influenced by Uu infection. Compared with the negative group, the seminal plasma alpha-glucosidase was significantly decreased in the positive group [(40.0 +/-18.7) U/ml vs (47.9 +/- 21.0) U/ml, t = 2.248, P = 0.026], and the risk of the decrease was 2.12 times higher. No statistic difference was observed in seminal plasma acid phosphatase and seminal plasma fructose between the two groups.</p><p><b>CONCLUSION</b>Uu infection in the genital tract is an important factor of seminal quality reduction in infertile men and may cause a decreased secretion of alpha-glucosidase in the epididymis, but it hardly influences the prostate and seminal vesicle.</p>

Development of a SPA-ELISA method for detecting anti-coronavirus IgG antibodies in serum samples from fulvous fruit bats / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop an simple and sensitive method for detecting anti-coronavirus IgG antibodies in bat sera based on enzyme-linked immunosorbent assay (ELISA).</p><p><b>METHODS</b>A commercial ELISA kit for detecting SARS-CoV antibody was modified for detecting coronavirus antibodies in bat serum samples. The second antibody in the kit was replaced with horseradish peroxidase-conjugated protein-A (HRP-SPA) based on the characteristics of binding between Staphylococcus aureus protein A (SPA) and mammal IgG Fc fragment. The sera of 55 fulvous fruit bats (Rousettus dasymallus) were tested using the SPA-ELISA.</p><p><b>RESULTS</b>The test results of the positive and negative controls in the kit and the serum samples from convalescent ;patient were consistent with expectation. Coronavirus antibody was detected in 2 out of the 55 bat serum samples. Serum neutralization test confirmed the validity of the SPA-ELISA method.</p><p><b>CONCLUSION</b>This SPA-ELISA method is applicable for detecting coronavirus antibody in bat sera.</p>

Effect of Fructus Bruceae oil emulsion on cellular immune function and quality of life in patients with non-small cell lung cancer / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of Fructus Bruceae oil emulsion (FBE) on cellular immune function (CIF) and quality of life (QOF) in patients with non-small cell lung cancer (NSCLC) after chemotherapy.</p><p><b>METHODS</b>One hundred and fifteen patients with mid-late stage NSCLC were randomly assigned to two groups, the 57 patients in the control group were only treated with chemotherapy of GP regimen, 58 in the treatment group with the chemotherapy of the same regimen and combined with FBE. The clinical efficacy was evaluated after two cycles of chemotherapy.</p><p><b>RESULTS</b>The effective rate was 51.8% and 47.4% in the treatment group and the control group respectively, the difference between them was insignificant (P > 0.05). CIF and QOF in the treatment group were better than those in the control group after chemotherapy respectively (P < 0.01), in the latter, CIF and QOF were desreased after chemotherapy (P < 0.05).</p><p><b>CONCLUSION</b>FBE combined with chemotherapy can improve the cellular immune function and quality of life in patients with mid-late stage NSCLC.</p>

Comparison of mental health state and psychological capacities between college students with and without siblings / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the differences in mental health state and psychological capacities between Chinese college students with and without siblings.</p><p><b>METHODS</b>The psychological status and capacities were evaluated with SCL-90, the Self-Esteem Scale, Spheres of Control Scale, Security Questionnaire and Cattell 16-PF Questionnaire in 427 college students, and among the students who presented valid responses, 139 with and 139 without siblings were selected for this comparative study.</p><p><b>RESULTS</b>The total score and average score of SCL-90 in college students without siblings were significantly lower than those in students with siblings (P<0.05); the scores of factors C, E, and F of 16-PF were significantly higher but the score of factor O significantly lower in the former group (P<0.05). The scores of certainty in control, interpersonal security and total score of security were significantly higher in the students without siblings (P<0.01).</p><p><b>CONCLUSION</b>The mental health state and some of the psychological capacities are generally better in college students with siblings than in those without siblings.</p>

Characteristics, evolution and variation of M genes of human avian H5N1 strains in Guangdong / 病毒学报

In order to reveal variation and evolution of M genes of human avian H5N1 influenza strains, the M genes of human avian H5N1 strains in Guangdong were sequenced and the M genes of global strains were searched out from Internet. They were analyzed by DNAStar 5. 0 and their revolutionary speeds were studied by means of combining the epidemiological data. It was found that M1 genes of 53 H5N1 strains and M2 genes of 51 strains during 1997-2006 were homologously classified into two groups: the strains from Hong Kong during 1997 (G I) were one group and the strains from Hong Kong, Vietnam, Thailand, Indonesia, China mainland, Turkey, Iraq, Azerbaijan, Egypt during 2003-2006 (G II ) were the another group. There were 20 substitutions of amino acids in M1 gene of all strains (7.94%, 20/252), where there were 9 amino acids in strains during 2003-2006 differing from the strains in 1997, meanwhile there were 22 substitutions of amino acids in M2 gene of all strains (22.7%, 22/97), where there were 4 amino acids in strains during 2003-2006 differing from the strains in 1997. In the synonymous variation, Ks values in M1 were 26.8 x 10(-6)-42.6 x 10(-6) Nt/d, and Ka values 4.39 x 10(-6)-6.98 x 10(-6) Nt/d, where there was more rapid speed of synonymous substitution than that of replacement, which showed that there existed less human immunological pressure and negative selective pressure by biological test. Ks values in M2 were 13.1 x 10(-6)-23.4 x 10(-6) Nt/ d, and Ka values 9.1 x 10(-6)-16.2 x 10(-6) Nt/d; where the ratios of Ks to Ka was 1.0-1.6 times as there was the neutral selective pressure in TL-676-05 strain. There was an amino acid substitution of S224, N in M1 gene of strains during 2003-2006 and an increas in a glycoprotein domain NSS224-226. The secondary structure of M2 protein varied as the substitution of C50 F of eight strains from Indonesia in 2005. The strains G I did not reemerge after Hong Kong human avian H5N1 influenza event. An increase of a glycoprotein domain NSS224-226 in M1 protein during 2003-2006 might be related with virus pathogenicity. Human avian H5N1 influenza M gene evolved frequently in nature, which might have an impact on its capacity of human-to-human transmission.