Entamoeba is a zoonotic protozoan that can parasitize in the intestine and other organs in human and animals . There are many species in this genus ,but only Entamoeba histolytica can cause amebic colitis and liver abscess ,and even death .The cysts and trophozoits are difficult to be discriminated for pathogenic and nonpathogenic Entamoeba .And there is al-so difference in the pathogenicity ,infectivity etc .,even in the same species .Therefore ,it is difficult to confirm the Entamoeba species according to traditional method ,thus affecting the use of medicine .In this article ,the research progress of molecular examination and genotyping method about entamoeba are reviewed .

Associations between "lipid-related" candidate genes, blood lipid concentrations and coronary artery disease (CHD) risk are not clear. We aimed to investigate the effect of three newly identified lipids loci from genome-wide association studies on CHD and blood lipid levels in Chinese Han population. The genotypes of SNPs at three newly identified lipid loci and blood lipids concentrations were examined in 1360 CHD patients and 1360 age- and sex-frequency matched controls from an unrelated Chinese Han population. Allele T of rs16996148 occurred less frequently in CHD patients with the odds ratio (OR) being 0.64 (95% CI 0.50 to 0.81), after adjusting for conventional risk factors and was associated with a 33% decreased CHD risk (P<0.01) comparing with the major allele G. Individuals with GT genotype had the lowest CHD risk. No associations were found between the polymorphisms of other two loci with CHD risk and all three SNPs had no effect on lipid profile in this population. SNP rs16996148 on chromosome 19p13 is significantly associated with lower risk for CHD in Chinese Han population. However, it remains unresolved why these lipid-related loci had significantly less effects than the correspondingly expected effects on blood lipids levels in this population.

The association between atrial natriuretic peptide (ANP) polymorphism and coronary heart disease (CHD) was studied in Chinese population. The genotypes of ANP T2238C and ANP C-664G were detected by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) methods in 158 consecutive CHD patients and 165 controls. It was found that the distribution of A2A2 genotype in CHD group was significantly higher than that in control group (P<0.05). Stepwise Logistic regression analysis revealed that male, smoking, history of hypertension, history of diabetes, family history of hypertension, high level of serum cholesterol, and ANP T2238C polymorphism were the possible risk factors in patients with CHD (P<0.05). However, there was no significant difference between the patients with CHD and the control group in the distribution of ANP C-664G polymorphism (P>0.05). The results suggest that A2A2 T2238C genotype could be one of the risk factors for CHD (P<0.05, OR: 1.80, 95 % CI: 1.03-3.15).

Objective To investigate the rs501120 and rs17465637 gene polymorphisms,and their relationship with the risk of coronary heart disease(CHD)in Chinese Han population.Methods 775 CHD without treatment and 775 age and gender matched controls were selected for this study,the genotypes of two single nucleotide polymorphisms(SNP)rs501120 and rs17465637 were tested with TaqMan-MGB probes.Results There was no significant difference in the frequency of genotypes of the 2 SNPs between CHD group and control group(P ＞0.05).Stratified analysis showed that SNP rs501120 had significant protection with CHD in people younger than 60 years old(OR 0.4,95% CI 0.2-0.9,P ＜ 0.05)or people with diabetes(OR0.3,95%CI0.1-0.7,P ＜0.05).Conclusions The results suggested that rs501120 was tightly associated with CHD in people younger than 60 years or had diabetes.

The aim of the present study was to evaluate the effect of storage conditions,pretreatment,temperature,time and excystation solutions on in vitro excystation of Cryptosporidium oocyst.Cryptosporidium andersoni oocyst was used as a model and the results showed that 0.5% sodium hypochlorite could enhance the excystation rates.But there was no significant difference compared with oocysts untreated by sodium hypochlorite(P＞0.05).0.75% synthetic sodium taurocholate and 1% bile solution could urge the excystation of oocysts,which were significantly different compared with the excystation rate of oocysts in 0.25% trypsin solution or in PBS(P<0.05).The excystation rates of oocysts in acidic water (pH =3) were similar with the rates in PBS (pH =7.2) but significantly different from the rates in alkaline water (pH =9) (P<0.01).Additionally,the excystation rate of oocysts in water of 24℃ was significantly lower than in water of 37℃(P<0.01),and the excystation rate of oocysts raised gradually at 37℃ with the passage of time.It's concluded that temperature,acidity and excystation solution were vital factors for the in vitro excystation of Cryptosporidium oocyst.A higher excystation rate could be observed when oocysts were pretreated with 0.5% sodium hypochlorite and treated with 0.75% synthetic sodium taurocholate at 37℃ for 3 hours.

To understand the Escherichia coli (E .coli) O157∶ H7 isolated from cow in Zhengzhou ,Henan Province ,a total of 146 samples of cow fecal and milk were collected in the different farms ,and E .coli O157∶ H7 was detected with mul-tiplex polymerase chain reaction (PCR) in our laboratory .Then the biochemical characteristics ,growth dynamic ,the biofilm formation ,and the toxin genes of the E .coli O157∶ H7 isolates were analyzed .The results showed that 2 strains of E .coli O157∶H7 were found ,with the detection rate of 1 .4% ,and the isolates were named as L1 and L2 in current study ,respec-tively .The E .coli O157∶H7 clinical isolates had the same biochemical characteristics with that of the typical E .coli .The L1 and L2 isolates presented similar growth curve ,which entered into the log phase earlier than that of the standard strain .L1 strain formed thick ,confluent ,complete biofilm after 48 hours post-inoculation ,and the biofilm of L2 strain was formed com-pletely in 36 hours .The two E .coli O157∶ H7 isolates were positive with eaeA and hlyA genes ,and the L1 strain also carried the Stx2 virulence gene .Our results reinforce the epidemiological data of E .coli O157∶H7 ,and underscore the need for more effective surveillance of animal-derived E .coli O157∶H7 isolates in Zhengzhou City ,China .

The relationship between hyperhomocysteinemia and coronary artery disease (CAD) was investigated and the influence of environmental factors (Folate, VitB12) and genetic factors ［N5,N10-methylenetetrahydrofolate reductase gene (MTHFR) or MTHFR gene mutation］ on plasma homocysteine (Hcy) levels and the risk of CAD observed. Fifty-one CAD patients and 30 CAD-free subjects were recruited in the study. The polymorphisms of MTHFR gene were analyzed by PCR-RFLP and plasma total Hcy levels were measured by high performance liquid chromatography with fluorescence detection. Plasma folate and vitamin B12 concentrations were measured by an automated chemiluminescence method. It was found that mean total plasma Hcy concentrations were significantly higher in CAD patients than in CAD-free subjects (P<0.01). The differences were also apparent among the three genotypes of MTHFR gene in CAD group (P<0.05). There was no significant difference in the genotype distributions and allele frequencies between the two groups. A strong inverse correlation was found between folate or vitamin B12 and plasma Hcy levels according to MTHFR genotype (P<0.01). It was concluded that hyperhomocysteinemia is a new independent risk factor for CAD. However, MTHFR gene mutation alone does not relate significantly to the morbidity of CAD since hyperhomocysteinemia and its influence on the risk of CAD are decided by both environmental and genetic factors. Supplementary treatment with vitamins B can effectively lower the plasma levels of Hcy, thus maybe reduceing the risk of CAD.

The relationship between hyperhomocysteinemia and coronary artery disease (CAD) was investigated and the influence of environmental factors (Folate, VitB12) and genetic factors ［N5,N10-methylenetetrahydrofolate reductase gene (MTHFR) or MTHFR gene mutation］ on plasma homocysteine (Hcy) levels and the risk of CAD observed. Fifty-one CAD patients and 30 CAD-free subjects were recruited in the study. The polymorphisms of MTHFR gene were analyzed by PCR-RFLP and plasma total Hcy levels were measured by high performance liquid chromatography with fluorescence detection. Plasma folate and vitamin B12 concentrations were measured by an automated chemiluminescence method. It was found that mean total plasma Hcy concentrations were significantly higher in CAD patients than in CAD-free subjects (P<0.01). The differences were also apparent among the three genotypes of MTHFR gene in CAD group (P<0.05). There was no significant difference in the genotype distributions and allele frequencies between the two groups. A strong inverse correlation was found between folate or vitamin B12 and plasma Hcy levels according to MTHFR genotype (P<0.01). It was concluded that hyperhomocysteinemia is a new independent risk factor for CAD. However, MTHFR gene mutation alone does not relate significantly to the morbidity of CAD since hyperhomocysteinemia and its influence on the risk of CAD are decided by both environmental and genetic factors. Supplementary treatment with vitamins B can effectively lower the plasma levels of Hcy, thus maybe reduceing the risk of CAD.

Associations between “lipid-related” candidate genes,blood lipid concentrations and coronary artery disease (CHD) risk are not clear.We aimed to investigate the effect of three newly identified lipids loci from genome-wide association studies on CHD and blood lipid levels in Chinese Han population.The genotypes of SNPs at three newly identified lipid loci and blood lipids concentrations were examined in 1360 CHD patients and 1360 age- and sex-frequency matched controls from an unrelated Chinese Han population.Allele T of rs16996148 occurred less frequently in CHD patients with the odds ratio (OR) being 0.64 (95％ CI 0.50 to 0.81),after adjusting for conventional risk factors and was associated with a 33％ decreased CHD risk (P＜0.01) comparing with the major allele G.Individuals with GT genotype had the lowest CHD risk.No associations were found between the polymorphisms of other two loci with CHD risk and all three SNPs had no effect on lipid profile in this population.SNP rs16996148 on chromosome 19p13 is significantly associated with lower risk for CHD in Chinese Han population.However,it remains unresolved why these lipid-related loci had significantly less effects than the correspondingly expected effects on blood lipids levels in this population.

The association between atrial natriuretic peptide (ANP) polymorphism and coronary heart disease (CHD) was studied in Chinese population. The genotypes of ANP T2238C and ANP C-664G were detected by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) methods in 158 consecutive CHD patients and 165 controls. It was found that the distribution of A2A2 genotype in CHD group was significantly higher than that in control group (P＜0.05). Stepwise Logistic regression analysis revealed that male, smoking, history of hypertension,history of diabetes, family history of hypertension, high level of serum cholesterol, and ANP T2238C polymorphism were the possible risk factors in patients with CHD (P＜0.05). However, there was no significant difference between the patients with CHD and the control group in the distribution of ANP C-664G polymorphism (P＞0.05). The results suggest that A2A2 T2238C genotype could be one of the risk factors for CHD (P＜0.05, OR: 1.80, 95% CI:1.03-3.15).