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The article discusses the study which aims to explore the cloning and expression of bovine adiponectin gene in Pichia pastoris amplified by real time polymerase chain reaction (RT-PCR).

To further study the unsteady characteristics of cavitation flow, a new mathematical cavitation model based on Rayleigh-Plesset equation was given out. Both steady and unsteady cavitation flow generated from hemispherical cylinder were simulated numerically by using the new model in 2D axial symmetrical coordinates. The successful application and validation of the new model show that the condensation occurs when the bubble expands and evaporation happens when the bubble collapses. It can be seen from the analysis of the experiments and the numerical simulations that, according to the cavitation number, the cavitation flow is divided into three types, i. e. supercavitation flow, secondary cavitation flow and weak cavitation flow. Due to the unsteadiness, each type of cavitation flow corresponds to different model coefficients. The new cavitation model can successfully capture the unsteady details of the cavitation flow, and it is helpful to further study the mechanism of cavitation. [ABSTRACT FROM AUTHOR]

Objective: To investigate the prenatal diagnosis of a case of SEA-HPFH deletion combined with beta-thalassemia in a Chinese family., Methods: Gap-PCR and RDB methods were applied to test the genotype for the family., Results: Mother showed a SEA-HPFH thalasemia trait phenotype, while her genotype was heterozygote for SEA-HPFH deletion; father showed a beta-thalassemia trait phenotype, while his genotype was heterozygote for IVS-II-654 mutation; the genotype of fetus was normal in these tests., Conclusion: Regular thalassemia genes and deletion beta-thalassemia genes can be used in prenatal diagnosis of the case at risk for compound heterozygotes of SEA-HPFH deletion and beta-thalassemia.

Objective: To investigate the hematologic characteristics and gene diagnosis of patients with Thailand deleted α-thalassemia 1, so as to provide the information for clinical genetic counseling., Methods: The clinical data of 32 patients with Thailand delated α-thalassemia 1 were analyzed retrospectively; the hematologic characteristics and gene diagnosis of Thailand deleted type were investigated by using routine hematologic examination, genetic detection of common thalassemia and Thailand deleted α-thalassemia 1., Results: Among 32 cases, the Thailand deleted α-thalassemia 1 heterozygote was found in 29 cases, the Thailand deleted α-thalassemia 1 and α(3.7) gene deletion double heterozygote were found in 1 case, the Thailand deleted α-thalassemia 1 with β-thalassemia (1 case with codons 41-42 mutation heterozygous, 1 case with CD17 mutation heterozygous) was found in 2 cases by detection. The MCV and MCH levels were decreased in all cases of Thailand deleted thalassemia 1, there were significant differences in RBC, MCV, MCH (P<0.05) between normal control and Thailand deletion α-thalassemia 1 group; there were also significant differences in MCHC (P<0.05) between Southeast asia thalassemia and Thailand deleted α-thalassemia 1 group., Conclusion: There are no significant differences in hematological parameters except MCHC between Southeast asia thalassemia and Thailand deleted α-thalassemia 1 group. moreover the Thailand deleted α-thalassemia 1 in a certain proportion exists in area with high incidence of thalassemia, therefor the clinicians should pay more attention to the screen and diagnosis of Thailand delated α-thalassemia and can exactly diagnose the Thailand delected α-thalassemia 1 on the basis of comprehensive analysis of conventional and Thailand delected α-thalassemia 1 detection results, clinical presentation, hematologic parameters and ultrasonic examination, so as to avoid the birth of child with severe and intermidiate type α-thalassemia caused by Thailand deleted α-thalassemia 1.

Objective: To investigate the gene prevalence and spectrum of alpha- and beta-thalassemia in Fujian province., Methods: A total of 11 234 of neonatal cord blood samples were collected for a prevalence study of alpha- and beta-thalassemia. All subjects included in this study were registered in 9 cities of Fujian province. A complete blood count and high performance liquid chromatography (HPLC) were performed in all samples, with microcytosis (MCV≤ 79 f1 and MCH≤ 27 pg) or HPLC positive cases further studied by DNA analysis. alpha- and beta-thalassemia were determined by using gap-PCR and reverse dot blot (RDB) assays. Unknown positive samples were analyzed directly with DNA sequencing., Results: Of all 11 234 cord blood samples, 356 were identified as from alpha-thalassemia gene carriers, 7 deletion genotypes were identified including 236 (--SEA/ α α) cases, 67 (α 3.7/ α α) cases, 24 (alpha 4.2/alpha alpha) cases, 3 (alpha 3.7/ SEA) cases, 1 (alpha 4.2/ SEA) cases, 1 (alpha 3.7/ alpha 3.7) cases, 1 (alpha 3.7/ alpha 4.2) cases; 3 non-deletion genotypes were detected, including 7 (alpha alpha QS/ alpha alpha) cases, 3 (α α CS/α α) cases, 2 (α α WS/ α α) cases, the most common mutation was SEA/α α, which accounted for 66.29%, 148 individuals were found to have beta-hemoglobin gene mutations. 12 different mutations were identified, namely 65 IVS-2 654 (C>T) cases, 40 CD41-42(-TCTT, 12 CD17(A>T) cases, 10 -28(A>G) cases,7 CD27-28(+C) cases, 5 start codon ATG>AGG cases, 2 CD26(G>A) cases, 1 CD71-72(+A) cases, 1 IVS-1-1(G>T) cases, 1 CD43(G>T) cases, 2 -29(A>G) cases, 2 Codon 36 (-C) cases, the most common mutation was IVS-2 654(C>T) and CD41-42(-TCTT), which accounted for 70.95%. A novel beta-globin gene mutation CD36 (-C) allele was also detected. The carrier rate of thalassemia in Fujian population is 4.41%. In addition, 9 beta-thalassemia carriers were found with alpha-thalassemia mutation., Conclusion: The research has revealed the type of gene mutations in alpha- and beta-talassemia in Fujian province. The beta-thalassemia mutations in Fujian province are complex, which were also obviously heterogeneous. This will significant value for screening the incidence, provide the valuable information for genetic counseling and prenatal diagnosis.

Objective: To explore the relationship between gene polymorphism of GABAA receptors and childhood autism by detecting rs140682, rs2081648 and rs140679 site of single nucleotide polymorphism (SNP) in GABAA receptors gene., Methods: A total of 94 children with autism and 124 normal children were enrolled in a hospital from November 2010 to May 2011. Childhood autism rating scale (CARS) and autism behavior checklist (ABC) were used to evaluate or investigate the case group. After collecting venous blood and extracting the genome DNA, the allele and genotype of SNP rs140682, rs2081648 and rs140679 site in GABAA receptors gene were detected by PCR-RFLP. The allele and genotype of case group and control group were analyzed by χ(2) test, while the score of scales was analyzed by Spearman rank correlation analysis., Results: The age of the case group was 5.12 ± 0.32, and it was 5.25 ± 0.27 in the control group (P < 0.05). In case group, the frequency of genotype CC, CT and TT of rs140682 site was 44, 41 and 9, while it was 48, 65, and 11 in control group (P > 0.05), respectively. The frequency of genotype AA, AG and GG of rs2081648 site was 8, 58 and 28 in case group, while it was 12, 49 and 63 in control group (P < 0.05), respectively. In case group, the frequency of genotype CC, CT and TT of rs140679 site was 15, 36 and 43, while it was 18, 59 and 47 in control group (P > 0.05), respectively. It was revealed by Spearman rank correlation analysis that of rs2081648 site, there was a positive correlation between genotype AG and sensation factor (S), social intercourse factor (R), and language factor (L) of autism behavior checklist (ABC) (r values were 0.149, 0.165 and 0.155, all P values < 0.05). A negative correlation between genotype GG and S, R, L and self-help factor (V) was proved (r values were -0.140, -0.173, -0.158 and -0.135, all P values < 0.05). There was a positive correlation between allele A and R and L factors (r values were 0.153 and 0.137, all P values < 0.05), while a negative correlation between allele G and R and L factors (r values were -0.153 and -0.137, all P values < 0.05). In case group, 42 children were diagnosed with mild-to-moderate autism, while 52 children were severe autism. There was no statistically significant correlation between allele or genotype of SNP rs140682 and rs140679 site and the degree of autism (P > 0.05). There was a positive correlation between allele A and genotype AG and the degree of autism (r values were 0.147 and 0.616, all P values < 0.05), while a negative correlation between allele G and genotype GG and the degree of autism (r values were -0.159 and -0.616, all P values < 0.05)., Conclusion: The SNP rs2081648 site which located in GABAA receptors gene may be related to autism. No evidence for significant association between rs140682 and rs140679 site and autism was found.

Objective: To characterize full length glycoprotein 120 gene variations of 21 HIV-1 CRF01&#95;AE isolated in Fujian, China, so as to help in the immunogenic research and vaccine design., Methods: Twenty-one peripheral blood samples were randomly collected form 100 HIV-1CRF01&#95;AE infected persons in Fujian 2004 approximately 2005. DNA was extracted, Nested-PCR was used to amplify the envelop protein full length gp120 gene. The PVR products underwent Sepharose electrophoresis. Genotype identification was done by BLAST program. Sequence analysis was conducted with Megalign and CLUSTAL1.83. Phylogenetic tree and genetic distance were analyzed by Neighbor-joining method and Distance program of MEGA software. The amino acid similarity analysis was done with DNASIS, and N-glycosylation site analysis was done with N-GLYCOSIDE program., Results: Phylogenetic tree analysis showed that these 21 HIV-1 subtype CRF01&#95;AE strains clustered with the AE reference strain, with an overall genetic distance of 9.5% +/- 2.5%. There were four types of V3 loop central motif: GPGQ (71.43%), GPGR (19.05%), GPGH (4.76%), and GQGQ (4.76%). Prediction of the potential use of co-receptors on the basis of the critical amino acids within V3 loop disclosed potential use of CCR4/CCR5 in 16 of the 21 sequences (76.19%), potential use of CCR4/CCR5 in 1 sequence (4.76%), and 4 samples (19.05%) failed to be predicted. Amino acid sequence analysis showed that V3 region was relatively conservative, whereas V1, V2, V4, and V5 wee more variable. N-linked glycosylation site analysis showed that most of the 21 sequences were relatively conservative., Conclusion: Sequences analysis show Most of the CRF01&#95;AE virus strains in Fujian have a complicated source, and most of them are closely related to those of Southeast Asia and belong to the non-syncytium inducing (NSI) type.

Objective: To collect background information on drug-resistant HIV-1 strains in various regions before the start of nation-wide antiretroviral therapy in China., Methods: Twenty percent of the 2,000 blood samples from antiretroviral therapy naive patients collected for the 2nd national HIV molecular epidemiology survey (NHMES) in 2002 were randomly sampled for this study. The entire protease gene and 20-230 amino acids of the reverse transcriptase gene were amplified by PCR from provirus DNA and sequenced. The results were analyzed with HIV db-Drug Resistance Algorithm and genotypic resistance mutations were determined to particular anti-HIV drugs., Results: Totally 164 protease gene sequences and 138 reverse transcriptase gene sequences were obtained from patients; 0.61% of 164 sequences displayed primary resistance mutations in the protease gene, whereas 99.39% carried 1 or more secondary mutations. Genotypic resistance to at least one nucleoside reverse transcriptase inhibitors (NRTI) was present in 5.80%,and resistance to at least one non-nucleo side reverse transcriptase inhibitors (NNRTI) was present in 1.45% of samples., Conclusion: The prevalence of genotypic drug resistance is very low in drug-naive HIV infected patients from 21 provinces of China tested in this study. Laboratories participated in the NHMES have organized a network to provide drug resistance monitoring service in the current nation-wide antiviral treatment program in China.

Objective: To characterize full length gag gene and partial pol gene of Chinese prevalent HIV-1 B/C recombinant strains, to explore the genetic difference between parent strains and B/C recombinant strains, and to investigate the mechanism of different biologic phenotype among them., Methods: The peripheral blood samples were collected from 138 HIV-positive persons from 12 regions of China respectively. Samples of total DNA were extracted from the peripheral blood mononuclear cells to undergo nested PCR and sequencing. The 117 HIV-1 CRF07-BC strains and 21 HIV-1 CRF08-BC strains were screened with the resulted that 5 CRF07-BC samples from Xinjiang and 1 CRF08-BC sample from Chongqing were regarded as the most potential new type recombinant viruses. The sequences thus obtained underwent phylogenetic tree analysis and amino acid variation analysis. Simplot software was used to analyze the sequence recombination and identify the breakpoints of B/C recombinant strains. To confirm the breakpoints, separate phylogenetic analysis according to the breakpoints was performed with MEGA software. The genetic distances of different gene fragments were calculated by DISTANCE program in GCG software package. The gene dispersion in the gene fragment of a length of 2550 bp of the recombinant HIV-1-B/C and the potential influence of gene recombination on its function were further analyzed., Results: No change of breakpoint was found in the 5 samples from Xinjiang. But a breakpoint shift of 160 nucleotides occurred in RT region of a sample from Congqing city., Conclusion: CRF07-BC and CRF08-BC remain the main prevalent HIV-1 B/C recombinant strains in China. No epidemic of new mosaic recombinant strain is found. The variation of amino acids at the sites 286 and 799 may be the reasons of the transmission dominance of the B/C recombinant strain.

Objective: To identify variations in the env gene of human immunodeficiency virus type 1 (HIV-1) subtype CRF01-AE strains circulating in China and to elucidate the potential relationship between genetic variation and evolutionary pressure., Methods: Fragments of the HIV-1 env gene were amplified by nested-polymerase chain reaction (n-PCR) from the whole blood of HIV-1 infected individuals from four provinces in Southeast China (Guangdong, Hunan, Jiangsu and Jiangxi). The PCR products were then directly sequenced by ABI 377 DNA sequencers. The sequences covering the env V3-V4 region of 34 HIV-1 subtype CRF01-AE strains were selected to analyse phylogenetic trees and amino acid mutations. The accumulation of synonymous (Ks) and antonymous (Ka) substitutions as well as Ks/Ka ratios were calculated using DIVERGE., Results: Phylogenetic trees showed that the 34 HIV-1 subtype CRF01-AE strains from China clustered with the Chinese AE reference strain (AE.97CNGX2F), as well as with the reference strains from Thailand (AE.CM240 and AE.93TH253). The amino acid sequences of the env V4 and C3 regions in the samples were highly variable, compared with those of V3 and V3-downstream regions. The V3 loop central motif in the majority (87.5%) of the strains was GPGQ. The majority of strains did not contain positively charged amino acids at positions 306 and 320 in V3 loop. The N-linked glycosylation sites in the V3-V4 region and flanking regions in these strains were relatively conserved. Analysis of the entire region showed that the mean Ks values were significantly higher than that of the Ka values (P < 0.001), with the Ks/Ka significantly higher than 1.0 (P < 0.001). In contrast, the Ks/Ka ratio in the V4 region was significantly lower than 1.0 (P < 0.01)., Conclusions: Our study indicated that the majority of HIV-1 subtype CRF01-AE strains circulating in China were highly homogeneous. The amino acid sequences of the V4 and C3 regions were significantly more variable than those of the V3 loop. Our analysis also suggested that the phenotype of nearly all strains was likely to be non-syncytium inducing (NSI). Finally, the variation found in the V3-V4 sequence was significantly influenced by functional constraints as opposed to positive selective pressure, while the variability of the lone V4 region was strongly related to positive selective pressure.