Characterization and polymorphic analysis of 4.5 kb genomic full-length HLA-C in the Chinese Han population

This study used long-range polymerase chain reaction to sequence 4.5 or 4.3 kb of genomic DNA covering human leukocyte antigen C (HLA-C) and its flanks in 45 Chinese Han subjects to better characterize variation in the gene in a single population. Sequences of 35 HLA-C alleles were obtained from the population, including major alleles of 13 lineages of HLA-C. Four novel alleles, C*03:04:01:02, C*04:01:01:03, C*08:22, and C*17:01:01:02, were identified, and complete full-length sequences of 18 HLA-C alleles were obtained for the first time. All sequences herein reported also represent extensions through the promoter region and the 3'-untranslated region. Fourteen 5'-nucleotide sequences and 14 3'-nucleotide sequences were detected outside the coding region. In total, 316 single-nucleotide polymorphisms unequally distributed in HLA-C subregions were observed. In addition to exons 2 and 3, nucleotide variability was found to be particularly high in exon 5, which encodes the transmembrane region. The differentiation of the C*07 and C*17 lineages in this region accounts for the high variability. The congruence of phylogeny across most regions of the gene suggests that gene conversion or recombination has not markedly influenced divergence between lineages in the evolution of HLA-C.

Loss of type III transforming growth factor-beta receptor expression is due to methylation silencing of the transcription factor GATA3 in renal cell carcinoma

Loss of transforming growth factor-beta receptor III (TbetaRIII) correlates with loss of transforming growth factor-beta (TGF-beta) responsiveness and suggests a role for dysregulated TGF-beta signaling in clear cell renal cell carcinoma (ccRCC) progression and metastasis. Here we identify that for all stages of ccRCC TbetaRIII expression is downregulated in patient-matched tissue samples and cell lines. We find that this loss of expression is not due to methylation of the gene and we define GATA3 as the first transcriptional factor to positively regulate TbetaRIII expression in human cells. We localize GATA3's binding to a 10-bp region of the TbetaRIII proximal promoter. We demonstrate that GATA3 mRNA is downregulated in all stages, of ccRCC, mechanistically show that GATA3 is methylated in ccRCC patient tumor tissues as well as cell lines, and that inhibiting GATA3 expression in normal renal epithelial cells downregulates TbetaRIII mRNA and protein expression. These data support a sequential model whereby loss of GATA3 expression through epigenetic silencing decreases TbetaRIII expression during ccRCC progression.

High-resolution melting analysis for the rapid detection of an intronic single nucleotide polymorphism in SLC22A12 in male patients with primary gout in China

OBJECTIVES

The human urate transporter 1 (URAT1, encoded by SLC22A12) was recently identified as the major absorptive urate transporter protein in the kidney responsible for regulating blood urate levels. The present study was designed to investigate the rs893006 polymorphism (GG, GT, and TT) in SLC22A12 in a total of 292 Chinese male subjects. Differences of clinical characteristics among the genotype groups were analysed.

METHODS

A total of 124 consecutive patients with diagnosis of primary gout and 168 healthy male volunteers were enrolled in this study. Demographic and clinical data were obtained from the patients and controls. DNA was purified from peripheral blood and the rs893006 polymorphism was determined with sequencing analysis. In addition, DNA samples were detected by high-resolution melting (HRM) analysis. Melting curves were analysed as fluorescence difference plots. The shift and curve shapes of melting profiles were used to distinguish the different genotypes.

RESULTS

GG, GT, and TT genotypes were unambiguously distinguished with HRM technology. Genotyping based on HRM analysis was fully concordant with the sequencing. Serum uric acid levels in the TT genotype subjects were significantly lower than those in the GG and GT genotypes. However, no differences among the groups were found in body mass index (BMI), blood pressure, creatinine, total cholesterol, and triglycerides. The TT genotype was observed more frequently among the low uric acid group than the high uric acid group.

CONCLUSIONS

HRM analysis is a simple, rapid and accurate one-tube assay for genotyping the SLCSSA12 gene. The rs893006 polymorphism in SLC22CA12 was confirmed to be a genetic risk for hyperuricaemia among the Chinese male population.

Expression of recombinant rat Neurotrophin-3 in Chinese hamster ovary cells

The CHO cell line stably producing recombinant rat NT-3 was established. The insertion of rNT-3 cDNA into transferred cell gonome was analyzed with Southern blot. The expressed protein was identified by Dot ELISA (enzyme-linked immunosorbent assay) and Western blot. Western blot showed a clear specific band of about 14 ku for NT-3. The mean level of rNT-3 in four NT-3cDNA/CHO cell lines was about 2 100 ng/10(6) cells/48 h determined by EIA. The conditioned-medium (CM) of NT-3cDNA/CHO cells could promote the fiber outgrowth of the dissociated dorsal root ganglion of 8-day-old chick embryos, which shows a dose-response relationship. A half-maximal concentration of the biological activity (EC50) of the recombinant protein was approximately 16.7 ng/mL. The MoAb 3W3 of NT-3 could neutralize the biological activity of the rNT-3.

No association found between the promoter variants of TNF-alpha and diabetic retinopathy in Chinese patients with type 2 diabetes

PURPOSE

Necrosis tumor factor (TNF) is known to be associated with diabetic retinopathy (DR). The objective of this study was to examine the genetic variations of TNF-alpha and assess their possible relationship to DR in type 2 diabetic patients in the Chinese population.

MATERIALS AND METHODS

We conducted a case-control association study between the promoter variants of TNF-alpha and diabetic retinopathy in Chinese patients with type 2 diabetes. We selected three variants in the promoter region of TNF-alpha, namely rs1800629, rs1041981, and rs2857713.

RESULTS

No individual SNP nor any haplotype was found to be associated with DR in our study.

CONCLUSION

This is the first study to report TNF-alpha polymorphisms in patients with DR in the Chinese population. The results suggest that the variants among the promoter of TNF-alpha are unlikely to play a major role in the susceptibility to DR in Chinese patients with type 2 diabetes.

2-Dimensional MEMS dielectrophoresis device for osteoblast cell stimulation

A fixed microelectrode device for cell stimulation has been designed and fabricated using micro-electro-mechanical systems (MEMS) technology. Dielectrophoretic forces obtained from non-uniform electric fields were used for manipulating and positioning osteoblasts. The experiments show that the osteoblasts experience positive dielectrophoresis (p-DEP) when suspended in iso-osmotic culture medium and exposed to AC fields at 5 MHz frequency. Negative dielectrophoresis (n-DEP) is obtained at 0.1 MHz. The viability of osteoblasts under dielectrophoresis has been investigated. The viability values for cells exposed to DEP are nearly three times higher than the control values, indicating that dielectrophoresis may have an anabolic effect on osteoblasts.

Characterization of HLA-B*5516, -B*1313, -B*9512, and -DRB1*1457 alleles identified in a southwest Chinese population

The human leukocyte antigen (HLA)-B*5516 allele differs from the B*5502 by a single 97 T --> C substitution (His to Tyr at position 33) in exon 2. The B*1313 allele results from 419 T --> A and 420 A --> C substitutions, encoding a Leu to Tyr substitution at 140 in exon 2 of the B*1301 allele. The B*9512 allele differs from B*1502 by a single 360 G --> C substitution (Gln to His at 120) in exon 3. The DRB1*1457 allele appears to be a hybrid molecule generated by recombination between the DRB1*13 and DRB1*14 alleles. The serological equivalents of these new alleles are HLA-B22, -B13, -B15, and DR13, respectively. Family studies detected two rare haplotypes: A*11, B*9512, DRB1*14 and A*24, B*52, Cw*07, DRB1*1457, DRB3*020201, DQB1*050301. The gene frequencies of these alleles in the Chinese population are less than 0.0001.

Development and psychometric tests of the Chinese-version Low Vision Quality of Life Questionnaire

BACKGROUND/AIMS

To develop and assess the psychometric validity of a Chinese language Vision Health related quality-of-life (VRQoL) measurement instrument for the Chinese visually impaired.

METHODS

The Low Vision Quality of Life Questionnaire (LVQOL) was translated and adapted into the Chinese-version Low Vision Quality of Life Questionnaire (CLVQOL). The CLVQOL was completed by 100 randomly selected people with low vision (primary group) and 100 people with normal vision (control group). Ninety-four participants from the primary group completed the CLVQOL a second time 2 weeks later (test-retest group). The internal consistency reliability, test-retest reliability, item-internal consistency, item-discrimination validity, construct validity and discriminatory power of the CLVQOL were calculated.

RESULTS

The review committee agreed that the CLVQOL replicated the meaning of the LVQOL and was sensitive to cultural differences. The Cronbach's alpha coefficient and the split-half coefficient for the four scales and total CLVQOL scales were 0.75-0.97. The test-retest reliability as estimated by the intraclass correlations coefficient was 0.69-0.95. Item-internal consistency was > 0.4 and item-discrimination validity was generally < 0.40. The Varimax rotation factor analysis of the CLVQOL identified four principal factors. the quality-of-life rating of four subscales and the total score of the CLVQOL of the primary group were lower than those of the Control group, both in hospital-based subjects and community-based subjects.

CONCLUSION

The CLVQOL Chinese is a culturally specific vision-related quality-of-life measure instrument. It satisfies conventional psychometric criteria, discriminates visually healthy populations from low vision patients and may be valuable in screening the local community as well as for use in clinical practice or research.

Epidemiology survey of rhegmatogenous retinal detachment in Beixinjing District, Shanghai, China

PURPOSE

To investigate the recent incidence and related risk factors of rhegmatogenous retinal detachment (RRD) in Chinese people.

METHODS

This study was an incidence survey based on data for 108,132 persons in Beixinjing District, Shanghai, China. Patients with RRD were inpatients, outpatients, and patients from the local health network. Patients with RRD were compared with control subjects who were matched by sex, age, and block of residence. Previous population data were used to estimate the whole and specific incidence of RRD. Some factors relevant to the incidence of RRD were found by comparing the patients with RRD with the control subjects.

RESULTS

Between January 1996 and December 1999, 61 cases of RRD occurred. The annual incidence of RRD was 11.3 cases per 100,000 population in 1996, 14.1 cases per 100,000 population in 1997, 14.1 cases per 100,000 population in 1998, and 17.9 cases per 100,000 population in 1999. The average annual incidence was 14.4 cases per 100,000 population (95% confidence interval, 10.0-18.6). There were 29 males and 32 females with RRD. The incidence of RRD among persons older than 40 years was high, especially among those between 40 and 59 years of age. The proportion of individuals with high myopia (more than -6 diopters) was significantly higher in the patient group than in the control group (P < 0.001).

CONCLUSION

The annual incidence of RRD among a local Chinese population increased over 4 years. This disease is strongly associated with high myopia and age.

Dual inhibition of sister chromatid separation at metaphase

Separation of sister chromatids in anaphase is mediated by separase, an endopeptidase that cleaves the chromosomal cohesin SCC1. Separase is inhibited by securin, which is degraded at the metaphase-anaphase transition. Using Xenopus egg extracts, we demonstrate that high CDC2 activity inhibits anaphase but not securin degradation. We show that separase is kept inactive under these conditions by a mechanism independent of binding to securin. Mutation of a single phosphorylation site on separase relieves the inhibition and rescues chromatid separation in extracts with high CDC2 activity. Using quantitative mass spectrometry, we show that, in intact cells, there is complete phosphorylation of this site in metaphase and significant dephosphorylation in anaphase. We propose that separase activation at the metaphase-anaphase transition requires the removal of both securin and an inhibitory phosphate.

[Applications of sol-gel method in preparation of biomaterials]

In recent years, there has been a great development in the applications of sol-gel method in preparation of biomaterials. In this article, the sol-gel process and its use in preparation of biomaterials are reviewed, and the authors also introduce their studies to be done. Finally, the future development trend are forecasted.

[Preparation and analysis of pure type II collagen from porcine articular cartilage]

This investigation was aimed at the preparation of pure type II collagen from porcine articular cartilage and the feasible method for producing type II collagen in bulk. After dispersal of the porcine articular cartilage, the proteoglycans were extracted by guanidinium hydrochloride and dissolved by pepsin in acid solvent. The contaminants including denatured and degraded protein and other collagen was removed via the repeated procedure of purification. For obtaining the purer type II collagen, the chromatography with sepharose H. P. Column was also used. The purity of the sample was compared with the type II collagen produced by Sigma Company. Both type II collagens were characterized by SDS-PAGE electrophoresis, amino acid analysis and maximal violet chromatography, and all of the results accorded with the standard photograph in the references. The purity of the sample was higher than that of the product of Sigma Company. This prepared collagen of type II is a product of high purity. The raw materials are the common porcine articular cartilage, which is rich in resource and low in cost. Therefore, it is suitable to produce type II collagen in batches.

Determination of scopolamine, atropine and anisodamine in Flos daturae by capillary electrophoresis

A capillary electrophoresis method was developed for the separation and determination of tropane alkaloids in Flos daturae plants. Separation was performed on a fused silica capillary(42.1 cm x 50 microm i.d.) at an applied voltage of 20 kV. Scopolamine, atropine and anisodamine were well separated in the buffer of 50 mmol/L phosphate buffer (pH 5.0) containing 20% (v/v) tetrahydrofuran (THF). Beer's law was obeyed in the range of concentration of 2.4-21.8 microg/mL for scopolamine, 4.0-36.0 microg/mL for atropine and 2.6-23.7 microg/mL for anisodamine, respectively, and the correlation coefficients were over 0.999 (n = 6). The developed method was applied for the analysis of herb samples.

Analysis of terpene compounds in Cimicifuga foetida L. by reversed-phase high-performance liquid chromatography with evaporative light scattering detection

An RP-HPLC method with evaporative light scattering detection (ELSD) was developed for the analysis of terpene compounds in traditional Chinese medicine. Actein, 27-deoxyactein and cimicifugoside in a typical Chinese medicine of Cimicifuga foetida L. were quantitatively analyzed. Comparing ELSD with UV detection under the same eluent conditions, the former showed better sensitivity and a more stable baseline. The ELSD responses versus sample size of three terpenes and those in double logarithmic were investigated. The good calibration curves in double logarithmic coordinator for actein, 27-deoxyactein and cimicifugoside were obtained. Three solutions for the extraction of the terpene compounds were also compared, the results indicated that methanol-water (80:20) is the best among them. The method was applied to quantify actein, 27-deoxyactein and cimicifugoside in Cimicifuga foetida L. from Hunan, China. It was shown that ELSD is an effective detection method for the analysis of the non-volatile terpenes in traditional Chinese medicine.