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D Yang

Publications and source records attributed to D Yang.

At least 19 recordsLinked to original sources
PubMed2006

Enhanced electroweak penguin amplitude in B-->VV decays.

We discuss a novel electromagnetic penguin contribution to the transverse helicity amplitudes in B decays to two vector mesons, which is enhanced by two powers of mB/Lambda relative to the standard penguin amplitudes. This leads to unique polarization signatures in penguin-dominated decay modes such as B-->rhoK* similar to polarization effects in the radiative decay B-->K*gamma and offers new opportunities to probe the magnitude and chirality of flavor-changing neutral current couplings to photons.

Journal Article↗
PubMed2006

Characterization and expression of a cDNA encoding a tubuliform silk protein of the golden web spider Nephila antipodiana.

Spider silks are renowned for their excellent mechanical properties. Although several spider fibroin genes, mainly from dragline and capture silks, have been identified, there are still many members in the spider fibroin gene family remain uncharacterized. In this study, a novel silk cDNA clone from the golden web spider Nephila antipodiana was isolated. It is serine rich and contains two almost identical fragments with one varied gap region and one conserved spider fibroin-like C-terminal domain. Both in situ hybridization and immunoblot analyses have shown that it is specifically expressed in the tubuliform gland. Thus, it likely encodes the silk fibroin from the tubuliform gland, which supplies the main component of the inner egg case. Unlike other silk proteins, the protein encoded by the novel cDNA in water solution exhibits the characteristic of an alpha-helical protein, which implies the distinct property of the egg case silk, though the fiber of tubuliform silk is mainly composed of beta-sheet structure. Its sequence information facilitates elucidation of the evolutionary history of the araneoid fibroin genes.

Amino Acid Sequence↗
PubMed2006

The expression of antiapoptotic protein survivin is transcriptionally upregulated by DEC1 primarily through multiple sp1 binding sites in the proximal promoter.

Human differentially expressed in chondrocytes (DEC), mouse stimulated with retinoic acid and rat split and hairy related proteins constitute a structurally distinct class of the basic helix-loop-helix proteins. DEC1 is abundantly expressed in tumors and protects against apoptosis induced by serum starvation. In this study, we report that DEC1 antiapoptosis is achieved by inducing survivin, an antiapoptotic protein. In paired tumor-normal tissues, survivin and DEC1 exhibited a paralleled expression pattern. Tetracycline-induced expression of DEC1 in stable lines proportionally increased the expression of survivin. In reporter assays, DEC1 transactivated the survivin promoter but repressed the DEC2 promoter. In contrast to the repression, the activation was delayed and varied depending on serum concentrations and cycle blockers. Studies with reporter mutants located, in the survivin promoter, two Sp1 sites that supported DEC1 transactivation. Electrophoretic mobility shift assay and chromatin immunoprecipitation detected the presence of DEC1 in the survivin promoter. These findings establish that the survivin gene is a transcription target of DEC1, and induction of survivin is at least in part responsible for DEC1 antiapoptosis.

Adult↗
PubMed2006

Human beta-defensins.

The last decade led to the discovery and characterization of several human beta-defensins. Analysis of genomic information indicates that the number of beta-defensin-like molecules encoded by the human genome may number in the tens. Growing interest in beta-defensins steadily enhances our knowledge about various aspects of their gene location, expression patterns and the transcription factors involved in their regulation in vivo. The hallmark property of beta-defensins, their antimicrobial activity, is clearly only the tip of the iceberg in the extensive network of inter-relations within the immune system in which these peptides function. Structural studies of beta-defensins provide the molecular basis for a better understanding of their properties, functions and their potential for practical applications. In this review, we present some recent advances in the studies of human beta-defensins, with an emphasis on possible correlations between their structural and functional properties.

Amino Acid Sequence↗
PubMed2005

X-ray diffraction and Raman studies of the CuGeO3(III)-(IV) transformation under high pressures.

Both X-ray diffraction and Raman spectroscopy measurement were carried out on the same powder sample of CuGeO(3)(III) in a diamond anvil cell to high pressures at room temperature. The phase transformation of (III)-(IV) phase was observed at about 7GPa with both methods and the results were also in accord with previous powder diffraction and Raman measurements, respectively. However, the powder diffraction data were strikingly different from those reported in a recent single-crystal study on the phase (III). It is, therefore, evident that the phase transformations in CuGeO(3)(III) would be as complicated as those in CuGeO(3)(I) and that the monoclinic phase obtained from single-crystal phase (III) at approximately 7GPa is not the phase (IV) previously observed but rather a new phase (IVa) in CuGeO(3).

Minerals↗
PubMed2005

[Ischemic cardiovascular disease risks in among public servants in China].

OBJECTIVE: To examine ischemic cardiovascular disease risks (ICVD) over 10 years among china middle class (public servants) in China. METHODS: Evaluation of 10-year risks of ICVD for 2287 people with the simplified method of prediction of the cardiovascular disease risks worked out by the Collaborative Research Group of the National 10th Five Year Plan. RESULTS: (1) 98,16% of the men and 99,39% of the women have a low risk of ICVD (lower than 10%); 0,19% of the men and 0,15% of the women have a significant risk of ICVD (over 20%). (2) the average of the absolute risk of the examined subjects is higher than that of the corresponding ages of the national population. The variation is significant between men and women (p<0,001). The number of the people having an absolute risk higher than the national average increases with the age. (3) Among people with high risks (absolute risk > or =10%), the rate of SBP, FBG, TC, BMI abnormal is respectively 100%, 20,8%, 75%, 87,5%. Among the population of low risk (absolute risk<10%), those with abnormal SBP, FBG, TC, BMI are respectively 7,31%, 3,4%, 37,74%, 59,26%. The difference between the two groups is significant on all the points (p<0,001). CONCLUSION: If the average of the risks of the ICVD remains acceptable, it is nevertheless high than the national average, especially for men and older women.

Adult↗
PubMed2005

Inhibition of glycogen synthase kinase 3beta suppresses coxsackievirus-induced cytopathic effect and apoptosis via stabilization of beta-catenin.

Coxsackievirus B3 (CVB3), a common human pathogen for viral myocarditis, induces a direct cytopathic effect (CPE) and apoptosis on infected cells. To elucidate the mechanisms that contribute to these processes, we studied the role of glycogen synthase kinase 3beta (GSK3beta). GSK3beta activity was significantly increased after CVB3 infection and addition of tyrosine kinase inhibitors blocked CVB3-triggered GSK3beta activation. Inhibition of caspase activity had no inhibitory effect on CVB3-induced CPE; however, blockage of GSK3beta activation attenuated both CVB3-induced CPE and apoptosis. We further showed that CVB3 infection resulted in reduced beta-catenin protein expression, and GSK3beta inhibition led to the accumulation and nuclear translocation of beta-catenin. Finally, we found that CVB3-induced CPE and apoptosis were significantly reduced in cells stably overexpressing beta-catenin. Taken together, our results demonstrate that CVB3 infection stimulates GSK3beta activity via a tyrosine kinase-dependent mechanism, which contributes to CVB3-induced CPE and apoptosis through dysregulation of beta-catenin.

Apoptosis↗
PubMed2005

Transcriptional response signature of human lymphoid cells to staphylococcal enterotoxin B.

Two shock-inducing toxins that result in similar eventual outcome of disease were studied to determine host gene expression responses, for correlation of both similar and unique gene patterns. We initially used differential display (DD)-PCR and identified 859 cDNA fragments that were differentially expressed after 16 h of in vitro exposure of human peripheral blood mononuclear cells (PBMC) to staphylococcal enterotoxin B (SEB). Upon further examination using custom cDNA microarrays and RT-PCR analysis, we found unique set of genes to each toxin (SEB or lipopolysaccharide (LPS)), especially at early time periods. By 16 h, there was a convergence of some gene expression responses and many of those genes code for proteins such as proteinases, transcription factors, vascular tone regulators, and respiratory distress. In an attempt to replicate the findings in vivo, monkeys were challenged with SEB and the resultant gene expression responses indicated a pattern typical of SEB exposure when compared to LPS, with a similar outcome. We provide evidence that vastly diverse global gene analysis techniques used in unison can not only effectively identify pathogen-specific genomic markers and provide a solid foundation to mechanistic insights but also explain some of the toxin-related symptoms through gene functions.

Animals↗
PubMed2005

Distribution of insertion- and deletion-associated genetic polymorphisms among four Mycobacterium tuberculosis phospholipase C genes and associations with extrathoracic tuberculosis: a population-based study.

The Mycobacterium tuberculosis genome contains four phospholipase C (PLC)-encoding genes, designated plcA, plcB, plcC, and plcD, respectively. Each of the four genes contributes to the overall PLC activity of M. tuberculosis. PLC is hypothesized to contribute to M. tuberculosis virulence. Infection of M. tuberculosis strains carrying a truncated plcD gene is associated with the occurrence of extrathoracic tuberculosis. However, whether the other three plc genes are also associated with extrathoracic tuberculosis remains to be assessed. We investigated the insertion- and deletion-associated genetic diversity in all four plc genes among 682 epidemiologically and clinically well-characterized M. tuberculosis clinical isolates using PCR, DNA sequencing, and Southern hybridization. Two hundred sixty-six (39%) of the 682 isolates had an interruption in at least one of the four plc genes, most often associated with an IS6110 insertion. The plcD gene interruption was the most common: it was observed in 233 (34%) of the isolates, compared to 4.7%, 4.1%, and 5.9% for plcA, plcB, and plcC gene interruption, respectively. The association between the plc gene genotypes and disease presentation was adjusted for clustering using generalized estimating equations for both bivariate and multivariate analyses. After controlling for the genotypes of the plcABC genes and the host-related risk factors, interruption in the plcD gene remained significantly associated with extrathoracic tuberculosis (odds ratio, 3.27; 95% confidence interval, 1.32 to 8.14). The data suggest that the plcD gene might play a more important role in the pathogenesis of thoracic TB than it does in the pathogenesis of extrathoracic TB.

Bacterial Proteins↗
PubMed2005

Tissue engineering scheming by artificial intelligence.

Tissue engineers are often confused when seeking the most effective, economical and secure scheme for tissue engineering. The aim of this study is to generate tissue engineering schemes with artificial intelligence instead of human intelligence. The experimental data of tissue engineered cartilage were integrated and standardized with a centralized database, and a scheme engine was developed using artificial intelligent methods (artificial neural networks and decision trees). The scheme engine was trained with existing cases in the database, and then was used to generate tissue engineering schemes for new experimental animals. Following the schemes generated by the artificial intelligent system, we cured 18 of the 20 experimental animals. In conclusion, artificial intelligence is a powerful method for decision making in the tissue engineering realm.

Algorithms↗
PubMed2004

Inhibition of AKT survival pathway by a small molecule inhibitor in human endometrial cancer cells.

The PTEN (phosphatase and tensin homolog deleted on chromosome 10) tumour suppressor is mutated in 40-50% of human endometrial cancers. PTEN exerts its effects in part via inhibition of the antiapoptotic protein AKT. We demonstrate that two endometrial cancer cell lines that harbour PTEN mutations, Ishikawa and RL95-2, have high levels of phosphorylated AKT and high AKT kinase activity. Two additional endometrial cancer cell lines that express wild-type PTEN, Hec1A and KLE, have little phosphorylated AKT and minimal demonstrable AKT kinase activity. We tested a potential inhibitor of the AKT pathway, API-59CJ-OMe, in these four cell lines. We found that API-59CJ-OMe inhibits AKT kinase activity and induces apoptosis in the Ishikawa and RL95-2 cell lines with high AKT activity, but has little effect on Hec1A and KLE cells without AKT activity. API-59CJ-OMe may therefore have therapeutic potential for those endometrial cancers that harbour PTEN mutations and AKT activation.

Apoptosis↗
PubMed2004

A multivariate analysis of genomic polymorphisms: prediction of clinical outcome to 5-FU/oxaliplatin combination chemotherapy in refractory colorectal cancer.

In this marker evaluation study, we tested whether distinct patterns of functional genomic polymorphisms in genes involved in drug metabolic pathways and DNA repair that predict clinical outcome to 5-fluorouracil (5-FU)/oxaliplatin chemotherapy in patients with advanced colorectal cancer could be identified. Functional polymorphisms in DNA-repair genes XPD, ERCC1, XRCC1, XPA, and metabolising genes glutathione S-transferase GSTP1, GSTT1, GSTM1, and thymidylate synthase (TS) were assessed retrospectively in 106 patients with refractory stage IV disease who received 5-FU/oxaliplatin combination chemotherapy, using a polymerase chain reaction-based RFLP technique. Favourable genotypes from polymorphisms in XPD-751, ERCC1-118, GSTP1-105, and TS-3'-untranslated region (3'UTR) that are associated with overall survival were identified. After adjustment for performance status, the relative risks of dying for patients who possessed the unfavourable genotype were: 3.33 for XPD-751 (P=0.037), 3.25 for GSTP1-105 (P=0.072), 2.05 for ERCC1-118 (P=0.037), and 1.65 for TS-3'UTR (P=0.091) when compared to their respective beneficial genomic variants. Combination analysis with all four polymorphisms revealed that patients possessing > or =2 favourable genotypes survived a median of 17.4 months (95% confidence interval (CI): 9.4, 26.5) compared to 5.4 months (95% CI: 4.3, 6.0) in patients with no favourable genotype. Patients who carried one favourable genotype demonstrated intermediate survival of 10.2 months (95% CI: 6.8, 15.3; P<0.001). Polymorphisms in the TS-3'UTR and GSTP1-105 gene were also associated with time to progression. After adjustment for performance status, patients with an unfavourable TS-3'UTR genotype had a relative risk of disease progression of 1.76 (P=0.020) and those with the unfavourable GSTP1-105 genotype showed a relative risk of progression of 2.00 (P=0.018). The genomic polymorphisms XPD-751, ERCC1-118, GSTP1-105, and TS-3'UTR may be useful in predicting overall survival and time to progression of colorectal cancer in patients who receive 5-FU/oxaliplatin chemotherapy. These findings require independent prospective confirmation.

Acyltransferases↗
PubMed2004

Expression of alpha and beta parvalbumin is differentially regulated in the rat organ of corti during development.

The expression of two calcium-binding proteins of the parvalbumin (PV) family, the alpha isoform (alphaPV) and the beta isoform known as oncomodulin (OM), was investigated in the rat cochlea during postnatal development and related to cholinergic efferent innervation. Using RT-PCR analysis, we found that OM expression begins between postnatal day 2 (P2) and P4, and peaks as early as P10, while alphaPV mRNA begins expression before birth and remains highly expressed into the adult period. Both in situ hybridization and immunoreactivity confirm that OM is uniquely expressed by the outer hair cells (OHCs) in the rat cochlea and occurs after efferent innervation along the cochlear spiral between P2 and P4. In contrast to OM expression, alphaPV immunoreactivity is expressed in both inner hair cells (IHCs) and OHCs at birth. Following olivocochlear efferent innervation, OHCs demonstrate weak OM immunoreactivity beginning at P5 and diminished alphaPV immunoreactivity after P10. In organ cultures isolated prior to the efferent innervation of OHCs, OM immunoreactivity failed to develop in OHCs, but alphaPV immunoreactivity remained present in both IHCs and OHCs. In contrast, organ cultures isolated after efferent innervation of OHCs show OHCs with low levels of OM immunoreactivity and high levels of alphaPV immunoreactivity. This study suggests that OM and alphaPV are differentially regulated in OHCs during cochlear development. Our findings further raise the possibility that the expression of PV proteins in OHCs may be influenced by efferent innervation.

Animals↗
PubMed2004

Viral interleukin-10 gene therapy to induce tolerance to solid organ transplants in mice.

In this study, a novel gene therapy approach to prolong allograft survival was designed. Autologous (syngeneic) hematopoietic stem cell-enriched bone marrow cells (HSC; lin(-)) engineered with the vIL-10 gene (vIL-10-HSC) were injected (4 to 6 x 10(6) cells, i.v.) into lethally (9.5 Gy) or sublethally (4 Gy) irradiated CBA/J mice 6 weeks prior to allogeneic heart (C57BL/6) transplantation (Tx). Cardiac allograft survival was significantly (P <.004) prolonged in lethally (71 +/- 40 days) and sublethally (114 +/- 15 days) irradiated mice that received vIL-10-HSC compared to controls that received no HSC (11 +/- 1 days), unengineered HSC, or vector-DNA-engineered HSC (12 to 16 days). Tolerant graft histopathology demonstrated mild arteritis/venulitis (grade 0.7) and rejection (grade 1.0). Intragraft expression of costimulatory molecules (B7.1, B7.2), cytokines (IL-2, IL-4, mIL-10, IFN-gamma), and iNOS molecules were markedly lower in tolerant grafts that survived for >100 days; recipient T lymphocytes demonstrated hyporeactivity to donor and third-party antigens in mixed lymphocyte cultures. These findings have important implications and potential therapeutic applications in transplantation and autoimmune diseases.

Animals↗
PubMed2004

Baseline Na-Li countertransport and risk of hypertension in children: a 10-year prospective study in Hanzhong children.

Sodium-lithium countertransport (Na-Li CT) is associated with blood pressure (BP) and in many cross-sectional investigations and some longitudinal studies, essential hypertension has been proposed as a biochemical marker or predictor of hypertension risk in adults. The present study investigated prospectively whether baseline Na-Li CT rate was an index of increased risk of future development of hypertension in children. At baseline visit in 1987 of the Hanzhong Children Hypertension Study comprising 4000 school children aged 5-6 years old, 310 samples were randomly selected for measurement of baseline Na-Li CT rate; we made a 10-year follow-up of them in the same season in 1997. This cohort of children is the sample for analysis in the present report. Baseline Na-Li CT rate was positively correlated to systolic BP (SBP) both in baseline and follow-up (baseline, gamma=0.21, P<0.05; follow-up, gamma=0.32, P<0.01), and positively correlated to diastolic BP (DBP) (gamma=0.20, P<0.05) and body mass index (gamma=0.18, P<0.05) in follow-up examination. Longitudinal analysis of 10-year BP evolution, children in higher baseline Na-Li CT (ie, >260 micromoll RBC/h) had greater BP change than children in lower baseline Na-Li CT (ie, </=260 mumol/l RBC/h) (SBP, 15.8+/-12.9 vs 19.3+/-13.1, DBP 8.8+/-11.2 and 11.3+/-10.6, P<0.05). Multiple logistic regression analysis showed that children in the higher Na-Li CT (>260 mumol/l RBC/h) were associated with approximately 1.5 times greater risk of high BP) in comparison to placement in lower Na-Li CT (</=260 mumol/l RBC/h). Elevated baeline RBC Na-Li countertransport could be a risk predictor predisposing to the development of hypertension in children.

Antiporters↗
PubMed2004

A phase I trial of a Bcl-2 antisense (G3139) and weekly docetaxel in patients with advanced breast cancer and other solid tumors.

PURPOSE: Expression of the Bcl-2 protein confers resistance to various apoptotic signals. G3139 [oblimersen sodium (Genasense)] is a phosphorothioate antisense oligodeoxynucleotide that targets Bcl-2 mRNA, downregulates Bcl-2 protein translation, and enhances the antitumor effects of subtherapeutic doses of docetaxel (Taxotere). PATIENTS AND METHODS: We performed a phase I trial to determine the maximum tolerated dose (MTD) and safety profile of combined therapy with G3139 and weekly docetaxel in patients with advanced Bcl-2-positive solid tumors. Cohorts of three to six patients were enrolled to escalating doses of G3139 and a fixed dose of weekly docetaxel using either of two schedules. In part I, G3139 was administered by continuous infusion for 21 days (D1-22), and docetaxel (35 mg/m2) was given weekly on days 8, 15 and 22. In part II, G3139 was given by continuous infusion for 5 days before the first weekly dose of docetaxel, and for 48 h before the second and third weekly docetaxel doses. For both schedules, cycles were repeated every 4 weeks. RESULTS: Twenty-two patients were enrolled. Thirteen patients were treated on the part I schedule with doses of G3139 escalated from 1 to 4 mg/kg/day. Nine patients were on the part II schedule of shorter G3139 infusion at G3139 doses of 5-9 mg/kg/day. Hematologic toxicities were mild, except for one case of persistent grade 3 thrombocytopenia in part I. The most common adverse events were cumulative fatigue and transaminase elevation, which prevented further dose escalation beyond 4 mg/kg/day for 21 days with the part I schedule. In part II of the study, using the abbreviated G3139 schedule, even the highest daily doses were tolerated without dose-limiting toxicity or the need for dose modification. Objective tumor response was observed in two patients with breast cancer, including one whose cancer previously progressed on trastuzumab plus paclitaxel. Four patients had stable disease. Pharmacokinetic results for G3139 were similar to those of other trials. CONCLUSIONS: G3139 in combination with standard-dose weekly docetaxel was well tolerated. The shortened and intermittent G3139 infusion had less cumulative toxicities and still allowed similar total G3139 delivery as the longer infusion. Further studies should examine the molecular effect of the regimen, as well as clinical activities in malignancies for which taxanes are indicated.

Adult↗