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Biomedical subjects

Wei Shen

Publications and source records attributed to Wei Shen.

At least 109 records · Page 6Linked to original sources
PubMed2003

Percentage body fat ranges associated with metabolic syndrome risk: results based on the third National Health and Nutrition Examination Survey (1988-1994).

BACKGROUND: Increasing attention has focused on the association between body fatness and related metabolic risk factors. The quantitative link between percentage body fat (%BF) and the risk of metabolic syndrome is unknown. OBJECTIVES: The objectives were to determine the risk [odds ratios (ORs)] of metabolic syndrome based on %BF in black and white men and women in the United States and to provide corresponding ranges of %BF associated with a risk equivalent to body mass index (BMI; in kg/m(2)). DESIGN: The subjects were participants in the third National Health and Nutrition Examination Survey and were divided into those with and without the metabolic syndrome. OR equations were derived from logistic regression models for %BF and BMI, with the 25th percentile in the study population as the reference. Ranges were developed by associating %BF with the equivalent risk of metabolic syndrome based on established BMI cutoffs. RESULTS: Four sets (men, women, black, and white) of OR curves were generated for %BF and for BMI by using data from 8259 adults. The ORs for metabolic syndrome were lower in blacks than in whites at any given %BF or BMI. The developed cutoffs for %BF differed between men and women but showed only small race and age effects. A simplified set of sex-specific %BF ranges for the risk of metabolic syndrome were developed. CONCLUSIONS: The risk of metabolic syndrome can be established from measured %BF by using either the developed OR curves or %BF thresholds at traditional BMI cutoffs. This information should prove useful in both clinical and research settings.

Adipose Tissue↗
PubMed2003

Total body protein: a new cellular level mass and distribution prediction model.

BACKGROUND: Protein is an important body component, and the presently accepted criterion method for estimating total body protein (TBPro) mass--in vivo neutron activation (IVNA) analysis--is unavailable to most investigators and is associated with moderate radiation exposure. OBJECTIVE: The objective was to derive a theoretical cellular level TBPro mass and distribution model formulated on measured total body potassium, total body water, and bone mineral and to evaluate the new model with the IVNA method as the criterion. DESIGN: The new model was developed on the basis of a combination of theoretical equations and empirically derived coefficients. TBPro mass estimates with the new model were evaluated in healthy women (n = 183) and men (n = 24) and in men with AIDS (n = 84). Total body nitrogen was measured by IVNA, total body potassium by whole-body (40)K counting, total body water by tritium dilution, and bone mineral by dual-energy X-ray absorptiometry. RESULTS: The group mean (+/- SD) TBPro mass estimates in healthy women and men and men with AIDS (8.2 +/- 0.9, 11.0 +/- 1.8, and 10.5 +/- 1.1 kg, respectively) with the new model were similar to IVNA criterion estimates (8.9 +/- 0.9, 11.1 +/- 1.6, and 10.9 +/- 1.2 kg, respectively). TBPro mass estimates with the new model correlated highly with the IVNA estimates in all subjects combined (r = 0.92, P < 0.001). The new model suggests that the composite TBPro mass within each group consists mainly of cellular protein (75-79%) and, to a lesser extent, protein in extracellular solids (19-23%) and extracellular fluid (approximately 2%). CONCLUSION: The new model provides a non-IVNA approach for estimating protein mass and distribution in vivo.

Absorptiometry, Photon↗
PubMed2003

Tadalafil has no detrimental effect on human spermatogenesis or reproductive hormones.

PURPOSE: We assessed the effects on spermatogenesis of placebo vs 10 or 20 mg tadalafil administered daily for 6 months to healthy men and men with mild erectile dysfunction. MATERIALS AND METHODS: In 2 studies 421 healthy men or men with mild erectile dysfunction who were 45 years or older and met semen criteria derived from WHO reference values were randomized to 6 months of treatment with placebo (101) or 10 mg tadalafil (103), or to placebo (106) or 20 mg tadalafil (111). Semen samples and serum for reproductive hormones (testosterone, luteinizing hormone and follicle-stimulating hormone) were collected at baseline, after 3 months and at the end of treatment. RESULTS: Tadalafil had no adverse effects on spermatogenesis, as assessed by sperm concentration, sperm count per ejaculate, percent sperm motility, normal morphology or serum reproductive hormones. Tadalafil was well tolerated. Common adverse events were headache, dyspepsia and back pain. CONCLUSIONS: Chronic daily administration of tadalafil at doses of 10 and 20 mg for 6 months had no adverse effects on spermatogenesis or on reproductive hormones in men older than 45 years.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed2003

Inhibitive effect of cordyceps sinensis on experimental hepatic fibrosis and its possible mechanism.

AIM: To investigate the inhibitive effect and its possible mechanism of Cordyceps Sinensis (CS) on CCl(4)-plus ethanol-induced hepatic fibrogenesis in experimental rats. METHODS: Rats were randomly allocated into a normal control group, a model control group and a CS group. The latter two groups were administered with CCl(4) and ethanol solution at the beginning of the experiment to induce hepatic fibrosis. The CS group was also treated with CS 10 days after the beginning of CCl(4) and ethanol administration. All control groups were given corresponding placebo at the same time. At the end of the 9th week, rats in each group were humanely sacrificed. Blood and tissue specimens were taken. Biochemical, radioimmunological, immunohistochemical and molecular biological examinations were used to determine the level change of ALT, AST, HA, LN content in serum and TGFbeta(1), PDGF, collagen I and III expression in tissue at either protein or mRNA level or both of them. RESULTS: As compared with the model control group, serum ALT, AST, HA, and LN content levels were markedly dropped in CS group (86.0+/-34.4 vs 224.3+/-178.9, 146.7+/-60.2 vs 272.6+/-130.1, 202.0+/-79.3 vs 316.5+/-94.1 and 50.4+/-3.0 vs 59.7+/-9.8, respectively, P<0.05). Tissue expression of TGFbeta(1) and its mRNA, collagen I mRNA were also markedly decreased (0.2+/-0.14 vs 1.73+/-1.40, 1.68+/-0.47 vs 3.17+/-1.17, 1.10+/-0.84 vs 2.64+/-1.40, respectively, P<0.05). More dramatical drop could be seen in PDGF expression (0.87+/-0.43 vs 1.91+/-0.74, P<0.01). Although there was no statistical significance, it was still strongly suggested that collagen III mRNA expression was also decreased in CS group as compared with model control group (0.36+/-0.27 vs 0.95+/-0.65, P=0.0615). In this experiment, no significant change could be found in PDGF mRNA expression between two groups (0.35+/-0.34 vs 0.70+/-0.46, P>0.05). CONCLUSION: Cordyceps sinensis could inhibit hepatic fibrogenesis derived from chronic liver injury, retard the development of cirrhosis, and notably ameliorate the liver function. Its possible mechanism involves inhibiting TGFbeta(1) expression, and thereby, down regulating PDGF expression, preventing HSC activation and deposition of procollagen I and III.

Animals↗
PubMed2003

[Influence of Cordyceps sinensis on pancreatic islet beta cells in rats with experimental liver fibrogenesis].

OBJECTIVE: To investigate the effect of Cordyceps sinensis (CS) on pancreatic islet B cells of experimental hepatic fibrogenesis rats. METHODS: Rats were randomly allocated into three groups: normal group, model group and CS group. The rats in the latter two groups were administered with CCl(4) solution to induce liver fibrosis, the CS group was also treated with CS 10 days after the beginning of CCl(4) administration. Rats in normal group were sacrificed at the beginning of the experiment, while the rats in the other two groups were sacrificed randomly at the end of the third and sixth weeks. The rats' islets were isolated and cultured in vitro, then the basal insulin level of the islets and the serum level of insulin were determined by radioimmunological assay. RESULTS: It seemed no change that the levels of serum insulin and basal insulin between the model group and the normal group at the third week. But at the sixth week, both insulin levels in the model group were higher than those in the normal group (52.6 mU/L2.5 mU/L vs 23.7 mU/L 2.3 mU/L, q=13.01, p<0.05; 52.94muU/ml 13.12muU/ml vs 35.16muU/ml 5.64muU/ml, q=10.06, p<0.01). No significant change could be seen in the serum levels of insulin between the CS group and the model group at the third and sixth weeks. But the basal insulin levels in the CS group were apparently higher than those in the model group at the third and sixth weeks (156.63muU/ml 6.57muU/ml vs 39.64muU/ml 3.95muU/ml, q=66.94, p<0.001; 140.44muU/ml 38.53muU/ml vs 52.94muU/ml 13.12muU/ml, q=12.98, p<0.01). CONCLUSION: Cordyceps sinensis can increase the basal insulin level of the islets in CCl(4)-induced liver fibrosis rats.

Animals↗
PubMed2003

The impact of incident vertebral and non-vertebral fragility fractures on health-related quality of life in established postmenopausal osteoporosis: results from the teriparatide randomized, placebo-controlled trial in postmenopausal women.

OBJECTIVE: To report the combined impact of both vertebral and non-vertebral fractures on decreased health-related quality of life (HRQOL) in postmenopausal women (mean age 70.7) with osteoporosis who participated in a clinical trial to examine the anti-fracture efficacy of teriparatide [rhPTH(1-34)] injection. METHODS: Patients were randomly assigned to 1 of 3 study arms: placebo, 20 micro g or 40 micro g of teriparatide by daily self-injection. All patients received daily calcium (1000 mg) and vitamin D (400-1200 U) supplements. Patients were followed for a median of 21 months. Incident vertebral fractures were assessed by lateral spinal radiograph. Incident non-vertebral fractures were ascertained by patient self-report and verified by a review of radiological reports. HRQOL was assessed at baseline and annually until study termination using the Osteoporosis Assessment Questionnaire (OPAQ), a validated disease-targeted instrument. RESULTS: Of the 365 women in the HRQOL sub-study, 53 had an incident vertebral or non-vertebral fracture during the study period. Compared to women without incident fractures, women who fractured reported significant declines in physical functioning, emotional status, and symptoms (all p < 0.05). Similarly, when analysis was limited to patients with significant loss in HRQOL, patients with incident fracture accounted for a greater proportion of those patients with decreased physical function, emotional status, and increased symptoms (all p < 0.05). CONCLUSION: Our results confirm and extend previous findings to show that a composite endpoint of incident vertebral and non-vertebral fractures in women with postmenopausal osteoporosis was associated with significant decreases in HRQOL.

Aged↗
PubMed2003

[Establishment of BAC mediated transgenic mice containing 97 kb beta-globin gene cluster].

OBJECTIVE: To delete IL-11 receptor alpha chain gene from the Bacterial Artificial Chromosome (BAC) chimeric DNA by RecA protein mediated homologous recombination method and establish the transgenic mice model containing whole beta-globin gene cluster. METHODS: Two 500 bp homologous sequences (A and B) located at the upstream and downstream of IL-11 receptor alpha chain gene respectively were cloned into the Hind III and Xba I sites of pBV vector, then the 1 kb A + B fragment was recovered from the building vector and inserted into the Sal I site of the shuttle vector pSV-RecA. After transforming the shuttle vector into the competent DH10B E. Coli containing BAC DNA, the IL-11 receptor alpha chain gene was finally deleted from the BAC DNA through chloramphenicol positive selection and fusaic acid negative selection. The new BAC clone was characterized by Pulse Field Gel Electrophoresis (PFGE). Then, we microinjected the linearized and purified BAC DNA into the mouse fertilized eggs and prepared the transgenic mice. RESULTS: By RecA protein mediated homologous recombination method, we deleted the IL-11 receptor alpha chain gene from the BAC DNA containing the complete beta-globin Gene Cluster and established 3 respective transgenic mice lines. CONCLUSION: Human beta-globin gene cluster in the transgenic mice mediated by new BAC expresses in a correct mode and level as compared with previous transgenic mice.

Animals↗
PubMed2003

[Serological characteristics of a hepatitis E outbreak].

OBJECTIVE: To look into the serological characteristics of a hepatitis E outbreak. METHODS: Sera from the first five patients with acute icteric hepatitis who developed the disease successively within ten days and the 1,675 employees routinely having their lunch in a dining hall of a department (outbreak population) were examined for anti.HEV IgM and IgG at 26th days after the outbreak, and the 883 employees of a neighboring department not having their lunch in the hall were selected as control (control population). RESULTS: The five patients were all positive for anti-HEV IgM and IgG. The positive rates of anti-HEV IgM and IgG in outbreak population were 8.7% and 38.4% respectively, both significantly higher than those in control population which were only 0.1% and 28.6%. The numbers with abnormal ALT in the 145 individuals with anti-HEV IgM(+) of outbreak population were significantly higher than those in the IgM(-) individuals of the same group as well as in control, while the abnormal ALT ratio in the IgM(-) individuals of the outbreak was not higher than that in control. The results from the four patients' serial sera showed that the anti-HEV IgM titers declined gradually and were undetectable at about 4th month after infection, and the IgG titers increased to peak in about 2-3 months after infection, then declined very slowly. The mean IgG titer of the anti-HEV IgM(+) individuals was significantly higher than that of the IgM(-) but IgG(+) individuals in outbreak population, and the latter was significantly higher than the IgG(+) individuals in control, which suggested that the post-infection individuals' immunities to HEV were boosted during the outbreak. There was no difference between sex or age groups for the anti-HEV IgM(+) ratio, but the abnormal ALT was much more frequent in the anti-HEV IgM(+) male than in the female, and no difference was observed between age groups. CONCLUSION: The pathogen of the outbreak of acute icteric hepatitis was hepatitis E virus and associated with food intake. Anti-HEV IgM and IgG were used not only for diagnosis of hepatitis E but also for surveilance in mass population. The attack risk was not associated with age or sex, but the abnormal ALT was much more frequent fresh infectors in male.

Adult↗
PubMed2003

[Genetic co-adaptability among structural genes under the condition of genetic disequilibrium].

With the technology of PAGE,the genetic polymorphism of blood protein and enzyme was investigated,and genetic co-adaptability among structural genes was studied in three goat populations(147 goats) including Chaidamu goat(CS), Chaidamu Cashmere goat(CRS) and Liaoning Cashmere goat(LRS) in Qinghai Province, China. The results were showed that the genetic disequilibrium of 10 locus combinations was found among 45 locus combinations in the three goat populations,and these genetic disequilibria were caused only by the difference of genetic co-adaptability among genes,because there didn't exist the linkage disequilibrium among non-allelic genes. The genetic disequilibrium including the difference of genetic co-adaptability between non-allelic genes was only found at Tf-P(A-3) locus combinations in LRS population,the other ones were all caused by the genetic disequilibrium at a single locus. The difference of genetic co-adaptability of LAP-EsD locus combinations could be messaged among different populations.

English Abstract↗
PubMed2003

[Production of mammary gland bioreactor by gene targeting of somatic cells].

Producing mammary gland bioreactor showed great advantage over many years, but the level of transgenic expression was low in transgenic animals and the diversity was more great because of the position effect of transgene and the artificial recombination of the gene elements. Gene targeting based on the principle of gene homologous recombination had been studied and applied, because the transgene could be integrated precisely in the chromosome. This review summary the current status of producing mammary gland bioreactor by the technology of gene targeting and nuclear transfer using the somatic cell lines. These aspects were discussed, including the characteristic and difficulties of gene targeting, the strategies to improve the efficiency of gene targeting, the different features of between the strategy of promoter-trap and the Cre-LoxP system, etc; for the others, how to select the cell lines with the different strategies of gene targeting, how to raise the times of cell lines that was cultured after the gene targeting. Somatic cell nuclear transfer offers new and exciting opportunities in the areas of the gene targeting. However, the field as a whole is still difficult and complex. In this paper, we described recent advances and novel approaches, which resulted in progress during the last year. Key problems hindering further progress are addressed, for example, how to increase the efficiency of nuclear transfer. With the technology of gene targeting and nuclear transfer, it should provide a general way to produce specific genetic changes in several mammalian species. We are clearly at the dawn of a new era in mammalian genetic technology.

Animals↗
PubMed2002

Field testing of Schistosoma japonicum DNA vaccines in cattle in China.

Vaccines are needed to reduce the zoonotic reservoir of Schistosoma japonicum infection in bovines in China. We have developed two experimental DNA vaccines and have already shown these to be capable of inducing partial protection in water buffalo naturally exposed to the risk of S. japonicum infection in the field. We now report a similar field trial in cattle, the other major bovine reservoir host species in China. Groups of cattle were vaccinated with the VRSj28 vaccine or the VRSj23 vaccine, or, to test whether protection could be enhanced by combination vaccination, with both these DNA vaccines together. After vaccination, the cattle were exposed to natural infection in the field for a period of 54 days. Worm and egg counts carried out at the end of the experiment showed that each of the vaccine groups showed partial resistance, and that combined vaccination was not more effective than vaccination with the individual plasmids.

Animals↗
PubMed2002

Expression of creatine kinase isoenzyme genes during postnatal development of rat brain cerebellum: evidence for transcriptional regulation.

Transcription and accumulation of brain-type creatine kinase (CKB) mRNA and its protein was examined during postnatal development of rat brain cerebellum, the brain region containing highest CKB mRNA in the adult. CKB protein was extremely low at day 1, increased about 10-fold until week 4 and remained constant until week 10. This time course was paralleled by cerebellar CKB mRNA, which was also extremely low at day 1 and increased 5-fold during the first 3 weeks and then remained constant. High levels of CKB protein were also detected in cultured primary cerebellar granular neurons. Nuclear run-on assays directly showed that CKB mRNA accumulation during postnatal cerebellar development was due to increased transcription. When compared with cerebrum and whole brain, cerebellar CKB mRNA accumulation during postnatal development was temporally delayed. Analysis of myocyte enhancer factor (MEF)-2 and Sp1, factors known to initiate or sustain CKB transcription in tissues other than brain, revealed that MEF-2 in cerebellum was low at week 1 but increased 3.5-fold by week 7, while Sp1 remained unchanged. The increase in CKB protein during cerebellar postnatal development was coincident with that of the ubiquitous mitochondrial CK protein and mRNA, indicating that a functional phosphocreatine energy shuttle probably exists for efficient ATP regeneration in the cerebellum. This should be beneficial for the many energy-demanding requirements during cerebellar development, as indicated by the observed temporal co-expression of CKB with myelin basic protein, which is involved in axon myelination by oligodendrocytes.

Animals↗
PubMed2002

Foxa3 (HNF-3gamma) binds to and activates the rat proglucagon gene promoter but is not essential for proglucagon gene expression.

Members of the Forkhead box a (Foxa) transcription factor family are expressed in the liver, pancreatic islets and intestine and both Foxa1 and Foxa2 regulate proglucagon gene transcription. As Foxa proteins exhibit overlapping DNA-binding specificities, we examined the role of Foxa3 [hepatocyte nuclear factor (HNF)-3gamma] in control of proglucagon gene expression. Foxa3 was detected by reverse transcriptase PCR in glucagon-producing cell lines and binds to the rat proglucagon gene G2 promoter element in GLUTag enteroendocrine cells. Although Foxa3 increased rat proglucagon promoter activity in BHK fibroblasts, augmentation of Foxa3 expression did not increase proglucagon promoter activity in GLUTag cells. Furthermore, adenoviral Foxa3 expression did not affect endogenous proglucagon gene expression in islet or intestinal endocrine cell lines. Although Foxa3(-/-) mice exhibit mild hypoglycaemia during a prolonged fast, the levels of proglucagon-derived peptides and proglucagon mRNA transcripts were comparable in tissues from wild-type and Foxa3(-/-) mice. These findings identify Foxa3 as a member of the proglucagon gene G2 element binding-protein family that, unlike Foxa1, is not essential for control of islet or intestinal proglucagon gene expression in vivo.

Animals↗
PubMed2002

Efficacy and safety of tadalafil for the treatment of erectile dysfunction: results of integrated analyses.

PURPOSE: We conducted integrated analyses of the efficacy and safety of tadalafil, a potent, selective phosphodiesterase 5 inhibitor, for the treatment of erectile dysfunction. MATERIALS AND METHODS: A total of 1,112 men with a mean age of 59 years (range 22 to 82) and mild to severe erectile dysfunction of various etiologies were randomized to placebo or tadalafil, taken as needed without food or alcohol restrictions, at fixed daily doses of 2.5 mg, 5 mg, 10 mg, or 20 mg up to a maximum of once daily [DOSAGE ERROR CORRECTED] in 5 randomized, double-blind, placebo controlled trials lasting 12 weeks. The 3 co-primary outcomes were changes from baseline in the erectile function domain of the International Index of Erectile Function and the proportion of "yes" responses to questions 2 and 3 of the Sexual Encounter Profile. Additional efficacy instruments included a Global Assessment Question. RESULTS: Compared with placebo, tadalafil significantly enhanced all efficacy outcomes. Patients receiving 20 mg. tadalafil experienced a significant mean improvement of 7.9 in International Index of Erectile Function erectile function domain score from baseline (p <0.001 versus placebo), 75% of intercourse attempts (Sexual Encounter Profile question 3, a secondary efficacy outcome) were successfully completed (p <0.001 versus placebo) and 81% reported improved erections at end point compared with 35% in the control group (p <0.001). Tadalafil was consistently efficacious across disease severities and etiologies, as well as in patients of all ages. Tadalafil was well tolerated, and headache and dyspepsia were the most frequent adverse events. CONCLUSIONS: Tadalafil was effective and well tolerated in this patient population.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed2002

[Surgical approach in plastic of shortened lower limb].

OBJECTIVE: To introduce a new surgical approach to rectify the shortened lower limbs. METHODS: From March 1985 to October 2000, 288 cases of shortened lower limbs were treated and reviewed. Closed fracture at the metaphysis was made by a self-made "needle saw", and then the "multiple-plane and double-track elongation instrument" was adopted to elongate the fractured bone. There were totally 161 cases of male and 127 cases of female included, with average age 21.3 years old, ranging from 12 to 29 years old, among which there were 268 cases elongated at the proximal metaphysis of the tibia, 16 cases at the distal femur and 4 cases at the distal tibia. All of the cases were followed up for 6 to 8 months before clinical evaluation. RESULTS: The lower limbs in 288 cases were elongated for 3.0 to 11.5 cm in 24 to 96 days, averaging 47 days, which fulfilled pre-operative plan. In the second week after the operation, new calculus and periosteum formed obviously in the gap between the fractured parts, and in 6 to 8 months bone union was observed at the fractured site in all cases. There was no nerve or blood vessel injury, or non-union of the metaphysis fracture. The function of the manipulated knee joints and ankle joints recovered well. CONCLUSION: It is a practical and safe surgical option to rectify the shortened lower limbs by closed fracture at the metaphysis, followed by elongation of the fractured bone, without any complication such as non-union or atrophy of manipulated bone, and with no need of internal fixation or bone grafting.

Adolescent↗