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Biomedical subjects

J Wu

Publications and source records attributed to J Wu.

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

Signal transducer and activator of transcription 6 gene G2964A polymorphism and inflammatory bowel disease.

Signal transducer and activator of transcription 6 (STAT6) is a key transcription factor involved in interleukin 4 (IL-4) and IL-13-mediated Th2 response. The STAT6 gene is located on chromosome 12q13.3-14.1 (IBD2 region) and is therefore a positional and functional candidate gene for study in inflammatory bowel disease. We investigated the G2964A polymorphism in the 3' untranslated region of the STAT6 gene in Dutch patients with inflammatory bowel disease and healthy controls. The G2964A polymorphism in the STAT6 gene was genotyped in 141 unrelated Dutch Caucasian patients with ulcerative colitis, 183 patients with Crohn's disease and 173 healthy individuals by PCR and the amplification-created restriction site method. Patients with Crohn's disease were classified according to the Vienna classification and the patients with ulcerative colitis were classified with the age at onset, extent of disease and colectomy. We did not find significant differences in genotype and allele frequencies of the G2964A polymorphism in the STAT6 gene between ulcerative colitis, Crohn's disease and healthy controls. Subgroups of the patients with Crohn's disease classified according to the Vienna classification and those with ulcerative colitis classified according to age of onset, disease extension and colectomy did not differ in the distribution of this polymorphism. The STAT6 G2964A gene polymorphism is not involved in the overall susceptibility or in determining the phenotype of IBD.

Adult↗
PubMed2003

Automated quantification and reconstruction of collagen matrix from 3D confocal datasets.

The geometrical structure of fibrous extracellular matrix (ECM) impacts on its biological function. In this report, we demonstrate a new algorithm designed to extract quantitative structural information about individual collagen fibres (orientation, length and diameter) from 3D backscattered-light confocal images of collagen gels. The computed quantitative data allowed us to create surface-rendered 3D images of the investigated sample.

Animals↗
PubMed2003

In vitro development of marmoset monkey oocytes by pre-antral follicle culture.

A technique for in vitro maturation of oocytes from small ovarian follicles of marmoset monkeys (Callithrix jacchus) has been developed. We employed a two-step culture system for primary follicles (45-85 microm) and a one-step culture technique for secondary follicles (>85 microm). The two-step technique started with the culture of stromal tissue fragments for 2 days. Thereafter, mechanically isolated follicles were transferred to a culture system where they attached to the culture surface and grew for up to a further 12 days. Significant growth of the small follicles and their oocytes was only achieved with gonadotrophins in the medium. Oocytes with a mean diameter of 39 microm from follicles <85 microm reached a mean diameter of 90 microm by the end of the two-step culture. After in vitro maturation, 19% of oocytes from these follicles had progressed to the germinal vesicle breakdown (GVBD). Follicles between 85 and 170 microm in diameter were isolated from the stroma and placed directly in the culture. Oocytes from these follicles had a mean diameter of 64 microm. The maximum size the oocytes reached in culture was related to the age of the females (pre-pubertal females: 102 +/- 1.3 microm; adults: 96 +/- 1.4 microm). Twenty-seven per cent of oocytes from pre-pubertal ovaries achieved GVBD and nearly two-thirds of these progressed to polar body stage. From adult ovaries, only 12% progressed to GVBD and one-third of these to polar body stage. It is possible to develop mature oocytes in vitro from marmoset secondary pre-antral follicles (>85 microm). From primary follicles, although near full size oocytes were developed, maturation capacity was incomplete.

Age Factors↗
PubMed2003

Anti-hyperglycemic effects of ginseng: comparison between root and berry.

Previous studies demonstrated that both ginseng root and ginseng berry possess anti-diabetic activity. However, a direct comparison between the root and the berry under the same experimental conditions has not been conducted. In the present study, we compared anti-hyperglycemic effect between Panax ginseng root and Panax ginseng berry in ob/ob mice, which exhibit profound obesity and hyperglycemia that phenotypically resemble human type-2 diabetes. We observed that ob/ob mice had high baseline glucose levels (195 mg/dl). Ginseng root extract (150 mg/kg body wt.) and ginseng berry extract (150 mg/kg body wt.) significantly decreased fasting blood glucose to 143 +/- 9.3 mg/dl and 150 +/- 9.5 mg/dl on day 5, respectively (both P < 0.01 compared with the vehicle). On day 12, although fasting blood glucose level did not continue to decrease in the root group (155 +/- 12.7 mg/dl), the berry group became normoglycemic (129 +/- 7.3 mg/dl; P < 0.01). We further evaluated glucose tolerance using the intraperitoneal glucose tolerance test. On day 0, basal hyperglycemia was exacerbated by intraperitoneal glucose load, and failed to return to baseline after 120 min. After 12 days of treatment with ginseng root extract (150 mg/kg body wt.), the area under the curve (AUC) showed some decrease (9.6%). However, after 12 days of treatment with ginseng berry extract (150 mg/kg body wt.), overall glucose exposure improved significantly, and the AUC decreased 31.0% (P < 0.01). In addition, we observed that body weight did not change significantly after ginseng root extract (150 mg/kg body wt.) treatment, but the same concentration of ginseng berry extract significantly decreased body weight (P < 0.01). These data suggest that, compared to ginseng root, ginseng berry exhibits more potent anti-hyperglycemic activity, and only ginseng berry shows marked anti-obesity effects in ob/ob mice.

Animals↗
PubMed2003

Evaluation of three concentrations of tebufenpyrad for the control of Varroa destructor (Acari: Varroidae).

We evaluated three concentrations of tebufenpyrad (17.5, 15 and 12.5%) in strip formulations for controlling varroa mites, Varroa destructor Anderson and Trueman (2000), in honey bee colonies. We also included colonies treated with Apistan, CheckMite+, and untreated colonies in our evaluation. The three concentrations we evaluated reduced varroa populations but also reduced the amount of brood and adult bees when compared with untreated colonies and colonies treated with Apistan or CheckMite+. Alternative delivery methods, lower concentrations of tebufenpyrad, and the evaluation of related compounds are logical next steps in evaluating the varroacidal potential of tebufenpyrad and related compounds.

Animals↗
PubMed2003

Expression of a novel factor, short-type PB-cadherin, in Sertoli cells and spermatogenic stem cells of the neonatal rat testis.

In the rodent testis, contact-mediated interactions between gonocytes, or neonatal stem cells, and Sertoli cells are critical for development. Previously, we showed that the neural cell adhesion molecule (NCAM) serves as a Sertoli cell-gonocyte attachment factor in neonates. Its expression decreases dramatically by 1 week of age and eventually disappears in vivo, and appears to be down-regulated by thyroid hormone (tri-iodothyronine (T(3))). In this study, we used a cDNA microarray to screen for additional adhesion factors which might be important in testes of developing rats and detected expression of a novel factor, short-type PB-cadherin (STPB-C). Next, RT-PCR was used to generate cDNA for STPB-C from total RNA isolated from co-cultures, cDNA was cloned into pPCR-Script Amp SK(+) cloning vector, and plasmid DNA was isolated and sequenced to confirm the fidelity of the STPB-C cDNA portion of the plasmid. In situ hybridization analyses of testicular sections indicated that STPB-C expression in neonates is localized in the cytoplasm of many, but not all, gonocytes and in the cytoplasm of most of the surrounding Sertoli cells. Parallel hybridizations carried out on co-cultures also demonstrated a strong cytoplasmic signal in some gonocytes and in the great majority of the Sertoli cells of the underlying monolayer. With Northern analyses we found that STPB-C is expressed in vivo at high levels between days 1 and 5, with a subsequent large drop by day 10 and thereafter, suggesting that its expression may be associated with Sertoli or germ cell differentiation. Subsequent analyses of co-cultures exposed under a variety of conditions to T(3) suggest that, unlike NCAM, STPB-C is not regulated by this hormone. Next, we studied production of STPB-C protein by using an antiserum recognizing a peptide sequence unique to this factor in Western blotting and in immunolocalization. Signal was detected both intracellularly and at cell surfaces in most Sertoli cells and many gonocytes, although many of the latter cell type were also found to be negative for the protein, suggesting a potential role for STPB-C in survival and further development of some of these germ cells from which all subsequent spermatogenic cells originate.

Animals↗
PubMed2003

Pregnancy-associated breast cancer: a case control and long-term follow-up study in China.

Pregnancy associated (PA) breast cancer is defined when diagnosed during pregnancy or within one year afterwards. To analyze the prognostic factors related to this disease and assess the impact of pregnancy on breast cancer patients, 88 PA breast cancer patients initially treated in the Shanghai Cancer Hospital from 1957 to 1990 were reviewed. A non-PA group including 176 patients individually well matched to the PA group was also analyzed. Univariate analysis suggested prognostic value for clinical tumor size, TNM stage, and breast feeding time among the classic prognostic factors, pregnancy associated factors and treatment modalities were evaluated. Multivariate analysis demonstrated clinical tumor size, TNM stage and axillary lymph node metastasis as independent prognostic factors. Compared with the non-PA group, the PA group was significantly correlated with delay at diagnosis, large size of the tumor, late TNM stage, extension to the skin or chest wall and administration with oophorectomy. The overall survival rates of 5-year, 10-year and 20-year were 40.39%, 36.29% and 30.70%, respectively, which were worse than those in the non-PA group, but did not reach a significant difference (p=0.0536). We are conducting further basic research to analyze the biologic characteristics of PA breast cancer.

Adult↗