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Jie Tang

Publications and source records attributed to Jie Tang.

68 records · Page 4Linked to original sources
PubMed2003

Evaluation of the effect of protamine on human prostate carcinoma PC-3m using contrast enhanced Doppler ultrasound.

PURPOSE: We evaluated the ability of contrast enhanced Doppler ultrasound (CEDU) to demonstrate changes in tumor vascularity during angiogenesis inhibitive therapy in PC-3m human prostate carcinoma. MATERIALS AND METHODS: Pieces of human prostate carcinoma PC-3m tumor (Institute of Urology, Beijing University, Beijing, People's Republic of China) were transplanted subcutaneously into 48 male BALB/C nude mice (Center of Animal Quarantine, Beijing, People's Republic of China). Protamine (Shanghai Biochemistry Pharmaceutical Co., People's Republic of China) was injected subcutaneously as an angiogenesis inhibitor. The animals were randomly divided into 3 groups according to protamine dose. The color flow signal-pixel rate (SPR) of the images was calculated using the number of pixels showing color Doppler signals as a ratio of the total number of pixels covering the lesion. RESULTS: The SPR of the high and low dose groups were significantly lower than that of the control group (p <0.01). Mean SPR +/- SD in the 3 groups was 0.09 +/- 0.05, 0.11 +/- 0.05 and 0.22 +/- 0.10, respectively. SPR correlated significantly with microvessel density (r = 0.86 to 0.94, p <0.01). CONCLUSIONS: CEDU can effectively reveal the change in vascularity in a tumor that was treated with protamine. In addition to microvessel density, CEDU may become one of several independent prognostic indexes of angiogenesis inhibitor therapy.

Angiogenesis Inhibitors↗
PubMed2003

[Study on sperm quality of the soldiers influenced by reinforced training].

OBJECTIVES: To investigate the correlation between abnormal sperm parameters and reproductive hormones and reinforced training. METHODS: Epidemic investigation were done between two different groups by determining endocrine hormone and standard clinical sperm analysis. RESULTS: Comparison between reinforced training group and non-training group showed decreased sperm velocity but no change on sperm moving form, increased teratism sperm percentage but no change on sperm number, decreased plasma testosterone but no change on LH. CONCLUSIONS: Reinforced training has correlation with weak part of sperm parameter analysis and reproductive hormones.

Humans↗
PubMed2003

[Distribution characteristics of metabolites of BHC and derivatives of DDT from the agricultural runoff in the western Songnen plain].

Through analyzing the contents of metabolites of BHC and derivatives of DDT in the runoff from paddy and corn land in the Western Songnen Plain, it was found that the contents of BHC and DDT were very lower and beta-BHC, which accounted for 73.5%-99.5% of the contents of BHC, was the main metabolite of BHC in the runoff. Among the derivatives of DDT, only p, p-DDT was detected out. Moreover, dissolved form was the dominant species of metabolites and derivatives, but the particles size was one of the important factors which affect on the contents of BHC and DDT in runoff. The ecological risk of DDT in suspended substance of runoff from farmland was lower and BHC had potential risk in the region.

Agriculture↗
PubMed2003

[Study on sperm quality of males living in cold area].

OBJECTIVE: To investigate the effects on male reproductive function working under cold area. METHODS: After on site investigation, advanced molecular lab analysis-single-cell gel electrophoresis (SCGE) and sperm chromatin structure assay (SCSA) which are combined with semen routine analysis were used to evaluate semen quality and sperm sub-clinical injury. RESULTS: Semen routine analysis showed that the semen parameters of the males working in cold area were within normal range, but level I comet cell percentage in SCGE increased significantly, which was 4.4%, compared to the contrast group (1.9%) with significant difference. During sperm chromatin structure assay parameters, comp alpha t increased, with an average value of 22.26%. The two kinds of results both showed single and double strand breakages in sperm. CONCLUSION: Long-term exposure to cold could induce sperm DNA injury, but not affect sperm quality. The results suggested that it was important to reinforce the reproductive care in males working in cold areas.

Adult↗
PubMed2003

[Analysis of correlation between parameters of sperm chromatin structure assay and semen routine analysis].

OBJECTIVES: To analysis the correlation between parameters of sperm chromatin structure assay(SCSA) and semen routine analysis, and to discuss the reliable methods of semen quality evaluation. METHODS: Five hundred and eleven semen samples were detected to analyse the mutiple-parameter correlation between results of SCSA (COMP alpha t) and semen routine analysis. RESULTS: The parameters that have low-level positive correlation(r: 0.10-0.30) with denatured sperm percentage(COMP alpha t) were viscosity, ejaculation interval, abnormal sperm ratio, concentration of grade c sperm; those having low-level negative correlation(r: -0.30(-)-0.10) were VDL, VSL and VAP; those having mid-level positive correlation (r: 0.30-0.70) were sperm concentration, percentage of grade d sperm; those having mid-level negative correlation (r: -0.70(-)-0.30) were MAD, percentage of grade a sperm and survival rate. CONCLUSIONS: Flow cytometry can be used to evaluate the percentage of denatured or injured sperm rapidly, correctly and simply. The result (COMP alpha t) correlates partly with semen parameters, and it is not a conclusively parameter compared with routine semen analysis. It is important to use SCSA to evaluate productivity under the above situation.

Adult↗
PubMed2003

[Evaluation of radiation damage to the sperm DNA of radar operators].

OBJECTIVE: To evaluate the inflicted by radar electromagnetic radiation to the sperm DNA of radar operators. METHODS: Sperm concentration, viability, motility, sperm abnormality were determined by routine sperm analysis and sperm chromatin structure assay (SCSA) in the highly exposed group(n = 88), lowly exposed group(n = 143) and control group(n = 39). RESULTS: Sperm motility, viability of the highly exposed group reduced compared with that of the lowly exposed group and control group, while sperm abnormality increased. The COMP alpha reduction of the highly exposed group indicated that the highly exposed group had a medium fertility potential. The multifactor variable analysis showed that daily working time was a dangerous factor in sperm abnormality and abstinence time was a dangerous factor in the parameter of SCSA. CONCLUSIONS: Radar radiation inflicts damage to male reproduction system and it is important to take protective measures.

Adolescent↗
PubMed2003

[Expression of vascular endothelial growth factor during mandibular distraction osteogenesis in rabbits].

OBJECTIVE: To investigate the expression pattern of vascular endothelial growth factor (VEGF) in the distracted callus during mandibular osteodistraction. METHODS: Bilateral mandibular osteotomies were performed in 12 rabbits. 3 rabbits were sacrificed respectively at 0, 7, 14 and 28 days after completion of distraction. The newly formed calluses were harvested and processed for histology and immunohistochemistry of VEGF. RESULTS: Intense angiogenesis was observed in the regenerated callus after mandibular lengthening, and positive staining for VEGF was mainly noted in vascular endothelial cells and the active osteoblasts. CONCLUSIONS: Mechanical strain created by distraction led to angiogenesis in distraction gap. VEGF may play a critical role in angiogenesis and subsequent osteogenesis during mandibular lengthening.

Animals↗
PubMed2003

[The effect of overtraining on human sperm chromatin structure].

OBJECTIVE: To identify the effects of overtraining on human sperm DNA. METHODS: Molecular epidemiological investigation of 249 men from different groups (training and non-training) was carried out by using flow cytometer to detect the integrity and damage of in situ DNA of sperm nucleus, and sperm chromatin structure assay was performed. RESULTS: The average COMPalpha(t) in training group was 11.02% while that in control group was 5.90% (P < 0.01). COMPalpha(t) was significantly correlated with sperm activity (r = 0.41, P < 0.05). CONCLUSION: Overtraining could induce sperm DNA injury and affect sperm activity, thus to decrease the potentiality of reproduction.

Adult↗
PubMed2002

Nerve growth factor-mediated increases in protein methylation occur predominantly at type I arginine methylation sites and involve protein arginine methyltransferase 1.

Nerve growth factor (NGF)-specific signal transduction leads to changes in protein methylation during neuronal differentiation of PC12 cells (Cimato et al. [1997] J. Cell Biol. 138:1089-1103). In the present work, we demonstrate that, among NGF-regulated proteins, arginine methylation is more prevalent than carboxylmethylation. Type I protein arginine methyltransferase (PRMT) activity produces asymmetric dimethylation of the terminal guanidinonitrogen of arginines in substrate proteins, particularly glycine and arginine-rich (GAR) segments of proteins. Several GAR peptides were used to assay for methyltransferase activity and to compete with endogenous cellular proteins for the PRMT activity in PC12 cell extracts. Peptides derived from fibrillarin and nucleolin, as well as a synthetic GAR peptide containing a repetitive GRG motif, are each extremely effective at blocking in vitro methylation of the NGF-regulated PC12 cell methylated proteins. Myelin basic protein, a substrate for type II PRMT, selectively inhibits a 45 kDa protein but is a much less effective inhibitor of total methylation at an equimolar concentration. In addition, the fibrillarin- and nucleolin-derived peptides were used to detect elevated PRMT activity in homogenates of NGF-treated PC12 cells. Finally, immunoprecipitation of PRMT1 from PC12 cells provides the first demonstration of an NGF-activated methyltransferase and implicates PRMT1 in NGF signal transduction.

Animals↗
PubMed2002

Angiotensin II activation of the JAK/STAT pathway in mesangial cells is altered by high glucose.

BACKGROUND: Both high glucose (HG) and angiotensin II (Ang II) causes glomerular mesangial cell (GMC) growth and increased synthesis of matrix proteins like collagen IV contributing to diabetic nephropathy. We have recently found that exposure of vascular smooth muscle cells to HG augments the Ang II activation of the growth promoting JAK/STAT pathway. We hypothesized that Ang II activation of the JAK/STAT pathway is altered by HG in GMC, and that this pathway might be linked to the Ang II-induced growth and overproduction of collagen IV in GMC in HG conditions. METHODS: GMC were cultured under normal glucose (NG; 5.5 mmol/L) and HG (25 mmol/L) for 48 hours and stimulated with Ang II (0.1 micromol/L) for various times. GMC lysate was then immunoprecipitated and/or immunoblotted with SHP-1, SHP-2 and phosphospecific JAK2 and STAT antibodies. The HG and Ang II induced growth and collagen IV synthesis studies were performed in GMC transfected with JAK2 antisense or JAK2 sense. GMC growth was monitored via [3H]-thymidine incorporation, and collagen IV synthesis via ELISA. RESULTS: We found that Ang II-induced JAK2, STAT1, STAT3, STAT5A/B and SHP-2 phosphorylations were enhanced by HG, whereas that of SHP-1 was reduced. Ang II-induced growth and collagen IV synthesis also were increased under HG conditions. Transfection of GMC with JAK2 antisense oligonucleotides blocked the Ang II-induced growth and collagen IV synthesis in both NG and HG conditions. CONCLUSION: These results provide evidence that activation of the JAK/STAT pathway by HG or/and Ang II may be of importance in the increased GMC cell growth and collagen IV synthesis that is seen in diabetic nephropathy.

Angiotensin II↗
PubMed2002

Caspase activation in retinas of diabetic and galactosemic mice and diabetic patients.

Apoptosis of retinal capillary cells begins early in diabetes and likely contributes to the capillary obliteration that is an important feature of diabetic retinopathy. Caspases are proteolytic enzymes that are closely involved in the induction and execution phases of apoptosis, but their role in the development of diabetic retinopathy has not been studied previously. Our study focused on the measurement of activities of multiple caspases in retinas of mice at different durations of diabetes. Several caspases (including caspases-1, -2, -6, -8, and -9) were activated as early as 2 months of diabetes. The caspases activity pattern changed with increasing duration of disease, suggesting a slowly developing caspases cascade. Activities of executioner caspases (e.g., cas-6 and -3) became elevated after longer duration of diabetes, and the induction of cas-3 activity was associated with the duration of diabetes at which capillary cells begin to show evidence of undergoing apoptosis. Retinas from patients with type 2 diabetes likewise showed a significant increase in activities of cas-1, -3, -4, and -6. For comparison, retinal caspases were also measured in experimental galactosemia, another model that develops a diabetic-like retinopathy. The pattern of caspases activation differed between diabetes and galactosemia, but cas-1 activity became elevated soon after elevation of blood hexose concentration in both. Caspases offer new therapeutic targets to test the role of apoptosis in the development of diabetic retinopathy.

Amino Acid Chloromethyl Ketones↗
PubMed2002

[Detection of DNA damage of human sperm using single cell electrophoresis].

OBJECTIVES: To detect the sperm DNA damage and to evaluate its significance in male reproductive using single cell gel electrophoresis (SCGE). METHODS: Four hundred and eighteen sperm samples were analysed using the computer assisted analysis system and SCGE. The sperms samples were divided into five grades according to the extent of the sperm nuclear DNA damage. RESULTS: 1. When the sperm density is less than 20 x 10(6)/ml, the occurence of grade II and III are increased significantly; 2. In the unmotile grade d sperm the occurence of grade I comet amounts was 5.39%, the occurence of grade II and III was remarkably increased. There was a evidently variance between the grade d and grade a + b sperm. CONCLUSIONS: SCGE can be used to detect the sperm DNA breakage and to evaluate the sperm quality and damage.

Adolescent↗
PubMedDate not supplied

Development of methods for determination of the residues of 15 pesticides in medicinal herbs Isatis indigotica Fort. by capillary gas chromatography with electron capture or flame photometric detection.

Two multiresidue methods were developed for the determination of 15 pesticides (organochlorines, organphosphorus compounds, pyrethroids, and fungicides) in medicinal herbs Isatis indigotica Fort. and its formulations. The analytical procedure is based on ultrasonic assisted extraction and liquid-liquid extraction (LLE). After solvents were added, the raw material or granule sample was sonicated in an ultrasonic water bath and then centrifuged, filtered, and cleaned up by LLE. The infusion sample was extracted with petroleum ether by LLE. The pesticide residues were determined by capillary gas chromatography with electron-capture or flame photometric detection. Recoveries with the method at concentrations between 0.4 microg/kg and 10 mg/kg ranged from 70.2 to 119.5% for raw material, 73.2 to 105.1% for granule formulation, and 72.8 to 113.3% for infusion formulation. The relative standard deviation values were <20% for all of the pesticides studied. The pesticide detection limits were within the ranges 0.3-0.5 microg/L for endosulfan, 3-7.5 microg/L for pyrethroids, 0.7-32.5 microg/L for organophosphorus pesticides, and 0.1-0.6 microg/L for the other pesticides. The proposed methods are simple and rapid and provide simultaneous determination of pesticide residues in Isatis indigotica Fort. with acceptable recoveries and repeatability and an adequate limit of determination.

Chromatography, Gas↗