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Biomedical subjects

Q Shao

Publications and source records attributed to Q Shao.

At least 19 recordsLinked to original sources
PubMed2003

Statistical visualization for data exploration: a case study on Sydney Olympic Park.

Due to the powerful graphic interface in modern computers, visualization techniques have become more and more popular for data exploration. As a preliminary investigation, visualization is a greatly useful tool to lead to further statistical analysis and modelling. It is likely that historical environmental data from a range of different studies may contain useful information that should be assessed for determining management actions. However, these historical data are collected from many different studies, which have different space and/or time scales making the visualization process complicated. In this paper we present several ways of visualizing historical data based on a study at Sydney Olympic Park. The tools include spatial coverage and variation for different spatial resolutions, temporal coverage and time series plots for different time scales, multi-panel scatterplots for a small number of variables and "one-to-all" scatterplots for a large number of variables.

Computer Graphics↗
PubMed2001

Comparative analysis and application of fluorescent protein-tagged connexins.

In order to examine connexin transport, assembly, and turnover in living cells, we tagged green fluorescent protein or its color variants to several members of the connexin family of proteins. When green fluorescent protein was tagged to the carboxyl terminal end of connexin43 (Cx43-GFP), the resulting fusion protein was transported and assembled into functional gap junctions. However, when GFP was tagged to the amino terminal end of Cx43 (GFP-Cx43), this chimera was biosynthesized, transported to the plasma membrane, but failed to form gap junction channels that could transfer Lucifer yellow. Single cells that expressed Cx43-GFP were capable of transporting this fusion protein to the cell surface in the absence of cell-cell contact. Imaging of Cx43-yellow (Y)FP (Cx43-YFP) was quite efficient; however, the low quantum yield Cx43-BFP and the requirement for ultraviolet excitation made this chimera less suitable for time-lapse imaging. Cx43-cyan C(FP) (Cx43-CFP) was more suitable for imaging than Cx43-blue (B)FP and could be effectively separated from Cx43-YFP. The versatility of tagging GFP to the carboxyl terminal end of other members of the connexin family was established when Cx32-GFP and Cx26-YFP were found to assemble into gap junctions capable of transferring Lucifer yellow. Finally, we are examining the effectiveness of using a new red fluorescent protein (DsRed) fused to connexins in combination with Cx-GFP to simultaneously examine the kinetics, transport and turnover of two connexins. Together, our studies suggest that tagging fluorescent proteins to the carboxyl terminal end of connexins is an effective and valuable approach for studying the life cycle and dynamics of connexins in living cells.

Animals↗
PubMed2001

Aggregated DsRed-tagged Cx43 and over-expressed Cx43 are targeted to lysosomes in human breast cancer cells.

To investigate if either wild-type or aggregated Cx43 is abnormally targeted to lysosomes in human breast tumor cells, we examined the fate of DsRed-tagged Cx43 and over-expressed Cx43 in communication-deficient HBL-100 and MDA-MB-231 cells. DsRed-tagged Cx43 was assembled into gap junctions in control normal rat kidney cells that express endogenous Cx43 but not in Cx43-negative HBL-100 cells. However, when HBL-100 cells were engineered to coexpress wild-type Cx43 a population of DsRed-tagged Cx43 was rescued and assembled into gap junctions. Co-expression of wild-type Cx26 failed to rescue the assembly of DsRed-tagged Cx43 into gap junctions. Immunolocalization studies revealed that DsRed-tagged Cx43 was aggregated and partially localized to lysosomes. Interestingly, when human MDA-MB-231 breast tumor cells over-expressed wild-type Cx43, Cx43 protein primarily localized to lysosomes. Together, these studies provide evidence for Cx43 being targeted to lysosomes as a result of misfolding and aggregation, while in other cases, the delivery of wild-type Cx43 to lysosomes appears to be due to defects innate to the breast tumor cell type.

Animals↗
PubMed2001

[Study on anticancer activity of Syngnathus in vitro].

OBJECTIVE: To study the anticancer activity of Syngnathus in vitro. METHOD: Observing the influence of different extracts from Syngnathus on growth of different cancer cell strains by MTT method. RESULT: It has been found out that the fat-soluble nonsaponified extract from Temminck et Schlegel and the alcoholic extract from Syngnathus acus have cytotoxic activities. The nonsaponified extract from Temminck et Schlegel can inhibit the growth of cancer cell strains KB, Hela, PAA, K562, and Bcap37, and the alcoholic extract from Syngnathus acus can inhibit the growth of cancer cell strin KB, But Bloch shows no apparent anticancer activity. CONCLUSION: Syngnathus has promising prospects as an anticancer Chinese medicine.

Animals↗
PubMed2000

Regulation of fas ligand expression during activation-induced cell death in T cells by p38 mitogen-activated protein kinase and c-Jun NH2-terminal kinase.

Activation-induced cell death (AICD) is a mechanism of peripheral T cell tolerance that depends upon an interaction between Fas and Fas ligand (FasL). Although c-Jun NH2-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) may be involved in apoptosis in various cell types, the mode of regulation of FasL expression during AICD in T cells by these two MAPKs is incompletely understood. To investigate the regulatory roles of these two MAPKs, we analyzed the kinetics of TCR-induced p38 MAPK and JNK activity and their regulation of FasL expression and AICD. We report that both JNK and p38 MAPK regulate AICD in T cells. Our data suggest a novel model of T cell AICD in which p38 MAPK acts early to initiate FasL expression and the Fas-mediated activation of caspases. Subsequently, caspases stimulate JNK to further upregulate FasL expression. Thus, p38 MAPK and downstream JNK converge to regulate FasL expression at different times after T cell receptor stimulation to elicit maximum AICD.

Animals↗
PubMed2000

Immunolocalization of 5alpha-reductase isozymes in acne lesions and normal skin.

BACKGROUND: Dihydrotestosterone mediates androgen-dependent diseases, such as acne, hirsutism, and androgenetic alopecia. This hormone is produced from testosterone by the 5alpha-reductase enzyme. There are 2 isozymes of 5alpha-reductase (types 1 and 2) that differ in their localization within the body and even within the skin. Activity of the type 1 isozyme predominates in sebaceous glands, where it may be involved in regulation of sebum production. Since specific inhibition of 5alpha-reductase type 1 may represent a novel therapeutic approach to acne, it is important to define the localization of these isozymes in normal sebaceous follicles and acne lesions. OBSERVATIONS: Skin biopsy specimens were obtained from the backs of 11 subjects: 8 with acne and 3 without acne. Sections of normal follicles, open comedones, closed comedones, and inflammatory lesions were incubated with antibodies to types 1 and 2 5alpha-reductase. In all samples, the type 1 antibody localized specifically to sebaceous glands, and the type 2 antibody localized to the companion layer of the hair follicle (the innermost layer of the outer root sheath) and granular layer of the epidermis. Localization of the type 2 isozyme was also noted within the walls of open and closed comedones and in endothelial cells from sections of inflammatory lesions. CONCLUSIONS: The immunolocalization of 5alpha-reductase isozymes in normal sebaceous follicles and acne follicles is similar to the pattern described in terminal hair follicles and corresponds with the findings of biochemical studies that have demonstrated predominance of type 1 activity in sebaceous glands. The function of type 2 5alpha-reductase in comedones or endothelial cells in inflammatory lesions is unknown.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2000

[A preliminary study of PSA level in 646 healthy men in Beijing].

OBJECTIVE: To evaluate the levels of total PSA (tPSA), free PSA (fPSA) and fPSA/t PSA ratio in healthy men in Beijing and analyze the relationship between age and PSA indexes. METHODS: Serum tPSA and fPSA were measured by electrochemi luminescence immune assay (ECLIA) and fPSA/t PSA ratio was calculated in 646 healthy men of 20 approximately 90 years old. The relationship between age and PSA indexes was analyzed by simple linear regression. RESULTS: In 20 approximately 30 years old cases, t PSA was 0.9 ng/ml +/- 0.6 ng/ml, fPSA was 0.27 ng/ml +/- 0.19 ng/ml and fPSA/t PSA ratio was 0.36 +/- 0.20. In 31 approximately 40 years old group, tPSA was 0.8 ng/ml +/- 0.6 ng/ml, fPSA was 0.22 ng/ml +/- 0.15 ng/ml and fPSA/tPSA ratio was 0.34 +/- 0.25. In 41 approximately 50 years old group, tPSA was 0.8 ng/ml +/- 0.6 ng/ml, fPSA was 0.21 ng/ml +/- 0. 14 ng/ml and fPSA/tPSA ratio was 0.34 +/- 0.23. In 51 approximately 60 years old group, tPSA was 1.0 ng/ml +/- 0.6 ng/ml, fPSA was 0.25 ng/ml +/- 0.15 ng/ml and fPSA/tPSA ratio was 0.31 +/- 0.19. In 61 approximately 70 years old group, tPSA was 1.0 ng/ml +/- 0. 7 ng/ml, fPSA was 0.25 ng/ml +/- 0.18 ng/ml and fPSA/tPSA ratio was 0.27 +/- 0.18. In 71 approximately 80 years old group, tPSA was 1.1 ng/ml +/- 0.7 ng/ml, fPSA was 0.31 ng/ml +/- 0.23 ng/ml and fPSA/tPSA ratio was 0.29 +/- 0.14. In 81 approximately 90 years old group, tPSA was 1.3 ng/ml +/- 1.1 ng/ml, fPSA was 0.4 ng/ml +/- 0.4 ng/ml and fPSA/tPSA ratio was 0.36 +/- 0.17. By univariate analysis, no correlation was found between serum PSA indexes and ages. CONCLUSIONS: The reference ranges of all PSA indexes in Chinese men may be lower than in that western men. There is no correlation between serum PSA indexes and ages. The reference range of 0 to 4 ng/ml used in the West may not be applicable to Chinese patients.

Adult↗
PubMed2000

[Influence of free radical inducer on the level of oxidative stress in brain of rats with fluorosis].

OBJECTIVE: To study changes in content of lipid peroxide and composition of fatty acids in the brain of rats affiliated with chronic fluorosis after treatment with free radical inducer (ferric ion). METHODS: Thirty-six Wistar rats were divided into three groups, fed with similar fodder and varied concentrations of fluoride in drinking water, and were killed five months after treatment. Lipid peroxidation was induced by ferric ions. Malondialdehyde content in brain was analysed by high-performance liquid chromatography; oxygen consumption was determined with an oxygen electrode and fatty acid composition was measured by gas chromatography in brain tissues of the rats. RESULTS: In the brain tissues, content of malondialdehyde and oxygen consumption increased, composition of polyunsaturated fatty acids decreased and that of saturated fatty acids decreased after treatment with free radical inducer in the treated group, as compared with those in control group. CONCLUSION: Over uptake of fluoride for a long term could cause potential increase in the level of oxidative stress in the brain tissue.

Animals↗
PubMed1999

Serotonin receptor subtypes that depolarize guinea pig inferior mesenteric ganglion neurons.

Our previous studies indicated that serotonin (5-HT) depolarized a majority of guinea pig inferior mesenteric ganglion (IMG) neurons and may be another transmitter for the noncholinergic late slow excitatory postsynaptic potential (ls-EPSP) in the IMG. However, the subtypes of 5-HT receptor mediating these responses have not yet been identified. Using intracellular recording, we examined the effect of 5-HT receptor antagonists with specificity to various 5-HT receptor subtypes on the 5-HT-mediated depolarization and ls-EPSP in IMG neurons in vitro. Cyproheptadine, a 5-HT(1/2) receptor antagonist, reversibly inhibited the slow, but not the fast, depolarization and ls-EPSP in the 5-HT-sensitive neurons. Both mianserin and spiperone, 5-HT(2) and 5-HT(1A) receptor antagonists, did not significantly alter either the fast or slow depolarizing responses or the ls-EPSP. The 5-HT(3) receptor antagonist MDL 72222 (Bemesetron) completely inhibited the fast depolarization with little diminution of the slow depolarization and ls-EPSP. Superfusion of putative 5-HT(1P) receptor antagonist, BRL 24924 (Renzapride), reversibly attenuated both the depolarization and ls-EPSP. However, 5-HT-insensitive neurons with ls-EPSP were found to be insensitive to both cyproheptadine and BRL 24924. In most 5-HT-sensitive neurons, the 5-HT(3) receptor agonist, 2-methyl-5-HT, and the selective 5-HT(1P) agonist, MCPP or 5-OHIP, evoked a fast and a slow depolarization in 55.6 and 71.4% of the neurons, respectively, without a significant effect on the membrane potential in 85.7 and 100% of the 5-HT-insensitive neurons. In 5-HT-sensitive neurons, MDL 72222 reversibly abolished the fast depolarization induced by 2-methyl-5-HT; BRL 24924 significantly inhibited the slow depolarization induced by MCPP or 5-OHIP, but not by SP. Prolonged superfusion of 5-HT-sensitive neurons with MCPP abolished the evoked ls-EPSP without inhibition of action potential. These results suggest that the fast and slow depolarizations in these neurons are mediated by 5-HT(3) and 5-HT(1P) receptor subtypes, respectively. The latter may also mediate the ls-EPSP in 5-HT-sensitive neurons.

Animals↗
PubMed1999

[Study on standards for safe and health-protective zone in firework plant].

A retrospective investigation on technology and situation in the production of fireworks, the cause and hazard consequences of accidents in blossom firework enterprises was carried out. The risk factors and their origins, the potential effects on surrounding environments and residents, the manufacture processes producing special potential energy in these enterprises were summarized and assessed. In addition, the consequences of explosive fire accidents were assessed retrospectively by the principle of explosion mechanics and Hopkinson Scaling Law. The safe and health-protective zone of the blossom firework plant was suggested.

Industry↗
PubMed1999

Captopril treatment improves the sarcoplasmic reticular Ca(2+) transport in heart failure due to myocardial infarction.

Although captopril, an angiotensin-converting enzyme (ACE) inhibitor, has been shown to exert a beneficial effect on cardiac function in heart failure, its effect on the status of sarcoplasmic reticulum (SR) Ca(2+) transport in the failing heart has not been examined previously. In order to determine whether captopril has a protective action on cardiac function, as well as cardiac SR Ca(2+)-pump activity and gene expression, a rat model of heart failure due to myocardial infarction was employed in this study. Sham operated and infarcted rats were given captopril (2 g/l) in drinking water; this treatment was started at either 3 or 21 days and was carried out until 8 weeks after the surgery. The untreated animals with myocardial infarction showed increased heart weight and elevated left ventricular end diastolic pressure, reduced rates of pressure development and pressure fall, as well as depressed SR Ca(2+) uptake and Ca(2+)-stimulated ATPase activities in comparison with the sham control group. These hemodynamic and biochemical changes in the failing hearts were prevented by treatment of the infarcted animals with captopril. Likewise, the observed reductions in the SR Ca(2+) pump and phospholamban protein contents, as well as in the mRNA levels for SR Ca(2+) pump ATPase and phospholamban, in the failing heart were attenuated by captopril treatment. These results suggest that heart failure is associated with a defect in the SR Ca(2+) handling and a depression in the gene expression of SR proteins; the beneficial effect of captopril in heart failure may be due to its ability to prevent remodeling of the cardiac SR membrane.

Animals↗
PubMed1999

Thrombin receptor mediated signals induce expressions of interleukin 6 and granulocyte colony stimulating factor via NF-kappa B activation in synovial fibroblasts.

OBJECTIVE: To clarify the mechanism of thrombin receptor mediated signal transduction and the induction of cytokines by thrombin stimulation in rheumatoid synovial fibroblasts. METHODS: Cytokines were measured by enzyme linked immunosorbent assay (ELISA) in the supernatants of cultured rheumatoid synovial fibroblasts stimulated by thrombin. To assess the mechanism of thrombin receptor mediated signal transduction in the rheumatoid synovial fibroblasts, electrophoretic mobility gel shift assay (EMSA), immunoglobulin kappa-chloramphenicol acetyltransferase (CAT) assay, and immunostaining for NF-kappa B subunit molecule was performed. RESULTS: Thrombin stimulation activated the inducible transcription factor NF-kappa B, and then induced subsequent expressions of interleukin 6 (IL6) and granulocyte colony stimulating factor (G-CSF) in the cells. CONCLUSION: Thrombin receptor mediated signal transduction could induce the expressions of IL6 and G-CSF, and increase inflammatory events in the cavum articulare via NF-kappa B activation.

Arthritis, Rheumatoid↗
PubMed1999

Effects of rat fetuin on stimulation of bone resorption in the presence of parathyroid hormone.

Rat fetuin, which is the rat counterpart of human alpha 2-HS glycoprotein and bovine fetuin, is only detectable in calcified tissues such as bone matrices and dentin, and bone cells such as osteoblasts and osteocytes immunohistochemically. The effect of this protein on bone resorption was examined to study its physiological role in bone metabolism. Rat fetuin increased bone resorption in the presence of low concentrations of parathyroid hormone (PTH), but it had no activity on bone resorption without PTH. The increase in bone resorption by PTH and PTH plus rat fetuin was inhibited by the addition of chymostatin, an inhibitor for cathepsin L. Moreover, we found that when type I collagen from rat was preincubated with rat fetuin, the digestion of rat type I collagen by cathepsin L was increased. These findings suggest that rat fetuin present in bone matrix is important in bone resorption.

Animals↗
PubMed1999

[An introductory clinical trial of three-monthly injectable contraceptive-depot medroxyprogesterone acetate].

OBJECTIVE: To evaluate contraceptive efficacy, continuative rate of use, side effects and acceptability of depot medroxyprogesterone acetate (DMPA) injectable contraception preparation in Chinese women. METHOD: This was an open study. One thousand nine hundred and eighty-five women acquiring contraception received DMPA injection after obtaining informed consent and were followed-up every 3-month up to one year. RESULTS: The total experience accumulated was 1,731.7 women-year with DMPA for 1,985 users. The one year continuation rate was 77.4%. Three subjects became pregnant, the one year accumulative life table failure rate was 0.2%. The accumulative discontinuation rates at one year for other reasons were amenorrhoea (4.8%), bleeding related (13.4%), other medical reasons (2.6%), other personal reasons (2.1%) and lost to follow-up (1.6%). The main complaints were irregular bleeding, amenorrhoea and prolonged bleeding. Lactating women had significantly lower rate of complaint. CONCLUSION: DMPA is a highly effective long-acting contraceptive, it could have good acceptability, especially for lactating women, under the well consultation.

Adolescent↗
PubMed1999

[A randomized multicentre clinical trial on different doses of mifepristone alone and in combination with anordrin as emergency contraception].

OBJECTIVES: To investigate the effectiveness and side-effects of different doses of mifepristone alone or in combination with anordrin given orally within 96 hours after unprotected intercourse as an emergency contraceptive. METHODS: 2,400 cases of healthy women were recruited and allocated randomly in 4 groups: single dose of 25 mg mifepristone, 25 mg mifepristone plus 7.5 mg anordrin, 10 mg mifepristone plus 5 mg anordrin and 10 mg mifepristone alone. The efficacy rates of contraception were estimated according to Dixon method. RESULTS: The total expected number of pregnancy was 171.9 for 2,387 subjects enrolled in the study. The number of observed pregnancies related to method failure was 32 cases. The contraceptive effectiveness rates for the above 4 groups were 80.9%, 85.3%, 90.6% and 67.3%, respectively. For the group received 10 mg mifepristone plus 5 mg anordrin, pregnancy rate was 0.7% which was significantly lower than that in 10 mg mifepristone alone group (2.2%, P < 0.05). The incidences of withdrawal bleeding were 9.2%, 4.9%, 3.4% and 6.7% for the 4 group respectively. Two groups received mifepristone in combination with anordrin showed significant lower incidence of withdrawal bleeding than those in mifepristone alone groups. CONCLUSION: Single oral administration of 25 mg mifepristone alone, and the combination of 10 mg mifepristone plus 5 mg anordrin were safe and effective treatment regimen for emergency contraception with no serious adverse reaction and disturbance on menstrual pattern.

Adolescent↗
PubMed1999

[Serum levels of levonorgestrel during long-term use of Norplant].

OBJECTIVE: (1) Assessment of longest effective contraceptive duration of Norplant (containing levonorgestrel, LNG) by serum levonorgestrel levels. (2) To observe the possible relationships between the serum LNG levels of long-term use (5 years) and body weight. METHODS: To determine serum LNG levels in 230 women among 1,356 cases at various intervals between 1 and 11 years after implantation using RIA kits provided by WHO. RESULTS: The average serum levels of LNG in users of Norplant at the 1st, 3rd, 5th years were 1,273.5, 924.0 and 739.6 pmol/L respectively. From the 5th to 7th years average serum LNG levels showed almost a linear decline, and from the 7th through 10th year it did not show much changes. The average serum LNG level was (511.1 +/- 209) pmol/L. A significant negative correlation was found between serum LNG levels and body weight at the 5th years. CONCLUSION: One set of Norplant implants may provide effective contraception for 8-10 years in women with body weights less than 60 kg.

Adult↗
PubMed1999

[Long-term efficacy of transurethral electrovaporization of the prostate for symptomatic benign prostatic hyperplasia].

OBJECTIVE: To observe long-term efficacy of transurethral electrovaporization of the prostate for symptomatic benign prostatic hyperplasia. METHODS: Two types of electrode of transurethral electrovaporization of the prostate (TVP) were performed on 150 patients of symptomatic BPH (mean age 74.8 years). The patients were assessed at baseline for both efficacy and followup at 36 months. Efficacy parameters evaluated included operation time (minutes), I-PSS and quality of life score, digital rectal examination, transrectal ultrasound, urodynamics and postvoid residual urine. RESULTS: 36 months after operation, I-PSS was decreased from 24.8 to 5.4 and the quality of life score also was decreased from 4.9 to 2.1. The mean peak uroflow was increased from 9.8 to 18.5 ml/s and postvoid residual urine was decreased from 108 ml to 22 ml (P < 0.05). The mean operation time was 44.7 min. Urodynamic results of 139 cases (92.7%) showed no bladder outlet obstruction, the remaining 11 cases showed severe bladder outlet obstruction to mild obstruction after 36 months. Hematuria was the only complication of our procedure. CONCLUSIONS: Significant clinical improvement is maintained with minimal morbidity. The long-term efficacy and safety of TVP is satisfactory. TVP is a potential useful procedure for transurethral resection of the prostate.

Aged↗