天然有机化合物质谱研究——Ⅺ.苯丙型苷快原子轰击质谱MNa+的MIKES谱

研究了六种苯丙型苷与Na⁺加合离子的快原子轰击质谱(FAB—MS)和质量分离离子动能谱(MIKES)。结果表明:在FAB谱中[M+Na]⁺加合离子的丰度要比[M+H]⁺离子高得多。由此可给出糖苷的分子量信息,[M+Na]⁺离子的MIKES谱可给出糖基序列信息。     

Hyperlipidaemia in renal transplantation—risk factor for long-term graft outcome

Abstract. The role of hyperlipidaemia for the outcome of renal transplantation was evaluated in a prospective study involving 151 patients. Graft losses were associated with more pronounced pre-transplant lipid abnormalities. An increased risk of graft loss during the first two post-transplant years was found in patients with marked pre-transplant hypercholestero-laemia (≥6.9 mmol L^-1, P = 0.014; relative risk 2.2). Hypercholesterolaemia ≥6.9mmol L^-1 at 6 months after transplantation, present in 41/115 patients, was associated with a lower GFR ( P = 0.007) and more pronounced albuminuria ( P = 0.009) at 2 years. In patients with graft dysfunction (serum creatinine >160μmol L^-1) at 2 years, more pronounced lipid abnormalities before and at 6 months after transplantation were found. Between 6 months and 2 years, total and LDL cholesterol did not change significantly, but HDL cholesterol decreased ( P = 0.03). In conclusion, hyperlipidaemia is also a risk factor for the long-term outcome in renal transplantation. Further investigations are needed to determine whether graft losses and late graft failure can be prevented or ameliorated by treating hyperlipidaemia in renal transplantation.     

几种抗炎药对白三烯B4生物合成的影响

白三烯B₄为花生四烯酸5-脂氧酶代谢产物,是炎症反应中的重要介质。目前抑制白三烯B₄生物合成的药物尚不多见。本文建立了测定白细胞来源白三烯B₄的反相高效液相色谱法,并初步探讨了几种抗炎药对白三烯B₄生物合成的影响。结果表明阿斯匹林、消炎痛、炎痛喜康、氢化可的松及麝香第一色带对白三烯B₄生物合成几无影响,而氟灭酸可明显抑制白三烯B₄生成,提示它可能是5-脂氧酶抑制剂。     

GC/FTIR联用分析麝香风湿油

本文用气相色谱/富里叶变换红外光谱联用对中成药麝香风湿油作了分析研究,鉴定了其中的十个主要组分。并对其中三个组分用气相色谱内标法做了含量测定。平均回收率为100±1.0%,变异系数<2.0%。     

Identification and regulation of tissue plasminogen activator activity in rat cumulus-oocyte complexes

Plasminogen activators convert plasminogen into plasmin, a serine protease that initiates extracellular proteolysis. Two types of plasminogen activator activities have recently been demonstrated in granulosa cells, and the proteolysis-inducing enzymes are believed to be involved in ovulation. However, little attention has been paid to the presence of these enzymes in oocytes. Using sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by a fibrin overlay technique, we studied plasminogen activator activity in oocytes. Denuded oocytes collected from ovaries of hypophysectomized, estrogen-treated immature rats contained a tissue-type plasminogen activator (tPA), but not urokinase (uPA). In contrast, oocyte-free granulosa cells in these preantral follicles contained uPA, but not tPA. The tPA activity found in oocytes was plasminogen-dependent; incubation with increasing numbers (25-200) of denuded oocytes resulted in a dose-dependent increase in fibrinolysis only in the presence of plasminogen. Cellular localization of tPA was studied in the preantral follicles using an immuno-cytochemical method. Positive tPA staining was detected in the cytoplasm, but not in the germinal vesicle or zona pellucida of the oocytes. Furthermore, analysis using a reverse fibrin-overlay method did not reveal the presence of a plasminogen activator inhibitor. Culturing of denuded oocytes for 24 h increased the cellular content of tPA, but the enzyme activity was not further enhanced by treatment with FSH or forskolin. Also, no tPA activity was detected in the medium. We further studied plasminogen activator activities in the cumulus-oocyte complexes. Although only tPA activity was detected in freshly obtained cumulus-oocyte complexes, incubation for 24 h increased both tPA and uPA activity. Furthermore, tPA, but not uPA, activity was stimulated by treatment with FSH or forskolin. This was accompanied by the secretion of tPA into the medium. The identity of tPA and uPA in the cumulus-oocyte complexes was further confirmed by immunoprecipitation with specific antibodies. Isolation of denuded oocytes and cumulus cells after hormonal stimulation of the cumulus-oocyte complexes suggested that tPA activity was stimulated in both cell types and that the cumulus cells may mediate the action of FSH and forskolin on oocytes. In conclusion, the detection and regulation of tPA activity in cumulus-oocyte complexes suggest possible involvement of this enzyme in ovulation or the process of cumulus cell expansion and dispersion. Changes in oocyte tPA content may also serve as an indicator of oocyte development.     

Effect of BN 52021, a platelet activating factor antagonist, on dithranol-induced inflammation

The effect of BN 52021, a selective platelet activating factor (PAF) antagonist was studied on dithranol-induced irritant dermatitis. Pretreatment of the skin with 0.45% BN 52021 ointment significantly suppressed the decrease in capillary resistance, rise in skin temperature and increase in skin-fold thickness produced by dithranol.     

A Public Health Communication Intervention Using Edutainment and Communication Technology to Promote Safer Sex among Heterosexual Men Patronizing Entertainment Establishments

It is a challenge to reach out, develop and implement a communication intervention for heterosexual men (HSM) patronizing entertainment establishments (EEs) to promote safer sex. We described the theoretical basis and process from assessment to implementation where edutainment (talk shows) and communication technology (interactive web portal) was implemented. A female comedian hosted the talk shows. The portal contained an HIV risk profile calculator with individually tailored strategies to lower risk; two videos on real-life stories of unsafe sex and exit strategies to avoid casual or paid sex; as well as online support. We integrated edutainment, social cognitive theory (SCT) and the elaboration likelihood model (ELM). Edutainment techniques like humor through jokes, fun through games, and narrative persuasion through real-life accounts were applied. The SCT focused on modifying attitudes and social norm on sexual well-being, increasing self-perceived HIV/STI risk as well as building self-efficacy and skills in condom use. We applied the ELM to guide communication strategies and message development. For peripheral processing, we used cues like comedian delivery and charisma. For central processing, we focused on argument framing, issue involvement, argument quality, and modeling. The intervention was effective in promoting condom use with casual partners among the target group in Singapore.