Inhibition of GABA-gated chloride channel function by arachidonic acid

The effects of arachidonic acid and its metabolites on gamma-aminobutyric acid (GABAA) receptor function were determined in rat cerebral cortical synaptoneurosomes. Incubation of synaptoneurosomes with phospholipase A2 decreased muscimol-induced 36Cl- uptake. Arachidonic acid, the major unsaturated fatty acid released by phospholipase A2, also inhibited muscimol-induced 36Cl uptake. Similar inhibition was obtained with other unsaturated fatty acids (docosahexaenoic, oleic) but not with saturated fatty acids (stearic, palmitic). The effect of arachidonic acid on muscimol responses was inhibited by bovine serum albumin (BSA), and BSA enhanced muscimol responses directly, indicating the generation of endogenous arachidonic acid in the synaptoneurosome preparation. The generation of endogenous arachidonic acid was also indicated by the ability of 2 inhibitors of arachidonic acid metabolism, indomethacin and nordihydroguaiaretic acid (NDGA), to inhibit muscimol-induced 36Cl uptake. We conclude that arachidonic acid probably has both direct and indirect actions on muscimol responses since both enzyme inhibitors inhibited muscimol responses but did not prevent the effect of exogenously added arachidonic acid. In additional experiments, arachidonic acid metabolites generated by cyclooxygenase, prostaglandins D2, E2 and F2 alpha, each decreased muscimol responses; prostaglandins F2 alpha was the most potent inhibitor. Since the unsaturated fatty acids and their metabolites are most susceptible to peroxidation, a generating system of superoxide radicals was tested on muscimol responses. A combination of xanthine and xanthine oxidase inhibited muscimol-induced 36Cl uptake in a concentration-dependent manner. We propose that the inhibition of GABAA neurotransmission by arachidonic acid and its metabolites can lead to increased neuronal excitability. This mechanism may play an important role in the development of neuronal damage following seizures or cerebral ischemia.     

Endocrine therapy with or without radical prostatectomy for T1b-T3N0M0 prostate cancer

BACKGROUND: We retrospectively compared the 5-year survival rates of T1b-T3N0M0 prostate cancer patients treated either by endocrine therapy plus radical prostatectomy or endocrine therapy alone. METHODS: Clinical T1b-T3N0M0 prostate cancer patients were enrolled at 104 institutions in Japan. They were assigned to study 1 (n = 176), if they were indicated to prostatectomy, if not indicated, they were assigned to study 2 (n = 151). The indication of prostatectomy was based on the clinical judgement of physicians and/or patients. Those assigned to study 1 underwent prostatectomy and adjuvant endocrine therapy with or without preoperative androgen deprivation. Those assigned to study 2 were treated with leuprorelin acetate with or without chlormadinone acetate. They were followed-up every 3 months until death or for 5 years and over. RESULTS: Those assigned to study 1 were younger (mean age 67.2 vs 75.7 years), less advanced in clinical stage, and had lower prostate specific antigen levels (mean 43.8 vs 103.6 ng/mL). Death for any reason was observed less frequently in study 1 (n = 29, 16%) than study 2 (n = 50, 33%), and the 5-year overall survival rate was higher in study 1 (87 vs. 68%). However, prostate cancer deaths were comparatively seldom (9% in study 1 and 7% in study 2), resulting in the identical 5-year cause specific survival rate in both study groups (91%). In both study groups the overall survival was almost equal to the natural survival of age-matched men. CONCLUSIONS: Endocrine therapy offers a reasonable survival rate in T1b-T3 prostate cancer patients within a 5-year follow-up. Observation will be extended to determine 10-year outcomes.     

CO2 laser in cancer surgery of the breast: a comparative clinical study

Review of the literature reveals little to no data regarding the use of the CO2 laser as a surgical modality in the local treatment of breast cancer. This study was undertaken to determine if the CO2 laser is a surgical improvement over the scalpel, influencing patient care during the surgical and postsurgical period. In the author's series, a total of 209 procedures were performed. Within this group, 105 cases were performed with CO2 laser and 104 cases performed with the scalpel. Biopsies were always performed as a separate procedure prior to definitive surgery. This study was not designed to compare cure rates, the medical follow-up period being 1 year. The results of this study demonstrate a significant improvement in patients' postoperative care, surgical technique, and hospital cost-effectiveness.     

Minilaparotomy for type II and III radical hysterectomy: technique, feasibility, and complications

The objective was to assess the feasibility, the operative and postoperative outcome, and complications in the use of minilaparotomy for type II and III radical hysterectomy (RH) and pelvic lymphadenectomy (PLN) in early-stage cervical/endometrial cancer. A pilot study on 91 consecutive patients submitted to type II and III RH and PLN for early-stage cervical/endometrial cancer was performed between March 2002 and May 2003 in the Division of Gynecologic Oncology (UCSC, Rome). Thirty-two of 91 cases (35.2%) were eligible for minilaparotomy. The mean operative time was 156.7 min, whereas the mean intraoperative estimate of blood loss was 303.7 ml. A mean number of 32.7 pelvic lymph nodes and 6.2 common iliac nodes were removed. Ileus and removal of bladder catheter were on mean postoperative day 2.4 and 3.4, respectively. The mean number of postoperative days spent in the hospital was 3.7. Intra- and postoperative parameters were compared to laparotomy controls and literature data on laparoscopy and Pfannenstiel incision, showing substantially comparable results. Minilaparotomy is acceptable for selected patients undergoing radical abdominal hysterectomy (RAH) and PLN and does not compromise the adequacy of the procedure. It can be considered as an alternative to the classic midline vertical incision or even to the Pfannenstiel incisions and laparoscopy.     

关节镜下改良张力带固定治疗髌骨骨折患者的康复护理

对38例新鲜髌骨骨折患者行关节镜直视下骨折复位,改良张力带固定,术前和术后给予及时有效的功能康复和护理指导,取得满意的效果。平均随访18.6个月,骨折平均愈合时间7.5周,所有病例愈合良好,无并发症出现。关节镜治疗髌骨骨折为髌骨骨折提供了一种新的治疗方法。应针对其解剖特点制订科学、有效的护理方法。     

猪喉软骨硫酸软骨素的制备和自由基清除活性

直接用木瓜蛋白酶水解软骨,三氯醋酸除蛋白质,乙醇沉淀干燥得硫酸软骨素粗多糖,经DEAE-Sepharose fast flow离子交换层析分离纯化,高效凝胶渗透色谱和琼脂糖凝胶电泳测定其相对分子质量和纯度,比较硫酸软骨素粗品和纯品的体外自由基清除活性。结果显示硫酸软骨素粗品和纯品提取率分别为31.56±0.46%和19.79±0.78%,后者相对相对分子质量为75 174,粗品的DPPH.和.OH清除活性最强,随着产品纯度的提高,活性降低,而对于O2-.清除活性结果则相反。     

保留乳头乳腺癌改良根治术

作结合28例乳腺癌保留乳头改良根治术的手术经验，介绍了该手术的适应证及手术方法。认为保留乳头的乳腺癌改良根治术在我国可作为Ⅰ、Ⅱ期乳腺癌手术治疗的选择术式。     

改良电针痉挛连续两次发作治疗重性抑郁症疗效分析

目的　探讨改良电针痉挛连续两次发作治疗重性抑郁症的疗效。方法　使用YA型电针痉挛治疗仪 ,对 64例重性抑郁症患者进行连续两次发作 (试验组 )和单次发作 (对照组 )治疗 ,采用HAMD抑郁量表评分。结果　试验组临床显效率为 82 3 % ,对照组为 60 0 % ,试验组的疗效显著性地优于对照组 (χ2 =3 94,P <0 0 5 )。HAMD抑郁量表评定 :两组治疗前后总分均值比较均有显著差异 (P <0 0 1) ,试验组和对照组治疗后总分均值有显著差异 (t=5 .10 8,P <0 0 1) ;两组 4次发作治疗后总分均值比较试验组显效快于对照组 ;试验组的绝望感、认知障碍、迟滞因子分均值减低比对照组更明显 (P <0 0 1)。结论　改良电针痉挛连续两次发作疗法见效快、疗效好 ,无明显副作用 ,是治疗重性抑郁症的一种新方法     

二乙基二硫代氨基甲酸钠对沙土鼠脑缺血再灌注损伤的影响

沙土鼠脑缺血60min后,脑组织氧自由基和MDA含量无明显升高,而Mn-SOD的活性下降。缺血60min再灌注5min时,氧自由基显著升高。再灌注30min时,MDA的生成显著增多,Mn-SOD和Cu,Zn-SOD活性显著降低。缺血前15 min,iv DTC对缺血再灌注脑组织中氧自由基和MDA升高有显著抑制作用,对Mn-SOD活性有显著保护作用,且呈剂量依赖关系。     

大气颗粒物健康效应生物学机制研究进展

大量流行病学研究发现，大气颗粒物的污染水平与心肺系统疾病的超额发病、死亡存在密切关联，但其毒理学机制尚未阐明。本文对近年来大气颗粒物毒理学研究进行综述，包括大气颗粒物对呼吸系统、心血管系统及神经系统的毒性作用，并对氧化应激损伤、细胞钙稳态失衡及激活关键转录因子等分子毒理学机制进行了初步的阐述。