深低温停循环逆行脑灌注脑组织自由基变化的实验研究

研究深低温停循环（ＤＨＣＡ）与逆行脑灌注（ＲＣＰ）时脑组织自由基的变化。健康杂种犬１４只，随机等分为ＤＨＣＡ组和ＲＣＰ组，在停循环前（Ａ点）、ＤＨＣＡ／ＲＣＰ３０分（Ｂ点）、ＤＨＣＡ／ＲＣＰ６０分（Ｃ点）ＤＨＣＡ／ＲＣＰ９０分（Ｄ眯）和复温再灌注３０分（Ｅ点）取脑皮层ｌｇ，检测丙二醛（ＭＤＡ）和超氧化物歧化酶（ＳＯＤ）水平。结果见两组在Ａ点ＭＤＡ和ＳＯＤ无差别。在Ｂ、Ｃ、Ｄ、Ｅ点，ＤＨＣＡ组ＭＤＡ     

Effects of 5-Hydroxytraptamine on Aggregation,Release Reaction and Mobilization of Cytosolic Free Calcium Concentration in Rabbit Normal and Washed Single Platelets

In rabbit platelet rich plasma (PRP), 5-hydroxytraptamine (5-HT,0.03～3μmol/L) induced decrease in light transmission (DLT) dose-de pendently with centralization, as revealed by electron microscopy. However, 5-HT did not induced platelet aggregation and release reaction. 5-HT-induced DLT was inhibited by methysergide (0.3～30μmol/L), indomethacin (0.3～10μmol/L) and PGE_1 (0.01～0.3μmol/L) in a dose-dependent manner, but not EGTA(0.3～3mmol/L). Collagen(Coll), arachidonic acid (AA), adenosine diphosphate (ADP) and a stable thromboxane A2 analoge(STA_2) also induced DLT before aggregation by themselves, which was also inhibited by PGE_1, but not inhibited by EGTA except for Coll However,Coll-, AA-, STA_2-and ADP-induced DLT were reduced by pretreatment of PRP with 5-HT dose-depen-dently. The duration of DLT by Coll and AA were decreased from 151.4±5.93 sec and 15(?)38±0.60sec to 45.44±4.04 sec and 9.00±1.25 sec respectively ((?)±s(?) P<0.01), but not by ADP and STA_2, 3μmol/L of ADP-and 0.3μmol/L of STA_2-induced aggregation which was not accompanied with release reaction were enhanced by 5-HT pretreatment, but in those (Coil 5μg/ml, AA 100～200μmol/L and STA_2 1～3 μmol/L) with release reaction, the amount of adenosine triphosphate(ATP)were suppressed significantly (P<0.001) by 5-HT pretreatment without the effect on the magnitude of aggregation, The mobilization of cytosolic free calcium concentration ([Ca~(2+)]i) was observed after 5-HT treatment in single washed platelet, the results indicated that the basic level of [Ca~(2+)] i was 64.78±3.24nmol/L and this level was increased dose-dependently and significantly at 30 sec after administration of 5-HT and the time of peak value of [Ca~(2+)] i was at 90～100 sec.The similar time courses of suppression of ATP released during aggregation, in cases of Coll(5μg/ml), AA (200μmol/L) and STA_2(3μmol/L), by 5-HT were also found in the present experiment.     

兔眼后房型人工晶体置入后房水内丙二醛测定

应用ＴＢＡ荧光法检测了兔眼单纯晶体囊外摘除后和晶体囊外摘除并后房型人工晶体置入后房水内丙二醛含量，这二种手术后房水内丙二醛含量比正常眼显著增高（Ｐ＜０．００５，Ｐ＜０．００１）。结果提示前房内发生了脂质过氧化反应，这一发现有利于对眼内后房型人工晶体表面细胞反应及前膜形成进一步认识。     

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.     

兔心肌挫伤心功能障碍与心肌细胞内Ca2+和线粒体ATP酶的变化

目的：探讨心肌细胞内游离钙([Ca^2 ]i)和心肌ATP酶变化在心肌挫伤（MC）后心功能障碍发生机制中的意义。方法：随机选取兔36只，分为6组：正常对照、伤后2、4、8、12、24h，每组6只。经右颈总动脉插管至左心室测左室压力。采用BIM-II型生物撞击机致成MC模型。在上述时相点测定左室压力，并测定心肌细胞内[Ca^2 ]i和心肌匀浆组织及线粒体ATP酶活力。结果：心脏收缩/舒张功能受到损害，心肌细胞内[Ca^2 ]i升高，心肌匀浆组织及线粒体ATP酶下降，相关分析表明心功能障碍与心肌细胞内[Ca^2 ]i含量升高呈明显负相关，与ATP酶活性降低呈明显正相关。结论：MC后心脏功能下降，心肌细胞内[Ca^2 ]i含量升高和ATP酶活性下降可能是其原因之一。     

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.     

Carbon blacks as EPR sensors for localized measurements of tissue oxygenation.

New electron paramagnetic resonance (EPR) oximetry probes were identified in the class of carbon black materials. These compounds exhibit very high oxygen sensitivity and favorable EPR characteristics for biological applications. At low pO(2), the linewidth is particularly sensitive to changes in oxygen tension (sensitivity of 750 mG/mmHg). The application of the probes for oximetry was demonstrated in vivo: the pO(2) was measured in muscle in which the blood flow was temporarily restricted as well as in tumor-bearing mice during a carbogen breathing challenge. The responsiveness to pO(2) was stable in muscle for at least 3 months. No toxicity was observed using these materials in cellular experiments and in histological studies performed 2, 7, and 28 days after implantation. In view of their EPR characteristics (high sensitivity) as well as the well-characterized production procedure that make them available on a large scale, these probes can be considered as very promising tools for future developments in EPR oximetry.     

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.     

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。