Asymmetric dimethyl-arginine (ADMA) response to inflammation in acute infections.

BACKGROUND AND METHODS: The endogenous inhibitor of nitric oxide synthase (NOs) asymmetrical dimethyl-arginine (ADMA) has been implicated as a possible modulator of inducible NOs during acute inflammation. We examined the evolution in the plasma concentration of ADMA measured at the clinical outset of acute inflammation and after its resolution in a series of 17 patients with acute bacterial infections. RESULTS: During the acute phase of inflammation/infection, patients displayed very high levels of C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin and nitrotyrosine. Simultaneous plasma ADMA concentration was similar to that in healthy subjects while symmetric dimethyl-arginine (SDMA) levels were substantially increased and directly related with creatinine. When infection resolved, ADMA rose from 0.62 +/- 0.23 to 0.80 +/- 0.18 micromol/l (+29%, P = 0.01) while SDMA remained unmodified. ADMA changes were independent on concomitant risk factor changes and inversely related with baseline systolic and diastolic pressure. Changes in the ADMA/SDMA ratio were compatible with the hypothesis that inflammatory cytokines activate ADMA degradation. CONCLUSIONS: Resolution of acute inflammation is characterized by an increase in the plasma concentration of ADMA. The results imply that ADMA suppression may actually serve to stimulate NO synthesis or that in this situation plasma ADMA levels may not reflect the inhibitory potential of this methylarginine at the cellular level.     

腹腔镜治疗精索静脉曲张235例

目的探讨腹腔镜治疗精索静脉曲张的疗效. 方法回顾分析1993年9月～2003年7月235例经腹腔镜精索静脉高位结扎术的临床资料. 结果 235例手术均获成功,手术时间5～20 min,平均12 min.术后住院2～5 d,平均3 d.210例随访6～18个月,9例复发,复发率4.3%(9/210),不育11例术后6～12个月后其妻受孕. 结论腹腔镜精索静脉高位结扎术微创、美观、疗效好,对双侧精索静脉曲张、开放性手术后复发和有腹股沟区手术史者尤为适用.     

侧脑室注射链脲霉素引起大鼠脑Aβ1-40和Aβ1-42表达增加

目的:探讨大鼠侧脑室注射链脲霉素(Streptozotocin,STZ)阻断脑内胰岛素信号传导与Aβ表达的关系.方法:24只SD大鼠随机等分为手术组和对照组(n=12),手术组双侧侧脑室注入STZ 3 mg/kg,第3日重复此剂量,对照组只手术操作但不注射药物.21 d后,采用免疫组化方法观测各组大鼠大脑皮层和海马区的Aβ1-40和Aβ1-42阳性表达.结果:与对照组相比,手术组皮层、海马Aβ1-40和Aβ1-42阳性细胞明显增多.结论:侧脑室注射STZ可以引起脑内Aβ表达增多,提示胰岛素/胰岛素受体系统障碍与阿尔茨海默病(AD)发病有密切关系.     

冠心病患者CRP水平与肾动脉狭窄的关系

【论文特点介绍】本研究观察了CRP是否可以作为肾动脉粥样硬化狭窄（ARAs）的独立危险因子。通过对危险因素进行多变量Logistic回归分析，结果表明年龄、冠脉病变严重程度、外周血管疾病是ARAS的独立危险因素，而CRP水平、高血压、高脂血症、肾功能不全并非ARAS的独立危险因素。     

Astroglial alterations in rat hippocampus during chronic lead exposure.

The present study was performed in order to follow the response of astroglial cells in the rat hippocampus to chronic low-level lead exposure. The experiments combined immunohistochemistry using anti-glial fibrillary acidic protein (GFAP) antibody and conventional transmission electron microscopy (EM). Chronic administration with drinking water [1 g% w/v (subclinical dose) of lead acetate dissolved in distilled water] was started through the mother's milk when pups were 7 days old. Following weaning, experimental offspring were treated for 3 months with the same concentration of adulterated water. The group of intoxicated animals and their controls were sacrificed by perfusion-fixation at 30, 60, and 90 days of exposure. After 60 days of lead treatment, staining of GFAP-positive cells demonstrated an astroglial transformation from the quiescent to the reactive state, characterized by an increase in GFAP. In control rats no changes in GFAP immunostaining were observed. The intensity of the astroglial response was enhanced after 90 days of lead intoxication, showing an increment of GFAP immunoreactivity. Quantification of these changes was made by computerized image analysis, confirming that the sectional areas of the astroglia in lead-exposed animals were larger than those in controls. These results are consistent with the ultrastructural alterations. Simultaneously with the increment in gliofilaments, intranuclear inclusions were seen in some astrocytes. The mechanisms by which lead affects astrocytes are unknown. Probably the astroglial changes induced by lead intoxication produce microenvironmental modifications that may disturb the neuronal function.     

Comparative studies of chemotherapy of human tumor cells in vitro by tritiated thymidine uptake inhibition and soft agar clonogenic assay

A rapid nonsterile short-term assay has been investigated in which percent inhibition of incorporation of the DNA precursor (3H)-thymidine is measured following exposure of tumor cells to the test drugs. To evaluate the usefulness of the short-term assay in providing a rapid reliable assessment of chemotherapeutic response, the short-term assay was compared with the soft agar clonogenic assay. Sensitivity to five anticancer drugs was compared using three human tumor cell lines (epidermoid carcinoma of the oral cavity, pancreatic carcinoma, and bladder carcinoma). The short-term assay produced results that were similar to results of the clonogenic assay in two of the three tumors tested, for three drugs (cis-platin, doxorubicin, and BCNU), but did not detect responses to two antimetabolites (5-FU and MTX) in any tumor. Further studies of this short-term assay should focus on alkylating agents and other nonantimetabolites.     

高功率微波辐照对大鼠血睾屏障通透性的影响

目的 探讨高功率微波（HPM）辐照大鼠睾丸对血睾屏障的影响。方法 雄性SD大鼠35只，随机分为7组，每组5只。6组为辐照组，1组为对照组。于辐照后2、6、12、4．8、96h和8d活杀大鼠后取双侧睾丸组织各约1mm^3，镧-醛固定液固定后制备电镜标本，在透射电镜下进行观察。结果 对照组可见硝酸镧主要沉积在曲细精管基膜部和精原细胞周围，未越过紧密连接；辐照后2-6h电镜下所见与对照组大致相同；辐照后12-96h，从基底部到管腔面的各层生精细胞之间、支持细胞内都有大量的镧颗粒沉积；辐照后8d，仍可见细胞间隙增大，部分区域靠近精子表面的镧颗粒沉积甚至比前面时间点的更为严重。结论 高功率微波辐照能够改变细胞的通透性，破坏血睾屏障的保护作用。     

Plasma volume in fasted pregnant rats

The effect of a two day fast on maternal plasma volume and plasma protein concentration was explored in pregnant rats. Fasting between days 17 and 19 of gestation prevented the rise in plasma volume observed in ad libitum fed rats. Plasma protein concentration declined between day 17 and day 19 in both fasted and not fasted rats. Placental weight was not reduced by fasting during this stage of gestation. Fetal weight in the fasted group was 91% of the fetal weight of the ad libitum fed group. These results show that acute undernutrition, like longer term food or protein restriction, can prevent adequate plasma volume expansion and slow fetal growth.     

Nutritional-inflammation status and resistance to erythropoietin therapy in haemodialysis patients.

BACKGROUND: Chronic kidney disease patients who are resistant to erythropoietin (EPO) treatment may suffer from malnutrition and/or inflammation. METHODS: In a cross-sectional study of haemodialysis patients, we investigated the relationship between the natural logarithm of the weekly EPO dose normalized for post-dialysis body weight and outcome measures of nutrition and/or inflammation [BMI, albumin and C reactive protein (CRP)] by means of multiple linear regression analysis. On the basis of the decile distribution of weekly EPO doses, we also evaluated four groups of patients: untreated, hyper-responders, normo-responders and hypo-responders. RESULTS: Six hundred and seventy-seven adult haemodialysis patients were recruited from five Italian centres. BMI and albumin were lower in the hypo-responders than in the other groups (21.3+/-3.8 vs 24.4+/-4.7 kg/m(2), P<0.001; and 3.8+/-0.6 vs 4.1+/-0.4 g/dl, P<0.001), whereas the median CRP level was higher (1.9 vs 0.8 mg/dl, P = 0.004). The median weekly EPO dose ranged from 30 IU/kg/week in the hyper-responsive group to 263 IU/kg/week in the hypo-responsive group. Transferrin saturation linearly decreased from the hyper- to hypo-responsive group (37+/-15 to 25+/-10%, P = 0.003), without any differences in transferrin levels. Ferritin levels were lower in the hypo-responsive than in the other patients (median 318 vs 445 ng/ml, P = 0.01). At multiple linear regression analysis, haemoglobin, BMI, albumin, CRP and serum iron levels were independently associated with the natural logarithm of the weekly EPO dose (R(2) = 0.22). CONCLUSIONS: Our findings support a clear association between EPO responsiveness and nutritional and inflammation variables in haemodialysis patients; iron deficiency is still a major cause of hypo-responsiveness.