Peritoneal dialysis patient survival: a comparison between a Swedish and a Korean centre.

BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated.     

葛根素对血管性痴呆患者认知功能和事件相关电位P300的影响

目的观察葛根素对血管性痴呆（VaD）患者认知功能和听觉事件相关电位P300的影响。方法将70例VaD患者随机分成两组各35例，葛根素治疗组和对照组。应用简易精神状态检查量表（MMSE）评定两组患者治疗前后认知功能状况，并进行治疗前后P300检查。同时记录药物不良反应。结果两组各35例进入结果分析。治疗前两组MMSE评分、P300的潜伏期及波幅差异无显著性（均P〉0．05）。治疗14d、30d时，两组MMSE评分显著提高（均P〈0．01），P300潜伏期均有缩短，波幅均有提高（葛根素组P〈0．01，对照组P〈0．05）；治疗后14d时认知功能改善葛根素组明显优于对照组（总有效率分别为91．4％，71．4％）（P〈0．05）。两组治疗期间无严重不良反应。结论葛根素能够改善VaD患者的认知功能，这可能与葛根素的扩血管、脑保护作用有关。     

腹腔镜D3淋巴清扫联合保留盆腔自主神经直肠癌根治术对男性性功能的影响

目的 对比分析腹腔镜和开腹联合保留自主神经的D3直肠癌根治术对男性性功能的影响.方法 采用前瞻性研究的方法,将我院2006年6月至2007年10月入选的男性直肠癌患者119例随机分别进行开腹(OS组59例)和腹腔镜(LS组60例)手术,两组病例均采用联合保留自主神经的D3直肠癌根治术.在术前和术后3、6和12个月,分别采用IIEF问卷对男性性功能进行评价,对比两组病例术后性功能情况.结果 术后3次随访结果显示,LS组性功能障碍总发生率分别为23.3%、18.3%和11.6%,OS组分别为32.2%、27.1%和16.9%;两组比较,差异无统计学意义(P>0.05).结论 腹腔镜D3淋巴清扫联合保留自主神经的直肠癌根治术能够达到与开腹手术相同的效果.     

一种识别蛋白质的保守氨基酸残基的新方法

保守氨基酸残基在生物进化过程中具有较强的稳定性,一般不会发生太大的变化;生物信息学认为：氨基酸序列决定蛋白质结构,蛋白质结构决定蛋白质功能。因此,作者基于氨基酸的生化特性、几何特性和动态特性描述了一个新颖的算法去发现蛋白酶家族中的保守氨基酸残基,而保守氨基酸残基将对蛋白质的结构和功能的研究具有重要的意义。     

Impact of unilateral interposition sural nerve graft on the recovery of sexual function after radical prostatectomy in Japanese men: A preliminary study

PURPOSE: To determine the effect of an interposition nerve graft on sexual function after radical prostatectomy. METHODS: This study includes 64 patients, without hormonal therapy, who underwent a radical prostatectomy and intraoperative electrophysiological confirmation of cavernous nerve preservation. Twelve patients underwent a unilateral interposition sural nerve graft (UNG) for the resected neurovascular bundle. Twenty-one and 31 patients underwent bilateral nerve-sparing (BNS) and unilateral nerve-sparing (UNS) surgery without a nerve graft, respectively. As the age of patients was significantly younger in the UNG group than in the other groups, age-matched analysis also was conducted. Sexual function, evaluated by a self-administered questionnaire using the University of California Los Angeles-Prostate Cancer Index, was compared statistically among the three groups. RESULTS: In the age-matched analysis, the postoperative sexual function (SXF) score of the UNG group showed an intermediate level of recovery between those of the BNS and UNS groups at 12 months and reached the same level as the score at 12 months of the BNS group at 18 months postoperatively. The difference in the SXF score between the UNG and UNS groups began to appear after 6 months postoperatively and increased steadily with time. However, the background factors, such as the baseline SXF score, the usage rate of phosphodiesterase 5 inhibitors, and the rate of comorbidities were different between the UNG and UNS groups. CONCLUSIONS: The difference of the SXF score between the UNG and UNS groups increased with time after 6 months postoperatively. However, it might be difficult at present to attribute a better recovery of the SXF score to the nerve graft because of the difference in the background factors between the groups.     

Further evidence of preserved memory function in Alzheimer's disease

Memory performance of elderly patients in the early stages of Alzheimer's disease (DAT) was compared with that of elderly control subjects. In explicit tests of recognition memory, which involve conscious recollection, the DAT patients were grossly impaired. In implicit tests of anagram solution and wordstem completion, which do not require conscious recollection, the DAT patients were not impaired. These findings further support the idea that a separate memory system, episodic memory, underlies conscious recollection, that it is this system which is most commonly damaged in amnesia, and that memory systems not involving conscious recollection may be spared in the early stages of Alzheimer's disease.     

Urinary cyclic AMP response to bovine parathyroid hormone during treatment with neuroleptics

The urinary cyclic AMP response to bovine parathyroid hormone and urinary concentrating ability (max Uosm) after des-amino-D -arginine vasopressin were studies in nine volunteers and seven patients receiving long-term neuroleptic treatment. Max Uosm was lower in the patient group (770 ± 70 mosmol/kg) compared with the controls (948 ± 152 mosmol/kg) but the trend to a lower cAMP response to bovine PTH was not statistically significant. These results suggest that, although adenylate cyclase inhibition may contribute, other mechanisms are also important in the genesis of reduced uring concentrating ability in patients treated with psychotropic drugs.     

茶色素对冠心病及高血压病病人血小板功能的影响

目的：探索茶色素对冠心病、高血压病病人血小板功能的影响。方法：冠心病病人３６例（男性２１例，女性１５例；年龄６４±ｓ４ａ）；高血压病病人３０例（男性１８例，女性１２例；年龄５８±８ａ）。采用茶色素２５０ｍｇ，ｐｏ，ｔｉｄ，３０ｄ为一个疗程。结果：治疗后ＴＸＢ２下降，６－ｋｅｔｏ－ＰＧＰ１α上升，ＴＸＢ２／６－ｋｅｔｏ－ＰＧＦ１α比值下降（Ｐ＜０．０１或Ｐ＜０．０５），ＧＭＰ－１４０下降（Ｐ＜０．０５），ＰａｇＴ，ＰａｄＴ下降（Ｐ＜０．０５）。结论：茶色素具有降低血小板表面活性作用，抑制血小板聚集和粘附，抗血栓形成，改善微循环，对冠心病和高血压病病人起到积极的防治作用。     

ITERATIVE DYNAMIC PROGRAMMING FOR MINIMUM ENERGY CONTROL PROBLEMS WITH TIME DELAY

This paper presents the use of iterative dynamic programming employing exact penalty functions for minimum energy control problems. We show that exact continuously non-differentiable penalty functions are superior to continuously differentiable penalty functions in terms of satisfying final state constraints. We also demonstrate that the choice of an appropriate penalty function factor depends on the relative size of the time delay with respect to the final time and on the expected value of the energy consumption. A quadratic approximation (QA) of the delayed variables is much better than a linear approximation (LA) of the same for relatively large time delays. The QA improves the rate of convergence and avoids the formation of ‘kinks‘. A more general way of selecting appropriate penalty function factors is given and the results obtained using four illustrative examples of varying complexity corroborate the efficacy of the method.     

Chemical shift differences between free and Fab-bound peptide correlate with a two-stage selection of peptide sequences from a random phage display library to delineate critical and non-critical residues for antibody recognition

Epitope libraries provide a method to identify peptide ligands for antibodies, receptors or other binding proteins. As such, they provide a powerful tool to rapidly identify lead ligands in the drug discovery process. In an attempt to correlate structural information with the results from peptide screening, we have used NMR spectroscopy of peptide/antibody complexes to demonstrate that core residues identified through a two-stage selection process undergo a larger structural change upon binding antibody than do positions in the peptide amenable to a variety of side chains. The model system used was the M2 monoclonal antibody/Flag? octapeptide epitope system. We have analyzed two peptides: Ac-Asp-Tyr-Lys-Leu-Gly-Asp-Asp-Leu-NH₂ (peptide l), which contains several non-core positions randomized, and Ac-Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Leu-NH₂ (peptide 2), which closely corresponds to the original Flag? sequence. Enrichment of the peptides with ¹⁵N facilitated the investigation by permitting spectral editing of the peptide resonances in the presence of antibody. For peptide 1 the absolute shifts for the free vs. Fab-bound peptide were found to be largest for the amide groups of Asp-1 and Asp-6, in agreement with classification of these residues as critical by the phage display library selection process. For peptide 2 the largest absolute shifts were observed for Asp-1 and Asp-4, with the other aspartic acid residues also showing significant but smaller changes. © Munksgaard 1995.