Age-related Changes in Bovine α-crystallin and High-molecular-weight Protein

The high-molecular-weight (HMW) protein from the lens is composed mostly of α-crystallin in a highly aggregated state. Bovine HMW protein was carefully separated from α-crystallin by size-exclusion chromatography. α-Crystallin has chaperone-like ability whereby it stabilizes other proteins under conditions of stress (e.g. heat). Comparison of bovine HMW protein and α-crystallin shows that the HMW protein has a markedly reduced chaperone ability compared to α-crystallin. However, in contrast to the results of other workers, we observe no alteration with age in the ability of α-crystallin to act as a chaperone. Using electrospray ionisation mass spectrometry, changes in the phosphorylation of the α-crystallin subunits with age have been quantified. Phosphorylation of α-crystallin occurs early in life but does not alter in proportion after about three years of age. In addition, phosphorylation of the A subunit of α-crystallin has little effect on its chaperone ability. As is found in the artificially prepared HMW complex of α- and γ-crystallin, NMR spectroscopy shows that in the naturally occurring HMW protein, the short C-terminal extension of the α_Bsubunit has lost its flexibility whereas the α_Asubunit extension is still flexible. Post-translational modifications therefore seem to have little effect on the chaperone action of α-crystallin, but alterations in the quaternary structure of α-crystallin via incorporation into the HMW aggregate, lead to major changes in the chaperone ability of the protein. The results are consistent with the notion that one of the contributing factors to cataract formation in the lens is the depletion of α-crystallin with age as it is converted into the HMW protein.     

不同低浓度罗哌卡因低位硬膜外镇痛对运动神经阻滞的临床观察

目的 观察不同低浓度罗哌卡因（ropivacaine,Rop）低位硬膜外镇痛对运动神经的阻滞作用。探讨罗哌卡因低位硬膜外镇痛的最佳药物浓度。方法 随机选择我院67例下腹部择期手术患者，术后随机分为5个治疗组（A、B、C、D、E）和一个对照组（F），3h后硬膜外腔用药。前5组使用不同浓度罗哌卡因（A：0.1%;B:0.15%;C:0.2%;D:0.25%;E:0.3%），F组使用0.9%生理盐水。注药前后20分钟分别观察、记录以下项目：1.视觉模拟评分（Visual analogue scale,VAS）；2.阻滞区运动神经反射；3. 下肢指令运动。结果 不同低浓度罗哌卡因均有程度不同的术后镇痛作用。对运动神经的阻滞作用A、B、C三组与对照组无显著性差异（P＞0.05），而D、E两组有显著性差异（P＜0.05）。结论 选择浓度为0.2%的罗哌卡因低位硬膜外镇痛既可以有效地发挥术后镇痛作用，又最大程度地减少了对运动神经的阻滞作用，有利患者术后恢复。     

Muscle mass index in haemodialysis patients: a comparison of indices obtained by routine clinical examinations.

BACKGROUND: Measurement of muscle mass is useful for evaluating protein nutritional status. Various methods for estimating muscle mass in haemodialysis patients have recently been developed. METHODS: The validity of the estimate of creatinine production calculated with the creatinine kinetic model (CKM) was examined in 46 haemodialysis patients by comparing it with the actual creatinine production, this being determined from the sum of creatinine appearing in the dialysate and the estimated metabolic degradation. The correlation of various other muscle mass indices with creatinine production was also investigated in these patients. RESULTS: The estimate of creatinine production using CKM was significantly correlated with creatinine production calculated from the spent dialysate plus an estimate for the extra-renal creatinine degradation (r=0.90, P<0.001). A Bland-Altman analysis revealed that the mean prediction error for the estimate of creatinine production by CKM was +0.10 g/day and the limits of agreement were +0.34 to -0.14 g/day. The cross-sectional area of the thigh muscle measured by computed tomography (CT) was also significantly correlated with creatinine production (r=-0.86, P<0.01). In contrast, the correlations of 3-methylhistidine production measured in the spent dialysate, the mid-upper arm muscle circumference and the skeletal muscle mass estimated by an anthropometric prediction model with creatinine production were lower (r<0.82). CONCLUSION: Creatinine production calculated using CKM and CT measurement of thigh muscle area are valid methods for estimating muscle mass during routine clinical examinations of haemodialysis patients.     

腹部大血管病变的3D DCE-MRA诊断

目的 阐述3D动态增强磁共振血管造影（three-dimensional　dynamic contrast-enhanced magnetic resonance angiog-raphy,3D DCE-MRA）的原理及其在腹部大血管病变诊断中的价值。方法搜集32例腹部大血管3D DCE-MRA检查的影像资料,对其影像表现进行回顾性分析。结果（1）团注试验:对比剂通过肾动脉水平腹主动脉内的高峰时间为17-23s;（2）正常表现3例,清晰显示腹主动脉及其分支;（3）腹主动脉瘤7例,均显示主动脉受累段不规则增宽及实际的动脉腔;（4）腹主动脉夹层18例,均显示内膜片、真假两腔以及分支动脉起源的位置,显示破口12处、再破口16处;（5）动脉粥样硬化3例,均显示腹主动脉迂曲,管径粗细不均;（6）髂总静脉血栓形成1例,左髂总静脉未显影。结论3DDCE-MRA是一种非损伤性血管成像技术,对腹部大血管病变的诊断有重要意义。     

A clinical study of nasopharyngeal masses

Out of 36511 patients attending the ENT OHD of R. G,. Aur Medical Callege & Hospital. Kolkata, in one year 0.08% patients were found tuning naspharyngeal mass. 30 cases of nasopharyngeal mass were studied. The peak incidence of nasopharyngeal mass was in the age group between II to 20 years (40%). The incidence in males (73%) was more than females(27%). The maximum ineldence was found among students (74%). Commonest ntuopharyngeal nuns teas antrochoanal polyp (30%). Next commlon masses were adenoids (23%)Juvenile angwfibroma(20%) and nasophartngeal carcinoma (13%). Nasal obstruction was the main presenting symptom(83%) followed by epistaxis (40%).     

Lithium-induced changes in the body mass index

A total of 117 manic-depressives who had been on lithium for a mean duration of 4.7 years were examined before lithium therapy and subsequently at intervals. Information relating to pre-lithium height and weight and current weight were determined and used to calculate the body mass index (BMI) for each individual. Other relevant variables such as age, sex, cumulative lithium dose, duration of therapy, thyroid profile and serum lithium levels were recorded. The results indicated that, although there was a nonsignificant increase in BMI for the whole population, lithium and sex were not significant predictors of any increase in BMI. In nearly 27% of patients BMI actually slightly decreased during lithium therapy. The overall conclusions from this study are that, in the population studied, lithium may not have exerted any pharmacological effects to increase BMI.     

Systematic screening for diabetic retinopathy with a digital fundus camera following pupillary dilatation in a university diabetes department.

AIMS: Screening for diabetic retinopathy (DR) is highly inadequate in France because of insufficient infrastructure and increasing disease prevalence. We describe the results of the first systematic DR screening programme established in a university diabetes department. METHODS: In this cross-sectional study conducted over 1 year, consecutive adult patients underwent three-field retinal photography with the Topcon TRC NW6S digital fundus camera following pupillary dilatation with Tropicamide 1%. A questionnaire provided information on patients' systemic and ocular history. Glycated haemoglobin (HbA1c) was measured at the screening visit.Two ophthalmologists graded the retinal photographs in a masked fashion. RESULTS: Of 1157 patients attending the diabetes department, 1153 (99.7%)underwent photographic screening. Images were gradable in 96% patients.Diabetic retinopathy was detected in 522 (45%) patients and sight-threatening DR in 167 (14%). Of 704 (61%) patients previously believed to have no DR,254 (34%) screened positive. The presence of DR was associated with age,insulin use and non-Caucasian ethnicity in Type 2 patients, and with duration of diabetes and HbA1c in Type 1 and Type 2 patients. Associated ocular pathologies were diagnosed in 612 (53%) patients. CONCLUSIONS: Our photographic screening programme using pharmacological mydriasis provided a high screening coverage feasible in a hospital setting. We obtained information regarding prevalence and associated risk factors of DR inpatients attending a tertiary care centre. Screening was well accepted by patients and met with no protest from city ophthalmologists. It generated considerable interest among endocrinologists and feedback of results is expected to improve optimization of glycaemic control.     

Identification of differentially expressed proteins in human stage I lung adenocarcinoma and tumor-adjacent tissues with two-dimension gel electrophoresis profiling

Objective： The aim of this study was to establish reproducible two-dimensional electrophoretic assay used for profiling and identification of differentially expressed proteins in human stage I lung adenocarcinoma and paired normal tumor-adjacent tissue. Methods： The proteins from 12 human stage I lung adenocarcinoma tissues and normal tumor-adjacent tissues were separated using isoelectric focusing electrophoresis （the first dimension） and the subsequent homogeneous SDS-polyacrylamide gel electrophoresis （SDS-PAGE） （the second dimension）. The differentially expressed proteins were determined with PDQuest image analysis software, and identified using matrix-assisted laser desorption/ionization time of flight mass spectrometry （MALDI-TOF-MS） and database searching. Results： The well-reproducible 2-DE gel patterns of human stage I lung adenocarcinoma and normal tumor-adjacent tissues were profiled and 26 differentially expressed proteins uncovered. Nine of these 26 protein spots were cut out from the preparation gels and determined with MALDI-TOF-MS. Searching against the protein database, four candidate proteins were identified. They were 60S acidic ribosomal protein P2, Cathepsin B1, Apolipoprotein A-I precursor, and La 4.1 protein. Conclusion： In this study, high reproducible 2-DE gel protein images of human stage I lung adenocarcinoma and paired normal tumor-adjacent tissues were achieved successfully, and 4 differentially expressed proteins were revealed. These data will be helpful for screen of early biomarker and study of molecular mechanisms of human lung adenocarcinoma.