Effect of link protein concentration on articular cartilage proteoglycan aggregation

Previous work has shown that alterations in proteoglycan aggregates are among the first changes detected with aging, disuse, and degeneration of articular cartilage, yet the cause or causes of these alterations remain unknown. To determine if differences in link protein concentration can explain alterations in the assembly, size, and stability of articular cartilage proteoglycan aggregates, we isolated proteoglycan monomer (aggrecan) and link protein from adult bovine articular cartilage and then assembled proteoglycan aggregates from aggrecan and 0.8% hyaluronan relative to aggrecan weight, in the presence of 0, 2, 4, 6, 8, 10, 15, and 20% concentrations of link protein relative to aggrecan weight. We determined the amount, sedimentation coefficient, and stability of the aggregates by analytical ultracentrifugation and measured their dimensions by electron microscopy with use of the monolayer technique. Increased aggregate size, as determined by ultracentrifugation, was directly correlated with an increased number of aggrecans per aggregate and with increased hyaluronan length, as determined by electron microscopy. The concentration of link protein significantly influenced aggregation: concentrations of 6–8% produced maximum aggregation, aggregate stability, and uniformity of aggrecan spacing; concentrations greater than 10% led to the formation of superaggregates (aggregates with sedimentation velocities greater than 100 S that may result from linking two or more hyaluronan filaments) but decreased aggregate stability; and concentrations of less than 4% link protein significantly decreased aggregation, the size and stability of aggregates, and the regularity of aggrecan spacing. The latter observations suggest that a decline in the concentration of link protein could decrease the organization and stability of the articular cartilage matrix.     

安徽省农村居民哮喘病现况调查

本文通过对安徽省农村居民哮喘病的现况调查发现，哮喘病患病率为１．３３％，男性为１．４８％，女性为１．１９％；成人患病率为１．３４％，儿童为１．３２％。儿童哮喘患病率随年龄增长而下降，而成人哮喘病患病率随年龄增长而增加；儿童大部分婴幼儿起病，各年龄组中男性起病较女性晚，成人女性５０％起病２０岁前，而男性５０％起病３０岁前。农村哮喘以感染型为主，发病以冬季多见，发作主要诱因是感冒，哮喘病具有明显家族聚集性。     

颈椎骨折类型与脊髓损伤关系之临床观察

通过对９２例颈椎骨折病例的分析，发现屈曲型损伤最多见（５３％），其次为过伸型（２６％），压缩型（２１％）。屈曲型和压缩型多见于年轻人，而屈曲损伤导致的脱位及过伸型则多见于年龄较大者。爆裂骨折引起的神经损害最重，其次为屈曲型、过伸型及压缩（非爆裂）骨折。神经功能改善率以爆裂型骨折最差，死亡率亦最高，以压缩（非爆裂型）骨折最好，其次为过伸型及屈曲型。文内对各型的特点进行了详细讨论。     

人体β-胡萝卜素的肠转化和吸收后转化的研究

目的 :为了解部分中国人体内 β 胡萝卜素 ( β carotene ,以下简称 β C)转化维生素A (vitaminA ,以下简称VA)的效率 ,开展了本研究。方法 :使用稳定同位素稀释法对 15名 5 0 60岁健康农村志愿者 (男 9,女6)进行β C人体代谢实验。 2周适应期和 5 6天实验期内 ,志愿者接受常规膳食 ,避免大量VA和 β C摄入以及烟、酒和营养补充剂。实验第 1天 ,给受试者含 6mg氘标记 β C( 2 H8β C)玉米油胶丸 ,随半流质早餐 (脂肪热能比 2 5 % )一起摄入。实验第 4天 ,受试者以同样方法摄入含 3mg氘标记醋酸视黄醇 ( 2 H8RAC)油剂胶丸。实验第 1天和第 4天摄入标记物后 0 ,3 ,5 ,7,9,11,13h时 ,实验第 2 ,3 ,5 ,6,7,8,9,10 ,14,2 1,2 8,3 5 ,42 ,49,5 6天晨空腹时 ,采静脉血。用高效液相色谱仪 (HPLC)分离血清 β C和VA组分 ,再分别使用气相质谱仪(GC MS)和液相质谱仪 (LC MS)测定VA和 β C组分的同位素丰度。根据VA和 β C的浓度和同位素丰度 ,描述标记VA和β C在体内应答的血液动力学曲线。 结果 :所有 15名受试者对2 H8RAC应答明显 ;但是在对2 H8β C的应答方面 ,只有 11名受试者2 H4视黄醇应答曲线明显 ,有 4名受试者血清2 H4视黄醇应答曲线非常微弱。经过对备份血清样品进行的多次重复GC MS测定 ,我们目前初步?     

左心室造影功能成像的临床应用

为探讨左心室造影功能成像的价值与限度，我们选择冠脉及左心室造影者38例行左室功能成像，观察左室壁运动情况并与节段法室壁运动定量分析比较。结果示左室收缩正常18例，其各节段EF值平均39％，节段性收缩减弱7例，无收缩3例，矛盾收缩4例，普遍性收缩减弱6例，病变节段的EF值平均5～19％，明显低于正常者（P＜0．01）。结论：左室功能成像效果直观且客观，可作为室壁运动定量分析的一个重要补充。     

维拉帕米灌注治疗前列腺术后膀胱痉挛性疼痛的临床疗效观察

为探讨前列腺术后膀胱痉挛性疼痛的药物治疗效果，将２６例前列腺增生行耻骨上经膀胱前列腺摘除术后频繁发作膀胱逼尿肌无抑制性收缩导致膀胱痉挛性疼痛者，按随机抽样法分为两组，第１组１５例接受维拉帕米膀胱灌注治疗，第２组１１例作为对照，不用任何可能影响下尿中功能的药物。     

急性出血坏死性胰腺炎手术治疗的临床观察

总结了经手术证实为急性出血坏死性胰腺炎的５３例患者的手术疗效。发现该病应早期手术。若发病４天后手术，体温在３８℃以上、脉搏超过１２０次／分、收缩压在１２ｋＰａ（１ｋＰａ＝７．５ｍｍＨｇ）以下、有弥漫性腹膜炎、白细胞高于１６×１０９／Ｌ和术后有重要器官功能衰竭者，术后病死率明显增高。手术方法以胰腺坏死组织清除加三造瘘、腹腔三套管持续冲洗为优。抑制胰腺分泌的药物主要选用５氟脲嘧啶。引起胰腺感染的常见病原菌依次是大肠杆菌、肺炎克雷白杆菌、肠球菌、金黄色葡萄球菌、绿脓杆菌、奇异假单胞菌、链球菌、产气肠杆菌和脆弱类杆菌９种细菌。选用抗生素应遵守３个原则：①抗生素必须能通过血胰屏障。②能在胰腺组织中形成有效的治疗浓度。③能有效地抑制引起胰腺感染的病原菌。这样，才能取得良好的治疗效果。     

对居民使用液化气健康效应的初步探讨

对液化气燃烧后室内空气污染进行了流行病学调查，结果显示，液化气燃烧可造成ＳＯ＿２、ＮＯ＿２、空气总悬浮颗粒物和总烃类的室内空气污染。小鼠接触三个月出现Ｔ淋巴细胞计数降低、睡眠时间延长、骨髓嗜多染红细胞微核率增加、肺组织匀浆Ａｍｅｓ试验阳性率增高、雄性小鼠精子畸形率增加，并有明显的剂量－反应关系。对接触５年以上的人群调查发现，呼吸道、鼻和眼的自觉症状明显增加，咽炎、鼻炎、结膜炎患病率增高。人群尿液浓缩物Ａｍｅｓ试验和外周血红细胞微核率检出阳性结果，可能与液化气燃烧废气中含有致突变污染物有关。     

Biotransformation of caffeine, paraxanthine, theobromine and theophylline by cDNA-expressed human CYP1A2 and CYP2E1.

Six human cytochrome P450s expressed in HepG2 cells using vaccinia virus cDNA-directed expression, were used to study the biotransformation of caffeine and its metabolites. CYP1A2 alone was responsible for caffeine 3-demethylation and paraxanthine 7-demethylation; in addition, 1A2 catalysed virtually all reactions related to caffeine and its metabolites. The metabolic profile of caffeine biotransformation by CYP1A2 averaged 81.5% for paraxanthine, 10.8% for theobromine and 5.4% for theophylline formation. It remained quite uniform when caffeine concentrations were varied. The most striking finding was that CYP2E1 (the ethanol-inducible form) had major influences upon caffeine metabolism: in particular, it catalysed the formation of theophylline and theobromine from caffeine. Thus, the in vivo metabolite profiling of caffeine may reveal CYP2E1 activities in addition to the previously documented activities of CYP1A2, polymorphic N-acetyltransferase and xanthine oxidase.