Pathophysiological aspects of brain edema

Summary Two mayor types of brain edema, related to two different pathomechanisms, can be recognized: 1)cytotoxic type-where the main feature is the swelling of cellular elements of brain parenchyma and 2)vasogenic type-where an increased vascular permeability leading to accumulation of edema fluid inthe extracellular spaces plays the principal role. In this type of edema, there is a close interrelationship between extravasation of serum proteins and retention of water in the brain tissue. In theischemic brain edema both cytotoxic and vasogenic mechanisms are involved. A biphasic opening of the blood-brain barrier, associated with vasogenic edema, is observed following release of major cerebral artery occlusion. The first opening of the barrier is related to a reactive hyperemia which follows promptly recirculation. The second opening, recognizable after a delay, is associated with a severe ischemic brain tissue injury.Dedicated to Prof. F. Seitelberger on the occasion of his seventieth birthday     

常见眼眶病变的MRI诊断与鉴别诊断

目的：探讨眼眶病变的MRI诊断与鉴别诊断价值。方法：对29例经临床病理确诊的眼眶病变的病例进行回顾性分析，重点观察该类疾病的MRI表现。结果：眼眶病变29例，包括肿瘤10例。炎症10例，血管性病变3例，眼肌病变6例。其在MRI表现各具有影像学特征，眼眶肿瘤多表现为位于眼眶内、外的局限性软组织肿块，MR T1WI呈等或稍低信号，T2WI呈高或等信号多见；炎性假瘤则表现为眶内局限性软组织肿块或弥漫性异常信号．MR T1WI呈低信号，T2WI呈高信号，常伴有眼肌肥大或眼环增厚，泪腺肿大等。结论：MRI检查能显示眼眶病变的影像学特征，对其诊断及鉴别诊断具有重要价值。     

头颈部肿瘤放疗对甲状腺功能的损伤

头颈部肿瘤放疗后会引起不同程度的甲状腺功能减退.引起甲状腺功能减退的机制包括射线对甲状腺及垂体细胞的直接损伤、对相关血管的损伤以及自身免疫反应等.影响头颈部肿瘤放疗后甲状腺功能的因素主要有:放疗剂量、放疗技术、是否联合手术化疗等.通过对这些影响因素的研究可为防治甲状腺功能减退提供依据,从而提高患者生活质量.     

识时度势保持特色力求发展--中西医合校的回顾与思考

新疆医科大学为全国第二家中西医合并院校.在新疆进行中西医合校,实属时势所使,事在必行.强弱相合,处于弱势的中医学院只有坚持相对独立,才能保证于合校后发扬中医药特色、办好中医药教育.中西医合校,给原本弱小的新疆高等中医药教育事业的发展带来了诸多可供凭借和利用的积极因素,同时也存在不少负面影响.新疆医科大学在实践中认清了中西医同校的优势与缺憾,采取扶持和爱护中医的策略,不断尝试规避冲突、化解矛盾、趋利祛弊、务期和谐,终喜事业有成,使高等中医药教育得以在新疆生存,并越过低谷,走上健康发展之路.     

急诊抗菌药物的使用调查与分析

目的考察了解急诊抗菌药物的使用情况。方法随机抽取2008年7—12月的急诊处方2700张，对其中抗菌药物的应用情况进行统计分析。结果急诊抗菌药物使用率49．1％，药物应用形式以单用为主（占66．3％）；给药途径以口服和静脉注射为主。不合理用药处方占抗菌药物处方的10．8％，分别在选药方案、给药方案、溶媒使用、联合应用等方面存在问题。结论我院急诊抗菌药物的应用基本合理，但仍存在一定问题，需进一步加强管理。     

Bone growth patterns in Chinese children and adolescents: a 6-year follow-up study provides evidence for sexual dimorphism and tracking

Summary We prospectively examined bone growth patterns in 894 children aged 6–17 years at the baseline visit, with a 6-year follow-up. Results show bone “tracking” over a six-year interval and sexual dimorphism of bone attained levels and timing of peak bone growth. Our findings underscore childhood and adolescence as critical periods for building bone and developing gender differences. Introduction Bone growth patterns were prospectively examined in 894 Chinese children (496 males), aged 6–17 yrs, from a population-based twin cohort. Whole-body bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were measured by DEXA at baseline and a 6-yr follow-up. Methods Graphic smoothing plots and generalized estimating equations were used to model bone attained levels, growth, and “tracking”. Results Attained levels of BMC and BA increased curvilinearly with age. Male attained levels were higher than females after age ∼15 yr, but BMD was lower between 13–17 yrs (Tanner stage I to IV). In both genders, peak BMC and BMD growth lagged ∼2 yrs behind peak BA growth, which lagged 2 yrs behind peak height growth. Peak bone growth occurred 1–3 yrs later in males. Over the 6-yr follow-up, all bone measurements “tracked”, but “shifting” across ranks also occurred, and baseline tertile ranking influenced bone growth. Females with early menarche had higher attained levels than females with late menarche at age 12–13 yrs. Conclusion Our findings confirm and expand previous studies on peak bone growth conducted in Caucasian cohorts, particularly sexually dimorphic and maturational effects. The significant “tracking” of bone measurements in this 6-yr follow-up study underscores the importance that osteoporosis prevention should begin in childhood and adolescence. Fengxiu Ouyang and Binyan Wang contributed equally to this article. Source(s) of support: This study is supported in part by grant R01 HD049059, R01 HL0864619 and R01 AR045651 from the National Institute of Health and by the Food Allergy Project.     

Estimated research and development costs of rotavirus vaccines

Diseases like rotavirus afflict both upper- and lower-income countries, but most serious illnesses and deaths occur among the latter. It is a vital public health issue that vaccines for these types of global diseases can recover research and development (R&D) costs from high-priced markets quickly so that manufacturers can offer affordable prices to lower-income nations. Cost recovery depends on how high R&D costs are, and this study attempts to replace high, unverified estimates with lower, more verifiable estimates for two new vaccines, RotaTeq (Merck) and Rotarix (GlaxoSmithKline or GSK), based on detailed searches of public information and follow-up interviews with senior informants. We also offer a new perspective on “cost of capital” as a claim for recovery from public bodies. Our estimates suggest that companies can recover all fixed costs quickly from affluent markets and thus can offer these vaccines to lower-income countries at prices they can afford. Better vaccines are a shared project between companies and public health agencies; greater transparency and consistency in reporting of R&D costs is needed so that fair prices can be established.     

Simultaneous versus sequential optimal design for pharmacokinetic-pharmacodynamic models with FO and FOCE considerations

We consider nested multiple response models which are used extensively in the area of pharmacometrics. Given the conditional nature of such models, differences in predicted responses are a consequence of different assumptions about how the models interact. As such, sequential versus simultaneous and First Order (FO) versus First Order Conditional Estimation (FOCE) techniques have been explored in the literature where it was found that the sequential and FO approaches can produce biased results. It is therefore of interest to determine any design consequences between the various methods and approximations. As optimal design for nonlinear mixed effects models is dependent upon initial parameter estimates and an approximation to the expected Fisher information matrix, it is necessary to incorporate any influence of nonlinearity (or parameter-effects curvature) into our exploration. Hence, sequential versus simultaneous design with FO and FOCE considerations are compared under low, typical and high degrees of nonlinearity. Additionally, predicted standard errors of parameters are also compared to empirical estimates formed via a simulation/estimation study in NONMEM. Initially, design theory for nested multiple response models is developed and approaches mentioned above are investigated by considering a pharmacokinetic–pharmacodynamic model found in the literature. We consider design for situations where all responses are continuous and extend this methodology to the case where a response may be a discrete random variable. In particular, for a binary response pharmacodynamic model, it is conjectured that such responses will offer little information about all parameters and hence a sequential optimization, in the form of product design optimality, may yield near optimal designs.