The effect of fluid viscosity on the hemodynamic energy changes during operation of the pulsatile ventricular assist device

Blood viscosity during operation of ventricular assist device (VAD) can be changed by various conditions such as anemia. It is known generally that the blood viscosity can affect vascular resistance and lead to change of blood flow. In this study, the effect of fluid viscosity variation on hemodynamic energy was evaluated with a pulsatile blood pump in a mock system. Six solutions were used for experiments, which were composed of water and glycerin and had different viscosities of 2, 2.5, 3, 3.5, 4, and 4.5 cP. The hemodynamic energy at the outlet cannula was measured. Experimental results showed that mean pressure was increased in accordance with the viscosity increase. When the viscosity increased, the mean pressure was also increased. However, the flow was decreased according to the viscosity increase. Energy equivalent pressure value was increased according to the viscosity-induced pressure rise; however, surplus hemodynamic energy value did not show any apparent changing trend. The hemodynamic energy made by the pulsatile VAD was affected by the viscosity of the circulating fluid.     

根据炎症特征对非变应性鼻炎进行分型的初步研究

目的研究非变应性鼻炎(non-allergic rhinitis,NAR)患者鼻腔与下气道的炎症特征,探讨根据炎症特征对NAR进行分型的方法及意义。方法收集2010年6月～2011年6月就诊的NAR患者117例,同期选取162例作为健康对照组。经皮肤点刺实验、鼻部和肺部症状视觉模拟量化评分(VAS)、鼻灌洗检测、诱导痰检测、血常规、鼻激发试验、支气管激发试验等炎症相关指标检查,评价鼻腔及气道炎症特征。根据鼻部及气道炎症特征对NAR进行分型并分析其临床意义。结果与健康对照组相比,NAR患者鼻灌洗、诱导痰、血嗜酸性粒细胞EOS、鼻激发和支气管激发阳性率均显著增高(P均<0.01)。鼻灌洗与诱导痰嗜酸性粒细胞(EOS)增高存在明显相关性(r=0.531,P=0.000),鼻激发与支气管激发等级存在相关性(r=0.190,P=0.040)。117例NAR患者中,鼻EOS增高39例(33.3%),鼻激发反应性增高50例(42.7%),EOS及激发均无异常28例(23.9%)。依上述特征,将NAR分为非特异型(A组)、EOS增高型(B组)和高反应型(C组)3组。结论 NAR患者鼻部以EOS增高及高反应性为主要炎症特征的全身炎症疾病,与下气道各炎症相关指标的增高以及血EOS增高存在明显的一致性。根据鼻部炎症特征提出的NAR分型方法有充分的临床和实验室依据,为NAR的诊断提供了更为科学和临床实用的方法,为进一步研究不同类型NAR发病机理以及根据NAR类型制定不同的治疗方案提供了理论依据。     

Variation in the use of laparoscopic cholecystectomy for acute cholecystitis: a population-based study

HYPOTHESIS: There is wide variation in the use of laparoscopic cholecystectomy (LC) for acute cholecystitis among all public hospitals in Hong Kong. The objective of this study was to determine the factors responsible for the use of LC for acute cholecystitis in a stable population. DESIGN: A retrospective survey on 2353 patients with pathologically proven acute cholecystitis treated with cholecystectomy in Hong Kong from 1998 to 2002. SETTING: All public hospitals in Hong Kong. RESULTS: The rate of using LC for acute cholecystitis increased by 30.4% from 1998 to 2002. We observed a wide variation in the use of LC for acute cholecystitis ranging from 3.7% to 92.9% (P<.001). There was no correlation between the number of cholecystectomies performed and the percentage of LCs performed in each hospital (P = .39). Logistic regression analysis showed that the hospital, year of operation, and age of the patients were independent variables for LC. CONCLUSIONS: A wide variation in the use of LC for acute cholecystitis was observed among the public hospitals in Hong Kong. Young female patients from selected hospitals recently are more likely to be treated with LC.     

Multi-dysfunctional pathophysiology in ITP

Idiopathic thrombocytopenic purpura (ITP) is an organ-specific autoimmune disorder characterized by a low platelet count and mucocutaneous bleeding. The decrease of platelets is caused by increased autoantibodies against self-antigens, particularly IgG antibodies against GPIIb/IIIa. The production of these autoantibodies by B cells depends on a number of cellular mechanisms that form a network of modulation, with T cells playing a pivotal role in pathophysiology. Delineation of the dysfunction of cellular immunity has recently been attempted. This review will focus on these recent advances applicable to ITP and to highlight how these may translate into novel approaches to treatment in the future. Multi-dysfunction in these networks may include a failure of self-antigen recognition and tolerance, involvement of abnormal cell surface molecules, altered Th1/Th2 cytokine profiles, impaired megakaryocytopoiesis and impaired cell-mediated cytotoxicity. In ITP, multi-step dysfunctions in these networks may take place that finally lead to the occurrence of the disease. Therefore, unveiling these dysfunctions is vital in understanding the pathophysiology of ITP and will finally lead to the development of new therapies to fight the disease.     

Predictive validity of the HCR-20V3 in a sample of Australian forensic psychiatric patients

The Historical Clinical Risk Management-20 Version 3 is the latest iteration in the HCR-20 series, adopting novel changes such as the addition of Relevance ratings and non-requirement to include the Psychopathy Checklist–Revised. This study aimed to examine these changes and compare the predictive validity of the HCR-20^V3 to the HCR-20^V2. The sample comprised of 100 forensic psychiatric patients, retrospectively followed up for a maximum period of approximately 13 years post-discharge from the Thomas Embling Hospital. Recidivism data were sourced from official police records. Results indicated good to excellent inter-rater reliability. The HCR-20^V3 significantly predicted violent recidivism (area under the curve = .70 to .77), levels of accuracy that were not significantly different from the HCR-20^V2. HCR-20^V3 Relevance ratings failed to add incremental validity above Presence ratings; however, the PCL–R improved upon the HCR-20^V3’s validity. The study represented one of the first evaluations of the HCR-20^V3 in Australia.     

肝移植术后颅内出血的防治

目的 总结肝移植术后颅内出血临床特点，探讨其原因、预防和治疗措施。方法 对我院从2003年10月到2005年5月的肝移植病例进行同顾性分析。结果 为395例病人做了406次肝移植。7例颅内出血，发病率1．8％（7／395）。发生时间2周内5例，1例治愈；29天和40天各1例，均治愈，死亡率57．1％（4／7）。6例病人存在凝血功能障碍，3例高血压，3例术中出血大于15000mL。结论 颅内出血是肝移植术后近期的常见死亡原因之一。颅内出血原因是多因素的，应采用减少术中出血、纠正凝血功能障碍、控制血压、抗菌素治疗和开颅手术等综合防治措施。     

颞浅动脉及静脉作为头颈部游离瓣移植受区血管的可靠性探讨

目的 探讨颞浅动、静脉作为头颈部游离瓣移植受区血管的可靠性和应用价值.方法2001年5月至2008年6月采用颞部血管作为受区血管的头颈部游离瓣移植25例,分析游离瓣的受区血管、术中及术后的血管危象及游离瓣的成活情况.结果 25例患者中,23块游离瓣采用颞浅静脉作为受区静脉,2例采用颞深静脉作为受区静脉,全部游离瓣均采用颞浅动脉作为受区动脉.全部游离瓣术后均未出现血管危象,游离瓣均获成活.结论本组结果表明,颞浅动、静脉是头颈部游离瓣移植可靠的受区血管.