Entomological survey and report of a knockdown resistance mutation in the malaria vector Anopheles gambiae from the Republic of Guinea

The purpose of our entomological survey was to estimate mosquito biodiversity, infectivity rates and insecticide resistance levels in Anopheles species in four study sites in a mining area with high malaria transmission in southeastern Guinea. Anopheles gambiae s.l. (77%) was the most common Anopheles collected followed by An. funestus (20%). The specimens of the An. gambiae complex were predominantly An. gambiae S form (97.6%) with 1.4% of An. gambiae M form found in Kérouané only, and 1% of An. arabiensis which was present in all four study sites. Anopheles gambiae S form and An. funestus were found to be infected with Plasmodium falciparum, with infectivity rates of 4.1% and 4.4% and inoculation rates of 0.60 and 0.19 infected bite/person/night, respectively. In addition, a high level (79%) of the knockdown resistance (kdr) L1014F mutation was reported in the populations of An. gambiae S form. The high malaria transmission that occurs in the prospected area of Guinea requires a long-term vector control programme. However, such a control programme will have to consider the presence of the kdr gene at a surprisingly high level within the dominant vector, which could reduce the expected impact of vector control.     

A recycling framework for the construction of Bonferroni‐based multiple tests

In this paper we describe Bonferroni‐based multiple testing procedures (MTPs) as strategies to split and recycle test mass. Here, ‘test mass’ refers to (parts of) the nominal level α at which the family‐wise error rate is controlled. Briefly, test mass is split between different null hypotheses, and whenever a null hypothesis is rejected, the part of α allocated to it may be recycled to the testing of other hypotheses. These recycling MTPs are closed testing procedures based on raw p‐values associated with testing the individual null hypotheses, and the class of such MTPs includes, for example, serial and parallel gatekeeping, fallback and Holm procedures. Graphical displays and a concise algebraic notation are provided for such MTPs. This recycling approach has pedagogical advantages and may facilitate the tailoring of MTPs for different purposes. Copyright © 2009 John Wiley & Sons, Ltd.     

胸膜活检阳性率的主要相关因素

分析了92例胸膜活检资料,认为其阳性率与下述因素有关:疾病种类、病例选择、活检器械、取材方法及技术、重复检查、临床医师与病理医师的配合。     

Surgical treatment for carcinoma of the papilla of vater

Eighty of 89 patients who underwent radical resection (resectability 89.9%) for carcinoma of the papilla of Vater between 1976 and 1992 were retrospectively reviewed. Seventy-three patients underwent pancreaticoduodenectomy (PD) and 7 underwent pylorus-preserving pancreaticoduodenectomy (PPPD). The postoperative mortality rate was only 3.8% (3 patients). The 3- and 5-year survival rates were 63.6% and 57.4%, respectively. Important factors influencing long-term survival were Stage (clinical stage = Stage), microscopic lymph node metastasis (n), duodenal wall invasion (d), vascular invasion (v), and the epithelium of origin. Early carcinoma of the papilla of Vater is defined as tumor in which invasion is limited within the papilla of Vater; in particular, carcinomatous invasion is within the muscle of Oddi (d₀) with n₀. PD and/or PPPD with radical lymph node dissection should be performed for carcinoma of the papilla of Vater, as these procedures can be performed with low morbidity and mortality.     

Relationship of clonogenic capacity to plating efficiency and vital dye staining of human periodontal ligament cells: implications for tooth replantation

The survival rate of avulsed permanent teeth following replantation is affected primarily by the duration of the extra-alveolar period and the nature of the storage conditions. These factors are believed to strongly affect the viability of periodontal ligament (PL) cells but in vitro assays of cell viability based on vital dye assays are only weakly correlated with the tooth survival rate after replantation. The aim of the present study was to examine the relative dependence of cell membrane integrity, attachment and clonogenic capacity of human PL cells on the temperature and duration of the extra-alveolar period and the type of storage medium. Twenty-four premolar teeth were extracted for orthodontic reasons from 9 patients 11–18 years of age. Teeth were maintained at 4°C or 23°C for 15, 30, 60 or 120 min in either milk or dry conditions. Cell membrane integrity was determined by BCECF/AM dye inclusion. Plating efficiency was determined by measurement of cell attachment at 3 and 6 h. The clonogenic capacity of progenitor cells was estimated by limiting dilution and colony counts. For all assays teeth stored in milk at 4°C showed the highest percentages of BCECF positive, attached cells with clonogenic capacity. Increased storage time (15–120 min) was associated with a 50% relative reduction of BCECF staining and a 5-fold relative reduction of cell attachment regardless of storage conditions. However, the clonogenic capacity of progenitor cells decreased 25-fold over the same duration of storage. These data demonstrate that in vitro assays of clonogenic capacity are much more sensitive to extra-oral storage time and storage conditions than dye inclusion or cell attachment. We suggest that in comparison with in vitro measures of cell membrane integrity, the clonogenic capacity of PL cells is more closely linked to tooth survival rate, probably reflecting the capacity of PL progenitor cells to recolonize the root surface after replantation.     

Frequency and causes of shunt revisions in different cerebrospinal fluid shunt types

Summary Shunt complications and revisions are common in hydrocephalic patients treated with a ventriculo-atrial or a ventriculo-peritoneal shunt. The reported revision rate differs very much but the rate of revision is close to 50% in many papers. Data from 884 hydrocephalic patients treated with various shunt types in the period 1958–1989 were recorded retrospectively in order to evaluate the frequency of revision for various shunt types and secondly to analyse the specific reasons for the shunt revisions.The rate of shunt revision was 45%. The Pudenz shunt was revised more often (62%) than the remaining shunt types. The Hakim and the Orbis-Sigma shunts had fewer revisions (35% and 27%, respectively) than the other observed shunt types. A defect of or an obstruction in the ventricular catheters was a frequent cause of revision followed by a defect or an obstruction of the distal catheter, a displacement of the distal catheter and an acute infection. Because of the higher rate of revision for the Pudenz shunt the rate of the above mentioned specific complications is also higher in most of the subgroups for that specific shunt type. Driven by these experiences it is reasonable to seek to develop and introduce new shunt types in an attempt to reduce the complication rate.     

Controlled Release of Substituted Benzole and Naphthoic Acids Using Carbopol ® Gels: Measurement of Drug Concentration Profiles and Correlation to Release Rate Kinetics

Purpose. The objective of this study is to correlate drug release mechanism with measured drug concentration profiles in gel layers of Carbopol^® matrices containing mesalamine or benzoic acid. Methods. Release rate experiments with Carbopol^® matrices were performed using a rotating disk apparatus. Matrices were frozen and the gel layer in the matrices was sliced using a microtome in a cryostat. Drug concentration profiles were determined by direct measurement of the concentration of the drug in the gel slices. The pH of the slices was measured using microelectrodes, and water content was measured by Karl Fisher titration. Results. The concentration gradient in mesalamine matrices decreased over time and correlated with square root of time release rate kinetics. The concentration profiles of benzoic acid were unchanged over time and correlated with zero order release rate kinetics. Carbopol gel layers were highly hydrated (93–95% water). Gel layers in matrices with mesalamine had a more alkaline microenvironmental pH. This higher pH resulted in increased growth of the thickness of the gel layer and a reduction drug diffusivity in comparison to benzoic acid matrices. Conclusions. The release rate kinetics of mesalamine and benzoic acid correlated to the measured concentration profiles. The shape of the concentration profiles is determined by the rate of growth of the Carbopol^® gel layer and drug diffusivity.     

长效避孕皮下埋植剂体外缓释行为研究

本文对以加成型硅橡胶为基质的左旋18—甲基炔诺酮长效避孕埋植剂的体外释放行为及对可能影响其释放量的诸因素,进行了观察与研究,结果表明:此长效避孕皮下埋植剂的体外释药行为,符合零级释药动力学规律。释药量受控释膜厚度,控释膜交联密度及释药面积的影响。体外释放药物曲线无明显爆破峰。     

已婚育龄妇女避孕措施变化趋势分析

目的:了解已婚育龄妇女避孕措施的变化趋势,为指导计划生育服务工作提供科学依据。方法:收集1983~2005年苏州市已婚育龄妇女避孕方法的资料,并用统计软件对其变化趋势进行了分析。结果:已婚育龄妇女节育率在88.38%~92.94%范围波动,长效避孕措施现用率从75.19%下降至71.27%,而短效避孕措施从12.86%上升至17.11%。宫内节育器的现用率从50.09%上升到66.50%;避孕套从1.94%上升到14.21%;其他避孕方法的现用率均呈下降趋势,其中女性绝育现用率从24.42%下降到4.50%。结论:节育率维持在较高水平;长效避孕措施现用率下降而短效避孕措施现用率上升;避孕方法使用趋于多样化,需要提供满足个性化需求的指导和服务。     

Heart rate variability and apnea during sleep in Down's syndrome

Autonomic system dysfunction has been reported to occur frequently in patients with Down's syndrome (DS) and is constituted mainly by an imbalance between the sympathetic and vagal systems. The analysis of heart rate variability (HRV) during sleep is a quantitative reliable method for studying such a mechanism, but it has not yet been extensively and adequately applied in DS. In this study, HRV during sleep was evaluated in seven DS patients and in six normal controls, by also controlling for the presence of sleep apnea or arousal. The main results were an increased sympathetic function (low-frequency component of HRV) and a decreased vagal activity (high-frequency component of HRV) in DS with respect to normal controls, during apnea-free periods. Moreover, the presence of apnea, in DS, induced a further significant increase in low-frequency and very low-frequency components of HRV during sleep Stage 2. This study provides additional evidence of a brainstem dysfunctioning in DS, responsible for the abnormal imbalance between the sympathetic and vagal systems and confirms the brainstem involvement already suggested in the literature in order to explain brainstem-auditory evoked potential abnormalities and central sleep apnea in these patients.