Comparison of Three Methods for Diagnosis of Cutaneous Leishmaniasis

Background

Leishmaniasis is one of the infectious parasitic diseases of highest incidence in the world. Cutaneous Leishmaniasis (CL) has long been reported in Shiraz, Southern Iran. There is a need to find a sensitive and specific method for treatment and control of the disease.

Methods

We have compared the sensitivity of the conventional methods microscopy and cultivation of lesion scrapes against PCR amplification of parasite kinetoplast DNA from these samples. The samples (n=219) were obtained from the patients clinically suspected of CL. The smears were stained with Giemsa for microscopy and cultured in Novy-Nicolle-McNeal (NNN) blood agar for promastigote growth. For PCR, the dry smears were scraped off the slides and DNA was extracted.

Results

The positive rates from 219 specimens were 76.71%, 50.68%, and 93.61% for microscopy, cultivation, and PCR, respectively. The highest correlation was found between PCR and microscopy method (P=0.014). In PCR assay, 95.61%, 3.9%, and 0.49% of the samples were identified as Leishmania major, L. tropica, and dermatropic L. infantum, respectively.

Conclusion

The PCR method appears to be the most sensitive for the diagnosis of CL and is valuable for identifying the other species of Leishmania with confusing dermatropic signs.     

Acute cytomegalovirus infection in liver transplant recipients: An independent risk for venous thromboembolism

Acute cytomegalovirus (CMV) infection is a commonly encountered complication in the post liver transplant setting. We present a case of a 71-year-old male with acute CMV infection, initially presenting with a gastrointestinal bleed due to acute CMV gastritis and later on complicated by acute venous thromboembolism occurring as an unprovoked event in the post liver transplant period. Traditional risk factors for venous thromboembolism have been well described in the medical literature. Sporadic cases of thromboembolism due to CMV infection in the immune compromised patients have been described, especially in the post kidney transplant patients. Liver transplant recipients are equally prone to CMV infection particularly in the first year after successful transplantation. Venous thromboembolism in this special population is particularly challenging due to the fact that these patients may have persistent thrombocytopenia and anticoagulation may be a challenge for the treating physician. Since liver transplantation is severely and universally limited by the availability of donor organs, we feel that this case report will provide valuable knowledge in the day to day management of these patients, whose clinical needs are complex and require a multidisciplinary approach in their care and management. Evidence and pathophysiology linking both the conditions is presented along with a brief discussion on the management, common scenarios encountered and potential impact in this special group of patients.     

Dental students' knowledge and compliance in cross infection control procedures at a UK dental hospital

OBJECTIVES: To assess the knowledge and clinical practice of dental students in infection control procedures at a UK dental hospital.
DESIGN: A questionnaire concerning various aspects of infection control was completed by all clinical dental students under examination conditions. Their actual clinical practice was later observed and certain aspects recorded.
SETTING: A UK dental hospital.
SUBJECTS: One hundred and eleven dental students from three clinical years completed the questionnaire. Clinical practice for all 3 years was observed in a total of 280 treatment events.
METHODS: The questionnaire was marked by two of the authors and observations recorded by another author. MAIN OUTCOME MEASURES: Degree of compliance with recognised policy for infection control.
RESULTS: Knowledge of infection control procedures was variable particularly concerning duties usually undertaken by the dental nurse. The suggested high compliance with masks and eye protection was not always apparent in clinical practice, although virtually all students washed their hands prior to donning gloves, which were worn by all students.
CONCLUSION: There can be marked differences between what students say they would do and what they actually do in clinical practice. The topic of infection control requires a pro-active approach throughout the course, since results for the final year were not significantly different from the other clinical yearS. Ways of improving compliance are discussed.     

Time dependent EC′, ECE and EC2E mechanisms at microdisc electrodes: simulations using adaptive finite element methods

In this paper we extend the work in [Electrochem. Commun. 5 (2003) 519] to more complex reaction mechanisms. We use the adaptive finite element algorithm described there to simulate the chronoamperometric current for EC^′ reaction mechanisms (catalytic reaction mechanisms) at inlaid and recessed microdisc electrodes and for ECE and EC₂E reaction mechanisms at microdisc electrodes.     

Anterior Cruciate Ligament Reconstruction with Bone Patellar Tendon Bone Graft through a Mini Arthrotomy

Instability after rupture of anterior cruciate ligament (ACL) may lead to recurrent episodes of giving way, an increased risk of meniscal injury and premature degenerative changes. A total of 25 cases with ACL injuries were evaluated after reconstruction with bone patellar tendon bone graft through a mini-arthrotomy. All patients were male. Maximum number of patients were between 25-30 years of age (40%). The most common modality of injury was contact sports (44%). Most common complaint was instability of knee (100%). Average Lysholm score increased from pre-operative of 47 (27-75) to post-operative of 87 (68-95). Two patients (8%) had retropatellar pain. Moderate to severe graft site tenderness was present in 4 (21%). After an average follow up of one year three months, the results were comparable with the results of arthroscopic reconstruction.Key Words: Anterior cruciate ligament reconstruction, Mini arthrotomy     

普罗布考和抗氧化维生素不影响体外实验条件下内皮细胞的白细胞粘附

为探讨预防动脉粥样硬化的药物普罗布考,维生素C和维生素E是否抑制内皮细胞表面粘附分子表达和白细胞一内皮细胞的粘附,以及这种抑制是否通过影响核因子－kB的活性来实现的,在液体流动小室中进行细胞粘附实验。用ELISA方法测定内皮细胞粘附分子E－选择素的表达;用电泳迁移率分析测定内皮细胞核因子－kB的活性,经肿瘤坏死因子α刺激的内皮细胞核因子－B活性增加,粘附分子E－选择素的表达上调（是基础水平的3．5倍）,其表面HL60细胞的粘附增加（是基础水平的4－26倍）,而抗氧化剂PDTC使所有这些变化都受到抑制。PDTC浓度为18umol/L时对粘附分子E－选择素的表达呈最大半抑制;PDTC浓度为52umol/L时对内皮细胞表面HL60细胞的粘附呈最大半抑制,普罗布考,维生素C和维生素E对肿瘤坏死因子α诱导的粘附分子表达和HL60细胞与内皮细胞的粘附没有作用,对核因子－kB的活性没有影响,临床上常用的这三种抗氧化剂并未影响作为动脉粥样硬化始动机制之一的E－选择素介导的白细胞－内皮细胞粘附水平。     

Shear‐induced unfolding activates von Willebrand factor A2 domain for proteolysis

Summary. Background: To avoid pathological platelet aggregation by von Willebrand factor (VWF), VWF multimers are regulated in size and reactivity for adhesion by ADAMTS13‐mediated proteolysis in a shear flow dependent manner. Objective and methods: We examined whether tensile stress in VWF under shear flow activates the VWF A2 domain for cleavage by ADAMTS13 using molecular dynamics simulations. We generated a full length mutant VWF featuring a homologous disulfide bond in A2 (N1493C and C1670S), in an attempt to lock A2 against unfolding. Results: We indeed observed stepwise unfolding of A2 and exposure of its deeply buried ADAMTS13 cleavage site. Interestingly, disulfide bonds in the adjacent and highly homologous VWF A1 and A3 domains obstruct their mechanical unfolding. We find this mutant A2 (N1493C and C1670S) to feature ADAMTS13‐resistant behavior in vitro. Conclusions: Our results yield molecular‐detail evidence for the force‐sensing function of VWF A2, by revealing how tension in VWF due to shear flow selectively exposes the A2 proteolysis site to ADAMTS13 for cleavage while keeping the folded remainder of A2 intact and functional. We find the unconventional ‘knotted’ Rossmann fold of A2 to be the key to this mechanical response, tailored for regulating VWF size and activity. Based on our model we discuss the pathomechanism of some natural mutations in the VWF A2 domain that significantly increase the cleavage by ADAMTS13 without shearing or chemical denaturation, and provide with the cleavage‐activated A2 conformation a structural basis for the design of inhibitors for VWF type 2 diseases.     

祛白酊质量标准的实验研究

目的：建立祛白酊的质量标准。方法：采用薄层色谱法鉴别其中的补骨脂素,异补骨脂素,栀子苷;导数分光光度法测定其中醋酸氢化可的松的含量。结果;薄层色谱鉴别方法有良好的重现性,专属性;醋酸氢化可的松在11－19ug.ml^-1呈良好的线性关系（r=0.9996)其含量测定平均回收率100．9％,RSD＝0．9％（n=5)。结论：制定的质量标准可以保证祛白酊的质量。