我国登革2型病毒43株包膜E蛋白基因的特征

对我国1987年流行的登革2型病毒43株包膜E蛋白基因的核苷酸序列进行了分析。结果表明登革2型病毒43株包膜E蛋白基因核苷酸序列含1485个核苷酸，编码495个氨基酸，并就其核苷酸序列及其相应的氨基酸序列与其它的登革2型病毒株进行了比较，发现核苷酸序列与我国1985年分离的登革2型病毒04株，新几内亚C株（NGC），牙买加株1409（JAM）和马来西亚当地流行株M1（登革出血热）、血2（登革休克综合征）、M3（登革热）同源性分别是95.8%、94.6%、97.5%、925%、92.7%和939%，氨基酸序列的同源性分别是94.3%、94.3%、96.0%、93.7%、93.7%和91.5%，推断出的氨基酸序列显示出12个保守的半胱氨酸残基和两个潜在的糖基化位点，分别位于Asn-67和Asn-153位。     

应用长链RT-PCR法扩增我国登革2、4型病毒株全长cDNA

目的：采用长链RT-PCR技术扩增登革2型及4型病毒基因组全长cDNA，为构建登革病毒全长cDNA克隆、表达，深入阐明致病机理及探索新型疫苗奠定基础。方法：根据已测定的登革2、4型病毒全基因组序列，设计上下游引物。从感染登革病毒的乳鼠脑中提取病毒基因组RNA，采用长链RT-PCR技术进行扩增。为检验扩增产物的特异性，以PCR产物为模板扩增覆盖基因组的10个片段。将含有复杂二级结构的5′非编码区扩增片段，在377A型自动测序仪进行序列分析。结果：扩增出登革2、4型病毒基因组全长近11kb cDNA分子，非编码区测序结果表明扩增产物为登革2、4型病毒所特有。结论：利用长链RT-PCR首次成功扩增出登革病毒全长cDNA分子。     

A cross-sectional study of the knowledge and attitude of medical laboratory personnel regarding continuing professional development

Background:

Continuing professional development (CPD) in Medical Laboratory Scientists (MLS) is aimed at equipping laboratory professionals with the necessary skills to enhance practice. The laboratory scientists are usually the first contact between the patient and health care system in aspects of diagnosis and monitory of diseases. As such, it becomes imperative to assess the knowledge of laboratory personnel regarding CPD.

Materials and Methods:

Self-administered questionnaires were distributed to 200 laboratory personnel''s attending the maiden CPD workshop organized by the Association of MLS in Jos the Plateau state capital.

Results:

One hundred and thirty-five (82 males and 53 females) of the 200 administered questionnaires were returned. Only 32 of them (23.7%) attended CPD program in the last 1 year with 10 (7.5%) engaging in online CPD. Five (3.7%) of the respondents had the privilege to attend an international CPD. Majority (95.2%) of the respondents identified CPD as an essential component of professional career development. Lack of sponsorship was identified as a major setback in CPD efficiency by 93.8% of respondents. About 58 (46.4%) noted that poor attendance in CPD workshops was due to unavailability of policy guideline for CPD. One hundred and twenty (95.2%) of respondents had an aim of improving their skills after attending CPD workshops.

Conclusion:

The overall attitude of Nigerian MLS toward attending CPD workshop is poor; however, the knowledge regarding the importance of CPD is adequate. There exists a gap between sponsorship for CPD by various institutions and MLS.     

Attenuated dengue 2 viruses with deletions in capsid protein derived from an infectious full-length cDNA clone

A full-length cDNA clone (pD212) of dengue virus type 2 isolated in China (DEN2-43) was constructed. Based on this, we constructed several mutants with deletions in capsid protein C using fusion PCR. These deletions removed part or almost all of the internal stretch of hydrophobic amino acid residues that is probably involved in virion assembly. We thus obtained viable mutant viruses. The propagation capacity of the mutant viruses in cell culture was impaired in parallel with the increasing size of the deletion, and the infectivity of mutant C(Delta42-59), from which all of helix III of capsid protein C was removed, was completely abolished. More importantly, the mutant viruses were highly attenuated in suckling mice but induced high levels of antibodies in adult mice. This study indicates that the structural and functional flexibility of capsid protein C make it a candidate target for the attenuation of dengue virus, which could open a promising new avenue for the development of live attenuated dengue vaccines.     

Anterior segment parameters associated with extramuscular manifestations in polymyositis and dermatomyositis

AIM: To evaluate the efficacy and safety of high-dose ultrasound cyclo-plasty (UCP) for the treatment of refractory glaucoma in Chinese patients. METHODS: In this 6-month retrospective study, 37 eyes of 37 patients suffering from severe glaucoma with uncontrolled intraocular pressure (IOP) of ≥21 mm Hg underwent 8-s ultrasonic cyclocoagulation with ten active piezoelectric elements. A complete ophthalmic examination was performed before and at 1d, 1, 3, 6mo after UCP. Therapeutic success was defined as IOP reduction from baseline ≥20% and IOP > 5 mm Hg without adding new glaucoma medication compare to baseline at the 6-month follow-up visit. In addition to mean IOP at each follow-up visit, medications used and complications were also detected and compared to baseline. RESULTS: After UCP procedure, the mean IOP was significantly reduced (P<0.01) from the preoperative 44.1±11.9 mm Hg to postoperative 26.7±11.8 mm Hg at 3mo, and 30.4±14.5 mm Hg at 6mo. The overall mean IOP reductions achieved at 3 and 6mo were 39% and 31%. Sixty-one percent of patients responded well to UCP treatment with a mean IOP reduction of 48% at 3mo and 42% at 6mo. Ocular pain in most of patients were alleviated. No serious intraoperative or postoperative complications occurred. CONCLUSION: High-dose UCP treatment is an effective and safe procedure to reduce IOP in Chinese patients with severe glaucoma.     

Inclusion body myositis — a case based clinicopathological update

Inclusion body myositis is a slowly progressive myopathy affecting predominantly the middle-aged and older patient population. It is a major form of the idiopathic inflammatory myopathies which are chronic systemic autoimmune diseases characterized by symmetrical proximal muscle weakness. Unfortunately, there is no effective therapy yet; however, the early diagnosis is essential to provide treatment options which may significantly slow the progression of the disease. In our case-based clinicopathological study the importance of the close collaboration between the clinician and the neuropathologist is emphasised.     

Effect of folic or folinic acid supplementation on the toxicity and efficacy of methotrexate in rheumatoid arthritis: a forty-eight week, multicenter, randomized, double-blind, placebo-controlled study

OBJECTIVE: To study the effect of folates on discontinuation of methotrexate (MTX) as single-drug antirheumatic treatment due to toxicity, to determine which type of adverse events are reduced, to study the effects on the efficacy of MTX, and to compare folic with folinic acid supplementation in a 48-week, randomized, double-blind, placebo-controlled trial. METHODS: Patients with active RA (n = 434) were randomly assigned to receive MTX plus either placebo, folic acid (1 mg/day), or folinic acid (2.5 mg/week). The initial MTX dosage was 7.5 mg/week; dosage increases were allowed up to a maximum of 25 mg/week for insufficient responses. Folate dosages were doubled once the dosage of MTX reached 15 mg/week. The primary end point was MTX withdrawal because of adverse events. Secondary end points were the MTX dosage and parameters of efficacy and toxicity of MTX. RESULTS: Toxicity-related discontinuation of MTX occurred in 38% of the placebo group, 17% of the folic acid group, and 12% of the folinic acid group. These between-group differences were explained by a decreased incidence of elevated liver enzyme levels in the folate supplementation groups. No between-group differences were found in the frequency of other adverse events or in the duration of adverse events. Parameters of disease activity improved equally in all groups. Mean dosages of MTX at the end of the study were lower in the placebo group (14.5 mg/week) than in the folic and folinic acid groups (18.0 and 16.4 mg/week, respectively). CONCLUSION: Both folate supplementation regimens reduced the incidence of elevated liver enzyme levels during MTX therapy, and as a consequence, MTX was discontinued less frequently in these patients. Folates seem to have no effect on the incidence, severity, and duration of other adverse events, including gastrointestinal and mucosal side effects. Slightly higher dosages of MTX were prescribed to obtain similar improvement in disease activity in the folate supplementation groups.