细胞学诊断鼻咽癌141例分析

对141例鼻咽癌涂片细胞学检查进行分析,阳性诊断率为93.6％,假阴性为6.4％。涂片中巨大裸核癌细胞的出现是定性诊断鼻咽癌以及分型的依据。强调准确地取材,正确掌握癌与非癌细胞的鉴别要点,仔细阅片,密切结合临床和其它检查手段,是减少漏诊的保证。     

Assessing the adequacy of the logistic regression model for matched case-control studies

We apply results for the detection of outliers in logistic regression to the analysis of matched pairs data and illustrate the techniques with data from a matched pairs study of the relationship between iron-binding proteins and mortality in the Solomon Islands. Although the study includes 90 matched pairs, the conclusions change substantially with deletion of one or two pairs. Thus, even with reasonably large data sets, single observations may have a great impact on the results of an analysis. The identification of influential observations should constitute part of the analysis of matched case-control data.     

PBL融入诊断学实践教学初探

目的探讨将PBL教学法有机融入诊断学实践教学中的教学效果。方法同等条件下对部分教学内容在试验组和对照组分别采用PBL教学法和传统教学法,对两组学生卷面考试成绩、技能成绩、病历书写及分析成绩进行比较,同时对PBL组进行问卷调查。结果两组的卷面考试、技能、病历成绩等相比无显著差异;问卷调查评价显示PBL教学法在提高学生学习兴趣、分析和解决问题的能力、以及培养学生思维能力、自主学习能力、表达能力和团队协作能力等方面较之传统教学方法均有明显优势,但在知识传授系统性上存在不足。结论将PBL教学法有机融入诊断学实践教学中能够发挥其优势,有助于提高教学质量。     

中医特色诊断方法及其临床应用

结合50余年的中医教育、科研和临床工作,论述了中医诊断学学术思想应与临床结合的观点。认为中医诊断方法的客观化、技术化是发展的趋势,应重视传统中医诊断方法的客观化研究及中医特色诊断方法的应用;舌诊、脉诊是辨证的重要依据,应重视学习与应用;提倡以“治未病”理念指导临床,主张病证结合,辨证宜从脏腑、寒热、虚实角度执简驭繁。     

MicroRNA-145 targets MUC13 and suppresses growth and invasion of pancreatic cancer

Pancreatic cancer has a poor prognosis due to late diagnosis and ineffective therapeutic multimodality. MUC13, a transmembrane mucin is highly involved in pancreatic cancer progression. Thus, understanding its regulatory molecular mechanisms may offer new avenue of therapy for prevention/treatment of pancreatic cancer. Herein, we report a novel microRNA (miR-145)-mediated mechanism regulating aberrant MUC13 expression in pancreatic cancer. We report that miR-145 expression inversely correlates with MUC13 expression in pancreatic cancer cells and human tumor tissues. miR-145 is predominantly present in normal pancreatic tissues and early Pancreatic Ductal Adenocarcinoma (PDAC) precursor lesions (PanIN I) and is progressively suppressed over the course of development from PanIN II/III to late stage poorly differentiated PDAC. We demonstrate that miR-145 targets 3′ untranslated region of MUC13 and thus downregulates MUC13 protein expression in cells. Interestingly, transfection of miR-145 inhibits cell proliferation, invasion and enhances gemcitabine sensitivity. It causes reduction of HER2, P-AKT, PAK1 and an increase in p53. Similar results were found when MUC13 was specifically inhibited by shRNA directed at MUC13. Additionally, intratumoral injections of miR-145 in xenograft mice inhibited tumor growth via suppression of MUC13 and its downstream target, HER2. These results suggest miR-145 as a novel regulator of MUC13 in pancreatic cancer.     

A one-step dipstick assay for the on-site detection of nucleic acid

Objectives

We have developed a one-step nucleic acid dipstick assay (NADA) for visually detecting polymerase chain reaction (PCR) products within 3 min. “One-step” means that there were no additional procedures between amplification and detection.

Methods

This method was achieved through the use of asymmetric PCR and specially designed probes with appropriate melting temperature values. We initially combined one-step NADA with asymmetric capillary convective PCR (ACCPCR), an easy and rapid nucleic acid amplification technique, to construct an on-site nucleic acid diagnostic platform.

Results

We developed a diagnostic assay for the hepatitis B virus based on the ACCPCR-NADA platform to verify its feasibility. It exhibited an analytical sensitivity of three copies per test and a broad detection spectrum including genotype A–I. It also showed 97.9% sensitivity and 100% specificity based on the results observed using 67 serum samples with the Roche COBAS AmpliPrep/COBAS TaqMan (COBAS) system as the standard for comparison.

Conclusion

The results provide evidence for the feasibility of using an ACCPCR-NADA platform in practical applications, especially in on-site test.     

Characterisation of new monoclonal antibodies reacting with prions from both human and animal brain tissues

Post-mortem diagnosis of transmissible spongiform encephalopathies (prion diseases) is primarily based on the detection of a protease resistant, misfolded disease associated isoform (PrP(Sc)) of the prion protein (PrP(C)) on neuronal cells. These methods depend on antibodies directed against PrP(C) and capable of reacting with PrP(Sc)in situ (immunohistochemistry on nervous tissue sections) or with the unfolded form of the protein (western and paraffin embedded tissue (PET) blotting). Here, high-affinity monoclonal antibodies (mAbs 1.5D7, 1.6F4) were produced against synthetic PrP peptides in wild-type mice and used for western blotting and immunohistochemistry to detect several types of human prion-disease associated PrP(Sc), including sporadic Creutzfeldt-Jakob Disease (CJD) (subtypes MM1 and VV2), familial CJD and Gerstmann-Str?ussler-Scheinker (GSS) disease PrP(Sc) as well as PrP(Sc) of bovine spongiform encephalopathy (bovine brain), scrapie (ovine brain) and experimental scrapie in hamster and in mice. The antibodies were also used for PET-blotting in which PrP(Sc) blotted from brain tissue sections onto a nitrocellulose membrane is visualized with antibodies after protease and denaturant treatment allowing the detection of protease resistant PrP forms (PrP(RES)) in situ. Monoclonal antibodies 1.5D7 and 1.6F4 were raised against the reported epitope (PrP153-165) of the commercial antibody 6H4. While 1.5D7 and 1.6F4 were completely inhibitable by PrP153-165, 6H4 was not, indicating that the specificity of 6H4 is not defined completely by PrP153-165. The two antibodies performed similarly to 6H4 in western blotting with human samples, but showed less reactivity and enhanced background staining with animal samples in this method. In immunohistochemistry 1.5D7 and 1.6F4 performed better than 6H4 suggesting that the binding affinity of 1.5D7 and 1.6F4 with native (aggregated) PrP(Sc)in situ was higher than that of 6H4. On the other hand in PET-blotting, 6H4 reached the same level of reactivity as 1.5D7 and 1.6F4. This shows that 6H4 needs denatured PrP(RES) to reach maximal reactivity, confirming earlier results. As an exception, human PrP(RES) still reacted relatively poorly with 6H4 in PET-blotting, while 1.5D7 and 1.6F4 reacted well with PrP(RES) from most human CJD types. Taken together this implies that the binding epitope of 1.5D7 and 1.6F4 is accessible in the aggregates of undenatured PrP(Sc) (IHC) while the binding site of 6H4 is at least partly inaccessible. In techniques incorporating a denaturing and/or disaggregating step 6H4 showed good binding indicating increased accessibility of the binding site. An exception to this is human samples in PET-blotting suggesting that huPrP(RES) might not be as easily unfolded by denaturation as BSE and scrapie PrP(RES). Also of interest was the ability of 1.5D7 and 1.6F4 to discriminate between two allelic variants of PrP CJD(Sc) (VV vs. MM) in immunohistochemistry as opposed to the normally used antibody 3F4.     

Functional C1-inhibitor diagnostics in hereditary angioedema: assay evaluation and recommendations

Hereditary angioedema (HAE) is an autosomal dominant disease characterized by recurrent episodes of potentially life-threatening angioedema. The most widespread underlying genetic deficiency is a heterozygous deficiency of the serine protease inhibitor C1 esterase inhibitor (C1-Inh). In addition to low C4 levels, the most important laboratory parameter for correct diagnosis of HAE or angioedema due to acquired C1-Inh deficiency is reduced C1-Inh function (fC1-Inh).No direct recommendations about the assays for fC1-Inh or sample handling conditions are available, although this would prove especially useful when a laboratory first starts to offer assays on fC1-Inh for HAE diagnosis. In the present study we evaluated the performance of fC1-Inh assays in the 15 different laboratories that are specialised in HAE diagnostics and assessed inter-laboratory variation with each laboratory using their own assays and standards. A double-blind survey was conducted using plasma/serum samples from healthy donors and HAE patients and the uniformity of HAE diagnosis was evaluated.It can be concluded that the diagnosis of fC1-Inh deficiency was made correctly in most cases in this survey. We can recommend the chromogenic assay for the determination of fC1-Inh, while the complex ELISA needs further investigation.     

Noninvasive brain stimulation in Alzheimer's disease: systematic review and perspectives for the future

Background

A number of studies have applied transcranial magnetic stimulation (TMS) to physiologically characterize Alzheimer's disease (AD) and to monitor effects of pharmacological agents, while others have begun to therapeutically use TMS and transcranial direct current stimulation (tDCS) to improve cognitive function in AD. These applications are still very early in development, but offer the opportunity of learning from them for future development.

Methods

We performed a systematic search of all studies using noninvasive stimulation in AD and reviewed all 29 identified articles. Twenty-four focused on measures of motor cortical reactivity and (local) plasticity and functional connectivity, with eight of these studies assessing also effects of pharmacological agents. Five studies focused on the enhancement of cognitive function in AD.

Results

Short-latency afferent inhibition (SAI) and resting motor threshold are significantly reduced in AD patients as compared to healthy elders. Results on other measures of cortical reactivity, e.g. intracortical inhibition (ICI), are more divergent. Acetylcholine-esterase inhibitors and dopaminergic drugs may increase SAI and ICI in AD. Motor cortical plasticity and connectivity are impaired in AD. TMS/tDCS can induce acute and short-duration beneficial effects on cognitive function, but the therapeutic clinical significance in AD is unclear. Safety of TMS/tDCS is supported by studies to date.

Conclusions

TMS/tDCS appears safe in AD, but longer-term risks have been insufficiently considered. TMS holds promise as a physiologic biomarker in AD to identify therapeutic targets and monitor pharmacologic effects. In addition, TMS/tDCS may have therapeutic utility in AD, though the evidence is still very preliminary and cautious interpretation is warranted.