Telepathology: a tool to aid in diagnosis and quality assurance in cervicovaginal cytology

Telepathology: a tool to aid in diagnosis and quality assurance in cenicovaginal cytology
The purpose of this study is to evaluate the use of a Teletransmission System with regard to quality of diagnosis and screening so as to establish its potential role in gynaecological cytology. Three aspects of its use in cytopathology have been considered: diagnosis, training, and quality control. The circumstances in which the system may be used for diagnosis, together with its advantages and disadvantages, are examined and discussed. In general, the costbenefit in diagnostic use related to the experience of both the expert and the peripheral pathologist. The system may also contribute to training and quality assessment, particularly if combined with other automated services, such as an image data bank.     

Evaluation of a modified microscopic direct diagnosis of dermatophytosis

Here we present a modified protocol for dematophyte diagnosis, utilizing a simple centrifugation step to significantly decrease false-negative results of the original KOH direct microscopy-based technique. Although culture constitutes the gold-standard diagnosis, the time spent for results is a limit. Fast and low-cost techniques are important for infection screening in underdeveloped countries.     

Towards a molecular diagnosis of invasive aspergillosis and disseminated candidosis

A lot of in-house polymerase chain reaction assays have been reported for diagnosis of invasive aspergillosis and disseminated candidosis. Encouraging results have been published to anticipate the diagnosis over the conventional microbiological methods. However, the absence of standardized methods has led to diverging results. As a consequence, these tests are not recognized as consensual diagnostic criteria, in contrast with some antigenemia detection kits. The major breakthrough for improving the results of these methods is the emergence of real-time technologies. This markedly improves the reliability of the PCR results by dramatically decreasing the risk of false positive results due to PCR products carryover. Moreover, using the quantitative results provided by this technique, this allows to rapidly compare the efficiency of primers, probes, and DNA extraction methods. Therefore, the hope is to identify the more specific and sensitive parameters to implement comparative studies. Automated DNA extraction should also be useful to achieve this goal. Whatever sophisticated technology is used, we still have to define the meaning of detecting nucleic acids in a given clinical sample. This seems simple in normally sterile anatomical sites but less obvious for example in respiratory specimens for invasive aspergillosis or in blood for candidosis in heavily colonized patients. Additional studies of the kinetics of fungal DNA are needed. The development of real-time technology should improve our knowledge in order to give the clinicians informative clues for making a decision.     

Evaluation of a protocol for molecular broad-range diagnosis of culture-negative bacterial infections in clinical routine diagnosis

Aim: Introduction of a protocol for broad‐range diagnosis of bacterial infections, which remain negative in culture. Methods and Results: The new TaqMan real‐time PCR assay amplifies part of the 16S rRNA gene. Species are identified by subsequent sequencing and phylogenetic blast analysis. The analytical sensitivity showed to be 50 fg DNA per PCR. The lowest detectable bacterial cell concentration in blood was 1000 CFU per 200 μl EDTA‐blood. The utility in clinical routine diagnosis was evaluated by testing 136 clinical specimens. Bacterial pathogens were detected in 33 samples (24·3%) either by culture or molecular diagnosis. In 10 culture negative cases, pathogens such as Mycoplasma timone/orale, Ureaplasma parvum/urealyticum, Treponema pallidum, different streptococci and staphylococci were identified by molecular diagnosis only. Conclusions: The introduced broad‐range real‐time PCR protocol showed to be useful in the clinical routine in cases where bacterial infection was highly anticipated but culture remained negative. However, the obtained data have to be always interpreted with caution and in conjunction with the clinical data, crossing‐point values and with the Blast result of both the sample and the controls. Significance and Impact of the Study: This work introduces a new and well‐evaluated broad‐range real‐time PCR protocol for diagnosis of bacterial infections.     

Circulating miRNA and cancer diagnosis

miRNAs are a class of small RNA molecules with regulatory function, and play an important role in tumor development and progression. It has been demonstrated that tumor-derived miRNAs exist in the circulating nucleic acids of cancer patients. This phenomenon implies that detection of the circulating miRNA may be an effective method for non-invasive diagnosis of cancer. In this review, we summarize the applications of the circulating miRNA as biomarkers in cancer diagnosis, as well as the latest research progress in this area.     

Incremental hospital charges associated with obesity as a secondary diagnosis in children

Objective: The objective was to evaluate the association of obesity as a comorbidity with hospital charges, by comparing charges for pediatric hospitalizations with vs. without obesity as a secondary diagnosis. Methods: Using the 2000 Healthcare Cost and Utilization Project (HCUP) Kids’ Inpatient Database (KID), a nationally representative sample of pediatric hospital discharges, we identified the most common non‐pregnancy‐related principal diagnoses for children 2 to 18 years of age: asthma, pneumonia, affective disorders, and appendicitis. For each we compared mean charges and mean length of stay for hospitalizations with vs. without obesity as a secondary diagnosis, adjusting for relevant socio‐demographics and hospital type. Results: Among children's discharges in 2000, 1.1% listed obesity as a secondary diagnosis. These had a disproportionate likelihood of being older, black, Medicaid beneficiaries, and hospitalized at a general hospital. Adjusted mean hospital charges were significantly higher for discharges with obesity as a secondary diagnosis vs. those without: appendicitis ($14,134 vs. $11,049; p < 0.01), asthma ($7766 vs. $6043; p < 0.05), pneumonia ($12,228 vs. $9688; p < 0.05), and affective disorders ($8292 vs. $7769; p < 0.01). Whereas obesity as a secondary diagnosis was associated with a pattern of increased adjusted mean length of stay, only asthma and affective disorders had statistically significant differences (0.6 days) (p < 0.01). Conclusion: This national analysis suggests obesity as a secondary diagnosis is associated with significantly higher charges for the most common reasons for pediatric hospitalizations. This presents a financial imperative for further research to evaluate factors that contribute to higher inpatient charges related to obesity as a comorbidity and underscores the need for obesity prevention initiatives.     

Prenatal diagnosis in a mentally retarded woman with mosaic ring chromosome 18

We present a pregnant woman with mental retardation and mosaic for ring 18 referred for prenatal diagnosis. Major clinical features included short stature with clinodactyly in feet, foot deformity and club feet, hypotonia, kyphosis, and absence of breast development, low set ears, high arched palate, dental decay and speech disorder. Prenatal diagnosis was carried. Using amniocentesis. The fetus had a normal karyotype described as 46,XX. The fetus was evaluated for clinical features after delivery; she was healthy with no abnormal clinical characterizations.     

Development of a chromosomal DNA probe for the laboratory diagnosis of aspergillosis

Chromosomal DNA was extracted from clinical isolates of Aspergillus fumigatus of human and animal origin using the protoplast lysate method. The probe was developed by the nick translation of the chromosomal DNA genome fraction with p³² as the radiolabel. Hybridization of the probe with endonuclease-cleaved DNA of the same species resulted in a pattern of recognition sites specific for the species. The latter was not seen in other species encountered in clinical specimens. Trials were carried out on sputum experimentally inoculated with the fungus where crude DNA was directly extracted, treated with the endonuclease and hybridized with the probe. The efficacy of the probe was as good with the crude as the purified DNA. The specificity of the probe was determined by testing it against single and mixed DNA populations extracted from different species of several fungal and bacterial genera isolated from and/or known to occur in clinical specimens of respiratory infection origin. The sensitivity of the probe was assessed by detecting a DNA concentration in the specimen equivalent to 3 C.F.U.This research project was supported by the Mayo Visiting Clinician Program, Mayo Medical Center, Rochester, MN 55905, USA.     

MicroRNA-206 has a bright application prospect in the diagnosis of cases with oral cancer

Previous studies have shown that microRNA-206 (miR-206) exhibits anti-tumour properties in various tumours. Nevertheless, diagnostic significance of miR-206 in oral cancer is still poorly known. Our research was carried out to explore the performance of miR-206 in the diagnosis of oral cancer. Quantitative real-time polymerase chain reaction (qRT-PCR) method was adopted to measure the level of miR-206 in serum specimens from oral cancer cases and control individuals. Chi-square test was performed to analyse the correlation between miR-206 level and clinicopathological parameters of the cases. Receiver operating characteristic (ROC) curve was constituted to assess diagnostic accuracy of miR-206 in oral cancer. Serum miR-206 level in oral cancer patients was significantly lower than that in control individuals (P < .001). miR-206 expression was obviously related to T classification (P = .033), TNM stage (P = .008) and lymph node metastasis (P = .028). The area under the curve (AUC) of the ROC curve was 0.846 (95% CI = 0.797-0.896, P < .001) with a specificity of 72.7% and a sensitivity of 81.2%. It revealed that miR-206 might be a non-invasive indicator in differentiating oral cancer cases from control individuals. Down-regulation of miR-206 is related to the development of oral cancer. Serum miR-206 might be an effective indicator for early detection of oral cancer.     

Microbiological and serological diagnosis of Lyme borreliosis

In Europe, Lyme borreliosis is caused by Borrelia burgdorferi sensu stricto, B. afzelii, B. garinii and the recently described species B. spielmanii. For the development of diagnostic tools, the heterogeneity of the causative agents must be considered. The serological diagnosis should follow the principle of a two-step procedure: a sensitive enzyme-linked immunosorbent analysis as the first step, followed by immunoblot (IgM and IgG) if reactive. The sensitivity and standardization of immunoblots have been enhanced by the use of recombinant antigens instead of whole cell lysates. Improved sensitivity has resulted from the use of recombinant proteins primarily expressed in vivo (e.g. VlsE) and the combination of homologous proteins from different strains (e.g. DbpA). At present, detection rates for serum antibodies are 20-50% in localized, 70-90% in disseminated early and nearly 100% in late disease. Detection of the borreliae by culture or PCR should be confined to specific indications. The best results are obtained from skin biopsies (50-70% with culture or PCR) and synovial tissue or fluid (50-70% with PCR). Cerebrospinal fluid is positive in only 10-30%. Methods that are not recommended for diagnostic purposes include antigen tests in body fluids, PCR of urine and lymphocyte transformation tests.     

Interferon characterization associates with asthma and is a potential biomarker of predictive diagnosis

Interferon (IFN) plays a role in immune and inflammation responses. However, the effect of IFN in asthma is still not fully clear. The present study was conducted to better understand the role of IFN signatures in asthma. Blood samples from case–control studies (study 1: 348 asthmas and 39 normal controls and validation study 2: 411 asthmas and 87 normal controls) were enrolled. The single-sample gene set enrichment analysis (ssGSEA) method was used to quantify the levels of 74 IFN signatures. Gene Ontology analysis and pathway function analysis were performed for functional analysis and a protein–protein interaction (PPI) network was constructed. The area under the curve (AUC) value was used to evaluate the diagnostic ability. In our work, IFN-γ response-DN, negative regulation of IFN-γ secretion, IFNG pathway, negative regulation of response to IFN-γ, and type 1 IFN biosynthetic process showed higher levels in asthma. Functional analysis demonstrated that pathway and biological process involved in IFN signaling pathway, regulation of type 1 IFN production and response to IFN-γ. Hub IFN-related genes were identified, and their combination as biomarker exhibited a good diagnostic capacity for asthma (AUC = 0.832). These findings offered more insight into the underlying mechanism of how IFN signatures affected asthma. The use of the easy-to-apply IFN-related genes might serve as a promising blood-based biomarker for early diagnosis of asthma.     

Development of a enterovirus diagnostic assay system for diagnosis of viral myocarditis in humans

The coxsackieviruses type B3 (CVB3) are members of the genus Enterovirus of the family Picornaviridae. They are the commonest cause of chronic myocarditis and dilated cardiomyopathy. However, there is still no effective method for diagnosing CVB3 infection in humans. Here, a fast and accurate system that uses a capsid‐protein‐specific peptide sequence to detect CVB3 in the sera of patients with viral myocarditis was established. The peptide sequence was selected from the whole CVB3 capsid protein sequence by computationally predicting fragments with high antigenicity and low hydrophobicity. Two of eight possible peptide sequences were selected and commercially synthesized. The synthesized peptides encoded either the VP2 or VP1 capsid protein and induced immunoglobulin G antibody expression in immunized rabbits. Anti‐VP2 and anti‐VP1 sera detected the viral proteins extracted from CVB3‐infected HeLa cells. The newly synthesized peptides successfully induced antibody production. These peptides, applied in an ELISA system, detected anti‐CVB3 antibodies in virus‐infected mouse serum. Moreover, an ELISA system based on the VP2 peptide detected CVB3 infection in patients with positively identified CVB3‐induced fulminant myocarditis. These results indicate that these new peptides specifically interact with anti‐CVB3 IgG antibodies in mouse and human sera. This ELISA system should be useful for the clinical diagnosis of enterovirus‐induced myocarditis.     

Laboratory aids in the diagnosis of invasive candidiasis

The laboratory diagnosis of candidiasis continues to be problematic; however, there have been several advances in the past decade which promise to enhance our ability to identify patients at high risk for infection and/or to document invasive candidiasis in critically ill and immunocompromised patients. The introduction of commercially available biphasic blood culture medium and subsequently the lysiscentrifugation procedure has markedly improved the ability of laboratories to detect fungemia. Although serologic methods have not been very successful in diagnosing candidiasis in immunocompromised patients, several antigen detection methods are now under investigation. In addition, detection of fungal metabolites such as D-arabinitol remains promising. Finally, application of the techniques of molecular biology for typing and detection of fungal pathogens has expanded our understanding of candidal infections and may offer the most sensitive and specific means of diagnosing invasive candidiasis.     

诺如病毒的致病机制及诊断

诺如病毒(Norovirus, NoV)是引起全人群急性胃肠炎暴发和流行的主要病原体,也是引起食源性疾病的最常见非细菌性病原体。由于缺少有效的小型动物及培养细胞研究模型,目前对NoV感染的致病机制尚不清楚。NoV实验室诊断技术发展成熟,尤其是近年来新技术的应用将进一步推动其诊断水平的提高,满足公共卫生和临床诊疗的新需求。     

乳腺癌早期筛查和诊断生物标志物研究进展

2020年全球乳腺癌(breast cancer,BC)新发病例达226万例,占全部肿瘤新发病例的11.7%,是全世界发病率最高的癌症。早期发现、早期诊断和早期治疗是降低乳腺癌死亡率及改善预后的关键。尽管乳房X光筛查被广泛用作乳腺癌筛查的工具,但其假阳性、辐射性和过度诊断仍是亟待解决的问题。因此,亟需开发易于获取且稳定可靠的生物标志物,用于乳腺癌无创筛查和诊断。近年来多项研究显示来自乳腺癌患者血液中的循环肿瘤细胞DNA(circulating tumor cell DNA,ctDNA)、癌胚抗原(carcinoembryonic antigen,CEA)、糖类抗原15-3(carbohydrate antigen 15-3,CA15-3)、细胞外囊泡(extracellular vesicles,EV)、循环miRNA和BRCA基因突变等生物标志物,以及来自人体尿液、呼出气体(volatile organic compounds,VOCs)和乳头吸出液(nipple aspirate fluid,NAF)中的磷脂、miRNA、苯乙酮和十六烷等多种生物标志物与乳腺癌早期筛查和诊断密切相关。本文综述了上述生物标志物在乳腺癌早期筛查和诊断中的应用。     

Social dimensions of preimplantation genetic diagnosis: a literature review

The study provides a systematic overview of research on the social implications of preimplantation genetic diagnosis (PGD). The analysis focuses on empirical studies that provide insights into its heterogeneous fields of application and the concrete experiences of its users. The literature review shows that three areas of concern and controversial topics are particularly relevant for a social-scientific evaluation of PGD. Firstly, we present attitudes towards and assessments of PGD based on an ongoing expansion and transformation of its fields of application. This process includes not only more and more disorders and disease risks but also applications that are not disease-related. Secondly, there is evidence of significant gender asymmetries and financial concerns regarding the use of and access to PGD. Thirdly, the empirical studies point to a shift in normative expectations towards the idea of “genetic reproductive responsibility” and possible discriminatory consequences for individuals and families with diseases and disabilities.     

胆管癌诊断的分子生物学标志研究进展

胆管癌(cholangiocarcinoma, CCA)是第二常见的原发性肝脏恶性肿瘤。由于该病症隐匿,早期诊断困难,大多数患者在晚期才被发现且患者预后较差,因此早期诊断成为胆管癌治疗的关键。分子生物学标志可以标记系统、器官、组织、细胞及亚细胞结构及其功能的改变。大量研究表明,某些分子生物学标记物的检测有助于CCA的早期诊断,故本文旨在总结与CCA诊断相关的分子生物学标记物及其研究进展。     

Bayes' theorem in paleopathological diagnosis

The utility of Bayes' theorem in paleopathological diagnoses is explored. Since this theorem has been used heavily by modern clinical medicine, its usefulness in that field is described first. Next, the mechanics of the theorem are discussed, along with methods for deriving the prior probabilities needed for its application. Following this, the sources of these prior probabilities and their accompanying problems in paleopathology are considered. Finally, an application using prehistoric rib lesions is presented to demonstrate the utility of this method to paleopathology.     

Latent class model diagnosis from a frequentist point of view

This is in response to Garrett and Zeger (2000, Biometrics 56, 1055-1067) who, within the Bayesian framework, developed mainly graphical methods for latent class model diagnosis. Possible problems with this approach, and with its application to both generated and empirical data, are pointed out. The impact of the proposed tools cannot be understood by their reader, as no comparisons are made to results obtainable using established methods for latent class model diagnosis; this applies especially to overall goodness-of-fit tests, for which alternatives (bootstrap, Rudas-Clogg-Lindsay index of fit) are mentioned. Further, in one case of generated data, the methods proposed by Garrett and Zeger seem to give problematic results as to identifiability; in the case of the empirical data on major depression, they lead to accepting a suboptimal three-class model. In the latter case, one can be rather sure that an identifiable, well-fitting latent class model could have been identified--if Garrett and Zeger had also considered restricted latent class models.