ROLE OF REAL TIME PCR (RT-PCR) IN CLINICAL DIAGNOSIS FOR COVID-19 REVIEW

The pandemic of Coronavirus Disease 2019 (COVID19) has compelled scientists to create highly reliable diagnostic tools quickly in order to successfully and properly diagnose this pathology and thereby prevent infection transmission. Even though structural and molecular properties of the severe acute respiratory syndrome coronavirus 2 (SARSCoV2) were previously unknown, private research institutes and biomedical firms quickly developed numerous diagnostic procedures beneficial for making a correct detection of COVID19. Rapid antigen or antibody testing, immunoenzymatic serological tests, and RT-PCR based molecular assays are the most frequently used and validated procedures now available. The PCR has grown in popularity in molecular diagnostics to the point where it is still considered the gold standard for finding nucleotides from a variety of sources becoming an indispensable tool in the research lab. Because of its improved speed, sensitivity, reproducibility, and lower likelihood of carry-over contamination, real-time PCR has gained greater popularity. Currently, five different chemistries are employed to detect PCR product during real-time PCR. The self- fluorescing amplicons, DNA binding fluorophores, 5? endonuclease, neighbouring linear and hairpin oligoprobes, and self-fluorescing amplicons are all detailed in depth. We also go through the problems that have hampered the development of multiplex real-time PCR and the importance of real-time PCR in nucleic acid quantification.

Transmission risk of patients with COVID-19 meeting discharge criteria should be interpreted with caution / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

As of Apr. 22, 2020, the World Health Organization (2020) has reported over 2.4 million confirmed coronavirus disease 2019 (COVID-19) patients and 169 151 deaths. Recent articles have uncovered genomic characteristics and clinical features of COVID-19 (Chan et al., 2020; Chang et al., 2020; Guan et al., 2020; Zhu et al., 2020), while our understanding of COVID-19 is still limited. As suggested by guidelines promoted by the General Office of National Health Commission of the People's Republic of China (2020) (from Versions 1 to 6), discharged standards for COVID-19 were still dependent on viral real-time polymerase chain reaction (RT-PCR) tests of respiratory specimens, showing that recovered COVID-19 patients with twice negative RT-PCR could meet discharge criteria. Here, we examined two cases in which nucleic acid test results were inconsistent with clinical and radiological findings, leading to suboptimal care.

Chlamydia trachomatis in human immunodeficiency virus-infected men treated at a referral hospital for sexually transmitted diseases in the Amazonas, Brazil

OBJECTIVES: The aim of the present study was to determine the Chlamydia trachomatis prevalence and to identify the demographic, behavioural and clinical factors associated with C. trachomatis in human immunodeficiency virus infected men. STUDY: This was a cross-sectional study of C. trachomatis prevalence among human immunodeficiency virus-infected men enrolled at the Outpatient clinic of acquired immunodeficiency syndrome of the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado in Manaus, Amazonas, Brazil. C. trachomatis deoxyribonucleic acid from urethral samples was purified and submitted to real time polymerase chain reaction to identify the presence of C. trachomatis. RESULTS: A total of 276 human immunodeficiency virus-infected men were included in the study. The prevalence of C. trachomatis infection was 12% (95% confidence interval 8.1%-15.7%). The mean age of the participants was 34.63 (standard deviation 10.80) years. Of the 276 human immunodeficiency virus-infected men, 93 (56.2%) had more than one sexual partner in the past year and 105 (38.0%) reported having their first sexual intercourse under the age of 15 years. Men having sex with men and bisexuals amounted to 61.2% of the studied population. A total of 71.7% had received human immunodeficiency virus diagnosis in the last three years and 55.1% were using antiretroviral therapy. Factors associated with C. trachomatis infection in the logistic model were being single (p<0.034), men having sex with men (p<0.021), and having previous sexually transmitted diseases (p<0.001). CONCLUSION: The high prevalence of C. trachomatis infection among human immunodeficiency virus-infected men highlights that screening human immunodeficiency virus-infected men for C. trachomatis, especially among men having sex with men, is paramount to control the spread of C. trachomatis infection. .

A review of death occurred due to H1N1 infection in hospitals attached with SN Medical College, Jodhpur.

Background: H1N1 infection is a viral infection and it is communicable from an infected person to the susceptible contacts. A large number of H1N1 cases and deaths had been reported in districts of western Rajasthan during the pandemic of H1N1 influenza in the year 2009-10. In 2012-2013 also, Influenza ‘A’ H1N1 virus once again has reappeared in western Rajasthan. Aims & Objective: To review deaths due to H1N1 Positive patients in Hospitals attached with Medical College. Material and Methods: The present study was a hospital based study. The study was conducted by taking information from H1N1positive patients and their relatives from Umed, M.G., M.D.M., and Chest & T. B. Hospitals of Jodhpur from 1st January, 2012 to 20th March, 2013. During our study period, 1877 samples were collected from the suspected Outdoor and Indoor patients of hospitals. The collected samples were transported in VTM (viral Transport Media) to the testing Laboratories of Medical College/ Desert Medicine Research Centre (DMRC), Jodhpur and subjected to RT-PCR technique for the detection of H1N1 Influenza virus. Results: Out of 1877 samples collected during our study period, 375 samples were found positive. The study shows an H1N1 case positivity rate of 19.97%. During the study period, 68 patients died of H1 N1 infection with a Case fatality rate of 18.13%. Out of 68 H1N1 positive patients’ deaths, deaths were more (45; 66.16%) in female than in male (23; 33.82%). Out of 45 women who died of H1N1 infection, 33.82% (23) of the women were pregnant. The study also reveals a higher incidence of H1N1 infection and mortality in younger age group. Conclusion: The Influenza A (H1N1) virus is still present two years after year 2009-10 pandemic. It has become a ubiquitous virus in the districts of Western Rajasthan region of India. In the event of new influenza outbreaks, hygienic and containment measures must be quickly and correctly implemented in order to avoid an epidemic.

Expression of Syndecan-1 and HPA-1 and their relationship with the invasion and metastasis of gastric carcinoma / 中国癌症杂志

Background and purpose: Syndecan-1 and HPA-1 may be involved in the progression of invasion and metastasis of many malignant tumors, but there are few reports about the relationship between the two gene expressions in gastric carcinomas. This study was aimed to explore the expression of Syndecan-1 and HPA-1 mRNA in gastric carcinoma and their relationship with the invasion and metastasis of gastric carcinoma. Methods: Real-time polymerase chain reation (RT-PCR) was used to detect mRNA of Syndecan-1 and HPA-1 in 58 cases of gastric carcinoma, 58 paired adjacent gastric carcinoma (2 cm from carcinoma), and 58 surgical marginal normal gastric mucosa tissues (5 cm from carcinoma). Then we analyzed their relationship with clinico-pathological characteristics of gastric carcinoma. Results: The upregulation of Syndecan-1 mRNA was significantly higher in normal gastric mucosa (98.3%) than that in paired adjacent mucosa (25.9%) and gastric carcinoma (5.2%) (all P<0.001).The upregulation of Syndecan-1 mRNA was significantly higher in paired adjacent mucosa than that in gastric carcinoma (all P<0.05). The upregulation of HPA-1 mRNA was significantly higher in gastric carcinoma (86.2%) than that in paired adjacent gastric carcinoma (27.6%) and normal gastric mucosa (5.2%) (P<0.001). The upregulation of HPA-1 mRNA was significantly higher in paired adjacent gastric carcinoma than that in normal gastric mucosa (all the same P<0.05). The downregulation of Syndecan-1 and the upregulation of HPA-1 had relationship with the degree of differentiation, depth of infiltration, lymph node metastasis, distant metastasis and TNM staging of gastric carcinoma (P<0.05). Conclusion: The upregulation of Syndecan-1 mRNA was significantly higher in normal gastric mucosa. The upregulation of HPA-1 mRNA was significantly higher in gastric carcinoma. Also, the expression of Syndecan-1 and HPA-1 could predict the invasion and metastasis of gastric carcinoma. Determination of Syndecan-1 and HPA-1 may be of value in the treatment as well as in the prediction for prognosis of gastric cancer.