The MTBDRplus line probe assay (LPA) and Xpert MTB/RIF have been endorsed by the World Health Organization for the rapid diagnosis of drug-resistant tuberculosis. However, there is no clarity regarding the superiority of one over the other. In a double-blinded prospective study, we evaluated the efficacy of the Xpert MTB/RIF on samples that were first tested by LPA under the revised national tuberculosis control program of India. A total of 405 sputum samples from suspected drug-resistant tuberculosis patients were included. Of these, 285 smear-positive samples were subjected to LPA. Seventy-two (25.8%) samples showed multidrug resistance, 62 (22.2%) showed rifampin monoresistance, 29 (10.3%) showed isoniazid monoresistance, and 116 (41.5%) were pan-susceptible. Six (2.1%) of the samples gave invalid results. Of the 62 rifampin-monoresistant samples by LPA, 38 (61.4%) showed rifampin resistance, while 21 (33.8%) were found susceptible to rifampin by Xpert MTB/RIF using cartridge version G4. Three (4.8%) samples gave an error. Of the 116 pan-susceptible samples, only 83 were available for Xpert MTB/RIF testing; 4 (5.1%) were rifampin resistant, 74 (94.8%) were susceptible, and 5 (6.0%) showed an error. The 25 discrepant samples were further subjected to MGIT960 drug susceptibility testing. The MGIT960 results showed 100% agreement with LPA results but only 64.4% agreement with Xpert MTB/RIF results. Sequencing analysis of discrepant samples showed 91.3% concordance with LPA but only 8.7% concordance with the Xpert MTB/RIF assay. These findings indicate that by using Xpert MTB/RIF testing we might be underestimating the burden of drug-resistant tuberculosis and indicate that country-specific probes need to be designed to increase the sensitivity of the Xpert MTB/RIF. T he global burden of tuberculosis (TB), particularly with multidrug resistance (MDR), is increasing and has become a major health challenge (1). The disease caused by Mycobacterium tuberculosis resistant to two primary antitubercular drugs, rifampin (RIF) and isoniazid (INH), is known as MDR-TB. Such instances are more common among clinical relapse cases (2). It has been reported that M. tuberculosis that is resistant to RIF is more likely to have concomitant resistance to INH, making RIF resistance a surrogate marker of MDR-TB (3). Early diagnosis of TB and rapid detection of RIF resistance is important for proper management of drug-resistant TB (DR-TB) (4). But in spite of major efforts that are being done to increase case detection, one-third of new TB cases are still missed due to nonavailability of rapid, low-cost, and accurate diagnostic facilities in high-TB-burden countries (5).Over the last 6 years, efforts have been made to improve and develop rapid diagnostic tools and drug susceptibility testing (DST) for TB. During this period, the World Health Organization (WHO) had issued 10 policy statements for improving diagnosis of TB, including the use of commercial and noncommercial DST methods and implementation of molecular methods such as the ...

BackgroundTuberculosis (TB) in children is neglected, mainly due to lack of sensitive diagnostic tools. Recently Xpert MTB/RIF assay has revolutionized the diagnostic field, but its usefulness in pediatric TB has not been reported from India and no report is available on its use on long term archived samples.MethodsWe recruited 130 pediatric patients with probable intrathoracic tuberculosis and their gastric aspirate (GA) and induced sputum (IS) samples on 2 consecutive days were collected between January 2009 and December 2012. All samples (n = 520) were subjected to smear examination, BACTEC-MGIT culture and in-house multiplex PCR. An aliquot of each sample was stored at −80 °C and tested in Xpert MTB/RIF assay in 2013.ResultsSample wise and patient wise detection rate of smear microscopy was 4.4 % and 10 %, while for BACTEC-MGIT culture this rate was 24.4 % and 46.9 %, respectively. Of the 130 day 1 GA samples, 31.5 % and 27.7 % day 2 GA samples were culture positive. Only 17.7 % GA samples were positive on both days. Of the 130 IS samples collected on day 1 and day 2, 15.4 % and 23.1 % samples were culture positive. A combination of GA and IS yielded best results. Combining both GA and IS, the overall sensitivity of Xpert MTB/RIF on smear and culture positive samples was 95.6 %. In smear negative and culture positive samples its sensitivity was 62.5 %. The duration of sample storage impacted the Xpert MTB/RIF test performance (p = 0.0001). In smear positive samples stored for 650–849 days, its sensitivity was 85.7 % and 77.1 % for IS and GA samples which dropped to 33.3 % and 50 %, respectively, if stored for more than 1050 days.DiscussionConfirmatory diagnosis of tuberculosis particularly in children is a medical challenge. No laboratory or radiological test can reach to a satisfactory level of diagnostic sensitivity. However, in this study we foundthat combination of multiple samples and multiple diagnostic tests can give much better yield, though notoptimum. In present study, combination of 2 gastric aspirates (GA) and 2 induced sputum (IS) samples collected on two consecutive days, and tested on three diagnostic methods yielded a significantly high detection rate. Despite long term storage, the overall sensitivity of Xpert MTB/RIF on smear and -culture positive samples remained very high. But after storing these samples under subfreezing conditions thesensitivity of Xpert MTB/RIF decreased significantly. This is expected because even if the sample is smear and culture positive, the count of surviving mycobacteria goes down, after several years this count can reach to a undetectable level.ConclusionThis report shows that smear and culture positive samples stored at subfreezing conditions for several years can be used in the Xpert MTB/RIF assay, while maintaining appreciable diagnostic test sensitivity and specificity.

In the 21 st century, human civilization, has witnessed three major epidemics caused by Coronaviruses namely severe acute respiratory syndrome coronavirus (SARS-CoV) in 2003, Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012 and 2019-novel coronavirus (2019-nCoV) or coronavirus disease (COVID-19) in 2019. Among these, COVID-19 has greater transmission and mortality rate. 2019-nCoV belongs to a large family of positive sense single-stranded RNA viruses (+ssRNA) that can be isolated in different animal species. The most communal symptoms of COVID-19 include fever, cough, and shortness of breath during the incubation period (2-14 days) of infection. COVID-19 transmission is occurring from infected humans to close contact with one another through respiratory droplets, coughs, and sneezes of infected person. Moreover, the virus containing surfaces may also transmit the infection. Diagnosis is being carried out by collecting a nasopharyngeal swab or sputum specimen for detection of SARS-CoV-2 RNA by reverse-transcription polymerase chain reaction (RT-PCR). Rapid diagnosing methods are also under development which can diagnose COVID 19 in few minutes to hours. Currently, there is no specific cure or preventive therapeutics available. Hence, based upon limited in-vitro and anecdotal data, Chloroquine, or Hydroxychloroquine, Remdesivir, Lopinavir and Ritonavir are being employed in the management. Search for new specific anti-viral drugs from natural/synthetic origins is under full swing and many of them are currently used as chemotherapeutic drugs under clinical investigation. Yet, there is a strong need for development of vaccine, which may take several months to few years for the development.

Surface activation of polyethylene (PE) samples has been carried out using low pressure plasmas (at two different operating frequencies, namely, 40 kHz and 13?56 MHz) and dielectric barrier discharge (DBD) (50 Hz frequency and at atmospheric pressure), and the results are compared. The surface of the PE samples has been exposed to these different plasmas for various time durations ranging from 1 to 30 min. The treated samples have also been studied for their aging behaviour by exposing them to the ambient atmosphere for up to 7 days. The plasma induced morphological changes were studied using an scanning electron microscope and an atomic force microscope, while the formation of various functional groups was identified using Fourier transform infrared analysis. The surface energy values were observed to increase from 27?5 dyne cm 21 (of untreated PE) to 73?8 and 52?2 dyne cm 21 after low pressure 40 kHz and 13?56 MHz air plasma treatment respectively and to 35?6 dyne cm 21 after the DBD air plasma treatment. The low pressure plasma treatment at an operating frequency of 40 kHz has produced the best results in the surface activation of PE. During the aging process, the formation of C5C bonds was observed on the surface of PE.

Differences in the incidence and outcome of glioma between males and females are well known, being more striking for glioblastoma (GB) than low-grade glioma (LGG). The extensive and well-annotated data in publicly available databases enable us to analyze the molecular basis of these differences at a global level. Here, we have analyzed The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases to identify molecular indicators for these gender-based differences by different methods. Based on the nature of data available/accessible, the transcriptomic profile was studied in TCGA by using DeSeq2 and in CGGA by T-test, after correction based. Only IDH1 wild-type tumors were studied in CGGA. Using weighted gene co-expression network analysis (WGCNA), network analysis was done, followed by the assessment of modular differential connectivity. Differentially affected signaling pathways were identified. The gender-based effects of differentially expressed genes on survival were determined. DNA methylation was studied as an indicator of gender-based epigenetic differences. The results clearly showed gender-based differences in both GB and LGG, whatever method or database was used. While there were differences in the results obtained between databases and methods used, some major signaling pathways such as Wnt signaling and pathways involved in immune processes and the adaptive immune response were common to different assessments. There was also a differential gender-based influence of several genes on survival. Also, the autosomal genes NOX, FRG1BP, and AL354714.2 and X-linked genes such as PUDP, KDM6A, DDX3X, and SYAP1 had differential DNA methylation and expression profile in male and female GB, while for LGG, these included autosomal genes such as CNIH3 and ANKRD11 and X-linked genes such as KDM6A, MAOB, and EIF2S3. Some, such as FGF13 and DDX3X, have earlier been shown to have a role in tumor behavior, though their dimorphic effects in males and females have not been identified. Our study thus identifies several crucial differences between male and female glioma, which could be validated further. It also highlights that molecular studies without consideration of gender can obscure critical elements of biology and emphasizes the importance of parallel but separate analyses of male and female glioma.