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Drug-resistant tuberculosis (DR-TB) is a major contributor to global cases of antimicrobial resistance and remains a public health challenge. To understand the extent and trend of DR-TB under an enhanced multidrug-resistant TB (MDR-TB) management program, we conducted a population-based retrospective study of 1511 Taiwanese MDR-TB cases reported from 2008 to 2019.

Pepsin is widely used for the extraction of pepsin-solubilized collagens (PSC) from many resources. PSC-A and PSC-P were prepared from carp skin using 0.1 mol L−1 acetic acid and 0.02 mol L−1 Na2HPO4 (pH 7.2) as the dialysis solution, respectively. SDS-PAGE patterns showed PSC-A and PSC-P as type I collagens, as well as acid soluble collagen (ASC). When incubated at 40°C, no degradation was observed for ASC, but PSC-A and PSC-P were degraded into short peptides, showing lower stability than ASC. The results indicate that pepsin remaining in the PSCs resulted in their degradation, which was confirmed by the inhibition using pepstatin. This research revealed the behavior of the remaining pepsin in pepsin-solubilized collagens and an approach to the PSC stability improvement was proposed. Chromatography profiles showed that new PSC prepared by the improved method had almost the same stability as ASC.

ABSTRACTRapid assays are still needed to detect rifabutin (RFB) susceptibility for proper tuberculosis treatment. To assess the use of the GenoType MTBDRplusassay and subsequent rpoBgene sequencing on detection of RFB susceptibility, we analyzed 800 multidrug-resistant Mycobacterium tuberculosisisolates, and 13% (104/800) were RFB susceptible. Of the 104 RFB-susceptible isolates, 71 (68.3%) isolates were rapidly identified using two molecular assays, while the remaining isolates could be determined using conventional drug-susceptibility testing according to the clinician's decision.

ABSTRACTThe GenoType MTBDRsltest and DNA sequencing were used to rapidly detect second-line drug- and ethambutol (EMB)-resistant Mycobacterium tuberculosis. The ability of these two assays to detect the presence of mutations associated with resistance to fluoroquinolones (FLQ), aminoglycosides/cyclic peptide (AG/CP), and EMB in the gyrA, rrs, and embBgenes (for the GenoType MTBDRsltest) and gyrA, gyrB, rrs, eis, embC, embA, embB, and embRgenes (for DNA sequencing) was compared to that of conventional agar proportion drug susceptibility testing (DST). We evaluated 234 multidrug-resistant (MDR) M. tuberculosisisolates. The two molecular methods had high levels of specificity (95.8 to 100%). The sensitivities for FLQ resistance detection for both methods were 85.1%. For AG (kanamycin [KM] and amikacin [AM]) and CP (capreomycin CAP]), the sensitivities of resistance detection using the GenoType MTBDRsltest were 43.2%, 84.2%, and 71.4%, respectively, while with the inclusion of an extra gene, eis, in sequencing, the sensitivity reached 70.3% for detection of KM resistance. The sensitivities of EMB resistance detection were 56.2% and 90.7% with the GenoType MTBDRsltest and sequencing, respectively. We found that the GenoType MTBDRsltest can rapidly detect resistance to FLQ, CAP, and AM. The accuracy of the GenoType MTBDRsltest for the detection of FLQ and AM resistance was comparable to that of conventional DST; however, the test was less accurate for the detection of KM and EMB resistance and demonstrated a poor predictive value for CAP resistance. We recommend including new alleles consisting of the eispromoter and embBgenes in molecular analysis. However, conventional DST is necessary to rule out false-negative results from molecular assays.

ABSTRACTA culture confirmation test for the detection of Mycobacterium tuberculosiscomplex strains that uses a lateral-flow immunochromatographic assay to detect the MPB64 antigen, the MGIT TBc identification (TBc ID) test, has been developed. We evaluated the performance of the TBc ID test in the detection of the M. tuberculosiscomplex in 222 primary-positive liquid cultures. We compared these results to those of nucleic acid-based identification and conventional biochemical tests. The validity of the TBc ID test was determined, and all of the nontuberculous mycobacteria (NTM) and Nocardiaspecies tested were found to be negative. The detection limit of the TBc ID test was 5 × 105CFU/ml, and for IS6110real-time PCR it was 5 CFU/ml. All of the M. tuberculosisand M. africanumcultures were found to be positive, while M. bovisand M. bovisBCG cultures were negative. With the exception of 1 contaminated culture, the 221 culture-positive isolates contained 171 (77.5%) M. tuberculosisisolates, 39 (17.6%) NTM species, and 11 (5.0%) unidentified species. Two culture-positive isolates harbored a 63-bp deletion at position 196 of the mpb64gene. The sensitivity, specificity, positive predictive values, and negative predictive values of the TBc ID test were 98.8, 100, 100, and 95.1%, respectively. Furthermore, the approximate turnaround time for real-time PCR was 4 h (including buffer and sample preparation), while for the TBc ID test it was less than 1 h. We suggest an algorithm for the primary identification of M. tuberculosisin liquid culture using the TBc ID test as an alternative to conventional subculture followed by identification using biochemical methods.

The aim of this study was to investigate the situations and factors that cause nurses not to follow standard operating procedures (SOPs) during the clinical trial process.

ABSTRACTAs is widely recognized, CD8+cytotoxic T lymphocytes (CTLs) play a crucial role in hepatitis C virus (HCV) infection, both in pathogenesis of liver injury and in clearing the virus. CTL studies with HCV-infected patients have been difficult because of the relatively low frequency of CTL precursors in the peripheral blood and because the targeted epitopes vary depending on the human leukocyte antigen (HLA) types of the individuals. This study attempts to overcome these problems by assessing the feasibility of using autologous peripheral blood mononuclear cells (PBMCs) expressing viral antigens as stimulators or targets in order to monitor the CTL responses. Primary PBMCs were transduced using a retroviral vector pseudotyped with a vesicular stomatitis virus G glycoprotein expressing the HCV core gene. Additionally, the vector-transduced PBMCs were used as targets of CTL assays to measure the HCV core-specific CTL activities from the liver-infiltrating lymphocytes of six different HLA-type patients with chronic HCV infection. The core-expressing PBMCs also served as stimulators, allowing us to measure core-specific CD8+T-cell responses by intracellular gamma interferon staining of the peripheral blood of hepatitis C patients who had received treatment with alpha interferon plus ribavirin. This approach provides an efficient means of measuring antigen-specific CTL responses without HLA constraints.