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Background and Objectives: Methicillin resistance is acquired by the bacterium due to mecA gene which codes for penicillin-binding protein (PBP2a) having low affinity for ß-lactam antibiotics. mecA gene is located on a mobile genetic element called staphylococcal cassette chromosome mec (SCCmec). SCCmec genomic island comprises two site-specific recombinase genes namely ccrA and ccrB [cassette chromosome recombinase] accountable for mobility. Currently, SCCmec elements are classified into types I, II, III, IV and V based on the nature of the mec and ccr gene complexes and are further classified into subtypes according to variances in their J region DNA. SSCmec type IV has been found in community-acquired isolates with various genetic backgrounds. The present study was undertaken to categorize the types of SCCmec types and subtypes I, II, III, IVa, b, c, d, and V and PVL genes among clinical MRSA isolates from COVID-19 confirmed cases. Materials and Methods: Based on the Microbiological and Molecular (mecA gene PCR amplification) confirmation of MRSA isolated from 500 MRSA SCCmec clinical samples, 144 cultures were selected for multiplex analysis. The multiplex PCR method developed by Zhang et al. was adapted with some experimental alterations to determine the specific type of these isolates. Results: Of the total 500 MRSA, 144 MRSA (60 were CA-MRSA and 84 were HA-MRSA) were selected for characterization of novel multiplex PCR assay for SSCmec Types I to V in MRSA. Molecular characterization of multiplex PCR analysis revealed results compare to the phenotypic results. Of the 60 CA-MRSA; in 56 MRSA strains type IVa was found and significantly defined as CA-MRSA while 4 strains showed mixed gens subtypes. Type II, III, IA, and V were present in overall 84 HA-MRSA. Molecular subtyping was significantly correlated to define molecularly as CA-MRSA and HA-MRSA however 15 (10%) strains showed mixed genes which indicates the alarming finding of changing epidemiology of CA-MRSA and HA-MRSA as well. Conclusion: We have all witnessed of COVID-19 pandemic, and its mortality was mostly associated with co-morbid conditions and secondary infections of MDR pathogens. Rapid detections of causative agents of these superbugs with their changing epidemiology by investing in typing and subtyping clones are obligatory. We have described an assay designed for targeting SSCmec types and subtypes I, II, III, IVa,V according to the current updated SCCmec typing system. Changing patterns of molecular epidemiology has been observed by this newly described assay.
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BACKGROUND: Cellulases are well known for their various industrial applications. They are naturally produced by different species of bacteria and fungi. Fermentation process of cellulase producers has limitation due to the high substrate cost required for cellulase induction and challenges to maintain the suitable condition for the respective cellulase production. Recombinant cellulase production could be the potential solution to these problems. In the current study, we investigated recombinant cellulase expression in Escherichia coli using cellulase gene from Bacillus subtilis. RESULTS: Extracellular cellulase production from B. subtilis strain was first confirmed on CMC agar and then the cellulase gene (1500 bp) was amplified from this strain and was further cloned in pET21a expression vector. In initial experimental studies, recombinant cellulase expression was achieved in inclusion bodies through shake flask level fermentation of transformed E. coli expression host BL21DE3. Attempts were made to express this 55 KDa His tagged recombinant cellulase into soluble form by modifications in fermentation conditions. Partially purified recombinant cellulase was obtained using Ni-NTA affinity chromatography. The activity of the purified enzyme was confirmed by 3,5-dinitrosalicylic acid (DNS) qualitative assay. CONCLUSION: Soluble expression of active recombinant cellulase can be achieved by subtle alteration in the upstream process.
RESUMEN
With COVID-19 declared as a worldwide pandemic, a nationwide lockdown was implemented overnight in India on March 24, 2020. With no prior warning or anticipation, patient appointments were temporarily ceased as institutions and clinics were indefinitely closed. To our knowledge, no study addresses the orthodontic patient perspective in such testing times, where they are entirely restricted to the confines of their homes. AIM: To assess the impact of the COVID-19-related lockdown on the treatment and psychology of patients undergoing orthodontic treatment. MATERIAL AND METHODS: A self-designed online exploratory questionnaire of 15 questions was distributed to 500 potential responders selected from obtained lists through messages and emails. It was mandatory to answer all questions and the survey was anonymized and did not contain any identifying information. Online consent was taken before participation in the study. The obtained data were evaluated using descriptive and inferential statistics. RESULTS: The response rate was 81.6%. The study revealed that the majority of patients were affected by the lack of access to orthodontic visits. The reasons for the same were attributed to fear of increased treatment duration, inconveniences caused by poking wires, broken brackets, etc., and lack of communication between the orthodontists and patients, among the various other reasons. The importance of orthodontic appointments was also understood by patients. CONCLUSION: The study threw light on the essential need for understanding the psychology of patients undergoing orthodontic treatment. In any situation where patients do not have access to seek help, all the factors discussed in the study should be considered and it is of utmost importance that orthodontic professionals see to it that their patients are being looked after mentally, if not physically, in whatever way possible.