The microbiota of the nasopharyngeal tract (NT) play a role in host immunity against respiratory infectious diseases. However, scant information is available on interactions of SARS-CoV-2 with the nasopharyngeal microbiome. This study characterizes the effects of SARS-CoV-2 infection on human nasopharyngeal microbiomes and their relevant metabolic functions. Twenty-two (n = 22) nasopharyngeal swab samples (including COVID-19 patients = 8, recovered humans = 7, and healthy people = 7) were collected, and underwent to RNAseq-based metagenomic investigation. Our RNAseq data mapped to 2281 bacterial species (including 1477, 919 and 676 in healthy, COVID-19 and recovered metagenomes, respectively) indicating a distinct microbiome dysbiosis. The COVID-19 and recovered samples included 67% and 77% opportunistic bacterial species, respectively compared to healthy controls. Notably, 79% commensal bacterial species found in healthy controls were not detected in COVID-19 and recovered people. Similar dysbiosis was also found in viral and archaeal fraction of the nasopharyngeal microbiomes. We also detected several altered metabolic pathways and functional genes in the progression and pathophysiology of COVID-19. The nasopharyngeal microbiome dysbiosis and their genomic features determined by our RNAseq analyses shed light on early interactions of SARS-CoV-2 with the nasopharyngeal resident microbiota that might be helpful for developing microbiome-based diagnostics and therapeutics for this novel pandemic disease.

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic which has brought a great challenge to public health. After the first emergence of novel coronavirus SARS-CoV-2 in the city of Wuhan, China, in December 2019. As of March 2020, SARS-CoV-2 was first reported in Bangladesh and since then the country has experienced a steady rise in infections, resulting in 13,355,191 cases and 29,024 deaths as of 27 February 2022. Bioinformatics techniques are used to predict B cell and T cell epitopes from the new SARS-CoV-2 spike glycoprotein in order to build a unique multiple epitope vaccine. The immunogenicity, antigenicity scores, and toxicity of these epitopes were evaluated and chosen based on their capacity to elicit an immune response. Result The best multi-epitope of the possible immunogenic property was created by combining epitopes. EAAAK, AAY, and GPGPG linkers were used to connect the epitopes. In several computer-based immune response analyses, this vaccine design was found to be efficient, as well as having high population coverage. Conclusion This research is entirely reliant on the development of epitope-based vaccines, and these in silico findings would represent a major step forward in the development of a vaccine that might eradicate SARS-CoV-2 in Bangladeshi patients.

An efficient in vitro regeneration system was developed for Rauvolfia serpentina L. through direct and indirect organogenesis from nodal and leaf explants. Among the different growth regulators, MS medium supplemented with 2.0 mg/l BAP, 0.5mg/l IAA and 0.02mg/l NAA found best for the multiple shoot formation from nodal segments. In this combination 98% explants produced multiple shoots and the average number of shoots per explants is 13∙4. The frequency of callus induction and multiple shoot induction from leaves was highest 88% in MS medium supplemented with 2.0 mg/l BAP, where mean number of shoots/explants was 12.5. The highest frequency of root induction (80%) and mean number of roots/plantlets (10) were obtained on half strength of MS medium containing 0.2 mg/l IBA. The rooted plantlets were transferred for hardening following acclimatization and finally were successfully established in the field.Bangladesh J. Sci. Ind. Res.53(2), 133-138, 2018

An efficient rapid in vitro regeneration protocol was described from nodal segment, leaf and petiole explants. MS medium supplemented with 1.0 mg/l BAP and 0.5 mg/l IAA was found best for the multiple shoot formation from nodal segments. In this combination 99% explants produced multiple shoots and the average number of shoots per explants was 20.1 ± 1.96. For petiole and leaf explants best response was observed on MS supplemented with 2.0 mg/l BAP, 1 mg/l IAA and 0.5 mg/l Kn. Petiole explants produced highest mean number of shoots/explant (22.9 ± 1.728) among the three explants when the explants were cultured on MS with 2.0 mg/l BAP, 1 mg/l IAA and 0.5 mg/l Kn. The highest frequency of root induction (100%) and mean number of roots/plantlets (11.75) were obtained on MS. The rooted plantlets were transferred for hardening following acclimatization and finally were successfully established in the field.

We report the sequencing of three severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes from Bangladesh. We have identified a unique mutation (NSP2_V480I) in one of the sequenced genomes (isolate hCoV-19/Bangladesh/BCSIR-NILMRC-006/2020) compared to the sequences available in the Global Initiative on Sharing All Influenza Data (GISAID) database. The data from this analysis will contribute to advancing our understanding of the epidemiology of SARS-CoV-2 in Bangladesh as well as worldwide at the molecular level and will identify potential new targets for interventions.