Social distancing to curb the COVID-19 pandemic has caused suspension of classroom teaching in all educational institutions. We implemented a novel online classroom platform at our institute to continue medical education. The program attracted encouraging feedback from the students. It may serve as a model for uninterrupted teaching and training during times of crisis.

Chinese hamster ribosomal protein S14 cDNA was used to recognize homologous human cDNA and genomic clones. Human and Chinese hamster S14 protein sequences deduced from the cDNAs are identical. Two overlapping human genomic S14 DNA clones were isolated from a Charon 28 placental DNA library. A fragment of single-copy DNA derived from an intron region of one clone was mapped to the functional RPS14 locus on human chromosome 5q by using a panel of human x Chinese hamster hybrid cell DNAs. The human S14 gene consists of five exons and four introns spanning 5.9 kilobase pairs of DNA. Polyadenylated S14 transcripts purified from HeLa cell cytoplasm display heterogeneous 5' ends that map within noncoding RPS14 exon 1. This precludes assignment of a unique 5' boundary of RPS14 transcripts with respect to the cloned human genomic DNA. Apparently HeLa cells either initiate transcription at multiple sites within RPS14 exon 1, or capped 5' oligonucleotides are removed from most S14 mRNAs posttranscription. In contrast to the few murine ribosomal protein and several other mammalian housekeeping genes whose structures are known, human RPS14 contains a TATA sequence (TATACTT) upstream from exon 1. Three related short sequence motifs, also observed in murine and yeast ribosomal protein genes, occur in this region of the RPS14 gene. RPS14 introns 3 and 4 both contain Alu sequences. Interestingly, the Alu sequence in intron 3 is located slightly downstream from a chromosome 5 deletion breakpoint in one human x hamster hybrid clone analyzed.Ribosomal proteins (r-proteins) are encoded by complex multigene families in eucaryotes and procaryotes. Several bacterial and yeast r-protein genes have been investigated by both biochemical and genetic approaches. Substantial evidence indicates that bacterial and yeast r-protein genes are stringently coregulated by transcriptional, translational, and posttranslational mechanisms (16, 18, 22, 31, 38-40, 42, 47, 59, 60, 66-68). A few r-protein genes have been isolated from the DNAs of higher eucaryotes-Drosophila melanogaster (8,14,41,57), Xenopus laevis (1, 6), mice (13, 43, 58, 63), rats (25, 36), and Chinese hamsters (34,35,45). For lack of appropriate genetic methods and markers, progress in elucidating mechanisms that regulate r-protein genes in these organisms has been slow. Despite this, recombinant DNA techniques permit us to distinguish active, intron-containing animal r-protein genes from processed pseudogenes (13,23,43,58,63) and indicate that they are regulated coordinately under a variety of experimental conditions (15,17,21,24,30,33,44,51,62).The gene encoding Chinese hamster 40S ribosomal subunit protein S14 is the only mammalian r-protein gene currently amenable to somatic genetic analysis in tissue culture. This gene is the target of emetine resistance mutations, as emtB Chinese hamster ovary (CHO) cell mutants elaborate altered S14 mRNAs and polypeptides (4,5,27,28,35,37,45). We have isolated Chinese hamster S14 and other r-protein cDNAs (35) and have demonstrated that emtB ...

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Pinostrobin (PN) is a naturally occurring dietary bioflavonoid, found in various medicinal herbs/plants. Though anti-cancer potential of many such similar constituents has been demonstrated, critical biochemical targets and exact mechanism for their apoptosis-inducing actions have not been fully elucidated. The present study was aimed to investigate if PN induced apoptosis in cervical cancer cells (HeLa) of human origin. It is demonstrated that PN at increasing dose effectivity reduced the cell viability as well as GSH and NO2- levels. Condensed nuclei with fragmented chromatin and changes in mitochondrial matrix morphology clearly indicated the role of mitochondria in PN induced apoptosis. A marked reduction in mitochondrial membrane potential and increased ROS production after PN treatment showed involvement of free radicals, which in turn further augment ROS levels. PN treatment resulted in DNA damage, which could have been triggered by an increase in ROS levels. Decrease in apoptotic cells in the presence of caspase 3 inhibitor in PN-treated cells suggested that PN induced apoptosis via caspase dependent pathways. Additionally, a significant increase in the expression of proteins of extrinsic (TRAIL R1/DR4, TRAIL R2/DR5, TNF RI/TNFRSF1A, FADD, Fas/TNFRSF6) and intrinsic pathway (Bad, Bax, HTRA2/Omi, SMAC/Diablo, cytochrome C, Pro-Caspase-3, Cleaved Caspase-3) was observed in the cells exposed to PN. Taken together, these observations suggest that PN efficiently induces apoptosis through ROS mediated extrinsic and intrinsic dependent signaling pathways, as well as ROS mediated mitochondrial damage in HeLa cells.