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Purpose: To investigate the expression of lncRNA MALAT1-targeting miR-570-3p and miR-34a and its effects on the invasion, proliferation, and apoptosis of human retinoblastoma cells. Methods: MiR-34a, miR-570-3p, and IncRNA MALAT1 in a human normal retinal vascular endothelial cell line (ACBRI-181), human retinoblastoma cell line (SO-Rb50), human normal retinal tissue and human retinoblastoma tissue were determined. Luciferase assay was used to verify the targeting relationship between LncRNA MALAT1 and miR-570-3p and miR-34a. while cell invasion, cell apoptosis and cell proliferation were assessed by Transwell assay, flow cytometry, and tumor pellet-forming assay, respectively. Results: LncRNA MALAT1 in SO-Rb50 cell line and human retinoblastoma tissue line were significantly up-regulated, while the expression levels of miR-34a and miR-570-3p were significantly down-regulated (p < 0.05). Luciferase assay results showed that lncRNA MALAT1 targeted miR-570-3p and miR-34a. The invasion and proliferation of SO-Rb50 cells in the miR-570-3p inhibitor and miR-34a inhibitor groups were significantly increased, while the apoptosis of SO-Rb50 cells was significantly decreased (p < 0.05). However, the invasion and proliferation of SO-Rb50 cells in sh-MALAT1 group were significantly decreased, while apoptosis significantly increased. However, compared with sh-MALAT1 group alone, the invasion and proliferation of SO-Rb50 cells in co-transfected sh-MALAT1+miR-570-3p inhibitor + miR-34a inhibitor group w significantly increased, but apoptosis significantly decreased (p < 0.05). Conclusion: LncRNA MALAT1 negatively regulates miR-570-3p and miR-34a to promote the invasion and proliferation of human retinoblastoma SO-Rb50 cells and inhibit apoptosis. These findings may be of significance in developing suitable therapies for human retinoblastoma

Summary Objective The hepatitis B vaccine was first introduced into the routine immunization program in Henan Province, China in 1992. In 2012, a survey was conducted to evaluate the protective effects of hepatitis B vaccination for the populations born during the preceding 15 years. Methods A multistage stratified random cluster sampling method was used to collect samples. The participants were interviewed and relevant information was obtained for the population aged 1 to 14 years using a standardized questionnaire; a 2- or 3-ml serum sample was taken from each participant to measure hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc). Association and logistic regression analyses were conducted to determine relationships between these parameters. Results A total of 13 207 residents aged 1 to 14 years residing in 60 villages or communities in Henan, China were surveyed and had their blood collected. Serological analysis revealed that the HBsAg and anti-HBc prevalences were 0.8% and 2.6%, respectively. The HBsAg prevalence among children under 5 years of age was 0.5%, showing a decline of 96% compared to the average national HBsAg prevalence in 1992. Children had a higher likelihood of HBsAg positivity if they had an HBsAg-positive family member (odds ratio (OR) 4.26), no history of vaccination (OR 2.06), were born in a smaller township hospital or at home (OR 1.61), were aged 10–14 years (OR 2.07), or were living in a rural area (OR 2.01). Conclusions The HBsAg prevalence rate in persons under 15 years of age has dropped significantly in Henan Province after two decades of vaccination. Thus millions of chronic HBV infections have been prevented.

Soil microbial communities probably are the most complex of natural communities, and one study estimated that there may be as many as 1,000,000 “distinct genomes” per g of soil. This chapter is divided into two sections, the first covering approaches that require laboratory cultivation or incubation and the second addressing those based on analysis of indicator molecules that have been extracted directly from soil communities. A commonly used approach for identification of environmental isolates is based on growth on specific substrates and fermentative abilities. A more precise method of determining the phylogenetic affiliation of an isolate is by characterization of its rRNA. The technique is based on the concept that rRNA molecules, particularly the 16S and 23S rRNA molecules of prokaryotes, are highly conserved throughout evolution and are therefore useful as specific indicators of the phylogenetic affiliations of environmental isolates. A variety of DNA fingerprinting techniques can be used to rapidly differentiate closely related environmental strains. Regardless of the specific technique, the data obtained are DNA fragments that, when separated on agarose or polyacrylamide gels, yield a banding pattern specific to the genome under investigation. Rapid screening methods are of three categories that include: denaturing gradient gel electrophoresis (DGGE), temperature gradient gel electrophoresis (TGGE), and terminal restriction fragment length polymorphism (T-RFLP) analysis. The chapter talks about automated ribosomal intergenic spacer analysis (ARISA). An alternative approach to soil microbial community analysis is cloning of the soil “metagenome,” defined as the genomes of the total microbiota found in soils.

The genome of Leishmania mexicana encompasses a cluster of three glucose transporter genes designated LmxGT1, LmxGT2 and LmxGT3. Functional and genetic studies of a cluster null mutant (Δlmxgt1-3) have dissected the roles of these proteins in Leishmania metabolism and virulence. However, null mutants were recovered at very low frequency, and comparative genome hybridizations revealed that Δlmxgt1-3 mutants contained a linear extrachromosomal 40 kb amplification of a region on chromosome 29 not amplified in wild type parasites. These data suggested a model where this 29-40k amplicon encoded a second site suppressor contributing to parasite survival in the absence of GT1-3 function. To test this, we quantified the frequency of recovery of knockouts in the presence of individual overexpressed open reading frames covering the 29-40k amplicon. The data mapped the suppressor activity to PIFTC3, encoding a component of the intraflagellar transport pathway. We discuss possible models by which PIFTC3 might act to facilitate loss of GTs specifically. Surprisingly, by plasmid segregation we showed that continued PIFTC3 overexpression was not required for Δlmxgt1-3 viability. These studies provide the first evidence that genetic suppression can occur by providing critical biological functions transiently. This novel form of genetic suppression may extend to other genes, pathways and organisms.