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NK cells augment oncolytic adenovirus cytotoxicity in ovarian cancer

Oncolytic viruses (OVs) can trigger profound innate and adaptive immune responses, which have the potential both to potentiate and reduce the activity of OVs. Natural killer (NK) cells can mediate potent anti-viral and anti-tumoral responses, but there are no data on the role of NK cells in oncolytic adenovirus activity. Here, we have used two different oncolytic adenoviruses—the Ad5 E1A CR2-deletion mutant dl922-947 (group C) and the chimeric Ad3/Ad11p mutant enadenotucirev (group B)—to investigate the effect of NK cells on overall anti-cancer efficacy in ovarian cancer. Because human adenoviruses do not replicate in murine cells, we utilized primary human NK cells from peripheral blood and ovarian cancer ascites. Our results show that dl922-947 and enadenotucirev do not infect NK cells, but induce contact-dependent activation and anti-cancer cytotoxicity against adenovirus-infected ovarian cancer cells. Moreover, manipulation of NK receptors DNAM-1 (DNAX accessory molecule-1) and TIGIT (T cell immunoreceptor with Ig and ITIM domains) significantly influences NK cytotoxicity against adenovirus-infected cells. Together, these results indicate that NK cells act to increase the activity of oncolytic adenovirus in ovarian cancer and suggest that strategies to augment NK activity further via the blockade of inhibitory NK receptor TIGIT could enhance therapeutic potential of OVs

Molecular characterization of the Chinese isolates of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) and the construction and characterization of the DNA vaccines

The genomic regions encoding ORFs 5 and 6 of the Chinese isolates named as AV strain of PRRSV found in Guangzhou are chosen and cloned into the mammalian expression vector pcDNA3.1(+) so as to construct the DNA vaccine. The objectives of this study are to first characterize this AV strain PRRSV emerged in Guangzhou, sequences based on ORF 5 and 6 were served as reference for further phylogenetic studies on the difference with North American (VR-2332) and the European (LV) strains. Investigation further focuses on the role of DNA vaccine constructed based on AV strain PRRSV in the generation of both humoral and lymphoproliferation immune responses and the possibility of using crude bacteria as adjuvant. Immunization with plasmid encoding ORF 5 or ORF 6 of AV strain PRRSV, with or without crude bacteria as adjuvant, induced anti-ORF 5 neutralizing antibodies or ORF 6 specific antibodies in both Balb/c mice and its natural host, pigs (trial experiment). Animals vaccinated with crude bacteria conjugated with ORF 5 encoded plasmid elicited stronger (which is around 80% more) and faster antibody responses than with plasmid construct alone as measured by ELISA. In addition, the increase in the number of blood lymphocytes obtained from vaccinated mice and pigs indicates the specificity of the lymphoproliferation responses to ORF 5-envelope protein & ORF 6 matrix protein. In summary, it demonstrates that ORF 5 & 6 plasmid construct with crude bacteria as adjuvant may be a potential candidate against this regional AV strain PRRSV isolated from Guangzhou, China

Characterization of Guangzhou Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Field Isolates

A direct method was used to detect the presence of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) in tissue samples of infected pigs collected from different farms in Guangzhou, based on reverse transcription of the viral RNA coupled to DNA amplification by polymerase chain reaction (RT-PCR). Several sets of primers were designed based on both the North American (VR-2332) and the European (LV) genome sequences within ORF1b encoding the polymerase protein in order to perform a rapid multiplex PCR assay. DNA products with unique size characteristics of each genotype were obtained. From three (named D2, D3 & AV) Guangzhou field isolates, amplified fragment of 108 bp was cloned and sequenced. Alignment with North American strain (VR-2332) sequences revealed a 95.5% homology. Among all, AV Guangzhou strain tissue homogenates were inoculated into MARC-145 cells and after the sixth passage, cytopathic effects (CPE) of infected cell were observed. Analysis of purified virions of AV Guangzhou strain by SDS-PAGE and western immunoblotting using porcine hyperimmune sera revealed that four major viral proteins: 15, 19, 26 and 45 kDa proteins

Identification by 16S ribosomal RNA gene sequencing of an Enterobacteriaceae species with ambiguous biochemical profile from a renal transplant recipient

Traditional ways of identification of bacteria by phenotypic characteristics cannot be used for non-cultivable organisms and organisms with unusual biochemical profiles. In this study, an Enterobacteriaceae was isolated in pure growth from the mid-stream urine of a 67-year old renal transplant recipient with urinary tract infection. Conventional biochemical tests did not reveal a pattern resembling any known member of the Enterobacteriaceae family. The Vitek system (GNI+) showed that it was 18% Leclercia adecarboxylata and 55% Klebsiella ozaenae; whereas the API system (20E) showed that it was 99.8% Rahnella aquatilis. 16S ribosomal RNA gene sequencing showed that there was 7 base differences between the isolate and Enterobacter cloacae, 18 base differences between the isolate and Enterobacter asburiae, 17 base differences between the isolate and Enterobacter cancerogenus, 35 base differences between the isolate and K. ozaenae, 27 base differences between the isolate and L. adecarboxylata, and 72 base differences between the isolate and R. aquatilis, indicating that the isolate most closely resembled a strain of E. cloacae. Identification of the organism in this study is important, as the choice of antibiotics would be radically different. In this case, cephalosporins should be avoided regardless of in-vitro susceptibility as cephalosporins are well-known to select for AmpC derepressed mutants in Enterobacter, and previous administration of third-generation cephalosporins is more likely to be associated with multidrug resistant Enterobacter isolates than is administration of antibiotics that do not include a third-generation cephalosporin. © 2001 Elsevier Science Inc.link_to_subscribed_fulltex

The effect of fast reporting by amnio-PCR on anxiety levels in women with positive biochemical screening for Down syndrome - a randomized controlled trial

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Metadata Design of a Content Management System for Music Virtual Learning Environment

Virtual Learning Environment (VLE) uncovers a new learning space for students to start their learning in multidisciplinary subjects and provides an enormous storage for different types of learning materials. This brings not only the ease and flexibility to our learning, but also the challenges in organizing, managing, and controlling of information which is indispensable to the design of an effective online learning system. In particular, Music Information Retrieval (MIR) is an interdisciplinary science on the process of retrieving information from music related resources. Due to the unique application characteristics and various forms of music, appropriate design and application of metadata plays an important role for the MIR in such a Content Management System (CMS) as it would affect the comprehensiveness and effectiveness of the music information retrieval process. In this paper, the authors propose their ontology-based metadata scheme to address such requirements of a music VLE, based on the Dublin Core with modifications according to specific nature of the music learning materials. The metadata design of music resources aims to support students' daily music learning by providing instant and appropriate learning materials which enables cross-collection searching and enhances the sustainability of the contents over time

Practice of breastfeeding and factors that affect breastfeeding in Hong Kong

Objectives. To describe the patterns of and factors affecting breastfeeding and to find out any significant relationship between breastfeeding and health of the child. Design. Cohort study. Setting. Postnatal ward of the Prince of Wales Hospital. Participants. A total of 243 infants born in 1998 to 2001 at the hospital. Each infant was followed up for 3 years. Home visits were carried out at 3, 15, 24, and 36 months of age by medical students from the Chinese University of Hong Kong. A questionnaire was completed at each visit. Independent sample t-tests and Pearson Chi squared tests were used. Results. Of the 243 subjects, 213 provided data on the method of infant feeding. There were 66.7% of mothers initiating breastfeeding, with a median duration of 1 month. Only 13.4% met the World Health Organization's recommendations on breastfeeding. Breastfeeding was found to have a statistically significant relationship with (i) the infant's birth order and (ii) the mother's and father's education level. During follow-up, 44.6% of the infants were hospitalised but there was no significant relationship between breastfeeding and number of hospitalisations. Conclusions. The current breastfeeding rate in Hong Kong falls below expectations when compared with other developed nations. To raise this rate, more support is needed for families with parents having a lower education level or more than two children, as they are the least likely to breastfeed. This might be achieved by encouraging antenatal class attendance, counselling of husbands, and more support for breastfeeding from doctors.link_to_subscribed_fulltex