494 research outputs found
Update on rare epithelial ovarian cancers: based on the Rare Ovarian Tumors Young Investigator Conference
There has been significant progress in the understanding of the pathology and molecular biology of rare ovarian cancers, which has helped both diagnosis and treatment. This paper provides an update on recent advances in the knowledge and treatment of rare ovarian cancers and identifies gaps that need to be addressed by further clinical research. The topics covered include: low-grade serous, mucinous, and clear cell carcinomas of the ovary. Given the molecular heterogeneity and the histopathological rarity of these ovarian cancers, the importance of designing adequately powered trials or finding statistically innovative ways to approach the treatment of these rare tumors has been emphasized. This paper is based on the Rare Ovarian Tumors Conference for Young Investigators which was presented in Tokyo 2015 prior to the 5th Ovarian Cancer Consensus Conference of the Gynecologic Cancer InterGroup (GCIG)
DNA methylation-based classification reveals difference between pediatric T-cell acute lymphoblastic leukemia and normal thymocytes
Coordinate control of cell cycle regulatory genes in zebrafish development tested by cyclin D1 knockdown with morpholino phosphorodiamidates and hydroxyprolyl-phosphono peptide nucleic acids
During early zebrafish (Danio rerio) development zygotic transcription does not begin until the mid-blastula transition (MBT) ∼3 h after fertilization. MBT demarcates transition from synchronous short cell cycles of S and M phases exclusively to full cycles encompassing G(1) and G(2) phases. Transcriptional profiling and RT–PCR analyses during these phases enabled us to determine that this shift corresponds to decreased transcript levels of S/M phase cell cycle control genes (e.g. ccna2, ccnb1, ccnb2 and ccne) and increased transcript levels of ccnd1, encoding cyclin D1, and orthologs of p21 (p21-like) and retinoblastoma (Rb-like 1). To investigate the regulation of this process further, the translation of ccnd1 mRNA, a G(1)/S checkpoint control element, was impaired by microinjection of ccnd1-specific morpholino phosphorodiamidate (MO) 20mer or hydroxyprolyl-phosphono peptide nucleic acid (HypNA-pPNA) 16mer antisense oligonucleotides. The resulting downregulation of cyclin D1 protein resulted in microophthalmia and microcephaly, but not lethality. The phenotypes were not seen with 3-mismatch MO 20mers or 1-mismatch HypNA-pPNA 16mers, and were rescued by an exogenous ccnd1 mRNA construct with five mismatches. Collectively, these results indicate that transcription of key molecular determinants of asynchronous cell cycle control in zebrafish embryos commences at MBT and that the reduction of cyclin D1 expression compromises zebrafish eye and head development
Geographical distribution of hepatitis C virus genotypes in blood donors:an international collaborative survey
The frequency of infection with the six classified major genotypes of hepatitis C virus (HCV) was investigated in 447 infected volunteer blood donors from the following nine countries: Scotland, Finland, The Netherlands, Hungary, Australia, Egypt, Japan, Hong Kong, and Taiwan. Viral sequences in plasma from blood donors infected with HCV were amplified in the 5'-noncoding region and were typed by restriction fragment length polymorphism analysis. Electrophoresis of DNA fragments produced by cleavage with HaeIII-RsaI and ScrFI-HinfI allowed HCV types 1 (or 5), 2, 3, 4, and 6 to be identified. Further analysis with MvaI-HinfI allowed sequences of the type 5 genotype to be distinguished from sequences of type 1 genotype. Types 1, 2, and 3 accounted for almost all infections in donors from Scotland, Finland, The Netherlands, and Australia. Types 2 and 3 were not found in the eastern European country (Hungary), where all but one of the donors were infected with type 1. Donors from Japan and Taiwan were infected only with type 1 or 2, while types 1, 2, and 6 were found in those from Hong Kong. HCV infection among Egyptians was almost always by type 4. Donors infected with HCV type 1 showed broad serological reactivity with all four antigens of the second generation Chiron RIBA-2 assay (Chiron Corporation, Emeryville, Calif.), while infection with divergent HCV genotypes elicited antibodies mainly reactive to c22-3 and c33c. Reactivities with antibodies 5-1-1 and c100-3 were infrequent and were generally weak, irrespective of the geographical origin of the donor. Because the envelope region of HCV is even more variable than the NS-4 region, it is likely that vaccines based on these proteins need to be multivalent and perhaps specifically adapted for different geographical regions.link_to_subscribed_fulltex
Social Transmission of Avoidance Behavior under Situational Change in Learned and Unlearned Rats
BACKGROUND: Rats receive information from other conspecifics by observation or other types of social interaction. Such social interaction may contribute to the effective adaptation to changes of environment such as situational switching. Learning to avoid dangerous places or objects rapidly occurs with even a single conditioning session, and the conditioned memory tends to be sustained over long periods. The avoidance is important for adaptation, but the details of the conditions under which the social transmission of avoidance is formed are unknown. We demonstrate that the previous experience of avoidance learning is important for the formation of behaviors for social transmission of avoidance and that the experienced rats adapt to a change of situation determined by the presence or absence of aversive stimuli. We systematically investigated social influence on avoidance behavior using a passive avoidance test in a light/dark two-compartment apparatus. METHODOLOGY/PRINCIPAL FINDINGS: Rats were divided into two groups, one receiving foot shocks and another with no aversive experience in a dark compartment. Experienced and inexperienced rats were further divided into subjects and partners. In Experiment 1, each subject experienced (1) interaction with an experienced partner, (2) interaction with an inexperienced partner, or (3) no interaction. In Experiment 2, each subject experienced interaction with a partner that received a shock. The entering latency to a light compartment was measured. The avoidance behavior of experienced rats was inhibited by interaction with inexperienced or experienced partners in a safely-changed situation. The avoidance of experienced rats was reinstated in a dangerously-changed situation by interaction with shocked rats. In contrast, the inexperienced rats were not affected by any social circumstances. CONCLUSIONS/SIGNIFICANCE: These results suggest that transmitted information among rats can be updated under a situational change and that the previous experience is crucial for social enhancement and inhibition of avoidance behavior in rats
- …