The inhibition effect of expressions of miR-221 and miR-222 on glioma and corresponding mechanism.

PURPOSE: This study was designed to investigate the expressions of genes miR-221 and miR-222 in glioma cells and elucidate the mechanism of the inhibition of expressions of miR-221 and miR-222 in glioma. METHODS: After being cultured, in vitro cells of U251 malignant glioma were divided into five groups, namely, blank control group, nonsense sequence ODN transfection group, AS-miR-221-ODN transfection group, AS-miR-222-ODN transfection group, AS-miR-221 ODN and AS-miR-222 0DN co-transfection group. RESULTS: The growth of the cells in AS-miR-221/222 group was significantly inhibited after transfection of 24 hours. Moreover, this inhibition degree became more apparent with prolonged time. The cell percentage in AS-miR-221/222 transfection group was 57.2 % in G0/G1 phase, 35.1 % in S phase, and 38.2 % in G2/M phase. The cell percentage in S phase was decreased. Cell cycle arrest was found in G0/G1 phase. Animal experiments showed that the glioma volume of AS-miR-221/222 treatment group was significantly different to that of the control group (p < 0.05). Furthermore, this difference gradually increased with time. It reached the maximum at the end of the observation period. In the U251 glioma specimens in AS-miR-221/222 treatment group, local glioma tissue developed necrosis foci. In addition, the nuclear size, color, heteromorphism, and new vessel number of these glioma tissues were decreased. CONCLUSION: There are a series of abnormal miRNA expressions in glioma. Among them, miR-221 and miR -222 are clustered miR s with elevated expressions. The over-expressions of miR-221 and miR-222 can be considered as new molecular tags for human glioma (Tab. 5, Fig. 4, Ref. 30).

Modes of hantavirus transmission in a population of Clethrionomys rufocanus bedfordiae inferred from mitochondrial and microsatellite DNA analyses.

To elucidate the mode of transmission of Puumala-related hantavirus in a population of gray red-backed voles, Clethrionomys rufocanus bedfordiae, in Hokkaido, Japan, we analyzed the kin structure and dispersal patterns of individual voles using microsatellite and mitochondrial DNA markers. Siblings or dam/offsprings was identified within the population based on the relatedness calculation with the microsatellite data. The pairwise relatedness values obtained could reveal kinship among all vole individuals within the population. Based on the assessment of kinship, we did not find a positive relationship between hantavirus transmission and close kinship. Males infected with the hantavirus carried a relatively uncommon mitochondrial haplotype. However, these infected males shared low relatedness values and were not considered closely related, i.e., they were not siblings or parent/offspring. These observations imply that hantavirus transmission in the vole population may not be related to close kinship but by random horizontal infection.

Serological analysis of hemorrhagic fever with renal syndrome (HFRS) patients in Far Eastern Russia and identification of the causative hantavirus genotype.

Hemorrhagic fever with renal syndrome (HFRS) is endemic in East Asia and Europe. The disease is caused by several viruses belonging to the genus Hantavirus, including the Hantaan virus (HTNV), Seoul virus (SEOV), Dobrava Belgrade virus (DOBV), and Puumala virus (PUUV). Recently, HTNV-related viruses, Amur (AMR) and Far East (FE) genotypes were identified as causative agents of HFRS in Far Eastern Russia. To investigate the epidemiology of HFRS and virus transmission, we collected sera from 17 acute and 32 convalescent patients who were clinically diagnosed with HFRS in the Khabarovsk region of Far Eastern Russia, and detected anti-hantavirus antibodies using an ELISA that can differentiate the infected virus serotype using truncated hantavirus nucleocapsid protein antigen. Sixteen of the 17 acute phase patients had antibodies to hantavirus, and all the positive sera had higher optical densities for HTNV-specific antigen than for SEOV-, DOBV-, or PUUV-specific antigens. The partial M segment of the viral genome was amplified from blood clots from three acute patients by PCR. The nucleotide sequences had closer identities to the FE genotype (>96%) than to the prototype HTNV (88 to 89%) or AMR genotype (81 to 83%). A phylogenetic analysis found that the virus sequences from the patients clustered with the FE type, and were distinct from the AMR type. Thirty-one of 32 convalescent patient sera had antibodies to HTNV-specific antigen. These data suggest that our ELISA system can detect HTNV-specific antibodies to the FE type, which may be responsible for most of the HFRS in Khabarovsk.