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Orphan genes are located in a special evolutionary branch and have no significant sequence similarity with any other identified genes. Orphan genes are prevalent in every species, comparative genomics analyses found that all sequenced species contained a portion of orphan genes, and the number of orphan genes obtained by distinct screening conditions is different. Orphan genes are often associated with various stress responses, species-specific evolution and substance metabolism regulation. However, most of the orphan genes have not been well annotated or even have no recognizable functional domains, which brings some difficulties to the functional characterization of orphan genes. Compared with conserved genes, there is less research on orphan genes, which leads to the possibility that the importance of orphan genes may be "unrewarded". In this review, we summarize the origin and evolution of orphan genes, plant orphan gene screening and functions, and analyse the existing challenges and future research priorities and solutions, which provide theoretical basis for the study of orphan gene function and action mechanisms.
Assuntos
Evolução Molecular , Genes de Plantas , Especificidade da Espécie , Sequência de BasesRESUMO
Curcumin has been shown to significantly improve spatial memory impairment induced by HIV-1 gp120 V3 in rats, but the electrophysiological mechanism remains unknown. Using extracellular microelectrode recording techniques, this study confirmed that the gp120 V3 loop could suppress long-term potentiation in the rat hippocampal CA1 region and synaptic plasticity, and that curcumin could antagonize these inhibitory effects. Using a Fura-2/AM calcium ion probe, we found that curcumin resisted the effects of the gp120 V3 loop on hippocampal synaptosomes and decreased Ca(2+) concentration in synaptosomes. This effect of curcumin was identical to nimodipine, suggesting that curcumin improved the inhibitory effects of gp120 on synaptic plasticity, ameliorated damage caused to the central nervous system, and might be a potential neuroprotective drug.
RESUMO
Objective To evaluating the effectiveness of comprehensive measures to control the plague in epidemic areas in Longlin county Guangxi from 2001 to 2010.Methods Original epidemic places was deratised,indicative animals were investigated,and epidemic clues were searched.Cage trapping method was used to capture rat and rat body fleas were collected in the plague epidemic areas.The flea-carrying rates and flea index of rodents were calculated based on the number of fleas collected from caged rodents.The animals were then subjected to etiological and serological tests to determine the plague infection rate.Results A total of 1008 rats were captured and 571 fleas were collected from 2001 to 2010,of which Rattus Flavipestus accounted tor 81.65％(823/1008) and Xenopsylla Cheopis for 64.10％(366/571).The annual average rodents infected with flea and the index of flea were 23.02％ (177/769) and 0.74,respectively.The annual average density of rodents decreased from 3.99％ (859/21 508,before deratised) to 0.96％ (149/15 600,after deratised).The deratization rate was 75.94％.Conclusion The risk of a plague epidemic in Longlin county is reduced after continued comprehensive measures be taken to deal with the disease.
RESUMO
Objective To analyze the outcome of surveillance results on plague and to provide the evidences for the policy making in Longlin county Guangxi. Methods The epidemic data and the surveillance results of plague were analyzed and assessed with epidemiology methods in Longlin county Guangxi from 2000 to 2009, and the density of rodents, the rodents infected with flea, flea index and other indicators were calculated. Regional composition of the rats and fleas were analyzed. Results A totally of 4829 rats were captured and 4737 fleas were collected in the past 10 years, Rattus Flavipestus(81.92%,3956/4829) and Xenopsylla Cheopis (79.04%,3744/4737) were dominant species. The annual average density of rodents, the rodents infected with flea, index of flea were 3.30%(4829/146 206), 27.99%(1351/4827) and 0.98(4737/4827), respectively. A totally of 4792 rats were examined and 10 strains Yersinia Pestis were isolated. Indirect hemorrhagic assessed(IHA) was used to test the F1 antibody against plague in the blood serum of the rats and indicator animals, and 3 positive rats and 24 positive animals were found, respectively. Twenty seven natural villages in 3 towns had been involved in the plague. Conclusions The plague foci exists in Longlin county of Guangxi province. The plague foci in the areas have the same feature with the plague foci of Rattus Flavipectus. There is a potential risk for plague in this region, we should improve the quality of surveillance, increase indicator animals of the plague, and try to apply new surveillance method.
