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71.
Nicodemus KK Kolachana BS Vakkalanka R Straub RE Giegling I Egan MF Rujescu D Weinberger DR 《Human genetics》2007,120(6):889-906
Catechol-O-methyltransferase (COMT) regulates dopamine degradation and is located in a genomic region that is deleted in a syndrome
associated with psychosis, making it a promising candidate gene for schizophrenia. COMT also has been shown to influence prefrontal
cortex processing efficiency. Prefrontal processing dysfunction is a common finding in schizophrenia, and a background of
inefficient processing may modulate the effect of other candidate genes. Using the NIMH sibling study (SS), a non-independent
case-control set, and an independent German (G) case-control set, we performed conditional/unconditional logistic regression
to test for epistasis between SNPs in COMT (rs2097603, Val158Met (rs4680), rs165599) and polymorphisms in other schizophrenia
susceptibility genes. Evidence for interaction was evaluated using a likelihood ratio test (LRT) between nested models. SNPs
in RGS4, G72, GRM3, and DISC1 showed evidence for significant statistical epistasis with COMT. A striking result was found
in RGS4: three of five SNPs showed a significant increase in risk [LRT P-values: 90387 = 0.05 (SS); SNP4 = 0.02 (SS), 0.02 (G); SNP18 = 0.04 (SS), 0.008 (G)] in interaction with COMT; main effects
for RGS4 SNPs were null. Significant results for SNP4 and SNP18 were also found in the German study. We were able to detect
statistical interaction between COMT and polymorphisms in candidate genes for schizophrenia, many of which had no significant
main effect. In addition, we were able to replicate other studies, including allelic directionality. The use of epistatic
models may improve replication of psychiatric candidate gene studies. 相似文献
72.
The basidiomycete Phlebia centrifuga is a wood-decay fungus characteristic for unmanaged old-growth forests of spruce, a habitat that has become increasingly fragmented due to forest management. The aim of this study was to investigate the genetic population structures of P. centrifuga in both continuous and fragmented habitats, and estimate the potential impact of fragmentation on the genetic diversity of the fungus. Three hundred fifteen single spore isolates (representing 47 spore families and 33 single isolates) from eight populations across northern Europe (Russia, Finland, and Sweden) were screened with seven microsatellite markers and arbitrary primed polymerase chain reaction with the M13 minisatellite. The two molecular methods generally gave the same pattern for the genetic population structure. There were no significant differences between the observed and the expected heterozygosities, and the inbreeding coefficient (FIS) did not indicate any inbreeding. The fixation index (FST) revealed a general pattern with little to moderate genetic differentiation for the majority of populations, while the southernmost Swedish population Norra Kvill was the only one showing high differentiation from about half of the other populations. Swedish population Fiby with the shortest distance to the continuous habitat was moderately differentiated from most of the others and to the largest extent differed from geographically closest population of Norra Kvill. The results indicate that the fragmentation of old-growth forest in Russia and Finland is more recent than the fragmentation in Sweden, and the genetic population structures of P. centrifuga in northern Europe might be related to differences in forest landscape dynamics between the two areas. 相似文献
73.
Kaiser A Hammels I Gottwald A Nassar M Zaghloul MS Motaal BA Hauber J Hoerauf A 《Bioorganic & medicinal chemistry》2007,15(18):6200-6207
74.
Fusiogenic endogenous-retroviral syncytin-1 exerts anti-apoptotic functions in staurosporine-challenged CHO cells 总被引:1,自引:0,他引:1
Knerr I Schnare M Hermann K Kausler S Lehner M Vogler T Rascher W Meissner U 《Apoptosis : an international journal on programmed cell death》2007,12(1):37-43
Fusiogenic glycoprotein syncytin-1, expressed in human placenta, is a promising candidate for acquiring a basic knowledge
of placental syncytialization. However, its cellular mode of action is unidentified. We investigated whether syncytin-1 may
exert influence on apoptotic processes. Therefore, we incubated CHO cells after stable transfection with syncytin-1 (CHO-52)
in the presence or absence of staurosporine (STS), a kinase inhibitor well characterized to induce apoptosis. When testing
the phenotype of CHO-52 cells, we could demonstrate that the induction of apoptosis by STS was delayed over a period of up
to 24 h. Furthermore, the cell death rate was decreased by approx 75% following transfection of syncytin-1 in CHO-52 compared
to mock-treated cells. In detail, after 18h of incubation with 500 nM STS, 64 ± 2% of CHO-52 cells were viable compared to
16 ± 1% of CHO-mocks, after 24 h 43 ± 3% vs 5 ± 2%, respectively. CHO-52 cells exhibited a lower expression of active caspase
3 and anti-apoptotic Bcl-2 was found to be increased in CHO-52 cells at baseline and following STS treatment.
Our study provides first evidence that syncytin-1 serves anti-apoptotic function under certain conditions. A lessened activation
of caspase 3 and an increased expression of Bcl-2 are possible mechanisms. 相似文献
75.
Novel blocker of NFAT activation inhibits IL-6 production in human myometrial arteries and reduces vascular smooth muscle cell proliferation 总被引:1,自引:0,他引:1
76.
77.
Belle MD Pattison EF Cheunsuang O Stewart A Kramer I Sigrist M Arber S Morris R 《Genesis (New York, N.Y. : 2000)》2007,45(11):679-688
In this study, transgenic mice in which membrane-linked enhanced green fluorescent protein (mGFP) is expressed from the Thy1.2 promoter were used. In these mice, a subpopulation of small to medium sized DRG neurons double stained for IB4 but not for CGRP. Most of the peripheral terminals traversed the dermis and ramify within the epidermis and form superficial terminals. Within the spinal cord, these afferents terminated exclusively within the substantia gelatinosa (SG). A second fibre type in the skin also expressed mGFP, and formed club-shaped endings towards the bases of hairs. Injury to the sciatic nerve resulted in mGFP loss from the SG ipsilateral to the nerve injury, but also in the corresponding region contralaterally. Together, these findings reveal the specificity of connectivity of a defined subpopulation of DRG sensory neurons innervating the epidermis and this will facilitate analysis of their physiological functions. 相似文献
78.
79.
Raina K. Plowright Peggy Eby Peter J. Hudson Ina L. Smith David Westcott Wayne L. Bryden Deborah Middleton Peter A. Reid Rosemary A. McFarlane Gerardo Martin Gary M. Tabor Lee F. Skerratt Dale L. Anderson Gary Crameri David Quammen David Jordan Paul Freeman Lin-Fa Wang Jonathan H. Epstein Glenn A. Marsh Nina Y. Kung Hamish McCallum 《Proceedings. Biological sciences / The Royal Society》2015,282(1798)
Viruses that originate in bats may be the most notorious emerging zoonoses that spill over from wildlife into domestic animals and humans. Understanding how these infections filter through ecological systems to cause disease in humans is of profound importance to public health. Transmission of viruses from bats to humans requires a hierarchy of enabling conditions that connect the distribution of reservoir hosts, viral infection within these hosts, and exposure and susceptibility of recipient hosts. For many emerging bat viruses, spillover also requires viral shedding from bats, and survival of the virus in the environment. Focusing on Hendra virus, but also addressing Nipah virus, Ebola virus, Marburg virus and coronaviruses, we delineate this cross-species spillover dynamic from the within-host processes that drive virus excretion to land-use changes that increase interaction among species. We describe how land-use changes may affect co-occurrence and contact between bats and recipient hosts. Two hypotheses may explain temporal and spatial pulses of virus shedding in bat populations: episodic shedding from persistently infected bats or transient epidemics that occur as virus is transmitted among bat populations. Management of livestock also may affect the probability of exposure and disease. Interventions to decrease the probability of virus spillover can be implemented at multiple levels from targeting the reservoir host to managing recipient host exposure and susceptibility. 相似文献
80.