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51.
Olivia L. Conner Greg J. Siegle Ashley M. McFarland Jennifer S. Silk Cecile D. Ladouceur Ronald E. Dahl James A. Coan Neal D. Ryan 《PloS one》2012,7(12)
Close proximity to an attachment figure, such as a caregiver, has been shown to attenuate threat-related activity in limbic regions such as the hypothalamus in healthy individuals. We hypothesized that such features might be similarly attenuated by proximity during a potentially stressful situation in a clinically anxious population of youths. Confirmation of this hypothesis could support the role of attachment figures in the management of anxiety among children and adolescents. Three groups were analyzed: anxious children and adolescents who requested that their caregiver accompany them in the scanner room, anxious children and adolescents without their caregiver in the scanner room and healthy controls (each of N = 10). The groups were matched for age and, among the two anxious groups, for diagnosis (mean age 9.5). The children and adolescents were exposed to physical threat words during an fMRI assessment. Results indicate that activity in the hypothalamus, ventromedial, and ventrolateral prefrontal cortex were significantly reduced in anxious children and adolescents who requested that their caregiver accompany them in the scanner room compared to those without their caregiver in the scanner room. Mean activity in these regions in anxious children and adolescents with their caregiver in the scanner room was comparable to that of healthy controls. These data suggest links between social contact and neural mechanisms of emotional reactivity; specifically, presence of caregivers moderates the increase in anxiety seen with stressful stimuli. Capitalizing on the ability of anxious youths to manifest low levels of anxiety-like information processing in the presence of a caregiver could help in modeling adaptive function in behavioral treatments. 相似文献
52.
Kawamura K Yao K Shukaliak-Quandt JA Huh J Baig M Quigley L Ito N Necker A McFarland HF Muraro PA Martin R Ito K 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(8):5462-5472
Myelin basic protein (MBP)-specific T cells are thought to play a role in the development of multiple sclerosis. MBP residues 111-129 compose an immunodominant epitope cluster restricted by HLA-DRB1*0401. The sequence of residues 111-129 of MBP (MBP(111-129)) differs in humans (MBP122:Arg) and mice (MBP122:Lys) at aa 122. We previously found that approximately 50% of human MBP(111-129) (MBP122:Arg)-specific T cell clones, including MS2-3C8 can proliferate in response to mouse MBP(111-129) (MBP122:Lys). However, the other half of T cell clones, including HD4-1C2, cannot proliferate in response to MBP(111-129) (MBP122:Lys). We found that MBP(111-129) (MBP122:Lys) is an antagonist for HD4-1C2 TCR, therefore, MS2-3C8 and HD4-1C2 TCRs are agonist- and antagonist-specific TCRs in mice, respectively. Therefore, we examined the development of HD4-1C2 TCR and MS2-3C8 TCR transgenic (Tg) T cells in the thymus and periphery. We found that dual TCR expression exclusively facilitates the development of MBP(111-129) TCR Tg T cells in the periphery of HD4-1C2 TCR/HLA-DRB1*0401 Tg mice although it is not required for their development in the thymus. We also found that MS2-3C8 TCR Tg CD8(+) T cells develop along with MS2-3C8 TCR Tg CD4(+) T cells, and that dual TCR expression was crucial for the development of MS2-3C8 TCR Tg CD4(+) and CD8(+) T cells in the thymus and periphery, respectively. These results suggest that thymic and peripheral development of MBP-specific T cells are different; however, dual TCR expression can facilitate their development. 相似文献
53.
Taylor DL Booth MG McFarland JW Herriott IC Lennon NJ Nusbaum C Marr TG 《Molecular ecology resources》2008,8(4):742-752
High throughput sequencing methods are widely used in analyses of microbial diversity, but are generally applied to small numbers of samples, which precludes characterization of patterns of microbial diversity across space and time. We have designed a primer-tagging approach that allows pooling and subsequent sorting of numerous samples, which is directed to amplification of a region spanning the nuclear ribosomal internal transcribed spacers and partial large subunit from fungi in environmental samples. To test the method for phylogenetic biases, we constructed a controlled mixture of four taxa representing the Chytridiomycota, Zygomycota, Ascomycota and Basidiomycota. Following cloning and colony restriction fragment length polymorphism analysis, we found no significant difference in representation in 19 of the 23 tested primers. We also generated a clone library from two soil DNA extracts using two primers for each extract and compared 456 clone sequences. Community diversity statistics and contingency table tests applied to counts of operational taxonomic units revealed that the two DNA extracts differed significantly, while the pairs of tagged primers from each extract were indistinguishable. Similar results were obtained using UniFrac phylogenetic comparisons. Together, these results suggest that the pig-tagged primers can be used to increase ecological inference in high throughput sequencing projects on fungi. 相似文献
54.
Milstein ML McFarland TP Marsh JD Cala SE 《The Journal of biological chemistry》2008,283(4):1929-1935
In junctional sarcoplasmic reticulum, binding to cardiac triadin-1 provides a mechanism by which the Ca(2+)-release channel/ryanodine receptor may link with calsequestrin to regulate Ca(2+) release. Calsequestrin and triadin-1 both contain N-linked glycans, but about half of triadin-1 in the heart remains unglycosylated. To investigate mechanisms for this incomplete glycosylation, we overexpressed triadin-1 as a series of glycoform variants in non-muscle cell lines and neonatal heart cells using plasmid and adenoviral vectors. We showed that the characteristic incomplete glycosylation stemmed from properties of the glycosylation sequence that are conserved among triadin splice variants, including the close proximity of Asn(75) to the sarcoplasmic reticulum inner membrane. Although triadin-1 appeared by SDS-PAGE analysis as a 35/40-kDa doublet in all cells, variations occurred in the relative levels of the two glycoforms depending on the cell type and whether overexpression involved a plasmid or adenoviral vector. Treatment of triadin-1 with the proteasome inhibitor MG-132 led to striking changes in the relative levels of triadin-1 that indicated active breakdown of unglycosylated, but not glycosylated, triadin-1. Besides substantial increases in the relative levels of unglycosylated triadin-1, proteasome inhibition led to an accumulation of two new modified forms of triadin-1 that were seen with triadin-1 only when it is not glycosylated on Asn(75). Effects of tunicamycin and endoglycosidase H confirmed that these novel isoforms represent two alternative N-linked glycosylation sites, indicating that an alternative topology occurs infrequently leading to yet other glycoforms with short half-lives. 相似文献
55.
S Iu Kliushnik L M Selimova LM V M Za?des 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1990,(6):23-30
The optimum conditions for using the method of radioimmunoprecipitation (RIP) for the detection of human immunodeficiency virus (HIV) in serum samples have been established. Out of several available cell lines persistently infected with HIV, specially selected line 17 has been chosen. The characteristic feature of this is the high and stable (under the conditions of prolonged cultivation) accumulation of virus-specific proteins in infected cells. The optimum conditions for making the test and its evaluation have also been established. The data of literature on the advantages of the method of RIP over such traditional methods as the enzyme immunoassay and immunoblotting have been confirmed. Thus, the presence of specific antibodies in several serum samples registered as false negative has been established. The intertypical reactivity of two serotypes of the virus, HIV-1 and HIV-2, has been studied. Cross reactivity of antibodies with respect to the HIV gene gag, but not with respect to viral glycoproteids, has been established. Ideas on the expediency and prospects of using RIP for the serological control of HIV infection are presented. 相似文献
56.
57.
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Munychryia Walker and Gephyroneura Turner are separated from other Anthelidae as the Munychryiinae subfam. nov., using characters of both adult and immature stages. A new species, M. periclyta , is described from south-western Australia. 相似文献
Munychryia Walker and Gephyroneura Turner are separated from other Anthelidae as the Munychryiinae subfam. nov., using characters of both adult and immature stages. A new species, M. periclyta , is described from south-western Australia. 相似文献
58.
An unacceptably high incidence of gastro-oesophageal reflux was observed in a small series of patients with duodenal ulcer who had been treated by highly selective vagotomy. Possibly this is due to an altered angle of entry of the oesophagus into the stomach, and we now routinely narrow this angle at operation. 相似文献
59.
The resonance Raman spectrum has been recorded for two different binary complexes formed between 2-carboxy-2'-hydroxy-5'-sulfoformazylbenzene (zincon) and liver alcohol dehydrogenase. The shifts in the zincon spectrum upon complexation with enzyme in one complex are similar to those in model compounds containing azo or formazyl linkages upon complexation of these with zinc. The results are interpreted in terms of complexation of zincon to a zinc atom at the enzyme active site. Since zincon is a coenzyme competitive inhibitor, it is probably bound at or near the coenzyme binding site; the results of this study, therefore, are useful in understanding the chemistry of zinc at the enzyme active site. 相似文献
60.
P Echeverria B A Harrison C Tirapat A McFarland 《Applied and environmental microbiology》1983,46(1):32-36
The village of Ban Pong in northeastern Thailand was studied from January through December 1981 to determine the importance of flies as a source of enteric pathogens. The number of flies (predominantly Musca domestica) increased in kitchens and animal pens in the hot dry spring, when the incidence of diarrhea was highest in the village. Enterotoxigenic Escherichia coli, Shigella spp., non-O1 Vibrio cholerae, and Vibrio fluvalis were isolated from fly pools in yards (69%), animal pens (38%), bathrooms (35%), and kitchens (8%). Enterotoxigenic E. coli was isolated from one fly pool in May and from another in June, when the incidence of such infections was highest in the village. Flies often carry and presumably disseminate enteric pathogens in rural Thailand. 相似文献