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101.
102.
A functional polymorphism in the regulatory region of the serotonin transporter gene (5-HTTLPR) is considered to be a plausible candidate gene for anxiety-related personality traits and for alcoholism. Empirical support for the association between 5-HTTLPR and psychological traits has been somewhat inconsistent; however, observations of the functional dominance of the low-activity s-allele over the l-allele have been more consistent. When studying the influence of particular genes on psychological traits, it seems useful also to assess more biological intermediate traits that may mediate the effects of those genes on the traits of interest. The present study examined relationships between 5-HTTLPR genotype, whole blood serotonin (5-HT) level, and platelet 5-HT binding in 150 Caucasian subjects from 50 biological families. Individuals with the s-allele had lower average platelet 5-HT binding availability than those with the l/l genotype (P<0.025). Whole blood 5-HT level was not associated with 5-HTTLPR genotype. In adult men, those with the s-allele had higher mean scores on the NEO-FFI personality trait of openness than did those with the l/l genotype (P=0.002). The effect was not statistically significant in women (P=0.42), although it was in the same direction. Our findings do not support an association of 5-HTTLPR genotype with alcoholism diagnosis, alcoholism subtype, or the personality trait of neuroticism. The results of this pilot study suggest that further work should examine the mediation of the genetic effects on personality traits by biochemical measures and their moderation by gender.  相似文献   
103.
Molecular Analysis of Fiji Disease Fijivirus Genome Segments 1 and 3   总被引:2,自引:0,他引:2  
Fiji disease fijivirus (FDV) genomic segments 1 (S1) and 3 (S3) were completely sequenced. FDV S1 comprised 4532nt and was predicted to encode a 170.6kDa protein. FDV S3 comprised 3623nt and was predicted to encode a 135.5kDa protein. The terminal sequences of S1 and S3 were 5 AAGUUUUU......CAGCUAGCGUC 3 and 5 AAGUUUUU......CAGCAGAUGUC 3, respectively, and located immediately adjacent to these sequences were 12bp imperfect inverted repeats. The predicted translation product of FDV S1 showed highest similarity to Rice black-streaked dwarf virus (RBSDV) S1 and is thought to encode the viral RNA-dependent RNA polymerase (RdRp). The predicted translation product of FDV S3 was found to be most similar to RBSDV S4 which is thought to encode the 'B-spike' protein. The FDV sequence contained an ATP/GTP binding motif and a leucine zipper motif, but these motifs were not found in the RBSDV sequence. Phylogenetic analysis based on the amino acid sequences of the RdRp of FDV S1 and other reoviruses revealed that the fijiviruses form a cluster close to the oryzaviruses. The RdRp sequences were grouped into genera that were consistent with the current reovirus classification scheme that is based on physico-chemical and biological properties.  相似文献   
104.
The relationship between odor identification and cognition has not been previously well characterized. The neuroanatomy of the olfactory system and the frequent finding of olfactory dysfunction in neurodegenerative diseases suggest a likely relationship between odor identification and memory, language, and executive functioning, though previous studies have often failed to demonstrate the expected relationship. The current study examined this relationship in across a continuum of ability levels (N=100). Strongest correlations were found between odor identification and language, most aspects of memory, and a measure of general cognitive functioning. Significant but more modest correlations were seen between odor identification and attention, motor, visuospatial, and executive functions. A regression analysis revealed language as the only significant predictor of olfactory performance. These findings suggest that odor identification is most closely associated with other measures of temporo-limbic functioning. The implications of these findings, particularly in consideration of the assessment of older adults, are discussed.  相似文献   
105.
Nonfunctioning islet cell tumors or pancreatic endocrine tumors are the most common type of malignant islet cell tumor. Although previously detected usually at an advanced stage because of mass effect, the early detection rate of small localized disease has been increasing. To date it has been difficult to predict the clinical behavior in localized regional nonfunctioning tumors. To investigate potential markers predicting malignancy and poor prognosis in nonfunctioning pancreatic endocrine tumors, we analyzed the expression of Ki-67, topoisomerase IIα (Topollα), and p27, as well as a variety of clinicopathologic parameters in 76 cases of nonfunctioning islet cell tumors (23 benign cases and 53 malignant cases). Ki-67, Topollα, and p27 labeling indices were significantly different between benign and malignant tumors. Expression of Ki-67, Topollα, and p27 were associated with survival in patients with a malignant tumor in a univariate setting. However, only p27 and Topollα were jointly associated with survival in multivariate analysis. Immunohistochemical staining for p27, Topollα, and Ki-67 can be helpful in the diagnosis of nonfunctioning pancreatic endocrine tumor. Analysis of p27 and Topollα may also have potential utility as prognostic factors for malignant tumors.  相似文献   
106.
A nine-test system using multiple-inoculation agar plates for biotyping of Escherichia coli is described. Testing of 959 strains resulted in 78 biotypes. On repeated testing, 96% of 182 strains had identical biotypes or differed by only one test. This system provides satisfactory differentiation among strains and is reproducible. Precise standardization of inoculum size is not required. Multiple inoculation allows time and cost-efficient testing of large numbers of strains.  相似文献   
107.
Activation of the coagulation cascade is commonly observed in the lungs of patients with both acute and chronic inflammatory and fibrotic lung disorders, as well as in animal models of these disorders. The aim of this study was to examine the contribution of the major thrombin receptor, proteinase-activated receptor-1 (PAR-1), during the acute inflammatory and chronic fibrotic phases of lung injury induced by intratracheal instillation of bleomycin in mice. Inflammatory cell recruitment and increases in bronchoalveolar lavage fluid (BALF) protein were attenuated by 56 +/- 10% (P < 0.05) and 53 +/- 12% (P < 0.05), respectively, in PAR-1-deficient (PAR-1-/-) mice compared with wild-type (WT) mice. PAR-1-/- mice were also protected from bleomycin-induced pulmonary fibrosis with total lung collagen accumulation reduced by 59 +/- 5% (P < 0.05). The protection afforded by PAR-1 deficiency was accompanied by significant reductions in pulmonary levels of the potent PAR-1-inducible proinflammatory and profibrotic mediators, monocyte chemoattractant protein-1 (MCP-1), transforming growth factor-beta-1 (TGF-beta1), and connective tissue growth factor/fibroblast-inducible secreted protein-12 (CTGF/FISP12). In addition, PAR-1 was highly expressed in inflammatory and fibroproliferative lesions in lung sections obtained from patients with fibrotic lung disease. These data show for the first time that PAR-1 signaling plays a key role in experimentally induced lung injury, and they further identify PAR-1 as one of the critical receptors involved in orchestrating the interplay between coagulation, inflammation, and remodeling in response to tissue injury.  相似文献   
108.
Cassell GD  Weitzman MD 《Virology》2004,327(2):206-214
Adeno-associated virus (AAV) replicates in the nucleus of infected cells, and therefore multiple nuclear import events are required for productive infection. We analyzed nuclear import of the viral Rep proteins and characterized a nuclear localization signal (NLS) in the C-terminus. We demonstrate that basic residues in this region constitute an NLS that is transferable and mediates interaction with the nuclear import receptor importin alpha in vitro. Mutant Rep proteins are predominantly cytoplasmic and are severely compromised for interactions with importin alpha, but retain their enzymatic functions in vitro. Interestingly, mutations of the NLS had significantly less effect on importin alpha interaction and replication in the context of Rep78 than when incorporated into the Rep68 protein. Together, our results demonstrate that a bipartite NLS exists in the shared part of Rep68 and Rep78, and suggest that an alternate entry mechanism may also contribute to nuclear localization of the Rep78 protein.  相似文献   
109.
Although it is known that systemic diseases such as diabetes result in impaired wound healing, the mechanism for this impairment is not understood. Because fibroblasts are essential for wound repair, we compared the in vitro behavior of fibroblasts cultured from diabetic, leptin receptor-deficient (db/db) mice with wild-type fibroblasts from mice of the same genetic background in processes important during tissue repair. Adult diabetic mouse fibroblast migration exhibited a 75% reduction in migration compared to normal fibroblasts (P < 0.001) and was not significantly stimulated by hypoxia (1% O(2)), whereas wild-type fibroblast migration was up-regulated nearly twofold in hypoxic conditions (P < 0.05). Diabetic fibroblasts produced twice the amount of pro-matrix metalloproteinase-9 as normal fibroblasts, as measured by both gelatin zymography and enzyme-linked immunosorbent assay (P < 0.05). Adult diabetic fibroblasts exhibited a sevenfold impairment in vascular endothelial growth factor (VEGF) production (4.5 +/- 1.3 pg/ml versus 34.8 +/- 3.3 pg/ml, P < 0.001) compared to wild-type fibroblasts. Moreover, wild-type fibroblast production of VEGF increased threefold in response to hypoxia, whereas diabetic fibroblast production of VEGF was not up-regulated in hypoxic conditions (P < 0.001). To address the question whether these differences resulted from chronic hyperglycemia or absence of the leptin receptor, fibroblasts were harvested from newborn db/db mice before the onset of diabetes (4 to 5 weeks old). These fibroblasts showed no impairments in VEGF production under basal or hypoxic conditions, confirming that the results from db/db fibroblasts in mature mice resulted from the diabetic state and were not because of alterations in the leptin-leptin receptor axis. Markers of cellular viability including proliferation and senescence were not significantly different between diabetic and wild-type fibroblasts. We conclude that, in vitro, diabetic fibroblasts show selective impairments in discrete cellular processes critical for tissue repair including cellular migration, VEGF production, and the response to hypoxia. The VEGF abnormalities developed concurrently with the onset of hyperglycemia and were not seen in normoglycemic, leptin receptor-deficient db/db mice. These observations support a role for fibroblast dysfunction in the impaired wound healing observed in human diabetics, and also suggest a mechanism for the poor clinical outcomes that occur after ischemic injury in diabetic patients.  相似文献   
110.
Alkylating agents are a structurally diverse group of compounds that cause a wide range of biological effects, including cell death, mutation and cancer. DNA damaged by these agents contains widely different amounts of 12 alkylated purines/pyrimidines and two phosphotriester isomers. The biological effects appear to be mediated predominantly by attack at the O(6) position of guanine. DNA extracted from various normal human tissues contains detectable levels of O(6)-alkylguanine, the source of which has not been defined. Given that, following DNA replication, this lesion cannot only generate point mutations but can also initiate mismatch repair-mediated DNA recombination and cell death, it seems worthwhile to consider the possible contribution of these events and cell killing to the aetiology of human cancer. There is increasing evidence that point mutations are not the only mechanism involved in malignant transformation by alkylating agents. Some cancer chemotherapeutic agents exploit the cytotoxic effects of O(6)-alkylguanine and an understanding of the processing of this lesion has allowed strategies to be developed that should increase the effectiveness of such agents.  相似文献   
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