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71.
72.
It is common to portray conservative and liberal Protestant denominations as “strong” and “weak” on the basis of indices such as church attendance. Alternatively, they can be regarded as qualitatively different cultural systems that coexist in a multiple-niche environment. We integrate these two perspectives with a study of American teenagers based on both one-time survey information and the experience sampling method (ESM), which records individual experience on a moment-by-moment basis. Conservative Protestant youth were found to be more satisfied, family-oriented, and sociable than liberal Protestant youth, but also more dependent on their social environment, which is reflected in a deterioration of their mood when they are alone. Liberal Protestant youth appear to have internalized values that remain constant whether in the presence or absence of others. We relate these results to the social scientific literature on liberalism and conservatism and to evolutionary theory as a framework for explaining cultural systems as adaptations to multiple-niche environments.
David Sloan WilsonEmail:
  相似文献   
73.
We sought to identify quantitative trait loci (QTLs) by genome‐wide linkage analysis for BMI and waist circumference (WC) exploring various strategies to address heterogeneity including covariate adjustments and complex models based on epistatic components of variance. Because cholesterol‐lowering drugs and diabetes medications may affect adiposity and risk of coronary heart disease, we excluded subjects medicated for hypercholesterolemia and hyperglycemia. The evidence of linkage increased on 2p25 (BMI: lod = 1.59 vs. 2.43, WC: lod = 1.32 vs. 2.26). Because environmental and/or genetic components could mask the effect of a specific locus, we investigated further whether a QTL could influence adiposity independently of lipid pathway and dietary habits. Strong evidence of linkage on 2p25 (BMI: lod = 4.31; WC: lod = 4.23) was found using Willet's dietary factors and lipid profile together with age and sex in adjustment. It suggests that lipid profile and dietary habits are confounding factors for detecting a 2p25 QTL for adiposity. Because evidence of linkage has been previously detected for BMI on 7q34 and 13q14 in National Heart, Lung, and Blood Institute Family Heart Study (NHLBI FHS), and for diabetes on 15q13, we investigated epistasis between chromosome 2 and these loci. Significant epistatic interactions were found between QTLs 2p25 and 7q34, 2q37 and 7q34, 2q31 and 13q14, and 2q31–q36 and 15q13. These results suggest multiple pathways and factors involving genetic and environmental effects influencing adiposity. By taking some of these known factors into account, we clarified our linkage evidence of a QTL on 2p25 influencing BMI and WC. The 2p25, 2q24–q31, and 2q36–q37 showed evidence of epistatic interaction with 7q34, 13q14, and 15q13.  相似文献   
74.
The accumulation of somatic mutations in mitochondrial DNA (mtDNA) induced by reactive oxygen species (ROS) is regarded as a major contributor to aging and age-related degenerative diseases. ROS have also been shown to facilitate the formation of certain advanced glycation end-products (AGEs) in proteins and DNA and N(2)-carboxyethyl-2'-deoxyguanosine (CEdG) has been identified as a major DNA-bound AGE. Therefore, the influence of mitochondrial ROS on the glycation of mtDNA was investigated in primary embryonic fibroblasts derived from mutant mice (Sod2(-/+)) deficient in the mitochondrial antioxidant enzyme manganese superoxide dismutase. In Sod2(-/+) fibroblasts vs wild-type fibroblasts, the CEdG content of mtDNA was increased from 1.90 ± 1.39 to 17.14 ± 6.60 pg/μg DNA (p<0.001). On the other hand, the CEdG content of nuclear DNA did not differ between Sod2(+/+) and Sod2(-/+) cells. Similarly, cytosolic proteins did not show any difference in advanced glycation end-products or protein carbonyl contents between Sod2(+/+) and Sod2(-/+). Taken together, the data suggest that mitochondrial oxidative stress specifically promotes glycation of mtDNA and does not affect nuclear DNA or cytosolic proteins. Because DNA glycation can change DNA integrity and gene functions, glycation of mtDNA may play an important role in the decline of mitochondrial functions.  相似文献   
75.
76.
To identify malaria antigens for vaccine development, we selected alpha-helical coiled coil domains of proteins predicted to be present in the parasite erythrocytic stage. The corresponding synthetic peptides are expected to mimic structurally "native" epitopes. Indeed the 95 chemically synthesized peptides were all specifically recognized by human immune sera, though at various prevalence. Peptide specific antibodies were obtained both by affinity-purification from malaria immune sera and by immunization of mice. These antibodies did not show significant cross reactions, i.e., they were specific for the original peptide, reacted with native parasite proteins in infected erythrocytes and several were active in inhibiting in vitro parasite growth. Circular dichroism studies indicated that the selected peptides assumed partial or high alpha-helical content. Thus, we demonstrate that the bioinformatics/chemical synthesis approach described here can lead to the rapid identification of molecules which target biologically active antibodies, thus identifying suitable vaccine candidates. This strategy can be, in principle, extended to vaccine discovery in a wide range of other pathogens.  相似文献   
77.

Background

Second-line therapy is frequently utilized for metastatic urothelial carcinoma, but there are limited data to guide this approach. While an assessment of overall survival based on registry data may not capture the impact of second- and third-line therapies on clinical outcome, this may be reflected in relative conditional survival (RCS).

Methods

Patients with stage IV urothelial carcinoma diagnosed from 1990–2010 were identified from the Surveillance, Epidemiology and End Results (SEER) dataset. The association of clinicopathologic variables with disease specific survival (DSS) was explored through univariate and multivariate analyses. DSS in subgroups divided by time period (1990–2000 v 2001–2010) was compared using the Kaplan-Meier method and log-rank test. One-year RCS at annual landmarks up to 5 years was compared in subgroups divided by time period.

Results

Of 261,987 patients diagnosed with urothelial carcinoma from 1990–2010, 3,110 patients met criteria for the current analysis. Characteristics of patients diagnosed between 1990 and 2000 (n = 810) and 2001 to 2010 (n = 2,300) were similar and there was no significant difference in DSS between the two groups. On multivariate analysis, older age (age ≥ 80) was associated with shorter DSS (HR 1.79, 95%CI 1.48–2.15), but no association was found between time period of diagnosis and outcome. One-year RCS improved substantially through successive annual landmarks up to 5 years, but no differences were seen in subgroups divided by time of diagnosis.

Conclusions

No difference in RCS was observed amongst patients with stage IV urothelial carcinoma diagnosed from 1990–2000 and 2001–2010. A lack of difference in RCS (more so than cumulative DSS) may reflect a lack of progress in salvage therapies for the disease.  相似文献   
78.
In this study, the role of Listeria monocytogenes ferritin was investigated. The fri gene encoding the ferritin was deleted and the phenotype of the mutant was analyzed demonstrating that ferritin is necessary for optimal growth in minimal medium in both presence and absence of iron, as well as after cold- and heat-shock. We also showed that ferritin provides protection against reactive oxygen species and is essential for full virulence of L. monocytogenes. A comparative proteomic analysis revealed an effect of the fri deletion on the levels of listeriolysin O and several stress proteins. Together, our study demonstrates that fri has multiple roles that contribute to Listeria virulence.  相似文献   
79.
Summary The tetracycline resistance transposon Tn10 was inserted into the E. coli chromosome near mglB550, a structural gene for the galactose-binding protein. P1 transductions established the position of these Tn10 insertions (zee-700, 701, 702::Tn10) close to the genes ptsF, fpk, cdd, mglB550, his, and gatA with 85%–95%, 85%, 36%, 20%–40%, 12%–15%, and 0.5% contransduction frequency. Three factor crosses revealed the relative sequence of the genes as: mglB550, zee-700::Tn10, ptsF, fpk, cdd, his. gatA was found to be 1.3% cotransducible with mglB550. Two Tn10 insertions near gatA were isolated and characterized. One, zef-704::Tn10, was 3% cotransducible with fpk, 8% with mglB550, and 42% with gatA. The other, zef-703::Tn10, was 98% cotransducible with gatA but not with mglB550 or fpk. Neither of these two Tn10 insertions was cotransducible with cdd. Four factor crosses revealed the sequence gatA, zef-704::Tn10, mglB550, fpk.Neither zee-700::Tn10 nor zef-703::Tn10 showed any (0/300) contransduction with either glpT or gyrA. The clockwise order of genes is then: his, cdd, fpk, ptsF, zee-700::Tn10, mglB550, zef-704::Tn10, gatA. With a fix-point for his at 44 min, fpk would be placed at 45 min and mglB550 at 45.5 min. During the course of this work we noticed that the cotransduction frequency between Tn10 insertions and nearby markers tended to increase when new P1 lysates were prepared from freshly reisolated strains. This may indicate loss of nonessential genes adjacent to Tn10 insertions. Using insertion zee-702::Tn10, we isolated deletions extending into an mgl gene other than mglB. Crosses between such a deletion mutant and an mglB550 mutant were done. The analysis of the periplasmic proteins of these as well as other transductants or recombinants involving the mglB550 or the mglB551 gene revealed the existence of strains synthesizing both the wild-type as well as the corresponding mutant protein. Strains containing both proteins exhibit either wild-type or mutant phenotype. These strains appeared unstable. Upon reisolation from purified stock cultures kept in glycerol at-20°C, colonies could be isolated that carried only mutant or wild-type protein.  相似文献   
80.
We describe an illusion in which a stranger's voice, when presented as the auditory concomitant of a participant's own speech, is perceived as a modified version of their own voice. When the congruence between utterance and feedback breaks down, the illusion is also broken. Compared to a baseline condition in which participants heard their own voice as feedback, hearing a stranger's voice induced robust changes in the fundamental frequency (F0) of their production. Moreover, the shift in F0 appears to be feedback dependent, since shift patterns depended reliably on the relationship between the participant's own F0 and the stranger-voice F0. The shift in F0 was evident both when the illusion was present and after it was broken, suggesting that auditory feedback from production may be used separately for self-recognition and for vocal motor control. Our findings indicate that self-recognition of voices, like other body attributes, is malleable and context dependent.  相似文献   
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