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101.
102.
Morphological integration refers to coordinated variation among traits that are closely related in development and/or function. Patterns of integration can offer important insight into the structural relationship between phenotypic units, providing a framework to address questions about phenotypic evolvability and constraints. Integrative features of the primate cranium have recently become a popular subject of study. However, an important question that still remains under-investigated is: what is the pattern of cranial shape integration among closely related hominoids? To address this question, we conducted a Procrustes-based geometric morphometrics study to quantify and analyze shape covariation patterns between different cranial regions in Homo, Pan, Gorilla and Pongo. A total of fifty-six 3D landmarks were collected on 407 adult individuals. We then sub-divided the landmarks corresponding to cranial units as outlined in the ‘functional matrix hypothesis.’ Sub-dividing the cranium in this manner allowed us to explore patterns of covariation between the face, basicranium and cranial vault, using the two-block partial least squares approach. Our results suggest that integrated shape changes in the hominoid cranium are complex, but that the overall pattern of integration is similar among human and non-human apes. Thus, despite having very distinct morphologies the way in which the face, basicranium and cranial vault covary is shared among these taxa. These results imply that the pattern of cranial integration among hominoids is conserved.  相似文献   
103.
Hormonal variation over the menstrual cycle alters women's preferences for phenotypic indicators of men's genetic or parental quality. Hormonal contraceptives suppress these shifts, inducing different mate preference patterns among users and non-users. This raises the possibility that women using oral contraception (OC) choose different partners than they would do otherwise but, to date, we know neither whether these laboratory-measured effects are sufficient to exert real-world consequences, nor what these consequences would be. Here, we test for differences in relationship quality and survival between women who were using or not using OC when they chose the partner who fathered their first child. Women who used OC scored lower on measures of sexual satisfaction and partner attraction, experienced increasing sexual dissatisfaction during the relationship, and were more likely to be the one to initiate an eventual separation if it occurred. However, the same women were more satisfied with their partner's paternal provision, and thus had longer relationships and were less likely to separate. These effects are congruent with evolutionary predictions based on cyclical preference shifts. Our results demonstrate that widespread use of hormonal contraception may contribute to relationship outcome, with implications for human reproductive behaviour, family cohesion and quality of life.  相似文献   
104.
105.

Introduction

Rheumatoid arthritis (RA) is associated with increased cardiovascular morbidity and mortality attributed to both classical risk factors and chronic inflammation. We assessed longitudinally the factors associated with new carotid plaques in nondiabetic RA patients and apparently healthy individuals.

Methods

In our present prospective observational study, carotid plaques were identified by ultrasonography at baseline and follow-up end, separated by an average of 3.6 ± 0.2 years, in 64 patients (mean age 59.2 ± 12.0 and disease duration at baseline 7.8 ± 6.2 years, 83% women, clinical and laboratory evaluation every 3 to 6 months). In a substudy, 35 of the patients were matched 1:1 for traditional cardiovascular risk factors with 'healthy' controls and were studied in parallel.

Results

New atherosclerotic plaques formed in 30% of patients (first plaque in 9%) who were significantly older than the remaining patients. Tobacco use, blood pressure, body mass index, average cumulative low-density lipoprotein, high-sensitivity C-reactive protein, erythrocyte sedimentation rate level, RA stage, functional class, disease duration and treatment modalities during follow-up did not differ significantly between subgroups after application of the Bonferroni correction. RA was in clinical remission, on average, for approximately 70% of the follow-up time and was not different between subgroups. Multivariate analysis including all the above parameters revealed that age (P = 0.006), smoking (P = 0.009) and duration of low-dose corticosteroid use (P = 0.016) associated independently with new plaque formation. RA patients displayed similar numbers of newly formed carotid plaques to the tightly matched for traditional cardiovascular risk factors 'healthy' controls, although more patients than controls had carotid plaques at baseline.

Conclusions

Formation of new atherosclerotic plaques in this small cohort of patients with well-controlled RA depended mainly on traditional cardiovascular risk factors and corticosteroid use, whereas an adverse effect of residual systemic inflammation was not readily detectable.  相似文献   
106.
Terrestrial slugs of the Island of Cyprus were recently studied in the framework of a study of the whole terrestrial malacofauna of the island. The present work was carried out in the Natura 2000 conservation areas of the island in 155 sampling sites over three years (2004-2007). Museum collections as well as literature references were included. In total six species are present in the Natura 2000 areas of the island, belonging to three families: Limacidae, Agriolimacidae and Milacidae. One of the species, Milax riedeli, is a new record for the island. The distribution of the species across the island and in the surrounding areas is discussed.  相似文献   
107.
The aim of this study was to investigate the changes induced by high tidal volume ventilation (HVTV) in pulmonary expression of micro-RNAs (miRNAs) and identify potential target genes and corresponding miRNA-gene networks. Using a real-time RT-PCR-based array in RNA samples from lungs of mice subjected to HVTV for 1 or 4 h and control mice, we identified 65 miRNAs whose expression changed more than twofold upon HVTV. An inflammatory and a TGF-β-signaling miRNA-gene network were identified by in silico pathway analysis being at highest statistical significance (P = 10(-43) and P = 10(-28), respectively). In the inflammatory network, IL-6 and SOCS-1, regulated by miRNAs let-7 and miR-155, respectively, appeared as central nodes. In TGF-β-signaling network, SMAD-4, regulated by miR-146, appeared as a central node. The contribution of miRNAs to the development of lung injury was evaluated in mice subjected to HVTV treated with a precursor or antagonist of miR-21, a miRNA highly upregulated by HVTV. Lung compliance was preserved only in mice treated with anti-miR-21 but not in mice treated with pre-miR-21 or negative-control miRNA. Both alveolar-arterial oxygen difference and protein levels in bronchoalveolar lavage were lower in mice treated with anti-miR-21 than in mice treated with pre-miR-21 or negative-control miRNA (D(A-a): 66 ± 27 vs. 131 ± 22, 144 ± 10 mmHg, respectively, P < 0.001; protein concentration: 1.1 ± 0.2 vs. 2.3 ± 1, 2.1 ± 0.4 mg/ml, respectively, P < 0.01). Our results show that HVTV induces changes in miRNA expression in mouse lungs. Modulation of miRNA expression can affect the development of HVTV-induced lung injury.  相似文献   
108.
Bovine tuberculosis is endemic in cattle herds in Great Britain, with a substantial economic impact. A reservoir of Mycobacterium bovis within the Eurasian badger (Meles meles) population is thought to have hindered disease control. Cattle herd incidents, termed breakdowns, that are either ‘prolonged’ (lasting ≥240 days) or ‘recurrent’ (with another breakdown within a specified time period) may be important foci for onward spread of infection. They drain veterinary resources and can be demoralising for farmers. Randomised Badger Culling Trial (RBCT) data were re-analysed to examine the effects of two culling strategies on breakdown prolongation and recurrence, during and after culling, using a Bayesian hierarchical model. Separate effect estimates were obtained for the ‘core’ trial areas (where culling occurred) and the ‘buffer’ zones (up to 2 km outside of the core areas). For breakdowns that started during the culling period, ‘reactive’ (localised) culling was associated with marginally increased odds of prolongation, with an odds ratio (OR) of 1.7 (95% credible interval [CI] 1.1–2.4) within the core areas. This effect was not present after the culling ceased. There was no notable effect of ‘proactive’ culling on prolongation. In contrast, reactive culling had no effect on breakdown recurrence, though there was evidence of a reduced risk of recurrence in proactive core areas during the culling period (ORs and 95% CIs: 0.82 (0.64–1.0) and 0.69 (0.54–0.86) for 24- and 36-month recurrence respectively). Again these effects were not present after the culling ceased. There seemed to be no effect of culling on breakdown prolongation or recurrence in the buffer zones. These results suggest that the RBCT badger culling strategies are unlikely to reduce either the prolongation or recurrence of breakdowns in the long term, and that reactive strategies (such as employed during the RBCT) are, if anything, likely to impact detrimentally on breakdown persistence.  相似文献   
109.
Posterior polymorphous corneal dystrophy (PPCD) is a rare autosomal dominant genetically heterogeneous disorder. Nineteen Czech PPCD pedigrees with 113 affected family members were identified, and 17 of these kindreds were genotyped for markers on chromosome 20p12.1- 20q12. Comparison of haplotypes in 81 affected members, 20 unaffected first degree relatives and 13 spouses, as well as 55 unrelated controls, supported the hypothesis of a shared ancestor in 12 families originating from one geographic location. In 38 affected individuals from nine of these pedigrees, a common haplotype was observed between D20S48 and D20S107 spanning approximately 23 Mb, demonstrating segregation of disease with the PPCD1 locus. This haplotype was not detected in 110 ethnically matched control chromosomes. Within the common founder haplotype, a core mini-haplotype was detected for D20S605, D20S182 and M189K2 in all 67 affected members from families 1–12, however alleles representing the core mini-haplotype were also detected in population matched controls. The most likely location of the responsible gene within the disease interval, and estimated mutational age, were inferred by linkage disequilibrium mapping (DMLE+2.3). The appearance of a disease-causing mutation was dated between 64–133 generations. The inferred ancestral locus carrying a PPCD1 disease-causing variant within the disease interval spans 60 Kb on 20p11.23, which contains a single known protein coding gene, ZNF133. However, direct sequence analysis of coding and untranslated exons did not reveal a potential pathogenic mutation. Microdeletion or duplication was also excluded by comparative genomic hybridization using a dense chromosome 20 specific array. Geographical origin, haplotype and statistical analysis suggest that in 14 unrelated families an as yet undiscovered mutation on 20p11.23 was inherited from a common ancestor. Prevalence of PPCD in the Czech Republic appears to be the highest worldwide and our data suggests that at least one other novel locus for PPCD also exists.  相似文献   
110.
Lysine (Lys) is an indispensable amino acid (AA) and generally the first limiting AA in vegetable protein sources in fish feeds. Inadequate dietary Lys availability may limit protein synthesis, accretion and growth of fish. This experiment aimed to further elucidate the role of Lys imbalance on growth by examining the myotomal muscle proteome of juvenile zebrafish (Danio rerio). Quadruplicate groups of 8 fish were fed either a low-Lys [Lys(-), 1.34?g?kg(-1)], medium/control (Lys, 2.47?g?kg(-1)) or high-Lys [Lys(+), 4.63?g?kg(-1)] diet. Fish growth was monitored from 33 to 49?days post-fertilization (dpf) and trunk myotomal muscle proteome of Lys(-) and Lys(+) treatments were screened by 2D-DIGE and MALDI ToF tandem mass spectrometry. Growth rate was negatively affected by diet Lys(-). Out of 527?±?11 (mean?±?S.E.M.) protein spots detected (~10-150?kDa and 4-7 pI value), 30 were over-expressed and 22 under-expressed in Lys(-) fish (|fold-change| >1.2, p value <0.05). Higher myosin light chains abundance and other myofibrillar proteins in Lys(-) fish pointed to increased sarcomeric degradation, indicating a higher protein turnover for supplying basal energy-saving metabolism rather than growth and muscle protein accretion. The Lys deficiency also possibly induced a higher feeding activity, reflected in the over-expression of beta enolase and mitochondrial ATP synthase. Contrarily, in the faster growing fish [Lys(+)], over-expression of apolipoprotein A-I, F-actin capping protein and Pdlim7 point to increased energy storage as fat and enhanced muscle growth, particularly by mosaic hyperplasia. Thus using an exploratory approach, this study pinpoints interesting candidates for further elucidating the role of dietary Lys on growth of juvenile fish.  相似文献   
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