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High-frequency microsatellite haplotypes of the male-specific Y-chromosome can signal past episodes of high reproductive success of particular men and their patrilineal descendants. Previously, two examples of such successful Y-lineages have been described in Asia, both associated with Altaic-speaking pastoral nomadic societies, and putatively linked to dynasties descending, respectively, from Genghis Khan and Giocangga. Here we surveyed a total of 5321 Y-chromosomes from 127 Asian populations, including novel Y-SNP and microsatellite data on 461 Central Asian males, to ask whether additional lineage expansions could be identified. Based on the most frequent eight-microsatellite haplotypes, we objectively defined 11 descent clusters (DCs), each within a specific haplogroup, that represent likely past instances of high male reproductive success, including the two previously identified cases. Analysis of the geographical patterns and ages of these DCs and their associated cultural characteristics showed that the most successful lineages are found both among sedentary agriculturalists and pastoral nomads, and expanded between 2100 BCE and 1100 CE. However, those with recent origins in the historical period are almost exclusively found in Altaic-speaking pastoral nomadic populations, which may reflect a shift in political organisation in pastoralist economies and a greater ease of transmission of Y-chromosomes through time and space facilitated by the use of horses.  相似文献   
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Objective

To examine whether a Rasch analysis is sufficient to establish the construct validity of the Motor Function Measure (MFM) and discuss whether weighting the MFM item scores would improve the MFM construct validity.

Design

Observational cross-sectional multicenter study.

Setting

Twenty-three physical medicine departments, neurology departments, or reference centers for neuromuscular diseases.

Participants

Patients (N=911) aged 6 to 60 years with Charcot-Marie-Tooth disease (CMT), facioscapulohumeral dystrophy (FSHD), or myotonic dystrophy type 1 (DM1).

Interventions

None.

Main Outcome Measure(s)

Comparison of the goodness-of-fit of the confirmatory factor analysis (CFA) model vs that of a modified multidimensional Rasch model on MFM item scores in each considered disease.

Results

The CFA model showed good fit to the data and significantly better goodness of fit than the modified multidimensional Rasch model regardless of the disease (P<.001). Statistically significant differences in item standardized factor loadings were found between DM1, CMT, and FSHD in only 6 of 32 items (items 6, 27, 2, 7, 9 and 17).

Conclusions

For multidimensional scales designed to measure patient abilities in various diseases, a Rasch analysis might not be the most convenient, whereas a CFA is able to establish the scale construct validity and provide weights to adapt the item scores to a specific disease.  相似文献   
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Antisocial personality disorder (ASPD) often presents with highly impulsive, violent behavior, and pathological changes in the orbitofrontal cortex (OFC) and ventral striatum (VS) are implicated. Several compelling reasons support a relationship between low monoamine oxidase-A (MAO-A), an enzyme that regulates neurotransmitters, and ASPD. These include MAO-A knockout models in rodents evidencing impulsive aggression and positron emission tomography (PET) studies of healthy subjects reporting associations between low brain MAO-A levels and greater impulsivity or aggression. However, a fundamental gap in the literature is that it is unknown whether brain MAO-A levels are low in more severe, clinical disorders of impulsivity, such as ASPD. To address this issue, we applied [11C] harmine PET to measure MAO-A total distribution volume (MAO-A VT), an index of MAO-A density, in 18 male ASPD participants and 18 age- and sex-matched controls. OFC and VS MAO-A VT were lower in ASPD compared with controls (multivariate analysis of variance (MANOVA): F2,33=6.8, P=0.003; OFC and VS MAO-A VT each lower by 19%). Similar effects were observed in other brain regions: prefrontal cortex, anterior cingulate cortex, dorsal putamen, thalamus, hippocampus, and midbrain (MANOVA: F7,28=2.7, P=0.029). In ASPD, VS MAO-A VT was consistently negatively correlated with self-report and behavioral measures of impulsivity (r=−0.50 to −0.52, all P-values<0.05). This study is the first to demonstrate lower brain MAO-A levels in ASPD. Our results support an important extension of preclinical models of impulsive aggression into a human disorder marked by pathological aggression and impulsivity.  相似文献   
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OBJECTIVE: Surgery is the treatment of reference for early-stage esophageal cancer, but 5-year survival is only 20% to 25%. After complete resection (R0), survival is significantly longer than after incomplete resection, with microscopic (R1) or macroscopic (R2) penetration. The purpose of this work was to identify retrospectively the factors predictive of complete resection of operable esophageal cancers.PATIENTS AND METHODS: Between January 1982 and March 2001, 746 patients with esophageal cancer underwent curative surgery. R0 resection was performed in 585 patients (78.4%), R1 in 61 (8.2%) and R2 in 100 (13.4%). Univariate and multivariate analysis included 28 preoperative, clinical, tumor and therapeutic parameters.RESULTS: Multivariate analysis showed that factors predictive of complete resection R0 were: absence of any modification of the esophageal axis on the barium swallow (P=0.054), a partial or complete response to preoperative radio-chemotherapy (P=0.042), tumor height<10 cm (P=0.1) and tumor diameter<30 mm (P=0.01). Three groups of patients were identified from the 2 most significant variables. Group 1: no deviation of the axis on the barium swallow (n=501). Group 2: deviation of the axis on the barium swallow and partial or complete response to radiochemotherapy (n=91). Group 3: deviation of the axis on the barium swallow and no response to radiochemotherapy or no preoperative treatment (n=126). For the three groups, rate of R0 resection was 82.6%, 80.1% and 61.1% and 5-year actuarial survival 36%, 27% and 14%, respectively. These rates were significantly different between groups (P<10(- 4)) and two by two (P<0.04).CONCLUSION: Complete resection of esophageal cancer is predictable. After validation with an independent population the findings presented here could be used to establish stratification criteria for future therapeutic trials.  相似文献   
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