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91.
In Caucasian populations a single mutation, 35delG, accounts for the majority of GJB2 gene mediated hearing loss, with carrier frequencies estimated between 2-4%, possibly resulting from a founder effect rather than from a mutational hot spot. In Moroccan population, the 35delG mutation accounts for 90.8% of all GJB2 mutated alleles in deaf patients with a carrier frequency of 2.65%. The aim of this study was to evaluate whether the 35delG mutation has derived from a single origin in the Moroccan population. We enrolled 30 unrelated deaf patients homozygous for the 35delG mutation and 165 unrelated control individuals negative for this mutation, and genotyped three microsatellite markers flanking the GJB2 region: D13S141, D13S175 and D13S143. Data analysis revealed that the 35delG mutation is associated with particular alleles of these markers, with significant linkage disequilibrium for the 125 and 105 nucleotide long alleles of D13S141 and D13S175, and that a single specific haplotype accounts for 68% of the chromosomes carrying the 35delG mutation. The estimate age of 35delG mutation is 135 generations or approximately 2700 years old. Like in other Mediterranean populations, our results suggest that in the Moroccan population the 35delG mutation has derived from a single origin in a common founder process.  相似文献   
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We are developing tablet dosage forms for implantation directly into the subconjunctival space of the eye. The matrix metalloproteinase inhibitor, ilomastat, has previously been shown to be efficacious at suppressing scarring following glaucoma filtration surgery (GFS). We report on the physical characterisation of ilomastat which is being developed for ocular implantation. Since ilomastat is being considered for implantation it is necessary to examine its polymorphs and their influence on aspects of the in vitro drug release profile. X-ray powder diffraction identified two polymorphs of ilomastat from different commercial batches of the compound. Tablets were prepared from the two different polymorphs. Isothermal perfusion calorimetry was used to show that amorphous content is not increased during tablet formulation. The melting points of the two polymorphs are 188 and 208°C as determined by differential scanning calorimetry. Utilising single crystal X-ray diffraction, the structural conformations and packing arrangements of the different polymorphs were determined. The orthorhombic crystal crystallised as a monohydrate while the second monoclinic crystal form is non-solvated. Ilomastat tablets prepared from the two different solid forms exhibited similar drug release profiles in vitro under conditions mimicking the aqueous composition, volume and flow of the subconjunctival space after GFS. This suggests that a reproducible dose at each time point during release after implantation should be achievable in vivo with ilomastat tablets prepared from the two polymorphs identified.  相似文献   
94.
Acute oral administration of ethanol (3.2g/kg) to normal rats increased DOPAC levels and DOPA formation in the caudate nucleus but had no effect in the substantia nigra and frontal cortex and failed to modify dopamine (DA) levels in any of the above brain areas. Complete tolerance to the stimulant effect on DOPA formation developed after chronic ethanol administration (3.2g daily for 60 days). In chronically treated rats, 24 hrs after ethanol withdrawal, DA levels in the frontal cortex were 60% higher than in controls and were unchanged in the substantia nigra and caudate nucleus as were DOPAC levels in all areas studied. At this time, the administration of ethanol caused a long-lasting depletion of DA and a parallel increase of DOPAC levels in all areas analyzed. The results indicate that acute and chronic ethanol release DA stores but, in the acute condition, DA depletion is prevented by increased synthesis.  相似文献   
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Objective

The usefulness of the rapid‐induction techniques of hypnosis as an adjunctive weight‐loss treatment has not been defined. This randomized controlled trial evaluated whether self‐conditioning techniques (self‐hypnosis) added to lifestyle interventions contributed to weight loss (primary outcome), changes in metabolic and inflammatory variables, and quality of life (QoL) improvement (secondary outcomes) in severe obesity.

Methods

Individuals (with BMI = 35‐50 kg/m2) without organic or psychiatric comorbidity were randomly assigned to the intervention (= 60) or control arm (= 60). All received exercise and behavioral recommendations and individualized diets. The intervention consisted of three hypnosis sessions, during which self‐hypnosis was taught to increase self‐control before eating. Diet, exercise, satiety, QoL, anthropometric measurements, and blood variables were collected and measured at enrollment and at 1 year (trial end).

Results

A similar weight loss was observed in the intervention (?6.5 kg) and control (?5.6 kg) arms (β = ?0.45; 95% CI: ?3.78 to 2.88; = 0.79). However, habitual hypnosis users lost more weight (?9.6 kg; β = ?10.2; 95% CI: ?14.2 to ?6.18; P < 0.001) and greatly reduced their caloric intake (?682.5 kcal; β = ?643.6; 95% CI: ?1064.0 to ?223.2; P = 0.005) in linear regression models. At trial end, the intervention arm showed lower C‐reactive protein values (β = ?2.55; 95% CI: ?3.80 to ?1.31; P < 0.001), higher satiety (β = 19.2; 95% CI: 7.71‐30.6; P = 0.001), and better QoL (β = 0.09; 95% CI: 0.02‐0.16; P = 0.01).

Conclusions

Self‐hypnosis was not associated with differences in weight change but was associated with improved satiety, QoL, and inflammation. Indeed, habitual hypnosis users showed a greater weight loss.
  相似文献   
98.
Sequence-specific nuclear magnetic resonance (NMR) assignments have been determined for the peptide alphaS2-CN(2-20) containing the multiphosphorylated motif-8Ser(P)-Ser(P)-Ser(P)-Glu-Glu12- in the presence of molar excess Ca2+. The secondary structure of the peptide was characterized by sequential (i,i + 1), medium-range (i,i + 2/3/4) nOes and H alpha chemical shifts. Molecular modelling of the peptide based on these constraints suggests a nascent helix for residues Ser(P)9 to Glu12. The spectral data for alphaS2-CN(2-20) were compared with those of other casein phosphopeptides beta-CN(1-25) and alphaS1-CN(59-79) that also contain the multiphosphorylated motif. This comparison revealed a similar pattern of secondary amide chemical shifts in the multiphosphorylated motif. However, the patterns of medium-range nOe connectivities in the three peptides suggests they have distinctly different conformations in the presence of Ca2+ despite having a high degree of sequential similarity.  相似文献   
99.
Summary In the posterior part of the mid-gut epithelium in the lancelet, Branchiostoma lanceolatum, fine-grained cells occur. The appearance of the these cells is conspicuous with a basal and an apical swelling with small secretory granules. At the end of the secretion cycle the granular content is released into the gut lumen. The secretion product seems to consist of proteins and probably has an enzyme function. The restricted localization, the fine granulation, and the characteristic shape are features, that make these cells distinguishable from other secretory cells in the lancelet intestinal epithelium. A possible endocrine capacity of the cells is discussed.This work was supported by grant 2124-23 from the Swedish Natural Science Research Council and by grants from the Faculty of Science, University of Stockholm, Sweden.  相似文献   
100.
Emerging data have implicated a critical role for CD4 in the pathogenesis of systemic lupus erythematosus (SLE). This study was designed to delineate the contribution of CD4+ T cells in the pathogenesis of SLE disease. Forty-four patients (3 male: 41 female) and 20 healthy volunteers (4 male: 16 female) were included in the study. CD4+ lymphocytes analysis was done using three-color flow cytometry with antibodies against human-CD95, a prototype cell death receptor, and the chemokine receptor-7 (CCR7) after gating for lymphocytes based on the forward and side scatter. Serum levels of IL-6, IL-12, IL-17, TNF-α and IL-10 cytokines were assayed using ELISA. Disease activity was assessed using the SLE disease activity index (SLEDAI). Based on the expression of CCR7 and CD95, CD4+ lymphocytes were subdivided into three particular subsets; CD4+CD95+CCR7+ cells, CD4+CD95CCR7+ cells and CD4+CD95+CCR7 cells. Percentage of CD4+CD95+CCR7+ cell subset was significantly higher in patients with SLE with active disease (SLEDAI > 6) and inactive (SLEDAI < 6) as compared with controls (P = 0.005), and it showed a significant positive correlation with ANA titer (P = 0.01), and a negative correlation with WBCs count (P = 0.001). CD4+CD95+CCR7 cell subset was significantly higher in active SLE patients in comparison to patients with inactive disease and controls (P = 0.05, P = 0.005 respectively), and it correlates positively with SLEDAI, IL-6 and IL-17 levels (P = 0.001, 0.05, 0.01 respectively), and negatively with blood WBCs counts (P = 0.001). The third CD4+CD95CCR7+cell subset was found significantly lower in SLE patients compared with controls, and it was found negatively correlated with IL-10, IL-6, and IL-17. The results show that CD4+CD95+subset lacking expression of CCR7 is associated with cell mediated inflammatory response as manifested by its correlation with signs of inflammation, inflammatory cytokines and disease activity index. Whereas, CD4+CD95+CCR7+ correlate more with antibody immune responses as manifested by association with serum ANA. These data suggest disparate roles of these cell subsets in the pathophysiology of SLE. A better understanding of the characteristics of CD4 cell subsets may shed light on the pathogenesis of autoimmune diseases, particularly SLE.  相似文献   
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