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21.
A series of polyhydroxyl sulfides and triazoles was prepared by reacting allyl and propargyl d-mannose derivatives with selected thiols and azides in thiol–ene and Huisgen click reactions. Conformational analysis by NMR spectroscopy proved that the intrinsic rigidity and linear conformation of the mannose derived polyol backbone is retained in the final click products in solution. Single crystal X-ray structure determination of one of the compounds prepared further verified that the linear conformation of the polyol segment is also retained in the solid state. In addition, an improved method for direct Barbier-type propargylation of unprotected d-mannose is reported. The new reaction protocol, involving tin-mediated propargylation in an acetonitrile-water mixture, provides access to multigram quantities of the desired, valuable alkyne polyol without relying on protecting group manipulations or chromatographic purification.

An improved method for the propargylation of d-mannose and application of the rod-like polyol and its allylated analogue in click reactions is described.  相似文献   
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Journal of Neuro-Oncology - To estimate the maximum tolerated dose (MTD) and/or identify the recommended Phase II dose (RP2D) for combined INC280 and buparlisib in patients with recurrent...  相似文献   
25.
Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes.  相似文献   
26.
We studied the functional and structural consequences of two novel missense mutations in CYP21 found in women with hyperandrogenism. The women were predicted to carry mutations by hormonal evaluation, but did not display any of the genotypes commonly associated with congenital adrenal hyperplasia. In one woman the novel mutation V304M was found in homozygous form. After expression in COS-1 cells the mutated enzyme was found to have a residual activity of 46% for conversion of 17-hydroxyprogesterone and 26% for conversion of progesterone compared with the normal enzyme. The V304M variant thus represents the sixth known missense mutation associated with nonclassical disease. A normal degradation pattern for this mutant enzyme indicates that the missense mutation is of functional, rather than structural, importance. The other mutation, G375S, was detected in a young woman with signs of hyperandrogenism, in heterozygous form together with P453S, a mutation known to cause nonclassical congenital adrenal hyperplasia (her genotype was G375S+P453S/wild type). This novel variant almost completely abolished enzyme activity; conversion was 1.6% and 0.7% of normal for 17-hydroxyprogesterone and progesterone, respectively. These results underline the importance of genetic evaluation and counseling in hyperandrogenic women who are predicted to carry congenital adrenal hyperplasia-causing mutations by biochemical tests. It also supports the idea that the heterozygous carrier state for CYP21 mutations can be associated with symptoms of androgen excess in certain susceptible individuals.  相似文献   
27.

Background

The purpose of this study was to identify early features of lamin A/C gene mutation related dilated cardiomyopathy (DCM) with cardiovascular magnetic resonance (CMR). We characterise myocardial and functional findings in carriers of lamin A/C mutation to facilitate the recognition of these patients using this method. We also investigated the connection between myocardial fibrosis and conduction abnormalities.

Methods

Seventeen lamin A/C mutation carriers underwent CMR. Late gadolinium enhancement (LGE) and cine images were performed to evaluate myocardial fibrosis, regional wall motion, longitudinal myocardial function, global function and volumetry of both ventricles. The location, pattern and extent of enhancement in the left ventricle (LV) myocardium were visually estimated.

Results

Patients had LV myocardial fibrosis in 88% of cases. Segmental wall motion abnormalities correlated strongly with the degree of enhancement. Myocardial enhancement was associated with conduction abnormalities. Sixty-nine percent of our asymptomatic or mildly symptomatic patients showed mild ventricular dilatation, systolic failure or both in global ventricular analysis. Decreased longitudinal systolic LV function was observed in 53% of patients.

Conclusions

Cardiac conduction abnormalities, mildly dilated LV and depressed systolic dysfunction are common in DCM caused by a lamin A/C gene mutation. However, other cardiac diseases may produce similar symptoms. CMR is an accurate tool to determine the typical cardiac involvement in lamin A/C cardiomyopathy and may help to initiate early treatment in this malignant familiar form of DCM.  相似文献   
28.
Two brothers are reported suffering from X-linked Emery-Dreifuss muscular dystrophy caused by a 59bp deletion eliminating nucleotides 329-388 of the STA gene. Besides the typical findings for Emery-Dreifuss muscular dystrophy, both patients showed an unusual early onset of cardiac symptoms at age 6 and 9 years, respectively, coinciding with unusual high creatine kinase. A cardiological follow up showed worsening of the cardiac condition in the beginning of the second decade. The two boys described here belong to the very few Emery-Dreifuss muscular dystrophy patients with early onset of cardiac involvement and contribute to the variability of cardiac symptoms in Emery-Dreifuss muscular dystrophy.  相似文献   
29.
Linkage disequilibrium (LD) has been an efficient tool for fine mapping of monogenic disease genes in population isolates. Its usefulness for identification of predisposing loci for common, polygenic diseases has been challenged on the basis of anticipated allelic and locus heterogeneity. We compared the extent of LD among marker loci in Finnish subpopulations with divergent but well-characterized histories. One study sample represents the early settlement Finnish population, descended from two immigration events 4,000 and 2,000 years ago. The second sample represents the geographically large late settlement region, populated 15 generations ago by several small immigrant groups from the early settlement region. The third is a restricted regional subpopulation in northeastern Finland which was founded 12 generations ago by 39 immigrant families from the late settlement region. We genotyped 243 microsatellite markers and 68 single nucleotide polymorphisms (SNPs) on chromosomes 1q and 5q. The genealogy of the families from the early (n=16) and late settlements (n=54) and the isolated settlement (n=54) was studied in detail back to the 1800s. Microsatellite data revealed greater LD in the young, founder subpopulation than was seen in either of the older populations. Observed linkage disequilibrium correlated not only with physical distance between markers but also with the information content of the markers. Using biallelic SNP markers, significant LD could only be detected up to 0.1 cM. Our results demonstrate the complexity of the concept of 'detectable LD' and emphasize the importance of understanding population history when designing a strategy for disease gene mapping.  相似文献   
30.
Innate and adaptive immunity are the major defence mechanisms of higher organisms against inherent and environmental threats. Innate immunity is present already in unicellular organisms but evolution has added novel adaptive immune mechanisms to the defence armament. Interestingly, during aging, adaptive immunity significantly declines, a phenomenon called immunosenescence, whereas innate immunity seems to be activated which induces a characteristic pro-inflammatory profile. This process is called inflamm-aging. The recognition and signaling mechanisms involved in innate immunity have been conserved during evolution. The master regulator of the innate immunity is the NF-kB system, an ancient signaling pathway found in both insects and vertebrates. The NF-kB system is in the nodal point linking together the pathogenic assault signals and cellular danger signals and then organizing the cellular resistance. Recent studies have revealed that SIRT1 (Sir2 homolog) and FoxO (DAF-16), the key regulators of aging in budding yeast and Caenorhabditis elegans models, regulate the efficiency of NF-kB signaling and the level of inflammatory responses. We will review the role of innate immunity signaling in the aging process and examine the function of NF-kB system in the organization of defence mechanisms and in addition, its interactions with the protein products of several gerontogenes. Our conclusion is that NF-kB signaling seems to be the culprit of inflamm-aging, since this signaling system integrates the intracellular regulation of immune responses in both aging and age-related diseases.  相似文献   
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