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21.
In an attempt to define the distinctive Wolf-Hirschhorn syndrome (WHS) phenotype, and to map its specific clinical manifestations, a total of eight patients carrying a 4p16.3 microdeletion were analyzed for their clinical phenotype and their respective genotypes. The extent of each individual deletion was established by fluorescence in situ hybridization, with a cosmid contig spanning the genomic region from MSX1 (distal half of 4p16.1) to the subtelomeric locus D4S3359. The deletions were 1.9-3.5 Mb, and all were terminal. All the patients presented with a mild phenotype, in which major malformations were usually absent. It is worth noting that head circumference was normal for height in two patients (those with the smallest deletions [1.9 and 2.2 Mb]). The currently accepted WHS critical region (WHSCR) was fully preserved in the patient with the 1.9-Mb deletion, in spite of a typical WHS phenotype. The deletion in this patient spanned the chromosome region from D4S3327 (190 b4 cosmid clone included) to the telomere. From a clinical point of view, the distinctive WHS phenotype is defined by the presence of typical facial appearance, mental retardation, growth delay, congenital hypotonia, and seizures. These signs represent the minimal diagnostic criteria for WHS. This basic phenotype maps distal to the currently accepted WHSCR. Here, we propose a new critical region for WHS, and we refer to this region as "WHSCR-2." It falls within a 300-600-kb interval in 4p16.3, between the loci D4S3327 and D4S98-D4S168. Among the candidate genes already described for WHS, LETM1 (leucine zipper/EF-hand-containing transmembrane) is likely to be pathogenetically involved in seizures. On the basis of genotype-phenotype correlation analysis, dividing the WHS phenotype into two distinct clinical entities, a "classical" and a "mild" form, is recommended for the purpose of proper genetic counseling.  相似文献   
22.
The diversity of autoimmune responses poses a formidable challenge to the development of antigen-specific tolerizing therapy. We developed 'myelin proteome' microarrays to profile the evolution of autoantibody responses in experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis (MS). Increased diversity of autoantibody responses in acute EAE predicted a more severe clinical course. Chronic EAE was associated with previously undescribed extensive intra- and intermolecular epitope spreading of autoreactive B-cell responses. Array analysis of autoantigens targeted in acute EAE was used to guide the choice of autoantigen cDNAs to be incorporated into expression plasmids so as to generate tolerizing vaccines. Tolerizing DNA vaccines encoding a greater number of array-determined myelin targets proved superior in treating established EAE and reduced epitope spreading of autoreactive B-cell responses. Proteomic monitoring of autoantibody responses provides a useful approach to monitor autoimmune disease and to develop and tailor disease- and patient-specific tolerizing DNA vaccines.  相似文献   
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The duration of lactational amenorrhoea, and infant feeding patterns and behaviour, were investigated in a sample of 97 mother-infant pairs living in a poor urban area of Dhaka, Bangladesh. A seven-hour time allocation method was used to determine the number of breast-feeding bouts and their duration. The seven-hour observation period was conducted on five occasions: at birth, 1 month, 4 months, 8 months and either 10 or 11 months. The median duration of lactational amenorrhoea was determined to be 24.07 weeks using survival analysis. Mothers who breast-fed their babies for longer and more frequently had, on average, a longer period of lactational amenorrhoea. There was no relationship between sociodemographic characteristics of the mother and duration of lactational amenorrhoea, nor was there any significant relationship between maternal anthropometry and birth weight of the baby and duration of lactational amenorrhoea, but there was a tendency for women with lower body mass index to have longer durations. Using the Cox proportional hazards model, the best predictor of duration of lactational amenorrhoea was the mean of months 0 and 1 durations of breast-feeding, adjusted for the mean frequencies for those months. The introduction of weaning food was also an important predictor.  相似文献   
25.
Understanding the mechanisms by which cytochrome(s) P450 (CYP) discriminate good from poor substrates, and orient them for highly regio- and stereoselective oxidation, has considerable intrinsic and practical importance. Here we present results of a study of fatty acid hydroxylation by CYP2B1 in a reconstituted system and in microsomes from phenobarbital-pretreated rats. The results indicate that 2B1 prefers decanoic acid as the optimum fatty acid substrate (among C(8)-C(16)) and that it hydroxylates all positions five or more methylene groups distant from the carboxylate carbon. That hydroxylation does not occur at carbon atoms closer to the carboxyl group than the C(6) position suggests that these carbons may not reach the ferryl oxygen because the carboxyl group is anchored to a specific site at a fixed distance from the heme iron.  相似文献   
26.
During early postnatal alveolar formation, the lung tissue of rat pups undergoes a physiological remodeling involving apoptosis of distal lung cells. Exposure of neonatal rats to severe hyperoxia (≥95% O(2)) both arrests lung growth and results in increased lung cell apoptosis. In contrast, exposure to moderate hyperoxia (60% O(2)) for 14 days does not completely arrest lung cell proliferation and is associated with parenchymal thickening. On the basis of similarities in lung architecture observed following either exposure to 60% O(2), or pharmacological inhibition of physiological apoptosis, we hypothesized that exposure to 60% O(2) would result in an inhibition of physiological lung cell apoptosis. Consistent with this hypothesis, we observed that the parenchymal thickening induced by exposure to 60% O(2) was associated with decreased numbers of apoptotic cells, increased expressions of the antiapoptotic regulator Bcl-xL, and the putative antiapoptotic protein survivin, and decreased expressions of the proapoptotic cleaved caspases-3 and -7. In summary, exposure of the neonatal rat lung to moderate hyperoxia results in an inhibition of physiological apoptosis, which contributes to the parenchymal thickening observed in the resultant lung injury.  相似文献   
27.
Diabetes impacts approximately 200 million people worldwide, of whom approximately 10% are affected by type 1 diabetes (T1D). The application of genome-wide association studies (GWAS) has robustly revealed dozens of genetic contributors to the pathogenesis of T1D, with the most recent meta-analysis identifying in excess of 40 loci. To identify additional genetic loci for T1D susceptibility, we examined associations in the largest meta-analysis to date between the disease and ∼2.54 million SNPs in a combined cohort of 9,934 cases and 16,956 controls. Targeted follow-up of 53 SNPs in 1,120 affected trios uncovered three new loci associated with T1D that reached genome-wide significance. The most significantly associated SNP (rs539514, P = 5.66×10−11) resides in an intronic region of the LMO7 (LIM domain only 7) gene on 13q22. The second most significantly associated SNP (rs478222, P = 3.50×10−9) resides in an intronic region of the EFR3B (protein EFR3 homolog B) gene on 2p23; however, the region of linkage disequilibrium is approximately 800 kb and harbors additional multiple genes, including NCOA1, C2orf79, CENPO, ADCY3, DNAJC27, POMC, and DNMT3A. The third most significantly associated SNP (rs924043, P = 8.06×10−9) lies in an intergenic region on 6q27, where the region of association is approximately 900 kb and harbors multiple genes including WDR27, C6orf120, PHF10, TCTE3, C6orf208, LOC154449, DLL1, FAM120B, PSMB1, TBP, and PCD2. These latest associated regions add to the growing repertoire of gene networks predisposing to T1D.  相似文献   
28.
The basic genomic defect in Wolf–Hirschhorn syndrome (WHS), including isolated 4p deletions and various unbalanced de novo 4p;autosomal translocations and above all t(4p;8p), is heterogeneous. Olfactory receptor gene clusters (ORs) on 4p were demonstrated to mediate a group of WHS-associated t(4p;8p)dn translocations. The breakpoint of a 4-Mb isolated deletion was also recently reported to fall within the most distal OR. However, it is still unknown whether ORs mediate all 4p-autosomal translocations, or whether they are involved in the origin of isolated 4p deletions. Another unanswered question is whether a parental inversion polymorphism on 4p16 can act as predisposing factor in the origin of WHS-associated rearrangements. We investigated the involvement of the ORs in the origin of 73 WHS-associated rearrangements. No hotspots for rearrangements were detected. Breakpoints on 4p occurred within the proximal or the distal olfactory receptor gene cluster in 8 of 73 rearrangements (11%). These were five t(4p;8p) translocations, one t(4p;7p) translocation and two isolated terminal deletions. ORs were not involved in one additional t(4p;8p) translocation, in a total of nine different 4p;autosomal translocations and in the majority of isolated deletions. The presence of a parental inversion polymorphism on 4p was investigated in 30 families in which the 4p rearrangements, all de novo, were tested for parental origin (7 were maternal and 23 paternal). It was detected only in the mothers of 3 t(4p;8p) cases. We conclude that WHS-associated chromosome changes are not usually mediated by low copy repeats. The 4p16.3 inversion polymorphism is not a risk factor for their origin. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Web Resources: Electronic Database Information: Online Mendelian Inheritance in Man (OMIM), (for WHS [MIM 194190]; Ensembl Human Map, ; UCSC, . An erratum to this article can be found at  相似文献   
29.
The fitness of a female's offspring depends cruicially on the traits, genetic and paternal, that the father contributes. As such, females may either have an interest in behaviorally choosing the highest‐quality male, or in reliably signaling their fertility status to males. Combining hormonal data on a female's ovulatory fertile window with a behavioral context, we suggest that captive female olive baboons (Papio h. anubis) provide fathers with reliable signals of their fertile period. One signal, the maximum anogenital swelling (AGA), typically coincided with a 4‐day fertile window of ovulation, which occurred 2–3 days prior to deturgescence. As expected from previous studies, AGA swelling indicated general attractiveness to males, and males attended to the relative attractiveness of females. Males approached and copulated with females significantly more often during the 4‐day window around ovulation, irrespective of the absolute swelling stage. The two adult males present in the group were both able to copulate with consistent partners as at least two cycling females were available in most months; the dominant male was more selective about the timing of his copulations close to ovulation during the maximal swelling phase. Females with ovulatory but nonconceptive cycles were less attractive to males, especially during their maximal AGA swelling phase. Am. J. Primatol. 71:529–538, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
30.
Early growth is of interest because it is susceptible to maternal effects and linked to fitness components for a range of species. Here we present anthropometric measurements on 23 infant olive baboons born into a captive colony in order to describe growth over the first 2 years of life, to explore maternal influences on growth, and to assess the impact of growth profiles on maternal reproduction. Six main findings emerged: 1) Infant growth rates in our colony were higher than those reported for wild populations but comparable to those observed for food-enhanced animals. 2) The ratio of infant mass to maternal mass was positively associated with reproductive parameters, such as duration of post-partum amenorrhea and interbirth interval. 3) Mothers resumed cycling and reconceived when their infants attained a relatively consistent threshold mass. 4) Infant mass-for-age was associated with maternal rank and, independently, with maternal mass such that females of high dominance rank and heavy females had relatively large infants at their resumption of cycling. 5) Low-ranking and lighter females had longer investment periods but smaller infants. They continued investment in infant through prolonged lactation until their infants reached a mass similar to that of infants of high-ranking/heavy mothers, suggesting that the lengthening of investment is essentially compensatory for slow early growth. 6) There was no relationship between infant growth and maternal activity budgets. Maternal physical and social factors, not energetics, contributed to differences among infants in growth trajectories, and infant growth temporally influenced successive reproductive events.  相似文献   
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