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991.
Jessica J. Lee Jonah B. Essers Subra Kugathasan Johanna C. Escher Guillaume Lettre Johannah L. Butler Michael C. Stephens Marco F. Ramoni Richard J. Grand Joel Hirschhorn 《Annals of human genetics》2010,74(6):489-497
The etiology of growth impairment in Crohn's disease (CD) has been inadequately explained by nutritional, hormonal, and/or disease‐related factors, suggesting that genetics may be an additional contributor. The aim of this cross‐sectional study was to investigate genetic variants associated with linear growth in pediatric‐onset CD. We genotyped 951 subjects (317 CD patient–parent trios) for 64 polymorphisms within 14 CD‐susceptibility and 23 stature‐associated loci. Patient height‐for‐age Z‐score < ?1.64 was used to dichotomize probands into growth‐impaired and nongrowth‐impaired groups. The transmission disequilibrium test (TDT) was used to study association to growth impairment. There was a significant association between growth impairment in CD (height‐for‐age Z‐score < ?1.64) and a stature‐related polymorphism in the dymeclin gene DYM (rs8099594) (OR = 3.2, CI [1.57–6.51], p = 0.0007). In addition, there was nominal over‐transmission of two CD‐susceptibility alleles, 10q21.1 intergenic region (rs10761659) and ATG16L1 (rs10210302), in growth‐impaired CD children (OR = 2.36, CI [1.26–4.41] p = 0.0056 and OR = 2.45, CI [1.22–4.95] p = 0.0094, respectively). Our data indicate that genetic influences due to stature‐associated and possibly CD risk alleles may predispose CD patients to alterations in linear growth. This is the first report of a link between a stature‐associated locus and growth impairment in CD. 相似文献
992.
W. Zac Stephens Megan Senecal Minhtu Nguyen Tatjana Piotrowski 《Developmental dynamics》2010,239(7):2066-2077
The distal region of neural retina (ciliary marginal zone [CMZ]) contains stem cells that produce non‐neural and neuronal progenitors. We provide a detailed gene expression analysis of the eyes of apc mutant zebrafish where the Wnt/β‐catenin pathway is constitutively active. Wnt/β‐catenin signaling leads to an expansion of the CMZ accompanied by a central shift of the retinal identity gene sox2 and the proneural gene atoh7. This suggests an important role for peripheral Wnt/β‐catenin signaling in regulating the expression and localization of neurogenic genes in the central retina. Retinal identity genes rx1 and vsx2, as well as meis1 and pax6a act upstream of Wnt/β‐catenin pathway activation. Peripheral cells that likely contain stem cells can be identified by the expression of follistatin, otx1, and axin2 and the lack of expression of myca and cyclinD1. Our results introduce the zebrafish apc mutation as a new model to study signaling pathways regulating the CMZ. Developmental Dynamics 239:2066–2077, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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Given that polycystic ovary syndrome (PCOS) is associated with oligo-ovulatory infertility and is an inherited trait, we hypothesized that the families of patients with PCOS are smaller than those of matched controls. However, our study of 106 white patients with PCOS, ages 18-45, and 53 healthy eumenorrheic nonhirsute white controls did not indicate a difference in family size between the groups; these results have important implications for the design of prospective studies of the heritability and genetics of PCOS. 相似文献
996.
Marie Lyons Joanna Stephens Joseph Wasson Nilantha DeZoysa Petros V. Vlastarakos 《European archives of oto-rhino-laryngology》2012,269(3):1041-1045
This study aimed to explore the current practice of performing high ear-piercing regarding consent protocols, and methods
of practice using questionnaire-based survey in Hertfordshire and North London. Recommendations for good clinical practice
are also made. 100 establishments performing ear piercing were identified. A 16-item questionnaire on techniques used, methods
of high-ear piercing, methods of sterilization, consent issues and aftercare was completed. Seventy-six establishments agreed
to participate. All practitioners prepared the skin before piercing. 58 (76%) used a needle for piercing, 11 (15%) used a
spring-loaded gun and seven (9%) used both. 97% of the practitioners obtained written consent before proceeding. 9 (12%) had
a lower age limit of 16 years and three (4%) of 18 years. 27 piercers (36%) provided an aftercare leaflet, 41 (54%) warned
the patients about risks of infection, 16 (21%) warned about cosmetic deformity and 1 (1%) specifically mentioned cauliflower
ear. Results indicated that high ear piercing is an invasive procedure with a significant risk of complications leading to
cosmetic deformity. Establishments should be required to counsel patients properly about the risks and potential complications
of the procedure. A code of practice should be drawn up with a minimum age for piercing, requirement for proper consent, excellent
hygiene and good information for postoperative care. 相似文献
997.
Shaaban AM Ball GR Brannan RA Cserni G Di Benedetto A Dent J Fulford L Honarpisheh H Jordan L Jones JL Kanthan R Maraqa L Litwiniuk M Mottolese M Pollock S Provenzano E Quinlan PR Reall G Shousha S Stephens M Verghese ET Walker RA Hanby AM Speirs V 《Breast cancer research and treatment》2012,133(3):949-958
Male breast cancer remains understudied despite evidence of rising incidence. Using a co-ordinated multi-centre approach, we present the first large scale biomarker study to define and compare hormone receptor profiles and survival between male and female invasive breast cancer. We defined and compared hormone receptor profiles and survival between 251 male and 263 female breast cancers matched for grade, age, and lymph node status. Tissue microarrays were immunostained for ERα, ERβ1, -2, -5, PR, PRA, PRB and AR, augmented by HER2, CK5/6, 14, 18 and 19 to assist typing. Hierarchical clustering determined differential nature of influences between genders. Luminal A was the most common phenotype in both sexes. Luminal B and HER2 were not seen in males. Basal phenotype was infrequent in both. No differences in overall survival at 5 or 10 years were observed between genders. Notably, AR-positive luminal A male breast cancer had improved overall survival over female breast cancer at 5 (P = 0.01, HR = 0.39, 95% CI = 0.26-0.87) but not 10 years (P = 0.29, HR = 0.75, 95% CI = 0.46-1.26) and both 5 (P = 0.04, HR = 0.37, 95% CI = 0.07-0.97) and 10 years (P = 0.04, HR = 0.43, 95% CI = 0.12-0.97) in the unselected group. Hierarchical clustering revealed common clusters between genders including total PR-PRA-PRB and ERβ1/2 clusters. A striking feature was the occurrence of ERα on distinct clusters between genders. In female breast cancer, ERα clustered with PR and its isoforms; in male breast cancer, ERα clustered with ERβ isoforms and AR. Our data supports the hypothesis that breast cancer is biologically different in males and females suggesting implications for clinical management. With the incidence of male breast cancer increasing this provides impetus for further study. 相似文献
998.
Michael Marotta Xiongfong Chen Ayako Inoshita Robert Stephens G Thomas Budd Joseph P Crowe Joanne Lyons Anna Kondratova Raymond Tubbs Hisashi Tanaka 《Breast cancer research : BCR》2012,14(6):R150
Introduction
Segmental duplications (low-copy repeats) are the recently duplicated genomic segments in the human genome that display nearly identical (> 90%) sequences and account for about 5% of euchromatic regions. In germline, duplicated segments mediate nonallelic homologous recombination and thus cause both non-disease-causing copy-number variants and genomic disorders. To what extent duplicated segments play a role in somatic DNA rearrangements in cancer remains elusive. Duplicated segments often cluster and form genomic blocks enriched with both direct and inverted repeats (complex genomic regions). Such complex regions could be fragile and play a mechanistic role in the amplification of the ERBB2 gene in breast tumors, because repeated sequences are known to initiate gene amplification in model systems.Methods
We conducted polymerase chain reaction (PCR)-based assays for primary breast tumors and analyzed publically available array-comparative genomic hybridization data to map a common copy-number breakpoint in ERBB2-amplified primary breast tumors. We further used molecular, bioinformatics, and population-genetics approaches to define duplication contents, structural variants, and haplotypes within the common breakpoint.Results
We found a large (> 300-kb) block of duplicated segments that was colocalized with a common-copy number breakpoint for ERBB2 amplification. The breakpoint that potentially initiated ERBB2 amplification localized in a region 1.5 megabases (Mb) on the telomeric side of ERBB2. The region is very complex, with extensive duplications of KRTAP genes, structural variants, and, as a result, a paucity of single-nucleotide polymorphism (SNP) markers. Duplicated segments are varied in size and degree of sequence homology, indicating that duplications have occurred recurrently during genome evolution.Conclusions
Amplification of the ERBB2 gene in breast tumors is potentially initiated by a complex region that has unusual genomic features and thus requires rigorous, labor-intensive investigation. The haplotypes we provide could be useful to identify the potential association between the complex region and ERBB2 amplification. 相似文献999.
1000.
Lee SS Aprecio RM Zhang W Arambula M Wilkins KB Stephens JA Kim JS Li Y 《Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995)》2008,29(5):302-4, 306, 308 passim
This article presents the results of a controlled clinical trial evaluating a new at-home treatment to improve gingival health. Designed for overnight application at the gingival margins and in the interproximal spaces, the product is a mucoadhesive gel containing 0.10% cetylpyridinium chloride (CPC) and 0.592% zinc gluconate (ZG). The authors assessed the efficacy and safety of the CPC/ZG gel in adults with low-to-moderate gingival and plaque index scores by comparing clinical and laboratory findings for subjects using the CPC/ZG gel with those for subjects using the control gel (0% CPC and 0.592% ZG). Clinical findings at 3 and 6 months showed statistically significant improvements in two of the three major indices of gingival health in the CPC/ZG group compared with the control group. The performance of the treatment gel was supported by results of microbial analyses of plaque samples. 相似文献