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71.
Otero-Motta AP Ordóñez JL González-Celador R Rivas B Macías Mdel C Bullón A Abad Mdel M 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2011,119(3):204-215
Cervical cancer and its precursors low-grade squamous intraepithelial lesions (LSIL) and high-grade squamous intraepithelial lesions (HSIL) are associated with infection by human papillomavirus (HPV), in particular HPV 16 and 18. The distribution of the HPV genotype varies with the severity of cervical disease, age and the geographic location of the patients. We report the results of a population study carried out in a region of north-western (NW) Spain aimed at determining the prevalence of single and multiple infections by 35 types of HPV using low-density microarrays for 113 cases with negative for intraepithelial lesions or malignancies; 588 with atypical squamous cells of undetermined significance (ASCUS)/LSIL; 183 with HSIL; and seven cases of squamous cell carcinomas. Of the 891 patients analysed, 50.2% had single infections and 49.8% had multiple HPV infections. In women aged below 30 years, there was a predominance of multiple infections (p = 0.027). ASCUS/LSIL was associated with multiple and HSIL with single infections (p = 0.025). We observed significant increases in the percentage of infections due to a high-risk (HR) type of HPV when the severity of the cytological lesion increased (p = 0.001). No relationship was found between greater aggressiveness in the cytological diagnosis and a higher number of HPV types involved in multiple infections. The five most frequent genotypes were HPV 16 (26.3%), 53 (18.2%), 51 (17.3%), 6 (14.8%) and 66 (13.1%). The prevalence of HPV 16, 33 and 58 increased significantly from ACUS/LSIL to HSIL and the prevalence of HPV 51, 53 and 66 decreased. HPV 16 was the only genotype that showed a significant increase in prevalence when the severity of the cytological disease increased in single infections (p = 0.0001). The implementation of bivalent prophylactic vaccination could potentially lead to prevention in 32% of the population included in the study - in at least a quarter of patients with ACUS/LSIL (26.7%), and in half of HSIL (50.2%). 相似文献
72.
Paul JM Savelkoul Fabrizio De Mattia Yuedan Li Erik‐Jan Kamsteeg Irene BM Konings Peter van der Sluijs Peter MT Deen 《Human mutation》2009,30(10):E891-E903
Vasopressin regulates human water homeostasis by re‐distributing homotetrameric aquaporin‐2 (AQP2) water channels from intracellular vesicles to the apical membrane of renal principal cells, a process in which phosphorylation of AQP2 at S256 by cAMP‐dependent protein kinase A (PKA) is thought to be essential. Dominant nephrogenic diabetes insipidus (NDI), a disease in which the kidney is unable to concentrate urine in response to vasopressin, is caused by AQP2 gene mutations. Here, we investigated a reported patient case of dominant NDI caused by a novel p.R254Q mutation. Expressed in oocytes, AQP2‐p.R254Q appeared to be a functional water channel, but was impaired in its transport to the cell surface to the same degree as AQP2‐p.S256A, which mimics non‐phosphorylated AQP2. In polarized MDCK cells, AQP2‐p.R254Q was retained and was distributed similarly to that of unstimulated wt‐AQP2 or AQP2‐p.S256A. Upon co‐expression, AQP2‐p.R254Q interacted with, and retained wt‐AQP2 in intracellular vesicles. In contrast to wild‐type AQP2, forskolin did not increase AQP2‐p.R254Q phosphorylation at S256 or its translocation to the apical membrane. Mimicking constitutive phosphorylation in AQP2‐p.R254Q with the p.S256D mutation, however, rescued its apical membrane expression. These date indicate that a lack of S256 phosphorylation is the sole cause of dominant NDI here, and thereby, p.R254Q is a loss of function instead of a gain of function mutation in dominant NDI. © 2009 Wiley‐Liss, Inc. 相似文献
73.
Neus Martínez‐Abadías Talia L. Pankratz Yingli Wang Ethylin Wang Jabs Joan T. Richtsmeier 《Developmental dynamics》2013,242(1):80-94
BACKGROUND: The role of fibroblast growth factor and receptor (FGF/FGFR) signaling in bone development is well studied, partly because mutations in FGFRs cause human diseases of achondroplasia and FGFR‐related craniosynostosis syndromes including Crouzon syndrome. The FGFR2c C342Y mutation is a frequent cause of Crouzon syndrome, characterized by premature cranial vault suture closure, midfacial deficiency, and neurocranial dysmorphology. Here, using newborn Fgfr2cC342Y/+ Crouzon syndrome mice, we tested whether the phenotypic effects of this mutation go beyond the skeletal tissues of the skull, altering the development of other non‐skeletal head tissues including the brain, the eyes, the nasopharynx, and the inner ears. RESULTS: Quantitative analysis of 3D multimodal imaging (high‐resolution micro‐computed tomography and magnetic resonance microscopy) revealed local differences in skull morphology and coronal suture patency between Fgfr2cC342Y/+ mice and unaffected littermates, as well as changes in brain shape but not brain size, significant reductions in nasopharyngeal and eye volumes, and no difference in inner ear volume in Fgfr2cC342Y/+ mice. CONCLUSIONS: These findings provide an expanded catalogue of clinical phenotypes in Crouzon syndrome caused by aberrant FGF/FGFR signaling and evidence of the broad role for FGF/FGFR signaling in development and evolution of the vertebrate head. Developmental Dynamics 242:80–94, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
74.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献
75.
Kim YH; de Kretser DM; Temple-Smith PD; Hearn MT; McFarlane JR 《Molecular human reproduction》1997,3(4):307-313
Using mechanical and chemical dissection methods, fibrous sheath was
isolated both from normal ejaculated human spermatozoa and from rabbit
cauda epididymal spermatozoa. The same techniques did not produce a pure
preparation of fibrous sheath from ejaculated rabbit spermatozoa,
suggesting that further cross-linking and stabilization of sperm structures
occurs in response to components of the seminal plasma. The isolation
procedures were monitored by phase contrast microscopy and the purity of
the fibrous sheath was verified by electron microscopy. Sodium dodecyl
sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human
fibrous sheath revealed at least 14 protein bands of which the most
intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5
kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which
the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid
composition of the purified fibrous sheath from human and rabbit
spermatozoa was similar, being high in aspartic acid and/or asparagine and
glutamic acid and/or glutamine, serine, alanine, leucine, lysine and
glycine, but low in histidine, tyrosine and isoleucine. This composition is
similar to that reported for the rat and suggests that mammalian sperm tail
fibrous sheaths are composed of similar types of proteins, although there
are apparent differences in protein components between species.
相似文献
76.
Elastin point mutations cause an obstructive vascular disease, supravalvular aortic stenosis 总被引:7,自引:2,他引:7
Li DY; Toland AE; Boak BB; Atkinson DL; Ensing GJ; Morris CA; Keating MT 《Human molecular genetics》1997,6(7):1021-1028
Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular
disease that affects the aorta, carotid, coronary and pulmonary arteries.
Previous molecular genetic data have led to the hypothesis that SVAS
results from mutations in the elastin gene, ELN. In these studies, the
disease phenotype was linked to gross DNA rearrangements (35 and 85 kb
deletions and a translocation) in three SVAS families. However, gross
rearrangements of ELN have not been identified in most cases of autosomal
dominant SVAS. To define the spectrum of ELN mutations responsible for this
disorder, we refined the genomic structure of human ELN and used this
information in mutational analyses. ELN point mutations co-segregate with
the disease in four familial cases and are associated with SVAS in three
sporadic cases. Two of the mutations are nonsense, one is a single base
pair deletion and four are splice site mutations. In one sporadic case, the
mutation arose de novo. These data demonstrate that point mutations of ELN
cause autosomal dominant SVAS.
相似文献
77.
78.
Lucie MT Byrne-Davis Peter Salmon Katja Gravenhorst Tim OB Eden Bridget Young 《BMC medical research methodology》2010,10(1):101
Background
High accrual to clinical trials enables new treatment strategies to be tested rapidly, accurately and with generalisability. Ethical standards also must be high so that participation is voluntary and informed. However, this can be difficult to achieve in trials with complex designs and in those which are closely embedded in clinical practice. Optimal recruitment requires a balance of both ethical and accrual considerations. In the context of a trial of stratified treatments for children with acute lymphoblastic leukaemia (UKALL2003) we examined how recruitment looked to an observer and how it felt to the parents, to identify how doctors' communication could promote or inhibit optimal recruitment. 相似文献79.
Launay O Grabar S Gordien E Desaint C Jegou D Abad S Girard PM Bélarbi L Guérin C Dimet J Williams V Krivine A Salmon D Lortholary O Rey D;HEPAVAC Study Group 《Journal of acquired immune deficiency syndromes (1999)》2008,49(3):272-275
BACKGROUND: The immunogenicity of vaccines, including vaccine against hepatitis A virus (HAV), is impaired in patients with HIV infection, requiring revised immunization regimens. METHODS: We evaluated the immunological efficacy and safety of a 3-dose schedule of hepatitis A vaccine in HIV-infected adults. HAV-seronegative HIV-infected adults were randomized to receive either 3 doses of 1440 UI of hepatitis A vaccine (HAVRIX; GlaxoSmithKline, Marly le Roi, France) at weeks 0, 4, and 24 (46 patients) or 2 doses 24 weeks apart (49 patients). RESULTS: At week 28, seroconversion, defined as an anti-HAV antibody >or=20 mIU/mL, occurred in 82.6% and 69.4% of patients in the 3-dose and the 2-dose group, respectively (P = 0.13, intent-to-treat analysis, missing data = nonresponder), and in 88.4% and 72.3% of patients in the 3-dose and the 2-dose group, respectively (P = 0.06, observed analysis). Only 37.9% of patients experienced seroconversion after 1 vaccine dose (intent-to-treat analysis). Anti-HAV antibody geometric mean titers were 323 and 132 mIU/mL in the 3-dose group and 138 and 67 mIU/mL in the 2-dose group, respectively, 28 (P = 0.03) and 72 weeks (P = 0.05) after the first vaccine dose. There were no serious adverse events associated with the vaccine. Multivariate analysis showed no treatment group effect but indicated that absence of tobacco smoking (odds ratio = 2.92, 95% confidence interval: 1.07 to 7.97; P = 0.04) was an independent predictor of response to HAV vaccine. CONCLUSIONS: In HIV-infected adults, immunogenicity of hepatitis A vaccine is poor. Three doses of vaccine were safe and increased antibody titers. 相似文献
80.