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61.
María C. Lardone Altinay Marengo Alexis Parada-Bustamante Lucía Cifuentes Antonio Piottante Mauricio Ebensperger Raúl Valdevenito Andrea Castro 《Journal of assisted reproduction and genetics》2013,30(4):531-538
Purpose
To determine the prevalence of South Amerindian Y chromosome in Chilean patients with spermatogenic failure and their association with classical and/or AZFc-partial Y chromosome deletions.Methods
We studied 400 men, 218 with secretory azo/oligozoospermia (cases) and 182 controls (116 fertile and/or normozoospermic, and 66 azoospermic with normal spermatogenesis). After a complete testicular characterization (physical evaluation, hormonal and/or biopsy) peripheral blood was drawn to obtain DNA for Y chromosome microdeletions, AZFc-partial deletions and biallelic analysis by allele specific polymerase chain reaction (PCR) of the M3 (rs3894) single nucleotide polymorphism (SNP).Results
Classical AZF microdeletions were found in 23 cases (Y-microdeleted). AZFc-partial deletions were observed in 10 cases (6 “gr/gr”, 3 “b2/b3” and 1 “b1/b3”) and 4 controls (4 “gr/gr”). The AZFc-partial deletions were mainly associated with the absence of DAZ1/DAZ2 (64 %). No significant differences in the prevalence of AZFc-partial deletions were observed between cases and controls. We observed a significant higher proportion of the Q1a3a haplogroup in Y-microdeleted men compared to patients with spermatogenic failure without deletions and control men (P?<?0.01 and P?<?0.05, respectively by Bonferroni test). Among them, patients with AZFb deletions had an increased prevalence of the Q1a3a haplogroup compared to controls, cases without deletions and to those with complete or partial-AZFc deletions (P?<?0.01, Bonferroni test).Conclusions
The Q1a3a South Amerindian lineage seems to increase the susceptibility to non AZFc microdeletions. On the other hand, in Chilean population the AZFc-partial deletions (“gr/gr”, “b1/b3” and/or “b2/b3”) does not seem to predispose to severe spermatogenic impairment. 相似文献62.
José M Aldrighi Rute Loreto S Oliveira Élbio D'amico Tania RF Rocha Otávio E Gebara Giuseppe MC Rosano 《Gynecological endocrinology》2013,29(5):249-257
Objective.?The aim of the study was to investigate the impact of the climacterium (before and after menopause) on platelet activation.Background.?Platelet activation has been associated to the risk of cardiovascular disease. There is much speculation about the relationship between platelet function and sex steroids, due to peculiarities of platelet action between the genders, including concerns about the influence of low estradiol status in menopausal women.Methods.?By means of a cross-sectional study design, 37 female patients divided into two groups were compared. Group A consisted of ten women, mean age 43.9 years, in the premenopausal period, with normal estrogen levels; and Group B comprised 27 patients, mean age 53.0 years, who had all reached menopause. Platelet activation markers, namely P-selectin and glycoprotein IIb–IIIa complex (GPIIb–IIIa), were evaluated by flow cytometry with monoclonal antibodies. A binding index was calculated for both parameters (percentage of positive platelets?×?mean fluorescence of positive platelets). Also, thromboxane A2 was quantified by means of its main plasma metabolite, thromboxane B2, by enzyme immunoassay.Results.?P-selectin and GPIIb–IIIa expression results revealed lower platelet activation status after menopause, as there was a decrease in both the percentage of P-selectin?+? platelets and of GPIIb–IIIa mean fluorescence of positive platelets, lowering both binding indices. P-selectin binding index differed significantly between Group A (12.3?±?3, n?=?10) and Group B (6.2?±?2.9, n?=?27; mean?±?standard deviation (SD), p?<?0.001). GPIIb–IIIa binding index also differed significantly between both groups (Group A: 18.8?±?2.3, n?=?10 vs. Group B: 16.2?±?3.1, n?=?27; mean?±?SD, p?<?0.0018). Plasma concentration of thromboxane B2 was 1.07?±?0.5?pg/well before menopause (Group A, n?=?10) and 1.9?±?4.1?pg/well after menopause (Group B, n?=?27), not significantly different (mean?±?SD, baseline?×?therapy, p?=?0.85).Conclusions.?After the menopause, climacteric women – whose estradiol status is low – have a decreased activation platelet status compared with premenopausal women. Nevertheless, further studies on a larger sample are necessary for conclusive data regarding cardiovascular disease. 相似文献
63.
MC Bush S Patel RH Lapinski JL Stone 《The journal of maternal-fetal & neonatal medicine》2013,26(4):237-241
Objective: To determine whether inflammatory bowel disease (IBD) is associated with increased risk for adverse perinatal outcome.Methods: A case–control study of 116 singleton pregnancies with IBD compared to 56?398 singleton controls delivered between 1986 and 2001.Results: Patients with IBD were slightly older (32.8 vs. 30.6 years, p <?0.001), more likely to be Caucasian or Asian than Black or Latino (92% vs. 57%, p <?0.001) and have private health insurance (33% vs. 3%, p <?0.001). IBD was associated with an increased risk for labor induction (32% vs. 24%, p?=?0.002), chorioamnionitis (7% vs. 3%, p?=?0.04) and Cesarean section (32% vs. 22%, p?=?0.007), but there were no differences in neonatal outcomes. Subgroup analysis demonstrated an increased risk for low birth weight (LBW) in the ulcerative colitis group vs. the Crohn's disease group (19% vs. 0%, p?=?0.002). Patients with prior surgery for IBD had a lower incidence of LBW (0% vs. 12%, p?=?0.03). Flares during pregnancy were associated with an increased risk for preterm delivery (27% vs. 8%, p?=?0.02) and LBW (32% vs. 3%, p?=?0.003).Conclusion: IBD was an independent risk factor for Cesarean section but there was no increase in adverse perinatal outcome. Crohn's disease, prior IBD surgery and quiescent disease were associated with a lower risk for LBW. 相似文献
64.
Jun Aoki M.D. Richard P. Moser Jr. LTC MC USA Tuyethoa N. Vinh M.D. 《Skeletal radiology》1989,18(6):427-434
This study reviews the demographic, radiologic, and histologic characteristics of 13 cases of an important primary skeletal neoplasm, giant cell tumor of bone, occurring in an uncommon location, the scapula. that eight of 13 patients presented prior to 20 years of age contrasts significantly with the typical age distribution (between 20–40 years) encountered in giant cell tumors arising in long bones. As it does elsewhere in the skeleton, giant cell tumor of the scapula frequently demonstrates cystic and/or telangiectatic components on histologic examination. The radiologic appearances of giant cell tumor in the scapula and in more typical locations are similar and include: (1) well-defined (geographic) margins, occasionally with a delicate sclerotic rim, (2) prominent trabeculations, (3) expanded bone contour, (4) frequent extension to the subchondral plate, and (5) absence of internal mineralization. Tumor sites within the scapula included: coracoid process, acromion, and body (three cases each); glenoid (two cases); and superior and inferior angles (one case each).The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army, the Department of Defense, or the Uniformed Services University of the Health Sciences. 相似文献
65.
A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree. 相似文献
66.
Sequelae of acute renal infections: CT evaluation 总被引:1,自引:0,他引:1
Seventeen patients with upper urinary tract infection who underwent 51 computed tomographic studies (two to five per patient; mean, three) were retrospectively evaluated. Five to 10 days after the initial examination, there was little change in parenchymal abnormalities, but perirenal inflammation worsened and then subsided over 2-8 weeks. Enlargement of the affected kidney, present initially in 12 patients, persisted up to 6 weeks and resolved by 10-16 weeks. Abnormalities of parenchymal contrast material enhancement persisted for 1-2 months. New cortical scars appeared in six of 12 patients with an initially normal renal contour and in one of five patients who had scars initially. Three patients with a renal abscess developed a new calyceal diverticulum, presumably by rupture of the abscess into the collecting system. The present study shows that abnormalities of renal size and enhancement persist for weeks to months after clinical signs of infection resolve and that scarring in adults with urinary tract infection occurs more frequently than was previously realized. 相似文献
67.
Widespread Differential Maternal and Paternal Genome Effects on Fetal Bone Phenotype at Mid‐Gestation 下载免费PDF全文
Ruidong Xiang Alice MC Lee Tanja Eindorf Ali Javadmanesh Mani Ghanipoor‐Samami Madeleine Gugger Carolyn J Fitzsimmons Zbigniew A Kruk Wayne S Pitchford Alison J Leviton Dana A Thomsen Ian Beckman Gail I Anderson Brian M Burns David L Rutley Cory J Xian Stefan Hiendleder 《Journal of bone and mineral research》2014,29(11):2392-2404
Parent‐of‐origin–dependent (epi)genetic factors are important determinants of prenatal development that program adult phenotype. However, data on magnitude and specificity of maternal and paternal genome effects on fetal bone are lacking. We used an outbred bovine model to dissect and quantify effects of parental genomes, fetal sex, and nongenetic maternal effects on the fetal skeleton and analyzed phenotypic and molecular relationships between fetal muscle and bone. Analysis of 51 bone morphometric and weight parameters from 72 fetuses recovered at day 153 gestation (54% term) identified six principal components (PC1–6) that explained 80% of the variation in skeletal parameters. Parental genomes accounted for most of the variation in bone wet weight (PC1, 72.1%), limb ossification (PC2, 99.8%), flat bone size (PC4, 99.7%), and axial skeletal growth (PC5, 96.9%). Limb length showed lesser effects of parental genomes (PC3, 40.8%) and a significant nongenetic maternal effect (gestational weight gain, 29%). Fetal sex affected bone wet weight (PC1, p < 0.0001) and limb length (PC3, p < 0.05). Partitioning of variation explained by parental genomes revealed strong maternal genome effects on bone wet weight (74.1%, p < 0.0001) and axial skeletal growth (93.5%, p < 0.001), whereas paternal genome controlled limb ossification (95.1%, p < 0.0001). Histomorphometric data revealed strong maternal genome effects on growth plate height (98.6%, p < 0.0001) and trabecular thickness (85.5%, p < 0.0001) in distal femur. Parental genome effects on fetal bone were mirrored by maternal genome effects on fetal serum 25‐hydroxyvitamin D (96.9%, p < 0.001) and paternal genome effects on alkaline phosphatase (90.0%, p < 0.001) and their correlations with maternally controlled bone wet weight and paternally controlled limb ossification, respectively. Bone wet weight and flat bone size correlated positively with muscle weight (r = 0.84 and 0.77, p < 0.0001) and negatively with muscle H19 expression (r = –0.34 and –0.31, p < 0.01). Because imprinted maternally expressed H19 regulates growth factors by miRNA interference, this suggests muscle‐bone interaction via epigenetic factors. © 2014 American Society for Bone and Mineral Research. 相似文献
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