38 research outputs found

    Testis and Antler Dysgenesis in Sitka Black-Tailed Deer on Kodiak Island, Alaska: Sequela of Environmental Endocrine Disruption?

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    It had been observed that many male Sitka black-tailed deer (Odocoileus hemionus sitkensis) on Kodiak Island, Alaska, had abnormal antlers, were cryptorchid, and presented no evidence of hypospadias. We sought to better understand the problem and investigated 171 male deer for phenotypic aberrations and 12 for detailed testicular histopathology. For the low-lying Aliulik Peninsula (AP), 61 of 94 deer were bilateral cryptorchids (BCOs); 70% of these had abnormal antlers. Elsewhere on the Kodiak Archipelago, only 5 of 65 deer were BCOs. All 11 abdominal testes examined had no spermatogenesis but contained abnormalities including carcinoma in situ–like cells, possible precursors of seminoma; Sertoli cell, Leydig cell, and stromal cell tumors; carcinoma and adenoma of rete testis; and microlithiasis or calcifications. Cysts also were evident within the excurrent ducts. Two of 10 scrotal testes contained similar abnormalities, although spermatogenesis was ongoing. We cannot rule out that these abnormalities are linked sequelae of a mutation(s) in a founder animal, followed by transmission over many years and causing high prevalence only on the AP. However, based on lesions observed, we hypothesize that it is more likely that this testis–antler dysgenesis resulted from continuing exposure of pregnant females to an estrogenic environmental agent(s), thereby transforming testicular cells, affecting development of primordial antler pedicles, and blocking transabdominal descent of fetal testes. A browse (e.g., kelp) favored by deer in this locale might carry the putative estrogenic agent(s)

    Thermosensitive Nanocables Prepared by Surface-Initiated Atom Transfer Radical Polymerization

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    Thermosensitive nanocables consisting of Au nanowire cores and poly(N-isopropylacrylamide) sheaths (denoted as Au/PNIPAAm) were synthesized by surface-initiated atom transfer radical polymerization (SI-ATRP). The formation of PNIPAAm sheath was verified by Fourier transform infrared (FTIR) and hydrogen nuclear magnetic resonance (1H NMR) spectroscopy. Transmission electron microscope (TEM) results confirmed the core/shell structure of nanohybrids. The thickness and density of PNIPAAm sheaths can be adjusted by controlling the amount of cross-linker during the polymerization. Signature temperature response was observed from Au/cross-linked-PNIPAAm nanocables. Such smart nanocables show immense potentials as building blocks for novel thermosensitive nanodevices in future

    Number of People Blind or Visually Impaired by Glaucoma Worldwide and in World Regions 1990 – 2010: A Meta-Analysis

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    Objective: To assess the number of individuals visually impaired or blind due to glaucoma and to examine regional differences and temporal changes in this parameter for the period from 1990 to 2012. Methods: As part of the Global Burden of Diseases (GBD) Study 2010, we performed a systematic literature review for the period from 1980 to 2012. We primarily identified 14,908 relevant manuscripts, out of which 243 high-quality, population-based studies remained after review by an expert panel that involved application of selection criteria that dwelt on population representativeness and clarity of visual acuity methods used. Sixty-six specified the proportion attributable to glaucoma. The software tool DisMod-MR (Disease Modeling–Metaregression) of the GBD was used to calculate fraction of vision impairment due to glaucoma. Results: In 2010, 2.1 million (95% Uncertainty Interval (UI):1.9,2.6) people were blind, and 4.2 (95% UI:3.7,5.8) million were visually impaired due to glaucoma. Glaucoma caused worldwide 6.6% (95% UI:5.9,7.9) of all blindness in 2010 and 2.2% (95% UI:2.0,2.8) of all moderate and severe visual impairment (MSVI). These figures were lower in regions with younger populations (10%). From 1990 to 2010, the number of blind or visually impaired due to glaucoma increased by 0.8 million (95%UI:0.7, 1.1) or 62% and by 2.3 million (95%UI:2.1,3.5) or 83%, respectively. Percentage of global blindness caused by glaucoma increased between 1990 and 2010 from 4.4% (4.0,5.1) to 6.6%. Age-standardized prevalence of glaucoma related blindness and MSVI did not differ markedly between world regions nor between women. Significance: By 2010, one out of 15 blind people was blind due to glaucoma, and one of 45 visually impaired people was visually impaired, highlighting the increasing global burden of glaucoma

    Cataract in patients with diabetes mellitus—incidence rates in the UK and risk factors

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    Aims: To analyze the risk of incident cataract (diagnosis or extraction) in patients with or without diabetes focusing on other comorbid conditions, antidiabetic drug use, and diabetes duration. Methods: The study population comprised newly diagnosed diabetes patients (≥40 years) from the UK-based Clinical Practice Research Datalink (CPRD) between 2000 and 2015, and a random sample of the general population matched for age, sex, general practice, and year of diabetes diagnosis. We assessed cataract incidence rates (IRs) and performed a nested case-control analysis in the diabetic cohort to assess potential risk factors for a cataract. Results: There were 56,510 diabetes patients included in the study. IRs of cataract were 20.4 (95% CI 19.8-20.9) per 1000 person-years (py) in patients with diabetes and 10.8 (95% CI 10.5-11.2) per 1000 py in the general population. IRs increased considerably around the age of 80 years and with a concomitant diagnosis of macular edema. The incidence rate ratio (IRR) was highest in patients of the age group of 45-54 years. In the nested case-control study, we identified 5800 patients with cataract. Risk of cataract increased with increasing diabetes duration (adj. OR 5.14, 95% CI 4.19-6.30 diabetes for ≥10 years vs. diabetes <2 years). Conclusions: According to our study, diabetes is associated with an approximately two-fold increased detection rate of cataract. The risk of cataract associated with diabetes is highest at younger ages. Patients with diabetic macular edema are at an increased risk for cataract as well as patients with long-standing diabetes
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