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61.

Introduction

Phytoestrogens are a group of compounds found in plants that structurally resemble the hormone oestradiol, and thus have the potential to act as oestrogen agonists or antagonists. Their potential effects may alter the risk of breast cancer, but only a limited range of phytoestrogens has been examined in prospective cohort studies.

Methods

Serum and urine samples from 237 incident breast cancer cases and 952 control individuals (aged 45 to 75 years) in the European Prospective into Cancer-Norfolk cohort were analysed for seven phytoestrogens (daidzein, enterodiol, enterolactone, genistein, glycitein, o-desmethylangolensin, and equol) using liquid chromatography/mass spectrometry. Data on participants' diet, demographics, anthropometrics, and medical history were collected upon recruitment. All models were adjusted for weight, fat and energy intake, family history of breast cancer, social class, analytical batch, and factors related to oestrogen exposure.

Results

Urinary or serum phytoestrogens were not associated with protection from breast cancer in the European Prospective into Cancer-Norfolk cohort. Breast cancer risk was marginally increased with higher levels of total urinary isoflavones (odds ratio = 1.08 (95% confidence interval = 1.00 to 1.16), P = 0.055); among those with oestrogen receptor-positive tumours, the risk of breast cancer was increased with higher levels of urinary equol (odds ratio = 1.07 (95% confidence interval = 1.01 to 1.12), P = 0.013).

Conclusion

There was limited evidence of an association between phytoestrogen biomarkers and breast cancer risk in the present study. There was no indication of decreased likelihood of breast cancer with higher levels of phytoestrogen biomarkers, but the observation that some phytoestrogen biomarkers may be associated with greater risk of breast cancer warrants further study with greater statistical power.  相似文献   
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PURPOSE: CNTF is a neuroprotective agent for retinal degenerations that can cause reduced electroretinogram (ERG) amplitudes. The goal of the present study was to determine the effects of intraocular delivery of CNTF on normal rat visual function. METHODS: Full-field scotopic and photopic ERG amplitudes and spatial frequency thresholds of the optokinetic response (OKR) of adult Long-Evans rats were measured before and after intravitreous injection of CNTF or subretinal delivery of adenoassociated virus-vectored CNTF (AAV-CNTF) into one eye. Visual acuity was also measured by using the Visual Water Task in AAV-CNTF-injected animals. Multiunit luminance thresholds were recorded in the superior colliculus after CNTF injection, and the eyes were examined histologically. RESULTS: In eyes injected with a high dose of CNTF, ERG amplitudes and OKR thresholds measured through CNTF-injected eyes were decreased by 45% to 70% within 6 days after injection. ERG amplitudes had begun to recover by 21 days, whereas OKR thresholds only began to recover after 56 days. Neither OKR thresholds nor ERG amplitudes fully recovered until 90 to 100 days. When measured in the superior colliculus at 2 weeks after CNTF injection, luminance thresholds were elevated by 0.35 log units. In AAV-CNTF-injected eyes, OKR thresholds, and visual acuity were reduced by approximately 50% for at least 6 months, and scotopic and photopic ERG b-waves were reduced by 30% to 50%. Photoreceptor loss occurred in the injected regions in some of the eyes. By contrast, comparison of dose-response analysis with a dose-response study of light damage strongly suggests that therapeutic doses of CNTF exist that do not suppress ERG responses. CONCLUSIONS: Intraocular delivery of CNTF, which preserves photoreceptors in animal models of retinal degeneration, impairs visual function in normal rats at very high doses, but not at lower doses that still provide protection from constant light damage.  相似文献   
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Glucocorticoid suppressible hyperaldosteronism (GSH) is an uncommon form of dominantly inherited hypertension. Presentation with hypertension and complications such as stroke in early life are well recognised. The use of a simple genetic test carried out on blood or placenta facilitates the detection of infants and children with GSH before the development of hypertension, allowing prompt treatment of hypertension if it occurs, and an opportunity to study the effects of growth and environmental influences on the progression of the condition.  相似文献   
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A 35-year-old Asian Indian female previously diagnosed with bilateral anterior uveitis and on oral methotrexate developed bilateral anterior uveitis following first/second dose of coronavirus disease 2019 (COVID-19) vaccination. She had skipped her weekly dose of oral methotrexate following first dose of vaccination. Following the second dose, she reduced her oral methotrexate from 25 to 15 mg on her own, but did not stop like the previous occasion. She had extensive workup for her uveitis in the past with only positive severe acute respiratory syndrome coronavirus (SARS-CoV-2) antibodies. She developed unilateral anterior uveitis after she had COVID-19 in July 2022, which resolved with topical steroids and continuation of immunosuppression. This report illustrates that COVID-19 or its vaccination may presumably play a role in triggering the immune system and can cause recurrent ocular inflammation even in the absence of an extraocular inflammation.  相似文献   
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In previous studies we have found that monocytes produce soluble factors that stimulate human umbilical vein endothelial cells to produce granulocyte-macrophage colony-stimulating activity (CSA), burst- promoting activity (BPA), and megakaryocyte colony-stimulating activity (Meg-CSA) as well as factors that stimulate T lymphocytes and neonatal fibroblasts to produce CSA. To test the hypothesis that monocytes would similarly stimulate the production of hematopoietic growth factors by autologous bone marrow stromal cells, multiply-passaged adherent fibroblastoid cells derived from the bone marrow of normal volunteers were exposed to conditioned media prepared by incubating autologous peripheral blood monocytes in complete medium for three days. When conditioned media from stromal cells incubated in monocyte-conditioned medium were compared with those of stromal cells cultured in the absence of monocyte-conditioned medium, BPA was increased fourfold and CSA was increased more than 30-fold. We conclude that mononuclear phagocytes recruit stromal cells of the marrow to produce multilineage growth factors in vitro. We suggest that these monocyte-derived recruiting activities may play an important role in orchestration of hematopoietic growth factor production by cells of the marrow microenvironment.  相似文献   
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