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1.
Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen.  相似文献   
2.
The present narrative review examines the scientific evidence of the biological mechanisms that may link periodontitis and diabetes, as a source of comorbidity. Publications regarding periodontitis and diabetes, in human, animals, and in vitro were screened for their relevance. Periodontal microbiome studies indicate a possible association between altered glucose metabolism in prediabetes and diabetes and changes in the periodontal microbiome. Coinciding with this, hyperglycemia enhances expression of pathogen receptors, which enhance host response to the dysbiotic microbiome. Hyperglycemia also promotes pro-inflammatory response independently or via the advanced glycation end product/receptor for advanced glycation end product pathway. These processes excite cellular tissue destruction functions, which further enhance pro-inflammatory cytokines expression and alteration in the RANKL/osteoprotegerin ratio, promoting formation and activation of osteoclasts. The evidence supports the role of several pathogenic mechanisms in the path of true causal comorbidity between poorly controlled diabetes and periodontitis. However, further research is needed to better understand these mechanisms and to explore other mechanisms.  相似文献   
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Since the introduction of cART (combination antiretroviral therapy), HIV has evolved into a chronic disease such that it requires lifelong medical treatment to which patients must adhere. Communication with health care providers is pivotal in supporting patients to adapt to having HIV and adhering to treatment, in order to maintain health and quality of life. Previous research indicates that communication is optimal when it matches patient preferences for information exchange, relationship establishment, and involvement in treatment decisions. The aim of the present study is to explore HIV patient communication preferences as well as patient experiences with their providers (not) matching their preferences. A second aim is to explore provider beliefs about patient preferences and provider views on optimal communication. Data were collected through interviews with 28 patients and 11 providers from two academic hospitals. Results indicate that patient preferences reflect their cognitive, emotional, and practical needs such that patients look to increase their sense of control over their HIV. Patients aim to further increase their sense of control (by proxy) through their relationship with their providers and through their decisional involvement preferences. Providers are well aware of patient communication preferences but do not explicate underlying control needs. Implications for clinical practice are discussed.  相似文献   
5.
Carotid sonography is being performed on more than 5,000 participants in the Cardiovascular Health Study, a prospective, multicenter study of cardiovascular disease in men and women aged 65 years and older. The sonographic methods used to examine and measure the extracranial carotid arteries are described. Initial validation studies were performed on 61 subjects with a mean age of 68.6 years. Analysis of within- and between-sonographer differences and between-reader differences were performed for selected variables. In general, the mean absolute differences for within- and between-sonographer comparisons were small, with even less variability between readers. Variability was less for the common carotid artery than for the internal carotid artery. These data suggest that carotid sonography is a reliable and reproducible method for use in the study of carotid atherosclerosis in population studies.  相似文献   
6.
D M Dixon  A Polak 《Chemotherapy》1987,33(2):129-140
Amphotericin B (Amph B), 5-fluorocytosine (5-FC), ketoconazole (KTZ), fluconazole (FLZ), amorolfine (AMOR) and terbinafine (TER) were tested against 3 agents of central nervous system phaeohyphomycosis in vitro and in life-threatening infections in mice. The fungi studied were Cladosporium bantianum, Dactylaria constricta and Wangiella dermatitidis. The broadest protection against this group of fungi in mice was offered by 5-FC followed by Amph B and FLZ, then KTZ. AMOR and TER were inactive in vivo. The results of in vitro susceptibility testing had no predictive value. In contrast, the data obtained from the mouse models should be useful clinically.  相似文献   
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OBJECTIVE: Test the ability of glutathione monoethyl ester (GSH(e)) to protect auditory hair cells against the ototoxic effects of 4-hydroxy-2,3-nonenal (HNE). STUDY DESIGN AND SETTING: Organ of Corti explants were either untreated or treated with one of a series of four concentrations of GSH(e) for one day, then exposed to HNE. Counts of FITC-phalloidin-labeled hair cells determined both HNE ototoxicity and GSH(e) otoprotection. RESULTS: HNE was toxic to hair cells at physiologically relevant levels, eg, 400 muM, and GSH(e) provided a significant level of protection against HNE ototoxicity (P < 0.05) at all levels tested, ie, 1.16 to 9.3 mM. CONCLUSION: GSH(e) protects auditory hair cells from damage and loss initiated by a naturally occurring ototoxic molecule, ie, HNE (a by-product of oxidative stress). SIGNIFICANCE: Treatment with GSH(e) may be an effective therapy to protect the cochlea against the adverse effects of traumas (eg, electrode insertion) that generate oxidative stress.  相似文献   
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Virulence of Candida albicans mutants   总被引:5,自引:0,他引:5  
Annemarie Polak 《Mycoses》1992,35(1-2):9-16
Mutant strains of the fungal pathogen Candida albicans blocked in pyrimidine transport and salvage metabolism were tested for virulence in various animal models. The growth rate, germination and proteolytic enzyme production did not correlate with the virulence of the strains. However, a defect in the uridine transport system significantly decreased virulence in murine candidosis, although it had no effect in vaginal candidosis or in a Candida cyst model. It remains unclear whether this is due to the differing host defence mechanisms involved in systemic and superficial mycoses, or to the different requirements of the fungal systems for adherence and tissue invasion in the two types of infection.  相似文献   
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