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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   
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It is unresolved whether elevated homocysteine in coronary artery disease (CAD) is the cause of arteriosclerosis or its consequence. In contrast, genetic variants of enzymes that metabolize homocysteine cannot be altered by arteriosclerosis. Consequently, their association with CAD would permit to imply causality. We modeled by regression analysis the effect of 11 variants in the methionine cycle upon CAD manifestation in 591 controls and 278 CAD patients. Among the examined variants only the carriership for the c.844ins68 in the cystathionine beta-synthase (CBS) gene was associated with a significantly lowered risk of CAD (OR=0.56; 95% CI=0.35-0.90 in the univariable, and OR=0.41, 95% CI=0.19-0.89 for obese people in the multivariable analysis, respectively). Healthy carriers of the c.844ins68 variant exhibited, compared to the wild type controls, significantly higher postload ratios of blood S-adenosylmethionine to S-adenosylhomocysteine (61.4 vs. 54.9, p=0.001) and of plasma total cysteine to homocysteine (8.6 vs. 7.3, p=0.004). The changes in these metabolites are compatible with an improved methylation status and with enhanced activity of homocysteine transsulfuration. In conclusion, the coincidence of clinical and biochemical effects of a common c.844ins68 CBS variant supports the hypothesis that compounds relating to homocysteine metabolism may play role in the development and/or progression of CAD.  相似文献   
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Aspartame is a sweetener introduced to replace the commonly used sucrose. It was discovered by James M. Schlatter in 1965. Being 180–200 times sweeter than sucrose, its intake was expected to reduce obesity rates in developing countries and help those struggling with diabetes. It is mainly used as a sweetener for soft drinks, confectionery, and medicines. Despite its widespread use, its safety remains controversial. This narrative review investigates the existing literature on the use of aspartame and its possible effects on the human body to refine current knowledge. Taking to account that aspartame is a widely used artificial sweetener, it seems appropriate to continue research on safety. Studies mentioned in this article have produced very interesting results overall, the current review highlights the social problem of providing visible and detailed information about the presence of aspartame in products. The studies involving the impact of aspartame on obesity, diabetes mellitus, children and fetus, autism, neurodegeneration, phenylketonuria, allergies and skin problems, its cancer properties and its genotoxicity were analyzed. Further research should be conducted to ensure clear information about the impact of aspartame on health.  相似文献   
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BackgroundIn this COVID‐19 era, we need to rethink the criteria used to measure the results of person‐centred care strategies.ObjectiveTo identify priorities, and criteria that health services can use to pursue actually the goal of achieving person‐centred care.DesignThree‐phase online qualitative study performed during May–July of 2020 using the Delphi technique.Setting and ParticipantsAn online platform was used for a consensus meeting of 114 participants, including health planning experts, health‐care institution managers, clinicians and patients.Main Outcome MeasuresCriteria and indicators for the achievement of person‐centred care.Main ResultsThe first round began with 125 proposals and 11 dimensions. After the second round, 28 ideas reached a high level of consensus among the participants. Ultimately, the workgroup agreed on 20 criteria for goals in the implementation of person‐centred care during the COVID‐19 era and 21 related indicators to measure goal achievement.DiscussionNine dimensions and 28 priorities were identified. These priorities are also in accordance with the quadruple aim approach, which emphasizes the need for care for health‐care professionals, without whom it is impossible to achieve a better quality of care.ConclusionsPerson‐centred care continues to be a key objective. However, new metrics are needed to ensure its continued development during the restoration of public health services beyond the control of COVID‐19.Patient or Public ContributionTwelve professionals and patient representatives participated voluntarily in the construction of the baseline questionnaire and in the selection of the criteria and indicators using an online platform for consensus meetings.  相似文献   
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Conclusions The multivalency of cold-reactive IgM anti-lymphocyte autoantibodies, together with the local density of reactive antigens on the cell surface, may confer a capacity for a variety of immunoregulatory and non-specific physiological roles in the immune system and in SLE and other autoimmune diseases. Targets of interest in this regard include CD45, 2 microglobulin, and surface immunoglobulin. IgG anti-lymphocyte autoantibodies, while more difficult to study, also exhibit interesting specificities. However, whether any of the mechanisms by which anti-lymphocyte autoantibodies could alter cellular function actually obtain in vivo remains speculative. Essentially all of the data in this regard derive from experiments in which anti-lymphocyte autoantibody-containing SLE serum or plasma, or purified Ig fractions thereof, is combined with peripheral blood mononuclear cells in short-term culture in vitro. Thus, it is possible that anti-lymphocyte autoantibodies in SLE, rather than contributing to pathogenesis, reflect a physiological attempt by the immune system to restore homeostasis in the face of aggressive autoimmune stimulation.  相似文献   
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The purpose of the study was the comparison of the effect of the oral therapy of non-insulin-dependent diabetes mellitus (NIDDM) with either a sulphonylurea or biguanide derivative on plasma amylin level. In 10 healthy individuals the fasting plasma amylin level was 1.56 +/- 0.27 pmol/l (mean +/- SEM) and 6 min after i.v. injection of 1 mg glucagon a fourfold increase was observed. In 10 patients with NIDDM receiving glibenclamide (CAS 10238-21-8) the fasting plasma amylin level was twofold higher than in healthy control (2.72 +/- 0.38 pmol/l; p < 0.025) but following glucagon administration it increased only twofold. In 15 patients treated with metformin (CAS 657-24-9) the fasting plasma amylin level was similar to that in healthy individuals (1.64 +/- 0.25 pmol/l), but after glucagon stimulation the increment of plasma amylin was minimal and the relevant mean value was significantly lower when compared with those in healthy individuals and with NIDDM patients treated with glibenclamide. In 10 untreated obese patients with newly diagnosed NIDDM the administration of glibenclamide (14 days) resulted in the increase of basal (2.47 +/- 0.23 and 3.16 +/- 0.29 pmol/l; p < 0.1), and glucagon stimulated (3.34 +/- 0.39 and 4.56 +/- 0.38; p < 0.05) plasma amylin concentrations, whereas other 10 patients receiving metformin showed a decrease in fasting plasma level of this peptide before (2.64 +/- 0.59 and 1.28 +/- 0.38 pmol/l; p < 0.1), and after glucagon injection (5.02 +/- 0.55 and 2.83 +/- 0.65 pmol/l; p < 0.02). With the respect to the trophic effect of amyloid deposits in the pancreatic islets and to a hypothetic effect of amylin increasing insulin resistance, the present results emphasize the particular usefulness of metformin in the pharmacological treatment of NIDDM. All contraindications and side effects of metformin should be taken into account before drug administration.  相似文献   
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Purpose

To study the use of functional capacity (FC) level and duration of aromatase inhibitor (AI) therapy with adiposity parameters in women with breast cancer.

Patients and Methods

FC was evaluated through the Health Assessment Questionnaire, which was assessed by classification and divided into 3 groups: G1 = mild to moderate difficulty, G2 = moderate to severe disability, and G3 = severe or very severe disability. Body mass, height, and waist circumference (WC) were measured, and body mass index (BMI) was calculated. Bioelectrical impedance analysis was used to calculate body fat (BF) and fat-free mass. The women were divided into 2 time groups (T1 and T2), which were determined by the median months of AI use (T1 ≤ 29.5 and T2 > 29.5 months).

Results

Impaired FC and adiposity parameters were significantly positively correlated. In addition, physical exercise was significantly lower in women assessed as G2 and G3 compared to those assessed as G1. The effect of FC on BMI, BF, and WC was also verified, as was the effect of the duration of AI receipt on BMI and BF. Women at T1 had significantly greater functional disability, BMI, and BF values. In addition, although not statistically significant, women in T1 who were assessed as G3 presented higher BMI, WC, and BF values than those in T2.

Conclusion

Adiposity above the recommended parameters and impaired FC were associated with the shortest time of receipt of adjuvant endocrine therapy with AI.  相似文献   
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