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41.
Melikian Assieh A.; Leszczynska Joanna M.; Hecht Stephen S.; Hoffmann Dietrich 《Carcinogenesis》1986,7(1):9-15
We have studied the effects of the co-carcinogen catechol (1,2-dihydroxybenzene)on the metabolic activation of [3H] benzo[a]pyrene (BaP) inmouse skin, in vivo and on the binding of BaP metabolites toDNA and protein at intervals from 0.524 h. Upon topicalapplication of 0.015 mg [3H]BaP and 0.25 or 0.5 mg catecholper mouse, catechol had little effect on the total amount of[3H]BaP metabolized in mouse skin, but it affected the relativeproportions of [3H]BaP metabolites. Catechol (0.5 mg/mouse)decreased the proportion of watersoluble [3H]BaP metabolites,ethyl acetate-soluble polar metabolites and quinones, but doubledthe levels of unconjugated 3-hydroxy-BaP at all measured intervalsafter treatment. Catechol also caused a small increase in thelevels of trans-7,8-dihydroxy-7,8-dihydroBaP and trans-9,10-dihydroxy-9,10-dihydroBaP0.5 h after treatment. Two hours after treatment, the levelsof these metabolites subsided to those of the controls. Catecholdid not affect the levels of glutathione conjugates of BaP.However, it caused a decrease in glucuronide and sulphate conjugateformation from BaP. Catechol caused an 2-fold increase in theformation of anti-7, 8-dihydroxy-9, 10-epoxy-7, 8, 9, 10-tetrahydroBaP(BPDE) DNA adducts and elevated the ratio of anti-syn-BPDE-DNAadducts 1.6 to 2.9-fold. Catechol treatment increased the radioactivityassociated with epidermal proteins after [3H]BaP application.Because catechol increased levels of 3-hydroxyBaP, we consideredthe possibility that 3-hy-droxyBaP might enhance the tumor initiatingactivities of BaP or BPDE in mouse skin; a bioassay demonstratedthat this was not the case. The results of this study indicatethat one important effect of catechol related to its co-carcinogenicityis its ability to enhance formation of anti-BPDE-DNA adductsin mouse skin. 相似文献
42.
Belanoff Candice Alade Mayowa Oluwatosin Almeida Joanna 《Maternal and child health journal》2022,26(4):834-844
Maternal and Child Health Journal - Foreign-born non-Hispanic Black (NHB) birthing parents are less likely to have a preterm birth (PTB) than US-born NHBs. There is further variation by region and... 相似文献
43.
Medicine, Health Care and Philosophy - In contrast to most publications on the ethics of paying research subjects, which start by identifying and analyzing major ethical concerns raised by the... 相似文献
44.
ukasz Kopiasz Katarzyna Dziendzikowska Magorzata Gajewska Micha Oczkowski Kinga Majchrzak-Kuligowska Tomasz Krlikowski Joanna Gromadzka-Ostrowska 《Nutrients》2021,13(2)
Background: Crohn’s disease (CD) is characterized by chronic inflammation of the gastrointestinal tract with alternating periods of exacerbation and remission. The aim of this study was to determine the time-dependent effects of dietary oat beta-glucans on colon apoptosis and autophagy in the CD rat model. Methods: A total of 150 Sprague–Dawley rats were divided into two main groups: healthy control (H) and a TNBS (2,4,6-trinitrobenzosulfonic acid)-induced colitis (C) group, both including subgroups fed with feed without beta-glucans (βG−) or feed supplemented with low- (βGl) or high-molar-mass oat beta-glucans (βGh) for 3, 7, or 21 days. The expression of autophagy (LC3B) and apoptosis (Caspase-3) markers, as well as Toll-like (TLRs) and Dectin-1 receptors, in the colon epithelial cells, was determined using immunohistochemistry and Western blot. Results: The results showed that in rats with colitis, after 3 days of induction of inflammation, the expression of Caspase-3 and LC3B in intestinal epithelial cells did not change, while that of TLR 4 and Dectin-1 decreased. Beta-glucan supplementation caused an increase in the expression of TLR 5 and Dectin-1 with no changes in the expression of Caspase-3 and LC3B. After 7 days, a high expression of Caspase-3 was observed in the colitis-induced animals without any changes in the expression of LC3B and TLRs, and simultaneously, a decrease in Dectin-1 expression was observed. The consumption of feed with βGl or βGh resulted in a decrease in Caspase-3 expression and an increase in TLR 5 expression in the CβGl group, with no change in the expression of LC3B and TLR 4. After 21 days, the expression of Caspase-3 and TLRs was not changed by colitis, while that of LC3B and Dectin-1 was decreased. Feed supplementation with βGh resulted in an increase in the expression of both Caspase-3 and LC3B, while the consumption of feed with βGh and βGl increased Dectin-1 expression. However, regardless of the type of nutritional intervention, the expression of TLRs did not change after 21 days. Conclusions: Dietary intake of βGl and βGh significantly reduced colitis by time-dependent modification of autophagy and apoptosis, with βGI exhibiting a stronger effect on apoptosis and βGh on autophagy. The mechanism of this action may be based on the activation of TLRs and Dectin-1 receptor and depends on the period of exacerbation or remission of CD. 相似文献
45.
Micha Oczkowski Katarzyna Dziendzikowska Anna Pasternak-Winiarska Dariusz Wodarek Joanna Gromadzka-Ostrowska 《Nutrients》2021,13(2)
Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer. 相似文献
46.
Most nutrition studies looking at the association of food with cardiometabolic markers rely on food frequency questionnaires, which are prone to recall bias. Pentadecanoic acid, heptadecanoic acid and trans-palmitoleic acid are fatty acids that are not synthesized endogenously but are obtained from the diet, particularly dairy, making them reasonable biomarkers of dairy consumption. We investigated the association of dairy fatty acid biomarkers with glycated hemoglobin (HbA1c) and cardiovascular risk factors in type 2 diabetes (T2D). In a clinical trial, 111 participants with T2D (age 58.5 ± 8.9 years, HbA1c 8.09 ± 0.96%) were randomized into three groups: a control group that maintained baseline dairy intake, a low-fat (LF) group that incorporated ≥3 servings/day of LF dairy and a high-fat (HF) group that incorporated ≥3 servings/day of HF dairy. We compared the fatty acids (FA) composition between the three groups at 24 weeks. Pentadecanoic acid and trans-palmitoleic acid increased in the HF group by 14.1% ± 5.4% and 17.5% ± 5.1%, respectively, but not in the control and LF groups (p = 0.0474 and p = 0.0025 for group-by-time interaction, respectively). Those increases were positively associated with changes in total cholesterol, very-low-density lipoprotein cholesterol VLDL-C and triglycerides but were not associated with changes in HbA1c from baseline to 24 weeks. These results suggest that the intervention was successful and that participants were likely compliant, which supports the validity of the main trial. 相似文献
47.
Monika Grabia Anna Pucion-Jakubik Renata Markiewicz-ukowska Joanna Bielecka Anita Mielech Patryk Nowakowski Katarzyna Socha 《Nutrients》2021,13(4)
An appropriate balanced diet and dietary patterns are important at every stage of life, but in the case of young patients with type 1 diabetes mellitus (T1DM), it is especially crucial during the COVID-19 pandemic. The aim of the study was to assess health and nutritional behaviors, mainly adherence to the Mediterranean diet (MD), during the second wave of the COVID-19 pandemic in Poland among women with T1DM, and to compare them with a healthy population. This survey (based on a questionnaire) was conducted in December 2020 and included 219 young women, healthy (n = 106) and with T1DM (n = 113), from northeast Poland. Over 30% of the study group admitted that they did not engage in any physical activity. A large proportion declared that their screen time was 5–7 h a day (48% in control and 40% in T1DM group). High intakes of sweet-beverages, sweets and red meat, but also low intakes of olive oil, fish and nuts were observed. The vast majority of participants (60% vs. 71%) were moderately adherent to the Mediterranean Diet Adherence Screener (MEDAS). The study demonstrated that despite the similarity between the behaviors of healthy people and those with T1DM, negative health and nutritional practices, such as low physical activity, long screen time, medium and high levels of stress and inappropriate eating habits were observed. 相似文献
48.
Joanna Rees Simone Radavelli Bagatini Johnny Lo Jonathan M. Hodgson Claus T. Christophersen Robin M. Daly Dianna J. Magliano Jonathan E. Shaw Marc Sim Catherine P. Bondonno Lauren C. Blekkenhorst Joanne M. Dickson Joshua R. Lewis Amanda Devine 《Nutrients》2021,13(5)
Increasing prevalence of mental health disorders within the Australian population is a serious public health issue. Adequate intake of fruits and vegetables (FV), dietary fibre (DF) and resistant starch (RS) is associated with better mental and physical health. Few longitudinal studies exist exploring the temporal relationship. Using a validated food frequency questionnaire, we examined baseline FV intakes of 5845 Australian adults from the AusDiab study and estimated food group-derived DF and RS using data from the literature. Perceived mental health was assessed at baseline and 5 year follow up using SF-36 mental component summary scores (MCS). We conducted baseline cross-sectional analysis and prospective analysis of baseline dietary intake with perceived mental health at 5 years. Higher baseline FV and FV-derived DF and RS intakes were associated with better 5 year MCS (p < 0.001). A higher FV intake (754 g/d vs. 251 g/d, Q4 vs. Q1) at baseline had 41% lower odds (OR = 0.59: 95% CI 0.46–0.75) of MCS below population average (<47) at 5 year follow up. Findings were similar for FV-derived DF and RS. An inverse association was observed with discretionary food-derived DF and RS. This demonstrates the association between higher intakes of FV and FV-derived DF and RS with better 5 year mental health outcomes. Further RCTs are necessary to understand mechanisms that underlie this association including elucidation of causal effects. 相似文献
49.
Habib Ndema Steyn Petrus S. Boydell Victoria Cordero Joanna Paula Nguyen My Huong Thwin Soe Soe Nai Dela Shamba Donat Kiarie James 《Health services & outcomes research methodology》2021,21(2):188-205
Health Services and Outcomes Research Methodology - An interrupted time series with a parallel control group (ITS-CG) design is a powerful quasi-experimental design commonly used to evaluate the... 相似文献
50.
Joanna Paladino Suzanne Mitchell Namita Mohta Joshua R. Lakin Nora Downey Erik K. Fromme Sue Gullo Evan Benjamin Justin J. Sanders 《Joint Commission journal on quality and patient safety / Joint Commission Resources》2021,47(2):127-136
The COVID-19 pandemic has exposed the medical and social vulnerability of an unprecedented number of people. Consequently, there has never been a more important time for clinicians to engage patients in advance care planning (ACP) discussions about their goals, values, and preferences in the event of critical illness. An evidence-based communication tool—the Serious Illness Conversation Guide—was adapted to address COVID-related ACP challenges using a user-centered design process: convening relevant experts to propose initial guide adaptations; soliciting feedback from key clinical stakeholders from multiple disciplines and geographic regions; and iteratively testing language with patient actors. With feedback focused on sharing risk about COVID-19–related critical illness, recommendations for treatment decisions, and use of person-centered language, the team also developed conversation guides for inpatient and outpatient use. These tools consist of open-ended questions to elicit perception of risk, goals, and care preferences in the event of critical illness, and language to convey prognostic uncertainty. To support use of these tools, publicly available implementation materials were also developed for clinicians to effectively engage high-risk patients and overcome challenges related to the changed communication context, including video demonstrations, telehealth communication tips, and step-by-step approaches to identifying high-risk patients and documenting conversation findings in the electronic health record. Well-designed communication tools and implementation strategies can equip clinicians to foster connection with patients and promote shared decision making. Although not an antidote to this crisis, such high-quality ACP may be one of the most powerful tools we have to prevent or ameliorate suffering due to COVID-19. 相似文献