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Soils can be contaminated with substances arising from anthropogenic sources, but also with natural bioactive compounds produced by plants, such as terpenes and flavonoids. While terpenes and flavonoids have received much less attention from research studies than metals, the effects that phytocompounds can have on soil organisms such as beneficial microorganisms should not be neglected. Herein we report the sole and combined exposure of Rhizobium to cadmium, to the monoterpene alpha-pinene and to the flavanol quercetin. A range of environmentally relevant concentrations of the phytocompounds was tested. Physiological (growth, protein content and intracellular Cd concentration), oxidative damage (lipid peroxidation, protein carbonylation) and antioxidant mechanisms (superoxide dismutase, catalase, glutathione, glutathione-S-transferases, protein electrophoretic profiles) were assessed. Results suggest that exposure to both phytocompounds do not influence Rhizobium growth, but for combined exposure to phytocompounds and Cd, different responses are observed. At low concentrations, phytocompounds seem to relieve the stress imposed by Cd by increasing antioxidant responses, but at high concentrations this advantage is lost and membrane damage may even be exacerbated. Thus, the presence of bioactive phytocompounds in soil may influence the tolerance of microorganisms to persistent toxicants, and may change their impact on the environment.  相似文献   
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Background/Aim: The Glutathione S-transferases (GSTs) are important carcinogen-metabolizing enzymes. Polymorphisms involved in these enzymes can modulate the development and treatment of head and neck cancer. To investigate the association of GSTs polymorphisms with head and neck cancer and risk factors, clinical-pathological features, and survival time of the patients treated with chemotherapy and/or radiotherapy. Methods: The GST gene polymorphisms were evaluated in 197 cases and 514 controls by PCR-RFLP-Polymerase Chain Reaction Restriction Fragment Length Polymorphism. Results: The GSTP-313 was associated with a decreased risk for HNSCC (p=0.050). The GSTP1 haplotype analysis revealed a higher frequency of the AC and AT haplotypes in the case group than in the control group (p=0.013 and p=0.019, respectively), and the opposite for G-C haplotype (p = 0.015). Yet, the different combinations between the genotypes were associated with an increased risk of cancer. The study showed no association between the polymorphisms and primary tumor site, clinical-pathological characteristics, treatment (chemotherapy and/or radiotherapy) and survival time of the patients. Conclusion: The GST polymorphisms combination showed an increased risk for carcinogenesis, and studies with larger casuistry can contribute to the clarification of the role in individual patient differences for the response to chemotherapy and/or radiotherapy and identify biomarkers of susceptibility.  相似文献   
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Abstract

Aim: To analyze the effects of body weight loss on bone mineral density (BMD) on hip (Hip BMD) and lumbar spine (Lumbar BMD) after six months of bariatric surgery. Bariatric surgery is an effective treatment for morbid obesity. Nonetheless, there are scant data on the effect of weight bearing on bone structure.

Material and methods: Seventeen obese women aged 41.2?±?11.3 yrs. who underwent Roux-en-Y gastric bypass (RYGB) were included. Body composition assessments were performed through dual-energy X-ray absorptiometry immediately before and after 6-months RYGB. Data collected pre- and post-RYGB included total body weight, body mass index (BMI), lean body mass (LM), fat mass (FM) and bone mineral content. The pre- (PRE) and post-operative (POST) results were compared.

Results: Lumbar BMD POST presented a non-significant loss of 1.8% whereas Hip BMD POST showed a significant loss of 17.8%. The analysis demonstrated that BMI and LM PRE explained 26% and 49%, respectively, of Hip BMD PRE variability. In addition, LM POST explained 30% of hip BMD POST variability and was not significant for Lumbar BMD POST.

Conclusions: Obesity and rapid weight loss showed direct influence in Hip BMD after six months of bariatric surgery. However, its effect on the lumbar spine area was smaller due to the higher capacity of the spine to dissipate loads through its curvature.  相似文献   
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Introduction: The addition of monoclonal antibody (mAb) epidermal growth factor receptor (EGFR) inhibitors to classic chemotherapy doublet backbones has improved survival of metastatic colorectal cancer (mCRC). However, the role of triple-drug chemotherapy regimens in combination with an anti-EGFR mAb inhibitor is not yet clear.

Areas covered: The activity of triple-drug chemotherapy regimens when combined with an anti-EGFR mAb in mCRC patients is examined. We describe the overall safety and tolerability profiles based on a literature review of all published phase I and II clinical trials in this setting. Drug exposure, tumor mutational status, and metastases resectability are discussed. A review of PubMed and abstracts of major oncology congresses from 2009 to 2018, with MeSH and full-text search terms for clinical trials of anti-EGFR for ‘metastatic’ or ‘advanced’ ‘colorectal cancer/adenocarcinoma’ was implemented. Only English language publications were included.

Expert opinion: Efficacy data from phase II trials are promising, but the safety profiles are not as encouraging; the development of severe diarrhea and acneiform rash limit the drug exposure that is critical for improved outcomes. Phase II studies of these triplet chemotherapy/anti-EGFR mAb combinations have focused on conversion therapy in liver-limited disease or in the first-line setting in advanced disease. The identification of biomarkers of response and toxicity may support the use of personalized medicine and more precise design of phase III trials.  相似文献   

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IntroductionErectile dysfunction (ED) is associated with neurological damage due to human T-lymphotropic virus 1 (HTLV-1) infection, but hormonal and psychogenic factors also cause ED.AimTo evaluate the association of psychogenic and hormonal factors with ED in men infected with HTLV-1.MethodsIn this cross-sectional study, we compared total testosterone, follicle stimulating hormone, luteinizing hormone, prolactin, anxiety symptoms, depressive symptoms, and neurologic manifestations in HTLV-1-infected men with or without ED. The International Index of Erectile Function was used to determine the degree of ED. Participants were grouped according to Osame’s Motor Disability Scale and the Expanded Disability Status Scale: HTLV-1-associated myelopathy or tropical spastic paraparesis (HAM/TSP), probable HAM/TSP, or HTLV-1 carrier. Chi-square and Fisher’s exact tests were used to compare the groups, and regression analyses were used to show predictors of ED.Main Outcome MeasureSexual hormonal levels, psychogenic factors, and neurologic disabilities were found to be associated with ED.ResultsED was associated with age older than 60 years (P < .001), degree of neurologic involvement (P < .001), depression (P = .009), and anxiety (P = .008). In the multivariate analyses, only age and degree of neurological injury remained as risk factors for ED.Clinical ImplicationsNeurological manifestations are a stronger predictor of ED than hormonal and psychogenic factors in HTLV-1-infected men.Strengths & LimitationsThe statistical power of the study was limited due to the low number of participants, but neurologic manifestations were clearly associated with ED. There was no strong association between hormonal and psychogenic factors and ED.ConclusionHormonal and psychogenic factors did not show a strong association with ED in individuals with HTLV-1, but neurological manifestations were strongly associated with ED in these individuals.de Oliveira CJV, Neto, JAC, Andrade RCP, et al. Hormonal and Psychogenic Risk Factors for Erectile Dysfunction in Men with HTLV–1. J Sex Med 2019; 16:1763–1768.  相似文献   
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