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Chlorpyrifos (CP) is one of the organophosphate insecticides most used worldwide today. Although the main target organ for CP is the nervous system triggering predominantly neurotoxic effects, it has suggested other mechanisms of action as cytotoxicity and endocrine disruption. The risk posed by the pesticide metabolites on non-target organisms is increasingly recognized by regulatory agencies and natural resource managers. In the present study, cytotoxicity and estrogenic activity of CP, and its principal metabolite 3,5,6-trichloro-2-pyridinol (TCP) have been evaluated by in vitro assays, using two mammalian cell lines (HEK293 and N2a), and a recombinant yeast. Results indicate that TCP is more toxic than CP for the two cell lines assayed, being N2a cells more sensitive to both compounds. Both compounds show a similar estrogenic activity being between 2500 and 3000 times less estrogenic than 17β-estradiol. In order to find new toxicity measurement models, yeasts isolated from marine sediments containing CP residues have been tested against CP and TCP by cell viability assay. Of the 12 yeast strains tested, 6 of them showed certain sensitivity, and a concentration-dependent response to the tested compounds, so they could be considered as future models for toxicity tests, although further investigations and proves are necessary.

  相似文献   
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Coronary artery disease in patients with diabetes mellitus (DM) is characterized by extensive atherosclerosis, longer lesions, and diffuse distal disease. Consequently, these patients have worse outcomes after coronary revascularization, regardless of the modality used. Traditionally, coronary artery bypass grafting (CABG) has been regarded as more effective than percutaneous coronary intervention (PCI) in patients with DM, likely because of more complete revascularization and protection against disease progression in the bypass segment. Revascularization with balloon angioplasty, bare-metal stents, and first-generation drug-eluting stents have all been shown to be inferior to CABG in patients with DM. Current professional society guidelines reflect these findings, strongly recommending CABG over PCI in this setting. Newer stent platforms, however, have challenged this notion. The use of thinner struts, biocompatible polymer coating, and newer antiproliferative agents have improved the rates of cardiovascular events in patients with DM revascularized percutaneously. Since the publication of current guidelines, new studies suggested acceptable outcomes in patients with DM revascularized with second-generation drug-eluting stents, even though these conclusions are drawn from small subgroup analyses or nonrandomized studies. Robust registry data suggest similar mortality with lower rates of stroke after PCI compared with surgery, at the expense of increased rates of repeat revascularization. If complete revascularization can be achieved, similar rates of myocardial infarction are also observed. Therefore, contemporary revascularization in patients with DM with multivessel coronary artery disease should involve a multidisciplinary approach, in which interventional cardiologists and cardiac surgeons involve their patients to individualize treatment choices, and balance the risks and effectiveness of each modality.  相似文献   
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Hip fracture is a common serious complication of osteoporosis, which is associated with high morbidity and mortality. In nursing home residents, incidence rates of hip fractures are at least twice to three times higher than in community-dwellers of the same age and sex. Older adults with hip fracture have a 5- to 8-fold increased risk for all-cause mortality and much higher risk of institutionalization. Therefore, interventions to prevent institutionalization, prevent a second fracture in institutionalized patients, and decrease mortality after a hip fracture are highly needed. The orthogeriatrics model of care is a shared-care approach to patients after suffering a hip fracture. This program, which has been studied in models run by geriatricians with the assistance of a multidisciplinary team, includes a comprehensive medical and nursing admission assessment focusing on the patient’s premorbid function, cognition, comorbidities, and risks is followed by a comprehensive care plan design. This systematic review describes and analyzes the interrelation between hip fracture and nursing home placement taking into consideration those evidence-based interventions to prevent later complications and future institutionalization.  相似文献   
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Lateral left ventricular wall rupture (LVWR) is a rare complication following acute myocardial infarction (AMI) less than 1%. After cardiogenic shock, LVWR constitutes the most common cause of in‐hospital death in AMI patients. Around 40% of all LVWR occurred during the first 24 hours and 85% within the first week. In the present case, 76 hours following the intervention, LVWR was observed likely due to a small infarction at the lateral left ventricular wall possibly due to the marginal lesion. Our patient refused surgery and was followed clinically. Eighteen months later, real time three‐dimensional echocardiography showed a pseudoaneurysm.  相似文献   
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ObjectiveTo verify the impact of ischemic time on lung cell viability in an experimental model of lung ischemia–reperfusion (IR) injury and its repercussion on lung performance after reperfusion.MethodsTwenty-four animals were subjected to selective clamping of the left pulmonary artery and divided into four groups (n = 6) according to ischemic time: 15 (IR15), 30 (IR30), 45 (IR45), and 60 min (IR60). All animals were observed for 120 min after reperfusion. The hemodynamics, arterial blood gases measurements, and histologic changes were analyzed. Immunofluorescence assays for caspase 3 and annexin V were performed. Lipid peroxidation was assessed by thiobarbituric acid–reactive substances, and caspase 3 activity was assessed by colorimetric extract.ResultsThe partial pressure of arterial oxygen significantly decreased at the end of the observation period in the IR30, IR45, and IR60 groups (P < 0.05). The final mean arterial pressure significantly decreased in the IR60 group (P < 0.05). We observed a significant increase in caspase 3 activity and caspase 3–positive cells by immunofluorescence in the IR45 group compared with the other groups (P < 0.05). Additionally, there was an increase in necrotic cells assessed by annexin V in the IR60 group. The histologic score did not show differences among the different groups.ConclusionsThe degree of cell damage had a negative impact on lung performance. Sixty minutes of lung ischemia and posterior reperfusion resulted in an increased number of necrotic cells, suggesting that these cells may not be able to reverse the effects of the IR injury because of the lack of viable cells.  相似文献   
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The ALAT and SEPAR Treatment and Control of Smoking Groups have collaborated in the preparation of this document which attempts to answer, by way of PICO methodology, different questions on health interventions for helping COPD patients to stop smoking.The main recommendations are: (i) moderate-quality evidence and strong recommendation for performing spirometry in COPD patients and in smokers with a high risk of developing the disease, as a motivational tool (particularly for showing evidence of lung age), a diagnostic tool, and for active case-finding; (ii) high-quality evidence and strong recommendation for using intensive dedicated behavioral counselling and drug treatment for helping COPD patients to stop smoking; (iii) high-quality evidence and strong recommendation for initiating interventions for helping COPD patients to stop smoking during hospitalization with improvement when the intervention is prolonged after discharge, and (iv) high-quality evidence and strong recommendation for funding treatment of smoking in COPD patients, in view of the impact on health and health economics.  相似文献   
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