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Carlos A. Vaz Fragoso 《COPD》2016,13(2):125-129
Current epidemiologic practice evaluates COPD based on self-reported symptoms of chronic bronchitis, self-reported physician-diagnosed COPD, spirometry confirmed airflow obstruction, or emphysema diagnosed by volumetric computed chest tomography (CT). Because the highest risk population for having COPD includes a predominance of middle-aged or older persons, aging related changes must also be considered, including: 1) increased multimorbidity, polypharmacy, and severe deconditioning, as these identify mechanisms that underlie respiratory symptoms and can impart a complex differential diagnosis; 2) increased airflow limitation, as this impacts the interpretation of spirometry confirmed airflow obstruction; and 3) “senile” emphysema, as this impacts the specificity of CT-diagnosed emphysema. Accordingly, in an era of rapidly aging populations worldwide, the use of epidemiologic criteria that do not rigorously consider aging related changes will result in increased misidentification of COPD and may, in turn, misinform public health policy and patient care.  相似文献   
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Anemia represents a global health problem that negatively impacts quality of life in elderly population; however, its impact on the geriatric syndrome of frailty is unclear. We examined the prevalence of anemia among elderly and sought a relationship between hemoglobin and the phenotype of frailty. Baseline hemoglobin quintiles and anemia were assessed in relation to frailty status in a prospective study with 1,933 older community-dwelling adults enrolled in the Study on Aging and Dementia in Mexico (SADEM). Logistic regression was used to model the relationship between frailty and Hb, adjusting for risk factors of frailty, sociodemographic data, cognitive decline, chronic diseases, and some risky habits. Prevalence of frailty was 8.3 %. Frailty risk was highest at the lowest hemoglobin quintile (<14.3 g/dL for men; <13.3 g/dL for women), and 160 (8.3 %) were anemic (<13 g/dL for men; <12 g/dL for women). The relationship between frailty and Hb levels, adjusted for age and sex, observed in the first and fifth quintiles, compared with the fourth quintile, were 1.53 (95 % confidence interval (CI), 1.46–1.60) and 1.05 (95 % CI, 1.01–1.15). After multivariate adjustment, the odds ratios (ORs) were 1.23 (95 % CI, 1.17–1.13) and 1.06 (95 % CI, 1.01–1.11). The association was not diminished by risk factors for frailty (body mass index (BMI), comorbidity, cognitive decline, smoking, alcohol consumption, etc.). In community-dwelling older adults, low hemoglobin concentrations and anemia were independently associated with increased frailty risk. This suggests that mild anemia and low Hb levels are independent, modifiable risk factors for frailty.  相似文献   
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Neuroinflammation triggered by the expression of damaged-associated molecular patterns released from dying cells plays a critical role in the pathogenesis of ischemic stroke. However, the benefits from the control of neuroinflammation in the clinical outcome have not been established. In this study, the effectiveness of intranasal, a highly efficient route to reach the central nervous system, and intraperitoneal dexamethasone administration in the treatment of neuroinflammation was evaluated in a 60-min middle cerebral artery occlusion (MCAO) model in C57BL/6 male mice. We performed a side-by-side comparison using intranasal versus intraperitoneal dexamethasone, a timecourse including immediate (0 h) or 4 or 12 h poststroke intranasal administration, as well as 4 intranasal doses of dexamethasone beginning 12 h after the MCAO versus a single dose at 12 h to identify the most effective conditions to treat neuroinflammation in MCAO mice. The best results were obtained 12 h after MCAO and when mice received a single dose of dexamethasone (0.25 mg/kg) intranasally. This treatment significantly reduced mortality, neurological deficits, infarct volume size, blood–brain barrier permeability in the somatosensory cortex, inflammatory cell infiltration, and glial activation. Our results demonstrate that a single low dose of intranasal dexamethasone has neuroprotective therapeutic effects in the MCAO model, showing a better clinical outcome than the intraperitoneal administration. Based on these results, we propose a new therapeutic approach for the treatment of the damage process that accompanies ischemic stroke.Electronic supplementary materialThe online version of this article (10.1007/s13311-020-00884-9) contains supplementary material, which is available to authorized users.  相似文献   
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Familial Cancer - The risk of radiotherapy-induced malignancies (RIMs) is a concern when treating Li–Fraumeni syndrome (LFS) or Li–Fraumeni Like (LFL) patients. However, the type of...  相似文献   
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Khorchid A  Fragoso G  Shore G  Almazan G 《Glia》2002,40(3):283-299
Oligodendrocyte cultures were used to study the toxic effects of catecholamines. Our results showed that catecholamine-induced toxicity was dependent on the dose of dopamine or norepinephrine used and on the developmental stage of the cultures, with oligodendrocyte progenitors being more vulnerable. A role for oxidative stress and apoptosis on the mechanism of action of catecholamines on oligodendrocyte cell death was next assessed. Catecholamines caused a reduction in intracellular glutathione levels, an accumulation in reactive oxygen species and in heme oxygenase-1, the 32 kDa stress-induced protein. All these changes were prevented by N-acetyl-L-cysteine, a thiocompound with antioxidant activity and a precursor of glutathione, and were more pronounced in progenitors than mature cells, which could contribute to their higher susceptibility. Apoptotic cell death, as assessed by activation of caspase-9 and -3 and cleavage of poly(ADP-ribose) polymerase (a substrate of caspase-3), was only observed in oligodendrocyte progenitors. Pretreatment with zVAD, a general caspase inhibitor, prevented activation of caspase-9 and -3, DNA fragmentation, and decreased progenitors cell death. Furthermore, the expression levels of procaspase-3 and the ratio of the proapoptotic protein bax to antiapoptotic protein bcl-xl were several folds higher in immature than mature oligodendrocytes. Taken together, these results strongly suggest that the catecholamine-induced cytotoxicity in oligodendrocytes is developmentally regulated, mediated by oxidative stress, and have characteristics of apoptosis in progenitor cells.  相似文献   
27.
A historical cohort of children born between January 2000 and December 2002 from low-income families attending a primary health care facility on the periphery of Pelotas, Rio Grande do Sul, Brazil, was studied in relation to prevalence of exclusive breastfeeding. Analysis was based on a life table focusing on interruption of exclusive breastfeeding (month-by-month after birth) as the target outcome. Among the 112 children followed up from birth by the Well Baby Program, prevalence of exclusive breastfeeding in the first month of life was 95.0%, declining progressively to 81.0%, 64.0%, 53.0%, 39.0%, and 35.0%, respectively, from the second to the sixth month after birth. Median duration of exclusive breastfeeding was four months. Median duration of exclusive breastfeeding and prevalence among six-month-old infants were both higher than the Brazilian national rates and indicate the Program's adequacy in promoting breastfeeding. However, more effort should be made to increase the prevalence of exclusive breastfeeding until the sixth month of life.  相似文献   
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The S3Pvac synthetic vaccine composed of three peptides (GK1, KETc1 and KETc12) effectively protect against pig cysticercosis. Preliminary results point to an additional cysticidal capacity induced by S3Pvac or GK1 immunization. Herein, clear evidences of the cysticidal effect of S3Pvac but not of GK1 are presented. S3Pvac immunization of already experimentally infected pigs induced a reduction in the parasite load, in the vesicular cysticerci and in their viability. It also substantially increases the percent of histological damaged cysticerci more importantly in muscles than in brains, with a concomitant reduction in the antibody levels. Thus, S3Pvac represents a powerful means of controlling cysticercosis infection in pigs.  相似文献   
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BACKGROUND: There is substantial evidence that antidepressant medications treat moderate to severe depression effectively, but there is less data on cognitive therapy's effects in this population. OBJECTIVE: To compare the efficacy in moderate to severe depression of antidepressant medications with cognitive therapy in a placebo-controlled trial. DESIGN: Random assignment to one of the following: 16 weeks of medications (n = 120), 16 weeks of cognitive therapy (n = 60), or 8 weeks of pill placebo (n = 60). SETTING: Research clinics at the University of Pennsylvania, Philadelphia, and Vanderbilt University, Nashville, Tenn. PATIENTS: Two hundred forty outpatients, aged 18 to 70 years, with moderate to severe major depressive disorder. INTERVENTIONS: Some study subjects received paroxetine, up to 50 mg daily, augmented by lithium carbonate or desipramine hydrochloride if necessary; others received individual cognitive therapy. MAIN OUTCOME MEASURE: The Hamilton Depression Rating Scale provided continuous severity scores and allowed for designations of response and remission. RESULTS: At 8 weeks, response rates in medications (50%) and cognitive therapy (43%) groups were both superior to the placebo (25%) group. Analyses based on continuous scores at 8 weeks indicated an advantage for each of the active treatments over placebo, each with a medium effect size. The advantage was significant for medication relative to placebo, and at the level of a nonsignificant trend for cognitive therapy relative to placebo. At 16 weeks, response rates were 58% in each of the active conditions; remission rates were 46% for medication, 40% for cognitive therapy. Follow-up tests of a site x treatment interaction indicated a significant difference only at Vanderbilt University, where medications were superior to cognitive therapy. Site differences in patient characteristics and in the relative experience levels of the cognitive therapists each appear to have contributed to this interaction. CONCLUSION: Cognitive therapy can be as effective as medications for the initial treatment of moderate to severe major depression, but this degree of effectiveness may depend on a high level of therapist experience or expertise.  相似文献   
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