Summary The Brazilian Osteoporosis Study (BRAZOS) is the first epidemiological study carried out in a representative sample of Brazilian men and women aged 40 years or older. The prevalence of ...fragility fractures is about 15.1% in the women and 12.8% in the men. Moreover, advanced age, sedentarism, family history of hip fracture, current smoking, recurrent falls, diabetes mellitus and poor quality of life are the main clinical risk factors associated with fragility fractures. Introduction The Brazilian Osteoporosis Study (BRAZOS) is the first epidemiological study carried out in a representative sample of Brazilian men and women aged 40 years or older with the purpose of identifying the prevalence and the main clinical risk factors (CRF) associated with osteoporotic fracture in our population. Methods A total of 2,420 individuals (women, 70%) from 150 different cities in the five geographic regions in Brazil, and all different socio-economical classes were selected to participate in the present survey. Anthropometrical data as well as life habits, fracture history, food intake, physical activity, falls and quality of life were determined by individual quantitative interviews. The representative sampling was based on Brazilian National data provided by the 2000 and 2003 census. Low trauma fracture was defined as that resulting of a fall from standing height or less in individuals 50 years or older at specific skeletal sites: forearm, femur, ribs, vertebra and humerus. Sampling error was 2.2% with 95% confidence intervals. Logistic regression analysis models were designed having the fragility fracture as the dependent variable and all other parameters as the independent variable. Significance level was set as p < 0.05. Results The average of age, height and weight for men and women were 58.4 ± 12.8 and 60.1 ± 13.7 years, 1.67 ± 0.08 and 1.56 ± 0.07 m and 73.3 ± 14.7 and 64.7 ± 13.7 kg, respectively. About 15.1% of the women and 12.8% of the men reported fragility fractures. In the women, the main CRF associated with fractures were advanced age (OR = 1.6; 95% CI 1.06-2.4), family history of hip fracture (OR = 1.7; 95% CI 1.1-2.8), early menopause (OR = 1.7; 95% CI 1.02-2.9), sedentary lifestyle (OR = 1.6; 95% CI 1.02-2.7), poor quality of life (OR = 1.9; 95% CI 1.2-2.9), higher intake of phosphorus (OR = 1.9; 95% CI 1.2-2.9), diabetes mellitus (OR = 2.8; 95% CI 1.01-8.2), use of benzodiazepine drugs (OR = 2.0; 95% CI 1.1-3.6) and recurrent falls (OR = 2.4; 95% CI 1.2-5.0). In the men, the main CRF were poor quality of life (OR = 3.2; 95% CI 1.7-6.1), current smoking (OR = 3.5; 95% CI 1.28-9.77), diabetes mellitus (OR = 4.2; 95% CI 1.27-13.7) and sedentary lifestyle (OR = 6.3; 95% CI 1.1-36.1). Conclusion Our findings suggest that CRF may contribute as an important tool to identify men and women with higher risk of osteoporotic fractures and that interventions aiming at specific risk factors (quit smoking, regular physical activity, prevention of falls) may help to manage patients to reduce their risk of fracture.
Although the close link between body weight and fertility has been known for eons, only recently have the peripheral signals and neuroendocrine networks responsible for such a phenomenon begun to be ...identified. A key event in this field was the cloning of the adipocyte-derived hormone leptin, which has been demonstrated as a pivotal regulator for the integration of energy homeostasis and reproduction. In addition, other metabolic hormones, such as insulin, contribute to this physiological integration. Moreover, compelling experimental evidence implicates hormonal products of the gastrointestinal tract as adjuncts in the complex coordination and regulation of body weight and reproduction. Here, we review recent studies evaluating the reproductive effects and sites of action of ghrelin and PYY
3-36, two hormonal signals of gastrointestinal origin involved in the control food intake and energy balance. In addition, we summarize the potential contribution of kisspeptin, the recently characterized gatekeeper of the GnRH system encoded by
Kiss1 gene, to integrating reproductive function and energy status. Evidence suggests that besides having direct gonadal effects, ghrelin may participate in the regulation of gonadotropin secretion and it may influence the timing of puberty. Likewise, PYY
3-36 modulates GnRH and gonadotropin release. In addition, the hypothalamic KiSS-1 system is sensitive to nutritional status, and its diminished expression during states of negative energy balance might contribute to the suppression of reproductive function in such conditions. We propose that the peripheral hormones, ghrelin and PYY
3-36, and the central neuropeptide, kisspeptin, are ‘novel’ players in the neuroendocrine networks that integrate energy balance and reproduction.
Taking on what one former U.S. ambassador called “the last ghost of the Vietnam War,” this book examines the farreaching impact of Agent Orange, the most infamous of the dioxincontaminated herbicides ...used by American forces in Southeast Asia. Edwin A. Martini’s aim is not simply to reconstruct the history of the “chemical war” but to investigate the ongoing controversy over the short and longterm effects of weaponized defoliants on the environment of Vietnam, on the civilian population, and on the troops who fought on both sides. Beginning in the early 1960s, when Agent Orange was first deployed in Vietnam, Martini follows the story across geographical and disciplinary boundaries, looking for answers to a host of still unresolved questions. What did chemical manufacturers and American policymakers know about the effects of dioxin on human beings, and when did they know it? How much do scientists and doctors know even today? Should the use of Agent Orange be considered a form of chemical warfare? What can, and should, be done for U.S. veterans, Vietnamese victims, and others around the world who believe they have medical problems caused by Agent Orange? Martini draws on military records, government reports, scientific research, visits to contaminated sites, and interviews to disentangle conflicting claims and evaluate often ambiguous evidence. He shows that the impact of Agent Orange has been global in its reach affecting individuals and communities in New Zealand, Australia, Korea, and Canada as well as Vietnam and the United States. Yet for all the answers it provides, this book also reveals how much uncertainty—scientific, medical, legal, and political—continues to surround the legacy of Agent Orange.
Display omitted
•The methane to methanol reaction was studied by operando XAS on two Cu-MOR zeolites.•CH4-loading and steam-assisted CH3OH-extraction steps were followed with two different ...protocols.•Linear Combination Fit analysis was applied to time-dependent XANES spectra.•The Cu(I) component formed during CH4-loading correlates with normalized CH3OH yield.•EXAFS showed substantial rearrangement of Cu local structure during CH4-loading.
The direct methane to methanol (DMTM) conversion is often referred to as a ‘dream reaction’ with enormous potential to alter energy sector and chemical industry. After O2-activation, Cu-exchanged zeolites form CuxOy species that activate CH4 and release it in the form of CH3OH upon interaction with H2O. Despite extensive research efforts in the last years, several questions concerning the influence of materials composition and process parameters on the reaction mechanism remain open. Herein, we characterize Cu-MOR zeolites with different composition by operando X-ray absorption spectroscopy (XAS), monitoring their spectroscopic response under two characteristic DMTM reaction protocols varied in the duration of the key reaction steps. Linear Combination Fit (LCF) analysis of the time-resolved X-ray absorption near edge structure (XANES) spectra collected during CH4-loading and steam-assisted CH3OH extraction enabled to quantify the abundance of different Cu species during these two steps. Data analysis revealed a positive linear correlation between the methanol yield generated per incorporated copper and the Cu(I) component formed during the CH4-loading step. Cu(I) development during CH4-loading is accompanied by modifications in the extended X-ray absorption fine structure (EXAFS) spectra suggesting substantial rearrangement in the active site structure. The obtained results provide new mechanistic insights for the DMTM over Cu-MOR.
Hearing loss may be genetic, associated with aging or exposure to noise or ototoxic substances. Its aetiology can be attributed to vascular injury, trauma, tumours, infections or autoimmune response. ...All these factors could be related to alterations in cochlear microcirculation resulting in hypoxia, which in turn may damage cochlear hair cells and neurons, leading to deafness. Hypoxia could underlie the aetiology of deafness, but very few data about it are presently available. The aim of this work is to develop animal models of hypoxia and ischemia suitable for study of cochlear vascular damage, characterizing them by electrophysiology and gene/protein expression analyses. The effects of hypoxia in infarction were mimicked in rat by partial permanent occlusion of the left coronary artery, and those of ischemia in thrombosis by complete temporary carotid occlusion. In our models both hypoxia and ischemia caused a small but significant hearing loss, localized at the cochlear apex. A slight induction of the coagulation cascade and of oxidative stress pathways was detected as cell survival mechanism, and cell damages were found on the cuticular plate of outer hair cells only after carotid ischemia. Based on these data, the two developed models appear suitable for in vivo studies of cochlear vascular damage.
•Hypoxia and ischemia cause hearing loss.•Carotid ischemia leads to hair cells damage.•Coagulation and oxidation pathways are involved.
Abstract Objective In addition to the importance of adequate calcium and vitamin D status for health and prevention of several chronic diseases, a high prevalence of both nutrient inadequacy and ...25-hydroxyvitamin D (25OHD) insufficiency has been observed. The aim of this study was to estimate calcium and vitamin D status correlates and adequacy from a population-based epidemiologic study. Methods This is a subsample of a cross-sectional study of a representative sample of individuals living in São Paulo that includes 636 participants. A 24-h dietary record and a blood sample were collected. Nutrient adequacy was estimated by adjusting for the within-person variance of the nutrient intake. Serum concentration of 25(OH)D was measured by high-performance liquid chromatography and considered adequate when ≥ 50 nmol/L. Results Calcium and vitamin D intake decrease according to life stages in both men and women, and increases with family income and educational level. The prevalence of calcium intake inadequacy is higher than 70% and almost 100% for vitamin D. The highest 25(OH)D concentration was observed in the fall—51.7 (20.4) nmol/L—and lowest in the summer—30.1 (8.8) nmol/L. Sex, body mass index, physical activity, alcohol and smoking habits, life stage, family income, skin color, waist circumference, and season of the year could explain 22% of the variability of 25(OH)D. Conclusions The present study demonstrates important inadequacies regarding the nutritional status of calcium and vitamin D and indicates an urgent need not only for health professionals, but also for government and food industries to undertake new initiatives that could result in a real improvement in terms of calcium and vitamin D nutrition.
Idiopathic sudden sensorineural hearing loss (ISSNHL) represents an acute inner ear disorder with an overall incidence of 5-20/100000 individuals per year in western countries. No clear causes for ...this disease have been found so far, but cochlear ischemia has been hypothesized as one of the etiopathological mechanisms. The aim of our study was to assess the role of diabetes and traditional cardiovascular risk factors in the pathogenesis of ISSNHL.
Case-control study of 141 patients (75 males/66 females) matched for age and gender. Cases were affected by ISSNHL, defined as a sudden hearing loss > or =30 dB, within 3 frequencies, developing over 72 h. The control group was composed of 271 sex- and age-matched subjects (142 males/129 females) who agreed to participate in this observational study and provided blood samples for laboratory investigations. Cardiovascular risk factors examined were: diabetes mellitus, smoking history, hypercholesterolemia, hypertriglyceridemia and hypertension.
On the univariate analysis, diabetes prevalence was higher in the ISSNHL group (15.6%) compared to controls (8.5%) (p = 0.03). Also hypercholesterolemia was significantly more frequent in the ISSNHL group compared to the control population. There were no statistically significant differences between the 2 populations concerning other cardiovascular risk factors. The risk of ISSNHL tended to increase as the number of cardiovascular risk factors increased (p for linear trend = 0.018).
Our findings suggest that diabetes mellitus, hypercholesterolemia and a high burden of cardiovascular risk factors are associated with the risk of ISSNHL.
Abstract It has been demonstrated, in normal and aged rats and mice, that acute i.c.v. ghrelin (Ghr) administration increases memory retention. In order to evaluate if this treatment, restores memory ...retention in animals exhibiting impaired memory, in the present work we selected a chronic food restriction mouse model (since undernutrition prejudices higher nervous functions). We employed adult female mice with 28 days of 50% food restriction and evaluated: a) behavioral performance using novel object recognition test for memory, and plus maze for anxiety-like behavior, b) some morphometric parameters as body and hepatic weights and c) plasma Ghr levels. The animals with 50% food restriction showed an increase in plasma Ghr levels and a decrease in morphometric parameters and in the percentage of novel object recognition time. When the peptide was i.c.v. injected in food-restricted animals (0.03, 0.3 or 3.0 nmol/μl), memory increases in relation to food-restricted mice injected with vehicle, reaching a performance similar to controls.
An innovative approach for the optimal matching of independently optimum sum and difference patterns through sub-arrayed monopulse linear arrays is presented. By exploiting the relationship between ...the independently optimal sum and difference excitations, the set of possible solutions is considerably reduced and the synthesis problem is recast as the search of the best solution in a noncomplete binary tree. Towards this end, a fast resolution algorithm that exploits the presence of elements more suitable to change subarray membership is presented. The results of a set of numerical experiments are reported in order to validate the proposed approach pointing out its effectiveness also in comparison with state-of-the-art optimal matching techniques.
PDF