56 resultados para Relation of Drought to Water-Use in Nebraska


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BACKGROUND: Little information is available on the validity of simple and indirect body-composition methods in non-Western populations. Equations for predicting body composition are population-specific, and body composition differs between blacks and whites. OBJECTIVE: We tested the hypothesis that the validity of equations for predicting total body water (TBW) from bioelectrical impedance analysis measurements is likely to depend on the racial background of the group from which the equations were derived. DESIGN: The hypothesis was tested by comparing, in 36 African women, TBW values measured by deuterium dilution with those predicted by 23 equations developed in white, African American, or African subjects. These cross-validations in our African sample were also compared, whenever possible, with results from other studies in black subjects. RESULTS: Errors in predicting TBW showed acceptable values (1.3-1.9 kg) in all cases, whereas a large range of bias (0.2-6.1 kg) was observed independently of the ethnic origin of the sample from which the equations were derived. Three equations (2 from whites and 1 from blacks) showed nonsignificant bias and could be used in Africans. In all other cases, we observed either an overestimation or underestimation of TBW with variable bias values, regardless of racial background, yielding no clear trend for validity as a function of ethnic origin. CONCLUSIONS: The findings of this cross-validation study emphasize the need for further fundamental research to explore the causes of the poor validity of TBW prediction equations across populations rather than the need to develop new prediction equations for use in Africa.

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Knowledge of the hormonal pathway controlling genotype-specific norms of reaction would shed light on the ecological factors to which each genotype is adapted. Environmentally mediated changes in the sign and magnitude of covariations between heritable melanin-based colouration and fitness components are frequent, revealing that extreme melanin-based phenotypes can display different physiological states depending on the environment. Yet, the hormonal mechanism underlying this phenomenon is poorly understood. One novel hypothesis proposes that these covariations stem from pleiotropic effects of the melanocortin system. Melanocortins are post-translationally modified bioactive peptides derived from the POMC prohormone that are involved in melanogenesis, anti-inflammation, energy homeostasis and stress responses. Thus, differential regulation of fitness components in relation to environmental factors by pale and dark melanic individuals may be due to colour-specific regulation of the POMC prohormone. Accordingly, we found that the degree of reddish melanic colouration was negatively correlated with blood circulating levels of the POMC prohormone in female tawny owls (Strix aluco) rearing a brood for which the size was experimentally reduced, but not when enlarged, and in females located in rich but not in poor territories. Our findings support the hypothesis that the widespread links between melanin-based colouration and fitness components may be mediated, at least in part, by the melanocortin system.

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Rapid response to: Ortegón M, Lim S, Chisholm D, Mendis S. Cost effectiveness of strategies to combat cardiovascular disease, diabetes, and tobacco use in sub-Saharan Africa and South East Asia: mathematical modelling study. BMJ. 2012 Mar 2;344:e607. doi: 10.1136/bmj.e607. PMID: 22389337.

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Objectives: After several years of increasing 'normalisation' of cannabis use in Switzerland at the beginning of the new millennium, a reversed tendency, marked among others by a more stringent law-enforcement, set in. The presentation examines the question of where adolescents and young adults obtained cannabis, within the context of this societal change. In addition, it compares the sources of supply for cannabis with those found in studies of other European countries. Methods: Analyses are based on data from the Swiss Cannabis Monitoring Study. As part of this longitudinal, representative population survey, more than 5000 adolescents and young adults were interviewed by telephone on the topic of cannabis. Within the total sample, 593 (2004) or 554 (2007) respectively, current cannabis users replied to the questions on sources of supply. Changes in law-enforcement and societal climate concerning cannabis are assessed based on relevant literature, media reports and parliamentary discussions. Results: Whereas 22% of cannabis users stated in 2004 that they bought their cannabis from vendors in hemp shops, this proportion drastically decreased to 6% three years later. At the same time, cannabis was obtained increasingly from friends, while the proportion of users who purchased cannabis from dealers in the alleyway, more than doubled from 6% (2004) to 13% (2007). It was male cannabis users, and in particular, young adult and frequent users, who have moved into the alleyways. Generally, users who buy cannabis in the alleyway show more cannabis-related problems than those who mainly name other sources of supply, even when adjusted for sex, age and frequency of cannabis use. Discussion: Possible consequences of these changes in cannabis supply, like the risk of merging a previously cannabis-only market with other 'harder' drugs markets, are discussed.

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BACKGROUND: Acute treatment of ischemic stroke patients presenting more than eight-hours after symptom onset remains limited and largely unproven. Partial aortic occlusion using the NeuroFlo catheter can augment cerebral perfusion in animals. We investigated the safety and feasibility of employing this novel catheter to treat ischemic stroke patients eight-hours to 24 h following symptom onset. METHODS: A multicenter, single-arm trial enrolled ischemic stroke patients at nine international academic medical centers. Eligibility included age 18-85 years old, National Institutes of Health stroke scale (NIHSS) score between four and 20, within eight-hours to 24 h after symptom onset, and perfusion-diffusion mismatch confirmed by magnetic resonance imaging. The primary outcome was all adverse events occurring from baseline to 30 days posttreatment. Secondary outcomes included stroke severity on neurological indices through 90 days. This study is registered with ClinicalTrials.gov, number NCT00436592. RESULTS: A total of 26 patients were enrolled. Of these, 25 received treatment (one excluded due to aortic morphology); five (20%) died. Favorable neurological outcome at 90 days (modified Rankin score 0-2 vs. 3-6) was associated with lower baseline NIHSS (P < 0·001) and with longer duration from symptom discovery to treatment. There were no symptomatic intracranial hemorrhages or parenchymal hematomas. Asymptomatic intracranial hemorrhage was visible on computed tomography in 32% and only on microbleed in another 20%. CONCLUSIONS: Partial aortic occlusion using the NeuroFlo catheter, a novel collateral therapeutic strategy, appears safe and feasible in stroke patients eight-hours to 24 h after symptom onset.

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A differentiated reconstruction of palaeolimnologic, -environmental, and -climatic conditions is presented for the Middle Miocene long-term freshwater lake (14.3 to 13.5 Ma) of the Steinheim basin, on the basis of a combined C, 0, and Sr isotope study of sympatric skeletal fossils of aquatic and terrestrial organisms from the lake sediments. The oxygen isotope composition for lake water of the Steinheim basin (delta O-18(H2O) = +2.0 +/- 0.4 parts per thousand VSMOW, n = 6) was reconstructed from measurements of delta O-18(PO4) of aquatic turtle bones. The drinking water calculated from the enamel of large mammals (proboscideans, rhinocerotids, equids, cervids, suids) has delta O-18(H2O) values (delta(OH2O)-O-18 = -5.9 +/- 1.7 parts per thousand VSMOW, n = 31) typical for Middle Miocene meteoric water of the area. This delta O-18(H2O) value corresponds to a mean annual air temperature (MAT) of 18.8 +/- 3.8 degrees C, calculated using a modem-day delta(OH2O)-O-18-MAT relation. Hence, large mammals did not use the lake water as principal drinking water. In contrast, small mammals, especially the then abundant pika Prolagus oeningensis drank from O-18-enriched water sources (delta O-18(H2O) = +2.7 +/- 2.3 parts per thousand VSMOW, n = 7), such as the lake water. Differences in Sr and 0 isotopic compositions between large and small mammal teeth indicate different home ranges and drinking behaviour and support migration of some large mammals between the Swabian Alb plateau and the nearby Molasse basin, while small mammals ingested their food and water locally. Changes in the lake level, water chemistry, and temperature were inferred using isotopic compositions of ostracod and gastropod shells from a composite lake sediment profile. Calcitic ostracod valves (Ilyocypris binocularis; delta O-18 = +1.7 +/- 1.2 parts per thousand VPDB, delta C-18 = -0.5 +/- 0.9 parts per thousand, VPDB, n = 68) and aragonitic, gastropod shells (Gyraulus spp.; delta O-18 = +2.0 +/- 13 parts per thousand VPDB, delta C-13 = -1.1 +/- 1.3 parts per thousand VPDB, n = 89) have delta O-18 and delta C-13 values similar to or even higher than those of marine, carbonates. delta C-13 values:of the biogenic carbonates parallel lake level fluctuations while delta O-18 values scatter around +2 +/- 2 parts per thousand and reflect the short term variability of meteoric water inflow vs. longer term evaporation. Sr-87/Sr-86 ratios of aragonitic Gyraulus spp. gastropod shells parallel the lake level fluctuations, reflecting variable inputs of groundwater and surface waters. Using a water delta O-18(H2O) value of +2.0 parts per thousand VSMOW, water temperatures calculated from skeletal tissue delta O-18 values of ostracods are 16.7 +/- 5.0 degrees C, gastropods 20.6 +/- 5.6 degrees C, otoliths 21.8 +/- 1.4 degrees C, and fish teeth 17.0 +/- 2.7 degrees C. The calculated MAT (similar to 19 degrees C), lake water temperatures (similar to 17 to 22 degrees C) and the O-18-enriched water compositions are indicative of warm-temperate climatic conditions, possibly with a high humidity during this period. Vegetation in the area surrounding the basin was largely of the C-3-type, as indicated by carbon isotopic compositions of tooth enamel from large mammals (delta C-13 = -11.1 +/- 1.1 parts per thousand VPDB, n = 40). (c) 2006 Elsevier B.V. All rights reserved.

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We tested the hypothesis that elevation in heart rate (HR) during submaximal exercise in the heat is related, in part, to increased percentage of maximal O(2) uptake (%Vo(2 max)) utilized due to reduced maximal O(2) uptake (Vo(2 max)) measured after exercise under the same thermal conditions. Peak O(2) uptake (Vo(2 peak)), O(2) uptake, and HR during submaximal exercise were measured in 22 male and female runners under four environmental conditions designed to manipulate HR during submaximal exercise and Vo(2 peak). The conditions involved walking for 20 min at approximately 33% of control Vo(2 max) in 25, 35, 40, and 45 degrees C followed immediately by measurement of Vo(2 peak) in the same thermal environment. Vo(2 peak) decreased progressively (3.77 +/- 0.19, 3.61 +/- 0.18, 3.44 +/- 0.17, and 3.13 +/- 0.16 l/min) and HR at the end of the submaximal exercise increased progressively (107 +/- 2, 112 +/- 2, 120 +/- 2, and 137 +/- 2 beats/min) with increasing ambient temperature (T(a)). HR and %Vo(2 peak) increased in an identical fashion with increasing T(a). We conclude that elevation in HR during submaximal exercise in the heat is related, in part, to the increase in %Vo(2 peak) utilized, which is caused by reduced Vo(2 peak) measured during exercise in the heat. At high T(a), the dissociation of HR from %Vo(2 peak) measured after sustained submaximal exercise is less than if Vo(2 max) is assumed to be unchanged during exercise in the heat.

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CONCLUSION: There are several factors that influence the final outcome when treating oral squamous cell carcinoma (OSCC). Invasive front phenomena and more importantly their clinicopathological translation can have a direct impact on survival, and subsequently on the decision for an adjuvant treatment. OBJECTIVES: In recent years, the concept of tumor-host interaction has been the subject of substantial efforts in cancer research. Tumoral behavior may be better understood when studying the changes occurring at the tumor-host interface. This study evaluated the influence of several clinicopathological features on the outcome of OSCCs. METHODS: The clinical records and pathology specimens of 54 patients with OSCC treated by primary resection were reviewed retrospectively. The pathologic features reviewed were: invasive front grading (IFG), stromal reaction, lymphovascular invasion (LVI), perineural invasion (PNI), margin status, and depth of invasion. RESULTS: High IFGs had a significant relationship with pT status and pN status. High IFGs were strongly correlated with nodal metastases (odds ratio (OR) = 4.77; confidence interaval (CI) = 1.37-16.64). Concerning survival, IFG had a strong impact on disease-free survival in patients treated unimodally, as did the depth of invasion in the same group. Lymphovascular involvement was found to have a negative impact on overall survival in patients treated multimodally.

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RESUME En Amérique Centrale et en Amérique du Sud, la leishmaniose cutanéo-muqueuse (LCM) est provoquée par le protozoaire Leishmania du sous-genre Viannia dont font partie L. (V.) braziliensis, L. (V.) panamensis et L. (V.) guyanensis. Dans la LCM, après guérison apparente de la lésion primitive, des lésions secondaires peuvent apparaître dues à la migration de l'infection à partir du site d'inoculation vers les muqueuses de l'ororhino-pharynx. Ce type de dissémination, communément appelé métastase, peut se produire plusieurs années après la guérison de la lésion cutanée initiale, et est un facteur majeur contribuant à la morbidité associée à la LCM. L'expression reproductible de l'activité métastatique au sein de populations discrètes de leishmanies chez le hamster fournit un modèle expérimental permettant d'étudier le degré de virulence du parasite. Nous avons utilisé des clones de L. (V.) guyanensis présentant des phénotypes stables allant d'un caractère hautement métastatique (M+) à non-métastatique (M-) comme outils pour mettre en évidence des facteurs spécifiques liés à la métastase chez les leishmanies du Nouveau Monde. Des analyses protéomiques comparatives utilisant l'électrophorèse bidimensionnelle sur gel de polyacrylamide couplée à de la spectrométrie de masse ont permis l'identification de plusieurs formes de la tryparedoxine peroxidase (TXNPx) en tant que polypeptides associés au phénotype métastatique. TXNPx, une enzyme de la famille des peroxiredoxines (Prxs), protéines antioxydantes, fonctionne comme la dernière peroxydase d'une cascade d'oxydoréductases qui réduit le peroxyde d'hydrogène aux dépens de NADPH. Toutes les Prxs sont caractérisées par un (1-Cys Prx) ou par deux résidus cystéines (2-Cys Prx), respectivement placés dans un environnement structurel conservé de la protéine et sont centrales dans la réaction catalytique. Des immuno-empreintes (« immunoblotting ») ont révélé que TXNPx est présente sous forme dimérique dans les promastigotes (M+) alors que dans les promastigotes, (M-) TXNPx est présente sous forme monomérique et dimérique. Cette caractéristique spécifique de dimérisation pourrait expliquer les différentes activités enzymatiques observées entre les deux promastigotes (M+) et (M-) en présence de peroxyde d'hydrogène ainsi que leur différence de survie et de charge parasitaire à l'intérieur des macrophages. Par conséquent, le processus métastatique pourrait être lié à la capacité du parasite à échapper efficacement aux défenses microbicides de la cellule hôte. ABSTRACT In South and Central America, protozoan parasites of the Leishmania Viannia subgenus including L. (V.) braziliensis, L. (V.) guyanensis and L. (V). panamensis cause mucocutaneous leishmaniasis (MCL). In MCL, after apparent cure of the primary lesion, secondary lesions may appear in the nasopharyngeal tissues of the infected host due to dissemination of the infection from the inoculation site. This type of dissemination, known as metastasis, can occur several years after healing of the original cutaneous lesion, and is a major contributory factor to the morbidity associated with MCL. The reproducible expression of metastasis by discrete populations of Leishmania parasites in hamsters provides an experimental model to examine the expression of parasite virulence. We used laboratory clones of L. (V.) guyanensis with stable phenotypes ranging from highly metastatic (M+) to non-metastatic (M-) as tools for the discovery of specific factors associated with metastasis in New World Leishmania species. Comparative proteome analyses via 2D-electrophoresis (2-DE) coupled with mass spectrometry (MS) enabled the identification of various isoforms of tryparedoxin peroxidase (TXNPx) as polypeptides associated with the metastatic phenotype. TXNPx, an enzyme related to the antioxidant peroxiredoxin family (Prx) functions as the terminal peroxidase of a redox cascade that reduces hydroperoxides by NADPH. All Prxs are characterized by one (1-Cys Prx) or two cysteine residue(s) (2-Cys Prx), respectively, located in a conserved structural environment of the protein which are central for the catalytic reaction. Immunoblotting analysis revealed that, under non-reducing denaturing conditions, TXNPx is present in dimeric forms in (M+) promastigotes, whereas in (M-) promastigotes, both monomeric and dimeric forms are found. This specific dimerization feature may explain the different enzymatic activities of both (M+) and (M-) promastigote parasites in the presence of H2O2 and their difference in survival and parasite load inside macrophages. Therefore, the metastatic process could be related to the ability of the parasite to efficiently evade the microbicidal effect of the host cell.

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Introduction: According to guidelines, patients with coronary artery disease (CAD) should undergo revascularization if myocardial ischemia is present. While coronary angiography (CXA) allows the morphological assessment of CAD, the fractional flow reserve (FFR) has proved to be a complementary invasive test to assess the functional significance of CAD, i.e. to detect ischemia. Perfusion Cardiac Magnetic Resonance (CMR) has turned out to be a robust non-invasive technique to assess myocardial ischemia. The objective: is to compare the cost-effectiveness ratio - defined as the costs per patient correctly diagnosed - of two algorithms used to diagnose hemodynamically significant CAD in relation to the pretest likelihood of CAD: 1) aCMRto assess ischemia before referring positive patients to CXA (CMR + CXA), 2) a CXA in all patients combined with a FFR test in patients with angiographically positive stenoses (CXA + FFR). Methods: The costs, evaluated from the health care system perspective in the Swiss, German, the United Kingdom (UK) and the United States (US) contexts, included public prices of the different tests considered as outpatient procedures, complications' costs and costs induced by diagnosis errors (false negative). The effectiveness criterion wasthe ability to accurately identify apatient with significantCAD.Test performancesused in the model were based on the clinical literature. Using a mathematical model, we compared the cost-effectiveness ratio for both algorithms for hypothetical patient cohorts with different pretest likelihood of CAD. Results: The cost-effectiveness ratio decreased hyperbolically with increasing pretest likelihood of CAD for both strategies. CMR + CXA and CXA + FFR were equally costeffective at a pretest likelihood of CAD of 62% in Switzerland, 67% in Germany, 83% in the UK and 84% in the US with costs of CHF 5'794, Euros 1'472, £ 2'685 and $ 2'126 per patient correctly diagnosed. Below these thresholds, CMR + CXA showed lower costs per patient correctly diagnosed than CXA + FFR. Implications for the health care system/professionals/patients/society These results facilitate decision making for the clinical use of new generations of imaging procedures to detect ischemia. They show to what extent the cost-effectiveness to diagnose CAD depends on the prevalence of the disease.

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Background/Purpose: The primary treatment goals for gouty arthritis (GA) are rapid relief of pain and inflammation during acute attacks, and long-term hyperuricemia management. A post-hoc analysis of 2 pivotal trials was performed to assess efficacy and safety of canakinumab (CAN), a fully human monoclonal anti-IL-1_ antibody, vs triamcinolone acetonide (TA) in GA patients unable to use NSAIDs and colchicine, and who were on stable urate lowering therapy (ULT) or unable to use ULT. Methods: In these 12-week, randomized, multicenter, double-blind, double-dummy, active-controlled studies (_-RELIEVED and _-RELIEVED II), patients had to have frequent attacks (_3 attacks in previous year) meeting preliminary GA ACR 1977 criteria, and were unresponsive, intolerant, or contraindicated to NSAIDs and/or colchicine, and if on ULT, ULT was stable. Patients were randomized during an acute attack to single dose CAN 150 mg s.c. or TA 40 mg i.m. and were redosed "on demand" for each new attack. Patients completing the core studies were enrolled into blinded 12-week extension studies to further investigate on-demand use of CAN vs TA for new attacks. The subpopulation selected for this post-hoc analysis was (a) unable to use NSAIDs and colchicine due to contraindication, intolerance or lack of efficacy for these drugs, and (b) currently on ULT, or contraindication or previous failure of ULT, as determined by investigators. Subpopulation comprised 101 patients (51 CAN; 50 TA) out of 454 total. Results: Several co-morbidities, including hypertension (56%), obesity (56%), diabetes (18%), and ischemic heart disease (13%) were reported in 90% of this subpopulation. Pain intensity (VAS 100 mm scale) was comparable between CAN and TA treatment groups at baseline (least-square [LS] mean 74.6 and 74.4 mm, respectively). A significantly lower pain score was reported with CAN vs TA at 72 hours post dose (1st co-primary endpoint on baseline flare; LS mean, 23.5 vs 33.6 mm; difference _10.2 mm; 95% CI, _19.9, _0.4; P_0.0208 [1-sided]). CAN significantly reduced risk for their first new attacks by 61% vs TA (HR 0.39; 95% CI, 0.17-0.91, P_0.0151 [1-sided]) for the first 12 weeks (2nd co-primary endpoint), and by 61% vs TA (HR 0.39; 95% CI, 0.19-0.79, P_0.0047 [1-sided]) over 24 weeks. Serum urate levels increased for CAN vs TA with mean change from baseline reaching a maximum of _0.7 _ 2.0 vs _0.1 _ 1.8 mg/dL at 8 weeks, and _0.3 _ 2.0 vs _0.2 _ 1.4 mg/dL at end of study (all had GA attack at baseline). Adverse Events (AEs) were reported in 33 (66%) CAN and 24 (47.1%) TA patients. Infections and infestations were the most common AEs, reported in 10 (20%) and 5 (10%) patients treated with CAN and TA respectively. Incidence of SAEs was comparable between CAN (gastritis, gastroenteritis, chronic renal failure) and TA (aortic valve incompetence, cardiomyopathy, aortic stenosis, diarrohea, nausea, vomiting, bicuspid aortic valve) groups (2 [4.0%] vs 2 [3.9%]). Conclusion: CAN provided superior pain relief and reduced risk of new attack in highly-comorbid GA patients unable to use NSAIDs and colchicine, and who were currently on stable ULT or unable to use ULT. The safety profile in this post-hoc subpopulation was consistent with the overall _-RELIEVED and _-RELIEVED II population.

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BACKGROUND: The prevalence of hyperuricemia has rarely been investigated in developing countries. The purpose of the present study was to investigate the prevalence of hyperuricemia and the association between uric acid levels and the various cardiovascular risk factors in a developing country with high average blood pressures (the Seychelles, Indian Ocean, population mainly of African origin). METHODS: This cross-sectional health examination survey was based on a population random sample from the Seychelles. It included 1011 subjects aged 25 to 64 years. Blood pressure (BP), body mass index (BMI), waist circumference, waist-to-hip ratio, total and HDL cholesterol, serum triglycerides and serum uric acid were measured. Data were analyzed using scatterplot smoothing techniques and gender-specific linear regression models. RESULTS: The prevalence of a serum uric acid level >420 micromol/L in men was 35.2% and the prevalence of a serum uric acid level >360 micromol/L was 8.7% in women. Serum uric acid was strongly related to serum triglycerides in men as well as in women (r = 0.73 in men and r = 0.59 in women, p < 0.001). Uric acid levels were also significantly associated but to a lesser degree with age, BMI, blood pressure, alcohol and the use of antihypertensive therapy. In a regression model, triglycerides, age, BMI, antihypertensive therapy and alcohol consumption accounted for about 50% (R2) of the serum uric acid variations in men as well as in women. CONCLUSIONS: This study shows that the prevalence of hyperuricemia can be high in a developing country such as the Seychelles. Besides alcohol consumption and the use of antihypertensive therapy, mainly diuretics, serum uric acid is markedly associated with parameters of the metabolic syndrome, in particular serum triglycerides. Considering the growing incidence of obesity and metabolic syndrome worldwide and the potential link between hyperuricemia and cardiovascular complications, more emphasis should be put on the evolving prevalence of hyperuricemia in developing countries.