940 resultados para Lack of land


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The area of private land suitable and available for growing hoop pine (Araucaria cunninghamii) on the Atherton Tablelands in North Queensland was modelled using a geographic information system (GIS). In Atherton, Eacham and Herberton shires, approximately 64,700 ha of privately owned land were identified as having a mean annual rainfall and soil type similar to Forestry Plantations Queensland (FPQ) hoop pine growth plots with an approximate growth rate of 20 m3 per annum. Land with slope of over 25° and land covered with native vegetation were excluded in the estimation. If land which is currently used for high-value agriculture is also excluded, the net area of land potentially suitable and available for expansion of hoop pine plantations is approximately 22,900 ha. Expert silvicultural advice emphasized the role of site preparation and weed control in affecting the long-term growth rate of hoop pine. Hence, sites with less than optimal fertility and rainfall may be considered as being potentially suitable for growing hoop pine at a lower growth rate. The datasets had been prepared at various scales and differing precision for their description of land attributes. Therefore, the results of this investigation have limited applicability for planning at the individual farm level but are useful at the regional level to target areas for plantation expansion.

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Galectin-3 is a p-galactoside-binding lectin implicated in the fine-tuning of innate immunity. Rhodococcus equi, a facultative intracellular bacterium of macrophages, causes severe granulomatous bronchopneumonia in young horses and immunocompromised humans. The aim of this study is to investigate the role of galectin-3 in the innate resistance mechanism against R. equi infection. The bacterial challenge of galectin-3-deficient mice (gal3(-/-)) and their wild-type counterpart (gal3(+/+)) revealed that the LD50 for the gal3(-/-) mice was about seven times higher than that for the gal3(+/+) mice. When challenged with a sublethal dose, gal3(-/-) mice showed lower bacteria counts and higher production of IL-12 and IFN-gamma production, besides exhibiting a delayed although increased inflammatory reaction. Gal3(-/-) macrophages exhibited a decreased frequency of bacterial replication and survival, and higher transcript levels of IL-1 beta, IL-6, IL-10, TLR2 and MyD88. R. equi-infected gal3(+/+) macrophages showed decreased expression of TLR2, whereas R. equi-infected gal3(-/-) macrophages showed enhanced expression of this receptor. Furthermore, galectin-3 deficiency in macrophages may be responsible for the higher IL-1 beta serum levels detected in infected gal3(-/-) mice. Therefore galectin-3 may exert a regulatory role in innate immunity by diminishing IL-1 beta production and thus affecting resistance to R. equi infection.

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T-cell proliferative hypo responsiveness, a hallmark of paracoccidioidomycosis immune responses, underlies host`s failure in controlling fungus spread, being reversible with antifungal treatment. The mechanisms leading to this hypoproliferation are not well known. Since costimulatory molecules have been shown to profoundly regulate T-cell immune responses, we investigated the hypothesis that the determinants of the responder versus tolerant state may be the regulated expression of, or signaling by, costimulatory molecules. Expression of CD80, CD86, CD28, CD152, ICOS and PD-1 costimulatory molecules were examined on T-cells and monocytes harvested from stimulated and unstimulated PBMC cultures of active paracoccidioidomycosis patients and healthy individuals cured of past paracoccidioidomycosis. Stimuli were gp43, the immunodominant component of Paracoccidioides brasiliensis, and a Candida antigen. While CD28 expression, critical for optimal T-cell activation, was comparable between patients and controls, CD152, PD-1 and ICOS, which preferentially deliver negative signaling, were overexpressed on patients` stimulated and unstimutated T-cells. PBMC cultures were carried out in presence of the respective blocking antibodies which, however, failed to restore T-cell proliferation. CD80 and CD86 were equally expressed on patients` and controls` monocytes, but overexpressed on patients` T-cells. Blockade with the respective blocking antibodies on day 4 of the culture also did not restore T-cell proliferation, while, on day 0, differentially inhibited Candida and gp43 responses, suggesting that different antigens require different costimulatory pathways for antigen presentation. Our data favors the hypothesis, raised from other foreign antigen models, that prolonged in vivo antigen exposure leads to an adaptive tolerance T-cell state which is hardly reverted in vitro. (C) 2008 Elsevier Inc. All rights reserved.

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To describe the effect of active surveillance to control vancomycin-resistant enterococci (VRE) after an outbreak, 549 surveillance rectal cultures were performed in 308 patients (35% positive). An educational intervention to prevent transmission was implemented. Infection and colonization by VR-Enterococcus faecalis decreased, but Enterococcus faecium persisted despite control measures. Infections by VR-E faecalis fell to zero in 2008. We observed difficulties in controlling colonization with measures directed mainly by surveillance cultures and differences between responses of E faecium and E faecalis.

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Background. Some neuroimaging studies have supported the hypothesis of progressive brain changes after a first episode of psychosis. We aimed to determine whether (i) first-episode psychosis patients would exhibit more pronounced brain volumetric changes than controls over time and (ii) illness course/treatment would relate to those changes. Method. Longitudinal regional grey matter volume and ventricle : brain ratio differences between 39 patients with first-episode psychosis (including schizophrenia and schizophreniform disorder) and 52 non-psychotic controls enrolled in a population-based case-control study. Results. While there was no longitudinal difference in ventricle : brain ratios between first-episode psychosis subjects and controls, patients exhibited grey matter volume changes, indicating a reversible course in the superior temporal cortex and hippocampus compared with controls. A remitting course was related to reversal of baseline temporal grey matter deficits. Conclusions. Our findings do not support the hypothesis of brain changes indicating a progressive course in the initial phase of psychosis. Rather, some brain volume abnormalities may be reversible, possibly associated with a better illness course.

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Objective: To investigate a possible association between a 3`UTR VNTR polymorphism of the dopamine transporter gene (SLC6A3) and ADHD in a Brazilian sample of adult patients. Method: Study Case-control with 102 ADHD adult outpatients (DSM-IV criteria) and 479 healthy controls. The primers` sequence used were: 3`UTR-Forward: 5`TGT GGT GAT GGG AAC GGC CTG AG 3` and 3`UTR-Reverse: 5`CTT CCT GGA GGT CAC GGC TCA AGG 3`. Alleles of the 3`UTR were coded according to their number of repeats: 6- repeat 320 bp (allele 6), 8- repeat 400 bp (allele 8), 9-repeat 480 bp (allele 9), 10- repeat 480 bp (allele 10), and 11- repeat 520 bp (allele 11). Results: There were no allelic (chi(2) = 2.67, 5df, p = .75) and genotypic (chi(2) = 7.20, 1df, p = .61) association between adult ADHD and VNTR 3`UTR polymorphism of SLC6A3. Conclusion: Our findings do not support SLC6A3 as marker genetic susceptibility factor in adult ADHD. More comprehensive polymorphism coverage within the SLC6A3 region should be conducted in larger samples, including comparisons in clinical subgroups, and in samples with different ethnic backgrounds. (J. of Att. Dis. 2011; 15(4) 305-309)

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Arterial stiffness is an independent marker of cardiovascular events. Pulse wave velocity (PWV) is a validated method to detect arterial stiffness that can be influenced by several factors including age and blood pressure. However, it is not clear whether PWV could be influenced by circadian variations. In the present study, the authors measured blood pressure and carotid-femoral PWV measurements in 15 young healthy volunteers in 4 distinct periods: 8 am, noon, 4 pm, and 8 pm. No significant variations of systolic (P=.92), mean (P=.77), and diastolic (P=.66) blood pressure among 8 am (113 +/- 15, 84 +/- 8, 69 +/- 6 mm Hg), noon (114 +/- 13, 83 +/- 8, 68 +/- 6 mm Hg), 4 pm (114 +/- 13, 85 +/- 8, 70 +/- 7 mm Hg), and 8 pm (113 +/- 7, 83 +/- 10, 68 +/- 7 mm Hg), respectively, were observed. Similarly, carotid-femoral PWV did not change among the periods (8 am: 7.6 +/- 1.4 m/s, noon: 7.4 +/- 1.1 m/s, 4 pm: 7.6 +/- 1.0 m/s, 8 pm, 7.6 +/- 1.3 m/s; P=.85). Considering all measurements, mean blood pressure significantly correlated with PWV (r=.31; P=.016). In young healthy volunteers, there is no significant circadian variation of carotid-femoral PWV. These findings support the concept that it does not appear mandatory to perform PWV measurements at exactly the same period of the day. J Clin Hypertens (Greenwich). 2011;13:19-22. (c) 2010 Wiley Periodicals, Inc.

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Although there is no consensus about the use of glucose and thiamine for the treatment of acute ethanol intoxication, this is a routine practice in many countries. Our objective was to determine the efficacy of this treatment and the changes it causes in the antioxidant status of the liver. Male Wistar rats were intoxicated with an ethanol dose of 5 g/kg and divided into three groups: ethanol (EtOH; untreated), EtOH+G (treated with glucose), and EtOH+B1 (treated with thiamine). Blood and urinary ethanol as well as hepatic malondialdehyde, reduced glutathione and vitamin E were determined in all animals. Blood alcohol levels did not differ between groups, although urinary excretion was about four times higher in the group treated with thiamine (EtOH+B1). The malondialdehyde, reduced glutathione and vitamin E values used here as parameters of the antioxidant system of the liver showed improvement for the thiamine-treated group (EtOH+B1). Treatment with glucose or thiamine was ineffective in reducing blood alcohol levels in rats with acute ethanol intoxication. However, the beneficial effect of thiamine as an antioxidant for ethanol metabolism was demonstrated. Further investigations are necessary to clarify the urinary excretion of ethanol reported here for the first time and the possibility of using thiamine as an antioxidant in situations of chronic alcohol use.

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Background The mechanism underlying increased perception of food bolus passage in the absence of esophageal mechanical obstruction has not been completely elucidated. A correlation between the intensity of the symptom and the severity of esophageal dysfunction, either motility (manometry) or bolus transit (impedance) has not been clearly demonstrated. The aim of this study was to analyze the correlation between objective esophageal function assessment (with manometry and impedance) and perception of bolus passage in healthy volunteers (HV) with normal and pharmacologically-induced esophageal hypocontractility, and in patients with gastro-esophageal reflux disease (GERD) with and without ineffective esophageal motility (IEM). Methods Combined manometry-impedance was performed in 10 HV, 19 GERD patients without IEM and nine patients with IEM. Additionally, nine HV were studied after 50 mg sildenafil, which induced esophageal peristaltic failure. Perception of each 5 mL viscous swallow was evaluated using a 5-point scale. Manometry identified hypocontractility (contractions lower than 30 mmHg) and impedance identified incomplete bolus clearance. Key Results In HV and in GERD patients with and without IEM, there was no association between either manometry or impedance and perception on per swallow analysis (OR: 0.842 and OR: 2.017, respectively), as well as on per subject analysis (P = 0.44 and P = 0.16, respectively). Lack of correlation was also found in HV with esophageal hypocontractility induced by sildenafil. Conclusions & Inferences There is no agreement between objective measurements of esophageal function and subjective perception of bolus passage. These results suggest that increased bolus passage perception in patients without mechanical obstruction might be due to esophageal hypersensitivity.

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Lack of effects of clomipramine on Fos and NADPH-diaphorase double-staining in the periaqueductal gray after exposure to an innate fear stimulus - nitric oxide (NO) acts as a neurotransmitter in the rat dorsolateral periaqueductal gray (dIPAG), a midbrain structure that modulates fear and defensive behavior. Since defensive reactions can be alleviated by anxiolytic/anti-panic drugs, the present study tested the effect of clomipramine, a serotonin re-uptake inhibitor, on the activation of NO-producing neurons in the dlPAG of rats exposed to a live predator. Double staining was performed using Fos immunohistochemistry and NADPH-diaphorase as techniques to mark neural activation and to detect NO-producing neurons, respectively. Male Wistar rats received acute or chronic (21 days) injections of saline or clomipramine (10 or 20 mg/kg/day) and were exposed to a live cat. The animals exhibited a robust defensive reaction accompanied by an increase in the number of Fos- and doublestained neurons in the dlPAG, suggesting that cat exposure activates NO-producing neurons. Such effects were not significantly attenuated by clomipramine treatments. The intensity of fear reaction correlated with the intensity of neural staining in the dlPAG, regardless the drug treatment. Thus, the present results reinforce the hypothesis that NO may coordinate defensive responses in the dIPAG and indicate that this mechanism may not be modulated by a serotonin re-uptake inhibitor. (C) 2008 Elsevier Inc. All rights reserved.

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Fluoride in drinking water may be present from natural sources or added as sodium fluoride (NaF), sodium silicofluoride (Na2SiF6) or fluorosilicic acid (H2SiF6). Results from an early study with rats suggested that, when ingested as Na2SiF6, the absorption and excretion of fluoride were greater than when ingested as NaF. Objective: The present single-blind, crossover study with 10 adults was done to determine three key pharmacokinetic parameters: the maximum plasma fluoride concentrations (C-max), the elapsed time to reach the maximum concentrations (T-max) and the 6-h areas under the time-plasma concentration curves (AUCs) after ingestion of 500 ml, of water containing 0.67 or 5.45 mg F/L present naturally or added as NaF or H2SiF6. Design: Blood was collected prior to and at nine time points during 6 h after ingestion of the test solutions. Plasma was analysed by electrode after HMDS-facilitated diffusion and the data were analysed for statistically significant differences using repeated measures ANOVA. Results: The C-max, T-max and AUC values after ingestion of the solutions containing natural fluoride, NaF or H2SiF6 did not differ significantly at either dose level. Further, the Tmax values associated with the 0.67 and SAS mg/L solutions did not differ significantly indicating that the absorption, distribution and elimination rates were not affected by the dose size. Conclusions: Considered together with published reports, the present findings support the conclusion that the major features of fluoride metabolism are not affected differently by the chemical compounds commonly used to fluoridate water nor are they affected by whether the fluoride is present naturally or added artificially. (C) 2008 Elsevier Ltd. All rights reserved.

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This paper assesses the capacity of local communities and sub-national governments to influence patterns of tourism development, within the context of a globalizing economy. Through a comparison of the contrasting examples of Hawaii and Queensland, the paper indicates the consequences of different approaches to land use regulation. It points to the importance of planning and policy processes that integrate community interests, in order to achieve long-term, sustainable tourism development. Effective regulation of development can minimize the social and environmental impacts of tourism. The paper illustrates how community organizations and sub-national governments can articulate local interests, despite the global demands of investors for more deregulated markets in land.