378 resultados para Hemodynamics, Intermittent Positive-Pressure Ventilation


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Glucocorticoid hormones are critical to respond and adapt to stress. Genetic variations in the glucocorticoid receptor (GR) gene alter hypothalamic-pituitary-adrenal (HPA) axis activity and associate with hypertension and susceptibility to metabolic disease. Here we test the hypothesis that reduced GR density alters blood pressure and glucose and lipid homeostasis and limits adaption to obesogenic diet. Heterozygous GR βgeo/+ mice were generated from embryonic stem (ES) cells with a gene trap integration of a β-galactosidase-neomycin phosphotransferase (βgeo) cassette into the GR gene creating a transcriptionally inactive GR fusion protein. Although GRβgeo/+ mice have 50% less functional GR, they have normal lipid and glucose homeostasis due to compensatory HPA axis activation but are hypertensive due to activation of the renin-angiotensin- aldosterone system (RAAS). When challenged with a high-fat diet, weight gain, adiposity, and glucose intolerance were similarly increased in control and GRβgeo/+ mice, suggesting preserved control of intermediary metabolism and energy balance. However, whereas a high-fat diet caused HPA activation and increased blood pressure in control mice, these adaptions were attenuated or abolished in GRβgeo/+ mice. Thus, reduced GR density balanced by HPA activation leaves glucocorticoid functions unaffected but mineralocorticoid functions increased, causing hypertension. Importantly, reduced GR limits HPA and blood pressure adaptions to obesogenic diet.

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The 20% ethanol intermittent-access (IAE) two-bottle-choice drinking procedure has been shown to produce high voluntary ethanol consumption in a number of rat strains. For this study, we applied this procedure to male Fischer (F344) rats, a strain previously reported to exhibit low levels of ethanol consumption. We also subjected these animals to a two-week ethanoldeprivation- period to see if they would exhibit an alcohol deprivation effect (ADE) signified by a transient increase in alcohol consumption following deprivation. Our data show a separation between high and low consuming animals within this strain, with high-consumers exhibiting an escalation in consumption. In contrast, Fischer rats did not show a significant separation between high and low consumers or any significant escalation in consumption, using the 20% ethanol continuous-access two-bottle-choice drinking protocol. Following the two-week deprivation period, animals in the high (but not the low) IAE group exhibited the transient increase in ethanol consumption and preference typically associated with an ADE. Together, the data suggest that the intermittent access protocol is a useful protocol for increasing ethanol consumption.

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A descriptive study was undertaken to establish the 95 percentile limits (proposed normal reference range) for pressure beneath the hallux, metatarsal heads, and heel in a group of healthy adult subjects. A new force plate device capable of accurately measuring discrete areas of pressure beneath the human foot with high temporal and spatial resolution was used. The system is capable of accurately measuring plantar foot pressure during dynamic and static foot function. The results of this research are in close agreement with other published studies of plantar foot pressure measurement with comparable systems.

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One of the most significant activities induced by interferon-gamma against intracellular pathogens is the induction of IDO (indoleamine 2,3-dioxygenase) expression, which subsequently results in the depletion of tryptophan. We tested the hypothesis that human strains of Chlamydia pneumoniae are more sensitive to tryptophan limitation than animal C. pneumoniae strains. The human strains were significantly more sensitive to IFN-γ than the animal strains in a lung epithelia cell model (BEAS-2B), with exposure to 1 U ml(-1) IFN-γ resulting in complete loss of infectious yield of human strains, compared to the animal strains where reductions in infectious progeny were around 3.5-4.0 log. Strikingly, the IFN-γ induced loss of ability to form infectious progeny production was completely rescued by removal of the IFN-γ and addition of exogenous tryptophan for the human strains, but not the animal strains. In fact, a human heart strain was more capable of entering a non-infectious, viable persistent stage when exposed to IFN-γ and was also more effectively rescued, compared to a human respiratory strain. Exquisite susceptibility to IFN-γ, specifically due to tryptophan availability appears to be a core adaptation of the human C. pneumoniae strains, which may reflect the chronic nature of their infections in this host.

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Background As financial constraints can be a barrier to accessing HIV antiretroviral therapy (ART), we argue for the removal of copayment requirements from HIV medications in South Australia. Methods Using a simple mathematical model informed by available behavioural and biological data and reflecting the HIV epidemiology in South Australia, we calculated the expected number of new HIV transmissions caused by persons who are not currently on ART compared with transmissions for people on ART. The extra financial investment required to cover the copayments to prevent an HIV infection was compared with the treatment costs saved due to averting HIV infections. Results It was estimated that one HIV infection is prevented per year for every 31.4 persons (median, 24.0–42.7 interquartile range (IQR)) who receive treatment. By considering the incremental change in costs and outcomes of a change in program from the current status quo, it would cost the health sector $17 860 per infection averted (median, $13 651–24 287 IQR) if ART is provided as a three-dose, three-drug combination without requirements for user-pay copayments. Conclusions The costs of removing copayment fees for ART are less than the costs of treating extra HIV infections that would result under current conditions. Removing the copayment requirement for HIV medication would be cost-effective from a governmental perspective.

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This chapter offers three insights into the relationship between curriculum decision making, positive school climate, and academic achievement for same-sex attracted (SSA) students, highlighting the need for students to be offered more than heteronormative narratives and silence on issues of sexuality in the official school curriculum. The authors firstly provide a review of research and report on findings of a doctoral study (Mikulsky, 2007) explaining the impact of SSA students’ perceptions of school climate on their motivation and academic self-concept. Situating the work in the context of the Australian Curriculum for English and associated classroom texts, the dominant discourse of ‘straight, white female’ heroines as exemplified in the globally popular young adult novel The hunger games and other texts popular with Australian students are critiqued, with an argument made for expanding notions of what it means to ‘attend to’ gender and sexuality through textual choice and critical pedagogy. The authors show how texts that feature LGBTQ characters and storylines continue to be marginalized and constructed as taboo and demonstrate how curricular choices can and do impact academic outcomes for marginalized students. Issues of gender and sexuality are framed as a cross-curriculum imperative, with recommendations made for the explicit inclusion of materials exploring gender and sexuality in the official curriculum of all key learning areas.

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The global grown in institutional investors means that firms can no longer ignore their influence in capital markets. However, not all institutional investors have the same motives to influence the firms they invest in. Institution investors' ability to influence management depends on the size of their investment and whether they have any business relations with the firm. Using a sample of Australian firms from 2006 to 2008, our empirical results show that the proportion of a company's shares held by institutional investors is positively associated with firm governance ratings, risk and profitability. This study shows that a positive association between risk and return is associated with large active institutional ownership, which we interpret as shareholders with sufficient power to pressure management to increase short-term profits.

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Millions of people with print disabilities are denied the right to read. While some important efforts have been made to convert standard books to accessible formats and create accessible repositories, these have so far only addressed this crisis in an ad hoc way. This article argues that universally designed ebook libraries have the potential of substantially enabling persons with print disabilities. As a case study of what is possible, we analyse 12 academic ebook libraries to map their levels of accessibility. The positive results from this study indicate that universally designed ebooks are more than possible; they exist. While results are positive, however, we also found that most ebook libraries have some features that frustrate full accessibility, and some ebook libraries present critical barriers for people with disabilities. Based on these findings, we consider that some combination of private pressure and public law is both possible and necessary to advance the right-to-read cause. With access improving and recent advances in international law, now is the time to push for universal design and equality.

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PURPOSE: The prevalence of anaplastic lymphoma kinase (ALK) gene fusion (ALK positivity) in early-stage non-small-cell lung cancer (NSCLC) varies by population examined and detection method used. The Lungscape ALK project was designed to address the prevalence and prognostic impact of ALK positivity in resected lung adenocarcinoma in a primarily European population. METHODS: Analysis of ALK status was performed by immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) in tissue sections of 1,281 patients with adenocarcinoma in the European Thoracic Oncology Platform Lungscape iBiobank. Positive patients were matched with negative patients in a 1:2 ratio, both for IHC and for FISH testing. Testing was performed in 16 participating centers, using the same protocol after passing external quality assessment. RESULTS: Positive ALK IHC staining was present in 80 patients (prevalence of 6.2%; 95% CI, 4.9% to 7.6%). Of these, 28 patients were ALK FISH positive, corresponding to a lower bound for the prevalence of FISH positivity of 2.2%. FISH specificity was 100%, and FISH sensitivity was 35.0% (95% CI, 24.7% to 46.5%), with a sensitivity value of 81.3% (95% CI, 63.6% to 92.8%) for IHC 2+/3+ patients. The hazard of death for FISH-positive patients was lower than for IHC-negative patients (P = .022). Multivariable models, adjusted for patient, tumor, and treatment characteristics, and matched cohort analysis confirmed that ALK FISH positivity is a predictor for better overall survival (OS). CONCLUSION: In this large cohort of surgically resected lung adenocarcinomas, the prevalence of ALK positivity was 6.2% using IHC and at least 2.2% using FISH. A screening strategy based on IHC or H-score could be envisaged. ALK positivity (by either IHC or FISH) was related to better OS.

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Complex behaviour of air flow in the buildings makes it difficult to predict. Consequently, architects use common strategies for designing buildings with adequate natural ventilation. However, each climate needs specific strategies and there are not many heuristics for subtropical climate in literature. Furthermore, most of these common strategies are based on low-rise buildings and their performance for high-rise buildings might be different due to the increase of the wind speed with increase in the height. This study uses Computational Fluid Dynamics (CFD) to evaluate these rules of thumb for natural ventilation for multi-residential buildings in subtropical climate. Four design proposals for multi-residential towers with natural ventilation which were produced in intensive two days charrette were evaluated using CFD. The results show that all the buildings reach acceptable level of wind speed in living areas and poor amount of air flow in sleeping areas.

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BACKGROUND: Magnetic resonance imaging (MRI) is being increasingly utilized to define pathology and guide treatment in patients presenting with wrist pain. The clinical relevance of MRI identified or confirmed pathology has not been established, and the prevalence of asymptomatic MRI pathology is not known. METHODS: Twenty volunteers with no previous wrist injury or symptoms underwent bilateral MRI wrist studies in this exploratory diagnostic study. The scans were reported by an experienced musculoskeletal radiologist and an experienced wrist surgeon, with a consensus reached on each report. RESULTS: There were 3.15 positive MRI findings per wrist. There were 126 positive findings (range 1-6 per wrist). Sixty-eight ganglia were identified. Eleven ligament tears or perforations were also identified. Increased joint fluid was seen at many sites, most frequently adjacent to the piso-triquetral joint. CONCLUSION: The accuracy of MRI in identifying triangular fibrocartilage complex tears, intercarpal ligament tears and carpal bone osteonecrosis is rapidly being refined. Positive MRI findings are common and may be coincidental in patients with wrist pain. MRI findings need to be correlated closely with clinical examination and history.

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Considered a condition of the elderly population, stroke will soon be the leading cause of death globally. In Singapore it is the fourth leading cause of death after cancer and heart disease. Subarachnoid haemorrhage, when compared with an embolic stroke, has a more devastating outcome because of the deleterious complications associated with it. Vasospam, re-bleeding and global cerebral ischemia are three of the most prominent complications. Therefore, nursing care and interventions developed to reduce the incidence of complications and optimise neurological function are critical in the acute phase of this condition. Using a casestudy approach this article will discuss and offer a rationale to a number of key nursing interventions based around a nursing care plan designed to reduce the incidence of complications.