971 resultados para BETA-D-GLUCOSIDASE


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The building sector is the dominant consumer of energy and therefore a major contributor to anthropomorphic climate change. The rapid generation of photorealistic, 3D environment models with incorporated surface temperature data has the potential to improve thermographic monitoring of building energy efficiency. In pursuit of this goal, we propose a system which combines a range sensor with a thermal-infrared camera. Our proposed system can generate dense 3D models of environments with both appearance and temperature information, and is the first such system to be developed using a low-cost RGB-D camera. The proposed pipeline processes depth maps successively, forming an ongoing pose estimate of the depth camera and optimizing a voxel occupancy map. Voxels are assigned 4 channels representing estimates of their true RGB and thermal-infrared intensity values. Poses corresponding to each RGB and thermal-infrared image are estimated through a combination of timestamp-based interpolation and a pre-determined knowledge of the extrinsic calibration of the system. Raycasting is then used to color the voxels to represent both visual appearance using RGB, and an estimate of the surface temperature. The output of the system is a dense 3D model which can simultaneously represent both RGB and thermal-infrared data using one of two alternative representation schemes. Experimental results demonstrate that the system is capable of accurately mapping difficult environments, even in complete darkness.

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Objective: To compare proteins related to Alzheimer disease ( AD) in the frontal cortex and cerebellum of subjects with early-onset AD (EOAD) with or without presenilin 1 (PS1) mutations with sporadic late-onset AD ( LOAD) and nondemented control subjects. Methods: Immunohistochemistry, immunoblot analysis, and ELISA were used to detect and assess protein levels in brain. Results: In EOAD and to a lesser extent in LOAD, there was increased amyloid beta (Abeta) deposition (by immunohistochemistry), increased soluble Abeta (by immunoblot analysis), and specific increases in Abeta(40) and Abeta(42) ( by ELISA) in the frontal cortex and, in some cases, in the cerebellum. Surprisingly, immunoblot analysis revealed reduced levels of PS1 in many of the subjects with EOAD with or without PS1 mutations. In those PS1 mutation-bearing subjects with the highest Abeta, PS1 was barely, if at all, detectable. This decrease in PS1 was specific and not attributable solely to neuronal loss because amyloid precursor protein (APP) and the PS1-interacting protein beta-catenin levels were unchanged. Conclusions: This study shows that in the frontal cortex and cerebellum from Alzheimer disease patients harboring certain presenilin 1 mutations, high levels of amyloid beta are associated with low levels of presenilin 1. The study provides the premise for further investigation of mechanisms underlying the downregulation of presenilin 1, which may have considerable pathogenic and therapeutic relevance.

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Purpose – This paper adds to growing research of psychiatric intensive care units (PICU) by recounting descriptions of psychiatric intensive care settings and discusses the perceptions held by nurses of the organisational interfaces, arrangements and provisions of care in these settings. Design/methodology/approach – Data gathered from focus groups held with nurses from two PICUs was used to establish terminology, defining attributes, related concepts, antecedents, values, processes and concepts related to current practices. A literature search was conducted to permit a review of the conceptual arrangements and contemporary understanding of intensive care for people experiencing acute psychiatric illness based on the perspectives held by the nurses from the focus groups. Findings – Dissonance between service needs and the needs and management of individual patients overshadow strategies to implement comprehensive recovery-oriented approaches. Three factors are reported in this paper that influence standards and procedural practice in PICU; organisational structures; physical structures; and subtype nomenclature. Practical implications – Acute inpatient care is an important part of a comprehensive approach to mental health services. Commonly intensive acute care is delivered in specialised wards or units co-located with acute mental health inpatient units mostly known as PICU. Evidence of the most effective treatment and approaches in intensive care settings that support comprehensive recovery for improved outcomes is nascent. Originality/value – Current descriptions from nurses substantiate wide variations in the provisions, design and classifications of psychiatric intensive care. Idiosyncratic and localised conceptions of psychiatric intensive care are not adequately entailing effective treatment and methods in support of recovery principles for improved and comprehensive outcomes. The authors suggest that more concrete descriptions, guidelines, training and policies for provision of intensive psychiatric health care encompassing the perspective of nursing professionals, would reinforce conceptual construction and thus optimum treatments within a comprehensive, recovery-oriented approach to mental health services.

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Critical literacy (CL) has been the subject of much debate in the Australian public and education arenas since 2002. Recently, this debate has dissipated as literacy education agendas and attendant policies shift to embrace more hybrid models and approaches to the teaching of senior English. This paper/presentation reports on the views expressed by four teachers of senior English about critical literacy and it’s relevance to students who are from culturally and linguistically diverse backgrounds who are learning English while undertaking senior studies in high school. Teachers’ understandings of critical literacy are important, esp. given the emphasis on Critical and Creative Thinking and Literacy as two of the General Capabilities underpinning the Australian national curriculum. Using critical discourse analysis, data from four specialist ESL teachers in two different schools were analysed for the ways in which these teachers construct critical literacy. While all four teachers indicated significant commitment to critical literacy as an approach to English language teaching, the understandings they articulated varied from providing forms of access to powerful genres, to rationalist approaches to interrogating text, to a type of ‘critical-aesthetic’ analysis of text construction. Implications are also discussed.

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Teaching English to EAL/D learners as a cross-curricula priority, not just the purview of the English classroom or language specialist, is now officially endorsed in the national curriculum. Yet many teachers, including subject English teachers, feel ill-equipped for this task. This paper presents an action research project conducted with a teacher of junior secondary English and Geography. The focus of the project was developing metacognitive reading strategies among EAL/D learners to enable them to access content area information more effectively and more independently. We discuss the particular strategies that were beneficial for students at the Emerging level of English and present a range of research-based reading strategies that teachers can embed in regular teaching in order to enhance reading comprehension. Examples from Geography and English lessons will be provided to show how the teaching of explicit ‘second language’ reading strategies can position EAL/D learners as valuable members of the classroom.

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BACKGROUND & AIMS Metabolomics is comprehensive analysis of low-molecular-weight endogenous metabolites in a biological sample. It could enable mapping of perturbations of early biochemical changes in diseases and hence provide an opportunity to develop predictive biomarkers that could provide valuable insights into the mechanisms of diseases. The aim of this study was to elucidate the changes in endogenous metabolites and to phenotype the metabolic profiling of d-galactosamine (GalN)-inducing acute hepatitis in rats by UPLC-ESI MS. METHODS The systemic biochemical actions of GalN administration (ip, 400 mg/kg) have been investigated in male wistar rats using conventional clinical chemistry, liver histopathology and metabolomic analysis of UPLC- ESI MS of urine. The urine was collected predose (-24 to 0 h) and 0-24, 24-48, 48-72, 72-96 h post-dose. Mass spectrometry of the urine was analysed visually and via conjunction with multivariate data analysis. RESULTS Results demonstrated that there was a time-dependent biochemical effect of GalN dosed on the levels of a range of low-molecular-weight metabolites in urine, which was correlated with developing phase of the GalN-inducing acute hepatitis. Urinary excretion of beta-hydroxybutanoic acid and citric acid was decreased following GalN dosing, whereas that of glycocholic acid, indole-3-acetic acid, sphinganine, n-acetyl-l-phenylalanine, cholic acid and creatinine excretion was increased, which suggests that several key metabolic pathways such as energy metabolism, lipid metabolism and amino acid metabolism were perturbed by GalN. CONCLUSION This metabolomic investigation demonstrates that this robust non-invasive tool offers insight into the metabolic states of diseases.

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Dr Wyatt’s study investigated the complex relationship between vitamin D and melanoma, specifically if vitamin D status is associated with more aggressive melanomas. Exposure to solar ultraviolet radiation is the principal risk factor for melanoma and also the main source of vitamin D. This research found that insufficient vitamin D at time of melanoma diagnosis is significantly associated with poorer prognosis (as defined by tumour thickness). These results will contribute to a more refined public health message concerning melanoma and vitamin D, particularly in Queensland, which has the highest global incidence of melanoma, but vitamin D deficiency is not uncommon.

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Saccharification of sugarcane bagasse pretreated at the pilot-scale with different processes (in combination with steam-explosion) was evaluated. Maximum glucan conversion with Celluclast 1.5 L (15–25 FPU/g glucan) was in the following order: glycerol/HCl > HCl > H2SO4 > NaOH, with the glycerol system achieving ∼100% conversion. Surprisingly, the NaOH substrate achieved optimum saccharification with only 8 FPU/g glucan. Glucan conversions (3.6–6%) obtained with mixtures of endo-1,4-β-glucanase (EG) and β-glucosidase (βG) for the NaOH substrate were 2–6 times that of acid substrates. However, glucan conversions (15–60%) obtained with mixtures of cellobiohydrolase (CBH I) and βG on acidified glycerol substrate were 10–30% higher than those obtained for NaOH and acid substrates. The susceptibility of the substrates to enzymatic saccharification was explained by their physical and chemical attributes. Acidified glycerol pretreatment offers the opportunity to simplify the complexity of enzyme mixtures required for saccharification of lignocellulosics.

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The calcium-activated potassium ion channel gene (KCNN3) is located in the vicinity of the familial hemiplegic migraine type 2 locus on chromosome 1q21.3. This gene is expressed in the central nervous system and plays a role in neural excitability. Previous association studies have provided some, although not conclusive, evidence for involvement of this gene in migraine susceptibility. To elucidate KCNN3 involvement in migraine, we performed gene-wide SNP genotyping in a high-risk genetic isolate from Norfolk Island, a population descended from a small number of eighteenth century Isle of Man ‘Bounty Mutineer’ and Tahitian founders. Phenotype information was available for 377 individuals who are related through the single, well-defined Norfolk pedigree (96 were affected: 64 MA, 32 MO). A total of 85 SNPs spanning the KCNN3 gene were genotyped in a sub-sample of 285 related individuals (76 affected), all core members of the extensive Norfolk Island ‘Bounty Mutineer’ genealogy. All genotyping was performed using the Illumina BeadArray platform. The analysis was performed using the statistical program SOLAR v4.0.6 assuming an additive model of allelic effect adjusted for the effects of age and sex. Haplotype analysis was undertaken using the program HAPLOVIEW v4.0. A total of four intronic SNPs in the KCNN3 gene displayed significant association (P < 0.05) with migraine. Two SNPs, rs73532286 and rs6426929, separated by approximately 0.1 kb, displayed complete LD (r 2 = 1.00, D′ = 1.00, D′ 95% CI = 0.96–1.00). In all cases, the minor allele led to a decrease in migraine risk (beta coefficient = 0.286–0.315), suggesting that common gene variants confer an increased risk of migraine in the Norfolk pedigree. This effect may be explained by founder effect in this genetic isolate. This study provides evidence for association of variants in the KCNN3 ion channel gene with migraine susceptibility in the Norfolk genetic isolate with the rarer allelic variants conferring a possible protective role. This the first comprehensive analysis of this potential candidate gene in migraine and also the first study that has utilised the unique Norfolk Island large pedigree isolate to implicate a specific migraine gene. Studies of additional variants in KCNN3 in the Norfolk pedigree are now required (e.g. polyglutamine variants) and further analyses in other population data sets are required to clarify the association of the KCNN3 gene and migraine risk in the general outbred population.

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Multiple sclerosis (MS) is a common cause of neurological disability in young adults. The disease generally manifests in early to middle adulthood and causes various neurological deficits. Autoreactive T lymphocytes and their associated antigens have long been presumed important features of MS pathogenesis. The Protein tyrosine phosphatase receptor type C gene (PTPRC) encodes the T-cell receptor CD45. Variations within PTPRC have been previously associated with diseases of autoimmune origin such as type 1 diabetes mellitus and Graves' disease. We set out to investigate two variants within the PTPRC gene, C77G and C772T in subjects with MS and matched healthy controls to determine whether significant differences exist in these markers in an Australian population. We employed high resolution melt analysis (HRM) and restriction length polymorphism (RFLP) techniques to determine genotypic and allelic frequencies. Our study found no significant difference between frequencies for PTPRC C77G by either genotype (Χ2 = 0.65, P = 0.72) or allele (Χ2 = 0.48, P = 0.49). Similarly, we did not find evidence to suggest an association between PTPRC C772T by genotype (Χ2 = 1.06, P = 0.59) or allele (Χ2 = 0.20, P = 0.66). Linkage disequilibrium (LD) analysis showed strong linkage disequilibrium between the two tested markers (D' = 0.9970, SD = 0.0385). This study reveals no evidence to suggest that these markers are associated with MS in the tested Australian Caucasian population. Although the PTPRC gene has a significant role in regulating CD4+ and CD8+ autoreactive T-cells, interferon-beta responsiveness, and potentially other important processes, our study does not support a role for the two tested variants of this gene in MS susceptibility in the Australian population.

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Migraine is a debilitating neurological disorder, affecting 12% of Caucasian populations. It is well known that migraine has a strong genetic component, although the type and number of genes involved is unclear. Our previous work has investigated dopamine related migraine candidate genes and has reported a significant allelic association with migraine of a microsatellite localised to the promoter region of the dopamine beta-hydroxylase (DBH) gene. The present study performed an association analysis in a larger population of case-controls (275 unrelated Caucasian migraineurs versus 275 controls) examining two different genetic DBH polymorphisms (a functional insertion/deletion promoter and a coding SNP A444G polymorphism). Although no significant association was found for the SNP polymorphism, the results showed a significant association between the insertion/deletion variant and disease (chi(2)=8.92, P=0.011), in particular in migraine with aura (chi(2)=11.53, P=0.003) compared to the control group. Furthermore, the analysis of this polymorphism stratified by gender, revealed that male individuals with the homozygote deletion genotype had three times the risk of developing migraine, compared to females. The DBH insertion/deletion polymorphism is in linkage disequilibrium with the previously reported migraine associated DBH microsatellite and this insertion/deletion polymorphism is functional, which may explain a potential role in susceptibility to migraine.

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Previous studies in our laboratory have shown association of nuclear receptor expression and histological breast cancer grade. To further investigate these findings, it was the objective of this study to determine if expression levels of the estrogen alpha, estrogen beta and androgen nuclear receptor genes varied in different breast cancer grades. RNA extracted from paraffin embedded archival breast tumour tissue was converted into cDNA and cDNA underwent PCR to enable quantitation of mRNA expression. Expression data was normalised against the 18S ribosomal gene multiplex and analysed using ANOVA. Analysis indicated a significant alteration of expression for the androgen receptor in different cancer grades (P=0.014), as well as in tissues that no longer possess estrogen receptor alpha proteins (P=0.025). However, expression of estrogen receptors alpha and beta did not vary significantly with cancer grade (P=0.057 and 0.622, respectively). Also, the expression of estrogen receptor alpha or beta did not change, regardless of the presence of estrogen receptor alpha protein in the tissue (P=0.794 and 0.716, respectively). Post-hoc tests indicate that the expression of the androgen receptor is increased in estrogen receptor negative tissue as well as in grade 2 and grade 3 tumours, compared to control tissue. This increased expression in late stage breast tumours may have implications to the treatment of breast tumours, particularly those lacking expression of other nuclear receptor genes.

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Multiple Sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS) resulting in accumulating neurological disability. The disorder is more prevalent at higher latitudes. To investigate VDR gene variation using three intragenic restriction fragment length polymorphisms (Apa I, Taq I and Fok I) in an Australian MS case-control population. One hundred and four Australian MS patients were studied with patients classified clinically as Relapsing Remitting MS (RR-MS), Secondary Progressive MS (SP-MS) or Primary Progressive MS (PP-MS). Also, 104 age-, sex-, and ethnicity-matched controls were investigated as a comparative group. Our results show a significant difference of genotype distribution frequency between the case and control groups for the functional exon 9 VDR marker Taq I (p(Gen) = 0.016) and interestingly, a stronger difference for the allelic frequency (p(All) = 0.0072). The Apa I alleles were also found to be associated with MS (p(All) = 0.04) but genotype frequencies were not significantly different from controls (p(Gen) = 0.1). The Taq and Apa variants are in very strong and significant linkage disequilibrium (D' = 0.96, P < 0.0001). The genotypic associations are strongest for the progressive forms of MS (SP-MS and PP-MS). Our results support a role for the VDR gene increasing the risk of developing multiple sclerosis, particularly the progressive clinical subtypes of MS.

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Breast cancer is the leading cause of cancer death among Australian women and its incidence is annually increasing. Genetic factors are involved in the complex etiology of breast cancer. The seco-steroid hormone, 1.25 dihydroxy vitamin D3 can influence breast cancer cell growth in vitro. A number of studies have reported correlations between vitamin D receptor (VDR) gene polymorphisms and several diseases including prostate cancer and osteoporosis. In breast cancer, low vitamin D levels in serum are correlated with disease progression and bone metastases, a situation also noted in prostate cancer and suggesting the involvement of the VDR. In our study, 2 restriction fragment length polymorphisms (RFLP) in the 3' region (detected by Apa1 and Taq1) and an initiation codon variant in the 5' end of the VDR gene (detected by Fok1) were tested for association with breast cancer risk in 135 females with sporadic breast cancer and 110 cancer-free female controls. Allele frequencies of the 3' Apa1 polymorphism showed a significant association (p = 0.016; OR = 1.56, 95% CI = 1.09-2.24) while the Taq1 RFLP showed a similar trend (p = 0.053; OR = 1.45, 95% CI = 1.00-2.00). Allele frequencies of the Fok1 polymorphism were not significantly different (p = 0.97; OR = 0.99, 95% CI = 0.69-1.43) in the study population. Our results suggest that specific alleles of the VDR gene located near the 3' region may identify an increased risk for breast cancer and justify further investigation of the role of VDR in breast cancer.