36 resultados para Education, Finance|Education, Administration|Education, Adult and Continuing
Resumo:
Modulation of the cytochrome P450 (CYP) monooxygenase system by cadmium was investigated in male, adult DBA/2J mice treated with a single dose (16 Amol/kg body weight, i.p.) of cadmium chloride (CdCl2) at various time points. The total CYP content of kidney microsomes started to decrease 4 hours earlier than in the liver (P < 0.05), with maximal decreases at 24 hours of 56% and 85% in the liver and kidney, respectively. In contrast, both hepatic and renal coumarin 7-hydroxylase (COH) activity (indicative of CYP2A5 activity) relative to total CYP content started to progressively increase at 8 hours, with renal activity 61 times higher than the hepatic activity. Maximum increases were observed, 15-fold in the liver and 64-fold in the kidney after 24 hours. Liver and kidney CYP2A5 mRNA levels increased maximally 12 and 4 hours after treatment, respectively and decreased to almost half 6 hours later. In contrast, kidney and liver CYP2A5 protein levels increased maximally at 18 and 24 hours. This study demonstrates that hepatic and renal CYP2A5 is upregulated by cadmium with a faster response in the kidney than in the liver. This observation is concordant with the fact that kidney is the target organ for cadmium toxicity. The observed increase in the mRNA but not in protein levels after maximal induction suggests involvement of post-transcriptional mechanisms in the regulation of CYP2A5 expression by cadmium.
Resumo:
Adult and preadult Dissonus manteri attached to the gills of Plectropomus leopardus cause significant pathology in the form of large hyperplastic nodules on the afferent (leading), edges of gill filaments. Nodules result from the dual actions of parasite attachment and feeding. The host response is characterized by severe epithelial hyperplasia, supplemented by fibroplasia and inflammation. Parasites attach close to the gill arch near the base of filaments. They have little effect on gill vasculature as the maxillipeds penetrate the filament superficial to the efferent filament artery and do not interfere with the blood vessels of the secondary lamellae. Tissue proliferation is limited to the wide portion of filament 'edge' epithelium in the proximal third and also does not extend to the secondary lamellae. Nodules are most numerous towards the ends of hemibranchs and are generally absent from the central regions. Leading hemibranchs bear significantly more nodules than their trailing counterparts. Of the total number of nodules, 20.5% are located on the pseudobranchs. Distribution patterns are considered to be primarily the result of D. manteri avoiding strong water currents, although this cannot explain the difference between numbers on leading and trailing hemibranchs.
Resumo:
In this study, the suitability of two repetitive-element-based PCR (rep-PCR) assays, enterobacterial repetitive intergenic consensus (ERIC)-PCR and BOX-PCR, to rapidly characterize Pseudomonas aeruginosa strains isolated from patients with cystic fibrosis (CF) was examined. ERIC-PCR utilizes paired sequence-specific primers and BOX-PCR a single primer that target highly conserved repetitive elements in the P. aeruginosa genome. Using these rep-PCR assays, 163 P. aeruginosa isolates cultured from sputa collected from 50 patients attending an adult CF clinic and 50 children attending a paediatric CF clinic were typed. The results of the rep-PCR assays were compared to the results of PFGE. All three assays revealed the presence of six major clonal groups shared by multiple patients attending either of the CF clinics, with the dominant clonal group infecting 38% of all patients. This dominant clonal group was not related to the dominant clonal group detected in Sydney or Melbourne (pulsotype 1), nor was it related to the dominant groups detected in the UK. In all, PFGE and rep-PCR identified 58 distinct clonal groups, with only three of these shared between the two clinics. The results of this study showed that both ERIC-PCR and BOX-PCR are rapid, highly discriminatory and reproducible assays that proved to be powerful surveillance screening tools for the typing of clinical P. aeruginosa isolates recovered from patients with CF.
Resumo:
Serotonin (5-hydroxytryptamine, 5-HT) is an amine neurotransmitter derived from tryptophan and is important in brain systems regulating mood, emotional behavior, and sleep. Selective serotonin reuptake inhibitor (SSRI) drugs are used to treat disorders such as depression, stress, eating disorders, autism, and schizophrenia. It is thought that these drugs act to prolong the action of 5-HT by blocking reuptake. This may lead to decreased 5-HT content in the nerve fibers themselves; however, this has not previously been directly demonstrated. We have studied the effects of administration of two drugs, imipramine and citalopram, on levels of 5-HT in nerve fibers in the murine brain. Quantitative analysis of the areal density of 5-HT fibers throughout the brain was performed using ImageJ software. While a high density of fibers was observed in mid- and hind-brain regions and areas such as thalamus and hypothalamus, densities were far lower in areas such as cortex, where SSRIs might be thought to exert their actions. As anticipated, imipramine and citalopram produced a decline in 5-HT levels in nerve fibers, but the result was not uniform. Areas such as inferior colliculus showed significant reduction whereas little, if any, change was observed in the adjacent superior colliculus. The reason for, and significance of, this regionality is unclear. It has been proposed that serotonin effects in the brain might be linked to changes in glutamatergic transmission. Extracellular glutamate levels are regulated primarily by glial glutamate transporters. Qualitative evaluation of glutamate transporter immunolabeling in cortex of control and drug-treated mice revealed no discernable difference in intensity of glutamate transporter immunoreactivity. These data suggest that changes in intracellular and extracellular levels of serotonin do not cause concomitant changes in astroglial glutamate transporter expression, and thus cannot represent a mechanism for the delayed efficacy of antidepressants when administered clinically. © 2005 Elsevier B.V. All rights reserved.
Resumo:
This paper draws on data from a group case study of women in higher education management in Hong Kong, Singapore, Malaysia, and Thailand. I investigate culture-specific dimensions of what the Western literature has conceptualized as glass ceiling impediments to women's career advancement in higher education. I frame my argument within recent debates about globalization and glocalization to show how the push-pull and disjunctive dynamics of globalization are experienced in local sites by social actors who traverse global flows and yet remain tethered to local discourses, values, and practices. All of the women in this study were trained in Western universities and are fluent English speakers, world-class experts in their fields, well versed with equity discourses, and globally connected on international nongovernment organization (NGO) and academic circuits. They are indeed global cosmopolitans. And yet their testimonies indicate that so-called Asian values and religious-cultural ideologies demand the enactment of a specific construct of Asian femininity that militates against meritocratic equality and academic career aspirations to senior management levels. Despite the global nature of the University and increasing global flows of academics, students, and knowledge, the politics of academic glass ceilings are not universal but always locally inflected with cultural values and norms. As such, the politics of disadvantage for women in higher education require local and situated analyses in the context of global patterns of the educational status Of women and the changing nature of higher education.
Resumo:
The focus of this paper is the social construction of physical education teacher education (PETE) and its fate within the broader process of curriculum change in the physical activity field. Our task is to map the dimensions of a research program centered on the social construction of the physical activity field and PETE in higher education. Debates in the pages of Quest and elsewhere over the past two decades have highlighted not only the contentious nature of PETE practices and structures but also that PETE is changing. This paper offers one way of making sense of the ongoing process of contestation and struggle through the presentation of a theoretical framework. This framework, primarily drawing upon the work of Lave and Wenger (1991) and Bernstein (1990, 1996), is described before it is used to study the social construction of PETE in Australia. We assess the progress that has been made in developing this research program, and the questions already evident for further developments of a program of study of the physical activity field in higher education.
Resumo:
The middle years of schooling are receiving increased attention. This paper gives some background to 'middle schooling' and begin discussion if physical education is to be involved in the shift that an increasing number of schools are attempting to make in order to enhance student learning. It addresses findings, innovations and changes to the field of physical education. A set of questions are posed about the relationship between the middle years of schooling, health and physical education.
Resumo:
Much of the research on teachers' work is informed by role theory, that assumes teachers' identity is largely ascribed. When there are inconsistencies in teachers' and others' expectations for different occupational roles such as physical education teacher and sports coach, 'role conflict' is said to occur. This stud), sought to investigate if role conflict was a major concern for Australian physical education teacher/coaches. Findings, informed by case studies with five teacher/coaches, challenge the assumption that moving between professional responsibilities causes role conflict. Rather, in moving across contexts, the physical education teachers managed inconsistencies in ways that resulted in positive and rawarding work experiences.