535 research outputs found
Dimensões ecológicas do controle e gerenciamento de doenças transmitidas por vetores
The paper explores the ecological dimension of vector-borne diseases in order to clarify the role of "ecological thinking" in the development and implementation of vector control activities. It traces some anthropogenic factors in research, and reviews a systems ecology of dengue and Chagas disease. Vector-borne diseases are essentially ecological problems that span biophysical, social, and economic environments. The paper views the ecological dimension as a unifying element that can provide direction in research, with a holistic perspective important for all participants/stakeholders involved
Cost-effectiveness of continuous glucose monitoring and intensive insulin therapy for type 1 diabetes
<p>Abstract</p> <p>Background</p> <p>Our objective was to determine the cost-effectiveness of Continuous Glucose Monitoring (CGM) technology with intensive insulin therapy compared to self-monitoring of blood glucose (SMBG) in adults with type 1 diabetes in the United States.</p> <p>Methods</p> <p>A Markov cohort analysis was used to model the long-term disease progression of 12 different diabetes disease states, using a cycle length of 1 year with a 33-year time horizon. The analysis uses a societal perspective to model a population with a 20-year history of diabetes with mean age of 40. Costs are expressed in 23,552, resulting in an ICER of approximately 100,000/QALY, CGM with intensive insulin therapy was cost-effective in 70% of the Monte Carlo simulations.</p> <p>Conclusions</p> <p>CGM with intensive insulin therapy appears to be cost-effective relative to SMBG and other societal health interventions.</p
Seroprevalence of simian immunodeficiency virus in wild and captive born Sykes' monkeys (Cercopithecus mitis) in Kenya
BACKGROUND: The Sykes' monkey and related forms (Cercopithecus mitis) make up an abundant, widespread and morphologically diverse species complex in eastern Africa that naturally harbors a distinct simian immunodeficiency virus (SIVsyk). We carried out a retrospective serological survey of SIV infection from both wild and captive Sykes' monkeys from Kenya. We compared two commercially available, cross-reactive ELISA tests using HIV antigens with a novel SIVsyk antigen-specific Western blot assay and analyzed the data by origin, subspecies, age and sex. RESULTS: The SIVsyk antigen-specific Western blot assay detected more serum samples as positive than either of the cross-reactive ELISA assays. Using this assay, we found that seroprevalence is higher than previously reported, but extremely variable in wild populations (from 0.0 to 90.9%). Females were infected more often than males in both wild and captive populations. Seropositive infants were common. However, no seropositive juveniles were identified. CONCLUSION: We have developed a specific and sensitive Western blot assay for anti-SIVsyk antibody detection. Sykes' monkeys are commonly infected with SIVsyk, but with extremely variable prevalence in the wild. Higher infection prevalence in females suggests predominantly sexual transmission. High infection prevalence in infants, but none in juveniles, suggests maternal antibodies, but little or no vertical transmission
Detailed characterization of a long-term rodent model of critical illness and recovery
Objective: To characterize a long-term model of recovery from critical illness, with particular emphasis on cardiorespiratory, metabolic, and muscle function. Design: Randomized controlled animal study. Setting: University research laboratory. Subjects: Male Wistar rats. Interventions: Intraperitoneal injection of the fungal cell wall constituent, zymosan or n-saline. Measurements and Main Results: Following intervention, rats were followed for up to 2 weeks. Animals with zymosan peritonitis reached a clinical and biochemical nadir on day 2. Initial reductions were seen in body weight, total body protein and fat, and muscle mass. Leg muscle fiber diameter remained subnormal at 14 days with evidence of persisting myonecrosis, even though gene expression of regulators of muscle mass (e.g., MAFbx, MURF1, and myostatin) had peaked on days 2–4 but normalized by day 7. Treadmill exercise capacity, forelimb grip strength, and in vivo maximum tetanic force were also reduced. Food intake was minimal until day 4 but increased thereafter. This did not relate to appetite hormone levels with early (6 hr) rises in plasma insulin and leptin followed by persisting subnormal levels; ghrelin levels did not change. Serum interleukin-6 level peaked at 6 hours but had normalized by day 2, whereas interleukin-10 remained persistently elevated and high-density lipoprotein cholesterol persistently depressed. There was an early myocardial depression and rise in core temperature, yet reduced oxygen consumption and respiratory exchange ratio with a loss of diurnal rhythmicity that showed a gradual but incomplete recovery by day 7. Conclusions: This detailed physiological, metabolic, hormonal, functional, and histological muscle characterization of a model of critical illness and recovery reproduces many of the findings reported in human critical illness. It can be used to assess putative therapies that may attenuate loss, or enhance recovery, of muscle mass and function
Cosmological History of Stars and Metals
We study the evolution of stellar content and the chemical enrichment of the
universe averaged over the whole population of galaxies by means of a series of
chemo-spectrophotometric models that take into account the metallicity and dust
obscuration effects. We investigate various classes of cosmic star formation
rates (CSFR) histories consistent with current estimations. We are able to
reproduce a variety of observational constraints such as the emissivities at
rest-frame 0.44, 25, 60 and 100 m of the local universe and also the
overall shape of the extragalactic background light from UV/NIR galaxy counts
and the cosmic infrared background (CIB) from DIRBE/FIRAS measurements. We find
that the CIB at 140 m is crucial for discriminating between the CSFR
histories. The best-fit model to this constraint seems to favour mid-infrared
derived CSFR at low- and a flat CSFR at higher consistent with the most
recent estimations, although the shape of the CSFR at high redshifts has little
impact on the FIR/submm part of extragalactic background. We suggest that the
bulk of the CIB energy is produced by a population of moderately obscured
normal galaxies lying at . We then derive the global chemical
enrichment and stellar content of the universe and find that this model
predicts metallicities in good agreement with the metallicity in DLAs given
that some outflow of metal-enriched gas from galaxies is assumed, but it
overproduces the current present-day stellar mass density and NIR luminosity
density.Comment: 11 pages, 7 figures, accepted in Astronomy and Astrophysic
Features of the primary wall CESA complex in wild type and cellulose-deficient mutants of Arabidopsis thaliana
Evidence from genetics, co-precipitation and bimolecular fluorescence complementation suggest that three CESAs implicated in making primary wall cellulose in Arabidopsis thaliana form a complex. This study shows the complex has a Mr of approximately 840 kDa in detergent extracts and that it has undergone distinctive changes when extracts are prepared from some cellulose-deficient mutants. The mobility of CESAs 1, 3, and 6 in a Triton-soluble microsomal fraction subject to blue native polyacrylamide gel electrophoresis was consistent with a Mr of about 840 kDa. An antibody specific to any one CESA pulled down all three CESAs consistent with their occupying the same 840 kDa complex. In rsw1, a CESA1 missense mutant, extracts of seedlings grown at the permissive temperature have an apparently normal CESA complex that was missing from extracts of seedlings grown at the restrictive temperature where CESAs precipitated independently. In prc1-19, with no CESA6, CESAs 1 and 3 were part of a 420 kDa complex in extracts of light-grown seedlings that was absent from extracts of dark-grown seedlings where the CESAs precipitated independently. Two CESA3 missense mutants retained apparently normal CESA complexes as did four cellulose-deficient mutants defective in proteins other than CESAs. The 840 kDa complex could contain six CESA subunits and, since loss of plasma membrane rosettes accompanies its loss in rsw1, the complex could form one of the six particles which electron microscopy reveals in rosettes
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Re-evaluation of the mechanisms of dietary fibre and implications for macronutrient bioaccessibility, digestion and postprandial metabolism
The positive effects of dietary fibre on health are now widely recognised; however, our understanding of the mechanisms involved in producing such benefits remains unclear. There are even uncertainties about how dietary fibre in plant foods should be defined and analysed. This review attempts to clarify the confusion regarding the mechanisms of action of dietary fibre and deals with current knowledge on the wide variety of dietary fibre materials, comprising mainly of NSP that are not digested by enzymes of the gastrointestinal (GI) tract. These non-digestible materials range from intact cell walls of plant tissues to individual polysaccharide solutions often used in mechanistic studies. We discuss how the structure and properties of fibre are affected during food processing and how this can impact on nutrient digestibility. Dietary fibre can have multiple effects on GI function, including GI transit time and increased digesta viscosity, thereby affecting flow and mixing behaviour. Moreover, cell wall encapsulation influences macronutrient digestibility through limited access to digestive enzymes and/or substrate and product release. Moreover, encapsulation of starch can limit the extent of gelatinisation during hydrothermal processing of plant foods. Emphasis is placed on the effects of diverse forms of fibre on rates and extents of starch and lipid digestion, and how it is important that a better understanding of such interactions with respect to the physiology and biochemistry of digestion is needed. In conclusion, we point to areas of further investigation that are expected to contribute to realisation of the full potential of dietary fibre on health and well-being of humans
Growing Environmental Activists: Developing Environmental Agency and Engagement Through Children’s Fiction.
We explore how story has the potential to encourage environmental engagement and a sense of agency provided that critical discussion takes place. We illuminate this with reference to the philosophies of John Macmurray on personal agency and social relations; of John Dewey on the primacy of experience for philosophy; and of Paul Ricoeur on hermeneutics, dialogue, dialectics and narrative. We view the use of fiction for environmental understanding as hermeneutic, a form of conceptualising place which interprets experience and perception. The four writers for young people discussed are Ernest Thompson Seton, Kenneth Grahame, Michelle Paver and Philip Pullman. We develop the concept of critical dialogue, and link this to Crick's demand for active democratic citizenship. We illustrate the educational potential for environmental discussions based on literature leading to deeper understanding of place and environment, encouraging the belief in young people that they can be and become agents for change. We develop from Zimbardo the key concept of heroic resister to encourage young people to overcome peer pressure. We conclude with a call to develop a greater awareness of the potential of fiction for learning, and for writers to produce more focused stories engaging with environmental responsibility and activism
The sensory school: working with teachers, parents and pupils to create good sensory conditions
Purpose: An alliance of schools and researchers formed a collaborative community of practice in order to understand and improve the sensory school environment for pupils on the autistic spectrum, and incorporate the findings into school improvement planning. The paper aims to discuss this issue.
Design/methodology/approach: Representatives of special and mainstream schools in South London and a team of researchers formed the project team, including an autistic researcher. The researchers and a named staff member from each of the schools met regularly over the course of 18 months in order to work on an iterative process to improve the sensory experience pupils had of the school environment. Each school completed sensory audits and observations, and was visited by members of the research team. Parents were involved via meetings with the research team and two conferences were organised to share findings.
Findings: Useful outcomes included: developing and sharing of good practice between schools; opportunities for parents of autistic pupils to discuss their concerns, particularly with someone with insider perspective; and exploration of creative ways to achieve pupil involvement and the idea that good autism practice has the potential to benefit all pupils. A resource pack was produced for the schools to access. Plans are in place to revisit the initiative in 12 months’ time in order to ascertain whether there have been long-term benefits.
Originality/value: Projects building communities of practice involving autistic people as core team members are rare, yet feedback from those involved in the project showed this to be a key aspect of shared learning
Determination of freedom-from-rabies for small Indian mongoose populations in the United States Virgin Islands, 2019–2020
Mongooses, a nonnative species, are a known reservoir of rabies virus in the Caribbean region. A cross-sectional study of mongooses at 41 field sites on the US Virgin Islands of St. Croix, St. John, and St. Thomas captured 312 mongooses (32% capture rate). We determined the absence of rabies virus by antigen testing and rabies virus exposure by antibody testing in mongoose populations on all three islands. USVI is the first Caribbean state to determine freedom-from-rabies for its mongoose populations with a scientifically-led robust cross-sectional study. Ongoing surveillance activities will determine if other domestic and wildlife populations in USVI are rabies-free
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