203 research outputs found
A short form of the Recovery Assessment Scale-Domains and Stages: Development and validation among adults with anxiety disorders
The use of Goal Attainment Scaling in a community health promotion initiative with seniors
<p>Abstract</p> <p>Background</p> <p>Evaluating collaborative community health promotion initiatives presents unique challenges, including engaging community members and other stakeholders in the evaluation process, and measuring the attainment of goals at the collective community level. Goal Attainment Scaling (GAS) is a versatile, under-utilized evaluation tool adaptable to a wide range of situations. GAS actively involves all partners in the evaluation process and has many benefits when used in community health settings.</p> <p>Methods</p> <p>The purpose of this paper is to describe the use of GAS as a potential means of measuring progress and outcomes in community health promotion and community development projects. GAS methodology was used in a local community of seniors (n = 2500; mean age = 76 ± 8.06 SD; 77% female, 23% male) to a) collaboratively set health promotion and community partnership goals and b) objectively measure the degree of achievement, over- or under-achievement of the established health promotion goals. Goal attainment was measured in a variety of areas including operationalizing a health promotion centre in a local mall, developing a sustainable mechanism for recruiting and training volunteers to operate the health promotion centre, and developing and implementing community health education programs. Goal attainment was evaluated at 3 monthly intervals for one year, then re-evaluated again at year 2.</p> <p>Results</p> <p>GAS was found to be a feasible and responsive method of measuring community health promotion and community development progress. All project goals were achieved at one year or sooner. The overall GAS score for the total health promotion project increased from 16.02 at baseline (sum of scale scores = -30, average scale score = -2) to 54.53 at one year (sum of scale scores = +4, average scale score = +0.27) showing project goals were achieved above the expected level. With GAS methodology an amalgamated score of 50 represents the achievement of goals at the expected level.</p> <p>Conclusion</p> <p>GAS provides a "participatory", flexible evaluation approach that involves community members, research partners and other stakeholders in the evaluation process. GAS was found to be "user-friendly" and readily understandable by seniors and other community partners not familiar with program evaluation.</p
Lennox gastaut syndrome, review of the literature and a case report
<p>Abstract</p> <p>Background</p> <p>Lennox-Gastaut syndrome (LGS) is a severe form of childhood epilepsy that is defined by generalized multiple type seizures, slowness of intellectual growth, and a specific EEG disturbance. Children affected might previously have infantile spasms or underlying brain disorder but etiology can be idiopathic. In South Africa, the incidence of secondary epilepsy is higher than what is found in developed countries resulting in higher incidence of the disease. LGS seizures are often treatment resistant and the long term prognosis is poor.</p> <p>Report</p> <p>A twenty six year old female, presented with anterior open bite, macroglossia, supragingival as well as subgingival calculus. The gingiva was red, swollen and friable and there was generalized bleeding and localized suppuration. The patient had gingival recession. After periodontal therapy a remarkable improvement in oral health status was noted.</p> <p>Conclusion</p> <p>The clinical findings in LGS included facial deformities, periodontitis and gingival swellings. Interdisciplinary treatment of these patients is fundamental and oral attention is of outstanding importance. Non-surgical periodontal therapy was effective in controlling periodontal disease in the reported case, but prevention of periodontal and dental diseases is preferable for this high-risk group of patients.</p
Hyperthyroidism and human chorionic gonadotrophin production in gestational trophoblastic disease
Background: Gestational trophoblastic disease (GTD) is a rare complication of pregnancy, ranging from molar pregnancy to choriocarcinoma. Patients with persistent disease require treatment with chemotherapy. For the vast majority, prognosis is excellent. Occasionally, GTD is complicated by hyperthyroidism, which may require treatment. This is thought to occur due to molecular mimicry between human chorionic gonadotrophin (HCG) and thyroid-stimulating hormone (TSH), and hence cross-reactivity with the TSH receptor. Hyperthyroidism usually resolves as the GTD is successfully treated and correspondingly HCG levels normalise.
Methods: This paper reviews cases of GTD treated over a 5-year period at one of the three UK centres and identifies the prevalence of hyperthyroidism in this population. Four cases with clinical hyperthyroidism are discussed.
Results: On review of the 196 patients with gestational trophoblastic neoplasia treated with chemotherapy in Sheffield since 2005, 14 (7%) had biochemical hyperthyroidism. Of these, four had evidence of clinical hyperthyroidism.
Conclusion: Concomitant biochemical thyroid disease in patients with GTD is relatively common, and measurement of thyroid function in patients with persistent GTD is, therefore, important. The development of hyperthyroidism is largely influenced by the level of HCG and disease burden, and usually settles with treatment of the persistent GTD. However, rarely the thyroid stimulation can have potentially life-threatening consequences
Modelling the impact of vector control interventions on Anopheles gambiae population dynamics
<p>Abstract</p> <p>Background</p> <p>Intensive anti-malaria campaigns targeting the <it>Anopheles </it>population have demonstrated substantial reductions in adult mosquito density. Understanding the population dynamics of <it>Anopheles </it>mosquitoes throughout their whole lifecycle is important to assess the likely impact of vector control interventions alone and in combination as well as to aid the design of novel interventions.</p> <p>Methods</p> <p>An ecological model of <it>Anopheles gambiae sensu lato </it>populations incorporating a rainfall-dependent carrying capacity and density-dependent regulation of mosquito larvae in breeding sites is developed. The model is fitted to adult mosquito catch and rainfall data from 8 villages in the Garki District of Nigeria (the 'Garki Project') using Bayesian Markov Chain Monte Carlo methods and prior estimates of parameters derived from the literature. The model is used to compare the impact of vector control interventions directed against adult mosquito stages - long-lasting insecticide treated nets (LLIN), indoor residual spraying (IRS) - and directed against aquatic mosquito stages, alone and in combination on adult mosquito density.</p> <p>Results</p> <p>A model in which density-dependent regulation occurs in the larval stages via a linear association between larval density and larval death rates provided a good fit to seasonal adult mosquito catches. The effective mosquito reproduction number in the presence of density-dependent regulation is dependent on seasonal rainfall patterns and peaks at the start of the rainy season. In addition to killing adult mosquitoes during the extrinsic incubation period, LLINs and IRS also result in less eggs being oviposited in breeding sites leading to further reductions in adult mosquito density. Combining interventions such as the application of larvicidal or pupacidal agents that target the aquatic stages of the mosquito lifecycle with LLINs or IRS can lead to substantial reductions in adult mosquito density.</p> <p>Conclusions</p> <p>Density-dependent regulation of anopheline larvae in breeding sites ensures robust, stable mosquito populations that can persist in the face of intensive vector control interventions. Selecting combinations of interventions that target different stages in the vector's lifecycle will result in maximum reductions in mosquito density.</p
Exact score distribution computation for ontological similarity searches
<p>Abstract</p> <p>Background</p> <p>Semantic similarity searches in ontologies are an important component of many bioinformatic algorithms, e.g., finding functionally related proteins with the Gene Ontology or phenotypically similar diseases with the Human Phenotype Ontology (HPO). We have recently shown that the performance of semantic similarity searches can be improved by ranking results according to the probability of obtaining a given score at random rather than by the scores themselves. However, to date, there are no algorithms for computing the exact distribution of semantic similarity scores, which is necessary for computing the exact <it>P</it>-value of a given score.</p> <p>Results</p> <p>In this paper we consider the exact computation of score distributions for similarity searches in ontologies, and introduce a simple null hypothesis which can be used to compute a <it>P</it>-value for the statistical significance of similarity scores. We concentrate on measures based on Resnik's definition of ontological similarity. A new algorithm is proposed that collapses subgraphs of the ontology graph and thereby allows fast score distribution computation. The new algorithm is several orders of magnitude faster than the naive approach, as we demonstrate by computing score distributions for similarity searches in the HPO. It is shown that exact <it>P</it>-value calculation improves clinical diagnosis using the HPO compared to approaches based on sampling.</p> <p>Conclusions</p> <p>The new algorithm enables for the first time exact <it>P</it>-value calculation via exact score distribution computation for ontology similarity searches. The approach is applicable to any ontology for which the annotation-propagation rule holds and can improve any bioinformatic method that makes only use of the raw similarity scores. The algorithm was implemented in Java, supports any ontology in OBO format, and is available for non-commercial and academic usage under: <url>https://compbio.charite.de/svn/hpo/trunk/src/tools/significance/</url></p
Seasonal variation of non-shivering thermogenesis (NST) during mild cold exposure
Background: The physiological function of non-shivering thermogenesis (NST) has been investigated in recent years, and some studies have discussed the importance of NST with respect to human cold adaptation. The present study aimed to clarify individual and seasonal variations in NST that occurred as a result of mild cold exposure.Methods: Seventeen male university students participated in the present study during summer and winter. The climate chamber used was programmed so that ambient temperature dropped from 28°C to 16°C over an 80-min period. Physiological parameters of test subjects were recorded during the experiments.Results: Increases in oxygen intake (VO2) during cold exposure were significantly greater without shivering in winter than they were in summer. Respiratory exchange ratio (RER) was significantly lower during thermoneutral baseline and cold exposure in winter than it was during the same periods in summer. In addition, there was a significant negative correlation between ΔVO2 and ΔRER.Conclusions: Increase of VO2 without shivering indicated increase of NST, and decrease of RER depends on the metabolization of fat in winter. These results suggested that NST activity was activated by seasonal acclimatization, and individual variation of NST depends on individual variation of fat metabolism
Application of the lumped age-class technique to studying the dynamics of malaria-mosquito-human interactions
A series of models of malaria-mosquito-human interactions using the Lumped Age-Class technique of Gurney & Nisbet are developed. The models explicitly include sub-adult mosquito dynamics and assume that population regulation occurs at the larval stage. A challenge for modelling mosquito dynamics in continuous time is that the insect has discrete life-history stages (egg, larva, pupa & adult), the sub-adult stages of relatively fixed duration, which are subject to very different demographic rates. The Lumped Age-Class technique provides a natural way to treat this type of population structure. The resulting model, phrased as a system of delay-differential equations, is only slightly harder to analyse than traditional ordinary differential equations and much easier than the alternative partial differential equation approach. The Lumped Age-Class technique also allows the natural treatment of the relatively fixed time delay between the mosquito ingesting Plasmodium and it becoming infective. Three models are developed to illustrate the application of this approach: one including just the mosquito dynamics, the second including Plasmodium but no human dynamics, and the third including the interaction of the malaria pathogen and the human population (though only in a simple classical Ross-Macdonald manner). A range of epidemiological quantities used in studying malaria such as the vectorial capacity, the entomological inoculation rate and the basic reproductive number (R0) are derived, and examples given of the analysis and simulation of model dynamics. Assumptions and extensions are discussed. It is suggested that this modelling framework may be a natural and useful tool for exploring a variety of issues in malaria-vector epidemiology, especially in circumstances where a dynamic representation of mosquito recruitment is required
SNi from SN2: a front-face mechanism ‘synthase’ engineered from a retaining hydrolase
SNi or SNi-like mechanisms, in which leaving group departure and nucleophile approach occur on the same ‘front’ face, have been observed previously experimentally and computationally in both the chemical and enzymatic (glycosyltransferase) substitution reactions of α-glycosyl electrophiles. Given the availability of often energetically comparable competing pathways for substitution (SNi vs SN1 vs SN2) the precise modulation of this archetypal reaction type should be feasible. Here, we show that the drastic engineering of a protein that catalyzes substitution, a retaining β-glycosidase (from Sulfolobus solfataricus SSβG), apparently changes the mode of reaction from “SN2” to “SNi”. Destruction of the nucleophilic Glu387 of SSβG-WT through Glu387Tyr mutation (E387Y) created a catalyst (SSβG-E387Y) with lowered but clear transglycosylation substitution activity with activated substrates, altered substrate and reaction preferences and hence useful synthetic (‘synthase’) utility by virtue of its low hydrolytic activity with unactivated substrates. Strikingly, the catalyst still displayed retaining β stereoselectivity, despite lacking a suitable nucleophile; pH-activity profile, mechanism-based inactivators and mutational analyses suggest that SSβG-E387Y operates without either the use of nucleophile or general acid/base residues, consistent with a SNi or SNi-like mechanism. An x-ray structure of SSβG-E387Y and subsequent metadynamics simulation suggest recruitment of substrates aided by a π-sugar interaction with the introduced Tyr387 and reveal a QM/MM free energy landscape for the substitution reaction catalyzed by this unnatural enzyme similar to those of known natural, SNi-like glycosyltransferase (GT) enzymes. Proton flight from the putative hydroxyl nucleophile to the developing p-nitrophenoxide leaving group of the substituted molecule in the reactant complex creates a hydrogen bond that appears to crucially facilitate the mechanism, mimicking the natural mechanism of SNi-GTs. An oxocarbenium ion-pair minimum along the reaction pathway suggests a step-wise SNi-like DN*ANss rather than a concerted SNi DNAN mechanism. This first observation of a front face mechanism in a β-retaining glycosyl transfer enzyme highlights, not only that unusual SNi reaction pathways may be accessed through direct engineering of catalysts with suitable environments, but also suggests that ‘β-SNi’ reactions are also feasible for glycosyl transfer enzymes and the more widespread existence of SNi or SNi-like mechanism in nature
Molecular Phylogenetic Evaluation of Classification and Scenarios of Character Evolution in Calcareous Sponges (Porifera, Class Calcarea)
Calcareous sponges (Phylum Porifera, Class Calcarea) are known to be taxonomically difficult. Previous molecular studies have revealed many discrepancies between classically recognized taxa and the observed relationships at the order, family and genus levels; these inconsistencies question underlying hypotheses regarding the evolution of certain morphological characters. Therefore, we extended the available taxa and character set by sequencing the complete small subunit (SSU) rDNA and the almost complete large subunit (LSU) rDNA of additional key species and complemented this dataset by substantially increasing the length of available LSU sequences. Phylogenetic analyses provided new hypotheses about the relationships of Calcarea and about the evolution of certain morphological characters. We tested our phylogeny against competing phylogenetic hypotheses presented by previous classification systems. Our data reject the current order-level classification by again finding non-monophyletic Leucosolenida, Clathrinida and Murrayonida. In the subclass Calcinea, we recovered a clade that includes all species with a cortex, which is largely consistent with the previously proposed order Leucettida. Other orders that had been rejected in the current system were not found, but could not be rejected in our tests either. We found several additional families and genera polyphyletic: the families Leucascidae and Leucaltidae and the genus Leucetta in Calcinea, and in Calcaronea the family Amphoriscidae and the genus Ute. Our phylogeny also provided support for the vaguely suspected close relationship of several members of Grantiidae with giantortical diactines to members of Heteropiidae. Similarly, our analyses revealed several unexpected affinities, such as a sister group relationship between Leucettusa (Leucaltidae) and Leucettidae and between Leucascandra (Jenkinidae) and Sycon carteri (Sycettidae). According to our results, the taxonomy of Calcarea is in desperate need of a thorough revision, which cannot be achieved by considering morphology alone or relying on a taxon sampling based on the current classification below the subclass level
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