1,233 research outputs found
Phylogenetic And Molecular Variability Studies Reveal A New Genetic Clade Of Citrus Leprosis Virus C
Conselho Nacional de Desenvolvimento CientĆfico e TecnolĆ³gico (CNPq)Citrus leprosis virus C (CiLV-C) causes a severe disease affecting citrus orchards in the Western hemisphere. This study reveals the molecular variability of the virus by analyzing four genomic regions (p29, p15, MP and RNA2-intergenic region) distributed over its two RNAs. Nucleotide diversity (pi) values were relatively low but statistically different over the analyzed genes and subpopulations, indicating their distinct evolutionary history. Values of pi(p29) and pi(MP) were higher than those of pi(p15) and pi(RNA2-IR), whereas pi(MP) was increased due to novel discovered isolates phylogenetically clustered in a divergent clade that we called SJP. Isolate BR_SP_SJP_01 RNA1 and RNA2 sequences, clade SJP, showed an identity of 85.6% and 88.4%, respectively, with those corresponding to CiLV-C, the type member of the genus Cilevirus, and its RNA2 5'-proximal region was revealed as a minor donor in a putative inter-clade recombination event. In addition to citrus, BR_SP_SJP_01 naturally infects the weed Commelina benghalensis and is efficiently transmitted by Brevipalpus yothersi mites. Our data demonstrated that negative selection was the major force operating in the evaluated viral coding regions and defined amino acids putatively relevant for the biological function of cilevirus proteins. This work provides molecular tools and sets up a framework for further epidemiological studies.8Conselho Nacional de Desenvolvimento Cientifico e Tecnologico [375843/2012-4, 481771/2013-1, 401564/2012-6]Fundacao de Apoio a Pesquisa no Estado de Sao Paulo [2012/18771-0, 2012/20667-7, 2014/08458-9]Conselho Nacional de Desenvolvimento CientĆfico e TecnolĆ³gico (CNPq
Incidence of myopia in Swedish schoolchildren: A longitudinal study
Purpose: The prevalence of myopia in Scandinavia tends to be lower than in other parts of the world. This study aimed to investigate the incidence of myopia and its predictors in Swedish children to characterise this trend. Methods: A 2-year longitudinal study was conducted following a cohort of schoolchildren aged 8ā16 years. Myopia was defined as a spherical equivalent refraction (SER) ā¤ ā0.50 D. The study enrolled 128 participants, 70 (55%) females with a mean age of 12.0 years (SD = 2.4). Results: The cumulative incidence of myopia during the follow-up period was 5.5%, and the incidence rate of myopia was 3.2 cases per 100 person-years. Participants with myopia at baseline exhibited a faster increase in refractive error during the follow-up period. Likewise, participants with two myopic parents exhibited a more marked change towards myopia, regardless of their initial refractive error. Conclusion: In the current study, similar to prevalence, the incidence of myopia was low when compared with other parts of the world. These results lead us to formulate a new hypothesis that the normal emmetropisation process may be protected by low educational pressure practised in Sweden during early childhood. Further research is necessary to test this new hypothesis. Ā© 2024 The Author(s). Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.This study was supported by Specsavers Sweden AB, the faculty of Health and Life Sciences, Linnaeus University and the Brien Holden Vision Institute
Intellectual disability, unusual facial morphology and hand anomalies in sibs
Here we report on a Portuguese family with three sisters who shared moderate intellectual disability, unusual facial morphology (short palpebral fissures; broad nasal tip; thin upper and lower vermillion; broad and pointed chin) and hand anomalies in two of them (short left third and fifth right metacarpals in one case; marked syndactyly between the third and fourth fingers in another). One of the sisters had microcephaly and short stature, and the other two were obese. Obesity and somewhat similar facial features were also present in the otherwise healthy mother. Despite the overlap with several known syndromes (Albright osteodystrophy; Filippi syndrome; Rubinstein-Taybi syndrome; microdeletion 2q37), we suggest this condition is previously unreported, and most likely displays an autosomal recessive pattern of inheritance
Intellectual disability, coarse face, relative macrocephaly, and cerebellar hypotrophy in two sisters
We report on two Portuguese sisters with a very similar phenotype characterized by severe intellectual disability, absent speech, relative macrocephaly, coarse face, cerebellar hypotrophy, and severe ataxia. Additional common features include increased thickness of the cranial vault, delayed dental eruption, talipes equino-varus, clinodactyly, and camptodactyly of the fifth finger. The older sister has retinal dystrophy and the younger sister has short stature. Their parents are consanguineous. We suggest this condition constitutes a previously unreported autosomal recessive entity
Diabetic Macular Edema Characterization and Visualization Using Optical Coherence Tomography Images
Diabetic Retinopathy and Diabetic Macular Edema (DME) represent one of the main causes of blindness in developed countries. They are characterized by fluid deposits in the retinal layers, causing a progressive vision loss over the time. The clinical literature defines three DME types according to the texture and disposition of the fluid accumulations: Cystoid Macular Edema (CME), Diffuse Retinal Thickening (DRT) and Serous Retinal Detachment (SRD). Detecting each one is essential as, depending on their presence, the expert will decide on the adequate treatment of the pathology. In this work, we propose a robust detection and visualization methodology based on the analysis of independent image regions. We study a complete and heterogeneous library of 375 texture and intensity features in a dataset of 356 labeled images from two of the most used capture devices in the clinical domain: a CIRRUSTM HD-OCT 500 Carl Zeiss Meditec and 179 OCT images from a modular HRA + OCT SPECTRALIS(R) from Heidelberg Engineering, Inc. We extracted 33,810 samples for each type of DME for the feature analysis and incremental training of four different classifier paradigms. This way, we achieved an 84.04% average accuracy for CME, 78.44% average accuracy for DRT and 95.40% average accuracy for SRD. These models are used to generate an intuitive visualization of the fluid regions. We use an image sampling and voting strategy, resulting in a system capable of detecting and characterizing the three types of DME presenting them in an intuitive and repeatable way
Effectiveness, cost-effectiveness and cost-benefit of a single annual professional intervention for the prevention of childhood dental caries in a remote rural Indigenous community
Background
The aim of the study is to reduce the high prevalence of tooth decay in children in a remote, rural Indigenous community in Australia, by application of a single annual dental preventive intervention. The study seeks to (1) assess the effectiveness of an annual oral health preventive intervention in slowing the incidence of dental caries in children in this community, (2) identify the mediating role of known risk factors for dental caries and (3) assess the cost-effectiveness and cost-benefit of the intervention.
Methods/design
The intervention is novel in that most dental preventive interventions require regular re-application, which is not possible in resource constrained communities. While tooth decay is preventable, self-care and healthy habits are lacking in these communities, placing more emphasis on health services to deliver an effective dental preventive intervention. Importantly, the study will assess cost-benefit and cost-effectiveness for broader implementation across similar communities in Australia and internationally.
Discussion
There is an urgent need to reduce the burden of dental decay in these communities, by implementing effective, cost-effective, feasible and sustainable dental prevention programs. Expected outcomes of this study include improved oral and general health of children within the community; an understanding of the costs associated with the intervention provided, and its comparison with the costs of allowing new lesions to develop, with associated treatment costs. Findings should be generalisable to similar communities around the world.
The research is registered with the Australian New Zealand Clinical Trials Registry (ANZCTR), registration number ACTRN12615000693527; date of registration: 3rd July 2015
Who fans the flames of Alzheimer's disease brains? Misfolded tau on the crossroad of neurodegenerative and inflammatory pathways
Neurodegeneration, induced by misfolded tau protein, and neuroinflammation, driven by glial cells, represent the salient features of Alzheimer's disease (AD) and related human tauopathies. While tau neurodegeneration significantly correlates with disease progression, brain inflammation seems to be an important factor in regulating the resistance or susceptibility to AD neurodegeneration. Previously, it has been shown that there is a reciprocal relationship between the local inflammatory response and neurofibrillary lesions. Numerous independent studies have reported that inflammatory responses may contribute to the development of tau pathology and thus accelerate the course of disease. It has been shown that various cytokines can significantly affect the functional and structural properties of intracellular tau. Notwithstanding, anti-inflammatory approaches have not unequivocally demonstrated that inhibition of the brain immune response can lead to reduction of neurofibrillary lesions. On the other hand, our recent data show that misfolded tau could represent a trigger for microglial activation, suggesting the dual role of misfolded tau in the Alzheimer's disease inflammatory cascade. On the basis of current knowledge, we can conclude that misfolded tau is located at the crossroad of the neurodegenerative and neuroinflammatory pathways. Thus disease-modified tau represents an important target for potential therapeutic strategies for patients with Alzheimer's disease
Sex-specific differences in the synaptonemal complex in the genus Oreochromis (Cichlidae)
Total synaptonemal complex (SC) lengths were estimated from Oreochromis aureus Steindachner (which has a WZ/ZZ sex determination system), O. mossambicus Peters and O. niloticus L. (both of which have XX/XY sex determination systems). The total SC length in oocytes was greater than that in spermatocytes in all three species (194Ā±30 Ī¼m and 134Ā±13 Ī¼m, 187Ā±22 Ī¼m and 127Ā±17 Ī¼m, 193Ā±37 Ī¼m and 144Ā±19 Ī¼m, respectively). These sex-specific differences did not appear to be influenced by the type of sex determination system (the female/male total SC length ratio was 1.45 in O. aureus, 1.47 in O. mossambicus and 1.34 in O. niloticus) and do not correlate with the lack of any overall sex-specific length differences in the current Oreochromis linkage map. Although based on data from relatively few species, there appears to be no consistent relationship between sex-specific SC lengths and linkage map lengths in fish. Neomale (hormonally masculinized genetic female) O. aureus and O. mossambicus had total SC lengths of 138Ā±13 Ī¼m and 146Ā±13 Ī¼m respectively, more similar to normal males than to normal females. These findings agree with data from other vertebrate species that suggest that phenotypic sex, rather than genotype, determines traits such as total SC length, chiasmata position and recombination pattern, at least for the autosomes
The use of informal care by people with vision impairment
PURPOSE: To estimate and characterize the use of informal care by people with vision impairment in Portugal. METHODS: A total of 546 visually impaired individuals were recruited from Portuguese hospitals. Clinical information was obtained from medical records, socio-demographic details and informal care use were collected during face-to-face interviews. In addition, participants responded to a functional vision questionnaire (activity inventory) to assess their visual ability. Logistic regression was used to determine independent factors associated with informal care use and linear regression was used to determine independent predictors of intensity of informal care use. RESULTS: Informal care was reported by 39.6% of the participants. The probability of reporting informal care was higher in non-married, those with comorbidities, with lower visual ability and worse visual acuity. The median number of caregivers' hours per year was 390 (mean = 470; 95%CI = 488-407), which represent a median opportunity cost of ā¬2,586. Visual ability was the only independent predictor of number of hours of informal care received. CONCLUSIONS: Informal care was frequently used by individuals with impaired vision. Improving visual ability of people with impaired vision when performing valued activities may reduce the burden of visual loss at personal and societal level. This could be achieved with person-centred visual rehabilitation
The association between family and community social capital and health risk behaviours in young people: an integrative review
Background:
Health risk behaviours known to result in poorer outcomes in adulthood are generally established in late childhood and adolescence. These āriskyā behaviours include smoking, alcohol and illicit drug use and sexual risk taking. While the role of social capital in the establishment of health risk behaviours in young people has been explored, to date, no attempt has been made to consolidate the evidence in the form of a review. Thus, this integrative review was undertaken to identify and synthesise research findings on the role and impact of family and community social capital on health risk behaviours in young people and provide a consolidated evidence base to inform multi-sectorial policy and practice.<p></p>
Methods:
Key electronic databases were searched (i.e. ASSIA, CINAHL, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, Embase, Medline, PsycINFO, Sociological Abstracts) for relevant studies and this was complemented by hand searching. Inclusion/exclusion criteria were applied and data was extracted from the included studies. Heterogeneity in study design and the outcomes assessed precluded meta-analysis/meta-synthesis; the results are therefore presented in narrative form.<p></p>
Results:
Thirty-four papers satisfied the review inclusion criteria; most were cross-sectional surveys. The majority of the studies were conducted in North America (n=25), with three being conducted in the UK. Sample sizes ranged from 61 to 98,340. The synthesised evidence demonstrates that social capital is an important construct for understanding the establishment of health risk behaviours in young people. The different elements of family and community social capital varied in terms of their saliency within each behavioural domain, with positive parentāchild relations, parental monitoring, religiosity and school quality being particularly important in reducing risk.<p></p>
Conclusions:
This review is the first to systematically synthesise research findings about the association between social capital and health risk behaviours in young people. While providing evidence that may inform the development of interventions framed around social capital, the review also highlights key areas where further research is required to provide a fuller account of the nature and role of social capital in influencing the uptake of health risk behaviours.<p></p>
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