225 research outputs found
Amblyopia and quality of life: a systematic review
Background/Aims
Amblyopia is a common condition which can affect up to 5% of the general population. The health-related quality of life (HRQoL) implications of amblyopia and/or its treatment have been explored in the literature.
Methods
A systematic literature search was undertaken (16th-30th January 2007) to identify the HRQoL implications of amblyopia and/or its treatment.
Results
A total of 25 papers were included in the literature review. The HRQoL implications of amblyopia related specifically to amblyopia treatment, rather than the condition itself. These included the impact upon family life; social interactions; difficulties undertaking daily activities; and feelings and behaviour. The identified studies adopted a number of methodologies. The study populations included; children with the condition; parents of children with amblyopia; and adults who had undertaken amblyopia treatment as a child. Some studies developed their own measures of HRQoL, and others determined HRQoL through proxy measures.
Conclusions
The reported findings of the HRQoL implications are of importance when considering the management of cases of amblyopia. Further research is required to assess the immediate and long-term effects of amblyopia and/or its treatment upon HRQoL using a more standardised approach
Alcohol and HIV Disease Progression: Weighing the Evidence
Heavy alcohol use is commonplace among HIV-infected individuals; however, the extent that alcohol use adversely impacts HIV disease progression has not been fully elucidated. Fairly strong evidence suggests that heavy alcohol consumption results in behavioral and biological processes that likely increase HIV disease progression, and experimental evidence of the biological effect of heavy alcohol on simian immunodeficiency virus in macaques is quite suggestive. However, several observational studies of the effect of heavy alcohol consumption on HIV progression conducted in the 1990s found no association of heavy alcohol consumption with time to AIDS diagnosis, while some more recent studies showed associations of heavy alcohol consumption with declines of CD4 cell counts and nonsuppression of HIV viral load. We discuss several plausible biological and behavioral mechanisms by which alcohol may cause HIV disease progression, evidence from prospective observational human studies, and suggest future research to further illuminate this important issue
Kinome rewiring reveals AURKA limits PI3K-pathway inhibitor efficacy in breast cancer.
Dysregulation of the PI3K-AKT-mTOR signaling network is a prominent feature of breast cancers. However, clinical responses to drugs targeting this pathway have been modest, possibly because of dynamic changes in cellular signaling that drive resistance and limit drug efficacy. Using a quantitative chemoproteomics approach, we mapped kinome dynamics in response to inhibitors of this pathway and identified signaling changes that correlate with drug sensitivity. Maintenance of AURKA after drug treatment was associated with resistance in breast cancer models. Incomplete inhibition of AURKA was a common source of therapy failure, and combinations of PI3K, AKT or mTOR inhibitors with the AURKA inhibitor MLN8237 were highly synergistic and durably suppressed mTOR signaling, resulting in apoptosis and tumor regression in vivo. This signaling map identifies survival factors whose presence limits the efficacy of targeted therapies and reveals new drug combinations that may unlock the full potential of PI3K-AKT-mTOR pathway inhibitors in breast cancer
Vegetation Type Dominates the Spatial Variability in CH<inf>4</inf> Emissions Across Multiple Arctic Tundra Landscapes
Methane (CH4) emissions from Arctic tundra are an important feedback to global climate. Currently, modelling and predicting CH4 fluxes at broader scales are limited by the challenge of upscaling plot-scale measurements in spatially heterogeneous landscapes, and by uncertainties regarding key controls of CH4 emissions. In this study, CH4 and CO2 fluxes were measured together with a range of environmental variables and detailed vegetation analysis at four sites spanning 300 km latitude from Barrow to Ivotuk (Alaska). We used multiple regression modelling to identify drivers of CH4 flux, and to examine relationships between gross primary productivity (GPP), dissolved organic carbon (DOC) and CH4 fluxes. We found that a highly simplified vegetation classification consisting of just three vegetation types (wet sedge, tussock sedge and other) explained 54% of the variation in CH4 fluxes across the entire transect, performing almost as well as a more complex model including water table, sedge height and soil moisture (explaining 58% of the variation in CH4 fluxes). Substantial CH4 emissions were recorded from tussock sedges in locations even when the water table was lower than 40 cm below the surface, demonstrating the importance of plant-mediated transport. We also found no relationship between instantaneous GPP and CH4 fluxes, suggesting that models should be cautious in assuming a direct relationship between primary production and CH4 emissions. Our findings demonstrate the importance of vegetation as an integrator of processes controlling CH4 emissions in Arctic ecosystems, and provide a simplified framework for upscaling plot scale CH4 flux measurements from Arctic ecosystems
Perceived stressors of climate vulnerability across scales in the Savannah zone of Ghana: a participatory approach
Smallholder farmers in sub-Saharan Africa are confronted with climatic and non-climatic stressors. Research attention has focused on climatic stressors, such as rainfall variability, with few empirical studies exploring non-climatic stressors and how these interact with climatic stressors at multiple scales to affect food security and livelihoods. This focus on climatic factors restricts understanding of the combinations of stressors that exacerbate the vulnerability of farming households and hampers the development of holistic climate change adaptation policies. This study addresses this particular research gap by adopting a multi-scale approach to understand how climatic and non-climatic stressors vary, and interact, across three spatial scales (household, community and district levels) to influence livelihood vulnerability of smallholder farming households in the Savannah zone of northern Ghana. This study across three case study villages utilises a series of participatory tools including semi-structured interviews, key informant interviews and focus group discussions. The incidence, importance, severity and overall risk indices for stressors are calculated at the household, community, and district levels. Results show that climatic and non-climatic stressors were perceived differently; yet, there were a number of common stressors including lack of money, high cost of farm inputs, erratic rainfall, cattle destruction of crops, limited access to markets and lack of agricultural equipment that crossed all scales. Results indicate that the gender of respondents influenced the perception and severity assessment of stressors on rural livelihoods at the community level. Findings suggest a mismatch between local and district level priorities that have implications for policy and development of agricultural and related livelihoods in rural communities. Ghana’s climate change adaptation policies need to take a more holistic approach that integrates both climatic and non-climatic factors to ensure policy coherence between national climate adaptation plans and District development plans
Taxonomic diversity and identification problems of oncaeid microcopepods in the Mediterranean Sea
The species diversity of the pelagic microcopepod
family Oncaeidae collected with nets of 0.1-mm mesh
size was studied at 6 stations along a west-to-east transect
in the Mediterranean Sea down to a maximum depth of
1,000 m. A total of 27 species and two form variants have
been identified, including three new records for the
Mediterranean. In addition, about 20, as yet undescribed,
new morphospecies were found (mainly from the genera
Epicalymma and Triconia) which need to be examined
further. The total number of identified oncaeid species was
similar in the Western and Eastern Basins, but for some cooccurring
sibling species, the estimated numerical dominance
changed. The deep-sea fauna of Oncaeidae, studied
at selected depth layers between 400 m and the near-bottom
layer at >4,200 m depth in the eastern Mediterranean
(Levantine Sea), showed rather constant species numbers
down to ∼3,000 m depth. In the near-bottom layers, the
diversity of oncaeids declined and species of Epicalymma
strongly increased in numerical importance. The taxonomic
status of all oncaeid species recorded earlier in the
Mediterranean Sea is evaluated: 19 out of the 46 known
valid oncaeid species are insufficiently described, and most
of the taxonomically unresolved species (13 species) have
originally been described from this area (type locality). The
deficiencies in the species identification of oncaeids cast
into doubt the allegedly cosmopolitan distribution of some
species, in particular those of Mediterranean origin. The
existing identification problems even of well-described
oncaeid species are exemplified for the Oncaea mediacomplex,
including O. media Giesbrecht, O. scottodicarloi
Heron & Bradford-Grieve, and O. waldemari Bersano &
Boxshall, which are often erroneously identified as a single
species (O. media). The inadequacy in the species identification
of Oncaeidae, in particular those from the Atlantic
and Mediterranean, is mainly due to the lack of reliable
identification keys for Oncaeidae in warm-temperate and/or
tropical seas. Future efforts should be directed to the
construction of identification keys that can be updated
according to the latest taxonomic findings, which can be
used by the non-expert as well as by the specialist. The
adequate consideration of the numerous, as yet undescribed,
microcopepod species in the world oceans, in
particular the Oncaeidae, is a challenge for the study of the
structure and function of plankton communities as well as
for global biodiversity estimates
Early influences on cardiovascular and renal development
The hypothesis that a developmental component plays a role in subsequent disease initially arose from epidemiological studies relating birth size to both risk factors for cardiovascular disease and actual cardiovascular disease prevalence in later life. The findings that small size at birth is associated with an increased risk of cardiovascular disease have led to concerns about the effect size and the causality of the associations. However, recent studies have overcome most methodological flaws and suggested small effect sizes for these associations for the individual, but an potential important effect size on a population level. Various mechanisms underlying these associations have been hypothesized, including fetal undernutrition, genetic susceptibility and postnatal accelerated growth. The specific adverse exposures in fetal and early postnatal life leading to cardiovascular disease in adult life are not yet fully understood. Current studies suggest that both environmental and genetic factors in various periods of life may underlie the complex associations of fetal growth retardation and low birth weight with cardiovascular disease in later life. To estimate the population effect size and to identify the underlying mechanisms, well-designed epidemiological studies are needed. This review is focused on specific adverse fetal exposures, cardiovascular adaptations and perspectives for new studies. Copyrigh
Contribution mapping: a method for mapping the contribution of research to enhance its impact.
Background: At a time of growing emphasis on both the use of research and accountability, it is important for research funders, researchers and other stakeholders to monitor and evaluate the extent to which research contributes to better action for health, and find ways to enhance the likelihood that beneficial contributions are realized. Past attempts to assess research 'impact' struggle with operationalizing 'impact', identifying the users of research and attributing impact to research projects as source. In this article we describe Contribution Mapping, a novel approach to research monitoring and evaluation that aims to assess contributions instead of impacts. The approach focuses on processes and actors and systematically assesses anticipatory efforts that aim to enhance contributions, so-called alignment efforts. The approach is designed to be useful for both accountability purposes and for assisting in better employing research to contribute to better action for health.Methods: Contribution Mapping is inspired by a perspective from social studies of science on how research and knowledge utilization processes evolve. For each research project that is assessed, a three-phase process map is developed that includes the main actors, activities and alignment efforts during research formulation, production and knowledge extension (e.g. dissemination and utilization). The approach focuses on the actors involved in, or interacting with, a research project (the linked actors) and the most likely influential users, who are referred to as potential key users. In the first stage, the investigators of the assessed project are interviewed to develop a preliminary version of the process map and first estimation of research-related contributions. In the second stage, potential key-users and other informants are interviewed to trace, explore and triangulate possible contributions. In the third stage, the presence and role of alignment efforts is analyzed and the preliminary results are shared with relevant stakeholders for feedback and validation. After inconsistencies are clarified or described, the results are shared with stakeholders for learning, improvement and accountability purposes.Conclusion: Contribution Mapping provides an interesting alternative to existing methods that aim to assess research impact. The method is expected to be useful for research monitoring, single case studies, comparing multiple cases and indicating how research can better be employed to contribute to better action for health. © 2012 Kok and Schuit; licensee BioMed Central Ltd
Photodynamic detection of diseased axillary sentinel lymph node after oral application of aminolevulinic acid in patients with breast cancer
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