1,579 research outputs found
Chemical and ecological health of white sucker (Catostomus commersoni) in Rock Creek Park, Washington, D.C., 2003-04 / by Cherie V. Miller ... [et al.] ; prepared in copoeration with the National Park Service
Several classes of chemicals that are known or suspected contaminants were found in bed sediment in Rock Creek, including polyaromatic hydrocarbons (PAHs), phthalate esters, organochlorine pesticides, dioxins and furans, trace metals and metalloids (mercury, arsenic, cadmium, chromium, cobalt, copper, lead, nickel, silver, and zinc), and polychlorinated biphenyls (total PCBs and selected aroclors). Concentrations of many of these chemicals consistently exceeded thresholdor chronic-effects guidelines for the protection of aquatic life and often exceeded probable effects levels (PELs). Exceedance of PELs was dependent on the amount of total organic carbon in the sediments. Concurrent with the collection of sediment-quality data, white sucker (Catostomus commersoni) were evaluated for gross-external and internal-organ anomalies, whole-body burdens of chemical contaminants, and gut contents to determine prey. The histopathology of internal tissues of white sucker was compared to contaminant levels in fish tissue and bed sediment. Gut contents were examined to determine preferential prey and thus potential pathways for the bioaccumulation of chemicals from bed sediments. Male and female fish were tested separately. Lesions and other necroses were observed in all fish collected during both years of sample collection, indicating that fish in Rock Creek have experienced some form of environmental stress. No direct cause and effect was determined for chemical exposure and compromised fish health, but a substantial weight of evidence indicates that white sucker, which are bottom-eeding fish and low-order consumers in Rock Creek, are experiencing some reduction in vitality, possibly due to immunosuppression. Abnormalities observed in gonads of both sexes of white sucker and observations of abnormal behavior during spawning indicated some interruption in reproductive success
Late-onset nonketotic hyperglycinemia and spinocerebellar degeneration
Investigation of a 15-year old boy with progressive optic atrophy and spinocerebellar degeneration revealed elevated plasma, cerebrospinal fluid, and urine glycine concentrations. During an oral glycine loading test, the patient's plasma glycine concentration rose to a higher level than control values, although the initial rate of rise was slower; there was no concomitant rise in the plasma serine concentration. An oral serine loading test resulted in a prompt rise of both glycine and serine serum concentrations. The renal glycine clearance was elevated, and the renal tubular glycine reabsorption was diminished. These findings of decreased intestinal uptake and increased renal tubular glycine clearance suggest that a generalized derangement of glycine entry into cells may account for the phenotypic manifestations of the disorder
Recommended from our members
COVID-19, Mental Health and Aging: A Need for New Knowledge to Bridge Science and Service.
Iodine status during pregnancy in India and related neonatal and infant outcomes
Objective:
To document iodine status in Indian pregnancies, associations with maternal diet and demographics, and offspring developmental measures.
Design:
Longitudinal study following mothers through pregnancy and offspring up to 24 months.
Setting:
Rural health-care centre (Vadu) and urban antenatal clinic (Pune) in the Maharashtra region of India.
Subjects:
Pregnant mothers at 17 (n 132) and 34 weeks’ (n 151) gestation and their infants from birth to the age of 24 months.
Results:
Median urinary iodine concentration (UIC) was 203 and 211 μg/l at 17 and 34 weeks of pregnancy, respectively (range 26–800 μg/l). Using the UIC distribution adjusted for within-person variation, extreme UIC quartiles were compared for predictors and outcomes. There was no correlation between UIC at 17 and 34 weeks, but 24 % of those with UIC in the lowest quartile at 17 weeks had UIC in the same lowest quartile at 34 weeks. Maternal educational, socio-economic status and milk products consumption (frequency) were different between the lowest and highest quartile of UIC at 34 weeks. Selected offspring developmental outcomes differed between the lowest and highest UIC quartiles (abdominal circumference at 24 months, subscapular and triceps skinfolds at 12 and 24 months). However, UIC was only a weak predictor of subscapular skinfold at 12 months and of triceps skinfold at 24 months.
Conclusions:
Median UIC in this pregnant population suggested adequate dietary provision at both gestational stages studied. Occasional high results found in spot samples may indicate intermittent consumption of iodine-rich foods. Maternal UIC had limited influence on offspring developmental outcomes
Delivering information and brief advice on alcohol (IBA) in social work and social care settings: an exploratory study
Social workers and practitioners working in social care are potentially key players in the prevention of alcohol-related harm and harm reduction for people using services and their carers. This requires attention to workforce development alongside the selection of appropriate tools to support prevention strategies. We report findings from a UK exploratory study into the potential of using Identification and Brief Advice (IBA) as a tool for screening and prevention in social work and social care settings. Thirty-six social workers and social care practitioners attended one of two training workshops on IBA in the South East of England. Pre and post-workshop surveys (n = 35 and n = 20, respectively) and four post-workshop focus groups (n = 36) were conducted with participants to explore the application of IBA taking into account the paradigmatic shift towards prevention and holistic approaches indicated in recent UK legislation and policy. Four themes emerged from the findings: (1) perceptions of the social work/social care role in responding to alcohol problems, (2) ethical concerns, (3) time conflicts and problems of delivering IBA and (4) the role of training. Further studies are needed to evaluate the effectiveness of motivational techniques and tools that social workers can use to promote preventative practise for alcohol-related harm. Different strategies are required to engage and support those working in social care to increase proactive engagement with problematic alcohol use in everyday practise settings
Recommended from our members
Barriers and facilitators to adherence to group exercise in institutionalized older people living with dementia: a systematic review
Objectives
Research suggests targeted exercise is important for people living with dementia, especially those living in residential care. The aim of this review was to collect and synthesize evidence on the known barriers and facilitators to adherence to group exercise of institutionalized older people living with dementia.
Methods
We searched all available electronic databases. Additionally, we searched trial registries (clinicaltrial.gov, and WHO ICTRP) for ongoing studies. We searched for and included papers from January 1990 until September 2017 in any language. We included randomized, non-randomized trials. Studies were not eligible if participants were either healthy older people or people suffering from dementia but not living in an institution. Studies were also excluded if they were not focused on barriers and facilitators to adherence to group exercise.
Results
Using narrative analysis, we identified the following themes for barriers: bio-medical reasons and mental wellbeing and physical ability, relationships dynamics, and socioeconomic reasons. The facilitators were grouped under the following thematic frames: bio-medical benefits and benefits related to physical ability, feelings and emotions and confidence improvements, therapist and group relationships dynamics and activity related reasons.
Conclusions
We conclude that institutionalized older people living with dementia, even those who are physically frail, incontinent and/or have mild dementia can demonstrate certain level of exercise adherence, and therefore can respond positively to exercise programs. Tailored, individually-adjusted and supported physical activity, led by a knowledgeable, engaging and well communicating therapist/facilitator improves the adherence to group exercise interventions of institutionalized older people living with dementia
A longitudinal investigation of repressive coping and ageing
This is an Accepted Manuscript of an article published by Taylor & Francis in Aging & Mental Health on October 2016, available online: http://www.tandfonline.com/doi/full/10.1080/13607863.2015.1060941.Two studies investigated the possibility that repressive coping is more prevalent in older adults and that this represents a developmental progression rather than a cohort effect. Study 1 examined repressive coping and mental health cross-sectionally in young and old adults. Study 2 examined whether there was a developmental progression of repressive coping prevalence rates in a longitudinal sample of older adults.Peer reviewedFinal Accepted Versio
Post-mortem brain analyses of the Lothian Birth Cohort 1936:Extending lifetime cognitive and brain phenotyping to the level of the synapse
INTRODUCTION: Non-pathological, age-related cognitive decline varies markedly between individuals andplaces significant financial and emotional strain on people, their families and society as a whole.Understanding the differential age-related decline in brain function is critical not only for the development oftherapeutics to prolong cognitive health into old age, but also to gain insight into pathological ageing suchas Alzheimer’s disease. The Lothian Birth Cohort of 1936 (LBC1936) comprises a rare group of people forwhom there are childhood cognitive test scores and longitudinal cognitive data during older age, detailedstructural brain MRI, genome-wide genotyping, and a multitude of other biological, psycho-social, andepidemiological data. Synaptic integrity is a strong indicator of cognitive health in the human brain;however, until recently, it was prohibitively difficult to perform detailed analyses of synaptic and axonalstructure in human tissue sections. We have adapted a novel method of tissue preparation at autopsy toallow the study of human synapses from the LBC1936 cohort in unprecedented morphological andmolecular detail, using the high-resolution imaging techniques of array tomography and electronmicroscopy. This allows us to analyze the brain at sub-micron resolution to assess density, proteincomposition and health of synapses. Here we present data from the first donated LBC1936 brain andcompare our findings to Alzheimer’s diseased tissue to highlight the differences between healthy andpathological brain ageing. RESULTS: Our data indicates that compared to an Alzheimer’s disease patient, the cognitively normalLBC1936 participant had a remarkable degree of preservation of synaptic structures. However,morphological and molecular markers of degeneration in areas of the brain associated with cognition(prefrontal cortex, anterior cingulate cortex, and superior temporal gyrus) were observed. CONCLUSIONS: Our novel post-mortem protocol facilitates high-resolution neuropathological analysis of the well-characterized LBC1936 cohort, extending phenotyping beyond cognition and in vivo imaging to nowinclude neuropathological changes, at the level of single synapses. This approach offers an unprecedentedopportunity to study synaptic and axonal integrity during ageing and how it contributes to differences in agerelatedcognitive change. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s40478-015-0232-0) contains supplementary material, which is available to authorized users
A mouse-human phase 1 co-clinical trial of a protease-activated fluorescent probe for imaging cancer
Local recurrence is a common cause of treatment failure for patients with solid tumors. Intraoperative detection of microscopic residual cancer in the tumor bed could be used to decrease the risk of a positive surgical margin, reduce rates of reexcision, and tailor adjuvant therapy. We used a protease-activated fluorescent imaging probe, LUM015, to detect cancer in vivo in a mouse model of soft tissue sarcoma (STS) and ex vivo in a first-in-human phase 1 clinical trial. In mice, intravenous injection of LUM015 labeled tumor cells, and residual fluorescence within the tumor bed predicted local recurrence. In 15 patients with STS or breast cancer, intravenous injection of LUM015 before surgery was well tolerated. Imaging of resected human tissues showed that fluorescence from tumor was significantly higher than fluorescence from normal tissues. LUM015 biodistribution, pharmacokinetic profiles, and metabolism were similar in mouse and human subjects. Tissue concentrations of LUM015 and its metabolites, including fluorescently labeled lysine, demonstrated that LUM015 is selectively distributed to tumors where it is activated by proteases. Experiments in mice with a constitutively active PEGylated fluorescent imaging probe support a model where tumor-selective probe distribution is a determinant of increased fluorescence in cancer. These co-clinical studies suggest that the tumor specificity of protease-activated imaging probes, such as LUM015, is dependent on both biodistribution and enzyme activity. Our first-in-human data support future clinical trials of LUM015 and other protease-sensitive probes
The future of successful aging in Alaska
Background. There is a paucity of research on Alaska Natives and their views on whether or not they believe they will age successfully in their home and community. There is limited understanding of aging experiences across generations. Objective. This research explores the concept of successful aging from an urban Alaska Native perspective and explores whether or not they believe they will achieve a healthy older age. Design. A cultural consensus model (CCM) approach was used to gain a sense of the cultural understandings of aging among young Alaska Natives aged 50 years and younger. Results. Research findings indicate that aging successfully is making the conscious decision to live a clean and healthy life, abstaining from drugs and alcohol, but some of Alaska Natives do not feel they will age well due to lifestyle factors. Alaska Natives see the inability to age well as primarily due to the decrease in physical activity, lack of availability of subsistence foods and activities, and the difficulty of living a balanced life in urban settings. Conclusions. This research seeks to inform future studies on successful aging that incorporates the experiences and wisdom of Alaska Natives in hopes of developing an awareness of the importance of practicing a healthy lifestyle and developing guidelines to assist others to age well
- …
