533 research outputs found

    Macroevolutionary diversification of glands for chemical communication in squamate reptiles

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    Chemical communication plays a central role in social, sexual and ecological interactions among animals. However, the macroevolutionary diversification of traits responsible for chemical signaling remains fundamentally unknown. Most research investigating evolutionary diversification of glands responsible for the production of chemical signals has focused on arthropods, while its study among vertebrates remains neglected. Using a global-scale dataset covering > 80% (7,904 species) of the living diversity of lizards and snakes (squamates), we investigate rates, trajectories and phylogenetic patterns of diversification of their follicular glands for chemical communication. We observed these glands in 13.66% of species, that their expression has varying phylogenetic signal among lineages, and that the crown squamate ancestor lacked follicular glands, which therefore originated and diversified subsequently during their evolutionary history. Additionally, our findings challenge the longstanding view that within squamates the Iguania are visually oriented while Scleroglossa are chemically-oriented, given that Iguania doubles Scleroglossa in the frequency of glands. Our phylogenetic analyses identified stabilizing selection as the best model describing follicular gland diversification, and revealed high rates of disparity. We provide the first global-scale analysis investigating the diversification of one of the main forms of communication among reptiles, presenting a macroevolutionary angle to questions traditionally explored at microevolutionary scale

    Use of platelet transfusions prior to lumbar punctures or epidural anaesthesia for the prevention of complications in people with thrombocytopenia

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    Background People with a low platelet count (thrombocytopenia) often require lumbar punctures or an epidural anaesthetic. Lumbar punctures can be diagnostic (haematological malignancies, epidural haematoma, meningitis) or therapeutic (spinal anaesthetic, administration of chemotherapy). Epidural catheters are placed for administration of epidural anaesthetic. Current practice in many countries is to correct thrombocytopenia with platelet transfusions prior to lumbar punctures and epidural anaesthesia, in order to mitigate the risk of serious procedure-related bleeding. However, the platelet count threshold recommended prior to these procedures varies significantly from country to country. This indicates significant uncertainty among clinicians of the correct management of these patients. The risk of bleeding appears to be low but if bleeding occurs it can be very serious (spinal haematoma). Therefore, people may be exposed to the risks of a platelet transfusion without any obvious clinical benefit. Objectives To assess the effects of different platelet transfusion thresholds prior to a lumbar puncture or epidural anaesthesia in people with thrombocytopenia (low platelet count). Search methods We searched for randomised controlled trials (RCTs) in CENTRAL (The Cochrane Library 2016, Issue 3), MEDLINE (from 1946), EMBASE (from 1974), the Transfusion Evidence Library (from 1950) and ongoing trial databases to 3 March 2016. Selection criteria We included RCTs involving transfusions of platelet concentrates, prepared either from individual units of whole blood or by apheresis, and given to prevent bleeding in people of any age with thrombocytopenia requiring insertion of a lumbar puncture needle or epidural catheter. We only included RCTs published in English. Data collection and analysis We used standard methodological procedures expected by Cochrane. Main results We identified no completed or ongoing RCTs in English. We did not exclude any completed or ongoing RCTs because they were published in another language. Authors' conclusions There is no evidence from RCTs to determine what is the correct platelet transfusion threshold prior to insertion of a lumbar puncture needle or epidural catheter. There are no ongoing registered RCTs assessing the effects of different platelet transfusion thresholds prior to the insertion of a lumbar puncture or epidural anaesthesia in people with thrombocytopenia. Any future RCT would need to be very large to detect a difference in the risk of bleeding. We would need to design a study with at least 47,030 participants to be able to detect an increase in the number of people who had major procedure-related bleeding from 1 in 1000 to 2 in 1000

    Autism as a disorder of neural information processing: directions for research and targets for therapy

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    The broad variation in phenotypes and severities within autism spectrum disorders suggests the involvement of multiple predisposing factors, interacting in complex ways with normal developmental courses and gradients. Identification of these factors, and the common developmental path into which theyfeed, is hampered bythe large degrees of convergence from causal factors to altered brain development, and divergence from abnormal brain development into altered cognition and behaviour. Genetic, neurochemical, neuroimaging and behavioural findings on autism, as well as studies of normal development and of genetic syndromes that share symptoms with autism, offer hypotheses as to the nature of causal factors and their possible effects on the structure and dynamics of neural systems. Such alterations in neural properties may in turn perturb activity-dependent development, giving rise to a complex behavioural syndrome many steps removed from the root causes. Animal models based on genetic, neurochemical, neurophysiological, and behavioural manipulations offer the possibility of exploring these developmental processes in detail, as do human studies addressing endophenotypes beyond the diagnosis itself

    Impacts of climate change on plant diseases – opinions and trends

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    There has been a remarkable scientific output on the topic of how climate change is likely to affect plant diseases in the coming decades. This review addresses the need for review of this burgeoning literature by summarizing opinions of previous reviews and trends in recent studies on the impacts of climate change on plant health. Sudden Oak Death is used as an introductory case study: Californian forests could become even more susceptible to this emerging plant disease, if spring precipitations will be accompanied by warmer temperatures, although climate shifts may also affect the current synchronicity between host cambium activity and pathogen colonization rate. A summary of observed and predicted climate changes, as well as of direct effects of climate change on pathosystems, is provided. Prediction and management of climate change effects on plant health are complicated by indirect effects and the interactions with global change drivers. Uncertainty in models of plant disease development under climate change calls for a diversity of management strategies, from more participatory approaches to interdisciplinary science. Involvement of stakeholders and scientists from outside plant pathology shows the importance of trade-offs, for example in the land-sharing vs. sparing debate. Further research is needed on climate change and plant health in mountain, boreal, Mediterranean and tropical regions, with multiple climate change factors and scenarios (including our responses to it, e.g. the assisted migration of plants), in relation to endophytes, viruses and mycorrhiza, using long-term and large-scale datasets and considering various plant disease control methods

    ‘‘Beet-ing’’ the Mountain: A Review of the Physiological and Performance Effects of Dietary Nitrate Supplementation at Simulated and Terrestrial Altitude

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    Exposure to altitude results in multiple physiological consequences. These include, but are not limited to, a reduced maximal oxygen consumption, drop in arterial oxygen saturation, and increase in muscle metabolic perturbations at a fixed sub-maximal work rate. Exercise capacity during fixed work rate or incremental exercise and time-trial performance are also impaired at altitude relative to sea-level. Recently, dietary nitrate (NO3-) supplementation has attracted considerable interest as a nutritional aid during altitude exposure. In this review, we summarise and critically evaluate the physiological and performance effects of dietary NO3- supplementation during exposure to simulated and terrestrial altitude. Previous investigations at simulated altitude indicate that NO3- supplementation may reduce the oxygen cost of exercise, elevate arterial and tissue oxygen saturation, improve muscle metabolic function, and enhance exercise capacity/ performance. Conversely, current evidence suggests that NO3- supplementation does not augment the training response at simulated altitude. Few studies have evaluated the effects of NO3- at terrestrial altitude. Current evidence indicates potential improvements in endothelial function at terrestrial altitude following NO3- supplementation. No effects of NO3- supplementation have been observed on oxygen consumption or arterial oxygen saturation at terrestrial altitude, although further research is warranted. Limitations of the present body of literature are discussed, and directions for future research are provided

    Remote pulmonary rehabilitation for interstitial lung disease: developing the model using experience-based codesign

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    Data availability statement: Data are available on reasonable request.Supplementary Data: This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content : https://bmjopenrespres.bmj.com/content/bmjresp/suppl/2024/02/21/11.1.e002061.DC1/bmjresp-2023-002061supp001_data_supplement.pdf .Background Remote delivery may improve access to pulmonary rehabilitation (PR). Existing studies are largely limited to individuals with COPD, and the interventions have lacked codesign elements to reflect the needs and experiences of people with chronic respiratory disease, their carers/families and healthcare professionals. The aim of this study was, using experience-based codesign (EBCD), to collaborate with people with interstitial lung disease (ILD), their carers/families and healthcare professionals, to codesign a remote PR programme ready for testing in a future study. Methods EBCD comprises interviews, stakeholder workshops and codesign meetings. One-to-one videorecorded interviews with purposively selected people with ILD with experience of PR, their carers/families and healthcare professionals, were edited into a 20 min film. The film was shown at three audiorecorded stakeholder feedback events to identify key themes and touchpoints, and short-list key programme components. The programme was finalised at two further codesign workshops. Results Ten people with ILD, four carers/families and seven healthcare professionals were interviewed. Participants in the codesign workshops included service-user group: n=14 and healthcare professional group: n=11; joint event: n=21. Final refinements were made with small codesign teams, one comprising three people with ILD and one carer/family member, one with five healthcare professionals. The final codesigned model is a group based, supervised programme delivered by videoconference. Key elements of programme specific to ILD include recommendations to ensure participant safety in the context of desaturation risk, dedicated time for peer support and adaption of the education programme for ILD needs, including signposting to palliative care. Conclusion In this EBCD project, a remote PR programme for people with ILD was codesigned by service-users, their carers/families and multidisciplinary healthcare professionals. Future research should explore the feasibility and acceptability of this intervention.Royal Brompton and Harefield Charity Research Management Fun

    Childhood asthma and indoor allergens in Native Americans in New York

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    BACKGROUND: The objective of this study was to assess the correlation between childhood asthma and potential risk factors, especially exposure to indoor allergens, in a Native American population. METHODS: A case-control study of St. Regis Mohawk tribe children ages 2–14 years, 25 diagnosed with asthma and 25 controls was conducted. Exposure was assessed based on a personal interview and measurement of mite and cat allergens (Der p 1, Fel d 1) in indoor dust. RESULTS: A non-significant increased risk of childhood asthma was associated with self-reported family history of asthma, childhood environmental tobacco smoke exposure, and air pollution. There was a significant protective effect of breastfeeding against current asthma in children less than 14 years (5.2 fold lower risk). About 80% of dust mite and 15% of cat allergen samples were above the threshold values for sensitization of 2 and 1 μg/g, respectively. The association between current asthma and exposure to dust mite and cat allergens was positive but not statistically significant. CONCLUSION: This research identified several potential indoor and outdoor risk factors for asthma in Mohawks homes, of which avoidance may reduce or delay the development of asthma in susceptible individuals

    Extended Longevity of Reproductives Appears to be Common in Fukomys Mole-Rats (Rodentia, Bathyergidae)

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    African mole-rats (Bathyergidae, Rodentia) contain several social, cooperatively breeding species with low extrinsic mortality and unusually high longevity. All social bathyergids live in multigenerational families where reproduction is skewed towards a few breeding individuals. Most of their offspring remain as reproductively inactive “helpers” in their natal families, often for several years. This “reproductive subdivision” of mole-rat societies might be of interest for ageing research, as in at least one social bathyergid (Ansell's mole-rats Fukomys anselli), breeders have been shown to age significantly slower than non-breeders. These animals thus provide excellent conditions for studying the epigenetics of senescence by comparing divergent longevities within the same genotypes without the inescapable short-comings of inter-species comparisons. It has been claimed that many if not all social mole-rat species may have evolved similar ageing patterns, too. However, this remains unclear on account of the scarcity of reliable datasets on the subject. We therefore analyzed a 20-year breeding record of Giant mole-rats Fukomys mechowii, another social bathyergid species. We found that breeders indeed lived significantly longer than helpers (ca. 1.5–2.2fold depending on the sex), irrespective of social rank or other potentially confounding factors. Considering the phylogenetic positions of F. mechowii and F. anselli and unpublished data on a third Fukomys-species (F. damarensis) showing essentially the same pattern, it seems probable that the reversal of the classic trade-off between somatic maintenance and sexual reproduction is characteristic of the whole genus and hence of the vast majority of social mole-rats

    Disparities in self-reported postpartum depression among Asian, Hawaiian, and Pacific Islander women in Hawai‘i: Pregnancy, Risk, Assessment, and Monitoring System (PRAMS), 2004-2007

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    Postpartum depression affects 10–20% of women and causes significant morbidity and mortality among mothers, children, families, and society, but little is known about postpartum depression among the individual Asian and Pacific Islander racial/ethnic groups. This study sought to identify the prevalence of postpartum depression among common Asian and Pacific Islander racial/ethnic groups. Data from the Hawaii Pregnancy Risk Assessment and Monitoring System (PRAMS), a population-based surveillance system on maternal behaviors and experiences before, during, and after the birth of a live infant, were analyzed from 2004 through 2007 and included 7,154 women. Questions on mood and interest in activities since giving birth were combined to create a measure of Self-reported Postpartum Depressive Symptoms (SRPDS). A series of generalized logit models with maternal race or ethnicity adjusted for other sociodemographic characteristics evaluated associations between SRPDS and an intermediate level of symptoms as possible indicators of possible SRPDS. Of all women in Hawaii with a recent live birth, 14.5% had SRPDS, and 30.1% had possible SRPDS. The following Asian and Pacific Islander racial or ethnic groups were studied and found to have higher odds of SRPDS compared with white women: Korean (adjusted odds ratio [AOR] = 2.8;95% confidence interval [CI]: 2.0–4.0), Filipino (AOR = 2.2;95% CI: 1.7–2.8), Chinese (AOR = 2.0;95% CI: 1.5–2.7), Samoan (AOR = 1.9;95% CI: 1.2–3.2), Japanese (AOR = 1.6;95% CI: 1.2–2.2), Hawaiian (AOR = 1.7;95% CI: 1.3–2.1), other Asian (AOR = 3.3;95% CI: 1.9–5.9), other Pacific Islander (AOR = 2.2;95% CI: 1.5–3.4), and Hispanic (AOR = 1.9;95% CI: 1.1–3.4). Women who had unintended pregnancies (AOR = 1.4;95% CI: 1.2–1.6), experienced intimate partner violence (AOR = 3.7;95% CI: 2.6–5.5), smoked (AOR = 1.5;95% CI: 1.2–2.0), used illicit drugs (AOR = 1.9;95% CI: 1.3–3.9), or received Women, Infant, and Children (WIC) benefits during pregnancy (AOR = 1.4;95% CI: 1.2–2.6) were more likely to have SRPDS. Several groups also were at increased risk for possible SRPDS, although this risk was not as prominent as seen with the risk for SRPDS. One in seven women reported SRPDS, and close to a third reported possible SRPDS. Messages about postpartum depression should be incorporated into current programs to improve screening, treatment, and prevention of SRPDS for women at risk

    Comprehensive geriatric assessment for people with both COPD and frailty starting pulmonary rehabilitation: a mixed-methods feasibility trial

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    Data availablility: All data requests should be submitted to M. Maddocks ([email protected]) for consideration. Access to anonymised data might be granted following investigator review.Supplementary material is available online at: https://publications.ersnet.org/content/erjor/10/4/00774-2023/DC1/embed/inline-supplementary-material-1.pdf . Please note: supplementary material is not edited by the Editorial Office, and is uploaded as it has been supplied by the author.Introduction: Many people with COPD experience frailty. Frailty increases risk of poor health outcomes, including non-completion of pulmonary rehabilitation. Integrated approaches to support people with COPD and frailty throughout and following rehabilitation are indicated. The aim of the present study was to determine the feasibility of conducting a randomised controlled trial of integrating comprehensive geriatric assessment (CGA) for people with COPD and frailty starting pulmonary rehabilitation. Methods; A multicentre mixed-methods randomised controlled feasibility trial (“Breathe Plus”; ISRCTN13051922) was carried out. People with COPD, aged ≥50 years, Clinical Frailty Scale ≥5 and referred for pulmonary rehabilitation were randomised 1:1 to usual pulmonary rehabilitation, or pulmonary rehabilitation plus CGA. Remote intervention delivery was used during COVID-19 restrictions. Outcomes (physical, psychosocial, service use) were measured at baseline, 90 and 180 days, alongside process data and qualitative interviews. Results: Recruitment stopped at 31 participants (mean±sd age 72.4±10.1 years, 68% Medical Research Council Dyspnoea Scale 4–5), due to COVID-19-related disruptions. Recruitment (46% eligible recruited) and retention (87% at 90- and 180-day follow-up) were acceptable. CGAs occurred on average 60.5 days post-randomisation (range 8–129) and prompted 46 individual care recommendations (median 3 per participant, range 0–12), 65% of which were implemented during follow-up. The most common domains addressed during CGA were nutrition and cardiovascular health. Participants valued the holistic approach of CGA but questioned the optimal time to introduce it. Conclusion: Integrating CGA alongside pulmonary rehabilitation is feasible and identifies unmet multidimensional need in people with COPD and frailty. Given challenges around timing and inclusivity, the integration of geriatric and respiratory care should not be limited to rehabilitation services.This project was funded by a National Institute for Health and Care Research (NIHR) Career Development Fellowship (CDF-2017-10-009) held by M. Maddocks. L.J. Brighton was funded by an ESRC Post-Doctoral Fellowship (ES/X005259/1). C.J. Evans was supported by a Health Education England/NIHR Senior Clinical Lectureship (ICA-SCL-2015-01-001). This research was supported by the NIHR Collaboration for Leadership in Applied Health Research and Care South London, now recommissioned as NIHR Applied Research Collaboration South London
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