New biological models are incorporating the realistic processes underlying biological responses to climate change and other human-caused disturbances. However, these more realistic models require ...detailed information, which is lacking for most species on Earth. Current monitoring efforts mainly document changes in biodiversity, rather than collecting the mechanistic data needed to predict future changes. We describe and prioritize the biological information needed to inform more realistic projections of species' responses to climate change. We also highlight how trait-based approaches and adaptive modeling can leverage sparse data to make broader predictions. We outline a global effort to collect the data necessary to better understand, anticipate, and reduce the damaging effects of climate change on biodiversity.
Community composition in a given landscape is a complex product of the constituent species' niche requirements, geographic connectivity, environmental properties, species interactions and drift. In ...this study, we examined niche use of 16 cladoceran species in 81 zooplankton communities that inhabit environmentally variable sites along a strong urbanization gradient. We tested to what extent niche shifts occurred along the urbanization gradient. We also quantified to what extent niche overlap can explain co‐occurrence patterns and tested whether alternative processes such as dispersal limitation or environmental heterogeneity impact co‐occurrence patterns. Niche use in the study region was size‐mediated, with larger species preferring nutrient‐rich environments while smaller species were more specialized on distinct niche axes. Our analyses also revealed that mainly generalist species were able to establish in urban sites. While the average niche position for most species was conserved from rural to urban sites, the niches of those species occurring in both rural and urban areas remain partly unfilled in the urban populations. We observed that a relatively small proportion (13%) of species pairs co‐occurred more or less often than expected by chance, but also that niche overlap was the only predictor that was strongly and significantly associated with co‐occurrence scores in our study. While most of these species pairs showed evidence for a role of environmental filtering, a few common, generalist species pairs displayed segregated co‐occurrence patterns and high niche overlap, suggesting a role of limiting similarity relationships as well. Our study highlights the damaging effects on biodiversity of urbanization through biotic homogenization benefitting generalist species, as well as the difficulty species may face in occupying available niche space in urbanized habitats.
Alzheimer's disease (AD) is the most common form of dementia, and it affects more women than men. Mitochondrial dysfunction (MD) plays a key role in AD, and it is detectable at an early stage of the ...degenerative process in peripheral tissues, such as peripheral mononuclear blood cells (PBMCs). However, whether these changes are also reflected in cerebral energy metabolism and whether sex-specific differences in mitochondrial function occur are not clear. Therefore, we estimated the correlation between mitochondrial function in PBMCs and brain energy metabolites and examined sex-specific differences in healthy participants to elucidate these issues.
The current pilot study included 9 male and 15 female healthy adults (mean age 30.8 ± 7.1 years). Respiration and activity of mitochondrial respiratory complexes were measured using a Clarke-electrode (Oxygraph-2k system), and adenosine triphosphate (ATP) levels were determined using a bioluminescence-based assay in isolated PBMCs. Citrate synthase activity as a mitochondrial marker was measured using a photometric assay. Concentrations of brain energy metabolites were quantified in the same individuals using
H-magnetic resonance spectroscopy (MRS).
We detected sex-associated differences in mitochondrial function. Mitochondrial complexes I, I+II, and IV and uncoupled respiration and electron transport system (ETS) capacity in PBMCs isolated from blood samples of females were significantly (p < 0.05; p < 0.01) higher compared to males. ATP levels in the PBMCs of female participants were approximately 10% higher compared to males. Citrate synthase (CS) activity, a marker of mitochondrial content, was significantly (p < 0.05) higher in females compared to males. Sex-associated differences were also found for brain metabolites. The N-acetylaspartate (NAA) concentration was significantly higher in female participants compared to males in targeted regions. This difference was observed in white matter (WM) and an area with a high percentage (> 50%) of gray matter (GM) (p < 0.05; p < 0.01). The effect sizes indicated a strong influence of sex on these parameters. Sex-associated differences were found in PBMCs and brain, but the determined parameters were not significantly correlated.
Our study revealed sex-associated differences in mitochondrial function in healthy participants. The underlying mechanisms must be elucidated in more detail, but our study suggests that mitochondrial function in PBMCs is a feasible surrogate marker to detect differences in mitochondrial function and energy metabolism in humans and it underscores the necessity of sex-specific approaches in therapies that target mitochondrial dysfunction.
The growth hormone (GH) secretagogue receptor (GHSR) was cloned as the target of a family of synthetic molecules endowed with GH release properties. As shown recently through in vitro means, this ...receptor displays a constitutive activity whose clinical relevance is unknown. Although pharmacological studies have demonstrated that its endogenous ligand--ghrelin--stimulates, through the GHSR, GH secretion and appetite, the physiological importance of the GHSR-dependent pathways remains an open question that gives rise to much controversy. We report the identification of a GHSR missense mutation that segregates with short stature within 2 unrelated families. This mutation, which results in decreased cell-surface expression of the receptor, selectively impairs the constitutive activity of the GHSR, while preserving its ability to respond to ghrelin. This first description, to our knowledge, of a functionally significant GHSR mutation, which unveils the critical importance of the GHSR-associated constitutive activity, discloses an unusual pathogenic mechanism of growth failure in humans.
In this report, we present the results of a multicenter study to test analytic and diagnostic performance of soluble forms of amyloid precursor proteins alpha and beta (sAPP alpha and sAPP beta) in ...the cerebrospinal fluid (CSF) of patients with different forms of dementing conditions. CSF samples were collected from 188 patients with early dementia (mini-mental state examination >or=20 in majority of cases) and mild cognitive impairment (MCI) in 12 gerontopsychiatric centers, and the clinical diagnoses were supported by neurochemical dementia diagnostic (NDD) tools: CSF amyloid beta peptides, Tau and phospho-Tau. sAPP alpha and sAPP beta were measured with multiplexing method based on electrochemiluminescence. sAPP alpha and sAPP beta CSF concentrations correlated with each other with very high correlation ratio (R=0.96, P<0.001). We observed highly significantly increased sAPP alpha and sAPP beta CSF concentrations in patients with NDD characteristic for Alzheimer's disease (AD) compared to those with NDD negative results. sAPP alpha and sAPP beta highly significantly separated patients with AD, whose diagnosis was supported by NDD findings (sAPP alpha: cutoff, 117.4 ng ml(-1), sensitivity, 68%, specificity, 85%, P<0.001; sAPP beta: cutoff, 181.8 ng ml(-1), sensitivity, 75%, specificity, 85%, P<0.001), from the patients clinically assessed as having other dementias and supported by NDD untypical for AD. We conclude sAPP alpha and sAPP beta might be regarded as novel promising biomarkers supporting the clinical diagnosis of AD.
The modern rectal cancer treatment paradigm offers additional opportunities for organ preservation, most notably via total neoadjuvant therapy (TNT) and consideration for a watch-and-wait (WW) ...surveillance-only approach. A major barrier to widespread implementation of a WW approach to rectal cancer is the potential discordance between a clinical complete response (cCR) and a pathologic complete response (pCR). In the pre-TNT era, the identification of predictors of pCR after neoadjuvant therapy had been previously studied. However, the last meta-analysis to assess the summative evidence on this important treatment decision point predates the acceptance and dissemination of TNT strategies. The purpose of this systematic review was to assess preoperative predictors of pCR after TNT to guide the ideal selection criteria for WW in the current era. An exhaustive literature review was performed and the electronic databases Embase, Ovid, MEDLINE, PubMed, and Cochrane were comprehensively searched up to 27 June 2023. Search terms and their combinations included "rectal neoplasms", "total neoadjuvant therapy", and "pathologic complete response". Only studies in English were included. Randomized clinical trials or prospective/retrospective cohort studies of patients with clinical stage 2 or 3 rectal adenocarcinoma who underwent at least 8 weeks of neoadjuvant chemotherapy in addition to chemoradiotherapy with pCR as a measured study outcome were included. In this systematic review, nine studies were reviewed for characteristics positively or negatively associated with pCR or tumor response after TNT. The results were qualitatively grouped into four categories: (1) biochemical factors; (2) clinical factors; (3) patient demographics; and (4) treatment sequence for TNT. The heterogeneity of studies precluded meta-analysis. The level of evidence was low to very low. There is minimal data to support any clinicopathologic factors that either have a negative or positive relationship to pCR and tumor response after TNT. Additional data from long-term trials using TNT is critical to better inform those considering WW approaches following a cCR.
To compare cued recall measures with other memory and nonmemory tests regarding their association with a biomarker profile indicative of Alzheimer disease (AD) in CSF among patients with mild ...cognitive impairment (MCI).
Data were obtained by the German Dementia Competence Network. A total of 185 memory clinic patients fulfilling broad criteria for MCI (1 SD deficit in memory tests or in nonmemory tests) were assessed with an extended neuropsychological battery, which included the Free and Cued Selective Reminding Test (FCSRT), the word list learning task from the Consortium to Establish a Registry for Alzheimer's Disease neuropsychological battery (CERAD-NP), and the Logical Memory (LM) paragraph recall test from the Wechsler Memory Scale-Revised. CSF was obtained from all patients.
A total of 74 out of 185 subjects with MCI (40%) had a CSF profile consistent with AD (Aβ(1-42)/tau ratio; CSF AD+ group). FCSRT measures reflecting both free and cued recall discriminated best between CSF AD+ and CSF AD- patients, and significantly improved CSF AD classification accuracy, as compared with CERAD delayed recall and LM delayed recall.
Cued recall deficits are most closely associated with CSF biomarkers indicative of AD in subjects with MCI. This novel finding complements results from prospective clinical studies and provides further empirical support for cued recall as a specific indicator of prodromal AD, in line with recently proposed research criteria.
There is mounting evidence that aerobic exercise has a positive effect on cognitive functions in older adults. To date, little is known about the neurometabolic and molecular mechanisms underlying ...this positive effect. The present study used magnetic resonance spectroscopy and quantitative MRI to systematically explore the effects of physical activity on human brain metabolism and grey matter (GM) volume in healthy aging. This is a randomised controlled assessor-blinded two-armed trial (n=53) to explore exercise-induced neuroprotective and metabolic effects on the brain in cognitively healthy older adults. Participants (age >65) were allocated to a 12-week individualised aerobic exercise programme intervention (n=29) or a 12-week waiting control group (n=24). The main outcomes were the change in cerebral metabolism and its association to brain-derived neurotrophic factor (BDNF) levels as well as changes in GM volume. We found that cerebral choline concentrations remained stable after 12 weeks of aerobic exercise in the intervention group, whereas they increased in the waiting control group. No effect of training was seen on cerebral N-acetyl-aspartate concentrations, nor on markers of neuronal energy reserve or BDNF levels. Further, we observed no change in cortical GM volume in response to aerobic exercise. The finding of stable choline concentrations in the intervention group over the 3 month period might indicate a neuroprotective effect of aerobic exercise. Choline might constitute a valid marker for an effect of aerobic exercise on cerebral metabolism in healthy aging.
Train the trainer in dementia care Franzmann, J.; Haberstroh, J.; Pantel, J.
Zeitschrift für Gerontologie und Geriatrie,
04/2016, Letnik:
49, Številka:
3
Journal Article
Recenzirano
Background
Improvement of communication skills in nursing home staff is key to provide better care for dementia patients and decrease occupational mental stress.
Objectives
An innovative ...train-the-trainer program to improve and maintain professional caregivers’ social competencies in nursing home dementia care is described.
Design and methods
Over a period of 6 months, a group of 6 senior staff members were qualified as program trainers (multiplicators) for the TANDEM training program, which qualified them to design, deliver, and evaluate training sessions that foster specific social competencies in dementia care. In a subsequent intervention study with 116 geriatric caregivers in 14 nursing homes, training was provided either by multiplicators (intervention group) or directly by project coworkers (control group).
Results
Participants in both groups improved their dementia-specific communication skills. In a follow-up survey, the intervention group also reported lasting reductions in mental stressors at work (p < 0.05) and occupational mental stress (p < 0.01) compared with the control group.
Conclusions
The qualification of staff members in German nursing homes to be multiplicators for the TANDEM train-the-trainer program for dementia-specific communication skills has a beneficial influence on social competencies, mental stressors at work, and occupational mental stress of staff who care for dementia patients and may contribute to a sustainable implementation of dementia-specific social competencies.
Postoperative hypocalcemia is the most common complication after thyroidectomy. Postoperative supplementation with calcium and calcitriol reduces its occurrence; however, prophylactic preoperative ...supplementation has not been studied systematically. The primary objective of this study was to determine whether pre- and postoperative calcium and calcitriol supplementation reduces postoperative hypocalcemia after total thyroidectomy compared with postoperative supplementation alone.
We conducted a single-institution prospective randomized trial enrolling 82 patients undergoing total thyroidectomy from July 2017 through May 2019. Those undergoing partial thyroidectomy or concurrent planned parathyroidectomy were excluded. The intervention group started calcitriol 0.25 μg po bid and calcium carbonate 1,500 mg po tid 5 days preoperatively and continued postoperatively. The control group started these medications postoperatively. The primary end point was clinical or biochemical hypocalcemia. Secondary outcomes were postoperative calcium levels, need for intervention, length of stay, and readmission.
Thirty-eight patients were randomized to the intervention group and 44 to the control group. There were 12 episodes of hypocalcemia; 5 (13.2%) in the intervention and 7 (15.9%) in the control group (p = 0.76). No differences were found in secondary outcomes; including postoperative calcium levels at each measured time point, need for intervention (n = 10 26.3%, n = 15 34.1%; p = 0.48), length of stay (mean SD 32.3 15.6 hours, 30.7 10.5 hours; p = 0.6), or readmissions (n = 0 0.0%, n = 3 6.8%; p = 0.24).
Starting supplementation with calcium and calcitriol preoperatively does not reduce postoperative hypocalcemia compared with postoperative supplementation alone after total thyroidectomy. These findings do not support the practice of routine calcium and calcitriol supplementation before total thyroidectomy.
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