RESUMEN
The execution of goal-oriented behaviours requires a spatially coherent alignment between sensory and motor maps. The current model for sensorimotor transformation in the superior colliculus relies on the topographic mapping of static spatial receptive fields onto movement endpoints1-6. Here, to experimentally assess the validity of this canonical static model of alignment, we dissected the visuo-motor network in the superior colliculus and performed in vivo intracellular and extracellular recordings across layers, in restrained and unrestrained conditions, to assess both the motor and the visual tuning of individual motor and premotor neurons. We found that collicular motor units have poorly defined visual static spatial receptive fields and respond instead to kinetic visual features, revealing the existence of a direct alignment in vectorial space between sensory and movement vectors, rather than between spatial receptive fields and movement endpoints as canonically hypothesized. We show that a neural network built according to these kinetic alignment principles is ideally placed to sustain ethological behaviours such as the rapid interception of moving and static targets. These findings reveal a novel dimension of the sensorimotor alignment process. By extending the alignment from the static to the kinetic domain this work provides a novel conceptual framework for understanding the nature of sensorimotor convergence and its relevance in guiding goal-directed behaviours.
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Modelos Neurológicos , Movimiento , Colículos Superiores , Percepción Visual , Animales , Femenino , Masculino , Objetivos , Cinética , Neuronas Motoras/fisiología , Movimiento/fisiología , Red Nerviosa/citología , Red Nerviosa/fisiología , Estimulación Luminosa , Desempeño Psicomotor/fisiología , Reproducibilidad de los Resultados , Colículos Superiores/citología , Colículos Superiores/fisiología , Percepción Visual/fisiologíaRESUMEN
RATIONALE & OBJECTIVE: Optimal approaches to treat secondary hyperparathyroidism (SHPT) in patients on maintenance hemodialysis (HD) have yet to be established in randomized controlled trials (RCTs). STUDY DESIGN: Two observational clinical trial emulations. SETTING & PARTICIPANTS: Both emulations included adults receiving in-center HD from a national dialysis organization. The patients who had SHPT in the period between 2009 and 2014, were insured for≥180 days by Medicare as primary payer, and did not have contraindications or poor health status limiting theoretical trial participation. EXPOSURE: The parathyroid hormone (PTH) Target Trial emulation included patients with new-onset SHPT (first PTH 300-600pg/mL), with 2 arms defined as up-titration of either vitamin D sterols or cinacalcet within 30 days (lower target) or no up-titration (higher target). The Agent Trial emulation included patients with a PTH≥300 pg/mL while on≥6µg weekly of vitamin D sterol (paricalcitol equivalent dose) and no prior history of cinacalcet. The 2 arms were defined by the first dose or agent change within 30 days (vitamin D-favoring [vitamin-D was up-titrated] vs cinacalcet-favoring [cinacalcet was added] vs nondefined [neither applies]). Multiple trials per patient were allowed in trial 2. OUTCOME: The primary outcome was all-cause death over 24 months; secondary outcomes included cardiovascular (CV) hospitalization or the composite of CV hospitalization or death. ANALYTICAL APPROACH: Pooled logistic regression. RESULTS: There were 1,152 patients in the PTH Target Trial (635 lower target and 517 higher target). There were 2,726 unique patients with 6,727 patient trials in the Agent Trial (6,268 vitamin D-favoring trials and 459 cinacalcet-favoring trials). The lower PTH target approach was associated with reduced adjusted hazard of death (HR, 0.71 [95% CI, 0.52-0.93]), CV hospitalization (HR, 0.78 [95% CI, 0.63-0.98]), and their composite (HR, 0.74 [95% CI, 0.61-0.89]). The cinacalcet-favoring approach demonstrated lower adjusted hazard of death compared to the vitamin D-favoring approach (HR, 0.79 [95% CI, 0.62-0.99]), but not of CV hospitalization or the composite outcome. LIMITATIONS: Potential for residual confounding; low use of cinacalcet with low power. CONCLUSIONS: SHPT management that is focused on lower PTH targets may lower mortality and CV disease in patients receiving HD. These findings should be confirmed in a pragmatic randomized trial. PLAIN-LANGUAGE SUMMARY: Optimal approaches to treat secondary hyperparathyroidism (SHPT) have not been established in randomized controlled trials. Data from a national dialysis organization was used to identify patients with SHPT in whom escalated treatment may be indicated. The approach to treatment was defined based on observed upward titration of SHPT-controlling medications: earlier titration (lower target) versus delayed titration (higher target); and the choice of medication (cinacalcet vs vitamin D sterols). In the first trial emulation, we estimated a 29% lower rate of death and 26% lower rate of cardiovascular disease or death for patients managed with a lower versus higher target approach. Cinacalcet versus vitamin D-favoring approaches were not consistently associated with outcomes in the second trial emulation. This observational study suggests the need for additional clinical trials of SHPT treatment intensity.
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Enfermedades Cardiovasculares , Hiperparatiroidismo Secundario , Adulto , Humanos , Cinacalcet/uso terapéutico , Naftalenos/uso terapéutico , Resultado del Tratamiento , Hiperparatiroidismo Secundario/tratamiento farmacológico , Hiperparatiroidismo Secundario/etiología , Vitamina D/uso terapéutico , Diálisis Renal/efectos adversos , Vitaminas/uso terapéutico , Hormona Paratiroidea , Esteroles/uso terapéutico , Enfermedades Cardiovasculares/etiologíaRESUMEN
RATIONALE & OBJECTIVE: The life expectancy of patients treated with maintenance hemodialysis (MHD) is heterogeneous. Knowledge of life-expectancy may focus care decisions on near-term versus long-term goals. The current tools are limited and focus on near-term mortality. Here, we develop and assess potential utility for predicting near-term mortality and long-term survival on MHD. STUDY DESIGN: Predictive modeling study. SETTING & PARTICIPANTS: 42,351 patients contributing 997,381 patient months over 11 years, abstracted from the electronic health record (EHR) system of midsize, nonprofit dialysis providers. NEW PREDICTORS & ESTABLISHED PREDICTORS: Demographics, laboratory results, vital signs, and service utilization data available within dialysis EHR. OUTCOME: For each patient month, we ascertained death within the next 6 months (ie, near-term mortality) and survival over more than 5 years during receipt of MHD or after kidney transplantation (ie, long-term survival). ANALYTICAL APPROACH: We used least absolute shrinkage and selection operator logistic regression and gradient-boosting machines to predict each outcome. We compared these to time-to-event models spanning both time horizons. We explored the performance of decision rules at different cut points. RESULTS: All models achieved an area under the receiver operator characteristic curve of≥0.80 and optimal calibration metrics in the test set. The long-term survival models had significantly better performance than the near-term mortality models. The time-to-event models performed similarly to binary models. Applying different cut points spanning from the 1st to 90th percentile of the predictions, a positive predictive value (PPV) of 54% could be achieved for near-term mortality, but with poor sensitivity of 6%. A PPV of 71% could be achieved for long-term survival with a sensitivity of 67%. LIMITATIONS: The retrospective models would need to be prospectively validated before they could be appropriately used as clinical decision aids. CONCLUSIONS: A model built with readily available clinical variables to support easy implementation can predict clinically important life expectancy thresholds and shows promise as a clinical decision support tool for patients on MHD. Predicting long-term survival has better decision rule performance than predicting near-term mortality. PLAIN-LANGUAGE SUMMARY: Clinical prediction models (CPMs) are not widely used for patients undergoing maintenance hemodialysis (MHD). Although a variety of CPMs have been reported in the literature, many of these were not well-designed to be easily implementable. We consider the performance of an implementable CPM for both near-term mortality and long-term survival for patients undergoing MHD. Both near-term and long-term models have similar predictive performance, but the long-term models have greater clinical utility. We further consider how the differential performance of predicting over different time horizons may be used to impact clinical decision making. Although predictive modeling is not regularly used for MHD patients, such tools may help promote individualized care planning and foster shared decision making.
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Fallo Renal Crónico , Diálisis Renal , Humanos , Diálisis Renal/mortalidad , Diálisis Renal/métodos , Masculino , Femenino , Persona de Mediana Edad , Fallo Renal Crónico/terapia , Fallo Renal Crónico/mortalidad , Anciano , Esperanza de Vida , Tasa de Supervivencia/tendencias , Factores de Tiempo , Medición de Riesgo/métodos , Estudios RetrospectivosRESUMEN
RATIONALE & OBJECTIVE: Prescribing psychoactive medications for patients with kidney disease is common, but for patients receiving dialysis, some medications may be inappropriate. We evaluated the association of coprescribing gabapentinoids and other psychoactive potentially inappropriate medications (PPIMs) (e.g., sedatives, opioids) with altered mental status (AMS) and falls, and whether the associations are modified by frailty. STUDY DESIGN: Observational cohort study. SETTING: & Participants: Adults receiving dialysis represented in the United States Renal Data System who had an active gabapentinoid prescription and no other PPIM prescriptions in the prior 6 months. EXPOSURE: PPIM coprescribing, or the presence of overlapping prescriptions of a gabapentinoid and ≥1 additional PPIM. OUTCOMES: Acute care visits for AMS and injurious falls. ANALYTICAL APPROACH: Prentice-Williams-Petersen Gap Time models estimated the association between PPIM coprescribing and each outcome, adjusting for demographics, comorbidities, and frailty (assessed by a validated frailty index (FI)). Each model tested for interaction between PPIM coprescribing and frailty. RESULTS: Overall, PPIM coprescribing was associated with increased hazard of AMS (HR: 1.66 [95% CI 1.44, 1.92]) and falls (HR: 1.55 [95% CI 1.36, 1.77]). Frailty significantly modified the effect of PPIM coprescribing on the hazard of AMS (interaction p=0.01), but not falls. Among individuals with low frailty (FI=0.15), the hazard ratio for AMS with PPIM co-prescribing was 2.14 (95% CI: 1.69, 2.71); while for individuals with severe frailty (FI=0.34), the hazard ratio for AMS with PPIM coprescribing was 1.64 (95% CI: 1.42, 1.89). Individuals with PPIM coprescribing and severe frailty (FI =0.34) had the highest hazard of AMS [HR 4.04 (95% CI: 3.20, 5.10)] and falls [HR 2.77 (95% CI: 2.27, 3.38)] compared to non-frail individuals without PPIM coprescribing. LIMITATIONS: Outcome ascertainment bias; residual confounding. CONCLUSIONS: Compared to gabapentinoid prescriptions alone, PPIM coprescribing was associated with an increased risk of AMS and falls. Clinicians should consider these risks when coprescribing PPIMs to patients receiving dialysis.
RESUMEN
A minuscule fraction of the Earth's paleobiological diversity is preserved in the geological record as fossils. What plant remnants have withstood taphonomic filtering, fragmentation, and alteration in their journey to become part of the fossil record provide unique information on how plants functioned in paleo-ecosystems through their traits. Plant traits are measurable morphological, anatomical, physiological, biochemical, or phenological characteristics that potentially affect their environment and fitness. Here, we review the rich literature of paleobotany, through the lens of contemporary trait-based ecology, to evaluate which well-established extant plant traits hold the greatest promise for application to fossils. In particular, we focus on fossil plant functional traits, those measurable properties of leaf, stem, reproductive, or whole plant fossils that offer insights into the functioning of the plant when alive. The limitations of a trait-based approach in paleobotany are considerable. However, in our critical assessment of over 30 extant traits we present an initial, semi-quantitative ranking of 26 paleo-functional traits based on taphonomic and methodological criteria on the potential of those traits to impact Earth system processes, and for that impact to be quantifiable. We demonstrate how valuable inferences on paleo-ecosystem processes (pollination biology, herbivory), past nutrient cycles, paleobiogeography, paleo-demography (life history), and Earth system history can be derived through the application of paleo-functional traits to fossil plants.
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Ecosistema , Fósiles , Ecología , Plantas , FenotipoRESUMEN
The distribution of forest cover alters Earth surface mass and energy exchange and is controlled by physiology, which determines plant environmental limits. Ancient plant physiology, therefore, likely affected vegetation-climate feedbacks. We combine climate modeling and ecosystem-process modeling to simulate arboreal vegetation in the late Paleozoic ice age. Using GENESIS V3 global climate model simulations, varying pCO2, pO2, and ice extent for the Pennsylvanian, and fossil-derived leaf C:N, maximum stomatal conductance, and specific conductivity for several major Carboniferous plant groups, we simulated global ecosystem processes at a 2° resolution with Paleo-BGC. Based on leaf water constraints, Pangaea could have supported widespread arboreal plant growth and forest cover. However, these models do not account for the impacts of freezing on plants. According to our interpretation, freezing would have affected plants in 59% of unglaciated land during peak glacial periods and 73% during interglacials, when more high-latitude land was unglaciated. Comparing forest cover, minimum temperatures, and paleo-locations of Pennsylvanian-aged plant fossils from the Paleobiology Database supports restriction of forest extent due to freezing. Many genera were limited to unglaciated land where temperatures remained above -4 °C. Freeze-intolerance of Pennsylvanian arboreal vegetation had the potential to alter surface runoff, silicate weathering, CO2 levels, and climate forcing. As a bounding case, we assume total plant mortality at -4 °C and estimate that contracting forest cover increased net global surface runoff by up to 6.1%. Repeated freezing likely influenced freeze- and drought-tolerance evolution in lineages like the coniferophytes, which became increasingly dominant in the Permian and early Mesozoic.
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Árboles/fisiología , Clima , Cambio Climático , Modelos Climáticos , Conservación de los Recursos Naturales/métodos , Ecosistema , Bosques , Fósiles , Hidrología , PlantasRESUMEN
The excretory mechanisms of stenohaline marine osmoconforming crabs are often compared to those of the more extensively characterized euryhaline osmoregulating crabs. These comparisons may have limitations, given that unlike euryhaline brachyurans the gills of stenohaline marine osmoconformers possess ion-leaky paracellular pathways and lack the capacity to undergo ultrastructural changes that can promote ion-transport processes in dilute media. Furthermore, the antennal glands of stenohaline marine osmoconformers are poorly characterized making it difficult to determine what role urinary processes play in excretion. In the presented study, ammonia excretory processes as well as related acid-base equivalent transport rates and mechanisms were investigated in the Dungeness crab, Metacarcinus magister - an economically valuable stenohaline marine osmoconforming crab. Isolated and perfused gills were found to predominantly eliminate ammonia through a microtubule network-dependent active NH4+ transport mechanism that is likely performed by cells lining the arterial pockets of the gill lamella where critical Na+/K+-ATPase detection was observed. The V-type H+-ATPase - a vital component to transbranchial ammonia excretion mechanisms of euryhaline crabs - was not found to contribute significantly to ammonia excretion; however, this may be due to the transporter's unexpected apical localization. Although unconnected to ammonia excretion rates, a membrane-bound isoform of carbonic anhydrase was localized to the apical and basolateral membranes of lamella suited for respiration. Urine was found to contain significantly less ammonia as well as carbonate species than the hemolymph, indicating that unlike those of some euryhaline crabs the antennal glands of the Dungeness crab reabsorb these molecules rather than eliminate them for excretion.
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Braquiuros , ATPasas de Translocación de Protón Vacuolares , Animales , Amoníaco/metabolismo , Branquias/metabolismo , Transporte Biológico , Sodio/metabolismo , ATPasas de Translocación de Protón Vacuolares/metabolismo , Braquiuros/fisiología , ATPasa Intercambiadora de Sodio-Potasio/metabolismoRESUMEN
Total suspended solids (TSS) are a major contributor of anthropogenic impacts to aquatic systems. TSS exposure have been shown to affect the function of gills, but the mode of action is unclear. Zebrafish (Danio rerio) is emerging as an excellent model for mechanistic toxicology, and as there are no baseline studies on TSS effects in zebrafish gills, we tested the hypothesis that environmental concentrations of TSS damages gill structure and function in this species. Adult zebrafish were exposed to either 0, 10, 100, 500, 1000, or 2000 mg/L TSS for 4 days to assess the gill morphology. The minimal concentration that affected the gill structure was further tested for the distribution of key ion transporters, including Na+/K+- ATPase (NKA) and vacuolar-type H+-ATPase (VHA), using confocal microscopy. Our results reveal that TSS concentration as low as 100 mg/L alters the morphology of gills, including greater filament thickness, lamellae thickness, and epithelial lifting. This was also associated with a reduction in NKA immunoreactive (IR) cell count and intensity in the 100 mg/L TSS group, while there was neither a change in the VHA-IR cell count or expression nor the transcript abundance of atp6v1a and atp1a1a4 in the gills. Markers of stress response in these animals, including levels of cortisol, glucose, lactate, and glycogen were not altered after 4 days of TSS exposure. Overall, environmentally relevant concentrations of TSS can damage the gill structure and function in zebrafish and has the potential to enhance the toxicity of contaminants acting via the gills.
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Branquias , Contaminantes Químicos del Agua , Pez Cebra , Animales , Pez Cebra/fisiología , Branquias/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , ATPasa Intercambiadora de Sodio-Potasio/metabolismoRESUMEN
AIMS/HYPOTHESIS: The loss of pericytes surrounding the retinal vasculature in early diabetic retinopathy underlies changes to the neurovascular unit that lead to more destructive forms of the disease. However, it is unclear which changes lead to loss of retinal pericytes. This study investigated the hypothesis that chronic increases in one or more inflammatory factors mitigate the signalling pathways needed for pericyte survival. METHODS: Loss of pericytes and levels of inflammatory markers at the mRNA and protein levels were investigated in two genetic models of diabetes, Ins2Akita/+ (a model of type 1 diabetes) and Leprdb/db (a model of type 2 diabetes), at early stages of diabetic retinopathy. In addition, changes that accompany gliosis and the retinal vasculature were determined. Finally, changes in retinal pericytes chronically incubated with vehicle or increasing amounts of IFNγ were investigated to determine the effects on pericyte survival. The numbers of pericytes, microglia, astrocytes and endothelial cells in retinal flatmounts were determined by immunofluorescence. Protein and mRNA levels of inflammatory factors were determined using multiplex ELISAs and quantitative reverse transcription PCR (qRT-PCR). The effects of IFNγ on the murine retinal pericyte survival-related platelet-derived growth factor receptor ß (PDGFRß) signalling pathway were investigated by western blot analysis. Finally, the levels of cell death-associated protein kinase C isoform delta (PKCδ) and cleaved caspase 3 (CC3) in pericytes were determined by western blot analysis and immunocytochemistry. RESULTS: The essential findings of this study were that both type 1 and 2 diabetes were accompanied by a similar progression of retinal pericyte loss, as well as gliosis. However, inflammatory factor expression was dissimilar in the two models of diabetes, with peak expression occurring at different ages for each model. Retinal vascular changes were more severe in the type 2 diabetes model. Chronic incubation of murine retinal pericytes with IFNγ decreased PDGFRß signalling and increased the levels of active PKCδ and CC3. CONCLUSIONS/INTERPRETATION: We conclude that retinal inflammation is involved in and sustains pericyte loss as diabetic retinopathy progresses. Moreover, IFNγ plays a critical role in reducing pericyte survival in the retina by reducing activation of the PDGFRß signalling pathway and increasing PKCδ levels and pericyte apoptosis.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Ratones , Animales , Retinopatía Diabética/genética , Retinopatía Diabética/metabolismo , Modelos Animales de Enfermedad , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Células Endoteliales/metabolismo , Gliosis/complicaciones , Gliosis/metabolismo , Diabetes Mellitus Experimental/metabolismo , Retina/metabolismo , Inflamación/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Pericitos/metabolismoRESUMEN
INTRODUCTION: In the AWARD-7 study in patients with type 2 diabetes and moderate-to-severe chronic kidney disease, once-weekly dulaglutide slowed the decline in estimated glomerular filtration rate (eGFR) and decreased the urine albumin/creatinine ratio compared to insulin glargine at the end of 52 weeks of treatment. In this exploratory post hoc analysis, changes in two fibrosis biomarkers, serum PRO-C6 (type VI collagen formation) and urine C3M (type III collagen degradation), were evaluated. METHODS: In the groups treated with dulaglutide 1.5 mg or insulin glargine (N = 330), serum PRO-C6 and urine C3M were measured using competitive enzyme-linked immunosorbent assays. Biomarker changes were assessed by a mixed-effects model for repeated measures. Pearson correlation analyses were conducted to determine associations between changes in kidney fibrosis biomarkers and eGFR measures at 52 weeks. RESULTS: At weeks 26 and 52 of treatment in the overall population, serum PRO-C6 levels were significantly lower in the dulaglutide group versus insulin glargine group with percent change from baseline of (least squares mean ± standard error) -4.6% ± 1.9 and -0.2% ± 2.2 versus 5.7% ± 2.0 and 8.0% ± 2.3 (p < 0.01), respectively, and urine C3M levels were significantly higher in the dulaglutide group versus insulin glargine group with percent change from baseline of 10.9% ± 8.2 and 20.7% ± 8.8 versus -10.0% ± 6.5 and -16.9% ± 6.4 (p < 0.05), respectively. These findings appeared greater in the subgroup with macroalbuminuria. Serum PRO-C6 negatively correlated with eGFR, while urine C3M positively correlated with eGFR. CONCLUSION: Dulaglutide treatment was associated with biomarker changes that indicated lower type VI collagen formation and higher type III collagen degradation compared to treatment with insulin glargine, suggesting a potential drug effect to reduce kidney fibrosis.
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Diabetes Mellitus Tipo 2 , Insuficiencia Renal Crónica , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Insulina Glargina/uso terapéutico , Hipoglucemiantes/uso terapéutico , Colágeno Tipo VI , Colágeno Tipo III/uso terapéutico , Hemoglobina Glucada , Proteínas Recombinantes de Fusión/efectos adversos , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Biomarcadores , Riñón/metabolismoRESUMEN
Understanding local adaptation has become a key research area given the ongoing climate challenge and the concomitant requirement to conserve genetic resources. Perennial plants, such as forest trees, are good models to study local adaptation given their wide geographic distribution, largely outcrossing mating systems, and demographic histories. We evaluated signatures of local adaptation in European aspen (Populus tremula) across Europe by means of whole-genome resequencing of a collection of 411 individual trees. We dissected admixture patterns between aspen lineages and observed a strong genomic mosaicism in Scandinavian trees, evidencing different colonization trajectories into the peninsula from Russia, Central and Western Europe. As a consequence of the secondary contacts between populations after the last glacial maximum, we detected an adaptive introgression event in a genome region of â¼500 kb in chromosome 10, harboring a large-effect locus that has previously been shown to contribute to adaptation to the short growing seasons characteristic of Northern Scandinavia. Demographic simulations and ancestry inference suggest an Eastern origin-probably Russian-of the adaptive Nordic allele which nowadays is present in a homozygous state at the north of Scandinavia. The strength of introgression and positive selection signatures in this region is a unique feature in the genome. Furthermore, we detected signals of balancing selection, shared across regional populations, that highlight the importance of standing variation as a primary source of alleles that facilitate local adaptation. Our results, therefore, emphasize the importance of migration-selection balance underlying the genetic architecture of key adaptive quantitative traits.
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Adaptación Fisiológica , Populus , Adaptación Fisiológica/genética , Alelos , Europa (Continente) , Variación Genética , Genoma de Planta , Fenotipo , Populus/genética , Análisis de Secuencia de ADNRESUMEN
This study applies a large proteomics panel to search for new circulating biomarkers associated with progression to kidney failure in individuals with diabetic kidney disease. Four independent cohorts encompassing 754 individuals with type 1 and type 2 diabetes and early and late diabetic kidney disease were followed to ascertain progression to kidney failure. During ten years of follow-up, 227 of 754 individuals progressed to kidney failure. Using the SOMAscan proteomics platform, we measured baseline concentration of 1129 circulating proteins. In our previous publications, we analyzed 334 of these proteins that were members of specific candidate pathways involved in diabetic kidney disease and found 35 proteins strongly associated with risk of progression to kidney failure. Here, we examined the remaining 795 proteins using an untargeted approach. Of these remaining proteins, 11 were significantly associated with progression to kidney failure. Biological processes previously reported for these proteins were related to neuron development (DLL1, MATN2, NRX1B, KLK8, RTN4R and ROR1) and were implicated in the development of kidney fibrosis (LAYN, DLL1, MAPK11, MATN2, endostatin, and ROR1) in cellular and animal studies. Specific mechanisms that underlie involvement of these proteins in progression of diabetic kidney disease must be further investigated to assess their value as targets for kidney-protective therapies. Using multivariable LASSO regression analysis, five proteins (LAYN, ESAM, DLL1, MAPK11 and endostatin) were found independently associated with risk of progression to kidney failure. Thus, our study identified proteins that may be considered as new candidate prognostic biomarkers to predict risk of progression to kidney failure in diabetic kidney disease. Furthermore, three of these proteins (DLL1, ESAM, and MAPK11) were selected as candidate biomarkers when all SOMAscan results were evaluated.
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Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Insuficiencia Renal , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/etiología , Progresión de la Enfermedad , Endostatinas , Humanos , Lectinas Tipo C , Proteómica/métodosRESUMEN
Phenotypic divergence is a hallmark of adaptive radiation. One example involves differentiation in physiological traits involved in ion regulation among species with contrasting lifestyles and living in distinct environments. Differentiation in ion regulation and its ecological implications among populations within species are, however, less well understood. To address this knowledge gap, we collected prickly sculpin (Cottus asper) from distinct habitat types including coastal rivers connected to estuaries, coastal lakes and interior lakes, all from British Columbia, Canada. We tested for differences in plasma Na+ and Cl-, gill Na+/K+-ATPase and H+-ATPase activity and protein abundance as well as changes in body mass and arterial blood pH in fish sampled from the field and acclimated to two different freshwater conditions in the laboratory: artificial lake water (ALW) and ion-poor water (IPW). We also tested for links between environmental water chemistry and the physiological characteristics associated with ion regulation. Transfer to IPW resulted in upregulation of gill Na+/K+-ATPase and H+-ATPase activity as well as increases in gill H+-ATPase protein expression level in each habitat compared with that in the common ALW treatment. Despite the presence of population-within-habitat-type differences, significant habitat-type effects were revealed in most of the ion regulation characteristics examined under different acclimation conditions. Significantly lower plasma Cl- was detected in fish from coastal rivers than in fish from the other two habitat types during the IPW treatment, which was also significantly lower compared with that in ALW. Similarly, gill Na+/K+-ATPase activity was lower in the coastal river populations in IPW than in fish from coastal and interior lakes, which was not in accordance with the protein expression in the gill. For gill H+-ATPase, fish from interior lake populations had the highest level of activity across all habitat types under all conditions, which was related to the protein levels in the gill. The activity of gill H+-ATPase was positively correlated with the combined effect of water Na+ and pH under the ALW treatment. Our results suggest that variation in habitat may be an important factor driving differences in gill Na+/K+-ATPase and H+-ATPase activity across populations of C. asper. Further, the combined effect of water Na+ and pH may have played a key role in physiological adaptation in C. asper during post-glacial freshwater colonization and dispersal.
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Branquias , Perciformes , Aclimatación/fisiología , Adaptación Fisiológica , Animales , Peces/metabolismo , Agua Dulce , Branquias/metabolismo , Concentración de Iones de Hidrógeno , Iones/metabolismo , Perciformes/metabolismo , ATPasas de Translocación de Protón/metabolismo , Agua de Mar , Sodio/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Agua/metabolismoRESUMEN
In a phase 2 trial of once-weekly tirzepatide (1, 5, 10, or 15 mg), dulaglutide (1.5 mg), or placebo, the dual glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist tirzepatide dose-dependently reduced HbA1c and body weight in patients with type 2 diabetes. In this post hoc analysis, inflammation, endothelial dysfunction, and cellular stress biomarkers were measured at baseline, 4, 12, and 26 weeks to evaluate the additional effects of tirzepatide on cardiovascular risk factors. At 26 weeks, tirzepatide 10 and 15 mg decreased YKL-40 (also known as chitinase-3 like-protein-1), intercellular adhesion molecule 1 (ICAM-1), leptin, and growth differentiation factor 15 levels versus baseline, and YKL-40 and leptin levels versus placebo and dulaglutide. Tirzepatide 15 mg also decreased ICAM-1 levels versus placebo and dulaglutide, and high-sensitivity C-reactive protein (hsCRP) levels versus baseline and placebo, but not dulaglutide. GlycA, interleukin 6, vascular cell adhesion molecule 1, and N-terminal-pro hormone B-type natriuretic peptide levels were not significantly changed in any group. YKL-40, hsCRP, and ICAM-1 levels rapidly decreased within 4 weeks of treatment with tirzepatide 10 and 15 mg, whereas the decrease in leptin levels was more gradual and did not plateau by 26 weeks. In this hypothesis-generating exploratory analysis, tirzepatide decreased several biomarkers that have been associated with cardiovascular risk.
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Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Biomarcadores , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Polipéptido Inhibidor Gástrico/uso terapéutico , Receptor del Péptido 1 Similar al Glucagón/agonistas , Péptidos Similares al Glucagón/análogos & derivados , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Hipoglucemiantes/uso terapéutico , Fragmentos Fc de Inmunoglobulinas , Proteínas Recombinantes de Fusión , Factores de RiesgoRESUMEN
Invasive sea lampreys in the Laurentian Great Lakes are controlled by applying TFM (3-trifluoromethyl-4-nitrophenol) and niclosamide to streams infested with their larvae. Both agents uncouple oxidative phosphorylation in the mitochondria, but TFM specifically targets lampreys, which have a lower capacity to detoxify the lampricide. Niclosamide lacks specificity and is more potent than TFM. However, its greater potency is poorly understood. We tested the hypothesis that niclosamide is a stronger uncoupler of mitochondrial oxidative phosphorylation than TFM by measuring oxygen consumption rates in isolated liver mitochondria exposed to physiologically relevant concentrations of TFM, niclosamide, or their mixture (100 TFM:1 niclosamide) at environmentally relevant temperatures (7, 13, and 25 °C). Niclosamide increased State 4 respiration and decreased the respiratory control ratio (RCR) at much lower concentrations than TFM. Calculations of the relative EC50 values, the amount of TFM or niclosamide required to decrease the RCR by 50%, indicated that niclosamide was 40-60 times more potent than TFM. Warmer temperature did not appear to decrease the sensitivity of mitochondria to niclosamide or TFM, as observed in the intact sea lamprey exposed to TFM in warmer waters. We conclude that the extreme sensitivity of mitochondria to niclosamide contributes to its greater in vivo toxicity in the whole animal.
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Petromyzon , Animales , Sustancias Peligrosas , Lagos , Mitocondrias , Niclosamida/farmacología , RespiraciónRESUMEN
BACKGROUND: Enhanced recovery pathways are associated with improved postoperative outcomes. However, as enhanced recovery pathways have become more complex and varied, compliance has reduced. The 'DrEaMing' bundle re-prioritises early postoperative delivery of drinking, eating, and mobilising. We investigated relationships between DrEaMing compliance, postoperative hospital length of stay (LOS), and complications in a prospective multicentre major surgical cohort. METHODS: We interrogated the UK Perioperative Quality Improvement Programme dataset. Analyses were conducted in four stages. In an exploratory cohort, we identified independent predictors of DrEaMing. We quantified the association between delivery of DrEaMing (and its component variables) and prolonged LOS in a homogenous colorectal subgroup and assessed generalisability in multispecialty patients. Finally, LOS and complications were compared across hospitals, stratified by DrEaMing compliance. RESULTS: The exploratory cohort comprised 22 218 records, the colorectal subgroup 7230, and the multispecialty subgroup 5713. DrEaMing compliance was 59% (13 112 patients), 60% (4341 patients), and 60% (3421), respectively, but varied substantially between hospitals. Delivery of DrEaMing predicted reduced odds of prolonged LOS in colorectal (odds ratio 0.51 [0.43-0.59], P<0.001) and multispecialty cohorts (odds ratio 0.47 [0.41-0.53], P<0.001). At the hospital level, complications were not the primary determinant of LOS after colorectal surgery, but consistent delivery of DrEaMing was associated with significantly shorter LOS. CONCLUSIONS: Delivery of bundled and unbundled DrEaMing was associated with substantial reductions in postoperative LOS, independent of the effects of confounder variables. Consistency of process delivery, and not complications, predicted shorter hospital-level length of stay. DrEaMing may be adopted by perioperative health systems as a quality metric to support improved patient outcomes and reduced hospital length of stay.
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Neoplasias Colorrectales , Complicaciones Posoperatorias , Estudios de Cohortes , Neoplasias Colorrectales/cirugía , Humanos , Tiempo de Internación , Complicaciones Posoperatorias/epidemiología , Estudios ProspectivosRESUMEN
There has been little research on childhood lead exposure pathways since the 1990s. New data from Michigan in 2017-2021 for 429 children in 345 homes included lead in blood, paint, dust, soil, water, and other housing, demographic, and behavioral metrics. Fifty-three percent of these children had blood lead (BPb) ≥5 µg/dL. A repeated measures pathway model that accounted for multiple children in the same home was constructed using weighted least squares mean estimation and included variance-covariance model multiple imputation. Results showed that children's BPb was directly predicted by lead in settled floor house dust, child's age, season, and mouthing behavior and indirectly predicted by window sill and trough dust lead (DPb), bare soil lead (SPb), proportion of floors with carpets, and exterior building deteriorations. Paint lead (PPb) was also an indirect predictor of BPb through the soil and settled dust pathways. Water lead (WPb), water consumption and other lead sources/pathways were not significant predictors of BPb in this cohort. Although risk factors for individual children are highly variable and worthy of investigation to pinpoint their exposures, this study shows that the main direct and indirect pathways of lead exposure for most children in older housing remain paint and the contaminated dust and soil it generates. Pathway analyses in other jurisdictions using current data should be performed to confirm these results. This study suggests both DPb and BPb in high-risk homes may have declined since the 1990s and that lead in dust, soil, and paint all should be measured to predict risk and target remediation. Because most homes still have not been assessed for lead hazards and remediated, too many children remain at needless risk.
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Exposición a Riesgos Ambientales , Plomo , Anciano , Niño , Polvo/análisis , Exposición a Riesgos Ambientales/análisis , Humanos , Plomo/análisis , Michigan/epidemiología , Suelo , Agua/análisisRESUMEN
Stomach loss has occurred independently multiple times during gnathostome evolution with notable frequency within the Teleostei. Significantly, this loss of acid-peptic digestion has been found to correlate with the secondary genomic loss of the gastric proton pump subunits (atp4a, atp4b) and pepsinogens/pepsins (pga, pgc). Gastric glands produce gastric juice containing the acid and pepsin and thus their presence is a hallmark feature of a digestive system capable of acid-peptic digestion. However, in gobiid fishes although oesogaster and gastric glands have been identified histologically, their functional significance has been questioned. In the present study we address whether the gastric proton pump is present and expressed in gastric glands of the goby Neogobius species (Gobiidae) and in members of the family Oxudercidae, a group of amphibious gobiid fishes commonly known as mudskippers (genera: Periophthalmus, Boleophthalmus, Periophthalmodon and Scartelaos). We confirmed the presence of gastric glands and have immunohistochemically localized gastric proton pump expression to these glands in Neogobius fluviatilis and Periophthalmus novemradiatus, Periophthalmus barbarus and Boleophthalmus boddarti. Genome analysis in Neogobius melanostomus, Periophthalmus magnuspinnatus, Scartelaos histophorus, Boleophthalmus pectinirostris, and Periophthalmodon schlosseri revealed the presence of both atp4a and atp4b subunit orthologues in all species in a conserved genomic loci organization. Moreover, it was possible to deduce that the complete open reading frame and the key functional amino acid residues are present. The conserved expression of the gastric proton pump provides clear evidence of the potential for gastric acid secretion indicating that acid digestion is retained in these gobiid fishes and not lost.
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Perciformes , Bombas de Protones , Animales , Aminoácidos/metabolismo , Peces/genética , Peces/metabolismo , Pepsina A/metabolismo , Pepsinógenos/metabolismo , Perciformes/metabolismo , Bombas de Protones/genética , Bombas de Protones/metabolismo , EstómagoRESUMEN
BACKGROUND: Mechanisms underlying the pro gression of diabetic kidney disease to ESKD are not fully understood. METHODS: We performed global microRNA (miRNA) analysis on plasma from two cohorts consisting of 375 individuals with type 1 and type 2 diabetes with late diabetic kidney disease, and targeted proteomics analysis on plasma from four cohorts consisting of 746 individuals with late and early diabetic kidney disease. We examined structural lesions in kidney biopsy specimens from the 105 individuals with early diabetic kidney disease. Human umbilical vein endothelial cells were used to assess the effects of miRNA mimics or inhibitors on regulation of candidate proteins. RESULTS: In the late diabetic kidney disease cohorts, we identified 17 circulating miRNAs, represented by four exemplars (miR-1287-5p, miR-197-5p, miR-339-5p, and miR-328-3p), that were strongly associated with 10-year risk of ESKD. These miRNAs targeted proteins in the axon guidance pathway. Circulating levels of six of these proteins-most notably, EFNA4 and EPHA2-were strongly associated with 10-year risk of ESKD in all cohorts. Furthermore, circulating levels of these proteins correlated with severity of structural lesions in kidney biopsy specimens. In contrast, expression levels of genes encoding these proteins had no apparent effects on the lesions. In in vitro experiments, mimics of miR-1287-5p and miR-197-5p and inhibitors of miR-339-5p and miR-328-3p upregulated concentrations of EPHA2 in either cell lysate, supernatant, or both. CONCLUSIONS: This study reveals novel mechanisms involved in progression to ESKD and points to the importance of systemic factors in the development of diabetic kidney disease. Some circulating miRNAs and axon guidance pathway proteins represent potential targets for new therapies to prevent and treat this condition.
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Orientación del Axón/fisiología , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 2/sangre , Nefropatías Diabéticas/etiología , Fallo Renal Crónico/etiología , MicroARNs/sangre , Adulto , Estudios de Cohortes , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/sangre , Femenino , Humanos , Fallo Renal Crónico/sangre , Masculino , Persona de Mediana EdadRESUMEN
Introduction: The COVID-19 pandemic has prompted a shift in health care delivery and compelled a heavier reliance on telehealth. The objective of this study was to determine if differences in coverage policies by payer type resulted in differential telehealth use during the first 3 months of the COVID-19 pandemic. In this population-based cohort study of low-income Arkansans, Medicaid beneficiaries enrolled in the traditional Primary Care Case Management (PCCM) program were compared with Medicaid beneficiaries covered through premium assistance in private Qualified Health Plans (QHPs). Methods: A retrospective review was conducted of insurance claims records from June 1, 2019, to June 30, 2020, for synchronous telehealth and mobile health (m-health) visits, as well as other forms of telehealth. To establish the baseline equivalence of enrollees in the two groups, propensity score matching design was used on demographic and geographic characteristics, Charlson Comorbidity Index, broadband availability, and prior service utilization. Results: Compared with enrollees in the PCCM program, Medicaid expansion enrollees in QHPs had higher odds of having had at least one telehealth visit (adjusted odds ratio [aOR] = 1.35, 95% confidence interval [CI]: 1.29-1.42) during the early phase of the COVID-19 pandemic. Categorizing utilizations by domain, QHP enrollees were more likely to use synchronous telehealth (aOR = 1.31; 95% CI: 1.25-1.37) and m-health (aOR = 5.91; 95% CI: 4.25-8.21). A higher proportion of QHP enrollees also had at least one mental or behavioral health telehealth session (aOR = 1.13; 95% CI: 1.07-1.19). Conclusions: Our study demonstrated that within low-income populations, payer type was associated with inequitable access to telehealth during the early phase of the COVID-19 pandemic.