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1.
eNeuro ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621991

RESUMO

The medial mammillary bodies (MB) play an important role in the formation of spatial memories; their dense inputs from hippocampal and brainstem regions makes them well-placed to integrate movement-related and spatial information, that is then extended to the anterior thalamic nuclei and beyond to cortex. While the anatomical connectivity of the medial MBs has been well-studied, much less is known about their physiological properties, particularly in freely-moving animals. We therefore carried out a comprehensive characterization of medial MB electrophysiology across arousal states by concurrently recording from the medial MB and the CA1 field of the hippocampus in male rats. In agreement with previous studies, we found medial MB neurons to have firing rates modulated by running speed and angular head velocity, as well as theta-entrained firing. We extended the characterization of MB neuron electrophysiology in three key ways: 1) we identified a subset of neurons (25%) that exhibit dominant bursting activity; 2) we showed that ∼30% of theta-entrained neurons exhibit robust theta cycle skipping, a firing characteristic that implicates them in a network for prospective coding of position; 3) a considerable proportion of medial MB units showed sharp wave-ripple (SWR) responsive firing (∼37%). The functional heterogeneity of MB electrophysiology reinforces their role as an integrative node for mnemonic processing and identifies potential roles for the MBs in memory consolidation through propagation of SWR-responsive activity to the anterior thalamus and prospective coding in the form of theta-cycle skipping.Significance Statement While the medial mammillary bodies (MBs) are important for memory, it is still not clear how they support memory formation. Through conjoint medial MB and hippocampal recordings across different arousal states we identified a population of medial MB units with diverse and often conjunctive physiological properties, including theta-entrained cells, cells modulated by running speed and angular head velocity, complex bursting, theta cycle skipping activity, and hippocampal sharp-wave ripple-responsive firing. These properties likely support a role for the medial MBs in mnemonic processing, enabling the integration of separate sensory streams and the propagation of information to the thalamus.

2.
Am J Kidney Dis ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38493378

RESUMO

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.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38438092

RESUMO

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.


Assuntos
Braquiúros , ATPases Vacuolares Próton-Translocadoras , Animais , Amônia/metabolismo , Brânquias/metabolismo , Transporte Biológico , Sódio/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Braquiúros/fisiologia , ATPase Trocadora de Sódio-Potássio/metabolismo
4.
New Phytol ; 242(2): 392-423, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38409806

RESUMO

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.


Assuntos
Ecossistema , Fósseis , Ecologia , Plantas , Fenótipo
5.
Acta Physiol (Oxf) ; 240(2): e14078, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38205922

RESUMO

AIM: To determine whether the crustacean Rh1 protein functions as a dual CO2 /ammonia transporter and investigate its role in branchial ammonia excretion and acid-base regulation. METHODS: Sequence analysis of decapod Rh1 proteins was used to determine the conservation of amino acid residues putatively involved in ammonia transport and CO2 binding in human and bacterial Rh proteins. Using the Carcinus maenas Rh1 protein (CmRh1) as a representative of decapod Rh1 proteins, we test the ammonia and CO2 transport capabilities of CmRh1 through heterologous expression in yeast and Xenopus oocytes coupled with site-directed mutagenesis. Quantitative PCR was used to assess the distribution of CmRh1 mRNA in various tissues. Western blotting was used to assess CmRh1 protein expression changes in response to high environmental ammonia and CO2 . Further, immunohistochemistry was used to assess sub-cellular localization of CmRh1 and a membrane-bound carbonic anhydrase (CmCAg). RESULTS: Sequence analysis of decapod Rh proteins revealed high conservation of several amino acid residues putatively involved in conducting ammonia transport and CO2 binding. Expression of CmRh1 in Xenopus oocytes enhanced both ammonia and CO2 transport which was nullified in CmRh1 D180N mutant oocytes. Transport of the ammonia analog methylamine by CmRh1 is dependent on both ionized and un-ionized ammonia/methylamine species. CmRh1 was co-localized with CmCAg to the apical membrane of the crustacean gill and only experienced decreased protein expression in the anterior gills when exposed to high environmental ammonia. CONCLUSION: CmRh1 is the first identified apical transporter-mediated route for ammonia and CO2 excretion in the crustacean gill. Our findings shed further light on the potential universality of dual ammonia and CO2 transport capacity of Rhesus glycoproteins in both vertebrates and invertebrates.


Assuntos
Amônia , Dióxido de Carbono , Animais , Humanos , Dióxido de Carbono/metabolismo , Amônia/metabolismo , Glicoproteínas/química , Glicoproteínas/genética , Glicoproteínas/metabolismo , Aminoácidos , Metilaminas
6.
Am J Kidney Dis ; 83(1): 58-70, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37690631

RESUMO

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.


Assuntos
Doenças Cardiovasculares , Hiperparatireoidismo Secundário , Adulto , Humanos , Cinacalcete/uso terapêutico , Naftalenos/uso terapêutico , Resultado do Tratamento , Hiperparatireoidismo Secundário/tratamento farmacológico , Hiperparatireoidismo Secundário/etiologia , Vitamina D/uso terapêutico , Diálise Renal/efeitos adversos , Vitaminas/uso terapêutico , Hormônio Paratireóideo , Esteróis/uso terapêutico , Doenças Cardiovasculares/etiologia
7.
Genome Biol Evol ; 16(1)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38109935

RESUMO

Human activities are accelerating rates of biological invasions and climate-driven range expansions globally, yet we understand little of how genomic processes facilitate the invasion process. Although most of the literature has focused on underlying phenotypic correlates of invasiveness, advances in genomic technologies are showing a strong link between genomic variation and invasion success. Here, we consider the ability of genomic tools and technologies to (i) inform mechanistic understanding of biological invasions and (ii) solve real-world issues in predicting and managing biological invasions. For both, we examine the current state of the field and discuss how genomics can be leveraged in the future. In addition, we make recommendations pertinent to broader research issues, such as data sovereignty, metadata standards, collaboration, and science communication best practices that will require concerted efforts from the global invasion genomics community.


Assuntos
Genômica , Espécies Introduzidas , Humanos , Clima
8.
Curr Biol ; 33(20): R1044-R1046, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37875076

RESUMO

The eccentric seahorses, seadragons, pipehorses and pipefishes (Syngnathidae) have an aglomerular kidney1. Here, we show that nephron genes2 conserved in Bilateria are secondarily eroded/deleted in Syngnathidae genomes. A transcriptome enrichment analysis suggests the predominance of excretion processes in the Syngnathidae kidney. In a lineage where crypsis and idleness are tightly associated, we propose that aglomerulism evolved as an energy-saving strategy.


Assuntos
Smegmamorpha , Animais , Smegmamorpha/genética , Rim
9.
J Spec Oper Med ; 23(3): 91-100, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37733954

RESUMO

The potential for delayed evacuation of injured Service members from austere environments highlights the need to develop solutions that can stabilize a wound and enable mobility during these prolonged casualty care (PCC) scenarios. Lower extremity fractures have traditionally been treated by immobilization (splinting) followed by air evacuation - a paradigm not practical in PCC scenarios. In the civilian sector, treatment of extremity injuries sustained during remote recreational activities have similar challenges, particularly when adverse weather or terrain precludes early ground or air rescue. This review examines currently available fracture treatment solutions to include splinting, orthotic devices, and biological interventions and evaluates their feasibility: 1) for prolonged use in austere environments and 2) to enable patient mobilization. This review returned three common types of splints to include: a simple box splint, pneumatic splints, and traction splints. None of these splinting techniques allowed for ambulation. However, fixed facility-based orthotic interventions that include weight-bearing features may be combined with common splinting techniques to improve mobility. Biologically-focused technologies to stabilize a long bone fracture are still in their infancy. Integrating design features across these technologies could generate advanced treatments which would enable mobility, thus maximizing survivability until patient evacuation is feasible.

10.
Diabetologia ; 66(11): 2170-2185, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37670018

RESUMO

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.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Camundongos , Animais , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Modelos Animais de Doenças , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Células Endoteliais/metabolismo , Gliose/complicações , Gliose/metabolismo , Diabetes Mellitus Experimental/metabolismo , Retina/metabolismo , Inflamação/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Pericitos/metabolismo
11.
Diabetes Care ; 46(8): 1501-1506, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37267479

RESUMO

OBJECTIVE: Tirzepatide reduces HbA1c and body weight, and creatinine-based estimated glomerular filtration rate (eGFR) decline. Unlike creatine-derived eGFR (eGFR-creatinine), cystatin C-derived eGFR (eGFR-cystatin C) is unaffected by muscle mass changes. We assessed effects of tirzepatide on eGFR-creatinine and eGFR-cystatin C. RESEARCH DESIGN AND METHODS: Our primary outcome was eGFR change from baseline at 52 weeks with pooled tirzepatide (5, 10, and 15 mg) and titrated insulin glargine in adults with type 2 diabetes and high cardiovascular risk (SURPASS-4). RESULTS: Least squares mean (SE) eGFR-creatinine (mL/min/1.73 m2) changes from baseline with tirzepatide and insulin glargine were -2.5 (0.38) and -3.9 (0.38) (between-group difference, 1.4 [95% CI 0.3-2.4]) and -3.5 (0.37) and -5.3 (0.37) (between-group difference, 1.8 [95% CI 0.8-2.8]) for eGFR-cystatin C. Baseline, 1-year, and 1-year change from baseline values significantly correlated between eGFR-cystatin C and eGFR-creatinine. Measures of eGFR changes did not correlate with body weight changes. CONCLUSIONS: Tirzepatide slows the eGFR decline rate, supporting a kidney-protective effect.


Assuntos
Diabetes Mellitus Tipo 2 , Adulto , Humanos , Insulina Glargina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Cistatina C/farmacologia , Creatinina , Taxa de Filtração Glomerular/fisiologia , Rim , Peso Corporal
12.
J Neurosurg ; 139(6): 1748-1756, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37148230

RESUMO

OBJECTIVE: The study objective was to create a novel milestones evaluation form for neurosurgery sub-interns and assess its potential as a quantitative and standardized performance assessment to compare potential residency applicants. In this pilot study, the authors aimed to determine the form's interrater reliability, relationship to percentile assignments in the neurosurgery standardized letter of recommendation (SLOR), ability to quantitatively differentiate tiers of students, and ease of use. METHODS: Medical student milestones were either adapted from the resident Neurological Surgery Milestones or created de novo to evaluate a student's medical knowledge, procedural aptitude, professionalism, interpersonal and communication skills, and evidence-based practice and improvement. Four milestone levels were defined, corresponding to estimated 3rd-year medical student through 2nd-year resident levels. Faculty and resident evaluations as well as student self-evaluations were completed for 35 sub-interns across 8 programs. A cumulative milestone score (CMS) was computed for each student. Student CMSs were compared both within and between programs. Interrater reliability was determined with Kendall's coefficient of concordance (Kendall's W). Student CMSs were compared against their percentile assignments in the SLOR using analysis of variance with post hoc testing. CMS-derived percentile rankings were assigned to quantitatively distinguish tiers of students. Students and faculty were surveyed on the form's usefulness. RESULTS: The average faculty rating overall was 3.20, similar to the estimated competency level of an intern. Student and faculty ratings were similar, whereas resident ratings were lower (p < 0.001). Students were rated most highly in coachability and feedback (3.49 and 3.67, respectively) and lowest in bedside procedural aptitude (2.90 and 2.85, respectively) in both faculty and self-evaluations. The median CMS was 26.5 (IQR 21.75-29.75, range 14-32) with only 2 students (5.7%) achieving the highest rating of 32. Programs that evaluated the most students differentiated the highest-performing students from the lowest by at least 13 points. A program with 3 faculty raters demonstrated scoring agreement across 5 students (p = 0.024). The CMS differed significantly between SLOR percentile assignments, despite 25% of students being assigned to the top fifth percentile. CMS-driven percentile assignment significantly differentiated the bottom, middle, and top third of students (p < 0.001). Faculty and students strongly endorsed the milestones form. CONCLUSIONS: The medical student milestones form was well received and differentiated neurosurgery sub-interns both within and across programs. This form has potential as a replacement for numerical Step 1 scoring as a standardized, quantitative performance assessment for neurosurgery residency applicants.


Assuntos
Internato e Residência , Neurocirurgia , Humanos , Neurocirurgia/educação , Projetos Piloto , Reprodutibilidade dos Testes , Competência Clínica , Avaliação Educacional
13.
Nat Commun ; 14(1): 1717, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36973251

RESUMO

Adaptation is the central feature and leading explanation for the evolutionary diversification of life. Adaptation is also notoriously difficult to study in nature, owing to its complexity and logistically prohibitive timescale. Here, we leverage extensive contemporary and historical collections of Ambrosia artemisiifolia-an aggressively invasive weed and primary cause of pollen-induced hayfever-to track the phenotypic and genetic causes of recent local adaptation across its native and invasive ranges in North America and Europe, respectively. Large haploblocks-indicative of chromosomal inversions-contain a disproportionate share (26%) of genomic regions conferring parallel adaptation to local climates between ranges, are associated with rapidly adapting traits, and exhibit dramatic frequency shifts over space and time. These results highlight the importance of large-effect standing variants in rapid adaptation, which have been critical to A. artemisiifolia's global spread across vast climatic gradients.


Assuntos
Ambrosia , Plantas Daninhas , Ambrosia/genética , Plantas Daninhas/genética , Aclimatação , Adaptação Fisiológica/genética , Evolução Biológica
14.
Diabetes Care ; 46(5): 1046-1051, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36897834

RESUMO

OBJECTIVE: The glucagon-like peptide-1 receptor agonist dulaglutide reduced MACE in the Researching Cardiovascular Events with a Weekly Incretin in Diabetes (REWIND) trial. This article expores the relationship of selected biomarkers to both dulaglutide and major adverse cardiovascular events (MACE). RESEARCH DESIGN AND METHODS: In this post hoc analysis, stored fasting baseline and 2-year plasma samples from 824 REWIND participants with MACE during follow-up and 845 matched non-MACE participants were analyzed for 2-year changes in 19 protein biomarkers. Two-year changes in 135 metabolites were also analyzed in 600 participants with MACE during follow-up and in 601 matched non-MACE participants. Linear and logistic regression models were used to identify proteins that were associated with both dulaglutide treatment and MACE. Similar models were used to identify metabolites that were associated with both dulaglutide treatment and MACE. RESULTS: Compared with placebo, dulaglutide was associated with a greater reduction or lesser 2-year rise from baseline in N-terminal prohormone of brain natriuretic peptide (NT-proBNP), growth differentiation factor 15 (GDF-15), high-sensitivity C-reactive protein, and a greater 2-year rise in C-peptide. Compared with placebo, dulaglutide was also associated with a greater fall from baseline in 2-hydroxybutyric acid and a greater rise in threonine (P < 0.001). Increases from baseline in two of the proteins (but neither metabolite) were associated with MACE, including NT-proBNP (OR 1.267; 95% CI 1.119, 1.435; P < 0.001) and GDF-15 (OR 1.937; 95% CI 1.424, 2.634; P < 0.001). CONCLUSIONS: Dulaglutide was associated with a reduced 2-year rise from baseline of NT-proBNP and GDF-15. Higher rises of these biomarkers were also associated with MACE.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Humanos , Hipoglicemiantes/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Fator 15 de Diferenciação de Crescimento/uso terapêutico , Método Duplo-Cego , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Proteínas Recombinantes de Fusão/efeitos adversos , Doenças Cardiovasculares/complicações , Biomarcadores , Estudos de Casos e Controles
15.
Am J Nephrol ; 54(1-2): 74-82, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36754023

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Renal Crônica , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Insulina Glargina/uso terapêutico , Hipoglicemiantes/uso terapêutico , Colágeno Tipo VI , Colágeno Tipo III/uso terapêutico , Hemoglobinas Glicadas , Proteínas Recombinantes de Fusão/efeitos adversos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Biomarcadores , Rim/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-36834236

RESUMO

Experiences of adversity can generate positive psychological effects alongside negative impacts. Little research to date has evaluated predictors of post-traumatic growth in mental or community healthcare workers during the COVID-19 pandemic. Following a survey of 854 community and mental healthcare staff in the United Kingdom in July to September 2020, multiple linear regression was used to determine the association between hypothesised risk and protective factors (personal, organisational and environmental variables) and total scores on the Post-traumatic Growth Inventory-Short Version. Positive self-reflection activities, black and minority ethnic status, developing new healthcare knowledge and skills, connecting with friends and family, feeling supported by senior management, feeling supported by the UK people, and anxiety about the personal and work-related consequences of COVID-19 each significantly independently predicted greater post-traumatic growth. Working in a clinical role and in mental healthcare or community physical healthcare predicted lower post-traumatic growth. Our research supports the value of taking an organisational growth-focused approach to occupational health during times of adversity, by supporting staff to embrace opportunities for personal growth. Valuing staff's cultural and religious identity and encouraging self-reflective activities, such as mindfulness and meditation, may help to promote post-traumatic growth.


Assuntos
COVID-19 , Crescimento Psicológico Pós-Traumático , Humanos , Pandemias , Pessoal de Saúde/psicologia , Ansiedade , Reino Unido
18.
Science ; 378(6620): 642-646, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36356120

RESUMO

The earliest vascular plants had stems with a central cylindrical strand of water-conducting xylem, which rapidly diversified into more complex shapes. This diversification is understood to coincide with increases in plant body size and branching; however, no selection pressure favoring xylem strand-shape complexity is known. We show that incremental changes in xylem network organization that diverge from the cylindrical ancestral form lead to progressively greater drought resistance by reducing the risk of hydraulic failure. As xylem strand complexity increases, independent pathways for embolism spread become fewer and increasingly concentrated in more centrally located conduits, thus limiting the systemic spread of embolism during drought. Selection by drought may thus explain observed trajectories of xylem strand evolution in the fossil record and the diversity of extant forms.


Assuntos
Evolução Biológica , Secas , Traqueófitas , Água , Xilema , Folhas de Planta/metabolismo , Traqueófitas/metabolismo , Água/metabolismo , Xilema/metabolismo
19.
Front Physiol ; 13: 966447, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36237533

RESUMO

An acid-secreting stomach provides many selective advantages to fish and other vertebrates; however, phenotypic stomach loss has occurred independently multiple times and is linked to loss of expression of both the gastric proton pump and the protease pepsin. Reasons underpinning stomach loss remain uncertain. Understanding the importance of gastric acid-secretion to the metabolic costs of digestion and growth will provide information about the metabolic expense of acid-production and performance. In this study, omeprazole, a well characterized gastric proton pump inhibitor, was used to simulate the agastric phenotype by significantly inhibiting gastric acidification in Nile tilapia. The effects on post-prandial metabolic rate and growth were assessed using intermittent flow respirometry and growth trials, respectively. Omeprazole reduced the duration (34.4%) and magnitude (34.5%) of the specific dynamic action and specific growth rate (21.3%) suggesting a decrease in digestion and assimilation of the meal. Gastric pH was measured in control and omeprazole treated fish to confirm that gastric acid secretion was inhibited for up to 12 h post-treatment (p < 0.05). Gastric evacuation measurements confirm a more rapid emptying of the stomach in omeprazole treated fish. These findings reinforce the importance of stomach acidification in digestion and growth and present a novel way of determining costs of gastric digestion.

20.
Physiol Biochem Zool ; 95(6): 551-567, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36283107

RESUMO

Little is known about nitrogenous waste (N waste) handling and excretion (JN waste) during the complex life cycle of the sea lamprey (Petromyzon marinus), an extant jawless fish that undergoes a complete metamorphosis from a filter-feeding larva (ammocoete) into a parasitic juvenile that feeds on the blood of larger, jawed fishes. Here, we investigate the ammonia- and urea-handling profiles of sea lampreys before, during, and after metamorphosis. The rates of ammonia excretion (Jamm) and urea excretion (Jurea) significantly decreased after the onset of metamorphosis, with the lowest rates observed during midmetamorphosis. Near the completion of metamorphosis, rates of JN waste (JN waste=Jamm+Jurea) significantly increased as sea lampreys entered the juvenile period. Feeding juvenile lampreys had greater than 10- to 15-fold higher Jamm and fivefold higher Jurea compared to nonfed juveniles, which corresponded to higher postprandial (postfeeding) concentrations of plasma ammonia and urea. The routes of Jamm and Jurea completely diverged following metamorphosis. In larvae, Jamm was equally split between branchial (gills) and extrabranchial (skin plus renal) pathways, but following metamorphosis, >80% of ammonia was excreted via the gills in nonfeeding juvenile lampreys, and >95% of ammonia was excreted via the gills in adult sea lampreys. Urea, on the other hand, was predominantly excreted via extrabranchial routes and, to a lesser extent, the gills in larvae and in nonfeeding juveniles. In adults, however, virtually all urea was excreted via urine. Reverse transcription polymerase chain reaction and in silico analyses also indicated that a urea transporter encoded by a slc4a2-like gene is present in lampreys. The branchial expression of this transporter is modulated throughout sea lamprey life history, as it is higher in the larvae and steadily decreases until the adult stage. We conclude that the divergent pathways of Jamm and Jurea during the sea lamprey life cycle reflect changes in their habitat, lifestyle, and diet. Further, the near-complete reliance on renal routes for Jurea in adult sea lampreys is unique among fishes and may reflect the ancestral condition of how this N waste product was handled and excreted by the earliest vertebrates.


Assuntos
Petromyzon , Animais , Petromyzon/metabolismo , Amônia/metabolismo , Ureia/metabolismo , Estágios do Ciclo de Vida , Lampreias , Metamorfose Biológica , Peixes/metabolismo , Larva/metabolismo , Nitrogênio/metabolismo , Resíduos
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