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1.
Nat Genet ; 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38862854

ABSTRACT

Coronary artery disease (CAD) exists on a spectrum of disease represented by a combination of risk factors and pathogenic processes. An in silico score for CAD built using machine learning and clinical data in electronic health records captures disease progression, severity and underdiagnosis on this spectrum and could enhance genetic discovery efforts for CAD. Here we tested associations of rare and ultrarare coding variants with the in silico score for CAD in the UK Biobank, All of Us Research Program and BioMe Biobank. We identified associations in 17 genes; of these, 14 show at least moderate levels of prior genetic, biological and/or clinical support for CAD. We also observed an excess of ultrarare coding variants in 321 aggregated CAD genes, suggesting more ultrarare variant associations await discovery. These results expand our understanding of the genetic etiology of CAD and illustrate how digital markers can enhance genetic association investigations for complex diseases.

2.
Health Informatics J ; 30(2): 14604582241259337, 2024.
Article in English | MEDLINE | ID: mdl-38838647

ABSTRACT

Objective: To evaluate the impact of PDMP integration in the EHR on provider query rates within twelve primary care clinics in one academic medical center. Methods: Using linked data from the EHR and state PDMP program, we evaluated changes in PDMP query rates using a stepped-wedge observational design where integration was implemented in three waves (four clinics per wave) over a five-month period (May, July, September 2019). Multivariable negative binomial general estimating equations (GEE) models assessed changes in PDMP query rates, overall and across several provider and clinic-level subgroups. Results: Among 206 providers in PDMP integrated clinics, the average number of queries per provider per month increased significantly from 1.43 (95% CI 1.07 - 1.91) pre-integration to 3.94 (95% CI 2.96 - 5.24) post-integration, a 2.74-fold increase (95% CI 2.11 to 3.59; p < .0001). Those in the lowest quartile of PDMP use pre-integration increased 36.8-fold (95% CI 16.91 - 79.95) after integration, significantly more than other pre-integration PDMP use quartiles. Conclusions: Integration of the PDMP in the EHR significantly increased the use of the PDMP overall and across all studied subgroups. PDMP use increased to a greater degree among providers with lower PDMP use pre-integration.


Subject(s)
Electronic Health Records , Prescription Drug Monitoring Programs , Primary Health Care , Humans , Electronic Health Records/statistics & numerical data , Primary Health Care/statistics & numerical data , Prescription Drug Monitoring Programs/statistics & numerical data , Prescription Drug Monitoring Programs/trends , Health Personnel/statistics & numerical data , Health Personnel/psychology , Female , Male
3.
Biomed Opt Express ; 15(5): 3426-3440, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38855699

ABSTRACT

The sclera plays an important role in the structural integrity of the eye. However, as myopia progresses, the elongation of the eyeball exerts stretching forces on the posterior sclera, which typically happens in conjunction with scleral remodeling that causes rigidity loss. These biomechanical alterations can cause localized eyeball deformation and vision impairment. Therefore, monitoring scleral rigidity is clinically important for the management and risk assessment of myopia. In this study, we propose fundus pulsation optical coherence elastography (FP-OCE) to characterize posterior scleral rigidity in living humans. This methodology is based on a choroidal pulsation model, where the scleral rigidity is inversely associated with the choroidal max strain obtained through phase-sensitive optical coherence tomography (PhS-OCT) measurement of choroidal deformation and thickness. Using FP-OCE, we conducted a pilot clinical study to explore the relationship between choroidal strain and myopia severity. The results revealed a significant increase in choroidal max strain in pathologic myopia, indicating a critical threshold beyond which scleral rigidity decreases significantly. Our findings offer a potential new method for monitoring myopia progression and evaluating therapies that alter scleral mechanical properties.

4.
JCO Precis Oncol ; 8: e2300362, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38865671

ABSTRACT

PURPOSE: There is significant interest in identifying complete responders to neoadjuvant chemotherapy (NAC) before radical cystectomy (RC) to potentially avoid removal of a pathologically benign bladder. However, clinical restaging after NAC is highly inaccurate. The objective of this study was to develop a next-generation sequencing-based molecular assay using urine to enhance clinical staging of patients with bladder cancer. METHODS: Urine samples from 20 and 44 patients with bladder cancer undergoing RC were prospectively collected for retrospective analysis for molecular correlate analysis from two clinical trials, respectively. The first cohort was used to benchmark the assay, and the second was used to determine the performance characteristics of the test as it correlates to responder status as measured by pathologic examination. RESULTS: First, to benchmark the assay, known mutations identified in the tissue (MT) of patients from the Accelerated Methotrexate, Vinblastine, Doxorubicin, Cisplatin trial (ClinicalTrials.gov identifier: NCT01611662, n = 16) and a cohort from University of California-San Francisco (n = 4) were cross referenced against mutation profiles from urine (MU). We then determined the correlation between MU persistence and residual disease in pre-RC urine samples from a second prospective clinical trial (The pT0 trial; ClinicalTrials.gov identifier: NCT02968732). Residual MU status correlated strongly with residual disease status (pT0 trial; n = 44; P = .0092) when MU from urine supernatant and urine pellet were assessed separately and analyzed in tandem. The sensitivity, specificity, PPV, and NPV were 91%, 50%, 86%, and 63% respectively, with an overall accuracy of 82% for this second cohort. CONCLUSION: MU are representative of MT and thus can be used to enhance clinical staging of urothelial carcinoma. Urine biopsy may be used as a reliable tool that can be further developed to identify complete response to NAC in anticipation of safe RC avoidance.


Subject(s)
Biomarkers, Tumor , Cystectomy , Neoplasm Staging , Urinary Bladder Neoplasms , Humans , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/urine , Urinary Bladder Neoplasms/surgery , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/genetics , Female , Male , Middle Aged , Aged , Biomarkers, Tumor/urine , Biopsy , Retrospective Studies , Neoadjuvant Therapy
5.
Otol Neurotol ; 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38896787

ABSTRACT

AIM: To characterize vestibular recovery in a mouse model of unilateral labyrinthotomy under local AAT and dexamethasone treatment. BACKGROUND: Alpha1-antitrypsin (AAT) is a circulating tissue-protective molecule that rises during inflammatory conditions and promotes inflammatory resolution. Its local concentration in human perilymph inversely correlates with the severity of inner ear dysfunction; concomitantly, mice that overexpress AAT and undergo inner ear trauma rapidly restore vestibular function. Locally applied AAT has yet to be examined in this context, nor has it been directly compared with anti-inflammatory corticosteroid treatment. METHODS: Wild-type mice C57BL/6 underwent a unilateral inner ear injury. Nine microliters of saline, clinical-grade AAT (180 µg/site), dexamethasone (4 mg/site), or both were applied locally on Days 0, 1, and 2 (n = 5/group). Vestibular function was assessed for 7 days. An in vitro human epithelial gap closure assay was performed using A549 cells in the presence of AAT and/or dexamethasone. RESULTS: Upon labyrinthotomy, all groups displayed severe vestibular dysfunction. Saline-treated mice showed the longest impairment. That group and the dexamethasone group displayed partial to no recovery, while AAT-treated mice exhibited complete recovery within 7 days; at this time point, dexamethasone-treated mice exhibited 50% recovery. Objective vestibular testing showed similar outcomes. In vitro, cotreatment with AAT and dexamethasone resulted in a gap closure dynamic that was superior to AAT alone at 6 h and superior to DEX alone at 48 h. CONCLUSION: Locally applied AAT treatment is superior to locally applied dexamethasone in promoting vestibular recovery in vivo. Ongoing studies are exploring the potential advantages of AAT combined with early low-dose dexamethasone therapy.

6.
Infect Immun ; : e0026323, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38899881

ABSTRACT

Because most humans resist Mycobacterium tuberculosis infection, there is a paucity of lung samples to study. To address this gap, we infected Diversity Outbred mice with M. tuberculosis and studied the lungs of mice in different disease states. After a low-dose aerosol infection, progressors succumbed to acute, inflammatory lung disease within 60 days, while controllers maintained asymptomatic infection for at least 60 days, and then developed chronic pulmonary tuberculosis (TB) lasting months to more than 1 year. Here, we identified features of asymptomatic M. tuberculosis infection by applying computational and statistical approaches to multimodal data sets. Cytokines and anti-M. tuberculosis cell wall antibodies discriminated progressors vs controllers with chronic pulmonary TB but could not classify mice with asymptomatic infection. However, a novel deep-learning neural network trained on lung granuloma images was able to accurately classify asymptomatically infected lungs vs acute pulmonary TB in progressors vs chronic pulmonary TB in controllers, and discrimination was based on perivascular and peribronchiolar lymphocytes. Because the discriminatory lesion was rich in lymphocytes and CD4 T cell-mediated immunity is required for resistance, we expected CD4 T-cell genes would be elevated in asymptomatic infection. However, the significantly different, highly expressed genes were from B-cell pathways (e.g., Bank1, Cd19, Cd79, Fcmr, Ms4a1, Pax5, and H2-Ob), and CD20+ B cells were enriched in the perivascular and peribronchiolar regions of mice with asymptomatic M. tuberculosis infection. Together, these results indicate that genetically controlled B-cell responses are important for establishing asymptomatic M. tuberculosis lung infection.

7.
Radiol Case Rep ; 19(8): 3470-3472, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38872751

ABSTRACT

Female gymnasts are the athletes that are most likely to experience Achilles tendon rupture, due to the high energy and eccentric load place on their Achilles tendon related to their sport. It is postulated that degenerative changes, watershed vascular supply, calcifications, and high amounts of inflammatory cells may play a role. This case report highlights an athlete with an asymptomatic Achilles tendon that was visualized to be normal utilizing ultrasound. She was found to have no evidence of underlying tendon pathology. The athlete then ruptured her Achilles tendon 8 months later during a gymnastic meet with no proceeding symptoms. This case report challenges the accepted theory that preexisting tendinosis or pathology proceeds Achilles tendon rupture. In this case, it is postulated that tendon rupture may be secondary to significant mechanical force even without underlying pathology. Level of evidence: Level 4.

8.
Neurooncol Adv ; 6(1): vdae058, 2024.
Article in English | MEDLINE | ID: mdl-38887507

ABSTRACT

Background: The progression of vestibular schwannoma (VS) is intricately linked with interactions between schwannoma cells and the extracellular matrix. Surgical resection of VS is associated with substantial risks as tumors are adherent to the brainstem and cranial nerves. We evaluate the role of matrix metalloproteinase 9 (MMP9) in VS and explore its potential as a biomarker to classify adherent VS. Methods: Transcriptomic analysis of a murine schwannoma allograft model and immunohistochemical analysis of 17 human VS were performed. MMP9 abundance was assessed in mouse and human schwannoma cell lines. Transwell studies were performed to evaluate the effect of MMP9 on schwannoma invasion in vitro. Plasma biomarkers were identified from a multiplexed proteomic analysis in 45 prospective VS patients and validated in primary culture. The therapeutic efficacy of MMP9 inhibition was evaluated in a mouse schwannoma model. Results: MMP9 was the most highly upregulated protease in mouse schwannomas and was significantly enriched in adherent VS, particularly around tumor vasculature. High levels of MMP9 were found in plasma of patients with adherent VS. MMP9 outperformed clinical and radiographic variables to classify adherent VS with outstanding discriminatory ability. Human schwannoma cells secreted MMP9 in response to TNF-α which promoted cellular invasion and adhesion protein expression in vitro. Lastly, MMP9 inhibition decreased mouse schwannoma growth in vivo. Conclusions: We identify MMP9 as a preoperative biomarker to classify adherent VS. MMP9 may represent a new therapeutic target in adherent VS associated with poor surgical outcomes that lack other viable treatment options.

9.
Ann Emerg Med ; 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38888534

ABSTRACT

STUDY OBJECTIVE: Emergency department (ED) screening for child physical abuse has been widely implemented, with uncertain effects on child abuse identification. Our goal was to determine the effect of screening on referrals to child protective services (CPS) identifying abuse. METHODS: We performed a retrospective cohort study of children younger than 6 years old with an ED encounter at 1 of 2 large health care systems, one of which implemented routine child abuse screening. The main outcome was initial (<2 days) or subsequent (3 to 180 days) referral to CPS identifying child abuse using linked records. We compared outcomes for the 2-year period after screening was implemented to the preperiod and nonscreening EDs using generalized estimating equations to adjust for sex, age, race/ethnicity, payor and prior ED encounters and clustered by center. RESULTS: Of the 331,120 ED encounters, 41,589 (12.6%) occurred at screening EDs during the screening period. Screening was completed in 34,272 (82%) and was positive in 188 (0.45%). Overall, 7,623 encounters (2.3%) had a subsequent referral, of which 589 (0.2%) identified moderate or severe abuse. ED screening did not change initial (adjusted odds ratio [aOR]=1.01, 95% confidence interval [CI] 0.89 to 1.15) or subsequent referral to CPS when compared to the prescreening period (aOR=1.05, 95% CI 0.9 to 1.18) or to the nonscreening EDs (aOR=1.06, 95% CI 0.92 to 1.21). CONCLUSION: Routine screening did not affect initial or subsequent referrals to CPS.

11.
Nat Astron ; 8(6): 774-785, 2024.
Article in English | MEDLINE | ID: mdl-38912294

ABSTRACT

Identifying the sites of r-process nucleosynthesis, a primary mechanism of heavy element production, is a key goal of astrophysics. The discovery of the brightest gamma-ray burst (GRB) to date, GRB 221009A, presented an opportunity to spectroscopically test the idea that r-process elements are produced following the collapse of rapidly rotating massive stars. Here we present James Webb Space Telescope observations of GRB 221009A obtained +168 and +170 rest-frame days after the gamma-ray trigger, and demonstrate that they are well described by a SN 1998bw-like supernova (SN) and power-law afterglow, with no evidence for a component from r-process emission. The SN, with a nickel mass of approximately 0.09 M ⊙, is only slightly fainter than the brightness of SN 1998bw at this phase, which indicates that the SN is not an unusual GRB-SN. This demonstrates that the GRB and SN mechanisms are decoupled and that highly energetic GRBs are not likely to produce significant quantities of r-process material, which leaves open the question of whether explosions of massive stars are key sources of r-process elements. Moreover, the host galaxy of GRB 221009A has a very low metallicity of approximately 0.12 Z ⊙ and strong H2 emission at the explosion site, which is consistent with recent star formation, hinting that environmental factors are responsible for its extreme energetics.

12.
Hum Genomics ; 18(1): 70, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38909264

ABSTRACT

INTRODUCTION: We previously identified a genetic subtype (C4) of type 2 diabetes (T2D), benefitting from intensive glycemia treatment in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. Here, we characterized the population of patients that met the C4 criteria in the UKBiobank cohort. RESEARCH DESIGN AND METHODS: Using our polygenic score (PS), we identified C4 individuals in the UKBiobank and tested C4 status with risk of developing T2D, cardiovascular disease (CVD) outcomes, and differences in T2D medications. RESULTS: C4 individuals were less likely to develop T2D, were slightly older at T2D diagnosis, had lower HbA1c values, and were less likely to be prescribed T2D medications (P < .05). Genetic variants in MAS1 and IGF2R, major components of the C4 PS, were associated with fewer overall T2D prescriptions. CONCLUSION: We have confirmed C4 individuals are a lower risk subpopulation of patients with T2D.


Subject(s)
Diabetes Mellitus, Type 2 , Multifactorial Inheritance , Humans , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/pathology , Diabetes Mellitus, Type 2/epidemiology , Male , Female , Middle Aged , United Kingdom/epidemiology , Multifactorial Inheritance/genetics , Aged , Phenotype , Cardiovascular Diseases/genetics , Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/epidemiology , Genetic Predisposition to Disease , Glycated Hemoglobin/metabolism , Glycated Hemoglobin/genetics , Biological Specimen Banks , Polymorphism, Single Nucleotide/genetics
13.
World Neurosurg ; 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38909749

ABSTRACT

BACKGROUND: Medical students are increasingly seeking out research opportunities to build their skills and network with future colleagues. Medical student-led conferences are an excellent endeavor to achieve this goal. METHODS: The American Association of Neurological Surgeons (AANS) student chapter at the Donald and Barbara Zucker School of Medicine at Hofstra/Northwell designed an in-person medical student research symposium alongside the Northwell Health Department of Neurosurgery. Post-conference feedback forms were sent out digitally to student attendees to evaluate event planning and execution and responses were given on a scale of 1-5 (5 being the highest score). RESULTS: In December 2023, the Northeast Medical Student Research Symposium (NMSRS) was held with over 80 participants and 52 medical student presenters. Keynote speakers delivered lectures geared towards students interested in neurosurgery and neuroscience research, followed by an interactive poster board session and resident/attending networking dinner. After the conference, students affirmed that they learned more about neuroscience research after the event (mean: 4.3), were more inclined to attend other neuroscience research events in the future (mean: 4.7), and would attend this event if held next year (mean: 4.8). The poster sessions (mean: 4.75) and keynote lectures (mean: 5) were the highest rated events, while the resident/attending networking dinner (mean: 3.6) was a potential area for improvement. CONCLUSION: Regional in-person conferences are an excellent way to foster interest in neurosurgery and neuroscience research, network with like-minded peers, and prepare students for presentations at national meetings.

14.
J Dairy Sci ; 2024 May 31.
Article in English | MEDLINE | ID: mdl-38825128

ABSTRACT

Dominance hierarchies are known for mitigating conflicts and guiding priority of access to limited resources in gregarious animals. The dominance hierarchy of dairy cows is typically investigated using agonistic interactions, often monitored at the feed bunk right after fresh feed delivery when competition is high resulting in frequent interactions. Yet, the outcome of agonistic interactions during times of high competition may be more influenced by cows' high valuation of fresh feed than their intrinsic attributes, such that the dominance hierarchy constructed using agonistic interactions under high versus low competition times might differ. We tested how the structure of the dominance hierarchy changes in relation to different levels of competition in a dynamic group of 48 lactating dairy cows over 10 mo, with 6 cows exchanged every 16 d for a total of 159 cows. Using a validated algorithm we continuously detected the actor and reactor of replacement behaviors in 30 feed bins as cows competed for feed. We also calculated the percentage of occupied feed bins to characterize competition at the moment of each replacement. These data were combined to create hierarchies using Elo ratings, separately for 25 occupancy levels ranging from 13% to 100%. For each 1% rise in feeder occupancy, hierarchy steepness fell by 2.41 × 10-3 ± 9.71 × 10-5 (SE), and the percentage of dyads where both cows replaced each other rose by 0.13% ± 0.01%. At the highest feeder occupancy level in comparison to the lowest one, we observed 7.57% more dyads in which the dominant individual (those won more interactions at the lowest feeder occupancy) started to lose proportionally more. The magnitude of decrease in the winning rate of the dominant individual in those dyads also got amplified by 1.06 × 10-3% ± 1.37 × 10-4% (SE) for each 1% increase in feeder occupancy. These findings illustrate how inferred hierarchies vary with competition, with high competition flattening the hierarchy due to increased success of subordinate animals. We suggest that during heightened competition, increased valuation of resources can affect competitive success more than the individual's intrinsic dominance attributes. We recommend against calculating dominance hierarchies based on agonistic interactions during periods of high competition alone, and more generally urge researchers to differentiate agonistic interactions based on context when constructing dominance hierarchies.

15.
Cogn Neurodyn ; 18(3): 795-811, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38826646

ABSTRACT

Theta-gamma coupling (TGC) is a neurophysiological process that supports working memory. Working memory is associated with other clinical and biological features. The extent to which TGC is associated with these other features and whether it contributes to working memory beyond these features is unknown. Two-hundred-and-three older participants at risk for Alzheimer's dementia-98 with mild cognitive impairment (MCI), 39 with major depressive disorder (MDD) in remission, and 66 with MCI and MDD (MCI + MDD)-completed a clinical assessment, N-back-EEG, and brain MRI. Among them, 190 completed genetic testing, and 121 completed [11C] Pittsburgh Compound B ([11C] PIB) PET imaging. Hierarchical linear regressions were used to assess whether TGC is associated with demographic and clinical variables; Alzheimer's disease-related features (APOE ε4 carrier status and ß-amyloid load); and structural features related to working memory. Then, linear regressions were used to assess whether TGC is associated with 2-back performance after accounting for these features. Other than age, TGC was not associated with any non-neurophysiological features. In contrast, TGC (ß = 0.27; p = 0.006), age (ß = - 0.29; p = 0.012), and parietal cortical thickness (ß = 0.24; p = 0.020) were associated with 2-back performance. We also examined two other EEG features that are linked to working memory-theta event-related synchronization and alpha event-related desynchronization-and found them not to be associated with any feature or performance after accounting for TGC. Our findings suggest that TGC is a process that is independent of other clinical, genetic, neurochemical, and structural variables, and supports working memory in older adults at risk for dementia. Supplementary Information: The online version contains supplementary material available at 10.1007/s11571-023-09938-y.

16.
Pediatr Neurol ; 157: 5-13, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38833907

ABSTRACT

BACKGROUND: Congenital myasthenic syndromes (CMS) are a group of inherited neuromuscular junction (NMJ) disorders arising from gene variants encoding diverse NMJ proteins. Recently, the VAMP1 gene, responsible for encoding the vesicle-associated membrane protein 1 (VAMP1), has been associated with CMS. METHODS: This study presents a characterization of five new individuals with VAMP1-related CMS, providing insights into the phenotype. RESULTS: The individuals with VAMP1-related CMS exhibited early disease onset, presenting symptoms prenatally or during the neonatal period, alongside severe respiratory involvement and feeding difficulties. Generalized weakness at birth was a common feature, and none of the individuals achieved independent walking ability. Notably, all cases exhibited scoliosis. The clinical course remained stable, without typical exacerbations seen in other CMS types. The response to anticholinesterase inhibitors and salbutamol was only partial, but the addition of 3,4-diaminopyridine (3,4-DAP) led to significant and substantial improvements, suggesting therapeutic benefits of 3,4-DAP for managing VAMP1-related CMS symptoms. Noteworthy is the identification of the VAMP1 (NM_014231.5): c.340delA; p.Ile114SerfsTer72 as a founder variant in the Iberian Peninsula and Latin America. CONCLUSIONS: This study contributes valuable insights into VAMP1-related CMS, emphasizing their early onset, arthrogryposis, facial and generalized weakness, respiratory involvement, and feeding difficulties. Furthermore, the potential efficacy of 3,4-DAP as a useful therapeutic option warrants further exploration. The findings have implications for clinical management and genetic counseling in affected individuals. Additional research is necessary to elucidate the long-term outcomes of VAMP1-related CMS.

17.
J Anim Ecol ; 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38847240

ABSTRACT

Food webs depict the tangled web of trophic interactions associated with the functioning of an ecosystem. Understanding the mechanisms providing stability to these food webs is therefore vital for conservation efforts and the management of natural systems. Here, we first characterised a tropical stream meta-food web and five individual food webs using a Bayesian Hierarchical approach unifying three sources of information (gut content analysis, literature compilation and stable isotope data). With data on population-level biomass and individually measured body mass, we applied a bioenergetic model and assessed food web stability using a Lotka-Volterra system of equations. We then assessed the resilience of the system to individual species extinctions using simulations and investigated the network patterns associated with systems with higher stability. The model resulted in a stable meta-food web with 307 links among the 61 components. At the regional scale, 70% of the total energy flow occurred through a set of 10 taxa with large variation in body masses. The remaining 30% of total energy flow relied on 48 different taxa, supporting a significant dependency on a diverse community. The meta-food web was stable against individual species extinctions, with a higher resilience in food webs harbouring omnivorous fish species able to connect multiple food web compartments via weak, non-specialised interactions. Moreover, these fish species contributed largely to the spatial variation among individual food webs, suggesting that these species could operate as mobile predators connecting different streams and stabilising variability at the regional scale. Our results outline two key mechanisms of food web stability operating in tropical streams: (i) the diversity of species and body masses buffering against random and size-dependent disturbances and (ii) high regional diversity and weak omnivorous interactions of predators buffering against local stochastic variation in species composition. These mechanisms rely on high local and regional biodiversity in tropical streams, which is known to be strongly affected by human impacts. Therefore, an urgent challenge is to understand how the ongoing systematic loss of diversity jeopardises the stability of stream food webs in human-impacted landscapes.


As teias alimentares representam um emaranhado de interações tróficas associadas ao funcionamento de um ecossistema. Compreender os mecanismos que proporcionam estabilidade a estas teias alimentares é, portanto, vital para os esforços de conservação e gestão dos sistemas naturais. Aqui, primeiro caracterizamos uma meta teia alimentar de riachos tropicais e cinco teias alimentares individuais usando uma abordagem hierárquica Bayesiana unificando três fontes de informação (análise de conteúdo estomacal, compilação de literatura, dados de isótopos estáveis). Com dados sobre biomassa em nível populacional e massa corporal medida individualmente, aplicamos um modelo bioenergético e avaliamos a estabilidade da cadeia alimentar usando um sistema de equações Lotka­Volterra. Em seguida, avaliamos a resiliência do sistema às extinções de espécies individuais usando simulações e investigamos os padrões de rede associados a sistemas com maior estabilidade. O modelo resultou em uma meta teia alimentar estável com 307 ligações entre os 61 componentes. Na escala regional, 70% do fluxo total de energia ocorreu através de um conjunto de dez taxa com grande variação nas massas corporais. Os restantes 30% do fluxo total de energia dependiam de 47 taxa diferentes, apoiando uma dependência significativa de uma comunidade diversificada. A meta teia alimentar foi estável contra extinções de espécies individuais, com uma maior resiliência em teias alimentares que abrigam espécies de peixes onívoros capazes de conectar múltiplos compartimentos da teia alimentar através de interações fracas e não especializadas. Além disso, estas espécies de peixes contribuíram amplamente para a variação espacial entre as cadeias alimentares individuais, sugerindo que estas espécies poderiam operar como predadores móveis conectando diferentes riachos e estabilizando a variabilidade à escala regional. Nossos resultados descrevem dois mecanismos principais de estabilidade da cadeia alimentar operando em riachos tropicais: (i) a diversidade de espécies e massas corporais que protegem contra distúrbios aleatórios e dependentes do tamanho (ii) alta diversidade regional e fracas interações onívoras de predadores que protegem contra a variação estocástica local na composição de espécies. Estes mecanismos dependem de uma elevada biodiversidade local e regional em riachos tropicais, que são conhecidos por serem fortemente afetados pelos impactos humanos. Portanto, um desafio urgente é compreender como a contínua perda sistemática de diversidade põe em risco a estabilidade das teias alimentares em paisagens impactadas pelo homem.

18.
Am J Med ; 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38876331

ABSTRACT

OBJECTIVE: We aimed to evaluate the safety and efficacy of antithrombotic strategies by age in patients with atrial fibrillation and acute coronary syndrome and/or percutaneous coronary intervention in AUGUSTUS. METHODS: Patients were stratified into 3 age groups: <65, 65-74, and ≥75 years. Outcomes of interest were major or clinically relevant non-major bleeding, major bleeding, death or rehospitalization, and ischemic events. Treatment effects of apixaban vs. vitamin K antagonist (VKA) and aspirin vs. placebo were assessed across age groups using Cox models. RESULTS: Of 4614 patients, 1267 (27.5%) were <65, 1802 (39.0%) were 65-74, and 1545 (33.5%) were ≥75 years. Apixaban was associated with lower rates of major or clinically relevant non-major bleeding than VKA (<65: HR 0.69 [0.47-1.00]; 65-74: HR 0.57 [0.43-0.75]; ≥75: HR 0.81 [0.63-1.04]). Death or hospitalization occurred less often with apixaban, regardless of age. No differences were observed in rates of ischemic events between apixaban and VKA according to age. Aspirin was associated with higher rates of bleeding than placebo (<65: HR 1.67 [1.15-2.43]; 65-74: HR 2.32 [1.73-3.10]; ≥75: HR 1.69 [1.31-2.19]). Rates of death or rehospitalization and ischemic events were similar among patients receiving aspirin or placebo across age groups. CONCLUSIONS: Apixaban was associated with greater absolute reduction in bleeding than VKA in older age groups, reflecting their higher hemorrhagic risk. Aspirin increased bleeding in all age groups vs. placebo. Our findings support the use of apixaban plus a purinergic receptor P2Y12(P2Y12) inhibitor without aspirin in patients with atrial fibrillation and recent acute coronary syndrome/percutaneous coronary intervention, regardless of age.

20.
Prev Med ; 185: 108034, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38857770

ABSTRACT

BACKGROUND: Scaling up overdose education and naloxone distribution (OEND) and medications for opioid use disorder (MOUD) is needed to reduce opioid overdose deaths, but barriers are pervasive. This study examines whether the Communities That HEAL (CTH) intervention reduced perceived barriers to expanding OEND and MOUD in healthcare/behavioral health, criminal-legal, and other/non-traditional venues. METHODS: The HEALing (Helping End Addiction Long-Term®) Communities Study is a parallel, wait-list, cluster randomized trial testing the CTH intervention in 67 communities in the United States. Surveys administered to coalition members and key stakeholders measured the magnitude of perceived barriers to scaling up OEND and MOUD in November 2019-January 2020, May-June 2021, and May-June 2022. Multilevel linear mixed models compared Wave 1 (intervention) and Wave 2 (wait-list control) respondents. Interactions by rural/urban status and research site were tested. RESULTS: Wave 1 respondents reported significantly greater reductions in mean scores for three outcomes: perceived barriers to scaling up OEND in Healthcare/Behavioral Health Venues (-0.26, 95% confidence interval, CI: -0.48, -0.05, p = 0.015), OEND in Other/Non-traditional Venues (-0.53, 95% CI: - 0.84, -0.22, p = 0.001) and MOUD in Other/Non-traditional Venues (-0.34, 95% CI: -0.62, -0.05, p = 0.020). There were significant interactions by research site for perceived barriers to scaling up OEND and MOUD in Criminal-Legal Venues. There were no significant interactions by rural/urban status. DISCUSSION: The CTH Intervention reduced perceived barriers to scaling up OEND and MOUD in certain venues, with no difference in effectiveness between rural and urban communities. More research is needed to understand facilitators and barriers in different venues.

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