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1.
Nature ; 594(7862): 217-222, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33910228

RESUMEN

Fluoroalkyl groups profoundly affect the physical properties of pharmaceuticals and influence almost all metrics associated with their pharmacokinetic and pharmacodynamic profile1-4. Drug candidates increasingly contain trifluoromethyl (CF3) and difluoromethyl (CF2H) groups, and the same trend in agrochemical development shows that the effect of fluoroalkylation translates across human, insect and plant life5,6. New fluoroalkylation reactions have undoubtedly stimulated this shift; however, methods that directly convert C-H bonds into C-CF2X groups (where X is F or H) in complex drug-like molecules are rare7-13. Pyridines are the most common aromatic heterocycles in pharmaceuticals14, but only one approach-via fluoroalkyl radicals-is viable for achieving pyridyl C-H fluoroalkylation in the elaborate structures encountered during drug development15-17. Here we develop a set of bench-stable fluoroalkylphosphines that directly convert the C-H bonds in pyridine building blocks, drug-like fragments and pharmaceuticals into fluoroalkyl derivatives. No preinstalled functional groups or directing groups are required. The reaction tolerates a variety of sterically and electronically distinct pyridines, and is exclusively selective for the 4-position in most cases. The reaction proceeds through initial formation of phosphonium salts followed by sp2-sp3 coupling of phosphorus ligands-an underdeveloped manifold for forming C-C bonds.


Asunto(s)
Carbono/química , Flúor/química , Hidrógeno/química , Fósforo/química , Piridinas/química , Alquilación , Animales , Humanos , Ligandos , Preparaciones Farmacéuticas/química , Farmacocinética , Fosfinas/química
2.
Immunol Rev ; 320(1): 147-165, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37415280

RESUMEN

Cell therapies are powerful technologies in which human cells are reprogrammed for therapeutic applications such as killing cancer cells or replacing defective cells. The technologies underlying cell therapies are increasing in effectiveness and complexity, making rational engineering of cell therapies more difficult. Creating the next generation of cell therapies will require improved experimental approaches and predictive models. Artificial intelligence (AI) and machine learning (ML) methods have revolutionized several fields in biology including genome annotation, protein structure prediction, and enzyme design. In this review, we discuss the potential of combining experimental library screens and AI to build predictive models for the development of modular cell therapy technologies. Advances in DNA synthesis and high-throughput screening techniques enable the construction and screening of libraries of modular cell therapy constructs. AI and ML models trained on this screening data can accelerate the development of cell therapies by generating predictive models, design rules, and improved designs.


Asunto(s)
Inteligencia Artificial , Tratamiento Basado en Trasplante de Células y Tejidos , Humanos
3.
Proc Natl Acad Sci U S A ; 120(42): e2306317120, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37812699

RESUMEN

Space weather, including solar storms, can impact Earth by disturbing the geomagnetic field. Despite the known dependence of birds and other animals on geomagnetic cues for successful seasonal migrations, the potential effects of space weather on organisms that use Earth's magnetic field for navigation have received little study. We tested whether space weather geomagnetic disturbances are associated with disruptions to bird migration at a macroecological scale. We leveraged long-term radar data to characterize the nightly migration dynamics of the nocturnally migrating North American avifauna over 22 y. We then used concurrent magnetometer data to develop a local magnetic disturbance index associated with each radar station (ΔBmax), facilitating spatiotemporally explicit analyses of the relationship between migration and geomagnetic disturbance. After controlling for effects of atmospheric weather and spatiotemporal patterns, we found a 9 to 17% decrease in migration intensity in both spring and fall during severe space weather events. During fall migration, we also found evidence for decreases in effort flying against the wind, which may represent a depression of active navigation such that birds drift more with the wind during geomagnetic disturbances. Effort flying against the wind in the fall was most reduced under both overcast conditions and high geomagnetic disturbance, suggesting that a combination of obscured celestial cues and magnetic disturbance may disrupt navigation. Collectively, our results provide evidence for community-wide avifaunal responses to geomagnetic disturbances driven by space weather during nocturnal migration.


Asunto(s)
Migración Animal , Tiempo (Meteorología) , Animales , Migración Animal/fisiología , Aves/fisiología , Estaciones del Año , Viento
4.
Proc Natl Acad Sci U S A ; 119(14): e2112336119, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35349336

RESUMEN

SignificanceOur full-scale comparison of Africa and South America's lowland tropical tree floras shows that both Africa and South America's moist and dry tree floras are organized similarly: plant families that are rich in tree species on one continent are also rich in tree species on the other continent, and these patterns hold across moist and dry environments. Moreover, we confirm that there is an important difference in tree species richness between the two continents, which is linked to a few families that are exceptionally diverse in South American moist forests, although dry formations also contribute to this difference. Plant families only present on one of the two continents do not contribute substantially to differences in tree species richness.


Asunto(s)
Árboles , Clima Tropical , Biodiversidad , Bosques , Plantas , América del Sur
5.
Proc Natl Acad Sci U S A ; 119(35): e2121333119, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35994645

RESUMEN

SNPs associated with human stroke risk have been identified in the intergenic region between Forkhead family transcription factors FOXF2 and FOXQ1, but we lack a mechanism for the association. FoxF2 is expressed in vascular mural pericytes and is important for maintaining pericyte number and stabilizing small vessels in zebrafish. The stroke-associated SNPs are located in a previously unknown transcriptional enhancer for FOXF2, functional in human cells and zebrafish. We identify critical enhancer regions for FOXF2 gene expression, including binding sites occupied by transcription factors ETS1, RBPJ, and CTCF. rs74564934, a stroke-associated SNP adjacent to the ETS1 binding site, decreases enhancer function, as does mutation of RPBJ sites. rs74564934 is significantly associated with the increased risk of any stroke, ischemic stroke, small vessel stroke, and elevated white matter hyperintensity burden in humans. Foxf2 has a conserved function cross-species and is expressed in vascular mural pericytes of the vessel wall. Thus, stroke-associated SNPs modulate enhancer activity and expression of a regulator of vascular stabilization, FOXF2, thereby modulating stroke risk.


Asunto(s)
Factores de Transcripción Forkhead , Pericitos , Accidente Cerebrovascular , Animales , ADN Intergénico/genética , ADN Intergénico/metabolismo , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Variación Estructural del Genoma/genética , Humanos , Pericitos/metabolismo , Polimorfismo de Nucleótido Simple , Riesgo , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/metabolismo , Activación Transcripcional/genética
6.
J Clin Microbiol ; : e0035924, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904385

RESUMEN

Medical microbiologists, defined as doctoral-level laboratory directors with subspecialty training in medical microbiology, lead the clinical laboratory operations through activities such as clinical consultations, oversight of diagnostic testing menu, institutional leadership, education, and scholastic activities. However, unlike their clinical colleagues, medical microbiologists are largely unable to bill for clinical consultations performed within the hospital and, therefore, unable to generate relative value units or a similar quantifiable metric. As hospital budgets tighten and justification of staffing becomes a necessity, this may present a challenge to the medical microbiologist attempting to prove their value to the organization. To aid in providing tangible data, the Personnel Standards and Workforce subcommittee of the American Society for Microbiology conducted a multi-center study across seven medical centers to document clinical consultations and their impact. Consults were generated equally from internal (laboratory-based) and external (hospital-based) parties, with the majority directly impacting patient management. Near universal acceptance of the medical microbiologist's recommendation highlights the worth derived from their expertise. External consults required more time commitment from the medical microbiologist than internal consults, although both presented ample opportunity for secondary value, including impact through stewardship, education, clinical guidance, and cost reduction. This study is a description of the content and impact of consultations that underscore the importance of the medical microbiologist as a key member of the healthcare team. IMPORTANCE: Medical microbiologists are invaluable to the clinical microbiology laboratory and the healthcare system as a whole. However, as medical microbiologists do not regularly generate relative value units, capturing and quantifying the value provided is challenging. As hospital budgets tighten, justification of staffing becomes a necessity. To aid in providing tangible data, the Personnel Standards and Workforce subcommittee of the American Society for Microbiology conducted a multi-center study across seven medical centers to document clinical consultations and their impact. To our knowledge, this is the first study to provide detailed evaluation of the consultative value provided by medical microbiologists.

7.
Mol Ecol ; 33(2): e17218, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38038696

RESUMEN

Host-microbe interactions are increasingly recognized as important drivers of organismal health, growth, longevity and community-scale ecological processes. However, less is known about how genetic variation affects hosts' associated microbiomes and downstream phenotypes. We demonstrate that sunflower (Helianthus annuus) harbours substantial, heritable variation in microbial communities under field conditions. We show that microbial communities co-vary with heritable variation in resistance to root infection caused by the necrotrophic pathogen Sclerotinia sclerotiorum and that plants grown in autoclaved soil showed almost complete elimination of pathogen resistance. Association mapping suggests at least 59 genetic locations with effects on both microbial relative abundance and Sclerotinia resistance. Although the genetic architecture appears quantitative, we have elucidated previously unexplained genetic variation for resistance to this pathogen. We identify new targets for plant breeding and demonstrate the potential for heritable microbial associations to play important roles in defence in natural and human-altered environments.


Asunto(s)
Fitomejoramiento , Rizosfera , Humanos , Fenotipo , Plantas , Microbiología del Suelo , Raíces de Plantas/genética , Raíces de Plantas/microbiología
8.
Dis Colon Rectum ; 67(7): 920-928, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38498775

RESUMEN

BACKGROUND: Pathologic complete response after neoadjuvant chemoradiotherapy for rectal cancer is associated with improved survival. It is unclear whether residual carcinoma in situ portends a similar outcome. OBJECTIVE: To compare the survival of patients with locally advanced rectal cancer who received neoadjuvant therapy and achieved pathologic carcinoma in situ versus pathologic complete response. DESIGN: Retrospective cohort study. SETTING: National public database. PATIENTS: A total of 4594 patients in the National Cancer Database from 2006 to 2016 with locally advanced rectal cancer who received neoadjuvant therapy, underwent surgery, and had node-negative ypTis or ypT0 on final pathology were included. Of these, 4321 patients (94.1%) had ypT0 and 273 (5.9%) had ypTis on final pathology. MAIN OUTCOME MEASURE: Overall survival. RESULTS: The median age was 60 years, and 1822 patients (39.7%) were women. On initial staging, 54.5% (n = 2503) had stage II disease and 45.5% (n = 2091) had stage III disease. The ypTis group had decreased overall survival compared to the ypT0 group (HR 1.42; 95% CI, 1.04-1.95; p = 0.028). Other factors associated with decreased overall survival were older age at diagnosis, increasing Charlson-Deyo score, and poorly differentiated tumor grade. Variables associated with improved survival were female sex, private insurance, and receipt of both neoadjuvant and adjuvant chemotherapy. For the total cohort, there was no difference in survival between clinical stage II and stage III. LIMITATIONS: Standard therapy versus total neoadjuvant therapy could not be abstracted. Overall survival was defined as the time from surgery to death from any cause or last contact, allowing for some erroneously misclassified deaths. CONCLUSIONS: ypTis is associated with worse overall survival than ypT0 for patients with locally advanced rectal cancer who receive neoadjuvant chemoradiotherapy followed by surgery. For this cohort, clinical stage was not a significant predictor of survival. Prospective trials comparing survival for these pathologic outcomes are needed. See Video Abstract . SUPERVIVENCIA DEL CNCER DE RECTO PARA EL CARCINOMA RESIDUAL IN SITU VS RESPUESTA PATOLGICA COMPLETA DESPUS DE LA TERAPIA NEOADYUVANTE: ANTECEDENTESLa respuesta patológica completa después de la quimiorradioterapia neoadyuvante para el cáncer de recto se asocia con una mayor supervivencia. No está claro si el carcinoma residual in situ presagia un resultado similar.OBJETIVOComparar la supervivencia de pacientes con cáncer de recto localmente avanzado que recibieron terapia neoadyuvante y lograron un carcinoma patológico in situ versus una respuesta patológica completa.DISEÑOEstudio de cohorte retrospectivo.ESCENARIOBase de datos pública nacional.PACIENTESSe incluyeron 4,594 pacientes de la Base de Datos Nacional de Cáncer de 2006 a 2016 con cáncer de recto localmente avanzado que recibieron terapia neoadyuvante, fueron sometidos a cirugía y tuvieron ganglios negativos, ypTis o ypT0 en el reporte patológico final. 4.321 (94,1%) tuvieron ypT0 y 273 (5,9%) tuvieron ypTis en el reporte final.PRINCIPALES MEDIDAS DE RESULTADOSupervivencia general.RESULTADOSLa mediana de edad fue de 60 años. 1.822 pacientes (39,7%) fueron mujeres. El 54,5% (n = 2.503) tuvo la enfermedad en estadio II y el 45,5% (n = 2.091) tuvo la enfermedad en estadio III según la estadificación inicial. El grupo ypTis tuvo una supervivencia general reducida en comparación con el grupo ypT0 (HR 1,42, IC 95 % 1,04-1,95, p = 0,028). Otros factores asociados con una menor supervivencia general fueron una edad más avanzada al momento del diagnóstico, un aumento de la puntuación de Charlson-Deyo y un grado tumoral poco diferenciado. Las variables asociadas con una mejor supervivencia fueron el sexo femenino, el seguro privado y la recepción de quimioterapia neoadyuvante y adyuvante. Para la cohorte total, no hubo diferencias en la supervivencia entre el estadio clínico 2 y el estadio 3.LIMITACIONESNo se pudo resumir el tratamiento estándar versus el tratamiento neoadyuvante total. La supervivencia general se definió como el tiempo transcurrido desde la cirugía hasta la muerte por cualquier causa o último contacto, lo que permite algunas muertes erróneamente clasificadas.CONCLUSIONESypTis se asocia con una peor supervivencia general que ypT0 en pacientes con cáncer de recto localmente avanzado que reciben quimiorradioterapia neoadyuvante seguida de cirugía. Para esta cohorte, el estadio clínico no fue un predictor significativo de supervivencia. Se necesitan ensayos prospectivos que comparen la supervivencia de estos resultados patológicos. ( Traducción-Dr Osvaldo Gauto ).


Asunto(s)
Terapia Neoadyuvante , Estadificación de Neoplasias , Neoplasia Residual , Neoplasias del Recto , Humanos , Masculino , Femenino , Persona de Mediana Edad , Neoplasias del Recto/terapia , Neoplasias del Recto/patología , Neoplasias del Recto/mortalidad , Terapia Neoadyuvante/métodos , Terapia Neoadyuvante/estadística & datos numéricos , Estudios Retrospectivos , Anciano , Tasa de Supervivencia , Proctectomía , Respuesta Patológica Completa
9.
J Anim Ecol ; 93(7): 836-848, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38741512

RESUMEN

Climate change is altering the timing of seasonal events for many taxa. There is limited understanding of how northward/southward songbird migration follows or is limited by the latitudinal progression of seasonal transitions. Consistent environmental conditions that migrating birds encounter across latitudes likely represent or correlate with important resources or limiting factors for migration. We tested whether migratory passage-observed via radar-consistently tracked land surface variables and phenophases across latitudes in the US Central Flyway in both spring and fall. The daily temperatures, precipitation and vegetation greenness occurring on 10%, 50% and 90% cumulative passage dates changed substantially with latitude, indicating that most migrants experienced rapidly changing conditions as they headed north or south. Temperature did not limit the progression of migration in either season. Peak spring migration in the southern US occurred nearly 40 days after the spring green wave, the northward progression of vegetation growth, but nearly caught up to green-up at 48° N. Spring migration phenology may have evolved to prioritize earlier arrival for breeding. Across all latitudes, peak fall migration coincided with the same land surface phenophase, an interval of 26 days prior to dormancy onset. Migrants may rely on phenological events in vegetation during fall stopovers. Considering that (a) migratory passage tracked fall land surface phenology across latitudes at a continental scale, (b) previous studies at local scales have demonstrated the importance of fruit during fall migratory stopover and (c) fruiting phenology in North America is occurring later over time while fall migration is advancing, the potential for mismatch between fall fruiting and bird migration phenology urgently needs further investigation.


Asunto(s)
Migración Animal , Estaciones del Año , Pájaros Cantores , Animales , Pájaros Cantores/fisiología , Estados Unidos , Cambio Climático , Temperatura
10.
Proc Natl Acad Sci U S A ; 118(9)2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33627405

RESUMEN

T cells experience complex temporal patterns of stimulus via receptor-ligand-binding interactions with surrounding cells. From these temporal patterns, T cells are able to pick out antigenic signals while establishing self-tolerance. Although features such as duration of antigen binding have been examined, our understanding of how T cells interpret signals with different frequencies or temporal stimulation patterns is relatively unexplored. We engineered T cells to respond to light as a stimulus by building an optogenetically controlled chimeric antigen receptor (optoCAR). We discovered that T cells respond to minute-scale oscillations of activation signal by stimulating optoCAR T cells with tunable pulse trains of light. Systematically scanning signal oscillation period from 1 to 150 min revealed that expression of CD69, a T cell activation marker, reached a local minimum at a period of ∼25 min (corresponding to 5 to 15 min pulse widths). A combination of inhibitors and genetic knockouts suggest that this frequency filtering mechanism lies downstream of the Erk signaling branch of the T cell response network and may involve a negative feedback loop that diminishes Erk activity. The timescale of CD69 filtering corresponds with the duration of T cell encounters with self-peptide-presenting APCs observed via intravital imaging in mice, indicating a potential functional role for temporal filtering in vivo. This study illustrates that the T cell signaling machinery is tuned to temporally filter and interpret time-variant input signals in discriminatory ways.


Asunto(s)
Antígenos CD/genética , Antígenos de Diferenciación de Linfocitos T/genética , Lectinas Tipo C/genética , Fototransducción/genética , Receptores Quiméricos de Antígenos/genética , Autotolerancia , Linfocitos T/inmunología , Animales , Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/inmunología , Brefeldino A/farmacología , Ingeniería Celular/métodos , Retroalimentación Fisiológica , Regulación de la Expresión Génica , Receptor 2 Celular del Virus de la Hepatitis A/genética , Receptor 2 Celular del Virus de la Hepatitis A/inmunología , Humanos , Interferón gamma/genética , Interferón gamma/inmunología , Células K562 , Lectinas Tipo C/inmunología , Luz , Activación de Linfocitos/efectos de los fármacos , Ratones , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/inmunología , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/inmunología , Monensina/farmacología , Optogenética/métodos , Cultivo Primario de Células , Proteína Tirosina Fosfatasa no Receptora Tipo 22/deficiencia , Proteína Tirosina Fosfatasa no Receptora Tipo 22/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 22/inmunología , Receptores Quiméricos de Antígenos/inmunología , Linfocitos T/citología , Linfocitos T/efectos de la radiación
11.
Proc Natl Acad Sci U S A ; 118(24)2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-34099553

RESUMEN

Millions of nocturnally migrating birds die each year from collisions with built structures, especially brightly illuminated buildings and communication towers. Reducing this source of mortality requires knowledge of important behavioral, meteorological, and anthropogenic factors, yet we lack an understanding of the interacting roles of migration, artificial lighting, and weather conditions in causing fatal bird collisions. Using two decades of collision surveys and concurrent weather and migration measures, we model numbers of collisions occurring at a large urban building in Chicago. We find that the magnitude of nocturnal bird migration, building light output, and wind conditions are the most important predictors of fatal collisions. The greatest mortality occurred when the building was brightly lit during large nocturnal migration events and when winds concentrated birds along the Chicago lakeshore. We estimate that halving lighted window area decreases collision counts by 11× in spring and 6× in fall. Bird mortality could be reduced by ∼60% at this site by decreasing lighted window area to minimum levels historically recorded. Our study provides strong support for a relationship between nocturnal migration magnitude and urban bird mortality, mediated by light pollution and local atmospheric conditions. Although our research focuses on a single site, our findings have global implications for reducing or eliminating a critically important cause of bird mortality.


Asunto(s)
Aves/fisiología , Migración Animal/fisiología , Animales , Chicago , Ciudades , Iluminación , Factores de Tiempo , Viento
12.
Exp Aging Res ; 50(3): 376-399, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37009776

RESUMEN

We investigated whether individuals who are good at recognizing previously presented items are also good at recognizing the context in which items were presented. We focused specifically on whether the relation between item recognition and context recognition abilities differs in younger and older adults. It has been hypothesized that context memory declines more rapidly in older adults due to an age-related deficit in associative binding or recollection. To test this hypothesis, younger and older adults were asked to remember lists of names and objects, as well as the context (i.e. their size, location, and color) that accompanied those items. Following presentation of each list, recognition tests for items and context were administered. Confirmatory factor analysis (CFA) models analyzing both item and context scores together provided no evidence of separate factors for item and context memory. Instead, the best-fitting model separated performance by item-type, regardless of context, and no differences were found in the structure of these abilities in younger and older adults. These findings are consistent with the limited previous latent variable research on context memory in aging suggesting that there is no context recognition memory ability separable from item memory in younger nor older adults. Instead, individual differences in recognition memory abilities may be specific to the domain of the studied stimulus.


Asunto(s)
Envejecimiento , Reconocimiento en Psicología , Humanos , Anciano , Recuerdo Mental
13.
Vet Surg ; 53(3): 437-446, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38078621

RESUMEN

OBJECTIVE: To investigate a left-sided fourth intercostal approach to thoracic duct (TD) ligation and unilateral subphrenic pericardiectomy in dogs. STUDY DESIGN: Retrospective computed tomography (CT) review and cadaveric study. ANIMALS: Thirteen dogs with idiopathic chylothorax and 10 canine cadavers. METHODS: A retrospective study of CT lymphangiograms in client-owned dogs with idiopathic chylothorax evaluated location and branching of the TD at the left fourth intercostal space. A cadaveric study evaluated the efficacy of TD ligation at this site. Following methylene blue mesenteric lymph node injection, TDs were identified through a left fourth intercostal thoracotomy, ligated, and sealed. Unilateral subphrenic pericardiectomy was performed through the same incision. Computed tomography scans were performed to determine the success of TD ligation. RESULTS: A review of lymphangiograms revealed a single TD in 10/13 clinical cases at the fourth intercostal space. Three cases had additional branches. Thoracic duct ligation via a left fourth intercostal thoracotomy was successful in nine out of 10 cadavers. A single branch was noted intraoperatively in six out of 10, and two branches were noted in four out of 10 cadavers. All branches were observed on the left side of the esophagus. CONCLUSION: TD ligation at the left fourth intercostal space was successfully performed in 9/10 canine cadavers and appeared feasible in a retrospective review of 10/13 clinical cases. Unilateral subphrenic pericardiectomy can also be performed via this approach. CLINICAL SIGNIFICANCE: Fewer thoracic duct branches at this location in comparison with the standard caudal location may simplify TD ligation. If elected, unilateral subphrenic pericardiectomy can be performed through the same incision. Further investigation in clinical patients is warranted.


Asunto(s)
Quilotórax , Enfermedades de los Perros , Humanos , Perros , Animales , Conducto Torácico/cirugía , Quilotórax/veterinaria , Estudios Retrospectivos , Pericardiectomía/veterinaria , Enfermedades de los Perros/cirugía , Ligadura/veterinaria , Cadáver , Azul de Metileno
14.
Proc Biol Sci ; 290(1997): 20222513, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37122248

RESUMEN

The Western Ghats (WG) mountain chain is a global biodiversity hotspot with high diversity and endemicity of woody plants. The latitudinal breadth of the WG offers an opportunity to determine the evolutionary drivers of latitudinal diversity patterns. We examined the spatial patterns of evolutionary diversity using complementary phylogenetic diversity and endemism measures. To examine if different regions of the WG serve as a museum or cradle of evolutionary diversity, we examined the distribution of 470 species based on distribution modelling and occurrence locations across the entire region. In accordance with the expectation, we found that the southern WG is both a museum and cradle of woody plant evolutionary diversity, as a higher proportion of both old and young evolutionary lineages are restricted to the southern WG. The diversity gradient is likely driven by high geo-climatic stability in the south and phylogenetic niche conservatism for moist and aseasonal sites. This is corroborated by persistent lineage nestedness at almost all evolutionary depths (10-135 million years), and a strong correlation of evolutionary diversity with drought seasonality, precipitation and topographic heterogeneity. Our results highlight the global value of the WG, demonstrating, in particular, the importance of protecting the southern WG-an engine of plant diversification and persistence.


Asunto(s)
Museos , Madera , Filogenia , Evolución Biológica , Biodiversidad
15.
New Phytol ; 237(2): 631-642, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36263711

RESUMEN

Plants are widely recognized as chemical factories, with each species producing dozens to hundreds of unique secondary metabolites. These compounds shape the interactions between plants and their natural enemies. We explore the evolutionary patterns and processes by which plants generate chemical diversity, from evolving novel compounds to unique chemical profiles. We characterized the chemical profile of one-third of the species of tropical rainforest trees in the genus Inga (c. 100, Fabaceae) using ultraperformance liquid chromatography-mass spectrometry-based metabolomics and applied phylogenetic comparative methods to understand the mode of chemical evolution. We show: each Inga species contain structurally unrelated compounds and high levels of phytochemical diversity; closely related species have divergent chemical profiles, with individual compounds, compound classes, and chemical profiles showing little-to-no phylogenetic signal; at the evolutionary time scale, a species' chemical profile shows a signature of divergent adaptation. At the ecological time scale, sympatric species were the most divergent, implying it is also advantageous to maintain a unique chemical profile from community members; finally, we integrate these patterns with a model for how chemical diversity evolves. Taken together, these results show that phytochemical diversity and divergence are fundamental to the ecology and evolution of plants.


Asunto(s)
Fabaceae , Metabolómica , Metabolismo Secundario , Filogenia , Bosque Lluvioso
16.
Glob Chang Biol ; 29(5): 1407-1419, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36397251

RESUMEN

Organisms have been shifting their timing of life history events (phenology) in response to changes in the emergence of resources induced by climate change. Yet understanding these patterns at large scales and across long time series is often challenging. Here we used the US weather surveillance radar network to collect data on the timing of communal swallow and martin roosts and evaluate the scale of phenological shifts and its potential association with temperature. The discrete morning departures of these aggregated aerial insectivores from ground-based roosting locations are detected by radars around sunrise. For the first time, we applied a machine learning algorithm to automatically detect and track these large-scale behaviors. We used 21 years of data from 12 weather surveillance radar stations in the Great Lakes region to quantify the phenology in roosting behavior of aerial insectivores at three spatial levels: local roost cluster, radar station, and across the Great Lakes region. We show that their peak roosting activity timing has advanced by 2.26 days per decade at the regional scale. Similar signals of advancement were found at the station scale, but not at the local roost cluster scale. Air temperature trends in the Great Lakes region during the active roosting period were predictive of later stages of roosting phenology trends (75% and 90% passage dates). Our study represents one of the longest-term broad-scale phenology examinations of avian aerial insectivore species responding to environmental change and provides a stepping stone for examining potential phenological mismatches across trophic levels at broad spatial scales.


Asunto(s)
Radar , Tiempo (Meteorología) , Estaciones del Año , Temperatura , Cambio Climático , Great Lakes Region
17.
J Gen Intern Med ; 38(Suppl 1): 38-44, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36864267

RESUMEN

BACKGROUND: The Providence Diabetes Collective Impact Initiative (DCII) was designed to address the clinical challenges of type 2 diabetes and the social determinants of health (SDoH) challenges that exacerbate disease impact. OBJECTIVE: We assessed the impact of the DCII, a multifaceted intervention approach to diabetes treatment that employed both clinical and SDoH strategies, on access to medical and social services. DESIGN: The evaluation employed a cohort design and used an adjusted difference-in-difference model to compare treatment and control groups. PARTICIPANTS: Our study population consisted of 1220 people (740 treatment, 480 control), aged 18-65 years old with a pre-existing type 2 diabetes diagnosis who visited one of the seven Providence clinics (three treatment and four control) in the tri-county area of Portland, Oregon, between August 2019 and November 2020. INTERVENTIONS: The DCII threaded together clinical approaches such as outreach, standardized protocols, and diabetes self-management education and SDoH strategies including social needs screening, referral to a community resource desk, and social needs support (e.g., transportation) to create a comprehensive, multi-sector intervention. MAIN MEASURES: Outcome measures included SDoH screens, diabetes education participation, HbA1c, blood pressure, and virtual and in-person primary care utilization, as well as inpatient and emergency department hospitalization. KEY RESULTS: Compared to patients at the control clinics, patients at DCII clinics saw an increase in diabetes education (15.5%, p<0.001), were modestly more likely to receive SDoH screening (4.4%, p<0.087), and had an increase in the average number of virtual primary care visits of 0.35 per member, per year (p<0.001). No differences in HbA1c, blood pressure, or hospitalization were observed. CONCLUSIONS: DCII participation was associated with improvements in diabetes education use, SDoH screening, and some measures of care utilization.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/terapia , Hemoglobina Glucada , Presión Sanguínea , Pacientes , Tamizaje Masivo , Determinantes Sociales de la Salud
18.
Theor Popul Biol ; 153: 91-101, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37451507

RESUMEN

Many species that are birthed in one location and become reproductive in another location can be treated as if in a one-dimensional habitat where dispersal is biased downstream. One example of such is planktonic larvae that disperse in coastal oceans, rivers, and streams. In these habitats, the dynamics of the dispersal are dominated by the movement of offspring in one direction and the distance between parents and offspring in the other direction does not matter. We study an idealized species with non-overlapping generations in a finite linear habitat that has no larval input from outside of the habitat and is therefore isolated from other populations. The most non-realistic assumption that we make is that there are non-overlapping generations, and this is an assumption to be considered in future work. We find that a biased dispersal in the habitat reduces the average time to the most recent common ancestor and causes the average location of the most recent common ancestor to move from the center of the habitat to the upstream edge of the habitat. Due to the decrease in the time to the most recent common ancestor and the shift of the average location to the upstream edge, the effective population size (Ne) no longer depends on the census size and is dependent on the dispersal statistics. We determine the average time and location of the most recent common ancestor as a function of the larval dispersal statistics. The location of the most recent common ancestor becomes independent of the length of the habitat and is only dependent on the location of the upstream edge and the larval dispersal statistics.


Asunto(s)
Ecosistema , Animales , Larva , Densidad de Población , Océanos y Mares
19.
Brain Behav Immun ; 107: 124-131, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36208853

RESUMEN

BACKGROUND: Inflammation can have social consequences, which may be relevant to inflammation's link with depression. The current study tests whether a typhoid vaccine increases feelings of social disconnection and avoidance behavior. METHOD: In two full-day visits at least three weeks apart, 172 postmenopausal breast cancer survivors (Stage I-IIIA) each received a typhoid capsular polysaccharide vaccination and a saline placebo injection in a random sequence. Blood was drawn prior to the injection, as well as every 90 min thereafter for 8 h to assess the inflammatory response (interleukin-6, IL-6; interleukin-1 receptor antagonist, IL-1Ra). At both visits, women completed the Social Connection Scale at 0 and 8.5 h post-vaccination as well as implicit and explicit social avoidance tasks at 7 h post-vaccination. RESULTS: The typhoid vaccine triggered rises in both inflammatory markers (ps < 0.01), but it did not impact feelings of social connection (p = .32), or performance on the implicit (p = .34) or explicit tasks (p = .37). Inflammatory rises did not predict feelings of social connection (ps > 0.64) or performance on explicit (ps > 0.73) or implicit (ps > 0.88) social avoidance tasks. CONCLUSION: Milder inflammatory stimuli may not affect social processes. Higher levels of inflammation or, relatedly, more sickness symptoms may be necessary to recapitulate prior findings of social avoidance.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Vacunas Tifoides-Paratifoides , Femenino , Humanos , Persona de Mediana Edad , Conducta Social
20.
J Surg Res ; 281: 37-44, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36115147

RESUMEN

INTRODUCTION: Preoperative endoscopic tattooing is an effective tool for intraoperative tumor localization in colon cancer. Endoscopic tattooing in rectal cancer may have unidentified benefits on lymph node yield, making it easier for pathologists to identify nodes during histopathologic assessment. There remains concern that tattoo ink may alter anatomical planes, increasing surgical difficulty. METHODS: Retrospective chart reviews from 2016 to 2021 of n = 170 patients presenting with rectal cancer were divided into two groups: with (n = 79) and without (n = 91) endoscopic tattoos. Demographics, operative details, tumor characteristics, prior chemoradiation, and pathologic details were collected. Primary outcome was total lymph node yield. Secondary outcomes were rates of adequate (> 12) nodes, margin status, and operative variables including operative time. RESULTS: No differences between pathologic stage, tumor height, high inferior mesenteric artery ligation, operative times, conversion rate, or surgical approach (open versus minimally invasive) were noted between groups. Receipt of neoadjuvant chemoradiation was less frequent in the endoscopic tattooing group (53.2% versus 76.9%, P ≤ 0.001). Total node number and rate of adequate lymph node yield were higher with endoscopic tattooing (20.5 ± 7.6 versus 16.8 ± 6.6 lymph nodes and 100.0% versus 83.5% adequate lymph node harvest, both P ≤ 0.001). Rates of positive circumferential and distal margins and complete total mesorectal excision were also similar. Regression analysis identified endoscopic tattooing (Incidence Risk Ratio 1.17, 95% confidence interval 1.04-1.31) and operative time more than 300 min (Incidence Risk Ratio 0.88, 95% confidence interval 0.77-0.99) had significant effects on lymph node harvest. Removal of patients with inadequate lymph node yield resulted in similar rates of total and positive lymph nodes. CONCLUSIONS: Endoscopic rectal tattooing is associated with increased lymph node yield (including after neoadjuvant chemoradiotherapy) without sacrificing oncologic or perioperative outcomes, although this effect is inconsistent when only considering patients with an adequate lymph node yield.


Asunto(s)
Neoplasias del Recto , Tatuaje , Humanos , Tatuaje/métodos , Escisión del Ganglio Linfático/métodos , Estudios Retrospectivos , Neoplasias del Recto/cirugía , Neoplasias del Recto/patología , Ganglios Linfáticos/cirugía , Ganglios Linfáticos/patología , Terapia Neoadyuvante , Estadificación de Neoplasias
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