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1.
Nature ; 627(8002): 73-79, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38418887

RESUMEN

By directly altering microscopic interactions, pressure provides a powerful tuning knob for the exploration of condensed phases and geophysical phenomena1. The megabar regime represents an interesting frontier, in which recent discoveries include high-temperature superconductors, as well as structural and valence phase transitions2-6. However, at such high pressures, many conventional measurement techniques fail. Here we demonstrate the ability to perform local magnetometry inside a diamond anvil cell with sub-micron spatial resolution at megabar pressures. Our approach uses a shallow layer of nitrogen-vacancy colour centres implanted directly within the anvil7-9; crucially, we choose a crystal cut compatible with the intrinsic symmetries of the nitrogen-vacancy centre to enable functionality at megabar pressures. We apply our technique to characterize a recently discovered hydride superconductor, CeH9 (ref. 10). By performing simultaneous magnetometry and electrical transport measurements, we observe the dual signatures of superconductivity: diamagnetism characteristic of the Meissner effect and a sharp drop of the resistance to near zero. By locally mapping both the diamagnetic response and flux trapping, we directly image the geometry of superconducting regions, showing marked inhomogeneities at the micron scale. Our work brings quantum sensing to the megabar frontier and enables the closed-loop optimization of superhydride materials synthesis.

2.
Ann Bot ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38833416

RESUMEN

BACKGROUND AND SCOPE: Plant functional traits are the result of natural selection to optimize carbon gain, leading to a broad spectrum of traits across environmental gradients. Among plant traits, leaf water storage capacity is paramount for plant drought resistance. We explored whether leaf-succulent taxa follow similar trait correlations as non-leaf-succulent taxa to evaluate whether both are similarly constrained by relationships between leaf water storage and climate. We tested the relationships among three leaf traits related to water storage capacity and resource use strategies in 132 species comprising three primary leaf types: succulent, sclerophyllous, and leaves with rapid returns on water investment - referred to as fast return. Correlation coefficients among specific leaf area (SLA), water mass per unit of area (WMA), and saturated water content (SWC) were tested, along with relationships between leaf trait spectra and aridity determined from species occurrence records. CONCLUSION: Both SWC and WMA at a given SLA were approximately 10-fold higher in succulent leaves than in non-succulent leaves. While SWC actually increased with SLA in non-succulent leaves, no relationship was detected between SWC and SLA in succulent leaves, although WMA decreased with SLA in all leaf types. A principal component analysis revealed that succulent-taxa occupied a widely different mean trait space than either fast-return (P < 0.0001) and sclerophyllous taxa (P < 0.0001) along the first PCA axis, that explained 63% of mean trait expression among species. However, aridity only explained 12% of the variation in PCA1 values. This study is among the first to establish a structural leaf trait spectrum in succulent leaf taxa and quantify contrasts in leaf water storage among leaf types relative to specific leaf area. Results show that trait coordination in succulent leaf taxa may not follow similar patterns as widely studied non-succulent taxa.

3.
Neurosurg Focus ; 57(1): E3, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38950434

RESUMEN

OBJECTIVE: Epidemiology provides fundamental opportunities to protect student-athlete health. The goal of this study was to describe the epidemiology of sport-related concussion (SRC) across 8 years (2015/2016-2022/2023) and compare boys' and girls' sports for SRC incidence and SRC mechanisms. METHODS: This was a retrospective cohort study performed using a statewide high school head injury surveillance system of high school student-athletes (n = 2,182,128; boys, n = 1,267,389; girls, n = 914,739). Exposures of interest included study year and boys and girls in comparable sports. Clinical incidence was calculated by dividing SRC counts in each sport by the number of participants per 100 player-seasons and presented with 95% CIs. The 2019/2020 and 2020/2021 data were included in the analysis, however caution is warranted due to the COVID-19 pandemic. Clinical incidence ratios (CIRs) were estimated for sex-comparable sports, and significance was determined if 95% CIs excluded 1.00. The authors compared mechanism of injury in boys' and girls' comparable sports with chi-square analyses (p < 0.05). RESULTS: Among 25,482 total SRCs, the overall clinical incidence of SRC for all boys and girls was 1.17 (95% CI 1.15-1.18) per 100 player-seasons across all years. Across all years, the overall clinical incidence in boys' sports was 1.34 (95% CI 1.32-1.36) per 100 player-seasons, and 0.93 (95% CI 0.91-0.95) per 100 player-seasons in girls' sports. Boys' sports with the highest clinical incidence included football, ice hockey, and wrestling. Girls' sports with the highest clinical incidence included basketball, soccer, lacrosse, competitive cheer, and gymnastics. Girls consistently had higher SRC rates relative to boys for baseball/softball, basketball, and soccer (CIR range 1.65 [95% CI 1.41-1.93] to 3.32 [95% CI 2.67-4.16]). Girls had lower SRC in lacrosse in 2015/2016 (CIR 0.63, 95% CI 0.40-0.97); no difference in 2016/2017-2020/2021, but had higher clinical incidence in 2021/2022 (CIR 1.69, 95% CI 1.18-2.44) relative to boys. In boys the most common mechanism of SRC occurred from person-to-person contact (n = 8752, 62.8%), whereas girls commonly sustained SRC from person-to-object contact (n = 2369, 33.4%) and from person-to-person contact (n = 2368, 33.4%). There were significant associations between boys' versus girls' sports and mechanism of injury within baseball/softball (χ2 = 12.71, p = 0.005); basketball (χ2 = 36.47, p < 0.001); lacrosse (χ2 = 185.15, p < 0.001); and soccer (χ2 = 122.70, p < 0.001). CONCLUSIONS: These findings can help understand the potential impact of interventions aimed at preventing or reducing SRC. Including girls' sports within this study extends research for a largely underrepresented group.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , COVID-19 , Humanos , Masculino , Femenino , Conmoción Encefálica/epidemiología , Conmoción Encefálica/prevención & control , Traumatismos en Atletas/epidemiología , Traumatismos en Atletas/prevención & control , Adolescente , Estudios Retrospectivos , Incidencia , COVID-19/prevención & control , COVID-19/epidemiología , Instituciones Académicas , Estudiantes/estadística & datos numéricos , Estudios de Cohortes , Fútbol Americano/lesiones , Atletas , Deportes , Baloncesto/lesiones
4.
Am J Bot ; 110(11): e16249, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37792319

RESUMEN

PREMISE: Bryophytes form a major component of terrestrial plant biomass, structuring ecological communities in all biomes. Our understanding of the evolutionary history of hornworts, liverworts, and mosses has been significantly reshaped by inferences from molecular data, which have highlighted extensive homoplasy in various traits and repeated bursts of diversification. However, the timing of key events in the phylogeny, patterns, and processes of diversification across bryophytes remain unclear. METHODS: Using the GoFlag probe set, we sequenced 405 exons representing 228 nuclear genes for 531 species from 52 of the 54 orders of bryophytes. We inferred the species phylogeny from gene tree analyses using concatenated and coalescence approaches, assessed gene conflict, and estimated the timing of divergences based on 29 fossil calibrations. RESULTS: The phylogeny resolves many relationships across the bryophytes, enabling us to resurrect five liverwort orders and recognize three more and propose 10 new orders of mosses. Most orders originated in the Jurassic and diversified in the Cretaceous or later. The phylogenomic data also highlight topological conflict in parts of the tree, suggesting complex processes of diversification that cannot be adequately captured in a single gene-tree topology. CONCLUSIONS: We sampled hundreds of loci across a broad phylogenetic spectrum spanning at least 450 Ma of evolution; these data resolved many of the critical nodes of the diversification of bryophytes. The data also highlight the need to explore the mechanisms underlying the phylogenetic ambiguity at specific nodes. The phylogenomic data provide an expandable framework toward reconstructing a comprehensive phylogeny of this important group of plants.


Asunto(s)
Briófitas , Hepatophyta , Filogenia , Briófitas/genética , Plantas/genética , Hepatophyta/genética
5.
Memory ; 31(1): 47-60, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36107809

RESUMEN

Event boundaries impose structure on how events are stored in long-term memory. Research with young adults has shown that associations within events are stronger than those that cross event boundaries. Recently, this effect was observed in both young and old adults using movie stimuli (Davis, Chemnitz, et al., 2021). Here, we test whether this effect extends to written narratives. Young and old participants read a series of narratives that were interspersed with temporal shifts in the storyline meant to elicit the perception of an event boundary. Later, participants were cued with sentences and were asked to recall the sentence that immediately followed. We expected participants would have worse memory when a cue and correct answer flanked a boundary than when it did not. In Experiment 1, we found that despite older adults' lower performance overall, both age groups had lower accuracy for cues that flanked a boundary, compared to cues that elicited a response from within the same event. Experiment 2 replicated the results from Experiment 1. Our results support past work that did not find age differences in event perception and demonstrate that older and younger adults may store events similarly in long-term memory.


Asunto(s)
Memoria a Largo Plazo , Recuerdo Mental , Adulto Joven , Humanos , Anciano , Memoria a Largo Plazo/fisiología , Recuerdo Mental/fisiología , Señales (Psicología) , Lenguaje , Trastornos de la Memoria , Envejecimiento/fisiología
6.
Public Health ; 224: 32-40, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37708714

RESUMEN

OBJECTIVES: The purpose of this study was to evaluate food insecurity on body mass index (BMI) and diet-related behaviors among college students and whether psychological well-being (PWB) and stress levels mediate this relationship. STUDY DESIGN: This was a cross-sectional study. METHODS: Data from 1439 students from the American College Health Association National College Health Assessment III (Fall 2020) were used. Food security status was evaluated by the USDA Six-Item Short Form. PWB was measured using the Diener Flourishing Scale. Diet-related behaviors included the average servings of fruits, vegetables, and sugar-sweetened beverages consumed per day. Stress was measured by self-reported levels. Regression model analysis evaluated the influence of food security status, PWB, and stress levels on BMI. PWB and stress were also tested as mediators in the relationship between food insecurity and BMI. RESULTS: Among our sample of college students, 44.54% (n = 641) were food insecure, and 55.46% (n = 798) were food secure. Multiple regression analysis showed that higher food insecurity, older age, full-time enrollment status, and fifth-year student status were positively associated with a higher BMI score (P < 0.05). Results from mediation models revealed that PWB, but not stress, mediated the relationship between food security and BMI among Black/African American students. Regarding diet-related behaviors, high stress levels mediated the relationship between food insecurity and sugar-sweetened beverage intake among students. CONCLUSIONS: Food insecurity appears to influence BMI in college students. This relationship seems to be mediated by disrupted PWB and a higher intake of sugar-sweetened beverages due to stress.

7.
BMC Emerg Med ; 23(1): 86, 2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37553630

RESUMEN

BACKGROUND: Critically ill patients have life-threatening conditions requiring immediate vital organ function intervention. But, critical illness in the emergency department (ED) has not been comprehensively described in resource-limited settings. Understanding the characteristics and dynamics of critical illness can help hospitals prepare for and ensure the continuum of care for critically ill patients. This study aimed to describe the pattern and outcomes of critically ill patients at the ED of the National Hospital in Tanzania from 2019 to 2021. METHODOLOGY: This hospital-records-based retrospective cohort study analyzed records of all patients who attended the ED of Muhimbili National Hospital between January 2019 and December 2021. Data extracted from the ED electronic database included clinical and demographic information, diagnoses, and outcome status at the ED. Critical illness in this study was defined as either a severe derangement of one or more vital signs measured at triage or the provision of critical care intervention. Data were analyzed using Stata 17 to examine critical illnesses' burden, characteristics, first-listed diagnosis, and outcomes at the ED. RESULTS: Among the 158,445 patients who visited the ED in the study period, 16,893 (10.7%) were critically ill. The burden of critical illness was 6,346 (10.3%) in 2019, 5,148 (10.9%) in 2020, and 5,400 (11.0%) in 2021. Respiratory (18.8%), cardiovascular (12.6%), infectious diseases (10.2%), and trauma (10.2%) were the leading causes of critical illness. Most (81.6%) of the critically ill patients presenting at the ED were admitted or transferred, of which 11% were admitted to the ICUs and 89% to general wards. Of the critically ill, 4.8% died at the ED. CONCLUSION: More than one in ten patients attending the Tanzanian National Hospital emergency department was critically ill. The number of critically ill patients did not increase during the pandemic. The majority were admitted to general hospital wards, and about one in twenty died at the ED. This study highlights the burden of critical illness faced by hospitals and the need to ensure the availability and quality of emergency and critical care throughout hospitals.


Asunto(s)
Enfermedad Crítica , Enfermedad Crítica/epidemiología , Servicio de Urgencia en Hospital , Tanzanía/epidemiología , Factores de Tiempo , Humanos , Masculino , Femenino , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estaciones del Año
8.
Plant Cell Environ ; 45(6): 1664-1681, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35147232

RESUMEN

Leaf carbon gain optimization in hot environments requires balancing leaf thermoregulation with avoiding excessive water loss via transpiration and hydraulic failure. The tradeoffs between leaf thermoregulation and transpirational water loss can determine the ecological consequences of heat waves that are increasing in frequency and intensity. We evaluated leaf thermoregulation strategies in warm- (>40°C maximum summer temperature) and cool-adapted (<40°C maximum summer temperature) genotypes of the foundation tree species, Populus fremontii, using a common garden near the mid-elevational point of its distribution. We measured leaf temperatures and assessed three modes of leaf thermoregulation: leaf morphology, midday canopy stomatal conductance and stomatal sensitivity to vapour pressure deficit. Data were used to parameterize a leaf energy balance model to estimate contrasts in midday leaf temperature in warm- and cool-adapted genotypes. Warm-adapted genotypes had 39% smaller leaves and 38% higher midday stomatal conductance, reflecting a 3.8°C cooler mean leaf temperature than cool-adapted genotypes. Leaf temperatures modelled over the warmest months were on average 1.1°C cooler in warm- relative to cool-adapted genotypes. Results show that plants adapted to warm environments are predisposed to tightly regulate leaf temperatures during heat waves, potentially at an increased risk of hydraulic failure.


Asunto(s)
Populus , Árboles , Hojas de la Planta/fisiología , Transpiración de Plantas/fisiología , Populus/genética , Árboles/fisiología , Presión de Vapor , Agua
9.
Gynecol Oncol ; 164(3): 473-480, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35000796

RESUMEN

Equality, equity, and parity in the workplace are necessary to optimize patient care across all aspects of medicine. Gender-based inequities remain an obstacle to quality of care, including within the now majority women subspecialty of gynecologic oncology. The results of the 2020 SGO State of the Society Survey prompted this evidence-based review. Evidence related to relevant aspects of the clinical care model by which women with malignancies are cared for is summarized. Recommendations are made that include ways to create work environments where all members of a gynecologic oncology clinical care team, regardless of gender, can thrive. These recommendations aim to improve equality and equity within the specialty and, in doing so, elevate the care that our patients receive.


Asunto(s)
Neoplasias de los Genitales Femeninos , Lugar de Trabajo , Femenino , Neoplasias de los Genitales Femeninos/terapia , Humanos , Masculino , Encuestas y Cuestionarios
10.
Plant Dis ; 106(12): 3100-3108, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35581912

RESUMEN

Controlled environment experiments were conducted to evaluate the effects of temperature on Calonectria pseudonaviculata mycelial growth and the effects of temperature and infection period on boxwood blight severity. In experiment 1, 15 Oregon isolates (representing five genotypes) were grown on potato dextrose agar (PDA) and malt extract agar (MEA) at six temperatures from 5 to 30°C. Growth (culture diameter) was measured after 2 weeks. Optimal growth occurred at 25°C on PDA and 20°C on MEA. Isolates of genotype G1 also grew faster than genotype G2, but only on MEA at 25°C. In experiment 2, Buxus cultivars Green Velvet (GV, more susceptible) and Winter Gem (WG, more resistant) were inoculated and incubated in moist chambers for 9 or 24 h at 22°C (infection period), then moved into growth chambers at 15 or 25°C. After 4 weeks, chamber temperatures were switched, and plants were incubated for 4 more weeks. Disease severity was evaluated weekly. During the first 4 weeks, disease was generally more severe on GV than WG, on plants with a 24-h versus a 9-h infection period, and on plants incubated at 15°C versus 25°C. However, disease was just as severe on WG as GV when the 24-h infection period was followed by incubation at 15°C. After the temperatures were switched, disease increased only on WG that were cooled from 25 to 15°C. Results show that Oregon isolates of C. pseudonaviculata are capable of growing faster and causing more severe disease at temperatures cooler than those reported previously.


Asunto(s)
Buxus , Temperatura , Oregon , Agar , Enfermedades de las Plantas
11.
Plant Dis ; 106(4): 1157-1166, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34784743

RESUMEN

The degree of flooding commonly used to induce disease in Phytophthora root rot studies rarely occurs in container nurseries. Instead, over-irrigation and poor drainage result in plants periodically sitting in shallow pools of water. Rhododendron plants were grown in a noninfested substrate or substrate infested with Phytophthora cinnamomi or P. plurivora to determine whether root rot induced by flooding represents disease that occurs under simulated nursery conditions when plants are in a shallow pool of water (saucers), or are allowed to freely drain and maintained at ∼75% container capacity (CC). Generally P. cinnamomi caused more disease than P. plurivora, and all water treatments were conducive to root rot. In experiment 1, the amount of disease caused by flooding was similar to that in the saucer treatment (75% CC not tested) while in experiment 2, flooding often caused more rapid and severe disease than the saucer or 75% CC treatment. Pathogens differed in their response to water treatments. P. cinnamomi caused more disease in treatments with >90% substrate moisture for either a short (flood) or long duration (saucer), while P. plurivora was less capable of causing disease when soil moisture was maintained >90% than when substrate moisture was maintained at a more moderate level (flood, 75% CC). Our results indicate that it is not necessary to flood plants to induce disease under experimental conditions and that disease induced by flooding can represent disease in container nurseries when containers are in pools of water or maintained at ∼75% CC. In addition, our results suggest that P. cinnamomi is a more aggressive pathogen than P. plurivora in nursery conditions where drainage is poor; however, both species are capable of causing a similar amount of disease under more typical irrigation management.


Asunto(s)
Phytophthora , Rhododendron , Inundaciones , Phytophthora/fisiología , Enfermedades de las Plantas , Plantas
12.
Clin Infect Dis ; 72(Suppl 3): S152-S157, 2021 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-33905475

RESUMEN

Vector control is widely considered an important tool for lymphatic filariasis (LF) elimination but is not usually included in program budgets and has often been secondary to other policy questions in modelling studies. Evidence from the field demonstrates that vector control can have a large impact on program outcomes and even halt transmission entirely, but implementation is expensive. Models of LF have the potential to inform where and when resources should be focused, but often simplify vector dynamics and focus on capturing human prevalence trends, making them comparatively ill-designed for direct analysis of vector control measures. We review the recent modelling literature and present additional results using a well-established model, highlighting areas of agreement between model predictions and field evidence, and discussing the possible determinants of existing disagreements. We conclude that there are likely to be long-term benefits of vector control, both on accelerating programs and preventing resurgence.


Asunto(s)
Filariasis Linfática , Humanos , Prevalencia
13.
Plant Dis ; 105(10): 2970-2974, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33779252

RESUMEN

Inoculum production is an important part of conducting research with soilborne Phytophthora species. One common method is to incubate Phytophthora cultures in nutrient-amended vermiculite. However, inoculum levels often vary among batches of inoculum, even when production methods remain the same, and incubation typically takes ≥6 weeks, increasing risks for delayed experiments if the resulting inoculum level is too low. A more reliable and rapid method is needed for future studies. Experiments were conducted to determine inoculum levels of Phytophthora cinnamomi and Phytophthora plurivora after incubation in V8 juice-amended vermiculite (standard method); evaluate how inoculum viability was affected by air-drying; develop a modified method that takes less time to produce a vermiculite-based inoculum; and evaluate the effect of storage on inoculum viability. Results showed that the standard method produced inoculum levels from 716 to 1,808 colony forming units (CFUs)/g and that drying to <78% moisture content significantly reduced viability. The modified method used 2-week-old Phytophthora cultures to infest vermiculite at 80% moisture content and produced inoculum levels from 214 to 525 CFU/g. Storage for >1 day generally reduced inoculum viability. Although inoculum levels from the modified method were lower than the standard method, inoculum levels for each isolate were more consistent between trials, and the modified method was 6 to 8 weeks faster. Production with the modified method can also be easily scaled up by infesting a greater volume of vermiculite with additional cultures of Phytophthora. These results are important because they help explain variability in soilborne Phytophthora inoculum production and storage and provide a new method for producing inoculum more quickly.


Asunto(s)
Phytophthora , Enfermedades de las Plantas , Suelo
14.
Plant Dis ; 105(9): 2494-2502, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33487014

RESUMEN

Phytophthora root rot is a destructive disease of rhododendron that causes substantial losses of this nursery crop in infested field and container production areas. Historically, Phytophthora cinnamomi was considered the main causal agent of the disease. However, a recent survey of soilborne Phytophthora species from symptomatic rhododendrons in Oregon revealed that P. plurivora is more common than P. cinnamomi, and that several other Phytophthora species may be involved. We investigated the ability of the five most abundant species from the survey to cause root rot: P. plurivora, P. cinnamomi, P. pini, P. pseudocryptogea, and P. cambivora. Three to four isolates were selected for each species from across six Oregon nurseries. Media of containerized Rhododendron catawbiense 'Boursault' was infested with single isolates in a randomized complete block design in a greenhouse. Phytophthora cinnamomi, P. pini, and P. plurivora rapidly caused ≥90% of severe root rot, whereas P. pseudocryptogea caused more moderate disease (46% of severe root rot). Phytophthora cambivora failed to produce enough inoculum and was used at a lower inoculum density than the other four species; however, occasionally, it caused severe root rot (5% incidence). No differences in virulence were observed among isolates of the same species, except for one isolate of P. plurivora that caused less disease than other P. plurivora isolates. This study demonstrates that all five Phytophthora species, which were representative of 94% of the survey isolates, are capable of causing severe root rot and plant death, but that not all species are equally virulent.


Asunto(s)
Phytophthora , Rhododendron , Oregon , Enfermedades de las Plantas , Virulencia
15.
Plant Dis ; 105(5): 1505-1514, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33337240

RESUMEN

Phytophthora root rot, caused by many soilborne Phytophthora spp., is a significant disease affecting the $42 million rhododendron nursery industry. Rhododendron growers have increasingly reported failure by two systemic fungicides, phosphorous acid and mefenoxam, to adequately control root rot. Both fungicides may be applied as a foliar spray or soil drench but it is unknown how application method, fungicide chemistry, or pathogen diversity affects disease control. Therefore, two experiments were conducted to (i) determine whether differences in application method or fungicide chemistry affect control of root rot caused by P. cinnamomi and P. plurivora and (ii) evaluate the sensitivity of Phytophthora spp. and isolates from the rhododendron industry to each fungicide. Results demonstrated that soil drenches of either fungicide were more effective than foliar sprays for control of P. cinnamomi but were ineffective for P. plurivora. Furthermore, Phytophthora spp. and isolates varied in sensitivity to phosphorous acid and mefenoxam, and there were multiple fungicide-insensitive isolates, especially within P. plurivora. Differences in sensitivity were also observed among isolates from different nurseries and production systems, with some nurseries having less sensitive isolates than others and with container systems generally having less sensitive isolates than field systems. Our results provide three potential reasons for why fungicide control of Phytophthora root rot might fail: (i) the fungicide can be applied to the wrong portion of the plant for optimal control, (ii) there are differences in fungicide sensitivity among soilborne Phytophthora spp. and isolates infecting rhododendron, and (iii) fungicide-insensitive isolates are present in the rhododendron nursery industry.


Asunto(s)
Phytophthora , Rhododendron , Alanina/análogos & derivados , Ácidos Fosforosos , Enfermedades de las Plantas
16.
Am J Physiol Lung Cell Mol Physiol ; 319(6): L957-L967, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-32996783

RESUMEN

Electronic nicotine delivery systems, or e-cigarettes, utilize a liquid solution that normally contains propylene glycol (PG) and vegetable glycerin (VG) to generate vapor and act as a carrier for nicotine and flavorings. Evidence indicated these "carriers" reduced growth and survival of epithelial cells including those of the airway. We hypothesized that 3% PG or PG mixed with VG (3% PG/VG, 55:45) inhibited glucose uptake in human airway epithelial cells as a first step to reducing airway cell survival. Exposure of H441 or human bronchiolar epithelial cells (HBECs) to PG and PG/VG (30-60 min) inhibited glucose uptake and mitochondrial ATP synthesis. PG/VG inhibited glycolysis. PG/VG and mannitol reduced cell volume and height of air-liquid interface cultures. Mannitol, but not PG/VG, increased phosphorylation of p38 MAPK. PG/VG reduced transepithelial electrical resistance, which was associated with increased transepithelial solute permeability. PG/VG decreased fluorescence recovery after photobleaching of green fluorescent protein-linked glucose transporters GLUT1 and GLUT10, indicating that glucose transport function was compromised. Puffing PG/VG vapor onto the apical surface of primary HBECs for 10 min to mimic the effect of e-cigarette smoking also reduced glucose transport. In conclusion, short-term exposure to PG/VG, key components of e-cigarettes, decreased glucose transport and metabolism in airway cells. We propose that this was a result of PG/VG reduced cell volume and membrane fluidity, with further consequences on epithelial barrier function. Taking these results together, we suggest these factors contribute to reduced defensive properties of the epithelium. We propose that repeated/chronic exposure to these agents are likely to contribute to airway damage in e-cigarette users.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Células Epiteliales/efectos de los fármacos , Glucosa/metabolismo , Sistema Respiratorio/efectos de los fármacos , Transporte Biológico/efectos de los fármacos , Transporte Biológico/fisiología , Glicerol/farmacología , Humanos , Propilenglicol/farmacología
17.
Pediatr Diabetes ; 21(7): 1277-1284, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32738012

RESUMEN

BACKGROUND: Youth with type 1 diabetes (T1D) are encouraged to participate in physical activity (PA). Studies have identified fear of hypoglycemia (FOH) as a barrier to participating in PA. OBJECTIVES: To examine (a) PA patterns in youth with T1D by age group and (b) the relationship between both parental and youth FOH and youth PA. METHODS: A cross-sectional analysis from the SEARCH cohort study visit of youth ages 10 to 17 years with T1D (n = 1129) was conducted. Linear regression models estimated the association between self-reported number of days of vigorous PA (VPA) and moderate PA (MPA) and both youth- and parent-reported FOH. Multivariable models were adjusted for age, sex, race, duration of T1D, HbA1c, use of continuous glucose monitoring (CGM), recent severe hypoglycemia, primary insulin regimen, and BMI. RESULTS: Participants were 52% female, had mean (sd) age 14.4 (4.2) years, diabetes duration 7.5 years (1.8), HbA1c 9.2% (1.7). Older youth were less likely to engage in VPA (P < .01), or sports teams (P < .01), but more likely to engage in MPA (P < .01). Higher youth FOH (behavior subscale) was associated with increased levels of VPA (ß (se) 0.30 (0.11), P = .01) but not significantly associated with MPA (P = .06). There was no statistically significant association between parental FOH and youth PA. CONCLUSIONS: In SEARCH participants with T1D, VPA, and team sports participation declined with age, while MPA increased. We observed that higher scores on the youth FOH behavioral subscale were associated with increased VPA levels, suggesting that FOH may be less of a barrier to PA than previously thought.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/psicología , Ejercicio Físico/psicología , Miedo , Hipoglucemia/etiología , Hipoglucemia/psicología , Adolescente , Automonitorización de la Glucosa Sanguínea , Niño , Estudios de Cohortes , Estudios Transversales , Diabetes Mellitus Tipo 1/terapia , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Masculino , Padres/psicología
18.
J Dairy Sci ; 103(12): 11876-11888, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33069401

RESUMEN

The objectives of this study were (1) to characterize Ca levels and polymorphonuclear leukocyte (PMN) function in primiparous and multiparous animals following oral Ca bolus supplementation, and (2) to determine differential responses of boluses containing a lower dose of Ca than traditionally used in primiparous animals on Ca levels and PMN function. Jersey × Holstein crossbred animals (n = 104) were enrolled within 24 h of parturition. All animals were blocked by time relative to calving and randomly assigned to treatment. The Ca boluses were composed of a mixture of Ca chloride, Ca sulfate, and Ca propionate. For objective 1, animals were assigned to control (CON; no Ca supplementation), or a series of 2 Ca boluses given 24 h apart for a total of 50 g of Ca. Objective 2 treatments included control (CON; no Ca supplementation), a series of 2 Ca boluses given 24 h apart containing 50 g of Ca, or a series of 2 Ca boluses given 24 h apart containing 25 g of Ca. Blood samples were collected on d 1 (<24 h), 2, 3, 5, and 7 relative to parturition. Total serum Ca, serum haptoglobin, PMN intracellular Ca, PMN intracellular Ca after stimulation with an environmental Escherichia coli, PMN L-selectin surface expression, and PMN phagocytic and oxidative burst activities were analyzed. For objective 1 a tendency was detected for a treatment difference on basal intracellular PMN Ca and a treatment difference on E. coli-stimulated intracellular PMN Ca. We detected a parity × DIM effect for PMN oxidative burst intensity. However, no other interactions or parity effects on other functional PMN variables were detectable. In primiparous animals, we found a treatment difference for E. coli-stimulated intracellular PMN Ca among animals given 50 g of Ca but no treatment difference on basal intracellular PMN Ca. The 50 g of Ca treatment increased both PMN phagocytosis and oxidative burst intensities. Supplementing animals with 50 g of oral Ca increased intracellular PMN Ca and influenced PMN function.


Asunto(s)
Calcio/administración & dosificación , Bovinos/fisiología , Suplementos Dietéticos/análisis , Administración Oral , Animales , Calcio/sangre , Escherichia coli/fisiología , Femenino , Espacio Intracelular/metabolismo , Lactancia , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Paridad , Parto , Embarazo , Estallido Respiratorio/efectos de los fármacos
19.
Plant Dis ; 104(6): 1841-1850, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32370604

RESUMEN

Rhododendron root rot is a severe disease that causes significant mortality in rhododendrons. Information is needed about the incidence and identity of soilborne Phytophthora and Pythium species causing root rot in Pacific Northwest nurseries in order to better understand the disease etiology and to optimize disease control strategies. The last survey focusing solely on soilborne oomycete pathogens in rhododendron production was conducted in 1974. Since then, advances in pathogen identification have occurred, new species may have been introduced, pathogen communities may have shifted, and little is known about Pythium species affecting this crop. Therefore, a survey of root-infecting Phytophthora and Pythium species was conducted at seven nurseries from 2013 to 2017 to (i) document the incidence of root rot damage at each nursery and stage of production, (ii) identify soilborne oomycetes infecting rhododendron, and (iii) determine whether there are differences in pathogen diversity among nurseries and production systems. Rhododendrons from propagation, container, and field systems were sampled and Phytophthora and Pythium species were isolated from the roots and collar region. Root rot was rarely evident in propagation systems, which were dominated by Pythium species. However, severe root rot was much more common in container and field systems where the genus Phytophthora was also more prevalent, suggesting that Phytophthora species are the primary cause of severe root rot and that most contamination by these pathogens comes in after the propagation stage. In total, 20 Pythium species and 11 Phytophthora species were identified. Pythium cryptoirregulare, Pythium aff. macrosporum, Phytophthora plurivora, and Phytophthora cinnamomi were the most frequently isolated species and the results showed that Phytophthora plurivora has become much more common than in the past. Phytophthora diversity was also greater in field systems than in propagation or container systems. Risks for Phytophthora contamination were commonly observed during the survey and included placement of potting media in direct contact with field soil, the presence of dead plants that could serve as continuous sources of inoculum, and the presence of excess water as a result of poor drainage, overirrigation, or malfunctioning irrigation equipment. In the past, research on disease development and root rot disease control in rhododendron focused almost exclusively on Phytophthora cinnamomi. More research is needed on both of these topics for the other root-infecting species identified in this survey.


Asunto(s)
Phytophthora , Pythium , Rhododendron , Noroeste de Estados Unidos , Enfermedades de las Plantas
20.
Diabet Med ; 36(10): 1294-1303, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30972800

RESUMEN

AIMS: To examine the effect of pump vs injection therapy on the lipid profile of children with Type 1 diabetes mellitus. METHODS: A cross-sectional analysis of the lipid profile of children aged ≤ 18 years with Type 1 diabetes mellitus from SWEET, an international diabetes registry, was conducted with a focus on the effect of treatment regimen. Dyslipidaemia was defined as LDL cholesterol ≥2.6 mmol/l or non-HDL cholesterol ≥3.1 mmol/l. LDL and non-HDL cholesterol values among 14 290 children (52% boys, 51% receiving pump therapy) from 60 SWEET centres were analysed by linear and logistic regression analysis adjusted for sex, age, diabetes duration, HbA1c and BMI-standard deviation score group, region, and common interactions between age, sex, HbA1c and BMI. RESULTS: This study confirmed the established associations of increased lipids with female sex, age, diabetes duration, HbA1c and BMI. LDL and non-HDL cholesterol levels were lower in the pump therapy group compared to the injection therapy group [LDL cholesterol: injection therapy 2.44 mmol/l (95% CI 2.42 to 2.46) vs pump therapy 2.39 mmol/l (95% CI 2.37-2.41), P<0.001; non-HDL cholesterol: injection therapy 2.88 mmol/l (95% CI 2.86 to 2.90) vs pump therapy 2.80 mmol/l (95% CI 2.78-2.82), both P<0.0001]. Similarly, the odds ratios for LDL cholesterol ≥2.6 mmol/l [0.89 (95% CI 0.82-0.97)] and non-HDL cholesterol ≥3.1 mmol/l [0.85 (0.78 to 0.93)] were significantly lower in the pump therapy group, even after all adjustments. CONCLUSIONS: Our results indicate that pump therapy is associated with a better lipid profile.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Lípidos/sangre , Adolescente , Glucemia/análisis , Peso Corporal , Niño , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Estudios de Cohortes , Bases de Datos Factuales , Diabetes Mellitus Tipo 1/complicaciones , Dislipidemias/epidemiología , Femenino , Humanos , Inyecciones , Insulina/administración & dosificación , Sistemas de Infusión de Insulina , Masculino , Sistema de Registros , Factores Sexuales
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