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1.
Proc Natl Acad Sci U S A ; 118(22)2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34050025

RESUMEN

Urgent action is needed to prevent the demise of coral reefs as the climate crisis leads to an increasingly warmer and more acidic ocean. Propagating climate change-resistant corals to restore degraded reefs is one promising strategy; however, empirical evidence is needed to determine whether stress resistance is affected by transplantation beyond a coral's native reef. Here, we assessed the performance of bleaching-resistant individuals of two coral species following reciprocal transplantation between reefs with distinct pH, salinity, dissolved oxygen, sedimentation, and flow dynamics to determine whether heat stress response is altered following coral exposure to novel physicochemical conditions in situ. Critically, transplantation had no influence on coral heat stress responses, indicating that this trait was relatively fixed. In contrast, growth was highly plastic, and native performance was not predictive of performance in the novel environment. Coral metabolic rates and overall fitness were higher at the reef with higher flow, salinity, sedimentation, and diel fluctuations of pH and dissolved oxygen, and did not differ between native and cross-transplanted corals, indicating acclimatization via plasticity within just 3 mo. Conversely, cross-transplants at the second reef had higher fitness than native corals, thus increasing the fitness potential of the recipient population. This experiment was conducted during a nonbleaching year, so the potential benefits to recipient population fitness are likely enhanced during bleaching years. In summary, this study demonstrates that outplanting bleaching-resistant corals is a promising tool for elevating the resistance of coral populations to ocean warming.


Asunto(s)
Aclimatación , Cambio Climático , Arrecifes de Coral , Animales , Antozoos/fisiología , Respuesta al Choque Térmico
2.
Hosp Pediatr ; 12(12): 1093-1100, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36321385

RESUMEN

BACKGROUND: Red reflex is a routine part of newborn examination in most high-income countries. It is an inexpensive, noninvasive method of detecting serious ocular abnormalities like cataracts, retinoblastoma, vitreous masses, etc. The American Academy of Pediatrics recommends red reflex examination before discharge from newborn nursery. However, the current rate of red reflex examination in the NICUs in the United States is unknown. We noted a low rate of documentation (19%) in our level III NICU, prompting us to initiate this quality improvement project to improve this rate. METHODS: We created a key-driver diagram and summarized possible interventions to achieve our aim to increase the documentation rate to >80%. We implemented various interventions over 4 plan-do-study-act cycles. Over 19 months, we educated the nurses and the providers regarding the importance of red reflex assessment, placed visual reminders to check red reflex, implemented discharge checklist for the residents, and improved the accessibility to ophthalmoscope. RESULTS: Infants discharged from our NICU during a 25-month period included 1168 infants who an ophthalmologist did not formally examine. The rate of red reflex documentation improved significantly from a baseline of 19% (6 months before the first plan-do-study-act cycle) to 89.5% (during the 19-month intervention period). One abnormal red reflex was detected during this study. CONCLUSIONS: Implementation of this project has led to a culture change at our institution, which will help prevent us from missing the diagnosis of serious visual abnormalities in the future.


Asunto(s)
Unidades de Cuidado Intensivo Neonatal , Mejoramiento de la Calidad , Recién Nacido , Lactante , Humanos , Niño , Alta del Paciente , Documentación , Reflejo
3.
Phytopathology ; 101(4): 492-501, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21391827

RESUMEN

The transmission ecology of Phytophthora ramorum from bay laurel (Umbellularia californica) leaves was compared between mixed-evergreen and redwood forest types throughout winter and summer disease cycles in central, coastal California. In a preliminary multisite study, we found that abscission rates of infected leaves were higher at mixed-evergreen sites. In addition, final infection counts were slightly higher at mixed-evergreen sites or not significantly different than at redwood sites, in part due to competition from other foliar pathogens at redwood sites. In a subsequent, detailed study of paired sites where P. ramorum was the main foliar pathogen, summer survival of P. ramorum in bay laurel leaves was lower in mixed-evergreen forest due to lower recovery from infected attached leaves and higher abscission rates of infected leaves. Onset of inoculum production and new infections of bay laurel leaves occurred later in mixed-evergreen forest. Mean inoculum levels in rainwater and final infection counts on leaves were higher in redwood forest. Based on these two studies, lower summer survival of reservoir inoculum in bay laurel leaves in mixed-evergreen forest may result in delayed onset of both inoculum production and new infections, leading to slower disease progress in the early rainy season compared with redwood forest. Although final infection counts also will depend on other foliar pathogens and disease history, in sites where P. ramorum is the main foliar pathogen, these transmission patterns suggest higher rates of disease spread in redwood forests during rainy seasons of short or average length.


Asunto(s)
Phytophthora/patogenicidad , Enfermedades de las Plantas/microbiología , Hojas de la Planta/microbiología , Árboles/clasificación , Umbellularia/microbiología , California , Supervivencia Celular , Interacciones Huésped-Patógeno , Modelos Lineales , Phytophthora/aislamiento & purificación , Quercus , Estaciones del Año , Sequoia/microbiología , Factores de Tiempo , Tracheophyta , Árboles/microbiología
4.
Sci Rep ; 11(1): 11690, 2021 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-34083688

RESUMEN

Literature supports an association between transfusions and gut injury in preterm infants. We hypothesized that packed red blood (PRBC) transfusions are associated with kidney inflammation marked by a rise in urinary levels of Kidney Injury Molecule 1 (KIM-1). Prospectively, KIM-1 levels were measured before and then at 6, 12 and 24 h after a PRBC transfusion. Results are presented as mean (± SD) and median (IQR). Thirty-four infants, birth weight 865 (± 375) g, had higher pretransfusion KIM-1 levels of 2270 (830, 3250) pg/mg than what is normal for age. These were not associated with hematocrit levels. KIM-1 levels peaked between 6 and 12 h after the transfusion. Levels peaked to 3300 (1990, 6830) pg/mg; levels returned to pretransfusion levels of 2240 (1240, 3870) pg/mg by 24 h, p < 0.01. The 24-h post-transfusion KIM-1 levels were similar to pretransfusion levels, p = 0.63. PRBC transfusions in preterm infants are associated with an elevation in urinary KIM-1 levels. The mechanism of this association may be important in studying transfusion associated organ injury. KIM-1, as an inflammatory marker, may be helpful in assessing the effect of different transfusion volumes or in evaluating operational thresholds of anemia in premature infants.


Asunto(s)
Receptor Celular 1 del Virus de la Hepatitis A/metabolismo , Anemia/terapia , Anemia/orina , Peso al Nacer/fisiología , Transfusión Sanguínea/métodos , Femenino , Humanos , Lactante , Recién Nacido de Bajo Peso , Recién Nacido , Recien Nacido Prematuro , Masculino , Estudios Prospectivos
5.
Sci Rep ; 10(1): 13664, 2020 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-32788607

RESUMEN

The persistence of reef building corals is threatened by human-induced environmental change. Maintaining coral reefs into the future requires not only the survival of adults, but also the influx of recruits to promote genetic diversity and retain cover following adult mortality. Few studies examine the linkages among multiple life stages of corals, despite a growing knowledge of carryover effects in other systems. We provide a novel test of coral parental conditioning to ocean acidification (OA) and tracking of offspring for 6 months post-release to better understand parental or developmental priming impacts on the processes of offspring recruitment and growth. Coral planulation was tracked for 3 months following adult exposure to high pCO2 and offspring from the second month were reciprocally exposed to ambient and high pCO2 for an additional 6 months. Offspring of parents exposed to high pCO2 had greater settlement and survivorship immediately following release, retained survivorship benefits during 1 and 6 months of continued exposure, and further displayed growth benefits to at least 1 month post release. Enhanced performance of offspring from parents exposed to high conditions was maintained despite the survivorship in both treatments declining in continued exposure to OA. Conditioning of the adults while they brood their larvae, or developmental acclimation of the larvae inside the adult polyps, may provide a form of hormetic conditioning, or environmental priming that elicits stimulatory effects. Defining mechanisms of positive acclimatization, with potential implications for carry over effects, cross-generational plasticity, and multi-generational plasticity, is critical to better understanding ecological and evolutionary dynamics of corals under regimes of increasing environmental disturbance. Considering environmentally-induced parental or developmental legacies in ecological and evolutionary projections may better account for coral reef response to the chronic stress regimes characteristic of climate change.


Asunto(s)
Adaptación Fisiológica , Antozoos/crecimiento & desarrollo , Ecología , Ambiente , Larva/crecimiento & desarrollo , Animales , Dióxido de Carbono/análisis , Cambio Climático , Concentración de Iones de Hidrógeno , Agua de Mar/química
6.
Phytopathology ; 99(7): 792-5, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19522576

RESUMEN

Phytophthora ramorum, the causal agent of sudden oak death and ramorum blight, is known to exist as three distinct clonal lineages which can only be distinguished by performing molecular marker-based analyses. However, in the recent literature there exists no consensus on naming of these lineages. Here we propose a system for naming clonal lineages of P. ramorum based on a consensus established by the P. ramorum research community. Clonal lineages are named with a two letter identifier for the continent on which they were first found (e.g., NA = North America; EU = Europe) followed by a number indicating order of appearance. Clonal lineages known to date are designated NA1 (mating type: A2; distribution: North America; environment: forest and nurseries), NA2 (A2; North America; nurseries), and EU1 (predominantly A1, rarely A2; Europe and North America; nurseries and gardens). It is expected that novel lineages or new variants within the existing three clonal lineages could in time emerge.


Asunto(s)
Filogenia , Phytophthora/clasificación , Phytophthora/citología , Enfermedades de las Plantas/microbiología , Quercus/microbiología , Terminología como Asunto , Células Clonales , Genotipo , Geografía , Phytophthora/genética , Phytophthora/aislamiento & purificación
7.
Evol Appl ; 9(9): 1165-1178, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27695524

RESUMEN

As climate change challenges organismal fitness by creating a phenotype-environment mismatch, phenotypic plasticity generated by epigenetic mechanisms (e.g., DNA methylation) can provide a temporal buffer for genetic adaptation. Epigenetic mechanisms may be crucial for sessile benthic marine organisms, such as reef-building corals, where ocean acidification (OA) and warming reflect in strong negative responses. We tested the potential for scleractinian corals to exhibit phenotypic plasticity associated with a change in DNA methylation in response to OA. Clonal coral fragments of the environmentally sensitive Pocillopora damicornis and more environmentally robust Montipora capitata were exposed to fluctuating ambient pH (7.9-7.65) and low pH (7.6-7.35) conditions in common garden tanks for ~6 weeks. M. capitata responded weakly, or acclimated more quickly, to OA, with no difference in calcification, minimal separation of metabolomic profiles, and no change in DNA methylation between treatments. Conversely, P. damicornis exhibited diminished calcification at low pH, stronger separation in metabolomic profiles, and responsiveness of DNA methylation to treatment. Our data suggest corals differ in their temporal dynamics and sensitivity for environmentally triggered real-time epigenetic reprogramming. The generation of potentially heritable plasticity via environmental induction of DNA methylation provides an avenue for assisted evolution applications in corals under rapid climate change.

8.
Phytopathology ; 95(5): 587-96, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-18943326

RESUMEN

ABSTRACT During 2001 to 2003, the transmission biology of Phytophthora ramorum, the causal agent of sudden oak death, was studied in mixedevergreen forest, a common forest type in northern, coastal California. Investigation of the sources of spore production focused on coast live oak (Quercus agrifolia) and bay laurel (Umbellularia californica), dominant hosts that comprised 39.7 and 46.2% of the individuals at the study site, respectively. All tests for inoculum production from the surface of infected coast live oak bark or exudates from cankers were negative. In contrast, sporangia and chlamydospores were produced on the surface of infected bay laurel leaves. Mean number of zoospores produced from infected bay laurel leaves under natural field conditions during rainstorms was 1,173.0 +/- SE 301.48, and ranged as high as 5,200 spores/leaf. P. ramorum was recovered from rainwater, soil, litter, and streamwater during the mid- to late rainy season in all 3 years of the study. P. ramorum was not recovered from sporadic summer rains or soil and litter during the hot, dry summer months. Concentrations of inoculum in rainwater varied significantly from year to year and increased as the rainy season progressed for the two complete seasons that were studied. Potential dispersal distances were investigated for rainwater, soil, and streamwater. In rainwater, inoculum moved 5 and 10 m from the inoculum source. For soil, transmission of inoculum was demonstrated from infested soil to bay laurel green leaf litter, and from bay laurel green leaf litter to aerial leaves of bay laurel seedlings. One-third to one-half of the hikers tested at the study site during the rainy season also were carrying infested soil on their shoes. In streamwater, P. ramorum was recovered from an unforested site in pasture 1 km downstream of forest with inoculum sources. In total, these studies provide details on the production and spread of P. ramorum inoculum in mixed-evergreen forest to aid forecasting and managing disease transmission of this environmentally destructive pathogen.

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