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1.
Proc Natl Acad Sci U S A ; 116(52): 26382-26388, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31818944

RESUMEN

The glaciers near Puncak Jaya in Papua, Indonesia, the highest peak between the Himalayas and the Andes, are the last remaining tropical glaciers in the West Pacific Warm Pool (WPWP). Here, we report the recent, rapid retreat of the glaciers near Puncak Jaya by quantifying the loss of ice coverage and reduction of ice thickness over the last 8 y. Photographs and measurements of a 30-m accumulation stake anchored to bedrock on the summit of one of these glaciers document a rapid pace in the loss of ice cover and a ∼5.4-fold increase in the thinning rate, which was augmented by the strong 2015-2016 El Niño. At the current rate of ice loss, these glaciers will likely disappear within the next decade. To further understand the mechanisms driving the observed retreat of these glaciers, 2 ∼32-m-long ice cores to bedrock recovered in mid-2010 are used to reconstruct the tropical Pacific climate variability over approximately the past half-century on a quasi-interannual timescale. The ice core oxygen isotopic ratios show a significant positive linear trend since 1964 CE (0.018 ± 0.008‰ per year; P < 0.03) and also suggest that the glaciers' retreat is augmented by El Niño-Southern Oscillation processes, such as convection and warming of the atmosphere and sea surface. These Papua glaciers provide the only tropical records of ice core-derived climate variability for the WPWP.

2.
Teach Learn Med ; 34(3): 329-340, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34011226

RESUMEN

Issue: As U.S. healthcare systems plan for future physician workforce needs, the systemic impacts of climate change, a worldwide environmental and health crisis, have not been factored in. The current focus on increasing the number of trained physicians and optimizing efficiencies in healthcare delivery may be insufficient. Graduate medical education (GME) priorities and training should be considered in order to prepare a climate-educated physician workforce. Evidence: We used a holistic lens to explore the available literature regarding the intersection of future physician workforce needs, GME program priorities, and resident education within the larger context of climate change. Our interinstitutional, transdisciplinary team brought perspectives from their own fields, including climate science, climate and health research, and medical education to provide recommendations for building a climate-educated physician workforce. Implications: Acknowledging and preparing for the effects of climate change on the physician workforce will require identification of workforce gaps, changes to GME program priorities, and education of trainees on the health and societal impacts of climate change. Alignment of GME training with workforce considerations and climate action and adaptation initiatives will be critical in ensuring the U.S. has a climate-educated physician workforce capable of addressing health and healthcare system challenges. This article offers a number of recommendations for physician workforce priorities, resident education, and system-level changes to better prepare for the health and health system impacts of climate change.


Asunto(s)
Internado y Residencia , Medicina , Médicos , Cambio Climático , Educación de Postgrado en Medicina , Humanos , Estados Unidos , Recursos Humanos
3.
Arthroscopy ; 37(7): 2318-2333.e3, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33621647

RESUMEN

PURPOSE: To appraise the available animal and human studies investigating low-intensity pulsed ultrasound stimulation (LIPUS) on tendon, ligament, and bone-soft tissue (B-ST) junction healing. METHODS: A systematic review of PUBMED, EMBASE, and the Cochrane Library was performed for animal and human studies investigating the effects of LIPUS on tendon, ligament, and B-ST junction healing. The systematic search was performed using the key term "low intensity pulsed ultrasound" and any of the following: "tendon," "ligament," "tendon-bone," and "bone-tendon." Inclusion criteria consisted of (1) randomized controlled trials assessing the effect of LIPUS on bone, tendon, and soft tissue in animals or humans and (2) English-language articles. RESULTS: A total of 28 animal and 2 human studies met inclusion criteria. Animal studies utilized various models, including Achilles and patellar tendon transections, medial collateral ligament transections, and surgical repair of patellar tendon, rotator cuff tendon, and anterior cruciate ligament, to evaluate the effects of LIPUS. Animal studies demonstrated significantly improved collagen content and organization, bone formation, fibrocartilage remodeling, and mechanical strength with LIPUS treatment compared with controls. In human trials, LIPUS treatment of chronic tendinopathies did not improve clinical outcomes. CONCLUSIONS: In acute injury animal models, LIPUS augmented healing of acute tendon, ligament, and B-ST junction injuries through increased collagen content and organization; increased anti-inflammatory cellular signaling; and increased angiogenesis. However, in 2 human studies investigating chronic tendinopathy, LIPUS did not lead to superior outcomes compared with controls. CLINICAL RELEVANCE: Animal models suggest that LIPUS may be a promising noninvasive treatment modality for accelerating patient recovery after acute tendon and ligament injuries, as well as after surgical repair of B-ST junction injuries, but this has not been demonstrated in human studies. Randomized clinical trials evaluating LIPUS for acute tendon and ligament injuries are warranted.


Asunto(s)
Tendón Calcáneo , Ligamento Rotuliano , Tendinopatía , Terapia por Ultrasonido , Animales , Humanos , Tendinopatía/terapia , Ondas Ultrasónicas
4.
Environ Monit Assess ; 189(12): 649, 2017 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-29178008

RESUMEN

The objective of this research is to characterize the variability of trace metals in the Rio Santa watershed based on synoptic sampling applied at a large scale. To that end, we propose a combination of methods based on the collection of water, suspended sediments, and riverbed sediments at different points of the watershed within a very limited period. Forty points within the Rio Santa watershed were sampled between June 21 and July 8, 2013. Forty water samples, 36 suspended sediments, and 34 riverbed sediments were analyzed for seven trace metals. The results, which were normalized using the USEPA guideline for water and sediments, show that the Rio Santa water exhibits Mn concentrations higher than the guideline at more than 50% of the sampling points. As is the second highest contaminating element in the water, with approximately 10% of the samples containing concentrations above the guideline. Sediments collected in the Rio Santa riverbed were heavily contaminated by at least four of the tested elements at nearly 85% of the sample points, with As presenting the highest normalized concentration, at more than ten times the guideline. As, Cd, Fe, Pb, and Zn present similar concentration trends in the sediment all along the Rio Santa.The findings indicate that care should be taken in using the Rio Santa water and sediments for purposes that could affect the health of humans or the ecosystem. The situation is worse in some tributaries in the southern part of the watershed that host both active and abandoned mines and ore-processing plants.


Asunto(s)
Sedimentos Geológicos/química , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Ecosistema , Monitoreo del Ambiente/métodos , Cubierta de Hielo , Minería , Perú
5.
Clin Orthop Relat Res ; 474(1): 237-43, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26394639

RESUMEN

BACKGROUND: Despite being recognized as the gold standard in isolated clubfoot treatment, the Ponseti casting method has yielded variable results. Few studies have directly compared common predictors of treatment failure between institutions with high versus low failure rates. QUESTIONS/PURPOSES: We asked: (1) is the provider's rigid adherence to the Ponseti method associated with a lower likelihood of unplanned clubfoot surgery, and (2) at the institution that did not adhere rigidly to Ponseti's principles, are any demographic or treatment-related factors associated with increased likelihood of unplanned clubfoot surgery? METHODS: After institutional review board approval, a consecutive series of patients with a diagnosis of isolated clubfoot who underwent treatment between January 2003 and December 2007 were identified. At Institution 1, 91 of 133 patients met the eligibility criteria and were followed for a minimum of 2 years compared with 58 of 58 patients at Institution 2. At Institution 1, 16 providers managed care using a conservative casting approach based on the Ponseti method. However, treatment was adapted by the provider(s). At Institution 2, one orthopaedic surgeon managed care with strict adherence to the Ponseti method. Surgical indications at both institutions included the presence of a persistent equinovarus foot position while standing. A chart review was used to collect data related to proportion of patients undergoing unplanned additional treatment for deformity recurrences after Ponseti casting, demographics, and treatment patterns. RESULTS: The proportion of subjects who underwent unplanned major surgical intervention was greater (odds ratio [OR], 51.1; 95% CI, 6.8-384.0; p < 0.001) at Institution 1 (60 of 131, 47%) compared with Institution 2 (two of 91, 2%). There was no difference (p = 0.200) in the proportion of patients who underwent additional casting, repeat tendo Achilles lengthening, and/or anterior tibialis tendon transfer only (minor recurrence) at Institution 1 (nine of 131, 7%) compared with Institution 2 (11 of 91, 13%). At Institution 1, an increase in the number of revision casts (multiple vs no casts, hazard ratio [HR] = 3.9; 95% CI, 2.0-7.6; p < 0.001) and an increase in the number of cast-related complications (multiple vs no complications, HR = 2.8; 95% CI, 1.2-6.7; p = 0.019) were associated with increased risk of major surgery in the multivariate analysis. CONCLUSIONS: Rigid commitment to the Ponseti method in the conservative treatment of patients with isolated clubfoot was associated with a lower risk of subsequent unplanned surgical intervention. In addition, clubfoot treatment programs that use a care model that prioritizes continuity in care and dedication to the Ponseti method may decrease the proportion of patients who undergo unplanned surgical intervention. LEVEL OF EVIDENCE: Level III, therapeutic study.


Asunto(s)
Moldes Quirúrgicos , Pie Equinovaro/terapia , Adhesión a Directriz/normas , Procedimientos Ortopédicos/instrumentación , Pautas de la Práctica en Medicina/normas , Pie Equinovaro/diagnóstico , Pie Equinovaro/cirugía , Colorado , Femenino , Humanos , Modelos Logísticos , Masculino , Registros Médicos , Missouri , Oportunidad Relativa , Procedimientos Ortopédicos/efectos adversos , Procedimientos Ortopédicos/métodos , Guías de Práctica Clínica como Asunto/normas , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Insuficiencia del Tratamiento
6.
Plants (Basel) ; 13(10)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38794410

RESUMEN

Root biomass and distribution are influenced by abiotic factors, such as topography and soil physicochemical properties, determining belowground productivity. Hence, we investigated the variation in root biomass and vertical root distribution based on the topography, soil physicochemical properties, and tree influence index, and their relationships, across soil depths (0-10 cm, 10-20 cm, and 20-30 cm) and topographical gradients in a warm-temperate forest in Mt. Duryun, Republic of Korea. Two contrasting research sites were established: a lower slope oriented at ≤3° and an upper slope with a slope of 30°. Each site comprised eleven 400 m2 sampling plots from which root samples from various diameter classes (<2 mm, 2-5 mm, 5-10 mm, and >10 mm) were collected. While the bulk density increased with soil depth in the lower slope, the organic matter, available phosphorus, Ca2+, and Mg2+ showed a reversed pattern. Linear mixed-effects models generally revealed significant negative correlations between root biomass and soil pH, total nitrogen, and cation exchange capacity, particularly in small roots (ßstd = -1.03 to -1.51) and coarse roots (ßstd = -6.30). Root biomass exhibited a 10-15% increase in the upper slope compared to the lower slope, particularly in fine (median = 52.0 g m2-65.64 g m2) and medium roots (median = 56.04 g m2-69.52 g m2) at a 0-20 cm soil depth. While no significant correlation between root biomass and the tree influence index was found on the lower slope, a different pattern was found on the upper slope. Our results indicate that the variation in root biomass and distribution can also be explained by the differences in the soil environment and topographical positions.

7.
Sci Total Environ ; 948: 174750, 2024 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-39009153

RESUMEN

Blue and Green Infrastructures (BGIs) are natural or semi-natural systems that are considered an efficient solution to enhance stormwater management. To assess the performance of BGIs in mitigating floods and droughts in an urban area, a water balance model was developed in this study to simulate runoff formation and propagation. The developed model features fine spatial and temporal resolutions and flexibly integrates BGIs. Combining the conceptual single reservoir approach and the empirical continuous Soil Conservation Service Curve Number (SCS-CN) method, the model achieves computational efficiency, enabling long-term simulations that capture both short-term extreme events and long-term water balance. Its high transferability allows for easy incorporation of local datasets, making it adaptable to various urban contexts. Applied on a university campus located in Belgium, the model was used to simulate the water balance components of feasible BGIs for the study area, which were green roofs, permeable surfaces and rainwater tanks. Scenario analysis of both single BGI and combined BGI implementations was conducted, and all BGI scenarios were evaluated based on peak flow and runoff volume reduction and water balance analysis. Results demonstrate that the implementation of a combination of several BGIs with different functions is an effective solution for both flood control and drought mitigation, as these solutions can significantly reduce runoff flows, increase infiltration and provide considerable rainwater reuse.

8.
Science ; 385(6708): 517-521, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39088605

RESUMEN

Tropical glaciers have retreated over recent decades, but whether the magnitude of this retreat exceeds the bounds of Holocene fluctuations is unclear. We measured cosmogenic beryllium-10 and carbon-14 concentrations in recently exposed bedrock at the margin of four glaciers spanning the tropical Andes to reconstruct their past extents relative to today. Nuclide concentrations are near zero in almost all samples, suggesting that these locations were never exposed during the Holocene. Our data imply that many glaciers in the tropics are probably now smaller than they have been in at least 11,700 years, making the tropics the first large region where this milestone has been documented.

9.
Plants (Basel) ; 13(2)2024 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-38256718

RESUMEN

Urbanization and associated forest conversions have given rise to a continuum of native (forest fragments) and modified (artificial grasslands and perennial ecosystems) land-use types. However, little is known about how these shifts affect soil and fine-root compartments that are critical to a functioning carbon and nutrient circulation system. In this study, soil physicochemical properties, fine-root mass, and vertical distribution patterns were investigated in four representative urban land-use types: grassland (ZJ), perennial agroecosystem (MP), broadleaf deciduous forest patch (QA), and coniferous evergreen forest patch (PD). We quantified the fine-root mass in the upper 30 cm vertical profile (0-30 cm) and at every 5 cm depth across three diameter classes (<2 mm, 2-5 mm, and <5 mm). Soil physicochemical properties, except for phosphorus, nitrogen, ammonium nitrogen, and sodium cations, varied significantly across land-use types. The total root biomass (<5 mm) decreased in the order of QA (700.3 g m-2) > PD (487.2 g m-2) > ZJ (440.1 g m-2) > MP (98.3 g m-2). The fine-root mass of ZJ and MP was correlated with soil nutrients, which was attributed to intensive management operations, while the fine-root mass of QA and PD had a significant relationship with soil organic matter due to the high inputs from forest litter. Very fine roots (<2 mm) presented a distinct decremental pattern with depth for all land-use types, except for MP. Very fine roots populated the topmost 5 cm layer in ZJ, QA, and PD at 52.1%, 49.4%, and 39.4%, respectively. Maintaining a woody fine-root system benefits urban landscapes by promoting soil stabilization, improving ground infiltration rates, and increasing carbon sequestration capacity. Our findings underscore the importance of profiling fine-root mass when assessing urban expansion effects on terrestrial ecosystems.

10.
J Hip Preserv Surg ; 8(1): 51-57, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34567600

RESUMEN

The purpose of this study was to compare measurements of anterior wall index (AWI) and posterior wall index (PWI) on computed tomography (CT) to those on radiographs (XR). A consecutive cohort of 33 patients (45 hips total) being evaluated for hip pain with both XR and CT was examined. Preoperative measurements of AWI and PWI were performed utilizing supine anteroposterior pelvic XR and coronal and swiss axial CT scans by two independent raters. Mean differences between XR and CT measurements were compared, and agreement between measurements was assessed using the concordance correlation coefficient (rc ) and Bland-Altman analysis. A total of 39 hips in 28 patients were analyzed. The mean patient age was 31.1 ± 9.0 years, and 50% were female. Mean AWI and PWI on XR was 0.50 ± 0.14 and 0.91 ± 0.12, respectively. Measured values of AWI were consistently larger (0.08 ± 0.10, P < 0.01) on XR compared with both coronal and swiss axial CT, with moderate agreement between XR and CT measurements (rc = 0.68-0.70). Measured values of PWI were consistently smaller (0.15 ± 0.12, P < 0.05) on XR compared with both coronal and swiss axial CT, with poor agreement between XR and CT measurements (rc = 0.37-0.45). Measured values of acetabular wall indices on XR were consistently larger for AWI and smaller for PWI relative to CT. Agreement between XR and CT measures of the indices were moderate to poor. This highlights the need for standardization of XR- and CT-based measurements to improve assessment of acetabular coverage and subsequent clinical decision-making.

11.
JBJS Case Connect ; 10(3): e20.00124, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32910579

RESUMEN

CASE: A 65-year-old woman presented with a malaligned, shortened supracondylar distal femoral nonunion. An acute medial closing wedge osteotomy was performed through the nonunion and compressed with a retrograde magnetically controlled intramedullary nail. Osteogenesis with sequential compression and then distraction was performed at the osteotomy site using the nail to successfully restore limb length and alignment. CONCLUSION: A magnetically controlled nail can be used to perform monofocal sequential compression-distraction osteosynthesis through a nonunion after an alignment correcting osteotomy.


Asunto(s)
Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas/métodos , Fracturas no Consolidadas/cirugía , Osteogénesis por Distracción/métodos , Anciano , Femenino , Fijación Intramedular de Fracturas/instrumentación , Humanos , Osteogénesis por Distracción/instrumentación
12.
Handb Clin Neurol ; 165: 269-283, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31727217

RESUMEN

Brain tumors and paraneoplastic syndromes can cause various neuropsychiatric symptoms. Rarely, psychiatric symptoms may be the initial presentation of the underlying neurologic lesion. Brain imaging studies are crucial in the diagnosis of brain tumors. Paraneoplastic syndromes are mostly immune-mediated, and antineuronal antibodies may be detected in the blood or cerebrospinal fluid. Clinical suspicion is very important in assisting the diagnostic workup. Treatment of the psychiatric symptoms depends on the nature of the symptoms. Selection of the psychotropic agent has to be done carefully to minimize complications such as seizures and delirium secondary to anticholinergic toxicity. With advances in targeted therapies, immunology, and genetics, the future appears more promising.


Asunto(s)
Autoanticuerpos/sangre , Neoplasias Encefálicas/sangre , Neoplasias Encefálicas/tratamiento farmacológico , Síndromes Paraneoplásicos del Sistema Nervioso/sangre , Síndromes Paraneoplásicos del Sistema Nervioso/tratamiento farmacológico , Humanos , Factores Inmunológicos/uso terapéutico , Encefalitis Límbica/sangre , Encefalitis Límbica/tratamiento farmacológico , Encefalitis Límbica/psicología , Síndromes Paraneoplásicos del Sistema Nervioso/psicología , Psicofarmacología , Psicotrópicos/uso terapéutico
13.
J Pediatr Orthop B ; 25(5): 406-11, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27035497

RESUMEN

To identify factors predictive of the risk of conversion from closed to open reduction. International Classification of Disease-9 codes were used to identify completely displaced pediatric supracondylar humerus fractures that were subjected to planned closed reduction and percutaneous pinning. Clinical and radiographic variables were retrospectively collected. Compared with posterior extension fractures, flexion (risk ratio: 34.1, 95% confidence interval: 8.1-143.6, P<0.0001) and posterolateral extension (risk ratio: 6.0, 95% confidence interval: 1.3-27.5, P=0.0221) fractures were significantly more likely to undergo conversion from closed to open reduction. The direction of displacement should be considered during the preoperative evaluation of supracondylar fractures.


Asunto(s)
Clavos Ortopédicos , Fracturas del Húmero/cirugía , Reducción Abierta , Niño , Preescolar , Femenino , Fijación Interna de Fracturas , Fijación Intramedular de Fracturas , Humanos , Masculino , Complicaciones Posoperatorias , Periodo Posoperatorio , Rango del Movimiento Articular , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
14.
World J Psychiatry ; 5(3): 273-85, 2015 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-26425442

RESUMEN

Infrequently, psychiatric symptoms may be the only manifestation of brain tumors. They may present with mood symptoms, psychosis, memory problems, personality changes, anxiety, or anorexia. Symptoms may be misleading, complicating the clinical picture. A comprehensive review of the literature was conducted regarding reports of brain tumors and psychiatric symptoms from 1956-2014. Search engines used include PubMed, Ovid, Psych Info, MEDLINE, and MedScape. Search terms included psychiatric manifestations/symptoms, brain tumors/neoplasms. Our literature search yielded case reports, case studies, and case series. There are no double blind studies except for post-diagnosis/-surgery studies. Early diagnosis is critical for improved quality of life. Symptoms that suggest work-up with neuroimaging include: new-onset psychosis, mood/memory symptoms, occurrence of new or atypical symptoms, personality changes, and anorexia without body dysmorphic symptoms. This article reviews the existing literature regarding the diagnosis and management of this clinically complex condition.

15.
World J Psychiatry ; 4(4): 72-9, 2014 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-25540722

RESUMEN

Dementia is a clinical syndrome with features of neurocognitive decline. Subtypes of dementia include Alzheimer's, frontotemporal, Parkinson's, Lewy body disease, and vascular type. Dementia is associated with a variety of neuropsychiatric symptoms that may include agitation, psychosis, depression, and apathy. These symptoms can lead to dangerousness to self or others and are the main source for caregiver burnout. Treatment of these symptoms consists of nonpharmacological and pharmacological interventions. However, there are no Food and Drug Administration-approved medications for the treatment of behavioral and psychological symptoms of dementia. Pharmacological interventions are used off-label. This article reviews the current evidence supporting or negating the use of psychotropic medications along with safety concerns, monitoring, regulations, and recommendations.

16.
Environ Sci Technol ; 41(20): 6955-60, 2007 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-17993134

RESUMEN

Glaciers in the tropical Andes are undergoing rapid retreat with potentially devastating consequences for populations who rely on them for water resources. We measured stable water isotope ratios in synoptically sampled streams discharging from glacierized watersheds to associate hydroisotopic variation with relative changes in glacierized area. A total of 73 water samples were collected from hydrological endmembers including streams, glacier meltwater, and groundwater during the dry seasons of 2004-2006 in the Callejon de Huaylas, a 5000 km2 watershed that drains the western side of the Cordillera Blanca in northern Perú. To differentiate the influence of elevation on isotopic values, we use samples from shallow groundwater springs and nonglacierized subcatchments to derive a local meteoric elevation effect. From published historical runoff data and satellite-mapped glacier cover, we estimate an average increase of 1.6 (+/-1.1)% in the specific discharge of the glacierized catchments as a function of isotopic changes from 2004 to 2006. These results confirm predicted short-term increases in discharge as glaciers melt and demonstrate the utility of stable isotopes in water for tracing relative glacier melt water contributions to watersheds.


Asunto(s)
Efecto Invernadero , Hielo , Isótopos/análisis , Agua/química , Perú
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