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1.
Circ Res ; 133(7): 542-558, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37646165

RESUMO

BACKGROUND: Using proteomics, we aimed to reveal molecular types of human atherosclerotic lesions and study their associations with histology, imaging, and cardiovascular outcomes. METHODS: Two hundred nineteen carotid endarterectomy samples were procured from 120 patients. A sequential protein extraction protocol was employed in conjunction with multiplexed, discovery proteomics. To focus on extracellular proteins, parallel reaction monitoring was employed for targeted proteomics. Proteomic signatures were integrated with bulk, single-cell, and spatial RNA-sequencing data, and validated in 200 patients from the Athero-Express Biobank study. RESULTS: This extensive proteomics analysis identified plaque inflammation and calcification signatures, which were inversely correlated and validated using targeted proteomics. The inflammation signature was characterized by the presence of neutrophil-derived proteins, such as S100A8/9 (calprotectin) and myeloperoxidase, whereas the calcification signature included fetuin-A, osteopontin, and gamma-carboxylated proteins. The proteomics data also revealed sex differences in atherosclerosis, with large-aggregating proteoglycans versican and aggrecan being more abundant in females and exhibiting an inverse correlation with estradiol levels. The integration of RNA-sequencing data attributed the inflammation signature predominantly to neutrophils and macrophages, and the calcification and sex signatures to smooth muscle cells, except for certain plasma proteins that were not expressed but retained in plaques, such as fetuin-A. Dimensionality reduction and machine learning techniques were applied to identify 4 distinct plaque phenotypes based on proteomics data. A protein signature of 4 key proteins (calponin, protein C, serpin H1, and versican) predicted future cardiovascular mortality with an area under the curve of 75% and 67.5% in the discovery and validation cohort, respectively, surpassing the prognostic performance of imaging and histology. CONCLUSIONS: Plaque proteomics redefined clinically relevant patient groups with distinct outcomes, identifying subgroups of male and female patients with elevated risk of future cardiovascular events.


Assuntos
Aterosclerose , Calcinose , Feminino , Humanos , Masculino , Proteômica , Caracteres Sexuais , Versicanas , alfa-2-Glicoproteína-HS
2.
Proc Natl Acad Sci U S A ; 119(39): e2200333119, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36122238

RESUMO

Wildfire area has been increasing in most ecoregions across the western United States, including snow-dominated regions. These fires modify snow accumulation, ablation, and duration, but the sign and magnitude of these impacts can vary substantially between regions. This study compares spatiotemporal patterns of western United States wildfires between ecoregions and snow zones. Results demonstrate significant increases in wildfire area from 1984 to 2020 throughout the West, including the Sierra Nevada, Cascades, Basin and Range, and Northern to Southern Rockies. In the late snow zone, where mean annual snow-free date is in May or later, 70% of ecoregions experienced significant increases in wildfire area since 1984. The distribution of burned area shifted from earlier melt zones to later-melt snow zones in several ecoregions, including the Southern Rockies, where the area burned in the late snow zone during 2020 exceeded the total burned area over the previous 36 y combined. Snow measurements at a large Southern Rockies fire revealed that burning caused lower magnitude and earlier peak snow-water equivalent as well as an 18-24 d estimated advance in snow-free dates. Latitude, a proxy for solar radiation, is a dominant driver of snow-free date, and fire advances snow-free timing through a more-positive net shortwave radiation balance. This loss of snow can reduce both ecosystem water availability and streamflow generation in a region that relies heavily on mountain snowpack for water supply.


Assuntos
Incêndios , Neve , Incêndios Florestais , Ecossistema , Estados Unidos , Água , Abastecimento de Água
3.
Eur J Vasc Endovasc Surg ; 65(4): 474-483, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36529365

RESUMO

OBJECTIVE: Carotid atherosclerosis is an important cause of cerebral ischaemic stroke. Sonographic plaque characteristics are inappropriate for exact prediction of possible future ischaemic events. Additional markers are needed to predict the clinical outcome in high grade carotid stenosis. This study aimed to test extracellular matrix metalloproteinase inducer (EMMPRIN), due to its involvement in plaque formation and destabilisation, as a potential marker of high risk vulnerable plaques. METHODS: EMMPRIN was analysed in pre-operative serum samples from patients with symptomatic and asymptomatic carotid artery stenosis by a specific ELISA. Pre-operative duplex sonography classified the atherosclerotic plaque due to echogenicity. Histopathological analysis of vulnerable and non-vulnerable plaques was based on the American Heart Association (AHA) classification. RESULTS: The study included 265 patients undergoing carotid endarterectomy: 90 (m:f, 69:21) patients with symptomatic and 175 (m:f, 118:57) with asymptomatic disease. Analysis of circulating EMMPRIN revealed significantly higher levels in patients with echolucent plaques (4 480; IQR 3 745, 6 144 pg/mL) compared with echogenic plaques (4 159; IQR 3 418, 5 402 pg/mL; p = .025). Asymptomatic patients with vulnerable plaques had significantly higher levels of EMMPRIN (4 875; IQR 3 850, 7 016 pg/mL) compared with non-vulnerable plaques (4 109; IQR 3 433, 5 402 pg/mL; p < .001). In logistic regression analysis, duplex sonography combined with age, gender, and clinical risk factors predicted vulnerable plaques in asymptomatic patients with an AUC of 0.71 (95% CI 0.61 - 0.80). EMMPRIN significantly improved the AUC in asymptomatic patients (AUC 0.79; 95% CI 0.71 - 0.87; p = .014). CONCLUSION: Patients with high risk plaques according to ultrasound and histopathological characteristics demonstrated increased serum EMMPRIN levels. EMMPRIN on top of clinical risk factors, including age, gender, and duplex sonography may be used for pre-operative risk stratification in asymptomatic patients.


Assuntos
Isquemia Encefálica , Estenose das Carótidas , Placa Aterosclerótica , Acidente Vascular Cerebral , Humanos , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Placa Aterosclerótica/patologia , Basigina , Artérias Carótidas/patologia
4.
Int J Mol Sci ; 24(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37240352

RESUMO

Interleukin (IL-33) and the ST2 receptor are implicated in the pathogenesis of atherosclerosis. Soluble ST2 (sST2), which negatively regulates IL-33 signaling, is an established biomarker in coronary artery disease and heart failure. Here we aimed to investigate the association of sST2 with carotid atherosclerotic plaque morphology, symptom presentation, and the prognostic value of sST2 in patients undergoing carotid endarterectomy. A total of 170 consecutive patients with high-grade asymptomatic or symptomatic carotid artery stenosis undergoing carotid endarterectomy were included in the study. The patients were followed up for 10 years, and the primary endpoint was defined as a composite of adverse cardiovascular events and cardiovascular mortality, with all-cause mortality as the secondary endpoint. The baseline sST2 showed no association with carotid plaque morphology assessed using carotid duplex ultrasound (B 0.051, 95% CI -0.145-0.248, p = 0.609), nor with modified histological AHA classification based on morphological description following surgery (B -0.032, 95% CI -0.194-0.130, p = 0.698). Furthermore, sST2 was not associated with baseline clinical symptoms (B -0.105, 95% CI -0.432-0.214, p = 0.517). On the other hand, sST2 was an independent predictor for long-term adverse cardiovascular events after adjustment for age, sex, and coronary artery disease (HR 1.4, 95% CI 1.0-2.4, p = 0.048), but not for all-cause mortality (HR 1.2, 95% CI 0.8-1.7, p = 0.301). Patients with high baseline sST2 levels had a significantly higher adverse cardiovascular event rate as compared to patients with lower sST2 (log-rank p < 0.001). Although IL-33 and ST2 play a role in the pathogenesis of atherosclerosis, sST2 is not associated with carotid plaque morphology. However, sST2 is an excellent prognostic marker for long-term adverse cardiovascular outcomes in patients with high-grade carotid artery stenosis.


Assuntos
Aterosclerose , Estenose das Carótidas , Doença da Artéria Coronariana , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/patologia , Estenose das Carótidas/complicações , Estenose das Carótidas/cirurgia , Doença da Artéria Coronariana/diagnóstico , Interleucina-33 , Proteína 1 Semelhante a Receptor de Interleucina-1 , Aterosclerose/complicações , Biomarcadores
5.
BMC Pregnancy Childbirth ; 21(1): 587, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34445988

RESUMO

BACKGROUND: The coronavirus disease (COVID-19) pandemic has caused ongoing challenges in health services worldwide. Despite the growing body of literature on COVID-19, reports on perinatal care in COVID-19 cases are limited. CASE PRESENTATION: We describe a case of severe acute respiratory distress syndrome (ARDS) in a 36-year-old G5/P2 pregnant woman with morbid obesity, confirmed severe acute respiratory syndrome coronavirus 2 infection, and fulminant respiratory failure. At 28+ 1 gestational weeks, the patient delivered an uninfected newborn. Using ImmunoCAP ISAC® technology, we found no immunoglobulin (Ig) M antibodies, suggesting that no mother-to-child viral transmission occurred during pregnancy or delivery. The maternal respiratory state improved rapidly after delivery; both maternal and neonatal outcomes were encouraging given the early gestational age and fulminant course of respiratory failure in our patient. CONCLUSIONS: The management of ARDS in pregnant women with COVID-19 is complex and requires an individualized, multidisciplinary approach, while considering maternal and fetal outcomes.


Assuntos
COVID-19 , Cesárea/métodos , Pneumonia Viral , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Síndrome do Desconforto Respiratório , SARS-CoV-2/isolamento & purificação , Adulto , COVID-19/complicações , COVID-19/diagnóstico , Feminino , Monitorização Fetal/métodos , Idade Gestacional , Humanos , Obesidade Mórbida/diagnóstico , Obesidade Mórbida/fisiopatologia , Equipe de Assistência ao Paciente/organização & administração , Assistência Perinatal/métodos , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/etiologia , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/fisiopatologia , Complicações Infecciosas na Gravidez/terapia , Complicações Infecciosas na Gravidez/virologia , Resultado da Gravidez , Nascimento Prematuro/etiologia , Nascimento Prematuro/terapia , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/fisiopatologia , Síndrome do Desconforto Respiratório/terapia , Resultado do Tratamento
7.
J Environ Manage ; 268: 110704, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32510439

RESUMO

Land managers often need to predict watershed-scale erosion rates after disturbance or other land cover changes. This study compared commonly used hillslope erosion models to simulate post-fire sediment yields (SY) at both hillslope and watershed scales within the High Park Fire, Colorado, U.S.A. At hillslope scale, simulated SY from four models- RUSLE, AGWA/KINEROS2, WEPP, and a site-specific regression model-were compared to observed SY at 29 hillslopes. At the watershed scale, RUSLE, AGWA/KINEROS2, and WEPP were applied to simulate spatial patterns of SY for two 14-16 km2 watersheds using different scales (0.5-25 ha) of hillslope discretization. Simulated spatial patterns were compared between models and to densities of channel heads across the watersheds. Three additional erosion algorithms were implemented within a land surface model to evaluate effects of parameter uncertainty. At the hillslope scale, SY was only significantly correlated to observed SY for the empirical model, but at the watershed scale, sediment loads were significantly correlated to observed channel head densities for all models. Watershed sediment load increased with the size of the hillslope sub-units due to the nonlinear effects of hillslope length on simulated erosion. SY's were closest in magnitude to expected watershed-scale SY when models were divided into the smallest hillslopes. These findings demonstrate that current erosion models are fairly consistent at identifying areas with low and high erosion potential, but the wide range of predicted SY and poor fit to observed SY highlight the need for better field observations and model calibration to obtain more accurate simulations.


Assuntos
Incêndios , Sedimentos Geológicos , Colorado , Monitoramento Ambiental , Modelos Teóricos , Solo
8.
J Environ Manage ; 198(Pt 2): 66-77, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28501609

RESUMO

A small but growing number of watershed investment programs in the western United States focus on wildfire risk reduction to municipal water supplies. This paper used return on investment (ROI) analysis to quantify how the amounts and placement of fuel treatment interventions would reduce sediment loading to the Strontia Springs Reservoir in the Upper South Platte River watershed southwest of Denver, Colorado following an extreme fire event. We simulated various extents of fuel mitigation activities under two placement strategies: (a) a strategic treatment prioritization map and (b) accessibility. Potential fire behavior was modeled under each extent and scenario to determine the impact on fire severity, and this was used to estimate expected change in post-fire erosion due to treatments. We found a positive ROI after large storm events when fire mitigation treatments were placed in priority areas with diminishing marginal returns after treating >50-80% of the forested area. While our ROI results should not be used prescriptively they do show that, conditional on severe fire occurrence and precipitation, investments in the Upper South Platte could feasibly lead to positive financial returns based on the reduced costs of dredging sediment from the reservoir. While our analysis showed positive ROI focusing only on post-fire erosion mitigation, it is important to consider multiple benefits in future ROI calculations and increase monitoring and evaluation of these benefits of wildfire fuel reduction investments for different site conditions and climates.


Assuntos
Conservação dos Recursos Naturais/economia , Incêndios , Investimentos em Saúde , Colorado , Desastres , Florestas , Estados Unidos
9.
Cardiovasc Diabetol ; 13: 6, 2014 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-24393402

RESUMO

BACKGROUND: Type 2 diabetes mellitus (T2DM) is often associated with atherosclerotic changes in coronary vessels, most notably plaques. The angiostatic parameter endostatin is able to inhibit angiogenesis in tissue as well as in plaques and therefore plays an important role in physiological and pathological neovascularisation. The aim of the present study was to investigate sex-specific differences and the influence of exercise on circulating endostatin levels in patients suffering from diabetes, and control subjects. METHODS: In total, 42 T2DM-patients and 45 control subjects were investigated. They underwent a graded physical stress test (ergometry). Serum endostatin levels were measured in venous blood at rest and directly after reaching maximum workload. RESULTS: Females showed significantly higher endostatin levels at baseline measurements compared to men, independently of their underlying disease. In both female and male T2DM-patients endostatin levels were significantly lower compared to controls. Both groups and sexes showed a significant increase of endostatin after physical stress, whereas the extent of endostatin-increase was between 10.59-15.05%. CONCLUSION: Middle-aged healthy female individuals as well as female T2DM-patients showed higher circulating serum endostatin levels compared to males, suggesting a hormonal influence on baseline circulating endostatin amounts. Exercise-induced increase in endostatin is also observable in patients suffering from T2DM. Concerning vascularisation, lower endostatin levels in T2DM might be advantageous. Concerning plaque stability, lower levels might be prejudicial. TRIAL REGISTRATION: Clinical Trial Registration-URL: http://clinicaltrials.gov/ct2/results?term=NCT01165515.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Endostatinas/sangue , Exercício Físico/fisiologia , Caracteres Sexuais , Idoso , Biomarcadores/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Teste de Esforço/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Science ; 384(6703): 1402-1403, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38935734

RESUMO

Streams that only flow occasionally are major contributors to river flow.

11.
Breast Care (Basel) ; 19(4): 215-222, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39185129

RESUMO

Background: Oncoplastic surgery has become an important part of the surgical repertoire to offer both oncologically safe and aesthetically pleasing results in patients with breast cancer. Data comparing oncoplastic and reconstructive breast surgeries are limited. This study aimed to assess patient-reported outcomes (PRO) in our cohort of oncoplastic and reconstructively operated patients. Methods: Patients who underwent oncoplastic surgery, including immediate reconstruction by a single surgeon, between 2010 and 2018 were contacted to participate in this study. In total, 157 patients fulfilled the inclusion criteria. 54 patient data sets were used for statistical evaluation. Body Image Scale (BIS) and BreastQ questionnaires were used to measure subjective PRO scores, and pictures were taken to objectively measure symmetry using the Breast Analyzing Tool (BAT). Patients were divided into three groups according to the Tübingen classification (group 1: Tübingen 3-4 (n = 16), group 2: Tübingen 5 (n = 26), group 3: Breast Reconstruction/Tübingen 6 (n = 12]). Results: The mean age was 53.5 for group 1, 51.4 for group 2 and 46.8 for group 3. The mean follow-up was 62.9 ± 35.82 months. BIS was significantly better in group 3 (3.92 ± 1.73) than in group 1 and 2 (7.69 ± 4.48 and 4.81 ± 3.41, p = 0.016). Symmetry measured using BAT showed only a trend favoring reconstruction (p = 0.12). The BreastQ item "Sexual well-being" was significantly better in oncoplastic breast reduction surgery (p = 0.036). Conclusion: BIS was better after reconstructive breast surgery than after oncoplastic surgery. Reconstructive breast surgery in experienced breast care units offers high patient satisfaction and a high quality of life.

12.
Curr Opin Anaesthesiol ; 26(5): 543-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23963230

RESUMO

PURPOSE OF REVIEW: Maintenance of adequate blood flow and oxygen to the brain is one of the principal endpoints of all surgery and anesthesia. During operations in general anesthesia, however, the brain is at particular risk for silent ischemia. Despite this risk, the brain still remains one of the last monitored organs in clincial anesthesiology. RECENT FINDINGS: Transcranial Doppler (TCD) sonography and near-infrared spectroscopy (NIRS) experience a revival as these noninvasive technologies help to detect silent cerebral ischemia. TCD allows for quantification of blood flow velocities in basal intracranial arteries. TCD-derived variables such as the pulsatility index might hint toward diminished cognitive reserve or raised intracranial pressure. NIRS allows for assessment of regional cerebral oxygenation. Monitoring should be performed during high-risk surgery for silent cerebral ischemia and special circumstances during critical care medicine. Both techniques allow for the assessment of cerebrovascular autoregulation and individualized management of cerebral hemodynamics. SUMMARY: TCD and NIRS are noninvasive monitors that anesthesiologists apply to tailor cerebral oxygen delivery, aiming to safeguard brain function in the perioperative period.


Assuntos
Circulação Cerebrovascular , Espectroscopia de Luz Próxima ao Infravermelho , Ultrassonografia Doppler Transcraniana , Encéfalo/metabolismo , Morte Encefálica/diagnóstico , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/diagnóstico por imagem , Procedimentos Cirúrgicos Cardíacos , Humanos , Procedimentos Neurocirúrgicos , Oxigênio/metabolismo , Período Perioperatório , Procedimentos Cirúrgicos Vasculares
13.
Hepatobiliary Surg Nutr ; 12(5): 704-714, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37886202

RESUMO

Background: Obesity and associated steatosis is an increasing health problem worldwide. Its influence on post-hepatectomy liver failure (PHLF) and after liver resection (LR) is still unclear. Methods: Patients who underwent LR were investigated and divided into three groups [normal weight: body mass index (BMI) 18.5-24.9 kg/m2, overweight: BMI 25.0-29.9 kg/m2, obese: BMI ≥30 kg/m2] in this retrospective study. Primary aim of this study was to assess the influence of BMI and nonalcoholic steatohepatitis (NASH) on PHLF and morbidity. Results: Of 888 included patients, 361 (40.7%) had normal weight, 360 (40.5%) were overweight, 167 (18.8%) were obese. Median age was 62.5 years (IQR, 54-69 years). The primary indication for LR was colorectal liver metastases (CLM) (n=366, 41.2%). NASH was present in 58 (16.1%) of normal weight, 84 (23.3%) of overweight and 69 (41.3%) of obese patients (P<0.001). PHLF occurred in 16.3% in normal weight, 15.3% in overweight and 11.4% in obese patients (P=0.32). NASH was not associated with PHLF. There was no association between patients' weight and the occurrence of postoperative complications (P=0.45). At multivariable analysis, solely major LR [odds ratio (OR): 2.7, 95% confidence interval (CI): 1.83-4.04; P<0.001] remained a significant predictor for PHLF. Conclusions: Postoperative complications and PHLF are comparable in normal weight, overweight and obese patients and LRs using modern techniques can be safely performed in these patients.

14.
Nat Food ; 4(8): 664-672, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37550540

RESUMO

Wildfires are a growing concern to society and the environment in many parts of the world. Within the United States, the land area burned by wildfires has steadily increased over the past 40 years. Agricultural land management is widely understood as a force that alters fire regimes, but less is known about how wildfires, in turn, impact the agriculture sector. Based on an extensive literature review, we identify three pathways of impact-direct, downwind and downstream-through which wildfires influence agricultural resources (soil, water, air and photosynthetically active radiation), labour (agricultural workers) and products (crops and livestock). Through our pathways framework, we highlight the complexity of wildfire-agriculture interactions and the need for collaborative, systems-oriented research to better quantify the magnitude of wildfire impacts and inform the adaptation of agricultural systems to an increasingly fire-prone future.


Assuntos
Incêndios , Incêndios Florestais , Humanos , Estados Unidos , Agricultura , Água , Previsões
15.
Freshw Sci ; 41(2): 167-182, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35846249

RESUMO

Nonperennial streams dominate global river networks and are increasing in occurrence across space and time. When surface flow ceases or the surface water dries, flow or moisture can be retained in the subsurface sediments of the hyporheic zone, supporting aquatic communities and ecosystem processes. However, hydrological and ecological definitions of the hyporheic zone have been developed in perennial rivers and emphasize the mixing of water and organisms, respectively, from both the surface stream and groundwater. The adaptation of such definitions to include both humid and dry unsaturated conditions could promote characterization of how hydrological and biogeochemical variability shape ecological communities within nonperennial hyporheic zones, advancing our understanding of both ecosystem structure and function in these habitats. To conceptualize hyporheic zones for nonperennial streams, we review how water sources and surface and subsurface structure influence hydrological and physicochemical conditions. We consider the extent of this zone and how biogeochemistry and ecology might vary with surface states. We then link these components to the composition of nonperennial stream communities. Next, we examine literature to identify priorities for hydrological and ecological research exploring nonperennial hyporheic zones. Lastly, by integrating hydrology, biogeochemistry, and ecology, we recommend a multidisciplinary conceptualization of the nonperennial hyporheic zone as the porous subsurface streambed sediments that shift between lotic, lentic, humid, and dry conditions in space and time to support aquatic-terrestrial biodiversity. As river drying increases in extent because of global change, we call for holistic, interdisciplinary research across the terrestrial and aquatic sciences to apply this conceptualization to characterize hyporheic zone structure and function across the full spectrum of hydrological states.

16.
Sci Rep ; 11(1): 16321, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381065

RESUMO

Vascular bypass surgery in children differs significantly from adults. It is a rarely performed procedure in the setting of trauma and tumor surgery. Besides technical challenges to reconstruct the small and spastic vessels, another concern in bypass grafting is the adequate limb length growth over time. The primary aim of this study was to assess long-term outcome after pediatric bypass grafting, in a single academic center, focusing on potential effects on limb development. In this retrospective cohort analyses we included all pediatric patients undergoing vascular bypass grafting at our department between 2002 and 2017. All patients ≤ 18 years suffered a traumatic injury or underwent a tumor resection of the lower or upper limb. The youngest female patient was 0.4 years, the youngest male patient was 3.5 years. During the observation period, 33 pediatric patients underwent vascular repair, whereby 15 patients underwent bypass grafting. Median overall follow-up was 4.7 years (IQR ± 9). 8 patients (53%) had a traumatic injury (traumatic surgery group) and 7 patients had a planned orthopedic tumor resection (orthopedic surgery group). In 13/15 (87%) a great saphenous vein (GSV) graft and in 2/15 (13%) a Gore-Tex graft was used for bypassing. Both Gore-Tex grafts showed complete occlusion 12 and 16 years after implantation. No patient died in the early postoperative phase (< 30 days), however 3/7 (43%) in the orthopedic group died during follow-up. Revision surgery had to be performed in 1/15 (7%) patients. A functional use of the extremity was reported in all patients. Normal limb length growth according to the contralateral site, and therefore bypass growth, could be documented in 14/15 patients. Children are surgically challenging. In our study, surgery by a specialized vascular surgery team using GSV grafts led to adequate limb length and bypass growth, and we observed no functional restrictions.


Assuntos
Oclusão de Enxerto Vascular/fisiopatologia , Neoplasias/fisiopatologia , Criança , Feminino , Oclusão de Enxerto Vascular/cirurgia , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Neoplasias/cirurgia , Politetrafluoretileno/química , Estudos Retrospectivos , Veia Safena/fisiopatologia , Veia Safena/cirurgia , Resultado do Tratamento , Extremidade Superior/fisiopatologia , Enxerto Vascular/métodos , Grau de Desobstrução Vascular/fisiologia , Procedimentos Cirúrgicos Vasculares/métodos
17.
Water (Basel) ; 13(12): 1-20, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35342643

RESUMO

Observations of the presence or absence of surface water in streams are useful for characterizing streamflow permanence, which includes the frequency, duration, and spatial extent of surface flow in streams and rivers. Such data are particularly valuable for headwater streams, which comprise the vast majority of channel length in stream networks, are often non-perennial, and are frequently the most data deficient. Datasets of surface water presence exist across multiple data collection groups in the United States but are not well aligned for easy integration. Given the value of these data, a unified approach for organizing information on surface water presence and absence collected by diverse surveys would facilitate more effective and broad application of these data and address the gap in streamflow data in headwaters. In this paper, we highlight the numerous existing datasets on surface water presence in headwater streams, including recently developed crowdsourcing approaches. We identify the challenges of integrating multiple surface water presence/absence datasets that include differences in the definitions and categories of streamflow status, data collection method, spatial and temporal resolution, and accuracy of geographic location. Finally, we provide a list of critical and useful components that could be used to integrate different streamflow permanence datasets.

18.
WIREs Water ; 7(3)2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32802326

RESUMO

Streamflow observations can be used to understand, predict, and contextualize hydrologic, ecological, and biogeochemical processes and conditions in streams. Stream gages are point measurements along rivers where streamflow is measured, and are often used to infer upstream watershed-scale processes. When stream gages read zero, this may indicate that the stream has fully dried; however, zero-flow readings can also be caused by a wide range of other factors. Our ability to identify whether or not a zero-flow gage reading indicates a dry fluvial system has far reaching environmental implications. Incorrect identification and interpretation by the data user can lead to hydrologic, ecological, and/or biogeochemical predictions from models and analyses. Here, we describe several causes of zero-flow gage readings: frozen surface water, flow reversals, instrument error, and natural or human-driven upstream source losses or bypass flow. For these examples, we discuss the implications of zero-flow interpretations. We also highlight additional methodss for determining flow presence, including direct observations, statistical methods, and hydrologic models, which can be applied to interpret causes of zero-flow gage readings and implications for reach- and watershed-scale dynamics. Such efforts are necessary to improve our ability to understand and predict surface flow activation, cessation, and connectivity across river networks. Developing this integrated understanding of the wide range of possible meanings of zero-flows will only attain greater importance in a more variable and changing hydrologic climate.

19.
WIREs Water ; 7(5)2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-33365126

RESUMO

Conceptual models underpin river ecosystem research. However, current models focus on continuously flowing rivers and few explicitly address characteristics such as flow cessation and drying. The applicability of existing conceptual models to nonperennial rivers that cease to flow (intermittent rivers and ephemeral streams, IRES) has not been evaluated. We reviewed 18 models, finding that they collectively describe main drivers of biogeochemical and ecological patterns and processes longitudinally (upstream-downstream), laterally (channel-riparian-floodplain), vertically (surface water-groundwater), and temporally across local and landscape scales. However, perennial rivers are longitudinally continuous while IRES are longitudinally discontinuous. Whereas perennial rivers have bidirectional lateral connections between aquatic and terrestrial ecosystems, in IRES, this connection is unidirectional for much of the time, from terrestrial-to-aquatic only. Vertical connectivity between surface and subsurface water occurs bidirectionally and is temporally consistent in perennial rivers. However, in IRES, this exchange is temporally variable, and can become unidirectional during drying or rewetting phases. Finally, drying adds another dimension of flow variation to be considered across temporal and spatial scales in IRES, much as flooding is considered as a temporally and spatially dynamic process in perennial rivers. Here, we focus on ways in which existing models could be modified to accommodate drying as a fundamental process that can alter these patterns and processes across spatial and temporal dimensions in streams. This perspective is needed to support river science and management in our era of rapid global change, including increasing duration, frequency, and occurrence of drying.

20.
Water (Basel) ; 12(7): 1980, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-33274073

RESUMO

Rivers that cease to flow are globally prevalent. Although many epithets have been used for these rivers, a consensus on terminology has not yet been reached. Doing so would facilitate a marked increase in interdisciplinary interest as well as critical need for clear regulations. Here we reviewed literature from Web of Science database searches of 12 epithets to learn (Objective 1-O1) if epithet topics are consistent across Web of Science categories using latent Dirichlet allocation topic modeling. We also analyzed publication rates and topics over time to (O2) assess changes in epithet use. We compiled literature definitions to (O3) identify how epithets have been delineated and, lastly, suggest universal terms and definitions. We found a lack of consensus in epithet use between and among various fields. We also found that epithet usage has changed over time, as research focus has shifted from description to modeling. We conclude that multiple epithets are redundant. We offer specific definitions for three epithets (non-perennial, intermittent, and ephemeral) to guide consensus on epithet use. Limiting the number of epithets used in non-perennial river research can facilitate more effective communication among research fields and provide clear guidelines for writing regulatory documents.

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