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Characterizing the diverse, root-associated fungi in mine wastes can accelerate the development of bioremediation strategies to stabilize heavy metals. Ascomycota fungi are well known for their mutualistic associations with plant roots and, separately, for roles in the accumulation of toxic compounds from the environment, such as heavy metals. We sampled soils and cultured root-associated fungi from blue grama grass (Bouteloua gracilis) collected from lands with a history of uranium (U) mining and contrasted against communities in nearby, off-mine sites. Plant root-associated fungal communities from mine sites were lower in taxonomic richness and diversity than root fungi from paired, off-mine sites. We assessed potential functional consequences of unique mine-associated soil microbial communities using plant bioassays, which revealed that plants grown in mine soils in the greenhouse had significantly lower germination, survival, and less total biomass than plants grown in off-mine soils but did not alter allocation patterns to roots versus shoots. We identified candidate culturable root-associated Ascomycota taxa for bioremediation and increased understanding of the biological impacts of heavy metals on microbial communities and plant growth.
Assuntos
Ascomicetos , Urânio , Solo , New Mexico , Fungos , Plantas/microbiologia , Poaceae , Raízes de Plantas/microbiologiaRESUMO
Fungal symbionts can buffer plants from environmental extremes and may affect host capacities to acclimate, adapt, or redistribute under environmental change; however, the distributions of fungal symbionts along abiotic gradients are poorly described. Fungal mutualists should be the most beneficial in abiotically stressful environments, and the structure of networks of plant-fungal interactions likely shift along gradients, even when fungal community composition does not track environmental stress. We sampled 634 unique combinations of fungal endophytes and mycorrhizal fungi, grass species identities, and sampling locations from 66 sites across six replicate altitudinal gradients in the western Colorado Rocky Mountains. The diversity and composition of leaf endophytic, root endophytic, and arbuscular mycorrhizal (AM) fungal guilds and the overall abundance of fungal functional groups (pathogens, saprotrophs, mutualists) tracked grass host identity more closely than elevation. Network structures of root endophytes become more nested and less specialized at higher elevations, but network structures of other fungal guilds did not vary with elevation. Overall, grass species identity had overriding influence on the diversity and composition of above- and belowground fungal endophytes and AM fungi, despite large environmental variation. Therefore, in our system climate change may rarely directly affect fungal symbionts. Instead, fungal symbiont distributions will most likely track the range dynamics of host grasses.
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Background: Bronchodilator therapy is a foundation of chronic obstructive pulmonary disease (COPD) exacerbation treatment. Although international guidelines recommend short-acting formulations given multiple times per day, long-acting formulations have not been adequately evaluated. The objective of our study was to determine the effectiveness of umeclidinium-vilanterol (UME/VIL), long-acting beta2-agonist/long-acting muscarinic antagonist (LABA/LAMA) as a once-daily alternative for treating COPD exacerbations in hospitalized patients. Methods: In this retrospective sequential period analysis, we reviewed electronic medical records of patients hospitalized for COPD exacerbations before (September 1, 2015 to February 29, 2016) and after (April 1, 2016 to September 30, 2016) incorporation of UME/VIL into our standard COPD protocol. Before implementation, patients received a daily anticholinergic plus twice-daily long-acting beta2-agonist therapy (tiotropium plus formoterol, n=65). After implementation, UME/VIL replaced the previous regimen (n=58). No other changes were made to the COPD protocol. The primary outcome was 30-day hospital readmission rate. Hospital length of stay, 30-day mortality, and cost of care were analyzed as secondary outcomes. Results: A trend toward increased 30-day readmission rates in the post-intervention group (24.1% versus 10.8%, p=0.049) was no longer statistically significant after adjustment for severity of illness (based on case-mix index) and complications or comorbidities based on diagnosis-related group codes (adjusted odds ratio: 2.499; 95% confidence interval: 0.916-7.380; p=0.074). Conclusion: After adjustment for potential confounders,the implementation of a LABA/LAMA combination product was not statistically associated with an increased 30-day readmission rate but was associated with lower cost of care.
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OBJECTIVE: To compare 1-dimensional (1D) and 3-dimensional (3D) volume measurements and determine whether primary tumor (PT) burden is predictive of overall survival (OS) following cytoreductive nephrectomy (CN) for metastatic renal cell carcinoma (mRCC). MATERIALS AND METHODS: Records and imaging studies of patients with mRCC treated with CN from 2006 to 2015 were included, with tumor volumes measured by a faculty radiologist blinded to clinical outcomes using Advantage Workstation Volume Share (Ver 4.6, GE, Waukesha, WI). RESULTS: Complete PT and metastatic tumor volumes were measured for 67 patients. For 15 (22.3%) patients, 1D volume was within ±10% of the measured 3D volume. In 40 (59.7%) patients, the 1D calculated PT volume was >10% of the actual 3D volume. Fractional percentage of tumor volume (FPTV) removed during CN was calculated using the formula PT volume/(PT + met volume). FPTV was not associated with OS when analyzed as a continuous variable. Patients were divided into 2 groups based on previously published cut point of 90% FPTV. No differences between cohorts in age, gender, grade, subtype, number of metastatic sites, performance status, Memorial Sloan Kettering Cancer Center risk group, or International Metastatic Renal Cell Carcinoma Database Consortium risk group were identified. OS was not different between cohorts (P = .38). CONCLUSION: 1D measurements of PT diameter frequently overestimate mRCC PT volume. In patients with mRCC selected for CN, the ratio of primary to metastatic tumor does not predict OS.
Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/secundário , Procedimentos Cirúrgicos de Citorredução , Neoplasias Renais/diagnóstico , Neoplasias Renais/mortalidade , Nefrectomia , Idoso , Carcinoma de Células Renais/cirurgia , Estudos de Coortes , Feminino , Humanos , Imageamento Tridimensional , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Taxa de Sobrevida , Carga TumoralRESUMO
OBJECTIVE: To evaluate if body mass index (BMI) ≥ 40 is associated with risk of postoperative complications, receipt of perioperative blood transfusion (PBT), length of hospital stay (LOS), perioperative death, or hospital readmission rate following renal mass surgery. MATERIALS AND METHODS: After Institutional Review Board approval, comprehensive information was collected for patients treated with surgery for renal mass from 2000 to 2015 at one institution. Univariable and multivariable analyses were used to evaluate the association of BMI ≥ 40 among other putative risk factors for perioperative outcomes. RESULTS: A total of 1048 patients were treated surgically, including 115 (11%) with BMI > 40. Minimally invasive and open surgical approaches were used for 480 (45.8%) and 568 (54.2%) patients, respectively. Morbid obesity was not associated with risk of major complications, overall complications, receipt of PBT, LOS, hospital readmission rate, or perioperative death. Charlson comorbidity index was the only independent predictor of major complications following renal mass surgery, P = .0006, per point odds ratio 1.2 (95%C.I. 1.08-1.32). Surgical site infections (SSIs) were more common in patients with BMI ≥ 40 vs BMI < 40 (10.5% vs 4.8%, P = .01). Following multivariable analysis, BMI ≥ 40 was the only independent predictor of SSIs, odds ratio 2.6, 95% confidence interval 1.32-5.13; P = .006. CONCLUSION: Morbid obesity (BMI ≥ 40) is an independent predictor of developing SSIs following renal mass surgery. Morbid obesity is not predictive of risk for major complications, receipt of PBT, hospital readmission, perioperative death, or LOS.