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1.
Ecol Appl ; 32(4): e2541, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35072953

RESUMO

Potable source-water reservoirs are the main water supplies in many urbanizing regions, yet their long-term responses to cultural eutrophication are poorly documented in comparison with natural lakes, creating major management uncertainties. Here, long-term discrete data (June 2006-June 2018) for classical eutrophication water quality indicators, continuous depth-profile data for dissolved oxygen (DO), and an enhanced hybrid statistical trend analysis model were used to evaluate the eutrophication status of a potable source-water reservoir. Based on classical indicators (nitrogen, N and phosphorus, P concentrations and ratios; phytoplankton biomass as chlorophyll a, chl a; and trophic state indices), the reservoir was eutrophic to hypereutrophic and stoichiometrically imbalanced. Anoxia/hypoxia occurred for 7-8 months annually systemwide, even throughout the water column for days to weeks in some years; and elevated total ammonia (up to ~900 µg tNH3 L-1 ) in surface waters from late summer/fall through late winter/early spring suggested substantial internal legacy nutrient loading. These surprising DO and tNH3 phenomena may characterize many reservoirs in urbanizing areas, and the associated cascade of negative impacts may increasingly affect them under global warming. Total organic carbon (TOC), seasonally influenced by phytoplankton biomass, commonly exceeded 6 mg L-1 , which is problematic for potable-water treatment, and significantly trended up over time. Wet-year inflow dilution influenced an apparent decreasing trend in nutrients within the hypereutrophic upper reservoir, which receives most tributary inputs. Nevertheless, significant reservoirwide trends (increasing total phosphorus [TP], phytoplankton chl a, TOC) and mid- and/or lower region trends (increasing total nitrogen [TN], tNH3 , decreasing TN:TP ratios) suggest that water quality degradation from eutrophication has worsened over time. These findings support broadly applicable recommendations to strengthen protection of potable source-water reservoirs in urbanizing watersheds: (1) protective numeric water quality criteria are needed for TOC as well as TN, TP, and chl a; (2) continuous diel data capture more realistic DO conditions than traditional sampling, and can provide important insights for water treatment managers; and (3) assessment of reservoir eutrophication status to track management progress over time should emphasize classic indicators equally as statistical trends, which are highly sensitive to short-term meteorological forcing.


Assuntos
Água Potável , China , Clorofila/análise , Clorofila A/análise , Água Potável/análise , Monitoramento Ambiental , Eutrofização , Lagos/análise , Nitrogênio/análise , Oxigênio , Fósforo/análise , Fitoplâncton
2.
Qual Life Res ; 23(6): 1841-58, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24492945

RESUMO

PURPOSE: The Radiation Therapy Oncology Group (RTOG) conducted a randomized, placebo-controlled trial evaluating the efficacy of GM-CSF in reducing mucosal injury and symptom burden from curative radiotherapy for head and neck (H&N) cancer. METHODS: Eligible patients with H&N cancer receiving radiation encompassing ≥50 % of the oral cavity or oropharynx received subcutaneous GM-CSF or placebo. Quality of life (QoL) was assessed using the RTOG-modified University of Washington H&N Symptom Questionnaire at baseline 4, 13, 26, and 48 weeks from radiation initiation. RESULTS: Of 125 eligible patients, 114 were evaluable for QoL (58 GM-CSF, 56 placebo). Patient demographics, clinical characteristics, and baseline symptom scores were well balanced between the treatment arms. At the end of the acute period (13 weeks), patients in both arms reported negative change in total symptom score indicating increase in symptom burden relative to baseline (mean -18.4 GM-CSF, -20.8 placebo). There was no difference in change in total symptom score (p > 0.05) or change in mucous, pain, eating, or activity domain scores (p > 0.01) between patients in the GM-CSF and placebo arms. Analysis limited to patients treated per protocol or with an acceptable protocol deviation also found no difference in change in total symptom score (p > 0.05) or change in domain scores (p > 0.01) between treatment arms. Provider assessment of acute mucositis during treatment did not correlate with patient-reported mucous domain and total symptom scores (p > 0.05). CONCLUSION: GM-CSF administered concurrently during head and neck radiation does not appear to significantly improve patient-reported QoL symptom burden.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Neoplasias de Cabeça e Pescoço/psicologia , Avaliação de Resultados da Assistência ao Paciente , Qualidade de Vida , Canadá , Efeitos Psicossociais da Doença , Método Duplo-Cego , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/efeitos adversos , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/efeitos adversos , Protetores contra Radiação/uso terapêutico , Fatores Socioeconômicos , Inquéritos e Questionários , Estados Unidos
3.
Cancer ; 119(4): 888-96, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23165743

RESUMO

BACKGROUND: The Radiation Therapy Oncology Group (RTOG) trial 97-14 revealed no difference between radiation delivered for painful bone metastases at a dose of 8 gray (Gy) in 1 fraction (single-fraction radiotherapy [SFRT]) and 30 Gy in 10 fractions (multifraction radiotherapy [MFRT]) in pain relief or narcotic use 3 months after randomization. SFRT for painful vertebral bone metastases (PVBM) has not been well accepted, possibly because of concerns about efficacy and toxicity. In the current study, the authors evaluated the subset of patients that was treated specifically for patients with PVBM. METHODS: PVBM included the cervical, thoracic, and/or lumbar spine regions. Among patients with PVBM, differences in retreatment rates and in pain relief, narcotic use, and toxicity 3 months after randomization were evaluated. RESULTS: Of 909 eligible patients, 235 (26%) had PVBM. Patients with and without PVBM differed in terms of the percentage of men (55% vs 47%, respectively; P = .03) and the proportion of patients with multiple painful sites (57% vs 38%, respectively; P < .01). Among those with PVBM, more patients who received MFRT had multiple sites treated (65% vs 49% for MFRT vs SFRT, respectively; P = .02). There were no statistically significant treatment differences in terms of pain relief (62% vs 70% for MFRT vs SFRT, respectively; P = .59) or freedom from narcotic use (24% vs 27%, respectively; P = .76) at 3 months. Significant differences in acute grade 2 through 4 toxicity (20% vs 10% for MFRT vs SFRT, respectively; P = .01) and acute grade 2 through 4 gastrointestinal toxicity (14% vs 6%, respectively; P = .01) were observed at 3 months, with lower toxicities seen in the patients treated with SFRT. Late toxicity was rare. No myelopathy was recorded. SFRT produced higher 3-year retreatment rates (5% vs 15%; P = .01). CONCLUSIONS: Results for the subset of patients with PVBM in the RTOG 94-17 randomized controlled trial were comparable to those for the entire population. SFRT produced less acute toxicity and a higher rate of retreatment than MFRT. SFRT and MFRT resulted in comparable pain relief and narcotic use at 3 months.


Assuntos
Neoplasias Ósseas/radioterapia , Fracionamento da Dose de Radiação , Manejo da Dor/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/secundário , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Entorpecentes/uso terapêutico , Cuidados Paliativos , Radioterapia/efeitos adversos
4.
Cancer ; 118(17): 4244-52, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22252927

RESUMO

BACKGROUND: In this phase 2 component of a multi-institutional, phase 2/3, randomized trial, the authors assessed the feasibility and preliminary efficacy of acupuncture-like transcutaneous electrical nerve stimulation (ALTENS) in reducing radiation-induced xerostomia. METHODS: Patients with cancer of the head and neck who were 3 to 24 months from completing radiotherapy with or without chemotherapy (RT ± C) and who were experiencing xerostomia symptoms with basal whole saliva production ≥0.1 mL per minute and were without recurrence were eligible. Patients received twice weekly ALTENS sessions (24 sessions over 12 weeks) using a proprietary electrical stimulation unit. The primary study objective was to assess the feasibility of ALTENS treatment. Patients were considered compliant if 19 of 24 ALTENS sessions were delivered, and the targeted compliance rate was 85%. Secondary objectives measured treatment-related toxicities and the effect of ALTENS on overall radiation-induced xerostomia burden using the University of Michigan Xerostomia-Related Quality of Life Scale (XeQOLS). RESULTS: Of 48 accrued patients, 47 were evaluable. The median age was 60 years, 84% of patients were men, 70% completed RT ± C for >12 months, and 21% had previously received pilocarpine. Thirty-four patients completed all 24 ALTENS sessions, 9 patients completed 20 to 23 sessions, and 1 patient completed 19 sessions, representing a 94% total compliance rate. Six-month XeQOLS scores were available for 35 patients and indicated that 30 patients (86%) achieved a positive treatment response with a mean ± standard deviation reduction of 35.9% ± 36.1%. Five patients developed grade 1 or 2 gastrointestinal toxicity, and 1 had a grade 1 pain event. CONCLUSIONS: The current results indicated that ALTENS treatment for radiation-induced xerostomia can be delivered uniformly in a cooperative, multicenter setting and produces possible beneficial treatment response. Given these results, the phase 3 component of this study was initiated.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Pilocarpina/uso terapêutico , Lesões por Radiação/terapia , Estimulação Elétrica Nervosa Transcutânea/métodos , Xerostomia/terapia , Acupuntura/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Radioterapia/efeitos adversos , Estimulação Elétrica Nervosa Transcutânea/efeitos adversos , Xerostomia/etiologia , Xerostomia/psicologia , Adulto Jovem
5.
J Sex Med ; 8(4): 1228-38, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21235716

RESUMO

INTRODUCTION: Erectile dysfunction (ED) may be the most commonly observed adverse event (AE) associated with the combination of radiation therapy (RT) and androgen deprivation therapy (ADT). A significant number of men are trying phosphodiesterase type 5 inhibitors (PDE5s) such as sildenafil to treat ED, yet sildenafil studies to date shed little light on the response to ED after ADT. AIM: The purpose of this trial was to evaluate sildenafil in the treatment of ED in prostate cancer patients previously treated with external beam RT and neoadjuvant and concurrent ADT. METHODS: In this randomized, double-blinded crossover trial, eligible patients received RT/ADT for intermediate risk prostate cancer and currently had ED as defined by the International Index of Erectile Function (IIEF). Patients were randomized to 12 weeks of sildenafil or placebo followed by 1 week of no treatment then 12 weeks of the alternative. Treatment differences were evaluated using a marginal model for binary crossover data. MAIN OUTCOME MEASURES: The primary end point was improved erectile function, as measured by the IIEF. RESULTS: The study accrued 115 patients and 61 (55%) completed all three IIEF assessments. Sildenafil effect was significant (P = 0.009) with a difference in probabilities of erectile response of 0.17 (95% confidence interval: 0.06, 0.29), and 0.21 (0.06, 0.38) for patients receiving ≤ 120 days of ADT. However, as few as 21% of patients had a treatment-specific response, only improving during sildenafil but not during the placebo phase. CONCLUSIONS: This is the first controlled trial to suggest a positive sildenafil response for ED treatment in patients previously treated with RT/ADT, however, only a minority of patients responded to treatment. ADT duration may be associated with response and requires further study. The overall low response rate suggests the need for study of additional or preventative strategies for ED after RT/ADT for prostate cancer.


Assuntos
Androgênios , Impotência Vasculogênica/tratamento farmacológico , Inibidores da Fosfodiesterase 5/uso terapêutico , Piperazinas/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Radioterapia/efeitos adversos , Sulfonas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Humanos , Impotência Vasculogênica/etiologia , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/complicações , Neoplasias da Próstata/radioterapia , Purinas/uso terapêutico , Medição de Risco , Autorrelato , Citrato de Sildenafila
6.
Am J Clin Oncol ; 41(4): 396-401, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-27100959

RESUMO

OBJECTIVES: The primary objective of NRG Oncology Radiation Therapy Oncology Group 0123 was to test the ability of the angiotensin-converting enzyme inhibitor captopril to alter the incidence of pulmonary damage after radiation therapy for lung cancer; secondary objectives included analyzing pulmonary cytokine expression, quality of life, and the long-term effects of captopril. MATERIALS AND METHODS: Eligible patients included stage II-IIIB non-small cell lung cancer, stage I central non-small cell lung cancer, or limited-stage small cell. Patients who met eligibility for randomization at the end of radiotherapy received either captopril or standard care for 1 year. The captopril was to be escalated to 50 mg three times a day. Primary endpoint was incidence of grade 2+ radiation-induced pulmonary toxicity in the first year. RESULTS: Eighty-one patients were accrued between June 2003 and August 2007. Given the low accrual rate, the study was closed early. No significant safety issues were encountered. Eight patients were ineligible for registration or withdrew consent before randomization and 40 patients were not randomized postradiation. Major reasons for nonrandomization included patients' refusal and physician preference. Of the 33 randomized patients, 20 were analyzable (13 observation, 7 captopril). The incidence of grade 2+ pulmonary toxicity attributable to radiation therapy was 23% (3/13) in the observation arm and 14% (1/7) in the captopril arm. CONCLUSIONS: Despite significant resources and multiple amendments, NRG Oncology Radiation Therapy Oncology Group 0123 was unable to test the hypothesis that captopril mitigates radiation-induced pulmonary toxicity. It did show the safety of such an approach and the use of newer angiotensin-converting enzyme inhibitors started during radiotherapy may solve the accrual problems.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Captopril/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Lesões por Radiação/tratamento farmacológico , Pneumonite por Radiação/tratamento farmacológico , Radioterapia Conformacional/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Qualidade de Vida , Lesões por Radiação/etiologia , Pneumonite por Radiação/etiologia
7.
World J Oncol ; 2(4): 181-190, 2011 08.
Artigo em Inglês | MEDLINE | ID: mdl-29147245

RESUMO

Background: The objective of this study was to validate a simple predictive model for survival of patients with advanced cancer. Methods: Previous studies with training and validation datasets developed a model predicting survival of patients referred for palliative radiotherapy using three readily available factors: primary cancer site, site of metastases and Karnofsky performance score (KPS). This predictive model was used in the current study, where each factor was assigned a value proportional to its prognostic weight and the sum of the weighted scores for each patient was survival prediction score (SPS). Patients were also classified according to their number of risk factors (NRF). Three risk groups were established. The Radiation Therapy and Oncology Group (RTOG) 9714 data was used to provide an additional external validation set comprised of patients treated among multiple institutions with appropriate statistical tests. Results: The RTOG external validation set comprised of 908 patients treated at 66 different radiation facilities from 1998 to 2002. The SPS method classified all patients into the low-risk group. Based on the NRF, two distinct risk groups with significantly different survival estimates were identified. The ability to predict survival was similar to that of the training and previous validation datasets for both the SPS and NRF methods. Conclusions: The three variable NRF model is preferred because of its relative simplicity.

8.
Contemp Clin Trials ; 31(3): 221-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20215046

RESUMO

PURPOSE: Timely recruitment and retention of human subjects remains a leading problem in oncology clinical trials even among the national oncology clinical trial cooperative groups. The Radiation Therapy Oncology Group (RTOG) developed an exploratory survey to assess member attitudes, beliefs, and practices (ABPs) towards clinical trials that might influence patient accrual to clinical trials. METHODS: The survey was developed using Survey Monkey(c) and emailed to principal investigators (PIs) and research associates (RAs) at 267 RTOG member institutions. Survey items were selected based on a review of the literature. PI and RA responses were matched by institution to determine whether responses varied due to job responsibilities and/or institutional practices. Principal component analysis was used to achieve variable reduction in further describing respondents' ABPs. RESULTS: PIs and RAs reported similar recruitment concerns [kappa=0.55, 95% CI (0.51, 0.60)]. Five components related to recruitment concerns were identified: presentation of trials to patients, barriers and recruitment risks, staff involvement, access for underrepresented populations, and familial involvement (patient). Nearly one of four (24%) respondents perceived that patients did not understand what randomization means. Staff issues included nearly a third of respondents not having a formal mechanism at their institution for eligibility screening, and similarly, about one of three respondents felt that unrepresented patient populations would benefit from translated consent forms. CONCLUSIONS: Findings of this survey inform RTOG strategies for addressing opportunities for improvement, including clinician/patient education and a best practices tool box that in the future would include successful mechanisms for eligibility screening and recruitment.


Assuntos
Atitude do Pessoal de Saúde , Ensaios Clínicos como Assunto , Seleção de Pacientes , Médicos , Radioterapia (Especialidade) , Pesquisadores , Intervalos de Confiança , Estudos Transversais , Coleta de Dados/métodos , Feminino , Humanos , Masculino , Neoplasias/radioterapia , Análise de Componente Principal , Estatística como Assunto , Estados Unidos
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