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Bioassessment methods are critically needed to evaluate and monitor lake ecological condition. Aquatic macrophytes are good candidate indicators, but few lake bioassessment methods developed in North America use them. The few macrophyte bioassessment methods that do exist suffer from problems related to subjectivity and discernibility along disturbance gradients. We developed and tested a bioassessment approach for 462 north temperate lakes. The approach links macrophyte abundance to lake ecological condition via estimates of taxon-specific abundance-weighted tolerance to anthropogenic disturbance. Using variables related to eutrophication, urban development and agriculture, we calculated abundance-weighted tolerance ranges for 59 macrophyte taxa and clustered them according to their tolerance to anthropogenic disturbance. We also created a composite index of anthropogenic disturbance using 20 variables related to population density, land cover and water chemistry. We used a statistical approach to set ecological condition thresholds based on the observed abundance of sensitive, moderately tolerant and tolerant taxa in each lake. The resulting lake condition categories were usually stable across multiple survey events and largely agreed with condition rankings assigned using expert judgment. We suggest using this macrophyte bioassessment method for federal water quality reports, restoration and management on north temperate lakes.
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Eutrofização , Lagos , Ecologia , América do Norte , Qualidade da ÁguaRESUMO
Previous studies in head and neck squamous cell carcinoma (HNSCC) cell lines have revealed that the Ah receptor (AHR) plays a significant role in mediating the "aggressive" phenotype of these cells, which includes enhanced inflammatory signaling (e.g., IL6) and migratory potential. Here we sought to identify putative novel targets of the AHR associated with enhanced tumor invasiveness. Global gene expression analysis identified a number of genes that are repressed upon treatment of OSC-19 or HN30 cells with an AHR antagonist. Three growth factors were targets of AHR activity; amphiregulin (AREG), epiregulin (EREG), and platelet-derived growth factor A (PDGFA) were repressed by an AHR antagonist and further examined. Quantitative PCR analysis, ELISA, and siRNA-mediated knock down of AHR revealed an attenuation of basal and/or induced levels of expression of these growth factors in two HNSCC lines, following AHR antagonism. In silico analysis revealed that these growth factors possess dioxin-like response elements. Two other AHR ligands, 6-formylindolo[3,2-b]carbazole and benzo(a)pyrene (BP) also elicited similar responses. In conclusion, this study identified AREG, EREG, and PDGFA as growth factor targets of AHR activity associated with metastatic phenotype of HNSCC cells, suggesting that attenuation of AHR activity may be a therapeutic strategy.
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Fator de Crescimento Epidérmico/genética , Fator 2 de Crescimento de Fibroblastos/genética , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento Derivado de Plaquetas/genética , Receptores de Hidrocarboneto Arílico/fisiologia , Compostos Azo/farmacologia , Carcinoma de Células Escamosas , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/metabolismo , Epirregulina , Fator 2 de Crescimento de Fibroblastos/metabolismo , Expressão Gênica , Neoplasias de Cabeça e Pescoço , Humanos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Pirazóis/farmacologia , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
Background: Private sector literature demonstrates an association between perioperative transfusions and poor clinical outcomes. Hemostatic agents, surgeon training, and patient blood management programs (PBMPs) may mitigate perioperative bleeding. This study attempts to identify preoperative risk factors associated with perioperative transfusions in Veterans. Study Design and Methods: This study is a retrospective review of the prospectively maintained Veterans Affairs Surgical Quality Improvement Project database. Included patients were older than 18 years and underwent noncardiac surgery between April 1, 2016, and March 31, 2021. Data collected included demographics, surgery variables, preoperative clinical variables, postoperative outcomes, and perioperative transfusions. Cohorts were created based on transfusion status. Univariate and multivariate analyses were performed to characterize the similarities, differences, and potential predictors of perioperative transfusion. Results: Of 6108 patients included, 153 patients received perioperative transfusions. The risks for transfusion included older age, male sex, black race, smoking, and low body mass index (BMI). The highest percent of transfused patients underwent vascular (43.4%), orthopedic (22%), and general surgeries (20%). Transfusion increased risk for postoperative cerebral vascular accident (P = .041) and 30-day mortality (P < .001). Multivariate regression analysis revealed American Society of Anesthesiology class, chemotherapy within 30 days, increased age, tobacco smoking, and decreased BMI were predictive of perioperative transfusions. Discussion: Perioperative transfusions are associated with increased morbidity and mortality in the Veteran population. These retrospective data describe the complex relationships between perioperative transfusions and outcomes after noncardiac surgery. These results serve as a foundation to create predictive models and PBMP within the veteran population to decrease transfusion requirements and associated complications.
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Veteranos , Humanos , Masculino , Estados Unidos , Estudos Retrospectivos , Transfusão de Sangue , Fatores de Risco , Assistência Perioperatória/métodosRESUMO
Background: Perioperative blood transfusions are associated with increased morbidity and mortality. Each surgical specialty is associated with unique operative variables. Moreover, transfusion rates vary across specialty. This article seeks to elucidate variables both common and unique to surgical specialties. Materials and Methods: This study was a retrospective review of 5344 patients from the prospectively maintained Veterans Affairs Surgical Quality Improvement Project at a single-level 1A tertiary Veterans Affairs Medical Center. Data collected included demographic information, preoperative clinical variables, postoperative outcomes, and perioperative transfusion (within 72 hours of procedure). Patients were stratified based on whether they received a transfusion. Univariate and multivariate analyses were performed. P values <.05 were significant. Results: Of the 5344 patients included in the study, 153 required perioperative transfusion of at least one unit of packed red blood cells. Patients who underwent transfusion were more likely to be men, have an underlying bleeding disorder, and have more preoperative risk factors. Although unique risk factors were found within most specialties, there was no statistically significant difference in postoperative complications between surgical specialties. Patients requiring transfusion had higher rates of morbidity and mortality. Elevated preoperative hematocrit was significantly protective against requiring transfusion across most specialties. Conclusions: Specialty-based differences in transfusion requirement may be due to the proportion of older and more frail patients, hospital transfusion thresholds, and surgical complexity. Hematocrit, however, could be an effective target for mitigating cost and morbidity associated with transfusion. Preoperative hematocrit optimization through B12, folate, iron dosing, and erythropoietin supplementation could be a useful strategy.
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Background: Management of symptomatic pancreatic pseudocysts poses a unique challenge to minimally invasive surgeons. Despite the predominance of endoscopic management of pancreatic pseudocysts, the laparoscopic approach remains a critical skill in the armamentarium of surgeons. Methods: This report details a laparoscopic intragastric approach to create a pancreatic cystgastrostomy using intraoperative ultrasound and endoscopy. Conclusion: Laparoendoscopic techniques for pancreatic pseudocysts are still required in selective cases when endoscopic management is not available or fails. Using this technique provides patients with same clinical benefits of an endoscopic approach.
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Laparoscopia , Pseudocisto Pancreático , Drenagem/métodos , Endoscopia Gastrointestinal , Gastrostomia/métodos , Humanos , Laparoscopia/métodos , Pseudocisto Pancreático/diagnóstico por imagem , Pseudocisto Pancreático/cirurgiaRESUMO
Introduction: Sleeve gastrectomy engenders weight loss and improves comorbidities at 1 year postoperatively. A relationship has not been established between liver pathology and diabetic outcomes and weight loss following a sleeve gastrectomy. This study evaluates the association between liver pathology and both diabetic remission and weight loss in morbidly obese veterans. Methods: A prospective database of all patients undergoing sleeve gastrectomy with simultaneous liver biopsy at a Veterans Affairs Medical Center was analyzed from 2018 through 2020. The database included patient demographics, liver biopsy pathology, laboratory values, and antihyperglycemic medications. Patient outcomes at 12 months postoperatively were analyzed specifically for diabetic resolution and weight loss. Chi-square test and Fisher's exact test were used for categorical comparisons, and one-way analysis of variance test and two-tailed t-test were used for continuous variable comparisons. Multivariate linear regression models were created to assess the association between liver pathology and changes in body mass index (BMI) and diabetic status. A two-sided P-value of 0.05 indicated significance. Results: Of the 77 patients included in the study, 70.1% of patients achieved diabetic remission at 12 months. After condensing steatosis and fibrosis scores into low- and high-grade categories, patients with no hepatic disease had significantly lower BMI at 12 months postoperatively than patients with low- or high-grade hepatic disease (29.2 ± 3.6 kg/m2 versus 35.1 ± 4.0 kg/m2 versus 34.5 ± 3.7 kg/m2, respectively, P = .009). On multivariate linear regression model, low-grade overall hepatic disease (ß = 3.1 ± 1.5; P = .043) and preoperative oral glycemic medications (ß = 2.4 ± 1.0; P = .026) were associated with a significantly increased 12-month BMI. Also, Black or African American race compared with White race was associated with a significant decrease in postoperative BMI (ß = -1.9 ± 0.8; P = .023). Conclusions: Regardless of preexisting liver disease, most diabetic patients who undergo sleeve gastrectomy experience diabetic remission at 12 months postoperatively. Additionally, patients with no underlying liver disease lose more weight than those with low- or high-grade liver disease.
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Laparoscopia , Obesidade Mórbida , Índice de Massa Corporal , Gastrectomia , Humanos , Fígado , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Redução de PesoRESUMO
BACKGROUND: Historically, robotic surgery incurs longer operative times, higher costs, and nonsuperior outcomes compared with laparoscopic surgery. However, in areas of limited visibility and decreased accessibility such as the gastroesophageal junction, robotic platforms may improve visualization and facilitate dissection. This study compares 30-day outcomes between robotic-assisted foregut surgery (RAF) and laparoscopic-assisted foregut surgery in the Veterans Health Administration. STUDY DESIGN: This is a retrospective review of the Veterans Affairs Quality Improvement Program database. Patients undergoing laparoscopic-assisted foregut surgery and RAF were identified using CPT codes 43280, 43281, 43282, and robotic modifier S2900. Multivariable logistic regression and multivariable generalized linear models were used to analyze the independent association between surgical approach and outcomes of interest. RESULTS: A total of 9,355 veterans underwent minimally invasive fundoplication from 2008 to 2019. RAF was used in 5,392 cases (57.6%): 1.63% of cases in 2008 to 83.41% of cases in 2019. After adjusting for confounding covariates, relative to laparoscopic-assisted foregut surgery, RAF was significantly associated with decreased adjusted odds of pulmonary complications (adjusted odds ratio [aOR] 0.44, p < 0.001), acute renal failure (aOR 0.14, p = 0.046), venous thromboembolism (aOR 0.44, p = 0.009) and increased odds of infectious complications (aOR 1.60, p = 0.017). RAF was associated with an adjusted mean ± SD of 29 ± 2-minute shorter operative time (332 minutes vs 361 minutes; p < 0.001). CONCLUSIONS: Veterans undergoing RAF ascertained shorter operative times and reduced complications vs laparoscopy. As surgeons use the robotic platform, clinical outcomes and operative times continue to improve, particularly in operations where extra articulation in confined spaces is required.
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Laparoscopia , Procedimentos Cirúrgicos Robóticos , Humanos , Duração da Cirurgia , Complicações Pós-Operatórias/epidemiologia , Prevalência , Estudos Retrospectivos , Saúde dos VeteranosRESUMO
Nine-banded armadillos develop peripheral neuropathy after experimental Mycobacterium leprae infection that recapitulates human disease. We used an intracutaneous excision axotomy model to assess the effect of infection duration by M. leprae on axonal sprouting and Schwan cell density. 34 armadillos (17 naïve and 17 M. leprae-infected) underwent 3 mm skin biopsies to create an intracutaneous excision axotomy followed by a concentric 4-mm overlapping biopsy 3 and 12-months post M. leprae inoculation. A traditional distal leg biopsy was obtained at 15mo for intraepidermal nerve fiber (IENF) density. Serial skin sections were immunostained against a axons (PGP9.5, GAP43), and Schwann cells (p75, s100) to visualize regenerating nerves. Regenerative axons and proliferation of Schwann cells was measured and the rate of growth at each time point was assessed. Increasing anti-PGL antibody titers and intraneural M. leprae confirmed infection. 15mo following infection, there was evidence of axon loss with reduced distal leg IENF versus naïve armadillos, p < 0.05. This was associated with an increase in Schwann cell density (11,062 ± 2905 vs. 7561 ± 2715 cells/mm3, p < 0.01). Following excisional biopsy epidermal reinnervation increased monotonically at 30, 60 and 90 days; the regeneration rate was highest at 30 days, and decreased at 60 and 90 days. The reinnervation rate was highest among animals infected for 3mo vs those infected for 12mo or naïve animals (mean ± SD, 27.8 ± 7.2 vs.16.2 ± 5.8vs. 15.3 ± 6.5 mm/mm3, p < 0.05). The infected armadillos displayed a sustained Schwann cell proliferation across axotomy time points and duration of infection (3mo:182 ± 26, 12mo: 256 ± 126, naive: 139 ± 49 cells/day, p < 0.05). M. leprae infection is associated with sustained Schwann cell proliferation and distal limb nerve fiber loss. Rates of epidermal reinnervation were highest 3mo after infection and normalized by 12 mo of infection. We postulate that excess Schwann cell proliferation is the main pathogenic process and is deleterious to sensory axons. There is a compensatory initial increase in regeneration rates that may be an attempt to compensate for the injury, but it is not sustained and eventually followed by axon loss. Aberrant Schwann cell proliferation may be a novel therapeutic target to interrupt the pathogenic cascade of M. leprae.
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Hanseníase , Mycobacterium leprae , Animais , Tatus/microbiologia , Axotomia , Proliferação de Células , Hanseníase/complicações , Hanseníase/microbiologia , Hanseníase/patologia , Células de Schwann/patologiaRESUMO
Polyps in the upper and lower gastrointestinal tract can be premalignant or malignant lesions that can be treated endoscopically in early stages to prevent morbidity and more invasive procedures. This article critically reviews the techniques available and provides recommendations for endoscopic polypectomy.
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Endoscopia Gastrointestinal/métodos , Endoscopia Gastrointestinal/normas , Neoplasias Gastrointestinais/cirurgia , Pólipos/cirurgia , Endoscopia Gastrointestinal/instrumentação , Neoplasias Gastrointestinais/diagnóstico , Trato Gastrointestinal/anatomia & histologia , Trato Gastrointestinal/cirurgia , Humanos , Assistência Perioperatória/normas , Pólipos/diagnóstico , Guias de Prática Clínica como Assunto/normasRESUMO
BACKGROUND: Youth-onset type 2 diabetes (T2D) is a disease that is newly emerging and behavioral strategies for its prevention are limited. Interventions that target the lifestyle behaviors of adolescents, to improve poor dietary quality and reduce excessive sedentariness, promise to reduce the risk of developing T2D. Health coaching is effective for promoting healthy behaviors in patients who have chronic disease, but few experimental studies are in adolescents. This randomized controlled trial, in adolescents with prediabetes, will determine the effectiveness of a health coaching intervention to facilitate adoption of healthy diet and activity behaviors that delay or prevent development of T2D. METHODS/DESIGN: The Dietary Intervention for Glucose Tolerance In Teens (DIG IT) trial will involve an evaluation of a health coaching intervention in adolescents with prediabetes. Eligible participants will be randomized to receive 6months of health coaching or a single dietary consultation that is standard-of-care. The primary outcome will be 2-hour oral glucose tolerance test concentration. Secondary outcomes will include measures of glycemia and insulin action as well as dietary, physical activity and sedentary behaviors measured using an electronic food record, and by inclinometer. Data will be collected before and after the intervention (at 6months) and at 12months (to assess sustainability). DISCUSSION: This trial will determine whether a health coaching intervention, a personalized and low-cost approach to modify dietary and activity behaviors, is effective and sustainable for prevention of youth-onset T2D, relative to standard-of-care. Health coaching has the potential to be widely implemented in clinical or community settings.
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Diabetes Mellitus Tipo 2/prevenção & controle , Tutoria , Estado Pré-Diabético/dietoterapia , Adolescente , Comportamento do Adolescente , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Exercício Físico , Grupos Focais , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/metabolismo , Comportamentos Relacionados com a Saúde , Humanos , Estado Pré-Diabético/metabolismo , Comportamento Sedentário , Resultado do TratamentoRESUMO
OBJECTIVE: To determine the influence of dietary behaviors, assessed in a clinical setting, on measures of glycemia in overweight and obese adolescents. STUDY DESIGN: The study is a retrospective, cross-sectional chart review. Eligible participants were overweight youth (N = 146, age 9-21 years) who attended the Youth Diabetes Prevention Clinic in Indianapolis, IN. Glycemic status was assessed during a 2-hour oral glucose tolerance test (OGTT). In the Bright Futures Questionnaire, a recommended clinical tool for assessing unhealthy behaviors in youth, nutrition-specific questions were modified to quantify dietary habits. Associations between dietary habits and measures of glycemia were determined using multiple linear regression models. Skewed data are presented as geometric means and 95% confidence intervals. RESULTS: Of the 146 adolescents who were assessed [60% girls, age 13.7 years (13.3, 14.0), BMI 33.9 kg/m(2) (33.3, 34.5)], 40% were diagnosed with prediabetes. Higher intake of dessert foods was associated with increased glucose levels at 2 hours following the OGTT (ß = 0.23, p = 0.004), and higher intake of packaged snack foods was associated with elevated levels of hemoglobin A1c (ß = 0.04, p = 0.04), independent of adiposity. CONCLUSIONS: In obese youth, high intakes of dessert and packaged snack items were associated with elevated concentrations of glucose at 2 hours following the OGTT and hemoglobin A1c. Findings demonstrate the usefulness of a modified Bright Futures Questionnaire, used in a clinical setting, for identifying dietary behaviors associated with hyperglycemia in obese adolescents. ClinicalTrials.gov registration number: NCT02535169.
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Glicemia/metabolismo , Dieta/efeitos adversos , Comportamento Alimentar/psicologia , Hemoglobinas Glicadas/metabolismo , Obesidade Infantil/complicações , Estado Pré-Diabético/etiologia , Adiposidade , Adolescente , Criança , Estudos Transversais , Feminino , Teste de Tolerância a Glucose , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Indiana/epidemiologia , Masculino , Estado Nutricional , Obesidade Infantil/sangue , Obesidade Infantil/epidemiologia , Estado Pré-Diabético/sangue , Estado Pré-Diabético/prevenção & controle , Estudos Retrospectivos , Adulto JovemRESUMO
Colon cancer is the third most commonly diagnosed type of cancer in the United States. Lifestyle and dietary patterns influence colon cancer risk both positively and negatively. Among the dietary factors, several plant-derived compounds have been found to afford colon cancer protection. These compounds potentially influence all aspects of colonic cellular regulation and develop complex interrelationships with the colonic microbiome. Increasing understanding of the role of microorganisms in determining the colonic environment has led to awareness of this important interrelationship among dietary factors and the microbial population. Plant-derived polyphenols are active mediators of cellular events, target key carcinogenic pathways, and modulate colonic microbial populations. In turn, the colonic microorganisms metabolize dietary compounds and mediate cellular events. In addition, the role of estrogen receptors in colon cancer and the importance of dietary components that mediate estrogen receptor-ß are increasingly being discovered. Hence, dietary bioactive compounds and the intestinal microbiota create a complex milieu that directly affects the carcinogenic events of the colon. These relationships must be carefully characterized in future research to provide dietary recommendations that will reduce colon cancer risk.
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Neoplasias do Colo/microbiologia , Neoplasias do Colo/prevenção & controle , Suplementos Nutricionais/análise , Microbiota , Compostos Fitoquímicos/administração & dosagem , Animais , Neoplasias do Colo/epidemiologia , Humanos , Microbiota/efeitos dos fármacos , Fatores de RiscoRESUMO
BACKGROUND: We compared traditional pedagogical approaches such as time- and repetition-based methods with proficiency-based training. METHODS: Laparoscopic novices were assigned randomly to 1 of 3 training conditions. In experiment 1, participants in the time condition practiced for 60 minutes, participants in the repetition condition performed 5 practice trials, and participants in the proficiency condition trained until reaching a predetermined proficiency goal. In experiment 2, practice time and number of trials were equated across conditions. RESULTS: In experiment 1, participants in the proficiency-based training conditions outperformed participants in the other 2 conditions (P < .014); however, these participants trained longer (P < .001) and performed more repetitions (P < .001). In experiment 2, despite training for similar amounts of time and number of repetitions, participants in the proficiency condition outperformed their counterparts (P < .038). In both experiments, the standard deviations for the proficiency condition were smaller than the other conditions. CONCLUSIONS: Proficiency-based training results in trainees who perform uniformly and at a higher level than traditional training methodologies.