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1.
J Safety Res ; 68: 119-129, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30876503

RESUMO

INTRODUCTION: The purpose of this research was to determine whether the influence of supervisory support for safety on safety consciousness is direct or indirect. Based in part on predictions from the Theory of Reasoned Action (TRA) and Social Cognitive Theory (SCT), we examined the extent to which belief (safety self-efficacy) and attitude (cavalier safety attitude) mediate the impact of supervisory support for safety on employee safety consciousness. METHOD: A survey of 995 employees was distributed across 24 work groups in an electric utility company, and sequential mediation modeling was used to determine indirect effects on safety consciousness. RESULTS: We found that the effect of supervisory support on safety consciousness was indirect, fully mediated through both efficacy and attitude in a sequential mediation model. Practical applications: Supervisors should be aware of and emphasize supportive behaviors and create welcoming conditions for employees to raise safety concerns. Furthermore, organizational programs pertaining to safety improvement need to consider how to develop positive beliefs regarding safety activity and attitudes and reduce negative ones.

2.
J Anaesthesiol Clin Pharmacol ; 34(3): 386-391, 2018 Jul-Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30386025

RESUMO

Background and Aims: Coughing and sore throat postoperatively are common clinical problems during general anesthesia which can be avoided by various methods including topicalization of airway with local anesthetics, endotracheal tube cuff (ETT) inflation with local anesthetics, use of intravenous drugs such as dexamethasone, maintaining ETT cuff pressure, intubation by an experienced anethesiologist, etc. The aims of the study were to compare postextubation coughing response, mean number of cuff deflations required intraoperatively, and postoperative airway morbidity in terms of sore throat (2 h and 18-24 h), hoarseness of voice, and dysphagia following inflation of ETT cuff with air, anesthetic gas mixture, saline, and 2% lignocaine during general anesthesia. Material and Methods: One hundred and four patients were randomized into 1 of 4 groups depending on whether air, anesthetic gas mixture, saline, or 2% lignocaine was used to inflate the cuff of ETT using computer-generated randomization table. Results: There was no significant difference in the postextubation cough response among the four groups. The mean number of times the ETT cuff was deflated was significantly in favor of liquid media comapred to gaseous media (P < 0.001). The incidence of sore throat at 2 h and at 18-24 h, hoarseness of voice, and dysphagia were comparable in all groups. Conclusion: ETT cuff inflation with air, anesthetic gas mixture, 2% lignocaine, and saline are comparable in terms of incidence of postextubation cough and postoperative airway morbidity symptoms such as sore throat, hoarseness of voice, and dysphagia.

3.
Sci Rep ; 8(1): 16558, 2018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30409993

RESUMO

Effective conservation planning needs to consider the threats of cropland expansion to biodiversity. We used Myanmar as a case study to devise a modeling framework to identify which Key Biodiversity Areas (KBAs) are most vulnerable to cropland expansion in a context of increasingly resolved armed conflict. We studied 13 major crops with the potential to expand into KBAs. We used mixed-effects models and an agricultural versus forest rent framework to model current land use and conversion of forests to cropland for each crop. We found that the current cropland distribution is explained by higher agricultural value, lower transportation costs and lower elevation. We also found that protected areas and socio-political instability are effective in slowing down deforestation with conflicts in Myanmar damaging farmland and displacing farmers elsewhere. Under plausible economic development and socio-political stability scenarios, the models forecast 48.5% of land to be converted. We identified export crops such as maize, and pigeon pea as key deforestation drivers. This cropland expansion would pose a major threat to Myanmar's freshwater KBAs. We highlight the importance of considering rapid land-use transitions in the tropics to devise robust conservation plans.

4.
J Surg Case Rep ; 2018(8): rjy190, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30151102

RESUMO

Merkel-cell carcinoma is a rare form of aggressive cutaneous cancer that is associated with a poor prognosis. Despite significant advances, its pathogenesis is still poorly understood, and treatment remains controversial. Timely diagnosis and early management is essential in improving survival rate. We present a case of a 63-year-old patient with a rapidly growing upper limb Merkel-cell carcinoma. It was treated with wide-local excision and adjuvant radiotherapy.

5.
J Anaesthesiol Clin Pharmacol ; 34(2): 188-192, 2018 Apr-Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30104826

RESUMO

Background and Aims: Laryngeal mask airway (LMA) CTrach™ and Airtraq® videolaryngoscopes are useful for endotracheal intubation in patients with limited cervical spine movements and other predicted difficult airways. We aimed to compare LMA CTrach™ and Airtraq® videolaryngoscopes as conduits for endotracheal intubation in patients with simulated limitation of cervical spine movements by manual in-line stabilization (MILS). Material and Methods: This was a prospective, randomized study including 50 patients undergoing elective surgeries under general anesthesia. Patients were assigned to undergo intubation using Airtraq® (n = 25) or LMA CTrach™ (n = 25) by an experienced anesthesiologist, while MILS was provided. Laryngoscopy and intubation were compared in terms of time taken to obtain optimal laryngeal view, successful intubation, total time, percentage of glottis opening (POGO) score, maneuvers required for optimal laryngeal view and alignment of endotracheal tube, and number of attempts and complications. An integrated score was calculated to classify the attempt as good, restricted, or poor. Results: Time taken to obtain optimal laryngeal view, successful intubation, and total time in both groups were comparable. POGO score >50% was seen in 25 and 21 patients in Groups A and C. Seventy-six percent and ninety-six percent in Groups A and C, respectively, had a good integrated score; 6% and 1% had restricted score; none had a poor score; and the difference between them was statistically significant (P = 0.042). Conclusions: LMA CTrach™ and Airtraq® are similar with respect to time taken for obtaining optimal laryngeal view, successful intubation, and total time when used for intubation in patients with simulated limitation of cervical spine movements.

6.
Psychoneuroendocrinology ; 88: 136-143, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29268182

RESUMO

Disturbed sleep is a core feature of posttraumatic stress disorder (PTSD), characterized in part by decreased delta power sleep that may result from stress-related alterations in corticotropin releasing factor (CRF), hypothalamic pituitary adrenal axis (HPA) regulation and glucocorticoid signaling. Overnight HPA axis response mediating sleep disturbances in men and women with PTSD was examined using a metyrapone challenge. Metyrapone blocks cortisol synthesis, removing negative feedback, and increases the release of hypothalamic CRF and pituitary adrenocorticotropic hormone (ACTH). Laboratory-based polysomnography was used to monitor the sleep of 66 medically healthy, medication-free men and pre-menopausal follicular phase women including 33 with chronic PTSD (16 women and 17 men) and 33 age- and sex-matched controls (14 women and 19 men) over 3 consecutive nights. Participants completed an overnight metyrapone challenge after an adaptation and baseline night of sleep and ACTH was obtained by repeated blood sampling. Metyrapone resulted in a greater increase in ACTH and greater decreases in cortisol and delta spectral power sleep in PTSD subjects compared to controls, and a greater increase in ACTH in women compared to men. There was no sex difference in metyrapone effects on delta power sleep, and no significant metyrapone by PTSD by sex interactions with either ACTH or delta power sleep. Regression analyses indicated that a greater increase in ACTH response was associated with a greater decrease in delta power sleep response in PTSD subjects, but no such relationship was found in controls. The PTSD group difference was similar in men and women. These results suggest that stress-related alterations of the HPA axis in PTSD may contribute to sleep difficulties. Therapeutics that target the HPA axis may offer promise as a potential future treatment for PTSD and related sleep difficulties.

7.
Conserv Biol ; 31(6): 1257-1270, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29030915

RESUMO

Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long-running civil war. With these transitions in mind, we used a horizon-scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land-tenure insecurity, large-scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure- and energy-project planning, and reforming land-tenure and environmental-protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Agricultura Florestal/legislação & jurisprudência , Florestas , Política , Biodiversidade , Mianmar
8.
J Arthroplasty ; 32(12): 3711-3717, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28739308

RESUMO

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is globally endemic and is a leading cause of surgical site infection (SSI). The purpose of this study was to evaluate the incidence of SSI in MRSA carriers undergoing elective hip or knee arthroplasty, who had confirmed eradication and to compare it with incidence of SSI in non-MRSA carriers. METHODS: This is a retrospective analysis of 6613 patients who underwent elective total hip arthroplasty (THA; n = 3347) and total knee arthroplasty (TKA; n = 3266) at our institution. A cohort of patients who were preoperatively colonized with MRSA was identified. We compared the infection rates with non-MRSA carriers. RESULTS: We had a colonization rate of 1.3% (83 patients). A total of 79 patients had confirmed eradication of carrier status before surgical intervention. Of these, 38 were THAs and 41 were TKAs. Five of 79 patients (6.32%; 95% confidence interval [CI]: 2.35%-14.79%) had "deep SSI" within 1 year of surgery. There were 2 MRSA infections in THAs (relative risk 4.46; 95% CI: 1.12-17.82). There were 2 MRSA and 1 methicillin-sensitive Staphylococcus aureus infections in TKAs (relative risk 5.61; 95% CI: 1.81-17.38). A significant statistical difference in infection rates from MRSA negative control group was noted, which had a deep sepsis rate of 1.17% in THAs and 1.3% in TKAs over the same period. CONCLUSION: In spite of a selective treatment program for carriers and confirmed eradication, there is still a significantly increased risk of SSI in MRSA-colonized patients undergoing hip or knee arthroplasties.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas/epidemiologia , Infecção da Ferida Cirúrgica/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Clorexidina/administração & dosagem , Desinfetantes/administração & dosagem , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mupirocina/administração & dosagem , Estudos Retrospectivos , Risco , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus , Infecção da Ferida Cirúrgica/microbiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Reino Unido/epidemiologia
9.
Sci Rep ; 7: 46594, 2017 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-28436455

RESUMO

Myanmar offers unique opportunities for both biodiversity conservation and foreign direct investment due to projected economic growth linked to natural resource exploitation. Industrial-scale development introduces new land uses into the landscape, with unknown repercussions for local communities and biodiversity conservation. We use participatory mapping of 31 communities, focus groups in 28 communities, and analyses of forest cover change during 2000-2010 using MODIS vegetation continuous fields images, to understand the social and environmental impacts of gold mining and agricultural concessions in Myanmar's Hukaung Valley (~21,800 km2). Local communities, particularly the poorest households, benefit from work and trade opportunities offered by gold mining and agricultural companies but continue to depend on forests for house construction materials, food, and income from the sale of forest resources. However, gold mining and agricultural concessions reduce tree cover, potentially reducing access to forest resources and further marginalizing these households. Our analyses do not provide evidence that long-term resident communities contributed to forest cover loss between 2000 and 2010. We argue that landscape management, which recognizes local community rights to customary community use areas, and appropriate zoning for commercial land uses and protected areas could contribute to both local livelihoods and protect biodiversity throughout Myanmar during economic growth.

10.
Sleep ; 40(1)2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28364476

RESUMO

Objectives: To determine the interaction of age and habitual sleep duration in predicting cognitive performance in a large sample of participants aged 15 to 89 years. Methods: This study is a cross-sectional analysis of performance data gathered between January 2012 and September 2013. First-time players (N = 512823) of three internet cognitive training games measuring processing speed, working memory, visuospatial memory, and arithmetic participated in the study. Results: Performance was based on a measure of speed and accuracy for each game. The relationship between performance and self-reported habitual sleep duration was examined in the sample as a whole and across 10-year age groups starting at age 15 and ending at 75 and older. Performance peaked at 7 h of sleep duration for all three games in the sample as a whole, and the decrements in performance for sleep durations greater than 7 h were either comparable or greater in the youngest as compared to the oldest age groups. Conclusions: These findings challenge the hypothesis that deteriorating cognitive performance with long sleep duration is driven by medical comorbidities associated with aging. Further, these data are consistent with an optimal dose model of sleep and suggest that the model for the homeostatic recovery of cognitive function as a function of sleep duration should incorporate a curvilinear decline with longer duration sleep, indicating that there may be a cost to increased sleep. Replication and further research is essential for clarifying the sleep duration-cognition relationship in youth and adults of all ages.


Assuntos
Envelhecimento , Cognição/fisiologia , Sono/fisiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Envelhecimento/psicologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato , Análise e Desempenho de Tarefas , Fatores de Tempo , Adulto Jovem
12.
Cancer ; 123(1): 107-113, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27584945

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) lacks estrogen, progesterone, and human epidermal growth factor receptor 2 (HER2)/neu receptors, and is aggressive and therapeutically challenging. Genetic ancestry testing is an emerging medical field. Mitochondrial DNA (mtDNA), which is distinct from nuclear DNA, is maternally inherited and allows for origin determination. Patients with TNBC tend to be younger and are more likely to be African American, making this an ideal disease for mtDNA exploration. To the authors' knowledge, the current study is the first to perform mtDNA for self-described African American, White, and Hispanic patients with TNBC to identify mtDNA patterns. METHODS: Patients with TNBC who were at any stage of therapy/survivorship were included. Self-reported ethnicity was confirmed at the time of the prospective buccal swab. Haplogroup prediction was performed on sequencing of hypervariable region 1. Using sequence similarity scores and lineage databases, sequence patterns were determined. Data regarding presentation and treatment, tumor features, and outcomes was collected. RESULTS: A total of 92 patients were included: 31 self-described African American, 31 White, and 30 Hispanic individuals. Hispanic patients were found to have the largest tumor size (4.5 cm; P = .01) and youngest age (41 years; P<.0001). Eight patients were BRCA1/2 mutation carriers. There were no differences noted among groups with regard to surgery, lymph node metastases, or survival. Analysis revealed Nigerian, Cameroon, or Sierra Leone ancestry and haplogroups A, U, H, or B to be the most common mtDNA patterns. Twelve discordances (13%) between mtDNA analysis and self-described ethnicity were identified among the 92 patients. The highest discordance (26%; 8 patients) was noted in self-described Hispanic patients: 3 had Nigerian ancestry, and 1 individual demonstrated haplogroup K mtDNA (Ashkenazi Jewish ancestry). CONCLUSIONS: Discordance between self-reported ethnicity and mtDNA analysis was identified in 13% of patients with TNBC. The identification of mtDNA patterns with a predisposition toward TNBC may allow for risk stratification. Cancer 2017;107-113. © 2016 American Cancer Society.


Assuntos
DNA Mitocondrial/genética , Neoplasias de Mama Triplo Negativas/genética , Adulto , Afro-Americanos/genética , Grupo com Ancestrais do Continente Africano/genética , Camarões , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Testes Genéticos/métodos , Genótipo , Hispano-Americanos/genética , Humanos , Metástase Linfática/genética , Pessoa de Meia-Idade , Estudos Prospectivos , Receptor ErbB-2/genética , Receptores Estrogênicos/genética
13.
Conserv Biol ; 30(5): 972-81, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27341537

RESUMO

Although deforestation and forest degradation have long been considered the most significant threats to tropical biodiversity, across Southeast Asia (Northeast India, Indochina, Sundaland, Philippines) substantial areas of natural habitat have few wild animals (>1 kg), bar a few hunting-tolerant species. To document hunting impacts on vertebrate populations regionally, we conducted an extensive literature review, including papers in local journals and reports of governmental and nongovernmental agencies. Evidence from multiple sites indicated animal populations declined precipitously across the region since approximately 1980, and many species are now extirpated from substantial portions of their former ranges. Hunting is by far the greatest immediate threat to the survival of most of the region's endangered vertebrates. Causes of recent overhunting include improved access to forests and markets, improved hunting technology, and escalating demand for wild meat, wildlife-derived medicinal products, and wild animals as pets. Although hunters often take common species, such as pigs or rats, for their own consumption, they take rarer species opportunistically and sell surplus meat and commercially valuable products. There is also widespread targeted hunting of high-value species. Consequently, as currently practiced, hunting cannot be considered sustainable anywhere in the region, and in most places enforcement of protected-area and protected-species legislation is weak. The international community's focus on cross-border trade fails to address overexploitation of wildlife because hunting and the sale of wild meat is largely a local issue and most of the harvest is consumed in villages, rural towns, and nearby cities. In addition to improved enforcement, efforts to engage hunters and manage wildlife populations through sustainable hunting practices are urgently needed. Unless there is a step change in efforts to reduce wildlife exploitation to sustainable levels, the region will likely lose most of its iconic species, and many others besides, within the next few years.


Assuntos
Conservação dos Recursos Naturais , Florestas , Animais , Ásia Sudeste , Espécies em Perigo de Extinção , Humanos , Índia , Filipinas , Ratos , Suínos , Clima Tropical
15.
Glob Chang Biol ; 22(2): 656-65, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26367139

RESUMO

Protected areas (PAs) are an essential tool for the conservation of biodiversity globally. Previous studies have focussed on the effectiveness of PAs and the design of optimal PA networks. However, not all PAs remain intact permanently; many PAs undergo downgrading, downsizing and/or degazettement (PADDD), a fact largely ignored until recently. The drivers of enacted PADDD events and the factors influencing its spatial occurrence are poorly understood, potentially undermining the efficacy of PAs and PA networks. Here we examine the spatial relationship between PADDD and economic, demographic and structural variables, using a 110-year data set of 342 enacted PADDD events across 44 countries in the tropics and subtropics. We find that the probability of an enacted PADDD event increases with the size of the PA and through a synergistic interaction between PA size and local population densities. Our results are robust to the under-reporting of enacted PADDD events that occur among smaller PAs and in regions with lower population density. We find an economic motive for PADDD events, given that the opportunity costs associated with larger PAs are higher, on average, than smaller PAs. Our findings suggest a need for conservation practitioners to better consider PA characteristics, as well as the social, economic and political context in which PAs are situated, to aid the creation of more efficient and sustainable PA networks. In particular, the dynamics of enacted PADDD events highlight the need to explicitly consider PA robustness as a core component of systematic conservation planning for PA networks.


Assuntos
Conservação dos Recursos Naturais , Agricultura , Altitude , Humanos , Densidade Demográfica , Clima Tropical
17.
Psychosom Med ; 77(4): 383-91, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25886830

RESUMO

OBJECTIVE: Posttraumatic stress disorder (PTSD) is associated with indicators of poor physical health and sleep disturbance. This study investigated the relationship between PTSD and metabolic risk factors and examined the role of sleep duration in medically healthy and medication-free adults. METHODS: Participants with PTSD (n = 44, mean age = 30.6 years) and control participants free of lifetime psychiatric history (n = 50, mean age = 30.3 years) recorded sleep using sleep diary for 10 nights and actigraphy for 7 nights. We assessed metabolic risk factors including fasting triglycerides, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein cholesterol, as well as abdominal fat using dual-energy x-ray absorptiometry. RESULTS: PTSD was associated with shorter sleep duration (based on self-report, not actigraphy) and higher metabolic risks (controlling for body fat percentage), including increased triglycerides (p = .03), total cholesterol (p < .001), LDL cholesterol (p = .006), very low density lipoprotein cholesterol (p = .002), and cholesterol/high-density lipoprotein ratio (p = .024). In addition, sleep duration was associated with metabolic risks in PTSD (significant correlations ranged from r = -0.20 to r = -0.40) but did not fully account for the association between PTSD and metabolic measures. CONCLUSIONS: Metabolic risk factors are associated with PTSD even in early adulthood, which highlights the need for early intervention. Future longitudinal research should assess whether sleep disturbance in PTSD is a mechanism that contributes to heightened metabolic risk to elucidate the pathway from PTSD to higher rates of medical disorders such as obesity, diabetes, and heart disease.


Assuntos
Doenças Metabólicas/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Adulto , Comorbidade , Feminino , Humanos , Masculino , Doenças Metabólicas/sangue , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
18.
J Clin Endocrinol Metab ; 100(6): 2434-42, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25825943

RESUMO

CONTEXT: Consumption of high-fructose diets promotes hepatic fatty acid synthesis (de novo lipogenesis [DNL]) and an atherogenic lipid profile. It is unclear whether these effects occur independent of positive energy balance and weight gain. OBJECTIVES: We compared the effects of a high-fructose, (25% of energy content) weight-maintaining diet to those of an isocaloric diet with the same macronutrient distribution but in which complex carbohydrate (CCHO) was substituted for fructose. DESIGN, SETTING, AND PARTICIPANTS: Eight healthy men were studied as inpatients for consecutive 9-day periods. Stable isotope tracers were used to measure fractional hepatic DNL and endogenous glucose production (EGP) and its suppression during a euglycemic-hyperinsulinemic clamp. Liver fat was measured by magnetic resonance spectroscopy. RESULTS: Weight remained stable. Regardless of the order in which the diets were fed, the high-fructose diet was associated with both higher DNL (average, 18.6 ± 1.4% vs 11.0 ± 1.4% for CCHO; P = .001) and higher liver fat (median, +137% of CCHO; P = .016) in all participants. Fasting EGP and insulin-mediated glucose disposal did not differ significantly, but EGP during hyperinsulinemia was greater (0.60 ± 0.07 vs 0.46 ± 0.06 mg/kg/min; P = .013) with the high-fructose diet, suggesting blunted suppression of EGP. CONCLUSION: Short-term high-fructose intake was associated with increased DNL and liver fat in healthy men fed weight-maintaining diets.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Carboidratos da Dieta/farmacologia , Frutose/farmacologia , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Tecido Adiposo/metabolismo , Adiposidade/efeitos dos fármacos , Adolescente , Adulto , Idoso , Glucose/metabolismo , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Cancer Med ; 4(4): 500-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25641925

RESUMO

Triple-negative breast cancer (TNBC) is an uncommon but aggressive subtype of breast cancer. Obesity has been associated with an increased risk of breast cancer and worse prognosis. Some studies suggest that obese patients are less likely to achieve pathologic complete response (pCR) to neoadjuvant chemotherapy (NCT) and experience worse overall survival. Ki-67 is a proliferation marker that correlates with tumor aggressiveness. The goal of this study was to examine the impact of weight change during NCT for TNBC on pathologic response and Ki-67 reduction. Retrospective review identified 173 TNBC patients treated between 2004 and 2011. Data were collected on patient demographics, pre- and post-NCT body mass index (BMI), Ki-67, and pCR. Data analysis was performed using the two-tailed Student's t-test, analysis of variance (ANOVA), and Fisher's exact test. Sixty-six patients met final study criteria. Forty-three patients lost weight during chemotherapy and 23 gained weight. Patients in the weight gain group were significantly younger (P = 0.0013). There was no significant difference between the two groups in terms of Ki-67 reduction (P = 0.98) or pCR (P = 0.58). When patients were separated into normal weight (BMI<25 kg/m(2) ), overweight (BMI ≥ 25 and <30 kg/m(2) ), and obese (BMI ≥ 30 kg/m(2) ), there was no significant difference in Ki-67 among those groups either before or after NCT. The degree of obesity did not have a significant impact on Ki-67 reduction. Weight change during NCT does not appear to correlate with Ki-67 change or achieving pCR in TNBC. This may reflect the nature of this subtype of breast cancer that is less responsive to the hormonal effects that adipose tissue exerts on cancer cell proliferation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal de Mama/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal de Mama/complicações , Terapia por Exercício , Feminino , Humanos , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Terapia Neoadjuvante , Obesidade/complicações , Obesidade/terapia , Projetos Piloto , Estudos Retrospectivos , Neoplasias de Mama Triplo Negativas/complicações , Ganho de Peso/fisiologia , Perda de Peso/fisiologia
20.
J Clin Endocrinol Metab ; 100(4): 1664-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25658017

RESUMO

CONTEXT: Short sleep duration is associated with an increased risk of type 2 diabetes. Subchronic sleep restriction (SR) causes insulin resistance, but the mechanisms and roles of specific tissues are unclear. OBJECTIVE: The purpose of this article was to determine whether subchronic SR altered (1) hepatic insulin sensitivity, (2) peripheral insulin sensitivity, and (3) substrate utilization. DESIGN: This was a randomized crossover study in which 14 subjects underwent 2 admissions separated by a washout period. Each admission had 2 acclimatization nights followed by 5 nights of either SR (4 hours time in bed) or normal sleep (8 hours time in bed). MAIN OUTCOME MEASURE/METHODS: Insulin sensitivity (measured by hyperinsulinemic-euglycemic clamp) and hepatic insulin sensitivity (measured by stable isotope techniques) were measured. In addition, we assayed stress hormone (24-hour urine free cortisol, metanephrine, and normetanephrine), nonesterified fatty acid (NEFA), and ß-hydroxybutyrate (ß-OH butyrate) levels. Resting energy expenditure (REE) and respiratory quotient (RQ) were measured by indirect calorimetry. RESULTS: Compared to normal sleep, whole-body insulin sensitivity decreased by 25% (P = .008) with SR and peripheral insulin sensitivity decreased by 29% (P = .003). Whereas hepatic insulin sensitivity (endogenous glucose production) did not change significantly, percent gluconeogenesis increased (P = .03). Stress hormones increased modestly (cortisol by 21%, P = .04; metanephrine by 8%, P = .014; normetanephrine by 18%, P = .002). Fasting NEFA and ß-OH butyrate levels increased substantially (62% and 55%, respectively). REE did not change (P = 0.98), but RQ decreased (0.81 ± .02 vs 0.75 ± 0.02, P = .045). CONCLUSION: Subchronic SR causes unique metabolic disturbances characterized by peripheral, but not hepatic, insulin resistance; this was associated with a robust increase in fasting NEFA levels (indicative of increased lipolysis), decreased RQ, and increased ß-OH butyrate levels (indicative of whole-body and hepatic fat oxidation, respectively). We postulate that elevated NEFA levels are partially responsible for the decrease in peripheral sensitivity and modulation of hepatic metabolism (ie, increase in gluconeogenesis without increase in endogenous glucose production). Elevated cortisol and metanephrine levels may contribute to insulin resistance by increasing lipolysis and NEFA levels.


Assuntos
Resistência à Insulina , Privação do Sono/metabolismo , Adulto , Doença Crônica , Estudos Cross-Over , Feminino , Glucose/metabolismo , Técnica Clamp de Glucose , Teste de Tolerância a Glucose , Humanos , Fígado/metabolismo , Masculino , Especificidade de Órgãos , Sono/fisiologia , Adulto Jovem
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