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1.
bioRxiv ; 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-37398030

RESUMO

Paradoxically, cigarette smoking is associated with a reduced risk of Parkinson's disease (PD). This led us to hypothesize that carbon monoxide (CO) levels, which are constitutively but modestly elevated in smokers, might contribute to neuroprotection. Using rodent models of PD based on α-synuclein (αSyn) accumulation and oxidative stress, we show that low-dose CO mitigates neurodegeneration and reduces αSyn pathology. Oral CO administration activated signaling cascades mediated by heme oxygenase-1 (HO-1), which have been implicated in limiting oxidative stress, and in promoting αSyn degradation, thereby conferring neuroprotection. Consistent with a neuroprotective effect of smoking, HO-1 levels in cerebrospinal fluid were higher in human smokers compared to nonsmokers. Moreover, in PD brain samples, HO-1 levels were higher in neurons without αSyn pathology. Thus, CO in rodent PD models reduces pathology and increases oxidative stress responses, phenocopying possible protective effects of smoking evident in PD patients. These data highlight the potential for low-dose CO modulated pathways to slow symptom onset and limit pathology in PD patients.

2.
J Nutr Health Aging ; 27(8): 609-616, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37702332

RESUMO

OBJECTIVES: Observational studies have suggested that a higher 25-hydroxyvitamin D concentration may be associated with longer telomere length; however, this has not been investigated in randomised controlled trials. We conducted an ancillary study within a randomised, double-blind, placebo-controlled trial of monthly vitamin D (the D-Health Trial) for the prevention of all-cause mortality, conducted from 2014 to 2020, to assess the effect of vitamin D supplementation on telomere length (measured as the telomere to single copy gene (T/S) ratio). DESIGN, SETTING, PARTICIPANTS, AND INTERVENTION: Participants were Australians aged 60-84 years and we randomly selected 1,519 D-Health participants (vitamin D: n=744; placebo: n=775) for this analysis. We used quantitative polymerase chain reaction to measure the relative telomere length (T/S ratio) at 4 or 5 years after randomisation. We compared the mean T/S ratio between the vitamin D and placebo groups to assess the effect of vitamin D supplementation on relative telomere length, using a linear regression model with adjustment for age, sex, and state which were used to stratify the randomisation. RESULTS: The mean T/S ratio was 0.70 for both groups (standard deviation 0.18 and 0.16 for the vitamin D and placebo groups respectively). The adjusted mean difference (vitamin D minus placebo) was -0.001 (95% CI -0.02 to 0.02). There was no effect modification by age, sex, body mass index, or predicted baseline 25-hydroxyvitamin D concentration. CONCLUSION: In conclusion, routinely supplementing older adults, who are largely vitamin D replete, with monthly doses of vitamin D is unlikely to influence telomere length.


Assuntos
Vitamina D , Vitaminas , Humanos , Idoso , Austrália , Vitaminas/farmacologia , Vitaminas/uso terapêutico , Calcifediol , Telômero , Suplementos Nutricionais , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Pharmacoecon Open ; 7(1): 111-120, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36253664

RESUMO

BACKGROUND: Little is known about the healthcare resource usage and costs for patients with cancer of unknown primary (CUP). OBJECTIVE: The aim of this study was to describe and quantify healthcare resource use and costs in Australia, 6 months prior to and after a diagnosis of CUP, and compare to those of women with ovarian cancer. METHODS: Individual-level data combining baseline surveys, clinical records and Medicare Benefits Schedule (MBS) claim records were analysed for 149 patients with CUP and 480 patients with ovarian cancer from two prospective cohort studies. MBS data were aggregated for the period 6 months prior to diagnosis date and 6 months after diagnosis. Data included doctor consultations, pathology, diagnostics, therapeutic procedures, imaging, allied health and medicines. Generalised linear models were used to evaluate the cost differences between CUP and ovarian cancer using gamma family and log link functions. Models were adjusted for age, employment, marital status, surgery, chemotherapy and number of comorbidities. RESULTS: The mean healthcare costs in the 6 months prior to diagnosis of CUP were Australian (AU) $3903 versus AU$1327 for ovarian cancer (adjusted cost ratio 2.94, 95% confidence interval [CI] 2.08-4.15). Mean healthcare costs 6 months post-diagnosis were higher for patients with CUP versus ovarian cancer (AU$20,339 vs AU$13,819, adjusted cost ratio 1.47, 95% CI 1.13-1.92). Higher costs for patients with CUP were driven by imaging (AU$1937 vs AU$1387), procedures (AU$5403 vs AU$2702) and prescribed medicines for all conditions (AU$10,111 vs AU$6717). CONCLUSIONS: Pre-diagnosis costs for patients with CUP are nearly triple those for ovarian cancer. Six months after diagnosis, healthcare costs for CUP remained higher than for ovarian cancer due to imaging, procedures and medicines.

4.
J Spec Oper Med ; 22(2): 37-41, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35639891

RESUMO

Nutrition is an essential component of Human Performance Optimization in Special Operations Forces (SOF) to enhance physical and mental performance, unit readiness, and mission success. Body composition is frequently used to monitor individual nutrition progress; however, using body fat percentage is limited both by the accuracy of the assessment method and its association with SOF relevant performance outcomes. Lower body fat and/or body mass index have generally, but not universally, been correlated with higher levels of physical performance, yet they poorly predict performance in military relevant tasks. As a complement to body fat, many performance dietitians in the SOF Human Performance Programs utilize the International Society for Advanced Kinanthropometry (ISAK) profile to assess body composition, proportionality, ratio of muscle to bone, and somatotype in combat Operators. Kinanthropometry is the study of human size, shape, proportion, composition, maturation, and gross function, and it is a helpful tool for monitoring nutrition and training progress in athletes and active individuals. The ISAK profile has been well established as an international method for talent identification, distinguishing characteristics between athletes across and within elite sports, and identifying predictors of sport performance that can be applied in the military setting. While some SOF dietitians are utilizing the ISAK profile, the challenge lies in translating sport data to military relevant outcomes. We present a series of four case studies demonstrating the utility of this method as a portable comprehensive assessment for cross-sectional and longitudinal body composition tracking in a military setting.


Assuntos
Cineantropometria , Esportes , Atletas , Composição Corporal/fisiologia , Estudos Transversais , Humanos
5.
J Environ Qual ; 51(3): 451-461, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35373848

RESUMO

Quantifying spatial and temporal fluxes of phosphorus (P) within and among agricultural production systems is critical for sustaining agricultural production while minimizing environmental impacts. To better understand P fluxes in agricultural landscapes, P-FLUX, a detailed and harmonized dataset of P inputs, outputs, and budgets, as well as estimated uncertainties for each P flux and budget, was developed. Data were collected from 24 research sites and 61 production systems through the Long-term Agroecosystem Research (LTAR) network and partner organizations spanning 22 U.S. states and 2 Canadian provinces. The objectives of this paper are to (a) present and provide a description of the P-FLUX dataset, (b) provide summary analyses of the agricultural production systems included in the dataset and the variability in P inputs and outputs across systems, and (c) provide details for accessing the dataset, dataset limitations, and an example of future use. P-FLUX includes information on select site characteristics (area, soil series), crop rotation, P inputs (P application rate, source, timing, placement, P in irrigation water, atmospheric deposition), P outputs (crop removal, hydrologic losses), P budgets (agronomic budget, overall budget), uncertainties associated with each flux and budget, and data sources. Phosphorus fluxes and budgets vary across agricultural production systems and are useful resources to improve P use efficiency and develop management strategies to mitigate environmental impacts of agricultural systems. P-FLUX is available for download through the USDA Ag Data Commons (https://doi.org/10.15482/USDA.ADC/1523365).


Assuntos
Agricultura , Fósforo , Canadá , Fósforo/análise , Solo , Estados Unidos , Água
6.
Clin Radiol ; 77(3): 231-235, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35022132

RESUMO

AIM: To follow-up previous work evaluating incidental findings of COVID-19 signs on computed tomography (CT) images of major trauma patients to include the second wave prior to any major effects from vaccines. MATERIALS AND METHODS: The study population included all patients admitted following major trauma between 1 January 2020 and 28 February 2021 with CT including the lungs (n=1776). Major trauma patients admitted pre-COVID-19 from alternate months from January 2019 to November 2019 comprised a control group (n=837). The assessing radiologists were blinded to the time period and used double reading in consensus to determine if the patient had signs of COVID-19. Lung appearances were classified as no evidence of COVID-19, minor signs, or major signs. RESULTS: The method successfully tracked the second wave of the COVID-19 pandemic in London. The estimated population affected by the disease based on those with major signs was similar to estimates of the proportion of the population in London with antibodies (around 30% by end February 2021) and the total of major and minor signs produced a much higher figure of 68%, which may include all those with both antibody and just T-cell responses. CONCLUSIONS: Incidental findings on CT from major trauma patients may provide a novel and sensitive way of tracking the virus. It is recommended that all major trauma units include a simple question on signs of COVID-19 to provide an early warning system for further waves.


Assuntos
COVID-19/epidemiologia , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ferimentos e Lesões/diagnóstico por imagem , Ferimentos e Lesões/epidemiologia , Idoso de 80 Anos ou mais , COVID-19/diagnóstico por imagem , Comorbidade , Feminino , Humanos , Achados Incidentais , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Prevalência , Reino Unido/epidemiologia
8.
J Appl Microbiol ; 131(2): 768-779, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33128819

RESUMO

AIMS: This study explores the microbial diversity of sources which may influence boat microbial communities. We investigated the impact of dock, air and water microbial communities on the hull, transom and bilge microbial communities over the span of 11 days. METHODS AND RESULTS: Using source tracking software, we investigated the extent to which each of our potential sources (air, water and dock) influenced the overall microbial community. This study concluded that the dock impacted 14-64% of the hull and transom microbial community. Micro-organisms from the water were shown to impact 5·6% the bilge microbial community but had minimal impact on hull and transom microbial communities. Micro-organisms from the air had minimal impact in all areas of the boat. CONCLUSIONS: Our results demonstrate that micro-organisms from sources other than water can influence the microbial community of a boat, suggesting that terrestrial micro-organisms can impact the boat microbial community. SIGNIFICANCE AND IMPACT OF THE STUDY: Outside of ballast tanks, microbial diversity on boats is largely unexplored. While ballast water is widely recognized as a route for dispersal of allochthonous micro-organisms, comparatively little is known about the microbial diversity on other areas of the boat. If the organisms on a boat originate from sources other than water, there is potential that terrestrial micro-organisms could be dispersed by shipping activity.


Assuntos
Microbiota , Navios , Microbiologia do Ar , Microbiologia da Água
9.
Gynecol Oncol ; 158(1): 47-53, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32381362

RESUMO

OBJECTIVES: To determine the impact of chemotherapy dose reductions and dose delays on progression-free survival (PFS) in women with ovarian cancer receiving first line chemotherapy in a real world prospective cohort study. METHODS: Patients with newly diagnosed epithelial ovarian (or peritoneal, fallopian tube) cancer enrolled in a national Australian prospective study, OPAL, who commenced three-weekly carboplatin (AUC 5 or 6) and paclitaxel 175 mg/m2 (CP) or carboplatin (AUC 5 or 6) and dose-dense weekly paclitaxel 80 mg/m2 (DD-CP) were eligible. Primary endpoint was PFS. RESULTS: 634 evaluable patients, 309 commenced CP and 325 DD-CP. Patient's age was similar in the two groups (median 62 years, range 21-79). All planned chemotherapy doses were completed by 66% vs 40% (p < 0.001) in the CP and DD-CP groups respectively. There was at least one treatment delay in 28% vs 58% (p < 0.001) in the CP and DD-CP groups, respectively, and 29% vs 49% (p < 0.001), respectively, required at least a 15% dose reduction for either carboplatin or paclitaxel. Median PFS was 29.2 [22.9, 43.8] and 21.5 [19.4, 23.1] months in the CP and DD-CP groups respectively. Adjusting for age, histology and FIGO stage PFS did not differ between treatment groups. Median PFS was similar in patients irrespective of dose reduction or dose delay. CONCLUSION: Patients receiving DD-CP required more dose reductions and delays due to haematological toxicities and lower completion rates than CP without significant difference in median PFS between CP and DD-CP. Median PFS was similar in patients irrespective of dose reduction or dose delay.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Epitelial do Ovário/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Carcinoma Epitelial do Ovário/cirurgia , Quimioterapia Adjuvante , Estudos de Coortes , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasias Ovarianas/cirurgia , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Intervalo Livre de Progressão , Estudos Prospectivos , Estudos Retrospectivos , Adulto Jovem
10.
Cancer Causes Control ; 31(2): 203-207, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31823169

RESUMO

PURPOSE: Chronic inflammation has been implicated in endometrial carcinogenesis yet the impact of potentially modifiable exposures that might affect inflammation, like diet, has been understudied. This study examined the association between the dietary inflammatory index (DII®), a literature-derived tool to assess the inflammatory potential of diet, and risk of developing, and survival after a diagnosis of endometrial cancer (EC). METHODS: This study included data from 1,287 women with EC and 1,435 population controls who participated in the Australian National Endometrial Cancer Study. Energy-adjusted DII (E-DII) scores were calculated from pre-diagnostic dietary intake obtained using a semi-quantitative food frequency questionnaire. Logistic regression was used to assess the association between E-DII scores and risk of EC and proportional-hazards models were used for survival analyses. RESULTS: Higher E-DII scores, reflecting a more pro-inflammatory diet, were not associated with risk of EC [adjusted odds ratio (OR) 0.98, 95% CI 0.77-1.24, p-trend = 0.7]. However, in stratified analyses, higher E-DII scores were associated with increased risk of EC among very obese (BMI 35 + kg/m2) women (OR 1.60, 95% CI 0.80-3.21, p-trend = 0.049, p-interaction = 0.045). After a median follow-up of 7.2 years there were 160 deaths, of which 110 (69%) were from EC. We found no association between E-DII score and survival. CONCLUSION: Greater inflammatory potential of pre-diagnostic diet was not associated with EC risk or survival. Secondary stratified analysis suggested greater inflammatory potential may be associated with EC risk in very obese women.


Assuntos
Dieta , Neoplasias do Endométrio/epidemiologia , Inflamação/epidemiologia , Obesidade/epidemiologia , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , Adulto Jovem
11.
Eur J Nutr ; 58(4): 1747-1756, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30027314

RESUMO

PURPOSE: Inflammation has been implicated in ovarian carcinogenesis. This study evaluated two dietary indices: the Dietary Inflammatory Index (DII®) and the Empirical Dietary Inflammatory Pattern (EDIP), in relation to risk of developing, and survival following, a diagnosis of ovarian cancer. METHODS: Data came from the Australian Ovarian Cancer Study (1375 cases, 1415 population controls). DII and EDIP scores were computed from dietary information obtained using a semiquantitative food-frequency questionnaire. Logistic regression was used to assess the association between DII and EDIP scores and risk of ovarian cancer and proportional hazards models were used for survival analysis. RESULTS: A high DII score, reflecting a more pro-inflammatory diet, was associated with a modest increased risk of ovarian cancer [odds ratio (OR) DII scoreQ4 vs.Q1 = 1.31, 95% CI 1.06-1.63, ptrend = 0.014]. Likewise a high EDIP score was associated with an increase in risk of ovarian cancer [OR EDIP scoreQ4 vs.Q1 = 1.39, 95% confidence interval (CI) 1.12-1.73, ptrend = 0.002]. We found no association between DII or EDIP score and overall or ovarian cancer-specific survival. CONCLUSION: In conclusion, our results suggest that a pro-inflammatory diet modestly increases the risk of developing ovarian cancer.


Assuntos
Dieta/efeitos adversos , Inflamação/epidemiologia , Neoplasias Ovarianas/epidemiologia , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Comorbidade , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Análise de Sobrevida , Adulto Jovem
12.
Eur J Nutr ; 58(4): 1757, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30267201

RESUMO

In the original publication of this article on page 6, paragraph "Discussion", line 4, 'In a U.S. population-based case-control study (n = 493 cases) Peres et al., reported a non-significant association between DII score and risk of developing ovarian cancer of similar magnitude (OR DII scoreQ4 vs. Q1 1.35, 95% CI 0.93-1.97) [20]'. It should read as 'In a U.S. population-based case-control study (n = 493 cases) Peres et al., reported a significant association between DII score and risk of developing ovarian cancer (OR DII scoreQ4 vs. Q1 1.72, 95% CI 1.18-2.51) [20]'.

13.
Ann Oncol ; 30(2): 310-316, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30566587

RESUMO

BACKGROUND: Regular use of aspirin has been associated with a reduced risk of cancer at several sites but the data for endometrial cancer are conflicting. Evidence regarding use of other analgesics is limited. PATIENTS AND METHODS: We pooled individual-level data from seven cohort and five case-control studies participating in the Epidemiology of Endometrial Cancer Consortium including 7120 women with endometrial cancer and 16 069 controls. For overall analyses, study-specific odds ratios (ORs) and 95% confidence intervals (CI) were estimated using logistic regression and combined using random-effects meta-analysis; for stratified analyses, we used mixed-effects logistic regression with study as a random effect. RESULTS: At least weekly use of aspirin and non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs) was associated with an approximately 15% reduced risk of endometrial cancer among both overweight and obese women (OR = 0.86 [95% CI 0.76-0.98] and 0.86 [95% CI 0.76-0.97], respectively, for aspirin; 0.87 [95% CI 0.76-1.00] and 0.84 [0.74-0.96], respectively, for non-aspirin NSAIDs). There was no association among women of normal weight (body mass index < 25 kg/m2, Pheterogeneity = 0.04 for aspirin, Pheterogeneity = 0.003 for NSAIDs). Among overweight and obese women, the inverse association with aspirin was stronger for use 2-6 times/week (OR = 0.81, 95% CI 0.68-0.96) than for daily use (0.91, 0.80-1.03), possibly because a high proportion of daily users use low-dose formulations. There was no clear association with use of acetaminophen. CONCLUSION: Our pooled analysis provides further evidence that use of standard-dose aspirin or other NSAIDs may reduce risk of endometrial cancer among overweight and obese women.


Assuntos
Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/efeitos adversos , Neoplasias do Endométrio/epidemiologia , Estudos de Casos e Controles , Estudos de Coortes , Neoplasias do Endométrio/induzido quimicamente , Feminino , Seguimentos , Humanos , Prognóstico , Fatores de Risco , Estados Unidos/epidemiologia
14.
Gynecol Oncol ; 150(1): 99-105, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29706522

RESUMO

OBJECTIVE: Although endometrial cancer (EC) is associated with relatively good survival rates overall, women diagnosed with high-risk subtypes have poor outcomes. We examined the relationship between lifestyle factors and subsequent all-cause, cancer-specific and non-cancer related survival. METHODS: In a cohort of 1359 Australian women diagnosed with incident EC between 2005 and 2007 pre-diagnostic information was collected by interview at recruitment. Clinical and survival information was abstracted from women's medical records, supplemented by linkage to the Australian National Death Index. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cause-specific survival (EC death vs. non-EC death) associated with each exposure, overall and by risk group (low-grade endometrioid vs. high-grade endometrioid and non-endometrioid). RESULTS: After a median follow-up of 7.1 years, 179 (13%) women had died, with 123 (69%) deaths from EC. As expected, elevated body mass index (BMI), diabetes and the presence of other co-morbidities were associated with a significantly increased risk of all-cause and non-cancer related death. Women with diabetes had higher cancer-specific mortality rates (HR 2.09, 95% CI 1.31-3.35), particularly those who had were not obese (HR 4.13, 95% CI 2.20-7.76). The presence of ≥2 other co-morbidities (excluding diabetes) was also associated with increased risk of cancer-specific mortality (HR 3.09, 95% CI 1.21-7.89). The patterns were generally similar for women with low-grade and high-grade endometrioid/non-endometrioid EC. CONCLUSION: Our findings demonstrate the importance of diabetes, other co-morbidities and obesity as negative predictors of mortality among women with EC but that the risks differ for cancer-specific and non-cancer related mortality.


Assuntos
Índice de Massa Corporal , Comorbidade/tendências , Diabetes Mellitus/mortalidade , Neoplasias do Endométrio/complicações , Neoplasias do Endométrio/mortalidade , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Análise de Sobrevida , Adulto Jovem
15.
Acta Physiol (Oxf) ; 220(2): 238-250, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27770485

RESUMO

AIM: Thyroid hormones regulate metabolic response. While triiodothyronine (T3) is usually considered to be the active form of thyroid hormone, one form of diiodothyronine (3,5-T2) exerts T3-like effects on energy consumption and lipid metabolism. 3,5-T2 also improves glucose tolerance in rats and 3,5-T2 levels correlate with fasting glucose in humans. Presently, however, little is known about mechanisms of 3,5-T2 effects on glucose metabolism. Here, we set out to compare effects of T3, 3,5-T2 and another form of T2 (3,3-T2) in a mouse model of diet-induced obesity and determined effects of T3 and 3,5-T2 on markers of classical insulin sensitization to understand how diiodothyronines influence blood glucose. METHODS: Cell- and protein-based assays of thyroid hormone action. Assays of metabolic parameters in mice. Analysis of transcript and protein levels in different tissues by qRT-PCR and Western blot. RESULTS: T3 and 3,5-T2 both reduce body weight, adiposity and body temperature despite increased food intake. 3,3'-T2 lacks these effects. T3 and 3,5-T2 reduce blood glucose levels, whereas 3,3'-T2 worsens glucose tolerance. Neither T3 nor 3,5-T2 affects markers of insulin sensitization in skeletal muscle or white adipose tissue (WAT), but both reduce hepatic GLUT2 glucose transporter levels and glucose output. T3 and 3,5-T2 also induce expression of mitochondrial uncoupling proteins (UCPs) 3 and 1 in skeletal muscle and WAT respectively. CONCLUSIONS: 3,5-T2 influences glucose metabolism in a manner that is distinct from insulin sensitization and involves reductions in hepatic glucose output and changes in energy utilization.


Assuntos
Glicemia/efeitos dos fármacos , Di-Iodotironinas/farmacologia , Resistência à Insulina , Animais , Dieta Hiperlipídica , Metabolismo Energético/efeitos dos fármacos , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade , Tri-Iodotironina/farmacologia
16.
Int J Obes (Lond) ; 40(11): 1776-1783, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27460601

RESUMO

BACKGROUND/OBJECTIVES: Our objective was to assess the sustained, low-dose and constant administration of the thyroid receptor-ß (TRß)-selective agonist GC-1 (sobetirome) from a novel nanochannel membrane device (NMD) for drug delivery. As it known to speed up metabolism, accomplish weight loss, improve cholesterol levels and possess anti-diabetic effects, GC-1 was steadily administered by our NMD, consisting of an implantable nanochannel membrane, as an alternative to conventional daily administration, which is subject to compliance issues in clinical settings. SUBJECTS/METHODS: Diet-induced obese C57BL/J6 male mice were fed a very high-fat diet (VHFD) and received NMD implants subcutaneously. Ten mice per group received capsules containing GC-1 or phosphate-buffered saline (control). Weight, lean and fat mass, as well as cholesterol, triglycerides, insulin and glucose, were monitored for 24 days. After treatment, plasma levels of thyroid-stimulating hormone (TSH) and thyroxine were compared. mRNA levels of a panel of thermogenic markers were examined using real-time PCR in white adipose tissue (WAT) and brown adipose tissue (BAT). Adipose tissue, liver and local inflammatory response to the implant were examined histologically. Pancreatic islet number and ß-cell area were assessed. RESULTS: GC-1 released from the NMD reversed VHFD-induced obesity and normalized serum cholesterol and glycemia. Significant reductions in body weight and fat mass were observed within 10 days, whereas reductions in serum cholesterol and glucose levels were seen within 7 days. The significant decrease in TSH was consistent with TRß selectivity for GC-1. Levels of transcript for Ucp1 and thermogenic genes PGC1a, Cidea, Dio2 and Cox5a showed significant upregulation in WAT in NMD-GC-1-treated mice, but decreased in BAT. Although mice treated by NMD-GC-1 showed a similar number of pancreatic islets, they exhibited significant increase in ß-cell area. CONCLUSIONS: Our data demonstrate that the NMD implant achieves steady administration of GC-1, offering an effective and tightly controlled molecular delivery system for treatment of obesity and metabolic disease, thereby addressing compliance.


Assuntos
Acetatos/administração & dosagem , Acetatos/uso terapêutico , Síndrome Metabólica/tratamento farmacológico , Fenóis/administração & dosagem , Fenóis/uso terapêutico , Receptores beta dos Hormônios Tireóideos/agonistas , Acetatos/farmacologia , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Masculino , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Terapia de Alvo Molecular , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Fenóis/farmacologia
17.
Contemp Clin Trials ; 48: 83-90, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27086041

RESUMO

BACKGROUND: Vitamin D, specifically serum 25(OH)D has been associated with mortality, cancer and multiple other health endpoints in observational studies, but there is a paucity of clinical trial evidence sufficient to determine the safety and effectiveness of population-wide supplementation. We have therefore launched the D-Health Trial, a randomized trial of vitamin D supplementation for prevention of mortality and cancer. Here we report the methods and describe the trial cohort. METHODS: The D-Health Trial is a randomized placebo-controlled trial, with planned intervention for 5years and a further 5years of passive follow-up through linkage with health and death registers. Participants aged 65-84years were recruited from the general population of Australia. The intervention is monthly oral doses of 60,000IU of cholecalciferol or matching placebo. The primary outcome is all-cause mortality. Secondary outcomes are total cancer incidence and colorectal cancer incidence. RESULTS: We recruited 21,315 participants to the trial between February 2014 and May 2015. The participants in the two arms of the trial were well-balanced at baseline. Comparison with Australian population statistics shows that the trial participants were less likely to report being in fair or poor health, to be current smokers or to have diabetes than the Australian population. However, the proportion overweight or with health conditions such as arthritis and angina was similar. CONCLUSIONS: Observational data cannot be considered sufficient to support interventions delivered at a population level. Large-scale randomized trials such as the D-Health Trial are needed to inform public health policy and practice.


Assuntos
Colecalciferol/uso terapêutico , Mortalidade , Neoplasias/prevenção & controle , Vitaminas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Causas de Morte , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Método Duplo-Cego , Humanos , Incidência , Masculino , Neoplasias/epidemiologia , Modelos de Riscos Proporcionais
18.
Br J Cancer ; 112(5): 925-33, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25688738

RESUMO

BACKGROUND: Nulliparity is an endometrial cancer risk factor, but whether or not this association is due to infertility is unclear. Although there are many underlying infertility causes, few studies have assessed risk relations by specific causes. METHODS: We conducted a pooled analysis of 8153 cases and 11 713 controls from 2 cohort and 12 case-control studies. All studies provided self-reported infertility and its causes, except for one study that relied on data from national registries. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Nulliparous women had an elevated endometrial cancer risk compared with parous women, even after adjusting for infertility (OR=1.76; 95% CI: 1.59-1.94). Women who reported infertility had an increased risk compared with those without infertility concerns, even after adjusting for nulliparity (OR=1.22; 95% CI: 1.13-1.33). Among women who reported infertility, none of the individual infertility causes were substantially related to endometrial cancer. CONCLUSIONS: Based on mainly self-reported infertility data that used study-specific definitions of infertility, nulliparity and infertility appeared to independently contribute to endometrial cancer risk. Understanding residual endometrial cancer risk related to infertility, its causes and its treatments may benefit from large studies involving detailed data on various infertility parameters.


Assuntos
Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/etiologia , Infertilidade Feminina/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Paridade , Fatores de Risco , Autorrelato
19.
Atherosclerosis ; 237(2): 544-54, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25463087

RESUMO

Thyroid hormone reduces plasma cholesterol and increases expression of low-density lipoprotein receptor (LDL-R) in liver, an effect mediated by thyroid receptor ß (TRß). The selective TRß modulator GC-1 also enhances several steps in reverse cholesterol transport and can decrease serum cholesterol independently of LDL-R. To test whether GC-1 reduces atherosclerosis and to determine which mechanisms are active, we treated ApoE deficient mice with atherogenic diet ± GC-1. GC-1 reduced cholesteryl esters in aorta after 20 weeks. Serum free and esterified cholesterol were reduced after 1 and 10 weeks, but not 20 weeks. Hepatic bile acid synthesis and LDL-R expression was elevated after 1, 10 and 20 weeks, without changes in hepatic de novo cholesterol synthesis. GC-1 increased faecal neutral sterols and reduced serum campesterol after 1 week, indicating reduced intestinal cholesterol absorption. After 20 weeks, GC-1 increased faecal bile acids, but not faecal neutral sterols. Hepatic scavenger receptor B1 (SR-B1) expression was decreased by GC-1. We conclude that GC-1 delays the onset of atherosclerosis in ApoE deficient mice. Since ApoE is needed for hepatic cholesterol reabsorption by LDL-R, this supports the idea that GC-1 reduces serum cholesterol independently of LDL-R by increasing hepatic bile acid synthesis. GC-1 lipid-lowering effects in ApoE deficient mice may also be partly due to reduced intestinal cholesterol absorption. Since reductions in serum cholesterol are reversed at longer times, these GC-1 dependent effects may not be enough for sustained cholesterol reduction in long term treatments.


Assuntos
Acetatos/farmacologia , Aterosclerose/tratamento farmacológico , Colesterol/sangue , Fenóis/farmacologia , Receptores beta dos Hormônios Tireóideos/metabolismo , Animais , Aorta/metabolismo , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Ácidos e Sais Biliares/química , Transporte Biológico , Colesterol/análogos & derivados , Colesterol/química , Colesterol/metabolismo , Modelos Animais de Doenças , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fitosteróis/sangue , Receptores de LDL/metabolismo , Esteróis/química , Fatores de Tempo
20.
Mol Endocrinol ; 28(4): 534-45, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24552590

RESUMO

Thyroid hormone receptors (TRs) are members of the nuclear receptor superfamily of ligand-activated transcription factors involved in cell differentiation, growth, and homeostasis. Although X-ray structures of many nuclear receptor ligand-binding domains (LBDs) reveal that the ligand binds within the hydrophobic core of the ligand-binding pocket, a few studies suggest the possibility of ligands binding to other sites. Here, we report a new x-ray crystallographic structure of TR-LBD that shows a second binding site for T3 and T4 located between H9, H10, and H11 of the TRα LBD surface. Statistical multiple sequence analysis, site-directed mutagenesis, and cell transactivation assays indicate that residues of the second binding site could be important for the TR function. We also conducted molecular dynamics simulations to investigate ligand mobility and ligand-protein interaction for T3 and T4 bound to this new TR surface-binding site. Extensive molecular dynamics simulations designed to compute ligand-protein dissociation constant indicate that the binding affinities to this surface site are of the order of the plasma and intracellular concentrations of the thyroid hormones, suggesting that ligands may bind to this new binding site under physiological conditions. Therefore, the second binding site could be useful as a new target site for drug design and could modulate selectively TR functions.


Assuntos
Receptores dos Hormônios Tireóideos/química , Receptores dos Hormônios Tireóideos/metabolismo , Hormônios Tireóideos/metabolismo , Aminoácidos/metabolismo , Sítios de Ligação , Linhagem Celular , Cristalografia por Raios X , Humanos , Ligantes , Simulação de Dinâmica Molecular , Estrutura Terciária de Proteína , Receptores dos Hormônios Tireóideos/genética , Relação Estrutura-Atividade , Ativação Transcricional
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