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1.
Lancet Diabetes Endocrinol ; 11(10): 743-754, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37696273

RESUMO

BACKGROUND: Reference intervals of thyroid-stimulating hormone (TSH) and free thyroxine (FT4) are statistically defined by the 2·5-97·5th percentiles, without accounting for potential risk of clinical outcomes. We aimed to define the optimal healthy ranges of TSH and FT4 based on the risk of cardiovascular disease and mortality. METHODS: This systematic review and individual participant data (IPD) meta-analysis identified eligible prospective cohorts through the Thyroid Studies Collaboration, supplemented with a systematic search via Embase, MEDLINE (Ovid), Web of science, the Cochrane Central Register of Controlled Trials, and Google Scholar from Jan 1, 2011, to Feb 12, 2017 with an updated search to Oct 13, 2022 (cohorts found in the second search were not included in the IPD). We included cohorts that collected TSH or FT4, and cardiovascular outcomes or mortality for adults (aged ≥18 years). We excluded cohorts that included solely pregnant women, individuals with overt thyroid diseases, and individuals with cardiovascular disease. We contacted the study investigators of eligible cohorts to provide IPD on demographics, TSH, FT4, thyroid peroxidase antibodies, history of cardiovascular disease and risk factors, medication use, cardiovascular disease events, cardiovascular disease mortality, and all-cause mortality. The primary outcome was a composite outcome including cardiovascular disease events (coronary heart disease, stroke, and heart failure) and all-cause mortality. Secondary outcomes were the separate assessment of cardiovascular disease events, all-cause mortality, and cardiovascular disease mortality. We performed one-step (cohort-stratified Cox models) and two-step (random-effects models) meta-analyses adjusting for age, sex, smoking, systolic blood pressure, diabetes, and total cholesterol. The study was registered with PROSPERO, CRD42017057576. FINDINGS: We identified 3935 studies, of which 53 cohorts fulfilled the inclusion criteria and 26 cohorts agreed to participate. We included IPD on 134 346 participants with a median age of 59 years (range 18-106) at baseline. There was a J-shaped association of FT4 with the composite outcome and secondary outcomes, with the 20th (median 13·5 pmol/L [IQR 11·2-13·9]) to 40th percentiles (median 14·8 pmol/L [12·3-15·0]) conveying the lowest risk. Compared with the 20-40th percentiles, the age-adjusted and sex-adjusted hazard ratio (HR) for FT4 in the 80-100th percentiles was 1·20 (95% CI 1·11-1·31) for the composite outcome, 1·34 (1·20-1·49) for all-cause mortality, 1·57 (1·31-1·89) for cardiovascular disease mortality, and 1·22 (1·11-1·33) for cardiovascular disease events. In individuals aged 70 years and older, the 10-year absolute risk of composite outcome increased over 5% for women with FT4 greater than the 85th percentile (median 17·6 pmol/L [IQR 15·0-18·3]), and men with FT4 greater than the 75th percentile (16·7 pmol/L [14·0-17·4]). Non-linear associations were identified for TSH, with the 60th (median 1·90 mIU/L [IQR 1·68-2·25]) to 80th percentiles (2·90 mIU/L [2·41-3·32]) associated with the lowest risk of cardiovascular disease and mortality. Compared with the 60-80th percentiles, the age-adjusted and sex-adjusted HR of TSH in the 0-20th percentiles was 1·07 (95% CI 1·02-1·12) for the composite outcome, 1·09 (1·05-1·14) for all-cause mortality, and 1·07 (0·99-1·16) for cardiovascular disease mortality. INTERPRETATION: There was a J-shaped association of FT4 with cardiovascular disease and mortality. Low concentrations of TSH were associated with a higher risk of all-cause mortality and cardiovascular disease mortality. The 20-40th percentiles of FT4 and the 60-80th percentiles of TSH could represent the optimal healthy ranges of thyroid function based on the risk of cardiovascular disease and mortality, with more than 5% increase of 10-year composite risk identified for FT4 greater than the 85th percentile in women and men older than 70 years. We propose a feasible approach to establish the optimal healthy ranges of thyroid function, allowing for better identification of individuals with a higher risk of thyroid-related outcomes. FUNDING: None.


Assuntos
Doenças Cardiovasculares , Glândula Tireoide , Masculino , Adulto , Humanos , Feminino , Gravidez , Idoso , Idoso de 80 Anos ou mais , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Glândula Tireoide/fisiologia , Testes de Função Tireóidea , Tiroxina , Estudos Prospectivos , Doenças Cardiovasculares/epidemiologia , Tireotropina
2.
J Nat Prod ; 86(6): 1620-1631, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37308446

RESUMO

Fungal metabolites represent an underutilized resource in the development of novel anticancer drugs. This review will focus on the promising fungal nephrotoxin orellanine, found in mushrooms including Cortinarius orellanus (Fools webcap). Emphasis will be placed on its historical significance, structural features, and associated toxicomechanics. Chromatographic methods for analysis of the compound and its metabolites, its synthesis, and chemotherapeutic potential are also discussed. Although orellanine's exceptional selectivity for proximal tubular cells is well documented, the mechanics of its toxicity in kidney tissue remains disputed. Here, the most commonly proposed hypotheses are detailed in the context of the molecule's structure, the symptoms seen following ingestion, and its characteristic prolonged latency period. Chromatographic analysis of orellanine and its related substances remains challenging, while biological evaluation of the compound is complicated by uncertainty regarding the role of active metabolites. This has limited efforts to structurally refine the molecule; despite numerous established methods for its synthesis, there is minimal published material on how orellanine's structure might be optimized for therapeutic use. Despite these obstacles, orellanine has generated promising data in preclinical studies of metastatic clear cell renal cell carcinoma, leading to the early 2022 announcement of phase I/II trials in humans.


Assuntos
Agaricales , Micotoxinas , Neoplasias , Humanos , Micotoxinas/análise , Neoplasias/tratamento farmacológico , 2,2'-Dipiridil/química , 2,2'-Dipiridil/metabolismo , 2,2'-Dipiridil/toxicidade , Agaricales/metabolismo
3.
Food Sci Nutr ; 11(4): 1634-1656, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37051359

RESUMO

Vitamin K1 (VitK1) and Vitamin K2 (VitK2), two important naturally occurring micronutrients in the VitK family, found, respectively, in green leafy plants and algae (VitK1) and animal and fermented foods (VitK2). The present review explores the multiple biological functions of VitK2 from recently published in vitro and in vivo studies, including promotion of osteogenesis, prevention of calcification, relief of menopausal symptoms, enhancement of mitochondrial energy release, hepato- and neuro-protective effects, and possible use in treatment of coronavirus disease. The mechanisms of action associated with these biological effects are also explored. Overall, the findings presented here suggest that VitK, especially VitK2, is an important nutrient family for the normal functioning of human health. It acts on almost all major body systems and directly or indirectly participates in and regulates hundreds of physiological or pathological processes. However, as biological and clinical data are still inconsistent and conflicting, more in-depth investigations are warranted to elucidate its potential as a therapeutic strategy to prevent and treat a range of disease conditions.

4.
J Endocr Soc ; 7(2): bvac187, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36578880

RESUMO

Context: The skeletal effects of vitamin D remain controversial and it is uncertain whether variation in serum 25-hydroxyvitamin D (25OHD) levels over time influences bone mineral density (BMD). Objective: We evaluated longitudinal stability of serum 25OHD and associations with changes in BMD in participants aged 46-70 years at baseline. Methods: We studied 3698 Busselton Healthy Ageing Study participants (2040 female) with serum 25OHD and dual-energy x-ray absorptiometry (DXA) BMD assessments at baseline and at ∼6 years follow-up. Restricted cubic splines were used to evaluate associations between changes in 25OHD and BMD. Results: Mean season-corrected serum 25OHD was 81.3 ± 22.7 and 78.8 ± 23.1 nmol/L at baseline and 6 years, respectively, and showed moderate correlation (intraclass correlation coefficient: 0.724). Significant predictors of change in 25OHD concentration (Δ25OHD) included baseline 25OHD, change in body mass index and vitamin D supplementation at follow-up. Greater decline in serum 25OHD over time was associated with significantly greater reduction in BMD at total hip and femoral neck, but the magnitude of the differences was small (estimated differences 0.004 g/cm2 and 0.005-0.007 g/cm2, respectively, for lowest quartile of Δ25OHD compared with higher quartiles, adjusted for sex, baseline BMD, 25OHD, and demographics). No significant associations between Δ25OHD and lumbar spine BMD were observed. Increase in 25OHD levels was not associated with change in BMD. Conclusions: In this predominantly vitamin D-replete middle-aged cohort, serum 25OHD showed moderate longitudinal stability. Declining serum 25OHD over time was associated with greater reduction in BMD at the total hip and femoral neck.

5.
Eur Radiol ; 32(4): 2437-2447, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34718844

RESUMO

OBJECTIVES: The goal of this study was to investigate the effects of TACE using Lipiodol, Oncozene™ drug-eluting embolics (DEEs), or LUMI™-DEEs alone, or combined with bicarbonate on the metabolic and immunological tumor microenvironment in a rabbit VX2 tumor model. METHODS: VX2 liver tumor-bearing rabbits were assigned to five groups. MRI and extracellular pH (pHe) mapping using Biosensor Imaging of Redundant Deviation in Shifts (BIRDS) were performed before and after intra-arterial therapy with conventional TACE (cTACE), DEE-TACE with Idarubicin-eluting Oncozene™-DEEs, or Doxorubicin-eluting LUMI™-DEEs, each with or without prior bicarbonate infusion, and in untreated rabbits or treated with intra-arterial bicarbonate only. Imaging results were validated with immunohistochemistry (IHC) staining of cell viability (PCNA, TUNEL) and immune response (HLA-DR, CD3). Statistical analysis was performed using Mann-Whitney U test. RESULTS: pHe mapping revealed that combining cTACE with prior bicarbonate infusion significantly increased tumor pHe compared to control (p = 0.0175) and cTACE alone (p = 0.0025). IHC staining revealed peritumoral accumulation of HLA-DR+ antigen-presenting cells and CD3 + T-lymphocytes in controls. cTACE-treated tumors showed reduced immune infiltration, which was restored through combination with bicarbonate. DEE-TACE with Oncozene™-DEEs induced moderate intratumoral and marked peritumoral infiltration, which was slightly reduced with bicarbonate. Addition of bicarbonate prior to LUMI™-beads enhanced peritumoral immune cell infiltration compared to LUMI™-beads alone and resulted in the strongest intratumoral immune cell infiltration across all treated groups. CONCLUSIONS: The choice of chemoembolic regimen for TACE strongly affects post-treatment TME pHe and the ability of immune cells to accumulate and infiltrate the tumor tissue. KEY POINTS: • Combining conventional transarterial chemotherapy with prior bicarbonate infusion increases the pHe towards a more physiological value (p = 0.0025). • Peritumoral infiltration and intratumoral accumulation patterns of antigen-presenting cells and T-lymphocytes after transarterial chemotherapy were dependent on the choice of the chemoembolic regimen. • Combination of intra-arterial treatment with Doxorubicin-eluting LUMI™-beads and bicarbonate infusion resulted in the strongest intratumoral presence of immune cells (positivity index of 0.47 for HLADR+-cells and 0.62 for CD3+-cells).


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica/métodos , Doxorrubicina , Óleo Etiodado , Neoplasias Hepáticas/patologia , Coelhos , Microambiente Tumoral
6.
BMC Public Health ; 21(1): 1539, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380465

RESUMO

BACKGROUND AND OBJECTIVE: Chronic medical conditions accumulate within individuals with age. However, knowledge concerning the trends, patterns and determinants of multimorbidity remains limited. This study assessed the prevalence and patterns of multimorbidity using extensive individual phenotyping in a general population of Australian middle-aged adults. METHODS: Participants (n = 5029, 55% female), born between 1946 and 1964 and attending the cross-sectional phase of the Busselton Healthy Ageing Study (BHAS) between 2010 and 2015, were studied. Prevalence of 21 chronic conditions was estimated using clinical measurement, validated instrument scores and/or self-reported doctor-diagnosis. Non-random patterns of multimorbidity were explored using observed/expected (O/E) prevalence ratios and latent class analysis (LCA). Variables associated with numbers of conditions and class of multimorbidity were investigated. RESULTS: The individual prevalence of 21 chronic conditions ranged from 2 to 54% and multimorbidity was common with 73% of the cohort having 2 or more chronic conditions. (mean ± SD 2.75 ± 1.84, median = 2.00, range 0-13). The prevalence of multimorbidity increased with age, obesity, physical inactivity, tobacco smoking and family history of asthma, diabetes, myocardial infarct or cancer. There were 13 pairs and 27 triplets of conditions identified with a prevalence > 1.5% and O/E > 1.5. Of the triplets, arthritis (> 50%), bowel disease (> 33%) and depression-anxiety (> 33%) were observed most commonly. LCA modelling identified 4 statistically and clinically distinct classes of multimorbidity labelled as: 1) "Healthy" (70%) with average of 1.95 conditions; 2) "Respiratory and Atopy" (11%, 3.65 conditions); 3) "Non-cardiometabolic" (14%, 4.77 conditions), and 4) "Cardiometabolic" (5%, 6.32 conditions). Predictors of multimorbidity class membership differed between classes and differed from predictors of number of co-occurring conditions. CONCLUSION: Multimorbidity is common among middle-aged adults from a general population. Some conditions associated with ageing such as arthritis, bowel disease and depression-anxiety co-occur in clinically distinct patterns and at higher prevalence than expected by chance. These findings may inform further studies into shared biological and environmental causes of co-occurring conditions of ageing. Recognition of distinct patterns of multimorbidity may aid in a holistic approach to care management in individuals presenting with multiple chronic conditions, while also guiding health resource allocation in ageing populations.


Assuntos
Envelhecimento Saudável , Multimorbidade , Adulto , Austrália/epidemiologia , Doença Crônica , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência
7.
Radiology ; 296(3): 575-583, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32633675

RESUMO

Background The immuno-metabolic interplay has gained interest for determining and targeting immunosuppressive tumor micro-environments that remain a barrier to current immuno-oncologic therapies in hepatocellular carcinoma. Purpose To develop molecular MRI tools to reveal resistance mechanisms to immuno-oncologic therapies caused by the immuno-metabolic interplay in a translational liver cancer model. Materials and Methods A total of 21 VX2 liver tumor-bearing New Zealand white rabbits were used between October 2018 and February 2020. Rabbits were divided into three groups. Group A (n = 3) underwent intra-arterial infusion of gadolinium 160 (160Gd)-labeled anti-human leukocyte antigen-DR isotope (HLA-DR) antibodies to detect antigen-presenting immune cells. Group B (n = 3) received rhodamine-conjugated superparamagnetic iron oxide nanoparticles (SPIONs) intravenously to detect macrophages. These six rabbits underwent 3-T MRI, including T1- and T2-weighted imaging, before and 24 hours after contrast material administration. Group C (n = 15) underwent extracellular pH mapping with use of MR spectroscopy. Of those 15 rabbits, six underwent conventional transarterial chemoembolization (TACE), four underwent conventional TACE with extracellular pH-buffering bicarbonate, and five served as untreated controls. MRI signal intensity distribution was validated by using immunohistochemistry staining of HLA-DR and CD11b, Prussian blue iron staining, fluorescence microscopy of rhodamine, and imaging mass cytometry (IMC) of gadolinium. Statistical analysis included Mann-Whitney U and Kruskal-Wallis tests. Results T1-weighted MRI with 160Gd-labeled antibodies revealed localized peritumoral ring enhancement, which corresponded to gadolinium distribution detected with IMC. T2-weighted MRI with SPIONs showed curvilinear signal intensity representing selective peritumoral deposition in macrophages. Extracellular pH-specific MR spectroscopy of untreated liver tumors showed acidosis (mean extracellular pH, 6.78 ± 0.09) compared with liver parenchyma (mean extracellular pH, 7.18 ± 0.03) (P = .008) and peritumoral immune cell exclusion. Normalization of tumor extracellular pH (mean, 6.96 ± 0.05; P = .02) using bicarbonate during TACE increased peri- and intratumoral immune cell infiltration (P = .002). Conclusion MRI in a rabbit liver tumor model was used to visualize resistance mechanisms mediated by the immuno-metabolic interplay that inform susceptibility and response to immuno-oncologic therapies, providing a therapeutic strategy to restore immune permissiveness in liver cancer. © RSNA, 2020 Online supplemental material is available for this article.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas Experimentais , Imageamento por Ressonância Magnética/métodos , Imagem Molecular/métodos , Animais , Anticorpos/administração & dosagem , Anticorpos/química , Anticorpos/metabolismo , Biomarcadores , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Meios de Contraste/administração & dosagem , Meios de Contraste/química , Meios de Contraste/farmacocinética , Gadolínio/administração & dosagem , Gadolínio/química , Gadolínio/farmacocinética , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Neoplasias Hepáticas Experimentais/imunologia , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/terapia , Masculino , Coelhos , Microambiente Tumoral
8.
Clin Cancer Res ; 26(2): 428-438, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31582517

RESUMO

PURPOSE: To establish magnetic resonance (MR)-based molecular imaging paradigms for the noninvasive monitoring of extracellular pH (pHe) as a functional surrogate biomarker for metabolic changes induced by locoregional therapy of liver cancer. EXPERIMENTAL DESIGN: Thirty-two VX2 tumor-bearing New Zealand white rabbits underwent longitudinal imaging on clinical 3T-MRI and CT scanners before and up to 2 weeks after complete conventional transarterial chemoembolization (cTACE) using ethiodized oil (lipiodol) and doxorubicin. MR-spectroscopic imaging (MRSI) was employed for pHe mapping. Multiparametric MRI and CT were performed to quantify tumor enhancement, diffusion, and lipiodol coverage of the tumor posttherapy. In addition, incomplete cTACE with reduced chemoembolic doses was applied to mimic undertreatment and exploit pHe mapping to detect viable tumor residuals. Imaging findings were correlated with histopathologic markers indicative of metabolic state (HIF-1α, GLUT-1, and LAMP-2) and viability (proliferating cell nuclear antigen and terminal deoxynucleotidyl-transferase dUTP nick-end labeling). RESULTS: Untreated VX2 tumors demonstrated a significantly lower pHe (6.80 ± 0.09) than liver parenchyma (7.19 ± 0.03, P < 0.001). Upregulation of HIF-1α, GLUT-1, and LAMP-2 confirmed a hyperglycolytic tumor phenotype and acidosis. A gradual tumor pHe increase toward normalization similar to parenchyma was revealed within 2 weeks after complete cTACE, which correlated with decreasing detectability of metabolic markers. In contrast, pHe mapping after incomplete cTACE indicated both acidic viable residuals and increased tumor pHe of treated regions. Multimodal imaging revealed durable tumor devascularization immediately after complete cTACE, gradually increasing necrosis, and sustained lipiodol coverage of the tumor. CONCLUSIONS: MRSI-based pHe mapping can serve as a longitudinal monitoring tool for viable tumors. As most liver tumors are hyperglycolytic creating microenvironmental acidosis, therapy-induced normalization of tumor pHe may be used as a functional biomarker for positive therapeutic outcome.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Biomarcadores Tumorais/análise , Glicólise , Neoplasias Hepáticas Experimentais/patologia , Imagem Molecular/métodos , Microambiente Tumoral , Animais , Doxorrubicina/administração & dosagem , Óleo Etiodado/administração & dosagem , Concentração de Íons de Hidrogênio , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/metabolismo , Imageamento por Ressonância Magnética/métodos , Masculino , Coelhos
9.
Biomed Pharmacother ; 109: 865-875, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30551540

RESUMO

Plant-derived polyphenols are known to have promising biological activities including antioxidant and antityrosinase and may be a potential candidate for anti-dermatoheliotic remedy. The present study was performed to investigate the polyphenolic contents of Mimosa pudica (MP) seed extract and its anti-dermatoheliotic potential using non-invasive biophysical techniques after developing a stable topical emulgel formulation. Moreover, its in-vitro cytotoxicity was also evaluated using normal Human keratinocytes (HaCat cells) to rule out any cellular incompatibility. The results revealed that MP seed extract, constituted with a number of polyphenolic compounds, has very good antioxidant and anti-tyrosinase potential. There were significant positive effects (p ≤ 0.05) invoked by its topical emulgel formulation on various dermatoheliotic associated skin parameters like erythema, melanin, elasticity, hydration, and sebum as compared to placebo. In the meantime, it was also found to be biocompatible and did not show any effect on HaCat cell viability and structure. In conclusion, the topical emulgel preparation loaded with MP seed extract could be a great strategy to deal with dematoheliosis.


Assuntos
Fármacos Dermatológicos/análise , Mimosa , Extratos Vegetais/análise , Polifenóis/análise , Pele/efeitos dos fármacos , Administração Tópica , Adulto , Células Cultivadas , Cromatografia Líquida de Alta Pressão/métodos , Fármacos Dermatológicos/administração & dosagem , Fármacos Dermatológicos/isolamento & purificação , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/patologia , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Polifenóis/administração & dosagem , Polifenóis/isolamento & purificação , Sementes , Método Simples-Cego , Pele/metabolismo , Pele/patologia , Dermatopatias/tratamento farmacológico , Dermatopatias/metabolismo , Dermatopatias/patologia , Adulto Jovem
10.
Respirology ; 23(6): 576-582, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29365367

RESUMO

BACKGROUND AND OBJECTIVE: The relationship between vitamin D and respiratory disease was examined by cross-sectional analysis of a large community-based sample. METHODS: Serum 25-hydroxyvitamin D (25OHD) and history of respiratory disease, symptoms (recorded by questionnaire) and spirometry were measured in 5011 adults aged 45-69 years. Adjustments were made for age, sex, season and smoking (Model A), plus body mass index (BMI) and physical activity level (Model B), plus history of chronic diseases (Model C). RESULTS: Mean (SD) age was 58 (SD 6) years with 45% males, 10% current smokers and 12% taking vitamin D supplements. The prevalence of 25OHD level <50 nmol/L was 8.0%. In all the three models, 25OHD <50 nmol/L was significantly associated with asthma (Model C: odds ratio (OR): 1.32; 95% CI: 1.00, 1.73), bronchitis (1.54; 1.17, 2.01), wheeze (1.37; 1.10, 1.71) and chest tightness (1.42; 1.10, 1.83). Participants with vitamin D level > 100 nmol/L had higher forced vital capacity (FVC) in all the three models (1.17% higher, compared with the 50-100 nmol/L group in Model C). CONCLUSION: Low levels of serum 25OHD were independently associated with asthma, bronchitis, wheeze and chest tightness after three levels of adjustment for potential confounders. Higher vitamin D levels were associated with higher levels of lung function.


Assuntos
Asma/epidemiologia , Bronquite/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitamina D/análogos & derivados , Idoso , Asma/fisiopatologia , Índice de Massa Corporal , Bronquite/fisiopatologia , Estudos Transversais , Suplementos Nutricionais , Exercício Físico , Feminino , Volume Expiratório Forçado , Envelhecimento Saudável , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Sons Respiratórios/fisiopatologia , Estações do Ano , Fumar/epidemiologia , Espirometria , Inquéritos e Questionários , Capacidade Vital , Vitamina D/sangue , Vitamina D/uso terapêutico , Deficiência de Vitamina D/sangue , Austrália Ocidental/epidemiologia
11.
Clin Endocrinol (Oxf) ; 88(4): 529-537, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29095527

RESUMO

Prognosis from differentiated thyroid cancer is worse when the disease becomes refractory to radioiodine. Until recently, treatment options have been limited to local therapies such as surgery and radiotherapy, but the recent availability of systemic therapies now provides some potential for disease control. Multitargeted kinase inhibitors (TKIs) including lenvatinib and sorafenib have been shown to improve progression-free survival in phase III clinical trials, but are also associated with a spectrum of adverse effects. Other TKIs have been utilized as "redifferentiation" agents, increasing sodium iodide symporter expression in metastases and thus restoring radioiodine avidity. Some patients whose disease progresses on initial TKI therapy will still respond to a different TKI and clinical trials currently in progress will clarify the best options for such patients. As these drugs are not inexpensive, care needs to be taken to minimize not only biological but also financial toxicity. In this review, we examine the basic biology of radioiodine refractory disease and discuss optimal treatment approaches, with specific focus on choice and timing of TKI treatment. This clinical field remains fluid, and directions for future research include exploring biomarkers and considering adjuvant TKI use in certain patient groups.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/terapia , Humanos , Inibidores de Proteínas Quinases/efeitos adversos , Falha de Tratamento
12.
J AOAC Int ; 100(5): 1337-1344, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28492140

RESUMO

The best management of vitamin D deficiency, defined as a 25-hydroxyvitamin D [(25(OH)D] level <50 nM, is unclear. Intramuscular (IM) injection of a large bolus of vitamin D (≥100 000 IU) is used, but its safety is uncertain. In 10 adults given an IM injection of 600 000IU vitamin D3, we measured at baseline and at 1, 2, 3, and 4 weeks postinjection the serum levels of vitamin D3, 25(OH)D3, 25(OH)D2, total 25(OH)D, 3-epi-25(OH)D3, and 24,25-dihydroxyvitamin D3 [24,25(OH)2D3] using a standardized LC with tandem MS (MS/MS) assay; serum levels of 25(OH)D using the Abbott ARCHITECT i2000 immunoassay; and markers of bone metabolism. Bone markers and 25(OH)D (immunoassay) were remeasured at 24 weeks. All participants had baseline total 25(OH)D levels >50 nM. Serum 25(OH)D levels increased at 3, 4, and 24 weeks postinjection, peaking at 4 weeks [mean ± SEM of 126 ± 7.9 nM (immunoassay) and 100 ± 5.5 nM (LC-MS/MS)] but generally remained <125 nM, the upper limit recommended by the U.S. Institute of Medicine. Serum 24,25(OH)2D3 levels increased at 3 and 4 weeks postinjection. Serum ionized calcium levels were higher than baseline at 1, 3, and 4 weeks postinjection but remained within the clinically normal range. Other biochemical parameters, including other vitamin D metabolites, plasma alkaline phosphatase, and parathyroid hormone levels, were unchanged. IM injection of a large bolus of vitamin D effectively increases serum 25(OH)D levels without evidence of metabolic abnormality.


Assuntos
Cálcio/sangue , Vitamina D/análogos & derivados , Vitaminas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Química do Sangue , Cromatografia Líquida , Feminino , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem , Vitamina D/administração & dosagem
13.
Med J Aust ; 205(4): 179-84, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27510349

RESUMO

Serum thyroid-stimulating hormone (TSH) testing is the best screening tool for thyroid dysfunction. When TSH levels are in the reference range, additional tests such as free thyroxine, free triiodothyronine or thyroid antibodies rarely add value, except in patients with pituitary disease, when TSH is unreliable. Overt hypothyroidism and subclinical hypothyroidism with TSH levels > 10 mU/L can be treated without further investigation. The health impact of subclinical hypothyroidism with mildly elevated levels of TSH (4-10 mU/L) remains uncertain, particularly in older people; treatment or observation are reasonable options. Thyroxine remains standard treatment for hypothyroidism, with optimal dosage determined by clinical response and serum TSH. Hyperthyroidism is commonly caused by Graves' disease, thyroiditis or toxic nodular goitre. The cause should be established before offering treatment. Radionuclide scanning is the imaging modality of choice. Positive TSH-receptor antibodies indicate Graves' disease. Thyroid ultrasound is indicated for assessment of palpable goitre and thyroid nodules. It is not part of routine assessment of hyperthyroidism or hypothyroidism. Overzealous use of ultrasound identifies clinically unimportant thyroid nodules and can lead to overdiagnosis of thyroid cancer. For thyroid nodules, the key investigation is ultrasound-guided fine needle aspiration biopsy, depending on size and sonographic appearance. Biopsy should not be performed routinely on small nodules < 1 cm. It remains controversial whether pregnant women should be screened for thyroid disease. Reference intervals for thyroid function tests during pregnancy are not well established, and it is uncertain whether thyroxine treatment for pregnant women with serum TSH levels between 2.5 and 4.0 mU/L is beneficial. Iodine supplementation is recommended during pregnancy.


Assuntos
Medicina Geral , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/terapia , Adulto , Idoso , Feminino , Humanos , Hipertireoidismo/sangue , Hipertireoidismo/diagnóstico , Hipertireoidismo/terapia , Hipotireoidismo/sangue , Hipotireoidismo/diagnóstico , Hipotireoidismo/terapia , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Gravidez , Valores de Referência , Doenças da Glândula Tireoide/sangue , Testes de Função Tireóidea , Tireotropina/sangue
14.
Lancet Respir Med ; 4(6): 473-526, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27185520

RESUMO

The burden of chronic obstructive pulmonary disease (COPD) in the USA continues to grow. Although progress has been made in the the development of diagnostics, therapeutics, and care guidelines, whether patients' quality of life is improved will ultimately depend on the actual implementation of care and an individual patient's access to that care. In this Commission, we summarise expert opinion from key stakeholders-patients, caregivers, and medical professionals, as well as representatives from health systems, insurance companies, and industry-to understand barriers to care delivery and propose potential solutions. Health care in the USA is delivered through a patchwork of provider networks, with a wide variation in access to care depending on a patient's insurance, geographical location, and socioeconomic status. Furthermore, Medicare's complicated coverage and reimbursement structure pose unique challenges for patients with chronic respiratory disease who might need access to several types of services. Throughout this Commission, recurring themes include poor guideline implementation among health-care providers and poor patient access to key treatments such as affordable maintenance drugs and pulmonary rehabilitation. Although much attention has recently been focused on the reduction of hospital readmissions for COPD exacerbations, health systems in the USA struggle to meet these goals, and methods to reduce readmissions have not been proven. There are no easy solutions, but engaging patients and innovative thinkers in the development of solutions is crucial. Financial incentives might be important in raising engagement of providers and health systems. Lowering co-pays for maintenance drugs could result in improved adherence and, ultimately, decreased overall health-care spending. Given the substantial geographical diversity, health systems will need to find their own solutions to improve care coordination and integration, until better data for interventions that are universally effective become available.


Assuntos
Comitês Consultivos , Prestação Integrada de Cuidados de Saúde/tendências , Acessibilidade aos Serviços de Saúde/tendências , Guias de Prática Clínica como Assunto , Doença Pulmonar Obstrutiva Crônica/terapia , Prestação Integrada de Cuidados de Saúde/métodos , Fidelidade a Diretrizes/tendências , Humanos , Estados Unidos
15.
Pediatrics ; 135(1): e167-73, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25511121

RESUMO

Birth cohort studies provide an invaluable resource for studies of the influence of the fetal environment on health in later life. It is uncertain to what extent maternal vitamin D status influences fetal development. Using an unselected community-based cohort of 901 mother-offspring pairs (the Western Australian Pregnancy Cohort [Raine] Study), we examined the relationship between maternal vitamin D deficiency at 18 weeks' pregnancy and long-term health outcomes of offspring who were born in Perth, Western Australia (32° South), in 1989-1991. Vitamin D deficiency (serum 25-hydroxyvitamin D [25(OH)D] <50 nmol/L) was present in 36% (323 of 901) of the pregnant women. After adjusting for relevant covariates, maternal vitamin D deficiency during pregnancy was associated with impaired lung development in 6-year-old offspring, neurocognitive difficulties at age 10, increased risk of eating disorders in adolescence, and lower peak bone mass at 20 years. In summary, vitamin D may have an important, multifaceted role in the development of fetal lungs, brain, and bone. Experimental animal studies support an active contribution of vitamin D to organ development. Randomized controlled trials of vitamin D supplementation in pregnant women with long-term follow-up of offspring are urgently required to examine whether the correction of vitamin D deficiency in pregnant women is beneficial for their offspring and to determine the optimal level of maternal serum 25(OH)D for fetal development.


Assuntos
Deficiências do Desenvolvimento/epidemiologia , Desenvolvimento Fetal , Complicações na Gravidez , Deficiência de Vitamina D , Desenvolvimento Ósseo , Encéfalo/crescimento & desenvolvimento , Criança , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Pulmão/crescimento & desenvolvimento , Gravidez , Complicações na Gravidez/epidemiologia , Deficiência de Vitamina D/epidemiologia
16.
PLoS One ; 8(7): e69830, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23875003

RESUMO

Alzheimer's disease is a progressive neurodegenerative disease that entails impairments of memory, thinking and behavior and culminates into brain atrophy. Impaired glucose uptake (accumulating into energy deficits) and synaptic plasticity have been shown to be affected in the early stages of Alzheimer's disease. This study examines the ability of lipoic acid to increase brain glucose uptake and lead to improvements in synaptic plasticity on a triple transgenic mouse model of Alzheimer's disease (3xTg-AD) that shows progression of pathology as a function of age; two age groups: 6 months (young) and 12 months (old) were used in this study. 3xTg-AD mice fed 0.23% w/v lipoic acid in drinking water for 4 weeks showed an insulin mimetic effect that consisted of increased brain glucose uptake, activation of the insulin receptor substrate and of the PI3K/Akt signaling pathway. Lipoic acid supplementation led to important changes in synaptic function as shown by increased input/output (I/O) and long term potentiation (LTP) (measured by electrophysiology). Lipoic acid was more effective in stimulating an insulin-like effect and reversing the impaired synaptic plasticity in the old mice, wherein the impairment of insulin signaling and synaptic plasticity was more pronounced than those in young mice.


Assuntos
Fatores Etários , Doença de Alzheimer/fisiopatologia , Insulina/fisiologia , Mimetismo Molecular , Plasticidade Neuronal , Sinapses/fisiologia , Ácido Tióctico/fisiologia , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Glucose/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
17.
Clin Endocrinol (Oxf) ; 78(6): 852-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23581630

RESUMO

OBJECTIVE: Primary hyperparathyroidism and calcium supplementation have been linked to cardiovascular outcomes. The study objective was to examine plasma calcium as a predictor of cardiovascular disease in the general population, as results from previous cohort studies are conflicting. DESIGN, PARTICIPANTS AND MEASUREMENTS: Plasma calcium was measured in 4003 participants (aged 25-84 years) in the 1994/1995 Busselton Health Survey. Using a Cox proportional hazards model, we examined albumin-corrected calcium as a predictor of total mortality, cardiovascular mortality and cardiovascular events up to the end of 2010. RESULTS: At baseline, there were significant positive relationships between plasma calcium and each of body mass index, systolic and diastolic blood pressure, glucose and total cholesterol. During the follow-up period, 666 participants died (278 from cardiovascular disease) and 652 had incident cardiovascular events. After adjustment for age and sex, each additional 0.1 mm of albumin-corrected calcium at baseline was associated with a hazard ratio (HR) of 1.09 [95% confidence interval (CI) 0.99, 1.20; P = 0.062] for total mortality, 1.06 (95% CI 0.92, 1.23; P = 0.41) for cardiovascular mortality and 1.13 (95% CI 1.03, 1.24; P = 0.012) for cardiovascular events. These associations were attenuated by further adjustment for standard cardiovascular risk factors with HR 1.03 (95% CI 0.94, 1.14), 0.99 (95% CI 0.86, 1.16) and 1.05 (95% CI 0.95, 1.15), respectively. CONCLUSION: After adjustment for age and sex, plasma calcium is a predictor of cardiovascular events. This appears to be mediated by conventional cardiovascular risk factors, and calcium is not an independent predictor of cardiovascular disease.


Assuntos
Cálcio/sangue , Doenças Cardiovasculares/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/mortalidade , Estudos de Coortes , Humanos , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Austrália Ocidental/epidemiologia
18.
Proc Natl Acad Sci U S A ; 109(2): 610-5, 2012 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-22203976

RESUMO

The type 1 ryanodine receptor (RyR1) is expressed widely in the brain, with high levels in the cerebellum, hippocampus, and hypothalamus. We have shown that L-type Ca(2+) channels in terminals of hypothalamic magnocellular neurons are coupled to RyRs, as they are in skeletal muscle, allowing voltage-induced Ca(2+) release (VICaR) from internal Ca(2+) stores without Ca(2+) influx. Here we demonstrate that RyR1 plays a role in VICaR in nerve terminals. Furthermore, in heterozygotes from the Ryr1(I4895T/WT) (IT/+) mouse line, carrying a knock-in mutation corresponding to one that causes a severe form of human central core disease, VICaR is absent, demonstrating that type 1 RyR mediates VICaR and that these mice have a neuronal phenotype. The absence of VICaR was shown in two ways: first, depolarization in the absence of Ca(2+) influx elicited Ca(2+)syntillas (scintilla, spark, in a nerve terminal, a SYNaptic structure) in WT, but not in mutant terminals; second, in the presence of extracellular Ca(2+), IT/+ terminals showed a twofold decrease in global Ca(2+) transients, with no change in plasmalemmal Ca(2+) current. From these studies we draw two conclusions: (i) RyR1 plays a role in VICaR in hypothalamic nerve terminals; and (ii) a neuronal alteration accompanies the myopathy in IT/+ mice, and, possibly in humans carrying the corresponding RyR1 mutation.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Cálcio/metabolismo , Hipotálamo/citologia , Miopatia da Parte Central/genética , Neurônios/metabolismo , Terminações Pré-Sinápticas/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Animais , Fluorescência , Técnicas de Introdução de Genes , Hipotálamo/metabolismo , Camundongos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
19.
Behav Brain Res ; 220(2): 294-304, 2011 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-21335036

RESUMO

Juvenile Fischer 344 rats are known to be less playful than other inbred strains, although the neurobiological substrate(s) responsible for this phenotype is uncertain. In the present study, Fischer 344 rats were compared to the commonly used outbred Sprague-Dawley strain on several behavioral and physiological parameters in order to ascertain whether the lack of play may be related to compromised activity of brain dopamine (DA) systems. As expected, Fischer 344 rats were far less playful than Sprague-Dawley rats, with Fischer 344 rats less likely to initiate playful contacts with a playful partner and less likely to respond playfully to these contacts. We also found that Fischer 344 rats showed less of a startle response and greater pre-pulse inhibition (PPI), especially at higher pre-pulse intensities. The increase in PPI seen in the Fischer 344 rat could be due to reduced DA modulation of sensorimotor gating and neurochemical measures were consistent with Fischer 344 rats releasing less DA than Sprague-Dawley rats. Fast scan cyclic voltammetry (FSCV) revealed Fischer 344 rats had less evoked DA release in dorsal and ventral striatal brain slices and high-performance liquid chromatography revealed Fischer 344 rats to have less DA turnover in the striatum and prefrontal cortex. We also found DA-dependent forms of cortical plasticity were deficient in the striatum and prefrontal cortex of the Fischer 344 rat. Taken together, these data indicate that deficits in play and enhanced PPI of Fischer 344 rats may be due to reduced DA modulation of corticostriatal and mesolimbic/mesocortical circuits critical to the execution of these behaviors.


Assuntos
Comportamento Animal/fisiologia , Encéfalo/metabolismo , Dopamina/metabolismo , Jogos e Brinquedos , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Estimulação Acústica/métodos , Análise de Variância , Animais , Biofísica , Encéfalo/anatomia & histologia , Cromatografia Líquida de Alta Pressão/métodos , Corpo Estriado/citologia , Estimulação Elétrica/métodos , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Técnicas In Vitro , Inibição Psicológica , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Ratos , Ratos Endogâmicos F344/fisiologia , Ratos Sprague-Dawley , Reflexo de Sobressalto/fisiologia , Especificidade da Espécie
20.
Ann Biomed Eng ; 39(1): 260-76, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20945159

RESUMO

In this article, we present a point process method to assess dynamic baroreflex sensitivity (BRS) by estimating the baroreflex gain as focal component of a simplified closed-loop model of the cardiovascular system. Specifically, an inverse Gaussian probability distribution is used to model the heartbeat interval, whereas the instantaneous mean is identified by linear and bilinear bivariate regressions on both the previous R-R intervals (RR) and blood pressure (BP) beat-to-beat measures. The instantaneous baroreflex gain is estimated as the feedback branch of the loop with a point-process filter, while the RR-->BP feedforward transfer function representing heart contractility and vasculature effects is simultaneously estimated by a recursive least-squares filter. These two closed-loop gains provide a direct assessment of baroreflex control of heart rate (HR). In addition, the dynamic coherence, cross bispectrum, and their power ratio can also be estimated. All statistical indices provide a valuable quantitative assessment of the interaction between heartbeat dynamics and hemodynamics. To illustrate the application, we have applied the proposed point process model to experimental recordings from 11 healthy subjects in order to monitor cardiovascular regulation under propofol anesthesia. We present quantitative results during transient periods, as well as statistical analyses on steady-state epochs before and after propofol administration. Our findings validate the ability of the algorithm to provide a reliable and fast-tracking assessment of BRS, and show a clear overall reduction in baroreflex gain from the baseline period to the start of propofol anesthesia, confirming that instantaneous evaluation of arterial baroreflex control of HR may yield important implications in clinical practice, particularly during anesthesia and in postoperative care.


Assuntos
Barorreflexo/fisiologia , Biorretroalimentação Psicológica/fisiologia , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Modelos Cardiovasculares , Propofol/administração & dosagem , Anestésicos/administração & dosagem , Barorreflexo/efeitos dos fármacos , Biorretroalimentação Psicológica/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Simulação por Computador , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Injeções Intravenosas , Masculino , Modelos Estatísticos , Oscilometria/métodos , Adulto Jovem
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