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1.
Eur Heart J Cardiovasc Pharmacother ; 9(5): 453-461, 2023 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-36921986

RESUMO

AIMS: To examine the dose dependency of diclofenac's cardiovascular risks. METHODS AND RESULTS: Using Danish health registries and the target trial emulation design, we conducted a series of 300 nationwide cohort studies during 1996-2020, each mimicking the strict design criteria of a clinical trial. Adults eligible for inclusion had no recent non-steroidal anti-inflammatory drug prescriptions, contraindications (gastrointestinal diseases, thrombocytopenia, or heart failure), or conditions with low adherence (dementia or psychiatric disease). Diclofenac initiators were compared to healthcare-seeking non-initiators and head-to-head using an approximated high dose of ≥150 mg/day vs. low dose of <150 mg/day. Cox regression was used to compute the incidence rate ratio (IRR) of major adverse cardiovascular events (MACE) within 30 days following initiation. We adjusted for age, sex, calendar period, comorbidity, comedication, and socioeconomic position. Compared with non-initiators (n = 3 789 617), diclofenac initiators (n = 1 894 834) had an approximately 50% increased rate of MACE (IRR 1.53, 95% confidence interval [CI]: 1.43-1.63), reflecting IRRs of 1.54 (95% CI: 1.40-1.69) for myocardial infarction, 1.29 (1.14-1.45) for ischaemic stroke, and 1.92 (1.71-2.16) for cardiac death. The risk increase was observed for most conditions with chronic pain, in particular headache (IRR 5.10, 95% CI: 1.46-17.85). The risk increase was similar for initiators of high- (IRR 1.55, 95% CI: 1.40-1.71) and low-dose diclofenac (IRR 1.52, 1.41-1.63), which was confirmed in a head-to-head analysis (IRR 1.01, 95% CI: 0.90-1.12). CONCLUSIONS: Initiators of high- and low-dose diclofenac had comparably increased cardiovascular risks. This finding provides evidence against the assumption that low-dose diclofenac is risk-neutral.


Assuntos
Isquemia Encefálica , Sistema Cardiovascular , Acidente Vascular Cerebral , Adulto , Humanos , Diclofenaco/efeitos adversos , Isquemia Encefálica/induzido quimicamente , Acidente Vascular Cerebral/induzido quimicamente , Anti-Inflamatórios não Esteroides/efeitos adversos
2.
Trials ; 23(1): 817, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36167555

RESUMO

BACKGROUND: Pseudomonas aeruginosa infection is seen in chronic pulmonary disease and is associated with exacerbations and poor long-term prognosis. However, evidence-based guidelines for the management and treatment of P. aeruginosa infection in chronic, non-cystic fibrosis (CF) pulmonary disease are lacking. The aim of this study is to investigate whether targeted antibiotic treatment against P. aeruginosa can reduce exacerbations and mortality in patients with chronic obstructive pulmonary disease (COPD), non-CF bronchiectasis, and asthma. METHODS: This study is an ongoing multicenter, randomized, controlled, open-label trial. A total of 150 patients with COPD, non-CF bronchiectasis or asthma, and P. aeruginosa-positive lower respiratory tract samples will be randomly assigned with a 1:1 ratio to either no antibiotic treatment or anti-pseudomonal antibiotic treatment with intravenous beta-lactam and oral ciprofloxacin for 14 days. The primary outcome, analyzed with two co-primary endpoints, is (i) time to prednisolone and/or antibiotic requiring exacerbation or death, in the primary or secondary health sector, within days 20-365 from study allocation and (ii) days alive and without exacerbation within days 20-365 from the study allocation. DISCUSSION: This trial will determine whether targeted antibiotics can benefit future patients with chronic, non-CF pulmonary disease and P. aeruginosa infection in terms of reduced morbidity and mortality, thus optimizing therapeutic approaches in this large group of chronic patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT03262142 . Registered on August 25, 2017.


Assuntos
Asma , Bronquiectasia , Doença Pulmonar Obstrutiva Crônica , Antibacterianos/efeitos adversos , Asma/complicações , Asma/diagnóstico , Asma/tratamento farmacológico , Bronquiectasia/diagnóstico , Bronquiectasia/tratamento farmacológico , Ciprofloxacina/efeitos adversos , Fibrose , Humanos , Prednisolona/uso terapêutico , Prognóstico , Pseudomonas aeruginosa , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , beta-Lactamas
3.
Drug Saf ; 45(9): 983-994, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35909207

RESUMO

INTRODUCTION: Diclofenac has increased cardiovascular risks, but its risk profile compared with other COX-2 inhibitors remains unknown. AIMS: The aim of this study was to compare the cardiovascular risks of diclofenac versus other older and newer COX-2 inhibitors (coxibs). METHODS: Using Danish nationwide health registries (1999-2020), we conducted a series of emulated trials (n = 264). Eligible adults had no recent NSAID prescriptions, contraindications or conditions with low adherence. We included initiators of diclofenac (n = 1,600,202), meloxicam (n = 10,903), etodolac (n = 238,538), celecoxib (n = 77,591), and etoricoxib (n = 12,122). We computed the adjusted intention-to-treat incidence rate ratio (aIRR) with 95% confidence interval (CI) of major adverse cardiovascular events (MACE) within 30 days of initiation (5562 events). RESULTS: MACE was 20% increased among initiators of diclofenac compared with other older COX-2 inhibitors (aIRR 1.19, 95% CI 1.10-1.28), driven by cardiac death (aIRR 1.57, 95% CI 1.21-2.03). The effect appeared strongest for women (aIRR 1.28, 95% CI 1.15-1.43), individuals with high baseline cardiovascular risk (aIRR 1.32, 95% CI 1.05-1.66), and when comparing high-dose diclofenac with low doses of the other older COX-2 inhibitors (aIRR 1.31, 95% CI 1.13-1.52). The results reflected increased rates compared with both meloxicam (aIRR 1.46, 95% CI 0.94-2.26) and etodolac (aIRR 1.18, 95% CI 1.09-1.28). Diclofenac initiators had similar increased rates of MACE compared with coxibs (aIRR 0.96, 95% CI 0.85-1.08), consistent for celecoxib (aIRR 1.02, 95% CI 0.88-1.19) and etoricoxib (aIRR 0.85, 95% CI 0.66-1.10). CONCLUSIONS: The increased cardiovascular risks associated with diclofenac initiation were higher than for other older COX-2 inhibitors (meloxicam/etodolac) and comparable to coxibs (celecoxib/etoricoxib).


Assuntos
Doenças Cardiovasculares , Inibidores de Ciclo-Oxigenase 2 , Adulto , Anti-Inflamatórios não Esteroides/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/epidemiologia , Celecoxib/efeitos adversos , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Diclofenaco/efeitos adversos , Etodolac , Etoricoxib/efeitos adversos , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Meloxicam/efeitos adversos , Fatores de Risco
4.
Elife ; 102021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473049

RESUMO

Plasmacytoid dendritic cells (pDCs) constitute a rare type of immune cell with multifaceted functions, but their potential use as a cell-based immunotherapy is challenged by the scarce cell numbers that can be extracted from blood. Here, we systematically investigate culture parameters for generating pDCs from hematopoietic stem and progenitor cells (HSPCs). Using optimized conditions combined with implementation of HSPC pre-expansion, we generate an average of 465 million HSPC-derived pDCs (HSPC-pDCs) starting from 100,000 cord blood-derived HSPCs. Furthermore, we demonstrate that such protocol allows HSPC-pDC generation from whole-blood HSPCs, and these cells display a pDC phenotype and function. Using GMP-compliant medium, we observe a remarkable loss of TLR7/9 responses, which is rescued by ascorbic acid supplementation. Ascorbic acid induces transcriptional signatures associated with pDC-specific innate immune pathways, suggesting an undescribed role of ascorbic acid for pDC functionality. This constitutes the first protocol for generating pDCs from whole blood and lays the foundation for investigating HSPC-pDCs for cell-based immunotherapy.


Assuntos
Ácido Ascórbico/farmacologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Células Dendríticas , Células-Tronco Hematopoéticas , Células Cultivadas , Meios de Cultura/química , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Imunoterapia
5.
Br J Anaesth ; 126(4): 872-880, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33455802

RESUMO

BACKGROUND: Ropivacaine is commonly used in local infiltration anaesthesia (LIA) as pain management after total knee arthroplasty (TKA). Although considered safe, no studies evaluated the pharmacokinetics of high-dose ropivacaine infiltration in simultaneous bilateral TKA. METHODS: We studied 13 patients undergoing unilateral and 15 undergoing bilateral TKA. Standard LIA technique was used with ropivacaine 0.2%, 200 ml (400 mg) injected peri-articularly in each knee. Free and total plasma concentrations of ropivacaine were measured within 24 h using liquid chromatography-mass spectrometry. A population pharmacokinetic model was built using non-linear mixed-effects models. RESULTS: Peak free ropivacaine concentration was 0.030 (0.017-0.071) µg ml-1 (mean [99% confidence interval]) vs 0.095 (0.047-0.208) µg ml-1, and peak total ropivacaine concentration was 0.756 (0.065-1.222) µg ml-1vs 1.695 (0.077-3.005) µg ml-1 for unilateral and bilateral TKA, respectively. The pharmacokinetics was ascribed a one-compartment model with first-order absorption. The main identified covariates were protein binding, allometrically scaled body weight on clearance and volume, and unilateral or bilateral surgery on volume. CONCLUSIONS: This is the first study to investigate the pharmacokinetics of free and total ropivacaine after unilateral and bilateral TKA. A population model was successfully built and peak free ropivacaine concentration stayed below previously proposed toxic thresholds in patients undergoing unilateral and bilateral TKA receiving LIA with high-dose ropivacaine. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04702282.


Assuntos
Anestesia Local/métodos , Anestésicos Locais/farmacocinética , Artroplastia do Joelho/efeitos adversos , Dor Pós-Operatória/metabolismo , Dor Pós-Operatória/prevenção & controle , Ropivacaina/farmacocinética , Idoso , Anestésicos Locais/administração & dosagem , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor/métodos , Estudos Prospectivos , Ropivacaina/administração & dosagem
6.
J Alzheimers Dis ; 79(4): 1601-1612, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33459639

RESUMO

BACKGROUND: It is controversial whether B12 deficiency causes dementia or B12 treatment can prevent dementia. OBJECTIVE: To assess associations between low plasma (P-)B12 levels, B12 treatment, and risk of Alzheimer's disease (AD; primary outcome) and all-cause or vascular dementia (secondary outcomes). METHODS: We conducted a population-based cohort study using Danish registry data to assess associations between low P-B12 levels, high-dose injection or oral B12 treatment, and risk of dementia (study period 2000-2013). The primary P-B12 cohort included patients with a first-time P-B12 measurement whose subsequent B12 treatment was recorded. The secondary B12 treatment cohort included patients with a first-time B12 prescription and P-B12 measurement within one year before this prescription. For both cohorts, patients with low P-B12 levels (<200 pmol/L) were propensity score-matched 1:1 with patients with normal levels (200-600 pmol/L). We used multivariable Cox regression to compute 0-15-year hazard ratios for dementia. RESULTS: For low P-B12 and normal P-B12 level groups, we included 53,089 patients in the primary P-B12 cohort and 13,656 patients in the secondary B12 treatment cohort. In the P-B12 cohort, hazard ratios for AD centered around one, regardless of follow-up period or treatment during follow-up. In the B12 treatment cohort, risk of AD was unaffected by low pre-treatment P-B12 levels, follow-up period and type of B12 treatment. Findings were similar for all-cause and vascular dementia. CONCLUSION: We found no associatio1n between low P-B12 levels and dementia. Associations were unaffected by B12 treatment. Results do not support routine screening for B12 deficiency in patients with suspected dementia.


Assuntos
Demência/sangue , Demência/epidemiologia , Suplementos Nutricionais , Deficiência de Vitamina B 12/epidemiologia , Vitamina B 12/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vitamina B 12/farmacologia , Deficiência de Vitamina B 12/complicações
7.
Endocrinology ; 161(8)2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32591825

RESUMO

Osteomalacia is a bone-demineralizing disease of adulthood, often caused by hypovitaminosis D. Current animal models of the disease mimic osteomalacia as a consequence of gastric bypass or toxic exposure to metals, but a relevant model of diet-induced osteomalacia is lacking. For that purpose, 7-month-old female Sprague Dawley rats were randomly assigned into 2 weight-stratified groups and maintained for 4 months on synthetic diets containing negligible or normal levels of vitamin D. The dietary regimen resulted in vitamin D deficiency as measured by 25-hydroxyvitamin D serum levels; however, hypovitaminosis D per se did not affect biomarkers of calcium metabolism and bone turnover, nor did it result in increased osteoid. Thus, vitamin D depletion through the diet was found to be insufficient to induce an osteomalacia-like phenotype in the adult rat. After 4 months, the phosphate content of the vitamin D-depleted diet had decreased to 0.16% (calcium:phosphorus ratio of 5.85), resulting in an osteomalacic-like condition (trabecular osteoid surface/bone surface constituted 33%; CI, 26-40). The diet change also affected both metabolic and bone turnover biomarkers, including significantly suppressing serum fibroblast growth factor 23. Furthermore, decreased dietary phosphate in a vitamin D-depleted diet led to microarchitectural changes of trabecular and cortical bone, lower bone mass density, lower bone mass content and decreased bone strength, all indicating reduced bone quality. Taken together, our results show that osteomalacia can be induced in the adult female rat by depleting vitamin D and lowering phosphate content in the diet.


Assuntos
Hipofosfatemia/complicações , Osteomalacia/etiologia , Deficiência de Vitamina D/complicações , Animais , Remodelação Óssea , Osso e Ossos/metabolismo , Calcificação Fisiológica , Cálcio/sangue , Cálcio/urina , Feminino , Hipofosfatemia/metabolismo , Hipofosfatemia/patologia , Osteomalacia/metabolismo , Osteomalacia/patologia , Fosfatos/sangue , Fosfatos/urina , Fósforo/sangue , Fósforo/urina , Ratos , Ratos Sprague-Dawley , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/metabolismo , Deficiência de Vitamina D/patologia
8.
Nephrol Dial Transplant ; 33(9): 1610-1620, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29177463

RESUMO

Background: Data on the true burden of hyperkalemia (HK) in patients with chronic kidney disease (CKD) in a real-world setting are scarce. Methods: The incidence rate of HK [first blood test with an elevated blood potassium level level >5.0 mmol/L] in primary or hospital care was assessed in a population-based cohort of all newly diagnosed CKD patients [second estimated glomerular filtration rate (eGFR) measurement <60 mL/min/1.73 m2 or hospital diagnosis] in northern Denmark. Risk factors and clinical outcomes were compared for CKD patients with HK and matched CKD patients without HK. Results: Of 157 766 patients with CKD, 28% experienced HK, for an overall HK incidence rate of 70/1000 person-years. Among patients with Stage 3A, 3B, 4 or 5 CKD, 9, 18, 31 and 42%, respectively, experienced HK within the first year. Important HK risk factors included diabetes {prevalence ratio [PR] 1.74 [95% confidence interval (CI) 1.69-1.79]}, heart failure [PR 2.31 (95% CI 2.23-2.40)] and use of angiotensin-converting enzyme inhibitors [PR 1.45 (95% CI 1.42-1.48)], potassium supplements [PR 1.59 (95% CI 1.55-1.62)] or spironolactone [PR 2.53 (95% CI 2.44-2.63)]. In CKD patients who developed HK, 34% had any acute hospitalization 6 months before the HK event, increasing to 57% 6 months after HK [before-after risk ratio 1.72 (95% CI 1.69-1.74)]. The 6-month mortality following HK was 26%, versus 6% in matched non-HK patients. Compared with non-HK patients, 6-month hazard ratios for any acute hospitalization in HK patients were 2.11-fold higher, including hazard ratios of 2.07 for cardiac diagnoses, 2.29 for ventricular arrhythmias, 3.26 for cardiac arrest, 4.77 for intensive care and 4.85 for death. Conclusions: More than one in four CKD patients develops HK. Patients with severe CKD, diabetes, heart failure or use of spironolactone are at high risk. HK is associated with severe clinical outcomes.


Assuntos
Diabetes Mellitus/fisiopatologia , Insuficiência Cardíaca/complicações , Hospitalização/estatística & dados numéricos , Hiperpotassemia/sangue , Potássio/sangue , Insuficiência Renal Crônica/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Taxa de Filtração Glomerular , Humanos , Hiperpotassemia/epidemiologia , Hiperpotassemia/etiologia , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Índice de Gravidade de Doença
9.
Pharmacoepidemiol Drug Saf ; 25(2): 188-95, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26676925

RESUMO

PURPOSE: Some studies have suggested that maternal acetaminophen use during pregnancy is associated with asthma in the offspring, and coffee consumption may modify the toxicity of acetaminophen. We aim to examine whether pregnancy maternal acetaminophen use increases the risk for offspring asthma, and whether such a potential association could be modified by maternal coffee consumption. METHODS: We included 63,652 live-born singletons enrolled in the Danish National Birth Cohort. Maternal acetaminophen use and coffee consumption during pregnancy were assessed prospectively via the enrolment questionnaire and three computer-assisted telephone interviews. Asthma cases were identified by using the Danish National Patient Register and the Danish National Prescription Registry. We estimated the hazard ratios (HRs) for asthma according to prenatal acetaminophen and coffee exposure using Cox proportional hazards regression model. RESULTS: After adjusting for potential confounders, acetaminophen use during pregnancy was associated with an increased risk of offspring asthma (HR = 1.16, 95% confidence interval (CI): 1.11-1.22). Coffee drinking during pregnancy was associated with a slightly decreased risk (HR = 0.94, 95%CI: 0.90-0.99). But there was no strong evidence of effect measure modification of acetaminophen use on offspring asthma by coffee consumption. CONCLUSIONS: Acetaminophen use during pregnancy was associated with a modest increased risk for offspring asthma, which was not modified by coffee consumption.


Assuntos
Acetaminofen/efeitos adversos , Asma/induzido quimicamente , Asma/epidemiologia , Café , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adulto , Asma/prevenção & controle , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Seguimentos , Humanos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Fatores de Risco , Adulto Jovem
10.
Reprod Toxicol ; 58: 234-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26536653

RESUMO

Hypericum perforatum (HP; also known as St. John's Wort) is one of the most commonly used herbal therapies in the management of depressive illness. The aim of this study was to evaluate the potential side effects of HP during pregnancy on pregnancy outcome. Using data from the Danish National Birth Cohort (DNBC), we investigated outcomes among 38 HP exposed pregnancies compared to a group of 90,128 women. Associations between HP use and gestational age, preterm birth, birth weight, malformations and Apgar scores were investigated. Preterm birth did not differ across the groups. While the prevalence of malformations in the HP exposed group was slightly higher (8.1%) than observed in the control groups (3.3%; p=0.13), this was based on only three cases and was not of any specific pattern.


Assuntos
Antidepressivos/efeitos adversos , Hypericum/efeitos adversos , Extratos Vegetais/efeitos adversos , Complicações na Gravidez/induzido quimicamente , Anormalidades Induzidas por Medicamentos/epidemiologia , Anormalidades Induzidas por Medicamentos/etiologia , Adulto , Antidepressivos/isolamento & purificação , Bases de Dados Factuais , Dinamarca/epidemiologia , Feminino , Humanos , Hypericum/química , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Nascimento Prematuro/induzido quimicamente , Nascimento Prematuro/epidemiologia , Prevalência , Medição de Risco , Fatores de Risco , Inquéritos e Questionários
11.
PLoS One ; 9(1): e87450, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24498107

RESUMO

BACKGROUND: Manganese superoxide dismutase (MnSOD) inhibits oxidative damage and cancer therapy effectiveness. A polymorphism in its encoding gene (SOD2: Val16Ala rs4880) may confer poorer breast cancer survival, but data are inconsistent. We examined the association of SOD2 genotype and breast cancer recurrence (BCR) among patients treated with cyclophosphamide-based chemotherapy (Cyclo). We compared our findings with published studies using meta-analyses. METHODS: We conducted a population-based case-control study of BCR among women in Jutland, Denmark. Subjects were diagnosed with non-metastatic breast cancer from 1990-2001, received adjuvant Cyclo, and were registered in the Danish Breast Cancer Cooperative Group. We identified 118 patients with BCR and 213 matched breast cancer controls. We genotyped SOD2 and used conditional logistic regression to compute the odds ratio (OR) and associated 95% confidence intervals (95% CI) of BCR. We used random-effects meta-analytic models to evaluate the association of SOD2 polymorphisms and BCR. RESULTS: The frequency of the SOD2-Ala allele was 70% in cases versus 71% in controls; 40% versus 44% were heterozygotes, and 30% versus 25% were homozygotes, respectively. Heterozygote and homozygote carriers of the Ala allele had no increased rate of BCR (OR = 1.1, 95%CI = 0.65, 2.0, and OR = 0.87, 95%CI = 0.47, 1.6, respectively). Five studies informed the meta-analytic models; summary estimates associating BCR for homozygote, or any inheritance of the variant Ala allele were 1.18 (95%CI = 0.74, 1.88), and 1.18, (95%CI = 0.91, 1.54), respectively. CONCLUSION: Our findings do not suggest that MnSOD enzymatic activity, as measured by SOD2 genotype, affects rates of BCR among patients treated with Cyclo.


Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Neoplasias da Mama , Ciclofosfamida/administração & dosagem , Mutação de Sentido Incorreto , Recidiva Local de Neoplasia , Sistema de Registros , Superóxido Dismutase , Alelos , Substituição de Aminoácidos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Dinamarca , Feminino , Heterozigoto , Homozigoto , Humanos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/enzimologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
12.
Environ Health Perspect ; 121(4): 433-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23552522

RESUMO

BACKGROUND: Diarylheptanoid (D3) isolated from the medicinal plant, Curcuma comosa, has estrogenic activity. OBJECTIVE: We aimed to elucidate the mechanism(s) of D3 action and compare it with that of 17ß-estradiol (E2) using both in vitro and in vivo uterine models. METHODS: We used human uterine (Ishikawa) cells to determine the estrogenic action of D3 on the activation and nuclear translocation of estrogen receptor α (ERα). In addition, we further characterized the uterine response to D3 treatment in vivo. RESULTS: D3 activated an estrogen responsive element (ERE) luciferase reporter through ERα, and molecular modeling suggested that D3 could be accommodated in the ERα binding pocket. Using modified ERα to assay ligand-dependent nuclear translocation, we observed D3-dependent ERα interaction and translocation. In mouse uteri, early- and late-phase estrogen-regulated gene responses were increased in D3-treated ovariectomized wild-type animals, in a manner similar to that of E2; no response was seen in ERα knockout animals. We observed a divergence in estrogen responses after D3 treatment: D3 induced robust DNA synthesis in uterine epithelial cells, linked to an increase in cell-cycle-related genes; however, no increase in uterine weight was observed 24 hr after treatment. D3 also affected uterine progesterone receptor expression patterns similar to E2. When D3 and E2 were administered together, we observed no additive or antagonistic effects of D3 on E2. Our findings suggest that D3 is a weak estrogenic agonist compound. CONCLUSION: D3 is a weakly acting phytoestrogen that mimics the mitogenic responses produced by E2 in an ERα-dependent manner, but it is unable to increase uterine weight or enhance or antagonize the effects of estrogen.


Assuntos
Curcuma/química , Diarileptanoides/metabolismo , Exposição Ambiental , Fitoestrógenos/metabolismo , Útero/efeitos dos fármacos , Animais , Linhagem Celular , Estradiol/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Camundongos , Microscopia Confocal , Ovariectomia , Extratos Vegetais/metabolismo , Reação em Cadeia da Polimerase , Receptores de Progesterona/metabolismo , Rizoma/química
13.
PLoS One ; 7(12): e51248, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23284672

RESUMO

BACKGROUND: Glucose-6-phosphate is imported into the amyloplast of potato tubers and thought to constitute the precursor for starch synthesis in potato tubers. However, recently it was shown that glucose-1-phosphate can also be imported into the amyloplast and incorporated into starch via an ATP independent mechanism under special conditions. Nonetheless, glucose-6-phosphate is believed to be the quantitatively important precursor for starch synthesis in potato. PRINCIPAL FINDING: Potato tubers of the high yielding cv Kuras had low gene expression of plastidial phophoglucomutase (PGM) and normal levels of transcripts for other enzymes involved in starch metabolism in comparison with medium and low yielding cultivars as determined by DeepSAGE transcriptome profiling. The decrease in PGM activity in Kuras was confirmed by measuring the enzyme activity from potato tuber extracts. Contrary to expectations, this combination lead to a higher level of intracellular glucose-1-phosphate (G1P) in Kuras suggesting that G1P is directly imported into plastids and can be quantitatively important for starch synthesis under normal conditions in high yielding cultivars. SIGNIFICANCE: This could open entirely new possibilities for metabolic engineering of the starch metabolism in potato via the so far uncharacterized G1P transporter. The perspectives are to increase yield and space efficiency of this important crop. In the light of the increasing demands imposed on agriculture to support a growing global population this presents an exciting new possibility.


Assuntos
Perfilação da Expressão Gênica , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Amido/biossíntese , Citosol/enzimologia , Citosol/metabolismo , Glucose-6-Fosfato/metabolismo , Glucofosfatos/metabolismo , Hexoses/química , Hexoses/metabolismo , Hidroliases/metabolismo , Espaço Intracelular/metabolismo , Plastídeos/enzimologia , Plastídeos/metabolismo , Solanum tuberosum/citologia , Solanum tuberosum/crescimento & desenvolvimento , Sacarose/química , Sacarose/metabolismo
14.
Phys Sportsmed ; 39(3): 163-71, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22030952

RESUMO

Elite athletes have a high prevalence of asthma and exercise-induced bronchoconstriction. Although respiratory symptoms can be suggestive of asthma, the diagnosis of asthma in elite athletes cannot be based solely on the presence or absence of symptoms; diagnosis should be based on objective measurements, such as the eucapnic voluntary hyperpnea test or exercise test. When considering that not all respiratory symptoms are due to asthma, other diagnoses should be considered. Certain regulations apply to elite athletes who require asthma medication for asthma. Knowledge of these regulations is essential when treating elite athletes. This article is aimed at physicians who diagnose and treat athletes with respiratory symptoms. It focuses on the pathogenesis of asthma and exercise-induced bronchoconstriction in elite athletes and how the diagnosis can be made. Furthermore, treatment of elite athletes with asthma, anti-doping regulations, and differential diagnoses such as exercise-induced laryngomalacia are discussed.


Assuntos
Asma Induzida por Exercício/diagnóstico , Asma Induzida por Exercício/terapia , Atletas , Antiasmáticos/uso terapêutico , Testes de Provocação Brônquica , Broncoconstrição , Diagnóstico Diferencial , Dopagem Esportivo , Teste de Esforço , Humanos , Apoio Nutricional , Pólen/efeitos adversos , Dispositivos de Proteção Respiratória
15.
Mol Cell ; 30(3): 315-24, 2008 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-18471977

RESUMO

We report the crystallographic structures of DNA polymerase beta with dG-dAMPCPP and dC-dAMPCPP mismatches in the active site. These premutagenic structures were obtained with a nonhydrolyzable incoming nucleotide analog, dAMPCPP, and Mn(2+). Substituting Mn(2+) for Mg(2+) significantly decreases the fidelity of DNA synthesis. The structures reveal that the enzyme is in a closed conformation like that observed with a matched Watson-Crick base pair. The incorrect dAMPCPP binds in a conformation identical to that observed with the correct nucleotide. To accommodate the incorrect nucleotide and closed protein conformation, the template strand in the vicinity of the active site has shifted upstream over 3 A, removing the coding base from the active site and generating an abasic templating pocket. The primer terminus rotates as its complementary template base is repositioned. This rotation moves O3' of the primer terminus away from the alpha-phosphate of the incoming nucleotide, thereby deterring misincorporation.


Assuntos
Pareamento Incorreto de Bases , DNA Polimerase beta/química , Conformação de Ácido Nucleico , Conformação Proteica , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Sítios de Ligação , Cristalografia por Raios X , DNA/biossíntese , DNA/química , DNA Polimerase beta/genética , DNA Polimerase beta/metabolismo , Humanos , Manganês/química , Manganês/metabolismo , Modelos Moleculares , Dados de Sequência Molecular
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