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1.
Chem Res Toxicol ; 37(2): 220-226, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38235526

RESUMO

We measured levels of nitrosonornicotine (NNN) and 4-[methyl(nitroso)amino]-1-(3-pyridinyl)-1-butanone (NNK), the two most carcinogenic tobacco-specific nitrosamines, in the filler, binder, and wrapper of 50 cigars: 19 large cigars, 23 cigarillos, and 8 little cigars. The average NNN and NNK levels were 10.6 and 3.70 µg/g, respectively. These levels are 5- and 7-fold higher, respectively, than those of commercial cigarettes. The differences in NNN and NNK levels between cigars and cigarettes reflect differences in tobacco blends and tobacco treatments, such as fermentation. The average tobacco NNN and NNK levels of large cigars were 3- and 5-fold higher than those of cigarillos and little cigars, respectively. Large cigars also exhibited a significantly broader range of NNN and NNK than cigarillos and little cigars. The NNN and NNK levels in cigarillos are comparable to those of little cigars. These results are consistent with earlier studies finding that cigarillos and little cigars have similar tobacco blends with lower NNN and NNK content than large cigar tobacco blends.


Assuntos
Nitrosaminas , Produtos do Tabaco , Carcinógenos/análise
2.
Chem Res Toxicol ; 36(2): 202-212, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36638203

RESUMO

This study examined the variation of benzo[a]pyrene (B[a]P), N'-nitrosonornicotine (NNN), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) levels in 16 smokeless tobacco products from several different product subcategories obtained at two different locations and at two different procurement times. B[a]P quantities range from 0.6 to 160 ng/g on a wet-weight basis, whereas NNN and NNK quantities range from 276 to 10473 ng/g and 79 to 28882 ng/g, respectively. The B[a]P, NNN, and NNK quantities vary widely among various smokeless tobacco product categories and among various brands within each product subcategory. Dry snuff products contain the highest B[a]P, NNN, and NNK quantities, whereas loose and portioned snus products contain the lowest B[a]P, NNN, and NNK levels. In general, variation of B[a]P, NNN, and NNK levels across four sets of each product brand purchased six months apart and at two different locations show statistically significant differences (p < 0.05), although with a much narrower product set-to-set variability.


Assuntos
Nitrosaminas , Produtos do Tabaco , Tabaco sem Fumaça , Benzo(a)pireno , Nicotiana , Carcinógenos/análise
3.
Nicotine Tob Res ; 25(6): 1202-1206, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-36702747

RESUMO

INTRODUCTION: Studies have evaluated the role of menthol cigarettes on various addiction-related outcomes; however, the effect of varying menthol content on these outcomes has not been evaluated. We developed a method to amend non-menthol SPECTRUM Research Cigarettes to contain menthol at four different levels. AIMS AND METHODS: SPECTRUM Research Cigarettes, NRC 600 (0.8 mg nicotine; 10 mg tar), were modified to contain target menthol amounts at 3, 6, and 12 mg/cigarette by injecting 25 µL ethanol/triacetin/menthol solutions of varying concentrations (120 mg menthol/mL, 240 mg/mL, and 480 mg/mL) into four distinct locations in the filter and tobacco rod. Menthol content was tested in triplicate in the whole cigarette and in the tobacco rod and filter at 1, 24, 48, and 72 hours for each target menthol level using an extraction solution of quinoline in methyl-tert-butyl ether and measured using gas chromatography with flame ionization detection. RESULTS: Injections into the filter and tobacco rod (12.5 µL each) yielded equal menthol distribution up to 72 hours. However, total menthol content decreased from an average of 90.3% of the target menthol concentration at 1 hour to 80.7% at 72 hours in cigarettes stored individually in glass tubes at room temperature. Analysis of urinary menthol glucuronide confirmed that amended cigarettes used within 24 hours of injection delivered dose-related menthol levels to participants in a clinical laboratory setting. CONCLUSION: This method can be used to modify cigarettes with a range of reliable menthol levels in both filter and tobacco rod for use in laboratory and clinical research. IMPLICATIONS: This study presents a technique for modifying cigarettes with different levels of menthol that can reliably deliver dose-related menthol levels to participants when smoked in a clinical study. The technique can be used to quickly amend cigarettes to examine the independent effects of varying flavor and additive levels on smoking behavior, nicotine pharmacokinetics, mainstream smoke emissions, and other laboratory or clinical research outcomes.


Assuntos
Nicotina , Produtos do Tabaco , Humanos , Nicotina/análise , Produtos do Tabaco/análise , Fumar , Nicotiana , Fumaça/análise
4.
Regul Toxicol Pharmacol ; 133: 105199, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35662636

RESUMO

Smokeless tobacco products expose adult and youth tobacco users to various addictive and carcinogenic constituents that can cause long-term nicotine dependence and oral cancers. In this study, nicotine, benzo[a]pyrene (B[a]P), N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), acetaldehyde, crotonaldehyde, formaldehyde, moisture, and pH levels in 16 smokeless tobacco products were measured on a wet-weight basis (wwb). In addition, change in analytical variability with increasing replicate measurements was assessed. Total nicotine in the products varied from 6.2 to 35.5 mg/g. The percentage of total nicotine in the unprotonated form ranged from 0.1 to 62%; whereas, product moisture varied from 7.4 to 57%. The quantities of harmful and potentially harmful constituents (HPHCs) range from 0.46 to 179.9 ng/g for B [a]P, 270-12206 and 81-20716 ng/g for NNN and NNK, respectively, and 0.33-6.85 and 0.13-5.67 µg/g for acetaldehyde and formaldehyde, respectively. This study shows wide variation in smokeless tobacco product HPHC quantities. The results also show that analytical variability stabilizes after seven replicate measurements.


Assuntos
Nitrosaminas , Produtos do Tabaco , Tabaco sem Fumaça , Acetaldeído , Adolescente , Adulto , Carcinógenos/análise , Formaldeído , Humanos , Concentração de Íons de Hidrogênio , Nicotina , Nicotiana/química , Produtos do Tabaco/efeitos adversos , Tabaco sem Fumaça/efeitos adversos
6.
Chem Res Toxicol ; 35(6): 940-953, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35612471

RESUMO

Mainstream smoke yields of hydrogen cyanide (HCN) and three aromatic amines, 1-aminonaphthalene, 2-aminonaphthalene, and 4-aminobiphenyl, from 60 little cigar brands currently on the US market were measured for both International Organization for Standardization (ISO) and Canadian Intense (CI) smoking regimens. The smoke yields are compared with those from 50 cigarette products measured by Counts et al. of Philip Morris USA (PMUSA) in 2005 [Counts et al. Regul. Toxicol. Pharmacol. 2005 41, 185-227] and 50 cigarette products measured by the Centers for Disease Control and Prevention (CDC) in cooperation with the Food and Drug Administration (FDA) in 2012 [Tynan et al. Consumption of Cigarettes and Combustible Tobacco: United States, 2000-2011. In Morbidity and Mortality Weekly Report; Centers for Disease Control and Prevention, 2012; 565-580]. For the little cigars, the average HCN yield with the ISO smoking regimen is 335 µg/cigar (range: 77-809 µg/cigar), which is 332% higher than the average of 50 PMUSA 2005 cigarettes and 243% higher than the average of 50 CDC/FDA 2012 cigarettes. For the CI smoking regimen, the average HCN yield is 619 µg/cigar (range: 464-1045 µg/cigar), which is 70.5% higher than the average of 50 PMUSA 2005 cigarettes and 69% higher than the average of the 50 CDC/FDA 2012 cigarettes. For aromatic amines, the average ISO smoking regimen smoke yields are 36.6 ng/cigar (range: 15.9-70.6 ng/cigar) for 1-aminonaphthalene, 24.6 ng/cigar (range: 12.3-36.7 ng/cigar) for 2-aminonaphthalene, and 5.6 ng/cigar (range: 2.3-17.2 ng/cigar) for 4-aminobiphenyl. The average ISO yields of aromatic amines from little cigars are 141% to 210% higher compared to the average yields of 50 PMUSA cigarettes. The average CI smoke regimen yields are 73.0 ng/cigar (range: 32.1-112.2 ng/cigar) for 1-aminonaphthalene, 45.2 ng/cigar (range: 24.6-74.8 ng/cigar) for 2-aminonaphthalene, and 12.7 ng/cigar (range: 5.5-37.5 ng/cigar) for 4-aminobiphenyl. The average CI aromatic amine yields are 143% to 220% higher compared to the average yields of 50 PMUSA cigarettes, almost identical to the relative yields under the ISO smoking regimen. Both HCN and aromatic amine yields are 1.5× to 3× higher for the tested little cigars than for the conventional cigarettes; however, there are notable differences in the relationships of these yields to certain product characteristics, such as weight, ventilation, and tobacco type. The higher smoke yields of these compounds from little cigars indicates that cigar smokers may be at risk of a higher exposure to HCN and aromatic amines on a per stick basis and thus increased health concerns.


Assuntos
Fumaça , Produtos do Tabaco , 1-Naftilamina , 2-Naftilamina , Aminas , Canadá , Cianeto de Hidrogênio , Fumaça/análise , Nicotiana , Estados Unidos
7.
Chem Res Toxicol ; 34(7): 1713-1717, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34228438

RESUMO

Two-tail t test statistical analyses of International Organization for Standardization nonintense and Canadian Intense mainstream smoke yields of total particulate matter, tar, nicotine, and carbon monoxide from cigarettes show that mean quantities are generally higher for a linear smoking machine at a 95% confidence level but a rotary smoking machine has better precision. A novel "super pad" analysis concept combines four smaller filter pads from a linear smoking machine, resulting in increased mean constituent yields and reduced variability. Although measurement variability is still greater than that of rotary machines, super padding may be useful to reduce the variance caused by linear smoking machines.


Assuntos
Fumaça/análise , Canadá , Monóxido de Carbono/análise , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Humanos , Nicotina/análise , Material Particulado/análise , Fumar , Alcatrões/análise
8.
Chem Res Toxicol ; 34(4): 1034-1045, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33667338

RESUMO

Cigars are among the broad variety of tobacco products that have not been as extensively studied and characterized as cigarettes. Small cigars wrapped in a tobacco-containing sheet, commonly referred to as little cigars, are a subcategory that are similar to conventional cigarettes with respect to dimensions, filters, and overall appearance. Tobacco-specific nitrosamines (TSNAs) are carcinogens in the tobacco used in both little cigars and cigarettes. This study uses a validated high-performance liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) method to measure the TSNAs 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN) in the tobacco filler and the nonintense International Organization for Standardization smoking regimen, ISO 3308, and the newer ISO 20778 Cigarette Intensive (CI) smoking regimen mainstream smoke of 60 commercial little cigars. Tobacco filler NNK and NNN quantities ranged from 26 to 2950 and 1440 to 12 100 ng/g tobacco, respectively. NNK and NNN by the ISO nonintense smoking regimen ranged from 89 to 879 and 200 to 1540 ng/cigar, respectively; by the CI regimen, NNK and NNN ranged from 138 to 1570 and 445 to 2780 ng/cigar, respectively. The average transfer (%) for NNK and NNN from tobacco filler to mainstream smoke was 24% and 36% by the ISO nonintense and CI smoking regimens, respectively. By the ISO nonintense and CI smoking regimens, mainstream smoke NNK and NNN yields showed a moderate to strong correlation (ISO nonintense, R2 = 0.60-0.68, p < 0.0001; CI, R2 = 0.78-0.81, p < 0.0001) with tobacco filler NNK and NNN quantities. In addition, the mainstream smoke NNK and NNN yields of little cigars were determined to be 3- to 5-fold higher compared to previously tested commercial cigarettes. The mainstream smoke NNK and NNN yields have wide variation among commercial little cigars and suggest that, despite design similarities to cigarettes, machine-smoke yields of carcinogenic TSNAs are higher in little cigars.


Assuntos
Nicotiana/química , Nitrosaminas/análise , Fumaça/análise , Produtos do Tabaco/análise
9.
Chem Res Toxicol ; 34(3): 704-712, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33512154

RESUMO

The mainstream smoke yields of five volatile organic compounds (VOCs) were determined from 60 commercial U.S. little cigar products under ISO 3308 and Canadian Intense (CI) smoking regimens on linear smoking machines using a gas sampling bag collection. The five VOCs, 1,3-butadiene, acrylonitrile, benzene, isoprene, and toluene were analyzed using an automated GC/MS analytical method validated for measuring various VOCs in mainstream smoke. The VOCs range in amounts from micrograms to milligrams per little cigar. VOC deliveries vary considerably among the little cigar products under the ISO smoking regimen primarily due to varying filter ventilation. Under the CI smoking regimen where filter ventilation is blocked, the delivery range narrows, although individual and total VOC yields are approximately 2 fold higher than those under the ISO smoking regimen. Correlation analysis reveals strong associations between acrylonitrile and 1,3-butadiene or toluene under the ISO smoking regimen. Compared to cigarettes, little cigars delivered substantially higher VOC mainstream smoke yields under both ISO and CI smoking regimens. Moreover, little cigar smoke also contains higher VOCs than cigarette smoke when adjusted for mass of tobacco.


Assuntos
Fumaça/análise , Produtos do Tabaco/análise , Compostos Orgânicos Voláteis/análise
10.
Parkinsonism Relat Disord ; 82: 128-132, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33321452

RESUMO

INTRODUCTION: In 2019, we published the results of a Phase IIb randomized controlled trial of putaminal encapsulated porcine choroid plexus cell (termed NTCELL®) administration in patients with Parkinson's disease. This study failed to meet its primary efficacy end-point of a change in UPDRS part III score in the 'off' state at 26-weeks post-implant. However, a number of secondary end-points reached statistical significance. We questioned whether with longer follow-up, clinically significant improvements would be observed. For this reason, we decided to follow-up all patients periodically to week 104. Herein, we report the results of this long-term follow-up. METHODS: All 18 patients included in the original study were periodically re-assessed at weeks 52, 78 and 104 post-implant. At each time-point, motor and non-motor function, quality of life and levodopa equivalent daily dose was assessed using a standardized testing battery. RESULTS: At week 104, no significant differences in UPDRS part III scores in the 'off' state were observed in any of the treatment groups compared to baseline. Only a single serious adverse event - hospitalisation due to Parkinson's disease rigidity not responding to changes in medications - was considered potentially related to the implant procedure. There was no evidence of xenogeneic viral transmission. CONCLUSION: Un-blinded, long-duration follow-up to week 104 post-implantation showed no evidence that putaminal NTCELL® administration produces significant clinical benefit in patients with moderately advanced Parkinson's disease.


Assuntos
Alginatos , Plexo Corióideo/citologia , Avaliação de Resultados em Cuidados de Saúde , Doença de Parkinson/terapia , Putamen , Transplante Heterólogo/efeitos adversos , Idoso , Animais , Cápsulas/uso terapêutico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/cirurgia , Putamen/cirurgia , Suínos
11.
Nicotine Tob Res ; 20(3): 393-398, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28340022

RESUMO

Introduction: Cigars are combusted tobacco products consisting of filler, binder, and wrapper, which are derived from tobacco. Despite the abundance of literature on the composition of traditional combusted cigarettes, research is limited on the physical and chemical properties of cigars. Therefore, research on cigar properties may be useful to better understand their health impact. Methods: In this study, twenty large cigar and cigarillo products were characterized for physical properties (ie, weight, length, and diameter), filler nicotine content, and tobacco pH. Tobacco pH was used to calculate free nicotine content, free nicotine concentration, and percent free nicotine for all cigars using the Henderson-Hasselbach equation. An additional analysis was performed on a second batch of two large cigar and two cigarillo brands to determine within-brand consistency. All analyses were performed in triplicate. Results: The initial analysis of the twenty cigars showed that cigars exhibited wide variation in product size and nicotine content, although tobacco pH was similar across cigars. Furthermore, in the two large cigar and cigarillo brands analyzed a second time, there was considerable within-brand variance in nicotine content and concentration between the first and second analyses. Conclusions: While only a small sample of commercially-available cigars was analyzed, our data suggest there is wide variability in nicotine content and some physical properties in the domestic cigar market. The data may help to inform potential future regulatory decisions related to these products. Implications: This study reveals some of the challenges to experimental cigar research and illustrates the need to characterize cigar products (eg, nicotine and tobacco content) before use in clinical studies. Additional studies and characterization of the physical and chemical properties of cigars may be useful to further understand these products' toxicity, abuse potential, and public health impact.


Assuntos
Nicotina/análise , Controle de Qualidade , Produtos do Tabaco/análise , Humanos , Saúde Pública/tendências , Fumar/epidemiologia , Fumar/tendências , Nicotiana/química , Estados Unidos/epidemiologia
13.
Chem Res Toxicol ; 30(2): 540-551, 2017 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-28001416

RESUMO

Tobacco-specific nitrosamines (TSNAs) are N-nitroso-derivatives of pyridine-alkaloids (e.g., nicotine) present in tobacco and cigarette smoke. Two TSNAs, N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), are included on the Food and Drug Administration's list of harmful and potentially harmful constituents (HPHCs) in tobacco products and tobacco. The amounts of four TSNAs (NNK, NNN, N-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT)) in the tobacco and mainstream smoke from 50 U.S. commercial cigarette brands were measured from November 15, 2011 to January 4, 2012 using a validated HPLC/MS/MS method. Smoke samples were generated using the International Organization of Standardization (ISO) and Canadian Intense (CI) machine-smoking regimens. NNN and NAT were the most abundant TSNAs in tobacco filler and smoke across all cigarette brands, whereas NNK and NAB were present in lesser amounts. The average ratios for each TSNA in mainstream smoke to filler content is 29% by the CI smoking regimen and 13% for the ISO machine-smoking regimen. The reliability of individual TSNAs to predict total TSNA amounts in the filler and smoke was examined. NNN, NAT, and NAB have a moderate to high correlation (R2 = 0.61-0.98, p < 0.0001), and all three TSNAs individually predict total TSNAs with minimal difference between measured and predicted total TSNA amounts (error < 7.4%). NNK has weaker correlation (R2 = 0.56-0.82; p < 0.0001) and is a less reliable predictor of total TSNA quantities. Tobacco weight and levels of TSNAs in filler influence TSNA levels in smoke from the CI machine-smoking regimen. In contrast, filter ventilation is a major determinant of levels of TSNAs in smoke by the ISO machine-smoking regimen. Comparative analysis demonstrates substantial variability in TSNA amounts in tobacco filler and mainstream smoke yields under ISO and CI machine-smoking regimens among U.S. commercial cigarette brands.


Assuntos
Nicotiana/química , Nitrosaminas/análise , Fumaça/análise , Carcinógenos/análise , Cromatografia Líquida , Espectrometria de Massas em Tandem , Estados Unidos
14.
Nicotine Tob Res ; 18(7): 1575-80, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26259988

RESUMO

INTRODUCTION: In 2011 menthol cigarettes accounted for 32 percent of the market in the United States, but there are few literature reports that provide measured menthol data for commercial cigarettes. To assess current menthol application levels in the US cigarette market, menthol levels in cigarettes labeled or not labeled to contain menthol was determined for a variety of contemporary domestic cigarette products. METHOD: We measured the menthol content of 45 whole cigarettes using a validated gas chromatography/mass spectrometry method. RESULTS: In 23 cigarette brands labeled as menthol products, the menthol levels of the whole cigarette ranged from 2.9 to 19.6mg/cigarette, with three products having higher levels of menthol relative to the other menthol products. The menthol levels for 22 cigarette products not labeled to contain menthol ranged from 0.002 to 0.07mg/cigarette. The type of packaging (soft vs. hard pack) for a given cigarette product does not appear to affect menthol levels based on the current limited data. CONCLUSIONS: Menthol levels in cigarette products labeled as containing menthol are approximately 50- to 5000-fold higher than those in cigarette products not labeled as containing menthol. In general, menthol content appears to occur within discrete ranges for both mentholated and nonmentholated cigarettes. IMPLICATIONS: This study shows that menthol may be present in non-mentholated cigarettes and adds to the understanding of how menthol may be used in cigarette products. It is the first systematic study from the same laboratory which will readily enable comparison among menthol and non-menthol cigarettes.


Assuntos
Aromatizantes/análise , Marketing , Mentol/análise , Embalagem de Produtos , Produtos do Tabaco/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Indústria do Tabaco/normas , Estados Unidos
15.
Chem Res Toxicol ; 28(8): 1616-26, 2015 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-26158771

RESUMO

The mainstream smoke yields of 14 polycyclic aromatic hydrocarbons (PAHs) were determined for 50 commercial U.S. cigarettes using a validated GC/MS method with the International Organization of Standardization (ISO) and Canadian Intense (CI) smoking machine regimens. PAH mainstream smoke deliveries vary widely among the commercial cigarettes with the ISO smoking regimen primarily because of differing filter ventilation. The more abundant, lower molecular weight PAHs such as naphthalene, fluorene, and phenanthrene predominantly comprise the total PAH yields. In contrast, delivery yields of high molecular weight PAHs such as benzo[b]fluoranthene, benzo[e]pyrene, benzo[k]fluoranthene, and benzo[a]pyrene (BaP) are much lower. Comparative analysis of PAHs deliveries shows brand specific differences. Correlation analysis shows strong positive associations between BaP and most of the other PAHs as well as total PAHs. The results suggest that BaP may be a representative marker for other PAH constituents in cigarette smoke generated from similarly blended tobacco, particularly those PAHs with similar molecular weights and chemical structures.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Fumaça/análise , Fumar , Produtos do Tabaco/análise , Estrutura Molecular , Peso Molecular , Estados Unidos
16.
J Lipid Res ; 54(12): 3491-505, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24103848

RESUMO

The purpose of this study was to determine the core biological processes perturbed in the subcutaneous adipose tissue of familial combined hyperlipidemia (FCHL) patients. Annotation of FCHL and control microarray datasets revealed a distinctive FCHL transcriptome, characterized by gene expression changes regulating five overlapping systems: the cytoskeleton, cell adhesion and extracellular matrix; vesicular trafficking; lipid homeostasis; and cell cycle and apoptosis. Expression values for the cell-cycle inhibitor CDKN2B were increased, replicating data from an independent FCHL cohort. In 3T3-L1 cells, CDKN2B knockdown induced C/EBPα expression and lipid accumulation. The minor allele at SNP site rs1063192 (C) was predicted to create a perfect seed for the human miRNA-323b-5p. A miR-323b-5p mimic significantly reduced endogenous CDKN2B protein levels and the activity of a CDKN2B 3'UTR luciferase reporter carrying the rs1063192 C allele. Although the allele displayed suggestive evidence of association with reduced CDKN2B mRNA in the MuTHER adipose tissue dataset, family studies suggest the association between increased CDKN2B expression and FCHL-lipid abnormalities is driven by factors external to this gene locus. In conclusion, from a comparative annotation analysis of two separate FCHL adipose tissue transcriptomes and a subsequent focus on CDKN2B, we propose that dysfunctional adipogenesis forms an integral part of FCHL pathogenesis.


Assuntos
Tecido Adiposo/metabolismo , Inibidor de Quinase Dependente de Ciclina p15/genética , Regulação da Expressão Gênica , Hiperlipidemia Familiar Combinada/genética , Células 3T3-L1 , Adipogenia/genética , Tecido Adiposo/patologia , Animais , Ciclo Celular/genética , Células HEK293 , Haplótipos , Humanos , Hiperlipidemia Familiar Combinada/patologia , Masculino , Camundongos , Pessoa de Meia-Idade
17.
Mov Disord ; 25(11): 1670-4, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20568096

RESUMO

Multiple lines of evidence point to mitochondrial oxidative stress as a potential pathogenic cause for Parkinson's disease (PD). MitoQ is a powerful mitochondrial antioxidant. It is absorbed orally and concentrates within mitochondria where it has been shown to protect against oxidative damage. We enrolled 128 newly diagnosed untreated patients with PD in a double-blind study of two doses of MitoQ compared with placebo to explore the hypothesis that, over 12 months, MitoQ would slow the progression of PD as measured by clinical scores, particularly the Unified Parkinson Disease Rating Scale. We showed no difference between MitoQ and placebo on any measure of PD progression. MitoQ does not slow the progression of PD, and this finding should be taken into account when considering the oxidative stress hypothesis for the pathogenesis of PD.


Assuntos
Antioxidantes/uso terapêutico , Compostos Organofosforados/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Ubiquinona/análogos & derivados , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Ubiquinona/uso terapêutico
18.
Liver Int ; 30(7): 1019-26, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20492507

RESUMO

BACKGROUND: Increased oxidative stress and subsequent mitochondrial damage are important pathways for liver damage in chronic hepatitis C virus (HCV) infection; consequently, therapies that decrease mitochondrial oxidative damage may improve outcome. The mitochondria-targeted anti-oxidant mitoquinone combines a potent anti-oxidant with a lipophilic cation that causes it to accumulate several-hundred fold within mitochondria in vivo. AIMS: In this phase II study, we investigated the effect of oral mitoquinone on serum aminotransferases and HCV RNA levels in HCV-infected patients. METHODS: Thirty HCV patients who were either non-responders or unsuitable candidates for standard-of-care (pegylated interferon plus ribavirin) were randomized to receive mitoquinone (40 or 80 mg) or placebo once daily for 28 days, and serum aminotransferases and HCV RNA levels were measured. RESULTS: Both treatment groups showed significant decreases in absolute and percentage changes in serum alanine transaminase (ALT) from baseline to treatment day 28 (P<0.05). There was also a significant difference between incremental area under the curve for ALT between baseline and day 28 for the 40 mg treatment group against placebo (P<0.05). The differences in plasma ALT activity from baseline to day 28 in both mitoquinone groups compared with placebo did not reach significance (P>0.05). There was no change in HCV load on mitoquinone treatment. CONCLUSIONS: Administration of the mitochondria-targeted anti-oxidant mitoquinone significantly decreased plasma ALT and aspartate aminotransferase in patients with chronic HCV infection, and this suggests that mitoquinone may decrease necroinflammation in the liver in these patients. As mitochondrial oxidative damage contributes to many other chronic liver diseases, such as steatohepatitis, further studies using mitochondria-targeted anti-oxidants in HCV and other liver diseases are warranted.


Assuntos
Antioxidantes/uso terapêutico , Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Fígado/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Compostos Organofosforados/uso terapêutico , Ubiquinona/uso terapêutico , Administração Oral , Adulto , Alanina Transaminase/sangue , Antioxidantes/administração & dosagem , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Método Duplo-Cego , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/metabolismo , Hepatite C Crônica/patologia , Humanos , Interferons/uso terapêutico , Fígado/metabolismo , Fígado/patologia , Fígado/virologia , Masculino , Pessoa de Meia-Idade , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Mitocôndrias Hepáticas/virologia , Compostos Organofosforados/administração & dosagem , RNA Viral/sangue , Ribavirina/uso terapêutico , Fatores de Tempo , Resultado do Tratamento , Ubiquinona/administração & dosagem , Carga Viral
19.
Eur J Cardiothorac Surg ; 37(6): 1360-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20153663

RESUMO

OBJECTIVE: Circulating monocytes may counter systemic pro-inflammatory and haemolytic insults through the expression and shedding of the haemoglobin scavenger receptor (CD163). This prospective study aims to assess the effects of coronary artery bypass grafting with and without cardiopulmonary bypass (CPB) on haemoglobin scavenging and anti-inflammatory monocyte behaviour. METHODS: Forty consecutive patients underwent coronary surgery using CPB (n=20) and off-pump (n=20) techniques. Peri-operative blood samples were taken until the fifth day following surgery and statistical comparison performed to baseline using group- and subject-based analysis. Monocyte receptor expression and plasma concentrations of anti-inflammatory molecules were measured by flow cytometry and enzyme-linked immunosorbent assay, respectively. RESULTS: Monocyte CD163 expression was significantly elevated post-operatively in both surgical groups with (p=0.001) and without CPB (p=0.000) at 24-48h. By contrast, shed CD163 (p=0.02) and haemoglobin-haptoglobin complexes (p=0.000) in plasma were only significantly elevated in the on-pump group at 2-4h. Subject-based analysis demonstrated that CPB is an independent predictor of monocyte CD163 (p=0.002) and plasma sCD163 (p=0.01) concentration adjusting for the measurement timing. Significant downregulation of the monocyte major histocompatibility complex II receptor was observed in both surgical groups, whereas lipopolysaccharide receptor (CD14) expression only declined following on-pump surgery. The anti-inflammatory cytokine interleukin (IL)-10 was elevated post-operatively in both surgical groups peaking earlier in the on-pump group (2h) versus off-pump group (4h). The immunoregulatory IL-6 cytokine was significantly upregulated at 4h in both groups. CONCLUSION: Coronary artery bypass surgery induces monocyte-associated anti-inflammatory and immunoregulatory responses. There was no significant difference in haemolysis although the effect on monocyte CD163 and plasma sCD163 concentration was significantly different between the two groups. Compensation for varying pro-inflammatory and haemolytic insults may explain the differences observed. Therapeutic strategies for inducing such desirable circulating monocytes may potentially improve surgical outcome and patient recovery.


Assuntos
Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Ponte de Artéria Coronária/métodos , Hemoglobinas/metabolismo , Monócitos/metabolismo , Receptores de Superfície Celular/sangue , Receptores Depuradores/sangue , Idoso , Ponte Cardiopulmonar , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Ponte de Artéria Coronária sem Circulação Extracorpórea/métodos , Feminino , Antígenos de Histocompatibilidade Classe II/sangue , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , Receptores de Lipopolissacarídeos/sangue , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos
20.
J Heart Valve Dis ; 17(5): 526-32, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18980086

RESUMO

BACKGROUND AND AIM OF THE STUDY: Patients with mechanical heart valves require anticoagulation which is associated with significant maternal mortality (1-4%) and fetal complications (31%) in pregnancy. The study aim was to identify anticoagulant protocols and outcomes for pregnant women undergoing heart valve replacement (HVR) in the United Kingdom. METHODS: Women aged between 18 and 45 years and registered with the United Kingdom Heart Valve Registry (UKHVR) each completed a questionnaire, and their obstetric notes were reviewed. The data analyzed included valve type (mechanical, bioprosthetic, homograft), valve site (mitral, aortic, tricuspid, pulmonary), anticoagulation at confirmation of pregnancy, between 6-12 weeks and from 12 weeks to term, delivery, maternal and fetal outcomes, and cause of death. The summary statistics and a descriptive review of the findings are reported. RESULTS: Of 2,532 women eligible for the study, 922 responded. Among these women, 72 became pregnant, with 60 pregnancies in the mechanical valve (MV) group and 45 in the tissue valve (TV) group. Three anticoagulation regimes were used during early pregnancy: unfractionated heparin (UFH), low-molecular-weight heparin (LMWH) or warfarin. All women received warfarin in the second trimester and heparin for delivery. Live births were recorded in 30% of MV pregnancies and in 60% of TV pregnancies. Miscarriage rates differed markedly (37% MV versus 2% TV). Fetal outcome was poorest in the warfarin-only group, with embryopathy occurring at a dose level of 6 mg. The maternal outcomes did not differ significantly among groups. High-dose heparin during the first trimester and for delivery was effective for the majority of mechanical valves. CONCLUSION: The study results illustrate the diverse and uncertain manner in which UKHVR patients are managed during pregnancy. A national notification system would record much-needed prospective information on anticoagulation and pregnancy outcomes, thus aiding evidence-based management.


Assuntos
Anticoagulantes/uso terapêutico , Bioprótese , Implante de Prótese de Valva Cardíaca , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Aborto Espontâneo/mortalidade , Adolescente , Adulto , Anticoagulantes/efeitos adversos , Causas de Morte , Relação Dose-Resposta a Droga , Feminino , Doenças Fetais/induzido quimicamente , Doenças Fetais/mortalidade , Insuficiência Cardíaca/mortalidade , Heparina/efeitos adversos , Heparina/uso terapêutico , Heparina de Baixo Peso Molecular/efeitos adversos , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Gravidez , Complicações Cardiovasculares na Gravidez/mortalidade , Resultado da Gravidez , Fatores de Risco , Reino Unido , Varfarina/efeitos adversos , Varfarina/uso terapêutico
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