Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
1.
Nicotine Tob Res ; 24(12): 1959-1967, 2022 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-35704338

RESUMO

INTRODUCTION: Regulators are considering reducing the nicotine content in cigarettes to a minimally addictive level. This could particularly benefit smokers from populations vulnerable to heavy smoking and difficulties quitting. We assessed predictors of adherence among adults from vulnerable populations assigned to use very low nicotine content cigarettes (VLNCs) in randomized clinical trials, to identify characteristics of those who require additional assistance if a nicotine reduction policy were implemented. AIMS AND METHODS: Data came from three populations of vulnerable adult smokers assigned to use VLNC cigarettes (0.4 mg/g nicotine) during 12-week randomized controlled trials (n = 286): Socioeconomically disadvantaged women of reproductive age, opioid-maintained adults, and adults with affective disorders. Logistic and linear regressions modeled predictors of adherence based on changes in cotinine at week-6 and week-12 assessments relative to baseline, and as a 90% reduction in cotinine relative to baseline (full adherence: yes/no). Predictors included satisfaction with study cigarettes, craving, nicotine dependence severity, withdrawal, population membership, baseline affective-disorder symptoms, and sociodemographic characteristics. RESULTS: Dependence severity was negatively associated with both adherence measures at week 6 (p < .01), whereas increased satisfaction with study cigarettes and age were positively associated with both measures at weeks 6 and 12 (p < .01). Opioid-maintained adults exhibited reduced adherence and were less likely to reach full adherence at week 12 compared to disadvantaged women (p = .02). CONCLUSIONS: Factors associated with VLNC adherence in vulnerable populations are similar to those in the general population of smokers. Furthermore, studies are indicated investigating nicotine supplements (e.g., e-cigarettes, NRT) to support highly dependent adults faced with using VLNCs. IMPLICATIONS: This study identified factors predicting difficulty maintaining adherence to a regimen of very low nicotine content cigarettes (VLNC) among adults from vulnerable populations. Findings suggested that factors predicting difficulty maintaining adherence (greater nicotine dependence and low satisfaction with study-provided VLNC) were common across vulnerable smokers and the general population of adults who smoke. Furthermore, research should investigate alternatives to support highly dependent adults, such as pairing VLNC with supplemental, noncombusted nicotine. Some vulnerable populations (e.g., opioid-maintained adults) may be especially in need of supplemental, noncombusted nicotine.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Abandono do Hábito de Fumar , Produtos do Tabaco , Tabagismo , Adulto , Humanos , Feminino , Nicotina , Cotinina , Abandono do Hábito de Fumar/psicologia , Populações Vulneráveis , Analgésicos Opioides , Fumar
2.
BMC Cancer ; 20(1): 940, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32998716

RESUMO

BACKGROUND: After High-Dose Methotrexate (HD-MTX), folinic acid rescue therapy (Leucovorin) is administered to reduce side effects in pediatric acute lymphoblastic leukemia (ALL) patients. Leucovorin and MTX are structural analogues, possibly competing for cellular transport and intracellular metabolism. We hypothesize that Leucovorin accumulates during consecutive courses, which might result in a lower MTX uptake. METHODS: We prospectively measured red blood cell (RBC) folate and MTX levels during four HD-MTX and Leucovorin courses in 43 patients treated according the DCOG ALL-11 protocol with 2-weekly HD-MTX (5 g/m2/dose) and Leucovorin (15 mg/m2/dose) using LC-MS/MS. We estimated a linear mixed model to assess the relationship between these variables over time. RESULTS: Both RBC MTX-PG and folate levels increased significantly during protocol M. MTX-PG2-5 levels increased most substantially after the first two HD-MTX courses (until median 113.0 nmol/L, IQR 76.8-165.2) after which levels plateaued during the 3d and 4th course (until median 141.3 nmol/L, IQR 100.2-190.2). In parallel, folate levels increased most substantially after the first two HD-MTX courses (until median 401.6 nmol/L, IQR 163.3-594.2) after which levels plateaued during the 3d and 4th course (until median 411.5 nmol/L, IQR 240.3-665.6). The ratio folate/MTX-PG decreased significantly over time, which was mostly due to the relatively higher increase (delta) of MTX-PG. CONCLUSION: These results suggest that the increase in RBC folate levels does not seem to have a large effect on RBC MTX levels. Future studies, assessing competition of Leucovorin and MTX on other cellular mechanisms which might negatively affect treatment efficacy, are necessary.


Assuntos
Ácido Fólico/sangue , Metotrexato/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/sangue , Criança , Pré-Escolar , Cromatografia Líquida , Eritrócitos/efeitos dos fármacos , Feminino , Humanos , Lactente , Leucovorina/administração & dosagem , Leucovorina/sangue , Masculino , Metotrexato/administração & dosagem , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Espectrometria de Massas em Tandem , Resultado do Tratamento
4.
PLoS One ; 15(5): e0231588, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32421698

RESUMO

We have recently established a protocol to grow wildtype human oral mucosa organoids. These three-dimensional structures can be maintained in culture long-term, do not require immortalization, and recapitulate the multilayered composition of the epithelial lining of the oral mucosa. Here, we validate the use of this model to study the effect of Leucovorin (LV) on Methotrexate (MTX)-induced toxicity. MTX is a chemotherapeutic agent used in the treatment of pediatric acute lymphoblastic leukemia. Although effective, the use of MTX often results in severe side-effects, including oral mucositis, which is characterized by epithelial cell death. Here, we show that organoids are sensitive to MTX, and that the addition of LV reduces MTX toxicity, in both a concentration- and timing-dependent manner. Additionally, we show that a 24 hour 'pretreatment' with LV reduces MTX-induced cell death, suggesting that such a pretreatment could decrease mucositis in patients. Taken together, we provide the first in vitro model to study the effect of MTX on wildtype oral mucosa cells. Our findings underscore the relevance of the clinically applied LV regimen and highlight the potential of this model to further optimize modifications in dosing and timing of Leucovorin on oral mucosa cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Apoptose/efeitos dos fármacos , Mucosa Bucal/efeitos dos fármacos , Organoides/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Estomatite/patologia , Adolescente , Criança , Humanos , Técnicas In Vitro , Leucovorina/administração & dosagem , Metotrexato/administração & dosagem , Mucosa Bucal/patologia , Técnicas de Cultura de Órgãos , Organoides/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Estomatite/induzido quimicamente
5.
Crit Rev Oncol Hematol ; 142: 1-8, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31323533

RESUMO

INTRODUCTION: This study aimed to determine the efficacy of different Leucovorin regimens to reduce oral mucositis in children with acute lymphoblastic leukemia after high-dose Methotrexate (HD-MTX). METHODS: Twelve articles were included in a systematic literature review. Articles were categorized into low/medium/high risk of bias. RESULTS: As no randomized controlled trial assessing the effect of Leucovorin has been performed, the efficacy of Leucovorin to reduce oral mucositis remains unknown. Leucovorin was initiated at 24, 36 or 42 h after HD-MTX at a dose of 15 or 30 mg/m2. No meta-analysis could be performed as treatment regimens differed. When comparing studies with similar HD-MTX doses, we observed lower oral mucositis rates in regimens with higher cumulative doses of Leucovorin and early initiation of Leucovorin after MTX. CONCLUSION: Even though future studies are necessary, higher cumulative Leucovorin doses and early initiation of Leucovorin after start of MTX seem to reduce oral mucositis.


Assuntos
Leucovorina/uso terapêutico , Metotrexato/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Estomatite/tratamento farmacológico , Adolescente , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Criança , Pré-Escolar , Humanos , Lactente , Leucovorina/administração & dosagem , Metotrexato/uso terapêutico , Estomatite/induzido quimicamente , Estomatite/prevenção & controle , Resultado do Tratamento , Adulto Jovem
6.
Support Care Cancer ; 27(1): 183-190, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29922939

RESUMO

PURPOSE: Children with acute lymphoblastic leukemia (ALL) are at increased risk of vitamin D deficiency, which might make them more susceptible to developing adverse events. Previous studies showed that low vitamin D levels were associated with an increased inflammatory mucosal state and impaired mucosal tissue barriers. We examined the prevalence of vitamin D deficiency and studied the association between vitamin D levels and methotrexate (MTX)-induced oral mucositis in pediatric ALL. METHODS: We assessed 25-hydroxyvitamin D (25(OH)D3) and 24,25-dihydroxyvitamin D (24,25(OH)2D3) levels in 99 children with ALL before the start of 4 × 5 g/m2 high-dose methotrexate (HD-MTX) (T0) and in 81/99 children after discontinuation of HD-MTX (T1). Two cutoff values for vitamin D deficiency exist: 25(OH)D3 levels < 30 and < 50 nmol/L. Oral mucositis was defined as grade ≥ 3 according to the National Cancer Institute Criteria. RESULTS: Vitamin D deficiency occurred in respectively 8% (< 30 nmol/L) and 33% (< 50 nmol/L) of the patients at T0, and more frequently in children > 4 years of age as compared to children between 1 and 4 years of age. A decrease in 25(OH)D3 levels during HD-MTX therapy was associated with developing severe oral mucositis (OR 1.6; 95% CI [1.1-2.4]). 25(OH)D3 and 24,25(OH)2D3 levels at T0 and the change in 24,25(OH)2D3 levels during therapy were not associated with the development of severe oral mucositis. CONCLUSIONS: This study showed that vitamin D deficiency occurs frequently in pediatric ALL patients above the age of 4 years. A decrease in 25(OH)D3 levels during MTX therapy was observed in children with ALL that developed severe oral mucositis.


Assuntos
Metotrexato/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Estomatite/induzido quimicamente , Estomatite/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitamina D/sangue , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Humanos , Lactente , Masculino , Metotrexato/administração & dosagem , Países Baixos/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Prevalência , Estomatite/sangue , Estomatite/complicações , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Suspensão de Tratamento , Adulto Jovem
7.
Phys Rev Lett ; 121(1): 012501, 2018 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-30028163

RESUMO

Lifetime measurements of excited states in the neutron-rich nucleus ^{43}S were performed by applying the recoil-distance method on fast rare-isotope beams in conjunction with the Gamma-Ray Energy Tracking In-beam Nuclear Array. The new data based on γγ coincidences and lifetime measurements resolve a doublet of (3/2^{-}) and (5/2^{-}) states at low excitation energies. Results were compared to the π(sd)-ν(pf) shell model and antisymmetrized molecular dynamics calculations. The consistency with the theoretical calculations identifies a possible appearance of three coexisting bands near the ground state of ^{43}S: the K^{π}=1/2^{-} band built on a prolate-deformed ground state, a band built on an isomer with a 1f_{7/2}^{-1} character, and a suggested excited band built on a newly discovered doublet state. The latter further confirms the collapse of the N=28 shell closure in the neutron-rich region.

8.
Phys Rev Lett ; 121(26): 262501, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30636164

RESUMO

An enhanced low-energy electric dipole (E1) strength is identified for the weakly bound excited states of the neutron-rich isotope ^{27}Ne. The Doppler-shift lifetime measurements employing a combination of the γ-ray tracking array GRETINA, the plunger device, and the S800 spectrograph determine the lower limit of 0.030 e^{2} fm^{2} or 0.052 W.u. for the 1/2^{+}→3/2^{-} E1 transition in ^{27}Ne, representing one of the strongest E1 strengths observed among the bound discrete states in this mass region. This value is at least 30 times larger than that measured for the 3/2^{-} decay to the 3/2_{gs}^{+} ground state. A comparison of the present results to large-scale shell-model calculations points to an important role of core excitations and deformation in the observed E1 enhancement, suggesting a novel example of the electric dipole modes manifested in weakly bound deformed systems.

9.
Eur J Radiol ; 85(12): 2275-2280, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27842677

RESUMO

BACKGROUND AND PURPOSE: Primary MRI diagnosis of spinal intramedullary tumor-suspected lesions can be challenging and often requires spinal biopsy or resection with a substantial risk of neurological deficits. We evaluated whether Diffusion Tensor Imaging (DTI) tractography can facilitate the differential diagnosis. MATERIALS AND METHODS: Twenty-five consecutive patients with an intramedullary tumor-suspected lesion considered for spinal surgery were studied with a Diffusion-weighted multi-shot read out segmented EPI sequence (RESOLVE). White matter tracts ("streamlines") were calculated using the FACT algorithm and visually co-registered to a T2-weighted 3D sequence. The fused images were assessed concerning spinal streamline appearance as normal, displaced or terminated. Definite diagnosis was verified by histological analysis or further clinical work-up. RESULTS: All patients with normal appearing streamlines (n=6) showed an acute inflammatory demyelinating pathology in the further clinical work-up. In 10 patients streamline displacing lesions were found from which 5 patients underwent a surgical treatment with histologically confirmed low-grade tumors like ependymomas and pilocytic astrocytomas. In nine patients streamlines were terminated, from which 6 patients received a histology proven diagnoses with a more heterogenous spectrum (3 cases of high grade tumor, 1 case of low grade tumor with intralesional hemorrhage and 2 cases with gliosis but no tumor cells). CONCLUSION: Using multi-shot DTI spinal tractography acute inflammatory lesions can be differentiated from other tumorous intramedullary lesions. The entity diagnosis of spinal tumors seems to be more challenging, primarily due to the variety of factors like invasivity, expansion or intralesional hemorrhage.


Assuntos
Imagem de Tensor de Difusão/métodos , Neoplasias da Medula Espinal/diagnóstico por imagem , Adolescente , Adulto , Idoso , Algoritmos , Astrocitoma/diagnóstico por imagem , Astrocitoma/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Ependimoma/diagnóstico por imagem , Ependimoma/patologia , Feminino , Gliose/diagnóstico por imagem , Gliose/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Mielite/diagnóstico por imagem , Mielite/patologia , Procedimentos Neurocirúrgicos , Estudos Prospectivos , Razão Sinal-Ruído , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Neoplasias da Medula Espinal/patologia , Adulto Jovem
10.
Anal Bioanal Chem ; 405(5): 1673-81, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23239179

RESUMO

The folate antagonist methotrexate (MTX) is the anchor drug in the treatment of rheumatoid arthritis. The therapeutic effects of MTX are attributed to the intracellular levels of MTX, present in the cell as polyglutamates (MTXPGn). We developed a new liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS)-based assay to separately quantitate MTXPGn in red blood cells using stable-isotope-labelled internal standards. Samples were analyzed by LC-ESI-MS/MS using a Waters Acquity UPLC BEH C18 column with a 5-100% organic gradient of 10 mM ammonium bicarbonate (pH 10) and methanol. The analysis consisted of simple sample preparation and a 6-min run time. Detection was done using a Waters Acquity UPLC coupled to a Waters Quattro Premier XE with electrospray ionization operating in the positive ionization mode. Assay validation was performed following recent Food and Drug Administration guidelines. The method was linear from 1-1,000 nM for all MTXPGn (R(2) > 0.99). The coefficient of variation ranged from 1-4% for intraday precision and 6-15% for interday precision. Samples were stable for at least 1 month at -80 °C. Recovery ranged from 98-100%, and the relative matrix-effect varied from 95-99%. The lower limit of quantitation was 1 nM for each MTXPGn. Fifty patient samples from the tREACH study were analyzed. The MTXPGn concentration and distribution of these samples were comparable with values reported in literature. The developed LC-ESI-MS/MS method for the quantitative measurement of MTXPGn in red blood cells is both sensitive and precise within the clinically relevant range. The method can be easily applied in clinical laboratories due to the combination of simple pre-treatment with robust LC-ESI-MS/MS.


Assuntos
Antirreumáticos/sangue , Artrite Reumatoide/tratamento farmacológico , Monitoramento de Medicamentos/métodos , Eritrócitos/química , Metotrexato/sangue , Ácido Poliglutâmico/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Antirreumáticos/análise , Artrite Reumatoide/sangue , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Limite de Detecção , Metotrexato/análise , Ácido Poliglutâmico/análise , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos
11.
Bone ; 50(6): 1401-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22465697

RESUMO

BACKGROUND: An elevated level of plasma homocysteine (Hcy) is a known risk factor for osteoporotic fractures. In addition, Hcy is related to DNA-methylation metabolism. To determine whether the association between Hcy and fractures is explained by an altered methylation capacity, we investigated the associations between levels of s-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) and fracture risk. METHODS: We studied 503 females aged 55 years and over from the Rotterdam Study (RS) in whom plasma Hcy, SAM and SAH levels were measured. Bone mineral density (BMD) at the hip was assessed using DXA. Incident fractures were recorded over a mean period of 7.0 years. Cox proportional hazards analysis and linear regression were used to assess relationships between plasma metabolite levels, incident osteoporotic fractures and BMD. RESULTS: Over a total of 3502 person-years of follow-up, 103 subjects sustained at least one osteoporotic fracture. Whereas incidence of osteoporotic fractures was associated with quartiles of Hcy (p=0.047), it was not associated with quartiles of SAM, SAH or SAM/SAH-ratio (all p for trend>0.6). Stepwise linear regression showed that SAM/SAH-ratio, but not Hcy, was independently associated with hip BMD (ß=0.073, p=0.025). CONCLUSION: Since SAM, SAH and SAM/SAH-ratio were not associated with osteoporotic fractures, alterations in methylation capacity most likely do not appear to be an important factor in the association between Hcy and fractures.


Assuntos
Homocisteína/sangue , Fraturas por Osteoporose/sangue , Fraturas por Osteoporose/etiologia , Idoso , Densidade Óssea , Feminino , Humanos , Incidência , Modelos Lineares , Metilação , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Fraturas por Osteoporose/epidemiologia , Modelos de Riscos Proporcionais , Fatores de Risco , S-Adenosil-Homocisteína/sangue , S-Adenosilmetionina/sangue
12.
Intensive Care Med ; 38(6): 984-90, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22446990

RESUMO

PURPOSE: Venous thromboembolism (VTE) is a common but often overlooked life-threatening complication of critical illness. The aim of this cross-sectional survey was to assess current practice of thromboprophylaxis as well as adherence to international guidelines. METHODS: After ethics committee approval, all intensive care units in Austrian hospitals treating adult patients were invited to participate in this web-based survey. Anonymized data on each patient treated at the participating intensive care units on Coagulation Day 2010 were collected using an electronic case report form. Risk assessment, choice and monitoring of anticoagulants, means of mechanical prophylaxis, and demographic data were recorded. RESULTS: Data from 325 critically ill patients were collected. Patients had a median of four risk factors for thrombosis and 6 % suffered from VTE. Of the 325 patients, 80 % received low molecular weight heparins subcutaneously, 10 % received unfractionated heparin intravenously, 1 % received alternative anticoagulants and 9 % received no pharmacological prophylaxis. Mechanical prophylaxis was used in 49 % with a predominant use of graduated compression stockings. In 39 % a combination of pharmacological and mechanical prophylaxis was applied and 5 % received no prophylaxis at all. Overall guideline adherence was 40 % on Coagulation Day 2010. CONCLUSION: Current practice of thromboprophylaxis is predominantly based on the administration of low molecular weight heparins prescribed at rather arbitrary doses without a discernible relationship to drug monitoring, thromboembolic risk factors, vasopressor use or fluid balance. The use of mechanical prophylaxis, evaluation of risk scores and overall guideline adherence must be further encouraged by education, training and communication.


Assuntos
Unidades de Terapia Intensiva , Tromboembolia/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Áustria , Feminino , Pesquisas sobre Atenção à Saúde , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica/estatística & dados numéricos , Fatores de Risco , Meias de Compressão , Inquéritos e Questionários , Tromboembolia/etiologia
13.
Eur Addict Res ; 16(2): 99-107, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20160444

RESUMO

BACKGROUND: Little comparable information is available regarding clinical characteristics of opioid-dependent women from different countries. In the present study, women from the USA, Canada and a Central European country, Austria, screened for participation in the Maternal Opioid Treatment Human Experimental Research study, were compared with respect to their demographic and addiction histories. METHODS: Pregnant women (n = 1,074) were screened for study participation using uniformed clinical criteria and instruments. The screening results were compared with regard to exclusion, demographics, drug use, and psychosocial and treatment histories. RESULTS: Compared to the screened US and Canadian women, Austrian women were more likely to be younger (p < 0.001), white (p < 0.001), had significantly lower levels of educational attainment (p < 0.001), were less likely to use opioids daily (p < 0.001) and more likely to have been prescribed buprenorphine (p < 0.001). Compared to both rural and urban US groups, the Austrian group was less likely to have legal issues (p < 0.001) and was younger when first prescribed agonist medication (p < 0.001). CONCLUSION: The differences between North American and European groups may offer unique insights concerning treatment and pregnancy outcomes for opioid-dependent pregnant women.


Assuntos
Usuários de Drogas/estatística & dados numéricos , Programas de Rastreamento/métodos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Seleção de Pacientes , Complicações na Gravidez/tratamento farmacológico , Adolescente , Adulto , Distribuição por Idade , Áustria , Canadá , Usuários de Drogas/psicologia , Escolaridade , Definição da Elegibilidade , Feminino , Humanos , Antagonistas de Entorpecentes/uso terapêutico , Transtornos Relacionados ao Uso de Opioides/psicologia , Gravidez , Complicações na Gravidez/psicologia , População Rural , Fatores Socioeconômicos , Estados Unidos , População Urbana , Adulto Jovem
14.
Anaesthesist ; 58(11): 1119-22, 2009 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-19795099

RESUMO

Heparin-induced thrombocytopenia (HIT) type II is a life-threatening complication of heparin therapy. The present case report describes the therapeutic management of HIT type II with thrombosis using the direct thrombin inhibitor argatroban in an intensive care patient after successful surgery of a ruptured infrarenal abdominal aortic aneurysm. Despite high dosing and long-term application of argatroban, anticoagulation remained uncritical and was well controllable by monitoring the activated partial thromboplastin time. In consideration of the pharmacological characteristics, therapy suspension due to invasive interventions and switching to an oral vitamin K antagonist by defined algorithm resulted in an effective management.


Assuntos
Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Heparina/efeitos adversos , Ácidos Pipecólicos/uso terapêutico , Trombina/antagonistas & inibidores , Trombocitopenia/induzido quimicamente , Trombocitopenia/tratamento farmacológico , Trombose/complicações , Idoso , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Arginina/análogos & derivados , Exantema/complicações , Exantema/tratamento farmacológico , Humanos , Masculino , Tempo de Tromboplastina Parcial , Contagem de Plaquetas , Sulfonamidas , Trombocitopenia/complicações , Trombose/sangue
15.
Am J Drug Alcohol Abuse ; 35(5): 375-80, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20180667

RESUMO

BACKGROUND: Little is known about the prevalence and severity of smoking in pregnant opioid dependent patients. OBJECTIVES: To first characterize the prevalence and severity of smoking in pregnant patients screened for a randomized controlled trial, Maternal Opioid Treatment: Human Experimental Research (MOTHER), comparing two agonist medications; and second, to compare the MOTHER screening sample to published samples of other pregnant and/or patients with substances use disorders. METHODS: Pregnant women (N = 108) screened for entry into an agonist medication comparison study were retrospectively compared on smoking variables to samples of pregnant methadone-maintained patients (N = 50), pregnant opioid or cocaine dependent patients (N = 240), non-pregnant methadone-maintained women (N = 75), and pregnant non-drug-addicted patients (N = 1,516). RESULTS: Of screened patients, 88% (n = 95) smoked for a mean of 140 months (SD = 79.0) starting at a mean age of 14 (SD = 3.5). This rate was similar to substance use disordered patients and significantly higher compared to general pregnant patients (88% vs. 22%, p < .001). CONCLUSION AND SCIENTIFIC SIGNIFICANCE: Aggressive efforts are needed to reduce/eliminate smoking in substance-abusing pregnant women.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Metadona/uso terapêutico , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Fumar/epidemiologia , Adulto , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Entorpecentes/uso terapêutico , Gravidez , Prevalência , Índice de Gravidade de Doença , Inquéritos e Questionários
17.
J Thromb Haemost ; 2(5): 750-3, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15099281

RESUMO

BACKGROUND: Venous thrombosis is a multicausal disease involving both genetic as well as acquired risk factors. Hyperhomocysteinemia is associated with a 2-fold increased risk of recurrent venous thrombosis (RVT). Recently, the 894 G > T variant of endothelial nitric oxide synthase (eNOS) was postulated to be associated with hyperhomocysteinemia. OBJECTIVES: We hypothesized an interrelation of hyperhomocysteinemia, the eNOS 894 G > T variant and RVT risk. METHODS: The eNOS 894 G > T variant was studied in 170 cases with a history of RVT and 433 controls from the general population. RESULTS: The eNOS 894 TT genotype may increase RVT risk [odds ratio (OR) 1.3 (0.7-2.6)], but no association of the eNOS 894 G > T variant with elevated homocysteine was found in controls. Interestingly, in RVT cases the coexistence of both the 894 TT genotype and elevated tHcy levels (> 90th percentile) was more frequently present than in controls, which led to a substantially increased risk of recurrent venous thrombosis [fasting tHcy OR 5.3 (1.1-24.1), postload tHcy OR 6.5 (1.6-29.5)]. CONCLUSION: The results of the present study demonstrate that the eNOS 894 G > T variation interacts with elevated tHcy levels, leading to an increased risk of recurrent thrombotic events. This interaction points in the direction of S-nitrosation as a mechanism by which homocysteine exerts its detrimental effects on the hemostatic system.


Assuntos
Hiper-Homocisteinemia/complicações , Óxido Nítrico Sintase/genética , Polimorfismo de Nucleotídeo Único , Trombose Venosa/genética , Estudos de Casos e Controles , Genótipo , Homocisteína/metabolismo , Humanos , Hiper-Homocisteinemia/epidemiologia , Epidemiologia Molecular , Óxido Nítrico Sintase Tipo III , Nitrosação , Razão de Chances , Recidiva , Risco , Trombose Venosa/epidemiologia , Trombose Venosa/etiologia
18.
Cell Mol Biol (Noisy-le-grand) ; 50(8): 911-6, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15704255

RESUMO

Hyperhomocysteinemia (HHcy) is associated with impaired endothelial-dependent vasodilatation and increased risk of atherosclerosis and thrombosis. Here, we summarize some of our previous work on the effect of HHcy on pathways involved in endothelium-dependent vasodilatation, and present new data concerning the endothelium-derived hyperpolarizing factor (EDHF)-mediated vasodilatation. We showed that the 894 G>T single-nucleotide polymorphism in the human endothelial nitric oxide synthase gene (eNOS) increased the risk of recurrent venous thrombosis in individuals with elevated homocysteine levels, indicating that the pathophysiological mechanism in HHcy involves impaired NO-mediated vasodilatation. In addition, the EDHF-mediated vasodilatation of the renal artery was disturbed in diet-induced hyperhomocysteinemic rats. Interestingly, we demonstrated that pretreatment of rats with periodate-oxidized adenosine (Adox), which is an inhibitor of S-adenosylhomocysteine hydrolase, prevented the methionine-induced rise in plasma total Hcy (tHcy) levels but not the inhibition of the EDHF pathway. Furthermore, we demonstrated that S-adenosylhomocysteine (AdoHcy) and S-adenosylmethionine (AdoMet) levels were increased in the kidneys of diet-induced HHcy rats, resulting in a decreased AdoMet:AdoHcy ratio. In addition, we demonstrated that mRNA expression of Connexin 40, which is one of the structural subunits of gap-junctions, was down-regulated in endothelial cells of HHcy rats, and correlated with elevated AdoHcy levels in kidney of these rats. These finding suggest a key role for AdoHcy in relation to decreased Cx40 mRNA expression and impaired EDHF-mediated vasodilatation of HHcy rats.


Assuntos
Fatores Biológicos/metabolismo , Hiper-Homocisteinemia/metabolismo , Óxido Nítrico/metabolismo , Animais , Conexinas/metabolismo , Endotélio Vascular/metabolismo , Junções Comunicantes , Humanos , Rim/metabolismo , Modelos Biológicos , Razão de Chances , Estresse Oxidativo , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , S-Adenosil-Homocisteína/metabolismo , Fatores de Tempo , Vasodilatação , Trombose Venosa/metabolismo , Proteína alfa-5 de Junções Comunicantes
19.
Amino Acids ; 23(1-3): 331-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12373555

RESUMO

UNLABELLED: Oxidative damage to DNA has been well documented in cardiac cells isolated from diabetic patients and rats with streptozotocin-induced diabetes mellitus (DM). This study evaluates possible molecular mechanisms for early events in the development of DM-induced cardiomyopathy. METHODS: To analyze the mechanism of overexpression of p21(WAF1/CIP1) and inhibition of cyclin D(1) expression in cardiomyocytes of diabetic rats we examined the methylation status of these genes by MS-PCR and assessed the possibility of epigenetic control of their expression. RESULTS: We found that the steady-state expression of both genes is influenced by their methylation status, as an epigenetic event, of their 5'-flanking regions upon development of diabetes. CONCLUSIONS: Oxidative damage contributes to the development of cardiomyopathy via p53-dependent activation of cardiac cell death. This pathway includes de novomethylation of the P53-inducible p21(WAF1/CIP1)-gene encoding a protein which binds to and inhibits a broad range of cyclin-cyclin-dependent kinase complexes.


Assuntos
Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Ciclina D1/genética , Ciclinas/genética , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Animais , Ilhas de CpG , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/metabolismo , Dano ao DNA , Metilação de DNA , Feminino , Miócitos Cardíacos/fisiologia , Regiões Promotoras Genéticas , Ratos , Ratos Wistar
20.
Drug Alcohol Depend ; 67(2): 149-56, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12095664

RESUMO

This study compared the subjective, physiological, and psychomotor effects of atomoxetine and methylphenidate with placebo in healthy volunteers. Sixteen non-dependent light drug users participated in six experimental sessions, receiving placebo, atomoxetine (20, 45 and 90 mg) and methylphenidate (20 and 40 mg) using a double-blind, Latin square design. Subjective drug effects were assessed using Visual Analog Scales (VAS), the Addiction Research Center Inventory (ARCI) and Adjective Rating Scales (ARS). Psychomotor performance was evaluated using the Digit Symbol Substitution Test (DSST). Physiological measures were also collected throughout the sessions. Assessments were conducted before drug administration and 30, 60, 90, 120, 150, 180 and 240 min following dosing. Forty milligrams methylphenidate produced significant increases on the stimulant portions of the VAS and ARS and the benzedrine, amphetamine, morphine-benzedrine and lysergic acid diethylamine (LSD) subscales of the ARCI relative to placebo. Ninety mg atomoxetine was reported to be unpleasurable relative to placebo as indicated by significant increases on the 'bad' and 'sick' portions of the VAS, and on the LSD subscale of the ARCI. Compared with placebo, both methylphenidate doses significantly increased systolic blood pressure (BP) and heart rate (HR). For atomoxetine, 90 mg increased diastolic BP, 45 and 90 mg increased systolic BP, and all three doses increased HR relative to placebo. Neither compound produced significant differences from placebo on DSST performance. These results suggest that atomoxetine does not induce subjective effects similar to methylphenidate and suggest that it is unlikely that atomoxetine will have abuse liability.


Assuntos
Metilfenidato/farmacologia , Propilaminas/farmacologia , Desempenho Psicomotor/efeitos dos fármacos , Desempenho Psicomotor/fisiologia , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Adulto , Análise de Variância , Cloridrato de Atomoxetina , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Método Duplo-Cego , Feminino , Humanos , Análise dos Mínimos Quadrados , Masculino , Avaliação de Resultados em Cuidados de Saúde , Transtornos Relacionados ao Uso de Substâncias/psicologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...