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1.
ESMO Open ; 8(6): 102048, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37977000

RESUMO

BACKGROUND: Identification of factors associated with survival after ascites diagnosis in metastatic pancreatic cancer (mPC) patients may guide treatment decisions and help to maintain quality of life in this highly symptomatic patient collective. PATIENTS AND METHODS: All patients treated for mPC at the Medical University of Vienna between 2010 and 2019 developing ascites throughout their course of disease were identified by retrospective chart review. General risk factors, metastatic sites, systemic inflammation and liver function parameters, as well as type of treatment after ascites diagnosis were investigated for associations with survival. RESULTS: One hundred and seventeen mPC patients with ascites were included in this study. Median time from mPC to ascites diagnosis was 8.9 months (range 0-99 months) and median overall survival (OS) after ascites diagnosis was 27.4 days (range 21.3-42.6 days). Identified prognostic factors at ascites diagnosis independently associated with an impaired OS were presence of liver metastases [hazard ratio (HR): 2.07, 95% confidence interval (CI) 1.13-3.79, P = 0.018), peritoneal carcinomatosis (HR: 1.74, 95% CI 1.11-2.71, P = 0.015), and portal vein obstruction (HR: 2.52, 95% CI 1.29-4.90, P = 0.007). Compared with best supportive care, continuation of systemic therapy after ascites diagnosis was independently associated with survival (HR: 0.35, 95% CI 0.20-0.61, P < 0.001) with a median OS of 62 days (95% CI 51-129 days, P < 0.001) versus 16 days (95% CI 11-24 days), respectively. CONCLUSIONS: Liver and peritoneal metastases as well as portal vein obstruction were found to be prognostic factors after ascites diagnosis in mPC patients. Continuation of systemic therapy after ascites diagnosis was associated with a longer OS, which needs to be evaluated in larger clinical trials including quality-of-life assessment.


Assuntos
Neoplasias Hepáticas , Neoplasias Pancreáticas , Humanos , Estudos Retrospectivos , Ascite/etiologia , Ascite/patologia , Qualidade de Vida , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico
2.
ESMO Open ; 8(2): 101200, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36989885

RESUMO

BACKGROUND: Malignant ascites is common in metastatic pancreatic cancer (mPC) and its management still remains a clinical challenge. Early identification of patients at risk for ascites development may support and guide treatment decisions. MATERIALS AND METHODS: Data of patients treated for mPC at the Medical University of Vienna between 2010 and 2019 were collected by retrospective chart review. Ascites was defined as clinically relevant accumulation of intraperitoneal fluid diagnosed by ultrasound or computer tomography scan of the abdomen. We investigated the association between general risk factors, metastatic sites, liver function, systemic inflammation as well as portal vein obstruction (PVO) and ascites development. RESULTS: Among 581 patients with mPC included in this study, 122 (21.0%) developed ascites after a median of 8.7 months after diagnosis of metastatic disease. The occurrence of ascites led to an 8.9-fold increased risk of death [confidence interval (CI) 7.2-11, P < 0.001] with a median overall survival of 1 month thereafter. Clinical risk factors for ascites were male sex [hazard ratio (HR) 1.71, CI 1.00-2.90, P = 0.048], peritoneal carcinomatosis (HR 6.79, CI 4.09-11.3, P < 0.001), liver metastases (HR 2.16, CI 1.19-3.91, P = 0.011), an albumin-bilirubin (ALBI) score grade 3 (HR 6.79, CI 2.11-21.8, P = 0.001), PVO (HR 2.28, CI 1.15-4.52, P = 0.019), and an elevated C-reactive protein (CRP) (HR 4.19, CI 1.58-11.1, P = 0.004). CONCLUSIONS: Survival after diagnosis of ascites is very limited in mPC patients. Male sex, liver and peritoneal metastases, impaired liver function, PVO, as well as systemic inflammation were identified as independent risk factors for ascites development in this uniquely large real-life patient cohort.


Assuntos
Ascite , Neoplasias Pancreáticas , Humanos , Masculino , Feminino , Estudos Retrospectivos , Ascite/etiologia , Ascite/epidemiologia , Ascite/patologia , Fatores de Risco , Inflamação/complicações , Neoplasias Pancreáticas/tratamento farmacológico
3.
Blood Rev ; 56: 100987, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35779986

RESUMO

(Non-)selective non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used for musculoskeletal related pain. These cheap and easily accessible drugs may be of great value for hemophilia patients in developing countries and countries with a high rate of opioid poisoning, but also in developed countries due to potential joint protective effects. However, fear for adverse bleeding and cardiovascular events during the use of these drugs restrains prescription within this population. To give a complete overview of all publications reporting on safety, a systematic search till March 2021 was performed. All studies were reviewed and critically appraised and this resulted in 19 studies eligible for inclusion. Most studies with (non-)selective NSAIDs showed no evident risk for relevant adverse bleeding or cardiovascular events. However, some studies had a high risk of bias and studies reporting on cardiovascular events were limited. Future studies with longitudinal follow-up in well-defined large patient populations, including older patients, focusing on both adverse bleeding and cardiovascular events are required to confirm the alleged safe use.


Assuntos
Doenças Cardiovasculares , Hemofilia A , Humanos , Analgésicos Opioides , Hemofilia A/complicações , Hemofilia A/tratamento farmacológico , Anti-Inflamatórios não Esteroides/efeitos adversos , Medo , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia
4.
ESMO Open ; 6(3): 100168, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34098230

RESUMO

BACKGROUND: Brain metastases (BM) are a rare complication in colorectal cancer (CRC) patients and associated with an unfavorable survival prognosis. Primary tumor side (PTS) was shown to act as a prognostic and predictive biomarker in several trials including metastatic CRC (mCRC) patients. Here, we aim to investigate whether PTS is also associated with the outcome of CRC patients with BM. METHODS: Patients treated for CRC BM between 1988 and 2017 at an academic care center were included. Right-sided CRC was defined as located in the appendix, cecum and ascending colon and left-sided CRC was defined as located in the descending colon, sigma and rectum. RESULTS: Two hundred and eighty-one CRC BM patients were available for this analysis with 239/281 patients (85.1%) presenting with a left-sided and 42/281 patients (14.9%) with a right-sided primary CRC. BM-free survival (BMFS) was significantly longer in left-sided compared with right-sided CRC patients (33 versus 20 months, P = 0.009). Overall survival from CRC diagnosis as well as from diagnosis of BM was significantly longer in patients with a left-sided primary (42 versus 25 months, P = 0.002 and 5 versus 4 months, P = 0.005, respectively). In a multivariate analysis including graded prognostic assessment, PTS remained significantly associated with prognosis after BM (hazard ratio 0.65; 95% confidence interval: 0.46-0.92 months, P = 0.0016). CONCLUSIONS: PTS was associated with survival times after the rare event of BM development in CRC patients. Therefore, its prognostic value remains significant even thereafter.


Assuntos
Neoplasias Encefálicas , Neoplasias do Colo , Neoplasias Colorretais , Humanos , Prognóstico , Modelos de Riscos Proporcionais
5.
Blood Rev ; 47: 100781, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33277057

RESUMO

Hemophilic arthropathy (HA) causes major morbidity. Breakthrough therapies reduce the bleeding frequency tremendously, but well-defined joint outcome assessments with a focus on early changes and subclinical damage are lacking. Biomarkers reflecting joint tissue turnover/inflammation might be useful to predict invalidating arthropathy. This systematic review summarized and categorized publications on blood/urinary biomarkers in HA to provide leads for implementation. A PubMed/EMBASE search was performed on September 9, 2019. All publications were assessed and allocated to one or several BIPED-categories, based on the utility of biomarkers. Of the initial 1307 publications found, 27 were eligible for inclusion. The majority (81%, n = 32/42) was cross-sectional in design, including relatively small numbers of patients (median 44, interquartile range 35-78). Fourteen percent (n = 6/42) investigated dynamic changes around a bleeding or treatment. Only two studies investigated the prognostic value of biomarkers. Most promising biomarkers were serum Coll2-1, COL-18N, COMP, C1,2C, C2M, CS846, MIF, plasma sVCAM-1 and urinary CTX-II. Comparing performances and pooling data was not possible due to heterogeneity. Currently, biomarker research in HA is still in an explorative stage and not yet sufficient for translation into daily practice. Clearly, larger homogeneous longitudinal studies in well-defined populations should be performed for further development.


Assuntos
Proteínas Sanguíneas/metabolismo , Hemartrose/sangue , Biomarcadores/sangue , Hemartrose/diagnóstico , Humanos
6.
Neth J Med ; 77(10): 360-365, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31880268

RESUMO

BACKGROUND: Monitoring low-molecular-weight heparins is generally not required. However, guidelines advise to monitor anti-Xa levels in patients with renal insufficiency or a BMI above 50, and in pregnancy. Measuring anti-Xa levels is a complex challenge since sampling should be performed three to five hours after subcutaneous injection and after steady state concentrations have been reached. Strict compliance is pivotal for justified dose adjustments. OBJECTIVES: We questioned compliance to our protocol and performed this study to explore that. METHODS: This retrospective cohort study included patients ≥ 18 years receiving therapeutic dalteparin in a Dutch academic medical centre. Patients with a first anti-Xa level measured between February 23rd and December 30th, 2017 were selected. According to our local guideline, monitoring anti-Xa activity is indicated in patients on therapeutic doses of dalteparin who are pregnant, morbidly obese (BMI > 50), or have renal insufficiency (clearance < 60 ml/min). Accurate sampling was defined as measuring levels after at least three injections (after which a patient may reach steady state) and then four hours after the injection with dalteparin. The frequency of compliance to our protocol was assessed. RESULTS: We included 158 patients with 396 anti-Xa levels, of which 41% (65/158) of all first anti-Xa levels were drawn without appropriate indication. Almost half, 48% (211/396), were sampled incorrectly and 25% of these (53/211) were followed by a dose adjustment. In total, 74% (293/396) of the samples were not indicated or were taken at the wrong time. CONCLUSIONS: Monitoring anti-Xa levels is a complex clinical challenge. This study showed that non-compliance with recommendations for anti-Xa monitoring was high, often resulting in unjustified dose adjustments.


Assuntos
Anticoagulantes/uso terapêutico , Dalteparina/uso terapêutico , Inibidores do Fator Xa/sangue , Adesão à Medicação/estatística & dados numéricos , Tromboembolia Venosa/prevenção & controle , Tromboembolia Venosa/psicologia , Centros Médicos Acadêmicos , Adulto , Feminino , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Estudos Retrospectivos , Tromboembolia Venosa/tratamento farmacológico , Adulto Jovem
7.
Exp Gerontol ; 116: 14-19, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30562555

RESUMO

BACKGROUND: Age-related declines in function can limit older adults' independence with activities of daily living (ADLs). While task-specific training maybe a viable approach to improve function, limited clinical resources prevent extensive training on wide ranges of skills and contexts. Thus, training on one task for the benefit of another (i.e., transfer) is important in geriatric physical rehabilitation. The purpose of this study was to test whether motor transfer would occur between two functionally different upper extremity tasks that simulate ADLs in a sample of older adults following task-specific training. METHODS: Ninety community dwelling adults ages 43 to 94 years old performed two trials of a functional dexterity and functional reaching task at baseline, and were then assigned to one of two groups. The training group completed 3 days of task-specific training (150 trials) on the functional reaching task, whereas the no-training group received no training on either task. Both groups were re-tested on both tasks at the end of Day 3. RESULTS: No significant interactions were observed between group (training vs. no-training) and time (baseline vs. re-test) on the functional dexterity task (i.e. transfer task), indicating no difference in the average amount of change from baseline to re-test between the groups. However, post hoc bivariate linear regression revealed an effect of age on motor transfer within the training group. For those who trained on the functional reaching task, the amount of transfer to the dexterity task was inversely related to age. There was no significant relationship between age and motor transfer for the no-training group. DISCUSSION AND CONCLUSIONS: Results of our a priori group analysis suggest that functional reaching training did not, on average, transfer to the dexterity task. However, post hoc regression analysis showed that motor transfer was both experience- and age-dependent, such that motor transfer may decline with advanced age. Future research will consider how functional and cognitive aging influences transfer of motor skills across different activities of daily living.


Assuntos
Envelhecimento/psicologia , Destreza Motora , Transferência de Experiência , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Genes Brain Behav ; 15(6): 531-41, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27198479

RESUMO

Recent genome-wide association scans (GWAS) for reading and language abilities have pin-pointed promising new candidate loci. However, the potential contributions of these loci remain to be validated. In this study, we tested 17 of the most significantly associated single nucleotide polymorphisms (SNPs) from these GWAS studies (P < 10(-6) in the original studies) in a new independent population dataset from the Netherlands: known as Familial Influences on Literacy Abilities. This dataset comprised 483 children from 307 nuclear families and 505 adults (including parents of participating children), and provided adequate statistical power to detect the effects that were previously reported. The following measures of reading and language performance were collected: word reading fluency, nonword reading fluency, phonological awareness and rapid automatized naming. Two SNPs (rs12636438 and rs7187223) were associated with performance in multivariate and univariate testing, but these did not remain significant after correction for multiple testing. Another SNP (rs482700) was only nominally associated in the multivariate test. For the rest of the SNPs, we did not find supportive evidence of association. The findings may reflect differences between our study and the previous investigations with respect to the language of testing, the exact tests used and the recruitment criteria. Alternatively, most of the prior reported associations may have been false positives. A larger scale GWAS meta-analysis than those previously performed will likely be required to obtain robust insights into the genomic architecture underlying reading and language.


Assuntos
Estudo de Associação Genômica Ampla/normas , Desenvolvimento da Linguagem , Polimorfismo de Nucleotídeo Único , Leitura , Adolescente , Adulto , Idoso , Criança , Humanos , Alfabetização , Pessoa de Meia-Idade
9.
Breast Cancer Res Treat ; 157(1): 91-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27107570

RESUMO

We aimed to analyse the impact of breast cancer (BC) subtypes on the clinical course of disease with special emphasis on the occurrence of brain metastases (BM) and outcome in an elderly BC population. A total number of 706 patients ≥65 years receiving treatment for BC from 2007 to 2011 were identified from a BC database. 62 patients diagnosed with DCIS and 73 patients with incomplete datasets were excluded, leaving 571 patients for this analysis. Patient characteristics, biological tumour subtypes, and clinical outcome including overall survival (OS) were obtained by retrospective chart review. 380/571 (66, 5 %) patients aged 65-74 years were grouped among the young-old, 182/571 (31.9 %) patients aged 75-84 years among the old-old, and 29/571 (5.1 %) patients aged ≥85 years among the oldest-old. 392/571 (68.8 %) patients presented with luminal BC, 119/571 (20.8 %) with HER2-positive, and 59/571 (10.3 %) with triple-negative BC (TNBC). At 38 months median follow-up, 115/571 (20.1 %) patients presented with distant recurrence. A higher recurrence rate was observed in the HER2-positive subtype (43/119 (36.1 %)), as compared to TNBC (15/59 (25.4 %)) and luminal BC (57/392 (14.5 %); p < 0.001). BM were detected at a significantly higher rate in HER2-positive BC patients (9/119 (7.6 %)), as compared to TNBC (2/59 (3.4 %)) and luminal BC patients (6/392 (1.5 %); p = 0.003). Diagnosis of metastatic disease (HR 7.7; 95 % CI 5.2-11.4; p < 0.001) as well as development of BM (HR 3.5; 95 % CI 1.9-6.4; p < 0.001) had a significantly negative impact on OS in a time-dependent covariate cox regression model. In contrast to younger BC patients, outcome in this large cohort of elderly patients suggests that HER2-positive disease-not TNBC-featured the most aggressive clinical course with the highest rates of metastatic spread and BM. In-depth analysis regarding a potentially distinct biology of TNBC in elderly is therefore warranted.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias da Mama/classificação , Receptor ErbB-2/metabolismo , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Prognóstico , Estudos Retrospectivos
10.
Dermatology ; 198(3): 298-300, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10393458

RESUMO

Porocarcinoma is a very rare malignant tumor arising from the duct of eccrine sweat glands. Its prognosis is variable. We report on a patient who developed lymph node and multiple distant metastases, and who died of this malignancy only 6 months after the initial diagnosis.


Assuntos
Acrospiroma/patologia , Metástase Linfática , Couro Cabeludo , Neoplasias das Glândulas Sudoríparas/patologia , Neoplasias Abdominais/secundário , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/secundário
11.
Ter Arkh ; 70(12): 31-5, 1998.
Artigo em Russo | MEDLINE | ID: mdl-10067247

RESUMO

AIM: To assess preoperative stress in patients with ischemic heart disease (IHD) and its influence on the course of early intraoperative period. MATERIALS AND METHODS: 79 patients scheduled for aortocoronary bypass operation were studied to assess the phenomenon of preoperative psychoemotional stress (clinical characteristics, personal anxiety, humoral and vegetative regulation. RESULTS: 24 hours before operation IHD patients became anxious, coronary insufficiency and arrhythmia aggravated as shown by Holter ECG monitoring. Initial insufficiency of the antioxidant system, disturbances of the platelet-vascular hemostasis, hyperlipidemia and dyslipoproteinemia enhanced. Preoperative changes due to stress reaction affected the course of early intraoperative period. CONCLUSION: It is necessary to apply individual schemes of stress-limiting preoperative preparation in IHD patients.


Assuntos
Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Estresse Psicológico/etiologia , Adulto , Ansiedade/diagnóstico , Ansiedade/etiologia , Plaquetas/fisiologia , Ponte de Artéria Coronária/psicologia , Doença das Coronárias/metabolismo , Doença das Coronárias/psicologia , Eletrocardiografia Ambulatorial , Hemostasia , Humanos , Hiperlipidemias/etiologia , Hiperlipoproteinemias/etiologia , Metabolismo dos Lipídeos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Estresse Psicológico/diagnóstico , Fatores de Tempo
12.
Oncology ; 54(4): 270-4, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9216849

RESUMO

Based on encouraging reports of improved response rates with the use of dacarbazine (DTIC) in combination with recombinant interferon alpha-2a (rIFN-alpha-2a) in patients with metastatic malignant melanoma, we conducted a phase II study to determine the efficacy and feasibility of this treatment regimen. 31 patients were treated with an induction dose of rIFN-alpha-2a at 15 MIU/ m2 intravenously (i.v.) daily for 5 days per week for 3 consecutive weeks followed by a continuous maintenance dose of 10 MIU/m2 subcutaneously (s.c.) given 3 days per week; starting on day 22, in conjunction with rIFN-alpha-2a s.c., DTIC was started at a dose of 200 mg/m2 i.v. for 5 continuous days completing a 28-day cycle. Therapy was continued until progression was evidenced. Of the 29 evaluable patients, 7 (24.1%) achieved an objective response (complete plus partial remission) with the highest responses occurring in those patients assessed with pulmonary metastases. The median duration to treatment failure was 2.6 months, while the median survival was 6.9 months. Our data reveal that using rIFN-alpha-2a plus DTIC in combination does not yield better results than those achieved when using DTIC alone. However, 3 of the 7 responders experienced long-term survival ranging up to 42 months. Whether this benefit is achieved by the addition of rIFN-alpha-2a can only be answered by large randomized clinical trials. Conflicting results with some of the current literature are discussed.


Assuntos
Antineoplásicos/administração & dosagem , Dacarbazina/administração & dosagem , Interferon-alfa/administração & dosagem , Melanoma/tratamento farmacológico , Adulto , Idoso , Esquema de Medicação , Feminino , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas Recombinantes
13.
Acta Neurol Belg ; 97(1): 22-7, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9107341

RESUMO

Topographic differences in longlatency SSEP and flash VEP data are compared in 3 different psychiatric patient groups. Differences between schizophrenia and affective disorder are restricted to somatosensory P100 amplitude gradients along the antero-posterior axis. In contrast EP-differences between psychiatric patients and dementia are prominent, encompassing both late and early (< 100 ms) responses. Our flash P 2 and somatosensory P 3 data are in accordance with previous findings. Multi-modal positive responses with a latency of 40-80 ms are significantly increased in dementia. This facilitation suggests cortical dysfunction and/or subcortical gating impairment.


Assuntos
Córtex Cerebral/fisiopatologia , Potenciais Somatossensoriais Evocados , Transtornos Mentais/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Demência/fisiopatologia , Potenciais Evocados Visuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/fisiopatologia , Tempo de Reação , Esquizofrenia/fisiopatologia
15.
Fortschr Med ; 113(28): 393-6, 1995 Oct 10.
Artigo em Alemão | MEDLINE | ID: mdl-7498864

RESUMO

The incidence of malignant melanoma (MM) of the skin is on the increase. If the mortality of this disease is to be reduced, the identification of persons at risk, and early clinical diagnosis are of decisive importance. The prognosis depends on the stage of the disease and has improved over the last few decades. The present article provides an overview of the risk factors and discusses the latest guidelines for the diagnosis, treatment and follow-up, the aim of which is to make possible a uniform approach to the management of malignant melanoma.


Assuntos
Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Terapia Combinada , Diagnóstico Diferencial , Humanos , Melanoma/patologia , Melanoma/terapia , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco , Pele/patologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia
16.
Phys Rev B Condens Matter ; 42(12): 7429-7433, 1990 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9994886
17.
Arch Toxicol ; 63(3): 173-84, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2669681

RESUMO

In mammalian species, including man, N-acetyl-S-(2-hydroxyethyl)-L-cysteine (2-HEMA) is a common urinary metabolite of a large number of structurally different xenobiotic chemicals. It is a common urinary end product of glutathione pathway metabolism of a variety of chemicals possessing electrophilic properties and, in most cases, also a genotoxic potential. Five different chemically reactive intermediates, with different electrophilic properties, may be involved in the formation of 2-HEMA. An inventory of chemicals known to lead to the formation of 2-HEMA, or based on their chemical structure expected to do so, is presented. Furthermore, an attempt is made to evaluate the possibilities and limitations in terms of the potential use of urinary 2-HEMA as a tool in biomonitoring studies. Two other related, sulfur-containing urinary metabolites, i.e. N-acetyl-(S-carboxymethyl)-L-cysteine and thio-diacetic acid, are proposed as possible alternatives to urinary 2-HEMA. It is suggested that 2-HEMA might be seen as a potentially useful and sensitive signal parameter for the assessment of exposure of animals and man to a variety of electrophilic and therefore potentially toxic xenobiotic chemicals.


Assuntos
Acetilcisteína/análogos & derivados , Monitoramento Ambiental , Acetilcisteína/urina , Animais , Biomarcadores/urina , Poluição Ambiental , Humanos
18.
Xenobiotica ; 16(1): 21-33, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3946094

RESUMO

1,3-Dibromopropane (1,3-DBP) was administered i.p. in doses ranging from 5.6 to 54 mg to male Wistar rats. Four different mercapturic acids, viz. N-acetyl-S-3-bromopropyl-(MA I), N-acetyl-S-3-chloropropyl-(MA II), N-acetyl-S-2-carboxyethyl-(MA III) and N-acetyl-S-3-hydroxypropyl(-1-)cysteine (MA IV) were synthesized and identified as metabolites in urine by g.l.c.-mass spectrometry. 1,1,3,3-Tetradeutero-1,3-dibromopropane was used to study the mechanism of formation of the mercapturic acids in more detail. It was found that in the formation of MA IV a reactive episulphonium ion could be involved. Gas chromatographic quantification of the mercapturic acids (mercapturic acid assay) was correlated with a spectrophotometric thioether determination of the metabolites (thioether test). At doses up to 30 mg of 1,3-DBP, excretion of mercapturic acids was virtually complete in 24 h urine and amounted to about 19% of the dose (11.3% MA I, 4.9% MA II, 2.6% MA III and 0.2% MA IV). From excretion rate curves a half-time t1/2 was calculated as being about 4.5 h. A plateau in the dose-excretion curve was observed at 1,3-DBP doses higher than 40 mg, probably caused by glutathione depletion.


Assuntos
Propano/análogos & derivados , Acetilcisteína/urina , Animais , Cromatografia Gasosa , Relação Dose-Resposta a Droga , Cromatografia Gasosa-Espectrometria de Massas , Técnicas In Vitro , Masculino , Propano/administração & dosagem , Propano/metabolismo , Ratos , Ratos Endogâmicos , Sulfetos/urina , Fatores de Tempo
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