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1.
Orphanet J Rare Dis ; 17(Suppl 1): 170, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440056

RESUMO

Dunnigan syndrome, or Familial Partial Lipodystrophy type 2 (FPLD2; ORPHA 2348), is a rare autosomal dominant disorder due to pathogenic variants of the LMNA gene. The objective of the French National Diagnosis and Care Protocol (PNDS; Protocole National de Diagnostic et de Soins), is to provide health professionals with a guide to optimal management and care of patients with FPLD2, based on a critical literature review and multidisciplinary expert consensus. The PNDS, written by members of the French National Reference Center for Rare Diseases of Insulin Secretion and Insulin Sensitivity (PRISIS), is available on the French Health Authority website (in French). Dunnigan syndrome is characterized by a partial atrophy of the subcutaneous adipose tissue and by an insulin resistance syndrome, associated with a risk of metabolic, cardiovascular and muscular complications. Its prevalence, assessed at 1/100.000 in Europe, is probably considerably underestimated. Thorough clinical examination is key to diagnosis. Biochemical testing frequently shows hyperinsulinemia, abnormal glucose tolerance and hypertriglyceridemia. Elevated hepatic transaminases (hepatic steatosis) and creatine phosphokinase, and hyperandrogenism in women, are common. Molecular analysis of the LMNA gene confirms diagnosis and allows for family investigations. Regular screening and multidisciplinary monitoring of the associated complications are necessary. Diabetes frequently develops from puberty onwards. Hypertriglyceridemia may lead to acute pancreatitis. Early atherosclerosis and cardiomyopathy should be monitored. In women, polycystic ovary syndrome is common. Overall, the management of patients with Dunnigan syndrome requires the collaboration of several health care providers. The attending physician, in conjunction with the national care network, will ensure that the patient receives optimal care through regular follow-up and screening. The various elements of this PNDS are described to provide such a support.


Assuntos
Hipertrigliceridemia , Resistência à Insulina , Lipodistrofia Parcial Familiar , Lipodistrofia , Pancreatite , Doença Aguda , Feminino , Humanos , Hipertrigliceridemia/complicações , Lipodistrofia Parcial Familiar/diagnóstico , Lipodistrofia Parcial Familiar/genética , Lipodistrofia Parcial Familiar/terapia
2.
Clin Exp Allergy ; 48(7): 862-874, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29665158

RESUMO

BACKGROUND: Oral immunotherapy to peanut is effective in desensitizing patients but has significant side effects including anaphylaxis and gastrointestinal symptoms. In most protocols, peanut is administered in a vehicle food. OBJECTIVE: In an exclusively adolescent population, we tested a new approach using sealed capsules of peanut (gastrointestinal delivery oral immunotherapy or GIDOIT) to bypass the upper gastrointestinal tract. The primary aim was to assess the efficacy of the oral build-up phase of GIDOIT and the secondary aim to analyse its safety. METHODS: Adolescents with a history of a clinical allergic reaction after peanut ingestion were included in a 2-armed, parallel-design, individually randomized, double-blind, placebo-controlled, multicentre trial after a positive double-blind placebo-controlled oral food challenge (DBPCFC1). A central randomization centre used computer-generated tables to allocate treatments. Peanut (or placebo) capsules were ingested daily over a period of 24 weeks with increments every 2 weeks from 2 to 400 mg of peanut protein (pp). Primary outcome was tolerance of 400 mg of pp at DBPCFC2. RESULTS: Thirty patients were included between September 2013 and May 2014. At DBPCFC2, unresponsiveness to 400 mg of pp was achieved in 17/21 peanut group patients (2 withdrawn patients) and 1/9 in the placebo group (Intention-to-treat analysis, P < .001, absolute difference = 0.7, 95%IC 0.43 0.96). Oropharyngeal symptoms were equally frequent in both groups. No dysphagia or other signs of eosinophilic oesophagitis occurred. Digestive adverse events (AE) were more frequent in the treated group (P = .02), but mild and without compliance issues. Only one severe advent event led to withdrawal in a patient who ingested twice the investigated treatment. Peanut-specific humoral immune responses were modulated. CONCLUSION: The GIDOIT protocol demonstrated clinical and immunological efficacy and had an acceptable level of safety with weak oropharyngeal symptoms, no dysphagia, mild digestive events and few severe systemic AE.


Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Arachis/efeitos adversos , Dessensibilização Imunológica , Trato Gastrointestinal/imunologia , Hipersensibilidade a Amendoim/imunologia , Hipersensibilidade a Amendoim/terapia , Administração Oral , Adolescente , Fatores Etários , Alérgenos/administração & dosagem , Biomarcadores , Criança , Dessensibilização Imunológica/métodos , Feminino , Humanos , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Masculino , Hipersensibilidade a Amendoim/diagnóstico , Prevalência , Resultado do Tratamento
3.
Radiat Prot Dosimetry ; 177(1-2): 168-172, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036340

RESUMO

Knowing the concentration of 226Ra in soil and of 222Rn in soil gas is important for the analysis of indoor radon data and the prediction of radon-prone areas. Except for soil Rn in Ardenne, the data concerning these two radionuclides in Belgian soils are very scarce. In the context of Master theses and international courses, students made 92 measurements of 226Ra in soil samples, 105 of 222Rn in soil gas, and 74 of soil permeability, a significant addition to the existing similar data. The data are analysed in relation with soil texture, geological units and indoor radon risk. There is no clear correlation between radium in soil and indoor radon risk, the most important factor of risk being soil permeability.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos , Rádio (Elemento)/análise , Radônio/análise , Poluentes Radioativos do Solo/análise , Bélgica , Permeabilidade , Medição de Risco
5.
Acta Clin Belg ; 69(1): 53-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24635400

RESUMO

Azole antifungals are a group of fungistatic agents that can be administered orally or parenterally. The determination of the concentrations of these antifungals (miconazole, fluconazole, ketoconazole, posaconazole, voriconazole, itraconazole, and its major active metabolite, hydroxy-itraconazole) in serum can be useful to adapt the doses to pharmacological ranges because of large variability in the absorption and metabolism of the drugs, multiple drug interactions, but also potential resistance or toxicity. A method was developed and validated for the simultaneous determination of these drugs in serum utilizing ultra-high pressure liquid chromatography and diode array detection (UHPLC-DAD). After a simple and rapid liquid-liquid extraction, the pre-treated sample was analysed on an UHPLC-DAD system (Waters Corporation(®)). The chromatographic separation was carried out on an Acquity BEH C18 column (Waters Corporation) with a gradient mode of mobile phase composed of acetonitrile and aqueous ammonium bicarbonate 10·0 M pH10. The flow rate was 0·4 ml/min and the injection volume was 5 µl. The identification wavelength varied according to the drug from 210 to 260 nm. The method was validated by the total error method approach by using an analytical validation software (e•noval V3·0 Arlenda(®)). The seven azole antifungals were identified by retention time and specific UV spectra, over a 13-minute run time. All calibration curves showed good linearity (r(2)>0·99) in ranges considered clinically adequate. The assay was linear from 0·05 to 10 mg/l for voriconazole, posaconazole, itraconazole, hydroxy-itraconazole, and ketoconazole, from 0·3 to 10 mg/l for fluconazole, and from 0·1 to 10 mg/l for miconazole. The bias and imprecision values for intra- and inter-assays were lower than 10% and than 15%, respectively. In conclusion, a simple, sensitive, and selective UHPLC-DAD method was developed and validated to determine seven azole antifungal drugs in human serum. This method is applicable to patient samples, and can be applied successfully to clinical applications and therapeutic drug monitoring.


Assuntos
Antifúngicos/sangue , Cromatografia Líquida de Alta Pressão , Antifúngicos/química , Monitoramento de Medicamentos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Acta Clin Belg ; 68(5): 359-67, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24579243

RESUMO

The objective of the present study was to verify if severe physical health problems frequently encountered in heroin addicts and the concomitant use of alcohol and legal or illegal drugs other than heroin influenced the pharmacokinetics of the major metabolites of heroin. We conducted a 90 minutes follow-up of the plasma concentrations of the pharmaceutical heroin, named diacetylmorphine (DAM), in patients recruited in a DAM assisted treatment centre. TADAM (Traitement Assisté par DiAcétylMorphine) aimed to compare the efficacy of heroin-assisted treatment (HAT) compared with methadone maintenance treatment (MMT) for heroin users considered as treatment resistant patients and who have severe physical and mental health problems. Eleven patients were recruited. Blood samples were collected at baseline and 15, 45 and 90 minutes after DAM administration. All patients received DAM by the "chasing the dragon" route. Plasma samples were analyzed by a previously described ultra-high pressure liquid chromatography coupled to tandem mass spectrometry (UHPLC/MS-MS) method. A principal component analysis (PCA) was performed and 8 metabolite concentrations ratios were calculated to evaluate the influence of various factors (DAM dose, patient pathologies, concomitant use of medications, methadone, street heroin, alcohol and cocaine) on heroin metabolite pharmacokinetics. It seemed to be not affected by the DAM dose, patient pathologies and the concomitant use of medications, methadone, street heroin and alcohol. Cocaine use was the only parameter which showed differences in heroin pharmacokinetics.


Assuntos
Dependência de Heroína/sangue , Heroína/metabolismo , Adulto , Alcoolismo/sangue , Cromatografia Líquida de Alta Pressão , Transtornos Relacionados ao Uso de Cocaína/sangue , Heroína/farmacocinética , Dependência de Heroína/tratamento farmacológico , Humanos , Drogas Ilícitas/sangue , Metadona/uso terapêutico , Pessoa de Meia-Idade , Entorpecentes/uso terapêutico , Tratamento de Substituição de Opiáceos , Análise de Componente Principal , Espectrometria de Massas em Tandem
7.
J Anal Toxicol ; 36(1): 25-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22290749

RESUMO

In Belgium, driving under the influence (DUI) of cannabis is prohibited and has severe legal consequences for the driver if the blood plasma concentration of Δ(9)-tetrahydrocannabinol (THC) exceeds 1 µg/L. A method to quantify low concentrations of THC and its hydroxylated (THC-OH) and carboxylated (THC-COOH) metabolites in plasma was developed for DUI but also for other applications. Ultra-high-performance liquid chromatography coupled to mass spectrometry seems to be a very convenient method to combine fast chromatographic separation and good sensitivity. The method was validated according to total error approach. Chromatographic separation was achieved in a 3-min total run time. The limits of quantitation were lower or equal to 1 µg/L for all compounds. The linearity of the method was acceptable in the validated range of concentrations (from 0.5 to 50 µg/L for THC, from 0.9 to 50 µg/L for THC-OH and from 1.1 to 100 µg/L for THC-COOH). The biases were lower than 13%, and the relative standard deviations for repeatability and intermediate precision did not exceed 15%. Lower and upper ß-expectation tolerance limits did not exceed the acceptance limits of 20% for concentrations higher than 2 µg/L for THC and THC-OH and higher than 4 µg/L for THC-COOH. The acceptance limits were 30% for THC and THC-OH concentrations lower than 2 µg/L and for THC-COOH concentrations lower than 4 µg/L.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Dronabinol/sangue , Espectrometria de Massas em Tandem/métodos , Dronabinol/metabolismo , Humanos , Limite de Detecção
8.
Diabetes Metab ; 38(1): 14-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22284547

RESUMO

AIMS: To assess the success of dental-implant treatment in patients with diabetes. BACKGROUND: Dental-implant treatment is an efficient means of replacing lost teeth. However, diabetes can be considered a relative contraindication for this type of treatment because of the slightly higher failure rate compared with populations without diabetes. RECOMMENDATIONS: Prerequisite selection of suitable diabetic patients, eradication of co-morbidities (poor oral hygiene, cigarette-smoking, periodontitis), stabilization of glycaemic control (HbA(1c) at around 7%) and preventative measures against infection can increase the success of dental implantation in diabetic patients to a satisfactory rate of 85-95%. CONCLUSION: Implant surgery is never a matter of urgency; thus, diabetes patients with the best chances of success should be conjointly selected and prepared by both dental and diabetes clinicians.


Assuntos
Glicemia/metabolismo , Implantes Dentários , Diabetes Mellitus Tipo 2 , Hemoglobinas Glicadas/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/cirurgia , Feminino , Humanos , Masculino , Osseointegração , Seleção de Pacientes , Periodontite/complicações , Perda de Dente , Resultado do Tratamento
9.
Transl Psychiatry ; 1: e55, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22833210

RESUMO

Pharmacological, genetic and expression studies implicate N-methyl-D-aspartate (NMDA) receptor hypofunction in schizophrenia (SCZ). Similarly, several lines of evidence suggest that autism spectrum disorders (ASD) could be due to an imbalance between excitatory and inhibitory neurotransmission. As part of a project aimed at exploring rare and/or de novo mutations in neurodevelopmental disorders, we have sequenced the seven genes encoding for NMDA receptor subunits (NMDARs) in a large cohort of individuals affected with SCZ or ASD (n=429 and 428, respectively), parents of these subjects and controls (n=568). Here, we identified two de novo mutations in patients with sporadic SCZ in GRIN2A and one de novo mutation in GRIN2B in a patient with ASD. Truncating mutations in GRIN2C, GRIN3A and GRIN3B were identified in both subjects and controls, but no truncating mutations were found in the GRIN1, GRIN2A, GRIN2B and GRIN2D genes, both in patients and controls, suggesting that these subunits are critical for neurodevelopment. The present results support the hypothesis that rare de novo mutations in GRIN2A or GRIN2B can be associated with cases of sporadic SCZ or ASD, just as it has recently been described for the related neurodevelopmental disease intellectual disability. The influence of genetic variants appears different, depending on NMDAR subunits. Functional compensation could occur to counteract the loss of one allele in GRIN2C and GRIN3 family genes, whereas GRIN1, GRIN2A, GRIN2B and GRIN2D appear instrumental to normal brain development and function.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/genética , Mutação/genética , Receptores de N-Metil-D-Aspartato/genética , Esquizofrenia/genética , Alelos , Criança , Estudos de Coortes , Feminino , Deleção de Genes , Humanos , Masculino , Família Multigênica/genética , Proteínas do Tecido Nervoso/genética
10.
Ann Endocrinol (Paris) ; 70(2): 107-12, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19345337

RESUMO

Transsphenoidal surgery is currently the first-line treatment of acromegaly. Remission is observed in 80 to 90% microadenomas, 50 to 60% non-invasive macroadenomas, and less than 20% invasive macroadenomas. Predictive factors include age, maximal size of the adenoma, cavernous sinus invasion, initial hormone levels and neurosurgeon's experience. Complications are rare, with about 5% definitive diabetes insipidus and 10% of new anterior pituitary hormone deficits. Somatostatin agonist pretreatment can be proposed as it decreases tumor volume in about 25% cases and might reduce the rate of immediate postsurgical complications; however, there is no obvious difference in surgical remission rate whether patients are pretreated or not. Debulking surgery can also be proposed in very large macroadenomas incompletely controlled by somatostatin agonists or resistant to medical treatment, as it was shown to facilitate somatostatin agonist efficacy in more than 50% cases.


Assuntos
Acromegalia/cirurgia , Procedimentos Neurocirúrgicos , Acromegalia/etiologia , Humanos , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/cirurgia , Somatostatina/agonistas
11.
J Gynecol Obstet Biol Reprod (Paris) ; 38(3): 242-5, 2009 May.
Artigo em Francês | MEDLINE | ID: mdl-19304411

RESUMO

The ovaries are a common metastatic site for breast cancer. The diagnosis and treatment of ovarian masses from a metastatic breast cancer are difficult. The complete resection of these metastatic masses seems to give a benefit in terms of global survival. This benefit depends on the residual tumoral volume and on the free interval between initial breast cancer diagnosis and apparition of the metastatic ovarian masses. We discuss the treatment of a patient with ovarian metastasis as first sign of a metastatic breast cancer.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Lobular/patologia , Carcinoma Lobular/secundário , Neoplasias Ovarianas/secundário , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/sangue , Carcinoma Lobular/tratamento farmacológico , Ciclofosfamida/uso terapêutico , Epirubicina/uso terapêutico , Feminino , Fluoruracila/uso terapêutico , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Neoplasias Ovarianas/tratamento farmacológico
12.
Gynecol Obstet Fertil ; 35(7-8): 654-7, 2007.
Artigo em Francês | MEDLINE | ID: mdl-17567523

RESUMO

Acute myocardial infarction is an un-frequent event during pregnancy. It clearly causes an increase in both maternal and fetal mortality. We describe a case of pregnancy complicated during the second trimester by an acute myocardial infarction witch was treated by percutaneous transluminal coronary angioplasty combined with stenting. The challenge involved in managing this condition during pregnancy is briefly discussed.


Assuntos
Angioplastia com Balão , Infarto do Miocárdio/complicações , Infarto do Miocárdio/cirurgia , Complicações Cardiovasculares na Gravidez/cirurgia , Stents , Adulto , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez
13.
Acta Clin Belg ; 61 Suppl 1: 54-6, 2006.
Artigo em Francês | MEDLINE | ID: mdl-16700153

RESUMO

In order to achieve the harmonization of validation strategies, the interpretation of several validation criteria is proposed. Furthermore, a simple and visual decision tool to assess the validity of an analytical procedure is described: the accuracy profile based on the estimation of the total error of the measurements. This profile build with beta-expectation tolerance intervals can also compute with efficiency the uncertainty related to the results of a laboratory, which is an essential parameter for the accreditation of laboratories under ISO 17025.


Assuntos
Acreditação , Laboratórios/normas , Incerteza , Padrões de Referência
14.
Rev Med Liege ; 60(9): 724-8, 2005 Sep.
Artigo em Francês | MEDLINE | ID: mdl-16265967

RESUMO

The results of heroin analysis from seizures in the Liege area during the last two years are presented in this article. Between January 2003 and January 2005, 50 samples were analysed in the Laboratory of Clinical Toxicology and Forensic Toxicology of the University of Liege. Mean heroin concentration was 14,7%. Noscapine and papaverine, other opium alcaloïds, were simultaneously present with heroin. As diluents, we only identified caffein and acetaminophen.


Assuntos
Analgésicos Opioides/química , Heroína/química , Aplicação da Lei , Acetaminofen/análise , Analgésicos não Narcóticos/análise , Cafeína/análise , Estimulantes do Sistema Nervoso Central/análise , Cromatografia Líquida de Alta Pressão , França , Noscapina/análise , Papaverina/análise
15.
J Anal Toxicol ; 28(2): 138-40, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15068570

RESUMO

This paper presents a case of fatal overdosage due to an accidental massive administration (750 mg instead of 170 mg) of cisplatin, an anticancer agent, to a 63-year-old patient suffering from lymphoma. Platinum was measured in various postmortem samples by means of inductively coupled plasma mass spectrometry. Heart and peripheral blood concentrations of platinum were 1515 and 1253 micro g/L, respectively. Concentrations in urine and bile were 1038 and 501 micro g/L, respectively. Renal dialysis was started immediately after the end of cisplatin perfusion, when the mistake was noticed, but the patient deceased at day 16, presenting renal and hepatic insufficiency, ototoxicity, and pancytopenia.


Assuntos
Acidentes , Antineoplásicos/intoxicação , Cisplatino/intoxicação , Antineoplásicos/metabolismo , Causas de Morte , Cisplatino/metabolismo , Overdose de Drogas , Evolução Fatal , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade
16.
J Virol Methods ; 91(2): 99-108, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11164491

RESUMO

A highly sensitive RT-PCR protocol able to detect potato virus Y (PVY) in pooled sample units (tubers) was developed. PVY-specific primers selected in the coat protein gene were found to amplify a 359 bp fragment from diluted crude extract of infected tubers. For the detection of the amplification products, a colorimetric detection procedure in microtiter plates was established. The amplicons are hybridized between a covalently linked capture probe and a specific biotinylated detection probe ELOSA tests. This detection method detects at least 50 pg of virus per reaction for the four cultivars tested. The RT-PCR-ELOSA assay was adapted to pooled units in order to increase the sample size while reducing the number of tests.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Potyvirus/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Solanum tuberosum/virologia , Primers do DNA , DNA Viral/análise , Plantas Tóxicas , Potyvirus/genética , Sensibilidade e Especificidade , Nicotiana , Transcrição Gênica
17.
J Antimicrob Chemother ; 34(6): 1051-8, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7730221

RESUMO

Cryptococcus neoformans is responsible for pulmonary and meningal infections in HIV patients. The lack of effective cellular cooperation caused by the low level of CD4+ cells, and the resistance of C. neoformans to phagocytosis allows growth and persistence of the yeast in the host. We describe here an in-vitro model of intracellular replication of C. neoformans inside J774-A.1 macrophages, and the determination of the intracellular antifungal activity of amphotericin B and fluconazole alone or in association with IFN-gamma. The maximum inhibitory effect was observed with one MIC of amphotericin B and 100 or 1000 IU/mL of IFN-gamma. amphotericin B alone (at 1 x MIC), or either 1 x or 50 x MIC of fluconazole in normal or IFN-gamma activated macrophages, did not eradicate the ingested yeast. A potential underlying mechanism of the synergy of amphotericin B in IFN-gamma primed macrophages was investigated by measurement of nitrite level and by use of the NO synthase competitive inhibitor, NG-monomethyl L-arginine (NMMA). One MIC of amphotericin B was able to activate the synthesis of nitrogen reactive intermediates in IFN gamma-primed macrophages. NMMA treated infected macrophages responded less well to IFN-gamma priming, resulting in a moderate inhibition in subsequent amphotericin B exposure.


Assuntos
Anfotericina B/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Interferon gama/farmacologia , Macrófagos/microbiologia , Animais , Células Cultivadas , Cryptococcus neoformans/metabolismo , Sinergismo Farmacológico , Fluconazol/farmacologia , Humanos , Macrófagos/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese
18.
Biochem Pharmacol ; 48(9): 1693-9, 1994 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-7980637

RESUMO

Since acyl glucuronides are known to undergo deconjugation, especially in the presence of human serum albumin (HSA), only a few reports have described their reversible binding to plasma proteins. The aim of this study was to investigate the reversible binding of R and S ketoprofen glucuronides to HSA by a rapid technique, such as ultraviolet circular dichroism. Binding of R ketoprofen glucuronide only induced an extrinsic Cotton effect at 340 nm. Scatchard plot analysis revealed that R ketoprofen and its glucuronide are bound to one site of albumin with an association constant of 28.1 x 10(4) and 6.1 x 10(4) M-1, respectively. Modification of one tyrosine residue by diisopropylfluorophosphate prevented the access of ligands to sites I and II of albumin, and also fully inhibited the binding of R ketoprofen and that of its conjugate. Displacement experiments with specific probes of albumin binding sites suggested that R ketoprofen and the glucuronide are bound to site II rather than site I. However, R ketoprofen was not displaced by its conjugate. S ketoprofen glucuronide is also bound to HSA, since it decreased the binding of the antipode conjugate. However, the binding of this metabolite to albumin did not induce an extrinsic Cotton effect large enough to determine the binding constants. D-Glucuronic acid did not bind to sites I or II of albumin. This moiety is likely responsible for the lower affinity of HSA for the R ketoprofen glucuronide when compared to that for R ketoprofen, due to the hydrophilicity and/or the bulkiness of this group.


Assuntos
Glucuronatos/química , Cetoprofeno/química , Albumina Sérica/química , Sítios de Ligação , Dicroísmo Circular , Glucuronatos/síntese química , Isoflurofato , Ligação Proteica , Estereoisomerismo
19.
J Chromatogr B Biomed Appl ; 654(1): 61-8, 1994 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-8004244

RESUMO

A stereoselective high-performance liquid chromatographic (HPLC) method was developed to study the in vitro glucuronidation of ketoprofen enantiomers by liver microsomes. The HPLC system consisted of a Superspher 100 RP 18 end-capped column eluted with a mixture of acetonitrile and 10 mM tetrabutylammonium bromide in 1 mM potassium phosphate adjusted to pH 4.3 (30:70, v/v). Ultraviolet detection was performed at a wavelength of 254 nm. The capacity factors of S-ketoprofen glucuronide, R-ketoprofen glucuronide and R,S-ketoprofen were 12.8, 14.5 and 18.1, respectively. Sample pretreatment consisted of protein precipitation in microsomal incubation suspensions and further purification on a Sep Pak C18 cartridge before injection onto the HPLC system. Quantitation was performed with standard glucuronides biosynthetized with immobilized microsomes and purified by semi-preparative HPLC. The linearity of the method between 1.25 and 25.0 micrograms ml-1 (coefficient of correlation greater than 0.999), the repeatability (coefficient of variation = 1.2%; n = 5), and recovery (within 85%) were tested. The limit of detection was 10 ng for each glucuronide injected. The in vitro glucuronidation of R- and S-ketoprofen was measured in liver microsomes from man and from various animal species (dog, rat, rabbit). For both enantiomers, dog presented the highest specific activity. In contrast, the lowest activity was found in rabbit. On the other hand, the formation ratio of the S- and R-glucuronides of ketoprofen was close to 1 in man, rat and rabbit, but was 4.5 in dog, thus indicating that the reaction was stereoselective in this species.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Glucuronatos/metabolismo , Cetoprofeno/metabolismo , Microssomos Hepáticos/metabolismo , Animais , Cães , Humanos , Masculino , Coelhos , Ratos , Ratos Wistar , Especificidade da Espécie , Estereoisomerismo
20.
Fish Physiol Biochem ; 13(5): 419-31, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24197078

RESUMO

Thermal acclimation may directly modify muscle metabolic capacities, or may modify them indirectly via effects upon physiological processes such as growth, reproduction or senescence. To evaluate these interacting effects, we examined the influence of thermal acclimation and acclimatization upon muscle metabolic capacities and tissue masses in 1 + stickleback, Gasterosteus aculeatus, in which confounding interactions between temperature and senescense should be absent. Furthermore, we examined the influence of thermal acclimation upon individual growth rate, muscle enzyme levels and tissue masses in 2 + stickleback sampled at the beginning of their final reproductive season. For 1 + stickleback, cold acclimation more than doubles mitochondrial enzyme levels in the axial muscle. Thermal acclimation did not change the condition of 1 + stickleback at feeding levels which could not maintain the condition of 2+ stickleback. Compensatory metabolic responses to temperature were not apparent in field acclimatized 1 + stickleback. The growth rate of 2 + stickleback was markedly affected by temperature: warm-acclimated fish generally lost mass even at very high levels of feeding (up to 78 enchytraid worms per day) while cold-acclimated fish gained mass. This suggests that warm temperatures accelerate the senescence of 2 + stickleback. Generally, muscle enzyme activities increased with growth rate. In axial muscle, the relationships between CS activity and growth rate differed with acclimation temperature. Independent of the influence of growth rate, CS activities were consistently higher in cold- than warm-acclimated 2 + stickleback, suggesting compensatory increases of CS activity with cold acclimation.

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