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1.
Autoimmun Rev ; 16(3): 223-230, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28137480

RESUMO

OBJECTIVE: This case control study assessed: 1) the relationship of systemic sclerosis (SSc) related to exposure to heavy metals; and 2) the risk of SSc related to occupational exposure in male and female patients. METHODS: From 2005 to 2008, 100 patients with a definite diagnosis of SSc were included in the study; 3 age, gender, and smoking habit matched controls were selected for each patient. All SSc patients and controls underwent detection and quantification of heavy metal traces in hair samples, using multi-element inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: SSc patients exhibited higher median levels of the following metals: antimony (p=0.001), cadmium (p=0.0003), lead (p=0.02), mercury (p=0.02), molybdenum (p=0.04), palladium (p<0.0001) and zinc (p=0.0003). A marked association between SSc and occupational exposure was further found for: 1) antimony (p=0.008) and platinum (p=0.04) in male patients; and 2) antimony (p=0.02), cadmium (p=0.001), lead (p=0.03), mercury (p=0.03), palladium (p=0.0003) and zinc (p=0.0001) in female patients CONCLUSION: The results show the impact of occupational risk factors in the development of SSc for: antimony, cadmium, lead, mercury, molybdenum, palladium and zinc. Thus, occupational exposure should be systematically checked in all SSc patients at diagnosis. Finally, the association between SSc and occupational exposure may be variable according to patients' gender.


Assuntos
Exposição Ambiental/efeitos adversos , Metais Pesados/efeitos adversos , Exposição Ocupacional/efeitos adversos , Escleroderma Sistêmico/etiologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Fatores de Risco
2.
Autoimmun Rev ; 13(2): 151-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24129037

RESUMO

INTRODUCTION: Systemic sclerosis (SSc) has complex pathogenesis and likely multifactorial causes. Environmental exposures have been suggested to play a role in SSc pathogenesis, including occupational exposure to pollutants and chemicals as well as use of drugs leading to modulation of immune response. Thus, this case-control study aimed to assess: the relationship between SSc and occupational exposure; and the risk of SSc related to occupational exposure in male and female patients. METHODS: From 2005 to 2008, 100 patients with a definite diagnosis of SSc were included in the study; 3 age, gender, and smoking habits matched controls were selected for each patient. A committee of experts evaluated blindly occupational exposure to crystalline silica, white spirit, organic solvents, ketones, welding fumes, epoxy resins, and pesticides; an occupational exposure score was calculated for all subjects. Our findings were compared with previous data in the literature. RESULTS: Increased ORs for SSc were found for: crystalline silica (p<0.0001), white spirit (p<0.0001), aromatic solvents (p=0.0002), chlorinated solvents (p=0.014), trichlorethylene (p=0.044), ketones (p=0.002) and welding fumes (p=0.021). Elevated risk associated with high final cumulative score in SSc was observed for: crystalline silica, white spirit, chlorinated solvents, trichlorethylene, aromatic solvents, any type of solvents, ketones and welding fumes. A marked association between SSc and occupational exposure was further found for: 1) crystalline silica, chlorinated solvents, trichloroethylene, white spirit, ketones and welding fumes in male patients; and 2) white spirit, aromatic solvents, any type of solvent and ketones in female patients. Finally, we did not find an association between SSc and: 1) the use of drugs that have been speculated to play a role in SSc onset (anorexigens, pentazocine, bromocriptine, l-tryptophan); 2) implants - that are prosthesis, silicone implants, and contact lenses; and 3) dyeing hair. In the literature, SSc has been associated with occupational exposure to silica and solvents, while the association between SSc and specific organic solvents and welding fumes has been anecdotally reported. CONCLUSION: The following occupational factors have an impact in the development of SSc: crystalline silica, white spirit, aromatic solvents, chlorinated solvents, trichlorethylene, ketones and welding fumes. The risk of SSc appears to be markedly associated with high cumulative exposure. Finally, the association between SSc and occupational exposure may be variable according to gender.


Assuntos
Exposição Ocupacional , Escleroderma Sistêmico/induzido quimicamente , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Dióxido de Silício/toxicidade , Solventes/toxicidade
3.
Neurogastroenterol Motil ; 25(8): 694-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23663508

RESUMO

BACKGROUND: Incretin hormones [glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP)] released by the gut modulate gastrointestinal motility and influence gastric emptying (GE). Abnormal secretion or sensitivity to these hormones could contribute to the pathogenesis of gastroparesis. The aim of this study was to investigate incretin hormone secretion during a prolonged oral glucose load in non-diabetic patients with documented idiopathic gastroparesis. METHODS: Fifteen patients referred for digestive postprandial discomfort with delayed GE demonstrated by a (13) C-labeled octanoate breath test were included and compared with 10 healthy controls. A 75 g oral glucose load was performed, with blood samplings every 30 min for 5 h, to determine glucose, insulin, GIP, and GLP-1 blood levels. KEY RESULTS: Fasting GIP concentration was significantly higher in the patient group (56.1 ± 5.8 pg mL(-1) vs 29.9 ± 7.7 pg mL(-1), P =0.012). Postglucose load GIP concentrations were also significantly elevated in patients with gastroparesis, whereas GLP-1 concentrations during fasting and postglucose load conditions were not different to those of healthy controls. Moreover, glucose tolerance during glucose load was abnormal in patients, combining hyperglycemic insulin resistance and hyperinsulinism patterns, while fasting values for glycemia, insulin sensitivity, and insulin concentrations were normal. CONCLUSIONS & INFERENCES: Patients with idiopathic gastroparesis exhibit abnormal GIP levels associated with impaired insulin sensitivity during oral glucose load. Further studies are needed to establish the involvement of these defects in the pathophysiology of gastroparesis.


Assuntos
Polipeptídeo Inibidor Gástrico/metabolismo , Gastroparesia/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Glucose/administração & dosagem , Resistência à Insulina/fisiologia , Administração Oral , Adulto , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Feminino , Esvaziamento Gástrico/efeitos dos fármacos , Esvaziamento Gástrico/fisiologia , Polipeptídeo Inibidor Gástrico/sangue , Gastroparesia/diagnóstico , Humanos , Incretinas/sangue , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Período Pós-Prandial/efeitos dos fármacos , Período Pós-Prandial/fisiologia
5.
J Anal Toxicol ; 27(2): 113-7, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12670007

RESUMO

A case of fatal suicidal bentazon poisoning is presented along with a description of the different analytical methods involved. A 56-year-old farmer was examined by the family doctor 1 h after voluntarily ingesting 500 mL of FIGHTER (bentazon, 480 g/L water). He presented a Glasgow score of 15, polypnea, diarrhea, and vomiting. During transport by ambulance to the hospital, he tossed, sweated, and suddenly presented breathing difficulty followed by heart failure. Tracheal intubation was impossible (H1.5) despite use of different diameter cannulas because of extreme general muscle rigidity. All attempts at resuscitation failed, and the patient died within 2 h postingestion. Blood and urine samples were taken just before death. General basic and neutral drug screening by high-performance liquid chromatography-diode-array detection and gas chromatography-nitrogen-phosphorus detection showed no strychnine or other drugs or toxics except for citalopram (< 0.1 mg/L) and bentazon, but this weak acidic molecule (pKa3.3) was badly extracted in alkaline conditions. Plasma and urine levels, measured after acidic extraction, protein precipitation, or simple dilution, were 1500 and 1000 mg/L, respectively. Bentazon (M.W. 240) was confirmed by its basic mass spectrum (ESI-, m/z 239, 197, 175, 132) or by that of methylated derivative (El+, m/z 254, 212, 175). An hydroxylated metabolite (ESI-, m/z 255, 213, 191, 148; El+, m/z 284, 242, 163) and the N1-glucuronide conjugate of bentazon (ESI-, m/z 415, 239) were also detected in urine. (Quantitation ions are underlined.) This first case of bentazon poisoning with available analytical data revealed the high toxicity of this compound after large dose ingestion with early and heavy symptoms such as muscle rigidity probably related to muscular toxicity. Comparison with another nonfatal case and with toxicological data on animals is discussed.


Assuntos
Benzotiadiazinas/intoxicação , Herbicidas/intoxicação , Suicídio , Benzotiadiazinas/sangue , Benzotiadiazinas/urina , Cromatografia Líquida de Alta Pressão , Herbicidas/sangue , Herbicidas/urina , Humanos , Masculino , Pessoa de Meia-Idade
6.
J Clin Endocrinol Metab ; 88(3): 1107-11, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12629092

RESUMO

The follow-up of patients with papillary and follicular thyroid carcinoma after thyroidectomy and radioiodine ablation is mainly based on serum thyroglobulin (Tg) level deter-mination. The positive predictive value (PPV) of serum Tg level after thyroid hormone withdrawal, measured during the first 6-12 months of follow-up (initial off L-T(4) Tg), was studied in 256 consecutive differentiated thyroid cancer patients. All underwent a total thyroidectomy and 3.7 GBq (131)I ablation; 37 patients had an elevated initial off L-T(4) Tg level. This study focuses on these 37 patients, 9 of whom had a clinical recurrence. The present data confirm that in this selected cohort of patients, 74-185 MBq (131)I-total body scan (TBS) has no clinical interest in the initial work-up and during the subsequent follow-up because it was negative in all patients, except in one with recurrent disease. The PPV of initial serum off L-T(4) Tg level above 5 ng/ml and 10 ng/ml was 42% and 53%, respectively; this PPV was only 50% at the time of recurrence or subsequent control. This relatively low PPV is related to the low recurrence rate in this series of patients, despite a prolonged follow-up, and to the subsequent decrease of serum Tg level in 14 of 37 (38%) patients in the absence of any further treatment. In contrast, the PPV of the increasing slope of serum Tg levels obtained after thyroid hormone withdrawal (83%) was excellent. In conclusion, we confirm that (131)I-TBS has a limited interest for the follow-up of thyroid cancer patients. Follow-up should rely on serum Tg level and prognostic parameters; however, initial serum Tg may be produced by thyroid tissues of various significance, an increase at two consecutive determinations indicating disease progression and a decrease being related to late effects of therapy. The best PPV is brought by the slope of serum Tg levels.


Assuntos
Adenocarcinoma Folicular/sangue , Carcinoma Papilar/sangue , Tireoglobulina/sangue , Hormônios Tireóideos/uso terapêutico , Neoplasias da Glândula Tireoide/sangue , Adenocarcinoma Folicular/terapia , Adolescente , Adulto , Idoso , Carcinoma Papilar/terapia , Feminino , Seguimentos , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias da Glândula Tireoide/terapia
8.
Int J Clin Pharmacol Ther ; 39(8): 344-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11515709

RESUMO

Reactions between cisplatin or its aquated species and L-cysteine (L-cys) or glutathione (GSH) were studied in vitro using liquid chromatography on-line with inductively coupled plasma mass spectrometry (LC-ICPMS) and/or electrospray ionization mass spectrometry (LC-MS) in order to obtain information on the mechanisms occurring in treated patients. Reaction between cisplatin and L-cys yielded initially 4 adducts of which only 2 were stable and detectable after 24 hours incubation; their structures corresponded to bis-platinum cysteinyl adducts. Reaction of cisplatin with GSH proceeded via the formation of at least 11 glutathione-platinum adducts (G1 - G11) which underwent parallel reactions within 24 hours of incubation, probably to form higher molecular weight species. Of the 11 adducts, only 2, G3 and G7, whose structures correspond to [Pt(NH3)2Cl]2(SG) and [Pt(NH3)2OH]2(SG) were still present in the reaction mixture after 24 hours incubation. This study shows that GSH, and to a lesser extent L-cys, incubated with cisplatin in vitro forms unstable and reactive platinum compounds and that LC-ICPMS and LC-MS are 2 complementary techniques suitable for the study of organometallic compounds.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Cisteína/química , Adutos de DNA , Glutationa/química , Antineoplásicos/química , Cromatografia Líquida , Cisplatino/química , Técnicas In Vitro , Espectrometria de Massas por Ionização por Electrospray/métodos
9.
J Inorg Biochem ; 84(1-2): 129-35, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11330471

RESUMO

The initial rates of reactivity of oxaliplatin, its metabolites Pt(dach)Cl2 and Pt(dach)(OH2)2(2+) with guanosine and L-met in water, NaCl and phosphate were compared. Versus guanosine, the most reactive molecule was Pt(dach)(OH2)2(2+), about 40 fold that of oxaliplatin, the least reactive was Pt(dach)Cl2, Versus L-met, Pt(dach)(OH2)2(2+), was also the most reactive species but only about 2 fold more reactive than Pt(dach)Cl2 and oxaliplatin. Pt(dach)(OH2)2(2+) was approximately 3 fold less reactive versus methionine than guanosine whereas oxaliplatin and Pt(dach)Cl2 were about seven fold more reactive versus methionine than guanosine. Thus, the three platinum compounds oxaliplatin, Pt(dach)Cl2 and Pt(dach)(OH2)2(2+) react with L-met but only the Pt(dach)(OH2)2(2+) has a high reactivity with guanosine. Oxaliplatin, which is stable in water, has to be transformed in the presence of chloride in chloro-derivatives which are aquated to become active particularly versus guanosine. These data demonstrate that oxaliplatin has similarities with cisplatin in terms of chloride versus water coordination and in terms of dependence on chloride concentration for transformations.


Assuntos
Guanosina/metabolismo , Metionina/metabolismo , Compostos Organoplatínicos/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Técnicas In Vitro , Cinética , Compostos Organoplatínicos/química , Oxaliplatina
10.
Biol Trace Elem Res ; 83(3): 191-206, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11794512

RESUMO

The transport and uptake of the most common Se compounds, selenate (SeO42-), selenite (SeO3(2-)), selenomethionine, and selenocystine, were investigated using confluent monolayers of Caco-2 cells, a human carcinoma cell line. Comparative measurements were performed in the absorptive (apical to basolateral side) and exsorptive (basolateral to apical side) directions. Apparent permeability coefficients (Papp), calculated from transport experiments in the absorptive direction, showed increasing values in the following rank order: about 1 x 10(6) cm/s < mannitol < SeO3(2-) < or = selenocystine < selenomethionine < SeO4(2-) < or = about 16 x 10(4) cm/s. The ratios of the Papp measured in the absorptive versus exsorptive directions indicated that only the organic forms presented a net polarized transport (Papp ratio >> 1), suggesting the presence of a transcellular pathway. No significant excretion was observed. The transport of selenomethionine was inhibited by its sulfur analog, methionine, suggesting a common transport mechanism. In contrast, an inhibition of the transport of selenocystine by cysteine was not observed. From the two substrates tested, sulfate and thiosulfate, only thiosulfate inhibited the transport of SeO4(2-) . This effect was also observed for SeO32- (i.e., was unspecific), which questioned the assertion of a common transport for sulfate and SeO4(2-) and may confirm the paracellular pathway of SeO42- suggested by the Papp ratio of about 1. The addition of glutathione (GSH) in large excess had no consequence on the passage of SeO3(2-) but strongly increased the uptake (about fourfold). The liquid chromatography - mass spectrometry (LC-MS) data showed that, in the ionic condition of incubation medium, GSH promptly reduced SeO3(2-) (< or = 2 min) in its elemental form Se0, which cannot ascribe to selenodiglutathione a direct role in the effect of GSH.


Assuntos
Cistina/análogos & derivados , Compostos de Selênio/metabolismo , Selênio/metabolismo , Transporte Biológico , Células CACO-2 , Cisteína/metabolismo , Cistina/metabolismo , Glutationa/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Manitol/farmacocinética , Metionina/metabolismo , Compostos Organosselênicos/metabolismo , Ácido Selênico , Selênio/farmacocinética , Compostos de Selênio/farmacocinética , Selenometionina/metabolismo , Sulfatos/metabolismo , Células Tumorais Cultivadas
11.
Drug Metab Dispos ; 28(11): 1379-84, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11038167

RESUMO

This article deals with the fate of oxaliplatin 1 and 3 h after its i.v. administration (130 mg/m(2)) to three patients. Its binding to plasma proteins and penetration into red blood cells were monitored by chromatography on-line with inductively coupled plasma mass spectrometry. Oxaliplatin biotransformations in plasma ultrafiltrate (PUF) and in urine were studied by chromatography coupled to inductively coupled plasma mass spectrometry or to electrospray ionization mass spectrometry. In plasma, four platinum (Pt) compounds were found. The peaks at 200 and 160 kDa corresponding to gamma-globulins contained 40% of the Pt bound; the peak at 60 kDa corresponding to albumin contained 40% of the Pt found. The peak <2 kDa could correspond to oxaliplatin, to its degradation products, or to adducts between Pt compounds and low-molecular-weight species such as glutathione, L-methionine, and L-cysteine. In PUF and urine, oxaliplatin itself, its degradation products, Pt(dach)Cl(2), [Pt(dach)(OH(2))Cl](+), and species that have the same retention times as Pt(dach)(methionine) and [Pt(dach)](2)(glutathione) were found. One hour after infusion, oxaliplatin in PUF and urine represented 12 and 50% of the total Pt, respectively. Three hours after infusion, oxaliplatin, undetectable in PUF, represented 10% of total Pt in urine. Inside red blood cells, two Pt compounds were found. The Pt peak at 60 kDa corresponding to hemoglobin and the peak <2 kDa corresponding to low-molecular species contained, respectively, 60% and 40% of Pt found. This study demonstrates that in the first hours after its infusion, oxaliplatin, in addition to other Pt compounds, is present in plasma and urine and that Pt is bound to albumin, gamma-globulins, and hemoglobin.


Assuntos
Antineoplásicos/farmacocinética , Neoplasias/tratamento farmacológico , Compostos Organoplatínicos/farmacocinética , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Biotransformação , Proteínas Sanguíneas/metabolismo , Cromatografia Líquida , Humanos , Infusões Intravenosas , Espectrometria de Massas , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/metabolismo , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina
12.
Biochim Biophys Acta ; 1493(1-2): 279-83, 2000 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-10978539

RESUMO

The adenylyl cyclase type VI gene expressed in human normal thyroid tissue was cloned and sequenced. The cDNA sequence (6463 nt) is susceptible to code for a 1168 aa protein. Northern blots using specific probes showed that the expression of adenylyl cyclase type VI gene was significantly higher in one hyperfunctioning thyroid tumor than in normal thyroid tissue, in one follicular cold adenoma or in one papillary carcinoma.


Assuntos
Adenilil Ciclases/genética , Glândula Tireoide/enzimologia , Adenoma/enzimologia , Adenilil Ciclases/química , Adenilil Ciclases/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Clonagem Molecular , DNA Complementar/química , Éxons , Expressão Gênica , Humanos , Íntrons , Dados de Sequência Molecular , Neoplasias da Glândula Tireoide/enzimologia
14.
J Clin Endocrinol Metab ; 85(1): 175-8, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10634383

RESUMO

A diagnostic iodine-131 (131I) total body scan (TBS) is usually recommended 6 to 12 months after thyroid ablation for differentiated thyroid carcinoma. Its usefulness was evaluated in 256 consecutive patients treated and followed up at the Institut Gustave Roussy for papillary (n = 200), well differentiated (n = 27), or poorly differentiated (n = 29) follicular thyroid carcinomas. All patients underwent a near-total or total thyroidectomy and 131I ablation with 3.7 GBq (100 mCi). No TBS was performed before 131I ablation. The TBS performed after the administration of 131I to destroy the thyroid remnants showed uptake (<2%) limited to the thyroid bed. A diagnostic 131I-TBS was obtained after withdrawal of T4 treatment, with either 74 MBq (2 mCi; n = 82) or 185 MBq (5 mCi; n = 174), 6 to 12 months after initial treatment, with serum thyroglobulin (Tg) determination. No interference in the Tg assay was found in these 256 patients. Uptake in the thyroid bed was not detected (total ablation) in 236 patients, was visible but too low to be measured in 19 patients, and attained 1% in only 1 patient. No uptake was found outside the thyroid bed. The serum Tg level, once thyroid hormone treatment had been withdrawn, was below 1 ng/mL in 210 patients, ranged from 1-10 ng/mL in 31 patients, and was above 10 ng/mL in 15 patients. A 131I-TBS performed with 3.7 GBq in nine patients with a Tg level above 10 ng/mL, showed foci of uptake outside the thyroid bed in three patients; lung metastases were demonstrated by a CT scan in another patient, and palpable lymph node metastases were found in one patient. In conclusion, a diagnostic 131I-TBS with 74-185 MBq performed 1 yr after thyroid ablation demonstrated no abnormal uptake; it did not correlate with results of Tg determination and only confirmed the completeness of thyroid ablation. The serum Tg level obtained after withdrawal of T4 treatment permits the selection of patients with a Tg level exceeding 10 ng/mL, for scanning with 3.7 GBq (100 mCi).


Assuntos
Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Terapia de Reposição Hormonal , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Cintilografia , Tireoglobulina/metabolismo , Glândula Tireoide/patologia , Hormônios Tireóideos/uso terapêutico , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia
15.
Presse Med ; 28(23): 1231-4, 1999 Jun 26.
Artigo em Francês | MEDLINE | ID: mdl-10420887

RESUMO

BACKGROUND: Neuroendocrine tumors can occur in patients with hereditary syndromes predisposing to multiple endocrine neoplasia (MEN) and Von Hippel-Lindau disease (VHL). CASE REPORTS: We report the cases of three men with pheochromocytomas, one with an associated neuroendocrine tumor of the pancreas. In one case, diagnosis was suggested by the familial context of VHL in the patients father. In the two other cases, the bilateral character of the pheochromocytoma, and in one case the associated pancreatic neuroendocrine tumor led to the diagnosis of VHL. Systematic biological surveillance gave the diagnosis of contralateral pheochromocytoma in two cases. Search for associated tumoral lesions led to the diagnosis of hemangioblastoma of the cerebellum in two patients and pancreatic cyst in the third. No renal or retinal lesions were observed. Molecular study of the VHL gene evidenced point nonsense mutation of the gene in all three patients, involving codon 184 in two and codon 167 in the third (identical to the proband case). Systematic investigations in the families of the two other patients remains to be completed. CONCLUSION: The diagnosis of HVL disease should be suggested in case of familial pheochromocytoma and/or bilateral localizations, but also in case of neuroendocrine tumors of the pancreas associated with another cardinal lesion of the disease. Early screening and treatment of this potentially fatal disease is essential.


Assuntos
Doença de von Hippel-Lindau/complicações , Adolescente , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Adulto , Criança , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/diagnóstico por imagem , Linhagem , Feocromocitoma/diagnóstico , Feocromocitoma/etiologia , Ultrassonografia , Doença de von Hippel-Lindau/genética
16.
Eur J Endocrinol ; 140(5): 434-7, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10229910

RESUMO

OBJECTIVE: Amine precursor uptake and decarboxylation is a classical feature of gastroenteropancreatic (GEP) neuroendocrine tumors (NET). Production of catecholamines was studied in GEP NET and non-NET patients. DESIGN: A cross-sectional study was undertaken. METHODS: We studied catecholamine and metabolite secretion in 115 consecutive GEP NET patients and in 20 patients with non-NET. After specific extraction, vanilmandelic acid, homovanilic acid, catecholamines (norepinephrine, epinephrine, dopamine) and methoxylated derivates (metanephrine, normetanephrine, methoxytyramine) in urinary extracts were analyzed by high performance liquid chromatography. Results were indexed to the 24-h urinary creatinine levels. RESULTS: Among the 115 patients with NET, 9 (8%) had an increase of at least one urinary catecholamine or metabolite; in 7 out of the 9 the increase was slight being less than twice the upper value of the normal range. Elevated urinary dopamine (3 patients), methoxytyramine (6 patients), norepinephrine (2 patients) and normetanephrine (2 patients) were found. No increased urinary excretion of epinephrine nor metanephrine was observed. An adrenal mass existed in one of these nine patients but metaiodobenzylguanidine scintigraphy was negative as was immunohistochemistry for epithelial markers. None of the 20 patients with non-NET demonstrated an increased excretion of catecholamine or metabolites. No relationships were found between catecholamine and metabolite excretions and patients' tumor and treatment characteristics. CONCLUSION: Production of catecholamines and metabolites is a rare event in GEP NET patients. Histological results, including positive immunohistochemistry for epithelial markers may help to diagnose GEP NET.


Assuntos
Catecolaminas/biossíntese , Neoplasias Gastrointestinais/metabolismo , Tumores Neuroendócrinos/metabolismo , Neoplasias Pancreáticas/metabolismo , Adulto , Idoso , Catecolaminas/urina , Estudos Transversais , Feminino , Neoplasias Gastrointestinais/urina , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/urina , Neoplasias Pancreáticas/urina
17.
Biopharm Drug Dispos ; 20(2): 107-16, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10206326

RESUMO

The activity of platinum compounds is dependent on nucleophile substitution reactions. In this paper, we study the reactivity of L-met with carboplatin, oxaliplatin and cisplatin by following with HPLC-UV the concentration of L-met and by characterizing the resulting adducts with LC-MS. In the absence of NaCl, in water, the initial rate at which L-met concentration decreases with cisplatin, oxaliplatin and carboplatin is 0.25 +/- 0.007, 0.057 +/- 0.01 and 0.17 +/- 0.02 mM h(-1), respectively. In phosphate buffer this rate is 0.056 +/- 0.009 for cisplatin, 0.019 +/- 0.001 and 0.13 +/- 0.02 for carboplatin and oxaliplatin, respectively. Reactions of L-met with cisplatin occurred via its conversion into monoaqua species in water and into phosphato-derivatives (AP) in phosphate buffer but finally the same methionine-platinum adducts M2 [(NH3)2(met)]Pt, M4 and M5 [(met)2]Pt were characterized. Reaction of carboplatin with L-met occurred via the formation of M0 [(NH3)2(met)(CBDCA)]Pt whose structure is consistent with the direct interaction of L-met with carboplatin. However, the same final products as those found with cisplatin were characterized. The reaction of oxaliplatin with L-met proceeded through a mechanism similar to that of carboplatin to give M7 [(met)(DACH)]Pt. In the presence of NaCl, cisplatin directly reacted with L-met to yield at least five methionine-platinum adducts. The reaction of carboplatin gave the same adducts suggesting its transformation into cisplatin. The reaction of oxaliplatin with L-met occurred via the formation of aquated species A [(OH)(Cl)(DACH)]Pt which readily underwent reaction with L-met to form M6 [(met)(Cl)(DACH)]Pt and M7. This study shows that the reactivity of cisplatin, carboplatin and oxaliplatin is dependent on the media in which they occur. The discrepancy between their reactions with L-met could partly explain their therapeutic differences.


Assuntos
Antineoplásicos/química , Carboplatina/química , Cisplatino/química , Metionina/química , Compostos Organoplatínicos/química , Soluções Tampão , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Espectrometria de Massas , Oxaliplatina , Fosfatos , Espectrofotometria Ultravioleta , Água
18.
C R Acad Sci III ; 322(2-3): 205-13, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10196674

RESUMO

The thyroid gland is highly sensitive to radiation during childhood: the risk of thyroid tumours is increased for mean doses as low as 100 mGy and for higher doses, the risk increases linearly with the dose. Excess relative risk is important, being 7.7 for 1 Gy delivered to the thyroid gland during childhood. The risk of thyroid tumours is modified by several factors: a) age at exposure: in childhood, the risk decreases with increasing age at exposure and is not significant after 20 years; b) gender: females are two times more likely than males to develop thyroid tumours; c) genetic predisposition due to a defect in DNA repair mechanisms, and dietary and hormonal factors may modify the risk; d) the influence of fractionation and dose rate is not well established. Radioiodine 131 (1311) used for medical purposes has almost no tumourigenic effect on the adult thyroid gland. The consequences of the Chernobyl accident have clearly shown that the risk of thyroid cancer after exposure to 1311 in childhood is important, and that such exposure should be prevented by potassium iodine prophylaxis. RET/PTC rearrangements are found in 60-80% of papillary carcinomas and in 45% of adenomas occurring after radiation exposure. They are found in 5-15% of papillary carcinoma and in no follicular adenomas that occurred in the absence of radiation exposure.


Assuntos
Neoplasias Induzidas por Radiação , Segunda Neoplasia Primária/etiologia , Centrais Elétricas , Liberação Nociva de Radioativos , Neoplasias da Glândula Tireoide/etiologia , Adulto , Criança , Feminino , Humanos , Radioisótopos do Iodo/efeitos adversos , Masculino , Fatores de Risco , Ucrânia
19.
Br J Cancer ; 78(8): 1102-7, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9792158

RESUMO

Circulating neuron-specific enolase (NSE) and chromogranin A (CgA) were measured in 128 patients with neuroendocrine tumours (NET) to compare their sensitivity and specificity, to investigate factors associated with elevated serum levels and to determine the usefulness of these markers in the follow-up of NET patients. NSE (Cispack NSE, Cis Bio International, Gif-sur-Yvette, France; normal <12.5 microg l(-1)), and chromogranin A (CgA-Riact, Cis Bio International, normal <100 microg l(-1)) were measured in 128 patients without renal insufficiency. There were 99 patients with gastroenteropancreatic (GEP) NET, 19 with medullary thyroid carcinoma and ten with phaeochromocytoma. Fifty-three patients with non-NET were studied as controls. Serum NSE and CgA levels were elevated in 48 (38%) and 76 (59%) of the 128 NET patients respectively. In all groups of NET patients, CgA proved to be more sensitive than NSE. NSE and CgA had a specificity of 73% and 68% respectively. Immunostaining for NSE was positive in three out of eight controls with elevated CgA levels, whereas immunostaining for CgA and synaptophysin was negative in all cases. Elevated CgA levels were significantly associated with two independent parameters, namely the presence of other secretions (P = 0.0001) and a heavy tumour burden (P = 0.001). Elevated NSE levels were exclusively associated with poor tumour differentiation (P = 0.01). Among six patients with NET followed for 11-37 months, CgA appeared to be a better marker of tumour evolution than NSE. We suggest that CgA ought to be the only general marker screened in NET patients.


Assuntos
Biomarcadores Tumorais/sangue , Cromograninas/sangue , Neurônios/química , Fosfopiruvato Hidratase/sangue , Adolescente , Adulto , Idoso , Carcinoma/sangue , Carcinoma Medular/sangue , Cromogranina A , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos , Neoplasias Pancreáticas/sangue , Feocromocitoma/sangue , Sensibilidade e Especificidade , Neoplasias Gástricas/sangue , Neoplasias da Glândula Tireoide/sangue
20.
Cancer ; 83(3): 553-9, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9690549

RESUMO

BACKGROUND: Patients with thyroid microcarcinoma (TMC) have favorable long term prognoses. However, recurrences in the neck and distant metastases have been reported. The authors investigated independent factors associated with recurrence in an effort to define therapeutic guidelines. METHODS: Two hundred eighty-one patients (207 females, 74 males; mean age, 41.9 years) with a differentiated thyroid carcinoma < or = 1 cm in greatest dimension (mean size +/- standard deviation, 5.9+/-3.3 mm) were analyzed. The median follow-up time was 7.3 years. RESULTS: TMC diagnosis was incidental in 189 patients, and metastases were the first manifestation of the disease in the other 92 patients. Therapy included near-total thyroidectomy for 195 patients, lymph node dissection for 195, and therapeutic administration of radioiodine for 124. Eleven recurrences (3.9%) were observed 4.3+/-2.7 years (mean +/- standard deviation) after initial treatment: all had locoregional recurrence (4 in the thyroid bed and 7 in the lymph nodes), and in one of these the local recurrence was associated with lung metastases. Multivariate analysis showed that two parameters significantly influenced TMC recurrence, namely, the number of histologic foci (P < 0.002) and the extent of initial thyroid surgery (P < 0.01). Only 3.3% of patients with unifocal TMC treated with loboisthmusectomy had tumor recurrence. CONCLUSIONS: The recurrence rate for TMC appears to be low (3.9%). In the authors' view, loboisthmusectomy is the treatment of choice for patients with TMC when only one focus of cancer is found histologically, and total thyroidectomy is the optimal treatment for patients with multiple foci.


Assuntos
Carcinoma/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Carcinoma/mortalidade , Carcinoma/terapia , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/terapia
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