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1.
Eur Ann Otorhinolaryngol Head Neck Dis ; 139(5): 269-274, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35538001

RESUMEN

OBJECTIVES: To evaluate positive predictive values (PPVs) of magnetic resonance imaging (MRI) and ultrasound-guided fine-needle aspiration biopsy (UFNAB) in patients with isolated parotid swelling. MATERIAL AND METHODS: Observational study following the STARD guideline, based on a cohort of 212 patients from 18 to 93years of age, with isolated parotid swelling (malignant: 16.9%; benign: 83.1%), consecutively operated on between 2015 and 2020, after work-up including MRI and UFNAB in an otorhinolaryngology department of a university hospital. The main endpoint was PPV for diagnosis of benign tumor, malignant tumor and the most frequent etiology. Secondary endpoints were correlations between PPVs and clinical factors for malignancy, and the impact on PPV of various situations: dynamic analysis on MRI; diagnostic disagreement between MRI and UFNAB; and UFNAB PPV according to MRI diagnosis. RESULTS: PPVs for MRI and UFNAB were respectively 45.4% and 88.8% for malignant tumor, 89.6% and 46.9% for benign tumor, and 88.1% and 85.2% for pleomorphic adenoma (the most frequent etiology). Tumor fixation and history of head and neck radiation therapy PPVs were the only one higher than the MRI one for malignant tumor. MRI PPV did not differ between groups with or without dynamic analysis. PPV for malignant tumor, benign tumor and pleomorphic adenoma on MRI and UFNAB was respectively 42.8% and 33.3%, 42.8% and 100%, and 36.3% and 50% in case of diagnostic discordance. When MRI suggested malignant tumor, UFNAB PPV was 51.8% for malignant tumor, 67.7% for benign tumor, and 37.5% for pleomorphic adenoma; when MRI suggested benign tumor, it was 32.2% for malignant tumor, 91.5% for benign tumor, and 88.5% for pleomorphic adenoma; and, when MRI suggested pleomorphic adenoma, it was 23.5% for malignant tumor, 93.9% for benign tumor, and 92% for pleomorphic adenoma. CONCLUSION: Systematic association of UFNAB to MRI did not fundamentally improve diagnostic accuracy. UFNAB appeared most valuable in case of history of radiation therapy, in case of tumor fixation, and when MRI diagnosis was uncertain and/or suggested malignant tumor and/or the apparent diffusion coefficient (ADC) was low. The contribution of UFNAB when MRI suggested benign tumor or especially pleomorphic adenoma was more limited.


Asunto(s)
Adenoma Pleomórfico , Neoplasias de la Parótida , Adenoma Pleomórfico/diagnóstico por imagen , Adenoma Pleomórfico/cirugía , Adulto , Biopsia con Aguja Fina/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Neoplasias de la Parótida/patología , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad , Ultrasonografía Intervencional
3.
4.
5.
Mech Ageing Dev ; 106(3): 305-20, 1999 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-10100158

RESUMEN

The purpose of this study was to investigate the effects of hindlimb suspension (HS) on contractile properties of skeletal muscles of young and old rats and to determine the impact of electrical stimulation (ES) on the quality and degree of recovery of these muscles. After 21 days of HS, young soleus (SOL) muscle became faster, but there was no impact on young extensor digitorum longus (EDL) muscle. Twitch tension (Pt) decreased 61% in young and 70% in old SOL muscles. Specific tetanic tension (Po) decreased 53% in young and 64% in old SOL muscles, but again there was no impact on EDL muscle. After a 14-day period of recovery, contraction time (CT), half-relaxation time (RT1/2), Pt and Po returned to control group values in both young and old SOL muscles. Measurements of the contractile properties of young and old skeletal rat muscles showed ES sometimes to be beneficial but also sometimes to be harmful. A 14-day period of recovery, with or without ES, seemed sufficient for many variables to return to control group values.


Asunto(s)
Envejecimiento/fisiología , Suspensión Trasera/fisiología , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Animales , Fenómenos Biomecánicos , Estimulación Eléctrica , Femenino , Estudios de Seguimiento , Ratas , Ratas Sprague-Dawley
6.
J Med Chem ; 39(20): 3951-70, 1996 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-8831761

RESUMEN

Naphthalenic lignan lactone 3a (L-702,539), a potent and selective 5-lipoxygenase (5-LO) inhibitor, is extensively metabolized at two different sites: the tetrahydropyran and the lactone rings. Early knowledge of the metabolic pathways triggered and directed a structure-activity relationship study aimed toward the improvement of metabolic stability in this series. The best modifications discovered, i.e., replacement of the lactone ring by a nitrile group, replacement of the tetrahydropyran ring by a 6,8-dioxabicyclo[3.2.1]octanyl moiety, and replacement of the pendant phenyl ring by a 3-furyl ring, were incorporated in a single molecule to produce inhibitor 9ac (L-708,780). Compound 9ac inhibits the oxidation of arachidonic acid to 5-hydroperoxy-eicosatetraenoic acid by 5-LO (IC50 = 190 nM) and the formation of leukotriene B4 in human polymorphonuclear leukocytes (IC50 = 3 nM) as well as in human whole blood (IC50 = 150 nM). The good inhibitory profile shown by naphthalenenitrile 9ac is accompanied by an improved resistance to oxidative metabolism. In addition, 9ac is orally active in the functional model of antigen-induced bronchoconstriction in allergic squirrel monkeys (95% inhibition at 0.1 mg/kg).


Asunto(s)
Benzofuranos/química , Inhibidores de la Lipooxigenasa , Inhibidores de la Lipooxigenasa/química , Naftalenos/química , Nitrilos/química , Animales , Araquidonato 5-Lipooxigenasa/metabolismo , Ácido Araquidónico/metabolismo , Broncoconstricción/efectos de los fármacos , Estabilidad de Medicamentos , Humanos , Leucotrieno B4/biosíntesis , Leucotrieno B4/sangre , Leucotrienos/metabolismo , Inhibidores de la Lipooxigenasa/farmacología , Masculino , Microsomas Hepáticos/enzimología , Estructura Molecular , Naftalenos/farmacología , Neutrófilos/metabolismo , Nitrilos/farmacología , Oxidación-Reducción , Ratas , Ratas Sprague-Dawley , Saimiri , Relación Estructura-Actividad
7.
J Radiol ; 75(8-9): 427-31, 1994.
Artículo en Francés | MEDLINE | ID: mdl-7799285

RESUMEN

In this work, on 7 cases of spinal neurological, the authors analyse the use of imaging in the diagnosis and pretherapeutic approach, as well as for the post-operative follow-up. They insist mostly on the value of tomographic imaging methods, in particular: computed tomography, which allows the study of mineral structures, and determines the site of implant pedicle; magnetic resonance imaging important to precise the connections between tumor and spinal canal contents. They prove that other imaging methods still possess some interest, particularly standard X-ray, useful in estimating the characteristics of exostosis and identifying spinal lesions.


Asunto(s)
Imagen por Resonancia Magnética , Osteocondroma/diagnóstico por imagen , Compresión de la Médula Espinal/diagnóstico por imagen , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteocondroma/complicaciones , Osteocondroma/diagnóstico , Estudios Retrospectivos , Compresión de la Médula Espinal/diagnóstico , Compresión de la Médula Espinal/etiología , Neoplasias de la Columna Vertebral/complicaciones , Neoplasias de la Columna Vertebral/diagnóstico
8.
J Med Chem ; 37(8): 1153-64, 1994 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-8164257

RESUMEN

Leukotriene biosynthesis inhibitors have potential as new therapies for asthma and inflammatory diseases. The recently disclosed thiopyrano[2,3,4-cd]indole class of 5-lipoxygenase (5-LO) inhibitors has been investigated with particular emphasis on the side chain bearing the acidic functionality. The SAR studies have shown that the inclusion of a heteroatom (O or S) in conjunction with an alpha-ethyl substituted acid leads to inhibitors of improved potency. The most potent inhibitor prepared contains a 2-ethoxybutanoic acid side chain. This compound, 14d (2-[2-[1-(4-chlorobenzyl)-4-methyl-6-[(5-phenylpyridin-2-yl)methox y]- 4,5-dihydro-1H-thiopyrano[2,3,4-cd]indol-2-yl]ethoxy]-butanoic acid, L-699,333), inhibits 5-HPETE production by human 5-LO and LTB4 biosynthesis by human PMN leukocytes and human whole blood (IC50s of 22 nM, 7 nM and 3.8 microM, respectively). The racemic acid 14d has been shown to be functionally active in a rat pleurisy model (inhibition of LTB4, ED50 = 0.65 mg/kg, 6 h pretreatment) and in the hyperreactive rat model of antigen-induced dyspnea (50% inhibition at 2 and 4 h pretreatment; 0.5 mg/kg po). In addition, 14d shows excellent functional activity against antigen-induced bronchoconstriction in the conscious squirrel monkey [89% inhibition of the increase in RL and 68% inhibition in the decrease in Cdyn (0.1 mg/kg, n = 3)] and in the conscious sheep models of asthma (iv infusion at 2.5 micrograms/kg/min). Acid 14d is highly selective as an inhibitor of 5-LO activity when compared to the inhibition of human 15-LO, porcine 12-LO and ram seminal vesicle cyclooxygenase (IC50 > 5 microM) or competition in a FLAP binding assay (IC50 > 10 microM). Resolution of 14d affords 14g, the most potent diastereomer, which inhibits the 5-HPETE production of human 5-LO and LTB4 biosynthesis of human PMN leukocytes and human whole blood with IC50s of 8 nM, 4 nM, and 1 microM respectively. The in vitro and in vivo profile of 14d is comparable to that of MK-0591, which has showed biochemical efficacy in inhibiting ex vivo LTB4 biosynthesis and urinary LTE4 excretion in clinical trials.


Asunto(s)
Indoles/síntesis química , Inhibidores de la Lipooxigenasa , Piridinas/síntesis química , Animales , Broncoconstricción/efectos de los fármacos , Calcimicina/farmacología , Cromatografía Líquida de Alta Presión , Humanos , Indoles/química , Indoles/farmacología , Leucotrieno B4/biosíntesis , Leucotrienos/biosíntesis , Inhibidores de la Lipooxigenasa/farmacología , Masculino , Estructura Molecular , Piridinas/química , Piridinas/farmacología , Ratas , Ratas Sprague-Dawley , Saimiri , Ovinos , Estereoisomerismo , Relación Estructura-Actividad , Porcinos
9.
Environ Pollut ; 80(3): 231-8, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-15091842

RESUMEN

The purpose of this study was to examine the effects of diazinon and acephate applications to ornamental trees on the breeding behaviour and productivity of the American robin and to measure the effect of repeated chlorpyrifos spraying on robin productivity. No cases of adult or juvenile mortality were recorded, and nestling production was not affected. Plasma cholinesterase (ChE) activity in females exposed to diazinon or acephate was significantly lower than that in controls. However, there were no pronounced changes in parental care. The absence of a significant impact on behaviour despite the marked change in plasma ChE levels may have been due to one of several factors, i.e. (1) the insecticide had not reached the brain 18 to 24 h after spraying, and (2) exposure was insufficient to produce behavioural changes. The use of diazinon and acephate on ornamental trees should not be harmful to robins. There was a negative correlation between nest productivity and the number of lawns surrounding the nest treated with chlorpyrifos once or more in the preceding 2 years. The decline in earthworm numbers and their reduced biomass due to repeated chlorpyrifos use may account for the lower productivity recorded during the nesting season.

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