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1.
Int J Immunopathol Pharmacol ; 27(1): 53-67, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24674679

RESUMO

Class IA phosphatidyl inositol-3 kinases (PI3-K) are important targets in cancer therapy and are essential to immune responses, particularly through costimulation by CD28 and ICOS. Thus, small PI3-K inhibitors are likely candidates to immune intervention. PIK-75 is an efficient inhibitor of the PI3-K p110alpha catalytic subunits that suppresses tumor growth, and its effects on immune and autoimmune responses should be studied. Here, we describe the effect of PIK-75 on different immune parameters in vitro and in vivo. PIK-75 at concentrations commonly used in vitro (≥0.1 μM) inhibited T and B cell activation by Concanavalin A and LPS, respectively, and survival of non-stimulated spleen cells. In naive CD4+ T lymphocytes, PIK-75 induced apoptosis of resting or activated cells that was prevented by caspase inhibitors. At low nanomolar concentrations (≤10 nM), PIK-75 inhibited naive CD4+ T cell proliferation, and IL-2 and IFN-gamma production induced by anti-CD3 plus anti-CD28. In activated CD4+ T blasts costimulated by ICOS, PIK-75 (less than 10 nM) inhibited IFN-gamma, IL-17A, or IL-21 secretion. Furthermore, PIK-75 (20 mg/kg p.o.) suppressed clinical symptoms in ongoing experimental autoimmune encephalomyelitis (EAE) and inhibited MOG-specific responses in vitro. Thus, PIK-75 is an efficient suppressor of EAE, modulating lymphocyte function and survival.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Encefalomielite Autoimune Experimental/tratamento farmacológico , Hidrazonas/uso terapêutico , Ativação Linfocitária/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase , Sulfonamidas/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/enzimologia , Linfócitos T CD4-Positivos/patologia , Células Cultivadas , Citocinas/análise , Relação Dose-Resposta a Droga , Encefalomielite Autoimune Experimental/enzimologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Hidrazonas/administração & dosagem , Hidrazonas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacologia
2.
J Clin Microbiol ; 47(4): 1012-20, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19225097

RESUMO

Temporal trends of serotypes from invasive pneumococcal disease (IPD) in Spain from 1979 to September 2007 under antibiotic and vaccine pressure were analyzed. A significant trend in pneumococcal conjugate 7-valent vaccine (PCV7) serotypes (except serotype 4) was found, whereby the prevalence increased from the early 1980s and decreased in the 2000s for all but serotype 23F, which began decreasing in the late 1980s. Among the major non-PCV7 serotypes, a significant decrease was observed for serotypes 1, 5, and 7F in the 1980s. From the late 1990s, serotypes 1, 5, 6A, 7F, and 19A increased significantly, while serotypes 3 and 8 showed similar but nonsignificant trends over time. The incidence of IPD cases was 10.7/100,000 for the period 1996 to 2006, with reporting coverage ranging from 18% to 43%. A significant decrease in IPD incidence due to PCV7 serotypes was observed, while the incidence of non-PCV7 serotypes increased, with the consequence that there was no clear pattern in the overall incidence of IPD. Penicillin nonsusceptibility was correlated with the proportion of PCV7 serotypes. Erythromycin nonsusceptibility increased in association with long-half-life macrolide consumption and then decreased in 2004 to 2007. The increase in PCV7 serotypes and antibiotic nonsusceptibility related to antibiotic consumption in the 1980s and 1990s was reversed in the 2000s, probably as a result of PCV7 immunization. The decrease in IPD incidence due to PCV7 serotypes was mirrored by an increase in that of non-PCV7 serotypes. The impact of various preventive/therapeutic strategies on pneumococcal evolution is serotype dependent, and the dynamics remain unpredictable.


Assuntos
Técnicas de Tipagem Bacteriana , Farmacorresistência Bacteriana , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/efeitos dos fármacos , Adolescente , Antibacterianos/farmacologia , Criança , Pré-Escolar , Uso de Medicamentos/estatística & dados numéricos , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Incidência , Lactente , Recém-Nascido , Testes de Sensibilidade Microbiana , Vacinas Pneumocócicas/imunologia , Prevalência , Sorotipagem , Espanha , Streptococcus pneumoniae/isolamento & purificação
3.
J Antimicrob Chemother ; 62(6): 1430-3, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18819966

RESUMO

OBJECTIVES: The aim of the study was to analyse the evolution of antibiotic non-susceptibility in Spanish invasive Streptococcus pneumoniae after licensure of respiratory-quinolones for adults and 7-valent pneumococcal conjugate vaccine (PCV-7) for immunization of children. METHODS: All invasive pneumococci received in the Reference Laboratory (January 2000-August 2007; n = 12 957 isolates) were serotyped, and susceptibility to penicillin/erythromycin/levofloxacin was determined. Antibiotic consumption and PCV-7 doses/year were provided by IMS and the manufacturer, respectively. RESULTS: In 2000-07, PCV-7 distribution (doses/1000 inhabitants

Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Infecções Pneumocócicas/microbiologia , Infecções Pneumocócicas/transmissão , Vacinas Pneumocócicas/imunologia , Quinolonas/uso terapêutico , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/imunologia , Adulto , Antibacterianos/farmacologia , Criança , Eritromicina/farmacologia , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Testes de Sensibilidade Microbiana , Penicilinas/farmacologia , Quinolonas/farmacologia , Sorotipagem , Espanha , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/isolamento & purificação
4.
Br J Pharmacol ; 154(3): 698-708, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18414382

RESUMO

BACKGROUND AND PURPOSE: Dendritic cells (DCs) are dedicated antigen-presenting cells able to initiate specific immune responses and their maturation is critical for the induction of antigen-specific T-lymphocyte responses. Here, we have investigated the effects of Inmunoferon-active principle (AM3), the active agent of a commercial immunomodulatory drug, on human monocyte-derived DCs (MDDCs). EXPERIMENTAL APPROACH: MDDCs derived from healthy and hepatitis C virus (HCV)-infected patients were stimulated with AM3. We analysed the expression of cell surface proteins by flow cytometry, that of cytokine production by ELISA, and the expression of chemokines and chemokine receptors by RNase protection assays. T-lymphocyte proliferation was assessed in mixed lymphocyte reactions, protein expression by western blot and luciferase-based reporter methods, and Toll-like receptor (TLR)-blocking antibodies were employed to analyse TLR activity. KEY RESULTS: In MDDCs, AM3 induced or enhanced expression of CD54, CD83, CD86, HLA-DR, chemokines and chemokine receptors, interleukin (IL)-12p70 and IL-10. Furthermore, AM3 stimulated MDDCs to increase proliferation of allogenic T cells. AM3 triggered nuclear translocation of NF-kappaB and phosphorylation of p38 mitogen-activated protein kinase. AM3 promoted NF-kappaB activation in a TLR-4-dependent manner, and blocking TLR-4 activity attenuated the enhanced expression of CD80, CD83 and CD86 induced by AM3. AM3 enhanced the expression of maturation-associated markers in MDDCs from HCV-infected patients and increased the proliferation of T lymphocytes induced by these MDDCs. CONCLUSIONS AND IMPLICATIONS: These results underline the effects of AM3 in promoting maturation of MDDCs and suggest that AM3 might be useful in regulating immune responses in pathophysiological situations requiring DC maturation.


Assuntos
Adjuvantes Imunológicos/farmacologia , Fosfatos de Cálcio/farmacologia , Células Dendríticas/efeitos dos fármacos , Glicopeptídeos/farmacologia , Idoso , Western Blotting , Proliferação de Células/efeitos dos fármacos , Quimiocinas/efeitos dos fármacos , Quimiocinas/metabolismo , Células Dendríticas/metabolismo , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatite C/metabolismo , Humanos , Pessoa de Meia-Idade , Receptores de Quimiocinas/efeitos dos fármacos , Receptores de Quimiocinas/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Receptor 4 Toll-Like/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo
5.
Clin Transl Oncol ; 9(2): 77-82, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17329218

RESUMO

Dendritic cells are bone marrow-derived professional antigen-presenting cells that exert critical functions in innate and adaptive immune responses. Depending on their functional maturation status, dendritic cells trigger primary immune responses or promote immunological tolerance. This functional ambivalence has taken dendritic cells into the focus of attention of immunotherapy protocols for both vaccination and tolerance induction. The capacity of dendritic cells to generate anti-tumour immune responses has already been demonstrated, and numerous clinical trials are currently in progress to assess their therapeutic potential. In the present review we will briefly outline the types and effector functions of dendritic cells in the human system, and summarise the present state of anti-tumour immunotherapy protocols, emphasising the most relevant parameters currently evaluated in preclinical and clinical assays.


Assuntos
Células Dendríticas/imunologia , Imunoterapia Adotiva , Neoplasias/imunologia , Neoplasias/terapia , Humanos , Imunoterapia Adotiva/métodos
7.
Rev Neurol ; 43(9): 531-4, 2006.
Artigo em Espanhol | MEDLINE | ID: mdl-17072808

RESUMO

INTRODUCTION: Oedema of the papilla, or papilloedema, is usually due to intracranial hypertension, but can sometimes be the initial symptom of systemic diseases like Guillain-Barre syndrome, neurosarcoidosis, Leber's disease, Lyme disease or POEMS syndrome, among others. We report on a case that occurred at the Hospital General Universitario in Alicante, in which papilloedema was the initial symptom of POEMS syndrome. CASE REPORT: A 36-year-old female, with no relevant past history, who visited after suffering a left-side frontal oppressive headache for five days; onset was sudden, there was no concomitant nausea or vomiting, it did not get worse when Valsalva manoeuvres were performed and there were no other accompanying symptoms. The examination revealed nasal blurring in the visual field of the right eye and papilloedema in the left eye, hyperpigmentation of the skin on the face and upper chest area that respected creases in the skin, painful distal tactile hypaesthesia in the lower limbs and bilateral areflexia of Achilles' tendons and patellar hyperreflexia. After conducting a number of different complementary tests intracranial space-occupying lesions and intracranial hypotension were both ruled out and the patient was diagnosed with mixed-type sensory-motor chronic polyneuropathy in the upper limbs, and in the lower extremities with predominantly distal involvement, bilateral oedema of the papilla and skin photosensitivity. Two years later the patient had hepatomegaly, subclinical hypothyroidism and sclerodermiform alterations of the skin, which suggested a probable diagnosis of POEMS syndrome that was later confirmed by the presence of monoclonal component in blood and urine. CONCLUSIONS: Papilloedema is rarely seen as the initial symptom of POEMS syndrome, but it must be included in the differential diagnosis of this pathology due to the diagnostic and therapeutic implications it entails.


Assuntos
Síndrome POEMS/complicações , Síndrome POEMS/diagnóstico , Papiledema/etiologia , Adulto , Feminino , Humanos
8.
Biochem Pharmacol ; 106: 56-69, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26883061

RESUMO

Class IA phosphoinositide 3-kinases (PI3Ks) are essential to function of normal and tumor cells, and to modulate immune responses. T lymphocytes express high levels of p110α and p110δ class IA PI3K. Whereas the functioning of PI3K p110δ in immune and autoimmune reactions is well established, the role of p110α is less well understood. Here, a novel dual p110α/δ inhibitor (ETP-46321) and highly specific p110α (A66) or p110δ (IC87114) inhibitors have been compared concerning T cell activation in vitro, as well as the effect on responses to protein antigen and collagen-induced arthritis in vivo. In vitro activation of naive CD4(+) T lymphocytes by anti-CD3 and anti-CD28 was inhibited more effectively by the p110δ inhibitor than by the p110α inhibitor as measured by cytokine secretion (IL-2, IL-10, and IFN-γ), T-bet expression and NFAT activation. In activated CD4(+) T cells re-stimulated through CD3 and ICOS, IC87114 inhibited Akt and Erk activation, and the secretion of IL-2, IL-4, IL-17A, and IFN-γ better than A66. The p110α/δ inhibitor ETP-46321, or p110α plus p110δ inhibitors also inhibited IL-21 secretion by differentiated CD4(+) T follicular (Tfh) or IL-17-producing (Th17) helper cells. In vivo, therapeutic administration of ETP-46321 significantly inhibited responses to protein antigen as well as collagen-induced arthritis, as measured by antigen-specific antibody responses, secretion of IL-10, IL-17A or IFN-γ, or clinical symptoms. Hence, p110α as well as p110δ Class IA PI3Ks are important to immune regulation; inhibition of both subunits may be an effective therapeutic approach in inflammatory autoimmune diseases like rheumatoid arthritis.


Assuntos
Artrite Experimental/tratamento farmacológico , Linfócitos T CD4-Positivos/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Subunidades Proteicas/antagonistas & inibidores , Pirazinas/farmacologia , Animais , Anticorpos/farmacologia , Artrite Experimental/enzimologia , Artrite Experimental/imunologia , Artrite Experimental/patologia , Antígenos CD28/genética , Antígenos CD28/imunologia , Complexo CD3/genética , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/enzimologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Classe Ia de Fosfatidilinositol 3-Quinase/genética , Classe Ia de Fosfatidilinositol 3-Quinase/imunologia , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/imunologia , Expressão Gênica , Interferon gama/genética , Interferon gama/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-2/genética , Interleucina-2/imunologia , Linfonodos/efeitos dos fármacos , Linfonodos/enzimologia , Linfonodos/imunologia , Linfonodos/patologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/imunologia , Subunidades Proteicas/genética , Subunidades Proteicas/imunologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/imunologia , Proteínas com Domínio T/genética , Proteínas com Domínio T/imunologia
9.
Biochim Biophys Acta ; 1548(1): 1-22, 2001 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-11451433

RESUMO

Tyrosinase can act on monophenols because of the mixture of met- (E(m)) and oxy-tyrosinase (E(ox)) which exists in the native form of the enzyme. The latter form is active on monophenols, while the former is not. However, the kinetics are complicated because monophenols can bind to both enzyme forms. This situation becomes even more complex since the products of the enzymatic reaction, the o-quinones, are unstable and continue evolving to generate o-diphenols in the medium. In the case of substrates such as L-tyrosine, tyrosinase generates very unstable o-quinones, in which a process of cyclation and subsequent oxidation-reduction generates o-diphenol through non-enzymatic reactions. However, the release of o-diphenol through the action of the enzyme on the monophenol contributes to the concentration of o-diphenol in the first pseudo-steady-state [D(0)](ss). Hence, the system reaches an initial pseudo-steady state when t-->0 and undergoes a transition phase (lag period) until a final steady state is reached when the concentration of o-diphenol in the medium reaches the concentration of the final steady state [D(f)](ss). These results can be explained by taking into account the kinetic and structural mechanism of the enzyme. In this, tyrosinase hydroxylates the monophenols to o-diphenols, generating an intermediate, E(m)D, which may oxidise the o-diphenol or release it directly to the medium. We surmise that the intermediate generated during the action of E(ox) on monophenols, E(m)D, has axial and equatorial bonds between the o-diphenol and copper atoms of the active site. Since the orbitals are not coplanar, the concerted oxidation-reduction reaction cannot occur. Instead, a bond, probably that of C-4, is broken to achieve coplanarity, producing a more labile intermediate that will then release the o-diphenol to the medium or reunite it diaxially, involving oxidation to o-quinone. The non-enzymatic evolution of the o-quinone would generate the o-diphenol ([D(f)](ss)) necessary for the final steady state to be reached after the lag period.


Assuntos
Agaricales/enzimologia , Monofenol Mono-Oxigenase/química , Fenóis/química , Quinonas/química , Catecol Oxidase/química , Relação Dose-Resposta a Droga , Cinética , Levodopa/química , Modelos Químicos , Modelos Teóricos , Monofenol Mono-Oxigenase/farmacologia , Espectrofotometria , Tirosina/química
10.
Biochim Biophys Acta ; 1548(2): 238-56, 2001 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-11513969

RESUMO

Using gas chromatography-mass spectrometry, the direct enzymatic release of o-diphenol (4-tert-butylcatechol) during the action of tyrosinase on a monophenol (4-tert-butylphenol) has been demonstrated for the first time in the literature. The findings confirm the previously proposed mechanism to explain the action of tyrosinase on monophenols (J.N. Rodríguez-López, J. Tudela, R. Varón, F. García-Carmona, F. García-Cánovas, J. Biol. Chem. 267 (1992)). Oxytyrosinase, the oxidized form of the enzyme with a peroxide group, is the only form capable of catalysing the transformation of monophenols into diphenols, giving rise to an enzyme-substrate complex in the process. The o-diphenol formed is then released from the enzyme-substrate complex or oxidized to the corresponding o-quinone. In order to detect the enzymatic release of o-diphenol, the non-enzymatic evolution of the o-quinone to generate o-diphenol by weak nucleophilic attack reactions and subsequent oxidation-reduction was blocked by the nucleophilic attack of an excess of cysteine. Furthermore, the addition of catalytic quantities of an auxiliary o-diphenol (e.g. catechol) considerably increases the accumulation of 4-tert-butylcatechol. The enzyme acting on 4-tert-butylphenol generates the enzyme-4-tert-butylcatechol complex and 4-tert-butylcatechol is then released (with k(-2)) generating mettyrosinase. The auxiliary o-diphenol added (catechol) and the 4-tert-butylcatechol generated by the enzyme then enter into competition. When [catechol] >> [4-tert-butylcatechol], the enzyme preferentially binds with the catechol to close the catalytic cycle, while 4-tert-butylcatechol is accumulated in the medium. In conclusion, we demonstrate that the enzyme produces 4-tert-butylcatechol from 4-tert-butylphenol, the concentration of which increases considerably in the presence of an auxiliary o-diphenol such as catechol.


Assuntos
Catecóis/química , Monofenol Mono-Oxigenase/química , Fenóis/química , Agaricales , Benzoquinonas/química , Catecóis/farmacologia , Cisteína/química , Cisteína/farmacologia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cinética , Melanossomas/metabolismo , Modelos Químicos , Modelos Teóricos , Monofenol Mono-Oxigenase/metabolismo , Oxirredução
11.
Rev Neurol ; 41(11): 643-8, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16317632

RESUMO

INTRODUCTION: Neuropathic pain (NP) is defined as pain that begins with or is caused by a primary injury or by a dysfunction in the nervous system. AIMS: Our aim was to evaluate how often patients visit Neurology as outpatients with NP as the main reason for referral. PATIENTS AND METHODS: A descriptive, cross sectional study was carried out on the use of the health care services; patients attended for the first time in a Neurology Screening visit were included consecutively. The variables studied were the following: the number of first visits and the total number of patients attended per visiting session, rate of patients with NP per visiting day, the topography and probable causation of the NP, and the rate of patients referred to the monographic NP clinic; the different quantitative variables are expressed in terms of their mean and standard deviation (SD), whereas the qualitative variables are given as their absolute value and the percentage. A total of 1,972 patients were attended, of whom 1,422 (72.1%) were first visits, with an average of 17.5 (SD: 2.5) new patients per visiting session. RESULTS: In all 113 patients clinically diagnosed with NP were identified, which represents a rate of 7.95% of the first visits. CONCLUSIONS: NP may be among the most frequent causes of the demand for neurological ambulatory care. The most common causes of NP were found to be trigeminal neuralgia, post-herpes neuralgia and diabetic polyneuropathy.


Assuntos
Instituições de Assistência Ambulatorial , Departamentos Hospitalares , Neurologia , Dor/epidemiologia , Estudos Transversais , Necessidades e Demandas de Serviços de Saúde , Humanos , Dor/diagnóstico , Dor/etiologia , Manejo da Dor , Encaminhamento e Consulta
12.
Int J Biochem Cell Biol ; 36(2): 235-46, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14643889

RESUMO

The kinetic behaviour of tyrosinase is very complex because the enzymatic oxidation of monophenol and o-diphenol to o-quinones occurs simultaneously with the coupled non-enzymatic reactions of the latter. Both reaction types are included in the kinetic mechanism proposed for tyrosinase (Mechanism I [J. Biol. Chem. 267 (1992) 3801-3810]). We previously confirmed the validity of the rate equations by the oxidation of numerous monophenols and o-diphenols catalysed by tyrosinase from different fruits and vegetables. Other authors have proposed a simplified reaction mechanism for tyrosinase (Mechanism II [Theor. Biol. 203 (2000) 1-12]), although without deducing the rate equations. In this paper, we report new experimental work that provides the lag period value, the steady-state rate, o-diphenol concentration released to the reaction medium. The contrast between these experimental data and the respective numerical simulations of both mechanisms demonstrates the feasibility of Mechanism I. The need for the steps omitted from Mechanism II to interpret the experimental data for tyrosinase, based on the rate equations previously deduced for Mechanism I is explained.


Assuntos
Agaricales/enzimologia , Bioquímica/métodos , Monofenol Mono-Oxigenase/química , Oxigênio/metabolismo , Fenol/química , Cromatografia Gasosa , Relação Dose-Resposta a Droga , Eletroquímica , Cinética , Espectrometria de Massas , Modelos Químicos , Monofenol Mono-Oxigenase/metabolismo , Espectrofotometria
13.
Biophys Chem ; 84(1): 65-76, 2000 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-10723545

RESUMO

Tyrosinase hydroxylates 3-hydroxyanisole in the 4-position. The reaction product accumulates in the reaction medium with a lag time (tau) which diminishes with increasing concentrations of enzyme and lengthens with increasing concentrations of substrate, thus fulfilling all the predictions of the mechanism proposed by us for 4-hydroxyphenols. The kinetic constants obtained, kcatM = (46.87 +/- 2.06) s-1 and KmM = (5.40 +/- 0.60) mM, are different from those obtained with 4-hydroxyanisole, kcatM = (184.20 +/- 6.1) s-1 and KmM = (0.08 +/- 0.004) mM. The catalytic efficiency, kcatM/KmM is, therefore, 265.3 times greater with 4-hydroxyanisole. The possible rate-determining steps for the reaction mechanism of tyrosinase on 3- and 4-hydroxyanisole, based on the NMR spectra of both monophenols, are discussed. These possible rate-determining steps are the nucleophilic attack of hydroxyl's oxygen on the copper and the electrophilic attack of the peroxide on the aromatic ring. Both steps may be of similar magnitude, i.e. take place in the same time scale.


Assuntos
Anisóis/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Agaricales/enzimologia , Benzotiazóis , Catálise , Hidrazonas , Hidroxilação , Isomerismo , Cinética , Ressonância Magnética Nuclear Biomolecular , Oxirredução , Tiazóis
14.
J Agric Food Chem ; 47(8): 3028-35, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10552603

RESUMO

Browning reactions in fruits and vegetables are a serious problem for the food industry. In mushrooms, the principal enzyme responsible for the browning reaction is polyphenoloxidase (PPO). A microwave applicator has been designed and used for studying mushroom PPO inactivation. The effects of microwaves and conventional heating on the kinetics of the monophenolase and diphenolase activities of PPO were studied. Conventional and microwave treatments produce different enzyme intermediates with different stability and kinetic properties. We describe how considerable time can be saved during microwave inactivation of the enzyme compared with the time needed when conventional hot-water treatment is used, resulting in greater profitability and enhanced quality. The short exposure time required for samples irradiated with microwaves is very important for maintaining the quality of mushrooms. The fast microwave treatment used resulted in an increase in antioxidant content and a considerable decrease in browning.


Assuntos
Agaricales/enzimologia , Agaricus/enzimologia , Catecol Oxidase/química , Micro-Ondas , Catecol Oxidase/antagonistas & inibidores , Catecol Oxidase/efeitos da radiação , Culinária , Temperatura Alta , Cinética , Reação de Maillard , Termodinâmica
15.
J Agric Food Chem ; 47(11): 4506-11, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10552842

RESUMO

Browning reactions in fruits and vegetables are a serious problem for the food industry. In mushrooms, the principal enzyme responsible for the browning reaction is polyphenoloxidase (PPO). Microwaves have recently been introduced as an alternative for the industrial blanching of mushrooms. However, the direct application of microwave energy to entire mushrooms is limited by the important temperature gradients generated within the samples during heating, which can produce internal water vaporization and associated damage to the mushrooms texture. A microwave applicator has been developed, whereby irradiation conditions can be regulated and the heating process monitored. Whole edible mushrooms (Agaricus bisporus) were blanched by conventional, microwave, and combined heating methods to optimize the rate of PPO inactivation. A combined microwave and hot-water bath treatment has achieved complete PPO inactivation in a short time. Both the loss of antioxidant content and the increase of browning were minor in the samples treated with this combined method when compared to the control. This reduction in processing time also decreased mushroom weight loss and shrinkage.


Assuntos
Agaricales/enzimologia , Catecol Oxidase/metabolismo , Manipulação de Alimentos/métodos , Temperatura Alta , Micro-Ondas
16.
Arch Mal Coeur Vaiss ; 77(4): 386-96, 1984 Apr.
Artigo em Francês | MEDLINE | ID: mdl-6144295

RESUMO

Coronary arteries like other branches of the aorta may be involved in Takayasu's disease. This complication is not rare (7% of cases) but appears to be relatively unappreciated. Three new cases are reported of main coronary artery disease, two of which were treated by coronary bypass surgery. A review of the literature of 1 130 cases of Takayasu's disease revealed 86 cases with coronary involvement, 33 of which were confirmed anatomically and 15 by coronary arteriography. The clinical manifestations, angina and/or myocardial infarction, were present in 5% and 3% respectively, of patients with Takayasu's disease. They may be the first sign of the disease and, in some cases, the only symptomatic arterial localisation. The coronary lesions are either ostial, a direct complication of the aortic disease, or on a main vessel, usually proximal. Histological studies show typical changes of stenosing inflammatory panarteritis involving mainly the media and adventitia. Thrombosis and secondary atheromatous plaques may be observed. Aneurysms are rare. Apart from cases with typical ostial lesions, the coronary angiographic appearances are not specific, but some features are suggestive of the diagnosis; the occurrence in young women; the presence of associated peripheral arterial lesions, their localisation and grouping; their radiological and/or histological characteristics. The spontaneous prognosis of these proximal lesions is usually poor and justifies surgical revascularisation by coronary bypass. Six patients, including two in this series, have been treated surgically. The associated aortic lesions may pose special technical problems which we discussed. The relatively high incidence of coronary involvement in Takayasu's disease and its often unexpected revelation by myocardial infarction or sudden death, suggest that coronary arteriography should be undertaken more often during investigation of the arterial lesions of these patients. Takayasu's disease should figure prominently amongst the causes of coronary artery disease in young women.


Assuntos
Síndromes do Arco Aórtico/complicações , Doença das Coronárias/etiologia , Vasos Coronários/patologia , Arterite de Takayasu/complicações , Adolescente , Adulto , Criança , Angiografia Coronária , Ponte de Artéria Coronária , Doença das Coronárias/diagnóstico , Doença das Coronárias/cirurgia , Feminino , Seguimentos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Arterite de Takayasu/cirurgia
17.
Rev Neurol ; 38(12): 1152-5, 2004.
Artigo em Espanhol | MEDLINE | ID: mdl-15229830

RESUMO

INTRODUCTION: The presence of quick onset binocular diplopy makes it essential to carry out a comprehensive differential diagnosis. The most frequent causes in adults include vascular, post-traumatic, tumorous and myopathic pathologies. Yet, to perform a differential diagnosis we also have to take into account less common aetiologies such as demyelinating disease, carotid-cavernous fistulas and Tolosa Hunt syndrome, among others. We report the case of a patient who was admitted to our hospital because she presented an acute onset diplopy secondary to a spontaneous haematoma of the left rectus inferior. CASE REPORT: We describe the case of a 54-year-old female with a history of hypercholesterolemia, who was a smoker and allergic to iodine contrasts and who visited because of an acute onset diplopy accompanied by instability and pain in the left eye. The neurological examination revealed paresis of the extraocular muscles dependent on the left oculomotor nerve with left palpebral ptosis, paresis of the rectus inferior, with no involvement of the pupils. Other results of the exploration were within normal limits. A computerised axial tomography scan of the head showed a haemorrhage in the rectus inferior. Magnetic resonance images of the head revealed an increase in the volume of the left-side rectus inferior with signs of bleeding, and the rest of the complementary explorations were normal. The patient progressed favourably and the diplopy gradually disappeared. CONCLUSIONS: Spontaneous bleeding of the extraocular muscles, although infrequent, must be taken into account in the differential diagnosis of painful ophthalmoplegia with diplopy in patients with no underlying pathology, especially in the absence of other neurological disorders.


Assuntos
Diplopia/etiologia , Hematoma/complicações , Músculos Oculomotores/patologia , Diagnóstico Diferencial , Diplopia/patologia , Feminino , Hematoma/diagnóstico , Hematoma/patologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
18.
Eur Ann Otorhinolaryngol Head Neck Dis ; 130(3): 149-51, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23395284

RESUMO

INTRODUCTION: Tongue metastasis of renal cell carcinoma (RCC) is rare. Treatment is hindered by the proximity of anatomic structures involved in swallowing, speech and mastication. It is, moreover, radioresistant. CASE REPORT: We report a case of inaugural isolated tongue metastasis, where biopsy redirected diagnosis to RCC. To avoid potentially mutilating excision in a metastatic disease of poor prognosis, treatment was local, consisting in interstitial brachytherapy, enabling a high dose (65Gy) to be delivered. Despite initially complete response, recurrence at 10.5months required salvage surgery. DISCUSSION AND CONCLUSION: Brachytherapy allowed a higher dose to be delivered than with external beam radiation therapy, previously reported for similar cases. This dose, which can usually be expected to ensure local control in 90% of squamous cell carcinomas of the tongue, obtained 10months' response, insufficient to avoid salvage surgery.


Assuntos
Braquiterapia , Carcinoma de Células Renais/radioterapia , Carcinoma de Células Renais/secundário , Neoplasias Renais/patologia , Neoplasias Renais/radioterapia , Recidiva Local de Neoplasia , Neoplasias da Língua/radioterapia , Neoplasias da Língua/secundário , Idoso , Braquiterapia/métodos , Carcinoma de Células Renais/cirurgia , Evolução Fatal , Seguimentos , Glossectomia , Humanos , Neoplasias Renais/cirurgia , Masculino , Invasividade Neoplásica , Recidiva Local de Neoplasia/cirurgia , Nefrectomia , Dosagem Radioterapêutica , Terapia de Salvação , Neoplasias da Língua/cirurgia
20.
Rev Neurol ; 52(2): 90-4, 2011 Jan 16.
Artigo em Espanhol | MEDLINE | ID: mdl-21271548

RESUMO

INTRODUCTION: Fibrous dysplasia is a bone disease that is usually accompanied by asymptomatic lesions but which may sometimes display neurological manifestations due to the involvement of the craniofacial bones. CASE REPORT: A 25-year-old female, with a history of migraines, who visited at the age of 18 due to pain in the right retro-ocular and maxillary region, although with characteristics that were unlike those of her usual migraines, and which was associated with ipsilateral ophthalmoparesis. The condition had a self-limiting course and responded well to corticoids, although it was recurring. Examination revealed intense pain on palpation of the right-hand maxillary sinus and incomplete paralysis of the ipsilateral oculomotor nerve with palpebral ptosis. Results of complementary studies were normal, except for magnetic resonance imaging of the head and computerised axial tomography of the face, which revealed an expansive lesion with involvement of the right superior maxillary sinus and the greater wing of the sphenoid bone, with probable compromise of the superior orbital fissure, consistent with the diagnosis of fibrous dysplasia, which was confirmed by means of a pathology study. CONCLUSIONS: Fibrous dysplasia is a benign bone disorder, of unknown causation, in which normal bone tissue is replaced by amorphous conjunctive tissue. There is sometimes craniofacial involvement and a hypertrophic bone mass is formed which can fill the paranasal sinuses and the orbit, resulting in exophthalmus and visual disorders. To date the scientific literature does not include any reports of this disease manifesting as bouts of recurrent painful ophthalmoparesis which responds to corticoids, as happened in the case of our patient.


Assuntos
Displasia Fibrosa Poliostótica/complicações , Displasia Fibrosa Poliostótica/patologia , Seio Maxilar/patologia , Órbita/patologia , Corticosteroides/uso terapêutico , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Seio Maxilar/diagnóstico por imagem , Órbita/diagnóstico por imagem , Osso Esfenoide/diagnóstico por imagem , Osso Esfenoide/patologia , Síndrome de Tolosa-Hunt/tratamento farmacológico , Síndrome de Tolosa-Hunt/etiologia , Tomografia Computadorizada por Raios X
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