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1.
Artículo en Inglés | MEDLINE | ID: mdl-38221868

RESUMEN

BACKGROUND: Allergic disease affects up to 40% of the global adult population, a proportion that is increasing with environmental changes related to global warming. METHODS: We undertook a systematic review of the literature to identify and evaluate the current evidence of the impact of climate change-related environmental factors on the allergen production and the epidemiology and severity of allergic pathologies. PECO criteria were established and guided the literature searches of the PubMed and Cochrane databases (Jan 1, 2016 to Dec 31, 2021). Study outcomes were categorized and grouped to facilitate data synthesis. Outcomes were classified as significant (statistical significance <0.05), non-significant (p>0.05) or undetermined (p value not reported). Study quality was assessed using MMAT analysis. RESULTS: Of 195 studies, 40 were considered relevant and 9 of them provided data to be included in the data quantitative synthesis. Environmental factors, including the presence of pollutants, temperature, and drought, influenced the type, volume, and timing of exposure to local aeroallergens. The most relevant environmental factor was the presence of environmental pollutants, of which tropospheric ozone was the most frequently associated to changes in allergen production, prevalence, and severity of allergic disease. Also, several publications demonstrated the impact of environmental factors on the healthcare burden. CONCLUSIONS: Climate-change related environmental factors increased allergic disease in terms of prevalence, severity, and healthcare burden due to alterations in allergen exposure (volume and type) with the presence of pollutants such as ozone being the most commonly reported driver of such increase.

2.
Br J Cancer ; 109(10): 2654-64, 2013 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-24136149

RESUMEN

BACKGROUND: The DNA-repair gene DNA-dependent kinase catalytic subunit (DNA-PKcs) favours or inhibits carcinogenesis, depending on the cancer type. Its role in human hepatocellular carcinoma (HCC) is unknown. METHODS: DNA-dependent protein kinase catalytic subunit, H2A histone family member X (H2AFX) and heat shock transcription factor-1 (HSF1) levels were assessed by immunohistochemistry and/or immunoblotting and qRT-PCR in a collection of human HCC. Rates of proliferation, apoptosis, microvessel density and genomic instability were also determined. Heat shock factor-1 cDNA or DNA-PKcs-specific siRNA were used to explore the role of both genes in HCC. Activator protein 1 (AP-1) binding to DNA-PKcs promoter was evaluated by chromatin immunoprecipitation. Kaplan-Meier curves and multivariate Cox model were used to study the impact on clinical outcome. RESULTS: Total and phosphorylated DNA-PKcs and H2AFX were upregulated in HCC. Activated DNA-PKcs positively correlated with HCC proliferation, genomic instability and microvessel density, and negatively with apoptosis and patient's survival. Proliferation decline and massive apoptosis followed DNA-PKcs silencing in HCC cell lines. Total and phosphorylated HSF1 protein, mRNA and activity were upregulated in HCC. Mechanistically, we demonstrated that HSF1 induces DNA-PKcs upregulation through the activation of the MAPK/JNK/AP-1 axis. CONCLUSION: DNA-dependent protein kinase catalytic subunit transduces HSF1 effects in HCC cells, and might represent a novel target and prognostic factor in human HCC.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinogénesis/genética , Carcinoma Hepatocelular/patología , Proteína Quinasa Activada por ADN/genética , Neoplasias Hepáticas/patología , Proteínas Nucleares/genética , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular/genética , Proteínas de Unión al ADN/fisiología , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Factores de Transcripción del Choque Térmico , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Valor Predictivo de las Pruebas , Pronóstico , Factores de Transcripción/fisiología
3.
Rheumatol Int ; 32(2): 335-41, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21085966

RESUMEN

In our previous study, we observed that the presence of autoimmune thyroid disease worsens fibromyalgia (FM) symptoms. The aims of this study are to evaluate whether there is a predisposition for the development of FM in patients with Hashimoto's thyroiditis (HT) with or without subclinical hypothyroidism (SCH) and in patients with SCH alone and what is the weight of antithyroid antibody positivity and SCH on FM comorbidity. Fifty-two patients, 39 affected by HT with or without SCH and 13 by SCH, were matched with 37 patients affected by FM and 25 healthy subjects. Blood samples were collected from all study subjects for the determination of serum TSH, free triiodothyronine, free thyroxine, antithyroperoxidase antibody (TPOAb), antithyroglobulin antibody (TgAb) and non-organ-specific autoantibodies. Clinical assessment of patients and controls included the "Fibromyalgia Impact Questionnaire" (FIQ), while pain severity was evaluated using a visual analogue scale (VAS). Patients and controls were also characterized by the presence of diffuse pain, fatigue, paresthesiae, muscle spasms, non-restful sleep, tension headache and presence of mood disorders. FM comorbidity resulted in twelve HT subjects (31%) and none in SCH patient. In particular, FM comorbidity in HT patients without SCH was 33.3% and in HT patients with SCH was 28.5%. Based on our data, we speculate that maybe there is more than a hypothesis regarding the cause-effect relation between thyroid autoimmunity and the presence of FM, thus suggesting a hypothetical role of thyroid autoimmunity in FM pathogenesis.


Asunto(s)
Enfermedades Autoinmunes/etiología , Fibromialgia/inmunología , Enfermedad de Hashimoto/inmunología , Glándula Tiroides/inmunología , Adulto , Estudios de Cohortes , Comorbilidad/tendencias , Femenino , Fibromialgia/epidemiología , Fibromialgia/etiología , Enfermedad de Hashimoto/complicaciones , Enfermedad de Hashimoto/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo
4.
Reumatismo ; 63(3): 165-70, 2011 Nov 09.
Artículo en Italiano | MEDLINE | ID: mdl-22257917

RESUMEN

OBJECTIVE: Fibromyalgia (FM) is characterized by the presence of chronic widespread pain throughout the musculoskeletal system and diffuse tenderness. Unfortunately, no laboratory tests have been appropriately validated for FM and correlated with the subsets and activity. The aim of this study was to apply a proteomic technique in saliva of FM patients: the Surface Enhance Laser Desorption/Ionization Time-of-Flight (SELDI-TOF). METHODS: For this study, 57 FM patients and 35 HC patients were enrolled. The proteomic analysis of saliva was carried out using SELDI-TOF. The analysis was performed using different chip arrays with different characteristics of binding. The statistical analysis was performed using cluster analysis and the difference between two groups was underlined using Student's t-test. RESULTS: Spectra analysis highlighted the presence of several peaks differently expressed in FM patients compared with controls. The preliminary results obtained by SELDI-TOF analysis were compared with those obtained in our previous study performed on whole saliva of FM patients by using electrophoresis. The m/z of two peaks, increased in FM patients, seem to overlap well with the molecular weight of calgranulin A and C and Rho GDP-dissociation inhibitor 2, which we had found up-regulated in our previous study. CONCLUSION: These preliminary results showed the possibility of identifying potential salivary biomarker through salivary proteomic analysis with MALDI-TOF and SELDI-TOF in FM patients. The peaks observed allow us to focus on some of the particular pathogenic aspects of FM, the oxidative stress which contradistinguishes this condition, the involvement of proteins related to the cytoskeletal arrangements, and central sensibilization.


Asunto(s)
Fibromialgia/metabolismo , Proteómica/métodos , Proteínas y Péptidos Salivales/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masas en Tándem/métodos , Adulto , Biomarcadores/análisis , Electroforesis en Gel Bidimensional , Femenino , Fibromialgia/diagnóstico , Fibromialgia/epidemiología , Humanos , Masculino , Trastornos Mentales/epidemiología , Persona de Mediana Edad , Estrés Oxidativo , Índice de Severidad de la Enfermedad , Tiroiditis Autoinmune/epidemiología , Xerostomía/epidemiología , Inhibidor beta de Disociación del Nucleótido Guanina rho/análisis
5.
Clin Exp Rheumatol ; 28(6 Suppl 63): S94-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21176428

RESUMEN

OBJECTIVES: To evaluate the role of spasmophilia (SP) in fibromyalgia syndrome (FM). METHODS: Three hundred and fourteen patients (280 F, 34 M) with a diagnosis of FM or FM and spasmophilia (FM+SP) were recruited. Clinical assessment of patients and controls included the Questionnaires FIQ, HAQ and the tender point (TP) count. Life-time or ongoing psychiatric aspects were evaluated by trained psychiatrists by means of the classic scales: Structured Clinical Interview (SCID) for DSM-IV. The following analysis were evaluated: cytokine (IL1, IL2, IL6, IL8, IL10), TNF-α, cortisol, GH, ACTH, IGF1, 5HT, intracellular Mg, plasma calcium p(Ca), PTH, (25(OH)D) and thyroid functionality. Some typical symptoms were investigated. RESULTS: Eighty-one patients resulted positive for spamophilia (FM+SP), while 233 resulted negative for spasmophilia (FM). The mean TP number resulted higher in the FM group (15.33±3.88) with respect to FM+SP (12.88±6.17, p=0.016), while FIQ and HAQ did not differ between the two studied groups. FM patients exhibited a higher frequency of psychiatric disorders with respect to FM+SP patients (72% FM vs. 49% FM+SP, p<0.01). In particular the frequency of depression was 65.5% FM vs. 35% FM+SP (p<0.01). CONCLUSIONS: The presence of spasmophilia seems to influence psychiatric comorbidity which was less prevalent in FM+SP patients. FM is indeed characterised by an abnormal sensory processing of pain that seems to result from a combination of interactions between neurotransmitters, stress, hormones and the nervous system; spasmophilia would seem to be more linked to a dysfunction at the neuromuscular level.


Asunto(s)
Fibromialgia/epidemiología , Fibromialgia/fisiopatología , Tetania/epidemiología , Tetania/fisiopatología , Adulto , Estudios de Cohortes , Comorbilidad , Citocinas/sangre , Electromiografía , Femenino , Fibromialgia/psicología , Humanos , Italia/epidemiología , Masculino , Trastornos Mentales/epidemiología , Persona de Mediana Edad , Sistema Musculoesquelético/fisiopatología , Sistema Nervioso/fisiopatología , Estudios Retrospectivos , Tetania/psicología
6.
Gut ; 58(5): 679-87, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19136513

RESUMEN

BACKGROUND AND AIMS: Previous studies indicate unrestrained cell cycle progression in liver lesions from hepatocarcinogenesis-susceptible Fisher 344 (F344) rats and a block of G(1)-S transition in corresponding lesions from resistant Brown Norway (BN) rats. Here, the role of the Forkhead box M1B (FOXM1) gene during hepatocarcinogenesis in both rat models and human hepatocellular carcinoma (HCC) was assessed. METHODS AND RESULTS: Levels of FOXM1 and its targets were determined by immunoprecipitation and real-time PCR analyses in rat and human samples. FOXM1 function was investigated by either FOXM1 silencing or overexpression in human HCC cell lines. Activation of FOXM1 and its targets (Aurora Kinose A, Cdc2, cyclin B1, Nek2) occurred earlier and was most pronounced in liver lesions from F344 than BN rats, leading to the highest number of Cdc2-cyclin B1 complexes (implying the highest G(2)-M transition) in F344 rats. In human HCC, the level of FOXM1 progressively increased from surrounding non-tumorous livers to HCC, reaching the highest levels in tumours with poorer prognosis (as defined by patients' length of survival). Furthermore, expression levels of FOXM1 directly correlated with the proliferation index, genomic instability rate and microvessel density, and inversely with apoptosis. FOXM1 upregulation was due to extracellular signal-regulated kinase (ERK) and glioblastoma-associated oncogene 1 (GLI1) combined activity, and its overexpression resulted in increased proliferation and angiogenesis and reduced apoptosis in human HCC cell lines. Conversely, FOXM1 suppression led to decreased ERK activity, reduced proliferation and angiogenesis, and massive apoptosis of human HCC cell lines. CONCLUSIONS: FOXM1 upregulation is associated with the acquisition of a susceptible phenotype in rats and influences human HCC development and prognosis.


Asunto(s)
Carcinoma Hepatocelular/genética , Quinasas MAP Reguladas por Señal Extracelular/genética , Factores de Transcripción Forkhead/genética , Neoplasias Hepáticas/genética , Animales , Carcinoma Hepatocelular/patología , Proliferación Celular , Transformación Celular Neoplásica/genética , Proteína Forkhead Box M1 , Factores de Transcripción Forkhead/fisiología , Regulación Neoplásica de la Expresión Génica/genética , Genes cdc , Predisposición Genética a la Enfermedad/genética , Hígado/patología , Neoplasias Hepáticas/patología , Neovascularización Patológica/etiología , Ratas , Ratas Endogámicas F344 , Activación Transcripcional , Regulación hacia Arriba
7.
Allergy ; 63(11): 1550-8, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18925892

RESUMEN

BACKGROUND: Allergy diagnosis in patients exposed to multiple pollen species is complex and misdiagnosis is often a cause for unsuccessful specific immunotherapy. OBJECTIVE: We studied the sensitization profile of individual allergens (major, minor and pan-allergens) in pollen-sensitized patients in a region with high exposure to olive pollen by investigating the influence of minor allergens on allergic disease and the association between pan- and minor allergen sensitizations. METHODS: A panel of 13 purified allergens, which included the most relevant allergens in the area, as well as minor olive allergens and pan-allergens, were screened using a high-capacity technology (ADVIA-Centaur) in 891 patients. RESULTS: Olive allergy as measured by specific IgE to Ole e 1 was the leading pollinosis in the area. The minor olive allergens Ole e 7 and Ole e 9 were markers of more severe allergic illness. Profilin sensitization was associated mainly with grass allergy, the second most prevalent pollinosis. Salsola kali pollen allergy was the third most common cause of pollinosis in the area. The prevalence of sensitization to the peach allergen Pru p 3, a nonspecific lipid-transfer protein, was notable. CONCLUSION: Epidemiological analysis by component-resolved diagnosis is a new method, which elucidates the interaction between allergen exposure gradient and patient sensitization. High exposure leads to differential sensitization profiles some of which are associated with more severe allergic conditions. Profilin sensitization, related mainly to grass pollinosis, was a marker of more severe grass pollen sensitization.


Asunto(s)
Alérgenos/inmunología , Olea/inmunología , Polen/inmunología , Profilinas/inmunología , Rinitis Alérgica Estacional/epidemiología , Humanos , Inmunoglobulina E/sangre , Epidemiología Molecular , Poaceae/inmunología , Rinitis Alérgica Estacional/diagnóstico , Rinitis Alérgica Estacional/inmunología , España/epidemiología
8.
Rheumatol Int ; 28(3): 295-7, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17684748

RESUMEN

We report on a female case of rheumatoid arthritis (RA) with hepatitis C virus comorbidity. The patient was treated once weekly over ten consecutive weeks with Adacolumn device. Clinical assessment and HCV-RNA concentration were monitored at weeks-1, 4, 9, 14 and during follow-up over 6 months. At the end of the treatment: the number of tender and swollen joints, patient's global assessment of disease activity (VAS), physician's VAS, C-reactive protein (CRP) decreased, respectively; ACR response was >20. This improvement was maintained for over 2 months. At week 38, the patient was re-treated achieving again an ACR response >20.


Asunto(s)
Artritis Reumatoide/epidemiología , Artritis Reumatoide/terapia , Citaféresis/métodos , Hepatitis C Crónica/epidemiología , Tuberculosis/epidemiología , Anciano , Antiinflamatorios no Esteroideos/uso terapéutico , Comorbilidad , Femenino , Granulocitos/metabolismo , Humanos , Italia , Metilprednisolona/uso terapéutico , Monocitos/metabolismo , Piroxicam/uso terapéutico , Inducción de Remisión/métodos , Resultado del Tratamiento
9.
Biochim Biophys Acta ; 1765(2): 126-47, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16216419

RESUMEN

The different frequency of hepatocellular carcinoma (HCC) in humans at risk suggests a polygenic predisposition. However, detection of genetic variants is difficult in genetically heterogeneous human population. Studies on mouse and rat models identified 7 hepatocarcinogenesis susceptibility (Hcs) and 2 resistance (Hcr) loci in mice, and 7 Hcs and 9 Hcr loci in rats, controlling multiplicity and size of neoplastic liver lesions. Six liver neoplastic nodule remodeling (Lnnr) loci control number and volume of re-differentiating lesions in rat. A Hcs locus, with high phenotypic effects, and various epistatic gene-gene interactions were identified in rats, suggesting a genetic model of predisposition to hepatocarcinogenesis with different subset of low-penetrance genes, at play in different subsets of population, and a major locus. This model is in keeping with human HCC epidemiology. Several putative modifier genes in rodents, deregulated in HCC, are located in chromosomal segments syntenic to sites of chromosomal aberrations in humans, suggesting possible location of predisposing loci. Resistance to HCC is associated with lower genomic instability and downregulation of cell cycle key genes in preneoplastic and neoplastic lesions. p16(INK4A) upregulation occurs in susceptible and resistant rat lesions. p16(INK4A)-induced growth restraint was circumvented by Hsp90/Cdc37 chaperons and E2f4 nuclear export by Crm1 in susceptible, but not in resistant rats and human HCCs with better prognosis. Thus, protective mechanisms seem to be modulated by HCC modifiers, and differences in their efficiency influence the susceptibility to hepatocarcinogenesis and probably the prognosis of human HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Predisposición Genética a la Enfermedad , Neoplasias Hepáticas/genética , Animales , Transformación Celular Neoplásica/genética , Humanos
10.
Clin Exp Rheumatol ; 25(2): 225-30, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17543146

RESUMEN

OBJECTIVE: To examine the possible role of the soluble factor in fibromyalgia (FM) by studying the correlation of cytokine levels with the patients' clinical and psychiatric profile. METHODS: Eighty FM patients underwent clinical and psychiatric evaluations, and plasma levels of cytokines (IL-1, IL-6, IL-8, IL-10, TNF-alpha), aspecific markers of inflammation, rheumatoid factor (RF), anti-extractable nuclear antigen (ENA) antibodies, and anti-nuclear factor (FAN) were measured. RESULTS: Higher levels of IL-10, IL-8 and TNF-alpha were found in FM patients than in controls. Significant correlations between the biochemical parameters and clinical data were found. CONCLUSION: The higher levels of cytokines found in FM patients suggest the presence of an inflammatory response system (IRS) and highlight a parallel between the clinical symptoms and biochemical data. They support the hypothesis that cytokines may play a role in the clinical features of fibromyalgia. In addition, the similar cytokine patterns found in FM patients with different psychiatric profiles suggests that IRS impairment may play a specific role in the disease.


Asunto(s)
Fibromialgia/sangre , Fibromialgia/inmunología , Interleucina-10/sangre , Interleucina-8/sangre , Factor de Necrosis Tumoral alfa/sangre , Adulto , Ansiedad/etiología , Biomarcadores/sangre , Estudios de Casos y Controles , Depresión/etiología , Femenino , Fibromialgia/psicología , Regulación de la Expresión Génica , Encuestas Epidemiológicas , Humanos , Inflamación/sangre , Inflamación/fisiopatología , Inflamación/psicología , Interleucina-10/genética , Interleucina-8/genética , Persona de Mediana Edad , Modelos Biológicos , Índice de Severidad de la Enfermedad , Perfil de Impacto de Enfermedad , Factor de Necrosis Tumoral alfa/genética
11.
Eur J Ophthalmol ; 17(2): 223-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17415696

RESUMEN

PURPOSE: To evaluate which Heidelberg Retina Tomograph (HRT) parameter is the best predictor of frequency doubling technology (FDT) sensitivity by using a sector based analysis between FDT and optic nerve head shape parameters such as cup shape measure (CSM) and rim area (RA), which have been shown to have the best correlation with FDT indices among all the HRT parameters. METHODS: One eye was randomly chosen from 100 patients with primary open angle glaucoma (abnormal visual field and/or abnormal optic nerve and untreated intraocular pressure above 21 mm Hg). All the patients were examined with Humphrey field analyzer (HFA), program 24-2, SITA standard, FDT program C 20, and HRT. RA and CSM for the HRT analysis and mean deviation, pattern standard deviation, and the sensitivity of each tested point for the FDT test were considered in this study. All the parameters were calculated as both global and sector measurements. Findings were analyzed using Pearson's correlation coefficient and linear regression model. RESULTS: Significant (p<0.001) correlation was found between FDT indices and HRT RA and CSM. Significant (p<0.001) sector correlation was found between FDT sensitivity and RA and CSM, but when a linear regression model was applied, RA was the most predictive parameter of FDT. Temporal CSM was more strongly correlated to FDT fovea sensitivity than temporal RA. Furthermore, sector HRT parameters were better correlated to HFA than to FDT. CONCLUSIONS: In this glaucomatous group, cup shape measure and RA were significantly correlated to FDT indices. RA was more predictive of FDT abnormality than CSM in all the considered sectors except in the temporal one. However, HFA was a stronger predictor of HRT parameters than FDT.


Asunto(s)
Glaucoma de Ángulo Abierto/diagnóstico , Disco Óptico/patología , Enfermedades del Nervio Óptico/diagnóstico , Trastornos de la Visión/diagnóstico , Campos Visuales , Estudios Transversales , Humanos , Presión Intraocular , Sensibilidad y Especificidad , Tomografía/métodos , Pruebas del Campo Visual/métodos
12.
Cancer Res ; 35(11 Pt 1): 3041-7, 1975 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-241483

RESUMEN

Different functional and structural properties of rat liver microsomes were studied during hepatocarcinogenesis induced by 0.25% DL-ethionine. During the first to fourth months of ethionine feeding, great decreases of cytochrome P-450 content, reduced nicotinamide adenine dinucleotide phosphate-dependent lipid peroxidation, and animopyrine demethylase activity occurred. No changes in the reduced nicotinamide adenine dinucleotide phosphate-cytochrome c reductase activity were observed. These functional alterations were paralleled by an increase in membrane-free ribosomes and by changes in the relative proportions of phospholipid fatty acids in microsomes. After the end of ethionine feeding, when hyperplastic nodules and/or hepatomas were present, the above functional and structural parameters were studied in the latter tissues, as well as in surrounding nonodular liver. Decreases in cytochrome P-450 content, lipid peroxidation, and animopyrine demethylase activity were documented in hyperplastic nodules and hepatomas. In hepatomas, the alterations were more marked and decrease of reduced nicotinamide adenine dinucleotide phosphate-cytochrome c reductase activity was also found. All these functional parameters were quite normal in surrounding nonnodular liver. Similarly, alterations in phospholipid fatty acid composition disappeared in surrounding nonnodular liver, but they partially persisted in both hyperplastic nodules and hepatomas. In contrast, the increase in membrane-free ribosomes also occurred in surrounding nonnodular liver, although to a lower extent than in hyperplastic nodules and hepatomas. These data are discussed in relation to the problem of the cellular precursors of hepatomas.


Asunto(s)
Carcinoma Hepatocelular/inducido químicamente , Retículo Endoplásmico/efectos de los fármacos , Etionina , Neoplasias Hepáticas/inducido químicamente , Microsomas Hepáticos/efectos de los fármacos , Animales , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Sistema Enzimático del Citocromo P-450/metabolismo , Dieta , Transporte de Electrón , Ácidos Grasos/metabolismo , Femenino , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , NADP , NADPH-Ferrihemoproteína Reductasa/metabolismo , Fosfolípidos/metabolismo , Ratas , Ribosomas/efectos de los fármacos
13.
Cancer Res ; 44(8): 3419-25, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6331645

RESUMEN

Human skin fibroblasts isolated in vitro from subjects carrying the Mediterranean variant of glucose-6-phosphate dehydrogenase exhibit an 85% decrease of this enzymatic activity. There is a 26% and a 94% decrease of the hexose monophosphate shunt and of the reduced nicotinamide adenine dinucleotide phosphate/nicotinamide adenine dinucleotide phosphate ratio, respectively. Incubation with 0.1 mM methylene blue activates the hexose monophosphate shunt 7 times that of normal fibroblasts and only 2.2 times that of glucose 6-phosphate-deficient cells. This behavior is coupled with an increase of the resistance to cell death induced by benzo(a)pyrene, a carcinogen, the activation of which proceeds through a reduced nicotinamide adenine dinucleotide phosphate-dependent arene oxide formation. In contrast, no difference between the normal and the deficient fibroblasts exists as regards the toxic effect of methylnitrosourea, a carcinogen that does not need metabolic activation. A growth-retarding effect of benzo(a)pyrene was observed in both normal and deficient cells during 9 days in vitro. This effect is lower in the fibroblasts carrying the Mediterranean glucose-6-phosphate dehydrogenase variant. Glucose-6-phosphate dehydrogenase deficiency protects human fibroblasts against the benzo(a)pyrene-induced in vitro transformation. This effect is mimicked by the incubation of normal fibroblasts with dehydroepiandrosterone, a strong inhibitor of glucose-6-phosphate dehydrogenase. The deficiency of this enzymatic activity, either genetically transmitted or induced by dehydroepiandrosterone, is coupled with a reduced rate of benzo(a)pyrene conversion to water-soluble metabolites by human skin fibroblasts.


Asunto(s)
Benzopirenos/toxicidad , Carcinógenos/toxicidad , Transformación Celular Neoplásica , Deficiencia de Glucosafosfato Deshidrogenasa/fisiopatología , Piel/fisiopatología , Benzo(a)pireno , Benzopirenos/metabolismo , Biotransformación , Células Cultivadas , Fibroblastos/fisiología , Glucosafosfato Deshidrogenasa/metabolismo , Humanos , Cinética , Masculino , Valores de Referencia
14.
Cancer Res ; 52(18): 4979-86, 1992 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-1516054

RESUMEN

Previous work has shown a consistent fall in S-adenosyl-L-methionine (SAM) in the liver of diethylnitrosamine-initiated rats, during the development of preneoplastic lesions, in persistent nodules (PNs), and hepatocellular carcinomas. The injection of SAM into rats causes the reconstitution of the SAM pool, coupled with growth restraint, remodeling, and apoptosis of preneoplastic cells, and inhibits the development of PNs and hepatocellular carcinomas. To evaluate if SAM treatment causes a long-term prevention of preneoplastic and neoplastic liver lesions or merely causes a delay in their development, we evaluated the effect of a relatively short SAM treatment on the development of preneoplastic and neoplastic lesions in a long-term study. Male Wistar rats were subjected to initiation with diethylnitrosamine, followed by selection and then by the administration of phenobarbital for 16 weeks. After selection, the rats were given i.m. injections of a purified SAM preparation (384 mumol/kg/day) for 24 weeks. In SAM-treated rats, a decrease in the incidence of PNs was found 6, 14, and 24-28 months after initiation. At the end of SAM treatment the number of PNs per rat liver, nodule diameter, and labeling and mitotic indices of nodular cells decreased considerably in control rats. Nodule diameter started to increase rapidly again only 8 months after arresting SAM treatment, when complete recovery of DNA synthesis in nodular cells occurred. The majority of nodules present in the liver 6-28 months after initiation belonged to the clear and acidophilic cell types, with lower percentages of mixed cell and basophilic cell types. A decrease in basophilic nodules occurred in SAM-treated rats. Fourteen and 24-28 months after initiation hepatocellular carcinoma incidence was 11 of 12 and 10 of 10 in control rats, respectively, and only 1 of 12 and 3 of 11 in SAM-treated rats. At the 24th-28th month all control rats had tumors identified as 2 poorly differentiated carcinomas, 6 trabecular carcinomas, or 3 adenocarcinomas, while only 2 relatively small trabecular carcinomas and 1 small glandular tumor developed in SAM-treated rats. In 3 of 11 SAM-treated rats, but in none of the control rats, leukemic infiltration of liver occurred 24-28 months after initiation. Leukemic infiltration of the spleen occurred in 5 and 3 control and SAM-treated rats, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Neoplasias Hepáticas Experimentales/prevención & control , Neoplasias Hepáticas/prevención & control , Lesiones Precancerosas/prevención & control , S-Adenosilmetionina/uso terapéutico , Animales , Neoplasias Hepáticas/patología , Neoplasias Hepáticas Experimentales/patología , Masculino , Índice Mitótico/efectos de los fármacos , Lesiones Precancerosas/patología , Ratas , Ratas Endogámicas , Factores de Tiempo
15.
Cancer Res ; 49(7): 1850-6, 1989 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-2564313

RESUMEN

The resistant hepatocyte model (initiation/selection) and the triphasic model (initiation/selection followed by phenobarbital, for a maximum of 16 weeks) were compared for their ability to generate enzyme-altered foci (EAF) and nodules in the liver of Wistar rats initiated by diethylnitrosamine. The effects of S-adenosyl-L-methionine (SAM) on the development of preneoplastic tissue was tested in these experimental models. In the absence of phenobarbital (PB), EAF and early nodules (EN) went through a phase of rapid growth, between 4 and 9 weeks after initiation, to a phase in which progressive decrease in number and size occurred. By the 26th week only a few remodeling EAF and nodules were found. In PB-treated rats a rapid increase in the percentage of liver occupied by EAF and EN, up to the 9th week after initiation, was followed by a period of slow growth (from the 9th to the 20th week) and then, after PB withdrawal (20th week), by a drop in the number and size of EAF and EN. However, at the 26th week actively growing nodules with a low tendency to spontaneous remodeling (persistent nodules) developed. EAF and EN showed a high DNA synthesis 5 weeks after initiation. Thereafter, progressive decline in DNA synthesis, coupled with remodeling and decrease in number of biochemical markers, was seen both in the absence and, even though to a lesser extent, in the presence of PB, indicating that preneoplastic lesions became increasingly insensitive to PB. Relatively few apoptotic bodies could be observed in EAF and EN during PB treatment. After PB withdrawal, decrease in growth potential was coupled with increase in apoptotic bodies. In contrast, in persistent nodules relatively high apoptosis occurred which partially counterbalanced high DNA synthesis. Administration of SAM for a maximum of 16 weeks, starting at the 4th week after initiation, caused a great decrease in number and size of EAF and EN, associated with inhibition of DNA synthesis, high cell death by apoptosis, high remodeling, and loss of biochemical markers, in preneoplastic lesions of both PB-treated and untreated rats. A 1-8-week SAM treatment, started after the development of persistent nodules, caused a great regression of nodular lesions, coupled with a sharp fall in DNA synthesis and increase in apoptosis. It is suggested that inhibition by SAM of the development of preneoplastic tissue is linked to a shift of the equilibrium between cell production and cell death in favor of cell death.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Desoxiadenosinas , Neoplasias Hepáticas Experimentales/patología , Lesiones Precancerosas/patología , S-Adenosilmetionina/farmacología , Adenosina/análogos & derivados , Adenosina/análisis , Animales , ADN/biosíntesis , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/prevención & control , Masculino , Fagocitosis , Fenobarbital/farmacología , Fenotipo , Lesiones Precancerosas/inducido químicamente , Lesiones Precancerosas/prevención & control , Proto-Oncogenes , Ratas , Ratas Endogámicas , Tionucleósidos/análisis , gamma-Glutamiltransferasa/análisis
16.
Cancer Res ; 59(18): 4651-7, 1999 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10493520

RESUMEN

Neoplastic liver nodules and hepatocellular carcinomas (HCCs) were induced, by "resistant hepatocyte" model, 32 and 70 weeks after initiation with diethylnitrosamine, respectively, in F344 Brown Norway (BN), and (BNxF344)F1 rats. Nodule number/liver (N) did not significantly differ among rat strains, whereas nodule mean volume (V) and nodule volume fraction (VF) were higher in susceptible F344 than in resistant BN and BFF1 strains and were predictive of subsequent development of HCCs. Genomic scanning of 157 backcross BFF1xF344 rats with 190 polymorphic microsatellites, and linkage analysis, revealed two quantitative trait loci (QTL) on chromosomes 7 and 10, which showed significant linkage with VF, and two QTL on chromosomes 4 and 8, which showed suggestive linkage with V and VF. On the basis of phenotypic patterns of homozygous and heterozygous backcross progeny and of allelic distribution pattern, QTL on chromosomes 10, 8, and 4 were tentatively identified as resistance loci, and QTL on chromosome 7 was identified as susceptibility locus for rat hepatocarcinogenesis. An analysis of interactions allowed us to identify additional putative QTL on chromosomes 5 and 8 and suggested an additive effect of loci on chromosomes 10, 8, and 4 for VF and V. These data are the first to identify chromosomal regions containing putative susceptibility/resistance loci for rat hepatocarcinogenesis, which seems to be highly complex in terms of the number of genetic factors involved.


Asunto(s)
Mapeo Cromosómico , Neoplasias Hepáticas Experimentales/genética , Hígado/patología , Animales , Carcinógenos/toxicidad , Cruzamientos Genéticos , Dietilnitrosamina/toxicidad , Femenino , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Genotipo , Hígado/efectos de los fármacos , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/patología , Masculino , Fenotipo , Ratas , Ratas Endogámicas BN , Ratas Endogámicas F344
17.
Biochim Biophys Acta ; 413(1): 116-34, 1975 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-172147

RESUMEN

The cholesterol to phospholipid ratio in mitochondria from hepatomas AH-130, 3924A and 5123 is higher than in the particles isolated from adult or fetal rat livers. Nearly all the cholesterol of hepatoma mitochondria is located in membranes. As in liver mitochondria, in the particles isolated from hepatoma AH-130 there is more cholesterol in the outer than in the inner membrane. In mitochondria from cholesterol-enriched liver and hepatomas, there occurs a decrease in extent of hypoosmotic and phosphate-induced swelling and a decrease of conformational changes linked to energy states. The phenomenon is more marked in particles which exhibit higher cholesterol to phospholipid ratios. A statistically significant negative correlation exists between the cholesterol to phospholipid ratio and extent of volume or conformational changes. No significant modifications of these parameters were found in fetal liver mitochondria. Cholesterol content does not influence K+ uptake by cholesterol-enriched or hepatoma mitochondria. Nor does cholesterol content affect the respiratory increment related to this uptake. As a consequence of K+ uptake, total mitochondrial water exchangeable with tritiated water rises 20% while sucrose-impermeable water rises 42-48% in both adult rat liver and hepatoma AH-130 mitochondria. Absorbance changes linked to ion uptake do not correspond merely to variations in mitochondrial water content. Water content is apparently not influenced by the cholesterol to phospholipid ratio. However, the ratio is significantly correlated to both extent and initial rate of absorbance decrease of mitochondrial suspensions during K+ uptake. The higher the ratio, the lower the extent and initial rate of absorbance decrease.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Colesterol/metabolismo , Mitocondrias Hepáticas/metabolismo , Animales , Reductasas del Citocromo/metabolismo , Dieta , Femenino , Feto/metabolismo , Neoplasias Hepáticas , Magnesio/farmacología , Malato Deshidrogenasa/metabolismo , Masculino , Membranas/metabolismo , Dilatación Mitocondrial/efectos de los fármacos , Neoplasias Experimentales/metabolismo , Concentración Osmolar , Consumo de Oxígeno , Fosfatos/farmacología , Potasio/metabolismo , Ratas , Ratas Endogámicas ACI , Valinomicina/farmacología , Agua/metabolismo
18.
Biochim Biophys Acta ; 504(1): 1-14, 1978 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-213108

RESUMEN

The phospholipid depletion of rat liver mitochondria, induced by acetoneextraction or by digestion with phospholipase A2 or phospholipase C, greatly inhibited the activity of NADH-cytochrome c reductase (rotenone-insensitive). A great decrease of the reductase activity also occurred in isolated outer mitochondrial membranes after incubation with phospholipase A2. The enzyme activity was almost completely restored by the addition of a mixture of mitochondrial phospholipids to either lipid-deficient mitochondria, or lipid-deficient outer membranes. The individual phospholipids present in the outer mitochondrial membrane induced little or no stimulation of the reductase activity. Egg phosphatidylcholine was the most active phospholipid, but dipalmitoyl phosphatidylcholine was almost ineffective. The lipid depletion of mitochondria resulted in the disappearance of the non-linear Arrhenius plot which characterized the native reductase activity. A non-linear plot almost identical to that of the native enzyme was shown by the enzyme reconstituted with mitochondrial phospholipids. Triton X-100, Tween 80 or sodium deoxycholate induced only a small activation of NADH-cytochrome c reductase (rotenone-insensitive) in lipid-deficient mitochondria. The addition of cholesterol to extracted mitochondrial phospholipids at a 1 : 1 molar ratio inhibited the reactivation of NADH-cytochrome c reductase (rotenone-insensitive) but not the binding of phospholipids to lipid-deficient mitochondria or lipid-deficient outer membranes. These results show that NADH-cytochrome c reductase (rotenone-insensitive) of the outer mitochondrial membrane requires phospholipids for its activity. A mixture of phospholipids accomplishes this requirement better than individual phospholipids or detergents. It also seems that the membrane fluidity may influence the reductase activity.


Asunto(s)
Reductasas del Citocromo/metabolismo , Mitocondrias Hepáticas/enzimología , Fosfolípidos/fisiología , Animales , Colesterol/farmacología , Grupo Citocromo c , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/enzimología , Cinética , Fosfolipasas/farmacología , Fosfolípidos/farmacología , Unión Proteica , Ratas , Rotenona/farmacología
19.
Br J Ophthalmol ; 89(4): 425-9, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15774918

RESUMEN

AIM: To evaluate the efficacy and safety of a stainless steel miniature glaucoma drainage device (Ex-PRESS R50) for the surgical treatment of primary open angle glaucoma (POAG) and cataract when combined with phacoemulsification. METHODS: Clinical, prospective, multicentre, single treatment arm, non-randomised, non-masked study. The Ex-PRESS device was implanted at the limbus under a conjunctival flap. Phacoemulsification cataract extraction and in the bag IOL implantation were performed through clear cornea temporally. PRIMARY OUTCOME: IOP change; secondary outcomes: side effects and VA changes. RESULTS: 26 eyes of 25 patients were implanted with the device. The mean (SD) follow up was 23.9 (10.4) months and the mean age was 75.1 (7.1) years. 17/26 eyes have more than 3 years of follow up. One case was discontinued because of device removal, one because of death, and three were lost to follow up. EFFICACY: preoperative IOP was 21 (4) mm Hg; at 1, 2, and 3 years IOP was 15.3 (3.1) mm Hg (35% reduction), 16.6 (2.7) mm Hg (29% reduction), and 16 (2.6) mm Hg (22% reduction) respectively. Kaplan-Meyer determined overall success rate (IOP < or = 21 mm Hg at the last visit with or without medications) as 76.9%. The number of antiglaucoma medications was reduced by 95% at year 1. Only six patients (23%) were taking IOP lowering treatment at their last visit, five with one medication and one with two medications. Side effects: early postoperative complications were clinically mild and included six cases of hypotony (IOP <5 mm Hg), three cases of hyphaema (<2 mm) with no clinically significant further effects. Long term complications were two cases (7.7%) of device rotation (one treated by reposition) and three cases (11.5%) of conjunctival erosion at 2 and 3 years. CONCLUSIONS: The Ex-PRESS implant, combined with phacoemulsification cataract extraction, is clinically safe and effective, maintaining in the long term a large reduction in IOP and in the number of antiglaucoma medications.


Asunto(s)
Catarata/complicaciones , Implantes de Drenaje de Glaucoma , Glaucoma de Ángulo Abierto/cirugía , Facoemulsificación , Anciano , Anciano de 80 o más Años , Antihipertensivos/administración & dosificación , Esquema de Medicación , Cirugía Filtrante/efectos adversos , Cirugía Filtrante/métodos , Estudios de Seguimiento , Glaucoma de Ángulo Abierto/complicaciones , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Presión Intraocular , Cuidados Posoperatorios/métodos , Estudios Prospectivos , Diseño de Prótesis , Falla de Prótesis , Acero Inoxidable , Agudeza Visual
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