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1.
J Synchrotron Radiat ; 26(Pt 1): 272-279, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30655495

RESUMEN

A new diffractometer is now available to the general user community at the ESRF. The new diffractometer is a side station of the high-resolution inelastic X-ray scattering spectrometer on beamline ID28 and is located in the same experimental hutch. Both instruments can be operated simultaneously. The new diffractometer combines a fast and low-noise hybrid pixel detector with a variable diffraction geometry. The beam spot on the sample is 50 µm × 50 µm, where focusing is achieved by a combination of Be lenses and a KB mirror. Wavelengths from 0.5 to 0.8 Šcan be used for the diffraction experiments. The setup is compatible with a variety of sample environments, allowing studies under non-ambient conditions. The diffractometer is optimized to allow a rapid survey of reciprocal space and diffuse scattering for the identification of regions of interest for subsequent inelastic scattering studies, but can also be employed as a fully independent station for structural studies from both powder and single-crystal diffraction experiments. Several software packages for the transformation and visualization of diffraction data are available. An analysis of data collected with the new diffractometer shows that the ID28 side station is a state-of-the-art instrument for structural investigations using diffraction and diffuse scattering experiments.

2.
World J Microbiol Biotechnol ; 34(11): 162, 2018 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-30368630

RESUMEN

This study was conducted to report the richness of endophytic Penicillium and Talaromyces species isolated from Tillandsia catimbauensis, a bromeliad endemic in the Brazilian tropical dry forest (Caatinga), to verify their ability to produce the enzyme L-asparaginase and to partially optimise the production of biomass and L-asparaginase of the best enzyme producer. A total of 184 endophytes were isolated, of which 52 (29%) were identified through morphological and phylogenetic analysis using ß-tubulin sequences into nine putative species, four in Penicillium and five in Talaromyces. Talaromyces diversus and T. cf. cecidicola were the most frequent taxa. Among the 20 endophytic isolates selected for L-asparaginase production, 10 had the potential to produce the enzyme (0.50-2.30 U/g), especially T. cf. cecidicola URM 7826 (2.30 U/g) and Penicillium sp. 4 URM 7827 (1.28 U/g). As T. cf. cecidicola URM 7826 exhibited significant ability to produce the enzyme, it was selected for the partial optimisation of biomass and L-asparaginase production. Results of the 23 factorial experimental design showed that the highest dry biomass (0.66 g) was obtained under pH 6.0, inoculum concentration of 1 × 108 and 1% L-proline. However, the inoculum concentration was found to be statistically significant, the pH was marginally significant and the concentration of L-proline was not statistically significant. L-Asparaginase production varied between 0.58 and 1.02 U/g and did not reach the optimal point for enzyme production. This study demonstrates that T. catimbauensis is colonised by different Penicillium and Talaromyces species, which are indicated for enzyme production studies.


Asunto(s)
Asparaginasa/biosíntesis , Endófitos/enzimología , Proteínas Fúngicas/biosíntesis , Penicillium/enzimología , Talaromyces/enzimología , Tillandsia/microbiología , Asparaginasa/genética , Brasil , Endófitos/genética , Endófitos/aislamiento & purificación , Bosques , Proteínas Fúngicas/genética , Penicillium/genética , Penicillium/aislamiento & purificación , Filogenia , Talaromyces/genética , Talaromyces/aislamiento & purificación
3.
Pharmacogenomics J ; 17(2): 146-154, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-26856250

RESUMEN

The search for biomarkers of response to antipsychotic medications is hindered by difficulties inherent in the topic or related to persistent methodological difficulties, such as high rates of anticipated discontinuation and consequent distortions in the imputation of missing data. Because early response to antipsychotics represents a sufficiently reliable index of the subsequent treatment response in patients with schizophrenia, we undertook a real-world, genome-wide association study (GWAS) with the aim of identifying genetic predictors of response to risperidone after 2 weeks in 86 patients with schizophrenia. Limited to the associations reaching significance in the GWAS, confirmatory analysis relative to risperidone response over 9 months was also designed involving 97 patients (European only) enroled in the CATIE (Clinical Antipsychotic Trials of Intervention Effectiveness) genetic substudy. The GWAS revealed a significant association (false discovery rate 0.02) of the single-nucleotide polymorphism rs2133450 inside the GRM7 gene with Emsley's positive domain derived from the positive and negative syndrome scale (PANSS). Patients with the rs2133450 CC genotype presented poorer improvement in the positive domain over 2 weeks, with odds ratios of 12.68 (95% CI, 3.51-45.76) and 6.95 (95% confidence interval (CI), 2.37-20.37) compared with patients with the AA and AC genotypes, respectively. Compared with A homozygotes, rs2133450 C homozygotes enroled in the CATIE-derived confirmatory analysis showed less improvement in Emsley's positive, excited and depression domains, positive and general PANSS subtypes, and total PANSS after 9 months of treatment with risperidone. The original GWAS and the CATIE-derived confirmatory analysis support the proposal that the rs2133450 may have translational relevance as a predictor of response to risperidone.


Asunto(s)
Antipsicóticos/uso terapéutico , Pruebas de Farmacogenómica/métodos , Variantes Farmacogenómicas , Polimorfismo de Nucleótido Simple , Receptores de Glutamato Metabotrópico/genética , Risperidona/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Psicología del Esquizofrénico , Adulto , Femenino , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genotipo , Heterocigoto , Homocigoto , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Farmacogenética , Fenotipo , Valor Predictivo de las Pruebas , Factores de Riesgo , Esquizofrenia/diagnóstico , Esquizofrenia/genética , Factores de Tiempo , Resultado del Tratamiento
4.
Reprod Domest Anim ; 50(1): 91-6, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25414137

RESUMEN

This study sought to verify the presence of membranous vesicles in cat seminal plasma by means of transmission electron microscopy and to identify protein profile and some of the enzymatic activities associated with these particles. The transmission electron microscopy observations showed the existence of different sized vesicular membranous structures of more or less spherical shape. These vesicles were surrounded by single-, double- or multiple-layered laminar membranes. The vesicle diameters ranged from 16.3 to 387.4 nm, with a mean of 116.5 ± 70.7 nm. Enzyme activity determinations showed the presence of dipeptilpeptidase IV, aminopeptidase, alkaline and acid phosphatase. To our knowledge, this is the first report that identifies and characterizes the membranous vesicles in cat seminal plasma. However, further studies are necessary to identify the exact site of production of these membranous vesicles in the cat male genital tract and to determine their specific roles in the reproductive events of this species.


Asunto(s)
Gatos , Vesículas Citoplasmáticas/química , Vesículas Citoplasmáticas/ultraestructura , Proteínas/análisis , Semen/química , Fosfatasa Ácida/análisis , Fosfatasa Alcalina/análisis , Aminopeptidasas/análisis , Animales , Vesículas Citoplasmáticas/enzimología , Dipeptidil Peptidasa 4/análisis , Masculino , Microscopía Electrónica de Transmisión , Semen/enzimología
5.
Acta Psychiatr Scand ; 129(6): 461-6, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23957507

RESUMEN

OBJECTIVE: Several studies have shown that vascular endothelial growth factor (VEGF) is implicated in different neuronal processes involved in major depressive disorder (MDD) and in the mechanisms of action of antidepressants. The aim of this study was to investigate whether VEGF serum levels before treatment might be associated with the antidepressant response. METHOD: Two groups of patients were enrolled. One was composed of 50 MDD patients receiving an antidepressant drug treatment. Illness severity was measured before the treatment (T0) and after 12 weeks (T1). The second group was composed of 67 treatment-resistant depressed (TRD) patients undergoing electroconvulsive therapy (ECT). Illness severity was assessed before the treatment (T0) and 1 month after the end of ECT (T1). Blood samples for VEGF measurements were collected for both groups at the baseline (T0). RESULTS: A significant correlation was observed between baseline VEGF serum levels and the percentage reduction in depressive symptomatology after ECT (P = 0.003). In particular, VEGF levels at baseline were significantly lower in patients showing no response to ECT at follow-up (P = 0.008). No correlation between T0 VEGF concentrations and drug treatment outcome was found. CONCLUSION: Our results suggest that VEGF plays a role in the mechanism of response to ECT.


Asunto(s)
Antidepresivos/farmacología , Trastorno Depresivo Mayor , Trastorno Depresivo Resistente al Tratamiento , Terapia Electroconvulsiva/métodos , Resultado del Tratamiento , Factores de Crecimiento Endotelial Vascular/sangre , Adulto , Anciano , Antidepresivos/administración & dosificación , Biomarcadores/sangre , Trastorno Depresivo Mayor/sangre , Trastorno Depresivo Mayor/terapia , Trastorno Depresivo Resistente al Tratamiento/sangre , Trastorno Depresivo Resistente al Tratamiento/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
6.
Cancer Treat Rev ; 126: 102735, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38613871

RESUMEN

Since colon cancer has a high rate of shedding of tumour fragments into the blood, several research efforts are now focused on the investigation of the minimal residual disease through the detection of ctDNA to tailor the adjuvant therapy of colon cancer patients and optimize its cost/effectiveness balance. The negative prognostic impact of detectable ctDNA in patients' blood after radical surgery for colon cancer is well established. Several clinical trials adopting heterogeneous designs and techniques are now ongoing to translate promises into daily practice by answering five general questions: i) is a ctDNA-guided decision making efficacious in the post-operative management of colon cancer patients? ii) are de-escalation strategies possible in ctDNA-negative cases? iii) are escalation strategies useful to improve the prognosis of ctDNA-positive patients? iv) when MRD is identified at the end of the adjuvant chemotherapy, is another post-adjuvant systemic therapy efficacious? v) can we exploit ctDNA technologies in the follow up of colon cancer patients? This review focuses on currently ongoing trials and how their results may affect the ctDNA "liquid revolution" of early colon cancer.


Asunto(s)
ADN Tumoral Circulante , Neoplasias del Colon , Humanos , Neoplasias del Colon/tratamiento farmacológico , Quimioterapia Adyuvante/métodos , ADN Tumoral Circulante/sangre , Pronóstico , Ensayos Clínicos como Asunto , Biomarcadores de Tumor/genética , Neoplasia Residual
7.
ESMO Open ; 9(4): 102996, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38613911

RESUMEN

BACKGROUND: Targeted therapy (TT) with encorafenib and cetuximab is the current standard for patients with BRAFV600E-mutated metastatic colorectal cancer (mCRC) who received one or more prior systemic treatments. However, the median progression-free survival (mPFS) is ∼4 months, and little is known about the possibility of administering subsequent therapies, their efficacy, and clinicopathological determinants of outcome. METHODS: A real-world dataset including patients with BRAFV600E-mutated mCRC treated with TT at 21 Italian centers was retrospectively interrogated. We assessed treatments after progression, attrition rates, and outcomes. RESULTS: Of the 179 patients included, 85 (47%), 32 (18%), and 7 (4%) received one, two, or three lines of treatment after TT, respectively. Those receiving TT in the second line were more likely to receive at least one subsequent therapy (53%), as compared with those treated with TT in the third line or beyond (30%; P < 0.0001), and achieved longer postprogression survival (PPS), also in a multivariate model (P = 0.0001). Among 62 patients with proficient mismatch repair/microsatellite stable (pMMR/MSS) tumors receiving one or more lines of treatment after second-line TT, combinatory chemotherapy ± anti-vascular endothelial growth factor (anti-VEGF) was associated with longer PFS and PPS as compared with trifluridine-tipiracil or regorafenib (mPFS: 2.6 versus 2.0 months, P = 0.07; PPS: 6.5 versus 4.4 months, P = 0.04). CONCLUSIONS: Our real-world data suggest that TT should be initiated as soon as possible after the failure of first-line treatment in BRAFV600E-mutated mCRC. Among patients with pMMR/MSS tumors, combinatory chemotherapy ± anti-VEGF appears the preferred treatment choice after TT failure.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Carbamatos , Cetuximab , Neoplasias Colorrectales , Mutación , Proteínas Proto-Oncogénicas B-raf , Sulfonamidas , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Cetuximab/uso terapéutico , Cetuximab/farmacología , Masculino , Femenino , Proteínas Proto-Oncogénicas B-raf/genética , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Carbamatos/uso terapéutico , Carbamatos/farmacología , Sulfonamidas/uso terapéutico , Sulfonamidas/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Progresión de la Enfermedad , Supervivencia sin Progresión , Adulto , Anciano de 80 o más Años , Metástasis de la Neoplasia , Italia
8.
Reprod Domest Anim ; 48(2): 252-7, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22774777

RESUMEN

The objectives of this study were to verify the presence of membranous vesicles (MV) in canine seminal plasma by mean of transmission electron microscopy (TEM), to describe the ultrastructural characteristics and to identify some enzymatic activity associated with them. Semen samples, collected by digital manipulation from dogs with proven fertility, were pooled and used for membrane vesicles preparation according to conventional procedures. TEM observations showed the existence of vesicular membranous structures of more or less spherical shape with different sizes. These vesicles were surrounded by a single-, double- or multiple-layered laminar membranes. The mean vesicle diameter was 117.6 ± 86.9 nm ranging from 24.4 to 716.6 nm. Enzyme activity determinations showed the presence of adenosine deaminase, 5'-nucleotidase, ADPase, ATPase, dipeptilpeptidase IV, alkaline phosphatase, total acid phosphatase and prostatic acid phosphatase, while the aminopeptidase activity was absent. In conclusion, results of this study, compatible with results from other mammals, showed for the first time the presence of MV, their ultrastructural and enzymatic characteristics in dog seminal plasma.


Asunto(s)
Perros/fisiología , Semen/fisiología , Animales , Masculino , Membranas/enzimología , Membranas/ultraestructura
9.
Reumatismo ; 64(3): 151-7, 2012 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-22842298

RESUMEN

Fibromyalgia (FM) is a chronic disorder caused by a dysfunction of central nervous system sensitization. This syndrome is characterized by widespread pain and diffuse tenderness, but often also presents fatigue, sleep disturbances, and a whole range of symptoms such as morning stiffness, decreased physical function and dyscognition. FM is usually treated with pharmacological and non-pharmacological treatments. The non-pharmacological interventions include cognitive behavioral therapy (CBT), physiotherapy, acupuncture and patient education programs. In order to evaluate the efficacy of CBT and compare it with other non-pharmacological treatments, we performed a review of the meta-analytic literature. We evaluated the methodological quality of publications found by following the recommendations of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Data showed that CBT does not provide better results than other non-pharmacological treatments on outcomes of pain, fatigue, sleep disturbance and quality of life, at either a short or long-term evaluation. On the contrary, CBT seems to be more effective on symptoms of depression for a short period, whereas it considerably improves the pain self-management and reduces the number of visits to the doctor. The data currently available indicate that cost-effectiveness studies could help us to understand whether the reduction in the number of visits to the doctor could balance the cost of CBT to the health public system.


Asunto(s)
Fibromialgia , Calidad de Vida , Terapia Cognitivo-Conductual , Fatiga , Fibromialgia/terapia , Humanos , Manejo del Dolor , Resultado del Tratamiento
10.
Sci Rep ; 9(1): 11532, 2019 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-31395895

RESUMEN

In this study, we explored vagally-mediated heart rate variability (vmHRV) responses, a psychophysiological index of cognitive self-regulatory control, to map the dynamics associated with empathic responses for pain towards an out-group member. Accordingly, Caucasian participants were asked to judge the experience of African and Caucasian actors touched with either a neutral or a harmful stimulus. Results showed that (1) explicit judgment of pain intensity in African actors yielded higher rating score and (2) took longer time compared to Caucasian actors, (3) these behavioural outcomes were associated with a significant increment of RMSSD, Log-HF-HRV and HF-HRV n.u., (4) resting HF-HRV n.u. predicted the participants' lag-time to judge painful stimulations delivered to African actors. Interestingly, these dynamics were associated with a measure of implicit racial attitudes and were, in part, abolished when participants performed a concurrent task during videos presentation. Taken together our results support the idea that a cognitive effort is needed to self-regulate our implicit attitude as predicted by the 'Contrasting Forces Model'.


Asunto(s)
Frecuencia Cardíaca/fisiología , Juicio/fisiología , Racismo/psicología , Conducta Social , Adulto , Empatía/fisiología , Femenino , Humanos , Masculino , Grupos Raciales/psicología , Descanso/fisiología , Nervio Vago/fisiología , Población Blanca/psicología , Adulto Joven
11.
Amino Acids ; 35(2): 283-9, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18163175

RESUMEN

Cyclo(His-Pro) is an endogenous cyclic dipeptide structurally related to tyreotropin-releasing hormone that was originally discovered in brain. In the central nervous system it has been described to exert multiple biological activities, which seem to be related to a presynaptic dopaminergic mechanism and include among the others a leptin-like function. It can be found in several body fluids and in the gastrointestinal tract where it has been suggested to act as a gut peptide with influence on the entero-insular axis. The oral administration of cyclo(His-Pro) and zinc was described to improve with a synergistic mechanism the glycaemic control in diabetes. The most intriguing function of this cyclic dipeptide is related with its neuroprotective role that was first reported in traumatic injuries of the spinal cord, and then confirmed in other models of experimental injuries of the nervous system. The mechanism that lies behind the neuroprotective activity of cyclo(His-Pro) remain poorly understood. Recent in vitro studies on rat pheochromocytoma PC12 cells have shown that it is a protective factor against stress stimuli and there is early pre-clinical evidence strongly suggesting that it enhances the expression of small heat shock proteins and antioxidant protection at the cellular level. Future research is underway to better characterize the possible use of this cyclic dipeptide in the therapy of neurodegenerative and metabolic disorders.


Asunto(s)
Antioxidantes/química , Antioxidantes/fisiología , Neuronas/metabolismo , Péptidos Cíclicos/química , Péptidos Cíclicos/fisiología , Piperazinas/química , Animales , Antioxidantes/farmacología , Dipéptidos/química , Dipéptidos/farmacología , Dipéptidos/fisiología , Humanos , Estructura Molecular , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Péptidos Cíclicos/farmacología , Piperazinas/farmacología
12.
Mol Cytogenet ; 11: 2, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29344089

RESUMEN

BACKGROUND: The majority of the cases of bone marrow failure syndromes/aplastic anaemias (BMFS/AA) are non-hereditary and considered idiopathic (80-85%). The peripheral blood picture is variable, with anaemia, neutropenia and/or thrombocytopenia, and the patients with idiopathic BMFS/AA may have a risk of transformation into a myelodysplastic syndrome (MDS) and/or an acute myeloid leukaemia (AML), as ascertained for all inherited BMFS. We already reported four patients with different forms of BMFS/AA with chromosome anomalies as primary etiologic event: the chromosome changes exerted an effect on specific genes, namely RUNX1, MPL, and FLI1, leading to the disease. RESULTS: We report two further patients with non-hereditary BM failure, with diagnosis of severe aplastic anaemia and pancytopenia caused by two different constitutional structural anomalies involving chromosome 8, and possibly leading to the disorder due to effects on the RUNX1T1 gene, which was hypo-expressed and hyper-expressed, respectively, in the two patients. The chromosome change was unbalanced in one patient, and balanced in the other one. CONCLUSIONS: We analyzed the sequence of events in the pathogenesis of the disease in the two patients, including a number of non-haematological signs present in the one with the unbalanced anomaly. We demonstrated that in these two patients the primary event causing BMFS/AA was the constitutional chromosome anomaly. If we take into account the cohort of 219 patients with a similar diagnosis in whom we made cytogenetic studies in the years 2003-2017, we conclude that cytogenetic investigations were instrumental to reach a diagnosis in 52 of them. We postulate that a chromosome change is the primary cause of BMFS/AA in a not negligible proportion of cases, as it was ascertained in 6 of these patients.

13.
Arch Ital Biol ; 144(2): 115-26, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16642790

RESUMEN

The fate of adult-generated neurons in dentate gyrus is mainly determined early, before they receive synapses. In developing brain, classical neurotransmitters such as GABA and glutamate exert trophic effects before synaptogenesis. In order for this to occur in adult brain as well, immature non-contacted cells must express functional receptors to GABA and glutamate. In this investigation, patch-clamp recordings were used in adult rat dentate gyrus slices to assess the presence and analyze the characteristics of GABA- and glutamate-evoked currents in highly immature, synaptically-silent granule cells. Whole-cell patch-clamp recordings showed that all the analyzed cells responded to puff application of GABA and most of them responded to glutamate. Currents evoked by GABA were mediated exclusively by GABAA receptors and those elicited by glutamate were mediated by NMDA and AMPA/Kainate receptors. GABAA receptor-mediated currents were reduced by furosemide, which suggests that synaptically-silent immature neurons express high-affinity, alpha4-subunit-containing GABAA receptors. Gramicidin-perforated-patch recordings showed that GABAA receptor-mediated currents exerted a depolarizing effect due to high intracellular chloride concentration. Synaptically-silent immature cells shared morphological and electrophysiological properties with GFP-expressing, 7-day-old adult-generated granule layer cells, indicating that they could be in the first week of life, the period of maximal newborn cell death. Moreover, the presence of functional GABA and glutamate receptors was confirmed in these GFP-expressing cells. Present findings are mostly consistent with previous data obtained in female mice undergoing spontaneous activity and in transgenic mice, except for some inconsistencies about the presence of functional glutamatergic receptors. We speculate that adult-generated, non-contacted granule cells may be able to sense activity-related variations of GABA and glutamate extracellular levels. This condition is necessary, even if not sufficient, for these neurotransmitters to have a direct role in addressing cell survival.


Asunto(s)
Giro Dentado/metabolismo , Neuronas/metabolismo , Receptores de GABA/metabolismo , Receptores de Glutamato/metabolismo , Células Madre/metabolismo , Sinapsis/metabolismo , Animales , Diferenciación Celular/fisiología , Giro Dentado/citología , Agonistas de Aminoácidos Excitadores/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Agonistas del GABA/farmacología , Antagonistas del GABA/farmacología , Ácido Glutámico/metabolismo , Canales Iónicos/efectos de los fármacos , Canales Iónicos/fisiología , Masculino , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/fisiología , Neuronas/efectos de los fármacos , Técnicas de Cultivo de Órganos , Técnicas de Placa-Clamp , Ratas , Ratas Sprague-Dawley , Receptores de GABA/efectos de los fármacos , Receptores de Glutamato/efectos de los fármacos , Células Madre/efectos de los fármacos , Sinapsis/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/fisiología , Ácido gamma-Aminobutírico/metabolismo
14.
Biochim Biophys Acta ; 827(3): 403-9, 1985 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-2982409

RESUMEN

5'-Nucleotidase from bull seminal plasma is inhibited by dithiothreitol and dithioerythritol. These reactives proved to dissociate the dimeric glycoprotein 5'-nucleotidase of Mr 160 000 into two subunits of apparent Mr 80 000, indicating that the subunits are held together by interchain disulfide bridges. HPLC determinations of cysteic acid and carboxymethylcysteine protein derivatives resulted in 50 +/- 3 half-cystine plus cysteine residues, while 1.9 +/- 0.4 free cysteine residues were estimated by HPLC analysis. The enzyme is inhibited by EDTA and EGTA, and the inhibition appears to be of the non-competitive type for both the chelating agents. Experiments for the enzyme activity recovery by MgCl2 and CaCl2 additions, after the EDTA and EGTA treatments in the presence of 8 M urea, are reported.


Asunto(s)
Quelantes/farmacología , Ditioeritritol/farmacología , Ditiotreitol/análogos & derivados , Ditiotreitol/farmacología , Nucleotidasas/metabolismo , Semen/enzimología , 5'-Nucleotidasa , Animales , Cloruro de Calcio/farmacología , Bovinos , Cromatografía Líquida de Alta Presión , Disulfuros/metabolismo , Ácido Edético/farmacología , Ácido Egtácico/farmacología , Sustancias Macromoleculares , Magnesio/farmacología , Cloruro de Magnesio , Masculino , Peso Molecular
15.
Biochim Biophys Acta ; 1080(3): 252-8, 1991 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-1954233

RESUMEN

Soluble low Km 5'-nucleotidase from human seminal plasma has been purified to homogeneity by one affinity and two gel-filtration chromatographic steps. The pure enzyme had a specific activity of 2000 nmol min-1 mg-1. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of purified low Km 5'-nucleotidase revealed a single polypeptide band of 40 +/- 7 kDa and a tetrameric structure of 160 +/- 10 kDa has been proposed for the native enzyme. The kinetic properties of low Km 5'-nucleotidase have been determined and rather unique characteristics have been found for this soluble low Km 5'-nucleotidase: the substrate efficiency was slightly higher for IMP with an optimum pH at 7.5; the enzyme showed an absolute dependence on Mg2+ ions. Ca2+ could replace Mg2+ ions for activity while other divalent cations could not substitute for Mg2+; the enzymes were equally activated by ATP and ADP up to 0.1 mM concentrations. At higher concentrations up to 1 mM, ADP was still an activator while ATP caused a gradual decrease of activation to the native activity. This effect could not be related to the Mg-ATP = complexes since the enzymic preparation Mg(2+)-free still showed the same biphasic pattern of activation.


Asunto(s)
5'-Nucleotidasa/aislamiento & purificación , Semen/enzimología , 5'-Nucleotidasa/química , 5'-Nucleotidasa/metabolismo , Adenosina Difosfato/farmacología , Adenosina Trifosfato/farmacología , Humanos , Concentración de Iones de Hidrógeno , Cinética , Metales/farmacología , Peso Molecular , Especificidad por Sustrato
16.
Prostate Cancer Prostatic Dis ; 8(4): 344-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16130012

RESUMEN

Prostasomes, prostatic secretory vesicles found in human ejaculates, were analyzed to verify the existence at their surfaces of enzymes involved in the degradation of the extracellular matrix. Findings were compared with those of prostasomes isolated from two human adenocarcinoma cell lines that reflect clinical features and molecular pathways of androgen-insensitive and hormone-responsive prostate cancer. Our aim was to determine whether neoplastic transformation is accompanied by changes of glycosidase and protease activities. Our results show that decreases of dipeptidyl peptidase IV and increases of urokinase plasminogen activator and cathepsin B are consistent with the clinical features of the cell lines, whereas increases of glycosidase activities seem to be of scarce biological significance.


Asunto(s)
Matriz Extracelular/metabolismo , Vesículas Secretoras/enzimología , Semen/citología , Semen/enzimología , Catepsina B/metabolismo , Línea Celular Tumoral , Dipeptidil Peptidasa 4/metabolismo , Glicósido Hidrolasas/metabolismo , Humanos , Masculino , Péptido Hidrolasas/metabolismo , Peptidoglicano/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
17.
Leukemia ; 15(6): 971-5, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11417485

RESUMEN

Trisomic cells in neoplasms may represent abnormal clones originated from a tissue-confined mosaicism, and arise therefore by a meiotic error. We report on a 16-month-old child with erythroleukaemia (AML-M6), whose marrow karyotype at onset was 48,XX,del(13)(q12q14),del(14)(q22q32),+21,+21. The parental origin of the supernumerary chromosomes 21 was investigated by comparing 10 polymorphic loci scattered along the whole chromosome on the patient's marrow and her parents' leukocytes. Three loci were informative for the presence of three alleles, two of which were of maternal origin; two further loci showed a maternal allele of higher intensity. Lymphocytes and skin fibroblasts showed a normal karyotype, and molecular analysis on leukocytes at remission, buccal smear and urinary sediment cells consistently showed only one maternal allele, whereas neonatal blood from Guthrie spot showed two maternal alleles as in the marrow. An accurate clinical re-evaluation confirmed a normal phenotype. Our results indicate that tetrasomy 21 arose from a marrow clone with trisomy 21 of meiotic origin. To the best of our knowledge, this is the first evidence that supernumerary chromosomes in neoplastic clones may in fact be present due to a meiotic error. This demonstrates that a tissue-confined constitutional mosaicism for a trisomy may indeed represent the first event in multistep carcinogenesis.


Asunto(s)
Cromosomas Humanos Par 21 , Leucemia Eritroblástica Aguda/genética , Meiosis , Mosaicismo/genética , Trisomía , Alelos , Aneuploidia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Médula Ósea/patología , Trasplante de Médula Ósea , Preescolar , Células Clonales/patología , Terapia Combinada , Dermatoglifia , Síndrome de Down/genética , Femenino , Sangre Fetal/química , Sangre Fetal/citología , Estudios de Seguimiento , Humanos , Hibridación Fluorescente in Situ , Interfase , Cariotipificación , Leucemia Eritroblástica Aguda/tratamiento farmacológico , Leucemia Eritroblástica Aguda/terapia , Repeticiones de Microsatélite , Modelos Genéticos , No Disyunción Genética
18.
Sci Rep ; 5: 9471, 2015 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-25804527

RESUMEN

The 3ß-hydroxysterol Δ14-reductase, encoded by the Tm7sf2 gene, is an enzyme involved in cholesterol biosynthesis. Cholesterol and its derivatives control epidermal barrier integrity and are protective against environmental insults. To determine the role of the gene in skin cholesterol homeostasis, we applied 12-o-tetradecanoylphorbol-13-acetate (TPA) to the skin of Tm7sf2(+/+) and Tm7sf2(-/-) mice. TPA increased skin cholesterol levels by inducing de novo synthesis and up-take only in Tm7sf2(+/+) mouse, confirming that the gene maintains cholesterol homeostasis under stress conditions. Cholesterol sulfate, one of the major players in skin permeability, was doubled by TPA treatment in the skin of wild-type animals but this response was lost in Tm7sf2(-/-) mice. The expression of markers of epidermal differentiation concomitant with farnesoid-X-receptor and p38 MAPK activation were also disrupted in Tm7sf2(-/-) mice. We then subjected Tm7sf2(+/+) and Tm7sf2(-/-) mice to a classical two-stage skin carcinogenesis protocol. We found that the loss of Tm7sf2 increased incidence and multiplicity of skin papillomas. Interestingly, the null genotype showed reduced expression of nur77, a gene associated with resistance to neoplastic transformation. In conclusion, the loss of Tm7sf2 alters the expression of proteins involved in epidermal differentiation by reducing the levels of cholesterol sulfate.


Asunto(s)
Colesterol/biosíntesis , Oxidorreductasas/metabolismo , Neoplasias Cutáneas/genética , Piel/metabolismo , Animales , Carcinógenos , Diferenciación Celular/genética , Transformación Celular Neoplásica/genética , Colesterol/genética , Humanos , Ratones , Ratones Transgénicos , Oxidorreductasas/genética , Papiloma/patología , Papiloma/virología , Piel/patología , Piel/virología , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología
19.
Transl Psychiatry ; 5: e687, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26624926

RESUMEN

Several studies have demonstrated that allelic variants related to inflammation and the immune system may increase the risk for major depressive disorder (MDD) and reduce patient responsiveness to antidepressant treatment. Proteasomes are fundamental complexes that contribute to the regulation of T-cell function. Only one study has shown a putative role of proteasomal PSMA7, PSMD9 and PSMD13 genes in the susceptibility to an antidepressant response, and sparse data are available regarding the potential alterations in proteasome expression in psychiatric disorders such as MDD. The aim of this study was to clarify the role of these genes in the mechanisms underlying the response/resistance to MDD treatment. We performed a case-control association study on 621 MDD patients, of whom 390 were classified as treatment-resistant depression (TRD), and we collected peripheral blood cells and fibroblasts for mRNA expression analyses. The analyses showed that subjects carrying the homozygous GG genotype of PSMD13 rs3817629 had a twofold greater risk of developing TRD and exhibited a lower PSMD13 mRNA level in fibroblasts than subjects carrying the A allele. In addition, we found a positive association between PSMD9 rs1043307 and the presence of anxiety disorders in comorbidity with MDD, although this result was not significant following correction for multiple comparisons. In conclusion, by confirming the involvement of PSMD13 in the MDD treatment response, our data corroborate the hypothesis that the dysregulation of the complex responsible for the degradation of intracellular proteins and potentially controlling autoimmunity- and immune tolerance-related processes may be involved in several phenotypes, including the TRD.


Asunto(s)
Trastorno Depresivo Mayor/genética , Trastorno Depresivo Resistente al Tratamiento/genética , Complejo de la Endopetidasa Proteasomal/genética , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
Radiat Prot Dosimetry ; 166(1-4): 95-100, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25870433

RESUMEN

Shwachman-Diamond syndrome is an autosomal-recessive disorder characterised by bone marrow failure and a cumulative risk of progression to acute myeloid leukaemia. The Shwachman-Bodian-Diamond syndrome (SBDS) gene, the only gene known to be causative of the pathology, is involved in ribosomal biogenesis, stress responses and DNA repair, and the lack of SBDS sensitises cells to many stressors and leads to mitotic spindle destabilisation. The effect of ionising radiation on SBDS-deficient cells was investigated using immortalised lymphocytes from SDS patients in comparison with positive and negative controls in order to test whether, in response to ionising radiation exposure, any impairment in the DNA repair machinery could be observed. After irradiating cells with different doses of X-rays or gamma-rays, DNA repair kinetics and the residual damages using the alkaline COMET assay and the γ-H2AX assay were assessed, respectively. In this work, preliminary data about the comparison between ionising radiation effects in different patients-derived cells and healthy control cells are presented.


Asunto(s)
Enfermedades de la Médula Ósea/genética , Enfermedades de la Médula Ósea/radioterapia , Daño del ADN/efectos de la radiación , Reparación del ADN/efectos de la radiación , Insuficiencia Pancreática Exocrina/genética , Insuficiencia Pancreática Exocrina/radioterapia , Lipomatosis/genética , Lipomatosis/radioterapia , Linfocitos/efectos de la radiación , Tolerancia a Radiación/genética , Ensayo Cometa , Rayos gamma , Histonas/genética , Humanos , Cinética , Proteínas/genética , Proteínas/metabolismo , Síndrome de Shwachman-Diamond , Rayos X
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