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1.
J Vet Pharmacol Ther ; 40(1): 70-76, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27345291

RESUMEN

The effects of a selective bradykinin 1 receptor antagonist, compound A, were evaluated in a canine model of acute inflammatory model of arthritis. Despite detection of the B1 receptor in canine type B synoviocytes using a fluorescent ligand, oral administration of compound A (9 and 27 mg/kg) did not improve weight bearing of dogs injected intra-articularly with IL-1ß in a force plate analysis. Analysis of the synovial fluid of IL-1ß-treated dogs indicated high levels of bradykinin postchallenge. Excellent exposure, coupled with evidence of the presence of the B1 receptor during an acute inflammatory model of pain, indicates an inability of the receptor to mediate inflammatory pain in canines.


Asunto(s)
Artritis/veterinaria , Antagonistas del Receptor de Bradiquinina B1/uso terapéutico , Enfermedades de los Perros/tratamiento farmacológico , Niacinamida/farmacología , Animales , Artritis/tratamiento farmacológico , Células Cultivadas , Modelos Animales de Enfermedad , Perros , Masculino , Niacinamida/análisis , Receptor de Bradiquinina B1/análisis , Sinoviocitos/química
2.
Prog Urol ; 25(5): 282-7, 2015 Apr.
Artículo en Francés | MEDLINE | ID: mdl-25724863

RESUMEN

INTRODUCTION AND OBJECTIVE: The objective of this study was to assess the oncological results of a population of patients which undergo surveillance after diagnosis of stage I testicular seminoma (2, 5 and 8 years overall, specific and recurrence free survival). We also research recurrence risk factors. PATIENTS AND METHODS: We have looked at the data of all patients treated in our center since 1993 for a grade I testicular seminoma. We focused on age at diagnosis, biological (tumoral markers) and pathological (tumor size, rete testis, lymphovascular, tunica albuginea or spermatic cord invasion) data. During surveillance, we noted the number, the localization and the interval until recurrence and death. We calculated 2, 5 and 8 years overall, specific and recurrence-free survival and searched recurrence risk factors. RESULTS: Sixty-nine patients (mean age: 37) were followed during a mean time of 97 months. Sixty-three per cent of the tumours were less than 4 cm (50 lesions). Lymphovascular, rete testis, spermatic cord and tunica albuginea invasion were present in respectively 21%, 33%, 4% and 29% of the cases. LDH and HCG were above normal rate in respectively 44 and 27% of the cases. Eighteen patients (23%) relapsed at a mean time of 12 months. Recurrence-free survival was respectively 81%, 77% and 77% at 2, 5 and 8 years. Tumor size<4 cm (P = 0.002), rete testis invasion (P = 0.03) and stage ≥ pT2 (P = 0.012) were associated with recurrence in univariate analysis. Using multivariate analysis, only tumor size >4 cm was a recurrence risk factor (risk multiplied by 3). At the end of the study, 77 patients are alive (97.5%). Overall and specific survival was 97.5% at 2, 5 and 8 years. CONCLUSION: We show here the interest of surveillance in case of stage 1 testicular seminoma. The overall and specific survivals are the same as after chemotherapy or radiotherapy. Furthermore, we confirm the role of tumor size to stratify recurrence risk.


Asunto(s)
Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/terapia , Seminoma/diagnóstico , Seminoma/terapia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/terapia , Adulto , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Estudios de Seguimiento , Francia , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , Orquiectomía/métodos , Vigilancia de la Población , Radioterapia Adyuvante , Estudios Retrospectivos , Factores de Riesgo , Seminoma/mortalidad , Seminoma/patología , Neoplasias Testiculares/mortalidad , Neoplasias Testiculares/patología , Resultado del Tratamiento
3.
Ann Oncol ; 23(8): 1943-1953, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22689175

RESUMEN

The administration of mammalian target of rapamycin (mTOR) inhibitors can give rise to a potentially life-threatening adverse event, often referred to as 'non-infectious pneumonitis' (NIP), which is characterized by non-infectious, non-malignant, and non-specific inflammatory infiltrates. Patients usually present with cough and/or dyspnoea. We provide a brief description of the mechanism of action of mTOR inhibitors and their overall safety in patients with metastatic renal cell carcinoma (mRCC) and review the literature on mTOR inhibitor-associated NIP in patients with solid tumours. The review was used to derive questions on the diagnosis, management, and monitoring of mRCC patients with NIP, and to develop a decision tree for use in routine clinical practise. A key recommendation was the subdivision of grade 2 NIP into grades 2a and 2b, where grade 2a is closer to grade 1 and grade 2b to grade 3. This subdivision is important because it takes into account the nature and severity of clinical symptoms potentially related to NIP, either the onset of new symptoms or the worsening of existing symptoms, and thus determines the type and frequency of follow-up. It also helps to identify a subgroup of patients in whom treatment, if effective, may be continued without dose adjustment.


Asunto(s)
Antibióticos Antineoplásicos/efectos adversos , Carcinoma de Células Renales/tratamiento farmacológico , Neoplasias Renales/tratamiento farmacológico , Neumonía/inducido químicamente , Neumonía/terapia , Inhibidores de Proteínas Quinasas/efectos adversos , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Humanos , Incidencia , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Metástasis de la Neoplasia , Neumonía/diagnóstico , Neumonía/epidemiología , Serina-Treonina Quinasas TOR/metabolismo
4.
Am J Gastroenterol ; 106(4): 771-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21386832

RESUMEN

OBJECTIVES: Rescue therapy with either cyclosporine (CYS) or infliximab (IFX) is an effective option in patients with intravenous steroid-refractory attacks of ulcerative colitis (UC). In patients who fail, colectomy is usually recommended, but a second-line rescue therapy with IFX or CYS is an alternative. The aims of this study were to investigate the efficacy and tolerance of IFX and CYS as a second-line rescue therapy in steroid-refractory UC or indeterminate colitis (IC) unsuccessfully treated with CYS or IFX. METHODS: This was a retrospective survey of patients seen during the period 2000-2008 in the GETAID centers. Inclusion criteria included a delay of <1 month between CYS withdrawal (when used first) and IFX, or a delay of <2 months between IFX (when used first) and CYS, and a follow-up of at least 3 months after inclusion. Time-to-colectomy, clinical response, and occurrence of serious adverse events were analyzed. RESULTS: A total of 86 patients (median age 34 years; 49 males; 71 UC and 15 IC) were successively treated with CYS and IFX. The median (± s.e.) follow-up time was 22.6 (7.0) months. During the study period, 49 patients failed to respond to the second-line rescue therapy and underwent a colectomy. The probability of colectomy-free survival (± s.e.) was 61.3 ± 5.3% at 3 months and 41.3 ± 5.6 % at 12 months. A case of fatal pulmonary embolism occurred at 1 day after surgery in a 45-year-old man. Also, nine infectious complications were observed during the second-line rescue therapy. CONCLUSIONS: In patients with intravenous steroid-refractory UC and who fail to respond to CYS or IFX, a second-line rescue therapy may be effective in carefully selected patients, avoiding colectomy within 2 months in two-thirds of them. The risk/benefit ratio should still be considered individually.


Asunto(s)
Antiinflamatorios/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Colitis Ulcerosa/tratamiento farmacológico , Ciclosporina/administración & dosificación , Resistencia a Medicamentos , Terapia Recuperativa/métodos , Esteroides/administración & dosificación , Administración Oral , Adolescente , Adulto , Antiinflamatorios/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Niño , Colectomía , Colitis Ulcerosa/cirugía , Ciclosporina/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Infecciones/inducido químicamente , Infliximab , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Embolia Pulmonar/inducido químicamente , Embolia Pulmonar/mortalidad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
5.
Prog Urol ; 21 Suppl 2: S27-33, 2011 Mar.
Artículo en Francés | MEDLINE | ID: mdl-21397824

RESUMEN

Three clinical cases have shown the superiority of sunitinib in first line therapy intermediate risk metastatic clear cell renal carcinoma and a best safety of bevacizumab plus interferon, the current lack of high level of evidence arguments for the neo-adjuvant treatment of kidney cancer, the importance to prevent mucositis during a mTOR inhibitors treatment and the diagnostic pitfalls of its pulmonary complications.


Asunto(s)
Carcinoma de Células Renales/terapia , Neoplasias Renales/terapia , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/cirugía , Femenino , Humanos , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/cirugía , Masculino , Persona de Mediana Edad
6.
Prog Urol ; 20 Suppl 1: S27-32, 2010 Mar.
Artículo en Francés | MEDLINE | ID: mdl-20493440

RESUMEN

Direct side effects of the inhibition of activation of VEGF receptors are well known and could be easily explained (HTA). The indirect toxicity of the inhibitors of tyrosinekinases is much less known and several hypotheses appear. Usually, the common side effects of the inhibitors of tyrosine-kinases can be easily managed and are reversible when the treatment is stopped. Their management is essentially based on prevention measures. It is necessary to stop definitively or temporarily the treatment in case of intensification of pre-existing comorbidities or side effects of rank 3 or 4. There is no predictive factor of treatment toxicity and, at the moment, there is thus no indication in a previous dose adaptation.


Asunto(s)
Inhibidores de la Angiogénesis/efectos adversos , Carcinoma de Células Renales/tratamiento farmacológico , Neoplasias Renales/tratamiento farmacológico , Anciano , Inhibidores de la Angiogénesis/uso terapéutico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/terapia , Humanos , Masculino
8.
Gut ; 56(12): 1688-95, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17595234

RESUMEN

AIMS: The CDX1 and CDX2 homeoproteins are intestine-specific transcription factors regulating homeostasis. We investigated their relevance in experimentally-induced intestinal inflammation. METHODS: The response to intestinal inflammation induced by dextran sodium sulfate (DSS) was compared in wild type, Cdx1(-/-) and Cdx2(+/-) mice. Intestinal permeability was determined in wild type and Cdx2(+/-) mice. Protein-protein interactions were investigated by co-immunoprecipitation and GST-pulldown, and their functional consequences were assessed using Luciferase reporter systems. RESULTS: Heterozygous Cdx2(+/-) mice, but not Cdx1(-/-) mice, were hypersensitive to DSS-induced acute inflammation as all these mice showed blood in the stools at day 1 of DSS treatment. Hypersensitivity was associated to a 50% higher intestinal permeability. In Cdx2(+/-) mice, the colonic epithelium was repaired during the week after the end of DSS treatment, whereas two weeks were required for wild type animals. Subsequently, no colonic tumour was observed in Cdx2(+/-) mice subjected to 5 repeated cycles of DSS, in contrast to the 2.7 tumours found per wild type mouse. Based on the fact that Smad3(+/-) mice, like Cdx2(+/-) mice, better repair the damaged intestinal epithelium, we found that the CDX2 protein interacts with SMAD3, independently of SMAD4, resulting in a 5-fold stimulation of SMAD3 transcriptional activity. CDX1 also interacted with SMAD3 but it inhibited by 10-fold the SMAD3/SMAD4-dependent transcription. CONCLUSION: The Cdx1 and Cdx2 homeobox genes have distinct effects on the outcome of a pro-inflammatory challenge. This is mirrored by different functional interactions of the CDX1 and CDX2 proteins with SMAD3, a major element of the TGFbeta signalling pathway.


Asunto(s)
Colitis Ulcerosa/genética , Genes Homeobox , Proteínas de Homeodominio/genética , Factores de Transcripción/genética , Animales , Factor de Transcripción CDX2 , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/patología , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/genética , Sulfato de Dextran , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad , Proteínas de Homeodominio/metabolismo , Absorción Intestinal/efectos de los fármacos , Absorción Intestinal/genética , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Permeabilidad/efectos de los fármacos , Índice de Severidad de la Enfermedad , Proteína smad3/metabolismo , Factores de Transcripción/metabolismo
9.
Aliment Pharmacol Ther ; 47(5): 588-595, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29315694

RESUMEN

BACKGROUND: Long-term outcome of ustekinumab in Crohn's disease (CD) has not been evaluated. AIM: To evaluate the long-term efficacy and safety of ustekinumab and identify the predictive factors of ustekinumab failure-free persistence in a cohort of anti-TNF refractory CD patients. METHODS: We performed a retrospective multicentre cohort study including all consecutive CD patients who began subcutaneous ustekinumab and presented a clinical response (defined as a significant improvement of CD-related clinical symptoms assessed by the patient's physician leading to continued ustekinumab) during the first year of treatment. Primary outcome was treatment failure defined as withdrawal of treatment due to loss of response, intolerance or need for surgery. RESULTS: Eighty-eight of the 122 (72%) CD patients beginning ustekinumab from March 2011 to December 2014, responded to ustekinumab and were followed up until November 2016. Median time on ustekinumab was 26.6 (13.4-34.4) months. Forty-seven patients (54%) continued ustekinumab with a clinical response and 38 (43%) stopped treatment (32 for failure, five for remission and one for pregnancy). Endoscopic response was observed in 82% of patients with endoscopic evaluation and mucosal healing in 39%. Ustekinumab failure-free persistence rates were 78% at 12 months, 66% at 24 months and 55% at 36 months. No predictive factor of ustekinumab failure-free persistence was identified. One severe adverse event was observed (anal adenocarcinoma). CONCLUSION: In this cohort of refractory CD patients receiving long-term ustekinumab therapy, more than 50% of patients continued ustekinumab treatment with no loss of response, intolerance or surgery and with a good safety profile.


Asunto(s)
Enfermedad de Crohn/tratamiento farmacológico , Ustekinumab/administración & dosificación , Ustekinumab/efectos adversos , Adulto , Estudios de Cohortes , Enfermedad de Crohn/epidemiología , Resistencia a Medicamentos/efectos de los fármacos , Endoscopía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Embarazo , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/uso terapéutico
10.
Eur J Cancer ; 42(1): 50-4, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16330205

RESUMEN

EORTC protocol 30924 is an international randomized trial reporting a 7.3 year update of a 2 weekly regimen of high-dose intensity chemotherapy with M-VAC plus granulocyte colony stimulating factor (HD-M-VAC) compared to classic M-VAC in advanced transitional cell carcinoma (TCC). Two hundred and sixty three untreated patients with bidimensionally measurable TCC were included. In an intention to treat analysis, there were 28 complete responses (CR) (21%) and 55 partial responses (PR) (41%), for an overall response rate (RR) of 64% on the HD-M-VAC arm. On M-VAC, there were 12 CR (9%) and 53 PR (41%), for an overall RR of 50% . The P-value for the difference in CR was 0.009; and for RR, was 0.06. After a median follow-up of 7.3 years, 24.6% are alive on the HD-M-VAC arm vs. 13.2% on the M-VAC arm. Median progression-free survival was better with HD-MVAC (9.5 months) vs. M-VAC (8.1 months). The mortality hazard ratio (HR) was 0.76. The 2-year survival rate for HD-M-VAC was 36.7% vs. 26.2% for M-VAC. At 5 years, the survival rate was 21.8% in the HD-M-VAC vs. 13.5%. Median survival was 15.1 months on HD-MVAC and 14.9 months on M-VAC. There was one death from toxicity in each arm; and more patients died to malignant disease in the M-VAC arm (76%) than in the HD-M-VAC arm (64.9%). With longer follow-up initial results have been confirmed, and shows that HD-M-VAC produces a borderline statistically significant relative reduction in the risk of progression and death compared to M-VAC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Transicionales/tratamiento farmacológico , Neoplasias Urológicas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Cisplatino/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Humanos , Masculino , Metotrexato/administración & dosificación , Persona de Mediana Edad , Análisis de Supervivencia , Vinblastina/administración & dosificación
11.
Gynecol Obstet Fertil ; 34(1): 34-7, 2006 Jan.
Artículo en Francés | MEDLINE | ID: mdl-16406736

RESUMEN

Fetal goiter is a rare occurrence of which neonatal consequences are not always predictable. Concerning three cases of goiters associated with hypothyroidism discovered in utero, the authors describe the way to take care of in this bad codified situation. They insist upon the major role of ultrasound for goiter diagnosis and its impacts and for control of treatment efficiency. They also discuss intra amniotic L-Thyroxine injection and insist upon the necessity to obtain quick and definite thyroid evaluation after birth before decision to abstain from neonatal therapy.


Asunto(s)
Hipotiroidismo Congénito/diagnóstico , Enfermedades Fetales/diagnóstico , Bocio/diagnóstico , Bocio/tratamiento farmacológico , Tiroxina/uso terapéutico , Adulto , Hipotiroidismo Congénito/tratamiento farmacológico , Femenino , Enfermedades Fetales/tratamiento farmacológico , Humanos , Embarazo , Resultado del Embarazo , Pruebas de Función de la Tiroides , Resultado del Tratamiento , Ultrasonografía Prenatal
12.
J Mol Biol ; 187(2): 305-8, 1986 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-3517353

RESUMEN

The analysis of protein phosphorylation in the bacterium Escherichia coli showed that, while most phosphoproteins are modified at serine and/or threonine residues, one of them is modified exclusively at tyrosine. This particular protein which has a molecular weight of 54,500 and a pHi value of 5.6 is found associated with the membrane/ribosome fraction of the cell.


Asunto(s)
Proteínas Bacterianas/metabolismo , Escherichia coli/metabolismo , Fosfoproteínas/metabolismo , Tirosina , Secuencia de Aminoácidos , Autorradiografía , Electroforesis en Gel de Poliacrilamida , Focalización Isoeléctrica , Fosforilación
13.
J Mol Biol ; 259(5): 891-5, 1996 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-8683591

RESUMEN

Autophosphorylation at tyrosine is a common process in eukaryotic kinases, which is generally modulated by regulatory ligands and affects the properties of these enzymes. We report that this type of modification occurs also in bacteria, namely in an 81 kDa protein from Acinetobacter johnsonii. This protein is phosphorylated at the expense of ATP exclusively at tyrosine residues. It is located in the inner-membrane fraction of cells and can be totally solubilized by detergents. It has been purified to homogeneity by antiphosphotyrosine immunochromatography. Analysis of the peptides released under trypsin proteolysis of the protein has shown that it autophosphorylates at several tyrosine residues. The discovery of protein autophosphorylation in bacteria seems of special interest for studying the regulatory aspects of this modification when considering the relative simplicity of the bacterial systems, as compared with most eukaryotic systems, namely in terms of physiology and genetics.


Asunto(s)
Acinetobacter/metabolismo , Proteínas Bacterianas/metabolismo , Tirosina/metabolismo , Adenosina Trifosfato/metabolismo , Proteínas Bacterianas/aislamiento & purificación , Sitios de Unión , Fosforilación
14.
J Mol Biol ; 304(3): 311-21, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11090276

RESUMEN

The phosphorylation of proteins at tyrosine residues is known to play a key role in the control of numerous fundamental processes in animal systems. In contrast, the biological significance of protein-tyrosine phosphorylation in bacteria, which has only been recognised recently, is still unclear. Here, we have analysed the role in Escherichia coli cells of an autophosphorylating protein-tyrosine kinase, Wzc, and a phosphotyrosine-protein phosphatase, Wzb, by performing knock-out experiments on the corresponding genes, wzc and wzb, and looking at the metabolic consequences induced. The results demonstrate that the phosphorylation of Wzc, as regulated by Wzb, is directly connected with the production of a particular capsular polysaccharide, colanic acid. Thus, when Wzc is phosphorylated on tyrosine, no colanic acid is synthesised by bacteria, but when dephosphorylated by Wzb, colanic acid is produced. This process is rather specific to the pair of proteins Wzc/Wzb. Indeed, a much lesser effect, if any, on colanic acid synthesis is observed when knock-out experiments are performed on another pair of genes, etk and etp, which also encode respectively a protein-tyrosine kinase, Etk, and a phosphotyrosine-protein phosphatase, Etp, in E. coli. In addition, the analysis of the phosphorylation reaction at the molecular level reveals differences between Gram-negative and Gram-positive bacteria, namely in the number of protein components required for this reaction to occur.


Asunto(s)
Proteínas Bacterianas , Bacterias Gramnegativas/metabolismo , Proteínas de la Membrana , Fosfotirosina/metabolismo , Polisacáridos/biosíntesis , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Secuencia de Aminoácidos , Proteínas de Escherichia coli , Eliminación de Gen , Bacterias Gramnegativas/enzimología , Bacterias Gramnegativas/genética , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/enzimología , Bacterias Grampositivas/genética , Bacterias Grampositivas/metabolismo , Datos de Secuencia Molecular , Fosforilación , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Quinasas/química , Proteínas Tirosina Quinasas/genética , Alineación de Secuencia , Especificidad por Sustrato
15.
J Mol Biol ; 278(2): 339-47, 1998 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-9571056

RESUMEN

The ptp gene of Acinetobacter johnsonii was previously reported to encode a low-molecular-mass protein, Ptp, whose amino acid sequence, predicted from the theoretical analysis of the nucleotide sequence of the gene, exhibits a high degree of similarity with those of different eukaryotic and prokaryotic phosphotyrosine-protein phophatases. We have now overexpressed the ptp gene in Escherichia coli cells, purified the Ptp protein to homogeneity by a single-step chromatographic procedure, and analysed its functional properties. We have shown that Ptp can catalyse the dephosphorylation of p-nitrophenyl phosphate and phosphotyrosine, but has no effect on phosphoserine or phosphothreonine. Its activity is blocked by ammonium molybdate and sodium orthovanadate, which are strong inhibitors of phosphotyrosine-protein phosphatases, as well as by N-ethylmaleimide and iodoacetic acid. Such specificity of Ptp for phosphotyrosine has been confirmed by the observation that it can dephosphorylate endogenous proteins phosphorylated on tyrosine, but not proteins modified on either serine or threonine. In addition, Ptp has been shown to quantitatively dephosphorylate two exogenous peptides, derived respectively from leech hirudin and human gastrin, previously phosphorylated on tyrosine. Moreover, site-directed mutagenesis experiments performed on Cys11 and Arg16, which are both present in the sequence motif (H/V)C(X5)R(S/T) typical of eukaryotic phosphotyrosine-protein phosphatases, have demonstrated that each amino acid residue is essential for the catalytic activity of Ptp. Taken together, these data provide evidence that Ptp is a member of the phosphotyrosine-protein phosphatase family. Furthermore, in search for the biological function of Ptp, we have found that it can specifically dephosphorylate an endogenous protein kinase, termed Ptk, which is known to autophosphorylate at multiple tyrosine residues in the inner membrane of Acinetobacter johnsonii cells. This represents the first identification of a protein substrate for a bacterial phosphotyrosine-protein phosphatase, and therefore constitutes a possible model for analysing the role of reversible phosphorylation on tyrosine in the regulation of microbial physiology.


Asunto(s)
Acinetobacter/enzimología , Proteínas Tirosina Fosfatasas/metabolismo , Secuencia de Aminoácidos , Datos de Secuencia Molecular , Peso Molecular , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas/aislamiento & purificación , Homología de Secuencia de Aminoácido , Especificidad por Sustrato
16.
Aliment Pharmacol Ther ; 21(4): 445-54, 2005 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-15709996

RESUMEN

BACKGROUND: The most frequently used intravenous lipid emulsions are composed of 100% long chain triacylglycerols from soybean oil or of 50% long chain triacylglycerols-50% medium chain triacylglycerols. A newer emulsion, ClinOleic 20% containing 80% olive oil and 20% soybean oil, was suggested to reduce lipid peroxidation and immune function impairment. AIM: To assess ClinOleic 20%'s efficacy, safety and effect upon systemic inflammatory parameters in adults on home parenteral nutrition. METHODS: In stable home parenteral nutrition patients, the initial intravenous lipid emulsion was changed for ClinOleic 20%. Nutritional status, clinical and biological tolerance, and systemic inflammatory markers were analysed before and after 1 and 3 months of home parenteral nutrition, with ClinOleic 20% as intravenous lipid emulsion. RESULTS: Clinical and biological nutritional markers and inflammatory parameters did not differ between day 0 and month +3. There was no essential fatty acids deficiency. No side-effects were reported. Three of five patients presenting with migraine during home parenteral nutrition infusion at day 0 felt consistently better at month +3. CONCLUSIONS: ClinOleic 20% is safe and efficient in adult home parenteral nutrition. It maintains normal essential fatty acids status and did not influence inflammatory parameters. In contrast to studies in preterm infants or paediatric patients, no effect on vitamin E concentration or lipid peroxidation was observed.


Asunto(s)
Emulsiones Grasas Intravenosas/uso terapéutico , Nutrición Parenteral en el Domicilio/métodos , Aceites de Plantas/uso terapéutico , Adulto , Anciano , Enfermedad Crónica , Enteritis/terapia , Emulsiones Grasas Intravenosas/efectos adversos , Femenino , Humanos , Mediadores de Inflamación/sangre , Obstrucción Intestinal/terapia , Lípidos/sangre , Masculino , Persona de Mediana Edad , Aceite de Oliva , Nutrición Parenteral en el Domicilio/efectos adversos , Aceites de Plantas/efectos adversos , Traumatismos por Radiación/terapia , Síndrome del Intestino Corto/terapia , Resultado del Tratamiento , Vitaminas/sangre
17.
Dig Liver Dis ; 37(6): 424-31, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15893281

RESUMEN

BACKGROUND: Recent attention focused on the effect of inflammatory cytokines on intermediary metabolism contributing to the nutritional disturbances observed in acute or chronic inflammatory diseases. AIMS: To examine the interactions between immune activation and nutritional parameters in adult Crohn's disease patients. PATIENTS AND METHODS: We analysed anthropometric and biochemical nutritional parameters in 40 Crohn's disease patients and 26 healthy controls, and related them to inflammatory and immune markers. RESULTS: Weight, body mass index, mid-arm circumference, triceps skinfold thickness, as well as albumin, transthyretin, retinol binding protein, insulin growth factor-I and Vitamin A were significantly decreased in Crohn's disease patients and negatively correlated to disease activity. By contrast, erythrocyte sedimentation rate, fibrinogen, C-reactive protein, alpha1-acylglycoprotein, soluble receptor of interleukin-2, blood neopterin, tumour necrosis factor-alpha and interleukin-1beta concentrations were significantly higher in patients and positively correlated to disease activity. Nutritional parameters and acute phase reactants were linked to tumour necrosis factor-alpha and interleukin-1beta concentrations, and markers of nutritional status were negatively correlated to positive acute phase reactants. CONCLUSIONS: In Crohn's disease, inflammatory cytokines appear partly responsible for decreased nutritional status. Thus, nutritional intervention to correct nutritional (in particular protein) depletion, and/or therapeutic intervention reducing inflammation and therefore restoring adequate nutritional proteins synthesis, appears a major therapeutic goal in active Crohn's disease.


Asunto(s)
Enfermedad de Crohn/sangre , Enfermedad de Crohn/inmunología , Estado Nutricional , Adulto , Biomarcadores/sangre , Proteínas Sanguíneas/análisis , Sedimentación Sanguínea , Índice de Masa Corporal , Peso Corporal/fisiología , Estudios de Casos y Controles , Femenino , Humanos , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Interleucina-1/sangre , Masculino , Análisis Multivariante , Neopterin/sangre , Receptores de Interleucina-2/sangre , Solubilidad , Vitamina A/sangre
18.
Leukemia ; 11(12): 2188-91, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9447839

RESUMEN

We report seven patients with both myelodysplastic syndrome (MDS) and inflammatory bowel disease (IBD): Crohn's disease in six cases, ulcerative colitis in one case. We describe their characteristics, and those of 10 previously published similar cases are presented here. Median age at diagnosis of IBD (61 years) was high, as compared to the usual age at diagnosis of IBD. IBD was diagnosed first in nine cases, MDS first in one patient, and both diseases were diagnosed simultaneously in seven cases. Concerning IBD, there was a strong predominance of Crohn's disease (15/17 cases), with an unusually high frequency of colonic involvement (11/15 cases). MDS, in 12/17 cases, showed no excess of marrow blasts. Cytogenetic analysis was abnormal in five of the 13 evaluable cases. These observations suggest that the association between MDS and IBD may not be fortuitous in some cases, and that, in particular, patients with IBD and anemia of nonobvious origin should be evaluated for MDS. The pathogenesis of those associations, however, remains unclear.


Asunto(s)
Enfermedades Inflamatorias del Intestino/complicaciones , Síndromes Mielodisplásicos/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
Gene ; 204(1-2): 259-65, 1997 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-9434192

RESUMEN

Acinetobacter johnsonii harbors a protein tyrosine kinase activity that is able to catalyze autophosphorylation, like a number of eukaryotic tyrosine kinases. A biochemical and genetic analysis of this enzyme was performed. Maximum phosphorylation in vitro was obtained by incubating the kinase for 2 min at pH 7.0 in the presence of 5 mM magnesium chloride. In contrast to eukaryotic enzymes, no inhibitory effect of genistein and no phosphorylation of synthetic substrates such as poly (Glu80 Tyr20) or angiotensin II were observed. The analysis of the bacterial kinase by two-dimensional gel electrophoresis revealed the presence of at least five isoforms, all phosphorylated exclusively at tyrosine, which supports the concept that autophosphorylation occurs at multiple sites within the protein. The cloning and nucleotide sequencing of the gene encoding this kinase were achieved, which represents the first molecular characterization of a gene of this type in bacteria. An open reading frame of 2199 nucleotides encoding a protein of 82,373 Da was detected. The analysis of the deduced amino acid sequence suggested a possible involvement of the enzyme in cell recognition and bacterial pathogenicity. In addition, the cloning and sequencing of the region immediately upstream of the gene encoding the kinase revealed a novel open reading frame of 426 nucleotides encoding a phosphotyrosine protein phosphatase of 16,217 Da, which indicates that autophosphorylation on tyrosine is a physiologically reversible reaction.


Asunto(s)
Acinetobacter/enzimología , Genes Bacterianos , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Quinasas/genética , Acinetobacter/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN Bacteriano , Humanos , Datos de Secuencia Molecular , Fosforilación , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo
20.
FEBS Lett ; 445(1): 137-43, 1999 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-10069388

RESUMEN

The autophosphorylating protein, Ptk, of the bacterium Acinetobacter johnsonii was overproduced, purified to homogeneity and assayed for ATP binding by using the nucleotide analog 5'-p-fluorosulfonylbenzoyl adenosine. The ATP binding site of this bacterial autophosphorylating protein was found to be different from that generally used by eukaryotic protein kinases. It consists of two amino acid sequences that closely resemble the Walker motifs A and B. This observation was confirmed by site-directed mutagenesis experiments which showed, in addition, that the ATP molecule bound to these motifs is effectively employed by the bacterial protein to autophosphorylate on tyrosine. It is concluded that even though the overall autophosphorylation reaction is similar in eukaryotic and prokaryotic proteins, the mechanism involved is likely different.


Asunto(s)
Acinetobacter/enzimología , Adenosina Trifosfato/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Glutatión Transferasa/biosíntesis , Glutatión Transferasa/genética , Datos de Secuencia Molecular , Fosfatos , Fosforilación , Proteínas Tirosina Quinasas/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
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