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1.
Ann Oncol ; 35(1): 118-129, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37922989

RESUMEN

BACKGROUND: Optimal consolidation for young patilents with relapsed/refractory (R/R) follicular lymphoma (FL) remains uncertain in the rituximab era, with an unclear benefit of autologous stem cell transplantation (ASCT). The multicenter, randomized, phase III FLAZ12 (NCT01827605) trial compared anti-CD20 radioimmunotherapy (RIT) with ASCT as consolidation after chemoimmunotherapy, both followed by rituximab maintenance. PATIENTS AND METHODS: Patients (age 18-65 years) with R/R FL and without significant comorbidities were enrolled and treated with three courses of conventional, investigator-chosen chemoimmunotherapies. Those experiencing at least a partial response were randomized 1 : 1 to ASCT or RIT before CD34+ collection, and all received postconsolidation rituximab maintenance. Progression-free survival (PFS) was the primary endpoint. The target sample size was 210 (105/group). RESULTS: Between August 2012 and September 2019, of 164 screened patients, 159 were enrolled [median age 57 (interquartile range 49-62) years, 55% male, 57% stage IV, 20% bulky disease]. The study was closed prematurely because of low accrual. Data were analyzed on 8 June 2023, on an intention-to-treat basis, with a 77-month median follow-up from enrollment. Of the 141 patients (89%), 70 were randomized to ASCT and 71 to RIT. The estimated 3-year PFS in both groups was 62% (hazard ratio 1.11, 95% confidence interval 0.69-1.80, P = 0.6662). The 3-year overall survival also was similar between the two groups. Rates of grade ≥3 hematological toxicity were 94% with ASCT versus 46% with RIT (P < 0.001), and grade ≥3 neutropenia occurred in 94% versus 41%, respectively (P < 0.001). Second cancers occurred in nine patients after ASCT and three after radioimmunotherapy (P = 0.189). CONCLUSIONS: Even if prematurely discontinued, our study did not demonstrate the superiority of ASCT versus RIT. ASCT was more toxic and demanding for patients and health services. Both strategies yielded similar, favorable long-term outcomes, suggesting that consolidation programs milder than ASCT require further investigation in R/R FL.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Linfoma Folicular , Humanos , Masculino , Persona de Mediana Edad , Adolescente , Adulto Joven , Adulto , Anciano , Femenino , Linfoma Folicular/radioterapia , Radioinmunoterapia , Rituximab , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Supervivencia sin Enfermedad , Trasplante Autólogo , Trasplante de Células Madre
2.
Sci Rep ; 10(1): 16182, 2020 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-32999414

RESUMEN

Sphingolipids are structural components of cell membrane, displaying several functions in cell signalling. Extracellular vesicles (EV) are lipid bilayer membrane nanoparticle and their lipid composition may be different from parental cells, with a significant enrichment in sphingolipid species, especially in pathological conditions. We aimed at optimizing EV isolation from plasma and describing the differential lipid content of EV, as compared to whole plasma. As pilot study, we evaluated the diagnostic potential of lipidomic signature of circulating EV in patients with a diagnosis of ST-segment-elevation myocardial infarction (STEMI). STEMI patients were evaluated before reperfusion and 24-h after primary percutaneous coronary intervention. Twenty sphingolipid species were quantified by liquid-chromatography tandem-mass-spectrometry. EV-ceramides, -dihydroceramides, and -sphingomyelins increased in STEMI vs. matched controls and decreased after reperfusion. Their levels correlated to hs-troponin, leucocyte count, and ejection fraction. Plasma sphingolipids levels were 500-to-700-fold higher as compared to EV content; nevertheless, only sphingomyelins differed in STEMI vs. control patients. Different sphingolipid species were enriched in EV and their linear combination by machine learning algorithms accurately classified STEMI patients at pre-PCI evaluation. In conclusion, EV lipid signature discriminates STEMI patients. These findings may contribute to the identification of novel biomarkers and signaling mechanisms related to cardiac ischemia.


Asunto(s)
Vesículas Extracelulares/metabolismo , Isquemia Miocárdica/diagnóstico , Infarto del Miocardio con Elevación del ST/diagnóstico , Esfingolípidos/metabolismo , Anciano , Biomarcadores/sangre , Cromatografía Liquida , Diagnóstico Diferencial , Femenino , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/metabolismo , Intervención Coronaria Percutánea , Proyectos Piloto , Infarto del Miocardio con Elevación del ST/metabolismo , Espectrometría de Masas en Tándem
3.
Environ Sci Pollut Res Int ; 24(9): 8297-8301, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28161861

RESUMEN

This study aimed to assess the association between aryl hydrocarbon receptor (AhR) rs2066853 gene polymorphism with infertile oligoasthenoteratozoospermic (OAT) men and seminal oxidative stress (OS). A total of 170 Egyptian men were allocated according to their semen analysis into fertile normozoospermic controls (n = 50) and infertile OAT men (n = 120). They were subjected to history taking, clinical examination, semen analysis, estimation of seminal glutathione peroxidase (GPx), and malondialdehyde (MDA). AhR rs2066853 gene polymorphism was identified in the blood by PCR-RFLP. Comparing infertile OAT men with fertile controls, AhR rs2066853 genotypes showed decreased prevalence for wild homozygous genotype GG (35.8 vs 56%) and for heterozygous genotype GA (17.5 vs 30%) and an increased prevalence for homozygous genotype AA (46.7 vs 14%). Distribution of alleles of AhR rs2066853 among OAT men compared with fertile men showed decreased prevalence of G allele (44.6 vs 71%) and an increased prevalence of A allele (55.4 vs 29%). Seminal MDA demonstrated significant increase whereas seminal GPx demonstrated significant decrease in cases with AA and GA/AA genotypes compared to cases with GG genotype. It is concluded that there is a significant association between AhR rs2066853 genotype polymorphism with decreased sperm parameters as well as increased seminal oxidative stress in infertile OAT men.


Asunto(s)
Infertilidad Masculina/genética , Estrés Oxidativo/genética , Receptores de Hidrocarburo de Aril/genética , Adulto , Alelos , Estudios de Casos y Controles , Egipto , Fertilidad , Genotipo , Glutatión Peroxidasa/metabolismo , Humanos , Masculino , Malondialdehído/análisis , Polimorfismo Genético , Semen/metabolismo , Análisis de Semen , Espermatozoides/metabolismo
4.
Biochim Biophys Acta ; 993(2-3): 157-67, 1989 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-2512986

RESUMEN

The addition of proteinase inhibitors (1 mM phenylmethylsulfonyl fluoride, 10 mM N-ethylmaleimide, 0.25 mM benzamidine hydrochloride, 6.25 mM EDTA, 12.5 mM 6-aminohexanoic acid and 2 mM iodoacetic acid) to explant cultures of adult bovine articular cartilage inhibits proteoglycan synthesis as well as the loss of the macromolecule from the tissue. Those proteoglycans lost to the medium of explant cultures treated with proteinase inhibitors were either aggregates or monomers with functional hyaluronic acid-binding regions, whereas proteoglycans lost from metabolically active tissue also included a population of monomers that were unable to aggregate with hyaluronate. Analysis of the core protein from proteoglycans lost into the medium of inhibitor-treated cultures showed the same size distribution as the core proteins of proteoglycans present in the extracellular matrix of metabolically active cultures. The core proteins of proteoglycans appearing in the medium of metabolically active cultures showed that proteolytic cleavage of these macromolecules occurred as a result of their loss from the tissue. Explant cultures of articular cartilage maintained in medium with proteinase inhibitors were used to investigate the passive loss of proteoglycan from the tissue. The rate of passive loss of proteoglycan from the tissue was dependent on surface area, but no difference in the proportion of proteoglycan aggregate to monomer appearing in the medium was observed. Furthermore, proteoglycans were lost at the same rate from the articular and cut surfaces of cartilage. Proteoglycan aggregates and monomer were lost from articular cartilage over a period of time, which indicates that proteoglycans are free to move through the extracellular matrix of cartilage. The movement of proteoglycans out of the tissue was shown to be temperature dependent, but was different from the change of the viscosity of water with temperature, which indicates that the loss of proteoglycan was not solely due to diffusion. The activation energy for the loss of proteoglycans from articular cartilage was found to be similar to the binding energies for electrostatic and hydrogen bonds.


Asunto(s)
Cartílago Articular/metabolismo , Inhibidores de Proteasas/farmacología , Proteoglicanos/metabolismo , Ácido Aminocaproico/farmacología , Animales , Benzamidas/farmacología , Cartílago Articular/efectos de los fármacos , Bovinos , Técnicas de Cultivo , Ácido Edético/farmacología , Etilmaleimida/farmacología , Semivida , Concentración de Iones de Hidrógeno , Yodoacetatos/farmacología , Ácido Yodoacético , Sustancias Macromoleculares , Masculino , Fluoruro de Fenilmetilsulfonilo/farmacología , Propiedades de Superficie , Temperatura , Termodinámica
5.
Chem Commun (Camb) ; 51(47): 9686-9, 2015 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-25977948

RESUMEN

By means of confocal photoluminescence measurements and fs pump-probe spectroscopy, we observe the optical properties of phase separation in a mixture of polyfluorene and Liquid Crystals (LCs). The boundaries of LC-rich micro-domains display a large polarized gain region from keto defects stemming from the single-chain nature of this defect.

6.
Br J Ophthalmol ; 85(2): 143-6, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11159475

RESUMEN

BACKGROUND/AIMS: Current contact lenses (CLs) when worn on an extended wear basis cause corneal epithelial alterations. The aim of this study was to evaluate changes in corneal epithelial cell morphology and physiology following short term (3 months) wear of highly oxygen permeable CLs and to compare this with disposable CLs. METHODS: Subjects were wearers of highly oxygen permeable CLs (n=11, wearing CLs on a 30 night schedule), disposable CL users (n=6, wearing CLs on a 6 night schedule), and non-CL wearers (n=20). Mean CL wear experience was 3 months. Epithelial cells were harvested using corneal cytology and were stained using acridine orange and ethidium bromide. Epithelial cell size and viability were determined. RESULTS: The majority of epithelial cells recovered were non-viable (71%), and the mean longest cell diameter was 38 (SD 8) microm. Disposable CLs caused an increase in cell size (42 (7) microm) compared with both non-wear (39 (7) microm, p=0.01) and wear of highly oxygen permeable CLs (37 (10) microm, p=0.0049). There was no difference in cell viability between groups. CONCLUSIONS: Extended wear of disposable CLs caused an 8% increase in cell diameter in harvested corneal epithelial cells following 3 months of CL wear. Cells harvested following 3 months' wear of highly oxygen permeable CLs were indistinguishable from those recovered from non-CL wearers.


Asunto(s)
Tamaño de la Célula , Lentes de Contacto de Uso Prolongado , Epitelio Corneal/citología , Adulto , Análisis de Varianza , Supervivencia Celular , Lentes de Contacto Hidrofílicos , Equipos Desechables , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/química , Permeabilidad , Manejo de Especímenes/métodos , Factores de Tiempo
7.
Anticancer Res ; 20(3B): 2103-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10928160

RESUMEN

Interleukin-2 (IL-2) has proven to be able to generate an effective anticancer immunity against both solid and hematologic malignancies. Moreover, recent advances in the knowledge of psychoneuroimmunology have demonstrated that anticancer immunity is under neuroendocrine control and that the pineal hormone melatonin (MLT) may stimulate the IL-2-dependent anticancer reaction. Finally, preliminary clinical studies have already shown that the concommitant administration of MLT may amplify the efficacy of IL-2 in the treatment of advanced solid neoplasms, whereas there are no data about MLT influence on IL-2 activity in hematologic malignancies. The aim of the present study was to evaluate the efficacy and tolerability of a neuroimmunotherapeutic combination of low-dose IL-2 plus MLT in advanced hematologic malignancies which did not respond to previous standard therapies. The study included 12 evaluable patients. Tumor histotypes were as follows: non-Hodgkin's lymphoma (NHL) 6; Hodgkin's disease (HD), 2; multiple myeloma, 2; acute myelogenous leukemia (ALM), 1 and chronic myelomonocytic leukemia (CMML), 1. IL-2 was injected subcutaneously at a dose of 3 million IU/day for 6 days per week for 4 weeks, corresponding to one cycle. MLT was given orally at 20 mg/day in the evening, without interruption. In non-progressing patients, a second IL-2 cycle was planned after a 3 week-rest period. A partial response was achieved in one patient with multiple myeloma. Stable disease occurred in 7 other patients (NHL, 3; HD, 1; AML, 1; CLLM, 1; multiple myeloma, 1), whereas the other 4 patients progressed. Therefore, lack of progression was obtained in 8 out of 12 (67%) patients, with a median duration of 21+ months (14-30+ months). The treatment was well tolerated in all patients. These preliminary results would suggest that the concomitant administration of low-dose IL-2 plus the pineal hormone MLT may prolong the survival time in untreatable advanced hematologic malignancies, with results comparable to those previously reported using a more toxic immunotherapy, consisting of high-dose IL-2 alone.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias Hematológicas/tratamiento farmacológico , Factores Inmunológicos/uso terapéutico , Interleucina-2/uso terapéutico , Melatonina/uso terapéutico , Neuroinmunomodulación , Adolescente , Adulto , Anciano , Antineoplásicos Hormonales/administración & dosificación , Terapia Combinada , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Neoplasias Hematológicas/mortalidad , Neoplasias Hematológicas/patología , Humanos , Factores Inmunológicos/administración & dosificación , Inyecciones Subcutáneas , Interleucina-2/administración & dosificación , Masculino , Melatonina/administración & dosificación , Persona de Mediana Edad , Proteínas de Neoplasias/análisis , Análisis de Supervivencia , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/análisis
8.
Int J Biol Markers ; 14(3): 167-71, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10569139

RESUMEN

Tumor necrosis factor-alpha (TNF-alpha), a cytokine provided by both immunomodulating and inflammatory activities, has been described to be abnormally increased in the blood of patients affected by malignant lymphomas, particularly NHL. However, the biological and clinical significance of TNF-alpha secretion in malignant lymphomas is still controversial. The present study was carried out to further define TNF-alpha secretion in untreated malignant lymphomas and during low-dose IL-2 immunotherapy. The study included 80 malignant lymphoma patients, 54 of whom were affected by HD and the other 26 by NHL. The mean TNF-alpha serum concentrations observed in untreated lymphoma patients were significantly higher than those seen in the healthy controls, without significant differences between HD and NHL. Moreover, both HD and NHL lymphoma patients at clinical stage III-IV showed significantly higher mean TNF-alpha levels than those at clinical stage I-II. Finally, patients with systemic symptoms had higher mean TNF-alpha concentrations than those without any systemic symptoms, even though statistical significance was observed only for NHL patients. In a second study we have evaluated changes in TNF-alpha levels in seven evaluable lymphoma patients (NHL: 6; HD: 1)--who did not respond to conventional therapies--during subcutaneous low-dose IL-2 (3 MIU/day, 6 days/week for 4 weeks). Long-term stable disease was achieved in four patients with NHL, whereas the other three progressed. In patients with stable disease the mean TNF-alpha concentrations significantly decreased during treatment, whereas they increased in progressing patients. This study, by showing an abnormally enhanced TNF-alpha secretion in both NHL and HD patients with advanced disease and systemic symptoms and a decrease in its levels in patients who achieved disease control on IL-2 immunotherapy, appears to confirm the unfavorable prognostic significance of enhanced TNF-alpha levels in malignant lymphomas.


Asunto(s)
Interleucina-2/uso terapéutico , Linfoma/terapia , Factor de Necrosis Tumoral alfa/análisis , Adolescente , Adulto , Anciano , Femenino , Humanos , Linfoma/sangre , Linfoma/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias
9.
Tumori ; 81(4): 245-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8540120

RESUMEN

AIMS AND BACKGROUND: Recombinant alpha-interferon has been shown to be effective in essential thrombocythemia and in thrombocytosis associated with other myeloproliferative disorders. PATIENTS AND METHODS: Twenty-five untreated patients were enrolled in our study from May 1989 to April 1992. Recombinant alpha interferon-2b was administered at an initial dose of 2 megaunits (MU)/m2 three times a week at escalating doses to 5 MU/m2 or the maximum tolerated dose. The mean follow-up for patients still in treatment at the time of this report was 35.9 months (range, 24-63). RESULTS: Fourteen patients (56%) had achieved a complete remission by a mean time of 152 days; 6 patients (24%) had achieved a good partial remission by a mean of 180 days. In addition to the favorable effect on platelet count, a marked improvement in clinical symptoms was observed. Treatment had to be discontinued in 9 patients (36%), 5 for toxicity (3 neurologic, 1 anemia and 1 severe hypertriglyceridemia) at a median of 155 days from the beginning of therapy (range, 30-400). Four patients refused to continue therapy because of low tolerance (flu-like syndrome) at mean of 160 days from the beginning of therapy (range, 34-301). CONCLUSIONS: In our study, lower doses were administered compared with previous short-time trials. The present data show that interferon is an effective alternative to cytostatic agents in long-term treatment of patients with essential thrombocythemia, even when used at lower dosages.


Asunto(s)
Interferón-alfa/uso terapéutico , Trombocitosis/tratamiento farmacológico , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Interferón-alfa/efectos adversos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes , Resultado del Tratamiento
10.
Clin Drug Investig ; 15(5): 425-33, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-18370498

RESUMEN

To assess the economic outcomes produced when a conventional antibiotic treatment regimen requiring three administrations per day was replaced with a treatment regimen requiring only one daily administration, the efficacy, tolerability and cost of ceftazidime was compared with that of ceftriaxone (both drugs in combination with amikacin) for the empirical treatment of febrile granulocytopenic patients with haematological malignancy. 102 febrile patient-episodes were randomly assigned to receive ceftazidime (6g in three divided doses) or ceftriaxone (2g as a single daily dose), both in combination with amikacin. The response was evaluable in 94 patients (47 in each group). 75 (80%) patients had an absolute granulocyte count lower than 100/mm(3) at the onset of fever or during the first week of antibiotic therapy. 61 (64.9%) were affected by acute leukaemia. Multiple daily ceftazidime plus amikacin was effective in 33 of 47 (70.2%) patients, and single daily ceftriaxone plus amikacin in 31 of 47 (66%) patients (p > 0.2). Among patients successfully treated, median time to defervescence was 3.3 days (range 1 to 11) for ceftazidime plus amikacin and 4.5 days for ceftriaxone plus amikacin (range 1 to 15) [p = 0.14]; study drugs were continued for 12 (range 7 to 26) and 12.3 days (range 7 to 28), respectively. Our study demonstrated that single daily administration of ceftriaxone was as effective and well tolerated as multiple daily administration of ceftazidime when both were administered in combination with amikacin. Cost analysis showed that compared with the thrice daily regimen, administration of single daily doses of ceftriaxone for a 12-day treatment period would result in a net cost saving of $US392 (626 940 Italian lire).

11.
Clin Ter ; 128(6): 387-400, 1989 Mar 31.
Artículo en Italiano | MEDLINE | ID: mdl-2524325

RESUMEN

Some problems of non-Hodgkin's lymphomas are examined, with special consideration for those related to treatment. Some questions of staging are also considered, together with some particular presentations, such as bulky diseases, central nervous system localizations, lymphoblastic lymphoma. The unique features of this disease in immunocompromised patients and problems related to the growing numbers of older patients eligible for curative treatment are discussed.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma no Hodgkin/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Humanos , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias
12.
Recenti Prog Med ; 81(6): 448-52, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2251455

RESUMEN

We have retrospectively examined 35 cases of non-Hodgkin's lymphoma (NHL) with gastric involvement at the onset. All patients have completed induction therapy at the time of this report. Histologic specimens have been classified according to the Working Formulation. Patients have undergone surgery and/or chemotherapy. Twenty out of 22 patients with stage I or II disease had surgery. Seventeen out of 20 gastrectomized patients achieved complete remission (11 with stage I and 6 with stage II): Fifteen of these are in their first complete remission with median follow-up of 24 months (range 8-68). Three patients with stage IV had surgery, two of which achieved CR. These data confirm that combined therapy is useful in gastric NHL presenting with stage I and II; no conclusions can be drawn regarding disseminated disease.


Asunto(s)
Linfoma no Hodgkin/terapia , Neoplasias Gástricas/terapia , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Combinada , Femenino , Gastrectomía , Humanos , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/cirugía
13.
Recenti Prog Med ; 85(1): 49-55, 1994 Jan.
Artículo en Italiano | MEDLINE | ID: mdl-8184181

RESUMEN

Patients affected with multiple myeloma constitute an heterogeneous population with very different clinical patterns, varying from asymptomatic to very compromised patients with severe and uncontrolled disease. Most common clinical and biological staging systems have been in use for many years. Recently new prognostic factors have been identified; among them, serum levels of beta-2 microglobulin, C-reactive protein and interleukin-6 employed with already known parameters have been useful in the new staging system, permitting a more focalized therapy. As today is not yet possible to define the best treatment schedule, as the most common treatments are incapable to eradicate myeloma neoplastic clone even in responsive patients. Nevertheless extensive use of biologic response modifiers in the last years, as alpha interferon, have added new powerful and hopeful therapeutic tools even if the results need to be confirmed in future trials. It is important to remind the primary role of bone marrow transplantation associated with high dose polychemotherapy even if just a minority of patients is eligible for this therapeutic chance.


Asunto(s)
Mieloma Múltiple/patología , Mieloma Múltiple/terapia , Predicción , Humanos , Mieloma Múltiple/diagnóstico , Estadificación de Neoplasias/métodos , Pronóstico
16.
Agents Actions ; 32(3-4): 299-304, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1862748

RESUMEN

Articular cartilage proteoglycan biosynthesis was substantially inhibited by the competitive glycolytic inhibitor 2-deoxyglucose (approximately 65% at 100 mM), but to a much lesser degree (approximately 10%) by the oxidative phosphorylation uncoupler, 2,4-dinitrophenol. These results confirm that articular cartilage proteoglycan synthesis mostly utilises ATP which is generated by glycolysis. In addition, we have utilised the loss of the relatively specific labelling of glyceraldehyde-3-phosphate dehydrogenase (G3PDH) by [3H]-iodoacetic acid to show that rabbit articular G3PDH is oxidised in vivo during the animal model of acute arthritis, carrageenin-induced arthritis, in the same way as we have previously shown that cartilage G3PDH is oxidised after in vitro exposure to sublethal doses of H2O2. The oxidation of rabbit G3PDH in vivo (18 hr post-injection) corresponds with the maximal influx of PMNL cells into the arthritic synovial fluid and with substantial inhibition of proteoglycan core protein synthesis. We propose that H2O2 released from "activated" PMNLs and macrophages is responsible for the "down-regulation" of biosynthetic processes found in cartilage during acute inflammation.


Asunto(s)
Artritis/metabolismo , Carragenina , Cartílago Articular/metabolismo , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , 2,4-Dinitrofenol , Adenosina Trifosfato/metabolismo , Animales , Artritis/inducido químicamente , Desoxiglucosa/farmacología , Dinitrofenoles/farmacología , Femenino , Glucólisis/efectos de los fármacos , Yodoacetatos/metabolismo , Ácido Yodoacético , Oxidación-Reducción , Fosforilación Oxidativa/efectos de los fármacos , Proteoglicanos/biosíntesis , Conejos
17.
J Autom Methods Manag Chem ; 25(2): 35-42, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-18924714

RESUMEN

The precision characteristics of the absorbance measurements obtained with a low-cost miniature spectrometer incorporating an array detector were evaluated. Uncertainties in absorbance measurements were due to a combination of non-uniform light intensity and detector response over the wavelength range examined (350-850 nm), in conjunction with the digitization of the intensity indications and the intrinsic noise of the detecting elements. The precision characteristics are presented as contour plots displaying the expected RSD% of absorbances on the absorbance versus wavelength plane. The minimum RSD% for the spectrometer configuration tested was observed within the 0.2-1.5 absorbance units and 500-750 nm wavelength range. Without invoking signal enhancement features of the data-acquisition program (scan average, higher integration times, smoothing based on averaging the signal detected by adjacent pixels), the attainable precision within this range was 0.4-0.8%. A computer program based on Monte Carlo simulations was developed for the prediction of absorbance precision characteristics under various conditions of measurements.

18.
Haematologica ; 78(5): 332-4, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8314164

RESUMEN

A case of non-Hodgkin lymphoma involving the heart is described; the patient suffered for atrial flutter, followed by sick sinus syndrome for one year before diagnosis was made. Although it is not possible to demonstrate primary cardiac onset, the clinical history is highly suggestive. Most recent cases described occurred in immunodeficient patients. Interestingly our patient showed no evidence of immunodeficiency. Our patient received conventional chemotherapy followed by radiotherapy, obtaining complete remission without complications, and remains in this condition after a 3-year follow-up. The patient's good condition may be responsible for this successful outcome.


Asunto(s)
Aleteo Atrial/etiología , Neoplasias Cardíacas/complicaciones , Linfoma de Células B/complicaciones , Síndrome del Seno Enfermo/etiología , Humanos , Masculino , Persona de Mediana Edad
19.
Arch Biochem Biophys ; 316(1): 596-606, 1995 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-7840671

RESUMEN

The addition of hyaluronan to the culture medium of explant cultures of articular cartilage was shown to suppress the synthesis of hyaluronan and aggrecan, the major proteoglycan present in cartilage, and resulted in a greater proportion of the newly synthesized aggrecan and hyaluronan appearing in the culture medium. This effect of exogenous hyaluronan on aggrecan and hyaluronan synthesis was concentration-dependent and reversible on removal of the glycosaminoglycan from the culture medium. The addition of tetra- and hexasaccharides derived from Streptomyces sp. hyaluronidase digestion of hyaluronan to explant cultures of articular cartilage did not change the rate of synthesis of aggrecan or hyaluronan or their ultimate distribution between tissue and medium. However, the addition of tetra- and hexasaccharides of hyaluronan resulted in a decrease in the rate of loss of hyaluronan from the tissue but not that of aggrecan, which remained the same as in control cultures. This suppression of the rate of loss of hyaluronan was eliminated on removal of the hyaluronan oligosaccharides from the culture medium. Analysis of the hydrodynamic size of the newly synthesized hyaluronan indicated that the presence of hyaluronan tetra- and hexasaccharides brought about an accumulation of hyaluronan of intermediate molecular mass. Since no radiolabeled hyaluronan was detected in the culture medium, it was concluded that the tetra- and hexasaccharides inhibited the internalization and intracellular catabolism of hyaluronan by the cartilage explant cultures. Regardless of whether hyaluronan or tetra- and hexasaccharides of hyaluronan were added to the culture medium, newly synthesized hyaluronan underwent depolymerization at a rate consistent with a mechanism involving oxygen-derived radicals.


Asunto(s)
Cartílago Articular/metabolismo , Proteínas de la Matriz Extracelular , Ácido Hialurónico/metabolismo , Proteoglicanos/metabolismo , Adulto , Agrecanos , Animales , Bovinos , Células Cultivadas , Medios de Cultivo , Relación Dosis-Respuesta a Droga , Radicales Libres , Humanos , Ácido Hialurónico/farmacología , Técnicas In Vitro , Lectinas Tipo C , Peso Molecular , Oligosacáridos/farmacología , Streptomyces/química
20.
Biochem J ; 240(2): 423-30, 1986 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-3545187

RESUMEN

The addition of foetal calf serum to explant cultures of adult bovine articular cartilage is known to stimulate proteoglycan synthesis in a dose-dependent manner. We have now shown the activity in serum responsible for this effect to be heat- and acid-stable, to be associated with a high-Mr complex in normal serum but converted to a low-Mr form under acid conditions. The activity has an apparent Mr approximately 10,000 and isoelectric points similar to those reported for insulin-like growth factors (IGFs). Addition of a monoclonal antibody against insulin-like growth factor-I (IGF-I) prevented foetal calf serum from stimulating proteoglycan synthesis. Physiological concentrations of recombinant IGF-I or pharmacological levels of insulin when added to cartilage cultures mimicked the proteoglycan-stimulatory activity of serum. IGF-I appeared to act by increasing the rate of proteoglycan synthesis and did not change the nature of the proteoglycan synthesized nor the rate of proteoglycan catabolism by the tissue, suggesting that IGF-I may be important in the regulation of proteoglycan metabolism in adult articular cartilage. Furthermore, IGF-I can replace foetal calf serum in the culture medium, thereby allowing the use of a fully-defined medium which will maintain the synthesis and tissue levels of proteoglycan in adult articular cartilage explants for up to 5 days.


Asunto(s)
Cartílago Articular/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Proteoglicanos/biosíntesis , Somatomedinas/farmacología , Animales , Anticuerpos Monoclonales , Sangre , Cartílago Articular/efectos de los fármacos , Bovinos , Cromatografía en Gel , Técnicas de Cultivo , Hormona del Crecimiento/farmacología , Insulina/farmacología , Proteínas Recombinantes/farmacología , Estimulación Química , Temperatura
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