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1.
Am J Transplant ; 13(11): 2797-804, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24103029

RESUMEN

Transplantation is invariably associated with ischemia-reperfusion injury (IRI), inflammation and rejection. Resultant cell death has morphological features of necrosis but programmed cell death has been synonymous with apoptosis until pathways of regulated necrosis (RN) have been described. The best-studied RN pathway, necroptosis, is triggered by perturbation of caspase-8-mediated apoptosis and depends on receptor-interacting protein kinases 1 and 3 (RIPK1/RIPK3) as well as mixed linage kinase domain like to form the necroptosome. The release of cytosolic content and cell death-associated molecular patterns (CDAMPs) can trigger innate and promote adaptive immune responses. Thus, the form of cell death can substantially influence alloimmunity and graft survival. Necroptosis is a key element of IRI, and RIPK1 interference by RN-specific inhibitors such as necrostatin-1 protects from IRI in kidney, heart and brain. Necroptosis may be a general mechanism in response to other forms of inflammatory organ injury, and will likely emerge as a promising target in solid organ transplantation. As second-generation RIPK1 and RIPK3 inhibitors become available, clinical trials for the prevention of delayed graft function and attenuation of allograft rejection-mediated injury will emerge. These efforts will accelerate upon further identification of critical necroptosis-triggering receptor(s).


Asunto(s)
Inmunidad Celular , Necrosis , Daño por Reperfusión/patología , Animales , Humanos
2.
Nat Med ; 3(10): 1124-8, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9334724

RESUMEN

Interleukin-15 shares many biological activities with IL-2 and signals through the IL-2 receptor beta and gamma chains. However, IL-15 and IL-2 differ in their controls of expression and secretion, their range of target cells and their functional activities. These dissimilarities may include differential effects on apoptosis. For example, IL-2 induces or inhibits T-cell apoptosis in vitro, depending on T-cell activation, whereas IL-15 inhibits cytokine deprivation-induced apoptosis in activated T cells. Studying whether and how IL-15 modulates distinct apoptosis pathways, we show here that apoptosis induced by anti-Fas, anti-CD3, dexamethasone, and/or anti-IgM in activated human T and B cells in vitro is inhibited by IL-15 in a manner dependent on RNA synthesis. In vivo, anti-Fas-induced lethal multisystem apoptosis in mice is suppressed by a novel IL-15-IgG2b fusion protein. Only IL-15, but not IL-2, completely protected from lethal hepatic failure. Thus, IL-15 is a potent, general inhibitor of apoptosis in vitro and in vivo with intriguing therapeutic potential.


Asunto(s)
Apoptosis/efectos de los fármacos , Linfocitos B/inmunología , Interleucina-15/farmacología , Linfocitos T/inmunología , Animales , Apoptosis/inmunología , Linfocitos B/citología , Linfocitos B/efectos de los fármacos , Complejo CD3/inmunología , Complejo CD3/fisiología , Células Cultivadas , Fragmentación del ADN , Dexametasona/farmacología , Humanos , Inmunoglobulina G/farmacología , Inmunoglobulina M/farmacología , Activación de Linfocitos , Ratones , Tonsila Palatina , Proteínas Recombinantes de Fusión/farmacología , Linfocitos T/citología , Linfocitos T/efectos de los fármacos , Transcripción Genética , Receptor fas/inmunología , Receptor fas/fisiología
3.
J Exp Med ; 178(1): 355-60, 1993 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8315391

RESUMEN

Tumor necrosis factor (TNF) produced by tumor cells after gene transfer can effectively suppress the growth of locally growing tumors. We wanted to test the effects of "local" TNF on the growth of a highly metastatic cell line. Therefore, a recombinant retrovirus allowing expression of the TNF gene by the beta-actin promotor has been constructed and used to infect the two tumor cell lines EB and ESB, which grow as solid tumor or metastasize, respectively. Expression of TNF by EB cells resulted in their rapid and dose-dependent rejection. In sharp contrast, mice injected with ESB cells producing similar amounts of TNF showed no signs of tumor suppression, but rather had reduced survival rates that correlated with enhanced hepatic metastases. The accelerated formation of liver metastases by ESB TNF cells could be reversed by an anti-TNF mAb. These results demonstrate the opposite effects TNF may have on tumor growth: suppression of a locally growing tumor and promotion of metastasis formation.


Asunto(s)
Metástasis de la Neoplasia , Neoplasias Experimentales/patología , Factor de Necrosis Tumoral alfa/biosíntesis , Animales , Secuencia de Bases , Moléculas de Adhesión Celular/fisiología , Inmunoterapia , Ratones , Ratones Endogámicos DBA , Datos de Secuencia Molecular , Neoplasias Experimentales/metabolismo , Transfección , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/genética
4.
Urologe A ; 58(8): 888-892, 2019 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-31161234

RESUMEN

BACKGROUND: The number of organ donations in Germany decreased by 32.3% between 2010 and 2017. For this reason, more than 1500 fewer organ transplantations were performed in 2017 than in 2010. QUESTION: What are the causes of this development? METHODS: Analysis of available statistics and scientific publications. RESULTS: A decline of the organ donation potential can be ruled out as the cause of the declining organ donation figures, since the number of patients who were eligible for organ donation from a medical point of view increased during the period under consideration. Similarly, there is no indication that a change in the population's attitude towards organ donation can be held responsible for this development. The decline is rather due to a recognition and reporting deficit of potential organ donors. The extent of this deficit differs considerably between different hospitals and is not only responsible for the decline in the donor rate in recent years, but also for the low donor numbers in Germany by international standards. CONCLUSION: The low organ donation figures in Germany are due to a recognition and reporting deficit. The number of organ donations could be considerably increased by improving the internal processes in hospitals.


Asunto(s)
Donantes de Tejidos , Obtención de Tejidos y Órganos/estadística & datos numéricos , Alemania , Humanos
5.
Urologe A ; 58(11): 1313-1323, 2019 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-31659368

RESUMEN

In this review article, the authors describe all relevant aspects of the new S2k guideline from the German Society of Urology (Deutschen Gesellschaft für Urologie, DGU) for the diagnosis and treatment of IC/PBS (interstitial cystitis/painful bladder syndrome). A list of necessary and optional examinations and the necessity of diagnosis of exclusion are summarized and evaluated. The treatment options listed (ranging from conservative, oral drug, and complementary medicine to interventional surgical procedures) also give the reader a good overview of the contents of the guideline and possible therapeutic approaches. Finally, the recommendations including consensus of the guideline group are also summarized in various information boxes.


Asunto(s)
Cistitis Intersticial/diagnóstico , Cistitis Intersticial/terapia , Guías de Práctica Clínica como Asunto , Urología/normas , Alemania , Humanos , Dolor , Examen Físico , Sociedades Médicas
6.
Transplant Proc ; 50(10): 3010-3016, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30577160

RESUMEN

BACKGROUND: Since 2014, expected graft and recipient survival are matched by the U.S. kidney allocation system to improve organ utility. This mechanism is based on the kidney donor profile index (KDPI) and the estimated posttransplant survival score (EPTS). Here we analyzed 1. the transferability of these scores into the Eurotransplant (ET) region and 2. the extent to which the ET kidney allocation algorithm promotes utility. METHODS: We studied data of 262 kidney transplantations performed at the University Hospital Kiel between 2000 and 2009 (median follow-up, 9.94 years). RESULTS: Multivariable Cox regression analysis revealed that only the variables donor age of the KDPI and recipient's age of the EPTS have a significant value as predictors of posttransplant graft and recipient survival. The other variables showed no additional predictive value. Analyzing all kidneys allocated in the ET kidney allocation system and the European Senior Program, we found that donor and recipient's age and KDPI and EPTS were weakly correlated (rage-age = 0.5, P < .001; rKDPI-EPTS = 0.4, P < .01). If both programs were analyzed separately, no correlation between donor and recipient's age and between KDPI and EPTS was detected. CONCLUSION: The ET kidney allocation algorithm poorly matched predicted graft and recipient survival at our center. A better age-matching may improve organ utility.


Asunto(s)
Algoritmos , Selección de Donante/métodos , Trasplante de Riñón , Donantes de Tejidos/provisión & distribución , Adulto , Anciano , Europa (Continente) , Femenino , Supervivencia de Injerto , Humanos , Trasplante de Riñón/mortalidad , Masculino , Persona de Mediana Edad , Estados Unidos
7.
Clin Pharmacol Ther ; 81(2): 228-34, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17192769

RESUMEN

It is currently not clear whether the concentration-time curves of the immunosuppressants differ with respect to the CYP3A5, MDR1, or MRP2 genotype in dose-adapted stable kidney transplant patients. Dose/trough concentration ratios were obtained in 134 tacrolimus and 20 sirolimus-treated patients, and plasma concentration-time profiles were obtained from 16 (tacrolimus) and 10 (sirolimus) patients. Genotyping was carried out for CYP3A5 6986A>G; ABCB1 2677G>T/A, 3435C>T and ABCC2 -24C>T; 1249G>A; 3972C>T. Dose/trough concentration ratios were 0.67+/-0.3 and 1.36+/-0.73 x 10(3) l (P<0.00001) for tacrolimus and 0.42+/-0.17 and 0.84+/-0.46 x 10(3) l (P=0.18) for sirolimus in CYP3A5 non-expressors and expressors. The unadjusted tacrolimus area under curve (AUC)(0-12) was 106.8+/-17.5 ng/ml x h compared with 133.3+/-42.2 ng/ml x h (P=0.37) without affecting serum creatinine. Mean unadjusted AUC(0-24) of sirolimus did not differ significantly either. Therefore, CYP3A5 expressor status and not transporter variants is a main determinant of oral clearance, particularly for tacrolimus. Dose adaptation according to trough levels, however, appears to be sufficient to maintain similar concentration-time profiles.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Trasplante de Riñón , Sirolimus/farmacocinética , Tacrolimus/farmacocinética , Adulto , Anciano , Área Bajo la Curva , Disponibilidad Biológica , Bloqueadores de los Canales de Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacocinética , Bloqueadores de los Canales de Calcio/uso terapéutico , Citocromo P-450 CYP3A , Sistema Enzimático del Citocromo P-450/metabolismo , Quimioterapia Combinada , Femenino , Variación Genética , Genotipo , Semivida , Humanos , Inmunosupresores/metabolismo , Inmunosupresores/farmacocinética , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/metabolismo , Ácido Micofenólico/farmacocinética , Ácido Micofenólico/uso terapéutico , Prednisolona/metabolismo , Prednisolona/farmacocinética , Prednisolona/uso terapéutico , Sirolimus/metabolismo , Sirolimus/uso terapéutico , Tacrolimus/metabolismo , Tacrolimus/uso terapéutico
8.
J Clin Invest ; 97(5): 1204-10, 1996 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-8636431

RESUMEN

Interleukin-2 (IL-2) plays a pivotal role in the cellular and humoral immune responses directed against foreign antigens. We characterized the in vitro and in vivo properties of a chimeric protein consisting of mouse IL-2 fused to the mouse IgG2b Fc domains. This fusion protein binds to IL-2 and Fc receptors and supports IL-2-dependent cell proliferation but does not mediate lysis of IL-2 receptor-positive cells in the presence of murine complement in vitro. However, in vivo the IL2-IgG2b fusion protein suppresses both cellular and humoral immune responses after immunization with sheep erythrocytes. Surprisingly, delayed hypersensitivity is inhibited despite a dramatic increase of splenic CD3+ and NK1.1+ lymphocytes, indicating that altered homing of IL2-IgG2b-activated lymphocytes rather than cytolysis prevents these cells from accumulating in areas of inflammation. Although in vitro the IL2-IgG2b fusion protein does not alter proliferation of B cells in response to mitogenic stimulation, IgM production in response to sheep erythrocytes is profoundly inhibited in mice treated with the IL2-IgG2b fusion protein. Since no side effects are observed, the IL2-IgG2b fusion protein may expand the therapeutic repertoire of reagents used for the treatment of allograft rejection and autoimmune diseases.


Asunto(s)
Inmunoglobulina G/farmacología , Inmunosupresores/farmacología , Interleucina-2/farmacología , Proteínas Recombinantes de Fusión/farmacología , Animales , Formación de Anticuerpos/efectos de los fármacos , Femenino , Hipersensibilidad Tardía , Inmunoglobulina G/metabolismo , Interleucina-2/metabolismo , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL
9.
Cancer Res ; 53(4): 714-6, 1993 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-7679048

RESUMEN

The potential of tumor cells (J558L) engineered to produce one of 5 different cytokines (interleukin 2, interleukin 4, interleukin 7, tumor necrosis factor, or gamma-interferon) to give rise to systemic immunity protective against a contralateral challenge with the parental cells was analyzed. The rejection of all cytokine-producing cells appeared to induce some systemic response capable of mediating the rejection of low numbers of subsequently contralaterally injected cells, but the effect was much less obvious with higher cell numbers. The injection of any possible combination of two of the cytokine producers did not reveal any synergistic effects. The cytokine gene-transfected tumor cells were not superior to the parental cells admixed with the adjuvant Corynebacterium parvum with respect to their potential as immunogens to induce immunity.


Asunto(s)
Vacuna BCG/administración & dosificación , Interferones/biosíntesis , Interleucina-2/biosíntesis , Interleucina-4/biosíntesis , Interleucina-7/biosíntesis , Plasmacitoma/metabolismo , Plasmacitoma/prevención & control , Transfección , Factor de Necrosis Tumoral alfa/biosíntesis , Animales , Sinergismo Farmacológico , Femenino , Interferones/genética , Interleucina-2/genética , Interleucina-4/genética , Interleucina-7/genética , Ratones , Ratones Endogámicos BALB C , Trasplante de Neoplasias , Plasmacitoma/genética , Plasmacitoma/inmunología , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/genética
10.
Cancer Res ; 54(4): 1109-12, 1994 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-7508820

RESUMEN

The adhesion molecules E-selectin (ELAM-1) and P-selectin (GMP-140/CD62) recognize the carbohydrate motives sialyl-Le(x), sialyl-diLe(x), or sialyl-Lea, though with different affinity. We found that the melanoma cell line NKI-4 bound to E-selectin, but not to P-selectin. This melanoma cell line did not express sialyl-Le(x), but was positive for sialyl-diLe(x) and sialyl-Le(a). In contrast, 2 other melanoma cell lines, MeWo and SK-MEL-28, expressing either sialyl-diLe(x) or sialyl-Le(a) on the cell surface, bound neither E-selectin nor P-selectin. Transfection of the fucosyltransferases Fuc-TIII, Fuc-TIV, and Fuc-TV mediates cell surface expression of sialyl-Le(x) in many cell lines. We detected transcripts of the fucosyltransferases Fuc-TIII and Fuc-TV in 4 melanoma cell lines despite the absence of cell surface sialyl-Le(x). Our observations indicate that expression of fucosyltransferases (Fuc-TIII and -TV) and generation of cell-surface sialyl-diLe(x) are not sufficient to permit adherence to E-selectin or P-selectin. Furthermore, it seems possible that a yet undefined ligand different from sialyl-Le(x), sialyl-diLe(x), or sialyl-Le(a) enables melanoma cells to adhere to E-selectin.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Antígeno Lewis X/análisis , Melanoma/metabolismo , Glicoproteínas de Membrana Plaquetaria/metabolismo , Secuencia de Bases , Adhesión Celular , Selectina E , Citometría de Flujo , Fucosiltransferasas/genética , Humanos , Melanoma/patología , Datos de Secuencia Molecular , Selectina-P , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , Células Tumorales Cultivadas
11.
Cancer Res ; 58(13): 2707-10, 1998 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-9661877

RESUMEN

Here we provide proof that the injection of tumor cells engineered to secrete interleukin 2 (IL-2)-IgG chimeric proteins locally induces potent antitumor responses, which are more effective than tumor transfection with IL-2 alone. Murine plasmacytoma cells (J558L) were stably transfected with DNA coding for a human IL-2-IgG1 or a murine IL-2-IgG2b fusion protein and were injected s.c. into syngeneic BALB/c mice. Evaluation of tumor growth and rejection patterns showed that IL-2-IgG secretion by transfected J558L tumor cells induced their rejection in all animals tested, similar to the rejection of J558L cells engineered to secrete IL-2 alone, whereas treatment with parental cells was lethal. However, mice treated with IL-2-IgG-secreting J558L cells (human IL-2-IgG1 and murine IL-2-IgG2b) exhibited a significantly stronger tumor immunity against a later challenge with parental J558L cells than mice treated with IL-2-secreting tumor cells.


Asunto(s)
Rechazo de Injerto , Inmunoglobulina G/metabolismo , Interleucina-2/metabolismo , Trasplante de Neoplasias/inmunología , Plasmacitoma/terapia , Proteínas Recombinantes de Fusión/metabolismo , Transfección , Vacunación , Animales , Humanos , Inmunoglobulina G/genética , Interleucina-2/genética , Ratones , Ratones Endogámicos BALB C , Plasmacitoma/genética , Plasmacitoma/inmunología , Proteínas Recombinantes de Fusión/genética
12.
Transplantation ; 56(5): 1213-7, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7504345

RESUMEN

A crucial step in an effective immune response is the adhesion of circulating lymphocytes. Lymphocytes must attach to endothelial cells before they can migrate into the graft. It has been shown that T cells bind to ICAM-1 and VCAM-1. Additionally, certain T cell subsets bind to ELAM-1. We now report that resting CD4+ and CD8+ T cells as well as individual CD4+ T cell clones and CD8+ T cell lines bind to GMP-140 in an adhesion assay using protein chimeras consisting of the extracellular domain of GMP-140 linked to the hinge domain of human IgG1. Whereas resting T cells bound similarly to ELAM-1 IgG and GMP-140 IgG, activated T cells represented by CD4+ T cell clones and CD8+ T cell lines bound to GMP-140 IgG, but not to ELAM-1 IgG. Neither the binding to immobilized GMP-140 IgG, nor to immobilized ELAM-1 IgG could provide T cells with costimulatory signals for proliferation in the presence of submitogenic concentrations of anti-CD3 antibodies. The binding of T cells to the endothelial adhesion receptor GMP-140 might be important during the initial adhesion process of lymphocytes in rejecting grafts.


Asunto(s)
Moléculas de Adhesión Celular/fisiología , Glicoproteínas de Membrana Plaquetaria/fisiología , Linfocitos T/fisiología , Adhesión Celular , Línea Celular , Selectina E , Humanos , Inmunoglobulina G/fisiología , Activación de Linfocitos , Neuraminidasa/farmacología , Selectina-P , Proteínas Recombinantes de Fusión/biosíntesis , Molécula 1 de Adhesión Celular Vascular
13.
Transplantation ; 52(2): 280-4, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1871801

RESUMEN

It is widely believed that calcium antagonists such as diltiazem exert immunosuppressive effects in kidney graft recipients--however, the mechanism is unclear. In a randomized controlled trial, kidney graft recipients who received diltiazem during transplantation and for an average of 12 months thereafter experienced significantly fewer rejection episodes than patients treated with cyclosporine and steroids alone. Furthermore, 1-year (97% vs. 85%) and 4-year (80% vs. 70%) graft survival rates were higher in diltiazem-treated patients, but the difference was not statistically significant. In vitro, diltiazem had little immunosuppressive activity. Concentrations of diltiazem which blocked the proliferation of PHA-stimulated human peripheral blood mononuclear cells, or prevented activation-associated accumulation of interleukin-2 mRNA, or p50- and p70-IL-2 receptor mRNA exceeded pharmacological concentrations by more than 100-fold. Both, CsA and high doses of diltiazem caused an increase of IL-6 mRNA. In contrast to these findings, the IL-6 plasma concentrations were comparable in both groups, whereas the serum concentration of soluble IL-2 receptors was decreased in patients treated with diltiazem. Administration of diltiazem caused an alteration of CsA metabolism. The whole-blood concentration of CsA metabolite 17 was significantly increased in diltiazem-treated patients, resulting in a five-times-higher concentration of this metabolite in the cellular blood compartment compared with the parent drug. Changes in metabolites 1, 8, and 18 levels were less pronounced. Although direct immunosuppressive properties of diltiazem are unlikely, diltiazem could support immunosuppression by altering CsA metabolism, and promoting accumulation of certain metabolites.


Asunto(s)
Ciclosporinas/metabolismo , Diltiazem/farmacología , Trasplante de Riñón/fisiología , Adulto , Ciclosporinas/farmacología , Interacciones Farmacológicas , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Interleucina-6/sangre , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/fisiología , Activación de Linfocitos/efectos de los fármacos , Masculino , Estudios Prospectivos , Receptores de Interleucina-2/sangre
14.
Transplantation ; 69(7): 1386-91, 2000 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-10798759

RESUMEN

BACKGROUND: Cell-mediated immune responses can be down-regulated by induction of apoptosis of immunoreactive lymphocytes. In the present study, we have tested the feasibility of a strategy for immunosuppression by the selective induction of apoptosis in activated, interleukin (IL)-2 receptor-positive lymphocytes, using a triple IL-2-IgG-FasL fusion protein. The IL-2-IgG-FasL fusion protein combines IL-2 for the selection of activated T cells, with the extracellular domain of the FasL molecule for inducing T-cell apoptosis. These components were separated by the Fc part of IgG1 serving as a spacer as well as for half-life prolongation. METHODS: The gene for the chimeric protein was created by fusing DNA sequences encoding for the three functional components: human IL-2, the Fc part of human IgG1, and the extracellular domain of murine FasL. When the fusion gene was expressed in murine J558L cells, we obtained soluble dimeric immunoglobulin-like proteins in the supernatant. After analyzing the function of the IL-2 and FasL portions individually in vitro, a delayed-type hypersensitivity (DTH) reaction to sheep red blood cells as model for cell-mediated immune responses was investigated to evaluate the IL-2-IgG-FasL-mediated immunosuppression in vivo. RESULTS: In vitro, the IL-2-IgG-FasL fusion protein supported IL-2-dependent proliferation of Fas-resistant CTLL-2 cells, whereas concanavalin A-T blasts were induced to undergo apoptosis by the FasL portion. In vivo, this fusion protein potently inhibited a murine DTH. This was associated with an increased rate of apoptosis in activated lymphocytes in the spleen, even at very low doses of the fusion protein. Furthermore, a second antigen challenge 10 days after IL-2-IgG-FasL treatment still failed to elicit a DTH response. CONCLUSION: The abrogation of a standard T cell-dependent immune response in vivo demonstrates that IL-2-IgG-FasL can be successfully exploited to trigger the death of deleterious T cells, presenting a potentially useful strategy in the management of autoimmune diseases and allotransplant rejections.


Asunto(s)
Hipersensibilidad Tardía/tratamiento farmacológico , Inmunoglobulina G/genética , Terapia de Inmunosupresión/métodos , Interleucina-2/genética , Glicoproteínas de Membrana/genética , Proteínas Recombinantes de Fusión/uso terapéutico , Animales , Apoptosis , División Celular/efectos de los fármacos , Línea Celular , Proteína Ligando Fas , Estudios de Factibilidad , Humanos , Hipersensibilidad Tardía/patología , Hipersensibilidad Tardía/fisiopatología , Fragmentos Fc de Inmunoglobulinas/genética , Hígado/patología , Activación de Linfocitos , Ratones , Ovinos/sangre , Bazo/patología , Linfocitos T/efectos de los fármacos , Linfocitos T/fisiología , Timo/patología
15.
Transplantation ; 72(1): 63-9, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11468536

RESUMEN

BACKGROUND: Supplementation of immunosuppressive therapy with mycophenolate mofetil (MMF) has been found to reduce the rate of acute rejection in renal transplantation. We report a dose-finding study for MMF when administered in combination with low-dose tacrolimus and corticosteroid prophylaxis in cadaveric renal transplant recipients. METHODS: Two hundred thirty-two patients at 16 centers were enrolled in this randomized, parallel-group study. The three treatment groups were tacrolimus and corticosteroids (MMF-0 group, n=82); tacrolimus, corticosteroids, and 1 g of MMF daily (MMF-1 g group, n=79); and tacrolimus, corticosteroids, and 2 g of MMF daily (MMF-2 g group, n=71). Study duration was 6 months, and patients were followed up for patient and graft survival for 12 months. RESULTS: At 6 months posttransplantation, daily doses of 1 g and 2 g of MMF were associated with significantly lower rates of acute rejection compared with tacrolimus alone. The Kaplan-Meier rates were 48.5%, 24.9%, and 22.9%, respectively, for the three treatment groups when acute rejection was determined by clinical criteria (P=0.007). At month 12, patient survival rates were 100%, 97.5%, and 97.2% and graft survival rates were 90.2%, 92.4%, and 93.0% for the MMF-0 group, MMF-1 g group, and the MMF-2 g group, respectively. Gastrointestinal adverse events and leukopenia were higher in the MMF groups, especially in the MMF-2 g group (P<0.05). CONCLUSIONS: Low-dose tacrolimus combined with a MMF dose of 1 g daily and corticosteroids provided an optimized efficacy and safety profile. A higher dose of MMF (2 g) was associated with greater toxicity without a significant improvement in efficacy.


Asunto(s)
Inmunosupresores/administración & dosificación , Trasplante de Riñón , Ácido Micofenólico/administración & dosificación , Tacrolimus/administración & dosificación , Corticoesteroides/administración & dosificación , Corticoesteroides/efectos adversos , Corticoesteroides/uso terapéutico , Adulto , Cadáver , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Leucopenia/inducido químicamente , Masculino , Persona de Mediana Edad , Ácido Micofenólico/efectos adversos , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapéutico , Análisis de Supervivencia , Tacrolimus/efectos adversos , Tacrolimus/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento
16.
Kidney Int Suppl ; 36: S87-93, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1377295

RESUMEN

To test the hypothesis that calcium antagonists decrease the incidence and severity of delayed graft function, we conducted three separate, prospective, randomized trials. In these trials, we investigated the effects of diltiazem and those of the prostacyclin analogue iloprost. In the first study, 22 control patients and 20 diltiazem patients received grafts perfused with either vehicle or diltiazem 20 mg/liter in the Euro-Collins solution. Subsequently, the diltiazem subjects were given the drug as a bolus of 0.28 mg/kg, followed by a continuous infusion of 0.002 mg/min/kg for the following two days. Thereafter, diltiazem 60 mg was given to the treated subjects orally for up to four years. In the second study, 11 control subjects and 10 diltiazem subjects received the same postoperative regimen, but all grafts were harvested without addition of diltiazem to the perfusion solution. In the third protocol, four groups were studied as follows: 19 control subjects who received no specific treatment, 16 subjects who received diltiazem, 16 subjects who were given iloprost, and 14 subjects who received both iloprost and diltiazem. The donor kidney of treated patients was perfused with either diltiazem, iloprost, or both drugs. Primary graft function occurred more commonly in the groups receiving diltiazem. Further, in the first study the number of hemodialyses per patient was reduced in those patients with delayed graft function. Fewer rejection episodes occurred in patients receiving diltiazem. Plasma levels of soluble interleukin-2 receptors decreased significantly during diltiazem treatment. Moreover, renal biopsies showed less severe signs of Cyclosporin A (CsA) nephrotoxicity in diltiazem-treated patients compared to controls, even though these patients also exhibited higher CsA trough levels.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Lesión Renal Aguda/prevención & control , Diltiazem/farmacología , Iloprost/farmacología , Trasplante de Riñón/efectos adversos , Adulto , Creatinina/sangre , Ciclosporina/efectos adversos , Ciclosporina/antagonistas & inhibidores , Ciclosporina/metabolismo , Diltiazem/administración & dosificación , Rechazo de Injerto/efectos de los fármacos , Humanos , Iloprost/administración & dosificación , Trasplante de Riñón/patología , Trasplante de Riñón/fisiología , Persona de Mediana Edad , Estudios Prospectivos
17.
J Clin Pharmacol ; 29(3): 240-5, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2723110

RESUMEN

Reduced bioavailability (F) due to hepatic first-pass extraction of an oral dose (D) is a well-known pharmacokinetic phenomenon. An integrated solution for Michaelis-Menten kinetics of the first-pass effect is derived from the maximal metabolic rate (Vm), volume of distribution (Vd), first order absorption rate constant (ka), Michaelis constant (Km), and liver blood flow (Q). F = 1 - VmVd/kaD ln (1 + kaD/QKm) This equation for single dosage can also be extended to steady state kinetics after multiple dosing in which the amount of a drug present in the hepatic circulation is considered. According to the literature, the bioavailability of a single 80 mg oral dose of propranolol (F = 0.22) increases after multiple doses Fss = 0.36). Based on the first pass equations for single dosage and multiple dosing, the maximal metabolic rate (Vm = 0.043 mg l-1 h-1) corresponding to 310 mg per day and the Michaelis constant (Km = 0.10 mg/l) were calculated for propranolol. Incorporation of nonlinear plasma protein binding in this concept may explain the lack of threshold phenomenon for a single dose of less than 40 mg propranolol. Zero order absorption kinetics could explain why cumulation kinetics seem linear even at an excessive dosage of 960 mg propranolol per day. From these derivations it may be concluded that multiple dosing, increase in plasma protein binding, high absorption rate, and increased portal venous blood flow will increase bioavailability, whereas slow release formulations, fractional drug dosage, and saturable absorption kinetics will decrease bioavailability of first-pass drugs like propranolol.


Asunto(s)
Hígado/metabolismo , Propranolol/farmacocinética , Absorción , Administración Oral , Disponibilidad Biológica , Humanos , Cinética , Propranolol/administración & dosificación
18.
Clin Nephrol ; 31(4): 190-7, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2714023

RESUMEN

Short-term prognosis of rapidly progressive glomerulonephritis (RPGN) has improved since immunosuppressive therapy was introduced. The long-term course of the disease was investigated in 46 consecutive and unselected patients over a period of 15 years (1970-1986) with a mean observation time of five years (+/- 45 months). Most of the 46 patients had idiopathic RPGN (61%). Initially, hemodialysis needed 25 of the 46 patients (54%). Immunosuppressive therapy (plasma exchange, methylprednisolone pulses, steroids, cyclophosphamide, azathioprine) was administered in 36 of the 46 patients (78%). A remission was achieved in only 19 of the 36 patients who received immunosuppression (53%) and no spontaneous improvement was seen. Factors indicating poor prognosis were initial high serum creatinine, high percentage of crescents in glomeruli, glomerular sclerosis, and immunohistologic staining of the IgG at the tubuli. In 11 patients with remission, immunosuppression was discontinued and 6 had a relapse. Long-term immunosuppression was given to 8 patients with remission. Their renal function was not normal (creatinine 240 +/- 77 mumol/l), but none had a relapse (p = 0.01). It is concluded that the treatment of RPGN requires long-term attendance and repeated immunosuppression comparable to a systemic immune disease.


Asunto(s)
Glomerulonefritis/terapia , Terapia de Inmunosupresión , Adulto , Anciano , Azatioprina/uso terapéutico , Ciclofosfamida/uso terapéutico , Femenino , Humanos , Terapia de Inmunosupresión/efectos adversos , Terapia de Inmunosupresión/mortalidad , Masculino , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , Intercambio Plasmático , Pronóstico , Esteroides/uso terapéutico
19.
Clin Nephrol ; 54(3): 179-90, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11020015

RESUMEN

BACKGROUND: Acute interstitial nephritis has been known as a complication of mainly streptococcal infection for nearly a century. With the advent of infection control, it became a complication caused by antibiotics and later by other drugs, which might have changed the outcome. To determine risk factors for the development of chronic renal insufficiency, and thus, the transition from acute to chronic interstitial nephritis, we performed a retrospective study of all cases of acute interstitial nephritis found by reviewing 1,068 renal biopsies from 1968 to 1997. METHODS: Patients with permanent and reversible renal insufficiency after acute interstitial nephritis were compared with respect to the causative event, the symptoms, and the clinical and histological findings. Differences between the groups were calculated by applying bi- and multivariate analysis. RESULTS: Acute interstitial nephritis was found in 6.5% of all biopsies (64 patients with 68 episodes of acute interstitial nephritis); it was infection-induced in 10%, idiopathic in 4%, and drug-induced in 85% of the cases (antibiotics in 13 cases, analgesics in 17, non-steroidal anti-inflammatory drugs (NSAIDs) in 16, diuretics in 5, and various other drugs in 7). Renal insufficiency was reversible in 69% and permanent in 31% (12% partially reversible, 19% irreversible). The infection-induced and idiopathic types of acute interstitial nephritis were always reversible. Drug-related acute interstitial nephritis caused permanent renal insufficiency in 36% with a maximum of 56% in NSAID-induced cases. In drug-induced cases, intake of the suspected drug for more than a month prior to diagnosis caused permanent renal insufficiency in 88% and interstitial granuloma in 31%. Multivariate analysis disclosed the following significant features separating the permanent from the reversible renal insufficiency group: patients in the first group had more tubular atrophy in their histology, more chronic use of mixed analgesics and/or NSAIDs, less oliguria or anuria as an acute symptom, fewer antibiotics as causative agents, more interstitial granuloma, more pronounced interstitial cell infiltration in their histology, and more imaging of renal shrinkage. Renal histology had the highest predictive value. CONCLUSION: Today, acute interstitial nephritis is mainly drug-induced. NSAIDs are the most frequent cause of permanent renal insufficiency after acute interstitial nephritis. Clinically, subacute symptoms, a prolonged intake of the suspect drug, and chronic analgesic or NSAID use are related to a more chronic course of interstitial nephritis. In histology, tubular atrophy, interstitial granuloma, and pronounced interstitial cell infiltration indicate chronicity.


Asunto(s)
Nefritis Intersticial , Enfermedad Aguda , Adulto , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Nefritis Intersticial/complicaciones , Nefritis Intersticial/diagnóstico , Pronóstico , Factores de Riesgo
20.
Clin Nephrol ; 29(6): 299-306, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3396233

RESUMEN

The knowledge of some characteristic findings on the personality of patients with analgesic-associated nephropathy (AAN) may facilitate diagnosis of the disease at an early stage. We therefore investigated the 144 patients at our hemodialysis center and compared the AAN patients (33%) with those having other kidney diseases (controls). Patients with AAN were older (60 +/- 10 vs 52 +/- 15 years, p less than 0.001) and predominantly women. Acetaminophen and metamizol metabolites were detected more frequently in blood from the AAN patients than in that from the controls (25% vs 3%, p = 0.002). More AAN patients were smokers, and they more frequently complained of vague symptoms (pain, sensitivity to changes in weather, insomnia) and also more frequently requested prescriptions for analgesics, hypnotics, laxatives, stomachics and antipruritics. Because they were older, AAN patients had fewer occupational and financial problems. The compliance of the AAN patients was significantly better with respect to important dialysis parameters such as weight gain between dialysis treatments (3.6 +/- 1.3 vs 4.0 +/- 1.3% body weight, p less than 0.05) and diastolic blood pressure (81 +/- 12 vs 86 +/- 12 mmHg, p = 0.025). Despite an older age and higher morbidity, the cumulative 17-year survival rate of the AAN patients did not differ from that of the controls. We conclude that AAN patients have characteristic personality traits. Their better compliance, adjustment to the hemodialysis situation and social conditions are responsible for their good survival on hemodialysis.


Asunto(s)
Acetaminofén/efectos adversos , Enfermedades Renales/inducido químicamente , Personalidad , Diálisis Renal , Adaptación Psicológica , Factores de Edad , Femenino , Humanos , Enfermedades Renales/mortalidad , Enfermedades Renales/psicología , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Pronóstico , Fumar , Factores Socioeconómicos
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