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1.
Photodiagnosis Photodyn Ther ; 19: 194-201, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28578124

RESUMEN

BACKGROUND: Photodynamic therapy (PDT) represents a palliative treatment option for a selected group of patients with head and neck squamous cell carcinoma (HNSCC). PDT induces a local inflammatory reaction with the potential to initiate antitumor immune responses. However, the systemic impact on peripheral immune cells has not been described so far. METHODS: HNSCC patients (n=9) were treated with PDT in a palliative setting. All patients had previously undergone several oncologic treatment regimens. Blood samples were taken before, during and after PDT. Age-matched healthy donors served as control group (NC, n=15). The frequency and absolute number of T- and B-lymphocytes, CD4+CD39+ regulatory T-cells (Treg) and NK-cells were measured by 10-color flow cytometry. Serum concentrations of T cell related cytokine panel, including HMGB1, IL-6, IL-10 and perforin were measured by bead array and ELISA. RESULTS: In heavily pretreated HNSCC patients, the number and frequency of Treg and NK-cells were increased as compared to NC. PDT induced a further increase of the frequency of Treg and NK-cells in the peripheral blood. Additionally, the serum concentrations of HMGB1, IL-6 and IL-10 showed a significant elevation after treatment with simultaneously decreased perforin levels. CONCLUSION: Although PDT is a local treatment regimen, a systemic inflammatory response with altered peripheral immune cell populations and cytokine concentrations is visible. The increased Treg and NK cell numbers after PDT support the hypothesis that PDT may successfully be combined with NK cell or T cell activating immune checkpoint modulators in HNSCC patients to improve HNSCC specific immunity.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Citocinas/metabolismo , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Leucocitos Mononucleares/efectos de los fármacos , Fotoquimioterapia/métodos , Adulto , Anciano , Femenino , Citometría de Flujo , Proteína HMGB1/efectos de los fármacos , Humanos , Mediadores de Inflamación/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Masculino , Persona de Mediana Edad , Perforina/biosíntesis , Carcinoma de Células Escamosas de Cabeza y Cuello , Linfocitos T Reguladores/efectos de los fármacos
2.
Eur Radiol ; 11(12): 2488-95, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11734946

RESUMEN

The aim of this study was to investigate the value of a contrast-enhanced 3D MR angiography in detecting postoperative vascular complications after kidney transplantation in comparison with digital subtraction angiography (DSA). Forty-one patients who underwent a kidney transplantation were examined with MR angiography and DSA. Contrast-enhanced MR angiography was performed as a dynamic measurement with one precontrast and three postcontrast measurements. Maximum intensity projection reconstructions were performed for all postcontrast data sets after DSA. The results were evaluated by two independent observers who were unaware of the DSA results. Twenty-three hemodynamically significant arterial stenoses were identified with DSA in the iliac arteries ( n=7), the renal allograft arteries ( n=12), and in their first branches ( n=4). For a patient-based analysis the sensitivity and specificity, respectively, for observer 1 were 100 and 97%, and for observer 2, 100 and 93%. Respective data were 100 and 100% after a consensus evaluation by two observers. Complications involving the renal veins were detected in 2 cases and perfusion defects of the kidney parenchyma were detected in 4 cases. Contrast-enhanced MR angiography is a reliable method in identifying postoperative arterial stenoses after kidney transplantation. In addition, dynamic MR angiography can be helpful in detecting venous complications and perfusion defects in kidney allografts.


Asunto(s)
Arteriopatías Oclusivas/diagnóstico , Arteria Ilíaca , Aumento de la Imagen , Imagenología Tridimensional , Trasplante de Riñón , Angiografía por Resonancia Magnética , Complicaciones Posoperatorias/diagnóstico , Obstrucción de la Arteria Renal/diagnóstico , Adulto , Angiografía de Substracción Digital , Femenino , Humanos , Arteria Ilíaca/patología , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Arteria Renal/patología , Sensibilidad y Especificidad
4.
Fortschr Med Orig ; 118(4): 135-9, 2001 Jan 11.
Artículo en Alemán | MEDLINE | ID: mdl-11217676

RESUMEN

Renal Transplantation is hampered worldwide by the continuing lack of cadaveric organs. The discrepancy between the number of patients on the waiting list and the number of organs available is further compounded by the still unresolved problem of chronic transplant failure. Against this background, the arguments for increasing acceptance of the use of kidneys from living donors, both related and unrelated, are discussed. Initial reports on appreciably improved transplant survival rates of organs from unrelated living donors (85% survival after 3 years [19]) have since been confirmed by more recent studies. Our own results, in part obtained during a prospective study involving 103 patients (53 related, 50 unrelated) done between October 1994 and April 1999, with strict psychological care/evaluation prior to and after transplantation, revealed a four-year transplant survival rate of 98% in both groups. So far, the higher rejection rate of 34% in unrelated, vs. 13.2% in related, donors has not led to any earlier chronic dysfunction of the transplant. The expanded use of living kidney donors is not only ethically justifiable, but also improves the outcome.


Asunto(s)
Ética Médica , Rechazo de Injerto/epidemiología , Trasplante de Riñón/estadística & datos numéricos , Donadores Vivos/estadística & datos numéricos , Alemania , Rechazo de Injerto/prevención & control , Humanos , Pronóstico , Supervivencia Tisular
5.
Transpl Int ; 13 Suppl 1: S354-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11112031

RESUMEN

This study was designed to investigate whether the introduction of ganciclovir to clinical use for anti-CMV treatment changes the risk of CMV infection in renal transplant patients. A total of 1545 cases who had received cadaveric renal transplants were divided into two groups: group 1 (n = 721) was made up of patients who received their transplants within 6 years before the introduction (1991) of ganciclovir and group 2 (n = 824), of individuals transplanted thereafter. Patient and graft survival of CMV D+/R- patients was uni- and multivariately compared with non-CMV D+/R- patients. In CMV D+/R- patients in group 1, survival was significantly lower, and their relative risk for graft loss was 1.32-fold (P = 0.0483) that of non-CMV D+/R- patients. In group 2 patient and graft survival was identical regardless of whether the patients were at risk for CMV infection or not. The risk of CMV infection can be eliminated by hyperimmunoglobulin prophylaxis, CMV monitoring and preemptive ganciclovir treatment in renal transplant patients.


Asunto(s)
Antivirales/uso terapéutico , Infecciones por Citomegalovirus/prevención & control , Ganciclovir/uso terapéutico , Supervivencia de Injerto , Trasplante de Riñón/fisiología , Complicaciones Posoperatorias/prevención & control , Adulto , Análisis de Varianza , Femenino , Humanos , Trasplante de Riñón/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo , Trasplante Homólogo
7.
Transplantation ; 69(4): 677-9, 2000 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-10708132

RESUMEN

BACKGROUND: A recent review of the Cincinnati Transplant Tumor Registry recorded 24 de novo renal cell carcinomas developing in renal allografts. However, late development of these tumors after transplantation is very rare. Only four reports exist regarding conservative surgery on kidney transplant tumors. METHODS: This is a report on a case of a large 6-cm de novo renal cell carcinoma in a 10-year-old transplanted kidney. Optimal therapy by transplant nephrectomy or tumor enucleation was discussed. RESULTS: Partial resections or enucleations of renal cell carcinoma are still less than ideal in carcinomas larger than 3 cm considering the higher risk of local recurrence. But the recipient in this case had done so well and had had such a high quality of life after transplantation that partial nephrectomy as therapy of choice was selected. Now the patient is 2 years tumor free. CONCLUSION: The case report demonstrates that in certain select cases of large tumors, organ-preserving surgery could be an alternative approach in combining complete tumor removal with preservation of graft function.


Asunto(s)
Carcinoma de Células Renales/etiología , Neoplasias Renales/etiología , Trasplante de Riñón/efectos adversos , Anciano , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/cirugía , Femenino , Humanos , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Trasplante de Riñón/diagnóstico por imagen , Trasplante de Riñón/patología , Recurrencia Local de Neoplasia/epidemiología , Factores de Riesgo , Ultrasonografía
10.
Rofo ; 171(4): 313-8, 1999 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-10598168

RESUMEN

PURPOSE: To compare Gadolinium-enhanced MR angiography with conventional DSA in the preoperative evaluation of living kidney donors. MATERIAL AND METHODS: 27 potential living kidney donors were examined with contrast-enhanced MR angiography after conventional angiography. The MR angiograms were evaluated for the number of renal arteries, the presence of early arterial branching and vascular pathologies by two independent readers. The results were compared with those of selective conventional angiography and intraoperative findings. RESULTS: Conventional angiography detected 14 accessory renal arteries. Reader A detected 13 of 14 accessory arteries with no false positive result (sensitivity 93%, specificity 100%). Reader B detected 11 of 14 accessory vessels with one false positive finding (sensitivity 79%, specificity 98%). Early arterial branching was detected by both readers in 9 of 12 vessels with no false positive result (sensitivity 75%, specificity 100%). None of the patients had additional vascular pathology. DISCUSSION: Gadolinium-enhanced MR angiography is a non-invasive alternative to conventional angiography in the preoperative evaluation of living kidney donors. In order to achieve high accuracy in detecting accessory renal arteries and early arterial branching extensive experience with the method and the specific preoperative needs is required. Selective conventional angiography is still superior in detecting very small accessory vessels and early arterial branching.


Asunto(s)
Angiografía de Substracción Digital , Trasplante de Riñón , Riñón/anatomía & histología , Angiografía por Resonancia Magnética , Arteria Renal/anatomía & histología , Donantes de Tejidos , Adulto , Anciano , Medios de Contraste , Estudios de Evaluación como Asunto , Femenino , Gadolinio DTPA , Humanos , Aumento de la Imagen , Riñón/irrigación sanguínea , Riñón/diagnóstico por imagen , Riñón/patología , Masculino , Persona de Mediana Edad , Arteria Renal/diagnóstico por imagen , Arteria Renal/patología , Sensibilidad y Especificidad
11.
Transpl Int ; 11 Suppl 1: S86-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9664951

RESUMEN

The detrimental effect of acute rejection episodes on long-term outcome of renal allografts in cyclosporin-treated patients is well established, although has not been seen by all investigators. To analyse the possibility that aggressive treatment of the first episode may ameliorate this detrimental effect, we performed an open label, randomised prospective trial in cyclosporin-based, immunosuppressed recipients of postmortem renal allografts in order to compare two different treatment protocols during primary acute rejection episodes: (1) group 1 of 25 patients received 3 x 250 mg methylprednisolone (MP) i.v.; (2) group 2 of 25 patients received 7 x anti-thymocyte globulin (ATG)-Fresenius i.v. (4 mg/kg body weight). During a period of 4 years, the following clinical observations were made: (1) The incidence of an acute re-rejection episode was significantly reduced in the ATG-treated study group (16%) compared to the MP-treated study group (72%); (2) The severity of the first acute rejection episode (intensity of renal dysfunction measured in terms of 10-day creatinine area under curve) showed no significant difference between the groups (37 mg x 10-d/dl to 58 mg x 10-d/dl); and (3) The half-lives of allografts in both groups have not shown any significant differences so far. In conclusion, aggressive treatment of the first rejection episode of renal allografts with the use of ATG reduced the incidence of re-rejection episodes which, however, are not reflected so far by improvement of the 4-year survival rate of these allografts. Since it could be observed that re-rejection is an even worse predictor for chronic transplant failure, a better long-term outcome of renal allografts in ATG-treated patients may be expected during a longer observation period. The incidence of a third episode was also reduced in the ATG-treated group (0%) compared to the MP-treated group (12%).


Asunto(s)
Rechazo de Injerto/tratamiento farmacológico , Inmunoglobulinas Intravenosas/uso terapéutico , Trasplante de Riñón , Adulto , Ciclosporina/uso terapéutico , Humanos , Linfocitos/inmunología , Estudios Prospectivos
12.
Transpl Int ; 9 Suppl 1: S479-82, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8959891

RESUMEN

In the present study, levels of free oxygen radicals, generated in the very early period of reperfusion during human kidney transplantation, were assessed by determination of malondialdehyde (MDA) levels using a high-pressure liquid chromatography (HPLC) method. Renal blood samples were obtained during reperfusion by intraoperative cannulation of the renal vein. Simultaneously, systemic MDA levels were determined. Furthermore, local and systemic levels of interleukin 6 (IL-6), tumor necrosis factor (TNF) receptors, p55 and p75, and vitamin E were measured. In a second group of patients, 500 mg of ascorbic acid were given prior to reperfusion. Renal MDA levels in the control group were always higher compared to systemic levels. IL-6 showed a marked increase shortly after reperfusion in the renal blood. In the scavenger group there was a diminution of these effects. TNF receptor levels and vitamin E remained largely unchanged. The results of this pilot study demonstrated clinically the moderate production of reactive oxygen species and the liberation of IL-6 shortly after reperfusion of human transplanted kidneys. Furthermore, the modulating effect of a radical scavenger on these effects was shown.


Asunto(s)
Depuradores de Radicales Libres/farmacología , Trasplante de Riñón , Oxígeno/metabolismo , Adulto , Ácido Ascórbico/farmacología , Femenino , Radicales Libres , Humanos , Interleucina-6/análisis , Peroxidación de Lípido , Masculino , Malondialdehído/análisis , Persona de Mediana Edad
14.
Biochim Biophys Acta ; 1252(1): 103-13, 1995 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-7548152

RESUMEN

Although 13 lysines of horse cytochrome c are invariant, and three more are extremely conserved, the modification of their side-chain epsilon-amino groups by beta-thiopropionylation caused important changes in protein properties for only three of them; lysines 72,73 and 79. Optical spectroscopy, electron and nuclear paramagnetic resonance, electron spin echo envelope modulation, and molecular weight studies, as well as the unique features of their reaction with cytochrome-c oxidase, indicate that in the oxidized state the modification of these lysines resulted in equilibria between two different states of iron ligation: the native state, in which the metal is coordinated by the methionine-80 sulfur, and a new state in which this ligand is displaced by the sulfhydryl groups of the elongated side chains. The reduction potentials of the TP Lys-72 and the TP Lys-79 derivatives were 201 and 196 millivolt, respectively, indicating that the equilibria favored the sulfhydryl ligated state by 1.5 and 1.7 kcal/mol, respectively. In the ferric state, the protein modified at lysine 72 remained stable as a monomer, but that modified at lysine 73 dimerized rapidly through disulfide bond formation, while the TP Lys-79 cytochrome c dimerized with a half-time of approx. 3 h, both recovering the native-like iron ligation. By contrast, in the ferrous state the monomeric state and the native ligation were preserved in all cases, indicating that the affinity of the cytochrome-c ferrous iron for the methionine-80 sulfur is particularly strong. The dimerized derivatives lost most, but not all, of the capability of the native protein for electron transfer from ascorbate-TMPD to cytochrome-c oxidase.


Asunto(s)
Grupo Citocromo c/química , Hemo/química , Hierro/química , Lisina/química , Animales , Espectroscopía de Resonancia por Spin del Electrón , Caballos , Espectroscopía de Resonancia Magnética , Oxidación-Reducción , Espectrofotometría , Compuestos de Sulfhidrilo , Tetrametilfenilendiamina
15.
Biochim Biophys Acta ; 1252(1): 114-25, 1995 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-7548153

RESUMEN

beta-Thiopropionyl derivatives of horse cytochrome c singly modified at each of 18 different lysine epsilon-amino groups have been prepared using sulfosuccinimidyl-2-(biotinamido)ethyl-1,3-dithiopropionate and purified to homogeneity by high-pressure liquid chromatography. These derivatives were characterized by determination of: (i) the location of the modification; (ii) reduction potentials; (iii) visible and NMR spectra: and by (iv) measurement of electron transfer activity with cytochrome-c oxidase. No significant changes in structure were indicated, except for the ferric forms of the derivatives modified at lysines 72, 73, and 79 which are discussed separately. The electron transfer activity of the beta-thiopropionyl cytochromes c with bovine heart cytochrome-c oxidase was decreased to extents dependent on the position of the modification. Aminoethylation, a secondary modification which reverses the charge change, restored the electron transfer rate to that observed with the unmodified cytochrome c, irrespective of the location of the primary modification. These results afford a direct experimental demonstration that alterations in kinetics with physiological electron transfer partners resulting from modifications which cause a change of the charge of surface side chains are solely due to the electrostatic effects. Of the many chemically modified cytochromes c prepared to date, the singly substituted beta-thiopropionyl cytochromes c are likely to be particularly useful as the thiol allows covalent linkage of any sulfhydryl-reactive reagent to a well-defined location on the protein surface by a simple procedure, even when the secondary modifier is relatively unstable, a crucial advantage not otherwise readily achieved.


Asunto(s)
Grupo Citocromo c/química , Grupo Citocromo c/síntesis química , Lisina/química , Secuencia de Aminoácidos , Animales , Compuestos Bicíclicos con Puentes , Bovinos , Cromatografía Líquida de Alta Presión , Grupo Citocromo c/aislamiento & purificación , Complejo IV de Transporte de Electrones/química , Caballos , Espectroscopía de Resonancia Magnética , Metionina/química , Datos de Secuencia Molecular , Espectrofotometría Ultravioleta
16.
J Lipid Res ; 36(6): 1211-26, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7665999

RESUMEN

Immunocytochemistry was used to determine the intracellular location of perilipins in adipocytes and the occurrence of these proteins in tissues involved in triacylglycerol metabolism. Confocal microscopy and 3-dimensional analysis of 3T3-L1 adipocytes showed that perilipin immunofluorescence, present on the surfaces of all sized lipid droplets, appeared unevenly dispersed on the surfaces of many large lipid droplets. Electron microscopy revealed that immunogold staining for perilipin was located directly on the surface layer apposed to and surrounding the core triacylglycerol of intracellular lipid droplets of adipocytes in culture or from white and brown adipose tissue. Freeze-fracture electron microscopy indicated that the hydrophobic face of this surface monolayer contained particles identical in size and distribution to intramembranous particles (IMPs), which are unique structural features of the hydrophobic faces of bilayered membranes. Also, freeze-fracture replicas revealed areas of continuity between the surface layer of lipid droplets and the membrane leaflets of endoplasmic reticulum, suggesting that the droplet monolayer surface is an area of endoplasmic reticulum membrane leaflet modified by its unique content of perilipin. Microperoxisomes, identified by immunostaining for catalase, were found closely associated with lipid droplets, but external to and not in contact with the lipid droplet surface layer. Vimentin, identified by immunofluorescence, was present around the periphery of most lipid droplets in 3T3-L1 cells during early stages of adipocyte development but, in contrast to perilipins, vimentin was not around the periphery of many large lipid droplets in mature cells. Although perilipin was at the surface of lipid droplets in adipocytes of lactating mammary gland, none was found to be associated with the milk lipid droplets in alveolar epithelial cells, nor was the protein found on the surfaces of lipid droplets in hepatocytes. Studies in mammary gland show that perilipin immunostaining will be a valuable tool for the identification of tissue adipocytes severely depleted of their triacylglycerol stores and thus without their characteristic spherical shape. Perilipin's singular location on the surface monolayer of intracellular lipid droplets supports an intimate role for the protein in the triacylglycerol metabolic functions of adipocytes.


Asunto(s)
Adipocitos/química , Adipocitos/ultraestructura , Lípidos/análisis , Fosfoproteínas/análisis , Células 3T3 , Tejido Adiposo Pardo/ultraestructura , Animales , Proteínas Portadoras , Células Cultivadas , Retículo Endoplásmico/química , Epidídimo/ultraestructura , Femenino , Técnica del Anticuerpo Fluorescente , Técnica de Fractura por Congelación , Humanos , Lactancia , Hígado/química , Hígado/ultraestructura , Masculino , Glándulas Mamarias Animales/química , Glándulas Mamarias Animales/ultraestructura , Ratones , Microcuerpos/química , Microscopía Confocal , Microscopía Electrónica , Perilipina-1 , Ratas , Ratas Sprague-Dawley , Vimentina/análisis
17.
Urologe A ; 33(4): 303-7, 1994 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-7941177

RESUMEN

Six patients with upper urinary tract tumors were treated in our department with the Nd:-YAG laser between 1989 and 1993. The average follow-up was 23.8 months. The mean age of the patients was 65.7 years. The patients were selected for organ-conserving treatment because of bilateral synchronous tumors (2 cases), a solitary renal unit (2 cases), renal insufficiency with high surgical risk (1 case) and high surgical risk alone (1 case). Two patients were treated with open tumor excision and laser, two patients with ureteroscopic and percutaneous procedures one patient with percutaneous treatment and one patient with ureteroscopy. Two patients underwent nephroureterectomy; one of them died of metastatic bladder cancer 9 months later. Local relapses were observed in one patient who had been treated endoscopically. In a follow-up period of 6-36 months there were three patients who had no relapses. Three patients received intracavitary therapy. Kidney conserving procedures with the Nd:-YAG laser in patients with upper urinary tract tumors should be reserved for highly selected cases.


Asunto(s)
Carcinoma de Células Transicionales/cirugía , Neoplasias Renales/cirugía , Terapia por Láser/instrumentación , Neoplasias Ureterales/cirugía , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/patología , Estudios de Seguimiento , Humanos , Neoplasias Renales/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Nefrectomía , Reoperación , Neoplasias Ureterales/patología
19.
Biochem Cell Biol ; 70(7): 539-47, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1333234

RESUMEN

Seven cytochromes c, in which individual lysines have been modified to the propylthiobimane derivatives, have been prepared. These derivatives were also converted to the porphyrin cytochromes c by treatment with HF. The properties of both types of modified proteins were studied in their reactions with cytochrome c oxidase. The results show that lysines 25, 27, 60, 72, and 87 do not contribute a full charge to the binding interaction with the oxidase. These five residues, with the exception of the lysine-60 derivative, on the front surface of the protein and contain the solvent-accessible edge of the heme prosthetic group. By contrast, lysines 8 and 13 at the top of the front surface do contribute a full charge to the binding interaction with the oxidase. The removal of the positive charge on any one lysine weakens the binding to cytochrome c oxidase by at least 1 kcal (1 cal = 4.1868 J). The presence of bimane at lysines 13 and 87 clearly forces the separation of the cytochrome c and oxidase, but this does not occur with the other complexes. The bimane-modified lysine-13 protein, and to a lesser extent that modified at lysine 8, show the interesting effect of enhanced complex formation with cytochrome c oxidase when subjected to pressure, possibly because of entrapment of water at the newly created interface of the complex. Our observations indicate that the two proteins of the cytochrome c - cytochrome oxidase complex have preferred, but not obligatory, spatial orientations and that interaction occurs without either protein losing significant portions of its hydration shell.


Asunto(s)
Grupo Citocromo c/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Animales , Bovinos , Fenómenos Químicos , Química Física , Grupo Citocromo c/genética , Transporte de Electrón , Caballos , Presión Hidrostática , Mutagénesis Sitio-Dirigida , Concentración Osmolar , Especificidad por Sustrato
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