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1.
J Am Chem Soc ; 146(30): 20577-20583, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38968342

RESUMO

Lanthanides are widely assumed not to form covalent bonds due to the localized nature of their 4f valence electrons. This work demonstrates that the ionic bond of Sm(II) with cyclononatetraenyl (η9-C9H9-) in [Sm(η9-C9H9)2] can be modulated and becomes more covalent by photon-induced transfer of Sm 4f electrons to Sm 5d orbitals. This photon-induced change in bonding properties facilitates a subsequent reconfiguration of [Sm(η9-C9H9)2]. As a result, Sm-C bond length contraction is detected and the local Sm coordination environment exhibits more extensive disorder. Both Sm 4f and 5d electrons have increased participation in covalent Sm-ligand interactions. The Sm L3-edge valence band resonant inelastic X-ray scattering (VB-RIXS), high-resolution X-ray absorption near-edge structure (HR-XANES), and quantum chemical computations showcase a spectroscopic methodology for in-depth studies of bond covalency of lanthanide atoms.

2.
Am J Transplant ; 13(1): 130-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23016801

RESUMO

The impact of vesicoureteral reflux (VUR) on renal allograft outcomes is debatable, with small cohort studies reporting controversial results. The objective of this retrospective study was to evaluate long-term clinical effects of early VUR in a large cohort of kidney transplant patients. Posttransplantation voiding cystourethrography was used to evaluate 646 consecutive kidney transplant recipients before discharge. The study endpoints included VUR grade, death-censored graft or patient survival, renal function, proteinuria and occurrence of urinary tract infections (UTIs). Of the 646 recipients, 263 (40.7%) were diagnosed with VUR. VUR grade II was most common (19.8%), followed by grades III (10.2%), I (7.9%) and IV (2.8%). VUR was less common in transplantations performed by experienced compared to inexperienced surgeons (36% vs. 48%; p = 0.004). VUR did not affect death-censored graft or patient survival and was not associated with proteinuria or occurrence of UTIs. Patients with VUR had a lower eGFR at 1 year after transplantation than did patients without VUR (60 vs. 52 mL/min/1.73 m(2) ; p = 0.02), although this difference was not observed at 3 and 5 years after transplantation. We conclude that early VUR, a common finding among renal transplant patients, may not have a meaningful impact on long-term transplant outcomes.


Assuntos
Transplante de Rim , Micção , Urografia/métodos , Refluxo Vesicoureteral/complicações , Adulto , Feminino , Humanos , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Proteinúria/etiologia , Proteinúria/prevenção & controle , Infecções Urinárias/etiologia , Infecções Urinárias/prevenção & controle
3.
Clin Transplant ; 23(3): 361-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19191813

RESUMO

BACKGROUND: Strictures and concrements are the most common biliary complications following liver transplantation. Endoscopic treatment might not lead to a definitive cure in all patients, especially in strictures involving the biliary bifurcation. The aim of this study was to determine the efficacy and the long-term outcome of hepaticojejunostomy (HJS) for post-transplant biliary tract obstruction. MATERIAL AND METHODS: Thirty-seven patients were retrospectively studied for resolving of cholestasis and the incidence of recurring biliary obstruction. RESULTS: Surgery was performed because of anastomotic strictures in 11, ischemic strictures at the donor common bile duct in seven, strictures involving the bile duct bifurcation in 10, hepatolithiasis without strictures in one and biliary cast formation diagnosed by endoscopic retrograde cholangiography or T-tube cholangiography in eight patients. Cholestasis instantly improved in 82% of the patients. After a long-term follow-up of median 33 months (range 3-149), 28 of the patients (76%) required no further intervention for recurring biliary obstruction following HJS. Anastomotic strictures were observed in six (16%), recurring biliary concrements in two patients (5%). CONCLUSION: HJS did prevent recurrent biliary obstruction in the majority of the patients. We therefore recommend early HJS for complicated post-transplant biliary tract obstruction not treatable by a limited number of endoscopic interventions.


Assuntos
Doenças Biliares/cirurgia , Ducto Hepático Comum/cirurgia , Jejuno/cirurgia , Transplante de Fígado/efeitos adversos , Adulto , Idoso , Anastomose Cirúrgica , Doenças Biliares/etiologia , Coledocostomia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Prevenção Secundária , Adulto Jovem
4.
Rev Sci Instrum ; 88(11): 113113, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29195371

RESUMO

CAT-ACT-the hard X-ray beamline for CATalysis and ACTinide/radionuclide research at the KIT synchrotron radiation facility ANKA-is dedicated to X-ray spectroscopy, including "flux hungry" photon-in/photon-out and correlative techniques and combines state-of-the-art optics with a unique infrastructure for radionuclide and catalysis research. Measurements can be performed at photon energies varying between 3.4 keV and 55 keV, thus encompassing the actinide M- and L-edge or potassium K-edge up to the K-edges of the lanthanide series such as cerium. Well-established X-ray absorption fine structure spectroscopy in transmission and fluorescence detection modes is available in combination with high energy-resolution X-ray emission spectroscopy or X-ray diffraction techniques. The modular beamline design with two alternately operated in-line experimental stations enables sufficient flexibility to adapt sample environments and detection systems to many scientific challenges. The ACT experimental station focuses on various aspects of nuclear waste disposal within the mission of the Helmholtz association to contribute to the solution of one of the greatest scientific and social challenges of our time-the safe disposal of heat producing, highly radioactive waste forms from nuclear energy production. It augments present capabilities at the INE-Beamline by increasing the flux and extending the energy range into the hard X-ray regime. The CAT experimental station focuses on catalytic materials, e.g., for energy-related and exhaust gas catalysis. Characterization of catalytically active materials under realistic reaction conditions and the development of in situ and operando cells for sample environments close to industrial reactors are essential aspects at CAT.

5.
Transplant Proc ; 47(8): 2446-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26518948

RESUMO

BACKGROUND: Selective interleukin-2 receptor (IL2R) blockade is one option to decrease acute rejection rates in kidney transplant recipients. However, there are little data on the impact of basiliximab in a triple immunosuppressive regimen (tacrolimus, mycophenolate mofetil, and low-dose steroids). Thus, this analysis aims at investigating the impact of basiliximab induction on rejection rates and immediate graft function following kidney transplantation. METHODS: Basiliximab was introduced in our center according to our center's policy in the beginning of 2011. Patients who received basiliximab (n = 83) were compared with patients without induction therapy (n = 65) transplanted before the introduction of IL2R antibody induction. RESULTS: The use of basiliximab as induction therapy decreased the incidence of biopsy-proven acute rejection (BPAR) within the 1st year after transplantation (21.5% vs 14.5%; P = .283). Overall rejection episodes (including BPAR and borderline rejection) were significantly reduced in patients with basiliximab compared with patients without (41.5% vs 24.1%; P = .033). However, graft function (incidence of delayed graft function, primary nonfunction, slow graft function, and serum creatinine decline) and overall outcome (patient and graft survivals) were similar in both groups. CONCLUSIONS: We found a favorable impact of basiliximab induction therapy on early acute rejection rate. The impact on long-term outcome must be addressed in further randomized controlled trials.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Imunossupressores/uso terapêutico , Imunoterapia , Falência Renal Crônica/cirurgia , Transplante de Rim , Proteínas Recombinantes de Fusão/uso terapêutico , Adulto , Idoso , Basiliximab , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Estudos Retrospectivos , Esteroides/uso terapêutico , Tacrolimo/uso terapêutico
6.
Sci Total Environ ; 505: 952-61, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25461096

RESUMO

The concentration, distribution, and speciation of selenium in different parts of wheat and Indian mustard, grown in a seleniferous area in Punjab, were investigated using synchrotron based (XAS) and classical acid digestion and extraction methods. The analyses revealed a high Se enrichment in all investigated plant parts, with Se levels in the range of 133-931 mg/kg (dry weight, dw). Such high Se enrichment is mainly due to the considerable amounts of easily available Se detected in the soil, which are renewed on a yearly basis to some extent via irrigation. Speciation analysis in soil and plants indicated selenate and organic Se as major Se species taken up by plants, with a minor presence of selenite. The analyses also revealed that the highest Se enrichment occurs in the upper plant parts, in agreement with the high uptake rate and mobility of selenate within plants. In both wheat and mustard, highest Se enrichments were found in leaves (387 mg/kg·dw in wheat and 931 mg/kg·dw in mustard). Organic species (dimethylselenide and methylselenocysteine) were found in different parts of both plants, indicating that an active detoxification response to the high Se uptake is taking place through methylation and/or volatilization. The high proportion of selenate in wheat and mustard leaves (47% and 70%, respectively) is the result of the inability of the plant metabolism to completely transform selenate to non-toxic organic forms, if oversupplied. Methylselenocysteine, a common Se species in accumulating plants, was detected in wheat, suggesting that, in the presence of high Se concentration, this plant develops similar response mechanisms to accumulator plants.


Assuntos
Mostardeira/química , Compostos de Selênio/análise , Poluentes do Solo/análise , Triticum/química , Biodegradação Ambiental , Índia , Selênio/análise , Solo/química
7.
Transplantation ; 59(11): 1542-9, 1995 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7778169

RESUMO

Immediately after hepatic reperfusion in human orthotopic liver transplantation, high amounts of arginase are released from the graft, thereby influencing nitric oxide metabolism. This metabolic alteration may be one component of the ischemia-reperfusion syndrome in OLT with its hemodynamic disturbances (e.g., systemic hypotension, pulmonary hypertension). The aim of this study was to compare hemodynamic and metabolic changes following OLT in the pigs with those obtained under arginase infusions in catheterized, anesthetized pigs. Following liver revascularization in the pigs, plasma arginase concentrations increased from 48 +/- 19 IU/L to 2613 +/- 944 IU/L, resulting in a drop in plasma levels of L-arginine (-87%) and in a drop in nitrite (-82%) and nitrate (-53%) concentrations. Of the measured organ-specific hemodynamic alterations, the mean pulmonary arterial pressure increased from 17 +/- 2 mmHg to 30 +/- 5 mmHg, whereas the flow/pressure index of the portal vein decreased about 60%. A primed continuous infusion of arginase (25,000 IU) increased plasma arginase levels to a maximum of 3,690 +/- 962 IU and evoked a decrease of L-arginine, but did not alter plasma nitrite or nitrate levels. The administration of arginase in healthy pigs did not influence cardiac output, mean arterial pressure, heart rate, or total peripheral resistance, but led to an increase of mean pulmonary arterial pressure from 19 +/- 3 to 48 +/- 5 mmHg and to a reduction of arterial hepatic blood flow from 229 +/- 65 ml/min to 154 +/- 41 ml/min. From this we conclude that high levels of liver arginase cause hemodynamic alterations in the lung and the liver. We hypothesize that the pulmonary hypertension and the reduced hepatic blood flow found during the immediate reperfusion period after OLT are possibly related to the increased arginase release due to the hepatic damage of the graft.


Assuntos
Arginase/sangue , Hemodinâmica/fisiologia , Transplante de Fígado/fisiologia , Fígado/enzimologia , Traumatismo por Reperfusão/enzimologia , Animais , Arginase/administração & dosagem , Feminino , Hemodinâmica/efeitos dos fármacos , Infusões Intravenosas , Masculino , Traumatismo por Reperfusão/fisiopatologia , Suínos
8.
Transplantation ; 52(2): 302-6, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1871803

RESUMO

The course of endotoxemia, TNF alpha, and IL-6 during orthotopic liver transplantation was studied in 28 transplantations performed in 27 patients to evaluate their impact on early postoperative rejection and infection. The preoperative levels of endotoxin, TNF alpha, and IL-6 were not different in patients who did or did not develop postoperative rejection and/or infection within the first 10 postoperative days. At the end of surgery, TNF alpha levels increased in patients who developed rejection (median 100 pg/ml vs. 11.5 pg/ml, P = 0.004). A TNF alpha level of greater than 100 pg/ml at the end of transplantation predicted rejection in 82% of the patients. During surgery, IL-6 levels increased significantly in patients with subsequent postoperative infection, reaching significance after revascularization of the graft (median 975 pg/ml vs. 185 pg/ml, P = 0.006). An IL-6 cutoff level of 800 pg/ml predicted postoperative infection in 75% of the patients. Endotoxins were elevated intraoperatively in patients with postoperative infection, but the difference did not reach significance. There was no prognostic relevance with respect to the intraoperative values of TNF alpha and infection or IL-6 values and rejection. An intraoperative elevation of TNF alpha seems to precede early postoperative rejection, and highly increased IL-6 may be a predictor of subsequent infection in human liver transplantation.


Assuntos
Endotoxinas/sangue , Rejeição de Enxerto/fisiologia , Interleucina-6/metabolismo , Complicações Intraoperatórias/sangue , Transplante de Fígado/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Feminino , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/sangue
9.
Transplantation ; 67(9): 1231-5, 1999 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10342314

RESUMO

Early diagnosis and monitoring of an alcohol relapse in patients after orthotopic liver transplantation for alcoholic cirrhosis is of importance for the long-term outcome. A prospective study of 97 patients who underwent orthotopic liver transplant for alcoholic cirrhosis has been performed. All of the recipients considered for analysis survived for at least 3 months and were under the care of one specialist psychologist. Mean follow-up amounted to 48.5+/-1.4 months. The rates of alcohol relapse at 1 and 3 years after orthotopic liver transplant were 6 and 9%, respectively. Carbohydrate-deficient transferrin is a biological marker for alcohol abuse independently of liver disease and has been used for the first time ever in liver graft recipients. A total of 830 values were included prospectively in the study population. Detection of alcohol relapse had a sensitivity of 92% and a specificity of 98%. Changes in carbohydrate-deficient transferrin levels indicated clandestine and sporadic drinking after transplantation. Furthermore, clinical events were not found to influence carbohydrate-deficient transferrin, either in patients with or without alcoholic relapse. In our opinion, carbohydrate-deficient transferrin is a useful screening marker for alcohol relapse in patients after orthotopic liver transplant for alcoholic cirrhosis, to select those patients who need special attention from the psychologist.


Assuntos
Alcoolismo/diagnóstico , Cirrose Hepática Alcoólica/cirurgia , Transplante de Fígado , Transferrina/análogos & derivados , Adulto , Idoso , Alcoolismo/classificação , Alcoolismo/psicologia , Biomarcadores/sangue , Etanol/sangue , Feminino , Seguimentos , Humanos , Transplante de Fígado/psicologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Inquéritos e Questionários , Transferrina/metabolismo
10.
Transplantation ; 58(5): 560-5, 1994 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8091482

RESUMO

Many transplant centers are reluctant to accept alcoholic patients for OLT because of their supposed potential for alcoholic recidivism and poor compliance with the required immunosuppressive regimen, both of which result in graft failure. Only inconclusive data related to these arguments are available. From May 1982 to January 1993, 58 patients received OLT at our institution for end-stage cirrhosis, where alcohol was the only toxic component. The indication for OLT in these patients was considered with particular attention to recidivism and compliance. Overall survival in this group was 71% and 63% at 1 and 5 years, respectively, with an average survival time of 78 months. Actuarial survival of patients transplanted since January 1989 (n = 37) was 86% and 83% at 1 and 2 years (average survival 42 months). Nonfatal clinical endpoints were analyzed in those patients surviving at least 3 months (n = 44). Return to alcohol abuse has been documented in 14 persons at routine short-term outpatient checkups. The estimated risk for alcoholic recidivism amounts to 31%, with a median follow-up of 33 months. Compliance with immunosuppressive regimen was expressed as a dependent value of acute rejection episodes (0.3 per patient, median follow-up 33 months), chronic rejection (occurred in none of the patients), and measurements of CsA HPLC blood trough level (92.2% within the target range). The preversus postoperative improvement of employment, marital, and social status after OLT showed a statistically significant difference. Unwillingness to offer OLT to individuals with alcoholic liver disease because of failure to demonstrate 100% long-term abstinence appears difficult to defend in the face of good results in survival, compliance, and social rehabilitation.


Assuntos
Alcoolismo/psicologia , Cirrose Hepática Alcoólica/cirurgia , Transplante de Fígado , Cooperação do Paciente , Adulto , Idoso , Ciclosporina/sangue , Ciclosporina/uso terapêutico , Emprego , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Humanos , Terapia de Imunossupressão , Transplante de Fígado/imunologia , Masculino , Estado Civil , Pessoa de Meia-Idade , Recidiva
11.
Transplantation ; 57(5): 665-9, 1994 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8140629

RESUMO

L-Arginine plays an important role in protecting animals against ammonia intoxication, enhances immune function, stimulates wound healing, and is the precursor for the endothelium-derived relaxing factor, recently recognized as nitric oxide (NO). In this study, we investigated the influence of hepatic reperfusion on amino acid metabolism after human OLT. After 10 sec of reperfusion, the arterial plasma levels of L-arginine dropped from 105 +/- 12 mumol/L to 3.8 +/- 0.6 mumol/L (P < 0.001), whereas plasma ornithine increased from 40 +/- 5.5 mumol/L to 129 +/- 15 mumol/L (P < 0.001). The reduced L-arginine levels remained subnormal for several hours after OLT. This drop in plasma L-arginine was due to an arginase release from the implanted graft. Immediately after reperfusion, the plasma concentrations of arginase increased from pretransplantation values of 18 +/- 13 IU/L to 2384 +/- 1456 IU/L (P < 0.01). Measurement of plasma nitrite (NO2-) and nitrate (NO3-), which are the stable end products of NO, revealed that NO2- decreased about 50% after reperfusion (from 1.64 +/- 0.32 mumol/L to 0.80 +/- 0.17 mumol/L; P < 0.001), whereas NO3- levels remained unchanged (76 +/- 23 mumol/L vs. 63 +/- 8 mumol/L). We conclude that hepatic reperfusion causes L-arginine deficiency by liberating high amounts of arginase from the implanted graft. This L-arginine depletion may influence the NO synthesis in patients after OLT.


Assuntos
Arginina/deficiência , Transplante de Fígado , Adulto , Arginase/sangue , Arginase/metabolismo , Arginina/sangue , Feminino , Veia Femoral/química , Humanos , Transplante de Fígado/fisiologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Artéria Radial/química
12.
Transplantation ; 69(11): 2454-5, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10868660

RESUMO

BACKGROUND: Oral ingestion of potassium dichromate produces a complex spectrum of complications. It has an extremely poor prognosis and usually leads to rapid death. METHODS: We report the case of a 16-year-old male patient who was admitted to hospital after oral ingestion of potassium dichromate with suicidal intention. RESULTS: The patient's condition deteriorated, and he became comatose within 5 days in spite of immediate attempts at detoxification. Because of irreversible liver failure, which occurred within 2 days after admission, and because of cerebral edema, the decision to perform a liver transplantation was made. On day 6 after admission, a compatible donor liver was transplanted. The course of liver transplantation and the patient's subsequent recovery were uneventful. CONCLUSION: The rationale for the delayed transplantation was to avoid damage of the new organ because of high serum chromium levels. Despite severe organ damage, the chromium content of the liver was increased. To the authors' knowledge, this is the first case report of acute toxic liver failure, caused by potassium dichromate poisoning, treated successfully by means of liver transplantation.


Assuntos
Falência Hepática/induzido quimicamente , Falência Hepática/cirurgia , Transplante de Fígado , Dicromato de Potássio/intoxicação , Doença Aguda , Adolescente , Edema Encefálico/induzido quimicamente , Humanos , Masculino , Tentativa de Suicídio
13.
Transplantation ; 71(6): 744-5, 2001 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-11330535

RESUMO

BACKGROUND: It is well known that the bactericidal effect of beta-lactam antibiotics is closely related to the time which the serum concentration of the antibiotic remains above the minimal inhibitory concentration of the target pathogen. Thus, the optimal administration of beta-lactam antibiotics would be the continuous infusion of the drug. METHODS: We present a case report with a critically ill double-lung transplanted patient with pneumonia due to a multidrug-resistant Pseudomonas aeruginosa who received continuously 8 g meropenem/24 hr. Based on a previous pharmacokinetic study showing that continuous infusion of meropenem is at least equivalent to intermittent administration this case report is reported to demonstrate the clinical efficacy of continuous infusion. RESULTS: C-reactive protein and pneumonia decreased rapidly when clinical conditions were improved significantly. Continuous administration of meropenem did not interfere with cyclosporine, no side effects were seen, and the patient's renal function was not impaired during the whole period of treatment. CONCLUSION: The continuous administration of beta-lactam antibiotics is a powerful application in critically ill patients to intensify antimicrobial therapy.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Pseudomonas/tratamento farmacológico , Resistência beta-Lactâmica/fisiologia , Resistência a Múltiplos Medicamentos , Humanos , Transplante de Pulmão/efeitos adversos , Masculino , Pessoa de Meia-Idade , beta-Lactamas
14.
Transplantation ; 71(11): 1666-70, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11435980

RESUMO

BACKGROUND: Renal allograft rejection is associated with the expression of adhesion molecules on vascular endothelial and tubular epithelial cells. METHODS: To assess whether the number of cell adhesion molecules expressed in donor kidneys can predict early rejection or delayed graft function, kidney biopsies from 20 living and 53 cadaveric kidney donors were obtained before engraftment into the recipients and the expression of the cell adhesion molecules intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and endothelial leukocyte adhesion molecule (E-selectin) were determined by immunohistochemistry. RESULTS: All biopsies from living donors showed significantly lower expression of ICAM-1 and VCAM-1 compared to biopsies from cadaveric donors. There was no difference in the expression of adhesion molecules on tubular cells between transplants with primary function compared to allografts with early rejection in living donated kidneys (ICAM-1: 2+/-8 vs. 3+/-8%; VCAM-1: 9+/-7 vs. 1+/-1%), as well as in cadaveric kidneys (ICAM-1: 38+/-29 vs. 39+/-38%; VCAM-1: 55+/-27 vs. 48+/-29%). The expression of ICAM-1 molecules on tubular cells was determined to be a predictor for the occurrence of delayed graft function in cadaveric kidneys (ICAM-1: 65+/-24* vs. 38+/-29% delayed graft versus primary graft function). No delayed graft function occurred in recipients of living donated kidneys. CONCLUSIONS: These data suggest that adhesion molecule expression in donor biopsies is not a predictor for early allograft rejection, but can be used as a marker for the development of postischemic acute renal allograft failure.


Assuntos
Selectina E/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Transplante de Rim/efeitos adversos , Rim/fisiopatologia , Doadores de Tecidos , Molécula 1 de Adesão de Célula Vascular/metabolismo , Adulto , Biópsia , Humanos , Imuno-Histoquímica , Rim/metabolismo , Rim/patologia , Pessoa de Meia-Idade , Período Pós-Operatório , Prognóstico , Insuficiência Renal/etiologia , Insuficiência Renal/fisiopatologia
15.
Transplantation ; 64(8): 1129-34, 1997 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-9355828

RESUMO

BACKGROUND: The aim of the present analysis was to define the role of simultaneous heart and kidney transplantation (HNTX) using organs from the same donor by evaluation of clinical strategy and achieved outcome compared with a reference group of concurrently single heart transplant (HTX) and kidney transplant (NTX) recipients. Compared with other organ combinations (pancreas-kidney, heart-lung), HNTX has been performed infrequently and is reported mainly as case records in the literature. Because of expansion of recipient selection criteria for HTX and NTX, the number of patients requiring simultaneous replacement of both organs is increasing. METHODS: Six HNTX recipients, three of them suffering from long-standing type I diabetes, received transplants between September 1990 and March 1996 and were analyzed in terms of clinical and immunological demographics and outcome. They were compared with 379 HTX and 769 NTX recipients operated upon within this period. RESULTS: Survival for HNTX is 100% with a mean follow-up of 32.7+/-21.1 months. Cold ischemic time of the kidney was significantly shorter for HNTX than for NTX (6.5+/-1.0 hr vs. 22.1+/-6.8 hr, P<0.005). Although HNTX patients received HLA-unmatched grafts, no rejection of the kidney has been observed to date. There was no difference for rejection of the heart in HNTX compared to HTX recipients. CONCLUSIONS: Satisfying results are obtained by HNTX and justify the use of two organs for one recipient. The favorable immunological behavior of the kidney despite use of HLA-unmatched grafts is most probably explained by higher immunosuppression and short cold ischemic time, although a combination effect cannot be excluded.


Assuntos
Insuficiência Cardíaca/cirurgia , Transplante de Coração , Falência Renal Crônica/cirurgia , Transplante de Rim , Adulto , Estudos de Coortes , Feminino , Sobrevivência de Enxerto/fisiologia , Antígenos HLA-A/análise , Antígenos HLA-B/análise , Antígenos HLA-DR/análise , Transplante de Coração/imunologia , Transplante de Coração/fisiologia , Humanos , Transplante de Rim/imunologia , Transplante de Rim/fisiologia , Masculino , Pessoa de Meia-Idade
16.
Transplantation ; 63(9): 1225-33, 1997 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-9158014

RESUMO

BACKGROUND: The release of liver arginase after orthotopic liver transplantation (OLT) causes a deficiency of L-arginine and nitrite in the plasma. This deficiency is possibly related to pulmonary hypertension and reduced hepatic blood flow, which are commonly observed in the immediate reperfusion period. The aim of this study was to evaluate the impact of L-arginine supplementation on metabolic and hemodynamic parameters during liver reperfusion after OLT in pigs. METHODS: Thirteen pig OLTs (control group, n=6; arginine group, n=7) were performed by a standard technique. Cold ischemic time was 20 hr. L-Arginine was infused at a dosage of 500 mg/kg body weight into the donor pigs (30 min before liver explantation) and also into the recipients (over a period of 3 hr from the beginning of the reperfusion period). At the end of the experimental study, the pigs were killed with an overdose of potassium. RESULTS: In the control group, liver revascularization increased plasma arginase concentrations (+615%) and reduced plasma levels of L-arginine (-87%), nitrite (-82%), and nitrate (-53%). Infusion of L-arginine increased plasma levels of L-arginine from 94+/-21 micromol/L to 1674+/-252 micromol/L (P<0.001), L-ornithine from 46+/-8 micromol/L to 2215+/-465 micromol/L (P<0.001), and L-citrulline from 58+/-8 micromol/L to 116+/-34 micromol/L (P<0.001), but had no effect on plasma levels of nitrite and nitrate. Administration of L-arginine in the donor pigs did not produce any systemic or organ-specific hemodynamic alterations. Infusion of L-arginine into the recipient pigs improved cardiac performance (increase in heart rate [+61%, P=0.017] and cardiac index [+53%, P=0.005], reduction in pulmonary capillary wedge pressure [-54%, P=0.014]). Moreover L-arginine infusion increased oxygen consumption (+65%, P=0.003), reduced pulmonary vascular resistance index (P=0.001), stimulated portal venous blood flow (P=0.014), and elevated body temperature during the reperfusion period (P=0.007). CONCLUSIONS: From these data, we conclude that the infusion of L-arginine during OLT improves the hemodynamic performance of the heart, lung, and liver.


Assuntos
Arginina/farmacologia , Débito Cardíaco/fisiologia , Hipertensão Pulmonar/tratamento farmacológico , Transplante de Fígado/efeitos adversos , Fígado/irrigação sanguínea , Resistência Vascular/efeitos dos fármacos , Animais , Arginina/sangue , Nitrogênio da Ureia Sanguínea , Feminino , Hemodinâmica/fisiologia , Humanos , Hipertensão Pulmonar/etiologia , Infusões Intravenosas , Circulação Hepática/efeitos dos fármacos , Circulação Hepática/fisiologia , Masculino , Nitratos/sangue , Nitritos/sangue , Oxigênio/sangue , Traumatismo por Reperfusão/tratamento farmacológico , Suínos
17.
Transplantation ; 69(10): 2079-84, 2000 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-10852600

RESUMO

BACKGROUND: A 35-year period of clinical development resulted in orthotopic liver transplantation (OLT) becoming a standardized surgical procedure. Despite this progress, the rate of technical complications is still high. Although the main problem in most analyses is vascular or bile duct failure, we observed a remarkable number of parenchymal liver injuries that led to intraoperative problems. Our aim, therefore, is to present an overall report on the incidence, treatment, and clinical course of parenchymal liver injuries in OLT. METHODS: Five hundred seventy-two consecutive OLT procedures performed between 1988 and 1998 were analyzed in a retrospective study. Parenchymal liver injury was diagnosed by means of examination of the surgical reports. Donor- and recipient-related data followed the medical report. The lesions were classified according to the Organ Injury Scale. RESULTS: Parenchymal liver injury was diagnosed in 23 patients (4%). The lesions were classified as grade Ia (13.1%), grade Ib (13.1%), grade IIb (52.1%), grade IIIa (17.1%), and grade IIIb (4.3%). In 19 patients (82.6%), the lesion was detected during OLT, and in four patients (17.4%), during relaparotomy. The latter group showed significantly higher-grade injuries. Treatment was suture or fibringlue alone, 17.4%; fibringlue and hemostyptics, 26.1%, mesh wrapping 30.4%, and mesh packing 26.1%. Seven patients (30.4%) underwent relaparotomy. Further active bleeding was not found in any of them. Statistical analysis found a correlation between injury grade and relaparotomy rate. No patients died as a result of parenchymal liver injury. CONCLUSIONS: Parenchymal liver injuries can be treated well, with no adverse effect on patient or graft survival. An early decision concerning the surgical procedure for controlling hemorrhage is required. A basically aggressive therapeutic approach might avoid further complications relating to reperfusion edema.


Assuntos
Transplante de Fígado/métodos , Transplante de Fígado/fisiologia , Fígado/patologia , Adulto , Cadáver , Causas de Morte , Feminino , Hemorragia , Humanos , Fígado/lesões , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/terapia , Reoperação , Estudos Retrospectivos , Doadores de Tecidos/estatística & dados numéricos
18.
Transplantation ; 58(2): 179-83, 1994 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-8042235

RESUMO

Several studies have shown that the postoperative course of cytokines such as TNF-alpha or IL-6 is predictive of rejection and infection after human orthotopic liver transplantation (OLT). The aim of this prospective clinical trial was to evaluate the impact of transhepatic metabolism of endotoxin (ET), tumor necrosis-factor-alpha (TNF-alpha), and interleukin-6 (IL-6) after hepatic ischemia/reperfusion on the postoperative graft function. In 13 consecutive elective adult OLT patients with primary grafts, we determined concentrations of ET, TNF-alpha, and IL-6 in the radial artery, portal vein, and right hepatic vein at 1, 4, 7, 10, and 13 min after reperfusion. Of the 13 patients, four had ET levels below the detection limit (< 10 ng/L), and one patient had extremely high ET concentrations (151 ng/L in the hepatic vein). In the remaining patients the mean ET levels were 26 +/- 14, 26 +/- 15, and 24 +/- 14 ng/L in the portal vein, hepatic vein, and in the radial artery, respectively. These values indicate that in patients with a moderately elevated ET level, no transhepatic concentration differences of ET exist. However, in the patient with severe endotoxemia, the liver was apparently an ET-producing organ (HV-P: 29 +/- 13 ng/L). TNF-alpha levels were not measurable in four patients, and varied between 15 and 72 pg/ml (portal vein) in the remaining patients. The transhepatic concentration differences (HV-P and HV-A, respectively) of patients with PNF or dysfunction were higher than in those with "good" or "excellent" graft function (HV-P: 160 +/- 122 pg/ml vs. 7.3 +/- 9.7 pg/ml; P < 0.01 and HV-A: 137 +/- 101 pg/ml vs. 3.9 +/- 12 pg/ml; P < 0.01, respectively). Arterial IL-6 levels were below 88 pg/ml (mean value: 31 +/- 20 pg/ml) at the beginning of the operation, and increased considerably in three patients during the anhepatic phase and after reperfusion. No clinical correlation was found with the transhepatic concentration differences of IL-6. We conclude that in OLT patients without infection no transhepatic ET exchange was documented. However, a stimulated hepatic TNF-alpha release seems to be predictive of the beginning of liver dysfunction.


Assuntos
Endotoxinas/sangue , Interleucina-6/sangue , Circulação Hepática/fisiologia , Transplante de Fígado/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Idoso , Feminino , Sobrevivência de Enxerto , Veias Hepáticas , Humanos , Masculino , Pessoa de Meia-Idade , Veia Porta , Estudos Prospectivos , Artéria Radial , Reperfusão
19.
Transplantation ; 61(4): 554-60, 1996 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-8610380

RESUMO

Despite major advances in immunopharmacology, virtually all patients receive the same center-specific immunosuppressive regimen following orthotopic liver transplantation (OLT). The present analysis was performed on the hypothesis that the original disease representing the indication for OLT leads to a different initial immunological situation of the patient. The type of original disease might therefore be a predisposing factor for acute rejection episodes and influence graft and patient survival. From January 1988 to July 1994, 34 patients received OLT at our institution for end-stage primary biliary cirrhosis (group 1) and 66 patients for end-stage alcoholic cirrhosis (group 2). Overall survivals at 1 and 5 years in group 1 versus group 2 were 67% versus 80% and 50% versus 68%, respectively (P<0.04). Retransplantation was performed in 21% of patients from group 1 and in 6% from group 2. The estimated risk for freedom from acute rejection amounts to 38% in group 1 compared with 59% in group 2 (P<0.02). Multivariate regression analysis of potential risk factors identified only the underlying disease as independent predictor. Analysis of cumulative rates of clinically relevant rejection episodes stratified by group revealed 0.29 and 0.05 episodes per patient at one month and 0.80 and 0.06 at six months (P<0.009) respectively. In our clinical experience it was possible to confirm the hypothesis that the underlying disease is the reason for a significantly different incidence of acute rejection episodes and that it subsequently influences graft and patient survival. This approach to an individually adapted immunosuppressive therapy should be taken into consideration and other appropriate parameters investigated.


Assuntos
Rejeição de Enxerto/imunologia , Cirrose Hepática Alcoólica/imunologia , Cirrose Hepática Biliar/imunologia , Transplante de Fígado/imunologia , Doença Aguda , Adulto , Idoso , Infecções Bacterianas/etiologia , Doença Crônica , Feminino , Seguimentos , Sobrevivência de Enxerto/imunologia , Humanos , Cirrose Hepática Alcoólica/cirurgia , Cirrose Hepática Biliar/cirurgia , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Viroses/etiologia
20.
Surgery ; 97(4): 436-42, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3983819

RESUMO

The metabolic derangement of sepsis leads to changes of the plasma and muscle amino acid (AA) pattern. In this study the influence of a septic process on liver AA pattern was investigated. In seven patients with abdominal sepsis, liver AA concentrations were determined during surgery and compared with those of four patients who had undergone cholecystectomy. In sepsis lowered AA levels were found for most of the AAs. Outstanding decreases exhibited the levels of the gluconeogenetic AAs (especially threonine and alanine), the branched chain AAs, lysine, and taurine. In the patients who did not survive the septic process, the depletion of these AAs was even amplified. Slightly increased AA levels were analyzed for P-ethanolamine, cystathionine, citrulline, beta-alanine, tyrosine, and phenylalanine. The results indicate a disturbed free AA pattern of the septic liver. Despite the increased flux of gluconeogenetic AA from muscle to liver in sepsis, as reported by several authors, no accumulation of these AAs occurs in the liver.


Assuntos
Aminoácidos/metabolismo , Infecções Bacterianas/metabolismo , Fígado/metabolismo , Adolescente , Adulto , Idoso , Aminoácidos/sangue , Infecções Bacterianas/sangue , Infecções Bacterianas/mortalidade , Biópsia por Agulha , Água Corporal/análise , Feminino , Humanos , Lipídeos/análise , Abscesso Hepático/metabolismo , Masculino , Pessoa de Meia-Idade , Pancreatite/metabolismo , Peritonite/metabolismo
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