RESUMO
BACKGROUND: Hepatitis B (HBV) and hepatitis C (HCV) virus infections are major risk factors affecting long-term morbidity and mortality after renal transplantation. Hepatitis prevalence is subject to geographical variations. OBJECTIVE: To compare and analyze the geographical prevalence, risk factors and impact of HBV and HCV infection in multinational cohorts of renal transplant recipients. METHODS: From 1989 - 2002, data on 12,856 kidney transplant recipients in 37 countries were collected within the prospective MOST (Multinational Observational Study in Transplantation). Subgroup analyses of hepatitis-related prevalence, risk factors and impact were conducted on patients whose HBV and HCV status was available at time of transplantation. Countries were substratified according to population prevalence of > or = 5% HBV or > or = 10% HCV. RESULTS: The prevalence of HBV was 2.9%, of HCV 8.7% and of HBV together with HCV 0.4%. Risk factors for hepatitis infection in renal transplant recipients were long dialysis time, retransplantation and blood transfusions. At each study endpoint up to 5 years after transplantation, no significant differences in graft function were observed, although the 1-year acute rejection rate tended to be lower in HCV+ patients. At 5 years post-transplant, there were no differences between the subgroups and regions regarding infections, post-transplant diabetes mellitus or malignancies including PTLD. CONCLUSIONS: Overall, HCV infections are more prevalent than HBV. Despite large geographical differences in prevalence, HBV and HCV status did not appear to have a significant impact on renal graft function, infections, malignancies and post-transplant diabetes mellitus up to 5 years after renal transplantation throughout the MOST countries.
Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Transplante de Rim , Adulto , Feminino , Hepatite B/transmissão , Hepatite C/transmissão , Humanos , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco , Resultado do TratamentoRESUMO
BACKGROUND: Chronic liver disease resulting from hepatitis B (HBV) and hepatitis C (HCV) virus infections is still a major concern in kidney recipients. Our aim was to evaluate the prevalences, risk factors, and impact of HBV and HCV infections in adult renal transplant recipients in Germany. MATERIALS AND METHODS: Data were collected on 1633 kidney recipients transplanted between 1989 and 2002 at the 21 German renal transplant centers participating in MOST, the prospective Multinational Observational Study in Transplantation. Subgroup analyses compared HBV- and HCV-positive patients vs those with HBV/HCV-negative serology at the time of transplantation. RESULTS: The prevalences of 4.4% (n = 72) for HBV and 5.8% (n = 94) for HCV showed a marked decline over the last 15 years. Retransplantations were significantly more common among HBV+ (29%) and HCV+ (36%) than HBV-/HCV- patients (12%). HCV+ patients experienced significantly longer dialysis times and received significantly more pretransplantation blood transfusions. Between all groups, no significant differences were observed in acute rejection rate at 12 months or in renal graft function up to 5 years posttransplantation (mean glomerular filtration rate: HBV+, 57.3 mL/min; HCV+, 58.5 mL/min; HBV-/HCV-, 59 mL/min). No progressive elevations in liver enzymes and bilirubin were noted during the 5-year observation period. CONCLUSIONS: HBV and HCV infections currently have a low prevalence among German kidney graft recipients. Long dialysis times, blood transfusions, and retransplantations were identified as risk factors for hepatitis infections. At 5 years posttransplantation, kidney and liver functions did not differ significantly between HBV+ and HCV+ vs HBV-/HCV- renal transplant recipients.
Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Transplante de Rim/fisiologia , Adulto , Transfusão de Sangue , Feminino , Alemanha , Hepatite B/transmissão , Hepatite C/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Resultado do TratamentoRESUMO
INTRODUCTION: We collected data from kidney recipients with a functioning graft at German kidney transplant centers in order to analyze the efficacy of various cyclosporine (CsA)-based immunosuppressive strategies, the effects of different perioperative and maintenance regimens, and the impact of donor source on clinical outcome. METHODS: As part of the ongoing prospective Multinational Observational Study in Transplantation (MOST), data for both prospective and retrospective analysis were collected from kidney recipients over 18 years bearing a functioning graft that was transplanted at 21 German kidney transplant centers between 1987 and 2002. RESULTS: Data from 1223 renal graft recipients, including their CsA-based immunosuppressive regimens, were stratified as: 402 de novo patients (median 6.8 months posttransplant) and 821 patients on maintenance therapy (median 71 months posttransplant). Triple regimens with CsA + mycophenolate mofetil (MMF) + steroids (Ste) currently comprise the major perioperative immunosuppressive strategies in Germany (de novo 65%). IL-2 receptor antagonist (IL-2Ra) use is increasing (de novo 18%, maintenance 4%), while mono and dual regimen use de novo is declining (de novo 4%, maintenance 20%). Among 689 patients transplanted between 1987 and 2002 with outcome data, the mean incidence of acute rejection during the first posttransplant year was 21.6%. Rejection rates on initial therapy with CsA + MMF + Ste +/- antibodies (n = 517) averaged 17.8%. CONCLUSIONS: Between 1987 and 2002, CsA-based immunosuppression combined with MMF and Ste became the most commonly used strategy for both initial and maintenance therapy after kidney transplantation in Germany, yielding the low acute rejection rates particularly when combined with IL-2Ra.
Assuntos
Ciclosporina/uso terapêutico , Transplante de Rim/imunologia , Adulto , Soro Antilinfocitário/uso terapêutico , Quimioterapia Combinada , Alemanha , Rejeição de Enxerto/epidemiologia , Humanos , Terapia de Imunossupressão/métodos , Terapia de Imunossupressão/tendências , Imunossupressores/uso terapêutico , Doadores Vivos , Muromonab-CD3/uso terapêutico , Seleção de Pacientes , Complicações Pós-Operatórias/epidemiologia , Transplante Homólogo , Resultado do TratamentoRESUMO
This ongoing multicenter prospective observational study was undertaken in de novo renal allograft recipients managed with cyclosporine (CsA) trough (C0) and 2-hour postdose (C2) level monitoring at defined times so as to assess the risk for an acute rejection episode or allograft dysfunction. The renal transplant recipients (n = 159) were enrolled at 11 German centers. The 6-month posttransplant data from 138 patients were evaluable for this interim analysis. Mean C2 levels (ng/mL), which were measured by liquid chromatography-tandem mass spectrometry at a central laboratory, were: days 3 to 5: 873.1 +/- 391.9; days 7 to 10: 939.1 +/- 422.8; days 14 to 28: 1116.3 +/- 497.6; 3 months: 905.0 +/- 316.8; and after 6 months: 787.0 +/- 276.5. To identify patients at higher risk for acute rejection or allograft dysfunction, we calculated the relative CsA absorption capacity (C2 [ng/mL]/morning dose [mg/kg]; CsA-Abs), yielding mean values on days 3 to 5: 284.4 +/- 115.1; days 7 to 10: 306.7 +/- 134.8; days 14 to 28: 382.5 +/- 164.7; month 3: 501.5 +/- 168.8; month 6: 512.7 +/- 176.5. Three groups were distinguished by CsA-Abs at days 7 to 10: low absorbers (CsA-Abs < 200), normal absorbers (CsA-Abs 200 to 350), and high absorbers (CsA-Abs > 350). A between-group comparison of absorption level at 6 months posttransplant revealed the incidences of biopsy-proven acute rejection and Cockcroft-Gault formula-based mean glomerular filtration rates of 23.8% and 54.7 +/- 19.0 mL/min, 22.6% and 59.5 +/- 20.7 mL/min, and 17.6% and 67.7 +/- 23.5, respectively. In conclusion, mean C2 levels >1000 ng/mL are attained within 2 to 4 weeks, with CsA-Abs increasing continuously over the first 6 posttransplant months. High CsA absorbers show a propensity toward good allograft function and lower acute rejection rates at 6 months after renal transplantation.
Assuntos
Ciclosporina/uso terapêutico , Transplante de Rim/imunologia , Área Sob a Curva , Ciclosporina/sangue , Ciclosporina/farmacocinética , Monitoramento de Medicamentos/métodos , Alemanha , Taxa de Filtração Glomerular/efeitos dos fármacos , Rejeição de Enxerto/epidemiologia , Humanos , Taxa de Depuração Metabólica , Estudos ProspectivosRESUMO
Many neuropathological and experimental studies suggest that the degeneration of dopaminergic terminals and axons precedes the demise of dopaminergic neurons in the substantia nigra, which finally results in the clinical symptoms of Parkinson disease (PD). The mechanisms underlying this early axonal degeneration are, however, still poorly understood. Here, we examined the effects of overexpression of human wildtype alpha-synuclein (αSyn-WT), a protein associated with PD, and its mutant variants αSyn-A30P and -A53T on neurite morphology and functional parameters in rat primary midbrain neurons (PMN). Moreover, axonal degeneration after overexpression of αSyn-WT and -A30P was analyzed by live imaging in the rat optic nerve in vivo. We found that overexpression of αSyn-WT and of its mutants A30P and A53T impaired neurite outgrowth of PMN and affected neurite branching assessed by Sholl analysis in a variant-dependent manner. Surprisingly, the number of primary neurites per neuron was increased in neurons transfected with αSyn. Axonal vesicle transport was examined by live imaging of PMN co-transfected with EGFP-labeled synaptophysin. Overexpression of all αSyn variants significantly decreased the number of motile vesicles and decelerated vesicle transport compared with control. Macroautophagic flux in PMN was enhanced by αSyn-WT and -A53T but not by αSyn-A30P. Correspondingly, colocalization of αSyn and the autophagy marker LC3 was reduced for αSyn-A30P compared with the other αSyn variants. The number of mitochondria colocalizing with LC3 as a marker for mitophagy did not differ among the groups. In the rat optic nerve, both αSyn-WT and -A30P accelerated kinetics of acute axonal degeneration following crush lesion as analyzed by in vivo live imaging. We conclude that αSyn overexpression impairs neurite outgrowth and augments axonal degeneration, whereas axonal vesicle transport and autophagy are severely altered.
Assuntos
Neurônios Dopaminérgicos/metabolismo , Degeneração Neural/genética , Doença de Parkinson/genética , alfa-Sinucleína/biossíntese , Substituição de Aminoácidos , Animais , Autofagia/genética , Axônios/patologia , Dopamina/metabolismo , Neurônios Dopaminérgicos/patologia , Regulação da Expressão Gênica , Humanos , Neuritos/patologia , Doença de Parkinson/patologia , Ratos , Substância Negra/metabolismo , Substância Negra/patologia , alfa-Sinucleína/genéticaRESUMO
The regulation of steady state levels of follistatin (FS) messenger RNA (mRNA) was examined in a rat renal mesangial cell line in tissue culture. A specific 32P-radiolabeled antisense probe was used which corresponds to the 3' end of exon 5 together with the 5' end of exon 6 of the rat FS gene, and which distinguishes between the two different forms of FS mRNA. In addition, a specific 35S-radiolabeled probe for the ubiquitous protein cyclophilin was developed and used as an internal standard. Total RNA was harvested from confluent cell cultures to yield four independent samples per treatment/time point, and equal amounts of RNA from every sample in a given experiment were subjected to S1-nuclease analysis for the estimation of specific mRNA levels. Treatment of the cultured cells with epidermal growth factor (10 nM) caused an 8- to 9-fold increase in the FS mRNA level after 4 h, but no consistent change was observed after treatment with basic fibroblast growth factor (0.28 or 0.56 nM), somatostatin (3.7-73 nM), angiotensin II (0.1-2500 nM), or FS itself (0.29 nM) for between 4 and 48 h. Neither activin (0.5 or 1.2 nM) nor inhibin (0.64 nM) changed the FS mRNA level in the mesangial cell line during a 24-h treatment. FS mRNA levels in the cells also were not affected by a 48-h treatment with the steroids dihydrotestosterone (1-1000 nM), estradiol (1 and 100 nM), and the antiprogesterone RU 486 (1000 nM), whereas 100 nM RU 28362 (a synthetic glucocorticoid) caused a 5- to 6-fold increase and 1000 nM progesterone increased the FS mRNA level up to 3.5-fold above control. Retinoic acid, a vitamin A derivative, significantly increased the FS steady state mRNA level at 3 nM, and at 1000 nM stimulated FS mRNA up to 5-fold within 4 h, whereas incubation of the cells with 30 microM prostaglandin E2 for 4 h caused a 10-fold increase. The FS mRNA level increased 3- and 4-fold within 4 h during incubation of the cells with 100 nM phorbol 12-myristate, 13-acetate, and 25 microM forskolin, respectively, whereas the calcium ionophore A23187 (1-100 microM) caused no change within this timespan. None of the tested hormones had an obvious effect on the ratio of the two different forms of FS mRNA (FS 344:FS 317).(ABSTRACT TRUNCATED AT 400 WORDS)
Assuntos
Mesângio Glomerular/fisiologia , Glicoproteínas/genética , RNA Mensageiro/metabolismo , Ativinas , Isomerases de Aminoácido/genética , Androstanóis/farmacologia , Angiotensina II/farmacologia , Animais , Sequência de Bases , Proteínas de Transporte/genética , Linhagem Celular , Células Cultivadas , Ciclosporinas/metabolismo , Di-Hidrotestosterona/farmacologia , Dinoprostona/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Estradiol/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Folistatina , Expressão Gênica/efeitos dos fármacos , Inibinas/farmacologia , Mifepristona/farmacologia , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Peptidilprolil Isomerase , Progesterona/farmacologia , RNA/genética , RNA/isolamento & purificação , Sondas RNA , RNA Mensageiro/genética , Ratos , Somatostatina/farmacologia , Tretinoína/farmacologiaRESUMO
Follistatin (FS) is the specific binding protein of activin; it has a broad tissue distribution and is also found in serum. The ovary has the highest level of FS expression, but ovariectomy does not cause a permanent reduction in the serum FS level. Therefore, the source of FS in serum is still elusive. As a regulatable, nongonadal source of serum FS could influence ovarian and pituitary-derived hormone secretion and thus reproductive function, we searched for a source of extragonadal FS expression that might contribute to the FS protein level in serum. We found that endothelial cells from blood vessels express FS messenger RNA (mRNA) and protein; therefore, we studied the regulation of steady state levels of FS mRNA in porcine endothelial cells from aorta (AEC) and brain microvessels (BMVEC) in tissue culture. For detection of FS mRNA, a specific 32P-radiolabeled antisense probe and a S1-nuclease protection assay were used. FS steady state levels of AEC decreased with time in culture, i.e. postconfluent AEC had lower FS mRNA levels than confluent cultures, which, in turn, had lower FS mRNA levels than subconfluent cell cultures. FS mRNA levels in AEC were induced by increasing concentrations of FCS and stimulated by 30 micrograms/ml endothelial cell growth supplement. FS mRNA levels in AEC and BMVEC increased approximately 20-fold within 4 h during incubation of the cells with 100 nM phorbol 12-myristate, 13-acetate, whereas 0.5 nmol/ml forskolin tested in AEC for between 4-48 h had no significant effect. Furthermore, 0.1 microM ocadaic acid, an inhibitor of serine/threonine phosphatases 1 and 2A, caused a significant increase in FS mRNA levels. FS mRNA levels in AEC were not significantly affected by various concentrations of porcine FSH, epidermal growth factor, or retinoic acid for between 4-48 h. Treatment of the cells with 0.01-10 micrograms/ml bacterial lipopolysaccharides (LPS) caused a dose-dependent increase (up to 10-fold) in FS mRNA steady state level in AEC, whereas 1-1000 nM RU 28362, a synthetic glucocorticoid, inhibited FS mRNA steady state levels in a dose-dependent manner. The induction of FS mRNA with 1 microgram/ml LPS was completely blocked by 100 nM RU 28362, and the stimulatory effects of LPS were only visible after 4 h of treatment, not after 24 or 48 h. The same effects were observed with BMVEC. We, furthermore, analyzed FS protein secretion of AEC by Western blotting and demonstrated that FS proteins were secreted into the culture medium upon stimulation with LPS. None of these treatments had an obvious effect on the ratio of the two different forms of FS mRNA (FS 344:FS 317). Besides the expression of FS mRNA in AEC and BMVEC, FS mRNA is also expressed in uncultured plexus choroideus epithel and meninges, and FS protein is found in human cerebrospinal fluid. From this study it is concluded that 1) endothelial cells from different tissues produce FS mRNA; 2) the FS mRNA levels of AEC and BMVEC are subjected to regulation by FCS, endothelial cell growth supplement, bacterial LPS, and the glucocorticoid RU 28362; 3) phosphatases and the protein kinase C-dependent, but not the protein kinase A-dependent, pathway are involved in regulating the steady state levels of FS mRNA in AEC and BMVEC; and 4) endothelial cells produce and secrete FS protein and are thus a likely source of FS in serum.
Assuntos
Androstanóis/farmacologia , Endotélio Vascular/metabolismo , Glucocorticoides/farmacologia , Glicoproteínas/biossíntese , Lipopolissacarídeos/farmacologia , Transcrição Gênica/efeitos dos fármacos , Animais , Aorta , Encéfalo , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Plexo Corióideo/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Feminino , Folistatina , Humanos , Inibinas/biossíntese , Cinética , Meninges/metabolismo , Microcirculação , Especificidade de Órgãos , Ovariectomia , Ovário/metabolismo , RNA Mensageiro/biossíntese , Salmonella , Suínos , Acetato de Tetradecanoilforbol/farmacologiaRESUMO
Apoptosis and necrosis in brain account for neurological sequelae in survivors of bacterial meningitis. In meningitis, several mechanisms may trigger death pathways leading to activation of transcription factors regulating caspases mRNA synthesis. Therefore, we used a multiprobe RNA protection assay (RPA) to examine the expression of 9 caspase-mRNA in the course of experimental Streptococcus pneumoniae meningitis in mouse brain. Caspase-6, -7 and -11 mRNA were elevated 6 hours after infection. 12 hours after infection caspases-1, -2, -8 and -12 mRNA rose. Caspase-14 mRNA was elevated 18 h and caspase-3 mRNA 24 h after infection. In situ hybridization detected caspases-3, -8, -11 and -12 mRNA in neurons of the hippocampal formation and neocortex. Development of sepsis was paralleled by increased transcription of caspases mRNA in the spleen. In TNFalpha-deficient mice all caspases examined were less upregulated, in TNF-receptor 1/2 knockout mice caspases-1, -2, -7, -11 and -14 mRNA were increased compared to infected control animals. In caspase-1 deficient mice, caspases-11, and -12 mRNA levels did not rise in meningitis indicating the necessity of caspase-1 activating these caspases. Hippocampal formations of newborn mice incubated with heat-inactivated S. pneumoniae R6 showed upregulation of caspase-1, -3, -11 and -12 mRNA. These observations suggest a tightly regulated caspases network at the transcriptional level in addition to the known cascade at the protein level.
Assuntos
Encéfalo/enzimologia , Caspases/biossíntese , Regulação Enzimológica da Expressão Gênica , Proteínas do Tecido Nervoso/biossíntese , Pneumonia Pneumocócica/enzimologia , Transcrição Gênica , Animais , Anexina A5/análise , Apoptose , Caspases/genética , Células Cultivadas , Indução Enzimática , Hipocampo/citologia , Hipocampo/enzimologia , Hibridização In Situ , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Necrose , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/genética , Pneumonia Pneumocócica/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores do Fator de Necrose Tumoral/deficiência , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/fisiologia , Fator de Necrose Tumoral alfa/deficiência , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/fisiologiaRESUMO
Lipoteichoic and teichoic acids are components of the cell wall of Streptococcus pneumoniae. A recently developed enzyme immunoassay was used in patients with pneumococcal meningitis to investigate lipoteichoic and teichoic acid concentrations in CSF at the first lumbar puncture in relation to the clinical outcome determined by the Glasgow Outcome Scale. Lipoteichoic and teichoic acid concentrations in CSF were significantly associated with neurologic sequelae and mortality in S. pneumoniae meningitis.
Assuntos
Lipopolissacarídeos/líquido cefalorraquidiano , Meningite Pneumocócica/líquido cefalorraquidiano , Meningite Pneumocócica/fisiopatologia , Ácidos Teicoicos/líquido cefalorraquidiano , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pré-Escolar , Avaliação da Deficiência , Feminino , Escala de Coma de Glasgow , Humanos , Técnicas Imunoenzimáticas/métodos , Lactente , Recém-Nascido , Masculino , Meningite Pneumocócica/complicações , Meningite Pneumocócica/mortalidade , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Concentração Osmolar , Punção EspinalRESUMO
The regulation of steady-state follistatin mRNA levels by different pituitary hormones and peptide factors was examined in granulosa cell cultures derived from diethylstilboestrol-treated immature rats. Cytosolic RNA from cell cultures was prepared by lysis and equal amounts of RNA from all samples were analysed with a solution-hybridization assay using a 32P-labelled antisense probe corresponding to a part of exon 5 together with a part of the 5' end of exon 6 of the rat follistatin gene. In addition, a specific 35S-labelled probe for cyclophilin was used as an internal standard. The results show that 5 micrograms FSH/l for 24 to 72 h stimulated steady-state follistatin mRNA levels, reaching levels 18.5-fold higher than controls. LH (0.2-100 micrograms/l) had only minor effects on follistatin mRNA levels in FSH-primed granulosa cells and prolactin, GH and IGF-I did not show any significant effects. Activin raised basal as well as FSH-stimulated steady-state follistatin mRNA levels up to ten- and twofold above controls respectively, whereas epidermal growth factor was found to inhibit FSH-stimulated follistatin mRNA levels in a dose-dependent manner. It is concluded that follistatin mRNA levels in granulosa cells are regulated by FSH rather than LH, and that the stimulation by FSH can be inhibited by epidermal growth factor but enhanced by activin. Activin alone was also capable of stimulating follistatin mRNA.
Assuntos
Glicoproteínas/genética , Células da Granulosa/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ativinas , Animais , Fator de Crescimento Epidérmico/farmacologia , Feminino , Hormônio Foliculoestimulante/farmacologia , Folistatina , Células da Granulosa/efeitos dos fármacos , Técnicas In Vitro , Inibinas/farmacologia , Hormônio Luteinizante/farmacologia , Sondas RNA , Ratos , Ratos Sprague-Dawley , Transdução de SinaisRESUMO
The role of TNF-alpha in the course of Wallerian degeneration of the sciatic nerve was studied in control and TNF-alpha deficient mice. In control animals, the characteristic phenomena of Wallerian degeneration such as axon and myelin degeneration as well as macrophage recruitment with subsequent myelin removal were observed. In TNF-alpha deficient mice, in contrast, macrophage recruitment into the degenerating nerves was impaired resulting in a delayed myelin removal. However, the myelin phagocytic capacity of macrophages was not affected as it could be demonstrated by a similar myelin load of control and TNF-alpha deficient macrophages. These data indicate that the main function of TNF-alpha during Wallerian degeneration is the induction of macrophage recruitment from the periphery without affecting myelin damage or phagocytosis.
Assuntos
Macrófagos/imunologia , Fagocitose , Nervo Isquiático/patologia , Fator de Necrose Tumoral alfa/fisiologia , Degeneração Walleriana/imunologia , Degeneração Walleriana/patologia , Animais , Contagem de Leucócitos , Ativação de Macrófagos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica , Bainha de Mielina/metabolismo , Nervo Isquiático/imunologia , Nervo Isquiático/metabolismo , Nervo Isquiático/cirurgia , Fator de Necrose Tumoral alfa/deficiência , Fator de Necrose Tumoral alfa/genética , Degeneração Walleriana/metabolismoRESUMO
Serum levels of circulating ICAM-1 are increased in various disorders including inflammatory diseases of the central nervous system (CNS). We recently described an association between high sICAM-1 levels in the serum of patients with multiple sclerosis and disease activity. The functional consequences of increased circulating adhesion molecules are not fully understood. This may simply arise as a consequence of inflammation or may have immune modulating properties. ICAM-1 plays an important role in the recruitment of activated lymphocytes to sites of inflammation within the CNS. We therefore tested the ability of soluble forms of ICAM-1 to prevent adhesion of activated lymphocytes to cerebral endothelial cells. Mitogen-activated blood mononuclear cells (PBMC) as well as PBMCs from patients with active multiple sclerosis adhered to cerebral endothelial cell cultures in vitro. This adhesion could be blocked if lymphocytes were preincubated with a recombinant form of soluble ICAM-1. In addition, serum from patients with active multiple sclerosis and high sICAM-1 levels blocked adhesion in a dose-dependent manner which was abrogated by pre-adsorption to an anti ICAM-1 antibody. Since soluble forms of ICAM-1 are able to block lymphocyte adhesion to cerebral endothelial cells, they may provide new therapeutic tools to interfere with the pathogenesis of inflammatory diseases of the CNS.
Assuntos
Circulação Cerebrovascular , Endotélio Vascular/fisiologia , Molécula 1 de Adesão Intercelular/farmacologia , Linfócitos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Endotélio Vascular/citologia , Humanos , Molécula 1 de Adesão Intercelular/sangue , Linfócitos/fisiologia , Monócitos/efeitos dos fármacos , Monócitos/fisiologia , Esclerose Múltipla/sangue , Esclerose Múltipla/fisiopatologia , Proteínas Recombinantes , SolubilidadeRESUMO
In implantable cardioverter-defibrillator therapy with endocardial lead systems, certain clinical variables are associated with defibrillation energy requirements. Because of the weak correlation coefficients, these variables cannot predict defibrillation thresholds in individual patients.
Assuntos
Cardioversão Elétrica , Fatores Etários , Amiodarona/uso terapêutico , Antiarrítmicos/uso terapêutico , Procedimentos Cirúrgicos Cardíacos , Doença das Coronárias/fisiopatologia , Desfibriladores Implantáveis , Cardioversão Elétrica/métodos , Eletrofisiologia , Desenho de Equipamento , Feminino , Previsões , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Isquemia Miocárdica/fisiopatologia , Análise de Regressão , Fatores Sexuais , Sotalol/uso terapêutico , Volume Sistólico , Taquicardia Ventricular/fisiopatologia , Fibrilação Ventricular/fisiopatologia , Fibrilação Ventricular/terapia , Função Ventricular EsquerdaRESUMO
The recent success of biventricular pacing with transvenously implantable left ventricular leads suggests that left ventricular leads may be useful for other modes of therapy. Animal studies showed small leads inserted into a left ventricular vein dramatically reduced defibrillation strength requirements. This article describes a human investigation of the feasibility of biventricular defibrillation. Fifty-one patients undergoing implantable cardioverter defibrillator (ICD) implantation were enrolled. After insertion of a standard ICD lead, a prototype over-the-wire left ventricular defibrillation lead was inserted through the coronary sinus and into a vein on the left ventricle. Lead insertion was guided by retrograde venography. The left ventricular lead's location was randomized to the anterior or posterior vein. Randomized, paired defibrillation threshold (DFT) testing was performed to compare a standard ICD shock configuration (Control: right ventricle- --> superior vena cava+ + CAN+) to 1 of 3 biventricular shock configurations. In the anterior vein, the left ventricular lead was tested with either a single biphasic shock from right ventricle + left ventricle- --> superior vena cava+ + CAN+ or a dual biphasic shock. In the posterior vein, the left ventricular lead was tested with a dual biphasic shock. Dual shocks consisted of a 40% tilt biphasic shock from right ventricle- --> superior vena cava+ + CAN+ followed by another 40% tilt biphasic shock from left ventricle- --> superior vena cava+ + CAN+, delivered from a single 225 microF capacitance. Left ventricular lead positioning was successful in 41 of 46 patients (89%). Mean left ventricular lead insertion time was 17 +/- 17 minutes and 13 +/- 15 minutes for anterior and posterior locations, respectively. Mean DFTs were not statistically lower for the left ventricular shock configurations, but retrospective analysis showed a well-defined region of the posterolateral left ventricle where consistent DFT reduction was achieved with dual shocks (14.0 +/- 2.7 J vs 7.8 +/- 0.9 J; n = 5; p = 0.04). There were no adverse events requiring intervention due to the use of the left ventricular lead. Biventricular defibrillation is feasible and safe under the conditions used in this study. Additional studies are needed to verify whether dual shocks with posterolateral left ventricular lead positions consistently reduce DFTs.
Assuntos
Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Taquicardia Ventricular/terapia , Fibrilação Ventricular/terapia , Idoso , Vasos Coronários , Cardioversão Elétrica/métodos , Eletrodos Implantados , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , VeiasRESUMO
Whether the safety and efficacy of implantable cardioverter defibrillator (ICD) therapy can be assured with lower output devices is an important question. The purpose of this study was to evaluate whether programming the device output at twice the augmented defibrillation threshold was as safe and effective as using the maximum energy. Patients indicated for ICD therapy, but without slow monomorphic ventricular tachycardia (MVT), who achieved an augmented defibrillation threshold (DFT plus) < or = 15 joules (J) with a single endocardial lead system and a biphasic defibrillator were included in the study. Prior to ICD implantation, patients were randomized into 2 groups. The shock energies in test group patient were set as follows: first shock at twice DFT plus, the second to fifth shocks at maximum output (34 J). In control group patients, all shocks were programmed at 34 J. The study population consisted of 166 consecutive patients (mean age 57.4 +/- 12.1 years, mean left ventricular ejection fraction 36.8 +/- 13.8%). Mean DFT plus was 9.6 +/- 3.2 J in test group patients and 10.1 +/- 3.5 J in control group patients (p = 0.36). During a mean follow-up of 24.2 +/- 9.6 months, 736 arrhythmia episodes were analyzed. The first shock efficacy was 98.3% in the test group patients versus 97.4% in the control group (p = 0.45). Total mortality was 6%, equally distributed in both study groups. The results of this study prove that the method of doubling the defibrillation energy at the DFT plus level provides an adequate safety margin in defibrillator therapy.
Assuntos
Desfibriladores Implantáveis , Eletrocardiografia , Software , Taquicardia Ventricular/terapia , Fibrilação Ventricular/terapia , Adulto , Idoso , Segurança de Equipamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida , Taquicardia Ventricular/mortalidade , Resultado do Tratamento , Fibrilação Ventricular/mortalidadeRESUMO
OBJECTIVE: The relation of activins (dimers of the beta-subunits of inhibin) and follistatin (FS) (their binding protein) affect the growth and differentiation of many cell types. Activin- and FS-mRNAs show a widespread co-expression throughout the organism, indicating an essential role for the FS/activin system in diverse physiological processes. The present study was performed to investigate FS-, activin betaA-, and activin beta B-mRNA expression in porcine tissues and to compare the relative mRNA tissue distribution by a newly developed multiplex S1 nuclease protection assay. METHODS: Twenty micrograms total RNA from different porcine tissues were subjected to multiplex S1 analysis. Specific mRNA expression was determined by measurements of optical densities on autoradiographs. RESULTS: Activin beta A-mRNA expression was abundant in the ovary, adrenal gland, fat, vein, artery and uterus, activin beta B-mRNA was highly expressed in the ovary, pituitary, uterus, placenta, aorta and cerebellum. FS-mRNA showed a widespread expression with high levels in ovary, uterus, cerebellum, placenta and fat. The comparison of relative activin beta A-, activin beta B- and FS-mRNA expression within a certain tissue showed a predominance of activin beta A-mRNA in the adrenal gland, fat, artery, spinal cord, cerebrum and colon and of activin beta B-m RNA in pituitary, testis and placenta, while FS-mRNA levels exceeded those of activin subunits in epididymis, liver, lymphoid tissue, muscle, intestine, cerebellum, ovary and uterus. CONCLUSIONS: The presented data provide an overview of FS-, activin beta A-, and activin beta B-mRNA steady state levels in porcine tissues.
Assuntos
Glicoproteínas/biossíntese , Substâncias de Crescimento/biossíntese , Inibinas/biossíntese , RNA Mensageiro/análise , Endonucleases Específicas para DNA e RNA de Cadeia Simples/análise , Ativinas , Animais , Folistatina , Glicoproteínas/genética , Substâncias de Crescimento/genética , Inibinas/genética , Reação em Cadeia da Polimerase/métodos , Sondas RNA , Suínos , Distribuição Tecidual , Transcrição Gênica , LevedurasRESUMO
OBJECTIVE: Follistatin (FS) is the specific binding protein of activin and expression of both factors is regulated by inflammatory agents. Therefore, FS concentrations were determined in cerebrospinal fluid (CSF) of patients with bacterial and viral meningitis or multiple sclerosis (MS), as well as in the CSF of patients without meningial inflammation or autoimmune diseases. Furthermore, a mouse pneumococcal meningitis model was used to localise the cellular sources of FS in brains of normal and meningitic mice. METHODS: FS concentrations in CSF were determined by ELISA; FS in mice was localised by in situ hybridisation and immunohistochemistry. RESULTS: FS concentrations were > or =0.4 microg/l in 22 of 66 CSF samples of meningitis patients versus 2 of 27 CSF samples from patients with multiple sclerosis (P<0.05) and 2 of 41 CSF specimen from patients without neuroinflammatory diseases (P<0.01). In the CSF of patients with meningitis, the concentration of FS was correlated with total protein (P<0.005) and lactate concentrations (P<0.05), but not with leukocyte counts, interval between onset of disease and CSF analysis, or clinical outcome. The CSF-to-serum ratios of FS and albumin also correlated significantly (P<0.0005). In some patients with meningitis the CSF-to-serum ratios suggested that the elevated FS in CSF did not originate from serum alone. FS was localised in mice brains to neurones of the hippocampus, dentate gyrus, neocortex, and to the choroid plexus. Analyses of brains and other organs from uninfected and infected animals sacrificed 6-36 h after infection did not reveal any obvious differences in the distribution and intensity of FS mRNA and protein expression. CONCLUSIONS: The concentration of FS in humans is elevated during meningitis. In some patients the increase is caused by a release of FS from brain into CSF. Data from the mouse meningitis model suggest that increased CSF concentrations of FS in meningitis appear not to be accompanied by an elevated number of cells containing FS mRNA or protein in the brain.
Assuntos
Glicoproteínas/líquido cefalorraquidiano , Glicoproteínas/genética , Meningites Bacterianas/líquido cefalorraquidiano , Meningite Viral/líquido cefalorraquidiano , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Folistatina , Regulação da Expressão Gênica , Glicoproteínas/sangue , Substâncias de Crescimento/sangue , Substâncias de Crescimento/líquido cefalorraquidiano , Substâncias de Crescimento/genética , Humanos , Masculino , Meningites Bacterianas/sangue , Meningite Pneumocócica/sangue , Meningite Pneumocócica/líquido cefalorraquidiano , Meningite Viral/sangue , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/sangue , Esclerose Múltipla/líquido cefalorraquidiano , Valores de Referência , Streptococcus pneumoniaeRESUMO
Tumor-necrosis-factor alpha (TNF-alpha) is a major mediator of the inflammatory immune response and may play an important role in the pathogenesis and progression of Multiple Sclerosis (MS). Increased TNF-alpha levels of cerebrospinal fluid (CSF) and peripheral blood were found in patients with chronic progressive MS and patients with acute relapses, but not in the stable form of the disease. Considering the association of different TNF-alpha alleles with diverse autoimmune diseases we sequenced the TNF-alpha promotor region (-674 to +201) of 23 patients with relapsing/remitting MS, of 27 patients with chronic progressive MS (21 patients had primary progressive course and six patients had a secondary progressive course) and of 22 healthy controls, who had no history of MS in their families. In three of 21 patients (14%) with primary chronic progressive MS a homozygous point-mutation at position -308 could be demonstrated where guanine (G) was substituted by adenosine (A). This mutation could neither be detected in patients with relapsing/remitting MS nor in healthy controls. However, 40% of the patients with relapsing/remitting MS and 43% of the primary chronic progressive MS patients were heterozygous at position -308 for G/A, whereas only 32% of healthy controls showed this heterogeneity. The genetic variations were demonstrated by polymerase chain reaction (PCR)-amplification of the TNF-alpha promotor-region and consecutive direct automatic sequencing. Functional analysis of the promoter region using the chloramphenicol-acetyltransferase (CAT) assay revealed spontaneous production with the homozygous mutation at -308 only.
Assuntos
Esclerose Múltipla/genética , Polimorfismo Genético , Fator de Necrose Tumoral alfa/genética , Adenosina , Adulto , Alelos , Clonagem Molecular , Éxons , Feminino , Regulação da Expressão Gênica/fisiologia , Guanina , Humanos , Complexo Principal de Histocompatibilidade/genética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/metabolismo , Mutação Puntual/genética , Regiões Promotoras Genéticas/genética , Análise de Sequência de DNA , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Immunohistological analysis of tissue sections from human brain revealed that intercellular adhesion molecule-1 (ICAM-1) is mainly expressed on endothelial cells of small vessels, including the subependymal vessels of the choroid plexus. In addition, it is expressed on cerebrospinal fluid (CSF) cells in patients with inflammatory diseases of the central nervous system. Stimulation of confluent monolayers of adult human cerebral endothelial cells with lipopolysaccharide (LPS) or recombinant human tumor necrosis factor-alpha (TNF-alpha) could induce expression and secretion of soluble ICAM-1 in a dose dependent manner. In addition, sICAM-1 was also present in the supernatant from U251 glioma cells. No sICAM was detected in the culture supernatant from activated blood or CSF lymphocytes. Cerebral endothelial cells are therefore a likely source for sICAM-1 in the CSF.
Assuntos
Química Encefálica/fisiologia , Encéfalo/citologia , Molécula 1 de Adesão Intercelular/biossíntese , Sequência de Bases , Células Cultivadas , Endotélio/citologia , Endotélio/metabolismo , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Molécula 1 de Adesão Intercelular/líquido cefalorraquidiano , Dados de Sequência MolecularRESUMO
OBJECTIVES: The effect of implantable cardioverter/defibrillator (ICD) lead placement in the right ventricle (RV) on defibrillation efficacy has not been thoroughly investigated. Therefore, the goal of this combined experimental and clinical study was to evaluate the effect of a septal and a non-septal position of the right ventricular endocardial spring lead on defibrillation energy. METHODS: In 12 isoflurane-anaesthetized swine and subsequently in 8 patients who underwent ICD implantation, two different positions of the distal spring lead in the RV were investigated in randomized order: non-septal position (free wall of the RV) and septal position (interventricular septum). For each position, separate 50% probability determinations of energy (E50), peak voltage (V50) and peak current (A50) were calculated using the three reversal up/down defibrillation procedure. The E50, V50, A50 and impedance (I) were averaged and compared using the two-sided t-test for paired samples. RESULTS: Both the experimental study and the clinical study demonstrated that placing the distal defibrillation lead near to the septum rather than near to the ventricular free wall resulted both in the swine and in the patients in significantly lower E50-31.6%/ - 37.1%, V50-16.1%/-20.9% and A50 -10.0%/ - 24.2%, respectively. Defibrillation impedances were significantly reduced only in the experimental study. CONCLUSIONS: Defibrillation efficacy depends on the position of the distal spring electrode in the RV. A septal position significantly reduces the energy requirements compared to a non-septal position. The decrease in energy requirements might be explained by an increase in current flow through the septum and the posterolateral wall of the left ventricle. reserved