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1.
Appl Environ Microbiol ; 87(20): e0083221, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34378953

RESUMO

Iron-bearing minerals are key components of the Earth's crust and potentially critical energy sources for subsurface microbial life. The Deep Mine Microbial Observatory (DeMMO) is situated in a range of iron-rich lithologies, and fracture fluids here reach concentrations as high as 8.84 mg/liter. Iron cycling is likely an important process, given the high concentrations of iron in fracture fluids and detection of putative iron-cycling taxa via marker gene surveys. However, a previous metagenomic survey detected no iron cycling potential at two DeMMO localities. Here, we revisited the potential for iron cycling at DeMMO using a new metagenomic data set including all DeMMO sites and FeGenie, a new annotation pipeline that is optimized for the detection of iron cycling genes. We annotated functional genes from whole metagenomic assemblies and metagenome-assembled genomes and characterized putative iron cycling pathways and taxa in the context of local geochemical conditions and available metabolic energy estimated from thermodynamic models. We reannotated previous metagenomic data, revealing iron cycling potential that was previously missed. Across both metagenomic data sets, we found that not only is there genetic potential for iron cycling at DeMMO, but also, iron is likely an important source of energy across the system. In response to the dramatic differences we observed between annotation approaches, we recommend the use of optimized pipelines where the detection of iron cycling genes is a major goal. IMPORTANCE We investigated iron cycling potential among microbial communities inhabiting iron-rich fracture fluids to a depth of 1.5 km in the continental crust. A previous study found no iron cycling potential in the communities despite the iron-rich nature of the system. A new tool for detecting iron cycling genes was recently published, which we used on a new data set. We combined this with a number of other approaches to get a holistic view of metabolic strategies across the communities, revealing iron cycling to be an important process here. In addition, we used the tool on the data from the previous study, revealing previously missed iron cycling potential. Iron is common in continental crust; thus, our findings are likely not unique to our study site. Our new view of important metabolic strategies underscores the importance of choosing optimized tools for detecting the potential for metabolisms like iron cycling that may otherwise be missed.


Assuntos
Ferro/metabolismo , Microbiota/genética , Bactérias , Fenômenos Geológicos , Metagenoma , Metagenômica , RNA Ribossômico 16S , South Dakota
2.
Eur J Vasc Endovasc Surg ; 54(3): 295-302, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28754428

RESUMO

PURPOSE: Report mid-term outcomes of thoracic endovascular aneurysm repair (TEVAR) with chimney and periscope grafts (CPG) in supra-aortic branches (SAB). METHODS: Retrospective analysis, from October 2009 to May 2014, of patients with aneurysms requiring TEVAR with zone 0/1/2 proximal landing in association with at least one CPG in the SAB. All patients were considered at high risk for conventional surgery. Peri-operative mortality and morbidity, retrograde type A dissection, maximum aortic transverse diameter (TD) and its post-operative evolution, endoleak, survival, freedom from cardiovascular re-interventions, and CPG freedom from occlusion during the follow-up were analysed. RESULTS: Forty-one patients (28.05% EuroScore II) with thoraco-abdominal aortic aneurysm (17%), arch aneurysm (39%), descending aneurysm (34%), and aneurysm extending from the arch to the visceral aorta (10%) were included. Fifteen (37%) patients were treated non-electively. Fifty-nine SABs were treated with the CPG technique: one, two, three, and four CPG were employed in 71%, 19%, 5%, and 5% of patients, respectively. The proximal landing was in zone 0 in 49% of patients, zone 1 in 17%, and zone 2 in 34%. Technical success was 95%. Peri-operative complications and neurological events were registered in six (14.6%) patients and there were 5 deaths (12%). At a median follow-up of 21.2 (mean 22, SD 18; range 0-65) months, type I/III endoleaks were registered in three (7%) cases and re-intervention in six (15%) patients. A significant aneurysm sac shrinkage (p<.001) was reported at mean follow-up and no significant aneurysm sac increase (>5 mm). The estimated 2 year survival, freedom from re-intervention, freedom from endoleak, and freedom from branch occlusion were 75%, 77%, 86%, and 96%, respectively. CONCLUSION: The chimney and periscope grafts technique was shown to be safe in aortic aneurysm disease involving the supra aortic branches, even in an emergency setting using off the shelf devices. Mid-term follow-up results in this high risk population are good, but longer follow-up is mandatory before this technique is used in intermediate-risk patients.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/mortalidade , Aortografia/métodos , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Angiografia por Tomografia Computadorizada , Intervalo Livre de Doença , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Complicações Pós-Operatórias/etiologia , Desenho de Prótese , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
3.
Transplant Proc ; 47(9): 2791-4, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26680097

RESUMO

Renal transplantation in HIV-positive patients with end-stage renal disease has in recent years become a successful treatment option. We report two patients who underwent renal transplantation using a combination of basiliximab, calcineurin inhibitors, mycophenolate mofetil (MMF), and steroids with a "non-interacting" antiretroviral combination therapy consisting of stavudine or abacavir, lamivudine, and nevirapine. We observed no acute rejection but a BK polyomavirus infection in both patients. In conclusion, a quadruple immunosuppression with an interleukin 2 receptor antagonist, a calcineurin inhibitor, MMF, and steroids appears to be advisable to prevent high rates of acute rejection, but if possible thereafter immunosuppression should be tapered rapidly (eg, MMF stop, prednisolone dose 5 mg/d). The selection of antiretroviral agents should avoid compounds that interact severely with the immunosuppression used.


Assuntos
Rejeição de Enxerto/prevenção & controle , Infecções por HIV/tratamento farmacológico , Imunossupressores/uso terapêutico , Falência Renal Crônica/cirurgia , Transplante de Rim , Adulto , Anticorpos Monoclonais/uso terapêutico , Basiliximab , Inibidores de Calcineurina/uso terapêutico , Quimioterapia Combinada , Feminino , Hospitais Universitários , Humanos , Rim/efeitos dos fármacos , Rim/virologia , Falência Renal Crônica/virologia , Masculino , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Prednisolona/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Esteroides/uso terapêutico
4.
Neuroscience ; 290: 398-405, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25639231

RESUMO

Research on motor imagery and action observation has become increasingly important in recent years particularly because of its potential benefits for movement rehabilitation and the optimization of athletic performance (Munzert et al., 2009). Motor execution, motor imagery, and action observation have been shown to rely largely on a similar neural network in motor and motor-related cortical areas (Jeannerod, 2001). Given that motor imagery is a covert stage of an action and its characteristics, it has been assumed that modifying the motor task in terms of, for example, effort will impact neural activity. With this background, the present study examined how different force requirements influence corticospinal excitability (CSE) and intracortical facilitation during motor imagery and action observation of a repetitive movement (dynamic force production). Participants were instructed to kinesthetically imagine or observe an abduction/adduction movement of the right index finger that differed in terms of force requirements. Trials were carried out with single- or paired-pulse transcranial magnetic stimulation. Surface electromyography was recorded from the first dorsal interosseous (FDI) and the abductor digiti minimi (ADM). As expected, results showed a significant main effect on mean peak-to-peak motor-evoked potential (MEP) amplitudes in FDI but no differences in MEP amplitudes in ADM muscle. Participants' mean peak-to-peak MEPs increased when the force requirements (movement effort) of the imagined or observed action were increased. This reveals an impact of the imagined and observed force requirements of repetitive movements on CSE. It is concluded that this effect might be due to stronger motor neuron recruitment for motor imagery and action observation with an additional load. That would imply that the modification of motor parameters in movements such as force requirements modulates CSE.


Assuntos
Imaginação/fisiologia , Percepção de Movimento/fisiologia , Córtex Motor/fisiologia , Músculo Esquelético/fisiologia , Tratos Piramidais/fisiologia , Adulto , Eletromiografia , Potencial Evocado Motor/fisiologia , Feminino , Mãos/fisiologia , Humanos , Masculino , Estimulação Magnética Transcraniana
5.
J Phys Condens Matter ; 26(45): 456003, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25336527

RESUMO

We investigate the effect of electric current pulse injection on domain walls in La(0.7)Sr(0.3)MnO(3) (LSMO) half-ring nanostructures by high resolution x-ray magnetic microscopy at room temperature. Due to the easily accessible Curie temperature of LSMO, we can employ reasonable current densities to induce the Joule heating necessary to observe effects such as hopping of the domain walls between different pinning sites and nucleation/annihilation events. Such effects are the dominant features close to the Curie temperature, while spin torque is found to play a small role close to room temperature. We are also able to observe thermally activated domain wall transformations and we find that, for the analyzed geometries, the vortex domain wall configuration is energetically favored, in agreement with micromagnetic simulations.


Assuntos
Lantânio/química , Fenômenos Magnéticos , Compostos de Manganês/química , Microscopia , Nanoestruturas/química , Óxidos/química , Estrôncio/química , Condutividade Elétrica , Temperatura , Raios X
7.
J Cell Physiol ; 229(12): 1946-51, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24710763

RESUMO

In female mammals, granulosa cells of the ovarian follicle differentiate into the corpus luteum after ovulation of the pregnable oocyte into the fallopian tube. During these differentiation processes several morphological alterations have to occur and the molecular basis is not fully understood. As an endpoint estradiol production from granulosa cells has to switch off in favor for progesterone production from the proceeding corpus luteum to sustain the developing embryo. Previously, we demonstrated that the multiligand receptor LOX-1 plays a critical role in steroid hormone synthesis of granulosa cells via intracellular calcium release from endoplasmic (ER)-dependent and ER-independent calcium pools. In the present study, we show that inhibition of LOX-1 leads to a rearrangement of ceramide from the basal membrane toward the Golgi apparatus. This activity is accomplished by a calcium-dependent phosphorylation of aromatase, the key step in estradiol production. Phosphorylated aromatase increased estradiol production in a dose-dependent manner. Our data indicate that the ceramide cascade is essential for proper granulosa cell function and ceramide redistribution serves as a first step in order to proceed with the prosperous differentiation into a corpus luteum.


Assuntos
Diferenciação Celular/genética , Desenvolvimento Embrionário/genética , Oócitos/citologia , Receptores Depuradores Classe E/genética , Animais , Bovinos , Ceramidas/metabolismo , Corpo Lúteo/citologia , Corpo Lúteo/metabolismo , Feminino , Hormônio Foliculoestimulante/metabolismo , Complexo de Golgi/genética , Células da Granulosa/citologia , Células da Granulosa/metabolismo , Humanos , Oócitos/crescimento & desenvolvimento , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo , Receptores Depuradores Classe E/antagonistas & inibidores , Transdução de Sinais
8.
Waste Manag ; 34(2): 390-401, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24252370

RESUMO

In firing systems of cement production plants and coal-fired power plants, regular fossil fuels are increasingly substituted by alternative fuels. Rising energy prices and ambitious CO2-reduction goals promote the use of alternative fuels as a significant contribution to efficient energy recovery. One possibility to protect energy resources are refuse-derived fuels (RDF), which are produced during the treatment of municipal solid, commercial and industrial waste. The waste fractions suitable for RDF have a high calorific value and are often not suitable for material recycling. With current treatment processes, RDF still contains components which impede the utilization in firing systems or limit the degree of substitution. The content of these undesired components may amount to 4 wt%. These, in most cases incombustible particles which consist of mineral, ceramic and metallic materials can cause damages in the conveying systems (e. g. rotary feeder) or result in contaminations of the products (e. g. cement, chalk). Up-to-date separation processes (sieve machine, magnet separator or air classifier) have individual weaknesses that could hamper a secure separation of these particles. This article describes a new technology for the separation of impurities from refuse derived fuels based on a rotating fluidized bed. In this concept a rotating motion of the particle bed is obtained by the tangential injection of the fluidization gas in a static geometry. The RDF-particles experience a centrifugal force which fluidized the bed radially. The technical principle allows tearing up of particle clusters to single particles. Radially inwards the vertical velocity is much lower thus particles of every description can fall down there. For the subsequent separation of the particles by form and density an additionally cone shaped plate was installed in the centre. Impurities have a higher density and a compact form compared to combustible particles and can be separated with a high efficiency. The new technology was experimentally investigated and proven using model-RDF, actual-RDF and impurities of different densities. In addition, numerical simulations were also done. The fluidization chamber was operated in batch mode. The article describes experiences and difficulties in using rotating fluidized bed systems.


Assuntos
Fontes Geradoras de Energia/estatística & dados numéricos , Indústrias/métodos , Modelos Teóricos , Material Particulado/análise , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Alemanha , Indústrias/economia , Tamanho da Partícula , Pressão
9.
Cytometry A ; 85(1): 88-93, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24115745

RESUMO

Estradiol produced by ovarian granulosa cells triggers the luteinizing hormone surge which in turn initiates ovulation in female mammals. Disturbances in estradiol production from granulosa cells are a major reason for reproductive dysfunctions in dairy cows. Endogenous estradiol production might be altered by reactive oxygen species (ROS) such as oxidized low-density lipoprotein (ox-LDL). Inhibition of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), a receptor of ox-LDL, leads to increased estrogenesis in granulosa cells. This activity is mediated by calcium release from endoplasmic reticulum (ER)-dependent and ER-independent calcium pools. Inhibition of the LOX-1 signal transduction pathway is followed by mitochondrial alterations. The membrane potential ΔΨ increases and the ROS production decreases in mitochondria after blocking LOX-1. Our data indicate that blocking the LOX-1 receptor signal pathway might be a promising way to improve steroid hormone concentrations in metabolically highly active female mammals and, therefore, to defend against reproductive dysfunctions in humans and animals.


Assuntos
Cálcio/metabolismo , Estradiol/biossíntese , Ovulação/metabolismo , Receptores Depuradores Classe E/genética , Animais , Bovinos , Feminino , Células da Granulosa/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Hormônio Luteinizante/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores Depuradores Classe E/antagonistas & inibidores , Receptores Depuradores Classe E/metabolismo , Transdução de Sinais/genética
10.
Comp Exerc Physiol ; 10(2): 75-88, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-28680481

RESUMO

In vertebrates ageing is characterized by reduced viscoelasticity of the ligamentous and tendineous structures and fibre changes in muscle. Also, some vertebral joint degeneration develops with ageing. The aim of this study was to apply dynamic time warping to compare the temporal characteristics of the surface electromyography (sEMG) data and to illustrate the differences in the pattern of muscle use during tasks of daily life in old and mature horses. In vivo kinematics (24 skin markers) and sEMG measurements of neck extensors and flexors were taken in five mature horses (age 10 ± 2 years, half of mean life expectancy) and five old horses (age 25 ± 5 years, older than the mean life expectancy). All horses had the same level of activity in the 12 months prior to the measurement. Tasks measured were neck flexion and neck extension as well as neutral neck position. Muscle activation, minimum and maximum muscle activation were collected. Quartiles of muscle activity based on the maximum observed activity of each muscle were calculated to document the relative increase of activity level during the task. Kinematics as well as overall muscle activity patterns were similar across horses and age groups. However, in the neutral position old horses showed increased extensor activity compared to mature horses, indicating that old equine muscle requires more activity to counteract gravity. Dynamic time warping specified optimal temporal alignments of time series, and different temporal performances were identified. The age groups differed during the flexion task, while extension and neutral were more similar. The results of this study show that even in the second half of life and in the absence of muscle disuse the muscular strategy employed by horses continues to be adapted.

11.
Transplant Proc ; 45(4): 1503-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23726606

RESUMO

BACKGROUND: A shift from anti- to proinflammatory steroid hormones has been observed in chronic inflammation. We tested the hypothesis that this shift occurs also in kidney transplant rejection together with a rise of urinary catecholamine degradation product concentrations as a consequence of locally produced cytokines, thus further promoting rejection. METHODS: We examined 8 patients with an early rejection episode in the protocol biopsy ∼2 weeks, 9 with biopsy-proven rejection at 2-3 months, and 18 without rejection, both at 2 weeks and 3 months after transplantation. Metanephrine, normetanephrine, and 2- and 16-hydroxyestrogens concentrations were measured by EIA. RESULTS: The median urinary concentrations of normetanephrine, but not metanephrine, were significantly higher in acute kidney transplant rejection in the first 2 weeks after transplantation (P < .05). During acute kidney transplant rejection at 2-3 months, but not in the first 2 weeks, after transplantation, 2-, but not 16-hydroxyestrogens, concentrations were significantly decreased (P < .05). CONCLUSIONS: We demonstrated that the downstream product of noradrenaline conversion normetanephrine was elevated in kidney transplant rejection in the first weeks after transplantation. This change may promote rejection together with an important proinflammatory and mitogenic steroid hormone shift, which becomes increasingly relevant over time.


Assuntos
Estrogênios/urina , Rejeição de Enxerto/urina , Transplante de Rim , Normetanefrina/urina , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Dtsch Med Wochenschr ; 137(38): 1873-7, 2012 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-22971974

RESUMO

Acute kidney injury (AKI) of any origin is a common complication/disease in hospitalized patients, going along with significantly increased mortality and morbidity, as well as hospitalization duration and expenses. Drug-induced AKI is usually seen in patients with concurrent risk factors such as existing kidney disease, dehydration with or without hypotension, older age or diabetes mellitus. In cases with multiple risk factors or therapies the triggering drug is often impossible to define. Hemodynamic alterations, intrinsic tubulointerstitial damages and intrarenal (i. e. tubular) obstructions as a result of drug precipitations are the pathophysiological basis of this disease entity. Clinically the AKI is perceived as the most important problem, due to the development of hyperhydration (including pulmonary edema) and reduced/lacking clearance of toxic metabolites. The prognosis of drug-induced AKI is usually good, especially if the agents are stopped early in the process, but nevertheless some patients experience severe acute AKI requiring dialysis with/without subsequent restoration. Considering and recognizing potential risk factors may help to identify patients at risk and lead to introduction of prophylactic actions. Identification of risk factors and the introduction of prevention strategies should be an integral part of everybody's daily clinical work, especially in intensive care medicine due to the high susceptibility to AKI.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/terapia , Anti-Inflamatórios não Esteroides/efeitos adversos , Comorbidade , Meios de Contraste/efeitos adversos , Diagnóstico Diferencial , Substituição de Medicamentos , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Rim/efeitos dos fármacos , Necrose do Córtex Renal/induzido quimicamente , Necrose do Córtex Renal/terapia , Testes de Função Renal , Edema Pulmonar/induzido quimicamente , Diálise Renal , Fatores de Risco , Resultado do Tratamento
15.
Am J Physiol Gastrointest Liver Physiol ; 299(4): G877-86, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20671193

RESUMO

Endoplasmic reticulum (ER) stress leads to accumulation of un- or misfolded proteins inside the ER and initiates the unfolded protein response (UPR). Several UPR components are physiologically involved in pancreatic development and are pathophysiologically activated during acute pancreatitis. However, the exact role of ER stress in exocrine pancreatic acini is mainly unclear. The present study examined the effects of tauroursodeoxycholic acid (TUDCA), a known ER chaperone, on acinar function and UPR components. Isolated rat pancreatic acini were stimulated by increasing concentrations of cholecystokinin (CCK-8) with or without preincubation of TUDCA. UPR components were analyzed, including chaperone binding protein (BiP), protein kinase-like ER kinase (PERK), X-box binding protein (XBP)-1, c-Jun NH(2)-terminal kinase (JNK), CCAAT/enhancer binding protein homologues protein (CHOP), caspase 3 activation, and apoptosis. In addition, TUDCA effects were measured on amylase secretion, calcium signaling, trypsin, and cathepsin B activation. TUDCA preincubation led to a significant increase in amylase secretion after CCK-8 stimulation, a 50% reduction of intracellular trypsin activation, and reduced cathepsin B activity, although the effects for cathepsin B were not statistical significant. Furthermore, TUDCA prevented the CCK-8-induced BiP upregulation, diminished PERK and JNK phosphorylation, and prohibited the expression of CHOP, caspase 3 activation and apoptosis. XBP-1 splicing was not altered. ER stress response mechanisms are activated in pancreatic inflammation. Chemical chaperones enhance enzyme secretion of pancreatic acini, reduce ER stress responses, and attenuate ER stress-associated apoptosis. These data hint new perspectives for an employment of chemical chaperones in the therapy of acute pancreatitis.


Assuntos
Retículo Endoplasmático/efeitos dos fármacos , Pâncreas/citologia , Pâncreas/efeitos dos fármacos , Ácido Tauroquenodesoxicólico/farmacologia , Tripsina/metabolismo , Amilases/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Catepsina B/metabolismo , Colagogos e Coleréticos/farmacologia , Relação Dose-Resposta a Droga , Retículo Endoplasmático/fisiologia , Ativação Enzimática , Pâncreas/metabolismo , Ratos , Estresse Fisiológico
16.
Immunol Lett ; 127(2): 119-25, 2010 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-19879295

RESUMO

Toll-like receptors (TLRs) provide an important link between innate and adaptive immune system. We hypothesized that the recognition of endogenous TLR4 ligands is occurring at the time of transplantation, and these innate signals drive the inflammation and affect alloimmune responses. We confirmed that early after transplantation of allogenic islets, transcripts for TLR4 as well as potential ligands were released or up-regulated. In an allogenic islet transplantation model, genetic disruption of TLR4 on donor islets had no effect on allograft survival, whereas TLR4 deficiency in recipients lead to prolonged graft survival. Low dose rapamycin-treatment of TLR4(-/-) recipients induced permanent engraftment of 45% islet graft (p=0.005) compared to WT recipients. This prolonged graft survival was dependent on the presence of CD4(+)CD25(+)Foxp3(+) Treg. Naïve CD4(+)CD25(-) T cells cultured with the TLR4 ligand lipopolysaccharide showed enhanced IL-4, IL-6, IL-17, IFN gamma secretion and inhibited TGFbeta induced Foxp3(+)Treg generation. Thus, inhibition of recipient TLR4 activation at the time of transplantation decreases proinflammatory signals and allows Treg generation.


Assuntos
Rejeição de Enxerto/imunologia , Transplante das Ilhotas Pancreáticas , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Antígenos CD4/biossíntese , Citocinas/metabolismo , Fatores de Transcrição Forkhead/biossíntese , Rejeição de Enxerto/genética , Sobrevivência de Enxerto , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Fator de Crescimento Transformador beta/imunologia , Tolerância ao Transplante , Transplante Homólogo/imunologia , Transplante Homólogo/patologia
17.
Transplant Proc ; 41(6): 2539-43, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19715970

RESUMO

BACKGROUND: At present, inflammation is considered to be one of the key players in the development and maintenance of atherosclerosis, with ample impact on renal transplant outcomes. Interleukin-6 (IL-6) levels and the underlying genetically determined "high-producer" status impact cardiovascular morbidity and mortality. In end-stage renal disease (ESRD) patients, the role of genetically determined IL-6 differences in cardiovascular and renal outcomes of kidney transplantation is controversial. In this study, we sought to clarify the influence of IL-6 haplotypes on cardiovascular and renal outcomes among kidney transplant recipients. METHODS: Three hundred fifty-two first kidney transplant patients were genotyped for the two "clade" IL-6 polymorphisms ((-174)G/C and (1888)G/T) and two missense polymorphisms (Pro32Ser, Asp162Val), which are known to influence IL-6 levels and outcome. RESULTS: We observed four IL-6 haplotypes among our population: CCAG: 57.0%, CCAT: 2.8%, GCAT: 39.2%, GCTT: 1.0%. After stratifying the haplotypes into diplotypes in three different models, we failed to observe associations with early or late graft outcomes, or with all-cause or cardiovascular mortality. These findings were also confirmed when we separately analyzed each polymorphism. CONCLUSION: Despite evidence of associations in other transplant and ESRD cohorts, we could not confirm any association between IL-6 haplotypes/diplotypes and cardiovascular or graft-related outcomes among our population at high risk for inflammatory diseases.


Assuntos
Doenças Cardiovasculares/epidemiologia , Interleucina-6/genética , Transplante de Rim/efeitos adversos , Adulto , Idoso , Doenças Cardiovasculares/genética , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Antígenos HLA/genética , Haplótipos , Teste de Histocompatibilidade , Humanos , Interleucina-6/sangue , Testes de Função Renal , Transplante de Rim/mortalidade , Transplante de Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Tempo
18.
Transplant Proc ; 41(6): 2573-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19715977

RESUMO

BACKGROUND: Modified release tacrolimus is a new, once-daily oral formulation of the established immunosuppressive agent tacrolimus. Little is known about de novo immunosuppression after simultaneous pancreas-kidney transplantation using modified release tacrolimus. METHODS: To test the feasibility of modified release tacrolimus in simultaneous pancreas-kidney transplantation (SPK), we conducted a prospective study of 14 consecutive transplants using modified release tacrolimus (Advagraf, ADV), mycophenolate mofetil, and low-dose corticosteroids as the initial immunosuppressive regimen. Patient and graft survival, the rates of acute rejection, graft function as well as ADV dosages, and trough levels (C(min)) were investigated after a mean follow-up time of 11.0 +/- 3.1 months. RESULTS: Overall patient, kidney, and pancreas graft survival were 100%, 100%, and 93%, respectively. One pancreas graft was lost owing to vascular graft thrombosis 2 days after transplantation. The incidence of rejection episodes at 11 months was 38%. ADV was well tolerated in the majority of patients. Only in 1 case tacrolimus (ADV) was stopped because of psychotic symptoms. In week 2 and 3 posttransplant, a significant adjustment in the ADV dosage was necessary to achieve sufficient tacrolimus trough levels. CONCLUSIONS: The results of this case series report demonstrate that patients after SPK can be safely treated with modified release tacrolimus. Further studies are needed to investigate pharmacokinetic profiles of modified release tacrolimus after SPK.


Assuntos
Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Transplante de Pâncreas/imunologia , Tacrolimo/uso terapêutico , Corticosteroides/uso terapêutico , Adulto , Diabetes Mellitus/cirurgia , Nefropatias Diabéticas/cirurgia , Feminino , Seguimentos , Sobrevivência de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Transplante de Rim/mortalidade , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Transplante de Pâncreas/mortalidade , Diálise Peritoneal , Estudos Prospectivos , Diálise Renal , Fatores de Tempo
19.
Clin Nephrol ; 71(5): 543-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19473615

RESUMO

BACKGROUND: Transplant renal artery stenosis (TRAS) is a frequent complication after renal transplantation, however long-term follow-up data after interventional treatment are rare. PATIENTS: In our transplant center 11 of 264 consecutive renal transplant recipients (4.17%) were diagnosed with TRAS. In addition, TRAS occurred in 2 renal transplant recipients that had been transplanted at other centers but who had their follow-up examinations in our center. Either a rise of the serum creatinine level and/or worsened systemic hypertension or routine examination with color Doppler sonography were indications for further diagnostic workup. METHODS: Direct angiography of the transplant renal artery was performed followed by percutaneous transluminal angioplasty (PTA) after the diagnosis of TRAS was confirmed in all of these patients. RESULTS: The immediate success rate for PTA was 92.3% (12/13). Only 1 patient with a severe kinking of the transplant renal artery had to undergo surgery to restore renal function. No complications occurred after the interventions. Thereafter the patients were monitored for a mean observation period of 33.15 months. Serum creatinine levels were significantly lower after the intervention, and estimated glomerular filtration rate (eGFR) increased accordingly. With regard to blood pressure there was only a trend for lower blood pressure levels and less antihypertensive use, whereas the dose of the prescribed drugs decreased significantly with time after interventional treatment of TRAS. In addition, a long-lasting rise of the hemoglobin levels could also be demonstrated. CONCLUSION: In summary, the beneficial effect of PTA of TRAS on renal function is long-lasting. Therefore, PTA, usually combined with stent placement, should be first-line treatment in TRAS in all patients. Surgical revascularization is only warranted, if PTA fails.


Assuntos
Angioplastia com Balão/métodos , Falência Renal Crônica/cirurgia , Transplante de Rim , Obstrução da Artéria Renal/terapia , Adulto , Idoso , Angiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Obstrução da Artéria Renal/diagnóstico por imagem , Obstrução da Artéria Renal/etiologia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
20.
Am J Transplant ; 9(4): 675-86, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19298452

RESUMO

An important role of TNF interacting with TNFR2 has been shown in different models of ischemic, nephrotoxic and immune-mediated renal injury. To systematically evaluate the expression of TNFR2 in renal allograft rejection, we investigated human renal allograft biopsies and, in addition, established an experimental transplantation model in rats to verify the human data under standardized conditions. The expression of TNFR2 was analyzed in 96 human renal allograft biopsies with different disease entities. In a 6-day and a 28-day experimental protocol, TNFR2 was examined in kidney specimens and in the urine of control, uni-nephrectomized and transplanted rats +/- cyclosporine treatment (n = 114). In human biopsies and in rat allografts on day 6 with acute allograft rejection, significantly elevated expression of TNFR2 was observed in tubular epithelial cells, podocytes, B cells and monocytes/macrophages. The expression level was associated with renal function. The TNFR2 expression level at day 28 was significantly lower compared to day 6. TNFR2 is markedly upregulated both in human and experimental acute renal allograft rejection. Our data are robust and consistent between different species, suggesting a role for TNFR2 in the early course of rejection.


Assuntos
Regulação da Expressão Gênica , Rejeição de Enxerto/genética , Transplante de Rim/patologia , Receptores Tipo II do Fator de Necrose Tumoral/genética , Adulto , Idoso , Animais , Biópsia , Ciclosporina/uso terapêutico , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Modelos Animais , Ratos , Receptores Tipo I de Fatores de Necrose Tumoral/fisiologia , Transplante Homólogo/patologia , Regulação para Cima
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