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1.
Nature ; 544(7649): 202-206, 2017 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-28346938

RESUMO

Recent observations have revealed massive galactic molecular outflows that may have the physical conditions (high gas densities) required to form stars. Indeed, several recent models predict that such massive outflows may ignite star formation within the outflow itself. This star-formation mode, in which stars form with high radial velocities, could contribute to the morphological evolution of galaxies, to the evolution in size and velocity dispersion of the spheroidal component of galaxies, and would contribute to the population of high-velocity stars, which could even escape the galaxy. Such star formation could provide in situ chemical enrichment of the circumgalactic and intergalactic medium (through supernova explosions of young stars on large orbits), and some models also predict it to contribute substantially to the star-formation rate observed in distant galaxies. Although there exists observational evidence for star formation triggered by outflows or jets into their host galaxy, as a consequence of gas compression, evidence for star formation occurring within galactic outflows is still missing. Here we report spectroscopic observations that unambiguously reveal star formation occurring in a galactic outflow at a redshift of 0.0448. The inferred star-formation rate in the outflow is larger than 15 solar masses per year. Star formation may also be occurring in other galactic outflows, but may have been missed by previous observations owing to the lack of adequate diagnostics.

2.
Phys Rev Lett ; 122(10): 101102, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30932663

RESUMO

During its orbit around the four million solar mass black hole Sagittarius A* the star S2 experiences significant changes in gravitational potential. We use this change of potential to test one part of the Einstein equivalence principle: the local position invariance (LPI). We study the dependency of different atomic transitions on the gravitational potential to give an upper limit on violations of the LPI. This is done by separately measuring the redshift from hydrogen and helium absorption lines in the stellar spectrum during its closest approach to the black hole. For this measurement we use radial velocity data from 2015 to 2018 and combine it with the gravitational potential at the position of S2, which is calculated from the precisely known orbit of S2 around the black hole. This results in a limit on a violation of the LPI of |ß_{He}-ß_{H}|=(2.4±5.1)×10^{-2}. The variation in potential that we probe with this measurement is six magnitudes larger than possible for measurements on Earth, and a factor of 10 larger than in experiments using white dwarfs. We are therefore testing the LPI in a regime where it has not been tested before.

3.
Allergy ; 71(7): 944-56, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26850094

RESUMO

BACKGROUND: Accumulation of activated eosinophils in tissue is a hallmark of allergic inflammation. The endocannabinoid 2-arachidonoylglycerol (2-AG) has been proposed to elicit eosinophil migration in a CB2 receptor/Gi/o -dependent manner. However, it has been claimed recently that this process may also involve other mechanisms such as cytokine priming and the metabolism of 2-AG into eicosanoids. Here, we explored the direct contribution of specific CB2 receptor activation to human and mouse eosinophil effector function in vitro and in vivo. METHODS: In vitro studies including CB2 expression, adhesion and migratory responsiveness, respiratory burst, degranulation, and calcium mobilization were conducted in human peripheral blood eosinophils and mouse bone marrow-derived eosinophils. Allergic airway inflammation was assessed in mouse models of acute OVA-induced asthma and directed eosinophil migration. RESULTS: CB2 expression was significantly higher in eosinophils from symptomatic allergic donors. The selective CB2 receptor agonist JWH-133 induced a moderate migratory response in eosinophils. However, short-term exposure to JWH-133 potently enhanced chemoattractant-induced eosinophil shape change, chemotaxis, CD11b surface expression, and adhesion as well as production of reactive oxygen species. Receptor specificity of the observed effects was confirmed in eosinophils from CB2 knockout mice and by using the selective CB2 antagonist SR144528. Of note, systemic application of JWH-133 clearly primed eosinophil-directed migration in vivo and aggravated both AHR and eosinophil influx into the airways in a CB2 -specific manner. This effect was completely absent in eosinophil-deficient ∆dblGATA mice. CONCLUSION: Our data indicate that CB2 may directly contribute to the pathogenesis of eosinophil-driven diseases. Moreover, we provide new insights into the molecular mechanisms underlying the CB2 -mediated priming of eosinophils. Hence, antagonism of CB2 receptors may represent a novel pharmacological approach for the treatment of allergic inflammation and other eosinophilic disorders.


Assuntos
Alérgenos/imunologia , Eosinófilos/imunologia , Eosinófilos/metabolismo , Pneumonia/etiologia , Pneumonia/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Animais , Biomarcadores , Cálcio/metabolismo , Canabinoides/farmacologia , Degranulação Celular/imunologia , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Eosinófilos/efeitos dos fármacos , Feminino , Expressão Gênica , Humanos , Hipersensibilidade/genética , Hipersensibilidade/imunologia , Hipersensibilidade/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Toxina Pertussis/imunologia , Pneumonia/patologia , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/genética , Quinases Associadas a rho/metabolismo
4.
Transpl Infect Dis ; 17(6): 880-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26437122

RESUMO

Clonorchiasis is a cholangiopathy caused by foodborne trematode parasites, also known as liver flukes. Clonorchiasis is endemic in a wide geographical area extending from Eastern Europe to Southeast Asia. Infested hosts may remain asymptomatic for decades and consequently their liver can become available as a graft. To date, 20 liver transplantations with liver fluke-infested grafts have been reported in the literature. All of them occurred in Asian countries. We, here, report the first case to our knowledge in the Western world of living-donor liver transplantation (LDLT) with an Opisthorchis felineus-infested graft, and present a review of the literature. A 6-month-old girl with decompensated secondary biliary cirrhosis underwent an LDLT with a left lateral graft infested with O. felineus. After prompt diagnosis and adequate therapy, both donor and recipient had an uneventful postoperative course and long-term follow-up. Liver grafts infested with liver flukes do not pose a contraindication to liver donation from deceased or living donors, provided that a correct diagnosis and treatment are performed in a timely fashion.


Assuntos
Fasciola hepatica , Fasciolíase/transmissão , Transplante de Fígado/efeitos adversos , Doadores Vivos , Adulto , Animais , Feminino , Humanos , Lactente
5.
Herz ; 39(1): 98-104, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23649317

RESUMO

Moderate persistent elevation of the γ-glutamyltransferase (γGT) level is a frequent finding during long-term follow-up of patients with total cavopulmonary connection (TCPC) for palliation of functionally univentricular hearts. Serial intraindividual data revealed a significant increase in the γGT level within a minimum 4-year interval in more than 80 % of cases. The level of γGT elevation showed a significant correlation to hemodynamic parameters such as systemic ventricular end diastolic pressure and mean pulmonary artery pressure, but did not strongly correlate with duration of follow-up or other liver function parameters, which were less frequent and less impressively deranged. None of the patients had signs of synthetic dysfunction. With increasing postoperative follow-up, abnormalities of sonographic hepatic texture including increased echogenicity, inhomogeneity, or liver surface nodularity were found. All 17 patients with liver surface nodularity had a follow-up period of over 10 years. Structural abnormalities did not correlate with biochemical or hemodynamic parameters. Doppler evaluation revealed inspiratory dependence of hepatic vein flow in more than 90 % as a relevant finding after TCPC; a decrease in portal vein flow velocity was observed in many patients. Since long-term survivors after Fontan procedure are at an increased risk of cardiac hepatopathy and cirrhosis, detailed routine investigation and monitoring of hepatic morphology are needed.


Assuntos
Técnica de Fontan/efeitos adversos , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Hepatopatias/etiologia , Hepatopatias/fisiopatologia , Testes de Função Hepática , Fígado/fisiopatologia , Adolescente , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/cirurgia , Insuficiência Cardíaca/diagnóstico , Humanos , Lactente , Hepatopatias/diagnóstico , Masculino , Estudos Retrospectivos , Resultado do Tratamento
6.
J Fish Biol ; 84(1): 58-72, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24383800

RESUMO

Juvenile steelhead Oncorhynchus mykiss from a northern California Central Valley population were reared in a controlled laboratory experiment. Significantly different rates of growth were observed among fish reared under two ration treatments and three temperature treatments (8, 14 and 20°C). Wider circulus spacing and faster deposition was associated with faster growth. For the same growth rate, however, circulus spacing was two-fold wider and deposited 36% less frequently in the cold compared to the hot temperature treatment. In a multiple linear regression, median circulus spacing and water temperature accounted for 68% of the variation in observed O. mykiss growth. These results corroborate previous research on scale characteristics and growth, while providing novel evidence that highlights the importance of water temperature in these relationships. Thus, this study establishes the utility of using scale analysis as a relatively non-invasive method for inferring growth in salmonids.


Assuntos
Oncorhynchus mykiss/crescimento & desenvolvimento , Temperatura , Animais , California , Modelos Lineares , Oncorhynchus mykiss/anatomia & histologia , Água
7.
Clin Nutr ESPEN ; 62: 247-252, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38857151

RESUMO

AIMS: To report the results and successes of intestinal transplantation (ITx) in the most active European centres, to emphasize that, although it is a difficult procedure, it should remain a therapeutic option for children with total, definitive and complicated intestinal failure when intestinal rehabilitation fails. METHODS: We retrospectively collected data about all patients less than 18 receiving an ITx from 2010 to 2022 in 8 centres, and outcomes in July 2022. RESULTS: ITx was performed in 155 patients, median age 6.9 years, in 45% for short bowel syndromes, 22% congenital enteropathies, 25% motility disorders, and 15% re-transplantations. Indications were multiple in most patients, intestinal failure-associated liver disease in half. The graft was in 70% liver-containing. At last follow up 64% were alive, weaned from parenteral nutrition, for 7.9 years; 27% had died and the graft was removed in 8%, mostly early after ITx. DISCUSSION: ITx, despite its difficulties, can give a future to children with complicated intestinal failure. It should be considered among the therapeutic options offered to patients with a predicted survival rate lower than that after ITx. Patients should be early discussed within multidisciplinary teams in ITx centres, to avoid severe complications impacting the results of ITx, or even to avoid ITx.


Assuntos
Intestinos , Humanos , Estudos Retrospectivos , Criança , Masculino , Feminino , Intestinos/transplante , Pré-Escolar , Lactente , Resultado do Tratamento , Adolescente , Insuficiência Intestinal , Síndrome do Intestino Curto/cirurgia , Enteropatias/cirurgia , Europa (Continente) , Nutrição Parenteral
8.
Pediatr Transplant ; 17(7): 694-706, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24004351

RESUMO

Controlled trials of mTOR inhibitors in children following solid organ transplantation are scarce, although evidence from prospective single-arm studies is growing. Everolimus with reduced CNI therapy has been shown to be efficacious and safe in de novo pediatric kidney transplant patients in prospective trials. Prospective and retrospective data in children converted from CNI therapy to mTOR inhibition following kidney, liver, or heart transplantation suggest preservation of immunosuppressive efficacy. Good renal function has been maintained when mTOR inhibitors are used de novo in children following kidney transplantation or after conversion to mTOR inhibition with CNI minimization. mTOR inhibition with reduced CNI exposure is associated with a low risk for developing infection in children. Growth and development do not appear to be impaired during low-dose mTOR inhibition, but more studies are required. No firm conclusions can be drawn as to whether mTOR inhibitors should be discontinued in children requiring surgical intervention or whether mTOR inhibition delays progression of hepatic fibrosis after pediatric liver transplantation. In conclusion, current evidence suggests that use of mTOR inhibitors in children undergoing solid organ transplantation is efficacious and safe, but a number of issues remain unresolved and further studies are required.


Assuntos
Inibidores de Calcineurina , Transplante de Coração , Imunossupressores/administração & dosagem , Transplante de Rim , Transplante de Fígado , Serina-Treonina Quinases TOR/antagonistas & inibidores , Criança , Everolimo , Fibrose/patologia , Humanos , Fígado/patologia , Transtornos Linfoproliferativos/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Risco , Sirolimo/administração & dosagem , Sirolimo/análogos & derivados , Resultado do Tratamento , Cicatrização
9.
J Exp Med ; 171(5): 1567-79, 1990 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-2185329

RESUMO

Non-MHC-restricted killer cells are cytotoxic lymphocytes that can mediate cytolysis of most tumor targets without apparent selectivity and restriction by the MHC, particularly when activated with IL-2. These effector cells include predominantly NK cells and T cells expressing the TCR-gamma/delta. We found that TCR-gamma/delta-1+, delta TSC1-, BB3+, Ti gamma A+ T cell clones mediate a characteristic cytolytic pattern of non-MHC-restricted cytolysis that is markedly different from NK clones and alpha/beta T cell clones derived from the peripheral blood of the same normal individuals. The characteristic finding is that all BB3/Ti gamma A+ gamma/delta clones mediate strong cytolysis of Daudi cells but they do not lyse Raji cells. In contrast, NK clones from the same donors mediate strong cytolysis of both Daudi and Raji targets. Cytotoxicity by the gamma/delta clones on certain target cells such as Daudi and Molt 4 can be specifically inhibited by mAbs reactive against the TCR-gamma/delta. Therefore, the TCR-gamma/delta on these clones either directly recognizes target epitopes on some tumor targets or it is involved in the regulation of their cytotoxic function. The expression of TCR-gamma/delta products reacting with the BB3 and Ti gamma A mAbs reflects the usage of identical TCR-gamma/delta V region genes that appear to be associated with the characteristic pattern of non-MHC-restricted cytotoxicity displayed by this major subset of human peripheral blood gamma/delta cells.


Assuntos
Citotoxicidade Imunológica , Células Matadoras Naturais/imunologia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/imunologia , Anticorpos Monoclonais , Complexo Antígeno-Anticorpo , Antígenos CD/análise , Linhagem Celular , Células Clonais , Imunofluorescência , Humanos , Complexo Principal de Histocompatibilidade , Fenótipo
10.
Radiologe ; 50(11): 982-90, 2010 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-20945146

RESUMO

Digital breast tomosynthesis (DBT) is a new image processing technique based on digital mammography technology. Image slices of the stationary compressed breast are reconstructed from multiple images taken at different angles of the X-ray tube at the same time. The main goal is to achieve a similar radiation dose exposure as common encountered in traditional digital mammography. One of the key advantages of DBT is that lesions are less likely to be hidden amongst normal tissues as they are in traditional digital mammography. This way the quality of diagnosis can be improved, especially for dense breasts. Current DBT implementations from several manufacturers differ in certain features such as scanning angle, number of projections, scanning time, pixel size, reconstruction methods and type of tube movement. A comparison and description of these different characteristics as well as a discussion on the proposed number of imaging planes and related radiation dose requirements are given.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Mamografia/instrumentação , Intensificação de Imagem Radiográfica/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Desenho de Equipamento , Feminino , Humanos , Doses de Radiação , Sensibilidade e Especificidade
11.
Radiologe ; 50(11): 999-1007, 2010 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-20945148

RESUMO

In Europe one out of every nine women suffers from breast cancer during her lifetime. Since the introduction of mammography screening programs more breast cancers are being diagnosed when they are still small and early stage cancers with a favourable prognosis. The introduction of digital mammography systems has led to a continuous reduction of breast cancer mortality especially in specific patient subgroups. Furthermore, the digital mammography platform enables the development of new, innovative breast imaging methods to increase sensitivity and decrease breast cancer mortality. This digital mammography platform includes digital breast tomosynthesis, digital contrast medium mammography and digital contrast medium breast tomosynthesis as well as fused data sets from digital mammography with ultrasound or MRI. The following article summarizes these new applications, describes the strengths of the digital platform and illustrates the potential advantages of an improved breast cancer diagnosis by digital mammography.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Mamografia/instrumentação , Programas de Rastreamento/instrumentação , Intensificação de Imagem Radiográfica/instrumentação , Absorciometria de Fóton/instrumentação , Adulto , Idoso , Neoplasias da Mama/mortalidade , Carcinoma Ductal de Mama/mortalidade , Carcinoma Intraductal não Infiltrante/mortalidade , Meios de Contraste/administração & dosagem , Diagnóstico Precoce , Desenho de Equipamento , Feminino , Humanos , Aumento da Imagem/instrumentação , Imageamento por Ressonância Magnética/instrumentação , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Técnica de Subtração/instrumentação , Taxa de Sobrevida , Tomografia Computadorizada por Raios X/instrumentação
12.
Allergy ; 64(9): 1319-26, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19243362

RESUMO

BACKGROUND: The basophil activation test (BAT) is a widely validated and reliable tool especially for the diagnosis of hymenoptera venom allergy. Nevertheless, several pitfalls have to be considered and outcomes may differ because of diverse in-house protocols and commercially available kits. We aimed to identify the factors that may influence results of the CD63-based BAT. METHODS: Basophil responses to monoclonal anti-IgE (clone E124.2.8) and bee and wasp venom were determined by BAT based on CD63. The effect of stimulating factors such as, IL-3, cytochalasin B and prewarming of the samples was investigated. Furthermore, we compared two different flow cytometer systems and evaluated the influence of storage time, different staining protocols and anti-allergic drugs on the test results. RESULTS: Interleukin-3 enhanced the reactivity of basophils at 300 pM, but not at 75 and 150 pM. Prewarming of samples and reagents did not affect basophil reactivity. CD63 expression assayed after storage time of up to 48 h showed that basophil reactivity already started to decline after 4 h. Basophils stained with HLA-DR-PC5 and CD123-PE antibodies gated as HLA-DR(neg)/CD123(pos) cells showed the highest reactivity. No effect on test outcomes was observed at therapeutic doses of dimetindene and desloratadine. Finally, slight differences in the percentage of activated basophils, depending on the cytometer system used, were found. CONCLUSION: Basophil activation test should be performed as early as possible after taking the blood sample, preferably within 4 h. In contrast to the skin test, BAT can be performed in patients undergoing treatment with antihistamines. For reasons of multiple influencing factors, BAT should be performed only at validated laboratories.


Assuntos
Antígenos CD/imunologia , Basófilos/imunologia , Himenópteros/imunologia , Hipersensibilidade/diagnóstico , Glicoproteínas da Membrana de Plaquetas/imunologia , Animais , Anticorpos Anti-Idiotípicos/farmacologia , Basófilos/efeitos dos fármacos , Venenos de Abelha/farmacologia , Dimetideno/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Humanos , Testes Imunológicos , Interleucina-3/farmacologia , Loratadina/análogos & derivados , Loratadina/farmacologia , Tetraspanina 30 , Venenos de Vespas/farmacologia
13.
Science ; 250(4985): 1269-73, 1990 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-1978758

RESUMO

All human gamma delta T cells coexpressing the products of the variable (V) region T cell receptor (TCR) gene segments V gamma 9 and V delta 2 recognize antigens from mycobacterial extracts and Daudi cells. Exogenous and endogenous ligands on the cell surface, homologous to the groEL heat shock family, induced reactivities that resembled superantigen responses in this major subset of human peripheral blood gamma delta T cells. Stimulation of human V gamma 9/V delta 2 T cells is not restricted by human leukocyte antigens (HLA), including nonpolymorphic beta 2-microglobulin (beta 2M)-associated class Ib molecules. These data may be important for understanding the role of gamma delta T cells in autoimmunity and in responses to microorganisms and tumors.


Assuntos
Antígenos de Bactérias/imunologia , Antígenos de Neoplasias/imunologia , Proteínas de Bactérias/imunologia , Linfoma de Burkitt/imunologia , Proteínas de Choque Térmico/imunologia , Linfócitos T/imunologia , Células Apresentadoras de Antígenos/imunologia , Chaperonina 60 , Células Clonais/imunologia , Escherichia coli/imunologia , Expressão Gênica , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Cadeias delta de Imunoglobulina/genética , Cadeias delta de Imunoglobulina/imunologia , Cadeias gama de Imunoglobulina/genética , Cadeias gama de Imunoglobulina/imunologia , Técnicas de Imunoadsorção , Mycobacterium/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Células Tumorais Cultivadas
14.
J Med Chem ; 35(6): 1049-57, 1992 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-1313110

RESUMO

[(Pyridylmethyl)sulfinyl]benzimidazoles 1 (PSBs) are a class of highly potent antisecretory (H+,K+)-ATPase inhibitors which need to be activated by acid to form their active principle, the cyclic sulfenamide 4. Selective inhibitors of the (H+,K+)-ATPase in vivo give rise to the nonselective thiophile 4 solely at low pH, thus avoiding interaction with other thiol groups in the body. The propensity to undergo the acid-catalyzed transformation is dependent on the nucleophilic/electrophilic properties of the functional groups involved in the formation of 2 since this step is both rate-determining and pH-dependent. The aim of this study was to identify compounds with high (H+,K+)-ATPase inhibitory activity in stimulated gastric glands possessing acidic pH, but low reactivity (high chemical stability) at neutral pH as reflected by in vitro (Na+,K+)-ATPase inhibitory activity. The critical influence of substituents flanking the pyridine 4-methoxy substituent present in all derivatives was carefully studied. The introduction of a 3-methoxy group gave inhibitors possessing a combination of high potency, similar to omeprazole and lansoprazole, but increased stability. As a result of these studies, compound 1a (INN pantoprazole) was selected as a candidate drug and is currently undergoing phase III clinical studies.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Benzimidazóis/síntese química , Benzimidazóis/farmacologia , Piridinas/síntese química , Sulfóxidos/farmacologia , 2-Piridinilmetilsulfinilbenzimidazóis , Trifosfato de Adenosina/antagonistas & inibidores , Animais , Benzimidazóis/química , Cães , Mucosa Gástrica/efeitos dos fármacos , ATPase Trocadora de Hidrogênio-Potássio , Omeprazol/análogos & derivados , Pantoprazol , Piridinas/química , Piridinas/farmacologia , Coelhos , Relação Estrutura-Atividade
15.
Transplantation ; 61(7): 1059-61, 1996 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8623185

RESUMO

As organ donation rates decreased in Europe, the authors started a systematic approach of liver splitting in their center in 1994. During this 1-year experience, 73 cadaveric liver transplantations were performed in 66 patients. Sixteen of these transplantations were the result of split-liver transplantation (21.9% of grafts, 24.2% of patients). Patient and graft survival rates at 3 months were 81.2% and 75%, compared with 89.1% and 76.9 % for whole organs. Two modified techniques were developed, based on the technique of living related liver procurement, and applied in 10 cases. With these new techniques, patient and graft survival rates were 90% and 90%. This systematic approach allowed the total number of transplantations in our program to be maintained, despite the decrease in organ availability.


Assuntos
Transplante de Fígado/métodos , Sobrevivência de Enxerto , Humanos
16.
Aliment Pharmacol Ther ; 9(4): 363-78, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8527612

RESUMO

Inhibition of the gastric proton pump is gaining acceptance as the treatment of choice for severe gastrooesophageal reflux disease, and for treatment of duodenal and gastric ulceration. Three of these drugs are now available (omeprazole, lansoprazole and pantoprazole) and more are being developed. Proton pump inhibitors share the same core structure, but differ in terms of substituents on this core. The substitutions are able to modify some important chemical properties of the compounds. For example, pantoprazole is significantly more acid-stable than omeprazole or lansoprazole. E3810 is significantly less stable than the other compounds. We present an explantation for this finding that depends on the relative pK values for the pyridine and benzimidazole nitrogens, especially the former. Pantoprazole formulated in an enteric-coated tablet displays high bioavailability and linear pharmacokinetics whether on single or multiple dose regimens. Although all three proton pump inhibitors provide a similar chemical conversion to sulphenamides, which are highly reactive cysteine reagents, these reagents derivatize different cysteines in the extracytoplasmic or membrane domain of the pump and inhibit the pump at different rates. Whereas the differences in chemical reactivity can be explained by the solution chemistry of the compounds, selective derivatization of different cysteines on the protein argues for an involvement of pump structure in response to the presence of the proton pump inhibitor on its luminal surface. This suggests that the proton pump inhibitors, which were originally designed to take advantage of only the highly acidic space generated in the parietal cell by the production of the sulphenamide, are made even more selective by the protein they target. Pantoprazole is metabolized by a combination of phase I and phase II metabolism, and has also been shown to have a very low potential for drug interaction. Studies of acid secretion in man have shown this compound to be an effective and long lasting inhibitor of acid secretion. The pharmacodynamics explain the cumulative effect of repeated doses and maximal acid secretory capacity with a once daily dosage.


Assuntos
Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Úlcera Péptica/tratamento farmacológico , Bombas de Próton/efeitos dos fármacos , Sulfóxidos/farmacologia , Sulfóxidos/uso terapêutico , 2-Piridinilmetilsulfinilbenzimidazóis , Úlcera Duodenal/tratamento farmacológico , Inibidores Enzimáticos/química , Humanos , Modelos Moleculares , Omeprazol/análogos & derivados , Pantoprazol
17.
J Cancer Res Clin Oncol ; 112(2): 141-3, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3095330

RESUMO

To study whether fluorescent lighting at work might increase carcinogenesis, hairless mice were exposed to a bank of six 36 W standard fluorescent lamps (neutral-white) every workday for 8 h at an illuminance level of 1,000 lx. For comparison, other mice were exposed to UVB radiation or to simulated solar radiation. In experiment A the animals were irradiated for 6 weeks prior to the application of 7,12-dimethyl-benzanthracene once and--following an interval of 2 days--for 10 weeks after DMBA application. The number of blue nevi and papillomas was enhanced by exposure to all spectra 10 weeks after chemical tumor induction. In experiment B the animals were irradiated for 6 weeks prior to the transplantation of UV-induced fibrosarcoma cells from syngeneic mice into the dorsal and ventral skin. Within the following 4 months fibrosarcoma developed in the dorsal skin exposed to the fluorescent lighting and to the UVB radiation, as well as in the non-irradiated ventral skin of 10-20% of the mice. The results suggest that fluorescent lighting as used in certain work environments may increase carcinogenesis caused by other factors.


Assuntos
Fluorescência , Papiloma/etiologia , Neoplasias Cutâneas/etiologia , 9,10-Dimetil-1,2-benzantraceno , Animais , Feminino , Fibrossarcoma/imunologia , Tolerância Imunológica , Camundongos , Camundongos Pelados , Transplante de Neoplasias , Neoplasias Induzidas por Radiação/imunologia , Neoplasias Cutâneas/imunologia , Raios Ultravioleta/efeitos adversos
18.
J Cancer Res Clin Oncol ; 126(10): 549-59, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11043392

RESUMO

Over the past decades, Positron Emission Tomography has opened a new field of imaging. Nowadays, this technique is being used for diagnosing, staging disease as well as for prognostic stratification and monitoring therapy. In this respect, [18F]fluorodeoxyglucose (FdGlc) is by far the most commonly used PET agent. Many factors have been identified being responsible for a high uptake of this agent in malignancy. However, additional factors such as tumour treatment may interfere with the uptake mechanism. Knowledge of all these factors is a prerequisite for an optimal interpretation of PET studies and, consequently, for a reliable judgement of tumour status. In this article, a review is given of the factors influencing FdGlc uptake and the implications for clinical studies.


Assuntos
Fluordesoxiglucose F18/metabolismo , Compostos Radiofarmacêuticos/metabolismo , Tomografia Computadorizada de Emissão , Ciclo do Ácido Cítrico , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glicólise , Hexoquinase/metabolismo , Humanos , Mitocôndrias/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Neoplasias/metabolismo , Tomografia Computadorizada de Emissão/métodos , Regulação para Cima
19.
J Nephrol ; 11 Suppl 1: 46-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9604810

RESUMO

Preemptive isolated liver transplantation (PLTX) can cure the metabolic defect in primary hyperoxaluria type 1 (PH1) but there are no uniformally accepted recommendations concerning the timing of this transplantation procedure. We have performed PLTX successfully in 4 children (age 3-9 years) with PH1 with no mortality or morbidity due to the transplantation procedure. Plasma and urinary oxalate levels normalised rapidly and renal function remained stable including one patient with advanced chronic renal failure who showed a stable course for more than 24 months. Although treatment must be individualised in this severe metabolic disorder and PLTX has to be viewed as invasive procedure, we feel PLTX should be offered and discussed not too late in the treatment of PH1 to prevent or at least delay the progression to end stage renal disease and systemic oxalosis.


Assuntos
Hiperoxalúria Primária/cirurgia , Transplante de Fígado , Criança , Pré-Escolar , Humanos , Falência Renal Crônica/prevenção & controle , Fatores de Tempo , Resultado do Tratamento
20.
Clin Nephrol ; 46(1): 21-3, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8832145

RESUMO

Primary hyperoxaluria type 1 (PH 1) is complicated by a high rate of early end-stage renal failure (ESRF). In ESRF combined liver kidney transplantation has emerged as treatment of choice for teenagers and adults. In chronic renal failure (CRF) and for small children the situation is less clear. We report on three isolated liver transplantations and show the data of young children from the European Registry for liver transplantation in PH 1. Patient #1 developed ESRF at 3 months of age. Deficiency of alanine:glyoxylate aminotransferase proved PH 1. Progressive bone disease developed and the boy received a living related liver graft (LRLTx) at age two. Due to recurrent cholangitis kidney transplantation (KTx) is currently not feasible. Plasma oxalate decreased after LRLTx indicating correction of the metabolic defect. Patient #2 was diagnosed at the age of 14 months. He had nephrocalcinosis and hyperglycolic hyperoxaluria. Two years later he developed ESRF. At 5 years of age isolated liver transplantation was performed as a first step of therapy. Due to prolonged warm ischemia time organ function was poor. A severe bleeding complicated the course. The child died four weeks after transplantation from untreatable CMV septicemia. Patient #3 was evaluated for failure to thrive at 6 months of age. Urinary oxalate/creatinine ratio was 705 mumol/mol and gave rise to the diagnosis of PH 1. Renal failure slowly progressed to a creatinine clearance of 20 ml/min/1.73 m2 at 8 years, when liver transplantation (LTx) was performed. Four months later, GFR has not changed. Liver function and urinary oxalate/creatinine ratio are normal. Slowly deteriorating chronic renal failure can be stabilized through isolated liver transplantation and thus the rapid need for KTx will at least be delayed. Even more important, normalization of the oxalate metabolism prevents extrarenal oxalate deposits during renal failure.


Assuntos
Hiperoxalúria Primária/cirurgia , Transplante de Fígado/métodos , Criança , Evolução Fatal , Feminino , Humanos , Hiperoxalúria Primária/complicações , Hiperoxalúria Primária/metabolismo , Lactente , Falência Renal Crônica/etiologia , Falência Renal Crônica/metabolismo , Falência Renal Crônica/fisiopatologia , Masculino , Oxalatos/metabolismo , Estudos Retrospectivos
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