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1.
Eur Heart J ; 39(17): 1555-1562, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29534171

RESUMO

Aims: The cardiac and vascular late sequelae in long-term survivors of childhood cancer (CVSS)-study aimed to quantify the prevalence of cardiovascular risk factors (CVRF) and cardiovascular disease (CVD) in German childhood cancer survivors (CCS). Methods and results: In the CVSS-study (NCT02181049), 1002 CCS (age range 23-48 years) diagnosed with neoplasia prior to 15 years of age between 1980 and 1990 prospectively underwent a systematic, standardized clinical and laboratory cardiovascular screening, identical to the population-based Gutenberg Health Study (GHS) cohort. For 951 individuals, prevalences of CVRF and CVD were primarily compared to the GHS sample and to two further German population-based cohorts. Using log-binomial regression models, an increased risk for occurrence of arterial hypertension [relative risk (RR) 1.38, 95% confidence interval (95% CI 1.21-1.57)] and dyslipidaemia [RR 1.26 (95% CI 1.12-1.42)] was found. This indicates a premature occurrence compared to the general population of approximately 6 and 8 years, respectively [rate advancement period estimator, RAPhypertension 5.75 (95% CI 3.5-8.0) and RAPdyslipidaemia 8.16 (95% CI 4.4-11.9)]. Overall, no differences were observed for obesity and diabetes. Overt CVD was present in 4.5% (95% CI 3.0-6.6%) of CCS [RR 1.89 (95% CI 1.34-2.66), RAPCVD 7.9 (95% CI 4.1-11.7)], of which the most frequent entities were congestive heart failure and venous thromboembolism. Prevalences of CVRF and CVD increased with age without reaching a plateau over time. Conclusion: This large CCS screening examination revealed consistently in comparison to three population samples a considerably increased risk for premature CVD. The findings in these young adult CCS indicate a high burden of cardiovascular morbidity and mortality in the long term. Clinicaltrials. gov-Nr: NCT02181049.


Assuntos
Sobreviventes de Câncer/estatística & dados numéricos , Doenças Cardiovasculares/epidemiologia , Adulto , Idade de Início , Comorbidade , Diabetes Mellitus/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Prevalência , Fatores de Risco , Distribuição por Sexo , Fumar/epidemiologia , Adulto Jovem
2.
Clin Genet ; 94(1): 174-178, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29652076

RESUMO

As genomic sequencing expands, so does our knowledge of the link between genetic variation and disease. Deeper catalogs of variant frequencies improve identification of benign variants, while sequencing affected individuals reveals disease-associated variation. Accumulation of human genetic data thus makes reanalysis a means to maximize the benefits of clinical sequencing. We implemented pipelines to systematically reassess sequencing data from 494 individuals with developmental disability. Reanalysis yielded pathogenic or likely pathogenic (P/LP) variants that were not initially reported in 23 individuals, 6 described here, comprising a 16% increase in P/LP yield. We also downgraded 3 LP and 6 variants of uncertain significance (VUS) due to updated population frequency data. The likelihood of identifying a new P/LP variant increased over time, as ~22% of individuals who did not receive a P/LP variant at their original analysis subsequently did after 3 years. We show here that reanalysis and data sharing increase the diagnostic yield and accuracy of clinical sequencing.


Assuntos
Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/genética , Variação Genética , Genômica , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Alelos , Variações do Número de Cópias de DNA , Frequência do Gene , Testes Genéticos , Genômica/métodos , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Sequenciamento do Exoma , Sequenciamento Completo do Genoma
3.
Ann Oncol ; 27(2): 306-14, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26598546

RESUMO

BACKGROUND: ALK-negative anaplastic large cell lymphoma associated with breast implant (i-ALCL) has been recently recognized as a distinct entity. Among 43 830 lymphomas registered in the French Lymphopath network since 2010, 300 breast lymphomas comprising 25 peripheral T-cell lymphomas (PTCL) were reviewed. Among PTCL, ALK-negative ALCL was the most frequent and all of them were associated with breast implants. PATIENTS AND METHODS: Since 2010, all i-ALCL cases were collected from different institutions through Lymphopath. Immuno-morphologic features, molecular data and clinical outcome of 19 i-ALCLs have been retrospectively analyzed. RESULTS: The median age of the patients was 61 years and the median length between breast implant and i-ALCL was 9 years. Most implants were silicone-filled and textured. Implant removal was performed in 17 out of 19 patients with additional treatment based on mostly CHOP or CHOP-like chemotherapy regimens (n = 10/19) or irradiation (n = 1/19). CHOP alone or ABVD following radiation without implant removal have been given in two patients. The two clinical presentations, i.e. effusion and less frequently tumor mass correlated with distinct histopathologic features: in situ i-ALCL (anaplastic cell proliferation confined to the fibrous capsule) and infiltrative i-ALCL (pleomorphic cells massively infiltrating adjacent tissue with eosinophils and sometimes Reed-Sternberg-like cells mimicking Hodgkin lymphoma). Malignant cells were CD30-positive, showed a variable staining for EMA and were ALK negative. Most cases had a cytotoxic T-cell immunophenotype with variable T-cell antigen loss and pSTAT3 nuclear expression. T-cell receptor genes were clonally rearranged in 13 out of 13 tested cases. After 18 months of median follow-up, the 2-year overall survival for in situ and infiltrative i-ALCL was 100% and 52.5%, respectively. CONCLUSIONS: In situ i-ALCLs have an indolent clinical course and generally remain free of disease after implant removal. However, infiltrative i-ALCLs could have a more aggressive clinical course that might require additional therapy to implant removal.


Assuntos
Implantes de Mama/efeitos adversos , Linfoma Anaplásico de Células Grandes/patologia , Linfoma de Células T Periférico/patologia , Silicones/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico , Feminino , Doença de Hodgkin/patologia , Humanos , Imunofenotipagem , Antígeno Ki-1/metabolismo , Linfoma Anaplásico de Células Grandes/induzido quimicamente , Linfoma Anaplásico de Células Grandes/mortalidade , Linfoma de Células T Periférico/induzido quimicamente , Linfoma de Células T Periférico/mortalidade , Pessoa de Meia-Idade , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Estudos Retrospectivos , Fator de Transcrição STAT3/metabolismo , Linfócitos T Citotóxicos/imunologia
4.
Ann Neurol ; 78(6): 982-994, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26418456

RESUMO

OBJECTIVE: Mutations in TPM3, encoding Tpm3.12, cause a clinically and histopathologically diverse group of myopathies characterized by muscle weakness. We report two patients with novel de novo Tpm3.12 single glutamic acid deletions at positions ΔE218 and ΔE224, resulting in a significant hypercontractile phenotype with congenital muscle stiffness, rather than weakness, and respiratory failure in one patient. METHODS: The effect of the Tpm3.12 deletions on the contractile properties in dissected patient myofibers was measured. We used quantitative in vitro motility assay to measure Ca(2+) sensitivity of thin filaments reconstituted with recombinant Tpm3.12 ΔE218 and ΔE224. RESULTS: Contractility studies on permeabilized myofibers demonstrated reduced maximal active tension from both patients with increased Ca(2+) sensitivity and altered cross-bridge cycling kinetics in ΔE224 fibers. In vitro motility studies showed a two-fold increase in Ca(2+) sensitivity of the fraction of filaments motile and the filament sliding velocity concentrations for both mutations. INTERPRETATION: These data indicate that Tpm3.12 deletions ΔE218 and ΔE224 result in increased Ca(2+) sensitivity of the troponin-tropomyosin complex, resulting in abnormally active interaction of the actin and myosin complex. Both mutations are located in the charged motifs of the actin-binding residues of tropomyosin 3, thus disrupting the electrostatic interactions that facilitate accurate tropomyosin binding with actin necessary to prevent the on-state. The mutations destabilize the off-state and result in excessively sensitized excitation-contraction coupling of the contractile apparatus. This work expands the phenotypic spectrum of TPM3-related disease and provides insights into the pathophysiological mechanisms of the actin-tropomyosin complex.


Assuntos
Contração Muscular , Fibras Musculares Esqueléticas/patologia , Doenças Musculares/genética , Tropomiosina/genética , Pré-Escolar , Exoma , Feminino , Humanos , Masculino , Doenças Musculares/patologia , Doenças Musculares/fisiopatologia , Mutação , Fenótipo , Insuficiência Respiratória , Deleção de Sequência
5.
J Anim Physiol Anim Nutr (Berl) ; 93(3): 350-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19175459

RESUMO

The aim of this study was to examine whether and to what extent the addition of potassium diformate (pdf) or free organic acids (fpa) to the diet and the grinding intensity might affect the course of infection and the passage of orally applied Salmonella and Escherichia coli in pigs. Experiments were carried out using 80 reared piglets allotted to four groups. Pigs were fed pelleted diets ad libitum (except during a 15 h feed-withholding-period before infection). The control diet contained finely ground cereals (2 mm screen). To two test diets (also finely ground) 1.2% pdf, 0.9% organic acids (75% formic and 25% propionic acid, fpa) respectively were added. The fourth diet (without acids) was based on coarsely ground cereals (6-mm screen). After experimental infection alternately with S. Derby or E. coli, the course of infection was examined (rectal swab technique). Pigs were sacrificed 4-5 h after a further oral application of approximately 10(9)-10(10) CFU S. Derby or E. coli to determine the counts of Salmonella or E. coli in chyme (classical culture methods). Adding pdf or fpa to the diet led to reduced Salmonella shedding and resulted in significantly lower counts of Salmonella and E. coli in the stomach content indicating an improved efficacy of the stomach barrier. In the distal parts of the digestive tract, the effect was less obvious concerning counts of E. coli, whereas counts of Salmonella were reduced markedly as well. The diet based on coarsely ground cereals failed to demonstrate positive effects concerning infection and passage of orally applied bacteria as well, but this diet was also pelleted and showed unintentionally, comparable amounts of fine particles. Results obtained in this study allow the recommendation of using pdf or organic acids as additives when dietary measures against Salmonella or E. coli in pigs are required.


Assuntos
Dieta/veterinária , Infecções por Escherichia coli/veterinária , Compostos de Potássio/farmacologia , Salmonelose Animal/prevenção & controle , Doenças dos Suínos/prevenção & controle , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Escherichia coli , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Fezes/microbiologia , Aditivos Alimentares/administração & dosagem , Aditivos Alimentares/farmacologia , Formiatos/administração & dosagem , Formiatos/farmacologia , Conteúdo Gastrointestinal/microbiologia , Salmonella , Salmonelose Animal/microbiologia , Suínos
6.
J Mol Biol ; 231(3): 554-8, 1993 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-8515439

RESUMO

Recent X-ray crystallographic and solution X-ray scattering studies have shown that transferrins (serum transferrin, lactoferrin and ovotransferrin) undergo a major conformational change when iron is incorporated into the molecule. Apo-proteins show a structure with open interdomain clefts which close when iron is bound. The closed conformation has been suggested as an important step in the receptor recognition. Here, we report X-ray solution scattering experiments of the mutated N-terminal fragment of human serum transferrin with Asp63-->Ser (Cys). The data provide the first direct experimental evidence for the existence of a trigger mechanism for the closure of the interdomain cleft and that this trigger mechanism is disrupted by mutation of Asp63, the only ligand of iron from domain I.


Assuntos
Ácido Aspártico/metabolismo , Transferrina/metabolismo , Humanos , Ligação de Hidrogênio , Ferro/metabolismo , Ligantes , Modelos Moleculares , Mutagênese Sítio-Dirigida , Espalhamento de Radiação , Transferrina/química , Transferrina/genética , Raios X
7.
J Mol Biol ; 229(3): 585-90, 1993 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-8433360

RESUMO

Recent studies on iron-loaded transferrins have revealed a conformational change upon binding iron due to a domain closure. It has been suggested that the domain closure may be the key for the receptor recognition of the metal loaded transferrin (Grossmann et al., 1992). Small angle X-ray scattering has been used to provide direct structural information on the conformational changes that may take place upon the binding and release of different metals to the transferrins in solution. The data show that In3+ and Cu2+ induce the same domain closure as Fe3+; Al3+ causes a conformational change of somewhat smaller magnitude while Hf4+ does not induce any conformational change. The results are discussed in terms of the molecular recognition of metal loaded transferrin by the receptor.


Assuntos
Metais/química , Transferrina/química , Conformação Proteica , Espalhamento de Radiação , Soluções
8.
J Mol Biol ; 279(2): 461-72, 1998 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-9642050

RESUMO

Ligand-induced conformational change in transferrins has been studied by site-directed mutagenesis of human serum half molecule (N-lobe), X-ray absorption fine structure (XAFS) spectroscopy and X-ray solution scattering. Use of recent advances in data analysis has been made for extracting model-independent molecular shapes from X-ray solution scattering data for the intact, the half molecule and its mutants. Clear evidence is provided that the transferrin molecule (intact as well as N-lobe), in its apo and holo forms, exists for the majority of the time in well-defined specific conformations representing the "fully opened" and "closed" states of the molecule, respectively. Evidence is also provided for the existence of an additional conformation, referred to here as the "intermediate" conformation for simplicity, which is trapped in the case of some of the mutants in the iron-bound form. We suggest that domain closure in the transferrin molecule is a two-step process, with the intermediate conformation representing the first stage of domain closure (approximately 20 degrees hinge-twist of domain II). Our data are not inconsistent with the ligand-free molecule sampling the closed states occasionally (< or = 10%) but are not in support of a continuous conformational search between the fully opened and closed states in the absence of iron.


Assuntos
Transferrina/química , Animais , Sítios de Ligação/genética , Humanos , Técnicas In Vitro , Ferro/química , Ligantes , Modelos Moleculares , Mutagênese Sítio-Dirigida , Conformação Proteica , Espalhamento de Radiação , Soluções , Análise Espectral , Transferrina/genética , Raios X
9.
J Mol Biol ; 225(3): 811-9, 1992 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-1602483

RESUMO

X-ray solution scattering has been used for studying the structural changes that take place upon uptake and release of iron from serum and chicken ovo-transferrin and human lactoferrin. In the case of chicken ovo-transferrin, data have been obtained for both the intact protein and the isolated N and C-lobes with and without iron. These studies reveal that both lobes undergo a change that is consistent with an opening of the inter-domain cleft when iron is removed from the protein. We suggest that the conformational change of the protein increases the specificity of receptor binding and that the closed configuration of the iron-loaded protein is one, or perhaps the, decisive step in the mechanism for receptor-mediated endocytosis.


Assuntos
Ferro/metabolismo , Lactoferrina/ultraestrutura , Transferrina/ultraestrutura , Animais , Apoproteínas/química , Galinhas , Simulação por Computador , Humanos , Técnicas In Vitro , Lactoferrina/metabolismo , Modelos Moleculares , Movimento (Física) , Fragmentos de Peptídeos/química , Conformação Proteica , Espalhamento de Radiação , Soluções , Transferrina/metabolismo , Raios X
10.
J Control Release ; 109(1-3): 299-316, 2005 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-16298009

RESUMO

Gene therapy aimed at the respiratory epithelium holds therapeutic potential for diseases such as cystic fibrosis and lung cancer. Polyethylenimine (PEI) has been utilized for gene delivery to the airways. In this study, we describe a new modification of PEI, in which an oligopeptide related to the protein transduction domain of HIV-1 TAT was covalently coupled to 25 kDa PEI (PEI) through a heterobifunctional polyethylenglycol (PEG) spacer resulting in a TAT-PEG-PEI conjugate. Improved DNA reporter gene complexation and protection was observed for small (approximately 90 nm) polyplexes as well as significantly improved stability against polyanions, Alveofact, bronchial alveolar lining fluid and DNase. To determine polyplex toxicity in vitro, MTT assays were performed and, for in vivo testing, the mice bronchial alveolar lavage was investigated for total cell counts, quantity of neutrophils, total protein and TNF-alpha concentration. All parameters suggest significantly lower toxicity for TAT-PEG-PEI. Transfection efficiencies of both PEI and TAT-PEG-PEI polyplexes with DNA were studied under in vitro conditions (A549) and in mice after intratracheal instillation. While luciferase expression in A549 cells was much lower for TAT-PEG-PEI (0.2 ng/mg protein) than for PEI (2 ng/mg), significantly higher transfection efficiencies for TAT-PEG-PEI were detected in mice. Reporter gene expression was distributed through bronchial and alveolar tissue. Thus, TAT-PEG-PEI represents a new approach to non-viral gene carriers for lung therapy, comprising protection for plasmid DNA, low toxicity and significantly enhanced transfection efficiency under in vivo conditions.


Assuntos
DNA/administração & dosagem , Portadores de Fármacos , Produtos do Gene tat/química , Terapia Genética/métodos , Nanoestruturas , Polietilenoglicóis/química , Polietilenoimina/química , Animais , Líquido da Lavagem Broncoalveolar/química , Fenômenos Químicos , Físico-Química , Sistemas de Liberação de Medicamentos , Células Epiteliais/fisiologia , Etídio/química , Produtos do Gene tat/toxicidade , Genes Reporter/genética , Heparina/química , Humanos , Luciferases/genética , Pulmão/citologia , Pulmão/patologia , Camundongos , Ensaios de Proteção de Nucleases , Oligonucleotídeos/administração & dosagem , Distribuição Tecidual , Transfecção
11.
MMWR Suppl ; 64(2): 18-24, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25856534

RESUMO

PROBLEM/CONDITION: Persons exposed to chemicals during acute chemical incidents (i.e., uncontrolled or illegal release or threatened release of hazardous substances lasting <72 hours) can experience both acute and chronic health effects. Surveillance of toxic substance incidents provides data that can be used to prevent future incidents and improve the emergency response to those that occur, leading to a decrease in morbidity and mortality from chemical releases. REPORTING PERIOD: 1999-2008 DESCRIPTION OF SYSTEM: The Hazardous Substances Emergency Events Surveillance (HSEES) system was operated by the Agency for Toxic Substances and Disease Registry (ATSDR) during January 1991-September 2009 to describe the public health consequences of chemical releases and to develop activities aimed at reducing the harm. This report summarizes the data collected on injured persons from the nine states (Colorado, Iowa, Minnesota, New York, North Carolina, Oregon, Texas, Washington, and Wisconsin) that participated in HSEES during its last 10 full years of data collection (1999-2008). RESULTS: A total of 57,975 chemical incidents were reported by these states during the 10-year surveillance period. In 4,621 (8%) of these incidents, 15,506 persons were injured. Among them, 354 deaths occurred. The most commonly reported category of injured persons included employees of the responsible party (7,616 [49%]), members of the general public (4,737 [31%]), students exposed at school (1,730 [11%]), and responders to the incident (1,398 [9%]). Deaths occurred among members of the general public (190 [54%]), employees (154 [44%]), and responders (10 [3%]). The most frequent health effects experienced as a result of these incidents included respiratory irritation (7,443), dizziness or central nervous system problems (3,186), and headache (3,167). The three chemicals associated with the largest number of persons injured were carbon monoxide (2,364), ammonia (1,153), and chlorine (763). INTERPRETATION: Company employees, followed by members of the general public, are frequently injured in acute chemical incidents. The chemicals most often associated with these injuries are carbon monoxide, ammonia, and chlorine, all of which are hazardous gases that can be found in various locations including schools and homes. Respiratory irritation is the most common health effect. PUBLIC HEALTH IMPLICATIONS: By understanding the types of persons injured in chemical release incidents, as well as how they are injured and the injuries sustained, prevention outreach activities can be focused to protect the health of these groups in the future. Improved awareness among and training for not just employees but also the public is needed, particularly regarding carbon monoxide, ammonia, and chlorine. Appropriate measures to provide protection from respiratory effects of chemical incidents could prevent injuries.


Assuntos
Vazamento de Resíduos Químicos/estatística & dados numéricos , Vigilância da População , Ferimentos e Lesões/induzido quimicamente , Humanos , Estados Unidos/epidemiologia , Ferimentos e Lesões/epidemiologia
12.
Transplantation ; 59(2): 218-23, 1995 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-7839443

RESUMO

We report the first series of 9 auxiliary liver transplantations performed as a bridge to recovery in 8 patients with fulminant and subfulminant hepatic failure. Hepatic failure was due to hepatitis A virus (n = 3), hepatitis B virus (n = 1), hepatotoxic drugs (n = 2), autoimmune disease (n = 1), or it was of unknown origin (n = 1). The donor liver was reduced to a left lobe (n = 2), a left liver (n = 4), or a right liver (n = 3), and was implanted in an orthotopic position beside the native liver after it was resected by a left or a right hepatectomy. Conventional immunosuppression was used to prevent rejection. Six patients regained normal consciousness within 2 weeks, without any sequelae. Two patients had persisting encephalopathy due to graft initial dysfunction, one of whom showed portal vein thrombosis, which was successfully cleared. The other one showed hepatic vein stenosis and was retransplanted at day 15. Five of eight patients had to be reoperated because of a surgical complication. Five patients showed rapid regeneration of their native liver, but one died at day 45 from severe herpes virus broncholitis. The auxiliary grafts were removed (n = 3) or left to atrophy by tapering immunosuppression (n = 1). One patient developed cirrhosis of the native liver and died of infectious complications at day 42. The native livers of the two remaining patients are still atrophic, one at 4 months and one at 1 month posttransplant. Finally, 6 of 8 patients are alive with a follow-up of 1 to 17 months. Four of them have permanently stopped their immunosuppressive therapy. Our experience demonstrates that auxiliary orthotopic liver transplantation (1) is feasible in children and adults, using either a left or a right liver graft, (2) is efficient in providing adequate liver function, and (3) gives a real chance to the native liver to regenerate, offering these patients a future free of immunosuppression.


Assuntos
Encefalopatia Hepática/cirurgia , Transplante de Fígado , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Fígado/fisiologia , Regeneração Hepática , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório
13.
Transplantation ; 71(12): 1731-5, 2001 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-11455250

RESUMO

BACKGROUND: In a pig liver transplantation model, we compared the effects of Celsior solution (CS), an extracellular preservation solution, with Viaspan (University of Wisconsin solution, UW) on graft function and animal survival. METHODS: Pig livers were flushed with either CS or UW solution and cold-stored for 12 hr (group 1) or for 8 to 10 hr (group 2). Grafts were transplanted orthotopically. Intrahepatic reduced and oxidized glutathione and adenine nucleotides were evaluated 1 hr after reperfusion. Liver function of transplanted animals was monitored for up to 6 days by serum transaminases, total bilirubin, purine nucleoside phosphorylase, and prothrombin levels. RESULTS: In group 1, all animals died within 24 hr after reperfusion regardless of the preservation solution used. In group 2, no significant difference was seen in survival between the CS (72%) and the UW (67%) groups 6 days after transplantation, and there were no statistically significant differences in the biochemical data. There were no differences in histological evaluation of the livers at the time of death or killing of the animals between the CS and UW groups. CONCLUSION: Within the limits of this pilot study, CS is equivalent to UW in terms of graft function and animal survival.


Assuntos
Adenosina/farmacologia , Alopurinol/farmacologia , Dissacarídeos/farmacologia , Eletrólitos/farmacologia , Glutamatos/farmacologia , Glutationa/farmacologia , Histidina/farmacologia , Insulina/farmacologia , Transplante de Fígado , Manitol/farmacologia , Soluções para Preservação de Órgãos/farmacologia , Rafinose/farmacologia , Animais , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/fisiopatologia , Análise de Sobrevida , Suínos , Transplante Heterotópico
14.
Transpl Immunol ; 6(1): 13-22, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9640624

RESUMO

Organ perfusion is one of the possible strategies to attenuate rejection of discordant xenografts by reducing the levels of the recipient's xenoreactive natural antibodies (XNA). Its efficacy in terms of XNA removal was studied in models of primate blood or plasma perfusion through porcine kidneys or livers, with special attention to haematological consequences and potential side-effects. We first perfused the blood of rhesus monkeys through pig kidneys and livers, and demonstrated that the perfusion of a pig liver resulted in higher XNA adsorption (72 +/- 13%) than the perfusion of a pig kidney (51 +/- 25%). However, when we normalized for the weight of the perfused organs and for levels of natural antibodies in individual monkeys, livers adsorbed less antibody (1.4 +/- 0.9 U antibody/g) than kidneys (7.2 +/- 7 U antibody/g). Histological signs of rejection were observed in perfused kidneys, but not in perfused livers. A major drawback of the perfusion of blood through livers was a considerable decrease in the primates' haemoglobin and platelet levels. To avoid this, we developed a plasma liver perfusion device. This method allowed a significant improvement in the haemodynamic state of primates and was particularly effective in preventing anaemia. Moreover, plasma liver perfusion was as effective as blood liver perfusion to remove natural antibodies and, resulted in a marked decrease in their functional activity as assessed by complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC). The level of other plasma proteins was not significantly affected, apart from a dilution effect. After xenoperfusion a strong antibody response was evidenced by ELISA, CDC and ADCC between days 7 and 14 and then decreased progressively. We conclude that the separation of blood to allow the perfusion of plasma through a pig organ is safer than the perfusion of unseparated blood and is associated with efficient natural antibody removal. However, organ perfusion is limited by a rebound in antibody levels after a few days, and thus will have to be associated with anti-B cell immunosuppressive therapy for long-term or repeated applications.


Assuntos
Anticorpos Heterófilos , Transplante de Rim/imunologia , Rim/imunologia , Fígado/imunologia , Animais , Anticorpos Heterófilos/isolamento & purificação , Citotoxicidade Celular Dependente de Anticorpos , Células Epiteliais , Circulação Extracorpórea , Hemodinâmica , Imunoglobulina M/sangue , Macaca mulatta , Perfusão , Suínos , Transplante Heterólogo
15.
Cell Transplant ; 10(1): 67-80, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11294474

RESUMO

Banking of cryopreserved hepatocytes is a prerequisite for large-scale hepatocyte transplantation in the clinic. We compared the efficacy of intrasplenic transplantation into Nagase analbuminemic rats (NAR) of freshly isolated (FIH) and cryopreserved (CH) hepatocytes. Hepatocytes were cryopreserved using a controlled rate freezing protocol. Albumin production of thawed CH and FIH was measured in vitro in culture by ELISA and by Western blot. After in vivo intrasplenic transplantation of NAR with either FIH or CH we assessed 1) albumin in the serum of recipients by ELISA and by Western blotting analysis at different time intervals, and 2) hepatocyte engraftment by albumin immunohistochemical staining into spleens and livers at euthanasia. In vitro, albumin was produced up to day 4 of culture in both CH and FIH. In vivo, no intrasplenic engraftment of hepatocytes occurred. Intrahepatic engraftment of CH (cell number/mm2) was significantly (twofold) lower than that of FIH and appeared only as isolated cells and small (<10 cells) clusters, while bigger clusters (>10 cells) were observed with FIH. In the FIH group, serum albumin production was observed up to 32-49 days posttransplantation while in the CH group no serum albumin production was detected. Our results emphasize the need to improve 1) hepatocyte transplantation procedures either by repeated hepatocytes injections and/or by transplantation under a regeneration response, and 2) the freeze/thaw protocols of hepatocytes.


Assuntos
Transplante de Células/métodos , Hepatócitos/transplante , Albumina Sérica/deficiência , Animais , Separação Celular , Células Cultivadas , Criopreservação , Sobrevivência de Enxerto , Hepatócitos/patologia , Humanos , Técnicas In Vitro , Masculino , Ratos , Ratos Sprague-Dawley , Albumina Sérica/biossíntese , Baço/patologia , Baço/cirurgia
16.
Clin Neurophysiol ; 110(11): 1935-41, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10576490

RESUMO

Based on a consecutive series of 70 hearing patients with unilateral acoustic neurinomas and intraoperative monitoring of brain-stem auditory evoked potentials (BAEP), 4 dynamic BAEP patterns could be characterized. These patterns correspond with early and late postoperative hearing outcome. All patients with stable wave V (pattern 1) showed definite hearing preservation, all patients with irreversible abrupt loss of BAEP (pattern 2) lost their hearing, despite early hearing preservation in two cases. All patients with irreversible progressive loss of either wave I or wave V (pattern 3) eventually suffered from definite postoperative hearing loss, despite early hearing preservation in two cases. Those cases with intraoperative reversible loss of BAEP (pattern 4) showed variable short and long term hearing outcome. In 34% hearing was preserved, 44% suffered from postoperative hearing loss, the remaining 22% showed postoperative hearing fluctuation, either as a delayed hearing loss or as reversible hearing loss. Postoperative hearing fluctuation indicates anatomical and functional preservation of the cochlear nerve during surgery and is suggestive of a pathophysiological mechanism initiated during the surgical procedure and continuing thereafter. Patients at risk for delayed hearing loss can be identified during surgery by a characteristic BAEP pattern and may benefit from vasoactive treatment.


Assuntos
Neoplasias da Orelha/cirurgia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Neuroma Acústico/cirurgia , Audiometria de Tons Puros , Audiometria da Fala , Nervo Coclear/fisiopatologia , Surdez/etiologia , Neoplasias da Orelha/complicações , Neoplasias da Orelha/fisiopatologia , Humanos , Monitorização Intraoperatória , Neuroma Acústico/complicações , Neuroma Acústico/fisiopatologia , Prognóstico , Fatores de Tempo
17.
Neurosurgery ; 48(5): 1157-9; discussion 1159-61, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11334285

RESUMO

IMPORTANCE: Preservation of venous drainage during surgery of the cerebellopontine angle has received little attention. CLINICAL PRESENTATION: We describe changes in brainstem auditory evoked potentials after temporary obstruction of the superior petrosal vein during surgical resection of a small meningioma at the petrous apex via a standard suboccipital-lateral approach. Temporary clipping of the petrosal vein resulted in deterioration of the brainstem auditory evoked potentials. The tumor was removed with preservation of the superior petrosal vein. CONCLUSION: A transient postoperative cochlear nerve deficit emphasizes the importance of venous drainage and its preservation during surgery for small lesions of the cerebellopontine angle that do not distort normal anatomic structures.


Assuntos
Ângulo Cerebelopontino/cirurgia , Nervo Coclear/fisiopatologia , Constrição , Potenciais Evocados Auditivos do Tronco Encefálico , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Osso Petroso/irrigação sanguínea , Feminino , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Fatores de Tempo , Veias/fisiopatologia
18.
J Neurosurg ; 95(5): 771-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11702866

RESUMO

OBJECT: Delayed hearing loss following surgery for acoustic neuroma indicates anatomical and functional preservation of the cochlear nerve and implies that a pathophysiological mechanism is initiated during surgery and continues thereafter. Intraoperative brainstem auditory evoked potentials (BAEPs) typically demonstrate gradual reversible loss of components in these patients. METHODS: Based on this BAEP pattern, a consecutive series of 41 patients with unilateral acoustic neuromas was recruited into a prospective randomized study to investigate hearing outcomes following the natural postoperative course and recuperation after vasoactive medication. Both groups were comparable in patient age, tumor size, and preoperative hearing level. Twenty patients did not receive postoperative medical treatment. In 70% of these patients anacusis was documented and in 30% hearing was preserved. Twenty-one patients were treated with hydroxyethyl starch and nimodipine for an average of 9 days. In 66.6% of these patients hearing was preserved and in 33.3% anacusis occurred. CONCLUSIONS: These results are statistically significant (p < 0.05, chi2 = 5.51) and provide evidence that these surgically treated patients suffer from a disturbed microcirculation that causes delayed hearing loss following removal of acoustic neuromas.


Assuntos
Audição , Derivados de Hidroxietil Amido/uso terapêutico , Neuroma Acústico/tratamento farmacológico , Neuroma Acústico/cirurgia , Nimodipina/uso terapêutico , Substitutos do Plasma/uso terapêutico , Cuidados Pós-Operatórios , Vasodilatadores/uso terapêutico , Adulto , Idoso , Surdez/etiologia , Potenciais Evocados Auditivos do Tronco Encefálico , Humanos , Pessoa de Meia-Idade , Neuroma Acústico/fisiopatologia , Complicações Pós-Operatórias , Período Pós-Operatório , Estudos Prospectivos , Resultado do Tratamento
19.
Am J Surg ; 182(1): 81-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11532423

RESUMO

BACKGROUND: In spite of many reports focusing on prognostic factors after hepatectomy in patients with colorectal liver metastases, few studies have investigated pathological factors, eg, fibrous pseudocapsulation, growth pattern at the tumor margin, and proliferation activity of cancer cells, other than histological type and surgical margin. The aim of the present study was to investigate whether absence of pseudocapsulation, infiltrative growth pattern of metastases, and higher proliferation of cancer cells shown by Ki-67 immunohistochemical reactivity were associated with poorer survival after hepatectomy among patients with colorectal liver metastases. METHODS: Between 1988 and 1998, 221 patients underwent hepatic resection of colorectal metastases with curative intent in our institution. Pathology analyses were focused on pseudocapsulation of liver metastases, growth pattern at the tumor edge, and Ki-67 labelling index (Ki-67 LI) of cancer cell nuclei. Univariate analyses of survival and of disease-free survival were performed for several clinicopathological factors, and multivariate analyses of survival and disease-free survival were also performed. RESULTS: The univariate survival analyses showed that pseudocapsulation, growth pattern, and Ki-67 LI were significant prognostic factors, besides synchronous versus metachronous occurrence of metastases, carcinoembryonic antigen level before hepatectomy, and number of metastases. A multivariate analysis showed that Ki-67 labeling index was the most reliable prognostic factor of survival. In addition, Ki-67 LI and microscopic growth pattern were multivariately predictive factors of disease-free survival. CONCLUSIONS: This large single-institution study showed that investigation of cancer cell proliferation and pathologic characteristics of the tumor margin are major prognostic factors.


Assuntos
Neoplasias Colorretais/patologia , Hepatectomia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Análise de Variância , Biomarcadores Tumorais/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Antígeno Ki-67/metabolismo , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica/patologia , Valor Preditivo dos Testes , Prognóstico , Taxa de Sobrevida
20.
J Musculoskelet Neuronal Interact ; 4(1): 105-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15615084

RESUMO

Bone densitometric data often are difficult to interpret in children and adolescents because of large inter- and intraindividual variations in bone size. Here, we propose a functional approach to bone densitometry that addresses two questions: Is bone strength normally adapted to the largest physiological loads, that is, muscle force? Is muscle force adequate for body size? To implement this approach, forearm muscle cross-sectional area (CSA) and bone mineral content (BMC) of the radial diaphysis were measured in 349 healthy subjects from 6 to 19 years of age (183 girls), using peripheral quantitative computed tomography (pQCT). This functional approach to pediatric bone densitometric data should be adaptable to a variety of densitometric techniques.


Assuntos
Absorciometria de Fóton/métodos , Desenvolvimento Ósseo/fisiologia , Osso e Ossos/fisiologia , Músculo Esquelético/fisiologia , Esqueleto , Absorciometria de Fóton/normas , Adolescente , Adulto , Densidade Óssea/fisiologia , Osso e Ossos/anatomia & histologia , Osso e Ossos/diagnóstico por imagem , Criança , Feminino , Humanos , Masculino , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Suporte de Carga/fisiologia
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