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1.
Am J Transplant ; 17(1): 191-200, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27375072

RESUMO

For donation after circulatory death (DCD), many centers allow 1 h after treatment withdrawal to donor death for kidneys. Our center has consistently allowed 2 h. We hypothesized that waiting longer would be associated with worse outcome. A single-center, retrospective analysis of DCD kidneys transplanted between 2008 and 2013 as well as a nationwide survey of organ procurement organization DCD practices were conducted. We identified 296 DCD kidneys, of which 247 (83.4%) were transplanted and 49 (16.6%) were discarded. Of the 247 recipients, 225 (group 1; 91.1%) received kidneys with a time to death (TTD) of 0-1 h; 22 (group 2; 8.9%) received grafts with a TTD of 1-2 h. Five-year patient survival was 88.8% for group 1, and 83.9% for group 2 (p = 0.667); Graft survival was also similar, with 5-year survival of 74.1% for group 1, and 83.9% for group 2 (p = 0.507). The delayed graft function rate was the same in both groups (50.2% vs. 50.0%, p = 0.984). TTD was not predictive of graft failure. Nationally, the average maximum wait-time for DCD kidneys was 77.2 min. By waiting 2 h for DCD kidneys, we performed 9.8% more transplants without worse outcomes. Nationally, this practice would allow for hundreds of additional kidney transplants, annually.


Assuntos
Morte Encefálica , Rejeição de Enxerto/prevenção & controle , Parada Cardíaca , Falência Renal Crônica/cirurgia , Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/métodos , Adulto , Seleção do Doador , Feminino , Seguimentos , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Hospitais com Alto Volume de Atendimentos , Humanos , Testes de Função Renal , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Prognóstico , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Estados Unidos
2.
Transplant Proc ; 48(6): 1887-92, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27569916

RESUMO

BACKGROUND: We have previously shown that approximately 27% of patients do not progress to death in time to donate organs after attempted donation after circulatory death (DCD). As such, nearly 1000 transplants per year are not possible. One way to convert unsuccessful donations to successful donations is to increase procurement team "stand-down" times; however, increased stand-down times may predispose transplantable organs to increased ischemic damage. METHODS: Hemodynamics for successful and unsuccessful donations, occurring between 2011 and 2014, were characterized to determine if some unsuccessful DCDs could have donated successfully, had procurement teams waited longer. RESULTS: Analysis of 169 DCDs demonstrated statistically significant differences in hemodynamic profiles after withdrawal of support (WOS) between successful and unsuccessful donations. Early decreases in oxygen saturation were predictive of successful organ donation. We observed that for unsuccessful DCDs, patients who died in more than 2 hours but less than 12 hours were agonal within 10 minutes of WOS, suggesting that increasing stand-down times would result in prohibitive warm ischemia time. CONCLUSIONS: Early changes in oxygen saturation after withdrawal of support predict donor death. Alternative approaches that convert unsuccessful DCDs to successful DCDs but that do not result in low-quality organs should be explored.


Assuntos
Doadores de Tecidos , Obtenção de Tecidos e Órgãos/métodos , Transplantes/irrigação sanguínea , Adulto , Morte , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Isquemia Quente
3.
Am J Transplant ; 12(1): 152-61, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21992480

RESUMO

This study investigates how college students can be social support catalysts for organ donation and how social, cognitive and attitudinal dimensions impact organ donor registration. A total of 317 people participated in the exploratory portion of the project and a total of 1800 responses were obtained from an online survey to members of a national student organization. The findings show that perceptions of the benefits of organ donation and altruistic motives had the greatest impact on the support for organ donation while respondents' knowledge about how to register to be an organ donor was the dominant dimension for donor registration status. Social-based communications had the next greatest impact for both support and donor registration. Based on the findings, an 18-month social media campaign was launched with the student organization that had 20 421 website visitors, 4473 Facebook members, 1189 YouTube video submissions with 164 000 views, motivated 19 623 people to go to a state's organ donor registration page, and had 9000 documented organ donor registrations. Within the student organization, organ donor registration increased by 28%. On the basis of these project results, Donate Life America and other sponsors have provided funding for two additional years.


Assuntos
Atitude Frente a Saúde , Cognição , Apoio Social , Estudantes/psicologia , Doadores de Tecidos/psicologia , Adolescente , Adulto , Análise Fatorial , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Inquéritos e Questionários , Universidades
4.
Am J Transplant ; 11(3): 500-10, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21342448

RESUMO

The role of humoral alloreactivity in ABO-compatible liver transplantation remains unclear. To understand the significance of donor-specific HLA alloantibodies (DSA) in liver rejection, we applied the currently used strategy for detection of antibody-mediated rejection of other solid allografts. For this purpose we reviewed the data on 43 recipients of ABO identical/compatible donor livers who had indication liver biopsy stained for complement element C4d and contemporaneous circulating DSA determination. Seventeen (40%) patients had significant circulating DSA in association with diffuse portal C4d deposition (DSA+/diffuse C4d+). These DSA+/diffuse C4d+ subjects had higher frequency of acute cellular rejection (ACR) 15/17 versus 13/26 (88% vs. 50%), p = 0.02, and steroid resistant rejection 7/17 versus 5/26 (41% vs. 19%), p = 0.03. Based on detection of the combination DSA+/diffuse C4d+, 53.6% of cases of ACR had evidence of concurrent humoral alloreactivity. Six of the 10 patients with ductopenic rejection had circulating DSA and diffuse portal C4d, three of whom (2 early and 1 late posttransplantation) developed unrelenting cholestasis, necessitating specific antibody-depleting therapy to salvage the allografts. Thus, in ABO-compatible liver transplantation humoral alloreactivity mediated by antibodies against donor HLA molecules appears to be frequently intertwined with cellular mechanisms of rejection, and to play a role in ductopenia development.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Doenças dos Ductos Biliares/etiologia , Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Isoanticorpos/sangue , Transplante de Fígado/imunologia , Doadores de Tecidos , Adolescente , Adulto , Idoso , Doenças dos Ductos Biliares/patologia , Complemento C4b/imunologia , Complemento C4b/metabolismo , Feminino , Citometria de Fluxo , Humanos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Fatores de Risco , Transplante Homólogo/imunologia , Resultado do Tratamento , Adulto Jovem
5.
Am J Transplant ; 11(3): 591-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21299836

RESUMO

Using structural equation modeling, the direct and indirect impact of five variables on the support of donation after cardiac death from the perspective of health care professionals were investigated: knowledge, trust in the transplant team, whether patients are in a state of irreversibility, whether health care professionals participate in a patient's death, and perceptions about the brain death versus cardiac death donation process. In total, 10/15 relationships posited in the model had significant pathways. The results provide insight into sequential communication strategies for generating support for donations after cardiac death.


Assuntos
Atitude do Pessoal de Saúde , Comunicação , Morte , Modelos Psicológicos , Doadores de Tecidos/psicologia , Obtenção de Tecidos e Órgãos , Morte Encefálica , Família/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Relações Profissional-Família , Inquéritos e Questionários , Fatores de Tempo
6.
Int J Immunopathol Pharmacol ; 23(3): 683-91, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20943037

RESUMO

Periodontal diseases are considered as multifactorial conditions initiated by infection with pathogenic bacteria, promoted by inflammation and immune response against bacteria and modified by different environmental and genetic factors. Recently, interest in periodontal diseases has been increasing due to the awareness that the hyperinflammatory status associated with this disorder could impose a significant increase of reactive oxygen species (ROS) relevant to numerous systemic diseases driven by a pro-oxidant profile. A highly complex interplay occurs between oxidative stress and AGEs (Advanced Glycation End products), a group of heterogeneous compounds that form constantly under physiologic conditions, although their rate of formation is markedly increased in hyperglycemia and oxidizing conditions. Starting from the most relevant hypotheses on the pathogenesis of periodontal diseases, the present review outlines its relationship with oxidative stress and inflammation response in order to make a critical evaluation of the potential role of AGEs in periodontal deterioration. Although direct evidence for the presence of AGEs in the periodontal ligament is still lacking, valuable approaches based on the use of periodontal cells along with genetic and biochemical studies in animal models and chronic periodontal patients support a potential role for protein glycation in the aetiology and severity of this disease. Following a review of the current literature, the present study highlights the need for further investigation on the presence of AGEs in the periodontal ligament as a means for the comprehension of the pathogenic mechanisms underlying periodontal diseases in order to develop prevention and treatment modalities for this dysfunction.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Produtos Finais de Glicação Avançada/fisiologia , Doenças Periodontais/metabolismo , Animais , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Humanos , Doenças Periodontais/tratamento farmacológico , Doenças Periodontais/etiologia , Doenças Periodontais/patologia
7.
Transplant Proc ; 41(10): 4420-1, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20005413

RESUMO

Kidney transplantation is the treatment of choice for those affected by end-stage renal disease. Consent for organ donation continues to be one of the greatest challenges to transplanting more patients waiting for a life-saving transplant. In an attempt to increase the donor pool for patients on kidney transplant waiting lists, transplant surgeons and physicians have expanded their acceptance criteria to include expanded criteria donors, donation after cardiac death donors, as well as those donors who present unique technical challenges to organ recovery. Here we report a successful kidney transplant from a kidney donor who died from cardiac causes and who previously underwent an ileal conduit for a neurogenic urinary bladder secondary to a spinal cord injury.


Assuntos
Morte Súbita Cardíaca , Falência Renal Crônica/cirurgia , Transplante de Rim/fisiologia , Derivação Urinária , Adulto , Cadáver , Humanos , Masculino , Doadores de Tecidos , Coleta de Tecidos e Órgãos/métodos
8.
Am J Transplant ; 8(4): 897-904, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18324979

RESUMO

This case report focuses on the University of Wisconsin Hospital and Clinics Organ Procurement Organization (UWHC-OPO) efforts to produce a verifiable and demonstrable increase in organ donations by developing a replicable, transferable and feasible model intervention for increasing health care professionals' support for donation after cardiac death (DCD). A grant from the US Department of Health and Human Services funded a 3-year study allowing the UWHC-OPO to (i) identify barriers to and opportunities for increasing DCD support among those involved in the donation request process, (ii) implement this better understanding of these support factors in the creation of intervention materials designed to increase knowledge of and support for DCD and finally (iii) to track and document the progress made in increasing knowledge, support, number of hospitals with DCD protocols, actual requests made and number of DCD donors. The results of the model intervention were extremely positive, showing lasting increases in DCD knowledge and support, adoption of DCD protocols and referrals in the two tracking survey stages following the intervention. Perhaps most notably, DCD donor numbers within the UWHC-OPO region increased 93% in the year following the intervention and 179% to date.


Assuntos
Morte Súbita Cardíaca , Doadores de Tecidos , Cadáver , Documentação , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Relações Profissional-Paciente , Apoio Social , Coleta de Tecidos e Órgãos , Obtenção de Tecidos e Órgãos/organização & administração , Estados Unidos , Listas de Espera
9.
Transplant Proc ; 40(1): 219-23, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18261591

RESUMO

Morphologic characteristics of the graft have been proposed as a major contributor to the long-term outcomes in orthotopic liver transplantation (OLT). Our objective was to determine the impact of donor variables, including donor age, donor-recipient HLA match, and type of donation (DCD vs donation after brain death [DBD]), on the outcome of OLT in 192 patients with hepatitis C virus (HCV). Fourteen patients underwent OLT from donation after cardiac death (DCD) donors and 188 from DBD donors. Mean donor age, warm ischemia time at recovery, and cold ischemia time were similar between the groups. Overall graft survival rate at 1 year (55% DCD vs 85% DBD) and 5 years (46% DCD vs 78% DBD) was significantly lower in the DCD group (P = .0003). Similarly, patient survival rate at 1 year (62% DCD vs 93% DBD) and 5 years (62% DCD vs 82% DBD) was significantly lower in the DCD group (P = .0295). Incidences of hepatic artery thrombosis, portal vein thrombosis, and primary nonfunction were similar between the DCD and DBD groups. The incidence of liver abscess with ischemic-type biliary stricture was higher in recipients from DCD as compared with DBD (42% vs 2%). A trend toward lower graft survival was noted in recipients from donors older than 60 years of age in the HCV population (P = .07), with statistically lower patient survival (P = .02). Donor- recipient HLA matching did not appear to correlate with OLT outcome in patients with HCV. DCD donors and donors older than 60 years of age significantly impact patient and graft survival. Lower graft and patient survival in recipients from DCD donors does not appear to be related to early disease recurrence.


Assuntos
Hepatite C/cirurgia , Transplante de Fígado/fisiologia , Doadores de Tecidos/estatística & dados numéricos , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Cadáver , Feminino , Sobrevivência de Enxerto , Humanos , Testes de Função Hepática , Transplante de Fígado/mortalidade , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
10.
Am J Transplant ; 8(1): 193-200, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17973964

RESUMO

Findings are reported from a US Department of Health and Human Services (DHHS) funded study to identify barriers to increasing support for donations after cardiac death by health professionals. A donations after cardiac death (DCD) acceptance model is conceptualized and tested via 806 survey responses from certified requestors, all of whom had their identities protected through Institutional Review Board (IRB) protocol. The overall model was significant and explained 35% of the variation in DCD support. Greater knowledge about DCD, greater trust in the organ procurement organization (OPO) and a belief that futility has been reached were all positively associated with DCD acceptance. Negative perceptions of DCD versus brain death, transitioning from caregiving to donation advocate, concerns about the DCD process and the idea that DCD leads to active participation in the death reduced its support. The three greatest impediments to support of DCD exist when health professionals feel they are playing an active role in killing the patient, that a state of death has not yet been reached, and that DCD has more psychological barriers than does the brain death donation process. Opportunities and strategic initiatives are discussed to overcome these barriers, including the value of communication and education initiatives and the need for well-trained requestors. The implementation of these strategic guidelines helped to increase the number of DCD donors by 225%.


Assuntos
Atitude Frente a Saúde , Morte , Relações Profissional-Família , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Feminino , Humanos , Estudos Longitudinais , Masculino , Modelos Psicológicos , Doadores de Tecidos/psicologia , Coleta de Tecidos e Órgãos/psicologia
11.
Pediatr Transplant ; 11(6): 661-70, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17663691

RESUMO

Developments in surgical technique, immunosuppression, organ procurement and preservation, and patient selection criteria have resulted in improved long-term patient and graft survival after pediatric liver transplantation. In this study, we examined the results of 196 liver transplants performed in 155 pediatric patients at University of Wisconsin Children's Hospital. Patients were divided into two groups according to age at the time of liver transplant. Infants under 12 months of age comprised Group 1 (n=74) and children from one to 18 yr comprised Group 2 (n=122). Outcomes for whole, reduced-size, and split liver transplantation were compared in infants and children. Biliary atresia was the most common indication in both groups. Patients underwent 128 whole size, 50 reduced size, and 18 split liver transplants. Forty-one retransplantations were performed in 14 infants (18.9%) and in 27 children (22.1%). One hundred eleven patients (56.6%) had one or more rejection episode [37 infants (50.0%) and 74 children (60.6%)]. Thirty-nine patients (19.8%) developed CMV infections, 42 (21.4%) developed EBV infections, and 14 developed PTLD (six infants and eight children). Thirty-six patients (18.3%) developed HAT. Seven patients (4.5%) developed malignancy (one infant and six children). Out of 155 patients, 33 (21.3%) died during the study period. The most common etiology of mortality included central nervous system pathology (n=7; 4.5%), sepsis (n=6; 3.8%), and cardiac causes (n=6; 3.8%). One-, five-, and 10-yr actuarial patient survival was 86, 79, and 74% in infants and 90, 83 and 80% in children. Graft survival at one, five, and 10 yr was 77, 73 and 71% in infants and 88, 81 and 78% in children, respectively. Despite its technical challenges, the outcomes of liver transplantation in pediatric patients with end-stage liver disease are excellent and result in significant long-term patient and graft survival.


Assuntos
Transplante de Fígado , Adolescente , Fatores Etários , Criança , Pré-Escolar , Seguimentos , Sobrevivência de Enxerto , Hospitais Universitários , Humanos , Lactente , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Wisconsin
13.
Am J Transplant ; 6(2): 281-91, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16426312

RESUMO

A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.


Assuntos
Morte Súbita Cardíaca , Obtenção de Tecidos e Órgãos/ética , Adolescente , Adulto , Criança , Humanos , Transplante de Fígado/mortalidade , Transplante de Fígado/estatística & dados numéricos , Pessoa de Meia-Idade , Seleção de Pacientes
14.
Exp Mol Med ; 37(5): 476-81, 2005 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-16264272

RESUMO

The administration of mineral sulphur water is an alternative experimental approach for the treatment of rheumatic diseases, such as osteoarthritis (OA), that cause the degeneration of bone and cartilage and sufferance to the patients. Chondroitin sulfate (CS) is a symptomatic slow acting nutropeucital agent currently used in molecular therapy of OA. Therefore, we have studied the role and efficacy of the selective soil paste from the mineral sulphur enriched spring (mud)-therapy alone or in combination with CS in the treatment of OA. The study was performed on 40 C57 Black 6N mice, an experimental model which spontaneously develop an osteoarthritic process. The animals were divided in 4 groups and were treated with the single agents or with the combination. After 30 days of treatment all the mice were sacrificed and right knees and blood were collected. It was found that CS determined a reduction of radiological and histological features of chondrodegeneration and that mud-therapy increased the effects of CS in the animal group treated with the combination. However, the effects of thermal therapy alone were not statistically significant. Since OA is characterized by an increase of the production of nitric oxide (NO) by chondrocytes in extracellular matrix with its consequent elevation in serum and synovial fluid, we have evaluated the effects of the treatments on serum NO levels. CS alone induced a statistically significant reduction of NO serum levels (90+/-13 micromM vs 219+/-60 microM of control group, P<0.05) while mud-therapy alone induced a not statistically significant reduction of serum NO (170+/-62 microM, P>0.05). However, the latter strongly potentiated the decrease of serum NO induced by CS (31+/-1.5 microM) with a high statistical significance if compared to both the control group (P<0.01) and the CS-treated group (P<0.05). In conclusion, this study demonstrates that mud-therapy with sulphur mineral water could represent an important phase of the therapeutic strategy of OA. This experimental strategy could integrate and potentiate the standard pharmacological tools. Moreover, we have set a valid experimental in vivo model for the study of the thermal effects on the development of OA.


Assuntos
Condrócitos/efeitos dos fármacos , Sulfatos de Condroitina/farmacologia , Terapias Complementares/métodos , Citoproteção/efeitos dos fármacos , Águas Minerais/uso terapêutico , Enxofre/farmacologia , Animais , Apoptose/efeitos dos fármacos , Sulfatos de Condroitina/efeitos adversos , Feminino , Masculino , Camundongos , Óxidos de Nitrogênio/sangue , Enxofre/uso terapêutico
15.
Biochem Pharmacol ; 70(4): 560-9, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15982641

RESUMO

This study deals with the combination of chloroquine (CQ, an anti-malaric drug) and 3'-azido-3'-deoxythymidine (AZT, anti-human immuno-deficiency virus (HIV) drug) with a chimeric toxin (TS) obtained by chemical linking of saporin (a ribosome inactivating protein from the plant Saponaria officinalis) and human transferrin, in the intoxication of the human chronic myeloid leukaemia cells (K562). Our data demonstrate that AZT, at concentrations comparable to those reached in the blood of HIV-infected patients under pharmacological treatment with this drug, can increase the toxicity of TS in cooperation with CQ inducing an increased effect on protein synthesis in K562 cells ( approximately 50% inhibition of protein synthesis for TS alone, and TS with AZT and approximately 70% with both AZT and CQ). Furthermore, pre-treatment of cells with AZT alone can induce an increase of apoptosis in K562 cells intoxicated with TS. By comparing data obtained with the model toxin ricin, we get indications that the two toxins partially differ in their intracellular routes, also suggesting that chimeric constructs containing ricin-like toxins (i.e. immunotoxins) could be coupled with the use of common and cheap drugs for the treatment of cancer in HIV-infected patients.


Assuntos
Cloroquina/farmacologia , Imunotoxinas/química , N-Glicosil Hidrolases/química , Proteínas de Plantas/química , Proteínas Recombinantes de Fusão/toxicidade , Transferrina/química , Zidovudina/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Microscopia Confocal , Proteínas Recombinantes de Fusão/química , Proteínas Inativadoras de Ribossomos Tipo 1 , Saporinas
16.
J Cell Physiol ; 201(1): 71-83, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15281090

RESUMO

We have previously reported that interferon-alpha (IFNalpha) induces apoptosis and EGF can antagonize this effect in human epidermoid cancer KB cells. Since apoptosis occurs together with cytoskeleton reorganization we have evaluated if IFNalpha and EGF could modulate cell remodeling in our experimental conditions. We have found that 48 h 1,000 IU/ml IFNalpha induced structural reorganization of stress fibers and membrane delocalization and partial capping of the actin severing protein gelsolin. The transfection of KB cells with both a wild type (WT) or a C-terminal truncated form of gelsolin caused overexpression of the protein and an increase of both the spontaneous and IFNalpha-induced apoptosis and cell cytoskeletal modifications. In fact, after 48 h of treatment IFNalpha induced 45% of apoptotic cell death in parental cells while an approximately 80% of cell population was apoptotic in transfected cells. These effects occurred together with an increase of the expression and consequent degradation of gelsolin. Again the addition of EGF to IFNalpha-treated transfected cells caused a recovery of the apoptosis. Notably, IFNalpha and EGF did not modify the expression of other molecules associated to cytoskeleton such as focal adhesion kinase and vinculin. In the same experimental conditions IFNalpha induced also gelsolin cleavage that occurred together with caspase-3 activation and release of cytochrome c. All these effects were antagonized by the exposure of IFNalpha-treated KB to 10 nM EGF for the last 12 h. Moreover, the specific inhibition of caspase-3 with 20 microM DEVD completely abrogated apoptosis and gelsolin cleavage induced by IFNalpha. In conclusion, our data are the first demonstration that IFNalpha can induce morphological cell changes that are peculiar of apoptosis onset through the caspase-3-mediated cleavage of gelsolin. Furthermore, we have demonstrated that EGF is able to antagonize these effects through the inhibition of caspase-3 activation.


Assuntos
Antineoplásicos/farmacologia , Apoptose/fisiologia , Carcinoma de Células Escamosas , Fator de Crescimento Epidérmico/farmacologia , Gelsolina/metabolismo , Interferon-alfa/farmacologia , Neoplasias Orofaríngeas , Apoptose/efeitos dos fármacos , Caspase 3 , Caspases/metabolismo , Linhagem Celular Tumoral/citologia , Linhagem Celular Tumoral/efeitos dos fármacos , Citocromos c/metabolismo , Gelsolina/genética , Expressão Gênica , Humanos
17.
J Biochem ; 133(6): 757-65, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12869532

RESUMO

Interferon-alpha (IFNalpha) can induce apoptosis, a process regulated by a complex network of cell factors. Among these, eukaryotic initiation factor-5A (eIF-5A) is peculiar because its activity is modulated by the post-translational formation of the amino acid hypusine. Here we report the effects of IFNalpha and epidermal growth factor (EGF) on apoptosis and eIF-5A activity in human epidermoid oropharyngeal KB and lung H1355 cancer cells. We found that 48-h exposure to 1000 and 2000 IU/ml IFNalpha induced about 50% growth inhibition and apoptosis in H1355 and KB cells, respectively, and the addition of EGF completely antagonized this effect. When IFNalpha induced apoptosis, a hyperactivation of MEK-1 and ERK signalling and a decrease of the hypusine-containing form and, thus, of eIF-5A activity were recorded. The latter effect was again antagonized by the addition of EGF to IFNalpha-pretreated cells, probably through the activation of the EGF-->ERK-dependent pathway, since the addition of the specific MEK-1 inhibitor PD098059 abrogated the recovery of intracellular hypusine content induced by EGF in IFNalpha-pretreated cancer cells. Subsequently, we evaluated if the hypusine synthesis inhibitor (and eIF-5A inactivator) N1-guanyl-1,7-diaminoheptane (GC7) synergized with IFNalpha in the induction of cell growth inhibition and apoptosis. The analysis of the isobologram of IFNalpha and GC7 demonstrated a strong synergism between the two drugs in inducing cell growth inhibition. We also found that GC7 and IFNalpha had a synergistic effect on apoptosis. These data suggest that the apoptosis induced by IFNalpha could be regulated by eIF-5A that, therefore, could represent a useful target for the potentiation of IFNalpha antitumor activity.


Assuntos
Antineoplásicos/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Guanina/análogos & derivados , Interferon-alfa/farmacologia , Lisina/análogos & derivados , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas de Ligação a RNA , Apoptose , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Guanina/farmacologia , Humanos , Células KB , Lisina/biossíntese , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fatores de Iniciação de Peptídeos/antagonistas & inibidores , Fosforilação , Processamento de Proteína Pós-Traducional , Fator de Iniciação de Tradução Eucariótico 5A
18.
Thyroid ; 12(9): 815-21, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12481948

RESUMO

We present a prospective study on the long-term efficacy of percutaneous ethanol injection (PEI) treatment of a large series of symptomatic thyroid cystic nodules (STCN). Ninety-eight patients (72 females and 26 males) were treated. The mean basal volume of the STCN was 35.3 mL. In 92 of 98 patients PEI treatment induced a greater than 50% nodule shrinkage, only 6 of 92 responder patients relapsed at a follow-up of 9 years. Moreover, all the patients had a significant clinical benefit because a significant reduction of the cyst-associated symptoms was recorded. Furthermore, a limited number of sessions was required for the treatment of cysts larger than 40 mL (mean +/- standard deviation [SD]: 2.7 +/- 0.75) demonstrating the feasibility of the procedure also in the treatment of large cysts. In conclusion, PEI is an effective and inexpensive procedure with a high patient compliance and long-lasting effects in the treatment of cysts larger than 40 mL.


Assuntos
Etanol/administração & dosagem , Solventes/administração & dosagem , Nódulo da Glândula Tireoide/tratamento farmacológico , Administração Cutânea , Adolescente , Adulto , Idoso , Cistos/diagnóstico por imagem , Cistos/tratamento farmacológico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Resultado do Tratamento , Ultrassonografia
19.
Amino Acids ; 20(2): 91-104, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11332455

RESUMO

In the past years, the attention of scientists has mainly focused on the study of the genetic information and alterations that regulate eukaryotic cell proliferation and that lead to neoplastic transformation. An increasing series of data are emerging about the involvement of the initiation phase of translational processes in the control of cell proliferation. In this paper we review the novel insights on the biochemical and molecular events leading to the initiation and its involvement in cell proliferation and tumourigenesis. We describe the structure, regulation and proposed functions of the eukaryotic initiation factor 5A (eIF-5A) focusing the attention on its involvement in the regulation of apoptosis and cell proliferation. Moreover, we describe the modulation of its activity (through the reduction of hypusine synthesis) in apoptosis induced either by tissue transglutaminase or interferon a. Finally, we propose eIF-5A as an additional target of anti-cancer strategies.


Assuntos
Antineoplásicos/farmacologia , Apoptose/fisiologia , Lisina/metabolismo , Fatores de Iniciação de Peptídeos/fisiologia , Proteínas de Ligação a RNA , Transporte Ativo do Núcleo Celular , Animais , Antineoplásicos/química , Divisão Celular/fisiologia , Desenho de Fármacos , Humanos , Lisina/análogos & derivados , Fatores de Iniciação de Peptídeos/efeitos dos fármacos , Biossíntese de Proteínas , Processamento de Proteína Pós-Traducional , RNA Mensageiro/metabolismo , Fator de Iniciação de Tradução Eucariótico 5A
20.
J Gastrointest Surg ; 5(6): 594-601; discussion 601-2, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12086897

RESUMO

The use of orthotopic liver transplantation (OLTX) for the treatment of hepatocellular carcinoma (HCC) has generally become restricted to carefully selected cases of small oligocentric tumors. However, it is not uncommon to find previously undetected HCC within recipient cirrhotic livers at the time of hepatectomy. The impact of unsuspected HCC on patient outcomes remains unclear. A retrospective analysis of our institutional experience with adult primary OLTX was performed comparing recipients with incidental HCC (group 1), recipients with known or suspected HCC (group 2), and recipients confirmed by pathologic examination to be tumor free (group 3). Between 1984 and 2000, 27 patients in group 1, 12 patients in group 2, and 612 patients in group 3 underwent primary OLTX. Tumors were smaller (P = 0.0172) in group 1 than in group 2; however, the number of tumors and the histologic findings were similar in the groups. Incidence of bilobar involvement, vascular invasion, portal vein tumor thrombus, lymphatic involvement, and distant metastasis at the time of OLTX did not differ significantly between these groups. Four-year patient survival appeared to be lower in group 1 (70.0%) than in group 3 (79.0%) (P = 0.0546); 4-year patient survival was significantly worse in group 2 (31.0%) compared to group 3 (P = 0.0106). Thus, in our experience, incidentally diagnosed cases of HCC possess many of the same features of malignancy as preoperatively diagnosed HCC. Indeed, patient survival after OLTX appears to be adversely affected by the presence of incidental HCC.


Assuntos
Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Cirrose Hepática/mortalidade , Cirrose Hepática/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Transplante de Fígado/métodos , Adulto , Biópsia por Agulha , Carcinoma Hepatocelular/cirurgia , Comorbidade , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Probabilidade , Prognóstico , Modelos de Riscos Proporcionais , Sistema de Registros , Estudos Retrospectivos , Análise de Sobrevida , Transplante Homólogo , Resultado do Tratamento
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