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Cateterismo Periférico , Remoção de Dispositivo/métodos , Procedimentos Endovasculares , Artéria Femoral , Hemorragia/prevenção & controle , Técnicas Hemostáticas/instrumentação , Dispositivos de Oclusão Vascular , Cateterismo Periférico/efeitos adversos , Artéria Femoral/diagnóstico por imagem , Hemorragia/etiologia , Humanos , Masculino , Punções , Resultado do Tratamento , Adulto JovemRESUMO
PURPOSE: To investigate the midterm safety and efficacy of computed tomography (CT)-guided percutaneous gallbladder cryoablation in swine. MATERIALS AND METHODS: Three swine underwent gallbladder cryoablation. Cryoprobes were positioned percutaneously at the gallbladder margins or within the gallbladder lumen under CT guidance. Two freeze/thaw cycles were performed. One animal was euthanized on postprocedure day 4 as a result of hematemesis unrelated to the ablation. The other 2 animals were euthanized at postprocedure days 30 and 48, respectively. The gallbladder and bile ducts were resected and examined microscopically. RESULTS: Gallbladder cryoablation was completed with freeze/thaw cycle durations of 7.5-10 minutes (mean, 9.4 min ± 1.3) and ablation margins of 5.8-11.5 mm (mean, 7.8 mm ± 1.9). No nontarget ablation was observed. Laboratory values at postprocedure day 4 and the time of euthanasia were within normal limits. Two of 3 animals thrived and exhibited appropriate activity and weight gain. Contrast-enhanced CT immediately before euthanasia demonstrated delayed linear enhancement of the gallbladder wall. Gross inspection at autopsy revealed fibrotic-appearing gallbladders. Cholecystography revealed no communication to the biliary tree. Histologic examination demonstrated complete gallbladder wall fibrosis. Autopsy of the animal euthanized on day 4 revealed a gastric mucosal ulcer distant from the ablation site with no gastric serosal injury. CONCLUSIONS: Gallbladder cryoablation is a promising alternative to surgical cholecystectomy, with complete transmural gallbladder wall fibrosis and cystic duct occlusion seen at 30 and 48 days in swine. Further studies are required to establish procedural safety and long-term efficacy.
Assuntos
Criocirurgia/métodos , Vesícula Biliar/cirurgia , Radiografia Intervencionista , Tomografia Computadorizada por Raios X , Animais , Modelos Animais , Projetos Piloto , SuínosRESUMO
PURPOSE: To investigate the feasibility of percutaneous gallbladder cryoablation (GBC) under CT guidance in a swine model with histopathologic correlation. MATERIALS AND METHODS: Institutional Animal Care and Use Committee approval was obtained for this study protocol. Five pigs underwent GBC. Under CT guidance, 3-4 cryoprobes were positioned percutaneously at the gallbladder margins. Thermocouple probes were placed percutaneously at the gallbladder fundus, neck, free wall, and gallbladder fossa. Two freeze-thaw cycles ranging from 10 to 26 min were performed. The subjects were sacrificed 5 h after cryoablation. The gallbladder and bile ducts were resected, stained, and examined microscopically. RESULTS: GBC was completed in all subjects. A 10-mm ablation margin was achieved beyond all gallbladder walls. Thermocouple probes reached at least -20 °C. Intra-procedural body temperature decreased to a minimum of 35 °C but recovered after the procedure. Intra- and post-procedural vital signs otherwise remained within physiologic parameters. Non-target ablation occurred in the stomach and colon of the first two subjects. Histology demonstrated complete denudation of the gallbladder epithelium, hemorrhage, and edema within the muscularis layer, and preservation of the microscopic architecture of the common bile duct in all cases. CONCLUSION: Percutaneous gallbladder cryoablation is feasible, with adequate ablation margins obtained and histologic changes demonstrating transmural necrosis. Adjacent structures included in the ablation may require conservative ablation zones, hydrodissection, or continuous saline lavage.
Assuntos
Colecistectomia , Criocirurgia/métodos , Vesícula Biliar/cirurgia , Animais , Estudos de Viabilidade , Modelos Animais , Radiografia Intervencionista , Suínos , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: Since their discovery by Roentgen in 1895, x-rays have contributed to some of the most important advances in science. X-ray crystallography is an imaging technique that uses x-ray diffraction to evaluate the molecular structure of a crystalline solid. This article discusses the critical role played by x-ray crystallography in the elucidation of the structure of DNA. CONCLUSION: The story of DNA includes insights on molecular structure provided by x-rays and also lessons on scientific collaboration and innovation that can be applied to radiology today.
Assuntos
Cristalografia por Raios X/história , DNA/química , História do Século XIX , História do Século XX , HumanosRESUMO
BACKGROUND: Experience with non-antigenic galactose alpha1,3 galactose (alphaGal) polymers and development of alphaGal deficient pigs has reduced or eliminated the significance of this antigen in xenograft rejection. Despite these advances, delayed xenograft rejection (DXR) continues to occur most likely due to antibody responses to non-Gal endothelial cell (EC) antigens. METHODS: To gauge the diversity of the non-Gal antibody response we used antibody derived from CD46 transgenic heterotopic cardiac xenografts performed without T-cell immunosuppression, Group A (n = 4) and Gal knockout (GT-KO) heart transplants under tacrolimus and sirolimus immunosuppression, Group B (n = 8). Non-Gal antibody was measured by flow cytometry and by western blots using GT-KO EC membrane antigens. A nanoLC/MS/MS analysis of proteins recovered from 2D gels was used to identify target antigens. RESULTS: Group A recipients exhibited a mixed cellular and humoral rejection. Group B recipients mainly exhibited classical DXR. Western blot analysis showed a non-Gal antibody response induced by GT+ and GT-KO hearts to an overlapping set of pig aortic EC membrane antigens. Proteomic analysis identified 14 potential target antigens but failed to define several immunodominant targets. CONCLUSIONS: These experiments indicate that the non-Gal antibody response is directed to a number of stress response and inflammation related pig EC antigens and a few undefined targets. Further analysis of these antibody specificities using alternative methods is required to more fully define the repertoire of non-Gal antibody responses.
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Anticorpos Heterófilos/biossíntese , Transplante de Coração/efeitos adversos , Transplante de Coração/imunologia , Animais , Animais Geneticamente Modificados , Especificidade de Anticorpos , Dissacarídeos/deficiência , Dissacarídeos/genética , Dissacarídeos/imunologia , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Transplante de Coração/patologia , Humanos , Papio anubis , Proteômica , Suínos , Transplante HeterólogoRESUMO
By cross-linking B7-DC on dendritic cells (DC) the human IgM antibody (B7-DC XAb) shifts polarized immune responses from Th2 to Th1 in an antigen-specific manner. The molecular determinants governing the ability of DC to reprogram the polarity of T cell recall responses are not yet known. In addition to the expected role of T-bet expressed by T cells in regulating Th1 responses, we find using in vitro assays and an established in vivo model of allergic airway inflammation that T-bet expression by DC is also required for the polarity shift promoted by B7-DC XAb. T-bet expression by both T cells and DC is critically important for B7-DC XAb-induced down-regulation of IL-4, up-regulation of IFN-gamma and suppression of allergic airway inflammation. Moreover, retroviral reconstitution of T-bet expression in T-bet-deficient DC rescued their ability to modulate both naive and memory T-cell responses from Th2 to Th1. Our observations further our understanding of the critical mediators controlling the ability of DC to modify the responses of previously activated T cells and reveal the interesting use of the same transcription factor to regulate the inductive phenotype of DC and the inducible phenotype of T cells.
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Células Dendríticas/imunologia , Pulmão/imunologia , Hipersensibilidade Respiratória/imunologia , Proteínas com Domínio T/metabolismo , Células Th1/imunologia , Células Th2/imunologia , Transferência Adotiva , Animais , Antígeno B7-1/imunologia , Antígeno B7-1/metabolismo , Polaridade Celular , Células Cultivadas , Técnicas de Cocultura , Células Dendríticas/metabolismo , Regulação para Baixo , Inflamação/imunologia , Inflamação/metabolismo , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-4/imunologia , Interleucina-4/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovalbumina/imunologia , Proteína 2 Ligante de Morte Celular Programada 1 , Hipersensibilidade Respiratória/metabolismo , Células Th1/metabolismo , Células Th2/metabolismo , Regulação para CimaRESUMO
UNLABELLED: Xenotransplantation using porcine organs may resolve a chronic shortage of donor organs for clinical transplantation if significant immunological barriers can be overcome. To determine the potential role of T lymphocytes in Xenograft (Xg) rejection, we transplanted transgenic hCD46 porcine hearts heterotopically into baboon recipients. METHODS: Recipients were treated to deplete anti-Gal antibody with a non-antigenic alpha-Gal polyethylene glycol polymer (TPC) (n = 2), TPC plus rituximab (anti-CD20) (n = 1) or were untreated (n = 1). None of the recipients received T-cell immunosuppression. RESULTS: All Xgs failed within 7 days and showed evidence of a mixed humoral and cellular rejection process. Cellular infiltration consisting primarily of CD4+ T cells and few CD8+ T cells. Proliferation and cytotoxicity assays showed sensitization of CD4+ and CD8+ T cells that reacted with porcine IFN-gamma (pIFN-gamma)-stimulated porcine aortic endothelial cells (PAEC). The CD4+ lymphocytes displayed greater cytotoxicity than CD8+ cells. An increased frequency of PAEC-specific interleukin (IL) 2 and IFN-gamma-secreting T cells was observed, suggesting a Th1 cytokine bias. An increase in the percentage of circulating CD4+CD28- cells was observed at the time of rejection and over 50% of the CD4+ cells recovered from residual pig tissue at necropsy lacked CD28 expression. CONCLUSIONS: These findings show that lymphocytes are efficiently stimulated by PAEC antigens and can mediate direct tissue destruction. These studies (1) provide an insight into the potential of cellular-mediated cardiac Xg rejection, (2) show for the first time the induction of cytotoxic pig-specific CD4+CD28- lymphocytes and (3) provide a rational basis for determining different modes of immunosuppression to treat Xg rejection.