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1.
Allergy ; 71(1): 90-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26416225

RESUMO

BACKGROUND: Although there is evidence that exposure to tobacco smoke is harmful to children's respiratory health, the effects of tobacco smoke exposure on the regulation of immunoglobulin E (IgE)-mediated immune responses to specific allergens remain unclear. This study aimed to investigate the relationship between objectively assessed tobacco smoke exposure and specific IgE profiles for a broad spectrum of allergens in a population setting. METHODS: Children aged 5-18 years (N = 1315) were assessed using serum cotinine measurement and microarray-based multiplexed detection of specific IgE against 40 allergens. RESULTS: Serum cotinine levels were positively associated with sensitization to foods (adjusted odds ratio [AOR] = 4.95; 95% CI: 1.59-15.34), cockroaches (AOR = 3.77; 95% CI: 1.49-9.51), and pollen (AOR = 2.84; 95% CI: 1.20-6.73) while the association was borderline significant for animals (AOR = 2.53; 95% CI: 0.92-6.93). No associations were found for sensitization against mites, mold, and latex. When considering the degree of allergic sensitization, serum cotinine levels were positively correlated to the number of sensitization to cockroaches (P = 0.004), pollen (P = 0.006), and foods (P < 0.001), with statistically significant positive dose-response relationships (all P < 0.01). Similar results were observed when summing up specific IgE concentrations for the aforementioned allergen categories. CONCLUSIONS: The association between tobacco smoke exposure and IgE sensitization to environmental allergens varies for different allergens among children. This study demonstrates that elevated serum cotinine levels are significantly associated with IgE sensitization to cockroaches, grass pollen, and certain foods, with potential dose-dependent relationships.


Assuntos
Exposição Ambiental/efeitos adversos , Hipersensibilidade/epidemiologia , Hipersensibilidade/etiologia , Imunoglobulina E/imunologia , Nicotiana/efeitos adversos , Fumaça/efeitos adversos , Adolescente , Alérgenos/imunologia , Animais , Criança , Pré-Escolar , Cotinina/sangue , Feminino , Humanos , Imunização , Imunoglobulina E/sangue , Masculino , Razão de Chances , Vigilância da População , Fatores de Risco
2.
J Thromb Haemost ; 9(3): 593-602, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21143376

RESUMO

BACKGROUND AND OBJECTIVES: Septic shock is a major cause of morbidity and mortality in intensive care units, but there is still no effective therapy for the patients. We evaluated the effects of rhodostomin (Rn), an Arg-Gly-Asp-containing snake venom disintegrin, on lipopolysaccharide (LPS)-activated phagocytes in vitro and LPS-induced endotoxemia in vivo. METHODS AND RESULTS: Rn inhibited adhesion, migration, cytokine production and mitogen-activated protein kinase (MAPK) activation of macrophage induced by LPS. Flow cytometric analysis revealed that Rn specifically blocked anti-αv mAb binding to RAW264.7. Besides inhibiting MAPK activation of THP-1, Rn bound to LPS-activated THP-1 and specifically blocked anti-αvß3 mAb binding to THP-1. Binding assays proved that integrin αvß3 was the binding site for rhodostomin on phagocytes. Rn reversed the enhancement of fibronectin and vitronectin on LPS-induced monocyte adhesion and cytokine release. Transfection of integrin αv siRNA also inhibited LPS-induced activation of monocyte, and Rn exerted no further inhibitory effect. Furthermore, Rn significantly decreased the production of tumor necrosis factor-α (TNF-a), interleukin (IL)-6, -1ß and -10 and attenuated cardiovascular dysfunction, including blood pressure and heart pulse, and thrombocytopenia in LPS-induced endotoxemic mice. Rn also protected against tissue inflammation as evidenced by histological examination. CONCLUSIONS: Rn may interact with αvß3 integrin of monocytes/macrophages leading to interfere with the activation of phagocytes triggered by LPS. These results suggest that the protective function of Rn in LPS-induced endotoxemia may be attributed to its anti-inflammation activities in vivo.


Assuntos
Endotoxemia/tratamento farmacológico , Endotoxemia/fisiopatologia , Integrina alfaVbeta3/fisiologia , Peptídeos/farmacologia , Animais , Sítios de Ligação , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Citocinas/biossíntese , Desintegrinas/farmacologia , Humanos , Integrina alfaVbeta3/antagonistas & inibidores , Integrina alfaVbeta3/genética , Lipopolissacarídeos/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fagócitos/efeitos dos fármacos , Fagócitos/fisiologia , Interferência de RNA , RNA Interferente Pequeno/genética , Trombocitopenia/sangue , Trombocitopenia/tratamento farmacológico
3.
Transplant Proc ; 42(6): 2138-41, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20692427

RESUMO

To mitigate hyperacute rejection, pigs have been generated with alpha-Gal transferase gene knockout and transgenic expression of human decay accelerating factor (hDAF), MCP, and CD59. Additionally, heme-oxygenase-1 (HO-1) has been suggested to defend endothelial cells. Sera (MS) (0%, 1%, 5%, 10%, and 15%) from Formosan macaques (Macaca cyclopis, MC), an Old World monkey wildly populated in Taiwan, was used to test the protective in vitro, effects of hDAF or hDAF/hHO-1 on porcine aortic endothelial cells (pAEC) derived from hDAF(+), hDAF(+)/hHO-1(+), and hDAF(+)/hHO-1(-) and 1 nontransgenic pAEC. Ten percent human serum (HS) served as a positive control. When MS addition increased to 10% or 15%, all transgenic pAEC exhibited a greater survival than nontransgenic pAEC. Noticeably, 15% MS reduced survived to <10% versus >40% in nontransgenic and transgenic pAEC, respectively. These results revealed that hDAF exerted protective effects against MC complement activation. However, comparing with 10% MS and HS in pAEC of nontransgenic pigs, the survivability was higher in HS, suggesting that complement activation by MS was more toxic than that by HS. Furthermore, hDAF(+)/hHO-1(+) showed no further protection against effects of MS on transgenic pAEC.


Assuntos
Antígenos CD55/genética , Heme Oxigenase-1/genética , Animais , Animais Geneticamente Modificados , Antígenos CD59/genética , Técnicas de Inativação de Genes , Rejeição de Enxerto/prevenção & controle , Humanos , Rim/fisiologia , Macaca/genética , Macaca/imunologia , Macaca/metabolismo , Papio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Transgenes , Transplante Heterólogo
4.
Am J Transplant ; 8(12): 2516-26, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19032222

RESUMO

The use of alpha1,3-galactosyltransferase gene-knockout (GalT-KO) swine donors in discordant xenotransplantation has extended the survival of cardiac xenografts in baboons following transplantation. Eight baboons received heterotopic cardiac xenografts from GalT-KO swine and were treated with a chronic immunosuppressive regimen. The pathologic features of acute humoral xenograft rejection (AHXR), acute cellular xenograft rejection (ACXR) and chronic rejection were assessed in the grafts. No hyperacute rejection developed and one graft survived up to 6 months after transplantation. However, all GalT-KO heart grafts underwent graft failure with AHXR, ACXR and/or chronic rejection. AHXR was characterized by interstitial hemorrhage and multiple thrombi in vessels of various sizes. ACXR was characterized by TUNEL(+) graft cell injury with the infiltration of T cells (including CD3 and TIA-1(+) cytotoxic T cells), CD4(+) cells, CD8(+) cells, macrophages and a small number of B and NK cells. Chronic xenograft vasculopathy, a manifestation of chronic rejection, was characterized by arterial intimal thickening with TUNEL(+) dead cells, antibody and complement deposition, and/or cytotoxic T-cell infiltration. In conclusion, despite the absence of the Gal epitope, acute and chronic antibody and cell-mediated rejection developed in grafts, maintained by chronic immunosupression, presumably due to de novo responses to non-Gal antigens.


Assuntos
Galactosiltransferases/genética , Galactosiltransferases/fisiologia , Rejeição de Enxerto/imunologia , Transplante de Coração/imunologia , Papio hamadryas/imunologia , Porco Miniatura/imunologia , Transplante Heterólogo/imunologia , Animais , Animais Geneticamente Modificados , Formação de Anticorpos/fisiologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Rejeição de Enxerto/patologia , Rejeição de Enxerto/fisiopatologia , Transplante de Coração/patologia , Transplante de Coração/fisiologia , Imunidade Celular/fisiologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Células Matadoras Naturais/patologia , Suínos , Porco Miniatura/genética , Trombose/patologia , Transplante Heterólogo/patologia , Transplante Heterólogo/fisiologia , Troponina T/sangue
6.
Transplant Proc ; 40(2): 570-3, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18374131

RESUMO

In allotransplantation, donor-recipient human leukocyte antigen (HLA) matches improve graft survival. For studies of the role of donor-recipient HLA II matching on xenotransplantation, we successfully generated HLA-DR15+ transgenic pigs the the skins of which were transplanted to SCID mice, which were thereafter reconstituted with HLA-DR15+ or -DR15(-) hPBMC. Cyclosporine was given intraperitoneally to SCID mice for 12 days. Human T cells were observed in SCID mice after reconstitution. Mixed lymphocytes responses showed greater responses by HLA-DR15(-) human peripheral blood mononuclear cells (hPBMC) against HLA-DR15+ porcine PBMC. HLA-DR15+ porcine skins survived more than 100 days in all SCID mice. HLA-DR15+ porcine skins were rejected in all non-SCID (Balb/c) mice. The histologic pictures of transplanted HLA-DR15+ porcine skins showed surviving porcine epithelium in remodeling murine dermis and little lymphocyte infiltration into the murine dermis. The long-term survival of HLA-DR15+ pig skin in all hPBMC-SCID mice might be due to poor engraftment or function of reconstituted T cells. Further studies are needed to clarify the role of donor-recipient matching of HLA-DR15.


Assuntos
Sobrevivência de Enxerto/imunologia , Antígenos HLA-DR/imunologia , Leucócitos Mononucleares/imunologia , Transplante de Pele/imunologia , Pele/imunologia , Animais , Subtipos Sorológicos de HLA-DR , Humanos , Terapia de Imunossupressão , Camundongos , Camundongos SCID , Suínos
7.
Transplant Proc ; 40(2): 578-80, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18374133

RESUMO

The shortage of human organs has encouraged scientists to develop genetically modified pigs for xenotransplantation, such as CD55 or CD46, and CD59 transgenesis as well as alpha-galactosyl transferase gene knockouts. In allotransplantation, the match of human leukocyte antigen class II (HLA-II) may improve graft survival although the role of HLA-II in xenotransplantation is unknown. HLA-II transgenic pigs, including DP, DQ, and DR, have been successfully generated and HLA-DR15+ transgenic pig skin pieces grafted onto severe congenital immunodeficiency (SCID) mice reconstituted intraperitoneally with HLA-DR15+ or HLA-DR15(-) human peripheral blood mononuclear cells (hPBMCs). This study sought to develop an animal model to evaluate the effects of HLA-DR matching on xenograft survival. Human CD4+ and CD8+ were detected from days 7 to 29 after hPBMC reconstitution in SCID mice. Both CD4+ and CD8+ cells of HLA-DR15(-) reconstituted SCID mice were significantly higher at day 29 postgrafting compared with HLA-DR15+ reconstituted SCID mice. An HLA-DR15+ transgenic pig dermal graft survived and integrated into SCID mice reconstituted with hPBMCs/HLA-DR15+ as proven by the histopathological finding that the collagen layer remained intact with little lymphocytic response. In contrast, the transgenic pig dermal graft showed more collagen disruption as well as mild to moderate lymphocytic infiltration when reconstituted in an hPBMC/HLA-DR15(-) SCID mouse. The results suggested that HLA-DR matching eased xenograft rejection; however, it was not yet clear that the response was mediated by T cells.


Assuntos
Animais Geneticamente Modificados , Sobrevivência de Enxerto/imunologia , Antígenos HLA-DR/imunologia , Leucócitos Mononucleares/transplante , Transplante de Pele/imunologia , Transplante Heterólogo/imunologia , Animais , Teste de Histocompatibilidade , Humanos , Camundongos , Camundongos SCID , Suínos
8.
J Pathol ; 210(2): 224-33, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16917804

RESUMO

The STAT3 (signal transducers and activators of transcription 3) signalling pathway plays a pivotal role in oncogenesis and appears essential for postnatal maintenance of thymic architecture and thymocyte survival. The association of STAT3 activation with thymic epithelial tumours (TETs) and myasthenia gravis (MG) has not been elucidated. In this study, 118 cases of TET and 25 non-neoplastic thymic tissue samples were evaluated for STAT3 and phospho-STAT3 (pSTAT3) expression immunohistochemically. In addition, 44 normal thymuses of different ages were included for comparison. It was found that STAT3 activation in thymic epithelial cells (TECs), as evidenced by pSTAT3 expression and/or nuclear STAT3, was present in the majority of non-neoplastic thymuses (88%, 22/25), including those from young children, but not in fetal thymus. In thymoma (n = 73), activated STAT3 was noted at a significantly higher frequency in the cases of lymphocyte-rich thymoma (ie types AB, B1, and B2, 46%, 23/50) in comparison with lymphocyte-depleted thymoma (types A and B3, 1/23) (p = 0.009). Thymoma with activated STAT3 tended to present at an earlier stage, show complete resectability and less aggressive behaviour, and have a higher correlation with MG than the STAT3-negative/inactive group (p < 0.05). In contrast, thymic carcinoma with activated STAT3 (14/45, 31%) had significantly higher rates of unresectability, vascular invasion, and regional lymph node metastasis (p < 0.05). These data provide the first evidence that constitutive STAT3 activation is seen in both benign and neoplastic thymic tissue and is associated with the persistence of thymic tissue and the presence of MG. It is likely to be induced by different factors in thymoma and thymic carcinoma.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Neoplasias/metabolismo , Fator de Transcrição STAT3/metabolismo , Neoplasias do Timo/metabolismo , Adolescente , Adulto , Idoso , Envelhecimento/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Técnicas Imunoenzimáticas , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/etiologia , Miastenia Gravis/metabolismo , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Análise de Sobrevida , Timoma/complicações , Timoma/metabolismo , Timoma/patologia , Timo/crescimento & desenvolvimento , Timo/metabolismo , Neoplasias do Timo/complicações , Neoplasias do Timo/patologia , Regulação para Cima
9.
Steroids ; 71(9): 817-27, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16814335

RESUMO

Recently, the endogenous origin of nandrolone (19-nortestosterone) and other 19-norsteroids has been a focus of research in the field of drug testing in sport. In the present study, we investigated metabolites conjugated to a glucuronic acid and to a sulfuric acid in urine following administration of four xenobiotic 19-norsteroids. Adult male volunteers administered a single oral dose (10 mg) of each of four 19-norsteroids. Urinary samples collected from 0 to 120 h were subjected to methanolysis and beta-glucuronidase hydrolysis and were derivatized by N-methyl-N-trimethylsilyltrifluoroacetamide (MSTFA) before gas chromatography-mass spectrometry analysis. We confirmed that 19-norandrosterone (19-NA) and 19-noretiocholanolone (19-NE) were present in both glucuronide (g) and sulfate (s) conjugates and 19-norepiandrosterone (19-NEA) was excreted exclusively as a sulfate fraction in urine of all 19-norsteroids tested. The overall levels of the three metabolites can be ranked as follows: 19-NA(g+s)>19-NE(g+s)>19-NEA(s). The concentration profiles of these three metabolites in urine peaked between 2 to 12h post-administration and declined thereafter until approximately 72-96 h. 19-NA was most prominent throughout the first 24 h post-administration, except for a case in which an inverse relationship was found after 6h post-administration of nandrolone. Furthermore, we found that sulfate conjugates were present in both 19-NA and 19-NE metabolites in urine of all 19-norsteroids tested. The averaged total amounts of metabolites (i.e. 19-NA(s+g)+19-NE(s+g)+19-NEA(s)) excreted in urine were 38.6, 42.9, 48.3 and 21.6% for nandrolone, 19-nor-4-androsten-3,17-dione, 19-nor-4-androsten-3beta,17beta-diol and 19-nor-5-androstene-3beta,17beta-diol, respectively. Results from the excretion studies demonstrate significance of sulfate-conjugated metabolites on interpretation of misuse of the 19-norsteroids.


Assuntos
Estranos/farmacologia , Glucuronatos/urina , Noresteroides/farmacologia , Compostos de Enxofre/urina , Xenobióticos/farmacologia , Administração Oral , Adulto , Calibragem , Dopagem Esportivo , Estranos/administração & dosagem , Glucuronatos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Noresteroides/administração & dosagem , Detecção do Abuso de Substâncias , Compostos de Enxofre/metabolismo , Fatores de Tempo , Xenobióticos/administração & dosagem
10.
Cells Tissues Organs ; 180(4): 195-203, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16330876

RESUMO

The adult spleen is a source of early hematopoietic stem cells (HSC). We therefore studied whether culturing spleen or bone marrow (BM) HSC in medium containing 5-azacytidine could induce a cardiac phenotype. c-kit enrichment and depletion of adult pig spleen and BM mononuclear cells were obtained by magnetic bead separation using biotinylated pig stem cell factor (c-kit ligand). Cells were incubated with 5-azacytidine for 24 h and refreshed with 5-azacytidine-free medium every 48 h. Western blot was used to detect cardiac troponin and myosin heavy chains. Although 5-azacytidine treatment led to the formation of ball-like cell clusters in both c-kit-enriched populations, these clusters showed no rhythmic contractions (beating), as observed by others. Furthermore, neither cardiac troponin nor myosin was detected in cells derived from either source. Our methodology and treatment with 5-azacytidine did not induce cardiac gene expression in porcine HSC derived from either pig spleen or BM.


Assuntos
Azacitidina/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Miocárdio/citologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Baço/efeitos dos fármacos , Baço/metabolismo , Animais , Western Blotting , Células da Medula Óssea/citologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Hematopoese , Separação Imunomagnética , Miosinas/deficiência , Proteínas Proto-Oncogênicas c-kit/genética , Baço/citologia , Suínos , Troponina I/deficiência
12.
Brain Inj ; 19(11): 949-53, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16243749

RESUMO

Other than from the thalamus and sensory cortex, episodic pain is an extremely rare neurological manifestation in the central compartment. This study reports a middle-aged man who experienced an acute onset of episodic oscillatory burning pain restricted to the cheiro-oral region, who was found to have a singular infarct at the left tegmental pons. A close relationship between his pain attack and an elevation of arterial blood pressure was clearly observed. Blood adenohypophyseal hormones and electroencephalogram did not reveal an abnormality in the ictus. Neuroimaging and clinical studies did not support involvement of the thalamus, periaqueductal gray matter, hypothalamus or regional structure. Therefore, episodic pain may be an isolated manifestation with a pontine lesion. A relapsing expansion of focal cerebral oedema with fluid retention may have corresponded to the oscillation of his sensory deficit. This accumulating, devastating calamity by a repetitive and paroxysmal offense after a blood-brain barrier breakdown should be cautiously reviewed.


Assuntos
Infartos do Tronco Encefálico/complicações , Mãos/inervação , Boca/inervação , Dor/etiologia , Doença Aguda , Humanos , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Periodicidade , Ponte , Síndrome
13.
Br J Surg ; 92(11): 1382-7, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16044411

RESUMO

BACKGROUND: The aim of this study was to investigate the hypothesis that outcome following concomitant airway resection is superior to that after shaving of the tumour in patients with airway invasion of thyroid carcinoma. METHODS: The records of 34 patients with thyroid cancer with airway invasion were reviewed retrospectively. In addition to total thyroidectomy, airway resection was performed in 18 patients (group 1), whereas the tumour was shaved away from the airway in the other 16 patients (group 2). 131I was used as postoperative adjuvant therapy in all patients. Metastasis and recurrence of the primary lesion were determined by 131I whole-body scans, serum thyroglobulin levels, and computed tomography or ultrasonography of the neck. RESULTS: In group 1, two anastomotic dehiscences resulted in one death. Patients in group 2 had a higher rate of local recurrence (relative risk 8.0, P = 0.013) and earlier recurrence (mean(s.e.m.) 2.6(0.8) versus 7.0(1.1) years; P = 0.026) than those in group 1. Median survival was 5.8 and 4.3 years in the 18 patients of group 1 and 16 patients of group 2 (P = 0.259), and the respective 5-year survival rates were 88 and 84 per cent (P = 0.783). CONCLUSION: Aggressive airway resection can minimize local recurrence of thyroid carcinoma with airway invasion.


Assuntos
Neoplasias Brônquicas/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Brônquicas/mortalidade , Neoplasias Brônquicas/patologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/prevenção & controle , Análise de Sobrevida , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/patologia , Resultado do Tratamento
14.
Transplant Proc ; 37(1): 489-90, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15808685

RESUMO

Hearts from alpha1,3-Galactosyltransferase gene-knockout (GaIT-KO) pigs were transplanted heterotopically into 8 baboons that received an anti-CD154 monoclonal antibody (mAb)-based immunosuppressive regimen and heparin. Three baboons died or were euthanized with beating grafts on 16, 23, and 56 days, respectively, and the remaining 5 grafts functioned for 59-179 days. Hyperacute rejection did not occur, and classical features of acute humoral xenograft or acute cellular rejection were rare. However, thrombotic microangiopathy (TM) developed in all cases; its onset was delayed in 2 baboons that received aspirin. Function of a pig organ in a baboon for a period approaching 6 months has not been reported previously and lends encouragement that the barriers to xenotransplantation will be overcome, but TM requires investigation.


Assuntos
Aspirina/uso terapêutico , Fibrinolíticos/uso terapêutico , Galactosiltransferases/deficiência , Galactosiltransferases/genética , Deleção de Genes , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/métodos , Trombose/prevenção & controle , Transplante Heterólogo/métodos , Animais , Sobrevivência de Enxerto , Papio , Suínos
15.
J Heart Lung Transplant ; 24(1): 92-4, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15653386

RESUMO

Troponin T levels have been monitored in baboons (n = 8) undergoing pig heterotopic heart transplantation, and correlated with a decrease in graft contractions and graft survival. Pig heart graft survival was from 12 to 139 days (mean 45, median 33), and graft failure was associated with predominant thrombotic microangiopathy and ischemia, with focal hemorrhage, and edema. An increase in troponin T levels 5 to 6 days before graft failure correlated closely with diminished graft contractions. An increase in troponin T was a reliable indicator that graft dysfunction was occurring.


Assuntos
Transplante de Coração , Transplante Heterotópico , Troponina T/metabolismo , Animais , Biomarcadores/sangue , Isquemia Fria , Sobrevivência de Enxerto/fisiologia , Modelos Cardiovasculares , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Papio , Suínos
16.
Xenotransplantation ; 11(4): 361-70, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15196131

RESUMO

BACKGROUND: Successful hematopoietic cell allotransplantation results in donor-specific tolerance, but this approach has been unsuccessful in the wild-type pig-to-baboon xenotransplantation model, as pig cells were lost from the circulation within 5 days. However, after cessation of immunosuppressive therapy on day 28, all baboons demonstrated non-specific unresponsiveness on mixed leukocyte reaction (MLR) for at least 30 days. We have now investigated the transplantation of bone marrow (BM) cells from miniature swine homozygous for alpha1,3-galactosyltransferase gene-knockout (GalT-KO). METHODS: Baboons (n = 3) were pre-treated with whole body and thymic irradiation, anti-thymocyte globulin, and splenectomy, and received immunosuppressive and supportive therapy for 28 days. BM was harvested from GalT-KO swine (n = 3). The baboons were monitored for the presence of pig cells by flow cytometry and colony-forming units (CFUs), and for cellular reactivity by MLR. RESULTS: A mean of 11 x 10(8) BM cells/kg was infused into each baboon. The mean absolute numbers and percentages of pig cells detected in the blood at 2 h and on days 1, 2 and 4, respectively, were 641/microl (9.5%), 132/microl (3.4%), 242/microl (3.9%), and 156/microl (2.9%). One baboon died (from accidental hemorrhage) on day 6, at which time chimerism was present in the blood (2.0%) and BM (6.4%); pig cell engraftment in the BM was confirmed by polymerase chain reaction (PCR) of CFUs. In the two other baboons, blood chimerism was lost after day 5 but returned at low levels (<1%) between days 9 to 16 and 7 to 17, respectively, indicating transient BM engraftment. Both surviving baboons showed non-specific unresponsiveness on MLR until they were euthanized on days 85 and 110, respectively. CONCLUSIONS: By using BM cells from GalT-KO pigs, chimerism was detected at levels comparable with previous studies when 30-fold more growth factor-mobilized peripheral blood progenitor cells had been transplanted. In addition, cellular hyporesponsiveness was prolonged. However, long-term engraftment and chimerism were not achieved.


Assuntos
Transplante de Medula Óssea , Galactosiltransferases/deficiência , Galactosiltransferases/genética , Deleção de Genes , Papio , Suínos , Animais , Animais Geneticamente Modificados , Anticorpos/imunologia , Medula Óssea/imunologia , Transplante de Medula Óssea/imunologia , Quimerismo , Galactosiltransferases/imunologia , Leucócitos/imunologia , Teste de Cultura Mista de Linfócitos , Papio/imunologia , Reação em Cadeia da Polimerase , Suínos/genética , Condicionamento Pré-Transplante , Transplante Heterólogo
18.
Transplantation ; 77(1): 1-5, 2004 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-14724427

RESUMO

The recent availability of pigs homozygous for alpha1,3-galactosyltransferase gene knockout, and improved immunosuppressive regimens that prevent an elicited antibody response, are expected to contribute to significantly increased survival of pig organs transplanted into primates, bringing clinical trials of xenotransplantation closer. Patients highly sensitized to human leukocyte antigens, who may be precluded from obtaining a human donor organ, would be one group that might benefit from xenotransplantation. However, there have been few studies on whether there is cross-reactivity of anti-human leukocyte antigen antibodies with pig antigens. What data there are suggest that such cross-reactivity exists and that this may be detrimental to the outcome after transplantation of a pig organ. Neither is it known whether sensitization after a pig xenograft would preclude subsequent allotransplantation, although the data available suggest that this will not be the case. Further investigation on allo- and xenoantibody cross-reactivity is required.


Assuntos
Anticorpos Heterófilos/imunologia , Reações Cruzadas , Isoanticorpos/imunologia , Imunologia de Transplantes , Animais , Antígenos HLA/imunologia , Humanos , Imunização
19.
Ann Thorac Surg ; 71(5): 1695-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11383833

RESUMO

Theoretically, the jejunum, fasciocutaneous or myocutaneous flap is recommended as an esophageal substitute in redoing reconstruction of the esophagus after a second incidence of corrosive injury. However, other esophageal substitutes should also be considered. We present a case of a 42-year-old woman who underwent esophageal reconstruction using an ileocolon graft for corrosive esophageal stricture ten years before. The patient ingested caustic drain cleaner again and underwent resection of the ileocolon graft secondary to corrosive necrosis. Two and a half months after the second incidence of corrosive injury, reconstruction of the esophagus was again performed using a graft of remnant ileo-left colon aided by microvascular anastomosis. The patient was able to swallow a regular diet after the procedure. Remnant ileo-left colon is a good alternative esophageal substitute in cases of repeated corrosive injury.


Assuntos
Anastomose Cirúrgica/métodos , Queimaduras Químicas/cirurgia , Colo/transplante , Estenose Esofágica/induzido quimicamente , Esofagectomia/métodos , Íleo/transplante , Microcirurgia/métodos , Complicações Pós-Operatórias/cirurgia , Adulto , Cáusticos , Estenose Esofágica/cirurgia , Feminino , Humanos , Necrose , Tentativa de Suicídio
20.
Cancer ; 91(9): 1826-33, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11335910

RESUMO

BACKGROUND: Compared with free drug, sterically stabilized liposomal drug has prolonged circulation time and, thereby, higher tumor selectivity and antitumor activity. The stability in plasma is an important consideration in the formulation of clinically useful liposomal drug. A Phase I study of a stable liposomal doxorubicin with polyethylene glycol (PEG) coating and phospholipid component of distearoyl phosphatidylcholine (DSPC) was performed to characterize its pharmacokinetic properties, toxicity profile, and maximal tolerated dose. METHODS: The starting dose was 30 mg/m(2) every 3 weeks with an increment of 10 mg/m(2) for each level. A cohort of at least three patients was entered for each level. Dose escalation stopped when more than one-third of patients had dose limiting toxicity (DLT), which was equal to or more than Grade 3 nonhematologic toxicity. Blood was sampled immediately before and at 5 minutes, 2 hours, 4 hours, 10 hours, 24 hours, 48 hours, 72 hours, and 168 hours after the completion of PEGylated liposomal doxorubicin (PLD) infusion. Plasma level of doxorubicin was determined with fluorometry, and the pharmacokinetic properties were analyzed. RESULTS: Twenty-six patients were entered, and 101 courses were studied. This DSPC PLD had a steady-state distribution volume (Vss) of 2.4 +/- 0.9 liters (mean +/- standard deviation), a clearance of 0.027 +/- 0.010 liters per hour, and a beta half-life of 65.0 +/- 17.8 per hour. These characteristics were dose independent, and the Vss and clearance were smaller than those of a well characterized PLD comprised of hydrogenated soybean phosphatidylcholine (HSPC). At the dose level of 50 mg/m(2), its plasma area under the concentration time curve was approximately twice that of HSPC PLD. Attenuation of acute toxicity, such as nausea, emesis, and alopecia, was noted in all dose levels. However, stomatitis was common from the dose level of 30 mg/m(2), and its incidence and severity increased with dosage and became dose limiting at 50 mg/m(2). A dose of 45 mg/m(2) every 3 weeks was then given in eight patients, and the side effects were acceptable. This dose was recommended for Phase II clinical trials. Fourteen of 17 patients with a dose level > or = 40 mg/m(2) were evaluable for response, but none achieved partial remission. CONCLUSIONS: This DSPC PLD had the characteristics of second-generation liposomal drug pharmacokinetically and toxicologically. The incidence of severe stomatitis was higher than that of HSPC PLD, corresponding to the difference in pharmacokinetics. Only limited antitumor activity was observed, although defining its therapeutic application will need further Phase II studies. Further prolongation of plasma stability of PLD may not be clinically beneficial considering the increased stomatitis and the reduced achievable dose intensity.


Assuntos
Antineoplásicos/farmacocinética , Doxorrubicina/farmacocinética , Neoplasias/metabolismo , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Leucopenia/etiologia , Lipossomos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Resultado do Tratamento
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