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1.
Transplant Proc ; 38(10): 3289-92, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17175252

RESUMEN

A 50% to 75% early graft loss upon engraftment has been suggested to in intraportal islet transplantation (IPIT). Hypoxia in the portal vein contributes to graft loss in immediately posttransplantation. Herein we examined the effect on the outcome of IPIT of intraperitoneal oxygenated perfluorochemical (PFC) as an oxygen carrier. Isolated Lewis rat islets were transplanted into the portal vein of a chemically induced diabetic syngeneic rat. First, 1500 IEQ was determined to be the optimal dose in this study. When oxygenated PFC (group 1) was intraperitoneally injected following IPIT of 1500 IEQ, the success rate of transplantation was 5/6, in contrast to 1/6 when PFC with no oxygen was injected (group 2) and 1/6 in IPIT without PFC, respectively. The area under the glucose profile curve on intraperitoneal glucose tolerance tests on posttransplant day 28 in group 1 was significantly smaller than that for group 2. In conclusion, intraperitoneal oxygenated PFC improved the outcome of IPIT.


Asunto(s)
Diabetes Mellitus Experimental/cirugía , Trasplante de Islotes Pancreáticos/métodos , Oxígeno/administración & dosificación , Sistema Porta , Animales , Glucemia/metabolismo , Fluorocarburos/uso terapéutico , Supervivencia de Injerto/efectos de los fármacos , Inyecciones Intraperitoneales , Trasplante de Islotes Pancreáticos/fisiología , Modelos Animales , Ratas , Ratas Endogámicas Lew , Trasplante Isogénico , Resultado del Tratamiento
2.
Transplant Proc ; 37(8): 3430-2, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16298618

RESUMEN

BACKGROUND: Young donors, donors with low body mass index (BMI), and non-heart-beating (NHB) donors are considered nonideal for islet transplantation. In this report, we successfully used a pancreas from a young, low-BMI, NHB donor for islet transplantation. METHODS: The donor was a 15-year-old adolescent boy whose cause of death was rupture of a primary brain tumor. According to Japanese regulations, his pancreas was procured after cardiac arrest. Warm ischemic time was 3 minutes and cold ischemic time was 300 minutes. The pancreas was digested by the automated method of Ricordi, followed by purification using continuous Euro-Ficoll gradients on a Cobe 2991 device. The recipient was a 35-year-old woman with unstable type 1 diabetes mellitus. Her pretransplant C-peptide level was null. She suffered frequent hypoglycemic unawareness. Her pretransplant M value, which is a good marker for glucose instability, was 125. Islet yield was 252,816 IEQ. There were no signs of contamination. Viability of islets assessed by FDA/PI staining was 83%. Stimulation index was 2.7. RESULTS: The patient received 5160 IEQ/kg of islets via the portal vein under local anesthesia. There were no transplant-related complications. Although she required minimal exogenous insulin, her C-peptide level increased to 0.7 ng/mL at postoperative day (POD) 14. Her M value at POD 15 to 19 decreased dramatically to 23.6, indicating good glycemic control. At 3 months posttransplant, episodes of hypoglycemia disappeared. CONCLUSIONS: Although an additional transplant is mandatory to wean patients from insulin, this case shows the possibility of using marginal donors, such as a young, low-BMI, NHB donor, for pancreas islet transplantation.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Trasplante de Islotes Pancreáticos/fisiología , Recolección de Tejidos y Órganos/métodos , Adolescente , Glucemia/metabolismo , Muerte Encefálica , Diabetes Mellitus Tipo 1/sangre , Paro Cardíaco , Humanos , Masculino , Soluciones Preservantes de Órganos , Pancreatectomía , Resultado del Tratamiento
3.
Transplant Proc ; 37(1): 220-2, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15808600

RESUMEN

BACKGROUND: Recently, preservation using oxygenated perfluorocarbon (the two-layer method) has shown beneficial effects on islet yield and viability. In this paper, we apply this concept on isolation processes to examine the effectiveness of oxygenation. METHODS: Rat pancreata were digested using four different methods: (groups 1A, 1B, 2A, and 2B) with or without oxygenated perfluorocarbon in groups 1 and 2, respectively. Adenosine was added into the collagenase solution in subgroup A whereas it is not added in subgroup B. RESULTS: Tissue oxygen tension in group 1 was about 0 during digestion; whereas it rapidly reached about 300 mm Hg and was maintained in group 2. Tissue ATP level just after laparotomy (control) was 4.2 +/- 0.7 micromol/g dry weight. The ATP levels after digestion were 0.12 +/- 0.03 in group 1A (P < 0.01 vs control); 0.70 +/- 0.10 in group 1B (P < 0.01 vs control); 0.30 +/- 0.18 in group 2A (P < 0.01 vs control); and 2.90 +/- 0.80 in group 2B (P = 0.19 vs control). Islet yields (IEQ/pancreas) were 1600 +/- 400 in group 1B; 1400 +/- 400 in group 1B; 1300 +/- 400 in group 2A; and 2400 +/- 100 in group 2B. The amount in group 2B was significantly greater than that in the other three groups. CONCLUSIONS: Oxygen provision by preoxygenated perfluorocarbon itself showed no beneficial effect on islet yield. However, if oxygen provision was associated with adenosine administration into the pancreas, tissue ATP levels after digestion were well maintained, and a greater number of islets were retrieved.


Asunto(s)
Adenosina Trifosfato/metabolismo , Fluorocarburos/farmacología , Islotes Pancreáticos/citología , Animales , Separación Celular/métodos , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Masculino , Consumo de Oxígeno , Pancreatectomía , Ratas , Ratas Endogámicas Lew
4.
J Neurosci Res ; 80(2): 182-90, 2005 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15772979

RESUMEN

Recent studies have shown that delayed transplantation of neural stem/progenitor cells (NSPCs) into the injured spinal cord can promote functional recovery in adult rats. Preclinical studies using nonhuman primates, however, are necessary before NSPCs can be used in clinical trials to treat human patients with spinal cord injury (SCI). Cervical contusion SCIs were induced in 10 adult common marmosets using a stereotaxic device. Nine days after injury, in vitro-expanded human NSPCs were transplanted into the spinal cord of five randomly selected animals, and the other sham-operated control animals received culture medium alone. Motor functions were evaluated through measurements of bar grip power and spontaneous motor activity, and temporal changes in the intramedullary signals were monitored by magnetic resonance imaging. Eight weeks after transplantation, all animals were sacrificed. Histologic analysis revealed that the grafted human NSPCs survived and differentiated into neurons, astrocytes, and oligodendrocytes, and that the cavities were smaller than those in sham-operated control animals. The bar grip power and the spontaneous motor activity of the transplanted animals were significantly higher than those of sham-operated control animals. These findings show that NSPC transplantation was effective for SCI in primates and suggest that human NSPC transplantation could be a feasible treatment for human SCI.


Asunto(s)
Trasplante de Tejido Fetal/métodos , Neuronas/trasplante , Traumatismos de la Médula Espinal/terapia , Médula Espinal/trasplante , Trasplante de Células Madre/métodos , Trasplante Heterólogo/métodos , Animales , Callithrix , Diferenciación Celular/fisiología , Células Cultivadas , Vértebras Cervicales , Femenino , Humanos , Neuronas/citología , Recuperación de la Función/fisiología , Médula Espinal/citología , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/rehabilitación
5.
J Neurosci Res ; 80(2): 172-81, 2005 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15772980

RESUMEN

Most previous studies on spinal cord injury (SCI) have used rodent models. Direct extrapolation of the results obtained in rodents to clinical cases is difficult, however, because of neurofunctional and anatomic differences between rodents and primates. In the present study, the development of histopathologic changes and functional deficits were assessed quantitatively after mild, moderate, and severe spinal cord contusive injuries in common marmosets. Contusive SCI was induced by dropping one of three different weights (15, 17, or 20 g) at the C5 level from a height of 50 mm. Serial magnetic resonance images showed significant differences in the intramedullary T1 low signal and T2 high signal areas among the three groups. Quantitative histologic analyses revealed that the number of motor neurons, the myelinated areas, and the amounts of corticospinal tract fibers decreased significantly as the injury increased in severity. Motor functions were evaluated using the following tests: original behavioral scoring scale, measurements of spontaneous motor activity, bar grip test, and cage-climbing test. Significant differences in all test results were observed among the three groups. Spontaneous motor activities at 10 weeks after injury were closely correlated with the residual myelinated area at the lesion epicenter. The establishment of a reliable nonhuman primate model for SCI with objective functional evaluation methods should become an essential tool for future SCI treatment studies. Quantitative behavioral and histopathologic analyses enabled three distinct grades of injury severity (15-g, 17-g, and 20-g groups) to be characterized with heavier weights producing more serious injuries, and relatively constant behavioral and histopathologic outcomes.


Asunto(s)
Callithrix , Modelos Animales de Enfermedad , Enfermedades de los Monos/patología , Traumatismos de la Médula Espinal/patología , Animales , Callithrix/fisiología , Vértebras Cervicales , Femenino , Destreza Motora/fisiología , Recuperación de la Función/fisiología , Traumatismos de la Médula Espinal/rehabilitación , Factores de Tiempo
6.
Endoscopy ; 36(2): 183-5, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14765318

RESUMEN

Dieulafoy's lesion is an arterial malformation in the subumucosal layer of the gastrointestinal tract that can cause massive bleeding. The esophagus is not a common location for this lesion. We present here a first report of Dieulafoy's lesion of the esophagus correctly diagnosed and successfully treated by the endoscopic injection of N-butyl-2-cyanoacrylate.


Asunto(s)
Malformaciones Arteriovenosas/diagnóstico , Enbucrilato/análogos & derivados , Enbucrilato/administración & dosificación , Esófago/irrigación sanguínea , Hemorragia Gastrointestinal/terapia , Hemostasis Endoscópica/métodos , Adhesivos Tisulares/administración & dosificación , Anciano , Arterias/anomalías , Malformaciones Arteriovenosas/complicaciones , Malformaciones Arteriovenosas/terapia , Diagnóstico Diferencial , Hemorragia Gastrointestinal/etiología , Hematemesis/etiología , Hematemesis/terapia , Humanos , Masculino , Resultado del Tratamiento
7.
Br J Cancer ; 89(11): 2116-21, 2003 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-14647147

RESUMEN

If oesophageal carcinoma is detected in the superficial stage, the prognosis is better than for advanced oesophageal carcinoma. But the factors which predict the prognosis and treatment policy remain unclear. Matrix metalloproteinase-7 (MMP-7) and matrix metalloproteinase-9 (MMP-9) have been reported to have close associations with tumour invasion and metastasis. In this study, we retrospectively studied the relations between MMP-7 and MMP-9 expression in immunohistochemistry, clinicopathologic factors, and prognosis in 55 superficial oesophageal carcinomas. MMP-7 and MMP-9 expression occurred in 23.6% and 47.3% of the patients, respectively. MMP-7 expression was significantly correlated with the presence of nodal metastasis (P=0.004). MMP-9 expression was significantly correlated with the depth of tumour invasion (P=0.004), lymphatic permeation (P=0.001), nodal metastasis (P=0.049), and pathologic differentiation grade (P=0.003). By the log-rank test, MMP-7 expression and MMP-9 expression on the invasive front were related to the prognosis. In multivariate analysis, MMP-9 expression on the invasive front was an independent prognostic indicator. The combined expression of MMP-7 and MMP-9 may be a good marker for the degree of malignancy of oesophageal cancer and for the presence of lymphatic metastasis.


Asunto(s)
Adenocarcinoma/enzimología , Carcinoma de Células Escamosas/enzimología , Neoplasias Esofágicas/enzimología , Metaloproteinasa 7 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Adulto , Anciano , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia
8.
Br J Surg ; 90(8): 1015-20, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12905558

RESUMEN

BACKGROUND: Intestinal ischaemia-reperfusion (IR) injury frequently occurs in abdominal surgery. Perfluorochemical (PFC) can be used to oxygenate intestinal organs directly and allows adenosine 5'-triphosphate (ATP) production within the submerged organs during ischaemia. This study was designed to evaluate the protective effect of PFC in IR injury, focusing on cytokine production in rat small intestine. METHODS: The superior mesenteric artery was occluded in rats for 60 min and the small bowel placed in an intestinal bag containing either normal saline (group 1), oxygenated saline (group 2) or oxygenated PFC (group 3). The arterial clip was subsequently removed, allowing reperfusion. The number of rats that survived for 7 days, tissue ATP levels, biochemical variables, tissue lipid peroxidation (LPO), bacterial cultures and histological changes were examined after reperfusion. RESULTS: The use of oxygenated PFC in group 3 improved survival compared with the other groups. Serum creatine phosphokinase and lactate dehydrogenase levels in groups 1 and 2 reflected small intestinal damage, and plasma levels of tumour necrosis factor alpha and interleukin 6 were raised. In contrast, oxygenated PFC decreased these levels, and reduced LPO, bacterial translocation and augmented apoptosis of the small intestine after reperfusion. CONCLUSION: An intestinal bag containing oxygenated PFC showed protective effects during bowel ischaemia.


Asunto(s)
Fluorocarburos/uso terapéutico , Intestino Delgado/irrigación sanguínea , Isquemia/prevención & control , Daño por Reperfusión/prevención & control , Adenosina Trifosfato/metabolismo , Animales , Creatina Quinasa/sangre , Peroxidación de Lípido , Masculino , Ratas , Ratas Wistar , Análisis de Supervivencia , Factor de Necrosis Tumoral alfa/análisis
10.
J Androl ; 22(6): 953-60, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11700859

RESUMEN

The expression of inhibin subunits in the testes of the Göttingen miniature pig was examined by in situ hybridization and immunohistochemistry. In addition, the major forms were determined by enzyme-linked immunosorbent assay (ELISA). Strong positive immunostaining for the inhibin alpha subunit was observed in Sertoli and late-stage germ cells, but it was weak in Leydig cells. However, Leydig cells showed strong positive staining for the betaA subunit, but Sertoli cells and spermatogonia showed a weak reaction. Strong positive immunostaining for the betaB subunit was observed in Leydig cells but spermatogonia showed weak staining for it. In contrast to the staining specificity of inhibin alpha and betaA subunits, the betaB subunit did not exhibit positive staining in Sertoli cells. In situ hybridization revealed that although the a subunit mRNA signal was highly expressed in all cell types, the reaction appeared to be stronger in Sertoli cells and spermatogonia than in Leydig cells. betaA subunit mRNA expression was somewhat identical to that of the alpha subunit, however, germ cells showed a weak stain for it. A strong, positive mRNA signal for the betaB subunit was confined to Leydig cells and late-stage germ cells. ELISA results showed that concentrations of inhibin B and inhibin pro-alphaC were high in the circulation and testes. In contrast, inhibin A levels in both plasma and testes were undetectable. The present results strongly suggest that inhibin B is the major form of circulating inhibin and that Leydig cells are the predominant source of this dimeric inhibin in male Göttingen miniature pigs. Furthermore, the germ cells also appear to be an important source of circulating inhibins.


Asunto(s)
Inhibinas/genética , Células Intersticiales del Testículo/fisiología , Animales , Regulación del Desarrollo de la Expresión Génica , Inmunohistoquímica , Masculino , Subunidades de Proteína , ARN Mensajero/genética , Células de Sertoli/fisiología , Espermatogonias/fisiología , Porcinos , Porcinos Enanos , Testículo/crecimiento & desarrollo , Transcripción Genética
11.
Pancreas ; 23(4): 393-8, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11668209

RESUMEN

INTRODUCTION: Recently, results of the clinical application of the two-layer method have shown the morphologic quality of the human pancreas grafts after reperfusion to be excellent, although ischemia-reperfusion injury is related to early graft loss in pancreas transplantation. However, some reports have indicated that heat shock proteins (HSPs) have important functions in response to the stress-related events. AIM: To examine whether the two-layer method reduced ischemia-reperfusion injury in a canine pancreas autotransplantation model by investigating the expression of HSPs. METHODOLOGY: There were three experimental groups in which dogs received segmental autografts after preservation by the two-layer method using University of Wisconsin solution (UW) (group 1), simple storage in UW (group 2) for 24 hours, or no preservation (group 3). RESULTS: In group 1, pancreatic tissue perfusions were high, and pancreatic exocrine functions were well preserved after 1, 2, and 4 hours of reperfusion with low incidence of graft pancreatitis or vessel thrombosis compared with that in group 2. Moreover, ATP rapidly recovered, and HSP 60 was strongly enhanced after reperfusion in group 1. On the other hand, ATP recovery and the enhancement of HSP 60 were weak after reperfusion in group 2. CONCLUSION: The two-layer method reduced ischemia-reperfusion injury compared with UW simple storage in canine pancreas autotransplantation with a strong expression of HSP 60.


Asunto(s)
Chaperonina 60/fisiología , Trasplante de Páncreas , Páncreas/irrigación sanguínea , Daño por Reperfusión/prevención & control , Adenosina Trifosfato/metabolismo , Amilasas/sangre , Animales , Chaperonina 60/análisis , Perros , Femenino , Supervivencia de Injerto , Proteínas HSP90 de Choque Térmico/análisis , Inmunohistoquímica , Lipasa/sangre , Masculino , Páncreas/química , Páncreas/enzimología , Trasplante Autólogo
12.
Hepatogastroenterology ; 48(40): 1157-61, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11490823

RESUMEN

BACKGROUND/AIMS: Our objectives in this study were to evaluate the surgical treatment for mucin-producing tumor of the pancreas from the clinicopathological and imaging features. METHODOLOGY: Thirty-one patients with mucin-producing tumor of the pancreas were examined based on clinicopathological analyses to determine the appropriate surgical treatment. RESULTS: The clinical and imaging features easily distinguished the main duct type of intraductal papillary lesions (type Ia), branch type of intraductal papillary lesions (type Ib) and mucinous cystic neoplasms (type II). From pathological examinations, a dilated main pancreatic duct had the malignant potentiality and multicentric development. CONCLUSIONS: Pancreatic segments containing a dilated main pancreatic duct should be resected in type Ia. Type Ib is sufficient for partial resection without lymphadenectomy. Type II also requires partial resection of the cystic neoplasm. A standard lymphadenectomy may be an option when type Ia and II show invasive features.


Asunto(s)
Neoplasias Pancreáticas/cirugía , Adenocarcinoma Mucinoso/cirugía , Adenoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Ductal Pancreático/cirugía , Colangiopancreatografia Retrógrada Endoscópica , Duodenoscopía , Femenino , Humanos , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad
13.
Eur J Haematol ; 66(4): 272-80, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11380607

RESUMEN

To establish a new non-human primate model for human cytokine and gene therapy, we characterized lymphocytes and haematopoietic progenitor cells of the small New World monkey, the common marmoset. We first assessed the reactions of marmoset bone marrow (BM) and peripheral blood (PB) cells to mouse anti-human monoclonal antibodies (mAbs) for the purpose of isolating marmoset lymphocytes and haematopoietic progenitor cells. Both cell fractions stained with CD4 and CD8 mAbs were identified as lymphocytes by cell proliferation assay and morphological examination. Myeloid-specific mAbs such as CD14 and CD33 did not react with marmoset BM and PB cells. No available CD34 and c-kit mAbs could be used to purify the marmoset haematopoietic progenitor cells. Furthermore, we studied the in vitro transduction of the bacterial beta-galactosidase (LacZ) gene into CFU-GM derived from marmoset BM using retroviral and adenoviral vectors. The transduction efficiency was increased by using a mixed culture system consisting of marmoset BM stromal cells and retroviral producer cells. It was also possible to transduce LacZ gene into marmoset haematopoietic progenitor cells with adenoviral vectors as well as retroviral vectors. The percentage of adenovirally transduced LacZ-positive clusters was 15% at day 4 (multiplicity of infection=200), but only 1-2% at day 14. The differential use of viral vector systems is to be recommended in targeting different diseases. Our results suggested that marmoset BM progenitor cells were available to examine the transduction efficiency of various viral vectors in vitro.


Asunto(s)
Callithrix , Células Madre Hematopoyéticas/metabolismo , Transducción Genética/métodos , Adenoviridae/genética , Animales , Anticuerpos Monoclonales , Células de la Médula Ósea/citología , Células de la Médula Ósea/inmunología , Reacciones Cruzadas/inmunología , Femenino , Vectores Genéticos/normas , Células Madre Hematopoyéticas/inmunología , Humanos , Operón Lac/genética , Linfocitos/inmunología , Masculino , Modelos Animales , Retroviridae/genética
14.
Hepatogastroenterology ; 48(38): 574-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11379357

RESUMEN

There have been disappointingly few effective treatment modalities for multiple liver metastases from pancreatic cancer. Percutaneous isolated hepatic perfusion, which was developed by us for delivering dose-intensive chemotherapy to the liver, has a high efficacy in the majority of patients with multiple primary and secondary liver tumors. We herein report the first experience of a two-stage treatment with extended local resection and subsequent two percutaneous isolated hepatic perfusions for advanced pancreatic ductal adenocarcinoma with liver metastases. The second percutaneous isolated hepatic perfusion with high-dose cisplatin and mitomycin G demonstrated a distinct regression of metastatic liver tumors. Although a long-term patient survival was not obtained due to local recurrence, liver metastases have been well controlled ever since. Given that further studies establish the efficacy of percutaneous isolated hepatic perfusion also in this field, this modality would be used as prophylaxis as well as treatment of liver metastasis in patients with advanced pancreatic ductal adenocarcinoma.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma Ductal Pancreático/secundario , Carcinoma Ductal Pancreático/cirugía , Quimioterapia del Cáncer por Perfusión Regional , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Pancreatectomía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Antígeno CA-19-9/sangre , Antígeno Carcinoembrionario/sangre , Carcinoma Ductal Pancreático/sangre , Carcinoma Ductal Pancreático/diagnóstico por imagen , Humanos , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/sangre , Esplenectomía , Tomografía Computarizada por Rayos X
15.
Jpn J Pharmacol ; 85(1): 41-6, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11243573

RESUMEN

The effects of purinoceptor agonists on noradrenaline NA release by electrical stimulation in rat mesenteric arteries were examined to clarify the pharmacological properties of prejunctional purinoceptors on adrenergic nerves. Adenosine and the other P1-receptor agonists, 5'-(N-ethylcarboxamido) adenosine and 2-chloroadenosine, significantly inhibited the release of NA. Also beta,gamma-methylene ATP and 2-methylthio ATP, P2-receptor agonists, significantly inhibited NA releases. The inhibitory effect of adenosine was significantly reduced by adenosine deaminase, but those of beta,gamma-methylene ATP and 2-methylthio ATP were not affected. This suggests that the inhibitory effects of P2-receptor agonists are not due to conversion into adenosine. 1,3-Dipropyl-8-cyclopentylxanthine (DPCPX), a P1 (A1)-receptor antagonist, significantly reduced the inhibitory effects of not only the P1- but also P2-receptor agonists. Therefore, DPCPX appears to act on both prejunctional P1- and P2-receptor as an antagonist. Pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS), a P2-receptor antagonist, significantly reduced the inhibitory effects of the P2-receptor agonists, but not those of the P1-receptor agonists. From these findings in the rat mesenteric artery, the P1-receptor agonist-induced inhibition of NA-release appears to be mediated via a well-known prejunctional P1-receptor of the A1-subtype, but the P2-receptor agonist-induced inhibition appears to be mediated via an unidentified purinoceptor that is blocked not only by P2-receptor antagonists but also by P1-receptor antagonists.


Asunto(s)
Arterias Mesentéricas/efectos de los fármacos , Norepinefrina/metabolismo , Agonistas del Receptor Purinérgico P1 , Agonistas del Receptor Purinérgico P2 , 2-Cloroadenosina/farmacología , Adenosina/análisis , Adenosina/farmacología , Adenosina Desaminasa/farmacología , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/farmacología , Adenosina-5'-(N-etilcarboxamida)/farmacología , Animales , Clonidina/farmacología , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica , Técnicas In Vitro , Masculino , Arterias Mesentéricas/inervación , Arterias Mesentéricas/metabolismo , Antagonistas de Receptores Purinérgicos P1 , Antagonistas del Receptor Purinérgico P2 , Fosfato de Piridoxal/análogos & derivados , Fosfato de Piridoxal/farmacología , Ratas , Ratas Wistar , Tetrodotoxina/farmacología , Xantinas/farmacología
18.
J Mol Evol ; 51(3): 214-22, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11029066

RESUMEN

A New World monkey, the common marmoset (Callithrix jacchus), will be used as a preclinical animal model to study the feasibility of cell and gene therapy targeting immunological and hematological disorders. For elucidating the immunogenetic background of common marmoset to further studies, in the present study, polymorphisms of MHC-DRB genes in this species were examined. Twenty-one Caja-DRB exon 2 alleles, including seven new ones, were detected by means of subcloning and the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) methods followed by nucleotide sequencing. Based on the alignment of these allele sequences, we designed two pairs of specific primers and established a PCR-SSCP method for DNA-based histocompatibility typing of the common marmoset. According to the family segregation data and phylogenetic analyses, we presumed that Caja-DRB alleles could be classified into five different loci. Southern blotting analysis also supported the existence of multiple DRB loci. The patterns of nucleotide substitutions suggests that positive selection operates in the antigen-recognition sites of Caja-DRB genes.


Asunto(s)
Callithrix/genética , Callithrix/inmunología , Genes MHC Clase II , Polimorfismo Genético , Alelos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cartilla de ADN/genética , Evolución Molecular , Exones , Femenino , Masculino , Datos de Secuencia Molecular , Linaje , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Homología de Secuencia de Aminoácido
19.
Pancreas ; 21(3): 305-9, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11039476

RESUMEN

Hypothermia causes vascular endothelial damage that leads to graft microcirculation disorder and eventually thrombosis after reperfusion. The two-layer cold storage method (TL) was previously demonstrated to supply oxygen to the pancreas graft and maintain high adenosine triphosphate tissue concentration. In this study, we evaluated whether mild hypothermic (20 degrees C) preservation using the TL method could reduce endothelial damage while maintaining parenchymal viability. Graft survival by 20 degrees C preservation was investigated using a dog segmental pancreas autotransplantation model (simple storage in University of Wisconsin solution (UW) for 5 and 8 hours or TL for 5, 8, 12, and 24 hrs. respectively). Subsequently, the grafts were preserved in four different conditions (4 and 20 degrees C UW. 4 and 20 degrees C TL) for 8 hours to evaluate microvascular endothelial damage. Trypan blue uptake of vascular endothelium and pancreatic tissue perfusion were evaluated. No graft preserved by 20 degrees C UW for 5 and 8 hours survived (0/7 and 0/4). In contrast, the graft survival rates by 20 degrees C TL for 5, 8, 12, and 24 hours were 100% (5/5), 80% (4/5), 20% (1/5), and 0% (0/4), respectively. In trypan blue uptake analysis, there were significant differences between 4 and 20 degrees C in both UW and TL (4 degrees C UW, 37% [n = 5) vs. 20 degrees C UW, 13% [n = 4] [p < 0.01]; 4 degrees C TL, 29% [n = 5] vs. 20 degrees C TL, 10% [n = 5] [p < 0.011). The perfusion values in 20 degrees C TL were significantly higher than those in other groups at least for up to 120 minutes after reperfusion (p < 0.01 ). In short-term pancreas preservation, mild hypothermic TL reduced vascular endothelial cell damage and ameliorated graft microcirculation while maintaining parenchymal viability. Mild hypothermic TL may lessen vascular complications in clinical pancreas transplantation when used for several-hour preservation.


Asunto(s)
Frío , Microcirculación/fisiología , Trasplante de Páncreas , Páncreas/irrigación sanguínea , Conservación de Tejido/métodos , Animales , Presión Sanguínea , Perros , Endotelio Vascular/fisiología , Supervivencia de Injerto , Trasplante Autólogo , Azul de Tripano/metabolismo
20.
Transplantation ; 70(5): 771-4, 2000 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-11003355

RESUMEN

BACKGROUND: The two-layer method [University of Wisconson solution (UW)/perfluorochemical plus O2] for pancreas preservation has been demonstrated to be superior to simple UW storage alone in the canine model. For the first time, we applied the two-layer method to clinical whole-pancreas transplantation. METHODS: Pancreases were placed in the two-layer method in 10 cases and UW alone in 44 cases before transplant. The mean cold ischemic time was 16.5 hr in the two-layer group versus 18.1 hr in the UW group (P=NS). We compared the condition of graft at the time of reperfusion, and then 3 months posttransplant graft function and complications. RESULTS: At the time of reperfusion, no grafts in the two-layer group were edematous, compared with 10(23.3%) of 43 in the UW group (P=0.18). Seven (70%) of 10 grafts in the two-layer group obtained the best overall quality score, compared with 24(57.1%) of 42 in the UW group (P=0.72). Nine (90%) of 10 recipients in the two-layer group became insulin-independent during hospitalization, compared with 31(70.5%) of 44 in the UW group (P=0.26). Time to insulin independence was no different between the two groups. No pancreas grafts preserved by the two-layer method suffered acute rejection. Conclusions. The two-layer preservation method is feasible in human clinical transplantation. It was at least equivalent and may be superior to UW alone in both morphologic and functional assessment of the transplanted pancreas.


Asunto(s)
Soluciones Preservantes de Órganos , Preservación de Órganos/métodos , Páncreas , Adenosina/farmacología , Adolescente , Adulto , Alopurinol/farmacología , Índice de Masa Corporal , Femenino , Fluorocarburos/farmacología , Glutatión/farmacología , Humanos , Insulina/farmacología , Masculino , Persona de Mediana Edad , Oxígeno/farmacología , Trasplante de Páncreas , Rafinosa/farmacología , Factores de Tiempo
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