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1.
Intern Med ; 62(2): 233-235, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35732453

RESUMEN

A 77-year-old man presented with abdominal pain for 1 week. He was taking enteric-coated low-dose aspirin (LDA) to prevent secondary cardiovascular events and a proton pump inhibitor (PPI). Computed tomography indicated a small intestinal perforation; thus, small intestine resection was performed. Two months after surgery, he experienced a recurrence of the perforation. Since his repeated perforation was suspected to be due to LDA, LDA was discontinued. He has experienced no further recurrence since then. This is the first case of small intestinal perforation caused by enteric-coated LDA. Enteric-coated LDA may cause small intestinal perforation in patients with severe atherosclerosis under PPI administration.


Asunto(s)
Perforación Intestinal , Masculino , Humanos , Anciano , Perforación Intestinal/inducido químicamente , Perforación Intestinal/diagnóstico por imagen , Perforación Intestinal/cirugía , Aspirina/efectos adversos , Inhibidores de la Bomba de Protones/efectos adversos , Dolor Abdominal
2.
Arch Acad Emerg Med ; 7(1): e67, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32021978

RESUMEN

Although fatalities due to caffeine intoxication are uncommon, a caffeine overdose may cause profound toxicity, resulting in tachycardia, arrhythmia, convulsions, vomiting, coma, and possibly death. In particular, high caffeine consumption while pregnant can cause increased fetal catecholamine levels, which could lead to increased fetal heart rate and placental vasoconstriction and impair fetal oxygenation. Therefore, caffeine intoxication in pregnant women should be treated immediately. Herein, we present a 33-year-old pregnant woman who was treated in our department after ingesting 4000mg of caffeine in an attempt to commit suicide. We successfully treated our patient, and she delivered a healthy baby at 38 weeks.

3.
Am J Emerg Med ; 34(2): 123-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26573783

RESUMEN

INTRODUCTION: Among elderly patients with severe trauma, the sites of massive hemorrhage and their clinical characteristics are not well understood. Therefore, we investigated the sites of massive hemorrhage in patients with severe trauma, and compared the results for younger and elderly patients. METHODS: A cohort of severe trauma patients (Injury Severity Score ≥16) admitted from March 2007 to December 2014 was reviewed retrospectively. The inclusion criterion was massive bleeding, which was defined as bleeding that required the transfusion of ≥10 red cell concentrate units within 24 hours of admission, or as cases of early death that occurred despite continuous blood transfusion and before the patient could receive ≥10 red cell concentrate units within the first 24 hours after their admission. RESULTS: Eighty-four patients met our inclusion criterion. The younger group (<65 years old) included 40 patients (48%), whereas the older group (≥65 years old) included 44 patients (52%). The percentage of nondiagnosable cases at the primary survey (massive bleeding due to multisite damage caused by a bone fracture or contusion, retroperitoneal hematoma without a pelvic ring fracture and with stable pelvic ring fracture) was 14% in the younger group and 40% in the older group (odds ratio, 3.92; 95% confidence interval, 1.37-11.27, P = .017). CONCLUSIONS: Even if no abnormalities are observed at the primary survey of elderly patients with severe trauma, physicians should consider the possibility of massive bleeding.


Asunto(s)
Transfusión Sanguínea/estadística & datos numéricos , Hemorragia/etiología , Hemorragia/terapia , Heridas y Lesiones/complicaciones , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Sistema de Registros , Estudios Retrospectivos , Resultado del Tratamiento
4.
Injury ; 46(9): 1779-83, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25943293

RESUMEN

INTRODUCTION: Acute coagulopathy of trauma has been much discussed recently. However, the changes in coagulation markers after trauma in the elderly are unknown. Furthermore, the baseline fibrinogen level is high in elderly patients, and the question remains as to whether fibrinogen levels also decrease early and the degree of decrease in elderly trauma patients. The purpose of this study was to compare coagulation markers including the fibrinogen level on admission in younger and elderly severe trauma patients. METHODS: A cohort of severe trauma patients (Injury Severity Score (ISS) ≥16), admitted from January 2011 to June 2014, with coagulation markers including the fibrinogen level on admission available, was reviewed retrospectively. The patients were divided into a younger (16-64 years old) and an older (≥65 years old) group based upon their age at presentation. Activated partial thromboplastin time (aPTT), international normalized ratio (INR), fibrinogen, and D-dimer were compared between the younger and older groups. RESULTS: There were 251 patients who met the inclusion criteria for this analysis. The younger group included 117 patients and the older group included 134 patients. The median aPTT (26.3 vs 27.5s, P=0.001) and median D-dimer levels (18.8 vs 40.2 µg/dL, P=0.006) were significantly higher in the older group. However, the fibrinogen level (205 vs 248 mg/dL, P<0.001) was significantly higher in the older group. The regression lines of fibrinogen and age in non-massive transfusion and massive transfusion cases are given by Y=1.03 X+185 (r=0.24, r(2)=0.06, P<0.001) and Y=0.86 X+134 (r=0.25, r(2)=0.06, P=0.09) respectively, and the fibrinogen levels tended to increase with older age in severe trauma patients. CONCLUSIONS: The fibrinogen level did not show a low value as it can in younger patients in elderly patients. Therefore, the fibrinogen level is difficult to use as an early indicator of acute blood loss with haemorrhage in elderly severe trauma patients, as it can be used in younger patients. Thus, it is necessary to keep in mind that the fibrinogen level increases by approximately 1mg/dL when the age increases by 1 year and to carefully observe the fibrinogen level even if the admission level is not low.


Asunto(s)
Afibrinogenemia/sangre , Hemorragia/sangre , Centros Traumatológicos/estadística & datos numéricos , Heridas y Lesiones/sangre , Adulto , Afibrinogenemia/etiología , Factores de Edad , Anciano , Femenino , Fibrinógeno , Hemorragia/etiología , Hemorragia/mortalidad , Humanos , Puntaje de Gravedad del Traumatismo , Japón/epidemiología , Modelos Lineales , Masculino , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Heridas y Lesiones/complicaciones , Heridas y Lesiones/mortalidad
5.
J Infect Chemother ; 20(1): 30-4, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24462421

RESUMEN

Presepsin is a protein whose levels increase specifically in the blood of patients with sepsis. It is proposed as a diagnostic and prognostic marker for assessing the degree of sepsis severity. The present multicenter prospective study compared the clinical utility of presepsin with other conventional sepsis biomarkers including procalcitonin, interleukin-6, and C-reactive protein for evaluating the severity of sepsis during follow-up. Patients with sepsis (n = 103) admitted to the emergency room or intensive care unit were enrolled in this study and classified into 3 diagnostic groups: sepsis, severe sepsis, and septic shock. Blood samples were obtained from each patient on admission and after 1, 3, 5, and 7 days. The patients were further divided into the favorable and unfavorable prognosis groups on the basis of several indicators of sepsis severity (i.e., Sequential Organ Failure Assessment score, and Acute Physiology and Chronic Health Evaluation II score). The patients in the favorable prognosis group exhibited significant decreases in all biomarker levels on days 3 and 7 after admission. In the unfavorable prognosis group, only presepsin levels did not decrease significantly during follow-up. The period of antibiotics treatment in the unfavorable prognosis group was significantly longer than those in the favorable prognosis group (P < 0.05). The unfavorable prognosis group had significantly higher 28-day mortality than the favorable prognosis group (P < 0.05). Therefore, the results suggest that presepsin levels correlated with the severity of sepsis during follow-up in comparison with other conventional sepsis biomarkers.


Asunto(s)
Receptores de Lipopolisacáridos/sangre , Sepsis/sangre , Anciano , Biomarcadores/sangre , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Pronóstico , Estudios Prospectivos
6.
J Infect Chemother ; 18(6): 891-7, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22692596

RESUMEN

The clinical usefulness of presepsin for discriminating between bacterial and nonbacterial infections (including systemic inflammatory response syndrome) was studied and compared with procalcitonin (PCT) and interleukin-6 (IL-6) in a multicenter prospective study. Suspected sepsis patients (n = 207) were enrolled into the study. Presepsin levels in patients with systemic bacterial infection and localized bacterial infection were significantly higher than in those with nonbacterial infections. In addition, presepsin, PCT, and IL-6 levels in patients with bacterial infectious disease were significantly higher than in those with nonbacterial infectious disease (P < 0.0001, P < 0.0001, and P < 0.0001, respectively). The area under the receiver operating characteristic curve was 0.908 for presepsin, 0.905 for PCT, and 0.825 for IL-6 in patients with bacterial infectious disease and those with nonbacterial infectious disease. The cutoff value of presepsin for discrimination of bacterial and nonbacterial infectious diseases was determined to be 600 pg/ml, of which the clinical sensitivity and specificity were 87.8 % and 81.4 %, respectively. Presepsin levels did not differ significantly between patients with gram-positive and gram-negative bacterial infections. The sensitivity of blood culture was 35.4 %; that for presepsin was 91.9 %. Also there were no significant differences in presepsin levels between the blood culture-positive and -negative groups. Consequently, presepsin is useful for the diagnosis of sepsis, and it is superior to conventional markers and blood culture.


Asunto(s)
Bacteriemia/sangre , Receptores de Lipopolisacáridos/sangre , Adulto , Anciano , Anciano de 80 o más Años , Bacteriemia/diagnóstico , Biomarcadores/sangre , Calcitonina/sangre , Péptido Relacionado con Gen de Calcitonina , Femenino , Humanos , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Precursores de Proteínas/sangre , Curva ROC , Sensibilidad y Especificidad , Estadísticas no Paramétricas
7.
J Hepatobiliary Pancreat Surg ; 15(2): 240-2, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18392724

RESUMEN

Xanthogranulomatous changes in the pancreas are extremely rare. A 66-year-old man presented with a 2-year history of epigastralgia. Computed tomography scan revealed a 4-cm low-density area around the body of the pancreas. Magnetic resonance imaging demonstrated that the mass appeared hyperintense on a T2-weighted image and isointense on a T1-weighted image. Based on a diagnosis of invasive ductal carcinoma of the pancreas, distal pancreatectomy and splenectomy were performed. Sections examined from the mass showed an aggregation of many foamy histiocytes, lymphocytes, and plasma cells. The surrounding pancreatic tissue showed fibrosis and chronic inflammation. These findings suggested a xanthogranulomatous inflammation, and resulted in a diagnosis of xanthogranulomatous pancreatitis.


Asunto(s)
Páncreas/patología , Pancreatitis/patología , Pancreatitis/cirugía , Anciano , Histiocitos/patología , Humanos , Linfocitos/patología , Masculino , Pancreatitis/diagnóstico , Células Plasmáticas/patología
8.
Diabetes ; 56(5): 1259-67, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17287463

RESUMEN

OBJECTIVE: Treatment of diabetic patients by pancreatic islet transplantation often requires the use of islets from two to four donors to produce insulin independence in a single recipient. Following isolation and transplantation, islets are susceptible to apoptosis, which limits their function and probably long-term islet graft survival. RESEARCH DESIGN AND METHODS: To address this issue, we examined the effect of the cell-permeable apoptosis inhibitor pentapeptide Val-Pro-Met-Leu-Lys, V5, on pancreatic islets in a mouse model. RESULTS: V5 treatment upregulated expression of anti-apoptotic proteins Bcl-2 and XIAP (X-linked inhibitor of apoptosis protein) by more than 3- and 11-fold and downregulated expression of apoptosis-inducing proteins Bax, Bad, and nuclear factor-kappaB-p65 by 10, 30, and nearly 50%, respectively. Treatment improved the recovered islet mass following collagenase digestion and isolation by 44% and in vitro glucose-responsive insulin secretion nearly fourfold. Following transplantation in streptozotocin-induced diabetic mice, 150 V5-treated islet equivalents functioned as well as 450 control untreated islet equivalents in normalizing blood glucose. CONCLUSIONS: These studies indicate that inhibition of apoptosis by V5 significantly improves islet function following isolation and improves islet graft function following transplantation. Use of this reagent in clinical islet transplantation could have a dramatic impact on the number of patients that might benefit from this therapy and could affect long-term graft survival.


Asunto(s)
Apoptosis/efectos de los fármacos , Insulina/metabolismo , Oligopéptidos/farmacología , Animales , Anexina A5/genética , Diabetes Mellitus Tipo 1/cirugía , Femenino , Regulación de la Expresión Génica , Secreción de Insulina , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Trasplante de Islotes Pancreáticos , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Animales , Oligopéptidos/síntesis química , Proteínas Proto-Oncogénicas c-bcl-2/genética , Donantes de Tejidos , Trasplante Isogénico , Proteína Inhibidora de la Apoptosis Ligada a X/genética
9.
Transplantation ; 83(2): 129-37, 2007 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-17264808

RESUMEN

BACKGROUND: Acute liver failure (ALF) is a serious condition that has a high mortality rate. Construction of an efficient culture and transplantation engineering system of hepatic tissue is an important approach to treat patients suffering from ALF to provide short-term hepatic support until the damaged liver spontaneously recovers or a donor liver becomes available for transplantation. Here, we evaluate the construction and transplantation of an engineered hepatic tissue (EHT) using primary isolated hepatocytes cultured onto polyaminourethane (PAU)-coated, nonwoven polytetrafluoroethylene (PTFE) fabric. METHODS: The isolated hepatocytes cultured onto PAU-coated PTFE fabric were able to adhere and spread over the individual fibers of the net and formed hepatic clusters after 3 days, such clusters revealed Gap junctions and well-developed bile canaliculi. RESULTS: When PAU-coated PTFE was utilized, ammonia-, and diazepam- metabolizing capacities and albumin production ability were significantly increased compared with collagen control. To test the function of this hepatic tissue in vivo, we transplanted a nonwoven PAU-coated PTFE fabric inoculated with one million hepatocytes on the surface of the spleen of Balb/c mice suffering from ALF induced by 90% hepatectomy, and found that this EHT prolonged the survival of liver failure-induced mice without adverse effects. Ultrastructure analyses showed good attachment of the cells on the surface of PTFE fabric and strong albumin expression seven days after the newly formed hepatic tissue was transplanted. CONCLUSION: We have here demonstrated the efficient construction and transplantation of hepatic tissue using primary hepatocytes and PAU-coated PTFE fabric.


Asunto(s)
Trasplante de Hígado/métodos , Hígado Artificial , Politetrafluoroetileno , Poliuretanos , Ingeniería de Tejidos/métodos , Albúminas/biosíntesis , Amoníaco/metabolismo , Animales , Supervivencia Celular , Diazepam/metabolismo , Hepatectomía , Humanos , Hígado/citología , Hígado/metabolismo , Hígado/cirugía , Ratones , Microscopía Electrónica de Transmisión , Tasa de Supervivencia , Porcinos
10.
Nat Biotechnol ; 24(11): 1412-9, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17086173

RESUMEN

Severe acute liver failure, even when transient, must be treated by transplantation and lifelong immune suppression. Treatment could be improved by bioartificial liver (BAL) support, but this approach is hindered by a shortage of human hepatocytes. To generate an alternative source of cells for BAL support, we differentiated mouse embryonic stem (ES) cells into hepatocytes by coculture with a combination of human liver nonparenchymal cell lines and fibroblast growth factor-2, human activin-A and hepatocyte growth factor. Functional hepatocytes were isolated using albumin promoter-based cell sorting. ES cell-derived hepatocytes expressed liver-specific genes, secreted albumin and metabolized ammonia, lidocaine and diazepam. Treatment of 90% hepatectomized mice with a subcutaneously implanted BAL seeded with ES cell-derived hepatocytes or primary hepatocytes improved liver function and prolonged survival, whereas treatment with a BAL seeded with control cells did not. After functioning in the BAL, ES cell-derived hepatocytes developed characteristics nearly identical to those of primary hepatocytes.


Asunto(s)
Diferenciación Celular/fisiología , Trasplante de Células/fisiología , Células Madre Embrionarias/fisiología , Células Madre Embrionarias/trasplante , Hepatocitos/fisiología , Fallo Hepático Agudo/terapia , Hígado Artificial , Activinas/fisiología , Animales , Técnicas de Cultivo de Célula/métodos , Trasplante de Células/métodos , Factor 2 de Crecimiento de Fibroblastos/fisiología , Factor de Crecimiento de Hepatocito/fisiología , Hepatocitos/citología , Humanos , Ratones , Modelos Animales
11.
Tissue Eng ; 12(7): 1799-809, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16889510

RESUMEN

Construction of a safe and functional bioartificial pancreas (BAP) that provides an adequate environment for islet cells may be an important approach to treating diabetic patients. Various types of BAP devices have been developed, but most of them involve extravascular implantation of islets in microcapsules or diffusion chambers. These devices have poor diffusive exchange between the islets and blood, and often rupture. To overcome these problems, we developed a new type of BAP composed of polyethylene-vinyl alcohol (EVAL) hollow fibers that are permeable to glucose and insulin and a poly-amino-urethane-coated, non-woven polytetrafluoroethylene (PTFE) fabric that allows cell adhesion. Porcine islets attached to the surface of the PTFE fabric, but not to the surface of the EVAL hollow fibers, allowing nutrient and oxygen exchange between blood flowing inside the fibers and cells outside. We inoculated this BAP with porcine islets and connected it to the circulation of totally pancreatectomized diabetic pigs. We found that blood glucose levels were reduced to a normal range and general health was improved, resulting in longer survival times. In addition, regulation of insulin secretion from the BAP was properly controlled in response to glucose both in vitro and in vivo. These results indicate that our newly developed BAP may be a potential therapy for the treatment of diabetes in humans.


Asunto(s)
Órganos Bioartificiales , Diabetes Mellitus Experimental/terapia , Membranas Artificiales , Páncreas Artificial , Animales , Glucemia/análisis , Diabetes Mellitus Experimental/sangre , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/metabolismo , Ratones , Porcinos
12.
Cell Transplant ; 15(4): 325-34, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16898226

RESUMEN

Development of an efficient preculture system of islets is ideal. Toward that goal, we constructed a human pancreatic islet-derived fibroblast cell line MNNK-1 for a source as a coculture system for freshly isolated islets to maintain islet functions. Human pancreatic islet cells were nucleofected with a plasmid vector pYK-1 expressing simian virus 40 large T antigen gene (SV40T) and hygromycin resistance gene (HygroR). One of the transduced cell lines, MNNK-1, was established and served as a feeder cell in the coculture for freshly isolated mouse, rat, and pig islets. Morphology, viability, and glucose-responding insulin secretion were analyzed in the coculture system. MNNK-1 cells were morphologically spindle shaped and were negative for pancreatic endocrine markers. MNNK-1 cells were positive for alpha-smooth muscle actin and collagen type I and produced fibroblast growth factor. Coculture of the mouse, rat, and pig islets with MNNK-1 cells maintained their viability and insulin secretion with glucose responsiveness. A human pancreatic islet-derived fibroblast cell line MNNK-1 was established. MNNK-1 cells were a useful means for maintaining morphology and insulin secretion of islets in the coculture system.


Asunto(s)
Fibroblastos/citología , Islotes Pancreáticos/fisiología , Actinas/metabolismo , Animales , Línea Celular Transformada , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Técnicas de Cocultivo/métodos , Colágeno Tipo I/metabolismo , Fibroblastos/metabolismo , Fibroblastos/fisiología , Ganciclovir/farmacología , Glucosa/metabolismo , Humanos , Insulina/metabolismo , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Ratones , Ratones SCID , Ratas , Porcinos , Supervivencia Tisular/fisiología
13.
Transplantation ; 81(3): 427-37, 2006 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-16477231

RESUMEN

BACKGROUND: Because hepatocyte transplantation has been considered to be an attractive method to treat acute liver failure (ALF), efficient recovery of hepatocytes and maintenance of differentiated hepatocyte functions is of extreme importance. We here report the usefulness of an antiapoptotic pentapeptide V5, composed of Val-Pro-Met-Leu-Lys, in the monkey hepatocyte cultures. METHODS: We evaluated albumin production, metabolizing abilities of ammonia, lidocaine, and diazepam of monkey hepatocytes cultured with V5. The protein expression of apoptosis-associated molecules was analyzed using power blot analysis. An unwoven cloth inoculated with V5-treated monkey hepatocytes was transplanted on the surface of the spleen of both SCID mice and Balb/c mice suffering from ALF induced by 90% hepatectomy. RESULTS: When 100 microM V5 was utilized, ammonia-, lidocaine- and diazepam- metabolizing capacities and albumin production ability were significantly increased in V5-treated monkey hepatocytes. Such hepatocytes showed decreased Annexin V binding and increased the expression of anti-apoptotic and/or cytoprotective molecules, including Ku70, NF-kappaB, IKAP, hILP/XIAP, IkappaB, and CAS. Transplantation of the cloth containing the monkey hepatocytes significantly improved blood levels of glucose and ammonia and encephalopathy score and prolonged the survival of the mice with ALF. CONCLUSIONS: The present work clearly demonstrates the usefulness of V5 for maintaining the functions of monkey hepatocytes in tissue culture.


Asunto(s)
Hepatocitos/trasplante , Fallo Hepático Agudo/cirugía , Oligopéptidos/farmacología , Trasplante Heterólogo , Amoníaco/metabolismo , Animales , Técnicas de Cultivo de Célula , Células Cultivadas , Diazepam/metabolismo , Haplorrinos , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Lidocaína/metabolismo , Hígado/citología , Regeneración Hepática , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Mitocondrias Hepáticas/ultraestructura , Albúmina Sérica/biosíntesis , Albúmina Sérica/genética , Bazo/citología , Bazo/cirugía , Análisis de Supervivencia , Resultado del Tratamiento
14.
Cell Transplant ; 15(4): 325-334, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28863744

RESUMEN

Development of an efficient preculture system of islets is ideal. Toward that goal, we constructed a human pancreatic islet-derived fibroblast cell line MNNK-1 for a source as a coculture system for freshly isolated islets to maintain islet functions. Human pancreatic islet cells were nucleofected with a plasmid vector pYK-1 expressing simian virus 40 large T antigen gene (SV40T) and hygromycin resistance gene (HygroR). One of the transduced cell lines, MNNK-1, was established and served as a feeder cell in the coculture for freshly isolated mouse, rat, and pig islets. Morphology, viability, and glucose-responding insulin secretion were analyzed in the coculture system. MNNK-1 cells were morphologically spindle shaped and were negative for pancreatic endocrine markers. MNNK-1 cells were positive for α-smooth muscle actin and collagen type I and produced fibroblast growth factor. Coculture of the mouse, rat, and pig islets with MNNK-1 cells maintained their viability and insulin secretion with glucose responsiveness. A human pancreatic islet-derived fibroblast cell line MNNK-1 was established. MNNK-1 cells were a useful means for maintaining morphology and insulin secretion of islets in the coculture system.

15.
Cell Transplant ; 15(10): 855-64, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17299989

RESUMEN

Since Berry and Friend developed methods to isolate hepatocytes from the liver by a collagenase digestion technique in 1969, studies in laboratory animals have demonstrated that hepatocyte transplantation could potentially be used for the treatment of liver failure and inborn errors of liver-based metabolism. Healthy human hepatocytes are an ideal source for hepatocyte transplantation; however, their relative scarcity is one of the major drawbacks, further compounded by the competing demands of liver transplantation. Notably, most of the hepatocytes are isolated from discarded livers that are not suitable for organ transplantation for a variety of reasons, including excessive fat content. Importantly, the hepatocyte isolation procedure itself exerts major stress on hepatocytes by the disruption of cell-to-cell and cell-to-matrix contacts, resulting in hepatocytic apoptosis. Prevention of apoptosis would maximize yield of healthy cells and maintain hepatocyte differentiated function in culture. In this review, we describe methods to prevent apoptosis by utilizing both antiapoptotic molecules and matrices. We also introduce a new type of liver tissue engineering, hepatocyte sheet transplantation, which utilizes unwoven cloth having a cellular adhesive property.


Asunto(s)
Trasplante de Células/métodos , Hepatocitos/trasplante , Apoptosis , Hepatocitos/citología , Humanos , Hígado/citología , Hígado/metabolismo , Modelos Biológicos , Ingeniería de Tejidos/métodos
16.
Cell Transplant ; 15(10): 893-901, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17299994

RESUMEN

Development of a subcutaneously implantable bioartificial pancreas (BAP) with immunoisolatory function could have a great impact on the treatment of diabetes mellitus. We have developed an implantable BAP device with an ethylene vinyl alcohol (EVAL) membrane. In the present study, we used basic fibroblast growth factors (bFGF), which was incorporated in a carrier for sustained release, in order to induce neovascularization when the device was implanted subcutaneously. To maintain the vasculature thus formed, a cell infusion port was attached to the BAP device, through which the device was filled with human liver vascular endothelial cell line TMNK-1, and the vasculature could be adequately maintained. Mice were divided into the following three groups. In group 1, a bFGF-free BAP device was implanted subcutaneously. In group 2, a sustained-release bFGF-impregnated BAP device was implanted. In group 3, a sustained-release bFGF-impregnated BAP device was implanted, and 3 x 10(6) TMNK-1 cells were infused into the implanted device every week. Neovascularization induced in the subcutaneous tissue around the implanted BAP device was macroscopically examined and histologically evaluated. In addition, the tissue blood flow was measured using a laser blood flow meter. In mice in group 3, neovascularization was significantly induced and maintained until week 8 postimplantation. It was confirmed by scanning electron microscopy that infused TMNK-1 cells adhered to the inner polyethylene surface of the device. It was demonstrated that the use of bFGF and vascular endothelial TMNK-1 cells induced and maintained adequate vasculature and tissue blood flow surrounding the implantable bag-type BAP device. We believe that the present study will contribute to BAP development for the treatment of diabetes.


Asunto(s)
Trasplante de Células/métodos , Células Endoteliales/citología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Páncreas Artificial , Animales , Vasos Sanguíneos/ultraestructura , Adhesión Celular , Línea Celular , Células Endoteliales/trasplante , Células Endoteliales/ultraestructura , Humanos , Inmunohistoquímica , Hígado/citología , Masculino , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica de Rastreo , Trasplante Heterólogo
17.
Cell Transplant ; 15(10): 903-10, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17299995

RESUMEN

Artificial bones have often used for bone regeneration due to their strength, but they cannot provide an adequate environment for cell penetration and settlement. We therefore attempted to explore various materials that may allow the cells to penetrate and engraft in bone defects. PuraMatrix is a self-assembling peptide scaffold that produces a nanoscale environment allowing both cellular penetration and engraftment. The objective of this study was to investigate the effect of PuraMatrix on bone regeneration in a mouse bone defect model of the calvaria. Matrigel was used as a control. The expression of bone-related genes (alkaline phosphatase, Runx2, and Osterix) in the PuraMatrix-injected bone defects was stronger than that in the Matrigel-injected defects. Soft X-ray radiographs revealed that bony bridges were clearly observed in the defects treated with PuraMatrix, but not in the Matrigel-treated defects. Notably, PuraMatrix treatment induced mature bone tissue while showing cortical bone medullary cavities. The area of newly formed bones at the site of the bone defects was 1.38-fold larger for PuraMatrix than Matrigel. The strength of the regenerated bone was 1.72-fold higher for PuraMatrix (146.0 g) than for Matrigel (84.7 g). The present study demonstrated that PuraMatrix injection favorably induced functional bone regeneration.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Sustitutos de Huesos/uso terapéutico , Trasplante Óseo/métodos , Cráneo/cirugía , Fosfatasa Alcalina/genética , Animales , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Femenino , Expresión Génica/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones SCID , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Cráneo/metabolismo , Cráneo/fisiopatología , Factor de Transcripción Sp7 , Factores de Transcripción/genética
18.
Nat Biotechnol ; 23(10): 1274-82, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16186810

RESUMEN

A human pancreatic beta-cell line that is functionally equivalent to primary beta-cells has not been available. We established a reversibly immortalized human beta-cell clone (NAKT-15) by transfection of primary human beta-cells with a retroviral vector containing simian virus 40 large T-antigen (SV40T) and human telomerase reverse transcriptase (hTERT) cDNAs flanked by paired loxP recombination targets, which allow deletion of SV40T and TERT by Cre recombinase. Reverted NAKT-15 cells expressed beta-cell transcription factors (Isl-1, Pax 6, Nkx 6.1, Pdx-1), prohormone convertases 1/3 and 2, and secretory granule proteins, and secreted insulin in response to glucose, similar to normal human islets. Transplantation of NAKT-15 cells into streptozotocin-induced diabetic severe combined immunodeficiency mice resulted in perfect control of blood glucose within 2 weeks; mice remained normoglycemic for longer than 30 weeks. The establishment of this cell line is one step toward a potential cure of diabetes by transplantation.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Diabetes Mellitus Tipo 1/cirugía , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/fisiología , Ingeniería de Tejidos/métodos , Animales , Línea Celular , Proliferación Celular , Mejoramiento Genético/métodos , Humanos , Ratones , Ratones SCID , Resultado del Tratamiento
19.
Transplantation ; 79(10): 1378-85, 2005 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-15912107

RESUMEN

BACKGROUND: Considering the scarcity of donor livers, it is extremely important to establish a functional culture method for isolated hepatocytes. As a tool for maintaining hepatocyte functions in vitro, dHGF, a variant of HGF (hepatocyte growth factor) with a deletion of five amino acids, attracted our attention because it is less cytotoxic compared with HGF. METHODS: We evaluated growth, albumin production, metabolizing abilities of ammonia, lidocaine, and diazepam of human hepatocytes in the presence of dHGF (10-1000 ng/ml). The gene expression of liver markers was comparatively analyzed. The effect of intrasplenic transplantation of dHGF-treated human hepatocytes into severe combined immunodeficient (SCID) mice was evaluated in an acute liver failure (ALF) model induced by D-galactosamine (D-gal). RESULTS: When 100 ng/ml of dHGF was utilized, metabolism rates of ammonia, lidocaine, and diazepam and albumin production per unit cell significantly increased. The gene expression analysis demonstrated the enhanced expression of albumin, HNF-4alpha, and C/EBPalpha in the hepatocytes treated with 100 ng/ml of dHGF. Transplantation of such hepatocytes prolonged the survival of the SCID mice with ALF induced by D-gal. CONCLUSIONS: The present work clearly demonstrates the usefulness of dHGF (100 ng/ml) for maintaining the differentiated functions of human hepatocytes in tissue culture.


Asunto(s)
Eliminación de Gen , Factor de Crecimiento de Hepatocito/genética , Factor de Crecimiento de Hepatocito/farmacología , Hepatocitos/trasplante , Fallo Hepático Agudo/cirugía , Hígado/cirugía , Trasplante Heterólogo , Albúminas/genética , Albúminas/metabolismo , Amoníaco/metabolismo , Animales , Proteína alfa Potenciadora de Unión a CCAAT/genética , División Celular/efectos de los fármacos , Niño , Proteínas de Unión al ADN/genética , Diazepam/metabolismo , Femenino , Expresión Génica/efectos de los fármacos , Variación Genética , Factor Nuclear 4 del Hepatocito , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Lidocaína/metabolismo , Hígado/patología , Fallo Hepático Agudo/fisiopatología , Masculino , Ratones , Ratones SCID , Persona de Mediana Edad , Fosfoproteínas/genética , Análisis de Supervivencia , Técnicas de Cultivo de Tejidos , Factores de Transcripción/genética
20.
ASAIO J ; 50(6): 586-90, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15672793

RESUMEN

Expansion of pancreatic islet cell populations, especially the beta cells, using a currently available ex vivo gene transfer technology is important to develop cell therapies to treat Type I diabetes. In this study, we evaluated adenovirus mediated gene transfer efficiency in primarily isolated mouse islet cells in two types of culture conditions: freshly isolated suspended islets and cultured islets with monolayer formation. A recombinant replication deficient adenovirus vector encoding a green fluorescence protein (GFP) cDNA, Ad/ CMV-GFP, was used in the present transduction experiments. Rat 804G derived extracellular matrix (804G-ECM) and 3-isobutyl-1-methylxanthine (IBMX) were used to facilitate monolayer formation of the isolated mouse pancreatic islets. Suspended islets were transfected with Ad/CMV-GFP at more than 95% efficiency. However, analysis of immunohistochemical stains for insulin and glucagon in thin sliced sections of the islets revealed that GFP expression was localized just in the outer cells of the islets, almost all of which were glucagon positive alpha-cells. The beta-cells existing at the inner area of the suspended islets were GFP negative. In contrast, under the condition of the islets in monolayer formation cultures, all of the islet cells including the beta-cells were efficiently infected with Ad/CMV-GFP. To achieve an efficient adenoviral gene transfer to the pancreatic beta-cells, monolayer formation of the islets is critical. Such culture conditions were facilitated by combining 804G-ECM with IBMX.


Asunto(s)
Adenoviridae/genética , Vectores Genéticos , Islotes Pancreáticos , Transducción Genética , 1-Metil-3-Isobutilxantina/farmacología , Animales , Adhesión Celular , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Citomegalovirus/genética , Matriz Extracelular , Glucagón/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Técnicas Histológicas , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/citología , Islotes Pancreáticos/fisiología , Trasplante de Islotes Pancreáticos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones SCID , Ratas , Distribución Tisular , Transducción Genética/métodos
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