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2.
Gut ; 51(4): 579-84, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12235084

RESUMEN

BACKGROUND: Pancreatic stellate cells (PSCs) have been implicated in pancreatic fibrosis as they synthesise increased amounts of extracellular matrix proteins in response to activation by profibrogenic mediators such as cytokines. AIMS: The purpose of this study was to analyse cytokine receptor stimulated signalling pathways involved in PSC activation. Using a rat culture model of PSCs, we have also tested the potential of the platelet derived growth factor (PDGF) antagonist trapidil and PD98059, a specific inhibitor of extracellular signal regulated kinase (ERK) activation, to suppress PSC growth. METHODS: Cultured PSCs were stimulated with PDGF, and the signal transduction pathways activated in response to the mitogen were analysed by immunoblotting, kinase assays, and electrophoretic mobility shift assays. Furthermore, comparison of signalling cascades activated in PSCs before and after completing transdifferentiation to alpha-smooth muscle actin expressing myofibroblasts was performed. Biological effects of PDGF, trapidil, and PD98059 were analysed by proliferation assays and correlated with molecular effects of the substances. RESULTS: PDGF induced rapid activation of Raf-1, ERKs 1 and 2, as well as AP-1 proteins. The transforming growth factor beta activated transcription factor Smad2 was found to be constitutively phosphorylated in PSCs of different transdifferentiation grades. Furthermore, the results indicate a correlation between ERK activities and induction of PSC activation. Trapidil efficiently inhibited both PDGF induced ERK activation and, in common with PD98059, PSC proliferation. CONCLUSIONS: Our data suggest that ERKs play a key role in the regulation of PSC growth and that inhibition of the ERK signalling pathway may become a strategy to prevent activation of these cells.


Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Páncreas/efectos de los fármacos , Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Transducción de Señal , Trapidil/farmacología , Animales , División Celular/efectos de los fármacos , Ensayo de Cambio de Movilidad Electroforética , Ensayo de Inmunoadsorción Enzimática , Immunoblotting , Masculino , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Páncreas/citología , Páncreas/enzimología , Proteínas Proto-Oncogénicas c-raf/metabolismo , Ratas , Ratas Endogámicas Lew , Factor de Transcripción AP-1/metabolismo
3.
Chirurg ; 73(5): 466-73, 2002 May.
Artículo en Alemán | MEDLINE | ID: mdl-12089831

RESUMEN

INTRODUCTION: Complications after pancreatic resections remain frequent despite a decreasing mortality. Pancreatic leakages represent a relevant part of those complications but data on risk factors for their occurrence are rare. We analyzed our experience with incidence, clinical course, and risk factors of pancreatic leakage in a large patient group. METHODS: We analyzed the prospectively documented perioperative data of 345 patients with pancreatic resections carried out between 1994 and 2001. Main indications for surgery were chronic pancreatitis (57%) and malignant tumors (37%). The following operations were performed: Whipple's operation 15%, pylorus-preserving pancreaticoduodenectomy 53%, duodenum-preserving pancreatic head resection 19%, and distal pancreatic resection 13%. Risk factors were analyzed using uni- and multivariate methods. RESULTS: Postoperative mortality and complication rate were 2.9% and 41%, respectively. A pancreatic leakage occurred in 9.9%. In the majority of patients, pancreatic leakage was asymptomatic and controlled by prolonged drainage. However, one fourth of the patients with pancreatic leakage required reoperation. The mortality of pancreatic leakage was 12%. No patient with chronic pancreatitis died as a consequence of pancreatic leakage. Impaired preoperative renal function was the only risk factor for the occurrence of postoperative pancreatic leakage. CONCLUSIONS: Although easily managed in the majority of cases, pancreatic leakage still represents a relevant postoperative complication after pancreatic resection, especially in patients with malignant disease. Because of an increased risk of developing pancreatic leakage, an impaired renal function should be considered specifically in the perioperative management of the patients.


Asunto(s)
Neoplasias del Conducto Colédoco/cirugía , Pancreatectomía , Fístula Pancreática/etiología , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía , Pancreatitis/cirugía , Complicaciones Posoperatorias/etiología , Adolescente , Adulto , Anciano , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fístula Pancreática/cirugía , Complicaciones Posoperatorias/cirugía , Reoperación , Estudios Retrospectivos , Factores de Riesgo
4.
Dtsch Med Wochenschr ; 127(16): 845-9, 2002 Apr 19.
Artículo en Alemán | MEDLINE | ID: mdl-11961701

RESUMEN

HISTORY: A 35-year-old male was admitted with recurrent acute pancreatitis of unknown origin. He was found to have a cystic lesion in the upper abdomen believed to be a pancreatic pseudocyst (patient 1). A 59-year-old female with a choledochal cyst developed acute pancreatitis (patient 2). A 32-year-old male who had been operated upon for a choledochal cyst during childhood was admitted for upper abdominal pain, fever and vomitus (patient 3). INVESTIGATIONS AND DIAGNOSIS: Patient 1 was found to have a choledochal cyst type IV a according to TODANI. Patient 2 was diagnosed to have a choledochal cyst type Ib according to TODANI. The cyst was believed to contain a bile duct carcinoma. In patient 3, sonography showed an advanced Klatskin tumour with infiltration of the portal vein, the hepatic artery and the liver. Bile cytology confirmed the carcinoma. In all patients cholestasis was found. Pancreatic enzymes were elevated in patients 2 and 3. TREATMENT AND COURSE: Patient 1 underwent left hemihepatectomy and received a biliodigestive anastomosis. In patient 2 the choledochal cyst was resected while undergoing pylorus-preserving resection of the pancreatic head. The tumour suspected was confirmed and R0 resected. Patient 3 presented with an incurable bile duct carcinoma. He died 3 months later from multiple lung emboli. CONCLUSION: Choledochal cysts are associated with a 20 fold increase in the incidence of bile duct carcinoma.


Asunto(s)
Neoplasias de los Conductos Biliares/etiología , Colangiocarcinoma/etiología , Quiste del Colédoco/complicaciones , Pancreatitis/etiología , Enfermedad Aguda , Adulto , Neoplasias de los Conductos Biliares/diagnóstico , Neoplasias de los Conductos Biliares/cirugía , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/cirugía , Quiste del Colédoco/diagnóstico , Resultado Fatal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Resultado del Tratamiento
5.
Virchows Arch ; 438(6): 581-90, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11469690

RESUMEN

Mutation of the K-ras gene is thought to be an early and important event in pancreatic carcinogenesis. In order to study the role of this molecular alteration in the transition from the normal to the neoplastic pancreatic cell, bovine pancreatic duct cells were first immortalized by SV40 large T antigen (Ag) complementary (c)DNA transfection and then transfected with a mutated K-ras gene. As did primary duct cells, the immortalized duct cells (more than 100 passages) expressed cytokeratins, carbonic anhydrase type-II, cystic fibrosis transmembrane conductance regulator (CFTR), and multidrug resistance (mdr). They grew as a single layer after transplantation under plastic domes and formed three-dimensional structures resembling ducts when grown on Matrigel. Cell growth was stimulated by insulin, epidermal growth factor (EGF), transforming growth factor (TGF)-alpha, but cells did not respond to gastrin and CCK-8. They did not form colonies in soft agar nor did they form tumors in nude mice. Immortalized cells transfected with mutated K-ras acquired the ability to form tumors after orthotopic injection into the nude mouse pancreas. It is concluded that SV 40 immortalized bovine pancreatic


Asunto(s)
Transformación Celular Neoplásica/patología , Genes ras/genética , Mutación , Conductos Pancreáticos/patología , Neoplasias Pancreáticas/patología , Transfección/métodos , Animales , Antígenos Transformadores de Poliomavirus/genética , Biomarcadores/análisis , Bovinos , División Celular/efectos de los fármacos , Línea Celular Transformada , Transformación Celular Neoplásica/química , Transformación Celular Neoplásica/genética , Células Clonales , ADN Complementario/genética , Factor de Crecimiento Epidérmico/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Técnica del Anticuerpo Fluorescente Indirecta , Insulina/farmacología , Ratones , Ratones Desnudos , Conductos Pancreáticos/efectos de los fármacos , Conductos Pancreáticos/metabolismo , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/genética , Reacción en Cadena de la Polimerasa , ARN Viral/biosíntesis , Factor de Crecimiento Transformador alfa/farmacología
6.
Lancet ; 357(9268): 1591-2, 2001 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-11377651

RESUMEN

Pancreatic cancer can seldom be resected, and chemotherapy has only a limited effect on survival or tumour load. We did a phase I/II trial in 14 patients with pancreatic cancer to assess the safety of local activation of low-dose ifosfamide. We encapsulated genetically modified allogeneic cells, which expressed a cytochrome P450 enzyme, in cellulose sulphate and delivered them by supraselective angiography to the tumour vasculature. These cells locally activated systemically administered ifosfamide. The tumours of four patients regressed after treatment, and those of the other ten individuals who completed the study remained stable. Median survival was doubled in the treatment group by comparison with historic controls, and 1-year survival rate was three times better. Further studies of this cell-therapy-based treatment combined with chemotherapy for inoperable pancreatic cancer are warranted.


Asunto(s)
Adenocarcinoma/terapia , Trasplante de Células/métodos , Citocromo P-450 CYP2B1/metabolismo , Ifosfamida/administración & dosificación , Cuidados Paliativos/métodos , Neoplasias Pancreáticas/terapia , Adenocarcinoma/diagnóstico , Adenocarcinoma/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Composición de Medicamentos , Sistemas de Liberación de Medicamentos/métodos , Femenino , Estudios de Seguimiento , Terapia Genética/métodos , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/mortalidad , Tasa de Supervivencia , Enfermo Terminal , Transfección , Trasplante Homólogo , Resultado del Tratamiento
7.
Gastrointest Endosc ; 53(7): 734-43, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11375580

RESUMEN

BACKGROUND: Mutations in p53 and ras genes are frequent in pancreatic carcinoma. Several ras mutations are consistently detected in the pancreatic juice from patients with chronic pancreatitis. The p53 gene mutations have been detected occasionally in chronic pancreatitis tissue. It was the aim of this study to evaluate the presence and clinical significance of p53 and ras mutations in clinical pancreatic juice samples from patients with chronic pancreatitis. METHODS: Pancreatic juice was obtained from 66 patients with chronic pancreatitis and no evidence of pancreatic carcinoma (51 men, 15 women; age 17-86 years [mean 49.6 +/- 12.9]). Patients were followed prospectively for 26 +/- 3 (4-54) months. Detection of p53 gene mutations was by temperature gradient gel electrophoresis (TGGE) and single strand conformation polymorphism (SSCP) for exons 5-8. Analysis of ras mutations was performed by SSCP/polymerase chain reaction, restriction fragment length polymorphism/polymerase chain reaction. All mutations were confirmed by sequencing. RESULTS: Five of 66 (7.5%) pancreatic juice samples contained p53 mutations, and ras mutations were detected in 6 cases (9%). Cytology was negative in all cases. No pancreatic carcinoma developed during follow-up and neither cancer cells nor preneoplastic lesions could be detected histologically in resected specimens. Although no correlation between p53 mutations and duration of pancreatitis or drinking habits was found, K-ras mutations correlated with both heavy smoking and severity of the disease. CONCLUSION: p53 and ras mutations can be detected in a minority of pancreatic juice samples from patients with chronic pancreatitis in the absence of malignancy.


Asunto(s)
Genes p53/genética , Genes ras/genética , Mutación , Jugo Pancreático/metabolismo , Pancreatitis/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , Distribución de Chi-Cuadrado , Enfermedad Crónica , Femenino , Marcadores Genéticos , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Pancreatitis/diagnóstico , Reacción en Cadena de la Polimerasa , Probabilidad , Estudios Prospectivos , Sensibilidad y Especificidad , Estadísticas no Paramétricas
8.
Z Gastroenterol ; 39(2): 177-80, 2001 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-11253510

RESUMEN

Anisakiasis or "herring worm disease" is one of the most important parasitic diseases of the gastrointestinal tract in Japan. In 1988 Lorenz and Warzok published 8 cases of intestinal anisakiasis in Eastern Germany. In 1988 Spehn et al. reported a case of gastric anisakiasis in an AIDS patient. Here, we describe a case of gastric anisakiasis in Germany with an impressive serious clinical course. The symptoms--acute abdominal cramps, severe chest pain, diarrhoea, sub-febrile temperatures and leucocytosis--followed 4 h after consumption of raw herring, which was homemade pickled in vinegar. The conventional and the endoscopic ultrasonography showed a thickened gastric wall made of mainly thickened submucosa. The larvae of Anisakis in the gastric mucosa were found and extracted endoscopically. Acute and severe abdominal pain after eating raw fish is an indication for early gastroscopy. The endoscopical extraction of possible larvae is the only effective therapy, as anthelmintics against nematodes (mebendazole, albendazole, thiabendazole) are ineffective.


Asunto(s)
Anisakiasis/diagnóstico , Gastropatías/diagnóstico , Animales , Anisakiasis/patología , Anisakiasis/transmisión , Diagnóstico Diferencial , Femenino , Peces/parasitología , Parasitología de Alimentos , Mucosa Gástrica/parasitología , Mucosa Gástrica/patología , Gastroscopía , Humanos , Persona de Mediana Edad , Gastropatías/patología
9.
Eur J Clin Invest ; 31(3): 240-7, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11264652

RESUMEN

The diagnosis of biliary disease, namely malignant disorders, is frequently hampered by the inconclusive cytology. We investigated prospectively the frequency of molecular changes in p53 and ras compared with cytology in patients with primary or secondary hepato-biliary disease. We investigated 118 consecutive patients, aged 24-89 with the following clinical diagnoses: choledocho/cholecystolithiasis (28), cholangiocellular carcinoma (21), gall bladder tumor (8), liver metastasis (3), autoimmune disease (8), chronic pancreatitis (16), pancreatic carcinoma (11), papillary disease (4), hepatic cirrhosis (6), cholangitis (2), anomalies (2), and normal (9). Bile was aspirated during routine endoscopic retrograde cholangio pancreatography (ERCP) or percutaneous transhepatic cholangiography (PTC). DNA was prepared freshly from a native aliquot. p53 mutations were detected by polymerase chain reaction (PCR) for exons 5 through 8 followed by TGGE. PCR for ras mutations was performed as RFLP-PCR with sequencing. In four cases, mutations in p53 could be found in exons 6 and 7. Twenty-two samples showed ras mutations; ras mutations were found in choledocholithiasis (4/28), bile duct (5/21), gall bladder (3/8) and pancreatic (1/11) carcinoma, liver metastasis (3/3), ulcerative colitis (2/3), PSC (1/2), and chronic pancreatitis (1/16). Cytology was clearly positive in seven cases, suspicious in three other, inconclusive in six, and negative in the rest. The molecular analysis resulted in a sensitivity of 33% and specificity of 87%, respectively, for the diagnosis of a malignant condition. PCR for p53 and ras mutations may aid the diagnosis of primary and secondary (metastatic) hepatobiliary disease if a malignant condition of the bile ducts and the liver is suspected and cytology is inconclusive or negative. However, the incidence of p53 and ras mutations in bile seems less frequent than in other malignant conditions of the gastrointestinal tract and the pancreas and lower than in tissue, leaving a poor sensitivity and specificity. Nevertheless, the presence of a p53 and/or ras mutation per se supports a clinical suspicion of malignancy, even when the conventional cytology is negative or inconclusive.


Asunto(s)
Bilis/metabolismo , Enfermedades de las Vías Biliares/genética , Genes p53/genética , Genes ras/genética , Hepatopatías/genética , Mutación/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de los Conductos Biliares/química , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/patología , Enfermedades de las Vías Biliares/metabolismo , Enfermedades de las Vías Biliares/patología , Colangiocarcinoma/química , Colangiocarcinoma/genética , Colangiocarcinoma/patología , Colelitiasis/química , Colelitiasis/genética , Colelitiasis/patología , Femenino , Humanos , Inmunohistoquímica , Hepatopatías/metabolismo , Hepatopatías/patología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Estudios Prospectivos
10.
Med Klin (Munich) ; 94(6): 345-52, 1999 Jun 15.
Artículo en Alemán | MEDLINE | ID: mdl-10420727

RESUMEN

CASE REPORT: We describe the case of a 43-year-old patient with a Burkitt lymphoma in the small intestine, who initially presented with abdominal discomfort, weight loss, constipation and neurological symptoms. DIAGNOSIS: In terms of differential diagnosis other inflammatory and tumorous diseases had to be considered. Non-Hodgkin lymphomas are common malignant afflictions of the GI-tract. The total body tumor burden is the principal determinant of prognosis. Serum lactate dehydrogenase (LDH) level is one parameter that reflects the tumor burden. On the other hand abdominal mass, bone marrow and central nervous system involvement are negative prognostic factors. Lymphomas can invade in the CNS at any time during the course of disease. This is generally associated with a poor prognosis if not treated immediately. TREATMENT: High doses of cyclophosphamid and MTX have been shown successful in the treatment of Burkitt lymphoma. Almost all relapses occur on therapy or shortly after termination of treatment. Therefore, criteria are needed to select patients of higher and lesser risk to protect the latter from the further intensification of therapy.


Asunto(s)
Linfoma de Burkitt/diagnóstico , Neoplasias del Yeyuno/diagnóstico , Linfoma Relacionado con SIDA/diagnóstico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma de Burkitt/tratamiento farmacológico , Linfoma de Burkitt/patología , Linfoma de Burkitt/cirugía , Quimioterapia Adyuvante , Terapia Combinada , Diagnóstico Diferencial , Humanos , Neoplasias del Yeyuno/tratamiento farmacológico , Neoplasias del Yeyuno/patología , Neoplasias del Yeyuno/cirugía , Yeyuno/patología , Yeyuno/cirugía , Linfoma Relacionado con SIDA/tratamiento farmacológico , Linfoma Relacionado con SIDA/patología , Linfoma Relacionado con SIDA/cirugía , Masculino , Estadificación de Neoplasias
11.
Ann N Y Acad Sci ; 880: 50-65, 1999 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-10415850

RESUMEN

Although pancreatic adenocarcinoma has become one of the best characterized malignant diseases, severe diagnostic and therapeutic problems are still associated with this disease. The establishment of a molecular model of pancreatic carcinogenesis may provide tools that could result in earlier diagnosis of this disease and, in turn, improves prognosis. Since pancreatic adenocarcinoma seems to originate in epithelial cells in the pancreatic ducts, cultivation of native pancreatic duct epithelial cells (PDEC) is the initial step in the establishment of an in vitro model of pancreatic carcinogenesis. As these native cells survive only a short period in culture, the aim of this study was to establish a stable pancreatic duct cell line by immortalization with the SV40 large T antigen. Furthermore, initial steps in pancreatic carcinogenesis should possibly be imitated by additional transfections of mutated ki-ras and/or mutated p53 genes. By optimization of the isolation protocol and the culture medium, yield as well as proliferative activity of isolated PDEC was increased considerably. Transfection of SV40 large T antigen resulted in an increase in the proliferative lifetime of the isolated cells, but no real immortal phenotype was obtained. Moreover, one step in the transformation from the normal to the malignant phenotype was imitated successfully by additional transfection of mutated ki-ras.


Asunto(s)
Línea Celular Transformada , Conductos Pancreáticos/citología , Animales , Antígenos Transformadores de Poliomavirus/genética , Bovinos , Línea Celular , Transformación Celular Neoplásica , Células Epiteliales/citología , Células Epiteliales/metabolismo , Humanos , Ratones , Ratones Desnudos , Neoplasias Pancreáticas/patología , Células Tumorales Cultivadas
16.
Ann N Y Acad Sci ; 880: 337-51, 1999 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-10415878

RESUMEN

The prognosis of pancreatic cancer is poor, and current medical treatment is mostly ineffective. The aim of this study was to design a new treatment modality in an animal model system. We describe here a novel treatment strategy employing a mouse model system for pancreatic carcinoma. Embryonal kidney epithelial cells were genetically modified to express the cytochrome P450 subenzyme 2B1 under the control of a cytomegalovirus (CMV) immediate early promoter. This CYP2B1 gene converts ifosfamide to its active cytotoxic compounds, phosphoramide mustard, which alkylates DNA, and acrolein, which alkylates proteins. The cells were then encapsulated in a cellulose sulphate formulation and implanted into preestablished tumors derived from a human pancreatic tumor cell line. Intraperitoneal administration of low-dose ifosfamide to tumor bearing mice that received the encapsulated cells results in partial or even complete tumor ablation. Such an in situ chemotherapy strategy utilizing genetically modified cells in an immunoprotected environment may prove useful for solid tumor therapy in man.


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Citocromo P-450 CYP2B1/genética , Terapia Genética/métodos , Ifosfamida/uso terapéutico , Neoplasias Pancreáticas/terapia , Profármacos/uso terapéutico , Animales , Cápsulas , Línea Celular , Citocromo P-450 CYP2B1/biosíntesis , Modelos Animales de Enfermedad , Expresión Génica , Humanos , Inyecciones , Ratones , Ratones Desnudos , Neoplasias Pancreáticas/tratamiento farmacológico
20.
Int J Pancreatol ; 25(1): 39-43, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10211420

RESUMEN

CONCLUSION: Preparation of DNA from pancreatic juice for subsequent polymerase chain reaction (PCR) is difficult, but manageable. The protocol presented offers a simple and fast solution. This method might be applicable to other complicated samples, such as saliva, would secretions, or stool washings. BACKGROUND: Of all the biological samples used for PCR amplification, pancreatic juice is the most problematic because of the presence of potential inhibitory substances and the amount of nucleases. This demands a DNA preparation procedure that is suitable for routine diagnostic PCR, and is therefore efficient and safe. This is particularly true for pancreatic juice obtained during routine endoscopy. METHODS: We describe here a simple method utilizing modified phenol/chloroform extraction and precipitation directly from native pancreatic juice suitable for diagnostic PCR applications, such as oncogenes. RESULTS: DNA could be prepared in quantitative amounts from routine endoscopic specimens. DNA could also be prepared from samples kept several days at room temperature.


Asunto(s)
ADN/aislamiento & purificación , Biología Molecular/métodos , Jugo Pancreático/química , Reacción en Cadena de la Polimerasa , Electroforesis en Gel de Agar , Genes ras , Humanos , Polimorfismo de Longitud del Fragmento de Restricción
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