Objective To review experience in preoperative detection of islet cell tumors using multislice computed tomography （MSCT） and summarize various imaging features of functioning islet cell tumors on enhanced MSCT. Me...Objective To review experience in preoperative detection of islet cell tumors using multislice computed tomography （MSCT） and summarize various imaging features of functioning islet cell tumors on enhanced MSCT. Methods Seventy patients with clinical or pathological diagnosis of functioning pancreatic islet cell tumor between October 2003 and February 2007 were included in this retrospective study. Seventy-four enhanced MSCT scans in these patients were identified. All MSCT scans were interpreted by two experienced radiologists by consensus interpretation. Surgery and pathology reports were used to confirm the diagnosis, localization, and size of tumors. Results Totally, 73 functioning islet cell tumors including 65 benign insulinomas, 2 benign glucagonomas, 3 malignant insulinomas, and 3 malignant glucagonomas were pathologically diagnosed. Tumors in only two cases were not found by MSCT. In 67 benign lesions, 32 showed typical enhancement style, 21 showed prolonged enhancement in portal venous phase, 4 showed delayed enhancement, 4 had iso-dense enhancement with normal pancreatic parenchyma, 2 had no enhancement at all in arterial phase and portal venous phase, and 4 had inhomogeneous enhancement with necrosis or cyst-formation. Patchy or spotty calcifications were found in 3 of the 67 tumors. In 6 malignant islet cell tumors, vessel invasion （2/6） and bowel invasion （1/6） were seen. Different enhancement patterns were shown. All hepatic metastases showed hyper-enhancement during their arterial phase. Conelttsions Pancreatic islet cell tumor may display a wide spectrum of presentations in MSCT. Tumors with unusual appearances often present as diagnostic challenges. Non-contrast and post-contrast multiphase scans are recommended for the localization of functioning islet cell tumors.展开更多
Objective.To in vestigate clinicopathologic characteristics and surgical results of nonfunctiona l islet cell tumors.Methods.We performed retrospective analysis of50patient s with nonfunctional islet cell tumor treat-...Objective.To in vestigate clinicopathologic characteristics and surgical results of nonfunctiona l islet cell tumors.Methods.We performed retrospective analysis of50patient s with nonfunctional islet cell tumor treat-ed at Peking Union Medical College Hospital from July1968to July1999,and summarized clinical symptoms and signs,primary diagnosis before surgery,surgical treatments,pathologic and im munohisto-logical characteristics.Results.Of the50cases examined from July 1968to July1999,12were found during physical examinations. The most common symptoms were upper abdominal pain and upper abdominal dis-com fort,which appeared in20casesand17casesrespectively,an d the most common sign was abdominal masses.B-ultrasound and CT are the most commonly used means for preoperative examination,with posit ive rates of97.8%and100%respectively.Op-e rative mortality was2%.Five-year survival rate of radical surgery of maligna nt cases was75%.Immuno-histological examinations showed that tumors rich i n multi-peptide linked hormones,neuron-specific eno-lase and chromaffin were in65%cases,90.6%and73.3% respectively.The positive rates of insulin,glucagons,somatostatin,pancreat ic polypeptide,gastrin and vasoactive intestinal peptide were68.2% ,51.2%,42.9%,40% ,25%and15.8%respectively.Conclusion.Nonfuncti onal islet cell tumors lack diagnostic specificity.Ultrasound and CT are primar y examination methods.Immunohistological analysis indicates different hormones ,but lacks the presence of related clinical symptoms.Surgery is an effective treatment for nonfunctional islet cell tumors,and even for those with distal m etastasis,immediate surgical removal and treatment can improve prognosis.展开更多
Objective To evaluate islet β cell response to intravenous glucagon （ a non-glucose secretagogue） stimulation in diabetes mellitus. Methods Nineteen patients with type 1 diabetes （T1 D） and 131 patients with typ...Objective To evaluate islet β cell response to intravenous glucagon （ a non-glucose secretagogue） stimulation in diabetes mellitus. Methods Nineteen patients with type 1 diabetes （T1 D） and 131 patients with type 2 diabetes （T2D） were recruited in this study. T2D patients were divided into two groups according to therapy： 36 cases treated with insulin and 95 cases treated with diet or oral therapy. The serum C-peptide levels were determined at fasting and six minutes after intra- venous injection of 1 mg of ghicagon. Results Both fasting and 6-minute post-ghicagon-stimulated C-peptide levels in T1D patients were significantly lower than those of T2D patients （0. 76±0. 36 ng/mL vs. 1.81±0. 78 ng/mL, P 〈 0.05 ; 0.88±0.42 ng/mL vs. 3.68±0. 98 ng/mL, P 〈 0. 05 ）. In T1D patients, the C-peptide level after injection of ghicagon was similar to the fasting level. In T2D, patients treated with diet or oral drug had a significantly greater fasting and stimulated C-peptide level than those patients received insulin therapy （2.45±0. 93 ng/mL vs. 1.61±0. 68 ng/mL, P 〈 0.05 ; 5.26±1.24 ng/mL vs. 2.15±0.76 ng/mL, P 〈 0.05 ）. The serum C-peptide level after ghicagon stimulation was positively correlated with C-peptide levels at fasting in all three groups （ r = 0.76, P 〈 0.05 ）. Conclusions The 6-minute ghicagon test is valuable in assessing the function of islet β cell in patients with diabetes mellitus. It is helpful for diagnosis and treatment of diabetes mellitus.展开更多
Objective To explore the mechanisms of differentiation and development of pancreatic endocrine cells as well as pancreatic regeneration.Methods Human embryonic pancreatic tissue at 7-14 weeks of gestation was collecte...Objective To explore the mechanisms of differentiation and development of pancreatic endocrine cells as well as pancreatic regeneration.Methods Human embryonic pancreatic tissue at 7-14 weeks of gestation was collected.Diabetes mellitus rat model was induced with 65 mg/kg of streptozotocin.Insulin, glucagon, somatostatin, nestin, and cytokeratin 19 (CK19) of pancreatic tissues were observed by immunohistochemistry.Results At 9 weeks of gestation, pancreatic epithelial cells began to co-express insulin, glucagon, somatostatin, and CK19 before migration.Islet cells gradually congregated along with the increase of aging, and at 14 weeks of gestation histological examination showed islet formation.At 12 weeks of gestation, nestin-positive cells could be seen in the pancreatic mesenchyme.During early embryogenesis, islet cells of pancreatic ducts co-expressed insulin, glucagon, and somatostatin.During pancreatic regeneration after damage, nestin expression of islet cells increased.Conclusion In the early stage of embryogenesis, islet cells of primary pancreatic ducts can be differentiated to multipotential endocrine cells before migration.During tissue regeneration, pancreatic stem cells may differentiate and proliferate to form pancreatic islet.展开更多
文摘Objective To review experience in preoperative detection of islet cell tumors using multislice computed tomography （MSCT） and summarize various imaging features of functioning islet cell tumors on enhanced MSCT. Methods Seventy patients with clinical or pathological diagnosis of functioning pancreatic islet cell tumor between October 2003 and February 2007 were included in this retrospective study. Seventy-four enhanced MSCT scans in these patients were identified. All MSCT scans were interpreted by two experienced radiologists by consensus interpretation. Surgery and pathology reports were used to confirm the diagnosis, localization, and size of tumors. Results Totally, 73 functioning islet cell tumors including 65 benign insulinomas, 2 benign glucagonomas, 3 malignant insulinomas, and 3 malignant glucagonomas were pathologically diagnosed. Tumors in only two cases were not found by MSCT. In 67 benign lesions, 32 showed typical enhancement style, 21 showed prolonged enhancement in portal venous phase, 4 showed delayed enhancement, 4 had iso-dense enhancement with normal pancreatic parenchyma, 2 had no enhancement at all in arterial phase and portal venous phase, and 4 had inhomogeneous enhancement with necrosis or cyst-formation. Patchy or spotty calcifications were found in 3 of the 67 tumors. In 6 malignant islet cell tumors, vessel invasion （2/6） and bowel invasion （1/6） were seen. Different enhancement patterns were shown. All hepatic metastases showed hyper-enhancement during their arterial phase. Conelttsions Pancreatic islet cell tumor may display a wide spectrum of presentations in MSCT. Tumors with unusual appearances often present as diagnostic challenges. Non-contrast and post-contrast multiphase scans are recommended for the localization of functioning islet cell tumors.
文摘Objective.To in vestigate clinicopathologic characteristics and surgical results of nonfunctiona l islet cell tumors.Methods.We performed retrospective analysis of50patient s with nonfunctional islet cell tumor treat-ed at Peking Union Medical College Hospital from July1968to July1999,and summarized clinical symptoms and signs,primary diagnosis before surgery,surgical treatments,pathologic and im munohisto-logical characteristics.Results.Of the50cases examined from July 1968to July1999,12were found during physical examinations. The most common symptoms were upper abdominal pain and upper abdominal dis-com fort,which appeared in20casesand17casesrespectively,an d the most common sign was abdominal masses.B-ultrasound and CT are the most commonly used means for preoperative examination,with posit ive rates of97.8%and100%respectively.Op-e rative mortality was2%.Five-year survival rate of radical surgery of maligna nt cases was75%.Immuno-histological examinations showed that tumors rich i n multi-peptide linked hormones,neuron-specific eno-lase and chromaffin were in65%cases,90.6%and73.3% respectively.The positive rates of insulin,glucagons,somatostatin,pancreat ic polypeptide,gastrin and vasoactive intestinal peptide were68.2% ,51.2%,42.9%,40% ,25%and15.8%respectively.Conclusion.Nonfuncti onal islet cell tumors lack diagnostic specificity.Ultrasound and CT are primar y examination methods.Immunohistological analysis indicates different hormones ,but lacks the presence of related clinical symptoms.Surgery is an effective treatment for nonfunctional islet cell tumors,and even for those with distal m etastasis,immediate surgical removal and treatment can improve prognosis.
文摘Objective To evaluate islet β cell response to intravenous glucagon （ a non-glucose secretagogue） stimulation in diabetes mellitus. Methods Nineteen patients with type 1 diabetes （T1 D） and 131 patients with type 2 diabetes （T2D） were recruited in this study. T2D patients were divided into two groups according to therapy： 36 cases treated with insulin and 95 cases treated with diet or oral therapy. The serum C-peptide levels were determined at fasting and six minutes after intra- venous injection of 1 mg of ghicagon. Results Both fasting and 6-minute post-ghicagon-stimulated C-peptide levels in T1D patients were significantly lower than those of T2D patients （0. 76±0. 36 ng/mL vs. 1.81±0. 78 ng/mL, P 〈 0.05 ; 0.88±0.42 ng/mL vs. 3.68±0. 98 ng/mL, P 〈 0. 05 ）. In T1D patients, the C-peptide level after injection of ghicagon was similar to the fasting level. In T2D, patients treated with diet or oral drug had a significantly greater fasting and stimulated C-peptide level than those patients received insulin therapy （2.45±0. 93 ng/mL vs. 1.61±0. 68 ng/mL, P 〈 0.05 ; 5.26±1.24 ng/mL vs. 2.15±0.76 ng/mL, P 〈 0.05 ）. The serum C-peptide level after ghicagon stimulation was positively correlated with C-peptide levels at fasting in all three groups （ r = 0.76, P 〈 0.05 ）. Conclusions The 6-minute ghicagon test is valuable in assessing the function of islet β cell in patients with diabetes mellitus. It is helpful for diagnosis and treatment of diabetes mellitus.
文摘Objective To explore the mechanisms of differentiation and development of pancreatic endocrine cells as well as pancreatic regeneration.Methods Human embryonic pancreatic tissue at 7-14 weeks of gestation was collected.Diabetes mellitus rat model was induced with 65 mg/kg of streptozotocin.Insulin, glucagon, somatostatin, nestin, and cytokeratin 19 (CK19) of pancreatic tissues were observed by immunohistochemistry.Results At 9 weeks of gestation, pancreatic epithelial cells began to co-express insulin, glucagon, somatostatin, and CK19 before migration.Islet cells gradually congregated along with the increase of aging, and at 14 weeks of gestation histological examination showed islet formation.At 12 weeks of gestation, nestin-positive cells could be seen in the pancreatic mesenchyme.During early embryogenesis, islet cells of pancreatic ducts co-expressed insulin, glucagon, and somatostatin.During pancreatic regeneration after damage, nestin expression of islet cells increased.Conclusion In the early stage of embryogenesis, islet cells of primary pancreatic ducts can be differentiated to multipotential endocrine cells before migration.During tissue regeneration, pancreatic stem cells may differentiate and proliferate to form pancreatic islet.
