• 제목/요약/키워드: Islet

검색결과 208건 처리시간 0.032초

A Role of Endogenous Somatostatin in Exocrine Secretion Induced by Intrapancreatic Cholinergic Activation

  • Park, Hyung-Seo;Park, In-Sun;Kwon, Hyeok-Yil;Lee, Yun-Lyul;Park, Hyoung-Jin
    • The Korean Journal of Physiology and Pharmacology
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    • 제2권2호
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    • pp.185-192
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    • 1998
  • A role of endogenous somatostatin in pancreatic exocrine secretion induced by intrapancreatic cholinergic activation was studied in the isolated rat pancreas perfused with modified Krebs-Henseleit solution. Intrapancreatic neurons were activated by electrical field stimulation (EFS: 15 V, 2 msec and 8 Hz). Pancreatic exocrine secretion, including volume flow and amylase output, and release of somatostatin from the pancreas were respectively determined. Somatostatin cells in the islet were stained with an immunoperoxidase method. EFS significantly increased pancreatic volume flow and amylase output, which were reduced by atropine by 59% and 78%, respectively. Intraarterial infusion of either pertussis toxin or a somatostatin antagonist resulted in a further increase in the EFS-evoked pancreatic secretion. EFS also further elevated exocrine secretion in the pancreas treated with cysteamine, which was completely restored by intraarterial infusion of somatostatin. EFS significantly increased not only the number of immunoreactive somatostatin cells in the islet but also the concentration of immunoreactive somatostatin in portal effluent. It is concluded from the above results that intrapancreatic cholinergic activation elevates pancreatic exocrine secretion as well as release of endogenous somatostatin. Endogenous somatostatin exerts an inhibitory influence on exocrine secretion induced by intrapancreatic cholinergic activation via the islet-acinar portal system in the isolated pancreas of the rat.

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$^{99m}Tc$-colloid 섭취를 보인 췌장의 도세포종 : 증례보고 (Radiocolloid Uptake in the Pancreas Islet Cell Tumor: Case Report)

  • 양우진;정수교;연수경;신경섭;박용휘
    • 대한핵의학회지
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    • 제28권1호
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    • pp.145-147
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    • 1994
  • Colloid uptake in various hepatic conditions such as focal nodular hyperplasia, regenerating nodules in the cirrhotic liver, hamartoma, hemangioma and rarely hepatoma has been documented. Extrahepatic tumors may show colloid uptake and they include splenic hemangioma, malignant fibrous histiocytoma, breast carcinoma and Kaposi's sarcoma. The mechanism of colloid uptake in those lesions is associated with phagocytic activity in or around the tumors. We report a pancreas islet cell tumor that showed colloid uptake on $^{99m}Tc$-phytate liver scan without histologic evidence of phagocytosis by tumor cells or infiltration of phagocytes in the tumor Microscopically the tumor was highly vascular and showed diffuse hemorrhage throughtout the tumor. We postulated that extravasation of the colloid into the tumor insterstitium caused nonspecific colloid uptake in this tumor. It is expected that hemorrhagic tumor may show nonspecific colloid uptake without phagocytosis in or about the lesion.

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Functional Characteristics of C-terminal Lysine to Cysteine Mutant Form of CTLA-4Ig

  • Kim, Bongi;Shin, Jun-Seop;Park, Chung-Gyu
    • IMMUNE NETWORK
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    • 제13권1호
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    • pp.16-24
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    • 2013
  • CTLA-4Ig is regarded as an inhibitory agent of the T cell proliferation via blocking the costimulatory signal which is essential for full T cell activation. To improve applicability, we developed the CTLA-4Ig-CTKC in which the c-terminal lysine had been replaced by cysteine through single amino acid change. The single amino acid mutation of c-terminus of CTLA-4Ig was performed by PCR and was checked by in vitro transcription and translation. DNA construct of mutant form was transfected to Chinese hamster ovary (CHO) cells by electroporation. The purified proteins were confirmed by Western blot and B7-1 binding assay for their binding ability. The suppressive capacity of CTLA-4Ig-CTKC was evaluated by the mixed lymphocyte reaction (MLR) and in the allogeneic pancreatic islet transplantation model. CTLA-4Ig-CTKC maintained binding ability to B7-1 molecule and effectively inhibits T cell proliferation in MLR. In the murine allogeneic pancreatic islet transplantation, short-term treatment of CTLA-4Ig-CTKC prolonged the graft survival over 100 days. CTLA-4Ig-CTKC effectively inhibits immune response both in MLR and in allogeneic islet transplantation model, indicating that single amino acid mutation does not affect the inhibitory function of CTLA-4Ig. CTLA-4Ig-CTKC can be used in vehicle-mediated drug delivery system such as liposome conjugation.

Cytokine Synergism in Apoptosis: Its Role in Diabetes and Cancer

  • Lee, Myung-Shik
    • BMB Reports
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    • 제35권1호
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    • pp.54-60
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    • 2002
  • The effects of individual cytokine on apoptosis have been extensively studied. However, the effect of the cytokine combination, or the synergistic effect of cytokines on cell death, has not been widely studied, though synergism between cytokines has been documented in a variety of biological situations. In our effort to identify the final death effector molecule(s) in autoimmune diabetes, we inadvertently became interested in the cytokine synergism. We discovered that $IFN{\gamma}/TNF{\alpha}$ synergism, rather than the Fas ligand as currently believed, is responsible for the apoptosis of pancreatic islet cells both in vitro and in vivo. We also studied similar cytokine synergism in cancer cell deaths, and noted the similarities and dissimilarities between cancer cell death and islet cell death.

제주도 남부연안역의 생물생태학적 기초연구 1.가피도와 마라도 조간대의 저서무척추동물의 분포와 군집구조 (Bioecological Studies of the Southern Coastal Area in Cheju Island -1. Distribution and Community Structure of the Benthic Macroinvertebrates in Gapa and Mara Islets -)

  • 이정재
    • 한국패류학회지
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    • 제7권1호
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    • pp.49-57
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    • 1991
  • A study on the distribution and community structure of the benthic macroinvertebrates on the intertidal zones of Gapa and Mara islets were carried out from March to June 1991. The macroinvertebrates collected and identified were composed of 7 phyla, 14 classes, 29 orders, 68 families and 132 speies in Gapa islet and of 7 phyla, 12 classes, 23 orders, 49 familis and 90 species in Maara islet. The first and second dominant species and the community dominance indices of the upper tidal zones of Gapa and Mara islets were Nodilittorina exigua, Pollicipes mitella and 79.01, 69.77 respectively. However, the dominant species of the middle and lower intertidal zones of the two islets were not identities and different among the tidal zones.

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Infection status of Paragonimus westermani metacercariae in crayfish (Cambaroides similis) collected from Bogildo (Islet), Wando-gun, Chollanam-do, Korea

  • Shin, Myeong-Heon;min, Duk-Young
    • Parasites, Hosts and Diseases
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    • 제37권1호
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    • pp.55-57
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    • 1999
  • During the period from October 1996 to November 1998, the infection status of Paragonimus westermani metacercariae in freshwater crayfish (Cambaroides similis) collected from Bogildo (islet), Wando-gun, Chollanam-do, which is known for an endemic area of P. westermani in Korea, were examined. The average infection rate of Paragonimus metacercariae in crayfish was 88.6%, and mean number of metacercariae per infected crayfish was 30.2. This metacercarial density was the highest in the group of weight in 7.1-9.0 g. These results suggest that the natural life cycle of P. westermani is still well-preserved in Bogildo.

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전라남도 완도군 보길도에서의 폐흡충(paragonimus westermani) 중간숙주 조사 (A Study on the Intermediate Hosts of Paragonimus westermani in Bogil Islet, Chonra-Nam-Do, Korea)

  • 김재진;장재경;정평림;소진탁
    • 한국패류학회지
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    • 제1권1호
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    • pp.19-23
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    • 1985
  • Collections of Semisulcospira snails and crayfishes were made to detect out larval trematodes in Bogil Islet, Wando-Gun, Chonra-Nam-Do, Korea in August, 1985. In addition, intradermal test to figure out the prevalence rate of paragonimiasis in the islanders was also carried out. The results are summarized as follows: 1) Nineteen out of 186 examinees(10.2%) showed positive reactions by intradermal test with Paragonimus antigen. 2) Forty four snails out of 182 snails collected were infected with trematode cercariae. These larvae were Metagonimus sp., Cercaria yoshidae, Cercaria incerta and Cercarianipponensis. 3) Metacercarial incidence of Paragonimus westermani in crayfish was 65.4%. Mean number of metacercariae per crayfish was 6.5.

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Ectopic insulinoma in a dog with insulin-induced hypoglycemia: a case report

  • Jiwon Kim;Insun Hwang;Danbee Kwon;Kanghyo Park;Hakyoung Yoon
    • Journal of Veterinary Science
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    • 제24권3호
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    • pp.39.1-39.6
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    • 2023
  • A 7-year-old spayed female Shih Tzu dog was presented for evaluation of recurrent hypoglycemia. Serum insulin levels during hypoglycemia were 35.3 µIU/mL. Ultrasonography and computed tomography showed a mesenteric nodule between the kidney and the portal vein, but no pancreatic mass was observed. During surgery, the nodule had neither anatomical adhesions nor vascular connections to the pancreas. Pancreatic inspection and palpation revealed no abnormalities. Hypoglycemia improved after resection of the nodule. Histopathological examination confirmed the nodule to be an islet cell carcinoma. Although extremely rare, ectopic insulinoma should be considered as a possible cause of insulininduced hypoglycemia in dogs.