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Biomedical subjects

A Kono

Publications and source records attributed to A Kono.

At least 91 records · Page 5Linked to original sources
PubMed1990

A somatostatin-secreting cell line established from a human pancreatic islet cell carcinoma (somatostatinoma): release experiment and immunohistochemical study.

Production and secretion of somatostatin (SRIF) were studied using a carcinoembryonic antigen (CEA)-producing cell line (QGP-1) established from a human pancreatic islet cell carcinoma. High concentrations of SRIF (274 +/- 51 ng/mg of protein, mean +/- SD, n = 5) and CEA (3083 +/- 347 ng/mg of protein, mean +/- SD, n = 5) were present in QGP-1 cells, and the basal secretion rates of SRIF and CEA by the cells (n = 5) were 46.4 +/- 4.8 and 1690 +/- 78 pg/10(5) cells/h, respectively. Immunohistochemical studies revealed the presence of SRIF in xenografts of QGP-1 cells and colocalization of SRIF and CEA. Secretion of SRIF by QGP-1 cells was stimulated in the presence of high K+ (50 mmol) and theophylline (10 mmol), but arginine (10 mmol) and glucose (300 mg/dl) had no effect on the SRIF secretion. The QGP-1 cell line may be useful for studying the regulation mechanism of SRIF secretion.

Adenoma, Islet Cell↗
PubMed1990

Pancreastatin producing cell line from human pancreatic islet cell tumor.

It has been characterized that cell line QGP-1 derived from human non-functioning pancreatic islet cell tumor produces human pancreastatin. Exponentially growing cultures produced 5.7 fmol of pancreastatin/10(6) cells/hr. Human pancreastatin immunoreactivities in plasma and tumor after xenografting with QGP-1 into nude mouse were 92.7 fmol/ml and 160.2 pmol/g wet weight, respectively. Immunocytochemical study revealed both chromogranin A and pancreastatin immunoreactive cells in the tumor. Gel filtrations of culture medium and tumor extract identified heterogenous molecular forms of PST-LI which eluted as large and smaller molecular species. These results suggest that plasma pancreastatin levels may be useful as a tumor marker of endocrine tumor of the pancreas, and the pancreastatin producing cell line may be useful for studies of the mechanism of secretions and processing of chromogranin A and pancreastatin.

Adenoma, Islet Cell↗
PubMed1990

Establishment and characterization of human pancreatic cancer cell lines in tissue culture and in nude mice.

Three human pancreatic cancer cell lines, designated as KP-1N, KP-2 and KP-3 have been established in both tissue cultures and in nude mice. The KP-1N and KP-3 tumors were obtained from liver metastases of pancreatic tumors and the KP-2 tumors was of primary pancreatic origin. The patients' tumors from which KP-1N and KP-2 were derived showed characteristics of adenocarcinoma, and the KP-3 tumor had adenosquamous carcinoma characteristics. Inoculations of samples from surgical specimens into athymic nude mice resulted in tumor formation, with the tumors histologically closely resembling the original neoplasms. Subcutaneous injections of the established cell lines also induced tumor formation and the tumors histologically resembled the original lesion in the cases of KP-2 and KP-3 tumors, but the KP-1N tumors in the mice were histologically different from the surgical specimen. The KP-1N, KP-2 and KP-3 cell lines have been cultured continuously in a medium supplemented with 10% fetal calf serum for more than 20, 21 and 17 months, respectively. The KP-2 and KP-3 cell lines produced and released carbohydrate antigen 19-9 into the spent medium but the KP-1N cell line did not. KP-1N and KP-3, produced liver metastases after intrasplenic injection into nude mice, whereas KP-2 produced few liver colonies. Cell lines highly metastatic to the liver, KP-1NLs and KP-3Ls, were isolated from the liver colonies of KP-1N and KP-3, respectively.

Aged↗
PubMed1989

Isolation and sequencing of a cDNA clone encoding 96 kDa sialoglycoprotein in rat liver lysosomal membranes.

We isolated and sequenced LGP 96, a cDNA clone corresponding to the entire coding sequence of the rat liver lysosomal membrane sialoglycoprotein with an apparent Mr of 96 K, LGP 96. The deduced amino acid sequence indicates that LGP 96 consists of 411 amino acid residues (Mr 45,163) and the 26 NH2-terminal residues presumably constitute a cleavable signal peptide. The major portion of LGP 96 resides on the luminal side of the lysosome and bears a large number of N-linked heavily sialylated complex type carbohydrate chains, giving the mature molecule of 96 kDa. The protein has 17 potential N-glycosylation sites and 32.1 and 65.3% sequence similarities in amino acid to LGP 107 and human lamp-2, respectively. The glycosylation sites are clustered into two domains separated by a hinge-like structure enriched with proline and threonine. LGP 96 possesses one putative transmembrane domain consisting of 24 hydrophobic amino acids near the COOH-terminus and contains a short cytoplasmic segment constituting 12 amino acid residues at the COOH-terminal end. Comparison of LGP 96 and recently cloned lysosomal membrane glycoprotein sequences reveals strong similarity in the putative transmembrane domain and cytoplasmic tail. It is very likely that these portions are important for the targeting of molecules to lysosomes. A comparison of LGP 96 and LGP 107 showed numerous structural similarities.

Amino Acid Sequence↗
PubMed1989

Isolation and sequencing of a cDNA clone encoding acid phosphatase in rat liver lysosomes.

A full length cDNA for acid phosphatase in rat liver lysosomes was isolated and sequenced. The predicted amino acid sequence comprises 423 residues (48,332 Da). A putative signal peptide of 30 residues is followed by the NH2-terminal sequence of lysosomal acid phosphatase (45,096 Da). The deduced NH2-terminal 18-residue sequence is identical with that determined directly for acid phosphatases purified from the rat liver lysosomal membranes. The primary structure deduced for acid phosphatase contains 9 potential N-glycosylation sites and a hydrophobic region which could function as a transmembrane domain. It exhibits 89% and 67% sequence similarities in amino acids and nucleic acids, respectively, to human lysosomal acid phosphatase. The amino acid sequence of the putative transmembrane segment shows a complete similarity to that of the human enzyme. Northern blot hybridization analysis identified a single species of acid phosphatase mRNA (2.2 kbp in length) in rat liver.

Acid Phosphatase↗
PubMed1989

Isolation and sequencing of a cDNA clone encoding 107 kDa sialoglycoprotein in rat liver lysosomal membranes.

A cDNA for 107 kDa sialoglycoprotein (LGP 107), the major protein component of rat liver lysosomal membranes, was isolated and sequenced. The 1.8 kbp cDNA contained an open reading frame encoding a polypeptide consisting of 386 amino acid residues (Mr 41,914). The deduced NH2-terminal 10-residue sequence is identical with that determined for purified LGP 107. The primary structure deduced for LGP 107 contains 20 potential N-glycosylation sites and exhibits 82.5, 43 and 60% sequence similarities to mouse LAMP-1, chicken LEP 100, and a 120-kDa human lysosomal glycoprotein, respectively. Among these lysosomal glycoproteins, the amino acid sequence of the putative transmembrane segment is highly conserved. Northern blot hybridization analysis identified a single species of LGP 107 mRNA (2.1 kbp in length) in rat liver, kidney, brain, lung, spleen, heart and pancreas, although its level in pancreas was very low.

Amino Acid Sequence↗
PubMed1988

Hemoglobin synthesis of both adult and fetal types in a human CML cell line.

We present evidence for the continuous erythroid differentiation of a cell line, KU-812-F, without the addition of an inducer. Erythroid differentiation of these cells was confirmed according to the following findings: 1) erythroid morphology; 2) existence of glycophorin A and carbonic anhydrase I as a membrane marker protein and an enzyme characteristic of erythroid cells, respectively; 3) synthesis of adult type (HbA and HbA2) and fetal type (HbF) hemoglobins, as detected on isoelectric focusing; and 4) transcription of the alpha-, beta-, and gamma-globin genes, as detected on Northern blot analysis.

Cell Differentiation↗
PubMed1987

Comparative influence of load versus inotropic states on indexes of ventricular contractility: experimental and theoretical analysis based on pressure-volume relationships.

We examined the quantitative influence of carefully controlled alterations in end-diastolic volume and afterload resistance on multiple simultaneously determined ejection and isovolumetric phase indexes of left ventricular contractile function in 23 isolated supported canine ventricles. The influence of load change on each index was compared with its sensitivity to inotropic stimulation, and this sensitivity was in turn contrasted to the response of the end-systolic pressure-volume relationship (ESPVR). Experimental data demonstrated various degrees of load sensitivity among the indexes, with a generally curvilinear relationship between load and index response for both preload and afterload alterations. The curvilinear nature of these relationships meant that over a select range of loading, many indexes demonstrated relative load independence. They also often displayed greater sensitivity to inotropic change than the ESPVR, and both factors help explain their enduring clinical utility. To further explore the influence of load and contractile state on several of the indexes, we developed a theoretical analysis, using variables common to pressure-volume relationships, in which these dependencies could be derived. The theoretical models fit very well with the experimental data, and reaffirmed the frequently curvilinear nature of the relationships. We conclude that while many clinical indexes of ventricular contractile function show significant load dependence, the information they provide can be reasonably interpreted within defined ranges of load and inotropic alteration. Any advantage of the ESPVR will derive not from the magnitude of its response to inotropic change, which is smaller than most other indexes, but from its relative insensitivity to load alteration over a wider range of load.

Animals↗
PubMed1985

A case with bronchogenic cyst diagnosed by reconstruction CT prior to surgery which showed cardiac abnormalities.

A case report of a patient with bronchogenic cyst who presented with cardiogenic symptoms was described. The precise diagnosis was finally made after completing various diagnostic procedures which included reconstruction computed tomography. The patient, a 30-year-old man, was admitted to our hospital because of palpitation, chest pain and fever of three weeks duration. An electrocardiogram (ECG) revealed evidence suggestive of left atrial overloading and frequent atrial premature beats. A chest roentgenogram showed an abnormal shadow behind the right upper portion of the heart and a cross-sectional echocardiogram revealed abnormal echoes with ill-defined margins in the left atrium. Computed tomography (CT) revealed the presence of the left atrial tumor but left atriography suggested that it was extracardiac and compressing the left atrium. Reconstruction CT was therefore performed and the cyst was diagnosed as being in a subcarinal position. A mobile calcified mass was also demonstrated by the CT. An operation was performed and a cyst, 6 X 3 cm, was removed almost completely and a histopathological diagnosis of bronchogenic cyst was made. In this particular case, ECG abnormalities which suggest atrial damage and the diagnostic usefulness of reconstruction CT are stressed.

Adult↗