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M Konishi

Publications and source records attributed to M Konishi.

At least 55 records · Page 3Linked to original sources
PubMed2000

Identification of a novel FGF, FGF-21, preferentially expressed in the liver.

We isolated cDNA encoding a novel FGF (210 amino acids) from mouse embryos. As this is the 21st documented FGF, we tentatively term it FGF-21. FGF-21 has a hydrophobic amino terminus ( approximately 30 amino acids), which is a typical signal sequence, and appears to be a secreted protein. The expression of FGF-21 mRNA in mouse adult tissues was examined by Northern blotting analysis. FGF-21 mRNA was most abundantly expressed in the liver, and also expressed in the thymus at lower levels. We also isolated human cDNA encoding FGF-21 (209 amino acids). Human FGF-21 is highly identical ( approximately 75% amino acid identity) to mouse FGF-21. Among human FGF family members, FGF-21 is most similar ( approximately 35% amino acid identity) to FGF-19.

Amino Acid Sequence↗
PubMed2000

Fibroblast growth factor-16 is a growth factor for embryonic brown adipocytes.

In rat embryos, fibroblast growth factor (FGF)-16 is predominantly expressed in brown adipose tissue. To elucidate the role of FGF-16, we examined the expression of FGF-16 mRNA in rat embryonic brown adipose tissue at different developmental stages by Northern blotting analysis and in situ hybridization. FGF-16 mRNA was expressed abundantly in brown adipose tissue during embryonic day 17. 5, embryonic days 17.5-19.5, and thereafter at lower levels into the neonatal period. The expression profile of FGF-16 mRNA well corresponds to the proliferative profile of embryonic brown adipose tissue reported. We also examined the mitogenic activity of recombinant rat FGF-16 for primary brown adipocytes prepared from rat embryonic brown adipose tissue. FGF-16 showed significant mitogenic activity for primary brown adipocytes. The mitogenic activity was found to be exerted by binding and activating FGF receptor-4 in the brown adipose tissue. As a great induction of proliferation of rat brown adipose tissue during cold acclimation was reported, we also examined the expression of FGF-16 mRNA in the brown adipose tissue during cold acclimation by Northern blotting analysis. The expression of FGF-16 mRNA was not increased, but rather decreased. The expression profile of FGF-16 mRNA and the mitogenic activity of FGF-16 reported here indicate that FGF-16 is a unique growth factor involved in proliferation of embryonic brown adipose tissue.

Adipose Tissue, Brown↗
PubMed2000

Malignant transformation and EGFR activation of immortalized mouse liver epithelial cells caused by HBV enhancer-X from a human hepatocellular carcinoma.

We have previously observed that all human hepatocellular carcinomas (HCCs) from HBV carriers examined had the integrated X region. In this study, HBV DNA was isolated from an integration site in one HCC that had a single, very small integrated viral DNA including the X region, but it had no expression of X gene as poly(A)RNA. It was found that HBV DNA was present between alphoid repetitive sequences, and it included Enhancer and X regions, encompassing the adr sequence from 910 to 1811. Nucleotides for 8 amino acids at the 3' end, a stop codon of X gene and a poly(A) signal downstream of X gene were lost by integration, and nucleotides for 7 amino acids and a stop codon were substituted by a connected alphoid sequence. When this cloned HBV DNA was transfected with an expression vector to an immortalized mouse liver epithelial cell line, MLE-10, malignant transformation occurred. Transformants having expressed poly(A)RNA of the X gene showed anchorage-independent growth in soft agar and tumor formation in the subcutis of nude mice. The mRNA level of EGFR was found to be remarkably enhanced in X-transformed cells, in contrast with the absence of this mRNA in parental and ras-transformed MLE-10. Our data provide evidence that the Enhancer-X region alone is the key contributor to the malignant change of pre-malignant liver cells in HBV carriers through activation of some specific genes, such as EGFR.

Amino Acid Sequence↗
PubMed2000

SLC7A7 genomic structure and novel variants in three Japanese lysinuric protein intolerance families.

Lysinuric protein intolerance (LPI) is a rare inherited disease caused by defective transport of the dibasic amino acids at the basolateral membranes of epithelial cells in the renal tubules and small intestine. The metabolic defect leads to brain dysfunction caused by hyperammonemia with a functional impairment of the urea cycle. Recently, mutations in the human SLC7A7 cDNA coding for y(+)LAT-1, which express dibasic amino acid transport activity, were reported to be responsible for LPI. In the present study, we examined the genomic structure of SLC7A7 by DNA sequencing of PCR products, and determined that the gene had 11 exons and 10 introns spanning about 18 kb of genomic DNA. We also identified an alternative RNA splicing at the 5' untranslated region of the SLC7A7 mRNA in human peripheral blood leukocytes, cultured lymphoblasts, and fibroblasts. As a result of mutational analysis of SLC7A7 in three Japanese LPI families, we found a nonsense mutation (R410X), a splicing mutation(911+1G>A) in intron 4, and four silent polymorphisms (201C/T, 445A/G, 784C/T, 946T/C). Identification of the genomic structure of SLC7A7 may provide a molecular basis for a genetic survey for LPI.

5' Untranslated Regions↗
PubMed2000

Transport of magnesium by two isoforms of the Na+-Ca2+ exchanger expressed in CCL39 fibroblasts.

Cytoplasmic concentrations of Ca2+ ([Ca2+]i) and Mg2+ ([Mg2+]i) were measured with fluorescent indicators in CCL39 cells, a cell line established from Chinese hamster lung fibroblasts, transfected with complementary deoxyribonucleic acid (cDNA) of the Na+-Ca2+ exchanger isolated either from canine heart (NCX1) or from rat brain (NCX3). Raising extracellular [Mg2+] to 10 mM increased Mg2+ influx and the resultant change in [Mg2+]i (delta[Mg2+]i) was monitored with furaptra under Ca2+-free conditions. In control (vector-transfected) cells, delta[Mg2+]i at 45 min was similar with or without extracellular Na+ (130 mM or 0 mM) and when [Na+]i was raised by 1 mM ouabain treatment. delta[Mg2+]i in NCX1-transfected cells was attenuated significantly in the presence of 130 mM Na+, but became comparable to (or slightly larger than) that in control cells on either removal of extracellular Na+ or treatment with 1 mM ouabain. Cells expressing NCX3 showed an intermediate dependence of delta[Mg2+]i on Na+, probably reflecting a lower degree of expression of the exchanger protein. Extracellular Na+-dependent changes in [Ca2+]i (measured with fura-2 in the presence of extracellular Ca2+ and 10 microM ionomycin, a Ca2+ ionophore) were minimal in control cells, marked in the NCX1-transfected cells and intermediate in the NCX3-transfected cells. These results suggest that the Na+-Ca2+ exchanger (either NCX1 or NCX3) can transport Mg2+ and may play a role in the extrusion of magnesium from cells.

Animals↗
PubMed2000

Distal pancreatectomy with resection of the celiac axis and reconstruction of the hepatic artery for carcinoma of the body and tail of the pancreas.

Distal pancreatectomy with resection of the celiac axis can increase resectability of carcinoma of the body and tail of the pancreas. We performed reconstruction of the hepatic artery to avoid complications caused by a decrease in hepatic arterial flow. We carried out distal pancreatectomy with resection of the celiac axis for carcinoma of the body and tail of the pancreas in four patients. When pulsation in the proper hepatic artery was weak after occlusion of the celiac axis, we performed reconstruction of the hepatic artery, using the splenic artery, which had been taken beforehand from the resected specimen. In two patients, we performed reconstruction of the hepatic artery. These two patients underwent reconstruction of the portal vein combined with prolonged clamping of the portal vein. Levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were elevated just after the operation, but recovered to normal levels within 10 days. No complications related to hepatic ischemia were observed. These results suggested that reconstruction of the hepatic artery allowed us to safely perform distal pancreatectomy with resection of the celiac axis for carcinoma of the body and tail of the pancreas.

Aged↗
PubMed2000

Extended right hepatic lobectomy with resection of inferior vena cava and portal vein for intrahepatic cholangiocarcinoma.

We report a case of intrahepatic cholangiocarcinoma treated by extended right lobectomy and resection of the inferior vena cava (IVC) and portal vein. A 53-year-old man was referred with elevated serum alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (gamma-GTP) levels on April 23, 1999. He was not jaundiced and did not have any symptoms. Endoscopic retrograde cholangiopancreatography (ERCP) revealed irregular strictures in both the anterior and posterior segmental ducts. Contrast-enhanced computed tomography (CT) scan demonstrated a low-density tumor with an unclear margin in the right lobe of the liver. The patient underwent extended right hepatic lobectomy and total caudate lobectomy. Partial resection of the IVC (6 cm) was performed under total hepatic vascular exclusion. The main portal trunk and left portal vein were resected and reconstructed with an end-to-end anastomosis. Macroscopically, a 5.0 x 5.0 x 4.5-cm periductal infiltrating-type tumor occupied the right hepatic parenchyma along the posterior and anterior segmental ducts. Histological examination revealed moderately differentiated tubular adenocarcinoma with marked perineural invasion. Lymph node metastasis was observed in the hepatoduodenal ligament and posterior surface of the pancreatic head. The resected margins of the common bile duct and left hepatic duct were free of tumor. The patient's postoperative course was uneventful, and he was discharged from hospital on the 28th postoperative day. Nine months after the operation, he suddenly developed obstructive jaundice, and died with recurrent disease. This is the first reported case of intrahepatic cholangiocarcinoma treated with major hepatectomy and resection of the IVC and portal vein except ex situ procedure. This aggressive surgical approach may offer hope for patients with intrahepatic cholangiocarcinoma involving the IVC.

Anastomosis, Surgical↗
PubMed2000

Epithelioid hemangioendothelioma of the liver.

Epithelioid hemangioendothelioma (EH) of the liver is a rare tumor and is difficult to differentiate from cholangiocellular carcinoma or metastatic liver tumor on image diagnosis. A case of curatively resected EH of the liver is reported. A 48-year-old woman was admitted because she had a mass in the liver. Cholangiocellular carcinoma was suspected preoperatively. Right trisegmentectomy of the liver, combined with bile duct resection and portal vein resection and reconstruction, was performed. Characteristic macro- and microscopic findings of the resected specimen revealed EH of the liver. The patient has survived for more than 6 years without recurrence. Because of the tendency of EH of the liver to appear in multiple or scattered forms, only 12 cases of resection for EH have been reported.

Female↗
PubMed2000

Association of autosomal dominantly inherited corneal dystrophies with BIGH3 gene mutations in Japan.

PURPOSE: To evaluate the incidence of BIGH3 gene mutations in 164 unrelated Japanese patients with corneal stromal dystrophies with an autosomal dominant trait. METHODS: Data were collected at two major institutions in the eastern and western parts of Japan, where molecular genetic analysis was performed for diagnostic purpose. RESULTS: The incidence of mutations was ranked as follows: 118 patients (72%), the R124H mutation associated with Avellino corneal dystrophy; 23 patients (14%), the R124C mutation associated with lattice corneal dystrophy type 1; and 10 patients (6%), the P501T mutation associated with lattice corneal dystrophy type 3A. CONCLUSION: Avellino corneal dystrophy associated with the R124H mutation is the most common form of corneal stromal dystrophy in Japan. This dystrophy, which is diagnosed histopathologically, has also been called granular corneal dystrophy in Japan. The classification of these diseases according to genetic pathogenesis may be more appropriate than is the use of clinical or histological findings.

Corneal Dystrophies, Hereditary↗
PubMed2000

Auditory processing in birds.

Over the past year, much progress has been achieved in the study of both the peripheral and the central auditory systems of birds. Significant advances have been made in the study of hair cells, including elucidation of the mechanisms of selectivity for sound frequency, functional differentiation, efferent innervation, and regeneration. Most of the studies of central auditory neurones have concerned the developmental and physiological correlates of vocal learning in songbirds and sound localisation in owls.

Acoustic Stimulation↗
PubMed2000

Study of sound localization by owls and its relevance to humans.

Human psychoacoustical studies have been the main sources of information from which the brain mechanisms of sound localization are inferred. The value of animal models would be limited, if humans and the animals did not share the same perceptual experience and the neural mechanisms for it. Barn owls and humans use the same method of computing interaural time differences for localization in the horizontal plane. The behavioral performance of owls and its neural bases are consistent with some of the theories developed for human sound localization. Neural theories of sound localization largely owe their origin to the study of sound localization by humans, even though little is known about the physiological properties of the human auditory system. One of these ideas is binaural cross-correlation which assumes that the human brain performs a process similar to mathematical cross-correlation to measure the interaural time difference for localization in the horizontal plane. The most complete set of neural evidence for this theory comes from the study of sound localization and its brain mechanisms in barn owls, although partial support is also available from studies on laboratory mammals. Animal models of human sensory perception make two implicit assumptions; animals and humans experience the same percept and the same neural mechanism underlies the creation of the percept. These assumptions are hard to prove for obvious reason. This article reviews several lines of evidence that similar neural mechanisms must underlie the perception of sound locations in humans and owls.

Animals↗
PubMed2000

Long-term survival and prognostic factors in the surgical treatment of mass-forming type cholangiocarcinoma.

BACKGROUND: Mass-forming type cholangiocarcinoma is a distinct from of cholangiocellular carcinoma, with pathologic and biologic behavior different from those of other types. The clinical consequences of these differences have never been clarified. METHODS: Fifty-two consecutive patients (32 men and 20 women, mean age 62 years) with mass-forming type cholangiocarcinoma that had been treated with curative surgical resection between 1980 and 1998 were retrospectively evaluated. Long-term survival and disease-free survival were calculated, and univariate and multivariate analysis of various prognostic factors was conducted. RESULTS: The 30-day postoperative mortality rate was 2%, and the overall and disease-free 5-year survival rates were 36% and 34%, respectively. Univariate analysis identified 5 significant risk factors for overall survival: surgical margin, lymph node metastasis, lymph node dissection, vascular invasion, and left-side location of the main tumor. Two risk factors were identified for disease-free survival: surgical margin and lymph node metastasis. Multivariate analysis confirmed that surgical margin, lymph node metastasis, and vascular invasion were independently significant variables for overall survival. CONCLUSIONS: This is the first reported study on the effectiveness of liver resection for the treatment of mass-forming type cholangiocarcinoma, showing that surgical therapy can prolong survival if local radicality can be achieved and lymph-node metastases are absent.

Adult↗
PubMed2000

Intrahepatic inflow areas of the drainage vein of the gallbladder: analysis by angio-CT.

BACKGROUND: The drainage veins of the gallbladder (cystic veins) are important hepatic metastatic routes of gallbladder cancer. We studied the cystic vein inflow portions of the intrahepatic vessels by computed tomography during angiography (angio-CT). METHODS: The subjects were 27 unoperated pancreatic-biliary patients. After superselective catheterization of the cystic artery, angio-CT was performed, and cystic veins and sinusoidal filling were visualized. We identified the cystic vein inflow routes and the vessels they fed. RESULTS: We found 72 cystic veins in 26 patients. All cystic veins flowed into the intrahepatic portal branches or sinusoids. The cystic veins took either of two routes: one into the liver through the hepatic hilum (17 patients, 21 veins), taken mainly by the portal branch for subsegment 4a (P4a), the anterior portal branch, and the umbilical portion of the portal branch; and the other through the hepatic bed (23 patients, 51 veins), taken mainly by S4a sinusoid, S5 sinusoid, P4a, and P5. CONCLUSIONS: Angio-CT is useful for detecting the cystic vein inflow portions of the intrahepatic vessels. It makes possible identification of areas where there is a possibility for micrometastasis of the gallbladder cancer.

Adult↗