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Biomedical subjects

H Ando

Publications and source records attributed to H Ando.

At least 217 records · Page 12Linked to original sources
PubMed1996

10Sa RNA complements the temperature-sensitive phenotype caused by a mutation in the phosphoribosyl pyrophosphate synthetase (prs) gene in Escherichia coli.

From Escherichia coli cells with a deletion in the ssrA gene that encodes 10Sa RNA after treatment with a mutagen, we isolated two temperature-sensitive mutants, which we designated TS15 and TS101. The temperature-sensitive (ts) phenotype of the mutants could be overcome by introduction of the wild-type ssrA gene but not by the mutants of ssrA. By a complementation test using Kohara's mini-set of clones and by subcloning of a fragment from the phage clone 246, we found that both mutations were in the prs gene that encodes phosphoribosyl pyrophosphate synthetase. Sequencing of the mutant prs gene of TS101 showed that residues 215, cysteine, in the encoded protein had been changed to tyrosine. That such a mutant exists suggests that 10Sa RNA associate with the prs gene product in a functional way.

Escherichia coli↗
PubMed1996

Synthesis and release of glycosylated prolactin in transfected cells with human prolactin complementary deoxyribonucleic acid.

To analyze how the synthesis and release of glycosylated PRL (G-PRL) is regulated, we transfected human PRL complementary deoxyribonucleic acid (cDNA) into three different cell lines consisting of GH3 cells that originated in rat pituitary tissue, Chinese hamster ovary cells, and COS-1 cells generated from monkey renal tissue. 35S-labeled PRLs produced by the cells were immunoprecipitated with anti-human PRL antiserum, and the ratios of G-PRL to total PRL were compared. PRLs of 23 kDa and 25 kDa were detected in the cell lysate and medium. The 25-kDa PRL was confirmed to be a glycosylated form by endoglycosidase treatments. The ratios of G-PRL/total PRL were 0.17-0.33, which were similar in lysates and media and among different cell lines. Pulse-chase experiments revealed that the autonomaous secretion rates of G-PRL and non-glycosylated PRL were almost identical. These results indicate that synthesis and secretion kinetics of human PRL may not be affected by its glycosylation in the cells transfected with PRL cDNA.

Animals↗
PubMed1996

Two types of cDNAs encoding proopiomelanocortin of sockeye salmon, Oncorhynchus nerka.

To investigate regulatory mechanisms of proopiomelanocortin (POMC) gene expression in sockeye salmon, we have isolated and characterized cDNAs encoding two types of sockeye salmon POMC, which are referred to as ssPOMC-A and -B. Two types of PCR products were amplified from total RNA of sockeye salmon pituitaries by use of rainbow trout sequences. Full length cDNA clones encoding ssPOMC-A and ssPOMC-B were obtained from a pituitary cDNA library of sockeye salmon using the PCR products as probes. The ssPOMC-A and -B cDNAs have a length of 1072 and 1709 bps, respectively. Northern blot analysis showed that both ssPOMC-A and -B mRNAs were expressed only in the pituitary, and their sizes were about 1.2 kb and 1.8 kb, respectively. The presence of two ssPOMC genes was confirmed by Southern blot analysis of genomic DNA obtained from a single sockeye salmon. The deduced amino acid sequences of the ssPOMC-A and -B contained 230 and 226 residues, respectively. The amino terminal of beta-endorphin in ssPOMC-B which corresponds to Met-enkephalin domain is YSGFM, which is different from YGGFM of Met-enkephalin found in many other vertebrate species. The homology of nucleotide sequences between ssPOMC-A and -B is 59% in the entire coding region, whereas alpha-MSH coding regions are highly homologous (91%). Although the deduced amino acid sequences of ssPOMs show 43% overall similarity, their hydropathy profiles are coincident with those of several other vertebrate species, particularly the amino terminal of N-terminal peptide (NPP) shows almost the same pattern with other vertebrate NPPs.

Amino Acid Sequence↗
PubMed1996

Partial splenic embolization decreases the serum bilirubin level in patients with hypersplenism following the Kasai procedure for biliary atresia.

BACKGROUND: Partial splenic embolization (PSE) has been used in the palliative treatment of adults and children with hypersplenism. However, there has been no previous report of its use in the treatment of patients with jaundice. The purpose of this study was to investigate the utility of PSE in the treatment of jaundice in patients with biliary atresia and hypersplenism. STUDY DESIGN: Partial splenic embolization was performed in eight patients with biliary atresia and hypersplenism that developed following the Kasai procedure. Seven of them had experienced complete resolution of jaundice postoperatively, but became icteric thereafter. Jaundice remained unchanged in the initial postoperative period in the last patient but subsequently worsened. White blood cell, platelet, and red blood cell counts, hematocrit, and hemoglobin concentrations, and serum concentrations of glutamic-oxaloacetic transaminase, glutamate pyruvate transaminase, alkaline phosphatase, lactate dehydrogenase, albumin, and total bilirubin were evaluated one month before PSE and one, two, three, six, nine, 12, 18, and 24 months after PSE. RESULTS: The total bilirubin concentration decreased in all patients after PSE from 8.6 +/-3.6 mg/dL to 3.0 +/-1.0 mg/dL. This change was noted within three months of PSE, and correlated with an increase in the red blood cell count. CONCLUSIONS: Partial splenic embolization is a useful method for reducing serum bilirubin concentrations in patients with hypersplenism following the Kasai procedure for biliary atresia.

Adolescent↗
PubMed1996

Intrahepatic bile duct stenosis causing intrahepatic calculi formation following excision of a choledochal cyst.

BACKGROUND: Formation of intrahepatic calculi is one of the major late complications after excision of a choledochal cyst. There are few studies, however, that have examined this complication. Generally, an anastomotic stricture is believed to be the main cause of intrahepatic calculi. We report our experience with eight patients who had intrahepatic calculi after excision of a choledochal cyst. STUDY DESIGN: To determine what caused the intrahepatic calculi to form, seven patients underwent cholangioscopy and direct visual inspection during the operation, and one patient underwent percutaneous transhepatic cholangioscopy. Intrahepatic bile was cultured, and calculi were analyzed. RESULTS: Two types of stenoses (membranous and septal) were demonstrated near the hepatic hilum in all patients. Calculi were always located on the hepatic side of the stenoses. No anastomotic strictures were found in the region of the hepaticojejunostomy. The calculi contained mainly calcium bilirubinate. Escherichia coli and Klebsiella pneumoniae were cultured from the bile in all patients. CONCLUSIONS: Stenoses of the intrahepatic bile ducts were demonstrated in all eight patients. The stenoses were considered to be the primary cause of intrahepatic calculi formation after excision of the choledochal cysts.

Adolescent↗
PubMed1996

[Role of tumor marker in the presymptomatic diagnosis of hereditary malignant tumors].

Oncogene is not categorized as a tumor marker in a strict sense, however, cancer related oncogens play an important role as a biomarker in hereditary malignant tumors in a wide sense. Various suppressor oncogenes have been identified in the autosomal dominant hereditary diseases such as APC, in familial adenomatous polyposis, p53 in Li-Fraumeni syndrome and BRACA 1 and 2 in breast cancer. By identifying the mutation site or deletions of germ line, it is possible to make a presymptomatic diagnosis of those hereditary malignant tumors. There is splendid progress in understanding of DNA repair mechanism. Recently, the mismatch repair genes were cloned as a causing gene of HNPCC. There are another group of genes called nucleotide excision repair genes which are causative genes of various autosomal recessive hereditary diseases such as xeroderama pigmentation. Pro and cons of presymptomatic diagnosis of familial adenomatous polyposis were discussed in a series of 72 patients among 42 family trees.

Adenomatous Polyposis Coli↗
PubMed1996

HLA serological and class II genotyping in sarcoidosis patients in Japan.

To investigate the HLA alleles that contribute to the genetic susceptibility to sarcoidosis, HLA serological typing was performed in 75 patients with sarcoidosis and 150 controls using the standard complement-dependent microcytotoxicity method. The genomic DNAs of the 75 patients and 130 of the 150 controls were used to analyze HLA-DRB1, -DQA1, -DQB1 and -DPB1 alleles, utilizing the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Serological typing showed that the frequencies of HLA-DR52, -DR5, -DR6 and -DR8 were significantly increased in the patients compared to the controls. In PCR-RFLP genotyping, the frequencies of the DR52-associated DRB1 alleles (DRB1*11, DRB1*14), DRB1*08, DQA1*0501 and DQB1*0301 were significantly increased in the patients compared to the controls. The frequencies of the DRB1*12 alleles were also increased among the patients, but this increase was not significant. The frequencies of DRB1*0101, DQB1*0501, and DPB*0402 were significantly lower in the patients than in the controls. The significant increases in the frequencies of DQA1*0501 and DQB1*0301 could be due to the linkage disequilibrium between the DR52-associated DRB1 alleles and DQA1*0501 and DQB1*0301 alleles among the Japanese. The significantly increased frequency of the DR8 (DRB1*08) haplotype, which lacks the DRB3 gene encoding DR52 antigen, suggested that the DR5 (DRB1*11), DR6 (DRB1*14) and DR8 (DRB1*08) of the DRB1 alleles may determine the susceptibility to sarcoidosis among the Japanese.

Adolescent↗
PubMed1996

Complete excision of the intrapancreatic portion of choledochal cysts.

BACKGROUND: Cyst excision is the treatment for patients with choledochal cysts. In general, many authors recommend intramural dissection between the outer and inner layers of the cyst or partial excision leaving part of the cyst in the pancreas to avoid pancreatic injury. However, because there are few large series with long-term follow-up periods, it remains unclear how much of the intrapancreatic portion of the cyst should be resected and what resection technique should be used. STUDY DESIGN: During an 18-year period, 104 patients underwent excision of choledochal cysts at our hospitals. Twelve patients had partial excision of the cyst above the pancreas, and 17 had intramural dissection of the intrapancreatic portion. Seventy-five patients underwent complete excision of the intrapancreatic portion of the cyst by our new technique, in which the outer plane of the epicholedochal plexus is dissected, exposing the narrow distal segment connecting the cyst to the pancreatic duct. Our new technique was compared retrospectively with the other two techniques. RESULTS: With our technique, the intrapancreatic cyst could be excised completely in 75 patients without any complications. Blood loss was significantly decreased when our technique was used compared to intramural excision. A pancreatic fistula occurred after intramural excision in one patient, and pancreatic stones formed several years after partial excision and intramural excision in three patients who proved to have residual cystic material in the pancreas. CONCLUSIONS: Our operative technique is safe and effective for the complete excision of the intrapancreatic portion of a choledochal cyst.

Adult↗
PubMed1996

Hydropathy profiles of predicted thyrotropin-releasing hormone precursors are highly conserved despite low similarity of primary structures.

Two types of cDNAs encoding thyrotropin-releasing hormone (TRH) precursors (TRH-A and TRH-B) were amplified from hypothalamic mRNA of sockeye salmon by reverse transcriptase-polymerase chain reaction (RT-PCR). The amplification was achieved using two primers which correspond to TRH progenitor sequence (Lys/Arg-Arg-Gln-His-Pro-Gly-Lys/Arg-Arg). A full length cDNA encoding TRH-A was obtained by 5'- and 3'-RACE methods. It has a length of 1324 base pairs (bp) that contains sequences of 5' and 3' untranslated regions and an open reading frame of 259 codons. The sockeye salmon TRH-A deduced from the nucleotide sequence tandemly contains 8 copies of TRH progenitor sequences. Another cDNA which encodes a part of TRH-B consists of 242 bp, and the sequence homology between TRH-A and -B cDNAs is 90%. The result of Southern blot analysis of sockeye and masu salmon genomic DNAs supported the evidence that there are at least two TRH genes in the salmonid. A RT-PCR analysis of TRH gene expression in various tissues of sockeye salmon showed that strong expression was observed only in the brain. The primary structure of the sockeye salmon TRH-A shares low similarity to those of human, rat and Xenopus TRH precursors (35, 27 and 44%, respectively). However, their hydropathy profiles were almost the same with each other. The profile of sockeye salmon TRH-A showed the presence of two discrete hydrophobic regions, one in the N-terminal region which corresponds to the signal peptide and the other in the C-terminal region. All of the repetitive TRH progenitor sequences are included in three hydrophilic regions easily recognizable. The present results thus suggest that the three-dimensional structures of TRH precursors are highly conserved, although the primary structures of TRH precursors have diverged through the evolutionary pathway of vertebrates.

Amino Acid Sequence↗
PubMed1996

Anatomy and etiology of extrahepatic portal vein obstruction in children leading to bleeding esophageal varices.

BACKGROUND: The cause of extrahepatic portal vein obstruction in childhood is unknown. We investigated the anatomical features of extra hepatic portal vein obstruction to clarify its cause. STUDY DESIGN: We studied portal venous anatomy in 10 patients with extrahepatic portal vein obstruction without hepatic disturbances ranging in age from 1 to 7 years (mean age, 4.2 years) using ultrasonography, portal venography, cholangio-computed tomography, and magnetic resonance imaging. RESULTS: The extrahepatic portal vein was not obliterated, but it crossed over the common bile duct from the left to the right side at the cranial level of the pancreas and ran in a cranial direction along the right side of the common bile duct or coiled itself around the bile duct. Thus, the extrahepatic portal vein formed a tortuous eta-shape. CONCLUSIONS: The portal vein was not obstructed in patients with extrahepatic portal vein obstruction but formed a characteristic eta-shape by coiling itself around the common bile duct, suggesting that extrahepatic portal vein obstruction has an embryological cause.

Bile Ducts, Extrahepatic↗
PubMed1996

Influence of downscatter in simultaneously acquired thallium-201/technetium-99m-PYP SPECT.

UNLABELLED: Simultaneously acquired dual-isotope imaging is a unique and useful approach in SPECT. Photon spillover, however, is a potential limitation of this technique. METHODS: To investigate the degree of 99mTc downscatter into the 201Tl window in patients, simultaneously acquired dual-isotope 201Tl/99mTc-pyrophosphate imaging was performed in 17 patients with acute myocardial infarction (MI). Thallium-201 SPECT imaging was performed first, with a 201Tl photopeak window after the 201Tl injection (early 201Tl images), followed by 99mTc injection and SPECT acquisition using dual-isotope windows (dual 201Tl images). Twenty-four hours after the 99mTc injection, a third set of 201Tl images was obtained (24-hr 201Tl images). Thallium defect size (extent score) and defect severity (severity score) were calculated from these three sets of 201Tl images to quantify the MI. RESULTS: Technetium-99m accumulation of varying intensity was recognized in all patients. Extent scores and severity scores were identical in early 201Tl images and 24-hr 201Tl images. Both scores, however, in the dual 201Tl images were decreased by 36% and 53%, respectively. CONCLUSION: There in a considerable 99mTc downscatter into the 201Tl window, which prevents precise quantification of MI in simultaneously acquired dual-isotope 201Tl/99mTc-pyrophosphate imaging.

Female↗
PubMed1996

HLA class II genotyping of sarcoidosis patients in Hokkaido by PCR-RFLP.

To confirm the significant association of sarcoidosis with HLA-DR5, -DR6, and -DR8 associated DRB1 alleles, in sarcoidosis patients from the eastern Japan (Kanto) area found in our previous study, we used HLA class II genotyping of patients in another region-Hokkaido, in northern Japan. The annual incidence of sarcoidosis in Hokkaido is about three times that of eastern Japan, and Hokkaido has one of the world's highest incidences of this disease. For the HLA class II (HLA-DRB1, -DRB3, -DQA1, -DQB1) genotyping, we used the polymerase chain reaction restriction fragment polymorphism (PCR-RFLP) method with 150 subjects: 40 sarcoidosis patients and 110 healthy controls. The frequencies of DRB1*12, DRB1*14, DRB1*08, DQA1*0501, and DQB1*0301 were significantly increased in the patients, compared with the controls. Our finding of a high frequency of DRB1*08 (which lacks the DRB3 gene encoding the DR52 antigen) in patients living in both eastern Japan and in Hokkaido, confirms that it is the HLA-DRB1 locus, rather than that of the HLA-DRB3, -DQA1, or -DQB1, which determines the susceptibility to sarcoidosis.

Adolescent↗
PubMed1996

Seroepidemiological studies on Silk Road ethnic groups.

To clarify the origin of the Japanese, the Jomom and/or Yayol, we screened for HTLV-1 and -II antibodies among inhabitants of the Silk Road, the Han, Uygur and Kazaks. We also screened for HIV, HBV, and HCV. The HTLV-I, -II, HIV, and HCV antibody tests were uniformly negative in all the studied groups. In contrast, a significantly higher incidence of HBs antigen was observed in all the groups tested (Northern Han: 11.9%, Uygur: 6.0%, Kazak: 9.1%). These results indicate that these ethnic groups are not the origin of the indigenous Japanese (the Jomon), and that HBV is prevalent in the various groups along the Silk Road.

Antigens, Viral↗
PubMed1995

Different effects of isoproterenol and dihydroouabain on cardiac Ca2+ transients.

Cytosolic fura-2 Ca2+ transient signals (TCa) and the left ventricular pressure or contraction of myocardium under the positive inotropic effects of the beta-adrenoceptor agonist, isoproterenol, and the cardiac glycoside, dihydroouabain, were measured simultaneously and the results were compared. TCa was observed preceding the onset of force development and showed a steeper rise and slower decay than did the contraction curve of papillary muscle. Isoproterenol increased the steepness and the amplitude of TCa, reflecting the speed and peak force of contraction, and clearly biphasic TCa were observed with biphasic contractions developed at low frequency. Ryanodine reduced not only the early component of the contraction but also TCa, without affecting the diastolic Ca2+ level. These effects of isoproterenol were attributed to the enhanced uptake of Ca2+ by the sarcoplasmic reticulum. In contrast, dihydroouabain elevated the Ca2+ level at diastole without any change in the amplitude of TCa, suggesting that dihydroouabain inhibits the membrane Na pump thereby increasing the intracellular Ca2+ via Na(+)-Ca2+ exchange. Furthermore, a comparison of the time course of the isometric twitch curve with that of TCa in rested state contraction indicated that there are distinct differences between the mechanisms of the positive inotropic effects of isoproterenol and of dihydroouabain.

Adrenergic beta-Agonists↗
PubMed1995

Effects of Ringer's acetate solution during transient hepatic inflow occlusion in rabbits.

This study aimed to clarify the difference in the effects of sodium acetate and sodium lactate administration on hepatic energy metabolism during hepatic warm ischemia and reperfusion. In the first experiment, Ringer's acetate (AR) or Ringer's lactate (LR) solutions were administered intravenously during 20 min of hepatic inflow occlusion in rabbits. Blood gas analyses and measurements of blood pressure, pyruvate, lactate, and ketone body concentrations in arterial blood were performed until 30 min of reperfusion. Hepatic tissue adenine nucleotide concentrations were determined at the end of the experiment. With AR administration, the plasma pyruvate level and the ratio of pyruvate to lactate were significantly elevated during reperfusion. Hepatic energy charge at 30 min of reperfusion improved significantly (P < 0.001) with AR compared with LR administration. Plasma ketone body concentrations decreased markedly with LR administration, but were maintained with AR administration. In the second experiment, intravenous administration of AR or LR, hepatic ischemia, and reperfusion were similarly performed in rabbits. Ketone body concentrations were determined in arterial and vena cava blood at 0 min, 20 min of inflow occlusion, and 30 min of reperfusion. With AR administration, a large arteriovenous difference in ketone body concentrations was observed, indicating utilization in the peripheral tissues. With LR administration, no arteriovenous difference was observed. Availability of energy substrate in peripheral tissues by administration of AR is thought to decrease the metabolic load to the liver and to improve hepatic energy status during reperfusion.

Adenine Nucleotides↗
PubMed1995

Correlation between the number of melanosomes, tyrosinase mRNA levels, and tyrosinase activity in cultured murine melanoma cells in response to various melanogenesis regulatory agents.

Tyrosinase is the rate limiting enzyme critically associated with melanin synthesis. The melanosomes are specialized membrane-bound organelles within melanocytic cells in which melanin polymers are ultimately deposited. To determine whether tyrosinase correlates with the number of melanosomes, we examined the relationship between tyrosinase activity, tyrosinase mRNA levels, and the number of melanosomes in B16 murine melanoma cells, using melanogenesis regulatory agents. 12-O-Tetradecanoylphorbol-13-acetate (TPA) or linoleic acid decreased tyrosinase activity, while dibutyryl cyclic adenosine monophosphate (dbcAMP) or palmitic acid increased it. The tyrosinase mRNA levels were not always correlated with tyrosinase activity, i.e., TPA down-regulated, dbcAMP upregulated, while linoleic acid or palmitic acid did not alter the message levels, indicating that fatty acid regulation of melanogenesis was due to post-transcriptional events. The number of melanosomes changed when agents which modulate the tyrosinase gene expression were added, since TPA decreased, dbcAMP increased, and linoleic acid or palmitic acid did not alter their number. These results suggest that the number of melanosomes changed in relation to tyrosinase mRNA level but not to tyrosinase activity in response to melanogenesis regulatory agents.

Animals↗
PubMed1995

Laparoscopic cholecystectomy with an ultrasound surgical aspirator.

Laparoscopic cholecystectomy using an ultrasound surgical aspirator has been performed in our department since March 1991. The horn cover was altered in order to be inserted through a trocar 10 mm in diameter. The main purpose of this device is to explore Calot's triangle by fragmentation and aspiration of the fatty tissue without damaging the nerves, vessels, and cystic duct. First the serosa of the Calot's triangle is cut via electrocautery with the sharp-angle hook dissector we designed. Then the cystic duct and cystic artery are efficiently exposed by the ultrasound surgical aspirator. This procedure is perfectly adapted for laparoscopic cholecystectomy. We obtained favorable results with the ultrasound surgical aspirator in 135 cases including 40 cases with a negative gallbladder, as evaluated by endoscopic retrograde cholangiography. In conclusion, the ultrasound surgical aspirator is suitable for skeletonizing the cystic duct and cystic artery, and the procedure is perfectly safe.

Cholecystectomy, Laparoscopic↗