Search PubMed⌕ Search

Biomedical subjects

M Tanji

Publications and source records attributed to M Tanji.

At least 37 records · Page 2Linked to original sources

[Two cases of atrial septal defect with absence of right superior vena cava and persistent left superior vena cava].

Two women (16-year-old, 54-year-old) of atrial septal defect with absence of right superior vena cava and persistent left superior vena cava were successfully operated on. Electrocardiographic findings show coronary sinus rhythm and atrial fibrillation. When we closed atrial septal defect cannulated to persistent left superior vena cava via the coronary sinus directly, sick sinus syndrome was not appeared postoperatively.

Adolescent↗

Purification, characterization, and amino acid sequences of pepsinogens and pepsins from the esophageal mucosa of bullfrog (Rana catesbeiana)

Two pepsinogens (pepsinogens 1 and 2) were purified from the esophageal mucosa of the bullfrog (Rana catesbeiana), and their molecular weights were determined to be 40,100 and 39,200, respectively, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The NH2-terminal 70-residue sequences of both pepsinogens are the same, including the 36-residue activation segment. Furthermore, a cDNA clone encoding frog pepsinogen was obtained and sequenced, which permitted deduction of the complete amino acid sequence (368 residues) of one of the pepsinogen isozymogens. The calculated molecular weight of the protein (40,034) coincided well with the values obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These results are incompatible with the previous report (Shugerman R. P., Hirschowitz, B. I., Bhown, A. S., Schrohenloher, R. E., and Spenney, J. G. (1982) J. Biol. Chem. 257, 795-798) that the major pepsinogen isolated from the bullfrog esophageal gland is a unique "mini" pepsinogen with a molecular weight of approximately 32,000-34,000. The two pepsinogens were immunologically indistinguishable from each other and related to human pepsinogen C. The deduced amino acid sequence was also more homologous with those of pepsinogens C than those of pepsinogens A and prochymosin. These results indicate that the frog pepsinogens belong to the pepsinogen C group. They were both glycoproteins, and therefore, this is the first finding of carbohydrate-containing pepsinogens C. Both pepsinogens were activated to pepsins in the same manner by an apparent one-step mechanism. The resulting pepsins were enzymatically indistinguishable from each other, and their properties resembled those of tuna pepsins.

Amino Acid Sequence↗

The primary structure of Aspergillus niger acid proteinase A.

The complete amino acid sequence of the acid proteinase A, a non-pepsin type acid proteinase from the fungus Aspergillus niger var. macrosporus, was determined by protein sequencing. The enzyme was first dissociated at pH 8.5 into a light (L) chain and a heavy (H) chain, and the L chain was sequenced completely. Further sequencing was performed with the reduced and pyridylethylated or aminoethylated derivative of the whole protein, using peptides obtained by digestions with Staphylococcus aureus V8 protease, trypsin, chymotrypsin, and lysylendopeptidase. The location of the two disulfide bonds was determined by analysis of cystine-containing peptides obtained from a chymotryptic digest of the unmodified protein. These results established that the protein consists of a 39-residue L chain and a 173-residue H chain that associate noncovalently to form the native enzyme of 212 residues (Mr 22,265). This is, to our knowledge, the first time that such a protein with a rather short peptide chain associated noncovalently has been found. No sequence homology is found with other acid or aspartic proteinases, except for Scytalidium lignicolum acid proteinase B, an enzyme unrelated to pepsin by sequence, which has about 50% identity with the present enzyme. These two enzymes, however, are remarkably different from each other in some structural features.

Amino Acid Sequence↗

Occurrence of cathepsin D isozymes with different specificities in monkey skeletal muscle.

Cathepsin D was highly purified from the skeletal muscle of Japanese monkey (Macaca fuscata fuscata) by a procedure including affinity chromatography on concanavalin A-Sepharose and pepstatin-Sepharose, and then resolved into ten isozymes (A through J) by isoelectric focusing. When examined for specificity toward oxidized insulin B chain, isozyme A was highly specific and cleaved exclusively the Leu15-Tyr16 bond, whereas isozyme F was less specific, cleaving the Leu15-Tyr16 and Glu13-Ala14 bonds, with slower cleavages at several other bonds. These results demonstrate for the first time the occurrence of isozymes with different specificities among cathepsin D isozymes obtained from a single source.

Amino Acid Sequence↗

Methylation and expression of human pepsinogen genes in normal tissues and their alteration in stomach cancer.

In normal human tissues, pepsinogen A mRNA was expressed only in the fundic mucosa of the stomach, whereas pepsinogen C mRNA was expressed in all regions of the stomach mucosa and also in the proximal duodenal mucosa. The distributions of these mRNAs were consistent with those of pepsinogens A and C in the gastroduodenal mucosa. Methylation analysis of DNAs from normal tissues with methylation-sensitive restriction enzymes, HpaII and HhaI, revealed that pepsinogen A and C genes are hypomethylated in tissues producing pepsinogens A and C, suggesting a role of DNA methylation in the regulation of the differential expression of the genes for the two human pepsinogens during normal differentiation. In stomach cancer tissues and cancer cell lines, the expressions of the pepsinogen genes were decreased or lost, in good accordance with their pepsinogen productions. No gross structural changes of the pepsinogen genes were observed in these cancers, but the methylation patterns of the pepsinogen genes were found to be altered in different ways in different cancers. The functional significance of the altered methylation is unknown; however, these results suggest that considerable heterogeneity of the methylation patterns occurs in human stomach cancers.

Blotting, Northern↗

[A case of ruptured aneurysm of Valsalva sinus into right atrium with peculiar findings on aortography].

A 24-year-old man with ruptured aneurysm of sinus of Valsalva into the right atrium originating from the noncoronary sinus is presented. On aortography through the ascending aorta the right atrium in systolic phase and the right ventricle in diastolic phase were opacified. We considered ruptured aneurysm like a streamer (wind sock) entered into the right ventricle in diastolic phase and into the right atrium in systolic phase. Post-aneurysmectomy course was uneventful, and radiographic examination revealed complete repair of the aneurysm.

Adult↗

[A case report of perforated aneurysm of mitral valve with aortic regurgitation].

The patient was a 71-year-old male who complained of palpitation and tachycardia. The echocardiogram showed a bulging of the anterior mitral valve leaflet toward the left atrium that persisted throughout cardiac cycle. The cine angiogram showed deformity of the anterior mitral valve leaflet with severe mitral regurgitation and mild aortic regurgitation. At operation, a perforated aneurysm was recognized at the anterior mitral valve leaflet without thrombus and vegetation. The size of aneurysm was 40 x 25 x 25 mm. The patient underwent MVR + AVR, and the postoperative course was uneventful. Pathological examination of the anterior mitral valve leaflet revealed scar-like fibrosis and old inflammatory change. It was judged a true aneurysm of mitral valve, because the structure of endocardium was kept.

Aged↗

Hydrocortisone-induced enhancement of expression and changes in methylation of pepsinogen genes in stomach mucosa of the developing rat.

Administration of hydrocortisone to infant rats caused a precocious increase in levels of mucosal pepsinogen and its mRNA together with morphological maturation of pepsinogen-producing cells. The increase in levels of pepsinogen mRNA was induced rapidly and was associated with increase in levels of its precursors, suggesting transcriptional regulation of pepsinogen genes by hydrocortisone. Methylation analysis with the methylation-sensitive restriction enzymes, HpaII and HhaI, revealed that hydrocortisone also induced sequential demethylation changes of CCGG and GCGC sites in and around pepsinogen genes. Most of these changes occurred after increases in transcription of the genes and did not appear to play a causal role in gene activation. Superficially, the observed demethylations corresponded to the sequential processes of morphological maturation of pepsinogen-producing cells. Thus, these changes in methylation are probably linked to hydrocortisone-induced differentiation of pepsinogen-producing cells and may reflect the mechanism in vivo for the maturation of pepsinogen genes.

Animals↗

[Report of five cases of major surgery during anticoagulant therapy after prosthetic valve replacement].

The major surgery for gastroduodenal ulcer, gastric cancer, esophageal cancer, and mediastinal tumor, were performed on 5 patients during anticoagulant therapy after prosthetic valve replacement. In the postoperative management, Dipyridamole (30 mg/day) was given in case 1, Heparin sodium (24,000 mu/day) in case 2, 3, and Gabexate Mesilate in case 4, 5. Postoperative course was uneventful in case 1, 3, 4, 5, intratracheal bleeding was recognized on the 3rd postoperative day and treated by reducing of heparin dose in case 2. Gabexate Mesilate was thought to be effective and free from complication in case 4, 5.

Adult↗

[Disseminated intravascular coagulation (DIC) after artificial valve replacement: especially tricuspid regurgitation].

To investigate disseminated intravascular coagulation (DIC) after valve replacement, we studied DIC score in 80 patients with combined cardiac valvular disease. Thirty-three patients with (TR group) and 47 patients without (control group) tricuspid regurgitation were compared. 1) TR group, that included patients with severe cases, showed a significantly longer operative time and greater bleeding volume (p less than 0.01). 2) The DIC score was significantly higher in TR group. Administration of gabexate mesilate to patients with DIC improved their platelet counts. These results indicate that patients with combined cardiac valvular disease with tricuspid regurgitation have a hemorrhagic tendency and are subject to DIC. Administration of gabexate mesilate is useful for DIC.

Adult↗

[Senile alteration of hemodynamics in surgery of abdominal aneurysm].

Hemodynamic measurements were performed before, during and after surgery of aneurysmal patients. Fifty non-ruptured infrarenal aneurysmal patients undergoing elective aortic reconstructions were studied. Patients who had no evidence of heart disease were divided into two groups by age. The older group consisted of 22 patients older than 70 years of age, and the younger group consisted of 28 patients younger than 70 years. The results may be summarized as follows: (1) Hemodynamics before surgery (volume loaded test): For 500 ml albumin infusion within 30 minutes, cardiac indices of the older group kept below 4.0 l/min/m2, whereas in the younger group there was an increase from 3.66 to 4.42 l/min/m2. (2) Hemodynamics during surgery: Peripheral resistance increased by cross-clamping of the aorta, and decreased after removal of the aorta, and decreased after removal of the cross clamp in both groups. Cardiac indices dropped during cross-clamping of the aorta. The older group dropped more noticeably compared with the younger group, for instance, at one minute after cross-clamping, the older group was 2.04 +/- 0.56, and the younger group was 2.44 +/- 0.56 l/min/m2. Mean pulmonary wedge pressure increased gradually during surgery in both groups. (3) Hemodynamics after surgery: The older group kept lower cardiac indices compared with the younger group, but not so noticeably. These results indicated that older patients have low cardiac function for preload and afterload change. We will be confronted by an increasing number of older patients in the near future. Hemodynamic managements of aortic reconstructions in the elderly might become important.

Age Factors↗

Difference of activation processes and structure of activation peptides in human pepsinogens A and progastricsin.

The activation processes of two human pepsinogens A (pepsinogens 3 and 5) and progastricsin were compared with special attention to pepsinogens 3 and 5. Each zymogen was converted to pepsin in a stepwise manner through intermediate forms. In pepsinogens A, the major cleavage site was the Leu23-Lys24 bond and this cleavage was suggested to occur intramolecularly. When each of the pepsins A was added to the corresponding pepsinogen A exogenously, the latter was rapidly converted to pepsin, releasing the 47-residue intact activation segment. In this case, the Leu47-Val48 bond connecting the activation segment with the pepsin moiety was cleaved by an intermolecular reaction. On the other hand, when the pepsinogen A-pepstatin complex was attacked by each corresponding pepsin A added exogenously, significant cleavage by an intermolecular reaction occurred at the Asp25-Phe26 bond, generating the Phe26-intermediate form. These shifts of the cleavage sites in pepsinogens A depending on the activation conditions are likely to correlate with the conformation of the activation segment. These results can be explained consistently in terms of a proposed molecular model of activation.

Amino Acid Sequence↗

A comparative study on the NH2-terminal amino acid sequences and some other properties of six isozymic forms of human pepsinogens and pepsins.

Six pepsinogen isozymogens, including five forms of pepsinogen A (PGA) and an apparently single form of pepsinogen C (PGC), were isolated simultaneously from the purified total pepsinogen fraction of human gastric mucosa by fast protein liquid chromatography on a Mono Q column, and their NH2-terminal amino acid sequences and some other properties were compared. Upon activation at pH 2.0, all the isozymogens were converted to the corresponding pepsins in a stepwise manner through intermediate forms. The activation rates and the cleavage sites in the activation peptide segment to generate intermediate forms were significantly different among the isozymogens. The NH2-terminal 85-residue amino acid sequences of these isozymogens were determined, including the sequences of the activation peptide segments and the NH2-terminal regions of the corresponding pepsins. Differences in amino acid sequence were found at positions 43 and 77 among the pepsinogen A isozymogens; the residue at position 43 was Lys in PGA-5, PGA-4, and PGA-3a, and Glu in PGA-3 and PGA-2, and the residue at position 77 was Leu in PGA-5 and PGA-4 and Val in PGA-3 and PGA-2. Phosphate was not found in any of the isozymogens. The corresponding pepsins also showed significant variations in properties such as specific activities toward synthetic and protein substrates, pH dependence of activity, susceptibility to various inhibitors, and thermal and alkaline stabilities.

Amino Acid Sequence↗

[A case report of mycotic false aortic aneurysm associated with aortic regurgitation].

The patient was 63-year-old man, who underwent patch closure of VSP 37 days after onset. LVAD was required for weaning from CPB. Mediastinitis occurred after LVAD was removed. The mediastinum was irrigated using diluted antibiotics through the retrosternal drain. He discharged on 79th day postoperatively. False aortic aneurysm and marked AR was pointed out by cineangiography and enhanced CT scan two years after operation. AVR was performed through right thoracotomy, because false aortic aneurysm invaded the sternum. The aneurysmal wall was repaired with patch. Postoperatively, peritoneal dialysis was performed for two days. Flail chest made difficult weaning from the respirator. He died 11 days postoperatively due to respiratory failure. There remains the possibility that mediastinitis resulted in false aortic aneurysm and AR. It was esseutial to remove the foreign materials placed on the aorta for eradication of infection.

Aneurysm, Infected↗

[Cardiac surgery of tetralogy of Fallot associated with DiGeorge syndrome: a case report].

A case of 7-year-old boy with tetralogy of Fallot associated with DiGeorge syndrome was reported. He had been diagnosed as cardio-facial syndrome with hypoparathyroidism because of hypocalcemia, convulsion, cardiac defect and the characteristic face. But immunologic study showed hypofunction of cellular immunity and cardiac catheterization and angiogram revealed the Tetralogy of Fallot. So we diagnosed as DiGeorge syndrome and performed operation. The thymus was not found and we close the ventricular defect with patch and reconstructed right ventricular outflow tract with transannular patch. We often measured serum ionized calcium level and corrected with calcium gluconate intravenously. Peritoneal dialysis was done due to oliguria and much inotropic support was necessary.

Child↗

[Pulmonary artery aneurysm-like associated with pulmonary stenosis].

A 55-year old man had complained shortness of breathing and an abnormal shadow at left hilus region had been pointed out on the chest X-ray film. Right heart catheterization and right ventriculography revealed pulmonary valve stenosis with pulmonary artery aneurysm-like. Utilizing cardiopulmonary bypass, aneurysmorrhaphy and valvotomy was performed. Postoperative course was good and he was discharged on the 29th postoperative day. It is considered that mild post-stenotic dilatation of pulmonary trunk due to pulmonary valvular stenosis might develop into the aneurysmal change because of some congenital structural deficiency in the pulmonary arterial wall.

Aneurysm↗

[A case report of aneurysm of the sinus of Valsalva due to infectious endocarditis with ASR].

A case (56 year-old, female) of the aneurysm of sinus of Valsalva due to infectious endocarditis with aortic stenosis and regurgitation was described. The patient was successfully operated upon by patch closure of the orifice of the aneurysm and aortic valve replacement with Medtronic Hall 23A. Post operative course was uneventful and discharged from the hospital at 37 post operative days in good condition.

Aortic Aneurysm↗