Biomedical subjects

S Yamaki

Publications and source records attributed to S Yamaki.

At least 19 recordsLinked to original sources

PubMed1999

Structural relationship of lambda-type light chains with AL amyloidosis.

Three human amyloidogenic Bence Jones proteins, NIG76 VlambdaII, NIG204 VlambdaI, and NIG250 VlambdaV, were characterized. In a comparative study, three amino acids, Ser-25a, Thr-68, and Val-95, were found to be common to amyloidogenic proteins of the VlambdaII subgroup. NIG204 had an insertion of Pro residue following position 30 (30a). Proteins having an insertion at this position are invariantly amyloidogenic. NIG250 had a characteristic VlambdaV VL domain, with Mcg+ and KERN+ CL domain isotypes. Following the protein DEL, this is the second example of this subgroup. No common residue is found in the other subgroup proteins but unique substitutions do occur. It would seem that any substitution that causes an alteration in the protein conformation may lead to its being more prone to association with the amyloid processes.

Amino Acid Sequence↗

PubMed1999

Progressive pulmonary vascular disease after pulmonary artery banding and total correction in a case of ventricular septal defect and pulmonary hypertension.

A 7-month-old infant with ventricular septal defect and pulmonary hypertension underwent pulmonary artery banding, which resulted in a decrease in the pulmonary arterial peak pressure from 102 to 54 mmHg. Lung biopsy findings showed at most an early grade 3 Heath-Edwards classification, and an index of pulmonary vascular disease of 1.4, both of which indicated operability for total correction. Small pulmonary arteries less than 100 microns in diameter, however, showed marked hydropic changes in the medial smooth muscle cells. Total correction was performed at the age of 2 years, but the pulmonary arterial pressure failed to decrease. A lung biopsy taken just after the closure of the ventricular septal defect contraindicated operability due to progressive pulmonary vascular disease at a grade 6 Heath-Edwards classification and an index of pulmonary vascular disease of 2.4. The patient died at 8 months after the operation, and an autopsy revealed still more advanced pulmonary vascular disease at a grade 6 Heath-Edwards classification and an index of pulmonary vascular disease of 2.8. The pathogenesis of arterial changes is discussed.

Disease Progression↗

PubMed1999

Vacuolar H(+)-pyrophosphatase purified from pear fruit.

A vacuolar H(+)-translocating inorganic pyrophosphatase was purified from pear fruit through selective detergent treatments, Superose 6 and Mono Q column chromatography. The specific activity of the purified enzyme was 850 mumol h-1 mg protein-1. The Mr of V-PPase was 66 kDa by SDS-PAGE and the polypeptide cross-reacted with the antiserum against V-PPase of mung bean. The purified V-PPase was stimulated by potassium and inhibited by calcium and N, N'-dicyclohexylcarbodiimide.

Blotting, Western↗

PubMed1999

Identification and cDNA cloning of a protein abundantly expressed during apple fruit development.

A 60 kDa protein (MF-60) abundantly appearing in matured apple fruit was detected by SDS-PAGE of the soluble protein. It was partially purified through Butyl-Toyopearl and DEAE-cellulose. Its partial amino acid sequences were determined to isolate a full-length cDNA. MF-60 cDNA (mf-60) consisting of 1,825 bp containing an open reading frame of 1,524 bp and encoding a 54.2 kDa polypeptide. The deduced polypeptide of mf-60 has 81.1% identity to turgor-responsive protein 26 g from wilted garden pea shoot. Northern blot and Western blot analyses showed that the levels of the protein and the transcript of MF-60 changed in parallel through the developmental season; they were very low in young fruit at 36 DAF and 60 DAF, started to increase at 85 DAF, and then remained at a higher level from 114 DAF to 176 DAF. These results suggested that MF-60 functions are connected with fruit development but not with the fruit ripening induced by ethylene.

Amino Acid Sequence↗

PubMed1998

[Repair of complete atrioventricular septal defect with severe pulmonary hypertension--effect of re-pulmonary artery banding and analysis of lung biopsy: a case report].

We report a case complete atrioventricular defect with severe pulmonary hypertension. The patient was a girl aged 2 years and 6 months with Down's syndrome who had undergone pulmonary artery banding (PAB) 2 years previously. Postoperative catheterization after PAB showed severe pulmonary hypertension. Pulmonary resistance values were 9.3 and 7.3 units at 1 year and 5 months and 1 year and 9 months respectively. We performed re-PAB and lung biopsy when the patient was 2 years and 6 months old. The biopsy specimen at re-PAB classified as Heath-Edwards grade 3 and had an IPVD score of 1.7, indicating tolerance to radical operation. Six months after re-PAB, pulmonary vascular resistance decreased a level at which radical operation could be performed safely. Radical operation was performed 1 year and 4 months after re-PAB. The post operative course was uneventful, and pulmonary hypertensive crisis did not occur. The lung biopsy at the final operation was classified as Heath-Edwards grade 3, had an IPVD score of 1.1, and showed improvement when compared with the pathological findings at re-PAB.

Biopsy↗

PubMed1998

Surgical indication for congenital heart disease with extremely thickened media of small pulmonary arteries.

BACKGROUND: Nineteen patients (mean age, 7.6 months) with a percent wall thickness of more than 33% in the small pulmonary arteries were found to have extremely thickened media. Based on our findings, a criterion of operative indication is proposed. METHODS: The percentage of extremely thickened media of small pulmonary arteries for all pulmonary arteries was determined on microscopic lung sections and was introduced as an index for operative indication. RESULTS: Operative repair was performed in 16 patients: 9 died intraoperatively and 7 survived more than 12 months. In 4 of 5 patients that had pulmonary artery banding, medial hypertrophy remained despite pulmonary artery banding. Operative repair also had no positive effect. In operative and late deaths and in survivors without a decrease of pulmonary arterial pressure, the percentage of extremely thickened media of small pulmonary arteries was shown to be more than 10%, whereas in 5 survivors and 1 operative death with a significant postoperative decrease of pulmonary arterial pressure, the value was less than 7%. CONCLUSIONS: If a patient has less than 7% of small pulmonary arteries with extremely thickened media, operative repair is likely to be effective. When the value is higher than 10%, not only operative repair but also pulmonary artery banding cannot be recommended because of ineffectiveness and hazard.

Blood Pressure↗

PubMed1998

Inoperable pulmonary vascular disease in infants with congenital heart disease.

BACKGROUND: Among 120 infants less than 12 months of age who had lung biopsy and autopsy, 20 were inoperable because of severe irreversible pulmonary vascular disease. METHODS: The infants were classified into three groups. Group 1 comprised 6 patients who showed complete obstruction of the small pulmonary arterial lumen and atrophy of the peripheral arterial media and who were considered to have absolute operative contraindications. Group 2 comprised 6 patients who had no pathologic findings of absolute operative contraindication and had an index of pulmonary vascular disease of more than 2.2. They were isolated as having advanced plexogenic pulmonary arteriopathy. Group 3 comprised 8 patients who had extremely thickened media of small pulmonary arteries, with abnormally thickened media extending into the small peripheral arteries characterized by extremely narrow lumina and medial thickness exceeding luminal diameter. RESULTS: Six of the 9 patients in whom operative repair was abandoned on the basis of preoperative or intraoperative lung biopsy are still alive. Of the 11 patients who underwent operation without biopsy, none survived. CONCLUSIONS: Preoperative or intraoperative lung biopsy and assessment of arteriopathy based on the above criteria are recommended in all patients in whom fatal pulmonary vascular disease is suspected.

Atrophy↗

PubMed1998

Cloning of NAD-dependent sorbitol dehydrogenase from apple fruit and gene expression.

Partial amino acid sequences of NAD-dependent sorbitol dehydrogenase (NAD-SDH) were used to identify a full-length cDNA from apple fruit. This clone consisted of 1,433 bp containing an open reading frame of 1,137 bp that could code for a polypeptide with 379 amino acids. To our knowledge, this is the first report about cloning of NAD-SDH cDNA from a plant source. The deduced amino acids from cDNA revealed 43.7% identity to human NAD-SDH. The activity of this enzyme to convert sorbitol to fructose with the reduction of NAD was certified by the fusion protein of this clone expressed in Escherichia coli. Northern blot analysis showed that the mRNA was expressed in matured apple fruit.

Amino Acid Sequence↗

PubMed1997

Pulmonary hypertension caused by medial hypertrophy associated with aortic stenosis and preductal coarctation.

A 7-month-old female infant with aortic stenosis, preductal coarctation, and pulmonary hypertension underwent operation. Intraoperative lung biopsy revealed marked medial hypertrophy of the pulmonary arterioles. This histopathology is compatible with persistent pulmonary hypertension in the newborn. She is alive about 5 years after the operation, but pulmonary hypertension remains. The pathogenesis is discussed.

Aortic Coarctation↗

PubMed1997

Changes in H(+)-pumps and a tonoplast intrinsic protein of vacuolar membranes during the development of pear fruit.

Vacuolar H(+)-ATPase (V-ATPase) was purified from pear fruit and antibodies were raised against the subunits of 55 and 33 kDa. Antibodies against mung bean H(+)-pyrophosphatase (V-PPase) and radish VM23, which is a tonoplast intrinsic protein (TIP) and a water channel, cross-reacted with the vacuolar membrane proteins of pear fruit. To clarify the roles of these proteins in development of pear fruit, we determined their levels relative to the total amount of protein by immunoblot analysis. The levels of subunits of the V-ATPase increased with fruit development. By contrast, the level of V-PPase was particularly high at the cell-division stage and remained almost the same at other stages. The changes in the activities of V-ATPase and V-PPase corresponded to those in their protein levels. The ratio of V-PPase activity to V-ATPase activity indicated that V-PPase is a major H(+)-pump of the vacuolar membranes of young fruit and that the contribution of V-ATPase increases with fruit development, finally, V-ATPase becomes the major H(+)-pump during the later stages of fruit development. The level of a protein analogous to VM23 (VM23P) was especially high during the active cell-expansion stage in young fruit, and VM23P might, therefore, play an important role in the rapid expansion of cells as a vacuolar water channel. Our results show that the levels of V-ATPase, V-PPase and VM23P change differently and reflect the roles of the respective protein in the development of pear fruit.

Adenosine Triphosphatases↗

PubMed1997

Microatelectasis in patients with secundum atrial septal defect and its relation to pulmonary hypertension.

In patients with secundum atrial septal defect, pulmonary hypertension appears to be attributable to microatelectasis of the lung. To confirm this hypothesis, pulmonary arteries in surgical biopsy specimens from 72 patients with atrial septal defect and pulmonary hypertension were subjected to morphometric examination. Thirty eight of the 72 patients (53%) were found to have microatelectasis of the lung, which suggests that an even higher frequency would have been found if the entire organ had been examined. Atelectatic changes were found in 21 of 39 patients with plexogenic pulmonary arteriopathy (54%), 8 of 15 with musculoelastosis (53%), and 9 of 13 with both of these lesions (69%). No such changes were observed in 5 patients with atrial septal defect who showed thromboembolism-type lesions of the pulmonary arteries. On the other hand, microatelectasis was not observed in another 5 patients with atrial septal defect who did not exhibit pulmonary hypertension. The medial smooth muscles of pulmonary arteries in atelectatic areas were thicker (16.4 +/- 4.0 microns) than those in non-atelectatic areas (10.3 +/- 3.3 microns). The index of pulmonary vascular disease was not significantly different between atelectatic (2.0 +/- 0.6) and non-atelectatic areas (1.9 +/- 0.5). We conclude that in microatelectatic areas, which may tend to develop after respiratory infections in patients with atrial septal defect, hypoxic vasoconstriction of the small pulmonary arteries is liable to occur, which causes hypertrophy of the media. This is likely to lead to the elevation of pulmonary arterial pressure and sustained pulmonary hypertension.

Adolescent↗

PubMed1997

Microangiopathic hemolytic anemia and thrombocytopenia in a child with atrial septal defect and pulmonary hypertension.

Microangiopathic hemolytic anemia and thrombocytopenia have been reported in patients with primary pulmonary hypertension, but not in patients with congenital heart disease even if accompanied with pulmonary hypertension. We present a 7-year-old boy with atrial septal defect and pulmonary hypertension who developed microangiopathic hemolysis and thrombocytopenia. Microangiopathic hemolytic anemia and thrombocytopenia should be remarked as a complication in patients with congenital heart disease.

Anemia, Hemolytic↗

PubMed1997

Different grades of medial hypertrophy and intimal changes in small pulmonary arteries among various types of congenital heart disease with pulmonary hypertension.

Morphometric analysis of small pulmonary arterial changes was performed in three patients with different congenital heart disease with pulmonary hypertension: congenital mitral stenosis (MS), ventricular septal defect (VSD) and transposition of the great arteries (TGA). The material was biopsy or autopsy lung specimens, all having the same degree of elevated pulmonary arterial pressure. Medial thickness was determined by the method of Suwa and Takahashi, and the degree of intimal changes was quantified using the index of pulmonary vascular disease (IPVD) by Yamaki and Tezuka. It was demonstrated that the medial thickening of the small pulmonary arteries was the strongest in the patient with congenital MS, moderate in VSD, and the weakest in TGA, with statistically significant differences between each pair of these three conditions. Interestingly, the order of severity for intimal changes was reversed: it was the severest in TGA and the mildest in congenital MS. We surmise that in patients with TGA, medial hypertrophy is suppressed by sustained vasodilation resulting from the high oxygen saturation of pulmonary arterial blood, while in congenital MS, the media undergoes the severest hypertrophy because of the low oxygen saturation. We also conclude that in TGA intimal changes readily develop in the presence of attenuated media, while in congenital MS, the thickened media seems to prevent intimal changes. From a clinical viewpoint, these results urge us to recommend early surgical intervention in TGA and VSD where severe intimal changes can develop in the absence of extreme medial thickening. It may not be appropriate to extend operation on patients with congenital MS, since strongly thickened media can trigger vasospasms and medial necrosis.

Adolescent↗

PubMed1997

[Pulmonary thromboembolism associated with antiphospholipid syndrome in scleroderma].

A 51-year-old woman was referred to our hospital with dyspnea. Chest roentgenogram on admission showed dilation of the pulmonary arteries and hyperlucency in the lung fields. An ultrasonic cardiographic examination showed that the right atrium and ventricle were dilated. Pulmonary thromboembolism due to left popliteal vein thrombosis was diagnosed by perfusion scintigram of the lung, which showed multiple wedge-shaped defects, and by digital subtraction angiogram, which showed a filing defect in the left popliteal vein. Antiphospholipid syndrome was diagnosed after IgG anticardiolipin antibody was defected. Scleroderma was subsequently diagnosed because the patient exhibited Raynaud's phenomenon and proximal scleroderma. Although closely associated with lupus erythematosus and other lupus variants, antiphospholipid syndrome has not been recognized as a common complication of scleroderma. This is the first report of a patient with pulmonary thromboembolism associated with antiphospholipid syndrome and scleroderma.

Antibodies, Anticardiolipin↗

PubMed1996

High-performance liquid chromatography of peptides on a microspherical carbon column.

The properties of a microspherical carbon column for the separation of peptides and proteins are described. One hundred and thirty-three peptides, with from 1 to 148 amino acid residues, were applied on a carbon column and eluted with a linear gradient of acetonitrile [10-70% (v/v), 30 min] in 0.1% (v/v) trifluoroacetic acid solution. The elution behaviour of the peptides on the carbon column and on an octadecylsilica (ODS) column were compared under the same elution conditions. Relationships between the logarithm of the hydrophobicity of peptides and their capacity factors were approximately linear on both columns, but some exceptions were observed with peptides with aromatic residues, indicating stronger adsorption on the carbon than on the ODS column. These results suggest that the major factor for the separation of peptides on both the carbon and ODS columns is hydrophobic interactions. The stronger adsorption of aromatic side-chains in peptides on the carbon column could be understood by an interaction based on the aromatic or graphitic nature of the surface of the microspherical carbon packings.

Amino Acid Sequence↗

PubMed1996

Reversed-phase liquid chromatography on a microspherical carbon column at high temperature.

The chromatographic conditions for the use of a spherical carbon column at high temperatures up to 160 degrees C are described. The column heating system and the eluate cooling system are also described. Under the conditions studied, it was found that the carbon column at elevated temperature was stable and could be applicable to any compounds that are durable under these conditions. The peptide bonds at this high temperature and at this acidity were still stable enough for analysis, but the indole residues showed poor stability.

Amino Acid Sequence↗

PubMed1996

Histologic study of the small pulmonary arteries in 38 patients with pulmonary atresia and intact ventricular septum.

The structure of the small pulmonary arteries was studied during autopsies performed on 38 patients with pulmonary atresia with intact ventricular septum. The thicknesses of the media of these small pulmonary arteries measured using a quantitative morphometric method varied widely. However, there was a notable tendency toward thinning of the media, especially in neonates. In cases in which the patient had undergone prostaglandin E1 treatment, the media was thinner, which suggests that the longer the treatment, the thinner the media. Intimal lesions were observed in 18 of the 38 patients (47%), including 12 of the 22 neonates (55%). Intimal lesions were also found in the patients with thinner media. Based on these results, we propose that organized thrombus formation and intimal proliferation are more likely to develop in patients with reduced pulmonary blood flow, such as in those with pulmonary atresia and intact ventricular septum. In prostaglandin-treated patients, an imbalance between the markedly thinner median muscle and the relatively higher pulmonary blood flow and pressure may contribute to fibrous intimal proliferation. Small pulmonary arteries with a strikingly thinner media may be vulnerable to higher pressure, predisposing the patient to the development of intimal lesions.

Alprostadil↗

PubMed1995

[Correlation between pulmonary vascular changes and hemodynamic parameters during exercise before and after mitral valve surgery].

Sixteen cases with mitral valvular disease were studied with regard to the correlation between pathological changes in the pulmonary vasculature and pulmonary hemodynamics during exercise before and after surgery. In muscular pulmonary arteries obtained by open lung biopsy, medial wall thickness (MWT) was 13.8 +/- 3.2% and intimal thickness (IT) was 37.3 +/- 13.5%. MWT was correlated with IT (r = 0.60, p < 0.05). Wall thickness in pulmonary veins was 8.21 +/- 1.8%. Preoperative mean pulmonary arterial pressure (MPAP) during exercise was 45.9 +/- 9.4 mmHg, and decreased significantly to 38.1 +/- 11.3 mmHg postoperatively. However, in 4 patients, MPAP during exercise increased after surgery. Pulmonary vascular resistance (PVR) during exercise was unchanged before and after surgery (2.74 +/- 1.90 U.M2-->2.69 +/- 1.3 U.M2). MWT was significantly correlated with preoperative MPAP at rest only. In patients showing an increase of MPAP during exercise postoperatively, mean MWT was 16.2% and mean IT was 47.4%. In conclusion our data suggest that postoperative pulmonary hemodynamics does not improve in patients whose MWT exceeds 15% and IT exceeds 40% and that irreversibility may be due to pulmonary vascular lesions.

Adult↗