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Biomedical subjects

H Sasamoto

Publications and source records attributed to H Sasamoto.

At least 19 recordsLinked to original sources

Immunocytochemical localization of salivary peptide P-C in human submandibular gland.

Human saliva contains a proline-rich polypeptide, salivary peptide P-C, which potentiates insulin release and reduces glucagon release from perfused rat pancreas to decrease blood glucose level. To elucidate the process of secretion into humoral fluid of this peptide morphologically, we investigated ultrastructural localization of P-C in human submandibular gland by immunogold technique with anti-peptide P-C whose specificity to P-C was confirmed by immunoblotting. The labeling with gold particles which represents the distribution of P-C-like-immunoreactivity (P-C-LI) was detected in the secretory granules and rough endoplasmic reticula of the acinar serous cells and in few mucosa cells. P-C-LI was also observed in the lumen of striated duct but not intracellularly in the ductal cells themselves, indicating that P-C is not probably reabsorbed there. These results suggest that salivary peptide P-C is present in acinar serous cells, is secreted into the oral cavity, and may be reabsorbed through the digestive tract to modulate the blood glucose level after feeding.

Aged

Extracellular production of mouse interferon beta by the Bacillus subtilis alpha-amylase secretion vectors: antiviral activity and deduced NH2-terminal amino acid sequences of the secreted proteins.

Using two Bacillus subtilis alpha-amylase secretion vectors, mouse interferon-beta (IFN-beta) cDNA was expressed. Ten kinds of mature and hybrid forms of biologically active mouse IFN-beta proteins were synthesized in B. subtilis and were secreted into the culture medium. Similar amounts of proteins, which were determined by immunoblot analysis, were secreted from the B. subtilis transformants, while the antiviral activity in the medium was markedly different in each one of them. The highest antiviral activity was observed in a hybrid protein, in which eleven amino acids consisting of the prosequence of alpha-amylase (eight amino acids) and three amino acids encoding in the HindIII linker DNA were assumed to be extended in front of the Leu residue at position 6 of the mature form of mouse IFN-beta. Its activity was higher than that of the mature form of the mouse IFN-beta secreted from a B. subtilis transformant. These results indicate that the amino acid sequence around the NH2-terminal region of the mouse IFN-beta is closely related to the antiviral activity, but the NH2-terminal amino acid is not. The hybrid proteins of mouse IFN-beta show no interferon activity against a human cell line, HEL.

Amino Acid Sequence

Signal peptide of Bacillus subtilis alpha-amylase.

Mature alpha-amylase of Bacillus subtilis is known to be formed from its precursor by the removal of the NH2-terminal 41 amino acid sequence (41 amino acid leader sequence). DNA fragments coding for short sequences consisting of 28 (Pro as the COOH terminus) 29 (Ala), 31 (Ala), and 33 (Ala) amino acids from the translation initiator, Met, in the leader sequence were prepared and fused in frame to the DNA encoding the mature alpha-amylase. The secretion activity of the 33 amino acid sequence was nearly twice as high as that of the parental 41 amino acid sequence, whereas the activity of the 31 amino acid sequence was 75% of that of the parent. In contrast, almost no secretion activity was observed with the 28 and 29 amino acid sequences. The signal peptide cleavage site of the precursor expressed from the plasmid encoding the 33 amino acid sequence was located between Ala and Leu at positions 33 and 34 and that from the 31 amino acid sequence between Thr and Ala at positions 33 and 34. The NH2-terminal amino acid from the latter corresponded to the 3rd amino acid of the mature enzyme. These results indicated that the functional signal peptide of the B. subtilis beta-amylase consists of the first 33 amino acids from the initiator, Met.

Amino Acid Sequence

[Efficacy of etoposide in bone metastasis of breast cancer].

We have used ADM, MMC, CDDP and other drugs for a case of bone metastasis of breast cancer, but the bone destruction was advanced and she could not walk. We have also used etoposide, a new chemotherapeutic drug, for the same case. Two months later bone sclerosis was seen by X-ray film and pain disappeared. Bone sclerosis then advanced after 6 months, she has begun to stand, and after 8 months she has been able to walk with a cane. There was no severe side effect. Etoposide was very effective for bone metastasis of the breast cancer.

Bone Neoplasms

Active forms of chymotrypsin C isolated from autolyzed porcine pancreas glands.

Four active forms of chymotrypsin C (C1, C2A, C2B, and C3) were isolated from the autolyzed porcine pancreas glands. Their molecular weights were estimated by SDS-polyacrylamide gel electrophoresis to be 29 100 for C1, 26 300 for C2A and C3, and 25 500 for C2B. The kinetic analyses of esterase activity of the enzymes toward Ac-LLeu-OEt and Ac-LPhe-OEt showed that chymotrypsin C1 hydrolyzed the two substrates more efficiently than did chymotrypsin C3. Chymotrypsin C1 consisted of chain A (H-Cys-...-Asn-OH, Mr 886) and chain BC (H-Val-...-Lys-OH, Mr 28 200). Chymotrypsin C3 consisted of the two components of C3L and C3S that could be dissociated in the presence of 2.3% SDS. C3L consisted of the chain A and the chain C (H-Ser-...-Lys-OH, Mr 13 600). C3S was the chain B (H-Val-...-Lys-OH, Mr 11 800). These kinetic and chemical analyses show that chymotrypsins C1 and C3 correspond to chymotrypsin A delta and A alpha, respectively.

Amino Acids

[Floating knee fracture (ipsilateral fracture of the femur and tibia)--treatment by closed Ender nailing].

Fourteen cases of ipsilateral fractures of the femur and tibia (floating knee fracture) were reviewed and patients were graded according to the type of fracture and the method of treatment. Using the criteria for assessment described by Karlström and Olerud, patients were graded as excellent, good, fair and poor. Excellent results were achieved in five patients, good in three and fair in six. When the fracture extended into the knee, it caused knee problem in three out of five. In ten cases the femoral shaft fractures were nailed and in five both bones were nailed. Nailing of both femur and tibia gave good or excellent result in all five cases. As the comminution is often severe in the cases of floating knee fracture, intramedullary nailing by Küntscher may be difficult. We have introduced a closed Ender nailing for femoral and tibial shaft fractures and we have found that this method is also useful for the floating knee fracture. It is advantageous for this type of fracture, because it is technically simple, it has wide indications and it results in rapid bone union without knee disturbance.

Adolescent

Evaluation of pericardial effusion with computed tomography.

Evaluation of pericardial effusion was attempted with computed tomography in 11 patients. The volume and distribution of pericardial fluid were assessed with satisfactory resolution and the nature of the fluid was estimated by the difference in x-ray transparency (CT numbers). The volume of pericardial fluid calculated by tomographic methods ranged from 25 ml. to 585 ml. and agreed well with the surgically drained fluid volume. The CT numbers of the pericardial effusion due to renal or heart failure, acute viral pericarditis, hypothyroidism, and hemopericardium were +12 to +13, +20, +28 to +30, and +26 to +40, respectively. Therefore the volume and gross nature of the pericardial fluid could be estimated noninvasively with computed tomography.

Acute Disease

Evaluation of cardiac diseases with computed tomography.

Fifty-six consecutive patients with various cardiac diseases were studied with a third-generation whole body computed tomographic system. Enhancement was performed by intravenous injection of angiographic contrast medium. Identification of the great vessels, atria and ventricles, and evaluation of abnormalities in these structures were possible by cardiac computed tomography. For example, enlarged left ventricle in the left ventricular volume load, enlarged right ventricle in the right ventricular volume load or hypertrophied interventricular septum in idiopathic hypertrophic subaortic stenosis were revealed with a satisfactory resolution. Pericardial effusion and intracardiac thrombi were most precisely assessed by computed cardiac tomography.

Adult

Holter system electrocardiographic studies on 617 cases.

Holter system electrocardiograms were recorded for 617 patients who were treated at the Department of Cardiology, Tokai University Hospital. In cases of arrhythmia, ventricular premature contraction (VPC) was the most predominant, in 291 cases (69%) out of 423 with arrhythmia, followed by 59 (14%) with supraventricular premature contraction (SVPC), 23 (5.4%) with paroxysmal atrial tachycardia, 17 (4%) with second degree A-V block and 10 (2.3%) with transient atrial fibrillation (AF). In addition, nine (2.1%) cases of ventricular tachycardia (VT), one (0.2%) of transient ventricular fibrillation (VF) and one (0.2%) of third degree A-V block were found in particularly severe arrhythmia cases. Six out of nine cases of VT were cases of acute myocardial infarction (AMI) and all died suddenly while in the hospital or after discharge. Mild or moderate changes in ST-T were often observed even in normal subjects. Of the 617 cases, only 18 (2.9%) showed a significant elevation or depression of ST. Among these, three definitely had variant angina pectoris (Prinzmetal type). The above results indicate Holter EKGs are very useful for the diagnosis of arrhythmia and can also be used as a means of evaluating the prognosis in some cases, but there still are some problems in connection with its use for the diagnosis of ischemic heart disease except for the diagnosis of variant angina pectoris.

Adolescent

Chest roentgenograms in primary pulmonary hypertension.

The characteristics of 59 chest roentgenograms of patients with primary pulmonary hypertension were investigated and compared with roentgenograms of 100 healthy control subjects. The relationship with pulmonary hemodynamics was also examined. In primary pulmonary hypertension, there was remarkable protrusion of the main pulmonary artery; the DPA (T/2) and the PL/T index (see text) had high values. These indices depend mainly on pulmonary hypertension, but are partially determined physically by the size of the individual heart. The width of the descending branch of the right pulmonary artery (dPA) was about double the control value (P less than 0.001). The cardiothoracic ratio was significantly increased in primary pulmonary hypertension and there was a positive correlation between the ratio and the mean right atrial pressure (r = 0.37, P less than 0.01). However, there was no correlation with pulmonary arterial pressure or other pulmonary hemodynamic parameters. These results indicate that the increase in the cardiothoracic ratio in primary pulmonary hypertension is caused mainly by right heart failure.

Adolescent

Arrhythmias in primary pulmonary hypertension.

Through the examination of 171 electrocardiograms (ECG) of 101 patients with primary pulmonary hypertension (PPH), the following conclusions were obtained. Arrhythmias were found in 27 (26.7%) of the 101 patients. Among the surviving cases, arrhythmias were found in 8 (17.8%) out of 45 patients, but among the decreased cases, the figure was higher, 19 (33.9%) out of 56. There were instances of more than one kind of arrhythmias in the same patient and a total of 34 types of arrhythmias were noted. The main types of arrhythmias were sinus tachycardia (13 cases), sinus bradycardia (6 cases), and first degree A-V block (5 cases), which accounted for 70% of the total. Sinus tachycardia was observed in only 2 of the survivors but in 11 of the decreased cases, which showed a significant difference (p less than 0.05). First A-V block were all induced by digitalis. Wenckebach type of second degree A-V block was noted in only 1 case and it was also induced by digitalis. Since severe attacks of ventricular arrhythmias were very rare in these cases with PPH, it is difficult to consider the Adams-Stokes syndrome as the cause of syncopal attacks or sudden death. However, it is necessary to further investigate nodal functions by means of continuous ECG monitoring, the overdrive suppression test and His bundle ECGs.

Adolescent

A case of persistent atrial standstill.

A case of persistent atrial standstill is described. The criteria for diagnosing atrial standstill are separated into two categories: the lack of electrical atrial activity and the lack of mechanical atrial activity. Echocardiography of the anterior mitral leaflet is to be used as one of the noninvasive methods for the diagnosis of the lack of mechanical atrial activity.

Adolescent