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Biomedical subjects

S Ota

Publications and source records attributed to S Ota.

At least 19 recordsLinked to original sources
PubMed1992

Studies on the function mechanism of a Formosan grey mullet protamine-mugiline beta M6: interaction of the M6 and M6 fragments with DNA.

The interaction of three peptide segments of one component of Formosan grey mullet protamine (mugiline beta M6), obtained by chemical and enzymatic cleavage, with DNA was studied by spectroscopic measurement, thermal denaturation and circular dichroism. The data obtained were then compared with those of whole M6 and other fish protamines such as salmine of salmon and clupeine of herring. M6-B-I, which lacks C-terminal 11 amino acids in M6, showed significantly different properties. It showed remarkably high DNA aggregating ability which was due to a conformational change of DNA from B to A form. The conformational change of DNA induced by the binding of M6-B-I was reproduced by the carboxypeptidase B digestion of DNA-M6 complex. From these results, the arginine-rich, C-terminal domain of the M6 molecule was estimated to be essential for natural DNA binding.

Amino Acid Sequence↗
PubMed1992

Primary structures of sardaines Z1 and Z2, protamines isolated from striped bonito (Sarda orientalis).

Striped bonito protamine, sardaine, was isolated from the sperm of striped bonito (Sarda orientalis) by extraction with sulfuric acid followed by ion-exchange chromatography. The preparation gave a single band upon polyacrylamide gel electrophoresis. Sardaine consists of 34 amino acid residues, and its sequence is: Pro-Arg-Arg-Arg-Arg-Arg-Ser(Ala)-Ser-Arg-Pro-Val-Arg-Arg-Arg-Arg-Arg-Tyr -Arg- Arg-Ser-Thr-Ala-Ala-Arg-Arg-Arg-Arg-Arg-Val-Val-Arg-Arg-Arg-Arg. At position 7, serine (sardaine Z1) is partially replaced by alanine (sardaine Z2). The ion spray mass spectrum shows that sardaines Z1 and Z2 have molecular masses of 4,612.49 and 4,596.09 Da, respectively. The sequence of sardaine Z1 is 100% identical with that of thynnine Z2 from tuna fish (both fish belong to Scombridae, Perciformes).

Amino Acid Sequence↗
PubMed1992

The effects of acid secretagogues on protective agents of gastric cells from adult rabbits in vitro.

Endogenous prostaglandin and mucus have been recognized as important protective factors in the gastric mucosa. However, the regulatory mechanisms of these agents have not been well studied. The aim of the present study was to investigate the effects of acid secretagogues on cyclic adenosine monophosphate (cAMP) formation, prostaglandin E2 (PGE2) production, and mucus secretion by isolated parietal cells and culture mucous cells from adult rabbits. Rabbit parietal cells were enriched by nonlinear Percoll gradients after the isolation of rabbit gastric mucosal cells with collagenase and ethylenediaminetetraacetic acid (EDTA). Rabbit gastric mucous cells were cultured in 10% fetal bovine serum added to Ham's F12 medium. As gastric acid secretagogues, histamine, carbachol, gastrin, and 2-chloroadenosine were tested. To evaluate the effects of the second messengers of cellular signal transduction on protective agents, A23187, which is a calcium ionophore, and cAMP were used. PGE2 and cAMP were measured by radioimmunoassay. The release of [3H]glucosamine from prelabeled cells was used as an indicator of mucus secretion. Histamine, carbachol, gastrin, and 2-chloroadenosine did not modulate PGE2 production by parietal cells. Exogenously administered cAMP did not affect PGE2 production by parietal cells, whereas it was significantly increased by A23187. 2-Chloroadenosine but not histamine or carbachol significantly increased cAMP formation by mucous cells. Histamine, carbachol, and gastrin did not have significant effects on PGE2 production by mucous cells. 2-Chloroadenosine, which increased cAMP, also did not modulate PGE2 production. A23187 but not cAMP increased PGE2 production by mucous cells. None of the acid secretagogues used in the present study modulated mucus secretion. A23187 but not cAMP significantly increased mucus secretion by cultured mucus cells.(ABSTRACT TRUNCATED AT 250 WORDS)

2-Chloroadenosine↗
PubMed1992

Cytologic assessment of peroperative pleural effusion and prognosis in lung cancer patients who underwent resection.

Twenty-five of 108 lung cancer patients who underwent resection had cytologically positive pleural effusions. The rate at which cancer cells were detected was not related to the amount of the effusion. Almost one third of patients with cancer cells in effusion were alive at the end of the third postoperative year, provided that the pleura itself was free of metastasis at the time of operation. Correlation of the cytologically positive rate of pleural effusion (Y) with the degree of pleural metastasis (X1), the degree of pleural involvement (X2), or the degree of nodal involvement (X3) was analyzed using the Hayashi's quantification method type I. The multiple correlation coefficient was 0.843. Partial correlation coefficients of X1, X2, and X3 were 0.733, 0.446, and 0.653, respectively. Pleural metastasis had the strongest effect on the cytologically positive rate of pleural effusion.

Adult↗
PubMed1992

An improved method of bronchial stump closure for prevention of bronchopleural fistula in pulmonary resection.

We performed 880 pulmonary resections from January 1982 to June 1988 using Sweet's procedure for closure of the bronchial stump, in which 39 patients (4.4%) developed bronchial fistulas. Bronchoscopic studies showed that bronchopleural fistulas were located mainly at the corner of the stump. This indicates that the corner is the point with the highest tension when Sweet's procedure is employed. In some cases, stumps were injured by suture materials, resulting in bronchopleural fistulas. Since July 1988, bronchial stumps have been closed by using two pairs of teflon pledgets with additional interrupted sutures. From July 1988 to April 1990, 288 patients were treated by this new method, and only one of them developed bronchopleural fistula. This new method prevents injury of the stump by suture material and reduces the tension at the bronchial stump for a long time. Thus, pulmonary resections can be safely employed even after anti-cancer chemotherapy and/or radiation therapy.

Bronchi↗
PubMed1992

[Evaluation of renal function and prediction of renal functional recovery in children with unilateral hydronephrosis using renal pelvic urine].

In 29 children with unilateral hydronephrosis who underwent surgery at the age from 2 months to 15 years (27 patients with ureteropelvic junction stenosis and 2 with obstructive megaureter), beta 2-microglobulin (beta 2-MG), alpha 1-microglobulin (alpha 1-MG), N-acetyl-beta-D-glucosaminidase (NAG) and albumin were determined in renal pelvic urine from the hydronephrotic kidney to evaluate renal dysfunction accompanying urinary tract obstruction. Moreover, it was also examined whether it is possible to predict functional recovery of the hydronephrotic kidney on the basis of relation between these indices and pre- and postoperative changes in renal dimercaptosuccinic acid (DMSA) uptake rate. The values of beta 2-MG, alpha 1-MG, NAG and albumin in urine from the renal pelvis were high in 48%, 50%, 75% and 83% of the patients, respectively. Among the patients of one year and up, those with low preoperative DMSA uptake rate tended to have high values of beta 2-MG, alpha 1-MG and NAG. On the contrary, albumin level was high in 78% of patients who had good preoperative DMSA uptake rate. With respect to the relation between pre- and postoperative changes in DMSA uptake rate and each index, beta 2-MG and alpha 1-MG were high in 73% and 62% of patients who exhibited a marked increase in postoperative DMSA uptake rate. In patients without a remarkable change in DMSA uptake rate before and after surgery, on the other hand, the values of these were high only in 25% and 36%.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylglucosaminidase↗
PubMed1992

[Effect of unilateral hydronephrosis upon contralateral renal growth].

UNLABELLED: To evaluate the effect of hydronephrosis on the growth of contralateral normal kidney, following experiment was designed and performed. EXPERIMENT: Three to four weeks old S-D rats weighing 80-90 g were used. The kidney development of these rats is considered to be roughly equivalent to that of a one year old child. Those rats were divided into three groups: (1) left nephrectomy (group N), (2) left ureteral ligation (group H), and (3) sham operation (group S). Bromodeoxy uridine (BrdU) was administered intraperitoneally on the 1st, 3rd, 5th, 7th and 14th days after operations. One hour after injection of BrdU, right kidneys were removed and wet weight and labelling index (LI) of BrdU were calculated. Compensatory renal growth of right kidneys was observed in both group H and group N on and after 1st or 3rd day. In group N, the growth was accompanied by cellular proliferation, while in group H, hypertrophy was the major finding for up to 5th day. From 7th day on, when significant disorders became histologically evident in the left hydronephrotic kidneys, cell proliferation was also observed in the group H. The above results indicate that compensatory renal growth occurred in the contralateral normal kidney after unilateral ureteral ligation. Although proliferation of right renal tubular cells were recognized when significant tubular and interstitial damage of the left hydronephrotic kidneys were observed, hypertrophy was a major finding in an early stage. We suggest that these results were attributed to (1) reduction of nephron triggered to proliferate tubular cells and (2) the existence of hydronephrotic kidney inhibited tubular cell proliferation.

Animals↗
PubMed1992

[Molecular biological study on multifocal infection of HPV in uterine cervix, vagina and vulva].

Vaginal and vulvar scrapes from 30 patients which have HPV types 16 or 18 positive cervical neoplasia (13 of mild dysplasia, 5 of moderate dysplasia, 4 of severe dysplasia, 3 of carcinoma in situ, and 5 of invasive carcinoma) were examined by the polymerase chain reaction (PCR), to detect amplified E7 gene of HPV types 16 and 18 DNA sequences. In 24 vaginal and 15 vulvar scrapes, the same type of HPV as in cervical scrapes was detected. The frequencies of HPV DNA in vaginal and vulvar scrapes for histological diagnosis of cervical neoplasia were 84.6% (11/13) and 53.8% (7/13) in mild dysplasias, both were 100% (5/5) in moderate dysplasias, 75% (3/4) and 25% (1/4) in severe dysplasias, 66.7% (2/3) and 33.3% (1/3) in CISs, and 60% (3/5) and 20% (1/5) in invasive carcinomas, respectively. The results of vulvar scrapes showed that the frequency of HPV DNA in mild and moderate dysplasias was significantly higher than that in severe dysplasias, CISs and invasive carcinomas (p < 0.05). We suggest that, in addition to the investigation for the natural history of HPV infection, cell dynamics, local immunological status and any other factors in the HPV-infected lesion must be investigated to clarify the carcinogenesis of HPV in the uterine cervix. Furthermore, HPVs detected in the vagina and vulva were thought to have disappeared without reaching an integrated form during the follow-up of cervical neoplasia with HPV infection over a long period.

DNA, Viral↗
PubMed1992

[Acid base balance in the digestive system].

The mechanisms of acid base balance in digestive organs, including stomach, intestine as well as liver, have been described in the present paper. The stomach secrets large amount of acid as well as sodium bicarbonate, so that hydrogen ion would be lost in the severe vomiting state such as pyloric stenosis, resulting in metabolic alkalosis and hypokalemia. In the diarrheal condition, sodium bicarbonate would be lost in large amount, causing metabolic acidosis and hypokalemia. Hepatic failure induces the respiratory alkalosis of which mechanisms have not been clarified yet. In any case, urgent correction of acid base imbalnce would be crucial. It is, however, obscure to date how the systemic acid base imbalnce affects the function of the digestive system. This issue would be promising field in the investigation of digestive diseases.

Acid-Base Imbalance↗
PubMed1992

Results of surgical treatment for roentgenographically occult bronchogenic squamous cell carcinoma.

Ninety-four patients with roentgenographically occult bronchogenic squamous cell carcinoma had surgical resection. Fifty-three reported having no symptoms. In 83 carcinoma was detected by cytologic examination of the sputum during lung cancer screening. The carcinomas were located in segmental bronchi (34 cases), subsegmental bronchi (19 cases), divisional bronchi (17 cases), and subsubsegmental or more peripheral bronchi (15 cases). The number of cases classified by TNM staging were 16 Tis N0 M0, 72 T1 N0 M0, 4 T1 N1 M0, and 2 T2 N1 M0. Extrabronchial invasion of the resected carcinoma was observed in 17 lesions (16 cases). Five of six patients with lymph node metastasis in the resected specimens had carcinoma with extrabronchial invasion. Multiple primary lung cancers were observed in nine patients at the time of operation and in seven subsequently. Four of seven patients with subsequent primary lung cancer had surgical resection, and no recurrence was observed after the second operation. There were two deaths from lung cancer: One was caused by subsequent primary lung cancer and the other by mediastinal lymph node metastasis. In the 75 patients with intrabronchial cancer invasion and without lymph node metastasis who had complete resection, there was no local recurrence or metastasis of cancer. The 5-year survivals were 80.4% (death from all causes) and 93.5% (death from lung cancer). Although subsequent primary lung cancer is troublesome, operation is a reliable treatment for occult bronchogenic squamous cell carcinoma.

Bronchoscopy↗
PubMed1992

[Re-evaluation with abridged life tables of the prognosis of lung cancer patients who underwent surgical therapy].

Some lung cancer patients after surgical treatment die as a result of pneumonia or cardiac failure without recurrence of lung cancer months or years after surgery because many such patients are aged or have decreased lung function. Surgical treatment may be partly to blame for these deaths. In this article, to evaluate the contribution of surgical treatment to deaths resulting from other disease, we calculate predicted survival rates using abridged life tables and compute relative survival rates. From 1952 to 1985, a total of 1289 lung cancer patients underwent surgical resection of lung cancer in our department. We calculated some kind of survival rates according to age, stage, and operative procedure. Each case was classified according to age (5-year periods), year of operation (5-year periods), and sex. The 5-year survival rate indicated by the abridged life tables in each class was regarded as the 5-year predicted survival rate of the case. The mean of 5-year predicted survival rates of all cases in a group was regarded as being the 5-year predicted survival rate of the group. The ratio (actual survival rate of the group/predicted survival rate of the group) was also calculated. The ratio of the patients who had stage O, I, or II diseases tended to decrease according to age. This fact supposed that the number of deaths resulting from other diseases with no recurrence of lung cancer in which surgical treatment contributed to death increased in the elderly. In the other hand, this tendency did not exist in the patients who had stage IIIA diseases.

Adolescent↗
PubMed1992

[Hyperkalemia in a cyclosporine A-treated allogeneic bone marrow transplant recipient].

A 9-year-old boy was admitted with the diagnosis of myelodysplastic syndrome (FAB RAEB in T). The patient was treated with busulfan and cyclophosphamide and transplanted with bone marrow cells from an HLA identical sister. Cyclosporin A (CyA) and short term methotrexate (MTX) was given for prophylaxis against graft versus host disease (GvHD). The serum potassium value was observed to increase to 6.3 mEq/l during the period of CyA therapy. The serum potassium value returned to 4 mEq/l when CyA treatment was decreased to a serum concentration of less than 50 ng/ml (FPIA). On day 90 post transplantation the patient was diagnosed as relapsed. The patient was preconditioned with cyclophosphamide and total body irradiation and a second bone marrow transplantation was performed using cells from the same donor. He was treated again with CyA and short term MTX for the prevention of GvHD. Once again the patient became hyperkalemic with 6.8 mEq/l. The serum creatinine level was 0.9 mg/dl, the GFR was 52.1 ml/min, FEK was 7.1%. Pseudohypoaldosteronism or hyporeninemic hypoaldosteronism was suspected. To investigate this possibility a renin/aldosterone stimulation test was performed. We speculate that an idiosyncratic response to CyA resulted in pseudohypoaldosteronism and produced a defect in potassium secretion.

Bone Marrow Transplantation↗
PubMed1992

[Experience of Nd-YAG laser treatment in roentogenographically occult bronchogenic squamous cell carcinoma].

Out of 201 patients with roentogenographically occult bronchogenic squamous cell carcinoma, 165 lesions underwent surgical operations, while 41 lesions underwent non-invasive therapy. The 5-year survival rate including all causes of death, was significantly higher in the surgical operation group than that in the non-invasive therapy group (83% vs 43%). Among 14 cases who received Nd-YAG laser treatment, one case died but 4 cases are alive bearing cancer. Since time span of follow-up period is short, it is hard to say that the prognosis of the Nd-YAG laser therapy in fair. Nd-YAG laser treatments were effective for cancers which did not invade beyond bronchial cartilage. From the bronchoscopic examinations and studies with resected lungs, we suggest that Nd-YAG laser treatments may be effective when cancer is extended within 10 mm wide and has only a slight findings in bronchoscopy.

Aged↗
PubMed1991

Protective effect of tauroursodeoxycholate against chenodeoxycholate-induced damage to cultured rabbit gastric cells.

Ursodeoxycholate (UDC) and tauroursodeoxycholate (TUDC) have been reported to be protective against liver injury induced by other bile salts. UDC also has been shown to be effective against refluxed bile-induced gastritis after gastric surgery. However the mechanism of the therapeutic effect of UDC on gastric mucosa has not been known. In the present study, cytoprotective actions of UDC and TUDC against chenodeoxycholate (CDC)-induced gastric injury were investigated using rabbit gastric cell cultures without systemic factors. Rabbit gastric mucosal cells were cultured after the isolation of rabbit gastric cells with collagenase and ethylenediaminetetraacetic acid. Cytotoxicity was quantified by measuring 51Cr release from prelabeled cells and MTT assay. Prostaglandin (PG) E2 was assayed by radioimmunoassay. Concentrations of CDC greater than 0.5 mM or UDC greater than 5 mM caused cellular damage and increased 51Cr release in a dose-dependent and time-dependent fashion, while TUDC up to 10 mM did not. TUDC, but not UDC, showed a significant decrease of CDC (1.5 mM)-induced 51Cr release dose dependently. The protective effect of TUDC against CDC-induced damage was confirmed by MTT assay. On phase-contrast microscopy, disruption of monolayers induced by CDC (1.5 mM) was clearly protected by TUDC (10 mM). Free radical scavengers (500 units/ml of superoxide dismutase, 300 units/ml of catalase, and 100 mM of dimethyl sulfoxide) or a calcium blocker (10(-7)-10(-5) M verapamil) did not show significant protection against CDC-induced damage. Deprivation of Ca2+ in the media did not affect CDC-induced damage. Thus free radicals or Ca2+ might not be involved in the cell toxicity of CDC.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Characterization of a newly established cell line (JR-St) derived from human gastric signet ring cell cancer, producing tumor markers.

Despite the importance of in vitro study of gastric cancer, there are very few established cell lines derived from human gastric carcinoma. We have recently established a new cell line derived from human gastric cancer which has the ability to produce tumor markers. This cell line has been designated JR-St. This cell line was derived from the cerebrospinal fluid of a 37-yr-old female patient who had metastatic brain tumor of signet ring cell gastric adenocarcinoma. This cell line has been maintained for more than 24 months through 80 passages with stable growth. PAS staining showed intracellular mucin granules. Transmission and scanning electron microscopy revealed cells with numerous microvilli and fine projections as well as intracellular granules, indicating mucin. This cell line had the ability to produce high concentrations of tumor markers such as carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9. Thus Thus this cell line should provide a very useful tool for the investigation of gastric cancer such as analysis of tumor markers as well as effects of anti-cancer drugs or growth factors.

Adenocarcinoma, Mucinous↗
PubMed1991

A case of malignant lymphoma in the liver treated by percutaneous ethanol injection therapy under peritoneoscopic observation.

A 41-year-old woman with non-Hodgkin's lymphoma in the liver was treated with percutaneous ethanol injection therapy. Ethanol injection was performed twice under ultrasonographic guidance for a lesion inside the liver and once under peritoneoscopic observation for lesions on the surface of the liver. CT performed after treatment showed that sizes of the lesions decreased and that the lesions were not enhanced by contrast medium, indicating lack of blood supply and necrosis of the lesion. Ultrasonography performed after treatment did not show any lesions in the liver. There was no sign of recurrence or metastasis.

Adult↗
PubMed1991

Endothelin-1 secretion from cultured rabbit gastric epithelial cells.

It has been shown that endothelin-1 (ET-1) is synthesized in various extraendothelial tissues. Although ET-1 has been reported to have potent ulcerogenic action in the stomach, the synthesis and physiological roles of ET-1 in the gastric mucosa are poorly understood. The aim of the present study was to investigate whether or not cultured gastric epithelial cells secrete ET-1 and possess autocrine functions. Gastric epithelial cells from rabbits were cultured in medium supplemented with 10% FBS after isolation. ET-1 was extracted by C18 columns from serum-free culture media and measured by radioimmunoassay (RIA). Effects of ET-1 on the intracellular concentration of calcium of the cultured cells were examined with Indo-1. Prostaglandin E2 (PGE2) was measured by RIA. Primary cultures of gastric epithelial cells were mainly composed of mucous cells. ET-1 was detected in the culture medium by RIA, and 70 pg/10(6) cells/24 h of ET-1 was secreted by cultured cells. Tumor growth factor-beta (4 ng/ml) and thrombin (8 U/ml) significantly increased ET-1 secretion. Exogenously administered ET-1 up to 10(-6) M neither modulated the intracellular calcium concentration nor affected PGE2 release by these cells. These results suggest that gastric mucous cells in culture secrete ET-1. Further studies are needed to explore the possible involvement of such paracrine function in the reported ulcerogenic action of ET-1.

Animals↗