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Biomedical subjects

T Okada

Publications and source records attributed to T Okada.

1,398 records · Page 78Linked to original sources
PubMedDate not supplied

Different expression of esterase variants in rat hepatic and hepatoma-derived cell lines detected by electrophoresis.

Esterases in nine rat hepatic and hepatoma-derived cell lines and normal rat liver homogenate were detected by polyacrylamide gel electrophoresis coupled with active staining with alpha-naphthyl acetate or butyrate as a substrate. The esterase band patterns of the non-cancerous and oncogene-transformed cell lines were alike, but different from those of hepatoma cell lines and normal rat liver homogenate. The former groups of cells might have completely lost the characteristics of rat liver parenchymal cells, or else they might have their origin at cells other than liver parenchyma. The esterase patterns of the hepatoma cell lines (e.g., McA-RH7777) and the normal rat liver highly resembled with each other, exemplifying the slight biochemical deviation of cancer from normal cells. However, two-dimensional electrophoretogram for the McA-RH7777 cell line showed a prominent esterase spot (pI 6.0-M(r) 110 kDa) that was lacking in the normal liver. This result indicates that there is invariably some change in esterase expression between the cancer cells and the normal liver cells.

Animals↗
PubMedDate not supplied

Chemopreventive effects of ferulic acid on oral and rice germ on large bowel carcinogenesis.

Effects of ferulic acid (FA) known as a major constituent of rice bran or germ on 4-nitroquinoline-1-oxide (4NQO)-induced oral carcinogenesis were examined in 4 groups of male rats. The incidences of tongue carcinomas and preneoplastic lesions (severe dysplasia) in rats of the group given FA in the diet at a dose of 500 ppm after exposure to 4NQO for 5 weeks in drinking water at a dose of 20 ppm, was significantly lower on termination of the experiment (32 weeks) in the group with the carcinogen alone (P < 0.005 and P < 0.001 respectively). The results suggest chemopreventive activity for this phenolic compound on oral cancer. Modifying effects of rice germ on azoxymethane (AOM)-induced formation of aberrant crypt foci (ACF) were also examined, in 8 groups of male F344 rats. Numbers of ACF/colon, ACF/cm2 and aberrant crypts/colon in the group treated with AOM (15 mg/kg s.c. once a week for 3 weeks) and gamma-amino butylic acid (GABA)-enriched defatted rice germ (2.5% in diet) or the group with AOM and rice germ (2.5% in diet) were smaller than those of the group with AOM alone (P < 0.005). Exposure to defatted rice germ or rice germ during the initiation phase or the post-initiation phase also decreased incidences of AOM-induced large bowel neoplasms (P < 0.05). These results suggest chemopreventive potential for rice germ on colonic neoplasia.

4-Nitroquinoline-1-oxide↗
PubMedDate not supplied

Irrigation of liver abscess: proposal of a novel method and possible indications.

We present here two suggestive cases in considering the advantages and disadvantages of irrigation of pyogenic liver abscess: one patient developed an intrahepatic hematoma as an unusual sequela, while the other was successfully treated by abscess irrigation, overcoming failure of percutaneous catheter drainage and the patient's seriously ill condition. Based on these cases, we propose a novel method of liver abscess irrigation via percutaneous drainage tubes with the following three characteristics: 1) use of a drip infusion apparatus for irrigant instillation and drainage in order to avoid elevation of pressure in the abscess, a source of potential life-threatening sequelae, 2) addition of contrast medium to irrigant, and 3) employment of computed tomography in dynamic equilibrium of irrigant in order to evaluate the efficacy of current irrigation. Of interest was the parenchymal enhancement around the irrigated liver abscess revealed by computed tomography with this method, which suggested that dissemination of abscess contents may be inevitable with irrigation. Although the indications for liver abscess irrigation must be considered carefully given the critical sequelae potentially associated with it, the method we present can be used as a second-line trial exclusively for liver abscesses refractory to first-line treatment with percutaneous catheter drainage or needle aspiration, since it can be used not only as a therapeutic procedure with mechanical washing or dilution of abscess contents but also as a diagnostic aid enabling more effective subsequent treatment by defining the areas in which drainage and irrigation is not effective.

Aged↗
PubMedDate not supplied

Experimental studies of a hybrid artificial esophagus combined with autologous mucosal cells.

Preliminary results, obtained using an artificial esophagus combined with autologous mucosal cells in dogs, are reported. The authors' prosthesis is a silicone tube coated with freeze dried collagen sponge. Cells infiltrate this collagen layer and synthesize new tissue, which will become the neoesophagus. The silicone tube imparts rigidity to the prosthesis and prevents infection, leakage, and dislocation of the prosthesis at the anastomotic site. After formation of the epithelized neoesophageal lumen, the silicone tube drops into the stomach as the result of peristalsis in response to food. Eventually, no artificial prosthesis remains in place, and the defect is replaced by ingrowing tissue. This process was shortened by mucosal cell seeding. Before replacement, the authors harvested oral mucosal (OM) cells, cultured them for 10 days, and seeded them in the collagen layer of the prosthesis just after anastomosis. The neo-esophageal lumen was formed 1 week after the operation without any local complications, infection, leakage, or stenosis, and 2 weeks later the firm, epithelized neoesophagus was completed. OM cell seeding accelerated not only epithelization, but also regeneration of mesenchymal tissue. Parallel with this, transmission electron microscopy showed that most of the cells in the neoesophagus exhibited large nuclei and prominent rough endoplasmic reticulum, indicative of active collagen production.

Animals↗
PubMedDate not supplied

Surgical experience with traumatic rupture of the thoracic aorta.

Nine cases of traumatic thoracic aortic rupture (TAR), operated on at St. Marianna University Hospital between July 1980 and December 1988, were reviewed in order to evaluate the role of contrast-enhanced CT in the early diagnosis of TAR. The absence of mediastinal hematoma on CT eliminated the need for aortography in 30 (38.5%) of the 78 patients suspected of having TAR on the basis of chest roentgenograms. The presence of mediastinal hematoma necessitated aortography in 48 patients. However, operative treatment was carried out without aortography in 3 patients who had specific signs of rupture on CT. CT proved to be a reliable indicator for the selection of the patients who need aortography. As a rule, emergency operations were performed in these patients. Simple aortic crossclamping was employed in 4 patients, and heparinless left heart bypass with the BioPump was performed for spinal cord protection in 2 recent patients without complication of embolization. Use of the BioPump as an adjunct in the repair of TAR appears to be promising.

Accidental Falls↗
PubMedDate not supplied

Clinical usefulness of cellulose acetate electrophoresis as a screening of proteinuria in childhood.

Urine samples from 110 patients with different proteinuric diseases in childhood were analysed by Cellulose Acetate Electrophoresis (CAE) and several samples were also analysed by Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE). CAE allowed the classification of proteinurias into 4 patterns; Tubular, Glomerular I, Glomerular II and Glomerular III, by albumin/globulin ratio, value of % gamma globulin fraction (% gamma) and alpha 1/alpha 2 globulin ratio. Proteinurias of the Tubular pattern included various diseases with tubular proteinuria, while proteinurias of the Glomerular I, II and III patterns included mainly postural proteinuria, proteinuria of nephrotic syndrome and proteinuria of various nephropathies, respectively. SDS-PAGE confirmed the tubular and the glomerular origins of the proteins. In the present study we described the clinical usefulness of CAE in the screening of proteinuric children for the following reasons. This method could be performed easily and immediately. This is one of the necessities for mass screening of proteinuric children. CAE can be helpful as one of indications of renal biopsy, since patients with the Glomerular III pattern often showed glomerular alterations and should be diagnosed histologically. Good correlation between % gamma and clinical data was found in follow-up study, so CAE is also helpful in understanding the disease course. Thus. CAE is recommended as a routine screening method of proteinuria as well as SDS-PAGE.

Child↗
PubMedDate not supplied

Excretion of urinary amino acids in children with postural proteinuria.

The urinary excretion of free amino acids was studied in urine specimens from 12 subjects with postural proteinuria in recumbent posture and after a period of upright lordotic posture. The lordotic posture produced an increased urinary excretion of total amino acid and 12 amino acids, particularly of taurine, glutamic acid, a-amino adipic acid, valine, leucine, ethanolamine and arginine. However, 90 min after the lordotic posture, all amino acids returned to the initial values. Although, many factors must be considered in the evaluation of the urinary excretion of amino acids, an increased urinary excretion of amino acids occurring after the lordotic posture may be the result of reabsorption disturbance of the renal tubules.

Adolescent↗
PubMedDate not supplied

A case of invasive primary mediastinal seminoma treated radically with replacement of the superior vena cava.

A primary mediastinal seminoma in a 30-year-old man, invading intraluminally into the superior vena cava, was radically treated with reconstruction of the superior vena cava using Gore-Tex grafts. The patient has been doing well without any evidence of tumor recurrence for two years after the surgery, with the grafts being nicely patent. Even when a primary mediastinal seminoma is growing locally into the major veins, the tumor could and should be treated radically, with performing reconstruction of the removed venous system. Gore-Tex graft seems to be acceptable as a venous substitute for major vein replacement.

Adult↗
PubMedDate not supplied

Angiographic retrieval of foreign bodies in pulmonary artery: a report of three cases.

Three cases of percutaneous retrieval of foreign bodies that migrated into the pulmonary artery are described in this paper. All of the intravascular foreign bodies were attributed to SVC catheters for intravenous hyperalimentation (IVH) therapy, an accidentally cut strip of indwelling SVC catheter in two patients and a fragment of guide wire used for the insertion of the SVC catheter in one patient. They were all successfully removed by fluoroscopic angiographic procedures using a snare loop retriever and grasping forceps. The technical aspects of the procedures are discussed here.

Adolescent↗
PubMedDate not supplied

Systemic arterial supply to normal basilar segments of the left lower lobe: role of continuous thin sliced CT.

A rare congenital anomaly of the left lower pulmonary artery is presented. A 39-year-old woman was admitted to our hospital for evaluation of a splenic mass. Abdominal CT disclosed abnormal vessels in the left lower lobe. Angiography revealed a large systemic artery from the descending aorta supplying the basilar segments of the left lower lobe. Continuous thin sliced CT revealed the anatomical details of this anomaly and showed that the tracheobronchial tree had a normal connection with the lung parenchyma. Although the volume of the left lower lobe was reduced, there were no symptoms related to this lesion. Since the splenic lesion was malignant lymphoma limited to the spleen, only splenectomy was performed. In spite of intensive systemic chemotherapy following the operation, there were no pulmonary complications. Although surgery may be necessary in the future, observation alone has been carried out for more than 3 years because of the lack of symptoms and normal pulmonary function. Continuous thin sliced CT was useful in evaluating this anomaly.

Adult↗