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Biomedical subjects

T Okada

Publications and source records attributed to T Okada.

At least 847 records · Page 47Linked to original sources
PubMed1989

[Polyclonal B cell activation induced by Actinomyces viscosus T14V. Responsiveness of human peripheral blood B cells].

We have previously reported that the sonicate extrast from Actinomyces viscosus T 14 V (Av. sup) causes polyclonal B cell activation (PBA) in murine splenic B cells without any T cell assistance. However, there are some reports describing T cell dependency of PBA induced by A. viscosus in human peripheral blood B cells, and it is still controversial whether or not A. viscosus has the capability of exhibiting PBA without the help of T cells. In this report, we examined PBA in human peripheral blood B cells using the same Av. sup which induced T cell independent PBA in murine splenic B cells. The PBA was evaluated in terms of immunoglobulin (Ig) production by means of micro-ELISA method and cell proliferation by incorporation of 3H-TdR after incubation of cells for 5 or 7 days with Av. sup. Human peripheral blood B cells were highly purified by the following methods; The peripheral blood was collected by venipuncture and the peripheral blood mononuclear cells were harvested using gradient centrifugations. These cells were passed through a Sephadex G-10 column, and T cells were eliminated by rosette formation with sheep red blood cells. B cells were highly purified from these T cell-depleted cell populations by panning method with anti-human Ig antibody coated dishes followed by complement-dependent cytotoxisity using monoclonal antibody cocktails consisting of OKT 3, OKT 4 and OKT 8. These highly purified B cells could not respond to T cell mitogens such as PHA.(ABSTRACT TRUNCATED AT 250 WORDS)

Actinomycetales↗
PubMed1989

[Experimental study of periodontal tissue regeneration using biodegradable membranes].

This study was designed to investigate the effect on new attachment formation using a biodegradable membrane as a barrier to the regeneration of periodontal tissue. One-wall wide periodontal osseous defects with exposed root surfaces were prepared in three adult mongrel dogs. After surgical debridement of the periodontal defects, 3 types of biodegradable membranes, [Poly(L-lactic acid); (P-L-LA)] membrane, [Poly(lactic acid-co-glycolic acid); (PLGA)] (81: 19 mole%) membrane and PLGA (50: 50 mole%) membrane, were arranged to cover the denuded root surfaces. Specimen blocks were removed 8 weeks postoperatively for histological evaluation of their effect on the regeneration of periodontal tissue. The results were as follows: 1. Gingival regions containing P-L-LA or PLGA (81: 19 mole%) membranes showed delayed wound healing macroscopically. 2. Almost all P-L-LA membranes were present in the experimental sites failing to be resorbed during the 8-week experimental period. PLGA (81: 19 mole%) membranes were also present but showed with some degree of resorption and fragility, while PLGA (50: 50 mole%) membranes were completely resorbed. 3. This showed that the membranes used in this experiment are possible barriers to the generation of new attachment. It is important to make sure keeping the membrane. 4. There was no relationship between osteogenesis and cementogenesis. It seems that osteogenesis was depressed by membrane shrinkage and the gingival pressure which limited "the regenerative space of bone." 5. Moderate resorption was observed on the root surface, and new cementum was formed at the resorbed surface. 6. Ankylosis was observed between the new cementum and bone at the experimental sites. Newly formed cementum was seen on coronal sections of this area.

Animals↗
PubMed1989

[Distribution of retinal ganglion cells projecting into the nucleus of the optic tract in the rat].

Recent neurophysiological studies have disclosed that the nucleus of the optic tract (NOT) in the pretectum is the first relay station responsible for horizontal optokinetic nystagmus (OKN) both in non-foveate and foveate animals. However, what parts of the retina and what kinds of retinal ganglion cells project their fibers into the NOT have been controversial. In the present study, horseradish peroxidase conjugated with wheatgerm agglutinin (WGA-HRP) was injected into the NOT of rats. The retina and injection sites were processed for the histochemical demonstration of WGA-HRP in order to investigate the distribution of the retinal ganglion cells projecting into the NOT. The present study indicated that visual signals responsible for OKN are mainly conducted from the contralateral retinal ganglion cells, and only from the ventral area of the ipsilateral retina. The retinal ganglion cells projecting into the NOT ipsilateral to the injection site were larger than those on the contralateral side. Large retinal ganglion cells existed on the peripheral areas including ipsilateral ventral area. The density of the ventral ganglion cells of the retina contralateral to the injection site was lower than that in other areas of retina, and the density of the ventral ganglion cells ipsilateral to the injection site tented to be greater than that on the contralateral side. Since the ventral area of retina corresponded to the upper visual field in front of the nose, it may receive visual signal of OKN and fire OKN. In conclusion, visual signals responsible for OKN are conducted through the retinal ganglion cells mainly contralaterally, and only from the ventral area of the retina ipsilateral to the injection site.

Animals↗
PubMed1989

[Assessment of bleomycin-induced pulmonary fibrosis by bronchoalveolar lavage].

To elucidate the pathogenesis of adult respiratory distress syndrome (ARDS), bleomycin is often used to induce lung injury because of is acute inflammatory and late fibrogenic effects on the lung. This study was undertaken to determine if fibroblast growth factors or suppressive factors might exist in bronchoalveolar lavage fluid (BALF) when acute lung injury is induced by bleomycin in rats. In the experimental group, 1.5 U of bleomycin was administered intratracheally, whereas in the control group, saline solution was given. In both groups, rats were sacrificed serially up to 4 wks. In each rat, bronchoalveolar lavage was done three times using an aliquot of 5 ml saline solution. BALF was centrifuged to obtain cells and supernatants which were further fractionated by gel-filtration. Fibroblast stimulatory and inhibitory activities were evaluated by [3H]-thymidine incorporation by fibroblasts. In the experimental group, the recovered cell count increased threefold compared with the control group and most of the increase was attributed to the increase of neutrophil. The fraction whose molecular weight is about 20,000 potentiated the [3H]-thymidine incorporation by fibroblast and its peak activity was found on the 5th day after BLM administration. On the other hand, the fraction of small molecular weight (less than 1,000) showed inhibitory activity which did not change throughout the study period. These results suggest that the imbalance between the fibroblast stimulatory and inhibitory activities after the acute lung injury may have a key role to develop pulmonary fibrosis.

Animals↗
PubMed1989

Occlusion of small hepatic veins associated with systemic lupus erythematosus with the lupus anticoagulant and anti-cardiolipin antibody.

We report the case of a woman with lupus anticoagulant-positive systemic lupus erythematosus who developed small hepatic vein occlusion. Since the age of 34, she had been known to have hepatomegaly. A definitive diagnosis of systematic lupus erythematosus was made eight years later. Histological evaluation of the liver biopsy specimen was not fully diagnostic of prominent hepatomegaly during this period. Occlusion of the small hepatic veins was confirmed by hepatic venography, but the lumen of the large hepatic veins showed a smooth appearance. The lupus anticoagulant and anti-cardiolipin antibody were both positive. Since a high incidence of thromboembolic diseases in patients with the lupus anticoagulant or anti-cardiolipin antibody has been reported, the presence of this type of anticoagulant may provide an explanation for hypercoagulability and subsequent development of hepatic vein thrombosis in this patient. This is the first report of a patient with systemic lupus erythematosus who developed an occlusion of small hepatic veins attributable to the lupus anticoagulant and anticardiolipin antibody. This case suggested that a systematic search for hepatic vein occlusion should be made in patients with systemic lupus erythematosus who have developed inexplicable hepatomegaly, especially in those with positive tests for the lupus anticoagulant and/or anti-cardiolipin antibody.

Adult↗
PubMed1989

[A clinical evaluation of clarithromycin in the treatment of pediatric infections].

Clarithromycin (TE-031, A-56268) granules were used to treat various infections in the pediatric field and the results obtained are summarized as follows. 1. TE-031 was administered to a total of 10 patients (5 cases of enteritis, 4 cases of bronchitis and 1 case of tonsillitis). Clinical efficacies were excellent in 6 patients and good in 4 with an efficacy rate of 100%. 2. Neither side effects nor abnormal laboratory test values were observed. There was no rejection of drug disturbing the therapy.

Age Factors↗
PubMed1989

[Combination with medroxyprogesterone acetate and chemotherapy making possible complete removal of uterine corpus carcinoma].

A case of uterine corpus carcinoma (stage III) after surgical resection of her primary lesion was treated with a medroxyprogesterone acetate (MPA) and PAE (CDDP, adriamycin and etoposide) regimen. The patient has been given MPA during a three-month period and received four courses of PAE regimen. The residual tumor was decreased and removed completely at the second-look operation. Pathologically, the carcinoma cells were clearly changed in loss of atrophy or degeneration by MPA or PAE regimen. After the second-look operation, the patient underwent 4 courses of PAE regimen and was given MPA continuously. We have not recognized any recurrence of carcinoma for seven months after the second look operation.

Adenocarcinoma↗
PubMed1989

[A quantitative evaluation of brain computerized tomography in children using color image analyzer].

We attempted the quantitative analysis of brain computerized tomographic scans in children using Color Image Analyzer. A consecutive series of 167 computerized tomographic scans were reviewed. Areas of subarachnoid spaces, cavums, ventricles and cerebellums were measured on three slices: A slice is at the level of head of caudate nucleus, anterior horn of lateral ventricle and third ventricle. B slice is at the level of body of lateral ventricle. C slice is at the level of sella turcica and pons. We investigated these values compared with Evans ratio, Cella Media Index, cerebellar atrophy score and visually evaluations. Serial brain CT scans of eight patient with infantile spasms were also evaluated for the assessment of the brain shrinkage after ACTH therapy. 1) The ratios of the subarachnoid space/the intracranial area on A and B slices (SAS A%, SAS B%) were significantly higher in the patients of severe brain atrophy. 2) There were linear relationship between Evans ratio and SAS A% (r = 0.405, p less than 0.001), Cella Media Index and the ratio of the lateral ventricles/the intracranial areas on B slice (r = -0.501, p less than 0.001), and the cerebellar atrophy score by Une and SAS C% (r = 0.369, p less than 0.001). 3) In the normal patients, the values of SAS A% and SAS B% were much greater in less than 1.5 years old children. These results suggest that the trend of CT findings related to age may reflect physiological changes of the space between the skull and the brain with age. 4) Brain shrinkage after ACTH therapy was more pronounced in the subarachnoid space than the ventricle.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Cytogenetic evidence for a clonal disorder involving CFU-GEMM, BFU-E and CFU-C in patients with myeloproliferative disorders.

We grew multilineage hemopoietic colonies in vitro from 4 patients with myeloproliferative disorders (MPD) having chromosomal aberration, and performed cytogenetic analysis of single CFU-GEMM, BFU-E and CFU-C-derived colonies on Day 14 of culture. In Patient 1 with acute myelofibrosis, CFU-GEMM and BFU-E colonies had only a 47, XX, +C karyotype. In Patient 2 with polycythemia vera, CFU-GEMM, BFU-E and CFU-C colonies all showed the same abnormal karyotype of 46, XY, -12, +der(12)t(1;12). Patients 3 and 4 had primary myelofibrosis, and their respective karyotypes were 46, XY, 13q- and 46, XX, -6, +der(6)t(1;6) in CFU-GEMM, BFU-E and CFU-C colonies. In these 4 patients, the karyotype of bone marrow or circulating mononuclear cells was identical to that of hemopoietic colonies. These results indicate a clonal origin of MPD at the level of CFU-GEMM.

Adult↗
PubMed1989

[Clinico-pathological studies of alcoholic liver disease, especially on the diagnostic significance of endogenous bile acid tolerance test].

Endogenous bile acid tolerance test was performed in 88 patients with alcoholic liver disease and results obtained were compared with histological features in their liver biopsy specimens. An increase of serum fasting total bile acid (FTBA) and maximum total bile acid (MTBA) was closely reflected the degrees of hepatic fibrosis and they were seemed to be useful for differential diagnosis and clinical observation of the alcoholic liver disease. We have been reported the criteria of the grading for bile acid tolerance test at Inuyama Symposium in 1977. With the use of this criteria, we applied it to alcoholic liver disease. The results of bile acid tolerance test were normal in patients with ALF mild, fatty liver and no remarkable change, these were slightly abnormal in patients with ALF moderate and severe, these were severe abnormal in patients with ALC. Bile acid tolerance test is a sensitive liver function test. However, this method is too complex for clinical use. Therefore, we recommend to use the serum bile acid level at 60 minutes after the yolk loading (60min-TBA), because we found 60min-TBA was almost the same as MTBA and accurately reflect the liver morphology. So, we concluded measurement of FTBA and 60min-TBA were adequate, especially in outpatients, to evaluate the progress of alcoholic liver disease.

Adult↗
PubMed1989

Cinevideodensitometric quantification of relative coronary arterial stenosis: application to evaluating candidates for percutaneous transluminal coronary angioplasty.

As an alternative to visual interpretations of subjects' angiograms, coronary arteries dilated by percutaneous transluminal coronary angioplasty (PTCA) were evaluated using cinevideodensitometry, and the results were compared with those obtained by the edge detection method. Coronary arteriograms were obtained in various projections and suitable frames were selected for analysis. The frames were transformed to digitized images (512 X 512 X 8 bits) with an image analyzer (MIPRON 1), and cinevideodensitometric and edge detection analyses were performed. Phantom models of various shapes were opacified with contrast medium and were used to test our system. The cineangiograms of 58 patients with ischemic heart disease, 28 of whom had underwent PTCA, were analyzed. A highly linear correlation was observed between the cross-sectional areas of the phantoms and the summed gray levels measured using cinevideodensitometry. Percent area stenosis evaluated by the two methods was accurate and reproducible in measuring the symmetrical stenosis models. However, for the model of asymmetrical stenosis, the measurement by the edge detection method differed according to various projections. Similar results were obtained measuring asymmetrical stenosis in the right coronary artery in vivo in various projections. Based on these experimental results, coronary stenoses dilated by PTCA were evaluated. Prior to PTCA, coronary arterial stenosis measured using the two methods closely approximated each other. However, following PTCA, there were discrepancies between the measurements by the two methods in six cases. This can be accounted for by asymmetrical changes in a luminal cross-section, which cannot be accurately assessed using the edge detection method in single plane projection. In conclusion, cinevideodensitometric measurements of relative coronary arterial stenosis were objective, accurate, and reproducible. According to cinevideodensitometric analysis, eccentric lesions can be measured using a single projection, and tracing arterial borders is unnecessary. It is a useful means in measuring quantitatively the degree of dilatation of coronary arterial stenosis accomplished by PTCA.

Angiography↗
PubMed1989

Effects of zopiclone on sleep spindles studied with an improved waveform recognition method.

The effects of zopiclone on sleep spindles were analyzed in six normal volunteers by using an improved waveform recognition method. The appearance rate of spindles during stage 2 of NREM sleep showed a significant increase on the drug night, which returned to the baseline on the withdrawal night. The mean duration of spindles was significantly prolonged on the drug night. No definite changes were observed in the average spindle frequency. The mean amplitude of spindles had a tendency to decrease on the drug night. On the withdrawal night, the mean amplitude decreased significantly compared with that of the baseline. Our results indicate that zopiclone is one of the spindle enhancing drugs, and that its property resembles that of benzodiazepines.

Adult↗
PubMed1989

[Sleep disturbances complicated by surgical stress; a questionnaire survey of 50 patients].

A questionnaire survey of sleep disturbances was undertaken in 50 adult surgical patients to examine the prevalence of insomnias complicated with surgical stress. The survey about nocturnal sleep conditions was performed for consecutive four nights from two days before surgery. Defining early awakenings, difficulty of initiating or maintaining of sleep as manifestations of insomnias, the incidence of insomnias amounted to 72.9% on the night of two days before surgery, 72.0% on the night before surgery, 86.0% on the night of surgery, and 86.6% on the first night after surgery. High incidence of sleep disturbances complicated with surgical stress is noteworthy in the field of perioperative care.

Adult↗
PubMed1989

[Therapeutic effectiveness of vitamin D3 in patients with myelodysplastic syndromes, leukemias and myeloproliferative disorders].

We tried to treat 13 patients with myelodysplastic syndromes (MDS), leukemias and myeloproliferative disorders, with alfacalcidol for their hematological improvement. Eight of them had MDS, 2 acute leukemia (M3, M4), 1 chronic myelogenous leukemia and 2 primary myelofibrosis. All patients were untreated except for 3 patients (PASA, RAEB, AML-M4) who had been treated with mepitiostane, prednisolone and BH.AC-AMP regimen, respectively, prior to alfacalcidol therapy. All patients received alfacalcidol orally for at least one month. The dosage of alfacalcidol ranged from 0.25 to 10 micrograms/day, and the medicine was administrated intermittently when the dosage exceeded 6 micrograms/day to prevent hypercalcemia. The therapeutic effectiveness of alfacalcidol was evaluated according to a criteria by Koeffler (Cancer Treat Rep 69: 1399, 1985) with minor modifications. Three patients (PASA, RAEB, CMML) showed partial response, 3 (RAEB, RAEB in T, AML-M4) minor response and rest of the patients did not respond. The hematological improvement of 6 responders was transient (from 1 to 2 months), however, one patient (PASA) is still responding to alfacalcidol therapy (0.25 microgram/day) for over 12 months. The dysplastic features of hemopoietic cells in the bone marrow showed no noticeable change during the hematological improvement in these responders, suggesting the improvement was obtained as a result of alteration in the proliferation or differentiation of neoplastic clone. None of 13 patients developed hypercalcemia. One patient (AML-M4) became excitable on high dose alfacalcidol (10 micrograms/day). In conclusion, alfacalcidol therapy is effective in some patients with MDS or leukemias and appears worthy especially in the clinical state in which chemotherapy is not indicated.

Adult↗
PubMed1989

[Is massive fluid load indispensable for the parturient immediately before regional anesthesia?].

One hundred healthy parturients scheduled for elective cesarean section were studied prospectively. Fifty patients received spinal anesthesia with 12mg of hyperbaric tetracaine and were defined as the spinal group. Other fifty patients received epidural anesthesia with 300mg of lidocaine and were defined as the epidural group. A half of patients in each group were given 1,000ml of Ringer's lactate immediately before the regional anesthesia (prehydrated). Rapid hydration was not given to another half of them (non-prehydrated). In the spinal group, ephedrine administration was needed significantly less frequently for prehydrated patients than for non-prehydrated ones. And the mean dose of this drug for prehydrated patients was significantly less than that for non-prehydrated ones. In the epidural group, though prehydration tended to prevent maternal hypotension, neither rate of ephedrine administration nor mean doses of this drug showed any significant difference between prehydrated and non-prehydrated patients. Prehydration did not improve significantly neither acid-base balances of umbilical arterial and venous blood nor Apgar scores of the neonates in either group. We conclude that massive fluid load is not indispensable immediately before the regional anesthesia for the parturient. Furthermore, because this method is not reliable, its advantages and disadvantages including the possibility of enhancing pulmonary edema should be evaluated.

Adult↗
PubMed1989

[The results of bypass with the BioPump in the surgery of traumatic rupture of the thoracic aorta without heparin].

In surgery of the traumatic rupture of descending thoracic aorta, external shunt without systemic heparinization is commonly employed to avoid the bleeding of other injured organs as well as the ischemic injury of spinal cord. However, it provides no means of controlling the flow. We employed the BioPump without heparinization in 2 cases of traumatic rupture of descending thoracic aorta and additional 2 cases of aneurysm of thoracic aorta. Significant platelet loss occurred immediately after operation, however, there was no postoperative evidence of the organ failures due to microembolization. Heparinless bypass with the BioPump is considered to be safe and simple as an adjunct means in surgery of the traumatic rupture of thoracic aorta.

Adolescent↗