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Biomedical subjects

T Otsuka

Publications and source records attributed to T Otsuka.

At least 235 records · Page 13Linked to original sources
PubMed1993

Hypercapnia slightly raises blood volume and sizably elevates flow velocity in brain microvessels.

The increase in local cerebral blood flow (LCBF) caused by hypercapnia may be mainly accomplished by raising the velocity of plasma and/or red blood cell (RBC) flow through the microvessels and not by perfusing more capillaries. This suggestion was tested in awake rats exposed to 8% CO2 and in control rats. LCBF was measured by the 14C-labeled iodoantipyrine method. The volume of blood in small parenchymal microvessels was estimated from the distribution spaces of 125I-labeled serum albumin (RISA) and 55Fe-labeled RBCs. Hypercapnia elevated LCBF 2.0- to 3.5-fold in the 40 brain areas studied, marginally raised the RBC spaces, and significantly increased the RISA and whole blood distribution spaces (approximately 25 and 19%, respectively). These changes in microvessel distribution volumes could be the result of perfusing a slightly larger fraction of capillaries (recruitment), increasing microvessel diameter somewhat, or both. With hypercapnia, the mean transit times fell to approximately 45% of control, which indicated that LCBF was mainly increased by raising the velocity of RBC and plasma flow through already perfused microvessels. Overall, few, if any, capillaries or other microvessels were recruited by hypercapnia.

Animals↗
PubMed1993

Nicotine increases microvascular blood flow and flow velocity in three groups of brain areas.

To examine the mechanism of local cerebral blood flow (LCBF) elevation, nicotine (1.75 mg/kg sc) was administered to rats, and LCBF plus the distribution spaces of radiolabeled albumin (RISA) and red blood cells (RBC) in parenchymal microvessels were measured throughout the brain. Microvascular blood spaces and transit times were calculated from the data. From 1.5 to 3 min after nicotine administration, LCBF was raised by 40-150% in 16 of the brain areas and unaltered in the remaining 28 areas. The affected structures included parts of the visual-auditory, sensorimotor-cortical, and interpeduncular systems. RBC spaces were not changed by nicotine treatment. RISA and blood spaces were increased slightly but not significantly in some of the LCBF-affected areas but nowhere else. Nicotine seemingly elevates LCBF in the affected areas mainly by increasing linear velocity of flow through the microvascular beds. In agreement with this, mean transit time, which is inversely related to velocity, was decreased from 0.3-0.5 to approximately 0.2 s in the microvascular systems of the nicotine-affected areas.

Animals↗
PubMed1993

Differences in response of patient's blood cells with bronchial asthma to diverse house dust mite allergens by histamine release assay.

A HPLC method was developed for the determination of histamine released from washed blood cells of allergic patients after exposure to allergens in the presence or absence of plasma. The blood cells used were preserved in a vital state at 4 degrees C during at least 6 hours after blood-collecting. The responses of blood cells to an appropriately diluted series of a mite feces extract (Dff) solution were evaluated in three patient's groups (68 cases of hyposensitized, 59 cases of newly visited and 44 cases of the others) with bronchial asthma. Washed blood cells from the hyposensitized groups had a tendency to release histamine easily even with lower concentration of the Dff solution. Both the sensitivities of washed blood cells to Dff or mite body extract (Dfb) and the responses of the cells to diverse antigens in neither extract differed largely in individual cases. The titer of blocking antibody could be expressed as the amount proportional to the concentration of Dff or Dfb.

Allergens↗
PubMed1993

[Immunoblastic lymphadenopathy (IBL)-like T cell lymphoma associated with granulocytopenia and autoimmune hemolytic anemia].

A 65 year-old woman was admitted in May 1990, because of fever, generalized lymphadenopathy and eruption. Laboratory examination showed granulocytopenia, polyclonal hypergammaglobulinemia, positive Coombs' test, positive cold antibody and positive anti-E erythrocyte antibody. 7 days after admission autoimmune hemolytic anemia developed. The appearance of the anti neutrophil leukocyte antibody was suspected because of the absence of the segmented neutrophils in marrow specimen. Histological findings of the biopsied lymph node and the marker study of the tumor cell disclosed IBL-like T cell lymphoma. The patient was treated with G-CSF and VEPA chemotherapy. Granulocytes increased and she showed marked symptomatic improvement with complete remission. Our case showed various clinical pictures with hemolytic anemia and granulocytopenia, which could be based on the autoimmune mechanisms.

Aged↗
PubMed1993

[Analysis of proliferating cell nuclear antigen and nucleolar organizer region in testicular tumors].

Immunohistochemical staining using the monoclonal antibody of proliferating cell nuclear antigen (PCNA) and argyrophilic nucleolar organizer region associated protein (AgNOR) staining were performed on 28 paraffin-embedded testicular tumors, and their correlation was assessed according to histological type, clinical staging and tumor markers. PCNA positive rates and AgNOR numbers in nuclei were 57.9%, 4.38 in seminomas, 63.4%, 5.79 in embryonal carcinomas, 37.7%, 2.63 in teratomas, 61.3%, 4.43 in yolk sac tumors, 79.5%, 7.12 in choriocarcinomas, and 20.9%, 3.03 in cells of the normal seminiferous tubule, respectively. In pure seminomas, the PCNA positive rates and AgNOR numbers of the stage II to III group (72.6%, 4.75) were higher than those of the stage I group (47.8%, 3.67), but there was no significant difference between the two groups. There was a significant correlation between PCNA positive rate and AgNOR number in all specimens (r = 0.76, p < 0.002). These findings indicate that PCNA and AgNOR are suitable indicators for proliferative activity of testicular tumors.

Adult↗
PubMed1993

[A case of systemic lupus erythematosus who developed nodular shadows in the lung in parallel with the disease activity].

A 35-year old woman was admitted to our hospital in April 1991 due to the appearance two nodular shadows on chest X-ray. The patient's past medical history was as follows; In 1986, she developed polyarthralgia, facial eruptions and Raynaud's phenomenon which was treated with prednisolone. In 1988, investigations revealed proteinuria where by the diagnosis of SLE complicated with lupus nephritis was established. Subsequently, treatment with cyclophosphamide was carried out. However, in January 1991, there was further increase in urine proteins in accompaniment with systemic eruptions. In addition, laboratory findings showed an increasing titre of anti-DNA antibody and decreasing serum compliments. In April 1991, as indicated before, a chest X-ray revealed nodular shadows in the right upper and lower lung fields, therefore, a transbronchial lung biopsy was performed. The histology revealed inflammatory infiltrates in the bronchoalveolar tissue, fibrosis of the septa- and exudates in the alveolar space. These findings suggested fibrosing alveolitis. It was true considered that these lesions in the lung were associated with the exacerbation of SLE. In view of this, the dose of prednisolone was increased to 60 mg/day. Consequently, the nodular shadows regressed and the clinical course of SLE improved. It is well appreciated that some patients with SLE develop variable pulmonary involvement, however, this case is of great interest due to the fact that multiple nodular shadows on chest X-ray are very rare in SLE.

Adult↗
PubMed1993

[Thoracoscopic partial resection of the lung by use of Nd-YAG laser and standard suturing technique].

The patient was a 62-year-old woman who was referred to our department for bilateral diffuse abnormal shadows along with a sigmoid colon cancer that had been resected one month previously. Thoracoscopic partial resection of the left S8 region was performed. Nd-YAG laser with a contact tip was used for the resection. Hemostasis at the bed of the resection was assured by applying a free laser beam to oozing and non-coagulated surface. Additionally, the resected end was closed by standard continuous double over-and-over sutures in order to minimize the air leakage. Endo-Bulldog clamp facilitated the operation, minimizing hemorrhage from the resected end. This device can clamp any part of the lung and save one percutaneous puncture site necessary for thoracoscopic procedures. Postoperative course was uneventful. Pathological diagnosis was reported as an alveolar cell carcinoma of the lung.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1993

[Production of leukotrienes in rat Kupffer cells and hepatocytes by various inducers].

In order to verify whether rat hepatocytes are capable of producing leukotrienes, Percoll density gradient centrifugation to fractionize rat hepatocytes and a radioimmunoassay of leukotrienes in the reacting solution have been performed. Also, investigated was effect of retinol (Vitamin A) on inducing the production of leukotrienes in rat Kupffer cells and hepatocytes. Incubation with endotoxin (10 micrograms/ml) for 30-60 minutes induced the production of leukotrienes in rat Kupffer cells but did not induce any such production in rat hepatocytes. On the other hand, arachidonic acid (2-20 microM) or linoleic acid (10-50 microns) did induce hepatocytes to produce leukotrienes in a dose-dependent manner. Fifteen minutes of pre-incubation with 10(-8) M of retinol inhibited an endotoxic induction of leukotrienes production in rat Kupffer cells, whereas it did not inhibit an arachidonic acid induction in rat hepatocytes. Based on these results, we have concluded that a hepatic tissue injury during sepsis is probably mediated by leukotrienes produced by the Kupffer cells and its inhibition is the mechanism of tissue protective effect of retinol. However, in further severe state even the hepatocytes may produce leukotrienes and as a consequence, a widespread destruction of hepatic tissue will occur.

Animals↗
PubMed1993

Osteosarcoma with deeply eosinophilic rhabdomyoblast cells in a lung metastatic focus. A case report.

In a ten-year-old boy with left femoral osteosarcoma, the diagnosis of osteosarcoma was established through bone biopsy. Chemotherapy was administered, but episodes of recurrence and metastasis occurred. In July 1989, a second lung metastatic focus was resected. Histopathologic examination of this metastatic focus showed widespread cross-striation together with osteoid formation. A comparable case seems not to have been reported in the literature.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Bone marrow microenvironment of patients with systemic lupus erythematosus.

In an attempt to clarify the hematologic abnormality in systemic lupus erythematosus (SLE), we studied the bone marrow microenvironment of 8 women with this disease. The number of fibroblast colonies was similar to that of healthy control individuals. Culture supernatants of monocytes obtained from the patients with SLE showed a diminished production of the hemopoietic growth factor required to stimulate bone marrow fibroblasts. As the activity of the humoral factor released from SLE monocytes was diminished, such a reduction may play a role in the pathogenesis of the hematologic abnormality seen in SLE.

Bone Marrow↗
PubMed1993

[Study on the inhibitory effect of oral granisetron against nausea/vomiting induced by cytosine arabinoside containing chemotherapy for tumors in the hematopoietic organs].

We investigated the antiemetic effect, safety and usefulness of granisetron tablet on nausea/vomiting induced by cytosine arabinoside (Ara-C) in the chemotherapy for tumors in the hematopoietic organs. Out of 52 cases with malignant tumors in the hematopoietic organs including acute leukemia, 30 in granisetron group had no antiemetic treatment, were evaluated for the clinical efficacy of granisetron and 22 in control group. Their chemotherapies were combination therapy with Ara-C and daunorubicin (DNR), Ara-C and mitoxantrone (MIT), or Ara-C and etoposide (VP-16). In the trial, the dosage of granisetron tablet was 2 mg once a day, and the drug was given before each chemotherapy for 6 consecutive days. In clinical efficacy the effective rate of granisetron (the percentage of cases in which the trial drug was assessed as "Remarkably effective" or "Effective") was more than 80% on each day of administration. There was no adverse event. As the abnormal laboratory test value, only 1 case tested positive in urine protein, whose causal relation to the trial drug was judged as "Unassessable". Granisetron was judged as "Safe" in 31 out of 32 cases (96.9%). In terms of usefulness, the drug was rated "Extremely useful" or "Useful" in 26 out of 30 cases (86.7%). The above results have shown that granisetron tablet, when administered orally once daily at a dose of 2 mg, has an excellent antiemetic effect, and is a safe and useful drug.

Administration, Oral↗
PubMed1993

Transfection of interferon-gamma gene in a mouse bone marrow stromal preadipocyte cell line causes apoptotic cell death.

It has been reported that bone marrow and serum of patients with aplastic anemia or chronic myeloproliferative disorders contain an abnormal concentration of cytokines. In the present study, we tried to isolate mouse bone marrow stromal cell lines that were stably transformed with a variety of cytokine genes and that expressed them constitutively. From mouse bone marrow stromal cell lines MBA-1, MBA-13, and 14F1.1, we isolated clones secreting interleukin-3 (IL-3), IL-4, granulocyte-macrophage colony-stimulating factor (GM-CSF), or granulocyte (G)-CSF. Interferon-gamma (IFN-gamma)-producing stable transformants could not be established from 14F1.1 cells in spite of repeated transfection trials. At early stages of transfection, 14F1.1 cells did secrete IFN-gamma; however, exogenously added mouse IFN-gamma could not inhibit 14F1.1 cell growth. We discovered that chromosomal DNA isolated from 14F1.1 after transfection with the mouse IFN-gamma gene was fragmented. This is characteristic of cells undergoing apoptotic cell death. DNA fragmentation was also observed in 14F1.1 cells transfected with the human IFN-gamma gene. These results indicate that intracellular IFN-gamma induces apoptotic cell death of 14F1.1 stromal cells.

Adipocytes↗
PubMed1993

Immuno-reactive human epidermal growth factor (h-EGF) in rheumatoid synovial fluids.

The immuno-reactive human epidermal growth factor (h-EGF) level, measured by a sensitive enzyme immunoassay, was significantly higher in synovial fluids or synovial tissue extracts from 89 patients with rheumatoid arthritis (RA) than in those from 53 patients with osteoarthritis. RA synovial immuno-reactive h-EGF was predominantly of a low molecular weight form (LMW h-EGF) on gel filtration chromatography. Furthermore, in the RA group, the synovial immuno-reactive h-EGF correlated positively with C-reactive protein, an acute-phase reactant, in the blood examination and with synovial immunoglobulin M. These results suggest that synovial h-EGF is specifically produced by RA synovium from the initial stage of arthritis, and that the measurement of synovial h-EGF serves as an early indicator to appraise the RA activity. A pathogenesis of RA including growth factors and growth inhibitory factors are discussed.

Adult↗
PubMed1993

[Continuous intracarotid infusion of mannitol in severe head injury].

The clinical significance of continuous intracarotid infusion of a small dose of mannitol (ICI of mannitol) was discussed. Eighteen patients suffering from severe head injury with Glasgow coma scale (GCS) less than 6 were treated by ICI of mannitol for the improvement of raised intracranial pressure (ICP). In all of these 18 cases, conventional venous administration of mannitol could not be carried out, because of the unstable vital signs due to hypovolemic shock such as multiple trauma or disturbance of serum sodium and potassium levels. This method requires that a 20% mannitol solution be directly and continuously administered to the bilateral common carotid artery. The ICP 6 hours after the beginning of ICI of mannitol was significantly lower than the ICP just before the treatment. The total amount of excretion of the sodium and potassium through the urine every hour decreased significantly after this method was used. It was also noticed that this method was very suitable for stabilizing the vital signs in cases which had unstable vital signs such as hypovolemic shock. These findings suggested that ICI of mannitol has an advantage over the conventional venous administration of mannitol in cases which had to have correction of serum electrolyte or which had unstable vital signs.

Adolescent↗