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Biomedical subjects

J Tanaka

Publications and source records attributed to J Tanaka.

At least 433 records · Page 24Linked to original sources

[A clinical study of motor activity and neural control of human sphincter of Oddi in post-operative state of cholecystocholedocholithiasis].

Intraluminal pressure of sphincter of Oddi (SO) was measured in awake patients who had undergone cholecystectomy and T-tube drainage for cholecystocholedocholithiasis. Pressure measurement was carried out using microtransducer which was inserted through sinus tract under cholangioscopy after removing T-tube. Mean value of the basal pressure was 12.0 +/- 1.5 mmHg, the amplitude of the phasic contraction was 55.2 +/- 4.4 mmHg and the frequency of the phasic contraction was 4.2 +/- 0.3 cycle/min. Intravenous administration of caerulein or atropine caused marked decrease in the amplitude and the frequency of the phasic contraction of SO, whereas pentazocine caused marked increase in the basal pressure, the amplitude and the frequency of the phasic contraction of SO. Naloxone alone did not affect the phasic contraction of SO, but it reduced the increased amplitude and frequency of the phasic contraction of SO caused by pentazocine. In conclusion, cholinergic nerves, excitatory nerves mediated by opioid receptors and non-cholinergic non-adrenergic inhibitory nerves may modulate spontaneous motor activity of human sphincter of Oddi.

Adult↗

Effect of daily subcutaneous administration of recombinant erythropoietin on chronic anemia in rheumatoid arthritis.

Mean (+/- SD) serum erythropoietin (EPO) levels were 18.6 +/- 5.6 mU/ml in 180 normal Japanese subjects. Serum EPO levels were elevated with a negative correlation on a log scale (r = -0.864, P < 0.005) to hematocrit (Ht) values in anemic patients not associated with rheumatoid arthritis (RA) or chronic renal failure (CRF). Serum EPO levels in patients with RA (31.6 +/- 16.4 mU/ml) were relatively lower than those in normal subjects and anemic patients without RA or CRF when matched for comparative Ht values. Seven anemic patients with RA were treated by daily subcutaneous (sc) injection of recombinant EPO (rEPO, 500-1,000 U/day) for 4 weeks. The patients had initial Ht values of 25.1% or less and maintained stable clinical status. The treatment with rEPO raised serum EPO levels (53.8 +/- 15.2 mU/ml, P < 0.05), which resulted in an increase in Ht values (more than 3%) in 6 out of 7 patients with RA. The mean (+/- SD) Ht values at the end of the treatment with rEPO (500-1,000 U/day) were greater than those before the treatment in the 7 patients with RA (28.5 +/- 4.6 vs. 22.7 +/- 2.5%, P < 0.05). These findings suggest that chronic anemia associated with RA may be corrected by daily sc injection of a small dose of rEPO.

Adult↗

Hyperplastic polyps following treatment of acute gastric ulcers.

Although hyperplastic polyps are the most common polyps of the stomach, the etiology of these polyps is not completely understood. We report a 61-year-old woman who developed gastric hyperplastic polyps following acute gastric lesions. She was admitted for endoscopic injection sclerotherapy of esophageal varices. After the end of sclerotherapy, acute gastric lesions developed. For treatment of the lesions, omeprazole was used for 8 weeks followed by famotidine for 8 weeks. At the end of the treatment, she developed multiple gastric hyperplastic polyps, suggesting that acute gastric lesions and/or treatment of the gastric lesions are related to the development of hyperplastic polyps in the stomach.

Esophageal and Gastric Varices↗

Nonsurgical treatment of unruptured intracranial vertebral artery dissection with serial follow-up angiography.

The question of whether unruptured intracranial vertebral artery dissections should be treated surgically or nonsurgically still remains unresolved. In this study, six consecutive patients with intracranial vertebral artery dissection presenting with brain-stem ischemia without subarachnoid hemorrhage (SAH) were treated non-surgically with control of blood pressure and bed rest, and five received follow-up review with serial angiography. No further progression of dissection or associated SAH occurred in any of the cases, and all patients returned to their previous lifestyles. In the serial angiograms in five patients, the findings continued to change during the first few months after onset. Four cases ultimately showed "angiographic cure," while fusiform aneurysmal dilatation of the affected vessel persisted in one case. In one patient, arterial dissection was visualized on the second angiogram despite negative initial angiographic findings. These results indicate that intracranial vertebral artery dissection presenting without SAH can be treated nonsurgically, with careful angiographic follow-up monitoring. Persistent aneurysmal dilatation as a sequela of arterial dissection seemed to form a subgroup of fusiform aneurysms of the posterior circulation. These aneurysms may be prone to late bleeding and may require surgical treatment.

Adult↗

Syntheses of o-methacryloyl-N-acyl tyrosines and their adhesiveness to un-etched human dentin.

O-Methacryloyl-N-acyl tyrosines (MAATY) having acyl groups with the various chain length were synthesized and the strength of bonding agents, consisting of MAATY as an adhesive monomer, to unetched human dentin was studied to elucidate the relationship between the molecular structure of MAATY and its adhesive characteristics. Increasing the flexibility of the carboxyl group of tyrosine favors the interaction with the tooth substrate, causing strict bonding. Also, the properties of the neighboring carboxyl group, i. e., steric hindrance and hydrophobicity, hydrophobic-hydrophilic balance in the monomer, and shrinkage of the monomer at copolymerization, are considered important. Especially, steric hindrance of the substituted group neighboring the carboxyl group of tyrosine would play an extremely important role in the adhesion of O-methacryloyl-N-octanoyl tyrosine. The maximum tensile bond strength was obtained with a bonding agent consisting of O-methacryloyl-N-hexanoyl tyrosine (15 mol%) and hydroxyethyl methacrylate (85 mol%), and the strength (4.75 MPa) was the maximum in all methacrylates with phenylalanine as a bone structure.

Acid Etching, Dental↗

Cytokines involved in graft-versus-host disease.

Graft-versus-host disease (GVHD) is one of the major complications which should be resolved to improve the survival rates in allogeneic bone marrow transplantation (BMT). Recently, several cytokines have been identified, suggesting that they form a cytokine network and play an important role in immune system and hematopoiesis. Among several cytokines, it has been reported that tumor necrosis factor alpha (TNF alpha) and interleukin-6 (IL-6) are mainly involved in GVHD. In the present report, we analyzed the role of cytokines in GVHD. When we measured serum cytokine levels, IL-6, interferon gamma (IFN gamma), and TNF alpha levels were increased prior to the onset of acute GVHD. For chronic GVHD, a similar pattern of cytokine increment was observed. Interestingly, these cytokines appeared to interact synergistically to induce clinical GVHD, suggesting that none of those cytokines does not function solely. Reverse transcriptase-polymerase chain reaction (RT-PCR) showed that increased IL-1 beta mRNA expression was also observed in acute GVHD in addition to increased IL-6 and TNF alpha mRNA expressions. Unexpectedly, no increased IL-2 levels were observed in both assays. In hyperacute GVHD, only IL-6 level was increased. However, in vivo administration of IL-6 into allogeneic bone marrow chimeras did not induce severe GVHD. Therefore, some other factors also appeared to be involved in inducing hyperacute GVHD. Furthermore, it is important to consider the role of inhibitory cytokines such as transforming growth factor beta (TGF beta) or IL-10.

Animals↗

[A case of pontine hematoma with Foville's syndrome in childhood].

We reported a surviving case of 6-year-old boy with pontine hematoma. He complained of headache as an initial symptom and developed progressively Foville's syndrome with impairments of the IX-XII cranial nerves. Although brainstem tumor was suspected initially using CT scan, MRI revealed the existence of hematoma in the ventromedial pons. During the first 4 months of his clinical course, Gd-DTPA did not demonstrate any enhancement in that lesion. However, hemangiomatous lesion was suspected by subsequent serial MRIs with positive Gd-DTPA enhancement. Using conservative treatment including oral corticosteroids, all the neurological deficits disappeared in several months and he did not show any recurrence of clinical signs for 3 years. It was suggested that MRI was very useful in the differential diagnosis and the follow-up of hematoma in the posterior fossa.

Accessory Nerve↗

Cytokine gene expression by concanavalin A-stimulated peripheral mononuclear cells after bone marrow transplantation: an indicator of immunological abnormality due to chronic graft-versus-host disease.

The response of IFN-gamma, IL-2 and IL-5 mRNA expression to the stimulation of concanavalin A (Con A) in peripheral blood mononuclear cells (PBMC) after bone marrow transplantation (BMT) was analyzed using reverse-transcriptase polymerase chain reaction (RT-PCR) to assess the recovery of T cell function. The subjects were 23 patients undergoing allogeneic BMT, 1 syngeneic BMT, 1 autologous BMT and 2 normal individuals. IFN-gamma mRNA expression increased after Con A stimulation in 6 patients who had limited chronic graft versus host disease (GVHD), 14 patients who did not have chronic GVHD, each one patient receiving syngeneic and autologous BMT and 2 normal individuals. On the other hand, IFN-gamma mRNA expression was not increased by Con A stimulation in 4 patients who had extensive chronic GVHD. Also, the concentration of IFN-gamma in cultured medium in a patient with extensive chronic GVHD was not detectable. A similar low response of IL-2 and IL-5 mRNA expression to Con A was observed in these patients with extensive chronic GVHD. These findings indicate that the cytokine productive capacity of T cell (IFN-gamma and IL-2 could be produced by type 1 T helper (Th1) cells and IL-5 could be produced by type 2 T helper (Th2) cells) was suppressed in patients who had extensive chronic GVHD, while that capacity was almost normal in patients without chronic GVHD and with limited chronic GVHD. Therefore, the analysis of cytokine gene response to Con A stimulation may provide useful information regarding immune reconstitution after BMT.

Adolescent↗

Hyperacute graft-versus-host disease accompanied by increased serum interleukin-6 levels.

Hyperacute graft-versus-host disease (GVHD), which progresses severely and rapidly, was observed in three patients with acute leukemia transplanted with bone marrow cells from human leukocyte antigens (HLA)-identical and mixed leukocyte reactions (MLR)-negative siblings. Hyperacute GVHD developed in these patients within 7 days after bone marrow transplantation (BMT) and was rapidly aggravated inspite of cyclosporin A (CyA) and short-term methotrexate (MTX) prophylaxis and treatment with bolus methylprednisolone (mPSL). These patients showed markedly increased serum interleukin-6 (IL-6) levels after BMT, whereas other cytokines such as interferon gamma (IFN gamma), tumor necrosis factor alpha (TNF alpha), and IL-2 were not increased compared with pretreatment levels. These findings suggest that markedly increased IL-6 levels may be related to hyperacute GVHD.

Acute Disease↗

Serum cytokine levels in bone marrow transplantation: synergistic interaction of interleukin-6, interferon-gamma, and tumor necrosis factor-alpha in graft-versus-host disease.

In patients with acute graft-versus-host disease (GVHD), IL-6 gradually increased > 14 days before clinical onset of acute GVHD and decreased when acute GVHD disappeared. Interferon-gamma (IFN gamma) levels increased < 14 days before clinical acute GVHD and decreased at the disappearance of acute GVHD. Tumor necrosis factor-alpha (TNF alpha) levels increased almost simultaneously with the onset of acute GVHD and also decreased when it disappeared. However, these results do not necessarily mean that the increased levels of IL-6, IFN gamma and TNF alpha induced acute GVHD; they merely show that acute GVHD is observed more frequently in patients with increased IL-6, IFN gamma and TNF alpha levels than in those with normal levels. Although increased IL-6 levels were also observed in patients without acute GVHD, concomitant increase of IFN gamma and TNF alpha was not detected in such cases, showing that IL-6 can be increased by even graft-versus-host reaction (GVHR) which may not develop into clinical acute GVHD. Taken together, acute GVHD appeared to be induced by synergistic interaction of IL-6, IFN gamma and TNF alpha, consistent with a cytokine cascade. A similar interaction of IL-6 and TNF alpha was also observed in chronic GVHD. Although IFN gamma levels were slightly increased in chronic GVHD and sometimes aggravated the disease status, IL-6 and TNF alpha appeared to be more closely involved in the induction of chronic GVHD. In autologous BMT, increased cytokine levels were not observed unless IL-2 was administered.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

[Reoperative coronary revascularization without cardiopulmonary bypass].

We report a case of successful reoperation of coronary revascularization without cardiopulmonary bypass. The patient was a 62-year-old man, who had undergone coronary artery bypass grafting (CABG) to the LAD and CX with two saphenous vein grafts (SVG) for the left main lesion 12 years before. He required reoperation for unstable angina due to progressive ischemic heart disease and the diseased SVG. Preoperative coronary angiogram revealed total occlusion of major 3 branches and the diseased SVG to the LAD. The reoperation was performed without cardiopulmonary bypass through the repeated median sternotomy for revascularization of the LAD and RCA. The left internal thoracic artery and the gastroepiploic artery were anastomosed to the LAD and RCA under the beating heart without any hemodynamic or electrocardiographic deteriorations. The operation was uneventfully finished in 3 hr 40 min. without the use of blood products. Postoperative angiogram showed both new grafts were widely patent, and he was discharged 14 days after the operation without angina. We also performed 4 other cases of reoperative CABG without cardiopulmonary bypass, and conclude that this technique is a safe and effective alternative in a carefully selected group of patients for reoperative CABG to reduce several technical problems related to coronary reoperation.

Abdominal Muscles↗

15-Deoxyspergualin controls cyclosporin- and steroid-resistant intestinal acute graft-versus-host disease after allogeneic bone marrow transplantation.

We report a case of cyclosporin- and methylprednisolone-resistant intestinal acute graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation which responded to a new immunosuppressant, 15-deoxyspergualin (DSG). Endoscopy showed lymphoid hyperplasia with CD3+, CD4+, CD8- lymphocyte infiltration into the submucosa of the jejunum and colon. DSG effectively suppressed this intestinal acute GVHD.

Acute Disease↗

Localization and characterization of gelsolin in nervous tissues: gelsolin is specifically enriched in myelin-forming cells.

Gelsolin is a Ca(2+)-sensitive actin filament-severing protein. To elucidate the role of gelsolin in nervous tissues, we have investigated localization and expression of gelsolin in rat CNS and PNS using biochemical and morphological methods with a polyclonal antibody against the COOH-terminal fragment of plasma gelsolin. Immunohistochemical study showed that gelsolin was specifically enriched in oligodendrocytes and Schwann cells, and was also detected in myelin sheath, especially around the Ranvier's nodes. The immunohistochemical stainings using indirect immunofluorescence, avidin-biotin-peroxidase complex, and immunogold methods were carefully confirmed by immunoblotting against the tissue homogenates. The expressional changes of gelsolin in developing brain were investigated. The protein was detectable in newborn rat brain; however, it began to increase at 8-10 d after birth and reached maximal at 20-30 d when myelinogenesis actively occurred. After this period, the protein decreased gradually, although myelin basic protein was increasing until 6 months after birth. The immunostaining of gelsolin in Schwann cells was enhanced upon regeneration of injured sciatic nerves by freezing. Immunoelectron microscopy revealed that gelsolin was present not only in the cytoplasm but also in compact myelin. Following solubilization by detergents, gelsolin in the myelin fraction could be purified using anion exchange and blue Sepharose column chromatographies. The purified protein possessed a Ca(2+)-dependent severing activity against actin filaments similar to that of cytoplasmic and plasma gelsolin. These data strongly suggest that gelsolin in nervous tissues might be involved in lamellipodial movement to wrap axons of myelin-forming cells by modulating actin polymerization.

Animals↗

[Reversal of myelofibrosis is an important pre-transplant factor for bone marrow grafting--a successful case of allogeneic bone marrow transplantation for an acute megakaryoblastic leukemia].

We report a successful ereated case of acute megakaryoblastic leukemia (AMKL) with myelofibrosis (MF), which achieved a disease free condition, with disappearance of MF, for over 24 months after allogeneic bone marrow transplantation (BMT) and summarized cases of MF receiving BMT reported in Japan to evaluate the influence of MF on engraftment of bone marrow (BM). A 40-year-old man was admitted on Jan. 29, 1991 due to anemia and thrombocytopenia. BM aspiration resulted in a dry tap and MF and cells stained positive with anti-GPIIb/IIIa (CD41a) antibody were demonstrated by BM the biopsy specimen. Complete remission was achieved by multi-drug chemotherapy including behenoylcytosine arabinoside, etoposide, mitoxantrone and prednisolone (PLS). After preconditioning with little BU+CY, BMT was performed from an HLA-identical brother on Jan. 16, 1992. From day 9 of post BMT, acute skin graft versus host disease (grade 1) was observed, which was controlled by 60 mg/day of PSL. Engraftment was achieved on day 12. Although cystitis developed, he was discharged on Apr. 5, 1992 and remains disease free. Including the present case, seven allogeneic BMT patient with MF have been reported so far in Japan. Four cases in whom MF recovered before BMT showed better results than other three cases that still showed MF at BMT. Reversal of MF seems to be a favorable pre-transplant factor for successful BMT in patients with MF.

Adult↗

[Clinical application of gene technology to monitor bone marrow transplantation].

We assessed the origin of peripheral blood cells and bone marrow cells obtained from 15 patients after allogeneic bone marrow transplantation (allo BMT) by sensitive two-step polymerase chain reaction (PCR) amplification of MCT118, a variable number of tandem repeats regions (VNTR), that can be used to detect the DNA pattern of a minor cell population of only 1% without using radioisotopes. Mixed chimerism(MC) was detected in the haematopoietic cells of 3 patients. Two patients developed relapse of leukaemia after the detection of MC and one patient died of bone marrow hypoplasia 7 months after BMT. These findings indicate the clinical usefulness of this method to monitor patients with MC. Also, we analyzed cytokine gene expression in peripheral blood mononuclear cells during the development of graft-versus-host disease (GVHD) in patients who underwent allo BMT using a semiquantitative reverse-transcriptase polymerase chain reaction (RT-PCR). The expression of interleukin(IL)-1 beta, IL-6, and tumor necrosis factor (TNF)-alpha mRNA was increased during the development of GVHD and the degree of this increment depended on the severity of the disease. These findings suggest that IL-1 beta, IL-6, and TNF-alpha produced by peripheral blood mononuclear cells play an important role in the development of GVHD. Therefore, analysis of MC and cytokine mRNA expression using the PCR technique after allogeneic bone marrow transplantation provide important information for treatment and monitoring of marrow transplant patients.

Adolescent↗

[Prognostic significance of DNA ploidy pattern on bile duct cancer].

Of 33 patients surgically treated for bile duct cancer, nuclear DNA content of cancer cells was assessed by flow cytometry in order to determine whether DNA ploidy pattern was a prognostic indicator. Thirteen patients (40%) had diploid tumors and 20 patients (60%) had aneuploid tumors including 12 patients with DNA heterogeneity. No significant correlation was found between DNA ploidy pattern and clinicopathological features. Survival of patients with diploid tumor was significantly longer than those with aneuploid tumor (p < 0.01). In aneuploid cases, the prognosis of patients with DNA heterogeneity was similar to those without DNA heterogeneity. In the patients who underwent a curative resection, 5-year survival rate of diploid cases was 100%, as opposed that no patients with aneuploid tumor survived longer than 4 years. These results suggest that DNA ploidy pattern is a important prognostic determinant for bile duct cancer.

Adult↗