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Biomedical subjects

Y Matsui

Publications and source records attributed to Y Matsui.

At least 649 records · Page 36Linked to original sources
PubMedDate not supplied

Thrombectomy of portal vein thrombosis in living donor liver transplantation.

We describe a case of living donor liver transplantation where an intrahepatic portal vein embolism was detected by intraoperative ultrasonography after the completion of portal and arterial anastomoses. The recipient portal vein trunk was clamped and the ligature of the graft's right portal branch was released, thus maintaining the sole arterial supply. Backward flushing of the portal system was achieved, which removed the clot through the reopened right portal branch without the need for thrombectomy by Fogarty balloon catheter.

Catheterization↗
PubMedDate not supplied

Hepatofugal portal flow due to acute cellular rejection.

We describe a case of living donor liver transplantation with hepatofugal portal flow caused by acute cellular rejection. The reversed portal flow was corrected by splenectomy and ligation of the residual collateral veins. Hepatofugal flow causes ischemic damage to the graft, which does not normalize spontaneously. In this particular case, meticulous Doppler ultrasound examination and prompt response to reversed portal flow salvaged the graft.

Adult↗
PubMedDate not supplied

Multicenter clinical trial for evaluating methylprednisolone pulse treatment of idiopathic optic neuritis in Japan. Optic Neuritis Treatment Trial Multicenter Cooperative Research Group (ONMRG).

BACKGROUND: A randomized, controlled clinical trial was conducted in 1991 to compare an intravenous megadose of methylprednisolone with a control drug (mecobalamin) for treating acute idiopathic optic neuritis. CASES: Sixty-six cases from 22 clinical centers throughout Japan were examined to evaluate the treatment on visual function parameters, such as visual acuity, visual field, color vision, contrast sensitivity, and critical flicker frequency. OBSERVATIONS: The methylprednisolone pulse treatment group showed faster recovery of visual function, particularly the visual acuity at 1 week (P<.05), Humphrey field analyzer mean deviation at 3 weeks (P<.05), and color vision at 1 week (P<.05). Recovery of contrast sensitivity at several different spatial frequencies was significant in the pulse treatment group at 1 (P<.01), 2 (P<.05), and 4 weeks (P<.05) after the start of treatment. Visual function test results at 12 weeks and 1 year were essentially the same in the two treatment groups. Side effects appeared more frequently in the pulse treatment group than in the control (P<.05). CONCLUSIONS: Pulse treatment does not appear effective for idiopathic optic neuritis even though visual function in the pulse treatment group of this trial recovered more quickly during the initial phase compared to the controls. More effective and specific treatment should be established for optic neuritis.

Adolescent↗
PubMedDate not supplied

Baseline features of idiopathic optic neuritis as determined by a multicenter treatment trial in Japan. Optic Neuritis Treatment Trial Multicenter Cooperative Research Group (ONMRG).

BACKGROUND: An optic neuritis treatment trial was conducted at 30 clinical centers in Japan using the same protocol. Patient participation was based on: age range of 14-55 years; acute symptoms indicative of unilateral optic neuritis of unknown or demyelinating origin; visual symptoms of 14-day duration or less; relative afferent pupillary defect in affected eye; and normal or swollen optic disc of affected eye. CASES: Initially, 102 patients qualified for participation; baseline data were obtained for analysis from 70 of these patients. Demographic characteristics of Japanese patients with optic neuritis were clarified and compared with those in a US study. OBSERVATIONS: The incidence of ocular or periocular pain and the presence of periventricular plaques were noted to be lower, and the incidence of disc swelling higher, in the Japanese patients, suggesting racial differences in the characteristics of the disease. Such differences may possibly be related to the lower incidence of multiple sclerosis in Japanese patients. The results of visual function tests were virtually the same in both studies. The nonaffected eyes of more than half the patients showed abnormal mean deviation in Humphrey field analysis, as also noted in the US study. CONCLUSIONS: The baseline clinical features of optic neuritis in the Japanese patients have been defined. Some racial differences in the characteristics of the disease may exist.

Adolescent↗
PubMedDate not supplied

Intragastric administration of ursodeoxycholic acid suppresses immunoglobulin secretion by lymphocytes from liver, but not from peripheral blood, spleen or Peyer's patches in mice.

Ursodeoxycholic acid (UDCA) has been recognized as a therapeutic drug for primary biliary cirrhosis (PBC) and chronic viral hepatitis. As one of the mechanisms by which UDCA improves liver function tests in those patients, its immunomodulatory effect is currently considered important. Although the suppressive effects of UDCA on some cytokine productions, T-cell mediated cytotoxicity and immunoglobulin production were observed from in vitro studies, the immunomodulation in vivo by UDCA remains unclear. In the present study, we investigated the effect of UDCA administration on the number of immunoglobulin secreting cells in liver, peripheral blood, spleen and Peyer's patches in mice using the enzyme linked immunospot assay and assessed whether the UDCA-mediated immunomodulation is liver-specific. It was demonstrated that intragastric administration of UDCA reduced immunoglobulin secretion by lymphocytes from liver, but not from peripheral blood, spleen, or Peyer's patches. However, immunoglobulin production of those lymphocytes cultured in the presence of UDCA was suppressed, irrespective of their distribution sites, in a UDCA dose-dependent manner. When the concentrations of UDCA in portal and peripheral blood were measured using high performance liquid chromatography, UDCA was detectable in the portal blood in UDCA-treated mice, but not in peripheral blood, suggesting that the concentrations of UDCA in the environment surrounding lymphocytes may be an important factor for the modulation of lymphocyte functions.

Adjuvants, Immunologic↗
PubMedDate not supplied

Soft-tissue osteochondroma in the calcaneal pad: a case report.

Soft-tissue osteochondromas of the foot are infrequently occurring lesions. A 65-year-old woman presented with soft-tissue osteochondroma in the soft tissues superficial to the plantar aspect of the calcaneus. The mass was densely ossified without cortical destruction or other alteration in the adjacent calcaneal bone on x-rays and computed tomography images. A 99m Tc bone scan showed a focal area of an increased uptake at the site of the mass below the calcaneus. Magnetic resonance imaging demonstrated high signal mass on T1-weighted images, isointense to fatty marrow, adjacent to the thickened plantar aponeurosis. The mass was completely excised. Histologically, mature lamellar bone was seen centrally, and the periphery was capped with hyaline cartilage. Since the tumor was located in the plantar aponeurosis and comprised of a single nodule of well-developed bone with well-organized endochondral ossification, the pathogenesis of this lesion might be related to metaplasia.

Aged↗
PubMedDate not supplied

Effects of frequent and sustained plateletapheresis on peripheral blood mononuclear cell populations and lymphocyte functions of normal volunteer donors.

Per procedure, plateletapheresis may remove 2 X 10(9) to 3 X 10(9) white cells from the peripheral blood of a normal donor. To investigate the effects of frequent and sustained plateletapheresis, multiple peripheral blood tests were performed on 25 volunteer donors undergoing plateletapheresis an average of 72 times over periods of up to 8 years, and results were compared with 25 age- and sex-matched controls who had not undergone apheresis. In donors, significant decreases were observed in: 1) both absolute number and percentage of T4+ cells; 2) absolute number of both T8+ cells and Leu-7+ cells; 3) T4/T8 ratio; 4) responses to both pokeweed mitogen and alloantigens; and 5) IgG levels. Significant increases were observed in percentages of both B cells and monocytes, and responses to both phytohemagglutinin and Concanavalin A. Plateletapheresis removes a large number of T4 and T8 cells, a moderate number of B cells, and a smaller number of monocytes and Leu-7 cells. The results suggest that during vigorous plateletapheresis the replenishment to peripheral blood per month was less than 1.83 X 10(9) and 0.93 X 10(9) for T4 cells and T8 cells, respectively, greater than 0.27 X 10(9) and 0.62 X 10(9) for B cells and monocytes, respectively, and approximately 0.39 X 10(9) for Leu-7 cells. Although no clinical effect was noted, these data suggest that frequent and sustained non-lymphocyte sparing plateletapheresis is associated with changes in laboratory findings related to the immune system.

Adolescent↗
PubMedDate not supplied

Near infrared spectrophotometry reflects cerebral metabolism during hypothermic circulatory arrest in adults.

Near-infrared spectrophotometry (NIRS) is assumed to reflect cerebral oxygenation during hypothermic circulatory arrest (HCA). However, the rationale for the use of NIRS as a marker of cerebral metabolism remains to be elucidated. We examined whether cerebral oxygenation measured by NIRS correlated with cerebral metabolic function assessed by cerebral oxygen extraction ratio (OER) during HCA in adults. NIRS was continuously monitored in 14 patients undergoing thoracic aortic surgery using HCA (17.9 +/- 2.9 degrees C esophageal temperature at HCA onset). Jugular venous oxygen saturation and OER were also monitored. OER was significantly reduced from 37.3 +/- 7.2% at the onset of cardiopulmonary bypass to 13.6 +/- 6.2% at the onset of HCA (p < 0.0001). A linear decrease in oxygenated-hemoglobin (oxy-Hb) and increase in deoxygenated-hemoglobin (deoxy-Hb) were found during HCA, which returned to baseline levels after rewarming. The rate of decrease in oxy-Hb and increase in deoxy-Hb were -0.63 +/- 0.45 and 0.51 +/- 0.30 (10(-5) OD/cm per sec), respectively, both of which significantly correlated with OER at the onset of HCA (R2=0.739 and 0.633; p < 0.0001 and p = 0.0007, respectively). NIRS may serve as a reliable diagnostic modality for monitoring cerebral metabolism during aortic surgery using HCA.

Adult↗
PubMedDate not supplied

Effect of hepatocyte volume on energy status in the cirrhotic rat liver.

To evaluate the effect of reduced hepatocyte volume on liver energy status, the relationship between the morphologically quantified hepatocyte volume and biochemical parameters, and the difference in nuclear density between the parenchyma and stroma were assessed in rat livers with thioacetamide-induced cirrhosis. The ratio of hepatocytes to whole liver tissue, defined as the 'hepatocyte area ratio', and the nuclear densities of the parenchyma and stroma were calculated microscopically with an image analysing system. Adenine nucleotide, protein and DNA contents, and the ornithine carbamoyltransferase activity in the liver were assayed. In the cirrhotic group, adenine nucleotide content, protein content and ornithine carbamoyltransferase activity were positively correlated with the hepatocyte area ratio, whereas DNA content was negatively correlated with this ratio. The adenylate energy charge of the cirrhotic liver was maintained at a constant level regardless of the ratio. Adenine nucleotide content, protein content and ornithine carbamoyltransferase activity per fractional 'hepatocyte area ratio' in cirrhotic livers were significantly lower than in control livers. The nuclear density of the stroma was significantly greater than that of the parenchyma. These results suggest that the lowered energy status in the cirrhotic liver is not caused by reduced hepatocyte volume but rather by impaired hepatocyte metabolism. In addition, the morphological measurement with an image analysing system was found to be useful for evaluating the effects of decreased hepatocyte volume on biochemical derangements in cirrhotic tissue.

Adenine Nucleotides↗
PubMedDate not supplied

Pathological studies on sarcoidosis autopsy. I. Epidemiological features of 320 cases in Japan.

Three hundred and twenty autopsy cases of sarcoidosis during a 32 year period were collected from the Annuals of the Pathological Autopsy Cases in Japan, published yearly since 1958, and from a literature survey. A statistical analysis of these reviewed autopsy cases was carried out on the epidemiological features of the disease and on the causes of death. The proportion of sarcoidosis autopsy cases relative to the total autopsy cases had increased during this 32 year period. The increase of sarcoidosis autopsies during this period was chiefly due to the increase in aged females; the total number of female cases was approximately two times more than that of males. As over half of the total cases had only a pathological diagnosis and not a clinical diagnosis for sarcoidosis, the actual morbidity from sarcoidosis that was estimated from the autopsy data and corrected by autopsy rate was over five times higher than that of the clinically recognized cases. Age and sex distribution of these cases peaked in the thirties for both sexes, while another very high peak was noted in females over 50 years of age. In approximately 60% of the sarcoidosis autopsies, the cause of death related to sarcoid lesions in the heart, lung or nervous system, the majority of which involved cardiac sarcoidosis. In the remaining 40% of the cases, the cause of death was from non-sarcoidosis diseases.

Adult↗
PubMedDate not supplied

Pathological studies on sarcoidosis autopsy. II. Early change, mode of progression and death pattern.

Three hundred and twenty autopsy cases of sarcoidosis in Japan were analyzed to determine the pathological changes in the early stage, the mode of progression in each organ and the changes in the final stage of the disease. The lung and the mediastinal lymph nodes were affected in most of the cases, while the lesions were limited to the lung and intrathoracic nodes in some of the cases. It was suspected that early changes developed in the lung and in the hilar, and then in the mediastinal lymph nodes. The progression of sarcoid granulomas in the lung was classified into three patterns: (i) probably of a disseminated hematogenous nature; (ii) of an interstitial lymphogenous nature; and (iii) of a local expansive nature. These three patterns were observed also in the heart. In the brain, perivascular granuloma formation was a prominent feature. In the other organs in which sarcoid lesions were not malignant nor disseminated and conglomerated, no interstitial patterns were observed. In chronic cases, repeated dissemination and particularly the interstitial spread of granulomatous changes led to a prominent interstitial fibrosis and dysfunction of the organs, finally resulting in death of the individual. In such long-standing cases, the mediastinal nodes deteriorated by hyalinous degeneration of the granulomas, and many active granulomas were formed in the intra-abdominal or body surface lymph nodes. These lymph nodes were likely to continue supplying sensitized lymphocytes to the whole body. A persistence of active change in the lymph nodes and the lymphogenous spread of granulomas in organs would appear to be key factors in the prognosis of sarcoidosis.

Adult↗