Biomedical subjects

K Oku

Publications and source records attributed to K Oku.

At least 19 recordsLinked to original sources

PubMed2003

Cerebral imaging by magnetic resonance imaging and single photon emission computed tomography in systemic lupus erythematosus with central nervous system involvement.

OBJECTIVE: To assess the significance of magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT) abnormalities in patients with systemic lupus erythematosus (SLE). METHODS: Forty-four patients with SLE were retrospectively analysed. Patients were classified into three groups [1 and 2: patients with central nervous system (CNS) manifestations before and after starting high-dose steroid therapy, respectively; 3: patients without CNS manifestations. MRI was performed in all 44 patients and SPECT in 31. RESULTS: Abnormal findings in MRI were found in 19 patients. MRI abnormalities were significantly more frequent in patients with CNS manifestations than in those without [71 vs 17%, odds ratio (OR) 11.9, confidence interval (CI) 2.8-49.9, P=0.0003]. After the initiation of steroid therapy, patients with CNS manifestations also had an increased frequency of abnormal MRI. No correlation was found between SPECT findings and CNS manifestations. However, patients with CNS manifestations after starting steroids showed a markedly increased frequency of abnormal MRI and SPECT compared with those without CNS manifestations (80 vs 7%; OR 56, CI 4.4-719, P=0.0003). The positive predictive value of abnormality in both techniques in developing CNS manifestations after starting steroids was 89%. CONCLUSION: MRI findings correlated with CNS manifestations in SLE. Where there is a high suspicion of CNS involvement, the combination of MRI and SPECT may be useful in predicting CNS manifestations after starting steroid therapy.

Adolescent↗

PubMed2002

Development of liver dysfunction after delivery is possibly due to postpartum autoimmune hepatitis. A report of three cases.

Autoimmune diseases, especially autoimmune thyroid disease, frequently develop after delivery due to the immune rebound mechanism. Most cases involve transient dysfunction of affected organs. We examined three patients who developed liver dysfunction after delivery. They were all diagnosed with definite or probable autoimmune hepatitis using the scoring system of the International Autoimmune Hepatitis Group. Moreover, all of them had anti-CYP2D6 antibodies detected by a sensitive radioligand assay. Our findings strongly suggest that liver dysfunction is induced by postpartum autoimmune hepatitis, and clinicians should be aware of this disease.

Adult↗

PubMed2001

Microscopic polyangiitis complicated with massive intestinal bleeding.

Microscopic polyangiitis (MPA) is associated with renal dysfunction, in most cases, and occasionally with pulmonary hemorrhage. However, massive intestinal bleeding is a rare manifestation. We report a case of MPA in a man who developed arterial bleeding in the small intestine. A 74-year-old man was admitted after enduring a fever for 4 weeks. Laboratory examination revealed leucocytosis with neutrophil predominance, and renal dysfunction was noted. He did not respond to treatment with antibiotics, and the worsened renal function soon required hemodialysis. On the seventh hospital day, he suddenly developed massive melena. A colonoscopic examination suggested bleeding in the small intestine, and abdominal angiography demonstrated that the bleeding originated in a branch of the ileal artery. Hemostasis was achieved by transarterial embolization (TAE), but the patient suffered a massive pulmonary hemorrhage 2 days after the TAE. Although he responded well to a combination treatment with corticosteroid and cyclophosphamide, recurrence of pulmonary hemorrhage led to death, on the 87th hospital day. MPA in this patient was associated with three serious complications; deteriorating renal function, massive melena, and pulmonary hemorrhage. Of the various manifestations associated with MPA, arterial bleeding in the gastrointestinal tract, although rare, should be considered as one of the serious complications in MPA.

Aged↗

PubMed2001

Time-related changes of the cardiovascular system during maintenance anesthesia with sevoflurane and isoflurane in horses.

To clarify time-related changes in equine cardiovascular system during maintenance anesthesia (180 min, 1.2 minimum alveolar concentration) with sevoflurane (Sev-group) compared to isoflurane (Iso-group) as the basis for clinical use of Sev, horses were examined for the heart rate (HR), mean arterial pressure (MAP), cardiac index (CI), systemic vascular resistance (SVR) and pre-ejection period (PEP)/ejection time (ET) that is an index of the cardiac contractility. The HR was almost 30 beats/min in both groups without significant temporal change. MAP was significantly elevated with time but there was no significant difference between the groups. In the Sev-group, CI remained unchanged but the significant increase of CI with time was observed in the Iso-group. In the Sev-group SVR was significantly higher than that of the Iso-group and increased with time. No significant difference of PEP/ET was seen between the groups, but PEP/ET lowered with time in the Iso-group in association with prolonged ET. The results indicated that the time-dependent elevation of MAP in the Sev-group reflected increased SVR without increase of CI and that it reflected increased CI resulting from increased stroke volume in the Iso-group in association with lowered PEP/ET, that is, increased cardiac contractility.

Anesthesia, Inhalation↗

PubMed2000

Anesthetic management with sevoflurane and oxygen for orthopedic surgeries in racehorses.

Eighty-five thoroughbred racehorses with various types of fracture were subjected to arthroscopic surgery (44 horses) or internal fixation (41 horses) under sevoflurane anesthesia. The mean end-tidal sevoflurane concentration during anesthesia ranged from 2.5 to 2.8%. PaCO2 was maintained between 50 and 65 mmHg by controlled ventilation. The mean arterial blood pressure was maintained above 65 mmHg by infusion of dobutamine and fluids, however, heart rate significantly increased with time. Recovery from anesthesia was calm and smooth in almost all cases. No apparent complication was observed during and after anesthesia in all cases. Therefore, sevoflurane anesthesia is considered to be safe and useful for orthopedic surgery in racehorses.

Anesthetics, Inhalation↗

PubMed1999

Changes of neurotransmitters in the brainstem of patients with respiratory-pattern disorders during childhood.

We examined neuropathologically and immunohistochemically the respiratory centers in the brainstem of two patients with Joubert syndrome (JS), three patients with congenital central hypoventilation syndrome (CCHS) and a patient with apneustic breathing (prolonged inspiratory pause) due to unknown etiology. Immunoreactivity (IR) of tryptophan hydroxylase (TPH) was decreased in the dorsal raphe nuclei of two patients with JS compared with age-matched controls, as well as in two patients with Dandy-Walker malformation. The two JS patients showed vermian defect and elongated cerebellar peduncles, and peculiar vascularities in the midline of the whole brainstem were also noted in one of these patients. These findings, as a whole, confirm that the midline structures of brainstem are disordered both structurally and functionally in JS, conceivably resulting in respiratory patterns and psychomotor deficits. IR of serotonin 1A receptor showed no significant changes in the medulla oblongata of these patients, however. In the parabrachial complex, IR of substance P was increased in two patients with CCHS, and one with apneustic breathing. IR of tyrosine hydroxylase was also increased in the latter. The brainstem of these patients showed reactive astrogliosis. These findings suggest preceding hypoxic episodes as well as an increased activity in the parabrachial complex which plays an important role in conducting the driving force to the medullary respiratory neurons from ascending sensory pathways.

Brain Stem↗

PubMed1997

Effects of glycyrrhizin on immune-mediated cytotoxicity.

Intravenous administration of glycyrrhizin is known to decrease elevated plasma transaminase levels in patients with chronic viral hepatitis, in which immune-mediated cytotoxicity by cytotoxic T lymphocytes and tumour necrosis factor (TNF)-alpha is considered to play an important pathogenic role. However, the immunological interpretation of the transaminase-lowering action of glycyrrhizin is not known. Studies were performed to elucidate this action immunologically by assessing the effects of glycyrrhizin on immune-mediated cytotoxicity using an antigen-specific murine CD4+ T hybridoma line, which exhibits cytotoxicity against antigen-presenting cells after stimulation with specific antigen, and a murine TNF-alpha-sensitive fibroblast line. Glycyrrhizin inhibited the cytotoxic activity of the T cells against antigen-presenting cells and also suppressed TNF-alpha-induced cytotoxicity in the TNF-alpha-sensitive cell line in vitro. These results suggest that the decrease of elevated transaminase levels by glycyrrhizin in patients with chronic viral hepatitis is mediated in part by inhibition of immune-mediated cytotoxicity against hepatocytes.

Animals↗

PubMed1997

Relation of urinary sodium excretion to blood pressure, glucose metabolism, and lipid metabolism in residents of an area of Japan with high sodium intake.

To evaluate the effects of prolonged intake of a high-sodium diet on glucose and lipid metabolism, we examined the relation of daily urinary sodium excretion to blood pressure, glucose metabolism, and lipid metabolism in 140 Japanese adults who lived in a region where the average daily consumption of sodium was high and stable during the past 15 yr; no subject had received any treatment for hypertension or metabolic disorders. Each subject was admitted to our health examination center for 2 d for measurement of blood pressure, sampling of blood, and glucose tolerance testing. A 24-h urine specimen was collected by each subject after discharge. Multiple regression analysis revealed that urinary sodium excretion was significantly independent of the mean blood pressure and was unrelated to the area under the serum glucose curve after glucose administration. The urinary sodium level was also unrelated to low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol. The prevalence of hypertension in the group with a daily sodium excretion below 140 mEq (low sodium group) was 0%, while that in the group with a daily sodium excretion above 280 mEq (high sodium group) was 44%; this difference was significant (p < 0.01). No significant difference was observed in the prevalence of metabolic disorders between the two groups. Our results suggest that sodium intake has little influence on glucose and lipid metabolism but has a significant influence on blood pressure in normotensive and untreated hypertensive subjects who reside in an area with a relatively high sodium intake.

Adult↗

PubMed1997

Calculation of mitral valve area in mitral stenosis using the proximal isovelocity surface area method. Comparison with two-dimensional planimetry and Doppler pressure half time method.

Two-dimensional echocardiographic (2-D) planimetry and the Doppler pressure half-time (PHT) method have been used to estimate mitral valve area (MVA) in patients with mitral stenosis (MS). Recently, the proximal isovelocity surface area (PISA) method has been shown to be accurate for calculating MVA. The purpose of this study was to compare the PISA method with previous methods. Thirty patients with MS were studied; 17 had pure MS, 4 combined mild MR, 6 combined mild AR, and 3 combined MR and AR. Color Doppler flow mapping was performed at an aliasing (blue-red interface) velocity of 14 cm/sec using the zero-baseline shift. MVA was calculated as 2 x 3.14 x R2 x 14 x (theta/180) / PFV, where R is the distance from aliasing to orifice, 14 is the aliasing velocity, theta is the internal angle of the mitral valve, and PFV is the peak flow velocity at the mitral orifice. MVA was also calculated using the 2-D and PHT methods, and compared with the PISA method. MVA calculated using the PISA method correlated well with the 2-D (r=0.90, p < 0.01, SEE = 0.18 cm2) and PHT methods (r=0.82, p < 0.01, SEE = 0.24 cm2). Compared with the 2-D method, the standard error of the estimate of the PISA method was - 0.14+/-0.18 cm2 and the percent error was -10.4+/-18.9%. Compared with the PHT method, the standard error of the estimate of the PISA method was + 0.01+/-0.24 cm2 and the percent error was +3.4+/-34.6%. MVA calculated using the PISA method correlated well with the 2-D and PHT methods in patients with pure MS or with MS combined mild regurgitation. The PISA method may be useful for calculating MVA as an alternative method.

Adult↗

PubMed1996

Effect of 4G-beta-D-galactosylsucrose (lactosucrose) on fecal microflora in patients with chronic inflammatory bowel disease.

Metabolic interaction between the intestinal microflora and the host has been suggested to play a role in the pathogenesis of chronic inflammatory bowel disease. Elemental or low-fat, low-residual diets in patients with Crohn's disease or ulcerative colitis are reported to decrease anaerobic bacteria and to change the composition of the intestinal microflora. We examined the effect of an indigestible agent, 4G-beta-D-galactosylsucrose (lactosucrose), which is selectively utilized by intestinal Bifidobacterium, on the composition of the intestinal microflora. After the administration of lactosucrose to two patients with Crohn's disease and five patients with ulcerative colitis for 2 weeks, significant induction of the growth of Bifidobacterium was observed, and significant reduction in the population level of Bacteroidaceae was seen. Bowel movements improved in four patients. The intestinal environment, estimated by measuring fecal pH, fecal levels of short-chain fatty acids and putrid products, and the urinary secretion of indican, also improved in these patients. These results suggest that lactosucrose may be useful for patients with chronic inflammatory bowel disease.

Adolescent↗

PubMed1996

Partial deletion of the long arm of chromosome 11: ten Japanese children.

The clinical features of partial deletion 11q were correlated with the size of the deleted region. Ten Japanese children with partial deletion of 11q were investigated. They were divided into three groups. Three patients in the first group had interstitial deletions and preserved subband q24.1. Six patients in the second group demonstrated terminal deletion of 11q including subband q24.1, with typical features of 11q- syndrome (Jacobsen syndrome). The third group included only one patient, who had terminal deletion of 11q without characteristics of typical 11q- syndrome. Prominent features of patients in the first group included severe mental and motor developmental delay, seizures, cleft lip and palate, and ophthalmological findings. Patients in the second group showed mild to moderate developmental delays without deterioration. Abnormalities in neuroimages, high intensity in the cerebral white matter in T2-weighted magnetic resonance (MR) images, and recurrent infections were not observed after the age of 7 years. The subject in the third group, with the smallest amount of deleted chromosome, did not show developmental delays, suggesting that some unknown genes related to developmental delays may be located adjacent to subband q24.1. Variation in the deleted parts of 11q resulted in different clinical features in each group.

Abnormalities, Multiple↗

PubMed1996

Evaluation of the coagulation and fibrinolytic systems in men with intermittent claudication.

The authors evaluated elements of the coagulation and fibrinolytic systems in 18 male patients with intermittent claudication vs 19 men matched for risk factors who served as controls. Prothrombin time and activated partial thromboplastin time did not significantly differ in the patients and the controls. The plasminogen level in the two groups was not significantly different. The level of lipoprotein(a) was significantly higher in the patients than in the controls. The levels of antigen and the activity of protein C did not differ significantly between the two groups. The thrombomodulin level was significantly higher in the patients than in the controls. There were no significant differences between the two groups in the levels of alpha 2-macroglobulin, C1-inactivator, or antithrombin III. The levels of fibrinogen and alpha 1-antitrypsin were significantly higher in the patients vs the controls. Significantly lower levels of alpha 2-plasmin inhibitor and higher levels of alpha 2-plasmin inhibitor/plasmin complex and thrombin/antithrombin III complex were found in the patients vs the controls. These findings suggest that the levels of thrombin/antithrombin III complex, alpha 2-plasmin inhibitor/plasmin complex, and thrombomodulin may perhaps serve as indicators for injury to the peripheral endothelium and that the coagulation and fibrinolytic systems may be activated in patients with intermittent claudication.

Aged↗

PubMed1996

Relation of C4b-binding protein to athero-sclerosis of the descending thoracic aorta.

C4b binding protein (C4bp) is a regulator of the classical pathway of the complementing system. It forms a complex with protein S which serves as a cofactor of coagulation inhibitor, protein C. We have reported that C4bp is an acute phase reactant and associated with total cholesterol and triglyceride concentrations (Biochim. Biophys. Acta 963 (1988) 98-108). This suggests a possible association of C4bp with athero-sclerosis. We examined the relation of C4bp levels and the severity of atherosclerosis of the descending thoracic aorta in 98 Japanese men. The severity of aortic atherosclerosis was assessed by average sclerotic length (ASL) and average sclerotic area (ASA), using transesophageal echocardiography. After adjustment for age, C4bp levels increased significantly with increasing ASL and ASA. The association remained significant even after adjusting for total cholesterol, hypertension, smoking, drinking, body mass index, fasting blood sugar, and uric acid. Immunohistochemical analysis of specimens of the descending thoracic aorta from autopsies, demonstrated the presence of C4bp in the foamy macrophages of fatty streaks and the necrotic core of atheromatous plaque. These findings indicate that the serum level of C4bp can serve as an independent indicator of aortic athero-sclerosis.

Adult↗

PubMed1995

Hirschsprung's disease associated with Ondine's curse: a special subgroup?

The authors report a case of the rare occurrence of congenital central hypoventilation syndrome (Ondine's curse) and long segmental colonic aganglionosis (Hirschsprung's disease). A review of 24 reported cases showed that the proportion of females having this concurrence is higher than for ordinary Hirschsprung's disease. It also appears that the aganglionic segment is much longer in these cases than in ordinary Hirschsprung's disease.

Female↗

PubMed1995

Relationship of cigarette smoking to the severity of coronary and thoracic aortic atherosclerosis.

We studied the relationship of cigarette smoking to the severity of coronary and thoracic aortic atherosclerosis in 116 men who received coronary angiography and transesophageal echocardiography. Severity of coronary atherosclerosis was assessed in terms of Gensini's score (GS), and that of thoracic aortic atherosclerosis was assessed by the average sclerotic length (ASL) and average sclerotic area (ASA). The plasma fibrinogen levels were significantly positively correlated with smoking, and fasting blood sugar levels tended to be positively associated with smoking. GS was inversely associated with serum levels of high density lipoprotein (HDL) cholesterol. ASL and ASA were positively associated with age, fasting blood sugar levels and plasma fibrinogen levels, and these associations were statistically significant. Analysis of covariance was used to examine the net association between cigarette smoking and GS, ASL or ASA controlling for age, total cholesterol, HDL cholesterol, fasting blood sugar and plasma fibrinogen. We found that GS, ASL, and ASA were all significantly increased with increasing number of cigarette years. Additional adjustment for other risk factors (triglyceride, uric acid, body mass index, alcohol use and hypertension) also showed a strong independent contribution of smoking to GS, ASL and ASA. We concluded that the cumulative exposure to cigarette smoking was an independent indicator of the severity of coronary atherosclerosis as well as thoracic aortic atherosclerosis.

Adult↗

PubMed1995

Evaluation of abnormal signal-averaged electrocardiograms in young athletes.

Our objectives in this study were to determine the incidence of abnormal signal-averaged ECG (SAECG) and its relation to the extent and type of exercise in young healthy athletes, and to evaluate the association, if any, between the development of abnormal SAECGs and vigorous exercise. The presence of abnormal SAECG was evaluated in 796 athletes (mean age 19 years), and its relation to findings on 12-lead electrocardiogram, echocardiogram, and the presence arrhythmias was studied using Holter monitoring. An SAECG was considered abnormal when any one of the three following criteria was met: filtered QRS duration of more than 114 msec, root-mean-square voltage in the terminal 40 msec of less than 20 muV, or a voltage of less than 40 muV for more than 38 msec. Abnormal SAECGs were present in 68 (8.5%) of the athletes and were associated with a smaller left ventricular mass. Athletes who performed anaerobic exercise tended to exhibit a high incidence of abnormal SAECGs, which was associated with a smaller left ventricular mass. No serious ventricular arrhythmias were observed on 24 h Holter monitoring or during the follow-up period of 20 +/- months. There were no sudden cardiac deaths. Continuous anaerobic exercise may induce abnormal SAECGs through the development of delayed myocardial conduction or electrical inhomogeneity in cardiac tissue. Te presence of an abnormal SAECG was unrelated to the development of arrhythmias in young athletes.

Adult↗

PubMed1995

[Involvement of substance P in gastric mucosal lesions of patients with rheumatoid arthritis].

We investigated the relation between gastric mucosal lesions and substance P (SP) in 64 patients with rheumatoid arthritis (RA) taking nonsteroidal antiinflammatory drugs (NSAIDs). In these patients, the incidence of gastric mucosal lesions was as high as 53.1%. Serum SP levels were significantly higher in patients with gastric mucosal lesions than in those without gastric lesions. Erythrocyte sedimentation rate, serum C-reactive protein and rheumatoid factor (RF) levels were also higher in patients with gastric mucosal lesions. A positive correlation between serum SP and RF levels was found in patients with RA. Experimental gastric mucosal lesions induced by an oral administration of indomethacin in rats were significantly enhanced by an additional intraperitoneal injection of SP. From these observations, it is suggested that, in addition to the effect of NSAIDs, SP elevation in blood has a role in the development of gastric mucosal lesion in patients with RA.

Animals↗

PubMed1995

[A case of rhinocerebral phycomycosis].

Rhinocerebral phycomycosis is an uncommon opportunistic infection with ubiquitous fungi of the class Phycomycetes, starting in the nose and extending to the paranasal sinuses and then intracranially. The condition is often characterized by poor prognosis because of occlusion of the internal carotid artery. This disease is commonly associated with predispositions such as uncontrolled diabetes mellitus, which is the most common, immunosuppressive states and metabolic bankruptcy including leukemia, lymphoma, myeloma, malnutrition, uremic or diarrheal acidosis, severe burns, anemia, carcinoma, radiotherapy, liver cirrhosis, hemochromatosis, tuberculosis, septicemia, long-term medication of steroid, antibiotics and antimetabolite, drug addiction, cytotoxic drug administration and AIDS. Cases with unknown predisposition, however, have been infrequently reported in the literature. The authors report a case of rhinocerebral phycomycosis in which concurrence of Candida species instead of the above-mentioned common predispositions was considered a potential predisposition. To our knowledge, only 1 report in which Candida species are referred to as a potential predisposition for this disease has been previously issued. A 85-year-old man was admitted to our hospital on March 2, 1994 because of generalized convulsion. He had received a total extirpation of an ascending colon cancer in July 1993. On admission, physical inspection showed no abnormalities and neurological examination revealed obtunded consciousness without other abnormalities. He had no diabetes mellitus. Hematological and blood chemistry values were normal except for CA19-9 of 45 U/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗