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Biomedical subjects

K Harada

Publications and source records attributed to K Harada.

At least 127 records · Page 7Linked to original sources
PubMed2001

Cardiorespiratory exercise capacity and its relation to a new Doppler index in children previously treated with anthracycline.

The purpose of this study was to assess the exercise capacity of patients treated with anthracycline and to evaluate the relation between the exercise capacity and a new Doppler index. The study patients consisted of 70 subjects: 41 healthy subjects and 29 who had been treated with various cumulative doses of anthracycline (range 45 to 873 mg per body surface area). The following conventional echocardiographic parameters were measured: rate-corrected mean velocity of fiber shortening (mVcfc), end-systolic wall stress (ESS), stress-velocity index, and early and late diastolic mitral inflow velocities and their ratio. A new Doppler index, the Tei index, was calculated as the sum of isovolumic contraction time and isovolumic relaxation time divided by the ejection time. Peak oxygen uptake (pVo(2)) and anaerobic threshold (AT) were measured during an upright bicycle exercise test. The pVo(2) and AT in the patient group were significantly lower than those in the control group (pVo(2): 22.0 +/- 3.7 versus 28.5 +/- 7.1 mL/min/kg; AT: 12.7 +/- 1.9 versus 17.3 +/- 4.3 mL/min/kg, respectively; P <.01). There were no significant differences in the mVcfc, ESS, stress-velocity index, E wave, A wave, or E/A wave ratio between the two groups. However, the mean Tei index of the patients was significantly greater than that of the controls (0.41 +/- 0.11 versus 0.33 +/- 0.04, P <.01). The pVo(2) and AT decreased significantly with an increase in the Tei index (r = -0.64 and -0.60, respectively; P <.01). A weak positive correlation was found between the AT and E/A wave ratio (r = 0.54, P <.05). However, no significant correlations were seen between the exercise parameters and the mVcfc, ESS, stress velocity index, or transmitral velocities. Our findings suggest that cardiopulmonary exercise testing revealed an inverse correlation between exercise capacity and the Tei index.

Adolescent↗
PubMed2001

Changes in bite force and occlusal contact area after orthognathic surgery for correction of mandibular prognathism.

OBJECTIVE: This study examined the long-term changes of bite force and occlusal contact area in patients with prognathous after orthognathic surgery with a newly developed pressure-sensitive sheet (Dental-Prescale; Fuji Photo Film Co). STUDY DESIGN: Fifty-seven patients with prognathous were examined. Bite force and occlusal contact area were measured just before operation and at 2 weeks, 1 month, 3 months, 6 months, 1 year, 2 years, and 3 years after operation. Forty control subjects with normal occlusion were also measured. RESULTS: The bite force and occlusal contact area of the patients were significantly greater than the preoperative level at 1 year, 2 years, and 3 years after operation. However, they were still significantly lower than the control subject level even at 3 years after operation. CONCLUSIONS: This study suggests that orthognathic surgery improves the bite force and occlusal contact area of patients with prognathous. However, at 3 years from the time of operation, patients had not reached control subject levels.

Adolescent↗
PubMed2001

Current efficacy of postexposure prophylaxis against measles with immunoglobulin.

We assessed results after postexposure prophylaxis against measles with immunoglobulin administered intramuscularly. Children were given 0.33 mL/kg of immunoglobulin from commercially available lots containing various titers of measles antibody within 5 days after exposure. In children receiving immunoglobulin with a titer of < or =16 IU/mL, 57% had clinically evident measles. Immunoglobulin preparations with higher measles antibody titers are required.

Female↗
PubMed2001

Intrahepatic cholangitis and arteritis after transcatheter arterial embolization in a patient with tumor-like lesion-associated autoimmune hepatitis.

Autoimmune hepatitis is a chronic liver disease characterized by immune-mediated, progressive hepatocellular damage, although the target autoantigen remains speculative. Intrahepatic biliary lesions are not a feature of this disease. We describe herein a female patient, 57 years, with autoimmune hepatitis who developed hepatic regenerative mass after acute exacerbation of hepatitis. This hepatic regenerative mass was clinically diagnosed as hepatocellular carcinoma and was surgically resected after transcatheter arterial embolization therapy. Widespread nonsuppurative destructive granulomatous cholangitis as well as necrotizing, granulomatous arteritis of the intrahepatic small arteries were found in the surgically resected hepatic regenerative mass. The bile duct lesions were histologically and immunohistochemically very similar to the granulomatous cholangitis of primary biliary cirrhosis. We would like to propose that these unusual lesions in the intrahepatic bile ducts and intrahepatic arteries represent a reaction of this patient to an anti-cancer drug included in chemoembolization. No such cases have been reported so far.

Arteritis↗
PubMed2001

Monitoring of the refolding process for immobilized firefly luciferase with a biosensor based on surface plasmon resonance.

In order to examine the possibility of the use of a surface plasmon resonance (SPR) sensor for real-time monitoring of the process of refolding of immobilized proteins, the refolding of firefly luciferase immobilized on a carboxymethyldextran matrix layer was analyzed. The SPR signal of the immobilized luciferase decreased after unfolding induced by GdnCl and increased gradually in the refolding buffer, while there was no signal change in the reference surface lacking the immobilized protein. The decrease in the SPR signal on unfolding was consistent with the difference between the refractive indices of the native and unfolded protein solutions. The effects of blocking of the excess NHS-groups of the matrix layer on the refolding yield were examined by means of an SPR sensor. The results were consistent with those obtained with the enzymatic activity assay, indicating that the changes in the SPR signal reflected the real-time conformational changes of the immobilized protein. Hence, an SPR biosensor might be used for monitoring of the process of refolding of immobilized proteins and as a novel tool for optimization of the refolding conditions. This is the first demonstration that SPR signal changes reflect the conformational changes of an immobilized protein upon unfolding and refolding.

Animals↗
PubMed2001

Hepatic sarcoidosis with vanishing bile duct syndrome, cirrhosis, and portal phlebosclerosis. Report of an autopsy case.

A few cases of sarcoidosis are associated with progressive liver disease, with a wide variety of clinicopathologic features. Herein, we report an autopsy case (65-year-old man). During an examination for liver dysfunction, cirrhosis with cholestatic dysfunction and splenomegaly were found. Needle liver biopsy revealed cirrhosis with lymphocytic piecemeal necrosis, dense septal fibrosis, and ductopenia. In addition, noncaseating epithelioid granuloma was also seen in the periportal region. Ductal enzymes and immunoglobulin M (IgM) levels were elevated, although antimitochondrial antibodies were negative. Instead, angiotensin-converting enzyme was elevated. He died of pulmonary failure and lung cancer. The autopsy liver (1,220 g) showed multinodular cirrhosis with broad and dense septa that divided the parenchyma. Mild lymphoid cell infiltration was seen in the periportal region. About a half of the interlobular bile ducts were lost, and the remaining bile ducts showed prominent periductal fibrosis, resembling sclerosing cholangitis. Interestingly, a few interlobular bile ducts showed chronic nonsuppurative cholangitis with epithelioid granulomas. Intrahepatic portal veins showed luminal narrowing with prominent phlebosclerosis. Hepatobiliary pathologies that resemble primary biliary cirrhosis and primary sclerosing cholangitis and that are followed by vanishing bile duct syndrome, chronic active hepatitis-related cirrhosis, and intrahepatic portal venous phlebosclerosis occur in a single case of sarcoidosis.

Bile Ducts, Intrahepatic↗
PubMed2001

Facial palsy associated with mumps parotitis.

Peripheral facial nerve paralysis is relatively common in the pediatric age group. However, facial palsy rarely has been documented in patients with mumps parotitis. This case report describes the findings of a 3-year-old Japanese boy who developed facial palsy immediately after mumps parotitis. This work calls attention to a possible association between mumps parotitis and facial palsy.

Child, Preschool↗
PubMed2001

Identification of liver X receptor-retinoid X receptor as an activator of the sterol regulatory element-binding protein 1c gene promoter.

In an attempt to identify transcription factors which activate sterol-regulatory element-binding protein 1c (SREBP-1c) transcription, we screened an expression cDNA library from adipose tissue of SREBP-1 knockout mice using a reporter gene containing the 2.6-kb mouse SREBP-1 gene promoter. We cloned and identified the oxysterol receptors liver X receptor (LXRalpha) and LXRbeta as strong activators of the mouse SREBP-1c promoter. In the transfection studies, expression of either LXRalpha or -beta activated the SREBP-1c promoter-luciferase gene in a dose-dependent manner. Deletion and mutation studies, as well as gel mobility shift assays, located an LXR response element complex consisting of two new LXR-binding motifs which showed high similarity to an LXR response element recently found in the ABC1 gene promoter, a reverse cholesterol transporter. Addition of an LXR ligand, 22(R)-hydroxycholesterol, increased the promoter activity. Coexpression of retinoid X receptor (RXR), a heterodimeric partner, and its ligand 9-cis-retinoic acid also synergistically activated the SREBP-1c promoter. In HepG2 cells, SREBP-1c mRNA and precursor protein levels were induced by treatment with 22(R)-hydroxycholesterol and 9-cis-retinoic acid, confirming that endogenous LXR-RXR activation can induce endogenous SREBP-1c expression. The activation of SREBP-1c by LXR is associated with a slight increase in nuclear SREBP-1c, resulting in activation of the gene for fatty acid synthase, one of its downstream genes, as measured by the luciferase assay. These data demonstrate that LXR-RXR can modify the expression of genes for lipogenic enzymes by regulating SREBP-1c expression, providing a novel link between fatty acid and cholesterol metabolism.

Alitretinoin↗
PubMed2001

Role of mitochondrial and sarcolemmal K(ATP) channels in ischemic preconditioning of the canine heart.

We tested whether mitochondrial or sarcolemmal ATP-sensitive K(+) (K(ATP)) channels play a key role in ischemic preconditioning (IP) in canine hearts. In open-chest beagle dogs, the left anterior descending artery was occluded four times for 5 min each with 5-min intervals of reperfusion (IP), occluded for 90 min, and reperfused for 6 h. IP as well as cromakalim and nicorandil (nonspecific K(ATP) channel openers) markedly limited infarct size (6.3 +/- 1.2, 8.9 +/- 1.9, and 7.2 +/- 1.6%, respectively) compared with the control group (40.9 +/- 4.1%). A selective mitochondrial K(ATP) channel blocker, 5-hydroxydecanoate, partially blunted the limitation of infarct size in the animals subjected to IP and those treated with cromakalim and nicorandil (21.6 +/- 3.8, 25.1 +/- 4.6, and 19.8 +/- 5.2%, respectively). A nonspecific K(ATP) channel blocker, glibenclamide, completely abolished the effect of IP (38.5 +/- 6.2%). Intracoronary or intravenous administration of a mitochondria-selective K(ATP) channel opener, diazoxide, at >100 micromol/l could only partially decrease infarct size (19.5 +/- 4.3 and 20.1 +/- 4.4%, respectively). In conclusion, mitochondrial and sarcolemmal K(ATP) channels independently play an important role in the limitation of infarct size by IP in the canine heart.

Adenosine Triphosphate↗
PubMed2001

Ataxic form of chronic inflammatory demyelinating polyradiculoneuropathy: clinical features and pathological study of the sural nerves.

We investigated clinical and pathological features of the sural nerves of 5 patients with the ataxic form of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and compared these features with those of chronic ataxic neuropathies due to other causes. The CIDP patients presented with slowly progressive ataxia with deep sensory impairment. The durations of the symptoms from onset were relatively short in CIDP (4-8 months) and cancer (3 and 10 months), but long in chronic idiopathic ataxic neuropathy (24-260 months). Corticosteroid therapy elicited a good response in all the patients with CIDP, but a poor response in the patients with other ataxic neuropathies. Sural nerve biopsy of CIDP patients showed a slight or moderate loss of myelinated fiber. This report suggests that ataxic form of CIDP is a steroid-responsive ataxic neuropathy, and large myelinated fibers of the sural nerves in ataxic form of CIDP were better preserved than those in nerves with other chronic ataxic neuropathies.

Adult↗
PubMed2001

Troglitazone inhibits atherosclerosis in apolipoprotein E-knockout mice: pleiotropic effects on CD36 expression and HDL.

Atherosclerotic coronary heart disease is a common complication of the insulin resistance syndrome that can occur with or without diabetes mellitus. Thiazolidinediones (TZDs), which are insulin-sensitizing antidiabetic agents, can modulate the development of atherosclerosis not only by changing the systemic metabolic conditions associated with insulin resistance but also by exerting direct effects on vascular wall cells that express peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a nuclear receptor for TZDs. Here we show that troglitazone, a TZD, significantly inhibited fatty streak lesion formation in apolipoprotein E-knockout mice fed a high-fat diet (en face aortic surface lesion areas were 6.9+/-2.5% vs 12.7+/-4.7%, P<0.05; cross-sectional lesion areas were 191 974+/-102 911 micrometer(2) vs 351 738+/-175 597 micrometer(2), P<0.05; n=10). Troglitazone attenuated hyperinsulinemic hyperglycemia and increased high density lipoprotein cholesterol levels. In the aorta, troglitazone markedly increased the mRNA levels of CD36, a scavenger receptor for oxidized low density lipoprotein, presumably by upregulating its expression, at least in part, in the macrophage foam cells. These results indicate that troglitazone potently inhibits fatty streak lesion formation by modulating both metabolic extracellular environments and arterial wall cell functions.

Animals↗
PubMed2001

Left ventricular relaxation abnormality is detectable by analysis of the relaxation time constant in patients with atrial fibrillation.

Left ventricular (LV) contractility is constantly changing during atrial fibrillation (AF), which is dependent on the force-interval relationships. However, no information has been available on LV relaxation in patients with both AF and impaired LV systolic function. LV pressure was measured with a catheter-tipped micromanometer and the time constant of isovolumic LV pressure decline (tau(bf)) was calculated with best exponential fitting from more than 10 consecutive beats. Patients with AF (5 with mitral valvular disease, 6 with idiopathic dilated cardiomyopathy, and 1 with no underlying disease) were subdivided into 2 groups: group A, with ejection fraction (EF) <0.5 (n=7); and group B, with EF > or =0.5 (n=5). Linear correlation coefficients (r) between tau and RR2, RR2/RR1, LV peak systolic pressure (peak LVP) were calculated. Although tau did not show a discrepancy between the 2 groups, tau(bf) correlated better with RR2/RR1 only in the group A patients. The relation between tau and peak LVP showed a good correlation with a steep slope (R, Deltatau/Deltapeak LVP) only in the group A patients (accentuated afterload-dependence). R was significantly different between the 2 groups. Thus, a beat-to-beat analysis of tau may be a practical and feasible way for detecting LV relaxation abnormality in patients with AF.

Adult↗
PubMed2001

Hypertrophic cardiomyopathy with midventricular obstruction and apical aneurysm: a case report.

A 71-year-old woman had hypertrophic cardiomyopathy associated with midventricular obstruction and an apical aneurysm in the left ventricle. She had had abnormal electrocardiograms for more than 30 years and for the past year had been suffering from occasional attacks of dizziness and low systemic blood pressure. Holter 24-h electrocardiographic monitoring revealed ventricular paroxysmal contractions (676/day) with nonsustained ventricular tachycardia. Doppler echocardiography revealed paradoxical jet flow from the apical aneurysm to the left ventricular outflow during early diastole. Magnetic resonance imaging depicted midventricular hypertrophy and a dyskinetic thin apical wall, which were confirmed by angiography. Coronary angiograms showed no narrowing of the major extramural coronary arteries, but there was compression of aberrant coronary arteries apparently feeding the hypertrophic portion of the left ventricular wall. Stress thallium-201 myocardial imaging showed a persistent severe defect in the left ventricular apex. A hemodynamic study revealed low cardiac output and an intraventricular pressure gradient (approximately 90 mmHg) between the left ventricular apical high-pressure chamber and the subaortic low-pressure chamber. The present case represents a rare combination of hypertrophic cardiomyopathy, midventricular obstruction, and an apical aneurysm in an elderly woman. Myocardial ischemia may have played an important role in the genesis of the apical aneurysm.

Aged↗
PubMed2001

Functional similarities of recombinant OLP and cytokinin-binding protein 2.

CBP1 and CBP2 are cytokinin-binding proteins isolated from tobacco callus. In particularly, CBP2 is a 26-kDa protein with high affinity (Kd=1.08 x 10(-6) M) for cytokinin [Kobayashi et al. Plant Cell Physiol.41(2): 148-157 (2000)] and the N-terminal amino acid analysis of CBP2 showed high sequence homology (92.9%) to tobacco osmotin-like protein (OLP). To compare the properties of OLP and CBP2, recombinant OLP was purified, and binding to benzyladenine (BA) was examined. The inclusion bodies of recombinant OLP were solubilized in 8 M urea and purified on an SP-Sepharose column. SDS-PAGE analysis of the purified recombinant OLP revealed a single band of 26 kDa. The Kd of solublized recombinant OLP to BA obtained from a Scatchard plot was 1.10 x 10(-6) M, which was similar to the Kd of CBP2 to BA (1.08 x 10(-6) M).

Amino Acid Sequence↗
PubMed2001

Noninvasive assessment of the early progression of atherosclerosis in adolescents with Kawasaki disease and coronary artery lesions.

OBJECTIVES: The severity of carotid arteriosclerosis, defined as increased intima-media thickness (IMT) visible with B-mode ultrasound, is correlated with risk factors for coronary heart disease. Little is known, however, about the relation of IMT, the stiffness of the common carotid artery, and the progression of atherosclerosis in children with Kawasaki disease (KD) and coronary artery lesions (CAL). DESIGN: We investigated the associations among total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglyceride, TC/HDL-C, ApoE genotype, glycohemoglobin, IMT, and arterial stiffness by high resolution ultrasound in 20 adolescents with KD and CAL (age: 16.6 +/- 4.1 years, males: 60%) and 20 sex- and age-matched healthy controls (Cont). RESULTS: No significant differences were observed in the values of body mass index and blood pressure between the 2 groups. Also no significant differences were observed in the levels of TC, LDL-C, HDL-C, triglyceride, TC/HDL-C within normal values, or the allele frequency of Apo E4 between the 2 groups. However, the values of IMT, stiffness, and glycohemoglobin in patients with KD were significantly higher than those in Cont (0.53 +/- 0.07 vs 0.46 +/- 0.05 mm, P <.05; 4.11 +/- 0.86 vs 2.94 +/- 0.91, P <.001; 5.0 +/- 0.4 vs 4.6 +/- 0.2%, P <.05). A significant relationship was observed between sex and the mean IMT (r = 0.46) in Cont; however, no significant correlation was found between mean IMT and other variables in either group. Although the arterial stiffness was strongly related to body mass index (r = 0.58) and systolic blood pressure (r = 0.55) in Cont, no significant relationship was observed between the stiffness and any variable tested in patients with KD. CONCLUSIONS: The less distensible carotid wall in patients with KD compared with that in Cont without major alteration of the lipid profile is likely to be secondary to the changes in arterial walls after a diffuse vasculitis involving noncoronary arteries. These results indicate that the coronary arteries may be predisposed to accelerated atherosclerosis in patients with KD and CAL.

Adolescent↗
PubMed2001

In situ morphometric analysis of left and right ventricles in fetal rats: changes in ventricular volume, mass, wall thickness, and valvular size.

We studied morphological changes in the left and right ventricles of fetal rats in late-gestation using rapid whole-body freezing technique. Pregnant Wistar rats (term, 21.5 day) were immediately frozen in liquid nitrogen on 17-, 18-, 19-, 20-, and 21-day of gestation. The frozen fetal hearts were serially sectioned with a sliding microtome and photographed. The ventricular volume, mass, wall thickness, and area of valvular orifice were measured on the photographs. During the study period, the left and right ventricular volumes increased very rapidly (9.9-fold and 7.6-fold, respectively) compared with the increase in the body weight (4.0-fold); the volumes divided by body weight increased linearly. Left and right ventricular masses also rapidly increased (5.9-fold and 5.0-fold, respectively). Mass/volume ratios for the two ventricles rapidly decreased. The wall thicknesses divided by body weights rapidly decreased with the progression of the gestational age. The left and right ventricles at 17 day of gestation have relative hypertrophy and relatively large valvular orifices as compared with those in terminal gestation. The improvement of the relative hypertrophy of the ventricles may indicate the morphological and functional maturation of the fetal heart.

Animals↗