Biomedical subjects

H Fukuda

Publications and source records attributed to H Fukuda.

At least 19 recordsLinked to original sources

PubMed2006

Role(s) of nucleoli and phosphorylation of ribosomal protein S6 and/or HSP27 in the regulation of muscle mass.

Effects of 14 days of hindlimb unloading or synergist ablation-related overloading with or without deafferentation on the fiber cross-sectional area, myonuclear number, size, and domain, the number of nucleoli in a single myonucleus, and the levels in the phosphorylation of the ribosomal protein S6 (S6) and 27-kDa heat shock protein (HSP27) were studied in rat soleus. Hypertrophy of fibers (+24%), associated with increased nucleolar number (from 1-2 to 3-5) within a myonucleus and myonuclear domain (+27%) compared with the preexperimental level, was induced by synergist ablation. Such phenomena were associated with increased levels of phosphorylated S6 (+84%) and HSP27 (+28%). Fiber atrophy (-52%), associated with decreased number (-31%) and domain size (-28%) of myonuclei and phosphorylation of S6 (-98%) and HSP27 (-63%), and with increased myonuclear size (+19%) and ubiquitination of myosin heavy chain (+33%, P > 0.05), was observed after unloading, which inhibited the mechanical load. Responses to deafferentation, which inhibited electromyogram level (-47%), were basically similar to those caused by hindlimb unloading, although the magnitudes were minor. The deafferentation-related responses were prevented and nucleolar number was even increased (+18%) by addition of synergist ablation, even though the integrated electromyogram level was still 30% less than controls. It is suggested that the load-dependent maintenance or upregulation of the nucleolar number and/or phosphorylation of S6 and HSP27 plays the important role(s) in the regulation of muscle mass. It was also indicated that such regulation was not necessarily associated with the neural activity.

Animals↗

PubMed2006

A case of glossopharyngeal zoster diagnosed by detecting viral specific antigen in the pharyngeal mucous membrane.

Glossopharyngeal nerve paralysis caused by varicella zoster virus reactivation is rare. We present a case of glossopharyngeal zoster confirmed by direct immunofluorescence staining for virus antigens. A 35-year-old man presented with right-sided, severe swallowing pain and dysgeusia. Physical examination showed a loss of ipsilateral gag reflex. White spots on the posterior wall of the right pyriform sinus were seen by laryngofibroscopy, and a loss of taste on the right posterior part of the tongue was confirmed by gustometry using the filter paper disc method. The varicella zoster virus antigen was revealed by direct immunofluorescence staining by fluorescein isothiocyanate labelled mouse monoclonal antibody specific for varicella zoster virus glycoprotein, using samples obtained from the mucosal lesion by abrasion with a cotton swab. The patient was treated by intravenous administration of acyclovir. His throat pain and dysgeusia completely resolved. We discuss the advantages of direct immunofluorescence staining for varicella zoster virus antigen for the diagnosis of glossopharyngeal zoster.

Acyclovir↗

PubMed2006

Diffuse cerebral white matter T2-weighted hyperintensity: a new finding of general paresis.

General paresis (parenchymatous neurosyphilis) is a rare disease, and in recent years the number of papers published on the magnetic resonance imaging findings has been limited. The findings are as follows: cerebral atrophy; mesiotemporal T2 hyperintensity; ventriculomegaly; pathological T2 hypointensity of the globus pallidus, putamen, the head of the caudate nucleus and thalamus. We present a new finding, diffuse cerebral white matter T2 hyperintensity, observed in a patient with general paresis with a 5-year history of progressive dementia.

Adult↗

PubMed2006

[Intermediate results of aortic valve replacement using 19 mm bioprosthetic valve].

Pre- and postoperative hemodynamic parameters and activity of daily life were reviewed to estimate the effectiveness of the valve in 12 cases of single aortic valve replacement (AVR) using 19 mm bioprosthesis. All implanted prostheses were stented-valves. Carpentier-Edwards pericardial valve was used in 7 cases and Mosaic valve in 5. Left ventricular mass index (LVMI) significantly decreased from 167 +/- 36 to 133 +/- 27 g/m2 in the early postoperative period, and to 115 +/- 24 g/m2 in the intermediate phase. However, postoperative LVMI remained higher in patients with body surface area (BSA) over 1.5 m2 than in those under 1.5 m2. Postoperative activity indicated by New York Heart Association (NYHA) grade significantly improved from 2.3 +/- 1.1 to 1.4 +/- 0.5. These results indicates usefulness of 19 mm bioprosthetic valve for reducing left ventricular hypertrophy and improving activity, especially in patients with BSA smaller than 1.5 m2.

Aged↗

PubMed2005

Carbonization of waste PVC to develop porous carbon material without further activation.

Efficient removal of chlorine from PVC achieved by two-stage heat-treatment (280 and 410 degrees C) provided chlorine-free isotropic pitch containing additive. The pitch was stabilized and carbonized into porous carbons with surface areas of approximately 300 m2/g. Resultant porous carbons showed three pore structures of supermicropore, micropore and mesopore. The generation of CO2 from the decomposition of the CaCO3 additive in waste PVC is responsible for the development of porous structures. The surface area of the carbonized product increased after the removal of CaO.

Adsorption↗

PubMed2005

Helicobacter pylori infection and platelet counts during pregnancy.

OBJECTIVE: To investigate whether there is any correlation between Helicobacter pylori infection and platelet counts during pregnancy. METHODS: One hundred and twenty pregnant women without any complications were evaluated. Platelet counts were determined during pregnancy and postpartum. H. pylori infection was assessed by the detection of serum antibodies at the 3rd day postpartum. Statistically significant differences of platelet count between H. pylori-positive and -negative patients were determined. RESULTS: H. pylori infection was found in 29 of 120 (24.2%). Platelet counts in the 3rd trimester were 22.7+/-4.7 x 10(3)/microl in H. pylori-positive group and 22.8+/-5.6 x 10(3)/microl in negative group (p=0.98). Platelet count in the 3rd trimester in positive and negative patients were 93+/-17% and 94+/-20%, respectively, of that of the 1st trimester (p=0.92). The incidence of hyperemesis gravidarum in both groups was not significant (p=0.28). CONCLUSION: A correlation between H. pylori infection and thrombocytopenia during pregnancy was not found in this study.

Female↗

PubMed2005

Malate dehydrogenase activities are lower in some types of peripheral leucocytes of dogs and cats with type 1 diabetes mellitus.

The activities of the enzymes in the malate-aspartate shuttle were measured in peripheral leucocytes of spontaneous type 1 diabetic dogs and cats treated with insulin injections. In the diabetic dogs and cats, fasting plasma glucose concentrations were three- or fourfold greater than the control levels in spite of insulin injections and the activities of cytosolic malate dehydrogenase (MDH), one of pivotal enzymes in the malate-aspartate shuttle, were remarkably lower than the controls. Depressed expression of cytosolic MDH mRNA was confirmed by RT-PCR analysis in the diabetic animals. The cytosolic ratio of MDH/lactate dehydrogenase (LDH) activity (M / L ratio) in leucocytes of the diabetic animals was significantly lower than that of normal control animals. The smaller M / L ratio appeared to reflect depression of energy metabolism in the diabetic animals. Intrinsically lower and further decreased MDH activities may be factors that induce insulin resistance observed in diabetic cats.

Animals↗

PubMed2005

Diffusion tensor imaging of cerebral white matter in patients with myotonic dystrophy.

PURPOSE: To determine whether myotonic dystrophy (MyD) patients have diffusion tensor abnormalities suggestive of microstructural changes in normal-appearing white matter (NAWM). MATERIAL AND METHODS: Conventional and diffusion tensor magnetic resonance images of the brain were obtained in 19 MyD patients and 19 age-matched normal control subjects. Fractional anisotropy (FA) and mean diffusivity (MD) values were calculated in white matter lesions (WMLs) and NAWM in MyD patients and in the white matter of normal control subjects. Differences between WML and NAWM values and between MyD patient and control subject values were analyzed statistically. RESULTS: Significantly lower FA and higher MD values were found in all regions of interest in the NAWM of MyD patients than in the white matter of control subjects (P<0.01), as well as significantly lower FA and higher MD values in WMLs than in NAWM of MyD patients (P < 0.05). There was no significant correlation of mean FA or MD values in NAWM with patient age, age at onset, or duration of illness (P>0.1). CONCLUSION: Diffusion tensor imaging analysis suggests the presence of diffuse microstructural changes in NAWM of MyD patients that may play an important role in the development of disability.

Adult↗

PubMed2005

Impaired gastric motor activity after abdominal surgery in rats.

Postoperative ileus (POI) is a transient bowel dysmotility that occurs following abdominal surgery. Several mechanisms have been proposed such as neural reflex and inflammatory changes. We focused on gastric motility after abdominal surgery in rats. To investigate the time course of gastric motility after surgery, gastric motility was continuously recorded before, during and after surgery. After laparotomy, terminal ileum was manipulated for 10 min. Gastric motility was recorded by a strain gauge transducer implanted on the serosal surface of the stomach. To investigate whether peripheral sympathetic nerve is involved in the pathogenesis of POI, effects of guanethidine and celiac ganglionectomy were tested on the postoperative gastric motility. Although isoflurane anaesthesia reduced the gastric motility to 40%, the motility recovered immediately when isoflurane was withdrawn. Intestinal manipulation reduced the postoperative gastric motility for 3-24 h after surgery, compared with preoperative levels. Guanethidine administration and celiac ganglionectomy restored the impaired gastric motility. Feeding increased the gastric motility in each group. It is suggested that the pathogenesis of postoperative gastric ileus induced by intestinal manipulation involves viscero-sympathetic pathways. Intestinal manipulation causes impaired gastric motility via inhibitory sympathetic efferent pathway. Feeding may improve the postoperative gastric motility.

Adrenergic Agents↗

PubMed2004

Lysis of adhesions and epidural injection of steroid/local anaesthetic during epiduroscopy potentially alleviate low back and leg pain in elderly patients with lumbar spinal stenosis.

BACKGROUND: Lumbar spinal stenosis causes various forms of back or leg pain, and is recognized with increasing frequency in elderly patients whose physical status is not always suitable for surgery. Epiduroscopy, a new, minimally invasive diagnostic and therapeutic technique, may be useful for pain relief in such patients. We investigated the epiduroscopic findings and immediate and long-term changes in back and leg pain after epiduroscopy in elderly patients with spinal stenosis. METHODS: Patients with degenerative lumbar spinal stenosis (n=58, median age 71 yr) were divided into two groups based on presenting symptoms: a monosegmental group (n=34) and a multisegmental group (n=24). Each patient underwent epiduroscopy, and the findings were evaluated using visual analogue scales for low back and leg symptoms. Epiduroscopy included breaking down adhesions in the epidural space by injections of saline, and injection of steroids/local anaesthetic. RESULTS: Epiduroscopy showed that the amount of fatty tissue and the degree of vascularity were greater in the monosegmental group than in the multisegmental group. Relief of low back pain was observed up to 12 months after epiduroscopy in both groups. Relief of leg pain was evident up to 12 months after epiduroscopy in the monosegmental group, and up to 3 months after epiduroscopy in the multisegmental group. None of the patients showed deterioration of motor or sensory deficits during follow-up. One patient was excluded from analysis because of accidental dural puncture during the procedure. CONCLUSIONS: The findings of epiduroscopy corresponded to the symptoms. Epiduroscopy may reduce low back and leg pain in elderly patients with degenerative lumbar spinal stenosis, particularly those with radiculopathy.

Aged↗

PubMed2004

Porphyrin synthesis from ALA derivatives for photodynamic therapy. In vitro and in vivo studies.

The aim of this work was to test in vitro and in vivo the efficacy of the derivatives of 5-aminolevulinic acid (ALA): hexyl-ALA (He-ALA), undecanoyl-ALA and R,S-2-(hydroximethyl)tetrahydropyranyl-ALA (THP-ALA) as pro-photosensitising agents. The compounds were assayed in a cell line derived from a murine mammary tumour, in tumour explants and after injection of the cells into mice. In vitro, undecanoyl-ALA and THP-ALA did not improve ALA efficacy in terms of porphyrin synthesis. On the other hand, half of the amount of ALA is required to obtain the same plateau amount of photosensitiser from He-ALA. However, this plateau value cannot be surpassed in spite of the four-times higher accumulation of ALA/He-ALA from the ALA derivative. This shows that He-ALA conversion to porphyrins but not He-ALA entry to the cells is limiting. Employing ionic exchange chromatography, we found that 80% of total uptake was He-ALA whereas only 20% was ALA. This suggests that the esterases, probably themselves regulated by the heme pathway, are limiting the conversion of ALA derivatives into porphyrins. A similar situation occurs with THP-ALA. Tumour explant porphyrin results correlate well with cell line data. However, i.p. injection of ALA derivatives to mice resulted in a lower porphyrin concentration in the tumour when compared to the administration of equimolar amounts of ALA, indicating that there should be retention of ALA derivatives either within the blood vessels in the initial phase of distribution and/or within the capillaries of the tumour.

Aminolevulinic Acid↗

PubMed2004

Enantioselective transesterification using immobilized Aspergillus oryzae overexpressing lipase.

In the present study, we used gene manipulation to construct a recombinant Aspergillus oryzae strain overexpressing lipase and investigated its application to the optical resolution of chiral compounds. A. oryzae niaD300, which was derived from the wild-type strain RIB40, was used as the host strain. The tglA gene, which encodes a triacylglycerol lipase, was cloned from the A. oryzae niaD300 chromosomal genome, then reintroduced, with and without a secretion-signal sequence, into the genome and expressed under the control of the improved glaA promoter of plasmid pNGA142. The resulting recombinant strain overexpressing A. oryzae lipase was immobilized within biomass-support particles and used as a whole-cell biocatalyst. The immobilized lipase-overexpressing strain with secretion-signal sequence showed high activity and was used to selectively synthesize (R)-1-phenylethyl acetate from (RS)-1-phenylethanol and vinyl acetate. After 48 h reaction at 30 degrees C with molecular sieve 4A, the yield and enantiomeric excess (%ee) of (R)-1-phenylethyl acetate reached approximately 90 and 95%ee, respectively. The whole-cell biocatalyst for optical resolution of chiral compounds produced in this study maintained its activity over 25 batch-reaction cycles.

Aspergillus oryzae↗

PubMed2004

Over-expression system for secretory phospholipase D by Streptomyces lividans.

The structural gene for phospholipase D (PLD) of an actinomycete, Streptoverticillium cinnamoneum, together with its promoter region was introduced into Streptomyces lividans using a shuttle vector-pUC702-for Escherichia coli and S. lividans. The transformant was found to secrete a large amount of PLD (about 2.0x10(4) U/l, 42 mg/l) when cultured in a jar fermentor. Both an initial glucose concentration of 17.5 g/l and the feeding of carbon and nitrogen sources are effective for efficient secretion of PLD; under these culture conditions, the amount of PLD secreted reached a maximum level (about 5.5x10(4) U/l, 118 mg/l) after about 60 h. In contrast to the original producer, Stv. cinnamoneum, which secretes only a small amount of PLD (about 1.1x10(3) U/l, 2 mg/l) along with other extracellular proteins, this heterologous expression system is markedly more efficient in production of secretory PLD.

Actinobacteria↗

PubMed2004

Improvement of scopolamine-induced memory impairment by Z-ajoene in the water maze in mice.

Z-ajoene, a major compound containing sulfur in oil-macerated garlic products, exhibited inhibitory effects against scopolamine-induced memory impairment in mice using the Morris water maze test. The effects of Z-ajoene were observed dose-dependently (0.25-25 mg/kg). At the highest dosage, the memory performance of mice was improved compared to normal mice. The acetylcholinesterase (AChE) activity in the brain was reduced by administration of Z-ajoene dose-dependently. However, alliin and diallyl disulfide, organosulfur compounds from garlic, did not improve memory performance nor AChE inhibitory effect. These results suggest that Z-ajoene may act on the cholinergic system and on memory impairment caused by excess activity of AChE.

Acetylcholinesterase↗

PubMed2004

Irradiation-induced progenitor cell death in the developing brain is resistant to erythropoietin treatment and caspase inhibition.

One hemisphere of postnatal day 8 (P8) rats or P10 mice was irradiated with a single dose of 4-12 Gy, and animals were killed from 2 h to 8 weeks after irradiation (IR). In the subventricular zone (SVZ) and the granular cell layer (GCL) of the dentate gyrus, harboring neural and other progenitor cells, nitrosylation and p53 peaked 2-12 h after IR, followed by markers for active caspase-3, apoptosis-inducing factor and TUNEL (6-24 h). Ki67-positive (proliferating) cells had disappeared by 12 h and partly reappeared by 7 days post-IR. The SVZ and GCL areas decreased approximately 50% 7 days after IR. The development of white matter was hampered, resulting in 50-70% less myelin basic protein staining. Pretreatment with erythropoietin did not confer protection against IR. Caspase inhibition by overexpression of XIAP prevented caspase-9 and caspase-3 activation but not cell death, presumably because of increased caspase-independent cell death.

Active Transport, Cell Nucleus↗

PubMed2004

A comparison of the effects of prolonged (>10 hour) low-flow sevoflurane, high-flow sevoflurane, and low-flow isoflurane anaesthesia on hepatorenal function in orthopaedic patients.

This study compared the effects of low-flow sevoflurane, high-flow sevoflurane and low-flow isoflurane on hepatorenal function during and after more than 10 hours of anaesthesia. Twenty-five patients scheduled for elective orthopaedic surgery were categorized into three groups; low-flow sevoflurane (fresh gas flow at 1 litre/min, n = 9), high-flow sevoflurane (5 l/rmin, n = 7), or low-flow isoflurane (1 l/min, n=9). Inspiratory compoundA concentrations were measured. The groups had similar duration of anaesthesia and exposure to anaesthetic agents. The area under the curve of concentration (mean, SD) of compound A in the low-flow sevoflurane group (359.8, 106.1 ppm.h) was greater than that in the high-flow sevoflurane group (61.1, 29.3 ppm.h; P<0.01). All groups showed normal plasma creatinine and creatinine clearance, and transient postoperative increases in plasma alanine aminotransferase and alpha glutathione-S-transferase, as well as urinary glucose and alpha glutathione-S-transferase, with no significant differences between groups. There were no significant relationships between the area under the curve of concentration of compound A and the biomarkers. These findings suggest that prolonged anaesthesia with low-flow sevoflurane has similar effects on hepatorenal function to prolonged anaesthesia with high-flow sevoflurane and low-flow isoflurane.

Adult↗

PubMed2004

Microneurographically recorded Ia discharge from the tibial nerve mainly transmits the angular velocity of the ankle joint in humans.

Investigations of the Ia afferent discharge in clarifying problems in disused and malused skeletal muscles have been carried out mainly in muscles of the upper extremities. However, such problems actually occur more frequently in the antigravity muscles of the lower extremities, such as the triceps surae muscle. An analysis of microneurographically recorded Ia discharges from the tibial nerve innervating the triceps surae muscle during dynamic movement of the ankle joint indicated that they mainly transmitted information on the angular velocity of the joint. However, the information on the position sense of the joint was not as well transmitted through Ia discharges. There was no correlation between the joint angle and the static response. However, the dynamic response of a Ia afferent was well correlated to the angular velocity. It is concluded that the human proprioception of the triceps surae muscle was not dependent on the position of the ankle joint, but largely on its movement by the stretching of the muscle.

Adult↗

PubMed2004

Ghrelin enhances gastric motility through direct stimulation of intrinsic neural pathways and capsaicin-sensitive afferent neurones in rats.

BACKGROUND: Ghrelin may stimulate gastric motility via the vagal nerve pathway. However, the mechanism of ghrelin-induced changes in gastrointestinal motility has not yet been clearly defined. The present study was designed to investigate whether ghrelin accelerates gastric emptying via capsaicin-sensitive afferent neurones and directly affects the enteric neuromuscular function. METHODS: Gastric emptying of nutrient solids was assessed after intravenous administration of saline or ghrelin in conscious rats. The effects of ghrelin on gastric emptying were also examined in rats pretreated with capsaicin. Gastric emptying and intestinal transit of non-caloric liquids were evaluated using 51Cr solution. The effects of ghrelin on spontaneous contractile activities of isolated strips from stomach and jejunum were also investigated and the influence of ghrelin on motor responses to carbachol and electrical field stimulation was examined. RESULTS: Ghrelin significantly accelerated gastric emptying of both nutrient solids and non-caloric liquids in conscious rats. The intestinal transit of non-caloric liquids was also enhanced by ghrelin. Pretreatment with capsaicin prevented the ghrelin-induced acceleration of gastric emptying of nutrient solids. Ghrelin did not modulate spontaneous and carbachol-induced contractions of strips of gastric body, gastric antrum and jejunum. However, electrical field stimulation-induced contractions were significantly enhanced by ghrelin in the gastric body. CONCLUSIONS: The results suggest that the stimulatory effects of ghrelin on gastric motility are mediated by direct stimulation of the enteric neural pathway and capsaicin-sensitive afferent neurones.

Afferent Pathways↗