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M Okada

Publications and source records attributed to M Okada.

At least 19 recordsLinked to original sources
PubMed2006

Detection and sequence-based typing of human adenoviruses using sensitive universal primer sets for the hexon gene.

The universal primer sets for identification of human adenovirus (HAdV) targeting hexon gene were designed and applied to 121 clinical samples suspected of HAdV infection. The primer sets amplified at least 20 HAdV reference strains of six species. Of these clinical samples, 81 (66.9%) samples were positive for HAdV. They were classified into 11 serotypes belonging to 5 HAdV species (B-F). The primer sets described here are sensitive and reactive to the broad spectrum of HAdV and are useful for rapid diagnosis of various HAdV infections.

Adenovirus Infections, Human↗
PubMed2006

The detection of human sapoviruses with universal and genogroup-specific primers.

Sapovirus (SV) causes gastroenteritis in humans and comprises genetically divergent viruses. A nested reverse transcription-polymerase chain reaction (RT-PCR) targeting the capsid-protein-coding region was developed using universal and genogroup-specific primer sets. The universal primers were capable of detecting human SV genogroups I, II, IV and V. Genetic analysis of the amplified products enabled us to phylogenetically determine the genotypes of the viruses. In addition, genogroup-specific primers that amplified different lengths of the amplicon depending on the genogroup were developed. These genogroup-specific primers were also used as inner primers for the nested PCR. These two simple RT-PCR methods are powerful tools for both detection and epidemiological studies of human SV.

Caliciviridae Infections↗
PubMed2006

Organic carbon leaching behavior from incinerator bottom ash.

The understanding of the leaching behavior of organic carbon from incinerator bottom ash is an important aspect for the control of organic carbon emissions from landfills in order to minimize their potential risk to the environment. The leaching behavior of organic carbon from incinerator bottom ash samples, obtained from two different solid waste sources, as well as the effects of calcium (Ca) on organic carbon (DOC) leaching associated with pH were therefore investigated in this paper. The effect of pH on the leaching of DOC and other major elements from bottom ash was ascertained through pH-stat leaching experiments. Column leaching experiments were carried out to evaluate the dependence of the leached amount of DOC on Ca leaching. It was found that the bottom ash produced by incineration of municipal solid waste (MSW) was composed of two DOC fractions: DOC leached independent (fraction I) of Ca leaching, observed at alkaline-neutral pH, and DOC leached dependent (fraction II) on Ca leaching, observed at acid pH. However, the bottom ash produced by incineration of industrial solid waste (ISW) was composed of only DOC fraction I. The addition of calcium oxide during incineration and the differences in the paper to plastic ratio in the physical composition of the solid wastes incinerated would explain the distinct organic carbon leaching behaviors of bottom ash samples.

Calcium↗
PubMed2006

Genetic analysis of noroviruses associated with fatalities in healthcare facilities.

Norovirus outbreaks occurred in 236 healthcare facilities for the elderly in Japan during the winter of 2004-2005. Three norovirus strains associated with three fatal clinical courses were isolated from geographically separate facilities and genetically analyzed along with three strains from non-fatal cases in the same season. All six isolates were classified as the GII-4 genotype. No new variant strains like those observed in Europe in 2002 and 2004 were found in fatal cases, and the three outbreaks were deemed to have been caused by genetically close conventional norovirus GII-4 strains.

Aged, 80 and over↗
PubMed2006

Quantitative analysis of amyloid plaques in a mouse model of Alzheimer's disease by phase-contrast X-ray computed tomography.

Densely aggregated beta-amyloid peptides are believed to play a key role in the pathogenesis of Alzheimer's disease. Amyloid plaques are a potential target for molecular imaging to determine the clinical status of Alzheimer's disease. Phase-contrast X-ray imaging combined with computed tomography is a promising technique that can be used to visualize the physical density of structures in biological tissues non-invasively, and without the use of imaging agents. Using brain tissue isolated from a mouse model of Alzheimer's disease, we show that beta-amyloid 40-positive/beta-amyloid 42-positive amyloid plaques, but not beta-amyloid 40-negative/beta-amyloid 42-positive amyloid plaques, exist as high-density aggregates that can be specifically detected by phase-contrast X-ray computed tomography. The phase-contrast X-ray computed tomography detected beta-amyloid 40-positive/beta-amyloid 42-positive amyloid plaques in three-dimensions with an extremely high sensitivity comparable to that of histological analysis, and also enabled the load of amyloid plaques to be quantified. Furthermore, the use of phase-contrast X-ray computed tomography reveals that the physical density of beta-amyloid 40-positive/beta-amyloid 42-positive amyloid plaques increases with age, and that the large volume, high-density, amyloid plaques that are specifically observed in aged Alzheimer's disease mice are closely associated with neuritic dystrophy. These results demonstrate that phase-contrast X-ray computed tomography is a highly sensitive imaging technique for analyzing dense-cored amyloid plaques in postmortem samples, and is beneficial in elucidating amyloid pathophysiology in Alzheimer's disease.

Aging↗
PubMed2006

Biphasic clinical course and early white matter abnormalities may be indicators of neurological sequelae after status epilepticus in children.

Clinical course and serial neuroimaging findings are not fully described in children who have had neurological sequelae following status epilepticus. We found four patients who had neurological sequelae out of 42 children with status epilepticus in 2004. MRI studies were reviewed with specific attention to diffusion-weighted images (DWI) and the apparent diffusion coefficient (ADC). Proinflammatory cytokines, including tumor necrosis factor-alpha and interleukin-6, were measured in the cerebrospinal fluid (CSF) (3 patients). The clinical course showed biphasic; initial status epilepticus and neurological exacerbation along with seizure recurrence four to five days after onset. Within three days after initial status epilepticus, CT (all patients) and MRI (2 patients) did not show any abnormalities. From four to ten days after onset, MRI demonstrated diffuse hyperintensity in the cerebral white matter on DWI and hypointensity on ADC maps in all patients. Diffuse brain atrophy progressed thereafter. Tumor necrosis factor-alpha or interleukin-6 was elevated in all patients. A biphasic clinical course may be a specific feature for neurological sequelae. The preferential white matter involvement on MRI and elevated CSF cytokines indicate that glial dysfunction may play an important role in the pathophysiology of status epilepticus-associated cerebral damage.

Brain Mapping↗
PubMed2006

Posterior endoscopic surgery for lumbar disc herniation with contralateral symptoms - a report of two cases.

We report two cases of lumbar disc herniation with contralateral nerve root involvement, surgically treated with a microendoscopic disectomy system (METRx-MED system). The nerve root of the symptomatic side (contralateral to the side of the disc herniation) had been compressed to the superior facet by herniated disc from the opposite side. Endoscopic observation revealed inflammatory findings of the nerve root on the symptomatic side, such as fibrosis, adhesion, redness and swelling. In contrast, on the non-symptomatic side (ipsilateral side of the disc herniation), the nerve root had been merely compressed by the herniated disc but did not demonstrate any inflammatory findings. Excision of the herniated disc and decompression of the non-symptomatic nerve root should be done first, approaching from the disc herniation side. After that, through the same approach, the nerve root of the opposite (symptomatic) side should be decompressed.

Adolescent↗
PubMed2006

Proposal for a standardized protocol for the systematic orofacial examination of patients with Hereditary Sensory Radicular Neuropathy.

AIM: To apply a standardized protocol for the orofacial evaluation of two adult siblings (one male and one female) with Hereditary Sensory Radicular Neuropathy (HSRN) that presented with dental problems. SUMMARY: The systematic evaluation consisted of (a) clinical questionnaire; (b) radiographs [orthopantomography and computarized tomography (CT)]; (c) orofacial psychophysical tests (pain, thermal, mechanical and electrical sensation); and (d) histology of gingiva and pulp (optical and transmission electronic microscopy). The female patient had complete insensitivity to orofacial pain and partial facial heat sensitivity, and received dental treatment without anaesthesia or pain. She had a severe and painless jaw infection due to pulp necrosis in tooth 37. The male patient had partial insensitivity to orofacial pain and required anaesthesia for dental treatment. Histological examination of gingivae and pulpal tissue revealed an altered proportion of unmyelinated and myelinated sensory nerve fibres. KEY LEARNING POINTS: * Patients with HSRN may present with significant, silent dental disease. * A standard protocol is helpful when evaluating such patients. * If the opportunity arises, evaluation of pulp tissue may reveal an altered proportion of myelinated and unmyelinated nerve fibres. This may avoid the more estabilished sural nerve biopsy.

Adolescent↗
PubMed2006

MRI findings of haematomyelia in a dog with spontaneous systemic haemorrhage.

A 7-year-old female cross-breed dog was brought to Nihon University Animal Medical Center for investigation of tetraplegia. Lameness in the pelvic limbs, that had developed 2 weeks previously, had progressed to tetraplegia. On magnetic resonance imaging of the spinal cord, isointensity was detected from C2 to C4 and T12 to T13, isointensity and hyperintensity were intermingled from L3 to L4, and hyperintensity was detected from L5 to L7 by T1-weighted imaging. On T2-weighted imaging, hyperintensity was detected in all regions described above. The dog recovered from anaesthesia, but died during the day from systemic bleeding as the result of a coagulopathy of unknown aetiology. Histopathological examination revealed haematomyelia in these regions of the spinal cord. This is the first report of magnetic resonance imaging findings of haematomyelia in canine spontaneous systemic haemorrhage. It appeared that the differences in the findings of T1-weighted imaging along the spinal regions reflected time-lags in the occurrence of bleeding.

Animals↗
PubMed2006

Clinical outcome of extrasynovial steroid injection for trigger finger.

A prospective clinical study was performed to investigate the clinical results of extrasynovial (subcutaneous) steroid injection for trigger finger. One hundred and twenty-nine trigger fingers were investigated in 100 adult patients; 76 were women and 24 were men. Their mean age was 60 years (range: 17 to 88 years). We classified trigger fingers into three different grades according to clinical severity at a medical examination. All patients were injected with betamethasone mixed with lidocaine. Surgical release of the A1 pulley was performed at the patients' request if steroid injection therapy was not effective. Pain and snapping were relieved in 98% and 74% of cases, respectively. Recurrence occurred in about half our patients, but the same clinical benefit was obtained after re-injection. Surgery was performed for seven fingers. No complications of steroid injections were observed. This study suggests that extrasynovial steroid injection is a valuable conservative treatment for trigger finger and it is not necessary to try and inject into the tendon sheath to get a good result and markedly reduce the risk of causing damage to tendons and other structures.

Adolescent↗
PubMed2006

Simultaneous colorectal and liver resections for synchronous colorectal metastases.

BACKGROUND: The surgical strategy for the treatment of colorectal cancer and synchronous hepatic metastases remains controversial. Many surgeons fear anastomotic leakage and intraperitoneal abscesses when performing a one-step procedure. They prefer a two-step procedure with a liver resection 2 to 3 months after resection of the colorectal primary lesion. SUBJECTS AND METHODS: We analysed medical records from April 1994 to April 2002 for a total of 42 patients with colorectal cancer and synchronous liver metastases who underwent simultaneous liver and colorectal resections with a primary anastomosis. Special attention was paid to data on surgical procedures, postoperative morbidity, and mortality. RESULTS: Forty-two patients, 24 men and 18 women, were studied. Median operating time was 6.50 hours (3.75-11.0 hours), and median blood loss was 1522 ml (range 288 to 5650 ml). Postoperative complications included pleural effusion in 4 patients, ileus in 3, anastomotic leakage in 2, intraperitoneal pelvic abscesses in 1, pneumonia in 1, bile leakage in 1, atelectasis in 1, and wound infection in 1. There was no perioperative mortality. CONCLUSION: Simultaneous colorectal resection with a primary anastomosis and hepatectomy for synchronous liver metastases is considered a safe procedure.

Adult↗
PubMed2006

[High-pressure suction drainage for poststernotomy mediastinitis].

We present a case of high-pressure suction drainage for poststernotomy mediastinitis. A 67-year-old man who underwent coronary artery bypass grafting because of angina pectoris was noted massive dirty exudate fluid (putrid secretions) from median sternal wound on the 6th postoperative day. The sternal wounds were completely reopened and all sternal wires removed. Thorough debridement was performed. The mediastinum was then washed out with warn normal saline. The polyurethane foam was shaped to fit the resulting sternal defect and placed within the cavity just below the skin edge. The suction tube was inserted inside the foam and the area was covered with the adhesive drape. After 45 days suction drainage the sternal wound was closed, after which he was discharged.

Aged↗
PubMed2006

A modified method of activity-based costing for objectively reducing cost drivers in hospitals.

OBJECTIVES: Activity-based costing (ABC) is widely used to precisely allocate indirect costs to medical services. In the ABC method, the indirect cost is divided among the medical services in proportion to the volume of "cost drivers", for example, labor hours and the number of hours of surgery. However, the workload of data collection of cost drivers can be time-consuming and a considerable burden if there are many cost drivers. The authors aim to develop a method for objectively reducing the cost drivers used in the ABC method. METHODS: In the ABC method, the cost driver is assigned for each activity. We assume that these activities and cost drivers are the best combination. Our method, that is cost driver reduction (CDR), can objectively select surrogates of the cost drivers for each activity in ABC from candidate cost drivers. Concretely, the total indirect cost of an activity is temporarily allocated to the medical services using each candidate of cost drivers. The difference between the costs calculated by each candidate and the proper cost driver used in ABC is calculated to evaluate the similarity by the evaluation function. RESULTS: We estimated the cost of laboratory tests using our method and revealed that the number of cost drivers could be reduced from seven in the ABC to four. Similarly, the results of cost estimation obtained by our method were as accurate as those calculated using the ABC. CONCLUSIONS: Our method provides two advantages compared to the ABC method: 1) it provides results that are as accurate as those of the ABC method, and 2) it is simpler to perform complicated estimation of hospital costs.

Accounting↗
PubMed2005

Chemical extraction of organic carbon to reduce the leaching potential risk from MSWI bottom ash.

The performance of extraction solvents, including organic and inorganic solvents, for organic carbon extraction from municipal solid waste incinerator (MSWI) bottom ash was evaluated. The total carbon (TC) extracted was used to ascertain the efficiency of extraction solvents and the reduction of dissolved organic carbon (DOC) leaching potential was used to evaluate the capacity of solvents to minimize environmental impacts of MSWI bottom ash over short- and long-term considerations in landfill sites. Extract final pH value was a prominent parameter affecting TC extraction. The higher efficiency was obtained at the lower extract final pH and acid or neutral condition was necessary to achieve approximately 30% of TC extraction from bottom ash. On the basis of the results of TC extraction, the efficiency of organic carbon reduction was evaluated using organic carbon leaching potential. Hydrochloric acid was the best solvent to extract organic carbon in controlled pH conditions. Hydrochloric acid reduced the organic carbon leaching potential of MSWI bottom ash by about 68% at neutral leaching pH.

Carbon↗
PubMed2005

Angiotensin II augmented migration and invasion of choriocarcinoma cells involves PI3K activation through the AT1 receptor.

While angiotensin II (Ang II) has been shown to inhibit migration of extravillous trophoblasts via plasminogen activator inhibitor-1 (PAI-1) activation, it has remained unclear whether it stimulates or inhibits malignant behavior of choriocarcinoma cells. Since we previously found an involvement of the renin-angiotensin system (RAS) in the proliferative potential in choriocarcinoma cells (BeWo), mediated via the Ang II type 1 receptor (AT1R), in the present study we investigated the effects of Ang II on choriocarcinoma cell migration/invasion in vitro using Transwell cell culture chambers. Ang II (10(-8)M) promoted migration and invasion by a choriocarcinoma cell line and augmented random cell mobility on checkerboard analysis. Immunoblotting showed Ang II to activate the phosphorylation of FAK and Akt in BeWo cells. Furthermore Ang II effects on cell migration were abolished by a selective AT1R antagonist and a phosphatidylinositol 3-kinase (PI3K) inhibitor. The present results suggest that Ang II-induced migration and invasion of choriocarcinoma cells probably involves PI3K following binding to the AT1R.

Angiotensin II↗
PubMed2005

A case of toe macrodactyly treated by application of a vascularised nail graft.

Macrodactyly is a relatively rare congenital abnormality of the fingers and toes and is difficult to treat. We report a new method for treating toe macrodactyly in which a nail with a vascularised pedicle is raised, the toe is shortened to an appropriate length, and the nail transferred to an aesthetically appropriate proximal site. Although this technique is of a higher level of difficulty than conventional procedures involving pedicled nail flaps, allows aesthetically more favourable nail reconstruction by single-stage operation.

Adult↗
PubMed2005

Biphasic actions of topiramate on monoamine exocytosis associated with both soluble N-ethylmaleimide-sensitive factor attachment protein receptors and Ca(2+)-induced Ca(2+)-releasing systems.

To explore the pharmacological mechanisms of topiramate (TPM), we determined the effects of TPM on monoamine (dopamine and serotonin) exocytosis associated with N-ethylmaleimide-sensitive factor attachment protein receptors and Ca(2+)-induced Ca(2+)-releasing systems, including inositol-triphosphate receptor and ryanodine receptor in freely moving rat pre-frontal cortex using in vivo microdialysis. During resting stage, Ca(2+) output from endoplasmic reticulum Ca(2+) store via inositol-triphosphate receptor regulates syntaxin-associated monoamine exocytosis mechanism, whereas during neuronal hyperexcitable stage, Ca(2+) output via ryanodine receptor regulates synaptobrevin-associated monoamine exocytosis mechanism. Basal monoamine releases were increased and decreased by therapeutically relevant and supratherapeutic concentration of TPM, respectively. The therapeutic-relevant concentration of TPM increased Ca(2+)-evoked release concentration-dependently; however, its stimulatory effect was attenuated in the supratherapeutic range. The K(+)-evoked releases were reduced by TPM concentration-dependently (from therapeutic to supratherapeutic ranges). The therapeutic-relevant concentration of TPM-induced elevation of basal release was reduced by cleavage with syntaxin and inhibition of inositol-triphosphate receptor predominantly, by cleavage with SNAP-25 and synaptobrevin weakly, but not by ryanodine receptor inhibitor. The therapeutic-relevant concentration of TPM-induced elevation of Ca(2+)-evoked release was reduced by cleavage with syntaxin and inositol-triphosphate receptor inhibitor selectively. The therapeutic-relevant concentration of TPM-induced reduction of K(+)-evoked monoamine release was abolished by cleavage with synaptobrevin, but was not affected by cleavage with SNAP-25 or synaptobrevin. The stimulatory effect of ryanodine receptor agonist on K(+)-evoked monoamine release was reduced by TPM, whereas that of inositol-triphosphate receptor agonist was not affected by TPM. Therefore, these results indicate that the combination of the effects of TPM on exocytosis mechanisms associated with SNARE and Ca(2+)-induced Ca(2+)-releasing systems, enhancement of inositol-triphosphate receptor/syntaxin and inhibition of ryanodine receptor/synaptobrevin in pre-frontal cortex, may be involved in clinical actions of TPM.

Animals↗