Biomedical subjects

Masahiro Morita

Publications and source records attributed to Masahiro Morita.

11 recordsLinked to original sources

PubMed2005

Evaluation of some halogen biocides using a microbial biofilm system.

A simple method for the formation of microbial biofilms of three species, Pseudomonas fluorescens, Pseudomonas aeruginosa, and Klebsiella pneumoniae, on a small glass slide was established, and its suitability for evaluation of disinfectant efficacy was examined. The biofilms formed were observed in situ by confocal laser scanning microscopy (CLSM). Using the biofilms established, biocidal efficacy of several halogen biocides, such as hypochlorite (HOCl), bromochlorodimethylhydantoin (Br, Cl-DMH), ammonia monochloramine (NH2Cl), a stabilized hypobromite biocide named STABREX, and a mixed solution of NH4Br and HOCl, was evaluated. The formation of NHBrCl in the mixed solution was indicated by UV spectra analysis. Biofilm cells were more resistant to these biocides than planktonic cells and the extent of resistance varied with the biocide tested. Among the biocides tested, the biocidal potency of HOCl was the most susceptible to the change brought about by biofilm formation. By CLSM observation, differences in biofilm conformation were revealed between the microbial species. The efficacy of the biocide tested varied with the structure of biofilms formed. The assay method developed in the present study would be useful for further investigation on biofilm disinfection.

Anti-Bacterial Agents↗

PubMed2004

Risk factors for adjacent segment degeneration after PLIF.

STUDY DESIGN: A retrospective study of 87 patients who underwent posterior lumbar interbody fusion (PLIF) at L4-L5 for L4 degenerative spondylolisthesis. OBJECTIVE: To clarify: 1) the correlation between radiologic degeneration of cranial adjacent segment and clinical results, 2) risk factors for radiologic degeneration of cranial adjacent segment, and 3) preoperative radiologic features of patients who underwent additional surgery with cranial adjacent segment degeneration. SUMMARY OF BACKGROUND DATA: Whereas PLIF with pedicle screw fixation has shown satisfactory clinical results, a solid fusion has been reported to accelerate a degenerative change at unfused adjacent levels, especially in the cranial level. Although several authors have reported the adjacent segment degeneration after PLIF, there are no previous reports of risk factors for adjacent segment degeneration after PLIF. MATERIALS AND METHODS: Eighty-seven patients who underwent PLIF for L4 degenerative spondylolisthesis and could be followed for at least 2 years were included in this study. We measured lumbar lordosis, scoliosis, laminar inclination angle at L3, facet sagittalization at L3-L4, facet tropism at L3-L4, preexisting disc degeneration at L3-L4, and lordosis at the fused segment. Progression of L3-L4 segment degeneration was defined as a condition in which disc narrowing, posterior opening, and progress of slippage in comparison with preoperative dynamic lateral radiographs. Patients were divided into three groups according to postoperative progression of L3-L4 degeneration: Group 1 with neither progression of L3-L4 degeneration nor neurologic deterioration, Group 2 with progression of L3-L4 degeneration but no neurologic deterioration, and Group 3 with an additional surgery required for neurologic deterioration. Correlation between clinical results and radiologic progression of L3-L4 degeneration, and risk factors for progression of radiologic degeneration were investigated. Further, preoperative radiologic features of Group 3 were studied to detect risk factors for clinical deterioration. RESULTS: There were 58 (67%) patients classified into Group 1, 25 (29%) patients into Group 2, and 4 (4%) patients into Group 3. There was no significant difference in average age in each group. No obvious difference was observed in recovery rate between Groups 1 and 2. Laminar inclination angle and facet tropism in Group 3 were more significant than those in Groups 1 and 2. Further, apparent lamina inclination and facet tropism coexisted in Group 3. There were no obvious differences in other factors between each group. CONCLUSION: 1) There was no correlation between radiologic degeneration of cranial adjacent segment and clinical results. 2) Risk factors for postoperative radiologic degeneration could not be detected in terms of each preoperative radiologic factor. 3) Coexistence of horizontalization of the lamina at L3 and facet tropism at L3-L4 may be one of the risk factors for neurologic deterioration resulting from accelerated L3-L4 degenerative change after L4-L5 PLIF.

Adult↗

PubMed2004

SCA17 homozygote showing Huntington's disease-like phenotype.

We report a homozygous case of spinocerebellar ataxia type 17 with 48 glutamines. The age of the patient at disease onset was not lower than those of heterozygotes with the same CAG-repeat sizes, but the clinical manifestations were rapidly progressive dementia and chorea. Neuronal loss was relatively restricted and most prominent in the Purkinje cell layer and striatum; however, intranuclear neuronal polyglutamine accumulation was widespread, with a high frequency in the cerebral cortex and striatum.

Adult↗

PubMed2004

Vertical canal function in normal subjects and patients with benign paroxysmal positional vertigo.

OBJECTIVES: To assess the dynamics of the vertical semicircular canal (VSCC)-ocular reflex in normal subjects and then to compare their gain in VSCC-ocular reflex with that of patients with benign paroxysmal positional vertigo (BPPV). MATERIAL AND METHODS: Subjects were sinusoidally rotated around the earth-vertical axis with their head tilted 60 degrees backward and turned 45 degrees to the right or left side from the sagittal plane at frequencies of 0.1, 0.3, 0.5, 0.7 and 1.0 Hz with a maximum angular velocity of 50 degrees/s. Head rotation to the right side on the right anterior semicircular canal (SCC)-left posterior SCC plane or to the left side on the left anterior SCC-right posterior SCC plane stimulated the pair of VSCCs. Eye movements were recorded on a video imaging system with an infrared charge-coupled device camera, using our new technique for analyzing the rotation vector of eye movements in three dimensions. RESULTS: The mean gains in left posterior SCC-ocular reflex in normal subjects ranged from 0.44 at 0.1 Hz to 0.79 at 1.0 Hz, while the mean gains in right anterior SCC-ocular reflex ranged from 0.45 at 0.1 Hz to 0.73 at 1.0 Hz. The mean gains in right posterior SCC-ocular reflex in normal subjects ranged from 0.53 at 0.1 Hz to 0.89 at 1.0 Hz, while the mean gains in left anterior SCC-ocular reflex ranged from 0.53 at 0.1 Hz to 0.88 at 1.0 Hz. Thus, the gains in VSCC-ocular reflex did not differ among the four VSCCs in normal subjects. Similarly, vestibulo-ocular reflex (VOR) gains of the four VSCCs in patients with right- or left-sided BPPV were almost the same at all frequencies compared to those of normal subjects. CONCLUSION: In patients with BPPV, gains in VOR in the four VSCCs were not changed in comparison with those of normal subjects. It is suggested that the mass of free-floating otoconial debris associated with canalolithiasis was too small compared to that of the endolymph to change the canal dynamics.

Adult↗

PubMed2004

[Advanced gastric cancer successfully treated by TS-1--case report].

A 73-year-old woman came to our hospital because of poor appetite, and careful examination revealed a Borrmann type 2 tumor on the posterior wall of the lower body of the stomach as well as enlarged para aortic-lymph nodes. Surgery was performed in November 2000, but because the para-aortic lymph nodes were densely adherent to the aorta, it was impossible to dissect the lymph nodes from the wall (N3, Stage IV). Postoperatively, a course of TS-1 100 mg/day for 4 weeks and discontinuation for 2 weeks was started. After one course of TS-1, the enlarged para-aortic lymph nodes were no longer seen on abdominal computed tomography (CT). The dose of TS-1 was subsequently reduced to 80 mg/day because of adverse effects. Although the patient is still taking TS-1, she is well with no signs of recurrence 34 months after surgery.

Adenocarcinoma↗

PubMed2003

Pathological involvement of the motor neuron system and hippocampal formation in motor neuron disease-inclusion dementia.

We report two patients with motor neuron disease-inclusion dementia, with special reference to the pathology of the motor neuron system and hippocampal formation. The ages of the patients at death were 55 and 62 years, and the disease durations were 8 and 3 years, respectively. The two patients exhibited progressive frontotemporal dementia in the absence of motor neuron signs. At autopsy, both cases exhibited frontotemporal lobar atrophy with ubiquitin-positive, and tau- and alpha-synuclein-negative neuronal inclusions. As expected from the clinical signs, in both cases, the upper and lower motor neuron systems were well preserved: no Bunina bodies or ubiquitinated inclusions were detected in the motor neurons. However, of great importance was that when visualized immunohistochemically, the Golgi apparatus and trans-Golgi network often exhibited fragmentation in the lower motor neurons (the spinal anterior horn cells). In one of the cases, a decrease in the amount of Golgi apparatus was also a frequent feature in the upper motor neurons (Betz cells in the motor cortex). Moreover, in both cases, circumscribed degeneration affecting the CA1-subiculum border zone was evident in the hippocampal formation. These findings further strengthen the idea that, pathologically, motor neuron disease-inclusion dementia is a rare phenotype of amyotrophic lateral sclerosis.

Crystallins↗

PubMed2003

A new rotational test for vertical semicircular canal function.

OBJECTIVE: We developed a new rotating chair in order to assess the function of the vertical semicircular canal (VSCC) by analyzing VSCC-induced post-rotatory nystagmus (PRN). METHODS: We examined 14 healthy subjects, wearing goggles equipped with an infrared CCD camera, and sitting on a chair which was designed to stimulate a pair of the VSCCs by tilting the head 60 degrees backward with a 45 degrees rotation to the left or right side from the sagital plane. The time constant (TC) or maximal slow phase eye velocity (MSPEV) of the vertical component of four kinds of PRN were analyzed in four corresponding rotatory conditions, and used as functional index of the corresponding VSCC. RESULTS: The mean values of MSPEV in both anterior semicircular canal (ASCC) and posterior semicircular canal (PSCC)-induced PRN tended to be lower (P<0.10) than those induced by the lateral semicircular canal (LSCC). The result suggests that the threshold to the angular velocity in the VSCC is lower than that in the LSCC. The mean values of TC in both ASCC and PSCC-induced PRN were significantly lower (P<0.05) than those induced by the LSCC. CONCLUSION: The significant reduction of TC in VSCC-induced PRN compared with LSCC-induced PRN indicates that VSCC function is less affected by velocity storage mechanisms than LSCC function. The rotational test with respect to the VSCC can be used as a tool for assessing vertical canal function.

Adult↗

PubMed2003

[Factors related to discrepancy in evaluation on functional capacity between reports by community-dwelling older people with cognitive decline and their family members].

Overestimation or underestimation of functional capacity in community-dwelling older people with cognitive impairment was evaluated between the responses of subjects and family members (proxies) by cognitive function level. Out of all the residents aged 65 years and over living in Yoita town, Niigata Prefecture in 2000 (n = 1,673), 1,544 voluntarily participated in the interview survey held at community halls or at home (92.3% response). They underwent the Mini-Mental State Examination (MMSE) for assessment of cognitive function and answered questionnaires comprising socio-demographic, psychological, physical and medical, and social activity items (2000/11). According to the age of the subject and MMSE score, we defined cognitive decline (MMSE scores < 1 SD below age-specific means, n = 371). 158 pairs among 371 subjects with cognitive decline and their proxies participated in a follow-up survey (2001/11). The subjects themselves underwent MMSE again. 136 subject-proxy pairs reported any complaints of memory-related problem and evaluated higher-level functional capacity (TMIG-IC, Tokyo Metropolitan Institute of Gerontology Index of Competence). We established criteria at follow-up survey as follows: control (n = 29), MMSE scores > 1 SD below age-specific means and CDR (Clinical Dementia Rating) = 0: mild cognitive decline (MCD) (n = 54), 21 < or = MMSE scores < 1 SD below age-specific means or CDR = 0.5); and severe cognitive decline (SCD) (n = 53), MMSE scores 20 < or = CDR > 0.5. SCD subjects significantly overestimated total and Instrumental Self-Maintenance scores in TMIG-IC more than control or SCD subjects. Multiple logistic regression analyses indicated that complaints of memory by the proxy, response by spouse, and higher levels of education were extracted as significantly independent variables affecting overestimation for functional capacity. On the other hand, aging affected underestimation.

Activities of Daily Living↗

PubMed2003

[Test-retest variation in the Tokyo Metropolitan Institute of Gerontology Index of Competence in community-dwelling older people independent in daily living toward individual assessment of functional capacity].

OBJECTIVES: To assess individual variation in the functional capacity of community-dwelling older people who are almost independent in daily living, using the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-Index of Competence). METHODS: Out of 74 elderly outpatients showing a total score of TMIG-Index of Competence above 10 points at baseline, 61 who remained stable during subsequent two months in terms of medical and social aspects were assessed for their functional capacity with the test-retest method using the TMIG-Index of Competence. We assessed individual variation between the tests of one month interval with correspondence rate. RESULTS: The ranges for score differences within which correspondence rates of 95% and over applied were as follows: within 1 point for the total score of the Index (95.1%), 0 point in the Instrumental Self-Maintenance subscale (IADL) (95.1%), and 1 point in the Intellectual Activity subscale (Intellectual Activity) (98.4%) and the Social Role subscale (Social Role) (98.3%). CONCLUSIONS: The variation of 1 point for the total score of the Index, and subscales of Intellectual Activity and Social Role was regarded as a possible measurement error. In other words, variations of 2 points and over for total score, subscales of Intellectual Activity and Social Role, and variations of 1 point and over for IADL should not be ignored in screening of functional capacity among older people.

Activities of Daily Living↗

PubMed2003

[Toward constructing a system for detecting and coping with senile dementia in early stages among community-dwelling older people].

OBJECTIVES: To establish a community health care system for screening community-dwelling older people with mild cognitive decline (MCD) and early diagnosis by a medical specialist. METHODS: Out of all the elderly residents aged 65 years and over living in Yoita town in 2000 (n = 1673), 1544 participated in the interview survey held at community halls or at home (92.3% response). They underwent a Mini-Mental State Examination (MMSE) for assessment of cognitive function and answered questionnaires covering socio-demographic, psychological, physical and medical, and social activity items (2000/11). We defined cognitive decline as an MMSE < or = 1 SD below the age-specific mean (n = 371). Out of a total eligible population of 332, 158 pairs of subjects and their proxies participated in a follow-up survey (2001/11). The subjects themselves underwent MMSE again, and were asked for complaints of memory-related problems. Proxies answered about functional capacity and memory-related problems of subjects, for which we assessed the level of dementia with the Clinical Dementia Rating (CDR). We established criteria for encouragement to undergo detailed examination by a medical specialist as follows. 1) MMSE scores < or = 1 SD below age-specific means at both baseline and follow-up surveys, or 2) CDR > or = 0.5, and 3) not due to mental retardation. RESULTS: Non-participants had significant higher MMSE scores but were younger in the follow-up survey. Out of 96 subjects eligible for the detailed examination, 47 participants showed a tendency for older age with lower MMSE scores or younger age with higher MMSE scores than the average in the follow-up survey. The detailed examinations confirmed dementia of Alzheimer's type in 22 and vascular dementia in 13 on DSM-IV or magnetic resonance imaging. During our screening, 8 community care saloons were opened and the number of facilities for older people with cognitive decline is increasing. CONCLUSIONS: To establish a community health care system to screen and cope with community-dwelling older people with MCD in earlier stages, increased awareness of residents with slight MCD is especially important. Our attempt also suggested the importance of educational lectures, methods for testing cognitive function, and dementia care activity.

Aged↗

PubMedDate not supplied

Three-dimensional eye rotation axis analysis of benign paroxysmal positioning nystagmus.

We have developed a new technique for analyzing the rotation vector of eye movement with an infrared CCD camera [Imai et al.: Acta Otolaryngol 1999;119:24-28]. We used this technique to analyze the eye rotation axis of benign paroxysmal positioning nystagmus (BPPN) that was induced by the Dix-Hallpike maneuver in 14 patients with benign paroxysmal positioning vertigo (BPPV). Eye rotation axes of BPPN in 8 patients were closely perpendicular to the posterior canal of the undermost ear in the provocative head position. Under the hypothesis that BPPN is due to a mechanical stimulation of the posterior canal by canalolithiasis, this finding suggested that the posterior canal of the undermost ear is the lesion. On the other hand, eye rotation axes of BPPN in the other 6 patients were closely aligned with the naso-occipital axis. It is suggested that canalolithiasis induces endolymphatic flow in both posterior and anterior canals via the common crus and the summation of the eye movements induced by stimulation of both the posterior and anterior canals rotates the eye along the naso-occipital axis.

Adult↗