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T Mihara

Publications and source records attributed to T Mihara.

At least 37 records · Page 2Linked to original sources
PubMed1999

Ictal paraphasia induced by language activity.

Four patients with ictal speech disturbance were studied. Their seizures featured isolated, or series of, brief episodes of fluent paraphasia, paragraphia, and comprehension deficit. These episodes were often induced by language activity. Six patients with ictal paraphasia or paragraphia, as a recurrent habitual seizure, are reported in the literature. All ten cases, including the four cases described here and the six cases reported in the literature, featured patients who uttered meaningless speech fluently or displayed paragraphia. The syllables uttered during seizures contained many neologisms and resembled the neologistic jargon of patients with fluent aphasias of the Wernicke type. Nine patients had clusters or status of brief seizures and four patients had auditory hallucination as an ictal event. The seizures in six patients were easily induced by the use of language. Seizure focus was on the left side in all patients mentioned. The possibility of another type of language-induced seizures than those seen in reading epilepsy or language-induced epilepsy is suggested in which myoclonias of the jaw and face, or upper extremities are the main seizure types.

Adult↗
PubMed1999

Electrical stimulation of the contralateral mesial temporal structure induces an ipsilateral seizure pattern in mesial temporal lobe epilepsy.

PURPOSE: We examined the mode of seizure development induced by electrical stimulation in patients with mesial temporal lobe epilepsy. METHODS: Of 25 patients undergoing intracranial EEG evaluation and electrical stimulation ipsilateral to the presumed site of habitual seizure origin, 17 patients had additional stimulation studies on the contralateral temporal lobe. RESULTS: Fourteen of the 25 patients had seizures induced with ipsilateral stimulation, and two of the 17 patients had seizures with contralateral stimulation. Seizures induced by ipsilateral stimulation started in the ipsilateral temporal lobe, whereas those induced by contralateral stimulation originated from the ipsilateral temporal lobe structure and were identical to the habitual seizures. CONCLUSIONS: Electrical stimulation of the temporal lobe structure opposite the site of habitual seizure origin is said to induce a seizure rarely. However, according to our preliminary results, if contralateral stimulation elicits a habitual seizure in the ipsilateral temporal lobe, it might be considered additional confirmatory evidence of seizure lateralization.

Adult↗
PubMed1999

Competitive adsorption between phospholipid and plasma protein on a phospholipid polymer surface.

The competitive adsorption of proteins and phospholipids on omega-methacryloyloxyalkyl phosphorylcholine (MAPC) polymer was evaluated in this study. Albumin, fibrinogen, and dimyrstoyl phosphatidylcholine (DMPC) were used as model components. The amount of DMPC adsorbed on the MAPC polymers increased with an increase in the MAPC unit composition of the polymer. The methylene chain length of the MAPC unit was another factor influencing the DMPC adsorption when the MAPC unit composition of the MAPC polymer was low. The state of albumin and DMPC liposome adsorbed on the 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer was determined by dynamic contact angle (DCA) measurement. The adsorption strength of albumin on the MPC polymer was weaker than that on the poly[n-butyl methacrylate (BMA)], that is, the albumin was detached from the MPC polymer during the rinsing process. On the poly(BMA) surface, no difference in the shape of the DCA loops before and after contact with the DMPC liposomal suspension was observed. Fibrinogen adsorption on the MAPC polymer was detected by gold-colloid labeled immunoassay. The amount of fibrinogen adsorbed on every MAPC polymer surface was reduced by addition of the DMPC liposome in the fibrinogen solution. The number of platelets adhered on the MAPC polymer was also decreased when the DMPC liposome was present in the fibrinogen solution during pretreatment. We concluded that phospholipids were preferentially adsorbed on the MAPC polymer surface compared with plasma protein and that the adsorbed phospholipids played an important role in showing an excellent blood compatibility on the MAPC polymer.

Adsorption↗
PubMed1998

Why do phospholipid polymers reduce protein adsorption?

The amount of plasma protein adsorbed on a phospholipid polymer having a 2-methacryloyloxyethyl phosphorylcholine (MPC) moiety was reduced compared to the amount of protein adsorbed onto poly[2-hydroxyethyl methacrylate (HEMA)], poly[n-butyl methacrylate (BMA)], and BMA copolymers with acrylamide (AAm) or N-vinyl pyrrolidone (VPy) moieties having a hydrophilic fraction. To clarify the reason for the reduced protein adsorption on the MPC polymer, the water structure in the hydrated polymer was examined with attention to the free water fraction. Hydration of the polymers occurred when they were immersed in water. The differential scanning calorimetric analysis of these hydrated polymers revealed that the free water fractions in the poly(MPC-co-BMA) and poly(MPC-co-n-dodecyl methacrylate) with a 0.30 MPC mole fraction were above 0.70. On the other hand, the free water fractions in the poly(HEMA), poly(AAm-co-BMA), and poly(VPy-co-BMA) were below 0.42. The conformational change in proteins adsorbed on the MPC polymers and poly(HEMA) were determined using ultraviolet and circular dichroism spectroscopic measurements. Proteins adsorbed on poly(HEMA) changed considerably, but those adsorbed on poly(MPC-co-BMA) with a 0.30 MPC mole fraction differed little from the native state. We concluded from these results that fewer proteins are adsorbed and their original conformation is not changed on polymer surfaces that possess a high free water fraction.

Adsorption↗
PubMed1998

Intraspecific variability of the tandem repeats in Nicotiana putrescine N-methyltransferases.

The putrescine N-methyltransferase (PMT) cDNA clone previously isolated from tobacco encodes a spermidine synthase-like protein with an 11 amino acid element repeated four times in tandem at the amino terminus. Genomic Southern blot analyses indicated that this N-terminal repeat array is found in tobacco PMTs but absent in Hyoscyamus and Atropa PMTs. A truncated tobacco PMT in which this repeat array was entirely removed still retained full enzymatic activity when expressed in Escherichia coli. Three PMT genes (NsPMT1, NsPMT2, NsPMT3) isolated from Nicotiana sylvestris encode two, five, and nine tandem repeats, respectively, in the first exon, but otherwise encode highly conserved proteins. Analysis of PCR fragments amplified from the genomes of N. tabacum and its two probable progenitors shows that one of the nine repeat elements in NsPMT3 was precisely deleted in the corresponding N. tabacum gene. These results indicate that direct tandem repeats of a 33 bp sequence that encodes 11 amino acids of no obvious function were added to the ancestral Nicotiana PMT gene, and that the tandem repetition was genetically very unstable, contracting or expanding during evolution of the Nicotiana species.

Amino Acid Sequence↗
PubMed1998

Awareness and responsiveness during partial seizures.

We examined the impairment of consciousness during partial seizures (PS) arising from various brain sites according to the operational definition of the international classification, i.e., altered awareness and/or responsiveness. The subjects were 142 patients who underwent intracranial EEG evaluation and subsequent resective surgery. First, the patients were examined to determine whether they usually had been partially or completely aware of their seizures. Second, spontaneous habitual seizures that had been videotaped with simultaneous intracranial EEG recording were reviewed to determine responsiveness and recall during ictal behavioral alterations. In all, 114 patients were partially or completely aware of their seizures. Patients who tended not to be aware of their seizures were those with frontal lobe epilepsy (FLE) with extensive epileptogenic regions on the language nondominant side and those with temporal lobe epilepsy (TLE) with seizure origin in the lateral cortex of the language dominant side. Of the 21 patients with FLE, 88 with TLE, and 4 with occipital lobe epilepsy, 7, 22, and 2 patients responded to stimuli during the seizure, respectively, but only 11 of the patients with FLE and none of the other patients could recall the stimuli applied during the behavioral alterations. Bilateralization of seizure discharges correlated with impaired responsiveness. According to the International Classification, about half of patients with FLE had only simple partial seizures (SPS) and the other patients had complex partial seizures (CPS). Altered awareness and/or responsiveness occurred in most habitual partial seizures in our subjects. The term "complex" appears to be useful in clinical practice, although the contents of ictal behavior and the site or side of seizure origin are not implied.

Adolescent↗
PubMed1997

[Focal cortical dysplasia and epilepsy surgery].

We conducted corticectomy in twenty-five patients with intractable partial epilepsy due to focal cortical dysplasia (FCD). MRI could not detect FCDs in three patients, interictal SPECT, however, revealed hypoperfusion corresponding to FCDs in two of these patients, while the FCD in one remaining patient was histologically identified in a resected specimen. The location of FCDs was as follows: the frontal lobe in sixteen patients, the temporal in five, the occipital in two, fronto-parietal in one, and the temporo-parietal in one. Prior to the surgery, twenty-one patients underwent invasive long-term intracranial EEG/CCTV monitoring. Of the fourteen patients who were tracked for longer than 2 years following surgery, eleven belonged to Class I according to Engel's criteria, two to Class II, and one to Class III. We compared intracranial EEG findings (interictal and ictal) between these twenty-one patients and eight patients with frontal lobe epilepsy resulting from different lesions. The results of this comparison, together with the seizure outcome following surgery, indicated that FCD is intrinsically epileptogenic. The invasive long-term monitoring should, as a rule, be performed in all patients with FCDs prior to the corticectomy.

Adolescent↗
PubMed1997

Effect of Apafant on bronchial hyperresponsiveness and down-regulation of beta-adrenoceptors induced by endotoxin in guinea pigs.

Intraperitoneal injection of endotoxin resulted in bronchial hyperreactivity to histamine in guinea pigs. In addition, endotoxin (lipopolysaccharide, LPS) caused a decrease in the relaxation of the lung parenchymal strips induced by the beta-adrenoceptor agonist, isoproterenol (isoprenaline), and a reduction in the number of beta-adrenergic binding sites in the lung membrane preparation in guinea pigs. Apafant (CAS 105219-56-5, WEB 2086) was effective in the prevention of endotoxin-induced changes, i.e., bronchial hyperreactivity to histamine, a decrease in the relaxation of lung parenchymal strips induced by isoproterenol and a reduction in the number of beta-adrenergic binding sites in the lung membrane preparation in guinea pigs. Ketotifen and ozagrel also prevented the bronchial hyperresponsiveness and endotoxin-induced deterioration of the beta-adrenergic system. No remarkable effect was observed with cromolyn sodium and salbutamol in the bronchial hyperreactivity to histamine induced by endotoxin in guinea pigs. Cromolyn sodium also caused no influence on the down-regulation of beta-adrenoceptors.

Adrenergic beta-Agonists↗
PubMed1996

Recommendation of early surgery from the viewpoint of daily quality of life.

We surveyed pre- and postoperative levels of satisfaction with a range of the daily quality-of-life (QOL) domains in 132 sets of epilepsy surgery patients and their families. All patients underwent resective surgery for temporal lobe epilepsy and were monitored for > 2 years. Patient and family assessments showed patients' overall QOL markedly improves after surgery, depending on freedom from seizures. However, factors such as social contacts, family relations, or financial status improved little. Some families and patients were not satisfied with the postsurgical status, despite freedom from seizures. Patients who had surgery at a later age were not so satisfied with their postsurgical status as were patients who had surgery at a younger age, particularly on the QOL domains of role activities, memory function, leisure activities, or emotional well-being. This lower satisfaction level in older patients likely results from a variety of problems affecting patients during the long-lasting epileptic process; social handicaps, psychologic conflicts, and deterioration of cognitive/behavioral functions. Based on each case, we recommend that investigations start at an early stage of the illness, so that surgical intervention may be considered as early as possible.

Activities of Daily Living↗
PubMed1996

Mechanism of Bradykinin-induced histamine release from rat peritoneal mast cells.

Bradykinin at concentrations higher than 2 microM caused a significant histamine release from rat peritoneal mast cells when extracellular Ca2+ was removed from the medium. Under the same experimental conditions, bradykinin increased Ca2+ release from the intracellular Ca store of the rat peritoneal mast cells, and a clear relationship was observed between the magnitude of histamine release and an increase in fluorescence intensity. Addition of Ca2+ to the medium resulted in an inhibition of the response to bradykinin in a concentration-dependent manner. Almost the same results were obtained when Mg2+, Ba2+ and La3+ were added to the medium. Neither B1 nor B2 antagonists caused significant antagonistic effects on histamine release induced by bradykinin. However, B2 antagonists caused a histamine release of the same potency as bradykinin when applied alone. These results indicate that bradykinin-induced histamine release is not attributable to a bradykinin receptor.

Animals↗
PubMed1995

Holmium: yttrium-aluminum-garnet laser for endoscopic lithotripsy.

OBJECTIVES: To evaluate the holmium:yttrium-aluminum-garnet (Ho:YAG) laser for endoscopic lithotripsy on patients diagnosed with urinary tract calculi. METHODS: Thirty-eight procedures utilizing transurethral ureterolithotripsy or percutaneous nephroureteral lithotripsy were evaluated: 5 renal calculi, 31 ureteral calculi (most in the upper ureter), 1 ureteropelvic junction calculus, and 1 bladder calculus. These were mainly in cases that, after being treated with extracorporeal shock-wave lithotripsy (ESWL), were contraindicated for further ESWL. Laser parameters included energy of 0.5 to 1.0 J/pulse and pulse rate of 5 to 10 Hz. RESULTS: Composition of calculi was determined in 26 procedures. The Ho:YAG laser was effective for fragmenting all types of calculi. Patient outcome evaluated at 6 weeks after treatment showed that 33 of 38 procedures (87%) were effective. Residual calculi in 4 of the 5 unsuccessful procedures were less than 5 mm in size and judged to be able to pass spontaneously. In the remaining procedure, the calculus was passed spontaneously 3 months after treatment. No severe damage to tissues or adverse effects to the body were observed due to the Ho:YAG laser. CONCLUSIONS: On the basis of these results, we determine that this wavelength is effective for lithotripsy in addition to its previously reported usefulness for soft tissue applications, and, thus, is a cost-effective and highly useful clinical device.

Adult↗
PubMed1995

Distribution of genes encoding cholera toxin, zonula occludens toxin, accessory cholera toxin, and El Tor hemolysin in Vibrio cholerae of diverse origins.

A large collection of 1154 strains of Vibrio cholerae of diverse origins including serogroups 01 and 0139 and those belonging to the non-01 and non-0139 (non-01:non-0139) serogroups were examined with a battery of DNA probes specific for cholera toxin (CT), zonula occludens toxin (ZOT), accessory cholera toxin (ACE) and El Tor hemolysin (HLY) to determine the distribution of genes among wild strains and to understand the importance of these factors in the pathogenesis of the disease cholera. Among the 01 clinical isolates, the majority of the strains had an intact core region (ctx, zot, ace) and also possessed the hlyA gene. Although rare, strains of 01 with natural deletions of the ctx, zot and/or ace genes were also detected. The absence of the virulence genes comprising the core region and the presence of the hlyA gene dominated the 01 environment, food isolates and the clinical and environmental non-01: non-0139 strains of V. cholerae. All the 0139 strains examined in this study possessed genes located in the core region and the hlyA gene. Among all the virulence-associated genes examined, the hlyA gene was the most conserved genetic element in V. cholerae independent of biotypes and serogroups.

Bacterial Proteins↗
PubMed1995

[Beneficial effects of the combination of idebenone and manidipine 2HCl on neurological deficits and histological changes following cerebrovascular lesions in stroke-prone spontaneously hypertensive rats].

We investigated the effects of the combination of idebenone, an energy metabolism enhancer, and manidipine 2HCl, a dihydropyridine-derivative calcium antagonist, on neurological deficits and histological changes in the brain and kidneys of stroke-prone spontaneously hypertensive rats (SHRSP) with cerebrovascular lesions (stroke). The SHRSP were kept on a 1% NaCl solution as their drinking water to synchronize the onset of stroke. After the onset of stroke symptoms, the salt solution was replaced with tap water. On the day following the onset of stroke, idebenone (50 mg/kg), manidipine 2HCl (2 mg/kg) or a combination of idebenone (50 mg/kg) and manidipine 2HCl (2 mg/kg) was administered orally once a day for 3 weeks. In the combination group and manidipine 2HCl-treated group, the neurological deficits after the onset of stroke were ameliorated during the entire experimentalperiod. Especially, the combination significantly decreased the number of days with severe neurological deficits as compared to the control group. The combination and manidipine 2HCl significantly recovered the decrease in body weight and ameliorated the increase of brain weight, which was mainly caused by edema, significantly as compared to the control group. Manidipine 2HCl ameliorated the histological changes in the brain. In the combination group, the histological changes in both the brain and the kidneys were ameliorated. In conclusion, the combination of idebenone and manidipine 2HCl significantly ameliorated the neurological deficits and the histological changes in the brain and the kidney of SHRSP with stroke as compared to each individual treatment. We concluded that manidipine 2HCl enhances the therapeutic effect of idebenone in the treatment of cerebrovascular diseases.

Administration, Oral↗
PubMed1994

Improvement of quality-of-life following resective surgery for temporal lobe epilepsy: results of patient and family assessments.

In order to evaluate the quality-of-life (QOL) of epilepsy surgery patients, we surveyed patients' degree of life satisfaction and their families' degree of satisfaction with patient's status in a range of domains both pre- and post-operatively. Of 100 patient-family sets of surveys that were mailed out, 93 were completed and returned from patients and 91 from their families. All patients surveyed had temporal lobe epilepsy and had been followed for longer than 2 years after resective surgery. Patients and their families rated overall QOL as having markedly improved following surgery. However, they rated social domains of QOL, including role activities, financial status, and social and family relationships as having improved relatively little. Despite freedom from seizures, a few patients' families were dissatisfied with the patients' post-operative status, primarily for psychosocial reasons. Patients operated on at a later age reported little gains in life satisfaction following surgery. This study supports the conclusion that surgical intervention should occur before patients are subjected to the psychological conflicts and social handicaps associated with chronic intractable epilepsy.

Adaptation, Psychological↗
PubMed1994

Characterization of phenotypic, serological, and toxigenic traits of Vibrio cholerae O139 bengal.

Biochemical and physiological traits of a collection of strains of Vibrio cholerae O139 Bengal isolated from India, Bangladesh, and Thailand showed that these strains formed a phenotypically homogeneous group with identical characteristics that were essentially similar to those of the O1 serogroup. Resistance to 150 micrograms of the vibriostatic agent O/129 (2,4-diamino-6,7-diisopropylpteridine) and Mukherjee's El Tor phage 5 and classical phage IV and the nonagglutinability of the strains with O1 antiserum were the only discernible differences between the O139 and O1 serogroups. Extensive serological characterization further revealed the O139 serogroup to be distinct from the existing 138 serogroups of V. cholerae. Antiserum raised against the O139 serogroup required absorption with the R reference strain CA385 and with the reference strain representing serogroup O22 to remove cross-reacting agglutinins. All of the 223 representative strains of V. cholerae O139 examined hybridized with DNA probes specific for the cholera toxin (CT) gene, zonula occludens toxin gene, and El Tor hemolysin gene but not with the probe specific for the heat-stable enterotoxin gene. The amount of CT present in stool samples of patients infected with the O139 serogroup was higher than that found in stools of patients infected with O1 El Tor, and this echoed findings that the amount of CT produced by O139 strains in vitro was higher than that produced by the O1 El Tor strains. The nucleotide sequences of the genes encoding the A and B subunits of CT of the O139 serogroup were identical to the sequences reported for the CT gene of O1 El Tor. The CT gene of O139 strains could be amplified by using primers developed for detection of the CT gene of the O1 serogroup by a PCR assay, which could also be used to detect the CT gene in stool samples of patients infected with strains of the O139 serogroup.

Animals↗
PubMed1993

Distribution of the zot (zonula occludens toxin) gene among strains of Vibrio cholerae 01 and non-01.

The distribution of the zot gene that encodes the zonula occludens toxin, a newly described toxin of Vibrio cholerae, among clinical, environmental and food isolates of V. cholerae 01 and non-01 was investigated. Both the zot gene and the ctx gene that encode cholera toxin were found in 247 of 257 clinical strains and 62 of 415 environmental or food isolates of V. cholerae 01. The zot gene, but not the ctx gene was found in 37 strains (one clinical strain and 36 environmental or food isolates). In addition, two of 31 clinical strains and six of 98 environmental or food isolates of V. cholerae' non-01 possessed both the zot gene and the ctx gene. These results demonstrated the predominantly concurrent occurrence of the zot gene and ctx genes among strains of V. cholerae 01 which suggests a possible synergistic role of ZOT in the causation of acute dehydrating diarrhea produced by V. cholerae 01.

Cholera Toxin↗
PubMed1993

Localizing value of seizure manifestations of temporal lobe epilepsies and the consequence of analyzing their sequential appearance.

We investigated the localizing and lateralizing value of principal seizure manifestations in temporal lobe epilepsies (signal symptoms, oroalimentary automatisms, somatomotor manifestations, unilateral dystonic posturing, ictal speech, motionless stare) of 223 complex partial seizures in 50 patients. All the patients had invasive long-term monitoring with the combined implantation of intracerebral electrodes in and subdural electrodes on the bilateral temporal lobes. Postoperative freedom from seizures was ascertained for longer than one year. We found that 35 patients had amygdalohippocampal seizures and 15 had lateral temporal seizures. The value of the manifestations was established in relation to the site and side of seizure origin and to the progression of seizure discharges within the unilateral temporal lobe or to the contralateral cerebral hemisphere. Several signs among the manifestations were found to be reliable in predicting the site or side of the temporal lobe seizure focus. We emphasized the importance of investigating sequential changes of seizure manifestations in relation to ictal EEG findings by means of simultaneous recording.

Amygdala↗