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T Yonehara

Publications and source records attributed to T Yonehara.

At least 19 recordsLinked to original sources
PubMed2006

Intermittent oro-esophageal tube feeding in acute stroke patients -- a pilot study.

OBJECTIVE: Acute stroke patients with dysphagia are usually fed by nasogastric tube. However, this method sometimes causes pneumonia or diarrhea. We investigated the use of a new feeding procedure called intermittent oro-esophageal (IOE) tube feeding in acute stroke patients with severe dysphagia. MATERIALS AND METHODS: The IOE method was used in 13 acute stroke patients (68 +/- 14 years old; 12 had a brainstem infarction), who were alert, but had severe dysphagia and a weak pharyngeal reflex. IOE tube feeding was carried out as follows. A feeding tube was passed orally into the lower portion of the esophagus, food supplements were administered through the tube at a rate of approximately 50 ml/min, and the tube was removed after finishing the supplement infusion. RESULTS: We found that the IOE method had the following advantages: (i) IOE feeding took approximately 15 min; (ii) potentially reduced a risk of complications such as pneumonia and diarrhea; and (iii) oral tube insertion stimulated the oral cavity and pharynx, which may improve the swallowing function. However, the IOE feeding method should not be used in patients who: (i) could not understand the IOE procedure; (ii) had an esophageal hiatal hernia or incomplete peristalsis of the esophagus, as such patients are at risk of having the supplement reflux into the oral cavity. CONCLUSION: The IOE feeding method may be one of the alternatives to continuous nasogastric tube feeding in acute stroke patients with severe dysphagia, who are alert.

Acute Disease↗
PubMed2004

DWI abnormalities and clinical characteristics in TIA patients.

OBJECTIVE: To determine the clinical characteristics of diffusion-weighted images (DWIs) in patients with TIA. METHODS: The authors performed prospectively MRI including DWI in 129 consecutively studied patients with TIA (mean age, 67 years; 68% men) within 14 days after TIA onset. They examined the frequency of TIA-related DWI abnormalities and compared the clinical background of patients with and without DWI abnormalities. Using multivariate statistical methods, the authors investigated the independent factors associated with detection of DWI abnormalities. RESULTS: Fifty-seven patients with TIA (44%) had DWI abnormalities (positive group), whereas 72 (56%) had no abnormalities (negative group). Prolonged TIA duration (TIA duration > or = 30 minutes), hemiparesis, monoparesis, disturbance of higher brain function, history of either stroke or TIA, diabetes mellitus, and atrial fibrillation were observed more frequently in the positive group than in the negative group. No difference in other symptoms, vascular risk factors, or emboligenic cardiac and arterial disease was observed between the two groups. A multiple logistic regression model demonstrated that prolonged TIA duration (odds ratio [OR], 3.7; 95% CI, 1.3 to 10.8) and disturbance of higher brain function (OR, 10.2; 95% CI, 2.2 to 46.9) are significant and independent factors in correlating with DWI abnormalities. CONCLUSIONS: TIA-related DWI abnormalities are associated with prolonged duration of TIA and disturbance of higher brain function. More sustained and extensive ischemia may contribute to DWI abnormalities in patients with TIA.

Aged↗
PubMed2001

Involvement of mitogen-activated protein kinase in cyclic adenosine 3',5'-monophosphate-induced hormone gene expression in rat pituitary GH(3) cells.

We examined whether mitogen-activated protein (MAP) kinase was activated by stimulation of the cAMP pathway and whether MAP kinase activation was involved in synthesis of PRL and GH in GH(3) cells. Treatment of the cells with a cAMP analog, 8-(4-chlorophenylthio)cAMP (CPT-cAMP), activated MAP kinase and increased PRL at both the protein and messenger RNA levels. The protein and messenger RNA of GH were decreased by the treatment. We constructed the luciferase reporter genes after the promoters of PRL and GH and found the activation of both promoters by the CPT-cAMP treatment. We confirmed that overexpression of the catalytic subunit of cAMP-dependent protein kinase had essentially the same effects on MAP kinase activation and synthesis of PRL and GH as the CPT-cAMP treatment. Furthermore, treatment of the cells with pituitary adenylate cyclase-activating polypeptide 27 activated MAP kinase. The activation of PRL promoter by CPT-cAMP and pituitary adenylate cyclase-activating polypeptide 27 was abolished by pretreatment with PD098059 and H89. Although the increase in PRL and GH secretion by CPT-cAMP was inhibited by H89, PD098059 had no effect on secretion. These results suggest that cAMP-induced MAP kinase activation is essential for PRL gene expression, but not for secretion of PRL and GH.

Animals↗
PubMed2001

Susac's syndrome: beneficial effects of corticosteroid therapy in a Japanese case.

Susac's syndrome is a rare disorder characterized by the triad of microangiopathy of the brain and retina with hearing loss. More than 50 affected individuals have been reported worldwide, all Caucasians. We herein identify the first Japanese patient with Susac's syndrome. A 36-year-old man developed recurrent subacute encephalopathy, bi- a lateral sensorineural hearing loss, and retinal arteriolar occlusions, caused by microangiopathy from a year previously. T2-weighted MRI showed multiple high-signal lesions ti predominantly in the periventricular white matter. During the exacerbated phase both high-dose intravenous methyl-prednisolone and oral prednisone therapy produced beneficial effects. He showed definite remission within 2 years from the disease onset.

Adult↗
PubMed2001

Familial multiple trichoepithelioma associated with subclavian-pulmonary collateral vessels and cerebral aneurysm--case report.

A 63-year-old woman presented with cerebellar infarction caused by occlusion of the right posterior inferior cerebellar artery. She had papules on her face that were identified histologically as multiple trichoepithelioma. Angiography revealed right subclavian-pulmonary collateral vessels and a cerebral aneurysm arising from the bifurcation of the right middle cerebral artery. Her grandmother, mother, and uncle had had similar papules, and the deaths of her mother and uncle were due to subarachnoid hemorrhage.

Aged↗
PubMed2001

[Evaluation of time dependency of the acetazolamide effect on cerebral hemodynamics as measured by 99mTc-ECD single-photon emission computed tomography].

PURPOSE: Kuwabara et al. have examined the cerebral artery dilation with acetazolamide (ACZ) challenge test using PET. And, they reported that ACZ reaction came out time dependently. We have developed a unique SPECT's method using Technetium-99m ethyl cysteinate dimer (99mTc-ECD) to verify the results obtained by Kuwabara et al. METHOD: 1000 MBq of 99mTc-ECD was exactly divided into three syringes. Each of which was intravenous infused (i.v.) at rest, 7.5, and 20 minutes after ACZ administration. Data collection was started using dynamic SPECT immediately after 99mTc-ECD i.v. at rest. Using necessary data only, SPECT images representing each of the three 99mTc-ECD i.v. was reconstructed. SPECT counts were obtained by the ROI method from each images to calculate relative CBF from rest to 7.5 and 20 minutes after ACZ administration. RESULT: The 18 hemispheres of nine patients in the negative control group in whom ACZ was not loaded. CBF was stable during the three evaluation. The measurement error our method was estimated as small. The 18 hemispheres of nine patients in the positive control group who has normal vasodilatory reserve, CBF was increased by 26.2 +/- 8.1% at 7.5 minutes and 29.3 +/- 13.1% at 20 minutes after ACZ administration. Seven patients with and chronic stage unilateral internal carotid artery severe stenosis and/or occlusion were evaluated as the test group. Case of unaffected side, CBF was increased by 17.6 +/- 6.9% at 7.5 minutes and 24.8 +/- 11.3% 20 minutes after ACZ administration. And, increase rate of CBF in the affected side was 2.8 +/- 1.6% at 7.5 minutes and 17.3 +/- 5.0% at 20 minutes after ACZ administration. In the affected side, timing of the maximum CBF increase caused by ACZ was remarkably delayed. CONCLUSION: Our method based on 99mTc-ECD SPECT also revealed delayed cerebral artery dilation in the affected side. It was suggested that ACZ reaction came out time dependently, as reported by Kuwabara et al.

Acetazolamide↗
PubMed2001

[A case with bacterial meningitis caused by cerebrospinal fluid rhinorrhea 22 years after head trauma].

A 38-year-old man with past history of head injury at the age of 16 years was admitted to our hospital in April, 2000 because of bacterial meningitis. At the end of March 2000, he experienced massive cerebrospinal fluid (CSF) rhinorrhea when he rested in bed, and subsequently he developed high-grade fever, headache, and nuchal stiffness in 2 weeks. His symptoms and signs improved with the antibiotic therapy alone. He had no recurrence of meningitis since then. A defect of his right skull base was clarified by 3D-CT, and multiplanar reconstruction (MPR)-CT. MRI brain scan showed the dislocation of the right frontal lobe into the ipsilateral anterior ethmoidal sinus. The diagnosis of CSF rhinorrhea and bacterial meningoencephalitis were made according to his clinical manifestations and neuroradiological studies including 3D-CT, MPR-CT and MRI brain scans. These imaging modalities, which described his head anatomy precisely, helped us to clarify the cause of his illness. When CSF rhinorrhea is present, it is important to take detailed past history of head trauma, even if the event occurred more than 20 years previously.

Adult↗
PubMed2000

Refolding of denatured/reduced lysozyme at high concentration with diafiltration.

Refolding of reduced and denatured protein in vitro has been an important issue for both basic research and applied biotechnology. Refolding at low protein concentration requires large volumes of refolding buffer. Among various refolding methods, diafiltration is very useful to control the denaturant and red/ox reagents in a refolding solution. We constructed a refolding procedure of high lysozyme concentration (0.5-10 mg/ml) based on the linear reduction of the urea concentration during diafiltration under oxygen pressure. When the urea concentration in the refolding vessel was decreased from 4 M with a rate of 0.167 M/h, the refolding yields were 85% and 63% at protein concentrations, 5 mg/ml and 10 mg/ml, respectively, after 11 h. This method gave a high productivity of 40.1,microM/h of the refolding lysozyme. The change in refolding yields during the diafiltration could be simulated using the model of Hevehan and Clark.

Animals↗
PubMed2000

Breeding of high-pyruvate-producing Torulopsis glabrata and amino acid auxotrophic mutants.

An efficient method for the isolation of pyruvate-producing mutants of Torulopsis glabrata IFO 0005 was established. On mutagenesis of the parent strain, mutants requiring polypeptone for complete growth were isolated. Seven mutants among one hundred auxotrophs produced higher concentrations of pyruvate than the parent strain. Among them, arginine (L-Arg) auxotrophic mutants and an isoleucine (L-Ile) and valine (L-Val) double auxotrophic mutant exhibited higher fermentative production of pyruvate from glucose than the parent strain. T. glabrata X-15 and X-17 required L-Arg for complete growth. T. glabrata X-68 absolutely required L-Ile and L-Val for complete growth. These three strains (X-15, X-17 and X-68) have more than 10% higher yields of pyruvate than the parent strain. Among them, the best strain regarding pyruvate productivity, T. glabrata X-15, accumulated 59.5 g/l free pyruvic acid (yield, 60.1%; conversion to pyruvic acid of added glucose in 43 h) on a 3-l jar-fermentor scale. This yield with strain X-15 represented a 12% increase compared to that obtained with the parent strain.

Journal Article↗
PubMed1999

Breeding of high-pyruvate-producing Torulopsis glabrata with acquired reduced pyruvate decarboxylase.

An efficient method for isolation of pyruvate-producing mutants of Torulopsis glabrata IFO 0005 was established. On mutagenesis of the parent strain, mutants requiring acetate for complete growth were isolated. The acetate-leaky auxotrophic mutants demonstrated higher fermentative yields of pyruvate from glucose than the parent strain. Thus, the pyruvate decarboxylase (PDC) activity of mutants requiring acetate for complete growth was lower than that of the parent strain. A decrease in the PDC activity would therefore block the formation of acetate via acetaldehyde and thus increase pyruvate production. Among the mutants, T. glabrata ACII-33 had accumulated free pyruvic acid (60.3 g/l) in 47 h (yield, 67.3%; conversion of pyruvic acid from glucose consumed) in a 3 l jar-fermentor. This yield by strain ACII-33 represented at 15% increase compared to that with the parent strain.

Journal Article↗
PubMed1999

[Technical investigation of cerebral blood flow measurements using the Patlak Plot method--a contrivance for positioning of the gamma camera at data collection in radionuclide angiography].

The time-activity curve for the aortic arch obtained from radionuclide angiography (RNA) is handled as an input function parameter according to the method of Matsuda et al., which determines regional cerebral blood flow non-invasively. The data are collected from a frontal view of the thorax captured by RNA by their method, however we encountered a case in which it was difficult to identify aortic arch in the data collection from the frontal view. The precise identification of the aortic arch was implemented when the RNA data were collected from the left anterior oblique view of the thorax. No significant difference was noted in the measured values between the data collection from the frontal view and from the left anterior oblique view. Our method seems to be useful modification of the Patlak plot method.

Aged↗
PubMed1999

[The significance of duplex ultrasonography examination in the acute cardioembolic stroke patients--with special attention to evaluation of internal carotid arteries].

The aim of this study is to clarify whether it is possible to diagnose occlusions of internal carotid arteries in the acute cardioembolic stroke patients by observing internal carotid arteries with duplex ultrasonography. Twenty-two consecutive patients underwent both duplex ultrasonography examination and cerebral angiography within 24 hours from the onset. Two cases who had no flow velocity and 8 cases who had systolic flow velocity but no anterograde diastolic flow velocity were all diagnosed as having internal carotid occlusions by cerebral angiography. Eleven of 22 cases who had anterograde diastolic flow velocity were diagnosed as having occlusions at distal side of M 1 portion or no occluded lesions. Besides, among 11 cases who were diagnosed as having occlusions of internal carotid arteries by cerebral angiography, five had end diastolic ratios (ED ratio) of common carotid arteries that were less than 4.0s. It is useful to evaluate the existence of anterograde diastolic flow velocity by duplex ultrasonography for the diagnosis of internal carotid occlusions in the acute cardioembolic stroke patients.

Acute Disease↗
PubMed1999

[Two cases of brain infarction associated with dissection of the thoracic aorta].

Case 1: a 57-year-old woman, who suddenly developed disturbance of consciousness, left spatial neglect, and left hemiparesis, was admitted to our hospital on the day 1. Brain CT scan on the day 2 revealed broad edematous infarction in her middle cerebral artery territory. The dissection of the thoracic aorta was observed with transesophageal echocardiography and brain embolism due to mural thrombus of the dissecting thoracic aorta was suspected. Case 2: a 67-year-old woman, who developed disturbance of consciousness, left spatial neglect, and left hemiparesis, was admitted to our hospital on the day 15. Brain CT scan on the day 15 showed non-edematous infarction in her middle cerebral artery territory. Contrast thoracic CT scan on the day 31 revealed the dissection of the thoracic aorta. No clinical exacerbation was observed, but brain CT scan on the day 94 showed broad infarction in her middle and anterior cerebral artery territories. It is considered that pseudolumen of the dissected thoracic aorta caused occlusion of her right internal carotid artery. Transesophageal echocardiography, or contrast thoracic CT scan should be considered for detection of the dissection of the thoracic aorta in the cases of cryptogenic stroke.

Aged↗
PubMed1998

Power Doppler enhancement of the placenta by dehydroepiandrosterone sulphate in term pregnancy.

We studied the effect of dehydroepiandrosterone sulphate (DHAS) on placental blood flow in 11 women with an uncomplicated pregnancy between 37 and 39 weeks of gestation. Power Doppler enhancement of the placenta was performed before and 60 minutes after the administration of a 200 mg intravenous dose of DHAS dissolved in 20 mL of 5% dextrose. Increased power Doppler enhancements of the placenta after DHAS injection were evident in each case studied. The power Doppler enhancement returned to the baseline imaging within 60 minutes. This DHAS loading test, assessed by means of power Doppler imaging, may be a useful technique when attempting to assess fetoplacental function in normal and high risk pregnancies.

Acetone↗
PubMed1998

Three-dimensional sonographic visualization of the fetal face.

OBJECTIVE: This study was done to show the potential of using three dimensional (3D) sonography to reveal fetal facial anomalies. SUBJECTS AND METHODS: Ninety-four healthy fetuses from 15 to 40 weeks' gestation were studied with a specially developed 3.5-MHz abdominal 3D transducer. This imaging system provided conventional two-dimensional (2D) sonographic images and also generated within seconds high-quality 3D images in the surface and transparent modes with no need for an external workstation. RESULTS: Using this imaging system, we obtained 2D and 3D images of fetal faces (forehead, eyes, nose, lips, and chin) at six gestational ages. At less than 24 weeks' gestation, 65% of facial structures were visualized. The image quality was slightly degraded because of the small fetal size. At or after 24 weeks' gestation, 84% of facial structures were revealed. We found no significant difference in image quality of the fetal face between 2D and 3D sonography. CONCLUSION: The new 3D sonographic technology can generate within seconds high-quality 3D images of the fetal face. The 3D technology seems to perform at least as well as conventional 2D sonography. Our results suggest that 3D sonography has the potential to supplement 2D sonography and might be useful in identifying malformations of the fetal face and chromosomal abnormalities in utero.

Face↗
PubMed1998

[Evaluation of transcranial-color flow imaging in detection of right-to-left intracardiac shunts].

We performed transesophageal echocardiography (TEE) and transcranial-color flow imaging (TC-CFI) in 38 patients (25 men, 13 women, mean age 51.5 years old) with cerebrovascular or cardiac disease in order to evaluate an accuracy in diagnosing right-to-left shunts (RLS) in the heart by TC-CFI as compared to TEE findings. We rapidly injected a mixture of 9 ml of cold saline and 1.0 ml of air into the antecubital vein during Valsalva maneuver. In TEE study, we took RLS positive when interatrial shunting of contrast microcavitations into the left atrium was visualized after complete opacification of the right atrium. In TC-CFI study, we considered RLS positive when we detected the high intensity transient signals (HITS) on the middle cerebral artery. The both studies were positive in 15 patients and negative in 19. Two patients were positive in TC-CFI and negative in TEE while the other two patients were negative in TC-CFI and positive in TEE. Therefore, the sensitivity of TC-CFI in diagnosing RLS was 88%, the specificity 90%, and the accuracy 89%. It seems that TC-CFI is a useful tool to estimate the RLS.

Aged↗