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S Yoshioka

Publications and source records attributed to S Yoshioka.

At least 73 records · Page 4Linked to original sources
PubMed1999

Parametric mapping of cerebral blood flow deficits in Alzheimer's disease: a SPECT study using HMPAO and image standardization technique.

UNLABELLED: This study assessed the accuracy and reliability of Automated Image Registration (AIR) for standardization of brain SPECT images of patients with Alzheimer's disease (AD). Standardized cerebral blood flow (CBF) images of patients with AD and control subjects were then used for group comparison and covariance analyses. METHODS: Thirteen patients with AD at an early stage (age 69.8+/-7.1 y, Clinical Dementia Rating Score 0.5-1.0, Mini-Mental State Examination score 19-23) and 20 age-matched normal subjects (age 69.5+/-8.3 y) participated in this study. 99mTc-hexamethyl propylenamine oxime (HMPAO) brain SPECT and CT scans were acquired for each subject. SPECT images were transformed to a standard size and shape with the help of AIR. Accuracy of AIR for spatial normalization was evaluated by an index calculated on SPECT images. Anatomical variability of standardized target images was evaluated by measurements on corresponding CT scans, spatially normalized using transformations established by the SPECT images. Realigned brain SPECT images of patients and controls were used for group comparison with the help of statistical parameter mapping. Significant differences were displayed on the respective voxel to generate three-dimensional Z maps. CT scans of individual subjects were evaluated by a computer program for brain atrophy. Voxel-based covariance analysis was performed on standardized images with ages and atrophy indices as independent variables. RESULTS: Inaccuracy assessed by functional data was 2.3%. The maximum anatomical variability was 4.9 mm after standardization. Z maps showed significantly decreased regional CBF (rCBF) in the frontal, parietal and temporal regions in the patient group (P < 0.001). Covariance analysis revealed that the effects of aging on rCBF were more pronounced compared with atrophy, especially in intact cortical areas at an early stage of AD. Decrease in rCBF was partly due to senility and atrophy, however these two factors cannot explain all the deficits. CONCLUSION: AIR can transform SPECT images of AD patients with acceptable accuracy without any need for corresponding structural images. The frontal regions of the brain, in addition to parietal and temporal lobes, may show reduced CBF in patients with AD even at an early stage of dementia. The reduced rCBF in the cortical regions cannot be explained entirely by advanced atrophy and fast aging process.

Aged↗
PubMed1999

[Intracranial primitive neuroectodermal tumor in an infant: a case report].

A 2-month-old girl with a supratentorial primitive neuroectodermal tumor (PNET), which extended into the skull, is herein presented. The patient underwent total removal of the tumor and also received a course of postoperative chemotherapy. After a follow-up period of 12 months, the infant is alive without recurrence. Histologically, the tumor was composed of poorly differentiated neuroectodermal cells, and these neoplastic cells showed a mild immunohistochemical reaction for GFAP and synaptophysin, and a moderate reactivity for neuron specific enolase and vimentin. In addition, a moderate level of immunoreactivity for HBA71 antigen (p30/32M1C2), which is the product of the M1C2 gene and is found in peripheral PNETs but not in central PNETs, was noted in many neoplastic cells. Although this tumor was located intracranially, it may be classified as a peripheral PNET.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

[A case of multiple bone metastases from advanced breast cancer effectively treated with pamidronate].

A 57-year-old woman, with bone, lymph node and skin metastases underwent mastectomy and extirpation of skin tumors. Chemoenderine-therapy was performed from the 15th day after operation, with a toremifene and CEF regimen consisting of cyclophosphamide, epirubicin and 5-fluorouracil. She had nausea and neurological symptoms from hypercalcemia (21.5 mg/dl) on the 28th day after operation. Her serum PTHrP level was found to be high at 214 pmol/l. We administered pamidronate in a dose of 45 mg biweekly, and she improved. The CEF regimen and pamidronate therapy was continued for 6 cycles and the regions of bone metastases were reduced on the bone scintography. Thereafter she has been administered pamidronate 30 mg/4 weeks as an outpatient with no further symptoms, and serum Ca and PTHrP have remained normal. In conclusion, pamidronate combined with chemotherapy can be a therapeutic option for not only hypercalcemia but also bone metastases of breast cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

[Evaluation of intermittent hepatic arterial infusion chemotherapy for multiple liver metastasis of colorectal cancer].

Five patients with synchronous multiple hepatic metastasis of colorectal cancer were treated with hepatic arterial infusion chemotherapy. All cases received intermittent 5-FU infusion (5-FU 250-1,000 mg/2-3 hrs/1-2 weeks) on an outpatient basis. In the evaluation of 5 cases, 3 PR and 1 NC were observed. One case administered arterial infusion for adjuvant chemotherapy has no recurrence in liver. In two patients, extra-hepatic metastases were found. In conclusion, this therapy was effective and useful for hepatic metastasis. Moreover, other forms of treatment for extra-hepatic metastasis must be used.

Adult↗
PubMed1999

[Intraperitoneal cisplatinum chemotherapy in patients with carcinomatous peritonitis due to colorectal scirrhous cancer--case report].

Two patients received intraperitoneal cisplatinum chemotherapy for carcinomatous ascites due to colorectal cancer recurrence. The patients were a 47-year-old man who had rectal cancer and 51-year-old woman who had colon cancer. They had received the operation and adjuvant chemoradiation therapy and chemotherapy respectively. However, five months and two years after resection, respectively, they presented massive ascites due to carcinomatous peritonitis and were given cisplatin injection intraperitoneally. The amount of ascites was significantly diminished. One patient had been discharged and been able to stay at home, and the other patient underwent gastrostomy for ileus. The results suggested that intraperitoneal cisplatinum chemotherapy may be useful for the patient with carcinomatous ascites due to colorectal cancer.

Adenocarcinoma, Scirrhous↗
PubMed1999

[Palliative chemo-radiotherapy for abdominal recurrence of esophageal carcinoma--case report].

A 71-year-old man with stage IV esophageal carcinoma was treated by chemo-radiotherapy (5-FU 500 mg/day + CDDP 10 mg/day for 4 weeks and 67.6 Gy of RT). The esophageal tumor showed a complete response to the treatment. Six months later, he had obstructive jaundice due to an abdominal recurrent mass. A secondary (palliative) CRT was performed (5-FU 500 mg/day + CDDP 10 mg/day for 3 weeks and 45 Gy of RT). The abdominal tumor became remarkably smaller and jaundice disappeared. Though the patient died from pulmonary carcinomatous lymphangitis, the primary lesion showed CR. CRT was very effective for local treatment and for palliative therapy.

Aged↗
PubMed1998

Centrally administered TRH-induced insulin secretion is impaired in the Otsuka-Long-Evans-Tokushima Fatty rats, a model of spontaneous non-insulin-dependent diabetes mellitus.

To investigate whether insulin secretion induced by stimulation of the vagus nerve is preserved or impaired in Otsuka-Long-Evans-Tokushima Fatty (OLETF) rats, we injected 10(-8) mol of thyrotropin-releasing hormone (TRH) into the third cerebral ventricle and determined the serum level of insulin in the unanesthetized, unrestrained rats. Intracerebroventricular (i.c.v.) injection increased the serum levels of glucose and insulin in both OLETF and Long-Evans-Tokushima-Otsuka (LETO) rats, a nondiabetic control strain, at 8-12 weeks of age. At 24-28 weeks of age, the increased level of glucose in OLETF rats was comparable to LETO rats but that of insulin was lower than control after the i.c.v. injection of TRH. Pretreatment with i.v. atropine had no significant effect on such hyperglycemia. However, the increases in the serum levels of insulin were suppressed in both OLETF and LETO rats. The plasma levels of epinephrine, norepinephrine, and glucagon rose significantly after TRH. There was no significant difference in the levels of any hormones between the two groups. In OLETF rats at 24-28 weeks of age, i.v. glucose load induced significantly higher serum levels of glucose and insulin than LETO rats. The results suggest that the vagus nerve-mediated insulin secretion is impaired in OLETF rats, similar to an autonomic diabetic neuropathy in the early stage of diabetes. This impairment may play some role in deteriorating glucose tolerance in this spontaneously developed diabetes model.

Animals↗
PubMed1998

Hepatic venous hemoglobin oxygen saturation predicts regenerative status of remnant liver after partial hepatectomy in rats.

This study was designed to evaluate the use of hepatic venous hemoglobin oxygen saturation (ShVO2) as an indicator of hepatic oxygen supply-demand relation and also regenerative status of the liver after partial hepatectomy in rats. We assessed the ShVO2 levels for 7 days, as well as hepatic hemodynamics, oxygen consumption, DNA synthesis and energy charge of the remnant liver for 3 days after 50% hepatectomy or sham operation. Total hepatic oxygen consumption (HVO2) per liver weight, hepatic oxygen extraction ratio (HO2ER), and DNA synthesis were significantly elevated at days 1 and 3 after hepatectomy, compared with the preoperative levels. Meanwhile, significantly decreased ShVO2 levels were observed at days 1 and 3, and the ShVO2 levels were significantly correlated with the HVO2. Furthermore, the decreased ShVO2 levels were synchronized with the increased DNA synthesis in the remnant liver. Energy charge levels were also significantly decreased at day 1 after hepatectomy. These results suggest that the regenerating liver demands an increased amount of oxygen for mitochondrial oxidative phosphorylation to restore hepatic energy charge. In conclusion, the ShVO2 after hepatectomy may reflect oxygen metabolic status in the remnant liver and could be useful for estimating liver regeneration.

Animals↗
PubMed1998

Use of automated image registration to generate mean brain SPECT image of Alzheimer's patients.

UNLABELLED: The purpose of this study was to compute and compare the group mean HMPAO brain SPECT images of patients with senile dementia of Alzheimer's type (SDAT) and age matched control subjects after transformation of the individual images to a standard size and shape. METHODS: Ten patients with Alzheimer's disease (age 71.6 +/- 5.0 yr) and ten age matched normal subjects (age 71.0 +/- 6.1 yr) participated in this study. Tc-99m HMPAO brain SPECT and X-ray CT scans were acquired for each subject. SPECT images were normalized to an average activity of 100 counts/pixel. Individual brain images were transformed to a standard size and shape with the help of Automated Image Registration (AIR). Realigned brain SPECT images of both groups were used to generate mean and standard deviation images by arithmetic operations on voxel based numerical values. Mean images of both groups were compared by applying the unpaired t-test on a voxel by voxel basis to generate three dimensional T-maps. X-ray CT images of individual subjects were evaluated by means of a computer program for brain atrophy. RESULTS: A significant decrease in relative radioisotope (RI) uptake was present in the bilateral superior and inferior parietal lobules (p < 0.05), bilateral inferior temporal gyri, and the bilateral superior and middle frontal gyri (p < 0.001). The mean brain atrophy indices for patients and normal subjects were 0.853 +/- 0.042 and 0.933 +/- 0.017 respectively, the difference being statistically significant (p < 0.001). CONCLUSION: The use of a brain image standardization procedure increases the accuracy of voxel based group comparisons. Thus, intersubject averaging enhances the capacity for detection of abnormalities in functional brain images by minimizing the influence of individual variation.

Aged↗
PubMed1998

A comparison of Tc-99m HMPAO brain SPECT images of young and aged normal individuals.

The purpose of this study was to examine the normal distribution patterns of 99mTc-HMPAO (HMPAO) in young and aged normal individuals and to clarify differences between the distribution patterns of the two groups by means of an anatomical standardization technique. The tracer distribution was measured with HMPAO and SPECT in 18 normal subjects; age range 20-81 yrs. SPECT images were globally normalized by averaging whole brain radioactivity counts to 100 counts/voxel. The SPECT images for each subject were transformed into the standard brain anatomy by means of a computerized brain atlas, together with each subject's CT images. Mean and SD images for young (28.8 +/- 6.4 yrs) and aged groups (62.3 +/- 10.2 yrs) were then calculated on a voxel-by-voxel basis. Statistically significant differences between young and aged groups were observed in the relative tracer distribution patterns. In the aged group, relative decreases were found in the cortical areas of the frontal and temporal lobes, limbic areas and basal ganglia regions. The results, as visualized changes in tracer distribution patterns with aging, may contribute to more accurate clinical diagnosis.

Adult↗
PubMed1998

Interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) enhance lipopolysaccharide binding to neutrophils via CD14.

OBJECTIVE: Lipopolysaccharide (LPS), a potent and pleiotropic stimulator of immune cells, binds to neutrophils via CD14, but less densely than to monocytes. The present study was designed to investigate whether cytokines modulate LPS binding to neutrophils via CD14. METHODS: Neutrophils were cultured with LPS after pretreatment with cytokines, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), interleukin-1 alpha (IL-1alpha), or granulocyte-colony stimulating factor (G-CSF). Binding of LPS and CD14 expression on neutrophils were analyzed by flow cytometry, using anti-LPS and anti-CD14 monoclonal antibodies (mAb). RESULTS: LPS alone showed only slight binding to neutrophils, but pretreatment with IFN-gamma or TNF-alpha before LPS exposure markedly increased LPS binding and CD14 expression on the surfaces of neutrophils. The dramatic increase in LPS binding was not seen with IL-1alpha or G-CSF. Anti-CD14 blocking mAb completely inhibited the binding effect. CONCLUSIONS: These results demonstrate that IFN-gamma and TNF-alpha enhance LPS binding to neutrophils via CD14, suggesting that the priming effect of cytokines on neutrophils is important for LPS binding.

Antibodies, Monoclonal↗
PubMed1998

Clinical features of moyamoya disease in sibling relations under 15 years of age.

This study was undertaken to define the clinical features of moyamoya disease in sibling relations less than 15 years of age. We analysed five pairs of siblings (6 boys, 4 girls) with moyamoya disease from among 56 moyamoya patients less than 15 years of age. Of 56 paediatric patients with moyamoya disease, 5 were sibling pairs. At onset of the disease, all patients were under 10 years of age. Clinical manifestations in the proband and the affected sibling tended to present as transient ischaemic attacks; none of the 10 patients presented with intracranical haemorrhage. The probands were not always the older sibling, however, the time lapse between disease onset in the proband and his/her sibling was less than one year. Among the sibling pairs, there was no striking difference in disease staging based on angiographic findings. The incidence of sibling occurrence of moyamoya disease appears to be higher than previously assumed and the family of children with moyamoya disease should be cautioned that their other children have an increased risk of developing the illness.

Adolescent↗
PubMed1998

Extra-anal mucosectomy: laparascopic-assisted endorectal pull-through using a prolapsing technique.

BACKGROUND/PURPOSE: The mucosectomy of the aganglionic rectal mucosa has been performed transabdominally in the Soave procedure. Recently, mucosectomy with transanal approach was reported both in the laparoscopic and the open surgical procedure. However, the operative view and working field are restricted because the dissection has to be done in the anal canal. The authors report an innovative approach, an extra-anal mucosectomy, to perform mucosectomy in the Soave procedure for Hirschspung's disease in combination with the laparoscopic-assisted prolapsing technique. METHODS: Four patients underwent laparoscopic surgery for Hirschsprung's disease with extra-anal mucosectomy between 1995 and 1997. One 10-mm and 5-mm ports were used throughout the operation. The rectum was pulled out through the anal canal to create a rectal prolapse and was divided outside the anal canal. The mucosectomy was performed in the everted rectal mucosa outside the anal canal to the level of dentate line. The colon was sutured to the anal mucosa 2 mm above the dentate line. Mean operative time was 3 hours. RESULTS: The present technique made the whole mucosectomy possible under direct observation. CONCLUSION: The extra-anal mucosectomy in conjunction with a laparoscopic-assisted prolapsing technique seems to be a safe and reliable modality in the surgical treatment of Hirschsprung's disease.

Anal Canal↗