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Biomedical subjects

S Yamaguchi

Publications and source records attributed to S Yamaguchi.

At least 253 records · Page 14Linked to original sources
PubMed2000

[Renomedullary interstitial cell tumor: a case report].

Renomedullary interstitial tumor is a common tumor in the renal medulla, present in 26-41% of consecutive autopsy specimens. However clinically evident case is infrequent because this lesion is usually small (less than 3 mm). We report a case of renomedullary interstitial tumor in a 76-year-old woman. Ultrasonogram incidentally revealed a mass in the left kidney while she visited to the hospital for hypertension and unstable angina. A CT scan showed a 2 cm mass that was not clearly enhanced. MR images showed low signal intensity in both T1 and T2 images. Arteriography demonstrated no neo-vascularity. Those findings showed that this lesion was benign one or hypovascular carcinoma. So Left nephrectomy was performed and histological examination revealed a renomedullary interstitial tumor.

Aged↗
PubMed2000

[Myelopathy caused by tentorial dural arteriovenous fistula: a rare case report].

A 51-year-old man with myelopathy due to intracranial dural arteriovenous fistula (dural AVF) is reported. At age 46, the patient experienced subarachnoid hemorrhage caused by rupture of the dural AVF and underwent embolization of the lesion at another hospital. At this time, the patient complained of numbness in his legs and showed paraplegic gait disturbance. MRI scan revealed swelling of the cervical spinal cord. Cerebral angiograms demonstrated the recurrence of tentorial dural AVF fed by bilateral meningohypopheseal trunks and the right posterior inferior cerebellar artery. Arteriovenous shunt (AV shunt) flow was drained into the anterior spinal vein. It seemed that the swelling of the spinal cord and myelopathy was caused by venous hypertension of spinal veins. After surgical interruption of the right petrosal vein which connected dAVF with cerebellar veins, AV shunt was obliterated successfully. Postoperative cerebral angiograms showed disappearance of dural AVF. The patient became ambulant and his cervical spinal cord appeared normal on the postoperative MRI scan. Surgical interruption of the draining vein was simple, effective and essential treatment.

Arteriovenous Fistula↗
PubMed2000

Gender effects on age-related changes in brain structure.

BACKGROUND AND PURPOSE: Previous reports have suggested that brain atrophy is associated with aging and that there are gender differences in brain atrophy with aging. These reports, however, neither exclude silent brain lesions in "healthy subjects" nor divide the brain into subregions. The aim of this study is to clarify the effect of gender on age-related changes in brain subregions by MR imaging. METHODS: A computer-assisted system was used to calculate the brain matter area index (BMAI) of various regions of the brain from MR imaging of 331 subjects without brain lesions. RESULTS: There was significantly more brain atrophy with aging in the posterior parts of the right frontal lobe in male subjects than there was in female subjects. Age-related atrophy in the middle part of the right temporal lobe, the left basal ganglia, the parietal lobe, and the cerebellum also was found in male subjects, but not in female subjects. In the temporal lobe, thalamus, parieto-occipital lobe, and cerebellum, brain volume in the left hemisphere is significantly smaller than in the right hemisphere; sex and age did not affect the hemisphere differences of brain volume in these regions. CONCLUSION: The effect of gender on brain atrophy with aging varied in different subregions of the brain. There was more brain atrophy with aging in male subjects than in female subjects.

Adult↗
PubMed2000

[Anesthetic management of a patient with West syndrome].

A 21-year-old female with West syndrome was scheduled for resection of hordeolum. She had an episode of convulsion at three months of age, and was diagnosed as having West syndrome at one year of age. She had epileptic seizures twice a week in spite of administration of phenytoin, clonazepam and sodium valproate. These drugs had been administered till the morning of the surgery. After premedication with atropine 0.25 mg, anesthesia was induced with propofol (12-->10-->8 mg.kg-1.h-1). The tracheal intubation was performed with vecuronium 0.1 mg.kg-1 and anesthesia was maintained with continuous infusion of propofol 6-8 mg.kg-1.h-1 and local infiltration with 1.0% lidocaine 5 ml. We administered phenytoin to prevent epileptic seizures during the surgery. No epileptic seizures occurred perioperatively. We conclude that propofol may be useful for a patient with West syndrome, and we should be careful not to lower the threshold for convulsion during the perioperative period.

Adult↗
PubMed2000

[A case of riboflavin-responsive multiple acyl-CoA dehydrogenase deficiency (glutaric aciduria type II)].

We reported a male infant with multiple acyl CoA dehydrogenase deficiency, probably due to electron transfer flavoprotein dehydrogenase deficiency. He was noted to have severe muscle weakness, a high serum creatine kinase (CK) level up to 6920 IU/L, lipid storage myopathy and fatty liver at 6 months of age. A GC/MS analysis of urinary organic acids showed excess excretion of dicarboxylic acids, including glutaric, 2-hydroxyglutaric, adipic, suberic, sebacic, malonic, ethylmalonic and methylsuccinic acids. On a urinary acylglycine analysis, hexanoylglycine and suberylglycine were increased, but not isovalerylglycine, in amount. No ketosis was noted. The muscle pathology showed increased oil-red O positive lipid droplets of various sizes indicative of lipid storage myopathy. There was diffuse decrease in the activity of cytochrome c oxidase. No ragged-red fibers were noted. His clinical symptoms improved remarkably after the administration of riboflavin (100 mg/day) and L-carnitine (1000 mg/day). He was then diagnosed as having probable riboflavin-responsive multiple acyl-CoA dehydrogenase deficiency. The glutaryl CoA dehydrogenase activity in lymphocytes was normal, as were the alpha- and beta-subunits of electron transfer flavoprotein. These findings led us to suspect electron transfer flavoprotein dehydrogenation deficiency. Although he had several episodes of short-term deterioration in clinical and laboratory findings, he developed normally with normal intelligent till 10 years of age.

Acyl-CoA Dehydrogenases↗
PubMed2000

[Anesthetic management of bilateral lung lavage for pulmonary alveolar proteinosis--comparison between sevoflurane and propofol].

A 55-year-old man with pulmonary alveolar proteinosis underwent lung lavage under general anesthesia using sevoflurane three years ago. Although transient hypoxia occurred postoperatively, there were no complications. Because of the recent deterioration of his symptoms, he was rescheduled for lung lavage. Anesthesia was induced with propofol 120 mg and fetanyl 0.2 mg. Vecuronium 7 mg was administered to facilitate tracheal intubation using a double-lumen tube. Anesthesia was maintained with propofol 4 mg.kg-1.h-1. Electrocardiogram, blood pressure, SPO2, EtCO2 and rectal temperature were monitored intraoperatively. We also checked PaO2 when necessary. Although transient hypoxia occurred after the procedure, it receded spontaneously. Since inhalation anesthetics inhibit hypoxic pulmonary vasoconstriction, intravenous anesthetics may be more useful for patients with severe pulmonary alveolar proteinosis.

Anesthesia, General↗
PubMed2000

[Usefulness of laryngeal mask for difficult intubation in a child with congenital laryngeal webs].

We report a case of difficult intubation with congenital laryngeal web. An 11-year-old boy was scheduled for urinary surgery. After anesthetic induction, the anesthesiologist encountered resistance at the vocal cord preventing satisfactory intubation. A size 3 laryngeal mask was immediately inserted, and an adequate airway was obtained. We found a laryngeal web at the vocal cord by bronchoscope inserted thorough the laryngeal mask. The peroperative course was uneventful. Immediately after removal of the laryngeal mask, the patient developed airway obstruction due to sputum and/or laryngeal spasm. The obstruction was relieved through application of positive pressure ventilation and aspiration of the sputum.

Airway Obstruction↗
PubMed2000

[Two cases of extreme hemodilution caused by massive hemorrhage immediately after start of operation].

We describe two cases of extreme hemodilution due to large amounts of fluid infusion for unexpected massive hemorrhage. In both cases, unexpected hemorrhage with difficult hemostasis occurred within 60 min after the start of the operation. For lack of transfused blood, large amounts of fluid infusion using crystalloid and colloid solutions including 5% albumin, plasma expander and lactated Ringer's solution were administered to maintain circulatory blood volume. The hemoglobin concentration and hematocrit had been below 2.0 g.dl-1 and 10% for approximately one hour, respectively. The extreme hemodilution improved by the urgent blood transfusion. In one case, intraoperative autotransfusion with Cell-Saver was performed. In spite of intraoperative extreme hemodilution, their postoperative courses were uneventful. Intraoperative awareness was present in both cases.

Adult↗
PubMed2000

[A case of bilateral testicular tumors with congenital adrenal hyperplasia].

We report a case of congenital adrenal hyperplasia (CAH) occurring in a 21-year-old man. He was found to have 21-hydroxylase deficiency shortly after birth in search for the cause of vomiting and adrenal insufficiency, and placed on steroid therapy. He had an uneventful childhood with normal onset of puberty. At the age of 21 years he was hospitalized with bilateral testicular masses. They were non-tender, firm and nodular on palpation. The levels of adrenocorticotrophic hormone (ACTH), 17 alpha-hydroxyprogesterone (17 alpha-OHP) were found to be elevated. Testicular biopsy revealed that the nodule comprised mainly eosinophilic sheets and nests and polygonal cells with abundant, granular cytoplasm, but no crystals of Reinke were seen. Testicular tumor with congenital adrenal hyperplasia is typically bilateral and develops in untreated or inadequately treated males with CAH.

17-alpha-Hydroxyprogesterone↗
PubMed2000

[Clinical evaluation of granisetron hydrochloride for nausea and vomiting induced by oral anticancer drugs].

We investigated the antiemetic effect, safety and usefulness of granisetron hydrochloride tablets on nausea and vomiting induced by oral anticancer drugs used in chemotherapy for gastric cancer and colorectal cancer. In the present trial, oral administration of granisetron hydrochloride was performed during 5 days after nausea or vomiting. 1) Clinically, the effective rate of granisetron hydrochloride (the percentage of cases in which the drug was assessed as "Remarkably effective" or "Effective") was more than 75% on each day of administration. There were no adverse events or abnormal laboratory tests. 2) In terms of usefulness, granisetron hydrochloride was rated "Extremely useful" or "Useful" in 17 out of 23 cases (78.2%). The above results have shown that granisetron hydrochloride tablets, administrated orally once daily at a dose of 2 mg, have an excellent antiemetic effect, and that this is a safe and useful drug.

Administration, Oral↗
PubMed2000

[Damage of a laryngeal mask airway during anesthesia].

A 21-year-old man was scheduled for fixation of a fractured radius and ulna under general anesthesia using a laryngeal mask airway (LM). Anesthesia was induced with propofol 120 mg and fentanyl 0.1 mg. After administration of vecuronium 6 mg, we attempted insertion of the LM (# 5). The first trial was unsuccessful because the tube of the LM was bent in the pharynx. We attempted it again and the LM was successfully inserted. It was connected with the anesthetic circuit, and manual ventilation was started. However, the LM was suddenly broken at the basal part of the tube connector before the start of operation, and it became detached from the anesthetic circuit. Therefore, we removed the remaining LM from the mouth, and inserted a new LM (# 5). The peroperative course was uneventful. We conclude that inspection of a recycled LM is important before using it in order to prevent such an event as the present case.

Adult↗
PubMed2000

[Efficacy of sustained-released theophylline on peak expiratory flow rate in asthmatic patients].

Nocturnal worsening is an important problem in asthma management. We evaluated the efficacy of two sustained-released theophylline formulations, administered twice-a-day (TD) and once-a-day (UP). In 20 asthmatic patients with low peak expiratory flow rate (PEF) in the morning (< 80% of predicted) administered TD (mean dose 475 mg/day) for 2 weeks, we evaluated PEF, diurnal variability of PEF, symptom score, results of spirometry and serum theophylline concentration (STC) and then changed theophylline, from TD to UP (mean dose 470 mg/day) for 2-4 weeks. PEF in the morning was higher during the UP period (mean +/- SD: 335 +/- 110 L/min) than during the TD period (mean +/- SD: 308 +/- 95 L/min) (p < 0.05), and diurnal variabirity of PEF was lower during the UP period (17.1 +/- 8.0%) than TD period (22.9 +/- 13.4%) (p < 0.05). However, there were no changes in PEF at night or daytime, symptom score, spirometry parameters or STC during the study period. The improvement in morning PEF observed in this study was consistent with the differences in pharmacokinetics between the two theophylline formulations. Morning PEF was increased during the UP period, probably because STC in the early morning during the UP period was higher than STC during the TD period.

Adult↗
PubMed2000

[Malignant peripheral nerve sheath tumor with divergent cartilage differentiation from the acoustic nerve: case report].

Malignant peripheral nerve sheath tumors(MPNSTs) of the acoustic nerve are very rare. Only seven cases of MPNST arising from the acoustic nerve have been reported. The authors present a case of MPNST with divergent cartilage and melanotic differentiation of the acoustic nerve. The patient was a 69 year old man admitted to our neurosurgical service in January 1999 complaining of left facial nerve palsy and hearing difficulty of his left ear. The initial CT showed a tumor at the left cerebellopontine angle region. On MRI the tumor was depicted as low intensity on T 1-weighted image and high intensity on T 2-weighted image, the mass was heterogeneously enhanced after administration of Gd-DTPA. The partial removal of the tumor was performed in January 1999. He was discharged February 1999. But he was admitted again because of progressive cerebellar ataxia. MRI showed the rapid regrowth of the residual tumor. In March 1999, complete removal of the tumor was performed. Histopathological analysis revealed a malignant spindle cell neoplasm with divergent cartilage and melanotic differentiation. We review the relevant literature concerning MPNST of the acoustic nerve and discuss the clinical features of malignant eighth cranial nerve tumor.

Aged↗
PubMed2000

[Optimal dosage of UFT in a weekday-on/weekend-off schedule as a postoperative adjuvant chemotherapy for colorectal cancer].

In evaluations of adjuvant chemotherapy with oral anticancer agents, compliance in taking the drug as prescribed (compliance), adverse reactions, and feasibility are important factors in setting the dose. A weekday-on/weekend-off schedule, in which 600 mg/day of UFT was taken for 5 consecutive days and not taken on the following 2 days, was carried out as a postoperative adjuvant chemotherapy for one year in 87 patients with colorectal cancer who had undergone potentially curative resection. The prescribed dose and the dose of ingestion confirmed by physician interview were both highly consistent with the dose of ingestion according to the patients' self reports, with consistency rates of more than 94% for both. Relative performance (RP) yielded a value of 0.72, and individual dose intensity (IDI) yielded 0.8 on average. Female gender, low body weight, and low body surface area were factors that negatively affected feasibility. None of the adverse reactions was serious. Based on the feasibility and adverse reactions, the dosage of UFT should be set according to the body surface area at 375-425 mg/m2/day. When this schedule is used as one arm of a controlled study, it is suggested that the dose should be decided with 400 mg/m2 as a guideline.

Adult↗
PubMed2000

[Acute effects of oxygen on dyspnea and exercise tolerance in patients with pulmonary emphysema with only mild exercise-induced oxyhemoglobin desaturation].

The effects of oxygen on dyspnea and exercise tolerance during a 6-mimute walk test were examined in 10 patients with chronic pulmonary emphysema (CPE) who had only mild hypoxemia at rest (PaO2 > 60 Torr) and mild exercise-induced oxyhemoglobin desaturation (lowest SpO2 > 88%) on compressed air. As a whole, oxygen supplementation (2 l/min) resulted in a 7% increase in the distance walked in 6 min (6 MD), a 3% increase in the lowest SpO2, and an 8% decrease in the dyspnea score. In 6 of 7 patients with severe airflow limitation (one-second forced expiratory volume (FEV1) < 40% of predicted value), 6 MD (7-15%) increased significantly on oxygen, an improvement that correlated significantly with FEV1 (r = -0.65, p < 0.05). These results suggest that supplementary oxygen improves dyspnea and exercise tolerance in CPE patients with only mild exercise-induced hypoxemia despite severe airflow limitation. The long-term efficacy of oxygen in such patients needs further study.

Aged↗