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Biomedical subjects

Y Yamazaki

Publications and source records attributed to Y Yamazaki.

At least 361 records · Page 20Linked to original sources
PubMed1995

Thermosensitization of murine FM3A cells by transient incubation at low culture temperatures.

We show that when murine FM3A cells maintained at 37 degrees C were incubated at low culture temperatures between 24 degrees and 33 degrees C for 12-24 h, they became thermosensitive as compared to those incubated at 37 degrees C. The synthesis and accumulation of inducible HSP70 and constitutive HSC70 by heat shock decreased in cells incubated at 33 degrees C, whereas no such decreases were found in cells incubated at 37 degrees C. The accumulation of HSP105 because of heat shock also decreased in cells incubated at 33 degrees C. The decreased inducibility of HSP70, HSC70, and HSP105 by heat shock may in part be responsible for the increase seen in the thermosensitivity of the cells. Furthermore, the cellular concentration of HSP105 decreased in cells incubated at 33 degrees C but not in those incubated at 37 degrees C, whereas the concentration of HSC70 did not change at all in cells incubated at either temperature. The cellular content of HSP105, but not of HSC70, therefore may be a good indicator of the thermoresistant state of cells.

Animals↗
PubMed1995

Serum insulin-like growth factor-I (IGF-I) in normal Japanese adults.

To evaluate surgical and medical treatment of GH-producing pituitary tumors and GH supplement to GH-deficient patients, we determined the reference values for serum IGF-I in Japanese adults. The serum IGF-I concentration in 454 apparently healthy subjects (246 men aged 21-70 years and 208 women aged 21-72 years) was measured with a commercial RIA kit after acid-ethanol extraction. The concentration of serum IGF-I decreased with age in both sexes. The IGF-I in females was significantly higher than that in males in the group aged 21-30 years and lower in the group aged 61-72 years. We conclude that an age- or sex-related standard is necessary for comparing IGF-I values in patients.

Adult↗
PubMed1995

Changes in nitric oxide synthase activities in the cerebellum during development and aging of C57BL/6 mice.

Nitric oxide (NO) is one of the neurotransmitters in the cerebellum. Activities of NO synthase and densities of granule cells were determined in the cerebellum in an attempt to elucidate a mechanism of biochemical changes on the anatomical basis during aging. Activities of Ca2+/calmoduline dependent NO synthase were measured in the cerebellum in male and female mice, from 18 gestation days to 28 months of age. There were significant differences in NO synthase activities among the groups of prenatal (18 gestation days), middle aged (5-18 months) and old aged (21-28 months) mice. Between groups of old and middle ages, a significant decrease with aging was found in the mean density of granular cells, which express NO synthase. Changes in NO synthase activities and granule cell densities occurred to a similar degree between old and middle ages. The present data suggest that an age-associated rise and fall of its activities likely occur in parallel with those of granule cell densities, and thus may represent impairment of cerebellar function during aging.

Aging↗
PubMed1995

[A case of urachal carcinoma associated with elevated levels of CA19-9].

A 53-year-old man was admitted with the chief complaint of gross hematuria. Cystoscopic examination revealed a non-papillary tumor at the dome of the bladder. The plasma level of CA19-9 was markedly elevated before treatment. Total cystectomy with en bloc removal of the tumor and radical lymphadenectomy were performed under the diagnosis of urachal carcinoma. The plasma CA19-9 level decreased to the normal level after operation and was well correlated with postoperative course. The monitoring of CA19-9 may be useful for follow up in patients showing a high elevation of CA19-9.

Adenocarcinoma↗
PubMed1995

The influence of arm movements on a vertical jump.

The influence of arm lowering movements (ALM) on a vertical jump with all but the ankle joints immobilized was studied in five healthy volunteers. Subjects were instructed to rapidly lower both arms after takeoff when jumping from an initial position with the elbows flexed. They performed the jumps either with their hands empty or holding 4 kg dumbbells. ALM prolonged the time subjects were airborne, especially when holding the dumbbells. Protocol for the experiment required that subjects maintain maximum angular velocity of the ankle joint, vertical platform force, and electromyographic monitoring from the triceps surae muscle. Positive acceleration of the head increased in the ALM jumps, and became even more pronounced when the jumps were performed with dumbbells. This increase in head acceleration was inversely proportional to the downward acceleration of the hands. These results indicate that prolonging a vertical jump depends on ALM in the air.

Acceleration↗
PubMed1995

[Characteristic neurological signs in patients with cervical disc disease].

In cervical radiculopathy, neurological findings for the upper extremities and the responsible level of the radices have been precisely detailed. However, in cases of cervical spondylotic myelopathy, it is not always easy to determine the responsible level of the cervical spine solely based on neurological findings. To disclose characteristic neurological lesions of the upper extremities, if any, for different locations of disc disease, 49 patients with cervical disc protrusion at single levels, confirmed by magnetic resonance imaging, were analyzed. Thirty-six patients demonstrated long tract signs (LTS) concomitant with segmental signs in the upper extremities, and 13 patients had no LTS. Except for deep tendon reflexes and the extent of dysesthesia in the upper extremities, there were no characteristic neurological findings, such as muscle atrophy, loss of muscle strength, extent of hypalgesia, or hypesthesia, pointing to the responsible compression site. In the 13 patients without LTS, the extent of dysesthesia and diminution of deep tendon reflexes proved to be completely in agreement with results for radiculopathy: 9 had protruded discs at the C56 level and described dysesthesia in the thumb and the index finger with deep tendon reflexes in the biceps and brachioradialis being diminished. The remaining 4 had protruded discs at the C67 level and described dysesthesia in the middle finger. Their deep tendon reflexes in the triceps were diminished. A clear contrast was observed for the patients with LTS. Four out of 36 patients had C34 protruded discs and did not complain of dysesthesia in any digits. Their deep tendon reflexes were exaggerated in all muscles in the upper extremities.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[The relationship between visual field defects and clinical factors in normal-tension glaucoma].

We investigated the relationship between visual field defects and some clinical factors in 30 eyes of 30 normal-tension glaucoma (NTG) patients. The static central visual field by the Humphrey field analyzer, diurnal variation of intraocular pressure (diurnal IOP), blood flow velocity of the ophthalmic artery by color Doppler imaging, blood flow volume of digital tissue by laser flowmetry, and systemic blood pressure (BP) were measured after rinsing out the anti-glaucoma drug for one month. Mean deviation (MD) calculated by the Humphrey STATPAC program as an index of visual field defect, was correlated to the Pourcelot index (RI) of ophthalmic arterial blood flow and magnitude of diurnal IOP. In multiple regression analysis, the multiple correlation coefficient was 0.79 and the coefficient of determination was 0.62. RI, systolic BP, magnitude of diurnal IOP, and the refraction and mean of diurnal IOP were used in the multiple correlation model as factors significantly related to MD. These results suggest that both IOP and some clinical factors may contribute to the visual field defects of NTG.

Aged↗
PubMed1995

[The time required topical carbonic anhydrase inhibitor (MK-507) to take effect on intraocular pressure of normal human eyes].

The effective time course of a topical carbonic anhydrase inhibitor, MK-507, on intraocular pressure (IOP) was studied in 6 normal volunteers. As a baseline study, IOP was determined and aqueous protein concentration was determined by laser flare photometry every half hour for 5 hours with the instillation of a placebo. Then, an examination with the same time course was performed on the same subjects with the instillation of 1% MK-507 or oral administration of acetazolamide at a dose of 250 mg. MK-507 lowered IOP 30 minutes after the instillation, and showed a significant reduction of IOP at 1 hour. Aqueous protein concentration increased significantly 30 minutes after the MK-507 instillation. Acetazolamide lowered IOP 30 minutes after the administration, and showed a significant reduction of IOP at one hour. Aqueous protein concentration increased significantly one hour after the acetazolamide administration. Corneal thickness, anterior chamber depth, anterior chamber volume, and serum protein concentration were not significantly changed by the drug treatment. These results suggest that the inhibition of aqueous humor production causes the rapid reduction of IOP seen in the use of MK-507 as well as acetazolamide.

Administration, Topical↗
PubMed1995

[Porphyria cutanea tarda accompanying hepatitis C].

Porphyria cutanea tarda (PCT) is due to reduced activity of the enzyme uroporphyrinogen decarboxylase in hepatocyte. Hepatic dysfunction is found in almost all cases of PCT. Recently, high prevalence of hepatitis C virus (HCV) infection in patients with PCT was reported in Europe. Is HCV infection a trigger of PCT? Several cases of PCT associated with hepatitis C were reported in Japan. The frequency of anti-HCV increased with the severity of liver histology. These findings implicate HCV in the etiology of PCT-associated liver disease. Treatment with interferon should be considered for PCT with HCV infection.

Alcohol Drinking↗
PubMed1995

[A case of primary pulmonary hemangiopericytoma recurred locally 10 years after the first surgery].

Hemangiopericytoma is a rare tumor of vascular origin. This tumor has a malignant potential and often recurs or metastasize. A case of primary pulmonary hemangiopericytoma which recurred locally 10 years after the first surgery is presented. The histological appearance of the tumor had some findings of malignant potential in both of the primary and recurrent lesions. We discussed on malignant potential of this tumor in the number of mitotic figures, cellular atipia, and DNA ploidy pattern.

Female↗
PubMed1995

Pharmacokinetic study of trimethadione and its metabolite in blood, liver and brain by microdialysis in conscious, unrestrained rats.

A microdialysis method has been developed in the past two decades to determine levels of drug and endogenous compounds in several organs under physiological conditions. In this study, we determined the pharmacokinetics of the model drug, trimethadione (TMO), and its only metabolite, dimethadione (DMO), in liver, blood and brain by the microdialysis method in freely-moving rats. Sampling times were extended up to 24 hours. The construction of a newly developed microdialysis probe for liver and blood is described. The elimination patterns of TMO in liver, blood and brain dialyzates were almost identical and the calculated t1/2 was approximately 3 hr in each sample. However, in brain, tmax was delayed compared with the others while the relative concentration of DMO (AUC0-24h) was lower in brain compared with liver and blood. These studies suggest that this concurrent and successive microdialysis sampling method will not only be a useful tool for pharmacokinetic and drug metabolism studies in the organs of small animals but will also decrease the number of experimental animals needed for a study.

Animals↗
PubMed1995

[Increase in extracellular levels of serotonin and amino acids in the rat brain following cyanide-induced energy failure].

We studied the effects of ATP depletion on neurotransmitter release in the rat brain using the microdialysis method. Ringer's solution containing 2 mM sodium cyanide (NaCN) was perfused into the hippocampus and striatum for 60 min via a microdialysis probe, and changes in serotonin (5-HT) and amino acids (glutamate, aspartate and taurine) levels in dialysates were investigated. NaCN perfusion induced a transient 3.9-fold increase in 5-HT levels in the hippocampal dialysate. Amino acid levels in dialysates also increased during NaCN perfusion, but differently in the striatum and hippocampus (glutamate: 1.3- and 2.4-fold, taurine: 2.3- and 1.3-fold, respectively). Perfusion of Ca(2+)-free Ringer's solution remarkably suppressed the NaCN-induced increase in 5-HT but not the increases in amino acid levels. Depolarization by 100 mM KCl perfusion could induce increases in 5-HT and amino acids in dialysates at 3 hr after NaCN perfusion similarly with that of control. These findings indicate that the sensitivity of nerve terminals to energy failure are different between neurons containing different neurotransmitters and also between brain regions, and suggest that this regionally different sensitivity of amino acid neurons might be involved in the underlying mechanism of the localized vulnerability to transient ischemia.

Adenosine Triphosphate↗
PubMed1995

[Hypersensitivity pneumonitis induced by dust from an automatic bed cleaner].

A 49-year-old woman used an automatic bed cleaner on October 18, 1990. Eight hours later, she was admitted to a hospital complaining of coughing and fever. The chest X-ray film showed small granular shadows in both lower lung fields. After a few days of antibiotic therapy, these symptoms had disappeared. She used the bed cleaner again on the afternoon of November 15, 1990. The next day, she was admitted to our hospital because of coughing and fever. An environmental provocation test with the bed cleaner induced the same symptoms. Dust from the bed cleaner stimulated her lymphocytes. Hypersensitivity pneumonitis from the dust of a bed cleaner was diagnosed.

Allergens↗
PubMed1995

[Myocardial structural proteins in cor pulmonale. Analysis by two-dimensional electrophoresis].

Changes in cardiac structural proteins caused by cor pulmonale were studied with two-dimensional electrophoresis. Sprague-Dawley rats were exposed to an oxygen-poor gas mixture (10% O2/90% N2) for three weeks. These rats (the hypoxic group) were compared to a control group that was kept in room air. Hemoglobin, hematocrit, and right ventricular systolic pressure were greater in the hypoxic group than in the control group. After the third week, desmin content of both ventricular muscles had increased in the hypoxic group, and was significantly greater in the hypoxic group than in the control group. The contents of other cardiac structural proteins did not change. These data suggest that increases in desmin are caused by adaptation of the myocardium to pressure overload associated with pulmonary hypertension. However, increases in the desmin content of the left ventricular muscle might be caused by volume overload, humoral factors, or might be a direct effect of hypoxemia.

Animals↗
PubMed1995

[Thoracoscopic treatment of a giant bulla: a case report].

A 38-year-old man was admitted to our hospital because of left giant bulla and pneumothorax. His chest X-rays and CT scan showed giant bulla of the left upper lobe and left pneumothorax. We performed bullectomy using the ENDOPATH ENDO LINEAR CUTTER 60 mm and 35 mm disporsable surgical stapler under thoracoscopic guidance. Clipping with end-clips and fibrin glue were effective for miner air leakage. There were no complications such as prolonged air leakage or incomplete lung re-expansion. His post operative couse was uneventful and he was discharged from the hospital on the 11th post operative day. When performed along with mini-thoracotomy, thoracoscopic operation is useful in treating patients with giant bulla.

Adult↗
PubMed1995

[Transformation into chronic myelomonocytic leukemia in a patient with primary myelofibrosis associated with severe hypoplasia: report of an autopsy case].

A 70-year-old male was admitted because of anemia in September 1989, and primary myelofibrosis was diagnosed based on the presence of leukoerythroblastosis, a normal chromosomal analysis and pathological findings of fibrosis in bone marrow. Although he was anemic, he did not require any treatment for two years. Then his hematological status deteriorated to severe pancytopenia, and the marrow biopsy revealed marked hypoplasia with fatty replacement and scattered fibrosis. He was treated with metenolon without success and frequent transfusion of packed red cell was required. This hypoplastic status continued for seven months. In May 1992 his WBC count increased gradually with monocytosis. The marrow was filled with various stages of monocytes, with almost no fibrosis remaining. The chromosomal analysis was repeated but disclosed no abnormalities, consistent with the negative result of BCR-ABL rearrangement investigated by the RT-PCR method. One month later, when the patient died of multiple cerebral bleeding and infection, the leukocyte count exceed 90,000/microliters. It is known that major causes of death for patients with primary myelofibrosis are infection, bleeding, cardiac trouble and transformation to leukemia. We describe a case of myelofibrosis who developed to chronic myelomonocytic leukemia following severe aplastic phase.

Aged↗
PubMed1995

[Effects of preoperatively administered flurbiprofen axetil on the action of inhaled anesthesia and postoperative pain].

Flurbiprofen axetil (FP) was evaluated in a randomized study relative to placebo in 26 patients undergoing endonasal ethmoidectomy. The FP group (n = 13) was administrated 1 mg.kg-1 FP 15 minutes before operation during a half hour. Likewise, the control group (n = 13) received intravenous NaCl 0.9%. Concentration and the quantity consumed of sevoflurane, perioperative body temperature, postoperative pain and on-demand dicrofenac sodium consumption were measured. No significant differences were observed concerning concentration and the quantity consumed of sevoflurane. Body temperature of the FP group fell significantly before infusion. The FP group showed lower pain scores and required less dicrofenac sodium than the control group (P < 0.05). This study suggests that preoperative FP infusion relieves postoperative pain, but does not affect the action of the inhalation anesthetic.

Adult↗