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H Sato

Publications and source records attributed to H Sato.

At least 415 records · Page 23Linked to original sources
PubMed2000

Decrease of glucose utilization rate in the spinal cord of experimental 2,5-hexanedione poisoning rats: application of microdetermination technique.

To examine the effects of 2,5-hexanedione (HD) on the glucose metabolism in the spinal cord, glucose utilization rate (GUR) and distribution volume of glucose (DV) were measured in the white matter and anterior horn of the spinal cord in 8 rats exposed to HD for 4 weeks and in 10 control rats. The GUR and DV were determined by the quantitative microdetermination method using non-tracer 2-deoxyglucose based on the three-compartments model of Sokoloff. GURs in the white matter and anterior horn and DV in the anterior horn in the HD-exposed rats were significantly lower than those in the control rats. In the multiple regression analysis, GUR in the white matter of HD-exposed rats was significantly related to blood HD concentration. It is suggested that the decrease of GUR in the white matter is a major effect of HD in the spinal cord.

Administration, Oral↗
PubMed2000

Circadian rhythms of seven heavy metals in plasma, erythrocytes and urine in men: observation in metal workers.

To elucidate circadian rhythms (variation within a day) of 7 toxic or essential metals in plasma and erythrocytes in relation to the rhythms in urine in men, 19 male metal foundry workers were examined; they were exposed to lead (Pb), zinc (Zn) and copper (Cu) occupationally but separated from the exposure during the study. Circadian rhythms were found for plasma concentration of Pb, cadmium (Cd), Zn, Cu and chromium (Cr) in the workers. Circadian rhythms were also found for Pb, inorganic mercury (Hg), Zn and Cr in erythrocytes and for all metals except Zn in urine. Both the plasma and urinary levels of Pb, Cd, Cu and Cr together with urinary excretion of Mn and creatinine tended to decrease during night hours; both the erythrocyte and urinary levels of Hg together with both the plasma and erythrocyte levels of Zn tended to increase during morning hours. The results of profile analysis suggested that the circadian rhythm of Pb in urine was affected more strongly by its plasma and erythrocyte rhythms than by the rhythm of creatinine in urine, i.e. the rhythm of glomerular filtration; the urinary rhythms of Cd, Cr, and Mn were affected more by the creatinine rhythm; and the urinary rhythm of Cu was affected by both its plasma and creatinine rhythms. On the other hand, the urinary rhythm of Hg was assumed to be independent of the creatinine rhythm and be affected by its erythrocyte rhythm. The present study suggested that different biological limit values might be needed for different hours of the day especially for shift workers who are exposed to various heavy metals. Instead, further studies should be conducted to find the adjustment methods by which no circadian rhythms are discerned.

Adult↗
PubMed2000

Alteration of glucose metabolism in the spinal cord of experimental lead poisoning rats: microdetermination of glucose utilization rate and distribution volume.

To examine the effects of lead on glucose metabolism in the spinal cord, glucose utilization rate (GUR) and distribution volume of glucose (DV) in the anterior horn and white matter were determined in 9 rats exposed to lead for 4 weeks and 10 control rats. The GUR and DV were determined by the quantitative microdetermination method using non-tracer amount of 2-deoxyglucose based on the three-compartments model of Sokoloff. The GUR and DV in the anterior horn in the lead-exposed rats were significantly lower than those in the controls. It is thus suggested that glucose metabolism, as measured by the GUR and DV, in the anterior horn is inhibited by lead; the anterior horn cells seem sensitive to lead neurotoxicity.

Animals↗
PubMed2000

Methionine imbalance and toxicity in calves.

The occurrence of methionine imbalance and toxicity was examined using 70- and 100-kg Holstein bull calves. The animals had been trained to maintain reflex closure of the reticular groove after weaning at 5 wk of age, and Trials 1 (n = 30) and 2 (n = 24) were conducted on animals at 7 and 12 wk of age, respectively. Calves received a corn-soybean meal diet in Trial 1 and a corn-corn gluten meal diet in Trial 2. In Trial 1, postruminal administration of 6 g of DL-methionine/d increased ADG, feed intake, gain/feed, and N retention compared with a control group receiving N-free supplement. However, the administration of 12 g of DL-methionine/d did not improve these variables, whereas both 18 and 24 g/d resulted in BW loss and decreased gain/feed and N utilization efficiency. In Trial 2, postruminal administration of 16 g/d of L-lysine from L-lysine monohydrochloride increased ADG, gain/feed, and N utilization efficiency compared with a control group receiving a N-free supplement. The administration of 8 g of DL-methionine/d in addition to L-lysine did not exert an adverse effect on these variables. However, the additional supplementation of 16 and 24 g of DLmethionine/d negated the improvement, whereas 32 g/d resulted in BW loss and decreased gain/feed and N utilization efficiency. These results showed that a methionine imbalance and toxicity occurred in calves with even a modest excess of DL-methionine, and 70-kg calves were more susceptible to methionine toxicity than 100-kg calves. Plasma concentrations of branched-chain amino acids and phenylalanine linearly decreased with increasing amounts of additional DL-methionine from 0 to 32 g/d in Trial 2. However, such a decrease occurred mainly within the range from 0 to 12 g/d in Trial 1. This decrease was suggested to occur in relation to methionine metabolism via the transsulfuration pathway.

Amino Acids↗
PubMed2000

Influence of abomasal infusion of high levels of lysine or methionine, or both, on ruminal fermentation, eating behavior, and performance of lactating dairy cows.

Four multiparous late-lactation Holstein cows were fed a basal ration designed to be co-limiting in intestinally absorbable supplies of methionine and lysine. Cows were supplemented with no amino acids, lysine by abomasal infusion to 140% of the calculated intestinally absorbable requirement, methionine by abomasal infusion to 140% of requirement, or both amino acids in a 4 x 4 Latin square design with 28-d periods. Unsupplemented cows consumed 23.8 kg/d of dry matter and produced 36.9 kg/d of milk containing 3.70% fat, 3.22% protein, and 4.82% lactose. Cows ate less dry matter and produced less milk and milk lactose, and tended (P = .06 or .08) to produce less milk protein when abomasally infused with methionine alone or together with lysine. Infusion of lysine alone resulted in production values numerically between those of unsupplemented cows and those cows supplemented with methionine alone or together with lysine. Evaluation of the results with two metabolic models of dairy cows indicated that performance of unsupplemented cows may have been limited by delivery of metabolizable or digestible protein, or intestinally absorbable lysine, isoleucine, or histidine, depending on the metabolic model used to evaluate animal performance. Regardless, results are consistent with those using nonruminant species, which have shown that imbalanced profiles of intestinally absorbable amino acids are associated with reduced dry matter intake and animal performance. Results also show that negative effects on performance of lactating dairy cows can occur if methionine is supplied at levels substantially in excess of calculated intestinally absorbable requirements, either alone or together with lysine.

Abomasum↗
PubMed2000

[Long-term prognosis after reperfusion therapy for acute myocardial infarction in elderly patients].

Although it has been well demonstrated that TIMI grade 3 flow is associated with improved survival after acute myocardial infarction in non-elderly patients, its implication in elderly patients has not been clarified. To assess this issue, 1,115 patients with acute myocardial infarction who underwent coronary angiography within 24 hours after the onset of chest pain were studied: there were 131 elderly patients (age > or = 75 years) and 984 non-elderly patients (age < 75 years). Follow-up was achieved for 1,092 patients (98%). Elderly patients were associated with more female, Killip class > or = 2, 3 vessel disease and non-smokers. Although modality of reperfusion therapy was not different, final TIMI flow grade was less frequently obtained in elderly patients (53% vs 65%, p = 0.005). Elderly patients were associated with higher in-hospital mortality (25% vs 9%, p < 0.001) and lower 10 years cardiac death free rate (p < 0.001). Cox proportional hazards model showed that final TIMI flow grade 3 was an independent predictor of 10 years cardiac death free in elderly patients (odds ratio (OR) = 0.39, 95% confidence interval (CI) = 0.20-0.74, p = 0.004) as well as non-elderly patients (OR = 0.41, 95% CI = 0.29-0.58, p < 0.001). In conclusion, our data suggest that final TIMI grade 3 flow is an important determinant to improve short- and long-term survival after acute myocardial infarction in elderly patients as well as in non-elderly patients.

Age Factors↗
PubMed2000

Tumor regression by inductive hyperthermia combined with hepatic embolization using dextran magnetite-incorporated microspheres in rats.

We formulated a novel preparation of microspheres incorporating dextran magnetite complex (DM-MS), which enable magnetic field-induced heating for the induction of hyperthermia. Using a 500 kHz magnetic field combined with arteriolar embolization of DM-MS, inductive hyperthermia was performed for the treatment of liver tumors in rats. Three days after treatment, the percentage increase of tumor volume in the embolo-hyperthermia, embolization alone, and control groups were 28%, 124%, and 385%, respectively, with the embolo-hyperthermia group differing significantly from the remaining groups. This study demonstrated the feasibility of combining embolization of DM-MS with hyperthermia as an antitumor therapy.

Animals↗
PubMed2000

Canal and otolith inputs to single vestibular neurons in cats.

Convergence of both afferents from the PC and saccular macula, and those from the PC and utricular macula on single vestibular neurons was noted by use of intercellular recording from vestibular neurons. Vestibular neurons were classified VO neurons (vestibulo-ocular proper neurons), VOS (Vestibulo-oculo-spinal neurons sending axon collaterals both to the extraocular motoneuron pools and to the spinal cord), VS neurons (vestibulospinal proper neurons) and V neurons (vestibular neurons without axons to the oculomotor nuclei or the spinal cord) on the basis of whether or not they responded antidromically to stimulation of the oculomotor nuclei and the spinal cord. Of the total 143 vestibular neurons recorded in the series of experiments on convergence of the PC and saccular afferents, 47 neurons (33%) were received inputs from both the PC and saccular nerves. Twenty-six of the 47 convergent neurons were identified as having the nature of VS neurons. Half (13/26) of those were activated monosynaptically from both the PC and saccular nerves. Only one saccular-activated neuron without PC inputs sent an axon to the oculomotor nuclei. In the other series of experiments on the convergence of the PC and utricular afferents, 41 (37%) of 111 vestibular neurons were proved to converge on inputs from both nerves. The majority (35/41) of the neurons received monosynaptic inputs from the PC nerve and polysynaptic EPSP-IPSP sequences from the utricular nerve, or vice versa. The ratio of PC-otolith convergent neurons among utricular-activated neurons (41/54, 76%) was higher than that among saccular activated neurons (47/88, 53%). The percentage of utricular alone neurons without PC inputs (13/111, 12%) was less than that of the saccular alone without PC inputs (41/145, 28%). In conclusion, the convergence of canal and otolith inputs likely contribute mainly to vestibulospinal reflexes including the vestibulocollic reflex, by sending inputs to the neck and other muscles during head inclination which creates the combined stimuli of angular and linear acceleration.

Animals↗
PubMed2000

Elevation of antibody against Epstein-Barr virus genes BRLF1 and BZLF1 in nasopharyngeal carcinoma.

PURPOSE: Epstein-Barr virus immediate early genes BZLF1 and BRLF1 encode the Z and R proteins respectively. Elevation of the anti-Z immunoglobulin (Ig) antibody titer is a common feature of nasopharyngeal carcinoma (NPC) in areas where the disease endemic, whereas R levels have not been examined. This study was performed to analyze antibody titers against Z and R in Japan. METHODS: Sera from 14 patients with newly diagnosed NPC, 7 with NPC in complete remission, 15 with head and neck squamous cell carcinoma (HNSCC), and 31 controls were evaluated by enzyme-linked immunosorbent assay (ELISA) and immunoblotting. RESULTS: Both anti-Z and anti-R Ig were significantly increased in sera from patients with NPC compared with those in remission, those with HNSCC, and controls (Z, P = 0.0016, = 0.0344, = 0.0002; R, P = 0.0015, = 0.0004, <0.0001 respectively). By immunoblot analysis, anti-Z and anti-R Ig were detected in 9 of 9 cases of NPC, 1 of 3 cases NPC in remission, and 2 of 13 cases of HNSCC. Anti-Z and anti-R antibody titers were nine times higher in NPC than in other groups. None of 15 control cases showed positive reactivity against either Z or R. CONCLUSION: Coupled evaluation of anti-Z and anti-R Ig by ELISA might be a useful system for screening NPC.

Carcinoma, Squamous Cell↗
PubMed2000

[Clinical experience using percutaneous cardiopulmonary support system for stent replacement].

Three cases of tracheal or mein bronchus stenoses were treated using percutaneous cardiopulmonary support system (PCPS). Case 1 was a 63-year-old male admitted for dyspnea due to stenotic trachea with primary lung cancer invasion. YAG-laser operation and Dynamic stent was inserted to the trachea using PCPS. Case 2 was a 74-year-old male admitted for dyspnea due to stenotic right mein bronchus with primary lung cancer invasion. Dumon Y stent was inserted to the right mein bronchus using PCPS. Case 3 was 57-year-old male admitted for dyspnea due to stenotic trachea and occluded left mein bronchus with ischemic change after primary esophageal cancer operation. Dynamic stent was inserted to the trachea and left mein bronchus using PCPS. Tracheal and mein bronchus stenoses the trachea of all was dilated after placement of stent. These three cases had no complications during or after these treatment. These results indicated that using PCPS was a very useful, powerful and satisfactory method in the treatment of tracheal or mein bronchus stenoses during the lack of lung ventilation.

Aged↗
PubMed2000

[A randomized trial of conventional dose vs reduced dose in BHAC-DM therapy for acute myelogenous leukemia in elderly patients].

Twenty-nine patients aged 60-75 years with newly diagnosed acute myelogenous leukemia (AML) were randomized to receive BHAC-DM either at a reduced dose (S-1 group, n = 13; BHAC 150 mg/m2 1-7 day, DNR 30 mg/m2 1-3 day, 6MP 70 mg/m2 1-7 day) or the conventional dose (S-2 group, n = 16; BHAC 200 mg/m2 1-7 day, DNR 40 mg/m2 1-3 day, 6MP 70 mg/m2 1-7 day). On day 7, patients were given therapy for 2 more days if the ratio of blasts in their bone marrow was more than 15%. Granulocyte-colony stimulating factor was injected when the leukocyte count decreased below 1,000/microliter. The rates of complete remission were 46.2% in the S-1 group and 43.8% in the S-2 group. No significant differences in response distinguished the 2 groups. The mortality rate during myelosuppression was 1/13 in the S-1 group and 1/16 in the S-2 group. The rate of treatment-related death was 10.1% for all patients. Grade-4 adverse effects were not seen in any of the patients. We concluded that the conventional dose of BHAC-DM was as acceptable as the reduced dose in elderly patients with AML.

Aged↗
PubMed2000

[Evaluation of hemodynamics in cerebral infarction using MRI with FAIR sequence].

In comparison with 99mTc-ECD SPECT, the usefulness for evaluation of cerebral blood flow by the perfusion images using MRI with FAIR sequence was studied in ischemic stroke patients. Among 27 cases, 15 patients showed lacunar infarctions and 12 patients showed cortical infarctions determined by T2 weighted MR images. FAIR images were obtained as single images at the slice position running through the basal ganglia or corona radiata. The inversion times(TI) were varied, ranging from 800 to 1,400 msec. In 15 patients without definite low perfusions in the SPECT study, FAIR images showed sequentially proxymal arterial branches in early phase and distal arterial branches or capillary beds in the cortical tissues in a late phase as the TI was elongated. Nine of the 12 patients with low cerebral perfusions in the SPECT study showed perfusion defects in FAIR imaging. Five of the 12 patients with a small low cerebral perfusion area in the SPECT study showed a delay of the depiction of cortical arteries along with TI elongation. In 3 patients, ischemic lesions demonstrated by the SPECT study was not shown in the MRI study because of motion artifacts. In conclusion, FAIR imagings are considered to be useful in the evaluation of cerebral flow dynamics in the ischemic stroke patients.

Aged↗
PubMed2000

[Tuberculin survey of university students and postgraduates in 1998].

As no recent report has been made concerning the tuberculin survey of healthy young adults in Japan, we checked all the Tohoku University undergraduate and postgraduate students by tuberculin test for the assessment of TB-situation in 1998. The sample included 5,517 students and postgraduates (3,888 males and 1,629 females; 31% of all subjects to be tested) who were evaluated on the basis of the redness of the skin test. The average age of the subjects was 22.3 +/- 3.1 years old (ranging from 18 to 51). As a result of this survey, 5,032 (91.2%) were positive and 485 (8.8%) were negative, and the average diameter of redness was 28.5 +/- 19.2 mm. Non-reactors received an additional BCG vaccination. Subjects showing strongly-positive (20.1%) results were rechecked by physical examination and chest X-ray, and none was found to require treatment by anti-TB drugs. Our findings also demonstrated that the diameter of redness was larger in the group previously BCG-vaccinated than in the group who had not received BCG vaccination previously (p < 0.01).

Adult↗
PubMed2000

[Recent advances in the surgical management of esophageal achalasia: modified Girard method and laparoscopic approach].

The standard surgical treatment for esophageal achalasia consists of contraction of the lower esophageal sphincter combined with antireflux repair. This paper describes the techniques of the modified Girard method with a laparoscopic approach. The modified Girard method consists of a long esophagomyotomy, the placement of horizontal transverse sutures to prevent restricture due to reflex, and fundopexy for antireflex repair. We have recently used a laparoscopic approach with the modified Girard method in 10 patients with esophageal achalasia. A total of five trocars were required for the long myotomy in the lower esophagus and repair of the esophagogastric junction. A myotomy of approximately 10-12 cm was made along the lower esophagus and cardia lesion using an electric J-hook. Than transverse sutures were placed on each side of the lower myotomy and the gastric fundus was covered with the upper myotomy with several sutures to diaphlagm and each side of the myotomy lene. Excellent results were achieved, and the patients recovered from surgery more quickly compared with those undergoing an open procedure. However, postoperative manometric findings did not differ between patients who underwent the laparoscopic and open procedures.

Adult↗
PubMed2000

[A case of pulmonary adenocarcinoma of arising from the wall of a giant bulla which disappeared spontaneously].

In a 53-year-old man, giant bulla was detected on the left side on chest X-ray and mass shadow was demonstrated near the bullae (20 x 10 mm). CT scan did not show a mass shadow and the shadow was diagnosed as scar formed by the bulla wall. Three months later, the bulla had disappeared spontaneously, but an abnormal shadow at the apex of left lung was pointed out. Chest CT findings suggested lung cancer arising from the wall of the collapsed giant bullae and partial resection of the left upper lobe was performed. The postoperative pathological diagnosis was moderately differentiated adenocarcicoma (12 x 5 x 5 mm) arising from pulmonary bullae. It must be noted that occult cancer may exsist at the wall of giant bullae, the surgical procedure involving complete resection of the bullae wall must be selected.

Adenocarcinoma↗
PubMed2000

In vitro and in vivo inhibition of activation induced T cell apoptosis by bucillamine.

OBJECTIVE: To investigate the mechanism of autoimmune phenomena, occasionally seen in patients with rheumatoid arthritis treated with bucillamine (BUC) and D-penicillamine (D-Pen), by evaluating their effects on apoptosis of T cells induced by T cell receptor activation or dexamethasone. METHODS: In vitro apoptosis was induced in a T cell hybridoma (SSP3.7) and a B cell line (WEHI 231) by activation of respective receptors or dexamethasone, in the presence or absence of BUC or D-Pen. In vivo apoptosis was induced in BALB/c mice by staphylococcal enterotoxin B (SEB), with or without BUC or D-Pen, and thymocytes were examined for it by FACS. RESULTS: Stimulation with anti-CD3 and dexamethasone induced apoptosis in 72% and 71% of SSP3.7 cells, respectively. However, only 16% of SSP3.7 cells became apoptotic by anti-CD3 when BUC was added to the culture media. By contrast, 80% of SSP3.7 cells became apoptotic when stimulated by dexamethasone, even in the presence of BUC. BUC did not affect apoptosis of WEHI 231 cells induced by anti-IgM. Although SA981 (a metabolite of BUC) inhibited apoptosis of SSP3.7 cells induced by anti-CD3, D-Pen did not. BUC, SA981, or D-Pen did not significantly influence the level of interleukin 2 secretion stimulated by anti-CD3. In contrast, both BUC and D-Pen inhibited apoptosis of Vbeta8+ thymocytes induced in vivo by SEB superantigen. Neither BUC nor D-Pen significantly changed the number of CD4+CD8+ thymocytes in BALB/c mice injected with dexamethasone. CONCLUSION: BUC decreased, while D-Pen did not, the apoptosis of T cells stimulated by anti-CD3 in vitro, although they both inhibited the deletion of immature thymocytes reactive with SEB in vivo. This may explain autoimmune phenomena sometimes seen during the treatment of rheumatic patients with these drugs.

Animals↗