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M Aoki

Publications and source records attributed to M Aoki.

At least 577 records · Page 32Linked to original sources
PubMed1993

[The limits for modified Fontan operations with AV valve regurgitation--the effect of AV valve regurgitation on the Fontan operation for single ventricle].

We performed a modified Fontan operation on 14 patients of single ventricle with AV valve regurgitation (single right ventricle: SRV 8, single left ventricle: SLV 6) until 1990. During the same period, 41 patients of single ventricle without AV valve regurgitation underwent the modified Fontan operation. To evaluate the effect of AV valve regurgitation on the Fontan operation, operative mortality, ventricular and pulmonary functions were compared between two groups. No significant differences were observed in operative mortality (7% vs 12%). There were also no significant differences of post-operative cardiac index (mean 2.6 L/min/m2 vs 2.6 L/min/m2), pulmonary vascular resistance (mean 2.3 U.m2 vs 2.2 U.m2) and preoperative ejection fraction (mean 54% vs 62%) between two groups. Therefore, the hemodynamic status of single ventricle following the Fontan operation remained almost unchanged irrespective of the presence of AV valve regurgitation. This suggested that AV valve regurgitation was not itself a contraindication of the Fontan operation, if the correct indices and time for operation were selected.

Heart Atria↗
PubMed1993

[Characteristics of tuberculosis in Japan compared with those in other developed countries].

To clarify the characteristics of the tuberculosis situation in Japan, it was analysed in comparison with those in other developed countries. The results are summarized as follows: 1. The tuberculosis epidemic peaked at the end of 1910s in Eastern Japan, and in the 1940s in Western Japan. It is estimated that the annual risk of tuberculosis infection was 4% or more until the end of the World War II. Tuberculosis has spread much later and was much more prevalent up through the 1940s in Japan than in other developed countries. 2. A modern tuberculosis control programme including active case-finding, isolation of infectious cases, charge free medication and BCG vaccination was launched in 1951, and in 1961 an effective case-holding system was established. Tuberculosis incidence decreased rapidly thereafter. As the rate of decrease was almost the same as that of the Inuit (Eskimo) (Fig. 1), one might say that Japan is one of the countries where tuberculosis incidence decreased most rapidly. 3. Incidence of tuberculosis in children is 2.1 per 100,000 in 1991 which is lower than that of the U.S.A. (3.1 per 100,000). 4. Incidence of tuberculosis among the aged is much higher than that of other developed countries as shown in Fig. 3. Of course, this is mainly caused by the fact that a higher percentage of Japanese aged 55 years or more was infected with tubercle bacilli in the past.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Recovery of cerebral blood flow and energy state in piglets after hypothermic circulatory arrest versus recovery after low-flow bypass.

A miniature piglet model that replicates clinical hypothermic (14 degrees C nasopharyngeal) circulatory arrest and low-flow (50 ml/kg per minute) bypass was used to study carotid blood flow with electromagnetic flow probe, cerebral blood flow by microsphere injection, cerebral metabolic rate by arteriovenous oxygen and glucose extractions, lactate production by cerebral arteriovenous difference, and cerebral edema. Data from five animals that underwent circulatory arrest and five animals that underwent low-flow bypass (aged 28.8 +/- 0.4 [mean +/- standard error of the mean] days) were analyzed. The duration of circulatory arrest and low-flow bypass was 1 hour. In a parallel study with the same animal model, phosphorus 31 magnetic resonance spectroscopy was used to assess cerebral phosphocreatine, nucleoside triphosphate (adenosine triphosphate), and intracellular pH. Five animals (aged 31.8 +/- 1.1 days) underwent circulatory arrest, and five underwent low-flow bypass. A brief phase of hyperemic carotid blood flow was seen immediately after the onset of reperfusion in the circulatory arrest group but not in the low-flow group. In the circulatory arrest and low-flow bypass groups, cerebral blood flow (percentage of baseline 71.2% +/- 8.3% and 69.1% +/- 5.8%, respectively), cerebral oxygen consumption (45.6% +/- 10.0%, 44.5% +/- 7.6%), and cerebral glucose consumption (31.5% +/- 30.7%, 83.5% +/- 24.2%) remained depressed after 45 minutes of reperfusion and rewarming to normothermia. However, after 3 more hours of pulsatile normothermic reperfusion, cerebral oxygen consumption and cerebral glucose consumption had returned to baseline. Phosphocreatine, adenosine triphosphate, and pH were maintained at or above baseline levels throughout low-flow bypass and throughout 3 hours of normothermic reperfusion. In contrast, both phosphocreatine and adenosine triphosphate became undetectable 32 +/- 3.7 minutes after onset of circulatory arrest. During and early after circulatory arrest, pH decreased to a minimum of 6.506 +/- 0.129 at 40 minutes after reperfusion. After 3 hours of normothermic reperfusion, phosphocreatine and adenosine triphosphate recovered to 98.6% +/- 9.0% and 90.1% +/- 13.5% of baseline, respectively, and pH was 7.087 +/- 0.051, similar to baseline (7.1755 +/- 0.041). In the low-flow bypass group, the disparity between the depressed level of cerebral oxygen consumption and normal high-energy phosphate levels may reflect incomplete cerebral rewarming or decreased energy consumption. In the circulatory arrest group, the parallel recovery of oxygen consumption and high-energy phosphates eventually achieving baseline levels suggests that the degree of hypothermia used provides adequate protection for acute cerebral recovery after 1 hour of circulatory arrest.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenosine Triphosphate↗
PubMed1993

[Surgical therapy with adjuvant radiotherapy of thymoma: results of 104 cases].

One hundred and four cases of thymomas were treated between 1967 and 1991 at the Chest Disease Institute, Kyoto University. Forty-two cases were clinical stage I, 12 cases were stage II, 42 cases were stage III and 8 cases were stage IV. Nineteen patients had MG, 17 patients had SVC syndrome. Ninety-six cases were surgically resected combined with radiation therapy. Overall survival was 77.9% at 5 years and 62.5% at 10 years. The survival of 62 cases of invasive thymoma was 77.5% at 5 years and 54.8% at 10 years. We've got better prognosis when total or subtotal resection of invasive thymoma could be accomplished, i.e. 88.8% at 5 years and 72.6% at 10 years.

Female↗
PubMed1993

Effect of calcium and preischemic hypothermia on recovery of myocardial function after cardioplegic ischemia in neonatal lambs.

Hypothermia has been reported to increase intracellular ionized calcium, which may aggravate injury resulting from ischemia and reperfusion. The effects of plasma ionized calcium concentration ([Ca2+]) during hypothermic perfusion on recovery after 2 hours of cold cardioplegic ischemia were evaluated in 32 isolated, blood-perfused neonatal lamb hearts. Three groups of hearts (B, C, and D) were perfusion-cooled for 10 minutes to a myocardial temperature of 17 degrees C and then arrested with St. Thomas' Hospital cardioplegic solution. Group A had 10 minutes of normothermic perfusion before cardioplegia. Group B had cooling with normal [Ca2+]. Group C had citrate added as cooling was started to lower [Ca2+] (0.26 mmol/L), and it was not normalized until 15 minutes into reperfusion. Group D received citrate plus Ca2+ to give normal [Ca2+] during cooling. Groups B and D showed a significantly reduced recovery (p < 0.05) in left ventricular systolic function (developed pressure and the rate of pressure rise) and diastolic function (stiffness constant) than groups A and C. During preischemic cooling, oxygen consumption per beat and coronary vascular resistance increased significantly in groups B and D, but both oxygen consumption and coronary vascular resistance were significantly lower in group C than in groups B and D so long as [Ca2+] was low. The data show that preischemic hypothermia results in reduced postischemic recovery of function compared with simultaneous induction of cardioplegia and hypothermia. Low [Ca2+] during preischemic hypothermia and early reperfusion offsets this deleterious effect of hypothermia.

Animals↗
PubMed1993

Bronchial circulation after experimental lung transplantation. The effect of long-term administration of prednisolone.

The effect of corticosteroids on bronchial healing after modified left lung transplantation was investigated in pigs. In groups I (n = 6) and II (n = 6), animals received cyclosporine (15 mg/kg per day) and azathioprine (2 mg/kg per day). In group II, prednisolone (1 mg/kg per day) was also administered. Bronchial blood flow was estimated at the donor carina and donor second carina with laser Doppler velocimetry and radioisotopes 7 days postoperatively; macroscopic and microscopic assessments of graft airways were performed. Bronchial blood was calculated relative to the recipient carina. In group II, bronchial blood flow at the donor carina and donor second carina was significantly higher than that of group I. Macroscopic assessment revealed more pronounced ischemic changes in group I (5 of 6 animals) than in group II (2 of 6 animals, p = not significant). Microscopically, airway samples from the donor carina revealed marked destructive changes in five of six animals in group I. In group II, only mild ischemic changes, which were limited to the respiratory epithelium, were seen. We concluded that the administration of prednisolone results in improved bronchial blood flow and decreased bronchial ischemia after lung transplantation.

Animals↗
PubMed1992

Phospholipid metabolism and second messenger system after brain ischemia.

To evaluate possible involvement of phospholipid metabolism and related second messenger systems in the selective neuronal damage after ischemia, we measured changes of polyphosphoinositides (PPIs) and free fatty acids (FFAs) in a model of 5-min or 10-min ischemia and reperfusion in gerbils. The binding activity of 3H-phorbol 12,13-dibutyrate (PDBu) for protein kinase C (PKC) and 3H-inositol 1,4,5-triphosphate (IP3) for IP3 receptors was demonstrated autoradiographically. Induction of 70 KDa heat shock protein (HSP70) mRNA and amyloid precursor protein (APP) mRNA was also examined using Northern blot analysis. In the parietal cortex (an area resistant to transient ischemia), PPIs decreased during ischemia and recovered rapidly after reperfusion. However, recovery did not occur in the hippocampal CA1 area (an area more vulnerable to transient ischemia). In the cortex, arachidonic acid (AA) increased during ischemia and returned to baseline by 7 days after reperfusion; in the CA1 area, the AA level remained elevated even after 7 days of reperfusion. PDBu binding decreased in CA1 cells after 2 days of reperfusion. IP3 binding began to decrease at 5 hr of reperfusion, which is far earlier than either the onset of decreased PDBu binding or the observation of neuronal damage by light microscopy. The induction of HSP70 mRNA occurred, but the induction of APP mRNA did not. Regional differences in the induction of HSP70 mRNA were found; CA1 cells produced less HSP70 mRNA than cortical cells 8 hr after transient ischemia. These results suggest that CA1 cell membranes may not recover after transient ischemic attack, and that the membranes of the endoplasmic reticulum, which have IP3 receptors, may undergo alterations earlier than cytoplasmic membranes. The variable induction of HSP70 mRNA may be related to regional differences in vulnerability in cortical and hippocampal CA1 cells after transient ischemia. Involvement of excitatory neurotransmission in the induction of HSP70 has been suggested. The combined data may support a role for inositol phospholipid metabolism, changes in related second messenger systems, and induction of HSP70 in the excitotoxic mechanism of hippocampal CA1 neuronal damage, death, and repair.

Amyloid beta-Protein Precursor↗
PubMed1992

Phylogenetic relationships of the genera Arthroderma and Nannizzia inferred from mitochondrial DNA analysis.

The phylogenetic relationship of the genera Arthroderma and Nannizzia, was investigated by mitochondrial DNA analysis based on the restriction-fragment-length polymorphisms. Phylogenetic trees made on ten species. A. benhamiae, A. insingulare, A. quadrifidum, A. simii, A. vanbreuseghemii, N. fulva, N. grubyia, N. gypsea, N. incurvata and N. otae showed no definite distinctions between the genera Arthroderma and Nannizzia. These results support the conclusion of Weitzman et al. that the genera Arthroderma and Nannizzia are congeneric.

Ascomycota↗
PubMed1992

Effects of intravenously administered lidocaine on pulmonary vagal afferents and phrenic nerve activity in cats.

The ability of lidocaine to suppress activity of single vagal afferent fiber and that of phrenic nerve was studied in 20 cats anesthetized with pentobarbital. Slowly adapting stretch receptors (SAR, n = 16) and rapidly adapting stretch receptors (RAR, n = 7) were identified by their discharge pattern to pulmonary inflation. Intravenous lidocaine (1 mg.kg(-1) or 2 mg.kg(-1)) produced a suppression of SAR activity but not of RAR activity. Suppression of phrenic nerve activity lasted much longer than that of SAR. These findings indicate that iv lidocaine acts more dominantly on CNS than on peripherals. We conclude that iv lidocaine prevents cough and hemodynamic changes caused by airway manipulation mainly through its action on CNS and not on peripherals (peripheral nerves or their receptor).

Journal Article↗
PubMed1992

Effects of tolbutamide on fructose-2,6-bisphosphate formation and ketogenesis in hepatocytes from diabetic rats.

To assess the extrapancreatic action of sulfonylurea directly in the diabetic, effects of tolbutamide on hepatocyte fructose-2,6-bisphosphate (F-2,6-P2) formation and ketone production were investigated using isolated hepatocytes from streptozotocin (STZ)-induced diabetic rats. The basal level of hepatocyte F-2,6-P2 was significantly higher in diabetic rats within 2 weeks after STZ (40 mg/kg body weight) injection compared with that in the nondiabetic control group. Ultimately, a marked decrease in the F-2,6-P2 level was observed at 4 weeks after STZ administration (10% of the control). Although the addition of tolbutamide further increased the hepatocyte F-2,6-P2 level during the first week after STZ injection, no significant effect was observed after the second week and on from the initial STZ. Treatment of diabetes with insulin restored the stimulatory effect of tolbutamide on the hepatocyte F-2,6-P2 formation. Tolbutamide, independently of insulin treatment, lowered the ketone production of hepatocytes from diabetic rats. The present results indicate that insulin is necessary, in advance, for sulfonylurea to stimulate the liver F-2,6-P2 formation, while tolbutamide inhibition of hepatocyte ketone production is independent of insulin. These results provide further support for the role of sulfonylurea in regulating hepatic energy metabolism in the diabetic.

3-Hydroxybutyric Acid↗
PubMed1992

Some chemical properties of the HCl-methanol extract from the puparial cuticle of Drosophila melanogaster.

1. The HCl-methanol (HCl-MeOH) soluble fraction from the puparial cuticle of yellow, black and ebony of D. melanogaster was hydrolyzed in hydrochloric acid and examined for beta-alanine, ketocatechol, and acetic acid. 2. Between beta-alanine and ketocatechol and between beta-alanine and acetic acid, a quantitatively inverse relationship was found, respectively. The former relationship was further confirmed by the feeding experiment of beta-alanine to black. 3. Of total beta-alanine in the HCl-MeOH extract, the proportion of those having free amino group was 74.8 per cent. 4. All these results indicate that the HCl-MeOH soluble fraction of the puparial cuticle may be useful for investigating the cross-link structure of the cuticle.

Acetates↗
PubMed1992

Isolation of complementary DNAs for heat shock protein (HSP) 70 and heat shock cognate protein (HSC) 70 genes and the expressions in post-ischaemic gerbil brain.

A complementary DNA (cDNA) library was constructed with a plasmid vector from cerebral cortices of gerbils at 8 h of reperfusion after 10 min of bilateral common carotid ligation. After the 3rd screening of this cDNA library with a human genomic DNA probe for HSP70 (pH2.3), 4 cDNA clones were isolated (named pGA3' pGB1' pGD3 and pGE4' respectively). Southern and Northern blot analysis, and partial nucleotide sequence analysis indicated that pGA3 and pGE4 were the HSP70 cDNA clones, and that pGB1 and pGD3 were the HSC70 cDNA clones, which selectively recognized HSP70 or HSC70 mRNA, respectively. HSP70 mRNA is present in a very small amount in normal controls, and is greatly induced after the transient ischaemia. HSC70 mRNA is constitutively expressed in a normal gerbil brain, but is still inducible. In situ hybridization study demonstrated that the HSP70 mRNA was present in a very small amount in the hippocampal pyramidal and dentate granule cells in the sham control, and that the mRNA was greatly induced in the cells of hippocampus, dentate gyrus, medial habenula, ventral thalamic nuclei, caudate putamen, ventromedial and arcuate hypothalamic nuclei, amygdaloid nuclei and cerebral cortex after 8 h of reperfusion. HSC70 mRNA was present in almost the same areas of sham control, and was slightly induced after 8 h of reperfusion. Our results indicate that HSP70 and HSC70 cDNA clones were first isolated from post-ischaemic gerbil brain, and selectively recognize HSP70 or HSC70 mRNA, respectively. A regional difference in the induction of the HSP70 and HSC70 mRNA in post-ischaemic gerbil brain was observed by in situ hybridization.

Animals↗
PubMed1992

Differential expression of heat shock protein 70 gene between the cortex and caudate after transient focal cerebral ischaemia in rats.

In relation to changes of total protein synthesis, induction of 70-kDa heat shock protein (HSP70) mRNA was examined by Northern blot and in situ hybridization after 30 min of transient middle cerebral artery (MCA) occlusion of rats. HSP70 mRNA was not present in the control condition of brain. With reperfusion, the mRNA was greatly induced along with the recovery of total protein synthesis in the cerebral cortex and lateral caudate of the ipsilateral hemisphere. However, the level of the mRNA reached a maximum earlier in the lateral caudate (at 3 h) than in the cortex (at 8 h), and the maximum amount of the mRNA was much smaller in the caudate than in the cortex. Total protein synthesis in the lateral caudate did not completely recover until 7 days. Histological examination showed a severe damage in cells of lateral caudate, while cells in the cortex were almost normal at 7 days. No difference in the brain temperature was observed between the two regions. These results show that the induction of HSP70 mRNA correlates with the recovery of protein synthesis in brain cells after a transient ischaemia, and that the HSP70 gene expression is different at the transcriptional level between the cortical and caudate cells after the transient ischaemia.

Animals↗
PubMed1992

[Clinical efficacy of levofloxacin (LVFX) single-dose therapy in female acute uncomplicated cystitis].

Treatment of infections by the use of antimicrobial agents should be made essentially in a dose close to the minimally required dose. Acute uncomplicated cystitis in female fits as the subject for a single-dose therapy since it is an infection reactive relatively easily to antimicrobial agents. Accordingly, an assessment has been made regarding the therapeutic results of the single-dose therapy in 76 female cases of acute uncomplicated cystitis by the use of LVFX 200 mg which is a new quinolone. The urinary concentration more than MIC90 to Escherichia coli is sustained for about 3 days by this single-dose therapy. As a result of judging the therapeutic results from the reactions of the three clinical findings of pain on micturition, pyuria and bacteriuria, excellent therapeutic results were obtained with effective rates being 100% (76/76) on the day 3, 93.9% (46/49) on the day 7 and 94.4% (34/36) on the day 14. The rate of cystitic symptoms which recurred posed no problem, being 12.5% (5/40) up to three months, as investigated by a questionnaire. As a result of performing close urological examinations such as cystoscopy on six cases with insufficient results or recurrence, we could detect mild underlying conditions which are considered to be intractable factors in the bladder in three cases. From the above results, the single-dose therapy of acute uncomplicated cystitis in the female by LVFX which is a new quinolone was considered to be an excellent therapeutic drug from its characteristics such as its therapeutic results being the same as the conventional therapy by daily administration, excellent drug compliance, low cost, hard selectiveness of resistant strains, less side effects and furthermore it gives the opportunity of detecting a latent and mild underlying condition.

Acute Disease↗
PubMed1992

[A fifty two-week oral repeated dose toxicity study of suplatast tosilate (IPD-1151T) in dogs].

A 52-week oral repeated dose toxicity study of suplatast tosilate (IPD-1151T), a newly developed anti-allergic agent, was carried out in beagles by oral administration of 30, 90, 270 and 810 mg/kg/day for 52 weeks. The recovery study was carried out by the withdrawal for 5 weeks using control and the 810 mg/kg groups. The results are as follows: 1. Observation of general conditions revealed soft feces, mucous feces, and diarrhea in both sexes of the 270 and 810 mg/kg groups during the administration period, and these findings disappeared during the withdrawal period. One female of the 810 mg/kg group exhibited tremors in the legs and neck, staggering, a decrease of spontaneous motor activity, and clonic convulsions in Week 17 of administration and died on Day 118. One male of the same group exhibited whole body tremors and staggering from Week 32 to Week 52. 2. Body weight gain tended to be inhibited in males of the 810 mg/kg group during the administration period. The body weight of the female that died decreased rapidly after the appearance of neurological symptoms. The body weight of the male that exhibited neurological symptoms decreased after their appearance but later increased. 3. There were no abnormal changes in food consumption in all of the sacrificed dogs. The female that died did not eat at all after the appearance of neurological symptoms. The male that exhibited neurological symptoms did not eat at all for 1 week after their appearance, but the food consumption returned to normal thereafter. 4. Prothrombin times were prolonged in males of the 270 and 810 mg/kg groups at Week 26, and activated partial thromboplastin times were prolonged in males of the 810 mg/kg group at Week 52. 5. Plasma levels of alkaline phosphatase, GPT and LDH were elevated in some males and females of the 810 mg/kg groups. 6. No abnormalities due to IPD-1151T administration were found in urinalysis, opthalmological examination, electrocardiography, and fecal occult blood examination, or organ weights. 7. Autopsies including histopathological and electron microscopic examinations on the sacrificed dogs revealed no abnormalities. Subserosal hemorrhage in the base of the heart, congestion in the lungs, congestion and vacuolation in the liver and slight cell infiltration around vessels of the brain were found in the female that died.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗
PubMed1992

Ovarian and hepatic metastases of gastric carcinoma associated with high serum levels of human chorionic gonadotropin (hCG), alpha-fetoprotein (AFP), and carcinoembryonic antigen (CEA): a case report.

A 45-year-old woman who underwent gastrectomy for gastric carcinoma which had metastasized to the liver and ovaries, showed high serum levels of hCG, AFP and CEA. To locate the source, an immunohistochemical technique was utilized. HCG-producing cells were detected in poorly differentiated adenocarcinoma of a primary tumor and an ovarian metastatic site, and AFP-producing cells in poorly differentiated adenocarcinoma forming a medullary pattern of primary site and metastatic foci. CEA-producing cells were found diffused in primary tumor and metastatic foci. From the viewpoint of oncodevelopmental gene expression (Cancer Res 36:3423, 1976), it is interesting that the serum levels of these three tumor markers (hCG, AFP, CEA) were elevated simultaneously.

Biomarkers, Tumor↗