Biomedical subjects

K Aikawa

Publications and source records attributed to K Aikawa.

At least 73 records · Page 4Linked to original sources

PubMed1990

Enflurane reduces the excitation and inhibition of dorsal horn WDR neuronal activity induced by BK injection in spinal cats.

The effects of enflurane (0.5%, 1.5% and 2.5%) on the excitation and inhibition of dorsal horn wide dynamic range (WDR) neuronal activity induced by bradykinin (BK) injection was studied in spinal cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind paw foot pads of decerebrate, spinal cord transected (L(1-2)) cats. When 10 microg of BK was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus, 24 of 26 WDR neurons (92%) gave excitatory responses and 2 (8%) gave inhibitory responses. On the other hand, when the injection of 10 microg of BK into the femoral artery contralateral to the recording site was used as the noxious test stimulus, 7 of 12 WDR neurons (58%) gave inhibitory responses, 3 (25%) gave excitatory responses, and 2 (17%) showed no response. The excitatory neuronal activity in WDR neurons was not depressed by 0.5% or 1.5% enflurane but was depressed significantly by 2.5%. However, the inhibitory neuronal activity in WDR neurons was significantly depressed by 0.5%, 1.5% and 2.5% enflurane. We have found that enflurane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by BK injection. These results suggest that the reduction of excitatory and inhibitory responses produced by noxious stimulation is likely to be the fundamental basis of the enflurane-induced anesthetic state in terms of WDR neurons.

Journal Article↗

PubMed1989

Cellular injury and lipid peroxidation induced by hexavalent chromium in isolated rat hepatocytes.

In order to elucidate the relationship between cellular injury and lipid peroxidation induced by hexavalent chromium (CrVI), isolated rat hepatocytes treated with any one of scavengers of active oxygen species, antioxidants or antichromium agent were incubated with K2Cr2O7 as CrVI (1 mM Cr). After the incubation, the development of lipid peroxidation was determined as thiobarbituric acid (TBA)-reacting materials in total lipid extracts from the incubated hepatocytes. Cellular injury was observed as a leakage of lactate dehydrogenase (LDH) from hepatocytes into incubation medium. The contents of reduced glutathione (GSH) in hepatocytes were also assessed. Results obtained were as follows: (1) CrVI facilitated lipid peroxidation in isolated hepatocytes after 20 min of incubation. On the other hand, the cellular injury induced by CrVI was barely observed even after 60 min of incubation. (2) The CrVI-induced lipid peroxidation was inhibited by catalase and mannitol as scavengers of active oxygen species, or N,N'-diphenyl-p-phenylenediamine and alpha-tocopherol as antioxidants. However the cytotoxicity of CrVI could not be prevented by these chemicals. (3) CrVI depleted the contents of intracellular GSH and diminished the activities of glutathione reductase (GR) and glutathione-S-transferase (GST) except glutathione peroxidase. (4) The scavengers of active oxygen species and the antioxidants could not prevent the depletion of intracellular GSH induced by CrVI. (6) Ascorbic acid, antichromium agent, prevented all of the lipid peroxidation, the cellular injury and intracellular GSH depletion induced by CrVI.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

[Clinical evaluation of serum immunosuppressive acidic protein (IAP) and acid soluble glycoproteins (ASP) in patients with malignant tumors].

In order to study the clinical significance of IAP and ASP, we have measured serum concentration of IAP and ASP in patients with different cancer types including digestive organs, head and neck. Significantly higher correlation (coefficient of correlation = 0.924) was found between IAP and ASP. IAP and ASP levels were elevated in about 60-80% of cancer from digestive organs except hepatocellular carcinoma, and in about 56-100% of head and neck tumor. There was no correlation between IAP, ASP and various tumor markers (CEA, CA19-9, AFP) in all malignancies except pancreatic cancer. There was positive correlation between CEA and IAP, ASP in pancreatic cancer. IAP and ASP levels were significantly higher in patients with cancer having evidence of disease than the patients with cancer who had no evidence of disease, and so the determination of IAP and ASP was clinically useful for the diagnosis of tumor existence. At the time of diagnosis of recurrence, the levels of IAP and ASP were elevated in about 70% of patients with cancer recurrence. There was a definite relation between IAP, ASP and the gastric cancer stage. In later state (stage III and IV), serum IAP and ASP levels were significantly higher than the levels of stage I and II. In hepatocellular carcinoma without liver cirrhosis, the levels of IAP and ASP were higher than the patients with cirrhosis. The determination of IAP and ASP seems to be useful for monitoring clinical course, judgement of therapeutic effects.

Carcinoembryonic Antigen↗

PubMed1989

[Clinical significance of serum acid soluble glycoproteins (ASP) and immunosuppressive acidic protein (IAP) in inflammatory diseases and liver diseases].

In order to study the clinical significance of ASP and IAP, we have measured serum concentration of ASP and IAP in 259 patients with inflammatory diseases, non-inflammatory diseases, autoimmune diseases and liver diseases. Significantly higher correlation (coefficient of correlation = 0.922) was found between ASP and IAP. There were good correlation between ASP, IAP levels and erythrocyte sedimentation rate (ESR), C-reactive protein (CRP). Coefficient of correlation were 0.705 and 0.673 between ESR and ASP, IAP; 0.621 and 0.623 between CRP and ASP,IAP, respectively. There were food correlations between ASP levels and thrombo test (TT) and hepaplastin test (HPT). The positive rate and mean concentration of ASP, IAP in patients with inflammatory diseases were significantly higher than noninflammatory diseases. It is suggested that serum ASP, IAP could be one of the useful indicator for evaluating the clinical course of patients with inflammatory diseases. Serum concentration of ASP, IAP in patients with chronic liver diseases were lower than normal subjects, especially serum levels in patients with decompensated liver cirrhosis and chronic hepatitis (active) were significantly lower than normal subjects. In patients with hepatoma with cirrhosis, serum levels of ASP, IAP were significantly lower than the hepatoma patients without cirrhosis. The determination of ASP, IAP in liver diseases seems to be useful for evaluating the severity of diseases, the effects of therapy and the forecast of prognosis.

Autoimmune Diseases↗

PubMed1989

[Protective effects of ulinastatin on hepatic oxygen metabolism during halothane anesthesia in the presence of graded hypoxic hypoxemia].

Hepatic oxygen metabolism and the hepatic energy charge were assessed in mongrel dogs receiving 40,000 U.kg-1 of ulinastatin intra-portally during 2 MAC halothane anesthesia combined with graded hypoxic hypoxemia (21-6% oxygen) for the purpose of evaluating the role of ulinastatin in protecting the liver against the deprivation of the hepatic energy charge resulting in halothane-induced hepatotoxicity. Hepatic blood flow was measured using electromagnetic flowmetry; hepatic oxygen delivery and consumption were calculated from measured hepatic blood flow and oxygen content in hepatic arterial, portal venous and hepatic venous blood. In the animals who received ulinastatin during halothane anesthesia (the UST group), nine out of ten survived even at 8% oxygen, whereas six out of eight died in the halothane-alone group. There was no significant difference in total hepatic blood flow between the two groups. PaO2 was higher in the UST group than the halothane-alone group at 15 and 12% oxygen. Therefore hepatic oxygen delivery was significantly higher in the UST group at 15 and 12% oxygen. Hepatic oxygen consumption and the delivery/consumption ratio were also higher in the UST group at the various inspired oxygen levels. The arterial ketone body ratio, which indicates the mitochondrial energy charge level, significantly decreased with the progress of hypoxia in both groups, but it was significantly higher in the UST group at 8% oxygen.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Inhalation↗

PubMed1989

[Clinico-statistical study of inpatients and autopsied cases in our clinic].

The statistics of clinical observation at Department of Internal Medicine, Nippon Dental University at Niigata from July 1981 to December 1987 (duration 6.5 years) were as follows: Total number of inpatients: 1,238, Total number of death cases: 106. Findings include: 1) Ratio of male patients to female patients 1.34:1.00. Male deceased patients to female deceased patients 1.52:1.00. 2) Average patients number hospitalized per year was 200. The high percentaged of certain advanced aged groups was reflected by the recent demographic changes in the society in general.; in their 60's 46.0%, in their 70's 24.3%, in their 80's 6.7%. In these age groups, female number is tendency to increase the number of male. 3) The diseases of inpatients were mostly due to the digestive tract, which accounted for 60.4% of the total. Of this percentage, 65% was due to hepato-biliary diseases. 4) The death statistics of malignant tumor was 68.9%; Benign diseases being 31.1%. Male patients died from hepatocellar carcinoma, lung cancer, colon cancer and stomach cancer, in descending order. Females died from cancer of the biliary tract, stomach cancer and hepatocellular carcinoma, again, in descending order. 5) 71.7% of all deaths were caused by the digestive tract, in particular, hepatocellular carcinoma, cancer of the biliary tract, liver cirrhosis and primary biliary cirrhosis, all belonging primarily to the hepato-biliary disease group. 6) As a result of 58 autopsies performed for 106 death cases, 32 cases had complete autopsies and 26 cases had partial organ punctures.

Aged↗

PubMed1988

Antimutagenic effect of volatile decomposition products from thermally oxidized linoleate.

The antimutagenic effect of volatile decomposition products from thermally oxidized linoleate on mutagenesis by UV irradiation was investigated in Escherichia coli B/r WP2. When added to an agar medium, these products greatly reduced the number of Trp+ revertants. The same antimutagenic effect was observed by acrolein, 2-hexenal, 2-heptenal, 2-nonenal and 2,4-decadienal; these unsaturated aldehydes were components of volatile products.

Acrolein↗

PubMed1988