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Biomedical subjects

T Sakai

Publications and source records attributed to T Sakai.

At least 487 records · Page 27Linked to original sources
PubMed1998

In vivo spasmolytic effect of ketamine and adrenaline on histamine-induced airway constriction. Direct visualization method with a superfine fibreoptic bronchoscope.

BACKGROUND: Ketamine (K) has been reported to produce bronchodilation in patients suffering from asthma. Although most researchers have used indirect measurements to study the effect of K in vivo, the reliability of these indirect methods are controversial. We have developed a new technique to measure the bronchial cross-sectional area (BCA) in vivo with a superfine fibreoptic bronchoscope (SFB). Employing this method, we evaluated in vivo spasmolytic effect of K and adrenaline (A). METHODS: Twenty-one mongrel dogs were anaesthetized with pentobarbitone (30 mg.kg-1) and paralyzed with pancuronium (200 micrograms.kg-1.h-1). The trachea was intubated with an endotracheal tube that has a second lumen for insertion of a SFB (OD: 2.2 mm) to measure the BCA continuously. The tip of the SFB was placed between the 2nd and 3rd bronchial bifurcation of the right lung. A videoprinter printed the BCA, which was then measured with NIH Image. Bronchoconstriction was produced with histamine (H: 10 micrograms.kg-1 + 500 micrograms.kg-1.h-1) which was administered until the end of the experiment. The BCA was assessed before and 30 min after the start of H infusion. The dogs were randomly allocated to 3 groups of 7 dogs each. In group K, K (0-10 mg.kg-1) was given i.v., and the BCA was measured 5 min after each K dose. In group A, A (0-0.4 microgram.kg-1) was given i.v., and the BCA was measured 1 min after each A dose. In group A + K, K (1 mg.kg-1 i.v. + 1 mg.kg-1.h-1 i.v.) was given followed, 30 min after, by A i.v. in the same doses as in group A. The BCA was assessed 30 min after the start of K and again 1 min after each A dose. RESULTS: K 10 mg.kg-1 reversed H-induced bronchoconstriction. A subthreshold dose of K significantly potentiated the effect of A, reversing the decrease in BCA by H. CONCLUSION: We have found that K could reverse the H-induced bronchoconstriction and potentiate the A-induced bronchial relaxation.

Animals↗
PubMed1998

Case report: a long-term survivor of jejunal leiomyosarcoma with liver metastasis: effective transcathetel arterial embolization for hepatic metastatic foci.

We report a case of jejunal leiomyosarcoma with liver metastases in a 52-year-old Japanese male. An echogram demonstrated multiple cystic liver masses in April 1991. The diagnosis of metastatic leiomyosarcoma was made on the basis of characteristic hepatic angiography images and liver biopsy findings. The jejunal leiomyosarcoma was resected and unresectable liver metastatic foci were treated repeatedly with transcathetel arterial embolization. Transcathetel arterial embolization was considered to be effective in this case as the patient survived 4 years and 9 months after the first treatment.

Catheterization↗
PubMed1998

Prolonged polysomnography in a case with recurrent hypersomnia.

An 18-year-old male patient with recurrent hypersomnia (RH) was evaluated using prolonged polysomnography (PSG). During symptomatic period (SMP), the patient showed both 'dissociated stage REM' (DREM), REM sleep without muscle atonia and 'dissociated stage 1' (DSt-1), and stage 1 sleep with rapid eye movement. These stages were observed in the morning or following daytime record. They decreased during asymptomatic period (ASMP). It has been said that RH is caused by dysfunction of the hypothalamus and midbrain limbic system. The present result suggests also that RH involves dysfunction of the brain stem.

Adolescent↗
PubMed1998

Postoperative inflammatory reaction developing focal but severe brain edema. A possible complication of topical application of Biobond-soaked oxycellulose.

A 66-year-old female underwent uneventful removal of parasagittal meningioma. At surgery, a piece of Biobond-soaked oxycellulose was applied to the lateral wall of the superior sagittal sinus for hemostasis. Her early postoperative course was complicated by focal but severe brain edema, which was adjacent to the hemostatic agent. Unlike foreign body granuloma previously reported, this complication was considered to be attributed to inflammatory reaction of Biobond, because of the early onset and fulminant edema despite of small volume of the mass lesion. Although there have been no previous reports of this complication, it should be kept in mind that intracranial application of Biobond may induce fulminant inflammatory reaction as seen in this patient.

Acute-Phase Reaction↗
PubMed1998

Autologous blood donation preceding coronary artery bypass graft operation in a hemodialysis patient.

A 67-year-old male hemodialysis patient with abdominal aortic aneurysm and triple vessel coronary heart disease required autologous blood donation because of his blood type of Rh(-) before cardiovascular surgery. We performed autologous red blood cell and plasma collection by the switch back method with recombinant human erythropoietin therapy during the 5 weeks before the operation. Autologous platelet collection was also made the day before the operation. These autologous blood donations were safely and successfully performed along with hemodialysis. There was some caution taken for these procedures. The ultrafiltration rate had to be adjusted for blood collection or blood transfusion during hemodialysis in order not to disturb fluid balance. It was necessary to monitor the hyperkalemia of the stored autologous packed red blood cells. For platelet collection, blood in the extracorporeal circuit had to be concentrated because of the presence of renal anemia. Coronary artery bypass graft was safely and successfully performed with the autologous blood only.

Aged↗
PubMed1998

Distribution of G serotypes and P genotypes of bovine group A rotavirus isolated in Japan.

OBJECTIVE: To identify the distribution of G serotype and P genotype of bovine group A rotavirus in Japan. DESIGN: Detection, isolation, electropherotyping, G serotyping and P genotyping of bovine group A rotavirus in 167 diarrhoeal faecal samples. PROCEDURE: Bovine group A rotavirus was detected and isolated, and bovine group A rotavirus isolates were identified electropherotype by polyacrylamide gel electrophoresis and G serotype and P genotype by reverse transcription-poly-merase chain reaction. RESULTS: Twenty-eight bovine group A rotavirus strains were isolated from 167 samples. Electropherotypes of the bovine group A rotavirus isolates were identified as long-genome electropherotype and the most prevalent combination of G serotype and P genotype of the bovine group A rotavirus isolates was G6P5 (25/28; 89.3%), followed by G6P11 (2/28; 7.1%) and G10P11 (1/28; 3.6%). CONCLUSION: These results suggest that the bovine group A rotavirus exhibiting G6P5 is the most common in Japan.

Animals↗
PubMed1998

[Incidence of antibodies in raccoon dogs and deer inhabiting suburban areas].

We evaluated the incidence of antibodies against canine distemper (CD) virus, canine parvovirus, Toxoplasma gondii (T. gondii), Aujeszky's disease virus, porcine reproductive and respiratory syndrome virus, Rickettsia tsutsugamushi, Rickettsia japonica, and Coxiella burnetii in 30 raccoon dogs and 5 deer captured in suburban areas in Kanagawa Prefecture. Among the raccoon dogs, anti-T. gondii antibody was detected in 1 animal (3.3%) and anti-CD virus antibody in 9 (30.0%). However, antibodies against the other pathogenic microorganisms were not detected in the raccoon dogs. The deer had none of the examined antibodies.

Animals↗
PubMed1998

Differential normalization of mucosal interleukin-8 and interleukin-6 activity after Helicobacter pylori eradication.

There is differential resolution of mucosal infiltration with neutrophils and mononuclear cells following successful Helicobacter pylori eradication. We investigated the effects of H. pylori eradication on mucosal interleukin-8 (IL-8) and IL-6 activity in relation to the resolution of H. pylori-associated gastritis. Eighty-one duodenal ulcer patients with H. pylori infection received dual- or triple-treatment eradication therapy, and mucosal biopsy specimens obtained at the initial and follow-up endoscopic examinations were cultured in vitro for 24 h. The levels of IL-8 and IL-6 were measured by enzyme-linked immunosorbent assays. In the 42 patients in whom H. pylori eradication failed, there was little change in the numbers of neutrophils and mononuclear cells infiltrating the mucosa and in IL-8 and IL-6 activity. In the 39 patients in whom H. pylori was eradicated, there was normalization both in the numbers of infiltrating neutrophils and in mucosal IL-8 activity, which was evident within 1 month following therapy. In contrast, there was a gradual resolution of mononuclear cell infiltration over a 6-month period, accompanied by a gradual normalization in IL-6 levels. Addition of H. pylori to cultures of mucosal tissues induced a significant increase in IL-8 activity in both uninfected control subjects and patients from whom H. pylori was eradicated. However, this introduction yielded a significant increase in IL-6 activity only in the latter group. This study indicates a dichotomy in the changes of mucosal IL-8 and IL-6 activity after H. pylori eradication. The rapid normalization of IL-8 after H. pylori eradication and the ability of H. pylori cells to stimulate IL-8 in control tissues indicate that IL-8 induction is a part of the innate (nonimmune) responses to this organism. In contrast, the results of experiments analyzing IL-6 activity in cultured mucosal tissues suggest that the gradual resolution of mucosal IL-6 activity and mononuclear infiltration after successful eradication observed in vivo may reflect gradually diminishing residual immune responses against H. pylori.

Adult↗
PubMed1998

Functional replacement of the intracellular region of the Notch1 receptor by Epstein-Barr virus nuclear antigen 2.

The intracellular region (RAMIC) of the mouse Notch1 receptor interacts with RBP-J/CBF-1, which binds to the DNA sequence CGTGGGAA and suppresses differentiation by transcriptional activation of genes regulated by RBP-J. Epstein-Barr virus nuclear antigen 2 (EBNA2) is essential for immortalization of human B cells by the virus. EBNA2 is a pleiotropic activator of viral and cellular genes and is targeted to DNA at least in part by interacting with RBP-J. We found that EBNA2 and the Notch1 RAMIC compete for binding to RBP-J, indicating that their interaction sites on RBP-J overlap at least partially. EBNA2 and Notch1 RAMIC transactivated the same set of viral and host promoters, i.e., the EBNA2 response element of the Epstein-Barr virus TP1 and the HES-1 promoter. Furthermore, EBNA2 functionally replaced the Notch1 RAMIC by suppressing differentiation of C2C12 myoblast progenitor cells.

Animals↗
PubMed1998

Differential expression of laminin receptors in human hepatocellular carcinoma.

BACKGROUND: Laminin receptors are involved in cell-extracellular matrix interactions in malignant cells that show invasion and metastasis. Hepatocellular carcinoma frequently shows early invasion into blood vessels, and intrahepatic and extrahepatic metastases. However, the role of laminin receptors in hepatocellular carcinoma is unknown. AIMS: To examine the expression of mRNA for laminin receptors and their isoforms in hepatocellular carcinoma. METHODS: The expression of several laminin receptors, including alpha1 integrin, alpha6 integrin and its isoforms alpha6A and alpha6B, beta1 integrin and its isoforms beta1A and beta1B, and 32kD/67kDa laminin binding protein was examined in human hepatocellular carcinomas and non-cancerous liver tissues using the reverse transcription polymerase chain reaction. RESULTS: Alpha6 Integrin, beta1 integrin, and laminin binding protein showed notably increased expression in hepatocellular carcinoma, compared with non-cancerous liver tissue, although the alpha1 integrin did not show a significant change. Furthermore, beta1B integrin, a splicing variant of beta1 integrin, was overexpressed in hepatocellular carcinoma while the beta1A integrin isoform did not show significant changes between hepatocellular carcinoma and surrounding non-cancerous liver tissue. CONCLUSIONS: The differential upregulation of laminin receptors and their splicing isoforms was shown in hepatocellular carcinoma, suggesting that certain laminin receptors and their isoforms may be involved in the development and progression of hepatocellular carcinoma.

Aged↗
PubMed1998

Effect of meal induced splanchnic arterial vasodilatation on renal arterial haemodynamics in normal subjects and patients with cirrhosis.

AIMS: To investigate the relation between changes in splanchnic arterial haemodynamics and renal arterial haemodynamics in controls and patients with cirrhosis. METHODS: Superior mesenteric artery pulsatility index (SMA-PI) and renal artery pulsatility index (R-PI) were measured using Doppler ultrasonography in 24 controls and 36 patients with cirrhosis. These measurements were repeated 30 minutes after ingestion of a liquid meal or placebo. Sixteen controls and 24 patients received the meal, and eight controls and 12 patients received placebo. RESULTS: In the fasting condition, patients with cirrhosis had a lower SMA-PI (p<0.01) and a greater R-PI (p<0.01) compared with controls. Placebo ingestion had no effect on splanchnic and renal haemodynamics. In contrast, ingestion of the meal caused a notable reduction in SMA-PI (p<0.01, p<0.01) and an increase in R-PI (p<0.01, p<0.01) in controls and patients with cirrhosis. The meal induced haemodynamic change in SMA-PI was inversely correlated with that in R-PI in controls (t=-0.42, p<0.05) and in patients with cirrhosis (t=-0.29, p<0.05). CONCLUSIONS: Results support the hypothesis that renal arterial vasoconstriction seen in patients with cirrhosis is one of the kidney's homoeostatic responses to underfilling of the splanchnic arterial circulation.

Blood Pressure↗
PubMed1998

Interferon therapy for chronic hepatitis C in hemodialysis patients: increased serum levels of interferon.

BACKGROUND/AIMS: The efficacy and side effects of interferon (IFN) therapy have not been well clarified in hemodialysis patients with chronic hepatitis C. METHODS: In 6 of 9 hemodialysis patients with chronic hepatitis C, 3 million units (MU) or 6 MU of recombinant IFN-alpha2b or natural IFN-alpha were administered intramuscularly daily for the first 2 weeks, followed by three times a week for 22 weeks. In the remaining 3 patients, 3 MU of IFN-alpha2b were given three times a week for 24 weeks. Serum concentrations of IFN-alpha2b were measured sequentially after the injection of interferon. Responders were defined as the patients with normal serum aminotransferase and negative serum HCV RNA 6 months after the cessation of IFN therapy. RESULTS: Three of the 6 patients who were administered IFN daily in the first 2 weeks were responders, while the other 3 withdrew from the therapy due to serious adverse events such as depression, loss of consciousness and persistence of high-grade fever. Serious adverse events were not observed in the 3 patients without daily administration. Half-lives of IFN-alpha2b in hemodialysis patients were significantly longer than those in nonuremic patients (10.0 vs. 6.0 h, p < 0.05). Moreover, the areas under the serum concentration curve of the hemodialysis patients were significantly larger than those of nonuremic patients (756 +/- 223 vs. 324 +/- 223 IU.h/ml, p < 0.05), despite the fact that the dose of IFN-alpha administered to hemodialysis patients was half that administered to nonuremic patients. CONCLUSIONS: In hemodialysis patients with chronic hepatitis C, pharmacokinetic parameters of IFN may be different from those in nonuremic patients, and daily or high-dose administration of IFN may lead to serious adverse events in those patients.

Adult↗
PubMed1998

Effects of dietary shrimp, squid and octopus on serum and liver lipid levels in mice.

The effects of three seafoods, shrimp, squid and octopus, on lipid metabolism were investigated in mice fed on 0.1% and 1.0% cholesterol-supplemented diets in the first experiment. One of each of these seafoods and casein were added to the basal diet at levels of 15% and 5%, respectively, as proteins. Casein served as the sole protein source of the control diet. The serum cholesterol concentration was significantly lower in the mice fed on shrimp and squid in the 0.1% cholesterol diet and on any seafood in the 1.0% cholesterol diet when compared with that in the mice fed on the control diet. The liver cholesterol concentration was significantly lower in all seafood groups given the 0.1% cholesterol diet, and in the squid and octopus groups given the 1.0% cholesterol diet. In the second experiment, the effect of these seafoods on lipid metabolism was compared with that of their defatted products in mice fed on a 0.2% cholesterol diet. Defatting resulted in an increase in the serum cholesterol and triglyceride levels in the shrimp and squid groups. The hepatic cholesterol concentration in all the seafood groups was significantly lower than that in the control group, and defatting did not influence the liver cholesterol concentration. Fecal total steroid excretion was higher in all the seafood groups when compared with that in the control group, and was not modified by the removal of fats. Thus, shrimp, squid and octopus exerted hypolipidemic activity; the serum cholesterol-lowering activity of shrimp and squid was attributed to their lipid fraction, whereas the non-lipid fraction of shrimp, squid and octopus contributed to a reduction of hepatic cholesterol and an increase of fecal steroid excretion.

Animal Nutritional Physiological Phenomena↗
PubMed1998

Relationships between 4-hydroxy-2-nonenal, 2-thiobarbituric acid reactive substances and n-6 polyunsaturated fatty acids in refrigerated and frozen pork.

The relationships between 4-hydroxy-2-nonenal (HNE), 2-thiobarbituric acid reactive substances (TBARS) and n-6 polyunsaturated fatty acids (n-6 PUFAs) were investigated for pork stored at 0, -20 and -80 degrees C. A significant linear correlation was apparent between HNE and TBARS for the pork stored at each temperature. However, the n-6 PUFA content remained unchanged during storage.

Aldehydes↗
PubMed1998

Seroprevalence against Toxoplasma gondii in domiciled cats in Japan.

A serological survey with latex agglutination test to detect anti-Toxoplasma gondii antibodies was conducted on 800 serum samples collected from domiciled cats at animal hospitals in various areas of Japan. The overall prevalence was 6.0% (48/800). Among 48 positive individuals, there was no specific distribution of strength of antibody titers; the titers were 1:64 in 8 cats, 1:128 in 12, 1:256 in 8, 1:512 in 10, 1:1,024 in 8 and 1:2,048 in 2. The maximum prevalence was 15.4% in 13 cats at 17-23 yrs old group, whereas all were negative in 58 cats aged 12-16 yrs. The age groups in the order of higher prevalence were 8, 4, 10, 5, 3, and 7 yrs, showing no aging effect to the prevalence. In terms of rearing conditions of those cats, they were classified into 4 groups, i.e., indoor, free, outdoor, and others. The prevalence in the outdoor group (11.1%) was significantly higher (p < 0.05) than that in the free group (4.8%). Epidemiological aspects observed in the domiciled cats were different from those reported in the stray cats.

Animals↗
PubMed1998

Molecular cloning of bottle-nosed dolphin (Tursiops truncatus) MHC class I cDNA.

Using polymerase chain reaction, bottle-nosed dolphin (Tursiops truncatus) major histocompatibility complex (DoLA) class I alpha chain cDNA was cloned and sequenced. Predicted amino acid sequences of DoLA class I alpha chain have cystein residues for intradomain disulfide bond formation and N-linked glycosylation sites, suggesting that DoLA class I alpha chain molecules construct alpha 1, alpha 2, and alpha 3 domain structures. Similarity of DoLA class I alpha chain cDNA to land mammal MHC class I alpha chain cDNA was 90.4% in cattle, 90.2% in horse, 89.4% in sheep, and 87.8% in human. This investigation suggests that DoLA is closely related to land mammals.

Amino Acid Sequence↗
PubMed1998

A monoclonal antibody against dolphin lymphocytes (6E9) which recognizes bovine MHC class II antigens.

A monoclonal antibody, 6E9 established from mice injected with dolphin peripheral blood lymphocytes (PBLs) was characterized. In addition to its reactivity against 89.4% of dolphin PBLs, 6E9 reacted with 33.1% of bovine PBLs of which 22% were CD5+, 11.1% were CD5-. 6E9 recognized a 34 kD protein on the surface of dolphin and bovine PBLs. Analysis of the protein's N-terminal amino acid sequence indicated that 6E9 recognizes bovine major histocompatibility complex (MHC) class II antigens. These results suggested that 6E9 recognized MHC class II antigens on bovine PBLs. As we have already produced an anti-dolphin MHC class I monoclonal antibody, analysis of immune system using these monoclonal antibodies will advance our understanding of the evolution of the mammalian immune system.

Animals↗