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Biomedical subjects

T Katoh

Publications and source records attributed to T Katoh.

At least 325 records · Page 18Linked to original sources

Effect of fentanyl on awakening concentration of sevoflurane.

This study was designed to determine if fentanyl altered MAC-awake (the end-tidal concentration of sevoflurane associated with eye opening to verbal command) in 30 healthy, ASA I patients. During anaesthesia, no other anaesthetics or drugs were given with the exception of sevoflurane. After surgery, end-tidal anaesthetic concentration was maintained constant for at least 15 min. If patients failed to respond to command, the end-tidal concentration was decreased and again maintained constant for 15 min. The anaesthetic concentration midway between the value permitting the response and that just preventing the response was recorded as MAC-awake. Fentanyl was administered at predicted plasma concentrations of 1 and 2 ng mg-1 using a computer-controlled continuous infusion and plasma concentrations of fentanyl were measured at the time of MAC-awake measurements. MAC-awake of the control group in which fentanyl was not administered was mean 0.67 (SD 0.12)% or 0.36 (0.03) MAC, being significantly higher than that of the fentanyl 2-ng ml-1 group (0.57 (0.09)% or 0.30 (0.04) MAC). In the fentanyl 1-ng ml-1 group, MAC-awake (0.65 (0.10)% or 0.34 (0.05) MAC) did not differ from that in the control group. Logistic regression analysis showed that increasing plasma concentration of fentanyl and increasing age significantly reduced the MAC-awake of sevoflurane. Because the reduction was very small relative to the overall scatter of the MAC-awake, a low plasma concentration of fentanyl did not significantly reduce the MAC-awake of sevoflurane.

Adult↗

A multicenter, randomized, controlled trial of intravenous gamma globulin therapy in children with acute Kawasaki disease.

We studied the effect of intravenous, polyethyleneglycol-treated, human immunoglobulin, administered at 200 mg/kg per day (group A: n = 147; male 86, female 61; age < 1 year, 50) or 400 mg/kg per day (group B: n = 152; male 87, female 65; age < 1 year, 52) for five consecutive days and compared it with freeze-dried, sulfonated human immunoglobulin [group C: n = 152; male 87, female 65; age < 1 year, 51), administered at 200 mg/kg per day for five consecutive days, on the prevention of coronary artery abnormalities in Kawasaki disease. Echocardiograms were interpreted blindly and independently. Proportions of 87.1%, 95.4%, and 82.3% in groups A, B, and C, respectively, had no coronary artery abnormalities. The confidence limits of difference between the proportions of groups A and C, groups B and C, and groups B and A were -4.4% and 10.4%, 7.8% and 15.9%, and 4.0% and 10.8%, respectively. Duration of fever and serum immunoglobulin G (IgG) levels were correlated with the prevalence of coronary artery abnormalities. We concluded that intravenous, polyethyleneglycol-treated, human immunoglobulin and freeze-dried, sulfonated human immunoglobulin had clinically equivalent effects on coronary artery abnormalities, and that five daily doses of 400 mg/kg of intravenous, polyethyleneglycol-treated, human immunoglobulin is more effective than that of 200 mg/kg gamma globulin.

Acute Disease↗

Synthesis and angiotensin converting enzyme-inhibitory activity of N-[(1S)-1-carboxy-5-(4-piperidyl)pentyl]-L-alanine derivatives.

As part of a search for potent and long-lasting angiotensin converting enzyme (ACE) inhibitors, various types of N-[(1S)-1-carboxy-5-(4-piperidyl)pentyl]-L-alanine derivatives (7a, 8-11) were prepared. The key synthetic intermediate, N-[(1S)-5-(1-benzyloxycarbonyl-4-piperidyl)-1- ethoxycarbonylpentyl]-L-alanine (17a), was synthesized by asymmetric reduction of the alpha-oxoester (13) with Lactobacillus paracasei subsp. paracasei followed by a substitution reaction with tert-butyl L-alaninate (15) and subsequent treatment with hydrogen chloride. Compounds 7a and 8-11 showed potent and long-lasting ACE-inhibitory activity in rats.

Alanine↗

[The frequency of glutathione-S-transferase M1 (GSTM1) gene deletion in patients with lung and oral cancer].

A homozygous gene deletion at the glutathione-S-transferase (GST) M1 locus of genomic DNA isolated from the peripheral blood was investigated for its relationship with lung and oral cancer using the polymerase chain reaction (RCR) technique. DNA samples were prepared from 91 healthy controls, 53 lung cancer patients and 48 oral cancer patients. As for the genotype, 38 of 91 healthy controls (41.7%), 27 of 53 lung cancer patients (50.9% [p > 0.05], odds ratio 1.45, 95% confidence interval 0.73-2.86) and 26 of 48 oral cancer patients (54.2% [p > 0.05], odds ratio 1.65, 95% confidence interval 0.82-3.32) were GSTM1 deletion types. When male-smoker patients and healthy controls were analyzed, the frequency of GSTM1 deletion genotype was 41.6% in the healthy controls and 52.2% (p > 0.05, odds ratio 1.53, 95% confidence interval 0.58-4.14), 54.5% (p > 0.05, odds ratio 1.68, 95% confidence interval 0.45-6.26), and 50.0% (p > 0.05, odds ratio 1.40, 95% confidence interval 0.55-3.60) in pulmonary squamous cell carcinoma, small cell carcinoma, intraoral squamous cell carcinoma patients, respectively. Thus, the GSTM1 deletion genotype as a host factor predisposing to lung and oral cancer could not be confirmed in this study.

Adenocarcinoma↗

Dietary supplementation with L-arginine ameliorates glomerular hypertension in rats with subtotal nephrectomy.

This study was designed to examine the potential effect(s) of dietary supplementation with L-arginine on the renal microcirculation of female Munich-Wistar rats with ablation of 60 to 70% of total renal mass. All rats were fed a standard rat chow containing 22.8% protein (1.42% L-arginine). Groups 1 (N = 6) and 3 (N = 7) drank tap water and had micropuncture studies after 5 to 6 or 15 to 16 wk, respectively, of subtotal renal ablation. Groups 2 (N = 5) and 4 (N = 7) drank tap water supplemented with L-arginine (1%) and had micropuncture studies after 5 to 6 or 15 to 16 wk, respectively, of subtotal renal ablation. Glomerular micropuncture studies revealed no differences in any of the parameters of glomerular hemodynamics measured 5 to 6 wk after renal ablation (Groups 1 versus 2). However, by 15 to 16 wk postnephrectomy, values of glomerular capillary pressure and efferent arteriolar resistance were significantly greater and the glomerular capillary ultrafiltration coefficient was significantly lower in rats drinking tap water than in rats drinking tap water supplemented with L-arginine. Single-nephron GFR, single-nephron plasma flow rate, and afferent arteriolar resistance were not different between these two groups. The data suggest that the long-term administration of L-arginine prevents the progression of glomerular sclerosis in rats with subtotal nephrectomy, at least in part, by ameliorating glomerular capillary hypertension.

Animals↗

Enhancement of antibody production in mice by dietary Spirulina platensis.

Mice fed a Spirulina platensis diet showed increased numbers of splenic antibody-producing cells in the primary immune response to sheep red blood cells (SRBC). However, immunoglobulin G (IgG)-antibody production in the secondary immune response was hardly affected. The percentage of phagocytic cells in peritoneal macrophages from the mice fed S. platensis diet, as well as the proliferation of spleen cells by either concanavalin A (Con A) or phytohemagglutinin (PHA) was significantly increased. Addition of a hot-water extract of S. platensis (SHW) to an in vitro culture of spleen cells markedly increased proliferation of these cells, whereas culture of thymus cells was scarcely affected. The Spirulina extract also significantly enhanced interleukin-1 (IL-1) production from peritoneal macrophages. Addition to the in vitro spleen cell culture of SHW as well as the supernatant of macrophages stimulated with SHW resulted in enhancement of antibody production, that is, an increase of the number of PFC. These results suggest that Spirulina enhances the immune response, particularly the primary response, by stimulating macrophage functions, phagocytosis, and IL-1 production.

Animals↗

[Significance of AKBR as an indicator of liver injury after cardiopulmonary bypass].

AKBR is a metabolic indicator related to NAD-linked dehydrogenase system, according to the REDOX theory. In order to estimate whether AKBR is a sensitive indicator of liver injury or not, we measured AKBR before and immediately after cardiopulmonary bypass (CPB) in 20 patients undergoing cardiac surgery and thoracic aortic aneurysmectomy. Twenty patients were divided into two groups: one with AKBR more than 0.7 (normal group) and the other with AKBR less than 0.7 (abnormal group). The AKBR in the abnormal group was significantly decreased after CPB (p < 0.05), though the AKBR in the normal group was unchanged. In addition, the normal group significantly showed high AKBR compared to the abnormal group after CPB (p < 0.01). Among 5 patients with GPT more than 50 IU/l, the number of patients with AKBR more than 0.7 was zero and with AKBR less than 0.7 was 5 patients. The normal group has a lower risk of liver injury than the abnormal group. The normal group had a higher hepatic perfusion pressure compared with abnormal group. However, there were not significant differences in the cardiac functions (cardiac output, LVSWI and RVSWI) after the CPB between two group, whereas the CPB time and the aortic clamping time in the abnormal groups were longer than those in the normal group. We concluded that the AKBR is a sensitive indicator of liver function after the CPB.

Cardiac Surgical Procedures↗

[The concentration effects of isoflurane-N2O anesthesia on cardiovascular responses to skin incision].

To investigate the concentration effects of isoflurane-nitrous oxide anesthesia on cardiovascular responses to skin incision, we studied 24 non-premedicated patients undergoing lower abdominal operation. Anesthesia was induced with inhalation of 70% nitrous oxide and isoflurane, and maintained with 70% nitrous oxide and three different concentrations of isoflurane (1.25, 1.6, 1.95 MAC). Blood pressure and heart rate were recorded continuously before and after skin incision. Because more than half the patients with 1.95 MAC became hypotensive with systolic blood pressure of less than 80 mmHg just before the skin incision, it was difficult to define the values of MAC BAR (blocking adrenergic responses) in the present study. Cardiovascular responses at skin incision were not completely suppressed at 1.6 MAC isoflurane-N2O anesthesia and no further blocking effects were obtained at 1.95 MAC isoflurane-N2O anesthesia. These results suggest that higher concentration of isoflurane does not guarantee stronger protective effects on stimulation like skin incision.

Abdomen↗

[Aspiration cytology of salivary gland lesions--analysis of 55 cases].

Aspiration cytology of 55 salivary gland lesions (10 cases of non-neoplastic lesions, 36 cases of benign tumors and 9 cases of malignant tumors) were reviewed with histologic examination. Accuracy of benign and malignancy was 91.8% (benign lesion 97.6%, malignant tumor 57.1%), accuracy rates was almost of satisfactory for benign lesions, but not for malignant tumors. Agreement rate with histological type was 73.5%. One case (1.8%) was false positive, basal cell adenoma with adenoid cystic like pattern was falsely taken for adenoid cystic carcinoma. Three false negative cases (5.5%) consist of 1 acinic cell carcinoma, 1 adenoid cystic carcinoma with minimum cellular atypia and 1 partial malignant change (minor area) in pleomorphic adenoma. Six cases (10.9%) belong to group of insufficient material. Technical improvement of cell sampling is expected.

Biopsy, Needle↗

The effects of X-ray energy and an iodine-based contrast agent on chromosome aberrations.

A study was undertaken to evaluate the effect of combining irradiation with X rays of various energies and an iodine-based contrast agent on the induction of chromosome aberrations in the peripheral lymphocytes of blood samples taken from healthy young donors. Although no enhancement of the effect of radiation was induced when blood samples with the iodine-based contrast agent were given 35 kV X irradiation, an 80 kV X-ray exposure induced an enhanced level of chromosome aberrations, and at 250 kV X irradiation, an enhancement of the frequencies of chromosome aberrations was seen in blood samples with the iodine-based contrast agent, especially when a Lucite phantom was employed in studies to increase the scattered rays. It was thus shown by microdosimetric analysis that X irradiation combined with an iodine-based contrast agent causes an enhancement of the absorbed radiation dose, which is dependent on the X-ray energies employed. This phenomenon may have clinical use in the radiotherapeutic management of tumors, although further extensive studies of tumor vascularity must be pursued before this can be applied clinically.

Adult↗

[Diagnosis of the pancreatic diseases by intraductal ultrasound of the pancreas--with special reference to clinical cases difficult to diagnose differentially pancreatic diseases by the endoscopic retrograde pancreatography].

We examined the usefulness of the intraductal ultrasound (IDUS) examinations by comparing the IDUS images with the endoscopic retrograde (ER) pancreatograms. We inserted an IDUS probe with 30 MHz at frequency transpapillary into the main pancreatic duct (MPD) in 105 cases with pancreatic diseases (30 cancers, 30 mucin-producing tumor, 3 islet cell tumor, 1 pancreatic serous cyst adenoma, 1 pancreatic teratoma, 1 pancreatic solid and cystic tumor and 39 chronic pancreatitis). All 105 cases were performed ER pancreatography. Sixty-four of 105 cases (22 cancers, 20 mucin-producing tumor, 3 islet cell tumor, 1 pancreatic serous cyst adenoma, 1 pancreatic teratoma, 1 pancreatic solid and cystic tumor and 16 chronic pancreatitis) were operated and the IDUS images were compared with the corresponding histopathological sections. The usefulness of the IDUS examinations of the pancreatic diseases were the following cases; differential diagnosis between benign and malignant cases with localized stenosis of the MPD, differential diagnosis of the cases with displacement of the MPD, and the diagnosis of the intraductal extent and of invasion of the tumor in the mucin-producing tumor of the pancreas with the dilation of the MPD. IDUS examinations are performed by the IDUS probe with high frequency, so the indications of the IDUS examinations are to detect the small lesions in the pancreas.

Cholangiopancreatography, Endoscopic Retrograde↗

Excitatory amino acid receptor binding in hippocampus of gerbils with transient global brain ischemia.

Binding of a variety of ligands for brain excitatory amino acid receptors was examined in membrane preparations extensively washed and treated with Triton X-100 that were obtained from the hippocampus and cerebral cortex of gerbils that survived for different periods after transient global brain ischemia. Bilateral occlusion of the carotid arteries for 5 min did not affect the binding of [3H](+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imi ne (MK-801) to an open ion channel associated with the N-methyl-D-aspartate (NMDA)-sensitive subclass in both central structures of gerbils that survived for 1 to 4 weeks after the injury when determined at equilibrium in the presence of 3 different endogenous agonists including L-glutamic acid (Glu), glycine (Gly) and spermidine at maximally effective concentrations. In contrast, the ischemic occlusion significantly diminished [3H]MK-801 binding when determined before equilibrium in the presence of the 3 stimulants in hippocampal membranes without altering that in cortical membrane 2 weeks after the insult, so that the initial association rates were invariably reduced by more than 60%. Moreover, the occlusion not only reduced the binding of both [3H]Glu and [3H]D,L-(E)-2-amino-4-propyl-5-phosphono-3-pentenoic acid to the NMDA domain on the NMDA receptor ionophore complex, but also decreased the binding of both [3H]Gly and [3H]5,7-dichlorokynurenic acid to the Gly domain. However, the insult did not induce any detectable changes under the experimental conditions employed in either the binding of [3H]DL-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) to the AMPA-sensitive subclass or the binding of kainic acid (KA) to the KA-sensitive subclass in both central regions of animals that survived for 2 weeks. These results suggest that transient global brain ischemia may predominantly impair neuronal and/or glial cells enriched of the NMDA receptor ionophore complex in gerbil hippocampus.

Animals↗