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Biomedical subjects

Y Kosaka

Publications and source records attributed to Y Kosaka.

At least 127 records · Page 7Linked to original sources

Rapid determination of hepatitis B surface antigen (HBsAg) by latex agglutination using an integrating sphere turbidimetric assay.

A method for determining levels of serum HBs antigen has been developed, applying the principles of the integrating sphere turbidimetric assay (ISTA). Using this method, the minimum detectable level of HBs antigen is 15 ng/ml, i.e., it is three times more sensitive than the reversed passive hemagglutination (RPHA) method. Reproducibility and specificity are also excellent with ISTA. With a cut-off level of 20 ng/ml, the highest reading possible with this method is 1000 ng/ml. Serum HBs antigen can readily be measured by this method if a fully automated EL-1000 analyzer is used. This rapid and simple method of measurement should be clinically useful.

Alanine Transaminase↗

Quick assay of serum HBs antibody levels using latex agglutination-integrating sphere turbidimetric assay (ISTA).

A method for determining serum HBs antibody applying the principle of integrating sphere turbidimetric assay (ISTA) by latex agglutination was developed. The minimum detectable level of HBs antibody by this method is 12.5 IU/L, indicating that this method is 3 times or more sensitive with better reproducibility and specificity than the passive hemagglutination (PHA) method. With a cut-off level of 25 IU/L, the possible highest simultaneous reading by this method was 1,000 IU/L. Serum HBs antibody can be readily measured in 10 or so minutes by this method if a fully automated EL-1000 analyzer is used. This rapid and simple method for determining serum HBs antibody will be useful not only clinically, but also in preventive medicine.

Enzyme-Linked Immunosorbent Assay↗

Differences in the assessment of postoperative pain when evaluated by patients and doctors.

This study was undertaken to compare the assessment of pain intensity by 59 patients and by their doctors according to a visual analogue scale (VAS) at rest and when coughing at 5 and 20 hr after major abdominal surgery. The rating given by the patients, who received epidural analgesia to relieve postoperative pain, was significantly above, and moreover, significantly correlated with that given by the doctors at any time or under any condition of the assessment. However, the correlation between the ratings given by patients and doctors at rest at 5 hr after surgery was low (r = 0.39, rs = 0.38) and significantly different from that when coughing at 20 hr after the operation (r = 0.79, rs = 0.80). Our findings indicate that the assessment of postoperative pain may be associated with some unreliability, especially during early periods, when using the subjective or objective-rated VAS at rest separately, and thus requires the combined use or the concomitant use of the VAS when coughing. Substitutional use of the objective-rated VAS for the subjective-rated VAS is not advised.

Journal Article↗

Effect of extradural anaesthesia on the ventilatory response to hypoxaemia.

The effect of lumbar or thoracic extradural anaesthesia on the ventilatory response to progressive isocapnic hypoxaemia was studied in two groups of 10 unpremedicated patients. The ventilatory measurements were taken twice, before and 20 min after the administration of 10 ml of lignocaine 2%. Lumbar extradural anaesthesia did not change the slope of the hypoxic response curve, but it significantly increased minute ventilation by 27% at an arterial oxygen saturation of 90%. Thoracic extradural anaesthesia was not associated with any changes in either index. We conclude that neither lumbar nor thoracic extradural anaesthesia impairs the ventilatory response to progressive isocapnic hypoxaemia.

Adult↗

Epidural anesthesia in a patient with myasthenia gravis.

We present a patient with myasthenia gravis who was safely managed by epidural anesthesia during and after thymectomy. An epidural catheter was inserted via the C7-T1 intervertebral space and 2% lidocaine was used during the surgery. The level of analgesia as determined by pinprick extending from C5 to T6. Epidural morphine or morphine and bupivacaine were used for postoperative pain relief. We evaluated ventilatory responses to CO2 and hypoxia after epidural anesthesia with lidocaine or morphine, and during continuous epidural infusion of the mixture of morphine and bupivacaine. Ventilatory responses to CO2 and hypoxia were both depressed following epidural injection of morphine. However, depression of ventilatory responses was not demonstrated following continuous epidural infusion of a mixture of morphine and bupivacaine. This case report suggests that epidural anesthesia is useful as a primary anesthetic and for postoperative pain control in patients with myasthenia gravis.

Adolescent↗

Hepatitis in an adult with rubella.

Rubella was accompanied by hepatic dysfunction in a 28-year-old male. Serum aminotransferase levels were moderately elevated and LDH markedly increased, especially LDH isoenzyme 5, whereas total bilirubin and ALP remained almost normal. GOT, GPT and LDH levels were completely normalized by the 21st hospital day. Paired antibody titers of viruses which may cause hepatitis, other than rubella, were of no significance. Laparoscopy showed enlarged, red liver. Histologic and electron microscopic findings of the liver were consistent with acute hepatitis. Hepatic damage with rubella is rare, and it is possible that the hepatic dysfunction seen in adult rubella may be mediated by an immunopathologic mechanism.

Acute Disease↗

The antimicrobial activity in vitro of cefpirome and 6 other beta-lactam antibacterial agents against clinical isolates.

The in vitro activity of cefpirome (CPR) was compared with that of cefazolin (CEZ), cefotiam (CTM), flomoxef (FMOX), cefotaxime (CTX), ceftazidime (CAZ) and imipenem/cilastatin (IPM/CS) against 384 clinical isolates, for tested by the both microdilution method. The activity of CPR against Staphylococcus aureus (MIC50, 1 microgram/ml) and Enterococcus faecalis (MIC50, 8 micrograms/ml) was better than CTX and CAZ, but slightly less than IPM/CS. CPR and other antibacterial agents were not effect against methicillin resistant S. aureus and Enterococcus faecium. The activity of CPR against Enterobacteriaceae was as good as that of CTX, CAZ, and IPM/CS, and more effective than CEZ, CTM and FMOX. The MIC50 of CPR for Acinetobacter calcoaceticus (2 micrograms/ml) and the MIC50 of CPR for Pseudomonas aeruginosa (8 micrograms/ml) were as good as that of CAZ. Conclusionly, CPR was a new broad spectrum cephalosporin as compared with used cephalosporins.

Anti-Bacterial Agents↗

[Adequate hepatic circulation during induced hypotension].

The effects of prostaglandin E1 (PGE1) on the hepatic circulation was investigated in an extreme situation during acute hemorrhagic hypotension. Eighteen mongrel dogs were divided into two groups of those who received intravenous injection of PGE1 (PGE1 group, n = 9) and those who received control solution (non-PGE1 group n = 9). After anesthetizing dogs with 50% nitrous oxide in oxygen and 0.5% halothane, surgical procedure was carried out. Mean arterial pressure decreased to 50 mmHg by acute exsanguination, and this pressure was maintained by either saline (2.4 ml.kg-1 x h-1) or PGE1 (0.2 microgram.kg-1 x min-1) infused continuously for 2 hours. In dogs, PGE1 maintained the total hepatic blood flow with increased cardiac index and decreased splanchnic vascular resistance, in spite of the decreased mean arterial blood pressure during hemorrhagic hypotension. The result suggests that, in a hypotensive condition PGE1 may be useful in maintaining adequate hepatic circulation.

Acute Disease↗

[Blood gas changes during laparoscopic cholecystectomy--comparative study of N2O pneumoperitoneum and CO2 pneumoperitoneum].

During laparoscopic cholecystectomy by alternative insufflation of nitrous oxide and carbon dioxide, the changes of blood gas tensions were measured and analyzed in 12 patients. During N2O insufflation, PaO2 decreased by about 25 mmHg and PaCO2 was unaltered compared with the values before pneumoperitoneum. While during CO2 insufflation, PaO2 decreased by about 13 mmHg and PaCO2 increased by about 6 mmHg. We considered that decrease in PaO2 during N2O insufflation was associated with not only uneven ventilation/blood flow ratios but also with the reduction in the alveolar O2 tension caused by the diffusion of N2O absorbed from the peritoneum. PaCO2 increases during CO2 insufflation because CO2 is absorbed from the peritoneum, and is not excreted entirely through the lungs.

Adult↗

Effects of the herbal medicine "Sai-rei-to" on in vitro interferon-gamma production of peripheral blood mononuclear cells.

The herbal medicine "Sai-rei-to" has been used in the treatment of swellings and edemas for about 3000 years in China. Recently, this drug has been prescribed as an adjuvant in the treatment of rheumatoid arthritis (RA) among Japan's western medicine doctors. It is thought to possess regulatory effects on the immune system, although its mode of action is not yet fully described. In the present in vitro study, we at first induced interferon-gamma (IFN-gamma) in the cultures of peripheral blood mononuclear cells of healthy volunteers by adding pokeweed mitogen (PWM), phytohemagglutinin (PHA), recombinant interleukin-2 (IL-2), or control medium. We then added "Sai-rei-to" to these cultures and investigated the effects of this drug on IFN-gamma production levels. The results demonstrated that "Sai-rei-to" had 2 different effects: (i) it inhibited the IFN-gamma production in cultures with PWM or PHA (which induced large volumes of IFN-gamma), and (ii) it increased IFN-gamma production in the cultures with IL-2 (IL-2 induced only small volumes of IFN-gamma). These findings indicate that "Sai-rei-to" possesses regulatory effects on the IFN-gamma production. IFN-gamma is an important cytokine in the immune system, and it has also attracted attention as a factor related to the pathogeneses of RA. Therefore, concomitant administration of such a medicine which can appropriately control IFN-gamma production in vivo could be beneficial for RA patients from the immunological viewpoint. Clinical experience in the past has shown that "Sai-rei-to" has a very low incidence of side effects, and can be administered orally for long periods. We expect that concomitant administration of "Sai-rei-to" with current therapy could be clinically useful in the management of RA patients.

Arthritis, Rheumatoid↗

Herbal medicine "sho-saiko-to" induces in vitro granulocyte colony-stimulating factor production on peripheral blood mononuclear cells.

The herbal medicine "Sho-saiko-to (Xiao-Chai-Hu-Tang)" has been used in China for about 3000 years for the treatment of pyretic diseases. This medicine is now available as one of the prescribing drugs approved by the Ministry of Health and Welfare of Japan, and has also been widely used for patients with chronic viral liver disease as one of biological response modifiers in the field of Japan's Western Medicine. However, its mode of action has not been fully described. In the present in vitro study, we added "Sho-saiko-to" (TJ-9, Tsumura, Tokyo) to the culture of peripheral blood mononuclear cells (PBMC) obtained from healthy volunteers, and observed a dose-dependent increase in the production of granulocyte colony-stimulating factor (G-CSF). The same experiment was conducted using other herbal medicines "Dai-saiko-to" (TJ-8) and "Saiko-keishi-to" (TJ-10) which showed similar effects, or "Sho-seiryu-to" (TJ-19) which consists of very different compounds and shows different efficacy. The increases of G-CSF production were similar when "Sho-saiko-to" (TJ-9) or one of the 2 reference drugs (TJ-8 and 10) was added, whereas the increase when the control drug "Sho-seiryu-to" (TJ-19) was added, was quite small. This result shows that G-CSF induction is not a common effect of herbal medicines, but a specific effect of TJ-8, 9, and 10. Among these 3 drugs the increase produced by "Sho-saiko-to" was the largest. Based on this result, we conclude that administration of "Sho-saiko-to" may be useful not only for the treatment of chronic liver disease, but also for malignant diseases and acute infectious diseases where G-CSF is efficacious.

Anti-Inflammatory Agents, Non-Steroidal↗

Effects of methylcobalamin (vitamin B12) on in vitro cytokine production of peripheral blood mononuclear cells.

Recently in Japan, one form of vitamin B12, methylcobalamin also known as methyl B12, has attracted the attention of physicians as a therapy for patients with rheumatoid arthritis. However, its immunological actions in vivo are still unknown. In this study, we induced the in vitro production of such cytokines as interleukin-6 (IL-6), interferon-gamma (IFN-gamma), and interleukin-1 beta (IL-1 beta) by adding various mitogens (phytohemagglutinin:PHA, concanavalin A: ConA, or pokeweed mitogen:PWM) as well as recombinant interleukin-2, and we investigated the effects of methyl B12 (final concentration, 8-8,000 ng/ml) on the production of these cytokines by peripheral mononuclear cells. As compared to the controls, IL-6 production induced by PHA and ConA on Day 4 of the culture was suppressed by an average 60-70% when methyl B12 (80-8,000 ng/ml) was added to the medium. IFN-gamma production decreased dose-dependently with methyl B12, i.e., it decreased to 46% of the control when this production was induced by rIL-2, and decreased to 56-66% when it was induced by mitogens. The effect of methyl B12 on IL-1 beta production on Day I of the culture was small. These findings indicate that methyl B12 suppresses mainly the cytokine production of T lymphocytes. Such suppressive effects as shown in the in vitro situation are expected to be expressed also in vivo in patients with rheumatoid arthritis, especially at articulation lesion sites.

Arthritis, Rheumatoid↗

Efficacy of a herbal medicine "sho-saiko-to" on the improvement of impaired cytokine production of peripheral blood mononuclear cells in patients with chronic viral hepatitis.

Peripheral blood samples were collected from normal subjects and chronic viral hepatitis patients, and the in vitro capability of the peripheral blood mononuclear cells to produce various cytokine (interleukin-1 beta, interleukin-6, interferon-gamma, and granulocyte-macrophage colony-stimulating factor) were analyzed by adding pokeweed mitogen. We then investigated the effects of a herbal medicine "Sho-saiko-to" on the levels of cytokine production. The production levels of the 4 cytokines were significantly lower in the peripheral blood mononuclear cells of the patients (Patient Group) than in those of normal subjects (Control Group). The addition of Sho-saiko-to to the Patient Group resulted in improved productions of those cytokines, as well as an remarkable improvement of interleukin-1 beta production. The results demonstrated that Sho-saiko-to acts to improve such immunological abnormalities as decreased cytokine productions. Administration of Sho-saiko-to to chronic viral hepatitis patients is also expected to have immunological benefits.

Anti-Inflammatory Agents, Non-Steroidal↗

Effects of the streptococcal preparation OK-432 on in vitro cytokine production of peripheral blood mononuclear cells in patients with chronic viral hepatitis.

We obtained peripheral blood mononuclear cells from 12 chronic hepatitis Type B patients, 12 Type C patients, and 15 healthy volunteers, and investigated the effects of OK-432, a streptococcal preparation, on in vitro production of 3 types of cytokines. Mononuclear cells in a concentration of 1 x 10(6) cell/ml were prepared in the culture medium. OK-432 (Chugai Pharmaceutical Co., Ltd., Tokyo) was added to this preparation and incubated for one to 4 days. Thereafter interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and interferon-gamma (IFN-gamma) levels in the culture supernatant were measured using enzyme-linked immunoassay kits. Cytokine production levels in cultures with OK-432 were significantly increased in the mononuclear cells of both patients and healthy volunteers. The largest increase was observed with IFN-gamma (p < 0.01), and then with IL-1 beta (p < 0.05). Responses of the cells from chronic hepatitis Type C patients to OK-432 were relatively good. When interferon (alpha and beta) treatment was first introduced, there were high hopes for a high efficacy. However, we now know 50-70% of patients with chronic hepatitis Type C do not respond satisfactorily to interferon. Some physicians suggest the necessity of using biological response modifier (BRM) as an adjuvant treatment for these patients. From our findings, OK-432 could be a useful BRM in patients with chronic hepatitis Type C.

Cells, Cultured↗

[A case of pneumonitis and hepatic injury caused by a herbal drug (sho-saiko-to)].

We report a case of pneumonitis and hepatic injury caused by Sho-saiko-to. A 56-year-old man was admitted to our hospital because of hepatic disorder. The levels of serum transaminases returned to normal within two months without specific treatment and he was discharged. Four weeks later, he was readmitted because of severe pneumonitis and mild hepatic disorder. Under the suspicion of drug-induced pneumonitis, all medications were discontinued and high-dose glucocorticoid including "pulse therapy" was given. Consequently, pneumonitis and hepatic function markedly improved. Careful history taking revealed the ingestion of Sho-saiko-to before both admissions. Lymphocyte stimulation test against Sho-saiko-to was positive. Challenge test using Sho-saiko-to resulted in decrease of PaO2 and elevation of serum transaminases. Based on these findings, the diagnosis of pneumonitis and hepatic injury induced by Sho-saiko-to was established.

Alveolitis, Extrinsic Allergic↗

[Effects of prostaglandin E1 and epidural block on circulatory, hepatic and renal functions during anesthesia for major upper abdominal surgeries].

The effects of low dose (0.02 microgram.kg-1.min-1) prostaglandin E1 (PGE1), epidural block (EP) or combination of PGE1 and EP (PGE1 + EP) under general anesthesia on circulatory, hepatic and renal functions were studied in 31 patients undergoing major upper abdominal surgeries without hepatic or renal dysfunction preoperatively. Mean arterial pressure decreased by 10% in PGE1 and EP groups, while 20% in PGE1 + EP group. Cardiac output decreased significantly in EP group, increased in PGE1 group and was unaltered in PGE1 + EP group during anesthesia and the operation. The arterial ketone body ratio as a hepatic function test increased following the administration of PGE1 or epidural block. Urine output, osmotic clearance and free water clearance were higher in PGE1 + EP group during the operation. These results suggest that the combination of low dose PGE1 and epidural block maintain cardiac output and organ blood flow during anesthesia and surgery in spite of a greater decrease in arterial blood pressure.

Abdomen↗

A case of acute intermittent porphyria with acute pancreatitis.

A case of acute pancreatitis in a 29-year-old female associated with an attack of acute intermittent porphyria (AIP) is reported. Following the attack of AIP, serum pancreatic amylase originating from the pancreas increased transiently, and mild swelling of the pancreas was detected by ultrasonography. On this basis acute pancreatitis was diagnosed. Additionally, this patient had mild hepatic dysfunction. Laparoscopy disclosed diffuse slightly dark bluish pigmentation on the irregular surface of the liver. Mild fibrous dilatation of the portal area with lymphocytic infiltration was seen histologically. Acute pancreatitis and hepatic damage with AIP is extremely rare, however it is possible that these findings are etiologically connected in this patient.

Acute Disease↗

Effects of abdominal surgery on somatosensory evoked potentials during nitrous oxide-enflurane anesthesia.

The effect of abdominal surgery on median nerve somatosensory evoked potentials (SEPs) was studied in 8 enflurane and nitrous oxide anesthesia (GOE) patients. We further compared the effect of epidural anesthesia. The first recording was done immediately prior to induction. Anesthesia was then induced with 5 mg.kg(-1) i.v. of thiopental and maintained with 1.0% enflurane, 66% N(2)O and 33% O(2). Before skin incision for abdominal surgery, the second recording was performed under GOE anesthesia and the third recording during surgery. Then 2% lidocaine was injected into the epidural space through a preinserted catheter, and after 15 min the fourth recording was obtained. The latencies of peaks N1, P2 and N2 and the amplitudes of N1-P2 and P2-N2 were measured. The latencies of N1, P2 and N2 increased and the amplitudes of N1-P2 and P2-N2 deceased significantly after the induction of anesthesia compared with the control values. During abdominal surgery the latencies of N1 and P2 decreased and the amplitudes of N1-P2 and P2-N2 increased. After epidural anesthesia, however, the latencies of N1 and P2 increased and the amplitudes of N1-P2 and P2-N2 decreased significantly and returned almost to the values recorded under preoperative GOE anesthesia. These phenomena indicated that the excitations produced by surgical stimulation in nerve ending might have been transmitted to the central nervous system via spinal nerves and blocked by epidural anesthesia.

Journal Article↗