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Biomedical subjects

Y Kosaka

Publications and source records attributed to Y Kosaka.

At least 73 records · Page 4Linked to original sources
PubMed1998

The advantages of the lateral decubitus position after spinal anesthesia with hyperbaric tetracaine.

UNLABELLED: We investigated the effects of lateral decubitus positioning after spinal anesthesia with hyperbaric tetracaine on the spread of sensory blockade and hemodynamic variables. One hundred ASA physical status I or II patients scheduled for elective surgery to the lower limb received spinal anesthesia at a rate of approximately 0.1 mL/s using 0.5% tetracaine in 7.5% glucose with 0.125% phenylephrine in the lateral decubitus position with the operated side dependent. They were randomly divided into three groups: patients in Group I were placed supine immediately after spinal injection; those in Group II remained in the lateral position for 10 min before being turned supine; those in Group III were kept in the lateral position for 20 min then turned supine. Neural block was assessed by cold, pinprick, and touch sensation, and a modified Bromage scale. Hemodynamic variables included blood pressure, heart rate, and the use of ephedrine for the treatment of hypotension. The median (10th, 90th percentiles) peak dermatomal level to pinprick on the dependent side in Group III was T8 (T11, T5), which was significantly lower than that in Groups I and II, which extended to T4 (T9, T3) and T5 (T10, T2), respectively (P < 0.05). The difference in the maximal cephalad spread of sensory blockade between both sides in Group III was only one dermatome but was statistically significant (P < 0.05); in contrast, there was no significant difference in the maximal sensory level between both sides in Groups I and II. The use of ephedrine for the treatment of hypotension was significantly less frequent in Group III than the other groups. We conclude that keeping a patient in the lateral decubitus position for 20 min after hyperbaric tetracaine spinal anesthesia maintains preferential anesthetic distribution to the dependent side. Despite small differences between the two sides, the restricted spread of blockade and less hemodynamic variability may be clinically advantageous. IMPLICATIONS: The effects of posture on the spread of hyperbaric spinal anesthesia have not been adequately investigated. The results of the present study suggest an advantage of prolonged lateral decubitus positioning after intrathecal hyperbaric tetracaine.

Adolescent↗
PubMed1998

Characteristics of tolerance to somatic and visceral antinociception after continuous epidural infusion of morphine in rats.

UNLABELLED: A continuous epidural infusion of morphine may cause a complicated tolerance to develop, depending on the spinal and supraspinal sites. We designed this study to clarify the characteristics of the tolerance to somatic and visceral antinociception after epidural morphine infusion. Rats received epidural infusion of morphine at the rates of 50 or 100 microg kg(-1) h(-1), or isotonic sodium chloride solution for 7 days. The tail-flick (TF) test and colorectal distension (CD) test were used to measure the somatic and visceral antinociceptive effects, respectively. Nociceptive tests were performed on Days 1, 2, 3, 4, and 7. After 7 days, time-response curves after epidural morphine (10 microg) or intraperitoneal morphine (3 mg) challenge tests were conducted to assess the magnitude of tolerance. Epidurally infused morphine significantly increased percent maximal possible effects (%MPEs) (P < 0.05) in both the TF and CD tests, depending on the concentration of morphine. In the epidural morphine challenge test, increases in %MPEs were significantly attenuated (P < 0.05) in the morphine-infused group compared with the isotonic sodium chloride solution-infused group. The increases in %MPEs in the intraperitoneal challenge test were also attenuated in the morphine-infused group. We conclude that morphine tolerance to both somatic and visceral antinociception develops rapidly during epidural infusion and is based on the development of tolerance at the systemic, as well as the epidural, level. IMPLICATIONS: A continuous epidural infusion of morphine rapidly induces tolerance to visceral and somatic antinociception in rats. This development is based on the development of tolerance at the systemic, as well as the epidural, level.

Analgesics, Opioid↗
PubMed1997

Regional cerebral glucose utilization is modulated by the dosage of apolipoprotein E type 4 allele and alpha1-antichymotrypsin type A allele in Alzheimer's disease.

Twenty Alzheimer's disease (AD) patients with defined apolipoprotein E (APOE), alpha1-antichymotrypsin (ACT) and presenilin-1 (PS-1) intronic genotypes were examined to quantify the regional cerebral metabolic rate of glucose (rCMRglc) using positron emission tomography (PET) and 18F-2-fluoro-2-deoxy-D-glucose (FDG). The frontal rCMRglc was significantly increased in patients with the APOE epsilon4 allele in a dose-dependent fashion. In contrast, the temporo-parietal rCMRglc was significantly reduced in ACT type A allele (ACT*A) carriers compared with those in non-ACT*A carriers. The PS-1 type 1 intronic allele had no significant effects on rCMRglc in any cerebral region. These results suggest that both the APOE and ACT genes may play a distinct role in the progression of AD as monitored by imaging studies of cerebral glucose utilization.

Aged↗
PubMed1997

Assembly and regulation of the CD40 receptor complex in human B cells.

CD40 is a member of the tumor necrosis factor (TNF) receptor superfamily. Studies with human B cells show that the binding of CD154 (gp39, CD40L) to CD40 recruits TNF receptor- associated factor 2 (TRAF2) and TRAF3 to the receptor complex, induces the downregulation of the nonreceptor-associated TRAFs in the cell and induces an increased expression of Fas on the cell surface. Combined signaling through the interluekin 4 receptor and CD40 induces an increased expression of Fas with a commensurate increase in the level of TRAF2, but not TRAF3, that is recruited to the receptor complex. In contrast, engagement of the membrane immunoglobulin and CD40 limits Fas upregulation and reduces the recruitment of TRAF2, relative to TRAF3, to the CD40 receptor complex. These studies show that the TRAF composition of the CD40 receptor complex can be altered by signals that influence B cell differentiation.

B-Lymphocytes↗
PubMed1997

Effects of the Japanese herbal medicine "Sho-saiko-to" (TJ-9) on in vitro interleukin-10 production by peripheral blood mononuclear cells of patients with chronic hepatitis C.

"Sho-saiko-to" (TJ-9) consists of 7 herbal components. In Japan, it is widely prescribed to patients with chronic viral liver disease. TJ-9 is known to suppress liver cancer development and possess macrobiotic effects, but its mode of action is not fully understood. This study investigated the following: 1) cytokine production levels, mainly interleukin (IL)-10, in peripheral blood mononuclear cells of chronic active hepatitis B and C patients, and healthy volunteers; 2) effects of TJ-9 on these productions; and 3) effects of each of its herb components on cytokine production in cell fractions. Results showed that without stimulants, IL-10 production in mononuclear cells of hepatitis B and C patients was significantly lower than that of healthy subjects (P < .01). IL-10 production induced by either phytohemagglutinin (PHA) or pokeweed mitogen (PWM) in mononuclear cells of hepatitis C patients were significantly lower than in patients with hepatitis B (P < .01) and healthy subjects (P < .05). IL-10 production induced by anti-CD3 or lipopolysaccharide (LPS) was significantly lower than in healthy subjects (P < .05). The addition of TJ-9 to the cultures strongly induced IL-10, and this induction was mainly attributable to the effects of 2 components (scutellaria root and glycyrrhiza root) on the monocyte/macrophage fraction. The production of IL-4 and IL-5 in cultures with concanavalin A (conA) was significantly higher in patients with hepatitis C than in the healthy subjects (P < .01; P < .05), but the addition of TJ-9 suppressed these increases by 25% to 33% (P < .01). Therefore, TJ-9 could adjust the decreased IL-10 production and the increased IL-4 and IL-5 production of mononuclear cells from patients with hepatitis C. Moderate regulation of the cytokine production system in patients with hepatitis C by using TJ-9 may be useful in the prevention of disease progression.

Adult↗
PubMed1997

In vitro effects of sho-saiko-to on production of granulocyte colony-stimulating factor by mononuclear cells from patients with chronic hepatitis C.

During the past 2 years, drug-induced interstitial pneumonia was reported in 66 Japanese patients, mainly among chronic hepatitis C patients, undergoing treatment with the Japanese herbal medicine "Sho-saiko-to" (TJ-9). As interstitial pneumonia is also induced by granulocyte colony-stimulating factor (G-CSF), we examined the effects of TJ-9 on G-CSF production in peripheral blood mononuclear cells. In patients with hepatitis B or C, G-CSF production in the absence of any stimulation was significantly lower than healthy controls (p < 0.01). G-CSF production increased along with the increase of TJ-9 levels, and this could induce excessive production of G-CSF in hepatitis C patients, and this may be a cause of interstitial pneumonia.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1997

An effective intradermal hepatitis B vaccination.

Small dose intradermal (i.d.) inoculation methods of hepatitis B vaccine have been reported to be effective and economical. We determined the best method to obtain high antibody levels within a short period of time and for the long-term maintenance of these levels. A total of 173 female students were randomly allocated to seven groups: six i.d. inoculation groups, to which 6-12 micrograms was administered in three or four divided doses (Groups A-F), and a control group (Group G) which received three 10 micrograms intramuscular (i.m.) inoculations. Serum hepatitis B antibody levels were quantified in weeks 4 and 8, and months 4, 7, and 12. Positivities in all groups were not significantly different at each measurement time. In month 4, geometric mean antibody levels in the three i.d. groups (10-12 micrograms in three divided doses; 79.1-107.0 IU l-1) were significantly higher than in Group G, which had received two of three i.m. injections (17.6 IU l-1; P < 0.01, P < 0.05). In the group which received four 2 micrograms i.d. inoculations, the level was higher than in Group G in month 7, but lower in month 12. It was concluded that three i.d. inoculations, each of 4 micrograms, may be used to obtain high antibody levels within a short period of time. However, it is recommended that a 10 micrograms i.m. injection in month 6 is applied as a booster. Consequently, we could not present an economic and effective low-dose intradermal inoculation method.

Administration, Cutaneous↗
PubMed1997

The addition of phenylephrine contributes to the development of transient neurologic symptoms after spinal anesthesia with 0.5% tetracaine.

BACKGROUND: Recent reports indicate that transient neurologic symptoms commonly occur after single-injection spinal anesthesia with lidocaine. Information regarding tetracaine has been limited to a single case report. In addition, little is known about the cause of these symptoms or the cofactors that affect their occurrence. The present study sought to determine whether the presence of phenylephrine or the concentration of glucose in the anesthetic solution affects the incidence of transient neurologic symptoms after spinal anesthesia with 0.5% tetracaine. METHODS: One-hundred sixty patients classified as American Society of Anesthesiologists physical status I or II who were scheduled for elective surgery on a lower limb or perineum were sequentially assigned to one of four equal groups to receive intrathecal 0.5% tetracaine in 7.5% or 0.75% glucose, with or without 0.125% phenylephrine. Patients were evaluated on postoperative day one for the presence of pain, dysesthesia, or both in the legs or buttocks by an investigator unaware of the drug given. RESULTS: Symptoms were present in 10 patients (12.5%) receiving a spinal anesthetic containing phenylephrine, but in only one patient (1.3%) receiving spinal anesthesia without phenylephrine. There was no significant difference in the incidence of symptoms between groups receiving 7.5% glucose and those receiving 0.75% glucose (8.8% and 5% of patients, respectively). CONCLUSIONS: These results suggest that adding phenylephrine to tetracaine for spinal anesthesia increases the potential for transient neurologic symptoms, but that the concentration of glucose does not affect their occurrence.

Adult↗
PubMed1997

[Anesthetic management using transesophageal echocardiography during removal of a cardiac myxoma].

Removal of a cardiac myxoma can be complicated by mitral stenosis, arterial embolism and so on, all of which may be life-threatening but difficult to diagnose. We describe the use of transesophageal echocardiography (TEE) for the anesthetic management of two patients undergoing removal of a large myxoma in the left atrium (LA). The first case is a 78-yr-old woman, who was suffering from cardiac cachexy with a large LA myxoma. The anesthetic management of her surgery required the prevention of a decrease in cardiac output caused by anesthetic agents, massive bleeding and surgical procedures. The second case is an asymptomatic 60-yr-old man with LA myxoma, which appeared adherent to the mitral orifice in diastole. The goal of the anesthetic management of him was to prevent the obstruction of transmitral blood flow caused by the decrease in preload on the heart. Throughout the surgeries, TEE monitoring was conducted and helped decide the doses and/or rate of inotropes and vasodilators as well as the transfusion of fluid and blood to obtain stable circulatory conditions. It was also found to be of considerable value in understanding the pathophysiology of the tumors in LA. In conclusion, TEE monitoring during the surgery can be of much use both in the diagnosis and the anesthetic management of a patient with a large LA myxoma.

Aged↗
PubMed1997

[Postoperative brain infarction in a patient with the previous asymptomatic brain infarction].

We report a case of a postoperative brain infarction, in which an asymptomatic preoperative brain infarction was also revealed postoperatively. A 63-year-old man with bladder carcinoma was scheduled for the cystoplasty. The patient had no prominent preoperative abnormality. Anesthesia was maintained with isoflurane in N2O/oxygen combined with a spinal block and a continuous epidural block. Anesthesia lasted uneventfully for 16.5 hours. However, emergence from anesthesia was delayed. On the first postoperative day, motor aphasia and right hemiparalysis was confirmed. The computed tomography (CT) of the brain demonstrated a low density area in the frontoparietal region. The magnetic resonance imaging (MRI) indicated the corresponding lesion as the CT had demonstrated, and an old brain infarction in the parietal region. This meant that the patient had a history of asymptomatic brain infarction (ABI). Patients with ABI are considered to be a high-risk group for a brain infarction. It is important to evaluate the risk factors of brain infarction preoperatively and to minimize those risks during the operation. Maintenance of the cerebral perfusion pressure is imperative.

Anesthesia, Epidural↗
PubMed1997

[A patient with acromegalic heart disease--a case report].

A perioperative anesthetic management of a 69 year old woman with acromegaly whose clinical course was characterized by severe heart failure is described. The patient showed symptoms of massive cardiomegaly. Endocrine studies indicated that her pituitary tumor was active with hyperproduction of growth hormone. There was no demonstrable evidence for other known causes of heart disease. Following hormonal therapy using continuous subcutaneous infusion of somatostatin for about two months, there was improvement in daily activity and reduction in heart size. After the improvement of cardiac function, transsphenoidal hypophysectomy was performed under general anesthesia and its perioperative course was quite uneventful. We conclude that because cardiac involvement such as left ventricular dilatation in acromegaly might be reversible with proper treatment, any surgical procedure, as long as the case is elective, should be considered after hormone therapy.

Acromegaly↗
PubMed1997

[A malpositioned CVP catheter].

A 2-year-old boy was scheduled for patch closures of ASD and VSD. After anesthesia induction, infection of a double lumen central venous catheter (5 Fr, Arrow) was tried into the superior vena cava through the right jugular vein by Seldinger's method. We confirmed the placement of the catheter by drawing a small amount of blood. After the operation, chest X-ray examination in ICU revealed the misplacement of the catheter into his right intrapleural space. The catheter was left overnight to be used as a drainage route of a possible bleeding. Next morning, no abnormal finding in his chest X-ray and stable circulatory and respiratory conditions were found and we proceeded to extubate his endotracheal tube and take away the catheter. Two hours after the removal of the catheter, the boy showed forced respiration. He became cyanotic rapidly and then he needed emergency intubation. Following chest X-ray examination and an aspiration of intrapleural space revealed a severe hemothorax of the right side, where catheter had been inserted. The boy recovered without any disorders. This case suggests the importance to confirm the placement of CVP catheter, and to prevent the possible complications due to the malpositioned catheter.

Anesthesia, General↗
PubMed1997

[Regional difference in the etiology of liver cirrhosis in Iwate].

To assess regional differences in the etiology of liver cirrhosis in Iwate, we analyzed 324 patients with liver cirrhosis treated at various hospitals. The etiology was HCV 44.8%, HBV 11.1%, HBV + HCV 4.6%, alcohol 27.5% (including heavy drinkers 17.9%), PBC 1.5% and non-B non-C 10.5% in Iwate. The incidence of alcoholic cirrhosis was higher than that in other prefectures, while that of HCV was lower. Especially in the northern area of Iwate, the rate of alcoholic cirrhosis was very high (39.1%--including heavy drinkers 21.8%) while viral cirrhosis was relatively low. Although the alcohol consumption volume in Iwate was not very high, marked alcohol consumption, especially shochu, was observed in the northern area of Iwate. The volume and kind of alcohol consumed in each area differed, and the etiology of liver cirrhosis differed regionally in Iwate. Thus, we should consider these districts and levels of alcohol consumption when treating patients with liver cirrhosis.

Female↗
PubMed1996

Antinociceptive effects of epidural and intravenous ketamine to somatic and visceral stimuli in rats.

PURPOSE: To evaluate the antinociceptive effect of epidural and intravenous ketamine on somatic and visceral stimuli and to address the emergency reaction. METHODS: Rats were randomly allocated into nine groups (n = 6); five groups with chronically implanted epidural catheters received saline or 0.5, 1, 2 and 4 mg. kg-1 ketamine epidurally, four groups received saline, or 1, 5 and 10 mg. kg-1 ketamine i.v. To assess somatic and visceral antinociceptive effects, tail flick (TF) test and colorectal distension (CD) test were carried out, respectively. Emergence reactions were graded. Maximal possible effects (% MPE) were calculated. RESULTS: Epidural ketamine increased % MPE in both tests in a dose-dependent fashion for 30 min (vs saline group, P < 0.05). Epidural ketamine 0.5 mg. kg-1 produced an increase in % MPE in the CD test (P < 0.05) but failed in the TF test. Intravenous ketamine, 10 mg. kg-1, produced 100 +/- 0 (mean +/- SE) % MPE in the CD test but 36 +/- 15% MPE in the TF test. Dose response curves indicated greater visceral antinociception than somatic. All rats showed emergence reactions following intravenous ketamine 10 and 5 mg. kg-1. CONCLUSION: Both epidural and intravenous ketamine produce greater antinociceptive effects to visceral than to somatic stimulation, and that epidural ketamine has a low incidence of emergence reactions.

Analgesics, Non-Narcotic↗
PubMed1996

Comparison of glucose 7.5% and 0.75% with or without phenylephrine for tetracaine spinal anaesthesia.

PURPOSE: To investigate whether a marginally hyperbaric tetracaine solution with or without phenylephrine could produce consistent blocks as compared with a conventionally hyperbaric tetracaine solution injected at L3-4 interspace with the patient in the lateral position. METHODS: We studied 120 ASA I or II patients scheduled for elective surgery to the lower limb. Patients were randomly divided into four equal groups to receive spinal anaesthesia using tetracaine 0.5% in glucose 0.75% or 7.5%, with or without phenylephrine 0.125%. Neural block was assessed in a double-blind manner by cold, pinprick, and touch sensation, and a modified Bromage scale after the injection of the study drug. RESULTS: The median (10th, 90th percentiles) peak dermatomal level to pinprick obtained by the solutions in glucose 0.75% was T10 (L1, T5), which was lower than that obtained by the solution in glucose 7.5% extending to T5 (T10, T3) and T5 (T10, T2) with or without phenylephrine, respectively (P < 0.0001). The addition of phenylephrine prolonged the time to two-segment regression but did not change the maximum extent of blocks. CONCLUSIONS: A marginally hyperbaric tetracaine with or without phenylephrine produced consistent blocks with spread restricted to the lower thoracic segments when administered intrathecally at the L3-4 interspace with the patient in the lateral position.

Adult↗