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Biomedical subjects

R Shimizu

Publications and source records attributed to R Shimizu.

At least 109 records · Page 6Linked to original sources
PubMed1996

Effects of thoracic vs. lumbar epidural anaesthesia on systemic haemodynamics and coronary circulation in sevoflurane anaesthetized dogs.

BACKGROUND: Although many investigators reported changes in coronary circulation during thoracic epidural anaesthesia (TEA), no previous studies have attempted to compare it with lumbar epidural anaesthesia (LEA) concerning coronary circulation. Our aim was to compare effects of TEA on systemic haemodynamics and coronary circulation with those of LEA in anaesthetized dogs. METHODS: In dogs receiving 1.5% sevoflurane, 2% lidocaine (0.1 ml kg-1) was injected into the epidural space via an epidural catheter inserted at either the T7-T8 (TEA group, n = 8) or L5-L6 (LEA group, n = 8) interspace, and the same dose was repeated again 30 min later. RESULTS: Heart rate and maximum left ventricular dP/dt decreased in the TEA group but were unchanged in the LEA group. Decreases in mean arterial pressure were found for both groups, and they were more substantial in the TEA than in the LEA group. Decreases in left ventricular minute work index were found for both groups, and they tended to be more substantial in the TEA than in the LEA group. Coronary perfusion pressure and blood flow decreased in both groups. Calculated coronary vascular resistance increased in the TEA group but was unchanged in the LEA group. CONCLUSION: The most significant difference between TEA and LEA concerning coronary circulation was characterized by an increase in coronary vascular resistance in the TEA group, which was not present in the LEA group. The increase in coronary vascular resistance caused by TEA may be explained by a coronary vasoconstriction caused by a lower myocardial oxygen demand.

Anesthesia, Epidural↗
PubMed1996

Restriction fragment length polymorphisms of rDNA and variation of essential oil composition in Atractylodes plants.

Total DNA was extracted from the leaves of Atractylodes lancea DE CANDOLLE, A. ovata DE CANDOLLE and A. japonica KOIDZUMI ex KITAMURA of various origins and hybridized with digoxigenin-labeled rice ribosomal DNA after digestion with eight different restriction endonucleases. The resulting restriction fragment length polymorphism (RFLP) profiles allowed us to distinguish the three Atractylodes species when DNA was digested with Sac I. Although atractylon was detected in the rhizomes of some of the cultivated strains of A. lancea, their RFLP profiles clearly indicate that these plants are not hybrids of A. ovata or A. japonica. RFLP analysis also revealed the presence of intraspecific variation in DNA sequence of rRNA locus among A. lancea as well as A. japonica.

DNA Restriction Enzymes↗
PubMed1996

Effect of positive end-expiratory pressure on extravascular lung water and cardiopulmonary function in dogs with experimental severe hydrostatic pulmonary edema.

The effects of ventilation at positive end-expiratory pressure (PEEP) on extravascular lung water (EVLW) and cardiopulmonary function were studied in dogs with experimental severe hydrostatic pulmonary edema, which was generated by inflating a left atrial balloon and simultaneously injecting warm 5% glucose solution into the pulmonary artery. The EVLW was measured by the double indicator dilution method using heat and sodium ions. All the dogs were ventilated at zero end-expiratory pressure (ZEEP) until the EVLW had increased by 200-300% (maximal edema), when they were divided into two groups, one of which (n = 6) was ventilated at a PEEP of 10 cm H2O throughout the 4 hr study period (PEEP group) and the other (n = 6) was maintained at ZEEP during their survival period (ZEEP group). All the dogs in the PEEP group survived ventilation for 4 hr, whereas all those in the ZEEP group died within 3 hr, (2 within 1 hr, 1 between 1 and 2 hr and 3 between 2 and 3 hr). The EVLW of the PEEP group remained unchanged throughout the 4 hr study period, whereas that of the ZEEP group showed a tendency to increase. The arterial oxygen tension (PaO2) increased significantly throughout the 4 hr period of ventilation in the PEEP group but tended to decrease in the ZEEP group. In conclusion, PEEP improves gaseous exchange, but does not decrease the EVLW in dogs with experimental severe hydrostatic edema.

Analysis of Variance↗
PubMed1996

Radiographical evaluation of bone maturation in Japanese black beef cattle.

Epiphyseal ossification in the radius, ulna, metacarpus, proximal phalanx and tuber calcaneus was examined radiographically in Japanese Black beef cattle. The grade of standard ossification was assessed monthly for each epiphysis. Bone maturations could be divided into 8 grades for the distal radius and distal ulna, 7 grades for the distal metacarpus, 5 grades for the proximal phalanx, and 8 grades for the tuber calcaneus, respectively. The closure of the epiphyseal line completed at the earliest (12-14 months of age) on the proximal phalanx, and at the latest (35-37 months of age) on the distal ulna. Changes in gradings were steep at 0 to 5 months of age but became almost constant after 10 months of age in all the epiphyses. There were no significant differences in bone maturation between the cattle with different sex and breeding conditions.

Aging↗
PubMed1996

Effects of inhaled nitric oxide on hypoxic pulmonary vasoconstriction in dogs and a case report of venae cavae syndrome.

We investigated the effect of inhaled nitric oxide (NO) on hypoxic pulmonary vasoconstriction (HPV) in dogs, by treating a dog suffering from venae cavea syndrome (VCS) and pulmonary hypertension (PH) with NO inhalation. The increasing mean pulmonary arterial pressure (mPAP) induced by hypoxia was lessened significantly by NO inhalation. High PAP in VCS also declined as a result of NO inhalation. These results suggested that inhaled NO can reverse HPV in dogs and prevent worsening PH during surgical extraction of heartworm in VCS.

Administration, Inhalation↗
PubMed1996

Evaluation of pulmonary vasodilatory capacity with inhaled nitric oxide in a dog with patent ductus arteriosus.

A female Maltese dog with patent ductus arteriosus (PDA) showing left congestive heart failure and moderate pulmonary hypertension was evaluated for pulmonary vasodilatory capacity using low concentrations of inhaled nitric oxide (NO) in comparison with oxygen during preoperative cardiac catheterization. Increasing the inspired oxygen concentration (FiO2) to 1.0 without adding NO did not reduce the mean pulmonary arterial pressure (mPAP). However, inhalation of NO at FiO2 1.0 reduced mPAP rapidly without changing other hemodynamic and gas exchange parameters. From these results, inhaled NO caused selective pulmonary vasodilation without producing systemic vasodilation, which may provide a safe and effective mean of evaluating the pulmonary vasodilatory capacity of dogs with PDA.

Administration, Inhalation↗
PubMed1996

[Retrospective analysis on 21 patients with follicular lymphoma].

We retrospectively analyzed the clinical data of the 21 patients with follicular lymphoma admitted to our institution from 1977 to 1994. The frequency of follicular lymphoma was 9.1% in the 231 patients with non-Hodgkin's lymphoma. Overall survival rates at 1 year, 3 years, and 5 years were 90.2%, 78.2%, and 52.1%, respectively. The median follow-up of surviving patients and time to treatment failure (TTF) was 43 months and 30 months, respectively. The median time from disease progression to death was 171 days. In univariate analysis, factors associated with poor survival were stage IV (Ann Arbor staging system), anemia (hemoglobin level less than 10g/dl), bone marrow involvement, two or more extranodal sites, and failure in induction of complete remission (CR) in the entire course. Factors associated with short TTF were anemia, bone marrow involvement, and failure in induction of CR. In multivariate analysis, induction of CR affected survival and TTF independently.

Adult↗
PubMed1996

[Emergency internal carotid artery ligation using near infrared spectroscopy].

We anesthetized a patient who received an emergency internal carotid artery ligation. Regional cerebral oxygen saturation (rSO2) was measured with near infrared spectroscopy (NIRS) during the whole anesthetic course. The sensor was placed on the left forehead of the patient. Decrease in blood pressure was reflected in the decrease in rSO2. The rSO2 was not altered by internal carotid ligation. However, cerebral infarction in the middle cerebral artery region, the onset of which remained unclear, was revealed postoperatively, regardless of a stable rSO2 during the operation. This monitor may provide useful information regarding the cerebral circulation during the operation in such a case as the present one, but this monitor reflects only the oxygenation of the region on which the sensor was placed. Thus, we should keep in mind the limitation in detecting cerebral dysfunction using NIRS.

Anesthesia, General↗
PubMed1996

[Clinical evaluation of a new programmable syringe infusion pump].

A new programmable syringe infusion pump, Auto Syringe Model AS 40 A, was evaluated for infusion of muscle relaxants, vasodilators and opioids in 4 surgical patients. Every drug mentioned above was easily adjusted according to surgical requirement in these patients. Auto Syringe Model AS40A is light and compact. Its major advantages lie in the mechanisms for delivery of a bolus dose and automated delivery of intermittent doses, automatic rate calculation, and the applicability to various sizes of syringes. Auto Syringe Model AS40A was found to be very useful for intravenous infusion of drugs.

Adult↗
PubMed1996

[Cesarean section in a morbidly obese parturient under epidural anesthesia].

A 26-yr-old morbidly obese parturient with a body mass index of 62 kg.m-2 underwent elective cesarean section for preeclampsia under epidural anesthesia. The distance between the skin and the epidural space was about 9 cm at the L3-4 interspace via mid approach. Epidural catheter was inserted 5 cm cephalad in the sitting position and a bolus of 17 ml of mepivacaine 1.5% was given in the supine position. The T5 level of analgesia was obtained 10 min later. Forty minutes after the start of the surgery, a female newborn weighing 3,206 g was delivered with an Apgar score 8 at 1 min and 9 at 5 min. Throughout the surgery, sufficient analgesia was obtained and any complications such as severe hypotension and respiratory depression did not develop. Postoperative pain was relieved sufficiently with a continuous epidural infusion of 0.25% bupivacaine at a rate of 0.5 ml.h-1 for two days. Both maternal and neonatal postpartum courses were uneventful. In conclusion, elective cesarean section in a morbidly obese parturient was successfully managed with epidural anesthesia. This indicates that an elective cesarean section under epidural anesthesia reduce the risk of perioperative complications in a morbidly obese parturient.

Adult↗
PubMed1995

[Psychological evaluation of out-patients in our pain clinic using self-rating depression scale and state-trate anxiety inventory questionnaire].

In 98 out-patients who visited our pain clinic, we evaluated their psychological status before the first examination and one month after the treatment, using self-rating depression scale (SDS) and state-trate anxiety inventory (STAI). SDS, state anxiety, and trate anxiety scores were significantly higher in the patients with pain (trigeminal neuralgia, neck-shoulder-arm pain syndrome, lumbago and psychological pain, n = 55) compared with the patients without pain (sudden deafness and facial nerve palsy, n = 43) (P < 0.01, 0.05, 0.01). Of the patients with pain, patients with psychogenic pain showed the highest score in every test. The scores of SDS and state anxiety became significantly lower one month after the treatments compared with ones before the first examination (P < 0.01). It was considered that the decline in every score was due to the treatments in our pain clinic. In patients whose score of trate anxiety before the first examination was more than 50 points, the SDS and state anxiety showed high scores even one month after the treatments. This finding suggests that these patients need psychosomatic managements.

Adult↗
PubMed1995

[Reevaluation of hypothermia as protective measures against cerebral ischemia].

Two patients underwent carotid artery ligation for the purpose of surgical hemostasis either under hypothermia or under normothermia. One was 56-year-old man with rupture of brachiocephalic artery following esophagectomy. The bilateral common carotid arteries were ligated for bypass-grafting between the right internal carotid artery and the left common carotid artery for 35 min under surface-induced hypothermia at a rectal temperature of 30.7 degrees C. No postoperative neurological deficit developed. The other was 40-year-old woman with a malignant parotid tumor involving left internal carotid artery. The left carotid artery was ligated for 20 min at a rectal temperature of 37.3 degrees C. Cerebral ischemia developed postoperatively. Mild to moderate hypothermia should be reevaluated as one of useful measures to protect the brain from cerebral ischemia.

Adult↗
PubMed1995

Role of nitric oxide in anaphylactic shock.

Nitric oxide, synthesized from the guanidino group of L-arginine by nitric oxide synthase, has an important role in pathophysiological changes associated with anaphylaxis. Nitric oxide production due to activation of constitutive nitric oxide synthase is detected using a nitric oxide-selective electrode in anaphylactic rabbits in vivo. A nitric oxide synthase inhibitor attenuates hypotension and hemoconcentration and decreases venous return but does not improve cardiac depression. Nitric oxide functionally antagonizes the effects of vasoconstrictors released by anaphylaxis in vitro. In animals pretreated with a nitric oxide synthase inhibitor, the cardiac output falls significantly, although venous return is increased. Pulmonary resistance is significantly increased with a nitric oxide synthase inhibitor, and L-arginine attenuates the bronchospasm. These findings suggest that production of nitric oxide may reduce the pathophysiologic changes, except for vasodilatation, associated with anaphylaxis.

Anaphylaxis↗
PubMed1995

Combination chemotherapy of carboplatin and cytosine arabinoside for high-risk leukemia: a pilot study.

Fourteen patients with high-risk leukemia (six with relapsed AML, three with relapsed ALL, one with AML-M0, four with CML in myeloid blastic crisis) were treated with a combination chemotherapy of carboplatin (200-300 mg/m2/day) and cytosine arabinoside (100 mg/m2/day) by 24 h continuous infusion for 5-7 days. Five patients (35.7%) achieved complete remission including two patients complicated with myelofibrosis (one with AML-M0 and one with CML in myelo-megakaryocytic crisis). Thirteen patients had nausea and vomiting, five patients had severe, prolonged neutropenia for which it was necessary to administer granulocyte colony-stimulating factor and six patients had severe thrombocytopenia. We concluded that this regimen is effective for the treatment of high-risk leukemia.

Adolescent↗
PubMed1995

Suppressive effects of volatile anesthetics on cytokine release in human peripheral blood mononuclear cells.

This study investigated the effects of three volatile anesthetics (sevoflurane, isoflurane, and enflurane) on cytokine release by human peripheral mononuclear cells (PBMCs) stimulated by natural killer (NK)-sensitive tumor cells, K562, in vitro. PBMCs, as effector cells, obtained from 31 volunteers were randomly allocated to two groups in the first set of experiments. One group was incubated with K562 (n = 21) and the other with medium alone as a control (n = 10). In a second set of experiments, PBMCs from each volunteer (n = 21) were divided into three groups: nonanesthetic, 1.5-MAC, and 2.5-MAC groups (n = 7 for each anesthetic). After 2 h exposure to anesthetic gas or air, K562 cells were added to the effector cells. After 4 h incubation, interleukin-1 beta (IL-1 beta), interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-alpha), and interferon-alpha (INF-alpha) in the supernatant were assayed. IL-1 beta and TNF-alpha levels were significantly increased in comparison with those in the control group. IL-2 levels tended to be higher than those in the control group. No effect on IFN-alpha levels was found. After anesthetic exposure, the releases of IL-1 beta and the release of TNF-alpha were significantly inhibited compared with those after air exposure. None of the anesthetics inhibited IL-2 release. The anesthetics studied are capable of altering the release of cytokines by NK and NK-like cells in response to tumor cells.

Anesthetics, Inhalation↗
PubMed1995

Infrared angiography of the anterior ocular segment.

We performed angiography with indocyanine green (ICG) and fluorescein using a scanning laser ophthalmoscope (SLO) in the anterior segments of seven normal and 35 diseased eyes. ICG angiography revealed the radical stromal vessels and minor arterial circle in brown irides, which were not detected by fluorescein angiography. High penetration of infrared fluorescence through the pigmented tissue and absence of extravasation of ICG facilitated demonstration of the fine structure of iris rubeosis and its origins from stromal vessels. In 11 diabetic eyes, the iris rubeosis showed three basic patterns of location: along the pupillary margin; originating from the iris root; and arising from stromal radial vessels near the collarette. ICG gonioangiography with SLO showed fine structure of angle rubeosis because of its high resolution and greater depth in focus. Rubeotic vessels in the chamber angle were perfused by neovascular trunks which arose from the iris root in all 12 rubeotic eyes. Rubeosis in the iris and the angle consistently showed no extravasation of the ICG dye, while fluorescein quickly leaked out. ICG angiography with SLO in the anterior ocular segment proved to be a useful means to study the structure and the hemodynamics of normal and newly formed vessels.

Adult↗
PubMed1995

Spread of subarachnoid hyperbaric amethocaine in adolescents.

We have compared the spread of subarachnoid hyperbaric amethocaine in adolescents with that in adults. Amethocaine 8 mg in 2 ml of 10% glucose was injected through a 25-gauge spinal needle inserted at the L3-4 interspace in 21 adolescents aged 12-16 yr and in 111 adults aged 17-82 yr. Although we found no differences in height, weight or body mass index between the adolescents and adults, maximum spread of analgesia was significantly higher in the adolescents (median T3 (range T4-C5) than in the adults (T4 (T9-C7)). We conclude that subarachnoid injection of hyperbaric amethocaine produces an unexpectedly higher level of analgesia in adolescents than in adults.

Adolescent↗