Biomedical subjects

N Yasui

Publications and source records attributed to N Yasui.

At least 55 records · Page 3Linked to original sources

PubMed2000

Cerebral circulation and metabolism in the acute stage of subarachnoid hemorrhage.

OBJECT: The mechanism of reduction of cerebral circulation and metabolism in patients in the acute stage of aneurysmal subarachnoid hemorrhage (SAH) has not yet been fully clarified. The goal of this study was to elucidate this mechanism further. METHODS: The authors estimated cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), O2 extraction fraction (OEF), and cerebral blood volume (CBV) preoperatively in eight patients with aneurysmal SAH (one man and seven women, mean age 63.5 years) within 40 hours of onset by using positron emission tomography (PET). The patients' CBF, CMRO2, and CBF/CBV were significantly lower than those in normal control volunteers. However, OEF and CBV did not differ significantly from those in control volunteers. The significant decrease in CBF/CBV, which indicates reduced cerebral perfusion pressure, was believed to be caused by impaired cerebral circulation due to elevated intracranial pressure (ICP) after rupture of the aneurysm. In two of the eight patients, uncoupling between CBF and CMRO2 was shown, strongly suggesting the presence of cerebral ischemia. CONCLUSIONS: The initial reduction in CBF due to elevated ICP, followed by reduction in CMRO, at the time of aneurysm rupture may play a role in the disturbance of CBF and cerebral metabolism in the acute stage of aneurysmal SAH.

Acute Disease↗

PubMed1999

Enantioselective Single-Crystal-to-Single-Crystal Photodimerization of Coumarin and Thiocoumarin in Inclusion Complexes with Chiral Host Compounds.

An intermolecular enantioselective photoreaction by a single-crystal-to-single-crystal transformation has been carried out for the first time, as is evident from X-ray structure analysis and X-ray powder diffractometric studies. This reaction, the dimerization of the title compound to cyclobutane derivative 1 (X=O, S), provides a good example for studying the mechanism of topochemical reactions in the crystal.

Journal Article↗

PubMed1999

High prevalence of transfusion-transmitted virus among patients with non-B, non-C hepatocellular carcinoma.

BACKGROUND: Many patients with hepatocellular carcinoma are positive for hepatitis B surface antigen (HBsAg) or antibodies to hepatitis C virus (anti-HCV). Recently, transfusion-transmitted virus (TTV) DNA was identified in the serum of patients with non-B, non-C posttransfusion hepatitis. In this study, the prevalence of TTV DNA in the serum of patients with non-B, non-C hepatitis-associated hepatocellular carcinoma was evaluated. METHODS: Fifteen patients with hepatocellular carcinoma negative for HBsAg, antibodies to hepatitis B core antigen (anti-HBc), and anti-HCV antibodies were enrolled in this study (non-B, non-C group). Fifteen patients positive for HBsAg and negative for anti-HCV antibody (HBV group) and another group of patients negative for HBsAg but positive for anti-HCV antibody (HCV group) were also enrolled in this study. Data obtained from 27 healthy subjects negative for both HBsAg and anti-HCV antibody and normal levels of serum alanine aminotransferase represented controls. The healthy control group, the non-B, non-C group, and the HCV group were age-matched. TTV DNA was detected by heminested polymerase chain reaction in which specific primers were used. RESULTS: TTV DNA was detected in 10 of 15 patients (67%) in the non-B, non-C group. This prevalence rate in the non-B, non-C group was significantly higher than that in the HBV group (3 of 15 patients, 20%) and the control group (9 of 27 patients, 33%), but it was not significantly different from that in the HCV group (7 of 15 patients, 47%). The noncancerous hepatic tissue samples of 10 TTV-DNA positive patients in the non-B, non-C group included 2 with chronic hepatitis and 8 with cirrhosis. CONCLUSIONS: This study showed that TTV DNA is frequently detected in the serum of patients with non-B, non-C hepatocellular carcinoma. This result suggests a potential pathogenetic association between hepatocellular carcinoma and TTV infection.

Aged↗

PubMed1999

Microphthalmia-associated transcription factor interacts with PU.1 and c-Fos: determination of their subcellular localization.

Marked osteopetrosis is observed only in mi/mi mutant mice although normal osteoclastgenesis is observed in other mutant mice including null mutants at the mi locus. Mutant microphthalmia-associated transcription factor (mi-MITF) has defective nuclear localization potential. We found normal MITF (+-MITF)-c-Fos and mi-MITF-c-Fos complexes in the cytoplasm by immunoblotting, and showed that PU.1 bound with both +-MITF and mi-MITF using an electrophoretic mobility shift assay. Furthermore, the nuclear localization of PU.1 and c-Fos was inhibited by over-expressed mi-MITF in WEHI-3 cells. These results indicate that mi-MITF expressing in osteoclasts specifically binds to c-Fos and PU.1 which are essential transcription factors of osteoclastgenesis and that mi-MITF blocks the nuclear localization of these other transcription factors, which may result in osteopetrosis in mi/mi mutant mice.

Animals↗

PubMed1999

Maturational disturbance of chondrocytes in Cbfa1-deficient mice.

Cbfa1, a transcription factor that belongs to the runt-domain gene family, plays an essential role in osteogenesis. Cbfa1-deficient mice completely lacked both intramembranous and endochondral ossification, owing to the maturational arrest of osteoblasts, indicating that Cbfa1 has a fundamental role in osteoblast differentiation. However, Cbfa1 was also expressed in chondrocytes, and its expression was increased according to the maturation of chondrocytes. Terminal hypertrophic chondrocytes expressed Cbfa1 extensively. The significant expression of Cbfa1 in hypertrophic chondrocytes was first detected at embryonic day 13.5 (E13.5), and its expression in hypertrophic chondrocytes was most prominent at E14.5-16.5. In Cbfa1-deficient mice, whose entire skeleton was composed of cartilage, the chondrocyte differentiation was disturbed. Calcification of cartilage occurred in the restricted parts of skeletons, including tibia, fibula, radius, and ulna. Type X collagen, BMP6, and Indian hedgehog were expressed in their hypertrophic chondrocytes. However, osteopontin, bone sialoprotein, and collagenase 3 were not expressed at all, indicating that they are directly regulated by Cbfa1 in the terminal hypertrophic chondrocytes. Chondrocyte differentiation was severely disturbed in the rest of the skeleton. The expression of PTH/PTHrP receptor, Indian hedgehog, type X collagen, and BMP6 was not detected in humerus and femur, indicating that chondrocyte differentiation was blocked before prehypertrophic chondrocytes. These findings demonstrate that Cbfa1 is an important factor for chondrocyte differentiation.

Animals↗

PubMed1999

Effects of itraconazole on the steady-state plasma concentrations of bromperidol and reduced bromperidol in schizophrenic patients.

RATIONALE: A previously reported pharmacokinetic interaction between bromperidol and carbamazepine, an inducer of cytochrome P450 (CYP) 3A4, suggests possible involvement of CYP3A4 in the metabolism of bromperidol. OBJECTIVE: We investigated pharmacokinetic interaction between bromperidol and itraconazole, a potent inhibitor of CYP3A4, to clarify the involvement of CYP3A4 in the metabolism of bromperidol and its reduced metabolite. METHODS: Itraconazole 200 mg/day for 7 days was coadministered to eight schizophrenic patients treated with a fixed dose of bromperidol 12 or 24 mg/day for at least 2 weeks. Blood samples were taken before and 1 week after itraconazole coadministration and 1 week after its discontinuation, together with clinical assessments using the Brief Psychiatric Rating Scale (BPRS) and the Udvalg for Kliniske Undersøgelser (UKU) Side Effect Rating Scale. RESULTS: Plasma concentrations of bromperidol during itraconazole coadministration (16.7+/-4.9 ng/ml) were significantly higher (P<0.01) than before itraconazole coadministration (8.9+/-4.4 ng/ml) and 1 week after its discontinuation (9.9+/-4.3 ng/ml). Plasma concentrations of reduced bromperidol during itraconazole coadministration (3.6+/-2.9 ng/ml) were significantly higher (P<0.01) than before itraconazole coadministration (1.8+/-1.3 ng/ml). No changes were observed in BPRS and UKU scores throughout the study. CONCLUSIONS: The pharmacokinetic interaction between bromperidol and itraconazole is probably due to the inhibitory effect of itraconazole on the metabolism of bromperidol. This study provides in vivo evidence of involvement of CYP3A4 in the metabolism of bromperidol and reduced bromperidol.

Adult↗

PubMed1999

Cerebral blood-flow responses to induced hypotension and to CO2 inhalation in patients with major cerebral artery occlusive disease: a positron-emission tomography study.

Our aim was to study the relationship between cerebral blood flow (CBF) responses to induced hypotension and to CO2 inhalation in patients with occlusive disease of the carotid or middle cerebral arteries. In 13 patients (8 men, 5 women) aged 31-73 years (mean +/- 1 SD = 63.2 +/- 10.6), regional CBF values during the resting state (CBFrest), 7% CO2 inhalation (CBFhypercapnia), and hypotension induced by 10-20 microg/kg/min intravenous trimethaphan (CBFhypotension) were measured using positron-emission tomography (PET) with H2(15)O. The % CBF change during induced hypotension (% CBFhypotension) was defined as (CBFhypotension - CBFrest)/CBFrest multiplied by 100. The % CBF change during CO2 inhalation (% CBFhypercapnia) was defined as (CBFhypercapnia - CBFrest)/CBFrest/mm Hg arterial partial pressure of CO2 x 100. We defined symptomatic hemispheres as those with a stenotic or occlusive lesion with neurological symptoms or signs and asymptomatic hemispheres as those which had a similar lesion and/or were influenced by the collateral flow pattern without neurological symptoms. In the territory of the occlusive lesion, % CBFhypotension correlated significantly with % CBFhypercapnia (r = 0.793, P < 0.002) in the symptomatic hemispheres. In the brain regions in which trimethaphan did not induce a reduction in CBF. % CBFhypercapnia was 6.13 +/- 1.79. In those in which % CBFhypotension ranged from 0 to -5, from -5 to -10, and more than -10%, % CBFhypercapnia was 4.05 +/- 1.99, 3.21 +/- 1.17, and 1.73 +/- 1.61, respectively, with significant differences between each pair of groups. In the asymptomatic hemispheres, % CBFhypotension also correlated with % CBFhypercapnia (r = 0.979, P < 0.0001). Failure to maintain CBF during induced hypotension was associated with diminished cerebrovascular vasoreactivity to hypercapnia in patients with arterial disease. This may indicate that failure of autoregulation can be assessed by the CBF response to both induced hypotension and CO2 inhalation. From the technical point of view, estimation of the CO2 response may be useful for assessing failure of autoregulation.

Administration, Inhalation↗

PubMed1999

Effects of the CYP2D6*10 allele on the steady-state plasma concentrations of haloperidol and reduced haloperidol in Japanese patients with schizophrenia.

BACKGROUND: The CYP2D6*10 (*10) allele that causes decreased CYP2D6 activity is present in Asians with a high frequency of about 50%. In this study we studied the effects of the *10 allele on the steady-state plasma concentrations (Css) of haloperidol and reduced haloperidol. METHODS: The subjects were 67 Japanese inpatients with schizophrenia who had only the wild-type or *10 alleles. Thirty-four patients were homozygous for the wild-type allele, and 26 were heterozygous and 7 were homozygous for the *10 allele. All patients had been receiving 12 mg/day haloperidol for at least 2 weeks. Plasma concentrations of haloperidol and reduced haloperidol were measured by HPLC. RESULTS: The mean +/- SD values of haloperidol Css in the patients with 0, 1, and 2 *10 alleles were 22.8+/-11.0, 30.1+/-10.6, and 31.2+/-21.2 nmol/L, respectively, and those values for reduced haloperidol were 6.1+/-2.9, 9.5+/-3.7, and 9.9+/-6.2 nmol/L, respectively. The mean haloperidol Css was significantly (P < .05) higher in the patients with 1 *10 allele than in those with no *10 alleles. The mean Css of reduced haloperidol was significantly (P < .05) higher in the patients with 1 and 2 *10 alleles than in those with no *10 alleles. CONCLUSION: This study suggests that the *10 allele plays an important role in controlling the Css of both haloperidol and reduced haloperidol, especially in Asian subjects.

Adult↗

PubMed1999

Ruptured anterior spinal artery aneurysm: a case report.

BACKGROUND: Spinal artery aneurysms are rare, and are usually found in association with arteriovenous malformations or coarctation of the aorta. CASE REPORT: A 42-year-old man with a ruptured anterior spinal artery aneurysm is presented here. He experienced subarachnoid hemorrhage, which was confirmed by computed tomography. Magnetic resonance imaging revealed an aneurysm in front of the upper part of the medulla. Angiography demonstrated bilateral vertebral artery occlusion. Distal vertebral arteries and the basilar artery were perfused via the dilated anterior spinal artery, which originates in the right subclavian artery. The aneurysm was located at the distal part of the anterior spinal artery, and was successfully clipped through a lateral suboccipital craniotomy 2 months after bleeding from the aneurysm. After rehabilitation, the patient was able to walk with no apparent neurologic deficit. CONCLUSIONS: This case suggests that the anterior spinal artery as a collateral route after bilateral vertebral artery occlusion is under hemodynamic stress, resulting in aneurysm formation and rupture.

Adult↗

PubMed1999

Determination of risperidone and 9-hydroxyrisperidone in human plasma by high-performance liquid chromatography: application to therapeutic drug monitoring in Japanese patients with schizophrenia.

A high-performance liquid chromatographic method has been developed for the simultaneous determination of risperidone and its major active metabolite 9-hydroxyrisperidone in plasma. Risperidone and 9-hydroxyrisperidone in plasma were extracted using a CN bonded-solid phase cartridge, followed by, C4 reversed-phase HPLC separation. Risperidone, 9-hydroxyrisperidone and trazodone as an internal standard were detected by ultraviolet absorbance at 280 nm. It was possible to determine risperidone in the concentration range of 1.0-100.0 ng/ml(-1) and 9-hydroxyrisperidone at a range of 2.0-200.0 ng/ml(-1). The detection limits of risperidone and 9-hydroxyrisperidone were 0.5 and 1.0 ng/ml(-1), respectively. The mean recoveries of risperidone and 9-hydroxyrisperidone added to plasma were less than 92.0 and 92.6%, with a coefficient of variation of less than 10.6 and 10.5%, respectively. This method has been used for the simultaneous determination of steady-state plasma concentration (Css) of risperidone and 9-hydroxyrisperidone in schizophrenic patients treated with 3-, 6-, and 12-mg risperidone oral doses per day.

Adult↗

PubMed1999

Characteristics and risk factors of acute dystonia in schizophrenic patients treated with nemonapride, a selective dopamine antagonist.

The occurrence of acute dystonia was prospectively monitored in 39 schizophrenic patients (18 male and 21 female) treated with 9 to 27 mg/day of nemonapride, a selective dopamine antagonist, and the relationship of acute dystonia with characteristics of patients and plasma concentrations of the drug and prolactin was investigated. Twenty (51.3%) of 39 patients had dystonic reactions, the onsets of which occurred within 3 days after the initiation of treatment in 90% of dystonic patients. The incidence of acute dystonia was significantly higher in male than in female patients (77.8% vs. 28.6%, p < 0.05). Younger male patients (< or = 30 years) especially had an extremely high incidence of this side effect (91.7%). A positive correlation between prolactin response after 1 week of treatment and dystonia rating scores was found in male (Spearman rank correlation: r(s) = 0.606,p < 0.01) but not in female patients (r(s) = -0.378,p = not significant). These results suggest that young male patients have the highest risk of neuroleptic-induced dystonia. Prolactin response after 1 week of treatment as an index of dopamine blockade may reflect vulnerability to the development of acute dystonia at least in male patients treated with nemonapride.

Acute Disease↗

PubMed1999

Effects of itraconazole on the steady-state plasma concentrations of haloperidol and its reduced metabolite in schizophrenic patients: in vivo evidence of the involvement of CYP3A4 for haloperidol metabolism.

The effects of itraconazole, a potent inhibitor of cytochrome P450 (CYP) 3A4, on the steady-state plasma concentrations of haloperidol and reduced haloperidol were examined in schizophrenic patients. Thirteen schizophrenic patients treated with haloperidol 12 or 24 mg/day received 200 mg/day of itraconazole for 7 days. Plasma concentrations of haloperidol and reduced haloperidol were measured by high-performance liquid chromatography together with clinical assessment by the Brief Psychiatric Rating Scale (BPRS) and the Udvalg for Kliniske Undersogelser side effect rating scale just before and during itraconazole treatment and 1 week after its discontinuation. Plasma concentrations of haloperidol and reduced haloperidol during the itraconazole treatment (16.9 +/- 11.2 and 6.1 +/- 6.6 ng/mL, respectively) were significantly (p < 0.01) higher than those observed before itraconazole treatment (13.0 +/- 7.9 and 4.9 +/- 5.1 ng/mL) or 1 week after its discontinuation (13.5 +/- 8.2 and 4.9 +/- 5.0 ng/mL). No change was found in clinical symptoms assessed by BPRS, whereas neurologic side effects were significantly (p < 0.05) increased during itraconazole coadministration. The elevated plasma concentrations of haloperidol and reduced haloperidol during itraconazole coadministration were likely due to the inhibitory effects of itraconazole on the metabolism of haloperidol and reduced haloperidol. Thus, this study may provide in vivo evidence of involvement of CYP3A4 in the metabolism of haloperidol and possibly in that of reduced haloperidol. Deterioration of neurologic side effects during itraconazole treatment may result from the increased plasma concentrations of haloperidol and reduced haloperidol during itraconazole treatment.

Adult↗

PubMed1999

Lack of significant pharmacokinetic interaction between haloperidol and grapefruit juice.

The effects of repeated ingestion of grapefruit juice, an inhibitor of cytochrome P4503A4 (CYP3A4), on the steady-state plasma concentrations of haloperidol and reduced haloperidol were examined. Twelve schizophrenic inpatients receiving haloperidol 12 mg/day, ingested grapefruit juice 600 ml/day for 7 days. Blood samples were collected before and during grapefruit juice coadministration and 1 week after its discontinuation together with an assessment of clinical status. Plasma drug concentrations were measured using high-performance liquid chromatography. Clinical status for each patient was assessed by the Brief Psychiatric Rating Scale (BPRS) and the UKU side-effect rating scale (UKU). Plasma concentrations of haloperidol and reduced haloperidol during grapefruit juice coadministration (9.0 +/- 3.0 and 2.6 +/- 1.4 ng/ml, respectively) were not significantly different from those before grapefruit juice coadministration (9.1 +/- 2.8 and 2.6 +/- 1.5 ng/ml) or those 1 week after its discontinuation (8.8 +/- 2.7 and 2.6 +/- 1.3 ng/ml). There was no change in the scores of BPRS or UKU during the study period. The present results shows that grapefruit juice does not affect the plasma concentrations of haloperidol and reduced haloperidol or clinical status in patients receiving haloperidol.

Adult↗

PubMed1999

Effects of carbamazepine coadministration on plasma concentrations of the enantiomers of mianserin and of its metabolites.

Concentrations of the enantiomers of unconjugated and of total (unconjugated plus conjugated) mianserin, desmethylmianserin and 8-hydroxymianserin were measured in 12 patients before and after the introduction of carbamazepine. The dose of mianserin was 60 mg/d, carbamazepine was coadministered at 400 mg/d for 4 weeks, and blood samples were taken at weekly intervals after the introduction of carbamazepine. Each week, carbamazepine significantly decreased plasma concentrations of unconjugated and total (S)-mianserin (the more potent enantiomer) and of unconjugated and total (R)-mianserin. On average, plasma concentrations of unconjugated and total (S)-mianserin and of unconjugated and total (R)-mianserin were 55%, 56%, 66%, and 55%, respectively, of the corresponding values before introduction of carbamazepine. These results strongly suggest the involvement of CYP3A4, the major CYP enzyme induced by carbamazepine, in the metabolism of both enantiomers of mianserin. A strong decrease in the concentrations of (S)-8-hydroxymianserin was also measured (on average, the concentrations were 69% of the corresponding values before carbamazepine introduction). Conversely, plasma concentrations of unconjugated and of total (S)-desmethylmianserin, (R)-desmethylmianserin, and (R)-8-hydroxymianserin were only slightly modified by carbamazepine. From a clinical point of view, as a therapeutic window for (S)-mianserin has been recently suggested, the dose of racemic mianserin for a patient whose (S)-mianserin concentrations have been stabilized within this therapeutic window would need to be approximately doubled if carbamazepine, at 400 mg/d, is introduced as a comedication.

Adult↗

PubMed1999

No pharmacokinetic but pharmacodynamic interactions between cisapride and bromperidol or haloperidol.

Pharmacokinetic and pharmacodynamic interactions between the gastrokinetic drug cisapride and the antipsychotic drugs bromperidol and haloperidol were studied in 29 schizophrenic inpatients. Fourteen patients were taking bromperidol (12-24 mg/d), and 15 were taking haloperidol (12-36 mg/d). Cisapride 10 mg/d was coadministered for 1 week, and blood sampling was performed before cisapride treatment, 1 week after starting cisapride treatment, and I week after stopping cisapride treatment. On the same days as the blood sampling, psychotic symptoms and side effects were evaluated using the Brief Psychiatric Rating Scale (BPRS) and the Udvalg for Kliniske Undersøgelser (UKU) side effect rating scale (UKU), respectively. Plasma concentrations of bromperidol, haloperidol, and their reduced metabolites were measured by high-performance liquid chromatography. The mean BPRS scores after adding cisapride were significantly higher than those before cisapride (p<0.01) and after stopping cisapride (p<0.001) in the haloperidol group in this uncontrolled study. A similar tendency was observed in the bromperidol group, although it did not reach statistical significance (p = 0.08). Cisapride coadministration caused no significant changes in the mean plasma concentrations of bromperidol, haloperidol, and their reduced metabolites or in the mean UKU score. The present study suggests that there is no significant pharmacokinetic interaction between cisapride and bromperidol or haloperidol, but cisapride appears to deteriorate psychotic symptoms by a pharmacodynamic interaction in schizophrenic patients treated with haloperidol.

Antipsychotic Agents↗

PubMed1999

Mechanical tension-stress induces expression of bone morphogenetic protein (BMP)-2 and BMP-4, but not BMP-6, BMP-7, and GDF-5 mRNA, during distraction osteogenesis.

Bone lengthening with osteotomy and gradual distraction was achieved in 57 rats, and the effect of mechanical tension-stress on gene expression of bone morphogenetic proteins (BMPs) was investigated by in situ hybridization and Northern blot analysis using probes of BMP-2, BMP-4, BMP-6, BMP-7, and growth/differentiation factor (GDF)-5. There was a lag phase for 7 days after femoral osteotomy until gradual distraction was carried out for 21 days at a rate of 0. 25 mm/12 h using a small external fixator. The signals of the above BMPs mRNA were not detected in the intact rat bone but they were induced after osteotomy except those for BMP-7. By 4 days after osteotomy, BMP-2 and BMP-4 mRNAs were detected in chondrogenic precursor cells in the subperiosteal immature callus. BMP-6 and GDF-5 mRNA were detected in more differentiated cells in chondroid bone. By 7 days after osteotomy, cartilaginous external callus and bony endosteal callus were formed. Meanwhile, the signals of BMP-2 and BMP-4 mRNAs declined to preoperative levels, whereas the signals of BMP-6 and GDF-5 mRNAs were rather elevated. As distraction was started, the callus elongated and eventually separated into proximal and distal segments forming a fibrous interzone in the middle. Expression of BMP-2 and BMP-4 mRNAs was markedly induced at this stage. Their signals were detected widely among chondrogenic and osteogenic cells and their precursor cells sustaining mechanical tension-stress at the fibrous interzone. BMP-6 and GDF-5 mRNAs were detected exclusively in chondrogenic cells at both ends of the fibrous interzone, where endochondral ossification occurred. But neither mRNA was detected in terminally differentiated hypertrophic chondrocytes. As distraction advanced, the cartilage was progressively resorbed from both ends and new bone was formed directly by intramembranous ossification. There was no new cartilage formation in the advanced stage of distraction. The signals of BMP-6 and GDF-5 mRNA declined by this stage, while those of BMP-2 and BMP-4 were maintained at high level for as long as distraction was continued. After completion of distraction, the fibrous interzone fused and the lengthened segment was consolidated. BMP-2, BMP-4, BMP-6, nor GDF-5 was expressed at this stage. The signals of BMP-7 were not detected throughout the experiment. The present results suggest that excellent and uninterrupted bone formation during distraction osteogenesis owes to enhanced expression of BMP-2 and BMP-4 genes by mechanical tension-stress. Abundant gene products of BMP-2 and BMP-4 could induce in situ bone formation by paracrine and autocrine mechanisms.

Animals↗

PubMed1999

Histological changes in the rat common carotid artery induced by aneurysmal wrapping and coating materials.

Histological changes in and around the arterial walls of rats were investigated following topical application of aneurysmal wrapping and coating materials, including a fibrin glue, a cyanoacrylate glue (Biobond), and cotton fibers (Bemsheet). Bilateral common carotid arteries were exposed using sterile techniques, and one of the test materials was applied to the right artery. The left artery was used as the control. Changes in arterial histology were evaluated at 2 weeks, 1 month, 2 months, and 3 months after surgery. The fibrin glue was surrounded by intense inflammation at 2 weeks after surgery. Both the fibrin glue and inflammation had disappeared at 2 months, but the glue had induced mild inflammation in the adventitia. Biobond caused chronic inflammation, necrosis of the media, and thickening of the arterial wall due to fibrosis in both the media and adventitia. Bemsheet produced chronic inflammation, progressive fibrosis, and granuloma. Connective tissue increased in the adventitia, but no major changes were observed in the media. The Bemsheet fibers remained unchanged, and adhered to the arterial wall. Although arterial stenoses were not observed in the present study, the results suggest that cyanoacrylate glue can cause the arterial occlusive lesions observed following aneurysm surgery.

Animals↗

PubMed1999

Hypothermia bed system for stroke patients. Technical note.

A new hypothermia bed system was used to induce mild hypothermia (33-35 degrees C) in six patients with stroke due to subarachnoid hemorrhage, hypertensive intracerebral hemorrhage, or embolic internal carotid artery occlusion. The system bed contained all necessary equipment including a respirator, a cooling unit, physiological monitors, and a storage battery. Surface cooling of the patients was performed using water-circulating blankets, and core temperature was maintained based on bladder temperature and a feedback computer program. During hypothermic therapy, patient transfer and radiological examination including computed tomography and positron emission tomography could be easily and safely performed. Differences between the measured bladder temperature and the target temperature were approximately +/- 0.1 degree C. The proposed hypothermia system bed may be useful for serial radiological examination of patients with stroke.

Adult↗