Effect of Miscanthus sinensis var. purpurascens Flower Extract on Proliferation and Molecular Regulation in Human Dermal Papilla Cells and Stressed C57BL/6 Mice / 中国结合医学杂志

<p><b>OBJECTIVES</b>To investigate the hair growth-promoting effect of Miscanthus sinensis var. purpurascens (MSP) flower extracton on in vitro and in vivo models.</p><p><b>METHODS</b>MSP flower extract was extracted in 99.9% methanol and applied to examine the proliferation of human dermal papilla cells (hDPCs) in vitro at the dose of 3.92-62.50 μg/mL and hair growth of C57BL/6 mice in vivo at the dose of 1000 μg/mL. The expression of transforming growth factor β1 (TGF-β1), hepatocyte growth factor (HGF), β-catenin, substance P was measured by relative quantitative realtime polymerase chain reaction. Histopathological and immunohistochemical analysis were performed.</p><p><b>RESULTS</b>MSP (7.81 μg/mL) down-regulated TGF-β1 and up-regulated HGF and β-catenin in hDPCs (P<0.01). MSP (1000 μg/mL)-treated mice showed the earlier transition of hair follicles from the telogen to the anagen phase. The number of mast cells was lower in the MSP-treated mice than in other groups (P<0.05 vs. NCS group). Substance P and TGF-β1 were expressed in hair follicles and skin of the MSP group lower than that in negative control. Stem cell factor in hair follicles was up-regulated in the MSP-treated mice (P<0.01).</p><p><b>CONCLUSIONS</b>The MSP flower extract may have hair growth-promotion activities.</p>

Varicella Zoster Meningitis in an Immunocompetent Child / 대한소아신경학회지

Neurologic complications associated with varicella zoster virus (VZV) are rare in children. A 13-year-old boy was hospitalized due to headache, fever, and vomiting. Aseptic viral meningitis was strongly suspicious based on findings on physical exam, cerebrospinal fluid examination, and brain magnetic resonance imaging. On the second day of hospitalization, typical zosteriform rashes developed on his left chest wall across the T7-T8 dermatome. Tzanck test of the skin lesion was positive and polymerase chain reaction test for VZV was positive on the second cerebrospinal fluid examination. Serum immunoglobulin levels were within normal range. Intravenous acyclovir was started and symptoms and signs of meningitis gradually improved and the patient was discharged without any complications. In immunocompetent children, VZV meningitis is rare and requires rapid diagnosis and treatment. Therefore, it is necessary to prompt diagnosis and treatment thorough medical history, physical examination and laboratory examination.

Clinical Features of Herpes Zoster in Children according to Immune Status / 대한소아신경학회지

PURPOSE: Herpes zoster appears in all ages and its incidence progressively increase. It is more common in elderly people or immunocompromised people and can be accompanied by serious complications. This study was performed to investigate the clinical manifestation of herpes zoster according to immune status in children. METHODS: This study was retrospectively included 307 children under 18 years who were diagnosed and treated with herpes zoster at Inha University Hospital from 1997 to 2017 based on medical records. These patients were divided into two groups according to their immunity and their clinical features were compared. RESULTS: The mean age of the total 307 patients was 10.2 years, 151 (49.2%) in males. Eighty-seven patients were hospitalized and 220 patients were treated in an outpatient clinic. Most patients received antiviral treatment. The most common dermatomal distribution of the skin lesion was the thoracic region, followed by trigeminal, lumbar and sacral, cervical region. Twenty-one patients were immunocompromised and fifteen of them were hematologic disorders. Admission rate, history of chickenpox and mean duration of treatment were significantly higher in immunocompromised group (P < 0.05). There was no significant difference in age, dermatomal distribution and complication between the two groups. Complications were observed in 50 cases and more than half of them were zoster ophthalmicus. Another complication was Ramsay-Hunt syndrome, meningitis and skin infection. CONCLUSION: Immunocompromised patients had a longer duration of treatment and a higher history of chickenpox. The incidence of complications, dermatomal distribution and age did not differ from that of immunocompetent children.

Postoperative Monitoring Following Jaw Surgery Is Essential

No abstract available.

Abnormal Integrity of Corticocortical Tracts in Mild Cognitive Impairment: A Diffusion Tensor Imaging Study

Mild cognitive impairment (MCI) has been defined as a transitional state between normal aging and Alzheimer disease. Diffusion tensor imaging (DTI) can estimate the microstructural integrity of white matter tracts in MCI. We evaluated the microstructural changes in the white matter of MCI patients with DTI. We recruited 11 patients with MCI who met the working criteria of MCI and 11 elderly normal controls. The mean diffusivity (MD) and fractional anisotropy (FA) were measured in 26 regions of the brain with the regions of interest (ROIs) method. In the MCI patients, FA values were significantly decreased in the hippocampus, the posterior limb of the internal capsule, the splenium of corpus callosum, and in the superior and inferior longitudinal fasciculus compared to the control group. MD values were significantly increased in the hippocampus, the anterior and posterior limbs of the internal capsules, the splenium of the corpus callosum, the right frontal lobe, and in the superior and the inferior longitudinal fasciculus. Microstructural changes of several corticocortical tracts associated with cognition were identified in patients with MCI. FA and MD values of DTI may be used as novel biomarkers for the evaluation of neurodegenerative disorders.

Wernicke's Encephalopathy following Gastrectomy in Patients with Gastric Cancer

Wernicke's encephalopathy is a neurological disorder that is caused by a thiamine deficiency, and characterized by acute confusion, ataxia, a change in the patient's state of mind and abnormal eye movement (op-thalmophlegia and nystag-mus). This encephalopathy can be found in patients with chronic alcoholism, anorexia nervosa, hemodialysis, AIDS and gastroplasty for morbid obesity. The diagnosis of this disease is difficult because not all cases display the typical symptoms. However, this disease can be confirmed not only by the clinical symptoms but also by the brain MRI findings, low thiamine level and clinical response to thiamine replacement therapy. We experienced two cases of Wer-nicke's encephalopathy in patients who underwent a gas-trec-tomy for gastric cancer. However, this condition was not diagnosed until the patients showed neurological symptoms and the typical MRI findings. These patients improved after vitamin B(1) (thiamine) replacement.

The Effect of 1, 25-Dihydroxyvitamin D3 on Dopaminergic Neurons and Microglial Activation in Parkinsonian Rat Model Induced by 6-Hydroxydopamine

BACKGROUND: Recent studies have shown increasing evidence for microglial activation in neuronal degeneration in Parkinson's disease (PD), although the cause of PD remains unclear. Recent studies have also shown that 1alpha, 25-dihydroxyvitamin D3 (vitamin D3) exert neuroprotective effects by inducing an increased expression of neurotrophic factors, suggesting the possibility of vitamin D3 for the treatment of PD and other neurodegenerative diseases. The purpose of this study was to investigate the effect of vitamin D3 on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity and microglial activation in adult rats. METHODS: Adult male Sprague-Dawley rats were subcutaneously injected with vitamin D3 or 0.1% ethanol for seven consecutive days and then infused unilaterally with 6-OHDA in the medial forebrain bundle. After 7 days of injection with 6-OHDA, the substantia nigra was examined by immunohistochemistry. RESULTS: The number of tyrosine hydroxylase (TH)-positive neurons in the lesioned substantia nigra pars compacta of vitamin D3 and ethanol groups was 84.8 +/- 18.84 and 52.6 +/- 13.23, respectively, fewer than that of the contralateral side (122.35 +/- 9.79 and 123.81 +/- 12.11, respectively) (P<0.05). The vitamin D3 group showed significantly higher numbers of the TH-positive neurons than that of the ethanol group (P<0.05). CD11b-positive microglial immunoreactivity was stronger in the lesion side than that of the normal side, and it was much weaker in the vitamin D3 group than that of the ethanol group (P<0.05). CONCLUSIONS: These results indicate that vitamin D3 protects dopaminergic neurons from the neuronal injury induced by 6-OHDA, possibly by the mechanism involving microglial activation.

Association of Vitamin D Receptor Gene Polymorphism and Parkinson's Disease in Koreans

1alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3), which is the biologically active form of vitamin D, has anti-inflammatory effects and can prevent experimental Parkinson's disease (PD). 1,25(OH)2D3 exerts most of its actions only after it binds to its specific nuclear receptors. Eighty-five Korean patients with PD and 231 unrelated healthy individuals were evaluated to determine if vitamin D receptor gene (VDRG) BsmI polymorphisms were markers for the susceptibility to PD in Korean patients. Each polymorphism was detected using polymerase chain reaction (PCR)-based restriction analysis. In addition, the relationship between the BsmI polymorphisms and the clinical manifestations of PD was evaluated. Overexpression of the b allele (91.2 vs. 85.7%; p=0.069) and homozygote bb (84.7 vs. 72.7%; p=0.043) was found in the PD patients compared with the controls. These results show for the first time an association between PD and a VDRG polymorphism, which might be involved in the pathogenesis of PD, or in the linkage disequilibrium of the VDRG to another pathogenic gene locus.

Medical Treatment of Cerebral Infarction / 대한뇌혈관외과학회지

Anticoagulants and antiplatelet agents have been widely used and studied in both the management of acute stroke and for stroke prevention. The use of anticoagulants and antiplatelet agents in acute ischemic stroke is aimed at preventing stroke recurrence and reducing stroke progression. Studies examining unfractionated heparin following acute ischemic stroke failed to show an overall benefit. Reductions in thromboembolic events and progression of stroke were offset by an increased risk of major bleeding including intracerebral hemorrhage. Low molecular weight heparin compounds and hepanoids in acute ischemic stroke similarly have failed to prove overall benefit when bleeding complications, especially intracerebral hemorrhage, are considered along with reductions in thromboembolic complications. Ancrod, an agent capable of reducing circulating fibrinogen levels has been shown in clinical trials to improve outcome following stroke when administered within three ours of stroke onset. Antiplatelet agents have been evaluated in acute ischemic stroke. The largest studies have examined the role of aspirin therapy (IST, CAST). Studies have shown a small but statistically significant improvement in the aspirin-treated patients treated within 48 hours. Abciximab, a IIB/IIIA inhibitor, has been studied in acute ischemic stroke with an acceptable safety profile and encouraging findings of potential benefit. These studies have led to an ongoing trial of Abciximab (ReoPro) in acute ischemic stroke. Other ongoing clinical trials in acute ischemic stroke include studies of clopidogrel following TIA and unfractionated heparin in acute ischemic stroke. Antithrombotic agents are widely used for stroke prevention. Long-term oral anticoagulation has been proven of benefit in the prevention of stroke in high risk patients with atrial fibrillation. Two large clinical trials in high risk patients with atrial fibrillation have examined a direct thrombin inhibitor, Ximelagatran, compared to warfarin for stroke prevention. These studies have shown similar thromboembolic events with Ximelagatran comparable to warfarin. The risks of bleeding were reduced with Ximelagatran as compared to warfarin treatment. Ximelagatran does not require regular monitoring of coagulation or dose adjustments. There is an increased risk of liver enzyme abnormalities in some patient receiving Ximelagatran. Antiplatelet agents are the mainstay of antithrombotic therapy for secondary stroke prevention with four agents currently approved for use (aspirin, ticlopidine, clopidogrel, and extended release dipyridamole plus aspirin). A number of studies are underway examining the role of antiplatelet agents in combination or for additional indications. These studies include MATCH, CHARISMA, SPS3, ARCH, CARESS, PROFESS, and WASID.

Protective Effects of the Green Tea Polyphenol(-)-epigallocatechin Gallate Against Ischemia Reperfusion Injury Induced by Middle Cerebral Artery Occlusion in Rats

BACKGROUND: EGCG(epigallocatechin gallate), a major green tea extract, is a potent free radical scavenger which has been shown to reduce free radical-induced lipid peroxidation. The purpose of this study was to examine whether EGCG reduces focal ischemia/reperfusion-induced brain injury in rats. METHODS: Male Wistar rats were anesthetized with ketamine and xylazine and subjected to 120 min of temporary middle cerebral artery occlusion by an intraluminal nylon suture coated with poly-L-lysine. The drug (EGCG, n=8) or vehicle (normal saline, n=8) was administered iv.(as a 50 mg/kg bolus) immediately after the onset of middle cerebral artery occlusion. Neurologic status was evaluated 2 hours after occlusion and 24 hours after. Twenty-four hours after ischemia, the brain was perfusion-fixated and the infarct volume was determined. RESULTS: EGCG significantly improved the neurological status at 24 hours after middle cerebral artery occlusion.(p<0.05), and reduced total infarct volumes (p<0.01). CONCLUSIONS: These results demonstrate the neuroprotective effect of EGCG in a rat model of transient focal cerebral ischemia.

Predictive Value of C-Reactive Protein in the Differential Diagnosis of Acute Meningitis in Adults

BACKGROUND: The aim of this study was to clarify to what extent bacterial meningitis could be distinguished from aseptic or tuberculous meningitis through C-reactive protein (CRP) in adults. METHODS: We retrospectively analyzed the medical records of 91 patients aged 15~81 years who had been hospitalized for acute meningitis and underwent lumbar puncture due to suspected central nervous system infection. RESULTS: We included 50 patients with aseptic meningitis, 23 patients with acute bacterial meningitis, and 18 patients with tuberculous meningitis. Blood CRP was higher in bacterial meningitis. None of the patients with bacterial meningitis had a CRP value of under 20 mg/dl. The CRP values were under 20 mg/dl in 92% of the patients with aseptic meningitis and in 73% of those with tuberculous meningitis. Taking a CRP level of above 20 mg/dl as a positive discriminatory factor for bacterial meningitis, the sensitivity and specificity were 1.0, 0.88. To better predict whether a patient has bacterial or nonbacterial meningitis, we developed a canonical discriminant function equation using CRP and CSF parameter, and finally concluded that blood CRP was a good predictive indicator that differentiated bacterial meningitis from aseptic or tuberculous meningitis at admission. CONCLUSIONS: The CRP measurement, is easily performed and inexpensive. We believe it is worth analyzing CRP whenever meningitis is suspected, it can also limit the unnecessary use of antibiotics.

Correlation between Multifocal Hypointense Cerebral Lesions on Gradient-echo MRI and White Matter Changes in Patients with Stroke

BACKGROUND: The multifocal hypointense cerebral lesions (MHCLs) on gradient echo (GE)-MRI and white matter changes on T2WI have been thought to be indicative of microangiopathy. The purpose of this study is to elucidate the relationship between MHCLs and white matter (WM) changes and the clinical significance of WM changes in stroke patients. METHODS: We retrospectively reviewed MRI and clinical data of 115 patients with stroke (56 female and 59 male). Periventricular and deep white matter hyperintensity (PVHI and DWMHI) were measured by semiquantative rating scale proposed by Mantyla. The round, hypointense signal, less than 7 mm in diameter on GE-MRI were counted as MHCLs. The association between risk factors of stroke and MHCLs on GE-MRI and sum of the white matter change scores and total number of MHCLs were analyzed, respectively. RESULTS: MHCLs on GE-MRI were significantly associated with old age (p<0.05) and hypertension (p<0.001) among risk factors of stroke. The distribution of MHCLs in subcortical area is associated with hypertension (p<0.05) and total number of MHCLs was significantly associated with sum of the white matter change scores (p<0.05). CONCLUSIONS: MHCLs on GE-MRI were significantly associated with severity of WM changes. Severe WM change may be an indicator of advanced small artery disease of the brain with an increased risk factor for bleeding. This should be taken into consideration when treating patients with stroke.

The Different Patterns of Behavioral Derangements in Subcortical Vascular Dementia and Alzheimer's Disease: Evaluated by the Korean Version of the Neuropsychiatric Inventory

BACKGROUND: The neuropsychiatric derangements in dementing patients are common and troublesome in their managements. The purpose of this study is to compare the behavioral changes in patients with subcortical vascular dementia (SVaD) and to those in patients with Alzheimer's disease (AD) by using the Korean version of the neuropsychiatric inventory (K-NPI). METHODS: The K-NPI was administrated to the close caregivers of 19 patients with AD (who met the criteria of the NINCDS-ADRDA for probable AD) and 14 patients with SvaD (who met the criteria of the NINDS-AIREN criteria for probable or possible VaD). Groups were matched for age, education and dementia severity. We evaluated the prevalence, the composite score (frequency X severity) of each behavioral domain in K-NPI between two groups. RESULTS: The most common behavioral disturbances were anxiety (63%) in AD and apathy/indifference (93%) in SVaD. Patients with SVaD had significantly greater total K-NPI scores than patients with AD and exhibited apathy/indifference, agitation/aggression and anxiety more frequently. Composite score of apathy/indifference over 4.7 point discriminates between AD and SVaD with accuracy of 75.8%. CONCLUSIONS: The K-NPI provides behavioral profiles that differentiate patients with SVaD from patients with AD. Patients with SVaD are more behaviorally disturbed. Clinicians need to pay more attention to the behavioral disturbances when managing the patients with SVaD.

The Selective Cyclooxygenase-2 Inhibitor Rofecoxib Reduces Chronic Cerebral Hypoperfusion-induced Apoptosis in the Rat Hippocampus

BACKGROUND: Chronic cerebral hypoperfusion induced by permanent occlusion of bilateral common carotid arteries (2VO) in rats caused cognitive deficits and neuronal damage. Cyclooxygenase-2 (COX-2) inhibitor was reported to attenuate both post-ischemic prostaglandin accumulation and neuronal damage. We studied the expression of mRNA of COX-2 in the hippocampus during hypoperfusion and the effectiveness of selective cyclooxygenase-2 inhibitor, rofecoxib, in preventing the neuronal damage of this model. METHODS: Bilateral common carotid arteries of the rat were ligated with silk sutures. The expression of mRNA for COX-1 and COX-2 were detected by the RT-PCR. The first group of animals (n=6) was treated with rofecoxib (10 mg/kg, i.p.) 7 days after operation and the following 7 days. The second group of animals (n=6) was treated with diclofenac sodium (9mg/kg, i.p.) and the third group of animals (n=5) was treated with vehicle (DMSO). TdT-mediated dUTP nick end labeling (TUNEL) technique was performed to estimate delayed cell death. RESULTS: Bilateral carotid artery occlusion (2VO) was shown to induce apoptotic morphology and DNA strand break in hippocampal neurons from 7 days with a peak at 14, 28 days. mRNA of COX-2 appeared in the frontal cortex (14, 28 days) and hippocampus (14, 28, 63 days). Treatment with rofecoxib significantly (p<0.05) attenuated the number of TUNEL-labeled cells in the hippocampus, whereas the cells of the diclofenac treated group were not protected. CONCLUSIONS: We concluded that COX-2 might contribute to cell death of pyramidal cells of the hippocampus of hypoperfusion and selective COX-2 inhibitor, rofecoxib, could prevent the neuronal damage.

Serial study of Apoptosis and Morphologic Change of Retina in Experimental Model of Chronic Retinal Ischemia in Rats

PURPOSE: We investigated the serial developement of programmed cell death or apoptosis as a mechanism of cell death by inducing chronic retinal ischemia in experimental permanent common carotid artery ligation in rats. We also hope this model to be applied in study of normal tension glaucoma or ischemic ocular disease. METHODS: After ligation of both common carotid arteries of rats under anesthesia, they were sacrificed on the 1st, 3rd, 5th, 7th, 14th, 28th, and 63rd day and then enucleation was done. After separating retina, we did TdT-dUTP nick-end labeling (TUNEL)stain and Bax immunochemistry stain to study apoptotic change and we also did hematoxylin eosin stain to evaluate retinal morphologic changes. RESULTS: Apoptotic cells were showed in ganglion cell layer cheifly on TUNEL stain and Bax immunochemistry stain on the first day after ligation of common carotid artery, as time as gone, apoptotic cell increased and then developed in all layers on the 28th day. Cell density decreased in ganlion cell layer, inner nuclear layer, and outer nuclear later on hematoxylin eosin stain on the third day; as time as gone, cell density further decreased and thickness of inner plexiform layer and nuclear layer decreased also. CONCLUSIONS: This result shows that apoptosis has the important role in the cell death at the ischemic retina. The results of this study will also provide baseline information for the further study on normal tension glaucoma or ocular ischemic diseases compared to transient retinal ischemia model induced by elevation of intraocular pressure.

Experimental Model of Bilateral Carotid Artery Occlusion: a Serial Study of the Optic Nerve in the Rat

PURPOSE: This study was performed to examine the serial alteration of the optic nerve in chronic ischemia-induced brain injury of albino rat, which might be an experimental model of ischemia-induced optic nerve disease and vasogenic glaucoma in human. METHODS: We ligated bilateral common carotid arteries so that the brain and optic nerve had permanent ischemic injuries. Serial alteration of the optic nerve was studied on postoperative 1 day, 3 day, 5 day, 1 week, 2 week, 4 week and 9 week. After fixing the brain by perfusing formaline through the left ventiricle, we dissected the brain and optic nerve and then made specimen for Hematoxilin-Eosin (HE) stain to observe the histopathology of the optic nerve. Kluiver-Barrera (KB) stain was performed to qualify the myelin injury and optic nerve injury status. RESULTS: The HE stain specimen showed increased spaces in the nerve fiber layer and increased number of vacuoles three days after the operation. The optic neve injury became augmented with time. The KB stain showed better-defined configuration of HE stain. CONCLUSIONS: We were able to notice that optic nerve injury was induced by the bilateral common carotid ligation in this chronic ischemic experimental model, which might be an help to the studies of ischemic optic nerve disease, neurodefensive mechanism, and the hemodynamic mechanism of glaucoma in human.

Double-Blind Placebo-Controlled Randomized Clinical Trial of Zolmitriptan in Acute Treatment of Migraine

BACKGROUND: Zolmitriptan (Zomig) is a selective serotonin agonist at the 5-hydroxytryptamine (5-HT1B/1D) receptor that acts both centrally and peripherally in the trigeminal nucleus and axon terminals and at adjacent meningeal vessels. The clinical efficacy of zolmitriptan in adult migraine has been documented in several placebo-controlled studies, but not studied yet in Korea. METHODS: This multicenter, double-blind, placebo-controlled study was directed to evaluate the efficacy and tolerability of a single 2.5-mg dose of zolmitriptan for the acute treatment of a single moderate or severe migraine attack in Korean patients. A sample consisting of 129 outpatients was randomized to receive either zolmitriptan (n=67) or placebo (n=62). RESULTS: The headache response at 2 hours after treatment was significantly greater in patients receiving zolmitriptan than in patients receiving placebo (52.2% versus 30.7%, p<0.05). At 4 hours, the response rate in the zolmitriptan group (91.5%) was significantly higher than in the placebo group (65.6%; p<0.05). Among the nonheadache symptoms, phonophobia was more relieved in the zolmitriptan group than in the placebo group (p=0.038). There were no clinically serious adverse events that were judged by the physicians to be related to zolmitriptan. CONCLUSIONS: The results of this study demonstrate that zolmitriptan tablets 2.5-mg taken for acute migraine attacks are effective and well-tolerated in Korean patients. (J Korean Neurol Assoc 19(1):29~35, 2001

Anterior Callosal Disconnection Syndrome

It has been known that right ACA occlusions can cause callosal disconnection syndrome. A 61-year old right-handed man was admitted because of a left ACA occlusion. MRI showed infarction of the medial frontal cortex and the anterior two-thirds of the corpus callosum. He presented with weakness and gait initiation failure in the right leg with grasp reflex, suspicious alien hand sign, and tactile anomia in the right hand. He was diagnosed with transcortical motor aphasia. He was unable to successfully complete written tasks in response to dictations and writing down spontaneous answers. He wrote down incorrect words and demonstrated paragraphism with his left hand. He could copy simple items but not written words and complex items with his left hand. Finally, he had difficulties in writing answers in response to complex verbal and written commands with his left hand, but preserved the ability to simple verbal commands, somato-sensory, and visually guided tasks. We attribute these results to the anterior callosal disconnection of the right sensorimotor cortex from the left language area.

Measurement of Changes in Cerebral Blood Flow Velocity During Hemodialysis / 대한신장학회잡지

Hemodialysis is a safe and effective treatment for uremic patients but hemodynamic changes during hemodialysis is suggested to be the possible cause of encephalopathy. However, few studies have evaluated the cerebral circulation of and the effects of hemodialysis. Therefore, this study was performed to evaluate the cerebral blood flow by transcranial doppler. The study populations were 12 male patients who ranged in age from 28 to 58 years(mean:57) and were receiving maintenance hernodialysis for 3.8 years(0.5-11.5 years). Mean blood flow velocity(MFV), pulsatility index(PI) and resistance index(RI) were measured in carotid artery(CA), middle cerebral artery(MCA), anterior cerebral artery(ACA) and posterior cerebral artery(PCA) before, during and after hemodialysis. Simultaneously, we also checked variables(body weight, blood pressure, arterial blood gases, hematocrits, and other biochemical parameters) which might affect cerebral blood flow. MFV during(70.5+/-20.3 vs. 60.0+/-211cm/sec) and after(vs. 60.6+/-13.7cm/sec, p<0.01) hemodialysis in CA showed significant reduction as compared to the that of before hemodialysis, but other vessels(MCA, ACA and PCA) showed no significant changes. There were no significant changes in PI and RI before, during and after hemodialysis. Body weight, PaCO(2), blood urea nitrogen and hematocrit changed significantly during and after hemodialysis as compared to those of before hemodialysis, but correlation between changes of MFV and these variables was not observed. Hemodialysis and its associated physiologic changes are not associated with cerebral blood flow, and this result suggests the well-preservation of autoregulation of cerebral blood flow during and after hemodialysis.

Stable Xenon-CT Cerebral Blood Flow Imaging in Patients with Cerebral nfarction

BACKGROUND: Stable xenon-CT has been known to be a useful technique for measuring cerebral blood flow (CBF) and its direct correlation with CT anatomy. We evaluated the usefulness and limitations of stable xenon-CT cerebral hemodynamic status. METHODS: Xenon-CT was administered to 23 patients. Ten were normal controls and 13 were stroke patients (acute 4, subacute 5, chronic 2, hemorrhagic 2). Time dependent Xenon concentrations within various tissue segments of the brain was used to derive both the local partition-coefficient (lamda) and CBF in each tissue volume (voxel) of the CT image. RESULTS: In the controls, the regional CBF (rCBF) (ml/100 gm/min) was as follows: frontal 22.9+/-7.3(Mean+/-SD), inferior temporal 23.9+/-3.2, superior temporal 27.4+/-7.3, parietal 30.0+/-10.1, occipital 24.3+/-8.4, cerebellar hemisphere 24.3+/-8.3, thalamus 31.1+/-7.1, and corona radiata 18.1+/-4.7. The cortical differences was within 10%. In the stroke patients, the rCBF in the infarcted area ranged from 0 to 26.5 ml/100 gm/min and interhemispheric cortical difference was above 50%. The routine CT revealed no abnormalitiy, particularly in acute stroke (within 6 hours after onset). However, a xenon-CBF showed perfusion defect which correlated with clinical signs. CONCLUSIONS: With xenon CT, CBF can be obtained within a few hours of stroke onset, result of which can be correlated with CT. In an acute stroke state, a Xenon-CBF map can be a more sensitive method than routine CT imaging. Low value of blood-flow and patient's in cooperation may limit use of Xe-CT.