• Title/Summary/Keyword: Cortical activity

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Changes in Cerebral Blood flow Following Fermented Garlic Extract Solution with High Content of Nitrite (흰쥐에서 고용량 아질산이온 함유 마늘 발효농축액에 의한 뇌혈류 변화)

  • Yu, Hyeok;Rong, Zhang Xiao;Koo, Ho;Chun, Hyun Soo;Yoo, Su Jin;Kim, Min Sun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.34 no.6
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    • pp.326-333
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    • 2020
  • Nitrate-nitrite-nitric oxide (NO) pathway is a major alternative source of NO and is essential for NO - dependent physiological functions in body. Food supplements having nitrate/nitrite can improve metabolic syndromes including hypertension through antioxidant activity or vasodilation. The purpose of this study was to observe the effects of fermented garlic (F. garlic) having high concentration of NO2- on changes in blood flow and nitric oxide synthesis in the cerebral cortex of rodents. The generation of nitric oxide detected by a chemi-luminescence detector was higher in F. Garlic compared with NaNO2 solution under artificial gastric juice with pH 2.0. Ether F. garlic or NaNO2 diluted with artificial cerebrospinal fluid was directly applied into around the needle probe of laser Doppler flow meter that was located on epidural surface of the cortex. Direct application of F. garlic resulted in increase of cerebral blood flow detected by a laser Doppler flow meter with a dose-dependent manner. Compared with NaNO2 solution, F. garlic produced changes in cerebral blood flow at lower concentration of NO2-. Pretreatment of methylene blue, a guanylyl cyclase inhibitor prevented upregulation of cerebral blood flow by the treatment of F. garlic. In addition, the application of F. garlic with 250, 500ppm of NO2- caused significantly the production of NO in the cortical tissue but NaNO2 solution with 500ppm of NO2- did not. In summary, these results suggested that F. garlic with high content of NO2- induce increase in cerebral blood flow through nitric oxide-dependent signal pathway.

The Effect of Transcranial Direct Current Stimulation over the Primary Somatosensory Cortex in Patients with Chronic Stroke on Somatosensory and Upper Limb Function for Improving Life Care (만성 뇌졸중 환자를 대상으로 한 일차 체성 감각 피질을 자극한 경두개 직류 전류 자극이 라이프 케어 증진을 위한 체성감각과 상지기능에 미치는 영향)

  • Kim, Sun-Ho
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.6
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    • pp.269-277
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    • 2020
  • The purpose of this study is to investigate the recovery of sensation and the restoration of upper limb function according to transcranial direct current stimulation over the primary somatosensory cortex in patients with chronic stroke with sensory deficit. 20 patients with chronic stroke divided into 10 experimental groups and 10 control groups. Patients received transcranial direct current stimulations over the primary somatosensory cortex on the side of the stroke lesion, and The control group applied sham tDCS to the same location. Intervention was conducted 5 times a week, 20 minutes per session for a total of 2 weeks. Assessment was performed using the Erasmus MC modifications to the Nottingham Sensory Assessment(EmNSA), Semmes-Weinstein monofilament examination(SWME) for somatosensory, and Fugle-Meyer Assessment(FMA), Motor Activity Log(MAL), and accelerometer for upper extremity function. Assessment was conducted before and after the intervention. As a result of the study, the experimental group showed a significant improvement in the overall tactile sense, proprioception, cortical sense, and perception sensitivity than the control group, and showed a statistically significant difference in the usage amount of the upper limb. Based on the results of this study, it is thought that the possibility of effective clinical application of transcranial direct current stimulation for recovery of somatosensory and upper extremity function is thought to be increased.

Abnormal Behavior Controlled via GPR56 Expression in Microglia (미세아교세포에서 GPR56 발현에 의한 이상 행동)

  • Hyunju Kim
    • Journal of Life Science
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    • v.33 no.6
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    • pp.455-462
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    • 2023
  • During pregnancy, maternal immune activation (MIA) from infection increases the risk of neurodevelopmental diseases, including schizophrenia and autism spectrum disorders. MIA induced by polyinosinic-polycytidylic acid (poly (I:C)) and lipopolysaccharide (LPS) in animal experiments has led to offspring with abnormal behaviors and brain development. In addition, it has recently been reported that microglia, which reside in the brain and function as immune cells, play an important role in behavioral abnormalities and brain development in MIA-induced offspring. However, the underlying mechanism remains unclear. In this study, we investigated whether microglia-specific inhibition of GPR56, a member of the G protein-coupled receptor (GPCR) family, causes behavioral abnormalities in brain development. First, MIA induction did not affect the microglia population, but when examining the expression of microglial GRP56 in MIA-induced fetuses, GPR56 expression was inhibited between embryonic days 14.5 (E14.5) and E18.5 regardless of sex. Furthermore, microglial GPR56-suppressed mice showed abnormal behaviors in the MIA-induced offspring, including sociability deficits, repetitive behavioral patterns, and increased anxiety levels. Although abnormal cortical development such as that in the MIA-induced offspring were not observed in the microglial GPR56-suppressed mice, their brain activity was observed through c-fos staining. These results suggest that microglia-specific GPR56 deficiency may cause abnormal behaviors and could be used as a biomarker for the diagnosis and/or as a therapeutic target of behavioral deficits in MIA offspring.

Functional MRI of Visual cortex in the Patients with Occipital Lobe Ischemia (후두엽의 허혈성 뇌졸중 환자에서 시각피질의 기능적 자기공명영상)

  • 이영준;정태섭;윤영수;한승한;조영재;배준호
    • Investigative Magnetic Resonance Imaging
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    • v.3 no.2
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    • pp.173-178
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    • 1999
  • Purpose : To evaluate the usefulness of functional MRI (fMRI) of visual cortex in patients with ischemic infarction in the occipital lobe. Materials and Methods : Four patients with the symptoms and signs of visual cortical ischemia were included. Functional MRI was performed by 2D-FLASH technique with the parameter of 90/56msec TR/TE, $40^{\circ}$ flip angle, $240{\times}240{\;}FOV,{\;}64{\times}128$ matrix number, 8.32 seconds acquisition time, 8mm slice thickness. An axial slice including both visual cortices was selected and alternative activation and resting of the visual cortex was performed using red color photostimulator. all patients undertook visual field test, and vascular abnormality was examined by MRA (n=4) and DSA (n=2). fMRI results were compared with the results of a visual field test, conventional MRI and cerebral angiography. Results : On fMRI, decreased activity of the visual cortex was found in the occipital lobe corresponding to stenosis of the posterior cerebral artery or its branch noted on angiogram. However, 2 of 4 patients showed no abnormal findings on conventional MRI. Visual field defect was noted in 3 patients, one and of whom showed no abnormality on conventional MRI and diffusion-weighted image, but revealed decreased activity in the corresponding visual cortex on fMRI. Conclusion : fMRI may be a sensitive method for detection of the status of decreased blood flow or vascular reserve which other methods can not.

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Effects of NG-monomethyl-L-arginine and L-arginine on cerebral hemodynamics and energy metabolism during reoxygenation-reperfusion after cerebral hypoxia-ischemia in newborn piglets (급성 저산소성 허혈성 뇌손상이 유발된 신생자돈에서 재산소-재관류기 동안 NG-monomethyl-L-arginine과 L-arginine이 뇌의 혈역학 및 에너지 대사에 미치는 영향)

  • Ko, Sun Young;Kang, Saem;Chang, Yun Sil;Park, Eun Ae;Park, Won Soon
    • Clinical and Experimental Pediatrics
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    • v.49 no.3
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    • pp.317-325
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    • 2006
  • Purpose : This study was carried out to elucidate the effects of nitric oxide synthase(NOS) inhibitor, NG-monomethyl-L-arginine(L-NMMA) and nitric oxide precursor, L-arginine(L-Arg) on cerebral hemodynamics and energy metabolism during reoxygenation-reperfusion(RR) after hypoxia-ischemia(HI) in newborn piglets. Methods : Twenty-eight newborn piglets were divided into 4 groups; Sham normal control(NC), experimental control(EC), L-NMMA(HI & RR with L-NMMA), and L-Arg(HI & RR with L-Arg) groups. HI was induced by occlusion of bilateral common carotid arteries and simultaneously breathing with 8 percent oxygen for 30 mins, and followed RR by release of carotid occlusion and normoxic ventilation for one hour. All groups were monitored with cerebral hemodynamics and cytochrome $aa_3$ (Cyt $aa_3$) using near infrared spectroscopy(NIRS). $Na^+$, $K^+$-ATPase activity, lipid peroxidation products, and tissue high energy phosphate levels were determined biochemically in the cerebral cortex. Results : In experimental groups, mean arterial blood pressure, $PaO_2$, and pH decreased, and base excess and blood lactate level increased after HI compared to NC group(P<0.05). These variables subsequently returned to baseline after RR except pH. There were no differences among the experimental groups. In NIRS, oxidized hemoglobin($HbO_2$) decreased and hemoglobin(Hb) increased during HI(P<0.05) but returned to base line immediately after RR; 40 min after RR, the $HbO_2$ had decreased significantly compared to NC group(P<0.05). Changes of Cyt $aa_3$ decreased significantly compared to NC after HI and recovered at the end of the experiment. Significantly reduced cerebral cortical cell membrane $Na^+$, $K^+$-ATPase activity and increased lipid peroxidation products(P<0.05) were not improved with L-NMMA or L-Arg. Conclusion : These findings suggest that NO is not involved in the mechanism of HI and RR brain damage during the early acute phase of RR.

Effect of Short Term Treatment with Different Dosage of Inhaled Flucatisone Propionate on Basal Cortisol Concentration (단기간 Fluticasone Propionate 투여 용량에 따른 가저 코르티솔 농도의 변화)

  • Kim, Hyun-Jung;Kim, Hyoung-Sik;Lee, Hong;Moon, Sung-Gi;Lim, Seok-Tae;Park, Ji-Hyun;Lee, Heung-Bum;Lee, Yong-Chul;Rhee, Yang-Keun
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.5
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    • pp.1063-1071
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    • 1997
  • Backgroung : The efficacy of oral corticosteroids in the treatment of chronic asthma is undisputed, but their long-term use is associated with adverse side-effects, including supression of the hypothalamic-pituitary adrenal axis function, osteoporosis, weight gain, hypertension and impaired glucose tolerance. The introduction of inhaled corticosteroids in the early 1970's represented a significant therapeutic advance in the management of asthma, since these compounds combined high topical potency with low systemic activity. Fluticasone propionate is a new topically active synthetic glucocorticosteroid that combinds a high degree of efficacy with negligible systemic bioavailability. This study was perfomed to determine the effect of inhaled fluticasone propionate on the adreocortical supression in patients with bronchial asthma or chronic obstructive pulmonary disease. Method : The adrenocortical function was assessed by measurement of plasma cortisol concentration at 8 o'clock in morning and free cortisol in 24 hour urine collection at interval. Absolutely, no steroid was taken during pretreatment period of 10days. There after each subject inhaled fluticasone aerosol, in daily doses of 500 or 1000micrograms for 12days. The dose was delivered by metered dose inhaler(MDI). Results : The serum cortisol and 24hour urinary free cortisol were not decreased during the treatment period in patients with inhaled fluticasone propionate in daily doses of 500 micrograms. In contrast, serum cortisol was significantly decreased on 9th and 12th day(p less than 0.05). And, 24hour urinary free cortisol was also significantly decreased on 3rd and 12th day of treatement period(p less than 0.05) in patients with inhaled fluticasone in daily doses of 1000 micrograms. Conclusion : These results suggested that endogenous cortisol secretion was not supressed after short-term inhalation of fluticasone in daily dose of 500 micrograms, but in daily dose of 1000 micrograms, the endogenous cortisol secretion was supressed.

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Utility of $^{99m}Tc$-MAG3 Perfusion Indices in the Evaluation of Renal Transplant Function During Early Post-transplantation Period (이식 초기 이식신 기능 평가에서 $^{99m}Tc$-MAG3 신관류 지표의 유용성)

  • Kim, Sung-Hoon;Chung, Soo-Kyo
    • The Korean Journal of Nuclear Medicine
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    • v.34 no.6
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    • pp.497-507
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    • 2000
  • Purpose: We have examined the utility of $^{99m}Tc$-MAG3 perfusion indices for assessing renal graft function in early post-transplantation period. Materials and Methods: Our study included 80 renal transplant recipients (48 men and 32 women, mean age: 40.3 years). Diagnosis was based on biopsy, laboratory data and clinical course. Renal scintigraphy (RS) was obtained using 100 MBq of $^{99m}Tc$-MAG3 from 11 days to 23 days of kidney transplantation. We measured 5 indices in whole-kidney (WK) and cortical (C) renograms; Hilson's perfusion index (PI), transplant perfusion index (TP) and transplant function index (TF) as perfusion parameter, and the time to peak activity (Tmax) and the ratio of renal counts at 20 min to that at 3 min (K20/3) as functional parameter. Results: The diagnoses at the day of RS were normal graft (NG) in 44, acute rejection (AR) in 14, acute tubular necrosis (ATN) in 10, and Cyclosporine A nephrotoxicity (CsA) in 12. TP and TF were significantly decreased in AR, ATN and CsA, compared to those in NG. K20/3 of AR and ATN wore significantly greater than that of NG. WK-Tmax of AR was significantly longer than that of NG. K20/3 of AR and C-K20/3 of ATN were significantly prolonged relative to those of CsA. There were no statistically significant perfusion indices among complication groups. Conclusion: TP and TF reflecting microperfusion and initial tubular extraction are reliable in assessing graft function. However, it is required to correlate perfusion indices with functional indices and clinical course in differentiating from one another among complication groups.

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Autoradiographic Studies on the Inhibitory Effect of Dibutyryl Cyclic AMP on Mouse Oocyte Maturation in Vitro (Dibutyryl Cyclic AMP가 생쥐여포난자의 성숙에 미치는 억제효과에 관한 자기방사법적 연구)

  • Choi, Choon-Keun
    • Applied Microscopy
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    • v.7 no.1
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    • pp.21-43
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    • 1977
  • This experiment was undertaken in order to localize the labeled dbcAMP (dibutyryl cyclic AMP) in oocytes whose development has been suppressed by cold dbcAMP for 6 or 19 hours in vitro. Mouse oocytes were obtained from the ovaries of 3-4 week old A strain female mice, by puncturing the Graafian follicles in the modified Krebs-Ringer bicarbonate salt solution under the dissecting microscope. Those oocytes which have intact germinal vesicle were cultured in the basic culture medium supplemented with 0.4% bovine serum albumin (BSA). Cultivation of the oocytes was carried out in a microtube developed by Cho (1974). The cultures were then incubated in a humidified 5% $CO_2$ incubator maintained at $37^{\circ}C$ for 6 or 19 hours (Donahue, 1968). DbcAMP was added to culture medium for a final concentration of 100ug/ml, and $^3H-dbc$ AMP (specific activity 13 Ci/mM) for a final concentration of $40{\mu}Ci/ml$ was also added to the medium. For electron microscopic autoradiography, those oocytes recovered from the culture were washed with phosphate buffer (pH 7.4), and immediately prefixed in a 2.5% glutaraldehyde overnight and postfixed for 2 hours at $4 ^{\circ}C$ in 1% osmium tetroxide in phosphate buffer with pH 7.4 (Palade, 1952). After fixation, the materials were dehydrated in graded alcohol series and embedded in Epon 812 mixture based on the standard procedures (Luft, 1961). The thin sections $600-700{\AA}$ thick were mounted on the grids of 200 meshes. The grids containing sections were coated with a nuclear emulsion Kodak NTB-3 and stored in a cold dark box (at $4^{\circ}C$) for 3 weeks. After exposure, the samples were developed with Kodak D-19 and stained with uranyl acetate and lead citrate. Routine observation was made with Hitachi HU-11E electron microsocope. The results of the observation were as followings: 1. It was found that the labeled dbcAMP penetrated the egg plasma membrane and dispersed at random in the cytoplasm. 2. It was also observed that most of the labeled dbcAMP was attached to microfibrillar lattices portion of the oocyte cytoplasm. There fore, it is presumed that the receptor of the dbcAMP is localized in the microfibrillar lattices of the oocyte. 3. It also seems that some other cell organells such as mitochondria, Golgi complex, cortical granules are not directly related to the action of the dbcAMP. 4. The labeled dbcAMP was neither observed in the membrane nor in the nucleus. Therefore, it seems that there is no relationship between the concentration of dbcAMP and the nuclear membranous permeability. 5. There was no difference in number of dbcAMP particles when oocytes were cultured for 6 hours and 19 hours. 6. However, it was observed that, in same of the oocytes suppressed in germinal vesicle by dbcAMP for 19 hours, cell organells were moved and concentrated to a small portion of the cytoplasm, and that the morphology of the organells greatly changed to an abnormal. form. Therefore, it is supposed that those oocytes were in the process of degeneration. From the above results, it is expected that dbcAMP penetrated the egg membrane and was bound to the receptor which seems to be located in the microfibrillar lattiees portion, and that this dbcAMP-receptor complex inhibited some enzyme system of the oocytes which are essential for the germinal vesicle breakdown.

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