• IMMUNE NETWORK
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• 제11권3호
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• pp.135-154
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• 2011

The great discovery of microRNAs (miRNAs) has revolutionized current cell biology and medical science. miRNAs are small conserved non-coding RNA molecules that post-transcriptionally regulate gene expression by targeting the 3' untranslated region of specific messenger RNAs for degradation or translational repression. New members of the miRNA family are being discovered on a daily basis and emerging evidence has demonstrated that miRNAs play a major role in a wide range of developmental process including cell proliferation, cell cycle, cell differentiation, metabolism, apoptosis, developmental timing, neuronal cell fate, neuronal gene expression, brain morphogenesis, muscle differentiation and stem cell division. Moreover, a large number of studies have reported links between alterations of miRNA homeostasis and pathological conditions such as cancer, psychiatric and neurological diseases, cardiovascular disease, and autoimmune disease. Interestingly, in addition, miRNA deficiencies or excesses have been correlated with a number of clinically important diseases ranging from cancer to myocardial infarction. miRNAs can repress the gene translation of hundreds of their targets and are therefore well-positioned to target a multitude of cellular mechanisms. As a consequence of extensive participation in normal functions, it is quite logical to ask the question if abnormalities in miRNAs should have importance in human diseases. Great discoveries and rapid progress in the past few years on miRNAs provide the hope that miRNAs will in the near future have a great potential in the diagnosis and treatment of many diseases. Currently, an explosive literature has focussed on the role of miRNA in human cancer and cardiovascular disease. In this review, I briefly summarize the explosive current studies about involvement of miRNA in various human cancers and cardiovascular disease.

• 한국발생생물학회지:발생과생식
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• 제14권1호
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• pp.35-41
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• 2010

Mammalian reproduction is regulated by a feedback circuit of the key reproductive hormones such as GnRH, gonadotropin and sex steroids on the hypothalamic-pituitary-gonadal axis. In particular, the onset of female puberty is triggered by gain of a pulsatile pattern and increment of GnRH secretion from hypothalamus. Previous studies including our own clearly demonstrated that genistein (GS), a phytoestrogenic isoflavone, altered the timing of puberty onset in female rats. However, the brain-specific actions of GS in female rats has not been explored yet. The present study was performed to examine the changes in the activities of GnRH neurons and their neural circuits by GS in female rats. Concerning the drug delivery route, intracerebroventricular (ICV) injection technique was employed to eliminate the unwanted actions on the extrabrain tissues which can be occurred if the testing drug is systemically administered. Adult female rats (PND 100, 210-230 g BW) were anaesthetized, treated with single dose of GS ($3.4{\mu}g$/animal), and sacrificed at 3 hrs post-injection. To determine the transcriptional changes of reproductive hormone-related genes in hypothalamus, total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). ICV infusion of GS significantly raised the transcriptional activities of enhanced at puberty1 (EAP-1, p<0.05), glutamic acid decarboxylase (GAD67, p<0.01) which are known to modulate GnRH secretion in the hypothalamus. However, GS infusion could not change the mRNA level of nitric oxide synthase 2 (NOS-2). GS administration significantly increased the mRNA levels of KiSS-1 (p<0.001), GPR54 (p<0.001), and GnRH (p<0.01) in the hypothalami, but decreased the mRNA levels of LH-$\beta$ (p<0.01) and FSH-$\beta$ (p<0.05) in the pituitaries. Taken together, the present study indicated that the acute exposure to GS could directly activate the hypothalamic GnRH modulating system, suggesting the GS's disrupting effects such as the early onset of puberty in immature female rats might be derived from premature activation of key reproduction related genes in hypothalamus-pituitary neuroendocrine circuit.

• Journal of Korean Neurosurgical Society
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• 제30권12호
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• pp.1375-1380
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• 2001

Objective : The authors analyzed the incidence, the cause and the prognosis of hydrocephalus following aneurysmal subarachnoid hemorrhage to evaluate the risk factors of hydrocephalus and to provide the proper treatment method for hydrocephalus following aneurysmal subarachnoid hemorrhage. Methods : The 505 cases of subarachnoid hemorrhage followed by aneurysmal surgery from January 1990 to May 1999, were divided into shunt group and shunt-free group and we were reviewed for the clinical status, Fisher's grade, brain CT findings and prognosis. Results : The incidence of acute hydrocephalus was 37.2% of patients and 18.9% to developed chronic hydrocephalus. Shunt surgery due to chronic hydrocephalus was required in 6.5% of patients. We found following variables were significantly related to shunt-dependent hydrocephalus : high Hunt-Hess and Fisher grade, initial CT findings of intraventricular hemorrahge, posterior circulation aneurysm, preoperative rebleeding, delayed ischemic deficits, and initial high ventricular size index. There were no statistically significant relationships between shunt-dependent hydrocephalus and patient age or sex, timing of operation. The previous hypertension was not related to shunt dependent hydrocephalus. Prognosis in shunt group showed poor result. Conclusion : The risk factors of hydrocephalus following aneurysmal subarachnoid hemorrhage are high Hunt-Hess grade, high Fisher's grade, aneurysms of posterior circulations, preoperative aneurysmal rebleeding, delayed ischemic deficits, initial CT findings of intraventricular hemorrahge and initially increased ventricular size. The patients with these factors should the carefully observed and managed accordingly due to poor prognosis related to hydrocephalus requiring shunt operation.

• The Korean Journal of Physiology and Pharmacology
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• 제18권6호
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• pp.517-524
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• 2014

Phasic and tonic ${\gamma}$-aminobutyric acidA ($GABA_A$) receptor-mediated inhibition critically regulate neuronal information processing. As these two inhibitory modalities have distinctive features in their receptor composition, subcellular localization of receptors, and the timing of receptor activation, it has been thought that they might exert distinct roles, if not completely separable, in the regulation of neuronal function. Inhibition should be maintained and regulated depending on changes in network activity, since maintenance of excitation-inhibition balance is essential for proper functioning of the nervous system. In the present study, we investigated how phasic and tonic inhibition are maintained and regulated by different signaling cascades. Inhibitory postsynaptic currents were measured as either electrically evoked events or spontaneous events to investigate regulation of phasic inhibition in layer 2/3 pyramidal neurons of the rat visual cortex. Tonic inhibition was assessed as changes in holding currents by the application of the $GABA_A$ receptor blocker bicuculline. Basal tone of phasic inhibition was maintained by intracellular $Ca^{2+}$ and $Ca^{2+}$/calmodulin-dependent protein kinase II (CaMKII). However, maintenance of tonic inhibition relied on protein kinase A activity. Depolarization of membrane potential (5 min of 0 mV holding) potentiated phasic inhibition via $Ca^{2+}$ and CaMKII but tonic inhibition was not affected. Thus, phasic and tonic inhibition seem to be independently maintained and regulated by different signaling cascades in the same cell. These results suggest that neuromodulatory signals might differentially regulate phasic and tonic inhibition in response to changes in brain states.

• Perspectives in Nursing Science
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• 제2권1호
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• pp.76-91
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• 2005

Stroke patients often develop post stroke sequelae when they survive. Post stroke fatigue and emotional disturbances including depression are common along with motor dysfunction. However, medical personnel have paid relatively little attention to emotional changes and the presence of fatigue following strokes. Post-stroke fatigue was common, occurring in 57% of the patients in our series. The post-stroke fatigue appears to be related to the pre-stroke fatigue, physical disability and post stroke depression (PSD) although the relation to the lesion location remains elusive. The prevalence of post-stroke emotional disturbance has been reported to range from 12% to 64%. The wide variation in the frequency of post stroke depression may be related to methodological heterogeneity in items such as the criteria for depression, the timing of assessment, and the study population. Emotional incontinence, which is characterized by inappropriate or excessive laughing or crying is also common. The incidence of and factor related to this post-stroke emotional incontinence (PSEI) also remains unclear. We reported that out-patients with single, unilateral stroke, 18% had PSD and 34% had PSEI. Although both PSD and PSEI were related to motor dysfunction and location (anterior vs. posterior cortex) of the lesion, the latter was a stronger determinant for PSD. PSEI was more closely associated with subcortical strokes than was PSD. Another manifestation of post stroke patients is the occurrence of post stroke anger proneness (PSAP). They may become easily irritated, impulsive, less generous, and prone to be angry or aggressive at others. We also have reported the PSAP which seems to be closely associated with the presence of PSEI. The lesion distribution appears to be also similar. Both PSEI and PSAP respond well to serotonin reuptake inhibitors suggesting that these symptomsmay be possibly related to the alteration of serotonin after brain injury. Likewise, PSAP also produces a great deal of frustration and embarrassment among patients and caregivers. In summary, emotional disturbances such as depression, emotional incontinence, anger-proneness and fatigue are fairly common but under-recognized sequelae of stroke. These emotional disturbances decrease the quality of life of the patients and caregivers, and may adversely affect the overall prognosis. Therefore, these problems must be appropriately recognized and alleviated. Finding strategies to relieve the symptoms is imperative by understanding the causative factors in individual patient.

• 대한두개안면성형외과학회지
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• 제21권5호
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• pp.309-314
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• 2020

Reconstructions of extensive composite scalp and cranial defects are challenging due to high incidence of postoperative infection and reconstruction failure. In such cases, cranial reconstruction and vascularized soft tissue coverage are required. However, optimal reconstruction timing and material for cranioplasty are not yet determined. Herein, we present a large skull defect with a chronically infected wound that was not improved by repeated debridement and antibiotic treatment for 3 months. It was successfully treated with anterolateral thigh (ALT) free flap transfer for wound salvage and delayed cranioplasty with a patient-specific polyetheretherketone implant. To reduce infection risk, we performed the cranioplasty 1 year after the infection had resolved. In the meantime, depression of ALT flap at the skull defect site was observed, and the midline shift to the contralateral side was reported in a brain computed tomography (CT) scan, but no evidence of neurologic deterioration was found. After the surgery, sufficient cerebral expansion without noticeable dead-space was confirmed in a follow-up CT scan, and there was no complication over the 1-year follow-up period.

• 전자공학회논문지
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• 제50권9호
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• pp.179-185
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• 2013

본 논문에서는 시각에 대해 반응하는 운동 행동의 효과를 분석하기 위해서 응답속도정합-유발전위(RTA-ERP: Response Time Aligned-Event Related Potential)를 모델링하고, RTA-ERP의 진폭과 응답 속도를 이용하여 사이먼 효과를 분석하였다. 건강한 성인 15명(남성 9명, 여성 6명, 평균 연령 31세)을 대상으로, 같은 숫자에 대한 다른 숫자를 찾아 반응하는 '양자극방안' 실험을 7분 동안 수행하였다. 실험결과 제안된 RTA-ERP는 기존의 ERP에 비해 뇌에서의 처리시간 차이에 따른 변이를 보상할 수 있었으며, 향상된 LRP(Lateralized Readiness Potential)와 Pe(Error Related Positivity)를 나타내었다. '일치', '불일치' 시험 패턴에 대하여 '일치'에 대한 RTA-ERP의 진폭과 응답속도는 각각 '불일치'보다 컸으며 진폭은 $0.03{\mu}V$ 크고 반응속도는 43 ms 만큼 빨랐다. 응답속도에 따른 동기 시점을 보정하여 정합함에 따라, RTA-ERP의 진폭특성은 사이먼 효과의 특징인 ERP의 P300 진폭과 대응함을 확인하였다.

• The Journal of Korean Physical Therapy
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• 제26권4호
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• pp.234-239
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• 2014

Purpose: The purpose of this study is to use P300 latency to determine whether methods of motor learning in terms of massed and distributed practice can affect motor sequential learning in healthy adults. Methods: Twenty-four healthy subjects participated in this study. They were randomly allocated into three groups: a 10 minute, a 12 hour, and a 24 hour group. In the SRT task, eight numbers were adopted as auditory stimuli. During an experiment, participants were instructed to press the matching key as quickly and accurately as possible when one of the eight numbers was presented randomly. The subjects practiced for three sessions, each of which comprised five blocks of 40 serial reaction time tasks. While they practiced during these three sessions, P300 latency was measured. The data were analyzed using ANCOVA. Results: The P300 latency of Fz, Cz, and Pz decreased in all groups except for the Fz area of the 10 min group. Overall, the P300 latency of the 10 min group showed a smaller decrease compared with the 12 hr and 24 hr groups. Statistically, no significant differences in the Fz and Cz areas were observed among the three groups. The P300 latency in the Pz area of the 10 min group showed a significantly smaller decrease compared with the other groups. Conclusion: These findings suggest that short-term sequential motor training can alter brain functions such as the P300 latency. We also found that better acquisition of a motor skill was obtained with distributed practice of a task than with massed practice.

• 한국식품영양과학회:학술대회논문집
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• 한국식품영양과학회 2001년도 International Symposium on Food,Nutrition and Health for 21st Century
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• pp.22-37
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• 2001

Melatonin is secreted during the hours of darkness and is thought to influence the circadian and seasonal timing of a variety of physiological processes. Serotonin N-acetyltransferase (AA-NAT) which is found to be expressed in pineal gland, retina, and various tissues, catalyses the conversion of serotonin to N-acetylserotonin and is known as the rate-limiting enzyme in the biosynthetic pathway of melatonin. The compounds that modulate the activity of AA-NAT can be used to treat serotonin-and melatonin-related diseases such as insomnia, depression and seasonal affective disorders (SAD). Several assay methods have been developed by which to measure AA-NAT activity. We have also developed a simple, rapid and sensitive AA-NAT assay method that takes advantage of differences in the organic solubilities between acetyl CoA and N-acetyltryptamine. We screened modulators of AA-NAT activity from the water extracts of the medicinal plants. We found MNP1005 which strongly inhibited the activity of AA-NAT ($IC_{50}$=2.2$\mu$M). Enzyme inhibitory kinetic studies revealed that MNP1005 exhibited a noncompetitive inhibition toward tryptamine. The antidepressant effect of MNP1005 was investigated on behavioral despair test so called forced swimming test (FST). MNP1005 significantly increased swimming behavior by reducing immobility with treatment of 10 mg/kg when compared to the vehicle-treated control group (P < 0.05). This suggests that MNP1005 possesses antidepressant activity. The influence of chronic MNP1005 treatment on the expression of brain-derived neurotrophic factor (BDNF) was examined by in situ hybridization and Northern blot. Chronic treatment of MNP1005 blocked the downregulation of BDNF mRNA in the frontal cortex and other cortex regions in response to restraint stress.

• 동의생리병리학회지
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• 제23권6호
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• pp.1497-1502
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• 2009

The cerebellum processes input from other areas of the brain, spinal cord and sensory receptors to provide precise timing for coordinated, smooth movements of the skeletal muscular system. A stroke affecting the cerebellum may cause vertigo, nausea, balance and coordination problems. The papers on central vertigo caused by cerebellar infarction were reported by Kim, Ku, Ko, Choi, and Han. Their cases were classed as Heo hoon, Dam hoon, and Sangchopungyeul yeul dam, and they treated with Jaeumkunbi-tang, Taeksa-tang, Cheonghunwhadam-tang gami, Cheonginwhadam-tang, Hachulbosim-tang. In this paper, three patients who suffered from vertigo were diagnosed as cerebellar infarction. They felt too giddy to walk without any help. After Oriental medical treatment based on Dongeuibogam, their sequelae of cerebellar infarction - vertigo, nausea, ataxia - had improved dramatically. So we report these cases, and suggest Oriental medical treatment based on Dongeuibogam have effect on cerebellar infarction. But more clinical case reports should be further examined.