• Journal of Korean Neurosurgical Society
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• v.64 no.4
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• pp.665-670
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• 2021

Symptomatic cerebral vasospasm (CVS) and delayed ischemic neurologic deficit (DIND) after unruptured aneurysm surgery are extremely rare. Its onset timing is variable, and its mechanisms are unclear. We report two cases of CVS with DIND after unruptured aneurysm surgery and review the literature regarding potential mechanisms. The first case is a 51-year-old woman with non-hemorrhagic vasospasm after unruptured left anterior communicating artery aneurysm surgery. She presented with delayed vasospasm on postoperative day 14. The second case is a 45-year-old woman who suffered from oculomotor nerve palsy caused by an unruptured posterior communicatig artery (PCoA) aneurysm. DIND with non-hemorrhagic vasospasm developed on postoperative day 12. To our knowledge, this is the first report of symptomatic CVS with oculomotor nerve palsy following unruptured PCoA aneurysm surgery. CVS with DIND after unruptured aneurysm surgery is very rare and can be triggered by multiple mechanisms, such as hemorrhage, mechanical stress to the arterial wall, or the trigemino-cerebrovascular system. For unruptured aneurysm surgery, although it is rare, careful observation and treatments can be needed for postoperative CVS with DIND.

• Korean Journal of Biological Psychiatry
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• v.23 no.1
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• pp.1-11
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• 2016

Development of various antidepressants such as monoamine oxidase inhibitors, tricyclic antidepressants, selective serotonin reuptake inhibitors, serotonin norepinephrine reuptake inhibitors, and noradrenergic and specific serotonergic antidepressant has led to a tremendous progression of pharmaceutical treatment for depression, but still there are some limitations of current antidepressants, such as treatment-resistant depression and delayed onset of antidepressants. The pathogenesis of depression is unclear because depression is a heterogeneous disease state, and the mechanisms of antidepressants remain uncertain as well. Nevertheless, in an attempt to develop novel antidepressants, some trials have been conducted based on the potential biological mechanism discovered in the numerous research results. This review will provide information about the potential novel antidepressants and the current states of clinical studies using them. In particular, some potential novel antidepressants anti-inflammatory agents, antioxidants, anticholinergics, modulators of Hypothalamic Pituitary Adrenal Axis, glutamate, and opioid systems, as well as some neuropeptides such as susbstance P, neuropeptide Y, and galanin will be discussed.

• International Journal of Oral Biology
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• v.43 no.1
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• pp.43-51
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• 2018

$K^+$ channels are key components of the primary and secondary basolateral $Cl^-$ pump systems, which are important for secretion from the salivary glands. Paroxetine is a selective serotonin reuptake inhibitor (SSRI) for psychiatric disorders that can induce QT prolongation, which may lead to torsades de pointes. We studied the effects of paroxetine on a human $K^+$ channel, human ether-a-go-go-related gene (hERG), expressed in Xenopus oocytes and on action potential in guinea pig ventricular myocytes. The hERG encodes the pore-forming subunits of the rapidly-activating delayed rectifier $K^+$ channel ($I_{Kr}$) in the heart. Mutations in hERG reduce $I_{Kr}$ and cause type 2 long QT syndrome (LQT2), a disorder that predisposes individuals to life-threatening arrhythmias. Paroxetine induced concentration-dependent decreases in the current amplitude at the end of the voltage steps and hERG tail currents. The inhibition was concentration-dependent and time-dependent, but voltage-independent during each voltage pulse. In guinea pig ventricular myocytes held at $36^{\circ}C$, treatment with $0.4{\mu}M$ paroxetine for 5 min decreased the action potential duration at 90% of repolarization ($APD_{90}$) by 4.3%. Our results suggest that paroxetine is a blocker of the hERG channels, providing a molecular mechanism for the arrhythmogenic side effects of clinical administration of paroxetine.

• Annals of Clinical Neurophysiology
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• v.1 no.2
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• pp.99-105
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• 1999

Background and Objectives : The Motor evoked potentials (MEP) study may be useful in the evaluation of the degree of impairment in the motor nervous system and in the determination of the prognosis. The purpose of this study is to evaluate the status of central nervous system in acute and subacute state of cerebral ischemia by comparing the changes of MEP in the initial and follow-up study. Methods : Twenty patients with hemiparesis caused by ischemic stroke were recruited for this study. We tested MEP within 7 days and followed-up after 14 days after symptom onset. The cerebral motor cortex area, cervical area for upper extremity and lumbar area for lower extremity were stimulated by transmagnetic stimulator. The central motor conduction time(CMCT) was measured with the difference in MEP caused by stimulating the vertical area and spinal area. The CMCT of hemiparetic patients were classified into three groups-normal, delayed, and no evoked MEP groups. Results : The CMCT in hemiparetic side of acute ischemic stroke patients were singnificantly delayed (P < 0.05) compared with the control group. The CMCT of hemiparetic side in the follow-up study showed no sinificantly difference in comparison to the control group. The prognosis of motor improvement was better in the groups of delayed MEP than the groups of no evoked MEP. Conclusion : The CMCT of hemiparetic and contralateral sides were delayed in acute ischemic stroke, compared with control group and were returned to normal boundaries in subacute state. But in the most cases with no MEP response in the initial study, also showed no MEP response in the follow-up study. The recovery occurred in the subacute state in cases with mild hemiparesis, whereas recovery did not occur in the subacute stage in case with severe hemiparesis.

• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1593-1603
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• 2023

In deterministic and Monte Carlo transport codes, b-delayed emission is included using a group structure where all of the precursors are grouped together in 6 groups or families, but given the increase in computational power, nowadays there is no reason to keep this structure. Furthermore, there have been recent efforts to compile and evaluate all the available b-delayed neutron emission data and to measure new and improved data on individual precursors. In order to be able to perform a transient Monte Carlo simulation, data from individual precursors needs to be implemented in a transport code. This work is the first step towards the development of a tool to explore the effect of individual precursors in a fissile system. In concrete, individual precursor data is included by expanding the capabilities of the open source Monte Carlo code OpenMC. In the modified code - named Time Dependent OpenMC or OpenMC(TD)- time dependency related to β-delayed neutron emission was handled by using forced decay of precursors and combing of the particle population. The data for continuous energy neutron cross-sections was taken from JEFF-3.1.1 library. Regarding the data needed to include the individual precursors, cumulative yields were taken from JEFF-3.1.1 and delayed neutron emission probabilities and delayed neutron spectra were taken from ENDF-B/VIII.0. OpenMC(TD) was tested in a monoenergetic system, an energy dependent unmoderated system where the precursors were taken individually or in a group structure, and in a light-water moderated energy dependent system, using 6-groups, 50 and 40 individual precursors. Neutron flux as a function of time was obtained for each of the systems studied. These results show the potential of OpenMC(TD) as a tool to study the impact of individual precursor data on fissile systems, thus motivating further research to simulate more complex fissile systems.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2785-2790
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• 2007

This study presents an impedance method of in-vitro characterization of the thrombotic potential of whole blood. Whole blood samples of 0.2 cc were put into a micro-cell with embedded three electrodes immediately after venepuncture at $37^{\circ}C$. Anti-coagulated blood samples were also collected for hematocrit and blood viscosity analyses. The rate of change of electron flow was measured, which indicates the inverse of the thrombotic potential. A sudden decrease in the rate of change of electron flow was observed at a time equal to approximately 110 seconds. This sudden decrease was significantly delayed in anti-coagulated samples. After the sudden decrease, the rate continued to decrease, reaching a minimum value in unadulterated samples while the change in the rate in the anti-coagulated ones was found rather moderate. Based on these preliminary findings, the present method may be of used as a new tool for the diagnosis of the thrombotic potential of whole blood.

• Biomolecules & Therapeutics
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• v.15 no.1
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• pp.7-15
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• 2007

There have been various animal models of skin inflammation. These models have been used for establishing anti-inflammatory activity of the topical agents including cosmetics. Here, the molecular mechanisms of most widely-used animal models of skin inflammation including contact irritation, acute and chronic inflammation, and delayed-type hypersensitivity are summarized. Against these animal models, varieties of plant flavonoids showed anti-inflammatory activity. The action mechanisms of anti-inflammation by topical flavonoids are presented. A therapeutic potential of flavonoids is discussed.

• Journal of Biomedical Engineering Research
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• v.15 no.4
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• pp.407-412
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• 1994

This paper describes the construction of an anisotropic three dimensional ventricular model based on the bidomain model. The cardiac activation process in the normal cardiac cell and the myocardial ischemic cell are simulated by the Huygen's principle. The depolarization process in the myocardial ischemia displays the delayed activation compared to the normal state. The repolarization process is simulated by the myocardial potential at the arbitrary ellapsed time after activation process. Using the potential data, the equivalent cardiac source at the arbitrary time can be computed. In conclusion, this simulation suggests the possibilities of the depolarization and the repolarization process in the normal and abnormal myocardiac cells.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.7
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• pp.1590-1598
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• 1997

The paper first introduces the new concept of potential diversity and signal decomposability, which establish a foundaton to generalize the existing concepts of path and frequency diversities. Then it presents a new DS/CDMA system called chip-spreading OCDM system, which is an embodiment of the petential diversity concept that combines the path diversity of the DS/CDMA system and the frequency diversity of the OFDM/CDMA system. In the chip-spreading OCDM system the chip sequences in each symbol interval are first converted into aralled streams, which then simultaneously modulate different orthogonal Walsh basis functions. In the receiver, the received signal is matched to each extended basis-function which is the union of the transmitter basis-functions and their delayed replicas, and the matched-filtered chip samples are combined together after individual channel compensation. The conventional DS/CDMA system using the maximal ratio combining. In addition, it effectively resolves the high PAR and high sensitivity to frequency offset problems which are critical in multi-carrier systems.

• Animal Bioscience
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• v.36 no.9
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• pp.1305-1313
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• 2023

Synthetic antioxidants have shown adverse effects on consumers. The review, thus, aims to assess the effect of marinating broiler meat with plant leaves-derived antioxidants potential for improving shelf-life and human health. Broiler meat loss and waste due to spoilage is more than three million kg annually, thus, extending shelf-life by reducing initial microbial load and autoxidation is essential. Adding various antioxidants would reduce oxidation of protein and fatty acids improving nutritional shelf-life through synergic interactions. Antioxidant synergetic effects also improves reduction in microbiota proliferation leading to the delayed development of off flavours and deterioration of meat colour. To reduce initial microbial load and autoxidation effects, the inclusion of polyphenols and antioxidants from varying sources by mixing various antioxidants would lead to improved synergic effects.