• 제목/요약/키워드: Delayed potential

검색결과 291건 처리시간 0.034초

흰쥐의 전층피부상처 동물모델에서 소풍산(消風散)이 VEGF 및 TGF-β1발현에 미치는 영향 (Sopung-san Extract Enhances healing potential on Full-thickness Skin Wound in Rats: Role of VEGF and TGF-β1)

  • 김범회
    • 대한한의학방제학회지
    • /
    • 제25권2호
    • /
    • pp.123-134
    • /
    • 2017
  • Wounds are commonly created during almost every kind of surgery, trauma and skin diseases. Delayed wound healing affects a plenty of patients and requires prolonged treatments that seriously reduce the quality of life for patients. Skin damage involving large areas or great severity can lead to disability or even death. Wound healing involves a complicated series of actions, of various tissues and cell lineages, concerning inflammation, migration, proliferation, reepithelialization, and remodeling. Sopung-san is reported to have anti-inflammatory effect and has been used for various skin diseases such as allergic dermatitis and atopic dermatitis. In this study, the hypothesis that oral treatment with Sopung-san could enhances healing potential on rat full thickness skin wounds was tested. Twenty young male Sprague-Dawley rats were used for the studies. A full-thickness skin wound was made on the dorsal skin of the rats. Either Sopung-san water extract (SPS) or saline (Control) was orally administrated every day. The wound area was measured and the percentages of wound contraction, wound healed and wound epithelization were calculated. Wound tissue samples were excised following injection for histopathological and immunohistological examination. Wound area in rats of SPS group significantly was decreased compared to Control. SPS group showed significant promotion of wound healing compared to Cotrol group in the percentages of wound contraction, wound healed and wound epithelization. Histopathological examination revealed that SPS induces neo-vascularization potential in wound healing process. SPS treatment in rats significantly accelerated cutaneous wound healing in the neo-vascularization process by increasing VEGF and $TGF-{\beta}1$ synthesis. The results suggest that Sopung-san affects key cellular processes responsible for wound repair and point to a unique potential for this molecule in the therapy of skin wounds, particularly as an angiogenic agent.

Biologic response of local hemostatic agents used in endodontic microsurgery

  • Jang, Youngjune;Kim, Hyeon;Roh, Byoung-Duck;Kim, Euiseong
    • Restorative Dentistry and Endodontics
    • /
    • 제39권2호
    • /
    • pp.79-88
    • /
    • 2014
  • Appropriate use of local hemostatic agent is one of the important factors on the prognosis of endodontic microsurgery. However, most investigations to date focus on the hemostatic efficacy of the agents, whereas their biologic characteristics have not received enough attention. The purpose of this paper was to review the biologic response of local hemostatic agents, and to provide clinical guidelines on their use during endodontic microsurgery. Electronic database (PUBMED) was screened to search related studies from 1980 to 2013, and 8 clinical studies and 18 animal studies were identified. Among the materials used in these studies, most widely-investigated and used materials, epinephrine, ferric sulfate (FS) and calcium sulfate (CS), were thoroughly discussed. Influence of these materials on local tissue and systemic condition, such as inflammatory and foreign body reaction, local ischemia, dyspigmentation, delayed or enhanced bone and soft tissue healing, and potential cardiovascular complications were assessed. Additionally, biological property of their carrier materials, cotton pellet and absorbable collagen, were also discussed. Clinicians should be aware of the biologic properties of local hemostatic agents and their carrier materials, and should pay attention to the potential complications when using them in endodontic microsurgery.

Block of hERG $K^+$ Channel by Classic Histamine $H_1$ Receptor Antagonist Chlorpheniramine

  • Hong, Hee-Kyung;Jo, Su-Hyun
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제13권3호
    • /
    • pp.215-220
    • /
    • 2009
  • Chlorpheniramine is a potent first-generation histamine $H_1$ receptor antagonist that can increase action potential duration and induce QT prolongation in several animal models. Since block of cardiac human ether-a-go-go-related gene (hERG) channels is one of leading causes of acquired long QT syndrome, we investigated the acute effects of chlorpheniramine on hERG channels to determine the electrophysiological basis for its proarrhythmic potential. We examined the effects of chlorpheniramine on the hERG channels expressed in Xenopus oocytes using two-microelectrode voltage-clamp techniques. Chlorpheniramine induced a concentration-dependent decrease of the current amplitude at the end of the voltage steps and hERG tail currents. The $IC_{50}$ of chlorpheniramine-dependent hERG block in Xenopus oocytes decreased progressively relative to the degree of depolarization. Chlorpheniramine affected the channels in the activated and inactivated states but not in the closed states. The S6 domain mutations Y652A and F656A partially attenuated (Y652A) or abolished (F656A) the hERG current block. These results suggest that the $H_1$ antihistamine, chlorpheniramine is a blocker of the hERG channels, providing a molecular mechanism for the drug-induced arrhythmogenic side effects.

Miller Fisher 증후군1예에서 일련의 신경생리학적 소견 (Serial Electrophysiological Studies in Miller Fisher Syndrome)

  • 전동철;박춘강;이규용;이영주;김주한
    • Annals of Clinical Neurophysiology
    • /
    • 제3권2호
    • /
    • pp.156-159
    • /
    • 2001
  • Miller Fisher syndrome(MFS) has been the focus of conflicting opinions regarding the peripheral versus the central nature of the site of major neural injury. We present our electrophysiological findings in one case of MFS to help clarify the pattern of peripheral nerve injury in this syndrome. A 45-year-old man visited our hospital due to sudden diplopia. Initial examination revealed internuclear opthalmoplegia. The next day, his symptoms rapidly aggravated to complete external ophthalmoplegia, ataxia, and areflexia with hand and foot numbness. Serial electrophysiological studies were performed. The results of brainstem evoked potential(BAEP) and blink reflex were normal in the serial studies. Motor and sensory nerve conduction study(NCS) were normal findings in second hospital day, but ulnar sensory nerve shows no sensory nerve action potential(SNAP) and sural sensory conduction velocity was delayed in 7th hospital day. Our patient's clinical presentation began to improve on 15th hospital day, and his electrophysiologic study showed improvement on 29th hospital day. We believe that all the manifestations of MFS can be explained by the involvement of peripheral nerves without brainstem or cerebellar lesion with the serial electrophysiological studies.

  • PDF

Oleanolic Acid Provides Neuroprotection against Ischemic Stroke through the Inhibition of Microglial Activation and NLRP3 Inflammasome Activation

  • Sapkota, Arjun;Choi, Ji Woong
    • Biomolecules & Therapeutics
    • /
    • 제30권1호
    • /
    • pp.55-63
    • /
    • 2022
  • Oleanolic acid (OA), a natural pentacyclic triterpenoid, has been reported to exert protective effects against several neurological diseases through its anti-oxidative and anti-inflammatory activities. The goal of the present study was to evaluate the therapeutic potential of OA against acute and chronic brain injuries after ischemic stroke using a mouse model of transient middle cerebral artery occlusion (tMCAO, MCAO/reperfusion). OA administration immediately after reperfusion significantly attenuated acute brain injuries including brain infarction, functional neurological deficits, and neuronal apoptosis. Moreover, delayed administration of OA (at 3 h after reperfusion) attenuated brain infarction and improved functional neurological deficits during the acute phase. Such neuroprotective effects were associated with attenuation of microglial activation and lipid peroxidation in the injured brain after the tMCAO challenge. OA also attenuated NLRP3 inflammasome activation in activated microglia during the acute phase. In addition, daily administration of OA for 7 days starting from either immediately after reperfusion or 1 day after reperfusion significantly improved functional neurological deficits and attenuated brain tissue loss up to 21 days after the tMCAO challenge; these findings supported therapeutic effects of OA against ischemic stroke-induced chronic brain injury. Together, these findings showed that OA exerted neuroprotective effects against both acute and chronic brain injuries after tMCAO challenge, suggesting that OA is a potential therapeutic agent to treat ischemic stroke.

Effect of Coffee Grounds on Mechanical Behavior of Poly Propylene Composites

  • Vinitsa Chanthavong;M. N. Prabhakar;Dong-Woo Lee;Jung-Il Song
    • Composites Research
    • /
    • 제36권4호
    • /
    • pp.264-269
    • /
    • 2023
  • Spent coffee grounds (SCG) are a ubiquitous byproduct of coffee consumption, representing a significant waste management challenge, as well as an untapped resource for economic development and sustainability. Improper disposal of SCG can result in environmental problems such as methane emissions and leachate production. This study aims to investigate the physicochemical properties of SCG and their potential as a reinforcement material in polypropylene (PP) to fabricate an eco-friendly composite via extrusion and injection molding, with SCG filler ratios ranging from 5-20%. To evaluate the effect of SCG on the morphological and mechanical properties of the bio- composite, thermogravimetric analysis, SEM, tensile, flexural, and impact tests were conducted. The results demonstrated that the addition of SCG lead to a slight increase in brittleness of the composite but did not significantly affect its mechanical properties. Impressively, the presence of a significant organic component in SCG contributed to the enhanced thermal performance of PP/SCG composites. This improvement was evident in terms of increased thermal stability, delayed onset of degradation, and higher maximum degradation temperature as compared to pure PP. These findings suggest that SCG has potential as a filler material for PP composites, with the ability to enhance the material's properties without compromising overall performance.

Ginseng and ginsenosides on cardiovascular and pulmonary diseases; Pharmacological potentials for the coronavirus (COVID-19)

  • Ajay Vijayakumar;Jong-Hoon Kim
    • Journal of Ginseng Research
    • /
    • 제48권2호
    • /
    • pp.113-121
    • /
    • 2024
  • Since its outbreak in late 2019, the Coronavirus disease 2019 (COVID-19) pandemic has profoundly caused global morbidity and deaths. The COVID-19 pandemic caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has major complications in cardiovascular and pulmonary system. The increased rate of mortality is due to delayed detection of certain biomarkers that are crucial in the development of disease. Furthermore, certain proteins and enzymes in cellular signaling pathways play an important role in replication of SARS-CoV-2. Most cases are mild to moderate symptoms, however severe cases of COVID-19 leads to death. Detecting the level of biomarkers such as C-reactive protein, cardiac troponin, creatine kinase, creatine kinaseMB, procalcitonin and Matrix metalloproteinases helps in early detection of the severity of disease. Similarly, through downregulating Renin-angiotensin system, interleukin, Mitogen-activated protein kinases and Phosphoinositide 3-kinases pathways, COVID-19 can be effectively controlled and mortality could be prevented. Ginseng and ginsenosides possess therapeutic potential in cardiac and pulmonary complications, there are several studies performed in which they have suppressed these biomarkers and downregulated the pathways, thereby inhibiting the further spread of disease. Supplementation with ginseng or ginsenoside could act on multiple pathways to reduce the level of biomarkers significantly and alleviate cardiac and pulmonary damage. Therefore, this review summarizes the potential of ginseng extract and ginsenosides in controlling the cardiovascular and pulmonary diseases by COVID-19.

평년 기후자료를 활용한 국내 벼 안전출수 한계기의 시공간적 변화 평가 (Spatiotemporal Assessment of the Late Marginal Heading Date of Rice using Climate Normal Data in Korea)

  • 이동준;김준환;김광수
    • 한국농림기상학회지
    • /
    • 제16권4호
    • /
    • pp.316-326
    • /
    • 2014
  • 출수한계기의 설정을 통해 이앙한계기 및 파종한계기 추정이 가능하며, 이는 이모작 가능 지대를 파악할 수 있게 하여 기후변화에 따른 작부체계 설정에 도움을 줄 수 있다. 본 연구에서는 과거평년인 1971년부터 2000년까지의 기상자료와 현재평년인 1981년부터 2010년까지의 기상자료를 이용하여 51개의 관측지점에서의 출수한계기를 설정하였으며 최대 잠재적 수량 개념인 기후등숙량을 이용하여 생산성을 검정하였다. 출수 후 40일 동안 평균기온의 누적온도를 이용하여 계산되는 출수한계기를 설정하기 위해 $760^{\circ}C$, $800^{\circ}C$, $840^{\circ}C$$880^{\circ}C$를 기준온도로 사용하였다. 또한, 기후등숙량은 출수 후 40일 간의 평균온도 및 일조시간을 이용하였다. 출수한계기에서 출수를 하였을 경우 일반적인 벼 재배시기에 비해 수량이 얼마나 감소하는지를 분석하기 위해 출수한계기에서의 기후등숙량을 기후등숙량의 최대값으로 나눠 그 비율값인 $CYP/CYP_{max}$을 구하였다. 출수한계기 분석 결과 과거평년에 비해 현재평년에서 출수한계기가 앞당겨지거나 변화가 없는 관측지점도 있었으나 대부분의 지점에서 출수한 계기가 늦추어졌으며 기준온도별로 그 변화가 상이하였다. $CYP/CYP_{max}$값은 모든 조건에서 81.8%이상의 값을 보였으며 대부분의 조건에서 90%이상의 값을 보였다. 따라서, 출수한계기까지 출수를 늦추더라도 기후적인 측면에서는 수량에 대한 손실이 크지 않을 것으로 사료된다. 출수한계기가 늦추어진 경우, 이는 이앙한계기 역시 늦추어질 것을 나타내며, 결국, 기후변화 조건에서 이모작 가능 지역이 증가할 가능성이 높을 것으로 사료되었다. 본 연구는 출수 후 40일간의 평균온도와 일조만을 대상으로 분석하여, 급작스러운 기온저하나 개화기 고온장해 등과 같은 기상장해 등은 고려하지 않았다. 따라서, 등숙기 기간동안의 특이적인 기상조건을 고려하고 보다 생물리학적인 수량예측을 위해 작물 모델을 사용한 연구가 추후에 수행되어야 할 것으로 사료된다. 또한, 이러한 방법을 사용하여 우리나라뿐만 아니라 동아시아 지역에서 미래기후조건에서의 재배한계기에 대한 분석를 통해 지역적인 기후변화적응 대책에 대한 연구가 필요할 것이다.

Implementing Balanced Scorecard with System Dynamics Approach

  • Yoon, Joseph Y. K.
    • 한국경영과학회:학술대회논문집
    • /
    • 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
    • /
    • pp.330-336
    • /
    • 2000
  • This paper discusses the potential of system dynamics modelling to support balanced scorecard. The balanced scorecard is a conceptual framework for translating an organisation's strategy into a set of performance indicators. These performance indicators are distributed across the 'classic'model's four perspective: Customers, Internal Business Processes, Financial, and Learning and Growth. This balanced scorecard, whilst having significant strength, suffers from the limitation of all performance indicator systems, namely that the interrelationships between indicators are overlooked and there is no way of taking into account the impact of delayed feedback which flows from introduction of new policy and legislative changes. System Dynamics is a methodology for understanding complex problems where there is dynamic behaviour and where feedback impacts significantly on system outcomes. System dynamics provides a rigorous basis for qualitative testing of the effects of performance indicators in complex environments such as health or social security. This can be supplemented with quantitative system dynamics simulation tools that further test the validity of indicators and the business rules implicit in them. System dynamics modelling has an important role to play in extending feedback cycle in performance measurements to a full systems approach.

  • PDF

Plasmid- and Chromosome-Mediated Assimilation of Phenol and Cyanide in Pseudomonas sp. Strain PhCN

  • El-Deeb Bahig A.
    • Journal of Microbiology and Biotechnology
    • /
    • 제16권7호
    • /
    • pp.1068-1077
    • /
    • 2006
  • Pseudomonas sp. PhCN strain, which has the potential to utilize phenol and cyanide as a sole carbon and nitrogen source, was isolated. A comparison of the effect of cyanide on phenol degradation and vice versa by strain PhCN showed that the degradation time was significantly delayed by an increase in either phenol or cyanide concentration, and the greatest activities were obtained in basal medium containing a low concentration of cyanide and phenol. This strain contained two plasmids of approximately 120 kb (pPhCN-1) and 110 kb (pPhCN-2). Plasmid curing experiments produced a plasmid-free strain as well as strains containing either the 120- or the 110 kb plasmid. The strains were tested for their ability to utilize phenol and KCN. The results demonstrated that the ability to utilize phenol was encoded by the 120 kb plasmid, whereas the ability to utilize cyanide appeared to be encoded by the chromosome.