• Title/Summary/Keyword: passive mechanism

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Review of Acute Traumatic Closed Mallet Finger Injuries in Adults

  • Botero, Santiago Salazar;Diaz, Juan Jose Hidalgo;Benaida, Anissa;Collon, Sylvie;Facca, Sybille;Liverneaux, Philippe Andre
    • Archives of Plastic Surgery
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    • v.43 no.2
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    • pp.134-144
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    • 2016
  • In adults, mallet finger is a traumatic zone I lesion of the extensor tendon with either tendon rupture or bony avulsion at the base of the distal phalanx. High-energy mechanisms of injury generally occur in young men, whereas lower energy mechanisms are observed in elderly women. The mechanism of injury is an axial load applied to a straight digit tip, which is then followed by passive extreme distal interphalangeal joint (DIPJ) hyperextension or hyperflexion. Mallet finger is diagnosed clinically, but an X-ray should always be performed. Tubiana's classification takes into account the size of the bony articular fragment and DIPJ subluxation. We propose to stage subluxated fractures as stage III if the subluxation is reducible with a splint and as stage IV if not. Left untreated, mallet finger becomes chronic and leads to a swan-neck deformity and DIPJ osteoarthritis. The goal of treatment is to restore active DIPJ extension. The results of a six- to eight-week conservative course of treatment with a DIPJ splint in slight hyperextension for tendon lesions or straight for bony avulsions depends on patient compliance. Surgical treatments vary in terms of the approach, the reduction technique, and the means of fixation. The risks involved are stiffness, septic arthritis, and osteoarthritis. Given the lack of consensus regarding indications for treatment, we propose to treat all cases of mallet finger with a dorsal glued splint except for stage IV mallet finger, which we treat with extra-articular pinning.

An alternative method to reduce anaphylaxis by moxibustion

  • Jeong, Hyun-Ja;Nam, Sun-Young;Lee, Byong-Joo;Kim, Min-Gi;Kim, Jeong-Hwa;Kim, Hyung-Min
    • CELLMED
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    • v.4 no.2
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    • pp.12.1-12.12
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    • 2014
  • Epinephrine is a critical drug for patients at risk for anaphylaxis. Here, we suggest moxibustion as an alternative method to reduce anaphylaxis. Moxibustion was applied to the Shimen (CV5) acupoint and found to attenuate compound 48/80-induced mortality. Capsazepine, a transient receptor potential vanilloid (TRPV) 1 antagonist, significantly improved overall survival rates compared to groups treated with moxibustion or 2-aminoethoxydiphenyl borate (an activator of TRPV1, 2, and 3). Probenecid (a TRPV2 agonist) also increased survival rate and reduced histamine levels. Survival rates increased by moxibustion and probenecid were completely inhibited by ruthenium red (a TRPV2 and 3 antagonist) and gadolinium chloride (general TRPV antagonist), respectively. Passive cutaneous anaphylaxis and ear swelling were significantly reduced by moxibustion and probenecid (p < 0.05). In cardiomyocytes, TRPV2 was over-expressed by compound 48/80 and histamine but this increased TRPV2 expression decreased to baseline with moxibustion and probenecid treatment. In addition, intracellular calcium levels increased by compound 48/80 were reduced by probenecid. Overall, these findings suggest that the reduction of anaphylaxis caused by moxibustion could represent a new mechanism of moxibustion related to the regulation of TRPV2 activation and promotion of epinephrine secretion.

Lactobacillus plantarum 299v Surface-Bound GAPDH: A New Insight Into Enzyme Cell Walls Location

  • Saad, N.;Urdaci, M.;Vignoles, C.;Chaignepain, S.;Tallon, R.;Schmitter, J.M.;Bressollier, P.
    • Journal of Microbiology and Biotechnology
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    • v.19 no.12
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    • pp.1635-1643
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    • 2009
  • The aim of this study was to provide new insight into the mechanism whereby the housekeeping enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) locates to cell walls of Lactobacillus plantarum 299v. After purification, cytosolic and cell wall GAPDH (cw-GAPDH) forms were characterized and shown to be identical homotetrameric active enzymes. GAPDH concentration on cell walls was growth-time dependent. Free GAPDH was not observed on the culture supernatant at any time during growth, and provoked cell lysis was not concomitant with any reassociation of GAPDH onto the cell surface. Hence, with the possibility of cw-GAPDH resulting from autolysis being unlikely, entrapment of intracellular GAPDH on the cell wall after a passive efflux through altered plasma membrane was investigated. Flow cytometry was used to assess L. plantarum 299v membrane permeabilization after labeling with propidium iodide (PI). By combining PI uptake and cw-GAPDH activity measurements, we demonstrate here that the increase in cw-GAPDH concentration from the early exponential phase to the late stationary phase is closely related to an increase in plasma membrane permeability during growth. Moreover, we observed that increases in both plasma membrane permeability and cw-GAPDH activity were delayed when glucose was added during L. plantarum 299v growth. Using a double labeling of L. plantarum 299v cells with anti-GAPDH antibodies and propidium iodide, we established unambiguously that cells with impaired membrane manifest five times more cw-GAPDH than unaltered cells. Our results show that plasma membrane permeability appears to be closely related to the efflux of GAPDH on the bacterial cell surface, offering new insight into the understanding of the cell wall location of this enzyme.

Characteristics of electrodes using V-Ti based hydrogen storage alloys (V-Ti계 수소저장합금의 전극특성)

  • 김주완;이성만;백홍구
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.7 no.2
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    • pp.284-291
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    • 1997
  • The electrode characteristics of two kinds of metal hydride electrodes using V-Ti (V-rich) based alloy were studied, in which one electrode was prepared by sintering the mixture of V-Ti alloy and Ni powders by a rapid thermal annealing technique and the other one was prepared using V-Ti-Ni ternary alloy, The discharge capacities of all electrodes during the charge-discharge cycling were completely deteriorated within 10 cycles. It appeared that the deterioration of the electrodes was caused by the dissolution of V in the near-surface region into the electrolyte and the formation of $TiO_2$ layer on the alloy particle surface. This degradation mechanism was supported by the facts that V is main hydride forming element and $TiO_2$ has very low electrical conductivity and hydrogen diffusivity.

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Analytical Investigation on the Deflection Characteristics of Steel Piles in Bridge Abutment for Aspect Ratio and Ground Properties (형상비 및 지반특성에 따른 교대 강관파일의 변위특성에 대한 해석적 연구)

  • Jang, Gab-Chul;Chang, Kyong-Ho;Han, Jung-Geun;Lee, Yang-Koo;Kim, Jong-Ryeol
    • Journal of Korean Association for Spatial Structures
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    • v.7 no.4
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    • pp.73-78
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    • 2007
  • The surrounding ground was much transformed by the lateral movement on the soft ground, and consequently the stake basis was damaged. In this case the installed stake is ratted the passive stake, and is actively being researched. When the unevenly distributed load was applied on the stake, and thus the lateral ground pressure was operated, and then the lateral movement was occurred, and consequently the structure is influenced. However, prediction and mechanism for the relationship of piles and abutment deformation is not sufficient. In this paper, coupled three-dimensional finite element analysis, which can be described solid, plate and frame elements at the same time, is developed by the authors. The lateral movement of bridge abutment for the aspect ratio of steel piles on soft clay is clarified by using developed numerical analysis.

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Effect of Leonurus japonicus Houtt. on Scopolamine-induced Memory Impairment in Mice (Scopolamine 유발 기억 손상 마우스에서 익모초의 효과)

  • Lee, Jihye;Kim, Hye-Jeong;Jang, Gwi Yeong;Seo, Kyung Hye;Kim, Mi Ryeo;Choi, Yun Hee;Jung, Ji Wook
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.34 no.2
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    • pp.81-87
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    • 2020
  • Cognitive impairment is symptoms of dementia, a degenerative brain disease that is drawing attention in a rapidly aging society. This study was conducted to investigate the improvement of cognitive function of Leonurus japonicus on scopolamine-induced memory impairment in mice and the effect and mechanism of memory recovery. In vivo studies were conducted on mice orally pretreated with L. japonicus in doses of 50, 100 and 200 mg/kg (p.o.) and scopolamine (1 mg/kg, i.p.) were injected 30 min before the behavioral task. Antioxidant activity was assessed by 2,2-diphenyl-1-picryl hydrazyl (DPPH) assay and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay, and acetylcholinesterase (AChE) inhibition activity evaluated by Ellman's method. In behavior studies showed that L. japonicus has an improved the memory of scopolamine-treated mice in Y-maze, passive avoidance and Morris water maze test. In addition, L. japonicus was also exerted free radical scavenging activity and inhibited acetyl cholinesterase activity. These results suggest that L. japonicus improves short-term and long-term memory in scopolamine-induced memory decline model and prevents scopolamine-induced memory impairments through in reduced oxidative stress and acetyl cholinesterase inhibition effect. Thus, L. japonicus is related to functional medicinal materials for prevention and treatment of human dementia patients.

Imperatorin is Transported through Blood-Brain Barrier by Carrier-Mediated Transporters

  • Tun, Temdara;Kang, Young-Sook
    • Biomolecules & Therapeutics
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    • v.25 no.4
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    • pp.441-451
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    • 2017
  • Imperatorin, a major bioactive furanocoumarin with multifunctions, can be used for treating neurodegenerative diseases. In this study, we investigated the characteristics of imperatorin transport in the brain. Experiments of the present study were designed to study imperatorin transport across the blood-brain barrier both in vivo and in vitro. In vivo study was performed in rats using single intravenous injection and in situ carotid artery perfusion technique. Conditionally immortalized rat brain capillary endothelial cells were as an in vitro model of blood-brain barrier to examine the transport mechanism of imperatorin. Brain distribution volume of imperatorin was about 6 fold greater than that of sucrose, suggesting that the transport of imperatorin was through the blood-brain barrier in physiological state. Both in vivo and in vitro imperatorin transport studies demonstrated that imperatorin could be transported in a concentration-dependent manner with high affinity. Imperatorin uptake was dependent on proton gradient in an opposite direction. It was significantly reduced by pretreatment with sodium azide. However, its uptake was not inhibited by replacing extracellular sodium with potassium or N-methylglucamine. The uptake of imperatorin was inhibited by various cationic compounds, but not inhibited by TEA, choline and organic anion substances. Transfection of plasma membrane monoamine transporter, organic cation transporter 2 and organic cation/carnitine transporter 2/1 siRNA failed to alter imperatorin transport in brain capillary endothelial cells. Especially, tramadol, clonidine and pyrilamine inhibited the uptake of [$^3H$]imperatorin competitively. Therefore, imperatorin is actively transported from blood to brain across the blood-brain barrier by passive and carrier-mediated transporter.

Investigating the supporting effect of rock bolts in varying anchoring methods in a tunnel

  • Wang, Hongtao;Li, Shucai;Wang, Qi;Wang, Dechao;Li, Weiteng;Liu, Ping;Li, Xiaojing;Chen, Yunjuan
    • Geomechanics and Engineering
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    • v.19 no.6
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    • pp.485-498
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    • 2019
  • Pre-tensioned rock bolts can be classified into fully anchored, lengthening anchored and point anchored bolts based on the bond length of the resin or cement mortar inside the borehole. Bolts in varying anchoring methods may significantly affect the supporting effect of surrounding rock around a tunnel. However, thus far, the theoretical basis of selecting a proper anchoring method has not been thoroughly investigated. Based on this problem, 16 schemes were designed while incorporating the effects of anchoring length, pretension, bolt length, and spacing, and a systematic numerical experiment was performed in this paper. The distribution characteristics of the stress field in the surrounding rock, which corresponded to various anchoring scenarios, were obtained. Furthermore, an analytical approach for computing the active and passive strengthening index of the anchored surrounding rock is presented. A new fully anchoring method with pretension and matching technology are also provided. Then, an isolated loading model of the anchored surrounding rock was constructed. The physical simulation test for the bearing capacity of the model was performed with three schemes. Finally, the strengthening mechanism of varying anchoring methods was validated. The research findings in this paper may provide theoretical guidelines for the design and construction of bolting support in tunnels.

Evolution of Vertical Integration in the Korea Broiler Industry (한국육계산업의 수직통합(계열화) 전개상황)

  • 박영인
    • Korean Journal of Poultry Science
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    • v.18 no.1
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    • pp.57-66
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    • 1991
  • The broiler industry in Korea has been gradually changing its structure of independent operation into integrated and coordinated production and marketing system. It was in 1960s when the broiler industry first tried the integrated effort, but never succeeded as it was expected since due mainly to growers' attitudes favorable for traditional operation and agribusiness' passive response on structure change. Until mid 1980s, however, a bit of partially integrated system had been evolved by several factor suppliers. Recent years have furthered its progress toward completely integrated pattern, the ultimate goal of broiler integration. It is true that the external factors including the GATT Negotiations through the Uruguay Round stimulated the people involved in the industry to find the way of making it competitive to survive in the open, liberalized world economic system rapidly emerging through the process of globalization. Once the industry realized the necessity of reducing the cost of production and improving the quality of it, the conclusion tended to come to the point of an entire structural alteration by means of integration rather than an improvement of a certain segment such as marketing. It is very obvious. therefore. that the movement toward the complete integration will speed up in a coming few years under the leadership of not only entrepreneurs but also producers group. According to a report. there were three almost complete integrators and thirteen partial integrators as of December, 1990, all of which eagerly directed toward the completely integrated system in due course . Among others as an advantage of integrated structure. the cost saving must be pointed out as the greatest one In a survey, it was estimated that the cost of dressed and ready-to-eat chicken could be lowered by 31.8 percent and 41.5 percent, respectively, over that to be under the independent, non-integrated system. As long as everybody concerned about the future of the industry in the open market mechanism realizes the importance of the structure change through an integration, the broiler sector of Korean agriculture shall be moving toward the direction of vertically and completely integrated structure in order to make it competitive, even to export, hopefully before 1995 or by the end of this century in any case.

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Therapeutic Potential of Jeongjihwan for the Prevention and Treatment of Amnesia (정지환(定志丸)의 기억 및 인지기능 향상에 대한 효능 연구)

  • Jung, Tae-Young;Jeong, Won-Choon;Park, Jong-Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.25 no.1
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    • pp.37-47
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    • 2011
  • This study was aimed to investigate the memory enhancing effect of Jeongjihwan against scopolamine-induced amnesia in C57BL/6 mice. To determine the effect of Jeongjihwan on the memory and cognitive function, we have injected scopolamine (1 mg/kg, i.p.) into C57BL/6 mice 30 min before beginning of behavior tests. We have conducted Y-maze, Morris water-maze, passive avoidance and fear conditioning tests to compare learning and memory functions. Scopolamine-induced behavior changes of memory impairment were significantly restored by oral administration of Jeongjihwan (100 or 200 mg/kg/day). To elucidate the molecular mechanism underlying the memory enhancing effect of Jeongjihwan, we have examined the antioxidant defense system and neurotrophic factors. Jeongjihwan treatment attenuated intracellular accumulation of reactive oxygen species and up-regulated mRNA and protein expression of antioxidant enzymes as assessed by RT-PCR and western blot analysis, respectively. Jeongjihwan also increased protein levels of brain-derived neurotrophic factor (BDNF) compared with those in the scopolamine-treated group. Furthermore, as an upstream regulator, the activation of cAMP response element-binding protein (CREB) via phosphorylation was assessed by Western blot analysis. Jeongjihwan elevated the phosphorylation of CREB (p-CREB), which seemed to be mediated partly by extracellular signal-regulated kinase1/2 (ERK1/2) and protein kinase B/Akt. These findings suggest that Jeongjihwan may have preventive and therapeutic potential in the management of amnesia.