• Title/Summary/Keyword: $A{\delta}$ and C fiber

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A Study of Current Perception Threshold of Trigeminal Nerve after Tooth Implantation (치아임플란트 시술 후 삼차신경에서의 전류인지역치에 대한 연구)

  • Lim, Hyun-Dae;Lee, Jung-Hyun;Lee, You-Mee
    • Journal of Oral Medicine and Pain
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    • v.32 no.2
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    • pp.187-200
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    • 2007
  • This study attempted to contribute to the clinical application of implant operation by making a quantitative nerve examination using a neurometer for the evaluation of sensory disturbances that could be incurred after the implantation in the dental clinics, and it intended to establish an objective guideline in the evaluation of sensory nerve after the operation of implant. An inspection was performed with the frequencies of 2000Hz, 250 Hz and 5 Hz before and after the operations of tooth implant using $Neurometer^{(R)}$ CPT/C (Neurotron, Inc. Baltimore, Maryland, USA) for 44 patients who had performed an implant operation among the patients coming to Daejeon Sun Dental Hospital in 2006 and 30 people for control group. The measuring sites were maxillary nerve ending and mandibular nerve ending of trigeminal nerve according to the implant operating regions. The current perception threshold (CPT) by each nerve fiber was specifically responded under the electric stimulation of 2000 Hz in case of $A{\beta}$ fiber and of 250 Hz in case of $A{\delta}$ fiber and of 5Hz in case of C fiber. The CPT test could be performed to assess the damages of peripheral nerve in the trigeminal nerve area and it stimulated selective nerve fibers by generating the electricity of specific frequency in the peripheral nerve area. The nerve fibers with varied thickness were responsive selectively to the electric stimulation with different frequencies; accordingly, they applied the electric stimulation with different frequencies and the reaction threshold of $A{\beta},\;A{\delta}$ and C fibers selectively responsive to each electric current could be individually evaluated. In the assessment through the CPT, the increase and decrease of the CPT could be measured so that sensory disturbances such as hyperaesthesia or hypoaesthesia could be diagnosed. This study could obtain the following results after the assessment of the CPT before and after the implant operation. 1. In the assessment before and after the implant operation, the CPT in the frequencies of 2000 Hz, 250 Hz, 5 Hz for maxillary branch increased on the whole after the operation and the CPT for mandibular branch in the $A{\beta}$-fiber(2000 Hz) and C-fiber(5 Hz )after the operation increased statistically significantly. 2. For the groups of patients with medically compromised or its subsequent medicinal prescription, there were no significant differences before and after the implant operation and for the control groups, significantly high CPT was shown after the implant operation in the left $A{\beta}$-fiber(2000 Hz) and C-fiber(5 Hz). 3. In the comparison of the measured value of the CPT before the operation between the control group and the implant operation group, the latter group had a significantly high measured value of the CPT in the right $A{\beta}$-fiber(2000 Hz) and C-fiber(5 Hz) and there were significant differences in $A{\beta}$-fiber(2000 Hz) in the CPT assessment after the implant operation for the control group. 4. Male participants had higher CPT than female counterparts; however, there were no statistic significances. In the CPT evaluation before and after implant operation, there were no statistical differences in the male group while the right C-fiber(5 Hz) and left $A{\beta}$-fiber(2000Hz) were significantly high in the female group. 5. In the comparison between the group who complain sensory disturbance and the other group, the CPT increased on the whole in the former group, but there were no statistical significances. In the groups, whom there was an increase in VAS, the CPT after the implant operation in the right C-fiber(5 Hz) increased significantly; meanwhile, in case that the VAS mark was '0' before and after the operation, the CPT after the operation in the left $A{\beta}$-fiber(2000 Hz) increased significantly. This study suggested that the CPT measurements using $Neurometer^{(R)}$ CPT/C, provide useful information of objective and quantitative sensory disturbances for tooth implantation.

Comparison of Cold Pack and Capsaicin Application in Temporomandibular Disorder Treatment (측두하악장애 치료에 있어 냉찜질과 capsaicin적용에 관한 비교)

  • Lim, Hyun-Dae;Lee, You-Mee
    • Journal of Oral Medicine and Pain
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    • v.32 no.2
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    • pp.219-225
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    • 2007
  • This investigation was carried out to evaluate the effect of pain control temporomandibular disorders with clinical application of capsaicin cream. 20 healthy subjects without systemic diseases were measured in current perception threshold and pain tolerance threshold with $Neurometer^{(R)}$ CPT/C (Neurotron, Inc. Baltimore, Maryland, USA) after cold pack, 0.025% capsaicin and 0.075% capsaicin cream application. The obtained results were as follows : 1. The current perception threshold of C-fiber was significantly higher to the baseline on. There were significantly increased in C- fiber current perception threshold of 0.025% capsaicin cream and 0.075% capsaicin cream application comparison to cold pack. 2. There was significantly increased in pain tolerance threshold of cold pack and 0.075% capsaicin application comparison to one of baseline as $A{\beta}$-fiber, There was significantly higher after cold pack and 0.025% capsaicin cream application than baseline as $A{\delta}$-fiber. In C-fiber case, 0.025% capsaicin application's was significantly increased than baseline one. 3.There were significantly higher C-fiber of 0.075% capsaicin application than baseline in visual analogue scale marking pain level of pain tolerance threshold.

The Effects of Annealing Temperature on The Physical Properties and Fine Structure of Poly(trimethylene terephthalate)(PTT) Fibers (열처리 온도가 Poly(trimethylene terephthalate)(PTT) 섬유의 역학적 성질과 미세구조에 미치는 효과)

  • Jeong, Kyung Hui;Lee, Eon Pil;Lee, Jae Ho
    • Fashion & Textile Research Journal
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    • v.15 no.6
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    • pp.985-992
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    • 2013
  • Polytrimethylene terephthalate(PTT) offers several advantageous properties such as good tensile strength, uniformity, stiffness, toughness, UV stability, resilience, stain resistance, outstanding elastic recovery, and dyeability. The effects of annealing temperature on physical properties and the structure of PTT filaments and yarn were investigated by measuring wide-angle X-ray diffraction (WAXD), density, optical birefringence, dynamic visco elasticity, and tensile testing. The intensity of maximum tan ${\delta}$ decreased and the temperature of maximum tan ${\delta}$ shifted to a higher temperature as the annealing temperature of filaments increased; however, it shifted to a lower temperature when the annealing temperature exceeded $130^{\circ}C$. In addition, crystallinity, density and D-spacing of (010) crystal face increased as the annealing temperature increased. Optical birefringence and specific stress were almost constant up to $100^{\circ}C$ and then decreased above $130^{\circ}C$. The shrinkage of PTT filament is 0 in boiling water when annealed above $130^{\circ}C$; consequently, the use of annealed fiber above $130^{\circ}C$ can remove thermal instability when dyeing PTT fiber. In the case of yarns, the thermal stability and physical properties of yarns showed the best effect when the ply number is less than 5, twist number is less than 400tpm, and the annealing time is 20minutes.

Effect of Acetophenone on the Rate of Wool Dyeing (아세토페논이 양모의 염색속도에 미치는 영향)

  • Dho, Seong-Kook
    • Fashion & Textile Research Journal
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    • v.10 no.3
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    • pp.394-398
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    • 2008
  • One of barely water soluble ketones, acetophenone (AP) was dissolved in methanol and then was mixed with aqueous solution of C. I. Red Acid 114. In order to find out the role of AP in the dyeing process the rate constants and the activation parameters were calculated. The rate for the dyeing with AP was faster than that without it. Because of the reduced temperature dependence by AP the activation energy ($E_a$) for the dyeing with AP was smaller than that without it. With increasing temperature the activation enthalpy (${\Delta}H^*$), the activation entropy (${\Delta}S^*$), and the activation free energy ($G^*$) decreased, which was more noticeable in dyeing with AP. The rate constants and the activation parameters agreed well with the results from the previous reports that the ability of AP to increase disaggregation of dye molecules, loosening the wool fiber, and wickabilty of dyeing solution made it possible to dye wool fiber at low temperature.

The Influence of Cyclic-bending Moment on the Delamination Zone and the Fatigue Crack Propagation in A15052/AFRP Laminates (반복-굽힘 모멘트가 A15052/AFRP 적층재의 층간분리 영역과 피로균열진전에 미치는 영향)

  • Song, Sam-Hong;Kim, Cheol-Woong
    • Proceedings of the KSME Conference
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    • 2000.11a
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    • pp.231-237
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    • 2000
  • A15052/AFRP laminates were developed principally to obtain a material with good fatigue strength, in which possible cracks would grow very slowly. Weight savings of more than 30% should be attainable in practice. Also, the crack bridging fibers could still was carry a significant part of the load over the crack, thus the COD and stress intensity factor was reduced at the crack tip. A15052/ AFRP laminates consists of three thin sheets of 5052-H34 aluminum alloy and two layers of [0] unidirectional aramid fiber prepreg. The cyclic-bending moment test was investigated based on applying the five kinds of bending moments. The size of the delamination zone produced between 5052-H34 aluminum alloy sheets and fiber-adhesive layers was measured from ultrasonic C-scan pictures taken around the fatigue crack. In addition, the relationship between the cyclic-bending moment and the delamination zone size was studied and the effect of fiber bridging mechanism was also considered.

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Effect of Neutral Salts on the Reactive Dyeing of Silk(I) -Effect of Cations- (중성염이 견의 반응염색에 미치는 영향(I) - 양이온의 영향-)

  • 도성국;박찬헌;권지윤
    • Textile Coloration and Finishing
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    • v.12 no.6
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    • pp.372-379
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    • 2000
  • Four kinds of neutral salts with different cations, LiCl, NaCl, KCl, and CsCl, were added to the dye bath to accurately understand the effect of cations on the reactive dyeing of silk with C. I. Reactive Black 5. The cations of salts added lowered the negative surface potential of the silk, improving equilibrium adsorption and the accessibility of the dyestuff to the fiber greatly and speeding up the dyeing rate in the order of $Li^+>Na^+>K^+>Cs^+$. The activation energy$(E_a)$ for the dyeing was in the order of$Li^+>Na^+>K^+>Cs^+$ but the activation free energy$(\Delta{G}^*)$, or the real energy barrier for the reaction, was in the order of $Li^+>Na^+>K^+>Cs^+$ because the degree of the contribution of E$^{a}$ to the activation entropy$(\Delta{S}^*)$ was $Li^+>Na^+>K^+>Cs^+$. It was found from this result that LiCl had the strongest lowering effect on the negative surface potential of silk. The decrease in $\Delta{S}^*$ should be attributed to the loosely bonded activated complex of dyestufffs, cations and fiber molecules at transition state. It was clarified from the Bronsted equation that salts had the ionic strength effect and the specific salt effect on the reactive dyeing.

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Effects of High Concentrations of Naftopidil on Dorsal Root-Evoked Excitatory Synaptic Transmissions in Substantia Gelatinosa Neurons In Vitro

  • Uta, Daisuke;Hattori, Tsuyoshi;Yoshimura, Megumu
    • International Neurourology Journal
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    • v.22 no.4
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    • pp.252-259
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    • 2018
  • Purpose: Naftopidil ((${\pm}$)-1-[4-(2-methoxyphenyl) piperazinyl]-3-(1-naphthyloxy) propan-2-ol) is prescribed in several Asian countries for lower urinary tract symptoms suggestive of benign prostatic hyperplasia. Previous animal experiments showed that intrathecal injection of naftopidil abolished rhythmic bladder contraction in vivo. Naftopidil facilitated spontaneous inhibitory postsynaptic currents in substantia gelatinosa (SG) neurons in spinal cord slices. These results suggest that naftopidil may suppress the micturition reflex at the spinal cord level. However, the effect of naftopidil on evoked excitatory postsynaptic currents (EPSCs) in SG neurons remains to be elucidated. Methods: Male Sprague-Dawley rats at 6 to 8 weeks old were used. Whole-cell patch-clamp recordings were made using SG neurons in spinal cord slices isolated from adult rats. Evoked EPSCs were analyzed in $A{\delta}$ or C fibers. Naftopidil or prazosin, an ${\alpha}1$-adrenoceptor blocker, was perfused at $100{\mu}M$ or $10{\mu}M$, respectively. Results: Bath-applied $100{\mu}M$ naftopidil significantly decreased the peak amplitudes of $A{\delta}$ and C fiber-evoked EPSCs to $72.0%{\pm}7.1%$ (n=15) and $70.0%{\pm}5.5%$ (n=20), respectively, in a reversible and reproducible manner. Bath application of $100{\mu}M$ prazosin did not inhibit $A{\delta}$ or C fiber-evoked EPSCs. Conclusions: The present study suggests that a high concentration of naftopidil reduces the amplitude of evoked EPSCs via a mechanism that apparently does not involve ${\alpha}1$-adrenoceptors. Inhibition of evoked EPSCs may also contribute to suppression of the micturition reflex, together with nociceptive stimulation.

The Effects of Transcutaneous Electrical Nerve Stimulation and Electroacupuncture Stimulation Therapy on the Current Perception Threshold of Orofacial Region (구강안면영역에서의 경피성 신경자극과 전기침자극요법이 전류인지역치에 미치는 영향)

  • Chung, Jin-Woo
    • Journal of Oral Medicine and Pain
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    • v.24 no.3
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    • pp.301-313
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    • 1999
  • 구강안면동통 환자의 치료법으로 널리 쓰이는 전기요법은 연조직과 신경계 구조물에 대한 치료 시 중요한 역할을 담당하고 있다. 저자는 현재 구강안면동통의 치료법으로 널리 쓰이고 있는 전기요법들 중 경피성 신경자극(Transcutaneous electric nerve stimulation)과 전기침자극요법(Electroacupuncture stimulation therapy)이 각각의 신경섬유에 미치는 효과를 평가하고자 정상 성인 남녀 29명에게 경피성 신경자극 및 전기침자극을 시행하고 시행 전 및 시행 후 삼차신경 영역의 3가지 종류($A{\beta}$, $A{\delta}$, C fiber)의 신경섬유의 전류인지역치(CPT) 변화를 측정하여 그 차이점을 분석하였으며 이를 대조군과 비교하였다. 경피성 신경자극 및 전기침자극 모두에서 대조군에 비해 삼차신경 영역의 모든 신경섬유에 걸쳐 고른 전류인지역치의 증가를 나타내었으며, 경피성 신경자극과 전기침자극 후의 전류인지역치 변화량은 서로 유의할만한 차이를 나타내지 않았다. 이는 경피성 신경자극 과 전기침자극 모두 3가지 종류($A{\beta}$, $A{\delta}$, C fiber)의 감각신경섬유의 전류인지역치에 영향을 미치며, 구강안면동통의 감소에 효과적으로 사용될 수 있으리라 생각된다.

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Diagnosis of Small Fiber Neuropathy: Usefulness of Skin Biopsy (소섬유신경병증의 진단: 피부생검의 유용성)

  • Kim, Sooyoung;Sohn, Eun Hee
    • Journal of Electrodiagnosis and Neuromuscular Diseases
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    • v.20 no.2
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    • pp.77-83
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    • 2018
  • Small fiber neuropathy (SFN) mainly affects thinly myelinated $A{\delta}$-fibers and unmyelinated C-fibers presented with neuropathic pain like burning feet or numbness. Many conditions are known as a causes of SFN, metabolic derangement, especially glucose intolerance, is the most frequent cause of SFN. It has been hard to diagnose SFN because there has been lack of specialized test for small nerve fiber. Quantification of intraepidermal nerve fiber density using skin biopsy is promising method to diagnose SFN. A skin biopsy also could give helps to research pathophysiology of SFN by specialized stain method.

Characterization of Electroacupuncture Effects on the Responses of Rat Dorsal Horn Neurons to Noxious Stimulation (전침자극이 흰쥐척수후각세포의 유해자극반응에 미치는 효과의 특성)

  • Shin, Hong-kee;Park, Dong-suk;Lee, Seo-eun;Kim, Jin-hyuk
    • Journal of Acupuncture Research
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    • v.19 no.4
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    • pp.167-182
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    • 2002
  • This experiment was designed to investigate the effects of electroacupuncture (EA) on chronic pains and factors that affected EA effects. The responses of wide dynamic range (WDR) cells to electrical stimulation of $A{\delta}$ & C afferent fibers were used as an index of pain in rats with chronic pains induced by intraplantar injection of complete Freund's adjuvant or peripheral nerve injury. In rats with chronic pains, low (2Hz) and high (100Hz) frequency EA stimulation applied to zusanli caused the inhibition of WDR cell responses in about 60% of rats and the inhibitory actions were dependent on the stimulus strength. EA stimulation also induced an excitation of WDR cell responses in 23.9% of rats and no effect in 15.8% of rats. However, it seemed that in normal rats compared to the rat with chronic pains, the incidence of which EA stimulation caused the excitation or no effect was high. Reversible spinalization almost completely blocked EA-induced inhibitory or excitatory effects. EA stimulation more frequently induced the excitation of WDR cell responses in lightly anesthetized (0.6%) rats and the enhanced responses of WDR cells were inhibited by EA stimulation in the rat anesthetized with 1.5% enflurane. These experimental findings suggest that in rats with chronic pain, EA stimulation inhibited WDR cell responses to slow $A{\delta}$ and C fiber stimulation and EA-induced inhibitory action was under the control of descending inhibitory system and degree of anesthesia.

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