• Title/Summary/Keyword: B-contraction

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COUPLED COINCIDENCE POINT RESULTS FOR GENERALIZED SYMMETRIC MEIR-KEELER CONTRACTION ON PARTIALLY ORDERED METRIC SPACES WITH APPLICATION

  • Deshpande, Bhavana;Handa, Amrish
    • The Pure and Applied Mathematics
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    • v.24 no.2
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    • pp.79-98
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    • 2017
  • We establish a coupled coincidence point theorem for generalized compatible pair of mappings $F,G:X{\times}X{\rightarrow}X$ under generalized symmetric Meir-Keeler contraction on a partially ordered metric space. We also deduce certain coupled fixed point results without mixed monotone property of $F:X{\times}X{\rightarrow}X$. An example supporting to our result has also been cited. As an application the solution of integral equations are obtain here to illustrate the usability of the obtained results. We improve, extend and generalize several known results.

EMPLOYING α-ψ-CONTRACTION TO PROVE COUPLED COINCIDENCE POINT THEOREM FOR GENERALIZED COMPATIBLE PAIR OF MAPPINGS ON PARTIALLY ORDERED METRIC SPACES

  • Deshpande, Bhavana;Handa, Amrish
    • The Pure and Applied Mathematics
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    • v.25 no.2
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    • pp.73-94
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    • 2018
  • We introduce some new type of admissible mappings and prove a coupled coincidence point theorem by using newly defined concepts for generalized compatible pair of mappings satisfying ${\alpha}-{\psi}$ contraction on partially ordered metric spaces. We also prove the uniqueness of a coupled fixed point for such mappings in this setup. Furthermore, we give an example and an application to integral equations to demonstrate the applicability of the obtained results. Our results generalize some recent results in the literature.

Contractile and Electrical Responses of Guinea-pig Gastric Smooth Muscle to Bradykinin

  • Kim, Chul-Soo;Jun, Jae-Yeoul;Kim, Sung-Joon;So, In-Suk;Kim, Ki-Whan
    • The Korean Journal of Physiology
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    • v.29 no.2
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    • pp.233-241
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    • 1995
  • The nonapeptide bradykinin has been shown to exhibit an array of biological activities including relaxation/contraction of various smooth muscles. In order to investigate the effects of bradykinin on the contractility and the electrical activity of antral circular muscle of guinea-pig stomach, the isometric contraction and membrane potential were recorded. Also, using standard patch clamp technique, the $Ca^{2+}-activated$ K currents were recorded to observe the change in cytosolic $Ca^{2+}$ concentration. $0.4 {\mu}M$ bradykinin induced a triphasic contractile response (transient contraction-transient relaxation-sustained contraction) and this response was unaffected by pretreatment with neural blockers (tetrodotoxin, atropine and guanethidine) or with apamin. Bradykinin induced hyperpolarization of resting membrane potential and enhanced the amplitude of slow waves and spike potentials. The enhancement of spike potentials was blocked by neural blockers. Both the bradykinin-induced contractions and changes in membrane potential were reversed by the selective $B_2$-receptor antagonist $(N{\alpha}-adamantaneacetyl-_{D}-Arg-[Hyp, Thy,_{D}-Phe]-bradykinin)$. In whole-cell patch clamp experiment, we held the membrane potential at -20 mV and spontaneous and transient changes of Ca-activated K currents were recorded. Bradykinin induced a large transient outward current, consistent with a calcium-releasing action of bradykinin front the intracellular calcium pool, because such change was blocked by pretreatment with caffeine. Bradykinin-induced contraction was also blocked by pretreatment with caffeine. From these results, it is suggested that bradykinin induces a calciumrelease and contraction through the $B_{2}$ receptor of guinea-pig gastric smooth muscle. Enhancement of slow wave activity is an indirect action of bradykinin through enteric nerve cells embedded in muscle strip.

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Comparison of Chest Mobility, Diaphragm Movement, and Lung Capacity Between With and Without Bras in a Healthy 20s Adult Women (건강한 20대 성인여성의 브래지어 착용 여부에 따른 흉곽 가동성과 가로막 움직임 및 폐활량에 대한 비교)

  • Jeong, Ah-Reum;Lee, Ji-Hyun;Choung, Sung-Dae
    • Journal of the Korea Convergence Society
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    • v.12 no.3
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    • pp.281-286
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    • 2021
  • This study aims to compare chest mobility, diaphragm contraction, and lung capacity when wearing a bra and per breast size. The subjects of this study included 10 adult women who were attending Chungnam B University: 5 women who wear underwear size 75A (group A) and 5 who wear underwear size 85B (group B). The chest mobility using a tape measure, the diaphragm contraction using ultrasound, and the lung capacity was measured using a Pony FX before and after bra wear. The chest mobility and diaphragm contraction were significantly reduced when bras were worn in group A and B. Lung capacity was significantly decreased only in group A. There was no significant difference between the groups. This study suggests that women's bras can have a negative effect on diaphragm movement, chest mobility, and lung capacity.

The Role of $Ca^{++}$ on the Superprecipitation of the Contractile Protein (골격근 Contractile Protein에 대한 $Ca^{++}$의 영향)

  • Park, C.W.;Chung, M.H.;Oh, J.S.
    • The Korean Journal of Pharmacology
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    • v.8 no.2
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    • pp.55-61
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    • 1972
  • Superprecipitation of actomyosin has been considered to be an in vitro model of the muscle contraction. The superprecipitation and ATPase activity (which supplies the energy for contraction) are influenced by several factors which are the large amount of changes in ionic strength, Mg and ATP concentrations. But those behaviors are found to be promptly influenced by the change in a small range of calcium concentration which can be controlled by the cellular function of muscle physiologically only in the presence of the modullatory proteins, tropomyosin and troponin. In order to elucidate the precise roles of calcium in the muscle contraction and relaxation, the effects of calcium on the actin- myosin interaction was observed in the presence of tropomyosin and troponin using the superprecipitation system. The results are summarized as follows: 1. EGTA (glycol ether diaminetetraacetic acid)prolonged the initiation of the superprecipitation of natural actomyosin. 2. Superprecipitation curve was declined by adding EGTA at the time when tile curve reached the half- maximum. The degree of declining was proportional to the amount of EGTA added. Especially, upon adding 0.25 mM EGTA the curve was lowered to the level before the protein superprecipitated. But addition of EGTA did not affect the curve after attaining the maximum. 3. Superprecipitation of Perry myosin B was not affected by EGTA added both before and during the course of the reaction. 4. Tropomyosin did not change the response of Perry myosin B to EGTA added at any time of the reaction. 5. Troponin also did not change the response of Perry myosin B to EGTA. 6. Both tropomyosin and troponin together rendered the Perry myosin B to obtain the same response as natural actomyosin to EGTA. 7. It was concluded that actin-myosin interaction was influenced by the minute change of calcium concentration only in the presence of both tropomyosin and troponin. We could reproduce the contraction and relaxation of the muscle in vitro under the presence of ATP by changing the calcium concentration.

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Endothelium-dependent Contraction of Aorta in One-kidney, One-clip Goldblatt Hypertensive Rat

  • Jeon, Byeong-Hwa;Lee, Kug-Hee;Kim, Hoe-Suk;Kim, Se-Hoon;Chang, Seok-Jong
    • The Korean Journal of Physiology
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    • v.30 no.2
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    • pp.269-278
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    • 1996
  • The mechanism of impaired endothelium-dependent relaxation in the aorta of one-kidney, one clip Goldblatt hypertensive (1K,1C-GBH) rats was investigated. 8 week-old Wistar-Kyoto (WKY) rats were made hypertensive by left renal artery stenosis with contralateral nephrectomy. Endothelium-dependent relaxation was significantly reduced in 1K,1C-GBH rats as compared with WKY rats. However, the relaxation by sodium nitroprusside in 1K,1C-GBH rats was not reduced as compared with WKY rats. The impairment of endothelium-dependent relaxation in 1K,1C-GBH rats was partially restored by the pretreatment of indomethacin or SQ29548. When the nitric oxide production was inhibited by L-nitroarginine methyl ester, acetylcholine (ACh) induced a endothelium-dependent contraction that was greater in 1K,1C-GBH rats than in WKY rats. Endothelium-dependent contraction by ACh was completely abolished by indomethacin or SQ29548. However, imidazole, tranylcypromine and superoxide dismutase did not affect the endothelium-dependent contraction in 1K,1C-GBH rats. These results suggest that impaired endothelium-dependent relaxation in the 1K,1C-GBH rats might be due to the simultaneous release of EDCF, and that prostaglandin B2 may be involved as a mediator of endothelium-dependent contraction.

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The Effect of Mobilization Combined with Shoulder Active Contraction of Depth between the Coracoid Process and Humeral Head (어깨의 능동 수축을 동반한 관절가동술이 부리돌기와 위팔뼈 머리 사이의 거리에 미치는 영향)

  • Sun-min Kim;Sang-hun Jang
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.29 no.2
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    • pp.69-75
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    • 2023
  • Purpose: This study examined the distance between the coracoid process and the humeral head using an ultrasonography device when shoulder active contraction were applied according to the guided direction in the end range of shoulder mobilization. This study aims to provide essential data on treating shoulder disease patients. Methods: The subjects of this study were 20 adults with healthy shoulder joints. ultrasonography (US) equipment was used to examine shoulder joint mobilization under two conditions: (1) anteroposterior (AP) joint mobilization and (2) superoinferior (SI) joint mobilization. Shoulder active contraction was assessed in the end range. The distance between the coracoid process and the humeral head was measured. A linear probe was used for US; the frequency was set to 7.5MHz, and the US image display method was set to B-mode. The US measurement values were measured in (1) the starting position, (2) the end range position, and (3) the end range position of the shoulder active contraction, and the moving distance was drawn in a straight line through the US image. The distance was determined as the measurement value, and the average values were compared. Reults: The results were as follows: (1) the measured AP Joint mobilization increased by an average of .52cm from the end range of the joint mobilization with shoulder active contraction; (2) the measured SI Joint mobilization increased by an average of .49cm from the end range of the joint. Conclusion: When shoulder mobilization is applied, the distance between the coracoid process and the humeral head increases when muscle contraction occurs through shoulder active contraction in the end range, according to the therapist's guidance. Therefore, shoulder mobilization combined with shoulder active contraction is an effective treatment method for patients with shoulder injuries.

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Pharmacological Actions of the Combined Preparations, 'Sahyangsohap-won' and 'Woohwangporyong-hwan' (사향소합원 및 우황포룡환의 약효 연구)

  • Lee, Eun-Bang;Han, Yong-Nam
    • Korean Journal of Pharmacognosy
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    • v.17 no.4
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    • pp.292-301
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    • 1986
  • The combined preparations of the traditional Korean prescriptions, Sahyangsohap-won (A1) and Woohwangporyong-hwan (B1) were evaluated on pharmacological actions in rats and mice, in parallel with the preparations of their modified prescriptions (A2 and B2). The acute toxicities of the four preparations were very low of which $LD_{50}$ values were more than 4g/kg, p.o. and no systematic symptoms were found at the doses. All the preparations showed sedative action by prolongation of sleeping time induced with hexobarbital sodium. The action was more potent in the modified preparations than in the original ones. All the preparations had no anticonvulsant action both in chemoshock seizures induced by pentetrazole and strychnine and in electroshock seizure. In rat fundus preparation, A1 and A2 elicited strong contraction at the concentration of $1{\times}10^{-3}\;g/ml$ in bath, whereas B1 and B2 did neither contraction nor relaxation at the same concentration. The four preparations had no inhibitory effect against acetylcholine induced spasm. In rat intestinal preparation, the four preparations exhibited neither contraction nor relaxation. However, A1 and A2 had antagonistic effect against spasm at the concentration of $1{\times}10^{-3}\;g/ml$. Single administration of each preparation at the dose of 0.24g/kg, p.o. stimulated the secretion of pepsin in rat stomach without inciting the secretion of gastric juice. Their stimulating actions were more marked in B1 and B2 than in A1 and A2, and were more promptly exhibited in the modified preparations (A2 and B2). Accelerating action of bile secretion by single administration of each preparation was found at the dose of 0.24g/kg, p.o. in rats. All the preparations except A2 also stimulated the secretion of bile acid.

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COMMON COUPLED FIXED POINT THEOREM UNDER GENERALIZED MIZOGUCHI-TAKAHASHI CONTRACTION FOR HYBRID PAIR OF MAPPINGS GENERALIZED MIZOGUCHI-TAKAHASHI CONTRACTION

  • DESHPANDE, BHAVANA;HANDA, AMRISH
    • The Pure and Applied Mathematics
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    • v.22 no.3
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    • pp.199-214
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    • 2015
  • We establish a common coupled fixed point theorem for hybrid pair of mappings under generalized Mizoguchi-Takahashi contraction on a noncomplete metric space, which is not partially ordered. It is to be noted that to find coupled oincidence point, we do not employ the condition of continuity of any mapping involved therein. An example is also given to validate our results. We improve, extend and generalize several known results.

Contractile Response of Methylene Blue on Vascular Smooth Muscles - Rabbit Thoracic Aorta and Porcine Mesenteric Artery - (혈관평활근에 대한 Methylene Blue의 수축작용 - 가토흉부대동맥근과 돼지장간막동맥근 -)

  • Baik, Yung-Hong;Choi, Soo-Yong;Kim, Jae-Ha;Cho, Nam-Kee
    • The Korean Journal of Pharmacology
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    • v.26 no.1
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    • pp.13-23
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    • 1990
  • Methylene Blue (MeB) and gentian violet $(10^{-6}{\sim}10^{-4}\;M)$ produced contractions in isolated thoracic aortic preparations of rabbits in a dose-dependent fashion, while other dyes, evans blue and eosine yellowish, did not affect the basal tension in the same range of doses. Porcine mesenteric arterial rings also responded to MeB with dose-dependent contractions. Single dose of $10^{-4}$ M MeB produced a biphasic response: contraction followed by relaxation. The contraction developed slowly within $2{\sim}4$ min and peaked in about 20 minutes and then slowly relaxed to the basal level. Tyramine $(10^{-4}\;M)$ also induced contraction but it developed faster and was more persistent than that of MeB. While the tyramine-induced tension was reproducible, the MeB-induced one wat not reiterable until 3 to 5 hours after washing out the MeB. Adding $10^{-4}$ M MeB further potentiated the contraction induced by $10^{-4}$ M tyramine. However, the MeB contraction was not affected by further addition or tyramine. Both tyramine- and MeB-induced tensions were abolished or significantly inhibited by pretreatment with various drugs acting on the sympathetic nervous system. The tyramine-induced tension was more sensitive to guanethidine and 6-hydroxydopamine than the MeB-induced tension, while the latter was more sensitive to $Ca^{2+}-free$ PSS and reserpine. But they have similar sensitivity to prazosin. The MeB-induced tension was significantly inhibited but not abolished by 6-hydroxydopamine pretreatment. However, either tyramine or 6-hydroxydopamine could not affect the basal tension of the ring that MeB once had been tested. These results suggest that MeB-induced contractions of rabbit thoracic aorta and porcine mesenteric artery result from a release of endogenous norepinephrine from adrenergic nerve endings and are dependent in part on extracellular calcium, and that the potency of MeB to release or to deplete norepinephrine is greater than that of either tyramine or 6-hydroxydopamine.

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