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Botulinum toxin type A (BoNT-A) produced by the bacterium Clostridium botulinum is a potent inhibitor of acetylcholine release in the neuromuscular junction and has been used to treat many disorders related to excessive muscle contraction. However, BoNT-A has recently been used in pain therapy to treat myofascial pain, low back pain and various types of headaches, including migraine. The purpose of this study is to investigate the antinociceptive effect of BoNT-A and its underlying mechanism in the rat formalin inflammatory pain model. BoNT-A (3.5, 7, 15 and 30 U/kg) or vehicle was administered to the plantar surface of the right hindpaw of male Sprague-Dawley rats. BoNT-A dose-dependently (P<0.05) inhibited formalin-induced nociceptive behavior during phase 2 but not during phase 1 when administered 5 h to 12 days before formalin challenge. The onset of the antinociceptive effect started at 5 h after pre-treatment and this effect lasted for at least 12 days. BoNT-A (7 U/kg) also reduced edema. Consistent with the lack of effect in the formalin phase 1, BoNT-A, at 15 U/kg, had no effect on acute thermal nociception; no local muscle weakness was observed at this dose. Pre-treatment of rats with BoNT-A (3.5, 7 or 15 U/kg) all significantly reduced formalin-evoked glutamate (Glu) release. These results demonstrate that local peripheral injection of BoNT-A significantly reduces formalin-induced nociceptive behaviors with the absence of obvious muscle weakness. Such an antinociceptive effect of BoNT-A is associated with the inhibition of formalin-induced release of Glu (and/or neuropeptides) from primary afferent terminals. 相似文献
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Taniguchi Hiroya Masuishi Toshiki Kawazoe Akihito Muro Kei Kadowaki Shigenori Bando Hideaki Iino Shuichi Kageyama Rie Yoshino Takayuki 《International journal of clinical oncology / Japan Society of Clinical Oncology》2021,26(11):2017-2024
International Journal of Clinical Oncology - Napabucasin is an oral NAD(P)H:quinone oxidoreductase 1 bioactivatable agent that generates reactive oxygen species, is hypothesised to affect multiple... 相似文献
25.
Kitamura Kei Shida Dai Sekine Shigeki Ahiko Yuka Nakamura Yuya Moritani Konosuke Tsukamoto Shunsuke Kanemitsu Yukihide 《International journal of clinical oncology / Japan Society of Clinical Oncology》2021,26(9):1671-1678
International Journal of Clinical Oncology - The most widely accepted staging system for colorectal cancer (CRC) is the tumor-node-metastasis (TNM) classification. In Japan, the Japanese... 相似文献
26.
Evidence of a non-specific effect of balance training on postural control mechanisms suggests that balance training during mechanically unperturbed standing may improve postural corrective responses following external perturbations. The purpose of the present study was to examine kinematics of the trunk as well as muscular activity of the lower leg and paraspinal muscles during postural responses to support-surface rotations after short-term balance training. Experiments were performed in control (n=10) and experimental (n=11) groups. The experimental group participated in the 3-day balance training program. During the training, participants stood on a force platform and were instructed to voluntarily shift their center of pressure in indicated directions as represented by a cursor on a monitor. Postural perturbation tests were executed before and after the training period: the slow and fast 10° dorsiflexions were induced at angular velocities of approximately 50°s(-1) and 200°s(-1), respectively. In the experimental group, the amplitude of the trunk displacements during slow and fast perturbations was up to 33.4% and 26.7% lower, respectively, following the training. The magnitude of the muscular activity was reduced in both the early and late components of the response. The kinematic parameters and muscular responses did not change in the control group. The results suggest that balance training during unperturbed standing has the potential to improve postural corrective responses to unexpected balance perturbation through (1) improved neuromuscular coordination of the involved muscles and (2) adaptive neural modifications on the spinal and cortical levels facilitated by voluntary activity. 相似文献
27.
Stance instability is seen in late stage Parkinson's disease (PD). Stabilometer-based center-of-pressure (COP) evaluation is an easy, routine method for measuring postural control ability. Most of the stabilometer- and force plate-based studies on upright postural control have discussed horizontal COP component control. Previous studies on vertical component control have been few, and no fractal analysis-based study on the component has been reported. We aimed to show the influence of neurological changes and aging on the vertical component and the difference in fluctuation pattern behavior in healthy young and elderly subjects as well as Parkinsonian patients. Detrended fluctuation analysis was used to study characteristics of fluctuation of vertical ground reaction force. In the three groups, all scaling exponents (α, α1, α2), which are time-correlated data of vertical ground reaction force, had a value >0 and <0.5 (0<α<0.5). Additionally, α and α2 were significantly different between PD and the other groups. Significant differences were observed between PD and the other groups regarding RMS, maximum peak value, and coefficient of variance. We demonstrated statistically significant differences in vertical ground reaction force between Parkinsonian patients and the other groups, suggesting that a neurological influence with PD may be markedly reflected in the vertical ground reaction force. 相似文献
28.
Objective
To review and compare initial high resolution computed tomography (HRCT) findings in patients with metapneumovirus pneumonia and severe acute respiratory syndrome (SARS-Coronovirus).Materials and methods
4 cases of metapneumovirus pneumonia (mean age of 52.3 years) in an institutional outbreak (Castle Peak Hospital) in 2008 and 38 cases of SARS-coronovirus (mean age of 39.6 years) admitted to Tuen Mun hospital during an epidemic outbreak in 2003 were included. HRCT findings of the lungs for all patients were retrospectively reviewed by two independent radiologists.Results
In the metapneumovirus group, common HRCT features were ground glass opacities (100%), consolidation (100%), parenchymal band (100%), bronchiectasis (75%). Crazy paving pattern was absent. They were predominantly subpleural and basal in location and bilateral involvement was observed in 50% of patients. In the SARS group, common HRCT features were ground glass opacities (92.1%), interlobular septal thickening (86.8%), crazy paving pattern (73.7%) and consolidation (68%). Bronchiectasis was not seen. Majority of patient demonstrated segmental or lobar in distribution and bilateral involvement was observed in 44.7% of patients. Pleural effusion and lymphadenopathy were of consistent rare features in both groups.Conclusion
Ground glass opacities, interlobular septal thickening and consolidations were consistent HRCT manifestations in both metapneumovirus infection and SARS. The presence of bronchiectasis (0% in SARS) may point towards metapneumovirus while crazy paving pattern is more suggestive of SARS. 相似文献29.
W Hayashida T Kumada C Kawai 《Nihon rinsho. Japanese journal of clinical medicine》1992,50(2):413-419
The crucial issues in the management of congestive heart failure (CHF) are improvement of depressed myocardial contractility and reduction of excessive load. For this purpose, positive inotropic agents and vasodilators have been developed as new oral drugs. The former include Denopamine which possesses beta 1 stimulating effect, Xamoterol which is a unique agent acting as a beta 1-partial agonist, and Ibopamine, Docarpamine and Phosphodiesterase Inhibitors which possess both inotropic and vasodilating effects and are called "Inodilators". The latter include Angiotensin Converting Enzyme Inhibitors. In addition, new vasodilators, such as, Vasopressin Antagonist have also been developed. However, careful long-term clinical trials are required with regard to the efficacy and adverse effects before these agents are widely used with safety in the management of CHF. 相似文献
30.
Colostrum and breast milk samples were collected from 65 anti-human cytomegalovirus (HCMV) IgG antibody-positive nursing mothers
at 3 days and at 1 month after delivery. The colostrum supernatant from 10 mothers did not exert an inhibitory effect on HCMV-infected
cells. The activity of tumor necrosis factor (TNF)-α was significantly higher in HCMV DNA-negative colostrum than in DNA-positive
breast milk (P<0.05). Also, serum levels of cell-free soluble interleukin-2 receptor (sIL-2R) from mothers of DNA-positive milk at 1 month
after delivery were significantly higher than those of mothers with DNA-negative milk (P<0.05). Interferon (IFN)-γ was detected at very low levels in most samples with no statistical correlation observed between
the study groups, and IL-4 was not detected in any sample. It is likely that levels of cytokines such as sIL-2R in serum are
related to the reactivation of HCMV which occurs locally in the mammary gland of the lactating mother after delivery 相似文献