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101.
102.
Paul S. Sung 《Journal of electromyography and kinesiology》2013,23(3):741-745
Low back pain (LBP) is one of the most common symptoms reported in adults. However, the contribution of postural control on the lumbar spine and hips during squatting has not been carefully investigated in individuals with LBP. The aim of this study was to compare three-dimensional kinematic changes of the lumbar spine and hips between subjects with and without idiopathic chronic LBP during squatting activities. In total, 30 subjects enrolled in the study (15 control subjects and 15 subjects with idiopathic chronic LBP). All participants were asked to perform squatting activities five times repeatedly while holding a load of 2 kg in a basket. The outcome measures included the Oswestry Disability Index (ODI) and kinematic angular displacement for the hips and lumbar spine. The LBP group demonstrated increased range of motion (ROM) in flexion of the dominant (T = ?2.14, p = 0.03) and non-dominant (T = ?2.11, p = 0.03) hips during squatting. The lumbar spine flexion ROM significantly decreased (T = 2.20, p = 0.03). The kinematic changes demonstrated interactions with region × group (F = 5.56, p = 0.02), plane × group (F = 4.36, p = 0.04), and region × plane (F = 2292.47, p = 0.001). The ODI level demonstrated significant interaction on combined effects of body region and plane (F = 4.91, p = 0.03). Therefore, the LBP group utilized a compensation strategy to increase hip flexion with a stiffened lumbar spine in the sagittal plane during squatting. This compensatory kinematic strategy could apply to clinical management used to enhance lumbar spine flexibility in subjects with idiopathic chronic LBP. 相似文献
103.
Jin Sil Chung Seung Baek Lee Seon Ho Park Sung Tae Kang Ah Ram Na Tong-Shin Chang 《Free radical research》2013,47(8):729-737
Reactive oxygen species (ROS) steady-state levels are required for entry into the S phase of the cell cycle in normal cells, as well as in tumour cells. However, the contribution of mitochondrial ROS to normal cell proliferation has not been well investigated thus far. A previous report showed that Romo1 was responsible for the high ROS levels in tumour cells. Here, we show that endogenous ROS generated by Romo1 are indispensable for cell cycle transition from G1 to S phase in normal WI-38 human lung fibroblasts. The ROS level in these cells was down-regulated by Romo1 knockdown, resulting in cell cycle arrest in the G1 phase. This arrest was associated with an increase in the level of p27Kip1. These results demonstrate that mitochondrial ROS generated by Romo1 expression is required for normal cell proliferation and it is suggested that Romo1 plays an important role in redox signalling during normal cell proliferation. 相似文献
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106.
Minkyun Na Bo Yeon Kim Hiroyuki Osada 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):1056-1059
Protein tyrosine phosphatase 1B (PTP1B) appears to be an attractive target for the development of new drugs for type 2 diabetes and obesity. In our preliminary test, a MeOH extract of the stem barks of Sorbus commixta Hedl. (Rosaceae) showed strong PTP1B inhibitory activity. Bioassay?guided fractionation of the MeOH extract resulted in the isolation of two lupane?type triterpenes, lupenone (1) and lupeol (2). Compounds 1 and 2 inhibited PTP1B with IC50 values of 13.7 ± 2.1 and 5.6 ± 0.9 μM, respectively. Kinetic studies revealed that both the compounds 1 and 2 are non?competitive inhibitors of PTP1B that decrease Vmax values with no effect on Km values. 相似文献
107.
Seung Hyun Kim Sin-Duk Jang Ki Yong Lee Sang Hyun Sung 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):230-233
A methanolic extract of dried leaves of Polygala japonica Houtt (Polygalaceae) significantly attenuated nitric oxide production in lipopolysaccharide-simulated BV2 microglia. Five anthraquinones chrysophanol (1), emodin (2), aloe-emodin (3), emodin 8-O-β-D-glucopyranoside (4) and trihydroxy anthraquinone (5), and four flavonoids kaempferol (6), chrysoeriol (7), kaempferol 3-gentiobioside (8) and isorhamnetin (9) were isolated from the methanolic extract using bioactivity-guided fractionation. Among them, compounds 1–4, 6 and 7 showed significant inhibitory effect on lipopolysaccharide-induced nitric oxide production in BV2 microglia at the concentrations ranging from 1.0 to 100.0 μM. 相似文献
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109.
Moon Woo Chun Sung Pil Choi Myong Jung Kim Chol Joon Bae Hyung Ryong Moon Hee-Doo Kim 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):615-616
Abstract Novel 1,3-oxathiolanyl pyrimidine nucleosides with 5-hydroxymethyl substituent were synthesized starting from d-mannose and evaluated for antiviral activities against HIV-1, HSV type 1,2 and HCMV. 相似文献
110.
Jae Young Choi Myung-Pyo Jung Hong-Hyun Park Xue Ying Tao Byung Rae Jin Yeon Ho Je 《Journal of Asia》2013,16(1):75-80
To improve the insecticidal activity of Autographa californica nucleopolyhedrovirus (AcMNPV), using co-expression of Bacillus thuringiensis crystal protein and a Kunitz-type toxin isolated from bumblebee Bombus ignitus venom, a recombinant AcMNPV, ApPolh5-3006BiKTI, expressing Bi-KTI under the control of early promoter from Cotesia plutellae bracovirus (CpBV) was constructed. In this recombinant virus, B. thuringiensis cry1-5 crystal protein gene was introduced into the genome by the fusion of polyhedrin-cry1-5 under the control of polyhedrin gene promoter. RT-PCR analysis indicated that both Bi-KTI and polyhedrin-cry1-5 fusion protein were successfully expressed from the infected cells. In addition, SDS-PAGE revealed that polyhedrin-cry1-5 fusion protein expressed by recombinant viruses was occluded into the polyhedra. ApPolh5-3006BiKTI showed an improved insecticidal activity against larvae of Plutella xylostella and Spodoptera exigua. At low dosage rates, it was more effective against S. exigua than on P. xylostella, but more rapid insecticidal activity was shown in P. xylostella. These results strongly suggest that co-expression of Bt toxin and Kunitz-type toxins could be successfully applied to improve the insecticidal activity of baculoviruses. 相似文献