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131.
Ye Sol Oh Jin Ha Park Sung Wook Han 《Journal of biomolecular structure & dynamics》2013,31(12):3035-3046
Meso-tetrakis(N-methyl pyridinium-4-yl)porphyrin (TMPyP) intercalates between the base-pairs of DNA at a low [TMPyP]/[DNA base] ratio in aqueous solutions and molecular crowding conditions, which is induced by the addition of Poly(ethylene glycol) (PEG). Studied DNA-binding drugs, including TMPyP, 9-aminoacridine, ethidium bromide, and DAPI (4′,6-diamidino-2-phenylindole) showed similar binding properties in the presence or absence of PEG molecules which is examined by circular and linear dichroism. According to the LDr (reduced linear dichroism) results of the binding drugs examined in this work, PEG molecules induced no significant change compared to their binding properties in aqueous buffering systems. These results suggest that the transition moments are not expected to be perturbed significantly by PEG molecules. In this study, the experimental conditions of PEG 8000 were maintained at 35% (v/v) of total reaction volume, which is equal to the optimal molar concentration (0.0536 M as final concentration for PEG 8000) to maintain suitable cell-like conditions. Therefore, there was no need to focus on the conformational changes of the DNA helical structure, such as forming irregular aggregate structures, induced by large quantities of molecular crowding media itself at this stage. 相似文献
132.
Jae-Won Hyun Su-Hyun Kim In Hye Jeong Suk-Won Ahn So-Young Huh Min Su Park Young In Eom In Soo Joo Joong-Yang Cho Eun Bin Cho Ju-Hong Min Byoung Joon Kim Nam-Hee Kim Jeeyoung Oh Kee Duk Park Ho Jin Kim 《PloS one》2015,10(5)
Objectives
Early identification of suboptimal responders to multiple sclerosis (MS) treatment is critical for optimizing therapeutic decisions. The Rio score (RS) and modified Rio score (MRS) were developed to discriminate the responses to interferon-beta (IFNB) treatment in MS patients. This study was performed to evaluate the utility of RS and MRS in daily clinical practice in Korea.Methods
This was a real-world setting, multicenter, retrospective study of MS patients treated with IFNB from 10 hospitals in Korea. We investigated whether the RS and MRS at the early stage of IFNB therapy could predict treatment responses over 3 years. Suboptimal treatment responses at 3 years were defined as the presence of clinical relapse and/or EDSS progression and/or patients who had been treated with INFB for at least for 1 year and therapy was switched due to perceived treatment failure during the 2 years of follow-up.Results
Seventy patients (50 females and 20 males) were enrolled; 92% (12/13) of patients with high RS and 86% (12/14) of patients with high MRS (score 2 or 3) were suboptimal responders, whereas 93% (53/57) of patients with low RS and 93% (52/56) patients with low MRS (score 0 or 1) showed optimal responses. New active lesions on MRI with clinical relapse in high RS and MRS were the most common combination in suboptimal responders.Conclusions
We confirmed that RS and MRS at 6–15 months of IFNB therapy were useful for predicting poor responders over 3 years. 相似文献133.
Han Gil Seo Nam-Jong Paik Shi-Uk Lee Byung-Mo Oh Min Ho Chun Bum Sun Kwon Moon Suk Bang 《PloS one》2015,10(6)
Background
Botulinum toxin type A is widely used for treating spasticity. Neuronox (Neu-BoNT/A), a newly manufactured botulinum toxin a, has not yet been investigated for its efficacy and safety in the treatment of post-stroke upper limb spasticity.Objective
We evaluated the efficacy and safety of Neuronox (Neu-BoNT/A) compared with BOTOX (onabotulinum toxin A) for treating post-stroke upper limb spasticity.Methods
In total, 196 stroke patients with moderate to severe upper limb spasticity were randomly assigned to either Neuronox or BOTOX intervention. The wrist flexors were mandatory and elbow, finger, and thumb flexors were optional muscles to be injected. Assessments were performed at baseline and 4, 8, and 12 weeks after the intervention. The primary outcome measure was the change from baseline of the Modified Ashworth Scale (MAS) at the wrist flexors at week 4. Secondary outcome measures included the change of MAS at each visit, response rate, Disability Assessment Scale (DAS), Carer Burden Scale, and Global Assessment of treatment benefit.Results
Primary outcome measures were -1.39±0.79 and -1.56±0.81 in the Neuronox and BOTOX groups, respectively. The difference was within the noninferiority margin of 0.45 (95% upper limit=0.40). There were no significant differences between the groups in the secondary outcome and safety measures, except the change of the MAS at the elbow flexors at week 12 (-0.88±0.75 in the Neuronox group, -0.65±0.74 in the BOTOX group; P=0.0429). Both groups showed significant improvements in the MAS, DAS, and Carer Burden Scale at weeks 4, 8, and 12.Conclusion
Neuronox showed equivalent efficacy and safety compared with BOTOX for treating post-stroke upper limb spasticity.Trial Registration
ClinicalTrials.gov NCT01313767 相似文献134.
135.
Chang Geun Yoo Hoon Kim Fachuang Lu Ali Azarpira Xuejun Pan Kyeong Keun Oh Jun Seok Kim John Ralph Tae Hyun Kim 《Bioenergy Research》2016,9(1):67-76
Physicochemical characteristics of corn stover pretreated by soaking in aqueous ammonia (SAA) and low-moisture anhydrous ammonia (LMAA) were compared and investigated. The glucan digestibility of the treated biomass reached 90 % (SAA) and 84 % (LMAA). The LMAA pretreatment enhanced the digestibility by cleaving cross-linkages between cell wall components, whereas the SAA pretreatment additionally improved the digestibility by efficiently removing a major portion of the lignin under mild reaction conditions without significant loss of carbohydrates. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC) revealed the structural and chemical transformations of lignin during the pretreatments. Both pretreatments effectively cleaved ferulate cell wall cross-linking that is associated with the recalcitrance of grass lignocellulosics toward enzymatic saccharification. Extracted lignin from SAA pretreatment was extensively depolymerized but retained “native” character, as evidenced by the retention of β-ether linkages. 相似文献
136.
Moon-Hee Choi Yuanzheng Wu Deuk-Sil Oh Sang-Kyum Kim Hyun-Jae Shin 《Biotechnology and Bioprocess Engineering》2016,21(3):355-363
Mycoleptodonoides aitchisonii (Berk.) Maas Geest. is a culinary mushroom that is recognized as both a nutritious food and an excellent source of bioactive compounds. The purpose of this study was to investigate the antioxidant and antidiabetic properties of M. aitchisonii (MA) both in vitro and in vivo. Total oxyradical scavenging capacity (TOSC) assays revealed that fruit-body extracts had higher antioxidant capacity than mycelial extracts, 0.9-fold higher as measured by peroxynitrite (PN) scavenging assay, 3.7-fold higher as measured by peroxyl radical (PR) scavenging assay, and 1.6-fold as measured by hydroxyl radical (HR) scavenging assay, respectively. The assay of Akt phosphorylation, which is inhibited by Interleukin 6 (IL-6) in the signal transduction pathway for diabetes, was employed to evaluate the antidiabetic activity. Fruit-body extracts significantly increased Akt phosphorylation according to the fruit-body extract concentration, with a maximum increment of 77% at a concentration of 100 μg/mL compared to 51.4% decrement caused by IL-6, but there was no effect of mycelial extracts. Treatment with 5% MA fruit-body powder and streptozotocin (STZ) decreased the blood sugar level to 233.8 mg/dL in diabetic mice compared to 333.8 mg/dL after treatment with STZ alone. Additionally, MA treatment lowered total cholesterol (TC), triglyceride (TG), and LDL-cholesterol levels, while it increased the HDL-cholesterol level. All these findings indicate that fruit-body of M. aitchisonii has potential utility in preventing various diseases such as disorders of sugar and lipid metabolism. 相似文献
137.
Asymmetric cell division is a universal strategy to generate diverse cell types necessary for patterning and proliferation of all eukaryotes. The development of haploid male gametophytes (pollen grains) in flowering plants is a remarkable example in which division asymmetry governs the functional specialization and germline differentiation essential for double fertilization. The male gametophyte is patterned via two mitotic divisions resulting in three highly differentiated daughter cells at maturity, a vegetative cell and two sperm cells. The first asymmetric division segregates a unique male germ cell from an undetermined haploid microspore and is executed in an elaborate sequence of cellular events. However the molecular mechanisms governing the division asymmetry in microspores are poorly understood. Recently we studied the phenotype of sidecar pollen (scp) mutants in detail, and demonstrated a requirement of SCP for both the correct timing and orientation of microspore division. SCP is a microspore-specific member of the LOB/AS2 domain family (LBD27/ASL29) showing that a plant-specific regulator plays a key role in oriented division of polarized microspores. Identification of SCP will serve as a new platform to further explore the largely unknown molecular networks regulating division asymmetry in microspores that establishes the male germline in flowering plants.Key words: sidecar pollen, microspore division, division asymmetry, male gametophyte development, male germline, LBD/ASL family proteinUnlike animals, flowering plants do not set aside a distinct germline from an early stage of the life cycle. Instead the angiosperm germline or germ cells are only segregated in the male and female gametophytes by a limited number of post-meiotic mitoses.1 However, in common with their metazoan cousins, angiosperms utilize division asymmetry for cellular patterning and differentiation of their germlines. Through the unique patterning of a ‘cell-within-a-cell’ structure with three highly differentiated cells, the male gametophyte (pollen grains) serves its biological role to deliver two sessile male gametes to the female gametophyte. Two sequential but different modes of mitotic divisions pattern the male gametophyte (Fig. 1).2 The first division (of the microspore) is asymmetric giving rise to two completely different daughter cells, a larger vegetative cell that will form the pollen tube and a smaller germ cell that is engulfed within the vegetative cell cytoplasm. The second division (of the germ cell) usually appears symmetric† and produces a pair of linked sperm cells. Microspores artificially induced to undergo symmetric division using microtubule inhibitors lack the germ cell and fail to form the typical three-celled structure showing that asymmetry in microspore division is critical for patterning of the male gametophyte.4Open in a separate windowFigure 1Male gametophyte development in Arabidopsis (upper part) and mutations that block germ cell formation (lower part). (Upper part) Male gametophyte development involves two rounds of mitotic division. Prior to the first division the centrally positioned microspore nucleus migrates towards the radial wall (the future germ cell pole marked with an asterisk). At this eccentric site the polarized microspores undergo oriented mitosis and cytokinesis giving rise to highly unequal daughter cells, a vegetative cell and a germ cell of which the later produces a pair of sperm cells by symmetric division. (Lower part) Mutants that fail to establish a distinct germ cell arising from specific defects are illustrated. Arrows in red indicate the developmental origin of the phenotypic defects in mutants. Note that two daughter nuclei in the mutants are in grey to show that their cell fates have not yet been thoroughly investigated. n, nucleus; Vn, vegetative nucleus; Gn, generative nucleus; Gc, generative (or germ) cell; Sc, sperm cell; WT, wild type; gem1, gemini pollen1; scp, sidecar pollen; tio, two-in-one; hik/tes, hinkel/tetraspore 12a/12b, kinesin-12a/kinesin-12b. 相似文献
138.
139.
Kim SK Kim SR Choi MS Park CE Kim YC Kim KY Whang KS Oh KT Kim IS 《Journal of microbiology and biotechnology》2007,17(10):1700-1703
Microorganisms capable of degrading crude oil were isolated and grown in soybean oil as a sole carbon source. The microbial cultures were used to control green peach aphids in vitro. Approximately 60% mortality of aphids was observed when the cultures were applied alone onto aphids. To examine the cultures as a pesticide formulation mixture, the cultures were combined with a low dose of the insecticide imidacloprid (one-fourth dose of recommended field-application rate) and applied onto aphids. The cultures enhanced significantly the insecticidal effectiveness of imidacloprid, which was higher than imidacloprid alone applied at the low dose. The isolated microorganisms exhibited high emulsifying index values and decreased surface tension values after being grown in soybean oil media. GC/MS analyses showed that microorganisms degraded soybean oil to fatty acids. The cultures were suggested to play the roles of wetting, spreading, and sticking agents to improve the effectiveness of imidacloprid. This is the first report on the control of aphids by using oil-degrading microbial cultures. 相似文献
140.