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Sung-Min Kim Heejaung Kim Jeong-Seon Lee Kyung Seok Park Gye Sun Jeon Jeeheun Shon Suk-Won Ahn Seung Hyun Kim Kyung Min Lee Jung-Joon Sung Kwang-Woo Lee 《PloS one》2013,8(11)
Background
Patients with ALS may be exposed to variable degrees of chronic intermittent hypoxia. However, all previous experimental studies on the effects of hypoxia in ALS have only used a sustained hypoxia model and it is possible that chronic intermittent hypoxia exerts effects via a different molecular mechanism from that of sustained hypoxia. No study has yet shown that hypoxia (either chronic intermittent or sustained) can affect the loss of motor neurons or cognitive function in an in vivo model of ALS.Objective
To evaluate the effects of chronic intermittent hypoxia on motor and cognitive function in ALS mice.Methods
Sixteen ALS mice and 16 wild-type mice were divided into 2 groups and subjected to either chronic intermittent hypoxia or normoxia for 2 weeks. The effects of chronic intermittent hypoxia on ALS mice were evaluated using the rotarod, Y-maze, and wire-hanging tests. In addition, numbers of motor neurons in the ventral horn of the spinal cord were counted and western blot analyses were performed for markers of oxidative stress and inflammatory pathway activation.Results
Compared to ALS mice kept in normoxic conditions, ALS mice that experienced chronic intermittent hypoxia had poorer motor learning on the rotarod test, poorer spatial memory on the Y-maze test, shorter wire hanging time, and fewer motor neurons in the ventral spinal cord. Compared to ALS-normoxic and wild-type mice, ALS mice that experienced chronic intermittent hypoxia had higher levels of oxidative stress and inflammation.Conclusions
Chronic intermittent hypoxia can aggravate motor neuronal death, neuromuscular weakness, and probably cognitive dysfunction in ALS mice. The generation of oxidative stress with activation of inflammatory pathways may be associated with this mechanism. Our study will provide insight into the association of hypoxia with disease progression, and in turn, the rationale for an early non-invasive ventilation treatment in patients with ALS. 相似文献3.
This study presents a systematic modeling approach for examining the efficiency of the MEOR process based on in situ selective plugging by bacterial biopolymer production and optimization of the nutrient injection strategy to yield the maximum oil recovery. This study focuses on modeling in situ selective plugging by the bacterial biopolymer dextran that is generated by Leuconostoc mesenteroides. Bacterial growth and dextran generation were described by a stoichiometric equation and kinetic reactions using batch model simulation. Based on the parameters for permeability reduction obtained from the sandpack model, the MEOR process was implemented in a pilot-scale system that included a highly permeable thief zone in a low-permeability reservoir. The base MEOR design yielded a 61.5% improvement of the recovery factor compared to that obtained with waterflooding. The parametric simulations revealed that the recovery efficiency was influenced by the amount of dextran, as well as the distribution of dextran, and thus, the injection strategy is critical for controlling the dextran distribution. By incorporating the results from the sensitivity analysis and optimization to determine the optimal design parameters, a 36.7% improvement of the oil recovery was achieved with the optimized MEOR process in comparison with the base case. 相似文献
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Young-Seok Shon Hyung Y. Choi Michael S. Guerrero Chuhee Kwon 《Plasmonics (Norwell, Mass.)》2009,4(2):95-105
This article presents a concise review of preparation methods for transparent nanostructured films, with an emphasis on their
current applications in transmission-localized surface plasmon resonance (T-LSPR) sensing. One of the first methods used for
the fabrication of transparent nanostructured metal films is a direct vacuum evaporation of thin gold films. Self-induced
formations of small gold islands result in transparent nanostructured gold arrays. The most well-established method is a nanosphere
lithography developed by Van Duyne. Nanotriangular island arrays with controlled size and optical properties can be fabricated
by this protocol. A different nanolithography method known as focused ion beam milling is reported and used for the fabrication
of nanohole arrays. Simple assembly of solution-phase synthesized nanoparticles has also been utilized for the preparation
of nanoparticle arrays capable of T-LSPR sensing. Lastly, this article also describes a new preparation strategy, in which
self-assembly/thermolysis of nanoparticle multilayers is employed to obtain transparent nanoisland architectures on glass
substrates. 相似文献
5.
Effects of human amniotic membrane grafts combined with marrow mesenchymal stem cells on healing of full-thickness skin defects in rabbits 总被引:1,自引:0,他引:1
Sung Soo Kim Chang Keun Song Sung Keun Shon Kyu Yeol Lee Chul Hong Kim Myung Jin Lee Lih Wang 《Cell and tissue research》2009,336(1):59-66
We have investigated the wound-healing effects of mesenchymal stem cells (MSCs) in combination with human amniotic membrane
(HAM) when grafted into full-thickness skin defects of rabbits. Five defects in each of four groups were respectively treated
with HAM loaded with autologous MSCs (group A), HAM loaded with allologous MSCs (group B), HAM with injected autologous MSCs
(group C), and HAM with injected allologous MSCs (group D). The size of the wounds was calculated for each group at 7, 12,
and 15 days after grafting. The wounds were subsequently harvested at 25 days after grafting. Sections stained with hematoxylin
and eosin were used to determine the quality of wound healing, as based on the characteristics and amount of granulated tissue
in the epidermal and dermal layers. Groups A and B showed the most pronounced effect on wound closure, with statistically
significant improvement in wound healing being seen on post-operative days 7, 12, and 15. Although a slight trend toward improved
wound healing was seen in group A compared with group B, no statistically significant difference was found at any time point
between the two groups. Histological examination of healed wounds from groups A and B showed a thin epidermis with mature
differentiation and collagen bundle deposition plus recovered skin appendages in the dermal layer. In contrast, groups C and
D showed thickened epidermis with immature epithelial cells and increased fibroblast proliferation with only partially recovered
skin appendages in the dermal layer. Thus, the graft of HAM loaded with MSCs played an effective role during the healing of
skin defects in rabbits, with no significant difference being observed in wound healing between autologous and allologous
MSC transplantation.
This study was supported by research funds from Dong-A University. 相似文献
6.
Chunggab Choi Hye Min Kim Jeeheun Shon Jiae Park Hyeong-Taek Kim Suk Ho Kang Seung-Hun Oh Nam Keun Kim Ok Joon Kim 《Cytotherapy》2018,20(6):820-829
Background
The blood-brain barrier (BBB) presents a significant challenge to the therapeutic efficacy of stem cells in chronic stroke. Various methods have been developed to increase BBB permeability, but these are associated with adverse effects and are, therefore, not clinically applicable. We recently identified that combination drug treatment of mannitol and temozolomide improved BBB permeability in vitro. Here, we investigated whether this combination could increase the effectiveness of stem cell treatment in an animal model of chronic ischemic stroke.Methods
Chronic stroke was induced in rats by middle cerebral artery occlusion (MCAo). After then, rats were administered human umbilical cord–derived mesenchymal stromal cells (hUC-MSCs) by intravenous injection with or without combination drug treatment of mannitol and temozolomide. To evaluate the therapeutic efficacy, behavioral and immunohistochemical tests were performed, and the differences among control, stem cell only, combination drug only and stem cell with combination drug treatment were analyzed.Results
Although no hUC-MSCs were detected in any group, treatment with stem cells and combination drug of mannitol and temozolomide increased the intracerebral delivery of hCD63-positive microvesicles compared with stem cell only treatment. Furthermore, treatment with stem cells and drug combination ameliorated behavioral deficits and increased bromodeoxyuridine-, doublecortin- and Reca-1–positive cells in the perilesional area as compared with other groups.Discussion
The combination drug treatment of mannitol and temozolomide allowed for the efficient delivery of hUC-MSC–derived microvesicles into the brain in a chronic stroke rat model. This attenuated behavioral deficits, likely by improving neural regeneration and angiogenesis. Thus, combination drug treatment of mannitol and temozolomide could be a novel therapeutic option for patients with chronic ischemic stroke. 相似文献7.
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Lee DH Ha JH Kim Y Bae KH Park JY Choi WS Yoon HS Park SG Park BC Yi GS Chi SW 《Biochemical and biophysical research communications》2011,(4):40083-547
Clusterin (CLU) is a multifunctional glycoprotein that is overexpressed in prostate and breast cancers. Although CLU is known to be involved in the regulation of apoptosis and cell survival, the precise molecular mechanism underlying the pro-apoptotic function of nuclear CLU (nCLU) remains unclear. In this study, we identified a conserved BH3 motif in C-terminal coiled coil (CC2) region of nCLU by sequence analysis and characterized the molecular interaction of the putative nCLU BH3 domain with anti-apoptotic Bcl-2 family proteins by nuclear magnetic resonance (NMR) spectroscopy. The chemical shift perturbation data demonstrated that the nCLU BH3 domain binds to pro-apoptotic BH3 peptide-binding grooves in both Bcl-XL and Bcl-2. A structural model of the Bcl-XL/nCLU BH3 peptide complex reveals that the binding mode is remarkably similar to those of other Bcl-XL/BH3 peptide complexes. In addition, mutational analysis confirmed that Leu323 and Asp328 of nCLU BH3 domain, absolutely conserved in the BH3 motifs of BH3-only protein family, are critical for binding to Bcl-XL. Taken altogether, our results suggest a molecular basis for the pro-apoptotic function of nCLU by elucidating the residue specific interactions of the BH3 motif in nCLU with anti-apoptotic Bcl-2 family proteins. 相似文献
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Microbial community analysis of an aerobic nitrifying-denitrifying MBR treating ABS resin wastewater 总被引:1,自引:0,他引:1
A two-stage aerobic membrane bioreactor (MBR) system for treating acrylonitrile butadiene styrene (ABS) resin wastewater was carried out in this study to evaluate the system performance on nitrification. The results showed that nitrification of the aerobic MBR system was significant and the highest TKN removal of approximately 90% was obtained at hydraulic retention time (HRT) 18 h. In addition, the result of nitrogen mass balance revealed that the percentage of TN removal due to denitrification was in the range of 8.7-19.8%. Microbial community analysis based on 16s rDNA molecular approach indicated that the dominant ammonia oxidizing bacteria (AOB) group in the system was a β-class ammonia oxidizer which was identified as uncultured sludge bacterium (AF234732). A heterotrophic aerobic denitrifier identified as Thauera mechernichensis was found in the system. The results indicated that a sole aerobic MBR system for simultaneous removals of carbon and nitrogen can be designed and operated for neglect with an anaerobic unit. 相似文献
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Pruitt JR Batt DG Wacker DA Bostrom LL Booker SK McLaughlin E Houghton GC Varnes JG Christ DD Covington M Das AM Davies P Graden D Kariv I Orlovsky Y Stowell NC Vaddi KG Wadman EA Welch PK Yeleswaram S Solomon KA Newton RC Decicco CP Carter PH Ko SS 《Bioorganic & medicinal chemistry letters》2007,17(11):2992-2997
DPC168, a benzylpiperidine-substituted aryl urea CCR3 antagonist evaluated in clinical trials, was a relatively potent inhibitor of the 2D6 isoform of cytochrome P-450 (CYP2D6). Replacement of the cyclohexyl central ring with saturated heterocycles provided potent CCR3 antagonists with improved selectivity against CYP2D6. The favorable preclinical profile of DPC168 was maintained in an acetylpiperidine derivative, BMS-570520. 相似文献