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91.
Emmanuel S. Buys Yu-Chieh Ko Clemens Alt Sarah R. Hayton Alexander Jones Laurel T. Tainsh Ruiyi Ren Andrea Giani Maeva Clerté Emma Abernathy Robert E. T. Tainsh Dong-Jin Oh Rajeev Malhotra Pankaj Arora Nadine de Waard Binglan Yu Raphael Turcotte Daniel Nathan Marielle Scherrer-Crosbie Stephanie J. Loomis Jae H. Kang Charles P. Lin Haiyan Gong Douglas J. Rhee Peter Brouckaert Janey L. Wiggs Meredith S. Gregory Louis R. Pasquale Kenneth D. Bloch Bruce R. Ksander 《PloS one》2013,8(3)
Primary open angle glaucoma (POAG) is a leading cause of blindness worldwide. The molecular signaling involved in the pathogenesis of POAG remains unknown. Here, we report that mice lacking the α1 subunit of the nitric oxide receptor soluble guanylate cyclase represent a novel and translatable animal model of POAG, characterized by thinning of the retinal nerve fiber layer and loss of optic nerve axons in the context of an open iridocorneal angle. The optic neuropathy associated with soluble guanylate cyclase α1–deficiency was accompanied by modestly increased intraocular pressure and retinal vascular dysfunction. Moreover, data from a candidate gene association study suggests that a variant in the locus containing the genes encoding for the α1 and β1 subunits of soluble guanylate cyclase is associated with POAG in patients presenting with initial paracentral vision loss, a disease subtype thought to be associated with vascular dysregulation. These findings provide new insights into the pathogenesis and genetics of POAG and suggest new therapeutic strategies for POAG. 相似文献
92.
93.
Chang-Mo Oh Kyu-Won Jung Young-Joo Won Aesun Shin Hyun-Joo Kong Jae Kwan Jun Sang-yoon Park 《PloS one》2013,8(8)
Objective
Our study aims to describe changes in carcinoma in situ (CIS) and invasive cervical carcinoma (ICC) in Korean women diagnosed between 1993 and 2009.Methods
All cases of CIS and invasive cervical carcinoma diagnosed from 1993 to 2009 in the Korean National Cancer Incidence database were analyzed. Age-standardized rates (ASRs) and annual percent changes (APCs) in incidence rates were compared according to age and histological type. Additionally, we used Korea National Health and Nutrition Examination Survey (KNHANES) to know the association between screening rate for cervical cancer and incidence rate of cervical cancer.Results
Between 1993 and 2009, 72,240 cases of ICC were reported in Korea. Total incidence rate of ICC was 14.7 per 100,000 females. ASRs of ICC declined 3.8% per year, from 19.3 per 100,000 in 1993 to 10.5 per 100,000 in 2009. Although the overall incidence rate of adenocarcinoma remained stable, invasive squamous cell carcinoma showed a decreasing trend (APC −4.2%). For women aged 60–79 years, ASRs for squamous cell carcinoma increased from 1993 to 2001, and decreased from 2001 to 2009 (APC: −4.6%). Total 62,300 cases of CIS were diagnosed from 1993 to 2009. Total incidence rate of CIS was 12.2 per 100,000 females. ASRs of CIS increased 5.7% per year, from 7.5 per 100,000 in 1993 to 19.0 per 100,000 in 2009. Adenocarcinoma in situ increased 13.2% per year. There was a strong positive correlation between screening rate for cervical cancer and incidence rate for CIS (p-value = 0.03) whereas screening rate showed a strong negative correlation with incidence rate for squamous ICC (p-value = 0.04).Conclusions
The increasing trend in CIS, coupled with a decreasing trend in ICC, suggests the important role of cervix cancer screening. The incidence of adenocarcinoma showed a plateau, but the incidence of adenocarcinoma in situ showed an increasing trend. 相似文献94.
Influenza epidemics arise through the accumulation of viral genetic changes. The emergence of new virus strains coincides with a higher level of influenza-like illness (ILI), which is seen as a peak of a normal season. Monitoring the spread of an epidemic influenza in populations is a difficult and important task. Twitter is a free social networking service whose messages can improve the accuracy of forecasting models by providing early warnings of influenza outbreaks. In this study, we have examined the use of information embedded in the Hangeul Twitter stream to detect rapidly evolving public awareness or concern with respect to influenza transmission and developed regression models that can track levels of actual disease activity and predict influenza epidemics in the real world. Our prediction model using a delay mode provides not only a real-time assessment of the current influenza epidemic activity but also a significant improvement in prediction performance at the initial phase of ILI peak when prediction is of most importance. 相似文献
95.
Jennifer Jooyoun Kim Ji Hyung Kim Young-Kyung Kwon Kae Kyoung Kwon Sung-Hyun Yang Jiyi Jang Soo-Jin Heo Heung-Sik Park Won-Kyo Jung Youngdeuk Lee Do-Hyung Kang Chulhong Oh 《Current microbiology》2013,67(6):742-747
An aerobic, Gram-negative, coccoid to short rod-shaped and non-flagellated marine bacterial strain S354T was isolated from seawater of Micronesia. The strain was capable to degrade agar-forming slight depression into agar plate. Growth occurred at a temperature range of 12–44 °C, a pH range of 5–9, and a salinity range of 1–7 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences suggested that S354T belongs to the family Flammeovirgaceae. The novel strain was most closely related to Limibacter armeniacum YM 11-185T with similarity of 92.5 %. The DNA G+C content was 43.8 mol%. The major fatty acids (>10 %) were iso-C15:0 and C16:1 ω5c. The predominant isoprenoid quinone was determined to be MK-7. Polar lipid profile of S354T consisted of phosphatidylethanolamine, unknown polar lipid, and unknown glycolipids. Based on the phenotypic, phylogenetic, biochemical, and physiological tests conducted in this study, S354T is proposed to represent a type strain of a novel genus and species. The 16S rRNA gene sequence of S354T is registered in GenBank under the accession number JQ639084. The type of strain Algivirga pacifica gen. nov., sp. nov. is S354T (=KCCM 90107T=JCM 18326T). 相似文献
96.
Heather S. Carr Yan Zuo Wonkyung Oh Jeffrey A. Frost 《Molecular and cellular biology》2013,33(14):2773-2786
Net1 is a RhoA guanine nucleotide exchange factor (GEF) that is overexpressed in a subset of human cancers and contributes to cancer cell motility and invasion in vitro. However, the molecular mechanism accounting for its role in cell motility and invasion has not been described. In the present work, we show that expression of both Net1 isoforms in breast cancer cells is required for efficient cell motility. Although loss of Net1 isoform expression only partially blocks RhoA activation, it inhibits lysophosphatidic acid (LPA)-stimulated migration as efficiently as knockdown of RhoA itself. However, we demonstrate that the Net1A isoform predominantly controls myosin light-chain phosphorylation and is required for trailing edge retraction during migration. Net1A interacts with focal adhesion kinase (FAK), localizes to focal adhesions, and is necessary for FAK activation and focal adhesion maturation during cell spreading. Net1A expression is also required for efficient invasion through a Matrigel matrix. Analysis of invading cells demonstrates that Net1A is required for amoeboid invasion, and loss of Net1A expression causes cells to shift to a mesenchymal phenotype characterized by high β1-integrin activity and membrane type 1 matrix metalloproteinase (MT1-MMP) expression. These results demonstrate a previously unrecognized role for the Net1A isoform in controlling FAK activation during planar cell movement and amoeboid motility during extracellular matrix (ECM) invasion. 相似文献
97.
Dong Woo Kang Mi-Kyung Park Hye-Joa Oh Dong-Gun Lee Sung-Hwan Park Kang-Yell Choi Mi-La Cho Do Sik Min 《Molecular and cellular biology》2013,33(14):2760-2772
Interleukin-1β (IL-1β) is a potent proinflammatory and immunoregulatory cytokine playing an important role in the progression of rheumatoid arthritis (RA). However, the signaling network of IL-1β in synoviocytes from RA patients is still poorly understood. Here, we show for the first time that phospholipase D1 (PLD1), but not PLD2, is selectively upregulated in IL-1β-stimulated synoviocytes, as well as synovium, from RA patients. IL-1β enhanced the binding of NF-κB and ATF-2 to the PLD1 promoter, thereby enhancing PLD1 expression. PLD1 inhibition abolished the IL-1β-induced expression of proinflammatory mediators and angiogenic factors by suppressing the binding of NF-κB or hypoxia-inducible factor 1α to the promoter of its target genes, as well as IL-1β-induced proliferation or migration. However, suppression of PLD1 activity promoted cell cycle arrest via transactivation of FoxO3a. Furthermore, PLD1 inhibitor significantly suppressed joint inflammation and destruction in IL-1 receptor antagonist-deficient (IL-1Ra−/−) mice, a model of spontaneous arthritis. Taken together, these results suggest that the abnormal upregulation of PLD1 may contribute to the pathogenesis of IL-1β-induced chronic arthritis and that a selective PLD1 inhibitor might provide a potential therapeutic molecule for the treatment of chronic inflammatory autoimmune disorders. 相似文献
98.
AbstractThis article describes an electrochemical method to remove bacterial biofilm from a stainless steel (SS) surface using a potential pulse/reverse pulse technique. This technique employs a periodic waveform that consists of anodic and cathodic pulses. The pulses can effectively strip a thin layer of metal off the SS surface, along with the adherent biofilm, in a saline solution. Not only can the pulses effectively remove biofilm from the SS surface, but they also regenerate the original mirror-like shiny surface. The importance of this electrochemical biofilm removal method is its wide applicability for any types of biofilms. That is, instead of directly removing the biofilm, it removes a very thin layer of the metal under the biofilm. Thus, the removal process is independent to the nature of the biofilms. Furthermore, this electrochemical biofilm removal method is rapid (less than 30?s of potential pulse time) and does not require hazardous chemicals. 相似文献
99.
Jeong Won Kang Young Gyu Choi Jun Ha Lee Oh Kuen Kwon Ho Jung Hwang 《Molecular simulation》2013,39(9):829-835
Pure carbon nanotube (CNT) oscillators are compared to the corresponding CNT oscillators encapsulating copper nanowires (Cu@CNTs) by molecular dynamics simulations. The classical oscillation theory provides a fairly good estimate of the mass dependence of the operating frequency when the CNT surface is not deformed by the Cu nanowire. The structural deformations of the CNT induced by the encapsulated copper nanowire have a greater effect on the oscillation frequency than the mass of the copper nanowire. The excess forces of the Cu@CNT oscillator are slightly higher than those of the CNT oscillator and the excess van der Waals forces induced by the inter-wall interactions are 17 times higher than the excess forces induced by the Cu nanowire–CNT interactions. 相似文献
100.
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