Neuroinflammation is associated with neurodegenerative diseases,such as Alzheimer's disease,Parkinson's disease,ancamyotrophic lateral sclerosis.Microglia and astrocytes are key regulators of inflammatory resp...Neuroinflammation is associated with neurodegenerative diseases,such as Alzheimer's disease,Parkinson's disease,ancamyotrophic lateral sclerosis.Microglia and astrocytes are key regulators of inflammatory responses in the central nervous system.The activation of microglia and astrocytes is heterogeneous and traditionally categorized as neurotoxi(M1-phenotype microglia and A1-phenotype astrocytes)or neuroprotective(M2-phenotype microglia and A2-phenotype astrocytes).However,this dichotomized classification may not reflect the various phenotypes of microgliaand astrocytes.The relationship between these activated glial cells is also very complicated,and the phenotypic distribution can change,based on the progression of neurodegenerative diseases.A better understanding of the rolesof microglia and astrocytes in neurodegenerative diseases is essential for developing effective therapies.In this review,we discuss the roles of inflammatory response in neurodegenerative diseases,focusing on the contributions of microglia and astrocytes and their relationship.In addition,we discuss biomarkers to measure neuroinflammation andstudies on therapeutic drugs that can modulate neuroinflammation.展开更多
Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus (QTL) mapping and candidate gene analysis using ...Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus (QTL) mapping and candidate gene analysis using whole- genome re-sequencing, we found that Oryza sativa Pseudo-Response Regulator37 (OsPRR37; hereafter PRR37) is respon- sible for the Early heading7-2 (EH7-2)/Heading date2 (Hd2) QTL which was identified from a cross of late-heading rice 'Milyang23 (M23)' and early-heading rice 'H143'. H143 contains a missense mutation of an invariantly conserved amino acid in the CCT (CONSTANS, CO-like, and TOC1) domain of PRR37 protein. In the world rice collection, different types of nonfunctional PRR37 alleles were found in many European and Asian rice cultivars. Notably, the japonica varieties harboring nonfunctional alleles of both Ghd7/Hd4 and PRR37/Hd2 flower extremely early under natural long-day condi- tions, and are adapted to the northernmost regions of rice cultivation, up to 53~ N latitude. Genetic analysis revealed that the effects of PRR37 and Ghd7 alleles on heading date are additive, and PRR37 down-regulates Hd3a expression to suppress flowering under long-day conditions. Our results demonstrate that natural variations in PRR37/Hd2 and GhdT/ Hd4 have contributed to the expansion of rice cultivation to temperate and cooler regions.展开更多
A pintle injector is advantageous for throttling a liquid rocket engine and reducing engine weight. This study ex- plores the effects of momentum ratio and Weber number at various injection conditions on spray charact...A pintle injector is advantageous for throttling a liquid rocket engine and reducing engine weight. This study ex- plores the effects of momentum ratio and Weber number at various injection conditions on spray characteristics of the pintle injector for liquid-gas propellants. A liquid sheet is injected from a center pintle nozzle and it is broken by a gas jet from an annular gap. The pressure drops of propellants, and the pintle opening distance were consi- dered as control variables; using 0.1 -1.0 as a bar for the pressure drop of the liquid injection, a 0.01-4).2 bar for the pressure drop of gas jet and a 0.2 - 1.0 mm for the pintle opening distance. The discharge coefficient was de- creased linearly before the pintle opening distance of 0.75 mm and then, the coefficient was slightly increased. Spray images were captured by a CMOS camera with high resolution. Then, the shadow and reflected images were analyzed. Spray distributions were measured by a pattemator with an axial distance of 50 mm from a pintle tip. Finally, the spray half angles had an exponentially decreasing correlation as a momentum ratio divided by the Weber number. Also, the spray half angles from the spray distribution were underestimated compared to those measured from the captured images.展开更多
The let-7 miRNAwas one of the first miRNAs discovered in the nematode, Caenorhabditis elegans, and its biological functions show a high level of evolutionary conservation from the nematode to the human. Unlike in C. e...The let-7 miRNAwas one of the first miRNAs discovered in the nematode, Caenorhabditis elegans, and its biological functions show a high level of evolutionary conservation from the nematode to the human. Unlike in C. elegans, higher animals have multiple isoforms of let-7 miRNAs; these isoforms share a consensus sequence called the 'seed sequence' and these isoforms are categorized into let-7 miRNA family. The expression of let-7 family is required for developmental timing and tumor suppressor function, but must be suppressed for the self-renewal of stem cells. Therefore, let-7 miRNA biogenesis must be carefully controlled. To generate a let-7 miRNA, a primary transcript is produced by RNA polymerase Ⅱ and then subsequently processed by Drosha/DGCR8, TUTase, and Dicer. Because dysregulation of let-7 processing is deleterious, biogenesis of let-7 is tightly regulated by cellular factors, such as the RNA binding proteins, LIN28A/B and DIS3L2. In this review, we discuss the biological functions and biogenesis of let-7 miRNAs, focusing on the molecular mechanisms of regulation of let-7 biogenesis in ver- tebrates, such as the mouse and the human.展开更多
AIM: To clarify the mechanism underlying the antidiabetic activities of cortex cinnamomi extract (CCE). METHODS: To induce in vivo diabetes, mice were injected with streptozotocin (STZ) via a tail vein (100 mg ...AIM: To clarify the mechanism underlying the antidiabetic activities of cortex cinnamomi extract (CCE). METHODS: To induce in vivo diabetes, mice were injected with streptozotocin (STZ) via a tail vein (100 mg STZ/kg body weight). To determine the effects of CCE, mice were administered CCE twice daily for 7 d by oral gavage starting 1 wk before the STZ injection. Blood glucose and plasma insulin concentration were measured as an index of diabetes. Also, to induce cytotoxicity of RINm5F cells, we treated with cytokines (IL-1β (2.0 ng/mL) and IFN-γ (100 U/mL)). Cell viability and nitric oxide production were measured colorimetrically. Inducible nitric oxide synthase (iNOS) mRNA and protein expression were determined by RT-PCR and Western blotting, respectively. The activation of NF-κβ was assayed by using gel mobility shift assays of nuclear extracts. RESULTS: Treatment of mice with STZ resulted in hyperglycemia and hypoinsulinemia, which was further evidenced by immunohistochemical staining of islets. However, the diabetogenic effects of STZ were completely prevented when mice were pretreated with CCE. The inhibitory effect of CCE on STZ-induced hyperglycemia was mediated through the suppression of iNOS expression. In rat insulinoma RINm5F cells,CCE completely protected against interleukin-1β and interferon-y-mediated cytotoxicity. Moreover, RINm5F cells incubated with CCE showed significant reductions in interleukin-1β and interferon-y-induced nitric oxide production and in iNOS mRNA and protein expression, and these findings correlated well with in vivo observations. CONCLUSION: The molecular mechanism by which CCE inhibits iNOS gene expression appears to involve the inhibition of NF-κβ activation, These results reveal the possible therapeutic value of CCE for the prevention of diabetes mellitus progression,展开更多
Diffusion bonding between aluminum and copper was performed by vacuum hot pressing at temperatures between 623 and 923 K through two thermal processes: hot compression under the deformation rate of 0.2 mrrdmin for 10...Diffusion bonding between aluminum and copper was performed by vacuum hot pressing at temperatures between 623 and 923 K through two thermal processes: hot compression under the deformation rate of 0.2 mrrdmin for 10 rain at pre-set temperatures, and additional pressing at 0.2 mm/min for 20 rain during furnace cooling. After analyzing interface, the feasible diffusion bonding temperature was suggested as 823 K. The three major intermetallic layers generated during diffusion bonding process were identified as AIECu, AlCu+AlaCu4 and Al4Cu9. Furthermore, local hardness values ofAlECU, AlCu+AlaCu4 and Al4Cu9 layers average at (4.97±0.05), (6.33±0.00) and (6.06±0.18) GPa, respectively.展开更多
AIM:To evaluate the potential usefulness of acoustic radiation force impulse (ARFI) images for evaluation of hepatocellular carcinomas (HCC)-associated radiofrequency ablation. METHODS:From January 2010 to June 2010,a...AIM:To evaluate the potential usefulness of acoustic radiation force impulse (ARFI) images for evaluation of hepatocellular carcinomas (HCC)-associated radiofrequency ablation. METHODS:From January 2010 to June 2010,a total of 38 patients with HCC including recurred HCCs after RFA underwent ARFI elastography. The brightness of tumor was checked and the shear wave velocity was measure-d for the-quantification of stiffne-ss. According to theb-rightne-ss,the-tumors we-re-classifie-d as b-righte-r,samecolor and darker compared with adjacent parenchyma. Using the same methods,8 patients with recurred HCCs after RFA state were evaluated about the brightness compared with adjacent RFA ablation area. RESULTS:In the 38 patients with HCCs,20 (52.6%)were brighter than surrounding cirrhotic parenchyma. Another 13 (34.2%) were darker. The others (5 cases,13.2%) were seen as the same color as the adjacent liver parenchyma. Post-RFA lesions were darker than previous tumor and surrounding parenchyma in all 38 cases. However,recurred HCCs were brighter than the treated site in all 8 cases. CONCLUSION:Using ARFI technique is helpful for differential diagnosis in order to detect recurred HCCs more easily in patients with confusing status.展开更多
AIM: To compare the histopathologic features of intestinal tuberculosis (ITB) and Crohn’s disease (CD) and to identify whether polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) would be helpful for di...AIM: To compare the histopathologic features of intestinal tuberculosis (ITB) and Crohn’s disease (CD) and to identify whether polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) would be helpful for differential diagnosis between ITB and CD.METHODS: We selected 97 patients with established diagnoses (55 cases of ITB and 42 cases of CD) who underwent colonoscopic biopsies.Microscopic features of ITB and CD were reviewed,and eight pathologic parameters were evaluated.Nine cases of acid fast bacilli culture-positive specimens and 10 normal colonic tissue specimens were evaluated as the positive and negative control of the TB-PCR test,respectively.PCR assays were done using two commercial kits: kit <A> detected IS6110 and MPB64,and kit <B> detected IS6110 only;a manual in-house PCR method was also performed on formalin-fi xed,paraffi n-embedded colonoscopic biopsy specimens.RESULTS: Statistically significant differences were noted between ITB and CD with regard histopathologic criteria: size of granulomas (P = 0.000),giant cells (P = 0.015),caseation necrosis (P = 0.003),confluent granulomas (P = 0.001),discrete granulomas (P = 0.000),and granulomas with lymphoid cuffs (P = 0.037).However,29 cases (52.7%) of ITB showed less than fi ve kinds of pathologic parameters,resulting in confusion with CD.The sensitivities and specificities of the TB-PCR test by kit <A>,kit <B>,and the in-house PCR method were 88.9% and 100%,88.9% and 100%,and 66.7% and 100% in positive and negative controls,respectively.The PCR test done on endoscopic biopsy specimens of ITB and CD were signifi cantly different with kit <A> (P = 0.000) and kit <B> (P = 0.000).The sensitivities and specifi cities of TB-PCR were 45.5% and 88.1%,36.4% and 100%,and 5.8% and 100%,for kit <A> and kit <B> and inhouse PCR method on endoscopic biopsy specimens.Among the 29 cases of histopathologically confusing CD,10 cases assayed using kit <A> and 6 cases assayed using kit <B> were TB-PCR positive.A combination of histologic fi ndings and TB-PCR test展开更多
A differential-speed rolling(DSR) was applied to AZ31 magnesium alloy sample at different rolling temperatures of 473,523,573,and 623 K with 1-pass and 2-pass operations.The microstructural evolution and mechanical pr...A differential-speed rolling(DSR) was applied to AZ31 magnesium alloy sample at different rolling temperatures of 473,523,573,and 623 K with 1-pass and 2-pass operations.The microstructural evolution and mechanical properties of the deformed samples were investigated.The rolling temperature was found to be an important parameter affecting the microstructural development.After DSR at 473 K,the microstructure was more homogeneous than that obtained after deformation by equal-speed rolling(ESR).The fully recrystallized microstructures were generated after DSR at 573 and 623 K.As to mechanical properties,the yield strength(YS) and ultimate tensile strength(UTS) decreased monotonously with increasing rolling temperature.In contrast,the elongation of the DSR-deformed samples was improved as the rolling temperature increased.The strain hardening exponent(n) calculated by Hollomon equation increased with increasing the rolling temperature,which would explain an increase in the uniform elongation.展开更多
A mobile molecular Doppler wind lidar at an eye-safe wavelength of 355 nm based on double-edge technique is being built in Hefei (China) for wind measurement from 10-to 40-km altitude. The structure of this lidar sy...A mobile molecular Doppler wind lidar at an eye-safe wavelength of 355 nm based on double-edge technique is being built in Hefei (China) for wind measurement from 10-to 40-km altitude. The structure of this lidar system is described. A triple Fabry-Perot etalon is employed as a frequency discriminator whose parameters are optimized. The receiver system is designed to achieve compactness and stability by putting in a standard 19-inch socket bench. Simulation results show that within the wind speed dynamic range of ±100 m/s, the horizontal wind errors due to noise are less than 1 m/s bdow 20-km altitude for 100-m vertical resolution, and less than 5.5 m/s from 20 km up to 40 km for 500-m vertical resolution with 400-mJ laser energy, 30-min temporal resolution, and a 45-cm aperture telescooe.展开更多
Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long- distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we ide...Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long- distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we identified a T-DNA insertional mutant of Oryza sativa DNA BINDING WITH ONE FINGER 11 (OsDOF11), which is expressed in the vascular cells of photosynthetic organs and in various sink tissues. The osdofll mutant plants are semi-dwarf and have fewer tillers and smaller panicles as compared with wild-type (WT) plants. Although sucrose enhanced root elongation in young WT seedlings, this enhance- ment did not occur in osdof11 seedlings due to reduced sucrose uptake. Sugar transport rate analyses revealed that less sugar was transported in osdofll plants than in the WT. Expression of four Sucrose Transporter (SUT) genes-OsSUT1, OsSUT3, OsSUT4, and OsSUT5-as well as two Sugars Will Eventually be Exported Transporters (SWEET) genes, OsSWEETll and OsSWEET14, was altered in various organs of the mutant, including the leaves. Chromatin immunoprecipitation assays showed that OsDOFll directly binds the promoter regions of SUT1, OsSWEETll, and OsSWEET14, indicating that the expression of these transporters responsible for sucrose transport via apopiastic loading is coordinately controlled by OsDOFll. We also observed that osdofll mutant plants were less susceptible to infection byXanthomonas oryzae pathovar oryzae, suggesting that OsDOFll participates in sugar distribution during pathogenic in- vasion. Collectively, these results suggest that OsDOFll modulates sugar transport by regulating the expression of both SUT and SWEET genes in rice.展开更多
Salt tolerance is an important constrain for rice, which is generally categorized as a typical glycophyte. Soil salinity is one of the major constraints affecting rice production worldwide, especially in the coastal a...Salt tolerance is an important constrain for rice, which is generally categorized as a typical glycophyte. Soil salinity is one of the major constraints affecting rice production worldwide, especially in the coastal areas. Susceptibility or tolerance of rice plants to high salinity is a coordinated action of multiple stress responsive genes, which also interacts with other components of stress signal transduction pathways. Salt tolerant varieties can be produced by marker-assisted selection or genetic engineering by introducing salt-tolerance genes. In this review, we have updated on mechanisms and genes which can help in transferring of the salt tolerance into high-yielding rice varieties. We have focused on the need for integrating phenotyping, genomics, metabolic profiling and phenomics into transgenic and breeding approaches to develop high-yielding as well as salt tolerant rice varieties.展开更多
Objective Cardiovascular complications contribute to postoperative morbidity and mortality in elderly hip fracture patients. Limited data are available regarding which preoperative risk factors predict cardiovascular ...Objective Cardiovascular complications contribute to postoperative morbidity and mortality in elderly hip fracture patients. Limited data are available regarding which preoperative risk factors predict cardiovascular course following hip fracture surgery (HFS). We used high sensitive troponin I (hs-TnI) assays and clinical parameters to identify preoperative risk factors associated with major adverse cardiac events (MACE) in elderly hip frac^u'e patients. Method From August 2014 to November 2016, 575 patients with hip fracture were enrolled in a retrospective, single-center registry. A total of 262 of these patients underwent HFS and hs-TnI assays. MACE was defined as postoperative all-cause deaths, heart failure (HF), new-onset atrial fibrillation (AF), myocardial infarction (MI) and cardiovascular re-hospitalization that occurred within 90 days postoperative. Results Of 262 HFS patients, MACE developed following HFS in 65 (24.8%). Patients with MACE were older and had higher rates of renal insufficiency, coronary artery disease, prior HF, low left ventricular ejection fraction and use of beta blockers; higher levels of hs-Tnl and N-terminal pro-brain natriuretic peptide (NT-proBNP) and higher revised cardiac risk index. A preoperative hs-TnI≥ 6.5 ng/L was associated with high risk of postoperative HF, new-onset AF and MACE. In multivariable analysis, pre-operative independent predictors for MACE were age 〉 80 years [adjusted hazard ratio (HR): 1.79, 95% confident interval (CI): 1.03-3.13, P = 0.04], left ventricular ejection fraction (LVEF) 〈 50% (adjusted HR: 3.17, 95% CI: 1.47-5.82, P 〈 0.01) and hs-TnI 〉 6.5 ng/L (adjusted HR: 3.75, 95% CI: 2.09~5.17, P 〈 0.01). Conclusion In elderly patients with hip fracture who undergo HFS, a preoperative assessment of hs-TnI may help the risk refinement of cardiovascular complications.展开更多
Three-dimensional (3D) printing is a novel process used to manufacture bone tissue engineered scaffolds. This process allows for easy control of the architecture at the micro structure. However, the scaffold propert...Three-dimensional (3D) printing is a novel process used to manufacture bone tissue engineered scaffolds. This process allows for easy control of the architecture at the micro structure. However, the scaffold properties are typically limited in terms of cellular activity at the scaffold surface due to the printed materials properties. In this study, we developed a polycaprolactone (PCL) blended with polyethylene glycol (PEG) 3D printed scaffold using a rapid prototyping system. The manufactured scaffolds were then washed out to form small pores on the surface in order to improve the scaffolds hydrophilicity. We analyzed the resultant material by using Scanning Electron Microscopy (SEM), water absorption, water contact angle, in vitro WST-1, and the Bradford assay. Additionally, cells incubated on the fabricated scaffolds were visualized by Confocal Laser Scanning Microscopy (CLSM). The developed scaffolds exhibited small pores on the strand surface which served to increase hydrophilicity as well as improve cellular proliferation and increase total protein content. Our findings suggest that the presence of small pores on the scaffolds can be used as an effective tool for improving implant cellular interaction. This research indicates that these modified scaffolds can be considered useful for bone tissue engineering applications to improve human health.展开更多
AIM:To clarify the short and long-term results and to prove the usefulness of endoscopic resection in type 3gastric neuroendocrine tumors(NETs).METHODS:Of the 119 type 3 gastric NETs diagnosed from January 1996 to Sep...AIM:To clarify the short and long-term results and to prove the usefulness of endoscopic resection in type 3gastric neuroendocrine tumors(NETs).METHODS:Of the 119 type 3 gastric NETs diagnosed from January 1996 to September 2011,50 patients treated with endoscopic resection were enrolled in this study.For endoscopic resection,endoscopic mucosal resection(EMR)or endoscopic submucosal dissection(ESD)was used.Therapeutic efficacy,complications,and follow-up results were evaluated retrospectively.RESULTS:EMR was performed in 41 cases and ESD in 9 cases.Pathologically complete resection was performed in 40 cases(80.0%)and incomplete resection specimens were observed in 10 cases(7 vs 3 patients in the EMR vs ESD group,P=0.249).Upon analysis of the incomplete resection group,lateral or vertical margin invasion was found in six cases(14.6%)in the EMR group and in one case in the ESD group(11.1%).Lymphovascular invasions were observed in two cases(22.2%)in the ESD group and in one case(2.4%)in the EMR group(P=0.080).During the follow-up period(43.73;13-60 mo),there was no evidence of tumor recurrence in either the pathologically complete resection group or the incomplete resection group.No recurrence was reported during follow-up.In addition,no mortality was reported in either the complete resection group or the incomplete resection group for the duration of the follow-up period.CONCLUSION:Less than 2 cm sized confined submucosal layer type 3 gastric NET with no evidence of lymphovascular invasion,endoscopic treatment could be considered at initial treatment.展开更多
Recently,ambient vibration test(AVT)is widely used tu estimate dynamic characteristics of large civil struc- tures.Dynamic characteristics ean be affected by various envirnnmental factors such as humidity,intensity of...Recently,ambient vibration test(AVT)is widely used tu estimate dynamic characteristics of large civil struc- tures.Dynamic characteristics ean be affected by various envirnnmental factors such as humidity,intensity of wind,and temperature.Besides these environmental conditions,tire mass of vehicles may change the measured valnes when traffic-in- duced vibration is used as a source of AVT tor bridges.The effect of vehicle mass on dynamic characteristics is investigated through traffic-induced vibration tests on three bridges;(1)three-span suspension bridge(128m+404m+128m),(2) five-span continuous steel box girder bridge(59m+3@ 95m+59m),(3)simply supported plate girder bridge(46m). Acceleration histories of each measurement location under normal traffic are recorded for 30 minutes at field.These recor- ded histories are divided into individual vibrations and are combined into two groups aceording to the level of vibration;one by heavy vehicles such as trucks and buses and the other by light vehicles such as passenger cars.Separate processing of the two groups of signals shows that,for the middle and long-span bridges,the difference can be hardly detected,but,for the short span bridges whose mass is relatively small,the measured natural frequencies can change up to 5.4%.展开更多
AIM: To clarify the mechanism underlying the anti-mutagenic and anti-cancer activities of Scorpio water extract (SWE). METHODS: Human hepatoma HepG2 cells were incubated with various concentrations of SWE. After 24-h ...AIM: To clarify the mechanism underlying the anti-mutagenic and anti-cancer activities of Scorpio water extract (SWE). METHODS: Human hepatoma HepG2 cells were incubated with various concentrations of SWE. After 24-h incubation, cytotoxicity and apoptosis evaluations were determined by MTT and DNA fragmentation assay, respectively. After treatment with SWE, mitochondrial membrane potential (MMP) was determined by measuring the retention of the dye 3,3'-dihexyloxacarbocyanine (DiOC6(3)) and the protein expression including cytochrome C and poly-(ADPribose) polymerase (PARP) were measured by Western blotting. Caspase-3 and -9 enzyme activities were measured using specific fluorescence dyes such as Ac-DEVD-AFC and Ac-LEHD-AFC. RESULTS: We found that treatment with SWE induced apoptosis as confirmed by discontinuous DNA fragmentation in cultured human hepatoma HepG2 cells. Our investigation also showed that SWE-induced apoptosis of HepG2 cells were associated with intracellular events including disruption of MMP, increased translocation of cytochrome C from mitochondria to cytosol, activation of caspase-3, and PARP. Pre-treatment of N-acetyl-Asp-Glu-Val-Asp-CHO (Ac-DEVD-CHO), a caspase-3 specific inhibitor, or cyclosporin A (CsA), an inhibitor of MMP disruption, completely abolished SWE-induced DNA fragmentation. CONCLUSION: These results suggest that SWE possibly causes mitochondrial damage, leading to cytochrome C release into cytosol and activation of caspases resulting in PARP cleavage and execution of apoptotic cell death in HepG2 cells. These results further suggest that Scorpio may be a valuable agent of therapeutic intervention of human hepatomas.展开更多
基金supported by the Basic Science Research Program of the National Research Foundation of Korea,which was funded by the Ministry of Science,ICT,and Future Planning(2018R1A2A2A15023219)a grant of the Korea Health Technology R&D Projea through the Korea Health Industry Development Institute(KHIDI)funded by the Ministry of Health&Welfare,Republic of Korea(HI20C0253)the Medical Research Centre(2017R1A5A2015395).
文摘Neuroinflammation is associated with neurodegenerative diseases,such as Alzheimer's disease,Parkinson's disease,ancamyotrophic lateral sclerosis.Microglia and astrocytes are key regulators of inflammatory responses in the central nervous system.The activation of microglia and astrocytes is heterogeneous and traditionally categorized as neurotoxi(M1-phenotype microglia and A1-phenotype astrocytes)or neuroprotective(M2-phenotype microglia and A2-phenotype astrocytes).However,this dichotomized classification may not reflect the various phenotypes of microgliaand astrocytes.The relationship between these activated glial cells is also very complicated,and the phenotypic distribution can change,based on the progression of neurodegenerative diseases.A better understanding of the rolesof microglia and astrocytes in neurodegenerative diseases is essential for developing effective therapies.In this review,we discuss the roles of inflammatory response in neurodegenerative diseases,focusing on the contributions of microglia and astrocytes and their relationship.In addition,we discuss biomarkers to measure neuroinflammation andstudies on therapeutic drugs that can modulate neuroinflammation.
文摘Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus (QTL) mapping and candidate gene analysis using whole- genome re-sequencing, we found that Oryza sativa Pseudo-Response Regulator37 (OsPRR37; hereafter PRR37) is respon- sible for the Early heading7-2 (EH7-2)/Heading date2 (Hd2) QTL which was identified from a cross of late-heading rice 'Milyang23 (M23)' and early-heading rice 'H143'. H143 contains a missense mutation of an invariantly conserved amino acid in the CCT (CONSTANS, CO-like, and TOC1) domain of PRR37 protein. In the world rice collection, different types of nonfunctional PRR37 alleles were found in many European and Asian rice cultivars. Notably, the japonica varieties harboring nonfunctional alleles of both Ghd7/Hd4 and PRR37/Hd2 flower extremely early under natural long-day condi- tions, and are adapted to the northernmost regions of rice cultivation, up to 53~ N latitude. Genetic analysis revealed that the effects of PRR37 and Ghd7 alleles on heading date are additive, and PRR37 down-regulates Hd3a expression to suppress flowering under long-day conditions. Our results demonstrate that natural variations in PRR37/Hd2 and GhdT/ Hd4 have contributed to the expansion of rice cultivation to temperate and cooler regions.
基金supported by Advanced Research Center Program(NRF-2013R1A5A1073861)through the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIP)contracted through Advanced Space Propulsion Research Center at Seoul National University
文摘A pintle injector is advantageous for throttling a liquid rocket engine and reducing engine weight. This study ex- plores the effects of momentum ratio and Weber number at various injection conditions on spray characteristics of the pintle injector for liquid-gas propellants. A liquid sheet is injected from a center pintle nozzle and it is broken by a gas jet from an annular gap. The pressure drops of propellants, and the pintle opening distance were consi- dered as control variables; using 0.1 -1.0 as a bar for the pressure drop of the liquid injection, a 0.01-4).2 bar for the pressure drop of gas jet and a 0.2 - 1.0 mm for the pintle opening distance. The discharge coefficient was de- creased linearly before the pintle opening distance of 0.75 mm and then, the coefficient was slightly increased. Spray images were captured by a CMOS camera with high resolution. Then, the shadow and reflected images were analyzed. Spray distributions were measured by a pattemator with an axial distance of 50 mm from a pintle tip. Finally, the spray half angles had an exponentially decreasing correlation as a momentum ratio divided by the Weber number. Also, the spray half angles from the spray distribution were underestimated compared to those measured from the captured images.
文摘The let-7 miRNAwas one of the first miRNAs discovered in the nematode, Caenorhabditis elegans, and its biological functions show a high level of evolutionary conservation from the nematode to the human. Unlike in C. elegans, higher animals have multiple isoforms of let-7 miRNAs; these isoforms share a consensus sequence called the 'seed sequence' and these isoforms are categorized into let-7 miRNA family. The expression of let-7 family is required for developmental timing and tumor suppressor function, but must be suppressed for the self-renewal of stem cells. Therefore, let-7 miRNA biogenesis must be carefully controlled. To generate a let-7 miRNA, a primary transcript is produced by RNA polymerase Ⅱ and then subsequently processed by Drosha/DGCR8, TUTase, and Dicer. Because dysregulation of let-7 processing is deleterious, biogenesis of let-7 is tightly regulated by cellular factors, such as the RNA binding proteins, LIN28A/B and DIS3L2. In this review, we discuss the biological functions and biogenesis of let-7 miRNAs, focusing on the molecular mechanisms of regulation of let-7 biogenesis in ver- tebrates, such as the mouse and the human.
基金Supported by the Regional Research Center Program of the Korean Ministry of Education & Human Resources Development through the Center for Healthcare Technology Development
文摘AIM: To clarify the mechanism underlying the antidiabetic activities of cortex cinnamomi extract (CCE). METHODS: To induce in vivo diabetes, mice were injected with streptozotocin (STZ) via a tail vein (100 mg STZ/kg body weight). To determine the effects of CCE, mice were administered CCE twice daily for 7 d by oral gavage starting 1 wk before the STZ injection. Blood glucose and plasma insulin concentration were measured as an index of diabetes. Also, to induce cytotoxicity of RINm5F cells, we treated with cytokines (IL-1β (2.0 ng/mL) and IFN-γ (100 U/mL)). Cell viability and nitric oxide production were measured colorimetrically. Inducible nitric oxide synthase (iNOS) mRNA and protein expression were determined by RT-PCR and Western blotting, respectively. The activation of NF-κβ was assayed by using gel mobility shift assays of nuclear extracts. RESULTS: Treatment of mice with STZ resulted in hyperglycemia and hypoinsulinemia, which was further evidenced by immunohistochemical staining of islets. However, the diabetogenic effects of STZ were completely prevented when mice were pretreated with CCE. The inhibitory effect of CCE on STZ-induced hyperglycemia was mediated through the suppression of iNOS expression. In rat insulinoma RINm5F cells,CCE completely protected against interleukin-1β and interferon-y-mediated cytotoxicity. Moreover, RINm5F cells incubated with CCE showed significant reductions in interleukin-1β and interferon-y-induced nitric oxide production and in iNOS mRNA and protein expression, and these findings correlated well with in vivo observations. CONCLUSION: The molecular mechanism by which CCE inhibits iNOS gene expression appears to involve the inhibition of NF-κβ activation, These results reveal the possible therapeutic value of CCE for the prevention of diabetes mellitus progression,
基金Project (10037273) supported by the Ministry of Knowledge Economy, Korea
文摘Diffusion bonding between aluminum and copper was performed by vacuum hot pressing at temperatures between 623 and 923 K through two thermal processes: hot compression under the deformation rate of 0.2 mrrdmin for 10 rain at pre-set temperatures, and additional pressing at 0.2 mm/min for 20 rain during furnace cooling. After analyzing interface, the feasible diffusion bonding temperature was suggested as 823 K. The three major intermetallic layers generated during diffusion bonding process were identified as AIECu, AlCu+AlaCu4 and Al4Cu9. Furthermore, local hardness values ofAlECU, AlCu+AlaCu4 and Al4Cu9 layers average at (4.97±0.05), (6.33±0.00) and (6.06±0.18) GPa, respectively.
基金Supported by Research Funds from Dong-A university
文摘AIM:To evaluate the potential usefulness of acoustic radiation force impulse (ARFI) images for evaluation of hepatocellular carcinomas (HCC)-associated radiofrequency ablation. METHODS:From January 2010 to June 2010,a total of 38 patients with HCC including recurred HCCs after RFA underwent ARFI elastography. The brightness of tumor was checked and the shear wave velocity was measure-d for the-quantification of stiffne-ss. According to theb-rightne-ss,the-tumors we-re-classifie-d as b-righte-r,samecolor and darker compared with adjacent parenchyma. Using the same methods,8 patients with recurred HCCs after RFA state were evaluated about the brightness compared with adjacent RFA ablation area. RESULTS:In the 38 patients with HCCs,20 (52.6%)were brighter than surrounding cirrhotic parenchyma. Another 13 (34.2%) were darker. The others (5 cases,13.2%) were seen as the same color as the adjacent liver parenchyma. Post-RFA lesions were darker than previous tumor and surrounding parenchyma in all 38 cases. However,recurred HCCs were brighter than the treated site in all 8 cases. CONCLUSION:Using ARFI technique is helpful for differential diagnosis in order to detect recurred HCCs more easily in patients with confusing status.
基金Supported by Inha University Research Grant and Korean Food and Drug Administration
文摘AIM: To compare the histopathologic features of intestinal tuberculosis (ITB) and Crohn’s disease (CD) and to identify whether polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) would be helpful for differential diagnosis between ITB and CD.METHODS: We selected 97 patients with established diagnoses (55 cases of ITB and 42 cases of CD) who underwent colonoscopic biopsies.Microscopic features of ITB and CD were reviewed,and eight pathologic parameters were evaluated.Nine cases of acid fast bacilli culture-positive specimens and 10 normal colonic tissue specimens were evaluated as the positive and negative control of the TB-PCR test,respectively.PCR assays were done using two commercial kits: kit <A> detected IS6110 and MPB64,and kit <B> detected IS6110 only;a manual in-house PCR method was also performed on formalin-fi xed,paraffi n-embedded colonoscopic biopsy specimens.RESULTS: Statistically significant differences were noted between ITB and CD with regard histopathologic criteria: size of granulomas (P = 0.000),giant cells (P = 0.015),caseation necrosis (P = 0.003),confluent granulomas (P = 0.001),discrete granulomas (P = 0.000),and granulomas with lymphoid cuffs (P = 0.037).However,29 cases (52.7%) of ITB showed less than fi ve kinds of pathologic parameters,resulting in confusion with CD.The sensitivities and specificities of the TB-PCR test by kit <A>,kit <B>,and the in-house PCR method were 88.9% and 100%,88.9% and 100%,and 66.7% and 100% in positive and negative controls,respectively.The PCR test done on endoscopic biopsy specimens of ITB and CD were signifi cantly different with kit <A> (P = 0.000) and kit <B> (P = 0.000).The sensitivities and specifi cities of TB-PCR were 45.5% and 88.1%,36.4% and 100%,and 5.8% and 100%,for kit <A> and kit <B> and inhouse PCR method on endoscopic biopsy specimens.Among the 29 cases of histopathologically confusing CD,10 cases assayed using kit <A> and 6 cases assayed using kit <B> were TB-PCR positive.A combination of histologic fi ndings and TB-PCR test
基金supported by the research grant funded by the national research foundation(NRF-2014R1A1A2059004)
文摘A differential-speed rolling(DSR) was applied to AZ31 magnesium alloy sample at different rolling temperatures of 473,523,573,and 623 K with 1-pass and 2-pass operations.The microstructural evolution and mechanical properties of the deformed samples were investigated.The rolling temperature was found to be an important parameter affecting the microstructural development.After DSR at 473 K,the microstructure was more homogeneous than that obtained after deformation by equal-speed rolling(ESR).The fully recrystallized microstructures were generated after DSR at 573 and 623 K.As to mechanical properties,the yield strength(YS) and ultimate tensile strength(UTS) decreased monotonously with increasing rolling temperature.In contrast,the elongation of the DSR-deformed samples was improved as the rolling temperature increased.The strain hardening exponent(n) calculated by Hollomon equation increased with increasing the rolling temperature,which would explain an increase in the uniform elongation.
基金supported by the National "863" Project of China
文摘A mobile molecular Doppler wind lidar at an eye-safe wavelength of 355 nm based on double-edge technique is being built in Hefei (China) for wind measurement from 10-to 40-km altitude. The structure of this lidar system is described. A triple Fabry-Perot etalon is employed as a frequency discriminator whose parameters are optimized. The receiver system is designed to achieve compactness and stability by putting in a standard 19-inch socket bench. Simulation results show that within the wind speed dynamic range of ±100 m/s, the horizontal wind errors due to noise are less than 1 m/s bdow 20-km altitude for 100-m vertical resolution, and less than 5.5 m/s from 20 km up to 40 km for 500-m vertical resolution with 400-mJ laser energy, 30-min temporal resolution, and a 45-cm aperture telescooe.
文摘Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long- distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we identified a T-DNA insertional mutant of Oryza sativa DNA BINDING WITH ONE FINGER 11 (OsDOF11), which is expressed in the vascular cells of photosynthetic organs and in various sink tissues. The osdofll mutant plants are semi-dwarf and have fewer tillers and smaller panicles as compared with wild-type (WT) plants. Although sucrose enhanced root elongation in young WT seedlings, this enhance- ment did not occur in osdof11 seedlings due to reduced sucrose uptake. Sugar transport rate analyses revealed that less sugar was transported in osdofll plants than in the WT. Expression of four Sucrose Transporter (SUT) genes-OsSUT1, OsSUT3, OsSUT4, and OsSUT5-as well as two Sugars Will Eventually be Exported Transporters (SWEET) genes, OsSWEETll and OsSWEET14, was altered in various organs of the mutant, including the leaves. Chromatin immunoprecipitation assays showed that OsDOFll directly binds the promoter regions of SUT1, OsSWEETll, and OsSWEET14, indicating that the expression of these transporters responsible for sucrose transport via apopiastic loading is coordinately controlled by OsDOFll. We also observed that osdofll mutant plants were less susceptible to infection byXanthomonas oryzae pathovar oryzae, suggesting that OsDOFll participates in sugar distribution during pathogenic in- vasion. Collectively, these results suggest that OsDOFll modulates sugar transport by regulating the expression of both SUT and SWEET genes in rice.
文摘Salt tolerance is an important constrain for rice, which is generally categorized as a typical glycophyte. Soil salinity is one of the major constraints affecting rice production worldwide, especially in the coastal areas. Susceptibility or tolerance of rice plants to high salinity is a coordinated action of multiple stress responsive genes, which also interacts with other components of stress signal transduction pathways. Salt tolerant varieties can be produced by marker-assisted selection or genetic engineering by introducing salt-tolerance genes. In this review, we have updated on mechanisms and genes which can help in transferring of the salt tolerance into high-yielding rice varieties. We have focused on the need for integrating phenotyping, genomics, metabolic profiling and phenomics into transgenic and breeding approaches to develop high-yielding as well as salt tolerant rice varieties.
文摘Objective Cardiovascular complications contribute to postoperative morbidity and mortality in elderly hip fracture patients. Limited data are available regarding which preoperative risk factors predict cardiovascular course following hip fracture surgery (HFS). We used high sensitive troponin I (hs-TnI) assays and clinical parameters to identify preoperative risk factors associated with major adverse cardiac events (MACE) in elderly hip frac^u'e patients. Method From August 2014 to November 2016, 575 patients with hip fracture were enrolled in a retrospective, single-center registry. A total of 262 of these patients underwent HFS and hs-TnI assays. MACE was defined as postoperative all-cause deaths, heart failure (HF), new-onset atrial fibrillation (AF), myocardial infarction (MI) and cardiovascular re-hospitalization that occurred within 90 days postoperative. Results Of 262 HFS patients, MACE developed following HFS in 65 (24.8%). Patients with MACE were older and had higher rates of renal insufficiency, coronary artery disease, prior HF, low left ventricular ejection fraction and use of beta blockers; higher levels of hs-Tnl and N-terminal pro-brain natriuretic peptide (NT-proBNP) and higher revised cardiac risk index. A preoperative hs-TnI≥ 6.5 ng/L was associated with high risk of postoperative HF, new-onset AF and MACE. In multivariable analysis, pre-operative independent predictors for MACE were age 〉 80 years [adjusted hazard ratio (HR): 1.79, 95% confident interval (CI): 1.03-3.13, P = 0.04], left ventricular ejection fraction (LVEF) 〈 50% (adjusted HR: 3.17, 95% CI: 1.47-5.82, P 〈 0.01) and hs-TnI 〉 6.5 ng/L (adjusted HR: 3.75, 95% CI: 2.09~5.17, P 〈 0.01). Conclusion In elderly patients with hip fracture who undergo HFS, a preoperative assessment of hs-TnI may help the risk refinement of cardiovascular complications.
文摘Three-dimensional (3D) printing is a novel process used to manufacture bone tissue engineered scaffolds. This process allows for easy control of the architecture at the micro structure. However, the scaffold properties are typically limited in terms of cellular activity at the scaffold surface due to the printed materials properties. In this study, we developed a polycaprolactone (PCL) blended with polyethylene glycol (PEG) 3D printed scaffold using a rapid prototyping system. The manufactured scaffolds were then washed out to form small pores on the surface in order to improve the scaffolds hydrophilicity. We analyzed the resultant material by using Scanning Electron Microscopy (SEM), water absorption, water contact angle, in vitro WST-1, and the Bradford assay. Additionally, cells incubated on the fabricated scaffolds were visualized by Confocal Laser Scanning Microscopy (CLSM). The developed scaffolds exhibited small pores on the strand surface which served to increase hydrophilicity as well as improve cellular proliferation and increase total protein content. Our findings suggest that the presence of small pores on the scaffolds can be used as an effective tool for improving implant cellular interaction. This research indicates that these modified scaffolds can be considered useful for bone tissue engineering applications to improve human health.
文摘AIM:To clarify the short and long-term results and to prove the usefulness of endoscopic resection in type 3gastric neuroendocrine tumors(NETs).METHODS:Of the 119 type 3 gastric NETs diagnosed from January 1996 to September 2011,50 patients treated with endoscopic resection were enrolled in this study.For endoscopic resection,endoscopic mucosal resection(EMR)or endoscopic submucosal dissection(ESD)was used.Therapeutic efficacy,complications,and follow-up results were evaluated retrospectively.RESULTS:EMR was performed in 41 cases and ESD in 9 cases.Pathologically complete resection was performed in 40 cases(80.0%)and incomplete resection specimens were observed in 10 cases(7 vs 3 patients in the EMR vs ESD group,P=0.249).Upon analysis of the incomplete resection group,lateral or vertical margin invasion was found in six cases(14.6%)in the EMR group and in one case in the ESD group(11.1%).Lymphovascular invasions were observed in two cases(22.2%)in the ESD group and in one case(2.4%)in the EMR group(P=0.080).During the follow-up period(43.73;13-60 mo),there was no evidence of tumor recurrence in either the pathologically complete resection group or the incomplete resection group.No recurrence was reported during follow-up.In addition,no mortality was reported in either the complete resection group or the incomplete resection group for the duration of the follow-up period.CONCLUSION:Less than 2 cm sized confined submucosal layer type 3 gastric NET with no evidence of lymphovascular invasion,endoscopic treatment could be considered at initial treatment.
基金the Ministry of Construction and Transportation,Korea Highway Corporation and Hyundai E&C Co.Ltd.under Project No.R&D/970003-2.
文摘Recently,ambient vibration test(AVT)is widely used tu estimate dynamic characteristics of large civil struc- tures.Dynamic characteristics ean be affected by various envirnnmental factors such as humidity,intensity of wind,and temperature.Besides these environmental conditions,tire mass of vehicles may change the measured valnes when traffic-in- duced vibration is used as a source of AVT tor bridges.The effect of vehicle mass on dynamic characteristics is investigated through traffic-induced vibration tests on three bridges;(1)three-span suspension bridge(128m+404m+128m),(2) five-span continuous steel box girder bridge(59m+3@ 95m+59m),(3)simply supported plate girder bridge(46m). Acceleration histories of each measurement location under normal traffic are recorded for 30 minutes at field.These recor- ded histories are divided into individual vibrations and are combined into two groups aceording to the level of vibration;one by heavy vehicles such as trucks and buses and the other by light vehicles such as passenger cars.Separate processing of the two groups of signals shows that,for the middle and long-span bridges,the difference can be hardly detected,but,for the short span bridges whose mass is relatively small,the measured natural frequencies can change up to 5.4%.
文摘AIM: To clarify the mechanism underlying the anti-mutagenic and anti-cancer activities of Scorpio water extract (SWE). METHODS: Human hepatoma HepG2 cells were incubated with various concentrations of SWE. After 24-h incubation, cytotoxicity and apoptosis evaluations were determined by MTT and DNA fragmentation assay, respectively. After treatment with SWE, mitochondrial membrane potential (MMP) was determined by measuring the retention of the dye 3,3'-dihexyloxacarbocyanine (DiOC6(3)) and the protein expression including cytochrome C and poly-(ADPribose) polymerase (PARP) were measured by Western blotting. Caspase-3 and -9 enzyme activities were measured using specific fluorescence dyes such as Ac-DEVD-AFC and Ac-LEHD-AFC. RESULTS: We found that treatment with SWE induced apoptosis as confirmed by discontinuous DNA fragmentation in cultured human hepatoma HepG2 cells. Our investigation also showed that SWE-induced apoptosis of HepG2 cells were associated with intracellular events including disruption of MMP, increased translocation of cytochrome C from mitochondria to cytosol, activation of caspase-3, and PARP. Pre-treatment of N-acetyl-Asp-Glu-Val-Asp-CHO (Ac-DEVD-CHO), a caspase-3 specific inhibitor, or cyclosporin A (CsA), an inhibitor of MMP disruption, completely abolished SWE-induced DNA fragmentation. CONCLUSION: These results suggest that SWE possibly causes mitochondrial damage, leading to cytochrome C release into cytosol and activation of caspases resulting in PARP cleavage and execution of apoptotic cell death in HepG2 cells. These results further suggest that Scorpio may be a valuable agent of therapeutic intervention of human hepatomas.