Dear Editor, In the past few years, the use of sequence-specific nucle- ases for efficient targeted mutagenesis has provided plant biologists with a powerful new approach for understanding gene function and developin...Dear Editor, In the past few years, the use of sequence-specific nucle- ases for efficient targeted mutagenesis has provided plant biologists with a powerful new approach for understanding gene function and developing new traits. These nucleases create DNA double-strand breaks at chromosomal targeted sites that are primarily repaired by the non-homologous end joining （NHEJ） or homologous recombination （HR） pathways. NHEJ is o^en imprecise and can introduce mutations at tar- get sites resulting in the loss of gene function. In contrast, HR uses a homologous DNA template for repair and can be employed to create site-specific sequence modifications or targeted insertions （Moynahan and Jasin, 2010）.展开更多
Augmented reality head-mounted displays(AR-HMDs)enable users to see real images of the outside world and visualize virtual information generated by a computer at any time and from any location,making them useful for v...Augmented reality head-mounted displays(AR-HMDs)enable users to see real images of the outside world and visualize virtual information generated by a computer at any time and from any location,making them useful for various applications.The manufacture of AR-HMDs combines the fields of optical engineering,optical materials,optical coating,precision manufacturing,electronic science,computer science,physiology,ergonomics,etc.This paper primarily focuses on the optical engineering of AR-HMDs.Optical combiners and display devices are used to combine real-world and virtual-world objects that are visible to the human eye.In this review,existing AR-HMD optical solutions employed for optical combiners are divided into three categories:optical solutions based on macro-,micro-,and nanooptics.The physical principles,optical structure,performance parameters,and manufacturing process of different types of AR-HMD optical solutions are subsequently analyzed.Moreover,their advantages and disadvantages are investigated and evaluated.In addition,the bottlenecks and future development trends in the case of AR-HMD optical solutions are discussed.展开更多
Sulfur poisoning of V_2O_5/BaSO_4–TiO_2（VBT）,V_2O_5/WO_3–TiO_2（VWT） and V_2O_5/BaSO_4–WO_3–TiO_2（VBWT） catalysts was performed in wet air at 350℃ for 3 hr,and activities for the selective catalytic reductio...Sulfur poisoning of V_2O_5/BaSO_4–TiO_2（VBT）,V_2O_5/WO_3–TiO_2（VWT） and V_2O_5/BaSO_4–WO_3–TiO_2（VBWT） catalysts was performed in wet air at 350℃ for 3 hr,and activities for the selective catalytic reduction of NO_x with NH_3 were evaluated for 200–500℃.The VBT catalyst showed higher NO_x conversions after sulfur poisoning than the other two catalysts.The introduction of barium sulfate contributed to strong acid sites for the as-received catalyst,and eliminated the redox cycle of active vanadium oxide to some extent,which resulted in a certain loss of activity.Readily decomposable sulfate species formed on VBT-S instead of inactive sulfates on VWT-S.These decomposable sulfates increased the number of strong acid sites significantly.Some sulfate species escaped during catalyst preparation and barium sulfate was reproduced during sulfur poisoning,which protects vanadia from sulfur oxide attachment to a great extent.Consequently,the VBT catalyst exhibited the best resistance to sulfur poisoning.展开更多
AIM: Choledocholithiasis is present in 5 to 10 percent of patients who have cholelithiasis. Tn the area of laparoscopic cholecystectomy (LC), laparoscopic common bile duct exploration (LCBDE) and intraoperative endosc...AIM: Choledocholithiasis is present in 5 to 10 percent of patients who have cholelithiasis. Tn the area of laparoscopic cholecystectomy (LC), laparoscopic common bile duct exploration (LCBDE) and intraoperative endoscopic sphincterotomy (IOES) have been used to treat choledocholithiasis. The purpose of this study was to compare the clinical outcomes and hospital costs of LCBDE with IOES.METHODS: Between November 1999 and October 2002,patients with choledocholithiasis undergoing LC plus LCBDE (Group A, n=45) were retrospectively compared to those undergoing LC plus IOES (Group B, n=57) at a single institution.RESULTS: Ductal stone clearance rates were equivalent for the two groups (88 % versus 89 %, P=0.436). The conversion rate was higher for Group B (8.8 % versus 4.4 %,P=0.381), as was the morbidity (12.3 % versus 6.7 %,P=0.336). There were no other significant differences between the two groups. The complications were mainly related to endoscopic sphincterotomy (ES), and the hospital costs were significantly increased in this subset of Group B (median, 23 910 versus 14 955 RMB yuan, P=0.03). Although hospital stay was longer in Group A (median, 7 versus 6 days,P=0.041), the patients in Group A had a significantly decreased cost of hospitalization compared with those in Group B (median, L1 362 versus 15 466 RMB yuan, P=0.000).CONCLUSION: The results demonstrate equivalent ductal stone clearance rates for the two groups. LCBDE management appears safer, and is associated with a significantly decreased hospital cost. The findings suggest LCBDE for choledocholithiasis is a better option.展开更多
Nanomaterials are increasingly used for biomedical applications; thus, it is important to understand their biological effects. Previous studies suggested that magnetic iron oxide nanoparticles （IONPs） have tissue-re...Nanomaterials are increasingly used for biomedical applications; thus, it is important to understand their biological effects. Previous studies suggested that magnetic iron oxide nanoparticles （IONPs） have tissue-repairing effects. In the present study, we explored cellular effects of IONPs in mesenchymal stem cells （MSCs） and identified the underlying molecular mechanisms. The results showed that our as-prepared IONPs were structurally stable in MSCs and promoted osteogenic differentiation of MSCs as whole particles. Moreover, at the molecular level, we compared the gene expression of MSCs with or without IONP exposure and showed that IONPs upregulated long noncoding RNA INZEB2, which is indispensable for maintaining osteogenesis by MSCs. Furthermore, overexpression of INZEB2 downregulated ZEB2, a factor necessary to repress BMP/Smad- dependent osteogenic transcription. We also demonstrated that the essential role of INZEB2 in osteogenic differentiation was ZEB2-dependent. In summary, we elucidated the molecular basis of IONPs＇ effects on MSCs; these findings may serve as a meaningful theoretical foundation for applications of stem cells to regenerative medicine.展开更多
Mulberry fruits with high concentrations of anthocyanins are favored by consumers because of their good taste,bright color,and high nutritional value.However,neither the regulatory mechanism controlling flavonoid bios...Mulberry fruits with high concentrations of anthocyanins are favored by consumers because of their good taste,bright color,and high nutritional value.However,neither the regulatory mechanism controlling flavonoid biosynthesis in mulberry nor the molecular basis of different mulberry fruit colors is fully understood.Here,we report that a flavonoid homeostasis network comprising activation and feedback regulation mechanisms determines mulberry fruit color.In vitro and in vivo assays showed that MYBA-bHLH3-TTG1 regulates the biosynthesis of anthocyanins,while TT2L1 and TT2L2 work with bHLH3 or GL3 and form a MYB-bHLH-WD40(MBW)complex with TTG1 to regulate proanthocyanidin(PA)synthesis.Functional and expression analyses showed that bHLH3 is a key regulator of the regulatory network controlling mulberry fruit coloration and that MYB4 is activated by MBW complexes and participates in negative feedback control of the regulatory network to balance the accumulation of anthocyanins and proanthocyanidins.Our research demonstrates that the interaction between bHLH3 and MYB4 in the homeostasis regulatory network ensures that the fruits accumulate desirable flavonoids and that this network is stable in pigmentrich mulberry fruits.However,the abnormal expression of bHLH3 disrupts the balance of the network and redirects flavonoid metabolic flux in pale-colored fruits,resulting in differences in the levels and proportions of anthocyanins,flavones,and flavonols among differently colored mulberry fruits(red,yellow,and white).The results of our study reveal the molecular basis of the diversity of mulberry fruit colors.展开更多
AIM:To describe the use of hand-assisted laparoscopic surg-ery(HALS) as an alternative to open conversion for complex gall-stone diseases, including Mirizzi syndrome (MS) and mimic MS. METHODS: Five patients with MS a...AIM:To describe the use of hand-assisted laparoscopic surg-ery(HALS) as an alternative to open conversion for complex gall-stone diseases, including Mirizzi syndrome (MS) and mimic MS. METHODS: Five patients with MS and mimic MS of 232 consecutive patients undergoing laparoscopic cholecyst-ectomies were analyzed. HALS without a hand-port device was performed as an alternative to open conversion if the anatomy was still unclear after the neck of the gallbladder was reached. RESULTS: HALS was performed on three patients with MS type I and 2 with mimic MS owing to an unclear or abnormal anatomy, or an unusual circumstance in which an impacted stone was squeezed out from the infundibulum or the aberrant cystic duct impossible with laparoscopic approach. The median operative time was 165 min (range, 115-190 min). The median hand-assisted time was 75 min (range, 65-100 min). The median postoperative stay was 4 d (range, 3-5 d). The postoperative course was uneventful, except for 1 patient complicated with a minor incision infection. CONCLUSION: HALS for MS type I and mimic MS is safe and feasible. It simplifies laparoscopic procedure, and can be used as an alternative to open conversion for complex gallstone diseases.展开更多
Human adenoviruses (HAdVs), especially HAdV-B3, -E4 and -B7, are associated with Acute Respiratory Disease in Chinese children, and occasionally in adults. In order to establish and document the profiles of the respir...Human adenoviruses (HAdVs), especially HAdV-B3, -E4 and -B7, are associated with Acute Respiratory Disease in Chinese children, and occasionally in adults. In order to establish and document the profiles of the respiratory adenovirus pathogen among children in Guangzhou, Southern China, a rapid, simple and practical method for identification and typing of respiratory adenoviruses was developed and evaluated. One pair of universal PCR primers was designed according to the conserved region of the hexon gene, which can detect not only HAdV-B3, -E4 and -B7, but also HAdV-B14, -F40 and -F41, with a specific 300bp PCR product. Three pairs of type-specific PCR primers were also designed according to the hypervariable regions of the hexon gene to type HAdV-B3, -E4 and -B7 by three independent PCR reactions, making it easy to optimize the PCR conditions. By using this method, one hundred throat swab specimens collected during Oct 2010 to Dec 2011 and suspected of being positive for adenoviral infection were identified and typed for adenoviruses. Of these samples, fifty-five were adenovirus-positive. The most common HAdV type was HAdV-B3, identified in 92.7% of samples, which is not only consistent with the data reported in 2004-2006, but also consistent with the recent report in Hangzhou, eastern China, indicating that HAdV-B3 has been circulating in Guangzhou, and maybe in eastern China, for many years. The method for the respiratory adenovirus identification and typing we developed is rapid, simple and practical, which has a potential in the real-time surveillance of circulating adenovirus strains and also to provide etiological evidence for the adenovirus-relative disease control and prevention in China.展开更多
Molecular oxygen(O2)is essential for most biological reactions in mammalian cells.When the intracellular oxygen content decreases,it is called hypoxia.The process of hypoxia is linked to several biological processes,i...Molecular oxygen(O2)is essential for most biological reactions in mammalian cells.When the intracellular oxygen content decreases,it is called hypoxia.The process of hypoxia is linked to several biological processes,including pathogenic microbe infection,metabolic adaptation,cancer,acute and chronic diseases,and other stress responses.The mechanism underlying cells respond to oxygen changes to mediate subsequent signal response is the central question during hypoxia.Hypoxia-inducible factors(HIFs)sense hypoxia to regulate the expressions of a series of downstream genes expression,which participate in multiple processes including cell metabolism,cell growth/death,cell proliferation,glycolysis,immune response,microbe infection,tumorigenesis,and metastasis.Importantly,hypoxia signaling also interacts with other cellular pathways,such as phosphoinositide 3-kinase(PI3K)-mammalian target of rapamycin(mTOR)signaling,nuclear factor kappa-B(NF-κB)pathway,extracellular signal-regulated kinases(ERK)signaling,and endoplasmic reticulum(ER)stress.This paper systematically reviews the mechanisms of hypoxia signaling activation,the control of HIF signaling,and the function of HIF signaling in human health and diseases.In addition,the therapeutic targets involved in HIF signaling to balance health and diseases are summarized and highlighted,which would provide novel strategies for the design and development of therapeutic drugs.展开更多
Breakthroughs in the generation of programmable sequence-specific nucleases (SSNs), such as zinc finger nucleases (ZFNs),TAL effector nucleases (TALENs) and the RNA-directed nuclease CRISPR-associated protein 9 (Cas9)...Breakthroughs in the generation of programmable sequence-specific nucleases (SSNs), such as zinc finger nucleases (ZFNs),TAL effector nucleases (TALENs) and the RNA-directed nuclease CRISPR-associated protein 9 (Cas9), have greatly increased the ease of plant genome engineering (Voytas, 2013; Malzahn et al.,2017). Programmable SSNs introduce a DNA double-strand break展开更多
SIRT1 plays an important role in adipogenesis, but how SIRT1 is regulated in adipogenesis is largely unknown. In this study, we show that both SIRT1 protein and mRNA levels were increased along with CCAAT/enhancer-bin...SIRT1 plays an important role in adipogenesis, but how SIRT1 is regulated in adipogenesis is largely unknown. In this study, we show that both SIRT1 protein and mRNA levels were increased along with CCAAT/enhancer-binding protein a （C/EBPa） during adipocyte differentiation. C/EBPa, but not C/EBPap30, activated SIRT1 promoter in both HeLa cells and 3T3-L1 preadipocytes. Furthermore, C/EBPa upregulated SIRT1 mRNA and protein levels in HeLa cells and increased SIRT1 expression in a p53-independent manner in Soas2 cells. In preadipocytes, ectopic expression of C/EBPa upregulated SIRT1 protein level and knockdown of C/EBPa led to the decrease of SIRTI pro- tein level. Moreover, by promoter deletion analysis, gel shift assay and chromatin immunoprecipitation, we found that C/EBPa bound to the SIRT1 promoter at a consensus C/EBPα binding site. These data demonstrate that C/ EBPα regulates SIRT1 expression during adipogenesis by directly binding to the SIRT1 promoter.展开更多
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to dire...Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.展开更多
Adakitic rocks are intermediate-acid magmatic rocks characterized by enrichment in light rare-earth elements,depletion in heavy rare-earth elements,positive to negligible Eu and Sr anomalies,and high La/Yb and Sr/Y ra...Adakitic rocks are intermediate-acid magmatic rocks characterized by enrichment in light rare-earth elements,depletion in heavy rare-earth elements,positive to negligible Eu and Sr anomalies,and high La/Yb and Sr/Y ratios.Cenozoic adakitic rocks generated by partial melting of subducted oceanic crust(slab)under eclogite-facies conditions(i.e.,the original definition of“adakite”)occur mainly in Pacific Rim volcanic arcs(intra-oceanic,continental,and continental-margin island arcs),whereas those generated by partial melting of thickened lower crust occur mainly in Tethyan Tibetan collisional orogens.In volcanic arcs,adakitic melts derived from the melting of subducted oceanic crust metasomatize the mantle wedge to form a unique rock suite comprising adakite-adakite-type high-Mg andesite-Piip-type high-Mg andesite-Nb-rich basalt-boninite.This suite differs from the basalt-andesite-dacite-rhyolite suite formed from mantle wedge metasomatized by fluids derived from subducted oceanic crust.Previously published data indicate that partial melting of mafic rocks can generate adakitic magmas under pressure,temperature,and hydrous conditions of 1.2-3.0 GPa,800-1000℃,and 1.5-6.0 wt.%H_(2)O,respectively,leaving residual minerals of garnet and rutile with little or no plagioclase.Cenozoic Au and Cu deposits occur proximally to adakitic rocks,with host rocks of some deposits actually being adakitic rocks.Adakitic rocks thus have important implications for both deep-Earth dynamics and Cu-Au mineralization/exploration.Although studies of Cenozoic adakitic rocks have made many important advances,there remain weaknesses in some important areas such as their tectonic settings,petrogenesis,magma sources,melt-mantle interactions of pre-Cenozoic adakitic rocks,and their relationship with the onset of plate tectonics and crustal growth.Future research directions are likely to involve(1)the generation of adakitic magmas by experimental simulations of partial melting of different types of rock(including intermediate-acid rocks)and m展开更多
Compactness and light weight,large exit pupil diameter and distance,small distortion for virtual image,and see-through light paths are pivotal factors to achieve a better,wearable experience of optical see-through hea...Compactness and light weight,large exit pupil diameter and distance,small distortion for virtual image,and see-through light paths are pivotal factors to achieve a better,wearable experience of optical see-through headmounted displays(OST-HMDs).In addition,light efficiency of the virtual image light path is an important factor for heat dissipation in HMD devices.This paper presents a new type of OST-HMD optical system that includes three wedge-shaped freeform prisms and two symmetric lenses.Based on a 0.71 in.microdisplay,an OST-HMD prototype with a diagonal field of view(FOV)of 45.3°,an F-number(F/#)of 1.8,an exit pupil size of 12 mm×8 mm,and an eye relief of 18 mm is demonstrated.The maximum value of distortion of the final system is 0.6%and 0.4%for virtual image and see-through light path,respectively.The overall dimension of the optical system per eye is no larger than 30 mm(width)×40 mm(height)×14 mm(thickness),and the weight of the optical module including lenses,holder,and microdisplay is 12.8 g.The light efficiency of the virtual image light path is up to 50%higher than those of other OST-HMD optical solutions.展开更多
Potassium-ion batteries(KIBs)are a potential candidate to lithium-ion batteries(LIBs)but possess unsatisfactory capacity and rate properties.Herein,the metallic cobalt selenide quantum dots(Co0.85Se-QDs)encapsulated i...Potassium-ion batteries(KIBs)are a potential candidate to lithium-ion batteries(LIBs)but possess unsatisfactory capacity and rate properties.Herein,the metallic cobalt selenide quantum dots(Co0.85Se-QDs)encapsulated in mesoporous carbon matrix were designed via a direct hydrothermal method.Specifically,the cobalt selenide/carbon composite(Co0.85Se-QDs/C)possesses tertiary hierarchical structure,which is the primary quantum dots,the secondary petals flake,and the tertiary hollow micropolyhedron framework.Co0.85Se-QDs are homogenously embedded into the carbon petals flake,which constitute the hollow polyhedral framework.This unique structure can take the advantages of both nanoscale and microscale features:Co0.85Se-QDs can expand in a multidimensional and ductile carbon matrix and reduce the K-intercalation stress in particle dimensions;the micropetals can restrain the agglomeration of active materials and promote the transportation of potassium ion and electron.In addition,the hollow carbon framework buffers volume expansion,maintains the structural integrity,and increases the electronic conductivity.Benefiting from this tertiary hierarchical structure,outstanding K-storage performance(402 mAh g?1 after 100 cycles at 50 mA g?1)is obtained when Co0.85Se-QDs/C is used as KIBs anode.More importantly,the selenization process in this work is newly reported and can be generally extended to prepare other quantum dots encapsulated in edge-limited frameworks for excellent energy storage.展开更多
文摘Dear Editor, In the past few years, the use of sequence-specific nucle- ases for efficient targeted mutagenesis has provided plant biologists with a powerful new approach for understanding gene function and developing new traits. These nucleases create DNA double-strand breaks at chromosomal targeted sites that are primarily repaired by the non-homologous end joining （NHEJ） or homologous recombination （HR） pathways. NHEJ is o^en imprecise and can introduce mutations at tar- get sites resulting in the loss of gene function. In contrast, HR uses a homologous DNA template for repair and can be employed to create site-specific sequence modifications or targeted insertions （Moynahan and Jasin, 2010）.
文摘Augmented reality head-mounted displays(AR-HMDs)enable users to see real images of the outside world and visualize virtual information generated by a computer at any time and from any location,making them useful for various applications.The manufacture of AR-HMDs combines the fields of optical engineering,optical materials,optical coating,precision manufacturing,electronic science,computer science,physiology,ergonomics,etc.This paper primarily focuses on the optical engineering of AR-HMDs.Optical combiners and display devices are used to combine real-world and virtual-world objects that are visible to the human eye.In this review,existing AR-HMD optical solutions employed for optical combiners are divided into three categories:optical solutions based on macro-,micro-,and nanooptics.The physical principles,optical structure,performance parameters,and manufacturing process of different types of AR-HMD optical solutions are subsequently analyzed.Moreover,their advantages and disadvantages are investigated and evaluated.In addition,the bottlenecks and future development trends in the case of AR-HMD optical solutions are discussed.
基金the financial support from projects of the Ministry of Science and Technology,China(Nos.2015AA034603,2016YFC0205200)the Science and Technology Department of Zhejiang Province,China(No.2015C31015)
文摘Sulfur poisoning of V_2O_5/BaSO_4–TiO_2（VBT）,V_2O_5/WO_3–TiO_2（VWT） and V_2O_5/BaSO_4–WO_3–TiO_2（VBWT） catalysts was performed in wet air at 350℃ for 3 hr,and activities for the selective catalytic reduction of NO_x with NH_3 were evaluated for 200–500℃.The VBT catalyst showed higher NO_x conversions after sulfur poisoning than the other two catalysts.The introduction of barium sulfate contributed to strong acid sites for the as-received catalyst,and eliminated the redox cycle of active vanadium oxide to some extent,which resulted in a certain loss of activity.Readily decomposable sulfate species formed on VBT-S instead of inactive sulfates on VWT-S.These decomposable sulfates increased the number of strong acid sites significantly.Some sulfate species escaped during catalyst preparation and barium sulfate was reproduced during sulfur poisoning,which protects vanadia from sulfur oxide attachment to a great extent.Consequently,the VBT catalyst exhibited the best resistance to sulfur poisoning.
文摘AIM: Choledocholithiasis is present in 5 to 10 percent of patients who have cholelithiasis. Tn the area of laparoscopic cholecystectomy (LC), laparoscopic common bile duct exploration (LCBDE) and intraoperative endoscopic sphincterotomy (IOES) have been used to treat choledocholithiasis. The purpose of this study was to compare the clinical outcomes and hospital costs of LCBDE with IOES.METHODS: Between November 1999 and October 2002,patients with choledocholithiasis undergoing LC plus LCBDE (Group A, n=45) were retrospectively compared to those undergoing LC plus IOES (Group B, n=57) at a single institution.RESULTS: Ductal stone clearance rates were equivalent for the two groups (88 % versus 89 %, P=0.436). The conversion rate was higher for Group B (8.8 % versus 4.4 %,P=0.381), as was the morbidity (12.3 % versus 6.7 %,P=0.336). There were no other significant differences between the two groups. The complications were mainly related to endoscopic sphincterotomy (ES), and the hospital costs were significantly increased in this subset of Group B (median, 23 910 versus 14 955 RMB yuan, P=0.03). Although hospital stay was longer in Group A (median, 7 versus 6 days,P=0.041), the patients in Group A had a significantly decreased cost of hospitalization compared with those in Group B (median, L1 362 versus 15 466 RMB yuan, P=0.000).CONCLUSION: The results demonstrate equivalent ductal stone clearance rates for the two groups. LCBDE management appears safer, and is associated with a significantly decreased hospital cost. The findings suggest LCBDE for choledocholithiasis is a better option.
文摘Nanomaterials are increasingly used for biomedical applications; thus, it is important to understand their biological effects. Previous studies suggested that magnetic iron oxide nanoparticles （IONPs） have tissue-repairing effects. In the present study, we explored cellular effects of IONPs in mesenchymal stem cells （MSCs） and identified the underlying molecular mechanisms. The results showed that our as-prepared IONPs were structurally stable in MSCs and promoted osteogenic differentiation of MSCs as whole particles. Moreover, at the molecular level, we compared the gene expression of MSCs with or without IONP exposure and showed that IONPs upregulated long noncoding RNA INZEB2, which is indispensable for maintaining osteogenesis by MSCs. Furthermore, overexpression of INZEB2 downregulated ZEB2, a factor necessary to repress BMP/Smad- dependent osteogenic transcription. We also demonstrated that the essential role of INZEB2 in osteogenic differentiation was ZEB2-dependent. In summary, we elucidated the molecular basis of IONPs＇ effects on MSCs; these findings may serve as a meaningful theoretical foundation for applications of stem cells to regenerative medicine.
基金funded by the“111”Project(No.B12006)the National Key Research and Development Program(No.2018YFD1000602)+3 种基金the Special Fund for Agro-scientific Research in the Public Interest of China(No.201403064)the Natural Science Foundation of China(No.31572323)Fundamental Research Funds for the Central Universities(No.SW118040)the Chongqing Research Program of Basic Research and Frontier Technology(No.cstc2018jcyjAX0407).
文摘Mulberry fruits with high concentrations of anthocyanins are favored by consumers because of their good taste,bright color,and high nutritional value.However,neither the regulatory mechanism controlling flavonoid biosynthesis in mulberry nor the molecular basis of different mulberry fruit colors is fully understood.Here,we report that a flavonoid homeostasis network comprising activation and feedback regulation mechanisms determines mulberry fruit color.In vitro and in vivo assays showed that MYBA-bHLH3-TTG1 regulates the biosynthesis of anthocyanins,while TT2L1 and TT2L2 work with bHLH3 or GL3 and form a MYB-bHLH-WD40(MBW)complex with TTG1 to regulate proanthocyanidin(PA)synthesis.Functional and expression analyses showed that bHLH3 is a key regulator of the regulatory network controlling mulberry fruit coloration and that MYB4 is activated by MBW complexes and participates in negative feedback control of the regulatory network to balance the accumulation of anthocyanins and proanthocyanidins.Our research demonstrates that the interaction between bHLH3 and MYB4 in the homeostasis regulatory network ensures that the fruits accumulate desirable flavonoids and that this network is stable in pigmentrich mulberry fruits.However,the abnormal expression of bHLH3 disrupts the balance of the network and redirects flavonoid metabolic flux in pale-colored fruits,resulting in differences in the levels and proportions of anthocyanins,flavones,and flavonols among differently colored mulberry fruits(red,yellow,and white).The results of our study reveal the molecular basis of the diversity of mulberry fruit colors.
文摘AIM:To describe the use of hand-assisted laparoscopic surg-ery(HALS) as an alternative to open conversion for complex gall-stone diseases, including Mirizzi syndrome (MS) and mimic MS. METHODS: Five patients with MS and mimic MS of 232 consecutive patients undergoing laparoscopic cholecyst-ectomies were analyzed. HALS without a hand-port device was performed as an alternative to open conversion if the anatomy was still unclear after the neck of the gallbladder was reached. RESULTS: HALS was performed on three patients with MS type I and 2 with mimic MS owing to an unclear or abnormal anatomy, or an unusual circumstance in which an impacted stone was squeezed out from the infundibulum or the aberrant cystic duct impossible with laparoscopic approach. The median operative time was 165 min (range, 115-190 min). The median hand-assisted time was 75 min (range, 65-100 min). The median postoperative stay was 4 d (range, 3-5 d). The postoperative course was uneventful, except for 1 patient complicated with a minor incision infection. CONCLUSION: HALS for MS type I and mimic MS is safe and feasible. It simplifies laparoscopic procedure, and can be used as an alternative to open conversion for complex gallstone diseases.
基金supported by National Natural Science Foundation of China (31100133)Natural Science Foundation of Guangdong Province (S2012010009261)+2 种基金Guangdong College Students' Innovative Experimental Project(1212111023)Extracurricular Research Activities of Southern Medical University (2010kw076)School of Public Health and Tropical Medicine (GWXS20110102)
文摘Human adenoviruses (HAdVs), especially HAdV-B3, -E4 and -B7, are associated with Acute Respiratory Disease in Chinese children, and occasionally in adults. In order to establish and document the profiles of the respiratory adenovirus pathogen among children in Guangzhou, Southern China, a rapid, simple and practical method for identification and typing of respiratory adenoviruses was developed and evaluated. One pair of universal PCR primers was designed according to the conserved region of the hexon gene, which can detect not only HAdV-B3, -E4 and -B7, but also HAdV-B14, -F40 and -F41, with a specific 300bp PCR product. Three pairs of type-specific PCR primers were also designed according to the hypervariable regions of the hexon gene to type HAdV-B3, -E4 and -B7 by three independent PCR reactions, making it easy to optimize the PCR conditions. By using this method, one hundred throat swab specimens collected during Oct 2010 to Dec 2011 and suspected of being positive for adenoviral infection were identified and typed for adenoviruses. Of these samples, fifty-five were adenovirus-positive. The most common HAdV type was HAdV-B3, identified in 92.7% of samples, which is not only consistent with the data reported in 2004-2006, but also consistent with the recent report in Hangzhou, eastern China, indicating that HAdV-B3 has been circulating in Guangzhou, and maybe in eastern China, for many years. The method for the respiratory adenovirus identification and typing we developed is rapid, simple and practical, which has a potential in the real-time surveillance of circulating adenovirus strains and also to provide etiological evidence for the adenovirus-relative disease control and prevention in China.
基金sponsored by National Natural Science Foundation of China(81730061 to J.W.,32070148 to Z.L.,and 32100738 to P.W.)China Postdoctoral Science Foundation(2021M691246 to M.T.).
文摘Molecular oxygen(O2)is essential for most biological reactions in mammalian cells.When the intracellular oxygen content decreases,it is called hypoxia.The process of hypoxia is linked to several biological processes,including pathogenic microbe infection,metabolic adaptation,cancer,acute and chronic diseases,and other stress responses.The mechanism underlying cells respond to oxygen changes to mediate subsequent signal response is the central question during hypoxia.Hypoxia-inducible factors(HIFs)sense hypoxia to regulate the expressions of a series of downstream genes expression,which participate in multiple processes including cell metabolism,cell growth/death,cell proliferation,glycolysis,immune response,microbe infection,tumorigenesis,and metastasis.Importantly,hypoxia signaling also interacts with other cellular pathways,such as phosphoinositide 3-kinase(PI3K)-mammalian target of rapamycin(mTOR)signaling,nuclear factor kappa-B(NF-κB)pathway,extracellular signal-regulated kinases(ERK)signaling,and endoplasmic reticulum(ER)stress.This paper systematically reviews the mechanisms of hypoxia signaling activation,the control of HIF signaling,and the function of HIF signaling in human health and diseases.In addition,the therapeutic targets involved in HIF signaling to balance health and diseases are summarized and highlighted,which would provide novel strategies for the design and development of therapeutic drugs.
基金supported by a Collaborative Funding Grant from North Carolina Biotechnology Center and Syngenta Biotechnology (2016-CFG-8003)startup funds provided by East Carolina University and University of Maryland to Y.Q.a grant from the National Science Foundation (IOS-1339209)
文摘Breakthroughs in the generation of programmable sequence-specific nucleases (SSNs), such as zinc finger nucleases (ZFNs),TAL effector nucleases (TALENs) and the RNA-directed nuclease CRISPR-associated protein 9 (Cas9), have greatly increased the ease of plant genome engineering (Voytas, 2013; Malzahn et al.,2017). Programmable SSNs introduce a DNA double-strand break
文摘SIRT1 plays an important role in adipogenesis, but how SIRT1 is regulated in adipogenesis is largely unknown. In this study, we show that both SIRT1 protein and mRNA levels were increased along with CCAAT/enhancer-binding protein a （C/EBPa） during adipocyte differentiation. C/EBPa, but not C/EBPap30, activated SIRT1 promoter in both HeLa cells and 3T3-L1 preadipocytes. Furthermore, C/EBPa upregulated SIRT1 mRNA and protein levels in HeLa cells and increased SIRT1 expression in a p53-independent manner in Soas2 cells. In preadipocytes, ectopic expression of C/EBPa upregulated SIRT1 protein level and knockdown of C/EBPa led to the decrease of SIRTI pro- tein level. Moreover, by promoter deletion analysis, gel shift assay and chromatin immunoprecipitation, we found that C/EBPa bound to the SIRT1 promoter at a consensus C/EBPα binding site. These data demonstrate that C/ EBPα regulates SIRT1 expression during adipogenesis by directly binding to the SIRT1 promoter.
基金supported by the National Natural Science Foundation of China(Grant Nos.11490560 and 11321064)the National Basic Research Program of China(Grant No.2013CB834406)
文摘Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.
基金the National Natural Science Foundation of China(Grant Nos.41630208 and 91855215)the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(Grant No.2019QZKK0702)+2 种基金the National Key R&D Program of China(Grant No.2016YFC0600407)the Strategic Priority Research Program(A)of the Chinese Academy of Sciences(Grant No.XDA2007030402),the Key Program of the Chinese Academy of Sciences(Grant No.QYZDJ-SSWDQC026)the Key Program of Guangzhou City(Grant No.201707020032).
文摘Adakitic rocks are intermediate-acid magmatic rocks characterized by enrichment in light rare-earth elements,depletion in heavy rare-earth elements,positive to negligible Eu and Sr anomalies,and high La/Yb and Sr/Y ratios.Cenozoic adakitic rocks generated by partial melting of subducted oceanic crust(slab)under eclogite-facies conditions(i.e.,the original definition of“adakite”)occur mainly in Pacific Rim volcanic arcs(intra-oceanic,continental,and continental-margin island arcs),whereas those generated by partial melting of thickened lower crust occur mainly in Tethyan Tibetan collisional orogens.In volcanic arcs,adakitic melts derived from the melting of subducted oceanic crust metasomatize the mantle wedge to form a unique rock suite comprising adakite-adakite-type high-Mg andesite-Piip-type high-Mg andesite-Nb-rich basalt-boninite.This suite differs from the basalt-andesite-dacite-rhyolite suite formed from mantle wedge metasomatized by fluids derived from subducted oceanic crust.Previously published data indicate that partial melting of mafic rocks can generate adakitic magmas under pressure,temperature,and hydrous conditions of 1.2-3.0 GPa,800-1000℃,and 1.5-6.0 wt.%H_(2)O,respectively,leaving residual minerals of garnet and rutile with little or no plagioclase.Cenozoic Au and Cu deposits occur proximally to adakitic rocks,with host rocks of some deposits actually being adakitic rocks.Adakitic rocks thus have important implications for both deep-Earth dynamics and Cu-Au mineralization/exploration.Although studies of Cenozoic adakitic rocks have made many important advances,there remain weaknesses in some important areas such as their tectonic settings,petrogenesis,magma sources,melt-mantle interactions of pre-Cenozoic adakitic rocks,and their relationship with the onset of plate tectonics and crustal growth.Future research directions are likely to involve(1)the generation of adakitic magmas by experimental simulations of partial melting of different types of rock(including intermediate-acid rocks)and m
基金National Key Research and Development Program of China(2017YFA0701200)National Natural Science Foundation of China(61822502)Beijing Municipal Science Technology Commission(Z201100004020011)。
文摘Compactness and light weight,large exit pupil diameter and distance,small distortion for virtual image,and see-through light paths are pivotal factors to achieve a better,wearable experience of optical see-through headmounted displays(OST-HMDs).In addition,light efficiency of the virtual image light path is an important factor for heat dissipation in HMD devices.This paper presents a new type of OST-HMD optical system that includes three wedge-shaped freeform prisms and two symmetric lenses.Based on a 0.71 in.microdisplay,an OST-HMD prototype with a diagonal field of view(FOV)of 45.3°,an F-number(F/#)of 1.8,an exit pupil size of 12 mm×8 mm,and an eye relief of 18 mm is demonstrated.The maximum value of distortion of the final system is 0.6%and 0.4%for virtual image and see-through light path,respectively.The overall dimension of the optical system per eye is no larger than 30 mm(width)×40 mm(height)×14 mm(thickness),and the weight of the optical module including lenses,holder,and microdisplay is 12.8 g.The light efficiency of the virtual image light path is up to 50%higher than those of other OST-HMD optical solutions.
基金financially supported by Beijing Natural Science Foundation(No.2192034)China Postdoctoral Science Foundation(No.2018M631335)National Key R&D Program of China(No.2018YFB0905600).
文摘Potassium-ion batteries(KIBs)are a potential candidate to lithium-ion batteries(LIBs)but possess unsatisfactory capacity and rate properties.Herein,the metallic cobalt selenide quantum dots(Co0.85Se-QDs)encapsulated in mesoporous carbon matrix were designed via a direct hydrothermal method.Specifically,the cobalt selenide/carbon composite(Co0.85Se-QDs/C)possesses tertiary hierarchical structure,which is the primary quantum dots,the secondary petals flake,and the tertiary hollow micropolyhedron framework.Co0.85Se-QDs are homogenously embedded into the carbon petals flake,which constitute the hollow polyhedral framework.This unique structure can take the advantages of both nanoscale and microscale features:Co0.85Se-QDs can expand in a multidimensional and ductile carbon matrix and reduce the K-intercalation stress in particle dimensions;the micropetals can restrain the agglomeration of active materials and promote the transportation of potassium ion and electron.In addition,the hollow carbon framework buffers volume expansion,maintains the structural integrity,and increases the electronic conductivity.Benefiting from this tertiary hierarchical structure,outstanding K-storage performance(402 mAh g?1 after 100 cycles at 50 mA g?1)is obtained when Co0.85Se-QDs/C is used as KIBs anode.More importantly,the selenization process in this work is newly reported and can be generally extended to prepare other quantum dots encapsulated in edge-limited frameworks for excellent energy storage.
