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Calcium-fortified fresh milk ameliorates postmenopausal osteoporosis via regulation of bone metabolism and gut microbiota in ovariectomized rats 被引量:1
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作者 Qishan Wang Bin Liu +5 位作者 Xianping Li Junying Zhao Zongshen Zhang Weicang Qiao Xinyue Wei Lijun Chen 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1258-1270,共13页
The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorat... The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorating postmenopausal osteoporosis in a rat model established using bilateral ovariectomy.After 3 months of FM(containing vitamin D,and casein phosphopeptides,1000 mg Ca/100 g)or control milk(110 mg Ca/100 g milk)supplementation,bone changes were assessed using dual-energy X-ray absorptiometry,microcomputed tomography,and bone biomechanical testing.The results revealed that FM can regulate bone metabolism and gut microbiota composition,which act on bone metabolism through pathways associated with steroid hormone biosynthesis,relaxin signaling,serotonergic synapse,and unsaturated fatty acid biosynthesis.Furthermore,FM administration significantly increased bone mineral content and density in the lumbar spine and femur,as well as femoral compressive strength,while improving femoral trabecular bone parameters and microarchitecture.Mechanistically,we found that the effects may be due to increased levels of estrogen,bone formation marker osteocalcin,and procollagen typeⅠN-propeptide,and decreased expression of the bone resorption marker C-telopiptide and tartrate-resistant acid phosphatase 5b.Overall,the findings suggest that FM is a potential alternative therapeutic option for ameliorating postmenopausal osteoporosis. 展开更多
关键词 Dairy products calcium Vitamin D Bone turnover markers Gut microbiota Postmenopausal osteoporosis
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Regulation of specific abnormal calcium signals in the hippocampal CA1 and primary cortex M1 alleviates the progression of temporal lobe epilepsy
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作者 Feng Chen Xi Dong +11 位作者 Zhenhuan Wang Tongrui Wu Liangpeng Wei Yuanyuan Li Kai Zhang Zengguang Ma Chao Tian Jing Li Jingyu Zhao Wei Zhang Aili Liu Hui Shen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期425-433,共9页
Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence rate.The pathogenesis of temporal lobe epilepsy is complex and... Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence rate.The pathogenesis of temporal lobe epilepsy is complex and is not fully understood.Intracellular calcium dynamics have been implicated in temporal lobe epilepsy.However,the effect of fluctuating calcium activity in CA1 pyramidal neurons on temporal lobe epilepsy is unknown,and no longitudinal studies have investigated calcium activity in pyramidal neurons in the hippocampal CA1 and primary motor cortex M1 of freely moving mice.In this study,we used a multichannel fiber photometry system to continuously record calcium signals in CA1 and M1 during the temporal lobe epilepsy process.We found that calcium signals varied according to the grade of temporal lobe epilepsy episodes.In particular,cortical spreading depression,which has recently been frequently used to represent the continuously and substantially increased calcium signals,was found to correspond to complex and severe behavioral characteristics of temporal lobe epilepsy ranging from gradeⅡto gradeⅤ.However,vigorous calcium oscillations and highly synchronized calcium signals in CA1 and M1 were strongly related to convulsive motor seizures.Chemogenetic inhibition of pyramidal neurons in CA1 significantly attenuated the amplitudes of the calcium signals corresponding to gradeⅠepisodes.In addition,the latency of cortical spreading depression was prolonged,and the above-mentioned abnormal calcium signals in CA1 and M1 were also significantly reduced.Intriguingly,it was possible to rescue the altered intracellular calcium dynamics.Via simultaneous analysis of calcium signals and epileptic behaviors,we found that the progression of temporal lobe epilepsy was alleviated when specific calcium signals were reduced,and that the end-point behaviors of temporal lobe epilepsy were improved.Our results indicate that the calcium dynamic between CA1 and M1 may reflect specific epileptic behaviors corresponding to different grades.Furthermore,the selective regulation of abnormal calcium signals in CA1 pyramidal neurons appears to effectively alleviate temporal lobe epilepsy,thereby providing a potential molecular mechanism for a new temporal lobe epilepsy diagnosis and treatment strategy. 展开更多
关键词 CA^(2+) calcium signals chemogenetic methods HIPPOCAMPUS primary motor cortex pyramidal neurons temporal lobe epilepsy
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Towards carbon neutrality of calcium carbide-based acetylene production with sustainable biomass resources 被引量:2
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作者 Peng Jiang Guanhan Zhao +4 位作者 Hao Zhang Tuo Ji Liwen Mu Xiaohua Lu Jiahua Zhu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第6期1068-1078,共11页
Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but a... Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but also the raw material for CaC_(2) synthesis is from coal.Here,a comprehensive biomass-to-acetylene process was constructed that integrated several units including biomass pyrolysis,oxygen-thermal CaC_(2) fabrication and calcium looping.For comparison,a coal-to-acetylene process was also established by using coal as feedstock.The carbon efficiency,energy efficiency and environmental impacts of the bio-based calcium carbide acetylene(BCCA)and coal-based calcium carbide acetylene(CCCA)processes were systematically analyzed.Moreover,the environmental impacts were further evaluated by applying thermal integration at system level and energy substitution in CaC_(2) furnace.Even though the BCCA process showed lower carbon efficiency and energy efficiency than that of the CCCA process,life cycle assessment demonstrated the BCCA(1.873 kgCO_(2eq) kg-prod^(-1))a lower carbon footprint process which is 0.366 kgCO_(2eq) kg-prod^(-1) lower compared to the CCCA process.With sustainable energy(biomass power)substitution in CaC_(2) furnace,an even lower GWP value of 1.377 kgCO_(2eq) kg-prod^(-1) can be achieved in BCCA process.This work performed a systematic analysis on integrating biomass into industrial acetylene production,and revealed the positive role of biomass as raw material(carbon)and energy supplier. 展开更多
关键词 Biomass pyrolysis CO_(2)mitigation calcium carbide ACETYLENE calcium loop
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Elaidic acid leads to mitochondrial dysfunction via mitochondria-associated membranes triggers disruption of mitochondrial calcium fluxes 被引量:2
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作者 Hui Liu Xuenan Li +4 位作者 Ziyue Wang Lu Li Yucai Li Haiyang Yan Yuan Yuan 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期287-298,共12页
Elaidic acid(EA)stimulation can lead to endoplasmic reticulum stress(ERS),accompanied by a large release of Ca^(2+),and ultimately the activation of NLRP3 inflammasome in Kupffer cells(KCs).Mitochondrial instability o... Elaidic acid(EA)stimulation can lead to endoplasmic reticulum stress(ERS),accompanied by a large release of Ca^(2+),and ultimately the activation of NLRP3 inflammasome in Kupffer cells(KCs).Mitochondrial instability or dysfunction may be the key stimulating factors to activate NLRP3 inflammasome,and sustained Ca^(2+)transfer can result in mitochondrial dysfunction.We focused on KCs to explore the damage to mitochondria by EA.After EA stimulation,cells produced an oxidative stress(OS)response with a significant increase in ROS release.Immunoprecipitation experiments and the addition of inhibitors revealed that the increase in the level of intracellular Ca^(2+)led to Ca^(2+)accumulation in the mitochondrial matrix via mitochondria-associated membranes(MAMs).This was accompanied by a significant release of m ROS,loss of MMP and ATP,and a significant increase in mitochondrial permeability transition pore opening,ultimately leading to mitochondrial instability.These findings confirmed the mechanism that EA induced mitochondrial Ca^(2+)imbalance in KCs via MAM,ultimately leading to mitochondrial dysfunction.Meanwhile,EA induced OS and the decrease of MMP and ATP in rat liver,and significant lesions were found in liver mitochondria.Swelling of the inner mitochondrial cristae and mitochondrial vacuolization occurred,with a marked increase in lipid droplets. 展开更多
关键词 Elaidic acid(EA) Mitochondria-associated membranes(MAMs) calcium Endoplasmic reticulum Mitochondria dysfunction
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Phase separation and transcriptional regulation in cancer development 被引量:1
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作者 Yan Gu Ke Wei Jun Wang 《Journal of Biomedical Research》 CAS CSCD 2024年第4期307-321,共15页
Liquid-liquid phase separation,a novel biochemical phenomenon,has been increasingly studied for its medical applications.It underlies the formation of membrane-less organelles and is involved in many cellular and biol... Liquid-liquid phase separation,a novel biochemical phenomenon,has been increasingly studied for its medical applications.It underlies the formation of membrane-less organelles and is involved in many cellular and biological processes.During transcriptional regulation,dynamic condensates are formed through interactions between transcriptional elements,such as transcription factors,coactivators,and mediators.Cancer is a disease characterized by uncontrolled cell proliferation,but the precise mechanisms underlying tumorigenesis often remain to be elucidated.Emerging evidence has linked abnormal transcriptional condensates to several diseases,especially cancer,implying that phase separation plays an important role in tumorigenesis.Condensates formed by phase separation may have an effect on gene transcription in tumors.In the present review,we focus on the correlation between phase separation and transcriptional regulation,as well as how this phenomenon contributes to cancer development. 展开更多
关键词 phase separation transcription regulation CANCER super-enhancer CONDENSATES
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Flexible bidirectional pulse charging regulation achieving long-life lithium-ion batteries 被引量:1
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作者 Xiaodong Xu Shengjin Tang +9 位作者 Xuebing Han Languang Lu Yudi Qin Jiuyu Du Yu Wu Yalun Li Chuanqiang Yu Xiaoyan Sun Xuning Feng Minggao Ouyang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期59-71,共13页
Typical application scenarios,such as vehicle to grid(V2G)and frequency regulation,have imposed significant long-life demands on lithium-ion batteries.Herein,we propose an advanced battery life-extension method employ... Typical application scenarios,such as vehicle to grid(V2G)and frequency regulation,have imposed significant long-life demands on lithium-ion batteries.Herein,we propose an advanced battery life-extension method employing bidirectional pulse charging(BPC)strategy.Unlike traditional constant current charging methods,BPC strategy not only achieves comparable charging speeds but also facilitates V2G frequency regulation simultaneously.It significantly enhances battery cycle ampere-hour throughput and demonstrates remarkable life extension capabilities.For this interesting conclusion,adopting model identification and postmortem characterization to reveal the life regulation mechanism of BPC:it mitigates battery capacity loss attributed to loss of lithium-ion inventory(LLI)in graphite anodes by intermittently regulating the overall battery voltage and anode potential using a negative charging current.Then,from the perspective of internal side reaction,the life extension mechanism is further revealed as inhibition of solid electrolyte interphase(SEI)and lithium dendrite growth by regulating voltage with a bidirectional pulse current,and a semi-empirical life degradation model combining SEI and lithium dendrite growth is developed for BPC scenarios health management,the model parameters are identified by genetic algorithm with the life simulation exhibiting an accuracy exceeding 99%.This finding indicates that under typical rate conditions,adaptable BPC strategies can extend the service life of LFP battery by approximately 123%.Consequently,the developed advanced BPC strategy offers innovative perspectives and insights for the development of long-life battery applications in the future. 展开更多
关键词 Lithium-ion battery Long-life regulation Bidirectional pulse charging Mechanism identification
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Rapid and stable calcium-looping solar thermochemical energy storage via co-doping binary sulfate and Al–Mn–Fe oxides 被引量:1
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作者 Changjian Yuan Xianglei Liu +8 位作者 Xinrui Wang Chao Song Hangbin Zheng Cheng Tian Ke Gao Nan Sun Zhixing Jiang Yimin Xuan Yulong Ding 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1290-1305,共16页
Solar thermochemical energy storage based on calcium looping(CaL)process is a promising technology for next-generation concentrated solar power(CSP)systems.However,conventional calcium carbonate(CaCO_(3))pellets suffe... Solar thermochemical energy storage based on calcium looping(CaL)process is a promising technology for next-generation concentrated solar power(CSP)systems.However,conventional calcium carbonate(CaCO_(3))pellets suffer from slow reaction kinetics,poor stability,and low solar absorptance.Here,we successfully realized high power density and highly stable solar thermochemical energy storage/release by synergistically accelerating energy storage/release via binary sulfate and promoting cycle stability,mechanical strength,and solar absorptance via Al–Mn–Fe oxides.The energy storage density of proposed CaCO_(3)pellets is still as high as 1455 kJ kg^(-1)with only a slight decay rate of 4.91%over 100 cycles,which is higher than that of state-of-the-art pellets in the literature,in stark contrast to 69.9%of pure CaCO_(3)pellets over 35 cycles.Compared with pure CaCO_(3),the energy storage power density or decomposition rate is improved by 120%due to lower activation energy and promotion of Ca^(2+)diffusion by binary sulfate.The energy release or carbonation rate rises by 10%because of high O^(2-)transport ability of molten binary sulfate.Benefiting from fast energy storage/release rate and high solar absorptance,thermochemical energy storage efficiency is enhanced by more than 50%under direct solar irradiation.This work paves the way for application of direct solar thermochemical energy storage techniques via achieving fast energy storage/release rate,high energy density,good cyclic stability,and high solar absorptance simultaneously. 展开更多
关键词 calcium looping(CaL) Solar thermochemical Energy storage Binary sulfate Fast reaction kinetics
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Transcriptional regulation in the development and dysfunction of neocortical projection neurons 被引量:1
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作者 Ningxin Wang Rong Wan Ke Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期246-254,共9页
Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord... Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord.Appropriate development of cortical projection neurons is regulated by certain essential events such as neural fate determination,proliferation,specification,differentiation,migration,survival,axonogenesis,and synaptogenesis.These processes are precisely regulated in a tempo-spatial manner by intrinsic factors,extrinsic signals,and neural activities.The generation of correct subtypes and precise connections of projection neurons is imperative not only to support the basic cortical functions(such as sensory information integration,motor coordination,and cognition)but also to prevent the onset and progression of neurodevelopmental disorders(such as intellectual disability,autism spectrum disorders,anxiety,and depression).This review mainly focuses on the recent progress of transcriptional regulations on the development and diversity of neocortical projection neurons and the clinical relevance of the failure of transcriptional modulations. 展开更多
关键词 autism spectrum disorders COGNITION DIFFERENTIATION excitatory circuits intellectual disability NEOCORTEX neurodevelopmental disorders projection neuron specification transcriptional regulation
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Effect of Fluoride on the Ion-association of Calcium Phosphate and Crystallization of Hydroxyapatite
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作者 宋昊月 CAI Meng +1 位作者 袁萍 邹朝勇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期831-838,共8页
Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and t... Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and the formation of ACP nanospheres in a buffer solution with constant ionic strength.However,the stability of ACP increased with increasing fluoride concentration,which was ascribed to the inhibitory effect of fluoride on the aggregation of ACP nanospheres and the nucleation of nanocrystals on the surface of ACP nanospheres.Furthermore,fluoride could inhibit the lateral growth of HAP nanosheets and promote the formation of rod-like crystals.These results further improve our understanding of the crystallization pathway of HAP crystals and the regulatory effects of fluoride. 展开更多
关键词 CRYSTALLIZATION amorphous calcium phosphate HYDROXYAPATITE FLUORIDE
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Compartmentalized regulation of organelle integrity in neurodegenerative diseases:lessons from the Drosophila motor neuron
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作者 Hyun Sung 《Neural Regeneration Research》 SCIE CAS 2025年第1期195-196,共2页
Neurons are highly polarized,morphologically asymmetric,and functionally compartmentalized cells that contain long axons extending from the cell body.For this reason,their maintenance relies on spatiotemporal regulati... Neurons are highly polarized,morphologically asymmetric,and functionally compartmentalized cells that contain long axons extending from the cell body.For this reason,their maintenance relies on spatiotemporal regulation of organelle distribution between the somatodendritic and axonal domains.Although some organelles,such as mitochondria and smooth endoplasmic reticulum,are widely distributed throughout the neuron,others are segregated to either the somatodendritic or axonal compartment.For example,Golgi outposts and acidified lysosomes are predominantly present in the somatodendritic domain and rarely distributed along the axon,whereas newly formed autophagosomes and synaptic vesicles are mainly distributed in the distal axon(Britt et al.,2016). 展开更多
关键词 ORGANELLE regulation DISTRIBUTION
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Purification of Produced Water from a Sour Oilfield in South Kuwait. 2. Oil-Water Separation and Crystallization of Calcium Carbonate
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作者 Feras Al Salem Najood Almansoori +4 位作者 Hanifa AlBalooshi Nouf Alshehhi Maitha Almheiri Vijo Poulose Thies Thiemann 《Journal of Water Resource and Protection》 CAS 2024年第7期467-488,共22页
Oil-water separation for produced water (PW) originating from an oil extraction site in South Kuwait was carried out using bleached, esterified cellulosic material from used coffee grounds. Thereafter, earth-alkaline ... Oil-water separation for produced water (PW) originating from an oil extraction site in South Kuwait was carried out using bleached, esterified cellulosic material from used coffee grounds. Thereafter, earth-alkaline metal ions, specifically calcium ions, of the de-oiled PW were removed by precipitation with sodium carbonate to give access to pure sodium chloride as industrial salt from the remaining PW. While the purity of the precipitated calcium carbonate (CaCO3) depends on the precipitation conditions, CaCO3 of up to 95.48% purity can be obtained, which makes it a salable product. The precipitation of CaCO3 decreases the amount of calcium ions in PW from 11,300 ppm to 84 ppm. 展开更多
关键词 Produced Water Oil and Gas Bleached Biomass Adsorption Filtration Crystallization of calcium Chloride
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Preparation of high-purity fluorite and nanoscale calcium carbonate from low-grade fluorite
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作者 Qianqian Lu Haisheng Han +5 位作者 Wenjuan Sun Xingfei Zhang Weiwei Wang Bilan Zhang Wensheng Chen Qin Zou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1198-1207,共10页
Flotation separation of calcite from fluorite is a challenge on low-grade fluorite flotation that limits the recovery and purity of fluorite concentrate.A new acid leaching–flotation process for fluorite is proposed ... Flotation separation of calcite from fluorite is a challenge on low-grade fluorite flotation that limits the recovery and purity of fluorite concentrate.A new acid leaching–flotation process for fluorite is proposed in this work.This innovative process raised the fluor-ite’s grade to 97.26wt%while producing nanoscale calcium carbonate from its leachate,which contained plenty of calcium ions.On the production of nanoscale calcium carbonate,the impacts of concentration,temperature,and titration rate were examined.By modifying the process conditions and utilizing crystal conditioning agents,calcite-type and amorphous calcium carbonates with corresponding particle sizes of 1.823 and 1.511μm were produced.The influence of the impurity ions Mn^(2+),Mg^(2+),and Fe^(3+)was demonstrated to reduce the particle size of nanoscale calcium carbonate and make crystal shape easier to manage in the fluorite leach solution system compared with the calcium chloride solution.The combination of the acid leaching–flotation process and the nanoscale calcium carbonate preparation method improved the grade of fluorite while recovering calcite resources,thus presenting a novel idea for the effective and clean usage of low-quality fluorite resources with embedded microfine particles. 展开更多
关键词 FLUORITE CALCITE nanoscale calcium carbonate waste recovery
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NECAB family of neuronal calcium-binding proteins in health and disease
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作者 Diones Bueno Michael K.E.Schafer +2 位作者 Sudena Wang Michael J.Schmeisser Axel Methner 《Neural Regeneration Research》 SCIE CAS 2025年第5期1236-1243,共8页
The N-terminal EF-hand calcium-binding proteins 1–3(NECAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one EF-hand calcium-binding domain and a functionally le... The N-terminal EF-hand calcium-binding proteins 1–3(NECAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one EF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NECAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NECAB2 interacts with predominantly striatal G-protein-coupled receptors, while NECAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NECAB proteins exhibit distinct subcellular localizations: NECAB1 is found in the nucleus and cytosol, NECAB2 resides in endosomes and the plasma membrane, and NECAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NECAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NECAB proteins by controlling the availability of protein–protein interaction domains situated between the EF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interaction partners, and the physiological and pathophysiological role of the NECAB family. 展开更多
关键词 calcium EF hand MITOCHONDRIA nervous system signal transduction
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High-pressure study on calcium azide(Ca(N_(3))_(2)):Bending of azide ions stabilizes the structure
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作者 武晓鑫 王颖健 +7 位作者 李思琪 吕俊呈 王婧姝 杨丽华 张旗 刘艳清 张俊凯 贾洪声 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期542-548,共7页
The high-pressure structure and elastic properties of calcium azide(Ca(N_(3))_(2))were investigated using in-situ highpressure x-ray diffraction and Raman scattering up to 54 GPa and 19 GPa,respectively.The compressib... The high-pressure structure and elastic properties of calcium azide(Ca(N_(3))_(2))were investigated using in-situ highpressure x-ray diffraction and Raman scattering up to 54 GPa and 19 GPa,respectively.The compressibility of Ca(N_(3))_(2)changed as the pressure increased,and no phase transition occurred within the pressure from ambient pressure up to 54 GPa.The measured zero-pressure bulk modulus of Ca(N_(3))_(2)is higher than that of other alkali metal azides,due to differences in the ionic character of their metal-azide bonds.Using CASTEP,all vibration modes of Ca(N_(3))_(2)were accurately identified in the vibrational spectrum at ambient pressure.In the high-pressure vibration study,several external modes(ext.)and internal bending modes(ν_(2))of azide anions(N_(3)^(-))softened up to~7 GPa and then hardened beyond that pressure.This evidence is consistent with the variation observed in the F_(E)–f_(E)data analyzed from the XRD result,where the slope of the curve changes at 7.1 GPa.The main behaviors under pressure are the alternating compression,rotation,and bending of N_(3)^(-)ions.The bending behavior makes the structure of Ca(N_(3))_(2)more stable under pressure. 展开更多
关键词 high pressure calcium azide azide anions
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Hydration Behavior and Cementitious Properties of Calcium Carbonate-aluminate Minerals Composite
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作者 王冲 周帅 +2 位作者 ZOU Luyao LIU Jiawen ZHENG Yalin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期126-133,共8页
The purpose of this research is to investigate the hydration behavior and cementitious properties of the mixture of calcium carbonate and aluminate, and to explore whether it can be adopted as a new low-carbon cementi... The purpose of this research is to investigate the hydration behavior and cementitious properties of the mixture of calcium carbonate and aluminate, and to explore whether it can be adopted as a new low-carbon cementitious material. The composite system of calcium carbonate and aluminate minerals is studied by measuring the component of hydration products, the hydration heat, setting time and compressive strength.The results prove that the composite system has certain cementitious properties and is feasible to prepare new low-carbon cement. 展开更多
关键词 LIMESTONE hydrated calcium carboaluminate cementitious properties mechanical properties
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The glutamate receptor gene GLR3.3:A bridge of calciummediated root development in poplar
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作者 Yi An Ya Geng +5 位作者 Yu Liu Xiao Han Lichao Huang Wei Zeng Jin Zhang Mengzhu Lu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第6期1449-1462,共14页
Poplar is one of the fastest-growing temperate trees in the world and is widely used in ornamental horticulture for shade.The root is essential for tree growth and development and its utilization potential is huge.Cal... Poplar is one of the fastest-growing temperate trees in the world and is widely used in ornamental horticulture for shade.The root is essential for tree growth and development and its utilization potential is huge.Calcium(Ca),as a signaling molecule,is involved in the regulation of plant root development.However,the detailed underlying regulatory mechanism is elusive.In this study,we analyzed the morphological and transcriptomic variations of 84K poplar(Populus alba×P.glandulosa)in response to different calcium concentrations and found that low Ca^(2+)(1 mmol·L^(-1))promoted lateral root development,while deficiency(0.1 mmol·L^(-1)Ca^(2+))inhibited lateral root development.Co-expression analysis showed that Ca^(2+)channel glutamate receptors(GLRs)were present in various modules with significance for root development.Two GLR paralogous genes,PagGLR3.3a and Pag GLR3.3b,were mainly expressed in roots and up-regulated under Ca^(2+)deficiency.The CRISPR/Cas9-mediated signal gene(crispr-PagGLR3.3a,PagGLR3.3b)and double gene(crispr-PagGLR3.3ab)mutants presented more and longer lateral roots.Anatomical analysis showed that crispr-PagGLR3.3ab plants had more xylem cells and promoted the development of secondary vascular tissues.Further transcriptomic analysis suggested that knockout of PagGLR3.3a and PagGLR3.3b led to the up-regulation of several genes related to protein phosphorylation,auxin efflux,lignin and hemicellulose biosynthesis as well as transcriptional regulation,which might contribute to lateral root growth.This study not only provides novel insight into how the Ca^(2+)channels mediated root growth and development in trees,but also provides a directive breeding of new poplar species for biofuel and bioenergy production. 展开更多
关键词 Glutamate receptor calcium Root development Lateral root POPLAR
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Double-Blind, Parallel Group Study to Compare the Clinical Effectiveness of Calcium Dobesilate 500 mg BID vs. Calcium Dobesilate LP 1 g OD, in Patients with Chronic Venous Insufficiency of the Lower Limbs
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作者 Ramón Téllez Méndez Maria González Yibirin David Rincón Matute 《International Journal of Clinical Medicine》 CAS 2024年第5期211-223,共13页
Background: Chronic venous insufficiency (CVI) describes a condition that affects the venous system of the lower extremities due to venous hypertension (VH. The prevalence is between 5% - 30%. CVI is associated with o... Background: Chronic venous insufficiency (CVI) describes a condition that affects the venous system of the lower extremities due to venous hypertension (VH. The prevalence is between 5% - 30%. CVI is associated with older age, smoking, lower extremity trauma, presence of an arteriovenous shunt, and elevated estrogen levels. All patients should be initially treated with conservative management. Venoactive drugs like calcium dobesilate are useful. Objectives: The primary objective compared the clinical improvement in patients with CVI, grades 0 - 3 of the CEAP classification of chronic venous disease, produced by two formulations of calcium dobesilate: calcium dobesilate LP 1 g OD vs calcium dobesilate 500 mg BID, immediate release. The secondary objective assessed the side effects of both formulations. Method: All patients took one tablet and one capsule at 7 am, and one capsule at 7 pm, for 8 weeks. One group received dobesilate 1 g OD and the other group received dobesilate 500 md BID. They were evaluated after 15, 30 and 60 days of treatment, using the symptom evaluation scale. Results: In both groups, there was a significant decrease in the symptom score after 15 days. Four patients in the Dobesilate OD group: had adverse effects, which did not require suspension of treatment. In the BID dobesilate group, there was one therapeutic failure, and one case of gastric discomfort. Conclusions: Prolonged-release Calcium dobesilate 1 g OD is as effective as calcium dobesilate 500 mg BID for the treatment of patients with chronic venous insufficiency. 展开更多
关键词 Chronic Venous Insufficiency (CVI) calcium Dobesilate CEAP Classification Adverse Effects Treatment Adherence
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Biomineralization of soil with crude soybean urease using different calcium salts
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作者 Yajie Weng Junjie Zheng +2 位作者 Hanjiang Lai Mingjuan Cui Xingzhi Ding 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1788-1798,共11页
Calcium salt is an important contributing factor for calcium-based biomineralization.To study the effect of calcium salt on soil biomineralization using crude soybean urease,the calcium salts,including the calcium chl... Calcium salt is an important contributing factor for calcium-based biomineralization.To study the effect of calcium salt on soil biomineralization using crude soybean urease,the calcium salts,including the calcium chloride (CaCl_(2)),calcium acetate ((CH_(3)COO)_(2)Ca) and calcium nitrate (Ca(NO_(3))_(2)),were used to prepare the biotreatment solution to carry out the biomineralization tests in this paper.Two series of biomineralization tests in solution and sand column,respectively,were conducted.Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were performed to determine the microscopic characteristics of the precipitated calcium carbonate (CaCO_(3)) crystals.The experimental results indicate that the biomineralization effect is the best for the CaCl2 case,followed by (CH_(3)COO)_(2)Ca,and worst for Ca(NO_(3))_(2) under the test conditions of this study (i.e.1 mol/L of calcium salt-urea).The mechanism for the effect of the calcium salt on the biomineralization of crude soybean urease mainly involves: (1) inhibition of urease activity,and (2) influence on the crystal size and morphology of CaCO_(3).Besides Ca^(2+) ,the anions in solution can inhibit the activity of crude soybean urease,and NO_(3)− has a stronger inhibitory effect on the urease activity compared with both CH_(3)COO^(−) and Cl^(−) .The co-inhibition of Ca^(2+) and NO_(3)− on the activity of urease is the key reason for the worst biomineralization of the Ca(NO_(3))_(2) case in this study.The difference in biomineralization between the CaCl_(2) and (CH_(3)COO)_(2) Ca cases is strongly correlated with the crystal morphology of the precipitated CaCO_(3). 展开更多
关键词 BIOMINERALIZATION Crude soybean urease calcium salt Influence mechanism
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Contract Mechanism of Water Environment Regulation for Small and Medium Sized Enterprises Based on Optimal Control Theory
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作者 Shuang Zhao Hongbin Gu +2 位作者 Lianfang Xue Dongsheng Wang Bin Huang 《Journal of Water Resource and Protection》 CAS 2024年第7期538-556,共20页
The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of trea... The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of treatment. How enterprises can make reasonable decisions on their water environment behavior based on the external environment and their own factors is of great significance for scientifically and effectively designing water environment regulation mechanisms. Based on optimal control theory, this study investigates the design of contractual mechanisms for water environmental regulation for small and medium-sized enterprises. The enterprise is regarded as an independent economic entity that can adopt optimal control strategies to maximize its own interests. Based on the participation of multiple subjects including the government, enterprises, and the public, an optimal control strategy model for enterprises under contractual water environmental regulation is constructed using optimal control theory, and a method for calculating the amount of unit pollutant penalties is derived. The water pollutant treatment cost data of a paper company is selected to conduct empirical numerical analysis on the model. The results show that the increase in the probability of government regulation and public participation, as well as the decrease in local government protection for enterprises, can achieve the same regulatory effect while reducing the number of administrative penalties per unit. Finally, the implementation process of contractual water environmental regulation for small and medium-sized enterprises is designed. 展开更多
关键词 Optimal Control Theory Small and Medium-Sized Enterprises Water Environment regulation Contract Mechanism
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Astrocytic calcium waves:unveiling their roles in sleep and arousal modulation
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作者 Erxi Wu Dan Qi +1 位作者 Damir Nizamutdinov Jason H.Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期984-987,共4页
Neuron-astrocyte interactions are vital for the brain’s connectome.Understanding astrocyte activities is crucial for comprehending the complex neural network,particularly the population-level functions of neurons in ... Neuron-astrocyte interactions are vital for the brain’s connectome.Understanding astrocyte activities is crucial for comprehending the complex neural network,particularly the population-level functions of neurons in different cortical states and associated behaviors in mammals.Studies on animal sleep and wakefulness have revealed distinct cortical synchrony patterns between neurons.Astrocytes,outnumbering neurons by nearly fivefold,support and regulate neuronal and synaptic function.Recent research on astrocyte activation during cortical state transitions has emphasized the influence of norepinephrine as a neurotransmitter and calcium waves as key components of ion channel signaling.This summary focuses on a few recent studies investigating astrocyte-neuron interactions in mouse models during sleep,wakefulness,and arousal levels,exploring the involvement of noradrenaline signaling,ion channels,and glutamatergic signaling in different cortical states.These findings highlight the significant impact of astrocytes on large-scale neuronal networks,influencing brain activity and responsiveness.Targeting astrocytic signaling pathways shows promise for treating sleep disorders and arousal dysregulation.More research is needed to understand astrocytic calcium signaling in different brain regions and its implications for dysregulated brain states,requiring future human studies to comprehensively investigate neuron-astrocyte interactions and pave the way for therapeutic interventions in sleep-and arousal-related disorders. 展开更多
关键词 AROUSAL ASTROCYTE calcium waves locus coeruleus neuron-astrocyte interaction NOREPINEPHRINE SLEEP WAKEFULNESS
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