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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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Bio-cementation for tidal erosion resistance improvement of foreshore slopes based on microbially induced magnesium and calcium precipitation
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作者 Xiaohao Sun Junjie Wang +3 位作者 Hengxing Wang Linchang Miao Ziming Cao Linyu Wu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1696-1708,共13页
In most coastal and estuarine areas,tides easily cause surface erosion and even slope failure,resulting in severe land losses,deterioration of coastal infrastructure,and increased floods.The bio-cementation technique ... In most coastal and estuarine areas,tides easily cause surface erosion and even slope failure,resulting in severe land losses,deterioration of coastal infrastructure,and increased floods.The bio-cementation technique has been previously demonstrated to effectively improve the erosion resistance of slopes.Seawater contains magnesium ions(Mg2+)with a higher concentration than calcium ions(Ca2+);therefore,Mg2+and Ca2+were used together for bio-cementation in this study at various Mg2+/Ca2+ratios as the microbially induced magnesium and calcium precipitation(MIMCP)treatment.Slope angles,surface strengths,precipitation contents,major phases,and microscopic characteristics of precipitation were used to evaluate the treatment effects.Results showed that the MIMCP treatment markedly enhanced the erosion resistance of slopes.Decreased Mg2+/Ca2+ratios resulted in a smaller change in angles and fewer soil losses,especially the Mg2+concentration below 0.2 M.The decreased Mg2+/Ca2+ratio achieved increased precipitation contents,which contributed to better erosion resistance and higher surface strengths.Additionally,the production of aragonite would benefit from elevated Mg2+concentrations and a higher Ca2+concentration led to more nesquehonite in magnesium precipitation crystals.The slopes with an initial angle of 53°had worse erosion resistance than the slopes with an initial angle of 35°,but the Mg2+/Ca2+ratios of 0.2:0.8,0.1:0.9,and 0:1.0 were effective for both slope stabilization and erosion mitigation to a great extent.The results are of great significance for the application of MIMCP to improve erosion resistance of foreshore slopes and the MIMCP technique has promising application potential in marine engineering. 展开更多
关键词 Bio-cementation Erosion resistance Foreshore slope stabilization Magnesium ions calcium ions
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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 (CaCl2 ),calcium acetate ((CH3 COO)2 Ca) and calcium nitrate (Ca(NO3 )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 (CaCO3 ) crystals.The experimental results indicate that the biomineralization effect is the best for the CaCl2 case,followed by (CH3 COO)2 Ca,and worst for Ca(NO3 )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 CaCO3 .Besides Ca2+ ,the anions in solution can inhibit the activity of crude soybean urease,and NO3 − has a stronger inhibitory effect on the urease activity compared with both CH3 COO− and Cl− .The co-inhibition of Ca2+ and NO3 − on the activity of urease is the key reason for the worst biomineralization of the Ca(NO3 )2 case in this study.The difference in biomineralization between the CaCl2 and (CH3 COO)2 Ca cases is strongly correlated with the crystal morphology of the precipitated CaCO3 . 展开更多
关键词 BIOMINERALIZATION Crude soybean urease calcium salt Influence mechanism
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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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Suppressing a mitochondrial calcium uniporter activates the calcium signaling pathway and promotes cell elongation in cotton
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作者 Yujia Duan Xiaoguang Shang +4 位作者 Ruiping Tian Weixi Li Xiaohui Song Dayong Zhang Wangzhen Guo 《The Crop Journal》 SCIE CSCD 2024年第2期411-421,共11页
Mitochondrial calcium uniporter(MCU)is a conserved calcium ion(Ca^(2+))transporter in the mitochondrial inner membrane of eukaryotic cells.How MCU proteins regulate Ca^(2+)flow and modulate plant cell development rema... Mitochondrial calcium uniporter(MCU)is a conserved calcium ion(Ca^(2+))transporter in the mitochondrial inner membrane of eukaryotic cells.How MCU proteins regulate Ca^(2+)flow and modulate plant cell development remain largely unclear.Here,we identified the gene GhMCU4 encoding a MCU protein that negatively regulates plant development and fiber elongation in cotton(Gossypium hirsutum).GhMCU4expressed constitutively in various tissues with the higher transcripts in elongating fiber cells.Knockdown of GhMCU4 in cotton significantly elevated the plant height and root length.The calcium signaling pathway was significantly activated and calcium sensor genes,including Ca^(2+)dependent modulator of interactor of constitutively active ROP(GhCMI1),calmodulin like protein(GhCML46),calciumdependent protein kinases(GhCPKs),calcineurin B-like protein(GhCBLs),and CBL-interacting protein kinases(GhCIPKs),were dramatically upregulated in GhMCU4-silenced plants.Metabolic processes were preferentially enriched,and genes related to regulation of transcription were upregulated in GhMCU4-silenced plants.The contents of Ca^(2+)and H_(2)O_(2)were significantly increased in roots and leaves of GhMCU4-silenced plants.Fiber length and Ca^(2+)and H_(2)O_(2)contents in fibers were significantly increased in GhMCU4-silenced plants.This study indicated that GhMCU4 plays a negative role in regulating cell elongation in cotton,thus expanding understanding in the role of MCU proteins in plant growth and development. 展开更多
关键词 calcium signaling Hydrogen peroxide Metabolic processed Gossypium hirsutum
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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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Calcium-fortified fresh milk ameliorates postmenopausal osteoporosis via regulation of bone metabolism and gut microbiota in ovariectomized rats
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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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Elaidic acid leads to mitochondrial dysfunction via mitochondria-associated membranes triggers disruption of mitochondrial calcium fluxes
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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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Blood Calcium as a Protective Factor against Traumatic Fracture
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作者 Xin Zhang Quanquan Zhang +7 位作者 Yinjun Luo Tao Feng Yue Hu Ying Li Wenjing Yu Linghan Guo Jinhua Wang Suchan Liao 《Journal of Biosciences and Medicines》 2024年第3期328-336,共9页
Purpose: This study aims to investigate the predictive value of blood calcium in the prognosis of traumatic fracture. Methods: A retrospective experimental design was employed, 112 cases (52 non-fracture and 60 trauma... Purpose: This study aims to investigate the predictive value of blood calcium in the prognosis of traumatic fracture. Methods: A retrospective experimental design was employed, 112 cases (52 non-fracture and 60 traumatic fracture) were randomly selected. The type of fracture complies with WHO-recommended (2019) diagnostic criteria for osteoporosis combined with fracture. The blood pressure (BP) was measured by OMRON’s HEM-7136 model electronic blood pressure monitor. Blood calcium (Ca<sup>2+</sup>), and blood phosphorus (P) values were measured using Colorimetric Roche kits on a Roche/Hitachi fully automated biochemical analyzer. Data collection and analysis followed. Results: Higher levels of age, systolic and diastolic blood pressures were found in the traumatic fracture group compared to the control group, whereas weight, height, and blood phosphorus did not differ significantly (P adjusting for age, systolic blood pressure, diastolic blood pressure, and blood phosphorus, binary logistic regression analysis revealed that blood calcium was a protective factor against traumatic fracture (β = -26.85, OR = 0.00, 95% CI = 0.00 -0.02, P = 0.022). Conclusion: The findings suggest that high and low blood calcium levels may serve as useful indicators in predicting the prognosis of fractures resulting from trauma. 展开更多
关键词 Traumatic Fracture FRACTURE Biochemical Indicators Blood calcium Prognostic Value
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Dry Mix Slag—High-Calcium Fly Ash Binder. Part Two: Durability
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作者 Alexey Brykov Mikhail Voronkov 《Materials Sciences and Applications》 2024年第3期37-51,共15页
This work investigates durability of cement-free mortars with a binder comprised of ground granulated blast furnace slag (GGBFS) activated by high-calcium fly ash (HCFA) and sodium carbonate (Na<sub>2</sub>... This work investigates durability of cement-free mortars with a binder comprised of ground granulated blast furnace slag (GGBFS) activated by high-calcium fly ash (HCFA) and sodium carbonate (Na<sub>2</sub>CO<sub>3</sub>): the soundness, sulfate resistance, alkali-silica reactivity and efflorescence factors are considered. Results of tests show that such mortars are resistant to alkali-silica expansion. Mortars are also sulfate-resistant when the amount of HCFA in the complex binder is within a limit of 10 wt%. The fineness of fly ash determines its’ ability to activate GGBFS hydration, and influence soundness of the binder, early strength development, sulfate resistance and efflorescence behavior. The present article is a continuation of authors’ work, previously published in MSA, Vol. 14, 240-254. 展开更多
关键词 Ground Granulated Blast-Furnace Slag High-calcium Fly-Ash Sodium Car-bonate Blast-Furnace Slag Binder DURABILITY ASR Sulfate Attack SOUNDNESS EFFLORESCENCE
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Geotechnical investigation of low-plasticity organic soil treated with nano-calcium carbonate
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作者 Govindarajan Kannan Brendan C.O’Kelly Evangelin Ramani Sujatha 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期500-509,共10页
Soil stabilization using nanomaterials is an emerging research area although,to date,its investigation has mostly been laboratory-based and therefore requires extensive study for transfer to practical field ap-plicati... Soil stabilization using nanomaterials is an emerging research area although,to date,its investigation has mostly been laboratory-based and therefore requires extensive study for transfer to practical field ap-plications.The present study advocates nano-calcium carbonate(NCC)material,a relatively unexplored nanomaterial additive,for stabilization of low-plasticity fine-grained soil having moderate organic content.The plasticity index,compaction,unconfined compressive strength(UCS),compressibility and permeability characteristics of the 0.2%,0.4%,0.6%and 0.8%NCC-treated soil,and untreated soil(as control),were determined,including investigations of the effect of up to 90-d curing on the UCS and permeability properties.In terms of UCS improvement,0.4%NCC addition was identified as the optimum dosage,mobilizing a UCS at 90-d curing of almost twice that for the untreated soil.For treated soil,particle aggregation arising from NCC addition initially produced an increase in the permeability coef-ficient,but its magnitude decreased for increased curing owing to calcium silicate hydrate(CSH)gel formation,although still remaining higher compared to the untreated soil for all dosages and curing periods investigated.Compression index decreased for all NCC-treated soil investigated.SEM micro-graphs indicated the presence of gel patches along with particle aggregation.X-ray diffraction(XRD)results showed the presence of hydration products,such as CSH.Significant increases in UCS are initially attributed to void filling and then because of CSH gel formation with increased curing. 展开更多
关键词 Organic silt calcium carbonate Nano-calcium carbonate(NCC) calcium silicate hydrate(CSH) Soil stabilization
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Phosphate,calcium,and vitamin D signaling,transport,and metabolism in the endometria of cyclic ewes 被引量:1
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作者 Claire Stenhouse Makenzie G.Newton +4 位作者 Katherine M.Halloran Robyn M.Moses Nirvay Sah Larry J.Suva Fuller W.Bazer 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1012-1025,共14页
Background Recent evidence suggests important roles for progesterone(P4)and interferon tau in the regulation of calcium,phosphate,and vitamin D signaling in the uteri of pregnant sheep.However,the effects of P4 and es... Background Recent evidence suggests important roles for progesterone(P4)and interferon tau in the regulation of calcium,phosphate,and vitamin D signaling in the uteri of pregnant sheep.However,the effects of P4 and estradiol(E2),with respect to the expression of their receptors PGR and ESR1,respectively,in uterine epithelia on mineral signaling during the estrous cycle has not been investigated.Estrous cycles of mature Suffolk ewes were synchronized,prostaglandin F2αwas administered,and ewes were observed for estrus(designated as Day 0)in the presence of vasectomized rams.On Days 1,9,or 14 of the estrous cycle,hysterectomies were performed.Results 25-hydroxyvitamin D was more abundant in plasma from ewes on Day 14 than Day 1(P<0.05).Expression of fibroblast growth factor receptor 2(FGFR2),a disintegrin and metalloprotease 17(ADAM17),and parathyroid hormone-related protein(PTHrP)mRNAs was greater in endometria on Day 9 compared to Days 1 and 14(P<0.01).Similarly,expression of transient receptor potential cation channel subfamily V member 6(TRPV6)mRNA was greater in endometria on Day 9 than Day 1(P<0.05).ATPase plasma membrane Ca^(2+)transporting 4(ATP2B4)and S100 calcium binding protein G(S100G)mRNA expression was greater in endometria on Day 14 than on Days 1 and 9(P<0.01).In contrast,endometrial expression of vitamin D receptor(VDR)mRNA was lower on Days 9 and 14 than Day 1(P<0.01).Expression of klotho(KL)(P<0.05)and cytochrome P450 family 24 subfamily A member 1(CYP24)(P<0.01)mRNAs was lower on Day 14 than Days 1 and 9.ADAM17,FGF23,CYP2R1,CYP27B1,KL,and VDR proteins immunolocalized to the uterine myometrium,blood vessels,and uterine luminal(LE),superficial glandular(sGE),and glandular(GE)epithelia.S100A9 protein was weakly expressed in the uterine myometrium,LE,sGE,and GE.Immunoreactivity of CYP2R1 and KL proteins in uterine LE and sGE was less on Day 1 than on Days 9 and 14.In contrast,S100G protein was expressed exclusively by GE,and immunoreactive S100G protein was less on Day 9.S100A12 protein localized to stromal cells of the uterine stratum spongiosum and blood vessels,but not by uterine epithelial cells.Conclusion Collectively,these results implicate E2,P4,and PGR in the regulation of phosphate,calcium,and vitamin D signaling in cyclic ewes. 展开更多
关键词 calcium ENDOMETRIUM OVINE PHOSPHATE Vitamin D
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Investigation of serum calcium and vitamin D levels in superior semicircular canal dehiscence syndrome: A case control study 被引量:1
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作者 Theofano Tikka Mohd Afiq Mohd Slim +3 位作者 Trung Ton Anna Sheldon Louise J.Clark Georgios Kontorinis 《Journal of Otology》 CSCD 2023年第1期49-54,共6页
Objective: It remains unknown whether calcium metabolism has any effect on the clinical presentation of superior semicircular canal dehiscence(SSCD). Our aim was to analyse the adjusted calcium and vitamin D levels in... Objective: It remains unknown whether calcium metabolism has any effect on the clinical presentation of superior semicircular canal dehiscence(SSCD). Our aim was to analyse the adjusted calcium and vitamin D levels in SSCD patients compared to a control group.Methods: This was a prospective case-control study performed in a tertiary referral center, university teaching hospital in the UK. It included all new patients with SSCD seen in a dedicated skull base clinic over a 5-year period(2015-2019) compared to a gender and age matched control group. The main outcome of the study was adjusted calcium and Vitamin D levels between the two groups.Results: A total of 31 SSCD patients were recruited with a matched number of control patients. The mean Vitamin D level on the SSCD group was 44.8 nmoL/l(SD: 20.8) compared to 47.5 nmoL/l(SD: 27.4) on the control group(p = 0.702). Mean Adjusted calcium level was 2.34 mmoL/l(SD: 0.7) for SSCD compared to2.41 mmoL/l(SD: 0.11) for controls(p = 0.01), being within normal limits for both the SSCD and the control group.Conclusion: Our study did not identify a link between Vitamin D levels and presence of SSCD. Normal adjusted calcium values were found in both groups. Despite that a statistically significant lower calcium level was found in the SSCD group which could indicate that suboptimal levels of calcium may affect the micro-environment of the otic capsule at the SSC region. 展开更多
关键词 Superior semicircular canal DEHISCENCE calcium Vitamin D METABOLISM
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A cyclic effect of cAMP and calcium signaling contributes to jujube growth and development
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作者 WANG Li-xin WANG Lin-xia +12 位作者 ZHANG Meng-ling QU Ying-yue YUAN Ye Ehsan SADEGHNEZHAD GAO Meng-jiao ZHAO Ruo-yu QI Chao-feng GUO Xiao-xue ZHU Wen-hui LI Rui-mei DAI Li LIU Meng-jun LIU Zhi-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第7期2094-2110,共17页
3´,5´-Cyclic adenosine monophosphate(cAMP)is an important metabolite that is specifically enriched in jujube.However,the effect of cAMP on jujube cellular responses has not been comprehensively studied.Here,... 3´,5´-Cyclic adenosine monophosphate(cAMP)is an important metabolite that is specifically enriched in jujube.However,the effect of cAMP on jujube cellular responses has not been comprehensively studied.Here,we established jujube cell suspension cultures and investigated the calcium influx in response to cAMP treatment through protoplast isolation and fluorescence intensity.Firstly,cAMP treatment could promote jujube growth and increase the content of endogenous cAMP.Using transcriptome analysis with transgenic Arabidopsis plants overexpressing adenylate cyclase(ZjAC)as a positive control,we identified 60 calcium-related differential expressed genes(DEGs)that contributed to the calcium signaling and inter-or intra-cellular responses.Pharmacological treatments such as cAMP and the calcium ionophore A23187 could induce ZjAC expression,the accumulation of cAMP and calcium influx in jujube cells,while ethylene glycol tetraacetic acid(EGTA)or bithionol treatment inhibited these changes.Moreover,the calcium channels and transporters in calcium influx,such as the ZjCNGC2 channel and the mitogen activated protein(MAP)kinase pathway,could be activated by cAMP treatment.In summary,our findings demonstrated that cAMP biosynthesis is dependent on calcium influx and the amplifying effect between calcium and cAMP may be involved in intracellular signal induction,which might contribute to the growth and development of jujube. 展开更多
关键词 CAMP calcium growth suspension cells PROTOPLAST signaling JUJUBE
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Elevated extracellular calcium ions accelerate the proliferation and migration of HepG2 cells and decrease cisplatin sensitivity
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作者 Haozhe Xu Yiming Zhou +6 位作者 Jing Guo Tao Ling Yujie Xu Ting Zhao Chuanxin Shi Zhongping Su Qiang You 《The Journal of Biomedical Research》 CAS CSCD 2023年第5期340-354,共15页
Hepatoblastoma is the most frequent liver malignancy in children.HepG2 has been discovered as a hepatoblastoma-derived cell line and tends to form clumps in culture.Intriguingly,we observed that the addition of calciu... Hepatoblastoma is the most frequent liver malignancy in children.HepG2 has been discovered as a hepatoblastoma-derived cell line and tends to form clumps in culture.Intriguingly,we observed that the addition of calcium ions reduced cell clumping and disassociated HepG2 cells.The calcium signal is in connection with a series of processes critical in the tumorigenesis.Here,we demonstrated that extracellular calcium ions induced morphological changes and enhanced the epithelial-mesenchymal transition in HepG2 cells.Mechanistically,calcium ions promoted HepG2 proliferation and migration by up-regulating the phosphorylation levels of focal adhesion kinase(FAK),protein kinase B,and p38 mitogen-activated protein kinase.The inhibitor of FAK or Ca2+/calmodulin-dependent kinaseⅡ(CaMKⅡ)reversed the Ca2+-induced effects on HepG2 cells,including cell proliferation and migration,epithelial-mesenchymal transition protein expression levels,and phosphorylation levels of FAK and protein kinase B.Moreover,calcium ions decreased HepG2 cells'sensitivity to cisplatin.Furthermore,we found that the expression levels of FAK and CaMKⅡwere increased in hepatoblastoma.The group with high expression levels of FAK and CaMKⅡexhibited significantly lower ImmunoScore as well as CD8+T and NK cells.The expression of CaMKⅡwas positively correlated with that of PDCD1 and LAG3.Correspondingly,the expression of FAK was negatively correlated with that of TNFSF9,TNFRSF4,and TNFRSF18.Collectively,extracellular calcium accelerates HepG2 cell proliferation and migration via FAK and CaMKⅡand enhances cisplatin resistance.FAK and CaMKⅡshape immune cell infiltration and responses in tumor microenvironments,thereby serving as potential targets for hepatoblastoma. 展开更多
关键词 HepG2 HEPATOBLASTOMA calcium ion FAK CaMKⅡ cisplatin resistance
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Proposal for pathogenesis-based treatment options to reduce calcium oxalate stone recurrence
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作者 Saeed R.Khan Benjamin K.Canales 《Asian Journal of Urology》 CSCD 2023年第3期246-257,共12页
Objective:Prevalence of kidney stone disease continues to increase globally with recurrence rates between 30%and 50%despite technological and scientific advances.Reduction in recurrence would improve patient outcomes ... Objective:Prevalence of kidney stone disease continues to increase globally with recurrence rates between 30%and 50%despite technological and scientific advances.Reduction in recurrence would improve patient outcomes and reduce cost and stone morbidities.Our objective was to review results of experimental studies performed to determine the efficacy of readily available compounds that can be used to prevent recurrence.Methods: All relevant literature up to October 2020,listed in PubMed is reviewed.Results: Clinical guidelines endorse the use of evidence-based medications,such as alkaline agents and thiazides,to reduce urinary mineral supersaturation and recurrence.However,there may be additional steps during stone pathogenesis where medications could moderate stone risk.Idiopathic calcium oxalate stones grow attached to Randall’s plaques or plugs.Results of clinical and experimental studies suggest involvement of reactive oxygen species and oxidative stress in the formation of both the plaques and plugs.The renin-angiotensin-aldosterone system(RAAS),nicotinamide adenine dinucleotide phosphate(NADPH)oxidase,mitochondria,and NOD-like receptor pyrin domain containing-3(NLRP3)inflammasome have all been implicated at specific steps during stone pathogenesis in animal models.Conclusion: In addition to supersaturation-reducing therapies,the use of anti-oxidants,free radical scavengers,and inhibitors of NADPH oxidase,NLRP3 inflammasome,and RAAS may prove beneficial for stone prevention.Compounds such as statins and angiotensin converting enzyme inhibitors are already in use as therapeutics for hypertension and cardio-vascular disease and have previously shown to reduce calcium oxalate nephrolithiasis in rats.Although clinical evidence for their use in stone prevention in humans is limited,experimental data support they be considered along with standard evidence-based medications and clinical expertise when patients are being counselled for stone prevention. 展开更多
关键词 Kidney stones calcium oxalate Inflammation INFLAMMASOME SUPERSATURATION Reactive oxygen species Oxidative stress
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Crystalline-magnetism action in biomimetic mineralization of calcium carbonate
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作者 Chaoqun Wu Xun Liu +3 位作者 Fujun Yao Xin Yang Yan Wang Wenyuan Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期146-152,共7页
The influence of minor environmental factors,such as the geomagnetic field,on the biomineralization of nacres,is often ignored but a great deal of research has confirmed its important role in the normal mineralization... The influence of minor environmental factors,such as the geomagnetic field,on the biomineralization of nacres,is often ignored but a great deal of research has confirmed its important role in the normal mineralization of calcium carbonate.Although the geomagnetic field is weak,its cumulative effects need to be considered given that the biomineralization process can take years.Accordingly,the authors of this paper have investigated the effects of weak magnetic fields(25 Gs or 50 Gs)on calcium carbonate mineralization and analyzed the mechanism involved.The results show that even a weak magnetic field conduces to the formation of vaterite or aragonite,in the induction order of precursor→vaterite→aragonite.The stronger the magnetic field and the longer the time,the more obvious the induction effect.The effect of a magnetic field is strongest in the aging stage and weakest in the solution stage.Inductions by egg-white protein and by a magnetic field inhibit each other,but they both restrict particle growth.These findings highlight the importance of minor environmental factors for biomineralization and can serve as a reference for biomimetic preparation of a CaCO_(3)nacre-like structure and for anti-scale technology for circulating cooling water. 展开更多
关键词 Biomimetic mineralization calcium carbonate Magnetic field Egg-white protein
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Optimization of growth medium for microbially induced calcium carbonate precipitation(MICP) treatment of desert sand
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作者 Monika DAGLIYA Neelima SATYAM Ankit GARG 《Journal of Arid Land》 SCIE CSCD 2023年第7期797-811,共15页
Wind-induced sand erosion is a natural process, and can have several negative impacts on human health, environment, and economy. To mitigate the wind-induced sand erosion, an environmental friendly technique that help... Wind-induced sand erosion is a natural process, and can have several negative impacts on human health, environment, and economy. To mitigate the wind-induced sand erosion, an environmental friendly technique that helps to bind soil particles is desirable. The microbially induced calcium carbonate precipitation(MICP) treatment has lately become renowned and a viable alternative to enhance the binding of sand particles(especially against wind erosion). The efficiency of Sporosarcina pasteurii bacteria in inducing calcite formation can be influenced by various factors, including the type of growth media used for bacterial culture. Most of the studies have mainly validated the efficiency of S. pasteurii bacteria usually under single growth media for the MICP treatment. However, the efficiency of S. pasteurii under different growth media on calcite formation is rarely explored. The current study explores the effect of S.pasteurii bacteria on calcite formation under the presence of three different growth media, namely,molasses(MS), tryptic soy broth(TB), and nutrient broth(NB). The three growth media have been applied in the laboratory with and without bacterial solution(control samples). Altered cementation media concentrations(0.5 and 1.0 M) with different pore volumes(PVs), namely, 0.25, 0.50, and 1.00 PV were used in sand-filled tubes for 7 and 14 treatment cycles(1 cycle=24 h). The pH and EC were measured for 12-h period in every 2 h interval, to monitor values at the time of treatment at room temperature. The calcite precipitation was confirmed using SEM(scanning electron microscope), PXRD(powder X-ray diffraction), and calcimeter tests. It was observed that MS generates lower calcite precipitation as compared with NB and TB. However, MS has the advantage of being more economical and abundant(waste product from sugar mills and refineries) as compared with other growth media(NB and TB). It was observed that the minimum and the maximum calcite precipitation using MS is 5% and 12%, respectively.The findings using MS in the present study was compared with the literature and found that precipitation of calcite using MS is effective to stabilize soil against wind erosion. 展开更多
关键词 growth media MOLASSES tryptic soy broth nutrient broth S.pasteurii calcium carbonate
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Structure, Formation, Properties, and Application of Calcium and Magnesium Silicate Hydrates System—A Review
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作者 肖建敏 LI Hui HU Yaru 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期604-615,共12页
In order to expand the advantages of strong durability and high compressive strength of calcium silicate hydrates(C-S-H),at the same time to make up for the poor early mechanical strength of magnesium silicate hydrate... In order to expand the advantages of strong durability and high compressive strength of calcium silicate hydrates(C-S-H),at the same time to make up for the poor early mechanical strength of magnesium silicate hydrates (M-S-H),we present the features and advantages of C-S-H and M-S-H and a comprehensive review of the progress on CaO-MgO-SiO_(2)-H_(2)O.Moreover,we systematically describe natural calcium and magnesium silicate minerals and thermodynamic properties of CaO-MgO-SiO_(2)-H_(2)O.The effect of magnesium on C-S-H and calcium on M-S-H is summarized deeply;the formation and structural feature of CaO-MgO-SiO_(2)-H_(2)O is also explained in detail.Finally,the development of calcium and magnesium silicate hydrates in the future is pointed out,and the further research is discussed and estimated. 展开更多
关键词 calcium and magnesium silicate hydrates thermodynamic properties STABILITY structural feature
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A Primary Study on Mechanical Properties of Heat-Treated Wood via in-situ Synthesis of Calcium Carbonate
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作者 Dianen Liang Zhenhao Ding +8 位作者 Qilin Yan Redžo Hasanagić Leila Fathi Zi Yang Longhao Li Jianbo Wang Houhua Luo Qian Wang Demiao Chu 《Journal of Renewable Materials》 SCIE EI 2023年第1期435-451,共17页
This study aims to improve the value of fast-growing wood and extend the heat-treated wood utilization using inorganic calcium carbonate(CaCO_(3))crystals via an in-situ synthesis method.CaCl_(2)and Na 2CO_(3)solution... This study aims to improve the value of fast-growing wood and extend the heat-treated wood utilization using inorganic calcium carbonate(CaCO_(3))crystals via an in-situ synthesis method.CaCl_(2)and Na 2CO_(3)solutions with a concentration ratio of 1:1 were successively introduced into the thermally modified poplar wood obtained by steam heat treatment(HT)at 200℃for 1.5 and 3 h,resulting in the in-situ synthesis of CaCO_(3)crystals inside the heat-treated wood.The filling effect was best at the concentration of 1.2 mol/L.CaCO_(3)was uniformly distributed in the cell cavities of the heat-treated wood,and some of the crystals were embedded in the fissures of the wood cell walls.The morphology of CaCO_(3)crystals was mainly spherical and rhombic polyhedral.Three main types of CaCO_(3)crystals were calcite,vaterite,and aragonite.The HT of poplar wood at 200℃resulted in degrading the chemical components of the wood cell wall.This degradation led to reduced wood mechanical properties,including the surface hardness(HD),modulus of rupture(MOR),and modulus of elasticity(MOE).After CaCO_(3)was in-situ synthesized in the heat-treated wood,the HD increased by 18.36%and 16.35%,and MOR increased by 14.64%and 8.89%,respectively.Because of the CaCO_(3)synthesization,the char residue of the 200℃heat-treated wood samples increased by 9.31%and the maximum weight loss rate decreased by 19.80%,indicating that the filling with CaCO_(3)cannot only improve the mechanical properties of the heat-treated wood but also effectively enhance its thermal stability. 展开更多
关键词 Heat treatment poplar wood calcium carbonate in-situ synthesis REINFORCEMENT
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