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Efficient synthesis of hydroxyl functioned polyesters from natural polyols and sebacic acid 被引量:5
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作者 Zhuo Yuan Ning Qing Shan Zhang Qin Pei Wu Yun Zheng Li Dong Xia Ma Jia Zhe Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第6期635-638,共4页
Amphiphilic hydroxyl functioned polyester(HFP) can be used as compatibilizers for blends of starch and resins.We developed a synthetic method for effective preparation of HFPs.Water was removed by high flow rate N_2... Amphiphilic hydroxyl functioned polyester(HFP) can be used as compatibilizers for blends of starch and resins.We developed a synthetic method for effective preparation of HFPs.Water was removed by high flow rate N_2 rather than high vacuum during polycondensation of sebacic acid with xylitol,sorbitol,or mannitol in the presence of dehydrative condensation catalyst and the product is with[η]of 27.2 mL/g,M_n of 1903,M_w of 167,693,T_g of -30.5℃,T_m of 44.0℃.Weight loss is 1.73%under 200℃. The integral distributions of molecular weight are 43.6 wt%and 63.8 wt%over 10,000 and 3000,respectively.The results indicated that higher molecular weight HFP was economically synthesized. 展开更多
关键词 Hydroxyl functioned polyester Poly(sorbitol sebacate) Dehydrative condensation catalyst Biodegradable plastics
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 被引量:2
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 ANGIOGENESIS apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation MICROGLIA motor function spinal cord injury vascular endothelial growth factor
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The Analysis of Gauss Radial Basis Functions and Its Application in Locating Olivine on the Moon
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作者 SONG Shicang SONG Xiaoyuan SONG Shuhan 《应用数学》 北大核心 2026年第1期173-181,共9页
Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the m... Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the main contributions is proving this property using linear algebra instead of profound knowledge.This makes it easy to read and understand this fundamental fact.The proof of linear independence of a set of Gauss functions relies on the constructing method for one-dimensional space and on the deducing method for higher dimensions.Additionally,under the condition of preserving the same moments between the original function and interpolating function,both the interpolating existence and uniqueness are proven for GRBF in one-dimensional space.The final work demonstrates the application of the GRBF method to locate lunar olivine.By combining preprocessed data using GRBF with the removing envelope curve method,a program is created to find the position of lunar olivine based on spectrum data,and the numerical experiment shows that it is an effective scheme. 展开更多
关键词 Gauss function Radial basis function Machine learning Lunar olivine locating Data fitting
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Some Reciprocity Formulas for Generalized Dedekind-Rademacher Sums
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作者 HE Yuan SHI Yongguo 《数学进展》 北大核心 2026年第1期85-102,共18页
In this paper,we study the generalized Dedekind Rademacher sums considered by Hall,Wilson and Zagier.We establish a new formula for the products of two Bernoulli functions by using Parseval's formula,Hurwitz's... In this paper,we study the generalized Dedekind Rademacher sums considered by Hall,Wilson and Zagier.We establish a new formula for the products of two Bernoulli functions by using Parseval's formula,Hurwitz's formula and Lerch's functional equation.As applications of the result,some well-known reciprocity formulas are deduced as special cases. 展开更多
关键词 Bernoulli function Dedekind sum Hurwitz and Lerch zeta function reciprocity formula
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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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Theoretical insights into the hydrogen peroxide oxidation and reduction reactions on low-index Pt surfaces
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作者 WANG Qi CHEN Lifang +1 位作者 DING Ruimin YIN Xi 《燃料化学学报(中英文)》 北大核心 2026年第1期35-45,共11页
Hydrogen peroxide(H_(2)O_(2))oxidation and reduction reactions(HPOR/HPRR)are pivotal in various innovative electrochemical energy conversion devices.A comprehensive understanding of these mechanisms is critical for ca... Hydrogen peroxide(H_(2)O_(2))oxidation and reduction reactions(HPOR/HPRR)are pivotal in various innovative electrochemical energy conversion devices.A comprehensive understanding of these mechanisms is critical for catalyst design and performance improvement in these applications.In this work,we systematically investigate the HPOR/HPRR mechanisms on low-index Pt surfaces,specifically Pt(111),Pt(100)and Pt(110),through density functional theory(DFT)calculations combined with the computational hydrogen electrode(CHE)model.For HPOR,all the low-index Pt surfaces exhibit a unified potential-determining step(PDS)involving the electrochemical oxidation of hydroperoxyl intermediates(HOO*).The binding free energy of HOO*(Δ_(GHOO*))emerges as an activity descriptor,with Pt(110)exhibiting the highest HPOR activity.The HPRR mechanism follows a chem-electrochemical(C-EC)pathway.The rate-determining step(RDS)of HPRR is either the cleavage of the HO-OH bond(chemical)or the reduction of HO(electrochemical),depending on their respective activation energies.These activation energies are functions of the HO*binding free energy,Δ_(GHO*),establishingΔ_(GHO*)as the descriptor for HPRR activity prediction.Pt(111)and Pt(100)are identified as the most active HPRR catalysts among the studied metal surfaces,although they still experience a significant overpotential.The scaling relationship betweenΔ_(GHOO*)andΔ_(GHO*)reveals a thermodynamic coupling of HPOR and HPRR,explaining their occurrence on Pt surfaces.These findings provide important insights and activity descriptors for both HPOR and HPRR,providing valuable guidance for the design of electrocatalysts in H_(2)O_(2)-related energy applications and fuel cells. 展开更多
关键词 HPOR HPRR Pt low-index surfaces density functional theory
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Post-synthetic modification strategy to construct Co-MOF composites for boosting oxygen evolution reaction activity
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作者 ZHENG Haifeng GUO Xingzhe +5 位作者 WEI Yunwei WANG Xinfang QI Huimin YAN Yuting ZHANG Jie LI Bingwen 《无机化学学报》 北大核心 2026年第1期193-202,共10页
The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecul... The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276. 展开更多
关键词 PYRENE metal-organic frameworks composite catalyst oxygen evolution reaction density functional theory
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Theoretical study on the thermally activated delayed fluorescence,and efficiency roll‑off characteristics of a series of blue and blue‑green Ir(Ⅲ)complexes
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作者 QIN Zhengkun BAO Lixin +4 位作者 ZHANG Yunkai CUI Lin WANG Jinyu WANG Yuhao SONG Mingxing 《无机化学学报》 北大核心 2026年第2期365-374,共10页
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc... A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine. 展开更多
关键词 organic light‑emitting diodes Ir(Ⅲ)complex time‑dependent density functional theory thermal activation delayed fluorescence property efficiency roll‑off effect
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Are emerging electroconductive biomaterials for spinal cord injury repair the future?
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作者 Aleksandra Serafin Maurice N.Collins 《Neural Regeneration Research》 2026年第3期1140-1141,共2页
Spinal cord injury(SCI)is a debilitating ailment that leads to the loss of motor and sensory functions,often leaving the patient paralyzed below the injury site(Chen et al.,2013).Globally around 250,000-300,000 people... Spinal cord injury(SCI)is a debilitating ailment that leads to the loss of motor and sensory functions,often leaving the patient paralyzed below the injury site(Chen et al.,2013).Globally around 250,000-300,000 people are diagnosed with SCI annually(Singh et al.,2014),and while this number appears quite low,the effect that an SCI has on the patient’s quality of life is drastic,due to the current difficulties to comprehensively treat this illness.The cost of patient care can also be quite costly,amounting to an estimated$1.69 billion in healthcare costs in the USA alone(Mahabaleshwarkar and Khanna,2014). 展开更多
关键词 spinal cord injury PARALYSIS electroconductive biomaterials healthcare costs sensory functions motor functions repair spinal cord injury sci
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Using mixed kernel support vector machine to improve the predictive accuracy of genome selection
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作者 Jinbu Wang Wencheng Zong +6 位作者 Liangyu Shi Mianyan Li Jia Li Deming Ren Fuping Zhao Lixian Wang Ligang Wang 《Journal of Integrative Agriculture》 2026年第2期775-787,共13页
The advantages of genome selection(GS) in animal and plant breeding are self-evident.Traditional parametric models have disadvantage in better fit the increasingly large sequencing data and capture complex effects acc... The advantages of genome selection(GS) in animal and plant breeding are self-evident.Traditional parametric models have disadvantage in better fit the increasingly large sequencing data and capture complex effects accurately.Machine learning models have demonstrated remarkable potential in addressing these challenges.In this study,we introduced the concept of mixed kernel functions to explore the performance of support vector machine regression(SVR) in GS.Six single kernel functions(SVR_L,SVR_C,SVR_G,SVR_P,SVR_S,SVR_L) and four mixed kernel functions(SVR_GS,SVR_GP,SVR_LS,SVR_LP) were used to predict genome breeding values.The prediction accuracy,mean squared error(MSE) and mean absolute error(MAE) were used as evaluation indicators to compare with two traditional parametric models(GBLUP,BayesB) and two popular machine learning models(RF,KcRR).The results indicate that in most cases,the performance of the mixed kernel function model significantly outperforms that of GBLUP,BayesB and single kernel function.For instance,for T1 in the pig dataset,the predictive accuracy of SVR_GS is improved by 10% compared to GBLUP,and by approximately 4.4 and 18.6% compared to SVR_G and SVR_S respectively.For E1 in the wheat dataset,SVR_GS achieves 13.3% higher prediction accuracy than GBLUP.Among single kernel functions,the Laplacian and Gaussian kernel functions yield similar results,with the Gaussian kernel function performing better.The mixed kernel function notably reduces the MSE and MAE when compared to all single kernel functions.Furthermore,regarding runtime,SVR_GS and SVR_GP mixed kernel functions run approximately three times faster than GBLUP in the pig dataset,with only a slight increase in runtime compared to the single kernel function model.In summary,the mixed kernel function model of SVR demonstrates speed and accuracy competitiveness,and the model such as SVR_GS has important application potential for GS. 展开更多
关键词 genome selection machine learning support vector machine kernel function mixed kernel function
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Artificial intelligence in functional gastrointestinal disorders:From precision diagnosis to preventive healthcare
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作者 Yi-Nan Yan Jing-Qi Zeng Xia Ding 《Artificial Intelligence in Gastroenterology》 2026年第1期20-35,共16页
Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to s... Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to symptom heterogeneity and the absence of reliable biomarkers.Artificial intelligence(AI)enables the integration of multimodal data to enhance FGID management through precision diagnostics and preventive healthcare.This minireview summarizes recent advancements in AI applications for FGIDs,highlighting progress in diagnostic accuracy,subtype classification,personalized interventions,and preventive strategies inspired by the traditional Chinese medicine concept of“treating the undiseased”.Machine learning and deep learning algorithms have demonstrated value in improving IBS diagnosis,refining FD neuro-gastrointestinal subtyping,and screening for GERD-related complications.Moreover,AI supports dietary,psychological,and integrative medicine-based interventions to improve patient adherence and quality of life.Nonetheless,key challenges remain,including data heterogeneity,limited model interpretability,and the need for robust clinical validation.Future directions emphasize interdisciplinary collaboration,the development of multimodal and explainable AI models,and the creation of patientcentered platforms to facilitate a shift from reactive treatment to proactive prevention.This review provides a systematic framework to guide the clinical application and theoretical innovation of AI in FGIDs. 展开更多
关键词 Artificial intelligence Functional gastrointestinal disorders Irritable bowel syndrome Functional dyspepsia Gastroesophageal reflux disease
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IMPROVEMENT ON HANKEL DETERMINANT BOUNDS FOR SPECIFIC HOLOMORPHIC FUNCTIONS
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作者 Huo TANG Muhammad ABBAS +1 位作者 Reem K.ALHEFTHI Muhammad ARIF 《Acta Mathematica Scientia》 2026年第1期39-61,共23页
In recent years,researchers have extensively investigated the Hankel determinant,which consists of coefficients appearing in a holomorphic function’s Taylor-Maclaurin series.Hankel matrices are widely used in Markov ... In recent years,researchers have extensively investigated the Hankel determinant,which consists of coefficients appearing in a holomorphic function’s Taylor-Maclaurin series.Hankel matrices are widely used in Markov processes,non-stationary signals,and other mathematical disciplines.The aim of the current research article is to first improve the bounds of coefficient-related problems by employing the well-known Carathéodory function.The problems that we are going to improve were obtained by Tang et al.The sharp estimates of the most difficult problem of geometric function theory known as the third-order Hankel determinant are also contributed here.Zalcman and Fekete-Szegöinequalities are also studied here for the defined family of holomorphic functions. 展开更多
关键词 holomorphic function Carathéodory function Hankel determinant Zalcman inequality
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Extra-pineal melatonin in perisynaptic Schwann cell–muscle fiber cross talk at the regenerating neuromuscular junction
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作者 Samuele Negro Cesare Montecucco Michela Rigoni 《Neural Regeneration Research》 2026年第1期300-301,共2页
The neuromuscular junction and its proregenerative niche:The mammalian peripheral nervous system,unlike the central nervous system,has preserved throughout evolution the ability to regenerate and fully restore functio... The neuromuscular junction and its proregenerative niche:The mammalian peripheral nervous system,unlike the central nervous system,has preserved throughout evolution the ability to regenerate and fully restore function.Key factors for effective nerve regeneration include a supportive neuronal environment and a coordinated tissue response(Brosius Lutz and Barres,2014). 展开更多
关键词 FUNCTION SYSTEM COORDINATED
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Functional genes associated with the occurrence of mycotoxins produced by Aspergillus in foods
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作者 Mei Gu Can Liu +4 位作者 Xiaofeng Yue Du Wang Xiaoqian Tang Qi Zhang Peiwu Li 《Journal of Integrative Agriculture》 2026年第2期585-601,共17页
Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural pro... Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural products,thereby endangering human health.Extensive studies on Aspergillus fungi have been conducted on growth and development,aflatoxin biosynthesis,and their interactions with environment.Here,we summarized a series of functional genes of the main Aspergillus fungi relative to toxins occurrence in foods,which revealed the signal transduction mechanisms of their involvement in growth and development,toxin production,and response to light,anticipating providing theoretical guidance on developing control and prevention technologies for mycotoxin contamination in agricultural products to ensure food safety. 展开更多
关键词 functional genes ASPERGILLUS AFLATOXIN DEVELOPMENT
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Pericyte-glial cell interactions: Insights into brain health and disease
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作者 Ali Sepehrinezhad Ali Gorji 《Neural Regeneration Research》 2026年第4期1253-1263,共11页
Pericytes are multi-functional mural cells of the central nervous system that cover the capillary endothelial cells. Pericytes play a vital role in nervous system development, significantly influencing the formation, ... Pericytes are multi-functional mural cells of the central nervous system that cover the capillary endothelial cells. Pericytes play a vital role in nervous system development, significantly influencing the formation, maturation, and maintenance of the central nervous system. An expanding body of studies has revealed that pericytes establish carefully regulated interactions with oligodendrocytes, microglia, and astrocytes. These communications govern numerous critical brain processes, including angiogenesis, neurovascular unit homeostasis, blood–brain barrier integrity, cerebral blood flow regulation, and immune response initiation. Glial cells and pericytes participate in dynamic and reciprocal interactions, with each influencing and adjusting the functionality of the other. Pericytes have the ability to control astrocyte polarization, trigger differentiation of oligodendrocyte precursor cells, and initiate immunological responses in microglia. Various neurological disorders that compromise the integrity of the blood–brain barrier can disrupt these communications, impair waste clearance, and hinder cerebral blood circulation, contributing to neuroinflammation. In the context of neurodegeneration, these disruptions exacerbate pathological processes, such as neuronal damage, synaptic dysfunction, and impaired tissue repair. This article explores the complex interactions between pericytes and various glial cells in both healthy and pathological states of the central nervous system. It highlights their essential roles in neurovascular function and disease progression, providing important insights that may enhance our understanding of the molecular mechanisms underlying these interactions and guide potential therapeutic strategies for neurodegenerative disorders in future research. 展开更多
关键词 BRAIN INFLAMMATION NEUROPROTECTION neurovascular function therapeutic targets
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Csp^(2)-H functionalization as an efficient catalytic route to carbazoles
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作者 Giulia Brufani Edoardo Bazzica +2 位作者 Yanlong Gu Francesco Mauriello Luigi Vaccaro 《Chinese Chemical Letters》 2026年第1期39-56,共18页
Given the broad applicability of carbazole structural moieties in materials science and medicinal chemistry,significant efforts have been devoted to developing efficient synthetic catalytic methodologies to access thi... Given the broad applicability of carbazole structural moieties in materials science and medicinal chemistry,significant efforts have been devoted to developing efficient synthetic catalytic methodologies to access this valuable scaffold.Catalyzed direct Csp^(2)-H functionalization provides an effective and costefficient approach to synthesizing carbazoles from simple and readily available starting materials,ensuring a promising path characterized by excellent atom and step economy.This review highlights the substantial progress made in the last 10 years in advancing catalytic Csp^(2)-H functionalization techniques for synthesizing carbazoles. 展开更多
关键词 C-H functionalization CARBAZOLES Synthetic methodologies CATALYSIS
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Phosphodiesterase 4 regulates pyroptosis in subarachnoid hemorrhage
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作者 Jiahe Tan Yinrui Ma +3 位作者 Rui Song Hongjiang Ye Jun Su Zhaohui He 《Neural Regeneration Research》 2026年第6期2609-2620,共12页
Phosphodiesterase 4 is a key enzyme involved in the regulation of cell signal transduction,but its role in subarachnoid hemorrhage remains unclear.Neuronal pyroptosis has been reported to be involved in early brain in... Phosphodiesterase 4 is a key enzyme involved in the regulation of cell signal transduction,but its role in subarachnoid hemorrhage remains unclear.Neuronal pyroptosis has been reported to be involved in early brain injury after subarachnoid hemorrhage.This study aimed to investigate whether phosphodiesterase 4 contributes to early brain injury after subarachnoid hemorrhage by mediating neuronal pyroptosis and its related mechanisms.Endovascular perforation of male C57BL/6J mice was performed to model subarachnoid hemorrhage in vivo,and oxyhemoglobin was added to the culture medium of primary neurons to model subarachnoid hemorrhage in vitro.A phosphodiesterase 4-specific inhibitor,etazolate,was intraperitoneally injected 30 minutes after subarachnoid hemorrhage induction.Small interfering RNA(siRNA)was administered intracerebroventricularly 72 hours before subarachnoid hemorrhage to achieve genetic knockdown of phosphodiesterase 4.To investigate the mechanism,a nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3(NLRP3)-specific agonist,nigericin,was intracerebroventricularly injected 60 minutes before subarachnoid hemorrhage.Neuronal phosphodiesterase 4 expression increased after subarachnoid hemorrhage and reached the highest point at 24 hours.Etazolate treatment reduced neurological deficits and brain edema in mice,alleviated neuronal pyroptosis and inflammatory response,and improved neuronal injury.Treatment with phosphodiesterase 4 siRNA had the same neuroprotective effects as etazolate.Mechanistically,phosphodiesterase 4 triggered the nuclear factor kappa-B pathway,and simultaneously caused lysosomal and mitochondrial dysfunction after subarachnoid hemorrhage,which promoted NLRP3 inflammasome activation and induced neuronal pyroptosis.Blocking of phosphodiesterase 4 inhibited the nuclear factor kappa-B pathway,and improved lysosome and mitochondrial function.Activation of NLRP3 reversed the neuroprotective effects of etazolate without affecting phosphodiesterase 4 expression.Together,the results indicate that phosphodiesterase 4 regulates NLRP3-mediated neuronal pyroptosis in early brain injury after subarachnoid hemorrhage.Phosphodiesterase 4 may be a potential therapeutic molecular target for subarachnoid hemorrhage. 展开更多
关键词 early brain injury etazolate lysosome function mitochondrial function NEURON nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3(NLRP3) nuclear factor kappa-B phosphodiesterase 4 PYROPTOSIS subarachnoid hemorrhage
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Targeting gangliosides to treat Alzheimer’s and Parkinson’s diseases:A disruptive approach with the first-in-class peptide AmyP53
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作者 Jacques Fantini Nouara Yahi 《Neural Regeneration Research》 2026年第6期2339-2340,共2页
Neurodegenerative diseases are a growing burden on healthcare systems.Patients with Alzheimer’s or Parkinson’s diseases(AD or PD)are desperately waiting for innovative solutions that are slow to come,despite several... Neurodegenerative diseases are a growing burden on healthcare systems.Patients with Alzheimer’s or Parkinson’s diseases(AD or PD)are desperately waiting for innovative solutions that are slow to come,despite several decades of research worldwide.In 2021 and again in 2023,two monoclonal antibodies,aducanumab and lecanemab,have been approved by the U.S.Food and Drug Administration,and a third,donanemab,is currently under review.However,these treatments have very limited efficacy on cognitive functions and are accompanied by major side effects:amyloid-related imaging abnormalities,microhemorrhages,and accelerated brain volume loss(Høilund-Carlsen et al.,2024). 展开更多
关键词 neurodegenerative diseases cognitive functions ALZHEIMERS monoclonal antibodiesaducanumab PEPTIDE PARKINSONS diseases GANGLIOSIDES
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Protective effect of Guanxinning on antipsychotic-induced cardiac impairment in long-term hospitalized psychiatric patients
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作者 Fu-Gang Luo Hao-Yu Xing +4 位作者 Jun-Jie Wang Wen-Ye Wu Kai-Jie Fang Hai-Dong Song Juan Yan 《World Journal of Psychiatry》 2026年第1期221-232,共12页
BACKGROUND Long-term antipsychotic therapy in psychiatric patients carries significant cardiovascular risks,including QT interval prolongation,myocardial injury,and functional impairment.Guanxinning,a traditional Chin... BACKGROUND Long-term antipsychotic therapy in psychiatric patients carries significant cardiovascular risks,including QT interval prolongation,myocardial injury,and functional impairment.Guanxinning,a traditional Chinese medicine formulation,has demonstrated cardioprotective potential in preclinical studies,but clinical evidence in this population remains limited.AIM To evaluate the cardioprotective effects of Guanxinning against antipsychotic-induced cardiac injury in long-term hospitalized psychiatric patients.METHODS A randomized,double-blind,placebo-controlled trial was conducted with 120 psychiatric inpatients receiving chronic antipsychotic therapy.Participants were allocated to:Intervention group:Conventional antipsychotics+Guanxinning tablets(0.38 g×4 tablets,ter in die);Control group:Conventional antipsychotics+identical placebo;Cardiac assessments at baseline and 12 months included:Electrocardiography(corrected QT interval),echocardiography(left ventricular ejection fraction,left ventricular end-diastolic diameter),serum biomarkers(cardiac troponin I,B-type natriuretic peptide,superoxide dismutase,malondialdehyde,high-sensitivity C-reactive protein).RESULTS Compared to controls,the Guanxinning group showed:Electrophysiological improvement:Corrected QT shortening(438±25 milliseconds vs 465±30 milliseconds,P<0.01).Functional enhancement:Left ventricular ejection fraction increase(58.5%±5.2%vs 53.8%±4.8%,P<0.05),left ventricular end-diastolic diameter reduction(49.8±3.5 mm vs 52.6±3.8 mm,P<0.05),Biochemical modulation:Reduced myocardial injury markers(cardiac troponin I:0.009 ng/mL vs 0.014 ng/mL;B-type natriuretic peptide:52 pg/mL vs 78 pg/mL,P<0.001),improved oxidative stress(superoxide dismutase:↑13.3 U/mL;malondialdehyde:↓0.9 nmol/mL,P<0.001),attenuated inflammation(high-sensitivity C-reactive protein:2.0 mg/L vs 3.2 mg/L,P<0.001).CONCLUSION Guanxinning significantly mitigates antipsychotic-induced cardiac injury in psychiatric patients,demonstrating:Normalization of electrophysiological parameters,Preservation of systolic/diastolic function,suppression of oxidative stress and inflammation.These findings support its clinical application as an adjunctive cardioprotective therapy,potentially through inhibition of myocardial apoptosis and antioxidant upregulation. 展开更多
关键词 GUANXINNING Antipsychotic drugs Cardiac function SCHIZOPHRENIA Cardiac protection
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Melatonin:a key player in alleviating heavy metal stress in plants―current insights and future directions
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作者 Wenhan Dong 《Horticultural Plant Journal》 2026年第1期36-48,共13页
Heavy metal(HM)contamination severely impacts global agricultural production.HMs toxicity effectively damaged the physiological functions such as imbalanced redox homeostasis,altered antioxidant enzyme activity,damage... Heavy metal(HM)contamination severely impacts global agricultural production.HMs toxicity effectively damaged the physiological functions such as imbalanced redox homeostasis,altered antioxidant enzyme activity,damage root system architecture,hindered photosynthetic apparatus,cellular toxicity,restricted mineral accumulation,and changed the metabolite production.Using phytohormones may be a successful strategy for enhancing and stimulating plant tolerance to HMs toxicity without affecting the environment.Melatonin(MT),a novel plant growth regulator,and powerful antioxidant molecule,enhances plant resilience to HMs stress by enhancing seedling growth,protecting the photosynthetic system,increasing nutritional status,balanced redox homeostasis,and restricting HMs accumulation from root to shoot.In addition,MT enhances the activity of antioxidant enzymes and triggers the ascorbate-glutathione(AsA-GSH)cycle,which helps remove excessive ROS.MT improves RuBisCO activity to improve photosynthesis and reduce the breakdown of chlorophyll.To identify future research needs,it is crucial to understand the comprehensive and intricate regulatory mechanisms of exogenous and endogenous MT-mediated reduction of heavy metal toxicity in plants.Melatonin has several functions,and this review sheds light on those functions and the molecular processes by which it alleviates HMs toxicity.More research is needed to fully understand how melatonin affects plant tolerance to heavy metals stress. 展开更多
关键词 MELATONIN Heavy metals PHOTOSYNTHESIS Cell wall Cellular function Stress management
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