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Fuzzy Dynamic Optimal Model for COVID-19 Epidemic in India Based on Granular Differentiability
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作者 KHATUA Debnarayan DE Anupam +3 位作者 KAR Samarjit SAMANTA Eshan SEKH Arif Ahmed GUHA ADHYA Debashree 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期545-560,共16页
The pandemic SARS-CoV-2 has become an undying virus to spread a sustainable disease named COVID-19 for upcoming few years.Mortality rates are rising rapidly as approved drugs are not yet available.Isolation from the i... The pandemic SARS-CoV-2 has become an undying virus to spread a sustainable disease named COVID-19 for upcoming few years.Mortality rates are rising rapidly as approved drugs are not yet available.Isolation from the infected person or community is the preferred choice to protect our health.Since humans are the only carriers,it might be possible to control the positive rate if the infected population or host carriers are isolated from each other.Isolation alone may not be a proper solution.These are the resolutions of previous research work carried out on COVID-19 throughout the world.The present scenario of the world and public health is knocking hard with a big question of critical uncertainty of COVID-19 because of its imprecise database as per daily positive cases recorded all over the world and in India as well.In this research work,we have pre-sented an optimal control model for COVID-19 using granular differentiability based on fuzzy dynamical systems.In the first step,we created a fuzzy Susceptible-Exposed-Infected-Asymptomatic-Hospitalized-Recovered-Death(SEIAHRD)model for COVID-19,analyzed it using granular differentiability,and reported disease dynamics for time-independent disease control parameters.In the second step,we upgraded the fuzzy dynamical system and granular differentiability model related to time-dependent disease control parameters as an optimal control problem invader.Theoretical studies have been validated with some practical data from the epidemic COVID-19 related to the Indian perspective during first wave and early second wave. 展开更多
关键词 COVID-19 ASYMPTOMATIC SUSCEPTIBLE fuzzy dynamical system granular differentiability
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GÂTEAUX DIRECTIONAL DIFFERENTIABILITY OF THE GENERALIZED METRIC PROJECTION IN BANACH SPACES
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作者 Jinlu LI 《Acta Mathematica Scientia》 2025年第4期1597-1618,共22页
Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this pap... Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this paper,we define the Gâteaux directional differentiability of Π_(C).We investigate some properties of the Gâteaux directional differentiability of Π_(C).In particular,if C is a closed ball,or a closed and convex cone(including proper closed subspaces),or a closed and convex cylinder,then,we give the exact representations of the directional derivatives of Π_(C).By comparing the results in[12]and this paper,we see the significant difference between the directional derivatives of the generalized metric projection operator Π_(C) and the Gâteaux directional derivatives of the standard metric projection operator PC. 展开更多
关键词 uniformly convex and uniformly smooth Banach space the generalized metric projection directional differentiability of the generalized metric projection directional derivative of the generalized metric projection
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带有异质信息顾客和差异化休假的排队系统最优策略
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作者 田瑞玲 宋涛 +2 位作者 黄艳玲 王腾 陈小娟 《应用数学》 北大核心 2026年第1期198-208,共11页
本文研究了带有异质信息顾客和差异化休假的排队系统.当系统为空时,服务台开始休假,休假回来后如果系统中有顾客等待则进入忙期.否则服务台将进行多重休假直到某次休假回来系统中有顾客存在.到达顾客根据被告知信息程度的不同分为完全... 本文研究了带有异质信息顾客和差异化休假的排队系统.当系统为空时,服务台开始休假,休假回来后如果系统中有顾客等待则进入忙期.否则服务台将进行多重休假直到某次休假回来系统中有顾客存在.到达顾客根据被告知信息程度的不同分为完全告知顾客和完全不告知顾客.本文首先通过构建差分方程解平衡方程,获得系统稳态概率及性能指标.然后考虑顾客均衡和社会最优两种情况,对完全告知顾客求解阈值策略,对完全不告知顾客求解其混合加入策略.之后通过数值分析考察参数对顾客策略及社会收益的影响.本文考虑更复杂的现实,希望能丰富对排队问题的研究. 展开更多
关键词 异质信息 差异化休假 均衡策略 社会最优收益 排队
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支农政策促进农民职业分化了吗?——基于灰熵模型及政策组态的研究
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作者 李逸波 王卓 《河北经贸大学学报》 北大核心 2026年第1期30-41,共12页
惠政兴三农,农民职业分化水平的提升离不开三农政策的支撑。基于2000-2024年中国支农政策与农民职业分化相关数据,综合运用灰关联熵模型与模糊集定性比较分析(fsQCA)两种方法进行实证分析。研究发现:支农政策对农民职业分化的推动作用... 惠政兴三农,农民职业分化水平的提升离不开三农政策的支撑。基于2000-2024年中国支农政策与农民职业分化相关数据,综合运用灰关联熵模型与模糊集定性比较分析(fsQCA)两种方法进行实证分析。研究发现:支农政策对农民职业分化的推动作用在观测期内整体显著,其中农村发展政策影响最大,农民就业政策与培育保障政策次之,人口流动与户籍政策相对较小,且地方政策的促进作用略高于中央政策;fsQCA组态分析进一步揭示出四种能有效促进农民职业分化的政策组合模式,分别为中央推动型、地方发力型、发展保障型与全面促进型。结果表明,支农政策是驱动农民职业分化的关键系统力量,其效果取决于不同政策工具的协同组合与央地联动。 展开更多
关键词 支农政策 农民职业分化 灰关联熵 耗散结构理论 政策组态
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咳嗽变异性哮喘误诊原因及鉴别要点分析
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作者 姜锋 秦良楠 +1 位作者 杨林瀛 米术斌 《临床误诊误治》 2026年第1期7-11,共5页
目的 探讨咳嗽变异性哮喘(CVA)的临床特点、误诊原因及防范措施。方法 回顾性分析2022年6月至2024年6月收治曾误诊的10例CVA病例资料。结果 10例中男6例、女4例,年龄18~45岁。3例以持续性咳嗽伴少量白黏痰为主要表现,查体双肺未闻及明... 目的 探讨咳嗽变异性哮喘(CVA)的临床特点、误诊原因及防范措施。方法 回顾性分析2022年6月至2024年6月收治曾误诊的10例CVA病例资料。结果 10例中男6例、女4例,年龄18~45岁。3例以持续性咳嗽伴少量白黏痰为主要表现,查体双肺未闻及明显啰音,胸部X线检查示肺纹理增粗,初诊为慢性支气管炎,予抗感染及止咳治疗无效,后经支气管激发试验确诊为CVA。3例以反复咳嗽、流涕、鼻塞为主要表现,初诊为上呼吸道感染,予抗病毒及对症治疗无缓解,经肺功能检查及过敏原检测确诊为CVA。4例以刺激性干咳伴咽痒为主要表现,喉镜检查示咽部黏膜充血,初诊为慢性咽炎,治疗后症状反复,最终经支气管激发试验等检查确诊为CVA。本组10例的误诊时间为1~3个月。确诊后予吸入性糖皮质激素联合支气管舒张剂治疗,症状均显著改善。结论 CVA临床表现缺乏特异性,易与慢性支气管炎、上呼吸道感染及慢性咽炎混淆。临床医师应提高对CVA的认识,重视慢性咳嗽的鉴别诊断,及时行肺功能、支气管激发试验等检查,以减少误诊误治。 展开更多
关键词 咳嗽变异性哮喘 误诊 慢性支气管炎 上呼吸道感染 慢性咽炎 肺功能 鉴别诊断
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DIFFERENTIABILITY OF C_0-SEMIGROUPS WITH APPLICATION
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作者 金振东 喻文焕 +1 位作者 靳展 王辅敏 《Transactions of Tianjin University》 EI CAS 1999年第2期25-29,共5页
This paper considers the differentiability of C 0 semigroups with respect to (w.r.t.) parameters contained in their infinitesimal generators.It is proved that the generalized continuity and strong differentiability ... This paper considers the differentiability of C 0 semigroups with respect to (w.r.t.) parameters contained in their infinitesimal generators.It is proved that the generalized continuity and strong differentiability of their infinitesimal generators w.r.t.parameters imply the differentiability of the C 0 semigroups.The results are applied to the differentiability of the solution of a linear delay differential equation w.r.t.its delays. 展开更多
关键词 C 0 semigroup infinitesimal generator generalized continuity strongly Frechet differential dalay equation
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还原型氧化石墨烯提高脂肪干细胞内皮向分化效率及血管形成能力
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作者 姚金凤 邓梦昭 +2 位作者 谢添 陈瞰 王海霞 《中国组织工程研究》 北大核心 2026年第13期3270-3279,共10页
背景:脂肪干细胞能够在特定的诱导环境下分化为血管内皮细胞,是组织工程血管化过程中较为理想的种子细胞。然而脂肪干细胞的内皮向分化效率低,严重限制了该方法的应用。目的:探讨还原型氧化石墨烯对脂肪干细胞内皮向分化效率和血管形成... 背景:脂肪干细胞能够在特定的诱导环境下分化为血管内皮细胞,是组织工程血管化过程中较为理想的种子细胞。然而脂肪干细胞的内皮向分化效率低,严重限制了该方法的应用。目的:探讨还原型氧化石墨烯对脂肪干细胞内皮向分化效率和血管形成能力的影响。方法:首先,采用绿色合成工艺制备还原型氧化石墨烯,使用透射电镜、能谱分析和傅里叶变换红外光谱等手段对还原型氧化石墨烯进行材料表征。然后将不同质量浓度的还原型氧化石墨烯与脂肪干细胞共培养,通过CCK-8实验确定还原型氧化石墨烯的安全浓度范围,接着利用安全浓度范围内的还原型氧化石墨烯诱导脂肪干细胞内皮向分化,通过RT-qPCR和Western blot检测脂肪干细胞内皮向分化相关指标的表达。最后,通过划痕实验和小管形成实验评估还原型氧化石墨烯诱导分化后细胞的成管和迁移能力。结果与结论:①还原型氧化石墨烯具有典型的二维片状结构,主要含碳、氧元素,可检测到与含氧官能团相关的特征吸收峰;②CCK-8实验结果显示,10μg/mL及以下浓度的还原型氧化石墨烯培养72 h对脂肪干细胞的活力无影响;③RT-qPCR和Western blot结果显示,10μg/mL及以下浓度的还原型氧化石墨烯诱导6,9 d均可以显著提高脂肪干细胞内皮向分化相关标志物的表达,其中5μg/mL还原型氧化石墨烯诱导9 d,内皮向分化标志物基因表达差异最大;④划痕实验和小管形成实验结果表明,相较于空白组和对照组,还原型氧化石墨烯组细胞的迁移和成管能力显著增强;⑤结果表明,绿色合成的还原型氧化石墨烯可以显著提高脂肪干细胞的内皮向分化效率,其中5μg/mL还原型氧化石墨烯诱导9d是最佳的时间浓度组合,诱导分化后的细胞具有更好的血管形成功能。 展开更多
关键词 脂肪干细胞 还原型氧化石墨烯 绿色合成工艺 内皮向分化 血管生成 组织工程血管化
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McKean-Vlasov Backward Stochastic Differential Equations with Weak Monotonicity Coefficients
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作者 FU Zongkui FEI Dandan GUO Shanshan 《应用数学》 北大核心 2026年第1期98-107,共10页
This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic diff... This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic differential equations.Then we obtain a comparison theorem in one-dimensional situation. 展开更多
关键词 McKean-Vlasov backward stochastic differential equation Weak monotonicity condition Comparison theorem
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非创伤性股骨头坏死与脂质代谢的关系及治疗进展 被引量:1
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作者 周子翔 赵宝祥 《中国组织工程研究》 北大核心 2026年第3期680-690,共11页
背景:非创伤性股骨头坏死的发病机制尚不明确,其中血脂代谢紊乱是引起非创伤性股骨头坏死的重要假说,通过调节血脂代谢来抑制股骨头坏死的进展,已成为当前治疗非创伤性股骨头坏死的重要方法。目的:综述非创伤性股骨头坏死与脂质代谢紊... 背景:非创伤性股骨头坏死的发病机制尚不明确,其中血脂代谢紊乱是引起非创伤性股骨头坏死的重要假说,通过调节血脂代谢来抑制股骨头坏死的进展,已成为当前治疗非创伤性股骨头坏死的重要方法。目的:综述非创伤性股骨头坏死与脂质代谢紊乱的关系及治疗研究进展。方法:以“股骨头坏死,非创伤性股骨头坏死,骨坏死,骨与脂质代谢,股骨头坏死与脂质,股骨头坏死机制,股骨头坏死通路,股骨头坏死治疗”为中文检索词,以“osteonecrosis of femoral head,Nontraumatic osteonecrosis of femoral head,femoral head necrosis,osteonecrosis and lipid,lipid metabolism osteonecrosis,polymorphisms osteonecrosis of femoral head,pathway osteonecrosis of femoral head,steroid-induced osteonecrosis of the femoral head,alcohol-induced osteonecrosis of femoral head”为英文检索词,检索中国知网、万方医学网、中华医学期刊数据库、PubMed数据库,最终纳入104篇文献进行归纳总结。结果与结论:①股骨头坏死患者常伴随血脂异常,研究发现总胆固醇、三酰甘油、低密度脂蛋白胆固醇、载脂蛋白B水平升高与载脂蛋白A1水平降低是引起股骨头坏死的危险因素,并且不同诱因的股骨头坏死患者血脂水平存在差异;②激素和酒精作为非创伤性股骨头坏死的两大诱因,可以诱导骨髓间充质干细胞的成脂分化,使骨髓腔内脂肪细胞增多、脂滴聚集,最终导致股骨头坏死;③许多与脂质代谢相关的分子和脂肪因子,如脂联素、瘦素、脂质运载蛋白2等都被证实与股骨头坏死有关;④过氧化物酶体增殖物激活受体γ、Wnt/β-catenin、腺苷酸环化蛋白激酶等信号通路可以改变骨髓间充质干细胞的成骨-成脂分化潜能,从而参与股骨头坏死的发生发展;磷脂酰肌醇3激酶/蛋白激酶B、骨形态发生蛋白2等脂代谢信号通路也与股骨头坏死有关,可能通过调节脂质代谢影响股骨头坏死的进展;⑤研究发现,虫草素、三七总皂苷、骨蚀灵胶囊等中药和他汀类药物可以通过改善脂质代谢紊乱达到治疗非创伤性股骨头坏死的效果。 展开更多
关键词 股骨头坏死 脂质代谢 骨髓间充质干细胞 成骨分化 成脂分化 工程化组织构建
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New insights into the homeostatic role of Lrig1 in different neurogenic niches:Implications for neuronal regeneration
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作者 Ana Paula De Vincenti Fernanda Ledda Gustavo Paratcha 《Neural Regeneration Research》 2026年第4期1544-1545,共2页
Stem cell proliferation is tightly regulated in developing and adult tissues through the coordinated action of cell-intrinsic and extracellular signals.Although many extracellular cues were identified,the cell-intrins... Stem cell proliferation is tightly regulated in developing and adult tissues through the coordinated action of cell-intrinsic and extracellular signals.Although many extracellular cues were identified,the cell-intrinsic mechanisms underlying the decision of a stem cell to proliferate,enter a dormant quiescent state or differentiate into a specific cell type remains incompletely understood. 展开更多
关键词 neuronalregeneration neurogenicniches stem cell homeostaticrole dormant quiescent state differentiate specific cell type Lrig stemcellproliferation
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Sonazoid-contrast-enhanced ultrasound for the histological diagnosis of hepatocellular carcinoma
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作者 Ruo-Bing Liu Jun-Yi Xin +1 位作者 Zhe Huang Kai-Yan Li 《World Journal of Gastrointestinal Oncology》 2026年第1期122-134,共13页
BACKGROUND The treatment technology of liver cancer is progressing.In addition to traditional surgical resection,combined therapies of immunotherapy based on immune checkpoint inhibitors,chemotherapy,and transcatheter... BACKGROUND The treatment technology of liver cancer is progressing.In addition to traditional surgical resection,combined therapies of immunotherapy based on immune checkpoint inhibitors,chemotherapy,and transcatheter arterial chemoembolization for hepatocellular carcinoma are more and more widely used.Accurate preoperative diagnosis of liver cancer will provide important information for comprehensive treatment and prognosis evaluation of liver cancer.Sonazoidcontrast-enhanced ultrasound is not only helpful for the qualitative diagnosis of liver lesions,but also has great potential in the diagnosis of histological differentiation of liver cancer.AIM To assess the differentiation of hepatocellular carcinoma(HCC)by utilizing the parameters and imaging features of Sonazoid-contrast-enhanced ultrasound(CEUS).METHODS A retrospective analysis was conducted on the CEUS data of 239 lesions through case-control study.These patients received Sonazoid-CEUS within one week before surgery and were confirmed as HCC by postoperative pathology.Within the cases,patients were further categorized into well-differentiated and poorlydifferentiated group.Time-intensity curves of the region of interest in both arterial and Kupffer phases were generated,allowing for the acquisition of quantitative parameters to assess the diagnostic efficacy in distinguishing lesions between these two groups and determining an appropriate cut-off value.RESULTS Univariate analysis showed that the absolute value of enhancement intensity(EIAV),intensity ratio(IR)and intensity difference(ID)in Kupffer phase were statistically different between the groups with different degree(P=0.015,P=0.000,P=0.000).The sensitivity and specificity were 40.2%,82.4%,80.4% and 78.1%,86.9% and 74.5%,respectively,for differentiating HCC lesions with EIAV≥56.384 dB,IR≥1.215 and ID≥9.184 dB.The area under the receiver operating characteristic curve were 0.590,0.877,0.815.There was no significant difference in the parameters of arterial phase,including peak time,initial growth time,rise time and the absolute value of peak intensity of lesions between the two groups(P>0.05).Multivariate analysis showed that the level of alphafetoprotein(AFP)and IR were risk factors for poor differentiation(P=0.001).CONCLUSION Among the parameters of Sonazoid-CEUS,IR in Kupffer phase exhibits superior diagnostic efficacy with high sensitivity and specificity in the diagnose of pathological differentiation of HCC.Combined with preoperative AFP level,a more accurate diagnosis will be obtained.Compared with portal vein phase,Kupffer phase showed the ability to identify HCC lesions more sensitive.These findings hold significant guiding implications and reference value for clinical practice. 展开更多
关键词 Contrast-enhanced ultrasound Hepatocellular carcinoma Quantitative parameters Kupffer phase Pathological differentiation
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Adipose-derived mesenchymal stem cells from solid tissue and lipoaspirates:A comparative study of phenotype,growth,and secretome
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作者 Phuong Thi Minh Dam Dai Dang Nguyen +7 位作者 Anh Thi Thu Ngo Anh Minh Tran Truc Thanh Nguyen Phong Van Nguyen Chi Quynh Nguyen Anh Thi Tuyet Nguyen Quynh-Trang Thi Pham Uyen Thi Trang Than 《World Journal of Stem Cells》 2026年第1期36-48,共13页
BACKGROUND Mesenchymal stem cells(MSCs)are considered a promising therapy for various diseases due to their strong potential in regenerative medicine and immunomodulation.The tissue source of MSCs has gained attention... BACKGROUND Mesenchymal stem cells(MSCs)are considered a promising therapy for various diseases due to their strong potential in regenerative medicine and immunomodulation.The tissue source of MSCs has gained attention for its role in influencing their function,accessibility,and readiness for clinical use.AIM To identify the most suitable adipose source for MSC isolation and expansion for further applications.METHODS We isolated MSCs from solid adipose tissue and liposuction aspirates using the enzyme method.The MSCs were examined for their expansion using population doubling time,differentiation capacity using multilineage differentiation induction,surface markers using flow cytometry,and stability of chromosomes using the karyotyping method.Growth factors and cytokines in MSC-conditioned media were analyzed using the Luminex assay.RESULTS MSCs were isolated from solid adipose tissue and lipoaspirates and expanded from passage 0 to passage 2.All adipose-derived MSCs(AD-MSCs)exhibited the typical elongated,spindle-shaped morphology and comparable proliferation rate.They expressed positive surface markers(cluster of differentiation 73[CD73]:>97%,CD90:>98%,and CD105:>95%),and negative markers(<1%).All MSCs expressed similar levels of stemness genes(octamer-binding transcription factor 4,SRY-box 2,Krüppel-like factor,and MYC),colonyforming,and trilineage differentiation potential.Karyotyping analysis revealed normal chromosomal patterns in all samples,except one sample exhibiting a polymorphism(1qh+).Furthermore,the growth factors and cytokines of hepatocyte growth factor,vascular endothelial growth factor A,interleukin 6(IL-6),and IL-8 were detected in all AD-MSC conditioned media;but fibroblast growth factor-2 and keratinocyte growth factor were selectively expressed in conditioned media from solid or lipoaspirate AD-MSCs,respectively.CONCLUSION These findings indicate that AD-MSCs from both adipose sources possess all of the characteristic features of MSCs with source-specific secretome differences,which are suitable for further expansion and various clinical applications. 展开更多
关键词 Adipose-derived mesenchymal stem cells Adipose tissues Liposuction aspirates Multilineage differentiation Colony-forming units
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Cedrol ameliorates ulcerative colitis via myeloid differentiation factor 2-mediated inflammation suppression,with barrier restoration and microbiota modulation
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作者 Yi-Qing Zhao Yu Zhang +2 位作者 Yan Qin Rui-Ya Zhang Jun-Ping Wang 《World Journal of Gastroenterology》 2026年第2期135-151,共17页
BACKGROUND Ulcerative colitis(UC)is a chronic and treatment-resistant disorder requiring potent therapeutics that are effective and safe.Cedrol(CE)is a bioactive natural product present in many traditional Chinese med... BACKGROUND Ulcerative colitis(UC)is a chronic and treatment-resistant disorder requiring potent therapeutics that are effective and safe.Cedrol(CE)is a bioactive natural product present in many traditional Chinese medicines.It is known for its suppression of inflammation and mitigation of oxidative stress.Its therapeutic efficacy and mechanistic underpinnings in UC remain uncharacterized.AIM To investigate the therapeutic potential and mechanisms of CE in UC.METHODS The anti-inflammatory activity and intestinal barrier-repairing effects of CE were assessed in a dextran sulfate sodium-induced murine colitis model.Network pharmacology was employed to predict potential targets and pathways.Then molecular docking and dynamics simulations were utilized to confirm a stable interaction between CE and the toll-like receptor 4(TLR4)/myeloid differentiation factor 2(MD2)complex.The anti-inflammatory mechanisms were further verified using in vitro assays.Additionally,the gut microbiota composition was analyzed via 16S rRNA gene sequencing.RESULTS CE significantly alleviated colitis symptoms,mitigated histopathological damage,and suppressed inflammation.Moreover,CE restored intestinal barrier integrity by enhancing mucus secretion and upregulating tight junction proteins(zonula occludens 1,occludin,claudin-1).Mechanistically,CE stably bound to MD2,inhibiting lipopolysaccharide-induced TLR4 signaling in RAW264.7 cells.This led to suppression of the downstream mitogen-activated protein kinase and nuclear factor kappa B signaling pathways,downregulating the expression of tumor necrosis factor-alpha,interleukin-1β,and interleukin-6.Gut microbiota analysis revealed that CE reversed dextran sulfate sodium-induced dysbiosis with significant enrichment of butyrogenic Christensenella minuta.CONCLUSION CE acted on MD2 to suppress proinflammatory cascades,promoting mucosal barrier reconstitution and microbiota remodeling and supporting its therapeutic use in UC. 展开更多
关键词 CEDROL Ulcerative colitis Toll-like receptor 4 Myeloid differentiation factor 2 Signaling pathways Gut microbiota
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Mesenchymal stem cell-derived small extracellular vesicles enhance the therapeutic effect of retinal progenitor cells in retinal degenerative disease rats
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作者 Chunge Ren Min Chen +10 位作者 Bangqi Ren Yuxiao Zeng Qiang Tan Qiyou Li Xue Zhang Yajie Fang Yixiao Zhou Weitao Zhang Fang Chen Baishijiao Bian Yong Liu 《Neural Regeneration Research》 2026年第2期821-832,共12页
Our previous study demonstrated that combined transplantation of bone marrow mesenchymal stem cells and retinal progenitor cells in rats has therapeutic effects on retinal degeneration that are superior to transplanta... Our previous study demonstrated that combined transplantation of bone marrow mesenchymal stem cells and retinal progenitor cells in rats has therapeutic effects on retinal degeneration that are superior to transplantation of retinal progenitor cells alone.Bone marrow mesenchymal stem cells regulate and interact with various cells in the retinal microenvironment by secreting neurotrophic factors and extracellular vesicles.Small extracellular vesicles derived from bone marrow mesenchymal stem cells,which offer low immunogenicity,minimal tumorigenic risk,and ease of transportation,have been utilized in the treatment of various neurological diseases.These vesicles exhibit various activities,including anti-inflammatory actions,promotion of tissue repair,and immune regulation.Therefore,novel strategies using human retinal progenitor cells combined with bone marrow mesenchymal stem cell-derived small extracellular vesicles may represent an innovation in stem cell therapy for retinal degeneration.In this study,we developed such an approach utilizing retinal progenitor cells combined with bone marrow mesenchymal stem cell-derived small extracellular vesicles to treat retinal degeneration in Royal College of Surgeons rats,a genetic model of retinal degeneration.Our findings revealed that the combination of bone marrow mesenchymal stem cell-derived small extracellular vesicles and retinal progenitor cells significantly improved visual function in these rats.The addition of bone marrow mesenchymal stem cell-derived small extracellular vesicles as adjuvants to stem cell transplantation with retinal progenitor cells enhanced the survival,migration,and differentiation of the exogenous retinal progenitor cells.Concurrently,these small extracellular vesicles inhibited the activation of regional microglia,promoted the migration of transplanted retinal progenitor cells to the inner nuclear layer of the retina,and facilitated their differentiation into photoreceptors and bipolar cells.These findings suggest that bone marrow mesenchymal stem cell-derived small extracellular vesicles potentiate the therapeutic efficacy of retinal progenitor cells in retinal degeneration by promoting their survival and differentiation. 展开更多
关键词 DIFFERENTIATION inflammation mesenchymal stem cells MICROGLIA migration rat retinal degeneration retinal progenitor cells small extracellular vesicles stem cell transplantation
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Empowering the NSC-34 cell line as a motor neuron model: Cytosine arabinoside's action
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作者 Giuseppe Vitale Susanna Amadio +1 位作者 Francesco Liguori Cinzia Volonté 《Neural Regeneration Research》 2026年第1期357-364,共8页
The NSC-34 cell line is a widely recognized motor neuron model and various neuronal differentiation protocols have been exploited. Under previously reported experimental conditions, only part of the cells resemble dif... The NSC-34 cell line is a widely recognized motor neuron model and various neuronal differentiation protocols have been exploited. Under previously reported experimental conditions, only part of the cells resemble differentiated neurons;however, they do not exhibit extensive and time-prolonged neuritogenesis, and maintain their duplication capacity in culture. The aim of the present work was to facilitate long-term and more homogeneous neuronal differentiation in motor neuron–like NSC-34 cells. We found that the antimitotic drug cytosine arabinoside promoted robust and persistent neuronal differentiation in the entire cell population. Long and interconnecting neuronal processes with abundant growth cones were homogeneously induced and were durable for up to at least 6 weeks in culture. Moreover, cytosine arabinoside was permissive, dispensable, and mostly irreversible in priming NSC-34 cells for neurite initiation and regeneration after mechanical dislodgement. Finally, the expression of the cell proliferation antigen Ki67 was inhibited by cytosine arabinoside, whereas the expression levels of neuronal growth associated protein 43, vimentin, and motor neuron–specific p75, Islet2, homeobox 9 markers were upregulated, as confirmed by western blot and/or confocal immunofluorescence analysis. Overall, these findings support the use of NSC-34 cells as a motor neuron model for properly investigating neurodegenerative mechanisms and prospectively identifying neuroprotective strategies. 展开更多
关键词 cytosine arabinoside Islet2 Hb9 Ki67 mitosis inhibition neurite initiation neurite regeneration neuronal differentiation protocol NSC-34 P75
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床旁心肺五项联检对急性胸痛鉴别诊断价值的研究
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作者 徐美丽 肖欢 +1 位作者 韦雅婷 杨芝富 《中国现代药物应用》 2026年第4期72-76,共5页
目的 探讨床旁心肺五项联检对急性胸痛鉴别诊断的价值。方法 回顾性分析6870例急性胸痛患者的病历资料,根据患者严重程度不同分为致命组(n=452)和非致命组(n=6418),再根据不同胸痛疾病将致命组患者分为急性心肌梗死患者(n=284)、急性主... 目的 探讨床旁心肺五项联检对急性胸痛鉴别诊断的价值。方法 回顾性分析6870例急性胸痛患者的病历资料,根据患者严重程度不同分为致命组(n=452)和非致命组(n=6418),再根据不同胸痛疾病将致命组患者分为急性心肌梗死患者(n=284)、急性主动脉夹层患者(n=110)、急性肺动脉栓塞患者(n=58)。比较两组床旁心肺五项联检指标[肌钙蛋白I(cTnI)、肌酸激酶同工酶(CK-MB)、肌红蛋白(Myo)、D-二聚体(D-D)和脑钠肽(BNP)]水平、三种不同致命性胸痛疾病患者床旁心肺五项联检指标水平,根据接受者操作特性曲线(ROC)评价床旁心肺五项联检指标在鉴别三种不同致命性胸痛疾病中的诊断价值。结果 致命组BNP、D-D、Myo、cTnI、CK-MB水平分别为(202.51±8.65)ng/L、(2053.35±23.14)μg/L、(323.10±17.91)μg/L、(10.17±0.81)μg/L、(5.36±0.75)μg/L,明显高于非致命组的(68.48±7.34)ng/L、(1023.78±21.05)μg/L、(224.38±16.23)μg/L、(3.98±0.76)μg/L、(3.09±0.63)μg/L,差异显著(P<0.05)。急性心肌梗死、急性主动脉夹层、急性肺栓塞患者BNP、D-D、Myo、cTnI、CK-MB水平比较,差异显著(P<0.05)。急性心肌梗死患者BNP、Myo、cTnI、CK-MB水平明显高于急性主动脉夹层患者、急性肺栓塞患者,急性肺栓塞患者D-D水平高于急性主动脉夹层患者、急性心肌梗死患者, Myo水平高于急性主动脉夹层患者,急性主动脉夹层患者BNP、cTnI、CK-MB水平高于急性肺栓塞患者,差异显著(P<0.05)。BNP、D-D、Myo、cTnI、CK-MB单独检测及联合检测诊断致命性胸痛患者中急性心肌梗死、急性肺栓塞和急性主动脉夹层等疾病的曲线下面积(AUC)均>0.70,有一定预测价值。结论 床旁心肺五项联检对鉴别急性胸痛患者有重要意义,值得推广使用。 展开更多
关键词 床旁心肺五项联检 急性胸痛 主动脉夹层 肺栓塞 心肌梗死 鉴别诊断
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基质金属蛋白酶9介导线粒体自噬调控成骨及成肌
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作者 王思微 姚啸生 +3 位作者 戚晓楠 王禹 崔海舰 赵佳萱 《中国组织工程研究》 北大核心 2026年第18期4557-4567,共11页
背景:基质金属蛋白酶9可以影响成骨和成肌分化,但是其具体调控机制不甚清楚。目的:探讨氧化应激损伤对小鼠MC3T3-E1细胞和C2C12细胞线粒体自噬的影响,进一步研究基质金属蛋白酶9作为关键分子通过介导PTEN诱导激酶1/Parkin信号通路调控... 背景:基质金属蛋白酶9可以影响成骨和成肌分化,但是其具体调控机制不甚清楚。目的:探讨氧化应激损伤对小鼠MC3T3-E1细胞和C2C12细胞线粒体自噬的影响,进一步研究基质金属蛋白酶9作为关键分子通过介导PTEN诱导激酶1/Parkin信号通路调控线粒体自噬并影响成骨、成肌分化的作用。方法:选取小鼠C2C12细胞和MC3T3-E1细胞进行分化与培养,分别设置对照组、模型组(H2O2诱导氧化损伤)、GM6001(基质金属蛋白酶9抑制剂)组、3-甲基腺嘌呤(PTEN诱导激酶1/Parkin通路抑制剂)组,各组细胞处理时间均为24 h。应用流式细胞术检测细胞内线粒体膜电位、活性氧水平;透射电镜观察细胞线粒体损伤及自噬情况;Western blot检测基质金属蛋白酶9蛋白表达;qRT-PCR和Western blot检测P62、微管相关蛋白轻链3、PTEN诱导激酶1、Parkin的mRNA和蛋白表达;Western blot检测MC3T3-E1细胞中成骨蛋白骨钙素、骨桥蛋白、Runt相关转录因子2蛋白表达;qRT-PCR法检测C2C12细胞中成肌基因生肌因子5、生肌因子6、生肌决定因子1、肌细胞生成素mRNA表达。结果与结论:①在MC3T3-E1细胞和C2C12细胞中,与对照组相比,模型组、GM6001组、3-甲基腺嘌呤组线粒体膜电位均降低,活性氧水平均升高;与模型组相比,GM6001组活性氧水平降低;与GM6001组相比,3-甲基腺嘌呤组活性氧水平升高;②透射电镜观察模型组线粒体损伤较为严重,线粒体自噬形成;GM6001组线粒体损伤情况有所改善;3-甲基腺嘌呤组线粒体损伤情况较模型组减轻,自噬程度减弱;③与对照组相比,模型组、GM6001组、3-甲基腺嘌呤组基质金属蛋白酶9蛋白表达升高;与模型组相比,3-甲基腺嘌呤组基质金属蛋白酶9蛋白表达显著降低;与3-甲基腺嘌呤组相比,GM6001组基质金属蛋白酶9蛋白表达显著降低;④与对照组相比,模型组P62 mRNA及蛋白表达降低,GM6001组进一步降低,3-甲基腺嘌呤组升高;与对照组相比,模型组微管相关蛋白轻链3Ⅱ、微管相关蛋白轻链3Ⅰ、PTEN诱导激酶1、Parkin mRNA及蛋白表达升高,GM6001组进一步升高,3-甲基腺嘌呤组降低;⑤在MC3T3-E1细胞系中,与对照组相比,模型组、GM6001组、3-甲基腺嘌呤组骨钙素、骨桥蛋白、Runt相关转录因子2蛋白表达降低;与模型组相比,GM6001组骨钙素、骨桥蛋白表达升高;与GM6001组相比,3-甲基腺嘌呤组骨钙素、骨桥蛋白表达降低;⑥在C2C12细胞系中,与对照组相比,模型组、GM6001组、3-甲基腺嘌呤组生肌因子5、生肌因子6、生肌决定因子1、肌细胞生成素mRNA表达降低;与模型组相比,GM6001组上述成肌基因表达升高;与GM6001组相比,3-甲基腺嘌呤组上述成肌基因表达降低。结果表明,基质金属蛋白酶9在氧化损伤模型中高表达,其抑制剂可以增强氧化损伤环境下的线粒体自噬,这种调控是基于PTEN诱导激酶1/Parkin通路的激活,并对成骨、成肌分化具有促进作用。 展开更多
关键词 骨质疏松症 肌少症 肌少-骨质疏松症 基质金属蛋白酶9 线粒体自噬 PINK1/Parkin通路 成骨分化 成肌分化
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基于集成学习的IgA肾病中医辨证智能模型的构建及应用
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作者 吴倩 陈意 +2 位作者 余浩凯 周奇 邹川 《广州中医药大学学报》 2026年第1期246-256,共11页
【目的】基于机器学习方法构建IgA肾病的中医智能辨证模型。【方法】检索中国知网(CNKI)、万方数据知识服务平台(Wanfang)、维普中文科技期刊数据库(VIP)、中国生物医学文献服务系统(CBM)自建库至2024年9月1日收录的IgA肾病文献以及古... 【目的】基于机器学习方法构建IgA肾病的中医智能辨证模型。【方法】检索中国知网(CNKI)、万方数据知识服务平台(Wanfang)、维普中文科技期刊数据库(VIP)、中国生物医学文献服务系统(CBM)自建库至2024年9月1日收录的IgA肾病文献以及古今医案云平台中的IgA肾病医案数据。建立IgA肾病中医信息数据库,将数据样本按7∶3比例分为训练集和测试集。应用超参数调优后的支持向量机(SVM)、梯度提升机(GBM)、随机森林(RF)、多层感知器神经网络(MLP)等机器学习算法(基学习器)对数据集进行量化分析,建立IgA肾病辨证智能模型,然后通过集成算法对以上4种分类器模型进行融合,组成一个强学习器。采用五折交叉验证对模型的性能进行评价,评价指标包括准确率(accuracy)、精确率(precision)、召回率(recall)、F1值(F1-score)、受试者工作特征曲线下面积(AUC)值。【结果】以IgA肾病中医四诊信息为输入变量,共包括63项,即38个症状、13种舌象、12种脉象;以IgA肾病中医证型为输出变量,共包括外感风热证、肺脾气虚证、气阴两虚证、气阴两虚夹湿热证4种证型。各模型的拟合效果较好,准确率、精确率、召回率、F1值、AUC值均在0.83以上;其中集成学习模型的准确率、查准率与查全率最高,其准确率、AUC值、F1值、召回率、精确率分别为0.92、0.98、0.85、0.88、0.85,均高于其他算法模型。综合评价各指标结果表明以集成模型最优;集成学习模型参数的中医解释基本符合中医诊断原理。【结论】所构建的集成模型能够综合各分类器模型的优点,具有更好的稳定性,其性能和泛化能力均优于单一的基学习器;结果提示将人工智能应用于IgA肾病中医辨证智能模型的构建,在方法学方面是可行的。 展开更多
关键词 IGA肾病 中医辨证模型 医案 人工智能 机器学习 集成学习 方法学
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糖尿病与肥厚型心肌病的因果关系:GWAS数据库信息分析
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作者 赵迎新 郎彤 +1 位作者 孟令丙 高玉霞 《中国组织工程研究》 北大核心 2026年第11期2933-2948,共16页
背景:糖尿病与肥厚型心肌病相互影响,糖尿病患者心血管并发症风险显著升高,但两者之间的因果关系及分子机制尚不明确。目的:利用孟德尔随机化方法,结合GWAS和GEO数据库数据,评估糖尿病对肥厚型心肌病的因果效应,通过生物信息学分析筛选... 背景:糖尿病与肥厚型心肌病相互影响,糖尿病患者心血管并发症风险显著升高,但两者之间的因果关系及分子机制尚不明确。目的:利用孟德尔随机化方法,结合GWAS和GEO数据库数据,评估糖尿病对肥厚型心肌病的因果效应,通过生物信息学分析筛选关键调控因子。方法:从最新的全基因组关联研究(GWAS,由美国国家人类基因组研究所和欧洲生物信息研究所合作建立)数据库中获取162个与糖尿病相关的单核苷酸多态性,这些数据来自24659例糖尿病患者和459939名对照参与者,获取肥厚型心肌病数据,包括507例肥厚型心肌病病例和489220名对照参与者,进行两样本孟德尔随机化分析,使用逆方差加权法评估糖尿病与肥厚型心肌病之间的因果关系。下载基因表达数据库(GEO)中的糖尿病数据集GSE184050和肥厚型心肌病数据集GSE160997,利用WGCNA探讨与糖尿病和肥厚型心肌病相关的重要模块及核心基因。通过GSEA探讨核心基因相关的富集术语和通路。将核心基因输入比较毒理学基因组数据库(CTD)网站以确定与核心基因相关的疾病。采用多种算法探讨HSF1在糖尿病和肥厚型心肌病中的作用。结果与结论:①以糖尿病为暴露因子,提取了160个单核苷酸多态性的分析结果,采用逆方差加权、MR-Egger和加权中位数回归方法评估遗传预测的糖尿病与肥厚型心肌病之间的因果关系,MR-Egger检验显示糖尿病与肥厚型心肌病之间存在显著因果关联,确定HSF1为糖尿病与肥厚型心肌病因果关系的核心生物标志物(P=0.01802898),加权中位数和逆方差加权法也提供了一致趋势。通过GEO数据库的数据验证确认了HSF1是同时影响糖尿病和肥厚型心肌病的潜在核心生物标志物。HSF1在糖尿病中高表达、在肥厚型心肌病中低表达。通过逐一移除单核苷酸多态性并重复孟德尔随机化分析的敏感性分析显示,没有单一单核苷酸多态性显著影响因果关系估计。将HSF1输入CTD网站以识别与核心基因相关的疾病,结果显示HSF1与糖尿病、2型糖尿病、肥厚型心肌病、心脏病、高血压、代谢紊乱和炎症等相关联。②研究主要基于国际大型数据库(如欧洲人群的GWAS和GEO表达谱数据),采用遗传工具变量进行因果推断,具有较强的科学性。中国生物医学研究应加强本土多组学数据的积累和整合,借助类似方法探索适用于中国人群的精准预防和治疗靶点。 展开更多
关键词 糖尿病 肥厚型心肌病 孟德尔随机化 HSF1 遗传学 差异表达基因
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冈底斯带曲水岩基新生代热演化历史:来自(U-Th)/He热年代学的约束
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作者 高庆泽 孟元库 +3 位作者 裴军令 孙敬博 熊发挥 赵雨生 《岩石学报》 北大核心 2026年第1期123-138,共16页
青藏高原的隆升过程一直是学术界长期关注的前沿科学问题,对理解大陆动力学演化与环境变化具有重要意义。位于拉萨地体南缘的冈底斯岩基是研究青藏高原构造隆升最为理想的区域。本文以冈底斯带曲水岩基及火山沉积地层为研究对象,系统采... 青藏高原的隆升过程一直是学术界长期关注的前沿科学问题,对理解大陆动力学演化与环境变化具有重要意义。位于拉萨地体南缘的冈底斯岩基是研究青藏高原构造隆升最为理想的区域。本文以冈底斯带曲水岩基及火山沉积地层为研究对象,系统采集了7个具有代表性的岩石样品,包括闪长岩、花岗岩、砂岩及安山岩等类型,通过结合磷灰石和锆石(U-Th)/He热年代学分析,对曲水岩基新生代的热演化历史进行了详细的约束。7个磷灰石样品的(U-Th)/He年龄加权平均值范围为6.9±1.6Ma~13.98±0.82Ma,其中邻近雅鲁藏布江的样品年龄明显年轻(6.9±1.6Ma),推测与河流侵蚀作用有关,其余样品年龄主要集中于中新世中期(~13Ma)。4个锆石样品的(U-Th)/He年龄加权平均值范围为17.0±1.6Ma~39.4±9.2Ma,仅最北部样品显示始新世年龄(39.4±9.2Ma),其余样品年龄均为中新世(~17Ma)。热历史模拟揭示冈底斯曲水岩基在新生代经历了两期显著的快速冷却过程:(1)始新世中期-渐新世早期(43~30Ma),可能与藏南拉萨的地壳增厚有关;(2)中新世早期-中期(21~10Ma),可能归因于拉萨岩石圈拆沉及软流圈上涌等深部动力学过程。此外,结合冈底斯岩基已有的低温热年代学数据,综合分析认为,冈底斯岩基新生代差异折返与区域构造活动、深部动力学过程和河流侵蚀等多重机制的协同作用密切相关。这些共同作用为理解青藏高原南缘的构造-地貌联系和隆升过程提供了新的制约和见解。 展开更多
关键词 曲水岩基 构造演化 (U-Th)/He 新生代 差异折返
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