Many important problems in science and engineering require solving the so-called parametric partial differential equations(PDEs),i.e.,PDEs with different physical parameters,boundary conditions,shapes of computational...Many important problems in science and engineering require solving the so-called parametric partial differential equations(PDEs),i.e.,PDEs with different physical parameters,boundary conditions,shapes of computational domains,etc.Typical reduced order modeling techniques accelerate the solution of the parametric PDEs by projecting them onto a linear trial manifold constructed in the ofline stage.These methods often need a predefined mesh as well as a series of precomputed solution snapshots,and may struggle to balance between the efficiency and accuracy due to the limitation of the linear ansatz.Utilizing the nonlinear representation of neural networks(NNs),we propose the Meta-Auto-Decoder(MAD)to construct a nonlinear trial manifold,whose best possible performance is measured theoretically by the decoder width.Based on the meta-learning concept,the trial manifold can be learned in a mesh-free and unsupervised way during the pre-training stage.Fast adaptation to new(possibly heterogeneous)PDE parameters is enabled by searching on this trial manifold,and optionally fine-tuning the trial manifold at the same time.Extensive numerical experiments show that the MAD method exhibits a faster convergence speed without losing the accuracy than other deep learning-based methods.展开更多
[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experimen...[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experiments were designed to optimize the extraction process of total flavonoids from P.chinense Pursh with the volume fraction of ethanol,the ratio of material to liquid,heating reflux extraction time and extraction times as factors,and the content of total flavonoids as the index.A verification test was carried out.The optimized extraction process was adopted to compare the contents of total flavonoids from different parts of P.chinense Pursh.[Results]The best extraction process was extracting the powder of P.chinense Pursh for 2.0 h with 20 times of 55%ethanol by reflux twice.Under this condition,the contents of total flavonoids were 3.63%,8.90%,11.28%,and 4.36%from stems,leaves,flowers and whole grass of P.chinense Pursh,respectively.[Conclusions]The process is reasonable,feasible and stable,and can effectively extract total flavonoids from P.chinense Pursh.The contents of total flavonoids from different parts of P.chinense Pursh were quite different,and the value was higher in the leaves and flowers,so the proportions of leaves and flowers should be paid attention to in the industrial processing of P.chinense Pursh.展开更多
Rationale:Aortic dissection is a life-threatening medical emergency associated with high morbidity and mortality.Preoperative mesenteric malperfusion increases the surgical risk and mortality in patients with type B a...Rationale:Aortic dissection is a life-threatening medical emergency associated with high morbidity and mortality.Preoperative mesenteric malperfusion increases the surgical risk and mortality in patients with type B aortic dissection.For DeBakey type III B patients involving most of the thoracoabdominal aorta,endovascular treatment to improve true lumen perfusion may have limited benefits.Organ reperfusion on-time is crucial.Patient concerns:A 38-year-old man was admitted with sudden severe upper abdominal pain.Emergency CTA of the entire aorta revealed an aortic dissection with an entry tear in the descending aortic arch involving the celiac trunk,superior mesenteric artery,bilateral common iliac arteries and right external iliac artery,with thrombosis in the superior mesenteric artery.Diagnoses:The patient was diagnosed with DeBakey type III aortic dissection with mesenteric artery embolism.Enhanced chest CT showed the entry tear location and involvement of major arteries.Angiography confirmed partial blood flow in the superior mesenteric artery.Interventions:The patient underwent endovascular aortic stent-graft implantation through the left femoral artery,covering the descending aortic arch and sealing the entry tear.Postoperatively,the patient received intensive care,including ventilatory support,CRRT,anti-infection therapy,vasoactive drugs and lumbar cistern drainage.Outcomes:Two weeks postoperatively,the patient developed massive black stools,indicative of intestinal obstruction and necrosis.Exploratory laparotomy revealed ischemic necrosis and rupture of the stomach,small intestine,and colon.Despite surgical efforts,the patient’s condition deteriorated,leading to death from severe infection,acid-base imbalance and multiple organ failure.展开更多
Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface ...Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface structure of Fe_(3)O_(4)at atomic scale.Here,using a combination of first-principles calculations,particle swarm optimization(PSO)method and machine learning,we investigate the possible reconstruction and stability of Fe_(3)O_(4)(001)surface.The results show that besides the subsurface cation vacancy(SCV)reconstruction,an A layer with Fe vacancy(A-layer-V_(Fe))reconstruction of the(001)surface also shows very low surface energy especially at oxygen poor condition.Molecular dynamics simulation based on the iron–oxygen interaction potential function fitted by machine learning further confirms the thermodynamic stability of the A-layer-V_(Fe)reconstruction.Our results are also instructive for the study of surface reconstruction of other metal oxides.展开更多
Piezoelectric energy harvesting is considered as an ideal power resource for low-power consumption gadgets in vibrational environments.The energy extraction efficiency depends highly on the interface circuit,and shoul...Piezoelectric energy harvesting is considered as an ideal power resource for low-power consumption gadgets in vibrational environments.The energy extraction efficiency depends highly on the interface circuit,and should be highly improved to meet the power requirements.The nonlinear interface circuits in discrete components have been extensively explored and developed with the advantages of easy implementation,stable operation,high efficiency,and low cost.This paper reviews the state-of-the-art progress of nonlinear piezoelectric energy harvesting interface circuits in discrete components.First,the working principles and the advantages/disadvantages of four classical interface circuits are described.Then,the improved circuits based on the four typical circuits and other types of circuits are introduced in detail,and the advantages/disadvantages,output power,efficiency,energy consumption,and practicability of these circuits are analyzed.Finally,the future development trends of nonlinear piezoelectric energy harvesting circuits,e.g.,self-powered extraction,low-power consumption,and broadband characteristic,are predicted.展开更多
Glioma is one of the lethal central nervous system tumors.The infiltrative and invasive growth nature makes it difficult to identify the boundary between glioma and the normal tissues,resulting in inevitable recurrenc...Glioma is one of the lethal central nervous system tumors.The infiltrative and invasive growth nature makes it difficult to identify the boundary between glioma and the normal tissues,resulting in inevitable recurrence after surgery operation.Gliomas do not metastasize,so to prevent the residual tumor from proliferating or invading is a key challenge.Previous report indicated that hypotaurine could facilitate glioma invasion and suppress demethylases’activities.Using a hypotaurine synthesis deficient U251 cell line,we proved that the cells invasion ability was impaired.Gene expression profile analysis exhibited that knocking down one of the key enzymes of hypotaurine synthesis,2-aminoethanethiol dioxygenase(ADO),significantly affected the extracellular matrix-receptor process.Of that process,Wnt5a expression was severely upregulated by decreased intracellular ADO expression.Cells cultured at the presence of hypotaurine showed a decrease in intracellular Wnt5a protein and mRNA levels.This phenotype was due to hypermethylation of Wnt5a promoter,which was most likely the result of hypotaurine’s inhibiting demethylases activities.Collectively,this study demonstrated that hypotaurine synthesis deficient U251 cells were prone to epigenetic modification and Wnt5a seemed to be a tumor suppressor under that circumstance.This tumor suppression effect is warranted to be reevaluated in real tumor samples and the relevant evidence might contribute to develop new glioma interference strategies.展开更多
Influenza-associated encephalopathy (IAE) can perform as varying patterns of neuroimaging. Central brain herniation (CBH) secondary to IAE is rare;it may be a bad prognosis. Here, we presented a 4-year-old girl with i...Influenza-associated encephalopathy (IAE) can perform as varying patterns of neuroimaging. Central brain herniation (CBH) secondary to IAE is rare;it may be a bad prognosis. Here, we presented a 4-year-old girl with influenza who had a pontocerebellar hypoplasia (PCH) history;she performed the second Magnetic Resonance Imaging (MRI) on Day 6 from onset, showed the diffuse edema and the occurrence of central herniation;the medulla was “Z-like” folded and the basal cisterns were obliterated completely. Finally she was declared dead. The imbalance between supratentorial and infratentorial pressure can lead to the occurrence of CBH. Severe edema relates to IAE and unstable structure of the posterior fossa might be the main reason for the herniation. MRI is helpful in early diagnosis. Early treatment of cerebral edema in patients with congenital abnormalities of the posterior fossa is vital for their management.展开更多
The swine flu, H1N1 virus was outbroken in Mexico and the United States in April 2009 and then rapidly spread worldwide. The World Health Organization declared that the outbreak of influenza is caused by a new subtype...The swine flu, H1N1 virus was outbroken in Mexico and the United States in April 2009 and then rapidly spread worldwide. The World Health Organization declared that the outbreak of influenza is caused by a new subtype of influenza H1N1 influenza virus. And researchers have isolated some oseltamivir resistance strains in 2009 swine flu which makes the imminency of research and development of new anti influenza drug. The CPSF30 binding pocket of effector domain in NS1 protein is very important in the replication of influanza A virus and is a new attractive anti flu drug target. But up to now there is no antiviral drug target this pocket. Here we employ molecular docking to screening of about 200,000 compounds. We find four novel compounds with high binding energy. Binding comformation analysis revealed that these small molecules can interact with the binding pocket by some strong hydrophobic interaction. This study find some novel small molecules can be used as lead compounds in the development of new antiinfluenza drug based on CPSF30 pocket.展开更多
OBJECTIVE To study the relationship between bFGF gene expression and proliferative activity in meningiomas. METHODS Thirty-seven samples of meningioma were examed using Northern hybridization for bFGF-gene expression ...OBJECTIVE To study the relationship between bFGF gene expression and proliferative activity in meningiomas. METHODS Thirty-seven samples of meningioma were examed using Northern hybridization for bFGF-gene expression and immunohistochemi- stry for bFGF protein expression and the Ki-67LI. RESULTS bFGF mRNA was detected in 22 meningiomas of Grade Ⅰ and in all samples of Grade Ⅱ and Ⅲ. Six of the Grade Ⅰ tumors were negative, giving an overall positive rate of 83.8 % for bFGF mRNA. Autoradiography was conducted using a thin scaning apparatus, bFGF mRNA expression compared to that for β-actin was 0.34±0.06 for Grade Ⅰ tumors compared to 0.82±0.12 for Grade Ⅱ and Ⅲ tumors. The difference was highly significant (P〈0.001). The results of immunohistochemistry showed that the number of the positive cells for the bFGF protein was 29.7±7.6% in Grade Ⅰ tumors and 63.2±11.7 % in Grade Ⅱ plus Ⅲ, resulting in a significant difference between them (P〈0.001) . The Ki-67LI was found to be 2.8±1.1% in Grade Ⅰ and 6.5±1.3 % in Grade Ⅱ plus Ⅲ. The former was significantly lower than the later (P〈0.001). CONCLUSION The expression of bFGF was correlated well with the malignancy of the meningiomas.展开更多
Garcinia Glycosides is a candidate drug obtained by structural modification of Gambogic Acid (GA), which was acquired through High Throughput Screening(HTS). As Garcinia Glycosides is an effective but insoluble anti-t...Garcinia Glycosides is a candidate drug obtained by structural modification of Gambogic Acid (GA), which was acquired through High Throughput Screening(HTS). As Garcinia Glycosides is an effective but insoluble anti-tumor drug, the aim of this study was to obtain a solid dispersion form Garcinia Glycosides by using solvent-melt method so that improve the solubility and dissolution rate. The solid dispersion was characterized by High Performance Liquid Chromatography (HPLC), infrared spectroscopy and evaluated the intestinal absorption of the drug by rat in situ single pass intestinal perfusion. The results showed the increase of solubility, dissolution velocity and absorption compared to other forms. This indicated that solid dispersion could greatly improve the relative bioavailability of Garcinia Glycosides in vivo.展开更多
Graphene-h-BN hybrid nanostructures are grown in one step on the Pt(111) surface by ultra-high vacuum chemical vapor deposition using a single precursor,the dimethylamino borane complex.By varying the deposition condi...Graphene-h-BN hybrid nanostructures are grown in one step on the Pt(111) surface by ultra-high vacuum chemical vapor deposition using a single precursor,the dimethylamino borane complex.By varying the deposition conditions,different nanostructures ranging from a fully continuous hybrid monolayer to well-separated Janus nanodots can be obtained.The growth starts with heterogeneous nucleation on morphological defects such as Pt step edges and proceeds by the addition of small clusters formed by the decomposition of the dimethylamino borane complex.Scanning tunneling microscopy measurements indicate that a sharp zigzag in-plane boundary is formed when graphene grows aligned with the Pt substrate and consequently with the h-BN layer as well.When graphene is rotated by 30°,the graphene armchair edges are seamlessly connected to h-BN zigzag edges.This is confirmed by a thorough density functional theory (DFT) study.Angle resolved photoemission spectroscopy (ARPES) data suggests that both h-BN and graphene present the typical electronic structure of self-standing non-interacting materials.展开更多
Epidermal growth factor receptor (EGFR) mediates multiple signaling pathways that regulate cell migration, proliferation, and differentiation. Adaptor pro- tein APPL1 has been reported to function as a downstream ef...Epidermal growth factor receptor (EGFR) mediates multiple signaling pathways that regulate cell migration, proliferation, and differentiation. Adaptor pro- tein APPL1 has been reported to function as a downstream effector of EGFR signaling pathway. However, molecular mechanisms underlying the role of APPL1 downstream of EGFR signaling remains elusive. Here, we identified APPL1 as a critical molecule that interacts with EGFR. Suppression of APPL 1 by siRNA inhibited EGF-stimulated Akt phosphorylation. Functionally, EGF stimulation of cells caused phosphorylation of APPL1 at Ser636, which subsequently promoted the interaction between APPL1 and EGFR, indicating that APPL1 sensitizes EGF stimulation by acting at a site downstream of the EGFR signaling. Importantly, non-phosphorylatable mutant of APPL1 reduced cell migration compared with wild-type APPL1 in an Akt-dependent manner. Our study reveals a novel function of APPL1 in EGF signaling and defines a novel molecular mechanism by which phosphorylation of APPL1 upon EGF stimulation regulates cell migration underlying EGF-stimulated Akt pathway.展开更多
Total paeony glycoside(TPG) is obtained from Radix Paeoniae Rubra with a variety of bioactivities. However, the low solubility and bioavailability limit its application. The present study aimed to develop TPG nanocr...Total paeony glycoside(TPG) is obtained from Radix Paeoniae Rubra with a variety of bioactivities. However, the low solubility and bioavailability limit its application. The present study aimed to develop TPG nanocrystals to increase the dissolution and then improve the oral bioavailability. TPG nanocrystals were prepared via precipitation and high-pressure homogenization method. The physical-chemical properties of the optimal TPG nanocrystals in terms of particle size, zeta potential, morphology and crystallinity were evaluated. The results showed that TPG nanocrystals had a mean particle size of(210.2±2.5) nm, a polydispersity index of 0.191±0.033 and a zeta potential of(–22.4±1.2) mV. The result of differential scanning calorimetry showed that the nanocrystals were still in crystalline state after the preparation procedure. Transmission electron microscopy(TEM) results showed that the nanosuspension was in spherical shape. The pharmacokinetics of TPG nanocrystals for rats was investigated by liquid chromatography-tandem mass spectroscopy(LC-MS/MS). Compared with the TPG coarse suspension, TPG nanocrystals exhibited significant increase in AUC0–∞(approximately 1.85-fold). Taken together, TPG nanocrystals could be used as a promising drug delivery system due to the enhanced oral bioavailability of TPG.展开更多
基金supported by the National Key R&D Program of China under Grant No.2021ZD0110400.
文摘Many important problems in science and engineering require solving the so-called parametric partial differential equations(PDEs),i.e.,PDEs with different physical parameters,boundary conditions,shapes of computational domains,etc.Typical reduced order modeling techniques accelerate the solution of the parametric PDEs by projecting them onto a linear trial manifold constructed in the ofline stage.These methods often need a predefined mesh as well as a series of precomputed solution snapshots,and may struggle to balance between the efficiency and accuracy due to the limitation of the linear ansatz.Utilizing the nonlinear representation of neural networks(NNs),we propose the Meta-Auto-Decoder(MAD)to construct a nonlinear trial manifold,whose best possible performance is measured theoretically by the decoder width.Based on the meta-learning concept,the trial manifold can be learned in a mesh-free and unsupervised way during the pre-training stage.Fast adaptation to new(possibly heterogeneous)PDE parameters is enabled by searching on this trial manifold,and optionally fine-tuning the trial manifold at the same time.Extensive numerical experiments show that the MAD method exhibits a faster convergence speed without losing the accuracy than other deep learning-based methods.
基金Supported by Key Research and Development Program of Sichuan Province(2022YFS0436)Natural Science Foundation of Sichuan Province(2022NSFSC1738)+4 种基金Science and Technology Planning Project of Luzhou City(2021-JYJ-109,2023SYF120)Special Project of Traditional Chinese Medicine Scientific Research of Sichuan Provincial Administration of Traditional Chinese Medicine(2020CP0029)Southwest Medical University-Luzhou Hospital of Traditional Chinese Medicine Base Project(2019-LH003)Open Subject of Luzhou Key Laboratory of Fine Chemical Application Technology(HYJY-2106-B)Southwest Medical University Undergraduate Student Innovation and Entrepreneurship Training Program(202310632074).
文摘[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experiments were designed to optimize the extraction process of total flavonoids from P.chinense Pursh with the volume fraction of ethanol,the ratio of material to liquid,heating reflux extraction time and extraction times as factors,and the content of total flavonoids as the index.A verification test was carried out.The optimized extraction process was adopted to compare the contents of total flavonoids from different parts of P.chinense Pursh.[Results]The best extraction process was extracting the powder of P.chinense Pursh for 2.0 h with 20 times of 55%ethanol by reflux twice.Under this condition,the contents of total flavonoids were 3.63%,8.90%,11.28%,and 4.36%from stems,leaves,flowers and whole grass of P.chinense Pursh,respectively.[Conclusions]The process is reasonable,feasible and stable,and can effectively extract total flavonoids from P.chinense Pursh.The contents of total flavonoids from different parts of P.chinense Pursh were quite different,and the value was higher in the leaves and flowers,so the proportions of leaves and flowers should be paid attention to in the industrial processing of P.chinense Pursh.
基金Jining City Key R&D Program Projects(Project No.:2023YXNS155)。
文摘Rationale:Aortic dissection is a life-threatening medical emergency associated with high morbidity and mortality.Preoperative mesenteric malperfusion increases the surgical risk and mortality in patients with type B aortic dissection.For DeBakey type III B patients involving most of the thoracoabdominal aorta,endovascular treatment to improve true lumen perfusion may have limited benefits.Organ reperfusion on-time is crucial.Patient concerns:A 38-year-old man was admitted with sudden severe upper abdominal pain.Emergency CTA of the entire aorta revealed an aortic dissection with an entry tear in the descending aortic arch involving the celiac trunk,superior mesenteric artery,bilateral common iliac arteries and right external iliac artery,with thrombosis in the superior mesenteric artery.Diagnoses:The patient was diagnosed with DeBakey type III aortic dissection with mesenteric artery embolism.Enhanced chest CT showed the entry tear location and involvement of major arteries.Angiography confirmed partial blood flow in the superior mesenteric artery.Interventions:The patient underwent endovascular aortic stent-graft implantation through the left femoral artery,covering the descending aortic arch and sealing the entry tear.Postoperatively,the patient received intensive care,including ventilatory support,CRRT,anti-infection therapy,vasoactive drugs and lumbar cistern drainage.Outcomes:Two weeks postoperatively,the patient developed massive black stools,indicative of intestinal obstruction and necrosis.Exploratory laparotomy revealed ischemic necrosis and rupture of the stomach,small intestine,and colon.Despite surgical efforts,the patient’s condition deteriorated,leading to death from severe infection,acid-base imbalance and multiple organ failure.
基金the National Natural Science Foundation of China(Grant Nos.12004064,12074053,and 91961204)the Fundamental Research Funds for the Central Universities(Grant No.DUT22LK11)XingLiaoYingCai Project of Liaoning Province,China(Grant No.XLYC1907163)。
文摘Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface structure of Fe_(3)O_(4)at atomic scale.Here,using a combination of first-principles calculations,particle swarm optimization(PSO)method and machine learning,we investigate the possible reconstruction and stability of Fe_(3)O_(4)(001)surface.The results show that besides the subsurface cation vacancy(SCV)reconstruction,an A layer with Fe vacancy(A-layer-V_(Fe))reconstruction of the(001)surface also shows very low surface energy especially at oxygen poor condition.Molecular dynamics simulation based on the iron–oxygen interaction potential function fitted by machine learning further confirms the thermodynamic stability of the A-layer-V_(Fe)reconstruction.Our results are also instructive for the study of surface reconstruction of other metal oxides.
基金the National Natural Science Foundation of China(Nos.51805298 and 12072267)the Natural Science Foundation of Shandong Province of China(No.ZR2019PEE015)+3 种基金the Fundamental Research Funds for the Central Universities of China(No.2019ZRJC006)the 111 Project of China(No.BP0719007)the Innovation Capability Support Plan of Shaanxi Province of China(No.2020KJXX-021)the Young Scholars Program of Shandong University,Weihai of China(No.20820201004)。
文摘Piezoelectric energy harvesting is considered as an ideal power resource for low-power consumption gadgets in vibrational environments.The energy extraction efficiency depends highly on the interface circuit,and should be highly improved to meet the power requirements.The nonlinear interface circuits in discrete components have been extensively explored and developed with the advantages of easy implementation,stable operation,high efficiency,and low cost.This paper reviews the state-of-the-art progress of nonlinear piezoelectric energy harvesting interface circuits in discrete components.First,the working principles and the advantages/disadvantages of four classical interface circuits are described.Then,the improved circuits based on the four typical circuits and other types of circuits are introduced in detail,and the advantages/disadvantages,output power,efficiency,energy consumption,and practicability of these circuits are analyzed.Finally,the future development trends of nonlinear piezoelectric energy harvesting circuits,e.g.,self-powered extraction,low-power consumption,and broadband characteristic,are predicted.
基金supported by New and Old Energy Conversion Project of Jining City(2017ZDGH031)Guiding funds for the development of local science and technology by the Central government(2017106014)Natural Science Foundation of Liaoning Province(L2015317).
文摘Glioma is one of the lethal central nervous system tumors.The infiltrative and invasive growth nature makes it difficult to identify the boundary between glioma and the normal tissues,resulting in inevitable recurrence after surgery operation.Gliomas do not metastasize,so to prevent the residual tumor from proliferating or invading is a key challenge.Previous report indicated that hypotaurine could facilitate glioma invasion and suppress demethylases’activities.Using a hypotaurine synthesis deficient U251 cell line,we proved that the cells invasion ability was impaired.Gene expression profile analysis exhibited that knocking down one of the key enzymes of hypotaurine synthesis,2-aminoethanethiol dioxygenase(ADO),significantly affected the extracellular matrix-receptor process.Of that process,Wnt5a expression was severely upregulated by decreased intracellular ADO expression.Cells cultured at the presence of hypotaurine showed a decrease in intracellular Wnt5a protein and mRNA levels.This phenotype was due to hypermethylation of Wnt5a promoter,which was most likely the result of hypotaurine’s inhibiting demethylases activities.Collectively,this study demonstrated that hypotaurine synthesis deficient U251 cells were prone to epigenetic modification and Wnt5a seemed to be a tumor suppressor under that circumstance.This tumor suppression effect is warranted to be reevaluated in real tumor samples and the relevant evidence might contribute to develop new glioma interference strategies.
文摘Influenza-associated encephalopathy (IAE) can perform as varying patterns of neuroimaging. Central brain herniation (CBH) secondary to IAE is rare;it may be a bad prognosis. Here, we presented a 4-year-old girl with influenza who had a pontocerebellar hypoplasia (PCH) history;she performed the second Magnetic Resonance Imaging (MRI) on Day 6 from onset, showed the diffuse edema and the occurrence of central herniation;the medulla was “Z-like” folded and the basal cisterns were obliterated completely. Finally she was declared dead. The imbalance between supratentorial and infratentorial pressure can lead to the occurrence of CBH. Severe edema relates to IAE and unstable structure of the posterior fossa might be the main reason for the herniation. MRI is helpful in early diagnosis. Early treatment of cerebral edema in patients with congenital abnormalities of the posterior fossa is vital for their management.
文摘The swine flu, H1N1 virus was outbroken in Mexico and the United States in April 2009 and then rapidly spread worldwide. The World Health Organization declared that the outbreak of influenza is caused by a new subtype of influenza H1N1 influenza virus. And researchers have isolated some oseltamivir resistance strains in 2009 swine flu which makes the imminency of research and development of new anti influenza drug. The CPSF30 binding pocket of effector domain in NS1 protein is very important in the replication of influanza A virus and is a new attractive anti flu drug target. But up to now there is no antiviral drug target this pocket. Here we employ molecular docking to screening of about 200,000 compounds. We find four novel compounds with high binding energy. Binding comformation analysis revealed that these small molecules can interact with the binding pocket by some strong hydrophobic interaction. This study find some novel small molecules can be used as lead compounds in the development of new antiinfluenza drug based on CPSF30 pocket.
文摘OBJECTIVE To study the relationship between bFGF gene expression and proliferative activity in meningiomas. METHODS Thirty-seven samples of meningioma were examed using Northern hybridization for bFGF-gene expression and immunohistochemi- stry for bFGF protein expression and the Ki-67LI. RESULTS bFGF mRNA was detected in 22 meningiomas of Grade Ⅰ and in all samples of Grade Ⅱ and Ⅲ. Six of the Grade Ⅰ tumors were negative, giving an overall positive rate of 83.8 % for bFGF mRNA. Autoradiography was conducted using a thin scaning apparatus, bFGF mRNA expression compared to that for β-actin was 0.34±0.06 for Grade Ⅰ tumors compared to 0.82±0.12 for Grade Ⅱ and Ⅲ tumors. The difference was highly significant (P〈0.001). The results of immunohistochemistry showed that the number of the positive cells for the bFGF protein was 29.7±7.6% in Grade Ⅰ tumors and 63.2±11.7 % in Grade Ⅱ plus Ⅲ, resulting in a significant difference between them (P〈0.001) . The Ki-67LI was found to be 2.8±1.1% in Grade Ⅰ and 6.5±1.3 % in Grade Ⅱ plus Ⅲ. The former was significantly lower than the later (P〈0.001). CONCLUSION The expression of bFGF was correlated well with the malignancy of the meningiomas.
文摘Garcinia Glycosides is a candidate drug obtained by structural modification of Gambogic Acid (GA), which was acquired through High Throughput Screening(HTS). As Garcinia Glycosides is an effective but insoluble anti-tumor drug, the aim of this study was to obtain a solid dispersion form Garcinia Glycosides by using solvent-melt method so that improve the solubility and dissolution rate. The solid dispersion was characterized by High Performance Liquid Chromatography (HPLC), infrared spectroscopy and evaluated the intestinal absorption of the drug by rat in situ single pass intestinal perfusion. The results showed the increase of solubility, dissolution velocity and absorption compared to other forms. This indicated that solid dispersion could greatly improve the relative bioavailability of Garcinia Glycosides in vivo.
文摘Graphene-h-BN hybrid nanostructures are grown in one step on the Pt(111) surface by ultra-high vacuum chemical vapor deposition using a single precursor,the dimethylamino borane complex.By varying the deposition conditions,different nanostructures ranging from a fully continuous hybrid monolayer to well-separated Janus nanodots can be obtained.The growth starts with heterogeneous nucleation on morphological defects such as Pt step edges and proceeds by the addition of small clusters formed by the decomposition of the dimethylamino borane complex.Scanning tunneling microscopy measurements indicate that a sharp zigzag in-plane boundary is formed when graphene grows aligned with the Pt substrate and consequently with the h-BN layer as well.When graphene is rotated by 30°,the graphene armchair edges are seamlessly connected to h-BN zigzag edges.This is confirmed by a thorough density functional theory (DFT) study.Angle resolved photoemission spectroscopy (ARPES) data suggests that both h-BN and graphene present the typical electronic structure of self-standing non-interacting materials.
文摘Epidermal growth factor receptor (EGFR) mediates multiple signaling pathways that regulate cell migration, proliferation, and differentiation. Adaptor pro- tein APPL1 has been reported to function as a downstream effector of EGFR signaling pathway. However, molecular mechanisms underlying the role of APPL1 downstream of EGFR signaling remains elusive. Here, we identified APPL1 as a critical molecule that interacts with EGFR. Suppression of APPL 1 by siRNA inhibited EGF-stimulated Akt phosphorylation. Functionally, EGF stimulation of cells caused phosphorylation of APPL1 at Ser636, which subsequently promoted the interaction between APPL1 and EGFR, indicating that APPL1 sensitizes EGF stimulation by acting at a site downstream of the EGFR signaling. Importantly, non-phosphorylatable mutant of APPL1 reduced cell migration compared with wild-type APPL1 in an Akt-dependent manner. Our study reveals a novel function of APPL1 in EGF signaling and defines a novel molecular mechanism by which phosphorylation of APPL1 upon EGF stimulation regulates cell migration underlying EGF-stimulated Akt pathway.
基金Innovation Team Project(Grant No.LT2015011)from the Education Department of Liaoning ProvinceImportant Sci entific and Technical Achievements Transformation Project(Gr ant No.Z17-5-078)+1 种基金Applied Basic Research Project(Grant No.F16205144)of Science and Technology Bureau of Shenyangthe Liaoning Provincial Education Department Project of China(Grant No.L2015192)
文摘Total paeony glycoside(TPG) is obtained from Radix Paeoniae Rubra with a variety of bioactivities. However, the low solubility and bioavailability limit its application. The present study aimed to develop TPG nanocrystals to increase the dissolution and then improve the oral bioavailability. TPG nanocrystals were prepared via precipitation and high-pressure homogenization method. The physical-chemical properties of the optimal TPG nanocrystals in terms of particle size, zeta potential, morphology and crystallinity were evaluated. The results showed that TPG nanocrystals had a mean particle size of(210.2±2.5) nm, a polydispersity index of 0.191±0.033 and a zeta potential of(–22.4±1.2) mV. The result of differential scanning calorimetry showed that the nanocrystals were still in crystalline state after the preparation procedure. Transmission electron microscopy(TEM) results showed that the nanosuspension was in spherical shape. The pharmacokinetics of TPG nanocrystals for rats was investigated by liquid chromatography-tandem mass spectroscopy(LC-MS/MS). Compared with the TPG coarse suspension, TPG nanocrystals exhibited significant increase in AUC0–∞(approximately 1.85-fold). Taken together, TPG nanocrystals could be used as a promising drug delivery system due to the enhanced oral bioavailability of TPG.