Bone biomaterials have been increasingly used to reconstruct maxillary atrophic ridges.Thus,the aim of this study was to evaluate bone reconstruction in the maxilla using a homologous cortico-cancellous FFB(lyophilize...Bone biomaterials have been increasingly used to reconstruct maxillary atrophic ridges.Thus,the aim of this study was to evaluate bone reconstruction in the maxilla using a homologous cortico-cancellous FFB(lyophilized)graft and verify its reliability.Eight individuals were included from 2014 to 2018.The first surgery was performed to install homologous bone blocks in the maxilla.The period of the second intervention varied between 5 months and 15 days to 11 months(≈7.93 months).The biopsies were taken from the central region of the matured graft during the surgery for implant placement.All patients presented clinical and radiographic conditions for the installation of dental implants.There was a 100%of survival rate.The histological assessment showed that the homologous block bone graft was an osteoconductive biomaterial,with connective tissue present,and newly formed bone juxtaposed on its surface.There were bone trabeculae with osteocytes and active osteoblasts with connective tissue in the mineralization process;the remodeling process can be found through the reverse lines.A limited focus of necrosis with fibrosis was detected,with small resorption and areas of inflammatory infiltrate,but without clinical significance.The homologous block bone graft can be considered a feasible option to substitute the autogenous bone graft(gold standard),with predictable clinical and favorable histological results.The patients had a shorter surgical period,low morbidity,and an unlimited amount of biomaterial available at an accessible cost.展开更多
An importa nt strategy to promote voluntary movements after motor system injury is to strengthen the connections between the motor cortex and muscles by taking advantage of the plasticity of the corticospinal motor sy...An importa nt strategy to promote voluntary movements after motor system injury is to strengthen the connections between the motor cortex and muscles by taking advantage of the plasticity of the corticospinal motor system.Many neuromodulation approaches are directed to activate the spinal cord and peripheral axons to strengthen muscle activation.We discuss in this perspective that,the cortex and spinal cord should be ta rgeted together to enhance cortex-to-musclefunction(Amer and Martin,2022).展开更多
This paper investigates the concept of Cross Polarization (CP) experiment in addition to revisiting the two potential expansion schemes recently developed in the field of solid-state nuclear magnetic resonance (SSNMR)...This paper investigates the concept of Cross Polarization (CP) experiment in addition to revisiting the two potential expansion schemes recently developed in the field of solid-state nuclear magnetic resonance (SSNMR): namely, the Floquet-Magnus expansion and the Fer expansion. We use the aforementioned expansion schemes for the calculation of effective Hamiltonians and propagators when the spin system undergoes Cross Polarization radiation. CP is the gateway experiment into SSNMR. An in-depth comprehension of the underlying mechanics of spin dynamics during the cross-polarization experiment is pivotal for further experimental developments and optimization of more complex solid-state NMR experiments. The main contribution of this work is a prospect related to spin physics;particularly regarding to generalization of the calculation. This work reports original yet interesting novel ideas and developments that include calculations performed on the CP experiment. In fact, the approach presented could play a major role in the interpretation of several fine NMR experiments in solids, which would in turn provide significant new insights in spin physics. The generality of the work points towards potential applications in problems related in solid-state NMR and theoretical developments of spectroscopy as well as interdisciplinary research areas as long as they include spin dynamics concepts.展开更多
以3.5PbO.96.5B2O3(m o l%)玻璃作为研究对象,着重研究其在不同重力条件下的分相现象。该部分讨论了2个落塔实验试样发生分相的重力条件,同时分析了试样的相组成和试样成分的不均匀性。结果发现,该成分玻璃发生分相后形成的富硼相和富...以3.5PbO.96.5B2O3(m o l%)玻璃作为研究对象,着重研究其在不同重力条件下的分相现象。该部分讨论了2个落塔实验试样发生分相的重力条件,同时分析了试样的相组成和试样成分的不均匀性。结果发现,该成分玻璃发生分相后形成的富硼相和富铅相都是玻璃相。分相在高重力阶段发生的试样其成分均匀性最差,原因在于富硼相和富铅相间存在较大的密度差。展开更多
DNA mismatch repair (MMR) is a highly conserved biological pathway that plays a key role in maintaining genomic stability. The specificity of MMR is primarily for base-base mismatches and insertion/deletion mispairs...DNA mismatch repair (MMR) is a highly conserved biological pathway that plays a key role in maintaining genomic stability. The specificity of MMR is primarily for base-base mismatches and insertion/deletion mispairs generated during DNA replication and recombination. MMR also suppresses homeologous recombination and was recently shown to play a role in DNA damage signaling in eukaryotic cells. Escherichia coli MutS and MutL and their eukaryotic homologs, MutSα and MutLα, respectively, are key players in MMR-associated genome maintenance. Many other protein components that participate in various DNA metabolic pathways, such as PCNA and RPA, are also essential for MMR. Defects in MMR are associated with genome-wide instability, predisposition to certain types of cancer including hereditary non-polyposis colorectal cancer, resistance to certain chemotherapeutic agents, and abnormalities in meiosis and sterility in mammalian systems.展开更多
Hepatocellular carcinoma(HCC) is the most common primary malignancy of the liver. It is the second leading cause of cancer-related deaths worldwide, with a very poor prognosis. In the United States, there has been onl...Hepatocellular carcinoma(HCC) is the most common primary malignancy of the liver. It is the second leading cause of cancer-related deaths worldwide, with a very poor prognosis. In the United States, there has been only minimal improvement in the prognosis for HCC patients over the past 15 years. Details of the molecular mechanisms and other mechanisms of HCC progression remain unclear. Consequently, there is an urgent need for better understanding of these mechanisms. HCC is often diagnosed at advanced stages, and most patients will therefore need systemic therapy, with sorafenib being the most common at the present time. However, sorafenib therapy only minimally enhances patient survival. This review provides a summary of some of the known mechanisms that either cause HCC or contribute to its progression. Included in this review are the roles of viral hepatitis, non-viral hepatitis, chronic alcohol intake, genetic predisposition and congenital abnormalities, toxic exposures, and autoimmune diseases of the liver. Well-established molecular mechanisms of HCC progression such as epithelial-mesenchymal transition, tumor-stromal interactions and the tumor microenvironment, cancer stem cells, and senescence bypass are also discussed. Additionally, we discuss the roles of circulating tumor cells,immunomodulation, and neural regulation as potential new mechanisms of HCC progression. A better understanding of these mechanisms could have implications for the development of novel and more effective therapeutic and prognostic strategies, which are critically needed.展开更多
The neuropeptide hormone oxytocin, which is released from the posterior pituitary gland, is involved in a number of physiological processes. Understanding of its effects is gradually increasing due to new research in ...The neuropeptide hormone oxytocin, which is released from the posterior pituitary gland, is involved in a number of physiological processes. Understanding of its effects is gradually increasing due to new research in this area. While mostly recognized as a reproductive system hormone, oxytocin also regulates other organ systems such as the brain and cardiovascular system. Recently, research has focused on unraveling its involvement in cancer, and emerging evidence suggests a potential role for oxytocin as a cancer biomarker. This review summarizes observations linking oxytocin and cancer, with a special emphasis on prostate cancer, where it may promote cell proliferation. Research suggests that oxytocin effects may depend on cell type, concentration of the hormone, its interactions with other hormones in the microenvironment, and the precise localization of its receptor on the cell membrane. Future research is needed to further elucidate the involvement of oxytocin in cancer, and whether it could be a clinical cancer biomarker or therapeutic target.展开更多
Vascular depression(VD)as defined by magnetic resonance imaging(MRI)has been proposed as a unique subtype of late-life depression.The VD hypothesis posits that cerebrovascular disease,as characterized by the presence ...Vascular depression(VD)as defined by magnetic resonance imaging(MRI)has been proposed as a unique subtype of late-life depression.The VD hypothesis posits that cerebrovascular disease,as characterized by the presence of MRIdefined white matter hyperintensities,contributes to and increases the risk for depression in older adults.VD is also accompanied by cognitive impairment and poor antidepressant treatment response.The VD diagnosis relies on MRI findings and yet this clinical entity is largely unfamiliar to neuroradiologists and is rarely,if ever,discussed in radiology journals.The primary purpose of this review is to introduce the MRI-defined VD construct to the neuroradiology community.Case reports are highlighted in order to illustrate the profile of VD in terms of radiological,clinical,and neuropsychological findings.A secondary purpose is to elucidate and elaborate on the measurement of cerebrovascular disease through visual rating scales and semi-and fully-automated volumetric methods.These methods are crucial for determining whether lesion burden or lesion severity is the dominant pathological contributor to VD.Additionally,these rating methods have implications for the growing field of computer assisted diagnosis.Since VD has been found to have a profile that is distinct from other types of late-life depression,neuroradiologists,in conjunction with psychiatrists and psychologists,should consider VD in diagnosis and treatment planning.展开更多
The kernel energy method(KEM) has been shown to provide fast and accurate molecular energy calculations for molecules at their equilibrium geometries.KEM breaks a molecule into smaller subsets,called kernels,for the p...The kernel energy method(KEM) has been shown to provide fast and accurate molecular energy calculations for molecules at their equilibrium geometries.KEM breaks a molecule into smaller subsets,called kernels,for the purposes of calculation.The results from the kernels are summed according to an expression characteristic of KEM to obtain the full molecule energy.A generalization of the kernel expansion to density matrices provides the full molecule density matrix and orbitals.In this study,the kernel expansion for the density matrix is examined in the context of density functional theory(DFT) Kohn-Sham(KS) calculations.A kernel expansion for the one-body density matrix analogous to the kernel expansion for energy is defined,and is then converted into a normalizedprojector by using the Clinton algorithm.Such normalized projectors are factorizable into linear combination of atomic orbitals(LCAO) matrices that deliver full-molecule Kohn-Sham molecular orbitals in the atomic orbital basis.Both straightforward KEM energies and energies from a normalized,idempotent density matrix obtained from a density matrix kernel expansion to which the Clinton algorithm has been applied are compared to reference energies obtained from calculations on the full system without any kernel expansion.Calculations were performed both for a simple proof-of-concept system consisting of three atoms in a linear configuration and for a water cluster consisting of twelve water molecules.In the case of the proof-of-concept system,calculations were performed using the STO-3 G and6-31 G(d,p) bases over a range of atomic separations,some very far from equilibrium.The water cluster was calculated in the 6-31 G(d,p) basis at an equilibrium geometry.The normalized projector density energies are more accurate than the straightforward KEM energy results in nearly all cases.In the case of the water cluster,the energy of the normalized projector is approximately four times more accurate than the straightforward KEM energy result.The KS density matrices of this study are applicable to quantum crystallography.展开更多
Flaviviruses, ss(+) RNA viruses, include many of mankind's most important pathogens. Their pathogenicity derives from their ability to infect many types of cells including neurons, to replicate, and eventually to ...Flaviviruses, ss(+) RNA viruses, include many of mankind's most important pathogens. Their pathogenicity derives from their ability to infect many types of cells including neurons, to replicate, and eventually to kill the cells. Flaviviruses can activate tumor necrosis factor α and both intrinsic(Bax-mediated) and extrinsic pathways to apoptosis. Thus they can use many approaches for activating these pathways. Infection can lead to necrosis if viral load is extremely high or to other types of cell death if routes to apoptosis are blocked. Dengue and Japanese Encephalitis Virus can also activate autophagy. In this case the autophagy temporarily spares the infected cell, allowing a longer period of reproduction for the virus, and the autophagy further protects the cell against other stresses such as those caused by reactive oxygen species. Several of the viral proteins have been shown to induce apoptosis or autophagy on their own, independent of the presence of other viral proteins. Given the versatility of these viruses to adapt to and manipulate the metabolism, and thus to control the survival of, the infected cells, we need to understand much better how the specific viral proteins affect the pathways to apoptosis and autophagy. Only in this manner will we be able to minimize the pathology that they cause.展开更多
Plant cuticle,which covers the plant surface,consists of waxes and cutins,and is associated with plant drought,cold,and salt resistance.Hitherto,at least 47 genes participating in the formation of plant cuticle have b...Plant cuticle,which covers the plant surface,consists of waxes and cutins,and is associated with plant drought,cold,and salt resistance.Hitherto,at least 47 genes participating in the formation of plant cuticle have been cloned from Arabidopsis thaliana,Oryza sativa,Zea mays,Ricinus communis,Brassica napus,and Medicago truncatula;and about 85% of them encode proteins sharing above 50% identities with their rice homologous sequences.These cloned cuticle genes were mapped in silico on different chromosomes of rice and Arabidopsis,respectively.The mapping results revealed that plant cuticle genes were not evenly distributed in both genomes.About 40% of the mapped cuticle genes were located on chromosome 1 in Arabidopsis,while 20% of the mapped cuticle genes were located on chromosome 2 but none on chromosome 12 in rice.Some cloned plant cuticle genes have several rice homologous sequences,which might be produced by chromosomal segment duplication.The consensus map of cloned plant cuticle genes will provide important clues for the selection of candidate genes in a positional cloning of an unknown cuticle gene in plants.展开更多
We present the feasibility study of nonlinear dielectrics for the energy storage applications. Corona deposition of electric charges to the surface of thin films of highly polarizable organic molecules (dielectrophore...We present the feasibility study of nonlinear dielectrics for the energy storage applications. Corona deposition of electric charges to the surface of thin films of highly polarizable organic molecules (dielectrophores) shows that the electric field inside the dielectric has a highly nonlinear response. The stored energy densities are superior to the polypropylene films, measured for the comparison, and at least comparable to the current electrochemical batteries. These results make us believe that the dielectrophores-based electrostatic capacitors can revolutionize the energy storage market.展开更多
Based on two mitochondrial genes (cyt b, ND4) and one nuclear gene (c-mos), we explored the relationships within the Asian pit viper genus Gloydius. In total, 23 samples representing 10 species were analyzed. All phyl...Based on two mitochondrial genes (cyt b, ND4) and one nuclear gene (c-mos), we explored the relationships within the Asian pit viper genus Gloydius. In total, 23 samples representing 10 species were analyzed. All phylogenetic analyses support a monophyletic Gloydius with two major clades, one comprising G. brevicaudus, G. blomhoffii, and G. ussuriensis with the sister clade consisting of G. intermedius, G. saxatilis, G. halys and G. shedaoensis. The relationships among the three montane species G. strauchi, G. qinlingensis and G. liupanensis, as well as the two monophyletic groups, are unstable, and discussed. Divergence date estimation indicates that Gloydius lineage formed 15 Ma and diversification of the genus occurred at 9.89 Ma. Issues regarding the taxonomy of this genus are discussed where necessary.展开更多
Background:Oxytocin(OXT)and its receptor(OXTR)is associated with cancer.The present study was to investigate the correlation between the genetic expression alterations of OXT and OXTR and the outcomes in patients with...Background:Oxytocin(OXT)and its receptor(OXTR)is associated with cancer.The present study was to investigate the correlation between the genetic expression alterations of OXT and OXTR and the outcomes in patients with pancreatic cancer(PC).Methods:Information regarding OXT and OXTR genetic alterations and changes in gene expression were retrieved from the Cancer Genome Atlas(TCGA)databases and analyzed using the cBioPortal online tool.We assessed the correlation of overall survival and disease/progression-free months to either OXT or OXTR genetic alterations and changes in gene expression using Kaplan-Meier and Cox regression anal-yses.Quantitative PCR(qPCR)was conducted to assess the mRNA expression levels of OXT and OXTR in human PC cell lines.Results:Five percent of PC cases showed mRNA upregulation in the OXT gene.These PC cases also showed genetic alterations and changes in gene expression of OXTR.The median months of survival and disease-free survival were lower for PC cases with genetic alterations and changes in gene expression in the OXT and OXTR genes as compared to those without such alterations.qPCR data showed that OXT and OXTR mRNA expression were 1-fold and 10-fold higher,respectively in PANC-1 cell lines as compared to L3.6pl cell lines in direct negative correlation with responsiveness to gemcitabine.Conclusions:These data suggest that OXT and OXTR may potentially be important in PC progression,chemoresistance,and patient survival,and potentially could have prognostic and therapeutic implications in a subset of PC patients.展开更多
文摘Bone biomaterials have been increasingly used to reconstruct maxillary atrophic ridges.Thus,the aim of this study was to evaluate bone reconstruction in the maxilla using a homologous cortico-cancellous FFB(lyophilized)graft and verify its reliability.Eight individuals were included from 2014 to 2018.The first surgery was performed to install homologous bone blocks in the maxilla.The period of the second intervention varied between 5 months and 15 days to 11 months(≈7.93 months).The biopsies were taken from the central region of the matured graft during the surgery for implant placement.All patients presented clinical and radiographic conditions for the installation of dental implants.There was a 100%of survival rate.The histological assessment showed that the homologous block bone graft was an osteoconductive biomaterial,with connective tissue present,and newly formed bone juxtaposed on its surface.There were bone trabeculae with osteocytes and active osteoblasts with connective tissue in the mineralization process;the remodeling process can be found through the reverse lines.A limited focus of necrosis with fibrosis was detected,with small resorption and areas of inflammatory infiltrate,but without clinical significance.The homologous block bone graft can be considered a feasible option to substitute the autogenous bone graft(gold standard),with predictable clinical and favorable histological results.The patients had a shorter surgical period,low morbidity,and an unlimited amount of biomaterial available at an accessible cost.
文摘An importa nt strategy to promote voluntary movements after motor system injury is to strengthen the connections between the motor cortex and muscles by taking advantage of the plasticity of the corticospinal motor system.Many neuromodulation approaches are directed to activate the spinal cord and peripheral axons to strengthen muscle activation.We discuss in this perspective that,the cortex and spinal cord should be ta rgeted together to enhance cortex-to-musclefunction(Amer and Martin,2022).
文摘This paper investigates the concept of Cross Polarization (CP) experiment in addition to revisiting the two potential expansion schemes recently developed in the field of solid-state nuclear magnetic resonance (SSNMR): namely, the Floquet-Magnus expansion and the Fer expansion. We use the aforementioned expansion schemes for the calculation of effective Hamiltonians and propagators when the spin system undergoes Cross Polarization radiation. CP is the gateway experiment into SSNMR. An in-depth comprehension of the underlying mechanics of spin dynamics during the cross-polarization experiment is pivotal for further experimental developments and optimization of more complex solid-state NMR experiments. The main contribution of this work is a prospect related to spin physics;particularly regarding to generalization of the calculation. This work reports original yet interesting novel ideas and developments that include calculations performed on the CP experiment. In fact, the approach presented could play a major role in the interpretation of several fine NMR experiments in solids, which would in turn provide significant new insights in spin physics. The generality of the work points towards potential applications in problems related in solid-state NMR and theoretical developments of spectroscopy as well as interdisciplinary research areas as long as they include spin dynamics concepts.
文摘以3.5PbO.96.5B2O3(m o l%)玻璃作为研究对象,着重研究其在不同重力条件下的分相现象。该部分讨论了2个落塔实验试样发生分相的重力条件,同时分析了试样的相组成和试样成分的不均匀性。结果发现,该成分玻璃发生分相后形成的富硼相和富铅相都是玻璃相。分相在高重力阶段发生的试样其成分均匀性最差,原因在于富硼相和富铅相间存在较大的密度差。
文摘DNA mismatch repair (MMR) is a highly conserved biological pathway that plays a key role in maintaining genomic stability. The specificity of MMR is primarily for base-base mismatches and insertion/deletion mispairs generated during DNA replication and recombination. MMR also suppresses homeologous recombination and was recently shown to play a role in DNA damage signaling in eukaryotic cells. Escherichia coli MutS and MutL and their eukaryotic homologs, MutSα and MutLα, respectively, are key players in MMR-associated genome maintenance. Many other protein components that participate in various DNA metabolic pathways, such as PCNA and RPA, are also essential for MMR. Defects in MMR are associated with genome-wide instability, predisposition to certain types of cancer including hereditary non-polyposis colorectal cancer, resistance to certain chemotherapeutic agents, and abnormalities in meiosis and sterility in mammalian systems.
文摘Hepatocellular carcinoma(HCC) is the most common primary malignancy of the liver. It is the second leading cause of cancer-related deaths worldwide, with a very poor prognosis. In the United States, there has been only minimal improvement in the prognosis for HCC patients over the past 15 years. Details of the molecular mechanisms and other mechanisms of HCC progression remain unclear. Consequently, there is an urgent need for better understanding of these mechanisms. HCC is often diagnosed at advanced stages, and most patients will therefore need systemic therapy, with sorafenib being the most common at the present time. However, sorafenib therapy only minimally enhances patient survival. This review provides a summary of some of the known mechanisms that either cause HCC or contribute to its progression. Included in this review are the roles of viral hepatitis, non-viral hepatitis, chronic alcohol intake, genetic predisposition and congenital abnormalities, toxic exposures, and autoimmune diseases of the liver. Well-established molecular mechanisms of HCC progression such as epithelial-mesenchymal transition, tumor-stromal interactions and the tumor microenvironment, cancer stem cells, and senescence bypass are also discussed. Additionally, we discuss the roles of circulating tumor cells,immunomodulation, and neural regulation as potential new mechanisms of HCC progression. A better understanding of these mechanisms could have implications for the development of novel and more effective therapeutic and prognostic strategies, which are critically needed.
文摘The neuropeptide hormone oxytocin, which is released from the posterior pituitary gland, is involved in a number of physiological processes. Understanding of its effects is gradually increasing due to new research in this area. While mostly recognized as a reproductive system hormone, oxytocin also regulates other organ systems such as the brain and cardiovascular system. Recently, research has focused on unraveling its involvement in cancer, and emerging evidence suggests a potential role for oxytocin as a cancer biomarker. This review summarizes observations linking oxytocin and cancer, with a special emphasis on prostate cancer, where it may promote cell proliferation. Research suggests that oxytocin effects may depend on cell type, concentration of the hormone, its interactions with other hormones in the microenvironment, and the precise localization of its receptor on the cell membrane. Future research is needed to further elucidate the involvement of oxytocin in cancer, and whether it could be a clinical cancer biomarker or therapeutic target.
文摘Vascular depression(VD)as defined by magnetic resonance imaging(MRI)has been proposed as a unique subtype of late-life depression.The VD hypothesis posits that cerebrovascular disease,as characterized by the presence of MRIdefined white matter hyperintensities,contributes to and increases the risk for depression in older adults.VD is also accompanied by cognitive impairment and poor antidepressant treatment response.The VD diagnosis relies on MRI findings and yet this clinical entity is largely unfamiliar to neuroradiologists and is rarely,if ever,discussed in radiology journals.The primary purpose of this review is to introduce the MRI-defined VD construct to the neuroradiology community.Case reports are highlighted in order to illustrate the profile of VD in terms of radiological,clinical,and neuropsychological findings.A secondary purpose is to elucidate and elaborate on the measurement of cerebrovascular disease through visual rating scales and semi-and fully-automated volumetric methods.These methods are crucial for determining whether lesion burden or lesion severity is the dominant pathological contributor to VD.Additionally,these rating methods have implications for the growing field of computer assisted diagnosis.Since VD has been found to have a profile that is distinct from other types of late-life depression,neuroradiologists,in conjunction with psychiatrists and psychologists,should consider VD in diagnosis and treatment planning.
文摘The kernel energy method(KEM) has been shown to provide fast and accurate molecular energy calculations for molecules at their equilibrium geometries.KEM breaks a molecule into smaller subsets,called kernels,for the purposes of calculation.The results from the kernels are summed according to an expression characteristic of KEM to obtain the full molecule energy.A generalization of the kernel expansion to density matrices provides the full molecule density matrix and orbitals.In this study,the kernel expansion for the density matrix is examined in the context of density functional theory(DFT) Kohn-Sham(KS) calculations.A kernel expansion for the one-body density matrix analogous to the kernel expansion for energy is defined,and is then converted into a normalizedprojector by using the Clinton algorithm.Such normalized projectors are factorizable into linear combination of atomic orbitals(LCAO) matrices that deliver full-molecule Kohn-Sham molecular orbitals in the atomic orbital basis.Both straightforward KEM energies and energies from a normalized,idempotent density matrix obtained from a density matrix kernel expansion to which the Clinton algorithm has been applied are compared to reference energies obtained from calculations on the full system without any kernel expansion.Calculations were performed both for a simple proof-of-concept system consisting of three atoms in a linear configuration and for a water cluster consisting of twelve water molecules.In the case of the proof-of-concept system,calculations were performed using the STO-3 G and6-31 G(d,p) bases over a range of atomic separations,some very far from equilibrium.The water cluster was calculated in the 6-31 G(d,p) basis at an equilibrium geometry.The normalized projector density energies are more accurate than the straightforward KEM energy results in nearly all cases.In the case of the water cluster,the energy of the normalized projector is approximately four times more accurate than the straightforward KEM energy result.The KS density matrices of this study are applicable to quantum crystallography.
基金Supported by NIAID NIH grant to Zakeri Z,No.1R15AIO94351-01the NIH NIGMS(MARC-USTAR),No.T 34 GM070387
文摘Flaviviruses, ss(+) RNA viruses, include many of mankind's most important pathogens. Their pathogenicity derives from their ability to infect many types of cells including neurons, to replicate, and eventually to kill the cells. Flaviviruses can activate tumor necrosis factor α and both intrinsic(Bax-mediated) and extrinsic pathways to apoptosis. Thus they can use many approaches for activating these pathways. Infection can lead to necrosis if viral load is extremely high or to other types of cell death if routes to apoptosis are blocked. Dengue and Japanese Encephalitis Virus can also activate autophagy. In this case the autophagy temporarily spares the infected cell, allowing a longer period of reproduction for the virus, and the autophagy further protects the cell against other stresses such as those caused by reactive oxygen species. Several of the viral proteins have been shown to induce apoptosis or autophagy on their own, independent of the presence of other viral proteins. Given the versatility of these viruses to adapt to and manipulate the metabolism, and thus to control the survival of, the infected cells, we need to understand much better how the specific viral proteins affect the pathways to apoptosis and autophagy. Only in this manner will we be able to minimize the pathology that they cause.
基金supported by the One Hundred Talents Project of the Chinese Academy of Sciences (O827751001)the National Natural Science Foundation of China(30970449)
文摘Plant cuticle,which covers the plant surface,consists of waxes and cutins,and is associated with plant drought,cold,and salt resistance.Hitherto,at least 47 genes participating in the formation of plant cuticle have been cloned from Arabidopsis thaliana,Oryza sativa,Zea mays,Ricinus communis,Brassica napus,and Medicago truncatula;and about 85% of them encode proteins sharing above 50% identities with their rice homologous sequences.These cloned cuticle genes were mapped in silico on different chromosomes of rice and Arabidopsis,respectively.The mapping results revealed that plant cuticle genes were not evenly distributed in both genomes.About 40% of the mapped cuticle genes were located on chromosome 1 in Arabidopsis,while 20% of the mapped cuticle genes were located on chromosome 2 but none on chromosome 12 in rice.Some cloned plant cuticle genes have several rice homologous sequences,which might be produced by chromosomal segment duplication.The consensus map of cloned plant cuticle genes will provide important clues for the selection of candidate genes in a positional cloning of an unknown cuticle gene in plants.
文摘We present the feasibility study of nonlinear dielectrics for the energy storage applications. Corona deposition of electric charges to the surface of thin films of highly polarizable organic molecules (dielectrophores) shows that the electric field inside the dielectric has a highly nonlinear response. The stored energy densities are superior to the polypropylene films, measured for the comparison, and at least comparable to the current electrochemical batteries. These results make us believe that the dielectrophores-based electrostatic capacitors can revolutionize the energy storage market.
基金partially funded by the National Natural Science Foundation of China(NSFC 30870290,NSFC 30970334,NSFC 31071892)the Program for New Century Excellent Talents in University(NCET-08-0908)
文摘Based on two mitochondrial genes (cyt b, ND4) and one nuclear gene (c-mos), we explored the relationships within the Asian pit viper genus Gloydius. In total, 23 samples representing 10 species were analyzed. All phylogenetic analyses support a monophyletic Gloydius with two major clades, one comprising G. brevicaudus, G. blomhoffii, and G. ussuriensis with the sister clade consisting of G. intermedius, G. saxatilis, G. halys and G. shedaoensis. The relationships among the three montane species G. strauchi, G. qinlingensis and G. liupanensis, as well as the two monophyletic groups, are unstable, and discussed. Divergence date estimation indicates that Gloydius lineage formed 15 Ma and diversification of the genus occurred at 9.89 Ma. Issues regarding the taxonomy of this genus are discussed where necessary.
基金supported by a grant from the National Cancer Institute(No.U54CA221704).
文摘Background:Oxytocin(OXT)and its receptor(OXTR)is associated with cancer.The present study was to investigate the correlation between the genetic expression alterations of OXT and OXTR and the outcomes in patients with pancreatic cancer(PC).Methods:Information regarding OXT and OXTR genetic alterations and changes in gene expression were retrieved from the Cancer Genome Atlas(TCGA)databases and analyzed using the cBioPortal online tool.We assessed the correlation of overall survival and disease/progression-free months to either OXT or OXTR genetic alterations and changes in gene expression using Kaplan-Meier and Cox regression anal-yses.Quantitative PCR(qPCR)was conducted to assess the mRNA expression levels of OXT and OXTR in human PC cell lines.Results:Five percent of PC cases showed mRNA upregulation in the OXT gene.These PC cases also showed genetic alterations and changes in gene expression of OXTR.The median months of survival and disease-free survival were lower for PC cases with genetic alterations and changes in gene expression in the OXT and OXTR genes as compared to those without such alterations.qPCR data showed that OXT and OXTR mRNA expression were 1-fold and 10-fold higher,respectively in PANC-1 cell lines as compared to L3.6pl cell lines in direct negative correlation with responsiveness to gemcitabine.Conclusions:These data suggest that OXT and OXTR may potentially be important in PC progression,chemoresistance,and patient survival,and potentially could have prognostic and therapeutic implications in a subset of PC patients.