Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in hu...Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury.展开更多
The present paper covers the unprecedented preparation of stable aqueous Dy-ferrite ferrofluids, whereby colloidal Dy_ δ Fe_ 3- δ O_4 ultrafine particles were dispersed by using polymeric surfactant PMAA. The sta...The present paper covers the unprecedented preparation of stable aqueous Dy-ferrite ferrofluids, whereby colloidal Dy_ δ Fe_ 3- δ O_4 ultrafine particles were dispersed by using polymeric surfactant PMAA. The stabilities of the series of the ferrofluids were studied according to the stability indexes. The susceptibility measurements were made with a Farady-type magnetic balance at various temperatures and magnetic field intensities. In terms of Langevin function, the σ versus H/T curves showed that Dy-ferrite ferrofluids exhibited superparamagnetism behavior and the blocking temperatures were in the range from 160 to 200 K. Moreover, the ferrofluids were characterized by means of Infra-red spectroscopy, transmission electron microscopy, X-ray diffraction, and Mssbauer spectroscopy.展开更多
Solid solution of spinel ferrite Cu1-xZnxFe2-yGayO4 with (0.0≤x≤0.5 and y=0.1) are synthesized. XRD measurements confirm the presence of single-phase tetragonal structure with c/a>1 for CuFe2O4 and samples with (...Solid solution of spinel ferrite Cu1-xZnxFe2-yGayO4 with (0.0≤x≤0.5 and y=0.1) are synthesized. XRD measurements confirm the presence of single-phase tetragonal structure with c/a>1 for CuFe2O4 and samples with (x=0.0 and 0.1). The tetragonal phase is attributed to the presence of the cooperative Jahn-Teller Cu ions in the octahedral B-site in the spinel lattice. Tetragonal-to-cubic transformation is occurred at the compositional parameter x≥0.2 and the lattice parameter a is found to decrease with increasing Zn content x. 57Fe Mssbauer measurements at 293K for these compounds reveal superparamagnetic phase for samples with (0.0≤x≤0.2). In contrast,Mssbauer spectra at 12K for these materials show well ordered spectra where,the cation distribution and the hyperfine parameters are determined.展开更多
Ultrasmall superparamagnetic iron oxide nanoparticles(usSPIONs)are promising alternatives to gadolinium‐based contrast agents for positive contrast enhancement in magnetic resonance imaging(MRI).Unlike larger SPIONs ...Ultrasmall superparamagnetic iron oxide nanoparticles(usSPIONs)are promising alternatives to gadolinium‐based contrast agents for positive contrast enhancement in magnetic resonance imaging(MRI).Unlike larger SPIONs that primarily function as T2/T2*negative contrast agents,usSPIONs with core diameters below 5 nm can effectively shorten T1 relaxation times,producing bright signals in T1‐weighted images.This distinct behavior stems from their unique magnetic properties,including single‐domain configurations,surface spin canting,and rapid Néel relaxation dynamics,which are particularly enhanced at low magnetic field strengths.The biocompatibility of iron oxide,efficient renal clearance pathways,and versatility for surface functionalization offer potential advantages over gadolinium‐based agents,especially regarding safety concerns related to nephrogenic systemic fibrosis and gadolinium deposition.These nanoparticles show particular promise for applications in lowfield MRI,vascular imaging,targeted molecular imaging,and theranostic platforms.Although challenges remain in optimizing synthesis methods for consistent production of monodisperse usSPIONs with tailored surface chemistry,ongoing research continues to advance their potential for clinical translation.This review explores the mechanisms,synthesis approaches,applications,and future perspectives of usSPIONs as positive contrast agents in MRI.展开更多
The characte rization of MgFe_(2)O_(4)@CeO_(2) superparamagnetic nanocomposites was tho roughly investigated using powder X-ray diffraction(XRD),a vibrating sample magnetometer(VSM),scanning electron microscopy(SEM),d...The characte rization of MgFe_(2)O_(4)@CeO_(2) superparamagnetic nanocomposites was tho roughly investigated using powder X-ray diffraction(XRD),a vibrating sample magnetometer(VSM),scanning electron microscopy(SEM),dispersive X-ray analysis(EDX),elemental mapping(MAP),transmission electron microscopy(TEM),Brunauer-Emmett-Teller(BET) and UV-Vis diffuse reflectance spectroscopy(DRS)analyses.The photocatalytic activity of the synthesized samples was evaluated as a novel magnetic nanocatalyst for degrading Congo red(CR) dye in an aqueous solution under visible light at room conditions.The results demonstrate that the efficiency of photocatalytic degradation is higher than that of absorbance and photolysis.The degradation efficiency of photodegradation is 93% within 49% of total organic carbon removal performance.The prepared MgFe_(2)O_(4)@CeO_(2) magnetic nanocomposites(MNCs)can be easily recovered and recycled for five repeated cycles,demonstrating potential extensive efficiency in magnetic nanocomposites in wastewater and water treatment.The nanoscale morphology of MgFe_(2)O_(4)@CeO_(2) MNCs was characterized as spherical,with a size range of 35-40 nm,utilizing SEM and TEM techniques.The saturation magnetization(M_(s)) of the resulting nanocomposites was analyzed by VSM,revealing a value of 3.58 emu/g.Furthermore,the surface area was determined to be 27.194 m^(2)/g using BET analysis,and the band gap was identified as 2.85 eV through DRS analysis.展开更多
Magnetic stimulation has made significant strides in the treatment of psychiatric disorders.Nonetheless,current magnetic stimulation techniques lack the precision to accurately modulate specific nuclei and cannot real...Magnetic stimulation has made significant strides in the treatment of psychiatric disorders.Nonetheless,current magnetic stimulation techniques lack the precision to accurately modulate specific nuclei and cannot realize deep brain magnetic stimulation.To address this,we utilized superparamagnetic iron oxide nanoparticles as mediators to achieve precise targeting and penetration.We investigated the effects of magnetic fields with varying frequencies on neuronal activity and compared the activation effects on neurons using a 10-Hz precise magneto-stimulation system(pMSS)with repetitive transcranial magnetic stimulation in mice.Oxytocin levels,dendritic morphology and density,and mouse behavior were measured before and after pMSS intervention.Our findings suggest that pMSS can activate oxytocinergic neurons,leading to upregulation of oxytocin secretion and neurite outgrowth.As a result,sociability was rapidly improved after a one-week pMSS treatment regimen.These results demonstrate a promising magneto-stimulation method for regulating neuronal activity in deep brain nuclei and provide a promising therapeutic approach for autism spectrum disorder.展开更多
Glioblastoma multiforme(GBM)is a highly aggressive and lethal brain tumor with limited treatment options.To improve therapeutic efficacy,we developed a novel multifunctional nanoplatform,GM@P(T/S),comprised of polymer...Glioblastoma multiforme(GBM)is a highly aggressive and lethal brain tumor with limited treatment options.To improve therapeutic efficacy,we developed a novel multifunctional nanoplatform,GM@P(T/S),comprised of polymeric nanoparticles coated with GBM cell membranes as well as co-loaded with temozolomide(TMZ)and superparamagnetic iron oxide(SPIO)nanoparticles.The successful preparation was confirmed in terms of particle size,morphology,stability,the in vitro drug release,and cellular uptake assays.We demonstrated that GM@P(T/S)exhibited the enhanced homotypic targeting,the prolonged blood circulation,and efficient bloodbrain barrier penetration in both in vitro and in vivo studies.The combination of TMZ and SPIO nanoparticles within GM@P(T/S)synergistically improved chemo-radiation therapy,leading to a reduced tumor growth,an increased survival,and minimal systemic toxicity in the orthotopic GBM mouse models.Our findings suggest that GM@P(T/S)holds a great promise as a targeted and efficient therapeutic strategy for GBM.展开更多
The present paper covers a novel technology for the concentration of trace amounts of target oligonucleotide from the solution. This technique is based on a super-paramagnetic DNA nano-enricher constructed with a sing...The present paper covers a novel technology for the concentration of trace amounts of target oligonucleotide from the solution. This technique is based on a super-paramagnetic DNA nano-enricher constructed with a single strand DNA probe immobilized onto the surface of the super-paramagnetic nanoparticles prepared by using the water-in-oil microemulsion technique, employing silica as the shell and iron oxide as the core of the super-paramagnetic nanoparticles. The silica coated magnetic nanoparticles are (40±4) nm in size. And the magnetic nanoparticle is super-paramagnetic. Biotin labeled ssDNA(Biotin-5-(A)10-GAT-TCA-CGA-GGC-CCT-AGT-CG-3) was immobilized on the surface of silica coated magnetic nanoparticles. The complementary ssDNA could be enriched effectively and the characteristics of the enriched ssDNA have not changed, which will provide a novel technique and measurement for gene transfection, mutation detection, gene diagnosis, gene therapy and so on.展开更多
基金supported by the National Key R&D Program of China,Nos.2017YFA0104302(to NG and XM)and 2017YFA0104304(to BW and ZZ)
文摘Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury.
基金Supported by the National Natural Science Foundation of China(No.2 97730 14)
文摘The present paper covers the unprecedented preparation of stable aqueous Dy-ferrite ferrofluids, whereby colloidal Dy_ δ Fe_ 3- δ O_4 ultrafine particles were dispersed by using polymeric surfactant PMAA. The stabilities of the series of the ferrofluids were studied according to the stability indexes. The susceptibility measurements were made with a Farady-type magnetic balance at various temperatures and magnetic field intensities. In terms of Langevin function, the σ versus H/T curves showed that Dy-ferrite ferrofluids exhibited superparamagnetism behavior and the blocking temperatures were in the range from 160 to 200 K. Moreover, the ferrofluids were characterized by means of Infra-red spectroscopy, transmission electron microscopy, X-ray diffraction, and Mssbauer spectroscopy.
文摘Solid solution of spinel ferrite Cu1-xZnxFe2-yGayO4 with (0.0≤x≤0.5 and y=0.1) are synthesized. XRD measurements confirm the presence of single-phase tetragonal structure with c/a>1 for CuFe2O4 and samples with (x=0.0 and 0.1). The tetragonal phase is attributed to the presence of the cooperative Jahn-Teller Cu ions in the octahedral B-site in the spinel lattice. Tetragonal-to-cubic transformation is occurred at the compositional parameter x≥0.2 and the lattice parameter a is found to decrease with increasing Zn content x. 57Fe Mssbauer measurements at 293K for these compounds reveal superparamagnetic phase for samples with (0.0≤x≤0.2). In contrast,Mssbauer spectra at 12K for these materials show well ordered spectra where,the cation distribution and the hyperfine parameters are determined.
文摘Ultrasmall superparamagnetic iron oxide nanoparticles(usSPIONs)are promising alternatives to gadolinium‐based contrast agents for positive contrast enhancement in magnetic resonance imaging(MRI).Unlike larger SPIONs that primarily function as T2/T2*negative contrast agents,usSPIONs with core diameters below 5 nm can effectively shorten T1 relaxation times,producing bright signals in T1‐weighted images.This distinct behavior stems from their unique magnetic properties,including single‐domain configurations,surface spin canting,and rapid Néel relaxation dynamics,which are particularly enhanced at low magnetic field strengths.The biocompatibility of iron oxide,efficient renal clearance pathways,and versatility for surface functionalization offer potential advantages over gadolinium‐based agents,especially regarding safety concerns related to nephrogenic systemic fibrosis and gadolinium deposition.These nanoparticles show particular promise for applications in lowfield MRI,vascular imaging,targeted molecular imaging,and theranostic platforms.Although challenges remain in optimizing synthesis methods for consistent production of monodisperse usSPIONs with tailored surface chemistry,ongoing research continues to advance their potential for clinical translation.This review explores the mechanisms,synthesis approaches,applications,and future perspectives of usSPIONs as positive contrast agents in MRI.
文摘The characte rization of MgFe_(2)O_(4)@CeO_(2) superparamagnetic nanocomposites was tho roughly investigated using powder X-ray diffraction(XRD),a vibrating sample magnetometer(VSM),scanning electron microscopy(SEM),dispersive X-ray analysis(EDX),elemental mapping(MAP),transmission electron microscopy(TEM),Brunauer-Emmett-Teller(BET) and UV-Vis diffuse reflectance spectroscopy(DRS)analyses.The photocatalytic activity of the synthesized samples was evaluated as a novel magnetic nanocatalyst for degrading Congo red(CR) dye in an aqueous solution under visible light at room conditions.The results demonstrate that the efficiency of photocatalytic degradation is higher than that of absorbance and photolysis.The degradation efficiency of photodegradation is 93% within 49% of total organic carbon removal performance.The prepared MgFe_(2)O_(4)@CeO_(2) magnetic nanocomposites(MNCs)can be easily recovered and recycled for five repeated cycles,demonstrating potential extensive efficiency in magnetic nanocomposites in wastewater and water treatment.The nanoscale morphology of MgFe_(2)O_(4)@CeO_(2) MNCs was characterized as spherical,with a size range of 35-40 nm,utilizing SEM and TEM techniques.The saturation magnetization(M_(s)) of the resulting nanocomposites was analyzed by VSM,revealing a value of 3.58 emu/g.Furthermore,the surface area was determined to be 27.194 m^(2)/g using BET analysis,and the band gap was identified as 2.85 eV through DRS analysis.
基金supported by the China Science and Technology Innovation 2030-Major Project(2022ZD0211700)the Major Program of the National Natural Science Foundation of China(62394312)+2 种基金the National Natural Science Foundation of China(82471536)the Wenzhou Science and Technology Projects(ZY2023006,2024R2002)Oujiang Laboratory(OJQD2022002).
文摘Magnetic stimulation has made significant strides in the treatment of psychiatric disorders.Nonetheless,current magnetic stimulation techniques lack the precision to accurately modulate specific nuclei and cannot realize deep brain magnetic stimulation.To address this,we utilized superparamagnetic iron oxide nanoparticles as mediators to achieve precise targeting and penetration.We investigated the effects of magnetic fields with varying frequencies on neuronal activity and compared the activation effects on neurons using a 10-Hz precise magneto-stimulation system(pMSS)with repetitive transcranial magnetic stimulation in mice.Oxytocin levels,dendritic morphology and density,and mouse behavior were measured before and after pMSS intervention.Our findings suggest that pMSS can activate oxytocinergic neurons,leading to upregulation of oxytocin secretion and neurite outgrowth.As a result,sociability was rapidly improved after a one-week pMSS treatment regimen.These results demonstrate a promising magneto-stimulation method for regulating neuronal activity in deep brain nuclei and provide a promising therapeutic approach for autism spectrum disorder.
基金supported by the National Natural Science Foundation of China(Grant Nos.82073308 and 82104089)。
文摘Glioblastoma multiforme(GBM)is a highly aggressive and lethal brain tumor with limited treatment options.To improve therapeutic efficacy,we developed a novel multifunctional nanoplatform,GM@P(T/S),comprised of polymeric nanoparticles coated with GBM cell membranes as well as co-loaded with temozolomide(TMZ)and superparamagnetic iron oxide(SPIO)nanoparticles.The successful preparation was confirmed in terms of particle size,morphology,stability,the in vitro drug release,and cellular uptake assays.We demonstrated that GM@P(T/S)exhibited the enhanced homotypic targeting,the prolonged blood circulation,and efficient bloodbrain barrier penetration in both in vitro and in vivo studies.The combination of TMZ and SPIO nanoparticles within GM@P(T/S)synergistically improved chemo-radiation therapy,leading to a reduced tumor growth,an increased survival,and minimal systemic toxicity in the orthotopic GBM mouse models.Our findings suggest that GM@P(T/S)holds a great promise as a targeted and efficient therapeutic strategy for GBM.
文摘The present paper covers a novel technology for the concentration of trace amounts of target oligonucleotide from the solution. This technique is based on a super-paramagnetic DNA nano-enricher constructed with a single strand DNA probe immobilized onto the surface of the super-paramagnetic nanoparticles prepared by using the water-in-oil microemulsion technique, employing silica as the shell and iron oxide as the core of the super-paramagnetic nanoparticles. The silica coated magnetic nanoparticles are (40±4) nm in size. And the magnetic nanoparticle is super-paramagnetic. Biotin labeled ssDNA(Biotin-5-(A)10-GAT-TCA-CGA-GGC-CCT-AGT-CG-3) was immobilized on the surface of silica coated magnetic nanoparticles. The complementary ssDNA could be enriched effectively and the characteristics of the enriched ssDNA have not changed, which will provide a novel technique and measurement for gene transfection, mutation detection, gene diagnosis, gene therapy and so on.
