In neuroscience research,neuronal models are crucial tools for elucidating the molecular and cellular processes involved in the disorders of the nervous system.Facilitating easily and reproducibly executable studies,i...In neuroscience research,neuronal models are crucial tools for elucidating the molecular and cellular processes involved in the disorders of the nervous system.Facilitating easily and reproducibly executable studies,in vitro models,such as the SH-SY5Y cell line culture,help us explore the pathophysiological mechanisms of neurodegenerative diseases;they are also essential for the efficient screening of drugs for treating the diseases of the nervous system(Peng et al.,2021;Strother et al.,2021).展开更多
The effect of deposition temperature on the morphology and optoelectronic performance of Ge/Si QDs grown by magnetron sputtering under low Ge deposition(~4 nm)was investigated by atomic force microscopy,Raman spectros...The effect of deposition temperature on the morphology and optoelectronic performance of Ge/Si QDs grown by magnetron sputtering under low Ge deposition(~4 nm)was investigated by atomic force microscopy,Raman spectroscopy,and photoluminescence(PL)tests.The experimental results indicate that temperatures higher than 750℃effectively increase the crystallization rate and surface smoothness of the Si buffer layer,and temperatures higher than 600℃significantly enhance the migration ability of Ge atoms,thus increasing the probability of Ge atoms meeting and nucleating to form QDs on Si buffer layer,but an excessively high temperature will cause the QDs to undergo an Ostwald ripening process and thus develop into super large islands.In addition,some PL peaks were observed in samples containing small-sized,high-density Ge QDs,the photoelectric properties reflected by these peaks were in good agreement with the corresponding structural characteristics of the grown QDs.Our results demonstrate the viability of preparing high-quality QDs by magnetron sputtering at high deposition rate,and the temperature effect is expected to work in conjunction with other controllable factors to further regulate QD growth,which paves an effective way for the industrial production of QDs that can be used in future devices.展开更多
Neonatal hypoxic-ischemic encephalopathy is often associated with permanent cerebral palsy,neurosensory impairments,and cognitive deficits,and there is no effective treatment for complications related to hypoxic-ische...Neonatal hypoxic-ischemic encephalopathy is often associated with permanent cerebral palsy,neurosensory impairments,and cognitive deficits,and there is no effective treatment for complications related to hypoxic-ischemic encephalopathy.The therapeutic potential of human placental chorionic plate-derived mesenchymal stem cells for various diseases has been explored.However,the potential use of human placental chorionic plate-derived mesenchymal stem cells for the treatment of neonatal hypoxic-ischemic encephalopathy has not yet been investigated.In this study,we injected human placental chorionic plate-derived mesenchymal stem cells into the lateral ventricle of a neonatal hypoxic-ischemic encephalopathy rat model and observed significant improvements in both cognitive and motor function.Protein chip analysis showed that interleukin-3 expression was significantly elevated in neonatal hypoxic-ischemic encephalopathy model rats.Following transplantation of human placental chorionic plate-derived mesenchymal stem cells,interleukin-3 expression was downregulated.To further investigate the role of interleukin-3 in neonatal hypoxic-ischemic encephalopathy,we established an in vitro SH-SY5Y cell model of hypoxic-ischemic injury through oxygen-glucose deprivation and silenced interleukin-3 expression using small interfering RNA.We found that the activity and proliferation of SH-SY5Y cells subjected to oxygen-glucose deprivation were further suppressed by interleukin-3 knockdown.Furthermore,interleukin-3 knockout exacerbated neuronal damage and cognitive and motor function impairment in rat models of hypoxic-ischemic encephalopathy.The findings suggest that transplantation of hpcMSCs ameliorated behavioral impairments in a rat model of hypoxic-ischemic encephalopathy,and this effect was mediated by interleukin-3-dependent neurological function.展开更多
The single event effect(SEE) sensitivity of silicon–germanium heterojunction bipolar transistor(Si Ge HBT) irradiated by 100-Me V proton is investigated. The simulation results indicate that the most sensitive positi...The single event effect(SEE) sensitivity of silicon–germanium heterojunction bipolar transistor(Si Ge HBT) irradiated by 100-Me V proton is investigated. The simulation results indicate that the most sensitive position of the Si Ge HBT device is the emitter center, where the protons pass through the larger collector-substrate(CS) junction. Furthermore, in this work the experimental studies are also carried out by using 100-Me V proton. In order to consider the influence of temperature on SEE, both simulation and experiment are conducted at a temperature of 93 K. At a cryogenic temperature, the carrier mobility increases, which leads to higher transient current peaks, but the duration of the current decreases significantly.Notably, at the same proton flux, there is only one single event transient(SET) that occurs at 93 K. Thus, the radiation hard ability of the device increases at cryogenic temperatures. The simulation results are found to be qualitatively consistent with the experimental results of 100-Me V protons. To further evaluate the tolerance of the device, the influence of proton on Si Ge HBT after gamma-ray(^(60)Coγ) irradiation is investigated. As a result, as the cumulative dose increases, the introduction of traps results in a significant reduction in both the peak value and duration of the transient currents.展开更多
Introduction: Brain metastasis is common in relapsed neuroblastoma patients, but the characteristics of brain metastasis remain largely unknown. This study aimed to investigate the status of brain metastasis with neur...Introduction: Brain metastasis is common in relapsed neuroblastoma patients, but the characteristics of brain metastasis remain largely unknown. This study aimed to investigate the status of brain metastasis with neuroblastoma in South China.Methods: In this retrospective case?based study, 106 patients with stage 4 neuroblastoma from the Department of Pediatric Oncology in Sun Yat?sen University Cancer Center between January 2004 and May 2013 were included. The incidence, risk factors, and survival status of these patients were reviewed and analyzed.Results: Of the 106 patients, 11(10.4%) developed brain metastasis, accounting for 20.0% of 55 patients with relapse or progression. The age at initial diagnosis of the 11 patients ranged from 2 to 10 years(median 4 years), which was younger than that of the patients without brain metastasis(median 5 years, range 1–10 years, P = 0.073). The male to female ratio of the 11 patients was 8:3, which was not signiicantly diferent from that of the patients with?out brain metastasis(P = 0.86). Patients with brain metastasis had higher lactate dehydrogenase levels than those without brain metastasis, but the diferences were not signiicant(P initial diagnosis to the develo= 0.076). Eight patients died, and 3 patients survived. The median interval from thepment of brain metastasis was 18 months(range 6–32 months). The median survival was 4 months(range 1 day to 29 months) after the diagnosis of brain metastasis. The median interval from the manifestation of brain metastasis to death was 3 months(range 1 day to 11 months).Conclusions: High?risk factors for brain metastasis in cases of neuroblastoma include bone marrow involvement and a younger age at initial diagnosis. Nevertheless, multiple treatment modalities can improve disease?free survival.展开更多
基金supported in part by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior(Capes-Brazil),No.001(to MIG).
文摘In neuroscience research,neuronal models are crucial tools for elucidating the molecular and cellular processes involved in the disorders of the nervous system.Facilitating easily and reproducibly executable studies,in vitro models,such as the SH-SY5Y cell line culture,help us explore the pathophysiological mechanisms of neurodegenerative diseases;they are also essential for the efficient screening of drugs for treating the diseases of the nervous system(Peng et al.,2021;Strother et al.,2021).
基金Founded by the National Key Research and Development Program(No.2021YFB3802400)the National Natural Science Foundation of China(No.52161037)the Basic Research Project of Yunnan Province(No.202001AU070112)。
文摘The effect of deposition temperature on the morphology and optoelectronic performance of Ge/Si QDs grown by magnetron sputtering under low Ge deposition(~4 nm)was investigated by atomic force microscopy,Raman spectroscopy,and photoluminescence(PL)tests.The experimental results indicate that temperatures higher than 750℃effectively increase the crystallization rate and surface smoothness of the Si buffer layer,and temperatures higher than 600℃significantly enhance the migration ability of Ge atoms,thus increasing the probability of Ge atoms meeting and nucleating to form QDs on Si buffer layer,but an excessively high temperature will cause the QDs to undergo an Ostwald ripening process and thus develop into super large islands.In addition,some PL peaks were observed in samples containing small-sized,high-density Ge QDs,the photoelectric properties reflected by these peaks were in good agreement with the corresponding structural characteristics of the grown QDs.Our results demonstrate the viability of preparing high-quality QDs by magnetron sputtering at high deposition rate,and the temperature effect is expected to work in conjunction with other controllable factors to further regulate QD growth,which paves an effective way for the industrial production of QDs that can be used in future devices.
基金supported by the National Natural Science Foundation of China,No.82001604Guizhou Provincial Higher Education Science and Technology Innovation Team,No.[2023]072+1 种基金Guizhou Province Distinguished Young Scientific and Technological Talent Program,No.YQK[2023]040Guizhou Provincial Basic Research Program(Natural Science),No.ZK[2021]-368(all to LXiong),and Zunyi City Innovative Talent Team Training Plan,No.[2022]-2.
文摘Neonatal hypoxic-ischemic encephalopathy is often associated with permanent cerebral palsy,neurosensory impairments,and cognitive deficits,and there is no effective treatment for complications related to hypoxic-ischemic encephalopathy.The therapeutic potential of human placental chorionic plate-derived mesenchymal stem cells for various diseases has been explored.However,the potential use of human placental chorionic plate-derived mesenchymal stem cells for the treatment of neonatal hypoxic-ischemic encephalopathy has not yet been investigated.In this study,we injected human placental chorionic plate-derived mesenchymal stem cells into the lateral ventricle of a neonatal hypoxic-ischemic encephalopathy rat model and observed significant improvements in both cognitive and motor function.Protein chip analysis showed that interleukin-3 expression was significantly elevated in neonatal hypoxic-ischemic encephalopathy model rats.Following transplantation of human placental chorionic plate-derived mesenchymal stem cells,interleukin-3 expression was downregulated.To further investigate the role of interleukin-3 in neonatal hypoxic-ischemic encephalopathy,we established an in vitro SH-SY5Y cell model of hypoxic-ischemic injury through oxygen-glucose deprivation and silenced interleukin-3 expression using small interfering RNA.We found that the activity and proliferation of SH-SY5Y cells subjected to oxygen-glucose deprivation were further suppressed by interleukin-3 knockdown.Furthermore,interleukin-3 knockout exacerbated neuronal damage and cognitive and motor function impairment in rat models of hypoxic-ischemic encephalopathy.The findings suggest that transplantation of hpcMSCs ameliorated behavioral impairments in a rat model of hypoxic-ischemic encephalopathy,and this effect was mediated by interleukin-3-dependent neurological function.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.61574171,61704127,11875229,51872251,and 12027813)。
文摘The single event effect(SEE) sensitivity of silicon–germanium heterojunction bipolar transistor(Si Ge HBT) irradiated by 100-Me V proton is investigated. The simulation results indicate that the most sensitive position of the Si Ge HBT device is the emitter center, where the protons pass through the larger collector-substrate(CS) junction. Furthermore, in this work the experimental studies are also carried out by using 100-Me V proton. In order to consider the influence of temperature on SEE, both simulation and experiment are conducted at a temperature of 93 K. At a cryogenic temperature, the carrier mobility increases, which leads to higher transient current peaks, but the duration of the current decreases significantly.Notably, at the same proton flux, there is only one single event transient(SET) that occurs at 93 K. Thus, the radiation hard ability of the device increases at cryogenic temperatures. The simulation results are found to be qualitatively consistent with the experimental results of 100-Me V protons. To further evaluate the tolerance of the device, the influence of proton on Si Ge HBT after gamma-ray(^(60)Coγ) irradiation is investigated. As a result, as the cumulative dose increases, the introduction of traps results in a significant reduction in both the peak value and duration of the transient currents.
文摘Introduction: Brain metastasis is common in relapsed neuroblastoma patients, but the characteristics of brain metastasis remain largely unknown. This study aimed to investigate the status of brain metastasis with neuroblastoma in South China.Methods: In this retrospective case?based study, 106 patients with stage 4 neuroblastoma from the Department of Pediatric Oncology in Sun Yat?sen University Cancer Center between January 2004 and May 2013 were included. The incidence, risk factors, and survival status of these patients were reviewed and analyzed.Results: Of the 106 patients, 11(10.4%) developed brain metastasis, accounting for 20.0% of 55 patients with relapse or progression. The age at initial diagnosis of the 11 patients ranged from 2 to 10 years(median 4 years), which was younger than that of the patients without brain metastasis(median 5 years, range 1–10 years, P = 0.073). The male to female ratio of the 11 patients was 8:3, which was not signiicantly diferent from that of the patients with?out brain metastasis(P = 0.86). Patients with brain metastasis had higher lactate dehydrogenase levels than those without brain metastasis, but the diferences were not signiicant(P initial diagnosis to the develo= 0.076). Eight patients died, and 3 patients survived. The median interval from thepment of brain metastasis was 18 months(range 6–32 months). The median survival was 4 months(range 1 day to 29 months) after the diagnosis of brain metastasis. The median interval from the manifestation of brain metastasis to death was 3 months(range 1 day to 11 months).Conclusions: High?risk factors for brain metastasis in cases of neuroblastoma include bone marrow involvement and a younger age at initial diagnosis. Nevertheless, multiple treatment modalities can improve disease?free survival.
