Our previous study showed that systemic administration of the traditional Chinese medicine Epimedium extract promotes peripheral nerve regeneration. Here, we sought to explore the ther- apeutic effects of local admini...Our previous study showed that systemic administration of the traditional Chinese medicine Epimedium extract promotes peripheral nerve regeneration. Here, we sought to explore the ther- apeutic effects of local administration of icariin, a major component of Epimedium extract, on peripheral nerve regeneration. A poly（lactic-co-glycolic acid） biological conduit sleeve was used to bridge a 5 mm right sciatic nerve defect in rats, and physiological saline, nerve growth factor, icariin suspension, or nerve growth factor-releasing microsphere suspension was injected into the defect. Twelve weeks later, sciatic nerve conduction velocity and the number of myelinated fibers were notably greater in the rats treated with icariin suspension or nerve growth factor-releasing microspheres than those that had received nerve growth factor or physiological saline. The effects of icariin suspension were similar to those of nerve growth factor-releasing microspheres. These data suggest that icariin acts as a nerve growth factor-releasing agent, and indicate that local ap- plication of icariin after spinal injury can promote peripheral nerve regeneration.展开更多
We examined the restorative effect of modified biodegradable chitin conduits in combination with bone marrow mesenchymal stem cell transplantation after right spinal cord hemisection injury. Immunohistochemical staini...We examined the restorative effect of modified biodegradable chitin conduits in combination with bone marrow mesenchymal stem cell transplantation after right spinal cord hemisection injury. Immunohistochemical staining revealed that biological conduit sleeve bridging reduced glial scar formation and spinal muscular atrophy after spinal cord hemisection. Bone marrow mesenchymal stem cells survived and proliferated after transplantation in vivo, and differentiated into cells double-positive for S100 （Schwann cell marker） and glial fibrillary acidic protein （glial cell marker） at 8 weeks. Retrograde tracing showed that more nerve fibers had grown through the injured spinal cord at 14 weeks after combination therapy than either treatment alone. Our findings indicate that a biological conduit combined with bone marrow mesenchymal stem cell transplantation effectively prevented scar formation and provided a favorable local microenvi- ronment for the proliferation, migration and differentiation of bone marrow mesenchymal stem cells in the spinal cord, thus promoting restoration following spinal cord hemisection injury.展开更多
Electrical stimulation has been shown to accelerate and enhance nerve regeneration in sensory and motor neurons after injury, but there is little evidence that focuses on the varying degrees of fibrosis in the delayed...Electrical stimulation has been shown to accelerate and enhance nerve regeneration in sensory and motor neurons after injury, but there is little evidence that focuses on the varying degrees of fibrosis in the delayed repair of peripheral nerve tissue. In this study, a rat model of sciatic nerve transec- tion injury was repaired with a biodegradable conduit at 1 day, 1 week, 1 month and 2 months after injury, when the rats were divided into two subgroups. In the experimental group, rats were treated with electrical stimuli of frequency of 20 Hz, pulse width 100 ms and direct current voltage of 3 V; while rats in the control group received no electrical stimulation after the conduit operation. His- tological results showed that stained collagen fibers comprised less than 20% of the total operated area in the two groups after delayed repair at both 1 day and 1 week but after longer delays, the collagen fiber area increased with the time after injury. Immunohistochemical staining revealed that the expression level of transforming growth factor ~ （an indicator of tissue fibrosis） decreased at both 1 day and 1 week after delayed repair but increased at both 1 and 2 months after delayed repair. These findings indicate that if the biodegradable conduit repair combined with electrical stimulation is delayed, it results in a poor outcome following sciatic nerve injury. One month after injury, tissue degeneration and distal fibrosis are apparent and are probably the main reason why electrical stimulation fails to promote nerve regeneration after delayed repair.展开更多
Neutrophil peptide 1 belongs to a family of peptides involved in innate immunity. Continuous intramuscular injection of neutrophil peptide 1 can promote the regeneration of peripheral nerves, but clinical application ...Neutrophil peptide 1 belongs to a family of peptides involved in innate immunity. Continuous intramuscular injection of neutrophil peptide 1 can promote the regeneration of peripheral nerves, but clinical application in this manner is not convenient. To this end, the effects of a single intraoperative administration of neutrophil peptide 1 on peripheral nerve regeneration were experimentally observed. A rat model of sciatic nerve crush injury was established using the clamp method. After model establishment, a normal saline group and a neutrophil peptide 1 group were injected with a single dose of normal saline or 10 μg/mL neutrophil peptide 1, respectively. A sham group, without sciatic nerve crush was also prepared as a control. Sciatic nerve function tests, neuroelectrophysiological tests, and hematoxylin-eosin staining showed that the nerve conduction velocity, sciatic functional index, and tibialis anterior muscle fiber cross-sectional area were better in the neutrophil peptide 1 group than in the normal saline group at 4 weeks after surgery. At 4 and 8 weeks after surgery, there were no differences in the wet weight of the tibialis anterior muscle between the neutrophil peptide 1 and saline groups. Histological staining of the sciatic nerve showed no significant differences in the number of myelinated nerve fibers or the axon cross-sectional area between the neutrophil peptide 1 and normal saline groups. The above data confirmed that a single dose of neutrophil peptide 1 during surgery can promote the recovery of neurological function 4 weeks after sciatic nerve injury. All the experiments were approved by the Medical Ethics Committee of Peking University People's Hospital, China(approval No. 2015-50) on December 9, 2015.展开更多
The development of high-performance electrocatalysts holds the decisive key to the electrochemical CO2 reduction toward value-added products. Formic acid or formate is a desirable reduction product, but its selective ...The development of high-performance electrocatalysts holds the decisive key to the electrochemical CO2 reduction toward value-added products. Formic acid or formate is a desirable reduction product, but its selective production is often challenging. Tin based-materials have attracted great attention for formate production, and yet their performances are far from satisfactory. In this study, we reported the preparation of SnO2 nanoclusters from the controlled self-polymerization of dopamine together with SnO32-, followed by the mild-temperature calcination. The final product consisted of large primary particles that were further made of small secondary SnO2 nanocrystals. When evaluated as the electrocatalyst for CO2 reduction in 0.5 M NaHCO3, our material exhibited impressive activity, selectivity and stability for the selective CO2 reduction to formate. A peak formate Faradaic efficiency of^73% and large partial current density of 16.3 mA/cm2 was achieved at -0.92 V versus reversible hydrogen electrode.展开更多
A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell cultu...A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell culture, 57 Influenza A Pandemic （H1N1） viruses were isolated and submitted for whole genome sequencing. A total of 39 HA sequences, 52 NA sequences, 36 PB2 sequences, 31 PB1 sequences, 40 PA sequences, 48 NP sequences, 51 MP sequences and 36 NS sequences were obtained, including 20 whole genome sequences. Sequence comparison revealed they shared a high degree of homology （96%-99%） with known epidemic strains （A/Califomia/04/2009（H1N1）. Phylogenetic analysis showed that although the sequences were highly conserved, they clustered into a small number of groups with only a few distinct strains. Site analysis revealed three substitutions at loop 220 （221-228） of the HA receptor binding site in the 39 HA sequences： A/Hubei/86/2009 PKVRDQEG→PKVRDQEA, A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER, A/Hubei/75/2009 PKVRDQEG→PKVRDQGG, the A/Hubei/75/2009 was isolated from an acute case, while the other two were from patients with mild symptoms. Other key sites such as 119, 274, 292 and 294 amino acids of NA protein,627 of PB2 protein were conserved. Meanwhile, all the M2 protein sequences possessed the Ser32Asn mutation, suggesting that these viruses were resistant to adamantanes. Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.展开更多
Objective To investigate the clinical features and treatment of placenta previa complicated with previous caesarean section. Methods The clinical data of 29 patients with placenta previa complicated with a previous ca...Objective To investigate the clinical features and treatment of placenta previa complicated with previous caesarean section. Methods The clinical data of 29 patients with placenta previa complicated with a previous caesarean section (RCS group) admitted in Peking Union Medical College Hospital during a period from 2003 to 2011 were retrospectively reviewed and compared with those of 243 patients with placenta previa without a previous caesarean section (FCS group) during the same period. Results There was no difference in the mean age (28.9±3.6 vs. 28.1±4.5 years) and the average gravidity (2.35±1.48 vs. 2.21±1.53) between RCS group and FCS group (all P>0.05). The RCS group had more preterm births (24.1% vs. 13.2%), complete placenta previa (55.2% vs. 4.9%), placenta accreta (34.5% vs. 2.5%), more blood loss during caesarean section (1412±602 vs. 648±265 mL), blood transfusion (51.7% vs. 4.9%), disseminated intravascular coagulation (13.8% vs. 2.1%), and obstetric hysterectomy (13.8% vs. 0.8%) than the FCS group (all P<0.05). The preterm infant rate (30.0% vs. 13.0%), neonatal asphyxia rate (10.0% vs. 4.9%), and perinatal mortality rate (6.7% vs. 0.4%) of the RCS group were higher than those of the FCS group (all P<0.05). Conclusions More patients had complete placenta previa and placenta accreta, postpartum hemorrhage, transfusion, uterine packing, obstetric hysterectomy, and perinatal morbidity in the placenta previa patients with previous caesarean section. The patient should be informed of the risk and unnecessary first cesarean sections should be avoided.展开更多
Multiple-bud regeneration, i.e., multiple amplification, has been shown to exist in peripheral nerve regeneration. Multiple buds grow towards the distal nerve stump during proximal nerve fiber regeneration. Our previo...Multiple-bud regeneration, i.e., multiple amplification, has been shown to exist in peripheral nerve regeneration. Multiple buds grow towards the distal nerve stump during proximal nerve fiber regeneration. Our previous studies have verified the limit and validity of multiple ampli- fication of peripheral nerve regeneration using small gap sleeve bridging of small donor nerves to repair large receptor nerves in rodents. The present study sought to observe multiple ampli- fication of myelinated nerve fiber regeneration in the primate peripheral nerve. Rhesus monkey models of distal ulnar nerve defects were established and repaired using muscular branches of the right forearm pronator teres. Proximal muscular branches of the pronator teres were su- tured into the distal ulnar nerve using the small gap sleeve bridging method. At 6 months after suture, two-finger flexion and mild wrist flexion were restored in the ulnar-sided injured limbs of rhesus monkey. Neurophysiological examination showed that motor nerve conduction veloc- ity reached 22.63 _＋ 6.34 m/s on the affected side of rhesus monkey. Osmium tetroxide staining demonstrated that the number of myelinated nerve fibers was 1,657 ＋ 652 in the branches of pronator teres of donor, and 2,661 ~ 843 in the repaired ulnar nerve. The rate of multiple amplification of regenerating myelinated nerve fibers was 1.61. These data showed that when muscular branches of the pronator teres were used to repair ulnar nerve in primates, effective regeneration was observed in regenerating nerve fibers, and functions of the injured ulnar nerve were restored to a certain extent. Moreover, multiple amplification was subsequently detected in ulnar nerve axons.展开更多
In China, there are approximately 20 million people suffering from peripheral nerve injury and this number is increasing at a rate of 2 million per year. These patients cannot live or work independently and are a heav...In China, there are approximately 20 million people suffering from peripheral nerve injury and this number is increasing at a rate of 2 million per year. These patients cannot live or work independently and are a heavy responsibility on both family and society because of extreme disability and dysfunction caused by peripheral nerve injury （PNI）. Thus, repair of PNI has become a major public health issue in China.展开更多
Our previous studies have confirmed that during nerve transposition repair to injured peripheral nerves, the regenerated nerve fibers of motor neurons in the anterior horn of the spinal cord can effectively repair dis...Our previous studies have confirmed that during nerve transposition repair to injured peripheral nerves, the regenerated nerve fibers of motor neurons in the anterior horn of the spinal cord can effectively repair distal nerve and target muscle tissue and restore muscle motor function. To observe the effect of nerve regeneration and motor function recovery after several types of nerve transposition for median nerve defect(2 mm), 30 Sprague-Dawley rats were randomly divided into sham operation group, epineurial neurorrhaphy group, musculocutaneous nerve transposition group, medial pectoral nerve transposition group, and radial nerve muscular branch transposition group. Three months after nerve repair, the wrist flexion test was used to evaluate the recovery of wrist flexion after regeneration of median nerve in the affected limbs of rats. The number of myelinated nerve fibers, the thickness of myelin sheath, the diameter of axons and the cross-sectional area of axons in the proximal and distal segments of the repaired nerves were measured by osmic acid staining. The ratio of newly produced distal myelinated nerve fibers to the number of proximal myelinated nerve fibers was calculated. Wet weights of the flexor digitorum superficialis muscles were measured. Muscle fiber morphology was detected using hematoxylin-eosin staining. The cross-sectional area of muscle fibers was calculated to assess the recovery of muscles. Results showed that wrist flexion function was restored, and the nerve grew into the distal effector in all three nerve transposition groups and the epineurial neurorrhaphy group. There were differences in the number of myelinated nerve fibers in each group. The magnification of proximal to distal nerves was 1.80, 3.00, 2.50, and 3.12 in epineurial neurorrhaphy group, musculocutaneous nerve transposition group, medial pectoral nerve transposition group, and radial nerve muscular branch transposition group, respectively. Nevertheless, axon diameters of new nerve fibers, cross-sectional areas of axons, thicknesses of myelin sheath, wet weights of flexor digitorum superficialis muscle and cross-sectional areas of muscle fibers of all three groups of donor nerves from different anterior horn motor neurons after nerve transposition were similar to those in the epineurial neurorrhaphy group. Our findings indicate that donor nerve translocation from different anterior horn motor neurons can effectively repair the target organs innervated by the median nerve. The corresponding spinal anterior horn motor neurons obtain functional reinnervation and achieve some degree of motor function in the affected limbs.展开更多
Complex pathological changes occur during the development of spinal cord injury(SCI),and determining the underlying molecular events that occur during SCI is necessary for the development of promising molecular target...Complex pathological changes occur during the development of spinal cord injury(SCI),and determining the underlying molecular events that occur during SCI is necessary for the development of promising molecular targets and therapeutic strategies.This study was designed to explore differentially expressed genes(DEGs)associated with the acute and chronic stages of SCI using bioinformatics analysis.Gene expression profiles(GSE45006,GSE93249,and GSE45550)were downloaded from the Gene Expression Omnibus database.SCI-associated DEGs from rat samples were identified,and Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed.In addition,a protein-protein interaction network was constructed.Approximately 66 DEGs were identified in GSE45550 between 3–14 days after SCI,whereas 2418 DEGs were identified in GSE450061–56 days after SCI.Moreover,1263,195,and 75 overlapping DEGs were identified between these two expression profiles,3,7/8,and 14 days after SCI,respectively.Additionally,16 overlapping DEGs were obtained in GSE450061–14 days after SCI,including Pank1,Hn1,Tmem150c,Rgd1309676,Lpl,Mdh1,Nnt,Loc100912219,Large1,Baiap2,Slc24a2,Fundc2,Mrps14,Slc16a7,Obfc1,and Alpk3.Importantly,3882 overlapping DEGs were identified in GSE932491–6 months after SCI,including 3316 protein-coding genes and 567 long non-coding RNA genes.A comparative analysis between GSE93249 and GSE45006 resulted in the enrichment of 1135 overlapping DEGs.The significant functions of these 1135 genes were correlated with the response to the immune effector process,the innate immune response,and cytokine production.Moreover,the biological processes and KEGG pathways of the overlapping DEGs were significantly enriched in immune system-related pathways,osteoclast differentiation,the nuclear factor-κB signaling pathway,and the chemokine signaling pathway.Finally,an analysis of the overlapping DEGs associated with both acute and chronic SCI,assessed using the expression profiles GSE93249 and GSE45006,identified four overlapping DEGs:Slc16a7,Alpk3,Lpl and Nnt.These findings may be useful for revealing the biological processes associated with SCI and the development of targeted intervention strategies.展开更多
To understand the molecular characteristics of China human rabies vaccine strains, we report the full-length genome of the aG strain and present a comprehensive analysis of this strain and almost all available lyssavi...To understand the molecular characteristics of China human rabies vaccine strains, we report the full-length genome of the aG strain and present a comprehensive analysis of this strain and almost all available lyssavirus genomes （58 strains） from GenBank （as of Jan 6, 2011）. It is generally considered that the G protein plays a predominant role in determining the pathogenicity of the virus, to this end we predicted the tertiary structure of the G protein of aG strain, CTN 181 strain and wild type strain HN 10 based on the crystal structure of Vesicular stomatitis virus （VSV） G. The predicted RABV G structure has a similar topology to VSV G and the ectodomain can be divided into 4 distinct domains DI - DIV. By mapping the characterized mutations to this structure between China vaccine strains and their close street strains, we speculate that the G303（P-H） mutations of CTN181 and HN10 causing D II 3D change may be associated with the attenuated virulence in both strains. Specifically, the two signature mutations （G165P and G231P） in the aG strain are withinβsheets, suggesting that both sites are of structural importance.展开更多
The purpose of this study was to investigate the effect of four fluorescent dyes, True Blue（TB）, Fluoro-Gold（FG）, Fluoro-Ruby（FR）, and 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate（Di I...The purpose of this study was to investigate the effect of four fluorescent dyes, True Blue（TB）, Fluoro-Gold（FG）, Fluoro-Ruby（FR）, and 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate（Di I）, in retrograde tracing of rat spinal motor neurons. We transected the muscle branch of the rat femoral nerve and applied each tracer to the proximal stump in single labeling experiments, or combinations of tracers（FG-Di I and TB-Di I） in double labeling experiments. In the single labeling experiments, significantly fewer labeled motor neurons were observed after FR labeling than after TB, FG, or Di I, 3 days after tracer application. By 1 week, there were no significant differences in the number of labeled neurons between the four groups. In the double-labeling experiment, the number of double-labeled neurons in the FG-Di I group was not significantly different from that in the TB-Di I group 1 week after tracer application. Our findings indicate that TB, FG, and Di I have similar labeling efficacies in the retrograde labeling of spinal motor neurons in the rat femoral nerve when used alone. Furthermore, combinations of Di I and TB or FG are similarly effective. Therefore, of the dyes studied, TB, FG and Di I, and combinations of Di I with TB or FG, are the most suitable for retrograde labeling studies of motor neurons in the rat femoral nerve.展开更多
Dear Editor, We report the results of evolutionary history estimation of the lyssaviruses based on an analysis of the Glycoprotein (G) sequences gene using the BEAST software package. The most recent common ancestor (...Dear Editor, We report the results of evolutionary history estimation of the lyssaviruses based on an analysis of the Glycoprotein (G) sequences gene using the BEAST software package. The most recent common ancestor (TMRCA) of all the lyssavirus strains was estimated to be approximately 5030 years (95% HPD 3988-6069 years), and there was a significant spread of the rabies virus throughout the world range in the last 200 years, consistent with significant time points in development and migration of human civilizations.展开更多
Multiple regeneration of axonal buds has been shown to exist during the repair of peripheral nerve injury, which confirms a certain repair potential of the injured peripheral nerve. Therefore, a systematic nerve trans...Multiple regeneration of axonal buds has been shown to exist during the repair of peripheral nerve injury, which confirms a certain repair potential of the injured peripheral nerve. Therefore, a systematic nerve transposition repair technique has been proposed to treat severe peripheral nerve injury. During nerve transposition repair, the regenerated nerve fibers of motor neurons in the anterior horn of the spinal cord can effectively grow into the repaired distal nerve and target muscle tissues, which is conducive to the recovery of motor function. The aim of this study was to explore regeneration and nerve functional recovery after repairing a long-segment peripheral nerve defect by transposition of different donor nerves. A long-segment(2 mm) ulnar nerve defect in Sprague-Dawley rats was repaired by transposition of the musculocutaneous nerve, medial pectoral nerve, muscular branches of the radial nerve and anterior interosseous nerve(pronator quadratus muscle branch). In situ repair of the ulnar nerve was considered as a control. Three months later, wrist flexion function, nerve regeneration and innervation muscle recovery in rats were assessed using neuroelectrophysiological testing, osmic acid staining and hematoxylin-eosin staining, respectively. Our findings indicate that repair of a long-segment ulnar nerve defect with different donor nerve transpositions can reinnervate axonal function of motor neurons in the anterior horn of spinal cord and restore the function of affected limbs to a certain extent.展开更多
Hyperlipidemia(HLP)is a long-known risk factor for a series of cardiovascular and cerebrovascular diseases,such as atherosclerosis,coronary heart disease,hypertension and so on.With its increasing incidence,the preven...Hyperlipidemia(HLP)is a long-known risk factor for a series of cardiovascular and cerebrovascular diseases,such as atherosclerosis,coronary heart disease,hypertension and so on.With its increasing incidence,the prevention and treatment of HLP has also become an important research topic around the world.Traditional Chinese medicine(TCM)has been used to treat HLP for a long time with its better therapeutic efficacy,less side effects and wider indications compared with western medicine.In this review,we summarized the pathogenesis of HLP,the research situation of disease-related targets,and the treatment progress of TCM by conducting literature research and sorting out relevant information,in order to provide reference for further research of HLP and prevent the occurrence of cardiovascular and cerebrovascular diseases.展开更多
Dear Editor,Nucleotide and protein sequences of isolates collectedfrom infected populations can be useful for determiningthe threats,such as host adaptation,which are associatedwith the emergence of new lineages.March...Dear Editor,Nucleotide and protein sequences of isolates collectedfrom infected populations can be useful for determiningthe threats,such as host adaptation,which are associatedwith the emergence of new lineages.March 2013 saw thefirst reports of a new H7N9 lineage in Shanghai,Chinathat saw a gradual increase in the number of cases;but,by 17th May 2013,four Chinese provinces had展开更多
China's dynamic zero-COVID policy has effectively curbed the spread of SARS-CoV-2,while inadvertently creating immunity gaps within its population.Subsequent surges in COVID-19 cases linked to various SARS-CoV-2 l...China's dynamic zero-COVID policy has effectively curbed the spread of SARS-CoV-2,while inadvertently creating immunity gaps within its population.Subsequent surges in COVID-19 cases linked to various SARS-CoV-2 lineages post-policy termination necessitate a thorough investigation into the epidemiological landscape.This study addresses this issue by analyzing a comprehensive dataset of 39,456 high-quality genomes collected nationwide over an 11-month period since policy termination.Through lineage assignment,phylogenetic analysis,pandemic pattern comparison,phylodynamic reconstruction,and recombination detection,we found that China's postepidemic period could be divided into three stages,along with dynamic changes in dominant lineages.Geographical clustering of similar lineages implies the importance of cross-border cooperation among neighboring regions.Compared to the USA,UK,and Japan,China exhibits unique trajectories of lineage epidemics,characterized by initial lagging followed by subsequent advancement,indicating the potential influence of diverse prevention and control policies on lineage epidemic patterns.Hong Kong,Shanghai,and Hubei emerge as pivotal nodes in the nationwide spread,marking a shift in the transmission center from east to central regions of China.Although China hasn't experienced significant variant emergence,the detection and validation of the novel recombination event,XCN lineage,underscore the ongoing virus evolution.Overall,this study systematically analyzes the spatiotemporal transmission of SARS-CoV-2 virus in China since the termination of the dynamic zeroCOVID policy,offering valuable insights for regional surveillance and evidence-based public health policymaking.展开更多
The authors reply:We deeply appreciated your interest in our research.In our study,the conclusion that femoral head necrosis induced by large doses of steroid pulse therapy in SARS patients was partially reversible wa...The authors reply:We deeply appreciated your interest in our research.In our study,the conclusion that femoral head necrosis induced by large doses of steroid pulse therapy in SARS patients was partially reversible was based on the results of the volume of femoral head necrosis on MRI combined with the ARCO stage.The volume of osteonecrosis decreased significantly from 2003(38.83%±21.01%)to 2005(30.38%±20.23%)(P=0.0002),then declined slowly from 2005 to 2013(28.99%±20.59%)and plateaued in 2018(25.52%±15.51%).The ARCO stages of 17 limbs in ten patients stabilized or improved during follow-up,while the stages of six limbs in four patients reflected deterioration.展开更多
基金supported by grants from the National Program on Key Basic Research Project of China(973 Program),No.2014CB542200the National Natural Science Foundation of China,No.31271284,81171146,31100860+1 种基金the Natural Science Foundation of Beijing of China,No.7142164Program for Innovative Research Team in University of Ministry of Education of China,No.IRT1201
文摘Our previous study showed that systemic administration of the traditional Chinese medicine Epimedium extract promotes peripheral nerve regeneration. Here, we sought to explore the ther- apeutic effects of local administration of icariin, a major component of Epimedium extract, on peripheral nerve regeneration. A poly（lactic-co-glycolic acid） biological conduit sleeve was used to bridge a 5 mm right sciatic nerve defect in rats, and physiological saline, nerve growth factor, icariin suspension, or nerve growth factor-releasing microsphere suspension was injected into the defect. Twelve weeks later, sciatic nerve conduction velocity and the number of myelinated fibers were notably greater in the rats treated with icariin suspension or nerve growth factor-releasing microspheres than those that had received nerve growth factor or physiological saline. The effects of icariin suspension were similar to those of nerve growth factor-releasing microspheres. These data suggest that icariin acts as a nerve growth factor-releasing agent, and indicate that local ap- plication of icariin after spinal injury can promote peripheral nerve regeneration.
基金supported by grants from the National Program on Key Basic Research Project of China(973 Program),No.2014CB542201Program for Innovative Research Team in University of Ministry of Education of China,No.IRT1201+2 种基金the National Natural Science Foundation of China,No.31271284,31171150,81171146,30971526,31100860,31040043Program for New Century Excellent Talents in University of Ministry of Education of China,No.BMU20110270the Natural Science Foundation of Beijing of China,No.7142164
文摘We examined the restorative effect of modified biodegradable chitin conduits in combination with bone marrow mesenchymal stem cell transplantation after right spinal cord hemisection injury. Immunohistochemical staining revealed that biological conduit sleeve bridging reduced glial scar formation and spinal muscular atrophy after spinal cord hemisection. Bone marrow mesenchymal stem cells survived and proliferated after transplantation in vivo, and differentiated into cells double-positive for S100 （Schwann cell marker） and glial fibrillary acidic protein （glial cell marker） at 8 weeks. Retrograde tracing showed that more nerve fibers had grown through the injured spinal cord at 14 weeks after combination therapy than either treatment alone. Our findings indicate that a biological conduit combined with bone marrow mesenchymal stem cell transplantation effectively prevented scar formation and provided a favorable local microenvi- ronment for the proliferation, migration and differentiation of bone marrow mesenchymal stem cells in the spinal cord, thus promoting restoration following spinal cord hemisection injury.
基金supported by grants from the National Program on Key Basic Research Project of China(973 Program),No.2014CB542206Program for Innovative Research Team in University of Ministry of Education of China,No.IRT1201+2 种基金the National Natural Science Foundation of China,No.31271284,31171150,81171146,30971526,31100860,31040043,31440055the Natural Science Foundation of Beijing of China,No.7142164Program for New Century Excellent Talents in University of Ministry of Education of China,No.BMU20110270
文摘Electrical stimulation has been shown to accelerate and enhance nerve regeneration in sensory and motor neurons after injury, but there is little evidence that focuses on the varying degrees of fibrosis in the delayed repair of peripheral nerve tissue. In this study, a rat model of sciatic nerve transec- tion injury was repaired with a biodegradable conduit at 1 day, 1 week, 1 month and 2 months after injury, when the rats were divided into two subgroups. In the experimental group, rats were treated with electrical stimuli of frequency of 20 Hz, pulse width 100 ms and direct current voltage of 3 V; while rats in the control group received no electrical stimulation after the conduit operation. His- tological results showed that stained collagen fibers comprised less than 20% of the total operated area in the two groups after delayed repair at both 1 day and 1 week but after longer delays, the collagen fiber area increased with the time after injury. Immunohistochemical staining revealed that the expression level of transforming growth factor ~ （an indicator of tissue fibrosis） decreased at both 1 day and 1 week after delayed repair but increased at both 1 and 2 months after delayed repair. These findings indicate that if the biodegradable conduit repair combined with electrical stimulation is delayed, it results in a poor outcome following sciatic nerve injury. One month after injury, tissue degeneration and distal fibrosis are apparent and are probably the main reason why electrical stimulation fails to promote nerve regeneration after delayed repair.
基金funded by the National Natural Science Foundation of China,No.31571236(to YHK)the Key Laboratory of Trauma and Neural Regeneration(Peking University),Ministry of Education,China,No.BMU2019XY007-01(to YHK)+1 种基金the Ministry of Education Innovation Program of China,No.IRT_16R01(to YHK)the Research and Development Funds of Peking University People’s Hospital,China,Nos.RDH2017-01(to YHK),RDY2018-09(to HL)。
文摘Neutrophil peptide 1 belongs to a family of peptides involved in innate immunity. Continuous intramuscular injection of neutrophil peptide 1 can promote the regeneration of peripheral nerves, but clinical application in this manner is not convenient. To this end, the effects of a single intraoperative administration of neutrophil peptide 1 on peripheral nerve regeneration were experimentally observed. A rat model of sciatic nerve crush injury was established using the clamp method. After model establishment, a normal saline group and a neutrophil peptide 1 group were injected with a single dose of normal saline or 10 μg/mL neutrophil peptide 1, respectively. A sham group, without sciatic nerve crush was also prepared as a control. Sciatic nerve function tests, neuroelectrophysiological tests, and hematoxylin-eosin staining showed that the nerve conduction velocity, sciatic functional index, and tibialis anterior muscle fiber cross-sectional area were better in the neutrophil peptide 1 group than in the normal saline group at 4 weeks after surgery. At 4 and 8 weeks after surgery, there were no differences in the wet weight of the tibialis anterior muscle between the neutrophil peptide 1 and saline groups. Histological staining of the sciatic nerve showed no significant differences in the number of myelinated nerve fibers or the axon cross-sectional area between the neutrophil peptide 1 and normal saline groups. The above data confirmed that a single dose of neutrophil peptide 1 during surgery can promote the recovery of neurological function 4 weeks after sciatic nerve injury. All the experiments were approved by the Medical Ethics Committee of Peking University People's Hospital, China(approval No. 2015-50) on December 9, 2015.
基金supports from the National Natural Science Foundation of China (51472173 and 51522208)the Natural Science Foundation of Jiangsu Province (SBK2015010320)the Priority Academic Program Development of Jiangsu Higher Education Institutions and Collaborative Innovation Center of Suzhou Nano Science and Technology
文摘The development of high-performance electrocatalysts holds the decisive key to the electrochemical CO2 reduction toward value-added products. Formic acid or formate is a desirable reduction product, but its selective production is often challenging. Tin based-materials have attracted great attention for formate production, and yet their performances are far from satisfactory. In this study, we reported the preparation of SnO2 nanoclusters from the controlled self-polymerization of dopamine together with SnO32-, followed by the mild-temperature calcination. The final product consisted of large primary particles that were further made of small secondary SnO2 nanocrystals. When evaluated as the electrocatalyst for CO2 reduction in 0.5 M NaHCO3, our material exhibited impressive activity, selectivity and stability for the selective CO2 reduction to formate. A peak formate Faradaic efficiency of^73% and large partial current density of 16.3 mA/cm2 was achieved at -0.92 V versus reversible hydrogen electrode.
基金The Ministry of Science and Technology of China (2010CB534005,2007FY210700, 2009ZX10004109)the National Natural Science Foundation of China (30970024,30900060)+2 种基金The National R&D Infrastructure and Facility Development Program of China under Grant No. BSDN2009-10 &18The Chinese Academy of Sciences (KSCX2-YW- N-065, KSCX2-YW-R-157, 158 and 159 INFO-115-C01-SDB3-01, INFO-115-C01-SDB4-21, IN-FO-115-D02, IN-FO- 115-C01-SDB2-02)
文摘A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell culture, 57 Influenza A Pandemic （H1N1） viruses were isolated and submitted for whole genome sequencing. A total of 39 HA sequences, 52 NA sequences, 36 PB2 sequences, 31 PB1 sequences, 40 PA sequences, 48 NP sequences, 51 MP sequences and 36 NS sequences were obtained, including 20 whole genome sequences. Sequence comparison revealed they shared a high degree of homology （96%-99%） with known epidemic strains （A/Califomia/04/2009（H1N1）. Phylogenetic analysis showed that although the sequences were highly conserved, they clustered into a small number of groups with only a few distinct strains. Site analysis revealed three substitutions at loop 220 （221-228） of the HA receptor binding site in the 39 HA sequences： A/Hubei/86/2009 PKVRDQEG→PKVRDQEA, A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER, A/Hubei/75/2009 PKVRDQEG→PKVRDQGG, the A/Hubei/75/2009 was isolated from an acute case, while the other two were from patients with mild symptoms. Other key sites such as 119, 274, 292 and 294 amino acids of NA protein,627 of PB2 protein were conserved. Meanwhile, all the M2 protein sequences possessed the Ser32Asn mutation, suggesting that these viruses were resistant to adamantanes. Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.
基金Supported by Beijing Clinical Study(Z111107058811025)Beijing Government Excellent Person Sponsor Program
文摘Objective To investigate the clinical features and treatment of placenta previa complicated with previous caesarean section. Methods The clinical data of 29 patients with placenta previa complicated with a previous caesarean section (RCS group) admitted in Peking Union Medical College Hospital during a period from 2003 to 2011 were retrospectively reviewed and compared with those of 243 patients with placenta previa without a previous caesarean section (FCS group) during the same period. Results There was no difference in the mean age (28.9±3.6 vs. 28.1±4.5 years) and the average gravidity (2.35±1.48 vs. 2.21±1.53) between RCS group and FCS group (all P>0.05). The RCS group had more preterm births (24.1% vs. 13.2%), complete placenta previa (55.2% vs. 4.9%), placenta accreta (34.5% vs. 2.5%), more blood loss during caesarean section (1412±602 vs. 648±265 mL), blood transfusion (51.7% vs. 4.9%), disseminated intravascular coagulation (13.8% vs. 2.1%), and obstetric hysterectomy (13.8% vs. 0.8%) than the FCS group (all P<0.05). The preterm infant rate (30.0% vs. 13.0%), neonatal asphyxia rate (10.0% vs. 4.9%), and perinatal mortality rate (6.7% vs. 0.4%) of the RCS group were higher than those of the FCS group (all P<0.05). Conclusions More patients had complete placenta previa and placenta accreta, postpartum hemorrhage, transfusion, uterine packing, obstetric hysterectomy, and perinatal morbidity in the placenta previa patients with previous caesarean section. The patient should be informed of the risk and unnecessary first cesarean sections should be avoided.
基金supported by grants from the National Program on Key Basic Research Project of China(973 Program),No.2014CB542200the National Natural Science Foundation of China,No.31271284,81171146,31100860+1 种基金Program for Innovative Research Team in University of Ministry of Education of China,No.IRT1201the Natural Science Foundation of Beijing of China,No.7142164
文摘Multiple-bud regeneration, i.e., multiple amplification, has been shown to exist in peripheral nerve regeneration. Multiple buds grow towards the distal nerve stump during proximal nerve fiber regeneration. Our previous studies have verified the limit and validity of multiple ampli- fication of peripheral nerve regeneration using small gap sleeve bridging of small donor nerves to repair large receptor nerves in rodents. The present study sought to observe multiple ampli- fication of myelinated nerve fiber regeneration in the primate peripheral nerve. Rhesus monkey models of distal ulnar nerve defects were established and repaired using muscular branches of the right forearm pronator teres. Proximal muscular branches of the pronator teres were su- tured into the distal ulnar nerve using the small gap sleeve bridging method. At 6 months after suture, two-finger flexion and mild wrist flexion were restored in the ulnar-sided injured limbs of rhesus monkey. Neurophysiological examination showed that motor nerve conduction veloc- ity reached 22.63 _＋ 6.34 m/s on the affected side of rhesus monkey. Osmium tetroxide staining demonstrated that the number of myelinated nerve fibers was 1,657 ＋ 652 in the branches of pronator teres of donor, and 2,661 ~ 843 in the repaired ulnar nerve. The rate of multiple amplification of regenerating myelinated nerve fibers was 1.61. These data showed that when muscular branches of the pronator teres were used to repair ulnar nerve in primates, effective regeneration was observed in regenerating nerve fibers, and functions of the injured ulnar nerve were restored to a certain extent. Moreover, multiple amplification was subsequently detected in ulnar nerve axons.
基金supported by grants from the National Program on Key Basic Research Project of China(973 Program),No.2014CB542200Program for Innovative Research Team in University of Ministry of Education of China,No.IRT1201+1 种基金the National Natural Science Foundation of China,No.31271284,31171150,81171146,30971526,31100860,31040043Program for New Century Excellent Talents in University of Ministry of Education of China,No.BMU20110270
文摘In China, there are approximately 20 million people suffering from peripheral nerve injury and this number is increasing at a rate of 2 million per year. These patients cannot live or work independently and are a heavy responsibility on both family and society because of extreme disability and dysfunction caused by peripheral nerve injury （PNI）. Thus, repair of PNI has become a major public health issue in China.
基金funded by the National Natural Science Foundation of China,No.31571236,31571235(to YHK,PXZ)National Key Research and Development Program of China,No.2016YFC1101604(to DYZ)+3 种基金National Key Basic Research Program of China(973 Program),No.2014CB542200(to BGJ)Ministry of Education Innovation Program of China,No.IRT_16R01(to BGJ)Beijing Science and Technology New Star Cross Program of China,No.2018019(to PXZ)Peking University People’s Hospital Research and Development Funds,No.RDH2017-01(to HLX)
文摘Our previous studies have confirmed that during nerve transposition repair to injured peripheral nerves, the regenerated nerve fibers of motor neurons in the anterior horn of the spinal cord can effectively repair distal nerve and target muscle tissue and restore muscle motor function. To observe the effect of nerve regeneration and motor function recovery after several types of nerve transposition for median nerve defect(2 mm), 30 Sprague-Dawley rats were randomly divided into sham operation group, epineurial neurorrhaphy group, musculocutaneous nerve transposition group, medial pectoral nerve transposition group, and radial nerve muscular branch transposition group. Three months after nerve repair, the wrist flexion test was used to evaluate the recovery of wrist flexion after regeneration of median nerve in the affected limbs of rats. The number of myelinated nerve fibers, the thickness of myelin sheath, the diameter of axons and the cross-sectional area of axons in the proximal and distal segments of the repaired nerves were measured by osmic acid staining. The ratio of newly produced distal myelinated nerve fibers to the number of proximal myelinated nerve fibers was calculated. Wet weights of the flexor digitorum superficialis muscles were measured. Muscle fiber morphology was detected using hematoxylin-eosin staining. The cross-sectional area of muscle fibers was calculated to assess the recovery of muscles. Results showed that wrist flexion function was restored, and the nerve grew into the distal effector in all three nerve transposition groups and the epineurial neurorrhaphy group. There were differences in the number of myelinated nerve fibers in each group. The magnification of proximal to distal nerves was 1.80, 3.00, 2.50, and 3.12 in epineurial neurorrhaphy group, musculocutaneous nerve transposition group, medial pectoral nerve transposition group, and radial nerve muscular branch transposition group, respectively. Nevertheless, axon diameters of new nerve fibers, cross-sectional areas of axons, thicknesses of myelin sheath, wet weights of flexor digitorum superficialis muscle and cross-sectional areas of muscle fibers of all three groups of donor nerves from different anterior horn motor neurons after nerve transposition were similar to those in the epineurial neurorrhaphy group. Our findings indicate that donor nerve translocation from different anterior horn motor neurons can effectively repair the target organs innervated by the median nerve. The corresponding spinal anterior horn motor neurons obtain functional reinnervation and achieve some degree of motor function in the affected limbs.
基金This study was supported by the National Natural Science Foundation of China,No.31571236(to YHK)Science and Technology Planning Project of Beijing of China,No D161100002816001+1 种基金the National Key Research and Development Program of China,No.2016YFC1101604(to DYZ)the Ministry of Education Innovation Program of China,No.IRT_16R01.
文摘Complex pathological changes occur during the development of spinal cord injury(SCI),and determining the underlying molecular events that occur during SCI is necessary for the development of promising molecular targets and therapeutic strategies.This study was designed to explore differentially expressed genes(DEGs)associated with the acute and chronic stages of SCI using bioinformatics analysis.Gene expression profiles(GSE45006,GSE93249,and GSE45550)were downloaded from the Gene Expression Omnibus database.SCI-associated DEGs from rat samples were identified,and Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed.In addition,a protein-protein interaction network was constructed.Approximately 66 DEGs were identified in GSE45550 between 3–14 days after SCI,whereas 2418 DEGs were identified in GSE450061–56 days after SCI.Moreover,1263,195,and 75 overlapping DEGs were identified between these two expression profiles,3,7/8,and 14 days after SCI,respectively.Additionally,16 overlapping DEGs were obtained in GSE450061–14 days after SCI,including Pank1,Hn1,Tmem150c,Rgd1309676,Lpl,Mdh1,Nnt,Loc100912219,Large1,Baiap2,Slc24a2,Fundc2,Mrps14,Slc16a7,Obfc1,and Alpk3.Importantly,3882 overlapping DEGs were identified in GSE932491–6 months after SCI,including 3316 protein-coding genes and 567 long non-coding RNA genes.A comparative analysis between GSE93249 and GSE45006 resulted in the enrichment of 1135 overlapping DEGs.The significant functions of these 1135 genes were correlated with the response to the immune effector process,the innate immune response,and cytokine production.Moreover,the biological processes and KEGG pathways of the overlapping DEGs were significantly enriched in immune system-related pathways,osteoclast differentiation,the nuclear factor-κB signaling pathway,and the chemokine signaling pathway.Finally,an analysis of the overlapping DEGs associated with both acute and chronic SCI,assessed using the expression profiles GSE93249 and GSE45006,identified four overlapping DEGs:Slc16a7,Alpk3,Lpl and Nnt.These findings may be useful for revealing the biological processes associated with SCI and the development of targeted intervention strategies.
基金supported by the National Department Public Benefit Research Foundation (201103032)
文摘To understand the molecular characteristics of China human rabies vaccine strains, we report the full-length genome of the aG strain and present a comprehensive analysis of this strain and almost all available lyssavirus genomes （58 strains） from GenBank （as of Jan 6, 2011）. It is generally considered that the G protein plays a predominant role in determining the pathogenicity of the virus, to this end we predicted the tertiary structure of the G protein of aG strain, CTN 181 strain and wild type strain HN 10 based on the crystal structure of Vesicular stomatitis virus （VSV） G. The predicted RABV G structure has a similar topology to VSV G and the ectodomain can be divided into 4 distinct domains DI - DIV. By mapping the characterized mutations to this structure between China vaccine strains and their close street strains, we speculate that the G303（P-H） mutations of CTN181 and HN10 causing D II 3D change may be associated with the attenuated virulence in both strains. Specifically, the two signature mutations （G165P and G231P） in the aG strain are withinβsheets, suggesting that both sites are of structural importance.
基金supported by a grants from the National Program on Key Basic Research Project(973 Program),No.2014CB542200the Innovative Research Team by the Ministry of Education,No.IRT1201+1 种基金the National Natural Science Foundation of China,No.31271284,31171150,81171146,30971526,31040043,31371210,81372044,31471144the Beijing Municipal Natural Science Foundation of China,No.7142164
文摘The purpose of this study was to investigate the effect of four fluorescent dyes, True Blue（TB）, Fluoro-Gold（FG）, Fluoro-Ruby（FR）, and 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate（Di I）, in retrograde tracing of rat spinal motor neurons. We transected the muscle branch of the rat femoral nerve and applied each tracer to the proximal stump in single labeling experiments, or combinations of tracers（FG-Di I and TB-Di I） in double labeling experiments. In the single labeling experiments, significantly fewer labeled motor neurons were observed after FR labeling than after TB, FG, or Di I, 3 days after tracer application. By 1 week, there were no significant differences in the number of labeled neurons between the four groups. In the double-labeling experiment, the number of double-labeled neurons in the FG-Di I group was not significantly different from that in the TB-Di I group 1 week after tracer application. Our findings indicate that TB, FG, and Di I have similar labeling efficacies in the retrograde labeling of spinal motor neurons in the rat femoral nerve when used alone. Furthermore, combinations of Di I and TB or FG are similarly effective. Therefore, of the dyes studied, TB, FG and Di I, and combinations of Di I with TB or FG, are the most suitable for retrograde labeling studies of motor neurons in the rat femoral nerve.
基金supported by grants from the National Department Public Benefit Research Foundation (201103032)
文摘Dear Editor, We report the results of evolutionary history estimation of the lyssaviruses based on an analysis of the Glycoprotein (G) sequences gene using the BEAST software package. The most recent common ancestor (TMRCA) of all the lyssavirus strains was estimated to be approximately 5030 years (95% HPD 3988-6069 years), and there was a significant spread of the rabies virus throughout the world range in the last 200 years, consistent with significant time points in development and migration of human civilizations.
基金funded by the National Natural Science Foundation of China,No.31571236,31571235(to YHK,PXZ)National Key Research and Development Program of China,No.2016YFC1101604(to DYZ)+2 种基金National Key Basic Research Program of China(973 Program),No.2014CB542200(to BGJ)Ministry of Education Innovation Program of China,No.IRT_16R01(to BGJ)Beijing Science and Technology New Star Cross Program of China,No.2018019(to PXZ)
文摘Multiple regeneration of axonal buds has been shown to exist during the repair of peripheral nerve injury, which confirms a certain repair potential of the injured peripheral nerve. Therefore, a systematic nerve transposition repair technique has been proposed to treat severe peripheral nerve injury. During nerve transposition repair, the regenerated nerve fibers of motor neurons in the anterior horn of the spinal cord can effectively grow into the repaired distal nerve and target muscle tissues, which is conducive to the recovery of motor function. The aim of this study was to explore regeneration and nerve functional recovery after repairing a long-segment peripheral nerve defect by transposition of different donor nerves. A long-segment(2 mm) ulnar nerve defect in Sprague-Dawley rats was repaired by transposition of the musculocutaneous nerve, medial pectoral nerve, muscular branches of the radial nerve and anterior interosseous nerve(pronator quadratus muscle branch). In situ repair of the ulnar nerve was considered as a control. Three months later, wrist flexion function, nerve regeneration and innervation muscle recovery in rats were assessed using neuroelectrophysiological testing, osmic acid staining and hematoxylin-eosin staining, respectively. Our findings indicate that repair of a long-segment ulnar nerve defect with different donor nerve transpositions can reinnervate axonal function of motor neurons in the anterior horn of spinal cord and restore the function of affected limbs to a certain extent.
文摘Hyperlipidemia(HLP)is a long-known risk factor for a series of cardiovascular and cerebrovascular diseases,such as atherosclerosis,coronary heart disease,hypertension and so on.With its increasing incidence,the prevention and treatment of HLP has also become an important research topic around the world.Traditional Chinese medicine(TCM)has been used to treat HLP for a long time with its better therapeutic efficacy,less side effects and wider indications compared with western medicine.In this review,we summarized the pathogenesis of HLP,the research situation of disease-related targets,and the treatment progress of TCM by conducting literature research and sorting out relevant information,in order to provide reference for further research of HLP and prevent the occurrence of cardiovascular and cerebrovascular diseases.
文摘Dear Editor,Nucleotide and protein sequences of isolates collectedfrom infected populations can be useful for determiningthe threats,such as host adaptation,which are associatedwith the emergence of new lineages.March 2013 saw thefirst reports of a new H7N9 lineage in Shanghai,Chinathat saw a gradual increase in the number of cases;but,by 17th May 2013,four Chinese provinces had
基金supported by the National Key Plan for Scientific Research and Development of China(2021YFC2301305)the National Natural Science Foundation of China(92169106)+6 种基金the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(2021-PT180-001)Capital's Funds for health Improvement and Research(shoufa-1G-1131)the CAMS Innovation Fund for Medical Sciences(2021-I2M-1-061,2022-I2M-2-004,2023-PT330-01,2023-I2M-2-005)Suzhou science and technology development plan(szs2020311)Natural Science Foundation of Jiangsu Province(Grants No.BK20220278)Jiangsu Provincial Key Project of Science and Technology Plan(Grants No.BE2023601),Scientific research project of Jiangsu health commission(DX202301)the NCTIB Fund for R&D Platform for Cell and Gene Therapy.We gratefully acknowledge the CNCB,CoV-Spectrum,and GISAID databases,as well as all the authors who originated and submitted the SARS-CoV-2 sequences,for generously sharing their work through open databases.
文摘China's dynamic zero-COVID policy has effectively curbed the spread of SARS-CoV-2,while inadvertently creating immunity gaps within its population.Subsequent surges in COVID-19 cases linked to various SARS-CoV-2 lineages post-policy termination necessitate a thorough investigation into the epidemiological landscape.This study addresses this issue by analyzing a comprehensive dataset of 39,456 high-quality genomes collected nationwide over an 11-month period since policy termination.Through lineage assignment,phylogenetic analysis,pandemic pattern comparison,phylodynamic reconstruction,and recombination detection,we found that China's postepidemic period could be divided into three stages,along with dynamic changes in dominant lineages.Geographical clustering of similar lineages implies the importance of cross-border cooperation among neighboring regions.Compared to the USA,UK,and Japan,China exhibits unique trajectories of lineage epidemics,characterized by initial lagging followed by subsequent advancement,indicating the potential influence of diverse prevention and control policies on lineage epidemic patterns.Hong Kong,Shanghai,and Hubei emerge as pivotal nodes in the nationwide spread,marking a shift in the transmission center from east to central regions of China.Although China hasn't experienced significant variant emergence,the detection and validation of the novel recombination event,XCN lineage,underscore the ongoing virus evolution.Overall,this study systematically analyzes the spatiotemporal transmission of SARS-CoV-2 virus in China since the termination of the dynamic zeroCOVID policy,offering valuable insights for regional surveillance and evidence-based public health policymaking.
文摘The authors reply:We deeply appreciated your interest in our research.In our study,the conclusion that femoral head necrosis induced by large doses of steroid pulse therapy in SARS patients was partially reversible was based on the results of the volume of femoral head necrosis on MRI combined with the ARCO stage.The volume of osteonecrosis decreased significantly from 2003(38.83%±21.01%)to 2005(30.38%±20.23%)(P=0.0002),then declined slowly from 2005 to 2013(28.99%±20.59%)and plateaued in 2018(25.52%±15.51%).The ARCO stages of 17 limbs in ten patients stabilized or improved during follow-up,while the stages of six limbs in four patients reflected deterioration.
