[Interpretation of the 2023 "Guidelines for parenteral nutrition in preterm infants: the American Society for Parenteral and Enteral Nutrition"]. / ã€Šç¾Žå›½è‚ å¤–è‚ å† è¥å »å­¦ä¼šæ—©äº§å„¿è‚ å¤–è¥å »æŒ‡å—ï¼ˆ2023）》解读.

The "Guidelines for parenteral nutrition in preterm infants: the American Society for parenteral and enteral nutrition" were developed by the American Society for Parenteral and Enteral Nutrition and published in the Journal of Parenteral and Enteral Nutrition in September 2023. The guidelines provide recommendations on 12 key clinical questions regarding parenteral nutrition (PN) for preterm infants. In comparison to similar guidelines, this set offers more detailed perspectives on PN for preterm infants. It presents evidence-based recommendations for the commencement time, nutrient dosage, and composition of PN, considering primary outcomes such as growth and development, as well as secondary outcomes like sepsis, retinopathy of prematurity, parenteral nutrition-related liver disease, and jaundice. This article aims to interpret the guidelines to provide a reference for colleagues in the field.

[Interpretation of the UK screening and treatment of retinopathy of prematurity updated 2022 guidelines]. / è‹±å›½æ—©äº§å„¿è§†ç½‘è†œç— å˜çš„ç­›æŸ¥å’Œæ²»ç–—æŒ‡å—2022更新版解读.

The UK screening and treatment of retinopathy of prematurity (ROP) updated 2022 guidelines were developed by a multidisciplinary guideline development group from the Royal College of Paediatrics and Child Health and the Royal College of Ophthalmologists, following the standards of the National Institute for Health and Care Excellence. They were published on the websites of the Royal College of Paediatrics and Child Health and the Royal College of Ophthalmologists in March 2022, and formally published in Early Human Development in March 2023. The guidelines provide evidence-based recommendations for the screening and treatment of ROP. The most significant change in the 2022 updated version compared to the previous guidelines is the lowering of the gestational age screening criterion to below 31 weeks. The treatment section covers treatment indications, timing, methods, and follow-up visits of ROP. This article interprets the guidelines and compares them with ROP guidelines/consensus in China, providing a reference for domestic peers.

Cellular Localization and Distribution of TGF-ß1, GDNF and PDGF-BB in the Adult Primate Central Nervous System.

The available data on the localization of transforming growth factor beta1 (TGF-ß1), glial cell line-derived neurotrophic factor (GDNF), and platelet-derived growth factor-BB (PDGF-BB) in the adult primate and human central nervous system (CNS) are limited and lack comprehensive and systematic information. This study aimed to investigate the cellular localization and distribution of TGF-ß1, GDNF, and PDGF-BB in the CNS of adult rhesus macaque (Macaca mulatta). Seven adult rhesus macaques were included in the study. The protein levels of TGF-ß1, PDGF-BB, and GDNF in the cerebral cortex, cerebellum, hippocampus, and spinal cord were analyzed by western blotting. The expression and location of TGF-ß1, PDGF-BB, and GDNF in the brain and spinal cord was examined by immunohistochemistry and immunofluorescence staining, respectively. The mRNA expression of TGF-ß1, PDGF-BB, and GDNF was detected by in situ hybridization. The molecular weight of TGF-ß1, PDGF-BB, and GDNF in the homogenate of spinal cord was 25 KDa, 30 KDa, and 34 KDa, respectively. Immunolabeling revealed GDNF was ubiquitously distributed in the cerebral cortex, hippocampal formation, basal nuclei, thalamus, hypothalamus, brainstem, cerebellum, and spinal cord. TGF-ß1 was least distributed and found only in the medulla oblongata and spinal cord, and PDGF-BB expression was also limited and present only in the brainstem and spinal cord. Besides, TGF-ß1, PDGF-BB, and GDNF were localized in the astrocytes and microglia of spinal cord and hippocampus, and their expression was mainly found in the cytoplasm and primary dendrites. The mRNA of TGF-ß1, PDGF-BB, and GDNF was localized to neuronal subpopulations in the spinal cord and cerebellum. These findings suggest that TGF-ß1, GDNF and PDGF-BB may be associated with neuronal survival, neural regeneration and functional recovery in the CNS of adult rhesus macaques, providing the potential insights into the development or refinement of therapies based on these factors.

[Interpretation of "International guidelines regarding the role of IVIG in the management of Rh- and ABO-mediated haemolytic disease of the newborn"]. / ã€Šå›½é™ æŒ‡å—ï¼šé™è„‰æ³¨å°„å ç–«çƒè›‹ç™½åœ¨æ²»ç–—Rh和ABOæ–°ç”Ÿå„¿æº¶è¡€ç— ä¸­çš„ä½œç”¨ã€‹è§£è¯».

International guidelines regarding the role of intravenous immunoglobulin (IVIG) in the management of Rh- and ABO-mediated haemolytic disease of the newborn was drafted by an international panel of experts in the fields of hematology, neonatology, and blood transfusion and was published in British Journal of Haematology on March 16, 2022. The guidelines summarize the evidence-based practice of IVIG in Rh- and ABO-mediated haemolytic disease of the newborn and propose related recommendations. The guidelines recommend that IVIG should not be applied as a routine treatment regimen for Rh- and ABO-mediated haemolytic disease of the newborn in order to reduce exchange transfusion (ET), and the best time to apply IVIG remains unclear in the situations where hyperbilirubinaemia is severe (approaching or exceeding the ET threshold) or ET cannot be implemented. These guidelines are formulated with rigorous methods, but with the lower quality of evidence.

Effectiveness of azithromycin mass drug administration on trachoma: a systematic review.

BACKGROUNDS: Azithromycin mass drug administration (MDA) is a key part of the strategy for controlling trachoma. This systematic review aimed to comprehensively summarize the present studies of azithromycin MDA on trachoma; provide an overview of the impact of azithromycin MDA on trachoma in different districts; and explore the possible methods to enhance the effectiveness of azithromycin MDA in hyperendemic districts. METHODS: PubMed, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and ClinicalTrials.gov were searched up to February 2021 with no language restriction. Studies reporting the effect of azithromycin MDA on trachoma were included. Mathematical modeling studies, animal studies, case reports, and reviews were excluded. The trachomatous inflammation-follicular (TF) <5.0% was used to judge the effect of azithromycin MDA on eliminating trachoma as a public health problem. Two researchers independently conducted the selection process and risk of bias assessment. RESULTS: A total of 1543 studies were screened, of which 67 studies including 13 cluster-randomized controlled trials and 54 non-randomized studies were included. The effect of azithromycin MDA on trachoma was closely related to the baseline prevalence in districts. For the districts with baseline prevalence between 5.0% and 9.9%, a single round of MDA achieved a TF <5.0%. For the districts with baseline between 10.0% and 29.9%, annual MDA for 3 to 5 years reduced TF <5.0%. However, for the districts with high level of baseline prevalence (TF >30.0%), especially with baseline TF >50.0%, annual MDA was unable to achieve the TF <5.0% even after 5 to 7 years of treatment. Quarterly MDA is more effective in controlling trachoma in these hyperendemic districts. CONCLUSIONS: Azithromycin MDA for controlling trachoma depends on the baseline prevalence. The recommendation by the World Health Organization that annual MDA for 3 to 5 years in the districts with TF baseline >10.0% is not appropriate for all eligible districts.

Cerebral palsy in children born after assisted reproductive technology: a meta-analysis.

BACKGROUND: Several studies have assessed the association between cerebral palsy (CP) and assisted reproductive technology (ART), but the results remain controversial. We conducted a meta-analysis to evaluate the risk of CP after ART compared with natural conceptions and to examine CP risk separately in ART singletons, multiples and preterm births. METHODS: Web-based databases (PubMed, Embase, the Cochrane Library, and Web of Science) were searched until November 22, 2020. Studies which compare CP rates after ART with natural conceptions were included. The Newcastle-Ottawa Scale was used to assess the quality of the included studies. Effect estimates were extracted and combined using the fixed-effects or random-effects model depending on the heterogeneity test. RESULTS: There were nine studies included in the meta-analysis. The included studies were of moderate or high quality. A significantly higher risk of CP [odds ratio (OR) = 2.17, 95% confidence interval (CI) 1.72-2.74] was found in ART children (n = 89,214) compared with naturally conceived children (n = 4,160,745). The significantly higher risk decreased when data were restricted to singletons (OR = 1.36, 95% CI 1.16-1.59) and disappeared when data were restricted to multiples (OR = 1.05, 95% CI 0.86-1.29) or preterm births (OR = 1.53, 95% CI 0.66-3.56). Subgroup and sensitivity analyses indicated that the overall results were robust. CONCLUSIONS: The risk of CP is increased more than two-fold after ART. This increased risk is largely due to increased rates of multiple birth and preterm delivery in ART children.

[Role and mechanism of histone deacetylases in mouse neuronal development].

OBJECTIVE: To study the role and mechanism of histone deacetylase 1 (HDAC1) and histone deacetylase 2 (HDAC2) in mouse neuronal development. METHODS: The mice with Synapsin1-Cre recombinase were bred with HDAC1&2flox/flox mice to obtain the mice with neuron-specific HDAC1&2 conditional knockout (knockout group), and their littermates without HDAC1&2 knockout were used as the control group. The general status of the mice was observed and survival curves were plotted. Brain tissue samples were collected from the knockout group and the control group. Western blot and immunohistochemistry were used to measure the protein expression of related neuronal and axonal markers, neuronal nuclear antigen (NeuN), non-phosphorylated neurofilament heavy chain (np-NF200), and phosphorylated neurofilament heavy chain (p-NF200), as well as the downstream effector of the mTOR signaling pathway, phosphorylated S6 ribosomal protein (p-S6). RESULTS: The mice with HDAC1&2 conditional knockout usually died within one month after birth and were significantly smaller than those in the control group, with motor function abnormalities such as tremor and clasping of hindlimbs. Compared with the control group, the knockout group had significant reductions in the protein expression levels of NeuN, np-NF200, p-NF200, and p-S6 (P < 0.05; n=3). CONCLUSIONS: Deletion of HDAC1 and HDAC2 in mouse neurons results in reduced neuronal maturation and axonal dysplasia, which may be associated with the mTOR signaling pathway.

[Clinical features of coronavirus disease 2019 in children: a systemic review of severe acute respiratory syndrome, Middle East respiratory syndrome, and coronavirus disease 2019].

OBJECTIVE: To systematically summarize the clinical features of coronavirus disease 2019 (COVID-19) in children. METHODS: PubMed, Embase, Web of Science, The Cochrane Library, CNKI, Weipu Database, and Wanfang Database were searched for clinical studies on COVID-19 in children published up to May 21, 2020. Two reviewers independently screened the articles, extracted data, and assessed the risk of bias of the studies included. A descriptive analysis was then performed for the studies. Related indices between children with COVID-19 and severe acute respiratory syndromes (SARS) or Middle East respiratory syndrome (MERS) were compared. RESULTS: A total of 75 studies were included, with a total of 806 children with COVID-19. The research results showed that the age of the children ranged from 36 hours after birth to 18 years, with a male-female ratio of 1.21 : 1. Similar to SARS and MERS, COVID-19 often occurred with familial aggregation, and such cases accounted for 74.6% (601/806). The children with COVID-19, SARS, and MERS had similar clinical symptoms, mainly fever and cough. Some children had gastrointestinal symptoms. The children with asymptomatic infection accounted for 17.9% (144/806) of COVID-19 cases, 2.5% (2/81) of SARS cases, and 57.1% (12/21) of MERS cases. The children with COVID-19 and MERS mainly had bilateral lesions on chest imaging examination, with a positive rate of lesions of 63.4% (421/664) and 26.3% (5/19) respectively, which were lower than the corresponding positive rates of viral nucleic acid detection, which were 99.8% and 100% respectively. The chest radiological examination of the children with SARS mainly showed unilateral lesion, with a positive rate of imaging of 88.9% (72/81), which was higher than the corresponding positive rate of viral nucleic acid detection (29.2%). Viral nucleic acid was detected in the feces of children with COVID-19 or SARS, with positive rates of 60.2% (56/93) and 71.4% (5/7) respectively. The children with COVID-19 had a rate of severe disease of 4.6% (31/686) and a mortality rate of 0.1% (1/806), the children with SARS had a rate of severe disease of 1.5% (1/68) and a mortality rate of 0%, and those with MERS had a rate of severe disease of 14.3% (3/21) and a mortality rate of 9.5% (2/21). CONCLUSIONS: Children with COVID-19 have similar symptoms to those with SARS or MERS, mainly fever and cough. Asymptomatic infection is observed in all three diseases. Children with COVID-19 or SARS have milder disease conditions than those with MERS. COVID-19 in children often occurs with familial aggregation. Epidemiological contact history, imaging examination findings, and viral nucleic acid testing results are important bases for the diagnosis of COVID-19.

[Effect of irisin on hypoxic-ischemic brain damage in neonatal rats].

OBJECTIVE: To study the effect and mechanism of action of irisin on hypoxic-ischemic brain damage in neonatal rats. METHODS: A total of 248 7-day-old Sprague-Dawley rats were randomly divided into a sham-operation group, a model group, and low- and high-dose irisin intervention groups (n=62 each). The rats in the model and irisin intervention groups were given hypoxic treatment after right common carotid artery ligation to establish a model of hypoxic-ischemic brain damage. Those in the sham-operation group were given the separation of the right common carotid artery without ligation or hypoxic treatment. The rats in the high- and low-dose irisin intervention groups were given intracerebroventricular injection of recombinant irisin polypeptide at a dose of 0.30 µg and 0.15 µg respectively. Those in the model and sham-operation groups were given the injection of an equal volume of PBS. The water maze test was used to compare neurological behaviors between groups. TTC staining, hematoxylin-eosin staining and TUNEL staining were used to observe histopathological changes of the brain. Western blot was used to measure the expression of the apoptosis-related molecules cleaved-caspase-3 (CC3), BCL-2 and BAX. RESULTS: Compared with the sham-operation group, the model group had a significant increase in latency time and a significant reduction in the number of platform crossings (P<0.05). Compared with the model group, the high-dose irisin intervention group had a significant reduction in latency time and a significant increase in the number of platform crossings (P<0.05). Compared with the sham-operation group, the model group had massive infarction in the right hemisphere, with significant increases in karyopyknosis and karyorrhexis. Compared with the model group, the high-dose irisin intervention group had a smaller infarct area of the right hemisphere, with reductions in karyopyknosis and karyorrhexis. The model group had a significantly higher apoptosis rate of cells in the right cerebral cortex and the hippocampus than the sham-operation group. The high-dose irisin intervention group had a significantly lower apoptosis rate than the model group (P<0.05). At 24 and 48 hours after modeling, the sham-operation group had a significantly lower level of CC3 than the model group (P<0.05). Compared with the model group, the high-dose irisin intervention group had a significantly lower level of CC3 and a significantly higher BCL-2/BAX ratio (P<0.05). The low-dose irisin intervention group had similar laboratory markers and histopathological changes of the brain to the model group. CONCLUSIONS: Irisin can alleviate hypoxic-ischemic brain damage in neonatal rats in a dose-dependent manner, possibly by reducing cell apoptosis in the cerebral cortex and the hippocampus.

Regulation of hippocampal neuronal apoptosis and autophagy in mice with sepsis-associated encephalopathy by immunity-related GTPase M1.

AIMS: Sepsis-associated encephalopathy (SAE) is a common complication of severe sepsis. Our goal was to investigate the role of immunity-related GTPase M1 (IRGM1) in SAE and its underlying mechanism. METHODS: A mouse sepsis model was established by cecal ligation and perforation. SAE was diagnosed by behavior, electroencephalography, and somatosensory evoked potentials. Wild-type mice with SAE were treated with SB203580 to block the p38 mitogen-activated protein kinase (MAPK) signaling pathway. We assessed hippocampal histological changes and the expression of IRGM1, interferon-γ (IFN-γ), and p38 MAPK signaling pathway-related proteins. RESULTS: Immunity-related GTPase M1 and IFN-γ levels increased in the hippocampus, with apoptosis, autophagy, and the p38 MAPK signaling pathway activated in neurons. Administration of SB203580 to mice with SAE reduced apoptosis and autophagy. Relative to wild-type mice with SAE, the general condition of Irgm1-/- mice with SAE was worsened, the p38 MAPK signaling pathway was inhibited, and neuronal apoptosis and autophagy were reduced. The absence of IRGM1 exacerbated SAE, with higher p38 MAPK signaling pathway activity and increased apoptosis and autophagy. CONCLUSIONS: During SAE, IRGM1 can at least partially regulate apoptosis and autophagy in hippocampal neurons through the p38 MAPK signaling pathway.

[Pediatric projects funded by National Natural Science Foundation of China from 2009 to 2018: retrospect and prospects].

OBJECTIVE: To perform a review and data analysis of the pediatric projects funded by National Natural Science Foundation of China from 2009 to 2018, and to investigate the changes in key support areas, research interest, and research hotspots in pediatrics. METHODS: The database of National Natural Science Foundation of China was searched to screen out pediatric research projects in 2009-2018, and the changes in funding intensity and research direction were analyzed. RESULTS: From 2009 to 2018, a total of 1 017 pediatric projects were funded by National Natural Science Foundation of China, with 485 (47.69%) General Projects, 426 (41.89%) Youth Fund Projects, 73 (7.18%) Regional Research Programs, 16 (1.57%) Key Programs, 6 (0.59%) Outstanding Youth Fund Projects, 7 (0.69%) Overseas Programs, and 4 (0.39%) other programs. There was a seven-fold increase in the total amount of subsidies, which increased from 8.42 million yuan in 2009 to 66.25 million yuan in 2018. The projects with the Primary Discipline Code of reproductive system/perinatology/neonatology, nervous system and mental illness, or circulatory system received the highest amount of fund. CONCLUSIONS: The support of pediatric projects by National Natural Science Foundation of China continues to increase in the past ten years, and the main types of projects are General Projects and Youth Fund Projects. Neonatology, nervous system/mental illness, and circulatory diseases are the main directions of funded projects.

[Effect of prednisolone and adrenocorticotropic hormone in the treatment of infantile spasms: a Meta analysis].

OBJECTIVE: To compare the effect and safety of prednisolone and adrenocorticotropic hormone (ACTH) in the treatment of infantile spasms (IS). METHODS: Cochrane Library, Embase, PubMed, China Biology Medicine Disc, CNKI, and Wanfang Data were searched for clinical studies on the comparison between prednisolone and ACTH in the treatment of IS. Literature screening, data extraction, and quality assessment were performed. Review Manager 5.3 was used for Meta analysis. RESULTS: Five clinical studies were included according to the inclusion criteria and exclusion criteria. Meta analysis showed that there was no significant difference in the spasm remission rate, spasm remission time, complicating infection rate, and irritability rate between the prednisolone and ACTH treatment groups (P>0.05), but the disappearance rate of hypsarrhythmia in the electroencephalogram was higher in the ACTH treatment group than in the prednisolone treatment group (P<0.05). CONCLUSIONS: The available evidence shows no difference in the clinical efficacy of prednisolone versus ACTH in the treatment of IS. However, ACTH is superior to prednisolone in stabilizing EEG. The two therapies have no difference in the incidence of adverse reactions such as infection and irritability.

[A visualization analysis of current research on stem cell transplantation in the treatment of neonatal hypoxic-ischemic encephalopathy].

OBJECTIVE: To reveal the current research status on stem cell transplantation in the treatment of neonates with hypoxic-ischemic encephalopathy (HIE), and to summarize the recent hotspots of the research in this field. METHODS: Using the key words of "stem cells" and "HIE", a computerized search was performed for the articles in English published before June 1, 2018 in PubMed, EMBASE, and Web of Science. Microsoft Office Excel 2013 was used for the statistical analysis of key words. Bicomb 2.0 and VOSviewer 1.6.6 were used for the cluster analysis of hot words and plotting of knowledge maps, respectively. RESULTS: A total of 106 articles were included and 43 high-frequency key words were extracted. The words of "cell transplantation" and "hypoxia-ischemia" were in the core position of the co-word map. The cluster analysis showed that the studies of stem cell transplantation in the treatment of neonatal HIE mainly focused on umbilical cord blood cell transplantation (32.6%), mesenchymal stem cells and neural stem cells (29.5%), perinatal brain injury (28.1%), and other topics (9.8%). CONCLUSIONS: In the current studies of stem cell transplantation in the treatment of neonatal HIE, umbilical cord blood cell transplantation, mesenchymal stem cells, neural stem cells, and perinatal brain injury are popular research topics at different levels.

[A review on the relationship between mitochondrial dysfunction and white matter injury in preterm infants].

White matter injury in preterm infants has a complex etiology and can lead to long-term neurocognitive and behavioral deficits, but there are still no specific treatment methods for this disease at present. More and more studies have shown that mitochondrial dysfunction plays an important role in the pathogenesis of white matter injury in preterm infants and might be a common subcellular mechanism of white matter developmental disorder, which involves oxidative stress, reduced ATP synthesis, and disequilibrium of calcium homeostasis. This article reviews the role of mitochondria in brain development and the mechanism of mitochondrial dysfunction, with a hope to perform early intervention of white matter injury in preterm infants by protecting mitochondrial function, so as to provide a reference for improving the neurodevelopmental outcome of preterm infants who survive.

[Effect of golden-hour body temperature bundle management on admission temperature and clinical outcome in preterm infants after birth].

OBJECTIVE: To study the effect of golden-hour body temperature bundle management strategy on admission temperature and clinical outcome in preterm infants with a gestational age of <34 weeks after birth. METHODS: The preterm infants who were born in the delivery room of the West China Second University Hospital of Sichuan University and admitted to the department of neonatology of this hospital within 1 hour after birth from December 2015 to June 2016 and from January to May, 2017 were enrolled. The 173 preterm infants who were admitted from January to May, 2017 were enrolled as the intervention group and were given golden-hour body temperature bundle management. The 164 preterm infants who were admitted from December 2015 to June 2016 were enrolled as the control group and were given conventional body temperature management. RESULTS: The intervention group had a significantly higher mean admission temperature than the control group (36.4±0.4°C vs 35.3±0.6°C; P<0.001). The incidence rate of hypothermia on admission in the intervention group was significantly lower than that in the control group (56.6% vs 97.6%; P<0.001). The intervention group had a significantly lower incidence rate of intracranial hemorrhage within one week after admission than the control group (15.0% vs 31.7%; P<0.05). CONCLUSIONS: Golden-hour body temperature bundle management for preterm infants within one hour after birth can reduce the incidence of hypothermia on admission and improve clinical outcome.

[Current status of the application of 1H-magnetic resonance spectroscopy in neonates with hypoxic-ischemic encephalopathy].

OBJECTIVE: To investigate the current status of the application of 1H-magnetic resonance spectroscopy (1H-MRS) in neonates with hypoxic-ischemic encephalopathy (HIE), and to describe the trend of research in the field. METHODS: PubMed, EMBASE, and Web of Science were searched for English articles published up to January 10, 2018, with the combination of key words and MeSH terms. The articles were screened according to inclusion and exclusion criteria. Excel 2016, Bicomb 2.0, and VOSviewer1.6.6 were used to analyze the key words, to perform a cluster analysis of hot words, and to plot the knowledge map. RESULTS: A total of 66 articles were included, and 27 high-frequency key words were extracted. The results showed that 1H-MRS was mainly used in four directions of the clinical practice and scientific research on HIE. In clinical practice, 1H-MRS attracted wide attention as a clinical examination for HIE and a tool for prognostic evaluation; in scientific research, 1H-MRS was used in animal experiments and studies associated with mild hypothermia therapy. CONCLUSIONS: As an auxiliary means of magnetic resonance imaging, 1H-MRS plays an important role in investigating the pathogenesis of neonatal HIE, improving existing therapies, and evaluating the prognosis of neonates with HIE.

[Protective effect of astrocyte exosomes on hypoxic-ischemic neurons].

OBJECTIVE: To study the effect of astrocyte exosomes on hypoxic-ischemic neurons. METHODS: Rat astrocytes were cultured in vitro, and differential centrifugation was used to obtain the exosomes from the cell supernatant. Transmission electron microscopy, Nanosight, and Western blot were used for the identification of exosomes. BCA method was used to measure the concentration of exosomes. Rat neurons were cultured in vitro and then divided into control group, exosome group, oxygen glucose deprivation (OGD) group, and OGD+exosome group (n=3 each). The OGD and OGD+exosome groups were cultured in glucose-free medium under the hypoxic condition. The exosome and OGD+exosome groups were treated with exosomes at a final concentration of 22 μg/mL. The control and OGD groups were given an equal volume of phosphate-buffered saline. ELISA was used to measure the level of lactate dehydrogenase (LDH) in neurons. The terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling was used to measure the apoptotic index of neurons. RESULTS: The identification of exosomes showed that the exosomes extracted by differential centrifugation had the features of exosomes. Compared with the control and exosome groups, the OGD group had significant increases in LDH level and apoptotic index (P<0.05). Compared with the OGD group, the OGD+exosome group had significant reductions in LDH level and apoptotic index (P<0.05). CONCLUSIONS: The exosomes from astrocytes have a protective effect on neurons with hypoxic-ischemic injury.

[Neuroprotective effects of oligodendrocyte precursor cells on white matter damage in preterm infants].

White matter damage, characterized by demyelination due to the damage of oligodendrocyte precursor cells (OPCs), is the most common type of brain damage in preterm infants. Survivors are often subject to long-term neurodevelopmental sequelae because of the lack of effective treatment. In recent years, it has been found that cell transplantation has the potential for the treatment of white matter damage. OPCs are frequently used cells in cell transplantation therapy. With abilities of migration and myelinization, OPCs are the best seed cells for the treatment of white matter damage. Several studies have found that OPCs may not only replace impaired cells to reconstruct the structure and function of white matter, but also inhibit neuronal apoptosis, promote the proliferation of endogenous neural stem cells, and enhance the repairment of the blood-brain barrier. However, the clinical application of OPC transplantation therapy faces many challenges, such as the effectiveness, risk of tumorigenesis and immune rejection. With reference to these studies, this article reviewed the development of myelination, the obtainment of OPCs, the therapeutic mechanism as well as application research, and analyzed the current challenges of OPC transplantation, in order to provide a new direction for clinical treatment of white matter damage in preterm infants.

[Research advances in immune tolerance of allogeneic cell transplantation in preterm infants].

Preterm infants are a special group, and related severe neurological, respiratory, and digestive disorders have high disability/fatality rates. Allogeneic cell transplantation may be an effective method for the prevention and treatment of these diseases. At present, animal studies have been conducted for allogeneic cell transplantation in the treatment of hypoxic-ischemic encephalopathy, bronchopulmonary dysplasia, and necrotizing enterocolitis. The main difficulty of this technique is graft-versus-host reaction (GVHR), and successful induction of immune tolerance needs to be achieved in order to solve this problem. This article reviews the research advances in immune tolerance of allogeneic cell transplantation in preterm infants.

[Research advances in mesenchymal stem cell-derived exosomes in treatment of brain injury].

Mesenchymal stem cell (MSC) transplantation is considered one of the most promising therapeutic strategies for the repair of brain injuries and plays an important role in various links of nerve repair. Recent studies have shown that MSC-derived exosomes may dominate the repair of brain injuries and help to promote angiogenesis, regulate immunity, inhibit apoptosis, and repair the nerves, and therefore, they have a great potential in the treatment of brain injuries in neonates. With reference to these studies, this article reviews the mechanism of action of exosomes in the repair of brain injuries and related prospects and challenges, in order to provide new directions for the treatment of brain injuries in neonates with stem cells.