Lactate, with a chemical formula of C₃H₆O₃, is an intermediate product of glucose metabolism in the body and a raw material for hepatic gluconeogenesis. Under physiological resting conditions, the body mainly relies on aerobic oxidation of sugar and fat for energy supply, so the blood lactate concentration is lower. However, during exercise, the enhanced glycolysis in skeletal muscles leads to the significant release of lactate into the bloodstream, causing a marked increase in blood lactate concentration. Traditionally, lactate has been regarded as a metabolic waste product of glycolysis and a contributor to exercise-induced fatigue. Nevertheless, recent studies have revealed that, in humans, lactate is a major vehicle for carbohydrate carbon distribution and metabolism, serving not only as an energy substance alongside glucose but also as a vital component in various biological pathways involved in cardiac energetics, muscle adaptation, brain function, growth and development, and inflammation therapy. Two primary pathways can elevate lactate levels in neurons during exercise. One is peripheral skeletal muscle-derived lactate, which can enter the bloodstream and cross the blood-brain barrier into the brain with the assistance of monocarboxylate transporters (MCTs) from the solute carrier family 16 (SLC16). The other is the central brain-derived pathway. During exercise, neuronal activity is enhanced, promoting the secretion of neuroactive substances such as glutamate, norepinephrine, and serotonin in the brain. This activates astrocytes to break down glycogen into lactate and stimulates glutamate from the presynaptic terminal into the synaptic cleft. It upregulates the glucose transport protein-1 (GLUT-1) expression, allowing astrocytes to convert glucose into lactate through glycolysis. The lactate is produced via peripheral pathways and central pathways during exercise are transported by astrocyte membrane monocarboxylate transporters MCT1 and MCT4 to the extracellular space, where neurons take it up through neuronal cell membrane MCT2. The lactate in neurons can serve as an alternative energy source of glucose for neuronal functional activities, meeting the increased energy demands of synaptic activity during exercise, and maintaining energy balance and normal physiological function in the brain. Additionally, acting as a signaling molecule lactate can enhance synaptic plasticity through the SIRT1/PGC-1α/FNDC5 and ERK1/2 signaling pathways, lactate can promote angiogenesis by upregulating VEGF-A expression through the PI3K/Akt and ERK1/2 signaling pathways, stimulate neurogenesis via the Akt/PKB signaling pathway, and reduce neuroinflammation through activation of the “lactate timer”. Overall, lactate contributes to the protection of neurons, the promotion of learning and memory, the enhancement of synaptic plasticity, and the reduction of neuroinflammation in the nervous system. While lactate may serve as a potential mediator for information exchange between the peripheral and central nervous systems during exercise, further experimental research is needed to elucidate its action mechanisms in the nervous system. In addition, future studies should utilize advanced neurophysiological and molecular biology techniques to uncover the importance of lactate in maintaining brain function and preventing neurological diseases. Accordingly, this article first reviews the historical research on lactate, then summarizes the metabolic characteristics and neuronal sources of lactate, and finally explores the role and mechanisms of exercise-induced lactate in the nervous system, aiming to provide new perspectives and targets for understanding the mechanisms underlying exercise promotion of brain health.

The Hazardous Drug Exposure Management: Information for Healthcare Settings (2023 Edition) released by the National Institute for Occupational Safety and Health (NIOSH) of US provided detailed protection recommendations for medical personnel to mitigate the risks of occupational exposure to hazardous drugs. This study reviewed the literature in terms of hazard identification, occupational exposure assessment, risk assessment, risk management planning, and waste and spill control. It also explored the precautions for each step of hazardous drug handling, aiming to raise medical personnel's awareness of hazardous drug protection and improve their self-protection skills. The findings provided valuable references for medical institutions to develop hazardous drug disposal plans and reduce employees' exposure to hazardous drugs and occupational injuries.

Objective: To systematically analyze the revisions content and technological development trends of microbiological standards in the Chinese Pharmacopoeia (ChP) 2025 Edition, and explore its novel requirements in risk-based pharmaceutical product lifecycle management.
Methods: A comprehensive review was conducted on 26 microbiological-related standards to summarize the revision directions and scientific implications from perspectives including the revision overview, international harmonization of microbiological standards, risk-based quality management system, and novel tools and methods with Chinese characteristics.
Results: The ChP 2025 edition demonstrates three prominent features in microbiological-related standards: enhanced international harmonization, introduced emerging molecular biological technologies, and established a risk-based microbiological quality control system.
Conclusion: The new edition of the Pharmacopoeia has systematically constructed a microbiological standard system, which significantly improves the scientificity, standardization and applicability of the standards, providing a crucial support for advancing the microbiological quality control in pharmaceutical industries of China.

BACKGROUND:Flap transplantation technique is a commonly used surgical procedure for the treatment of severe tissue defects,but postoperative flap necrosis is easily triggered by ischemia-reperfusion injury.Therefore,it is still an important research topic to improve the survival rate of transplanted flaps. OBJECTIVE:To review the pathogenesis and latest treatment progress of flap ischemia-reperfusion injury. METHODS:CNKI,WanFang Database and PubMed database were searched for relevant literature published from 2014 to 2024.The search terms used were"flap,ischemia-reperfusion injury,inflammatory response,oxidative stress,Ca2+overload,apoptosis,mesenchymal stem cells,platelet-rich plasma,signaling pathways,shock wave,pretreatment"in Chinese and English.After elimination of irrelevant literature,poor quality and obsolete literature,77 documents were finally included for review. RESULTS AND CONCLUSION:Flap ischemia/reperfusion injury may be related to pathological factors such as inflammatory response,oxidative stress response,Ca2+overload,and apoptosis,which can cause apoptosis of vascular endothelial cells,vascular damage and microcirculation disorders in the flap,and eventually lead to flap necrosis.Studies have found that mesenchymal stem cell transplantation,platelet-rich plasma,signaling pathway modulators,shock waves,and pretreatment can alleviate flap ischemia/reperfusion injuries from different aspects and to varying degrees,and reduce the necrosis rate and necrosis area of the grafted flap.Although there are many therapeutic methods for skin flap ischemia/reperfusion injury,a unified and effective therapeutic method has not yet been developed in the clinic,and the advantages and disadvantages of various therapeutic methods have not yet been compared.Most of the studies remain in the stage of animal experiments,rarely involving clinical observations.Therefore,a lot of research is required in the future to gradually move from animal experiments to the clinic in order to better serve the clinic.

BACKGROUND:Human periodontal ligament stem cells are potential functional cells for periodontal tissue engineering.However,long-term in vitro culture may lead to reduced stemness and replicative senescence of periodontal ligament stem cells,which may impair the therapeutic effect of human periodontal ligament stem cells. OBJECTIVE:To investigate the effect of oxymatrine on the stemness maintenance and osteogenic differentiation of periodontal ligament stem cells in vitro,and to explore the potential mechanism. METHODS:Periodontal ligament stem cells were isolated from human periodontal ligament tissues by tissue explant enzyme digestion and cultured.The surface markers of mesenchymal cells were identified by flow cytometry.Periodontal ligament stem cells were incubated with 0,2.5,5,and 10 μg/mL oxymatrine.The effect of oxymatrine on the proliferation activity of periodontal ligament stem cells was detected by CCK8 assay.The appropriate drug concentration for subsequent experiments was screened.Western blot assay was used to detect the expression of stem cell non-specific proteins SOX2 and OCT4 in periodontal ligament stem cells.qRT-PCR and western blot assay were used to detect the expression levels of related osteogenic genes and proteins in periodontal ligament stem cells. RESULTS AND CONCLUSION:(1)The results of CCK8 assay showed that 2.5 μg/mL oxymatrine significantly enhanced the proliferative activity of periodontal stem cells,and the subsequent experiment selected 2.5 μg/mL oxymatrine to intervene.(2)Compared with the blank control group,the protein expression level of SOX2,a stem marker of periodontal ligament stem cells in the oxymatrine group did not change significantly(P>0.05),and the expression of OCT4 was significantly up-regulated(P<0.05).(3)Compared with the osteogenic induction group,the osteogenic genes ALP,RUNX2 mRNA expression and their osteogenic associated protein ALP protein expression of periodontal ligament stem cells were significantly down-regulated in the oxymatrine+osteogenic induction group(P<0.05).(4)The oxymatrine up-regulated the expression of stemness markers of periodontal ligament stem cells and inhibited the bone differentiation of periodontal ligament stem cells,and the results of high-throughput sequencing showed that it may be associated with WNT2,WNT16,COMP,and BMP6.

Male infertility can result from impaired sperm motility caused by multiple morphological abnormalities of the flagella (MMAF). Distinct projections encircling the central microtubules of the spermatozoal axoneme play pivotal roles in flagellar bending and spermatozoal movement. Mammalian sperm-associated antigen 17 ( SPAG17 ) encodes a conserved axonemal protein of cilia and flagella, forming part of the C1a projection of the central apparatus, with functions related to ciliary/flagellar motility, skeletal growth, and male fertility. This study investigated two novel homozygous SPAG17 mutations (M1: NM_206996.2, c.829+1G>T, p.Asp212_Glu276del; and M2: c.2120del, p.Leu707*) identified in four infertile patients from two consanguineous Pakistani families. These patients displayed the MMAF phenotype confirmed by Papanicolaou staining and scanning electron microscopy assays of spermatozoa. Quantitative real-time polymerase chain reaction (PCR) of patients' spermatozoa also revealed a significant decrease in SPAG17 mRNA expression, and immunofluorescence staining showed the absence of SPAG17 protein signals along the flagella. However, no apparent ciliary-related symptoms or skeletal malformations were observed in the chest X-rays of any of the patients. Transmission electron microscopy of axoneme cross-sections from the patients showed incomplete C1a projection and a higher frequency of missing microtubule doublets 1 and 9 compared with those from fertile controls. Immunofluorescence staining and Western blot analyses of spermatogenesis-associated protein 17 (SPATA17), a component of the C1a projection, and sperm-associated antigen 6 (SPAG6), a marker of the spring layer, revealed disrupted expression of both proteins in the patients' spermatozoa. Altogether, these findings demonstrated that SPAG17 maintains the integrity of spermatozoal flagellar axoneme, expanding the phenotypic spectrum of SPAG17 mutations in humans.
Humans ; Male ; Infertility, Male/pathology* ; Sperm Tail/ultrastructure* ; Homozygote ; Microtubule-Associated Proteins/genetics* ; Axoneme/genetics* ; Spermatozoa/ultrastructure* ; Adult ; Mutation ; Sperm Motility/genetics* ; Pedigree ; Microtubules ; Microtubule Proteins/genetics*

OBJECTIVES: To investigate the molecular epidemiology of children with phenylketonuria (PKU) in Gansu, China, providing foundational data for intervention strategies. METHODS: A retrospective analysis was conducted on 1 159 PKU families who attended Gansu Provincial Maternity and Child Care Hospital from January 2012 to December 2024. Sanger sequencing, multiplex ligation-dependent probe amplification, whole exome sequencing, and deep intronic variant analysis were used to analyze the PAH gene. RESULTS: For the 1 159 children with PKU, 2 295 variants were identified in 2 318 alleles, resulting in a detection rate of 99.01%. The detection rates were 100% (914/914) in 457 classic PKU families, 99.45% (907/912) in 456 mild PKU families, and 96.34% (474/492) in 246 mild hyperphenylalaninemia families. The 2 295 variants detected comprised 208 distinct mutation types, among which c.728G>A (14.95%, 343/2 295) had the highest frequency, followed by c.611A>G (4.88%, 112/2 295) and c.721C>T (4.79%, 110/2 295). The cumulative frequency of the top 23 hotspot variants reached 70.28% (1 613/2 295), and most variant alleles were detected in exon 7 (29.19%, 670/2 295). CONCLUSIONS Deep intronic variant analysis of the PAH gene can improve the genetic diagnostic rate of PKU. The development of targeted detection kits for PAH hotspot variants may enable precision screening programs and enhance preventive strategies for PKU.
Humans ; Phenylketonurias/epidemiology* ; Female ; Male ; Retrospective Studies ; Phenylalanine Hydroxylase/genetics* ; Mutation ; Child, Preschool ; China/epidemiology* ; Child ; Infant

OBJECTIVES: To study the effect of prophylactic phenytoin (PHT) or levetiracetam (LEV) on busulfan (BU) blood concentration in children undergoing hematopoietic stem cell transplantation. METHODS: Pediatric patients conditioned with BU plus cyclophosphamide and fludarabine at the First People's Hospital of Chenzhou from September 2023 to February 2025 were retrospectively included. Patients were grouped by prophylactic antiepileptic regimen into PHT (n=24) and LEV (n=26). BU blood concentrations at the end of infusion (0 hour) and at 1, 2, and 4 hours post-infusion were compared between groups. RESULTS: At 0 hour post-infusion, BU blood concentrations did not differ significantly between groups (P>0.05). At 1, 2, and 4 hours post-infusion, BU blood concentrations were higher in the LEV group than in the PHT group (P<0.05). The area under the concentration-time curve from 0 to ∞ (AUC_0-∞) was greater in the LEV group (P<0.001), and the attainment rate of AUC_0-∞ was higher in the LEV group than in the PHT group (73% vs 21%, P<0.001). No significant differences were observed between groups in time to hematopoietic engraftment or in the incidence of BU-related adverse drug reactions (P>0.05). CONCLUSIONS Compared with PHT, LEV prophylaxis is associated with higher BU blood concentration and a higher AUC_0-∞ attainment rate. There is no observed difference in BU efficacy or safety between PHT and LEV.
Humans ; Levetiracetam/therapeutic use* ; Busulfan/pharmacokinetics* ; Hematopoietic Stem Cell Transplantation ; Male ; Female ; Child ; Child, Preschool ; Phenytoin/pharmacology* ; Infant ; Retrospective Studies ; Anticonvulsants/pharmacology* ; Adolescent

OBJECTIVE: To investigate the effects and underlying mechanism of ionizing radiation on the adipogenic of mesenchymal stem cells (MSCs). METHODS: Mouse MSCs were cultured in vitro and treated with 2 Gy and 6 Gy radiation with ⁶⁰Co, and the radiation dose rate was 0.98 Gy/min. Bulk RNA-seq was performed on control and irradiated MSCs. The changes of adipogenic differentiation and oxidative stress pathways of MSC were revealed by bioinformatics analysis. Oil Red O staining was used to detect the adipogenic differentiation ability of MSCs in vitro, and real-time fluorescence quantitative PCR (qPCR) was used to detect the expression differences of key regulatory factors Cebpa, Lpl and Pparg after radiation treatment. At the same time, qPCR and Western blot were used to detect the effect of inhibition of Nrf2, a key factor of antioxidant stress pathway, on the expression of key regulatory factors of adipogenesis. Moreover, the species conservation of the irradiation response of human bone marrow MSCs and mouse MSC was determined by qPCR. RESULTS: Bulk RNA-seq suggested that ionizing radiation promotes adipogenic differentiation of MSCs and up-regulation of oxidative stress-related genes and pathways. The results of Oil Red O staining and qPCR showed that ionizing radiation promoted the adipogenesis of MSCs, with high expression of Cebpa, Lpl and Pparg, as well as oxidative stress-related gene Nrf2. Nrf2 pathway inhibitors could further enhance the adipogenesis of MSCs in bone marrow after radiation. Notably, the similar regulation of oxidative pathways and enhanced adipogenesis post irradiation were observed in human bone marrow MSCs. In addition, irradiation exposure led to up-regulated mRNA expression of interleukin-6 and down-regulated mRNA expression of colony stimulating factor 2 in human bone marrow MSCs. CONCLUSION Ionizing radiation promotes adipogenesis of MSCs in mice, and oxidative stress pathway participates in this effect, blocking Nrf2 further promotes the adipogenesis of MSCs. Additionally, irradiation activates oxidative pathways and promotes adipogenic differentiation of human bone marrow MSCs.
Mesenchymal Stem Cells/cytology* ; Oxidative Stress/radiation effects* ; Animals ; Adipogenesis/radiation effects* ; Mice ; Radiation, Ionizing ; Cell Differentiation/radiation effects* ; Humans ; NF-E2-Related Factor 2/metabolism* ; PPAR gamma ; Cells, Cultured

OBJECTIVE: To explore the clinical characteristics, therapeutic responses and prognostic features of E2A-PBX1 fusion gene for childhood acute lymphoblastic leukemia (ALL). METHODS: A total of 837 pediatric patients with ALL who were initially diagnosed in our hospital from July 2010 to November 2017 were retrospectively analyzed, 48 children with positive E2A-PBX1 fusion gene were detected by the real-time quantitative PCR techniques and their data were retrospectively collected for analysis. RESULTS: Among 48 cases with positive E2A-PBX1 fusion gene, there were 26 males and 22 females, with onset ages ranging from 9 months to 13 years old. There were 2 cases (4.2%) in the low-risk group, 32 cases (66.7%) in the intermediate-risk group, and 14 cases (29.1%) in the high-risk group at initial diagnosis. The white blood cell (WBC) counts of 25 cases (53.2%) at initial diagnosis were <50×10⁹/L, 11 cases (23.4%) were (50-100)×10⁹/L, and 11 cases (23.4%) ≥100×10⁹/L. The main immunophenotype was common-B ALL (44 cases, 91.7%). Other leukemia fusion genes such as BCR-ABL1, MLL-AF4, and TEL-AML1 were not observed in this cohort of patients. All patients received the treatment of NPCLC-ALL2008 protocol, and 5 cases (10.4%) occurred poor prednisone response. All the 48 cases achieved complete remission (CR) after the induction treatments. The last follow-up date was April 30, 2023. A total of 5 children relapsed, including 1 case with intermediate risk and 4 cases with high risk. The recurrence rate in the high-risk group was significantly higher than that in the intermediate- and low-risk groups (both P < 0.05). Most relapsed children had elevated WBC counts at initial diagnosis. Among them, WBC counts ≥100×10⁹/L was observed in 4 cases. The recurrence rate among children with WBC counts ≥100×10⁹/L was significantly higher than that with WBC counts <100×10⁹/L (P < 0.01). Four deaths occurred in this cohort, of which 3 died of leukemia recurrence. The 10-year event-free survival rate and 10-year overall survival rate of the 48 children with positive E2A-PBX1 fusion gene were 87.5%±4.8% and 91.7%±4.0%, respectively. CONCLUSION In ALL children with positive E2A-PBX1 fusion gene, those with elevated WBC counts and high risk stratification at initial diagnosis are more likely to experience recurrence. Recurrence is the main cause of death in this group. It is suggested that such kind of children receive more intensive chemotherapy or undergo hematopoietic stem cell transplantation as early as possible to further improve prognosis.
Humans ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis* ; Oncogene Proteins, Fusion/genetics* ; Prognosis ; Child ; Male ; Female ; Child, Preschool ; Adolescent ; Retrospective Studies ; Infant ; Homeodomain Proteins