ObjectiveTranscranial magneto-acoustic stimulation (TMAS) is an emerging non-invasive neuromodulation technique that may provide a novel non-pharmacological intervention strategy for Parkinson's disease (PD). PD is characterized by the progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc), leading to motor impairments such as bradykinesia, tremor, and rigidity. Increasing evidence indicates that mitochondrial dysfunction and impaired mitochondrial quality control are central mechanisms underlying dopaminergic neuronal loss. In particular, abnormalities in mitophagy and mitochondrial fission-fusion balance contribute substantially to oxidative stress, energy metabolic failure, and neuronal injury. At present, most clinical treatments for PD mainly alleviate symptoms but do not effectively halt disease progression. Therefore, exploring new interventions targeting the core pathological mechanisms is of considerable significance. This study aims to investigate whether TMAS can improve neural damage and motor dysfunction in PD mice by regulating mitophagy and the fission/fusion dynamic balance, thereby providing theoretical and experimental support for its application in PD treatment. MethodsMale C57BL/6 mice were used in this study. A PD model was established by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) for 7 consecutive days. After model induction, mice in the intervention group received TMAS once daily for 14 consecutive days, whereas the corresponding control group received sham stimulation. The stimulation target was positioned over the primary motor cortex (M1). Motor performance was evaluated using the pole test and the open-field test. To verify the activation effect of TMAS on the target cortical region, c-Fos immunohistochemistry was performed in the M1. To assess nigral dopaminergic neuronal injury, tyrosine hydroxylase (TH) immunohistochemistry was used to quantify TH-positive neurons in the SNc. Mitochondrial function was evaluated by measuring reactive oxygen species (ROS) levels and adenosine triphosphate (ATP) content in the SNc. Western blot was further performed to determine the expression of mitophagy-related proteins, including PINK1, Parkin, LC3-II, and p62, as well as mitochondrial dynamics-related proteins, including Drp1 and Opa1. ResultsTMAS significantly increased the number of c-Fos-positive cells in M1 (P<0.000 1), indicating effective activation of neurons in the targeted cortical region. Compared with the control group, MPTP-treated mice exhibited marked motor dysfunction, including a significant reduction in total distance traveled in the open-field test (P<0.000 1) and mean speed (P=0.000 1), as well as significant prolongation of turn time and total climbing time in the pole test (P<0.000 1). These behavioral impairments were accompanied by a substantial loss of TH-positive dopaminergic neurons in the SNc, whereas TMAS significantly increased TH-positive neuron survival (P<0.000 1). In parallel, MPTP induced a pronounced increase in ROS levels and a significant reduction in ATP content, indicating severe mitochondrial dysfunction and energy metabolism impairment (P<0.01). TMAS treatment significantly improved motor performance, as reflected by the reversal of MPTP-induced impairment in the open-field and pole tests, and significantly reduced ROS accumulation (P<0.01) while restoring ATP production (P<0.001). At the molecular level, MPTP markedly downregulated PINK1 and Parkin, decreased p62 expression, increased LC3-II accumulation, elevated Drp1 expression, and reduced Opa1 expression, whereas TMAS significantly reversed these abnormalities, suggesting restoration of mitophagy-related mitochondrial quality control and re-establishment of mitochondrial fission-fusion balance. Collectively, these findings indicate that TMAS ameliorates MPTP-induced neurotoxicity and restores mitochondrial homeostasis and energy metabolism. ConclusionTMAS effectively attenuates neural damage and improves motor dysfunction in MPTP-induced PD mice. Its neuroprotective effects are closely associated with multidimensional regulation of the mitochondrial quality control system, including restoration of PINK1/Parkin-mediated mitophagy and rebalancing of Drp1/Opa1-related mitochondrial dynamics. Rather than acting only as a symptomatic neuromodulatory intervention, TMAS may influence a key pathological axis of PD by improving mitochondrial homeostasis in SNc and protecting nigral dopaminergic neurons. These findings provide experimental evidence supporting TMAS as a promising non-invasive physical intervention for PD.

ObjectiveTranscranial magneto-acoustic stimulation (TMAS) is an emerging non-invasive neuromodulation technique that may provide a novel non-pharmacological intervention strategy for Parkinson's disease (PD). PD is characterized by the progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc), leading to motor impairments such as bradykinesia, tremor, and rigidity. Increasing evidence indicates that mitochondrial dysfunction and impaired mitochondrial quality control are central mechanisms underlying dopaminergic neuronal loss. In particular, abnormalities in mitophagy and mitochondrial fission-fusion balance contribute substantially to oxidative stress, energy metabolic failure, and neuronal injury. At present, most clinical treatments for PD mainly alleviate symptoms but do not effectively halt disease progression. Therefore, exploring new interventions targeting the core pathological mechanisms is of considerable significance. This study aims to investigate whether TMAS can improve neural damage and motor dysfunction in PD mice by regulating mitophagy and the fission/fusion dynamic balance, thereby providing theoretical and experimental support for its application in PD treatment. MethodsMale C57BL/6 mice were used in this study. A PD model was established by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) for 7 consecutive days. After model induction, mice in the intervention group received TMAS once daily for 14 consecutive days, whereas the corresponding control group received sham stimulation. The stimulation target was positioned over the primary motor cortex (M1). Motor performance was evaluated using the pole test and the open-field test. To verify the activation effect of TMAS on the target cortical region, c-Fos immunohistochemistry was performed in the M1. To assess nigral dopaminergic neuronal injury, tyrosine hydroxylase (TH) immunohistochemistry was used to quantify TH-positive neurons in the SNc. Mitochondrial function was evaluated by measuring reactive oxygen species (ROS) levels and adenosine triphosphate (ATP) content in the SNc. Western blot was further performed to determine the expression of mitophagy-related proteins, including PINK1, Parkin, LC3-II, and p62, as well as mitochondrial dynamics-related proteins, including Drp1 and Opa1. ResultsTMAS significantly increased the number of c-Fos-positive cells in M1 (P<0.000 1), indicating effective activation of neurons in the targeted cortical region. Compared with the control group, MPTP-treated mice exhibited marked motor dysfunction, including a significant reduction in total distance traveled in the open-field test (P<0.000 1) and mean speed (P=0.000 1), as well as significant prolongation of turn time and total climbing time in the pole test (P<0.000 1). These behavioral impairments were accompanied by a substantial loss of TH-positive dopaminergic neurons in the SNc, whereas TMAS significantly increased TH-positive neuron survival (P<0.000 1). In parallel, MPTP induced a pronounced increase in ROS levels and a significant reduction in ATP content, indicating severe mitochondrial dysfunction and energy metabolism impairment (P<0.01). TMAS treatment significantly improved motor performance, as reflected by the reversal of MPTP-induced impairment in the open-field and pole tests, and significantly reduced ROS accumulation (P<0.01) while restoring ATP production (P<0.001). At the molecular level, MPTP markedly downregulated PINK1 and Parkin, decreased p62 expression, increased LC3-II accumulation, elevated Drp1 expression, and reduced Opa1 expression, whereas TMAS significantly reversed these abnormalities, suggesting restoration of mitophagy-related mitochondrial quality control and re-establishment of mitochondrial fission-fusion balance. Collectively, these findings indicate that TMAS ameliorates MPTP-induced neurotoxicity and restores mitochondrial homeostasis and energy metabolism. ConclusionTMAS effectively attenuates neural damage and improves motor dysfunction in MPTP-induced PD mice. Its neuroprotective effects are closely associated with multidimensional regulation of the mitochondrial quality control system, including restoration of PINK1/Parkin-mediated mitophagy and rebalancing of Drp1/Opa1-related mitochondrial dynamics. Rather than acting only as a symptomatic neuromodulatory intervention, TMAS may influence a key pathological axis of PD by improving mitochondrial homeostasis in SNc and protecting nigral dopaminergic neurons. These findings provide experimental evidence supporting TMAS as a promising non-invasive physical intervention for PD.

Objective:To identify strain-specific features of Klebsiella pneumoniae by analyzing metagenomics next generation sequencing (mNGS) data, thereby expanding the downstream applications of mNGS. Methods:The sequences of K.pneumoniae strains were organized from both the self-built database of the long-term multi-center research cohort in China established by the Peking University People′s Hospital from 2009 to 2020 (with 2 345 sequences) and the public databases (with 19 648 sequences). The existing large-scale databases were compressed, and a set of strains representative of clonal groups were screened. A strain genome information library was constructed based on k-mer features, and the most matching representative sequences in the database were searched for the raw mNGS data. The search results of the self-built library and public library were merged and optimized to update the prediction of antimicrobial-resistance characteristics and avoid the impact of uneven data distribution on the results. A total of 314 clinical samples from patients with K.pneumoniae detected by mNGS in the Clinical Microbiology Laboratory of Peking University People′s Hospital from 2022 to 2024 were retrospectively collected, and 101 samples with positive clinical culture results were selected to validate the prediction results. The antimicrobial-resistance phenotypes were verified by clinical antimicrobial susceptibility test results. Whole-genome sequencing was performed on the culture strains of 14 samples randomly selected using random numbers to verify the genotypes. Single nucleotide polymorphism distance analysis was used to verify the occurrence of outbreak events. The χ2 test and Mann-Whitney U test were used for statistical analysis. Results:A representative strain sequence k-mer feature library containing self-built and public sub-libraries was constructed. The library construction required only about 1 hour with <3 GB storage, with a high compression ratio and low update cost. Using k-mer-based analysis, mNGS data achieved precise strain characterization within 4 minutes and and <5 GB memory occupation. There was a significant difference in the antimicrobial-resistance rates to more than half of the antibiotics between the self-built database (90.8%, 2 130/2 345) and the public database (22.7%, 4 457/19 648) ( χ2=4 634.1, P<0.001). After optimizing the search results, the mean category agreement, sensitivity, and specificity of the prediction for eight antibiotics reached 84.8% (323/381), 78.9% (131/166), and 91.2% (196/215), respectively. The target genotypes were successfully detected in 10 out of 12 samples, and two outbreak events (2 samples per event) were successfully identified. Conclusions:An independent analysis process adapted to the needs of identifying the features of K. pneumoniae strains in mNGS data was developed. This process requires minimal computational resources and processing time and can directly achieve the simultaneous analysis of the antimicrobial-resistance phenotypes of K. pneumoniae at the strain level and their corresponding genomic characteristic profiles based on the raw mNGS reads.

[This corrects the article DOI: 10.1016/j.apsb.2022.05.019.].

Recent studies have indicated that the expression of ubiquitin-specific protease 51 (USP51), a novel deubiquitinating enzyme (DUB) that mediates protein degradation as part of the ubiquitin‒proteasome system (UPS), is associated with tumor progression and therapeutic resistance in multiple malignancies. However, the underlying mechanisms and signaling networks involved in USP51-mediated regulation of malignant phenotypes remain largely unknown. The present study provides evidence of USP51's functions as the prominent DUB in chemoresistant triple-negative breast cancer (TNBC) cells. At the molecular level, ectopic expression of USP51 stabilized the 78 kDa Glucose-Regulated Protein (GRP78) protein through deubiquitination, thereby increasing its expression and localization on the cell surface. Furthermore, the upregulation of cell surface GRP78 increased the activity of ATP binding cassette subfamily B member 1 (ABCB1), the main efflux pump of doxorubicin (DOX), ultimately decreasing its accumulation in TNBC cells and promoting the development of drug resistance both in vitro and in vivo. Clinically, we found significant correlations among USP51, GRP78, and ABCB1 expression in TNBC patients with chemoresistance. Elevated USP51, GRP78, and ABCB1 levels were also strongly associated with a poor patient prognosis. Importantly, we revealed an alternative intervention for specific pharmacological targeting of USP51 for TNBC cell chemosensitization. In conclusion, these findings collectively indicate that the USP51/GRP78/ABCB1 network is a key contributor to the malignant progression and chemotherapeutic resistance of TNBC cells, underscoring the pivotal role of USP51 as a novel therapeutic target for cancer management.

Neuropathic pain, often featuring allodynia, imposes significant physical and psychological burdens on patients, with limited treatments due to unclear central mechanisms. Addressing this challenge remains a crucial unsolved issue in pain medicine. Our previous study, using protein kinase C gamma (PKCγ)-tdTomato mice, highlights the spinal feedforward inhibitory circuit involving PKCγ neurons in gating neuropathic allodynia. However, the regulatory mechanisms governing this circuit necessitate further elucidation. We used diverse transgenic mice and advanced techniques to uncover the regulatory role of the descending serotonin (5-HT) facilitation system on spinal PKCγ neurons. Our findings revealed that 5-HT neurons from the rostral ventromedial medulla hyperpolarize spinal inhibitory interneurons via 5-HT_2C receptors, disinhibiting the feedforward inhibitory circuit involving PKCγ neurons and exacerbating allodynia. Inhibiting spinal 5-HT_2C receptors restored the feedforward inhibitory circuit, effectively preventing neuropathic allodynia. These insights offer promising therapeutic targets for neuropathic allodynia management, emphasizing the potential of spinal 5-HT_2C receptors as a novel avenue for intervention.
Animals ; Neuralgia/physiopathology* ; Protein Kinase C/metabolism* ; Receptor, Serotonin, 5-HT2C/metabolism* ; Hyperalgesia/physiopathology* ; Mice, Transgenic ; Mice ; Spinal Cord/metabolism* ; Serotonin/metabolism* ; Male ; Neurons/metabolism* ; Mice, Inbred C57BL

The prelimbic cortex (PL) plays a critical role in processing both the sensory and affective components of pain. However, the underlying molecular mechanisms remain poorly understood. In this study, we observed a reduction in hyperpolarization-activated cation current (I_h) in layer V pyramidal neurons of the contralateral PL in a mouse model of spared nerve injury (SNI). The expression of hyperpolarization-activated cyclic nucleotide-gated 2 (HCN2) channels was also decreased in the contralateral PL. Conversely, microinjection of fisetin, a partial agonist of HCN2, produced both analgesic and anxiolytic effects. Additionally, we found that cyclin-dependent kinase 5 (CDK5) was activated in the contralateral PL, where it formed a complex with HCN2 and phosphorylated its C-terminus. Knockdown of CDK5 restored HCN2 expression and alleviated both pain hypersensitivity and anxiety-like behaviors. Collectively, these results indicate that CDK5-mediated dysfunction of HCN2 in the PL underlies nerve injury-induced mechanical hypersensitivity and anxiety.
Animals ; Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels/metabolism* ; Hyperalgesia/metabolism* ; Cyclin-Dependent Kinase 5/metabolism* ; Neuralgia/metabolism* ; Male ; Anxiety/metabolism* ; Mice ; Potassium Channels/metabolism* ; Mice, Inbred C57BL ; Disease Models, Animal ; Pyramidal Cells/metabolism*

Objective:To investigate the efficacy and safety of intravesical injections of botulinum toxin A (BTX-A) for the treatment of pediatric refractory urinary frequency and incontinence (UFI), and to analyze the factors predicting the therapeutic effect of BTX-A injections.Methods:A retrospective case series study was made on 35 children with UFI [(12.3±4.2) years old], including 13 males (37.1%) and 22 females (62.9%), treated in the First Affiliated Hospital of Zhengzhou University from January 2021 to March 2024.Urotherapy and drug treatments were ineffective in all children, who then received intravesical injections of BTX-A.The urodynamic study (UDS) was performed 1 week before treatment and 3 months after treatment, and the Overactive Bladder Symptom Score (OABSS) and Incontinence Quality of Life (I-QOL) were collected.Perioperative and postoperative adverse events were also recorded.A global response assessment (GRA) score of ≥2 at 3 months postoperatively was defined as effective treatment.According to the postoperative GRA score, the patients were divided into effective and ineffective groups to explore the predictive factors affecting the outcome of BTX-A treatment, such as age, gender, preoperative urodynamic parameters, and the types of urinary incontinence. t-test was used to compare quantitative data such as age, UDS parameters, OABSS, and I-QOL scores.The comparison of count data such as gender and urinary incontinence types was conducted using Fisher′s exact test. Results:The bladder compliance, bladder capacity ratio, OABSS and I-QOL scores of patients significantly improved after BTX-A injection (all P<0.05).The 77.1% (27/35) of the patients were satisfied with BTX-A treatment effects.The main adverse event during the follow-up was a temporary increase in postvoid residual urine after injecting BTX-A (7 cases), which was alleviated by the Creade action or clean intermittent catheterization.There was significant difference in age [(13.00±4.32) years vs.(10.00±2.67) years] and preoperative bladder compliance [(11.21±5.74) mL/cmH 2O vs.(5.13±2.42) mL/cmH 2O] between effective (27 cases) and ineffective groups (8 cases) ( t=2.383, 2.899, all P<0.05).The differences in preoperative bladder capacity ratio, maximum filling detrusor pressure, postvoid residual urine, voiding efficiency, gender, and the types of urinary incontinence were not statistically significant between the two groups (all P>0.05). Conclusions:Intravesical injection of BTX-A is a safe and effective treatment for children with refractory UFI.A young age and poor bladder compliance at treatment are associated with poor prognosis of BTX-A treatment.

Objective To explore the role of miR-429 in synovial mesenchymal stem cell-derived exosomes(SMSC-Exos)in repairing cartilage damage in temporomandibular joint osteoarthritis(TMJ OA)by extracting SMSC-Exos from human synovial tissue and screening differentially expressed microRNA(miRNA)through transcriptome sequencing.Methods Human synovial tissues were obtained from 6 patients who underwent surgery at the First Medical Center of the Chinese PLA General Hospital from June to December 2023,including 3 patients with osteoarthritis(OA group)and 3 control patients(control group),all of whom were male.SMSC-Exos were extracted from the synovial tissues for miRNA sequencing and differential expression analysis.Further,Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were performed on the target genes of differentially expressed miRNA to identify key functional miRNA and construct miRNA-target gene regulatory networks and protein-protein interaction(PPI)networks of target genes.An in vitro model of rabbit condylar cartilage cell inflammatory microenvironment induced by interleukin-1β(IL-1β)was established,with the control group cultured in DMEM/F12 basic medium and the inflammation-induced group cultured in DMEM/F12 basic medium containing 10 ng/ml IL-1β.RT-qPCR was used to detect the effects of overexpressed target miRNA on the mRNA expression levels of cartilage phenotype factors such as type Ⅱ collagen α1 chain(Col2a1),aggrecan(Acan),as well as inflammatory factors including a disintegrin and metalloproteinase with thrombospondin motifs 5(Adamts5)and cyclooxygenase-2(Cox-2).Results(1)SMSC-Exos were successfully isolated,cultured,and identified.(2)miRNA sequencing of SMSC-Exos from OA and control groups revealed 16 differentially expressed miRNAs(|log2FC|>2,P<0.05).Compared with control group,7 miRNAs were up-regulated and 9 were down-regulated in OA group.GO and KEGG analysis indicated that the target genes of miR-429 were mainly involved in development process,anatomical structure development,system development,cell development and differentiation,and were enriched in inflammation-related pathways such as mitogen-activated protein kinase(MAPK)and phosphatidylinositol 3-kinase-protein kinase B(PI3K-Akt).(3)Functional validation of miR-429 in the rabbit condylar cartilage cell inflammatory model showed that overexpression of miR-429 increased the mRNA expression levels of Col2a1 and Acan(P<0.05)and decreased the mRNA expression levels of Adamts5 and Cox-2(P<0.05)in the inflammation-induced group.Conclusions miRNA sequencing of SMSC-Exos isolated and identified from human synovial tissues reveals a specific miRNA expression profile in OA patients,with miR-429 significantly down-regulated.Functional validation demonstrates that overexpression of miR-429 has reparative and anti-inflammatory effects on condylar cartilage cells in an inflammatory microenvironment.

OBJECTIVE: To investigate the variability of bone metabolism levels among different populations and its association with knee osteoarthritis (KOA) pain. METHODS: A total of 50 people (control group) who participated in physical examination from January 2023 to June 2023 were selected, including 26 males and 24 females, wtih a mean aged of (52.14±9.04) years old ranging 41 to 65 years old. The other 50 patients with knee osteoarthritis(case group) who attended the outpatient clinic of the Orthopedics and Traumatology Department in the same time period, including 19 males and 31 females, with a mean age of (53.60±7.76) years old ranging 40 to 65 years. The two groups of Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC) and bone metabolism markers, such as 25-hydroxy-cholecalciferol[25(OH)D], β-isomerized typeⅠcollagen C-telopeptide breakdown products (β-CTX), total typeⅠprocollagen N-terminal propeptide (t-PINP), osteocalcin (OC), parathormone (PTH) levels were compared. Pearson correlation analysis was used to compare the correlation between two groups of bone metabolism related markers and WOMAC. RESULTS: The WOMAC score of the case group (39.90±2.34) was higher than that of the control group (3.60±0.57), with significant difference (P<0.05). There was no significant difference between the two groups of 25 (OH)D, β-CTX and PTH (P>0.05). The t-PINP and OC of the case group were (62.90±52.40) and (19.88±10.15) ng·ml-1, respectively, and those of the control group were (38.86±10.82) and (14.90±3.62) ng·ml^-1, respectively;the t-PINP and OC of the case group were higher than those of the control group, with significant difference (P<0.05). Pearson correlation analysis showed that t-PINP was positively correlated with WOMAC pain score in the case group (r²=0.045, P<0.01). CONCLUSION Bone metabolism levels in the serum of patients with knee osteoarthritis are different from those of healthy people, and the difference between OC and t-PINP is the most obvious, and the concentration of t-PINP levels is positively correlated with pain symptoms in patients with KOA. However, the specific mechanism of correlation between the bone metabolism levels of patients with KOA and their pain symptoms needs to be further elucidated by basic experimental research as well as by enlarging the samples.
Humans ; Female ; Male ; Middle Aged ; Osteoarthritis, Knee/metabolism* ; Aged ; Adult ; Bone and Bones/metabolism* ; Pain/etiology* ; Biomarkers/metabolism*