Nicotinic acetylcholine receptors (nAChRs) are pentameric ligand-gated ion channels (pLGICs) that mediate rapid cholinergic synaptic transmission throughout the central and peripheral nervous systems. These receptors are integral to neuromuscular junction signaling, autonomic regulation, cognitive learning, reward-related behavior, and neuroplasticity. The nAChR family exhibits remarkable functional diversity through combinatorial assembly of seventeen identified subunits (α1-α10, β1-β4, γ, δ, and ε). Among these, the α9 subunit occupies a distinctive phylogenetic position, exhibiting greater sequence divergence from other neuronal α subunits and possessing unique biochemical properties that distinguish it from all other family members. α9 can form homopentamers and also co-assemble with the α10 subunit to form functional heteropentamers, primarily in (α9)₂(α10)₃ and (α9)₃(α10)₂ stoichiometries. This dual assembly strategy generates functional heterogeneity, as distinct subunit compositions confer differential ion permeation, ligand sensitivity, and desensitization kinetics. The structural determinants governing this stoichiometric variability remain incompletely resolved, representing a critical gap in our mechanistic understanding. Unlike most other nAChR subtypes, traditional agonists of nAChRs (such as nicotine) elicit virtually no agonistic effect on α9* nAChRs (α9-containing receptors, including α9 homopentamers and α9α10 heteropentamers). This pharmacological divergence reflects structural differences within the orthosteric site, particularly in regions at complementary subunit interfaces. As cation-selective channels, α9* nAChRs exhibit high permeability to Ca²⁺. In cochlear outer hair cells, α9α10 nAChRs mediate cholinergic efferent modulation by the medial olivocochlear (MOC) bundle. Acetylcholine-evoked Ca²⁺ influx activates functionally coupled SK2 potassium channels, generating net hyperpolarization that dampens electromechanical amplification through a tightly constrained signaling microdomain. This Ca²⁺-dependent excitatory-to-inhibitory conversion exemplifies sophisticated sensory gain control, and its disruption contributes to noise-induced hearing loss, age-related hearing loss, and tinnitus. Beyond canonical ionotropic signaling, α9* nAChR engages metabotropic transduction pathways. In macrophages, receptor activation modulates cytokine production and inflammatory responses. In keratinocytes, it regulates wound healing by modulating cell migration and differentiation. In dorsal root ganglion sensory neurons, α9* signaling contributes to nociceptive processing and inflammatory hyperalgesia. This functional pleiotropy, spanning both ionotropic signaling and metabotropic transduction, positions α9* nAChR as an exemplary model for investigating signal polymorphism within the pLGIC superfamily. Pathophysiologically, α9* nAChR dysfunction is implicated across multiple organ systems. In the auditory system, disruption of α9α10 nAChR-mediated MOC efferent feedback impairs cochlear gain control, predisposing to noise-induced synaptopathy and age-related hearing loss. In immune cells, dysfunctional α9* nAChR signaling disrupts cholinergic anti-inflammatory pathway activity, exacerbating pro-inflammatory responses. In the peripheral sensory system, aberrant α9* nAChR signaling has been implicated in neuropathic and inflammatory pain states. In skin, impaired receptor function compromises keratinocyte migration and re-epithelialization through disrupted signaling pathways, leading to chronic wound healing defects and inflammation. These pathophysiological associations have catalyzed pharmacological interest, yielding promising chemical entities including α‑conotoxins, small-molecule antagonists/agonists, and allosteric modulators.α-Conotoxin peptides, in particular, demonstrate remarkable subunit selectivity and potent antinociceptive effects in preclinical pain models. However, therapeutic translation faces substantial challenges: the broad tissue distribution of α9* nAChR risks on-target adverse effects in non-target organs; pronounced species differences between rodent and human receptors complicate preclinical validation; and the complexity of ionotropic-metabotropic signaling crosstalk demands pharmacological strategies that extend beyond conventional orthosteric agonism or antagonism. Looking forward, integrating cryo-electron microscopy of full-length receptors in distinct conformational states with single-channel electrophysiology and systems-level circuit analysis promises to illuminate the molecular mechanisms governing α9* nAChR function and regulation. The development of signal pathway-biased ligands and tissue-selective delivery strategies may ultimately harness the therapeutic potential of this receptor while mitigating safety liabilities. As a paradigm for understanding pLGIC signaling diversification, α9* nAChR research will continue to inform broader questions regarding ion channel evolution, allosteric regulation, and pathophysiological mechanisms of chronic pain and autoimmune inflammatory diseases.

ObjectiveAs a second messenger in intracellular signal transduction, Ca²⁺ plays an important role in cell migration. Previous studies have demonstrated that extracellular Ca²⁺ influx can promote electric field-guided cell migration, known as electrotaxis. However, the effect of intracellular Ca²⁺ flow on electrotaxis is unclear. Therefore, in this study, we investigate the effect of Ca²⁺ flux on the electrotaxis of Dictyostelium discoideum. MethodsThe electrotaxis of Dictyostelium discoideum was investigated by applying a direct current (DC) electric field. Cell migration was recorded using a real-time imaging system. Calcium channel inhibitors, the extracellular Ca²⁺ chelator EGTA, Ca²⁺-free DB buffer, and caffeine were applied to investigate the impact of intra- and extracellular Ca²⁺ flow on electrotaxis. The involvement of G proteins and ERK2 in directed cell migration mediated by endoplasmic reticulum Ca²⁺ release was explored using mutants. ResultsDictyostelium discoideum migrated toward the cathode in the electric field in a voltage-dependent manner. The intracellular Ca²⁺ concentration of the cells was significantly increased in the electric field. Inhibition of both extracellular Ca²⁺ influx and intracellular Ca²⁺ release suppressed cell electrotaxis migration. Inhibition of endoplasmic reticulum Ca²⁺ release induced by caffeine significantly impaired the electrotaxis of Dictyostelium discoideum. Deletion of Gα2, Gβ, Gγ, and Erk2 notably reduced the electrotaxis of the cells. Enhancing Ca²⁺ release mediated by caffeine restored the electrotaxis of the Gα2^-, Gβ ^-, and Erk2^- mutant cells partially or completely, but did not restore electrotaxis in the Gγ^- mutant cells. ConclusionCa²⁺ release from the endoplasmic reticulum regulates electrotaxis migration in Dictyostelium discoideum and is involved in the regulation of cell electrotaxis by G proteins and ERK2.

Objective To investigate the comparative neuroprotective effects of human umbilical cord mesenchymal stem cells(hUC-MSCs-Exos)administered via different routes on hypoxic ischemic brain damage(HIBD)in neonatal mice.Methods Healthy one-week-old SPF-grade BALB/c mice were randomly divided into 4 groups:sham operation group(n=6),model group(n=6),exosome group 1(n=8),exosome group 2(n=8).HIBD was induced using the Rice-Vannucci method.Exosome group 1 and Exosome group 2 were intraperitoneal injection/intranasal drip of phosphate buffer(PBS)100 μl containing 10 μl exosomes within 24 h after successful modeling,respectively.Sham operation and model groups were intraperitoneal injection of PBS 100 μl.On the 7th day after the intervention,neuromotor function was assessed using the horizontal grid test and pole climbing test.On the 2nd day after the evaluation,all mice were killed and their brains were removed by decapitation.HE staining was used to observe the pathological injury of brain tissue,toluidine blue staining was used to observe the survival of neurons in cerebral cortex,and TUNEL staining was used to observe the apoptosis of cerebral cortex cells.Results Compared with sham operation group,model group,exosome group 1 and exosome group 2 exhibited increased hind limb drops in horizontal grid test and climbing scores(P<0.05).No significant difference was found in model group,exosome group 1 and exosome group 2 in these measures(P<0.05).Significant pathology was observed in model group,exosome group 1 and exosome group 2 compared to sham operation group(P<0.05),with significantly reduced damage in exosome group 1 and exosome group 2 compared to model group(P<0.05).Compared with sham operation group,Nissl body count was lower in model group and exosome group 1 and exosome group 2,with a higher count in exosome group 2 compared to exosome group 1(P<0.05).Compared with sham operation group,apoptotic cells were higher in model group and exosome group 1 and exosome group 2,with a significant reduction in exosome group 1 and exosome group 2 compared to model group,and the lowest in exosome group 2(P<0.05).Conclusions hUC-MSCs-Exos can improve the neuronal motor function,promote neuron repair and inhibit apoptosis in HIBD mice.Intranasal administration of hUC-MSCs-Exos is more effective than intraperitoneal administration for reducing neuronal apoptosis in HIBP neonatal mice,offering a convenient and rapid method suitable for clinical application.

ObjectiveDisruption of epithelial layer may instantaneously induce the generation of endogenous electric fields, which was proved to play an important role in guiding the cell migration and promoting wound healing. PIEZO1 is a kind of mechanic sensitive channel, may be regulated by voltage, is proved to involve in chemotactic migration of cells and play an important role in the process of wound healing. In this paper, the role of PIEZO1 and its downstream proteins FAK and integrin β1 in the electric field guided cell migration were investigated by HaCaT cells (human immortalized keratinocyte). MethodsCell migration was tracked by Living Cell Imaging System in directed current (DC) electric field (EF). Inhibitors and RNAi techniques were applied to study the function of PIEZO1 and other related proteins in electric fields. Western blot was used to detect the expression and phosphorylation levels of integrin β1 and FAK in electric field guided migration under EF stimulation. ResultsPiezo1 RNAi as well as Ruthenium red and GsMTx4 treatment all significantly inhibited the electrotaxis of HaCaT cells. Electric field stimulation with GsMTx4 treatment alone increased FAK phosphorylation level and the expression of integrin β1. Electric field promoted the expression level of integrin β1 and the phosphorylation level of FAK. Inhibiting the expression of PIEZO1 by RNAi significantly attenuated the phosphorylation level of FAK under EF stimulation. Inhibition of integrin β1 and FAK by inhibitor significantly decrease the electric field guided cell migration. ConclusionPIEZO1 as well as integrin β1 and FAK are involved in the electric field guided cell migration of HaCaT cells. Electric field signals regulate the expression of integrin β1 and the activation of FAK through PIEZO1-mediated signal pathway to orchestrate cell migration.

Objective To establish antemortem and postmortem injury models in nude mice,observe the morphological changes of the wounds and the changes of the microbial communities in the wounds at different time points after the injury,and analyze the differences between antemortem and postmor-tem wounds.Methods Abdominal injury models were established in 48 BALB/c nude mice,which were classified into antemortem injury,4 h and 72 h postmortem injury groups,and the gross manifesta-tions and histopathological changes were observed on days 1,3,5,8,11 and 15 after injury.The mi-crobial communities in the wounds were analyzed by 16S rRNA sequencing technology.QIIME 2 soft-ware was used to calculate Shannon and Observed species indices.The Kruskal-Wallis test was used to determine statistical differences in α-diversity between groups.Jaccard similarity coefficients were calculated by using R v4.3.0 software and applied to the principal co-ordinates analysis to demonstrate inter-sample differences.Permutational multivariate analysis of variance(PERMANOVA)was used to analyze the differences between groups in the composition of bacterial colonies,and R2 values were calculated.Results On days 8,11 and 15 after injury,the antemortem and postmortem injuries could not be differentiated by morphological examination;the Shannon index and Observed species index were statistically different between the antemortem injury group and the 72 h postmortem injury group;the Jaccard similarity coefficient of the microbial community was statistically different between the an-temortem injury group and the 72 h postmortem injury group.The PERMANOVA R2 value gradually increased with the extension of time(0.22-0.61).Conclusion Through the analysis of the wound mi-crobial community,the microbial composition of wounds at different time points can be identified and compared,which provides a new perspective and method for the differentiation of antemortem injuries from postmortem injuries,with good application prospects.

Objective: Total neoadjuvant therapy has been used to improve tumor responses and prevent distant metastases in patients with locally advanced rectal cancer (LARC). Patients with complete clinical responses (cCR) then have the option of choosing a watch and wait (W&W) strategy and organ preservation. It has recently been shown that hypofractionated radiotherapy has better synergistic effects with PD-1/PD-L1 inhibitors than does conventionally fractionated radiotherapy, increasing the sensitivity of microsatellite stable (MSS) colorectal cancer to immunotherapy. Thus, in this trial we aimed to determine whether total neoadjuvant therapy comprising short-course radiotherapy (SCRT) combined with a PD-1 inhibitor improves the degree of tumor regression in patients with LARC. Methods: TORCH is a prospective, multicenter, randomized, phase II trial (TORCH Registration No. NCT04518280). Patients with LARC (T3-4/N+M0, distance from anus ≤10 cm) are eligible and are randomly assigned to consolidation or induction arms. Those in the consolidation arm receive SCRT (25Gy/5 Fx), followed by six cycles of toripalimab plus capecitabine and oxaliplatin (ToriCAPOX). Those in the induction arm receive two cycles of ToriCAPOX, then undergo SCRT, followed by four cycles of ToriCAPOX. Patients in both groups undergo total mesorectal excision (TME) or can choose a W&W strategy if cCR has been achieved. The primary endpoint is the complete response rate (CR, pathological complete response [pCR] plus continuous cCR for more than 1 year). The secondary endpoints include rates of Grade 3-4 acute adverse effects (AEs) etc. Results: Up to 30 September 2022, 62 patients attending our center were enrolled (Consolidation arm: 34, Induction arm:28). Their median age was 53 (27-69) years. Fifty-nine of them had MSS/pMMR type cancer (95.2%), and only three MSI-H/dMMR. Additionally, 55 patients (88.7%) had Stage III disease. The following important characteristics were distributed as follows: lower location (≤5 cm from anus, 48/62, 77.4%), deeper invasion by primary lesion (cT4 7/62, 11.3%; mesorectal fascia involved 17/62, 27.4%), and high risk of distant metastasis (cN2 26/62, 41.9%; EMVI+ 11/62, 17.7%). All 62 patients completed the SCRT and at least five cycles of ToriCAPOX, 52/62 (83.9%) completing six cycles of ToriCAPOX. Finally, 29 patients achieved cCR (46.8%, 29/62), 18 of whom decided to adopt a W&W strategy. TME was performed on 32 patients. Pathological examination showed 18 had achieved pCR, four TRG 1, and 10 TRG 2-3. The three patients with MSI-H disease all achieved cCR. One of these patients was found to have pCR after surgery whereas the other two adopted a W&W strategy. Thus, the pCR and CR rates were 56.2% (18/32) and 58.1% (36/62), respectively. The TRG 0-1 rate was 68.8% (22/32). The most common non-hematologic AEs were poor appetite (49/60, 81.7%), numbness (49/60, 81.7%), nausea (47/60, 78.3%) and asthenia (43/60, 71.7%); two patients did not complete this survey. The most common hematologic AEs were thrombocytopenia (48/62, 77.4%), anemia (47/62, 75.8%), leukopenia/neutropenia (44/62, 71.0%) and high transaminase (39/62, 62.9%). The main Grade III-IV AE was thrombocytopenia (22/62, 35.5%), with three patients (3/62, 4.8%) having Grade IV thrombocytopenia. No Grade V AEs were noted. Conclusions: SCRT-based total neoadjuvant therapy combined with toripalimab can achieve a surprisingly good CR rate in patients with LARC and thus has the potential to offer new treatment options for organ preservation in patients with MSS and lower-location rectal cancer. Meanwhile, the preliminary findings of a single center show good tolerability, the main Grade III-IV AE being thrombocytopenia. The significant efficacy and long-term prognostic benefit need to be determined by further follow-up.
Humans ; Middle Aged ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Chemoradiotherapy ; Immune Checkpoint Inhibitors/therapeutic use* ; Neoadjuvant Therapy ; Prospective Studies ; Rectal Neoplasms/pathology* ; Thrombocytopenia/drug therapy* ; Treatment Outcome ; Adult ; Aged

Objective: This study aims to investigate the sleep quality of pregnant women in Xuhui District, Shanghai, and the related factors of sleep disturbances during pregnancy. Methods: From February 2019 to February 2021, we used online integrated sleep questionnaire (including PSQI, BQ, ESS, AIS) in Shanghai Jiao Tong University School of Medicine Affiliated Sixth People's Hospital, The International Peace Maternity and Child Health Hospitals of China Welfare Institution, and Shanghai Eighth People's Hospital, to investigate the sleep quality across pregnancy. We also collected maternal physical examination results, childbearing history, sociodemographic, and other clinical data. The prevalences and related factors of various sleep disturbances in pregnant women were analyzed, including insufficient/excessive nighttime sleep, low sleep efficiency, difficulty falling asleep, poor sleep quality, insomnia, daytime sleepiness, and high risk of sleep-disordered breathing (SDB). Results: This study includes 1 898 cases in the first trimester (T1), 3 099 cases in the second trimester (T2), and 1 539 cases in the third trimester (T3). Poor sleep quality (38.6%), daytime sleepiness (mild 41.9%, moderate 17.7%, severe 2.1%), and suspicious insomnia (32.3%) are most prevalent among women in T1 (P<0.01). In comparison, short sleep time (2.7%), long sleep time (8.6%), difficulty falling asleep (12.2%), poor sleep efficiency (35.4%), very poor sleep quality (6.7%), clinical insomnia (21.8%), and high-risk SDB (6.4%) are most prevalent among women in T3 (P<0.05). During pregnancy, late gestation (OR=1.016, 95%CI: 1.006-1.025) and multiple induced/drug abortions (OR=1.329, 95%CI: 1.043-1.692) are risk factors for poor sleep quality (PSQI>5), while multiple full-term deliveries (OR=0.800, 95%CI: 0.675-0.949) is its protective factor. Advanced maternal age (OR=0.976, 95%CI: 0.956-0.997), multiple full-term deliveries (OR=0.808, 95%CI: 0.680-0.959), late gestation (OR=0.983, 95%CI: 0.974-0.992) and hypertension (OR=0.572, 95%CI: 0.401-0.814) are protective factors for daytime sleepiness (ESS>6). The high-risk pregnancy category (OR=9.312, 95%CI: 1.156-74.978) is a risk factor for insomnia (AIS≥4), while multiple full-term deliveries (OR=0.815, 95%CI: 0.691-0.961) is its protective factor. High BMI (OR=1.334, 95%CI: 1.270-1.402) and hypertension (OR=4.427, 95%CI: 2.539-7.719) are risk factors for high-risk SDB in pregnant women. Conclusions: The prevalences of various sleep disturbances are high throughout pregnancy. Noticeably, symptoms of maternal SDB develop along with pregnancy. Different types of sleep disturbances are associated with different factors. Women of high-risk pregnancy category, in late gestation, with high BMI, hypertension, a history of induced/drug abortion, or without a history of full-term delivery can be at high risk of sleep disturbances during pregnancy.
Child ; China/epidemiology* ; Cross-Sectional Studies ; Female ; Humans ; Pregnancy ; Pregnancy Complications/epidemiology* ; Pregnant Women ; Sleep ; Sleep Quality

Animals ; Lung/metabolism* ; Rats ; Silicon Dioxide/toxicity* ; Thioredoxins/metabolism*

[Abstract] Objective To investigate the effects of the downregulation of draxin expression on the projection characteristics of 23C10-positive neural fibers in the chick embryonic hindbrain. Methods The vitro incubation of HH stages 21-22 chick embryonic hindbrain biopsy with alkaline phosphatase (ALP) protein was used as control group. The incubation of HH stages 21-22 chick embryonic hindbrain biopsy with draxin-ALP fusion protein was used as experimental group. The number of embryonic hindbrain for each group was 10. To detect whether 23C10-positive neural fibers could directly bind to draxin protein or not;In ovo electroporation using empty vector in the chick embryonic hindbrain was used as control group. In ovo electroporation with small interfering RNA(siRNA) expressing vector for reducing draxin expression in the chick embryonic hindbrain was used as experimental group. The number of embryonic hindbrain for each group was 18. The effect of the down-regulation of draxin expression and the change of projection characteristics of 23C10-positive neural fibers were observed to check whether the down-regulation of draxin expression would affect the distribution of 23C10-positive fibers. Results Most portion of draxin protein could overlap with 23C10-positive neural fibers in HH stages 21-22 chick embryonic hindbrain biopsies; After expression of the siRNA plasmid against draxin by electroporation, the expression level of draxin protein was significantly reduced, and the distribution of 23C10-positive fibers was scattered in the dorsal hindbrain on the electroporated side at HH stages 25-26 of chick embryos (P < 0. 05) . Conclusion Draxin protein may directly bind to 23C10-positive fibers in hindbrain, and it plays an important regulatory role in the fasciculation of 23C10-positive fibers during chick embryonic development.

Additional sex combs-like 1 (ASXL1) interacts with BRCA1-associated protein 1 (BAP1) deubiquitinase to oppose the polycomb repressive complex 1 (PRC1)-mediated histone H2A ubiquitylation. Germline BAP1 mutations are found in a spectrum of human malignancies, while ASXL1 mutations recurrently occur in myeloid neoplasm and are associated with poor prognosis. Nearly all ASXL1 mutations are heterozygous frameshift or nonsense mutations in the middle or to a less extent the C-terminal region, resulting in the production of C-terminally truncated mutant ASXL1 proteins. How ASXL1 regulates specific target genes and how the C-terminal truncation of ASXL1 promotes leukemogenesis are unclear. Here, we report that ASXL1 interacts with forkhead transcription factors FOXK1 and FOXK2 to regulate a subset of FOXK1/K2 target genes. We show that the C-terminally truncated mutant ASXL1 proteins are expressed at much higher levels than the wild-type protein in ASXL1 heterozygous leukemia cells, and lose the ability to interact with FOXK1/K2. Specific deletion of the mutant allele eliminates the expression of C-terminally truncated ASXL1 and increases the association of wild-type ASXL1 with BAP1, thereby restoring the expression of BAP1-ASXL1-FOXK1/K2 target genes, particularly those involved in glucose metabolism, oxygen sensing, and JAK-STAT3 signaling pathways. In addition to FOXK1/K2, we also identify other DNA-binding transcription regulators including transcription factors (TFs) which interact with wild-type ASXL1, but not C-terminally truncated mutant. Our results suggest that ASXL1 mutations result in neomorphic alleles that contribute to leukemogenesis at least in part through dominantly inhibiting the wild-type ASXL1 from interacting with BAP1 and thereby impairing the function of ASXL1-BAP1-TF in regulating target genes and leukemia cell growth.