Structural mechanism of human HCN1 hyperpolarization-activated channel inhibition by ivabradine.

The hyperpolarization-activated cyclic nucleotide-gated (HCN) channels play a crucial role in regulating neuronal excitability. Despite growing evidence supporting the therapeutic potential of HCN1 inhibition in treating neurological disorders, the structural basis of channel inhibition by inhibitor has remained elusive. Here, we present the cryo-electron microscopy structure of human HCN1 channel in complex with inhibitor ivabradine, the drug on the market that acts on HCN channels. Combining electrophysiology, mutagenesis, and molecular dynamics simulations, our findings reveal that ivabradine binds to a previously unidentified pocket formed between the S4, S1, and HCN domain. Furthermore, through structure-based virtual screening, we identify two FDA-approved drugs that can inhibit the HCN1 channel by interacting with the ivabradine-binding site. Our results not only provide insights into the structural intricacies of ivabradine-mediated inhibition, but also offer a potential pharmacological framework for developing novel drugs targeting the HCN1 channel. The elucidation of these molecular interactions serves as a foundational step in advancing therapeutic strategies for modulating HCN1 activity, contributing to the broader landscape of drug discovery and development in this area.

Cryo-EM structure of human HCN3 channel and its regulation by cAMP.

HCN channels are important for regulating heart rhythm and nerve activity and have been studied as potential drug targets for treating depression, arrhythmia, nerve pain, and epilepsy. Despite possessing unique pharmacological properties, HCN channels share common characteristics in that they are activated by hyperpolarization and modulated by cAMP and other membrane lipids. However, the mechanisms of how these ligands bind and modulate HCN channels are unclear. In this study, we solved structures of full-length human HCN3 using cryo-EM and captured two different states, including a state without any ligand bound and a state with cAMP bound. Our structures reveal the novel binding sites for cholesteryl hemisuccinate in apo state and show how cholesteryl hemisuccinate and cAMP binding cause conformational changes in different states. These findings explain how these small modulators are sensed in mammals at the molecular level. The results of our study could help to design more potent and specific compounds to influence HCN channel activity and offer new therapeutic possibilities for diseases that lack effective treatment.

Downregulation of HNRNPA1 induced neoantigen generation via regulating alternative splicing.

BACKGROUND: Immunotherapies effectively treat human malignancies, but the low response and resistance are major obstacles. Neoantigen is an emerging target for tumor immunotherapy that can enhance anti-tumor immunity and improve immunotherapy. Aberrant alternative splicing is an important source of neoantigens. HNRNPA1, an RNA splicing factor, was found to be upregulated in the majority of tumors and play an important role in the tumor immunosuppressive microenvironment. METHODS: Whole transcriptome sequencing was performed on shHNRNPA1 SKOV3 cells and transcriptomic data of shHNRNPA1 HepG2, MCF-7M, K562, and B-LL cells were downloaded from the GEO database. Enrichment analysis was performed to elucidate the mechanisms underlying the activation of anti-tumor immunity induced by HNRNPA1 knockdown. mRNA alternative splicing was analyzed and neoantigens were predicted by JCAST v.0.3.5 and Immune epitope database. The immunogenicity of candidate neoantigens was calculated by Class I pMHC Immunogenicity and validated by the IFN-γ ELISpot assay. The effect of shHNRNPA1 on tumor growth and immune cells in vivo was evaluated by xenograft model combined with immunohistochemistry. RESULTS: HNRNPA1 was upregulated in a majority of malignancies and correlated with immunosuppressive status of the tumor immune microenvironment. Downregulation of HNRNPA1 could induce the activation of immune-related pathways and biological processes. Disruption of HNRNPA1 resulted in aberrant alternative splicing events and generation of immunogenic neoantigens. Downregulation of HNRNPA1 inhibited tumor growth and increased CD8+ T cell infiltration in vivo. CONCLUSION: Our study demonstrated that targeting HNRNPA1 could produce immunogenic neoantigens that elicit anti-tumor immunity by inducing abnormal mRNA splicing. It suggests that HNRNPA1 may be a potential target for immunotherapy.

Ultrafast evanescently coupled waveguide MUTC-PDs with high responsivity.

Novel evanescently coupled waveguide modified uni-traveling carrier photodiodes (MUTC-PDs) employing a thick multi-layer coupling waveguide are reported. To improve the optical-to-electrical (O/E) conversion efficiency, a thick multi-layer coupling waveguide with a gradually increased refractive index from the bottom layer to the absorption layer is utilized. The refractive index profile facilitates the upward transmission of incident light into the absorption region, thereby enhancing the evanescent coupling efficiency. Meanwhile, the coupling waveguide, with a total thickness of 1.75 µm, expands the mode field diameter, thereby reducing the input coupling loss. Additionally, the top layer of the coupling waveguide also serves as the drift layer. This configuration facilitates efficient light absorption within a short PD length, thus ensuring ultrawide bandwidth and high O/E conversion efficiency simultaneously. Without an additional spot size coupler or anti-reflection coating, the measured responsivity is as high as 0.38 A/W for the PD with an active area of 5 × 6 µm2. Meanwhile, an ultrawide 3-dB bandwidth of 153 GHz has been demonstrated.

Interventions for Postextubation Dysphagia in Critically Ill Patients: A Systematic Review and Meta-analysis.

OBJECTIVE: This review evaluates the efficacy and safety of dysphagia interventions for patients with prolonged endotracheal intubation (⩾48 h) in critical care units. DATA SOURCES: We systematically searched PubMed, Cochrane Library, Medline, Embase, OVID, CINAHL, Wanfang (China), CNKI (China), and ProQuest Dissertations for studies published up to December 31, 2023. STUDY SELECTION: Inclusion criteria encompassed randomized controlled trials (RCTs), quasi-randomized trials, and cohort studies comparing dysphagia rehabilitation - such as swallowing stimulation, swallowing and respiratory muscle exercise, and neuromuscular electrical stimulation - with standard care or no treatment. The primary outcomes assessed were dysphagia severity, time to resume oral intake, and incidence of aspiration and aspiration pneumonia. DATA EXTRACTION: Detailed information on study design, setting, participant demographics, interventions, and outcomes was systematically extracted. DATA SYNTHESIS: Our analysis included ten studies with a total of 1031 participants. The findings demonstrate a significant reduction in dysphagia severity, time to oral intake and the risk of aspiration pneumonia, and an improvement in quality of life among patients receiving swallowing therapy. However, no substantial difference was found in nutritional status. Limited data availability necessitated a descriptive presentation of outcomes like the risk of aspiration, ICU/hospital stay duration, pharyngeal/oral residue severity, and intervention-related adverse events. CONCLUSION: The current evidence for the effectiveness of dysphagia interventions in critically ill patients with prolonged endotracheal intubation is limited. There is a pressing need for future research, particularly high-quality RCTs employing standardized outcome measures, to substantiate these findings.

Dysphagia Pattern in Early to Moderate Parkinson's Disease Caused by Abnormal Pharyngeal Kinematic Function.

Airway invasion is common in patients with Parkinson's disease (PD) and can cause serious complications. However, a PD-related dysphagic pattern has not been clearly elucidated. In this study, 53 patients with early to moderate PD were enrolled to undergo a videofluoroscopic study of swallowing evaluation (VFSS) and a battery of neuropsychological assessments. A set of VFSS variables (three visuoperceptual, nine temporal, and six spatial) were measured. The main effects of bolus viscosity and volume on airway invasion were calculated. Statistical analyses were performed to determine key kinematic factors of airway invasion for swallowing each bolus type. Airway invasion frequency was significantly higher for liquid boluses (liquid vs. pudding P < 0.001; liquid vs. honey P = 0.006). Laryngeal vestibule closure reaction time (LVCrt) was the key kinematic factor of airway invasion for 3 ml liquid swallow (P = 0.040), anterior displacement of hyoid bone was the key kinematic factor for both 5 ml and 10 ml liquid swallows (P = 0.010, 0.034, respectively). Male sex and advanced Hoehn and Yahr stage were significantly related to reduced anterior displacement of hyoid bone. These results reveal the dysphagic pattern related to PD, demonstrating that prolonged LVCrt and reduced anterior displacement of hyoid bone are two crucial kinematic factors contributing to airway invasion during the liquid swallow. In addition, hyoid bone dysfunction was correlated with disease severity and male sex. Our findings warrant further investigation of the pathophysiological mechanism of dysphagia in PD and would guide clinical intervention.

Long-Life All-Solid-State Batteries Enabled by Cold-Pressed Garnet Composite Electrolytes with Enhanced Li+ Conduction.

Garnet Li7La3Zr2O12 (LLZO)-based solid-state electrolytes (SSEs) hold promise for realizing next-generation lithium metal batteries with high energy density. However, the high stiffness of high-temperature sintered LLZO makes it brittle and susceptible to strain during the fabrication of solid-state batteries. Cold-pressed LLZO exhibits improved ductility but suffers from insufficient Li+ conductivity. Here, we report cold-pressed Ta-doped LLZO (Ta-LZ) particles integrated with ductile Li6PS5Cl (LPSC) via a Li+ conductive Li-containing Ta-Cl structure. This configuration creates a continuous Li+ conduction network by enhancing the Li+ exchange at the Ta-LZ/LPSC interface. The resulting Ta-LZ/LPSC SSE exhibits Li+ conductivity of 4.42 × 10-4 S cm-1 and a low activation energy of 0.31 eV. Li symmetric cells with Ta-LZ/LPSC SSE demonstrate excellent Li dendrite suppression ability, with an improved critical current density of 5.0 mA cm-2 and a prolonged cycle life exceeding 600 h at 1 mA cm-2. Our finding provides valuable insights into developing cold-pressed ceramic powder electrolytes for high-performance all-solid-state batteries.

Fibroblast growth factor 5 protects against spinal cord injury through activating AMPK pathway.

Excessive productions of inflammatory cytokines and free radicals are involved in spinal cord injury (SCI). Fibroblast growth factor 5 (FGF5) is associated with inflammatory response and oxidative damage, and we herein intend to determine its function in SCI. Lentivirus was instilled to overexpress or knockdown FGF5 expression in mice. Compound C or H89 2HCl were used to suppress AMP-activated protein kinase (AMPK) or protein kinase A (PKA), respectively. FGF5 level was significantly decreased during SCI. FGF5 overexpression mitigated, while FGF5 silence further facilitated inflammatory response, oxidative damage and SCI. Mechanically, FGF5 activated AMPK to attenuate SCI in a cAMP/PKA-dependent manner, while inhibiting AMPK or PKA with pharmacological methods significantly abolished the neuroprotective effects of FGF5 against SCI. More importantly, serum FGF5 level was decreased in SCI patients, and elevated serum FGF5 level often indicate better prognosis. Our study identifies FGF5 as an effective therapeutic and prognostic target for SCI.

Localized Alkaline Environment via In Situ Electrostatic Confinement for Enhanced CO2-to-Ethylene Conversion in Neutral Medium.

Electrocatalytic CO2 reduction reaction (CO2RR) is one of the most promising routes to facilitate carbon neutrality. An alkaline electrolyte is typically needed to promote the production of valuable multi-carbon molecules (such as ethylene). However, the reaction between CO2 and OH- consumes a significant quantity of CO2/alkali and causes the rapid decay of CO2RR selectivity and stability. Here, we design a catalyst-electrolyte interface with an effective electrostatic confinement of in situ generated OH- to improve ethylene electrosynthesis from CO2 in neutral medium. In situ Raman measurements indicate the direct correlation between ethylene selectivity and the intensities of surface Cu-CO and Cu-OH species, suggesting the promoted C-C coupling with the surface enrichment of OH-. Thus, we report a CO2-to-ethylene Faradaic efficiency (FE) of 70% and a partial current density of 350 mA cm-2 at -0.89 V vs the reversible hydrogen electrode. Furthermore, the system demonstrated a 50 h stable operation at 300 mA cm-2 with an average ethylene FE of ∼68%. This study offers a universal strategy to tune the reaction micro-environment, and a significantly improved ethylene FE of 64.5% was obtained even in acidic electrolytes (pH = 2).

Ultrafast MUTC photodiodes over 200†GHz with high saturation power.

Novel back-illuminated modified uni-traveling-carrier photodiodes (MUTC-PDs) with wide bandwidth and high saturation power are demonstrated. The effect of cliff layer doping on the electric field distribution is investigated to achieve fast carrier transport. MUTC-PDs with miniaturized device diameter and low contact resistance are fabricated to improve the RC-limited bandwidth. Meanwhile, inductive peaking is implemented to further extend the bandwidth. PDs with 3-µm and 3.6-µm-diameter exhibit a ultrawide bandwidth of 230 GHz and 200 GHz, together with -4.94 dBm and -2.14 dBm saturation power at 220 GHz and 200 GHz, respectively.

Extended ray-mapping method based on differentiable ray-tracing for non-paraxial and off-axis freeform illumination lens design.

The ray-mapping method has been widely used for designing freeform illumination lenses. However, in non-paraxial or off-axis situations, it remains challenging to obtain an integrable ray-mapping, often requiring a complex iterative correction process for the initial mapping. To address this challenge, we propose an extended ray-mapping method that incorporates differentiable ray-tracing into the design pipeline of the ray-mapping method. This enables accurate surface construction according to ray-mapping and efficient shape correction based on irradiance distribution. The proposed method involves two optimization stages. In the first stage, the freeform surface is preliminarily optimized to closely match the optimal transport mapping. The obtained freeform surface is then further optimized in the second stage to minimize the divergence between the target and simulated irradiance distributions. Additionally, the mean curvature of the freeform surface is also constrained in the second stage to facilitate the fabrication of the final freeform surface. Non-paraxial illumination lenses and off-axis illumination lenses have been designed using the proposed method within ten minutes, and simulations demonstrate that the approach is effective and robust.

Simple and accurate dispersion measurement of GaN microresonators with a fiber ring.

The dispersion characteristics of a microresonator are important for applications in nonlinear optics, and precise measurement of the dispersion profile is crucial to device design and optimization. Here we demonstrate the dispersion measurement of high-quality-factor gallium nitride (GaN) microrings by a single-mode fiber ring, which is simple and convenient to access. Once the dispersion parameters of the fiber ring have been determined by the opto-electric modulation method, the dispersion can be obtained from the microresonator dispersion profile by polynomial fitting. To further verify the accuracy of the proposed method, the dispersion of the GaN microrings is also evaluated with frequency comb-based spectroscopy. Dispersion profiles obtained with both methods are in good agreement with simulations based on the finite element method.

Design and synthesis of 1H-pyrazolo[3,4-d]pyrimidine derivatives as hematopoietic progenitor kinase 1 (HPK1) inhibitors.

Despite immune checkpoint inhibitors' tremendous success in the treatment of tumors, the moderate response rate limits their widespread use. Hematopoietic progenitor kinase 1 (HPK1) is served as an essential negative regulator of T-cell receptor, which has been identified as a promising target for enhancing antitumor immunity. However, the development of a selective HPK1 inhibitor is still challenging. Herein, we reported a novel series of 1H-pyrazolo[3,4-d]pyrimidine derivatives as HPK1 inhibitors by structure-based rational design. The optimal compound 10n significantly inhibited HPK1 with an IC50 value of 29.0 nM and the phosphorylation of SLP76 at a concentration as low as 0.1 µM. Furthermore, compound 10n exhibited good selectivity over a panel of 25 kinases, including GLK from the same MAP4K family. Together, the current study provided a novel, potent, and selective HPK1 inhibitor, acting as a lead compound for the future development of cancer immunotherapy.

Structure-activity relationship study of a series of nucleoside derivatives bearing sulfonamide scaffold as potent and selective PRMT5 inhibitors.

Protein arginine methyltransferase 5 (PRMT5) is a promising target for the treatment of malignant tumors. The discovery of nucleoside-derived inhibitors against PRMT5 with novel scaffold has been challenging. Herein, we report our effort on the design and synthesis of nucleoside derivatives bearing sulfonamide scaffold as potent PRMT5 inhibitors. The representative compound 23n was identified as a potent and selective PRMT5 inhibitor with an IC50 value of 8 nM. Molecular docking study demonstrated the binding mode of compound 23n and illustrated its inhibitory activity to PRMT5. The Trimethyl Lock prodrug strategy was used to afford prodrug 36 with lower polarity which could rapidly release the active compound 23n after entering the tumor cells. Cell-based assays revealed that the prodrug 36 restrained the proliferation of Z-138 and MOLM-13 cells and suppressed methylation of PRMT5 substrate more potently than 23n. Additionally, both compound 23n and 36 exerted antiproliferative effects against Z-138 cells mainly by inducing apoptosis effectively rather than arresting cell cycle. Thus, compounds 23n and 36 represent a series of potent PRMT5 inhibitor with novel scaffold.

Engineering a conformal optical window of a square-to-circular transition isolator.

To realize the flow visualization of shock train structures by Schlieren measurements in a square-to-circular transition isolator, a high-precision conformal optical window was manufactured by fly-cutting technology. According to the light refraction principle, the window's outer surface was iteratively optimized based on the super-elliptic curves of the internal flow channel. Through tolerance analysis and processing parameter optimization, the transmitted wavefront error (RMS value) of the finished window was 0.823λ (λ=632.8n m). Based on a z-type Schlieren apparatus, the high-precision Schlieren measurements were conducted through the window and processed by an image filtering process method. The results promote high-precision Schlieren observation towards square-to-circular transition isolators.

Design, synthesis and biological evaluation of 4-aminoquinoline derivatives as receptor-interacting protein kinase 2 (RIPK2) inhibitors.

Receptor-interacting protein kinase 2 (RIPK2) is an essential protein kinase mediating signal transduction by NOD1 and NOD2, which play an important role in regulating immune signalling. In this study, we designed and synthesised a novel series of 4-aminoquinoline-based derivatives as RIPK2 inhibitors. In vitro, compound 14 exhibited high affinity (IC50 = 5.1 ± 1.6 nM) and excellent selectivity to RIPK2 showing in a dendrogram view of the human kinome phylogenetic tree. Bearing favourable lipophilicity and eligible lipophilic ligand efficiency (LipE), compound 14 was selected to investigate cellular anti-inflammatory effect and was identified as a potent inhibitor to reduce the secretion of MDP-induced TNF-α with a dose-dependent manner. Moreover, compound 14 showed moderate stability in human liver microsome. Given these promising results, compound 14 could serve as a favourable inhibitor of RIPK2 for further physiological and biochemical research so as to be used in therapeutic treatment.

[Double-channel expansion of the subcutaneous lower abdominal tunnel for sequential inguinal lymph node dissection in penile cancer - Report of six cases].

OBJECTIVE: To investigate the safety and efficacy of the two-channel dilatation procedure for subcutaneous tunneling in the lower abdomen during pelvic lymph node dissection for penile cancer. METHODS: A retrospective analysis was conducted on the clinical data of 6 patients treated from January 2020 to December 2022 using the dual-channel expansion technique for penile cancer lymph node dissection. RESULTS: All 6 cases ( 12 sides) successfully underwent prophylactic inguinal lymph node dissection. The average laparoscopic dissection time was ( 82.50 ± 12.08) minutes per side, with an average blood loss of （28.33 ± 10.95） ml. The number of lymph nodes dissected was （11.16 ± 1.02） for the superficial group and ( 0.67 ± 0.74 ) for the deep group. Postoperative pathology was negative in all cases. The average postoperative hospital stay was （7.33 ± 1.60 ） days, with a catheter removal time of （12.00 ± 2.06）days. Postoperative complications included abnormal skin sensations in 5 sides, lower limb edema in 3 sides, lymphedema in 3 sides, and cellulitis in 1 side. During a follow-up period of （20.60 ± 12.51）months, there were no instances of tumor recurrence or metastasis in the inguinal region among the patients. CONCLUSION: The dual-channel expansion technique for inguinal lymph node dissection via a subcutaneous tunnel is a safe and feasible treatment for penile cancer. It has a low complication rate, allows for thorough dissection of inguinal lymph nodes, and offers advantages in terms of surgical time.

Regulating Frozen Electrolyte Structure with Colloidal Dispersion for Low Temperature Aqueous Batteries.

Electrolyte freezing under low temperatures is a critical challenge for the development of aqueous batteries (ABs). While lowering the freezing point of the electrolyte has caught major research efforts, limited attention has been paid to the structural evolution during the electrolyte freezing process and regulating the frozen electrolyte structure for low temperature ABs. Here, we reveal the formation process of interconnected liquid regions for ion transport in frozen electrolytes with various in situ variable-temperature technologies. More importantly, the low-temperature performance of ABs was significantly improved with the colloidal electrolyte design using graphene oxide quantum dots (GOQDs), which effectively inhibits the growth of ice crystals and expands the interconnected liquid regions for facial ion transport. This work provides new insights and a promising strategy for the electrolyte design of low-temperature ABs.

Membrane multiple quantum well electro-optical modulator employing low loss high-k radio-frequency slot waveguides.

A membrane multiple quantum well (MQW) electro-optical (EO) modulator exploiting low loss high-k radio-frequency (RF) slot waveguides is proposed for sub-terahertz bandwidth. By employing high-k barium titanate (BTO) claddings in place of doped InP cladding layers in traditional InP-based MQW modulators, the proposed modulator exhibits enhanced modulation efficiency and bandwidth as well as reduced insertion loss. A low half-wave voltage-length product of 0.24 V·cm is estimated, together with over 240 GHz bandwidth for a 2-mm-long modulation region, thus allowing sub-terahertz operation.

Dual-tracer PET/CT-targeted, mpMRI-targeted, systematic biopsy, and combined biopsy for the diagnosis of prostate cancer: a pilot study.

PURPOSE: Growing evidence proved the efficacy of multi-parametric MRI (mpMRI) and prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT)-guided targeted biopsy (TB) in prostate cancer (PCa) diagnosis, but there is no direct comparison between mpMRI-TB and PSMA PET/CT-TB. Gastrin-releasing peptide receptor (GRPR) is highly expressed in PCa, which can compensate for the unstable expression of PSMA in PCa. Therefore, we designed a study to compare the efficiency of mpMRI-TB, dual-tracer (GRPR and PSMA) PET/CT-TB, systematic biopsy, and combined biopsy for the diagnosis of prostate cancer. METHODS: One hundred twelve suspicious PCa patients were enrolled from September 2020 to June 2021. Patients with anyone of positive dual-tracer PET/CT or mpMRI underwent TB, and all enrolled patients underwent systematic biopsy (SB) after TB. The primary outcome was the detection rates of PCa in different biopsy strategies. Secondary outcomes were the performance of three imaging methods, omission diagnostic rates, and upgrading and downgrading of biopsy samples relative to those of prostatectomy specimens in different biopsy strategies. McNemar's tests and Bonferroni correction in multiple comparisons were used to compare the primary and secondary outcomes. RESULTS: In 112 men, clinically significant PCa (grade group[GG] ≥ 2) accounted for 34.82% (39/112), and nonclinically significant PCa (GG = 1) accounted for 4.46% (5/112). 68 Ga-PSMA PET/CT-TB achieved higher PCa detection rate (69.77%) and positive ratio of biopsy cores (0.44) compared with SB (39.29% and 0.12) and mpMRI-TB (36.14% and 0.23), respectively (P < 0.005). Dual-tracer PET/CT screen out patients for avoiding 52.67% (59/112) unnecessary biopsy, whereas dual-tracer PET/CT-TB plus SB achieved high detection rate (77.36%) without misdiagnosis of csPCa. CONCLUSION: Dual-tracer PET/CT might screen patients for avoiding unnecessary biopsy. Dual-tracer PET/CT-TB plus SB might be a more effective and promising strategy for the definite diagnosis of clinically significant PCa than mpMRI-TB.