Optical microscopy is essential for exploring biological and material structures, with resolution determining the level of observable detail. The advent of super-resolution fluorescence microscopy has broken the diffraction limit, achieving nanoscale resolution. However, traditional assessment methods, such as the Rayleigh criterion and point spread function (PSF) width measurement, rely on empirical judgments and diffraction-limited models, rendering them inadequate for modern super-resolution imaging. This review systematically traces the evolution of resolution assessment methodologies, from classical criteria to advanced strategies tailored for various super-resolution modalities. We first discuss Fourier-based quantitative methods. Fourier ring correlation (FRC) and its 3D counterpart, Fourier shell correlation (FSC), objectively determine resolution by evaluating the statistical correlation of two independent image reconstructions in frequency space. These methods offer robustness against noise and provide a global resolution metric, but they require data independence and are computationally intensive. They have become the prevailing standards in electron and super-resolution microscopy. Subsequently, we examine adaptations for specific super-resolution techniques. For single-molecule localization microscopy (SMLM) techniques such as PALM and STORM, the Fourier image resolution (FIRE) method extends FRC by incorporating a physical model that accounts for localization precision and labeling density. For stimulated emission depletion (STED) microscopy and other nonlinear techniques, assessment strategies differ. While PSF shrinkage measurements using fluorescent beads are useful for system calibration, evaluating the effective resolution directly on biological samples is more practical. This is typically performed via linewidth analysis of known structures (e.g., microtubules) or edge-spread function measurements, capturing the effects of photobleaching and sample-induced aberrations. A major paradigm shift is parameter-free resolution estimation based on decorrelation analysis. This method analyzes the autocorrelation decay of a single image’s Fourier spectrum to identify the cutoff spatial frequency without requiring dual datasets or user-defined thresholds. Its high efficiency and broad applicability have been validated across widefield, confocal, STED, SIM, and SMLM modalities. Optimized rendering strategies for SMLM data further enhance its accuracy, and it is emerging as a tool for real-time optimization of experimental parameters. The review also addresses the “gold standard” of resolution validation using well-defined nanostructures, such as DNA origami and nuclear pore complexes, which provide ground truth for verifying resolution claims and detecting artifacts. In the era of artificial intelligence, deep learning plays a dual role: it powerfully enhances image resolution but also introduces challenges, as models may generate “hallucinations” or false details. This underscores the need for new validation metrics to verify the physical fidelity of AI-generated content. Finally, we outline future directions: developing unified cross-modality standards, enabling real-time dynamic resolution monitoring for live-cell imaging, creating techniques for generating local resolution maps to capture sample heterogeneity, and integrating intelligent error correction to ensure data veracity. By providing a comprehensive overview of resolution assessment progress and challenges, this review aims to equip researchers with the knowledge to select appropriate tools, thereby fostering rigorous quantitative imaging in the life and material sciences.

The ventral anterior (VA) nucleus of the thalamus is a major target of the basal ganglia and is closely associated with the pathogenesis of Parkinson's disease (PD). Notably, the VA receives direct innervation from the hypothalamic histaminergic system. However, its role in PD remains unknown. Here, we assessed the contribution of histamine to VA neuronal activity and PD motor deficits. Functional magnetic resonance imaging showed reduced VA activity in PD patients. Optogenetic activation of VA neurons or histaminergic afferents significantly alleviated motor deficits in 6-OHDA-induced PD rats. Furthermore, histamine excited VA neurons via H1 and H2 receptors and their coupled hyperpolarization-activated cyclic nucleotide-gated channels, inward-rectifier K⁺ channels, or Ca²⁺-activated K⁺ channels. These results demonstrate that histaminergic afferents actively compensate for Parkinsonian motor deficits by biasing VA activity. These findings suggest that targeting VA histamine receptors and downstream ion channels may be a potential therapeutic strategy for PD motor dysfunction.
Animals ; Histamine/metabolism* ; Male ; Oxidopamine/toxicity* ; Rats ; Ventral Thalamic Nuclei/physiopathology* ; Rats, Sprague-Dawley ; Disease Models, Animal ; Parkinson Disease/metabolism* ; Neurons/physiology* ; Humans ; Optogenetics

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.

Hypoxia-inducible factor (HIF-1α), a core transcription factor responding to changes in cellular oxygen levels, is closely associated with a wide range of physiological and pathological conditions. However, its differential impacts on vascular cell types and molecular programs modulating human vascular homeostasis and regeneration remain largely elusive. Here, we applied CRISPR/Cas9-mediated gene editing of human embryonic stem cells and directed differentiation to generate HIF-1α-deficient human vascular cells including vascular endothelial cells, vascular smooth muscle cells, and mesenchymal stem cells (MSCs), as a platform for discovering cell type-specific hypoxia-induced response mechanisms. Through comparative molecular profiling across cell types under normoxic and hypoxic conditions, we provide insight into the indispensable role of HIF-1α in the promotion of ischemic vascular regeneration. We found human MSCs to be the vascular cell type most susceptible to HIF-1α deficiency, and that transcriptional inactivation of ANKZF1, an effector of HIF-1α, impaired pro-angiogenic processes. Altogether, our findings deepen the understanding of HIF-1α in human angiogenesis and support further explorations of novel therapeutic strategies of vascular regeneration against ischemic damage.
Humans ; Vascular Endothelial Growth Factor A/metabolism* ; Endothelial Cells/metabolism* ; Transcription Factors/metabolism* ; Gene Expression Regulation ; Hypoxia/metabolism* ; Cell Hypoxia/physiology*

Objective To observe the effect of omeprazole enteric-coated capsules on clinical symptoms and serum inflammatory factor levels in children with chronic gastritis and peptic ulcer.Methods Children with chronic gastritis and peptic ulcer were divided into treatment group and control group by random number table method.The control group was given triple therapy of ranitidine hydrochloride tablets,amoxicillin and clarithromycin,while the treatment group was treated with omeprazole enteric-coated capsules combined with amoxicillin and clarithromycin.Clinical efficacy,symptom relief time,and changes in serum motilin(MOT),gastrin(GAS)and inflammatory factors[interlrukin-6(IL-6)and interlrukin-8(IL-8)]were compared between the two groups.Results There were 48 cases in treatment group and 48 cases in control group.After treatment,the total effective rates in treatment group and control group were 93.74％(45 cases/48 cases)and 85.42％(41 cases/48 cases),with significant difference(P＜0.05).After treatment,the disappearance time of ulcer induced pain in treatment group and control group were(1.51±0.26)and(2.08±0.42)d;the disappearance time of acid regurgitation were(2.29±0.40)and(2.93±0.33)d;the disappearance time of burning sensation were(2.37±0.21)and(2.85±0.54)d;the length of hospital stay were(6.21±1.07)and(6.94±1.25)d;serum MOT levels were(298.48±35.15)and(273.58±31.25)pg·mL-1;serum GAS levels were(167.28±19.46)and(128.32±18.61)ng·L-1;IL-6 levels were(58.67±5.39)and(76.14±6.63)mg·mL-1;IL-8 levels were(50.08±5.16)and(58.68±5.49)mg·mL-1.The above indexes were significantly different between control group and treatment group(all P＜0.05).The total incidence of adverse drug reactions in treatment group and control group were 8.33％and 12.50％,with no statistical significance(P＞0.05).Conclusion Omeprazole enteric-coated capsules in the treatment of children with chronic gastritis and peptic ulcer can effectively alleviate various clinical symptoms and improve clinical efficacy.At the same time,it can lower serum levels of inflammatory factors and improve inflammation,with good effect.

Objective To investigate whether curcumin is a potential drug for the treatment of gastrointestinal stromal tumors(GIST).Methods The differential genes of imatinib-resistant cells and non-resistant cells were analyzed by cell transcriptology.The antitumor activity of curcumin was verified by cell counting kit-8(CCK-8)method,and the concentration of Curcumin ranged from 5 to 80 μg·mL-1for GIST-T1 and GIST-T1/IMR cells.20 μg·mL-1 Curcumin as the experimental group,phosphate buffered solution as the control group.The contents of interleukin-6(IL-6),reactive oxygen species(ROS)and nitric oxide(NO)were measured by enzyme linked immunosorbent assay.The cell cycle changes were analyzed by flow cytometry.Results Using non-resistant cells as a contrast,the results showed that there were 1 300 up-regulated genes and 1 609 down-regulated genes in imatinib-resistant cells.The 50％inhibiting concentration values of Curcumin on GIST-T1 and GIST-T1/IMR cells were(15.33±1.36)and(10.49±2.12)μg·mL-1,respectively.In GIST-T1 cells,the IL-6 levels in experimental group and control group were(3.45±0.01)and(5.64±0.42)pg·mL-1;the ROS levels were(2 841.42±81.83)and(4 174.32±439.12)pg·mL-1;the iNOS levels were(7.02±0.08)and(8.08±0.03)μmol·L-1,respectively.In GIST-T1/IMR cells,the IL-6 levels in experimental group and control group were(2.47±0.30)and(6.30±0.01)pg·mL-1;the ROS levels were(4 706.40±146.71)and(8 254.34±342.35)pg·mL-1;the iNOS levels were(6.42±0.09)and(7.29±0.04)μmol·L-1,respectively.Among the 2 cells,the differences of above indicators were statistically significant between the experimental group and the control group(P＜0.05,P＜0.01).Curcumin blocked the cell cycle of GIST-T1 and GIST-T1/IMR in G1 phase,further shortens S phase and G2 phase.Conclusion Curcumin can inhibit the secretion of inflammation and regulate the proliferation of GIST.

AIM To prepare curcumin-loaded poly (D,L-lactide-co-glycolide) acid (PLGA) nanoparticles,and to investigate their effects on promoting wound healing.METHODS Phacoemulsification method was adopted in the preparation of PLGA nanoparticles.With lactic acid-glycolic acid ratio,surfactant type and concentration and PLGA consumption as influencing factors,encapsulation efficiency,drug loading,particle size and PDI as evaluation indices,the preparation process was optimized by single factor test.The morphology was observed under transmission electron microscopy,after which the in vitro drug release was determined by dialysis bag method,the optical properties were investigated by fluorescence spectroscopy,and the effects on promoting wound healing of mouse skin.RESULTS The optimal conditions were determined to be 50∶50 for lactic acid-glycolic acid ratio,60 mg for PLGA consumption,and 3％ for surfactant (PVA) concentration.The obtained PLGA nanoparticles with spherical core-shell structure demonstrated the average particle size,PDI,Zeta potential and accumulative release rate within 168 h of (149.70±7.27) nm,0.28±0.04 and (-10.18±1.00) mV and (39.21±1.44)％,respectively,which displayed typical aggregation-induced emission property,excitation wavelength-dependent property and optical stability.Compared with the PBS group,PBS+illumination group,curcumin+illumination group and preparation group,the preparation+illumination group exhibited increased wound healing rate (P<0.05,P<0.01) and reduced wound epidermal thickness (P<0.05,P<0.01).CONCLUSION Curcumin-loaded PLGA nanoparticles show good optical properties,which can promote the wound healing of mouse skin when combined with photodynamic therapy.

AIM To prepare curcumin-loaded poly (D,L-lactide-co-glycolide) acid (PLGA) nanoparticles,and to investigate their effects on promoting wound healing.METHODS Phacoemulsification method was adopted in the preparation of PLGA nanoparticles.With lactic acid-glycolic acid ratio,surfactant type and concentration and PLGA consumption as influencing factors,encapsulation efficiency,drug loading,particle size and PDI as evaluation indices,the preparation process was optimized by single factor test.The morphology was observed under transmission electron microscopy,after which the in vitro drug release was determined by dialysis bag method,the optical properties were investigated by fluorescence spectroscopy,and the effects on promoting wound healing of mouse skin.RESULTS The optimal conditions were determined to be 50∶50 for lactic acid-glycolic acid ratio,60 mg for PLGA consumption,and 3％ for surfactant (PVA) concentration.The obtained PLGA nanoparticles with spherical core-shell structure demonstrated the average particle size,PDI,Zeta potential and accumulative release rate within 168 h of (149.70±7.27) nm,0.28±0.04 and (-10.18±1.00) mV and (39.21±1.44)％,respectively,which displayed typical aggregation-induced emission property,excitation wavelength-dependent property and optical stability.Compared with the PBS group,PBS+illumination group,curcumin+illumination group and preparation group,the preparation+illumination group exhibited increased wound healing rate (P<0.05,P<0.01) and reduced wound epidermal thickness (P<0.05,P<0.01).CONCLUSION Curcumin-loaded PLGA nanoparticles show good optical properties,which can promote the wound healing of mouse skin when combined with photodynamic therapy.

AIM: To investigate the influence of the duration of orthokeratology lens cessation on patients' refractive status and corneal endothelial cells.METHODS: Adolescent myopia patients who wore orthokeratology lens from July 2019 to July 2020 and recently planned to stop wearing the lens were divided into mild group and severe group according to spherical equivalent. Refractive status, corneal morphology, corneal endothelial cells, and visual quality were measured at cessation and 1, 2 and 3mo after cessation.RESULTS: The corneal flat K values, steep K values and mean K values in the two groups were lower at cessation than those before wearing lenses. These values returned to the level before wearing lenses at 2mo after cessation(P>0.05). The corneal astigmatism, surface regularity index and surface asymmetry index in each group showed no statistically significant difference before wearing lenses and at 1, 2 and 3mo after cessation(P>0.05). There was no significant change in corneal endothelial cell density of the two groups at 1, 2 and 3mo after cessation compared with those before wearing lenses(P>0.05). The proportion of hexagonal cells in the two groups was lower at cessation than that before wearing lenses, and it returned to the level before wearing lenses at 1mo after cessation(P>0.05).CONCLUSION: Corneal morphology and corneal endothelial cells can be restored to the level before wearing orthokeratology lens at 3mo after cessation.

The twenty-first century has already recorded more than ten major epidemics or pandemics of viral disease, including the devastating COVID-19. Novel effective antivirals with broad-spectrum coverage are urgently needed. Herein, we reported a novel broad-spectrum antiviral compound PAC5. Oral administration of PAC5 eliminated HBV cccDNA and reduced the large antigen load in distinct mouse models of HBV infection. Strikingly, oral administration of PAC5 in a hamster model of SARS-CoV-2 omicron (BA.1) infection significantly decreases viral loads and attenuates lung inflammation. Mechanistically, PAC5 binds to a pocket near Asp49 in the RNA recognition motif of hnRNPA2B1. PAC5-bound hnRNPA2B1 is extensively activated and translocated to the cytoplasm where it initiates the TBK1-IRF3 pathway, leading to the production of type I IFNs with antiviral activity. Our results indicate that PAC5 is a novel small-molecule agonist of hnRNPA2B1, which may have a role in dealing with emerging infectious diseases now and in the future.
Animals ; Mice ; Antiviral Agents/pharmacology* ; COVID-19 ; Hepatitis B virus ; Interferon Type I/metabolism* ; SARS-CoV-2/drug effects* ; Heterogeneous-Nuclear Ribonucleoprotein Group A-B/antagonists & inhibitors*