Therapeutic effects of tetrahedral framework nucleic acids and tFNAs-miR22 on retinal ischemia/reperfusion injury.

Retinal ischemia/reperfusion injury (RI/R) is a common pathological process in ophthalmic diseases, which can cause severe visual impairment. The mechanisms underlying RI/R damage and repair are still unclear. Scholars are actively exploring effective intervention strategies to restore impaired visual function. With the development of nucleic acid nanomaterials, tetrahedral framework nucleic acids (tFNAs) have shown promising therapeutic potential in various fields such as stem cells, biosensors, and tumour treatment due to their excellent biological properties. Besides, miRNA-22-3p (miR-22), as an important regulatory factor in neural tissue, has been proven to have positive effects in various neurodegenerative diseases. By stably constructing a complex of tetrahedral framework nucleic acids miR22 (tFNAs-miR22), we observed that tFNAs-miR22 had a positive effect on the repair of RI/R injury in retinal neural tissue. Previous studies have shown that tFNAs can effectively deliver miR-22 into damaged retinal neurons, subsequently exerting neuroprotective effects. Interestingly, we found that there was a certain synergistic effect between tFNAs and miR-22. tFNAs-miR22 can selectively activated the ERK1/2 signalling pathway to reduce neuronal apoptosis, accelerate cell proliferation, and restore synaptic functional activity. In this study, we established a simple yet effective small molecule drug for RI/R treatment which may become a promising neuroprotectant for treating this type of vision impairment disease in the future.

DEAD/H-box helicase 11 is transcriptionally activated by Yin Yang-1 and accelerates oral squamous cell carcinoma progression.

Oral squamous cell carcinoma (OSCC) is the most common oral malignancy. DEAD/H-box helicase 11 (DDX11), a DNA helicase, has been implicated in the progression of several cancers. Yet, the precise function of DDX11 in OSCC is poorly understood. The DDX11 expression in OSCC cells and normal oral keratinocytes was evaluated in the Gene Expression Omnibus database (GSE146483 and GSE31853). SCC-4 and CAL-27 cells expressing doxycycline-inducible DDX11 or DDX11 shRNA were generated by lentiviral infection. The role of DDX11 in OSCC cells was determined by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, colony formation assay, flow cytometry assay, TUNEL staining, and western blot. The effects of DDX11 on tumor growth were explored in a xenograft nude mouse model. The relationship between DDX11 and transcription factor Yin Yang-1 (YY1) was researched using the dual luciferase report assay and chromatin immunoprecipitation assay. DDX11 expression was significantly upregulated in OSCC cells. Knockdown of DDX11 inhibited cell proliferation, induced cell cycle arrest, and suppressed PI3K-AKT pathway, while DDX11 overexpression showed opposite effects. The number of apoptotic cells was increased in DDX11 silenced cells. DDX11 upregulation or knockdown accelerated or suppressed tumor growth in vivo, respectively. Moreover, the YY1 bound and activated the DDX11 promoter, resulting in increasing DDX11 expression. Forced expression DDX11 reversed the anticancer effects of YY1 silencing on OSCC cells. DDX11 has tumor-promoting function in OSCC and is transcriptionally regulated by YY1, indicating that DDX11 may serve as a potential target for the OSCC treatment.

Subthreshold Micropulse Laser Versus Oral Spironolactone in Chronic Central Serous Chorioretinopathy: A Quasi-Randomized Controlled Trial.

Purpose: To compare the efficacy and safety of subthreshold micropulse laser (SML) and spironolactone therapy for treating chronic central serous chorioretinopathy (CSC). Methods: This was a quasi-randomized controlled trial. Eligible patients were quasi-randomized at a 1:1 ratio to receive SML or oral spironolactone and were assessed at 3 months after treatment. Results: A total of 84 patients (90 eyes) were randomly assigned to receive SML (n = 45) or spironolactone (n = 39) initially. At last follow-up, 59.5% of patients in the SML group had complete resolution of subretinal fluid (SRF) compared to 43.6% in spironolactone group (P = 0.362). The mean visual acuity did not significantly improve between the two groups (0.38 ± 0.44 vs. 0.43 ± 0.43 logMAR). The central retinal thickness was decreased from 335.06 ± 120.25 µm to 222.15 ± 94.90 µm in the SML group and from 308.02 ± 90.69 µm to 257.27 ± 102.28 µm in the spironolactone group. After treatment, subfoveal choroidal thickness, total choroidal area, and stromal and luminal choroidal area were significantly lower in the spironolactone group as compared to the SML group. During the entire visit, the recurrence rate of SRF was 9.1% in the SML group compared to 35.3% in the spironolactone group. Slight adverse events occurred more frequently in the spironolactone group (0% vs. 16%). Conclusions: Both SML and oral spironolactone were effective and safe treatments to ameliorate retinal anatomical structures for chronic CSC. A lower recurrence rate and fewer adverse effects were observed in the SML group, and better choroidal structure recovery was seen in the spironolactone group. Translational Relevance: The investigation of SML and oral spironolactone may inform evidence-based clinical decisions for chronic CSC patients.

Ultra-Widefield Imaging of Bilateral Streaky Multifocal Choroiditis in a 12-Year-Old Boy.

This case report describes a diagnosis of streaky multifocal choroiditis in a boy who presented with distorted vision in his left eye for 3 years.

Association between central serous chorioretinopathy and Helicobacter pylori infection: a systematic review and Meta-analysis.

AIM: To investigate the association between central serous chorioretinopathy (CSC) and Helicobacter pylori (Hp) by summarizing all available evidence. METHODS: The Scopus, Embase, EBSCO, PubMed, Web of Science, and Cochrane Library databases for all relevant studies published from inception to October 2022 were searched, and manually searched for relevant reference lists as a supplement. Studies investigating the association between CSC and Hp infection were included. Finally, 8 case-control studies were included in the Meta-analysis after study selection. RESULTS: The results showed no significant correlation between Hp infection and CSC [odds ratio (OR) 1.89, 95% confidential interval (CI) 0.58-6.15, I 2=96%, P=0.29]. After subgroup analysis based on the degree of development of the study (developing/developed countries), it was found that the results of the two subgroups were the same as the whole, and no significant difference between the two subgroups existed. Meta-regression showed that the effect of sample size on heterogeneity among studies was more prominent (P<0.01, adjusted R 2=89.72%), which can explain 89.72% of the sources of heterogeneity. CONCLUSION: This Meta-analysis reveals no significant correlation between Hp infection and CSC, which still warrants further well-designed extensive sample studies to reach a more reliable conclusion and promote a better understanding of the treatment of CSC.

Effect of Individualized Ocular Refraction Customization Spectacle Lens Wear on Visual Performance in Myopic Chinese Children.

Purpose: Individualized ocular refraction customization (IORC) lenses can be individually adjusted depending on the initial relative peripheral refraction to determine the myopic defocus (MD). We aimed to compare visual performance of children wearing IORC lenses with different amounts of MD to determine whether higher MD resulted in greater visual compromise. Methods: This study included 184 myopic children aged eight to 12 years, and 172 completed the trial. The participants were randomly assigned to wear IORC lenses with low (IORC-L, 2.50 D), medium (IORC-M, 3.50 D), or high (IORC-H, 4.50 D) MD or single-vision spectacle lenses (SVL). Distance and near best-corrected visual acuity (BCVA), contrast sensitivity function (CSF) and questionnaires were evaluated at baseline and after six and 12 months. Results: CSF over all frequencies and distance and near BCVA were not affected by lens design (all P > 0.05). The SVL group outperformed the three IORC lens groups in terms of ghosting images at baseline, and IORC-H and IORC-M groups outperformed IORC-L group (all P < 0.001); however, no differences were observed at the six- or 12-month visit. There were no significant differences among the four groups for any other subjective variables at any of the follow-up visits regarding vision clarity, vision stability, eyestrain, dizziness, headache, or overall vision satisfaction (all P > 0.05). Conclusions: The IORC lenses with an actual MD of 4.50 D provided acceptable objective and subjective visual performance and were well tolerated by children. Translational Relevance: IORC lenses with an actual MD of 4.50 D provided acceptable visual performance.

Exploring laser-induced acute and chronic retinal vein occlusion mouse models: Development, temporal in vivo imaging, and application perspectives.

Photodynamic venous occlusion is a commonly accepted method for establishing mouse models of retinal vein occlusion (RVO). However, existing model parameters do not distinguish between acute and chronic RVO subtypes. Large variations in laser energy seem to correlate with fluctuating retinopathy severity and high rates of venous recanalization during the acute phase, along with the variable levels of retinal perfusion during the chronic phase. After optimizing the modeling procedure and defining success and exclusion criteria, laser energy groups of 80mW, 100mW, and 120mW were established. Multimodal imaging confirmed that higher energy levels increased the incidence of retinal cystoid edema and intraretinal hemorrhage, exacerbated the severity of exudative retinal detachment, and reduced the venous recanalization rate. For the acute model, 100mW was considered an appropriate parameter for balancing moderate retinopathy and venous recanalization. Continuous imaging follow-up revealed that day 1 after RVO was the optimal observation point for peaking of retinal thickness and intensive occurrence of retinal cystic edema and intraretinal hemorrhage. After excluding the influence of venous recanalization on retinal thickness, acute retinal edema demonstrated a positive response to standard anti-vascular endothelial growth factor therapy, validating the clinical relevance of the acute RVO model for further study in pathogenic mechanisms and therapeutic efficacy. For the chronic model, the 120mW parameter with the lowest venous recanalization rate was applied, accompanied by an increase in both photocoagulation shots and range to ensure sustained vein occlusion. Imaging follow-up clarified non-ischemic retinopathy characterized by tortuosity and dilation of the distal end, branches, and adjacent veins of the occluded vein. These morphological changes are quantifiable and could be combined with electrophysiological functional assessment for treatment effectiveness evaluation. Moreover, the stable state of venous occlusion may facilitate investigations into response and compensation mechanisms under conditions of chronic retinal hypoperfusion.

Vitrectomy for a traumatic macular hole caused by cosmetic laser in a beauty salon: A case report.

Background: The Nd:YAG laser is widely used in various aspects of work and life. Currently, it has become a popular cosmetic technique in beauty salons. The laser can be dangerous when it flashes into people's eyes. Case presentation: A 34-year-old female sustained a 1064-nm Q-switched Nd:YAG laser injury to her left eye. One month after the injury, she presented to our clinic with best-corrected visual acuity (BCVA) of 20/250 and a full-thickness macular hole on the optical coherence tomography (OCT). The patient received pars plana vitrectomy, internal limiting membrane peeling and sterile air injection 3 months after the injury. OCT showed closure of the hole 9 days postoperatively. After a 3-month follow-up, her BCVA improved to 20/100. Conclusions: This case report comprehensively introduces the whole progression of a cosmetic laser-induced macular hole from formation to recovery. Due to the potential threats of the laser and its irreversible damage to the retina and choroid, sufficient education should be given before performing any laser devices, especially those without professional knowledge.

BMSC Alleviates Dry Eye by Inhibiting the ROS-NLRP3-IL-1ß Signaling Axis by Reducing Inflammation Levels.

PURPOSE: Bone marrow mesenchymal stem cells (BMSC) have multiple biological functions and are widely involved in regulating inflammatory diseases, tissue repair and regeneration. However, the mechanism of their action in dry eye disease (DED) is currently unclear. The purpose of this study was to investigate the effect of BMSCs in the treatment of dry eye mice and to explore its specific therapeutic mechanism. METHODS: Mouse corneal epithelial cells (MCECs) were treated with 500 mOsM sodium chloride hypertonic solution to induce a DED cell model. The dry eye animal model was constructed by adding 5 µL 0.2% benzalkonium chloride solution to mouse eyes. Western blotting was used to detect the expression of related proteins, and flow cytometry, enzyme-linked immunosorbent assay (ELISA), terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining, hematoxylin-eosin (HE) staining, and periodic acid schiff (PAS) staining were used to detect cell and eye tissue damage. RESULTS: The experimental results showed that BMSCs can reduce the levels of reactive oxygen species (ROS) and inflammatory factors in MCECs, promote cell proliferation, inhibit cell apoptosis, improve the integrity of the corneal epithelial layer in vivo, promote an increase in the number of goblet cells, and alleviate DED. Further exploration of the molecular mechanism of BMSCs treatment revealed that BMSCs alleviate the progression of DED by inhibiting the ROS-NLRP3-IL-1ß signaling pathway. CONCLUSION: BMSCs inhibit ROS-NLRP3-IL-1ß signaling axis, reducing inflammation levels and alleviating dry eye symptoms. These findings provide new ideas and a basis for the treatment of DED and provide an experimental basis for further research on the application value of BMSCs in alleviating DED.

Multimodal imaging shows acute multilayered retinal hemorrhages in heatstroke-a rare case report.

Background: Heatstroke is a life-threatening disease clinically characterized by central nervous system dysfunction, multiorgan failure, and extreme hyperthermia. There are no reports about eye involvement in heat stroke. Here, we report a rare case of multilayered retinal hemorrhages in a patient with heatstroke. Case presentation: A 55-year-old male with a one-month history of blurry vision in both eyes presented at our department after suffering from heatstroke. His visual acuity was 5/20 OD and 10/20 OS. Fundus examination revealed retinal hemorrhages in both eyes. Fundus autofluorescence images and near-infrared reflectance images revealed well-defined retinal lesions. Optical coherence tomography helped to accurately locate the different layers of the lesions, including the nerve fiber layer, sub-inner limiting membrane, outer plexiform layer, ellipsoid zone and Henle fiber layer hemorrhages. We followed up with the patient for 8 months. At the last follow-up, his visual acuity was 20/20 in both eyes, and fundus examination showed that retinal hemorrhages were almost completely absorbed. Conclusion: To our knowledge, this is the first report on multilayered retinal hemorrhages secondary to heat stroke. Intraretinal and preretinal hemorrhages can gradually resolve, and the patient's vision will improve with the absorption of the retinal hemorrhages. Multimodal imaging may help to reveal additional details about retinal lesions and monitor the course of the disease.

ITPR2 Mediated Calcium Homeostasis in Oligodendrocytes is Essential for Myelination and Involved in Depressive-Like Behavior in Adolescent Mice.

Ca2+ signaling is essential for oligodendrocyte (OL) development and myelin formation. Inositol 1,4,5-trisphosphate receptor type 2 (ITPR2) is an endoplasmic reticulum calcium channel and shows stage-dependent high levels in postmitotic oligodendrocyte precursor cells (OPCs). The role and potential mechanism of ITPR2 in OLs remain unclear. In this study, it is revealed that loss of Itpr2 in OLs disturbs Ca2+ homeostasis and inhibits myelination in adolescent mice. Animals with OL-specific deletion of Itpr2 exhibit anxiety/depressive-like behaviors and manifest with interrupted OPC proliferation, leading to fewer mature OLs in the brain. Detailed transcriptome profiling and signal pathway analysis suggest that MAPK/ERK-CDK6/cyclin D1 axis underlies the interfered cell cycle progression in Itpr2 ablated OPCs. Besides, blocking MAPK/ERK pathway significantly improves the delayed OPC differentiation and myelination in Itpr2 mutant. Notably, the resting [Ca2+]i is increased in Itpr2 ablated OPCs, with the elevation of several plasma calcium channels. Antagonists against these plasma calcium channels can normalize the resting [Ca2+]i level and enhance lineage progression in Itpr2-ablated OPCs. Together, the findings reveal novel insights for calcium homeostasis in manipulating developmental transition from OPCs to pre-OLs; additionally, the involvement of OLs-originated ITPR2 in depressive behaviors provides new therapeutic strategies to alleviate myelin-associated psychiatric disorders.

Delayed macular hole secondary to Terson syndrome: a case report and literature review.

Terson syndrome refers to intraocular haemorrhage that occurs due to subarachnoid bleeding associated with an acute increase in intracranial pressure. No previous study has reported a delayed macular hole (MH) secondary to Terson syndrome. A 17-year-old boy visited our department and presented with vitreous bleeding and a history of subarachnoid haemorrhage. Sub-internal limiting membrane (ILM) haemorrhage with ILM detachment and intraretinal haemorrhage were detected during pars plana vitrectomy. Additionally, a delayed MH was detected 1 week after the surgery. There was no sign of MH closure during a 2-month follow-up. Subsequently, an MH massage was performed to close the MH. Our findings suggest that a delayed MH can occur secondary to Terson syndrome. Elevated hydrodynamic pressure and hydrostatic pressure, which are caused by sub-ILM and intraretinal haemorrhages of the fovea, contribute to the formation of an MH. Additionally, ILM peeling may cause damage to the macula and facilitate the formation of MHs. Although the MH may close by itself, early surgical intervention is recommended when there is no sign that the MH will close spontaneously because a prolonged MH can lead to retinal damage.

Efficacy and Predictive Factors of Oral Spironolactone Treatment in Chronic Central Serous Chorioretinopathy.

Purpose: To evaluate the efficacy of spironolactone in the treatment of chronic central serous chorioretinopathy (CSC) and identify imaging characteristics that can predict the benefit of spironolactone treatment. Methods: Patients with chronic CSC were treated with spironolactone (20 mg/tid) and followed for 6 months. The primary outcome measure was complete resolution of the subretinal fluid (SRF), and the best-corrected visual acuity (BCVA), the SRF area, the central macular thickness (CMT), the subfoveal choroidal thickness (SFCT), and the density of the choriocapillaris vessel and adverse events were secondary outcome measures. Patients who presented complete resolution of SRF were included in the responder group and the other patients who had moderate or no resolution were included in the nonresponder group. Imaging characteristic comparisons between the responder and nonresponder groups were performed with regression analyses to identify factors that are predictive of a good response to treatment. Results: Forty-two eyes of 42 patients with a mean age of 46.06 ± 6.66 years were included. A total of 57.1% of the patients achieved a complete resolution of SRF. The mean SRF area, CMT, and SFCT decreased significantly (all P < 0.05) throughout the follow-up period and BCVA improved slightly (P > 0.05). The vascular density of the choriocapillaris of the fellow eyes did not vary significantly during treatment. Logistic regression analysis revealed that SFCT (P=0.002) and the intact ellipsoid zone (P=0.001) were correlated with disease resolution. A relatively higher baseline SFCT was a predictive factor associated with a good response to treatment according to multivariate analysis. Conclusions: This study suggested that oral spironolactone could be an effective and safe therapy for chronic CSC patients. Eyes with a higher baseline SFCT and intact ellipsoid zone could have a good response. These parameters are an important prognostic marker.

The complement system and diabetic retinopathy.

Diabetic retinopathy (DR) is one of the common microvascular complications of diabetes mellitus and is the main cause of visual impairment in diabetic patients. The pathogenesis of DR is still unclear. The complement system, as an important component of the innate immune system in addition to defending against the invasion of foreign microorganisms, is involved in the occurrence and development of DR through 3 widely recognized complement activation pathways, the complement regulatory system, and many other pathways. Molecules such as C3a, C5a, and membrane attacking complex, as important molecules of the complement system, are involved in the pathologenesus of DR, either through direct damaging effects or by activating cells (microglia, macroglia, etc.) in the retinal microenvironment to contribute to the pathological damage of DR indirectly. We review the integral association of the complement system and DR to further understand the pathogenesis of DR and possibly provide a new strategy for itstreatment.

Influence of Ventilation on Formation and Growth of 1-20 nm Particles via Ozone-Human Chemistry.

Ozone reaction with human surfaces is an important source of ultrafine particles indoors. However, 1-20 nm particles generated from ozone-human chemistry, which mark the first step of particle formation and growth, remain understudied. Ventilation and indoor air movement could have important implications for these processes. Therefore, in a controlled-climate chamber, we measured ultrafine particles initiated from ozone-human chemistry and their dependence on the air change rate (ACR, 0.5, 1.5, and 3 h-1) and operation of mixing fans (on and off). Concurrently, we measured volatile organic compounds (VOCs) and explored the correlation between particles and gas-phase products. At 25-30 ppb ozone levels, humans generated 0.2-7.7 × 1012 of 1-3 nm, 0-7.2 × 1012 of 3-10 nm, and 0-1.3 × 1012 of 10-20 nm particles per person per hour depending on the ACR and mixing fan operation. Size-dependent particle growth and formation rates increased with higher ACR. The operation of mixing fans suppressed the particle formation and growth, owing to enhanced surface deposition of the newly formed particles and their precursors. Correlation analyses revealed complex interactions between the particles and VOCs initiated by ozone-human chemistry. The results imply that ventilation and indoor air movement may have a more significant influence on particle dynamics and fate relative to indoor chemistry.

Physiology or Psychology: What Drives Human Emissions of Carbon Dioxide and Ammonia?

Humans are the primary sources of CO2 and NH3 indoors. Their emission rates may be influenced by human physiological and psychological status. This study investigated the impact of physiological and psychological engagements on the human emissions of CO2 and NH3. In a climate chamber, we measured CO2 and NH3 emissions from participants performing physical activities (walking and running at metabolic rates of 2.5 and 5 met, respectively) and psychological stimuli (meditation and cognitive tasks). Participants' physiological responses were recorded, including the skin temperature, electrodermal activity (EDA), and heart rate, and then analyzed for their relationship with CO2 and NH3 emissions. The results showed that physiological engagement considerably elevated per-person CO2 emission rates from 19.6 (seated) to 46.9 (2.5 met) and 115.4 L/h (5 met) and NH3 emission rates from 2.7 to 5.1 and 8.3 mg/h, respectively. CO2 emissions reduced when participants stopped running, whereas NH3 emissions continued to increase owing to their distinct emission mechanisms. Psychological engagement did not significantly alter participants' emissions of CO2 and NH3. Regression analysis revealed that CO2 emissions were predominantly correlated with heart rate, whereas NH3 emissions were mainly associated with skin temperature and EDA. These findings contribute to a deeper understanding of human metabolic emissions of CO2 and NH3.

Applications of deep learning for detecting ophthalmic diseases with ultrawide-field fundus images.

AIM: To summarize the application of deep learning in detecting ophthalmic disease with ultrawide-field fundus images and analyze the advantages, limitations, and possible solutions common to all tasks. METHODS: We searched three academic databases, including PubMed, Web of Science, and Ovid, with the date of August 2022. We matched and screened according to the target keywords and publication year and retrieved a total of 4358 research papers according to the keywords, of which 23 studies were retrieved on applying deep learning in diagnosing ophthalmic disease with ultrawide-field images. RESULTS: Deep learning in ultrawide-field images can detect various ophthalmic diseases and achieve great performance, including diabetic retinopathy, glaucoma, age-related macular degeneration, retinal vein occlusions, retinal detachment, and other peripheral retinal diseases. Compared to fundus images, the ultrawide-field fundus scanning laser ophthalmoscopy enables the capture of the ocular fundus up to 200° in a single exposure, which can observe more areas of the retina. CONCLUSION: The combination of ultrawide-field fundus images and artificial intelligence will achieve great performance in diagnosing multiple ophthalmic diseases in the future.

Effect of hot electron induced charge transfer generated by surface plasmon resonance on Ag@Au/ITO/PNTP systems.

The present study discusses the fabrication of a bimetallic material consisting of silver nanorods and gold nanospheres (designated Ag@Au), and its surface modification with 4-nitrothiophenol (PNTP) after deposition on an indium tin oxide (ITO) glass sheet, followed by laser irradiation at various wavelengths. The results indicate that the reduction of PNTP is more complete under irradiation at 532 nm due to the surface plasmon resonance (SPR) effects of the gold and silver nanomaterials. Moreover, the surface enhanced Raman scattering (SERS) of the PNTP adsorbed on the Ag@Au/ITO is found to be significantly stronger than that of PNTP adsorbed on Ag@Au alone, due to charge transfer (CT) at the interface. In addition, the SERS enhancement effect of the PNTP molecules on the Ag@Au/ITO substrate is optimal under 532 nm laser irradiation due to the hot electron-induced CT generated by the SPR effect. Thus, the system constructed herein combines the effects of SPR and CT, thereby assisting in a further understanding of the enhancement mechanism of SERS and, hence, the further development SERS research in metal-semiconductor-molecular systems.

Broadleaf trees switch from phosphorus to nitrogen limitation at lower latitudes than conifers.

Nitrogen (N) and phosphorus (P) are common limiting elements for terrestrial ecosystem productivity. Understanding N-P nutrient limitations patterns is crucial for comprehending variations in productivity within terrestrial ecosystems. However, the global nutrient limitation patterns of woody plants, that dominate forests, especially across different functional types, remain unclear. Here, we compiled a global dataset of leaf N and P concentrations and resorption efficiency (NRE and PRE) to explore latitudinal nutrient limitation patterns in natural woody plants and their environmental drivers. Based on published fertilization experiments, we compiled another global woody plant nutrient database to validate such identified patterns. The results showed that with increasing latitude, the relative P vs N resorption efficiency (PRE minus NRE) and the N and P ratio decreased in woody plant leaves, suggesting that the nutrient status of woody plants shifts from P to N limitation as latitude increases, with a switching point of N-P balance occurring at mid-latitudes (42.9°-43.6°). Different functional types exhibited similar trends, but with different switching latitudes of N vs P limitation. Due to the lower N uptake capacity of broadleaves than conifers, broadleaves reached N-P balance at lower latitudes (39.6°-43.3°) than conifers (57.1°-59.1°) in both hemispheres. Data from fertilization experiments successfully identified 81 % of the N limitation cases and 91 % of the P limitation cases identified using the first database. N and P limitation cases for conifers and broadleaves were also well identified separately. The latitudinal nutrient limitations in global woody plants are primarily shaped by climate and soil. Our study demonstrates the switching latitudes of N vs P limitation which varies between broadleaves and conifers. These findings enhance our understanding of plant nutrient dynamics in global climate change and aid in refining forest management.