Mesenchymal stem cells(MSCs)play a crucial role in tissue repair and regeneration,and the extracellular vesicle(EV)released by them holds great promise for applications in clinical biomarkers,vaccines,and drug delivery.However,MSCs-derived EV(MSCs-EV)face challenges such as low pro-duction yield,poor retention,and targeted delivery issues.There-fore,engineering MSCs-EV to enhance their performance and en-able visual research has become a hot topic.Curcumin(CUR),an active component in traditional chinese medicine,exhibits pharmacological effects but has limited bioavailability.Using MSCs-EV as a carrier for CUR delivery can address its solubility and bioavailability challenges.This article reviews the drug loading methods,engineering strategies of MSCs-EV,and their important applications in the delivery and treatment of CUR for cartilage injury diseases.It provides a basis for the clinical ap-plication of engineered MSCs-EV in CUR delivery for cartilage repair,offering potential solutions to the challenges in cartilage tissue repair.

Mesenchymal stem cells(MSCs)play a crucial role in tissue repair and regeneration,and the extracellular vesicle(EV)released by them holds great promise for applications in clinical biomarkers,vaccines,and drug delivery.However,MSCs-derived EV(MSCs-EV)face challenges such as low pro-duction yield,poor retention,and targeted delivery issues.There-fore,engineering MSCs-EV to enhance their performance and en-able visual research has become a hot topic.Curcumin(CUR),an active component in traditional chinese medicine,exhibits pharmacological effects but has limited bioavailability.Using MSCs-EV as a carrier for CUR delivery can address its solubility and bioavailability challenges.This article reviews the drug loading methods,engineering strategies of MSCs-EV,and their important applications in the delivery and treatment of CUR for cartilage injury diseases.It provides a basis for the clinical ap-plication of engineered MSCs-EV in CUR delivery for cartilage repair,offering potential solutions to the challenges in cartilage tissue repair.

Global procurement of health products is an important way for multilateral organizations in the health field to perform their functions.As one of the most important multilateral organizations in the global health field today,the Global Fund to Fight AIDS,Tuberculosis and Malaria occupies a huge share of the global procurement market for health products.This article introduces in detail the procurement methods of the Global Fund and the quality standards of its procured products;also it describes and analyzes the total amount of funds procured by the Global Fund,the types of procured health products,the main supply countries and their changing trends over time.Corresponding policy suggestions therefore are proposed for China to better participate in the governance of global health and for Chinese related companies to enter the international procurement market.

United Nations(UN)agencies are key actors in global procurement of health products,with the United Nations Children's Fund(UNICEF)currently accounting for the largest share of UN procurement expenditures.This study developed a conceptual framework to analyze the processes of UN's global procurement for health products.Based on this framework,the study analyzed the mechanisms and key characteristics of UN procurement practices,identified potential challenges faced by Chinese products and suppliers seeking to engage with the UN's global procurement.The findings indicate a steady increase in the volume of Chinese products procured and their alignment with the UN's sustainable procurement policies.However,Chinese suppliers still face notable barriers,including gaps in technical standards,bidding and contracting capacities,and price competitiveness.In addition,the strategic compliance capabilities of Chinese suppliers and products,such as the ability to offer strategically valuable products and build long-term partnership,remains limited.Based on this,the study recommends that China enhance its participation and influence in the UN health procurements by stabilizing the production capacity,promoting knowledge-sharing among suppliers to enhance their engagement capabilities,and improving the long-term strategic competitiveness of Chinese enterprises in the global market.

United Nations(UN)agencies are key actors in global procurement of health products,with the United Nations Children's Fund(UNICEF)currently accounting for the largest share of UN procurement expenditures.This study developed a conceptual framework to analyze the processes of UN's global procurement for health products.Based on this framework,the study analyzed the mechanisms and key characteristics of UN procurement practices,identified potential challenges faced by Chinese products and suppliers seeking to engage with the UN's global procurement.The findings indicate a steady increase in the volume of Chinese products procured and their alignment with the UN's sustainable procurement policies.However,Chinese suppliers still face notable barriers,including gaps in technical standards,bidding and contracting capacities,and price competitiveness.In addition,the strategic compliance capabilities of Chinese suppliers and products,such as the ability to offer strategically valuable products and build long-term partnership,remains limited.Based on this,the study recommends that China enhance its participation and influence in the UN health procurements by stabilizing the production capacity,promoting knowledge-sharing among suppliers to enhance their engagement capabilities,and improving the long-term strategic competitiveness of Chinese enterprises in the global market.

Global procurement of health products is an important way for multilateral organizations in the health field to perform their functions.As one of the most important multilateral organizations in the global health field today,the Global Fund to Fight AIDS,Tuberculosis and Malaria occupies a huge share of the global procurement market for health products.This article introduces in detail the procurement methods of the Global Fund and the quality standards of its procured products;also it describes and analyzes the total amount of funds procured by the Global Fund,the types of procured health products,the main supply countries and their changing trends over time.Corresponding policy suggestions therefore are proposed for China to better participate in the governance of global health and for Chinese related companies to enter the international procurement market.

Objective To construct an aptamer-functionalized carboxylated graphene oxide(CGO)fluo-rescent sensor to achieve highly sensitive and specific detection of ketamine(KET)and its metabolite norketamine(NK)using an aptamer capable of simultaneously recognizing KET and NK.Methods A specific aptamer for simultaneous recognition of KET and NK was screened using graphene oxide-sys-tematic evolution of ligand by exponential enrichment(GO-SELEX)and molecular docking tech-niques.The aptamer,labeled with Cy5 fluorescence,was chemically conjugated to CGO to construct an aptamer-functionalized CGO fluorescent sensor.By optimizing detection conditions,including the mass concentration of CGO,aptamer concentration,reaction temperature,and incubation time,quantita-tive analysis of the target analytes was achieved using the ratio of fluorescence intensity changes be-fore and after target addition.The stability of the sensor in biological matrices was evaluated by moni-toring fluorescence intensity changes over incubation time in blank blood and urine,in comparison with the traditional physical adsorption-based CGO fluorescent sensor.Spiked recovery experiments in blank blood and urine were conducted to compare performance with that of HPLC-MS/MS.Results A specific aptamer A5 was selected and chemically conjugated with CGO to construct the aptamer-functionalized CGO fluorescent sensor.Under optimized conditions,the proposed fluorescent sensor ex-hibited a linear detection range of 1.0-5.0 ng/mL for KET,with a limit of detection(LOD)of 0.86 ng/mL;while for NK,the linear detection range was 1.0-5.0 ng/mL,with an LOD of 0.70 ng/mL.Com-pared with the CGO fluorescent sensor constructed via physical adsorption,this sensor demonstrated greater stability in blood and urine.The spiked recovery rates of KET and NK in blank blood and urine ranged from 81.50%to 110.03%,exhibiting detection performance comparable to that of HPLC-MS/MS.Conclusion The aptamer screening method offers a novel approach for selecting aptamers tar-geting drugs and their metabolites.The constructed aptamer-functionalized CGO fluorescent sensor pro-vides an efficient and reliable strategy for the high-performance detection of KET and NK.

Ovarian tumor (OT) is the most lethal form of gynecologic malignancy, with minimal improvements in patient outcomes over the past several decades. Metastasis is the leading cause of ovarian cancer-related deaths, yet the underlying mechanisms remain poorly understood. Psychological stress is known to activate the glucocorticoid receptor (NR3C1), a factor associated with poor prognosis in OT patients. However, the precise mechanisms linking NR3C1 signaling and metastasis have yet to be fully elucidated. In this study, we demonstrate that chronic restraint stress accelerates epithelial-mesenchymal transition (EMT) and metastasis in OT through an NR3C1-dependent mechanism involving nuclear protein 1 (NUPR1). Mechanistically, NR3C1 directly regulates the transcription of NUPR1, which in turn increases the expression of snail family transcriptional repressor 2 (SNAI2), a key driver of EMT. Clinically, elevated NR3C1 positively correlates with NUPR1 expression in OT patients, and both are positively associated with poorer prognosis. Overall, our study identified the NR3C1/NUPR1 axis as a critical regulatory pathway in psychological stress-induced OT metastasis, suggesting a potential therapeutic target for intervention in OT metastasis.

Background and purpose:Human epidermal growth factor receptor 2(HER2)serves as one of the paramount drivers of breast cancer metastasis,with roughly 20%-30%of breast cancer patients exhibiting high expression of HER2.The expression level of HER2 is regulatable at multiple molecular levels and determines the metastatic potential of breast cancer cells;however,the manner in which HER2 expression is modulated at the mRNA level remains ambiguous.Circ-0007766 is a circRNA originated from the coding gene ERBB2 for HER2,and whether circ-0007766 can regulate HER2 expression via the ceRNA mechanism has not been reported.This study aimed to analyze whether circ-0007766 acts as a miR-1972 sponge to promote breast cancer cell migration and invasion via upregulation of HER2 expression.Methods:In this study,a high-throughput circRNA chip was employed to screen for circRNAs that exhibited highly specific expression in HER2-positive breast cancer cells.RNA fluorescence in situ hybridization(FISH)was utilized to detect the subcellular localization of circ-0007766.The BaseScope experiment was conducted to analyze the expression level of circ-0007766 in breast cancer tissues and its clinical diagnostic significance.Breast cancer cell models with overexpression and knockdown of circ-0007766 were constructed by transfecting cloning plasmids and siRNA in vitro.The effect of circ-0007766 on the migration and invasion of breast cancer cells was assessed using transwell migration and invasion experiments,and the migration and invasion abilities of MDA-MB-231 and SK-BR-3 cells were measured.Additionally,it was evaluated whether circ-0007766 could promote the migration and invasion of breast cancer cells through miR-1972.A dual luciferase reporter gene assay was used to verify whether circ-0007766 could regulate HER2 expression by binding to miR-1972.The direct interaction between circ-0007766 and miR-1972 was further verified through the RAP experiment.RIP detection was performed in MDA-MB-231 cells,and the relative 3'UTR of HER2 mRNA was measured by real-time fluorescence quantitative polymerase chain reaction(RTFQ-PCR).Western blot was used to detect the protein expressions.Results:Circ-0007766 was conspicuously highly expressed in HER2-positive breast cancer cells and distributed in both the cytoplasm and nucleus of cells,with the preponderance being in the cytoplasm.The expression level of circ-0007766 was strikingly higher in breast cancer tissues than in para-cancerous tissues.The expression of circ-0007766 was significantly elevated in HER2-positive breast cancer samples compared with HER2-negative samples.The overexpression(knockdown)of circ-0007766 in HER2-negative breast cancer cells(in HER2-positive breast cancer cells)was capable of promoting(inhibiting)the migration and invasion of breast cancer cells.Circ-0007766 directly bound to miR-1972,which inhibited breast cancer cell migration and invasion,thereby forming an endogenous competitive RNA(ceRNA)regulatory network and impeding the downregulation of HER2 mRNA and protein expression mediated by miR-1972.Circ-0007766 could potentiate the inhibitory effect of miR-1972 on HER2-mediated breast cancer cell migration and invasion that was negatively regulated by miR-1972.CircRNAs sequestered miRNAs to function as ceRNAs,thereby regulating gene expression at both the transcriptional and translational levels.Finally,we discovered that the expressions of circ-0007766 and HER2 were positively correlated in breast cancer cell and tissue samples,while the expression levels of miR-1972 and HER2 were negatively correlated.Circ-0007766 could specifically target miR-1972 to hinder its regulatory effect on HER2 expression.Conclusion:This study discovers that circ-0007766 facilitates the migration and invasion of breast cancer cells via the miR-1972/HER2 signal axis,offering a novel biomarker and potential therapeutic target for patients with metastatic HER2-positive breast cancer.

AIM:To explore the use of attention mechanism and Pix2Pix generative adversarial network to predict the postoperative corneal topography of age-related cataract patients undergone femtosecond laser arcuate keratotomy.METHODS:In this retrospective case series study, the 210 preoperative and postoperative corneal topographies from 87 age-related cataract patients(105 eyes)undergoing femtosecond laser arcuate keratotomy at Shanxi Eye Hospital between March 2018 and March 2020 were selected and divided into a training set(180)and a test set(30)for model training and testing. The peak signal-to-noise ratio(PSNR), structural similarity(SSIM)and Alpins astigmatism vector analysis were used to compare the accuracy of postoperative corneal topography prediction under different attention mechanisms.RESULTS:The model based on attention mechanism and Pix2Pix network can predict postoperative corneal topography, among which the model based on Self-Attention mechanism has the best prediction effect, with PSNR and SSIM reaching 16.048 and 0.7661, respectively. There were no statistically significant differences in the difference vector, difference vector axis position, surgically induced astigmatism, and correction index between real and generated corneal topography on the 3mm and 5mm rings(all P>0.05).CONCLUSION:Based on the Self-Attention mechanism and Pix2Pix network, the postoperative corneal topography can be well predicted, which can provide reference for the surgical planning and postoperative effects of ophthalmic clinicians.