Topological spin texture in the pseudogap phase of a high-Tc superconductor.

An outstanding challenge in condensed-matter-physics research over the past three decades has been to understand the pseudogap (PG) phenomenon of the high-transition-temperature (high-Tc) copper oxides. A variety of experiments have indicated a symmetry-broken state below the characteristic temperature T* (refs. 1-8). Among them, although the optical study5 indicated the mesoscopic domains to be small, all these experiments lack nanometre-scale spatial resolution, and the microscopic order parameter has so far remained elusive. Here we report, to our knowledge, the first direct observation of topological spin texture in an underdoped cuprate, YBa2Cu3O6.5, in the PG state, using Lorentz transmission electron microscopy (LTEM). The spin texture features vortex-like magnetization density in the CuO2 sheets, with a relatively large length scale of about 100 nm. We identify the phase-diagram region in which the topological spin texture exists and demonstrate the ortho-II oxygen order and suitable sample thickness to be crucial for its observation by our technique. We also discuss an intriguing interplay observed among the topological spin texture, PG state, charge order and superconductivity.

Controllable Synthesis of Highly Symmetrical Streamlined Structure for Wideband Microwave Absorption.

Highly symmetrical and streamlined nanostructures possessing unique electron scattering, electron-phonon coupling, and electron confinement characteristics have attracted a lot of attention. However, the controllable synthesis of such a nanostructure with regulated shapes and sizes remains a huge challenge. In this work, a peanut-like MnO@C structure, assembled by two core-shell nanosphere is developed via a facile hydrogen ion concentration regulation strategy. Off-axis electron holography technique, charge reconstruction, and COMSOL Multiphysics simulation jointly reveal the unique electronic distribution and confirm its higher dielectric sensitive ability, which can be used as microwave absorption to deal with currently electromagnetic pollution. The results reveal that the peanut-like core-shell MnO@C exhibits great wideband properties with effective absorption bandwidth of 6.6 GHz, covering 10.8-17.2 GHz band. Inspired by this structure-induced sensitively dielectric behavior, promoting the development of symmetrical and streamlined nanostructure would be attractive for many other promising applications in the future, such as piezoelectric material and supercapacitor and electromagnetic shielding.

Construction of Switch Modules for CAR-T Cell Treatment Using a Site-Specific Conjugation System.

Chimeric antigen receptor T-cell (CAR-T cell) therapy has become a promising treatment option for B-cell hematological tumors. However, few optional target antigens and disease relapse due to loss of target antigens limit the broad clinical applicability of CAR-T cells. Here, we conjugated an antibody (Ab) fusion protein, consisting of an Ab domain and a SpyCatcher domain, with the FITC-SpyTag (FITC-ST) peptide to form a bispecific safety switch module using a site-specific conjugation system. We applied the safety switch module to target CD19, PDL1, or Her2-expressing tumor cells by constructing FMC63 (anti-CD19), antiPDL1, or ZHER (anti-Her2)-FITC-ST, respectively. Those switch modules significantly improved the cytotoxic effects of anti-FITC CAR-T cells on tumor cells. Additionally, we obtained the purified CD8+ T cells by optimizing a shorter version of the CD8-binding aptamer to generate anti-FITC CD8-CAR-T cells, which combined with the CD4-FITC-ST switch module (anti-CD4) to eliminate the CD4-positive tumor cells in vitro and in vivo. Overall, we established a novel safety switch module by site-specific conjugation to enhance the antitumor function of universal CAR-T cells, thereby expanding the application scope of CAR-T therapy and improving its safety and efficacy.

Construction of Covalent Triazine Frameworks with Electronic Donor-Acceptor System for Efficient Photocatalytic C-H Hydroxylation of Imidazole[1,2-α]Pyridine Derivatives.

Covalent triazine frameworks (CTFs) are promising heterogeneous photocatalyst candidates owing to their excellent stability, conjugacy, and tunability. In this study, a series of CTFs decorated with different substituents (H, MeO, and F) were synthesised and utilised as photocatalysts for C-H activation reactions. The corresponding optoelectronic properties could be precisely regulated by the electronic effects of different substituents in the nanopore channels of the CTFs; these CTFs were effective photocatalysts for C-H activation in organic synthesis due to their unique structures and optoelectronic properties. Methoxy-substituted CTF (MeO-CTF) exhibited extraordinary catalytic performance and reusability in C-H functionalization by constructing an electronic donor-acceptor system, achieving the highest yield in the photocatalytic C3-H hydroxylation of 2-phenylimidazole[1,2-α]pyridine. This strategy provides a new scaffold for the rational design of CTFs as efficient photocatalysts for organic synthesis.

Photocatalyzed C3-H Nitrosylation of Imidazo[1,2-a]pyridine under Continuous Flow and External Photocatalyst-, Oxidant-, and Additive-Free Conditions.

This study reports a protocol for the highly regioselective photocatalyzed C-H nitrosylation of imidazo[1,2-a]pyridine scaffolds at the C3 position under a combination of visible-light irradiation and continuous flow without any external photocatalyst. This protocol involves mild and safe conditions and shows good tolerance to air and water along with excellent functional group compatibility and site selectivity, generating various 3-nitrosoimidazo[1,2-a]pyridines in excellent yields under photocatalyst-, oxidant-, and additive-free conditions.Notably, the proposed nitrosylation reaction, which introduces the chromophore NO into imidazo[1,2-a]pyridine scaffolds, occurs efficiently under visible-light irradiation without any additional photocatalyst owing to the intense light-absorption characteristics of the nitrosylation products. This study could guide future studies on the development of green organic-synthesis strategies with a wide variety of potential applications.

An analysis of the potential association between obstructive sleep apnea and osteoporosis from the perspective of transcriptomics and NHANES.

BACKGROUND: Obstructive sleep apnea (OSA) and osteoporosis (OP) are prevalent diseases in the elderly. This study aims to reveal the clinical association between OSA and OP and explore potential crosstalk gene targets. METHODS: Participants diagnosed with OSA in the National Health and Nutrition Examination Survey (NHANES) database (2015-2020) were included, and OP was diagnosed based on bone mineral density (BMD). We explored the association between OSA and OP, and utilized multivariate logistic regression analysis and machine learning algorithms to explore the risk factors for OP in OSA patients. Overlapping genes of comorbidity were explored using differential expression analysis, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, Least Absolute Shrinkage and Selection Operator (LASSO) regression, and Random Forest (RF) methods. RESULTS: In the OSA population, the weighted prevalence of OP was 7.0%. The OP group had more females, lower body mass index (BMI), and more low/middle-income individuals compared to the non-OP group. Female gender and lower BMI were identified as independent risk factors for OP in OSA patients. Gene expression profiling revealed 8 overlapping differentially expressed genes in OP and OSA patients. KCNJ1, NPR3 and WT1-AS were identified as shared diagnostic biomarkers or OSA and OP, all of which are associated with immune cell infiltration. CONCLUSION: This study pinpointed female gender and lower BMI as OP risk factors in OSA patients, and uncovered three pivotal genes linked to OSA and OP comorbidity, offering fresh perspectives and research targets.

Rare Earth Evoked Subsurface Oxygen Species in Platinum Alloy Catalysts Enable Durable Fuel Cells.

Alleviating the degradation issue of Pt based alloy catalysts, thereby simultaneously achieving high mass activity and high durability in proton exchange membrane fuel cells (PEMFCs), is highly challenging. Herein, we provide a new paradigm to address this issue via delaying the place exchange between adsorbed oxygen species and surface Pt atoms, thereby inhibiting Pt dissolution, through introducing rare earth bonded subsurface oxygen atoms. We have succeeded in introducing Gd-O dipoles into Pt3 Ni via a high temperature entropy-driven process, with direct spectral evidence attained from both soft and hard X-ray absorption spectroscopies. The higher rated power of 0.93 W cm-2 and superior current density of 562.2 mA cm-2 at 0.8 V than DOE target for heavy-duty vehicles in H2 -air mode suggest the great potential of Gd-O-Pt3 Ni towards practical application in heavy-duty transportation. Moreover, the mass activity retention (1.04 A mgPt -1 ) after 40 k cycles accelerated durability tests is even 2.4 times of the initial mass activity goal for DOE 2025 (0.44 A mgPt -1 ), due to the weakened Pt-Oads bond interaction and the delayed place exchange process, via repulsive forces between surface O atoms and those in the sublayer. This work addresses the critical roadblocks to the widespread adoption of PEMFCs.

Comprehensive analysis of mitochondrial dysfunction and necroptosis in intracranial aneurysms from the perspective of predictive, preventative, and personalized medicine.

Mitochondrial dysfunction and necroptosis are closely associated, and play vital roles in the medical strategy of multiple cardiovascular diseases. However, their implications in intracranial aneurysms (IAs) remain unclear. In this study, we aimed to explore whether mitochondrial dysfunction and necroptosis could be identified as valuable starting points for predictive, preventive, and personalized medicine for IAs. The transcriptional profiles of 75 IAs and 37 control samples were collected from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs), weighted gene co-expression network analysis, and least absolute shrinkage and selection operator (LASSO) regression were used to screen key genes. The ssGSEA algorithm was performed to establish phenotype scores. The correlation between mitochondrial dysfunction and necroptosis was evaluated using functional enrichment crossover, phenotype score correlation, immune infiltration, and interaction network construction. The IA diagnostic values of key genes were identified using machine learning. Finally, we performed the single-cell sequencing (scRNA-seq) analysis to explore mitochondrial dysfunction and necroptosis at the cellular level. In total, 42 IA-mitochondrial DEGs and 15 IA-necroptosis DEGs were identified. Screening revealed seven  key genes invovled in mitochondrial dysfunction (KMO, HADH, BAX, AADAT, SDSL, PYCR1, and MAOA) and five genes involved in necroptosis (IL1B, CAMK2G, STAT1, NLRP3, and BAX). Machine learning confirmed the high diagnostic value of these key genes for IA. The IA samples showed  higher expression of mitochondrial dysfunction and necroptosis. Mitochondrial dysfunction and necroptosis exhibited a close association. Furthermore, scRNA-seq indicated that mitochondrial dysfunction and necroptosis were preferentially up-regulated in monocytes/macrophages and vascular smooth muscle cells (VSMCs) within IA lesions. In conclusion, mitochondria-induced necroptosis was involved in IA formation, and was mainly up-regulated in monocytes/macrophages and VSMCs within IA lesions. Mitochondria-induced necroptosis may be a novel potential target for diagnosis, prevention, and treatment of IA.

Anti-CD79b/CD3 bispecific antibody combined with CAR19-T cells for B-cell lymphoma treatment.

CD19 CAR-T (chimeric antigen receptor-T) cell immunotherapy achieves a remission rate of approximately 70% in recurrent and refractory lymphoma treatment. However, the loss or reduction of CD19 antigen on the surface of lymphoma cells results in the escape of tumor cells from the immune killing of CD19 CAR-T cells (CAR19-T). Therefore, novel therapeutic strategies are urgently required. In this study, an anti-CD79b/CD3 bispecific antibody (BV28-OKT3) was constructed and combined with CAR19-T cells for B-cell lymphoma treatment. When the CD19 antigen was lost or reduced, BV28-OKT3 redirected CAR19-T cells to CD79b+ CD19- lymphoma cells; therefore, BV28-OKT3 overcomes the escape of CD79b+ CD19- lymphoma cells by the killing action of CAR19-T cells in vitro and in vivo. Furthermore, BV28-OKT3 triggered the antitumor function of CAR- T cells in the infusion product and boosted the antitumor immune response of bystander T cells, markedly improving the cytotoxicity of CAR19-T cells to lymphoma cells in vitro and in vivo. In addition, BV28-OKT3 elicited the cytotoxicity of donor-derived T cells toward lymphoma cells in vitro, which depended on the presence of tumor cells. Therefore, our findings provide a new clinical treatment strategy for recurrent and refractory B-cell lymphoma by combining CD79b/CD3 BsAb with CAR19-T cells.

Temperature Effects on Electrochemical Energy-Storage Materials: A Case Study of Yttrium Niobate Porous Microspheres.

Lithium-ion batteries (LIBs) are very popular electrochemical energy-storage devices. However, their applications in extreme environments are hindered because their low- and high-temperature electrochemical performance is currently unsatisfactory. In order to build all-climate LIBs, it is highly desirable to fully understand the underlying temperature effects on electrode materials. Here, based on a novel porous-microspherical yttrium niobate (Y0.5 Nb24.5 O62 ) model material, this work demonstrates that the operation temperature plays vital roles in electrolyte decomposition on electrode-material surfaces, electrochemical kinetics, and crystal-structure evolution. When the operation temperature increases, the reaction between the electrolyte and the electrode material become more intensive, causing the formation of thicker solid electrolyte interface (SEI) films, which decreases the initial Coulombic efficiency. Meanwhile, the electrochemical kinetics becomes faster, leading to the larger reversible capacity, higher rate capability, and more suitable working potential (i.e., lower working potential for anodes and higher working potential for cathodes). Additionally, the maximum unit-cell-volume change becomes larger, resulting in poorer cyclic stability. The insight gains here can provide a universal guide for the exploration of all-climate electrode materials and their modification methods.

Sex-based differences in the outcomes of intracerebral haemorrhage: A systematic review and meta-analysis.

INTRODUCTION: To provide updated evidence on the sex-based differences in the risk of mortality and functional outcomes in subjects with intracerebral haemorrhage. METHODS: A systematic search of eligible studies was conducted using three large databases such as PubMed, EMBASE, and Scopus for observational studies that documented the comparative risk of mortality and functional outcomes based on the subjects' sex. Only studies published in the year 2000 and onwards were included. Random effects model was used to pool relevant data and effect sizes were reported as odds ratio (OR) with 95% confidence intervals (CI). RESULTS: The review included 32 studies. In most of the studies, female subjects had a higher mean age compared to males and had a higher rate of neurological deficits at admission. A higher proportion of males had cardiovascular risk factors. The risk of mortality at hospital discharge (OR 0.98, 95% CI: 0.90, 1.06), and one- (OR 0.98, 95% CI: 0.81, 1.18), three- (OR 1.13, 95% CI: 0.95, 1.33) and 12-months (OR 1.04, 95% CI: 0.90, 1.19) follow up was similar in both sexes. Compared to females, males had a lower risk of poor functional outcomes at 3 months (OR 0.83, 95% CI: 0.77, 0.89) and 12 months (OR 0.87, 95% CI: 0.77, 0.98) follow-up. CONCLUSION: There is a similar risk of mortality but better functional outcomes in males with intracerebral haemorrhage compared to females. However, the findings should be interpreted cautiously as there were significant sex-based differences in risk profiles at admission. Further studies that focus on careful and meticulous examination of sex-specific association with survival and functional outcomes are needed.

A novel aptamer beacon for rapid screening of recombinant cells and in vivo monitoring of recombinant proteins.

Recombinant protein drugs, which are typically produced by mammalian host cells, have been approved for the treatment of a range of diseases. Accordingly, systems for selecting recombinant cell lines with efficient protein expression and for testing the content of recombinant proteins in vivo are crucial to the large-scale production and application of protein-based therapeutic drugs. In this study, we designed three aptamer beacons to detect His-tag, a common label of recombinant proteins. We found that all three beacons could specifically and quantitatively measure the His-tagged recombinant proteins with a short reaction time. Among these three beacons, the 6H5-MU beacon had the highest sensitivity for His polypeptides with a detection limit of 250 ng/mL and the shortest detection time within 1 min. Furthermore, we established a rapid and highly effective recombinant cell line construction system, which could obtain monoclonal cell lines with high yields of target proteins within 21 days, by combining 6H5-MU with pSB, a novel plasmid composed of a Sleeping Beauty transposase and a transposon. Finally, 6H5-MU also discriminately tested the serum concentration of His-tagged recombinant proteins in vivo, with consistent results compared to enzyme-linked immunosorbent assay (ELISA). We thus established a rapid and high-throughput method for generating recombinant cell lines and in vivo monitoring of recombinant protein levels, thereby providing a new platform for the development and preparation of recombinant protein drugs. KEY POINTS: • The 6H5-MU aptamer beacon rapidly and accurately binds to His-tagged recombinant proteins. • A system for rapid and high-throughput generation of recombinant cell lines is established using 6H5-MU and pSB. • 6H5-MU allows in vivo monitoring of recombinant protein levels.

Modulating the Oxygen Reduction Reaction Performance via Precisely Tuned Reactive Sites in Porphyrin-Based Covalent Organic Frameworks.

Covalent organic frameworks (COFs) have emerged as promising electrocatalysts due to their controllable architectures, highly exposed molecular active sites, and ordered structures. In this study, a series of porphyrin-based COFs (TAPP-x-COF) with various transition metals (Co, Ni, Fe) were synthesized via a facile post-metallization strategy under solvothermal synthesis. The resulting porphyrin-based COFs showed oxygen reduction reaction (ORR) activity with a trend in Co > Fe > Ni. Among them, TAPP-Co-COF exhibited the best ORR activity (E1/2 = 0.66 V and jL = 4.82 mA cm-2) in alkaline media, which is comparable to those of Pt/C under the same conditions. Furthermore, TAPP-Co-COF was employed as a cathode in a Zn-air battery, demonstrating a high power density of 103.73 mW cm-2 and robust cycling stability. This work presents a simple method for using COFs as a smart platform to fabricate efficient electrocatalysts.

Associations of the audited residential neighborhood built-environment attributes with objectively-measured sedentary time among adults: a systematic review.

This study systematically reviewed the relevant studies and summarized the associations of objective measures of residential neighborhood built-environment attributes with sedentary time among adults. Published studies were obtained from PubMed and Scopus, restricting to those published in English language peer-reviewed journals to Oct. 2021. There were nine studies and 48 instances of estimated associations. Most instances showed no statistical-significant associations; by contrast, few instances showed that adults living in a neighborhood characterized by a high density of local destinations and connected intersections were associated with less sedentary time. The findings suggest that a high density of destinations and street intersections around residence may provide opportunities to transfer and access to services, thus reducing the sedentary time. Future research strengthening the research design and measurements are needed to investigate the potential explanations of the associations between residential neighborhood built environments and sedentary time in adults.

Long non-coding RNAs are involved in alternative splicing and promote cancer progression.

Alternative splicing (AS) is a key process in which precursor RNAs produce different mature RNAs, and the disorder of AS is a key factor in promoting cancer development. Compared with coding RNA, studies on the functions of long non-coding RNAs (lncRNAs) are far from enough. In fact, lncRNA is an important participant and regulator in the process of AS. On the one hand, lncRNAs regulate cancer progression as AS products of precursor messenger RNA (mRNA), but on the other hand, precursor lncRNA generates cancer-related abnormal splicing variants through AS. In addition, lncRNAs directly or indirectly regulate the AS events of downstream target genes, thus affecting the occurrence and development of cancer. Here, we reviewed how lncRNAs regulate AS and influence oncogenesis in different ways.

Design of Photoactive Covalent Organic Frameworks as Heterogeneous Catalyst for Preparation of Thiophosphinates from Phosphine Oxides and Thiols.

Two new covalent organic frameworks (COFs) were synthesized from 4,4',4'',4'''-(pyrene-1,3,6,8-tetrayl)tetraaniline and 2,5-dimethoxyterephthalaldehyde (Py-DMTA-COF) or 2',5'-dimethoxy-[1,1':4',1''-terphenyl]-4,4''-dicarbaldehyde (Py-DMTPDA-COF) under solvothermal conditions. These two COFs were further facilely developed as efficient photocatalytic platforms for the synthesis of thiophosphinates. Py-DMTA-COF exhibited better photocatalytic activity, broad substrate applicability, and excellent recycling capacity for the preparation of thiophosphinates from P(O)H compounds and thiols compared to Py-DMTPDA-COF. This methodology was further extended to the seamless gram-scale production of target phosphorothioate derivatives. The results demonstrate that COFs can provide a robust platform for developing metal-free, base-free, highly efficient, and reusable heterogeneous photocatalysts for organic transformations.

The Influence of NDRG1 Single Nucleotide Polymorphisms on Glioma Risk and Prognosis in Chinese Han Population.

Glioma is a highly fatal malignant tumor with a high recurrence rate, poor clinical treatment effect, and prognosis. We aimed to determine the association between single nucleotide polymorphisms (SNPs) of NDRG1 and glioma risk and prognosis in the Chinese Han population. 5 candidate SNPs were genotyped by Agena MassARRAY in 558 cases and 503 controls; logistic regression was used to analyze the relationship between SNPs and glioma risk. We used multi-factor dimensionality reduction to analyze the interaction of 'SNP-SNP'; the prognosis analysis was performed by log-rank test, Kaplan-Meier analysis, and Cox regression model. Our results showed that the polymorphisms of rs3808599 was associated with the reduction of glioma risk in all participants (OR 0.41, p = 0.024) and the participants ≤ 40 years old (OR 0.30, p = 0.020). rs3802251 may reduce glioma risk in all participants (OR 0.79, p = 0.008), the male participants (OR 0.68, p = 0.033), and astrocytoma patients (OR 0.81, p = 0.023). rs3779941 was associated with poor glioma prognosis in all participants (HR = 2.59, p = 0.039) or astrocytoma patients (HR = 2.63, p = 0.038). We also found that the key factors for glioma prognosis may include surgical operation, radiotherapy, and chemotherapy. This study is the first to find that NDRG1 gene polymorphisms may have a certain association with glioma risk or prognosis in the Chinese Han population.

In Situ Construction of Co-MoS2/Pd Nanosheets on Polypyrrole-Derived Nitrogen-Doped Carbon Microtubes as Multifunctional Catalysts with Enhanced Catalytic Performance.

The structural design of multiple functional components could integrate synergistic effects to enhance the catalytic performance of MoS2-based composites for catalytic applications. Herein, one-dimensional (1D) Co-MoS2/Pd@NCMTs composites were designed to prepare Co-doped MoS2/Pd nanosheets (NSs) on N-doped carbon microtubes (NCMTs) from tubular polypyrrole (PPy) as multifunctional catalysts. The Co-MoS2/Pd@NCMTs composites integrated the synergistic effects of Co-doping, a 1D tubular structure, and noble-metal Pd decoration. Thus, a higher catalytic activity was observed in 4-nitrophenol (4-NP) reduction and peroxidase-like catalysis than other components, such as MoS2, MoS2@NCMTs, and Co-MoS2@NCMTs. Remarkably, the results indicated that the dissolution, diffusion, and redistribution led to the dissolution of MoO3@ZIF-67 cores and generation of Co-doped MoS2 NSs. Benefiting from the synergistic effect from these components, Co-MoS2/Pd@NCMTs were considered as a facile colorimetric sensing platform for detecting tannic acid. Moreover, outstanding performance was realized in the reduction of 4-NP with the composites. Thus, we provide a simple synthetic strategy for simultaneously integrating electronic engineering and structural advantages to develop an efficient MoS2-based multifunctional catalyst.

Enhanced Acidic Water Oxidation by Dynamic Migration of Oxygen Species at the Ir/Nb2 O5-x Catalyst/Support Interfaces.

Catalyst/support interaction plays a vital role in catalysis towards acidic oxygen evolution (OER), and the performance reinforcement is currently interpreted by either strain or electron donation effect. We herein report that these views are insufficient, where the dynamic evolution of the interface under potential bias must be considered. Taking Nb2 O5-x supported iridium (Ir/Nb2 O5-x ) as a model catalyst, we uncovered the dynamic migration of oxygen species between IrOx and Nb2 O5-x during OER. Direct spectroscopic evidence combined with theoretical computation suggests these migrations not only regulate the in situ Ir structure towards boosted activity, but also suppress its over-oxidation via spontaneously delivering excessive oxygen from IrOx to Nb2 O5-x . The optimized Ir/Nb2 O5-x thus demonstrated exceptional performance in scalable water electrolyzers, i.e., only need 1.839 V to attain 3 A cm-2 (surpassing the DOE 2025 target), and no activity decay during a 2000 h test at 2 A cm-2 .

Ligand-Directed Conformational Control over Porphyrinic Zirconium Metal-Organic Frameworks for Size-Selective Catalysis.

Zirconium-based metal-organic frameworks (Zr-MOFs) have aroused enormous interest owing to their superior stability, flexible structures, and intriguing functions. Precise control over their crystalline structures, including topological structures, porosity, composition, and conformation, constitutes an important challenge to realize the tailor-made functionalization. In this work, we developed a new Zr-MOF (PCN-625) with a csq topological net, which is similar to that of the well-known PCN-222 and NU-1000. However, the significant difference lies in the conformation of porphyrin rings, which are vertical to the pore surfaces rather than in parallel. The resulting PCN-625 exhibits two types of one-dimensional channels with concrete diameters of 2.03 and 0.43 nm. Furthermore, the vertical porphyrins together with shrunken pore sizes could limit the accessibility of substrates to active centers in the framework. On the basis of the structural characteristics, PCN-625(Fe) can be utilized as an efficient heterogeneous catalyst for the size-selective [4 + 2] hetero-Diels-Alder cycloaddition reaction. Due to its high chemical stability, this catalyst can be repeatedly used over six times. This work demonstrates that Zr-MOFs can serve as tailor-made scaffolds with enhanced flexibility for target-oriented functions.