Photoinduced Electron Donor Acceptor Complex-Enabled α-C(sp3)-H Alkenylation of Amines.

Allylic amines are prevalent and vital structural components present in many bioactive compounds and natural products. Additionally, they serve as valuable intermediates and building blocks, with wide-ranging applications in organic synthesis. However, direct α-C(sp3)-H alkenylation of feedstock amines, particularly for the preparation of α-alkenylated cyclic amines, has posed a longstanding challenge. Herein, we present a general, mild, operationally simple, and transition-metal-free α-alkenylation of various readily available amines with alkenylborate esters in excellent E/Z - and diastereoselectivities. This method features good compatibility with water and oxygen, broad substrate scope, and excellent functional group tolerance, thereby enabling the late-stage modification of various complex molecules. Mechanistic studies suggest that the formation of a photoactive electron donor-acceptor complex between 2-iodobenzamide and the tetraalkoxyborate anion, which subsequently undergoes photoinduced single electron transfer and intramolecular 1,5-hydrogen atom transfer to generate the crucial α-amino radicals, is the key to success of this chemistry.

Harnessing Bottom-Up Self-Assembly To Position Five Distinct Components in an Ordered Porous Framework.

Positioning a diverse set of building blocks in a well-defined array enables cooperativity amongst them and the systematic programming of functional properties. The extension of this concept to porous metal-organic frameworks (MOFs) is challenging since the installation of multiple components in a well-ordered framework requires careful design of the lattice topology, judicious selection of building blocks, and precise control of the crystallization parameters. Herein, we report how we met these challenges to prepare the first quinary MOF structure, FDM-8, by bottom-up self-assembly from two metals, ZnII and CuI , and three distinct carboxylate- and pyrazolate-based linkers. With a surface area of 3643 m2 g-1 , FDM-8 contains hierarchical pores and shows outstanding methane-storage capacity at high pressure. Furthermore, functional groups introduced on the linkers became compartmentalized in predetermined arrays in the pores of the FDM-8 framework.

MicroRNA-492 overexpression involves in cell proliferation, migration, and radiotherapy response of cervical squamous cell carcinomas.

MicroRNAs (miRNAs) are small non-coding RNA that target protein-coding mRNAs at the post-transcriptional level. The aim of this study was to define the role of miR-492 in cervical squamous cell carcinomas. After microRNA profiling and comparison, we firstly detected miR-492 expression in 104 tumor tissues biopsies derived from advanced staged (FIGO IIB-IIIB) cervical squamous cell carcinoma patients before receiving concomitant chemoradiotherapy and found miR-492 expression was significantly higher in the specimens that were sensitive to concomitant chemoradiotherapy, as compared with insensitive cancer specimens (P < 0.05). Moreover, higher expression of miR-492 was associated with pelvic lymph node metastasis (LNM) (P < 0.05). Further studies illustrated ectopic miR-492 overexpression in SiHa cells promoted cell proliferation, migration, and enhanced the sensitivity of cervical cancer cells to irradiation by promoting apoptosis. In addition, we identified TIMP2 as a direct miR-492 target, which has been shown to be critical in modulating cancer cell migration and invasion. We also confirmed that miR-492 expression levels in positive pelvic LNM were much higher than negative LNM and miR-492 played a vital role in pelvic lymph node metastasis via regulating miR-492/TIMP2/MMP10 axis. In particular, miR-492 was correlated with prognosis in the subgroup of patients with negative pelvic LNM (P < 0.05) and had a promising value in predicting treatment response in the subgroup of patients with positive pelvic LNM (an AUC of 85%, 75.00% specificity, and 95.24% sensitivity). Taken together, the results suggested that miR-492 may serve as a potential biomarker for cervical cancer treatment and prognosis.

Infertile polycystic ovary syndrome patients undergoing in vitro fertilization with the gonadotropin-releasing hormone-antagonist protocol: role of hyperandrogenism.

This retrospective cohort study is to assess the effects of hyperandrogenism (HA) in polycystic ovary syndrome (PCOS) patients with gonadotropin-releasing hormone (GnRH)-antagonist protocol during in vitro fertilization (IVF). Total 892 infertile Patients between 20 and 35 years of age with normal body mass index (BMI, 18.50 -24.99 kg/m2), including those with tubal factor infertility (control, n = 318), PCOS infertility with HA (HA PCOS, n = 244), and PCOS infertility without HA (non-HA PCOS, n = 330), were included. Number of retrieved oocytes was significantly higher and total Gonadotropin consumption was significant lower in the HA PCOS group, whereas abortion rate was significantly higher and live birth rate was significantly lower in the HA PCOS group, compared with the control and non-HA PCOS groups. In the HA PCOS group, the number of available embryos tended to be higher with no significance. The GnRH-antagonist protocol is more suitable for HA PCOS patients, with lower cost and more number of embryos available for transfer. Due to the high abortion rate and low live birth rate, a freeze-all approach might be a preferable option for HA PCOS patients so as to create a buffer for reducing androgen levels before transferring freeze-thawed embryos.

Reversible Redox Activity in Multicomponent Metal-Organic Frameworks Constructed from Trinuclear Copper Pyrazolate Building Blocks.

Inorganic functionalization of metal-organic frameworks (MOFs), such as incorporation of multiple inorganic building blocks with distinct metals into one structure and further modulation of the metal charges, endows the porous materials with significant properties toward their applications in catalysis. In this work, by an exploration of the role of 4-pyrazolecarboxylic acid (H2PyC) in the formation of trinuclear copper pyrazolate as a metalloligand in situ, four new MOFs with multiple components in order were constructed through one-pot synthesis. This metalloligand strategy provides multicomponent MOFs with new topologies (tub for FDM-4 and tap for FDM-5) and is also compatible with a second organic linker for cooperative construction of complex MOFs (1,4-benzenedicarboxylic acid for FDM-6 and 2,6-naphthalenedicarboxylic acid for FDM-7). The component multiplicity of these MOFs originates from PyC's ability to separate Cu and Zn on the basis of their differentiated binding affinities toward pyrazolate and carboxylate. These MOFs feature reversible and facile redox transformations between CuI3(PyC)3 and CuII3(µ-OH)(PyC)3(OH)3 without altering the connecting geometries of the units, thus further contributing to the significant catalytic activities in the oxidation of CO and aromatic alcohols and the decomposition of H2O2. This study on programming multiple inorganic components into one framework and modulating their electronic structures is an example of functionalizing the inorganic units of MOFs with a high degree of control.

Heterogeneity within a Mesoporous Metal-Organic Framework with Three Distinct Metal-Containing Building Units.

Materials built from multiple constituents have revealed emerging properties that are beyond linear integration of those from single components. We report a mesoporous metal-organic framework made from three geometrically distinct metal-containing secondary building units (SBUs) as a result of topological induction. The combinations of the Cu-based triangular, Zn-based octahedral, and Zn-based square pyramidal SBUs have created four types of cages in the network, despite that only one organic linker pyrazolecarboxylate was used. The longest distance for molecules maneuvering inside the largest cage is 5.2 nm. Furthermore, the complex and diversified pore environments allow the installation of various new functionalities in the framework as well as the expedited Ag nanoparticle formation in the pores. As presented in the molecule movement diagram, the crystal has provided specific arrangements of cages and apertures with distinct chemical features for guests transporting between the pores.

Distinct Packings of Supramolecular Building Blocks in Metal-Organic Frameworks Based on Imidazoledicarboxylic Acid.

When the supramolecular building block packings (face-centered, body-centered, and primitive cubic) with different interactions (hydrogen and coordination bonding) were controlled, four new structures based on octahedral M(II) (M = Zn, Ni, Mn) and imidazoledicarboxylate were constructed. The interaction modes between the supramolecular building blocks affect the water stability of the structures. Furthermore, with uncoordinated carboxylate O atoms in the structures, these compounds demonstrate a strong capability of capturing metal ions in the solution.

Ordered vacancies and their chemistry in metal-organic frameworks.

Vacancies are common in solid materials, but it remains a challenge to introduce them at specific locations with controlled distributions. Here we report the creation of ordered metal vacancies and linker vacancies in a cubic metal-organic framework (MOF) based on Zn(II) and pyrazolecarboxylic acid by removing a quarter of the metal ions and half of the linkers. The MOF with ordered vacancies shows increased pore size, thus allowing large dye molecules to fit in the pores. Furthermore, by filling the vacancies with new metals and new linkers, eight new single-crystalline MOFs with multicomponents in absolute order are introduced. The capability of performing stepwise elimination and addition reactions systematically in extended solids without destroying the structural integrity has generated complex MOF structures which otherwise cannot be made.

Co-administration of GnRH-agonist and hCG (double trigger) for final oocyte maturation increases the number of top-quality embryos in patients undergoing IVF/ICSI cycles.

BACKGROUND: The utilization of a double trigger, involving the co-administration of gonadotropin-releasing hormone agonist (GnRH-a) and human chorionic gonadotropin (hCG) for final oocyte maturation, is emerging as a novel approach in gonadotropin-releasing hormone antagonist (GnRH-ant) protocols during controlled ovarian hyperstimulation (COH). This protocol involves administering GnRH-a and hCG 40 and 34 h prior to ovum pick-up (OPU), respectively. This treatment modality has been implemented in patients with low/poor oocytes yield. This study aimed to determine whether the double trigger could improve the number of top-quality embryos (TQEs) in patients with fewer than three TQEs. METHODS: The stimulation characteristics of 35 in vitro fertilization (IVF) cycles were analyzed. These cycles were triggered by the combination of hCG and GnRHa (double trigger cycles) and compared to the same patients' previous IVF attempt, which utilized the hCG trigger (hCG trigger control cycles). The analysis involved cases who were admitted to our reproductive center between January 2018 and December 2022. In the hCG trigger control cycles, all 35 patients had fewer than three TQEs. RESULTS: Patients who received the double trigger cycles yielded a significantly higher number of 2PN cleavage embryos (3.54 ± 3.37 vs. 2.11 ± 2.15, P = 0.025), TQEs ( 2.23 ± 2.05 vs. 0.89 ± 0.99, P < 0.001), and a simultaneously higher proportion of the number of cleavage stage embryos (53.87% ± 31.38% vs. 39.80% ± 29.60%, P = 0.043), 2PN cleavage stage embryos (43.89% ± 33.01% vs. 27.22% ± 27.13%, P = 0.014), and TQEs (27.05% ± 26.26% vs. 14.19% ± 19.76%, P = 0.019) to the number of oocytes retrieved compared with the hCG trigger control cycles, respectively. The double trigger cycles achieved higher rates of cumulative clinical pregnancy (20.00% vs. 2.86%, P = 0.031), cumulative persistent pregnancy (14.29% vs. 0%, P < 0.001), and cumulative live birth (14.29% vs. 0%, P < 0.001) per stimulation cycle compared with the hCG trigger control cycles. CONCLUSION: Co-administration of GnRH-agonist and hCG for final oocyte maturation, 40 and 34 h prior to OPU, respectively (double trigger) may be suggested as a valuable new regimen for treating patients with low TQE yield in previous hCG trigger IVF/intracytoplasmic sperm injection (ICSI) cycles.

A hybrid algorithm of grey wolf optimizer and harris hawks optimization for solving global optimization problems with improved convergence performance.

The grey wolf optimizer is an effective and well-known meta-heuristic algorithm, but it also has the weaknesses of insufficient population diversity, falling into local optimal solutions easily, and unsatisfactory convergence speed. Therefore, we propose a hybrid grey wolf optimizer (HGWO), based mainly on the exploitation phase of the harris hawk optimization. It also includes population initialization with Latin hypercube sampling, a nonlinear convergence factor with local perturbations, some extended exploration strategies. In HGWO, the grey wolves can have harris hawks-like flight capabilities during position updates, which greatly expands the search range and improves global searchability. By incorporating a greedy algorithm, grey wolves will relocate only if the new location is superior to the current one. This paper assesses the performance of the hybrid grey wolf optimizer (HGWO) by comparing it with other heuristic algorithms and enhanced schemes of the grey wolf optimizer. The evaluation is conducted using 23 classical benchmark test functions and CEC2020. The experimental results reveal that the HGWO algorithm performs well in terms of its global exploration ability, local exploitation ability, convergence speed, and convergence accuracy. Additionally, the enhanced algorithm demonstrates considerable advantages in solving engineering problems, thus substantiating its effectiveness and applicability.

Buried-Interface Engineering of Conformal 2D/3D Perovskite Heterojunction for Efficient Perovskite/Silicon Tandem Solar Cells on Industrially Textured Silicon.

Exploring strategies to control the crystallization and modulate interfacial properties for high-quality perovskite film on industry-relevant textured crystalline silicon solar cells is highly valued in the perovskite/silicon tandem photovoltaics community. The formation of a 2D/3D perovskite heterojunction is widely employed to passivate defects and suppress ion migration in the film surface of perovskite solar cells. However, realizing solution-processed heterostructures at the buried interface faces solvent incompatibilities with the challenge of underlying-layer disruption, and texture incompatibilities with the challenge of uneven coverage. Here, a hybrid two-step deposition method is used to prepare robust 2D perovskites with cross-linkable ligands underneath the 3D perovskite. This structurally coherent interlayer benefits by way of preferred crystal growth of strain-free and uniform upper perovskite, inhibits interfacial defect-induced instability and recombination, and promotes charge-carrier extraction with ideal energy-level alignment. The broad applicability of the bottom-contact heterostructure for different textured substrates with conformal coverage and various precursor solutions with intact properties free of erosion are demonstrated. With this buried interface engineering strategy, the resulting perovskite/silicon tandem cells, based on industrially textured Czochralski (CZ) silicon, achieve a certified efficiency of 28.4% (1.0 cm2 ), while retaining 89% of the initial PCE after over 1000 h operation.

Metabolic profiles characterizing different phenotypes of polycystic ovary syndrome: plasma metabolomics analysis.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder accompanied with an increased risk of developing type 2 diabetes mellitus and cardiovascular disease; despite being a common condition, the pathogenesis of PCOS remains unclear. Our aim was to investigate the potential metabolic profiles for different phenotypes of PCOS, as well as for the early prognosis of complications. METHODS: A total of 217 women with PCOS and 48 healthy women as normal controls were studied. Plasma samples of subjects were tested using two different analytical platforms of metabolomics: 1H nuclear magnetic resonance (NMR) and gas chromatography/time-of-flight mass spectrometry (GC/TOF-MS). RESULTS: Our results showed that carbohydrate, lipid and amino acid metabolisms were influenced in PCOS. The levels of lactate, long-chain fatty acids, triglyceride and very low-density lipoprotein were elevated, while glucose, phosphatidylcholine and high-density lipoprotein (HDL) concentrations were reduced in PCOS patients as compared with controls. Additionally, the levels of alanine, valine, serine, threonine, ornithine, phenylalanine, tyrosine and tryptophan were generally increased, whereas the levels of glycine and proline were significantly reduced in PCOS samples compared to controls. Furthermore, the ratio of branched-chain amino acid to aromatic amino acid concentrations (BCAA/AAA) in PCOS plasma was significantly reduced in PCOS patients and was insusceptible to obesity and insulin sensitivity. CONCLUSIONS: Our results suggested that the enhanced glycolysis and inhibited tricarboxylic acid cycle (TAC) in women with PCOS. Decrease of BCAA/AAA ratio was directly correlated with the development of PCOS. Ovulatory dysfunction of PCOS patients was associated with raised production of serine, threonine, phenylalanine, tyrosine and ornithine. Elevated levels of valine and leucine, and decreased concentrations of glycine in PCOS plasma could contribute to insulin sensitivity and could be considered as the potential biomarkers for long-term risk assessment of diabetes mellitus.

Association of TRB3 Q84R polymorphism with polycystic ovary syndrome in Chinese women.

BACKGROUND: Tribbles 3 (TRB3) affects insulin signalling by inhibiting insulin-stimulated Akt phosphorylation and subsequent activation. A single nucleotide polymorphism located in the second extron of the human TRB3 gene is thought to be associated with insulin resistance. The latter is a core abnormality in PCOS independent of obesity. The present study was designed to clarify the relationships of TRB3 Q84R polymorphism with PCOS in a Chinese women group. METHODS: A case-control study with two groups: PCOS group (n = 336) and control group of infertility women for tubal and/or male factor (n = 116) was performed. Genotyping of the TRB3 R84 variant was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: The frequency of genotype QQ in PCOS women was significantly lower, while genotype QR and RR were significantly higher than that in control group (p < 0.05). However, the difference disappeared after adjustment for BMI. At glucose1h, glucose2h and insulin2h point, the difference between QQ individuals and R84 allele carriers in PCOS women reached statistical significance during OGTT (p < 0.05). CONCLUSIONS: TRB3 Q84R polymorphism is associated with obesity and especially glucose metabolism and not associated with polycystic ovary syndrome because of compositional characteristics of phenotype in Chinese PCOS women.

ER-α36, a novel variant of estrogen receptor α, is involved in EGFR-related carcinogenesis in endometrial cancer.

OBJECTIVE: To explore the role of estrogen receptor-α36 (ER-α36) in epidermal growth factor receptor (EGFR)-related carcinogenesis in endometrial cancer. STUDY DESIGN: The expression of ER-α36, EGFR, and phospho-extracellular signal-regulated kinase was analyzed using immunohistochemistry in endometrial cancer samples. The cellular localization of ER-α36 and EGFR was determined using immunofluorescence in the endometrial cancer Hec1A cells. The level of phospho-extracellular signal-regulated kinase of Hec1A cells was determined using Western blotting after treatment with epidermal growth factor. RESULTS: Positive rate of ER-α36 was increased in high-stage (P = .03) and high-grade (P = .224) endometrial cancer; expression of ER-α36 and EGFR exhibited a significant positive correlation (r = 0.334, P = .025) and they showed substantial colocalization on the plasma membrane of glandular cells; phospho-extracellular signal-regulated kinase positive rate in ER-α36 positive group and EGFR positive group was higher than that of ER-α36 negative group (P = .014) and EGFR negative group (P = .016); finally, ER-α36 mediated epidermal growth factor-stimulated extracellular signal-regulated kinase activation in Hec1A cells. CONCLUSION: ER-α36 mediates EGFR-related extracellular signal-regulated kinase activation in endometrial cancer.

[Application of self-propelled micro-/nanomotors in active targeted drug delivery].

As a new type of micro-/nanomachines, self-propelled micro-/nanomotors (MNMs) can convert chemical or external energies from the surrounding environment into mechanical forces to produce autonomous motion. The ability of autonomous movement allows these MNMs to move actively to the targeted locations, and thus confers great potentials on the MNMs for applications in biomedicine, especially in drug delivery. MNMs have been shown to effectively load therapeutic payloads for active delivery to the disease site, which greatly improves the therapeutic efficacy and reduces side effects compared with the traditional nanodrugs. In this review, we provide an overview of different propulsion mechanisms of MNMs, including chemical propulsion based on redox reaction and external field propulsion driven by external energy such as light, magnetic field, electric field and ultrasound, followed by a review of the recent progress in active drug delivery based on MNMs in the past decade. We also discuss the current challenges and future perspectives of the application of the MNMs.

New linker installation in metal-organic frameworks.

In this Frontier article, we provide a brief overview of recent progress in the new organic component installation in metal-organic frameworks (MOFs) by single-crystal to single-crystal transformation. We discuss the criteria for the MOFs which could provide accessible vacant sites for new linker installation. We highlight three different categories of linker installation based on the nature and the roles of the new linkers. The present challenges and future opportunities in this field are also discussed.

Application of accelerometer-based gait recognition to adjuvant clinical gait analysis.

BACKGROUND: Gait recognition is an emerging biometric technology applied to the mobile environment. With built-in accelerometers, wearable devices are used to recognize user identity according to gait periodic pattern, which shows strong stability and uniqueness property. OBJECTIVE: The purpose of this study is to build analyzing models to find the change of gait normal and pathological function based on gait features. METHODS: This work relies on gait recognition methods. In this paper, the performance of different hybrid filter methods is compared by combining four classical filtering methods. The influence of the abnormal pattern of gait cycle is estimated by standard deviation. The effectiveness of feature matching methods is evaluated by six classical distance discrimination function. RESULTS: The results highlight the stability and invariance of gait periodic pattern. For analyzing models, the best recognition rate is 96.67% with the combination of MF hybrid filter and Correlation distance function in the small sample, and minimal time consumption is 0.038 s. The effectiveness of analyzing models is further analyzed for different practical applications. CONCLUSIONS: This study provides evidence for future scientific teams to make decisions on selecting filter methods and discrimination functions which can more efficiently extract gait features and suggest ways to analyze clinical gait pattern.

Photochemical cycloaddition and temperature-dependent breathing in pillared-layer metal-organic frameworks.

Single crystallinity of metal-organic frameworks (MOFs) enables the studies of their flexible behaviors with atomic precision. Here, we investigated the structural transformations triggered by photochemical cycloaddition and with temperature-dependent breathing in a series of pillared-layer MOF structures using a variety of pyrazolecarboxylate linkers for the layers and bipyridyl linkers as the pillars. The ethylenic double bonds from the pillars in close proximity undergo quantitative and seteroselective photochemical [2 + 2] cycloaddition upon UV irradiation, transforming the MOFs into structures with cyclobutane-based pillars. Furthermore, reversible breathing of the new pillared-layer MOF was evidenced by the 10.8% unit cell parameter change along c axis upon temperature change between 298 and 173 K. As revealed by single crystal X-ray diffraction, this transformation originates from the relative flattening of the wavy layers upon cooling. These two different types of characteristic structural transformations responding to inherent reactions and external stimuli happen at single crystalline state, providing a well-defined robust system with controlled flexibility.

Interface construction in microporous metal-organic frameworks from luminescent terbium-based building blocks.

Interfaces between the pores and the skeletons in metal-organic frameworks (MOFs) define the places where the materials interact with the incoming guests, and constructing functionalized interfaces in MOFs is crucial for various applications. In this report, by using the platform of the well-known terbium-based 12-connected building units, four isoreticular MOFs, FDM-34-37, with fcu-a topology in single crystal form were obtained with linear organic linkers featuring diversified edge lengths (from 17.4 to 23.8 Å) and functionalities (naphthalene, bipyridine, stilbene, and rotatable triphenyl rings). With the surface areas of up to 1850 m2 g-1, these MOFs feature distinct pores with fine-tuned sizes. Furthermore, the relationship between the luminescence originated from the terbium, and the energy transfer between the metals and the linkers on the interfaces were carefully investigated. With characteristic luminescence and potentially active sites from both the metals and the linkers, these MOFs show prospects in various applications.

Enhanced performance in gas adsorption and Li ion batteries by docking Li(+) in a crown ether-based metal-organic framework.

Incorporating supramolecular interaction units, crown ether rings, into metal-organic frameworks enables the docking of metal ions through complexation for enhanced performance in H2 and CO2 adsorption and lithium ion batteries.