Single-molecule magnet behavior in heterometallic decanuclear [Ln2Fe8] (Ln = Y, Dy, Ho, Tb, Gd) coordination clusters.

Five decanuclear lanthanide-iron clusters, formulated as [Ln2Fe8(hmp)10(µ2-OH)4(µ3-OH)2(µ4-O)4(H2O)6]·6ClO4·xH2O (x ≈ 8, Ln = Y for 1; x ≈ 6, Ln = Dy for 2; x ≈ 6, Ln = Ho for 3; x ≈ 7, Ln = Tb for 4; x ≈ 7, Ln = Gd for 5, Hhmp = 2-(hydroxymethyl)pyridine), have been synthesized and structurally characterized. Single-crystal structural analysis reveals that the cluster consists of six face-sharing defective cubane units. Dynamic magnetic investigations indicated that cluster 2 exhibits single-molecule magnet behavior under a zero dc field eliciting an effective energy barrier of Ueff = 17.76 K and a pre-exponential factor of τ0 = 7.93 × 10-8 s. Investigation of the performance of a series of FeIII-DyIII SMMs indicates that the relatively low energy barrier in 2 is associated with the weak ferromagnetic coupling between FeIII and DyIII ions, while the strength of ferromagnetic interaction in these clusters is mainly related to the bond distances between DyIII and O atoms coordinated to FeIII ions. Clusters 3 and 4 exhibit similar dual relaxation pathways under their respective optimal external applied dc field, where the direct relaxation process occurs in the low-frequency area, which impedes the extraction of the Ueff, while the secondary relaxation process appears at a higher frequency, which is probably a connection with intermolecularly driven relaxation. Our findings offer a magneto-structural correlation model for further investigating the single-molecule magnet behavior in lanthanide-iron systems.

Comparison of errors in ablation depth calculation after myopic femtosecond laser in situ keratomileusis in patients with different degrees of myopia: a prospective study.

BACKGROUND: To investigate the difference between the predicted preoperative corneal ablation depth and the measured ablation depth for femtosecond laser in situ keratomileusis (FS-LASIK) in patients with different degrees of myopia, and to analyze the source of the difference. METHODS: A total of 55 patients (109 eyes) were included in this study. Multiple logistics regression was applied to analyze the sources affecting postoperative refractive outcomes. The difference between the preoperative predicted corneal ablation depth and the 1-day postoperative ablation depth in patients with different degrees of myopia was explored using linear regression. Corneal biomechanical parameters influencing error in ablation depth calculation were examined using multiple linear regression. RESULTS: One hundred and nine eyes were divided into low to moderate myopia (55 eyes, myopia of 6 D or less), high myopia (45 eyes, myopia ranging from 6 D to a maximum of 9 D), and very high myopia group (9 eyes, myopia greater than 9 D) based on preoperative refractive error (spherical equivalent). Postoperative visual outcomes were comparable among the three groups of patients, with no significant difference in uncorrected visual acuity (UCVA). We did find notable disparities in spherical equivalent (SE) and central corneal thickness (CCT) in patients with different degrees of myopia at 1 day postoperatively (all p < 0.001). Logistic regression analysis showed that error in ablation depth calculation was an independent risk factor for refractive outcomes one day after surgery (OR = 1.689, 95% CI: 1.366 - 2.089). There was a substantial discrepancy in error in ablation depth calculation at 1 day postoperatively between the three groups. The measured ablation depth of the laser platform was lower than the predicted ablation depth in the low to moderate myopia and very high myopia groups, but the opposite was true in the high myopia group. Pre-operative SE (p < 0.001) and corneal front minimum radius of curvature (Front Rmin) (p = 0.007) obviously influenced the error in ablation depth calculation. CONCLUSIONS: Error in ablation depth calculation values vary significantly between patients with different degrees of myopia and correlate highly with preoperative SE and Front Rmin. At the same time, the available evidence suggests that error in ablation depth calculation is an influential factor in postoperative refractive status, so it is imperative to control error in ablation depth calculation.

Quantitative Evaluation of the Normal Cervix, Cervical Cancer, and Cervical Precancerous Changes Via Real-Time Shear Wave Elastography.

OBJECTIVES: The present study aims to evaluate the clinical application values of ultrasound real-time shear wave elastography (SWE) in the diagnosis and differential diagnosis of cervical cancer (CC). METHODS: A total of 285 married female patients were screened and divided into three groups according to the results of the pathological examination and the cervical ThinPrep cytologic test: 1) the CC group (n = 94); 2) the cervical intraepithelial neoplasia (CIN) group (n = 91); and 3) the normal control group (n = 100). The maximum Young's modulus (Emax), mean Young's modulus (Emean), minimum Young's modulus (Emin), and Young's modulus stability (Esd) in each group were measured and statistically analyzed. RESULTS: There were no statistically significant differences in Emax, Emean, Emin, and Esd values between the anterior and posterior cervical walls, premenopausal and postmenopausal women, and nonparturient and parturient women in the normal control group. The Emax, Emean, Emin, and Esd values in the CIN group showed no statistically significant differences in different periods when compared with the control group. The differences between the normal control group and the CC group were statistically significant; the CC group showed no statistically significant differences in Emax, Emean, Emin, and Esd values at different clinical stages and in different pathological types. The cutoff value of Emax for CC diagnosis, which was of the highest accuracy (89.7%), was 43.48 kpa. CONCLUSION: Ultrasound real-time SWE can be applied to CC diagnosis.

Water-driven Successive Structural Transformation in a Two-Dimensional (2D) Lead-Free Hybrid Double Perovskite.

Hybrid organic-inorganic halide perovskites (HOIPs) have received continued interest for their structure diversity and potential application in optoelectronic, solar cells, nonlinear optics (NLO), and ferroelectrics. Structural symmetry breaking induced by water molecules in single-crystal-to-single-crystal (SCSC) transformations is beneficial to develop ferroelectrics or second-harmonic generation (SHG) materials. Along this line, a water-containing two-dimensional (2D) double perovskite, (C6H16N2)2AgBiBr8·H2O (1), was prepared. Acentric 1 suffered a twice SCSC transformation when subjected to dehydration and rehydration, where the new centric (C6H16N2)2AgBiBr8 (2) and acentric (C6H16N2)2AgBiBr8·0.5H2O (3) were generated. In contrast to the irreversible transformation from 1 to 2 (symmetry: P21 → Pmna), it is prominent that the reversible conversion of centric 2 to acentric 3 (symmetry: Pmna ↔ P21212). The result validated the effect of guest water on inducing structural transformation and symmetry breaking of 2D perovskites, inspiring further explorations on water-involved 2D materials.

FtNAC31, a Tartary buckwheat NAC transcription factor, enhances salt and drought tolerance in transgenic Arabidopsis.

Tartary buckwheat [Fagopyrum tataricum (L.) Gaertn.] is a pseudocereal with strongly abiotic resistance. NACs, one of the largest plant-specific transcription factors (TFs), are involved in various stress responses. However, the characteristics and regulatory mechanisms of NAC TFs remain unclarified clearly in Tartary buckwheat (TB). In this study, it validated that salt, drought, and abscisic acid (ABA) stress significantly up-regulated the expression of NAC TF gene FtNAC31. Its coding protein has a C-terminal transactivated domain and localized in the nucleus, suggesting that FtNAC31 might play a transcriptional activation role in TB. Notably, overexpression of FtNAC31 lowered the seed germination rate upon ABA treatment and enhanced the tolerance to salt and drought stress in transgenetic Arabidopsis. Furthermore, under various stresses, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in FtNAC31 overexpressed lines exhibited a sharp increase trend. Meanwhile, the expression levels of several stress-associated genes including RD29A, RD29B, RD22, DREB2B, NCED3, and POD1, were dramatically upregulated in lines overexpressing FtNAC31. Altogether, overproduction of FtNAC31 could enhance the resistance to salt and drought stresses in transgenic Arabidopsis, which most likely functioned in an ABA-dependent way.

Thermally induced charge transfer in a quinoid-bridged linear Cu3 compound.

Charge transfer always occurs in molecular valence tautomers, leading to the redistribution of electron density and exhibiting electrical, optical, and magnetic properties, and can be further controlled by multiple external stimuli such as temperature, light and electric field. The design of molecule-based materials capable of charge transfer remains a challenge. Herein, a linear Cu3 compound [(CH3)3NCH2CH2Br]2[Cu3L4(H2O)2] (H2L = chloranilic acid) (1) with a multi-center donor-acceptor architecture was constructed using the redox-active chloranilic acid quinoid ligand. Temperature-dependent dielectric measurement was performed to capture the charge transfer valence tautomer transition because it is difficult to detect this transition by crystal structure and magnetism analysis. Temperature-dependent XPS and EPR further confirmed that the charge transfer valence tautomer transition is based on the CuII-L2- to CuI-L-˙ multi-center charge transfer. Thus, the present work builds a charge transfer compound with a multi-center donor-acceptor architecture and proves that dielectric measurement is a very effective means to detect charge transfer.

[Analysis of projects funded by NSFC in field of Chinese medicine toxicology from 2012 to 2021].

This study mainly introduced the research on Chinese medicine toxicology funded by the National Natural Science Foundation of China(NSFC) in 2012-2021 and analyzed the research content. Furthermore, key research topics and characteristic research projects were discussed, such as the toxicity mechanism, relationship between toxicity and efficacy, toxicity-alleviating mechanisms, and new technology and methods. The review suggested that researchers should gain an in-depth understanding of the "toxicity" of Chinese me-dicine, turned to characteristic research topics, and build a toxicological research paradigm suited to the characteristics of Chinese medicine in project application.

Nocebo effect in multiple system atrophy: systematic review and meta-analysis of placebo-controlled clinical trials.

BACKGROUND: Nocebo effect is prevalent among neurological diseases, resulting in low adherence and treatment outcome. We sought to examine the nocebo effect in randomized controlled trials (RCTs) in multiple system atrophy (MSA). METHODS: We searched RCTs in MSA from Medline since September, 2021. RCTs for drug treatment conducted in adult MSA patients with more than 5 cases in each treatment arm were included. We assessed the number of dropout due to placebo intolerance. We also did a symptomatic/disease-modifying subgroup analysis based on two different treatment purposes. The STATA software was used for statistical analysis. Overall heterogeneity was assessed using the Cochran Q and I2. RESULTS: Data were extracted from 11 RCTs fulfilling our search criteria. Of 540 placebo-treated patients, 64.2% reported at least one adverse event (AE) and 7.5% reported dropout because of AEs. The chance of dropping out because of an AE and experiencing at least one AE did not differ between placebo and active drug treatment arms. Besides, the pooled nocebo dropout rate in the symptomatic subgroup was similar to that of the disease-modifying subgroup. CONCLUSION: In MSA RCTs, nocebo dropout rate was not at a low level among neurological disorders. Nocebo effect was an important reason of dropout because of AE in placebo and active drug treatment arms. Different treatment purposes may not influence nocebo effect.

A polar oxyhalogen-vanadate compound (C5NH13Cl)2VOCl4 with optical and two-staged dielectric switch behavior.

Polar organic-inorganic hybrid materials have been applied in ferroelectricity, as well as in devices based on nonlinear optical and piezoelectricity properties. Here, we used a rectangular pyramid structure of [VOCl4]2- to construct a polar compound (C5NH13Cl)2VOCl4 (1). Compound 1 crystallized in the monoclinic P21 space group. Coexistence of nonlinear optical switching behavior (space-group change from P21 to P21/n) and two-staged thermosensitive dielectric switching properties could be achieved under the stimulus of temperature. Our findings provide an effective approach for construction of polar materials.

Inorganic-Organic Hybrid Molecular Materials: From Multiferroic to Magnetoelectric.

Inorganic-organic hybrid molecular multiferroic and magnetoelectric materials, similar to multiferroic oxide compounds, have recently attracted increasing attention because they exhibit diverse architectures, a flexible framework, fascinating physics, and potential magnetoelectric functionalities in novel multifunctional devices such as energy transformation devices, sensors, and information storage systems. Herein, the classification of multiferroicity and magnetoelectricity is briefly outlined and then the recent advances in the multiferroicity and magnetoelectricity of inorganic-organic hybrid molecular materials, particularly magnetoelectricity and the relevant magnetoelectric mechanisms and their categories are summarized. In addition, a personal perspective and an outlook are provided.

Magnetodielectric Response in a Layered Mixed-Valence Ferrimagnetic Molecular Compound.

The magnetodielectric effect is closely related to multiferroic or magnetoelectric coupling; thus, it can be used to predict magnetoelectric coupling, especially in compounds with special magnetic properties. The magnetodielectric response can often be used to predict many interesting and meaningful physical coupling mechanisms. Therefore, fabricating magnetodielectric materials is an effective step toward the development of magnetoelectric materials. Herein, we synthesize the mixed-valence layered ferrimagnetic molecular compound (C6N2H14)FeIII2FeIIF8(HCOO)2 (1) and demonstrate that it exhibits both slow magnetic relaxation behavior and long-range magnetic order. This long-range order occurs because of the coexistence and competition between two typical magnetic interactions, namely, an FeIII-F-FeII superexchange and a long-distance superexchange FeII-O-C-O-FeIII-F-FeIII path in the interlayer and interchain spin frustration. Notably, this compound also demonstrates two abnormal dielectric relaxation processes: the first process is dominated by dynamic guest cations, while the other process is related to the increasing magnetic correlation. Over a wide temperature range below 170 K, the magnetodielectric effect reveals that the magnetic correlation maybe promotes electron dynamics and leads to magnetodielectric coupling. These findings pave a novel path for designing magnetodielectric molecular materials.

Application Value of Real-Time Shear Wave Elastography in Diagnosing the Depth of Infiltrating Muscular Layer of Endometrial Cancer.

OBJECTIVE: To explore the clinical value of real-time shear wave ultrasonic elastography in diagnosing the depth of infiltrating muscularis of endometrial cancer. METHODS: Seventy-one patients with stage I endometrial cancer infiltrating the myometrium and 37 patients with normal physical examination were enrolled and divided into three groups: endometrial cancer superficial muscle infiltration group, endometrial cancer deep muscle infiltration group, and normal control group. After completing 2-dimensional ultrasound examination, each patient switched to the real-time shear wave elastography mode to measure the elasticity values Emax, Emean, and Esd. RESULTS: For control group, comparison of elastic modulus values between superficial muscular layer near the intimal surface and the deep muscular layer near the serosa surface showed no difference (P > 0.05). For endometrial cancer superficial muscular infiltration group, significant difference was found regarding the elastic modulus values of infiltrated muscular layer and uninfiltrated muscular layer (Emax and Emean) without difference for Esd (P > 0.05). A significant difference of elastic modulus was observed between control group and deep myometrial infiltration group (P < 0.05) without difference of Emean or Emax but with difference of Esd. The accuracy in diagnosing muscular layer infiltration was 78.9% for Emax cutoff and 82.5% for Emean cutoff. The rate of using Emax ≥32.22 kPa or Emean ≥27.54 kPa as the ultrasound standard for diagnosing myometrium infiltration was 92.9%. The accuracy for the diagnosis of muscular layer infiltration was 96.1% for Emax cutoff, 94.1% for Emean cutoff and 86.3% for Esd cutoff. CONCLUSION: Real-time shear wave elastography is helpful to determine the depth of infiltrating myometrium of endometrial cancer.

MicroRNA-532-5p is a prognostic marker and inhibits the aggressive phenotypes of osteosarcoma through targeting CXCL2.

The dysregulation of miR-532-5p is involved in the development of several cancers. Nevertheless, the roles of miR-532-5p in osteosarcoma (OS) have yet to be illuminated. In the present study, we found that miR-532-5p was significantly downregulated in both OS tissues and cell lines. The low level of miR-532-5p was associated with advance clinical stage and poor overall survival in patient with OS. The functional experiments implied that upregulation of miR-532-5p restrained OS U2OS cell growth and metastatic ability in vitro; induced apoptosis, and impaired OS cell growth in vivo. Mechanistically, chemokine (C-X-C Motif) ligand 2 (CXCL2) was proved as a target gene of miR-532-5p. The inhibitory effects of miR-532-5p on OS cell were rescued by CXCL2 overexpression. Altogether, we demonstrated that miR-532-5p exerted tumor-inhibitory functions in OS cell via regulating CXCL2.

The Mechanism of the Magnetodielectric Response in a Molecule-Based Trinuclear Iron Cluster Material.

Magnetodielectric response mechanisms are critical for the rational design and synthesis of molecule-based magnetodielectric materials. Herein, the magnetodielectric response was investigated in the molecule-based material [Fe3 O(CH3 COO)6 (py)3 ](py) (1). Its magnetodielectric coefficient (MD) is -2.8 % for phase transition III and -4.1 % for phase transition I. Study of the mechanism of the magnetodielectric response in 1 reveals that its magnetodielectric response at phase transition I is induced by the charge-frustration of the trinuclear iron cluster, while that at phase transition III is attributed to the spin-frustration of the trinuclear iron cluster, providing a new route for the design of magnetodielectric materials.

Polar Molecule-Based Material with Optic-Electric Switching Constructed by Polar Anions.

Polar crystal structures have attracted more and more attention, due to their unique characteristics, such as ferroelectricity, piezoelectricity, and nonlinear optical property, etc. However, the construction of polar materials is always accidental, and finding an effective synthesis strategy to construct polar materials remains a challenge. Herein, inorganic-organic hybrid compounds of [C7H14N][FeCl4] (1) ([C7H14N] = quinuclidinium cation) and [C7H14N][GeCl3] (2) were prepared, respectively, to verify the beneficial effect of polar anions on the construction of polar crystals. Compound 1 crystallized in the Pbca space group, while 2 belongs to the P43 space group at room temperature. Investigation into the structure of 2 reveals that the polarity of 2 derives from the triangular pyramid structure of [GeX3]- with lone pair electrons. Meanwhile, 2 undergoes a phase transition from the P43 space group to the center Pm3m at 385 K, leading to the optic-electric switching property. Thus, the present work exhibits the advantage of [GeX3]- as the inorganic constituent component in the hybrid polar materials and provides an effective approach for the construction of a polar molecule-based crystal with a switchable property.

Saponins of Panax japonicus Confer Neuroprotection against Brain Aging through Mitochondrial Related Oxidative Stress and Autophagy in Rats.

BACKGROUND: Oxidative stress and mitochondrial dysfunction play a vital role in the pathogenesis of brain aging. Saponins from Panax japonicus (SPJ) have attracted much attention for their potential to attenuate age-related oxidative stress as the main ingredient in rhizomes of Panax japonicus. OBJECTIVE: This study aimed to investigate the neuroprotective effects of SPJ on natural aging rats as well as the underlying mechanisms regarding oxidative stress and mitochondrial pathway. METHODS: Sprague-Dawley rats were divided into control groups (3-, 9-, 15- and 24-month old groups) and SPJ-treated groups. For SPJ-treated groups, SPJ were orally administrated to 18-month old rats at doses of 10 mg/kg, 30 mg/kg and 60 mg/kg once daily. Control groups were given the same volume of saline. After the treatment with SPJ or saline for six months, the cortex and hippocampus were rapidly harvested and deposited at -80°C after the rats were decapitated under anesthesia. The neuroprotective effects of SPJ were estimated by histopathological observation, TUNEL detection, biochemical determination and western blotting. RESULTS: SPJ improved pathomorphological changes in neuronal cells and decreased apoptosis in the cortex and hippocampus of aging rats, increased the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), Na+/K+-ATPase, Ca2+-ATPase and Ca2+/Mg2+-ATPase whereas, decreased malondialdehyde (MDA) contents in the cortex of aging rats. Furthermore, the SPJ increased silent mating type information regulation 2 homolog-1 (SIRT1) protein expression, decreased acetylated level of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) in the cortex and hippocampus of aging rats, and reversed the aging-induced decline of Forkhead box O3 (Foxo3a), Superoxide Dismutase 2 (SOD2), microtubule-associated protein light chain 3 (LC3II) and Beclin1 levels in the cortex and hippocampus. CONCLUSION: Our data showed that SPJ conferred neuroprotection partly through the regulation of oxidative stress and mitochondria-related pathways in aging rats.

Impact of co-blocking the costimulatory signals on immune-related genes after high-risk rabbit corneal allograft using 2nd-generation DNA sequencing technology.

The aim of this study was to evaluate the impact and mechanism of co-blocking of costimulatory signals CD28-B7-CD40-CD40L during immune allograft rejection. Forty-eight recipient rabbits were prepared as a high-risk corneal allograft model. After surgery, the animals were randomly divided into: control group, MR1 group, anti-B7 group, and co-blocking group (n=12, each group). Subconjunctival injection was first performed on the allograft surgery day until post-surgery day five. Four weeks later, or when immune rejection occurred, the cornea was sampled to detect and analyze the gene spectrum. The survival time in the co-blocking group was significantly longer than that in the other three groups (p < 0.05). Gene expression analysis revealed that the expression of genes associated with immune rejection, interleukin (IL)-1α, IL-1ß, intercellular cell adhesion molecule-1, and IL-2 was down-regulated in the co-blocking group, while IL-10 was up-regulated, but the changes in nuclear factor-κB and interferon-γ were not significant. In conclusion, the co-blocking of costimulatory signals can significantly reduce genes that promote corneal allograft rejection. The inhibition of corneal allograft rejection gene expression was significantly enhanced. These gene expression results can explain the conclusion of previous work at the genetic level.

Coexistence of Magnetic-Optic-Electric Triple Switching and Thermal Energy Storage in a Multifunctional Plastic Crystal of Trimethylchloromethyl Ammonium Tetrachloroferrate(III).

Driven by the rapidly increasing demand for technological applications, multifunctional materials have been one important research area, which are expected to enhance the capacity and versatility of materials in various applications. Nevertheless, combining more than three functions in one molecular compound is still a challenge. Molecular solid-solid phase transition materials could exhibit switchable properties, which could have potential applications such as switches, sensors, and memory devices. However, these switchable molecular materials are rarely researched as thermal energy storage materials. In this work, we report the coexistence of thermal energy storage and magnetic-optic-electric triple switching in a plastic crystal, trimethylchloromethyl ammonium tetrachloroferrate(III), ([(CH3)3NCH2Cl][FeCl4], referred to as 1). 1 undergoes plastic phase transition at near room temperature (326 K) induced by the order-disorder of the ions. The magnetic-optic-electric triple switching in 1 could be triggered by temperature stimuli near room temperature. Meanwhile, with utilization of large latent heat during the phase transition process and sensible heat, the energy storage in 1 is up to 107 J g-1 from 293 to 343 K, demonstrating its thermal energy storage application in solar energy systems and industrial sectors. This work particularly exhibits the advantages of plastic molecular materials as thermal energy storage materials and introduces the thermal energy storage into the multi-switchable plastic phase transition molecular materials, which will give extra flexibility for the design of new types of multifunctional materials.

[Protective effect of Wuzi Yanzong recipe on testicular germ cell apoptosis in natural ageing rats through endoplasmic reticulum stress].

To study the protective effects of Wuzi Yanzong recipe on testis germ cell apoptosis in natural ageing rats through endoplasmic reticulum stress (ERS), 16-month-old male SPF grade SD rats were randomly divided into three groups: ageing model group, and low and high-dose Wuzi Yanzong recipe groups (WZ, 1 and 4 g·kg⁻¹), with 10 rats in each group. In addition, 2-month-old SD male rats were used as adult control group. The ageing model group and the adult control group were fed with normal diet for 4 months. WZ groups were given the medicated feed for 4 months. After fasting for 12 hours, the rats were put to death. Then, the testes were immediately collected. The change of testicular tissue morphology was observed by HE staining. The expression levels of ER stress-related proteins GRP78, p-PERK, p-eif2α, ATF4, p-IRE1, XBP1, ATF6 and apoptosis-related proteins CHOP, caspase12 and p-JNK in testes were detected by Western blot. Compared with the ageing model group, Wuzi Yanzong recipe alleviated the morphological changes of testicular tissue. Western blot results showed that Wuzi Yanzong recipe significantly increased the expression levels of endoplasmic reticulum stress-related proteins GRP78, p-PERK, p-eif2α, ATF4, p-IRE1, XBP1, ATF6 and significantly decreased the expression levels of endoplasmic reticulum-induced apoptosis-related proteins CHOP, caspase 12 and p-JNK. In conclusion, Wuzi Yanzong recipe can alleviate the ageing-related apoptosis of testicular germ cells in natural ageing rats by regulating endoplasmic reticulum stress.