Electrochemiluminescence of Ultrasmall Silica Nanoparticles from Size Modulation and Multipath Surface State Adjustment for Ultrasensitive HIV-DNA Fragment Detection.

Here, ultrasmall SiO2 nanoparticles (u-SiO2 NPs, <5 nm) with obvious electrochemiluminescence (ECL) phenomenon, which was absent for conventional silica nanoparticles (c-SiO2 NPs), were reported. In a finite ultrasmall volume, the u-SiO2 NPs exhibited increasing ground state energy and higher optical absorption strength due to the electron-hole confinement model and favored catalyzing the reaction through the rapid diffusion of bulk charge, resulting in apparent ECL emission. Then, Zn2+-induced u-SiO2 nanoaggregates (Zn/u-SiO2-Ov nAGG) were synthesized and exhibited improved ECL performance via multipath surface state adjustment of u-SiO2 from several aspects, including aggregation-induced ECL, the generation of oxygen vacancy (Ov), and more positive surface charge. In addition, an ECL biosensor was constructed for ultrasensitive human immunodeficiency virus-related deoxyribonucleic acid detection from 100 aM to 1 nM with a low limit of 50.48 aM, combining the ECL luminescence of Zn/u-SiO2-Ov nAGG with three-dimensional DNA nanomachine-mediated multioutput amplification for enhanced accuracy and sensitivity compared to the single-output method. Therefore, exploring the ECL of ultrasmall nanoparticles via the adjustment of size and surface state provided a valuable indication to a wider investigation and application of novel ECL materials for clinical diagnostic.

Relations between school climates and bullying behaviors in Chinese adolescents: The mediating role of prosocial tendency.

This research investigated the relationships between school climates and bullying behaviors in Chinese adolescents, and tested the mediating effect of prosocial tendency according to the seesaw effect. School climates were operationalized using three constructs: subjective diversity of student development goals, teacher support, and peer trust. Bullying behaviors included traditional (i.e., physical, nonphysical, and relational) and cyber bullying behaviors. We recruited 538 adolescents from three schools in Beijing, China (286 girls, 252 boys; average age = 12.47) and asked them to fill out the surveys measuring school climates and prosocial tendency at the outset and to report school bullying behaviors three months later. The results showed that subjective diversity of student development goals and peer trust were directly associated with less cyber bullying behavior. Moreover, teacher support and peer trust were indirectly associated with less traditional bullying behaviors via prosocial tendency. Our findings extend the existing literature on the relationships between school climates and bullying behaviors by incorporating different types of bullying behaviors, concentrating on Chinese adolescents from a cultural viewpoint, and tapping into the underlying mechanism via revealing prosocial tendency as a mediator. Theoretical and empirical contributions of this study, as well as practical implications are discussed.

Diquat causes mouse testis injury through inducing heme oxygenase-1-mediated ferroptosis in spermatogonia.

Diquat dibromide (DQ) is a globally used herbicide in agriculture, and its overuse poses an important public health issue, including male reproductive toxicity in mammals. However, the effects and molecular mechanisms of DQ on testes are limited. In vivo experiments, mice were intraperitoneally injected with 8 or 10 mg/kg/ day of DQ for 28 days. It has been found that heme oxygenase-1 (HO-1) mediates DQ-induced ferroptosis in mouse spermatogonia, thereby damaging testicular development and spermatogenesis. Histopathologically, we found that DQ exposure caused seminiferous tubule disorders, reduced germ cells, and increased sperm malformation, in mice. Reactive oxygen species (ROS) staining of frozen section and transmission electron microscopy (TEM) displayed DQ promoted ROS generation and mitochondrial morphology alterations in mouse testes, suggesting that DQ treatment induced testicular oxidative stress. Subsequent RNA-sequencing further showed that DQ treatment might trigger ferroptosis pathway, attributed to disturbed glutathione metabolism and iron homeostasis in spermatogonia cells in vitro. Consistently, results of western blotting, measurements of MDA and ferrous iron, and ROS staining confirmed that DQ increased oxidative stress and lipid peroxidation, and accelerated ferrous iron accumulation both in vitro and in vivo. Moreover, inhibition of ferroptosis by deferoxamine (DFO) markedly ameliorated DQ-induced cell death and dysfunction. By RNA-sequencing, we found that the expression of HO-1 was significantly upregulated in DQ-treated spermatogonia, while ZnPP (a specific inhibitor of HO-1) blocked spermatogonia ferroptosis by balancing intracellular iron homeostasis. In mice, administration of the ferroptosis inhibitor ferrostatin-1 effectively restored the increase of HO-1 levels in the spermatogonia, prevented spermatogonia death, and alleviated the spermatogenesis disorders induced by DQ. Overall, these findings suggest that HO-1 mediates DQ-induced spermatogonia ferroptosis in mouse testes, and targeting HO-1 may be an effective protective strategy against male reproductive disorders induced by pesticides in agriculture.

mNGS helped diagnose scrub typhus-associated HLH in children: a report of two cases.

Background: Scrub typhus, caused by the Orientia tsutsugamushi (Ot), is a widespread vector-borne disease transmitted by chigger mites. Hemophagocytic lymphohistiocytosis (HLH) is considered to be one of the potentially severe complications. The diagnosis of scrub typhus-associated HLH may be overlooked due to the non-specific clinical characteristics and the absence of pathognomonic eschar. Case presentation: We obtained clinical data from two patients in the South of Sichuan, China. The first case involved a 6-year-old girl who exhibited an unexplained fever and was initially diagnosed with sepsis, HLH, and pulmonary infection. The other patient presented a more severe condition characterized by multiple organ dysfunction and was initially diagnosed with septic shock, sepsis, HLH, acute kidney injury (AKI), and pulmonary infection. At first, a specific examination for scrub typhus was not performed due to the absence of a characteristic eschar. Conventional peripheral blood cultures yielded negative results in both patients, and neither of them responded to routine antibiotics. Fortunately, the causative pathogen Orientia tsutsugamushi (Ot) was detected in the plasma samples of both patients using metagenomics next-generation sequencing (mNGS) and further confirmed by polymerase chain reaction. Subsequently, they both were treated with doxycycline and recovered quickly. Conclusion: The unbiased mNGS provided a clinically actionable diagnosis for an uncommon pathogen-associated infectious disease that had previously evaded conventional diagnostic approaches.

Atomically Precise Single-Site Catalysts via Exsolution in a Polyoxometalate-Metal-Organic-Framework Architecture.

Single-site catalysts (SSCs) achieve a high catalytic performance through atomically dispersed active sites. A challenge facing the development of SSCs is aggregation of active catalytic species. Reducing the loading of these sites to very low levels is a common strategy to mitigate aggregation and sintering; however, this limits the tools that can be used to characterize the SSCs. Here we report a sintering-resistant SSC with high loading that is achieved by incorporating Anderson-Evans polyoxometalate clusters (POMs, MMo6O24, M = Rh/Pt) within NU-1000, a Zr-based metal-organic framework (MOF). The dual confinement provided by isolating the active site within the POM, then isolating the POMs within the MOF, facilitates the formation of isolated noble metal sites with low coordination numbers via exsolution from the POM during activation. The high loading (up to 3.2 wt %) that can be achieved without sintering allowed the local structure transformation in the POM cluster and the surrounding MOF to be evaluated using in situ X-ray scattering with pair distribution function (PDF) analysis. Notably, the Rh/Pt···Mo distance in the active catalyst is shorter than the M···M bond lengths in the respective bulk metals. Models of the active cluster structure were identified based on the PDF data with complementary computation and X-ray absorption spectroscopy analysis.

From the dual-dimensional perspective of employee mindfulness and superior trust, explore the influence mechanism of negative workplace gossip on work engagement.

Introduction: As a common phenomenon of workplace negative gossip in organizations, how it affects employees' work engagement is not yet clear, nor what methods can be used to mitigate its negative impact on employees' work engagement. Methods: Based on Conservation of Resource Theory, this study obtained 334 valid employee samples from mainland China enterprises through a three-time lagged research design and explored the mechanism of negative workplace gossip on work engagement from the dual perspectives of employees and supervisors. Results: The results show that: (1) Negative workplace gossip negatively affects employee work engagement. (2) Professional commitment plays a mediating role between negative workplace gossip and employee work engagement. (3) Employee mindfulness negatively moderates the negative impact of workplace negative gossip on professional commitment; superior trust negatively moderates the negative impact of workplace negative gossip on professional commitment. (4) Employee mindfulness and superior trust are further weakened to moderate the negative indirect impact of workplace negative gossip on employee work engagement through professional commitment, and this negative indirect impact is weaker when employees have a higher degree of mindfulness and higher trust in superiors. Discussion: It proposes effective strategies for managing workplace gossip to harness its positive influence and offer practical guidance to enhance employee work engagement.

Geometry and Chemistry: Influence of Pore Functionalization on Molecular Transport and Diffusion in Solvent-Filled Zirconium Metal-Organic Frameworks.

Postsynthetic modification (PSM) of metal-organic frameworks (MOFs) enables incorporation of diverse functionalities in pores for chemical separations, drug delivery, and heterogeneous catalysis. However, the effect of PSM on molecular transport, which is essential for most applications of MOFs, has been rarely studied. In this paper, we used perfluoroalkane-functionalized Zr-MOF NU-1008 as a platform to systematically interrogate transport processes and mechanisms in solvated pores. We anchored perfluoroalkanes onto NU-1008 nodes by solvent-assisted ligand incorporation (SALI-n, with n = 3, 5, 7, and 9 denoting the number of fluorinated carbons). Transport of a luminescent molecule, BODIPY, through individual crystallites of four versions of methanol-filled SALI-n was monitored by confocal fluorescence microscopy as a function of time and location. In comparison with the parent NU-1008, the diffusivity of the probe molecules within SALI-n declined by 2- to 7-fold depending on chain length and loading, presumably due to the reduction in pore diameter or adsorptive interactions with perfluoroalkyl chains. Atomistic simulations were performed to uncover the microscopic behavior of the BODIPY diffusion in SALI-n. The perfluoroalkyl chains are observed to stay close to the pore walls, instead of extending toward the pore center. BODIPY molecules, which preferably interact with linkers, were pushed to the interior of the channels as the chain length increased, resulting in solvated diffusion and minor differences in the short-time mobility of BODIPY in SALI-n. This suggested that the observed decline of transport diffusivity in SALI-n mainly stemmed from the reduction in the pore size when these flexible chains are present. We anticipate that this proof of concept will assist in understanding how pore functionalization can physically and chemically affect mass transport in MOFs and will be useful in further guiding the design of PSM to realize the optimal performance of MOFs for various applications.

A primary pediatric acute myelomonocytic leukemia with t(3;21)(q26;q22): A case report.

RATIONALE: The rare t(3;21)(q26;q22) translocation results in gene fusion and generates multiple fusion transcripts, which are typically associated with therapy-related myelodysplastic syndrome, acute myeloid leukemia, and chronic myelogenous leukemia. Here, we report a rare case of de novo acute myelomonocytic leukemia in a young child with t(3;21)(q26;q22). PATIENT CONCERNS: A 2-and-a-half-year-old female patient presented with abdominal pain, cough, paleness, and fever for 3 weeks, without any history of malignant diseases. DIAGNOSES: Chest computed tomography revealed pneumonia. Bone marrow smear confirmed acute myelomonocytic leukemia. Cytogenetic analysis and Sanger sequencing identified RUNX1-MECOM and RUNX1-RPL22 fusion genes as a result of t(3;21)(q26;q22). INTERVENTIONS: The patient received 3 courses of chemotherapy, but bone marrow smear examination showed no remission. According to the wishes of the patient family, the allogeneic hematopoietic stem cell transplantation (Allo-HSCT) was chosen. OUTCOMES: The patient did not experience any adverse reactions after Allo-HSCT. The red blood cells and platelets increased without transfusion. The pneumonia recovered after antibiotic treatment. LESSONS: The patient recovered well after Allo-HSCT. Therefore, for patients with RUNX1-MECOM and RUNX1-RPL22 fusion genes, transplantation may be a good choice when chemotherapy is not effective.

Molecular epidemiology and clinical characteristics of enteroviruses associated HFMD in Chengdu, China, 2013-2022.

OBJECTIVES: This study aims to investigate molecular epidemiology and clinical characteristics of enterovirus associated hand-foot-mouth disease (HFMD) in Chengdu, China, 2013-2022. Monitoring the molecular epidemiology and clinical features of HFMD for up to 10 years may provide some ideas for future protection and control measures. METHODS: We conducted a retrospective analysis of the medical records of all patients with laboratory-confirmed HFMD-related enterovirus infection at the West China Second University Hospital from January 2013 to December 2022. We described the characteristics in serotype, age, sex distribution and hospitalization of enterovirus infection cases using data analysis and graphic description. RESULTS: A total of 29,861 laboratory-confirmed cases of HFMD-related enterovirus infection were reported from 2013 to 2022. There was a significant reduction in the number and proportion of EV-A71 cases after 2016, from 1713 cases (13.60%) in 2013-2015 to 150 cases (1.83%) in 2017-2019. During the COVID-19 pandemic, EV-A71 cases even disappeared. The proportion of CV-A16 cases decreased from 13.96% in 2013-2015 to 10.84% in 2017-2019 and then to 4.54% in 2020-2022. Other (non-EV-A71 and non-CV-A16) serotypes accounted for 95.45% during 2020-2022, with CV-A6 accounting for 50.39% and CV-A10 accounting for 10.81%. Thus, CV-A6 and CV-A10 became the main prevalent serotypes. Furthermore, There was no significant difference in the enterovirus prevalence rate between males and females. The hospitalization rate of EV-A71 patients was higher that of other serotypes. In general, the proportion of HFMD hospitalizations caused by other pathogens except for EV-A71, CV-A16, CV-A10 and CV-A16 was second only to that caused by EV-A71. The proportion of children over 4 years old infected with enterovirus increased. CONCLUSION: The incidence of HFMD associated with enterovirus infection has decreased significantly and CV-A6 has been the main pathogen of HFMD in Chengdu area in recent years. The potential for additional hospitalizations for other untested enterovirus serotypes suggested that attention should also be paid to the harms of infections with unknown enterovirus serotypes. Children with HFMD were older. The development of new diagnostic reagents and vaccines may play an important role in the prevention and control of enterovirus infection.

Fabrication of sodium alginate-doped carbon dot composite hydrogel and its application for La (III) adsorption and enhanced the removal of phosphorus.

Adsorption is an effective method for the removal of hazardous substances from wastewater. In this work, a low-cost and environmental-friendly composite hydrogel material of sodium alginate doped with nitrogen doped carbon dots (SA@NCDs) was fabricated by impregnation for lanthanide and enhanced phosphorus adsorption in wastewater. The effects of NCDs doping amount, dosage, pH, initial solution concentration, adsorption time and temperature on the process of La (III) adsorption by SA@NCDs were investigated. The adsorption isotherms fitted to Langmuir isotherm model (R2 = 0.9970-0.9989) and the adsorption kinetics followed pseudo-second-order kinetic model (R2 = 0.9992). The maximum adsorption capacity of the adsorbent for La (III) was 217.39 mg/g according to the Langmuir model at 298.15 K. After five cycles, the removal efficiency of La (III) adsorbed by SA@NCDs was still 85.1%. Moreover, the loaded La (III) enhanced the adsorption of phosphorus. The La (III)-SA@NCDs-5 hydrogel adsorbent greatly improved the adsorption capacity for phosphorus compared with the La (III)-free adsorbent, and the adsorption amount can reach 9.64 mg-P/g. The SA@NCDs complex hydrogels for rare earth adsorption were prepared by introducing NCDs rich in amino group into SA hydrogels. The introduction of NCDs increases the adsorption sites of hydrogels, and also overcomes the problem that NCDs itself is difficult to recover in wastewater treatment applications. The lanthanide adsorbed material has a stable structure and can be used to remove phosphorus to deal with waste using the waste. It indicates the SA@NCDs hydrogel composite adsorbent have good potential for wastewater treatment.

Framework-Topology-Controlled Singlet Fission in Metal-Organic Frameworks.

Singlet fission (SF) has been explored as a viable route to improve photovoltaic performance by producing more excitons. Efficient SF is achieved through a high degree of interchromophoric coupling that facilitates electron superexchange to generate triplet pairs. However, strongly coupled chromophores often form excimers that can serve as an SF intermediate or a low-energy trap site. The succeeding decoherence process, however, requires an optimum electronic coupling to facilitate the isolation of triplet production from the initially prepared correlated triplet pair. Conformational flexibility and dielectric modulation can provide a means to tune the SF mechanism and efficiency by modulating the interchromophoric electronic interaction. Such a strategy cannot be easily adopted in densely stacked traditional organic solids. Here, we show that the assembly of the SF-active chromophores around well-defined pores of solution-stable metal-organic frameworks (MOFs) can be a great platform for a modular SF process. A series of three new MOFs, built out from 9,10-bis(ethynylenephenyl)anthracene-derived struts, show a topology-defined packing density and conformational flexibility of the anthracene core to dictate the SF mechanism. Various steady-state and transient spectroscopic data suggest that the initially prepared singlet population can prefer either an excimer-mediated SF or a direct SF (both through a virtual charge-transfer (CT) state). These solution-stable frameworks offer the tunability of the dielectric environment to facilitate the SF process by stabilizing the CT state. Given that MOFs are a great platform for various photophysical and photochemical developments, generating a large population of long-lived triplets can expand their utilities in various photon energy conversion schemes.

Leishmania donovani visceral leishmaniasis diagnosed by metagenomics next-generation sequencing in an infant with acute lymphoblastic leukemia: a case report.

Background: Visceral leishmaniasis (VL) is a neglected vector-borne tropical disease caused by Leishmania donovani (L. donovani) and Leishmania infantum (L. infantum). Due to the very small dimensions of the protozoa impounded within blood cells and reticuloendothelial structure, diagnosing VL remains challenging. Case presentation: Herein, we reported a case of VL in a 17-month-old boy with acute lymphoblastic leukemia (ALL). The patient was admitted to West China Second University Hospital, Sichuan University, due to repeated fever after chemotherapy. After admission, chemotherapy-related bone marrow suppression and infection were suspected based on clinical symptoms and laboratory test results. However, there was no growth in the conventional peripheral blood culture, and the patient was unresponsive to routine antibiotics. Metagenomics next-generation sequencing (mNGS) of peripheral blood identified 196123 L. donovani reads, followed by Leishmania spp amastigotes using cytomorphology examination of the bone marrow specimen. The patient was given pentavalent antimonials as parasite-resistant therapy for 10 days. After the initial treatment, 356 L. donovani reads were still found in peripheral blood by mNGS. Subsequently, the anti-leishmanial drug amphotericin B was administrated as rescue therapy, and the patient was discharged after a clinical cure. Conclusion: Our results indicated that leishmaniasis still exists in China. Unbiased mNGS provided a clinically actionable diagnosis of a specific infectious disease from an uncommon pathogen that eluded conventional testing.

Triplet Generation Through Singlet Fission in Metal-Organic Framework: An Alternative Route to Inefficient Singlet-Triplet Intersystem Crossing.

High quantum yield triplets, populated by initially prepared excited singlets, are desired for various energy conversion schemes in solid working compositions like porous MOFs. However, a large disparity in the distribution of the excitonic center of mass, singlet-triplet intersystem crossing (ISC) in such assemblies is inhibited, so much so that a carboxy-coordinated zirconium heavy metal ion cannot effectively facilitate the ISC through spin-orbit coupling. Circumventing this sluggish ISC, singlet fission (SF) is explored as a viable route to generating triplets in solution-stable MOFs. Efficient SF is achieved through a high degree of interchromophoric coupling that facilitates electron super-exchange to generate triplet pairs. Here we show that a predesigned chromophoric linker with extremely poor ISC efficiency (kISC ) but E S 1 ≥ 2 E T 1 ${{E}_{{S}_{1}}\ge {2E}_{{T}_{1}}}$ form triplets in MOF in contrast to the frameworks that are built from linkers with sizable kISC but E S 1 ≤ 2 E T 1 ${{E}_{{S}_{1}}\le {2E}_{{T}_{1}}}$ . This work opens a new photophysical and photochemical avenue in MOF chemistry and utility in energy conversion schemes.

BMSC-derived extracellular vesicles promoted osteogenesis via Axin2 inhibition by delivering MiR-16-5p.

Osteoporosis (OP) is a systemic bone disease caused by an imbalance in osteogenesis and osteoclastic resorption. Extracellular vesicles (EVs)-encapsulated miRNAs from bone mesenchymal stem cells (BMSCs) have been reported to participate in osteogenesis. MiR-16-5p is one of the miRNAs that regulates osteogenic differentiation; however, studies have shown that its role in osteogenesis is controversial. Thus, this study aims to investigate the role of miR-16-5p from BMSC-derived extracellular vesicles (EVs) in osteogenic differentiation and uncover the underlying mechanisms. In this study, we used an ovariectomized (OVX) mouse model and an H2O2-treated BMSCs model to investigate the effects of BMSC-derived EVs and EV-encapsulated miR-16-5p on OP and the underlying mechanisms. Our results proved that the miR-16-5p level was significantly decreased in H2O2-treated BMSCs, bone tissues of OVX mice, and lumbar lamina tissues from osteoporotic women. EVs-encapsulated miR-16-5p from BMSCs could promote osteogenic differentiation. Moreover, the miR-16-5p mimics promoted osteogenic differentiation of H2O2-treated BMSCs, and the effects exerted by miR-16-5p were mediated by targeting Axin2, a scaffolding protein of GSK3ß that negatively regulates the Wnt/ß-catenin signaling pathway. This study provides evidence that EVs-encapsulated miR-16-5p from BMSCs could promote osteogenic differentiation by repressing Axin2.

Synthetic Access to a Framework-Stabilized and Fully Sulfided Analogue of an Anderson Polyoxometalate that is Catalytically Competent for Reduction Reactions.

Polyoxometalates (POMs) featuring 7, 12, 18, or more redox-accessible transition metal ions are ubiquitous as selective catalysts, especially for oxidation reactions. The corresponding synthetic and catalytic chemistry of stable, discrete, capping-ligand-free polythiometalates (PTMs), which could be especially attractive for reduction reactions, is much less well developed. Among the challenges are the propensity of PTMs to agglomerate and the tendency for agglomeration to block reactant access of catalyst active sites. Nevertheless, the pervasive presence of transition metal sulfur clusters metalloenzymes or cofactors that catalyze reduction reactions and the justifiable proliferation of studies of two-dimensional (2D) metal-chalcogenides as reduction catalysts point to the promise of well-defined and controllable PTMs as reduction catalysts. Here, we report the fabrication of agglomeration-immune, reactant-accessible, capping-ligand-free CoIIMo6IVS24n- clusters as periodic arrays in a water-stable, hierarchically porous Zr-metal-organic framework (MOF; NU1K) by first installing a disk-like Anderson polyoxometalate, CoIIIMo6VIO24m-, in size-matched micropores where the siting is established via difference electron density (DED) X-ray diffraction (XRD) experiments. Flowing H2S, while heating, reduces molybdenum(VI) ions to Mo(IV) and quantitatively replaces oxygen anions with sulfur anions (S2-, HS-, S22-). DED maps show that MOF-templated POM-to-PTM conversion leaves clusters individually isolated in open-channel-connected micropores. The structure of the immobilized cluster as determined, in part, by X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure (XAFS) analysis, and pair distribution function (PDF) analysis of total X-ray scattering agrees well with the theoretically simulated structure. PTM@MOF displays both electrocatalytic and photocatalytic competency for hydrogen evolution. Nevertheless, the initially installed PTM appears to be a precatalyst, gaining competency only after the loss of ∼3 to 6 sulfurs and exposure to hydride-forming metal ions.

Melatonin Ameliorates Diquat-Induced Testicular Toxicity via Reducing Oxidative Stress, Inhibiting Apoptosis, and Maintaining the Integrity of Blood-Testis Barrier in Mice.

Diquat is a fast, potent, and widely used bipyridine herbicide in agriculture and it induces oxidative stress in several animal models. However, its genotoxic effects on the male reproductive system remain unclear. Melatonin is an effective free-radical scavenger, which has antioxidant and anti-apoptotic properties and can protect the testes against oxidative damage. This study aimed to investigate the therapeutic effects of melatonin on diquat-induced testicular injury in mice. The results showed melatonin treatment alleviated diquat-induced testicular injury, including inhibited spermatogenesis, increased sperm malformations, declined testosterone level and decreased fertility. Specifically, melatonin therapy countered diquat-induced oxidative stress by increasing production of the antioxidant enzymes GPX1 and SOD1. Melatonin treatment also attenuated diquat-induced spermatogonia apoptosis in vivo and in vitro by modulating the expression of apoptosis-related proteins, including P53, Cleaved-Caspase3, and Bax/Bcl2. Moreover, melatonin restored the blood-testicular barrier by promoting the expression of Sertoli cell junction proteins and maintaining the ordered distribution of ZO-1. These findings indicate that melatonin protects the testes against diquat-induced damage by reducing oxidative stress, inhibiting apoptosis, and maintaining the integrity of the blood-testis barrier in mice. This study provides a theoretical basis for further research to protect male reproductive health from agricultural pesticides.

Isorhamnetin protects porcine oocytes from zearalenone-induced reproductive toxicity through the PI3K/Akt signaling pathway.

BACKGROUND: Zearalenone (ZEA) widely exists in moldy grains, which seriously destroys the fertility of females. Isorhamnetin, a natural flavonoid, has extensive of pharmacological activities. However, the beneficial effect and the underlying molecular mechanism of isorhamnetin involvement in ZEA-induced porcine oocyte damage have not been investigated. METHODS: Oocytes were treated with different concentrations of ZEA (3, 5, 8 and 10 µmol/L) and isorhamnetin (5, 10, 20 and 30 µmol/L) for 44 h at 39 â„ƒ. ZEA (5 µmol/L) and isorhamnetin (10 µmol/L) were selected for subsequent studies. Polar body exclusion rate, apoptosis rate and apoptosis related proteins, ROS levels and SOD2 protein, mitochondrial membrane potential and distribution, endoplasmic reticulum distribution and proteins expression, and PI3K, Akt and p-Akt proteins expression of oocytes were detected. In addition, the effect of PI3K antagonist (LY294002) on oocyte nuclear maturation and apoptosis were used to determine the involvement of PI3K/Akt signaling pathway. RESULTS: Our findings showed that ZEA exposure damaged oocytes and isorhamnetin therapy restored the developmental capability of porcine oocytes. Isorhamnetin promoted polar body extrusion rate to rescue ZEA-induced meiotic arrest in porcine oocytes. Isorhamnetin alleviated ZEA-induced oxidative stress by stimulating SOD2 protein expression and inhibiting ROS production. Moreover, isorhamnetin enhanced normal mitochondrial distribution and mitochondrial membrane potential to prevent mitochondrial dysfunction induced by ZEA. Changing the expression of endoplasmic reticulum stress-related marker proteins (CHOP, GRP78) and the distribution rate of normal endoplasmic reticulum showed that isorhamnetin relieved ZEA-caused endoplasmic reticulum stress. Mechanistically, isorhamnetin decreased Bax/Bcl-2 protein expression and inhibited ZEA-induced apoptosis through PI3K/Akt signaling pathway. CONCLUSIONS: Collectively, these results suggest that isorhamnetin protects oocytes from ZEA-caused damage through PI3K/Akt signaling pathway, which enhances meiotic maturation and mitochondrial function, and inhibits early apoptosis, oxidative stress and endoplasmic reticulum stress in porcine oocytes. Our study provides a new strategy for solving the reproductive toxicity induced by ZEA and treating woman infertility. A possible mechanism by which isorhamnetin protected porcine oocytes from ZEA-induced damage. Isorhamnetin inhibited meiosis arrest and apoptosis of porcine oocytes induced by ZEA through the PI3K/Akt signaling pathway. Moreover, isorhamnetin repaired ZEA-induced oocyte damage by alleviating oxidative stress, mitochondrial dysfunction and ER stress.

Isomer of NU-1000 with a Blocking c-pore Exhibits High Water-Vapor Uptake Capacity and Greatly Enhanced Cycle Stability.

Chemically and hydrolytically stable metal-organic frameworks (MOFs) have shown great potential for many water-adsorption-related applications. However, MOFs with large pores that show high water-uptake capacity and high hydrolytic and mechanical cycle stability are rare. Through a deliberate adjustment of the linker of a typical zirconium-based MOF (Zr-MOF) (NU-1000), a new isomer of NU-1000 with blocked c-pores, but large mesopores was successfully synthesized. This new isomer, ISO-NU-1000, exhibits excellent water stability, one of the highest water vapor uptake capacities, and excellent cycle stability, making it a promising candidate for water-vapor-sorption-based applications such as water-adsorption-driven heat transfer. We find that the high water-cycling stability of ISO-NU-1000 is traceable to its blocking c-pore that hinders the hydrolysis of node-coordinating formate in the c-pore area and thereby prevents the introduction of node aqua and terminal hydroxo ligands. With the absence of these ligands and their ability to hydrogen-bond to channel-located water molecules, the strength of guest (water)/host (MOF) interactions is diminished and the absolute magnitude of the capillary force exerted by water during its evacuation from MOF channels is attenuated. The attenuation leaves the MOF capable of resisting pore collapse, capacity loss, and crystallinity loss during repetitive evaporative removal (and re-introduction) of water from pores.

Isorhamnetin protects zearalenone-induced damage via the PI3K/Akt signaling pathway in porcine ovarian granulosa cells.

Zearalenone (ZEA) is widely derived from moldy cereal grain, which has adverse effects on animal reproduction. In particular, pigs are more sensitive to ZEA-induced toxicity than other animals. Isorhamnetin has extensive pharmacological activity. However, the role of isorhamnetin in ZEA-induced cytotoxicity remains unclear. This study was designed to investigate the therapeutic effect of isorhamnetin on ZEA-induced damage in porcine ovarian granulosa cells and elucidate its molecular mechanism. Two experiments were conducted, where a minimum of 3 biological replicates were used for each treatment. In Exp. 1, ovarian granulosa cells were treated with different concentrations of isorhamnetin (1, 5, 10, 20 and 30 µmol/L) and ZEA (0, 10, 30, 60, 90 and 120 µmol/L) for 24 h. Our results indicated that 60 µmol/L ZEA (half-maximal inhibitory concentration value) and 20 µmol/L isorhamnetin (the most effective concentration against ZEA-induced cytotoxicity) were optimum concentrations. In Exp. 2, ovarian granulosa cells were treated with isorhamnetin (20 µmol/L) for 2 h, before treatment with ZEA (60 µmol/L) for 24 h. Apoptosis, endoplasmic reticulum stress, oxidative stress, proliferation and hormone secretion of ovarian granulosa cells were detected. Our findings showed that isorhamnetin suppressed (P < 0.05) ZEA-induced apoptosis by altering mitochondrial membrane potential and apoptosis-related proteins (B-cell lymphoma-2 [Bcl-2], Bcl2-associated x [Bax] and cleaved caspase-3 [C-Casp3]). Changes in intracellular Ca2+ levels and C/EBP homologous protein (CHOP), recombinant activating transcription factor 6 (ATF6), glucose regulated protein78 kD (GRP78) indicated that isorhamnetin rescued (P < 0.05) ZEA-induced endoplasmic reticulum stress. Furthermore, isorhamnetin prevented (P < 0.05) ZEA-induced oxidative stress via the mitogen-activated protein kinase (P38) signaling pathway. Mechanistically, isorhamnetin stimulated (P < 0.05) the expression of proliferating cell nuclear antigen (PCNA) and cyclin D, thereby increasing the ratio of S phase cells in response to ZEA-induced apoptosis via phosphatidylinositol 3 kinase/protein kinase B (PI3K/Akt) signaling pathway. Isorhamnetin also recovered (P < 0.05) ZEA-induced steroidogenesis disorder by regulating steroidogenic enzyme gene and proteins (follicle-stimulating hormone receptor [FSHR] and cytochrome P450 family 19 subfamily a member 1 [CYP19A1]). Collectively, these findings show that isorhamnetin protects ovarian granulosa cells from ZEA-induced damage, which promotes proliferation, alleviates apoptosis, endoplasmic reticulum stress, oxidative stress, and steroidogenesis disorder.

Metasurface Terahertz Perfect Absorber with Strong Multi-Frequency Selectivity.

In this paper, we design a metasurface terahertz perfect absorber with multi-frequency selectivity and good incident angle compatibility using a double-squared open ring structure. Simulations reveal five selective absorption peaks located at 0-1.2 THz with absorption 94.50% at 0.366 THz, 99.99% at 0.507 THz, 95.65% at 0.836 THz, 98.80% at 0.996 THz, and 86.70% at 1.101 THz, caused by two resonant absorptions within the fundamental unit (fundamental mode of resonance absorption, FRA) and its adjacent unit (supermodel of resonance absorption, SRA) in the structure, respectively, when the electric field of the electromagnetic wave is incident perpendicular to the opening. The strong frequency selectivity at 0.836 THz with a Q-factor of 167.20 and 0.996 THz with a Q-factor of 166.00 is due to the common effect of the FRA and SRA. Then, the effect of polarized electromagnetic wave modes (TE and TM modes) at different angles of incidence (θ) and the size of the open rings on the device performance is analyzed. We find that for the TM mode, the absorption of the resonance peak changes only slightly at θ = 0-80°, which explains this phenomenon. The frequency shift of the absorption peaks caused by the size change of the open rings is described reasonably by an equivalent RLC resonant circuit. Next, by adjusting two-dimensional materials and photosensitive semiconductor materials embedded in the unit structure, the designed metasurface absorber has excellent tunable modulation. The absorption modulation depth (MD) reaches ≈100% using the conductivity of photosensitive semiconductor silicon (σSI-ps), indicating excellent control of the absorption spectrum. Our results can greatly promote the absorption of terahertz waves, absorption spectrum tunability, and frequency selectivity of devices, which are useful in the applications such as resonators, bio-detection, beam-controlled antennas, hyperspectral thermal imaging systems, and sensors.