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OBJECTIVE Two-photon laser-scanning microscopy allows for the monitoring of all brain neurons with single-cell and single-action potential accuracy. This study aimed to investigate the neural responses of the primary auditory cortex to sound stimuli in awake and propofol-anesthetized mice using 2-photon laser-scanning microscopy. METHODS Twelve healthy adult male C57BL/6 mice were used in the present study. In each mouse, the scalp was removed over the entire dorsal skull, and the right primary auditory cortex (A1) located. The test stimulus, used in the awake and propofol-induced anesthetic state, was a group of tones with a random combination of 3 sound intensities and 8 sound frequencies. The calcium indicator GCaMP6s was virally expressed in cortical neurons and neuronal activity was recorded using 2-photon imaging. RESULTS Calcium responses to sound stimuli in two thirds of the neuronal population of the A1 layer were significantly inhibited by propofol anesthesia. In a single neuron, the calcium responses were also inhibited by propofol anesthesia. In the waking state, △F/F (where F is the time series of fluorescence intensity) of all single neurons was significantly higher than that in the propofol-induced anesthetic state (n=669, P

Three new C-geranylated flavonoids named as paucatalinones L (1), M (2), and N (3) were isolated from the seeds of Paulownia catalpifolia T. Gong ex D.Y. Hong. Their structures were determined by means of UV, IR, MS, NMR and CD techniques. Among them, paucatalinone N (3) was the fifth C-geranylflavone derivative obtained from Paulownia genus, and its geranyl variation was firstly displayed in Paulownia C-geranylated flavonoids. Moreover, Compounds 1 and 3 showed good inhibitory effects on xanthine oxidase.

As epoxy resin curing agents, ionic liquids can help improve mechanical properties, flame retardancy, and wear and tear self-healing and extend the pot life of epoxy compositions. The functional de...

Purpose: Here, we examined the role of leukotrienes, well-known inflammatory mediators, in the tumorigenesis of hedgehog pathway-associated medulloblastoma, and tested the efficacies of antagonists of leukotriene biosynthesis in medulloblastoma treatment. Experimental Design: We examined the leukotriene levels in medulloblastoma cells by ELISA. We next tested whether leukotriene synthesis in medulloblastoma cells relied on activation of hedgehog pathway, or the presence of hedgehog ligand secreted by astrocytes. We then investigated whether leukotriene mediated hedgehog-induced Nestin expression in tumor cells. The functions of leukotriene in tumor cell proliferation and tumor growth in medulloblastoma were determined through knocking down 5-lipoxygenase (a critical enzyme for leukotriene synthesis) by shRNAs, or using 5-lipoxygenase–deficient mice. Finally, the efficacies of antagonists of leukotriene synthesis in medulloblastoma treatment were tested in vivo and in vitro. Results: Leukotriene was significantly upregulated in medulloblastoma cells. Increased leukotriene synthesis relied on hedgehog ligand secreted by astrocytes, a major component of medulloblastoma microenvironment. Leukotriene stimulated tumor cells to express Nestin, a cytoskeletal protein essential for medulloblastoma growth. Genetic blockage of leukotriene synthesis dramatically suppressed medulloblastoma cell proliferation and tumor growth in vivo. Pharmaceutical inhibition of leukotriene synthesis markedly repressed medulloblastoma cell proliferation, but had no effect on proliferation of normal neuronal progenitors. Moreover, antagonists of leukotriene synthesis exhibited promising tumor inhibitory efficacies on drug-resistant medulloblastoma. Conclusions: Our findings reveal a novel signaling pathway that is critical for medulloblastoma cell proliferation and tumor progression, and that leukotriene biosynthesis represents a promising therapeutic target for medulloblastoma treatment.

Background: Cytomegalovirus retinitis (CMVR) is a crucial blind-causing disease of AIDS-related ocular opportunistic infection. The CMVR lesions produced retinal necrosis. It is not entirely clear whether CMVR eyes without macular-involved necrotic lesions may have subtle macular damage. In this study, we conducted a cross-sectional study using optical coherence tomography angiography (OCTA) to evaluate macular microvasculature and structure in eyes with AIDS-related CMVR.Methods: Acquired immune deficiency syndrome (AIDS)-related CMVR patients (active and inactive CMVR) and healthy controls treated in the Department of Ophthalmology, Beijing Youan Hospital, Capital Medical University between August 25, 2019, and October 18, 2019, were recruited. All OCTA parameters, including the foveal avascular zone (FAZ), retinal vessel density (VD), choroidal vascularity index (CVI), retinal thickness, and choroidal thickness, were compared between groups after the signal strength was corrected.Results: Signal strength in the 3 × 3 and 6 × 6 mm scan patterns was significantly weaker in the inactive CMVR group than in the control group (both p < 0.001). After adjusting for signal strength, heterogeneity in the central fovea and parafoveal quadrants was present with a shift toward lower macular chorioretinal vasculature, decreased full choroidal thickness, and thicker retinal thickness in the active and inactive CMVR groups. The retinal nerve fiber layer (RNFL) and inner nuclear layer (INL) were significantly thicker in the active and inactive CMVR groups than in the control group (all p < 0.05). For photoreceptor-retinal pigment epithelium (PR-RPE) thickness, no significant differences were found in any quadrant between groups. Foveal avascular zone areas were not significantly different among the three groups (p = 0.053).Conclusions: Subtle macular structure and microvasculature damage still existed in CMVR eyes without macular-involved necrotic lesions. The results of our study are helpful for a deep understanding of the damage caused by CMVR.

BackgroundSystemic lupus erythematosus (SLE) is an autoimmune disease that can involve multiple organs or systems. Lupus nephritis (LN) is associated with high mortality and morbidity. However, plenty of patients do not respond to present treatment or relapse. Iguratimod (IGU) is a new small molecular, anti-rheumatic drug and has shown the potential for drug repurposing from rheumatoid arthritis (RA) to LN treatment. It has been approved for treating RA in northeast Asia. Beyond expectation in a recent observational study, over 90% of thirteen refractory LN patients responded to iguratimod monotherapy in 24 weeks, with no steroids dose increasing or any other medication add-on during the entire follow-up.Methods/designThis study is a multi-center, randomized, 52-week parallel positive drug-controlled study. The study was designed as a head-to-head comparison between the iguratimod and present first-line therapy on LN patients. A total of 120 patients (60 patients each group) is in the enrolling plan. All enrolled patients are assigned randomly into trial and control groups. The patients will be selected from six study sites in China and will all have biopsy-proven active lupus nephritis. In the first 24 weeks of the trial, IGU is compared with cyclophosphamide as an induction therapy, and in the second 24 weeks, IGU is compared with azathioprine as a maintenance therapy. The primary outcome is renal remission rate including both complete remission and partial remission at week 52, which will be analyzed using a non-inferiority hypothesis test.DiscussionMost patients diagnosed with SLE will develop LN within 5 years and LN remains a major cause of morbidity and death for SLE patients. Although some medications are proven effective for the treatment of this condition, at least 20–35% LN patients have to suffer from relapse or ineffective treatment and medication intolerance is also frequent. This trial is designed to demonstrate whether iguratimod can be used as an alternative induction or maintenance therapy in subjects who have lupus nephritis. Data from this study will provide an evidence on whether or not iguratimod should be recommended to active LN patients.Trial registrationClinicalTrials.govNCT 02936375. Registered on October 18, 2016.

Background The aim of the present study was to evaluate the clinical efficacy of laser therapy in the prevention of retinal detachment in patients with acquired immunodeficiency syndrome (AIDS) and cytomegalovirus retinitis (CMVR). Methods A total of 96 eyes from 80 patients with AIDS and CMVR who received anticytomegalovirus (anti-CMV) treatment in the ophthalmology and infection centers of Beijing YouAn Hospital, between June 2016 and August 2018 were retrospectively investigated. The patients were randomly divided into a nonlaser group (50 eyes from 43 patients), who were treated with anti-CMV therapy, and a laser group (46 eyes from 37 patients), who were treated with a fundus laser method to close the retinopathy area after commencing the maintenance stage of anti-CMV treatment. Both groups were followed up for 24 months. The safety of laser therapy was observed, and the efficacy of the therapy was determined by evaluating the incidence of retinal detachment. Results The percentage of retinal detachment in the nonlaser group was 24% compared with 6.5% in the laser group (P=0.018). There was no significant difference between the two groups in the number of CD4+ T cells, the load of human immunodeficiency virus, or the time between the detachment and the end of the induction period. After laser therapy, 39.13% of patients exhibited keratic precipitates (KP), 30.43% had anterior chamber flare (±), 50% had anterior chamber flare (+), and 19.57% had anterior chamber flare (++). Intraocular pressure (IOP) increased in 3 eyes within 2 weeks of laser therapy. The retinal pigment reaction was not obvious in 8 eyes. Conclusions The use of laser therapy in the main maintenance period of anti-CMV treatment can effectively reduce the incidence of retinal detachment in patients with AIDS and CMVR, and the therapy is safe and reliable.

The coxsackievirus A16 (CVA16) is a highly contagious virus that causes the hand, foot, and mouth disease, which seriously threatens the health of children. At present, there are still no available antiviral drugs or effective treatments against the infection of CVA16, and thus it is of great significance to develop anti-CVA16 vaccines. However, the intrinsic uncoating property of the capsid may destroy the neutralizing epitopes and influence its immunogenicity, which hinders the vaccine developments. In the present work, the functional-quantity-based elastic network model analysis method developed by our group was extended to combine with group theory to investigate the uncoating motions of the CVA16 capsid, and then the functionally key residues controlling the uncoating motions were identified by our functional-quantity-based perturbation method. Several motion modes encoded in the topological structure of the capsid were revealed to be responsible for the uncoating of CVA16 particle. These modes predominantly contribute to the fluctuation of the gyration radius of the capsid. Then, by using the perturbation method, four clusters of key sites involved in the uncoating motions were identified, whose perturbations induce significant changes in the fluctuation of the gyration radius. These key residues are mainly located at the 2-fold channels, the quasi 3-fold channels, the bottom of the canyons, and the inter-subunit interfaces around the 3-fold axes. Our studies are helpful for better understanding the uncoating mechanism of the CVA16 capsid and provide potential target sites to prevent the uncoating motions, which is valuable for the vaccine design against CVA16.

Mitochondrial dysfunction is one of the early pathological features of Alzheimer's disease (AD). Accumulation of cerebral and mitochondrial Aβ links to mitochondrial and synaptic toxicity. We have previously demonstrated the mechanism by which presequence peptidase (PITRM1)‐mediated clearance of mitochondrial Aβ contributes to mitochondrial and cerebral amyloid pathology and mitochondrial and synaptic stress in adult transgenic AD mice overexpressing Aβ up to 12 months old. Here, we investigate the effect of PITRM1 in an advanced age AD mouse model (up to 19–24 months) to address the fundamental unexplored question of whether restoration/gain of PITRM1 function protects against mitochondrial and synaptic dysfunction associated with Aβ accumulation and whether this protection is maintained even at later ages featuring profound amyloid pathology and synaptic failure. Using newly developed aged PITRM1/Aβ‐producing AD mice, we first uncovered reduction in PITRM1 expression in AD‐affected cortex of AD mice at 19–24 months of age. Increasing neuronal PITRM1 activity/expression re‐established mitochondrial respiration, suppressed reactive oxygen species, improved synaptic function, and reduced loss of synapses even at advanced ages (up to 19–24 months). Notably, loss of PITRM1 proteolytic activity resulted in Aβ accumulation and failure to rescue mitochondrial and synaptic function, suggesting that PITRM1 activity is required for the degradation and clearance of mitochondrial Aβ and Aβ deposition. These data indicate that augmenting PITRM1 function results in persistent life‐long protection against Aβ toxicity in an AD mouse model. Therefore, augmenting PITRM1 function may enhance Aβ clearance in mitochondria, thereby maintaining mitochondrial integrity and ultimately slowing the progression of AD., Restoration/gain of neuronal PITRM1 function by enhancing its proteolytic activity in the aged AD mouse model significantly promotes synaptic mitochondrial and cerebral Aβ degradation and clearance, and thereby improves mitochondrial and synaptic functions, and alleviates loss of synapses.

Lymph-node (LN) stromal cell populations expand during the inflammation that accompanies T cell activation. Interleukin-17 (IL-17)-producing helper T cells (TH17 cells) promote inflammation through the induction of cytokines and chemokines in peripheral tissues. We demonstrate a critical requirement for IL-17 in the proliferation of LN and splenic stromal cells, particularly fibroblastic reticular cells (FRCs), during experimental autoimmune encephalomyelitis and colitis. Without signaling via the IL-17 receptor, activated FRCs underwent cell cycle arrest and apoptosis, accompanied by signs of nutrient stress in vivo. IL-17 signaling in FRCs was not required for the development of TH17 cells, but failed FRC proliferation impaired germinal center formation and antigen-specific antibody production. Induction of the transcriptional co-activator IκBζ via IL-17 signaling mediated increased glucose uptake and expression of the gene Cpt1a, encoding CPT1A, a rate-limiting enzyme of mitochondrial fatty acid oxidation. Hence, IL-17 produced by locally differentiating TH17 cells is an important driver of the activation of inflamed LN stromal cells, through metabolic reprogramming required to support proliferation and survival. Fibroblastic reticular cells support lymph-node function and adaptive immunity. McGeachy and colleagues show that the cytokine IL-17 is needed to trigger metabolic changes required for the proliferation and survival of these cells in reactive lymph nodes.

In this work, we prepared graphene oxide (GO)-decorated silver-coated gold nanobones (AuNBs@Ag@GO) for obtaining optimal surface-enhanced Raman scattering (SERS) activity. 4-Mercaptobenzoic acid (4-MBA) was adsorbed on the interface between gold and silver to provide more space for GO decoration on the outer surface of silver. Silver was deposited on the middle and end surfaces of the gold nanobones (AuNBs) with negative curvature, which resulted in stubby bimetallic nanocuboids inducing transverse surface plasmon resonance (SPR); the intermediate SPR merged into a new plasmon resonance. The SERS activity of silver-coated gold nanobones (AuNBs@Ag) changed non-monotonically with an increase in the silver coating, which reached up to 8 times larger than that of bare AuNBs. This is better performance than that of silver-coated gold nanorods (AuNRs@Ag). GO hybridized with AuNBs@Ag by electrostatic adherence could further improve the SERS activity of AuNBs@Ag, and the concentration of GO was adjusted for the best SERS performance, which was 4 times higher than that of naked AuNBs@Ag. AuNBs@Ag@GO can be used as a SERS substrate to detect glucose in urine. The mechanism is that the higher concentration of liquid glucose induced a large density of coverage, forming a glucose partition layer on the AuNBs@Ag@GO substrate: with an increase in the glucose concentration, the thickness of the glucose partition layer increased. This reduced the intensity of incident light and resulted in a decrease in the Raman signal of 4-MBA. Moreover, the strong SERS activity of the AuNBs@Ag@GO substrate can provide a wider space to achieve a lower limit of detection (LOD) value for glucose. The intensity of the characteristic Raman peak at 1585 cm−1 linearly decreased with an increase in the glucose concentration in the range of 10–107 nmol L−1 with a low LOD value (S/N = 3) of 2.61 nmol L−1. At the same time, it is confirmed that the SERS substrate can be selective and reliable and shows promising potential and broad applications in glucose detection.

Herein, we demonstrate the successful preparation of a novel complex transition metal oxide (TiVO3.5) by oxidizing a solid-solution MXene (Ti0.5V0.5)3C2 at 300 °C and its high activity as a catalyst precursor in the hydrogen storage reaction of MgH2. The prepared TiVO3.5 inherits the layered morphology of its MXene precursor, but the layer surface becomes very coarse because of the presence of numerous nanoparticles. Adding a minor amount of TiVO3.5 remarkably reduces the dehydrogenation and hydrogenation temperatures of MgH2 and enhances the reaction kinetics. The 10 wt% TiVO3.5-containing sample exhibits optimal hydrogen storage properties, as it desorbs approximately 5.0 wt% H2 in 10 min at 250 °C and re-absorbs 3.9 wt% H2 in 5 s at 100 °C and under 50 bar of hydrogen pressure. The apparent activation energy is calculated to be approximately 62.4 kJ/mol for the MgH2-10 wt% TiVO3.5 sample, representing a 59% reduction in comparison with pristine MgH2 (153.8 kJ/mol), which reasonably explains the remarkably reduced dehydrogenation operating temperature. Metallic Ti and V are detected after ball milling with MgH2; they are uniformly dispersed on the MgH2 matrix and act as actual catalytic species for the improvement of the hydrogen storage properties of MgH2.

In a previous study, we showed that endogenous hydrogen sulfide (H2S) plays a key role in the maintenance of intact adrenal cortex function via the protection of mitochondrial function during endoxemia. We further investigated whether mitochondria-mediated apoptosis is involved in H2S protection of adrenal function. LPS treatment resulted in mitochondria-mediated apoptosis in the adrenal glands of male mice, and these effects were prevented by the H2S donor GYY4137. In the model of Y1 cells, the LPS-induced mitochondria-mediated apoptosis and blunt response to ACTH were rescued by GYY4137. The H2S-generating enzyme cystathionine-β-synthase (CBS) knockout heterozygous (CBS+/-) mice showed mitochondria-mediated apoptosis in the adrenal gland and adrenal insufficiency. GYY4137 treatment restored adrenal function and eliminated mitochondria-mediated apoptosis. Maleimide assay combined with mass spectrometry analysis showed that a number of proteins in mitochondria were S-sulfhydrated in the adrenal gland. ATP5A1 was further confirmed as S-sulfhydrated using a modified biotin switch assay. The level of S-sulfhydrated ATP5A1 was decreased in the adrenal gland of endotoxemic and CBS+/- mice, which was restored by GYY4137. ATP5A1 was identified as sulfhydrated at cysteine 244 by H2S. Overexpression of the cysteine 244 mutant ATP5A1 in Y1 cells resulted in a loss of LPS-induced mitochondria-mediated apoptosis and GYY4137 restoration of LPS-induced hyporesponsiveness to ACTH. Collectively, the present study revealed that decreased H2S generation leads to mitochondrial-mediated apoptosis in the adrenal cortex and a blunt response to ACTH. S-sulfhydration of ATP5A1 at cysteine 244 is an important molecular mechanism by which H2S maintains mitochondrial function and steroidogenesis in the adrenal glands.

Imaging probes targeting type 2 cannabinoid receptor (CB2R) overexpressed in pancreatic duct adenocarcinoma (PDAC) tissue have the potential to improve early detection and surgical outcome of PDAC. The aim of our study was to evaluate the molecular imaging potential of a CB2R-targeted near-infrared (NIR) fluorescent probe (NIR760-XLP6) for PDAC. CB2R overexpression was observed in both PDAC patient tissues and various pancreatic cancer cell lines. In vitro fluorescence imaging indicated specific binding of NIR760-XLP6 to CB2R in human PDAC PANC-1 cells. In a xenograft mouse tumor model, NIR760-XLP6 showed remarkable 50- (ex vivo) and 3.2-fold (in vivo) tumor to normal contrast enhancement with minimal liver and kidney uptake. In a PDAC lymph node metastasis model, significant signal contrast was observed in bilateral axillary lymph nodes with PDAC metastasis after injection of the probe. In conclusion, NIR760-XLP6 exhibits promising characteristics for imaging PDAC, and CB2R appears to be an attractive target for PDAC imaging.

Background This study intends to investigate the immunological effects of tumor ablation with irreversible electroporation (IRE). Methods We evaluated the systemic immune response in patients with hepatocellular carcinoma (HCC) after IRE treatment. Furthermore, we analyzed the tumor infiltrating T lymphocytes and the level of serum cytokines in IRE and control groups of tumor-bearing mice. Results We observed that IRE induced an increase in WBC, neutrophil and monocyte counts and a decrease in lymphocyte count 1 day post-IRE and returned to baseline values within 7 days in the patients. Meanwhile, circulating CD4+ T cell subsets, but not CD8+, decreased 1 day post-IRE. The activated T cells and natural killer (NK) cells increased, and regulatory T (Treg) cells decreased. Furthermore, a significant increase in cytotoxic CD8+ T cells infiltration was observed on ablative tumors in mice. The level of serum IFN-γ also significantly increased in the IRE group. Conclusions Our study demonstrated that IRE not only induced immediate innate immune response dominated by the increase of neutrophils, monocytes and NK cells, but also upregulated activated T cells and downregulated Treg. Meanwhile, the results from the animal model indicated that IRE could induce antitumor adaptive immunity dominated by cytotoxic CD8+ T cells.

Aims Bortezomib (BTZ) is described as the first-line agent for multiple myeloma (MM) chemotherapy, but the emergence of BTZ resistance usually results in the failure of chemotherapy in MM. Circular RNA (circRNA) itchy E3 ubiquitin protein ligase (circITCH) is a novel identified circRNA that plays a vital role in the development of human cancers. However, the role of circITCH in the development of BTZ resistance in MM remains elusive. Materials and methods The expression of circITCH, miR-615-3p, and protein kinase C, delta (PRKCD) was detected with quantitative reverse transcription PCR and western blot. The effects of circITCH on the sensitivity of MM cells to BTZ were assessed using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, flow cytometry, and xenograft tumor assay. The interaction of circITCH, microRNA-615-3p, and PRKCD was explored using luciferase reporter assay and RNA immunoprecipitation assay. Key findings circITCH was downregulated in MM bone marrow specimens and cell lines, as well as BTZ-resistant MM cells. Reduced expression of circITCH was indicative of poor prognosis in MM patients. Upregulation of circITCH enhanced the sensitivity of BTZ-resistant MM cells to BTZ in vitro and in vivo. Furthermore, circITCH was identified as a sponge for miR-615-3p, and PRKCD is confirmed as a direct target of miR-615-3p. Besides, circITCH overexpression enhanced the sensitivity of MM cells to BTZ through miR-615-3p/PRKCD axis. Significance circITCH overexpression enhanced the sensitivity of MM cells to BTZ through miR-615-3p/PRKCD axis, providing a novel potential target for combating BTZ resistance in patients with MM.

Circular RNAs (circRNAs) has been shown to play an important role in the progression of various cancers. However, the function and underlying mechanisms of circRNAs affecting chemotherapy resistance in esophageal squamous cell carcinoma (ESCC) remain largely unknown. In this study, we used gefitinib-resistant (GR) ESCC cells to investigate the function of circPSMC3 and clarify the underlying mechanism in chemotherapy resistance in ESCC. The results suggested that circPSMC3 expression was downregulated, but miR-10a-5p was upregulated in ESCC tissues and cells, as well as in GR ESCC cells. CircPSMC3 overexpression increased the sensitivity of ESCC cells to gefitinib, as indicated by reduced half maximal inhibitory concentration value, increased apoptosis rate and cleaved caspase-3 protein expression. CircPSMC3 directly interacted with miR-10a-5p and inhibited the expression of miR-10a-5p. Phosphatase and tensin homolog (PTEN) was a direct target of miR-10a-5p and circPSMC3 promoted PTEN expression via decreasing miR-10a-5p level. Moreover, the effect of circPSMC3 on resistance of GR ESCC cells to gefitinib was remarkably reduced by restoration of miR-10a-5p and downregultion of PTEN. Taken together, these observations suggested that upregulation of circPSMC3 overcame resistance of GR ESCC cells to gefitinib by modulating the miR-10a-5p/PTEN axis, which provide a new therapeutic strategy for overcoming gefitinib resistance in ESCC.

Phosphatidylinositol 3-kinase alpha (PI3Kα) is among the most important PI3K isoforms and has been associated with multiple human cancers. Therefore, PI3Kα has garnered considerable attention as a viable target for anticancer drug discovery, and thus the identification and development of highly potent inhibitors of this isoform has become an important line of research. Here, structure-based virtual screening, bioassays, and molecular dynamics simulations were performed to discover novel potential PI3Kα inhibitors. TCM-N1 (ZINC13382850) was identified as a possible PI3Kα inhibitor. Particularly, fluorescence quenching assays determined that the binding affinity of the aforementioned compound was superior to that of a reference ligand (BYL719; i.e. a known PI3Kα inhibitor). Moreover, enzymatic activity and cell proliferation inhibition assays indicated that TCM-N1 possessed a moderate inhibition activity against PI3Kα and a relatively high anti-tumor proliferation ability in gastric, colorectal, and cervical cancer cells. The binding model and related thermodynamic parameters further demonstrated that TCM-N1 was tightly embedded into the ATP-binding pocket via hydrogen bonds, van der Waals interactions, and hydrophobic interactions. Therefore, this study provides promising insights into the development and design of more potent PI3Kα-inhibiting analogs. Communicated by Ramaswamy H. Sarma.

Objectives Iguratimod, a novel immunomodulatory agent for rheumatoid arthritis, has been shown to be effective against murine lupus. The aim of this study was to make a preliminary evaluation of the efficacy and safety of iguratimod as salvage therapy in patients with refractory lupus nephritis (LN). Methods We enrolled eligible patients with refractory LN, which we defined as having failed or relapsed on at least two immunosuppressant agents. After enrollment, we substituted iguratimod (25 mg twice daily) for their previous immunosuppressant agents without increasing the dose of steroids. The primary outcome was complete/partial remission (PR/CR) at week 24. Patients who achieved remission continued iguratimod as maintenance therapy over an extended follow-up. Results The study cohort comprised 14 patients with refractory LN, 10 of whom had recent treatment failure and 4 repeated relapses with inadequate initial responses. At enrollment, none of the patients had detectable evidence of extra-renal involvement. The median prednisone dosage was 10 mg/d (IQR 0–10 mg/day). Thirteen patients were eligible for response evaluation, with one patient missed. The renal response rate was 92.3% (12/13) at week 24, with 38.5% (5/13) achieving CR and 53.8% (7/13) achieving PR. We then continued to follow up the responding patients for up to 144 weeks. Twenty-five percent of the patients (3/12) had renal relapse after initial PR. The estimated glomerular filtration rate of all patients maintained stable during follow-up. One patient had a severe adverse reaction (anemia) but recovered fully after stopping iguratimod. Conclusions Our study supports the potential of iguratimod for treatment of refractory LN. Iguratimod could be a promising candidate drug for this condition.

Altered mitochondrial fitness is a potential triggering factor in Alzheimer’s disease (AD). Mitochondrial quality control pathways are dysfunctional and mitochondrially-derived reactive oxygen species (mROS) levels are increased in AD patient brains. However, the pathways responsible for dysregulated mROS accumulation have remained relatively unclear. In this study, we demonstrate that levels of ECSIT, a mitochondrial oxidative phosphorylation (OxPhos) complex I (CI)-associated protein, are reduced in AD-affected brains. Neuronal ECSIT downregulation increased mROS generation and impaired mitophagy of defective mitochondria. Consequently, decreasing neuronal ECSIT caused AD-like changes, including memory loss and neuropathology. In contrast, augmented neuronal expression of ECSIT protected against the development of an AD-like phenotype. Decreased levels of ECSIT in AD patient brains therefore likely contribute to oxidative stress, neuroinflammation and AD pathogenesis.

Carbon-supported nanocrystalline TiO2 (TiO2@C) shows good catalytic activity in the hydrogen storage reaction of MgH2. Adding a small amount of carbon-supported nanocrystalline TiO2 remarkably reduces the dehydrogenation operating temperatures because the MgH2-10 wt% TiO2@C sample starts releasing H2 at 205 °C, which is 95 °C lower than that of pristine MgH2. At 300 °C, the 10 wt% TiO2@C-containing sample rapidly releases 6.5 wt% hydrogen within 7 min. More importantly, the dehydrogenated 10 wt% TiO2@C-containing sample takes up hydrogen even at room temperature and under a hydrogen pressure of 50 bar, and approximately 6.6 wt% hydrogen is absorbed within 10 min at 140 °C. Kinetic measurements reveal a 30% and 50% reduction in the apparent activation energy of the dehydrogenation and hydrogenation of MgH2, respectively, with the presence of 10 wt% TiO2@C additive. Density functional theory calculations present the extended bond lengths and the reduced bond strengths for Mg-H bonding when MgH2 adsorbs on the TiO2 clusters, which is responsible for the reduced de-/hydrogenation temperatures of the TiO2@C-containing MgH2.

Histone deacetylases (HDACs) play a significant role in the epigenetic mechanism by catalyzing deacetylation of lysine on histone in both animals and plants. HDACs involved in growth, development and response to stresses in plants. Arabidopsis thaliana histone deacetylase 14 (AtHDA14) is found to localize in the mitochondria and chloroplasts, and it involved in photosynthesis and melatonin biosynthesis. However, its mechanism of action was still unknowns so far. Therefore, in this study, we constructed AtHDA14 protein model using homology modeling method, validated using PROCHECK and presented using Ramachandran plots. We also performed virtual screening of AtHDA14 by docking with small molecule drugs and predicted their ADMET properties to select representative inhibitors. MD simulation for representative AtHDA14-ligand complexes was carried out to further research and reveal their stability and inhibition mechanism. Meanwhile, MM/PBSA method was utilized to obtain more valuable information about the residues energy contribution. Moreover, compared with four candidate inhibitors, we also found that compound 645533 and 6918837 might be a more potent AtHDA14 inhibitor than TSA (444732) and SAHA (5311). Therefore, compound 6445533 and 6918837 was anticipated to be a promising drug candidate for inhibition of AtHDA14.

The cooperative mechanism of Ni(0)/Lewis acid catalyzed carbocyanation of alkyne with 2,3,5,6-tetrafluorobenzonitrile was investigated using the DFT method. Our calculations indicate that the most feasible catalytic cycle consists of the oxidative addition of a C–CN bond to the Ni(0) center, alkyne insertion into the C(aryl)–Ni(II) bond, and reductive elimination. Notably, the Lewis acid (LA) interacting with the cyano nitrogen atom of the substrate can have a significant effect on activating the C–CN bond while suppressing C–H and C–F bond activations. The origin of lower C–CN activation barrier in the presence of LA can be attributed to the remarkably enhanced charge transfer (CT) amount from the Nicat 3d orbital to C-CN σ* + π* antibonding molecular orbital and the little decrease of interaction energy between Ni-catalyst and substrate. In the C–F and C–H bond activations in the presence of LA, on the contrary, the significant decrease of interaction energy between Ni-catalyst and substrate and almost ...

A novel dual-cation/anion complex hydride (Li2Mg(BH4)2(NH2)2), which contains a theoretical hydrogen capacity of 12.1 wt%, is successfully synthesized for the first time by ball milling a mixture consisting of MgBH4NH2 and Li2BH4NH2. The prepared Li2Mg(BH4)2(NH2)2 crystallizes in a triclinic structure, and the [NH2] and [BH4] groups remain intact within the structure. Upon heating, the prepared Li2Mg(BH4)2(NH2)2 decomposes to release approximately 8.7 wt% hydrogen in a three-step reaction at 100–450 °C. In addition, a small amount of ammonia is evolved during the first and second thermal decomposition steps as a side product. This ammonia is responsible for the lower experimental dehydrogenation amount compared to the theoretical hydrogen capacity. The XRD and FTIR results reveal that Li2Mg(BH4)2(NH2)2 first decomposes to LiMgBN2, LiBH4, BN, LiH and MgBNH8 at 100–250 °C, and then, the newly formed MgBNH8 reacts with LiH to form Mg, LiBH4 and BN at 250–340 °C. Finally, the decomposition of LiBH4 releases hydrogen and generates LiH and B at 340–450 °C.

Background: To observe the retinal lesions in HIV/AIDS patients and to evaluate the consistency of non-mydriatic ultra-wide-field (UWF) retinal imaging and mydriatic slit lamp biomicroscope with Superfield lens. Methods: 193 eyes of 98 consecutive HIV/AIDS patients were enrolled. The retinal lesions in each patients were observed through UWF fundus imaging and slit lamp biomicroscopic with Superfield lens whose consistency was analyzed. Results: 100 eyes (51.8%） had fundus lesions, 20 eyes (20%) presented posterior microvascular retinopathy (MVR), 19 eyes (19%) presented peripheral MVR, 15 eyes (15%) presented early stage cytomegalovirus retinitis (CMVR), 6 eyes showed initial stage CMVR, and 51 eyes showed other changes (papilledema, etc.). The consistency of two methods was moderate in detecting the isolated peripheral lesions (Kappa = 0.445) or HIV-related MVR (Kappa = 0.513), and high in inspecting the posterior/posterior involved lesions (Kappa = 0.831) or CMVR (Kappa = 1.0). The detection rate of UWF retinal imaging and slit lamp biomicroscopic were 15.5%（30/193）and 17.6%（34/193）(P=0.557＞0.05) for HIV-related MVR, 7.8% (15/193) (P=1.000＞0.05) for CMVR, 37.3% (72/193) and 33.7% (65/193) (P=0.118＞0.05) for posterior/posterior involved lesions, 8.8% (17/193) and 17.6% (34/193) (P=0.001＜0.05) for isolated peripheral lesions , respectively. Conclusions: The HIV-related MVR can be posterior or peripheral. Various fundus changes appear in HIV/AIDS patients, not only MVR or CMVR. The non-mydriatic UWF fundus imaging system and mydriatic slit lamp biomicroscope exhibited good consistency and nondiscriminatory detection rate for CMVR, HIV-related MVR and posterior lesions, but not for isolated peripheral lesions.

The cultivation of Pleurotus eryngii is increasing rapidly in China due to its nutritional and medicinal importance, excellent flavor, and long shelf life; therefore, cheaper and locally available alternative substrates are urgently needed. Experiments were performed to investigate the use of alternative substrates for P. eryngii cultivation. Korshinsk peashrub (Caragana korshinskii Kom.), a perennial shrub, was included in the substrate at varying rates to substitute for the sawdust and sugarcane bagasse (21/38 and 21/35%, respectively) in the typical substrate. The cultivation substrate including 38% Korshinsk peashrub did not significantly affect linear mycelial growth. The fruit body yield (247.3 g/bag) and biological efficiency (70.66%) achieved by using this substrate were significantly higher than those achieved using the control substrate (229.6 g/bag and 65.59%). Crude polysaccharide content was highest (6.12%) in the mushroom grown on 38% Korshinsk peashrub substrate; in this mushroom, crude polysaccharide content was increased by 70.47% compared with that of the mushroom grown on the control substrate (3.59%). These results reveal that supplementing the substrate in which P. eryngii is grown with Korshinsk peashrub can improve polysaccharose accumulation by P. eryngii. The findings described above reveal that Korshinsk peashrub is an efficient, cost-effective, and promising substrate additive that can improve P. eryngii quality and yield while largely substituting for sawdust and sugarcane bagasse.

Internal oxidative stress can trigger microsclerotia (MS) formation of Metarhizium rileyi in liquid culture. Activator protein 1 (AP1) is a transcription factor and an important determinant of the response to oxidative stress. To investigate how M. rileyi responds to internal oxidative stress and how MS development is regulated, the Mrap1 gene was characterized. Mrap1 was highly expressed during periods of invasive hyphal growth and in response to changing culture conditions during MS development. Compared with the wild-type and complemented strains, ΔMrap1 mutants exhibited various defects in aerial hyphal growth, yeast-to-hypha transition, and conidia and MS formation. ΔMrap1 mutants also displayed sensitivity to oxidative stress, were morphologically abnormal, and responded differently to oxidative stress during MS development. ΔMrap1 mutants had significantly reduced conidial (74-82%) and MS (99%) yields. Insect bioassays revealed that ΔMrap1 mutants displayed reduced virulence in topical (43-76%) and injection (45-70%) bioassays. Moreover, the ability of ΔMrap1 mutants to grow out of the cuticle was reduced due to impaired conidiation on the host cadaver. Digital gene expression profiling revealed that genes involved in antioxidation, pigment biosynthesis, and ion transport were regulated by Mrap1 during MS development. Taken together, our results confirm the importance of Mrap1 in vegetative growth, conidia and MS formation, and virulence.

A modified ReaxFF force field was used to study dynamic deformation of Al nanoparticles (ANPs) and chemical evolution of RDX/Al mixtures. When small ANPs impact RDX crystal planes, the interaction between RDX and Al at the initial stage does not affect the order of shock-induced anisotropic response of RDX crystal and different thickness of alumina shell on ANPs exhibits different capacity to resist structural deformation. When Al slab with 30 wt% is coated with a 3 nm thickness of alumina, Al slab exhibits inert characteristics and provides high compression condition to enhance decomposition of RDX molecules during the initial impact stage.

Magnesium hydride (MgH2) has attracted intense interest as a high-capacity hydrogen storage material. However, high thermal stability and slow kinetics limit its practical applications. Herein, vanadium oxide nanoparticles supported on cubic carbon nanoboxes (nano-V2O3@C) are synthesized successfully by using MIL-47(V) as a precursor, and superior catalytic effects derived from the nano-V2O3@C composite towards the hydrogen storage reaction of MgH2 are demonstrated. The MgH2-9 wt% nano-V2O3@C sample starts releasing hydrogen at 215 °C, which is 60 °C lower than that of the additive-free MgH2. At 275 °C, approximately 6.4 wt% of hydrogen is released from the MgH2-9 wt% V2O3@C sample within 20 min. The dehydrogenated sample absorbs hydrogen even at room temperature under 50 bar of hydrogen pressure, and rehydrogenation is complete within 700 s at 150 °C. XRD and XPS measurements identify the existence of metallic V after ball milling, and its presence remains nearly constant in the subsequent dehydrogenation/hydrogenation process upon heating. Further ab initio calculations reveal that the presence of V facilitates the breaking of the Mg–H bond of the MgH2 unit, which is reasonably responsible for the significantly reduced operating temperatures and improved kinetics of the V-catalysed MgH2.

CP43 is closely associated with the photosystem II and exists the plant thylakoid membranes. The acidic pH-induced structural changes had been investigated by fluorescence spectrum, ANS spectrum, RLS spectrum, energy transfer experiment, acrylamide fluorescence quenching assay and MD simulation. The fluorescence spectrum indicated that the structural changes in acidic pH-induced process were a four-state model, which was nature state (N), partial unfolding state (PU), refolding state (R), and molten-globule state (M), respectively. Analysis of ANS spectrum illustrated that inner hydrophobic core exposed partially to surface below pH 2.0 and inferred also that the molten-globule state existed. The RLS spectrum showed the aggregation of apo-CP43 around the pI (pH 4.5–4.0). The alterations of apo-CP43 secondary structure with different acidic treatments were confirmed by FTIR spectrum. The energy transfer experiment and quenching research demonstrated structural change at pH 4.0 was loosest. The RMSF suggested two terminals played an important function in acidic denaturation process. The distance of two terminals shown slight difference in acidic pH-induced process during the unfolding process, both N-terminal and C-terminal occupied the dominant role. However, the N-terminal accounted for the main part in the refolding process. All kinds of SASA values corresponded to spectral results. The tertiary and secondary structure by MD simulation indicated that the part transmembrane α-helix was destroyed at low pH.

Background: Staphylococcus aureus is a leading cause of contagious mastitis in dairy cattle. Internalization of S. aureus by bovine mammary gland epithelial cells is thought to be responsible for persistent and chronic intramammary infection, but the underlying mechanisms are not fully understood. Methods: In the present study, we evaluated the role of Annexin A2 (AnxA2), a membrane-binding protein, in S. aureus invasion into bovine mammary epithelial cell line (MAC-T). In vitro binding assays were performed to co-immunoprecipitate the binding proteins of AnxA2 in the lysates of S. aureus. Results: AnxA2 mediated the internalization but not adherence of S. aureus. Engagement of AnxA2 stimulated an integrin-linked protein kinase (ILK)/p38 MAPK cascade to induce S. aureus invasion. One of the AnxA2-precipitated proteins was identified as S. aureus clumping factor B (ClfB) through use of mass spectrometry. Direct binding of ClfB to AnxA2 was further confirmed by using a pull-down assay. Pre-incubation with recombinant ClfB protein enhanced S. aureus internalization, an effect that was specially blocked by anti-AnxA2 antibody. Conclusion: Our results demonstrate that binding of ClfB to AnxA2 has a function in promoting S. aureus internalization. Targeting the interaction of ClfB and AnxA2 may confer protection against S. aureus mastitis.

The highly selective nickel(0)-catalyzed cyanoesterification of cyanoformates with alkynes is greatly facilitated by Lewis acid (LA). We report density functional theory (DFT) investigations on the mechanistic details and provide a rational explanation of the “LA effect”. Our calculations disclose that an unusual biphosphine cycle including rate-determining oxidative addition of a C–CN bond, alkyne migratory insertion, and reductive elimination steps is more favorable than the generally accepted monophosphine cycle. The LA has a non-negligible impact on the mechanistic origin of selective C–CN bond activation. Furthermore, the presence of LA dramatically accelerates alkyne migratory insertion because the strong electron-withdrawing property of LA strengthens the coordination ability of the Ni center with alkyne to form the thermodynamically favorable five-coordinate nickel(II) cyanide carboxylate species, which then avoids the large deformation of the transition state of alkyne migration insertion to give...

Background Anisodamine is used for the treatment of reperfusion injury in various organs. In this study, we investigated the effectiveness and mechanisms of action of anisodamine in promoting recovery from glycerol-induced acute kidney injury (AKI). Methods We compared the protective effects of atropine and anisodamine in the rat model of glycerol-induced AKI. We examined signaling pathways involved in oxidative stress, inflammation and apoptosis, as well as expression of kidney injury molecule-1 (KIM-1). Renal injury was assessed by measuring serum creatinine and urea, and by histologic analysis. Rhabdomyolysis was evaluated by measuring creatine kinase levels, and oxidative stress was assessed by measuring malondialdehyde (MDA) and superoxide dismutase (SOD) levels in kidney tissues. Inflammation was assessed by quantifying interleukin 6 (IL-6) and CD45 expression. Apoptosis and necrosis were evaluated by measuring caspase-3 (including cleaved caspase 3) and RIP3 levels, respectively. Results Glycerol administration resulted in a higher mean histologic damage score, as well as increases in serum creatinine, urea, creatine kinase, reactive oxygen species (ROS), MDA, IL-6, caspase-3 and KIM-1 levels. Furthermore, glycerol reduced kidney tissue SOD activity. All of these markers were significantly improved by anisodamine and atropine. However, the mean histologic damage score and levels of urea, serum creatinine, creatine kinase, ROS and IL-6 were lower in the anisodamine treatment group compared with the atropine treatment group. Conclusion Pretreatment with anisodamine ameliorates renal dysfunction in the rat model of glycerol-induced rhabdomyolytic kidney injury by reducing oxidative stress, the inflammatory response and cell death.

Pin1, a polypeptide proline isomerase parvulin, plays a key role in Alzheimer’s disease (AD), common tumors and cancers. Two conservative histidine residues, His59 and His157, are important for maintaining the stability of the PPIase domain. Hence multiple spectral and computational techniques were performed to investigate the potential mechanism of two histidine residues. Thermal denaturation indicated that both residues His59 and His157 are not sensitive to the lower temperatures, while residue His59 is more sensitive to the higher temperatures than residue His157. Acidic denaturation suggested that influences of both residues His59 and His157 to acidic stability were the difference from Pin1-WT. ANS and RLS spectra hinted that there was no significant effect on hydrophobic change and aggregation by histidine mutations. The GndHCl-induced denaturation implied that residues His59 and His157 contributed the most to the chemical stability. MD simulations revealed that residues His59 and His157 mutations resulted in that the hydrogen bond network of the dual histidine motif was destroyed wholly. In summary, these histidine residues play an important role in maintaining the structural stability of the PPIase domain.

Polychlorinated biphenyls (PCBs) would do serious damage to multiple systems, while coplanar polychlorinated biphenyls, the most toxic member of the family, has been widely taken into consideration. In this study, ICR mice were fed with different doses of PCB126 to explore the underlying molecular mechanisms on immunotoxicity. The results showed that PCB126 caused immunosuppression as evidenced by inhibiting the ratios of thymus and spleen weights, changing the organizational structure and decreasing levels and mRNA expression of TNF-α, IFN-γ and IL-2. PCB126 inhibited the SOD activity and spurred the accumulation of MDA in spleen and thymus. Meanwhile, it also disturbed the Nrf2 signaling pathway as evidenced by up-regulating the mRNA expression of Nrf2 and Keap1. Additionally, a remarkable reduction in the mRNA expression of AhR and enhancement in the mRNA expression of Cyp1 enzymes (Cyp1a1, Cyp1a2 and Cyp1b1) were observed, which increased the ROS levels. PCB126 could increase protein expression of Bax, Caspase-3, Caspase-8 and Caspase-9, while the protein expression of Bcl-2 was decreased. In summary, the results indicated that PCB126 modulated the AhR signaling pathway, which interacted with apoptosis and oxidative stress to induce immunotoxicity, enrich the immunotoxicological mechanisms of PCB126.

Brexpiprazole which marketed as Rexulti® is a second-generation atypical antipsychotic. A seemingly random and uncontrollable “ghost peak” that vary from below the detection limit to ∼0.2% was observed occasionally during the development of HPLC method for brexpiprazole drug substance. The “ghost peak” was finally characterized as a syn head-to-tail dimer of brexpiprazole by UV, IR, LC–MS/TOF, 1D and 2D NMR. It was formed rapidly through photocatalytic [2 + 2] pericyclic reaction and can reach approximately 1.7% in five minutes once the analytes were exposed to sunlight at noon. By contrast, the occurrence of this “ghost peak” in brexpiprazole can be suppressed when the solutions were prepared and stored away from sunlight.

Lily is a well-known ornamental plant with a diversity of fragrant types. Basic information on lily floral scent compounds has been obtained for only a few accessions, and little is known aboutLiliumaroma types, the terpene synthase genes that may play roles in the production of key volatiles, or the range of monoterpenes that these genes produce. In this study, 41 cultivars were analyzed for volatile emissions, and a total of 46 individual volatile compounds were identified, 16 for the first time in lilies. Lily accessions were classified into six groups according to the composition of major scent components: faint-scented, cool, fruity, musky, fruity-honey, and lily. Monoterpenes were one of the main groups of volatiles identified, and attention was focused on terpene synthase (TPS) genes, which encode enzymes that catalyze the last steps in monoterpene synthesis. Thirty-two candidate monoterpene synthase cDNAs were obtained from 66 lily cultivars, and 64 SNPs were identified. Two InDels were also shown to result from variable splicing, and sequence analysis suggested that different transcripts arose from the same gene. All identified nucleotide substitution sites were highly correlated with the amounts of myrcene emitted, and InDel site 230 was highly correlated with the emission of all major monoterpenoid components, especially (E)-β-ocimene. Heterologous expression of five cDNAs cloned from faint-scented and strong-scented lilies showed that their corresponding enzymes could convert geranyl diphosphate to (E)-β-ocimene,α-pinene, and limonene. The findings from this study provide a major resource for the assessment of lily scent volatiles and will be helpful in breeding of improved volatile components.

PAP80-2a, purified from Pholiota adiposa mycelia, is a polysaccharide exhibiting prominent antitumor effects. However, the yield of PAP80-2a was low and its structure has not been characterized, impeding the exploration of its structure-function relationship, thus influencing the development of oral drugs for antitumor therapy and immunomodulation. In order to improve the yield of PAP80-2a, response surface methodology along with Box-Behnken design was applied to optimize the ultrasonic-assisted extraction conditions for polysaccharides. Then, the structure of PAP80-2a exhibiting antitumor activity was determined from different angles. The results showed that the extraction yield of P. adiposa polysaccharides increased by 11.5% under optimized ultrasonic extraction conditions. Structural analysis showed that PAP80-2a was mainly composed of glucose, rhamnose, xylose, and galactose in a ratio of 10.00: 2.09: 4.09: 1.13. The total amino acid content in the sugar chain was 69.92 μg/mL. The sugar chain structure was [α-Rha (1 → 3)-]n, and rhamnose was located at the non-reducing end of the sugar chain, while glucose was located at the non-reducing end or in the sugar chain in 1,2,6- and 1,3,6-linked forms. Our study clearly illuminates the primary structure of PAP80-2a, but 3D structure of PAP80-2a and its structure–function relationship is a future challenge.

Background This study aimed to explore the molecular mechanism and clinical relevance of iguratimod in the regulation of human B cell terminal differentiation. Methods An in vitro human antibody-secreting cell (ASC) differentiation system was established to test the effect of iguratimod. B cell phenotype and key transcription factors (TFs) relevant to ASC differentiation were analyzed through flow cytometry and qPCR. The COX-2 activity was measured by enzyme immunoassay (EIA). RNA sequencing was used to identify potential targets of iguratimod. We enrolled six treatment-naive rheumatoid arthritis (RA) patients whose blood samples were collected for phenotypic and molecular studies along with 12-week iguratimod monotherapy. Results Iguratimod inhibited human ASC generation without affecting B cell activation and proliferation. Iguratimod showed only weak COX-2 activity. Gene set enrichment analysis (GSEA) identified that protein kinase C (PKC) pathway was targeted by iguratimod which was confirmed by PKC activity detection. Furthermore, early growth response 1 (EGR1), a target of PKC and a non-redundant TF for ASC differentiation, was found to be the most downregulated gene in iguratimod-treated B cells. Lastly, iguratimod monotherapy decreased peripheral ASCs and was associated with improved disease activity. The expression of major ASC-related TFs, including EGR1, was similarly downregulated in patient blood samples. Conclusions Iguratimod inhibits ASC differentiation both in vitro and in RA patients. Our study suggests that PKC/EGR1 axis, rather than COX-2, is critically involved in the inhibitory effect by iguratimod on human ASC differentiation. Iguratimod could have a broader application to treat B cell-related autoimmune diseases in clinics. Electronic supplementary material The online version of this article (10.1186/s13075-019-1874-2) contains supplementary material, which is available to authorized users.

Phytol is the isoprenoid alcohol bound in ester linkage to chlorophyll, the most abundant photosynthetic pigment in plants. During leaf senescence, large amounts of phytol are released by chlorophyll degradation. However, the pathway of phytol catabolism in plants is unknown. We hypothesized that phytol degradation in plants might involve its oxidation into the long-chain aldehyde phytenal. Using GC-MS for aldehyde quantification after derivatization with methylhydroxylamine, phytenal was identified in leaves, whereas other long-chain aldehydes (phytanal and pristanal) were barely detectable. We found that phytenal accumulates during chlorotic stresses, for example, salt stress, dark-induced senescence, and nitrogen deprivation. The increase in the phytenal content is mediated at least in part independently of enzyme activities, and it is independent of light. Characterization of phytenal accumulation in the pao1 mutant affected in chlorophyll degradation revealed that phytenal is an authentic phytol metabolite derived from chlorophyll breakdown. The increase in phytenal was even stronger in mutants affected in the production of other phytol metabolites including vte5-2 (tocopherol deficient) and pes1 pes2 (fatty acid phytyl ester deficient). Therefore, phytenal accumulation is controlled by competing, alternative pathways of phosphorylation (leading to tocopherol production) or esterification (fatty acid phytyl ester production). As a consequence, the content of phytenal is maintained at low levels, presumably to minimize its toxic effects caused by its highly reactive aldehyde group that can form covalent bonds with and inactivate the amino groups of proteins.

In this research, we carried out spectral and computational methods to investigate the influence of galloyl moiety on Pin1. The fluorescence emission spectra revealed that the fluorescence quenching of Pin1 by epigallocatechin-3-gallate (EGCG) was a simultaneous dynamic and static quenching process, whereas the fluorescence quenching of Pin1 by epigallocatechin (EGC) was only a static quenching. In addition, the studies also indicated that the binding sites of EGCG and EGC to Pin1 were 2 and 1, respectively. Thermodynamic parameters, binding models, computational simulations and predicted binding free energy implied that hydrogen bonds, van der Waals and hydrophobic interactions were main binding forces in the Pin1-EGCG and Pin1-EGC systems. The synchronous and three-dimensional fluorescence, circular dichroism and Fourier transform infrared spectra illustrated that both EGCG and EGC could influence the conformation of Pin1. The fluorescence studies suggested that EGCG were bound to both the PPIase and WW domain, while EGC only was bound to the PPIase domain. The phenomena were further described using molecular docking and molecular dynamic simulations. Taken together, this research revealed that the inhibitory effect of EGCG on Pin1 was stronger than that of EGC, which was mainly due to the galloyl moiety.

A simple but effective near-infrared ratiometric fluorescent probe for hydrazine has been developed by a hybrid fluorophore of coumarin and benzopyrylium. The recognition mechanism involving spirocyclic ring-opening and −closing toward hydrazine is first reported. The probe showed high selectivity and sensitivity toward hydrazine with lower detection limit (1.5 ppb) under single wavelength excitation. Upon addition of trace amounts of hydrazine, the probe showed a remarkable ratiometric change in the absorption (Δλ = 167 nm) and emission (Δλ = 201 nm) spectra and a color change from green to yellow. Furthermore, the probe-loaded TLC plates were made to detect vapor of hydrazine by naked eyes. Moreover, this ratiometric probe was successfully used for the imaging of hydrazine in fetal bovine serum and living cells.

Mitochondrial abnormalities are well known to cause cognitive decline. However, the underlying molecular basis of mitochondria-associated neuronal and synaptic dysfunction in the diabetic brain remains unclear. Here, using a mitochondrial single-channel patch clamp and cyclophilin D (CypD)-deficient mice (Ppif −/−) with streptozotocin-induced diabetes, we observed an increase in the probability of Ca2+-induced mitochondrial permeability transition pore (mPTP) opening in brain mitochondria of diabetic mice, which was further confirmed by mitochondrial swelling and cytochrome c release induced by Ca2+ overload. Diabetes-induced elevation of CypD triggers enhancement of F1F0 ATP synthase–CypD interaction, which in turn leads to mPTP opening. Indeed, in patients with diabetes, brain cypD protein levels were increased. Notably, blockade of the F1F0 ATP synthase–CypD interaction by CypD ablation protected against diabetes-induced mPTP opening, ATP synthesis deficits, oxidative stress, and mitochondria dysfunction. Furthermore, the absence of CypD alleviated deficits in synaptic plasticity, learning, and memory in diabetic mice. Thus, blockade of ATP synthase interaction with CypD provides a promising new target for therapeutic intervention in diabetic encephalopathy.