Structure and function of the Arabidopsis ABC transporter ABCB19 in brassinosteroid export.

Brassinosteroids are steroidal phytohormones that regulate plant development and physiology, including adaptation to environmental stresses. Brassinosteroids are synthesized in the cell interior but bind receptors at the cell surface, necessitating a yet to be identified export mechanism. Here, we show that a member of the ATP-binding cassette (ABC) transporter superfamily, ABCB19, functions as a brassinosteroid exporter. We present its structure in both the substrate-unbound and the brassinosteroid-bound states. Bioactive brassinosteroids are potent activators of ABCB19 ATP hydrolysis activity, and transport assays showed that ABCB19 transports brassinosteroids. In Arabidopsis thaliana, ABCB19 and its close homolog, ABCB1, positively regulate brassinosteroid responses. Our results uncover an elusive export mechanism for bioactive brassinosteroids that is tightly coordinated with brassinosteroid signaling.

Effects of straw returning combined with blended controlled-release urea fertilizer on crop yields, greenhouse gas emissions, and net ecosystem economic benefits: A nine-year field trial.

Although straw returning combined with blended controlled-release urea fertilizer (BUFS) has been shown to improve wheat-maize rotation system productivity, their effects on greenhouse gas (GHG) emissions, carbon footprints (CF), and net ecosystem economic benefits (NEEB) are still unknown. Life cycle assessment was used to investigate a long-term (2013-2022) wheat-maize rotation experiment that included straw combined with two N fertilizer types [BUFS and (conventional urea fertilizer) CUFS] and straw-free treatments (BUF and CUF). The results showed that BUFS and CUFS treatments increased the annual yield by 13.8% and 11.5%, respectively, compared to BUF and CUF treatments. The BUFS treatment increased the yearly yield by 13.8% compared to the CUFS treatment. Since BUFS and CUFS treatments increased soil organic carbon (SOC) sink sequestration by 25.0% and 27.0% compared to BUF and CUF treatments, they reduced annual GHG emissions by 7.1% and 4.7% and CF per unit of yield (CFY) by 13.7% and 9.6%, respectively. BUFS treatment also increased SOC sink sequestration by 20.3%, reduced GHG emissions by 10.7% and CFY by 23.0% compared to CUFS treatment. It is worth noting that the BUFS and CUFS treatments increased the annual ecological costs by 41.6%, 26.9%, and health costs by 70.1% and 46.7% compared to the BUF and CUF treatments, but also increased the net yield benefits by 9.8%, 6.8%, and the soil nutrient cycling values by 29.2%, 27.3%, and finally improved the NEEB by 10.1%, 7.3%, respectively. Similar results were obtained for the BUFS treatment compared to the CUFS treatment, ultimately improving the NEEB by 23.1%. Based on assessing yield, GHG emissions, CF, and NEEB indicators, the BUFS treatment is recommended as an ideal agricultural fertilization model to promote sustainable and clean production in the wheat-maize rotation system and to protect the agroecological environment.

Si-Zhi Wan regulates osteoclast autophagy in osteoporosis through the AMPK signaling pathway to attenuate osteoclastogenesis.

OBJECTIVES: The mechanisms underlying the therapeutic effects of Si-Zhi Wan (SZW), a traditional Chinese medicine used to treat osteoporosis (OP), remain unknown. This study investigated the therapeutic effects of SZW on mice that underwent ovariectomy (OVX) and underlying mechanisms thereof. METHODS: We established an in vivo model of OP by performing OVX in mice. Microcomputed tomography (Micro-CT) was used to assess changes in bone characteristics of mice following SZW administration for 4 weeks. H&E staining revealed alterations in bone tissues of mice. Osteoclastogenesis in mouse bone tissue was observed using tartrate-resistant acid phosphatase staining and western blotting. Furthermore, we examined the impact of SZW on osteoclastogenesis in vitro using receptor activator of nuclear factor kappa-B ligand (RANKL). Finally, we explored the regulatory effects of SZW on osteoclast autophagy and the AMPK pathway. KEY FINDINGS: The results demonstrated that high-dose SZW reversed changes in bone density parameters caused by OVX, including bone volume (BV), BV/total volume, trabecular number, and trabecular spacing (P = 0.0007, 0.0035, 0.0114, and 0.0182, respectively), and stimulated the formation of bone trabeculae in mice (P < 0.0001). Furthermore, SZW suppressed osteoclast formation in mice with OVX and inhibited osteoclast formation induced by RANKL. Mechanistically, SZW inhibited osteoclast precursor cell autophagy through the AMPK pathway. CONCLUSIONS: SZW effectively inhibited the autophagy of osteoclast precursors by regulating the AMPK pathway, thereby exerting anti-osteoclastogenic effects and serving as an alternative therapy for OP.

Structural basis for abscisic acid efflux mediated by ABCG25 in Arabidopsis thaliana.

Abscisic acid (ABA) is a phytohormone essential to the regulation of numerous aspects of plant growth and development. The cellular level of ABA is critical to its signalling and is determined by its rate of biosynthesis, catabolism and the rates of ABA transport. ABCG25 in Arabidopsis thaliana has been identified to be an ABA exporter and play roles in regulating stomatal closure and seed germination. However, its ABA transport mechanism remains unknown. Here we report the structures of ABCG25 under different states using cryo-electron microscopy single particle analysis: the apo state and ABA-bound state of the wild-type ABCG25 and the ATP-bound state of the ATPase catalytic mutant. ABCG25 forms a homodimer. ABA binds to a cone-shaped, cytosolic-facing cavity formed in the middle of the transmembrane domains. Key residues in ABA binding are identified and verified by a cell-based ABA transport assay. ATP binding leads to closing of the nucleotide-binding domains of opposing monomers and conformational transitions of the transmembrane domains. Together, these results provide insights into the substrate recognition and transport mechanisms of ABCG25 in Arabidopsis, and facilitate our understanding of the ABA transport and signalling pathway in plants.

Guizhi Shaoyao Zhimu granules attenuate bone destruction in mice with collagen-induced arthritis by promoting mitophagy of osteoclast precursors to inhibit osteoclastogenesis.

BACKGROUND: Guizhi Shaoyao Zhimu decoction, a traditional Chinese medicine formula used empirically for the treatment of rheumatoid arthritis (RA), has been shown to alleviate bone destruction in rats with collagen-induced arthritis (CIA). PURPOSE: The aim of this study is to characterize the effects of Guizhi Shaoyao Zhimu granules (GSZGs) on bone destruction in RA and the underlying mechanism. STUDY DESIGN: A CIA arthritis model using DBA/1 mice. The animals were divided into a normal group; CIA model group; low, medium, and high-dose GSZG groups (3, 6, and 9 g/kg/day); and a methotrexate group (1.14 mg/kg/w). In vitro, a cytokine induced osteoclastogenesis model was established. METHODS: After 28 days of treatment, the paw volume was measured, bone destruction was examined by micro-CT, and the generation of osteoclasts in bone tissue was evaluated via tartrate-resistant acid phosphatase (TRAP) staining. Furthermore, the inhibitory effect and underlying mechanism of action of GSZG on RANKL-induced osteoclastogenesis were investigated in vitro. RESULTS: The in vivo analyses demonstrated that the paw volume and degree of bone erosion of mice in the medium- and high-dose GSZG groups were significantly decreased compared to the CIA model group. In addition, GSZG treatment suppressed the excessive generation of osteoclasts in the bone tissue of CIA mice. In vitro, GSZG inhibited RANKL-induced osteoclastogenesis and osteoclast-mediated bone resorption. Specifically, it only inhibited the generation of osteoclast precursors (OCPs); it had no significant effect on the fusion of OCPs or maturation of osteoclasts. Finally, we showed that the inhibitory effect of GSZG on osteoclastogenesis was related to the promotion of PTEN-induced kinase protein 1 (PINK1)/Parkin pathway-mediated mitophagy of osteoclast precursors, which was verified using a PINK1 knockdown small interfering RNA in OCPs. CONCLUSION: These findings indicate that GSZG is a candidate for the treatment of bone destruction in RA and provide a more detailed elucidation of the mechanism of GSZG anti-RA bone erosion, i.e., inhibition of the ROS/NF-κB axis through the PINK1/Parkin-mediated mitochondrial autophagic pathway to inhibit osteoclast precursor production, compared to the published literature.

Mechanism of action of quercetin in rheumatoid arthritis models: meta-analysis and systematic review of animal studies.

Quercetin, a typical flavonoid derived from a common natural plant, has multiple biological activities. Previous research in animal models has demonstrated the effectiveness of quercetin in treating rheumatoid arthritis (RA). The pharmacological effects and probable mechanisms of quercetin were evaluated in this study. Three databases, PubMed, Web of Science, and Embase, were searched for relevant studies from the creation of the databases to November 2022. Methodological quality was assessed using the SYRCLE risk of bias tool. STATA 15.1 was used to perform the statistical analysis. This research included 17 studies involving 251 animals. The results indicated that quercetin was able to reduce arthritis scores, paw swelling, histopathological scores, interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-17 (IL-17), tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1), C-reactive protein (CRP), malondialdehyde (MDA), reactive oxygen species (ROS), thiobarbituric acid reactive substances (TBARS), nuclear factor kappa B (NF-kB) and increase interleukin-10 (IL-10), catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), glutathione (GSH), and heme oxygenase-1 (HO-1). These may be related to quercetin's potential anti-inflammatory, anti-oxidative stress, and osteoprotective properties. However, more high-quality animal studies are needed to assess the effect of quercetin on RA. Additionally, the safety of quercetin requires further confirmation. Given the importance of the active ingredient, dose selection and the improvement of quercetin's bioavailability remain to be explored.

Risk stratification and beneficiary selection among elderly nasopharyngeal carcinoma patients from concurrent chemoradiotherapy combined with induction chemotherapy.

OBJECTIVE: This study aims to evaluate the risk stratification among elderly Nasopharyngeal carcinoma (NPC) patients (≥60 years old) and select the beneficiaries from concurrent chemotherapy (CCRT) combined with induction chemotherapy (IC). MATERIALS AND METHODS: A total of 909 elderly non-metastatic NPC patients treated with cisplatin-based CCRT or IC + CCRT between January 2007 and December 2016 were included. Prognostic nomograms were generated according to clinical characteristics and serum biomarkers. The survival outcomes of patients treated with CCRT versus IC + CCRT were compared in three well-matched risk groups (high, medium, and low risk) after PSM analysis. Benefit of IC in people older or younger than 70 years and effect of different IC regimens and cycles on prognosis were analyzed. RESULTS: Nomograms of overall survival (OS) (C-index: 0.64, 95% CI, 0.61-0.89) and disease special survival (DSS) (C-index: 0.65, 95% CI, 0.62-0.71) showed good prognostic accuracy. The nomogram for DSS included variables of age, gender, ACE, EBV DNA, N stage, and T stage. OS included variables of age, smoking history, ACE, ALB, EBV DNA, N stage, and T stage. The corresponding 5-year OS rates of high, medium and low risk groups were 87.4%, 82.2%, and 60.9%, respectively (p < 0.001), while the 5-year DSS rates were 92.2%, 84.3%, and 69.0%, respectively (p < 0.001). In the high risk group, IC + CCRT led to significantly higher 5-year OS and DSS rate compared with CCRT (5-year OS rate, 73.5% versus 51.8%, p = 0.006; 5-year DSS rate, 81.4% versus 61.3%, p = 0.002). While in the medium and low risk groups, OS and DSS were not significantly different (OS: p = 0.259, 0.186; DSS: p = 0.29, 0.094). Subgroup analysis showed in the high risk group, only people younger than 70 years old could benefit from IC. TPF and IC cycles of three could lead to the best survival results. CONCLUSION: Compared with CCRT, OS, and DSS among high risk elderly patients were significantly improved by the addition of IC in patients younger than 70 years old. TPF and three IC cycles were recommended.

Synergistic Effect of Au-PdO Modified Cu-Doped K2W4O13 Nanowires for Dual Selectivity High Performance Gas Sensing.

Both 3-hydroxy-2-butanone and triethylamine are highly toxic and harmful to human health, and their chronic inhalation can cause respiratory diseases, eye lesions, dermatitis, headache, dizziness, drowsiness, and even fatality. Developing sensors for detecting such toxic gases with low power consumption, high response with superselectivity, and stability is crucial for healthcare and environmental monitoring. This study presents a typical gas sensor fabricated based on AuPdO modified Cu-doped K2W4O13 nanowires, which can selectively detect 3-hydroxy-2-butanone and triethylamine at 120 and 200 °C, respectively. The sensor displays excellent sensing performance at reduced operating temperature, high selectivity, fast response/recovery, and stability, which can be attributed to a synergistic effect of Cu dopants and AuPdO nanoparticles on the K2W4O13 host. The enhanced sensing response and selectivity could be attributed to the oxygen vacancies/defects, bandgap excitation, the electronic sensitization, the reversible redox reaction of PdO and Cu, the cocatalytic activity of AuPdO, and Schottky barrier contacts at the interface of tungsten oxide and Au. The significant variations in the activation capacities of Cu-doped K2W4O13, Pd/PdO, and Au nanoparticles toward 3H-2B and TEA, and the diffusion depth of the two gases in the coated sensing layer may cause dual selectivity. The designed gas sensor materials can serve as a sensitive target for detecting toxic biomarkers and hold broad application prospects in food and environmental safety inspection.

Research progress on inflammatory mechanism of primary Sjögren syndrome.

Primary Sjögren syndrome is an autoimmune disease, in which a large number of lymphocytes infiltrate the exocrine glands and cause gland dysfunction. Its pathogenesis is related to the chronic inflammation of the exocrine glands caused by genetic factors, immunodeficiency or viral infection. Long-term inflammation leads to accelerated apoptosis of epithelial cells, disordered gland structure, increased expression of proinflammatory cytokine such as CXC subfamily ligand (CXCL) 12, CXCL13, B cell-activating factor (BAF), interleukin (IL)-6, interferon (IFN)-γ and tumor necrosis factor (TNF)-α in submandibular gland. With the action of antigen-presenting cells such as dendritic cells and macrophages, lymphocytes (mainly B cells) are induced to mature in secondary lymphoid organs and migrate to the submandibular gland to promotes the formation of germinal centers and the synthesis of autoantibodies. Meanwhile, innate lymphocytes, vascular endothelial cells and mucosa-associated constant T cells as important immune cells, also participated in the inflammatory response of the submandibular gland in primary Sjögren syndrome through different mechanisms. This process involves the activation of multiple signal pathways such as JAK/STAT, MAPK/ERK, PI3K/AKT/mTOR, PD-1/PD-L1, TLR/MyD88/NF-κB, BAF/BAF-R and IFN. These signaling pathways interact with each other and are intricately complex, causing lymphocytes to continuously activate and invade the submandibular glands. This article reviews the latest literature to clarify the mechanism of submandibular gland inflammation in primary Sjögren syndrome, and to provide insights for further research.

Anti-proliferation and anti-migration effects of an aqueous extract of Cinnamomi ramulus on MH7A rheumatoid arthritis-derived fibroblast-like synoviocytes through induction of apoptosis, cell arrest and suppression of matrix metalloproteinase.

CONTEXT: Cinnamomi ramulus, the dry twig of Cinnamomum cassia Presl. (Lauraceae), has been reported to exert several activities such as antitumor, anti-inflammatory, and analgesic effects. OBJECTIVE: This study investigates the effects of an aqueous extract of Cinnamomi ramulus (ACR) on rheumatoid arthritis (RA). MATERIALS AND METHODS: TNF-α-induced RA-derived fibroblast-like synoviocyte MH7A cells were incubated with ACR (0.1-2 mg/mL) for 24 h. The proliferation was tested using CCK-8 and colony formation assays. The migration and invasion abilities were measured using transwell tests and wound healing assays. Apoptosis and cell cycle were examined by flow cytometry. The potential mechanisms were determined by western blotting and quantitative real-time PCR. UPLC-QE-MS/MS was used for chromatographic analysis of ACR and its compounds were identified. Molecular docking strategy was used to screen the potential anti-RA active compounds of ACR. RESULTS: We found that ACR induced apoptosis in MH7A cells at concentrations of 0.4, 0.8, and 1.2 mg/mL. The proliferation of MH7A cells was reduced and the cell cycle was blocked in the G2/M phase at concentrations of 0.2, 0.4, 0.6 mg/mL. Migration and invasion of MH7A cells were reduced through inhibiting the expression of MMP-1, MMP-2, and MMP-3. The molecular docking strategy results showed that 9 compounds in ACR have good affinity with protein crystal, and benzyl cinnamate (10-100 µg/mL) could inhibit cell migration and induce apoptosis. CONCLUSIONS: The anti-RA effect of ACR may be attributed to its anti-proliferative and anti-migration effects on synovial fibroblasts. These data suggest that Cinnamomi ramulus may have therapeutic value for the treatment of RA.

WDR63 inhibits Arp2/3-dependent actin polymerization and mediates the function of p53 in suppressing metastasis.

Accumulating evidence suggests that p53 plays a suppressive role in cancer metastasis, yet the underlying mechanism remains largely unclear. Regulation of actin dynamics is essential for the control of cell migration, which is an important step in metastasis. The Arp2/3 complex is a major nucleation factor to initiate branched actin polymerization that drives cell migration. However, it is unknown whether p53 could suppress metastasis through modulating Arp2/3 function. Here, we report that WDR63 is transcriptionally upregulated by p53. We show with migration assays and mouse xenograft models that WDR63 negatively regulates cell migration, invasion, and metastasis downstream of p53. Mechanistically, WDR63 interacts with the Arp2/3 complex and inhibits Arp2/3-mediated actin polymerization. Furthermore, WDR63 overexpression is sufficient to dampen the increase in cell migration, invasion, and metastasis induced by p53 depletion. Together, these findings suggest that WDR63 is an important player in the regulation of Arp2/3 function and also implicate WDR63 as a critical mediator of p53 in suppressing metastasis.

The Effects of Ganglioside-Monosialic Acid in Taxane-Induced Peripheral Neurotoxicity in Patients with Breast Cancer: A Randomized Trial.

BACKGROUND: Taxane-induced peripheral neuropathy (TIPN) is a dose-limiting adverse effect. Ganglioside-monosialic acid (GM1) functions as a neuroprotective factor. We assessed the effects of GM1 on the prevention of TIPN in breast cancer patients. METHODS: We conducted a randomized, double-blind, placebo-controlled trial including 206 patients with early-stage breast cancer planning to receive taxane-based adjuvant chemotherapy with a follow-up of more than 1 year. Subjects were randomly assigned to receive GM1 (80 mg, day -1 to day 2) or placebo. The primary endpoint was the Functional Assessment of Cancer Treatment Neurotoxicity subscale score after four cycles of chemotherapy. Secondary endpoints included neurotoxicity evaluated by National Cancer Institute Common Terminology Criteria for Adverse Events Version 4.0 and the Eastern Cooperative Oncology Group neuropathy scale. All statistical tests were two-sided. RESULTS: In 183 evaluable patients, the GM1 group reported better mean Functional Assessment of Cancer Treatment Neurotoxicity subscale scores than patients in the placebo group after four cycles of chemotherapy (43.27, 95% confidence interval [CI] = 43.05 to 43.49 vs 34.34, 95% CI = 33.78 to 34.89; mean difference = 8.96, 95% CI = 8.38 to 9.54, P < .001). Grade 1 or higher peripheral neurotoxicity in Common Terminology Criteria for Adverse Events v4.0 scale was statistically significantly lower in the GM1 group (14.3% vs 100.0%, P < .001). Additionally, the GM1 group had a statistically significantly lower incidence of grade 1 or higher neurotoxicity assessed by Eastern Cooperative Oncology Group neuropathy scale sensory neuropathy (26.4% vs 97.8%, P < .001) and motor neuropathy subscales (20.9% vs 81.5%, P < .001). CONCLUSIONS: The treatment with GM1 resulted in a reduction in the severity and incidence of TIPN after four cycles of taxane-containing chemotherapy in patients with breast cancer.

Paeoniflorin: a monoterpene glycoside from plants of Paeoniaceae family with diverse anticancer activities.

OBJECTIVES: Paeoniflorin, a representative pinane monoterpene glycoside in plants of Paeoniaceae family, possesses promising anticancer activities on diverse tumours. This paper summarized the advance of Paeoniflorin on cancers in vivo and in vitro, discussed the related molecular mechanisms, as well as suggested some perspectives of the future investigations. KEY FINDINGS: Anticancer activities of paeoniflorin have been comprehensively investigated, including liver cancer, gastric cancer, breast cancer, lung cancer, pancreatic cancer, colorectal cancer, glioma, bladder cancer and leukaemia. Furthermore, the potential molecular mechanisms corresponding to the antitumour effects of Paeoniflorin might be related to the following aspects: inhibition of tumour cell proliferation and neovascularization, induction apoptosis, and inhibition of tumour invasion and metastasis. SUMMARY: Paeoniflorin has wide spectrum antitumour activities; however, in vivo and clinical investigations on antitumour effect of Paeoniflorin are lacking which should be focused on further studies. Our present review on antitumour effects of Paeoniflorin would be beneficial for the further molecular mechanisms study, candidate antitumour drug development and clinical research of Paeoniflorin in the future.

The traditional uses, phytochemistry, pharmacology and toxicology of Cinnamomi ramulus: a review.

OBJECTIVES: Cinnamomi ramulus (called Guizhi in Chinese) is a traditional medicine used to treat gastrointestinal dysfunction, cancer, arthritis, osteoporosis, spleen deficiency, Alzheimer's disease and obesity. This review aimed to provide a systematic summary on the geographical distribution, botany, traditional application, phytochemistry, pharmacology, pharmacokinetics, toxicology and other aspects of Cinnamomi ramulus. KEY FINDING: So far, more than 121 chemical compounds have been isolated from Cinnamomi ramulus, including volatile oil, organic acids, triterpenoid saponins, coumarins, tannins, flavonoids and flavonoid glycosides, steroids and polysaccharides. This paper reviews the pharmacological effects of Cinnamomi ramulus on antibacterial, anti-inflammatory, antiviral, antitumour, antipyretic and analgesic, antidiabetic and antiplatelet aggregation effects. Furthermore, the present review also indicates that Cinnamomi ramulus has the potential to develop into drugs for treating various diseases with high efficacy and low toxicity. SUMMARY: The convictive evidence from modern pharmacology research supports the traditional application of Cinnamomi ramulus. However, further studies on the structure-activity relationship of some of the isolated compounds may improve their biological potency. More toxicological studies will also contribute to the progress of clinical trial studies.

Guizhi-Shaoyao-Zhimu decoction possesses anti-arthritic effects on type II collagen-induced arthritis in rats via suppression of inflammatory reactions, inhibition of invasion & migration and induction of apoptosis in synovial fibroblasts.

BACKGROUND: Rheumatoid arthritis (RA) is a known intractable chronic inflammatory disease of synovial joints characterized by hyperplasia and consecutive inflammation with a high prevalence.Guizhi-Shaoyao-Zhimu (GSZD) is the first choice for clinical treatment of RA in Chinese traditional medicine. This study is aimed to explore the possible pharmacological mechanisms of anti-arthritic effect of GSZD. METHODS: Type II collagen-induced arthritis (CIA) rat model was used to study the anti-arthritic activity of GSZDin vivo, and toe swelling & arthritis score, serum levels of cytokines, and pathological examinations were carried out. In vitro, TNF-α induced MH7A cells were used to study the possible mechanisms of GSZD. The anti-proliferative effects of GSZD were determined by MMT assay, and pro-apoptotic activity of GSZD in MH7A cells was determined by flow cytometry analysis & DAPI staining. Furthermore, the adhesive and invasive abilities of MH7A cells were determined using cell adhesion and transwell assays. MMPs levels were determined by ELISA assays, and mRNA expressions of Caspase-3, -9, Bax, SOCS1, Bcl-2, JAK2, STAT-3 and -5 were determined using qRT-PCR analysis. Besides, the major chemical components in GSZD were analyzed by HPLC-QqQ-MS analysis. RESULTS: Our results showed GSZD reduced the toe swelling & arthritis score, and serum levels of TNF-α, IL-1ß, IL-6 & IL-17a in CIA rats; pathological examination results indicated GSZD improved ankle joint injury in CIA rats.In vitro, GSZD showed significant anti-proliferative and pro-apoptotic effects on TNF-α stimulated MH7A cells. After GSZD treatment, the adhesive and invasive abilities of MH7A cells were reduced, and secretions of MMPs, IL-6 and IL-8 were also reduced. GSZD decreased the releases of TNF-α and IL-1ß in LPS stimulated RAW 264.7 cells. Further studies showed GSZD up-regulated mRNA expressions of Caspase-3, -9, Bax, and SOCS1, whereas down-regulated mRNA expressions of Bcl-2, JAK2, STAT3 and STAT5. Besides, 13 major chemical components were identified in GSZD extracts through HPLC-QqQ-MS analysis. CONCLUSION: Our results suggested GSZD possesses an anti-rheumatic effect on CIA rats, and the possible mechanism is related to inhibiting inflammatory response, inhibiting invasion and migration of synovial fibroblasts, and inducing apoptosis in synovial fibroblasts.

A novel approach to determine two optimal cut-points of a continuous predictor with a U-shaped relationship to hazard ratio in survival data: simulation and application.

BACKGROUND: In clinical and epidemiological researches, continuous predictors are often discretized into categorical variables for classification of patients. When the relationship between a continuous predictor and log relative hazards is U-shaped in survival data, there is a lack of a satisfying solution to find optimal cut-points to discretize the continuous predictor. In this study, we propose a novel approach named optimal equal-HR method to discretize a continuous variable that has a U-shaped relationship with log relative hazards in survival data. METHODS: The main idea of the optimal equal-HR method is to find two optimal cut-points that have equal log relative hazard values and result in Cox models with minimum AIC value. An R package 'CutpointsOEHR' has been developed for easy implementation of the optimal equal-HR method. A Monte Carlo simulation study was carried out to investigate the performance of the optimal equal-HR method. In the simulation process, different censoring proportions, baseline hazard functions and asymmetry levels of U-shaped relationships were chosen. To compare the optimal equal-HR method with other common approaches, the predictive performance of Cox models with variables discretized by different cut-points was assessed. RESULTS: Simulation results showed that in asymmetric U-shape scenarios the optimal equal-HR method had better performance than the median split method, the upper and lower quantiles method, and the minimum p-value method regarding discrimination ability and overall performance of Cox models. The optimal equal-HR method was applied to a real dataset of small cell lung cancer. The real data example demonstrated that the optimal equal-HR method could provide clinical meaningful cut-points and had good predictive performance in Cox models. CONCLUSIONS: In general, the optimal equal-HR method is recommended to discretize a continuous predictor with right-censored outcomes if the predictor has an asymmetric U-shaped relationship with log relative hazards based on Cox regression models.

Andrographolide attenuates imbalance of gastric vascular homeostasis induced by ethanol through glycolysis pathway.

Different kinds of factors contribute to gastric ulcer development which characterized by damaging gastric mucosal layer. However, gastric vascular homeostasis is not well defined and whether andrographolide has a protective function is largely unknown. The goal of this study is to investigate the potential function roles and underlying mechanism by which andrographolide regulates gastric vascular homeostasis in vivo and in vitro. Gastric ulcer animal model induced on andrographolide pretreated C57/BL6 mouse by ethanol intragastric administration. Hematoxylin and Eosin Stain, Masson's trichrome stain and Immunohistochemistry stain performed to observe gastric vascular homeostasis, which associated hemorrhage, extracellular matrix deposition and macrophage infiltration. The activity of vascular endothelial cells were associated with the proliferation and migration, which were detected using cell counting, MTS, and wound scratch healing assay. The underlying endothelial glycolytic mechanism investigated in vivo and in vitro. Andrographolide pretreatment dramatically attenuates ethanol intragastric administration induced imbalance of gastric vascular homeostasis which characterized by severe hemorrhage, increase extracellular matrix deposition and augment macrophage infiltration. Andrographolide treatment conspicuous inhibits HUVEC-C activity characterized by suppressing proliferation and migration of endothelial cells. Mechanically, andrographolide treatment significant suppresses the expression of glycolytic genes, especially decrease PFKFB3 expression. The treatment with PFKFB3 inhibitor, 3-PO, exacerbates the inhibitory function of andrographolide on vascular endothelial cell proliferation and migration. Those data Suggests that andrographolide contributes to maintain gastric vascular homeostasis, at least partially, by inhibiting PFKFB3 mediated glycolysis pathway. Andrographolide plays a crucial role in maintaining gastric vascular homeostasis during gastric ulcer development through regulating vascular endothelial cell glycolytic pathway.

Force Spectroscopy Revealed a High-Gas-Density State near the Graphite Substrate inside Surface Nanobubbles.

The absorption of gas molecules at hydrophobic surfaces may have a special state and play an important role in many processes in interfacial physics, which has been rarely considered in previous theory. In this paper, force spectroscopic experiments were performed by a nanosized AFM probe penetrated into individual surface nanobubbles and contacted with a highly ordered pyrolytic graphite (HOPG) substrate. The results showed that the adhesion force at the gas/solid interface was much smaller than that in air measured with the same AFM probe. The adhesion data were further analyzed by the van der Waals force theory, and the result implied that the gas density near the substrate inside the surface nanobubbles was about 3 orders of magnitude higher than that under the standard pressure and temperature (STP). Our MD simulation indicated that the gas layers near the substrate exhibited a high-density state inside the surface nanobubbles. This high-density state may provide new insight into the understanding of the abnormal stability and contact angle of nanobubbles on hydrophobic surfaces, and have significant impact on their applications.

Crystallographic Analysis of the Catalytic Mechanism of Phosphopantothenoylcysteine Synthetase from Saccharomyces cerevisiae.

Phosphopantothenoylcysteine (PPC) synthetase (PPCS) catalyzes nucleoside triphosphate-dependent condensation reaction between 4'-phosphopantothenate (PPA) and l-cysteine to form PPC in CoA biosynthesis. The catalytic mechanism of PPCS has not been resolved yet. Coenzyme A biosynthesis protein 2 (Cab2) possesses activity of PPCS in Saccharomyces cerevisiae. Our enzymatic assays suggest that Cab2 could utilize both ATP and CTP to activate PPA in vitro. The results of isothermal titration calorimetry indicate that PPA, CTP, and ATP could bind to Cab2 individually, with PPA having the highest binding affinity. To provide further insight into the catalytic mechanism of Cab2, we determined the crystal structures of Cab2 and its complex with PPA, the reaction intermediate 4'-phosphopantothenoyl-CMP, the final reaction product PPC, and the product analogue phosphopantothenoylcystine. Except for PPA, all other ligands were generated in situ and present in the active-site pocket of Cab2. Structures of Cab2 in complex with ligands provide insight into substrates binding and its catalytic mechanism. Analysis of structures indicates that the carboxyl of PPA-moiety of ligands and the γ-amino group of Asn97 possess different conformations in these complex structures. The cysteine/cystine/serine selectivity assays for Cab2 indicate that the amino group rather than the thiol group of l-cysteine attacks the carbonyl of 4'-phosphopantothenoyl-CMP to form PPC. Based on structural and biochemical data, the catalytic mechanism of Cab2 was proposed for the first time.

The C-terminus of ubiquitin plays a critical role in deamidase Lpg2148 recognition.

By bearing a papain-like core structure and a cysteine-based catalytic triad, deamidase can convert glutamine to glutamic acid or asparagine to aspartic acid to modify the functions of host target proteins resulting in the blocking of eukaryotic host cell function. Legionella pneumophila effector Lpg2148 (MvcA) is a deamidase, a structural homolog of cycle inhibiting factor (Cif) effectors. Lpg2148 and Cif effectors are functionally diverse, with Lpg2148 only catalyzing ubiquitin but not NEDD8. However, a detailed understanding of substrate specificity is still missing. Here, we resolved the crystal structure of Lpg2148 at 2.5 Šresolution and obtained rigid-body modeling of Lpg2148 with C-terminus deleted ubiquitin (1-68) (ubΔc) complex using HADDOCK, which shows that the C-terminus of ubiquitin is flexible in recognition. We also conducted the truncated analysis to demonstrate that Leu71 of ubiquitin is necessary for its interaction with Lpg2148. Moreover, Val33 of Lpg2148 at the edge of a channel plays a vital role in the interaction and is limited by the length of the C-terminus of ubiquitin, which may help to explain the selectivity of ubiquitin over NEDD8. In summary, these results enrich our knowledge of substrate recognition of deamidase.