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When hypoxanthine was utilized as the activator for the salvage pathway in cAMP synthesis, xanthine oxidase would generate in quantity leading to low hypoxanthine conversion ratios and cell viability. To enhance cAMP salvage synthesis, fermentations with citrate/luteolin and hypoxanthine coupling added were conducted in a 7 L bioreactor and then multiple physiological indicators of fermentation with luteolin addition were assayed. Due to hypoxanthine feeding, cAMP productivity reached 0.066 g/(L·h) with 43.5% higher than control, however, cAMP synthesis, cell growth and glucose uptake all ceased at 50 h which was shortened by 22 h in comparison to control. The addition of citrate resulted in the cessation of fermentation at 61 h, on the contrary, owing to luteolin addition, cAMP fermentation performance was enhanced significantly during the whole fermentation period (72 h) with higher hypoxanthine conversion ratios and cAMP contents when compared with citrate and only hypoxanthine added batches. Multiple physiological indicators revealed that luteolin inhibited xanthine oxidase activity reducing hypoxanthine decomposition and ROS generation. ATP/AMP, NADH/NAD + and NADPH/NADP + were significantly increased especially at the late phase. Moreover, HPRT, PUP expression contents and corresponding gene transcription levels were also elevated. Luteolin could inhibit xanthine oxidase activity and further decrease hypoxanthine decomposition and ROS generation leading to higher hypoxanthine conversion and less cell damage for cAMP salvage synthesis efficiently., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

The unicellular flagellate algae Poterioochromonas malhamensis is a potential fucoxanthin-rich resource for sustainable and cost-effective fucoxanthin production. Light and nutrients are critical regulators for the accumulation of fucoxanthin in P. malhamensis . In this study, the maximum fucoxanthin yield of 50.5 mg L -1 and productivity of 6.31 mg L -1 d -1 were achieved by coupling high-cell-density fermentation with illumination. It was found that the combined use of organic and inorganic nitrogen (N) nutrition could improve the fucoxanthin yield as single inorganic or organic N had limitation to enhance cell growth and fucoxanthin accumulation. White light was the optimal light quality for fucoxanthin accumulation. Under white light and a moderate light intensity of 150 μmol m -2 s -1 , the highest biomass concentration and fucoxanthin content reached 32.9 g L -1 and 1.56 mg g -1 of dry cell weight (DCW), respectively. This is the first study on effective fucoxanthin production in P. malhamensis by integrating illumination with high-cell-density fermentation, which paved the way for further development of P. malhamensis as a potential source for commercial fucoxanthin production., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jin, Guo, Li, Chen, Ma, Wang, Wang and Yuan.)

Three different types of surface-modified layers of N, C, and N+C are successfully prepared on AerMet100 steel by plasma-assisted thermochemical treatment, and diamond-like carbon (DLC) films are formed on the top surfaces of the latter two. The results show that the DLC films produced by prenitriding and then carburizing (N+C) exhibit a smoother and finer morphology and higher sp 3 content than that without prenitriding (C). In addition, the wear resistance of the N+C specimen with a high hardness nitrided layer as the support for the outermost DLC films is superior to that of the C specimen. In view of the catalytic effect of the Fe 3 C phase on the growth of DLC films, the interfacial properties of Fe 3 C(001)/diamond(111) are investigated using first-principles calculations. On the basis of the most preferred Fe-terminated HCP site model, the effects of alloyed cementite (Fe 2 MC) on interfacial adhesion of Fe 2 MC(001)/diamond(111) are also investigated. Furthermore, the mechanisms of interfacial adhesion for two representative dopings (Zr weakened and V enhanced) are revealed in detail. These results are expected to provide a potential promising means for future experimental works on the preparation of high-performance DLC films on alloy steel surfaces by plasma carburizing.

Background: Current guidelines recommend the use of potent antiplatelet agents in patients undergoing percutaneous coronary intervention (PCI) following an acute coronary syndrome (ACS). However, data about optimal platelet inhibition in severe renal insufficiency patients are scarce. The purpose of this study is to determine if ticagrelor is more effective than clopidogrel in patients with ACS and severe renal insufficiency treated with PCI., Methods: We retrospectively enrolled patients with ACS and severe renal insufficiency (eGFR ≤ 30 ml/min·1.73 m 2 or dialysis) who underwent PCI at our hospital between January 2015 and March 2020. We used the adjusted Cox proportional hazards models to analyze the 1-year outcome endpoints, including the primary endpoint (the composite of cardiovascular death, recurrence of MI, or nonfatal ischemic stroke), death from any cause, and bleeding events (Bleeding Academic Research Consortium, BARC criteria)., Results: A total of 276 patients with ACS and severe renal insufficiency who were treated with PCI with ticagrelor ( n  = 108) or clopidogrel ( n  = 168) were included in the study. After adjustment, there was no statistical difference in risk of the primary endpoint (HR, 0.78; 95% CI, 0.46-1.33; P =0.367) and death from any cause (HR, 0.86; 95% CI, 0.38-1.89; P =0.708) in the ticagrelor group against the clopidogrel group. However, the risk of total bleeding was significantly higher in the ticagrelor group (HR, 3.01; 95% CI, 1.81-5.62; P =0.01). Subgroup analysis according to the confounders did not identify any significant subgroup heterogeneity., Conclusion: Ticagrelor did not improve the major adverse cardiovascular events and all-cause mortality when compared to clopidogrel, but significantly increased the risk of bleeding in Chinese patients with ACS and severe renal insufficiency undergoing PCI., Competing Interests: The authors declare that they have no conflicts of interest to disclose with respect to this manuscript., (Copyright © 2022 Yunxian Chen et al.)

Objectives: In our previous study, citrate was used as auxiliary energy substance for improving cAMP fermentation performance, however, the regulation mechanism of citrate on improved cAMP contents was not clear. To elucidate the regulation mechanism, cAMP fermentations with/without citrate addition were conducted in a 7 L fermentor using Arthrobacter sp. CCTCC 2013431 and assays on key enzymes activities, energy metabolism level, amino acids contents and peroxidation level were performed., Results: With 3 g/L-broth sodium citrate added, cAMP concentration and conversion yield from glucose reached 4.34 g/L and 0.076 g/g which were improved by 30.7% and 29.8%, respectively, when compared with those of control. Citrate changed carbon flux distribution among different routes and more carbon flux was directed into pentose phosphate pathway beneficial to cAMP synthesis. Meanwhile, energy metabolism together with precursor amino acids levels were improved significantly owing to strengthened metabolic intensity of tricarboxylate cycle by exogenous citrate utilization which provided energy and substance basis for cAMP production. Moreover, higher glutamate synthesis and oxidative stress caused by citrate addition consumed excessive NADPH derived from pentose phosphate pathway by which feedback suppression for pentose phosphate pathway was relieved efficiently., Conclusion: Citrate promoted cAMP fermentation production by Arthrobacter sp. CCTCC 2013431 due to enhanced precursor amino acids, energy metabolism level and relieved feedback suppression for pentose phosphate pathway., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Gouty arthritis is characterized by the deposition of monosodium urate (MSU) within synovial joints and tissues due to increased urate concentrations. In this study, we explored the effect of the natural compound curcumin on the MSU crystal-stimulated inflammatory response., Methods: THP-1-derived macrophages and murine RAW264.7 macrophages were pretreated with curcumin for 1 h and then stimulated with MSU suspensions for 24 h. The protein level of TLR4, MyD88, and IκBα, the activation of the NF-κB signaling pathway, the expression of the NF-κB downstream inflammatory cytokines, and the activity of NLRP3 inflammasome were measured by western blotting and ELISA. THP-1 and RAW264.7 cells were loaded with MitoTracker Green to measure mitochondrial content, and MitoTracker Red to detect mitochondrial membrane potential. To measure mitochondrial reactive oxygen species (ROS) levels, cells were loaded with MitoSOX Red, which is a mitochondrial superoxide indicator. The effects of curcumin on mouse models of acute gout induced by the injection of MSU crystals into the footpad and synovial space of the ankle, paw and ankle joint swelling, lymphocyte infiltration, and MPO activity were evaluated., Results: Curcumin treatment markedly inhibited the degradation of IκBα, the activation of NF-κB signaling pathway, and the expression levels of the NF-κB downstream inflammatory genes such as IL-1β, IL-6, TNF-α, COX-2, and PGE2 in the MSU-stimulated THP-1-derived macrophages. Curcumin administration protected THP-1 and RAW264.7 cells from MSU induced mitochondrial damage through preventing mitochondrial membrane potential reduction, decreasing mitochondria ROS, and then inhibited the activity of NLRP3 inflammasome. Intraperitoneal administration of curcumin alleviated MSU crystal-induced paw and ankle joint swelling, inflammatory cell infiltration, and MPO activity in mouse models of acute gout. These results correlated with the inhibition of the degradation of IκBα, the phosphorylation levels of NF-κB subunits (p65 and p50), and the activity of NLRP3 inflammasome., Conclusion: Curcumin administration effectively alleviated MSU-induced inflammation by suppressing the degradation of IκBα, the activation NF-κB signaling pathway, the damage of mitochondria, and the activity of NLRP3 inflammasome. Our results provide a new strategy in which curcumin therapy may be helpful in the prevention of acute episodes of gout.

Acute gouty arthritis (AGA) is an auto-inflammatory disease characterized by resolving spontaneously, which suggests that negative feedback loops control inflammatory and immunological responses to monosodium urate (MSU) crystals. By now, the molecular mechanism for spontaneous resolution of acute GA remains unclear; this study was undertaken to evaluate whether IL-37 is involved in spontaneous resolution of AGA. A total of 45 acute GA (AGA),29 non-acute GA (NAGA) male patients and 82 male health control (HC) were involved in this study, we measured IL-7 expression in the peripheral blood mononuclear cells (PBMCs), together with levels of IL-1β, IL-6, IL-10, TNF-α and TGF-β1 in the serum. Further, we either inhibited IL-37 expression in human PBMCs with siRNA or over-expressed the cytokine in human macrophages. Pro-inflammatory cytokine IL-1β, IL-6, and TNF-α expressions were significantly higher in the AGA group than in the NAGA or HC group (P < 0.05, respectively). However, anti-inflammatory IL-37, TGF-β1, and IL-10 were greater in the NAGA group than in the AGA and HC groups (P < 0.05, respectively). Expression of IL-37 in MSU crystal-treated macrophages inhibited the expression of pro-inflammatory cytokines, whereas the abundance of these cytokines increased with silencing of endogenous IL-37 in human blood cells. However, anti-inflammatory TGF-β1 and IL-10 expressions in these supernatants were unaffected by over-expression or knockdown of IL-37. Our study indicates that IL-37 is an important anti-inflammatory cytokine in AGA by suppressing the production of pro-inflammatory cytokines. Thus, IL-37 may provide a novel research target for the pathogenesis and therapy of GA.

Atrial fibrillation (AF) is the most common sustained arrhythmia causing high morbidity and mortality. While changing of the cellular calcium homeostasis plays a critical role in AF, the L-type calcium channel α1c protein has suggested as an important regulator of reentrant spiral dynamics and is a major component of AF-related electrical remodeling. Our computational modeling predicted that miRNA-223 may regulate the CACNA1C gene which encodes the cardiac L-type calcium channel α1c subunit. We found that oxidized low-density lipoprotein (ox-LDL) cholesterol significantly up-regulates both the expression of miRNA-223 and L-type calcium channel protein. In contrast, knockdown of miRNA-223 reduced L-type calcium channel protein expression, while genetic knockdown of endogenous miRNA-223 dampened AF vulnerability. Transfection of miRNA-223 by adenovirus-mediated expression enhanced L-type calcium currents and promoted AF in mice while co-injection of a CACNA1C-specific miR-mimic counteracted the effect. Taken together, ox-LDL, as a known factor in AF-associated remodeling, positively regulates miRNA-223 transcription and L-type calcium channel protein expression. Our results implicate a new molecular mechanism for AF in which miRNA-223 can be used as an biomarker of AF rheumatic heart disease.

Glut9 is highly expressed in the human kidney proximal convoluted tubular and plays a crucial role in the regulation of plasma urate levels. The gene effects were stronger among women. Our results show that 17-β-estradiol (E2) through ER (estrogen receptor) β downregulates Glut9 protein expression on human renal tubular epithelial cell line (HK2). Intriguingly, E2 does not affect the expression of Glut9 mRNA. ERβ is linked to PTEN, the PTEN gene negatively regulates the PI3K/AKT pathway, and the PI3K/AKT pathway inhibition may lead to autophagy. Further study indicates that ERβ may affect the expression of Glut9 though autophagy.

Antibody-based immunotherapy has been effectively used for tumor treatment. However, to date, only a few tumor-associated antigens (TAAs) or therapeutic targets have been identified. Identification of more immunogenic antigens is essential for improvements in multiple myeloma (MM) diagnosis and therapy. In this study, we synthesized a polyclonal antibody (PAb) by immunizing rabbits with whole human plasmacytoma ARH-77 cells and identified MM-associated antigens, including enlonase, adipophilin, and HSP90s, among others, via proteomic technologies. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that 200 µg/mL PAb inhibits the proliferation of ARH-77 cells by over 50% within 48 h. Flow cytometric assay indicated that PAb treatment significantly increases the number of apoptotic cells compared with other treatments (52.1% vs. NS, 7.3% or control rabbit IgG, 9.9%). In vivo, PAb delayed tumor growth and prolonged the lifespan of mice. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that PAb also induces statistically significant changes in apoptosis compared with other treatments (P<0.05). We therefore conclude that PAb could be used for the effective screening and identification of TAA. PAb may have certain anti-tumor functions in vitro and in vivo. As such, its combination with proteomic technologies could be a promising approach for sieving TAA for the diagnosis and therapy of MM.