FPR1 Antagonist (BOC-MLF) Inhibits Amniotic Epithelial-mesenchymal Transition.

OBJECTIVE: Premature rupture of membranes (PROM) is a common pregnancy disorder that is closely associated with structural weakening of fetal membranes. Studies have found that formyl peptide receptor 1 (FPR1) activates inflammatory pathways and amniotic epithelialmesenchymal transition (EMT), stimulates collagen degradation, and leads to membrane weakening and membrane rupture. The purpose of this study was to investigate the anti-inflammatory and EMT inhibitory effects of FPR1 antagonist (BOC-MLF) to provide a basis for clinical prevention of PROM. METHODS: The relationship between PROM, FPR1, and EMT was analyzed in human fetal membrane tissue and plasma samples using Western blotting, PCR, Masson staining, and ELISA assays. Lipopolysaccharide (LPS) was used to establish a fetal membrane inflammation model in pregnant rats, and BOC-MLF was used to treat the LPS rat model. We detected interleukin (IL)-6 in blood from the rat hearts to determine whether the inflammatory model was successful and whether the anti-inflammatory treatment was effective. We used electron microscopy to analyze the structure and collagen expression of rat fetal membrane. RESULTS: Western blotting, PCR and Masson staining indicated that the expression of FPR1 was significantly increased, the expression of collagen was decreased, and EMT appeared in PROM. The rat model indicated that LPS caused the collapse of fetal membrane epithelial cells, increased intercellular gaps, and decreased collagen. BOC-MLF promoted an increase in fetal membrane collagen, inhibited EMT, and reduced the weakening of fetal membranes. CONCLUSION: The expression of FPR1 in the fetal membrane of PROM was significantly increased, and EMT of the amniotic membrane was obvious. BOC-MLF can treat inflammation and inhibit amniotic EMT.

Comparison of ultrasound features and lesion sites in dysfunctional arteriovenous fistula.

This study aimed to investigate ultrasound features of arteriovenous fistula stenosis and their relationship with primary patency after percutaneous transluminal angioplasty (post-intervention primary patency) and compare this classification with that using lesion location. Hemodialysis patients who underwent ultrasound-guided percutaneous transluminal angioplasty for arteriovenous fistula stenosis from July 2020 to December 2021 were retrospectively evaluated. Lesions (excluding inflow arteries) were categorized into five groups based on ultrasound features, and the clinical characteristics and risk factors affecting the post-intervention primary patency of the arteriovenous fistula were analyzed. Among 185 patients, 100 (54.05%), 36 (19.46%), 22 (11.89%), 11 (5.95%), and 16 (8.65%) were classified into the intima-dominant, non-intima-dominant, valve obstruction, vascular calcification, and mixed groups, respectively. The dialysis duration and arteriovenous fistula use time were the highest in the vascular calcification group at 86 (interquartile range: 49-140) and 77 (interquartile range: 49-110) months, respectively. Diabetes mellitus was most common in the intima-dominant group (42.0%). In Kaplan-Meier and univariate Cox analysis, type III lesion location (stenosis in the venous confluence site) was associated with the lower post-intervention primary patency. In the multivariate Cox analysis, percutaneous transluminal angioplasty times (the number of times patients were treated with percutaneous transluminal angioplasty for arteriovenous fistula stenosis dysfunction), vascular calcification, calcification at the lesion site requiring percutaneous transluminal angioplasty, and serum parathyroid hormone levels were independent risk factors for post-intervention primary patency. Ultrasound features showed that calcification of the arteriovenous fistula was detrimental to the post-intervention primary patency of arteriovenous fistula.

Effect of sacubitril valsartan on heart failure with mid-range or preserved ejection fraction in patients on maintenance hemodialysis: real-world experience in a single-center, prospective study.

BACKGROUND: This study aimed to evaluate the effect of sacubitril valsartan (SV) on heart failure (HF) hospitalization and cardiovascular mortality in patients on hemodialysis with HF with preserved ejection fraction (EF; HFpEF). METHODS: This single-center, prospective study enrolled 155 stable hemodialysis patients with EF > 40% who were followed up for 12 months. Fifty-nine patients were treated with SV; the others were matched for EF (57.89 ± 9.35 vs. 58.00 ± 11.82, P = 0.9) at a ratio of 1:1 and included as controls. The target dosage of SV was 200 mg/day. RESULTS: Twenty-three (23/155; 14.84%) had HF with mid-range EF (HFmrEF), while 132 (85.16%) had HFpEF. After SV treatment, the peak early diastolic transmitral flow velocity/peak early diastolic mitral annular tissue velocity(E/e') improved from 17.19 ± 8.74 to 12.80 ± 5.52 (P = 0.006), the left ventricular (LV) end-diastolic diameter decreased from 53.14 ± 7.67 mm to 51.56 ± 7.44 mm (P = 0.03), and the LV mass index decreased from 165.7 ± 44.6 g/m2 to 154.8 ± 24.0 g/m2 (P = 0.02). LVEF (P = 0.08) and LV global longitudinal strain (P = 0.7) did not change significantly. The composite outcome of first and recurrent HF hospitalization or cardiovascular death showed no difference between group. However, the Acute Dialysis Quality Initiative Workgroup (ADQI) HF class improved in 39 and 15 patients and worsened in 1 and 11 patients in the SV and control groups, respectively (P < 0.001). Age, diabetes mellitus, and pulmonary arterial pressure were independent risk factors for HF hospitalization and cardiovascular mortality in patients with HFpEF. CONCLUSIONS: SV improved LV hypertrophy, diastolic function, and the ADQI class for HF; however, it failed to reduce the composite endpoints of HF hospitalization and cardiovascular disease-related mortality over 12 months of follow-up in patients on maintenance hemodialysis with EF of > 40%.

Effect of proximal artery restriction on flow reduction and cardiac function in hemodialysis patients with high-flow arteriovenous fistulas.

OBJECTIVE: Arteriovenous fistula is the preferred vascular access for hemodialysis patients. High-flow arteriovenous fistula may cause high-output heart failure. Various procedures are used to reduce high-flow arteriovenous fistula. This study aimed to assess the efficacy of proximal artery restriction combined with distal artery ligation on flow reduction for high-flow arteriovenous fistula and on cardiac function and echocardiographic changes in patients undergoing hemodialysis. METHODS: A retrospective analysis was performed on data collected from the medical records of patients undergoing hemodialysis with heart failure and high-flow arteriovenous fistula between May 2018 and May 2021. Thirty-one patients were treated with proximal artery restriction (banding juxta-anastomosis of the proximal artery) combined with distal artery ligation (anastomosis distal artery ligation). Changes in the Acute Dialysis Quality Initiative Workgroup cardiac function class, blood pressure, and echocardiography before and 6 months after flow restriction were compared, and post-intervention primary patency was followed-up. RESULTS: The technical success rate of the surgery was 100%, and no surgery-related adverse events occurred. Blood flow and blood flow/cardiac output decreased significantly after flow restriction. Blood flow decreased from 2047.21 ± 398.08 mL/min to 1001.36 ± 240.42 mL/min, and blood flow/cardiac output decreased from 40.18% ± 6.76% to 22.34% ± 7.21% (P < .001). Post-intervention primary patency of arteriovenous fistula at 6, 12, and 24 months was 96.8%, 93.5%, and 75.2%, respectively. The Acute Dialysis Quality Initiative Workgroup cardiac function class improved significantly after 6 months of flow restriction (P < .001). The systolic and diastolic left heart function improved, as evidenced by a significant decrease in left atrial volume index, left ventricular end-diastolic/end-systolic diameters, left ventricular end-diastolic volume, left ventricular mass index, cardiac output, and cardiac index and an increase in lateral peak velocity of longitudinal contraction, average septal-lateral s', and lateral early diastolic peak velocity after flow restriction (P < .05). Systolic pulmonary artery pressure decreased from 32.36 ± 8.56 mmHg to 27.57 ± 8.98 mmHg (P < .05), indicating an improvement in right heart function. CONCLUSIONS: Proximal artery restriction combined with distal artery ligation effectively reduced the blood flow of high-flow arteriovenous fistula and improved cardiac function.

Synthesis and anticancer mechanisms of zinc(II)-8-hydroxyquinoline complexes with 1,10-phenanthroline ancillary ligands.

Twenty new zinc(II) complexes with 8-hydroxyquinoline (H-Q1-H-Q6) in the presence of 1,10-phenanthroline derivatives (D1-D10) were synthesized and formulated as [Zn(Q1)2(D1)] (DQ1), [Zn(Q2)2(D2)]·CH3OH (DQ2), [Zn(Q1)2(D3)] (DQ3), [Zn(Q1)2(D4)] (DQ4), [Zn(Q3)2(D5)] (DQ5), [Zn(Q3)2(D4)] (DQ6), [Zn(Q4)2(D5)]·CH3OH (DQ7), [Zn(Q4)2(D6)] (DQ8), [Zn(Q4)2(D3)]·CH3OH (DQ9), [Zn(Q4)2(D1)]·H2O (DQ10), [Zn(Q5)2(D4)] (DQ11), [Zn(Q6)2(D6)]·CH3OH (DQ12), [Zn(Q5)2(D2)]·5CH3OH·H2O (DQ13), [Zn(Q5)2(D7)]·CH3OH (DQ14), [Zn(Q5)2(D8)]·CH2Cl2 (DQ15), [Zn(Q5)2(D9)] (DQ16), [Zn(Q5)2(D1)] (DQ17), [Zn(Q5)2(D5)] (DQ18), [Zn(Q5)2(D10)]·CH2Cl2 (DQ19) and [Zn(Q5)2(D3)] (DQ20). They were characterized using multiple techniques. The cytotoxicity of DQ1-DQ20 was screened using human cisplatin-resistant SK-OV-3/DDP ovarian cancer (SK-OV-3CR) cells and normal hepatocyte (HL-7702) cells. Complex DQ6 showed low IC50 values (2.25 ± 0.13 µM) on SK-OV-3CR cells, more than 3.0-8.0 times more cytotoxic than DQ1-DQ5 and DQ7-DQ20 (≥6.78 µM), and even 22.2 times more cytotoxic than the standard cisplatin, the corresponding free H-Q1-H-Q6 and D1-D10 alone (>50 µM). As a comparison, DQ1-DQ20 displayed nontoxic rates against healthy HL-7702 cells. Furthermore, DQ6 and DQ11 induced significant apoptosis via mitophagy pathways. DQ6 also significantly inhibited tumor growth in an in vivo SK-OV-3-xenograft model (ca. 49.7%). Thus, DQ6 may serve as a lead complex for the discovery of new antitumor agents.

Prognosis of Heart Valve Calcification on Cardiovascular Events in Hemodialysis Patients without Central Venous Catheters.

INTRODUCTION: Heart valvular calcification (HVC) is an important predictor of cardiovascular events (CEs) and all-cause mortality in dialysis patients. Patients in the early stage of dialysis or those with central venous catheters (CVC) are also at high risk of cardiovascular and all-cause mortality. It could be a confounding factor for the prognosis of HVC on CE. METHODS: From March 2017 to April 2022, the prognosis of HVC on CE and all-cause mortality was studied retrospectively in 158 hemodialysis (HD) patients who used arteriovenous fistulas or arteriovenous grafts as vascular access and entered HD for more than 12 months. RESULTS: Out of 158 patients, 70 (44.3%) were diagnosed with HVC via echocardiography. A total of 180 CEs occurred during follow-up. Among them, acute heart failure accounted for 62.66%, and its prevalence was significantly higher in the HVC group than that in the non-HVC group (p < 0.0001). The cumulative incidence of CE-free survival in the HVC group was significantly lower than that in the non-HVC group (p = 0.030). Only 11 patients died, and there was no significant difference in all-cause mortality between the two groups (p = 0.560). Multivariate COX regression analyses showed that HD vintage, mitral valve calcification, and aortic valve regurgitation (AR)/aortic valve stenosis (AS) but not aortic valve calcification were risk factors for CE (p < 0.05). CONCLUSION: After excluding the factors of the early stage of HD and CVC, HVC remained a predictor of adverse CE in HD patients.

Down-regulation of HuR inhibits pathological angiogenesis in oxygen-induced retinopathy.

HuR (also known as ELAV1), a ubiquitous RNA-binding protein, is implicated in the pathogenesis of diverse diseases via the mechanism of post-transcriptional regulation. Whether it is involved in pathological angiogenesis in oxygen-induced retinopathy is not clear. In this study, we detected HuR expression was increased in the retina of mouse model of oxygen-induced retinopathy (OIR) as well as in vascular endothelial cells exposed to hypoxia. With gain-of-function and loss-of-function studies using adenovirus infection, we found HuR over-expression promoted while HuR knockdown inhibited the migration, proliferation and tube formation of vascular endothelial cells. Moreover, HuR regulated the expression of VEGFA in vascular endothelial cells. We also found the retinal pathological angiogenesis in mouse OIR model was greatly reduced with HuR knockdown using recombinant AAV expressing HuR specific shRNA which was administered by intravitreal injection. The results of this study suggest HuR is involved in pathological angiogenesis via regulating angiogenic behaviors of endothelial cells, providing a potential target for the treatment of retinopathy of prematurity.

Ferrostatin-1 attenuates pathological angiogenesis in oxygen-induced retinopathy via inhibition of ferroptosis.

Retinopathy of prematurity (ROP) is a vision-threatening ocular disease that occurs in premature infants, but the underlying mechanism is still unclear. Since oxidative stress has been well documented in the ROP development, we aimed to investigate whether ferroptosis, a new type of cell death characterized by lipid peroxidation and iron overload, is also involved in ROP. We detected the lipid peroxidation, oxidative stress and the expression of ferroptosis markers in the retina of mouse model of oxygen-induced retinopathy. After ferroptosis inhibitor, ferrostatin-1, was administered by intravitreal injection, ferroptosis marker, lipid peroxidation, retinal vasculature and glial cell activation were examined. We found decreased expression of SLC7A11 and GPX4, increased expression of FTH1 and TFRC, as well as increase of lipid peroxidation in the retina of OIR mice. Ferrostatin-1 administration significantly reduced lipid peroxidation, and also reversed the change of ferroptosis marker. Neovascular area and avascular area were suppressed and the pathological vasculature changes including acellular vessels and ghost pericytes were decreased. Microglial cell and Müller cell activation was not evidently influenced by ferrostatin-1 treatment. Our findings suggest that ferroptosis is involved in the pathological angiogenesis and might be a promising target for ROP therapy.

Novel glycosylation zinc(II)-cryptolepine complexes perturb mitophagy pathways and trigger cancer cell apoptosis and autophagy in SK-OV-3/DDP cells.

With the aim of shedding some light on the mechanism of action of zinc(II) complexes in antiproliferative processes and molecular signaling pathways, three novel glycosylated zinc(II)-cryptolepine complexes, i.e., [Zn(QA1)Cl2] (Zn(QA1)), [Zn(QA2)Cl2] (Zn(QA2)), and [Zn(QA3)Cl2] (Zn(QA3)), were prepared by conjugating a glucose moiety with cryptolepine, followed by complexation of the resulting glycosylated cryptolepine compounds N-((1-(2-morpholinoethyl)-1H-1,2,3-triazol-4-yl)methyl)-benzofuro[3,2-b]quinolin-11-amine (QA1), 2-(4-((benzofuro[3,2-b]quinolin-11-ylamino)methyl)-1H-1,2,3-triazol-1-yl)ethan-1-ol (QA2), and (2S,3S,4R,5R,6S)-2-(4-((benzofuro[3,2-b]quinolin-11-ylamino)-methyl)-1H-1,2,3-triazol-1-yl)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol (QA3) with zinc(II), and their anticancer activity was evaluated. In MTT assays, Zn(QA1)-Zn(QA3) were more active against cisplatin-resistant ovarian SK-OV-3/DDP cancer cells (SK-OV-3cis) than ZnCl2 and the QA1-QA3 ligands, with IC50 values of 1.81 ± 0.50, 2.92 ± 0.32, and 1.01 ± 0.11 µM, respectively. Complexation of glycosylated cryptolepine QA3 with zinc(II) increased the antiproliferative activity of the ligand, suggesting that Zn(QA3) could act as a chaperone to deliver the active ligand intracellularly, in contrast with other cryptolepine metal complexes previously reported. In vivo and in vitro investigations suggested that Zn(QA3) exhibited enhanced anticancer activity with treatment effects comparable to those of the clinical drug cisplatin. Furthermore, Zn(QA1)-Zn(QA3) triggered SK-OV-3cis cell apoptosis through mitophagy pathways in the order Zn(QA1) > Zn(QA1) > Zn(QA2). These results demonstrate the potential of glycosylated zinc(II)-cryptolepine complexes for the development of chemotherapy drugs against cisplatin-resistant SK-OV-3cis cells.

Cost-effectiveness of artificial intelligence screening for diabetic retinopathy in rural China.

BACKGROUND: Diabetic retinopathy (DR) has become a leading cause of global blindness as a microvascular complication of diabetes. Regular screening of diabetic retinopathy is strongly recommended for people with diabetes so that timely treatment can be provided to reduce the incidence of visual impairment. However, DR screening is not well carried out due to lack of eye care facilities, especially in the rural areas of China. Artificial intelligence (AI) based DR screening has emerged as a novel strategy and show promising diagnostic performance in sensitivity and specificity, relieving the pressure of the shortage of facilities and ophthalmologists because of its quick and accurate diagnosis. In this study, we estimated the cost-effectiveness of AI screening for DR in rural China based on Markov model, providing evidence for extending use of AI screening for DR. METHODS: We estimated the cost-effectiveness of AI screening and compared it with ophthalmologist screening in which fundus images are evaluated by ophthalmologists. We developed a Markov model-based hybrid decision tree to analyze the costs, effectiveness and incremental cost-effectiveness ratio (ICER) of AI screening strategies relative to no screening strategies and ophthalmologist screening strategies (dominated) over 35 years (mean life expectancy of diabetes patients in rural China). The analysis was conducted from the health system perspective (included direct medical costs) and societal perspective (included medical and nonmedical costs). Effectiveness was analyzed with quality-adjusted life years (QALYs). The robustness of results was estimated by performing one-way sensitivity analysis and probabilistic analysis. RESULTS: From the health system perspective, AI screening and ophthalmologist screening had incremental costs of $180.19 and $215.05 but more quality-adjusted life years (QALYs) compared with no screening. AI screening had an ICER of $1,107.63. From the societal perspective which considers all direct and indirect costs, AI screening had an ICER of $10,347.12 compared with no screening, below the cost-effective threshold (1-3 times per capita GDP of Chinese in 2019). CONCLUSIONS: Our analysis demonstrates that AI-based screening is more cost-effective compared with conventional ophthalmologist screening and holds great promise to be an alternative approach for DR screening in the rural area of China.

Study on plasma exosome biomarkers of pregnant women with intrahepatic cholestasis of pregnancy.

OBJECTIVE AND AIMS: Serum total bile acid (TBA) level as the main index for the diagnosis of intrahepatic cholestasis of pregnancy (ICP) has some limitations. The early diagnosis and new treatment of ICP still need to be further strengthened. MATERIALS AND METHODS: Plasma samples were collected, and exosomes were isolated. Key differential proteins were screened by bioinformatics methods. ELISA method was used to detect the concentration of the key differential protein in plasma samples, and the receiver operating characteristic curve (ROC) curve was drawn to find out the best critical value. RESULTS: There were 138 differentially expressed proteins between the ICP and the normal groups by quantitative analysis. Cluster protein (CLU) was screened as a clinical validation index. The CLU concentration of plasma exosomes in the ICP group was significantly higher than that in the normal group (p < .0001). ROC curve analysis showed that the best critical point for diagnosing ICP according to the plasma exosomes CLU concentration of pregnant women was 255.28 ng/ml. In the ICP group, the best crucial point for predicting ICP with premature delivery is 286.72 ng/ml. CONCLUSIONS: The plasma exosomes CLU in pregnant women with ICP is an important biomarker for clinical diagnosis and prediction of premature delivery of ICP.

Knockdown of FBI-1 Inhibits the Warburg Effect and Enhances the Sensitivity of Hepatocellular Carcinoma Cells to Molecular Targeted Agents via miR-3692/HIF-1α.

The transcription suppressor factor FBI-1 (the factor that binds to inducer of short transcripts-1) is an important regulator of hepatocellular carcinoma (HCC). In this work, the results showed that FBI-1 promoted the Warburg effect and enhances the resistance of hepatocellular carcinoma cells to molecular targeted agents. Knockdown of FBI-1 via its small-interfering RNA (siRNA) inhibited the ATP level, lactate productions, glucose uptake or lactate dehydrogenase (LDH) activation of HCC cells. Transfection of siFBI-1 also decreased the expression of the Warburg-effect-related factors: hypoxia-inducible factor-1 alpha (HIF-1α), lactate dehydrogenase A (LDHA), or GLUT1, and the epithelial-mesenchymal transition-related factors, Vimentin or N-cadherin. The positive correlation between the expression of FBI-1 with HIF-1α, LDHA, or GLUT1 was confirmed in HCC tissues. Mechanistically, the miR-30c repressed the expression of HIF-1α by binding to the 3'-untranslated region (3'-UTR) of HIF-1α in a sequence-specific manner, and FBI-1 enhanced the expression of HIF-1α and HIF-1α pathway's activation by repressing the expression of miR. By modulating the miR-30c/HIF-1α, FBI-1 promoted the Warburg effect or the epithelial-mesenchymal transition of HCC cells and promoted the resistance of HCC cells to molecular targeted agents.

Changes in Conjunctival Microbiota Associated With HIV Infection and Antiretroviral Therapy.

Purpose: HIV infection is associated with a variety of ocular surface diseases. Understanding the difference of the ocular microbiota between HIV-infected and healthy individuals as well as the influence of antiretroviral therapy will help to investigate the pathogenesis of these conditions. Methods: A cross-sectional study was conducted on subjects including HIV-negative individuals, untreated HIV-infected individuals, and HIV-infected individuals with antiretroviral therapy. Conjunctival microbiota was assessed by bacterial 16S rRNA sequencing of the samples obtained from the conjunctival swab. Results: The microbial richness in ocular surface was similar in HIV-negative, untreated HIV-positive, and highly active antiretroviral therapy (HAART) subjects. The bacterial compositions were similar in the two HIV infection groups but were significantly different from the HIV-negative group. HAART changed the beta diversity of bacterial community as determined by Shannon index. CD4+ T cell count had no significant influence on the diversity of ocular microbiota in HIV-infected individuals. Conclusions: The data revealed the compositional and structural difference in conjunctival microbial community in subjects with and without HIV infection, indicating that HIV infection or its treatment, may contribute to ocular surface dysbiosis.

Differentially expressed circRNA and functional pathways in the hippocampus of epileptic mice based on next-generation sequencing.

Epilepsy is a clinical syndrome caused by the highly synchronized abnormal discharge of brain neurons. It has the characteristics of paroxysmal, transient, repetitive, and stereotyped. Circular RNAs (circRNAs) are a recently discovered type of noncoding RNA with diverse cellular functions related to their excellent stability; additionally, some circRNAs can bind and regulate microRNAs (miRNAs). The present study was designed to screen the differentially expressed circRNA in an acute seizure model of epilepsy in mice, analyze the related miRNA and mRNA, and study their participating functions and enrichment pathways. In order to obtain the differential expression of circRNA in epilepsy and infer their function, we used next-generation sequencing and found significantly different transcripts. CIRI (circRNA identifier) software was used to predict circRNA from the hippocampus cDNA, EdgeR was applied for the differential circRNA analysis between samples, and Cytoscape 3.7.2 software was used to draw the network diagram. A total of 10,388 differentially expressed circRNAs were identified, of which 34 were upregulated and 66 were downregulated. Among them, mm9_circ_008777 and mm9_circ_004424 were the key upregulated genes, and their expression in the epilepsy group was verified using Quantitative real-time PCR (QPCR). The analysis indicated that the extracted gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways were closely related to several epilepsy-associated processes. This study determined that mm9_circ_008777 and mm9_circ_004424 are potential biomarkers of epilepsy, which play important roles in epilepsy-related pathways. These results could help improve the understanding of the biological mechanisms of circRNAs and epilepsy treatments.

Cloning and Heterologous Expression of a Novel Xylanase Gene TAX1 from Trichoderma atroviride and Its Application in the Deconstruction of Corn Stover.

Xylanase plays a vital role in the efficient utilization of xylan, which accounts for up to 30% of plant dry matter. However, the production cost of xylanase remains high, and the enzymatic characteristics of xylanases of most microorganisms are not suitable for industrial production. Therefore, it is of great significance to discover and develop new and efficient xylanases. In this study, the xylanase gene TAX1 (672 bp cDNA) was cloned from Trichoderma atroviride 3.3013 and expressed in Pichia pastoris. The TAX1 gene encoded a 223-amino acid protein (TAX1) with a molecular weight of 24.2 kDa which showed high similarity to glycoside hydrolase family 11. Enzyme activity assay verified that the recombinant xylanase TAX1 had optimal activity (215.3 IU/mL) at 50°C and pH 6.0. Stable working conditions were measured as pH 4.0-7.0 and 40-60°C. By adding Zn2+, the relative enzymatic activity of recombinant TAX1 was enhanced by 26%. The recombinant xylanase showed high activity toward birchwood xylan and corn stover. The Km and Kcat for xylan and corn stover were 0.36 mg/mL and 0.204 S-1 and 0.48 mg/mL and 0.149 S-1, respectively. The enzymatic activity of the TAX1 produced by P. pastoris was about 2.4-4 times higher that directly isolated from T. atroviride, so engineered P. pastoris for xylanase production could be an ideal candidate for industrial enzyme production.

Bioequivalence and Pharmacokinetic Evaluation of Two Metformin Hydrochloride Tablets Under Fasting and Fed Conditions in Healthy Chinese Volunteers.

This article aims to assess the bioequivalence of the test and the reference metformin hydrochloride tablets in healthy Chinese volunteers under fasting and fed conditions and to explore the effect of food on the pharmacokinetic (PK) profiles of both formulations. In total, 56 healthy Chinese subjects (28 in each group) were enrolled in this randomized, open, single-center, single-dose, 2-treatment, 2-sequence, 2-cycle cross clinical trial. The subjects were administrated a single dose of the test and the reference tablets at 0.25 g with a 7-day washout. Venous blood samples of all subjects were taken from predose 0 hour to postdose 24 hours according to the planned times. PK parameters for metformin were analyzed and calculated with noncompartmental methods. There were no significant differences in the PK parameters between the 2 formulations under both the fasting and the fed states. The 90% confidence intervals of 2 formulations were within 80.00%-125.00% based on Cmax , AUC0-t , and AUC0-∞ under both conditions. High-fat and high-calorie diets delayed the Tmax and reduced the AUC0-t and AUC0-∞ . No severe adverse events occurred in this study. Two metformin hydrochloride tablets were bioequivalent under both fasting and fed states; the high-fat and high-calorie diet could lower the rate and extent of absorption of metformin in healthy Chinese volunteers.

LC-MS based metabolomics reveals metabolic pathway disturbance in retinal pigment epithelial cells exposed to hydroxychloroquine.

Hydroxychloroquine (HCQ) is frequently used medications for many auto-immunity diseases. However, HCQ induced retinal toxicity, which might result in irreversible retinopathy, is one of the most important complications of HCQ. However, the molecular mechanism underlying the HCQ retinal toxicity is still not well known. Retinal pigment epithelium, in which HCQ is highly enriched due to the tissue-specific affinity of HCQ, is considered to play important role in HCQ retinopathy. Herein, we used a metabolomics approach based on liquid chromatography-mass spectrometry to investigate the metabolic changes in retinal pigment epithelial cells (ARPE-19) with HCQ exposure at 6 h and 24 h. ARPE-19 cells were treated with HCQ at sub-lethal concentration 20 (IC 20), which was determined with MTT assay. Untargeted metabolic profiling revealed 9 and 15 metabolites that were significantly different between control group and HCQ exposure group at 6 h and 24 h, respectively. Enrichment and pathway analysis highlighted ascorbate and aldarate metabolism, d-Glutamine and d-glutamate metabolism and C5-Branched dibasic acid metabolism were disturbed after HCQ exposure. These findings increased our knowledge about the metabolic perturbation induced by HCQ exposure and indicated that metabolic profiling in the ARPE-19 cells might be helpful in understanding the mechanism of HCQ retinal toxicity and exploring potential biomarker.

Enzyme-Adsorbed Chitosan Nanogel Particles as Edible Pickering Interfacial Biocatalysts and Lipase-Responsive Phase Inversion of Emulsions.

Here, a simple food-grade Pickering emulsion system is prepared and adopted for biphasic biocatalytic reactions. The chitosan nanogels were prepared with strong dispersion of chitosan aggregates approaching neutral pH and then used as the particle emulsifiers to produce oil-in-water Pickering emulsions. The chitosan nanogel exhibited high affinity to negatively charged lipase. As a result of increasing the biphasic interfacial area and loading amount on the oil-water interface, the catalysis activity of lipase and recycling and pH stability were highly enhanced through colorimetric determination of p-nitrophenol (the hydrolysis product of p-nitrophenyl palmitate). A general strategy was proposed to obtain stimulus-responsive Pickering emulsions that can undergo phase inversion. The in situ modification of the wettability of chitosan nanogel could be attributed to the interaction between nanogel and free fatty acids, which was triggered by lipase hydrolysis. This would permit a rapid and controlled release of hydrophobic active components in response to enzymatic triggers.

Cyanidin-3-O-glucoside Protects Lens Epithelial Cells against High Glucose-Induced Apoptosis and Prevents Cataract Formation via Suppressing NF-κB Activation and Cox-2 Expression.

Diabetic cataract is one of the most important causes of blindness worldwide. Cyanidin-3-O-glucoside (C3G) is found to exert beneficial effects on many diabetic complications. However, its effect on diabetic cataract is not well known. Herein, we investigated the effect of C3G on high glucose-induced lens epithelial cell (SRA01/04) apoptosis and cataract formation as well as the involved mechanisms. We found C3G (20 µM) could preserve cell viability in SRA01/04 cells exposed to high glucose (100 µM). Meanwhile, C3G inhibited SRA01/04 cell apoptosis and regulated the Bcl-2/Bax ratio. Additionally, C3G suppressed NF-κB activation and subsequent cyclooxygenases-2 (Cox-2) expression, which are associated with the protection against apoptosis. Moreover, C3G attenuated lens opacity and protein aggregation in lens culture exposed to high glucose. In conclusion, C3G protected against high glucose-induced SRA01/04 cell apoptosis and cataract formation, which indicated the potential protection of anthocyanins on diabetic cataract.