Electrospun Fiber Membrane with the Dual Affinity of Chelation and Covalent Interactions for the Efficient Enrichment of Glycoproteins.

As important biomarkers of many diseases, glycoproteins are of great significance to biomedical science. It is essential to develop efficient glycoprotein enrichment platforms and investigate their adsorption mechanism. In this work, a conspicuous enrichment strategy for glycoproteins was developed by using an electrospun fiber membrane wrapped with polydopamine (PDA) and modified with 3-aminophenylboronic acid and nickel ions, named PAN/DA@PDA@APBA/Ni. The enrichment characteristics of PAN/DA@PDA@APBA/Ni toward glycoproteins were explored through adsorption behavior. Thanks to the existence of two sites of interaction (metal ion chelation and boronate affinity), PAN/DA@PDA@APBA/Ni exhibited significant enrichment capacity for glycoproteins, ovalbumin (604.6 mg/g), and human immunoglobulin G (331.0 mg/g). The adsorption kinetic results of glycoprotein ovalbumin on PAN/DA@PDA@APBA/Ni conform to the pseudo-first-order kinetic model in the first adsorption stage, while the second half adsorption stage is more in line with the pseudo-second-order kinetic model. Moreover, the physical characteristics of PAN/DA@PDA@APBA/Ni and subsequent adsorption experiments on electrospun fiber modified with only phenylboronic acid or nickel ions both confirmed two sites of interaction (metal ion chelation and boronate affinity, respectively). Furthermore, a stepwise elution method with dual-affinity interaction was designed and successfully applied to enrich glycoproteins in real biological samples. This work provides an idea for sample pretreatment, especially for the design of dual-affinity materials in glycoproteins enrichment.

Effects of sulfate on the photosynthetic physiology characteristics of Hydrocotyle vulgaris under zinc stress.

The effects of sulfate on the zinc (Zn) bioaccumulation characteristics and photophysiological mechanisms of the ornamental plant Hydrocotyle vulgaris were explored using a hydroponic culture under three Zn concentrations (300, 500 and 700mgL-1 ) with (400µmolL-1 ) or without the addition of sulfate. Results showed that: (1) tissue Zn concentrations and total Zn contents increased with increasing hydroponic culture Zn concentrations; and sulfate addition decreased Zn uptake and translocation from roots to shoots; (2) Zn exposure decreased photosynthetic pigment synthesis, while sulfate changed this phenomenon, especially for chlorophyll a under 300mgL-1 Zn treatment; (3) Zn exposure decreased photosynthetic function, while sulfate had positive effects, especially on the photosynthetic rate (Pn ) and stomatal conductance (Gs ); and (4) chlorophyll fluorescence parameters related to light energy capture, transfer and assimilation were generally downregulated under Zn stress, while sulfate had a positive effect on these processes. Furthermore, compared to photosynthetic pigment synthesis and photosynthesis, chlorophyll fluorescence was more responsive, especially under 300mgL-1 Zn treatment with sulfate addition. In general, Zn stress affected photophysiological processes at different levels, while sulfate decreased Zn uptake, translocation, and bioaccumulation and showed a positive function in alleviating Zn stress, ultimately resulting in plant growth promotion. All of these results provide a theoretical reference for combining H. vulgaris with sulfate application in the bioremediation of Zn-contaminated environments at the photophysiological level.

Biodegradation characteristics and mechanism of terbuthylazine by the newly isolated Agrobacterium rhizogenes strain AT13.

Terbuthylazine (TBA) is an emerging environmental contaminant that poses moderate to high risk to non-target organisms. In this study, a newly TBA-degrading strain, Agrobacterium rhizogenes AT13, was isolated. This bacterium degraded 98.7% of TBA (100 mg/L) within 39 h. Based on the six detected metabolites, three novel pathways of strain AT13, including dealkylation, deamination-hydroxylation, and ring-opening reactions, were proposed. The risk assessment demonstrated that most degradation products might be substantially less harmful than TBA. Whole-genome sequencing and RT-qPCR analysis revealed that ttzA, which encodes S-adenosylhomocysteine deaminase (TtzA), is closely related to TBA degradation in AT13. Recombinant TtzA showed 75.3% degradation of 50 mg/L of TBA within 13 h and presented a Km value of 0.299 mmol/L and a Vmax value of 0.041 mmol/L/min. The molecular docking results indicated that the binding energy of TtzA to TBA was -32.9 kcal/mol and TtzA residue ASP161 formed two hydrogen bonds with TBA at distances of 2.23 and 1.80 Å. Moreover, AT13 efficiently degraded TBA in water and soil. Overall, this study provides a foundation for the characterization and mechanism of TBA biodegradation and may enhance our understanding of the TBA biodegradation by microbes.

Microbial degradation of petroleum characteristic pollutants in hypersaline environment, emphasizing n-hexadecane and 2,4 di-tert-butylphenol.

In this paper, nine strains of salt-tolerant petroleum-degrading bacteria were applied to an biological aerated filter. Simulating the degradation of high-salinity petroleum wastewater with n-hexadecane and 2,4-ditert-butylphenol as the primary pollutants and analyzing the structure of the biofilm at various salt concentrations. According to the results, when the salinity was 4%, the COD removal efficiency reached 74.34%. Various halotolerant microorganisms have adapted to various salt concentrations. At a salinity of 3%, n-hexadecane exhibited the best degradation effect, with a rate of 83.21%. Shewanella, Acinetobacter, and Marinobacter were the predominant bacterial groups at the time. At 4% salinity, Acinetobacter and Pseudomonas were the predominant bacteria, and the average 2,4-ditert-butylphenol degradation rate was the highest at 63.02%. This study provided an experimental basis for further studying the biological treatment of high-salinity petroleum wastewater.

Upregulation of LRRC8A by m5C modification-mediated mRNA stability suppresses apoptosis and facilitates tumorigenesis in cervical cancer.

Cervical cancer (CC) is one of the most common gynecological malignancies with poor prognosis for advanced CC patients. LRRC8A is a volume-regulated anion channel protein involved in cellular homeostasis, but its role in CC remains largely unknown. In this study, we found that LRRC8A is elevated in CC and associated with poor prognosis. LRRC8A maintains cell survivals under the hypotonic condition, and promotes tumorigenesis through apoptosis suppression in vitro and in vivo. Notably, LRRC8A is upregulated by NSUN2-mediated m5C modification. m5C modified-LRRC8A mRNA is bound by the RNA binding protein YBX1 followed by the increased RNA stability. Moreover, loss of NSUN2 suppresses the proliferation and metastasis of CC cells, and NSUN2 expression is positively correlated with LRRC8A expression in CC. Altogether, our study demonstrates that the NSUN2-m5C-LRRC8A axis is crucial and would be a potential therapeutic target for CC.

Fosthiazate exposure induces oxidative stress, nerve damage, and reproductive disorders in nontarget nematodes.

As a forceful nematicide, fosthiazate has been largely applied in the management of root-knot nematodes and other herbivorous nematodes. However, the toxicity of fosthiazate to nontarget nematodes is unclear. To explore the toxicity and the mechanisms of fosthiazate in nontarget nematodes, Caenorhabditis elegans was exposed to 0.01-10 mg/L fosthiazate. The results implied that treatment with fosthiazate at doses above 0.01 mg/L could cause injury to the growth, locomotion behavior, and reproduction of the nematodes. Moreover, L1 larvae were more vulnerable to fosthiazate exposure than L4 larvae. Reactive oxygen species (ROS) production and lipofuscin accumulation were fairly increased in 1 mg/L fosthiazate-exposed nematodes. Treatment with 0.1 mg/L fosthiazate significantly inhibited the activity of acetylcholinesterase (p < 0.01). Furthermore, subacute exposure to 10 mg/L fosthiazate strongly influenced the expression of genes related to oxidative stress, reproduction, and nerve function (e.g., gst-1, sod-1, puf-8, wee-1.3, and ace-1 genes). These findings suggested that oxidative stress, reproduction and nerve disorders could serve as key endpoints of toxicity induced by fosthiazate. The cyp-35a family gene was the main metabolic fosthiazate in C. elegans, and the cyp-35a5 subtype was the most sensitive, with a change in expression level of 2.11-fold compared with the control. These results indicate that oxidative stress and neurological and reproductive disorders played fundamental roles in the toxicity of fosthiazate in C. elegans and may affect the abundance and function of soil nematodes.

Novel Stereoselective Syntheses of (+)-Streptol and (-)-1-epi-Streptol Starting from Naturally Abundant (-)-Shikimic Acid.

Novel highly stereoselective syntheses of (+)-streptol and (-)-1-epi-streptol starting from naturally abundant (-)-shikimic acid were described in this article. (-)-Shikimic acid was first converted to the common key intermediate by 11 steps in 40% yield. It was then converted to (+)-streptol by three steps in 72% yield, and it was also converted to (-)-1-epi-streptol by one step in 90% yield. In summary, (+)-streptol and (-)-1-epi-streptol were synthesized from (-)-shikimic acid by 14 and 12 steps in 29 and 36% overall yields, respectively.

Evaluation of exploitive potential for higher bioactivity and lower residue risk enantiomer of chiral fungicide pydiflumetofen.

BACKGROUND: Pydiflumetofen, as a new succinate dehydrogenase inhibitor (SDHI) chiral fungicide, has been used in crop production because of its broad-spectrum and high-efficiency antifungal activity. However, little is known about pydiflumetofen at the chiral level. The stereoselective bioactivity and degradation of pydiflumetofen enantiomers were therefore investigated. RESULTS: Pydiflumetofen presented effective bioactivity against the eight tested phytopathogens, and its enantiomers showed significant differences in activity. The bioactivity of R-pydiflumetofen was 9.0-958.8 times higher than that of the S enantiomer. Treatment with R-pydiflumetofen increased the cell membrane permeability of Sclerotinia sclerotiorum and decreased exopolysaccharide and oxalic acid production more than treatment with S-pydiflumetofen. Furthermore, R-pydflumetofen exhibited better inhibitory activity against the succinate dehydrogenase enzyme of S. sclerotiorum than S-pydiflumetofen by 584-fold. According to homology modeling and molecular docking studies, the binding affinities of the R and S enantiomers were -7.0 and -5.3 kcal mol-1 , respectively. Additionally, the degradation half-lives of S- and R-pydiflumetofen in three vegetables (cucumber, eggplant, and cowpea) under field conditions were 2.56-3.12 days and 2.48-2.76 days, respectively, which reveals that R-pydiflumetofen degrades faster than S-pydiflumetofen. CONCLUSION: Based on the results obtained, R-pydiflumetofen not only exhibited a higher bactericidal activity, but also posed fewer residual risks in the environment. The mechanism of the stereoselective bioactivity was correlated with the stereoselective inhibition activity of the target enzyme and affected the cell membrane permeability and the production of exopolysaccharide and oxalic acid. This research could provide a foundation for the systematic evaluation of pydiflumetofen from an enantiomeric view. © 2021 Society of Chemical Industry.

Stereostructure-activity mechanism of cyproconazole by cytochrome P450 in rat liver microsomes: A combined experimental and computational study.

Cyproconazole (CPZ), representing the chiral triazole fungicides, is widely used in the pharmaceutical and agricultural fields. To clarify its potential adverse effects on the generalized CYP-mediated processes within mammalian, a comparative experimental and computational approach was employed to investigate the CYP-mediated metabolism processes of CPZ stereoisomers in rat liver microsomes (RLMs). The depletion rate of CPZ stereoisomers in vitro incubation system with RLMs followed the order RR-> SS-> SR-> RS-CPZ. The results of kinetic assays were in line with the depletion rate results. Further inhibition assay confirmed the stereoselective metabolism of CPZ stereoisomers by different CYP isoforms. Molecular dynamics (MD) simulation revealed the stereoselective metabolism mechanism. Several hydrogen bonds and π-stacking restrict the position of CPZ isomers in the active cavity of CYPs so that the 4'-nitrogen on the triazole ring can bind closely to the heme of CYP, which results in the metabolism of CPZ isomers. By combining the computational and experimental approaches, the structure-activity relationship of CPZ and CYP was elucidated, and this method can be further applied to predict the degree of uncertainty in the process of xenobiotic biotransformation of triazole fungicides and serve as a basis for risk assessment.

Enantioseparation and stereoselective dissipation of the novel chiral fungicide pydiflumetofen by ultra-high-performance liquid chromatography tandem mass spectrometry.

Pydiflumetofen is a novel and efficient broad-spectrum chiral fungicide consisting of a pair of enantiomers. A simple and sensitive chiral analytical method was established to determine the enantiomers of this chiral fungicide in food and environmental samples by ultra-high-performance liquid chromatography tandem triple quadrupole mass spectrometry (UHPLC-MS/MS) using QuEChERS method coupled with octadecylsilane-dispersive solid-phase extraction (C18-dSPE) as extraction procedure. The specific optical rotation and the absolute configuration of the enantiomers were identified by polarimetry and electronic circular dichroism (ECD). The elution order of the pydiflumetofen enantiomers on Lux Cellulose-2 was S-(-)-pydiflumetofen and R-(+)-pydiflumetofen. The average recoveries of eleven matrices ranged from 71.3% to 107.4%. The intraday relative standard deviations (RSDs) were less than 11.8%, and the interday RSDs were less than 12.6% for the two enantiomers. Stereoselective dissipation in pakchoi and soil were observed: S-(-)-pydiflumetofen was degraded faster than R-(+)-pydiflumetofen in pakchoi, causing the enantiomer fraction (EF) of the enantiomers to change from 0.50 to 0.42 in 7 days. However, R-(+)-pydiflumetofen was degraded faster than S-(-)-pydiflumetofen in soil, causing the EF of the enantiomers to change from 0.49 to 0.52 in 21 days. This study provides a method for monitoring pydiflumetofen enantiomer residues, which is crucial for improving risk assessments and the development of chiral pesticides.

Efficient and Highly Stereoselective Syntheses of (+)-proto-Quercitol and (-)-gala-Quercitol Starting from the Naturally Abundant (-)-Shikimic Acid.

Efficient and highly stereoselective syntheses of (+)-proto-quercitol and (-)-gala-quercitol starting from the naturally abundant (-)-shikimic acid were described in this article. (-)-Shikimic acid was first converted to the key intermediate by eight steps in 53% yield. It was then converted to (+)-proto-quercitol by three steps in 78% yield and was also converted to (-)-gala-quercitol by five steps in 63% yield. In summary, (+)-proto-quercitol and (-)-gala-quercitol were synthesized from (-)-shikimic acid by 11 and 13 steps in 41 and 33% overall yields, respectively.

Novel stereoselective syntheses of N-octyl-ß-valienamine (NOV) and N-octyl-4-epi-ß-valienamine (NOEV) from (-)-shikimic acid.

N-Octyl-ß-valienamine (NOV) 1 and N-octyl-4-epi-ß-valienamine (NOEV) 2 are potent chemical chaperone drug candidates for the therapy of lysosomal storage disorders. Novel stereoselective syntheses of NOV 1 and NOEV 2 starting from naturally abundant (-)-shikimic acid are described in this article. The common key intermediate compound 5 was first synthesized from readily available (-)-shikimic acid via 9 steps in 50% yield. Compound 5 was then converted to NOV 1via 5 steps in 61% yield, and it was also converted to NOEV 2via 8 steps in 38% yield. In summary, NOV 1 was synthesized via 14 steps in 31% overall yield; and NOEV 2 was synthesized via 17 steps in 19% overall yield.

Activation of ß-adrenergic receptor promotes cellular proliferation in human glioblastoma.

Glioblastoma multiforme is the most common and aggressive form of primary malignant brain tumor. Previous evidence demonstrates that ß-adrenergic receptors (ß-ARs) are closely associated with the occurrence and development of brain tumors. However, the functional role of ß-ARs in human glioblastoma and the underlying mechanisms are not fully understood. In the present study, by using the MTT assay, western blotting, and the reverse transcription polymerase chain reaction, it was revealed that isoproterenol (ISO), an agonist of ß-ARs, promoted the proliferation of U251 cells but not U87-MG cells, and that this effect was blocked by the ß-ARs antagonist propranolol. It was also demonstrated that ISO transiently induced extracellular signal-related kinase 1/2 (ERK1/2) phosphorylation, and that blocking the mitogen-activated protein kinase pathway by U0126 inhibited ERK1/2 phosphorylation and suppressed U251 cell proliferation. In addition, ß-ARs activation increased the expression of matrix metalloproteinase (MMP) family members MMP-2 and MMP-9 mRNA through ERK1/2 activation. In conclusion, these data suggest that ß-ARs induce ERK1/2 phosphorylation, which may in turn increase MMPs expression to promote U251 cell proliferation. These results provide additional insight into the specific roles of ß-ARs in glioblastoma.

[Genetic and prenatal diagnosis for a haemophilia A family with two novel mutations of F8 gene].

OBJECTIVE: To conduct genetic diagnosis for a family affected with hamophilia A. METHODS: Potential mutations of the F8 gene were analyzed with PCR and Sanger sequencing. Carriers of the mutation were identified through linkage analysis using short tandem repeat (STR) markers. Suspected mutations were verified among 100 healthy controls to rule out genetic polymorphism. Prenatal diagnosis was provided based on the above results. RESULTS: Sequencing analysis has identified two mutations, c.1 A>T and c.4 C>T, which have replaced the start codon (ATG) with leucine (TTG) and glutamine (GAA) with the stop codon (TAA), respectively. The same mutations were not found among the 100 healthy controls. The patient's mother and sister were heterozygous for the same mutations. Upon prenatal diagnosis, the fetus was determined as a male and did not harbor the above mutations. Linkage analysis also confirmed that the fetus has inherited the non-risk X chromosome from his maternal grandfather. CONCLUSION: Detection of pathogenic mutations can enable prenatal diagnosis for the disease.

[Application of array comparative genomic hybridization in prenatal diagnosis of a case with 5q35 deletion syndrome].

OBJECTIVE: To use combined G-banding and array-comparative genomic hybridization (aCGH) for the prenatal diagnosis of a fetus with 5q35 deletion syndrome. METHODS: Chromosomal karotypes of the fetus and parents were analyzed with G-banding analysis. aCGH was performed to detect minor chromosomal structural abnormalities. RESULTS: The karyotype of the fetus was ascertained as 46, XY, t(5;10)(q35;p13), and the karyotypes of the parents were normal. aCGH has identified a de novo 1.68 Mb deletion at 5q35.2q35.3 and a 1.44 Mb duplication at 10p14p13. CONCLUSION: aCGH has a higher resolution and greater accuracy for mapping chromosomal aberrations and is a useful supplement for G banding karyptyping analysis.

ß2-adrenergic receptor activation promotes the proliferation of A549 lung cancer cells via the ERK1/2/CREB pathway.

Lung cancer is one of the most common cancers worldwide and accounts for 28% of all cancer-related deaths. The expression of the ß2­adrenergic receptor (ß2­AR), one of the stress­inducible receptors, has been reported to be closely correlated with malignant tumors. However, the role of ß2­AR activation in human lung epithelial­derived cancer A549 cells and the underlying mechanisms are not fully understood. In the present study, we found that activation of ß2­AR but not ß1­AR promoted the proliferation of A549 cells. Isoproterenol (ISO) stimulation of ß2­AR induced extracellular signal­regulated kinase 1/2 (ERK1/2) and cyclic adenosine monophosphate response element­binding protein (CREB) phosphorylation. Blocking the ERK1/2 pathway by U0126 inhibited CREB phosphorylation and also suppressed A549 cell proliferation. Moreover, ISO treatment enhanced the expression of matrix metalloproteinase (MMP) family proteins such as MMP­2, MMP­9, and also vascular endothelial growth factor (VEGF), which were able to be blocked by knockdown of CREB. In conclusion, our data revealed that ß2­AR induced ERK1/2 phosphorylation which in turn activated CREB to promote A549 cell proliferation. These findings elucidate potential therapeutic targets for lung cancer treatment.