[Vitamins and Immune System Health].

Keeping the immune system healthy forms an effective way to fight infections. Past experience has shown that, in addition to effective interventions including vaccination, drug therapy, and non-pharmaceutical intervention (NPI), dietary nutrition and mental health are also key factors in maintaining immune system health and combating emerging and sudden outbreaks of infections. As the main dietary nutrients, vitamins are active regulators of the immune response and exert a critical impact on the immunity of the human body. Vitamin deficiency causes increased levels of inflammation and decreased immunity, which usually starts in the oral tissues. Appropriate vitamin supplementation can help the body optimize immune function, enhance oral immunity, and reduce the negative impact of pathogen infection on the human body, which makes it a feasible, effective, and universally applicable anti-infection solution. This review focuses on the immunomodulatory effects of vitamin A, B, C, D, and E and proposes that an omics-based new systemic approach will lead to a breakthrough of the limitations in traditional single-factor single-pathway research and provide the direction for the basic and applied research of vitamin immune regulation and anti-infection in all aspects.

A composite consisting of bromine-doped carbon dots and ferric ions as a fluorescent probe for determination and intracellular imaging of phosphate.

A composite probe has been developed for fluorometric determination and imaging of phosphate in real water samples and in cells. The method is based on the use of weakly blue fluorescent bromine-doped carbon dots (C-dots) containing aromatic carbon-bromine groups and loaded with Fe3+ ions. The carboxy, phenolic hydroxy and aldehyde groups on the surface of the C-dots can coordinate with Fe3+ to form an adsorbed complex that reduces the blue fluorescence through an inner filter effect. If phosphate is added, it will capture Fe3+ on the surface of C-dots and restore fluorescence by ~88% via a displacement approach. The probe, best operated at excitation/emission maxima of 370/418 nm, has a linear response in the 0.4 to 22 µM phosphate concentration range and a 0.25 µM of detection limit. The relative standard deviation (at a phosphate level of 8.0 µM) is 3.6% (for n = 5). The method was applied to confocal imaging of phosphate in HeLa cells. Graphical abstractSchematic representation of the synthesis of bromine-doped carbon dots (C-dots) by a "one-step" approach. They are shown to be capable of (a) detecting phosphate in real water samples through the displacement approach, and (b) of imaging intracellular phosphate.

Identification of m6a-related signature genes in esophageal squamous cell carcinoma by machine learning method.

Background: We aimed to construct and validate the esophageal squamous cell carcinoma (ESCC)-related m6A regulators by means of machine leaning. Methods: We used ESCC RNA-seq data of 66 pairs of ESCC from West China Hospital of Sichuan University and the transcriptome data extracted from The Cancer Genome Atlas (TCGA)-ESCA database to find out the ESCC-related m6A regulators, during which, two machine learning approaches: RF (Random Forest) and SVM (Support Vector Machine) were employed to construct the model of ESCC-related m6A regulators. Calibration curves, clinical decision curves, and clinical impact curves (CIC) were used to evaluate the predictive ability and best-effort ability of the model. Finally, western blot and immunohistochemistry staining were used to assess the expression of prognostic ESCC-related m6A regulators. Results: 2 m6A regulators (YTHDF1 and HNRNPC) were found to be significantly increased in ESCC tissues after screening out through RF machine learning methods from our RNA-seq data and TCGA-ESCA database, respectively, and overlapping the results of the two clusters. A prognostic signature, consisting of YTHDF1 and HNRNPC, was constructed based on our RNA-seq data and validated on TCGA-ESCA database, which can serve as an independent prognostic predictor. Experimental validation including the western and immunohistochemistry staining were further successfully confirmed the results of bioinformatics analysis. Conclusion: We constructed prognostic ESCC-related m6A regulators and validated the model in clinical ESCC cohort as well as in ESCC tissues, which provides reasonable evidence and valuable resources for prognostic stratification and the study of potential targets for ESCC.

Simple and rapid detection of swine hepatitis E virus by reverse transcription loop-mediated isothermal amplification.

Hepatitis E virus (HEV) is an enteric pathogen of humans and animals, and pigs have been considered an important reservoir of this virus. Recent evidence has indicated the cross-species transmission of hepatitis E virus (HEV) from pigs to humans, causing zoonosis, mostly via consumption of uncooked or undercooked animal meat/viscera. In this study, we have developed a one-step RT-LAMP assay for rapid detection of swine HEV. Specific primer sets targeting the ORF3 gene were designed. The sensitivity of the RT-LAMP assay was 10(1) copies/µl of RNA template, which was tenfold higher than that of RT-nPCR. The specificity of this assay was demonstrated by the lack of amplification of DNA/RNA from other swine viruses. Furthermore, a total of 41 bile samples were subjected to RT-LAMP and RT-nPCR. Eighteen positive samples were detected by RT-nPCR, while 36 positive samples were detected by RT-LAMP, indicating that the sensitivity of the RT-LAMP assay was higher than that of the conventional RT-nPCR assay. The RT-LAMP assay reported here may be used for diagnosis of swine HEV, not only in laboratories but also under field conditions.

Lysosome-targetable brightly green fluorescence carbon dots for real-time monitoring in cell and highly efficient removal in environment of hypochlorite.

Due to the lacks of lysosome localization group and reaction/interaction site for hypochlorite (ClO-) on the surface of the carbon dots (C-dots), no C-dots-based lysosome-targeted fluorescence probes have, so far, been reported for real-time monitoring intracellular ClO-. In this work, 1,3,6-trinitropyrene (TNP) was used as a precursor to prepare C-dots with maximum excitation and emission wavelengths at 485 and 532 nm, respectively, and quantum yield âˆ¼ 27% by a hydrothermal approach at 196 °C for 6 h under a reductive atmosphere. The brightly green C-dots can sensitively and quickly respond to ClO- in aqueous solution through surface chemical reaction, showing a linear relationship in the range of 0.5-120 µΜ ClO- with 0.27 µΜ of limit of detection (LOD). Most significantly, the C-dots can localize at intracellular lysosome to image ClO- in lysosomes. Also, the magnetic nanocomposites (C-dots@Fe3O4 MNCs) were fabricated via a simple electrostatic self-assembly between Fe3O4 magnetic nanoparticles (Fe3O4 MNPs) and C-dots for highly efficient removal of ClO- in real samples. Therefore, lysosome-targetable C-dots-based probes for real-time monitoring ClO- were successfully constructed, opening up a promising door to investigate the biological functions and pathological roles of ClO- at organelle levels.

Effect of circumferential resection margin status on survival and recurrence in esophageal squamous cell carcinoma with neoadjuvant chemoradiotherapy.

Background: The aim of this study was to investigate whether circumferential resection margin (CRM) status has an impact on survival and recurrence in esophageal squamous cell carcinoma after neoadjuvant chemoradiotherapy. Methods: We screened patients with esophageal squamous cell carcinoma who underwent esophagectomy from January 2017 to December 2019. The CRM was reassessed. Patients were grouped into a CRM of 1 mm or less (0 < CRM ≤ 1 mm) and a CRM greater than 1 mm (CRM>1 mm). The impact of CRM on survival was investigated using Kaplan-Meier analysis and Cox regression modeling. The optimal CRM cut point was evaluated using restricted cubic spline curve. Results: A total of 89 patients were enrolled in this study. The CRM status was an independent risk factor for the prognosis (HR: 0.35, 95% CI: 0.16-0.73). Compared with a CRM of 1 mm or less, a CRM greater than 1 mm had better overall survival (HR: 0.35, 95% CI: 0.16-0.73, log-rank P = 0.011), longer disease-free survival (HR: 0.51, 95% CI: 0.27-0.95, log-rank P = 0.040), and less recurrence (HR: 0.44, 95% CI: 0.23-0.85, log-rank P = 0.015). We visualized the association between CRM and the hazard ratio of survival and identified the optimal cut point at 1 mm. Conclusions: A CRM greater than 1 mm had better survival and less recurrence compared to a CRM of 1 mm or less. A more radical resection with adequate CRM could benefit survival in patients with esophageal squamous cell carcinoma after neoadjuvant therapy.

Genetic characterization of H1N2 influenza a virus isolated from sick pigs in Southern China in 2010.

In China H3N2 and H1N1 swine influenza viruses have been circulating for many years. In January 2010, before swine were infected with foot and mouth disease in Guangdong, some pigs have shown flu-like symptoms: cough, sneeze, runny nose and fever. We collected the nasopharyngeal swab of all sick pigs as much as possible. One subtype H1N2 influenza viruses were isolated from the pig population. The complete genome of one isolate, designated A/swine/Guangdong/1/2010(H1N2), was sequenced and compared with sequences available in GenBank. The nucleotide sequences of all eight viral RNA segments were determined, and then phylogenetic analysis was performed using the neighbor-joining method. HA, NP, M and NS were shown to be closely to swine origin. PB2 and PA were close to avian origin, but NA and PB1were close to human origin. It is a result of a multiple reassortment event. In conclusion, our finding provides further evidence about the interspecies transmission of avian influenza viruses to pigs and emphasizes the importance of reinforcing swine influenza virus (SIV) surveillance, especially before the emergence of highly pathogenic FMDs in pigs in Guangdong.

Metabolism of novel anti-HIV agent 3-cyanomethyl-4-methyl-DCK by human liver microsomes and recombinant CYP enzymes.

AIM: To investigate the metabolism of 3-cyanomethyl-4-methyl-DCK (CMDCK), a novel anti-HIV agent, by human liver microsomes (HLMs) and recombinant cytochrome P450 enzymes (CYPs). METHODS: CMDCK was incubated with HLMs or a panel of recombinant cytochrome P450 enzymes including CYP1A2, 2B6, 2C8, 2C9, 2C19, 2D6, 3A4, and 3A5. LC-ion trap mass spectrometry was used to separate and identify CMDCK metabolites. In the experiments with recombinant cytochrome P450 enzymes, specific chemical inhibitors combined with CYP antibodies were used to identify the CYP isoforms involved in CMDCK metabolism. RESULTS: CMDCK was rapidly and extensively metabolized by HLMs. Its intrinsic hepatic clearance estimated from the in vitro data was 19.4 mL·min(-1)·kg(-1), which was comparable to the mean human hepatic blood flow rate (20.7 mL·min(-1)·kg(-1)). The major metabolic pathway of CMDCK was oxidation, and a total of 14 metabolites were detected. CYP3A4 and 3A5 were found to be the principal CYP enzymes responsible for CMDCK metabolism. CONCLUSION: CMDCK was metabolized rapidly and extensively in human hepatic microsomes to form a number of oxidative metabolites. CYP3A4 and 3A5 were the predominant enzymes responsible for the oxidation of CMDCK.

[Metabolism of 3-cyanomethyl-4-methyl-DCK, a new anti-HIV candidate, in human intestinal microsomes].

The biotransformation, CYP reaction phenotyping, the impact of CYP inhibitors and enzyme kinetics of 3-cyanomethyl-4-methyl-DCK (CMDCK), a new anti-HIV preclinical candidate belonging to DCK analogs, were investigated in human intestinal microsomes and recombinant cytochrome P450 (CYP) enzymes. CMDCK (4 micromol L(-1)) was incubated with a panel of rCYP enzymes (CYP1A2, 2C9, 2C19, 2D6 and 3A4) in vitro. The remaining parent drug in incubates was quantitatively analyzed by a LC-MS method. CYP3A4 was identified as the principal CYP isoenzyme responsible for its metabolism in intestinal microsomes. The major metabolic pathway of CMDCK was oxidation and a number of oxidative metabolites were screened with LC-MS. The Km, Vmax, CLint and T1/2 of CMDCK obtained from human intestinal microsome were 45.6 micromol L(-1), 0.33 micromol L(-1) min(-1), 12.1 mL min(-1) kg(-1) and 25.7 min, respectively. Intestinal clearance of CMDCK was estimated from in vitro data to be 3.3 mL min(-1) kg(-1), and was almost equal to the intestinal blood flow rate (4.6 mL min(-1) kg(-1)). The selective CYP3A4 inhibitors, ketoconazole, troleandomycin and ritonavir demonstrated significant inhibitory effects on CMDCK intestinal metabolism, which suggested that co-administration of CMDCK with potent CYP3A inhibitors, such as ritonavir, might decrease its intestinal metabolic clearance and subsequently improve its bioavailability in body.

Biofilm Production Ability, Virulence and Antimicrobial Resistance Genes in Staphylococcus aureus from Various Veterinary Hospitals.

: Staphylococcus aureus (S. aureus) is one of the most clinically important zoonotic pathogens, but an understanding of the prevalence, biofilm formulation ability, virulence, and antimicrobial resistance genes of S. aureus from veterinary hospitals is lacking. By characterizing S. aureus in different origins of veterinary hospitals in Guangzhou, China, in 2019, we identified with the presence of S. aureus in pets (17.1%), veterinarians (31.7%), airborne dust (19.1%), environmental surfaces (4.3%), and medical device surfaces (10.8%). Multilocus sequence typing (MLST) and Staphylococcus protein A (spa) typing analyses demonstrated methicillin-sensitive S. aureus (MSSA) ST398-t571, MSSA ST188-t189, and methicillin-resistant S. aureus (MRSA) ST59-t437 were the most prevalent lineage. S. aureus with similar pulsed-field gel electrophoresis (PFGE) types distributed widely in different kinds of samples. The crystal violet straining assays revealed 100% (3/3) of MRSA ST59 and 81.8% (9/11) of MSSA ST188 showed strong biofilm formulation ability, whereas other STs (ST1, ST5, ST7, ST15, ST88, ST398, ST3154 and ST5353) showed weak biofilm production ability. Polymerase chain reaction (PCR) confirmed the most prevalent leucocidin, staphylococcal enterotoxins, ica operon, and adhesion genes were lukD-lukE (49.0%), sec-sel (15.7%), icaA-icaB-icaC-icaR (100.0%), and fnbB-cidA-fib-ebps-eno (100.0%), respectively. Our study showed that the isolates with strong biofilm production ability had a higher prevalence in clfA, clfB, fnbA and sdrC genes compared to the isolates with weak biofilm production ability. Furthermore, 2 ST1-MRSA isolates with tst gene and 1 ST88-MSSA isolate with lukS/F-PV gene were detected. In conclusion, the clonal dissemination of S. aureus of different origins in veterinary hospitals may have occurred; the biofilm production capacity of S. aureus is strongly correlated with ST types; some adhesion genes such as clfA, clfB, fnbA, and sdrC may pose an influence on biofilm production ability and the emergence of lukS/F-PV and tst genes in S. aureus from veterinary hospitals should raise our vigilance.

Dinuclear magnesium, zinc and aluminum complexes supported by bis(iminopyrrolide) ligands: synthesis, structures, and catalysis toward the ring-opening polymerization of ε-caprolactone and rac-lactide.

Synthesis and characterization of novel dinuclear magnesium, zinc and aluminum complexes supported by bis(iminopyrrolide) ligands and their catalysis toward the ring-opening polymerization (ROP) of ε-caprolactone (ε-CL) and rac-lactide (rac-LA) were carried out. The ligand precursors [(5-Bu(t)-2-C4H2NH)CH=N(CH2)2]2NH (H2L(Bu), 1) and [(2-C4H3NH)CH=N(CH2)2]2NH (H2L(H), 2) were prepared by condensation of diethylene triamine with 5-tert-butyl-1H-pyrrole-2-carbaldehyde and 1H-pyrrole-2-carbaldehyde, respectively. Treatment of 1 with 2 equiv. of Bu(n)MgOBn in toluene at 70 °C produced dinuclear magnesium complex [(µ-OBn)2Mg2L(Bu)] (3). Similar treatment of 1 with EtZnOBn generated [(µ-OBn)2Zn2L(Bu)] (4). Reaction of 2 with 2 equiv. of Me2AlOBn in toluene at 70 °C afforded aluminum complex [Me2Al(µ-OBn)2AlL(H)] (5). Complexes 3-5 were characterized by (1)H and (13)C NMR spectroscopy, elemental analyses, and single crystal X-ray diffraction techniques. Each of complexes 3-5 is active for the ROP of ε-CL and rac-LA. Kinetic studies of the polymerization reactions were performed.

Synthesis of N,N,O-chelate zinc and aluminum complexes and their catalysis in the ring-opening polymerization of ε-caprolactone and rac-lactide.

Zinc and aluminum complexes supported by N,N,O-chelate ligands were synthesized and characterized. The zinc complexes [Zn(Et){2-{OC(R(1))=CH}-6-(3,5-Me2C3HN2)C5H3N}]2 (R(1) = Ph, 1a; R(1) = Bu(t), 1b) were synthesized by reaction of ligand precursors 2-{R(1)C(O)CH2}-6-(3,5-Me2C3HN2)C5H3N (R(1) = Ph, HL(1); R(1) = Bu(t), HL(2)) with ZnEt2. The aluminum complexes [Al(R)2{2-{OC(Ph)=CH}-6-(3,5-Me2C3HN2)C5H3N}] (R = Me, 2a; R = Et, 2b) were synthesized by reaction of HL(1) with AlMe3 or AlEt3. Similar treatment of the ligand precursor 2-{Ph2C(OH)CH2}-6-(3,5-Me2C3HN2)C5H3N (HL(3)) with AlMe3 or AlEt3 afforded aluminum complexes [Al(R)2{2-{OC(Ph)2CH2}-6-(3,5-Me2C3HN2)C5H3N}] (R = Me, 3a; R = Et, 3b). The complexes were characterized by (1)H and (13)C{(1)H} NMR spectroscopy, elemental analyses and single crystal X-ray diffraction (for 1a, 1b, 2b and 3a). All the complexes are active to catalyze the ring-opening polymerization of ε-caprolactone in the presence of BnOH, leading to polycaprolactone with good molecular weight control and relatively narrow molecular weight distribution. The zinc complexes/BnOH showed good catalytic activity for the ring-opening polymerization of rac-lactide, displaying good molecular weight control and very narrow molecular weight distributions. The PLA catalyzed by complex 1a/BnOH showed somewhat hetero-stereoselectivity with Pr up to 0.73 when the polymerization was performed in THF at 0 °C. Complex 1a/BnOH also catalyzed block copolymerization of ε-CL and rac-LA with good molecular weight control of the polymer. Kinetic studies of the polymerization reactions were performed.

Isolation and Phylogenetic Analysis of H1N1 Swine Influenza Virus from Sick Pigs in Southern China.

Two swine influenza (SI) H1N1 virus was isolated from a pig during a severe outbreak of respiratory disease in south China. The two H1N1 influenza viruses were classical SI virus. A/swine/Guangdong/L6/09 is classical SI virus of recent years, which is of the main SI virus in China. Howere, A/swine/Guangdong/L3/09 was closet to A/swine/Iowa/1931, which was the first isolated SI virus and had demonstrated significant pathogenicity in animal models. The results of phylogenetic analysis of A/swine/Guangdong/L3/09 showed a close relationship with the 1918 pandemic virus. The results suggested that the previous SI virus appeared again. Whether, it brought a new pandemic to pigs deserves more attention.