[Population structure of food-borne Staphylococcus aureus in China].

Objective: To understand the population structure of food-borne Staphylococcus (S.) aureus in China. Methods: Whole genome sequencing was used to analyze 763 food-borne S. aureus strains from 16 provinces in China from 2006 to 2020. Multilocus sequence typing (MLST), staphylococcal protein A gene (spa) typing, and staphylococcal chromosome cassettemec (SCCmec) typing were conducted, and minimum spanning tree based on ST types (STs) was constructed by BioNumerics 7.5 software. Thirty-one S. aureus strains isolated from imported food products were also included in constructing the genome phylogenetic tree. Results: A total of 90 STs (20 novel types) and 160 spa types were detected in the 763 S. aureus isolates. The 72 STs (72/90, 80.0%) were related to 22 clone complexes. The predominant clone complexes were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, accounting for 82.44% (629/763) of the total. The STs and spa types in the predominant clone complexes changed over the years. The methicillin-resistant S. aureus (MRSA) detection rate was 7.60%, and 7 SCCmec types were identified. The ST59-t437-Ⅳa (17.24%, 10/58), ST239-t030-Ⅲ (12.07%, 7/58), ST59-t437-Ⅴb (8.62%, 5/58), ST338-t437-Ⅴb (6.90%, 4/58) and ST338-t441-Ⅴb (6.90%, 4/58) were the main types in MRSA strains. The genome phylogenetic tree had two clades, and the strains with the same CC, ST, and spa types clustered together. All CC7 methicillin sensitive S. aureus strains were included in Clade1, while 21 clone complexes and all MRSA strains were in Clade2. The MRSA strains clustered according to the SCCmec and STs. The strains from imported food products in CC398, CC7, CC30, CC12, and CC188 had far distances from Chinese strains in the tree. Conclusions: In this study, the predominant clone complexes of food-borne strains were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, which overlapped with the previously reported clone complexes of hospital and community-associated strains in China, suggesting that close attention needs to be paid to food, a vehicle of pathogen transmission in community and food poisoning.

[Prediction of superantigen active sites and clonal expression of staphylococcal enterotoxin-like W].

Objective: The docking and superantigen activity sites of staphylococcal enterotoxin-like W (SElW) and T cell receptor (TCR) were predicted, and its SElW was cloned, expressed and purified. Methods: AlphaFold was used to predict the 3D structure of SElW protein monomers, and the protein models were evaluated with the help of the SAVES online server from ERRAT, Ramachandran plot, and Verify_3D. The ZDOCK server simulates the docking conformation of SElW and TCR, and the amino acid sequences of SElW and other serotype enterotoxins were aligned. The primers were designed to amplify selw, and the fragment was recombined into the pMD18-T vector and sequenced. Then recombinant plasmid pMD18-T was digested with BamHⅠand Hind Ⅲ. The target fragment was recombined into the expression plasmid pET-28a(+). After identification of the recombinant plasmid, the protein expression was induced by isopropyl-beta-D- thiogalactopyranoside. The SElW expressed in the supernatant was purified by affinity chromatography and quantified by the BCA method. Results: The predicted three-dimensional structure showed that the SElW protein was composed of two domains, the amino-terminal and the carboxy-terminal. The amino-terminal domain was composed of 3 α-helices and 6 ß-sheets, and the carboxy-terminal domain included 2 α-helices and 7 antiparallel ß-sheets composition. The overall quality factor score of the SElW protein model was 98.08, with 93.24% of the amino acids having a Verify_3D score ≥0.2 and no amino acids located in disallowed regions. The docking conformation with the highest score (1 521.328) was selected as the analysis object, and the 19 hydrogen bonds between the corresponding amino acid residues of SElW and TCR were analyzed by PyMOL. Combined with sequence alignment and the published data, this study predicted and found five important superantigen active sites, namely Y18, N19, W55, C88, and C98. The highly purified soluble recombinant protein SElW was obtained with cloning, expression, and protein purification. Conclusions: The study found five superantigen active sites in SElW protein that need special attention and successfully constructed and expressed the SElW protein, which laid the foundation for further exploration of the immune recognition mechanism of SElW.

Autonomous atmospheric water seeping MOF matrix.

The atmosphere contains an abundance of fresh water, but this resource has yet to be harvested efficiently. To date, passive atmospheric water sorbents have required a desorption step that relies on steady solar irradiation. Since the availability and intensity of solar radiation vary, these limit on-demand desorption and hence the amount of harvestable water. Here, we report a polymer-metal-organic framework that provides simultaneous and uninterrupted sorption and release of atmospheric water. The adaptable nature of the hydro-active polymer, and its hybridization with a metal-organic framework, enables enhanced sorption kinetics, water uptake, and spontaneous water oozing. We demonstrate continuous water delivery for 1440 hours, producing 6 g of fresh water per gram of sorbent at 90% relative humidity (RH) per day without active condensation. This leads to a total liquid delivery efficiency of 95% and an autonomous liquid delivery efficiency of 71%, the record among reported atmospheric water harvesters.

[Cloning and expression of recombinant truncated SElX protein and evaluation on the related emetic activities].

Objective: To analyze the amino acid polymorphism of truncated Staphylococcal enterotoxin-like toxin X (tSElX), and to evaluate its related emetic activities. Methods: Sequence of tselx was compared with both the genome sequence of 145 CC398 strains completed in our research group and the NCBI database. Primers were designed to amplify the target gene of tselx, and the fragment was recombined into pMD18-T vector and sequenced. PCR product was digested with BamHⅠ and EcoRⅠ, and constructed into plasmid pGEX-6P-1 and pET-28a (+). After recombinant plasmid was identified, the protein expression was induced by IPTG. Proteins expressed in the form of inclusion bodies were denatured and renatured, then purified by affinity chromatography and ultrafiltration. Purified tSElX protein was then fed to common marmosets with the dose of 250 µg/kg to observe the vomiting reaction. Results: tselx gene was present in 145 strains of CC398 strains from the different origins (patients, healthy people and animals) in China. Homology of the amino acid sequence of the protein from the Chinese strains appeared 100.0%, while the homology with the four American strains were 97.8%(1) and 98.9%(3), respectively. Through two sets of expression systems and different induction conditions, tSElX was expressed in the form of inclusion bodies. The high purity soluble recombinant tSElX was thus obtained by denaturated and renaturated processes. At the dose of 250 µg/kg, tSElX protein did not cause vomiting in common marmosets. Conclusions: Results of this study showed that the amino acid sequence of tSElX was highly conserved and was universally present in a particular clone group. We obtained soluble recombinant tSElX protein with high purity. We also noticed that tSElX did not have the animal emetic activity at a dose of 250 µg/kg.

MiR-16 inhibits hepatocellular carcinoma progression by targeting FEAT through NF-κB signaling pathway.

OBJECTIVE: MicroRNA-16 (miR-16) expression has been proved to take part in the initiation and development of several cancers, including hepatocellular carcinoma (HCC). However, its role and its molecular mechanism in HCC cells remain unclear. Our study aimed to elucidate miR-16 probable role and potential mechanism in HCC cells. PATIENTS AND METHODS: MiR-16 expression in HCC was measured by Real Time-Polymerase Chain Reaction (RT-PCR). MiR-16 mimic or inhibitor was applied to increase or decrease miR-16 expression in Huh7 cells separately. The cell viability was measured by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide). The invaded cells and migrated cells were detected by the transwell assay. The epithelial-mesenchymal transition (EMT) and the nuclear factor-κB (NF-κB) were performed using Western blot. The tumor growth was measured via xenograft tumor formation assay. Moreover, bioinformatical methods and luciferase reporter assay were carried out to confirm the miR-16 target gene. RESULTS: MiR-16 expression was downregulated in HCC tissues and cells. Furthermore, the increasing miR-16 expression was suppressed, whereas the decreasing miR-16 expression promoted cell proliferation, invasion, and migration in Huh7 cells. Moreover, miR-16 targeted FEAT in regulating HCC progression. FEAT was associated with a poor prognosis of HCC patients. Especially, miR-16 suppressed EMT and NF-κB pathway in HCC and inhibited the tumor growth in vivo. CONCLUSIONS: We stated that miR-16 suppressed HCC cell progression by targeting FEAT and inhibiting EMT and NF-κB pathway. MiR-16 may be clinically utilized as a factor for the clinical diagnosis and prognosis of HCC.

Alteration of plasma cytokines in patients with active epilepsy.

OBJECTIVE: Emerging evidence suggests that inflammatory cytokines are involved in pathophysiology of epilepsy. However, possible interaction between the cytokines and active epilepsy remains unclear. This study aimed to interictal and postictal plasma cytokines in active epilepsy patients. MATERIALS AND METHODS: We enrolled 48 patients with active epilepsy and 30 healthy adults and measured postictal and interictal interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interferon gamma (IFN-γ), interleukin-10 (IL-10), and interleukin-17A (IL-17A) concentrations in peripheral blood by enzyme-linked immunosorbent assay (ELISA). RESULTS: We found postictal and interictal concentrations of IL-6, IL-17A, and IFN-γ were significantly elevated in epilepsy patients compared with healthy controls. There were no significant postictal and interictal alterations of IL-1ß, IL-6, TNF-α, IFN-γ, IL-10, and IL-17A in patients with generalized seizures compared to those with partial seizures, in carbamazepine (CBZ)-treated patients compared to valproic acid (VPA)-treated patients or in temporal lobe epilepsy (TLE) patients compared to extra-temporal lobe epilepsy (eTLE) patients. Furthermore, multivariate linear regression analysis revealed that interictal IL-17A concentration positively correlated with National Hospital Seizure Severity Scale (NHS3) scores (B=0.092, P=.007) and seizure frequency (B=0.045, P=.000). Interictal IFN-γ concentration was also showed positively correlation with seizure frequency (B=0.019, P=.004). CONCLUSIONS: Our data suggest that postictal and interictal various inflammatory cytokines are elevated in plasma of active epilepsy patients. Furthermore, interictal IL-17A and IFN-γ may predict seizure severity.

The protein kinase C (PKC) inhibitors combined with chemotherapy in the treatment of advanced non-small cell lung cancer: meta-analysis of randomized controlled trials.

BACKGROUND: The application of newer signaling pathway-targeted agents has become an important addition to chemotherapy in the treatment of advanced non-small cell lung cancer (NSCLC). In this study, we evaluated the efficacy and toxicities of PKC inhibitors combined with chemotherapy versus chemotherapy alone for patients with advanced NSCLC systematically. PATIENTS AND MATERIALS: Literature retrieval, trials selection and assessment, data collection, and statistic analysis were performed according to the Cochrane Handbook 5.1.0. The outcome measures were tumor response rate, disease control rate, progression-free survival (PFS), overall survival (OS), and adverse effects. RESULTS: Five randomized controlled trials, comprising totally 1,005 patients, were included in this study. Meta-analysis showed significantly decreased response rate (RR 0.79; 95 % CI 0.64-0.99) and disease control rate (RR 0.90; 95 % CI 0.82-0.99) in PKC inhibitors-chemotherapy groups versus chemotherapy groups. There was no significant difference between the two treatment groups regarding progression-free survival (PFS, HR 1.05; 95 % CI 0.91-1.22) and overall survival (OS, HR 1.00; 95 % CI 0.86-1.16). The risk of grade 3/4 neutropenia, leucopenia, and thrombosis/embolism increased significantly in PKC inhibitors combination groups as compared with chemotherapy alone groups. CONCLUSION: The use of PKC inhibitors in addition to chemotherapy was not a valid alternative for patients with advanced NSCLC.

Antineoplastic therapy combined with whole brain radiation compared with whole brain radiation alone for brain metastases: a systematic review and meta-analysis.

BACKGROUND: The standard treatment for brain metastases is whole brain radiation, but the medium survival is about 3-10 months and hadn't be improved for years. AIM: This study was to evaluate the effect of antineoplastic therapy combined with whole brain radiation for brain metastases. MATERIALS AND METHODS: We searched PubMed, EMBASE, Cochrane Library, Chinese Biomedical Literature Database, China Journal Full Text Database and references of the included studies up to May 2011. Randomized controlled trials involving antineoplastic combined with whole brain radiation compare with whole brain radiation alone for brain metastases were analysed. Study selection, data collection and quality assessment of studies were performed by two individual reviewers according to the Cochrane Handbook for systematic reviews of interventions 5.0.2. Statistic analyses were calculated using RevMan5.0.17 software. 9 randomized controlled trails, a total of 1582 patients were included. RESULTS: There were no significant differences in overall survival, six to twenty-four months survival rate and death from central nervous system (CNS) cause, only the objective response rate was statistically higher in the combined group. (RR = 1.47, 95% CI: 1.10, 1.97; p = 0.009) Subgroup analysis of lung cancer got the same result, except that death from central nervous system (CNS) cause was higher in the combined therapy group, it was statistical significant (RR = 0.70, 95% CI: 0.53, 0.93; p = 0.01). CONCLUSIONS: The benefit of antineoplastic combined with whole brain radiation for brain metastases was not concerned, either in the brain metastases from unselected primary tumors or lung cancer.