Impact of non-emergency surgical timing on postoperative recovery quality in mild or asymptomatic SARS-CoV-2 infected patients: a grouped cohort study.

OBJECTIVE: To explore the relationship between the timing of non-emergency surgery in mild or asymptomatic SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infected individuals and the quality of postoperative recovery from the time of confirmed infection to the day of surgery. METHODS: We retrospectively reviewed the medical records of 300 cases of mild or asymptomatic SARS-CoV-2 infected patients undergoing elective general anaesthesia surgery at Yijishan Hospital between January 9, 2023, and February 17, 2023. Based on the time from confirmed SARS-CoV-2 infection to the day of surgery, patients were divided into four groups: ≤2 weeks (Group A), 2-4 weeks (Group B), 4-6 weeks (Group C), and 6-8 weeks (Group D). The primary outcome measures included the Quality of Recovery-15 (QoR-15) scale scores at 3 days, 3 months, and 6 months postoperatively. Secondary outcome measures included postoperative mortality, ICU admission, pulmonary complications, postoperative length of hospital stay, extubation time, and time to leave the PACU. RESULTS: Concerning the primary outcome measures, the QoR-15 scores at 3 days postoperatively in Group A were significantly lower compared to the other three groups (P < 0.05), while there were no statistically significant differences among the other three groups (P > 0.05). The QoR-15 scores at 3 and 6 months postoperatively showed no statistically significant differences among the four groups (P > 0.05). In terms of secondary outcome measures, Group A had a significantly prolonged hospital stay compared to the other three groups (P < 0.05), while other outcome measures showed no statistically significant differences (P > 0.05). CONCLUSION: The timing of surgery in mild or asymptomatic SARS-CoV-2 infected patients does not affect long-term recovery quality but does impact short-term recovery quality, especially for elective general anaesthesia surgeries within 2 weeks of confirmed infection. Therefore, it is recommended to wait for a surgical timing of at least greater than 2 weeks to improve short-term recovery quality and enhance patient prognosis.

Immunogenicity Analysis of the Recombinant Plasmodium falciparum Surface-Related Antigen in Mice.

Plasmodium falciparum, mainly distributed in tropical and subtropical regions of the world, has received widespread attention owing to its severity. As a novel protein, P. falciparum surface-related antigen (PfSRA) has the structural and functional characteristics to be considered as a malaria vaccine candidate; however, limited information is available on its immunogenicity. Here, we expressed three fragments of recombinant PfSRA in an Escherichia coli system and further analyzed its immunogenicity. The results showed that rPfSRA-immunized mice produced specific antibodies with high endpoint titers (1:10,000 to 1:5,120,000) and affinity antibodies (i.e., rPfSRA-F1a (97.70%), rPfSRA-F2a (69.62%), and rPfSRA-F3a (91.87%)). In addition, the sera of immunized mice recognized both the native PfSRA and recombinant PfSRA, the rPfSRA antibodies inhibited the invasion of P. falciparum into the erythrocytes, and they were dose-dependent in vitro. This study confirmed PfSRA could be immunogenic, especially the F1a at the conserved region N-terminal and provided further support for it as a vaccine candidate against P.falciparum.

Thermo-sensitivity of hybrid nanogels for specific endogenous hydrogen sulfide detection and efficient flash chill treatment.

Thermo-responsive nanogels, poly(NIPAM-AAM) were prepared by a facile method of free radical one-pot precipitation based on monomeric N-isopropylacrylamide (NIPAM). At the same time, surface carboxyl group-modified fluorescent conjugated polymer nanoparticles (PNPs-COOH) were immobilized in the nanogel networks by hydrogen bonding to show bright green photoluminescence and outstanding thermo-responsive properties with a typical two-phase Tai Chi structure. Poly(NIPAM-AAm)-PNPs-COOH displays a larger change of hydrodynamic diameter (Dh) and a reversible volume transition from ∼150 nm at 40 °C to ∼1.0 µm at 4 °C. The change will cause apoptosis of cells to finish flash chill treatment. Meanwhile, the fluorescence of poly(NIPAM-AAm)-PNPs-COOH demonstrates reversible quenching and recovery with the expansion and collapse of the nanogel network induced by temperature changes. In addition, when adding Fe3+, the fluorescence of poly(NIPAM-AAm)-PNPs-COOH can be quenched due to the chelation between the PNPs-COOH and Fe3+ and then recovered in the presence of hydrogen sulfide because the chelate is broken; this was attributed to the stronger affinity between Fe3+ and S2-. Therefore, the fluorescence nanoplatform, Fe3+/poly(NIPAM-AAm)-PNPs-COOH, was successfully used to detect endogenous hydrogen sulfide in living A549 cells.

Adaptive immune responses mediated age-related Plasmodium yoelii 17XL and 17XNL infections in 4 and 8-week-old BALB/c mice.

BACKGROUD: It is important to expound the opposite clinical outcomes between children and adulthood for eradicate malaria. There remains unknown about the correlation between adaptive immune response and age-related in malaria. METHODS: 4 and 8-week-old mice were used to mimic children and adulthood, respectively. Parasitemia and the survival rate were monitored. The proportion and function of Th1 and Th2 cells were detected by FACS. The levels of IFN-γ, IL-4, total IgG, IgG1, IgG2a and Plasmodium yoelii MSP-1-specific IgG were measured by ELISA. RESULTS: The adult group showed greater resistance to P. yoelii 17XL infection, with lower parasitemia. Compared with 4-week-old mice, the percentage of CD4+T-bet+IFN-γ+ Th1 cells as well as IFN-γ production were significantly increased on day 5 p.i. in the 8-week-old mice after P. yoelii 17XNL infection. The percentage of CD4+GATA3+IL-4+ Th2 cells and CD4+CXCR5+ Tfh cells, and IL-4 production in the 8-week-old mice significantly increased on day 5 and day 10 after P. yoelii 17XNL infection. Notably, the levels of total IgG, IgG1, IgG2a and P. yoelii MSP-1-specific IgG were also significantly increased in the 8-week-old mice. PD-1, a marker of exhaustion, was up-regulated on CD4+ or activated CD4+ T cells in the 8-week-old mice as compared to the 4-week-old group. CONCLUSIONS: Thus, we consider that enhanced cellular and humoral adaptive immunity might contribute to rapid clearance of malaria among adults, likely in a PD-1-dependent manner due to induction of CD4+ T cells exhaustion in P. yoelii 17XNL infected 8-week-old mice.

The sensitive "Turn-on" fluorescence platform of ascorbic acid based on conjugated polymer nanoparticles.

Ascorbic acid (AA) is very important for maintaining the normal physiological processes of the organism. In order to overcome the shortcomings of existing methods, such as lower sensitivity, complex operations and expensive instruments, it is urgent to develop a simple and rapid method for the determination of AA in the field of food and pharmaceutical preparations. Conjugated polymer nanoparticles (CPNs) have lately aroused wide concerns because of excellent optical properties, biocompatibility and stability. In our work, a CPNsPBOC-COOH fluorescence platform based on Poly [3-{2,5-bis (2-ethyl-hexyloxy)]-phenyl}-vinyl}-9-octyl-carbazole] (PBOC) and Polystyrene-maleic anhydride (PSMA), was prepared for the quantitative detection of AA. Experimental results were showed that this platform was highly selective and sensitive to AA. The concentration of AA detected by the fluorescence platform has a linear relationship in the range of 0.57-17.10 µM. The limit of detection (LOD) is 10 nM, which is lower than other methods reported. More interestingly, the fluorescence of CPNsPBOC-COOH can be controlled by logic gates with Fe3+ and AA. Finally, the designed fluorescence platform has been successfully applied to the analysis of AA in actual samples (vitamin C tablets, mouse serum and plasma), indicating the designed platform with a good feasibility.

Enhanced Two-Photon Fluorescence and Fluorescence Imaging of Novel Probe for Calcium Ion by Self-Assembly with Conjugated Polymer.

The calcium ion (Ca2+) isa highly versatile intracellular signal messenger regulating many different cellular functions. It is important to design probes with good fluorescence and two-photon (TP) active cross-sections (Φδ) to explore the concentration distribution of Ca2+. In this manuscript, a novel TP fluorescence calcium probe (BAPTAVP) with positive charges, based on the classical Ca2+ indicator of BAPTA (1,2-bis(2-aminophenoxy)-ethane-N,N,N',N'-tetra acetic acid), and a conjugated polymer (PCBMB) with negative charges were designed and synthesized. The results from transmission electron microscopy (TEM), atomic force microscopy (AFM), dynamic light scattering (DLS), and the zeta potential (ZP) showed that nanoparticles were obtained by the self-assembly of PCBMB and BAPTAVP. Moreover, the fluorescence properties of BAPTAVP were effectively improved by fluorescence resonance energy transfer (FRET) with PCBMB and attenuating the intramolecular charge transfer (ICT) after the addition of Ca2+. The quantum yield and Φδ of PCBMB-BAPTAVP increased by about four and six times in comparison to those of BAPTAVP, respectively. The TP fluorescence imaging experiments indicated that the PCBMB-BAPTAVP system could effectively detect Ca2+ in living cells with high sensitivity.

Highly Sensitive Detection of Melamine Based on the Fluorescence Resonance Energy Transfer between Conjugated Polymer Nanoparticles and Gold Nanoparticles.

Adding melamine as additives in food products will lead to many diseases and even death. However, the present techniques of melamine detection require time-consuming steps, complicated procedures and expensive analytical apparatus. The fluorescent assay method was facile and highly sensitive. In this work, a fluorescence resonance energy transfer (FRET) system for melamine detection was constructed based on conjugated polymer nanoparticles (CPNs) and gold nanoparticles (AuNPs). The energy transfer efficiency is up to 82.1%, and the system is highly selective and sensitive to melamine detection with a lower detection limit of 1.7 nmol/L. Moreover, the interaction mechanism was explored. The results showed that the fluorescence of CPNs were firstly quenched by AuNPs, and then restored after adding melamine because of reducing FRET between CPNs and AuNPs. Lastly, the proposed method was carried out for melamine detection in powdered infant formula with satisfactory results.

Inhibition of platelet-derived growth factor receptor ß reduces reactive glia and scar formation after traumatic brain injury in mice.

Brain injury leads to complex cellular and molecular interactions within the central nervous system. As the glial scar was a mechanical barrier to regeneration, inhibitory molecules in the forming scar and methods to overcome them have suggested molecular modification strategies to allow neuronal growth and functional regeneration. Here we investigated the roles of PDGFRß signaling in regulating astrocyte reactivity and scar formation in mice following traumatic brain injury (TBI). The expression and distribution of phosphorylated PDGFRß was analyzed, and its cell type-specific expression was verified with double labeling of astrocytes (GFAP), microglia (IBA1), oligodendrocyte precursor cells (OPC) (NG2) and leukocytes (CD45). We found PDGFRß was activated around the injury site after TBI, and primarily expressed in astrocytes, microglia, OPC and leukocytes in the boundary of the lesion site, suggesting PDGFRß was involved in glial scar formation. Then the PDGFR inhibitor (AG1296) was administered following TBI. Reactive astrocytes were significantly inhibited in AG1296-treated mice. Furthermore, AG1296-treatment attenuated reactive leukocytes, OPC and astrocytes and pronouncedly disrupted of glial scar formation after TBI. These findings prove that PDGFRß signaling inhibited reactive glia-mediated scar formation after TBI in mice.

[Construction of recombinant shuttle plasmid pIMP1-eHER2/neu and screening and identification of its stable Clostridium sporogenes transformants].

AIM: To construct recombinant clostridium sporogenes modified with the extracellular domain of human oncogene HER2/neu, to lay a foundation for further study of its antitumor effect. METHODS: The extracellular domain (ECD) of HER2/neu gene was attached to the downstream of promoter and signal sequence of clostridia endo-1, 4-glucanase (eglAp) by SOE-PCR to construct fusion gene eglAp-HER2/neu, which was then inserted into E.coli-clostridia shuttle plasmid pIMP1 to construct recombinant plasmid pIMP1-eHER2/neu. The recombinant plasmid was firstly transformed into E.coli DH5α.Then the correct construct was identified and introduced into C. sporogenes by electroporation. Positive clones were selected by erythromycin resistance, bacteria PCR were used for verification. RESULTS: Restriction map and sequencing result showed that the sequence and ORF of fusion gene eglAp-HER2/neu in recombinant plasmid pIMP1-eHER2/neu was correct. Bacteria PCR results indicated that the recombinant plasmid pIMP1-eHER2/neu was successfully transformed into C.sporogenes. After more than 20 passages under antibiotic pressure, C.sporogenes transformants could stably carry the recombinant plasmid pIMP1-eHER2/neu. CONCLUSION: Stable C.sporogenes transformants with the recombinant plasmid pIMP1-eHER2/neu are successfully acquired, which laid a foundation for further anti-tumor study.

[Knocking down human CD59 gene expression decreased protection to complement-mediated cytolysis].

AIM: To construct recombinant vectors expressing siRNA that target CD59 gene and a stable-inhibit cell line A2780 in order to analyze the role of CD59 in the protection to complement-mediated cytolysis. METHODS: The 60 bp encoded targeting CD59 gene shRNA sequence was cloned into pSUPER vector with DNA recombinant technique. The ovary cancer cell A2780 was transfected with this recombinant plasmid using liposome and the stable strains was selected by using G418-medium, CD59 mRNA and protein level was detected by RT-PCR and Western blot, and its function was analysed by dye release assay. RESULTS: The pSUPER-siRNA expressing vector was successfully constructed. And a stable cell line A2780 was selected and was detected the expression of GFP. The siRNA vector effectively inhibited the CD59 gene expression from mRNA and protein level. Dye release assay suggested that CD59's protection to complement-mediated cytolysis decreased. CONCLUSION: The siRNA vector targeting CD59 gene could consistently inhibit CD59 expression. Furthermore, it decreased CD59's protection against complement. These results may pave the way for studying the role of CD59 in the immune escape of tumors cells as well as in tumor therapy.