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1.
3D Print Addit Manuf ; 11(2): e801-e811, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38689907

RESUMO

Laser powder bed fusion (LPBF) of complex-structure 316L stainless steel (316L ss) parts has a wide application prospects in aerospace, biomedical, and defense industry fields. However, the surface roughness (Ra) of the LPBF sample is unsatisfactory due to the process characteristics of layer-by-layer selective melting and cumulative forming, which limits its applications in the engineering field. Herein, a gradient voltage electrochemical polishing strategy is proposed based on the characteristics of electrochemical polishing technology, which can polish complex structures. The mechanisms of polishing process parameters and polishing strategy on the surface finish of LPBF parts are investigated. The gradient voltage polishing strategy is extended to complex structures, and the Ra of the inner surfaces of square and round tubes are successfully reduced to about 1 µm. The gradient electrochemical polishing process for surface finish post-treatment of LPBF parts can broaden the engineering applications of complex-structure metal parts.

2.
Poult Sci ; 103(7): 103800, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38743966

RESUMO

The combination of inflammatory factors resulting from an influenza A virus infection is one of the main causes of death in host animals. Studies have shown that guinea pig guanosine monophosphate binding protein 1 (guanylate-binding protein 1, gGBP1) can downregulate cytokine production induced by the influenza virus. Therefore, exploring the innate immune defense mechanism of GBP1 in the process of H5N1 influenza virus infection has important implications for understanding the pathogenic mechanism, disease prevention, and the control of influenza A virus infections. We found that, in addition to inhibiting the early replication of influenza virus, gGBP1 also inhibited the production of CCL2 and CXCL10 cytokines induced by the influenza virus as well as the proliferation of mononuclear macrophages induced by these cytokines. These findings further confirmed that gGBP1 inhibited the production of cytokines through its GTPase activity and cell proliferation through its C-terminal α-helix structure. This study revealed the effect of gGBP1 on the production of cellular inflammatory factors during influenza virus infection and determined the key amino acid residues that assist in the inhibitory processes mediated by gGBP1.


Assuntos
Proteínas de Ligação ao GTP , Virus da Influenza A Subtipo H5N1 , Animais , Virus da Influenza A Subtipo H5N1/fisiologia , Virus da Influenza A Subtipo H5N1/imunologia , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/imunologia , Citocinas/metabolismo , Citocinas/genética , Influenza Aviária/virologia , Influenza Aviária/imunologia , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/genética , Imunidade Inata , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/imunologia , Galinhas
3.
Front Pharmacol ; 15: 1348360, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476325

RESUMO

Background: Cardiogenic shock (CS) is the primary cause of death in patients suffering acute myocardial infarction. As an emerging and efficacious therapeutic approach, Chinese herbal injections (CHIs) are gaining significant popularity in China. However, the optimal CHIs for treating CS remain uncertain. Method: We searched eight databases from inception to 30 September 2023. Subsequently, we conducted the Bayesian network meta-analysis (NMA). Interventions were ranked based on the surface under the cumulative ranking curve (SUCRA) probability values. To compare the effects of CHIs on two distinct outcomes, a clustering analysis was performed. Furthermore, the quality of the studies was assessed. Results: For the study, we included 43 RCTs, encompassing 2,707 participants. The study evaluated six herbal injections, namely, Shenfu injection (SF), Shengmai injection (SM), Shenmai injection (Sm), Danshen injection (DS), Huangqi injection (HQ), and Xinmailong injection (XML). The analysis findings suggested that Sm (MD = -1.05, 95% CI: -2.10, -0.09) and SF (MD = -0.81, 95% CI: -1.40, -0.25) showed better efficacy compared to Western medicine (WM) alone in reducing in-hospital mortality. The SUCRA values revealed that Sm + WM ranked first in terms of in-hospital mortality, cardiac index (CI), and hourly urine output but second in improving left ventricular ejection fraction (LVEF) and mean arterial pressure (MAP). SF + WM, however, had the greatest impact on raising the clinical effective rate. In MAP, SM + WM came out on top. Moreover, in terms of safety, only 14 studies (31.8%), including five types of CHIs: SF, Sm, SM, HQ, and XML, observed adverse drug reactions. Conclusion: To summarize, this analysis discovered that, in terms of patients suffering from CS, CHIs + WM yielded significantly greater advantages than WM alone. Based on in-hospital mortality and the remaining outcomes, Sm performed excellently among all the involved CHIs. Systematic Review Registration: https:// www.Crd.york.ac.uk/prospero/, identifier: CRD42022347053.

5.
Sci Total Environ ; 924: 171606, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38492600

RESUMO

Aluminum-containing deposits are pervasive in drinking water distribution systems (DWDSs). However, the mechanisms driving dissolved Al transformation to pipe deposits remain elusive. This study investigated dissolved Al accumulation in DWDSs by batch experiments and long-term pipe experiments using actual finished water. PVC pipe experiments showed that dissolved Al hardly deposited on clean PVC pipe walls at alkaline pH. However, it could be substantially anchored by the pipe surface covered with Mn and Fe deposits formed from Mn(II) oxidation and Fe(III) precipitation. Batch experiments verified that the synthesized Mn and Fe oxides exhibited a strong capacity for dissolved Al uptake at pH 7.7 and 9.0 (dissolved Al was the dominant form). Biofilms on pipe walls also enhanced dissolved Al accumulation. Iron pipe experiments showed that corroded iron pipes with abundant iron corrosion products readily accumulated Al. Compared to chlorination and chloramination, non-disinfected conditions were more favorable for particulate Al deposition on iron pipe surface, probably due to Al immobilization by biofilms. In addition, continuous Al accumulation in iron pipes enhanced Fe release to pipe water. This study highlighted the important role of metal oxides in dissolved Al accumulation in DWDSs with abundant Mn and Fe solids, which provided new insights into deposit formation and control strategies.

6.
Sci Total Environ ; 920: 171001, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38365033

RESUMO

Manganese(II) (Mn(II)) and bromide (Br-) are common in natural waters. This study investigated the effect of in-situ Mn(II) oxidation and preformed MnOx on the brominated trihalomethane (Br-THM) formation during chlorination of bromide-containing waters. The results showed Br-THM formation could be substantially inhibited by in-situ Mn(II) oxidation, but the addition of preformed MnOx had limited influence on Br-THM formation during chlorination of bromide-containing waters. Analysis of bromine species showed that about 30 % bromine species were incorporated into the MnOx particles and formed MnOx-Br during the in-situ Mn(II) oxidation process. Consequently, the availability of reactive bromine species for the reaction with dissolved organic matter (DOM) reduced, leading to less Br-THM formation. X-ray diffraction (XRD) analysis of in-situ Mn(II) oxidation product indicated the presence of Br- decreased the crystallinity of Mn oxides, verifying the bromine species entered MnOx crystal. However, the adsorptive uptake of bromine species by preformed MnOx was negligible and had no impact on Br-THM formation. Inhibition rate of Mn(II) oxidation on THM formation decreased with increasing specific ultraviolet absorbance (SUVA254) value of filtered water, showing SUVA254 could be a good indicator of DOM competition ability for oxidant with Mn(II). In addition, Excitation/Emission Matrix indicated that Mn(II) could form complexes with humic substances, which might also retard the reaction between humic substances and oxidant to form Br-THMs. This study highlighted the inhibiting effect of in-situ Mn(II) oxidation on Br-THM formation during chlorination of bromide-containing waters.

7.
Water Res ; 251: 121142, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38246084

RESUMO

MnOx deposits in distribution pipes can cause severe discoloration problems in drinking water. However, the impact of pipe materials on Mn(II) oxidation and MnOx accumulation remains unclear. This study investigated microbial-mediated Mn(II) oxidation and deposit formation through 300-day pipe loop experiments with corroded galvanized steel pipes (DN100) and new polyvinyl chloride (PVC) pipes (DN100). The results showed that influent Mn(II) was entirely oxidized within 48 h in the PVC pipes with biofilms in the absence of chlorine, while most influent Mn(II) remained unoxidized in the iron pipes. Dissolved oxygen (DO) monitoring showed that the DO in the PVC pipes was consistently higher than 8.0 mg/L, but that in the iron pipes dropped to 6.5 mg/L. Microbial analysis revealed that the abundance of potential Mn(II)-oxidizing bacteria in the low-DO iron pipes was less than that in the PVC pipes. Analysis of the Mn(II) concentration dynamics in different pipes revealed that the early Mn(II) disappearance in the iron pipes was contributed mainly to Mn(II) adsorption by iron corrosion products rather than microbial Mn(II) oxidation. When aeration was performed to increase the DO concentration to 8.0 mg/L in the iron pipes, complete Mn(II) oxidation occurred. This study provides insights into Mn(II) transformation in different pipes and highlights the critical role of DO in microbial Mn(II) oxidation in drinking water pipes.


Assuntos
Água Potável , Ferro , Abastecimento de Água/métodos , Oxirredução , Corrosão
8.
Int J Biol Macromol ; 253(Pt 1): 126294, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37633565

RESUMO

Clinically, modified autologous rib cartilage grafts and commercial implants are commonly used for intraoperative repair of auricular cartilage defects caused by injuries. However, scaffold implantation is often accompanied by various complications including absorption and collapse, resulting in undesirable clinical outcomes. Three-dimensional printed auricular cartilage scaffolds have the advantage of individual design and biofunctionality, which attracted tremendous attention in this field. In this study, to better simulate the mechanical properties of auricular cartilage, we tested PU treated by ultrasonication and high temperature for 30 min (PU-30) or 60 min (PU-60). The results indicated that the compression modulus of PU-30 was 2.21-2.48 MPa, which similar to that of natural auricular cartilage (2.22-7.23 MPa) and was chosen for subsequent experiments. And the pores of treated PU were filled with a gelatin/sodium alginate hydrogel loaded with chondrocytes. In vivo analysis using a rabbit model confirmed that implanted PU-30 scaffold filled with chondrocytes contained hydrogel successfully integrated with normal auricular cartilage, and that new cartilage was generated at the scaffold-tissue interface by histological examination. These findings illustrate that this engineered scaffold represents a potential strategy for repair of ear cartilage damage in clinical.


Assuntos
Condrócitos , Cartilagem da Orelha , Animais , Coelhos , Condrócitos/transplante , Alicerces Teciduais , Engenharia Tecidual/métodos , Hidrogéis/farmacologia , Gelatina/farmacologia , Alginatos , Impressão Tridimensional
9.
J Hazard Mater ; 458: 131877, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37344241

RESUMO

Sufficient and sustainable manganese(II) removal is a challenging task to prevent Mn-related drinking water discoloration problems. This study investigated Mn(II) removal by granular activated carbon (GAC) filtration under various conditions. The results showed that biological GAC filter columns could reduce Mn(II) from 400 µg/L to 10 µg/L after a short ripening period, while sand filter columns did not show evident Mn(II) removal function. Water quality changes, pretreatment with NaClO and chemogenic MnOx coating on GAC media surface did not influence the Mn(II) removal capacity of GAC filter columns. 16S rRNA gene sequencing showed that the abundance of potential Mn(II)-oxidizing bacteria in the GAC media was similar to that in the sand media. However, qPCR results indicated that GAC media colonized dramatically more biomass than sand media, resulting in highly effective Mn(II) removal by GAC filter columns. Under chlorinated conditions, GAC filtration underperformed sand filtration in Mn(II) removal, although activated carbon has been reported to be capable of catalyzing Mn(II) oxidation by chlorine. Fast chlorine decay in GAC filter columns made it hard to sustain chemical Mn(II) oxidation and thus led to less Mn(II) removal. This study highlighted the advantage of biological GAC filtration over sand filtration in Mn(II) removal.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Carvão Vegetal , RNA Ribossômico 16S , Cloro/análise , Filtração/métodos , Oxirredução , Purificação da Água/métodos , Poluentes Químicos da Água/análise
10.
J Hazard Mater ; 445: 130637, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-37056009

RESUMO

Extending the lifetime of granular activated carbon (GAC) filters with no significant loss in their effectiveness is a considerable challenge for drinking water supply utilities. However, the effects of residual Al from coagulants on GAC performance are rarely considered. Herein, in-service GAC samples obtained from full-scale water treatment plants were investigated to evaluate the amount of accumulated Al. Although the Al concentration in water was two to three times lower than the Ca concentration, Al exhibited considerable accumulation (second to Ca accumulation) in in-service GAC samples (0.68-8.63 mg g-1). Surface characterization results indicated that Al accumulation could have been caused by the co-precipitation of Al with Ca and Si to form Ca4Al2Si3O10·H2O and Ca4Al6O12SO4, self-precipitation or complexion with -OH/-COOH on the GAC or biofilm surfaces. Correlation analysis of the accumulated Al and GAC properties implied that Al accumulation considerably reduced the surface area of GAC by ∼30%. Lab simulation experiments indicated that the removal of dissolved organic matter was reduced by 6-10% when additional Al was loaded. In addition, results showed that the residual Al (up to 200 µg L-1) considerably affected the extracellular polymeric substance component and microorganism community structure. In summary, strict control of residual Al is beneficial for maintaining the efficacies of GAC and biologically activated carbon.

11.
Adv Sci (Weinh) ; 10(12): e2206486, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36683254

RESUMO

4D printing of metallic shape-morphing systems can be applied in many fields, including aerospace, smart manufacturing, naval equipment, and biomedical engineering. The existing forming materials for metallic 4D printing are still very limited except shape memory alloys. Herein, a 4D printing method to endow non-shape-memory metallic materials with active properties is presented, which could overcome the shape-forming limitation of traditional material processing technologies. The thermal stress spatial control of 316L stainless steel forming parts is achieved by programming the processing parameters during a laser powder bed fusion (LPBF) process. The printed parts can realize the shape changing of selected areas during or after forming process owing to stress release generated. It is demonstrated that complex metallic shape-morphing structures can be manufactured by this method. The principles of printing parameters programmed and thermal stress pre-set are also applicable to other thermoforming materials and additive manufacturing processes, which can expand not only the materials used for 4D printing but also the applications of 4D printing technologies.

12.
Environ Sci Technol ; 56(17): 12278-12287, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35976066

RESUMO

The oxidation of residual Mn(II) in finished water can lead to MnOx deposit formation in drinking water pipes. Previous work has illustrated that microbes readily cause Mn deposit build-up in nondisinfected pipes. Here, we investigated how disinfectant type and dose affected Mn(II) oxidation and MnOx accumulation through long-term pipe experiments using water produced by a full-scale water treatment plant. The results showed that Mn(II) oxidation initiated quickly in the new pipes chlorinated with 1.0 mg/L free chlorine. After 130 days of MnOx accumulation, 100 µg/L Mn(II) in water could drop to 1.0 µg/L within 1.5 h, resulting from autocatalytic Mn(II) oxidation and Mn(II) adsorption by MnOx deposits accumulated on pipe walls. In contrast to chlorination, chloramination (1.0 mg/L Cl2) caused almost no MnOx accumulation during the entire study period. The underlying mechanism was probably that monochloramine inhibited microbial Mn(II) oxidation without causing significant abiotic Mn(II) oxidation like free chlorine. A low free chlorine dose (0.3 mg/L) also reduced Mn deposit formation by mass but to a lesser extent than chloramination. After disinfection (chlorination or chloramination) was discontinued for days, biotic Mn(II) oxidation occurred, and this process was inhibited again once disinfection was resumed. In addition, Fe(III) of 200 µg/L enhanced the stability of MnOx accumulated on pipe surfaces, while humic acid induced MnOx deposit resuspension. Overall, this study highlighted the regulating role of disinfectants in MnOx formation and provided insights into developing appropriate disinfection strategies for Mn deposit control.


Assuntos
Desinfetantes , Água Potável , Purificação da Água , Cloraminas , Cloro , Desinfecção/métodos , Compostos Férricos , Manganês , Purificação da Água/métodos
13.
Sci Total Environ ; 848: 157723, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-35914596

RESUMO

Granular activated carbon (GAC) adsorption is one of the best available technologies for removing perfluoroalkyl substances (PFASs) from drinking water. However, GAC processes in full-scale drinking water treatment plants frequently encounter unstable, even negative removal efficiency on PFASs due to the lack of understanding between the GAC characteristics and the PFASs polluted water quality conditions. In this study, the scenarios of raw water pre-chlorination and emergency contamination by multiple PFASs were simulated to evaluate the PFASs control performance by in-service GAC with different properties and ages. The results showed that the adsorption of a relatively longer-chain PFAS by the in-service GAC can be achieved by replacing the pre-adsorbed natural organic matter (NOM). The increased lower molecular weight NOM after pre-chlorination could compete with PFASs for adsorption sites and exacerbate the pore blockage, thus significantly weakening the PFASs removal ability of in-service GAC. When multiple PFASs entered the water by emergency contamination, the PFASs with stronger hydrophobicity could replace the PFASs with less hydrophobicity that had previously been adsorbed on GAC. GAC with a higher proportion of micropores had a lower risk of PFASs leakage facing the water quality changes.


Assuntos
Água Potável , Fluorocarbonos , Poluentes Químicos da Água , Purificação da Água , Adsorção , Carvão Vegetal , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Qualidade da Água
14.
Environ Sci Technol ; 56(15): 10775-10784, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35876009

RESUMO

Mn(II) oxidation by free chlorine can be applied to remove Mn(II) at water treatment plants. This reaction also results in particulate MnOx formation and accumulation in drinking water distribution systems. This study investigated the effect of Fe(III) and Al(III) hydrolysis products (mainly precipitates) on Mn(II) oxidation by free chlorine under drinking water conditions. The results showed that Fe3+ added as FeCl3 and Al(III) added as polyaluminum chloride (PACl) at tens to hundreds of micrograms per liter dramatically catalyzed Mn(II) oxidation by free chlorine. Through hydrolytic precipitation at circumneutral pH, Fe3+ and Al13 (the dominant preformed Al species in PACl) generated Fe(OH)3-like particles and Al13 aggregates, respectively, which initiated heterogeneous Mn(II) oxidation. Kinetic modeling indicated that, once some MnOx was formed, MnOx and Fe(OH)3 catalyzed the subsequent Mn(II) oxidation to an equal extent. The particles (aggregates) formed from Al13 species exhibited a weaker catalytic capacity in comparison to MnOx and Fe(OH)3 at equivalent molar concentrations. Interestingly, unlike Al13 species in PACl, Al(III) added as AlCl3 had a negligible influence on Mn(II) oxidation, even when Al(OH)3(am) precipitates were formed. The catalytic effects of Fe3+ and Al13 hydrolysis products were confirmed by experiments with natural water and finished water, and the lower Mn(II) oxidation rate was mainly attributed to organic matter.


Assuntos
Cloro , Água Potável , Alumínio , Catálise , Cloretos , Compostos Férricos , Hidrólise , Oxirredução
15.
Polymers (Basel) ; 14(12)2022 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-35745961

RESUMO

Fused filament fabrication (FFF) additive manufacturing technology has the advantages of being low cost, having a simple operation, using wide types of molding materials, and producing less pollution during the printing process. However, the mechanical properties of the molded sample are unsatisfactory due to the limited bonding force between the filaments during the forming process, which limits its further development and application in the engineering field. Herein, the hybrid additive manufacturing technology for heterogeneous materials based on the ultrasonic-assisted enhanced fused filament fabrication technology was proposed. The mechanism of ultrasonic vibration on the strengthening of FFF samples was explored. The influence mechanisms of bonding time and ultrasonic strengthening times, ultrasonic strengthening and static load compression on the strengthening of mechanical properties of the sample were investigated. The effects of the thickness and printing angle of the FFF samples on the ultrasonic-enhanced mechanical properties were explored. The tensile strength of the one-time ultrasonic-strengthened sample is up to 43.43 MPa, which is 16.12% higher than that of the original. The maximum bending strength of the four-time ultrasonic-strengthened sample is 73.38 MPa, which is 78.98% higher than that of the original. Ultrasonic strengthening not only re-fused the pores inside the sample, but also improved the bond strength between the rasters. With the increase in the thickness of the sample, the increase rate of ultrasonic to the strength of the sample decreased significantly. The effects of ultrasound on the interlayer adhesion of samples with various printing angles were different. Based on the systematic research on the influence mechanism of ultrasonic process parameters and molding process parameters on the strengthening of FFF, a molding method for additively manufacturing heterogeneous material parts while strengthening the mechanical properties of FFF samples was proposed, and the influence mechanisms of the molding process on the mechanical properties and shape memory properties of the sample were explored, which can broaden the application of FFF technology in the engineering field.

16.
Front Immunol ; 13: 849409, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711427

RESUMO

We developed Lactobacillus casei bacterial ghosts (BGs) as vehicles for delivering DNA vaccines and analyzed their effects on immune responses. Uptake of the plasmids encoding the enhanced green fluorescent protein (pCI-EGFP) and BGs loaded with pCI-EGFP by macrophages was investigated using fluorescence microscopy and flow cytometry. The results showed that pCI-EGFP-loaded L. casei BGs were efficiently taken up by macrophages. Lactobacillus casei BGs loaded with plasmids encoding VP6 protein of PoRV (pCI-PoRV-VP6) significantly upregulated the mRNA expression of interleukin (IL)-1ß, IL-10, tumor necrosis factor (TNF)-α, inducible nitric oxide synthase (iNOS), arginase-1 (Arg-1), Mannose receptor (CD206) toll-like receptor (TLR)-2, TLR4, and TLR9 in macrophages. The levels of markers of M1 polarization (IL-10 and TNF-α) and M2 polarization (Arg-1 and CD206) were increased in macrophages incubated with pCI-PoRV-VP6-loaded BGs compared with the control group. The results of the enzyme-linked immunosorbent assay showed that the secretion of IL-1ß, IL-10, and TNF-α in macrophages was significantly upregulated compared with the control group. Flow cytometry demonstrated that L. casei BGs loaded with pCI-PoRV-VP6 promoted the maturation of dendritic cells (DCs). Following incubation with pCI-PoRV-VP6-loaded BGs, the mRNA expression levels of IL-1ß, IL-6 and interferon (IFN)-γ in DCs were significantly increased. ELISA assay showed the secretion of the IL-1ß, IL-6, IFN-γ IL-10 and TNF-α in DCs were upregulated significantly. Thus, L. casei BGs promoted the maturation and activation of DCs. We analyzed the stimulatory capacity of DCs in a mixed lymphocyte reaction with allogeneic T cells. T cell proliferation increased upon incubation with DCs stimulated by BGs. After immunizing mice with BGs loaded with pCI-PoRV-VP6, the specific IgG levels in the serum were higher than those elicited by BGs loaded with pCI-PoRV-VP6. BGs loaded with pCI-PoRV-VP6 on Th1 and Th2 cytokines polarized T cells into the Th1 type and increased the proportion of CD4+/CD8+ T cells. These results indicate L. casei BGs effectively mediate immune responses and can be used as delivery system for DNA vaccination.


Assuntos
Lacticaseibacillus casei , Vacinas de DNA , Animais , Linfócitos T CD8-Positivos/metabolismo , Imunidade , Interleucina-10/metabolismo , Interleucina-6 , Camundongos , RNA Mensageiro , Fator de Necrose Tumoral alfa/metabolismo
17.
Polymers (Basel) ; 14(10)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35631954

RESUMO

Spider silks exhibit excellent mechanical properties and have promising application prospects in engineering fields. Because natural spider silk fibers cannot be manufactured on a large scale, researchers have attempted to fabricate bio-inspired spider silks. However, the fabrication of bio-inspired spider silks with dynamically tunable mechanical properties and stimulation-response characteristics remains a challenge. Herein, the 4D printing of shape memory polyurethane is employed to produce dynamic bio-inspired spider silks. The bio-inspired spider silks have two types of energy-absorbing units that can be adjusted, one by means of 4D printing with predefined nodes, and the other through different stimulation methods to make the bio-inspired spider silks contract and undergo spiral deformation. The shape morphing behaviors of bio-inspired spider silks are programmed via pre-stress assemblies enabled by 4D printing. The energy-absorbing units of bio-inspired spider silks can be dynamically adjusted owing to stress release generated with the stimuli of temperature or humidity. Therefore, the mechanical properties of bio-inspired spider silks can be controlled to change dynamically. This can further help in developing applications of bio-inspired spider silks in engineering fields with dynamic changes of environment.

18.
Front Pharmacol ; 13: 830030, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35370733

RESUMO

Background: Sepsis has high mortality and is responsible for significant healthcare costs. Chinese herbal injections (CHIs) have been widely used in China as a novel and promising treatment option for sepsis. Therefore, this study assessed and ranked the effectiveness of CHIs to provide more sights for the selection of sepsis treatment. Method: Eight databases were searched from their inception up to September 1, 2021. The methodological quality of included study was evaluated by the Revised Cochrane risk-of-bias tool for randomized trials. Then Bayesian network meta-analysis was performed by OpenBUGS 3.2.3 and STATA 14.0 software. The surface under the cumulative ranking curve (SUCRA) probability values were applied to rank the examined treatments. Publication bias was reflected by a funnel plot. Results: A total of 50 eligible randomized controlled trials involving 3,394 participants were identified for this analysis. Five CHIs including Shenfu injection, Shenmai injection, Shengmai injection, Shenqifuzheng injection, and Huangqi injection were included. The results of the NMA and sensitivity analysis showed that Shenqifuzheng (MD = -4.48, 95% CI = -5.59 to -3.24), Shenmai (MD = -3.38, 95% CI = -4.38 to -2.39), Shenfu (MD = -2.38, 95% CI = -3.03 to -1.70) and Shengmai (MD = -1.90, 95% CI = -3.47 to -0.31) combined with Western medicine (WM) had a superior effect in improving the APACHE II score. Based on SUCRA values, Shenqifuzheng injection (95.65%) ranked highest in the APACHE II score, followed by Shenmai (74%), Shenfu (47.1%), Shengmai (35.3%) and Huangqi injection (33.2%). Among the secondary outcomes, Shenmai injection was the most favorable intervention in reducing PCT and CRP levels, and Shenqifuzheng injection was the second favorable intervention in reducing CRP level. Shenfu injection combined with WM was more effective than the other treatments in decreasing the serum IL-6 and TNF-α levels and lowering the 28-days mortality. Regarding the improvement of immune function, Shenqifuzheng injections had obvious advantages. Conclusion: In conclusion, Shenqifuzheng injection was the optimum treatment regimen to improve APACHE II score, reduce CRP level, and regulate immune function. Shenfu injection was superior in reducing the expression of inflammatory factors and decreasing 28-days mortality. Nevertheless, more multicenter, diverse, and direct comparisons randomized controlled trials are needed to further confirm the results. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=254531, identifier CRD42021254531.

19.
Environ Sci Technol ; 56(9): 5497-5507, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35420026

RESUMO

Microbial Mn(II) oxidation occurs in areas with insufficient disinfectants in drinking water distribution systems. However, the overall processes of microbial-mediated Mn deposit formation are unclear. This research investigated the initial Mn(II) oxidation, deposit accumulation, and biofilm development in pipe loops fed with nondisinfected finished water for 300 days. The results show that it took 20 days for microbial Mn(II) oxidation and deposition to be initiated visibly in new pipes continuously receiving 100 µg/L Mn(II). Once started, the deposit accumulation accelerated. A pseudo-first-order kinetic model could simulate the disappearance of Mn(II) in well-mixed pipe loop water. The observed rate constant reached 2.81 h-1 [corresponding to a Mn(II) half-life of 0.25 h] after 136 days of operation. Without oxygen, Mn(II) in the water also decreased rapidly to 1.0 µg/L through adsorption to deposits, indicating that after the initial microbial formation of MnOx, subsequent MnOx accumulation was attributable to a combination of microbial and physicochemical processes. Compared to the no-Mn condition, Mn(II) input resulted in 1 order of magnitude increase in biofilm formation. This study sheds light on the increasingly rapid processes of Mn accumulation on the inner surfaces of water pipes resulting from the biological activity of Mn(II)-oxidizing biofilms and the build-up of MnOx with strong adsorption capacity.


Assuntos
Desinfetantes , Água Potável , Biofilmes , Manganês , Oxirredução
20.
Viruses ; 14(3)2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35337027

RESUMO

The primary aim of this study was to evaluate the efficacy of phage against mastitis induced by drug-resistant S. aureus in a mouse model. In this study, five S. aureus phages-4086-1, 4086-2, 4086-3, 4086-4, and 4086-6-were isolated from milk samples secreted by mastitis cows. Transmission electron microscopy showed that all the five phages had icosahedral heads and short non-contractile tails, which are typical characteristics of the family Podoviridae. All these phages were species-specific against S. aureus. The one-step growth curve showed a short latency period (10-20 min) and high burst size (up to 400 PFU/infected cell). To evaluate the effectiveness of the phage 4086-1 in the treatment against mastitis, a mouse model of mastitis was challenged with drug-resistant S. aureus. The results showed the proliferation of S. aureus in the mammary glands was significantly inhibited after treating by phage 4086-1. The concentrations of TNF-α and IL-6 decreased significantly, which demonstrated the phages could effectively alleviate the inflammatory responses. Furthermore, the histopathological analysis showed that inflammatory infiltration in the mammary glands was significantly reduced. These results demonstrate that phage may be a promising alternative therapy against mastitis caused by drug-resistant S. aureus.


Assuntos
Bacteriófagos , Mastite Bovina , Staphylococcus aureus Resistente à Meticilina , Terapia por Fagos , Infecções Estafilocócicas , Animais , Bovinos , Feminino , Humanos , Mastite Bovina/terapia , Camundongos , Myoviridae , Terapia por Fagos/métodos , Infecções Estafilocócicas/terapia , Staphylococcus aureus
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