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1.
Int J Mol Sci ; 23(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35887393

RESUMO

The spread of multidrug-resistant Klebsiella pneumoniae (MDR-KP) has become an emerging threat as a result of the overuse of antibiotics. Bacteriophage (phage) therapy is considered to be a promising alternative treatment for MDR-KP infection compared with antibiotic therapy. In this research, a lytic phage BUCT610 was isolated from hospital sewage. The assembled genome of BUCT610 was 46,774 bp in length, with a GC content of 48%. A total of 83 open reading frames (ORFs) and no virulence or antimicrobial resistance genes were annotated in the BUCT610 genome. Comparative genomics and phylogenetic analyses showed that BUCT610 was most closely linked with the Vibrio phage pYD38-A and shared 69% homology. In addition, bacteriophage BUCT610 exhibited excellent thermal stability (4-75 °C) and broad pH tolerance (pH 3-12) in the stability test. In vivo investigation results showed that BUCT610 significantly increased the survival rate of Klebsiella pneumonia-infected Galleria mellonella larvae from 13.33% to 83.33% within 72 h. In conclusion, these findings indicate that phage BUCT610 holds great promise as an alternative agent with excellent stability for the treatment of MDR-KP infection.


Assuntos
Bacteriófagos , Mariposas , Animais , Antibacterianos/farmacologia , Genômica , Klebsiella pneumoniae/genética , Larva/genética , Mariposas/genética , Filogenia
2.
Small ; 16(40): e2004072, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32893499

RESUMO

Tin disulfide (SnS2 ) shows promising properties toward sodium ion storage with high capacity, but its cycle life and high rate capability are still undermined as a result of poor reaction kinetics and unstable structure. In this work, phosphate ion (PO4 3- )-doped SnS2 (P-SnS2 ) nanoflake arrays on conductive TiC/C backbone are reported to form high-quality P-SnS2 @TiC/C arrays via a hydrothermal-chemical vapor deposition method. By virtue of the synergistic effect between PO4 3- doping and conductive network of TiC/C arrays, enhanced electronic conductivity and enlarged interlayer spacing are realized in the designed P-SnS2 @TiC/C arrays. Moreover, the introduced PO4 3- can result in favorable intercalation/deintercalation of Na+ and accelerate electrochemical reaction kinetics. Notably, lower bandgap and enhanced electronic conductivity owing to the introduction of PO4 3- are demonstrated by density function theory calculations and UV-visible absorption spectra. In view of these positive factors above, the P-SnS2 @TiC/C electrode delivers a high capacity of 1293.5 mAh g-1 at 0.1 A g-1 and exhibits good rate capability (476.7 mAh g-1 at 5 A g-1 ), much better than the SnS2 @TiC/C counterpart. This work may trigger new enthusiasm on construction of advanced metal sulfide electrodes for application in rechargeable alkali ion batteries.

3.
BMC Gastroenterol ; 20(1): 7, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931737

RESUMO

BACKGROUND: The anti-immunological rejection therapy for small-for-size syndrome (SFSS) after live donor liver transplantation (LDLT) play a central role in keeping graft survival. The hepatocyte number and grafts function has undergone real-time changes with the proliferation and apoptosis of the grafts after reperfusion. Lacking an accurate and effective treatment regiments or indicators to guide the use of immunosuppressive drugs in SFS liver transplantation has made immunotherapy after SFS liver transplantation an urgent problem to be solved. Herein, we established small-for-size (SFS) and normal size liver transplantation model in rats to explore the effective indicators in guiding immunotherapy, to find an effective way for overcoming SFSS. METHODS: Lewis rats (donors) and BN rats (recipients) were used to mimic allograft liver transplantation and treated with tacrolimus. Local graft immune response was analyzed through haematoxylin and eosin and immunohistochemistry. Flow cytometry was used to assess the overall immune status of recipient. The pharmacokinetics mechanism of immunosuppressive drugs was explored through detecting CYP3A2 expression at mRNA level and protein levels. RESULTS: The results showed the local immune reaction of SFS grafts and systemic immune responses of recipient were significantly increased compared with those in normal size grafts and their recipient at four days after liver transplantation. Regression equation was used to regulate the tacrolimus dose which not only controlled tacrolimus serum concentration effectively but alleviated liver damage and improved survival rate. CONCLUSIONS: This study showed that AST level and tacrolimus serum concentrations are effective indicators in guiding immunotherapy. Regression equation (TD = - 0.494TC-0.0035AST + 260.487) based on AST and tacrolimus serum concentration can be used as a reference for adjustment of immunotherapy after SFS liver transplantation, which is applicable in clinical practice.


Assuntos
Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/imunologia , Imunossupressores/uso terapêutico , Transplante de Fígado/efeitos adversos , Tacrolimo/uso terapêutico , Animais , Aspartato Aminotransferases/sangue , Imunossupressores/sangue , Fígado/imunologia , Transplante de Fígado/métodos , Doadores Vivos , Tamanho do Órgão/imunologia , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Tacrolimo/sangue , Transplantes/imunologia , Resultado do Tratamento
4.
Small ; 15(30): e1901796, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31172634

RESUMO

Performance breakthrough of MoSe2 -based hydrogen evolution reaction (HER) electrocatalysts largely relies on sophisticated phase modulation and judicious innovation on conductive matrix/support. In this work the controllable synthesis of phosphate ion (PO43- ) intercalation induced-MoSe2 (P-MoSe2 ) nanosheets on N-doped mold spore carbon (N-MSC) forming P-MoSe2 /N-MSC composite electrocatalysts is realized. Impressively, a novel conductive N-MSC matrix is constructed by a facile mold fermentation method. Furthermore, the phase of MoSe2 can be modulated by a simple phosphorization strategy to realize the conversion from 2H-MoSe2 to 1T-MoSe2 to produce biphase-coexisted (1T-2H)-MoSe2 by PO43- intercalation (namely, P-MoSe2 ), confirmed by synchrotron radiation technology and spherical aberration-corrected TEM (SACTEM). Notably, higher conductivity, lower bandgap and adsorption energy of H+ are verified for the P-MoSe2 /N-MSC with the help of density functional theory (DFT) calculation. Benefiting from these unique advantages, the P-MoSe2 /N-MSC composites show superior HER performance with a low Tafel slope (≈51 mV dec-1 ) and overpotential (≈126 mV at 10 mA cm-1 ) and excellent electrochemical stability, better than 2H-MoSe2 /N-MSC and MoSe2 /carbon nanosphere (MoSe2 /CNS) counterparts. This work demonstrates a new kind of carbon material via biological cultivation, and simultaneously unravels the phase transformation mechanism of MoSe2 by PO43- intercalation.

5.
Nanotechnology ; 30(48): 484001, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31430739

RESUMO

The tailored construction of non-noble metal bifunctional electrocatalysts for high-efficiency oxygen/hydrogen evolution reactions (OER/HER) is vital for the development of electrochemical energy conversion. Herein, we report a powerful combined wet chemical method to fabricate a novel binder-free NiFe layered double hydroxide@Ni3S2 (NiFe LDH@Ni3S2) heterostructure as an efficient bifunctional electrocatalyst for overall water splitting. The hydrothermal-synthesized NiFe LDH nanosheets are uniformly coated on the Ni3S2 nanosheet skeleton forming 3D porous heterostructure arrays. By virtue of its synergistic advantages, including its binder-free characteristics, increased catalysis sites and structural stability, the as-obtained NiFe LDH@Ni3S2/NF electrode exhibits low overpotentials of 184 and 271 mV at 20 mA cm-2 for HER and OER in 1 M KOH, respectively. Notably, a low operation potential of 1.74 V at a current density of 20 mA cm-2 is achieved for overall water splitting with a stable cycling life. In addition, the intimate composite structure and sensitive interface of NiFe LDH@Ni3S2 are responsible for the good electrocatalytic activity with a low Tafel slope, fast reaction kinetics and high stability. The versatile fabrication protocol and heterostructure interface engineering provide a new way to construct other bifunctional and cost-effective electrocatalysts for electrocatalysis.

7.
Front Plant Sci ; 15: 1407984, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38882568

RESUMO

Introduction: Improvement of root architecture is crucial to increasing nutrient acquisition. Methods: Two pot experiments were conducted to investigate the effects of different concentrations of urea ammonium nitrate solution (UAN) and ammonium polyphosphate (APP) on lettuce root architecture and the relationship between roots and nitrogen (N) and phosphorus (P) absorption. Results: The results showed that lettuce yield, quality, and root architecture were superior in the APP4 treatment compared to other P fertilizer treatments. The N480 treatment (480 mg N kg-1 UAN) significantly outperformed other N treatments in terms of root length, root surface area, and root volume. There were significant quantitative relationships between root architecture indices and crop uptake of N and P. The relationships between P uptake and root length and root surface area followed power functions. Crop N uptake was significantly linearly related to the length of fine roots with a diameter of <0.5 mm. Conclusion and discussion: The length of fine roots played a more prominent role in promoting N absorption, while overall root size was more important for P absorption. APP has a threshold of 9.3 mg P kg-1 for stimulating the root system. Above this threshold, a rapid increase in root absorption of P. UAN can promote extensive growth of fine roots with a diameter less than 0.5 mm. Applying appropriate rates of APP and limiting UAN application to less than 400 mg N kg-1 can improve root architecture to enhance N and P absorption by lettuce. These results highlight a new possibility to improve nutrients use efficiency while maintaining high yields.

8.
RSC Adv ; 14(16): 11089-11097, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38586441

RESUMO

Because traditional lithium-ion batteries have been unable to meet the energy density requirements of various emerging fields, lithium-metal batteries (LMBs), known for their high energy density, are considered promising next-generation energy storage batteries. However, a series of problems, including low coulombic efficiency and low safety caused by dendrites, limit the application of lithium metal batteries. Herein, fluoro-oxygen codoped graphene (FGO) was used to modify the copper current collector (FGO@Cu). FGO-coated current collector provides more even nucleation sites to reduce the local effective current density. FGO is partly reduced during cycling and helps form stable LiF-rich SEI. Moreover, graphene's oxygen and fluorine functional groups reconstruct the current density distribution, promoting uniform lithium plating. The FGO@Cu current collector demonstrates superior properties than commercial Cu foil. The FGO@Cu delivers a 97% high CE for over 250 cycles at 1 mA cm-2. The FGO@Cu symmetrical battery cycled at 1 mA cm-2 for over 650 h. LiFePO4 fuel cell with a lithium-plated FGO@Cu collector as an anode exhibits superior cycling stability.

9.
ACS Appl Mater Interfaces ; 16(15): 18949-18958, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38569078

RESUMO

The nonuniform electric field at the surface of a zinc (Zn) anode, coupled with water-induced parasitic reactions, exacerbates the growth of Zn dendrites, presenting a significant impediment to large-scale energy storage in aqueous Zn-ion batteries. One of the most convenient strategies for mitigating dendrite-related issues involves controlling crystal growth through electrolyte additives. Herein, we present thiamine hydrochloride (THC) as an electrolyte additive capable of effectively stabilizing the preferential deposition of the Zn(002) plane. First-principles calculations reveal that THC tends to adsorb on Zn(100) and Zn(101) planes and is capable of inducing the deposition of Zn ion onto the (002) plane and the preferential growth of the (002) plane, resulting in a flat and compact deposition layer. A THC additive not only effectively suppresses dendrite growth but also prevents the generation of side reactions and hydrogen evolution reaction. Consequently, the Zn||Zn symmetric battery exhibits long-term cycling stability of over 3000 h at 1 mA cm-2/1 mAh cm-2 and 1000 h at 10 mA cm-2/10 mAh cm-2. Furthermore, the NH4V4O10||Zn full battery also displays excellent cycling stability and a high reversible capacity of 210 mAh g-1 after 1000 cycles at 1 A g-1, highlighting a significant potential for practical applications.

10.
J Colloid Interface Sci ; 661: 91-101, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38295706

RESUMO

A high-temperature-resistance insulating layer with high thermal conductivity is the key component for fabricating the instant metal-based electric heating tube. However, it is still a challenge for materials to possess excellent high-temperature resistance, superior insulating property, and high thermal conductivity at the same time. Here, a novel SiO2 bridged AlN/MSR composite based on methylphenyl silicone resin (MSR) and AlN filler was reported. MSR with a high thermal decomposition temperature of 452.0 °C and a high withstand voltage of 5.6 kV was first synthesized by adjusting the contents of alkyl and phenyl groups. The superior high-temperature resistant insulating property is 3.7 and 2.4 times higher than the national standard requirement of 1.5 kV and commercial silicone resin, respectively. The hydrogen bonds formed between SiO2, AlN, and MSR and the electrostatic adsorption between SiO2 and AlN can remarkably improve the uniform dispersion of AlN in MSR and thus enhance the insulating property, thermal conductivity, and thermal stability. With the addition of 2 wt% SiO2 and 50 wt% AlN, the SiO2-AlN/MSR composite exhibits an extremely high withstand voltage of 7.3 kV, a high thermal conductivity of 0.553 W·m-1·K-1, and an enhanced decomposition temperature of 475 °C. The superior insulating property and thermal conductivity are 4.9 and 1.3 times higher than the national standard requirement and pure MSR, respectively. This novel composite shows great potential for application in the fields requiring integrated superior insulating property, high-temperature resistance, and high thermal conductivity.

11.
Zhongguo Gu Shang ; 37(6): 5465-52, 2024 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-38910375

RESUMO

OBJECTIVE: To explore clinical efficacy of osteoplasty combined with percutaneous vertebroplasty(PVP) and percutaneous kyphoplasty (PKP) alone in treating osteoporosis vertebral compression fractures (OVCFs). METHODS: The clinical data of 80 patients with single-level OVCFs treated from January 2021 to June 2022 were retrospectively analyzed, and were divided into treatment group and control group according to different surgical methods, 40 patients in each group. In treatment group, there were 24 males and 16 females, aged from 60 to 83 years old with an average of (70.43±7.31) years old;bone mineral density ranged from -3.30 to -2.50 SD with an average of(-2.84±0.24) SD;1 patient with T10, 4 patients with T11, 11 patients with T12, 7 patients with L1, 7 patients with L2, 5 patients with L3, 3 patients with L4, 2 patients with L5;bone setting technique combined with PVP were performed. In control group, there were 27 males and 13 females, aged from 60 to 82 years old with an average of (68.98±6.94) years old;bone mineral density ranged from -3.40 to -2.50 SD with an average of (-2.76±0.23) SD;2 patients with T10, 3 patients with T11, 13 patients with T12, 11 patients with L1, 5 patients with L2, 3 patients with L3, 2 patients with L4, 1 patient with L5;simple PKP were peformed. Visual analogue scale (VAS) and lumbar Oswestry disability index (ODI) were compared between two groups before operation, 3 days, 3 and 12 months after operation. The changes of local kyphotic angle, vertebral wedge angle and vertebral anterior margin height ratio were compared between two groups before operation, 3 days and 12 months after operation. RESULTS: All patients were successfully completed operation. Treatment group were followed up from 13 to 22 months with an average of (16.82±2.14) months, and control group were followed up from 13 to 23 months with an average of (16.45±2.56) months. Three patients were occurred bone cement leakage in treatment group, while 1 patient were occurred bone cement leakage and 1 patient occurred sensory disturbance of lower limb skin in control group;there were no significant difference in complications between two groups (P>0.05). There were no significant difference in preoperative VAS and ODI between two groups (P>0.05). At 3 days after operation, VAS of treatment group 3.68±0.62 was significantly higher than that of control group 4.00±0.72 (P<0.05). There were no significant difference in VAS and ODI between two groups at 3 and 12 months after operation (P>0.05). There were no significant difference in local kyphotic angle, vertebral wedge angle and vertebral anterior margin height between two groups at 3 days and 12 months after operation (P>0.05). CONCLUSION: Compared with PKP, bone setting manipulation combined with PVP for the treatment of OVCFs has advantages in early postoperative pain relief. In terms of vertebral height recovery, bone setting manipulation combined with PVP and PKP alone have similar clinical effects.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Humanos , Feminino , Masculino , Idoso , Fraturas por Compressão/cirurgia , Pessoa de Meia-Idade , Cifoplastia/métodos , Vertebroplastia/métodos , Idoso de 80 Anos ou mais , Fraturas da Coluna Vertebral/cirurgia , Fraturas por Osteoporose/cirurgia , Estudos Retrospectivos
12.
ACS Appl Mater Interfaces ; 16(39): 52842-52855, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39172509

RESUMO

The threat posed by biological and chemical warfare agents (BCWA) to national security, the environment, and personal health underscores the need for innovative chemical protective clothing. To address the limitations of conventional activated carbon materials, which are prone to falling off and adsorption saturation, an efficient self-association approach was introduced. In this study, we proposed the immobilization of metal-organic framework (MOF) 808 and Ag nanoparticles onto a polypropylene (PP) fiber membrane using a rapid self-association method facilitated by chitosan (CS). The MOF 808/Ag-based (PP-CS/808-Ag) fiber membrane demonstrated exceptional degradation efficiency, achieving a remarkable rate of t1/2 within 2 h for the mustard simulant 2-chloroethyl ethyl sulfide (2-CEES) and a rate of t1/2 = 4.12 min for the G-series simulant dimethyl 4-nitrophenylphosphate (DMNP). A theoretical computational model was developed to determine the overall reaction mechanism, and it was verified that MOF 808 and Ag nanoparticles were mainly involved in the hydrolysis process against 2-CEES and DMNP. The PP-CS/808-Ag composite fiber film was prepared as the core layer, and the fracture strength, bending resistance, and moisture permeability were better than those specified by many countries for biochemical protective clothing, showing that it has a broad application prospect in developing a generation of broad-spectrum bioprotective clothing.

13.
Int J Biol Macromol ; 279(Pt 1): 134929, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39179078

RESUMO

Laccases with highly catalytic properties have been widely used in developing green applications for water remediation. However, the poor stability and low reutilization rate of free laccase make it difficult to be applied practically. Hence, in this study, an immobilized laccase was prepared using dopamine (DA) functionalized sodium alginate (SA)/polyethylene glycol (PEG) composite hydrogels to realize the recyclability of the laccase. The SA/PEG composite hydrogels, as the protective carrier for laccase, exhibited excellent catalytic stability in various interfering environments. After 30 days, Lac@SA-PDA/PEG beads could remain 70.23 % of the initial activity, as the residual activity of free laccase was only 12.35 %. When free laccase and Lac@SA-PDA/PEG beads were used for decolorization of Reactive Blue 19 (RB-19,100 mg/L), the degradation rate of Lac@SA-PDA/PEG is 6.88 times higher than free laccase. More importantly, the SA-PDA/PEG composite hydrogel exhibited a high reutilization rate, which after six cycles, Lac@SA-PDA/PEG beads retained 90.23 % of its initial activity. Besides, the degradation effect of Lac@SA-PDA/PEG on different dyes was analyzed. In addition, the conjectured degradation pathways of RB-19 by laccase were analyzed. The work showed that immobilized laccase has tremendous potential for the treatment of dyestuff wastewater.


Assuntos
Alginatos , Corantes , Dopamina , Enzimas Imobilizadas , Hidrogéis , Lacase , Polietilenoglicóis , Águas Residuárias , Lacase/química , Lacase/metabolismo , Alginatos/química , Hidrogéis/química , Enzimas Imobilizadas/química , Polietilenoglicóis/química , Águas Residuárias/química , Corantes/química , Dopamina/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
14.
J Colloid Interface Sci ; 669: 137-145, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38713953

RESUMO

Iron sulfides have shown great potential as anode materials for sodium-ion batteries (SIBs) because of their high sodium storage capacity and low cost. Nevertheless, iron sulfides generally exhibit unsatisfied electrochemical performance induced by sluggish electron/ion transfer and severe pulverization upon the sodiation/desodiation process. Herein, we constructed a yolk-shell FeS@NC nanosphere with an N-doped carbon shell and FeS particle core via a simple hydrothermal method, followed by in-situ polymerization and vulcanization. The FeS particles intimately coupled with N-doped carbon can accelerate the electron transfer, avoid severe volume expansion, and maintain structural stability upon repeated sodiation/desodiation process. Furthermore, the small particle size of FeS can shorten ion-diffusion distance and facilitate ion transportation. Therefore, the FeS@NC nanosphere shows excellent cycling performance and superior rate capability that it can deliver a high capacity of 520.1 mAh g-1 over 800 cycles at 2.0 A g-1 and a remarkable capacity of 625.9 mAh g-1 at 10.0 A g-1.

15.
Virol Sin ; 38(5): 801-812, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37419417

RESUMO

Severe infections caused by multidrug-resistant Klebsiella pneumoniae (K. pneumoniae) highlight the need for new therapeutics with activity against this pathogen. Phage therapy is an alternative treatment approach for multidrug-resistant K. pneumoniae infections. Here, we report a novel bacteriophage (phage) BUCT631 that can specifically lyse capsule-type K1 K. pneumoniae. Physiological characterization revealed that phage BUCT631 could rapidly adsorb to the surface of K. pneumoniae and form an obvious halo ring, and it had relatively favorable thermal stability (4-50 â€‹°C) and pH tolerance (pH â€‹= â€‹4-12). In addition, the optimal multiplicity of infection (MOI) of phage BUCT631 was 0.01, and the burst size was approximately 303 â€‹PFU/cell. Genomic analysis showed that phage BUCT631 has double-stranded DNA (total length of 44,812 bp) with a G â€‹+ â€‹C content of 54.1%, and the genome contains 57 open reading frames (ORFs) and no virulence or antibiotic resistance related genes. Based on phylogenetic analysis, phage BUCT631 could be assigned to a new species in the genus Drulisvirus of the subfamily Slopekvirinae. In addition, phage BUCT631 could quickly inhibit the growth of K. pneumoniae within 2 â€‹h in vitro and significantly elevated the survival rate of K. pneumoniae infected Galleria mellonella larvae from 10% to 90% in vivo. These studies suggest that phage BUCT631 has promising potential for development as a safe alternative for control and treatment of multidrug-resistant K. pneumoniae infection.


Assuntos
Bacteriófagos , Infecções por Klebsiella , Mariposas , Animais , Bacteriófagos/genética , Klebsiella pneumoniae/genética , Larva , Filogenia , Infecções por Klebsiella/terapia
16.
Materials (Basel) ; 16(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36984192

RESUMO

In order to explore the evolution mechanism of freeze-thaw disasters and the role of water in the freezing-thawing cycles of rocks, the macro mechanical indexes and microstructural characteristics of seven different saturation sandstones after certain freeze-thaw cycles were analyzed. Electron microscope scanning, nuclear magnetic resonance, and uniaxial compression tests were employed to study the migration law of water in the rock, the crack growth law, and the damage mechanism during freeze-thaw cycles. The results showed that when the saturation was 85%, the peak load curve of sandstone with different saturation appeared at the minimum point, and the porosity of sandstone reached the maximum. The damage variable increased sharply when the saturation was 75-85%. This proves that 85% saturation is the critical value of sandstone after five freeze-thaw cycles. The water migration freezing model is established, and the migration direction of capillary film water during freezing is micropore → mesopore → macropore. The migration of water is accompanied by the expansion and generation of cracks. Then we study the mechanism and law of crack expansion, and the crack propagation rate is positively related to the theoretical suction. The theoretical suction and theoretical ice pressure increased linearly with the decrease in temperature, which accelerated the crack propagation. The crack propagation rate in decreasing order is Vmacropore > Vmesopore > Vmicropore. The research results can provide a theoretical basis for evaluating the stability of rocks under the action of freeze-thaw cycles in cold regions.

17.
Microbiol Spectr ; 11(1): e0403022, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36700630

RESUMO

In recent years, Stenotrophomonas maltophilia (S. maltophilia) has become an important pathogen of clinically acquired infections accompanied by high pathogenicity and high mortality. Moreover, infections caused by multidrug-resistant S. maltophilia have emerged as a serious challenge in clinical practice. Bacteriophages are considered a promising alternative for the treatment of S. maltophilia infections due to their unique antibacterial mechanism and superior bactericidal ability compared with traditional antibiotic agents. Here, we reported a new phage BUCT700 that has a double-stranded DNA genome of 43,214 bp with 70% GC content. A total of 55 ORFs and no virulence or antimicrobial resistance genes were annotated in the genome of phage BUCT700. Phage BUCT700 has a broad host range (28/43) and can lyse multiple ST types of clinical S. maltophilia (21/33). Furthermore, bacteriophage BUCT700 used the Type IV fimbrial biogenesis protein PilX as an adsorption receptor. In the stability test, phage BUCT700 showed excellent thermal stability (4 to 60°C) and pH tolerance (pH = 4 to 12). Moreover, phage BUCT700 was able to maintain a high titer during long-term storage. The adsorption curve and one-step growth curve showed that phage BUCT700 could rapidly adsorb to the surface of S. maltophilia and produce a significant number of phage virions. In vivo, BUCT700 significantly increased the survival rate of S. maltophilia-infected Galleria mellonella (G. mellonella) larvae from 0% to 100% within 72 h, especially in the prophylactic model. In conclusion, these findings indicate that phage BUCT700 has promising potential for clinical application either as a prophylactic or therapeutic agent. IMPORTANCE The risk of Stenotrophomonas maltophilia infections mediated by the medical devices is exacerbated with an increase in the number of ICU patients during the Corona Virus Disease 2019 (COVID-19) epidemic. Complications caused by S. maltophilia infections could complicate the state of an illness, greatly extending the length of hospitalization and increasing the financial burden. Phage therapy might be a potential and promising alternative for clinical treatment of multidrug-resistant bacterial infections. Here, we investigated the protective effects of phage BUCT700 as prophylactic and therapeutic agents in Galleria mellonella models of infection, respectively. This study demonstrates that phage therapy can provide protection in targeting S. maltophilia-related infection, especially as prophylaxis.


Assuntos
Bacteriófagos , COVID-19 , Mariposas , Stenotrophomonas maltophilia , Animais , Humanos , Bacteriófagos/genética , Bacteriófagos/metabolismo , Stenotrophomonas maltophilia/genética , Larva/microbiologia , Antibacterianos/farmacologia
18.
Viruses ; 15(3)2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36992382

RESUMO

Acinetobacter baumannii (A. baumannii) is one of the most common clinical pathogens and a typical multi-drug resistant (MDR) bacterium. With the increase of drug-resistant A. baumannii infections, it is urgent to find some new treatment strategies, such as phage therapy. In this paper, we described the different drug resistances of A. baumannii and some basic properties of A. baumannii phages, analyzed the interaction between phages and their hosts, and focused on A. baumannii phage therapies. Finally, we discussed the chance and challenge of phage therapy. This paper aims to provide a more comprehensive understanding of A. baumannii phages and theoretical support for the clinical application of A. baumannii phages.


Assuntos
Acinetobacter baumannii , Bacteriófagos , Antibacterianos
19.
ACS Appl Mater Interfaces ; 14(8): 10457-10466, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35175738

RESUMO

The rational electrode design is one of the most important ways to enhance the electrochemical properties of lithium-sulfur batteries (LSBs). In this contribution, we use Ni-embedded porous graphitic carbon fiber (PGCF@Ni) as the scaffold to construct a novel cathode and anode for LSBs. With the help of elaborate surface engineering, the constructed solid electrolyte interface (SEI)@Li/PGCF@Ni anodes can effectively restrain the growth of lithium dendrites during the cycle, exhibiting an ultralow overpotential of ∼10 mV for 2000 h at 1 mA cm-2/1 mA h cm-2. The underlying mechanism is further investigated by COMSOL Multiphysics simulations. Additionally, the PGCF@Ni/S cathode fabricated by the molten sulfurizing method manifests superior rate performance and stability. Ultimately, the assembled SEI@Li/PGCF@Ni||PGCF@Ni/S full battery exhibits prominent electrochemical property with a high capacity retention of about 77.9% after 600 cycles at 1 C. Such success at the performance improvement in LSBs may open up avenues toward other rational designs of high-quality electrodes in electrochemical energy storage.

20.
Front Microbiol ; 13: 906961, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35865914

RESUMO

Stenotrophomonas maltophilia (S. maltophilia) is a common opportunistic pathogen that is resistant to many antibiotics. Bacteriophages are considered to be an effective alternative to antibiotics for the treatment of drug-resistant bacterial infections. In this study, we isolated and characterized a phage, BUCT603, infecting drug-resistant S. maltophilia. Genome sequencing showed BUCT603 genome was composed of 44,912 bp (32.5% G + C content) with 64 predicted open reading frames (ORFs), whereas no virulence-related genes, antibiotic-resistant genes or tRNA were identified. Whole-genome alignments showed BUCT603 shared 1% homology with other phages in the National Center for Biotechnology Information (NCBI) database, and a phylogenetic analysis indicated BUCT603 can be classified as a new member of the Siphoviridae family. Bacteriophage BUCT603 infected 10 of 15 S. maltophilia and used the TonB protein as an adsorption receptor. BUCT603 also inhibited the growth of the host bacterium within 1 h in vitro and effectively increased the survival rate of infected mice in a mouse model. These findings suggest that bacteriophage BUCT603 has potential for development as a candidate treatment of S. maltophilia infection.

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