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1.
ACS Infect Dis ; 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735064

RESUMO

Glucose is widely used in the reconstitution of intravenous medications, which often include antimicrobials. How glucose affects antimicrobial activity has not been comprehensively studied. The present work reports that glucose added to bacteria growing in a rich medium suppresses the bactericidal but not the bacteriostatic activity of several antimicrobial classes, thereby revealing a phenomenon called glucose-mediated antimicrobial tolerance. Glucose, at concentrations corresponding to blood-sugar levels of humans, increased survival of Escherichia coli treated with quinolones, aminoglycosides, and cephalosporins with little effect on minimal inhibitory concentration. Glucose suppressed a ROS surge stimulated by ciprofloxacin. Genes involved in phosphorylated fructose metabolism contributed to glucose-mediated tolerance, since a pfkA deficiency, which blocks the formation of fructose-1,6-bisphosphate, eliminated protection by glucose. Disrupting the pentose phosphate pathway or the TCA cycle failed to alter glucose-mediated tolerance, consistent with an upstream involvement of phosphorylated fructose. Exogenous sodium pyruvate or sodium citrate reversed glucose-mediated antimicrobial tolerance. Both metabolites bypass the effects of fructose-1,6-bisphosphate, a compound known to scavenge hydroxyl radical and chelate iron, activities that suppress ROS accumulation. Treatment with these two compounds constitutes a novel way to mitigate the glucose-mediated antimicrobial tolerance that may exist during intravenous antimicrobial therapy, especially for diabetes patients.

2.
J Appl Toxicol ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700028

RESUMO

This study demonstrated that both copper oxide nanoparticles (CuO-NPs) and copper nanoparticles (Cu-NPs) can cause swelling, inflammation, and cause damage to the mitochondria of alveolar type II epithelial cells in mice. Cellular examinations indicated that both CuO-NPs and Cu-NPs can reduce cell viability and harm the mitochondria of human bronchial epithelial cells, particularly Beas-2B cells. However, it is clear that CuO-NPs exhibit a more pronounced detrimental effect compared with Cu-NPs. Using bafilomycin A1 (Bafi A1), an inhibitor of lysosomal acidification, was found to enhance cell viability and alleviate mitochondrial damage caused by CuO-NPs. Additionally, Bafi A1 also reduces the accumulation of dihydrolipoamide S-acetyltransferase (DLAT), a marker for mitochondrial protein toxicity, induced by CuO-NPs. This observation suggests that the toxicity of CuO-NPs depends on the distribution of copper particles within cells, a process facilitated by the acidic environment of lysosomes. The release of copper ions is thought to be triggered by the acidic conditions within lysosomes, which aligns with the lysosomal Trojan horse mechanism. However, this association does not seem to be evident with Cu-NPs.

3.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1526-1539, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621936

RESUMO

This study aims to investigate the component variations and spatial distribution of ginsenosides in Panax quinquefolium roots during repeated steaming and drying. Ultra performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS/MS) was employed to identify the ginsenosides in the root extract. Matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI) was employed to visualize the spatial distribution and spatiotemporal changes of prototype ginsenosides and metabolites in P. quinquefolium roots. The UPLC results showed that 90 ginsenosides were identified during the steaming process of the roots, and polar ginsenosides were converted into low polar or non-polar ginsenosides. The content of prototype ginsenosides decreased, while that of rare ginsenosides increased, which included 20(S/R)-ginsenoside Rg_3, 20(S/R)-ginsenoside Rh_2, and ginsenosides Rk_1, Rg_5, Rs_5, and Rs_4. MALDI-MSI results showed that ginsenosides were mainly distributed in the epidermis and phloem. As the steaming times increased, ginsenosides were transported to the xylem and medulla. This study provides fundamental information for revealing the changes of biological activity and pharmacological effect of P. quinquefolium roots that are caused by repeated steaming and drying and gives a reference for expanding the application scope of this herbal medicine.


Assuntos
Ginsenosídeos , Panax , Ginsenosídeos/análise , Espectrometria de Massas em Tandem , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Panax/química , Cromatografia Líquida de Alta Pressão/métodos , Raízes de Plantas/química
4.
World J Psychiatry ; 14(2): 315-329, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38464778

RESUMO

BACKGROUND: Sleep deprivation is a prevalent issue that impacts cognitive function. Although numerous neuroimaging studies have explored the neural correlates of sleep loss, inconsistencies persist in the reported results, necessitating an investigation into the consistent brain functional changes resulting from sleep loss. AIM: To establish the consistency of brain functional alterations associated with sleep deprivation through systematic searches of neuroimaging databases. Two meta-analytic methods, signed differential mapping (SDM) and activation likelihood estimation (ALE), were employed to analyze functional magnetic resonance imaging (fMRI) data. METHODS: A systematic search performed according to PRISMA guidelines was conducted across multiple databases through July 29, 2023. Studies that met specific inclu-sion criteria, focused on healthy subjects with acute sleep deprivation and reported whole-brain functional data in English were considered. A total of 21 studies were selected for SDM and ALE meta-analyses. RESULTS: Twenty-one studies, including 23 experiments and 498 subjects, were included. Compared to pre-sleep deprivation, post-sleep deprivation brain function was associated with increased gray matter in the right corpus callosum and decreased activity in the left medial frontal gyrus and left inferior parietal lobule. SDM revealed increased brain functional activity in the left striatum and right central posterior gyrus and decreased activity in the right cerebellar gyrus, left middle frontal gyrus, corpus callosum, and right cuneus. CONCLUSION: This meta-analysis consistently identified brain regions affected by sleep deprivation, notably the left medial frontal gyrus and corpus callosum, shedding light on the neuropathology of sleep deprivation and offering insights into its neurological impact.

5.
Heliyon ; 10(6): e27956, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38515703

RESUMO

Despite existing evidence linking dyskinesia to levodopa, the primary treatment for Parkinson's, the dose-response relationship and risk factors remain uncertain. In this study, the risk for dyskinesia in patients with Parkinson's disease receiving levodopa was evaluated via meta-analysis and meta-regression approaches to examine dyskinesia risk factors more reliably and improve treatment strategies and patient care. The PubMed and Embase databases were searched to identify randomized controlled trials comparing levodopa with other anti-Parkinson's drugs published in English before June 31, 2023. The primary outcome was dyskinesia, and a risk of bias assessment was performed. In total, 24 studies met the inclusion criteria; 21 had a low risk of bias, and 3 had a high risk of bias. These studies included 4698 patients with Hoehn and Yahr Grade I-III Parkinson's disease. Our meta-analysis showed that the risk of dyskinesia was higher for levodopa than for other anti-Parkinson's drugs (odds ratio: 2.52 [95% confidence interval: 1.84-3.46]). Dyskinesia was not related to age (slope coefficient: 0.185 [0.095]; P = 0.061), disease duration (slope coefficient: 0.011 [0.018]; P = 0.566), or treatment duration (slope coefficient: 0.008 [0.007]; P = 0.216). The mean levodopa equivalent dose (slope coefficient: 0.004 [0.001]; P = 0.001) in the experimental group and the differences in drug doses between the experimental and control groups were correlated with the risk of dyskinesia. Results of randomized controlled trials supported an association between the levodopa dose and dyskinesia in patients with Parkinson's disease. Compared with levodopa users, users of other anti-Parkinson's drugs had a lower incidence of dyskinesia. Age, disease duration, and treatment duration were not correlated with dyskinesia. These findings suggest that anti-Parkinson's drugs other than levodopa, particularly in cases of early-stage Parkinson's disease, should be considered to reduce the risk of dyskinesia.

6.
Microbiol Spectr ; 11(6): e0097523, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37815335

RESUMO

IMPORTANCE: The type 3 secretion system (T3SS) was obtained in many Gram-negative bacterial pathogens, and it is crucial for their pathogenesis. Environmental signals were found to be involved in the expression regulation of T3SS, which was vital for successful bacterial infection in the host. Here, we discovered that L-glutamine (Gln), the most abundant amino acid in the human body, could repress enterohemorrhagic Escherichia coli (EHEC) T3SS expression via nitrogen metabolism and therefore had potential as an antivirulence agent. Our in vitro and in vivo evidence demonstrated that Gln could decline EHEC infection by attenuating bacterial virulence and enhancing host defense simultaneously. We repurpose Gln as a potential treatment for EHEC infection accordingly.


Assuntos
Escherichia coli Êntero-Hemorrágica , Infecções por Escherichia coli , Proteínas de Escherichia coli , Enteropatias , Humanos , Virulência , Fatores de Virulência/metabolismo , Glutamina/metabolismo , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/microbiologia , Sistemas de Secreção Tipo III/metabolismo , Escherichia coli Êntero-Hemorrágica/metabolismo
7.
NPJ Vaccines ; 8(1): 154, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816743

RESUMO

Human Cytomegalovirus (HCMV) is the leading infectious congenital infection globally and the most common viral infection in transplant recipients, therefore identifying a vaccine for HCMV is a top priority. Humoral immunity is a correlate of protection for HCMV infection. The most effective vaccine tested to date, which achieved 50% reduction in acquisition of HCMV, was comprised of the glycoprotein B protein given with an oil-in-water emulsion adjuvant MF59. We characterize gB-specific monoclonal antibodies isolated from individuals vaccinated with a disabled infectious single cycle (DISC) CMV vaccine, V160, and compare these to the gB-specific monoclonal antibody repertoire isolated from naturally-infected individuals. We find that vaccination with V160 resulted in gB-specific antibodies that bound homogenously to gB expressed on the surface of a cell in contrast to antibodies isolated from natural infection which variably bound to cell-associated gB. Vaccination resulted in a similar breadth of gB-specific antibodies, with binding profile to gB genotypes 1-5 comparable to that of natural infection. Few gB-specific neutralizing antibodies were isolated from V160 vaccinees and fewer antibodies had identifiable gB antigenic domain specificity compared to that of naturally-infected individuals. We also show that glycosylation of gB residue N73 may shield binding of gB-specific antibodies.

8.
Zhongguo Zhong Yao Za Zhi ; 48(15): 4208-4214, 2023 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-37802789

RESUMO

In this study, the transmittance of tanshinone Ⅱ_A(Tan Ⅱ_A) and cryptotanshinone(CTS) through the blood-prostate barrier and their distributions in the prostate tissue were compared between tanshinone extract(Tan E) treatment group and the corresponding monomer composition group under the equivalent dose conversion in vitro and in vivo. First, the human prostate epithelial cell line RWPE-1 was cultured in vitro for 21 days for the establishment of a blood-prostate barrier model, and the transmission of Tan Ⅱ_A and CTS through the barrier model was investigated after administration of Tan E and corresponding single active components. Second, SD rats were administrated with 700 mg·kg~(-1) Tan E, 29 mg·kg~(-1) CTS, and 50 mg·kg~(-1) Tan Ⅱ_A by gavage, and plasma and prostate tissue samples were collected at the time points of 2, 4, 8, 12, and 24 h. The Tan Ⅱ_A and CTS concentrations in the samples were determined. The results showed that in the cell model, the cumulative transmission amounts of CTS and Tan Ⅱ_A in the extract at each time point were higher than those of the corresponding single active components(P<0.01). In rats, after the administration of Tan E, the concentrations of Tan Ⅱ_A and CTS in rat plasma and prostate were higher than those of the corresponding single active components. This study demonstrated that the coexisting components in Tan E promoted the penetration of its main pharmacological components Tan Ⅱ_A and CTS through the blood-prostate barrier. The findings provide a theoretical and experimental basis for the application of Tan E in the clinical treatment of prostate-related diseases.


Assuntos
Abietanos , Próstata , Masculino , Ratos , Humanos , Animais , Ratos Sprague-Dawley , Abietanos/farmacologia , Permeabilidade
9.
Viruses ; 15(10)2023 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-37896813

RESUMO

Despite the success of rotavirus vaccines, rotaviruses remain one of the leading causes of diarrheal diseases, resulting in significant childhood morbidity and mortality, especially in low- and middle-income countries. The reverse genetics system enables the manipulation of the rotavirus genome and opens the possibility of using rotavirus as an expression vector for heterologous proteins, such as vaccine antigens and therapeutic payloads. Here, we demonstrate that three positions in rotavirus genome-the C terminus of NSP1, NSP3 and NSP5-can tolerate the insertion of reporter genes. By using rotavirus expressing GFP, we develop a high-throughput neutralization assay and reveal the pre-existing immunity against rotavirus in humans and other animal species. Our work shows the plasticity of the rotavirus genome and establishes a high-throughput assay for interrogating humoral immune responses, benefiting the design of next-generation rotavirus vaccines and the development of rotavirus-based expression platforms.


Assuntos
Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Humanos , Animais , Criança , Rotavirus/fisiologia , Vacinas contra Rotavirus/genética , Genética Reversa/métodos , Genes Reporter
10.
Lancet Infect Dis ; 23(12): 1383-1394, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37660711

RESUMO

BACKGROUND: A vaccine that prevents cytomegalovirus (CMV) infection in women could reduce the incidence of congenital CMV infection, a major cause of neurodevelopmental disability. We aimed to assess the safety and efficacy of a replication-defective investigational CMV vaccine, V160, in CMV-seronegative women. METHODS: This phase 2b, randomised, double-blind, placebo-controlled study was conducted at 90 sites in seven countries (USA, Finland, Canada, Israel, Spain, Russia, and Australia). Eligible participants were generally healthy, CMV-seronegative, non-pregnant, 16-35-year-old women of childbearing potential with exposure to children aged 5 years or younger. Participants were randomly assigned using central randomisation via an interactive response technology system 1:1:1 to one of three groups: V160 three-dose regimen (V160 at day 1, month 2, and month 6), V160 two-dose regimen (V160 on day 1, placebo at month 2, and V160 at month 6), or placebo (saline solution at day 1, month 2, and month 6). The primary outcomes were the efficacy of three doses of V160 in reducing the incidence of primary CMV infection during the follow-up period starting 30 days after the last dose of vaccine using a fixed event rate design, and the safety and tolerability of the two-dose and three-dose V160 regimens. We planned to test the efficacy of a two-dose regimen of V160 in reducing the incidence of primary CMV infection only if the primary efficacy hypothesis was met. Analyses for the primary efficacy endpoint were performed on the per-protocol efficacy population; safety analyses included all randomly assigned participants who received study vaccine. The primary efficacy hypothesis was tested at prespecified interim and final analyses. The study was ongoing and efficacy data continued to accrue at the time of final testing of the primary efficacy hypothesis. Vaccine efficacy was re-estimated after final testing of the primary efficacy hypothesis based on all available efficacy data at end of study. This trial is registered at ClinicalTrials.gov (NCT03486834) and EudraCT (2017-004233-86) and is complete. FINDINGS: Between April 30, 2018, and Aug 30, 2019, 7458 participants were screened, of whom 2220 were randomly assigned to the V160 three-dose group (n=733), V160 two-dose group (n=733), or placebo group (n=734). A total of 523 participants in the V160 three-dose group and 519 in the placebo group were included in the final hypothesis testing. Of these, there were 11 cases of CMV infection in the V160 three-dose group and 20 cases in the placebo group. The vaccine efficacy for the V160 three-dose group was 44·6% (95% CI -15·2 to 74·8) at the final testing of the primary efficacy hypothesis, a result corresponding to failure to demonstrate the primary efficacy hypothesis. On the basis of this result, the study was terminated for futility. The re-estimate of vaccine efficacy for the V160 three-dose group based on all available efficacy data at end of study (556 participants in the V160 three-dose group and 543 in the placebo group) was 42·4% (95% CI -13·5 to 71·1). A total of 728 participants in the V160 three-dose group, 729 in the V160 two-dose group, and 732 in the placebo group were included in the safety analyses. The most common solicited injection-site adverse event was injection-site pain (680 [93%] in the V160 three-dose group, 659 [90%] in the V160 two-dose group, and 232 [32%] in the placebo group). The most common solicited systemic adverse event was fatigue (457 [63%] in the V160 three-dose group, 461 [63%] in the V160 two-dose group, and 357 [49%] in the placebo group). No vaccine-related serious adverse events or deaths were reported. INTERPRETATION: V160 was generally well tolerated and immunogenic; however, three doses of the vaccine did not reduce the incidence of primary CMV infection in CMV-seronegative women compared with placebo. This study provides insights into the design of future CMV vaccine efficacy trials, particularly for the identification of CMV infection using molecular assays. FUNDING: Merck Sharp & Dohme, a subsidiary of Merck & Co, Rahway, NJ, USA (MSD).


Assuntos
Infecções por Citomegalovirus , Vacinas contra Citomegalovirus , Vacinas , Criança , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Citomegalovirus , Imunização , Infecções por Citomegalovirus/prevenção & controle , Método Duplo-Cego , Imunogenicidade da Vacina
11.
Adv Mater ; 35(47): e2304686, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37540488

RESUMO

Solid-state lithium-metal batteries constructed by in-situ solidification of cyclic ether are considered to be a critical strategy for the next generation of solid-state batteries with high energy density and safety. However, the poor thermal/electrochemical stability of linear polyethers and severe interfacial reactions limit its further development. Herein, in-situ ring-opening hybrid crosslinked polymerization is proposed for organic/inorganic hybrid polymer electrolyte (HCPE) with superior ionic conductivity of 2.22 × 10-3 S cm-1 at 30 °C, ultrahigh Li+ transference number of 0.88, and wide electrochemical stability window of 5.2 V. These allow highly stable lithium stripping/plating cycling for over 1000 h at 1 mA cm-2 , which also reveal a well-defined interfacial stabilization mechanism. Thus, HCPE endows assembled solid-state lithium-metal batteries with excellent long-cycle performance over 600 cycles at 2 C (25 °C) and superior capacity retention of 92.1%. More importantly, the proposed noncombustible HCPE opens up a new frontier to promote the practical application of high safety and high energy density solid-state batteries via in-situ solidification.

12.
Front Microbiol ; 14: 1190894, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485509

RESUMO

Background: Evidence from previous studies have implicated an important association between gut microbiota (GM) and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), but whether there is a definite causal relationship between GM and ME/CFS has not been elucidated. Method: This study obtained instrumental variables of 211 GM taxa from the Genome Wide Association Study (GWAS), and mendelian randomization (MR) study was carried out to assess the effect of gut microbiota on ME/CFS risk from UK Biobank GWAS (2076 ME/CFS cases and 460,857 controls). Inverse variance weighted (IVW) was the primary method to analyze causality in this study, and a series of sensitivity analyses was performed to validate the robustness of the results. Results: The inverse variance weighted (IVW) method indicated that genus Paraprevotella (OR:1.001, 95%CI:1.000-1.003, value of p < 0.05) and Ruminococca- ceae_UCG_014 (OR 1.003, 95% CI 1.000 to 1.005, value of p < 0.05) were positively associated with ME/CFS risk. Results from the weighted median method supported genus Paraprevotella (OR 1.003, 95% CI 1.000 to 1.005, value of p < 0.05) as a risk factor for ME/CFS. Conclusion: This study reveals a causal relationship between genus paraprevotella, genus Ruminococcaceae_UCG_014 and ME/CFS, and our findings provide novel insights for further elucidating the developmental mechanisms mediated by the gut microbiota of ME/CFS.

13.
Nat Prod Res ; : 1-6, 2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37424239

RESUMO

Sphagnum palustre L. is a Chinese herbal medicine with a long history, however, few studies have been performed on its chemical composition and active effects. In this study, we investigated the composition and antibacterial and antioxidant capacities of extracts obtained from Sphagnum palustre L. phytosomes extracted with conventional solvents (water, methanol, and ethanol) and two different hydrogen bond donors (citric acid and 1,2-propanediol) modified with choline chloride-type deep eutectic solvents (DESs). The results show that Sphagnum palustre extracts contained 253 compounds, including citric acid, ethyl maltol, and thymol. The highest total phenolic content (TPC) was obtained with a DES extraction method combining 1,2-propanediol and choline chloride (39.02 ± 7.08 mg gallic acid equivalent/g dried weight (DW). This shows the composition of Sphagnum palustre as a natural product and the application of DESs in the extraction of active ingredients, demonstrating the potential of peat moss extracts in cosmetics and health products.

14.
Food Chem Toxicol ; 179: 113952, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37481226

RESUMO

Black Phosphorus Quantum Dots (BP-QDs) have potential applications in biomedicine. BP-QDs may enter the body through the respiratory tract during grinding and crushing production and processing, causing respiratory toxicity. Ferroptosis is an oxidative, iron-dependent form of cell death. Here, respiratory toxicity of BP-QDs has been validated in mice and human bronchial epithelial cells. After 24 h of exposure to different doses (4-32 µg/mL) of BP-QDs, intracellular lipid peroxidation and iron overload occurred in Beas-2B cells. After 4 times exposures by noninvasive tracheal instillation at four doses [0, 0.25, 0.5 and 1 (mg/kg/48h)], all animals were sacrificed, organs were removed, processed for pathological examination and molecular analysis. Iron overload, glutathione (GSH) depletion and lipid peroxidation in the lung tissue of mice in the exposure group. Furthermore, based on the ferroptosis-associated protein and mRNA expression, it was hypothesized that BP-QDs induced ferroptosis through increasing intracellular free iron and polyunsaturated fatty acid synthesis. By comparing with previous studies, we speculate that primary cells generally are more sensitive to BP-QDs-induced damage than cancer cells. In summary, findings in the present study confirmed that BP-QDs induce ferroptosis via increasing lipid peroxidation and iron accumulation in vitro and in vivo.


Assuntos
Ferroptose , Sobrecarga de Ferro , Pontos Quânticos , Camundongos , Humanos , Animais , Peroxidação de Lipídeos , Ferroptose/fisiologia , Fósforo , Ferro/metabolismo , Pulmão/metabolismo
15.
J Dent ; 135: 104569, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37263409

RESUMO

BACKGROUND: Glass ionomer cement (GIC) is a commonly used restorative material in dentistry, but GIC does not have significant antibiofilm effects and its mechanical strength is limited. OBJECTIVE: To investigate the antibiofilm and mechanical properties of a newly developed silver nanowire (AgNW) modified GIC. METHODS: GICs were modified with different nanosilver formulations including 0.05%wt AgNW, 0.5%wt AgNW, 0.05%wt silver nanoparticle (AgNP) and 0.5%wt AgNP. Biofilms of Streptococcus mutans were cultured for 72 h on GIC specimens. Scanning electron microscopy (SEM) was conducted to observe the accumulation and morphology of Streptococcus mutans on the material surfaces. Another set of biofilm/specimens was treated with SYTO-9 and the biofilm development was evaluated by quantifying the visible stain with an inverted fluorescence microscope. The compressive strength of the specimens was assessed according to ISO 9917-1:2007. The colour of GICs was compared using the VITA Easyshade system. RESULTS: SEM images showed that fewer biofilms were accumulated on nanosilver-modified GICs. The Streptococcus mutans quantity was significantly lower in all nanosilver-modified groups compared to conventional GIC (p<0.0001). GIC modified with 0.5% AgNP showed slightly lower compressive strength than the negative control (58.3 ± 12.9 MPa vs 78.3 ± 13.8 MPa); but there is no significant difference between all study groups. The colour change between AgNW-modified GIC and conventional GIC was significantly lower than that between AgNP-modified GIC and conventional GIC. CONCLUSION: AgNW-modified GIC showed superior antibiofilm effect and comparable compressive strength to conventional GIC. In addition, the complement of AgNW would not influence the colour stability of GIC as much as AgNP. CLINICAL SIGNIFICANCE: This study developed a novel AgNW-modified GIC material. It showed good antibiofilm and mechanical properties and would not influence the colour stability of GIC. The AgNW-modified GIC has a large potential for clinical use and biomedical application.


Assuntos
Nanopartículas Metálicas , Nanofios , Prata/farmacologia , Cimentos de Ionômeros de Vidro/farmacologia , Teste de Materiais , Biofilmes , Streptococcus mutans
16.
Microbiol Spectr ; 11(4): e0119823, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37310274

RESUMO

Widespread bacterial resistance among Gram-negative bacteria is rapidly depleting our antimicrobial arsenal. Adjuvants that enhance the bactericidal activity of existing antibiotics provide a way to alleviate the resistance crisis, as new antimicrobials are becoming increasingly difficult to develop. The present work with Escherichia coli revealed that neutralized lysine (lysine hydrochloride) enhances the bactericidal activity of ß-lactams in addition to increasing bacteriostatic activity. When combined, lysine hydrochloride and ß-lactam increased expression of genes involved in the tricarboxylic acid (TCA) cycle and raised reactive oxygen species (ROS) levels; as expected, agents known to mitigate bactericidal effects of ROS reduced lethality from the combination treatment. Lysine hydrochloride had no enhancing effect on the lethal action of fluoroquinolones or aminoglycosides. Characterization of a tolerant mutant indicated involvement of the FtsH/HflkC membrane-embedded protease complex in lethality enhancement. The tolerant mutant, which carried a V86F substitution in FtsH, exhibited decreased lipopolysaccharide levels, reduced expression of TCA cycle genes, and reduced levels of ROS. Lethality enhancement by lysine hydrochloride was abolished by treating cultures with Ca2+ or Mg2+, cations known to stabilize the outer membrane. These data, plus damage observed by scanning electron microscopy, indicate that lysine stimulates ß-lactam lethality by disrupting the outer membrane. Lethality enhancement of ß-lactams by lysine hydrochloride was also observed with Acinetobacter baumannii and Pseudomonas aeruginosa, thereby suggesting that the phenomenon is common among Gram-negative bacteria. Arginine hydrochloride behaved in a similar way. Overall, the combination of lysine or arginine hydrochloride and ß-lactam offers a new way to increase ß-lactam lethality with Gram-negative pathogens. IMPORTANCE Antibiotic resistance among Gram-negative pathogens is a serious medical problem. The present work describes a new study in which a nontoxic nutrient increases the lethal action of clinically important ß-lactams. Elevated lethality is expected to reduce the emergence of resistant mutants. The effects were observed with significant pathogens (Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa), indicating widespread applicability. Examination of tolerant mutants and biochemical measurements revealed involvement of endogenous reactive oxygen species in response to outer membrane perturbation. These lysine hydrochloride-ß-lactam data support the hypothesis that lethal stressors can stimulate the accumulation of ROS. Genetic and biochemical work also revealed how an alteration in a membrane protease, FtsH, abolishes lysine stimulation of ß-lactam lethality. Overall, the work presents a method for antimicrobial enhancement that should be safe, easy to administer, and likely to apply to other nutrients, such as arginine.


Assuntos
Lisina , beta-Lactamas , beta-Lactamas/farmacologia , Lisina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Bactérias Gram-Negativas , Escherichia coli/genética , Pseudomonas aeruginosa/genética , Testes de Sensibilidade Microbiana
17.
Polymers (Basel) ; 15(12)2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37376287

RESUMO

FRP (fiber-reinforced polymer)-concrete-steel double-skin square tubular (FCSST) columns are composed of an outside FRP tube, an inside steel tube and the concrete filled between them. Under the continuous constraint of the outside and inside tube, the strain, strength and ductility of concrete are improved significantly compared with those of traditionally reinforced concrete without lateral restraint. Additionally, the outside and inside tube not only function as the permanent formwork in casting but improve the bending and shear resistance of composite columns. Meanwhile, the hollow core also reduces the weight of the structure. Through the compressive testing of 19 FCSST columns subjected to eccentric load, this study focuses on the influence of eccentricity and layers of axial FRP cloth (away from the loading point) on the evolution of axial strain along the cross-section, axial bearing capacity, axial load-lateral deflection curve and other eccentric properties. The results can provide basis and reference for the design and construction of FCSST columns and are of great theoretical significance and practical value for the application of composite columns in the engineering of structures in a corrosive environment and other harsh conditions.

18.
Environ Sci Pollut Res Int ; 30(19): 55255-55277, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36890401

RESUMO

In order to verify how environmental regulation affects the improvement of urban industrial carbon emission efficiency, this study first measures the balanced panel data of industrial carbon emission efficiency of 282 cities in China from 2003 to 2019, and evaluates the direct and regulating impact of environmental regulation on China's urban industrial carbon emission efficiency. Meanwhile, in order to investigate the potential heterogeneity and asymmetry, the panel quantile regression method is used. The empirical results show that (1) during the period 2003-2016, China's overall industrial carbon emission efficiency showed a upward trend, with a decreasing spatial pattern from the east-central-west-northeast region. At the urban scale in China, environmental regulation has a significant direct effect on industrial carbon emission efficiency, which is lagged and heterogeneous. At the low quantiles, a one-period lag in environmental regulation has a negative effect on the improvement of industrial carbon emission efficiency. At the middle and high quantiles, a one-period lag in environmental regulation has a positive effect on the improvement of industrial carbon emission efficiency. Environmental regulation has a moderating effect on industrial carbon efficiency. With increasing industrial emission efficiency, the positive moderating effect of environmental regulation on the relationship between technological progress and industrial carbon emission efficiency shows a pattern of diminishing marginal benefits. The main contribution of this study is the systematic analysis of the potential heterogeneity and asymmetry of the direct and moderating effects of environmental regulation on the industrial carbon emission efficiency at the city scale in China by using panel quantile regression method.


Assuntos
Carbono , Indústrias , China , Cidades , Análise de Sistemas , Desenvolvimento Econômico
19.
J Biomater Appl ; 37(9): 1676-1686, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36879543

RESUMO

The metal gallium holds great promise in the fight against infection by disrupting bacterial iron metabolism through a "Trojan horse" technique. It is well worth trying to investigate the potential for gallium-mediated hydrogels for the treatment of infected wounds. In this paper, Ga3+ is innovatively given an important role in hydrogels based on the conventional multi-component hydrogel with metal ion binding gelation strategy. Thus, Ga@Gel-Alg-CMCs hydrogel with broad-spectrum antimicrobial activity is reported on the treatment of infected wounds. The morphology, degradability, and swelling behavior together indicated the excellent physical properties of this hydrogel. Interestingly, in vivo results also showed favorable biocompatibility, slowing down wound infection and promoting diabetic wound healing, making the gallium-doped hydrogel an ideal antimicrobial dressing.


Assuntos
Anti-Infecciosos , Diabetes Mellitus , Humanos , Hidrogéis/química , Cicatrização , Bandagens , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química
20.
Front Mol Biosci ; 10: 1131402, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36911522

RESUMO

Adrenocortical carcinoma (ACC) has a low incidence but a poor prognosis. And ACC has complex clinical manifestations and limited treatment. Pyroptosis has a dual character and has both positive and negative effects on cancer. However, the role of pyroptosis-related genes (PRGs) in ACC and the impact on ACC progression remains unelucidated. This study performed systematic bioinformatics analysis and basic experimental validation to enable the establishment of prognostic models and demonstrate levels of immune infiltration. Pearson's correlation analysis was used to assess the association of PRGs with tumor immune infiltration, tumor mutation burden (TMB), microsatellite instability (MSI), and immune checkpoints. There 4 PRGs were upregulated, and 25 PRGs were downregulated in ACC. At the same time, we analyzed and reviewed the genetic mutation variation landscape of PRGs. Functional enrichment analysis was also performed to clarify the function of PRGs. Pyroptosis, the inflammatory response, the Toll-like receptor signaling pathway, and the NOD-like receptor signaling pathway are the functions and pathways mainly involved and exerted effects by these 33 PRGs. The results of the prognosis analysis revealed high expression of CASP3, CASP9, GSDMB, GSDMD, NLRC4, PRKACA, and SCAF11 caused a poor survival rate for ACC patients. The above seven PRGs were screened by the optimal λ value of LASSO Cox analysis, and the five selected genes (CASP3, CASP9, GSDMB, GSDMD, NLRC4) were involved in constructing a prognostic PRGs model which enables the overall survival in ACC patients can be predicted with moderate to high accuracy. Prognostic PRGs, especially CASP9, which is the independent factor of ACC prognosis, may be closely correlated with immune-cell infiltration, tumor mutation burden, microsatellite instability, and immune checkpoints. Quantitative Real-Time PCR (qRT-PCR), Western blot and immunohistochemical were performed to validate the mRNA expression levels of CASP9 in adjacent normal tissues and ACC tissues. According to the result of immune checkpoints analysis, NLRC4 and GSDMB may be identified as potential therapeutic targets. In conclusion, we established a prognostic model of PRG characteristics in ACC and analyzed the relationship between PRGs and immune infiltration. Through our study, it may be helpful to find the mechanism of pyroptosis in ACC.

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