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1.
Food Chem ; 462: 141030, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39241685

RESUMO

The human milk fat globule membrane (hMFGM) and Lactobacillus modulate the infant's gut and benefit health. Hence, the current study assesses the probiotic potential of Lactiplantibacillus plantarum (MRK3), Limosilactobacillus ferementum (MK1) isolated from infant feces, and its interaction with hMFGM during conditions mimicking infant digestive tract. Both strains showed high tolerance to gastrointestinal conditions, cell surface hydrophobicity, and strong anti-pathogen activity against Staphylococcus aureus. During digestion, hMFGM significantly exhibited xanthine oxidase activity, membrane roughness, and surface topography. In the presence of hMFGM, survival of MRK3 was higher than MK1, and electron microscopic observation revealed successful entrapment of MRK3 in the membrane matrix throughout digestion. Interestingly, probiotic-membrane matrix interaction showed significant synergy to alleviate oxidative stress and damage induced by cell-free supernatant of Escherichia coli in Caco-2 cells. Our results show that a probiotic-encapsulated membrane matrix potentially opens the functional infant formula development pathway.


Assuntos
Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Leite Humano , Estresse Oxidativo , Probióticos , Humanos , Probióticos/farmacologia , Probióticos/química , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Glicoproteínas/química , Glicoproteínas/farmacologia , Glicoproteínas/metabolismo , Células CACO-2 , Glicolipídeos/química , Glicolipídeos/farmacologia , Glicolipídeos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Leite Humano/química , Lactente , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Fórmulas Infantis/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/metabolismo
2.
J Environ Sci (China) ; 149: 188-199, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181633

RESUMO

Photocatalytic disinfection is an eco-friendly strategy for countering bacterial pollution in aquatic environments. Numerous strategies have been devised to facilitate the generation of reactive oxygen species (ROS) within photocatalysts, ultimately leading to the eradication of bacteria. However, the significance of the physical morphology of photocatalysts in the context of sterilization is frequently obscured, and the progress in the development of physical-chemical synergistic sterilization photocatalysts has been relatively limited. Herein, graphitic carbon nitride (g-C3N4) is chemically protonated to expose more sharp edges. PL fluorescence and EIS results indicate that the protonation can accelerate photogenerated carrier separation and enhance ROS production. Meanwhile, the sharp edges on the protonated g-C3N4 facilitate the physical disruption of cell walls for further promoting oxidative damage. Protonated C3N4 demonstrated superior bactericidal performance than that of pristine g-C3N4, effectively eliminating Escherichia coli within 40 minutes under irradiation. This work highlights the significance of incorporating physical and chemical synergies in photocatalyst design to enhance the disinfection efficiency of photocatalysis.


Assuntos
Desinfecção , Nitrilas , Nitrilas/química , Desinfecção/métodos , Catálise , Escherichia coli/efeitos dos fármacos , Espécies Reativas de Oxigênio , Grafite/química , Esterilização/métodos , Compostos de Nitrogênio/química
3.
Dtsch Med Wochenschr ; 149(19): 1133-1142, 2024 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-39250951

RESUMO

Multi-resistant bacteria such as Escherichia coli and Klebsiella pneumoniae are a growing threat worldwide. The spread of Carbapenemase-producing strains is particularly worrying. New antibiotics and combination therapies offer treatment options, but the development of resistant pathogens remains a major challenge.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana Múltipla , Humanos , Antibacterianos/uso terapêutico , Klebsiella pneumoniae/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia
4.
BMC Oral Health ; 24(1): 1052, 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39245758

RESUMO

BACKGROUND AND OBJECTIVES: Mineral Trioxide Aggregate (MTA) is one of the main retrograde filling materials that is used today as a root end filling material and perforation repair material. This study was conducted with the aim of investigating the antibacterial and antifungal properties of four types of bio-ceramic materials, AGM MTA, Ortho MTA, Pro root MTA and Cem cement for oral and dental health. METHODS: In this study, the antibacterial activity of four types of bio-ceramic materials against two bacterial strains of Enterococcus faecalis (ATTC 29212), Escherichia coli (ATTC 35318) and antifungal activity against Candida albicans (ATTC 10231) were investigated using the well diffusion method. RESULTS: In the context of the relationship between the type of microorganism and the diameter of the growth inhibitory zone for each type of bio-ceramic material, there was no significant difference for Enterococcus faecalis, and a significant difference was observed for Escherichia coli and Candida albicans (p < 0.05). CONCLUSION: The results show that each of the bio-ceramic materials AGM, Pro root, Cem cement and Ortho have antibacterial and antifungal properties. AGM MTA bio-ceramic material on Candida albicans fungus and Ortho MTA bio-ceramic material had the most effect on Escherichia coli bacteria. Therefore, the mentioned bio-ceramic materials can play a significant role in oral and dental health by providing a suitable material for restoration.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Candida albicans , Cerâmica , Combinação de Medicamentos , Enterococcus faecalis , Escherichia coli , Óxidos , Materiais Restauradores do Canal Radicular , Silicatos , Compostos de Cálcio/farmacologia , Silicatos/farmacologia , Candida albicans/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Óxidos/farmacologia , Compostos de Alumínio/farmacologia , Escherichia coli/efeitos dos fármacos , Materiais Restauradores do Canal Radicular/farmacologia , Humanos , Cimentos Dentários/farmacologia , Antibacterianos/farmacologia , Teste de Materiais , Antifúngicos/farmacologia
5.
Curr Microbiol ; 81(11): 350, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39259384

RESUMO

The soil hosts a wide array of bacterial species capable of producing diverse bioactive compounds. This research aimed to screen bacterial isolates for their bioactive potential from extreme environments in Pakistan. Out of the 69 isolates examined, only 7 exhibited antagonistic activity against Bacillus sp. and Escherichia coli test strains. Notably, the B. cereus DS-2 strain demonstrated the highest antibacterial potential (31 mm and 15 mm) against the Bacillus and E. coli test strains, respectively. Mode-of-action studies suggested that the crude extract might have induced morphological abnormalities in the Bacillus sp. (test strain), causing cell contraction, chain breakage, and deformation. Furthermore, the B. cereus DS-2 strain displayed significant antioxidant potential (64.8%) as revealed by the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Thin-layer chromatography (TLC) of the DS-2 crude extract led to the separation of six components, with only spots 3 and 4 exhibiting the antibacterial potential (3 mm and 5 mm, respectively). Subsequently, gas chromatography-mass spectrometry (GC-MS) analysis of the bioactive fraction extracted from TLC revealed the presence of diisooctyl phthalate, dibutyl phthalate, hexadecanoic acid methyl ester, and octadecanoic acid methyl ester. Molecular docking analysis of diisooctyl phthalate and dibutyl phthalate revealed their binding affinity against E. coli and Bacillus sp. targets. ADMET analysis confirmed the solubility, toxicity, and drug-like properties of the ligands based on Lipinski's rule of five. Current findings suggest that these compounds hold promise as antibacterial agents in drug development. This study underscores the diverse microbial community present in extreme environments and highlights the versatile applications of natural products derived from these strains.


Assuntos
Antibacterianos , Antioxidantes , Bacillus , Escherichia coli , Microbiologia do Solo , Paquistão , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Bacillus/metabolismo , Bacillus/isolamento & purificação , Bacillus/química , Bacillus/classificação , Bacillus/genética , Antioxidantes/farmacologia , Antioxidantes/química , Simulação de Acoplamento Molecular , Testes de Sensibilidade Microbiana , Bactérias/efeitos dos fármacos , Bactérias/classificação , Bactérias/metabolismo , Bactérias/genética , Simulação por Computador , Cromatografia Gasosa-Espectrometria de Massas
6.
Sci Rep ; 14(1): 20926, 2024 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251685

RESUMO

Laser texturing seems to be a promising technique for reducing bacterial adhesion on titanium implant surfaces. This work aims to demonstrate the possibility of obtaining a functionally orientated surface of titanium implant elements with a specific architecture with specific bacteriological and photocatalytic properties. Femtosecond laser-generated surface structures, such as laser-induced periodic surface structures (LIPSS, wrinkles), grooves, and spikes on titanium, have been characterised by XRD, Raman spectroscopy, and scanning electron microscopy (SEM). The photocatalytic activity of the titanium surfaces produced was tested based on the degradation effect of methylene blue (MB). The correlation between the photocatalytic activity of TiO2 coatings and their morphology and structure has been analysed. Features related to the size, shape, and distribution of the roughness patterns were found to influence the adhesion of the bacterial strain on different surfaces. On the laser-structurised surface, the adhesion of Escherichia coli bacteria were reduced by 80% compared to an untreated reference surface.


Assuntos
Antibacterianos , Aderência Bacteriana , Escherichia coli , Lasers , Propriedades de Superfície , Titânio , Titânio/química , Titânio/farmacologia , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Aderência Bacteriana/efeitos dos fármacos , Catálise , Microscopia Eletrônica de Varredura , Humanos , Azul de Metileno/química , Azul de Metileno/farmacologia , Peri-Implantite/microbiologia
7.
Water Sci Technol ; 89(2): 347-356, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39219134

RESUMO

Tire wear microrubber particles (TWMP) are a major source of environmental contamination. Degradation of TWMP is slow and leachates contain toxic constituents including heavy metals, polycyclic aromatic hydrocarbons (PAHs) and organic additives. Few studies have addressed methods to mitigate the potential ecotoxicity of TWMP leachates. This study investigated the effects of UV-C (254 nm) and combined UV-C and vacuum UV (185 nm) treatment (VUV-UV-C) of TWMP leachates on degradation and ecotoxicity. VUV-UV-C treatment mitigated dissolved zinc and degraded the TWMP constituents fluoranthene, pyrene and benzo(a)pyrene by up to 90%, and the additives benzothiazole and phthalates by up to 70%. The potential ecotoxicity and genotoxicity of TWMP constituents were examined before and after UV treatment in bioassays with Escherichia coli, the luminescent bacterium Aliivibrio fischeri, the microalga Raphidocelis subcapitata and the crustacean Daphia magna. VUV-UV-C treatment decreased the potential ecotoxicity up to five-fold as indicated by changes in median effective concentrations (EC50). This was likely due to the formation of less toxic and less bioavailable transformation products. The VUV-UV-C treatment did not require the addition of oxidants or catalysts, and the study indicated a potential of VUV-UV-C as an advanced oxidation process to mitigate toxic compounds in TWMP leachates from urban or industrial sources.


Assuntos
Aliivibrio fischeri , Raios Ultravioleta , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Animais , Aliivibrio fischeri/efeitos dos fármacos , Vácuo , Daphnia/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos
8.
J Med Microbiol ; 73(9)2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39222340

RESUMO

Colistin resistance testing methods such as broth microdilution (BMD) are time-consuming and labour intensive for clinical laboratories. MBT Lipid Xtract Kit on MALDI Biotyper Sirius System (Bruker, Billerica, MA, USA) utilizes lipidomic analysis to identify specific cell wall modifications associated with colistin resistance. We compared MBT to BMD (ComASP Colistin, Liofilchem) across 36 Gram-negative isolates (non-resistant MIC ≤2 µg ml-1, resistant MIC ≥4 µg ml-1). All samples were tested twice on MBT with discrepant results repeated before assessing categorical agreement between MBT and BMD. 44.4% (16/36) of isolates were colistin resistant via BMD. MBT Lipid Xtract had 80.6% agreement (29/36) with BMD, with 5/7 discrepancies corrected to match upon repeat testing. There was 100% agreement for Escherichia coli isolates (n=16). The whole-genome sequencing was completed on the two discrepant Klebsiella pneumoniae isolates, with variants within colistin resistance-associated loci identified (MIC 0.5 µg ml-1: arnC S30T, pmrB T246A, lapB N212T, lpxM S253G, crrB Q287K and MIC >16 µg ml-1: arnC S30T, pmrB R90insRN, pmrB T246A, pmrA E57G, lpxM S253G). Further evaluation, particularly for non-E. coli, of MBT is required prior to implementation in clinical laboratories.


Assuntos
Antibacterianos , Colistina , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana , Colistina/farmacologia , Antibacterianos/farmacologia , Humanos , Bactérias Gram-Negativas/efeitos dos fármacos , Sequenciamento Completo do Genoma , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética
9.
Carbohydr Polym ; 345: 122567, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227104

RESUMO

Solution blowing process was used to prepare cellulose nonwovens, by using N-methyl morpholine-N-oxide (NMMO) as solvent, and salicylic acid (SA) microcapsules as antibacterial additives. The structure and properties of cellulose nonwovens modified with different SA microcapsules contents were compared and evaluated. The results showed that more uniform and denser web structure was formed with the increase of SA microcapsules content, the average fiber diameter of cellulose nonwoven increased from 1.99 µm to 2.65 µm. The air flow resistance and filtration efficiency of cellulose nonwovens increased with addition of SA microcapsules, whereas the mechanical properties, and wearing comfort including air permeability, moisture vapor transfer rate, and softness of cellulose nonwovens decreased slightly, under the same basis weight. SA microcapsules modified cellulose nonwovens exhibited good sustained-release behavior and antimicrobial activity against Escherichia coli. The higher SA microcapsules content in cellulose nonwovens, the faster release rate and the higher antimicrobial activity. The cellulose solution-blown nonwovens modified with SA microcapsules are expected to find applications in medical and healthcare fields due to its antibacterial activity and biodegradability.


Assuntos
Antibacterianos , Cápsulas , Celulose , Escherichia coli , Ácido Salicílico , Solventes , Celulose/química , Ácido Salicílico/química , Ácido Salicílico/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Solventes/química , Liberação Controlada de Fármacos , Óxidos N-Cíclicos/química , Soluções , Testes de Sensibilidade Microbiana
10.
Carbohydr Polym ; 345: 122577, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227109

RESUMO

This study was to investigate the antibacterial effects and metabolites derived from bifidobacterial fermentation of an exopolysaccharide EPS-LM produced by a medicinal fungus Cordyceps sinensis, Cs-HK1. EPS-LM was a partially purified polysaccharide fraction which was mainly composed of Man, Glc and Gal at 7.31:12.95:1.00 mol ratio with a maximum molecular weight of 360 kDa. After fermentation of EPS-LM in two bifidobacterial cultures, B. breve and B. longum, the culture digesta showed significant antibacterial activities, inhibiting the proliferation and biofilm formation of Escherichia coli. Based on untargeted metabolomic profiling of the digesta, the levels of short chain fatty acids, carboxylic acids, benzenoids and their derivatives were all increased significantly (p < 0.01), which probably contributed to the enhanced antibacterial activity by EPS-LM. Since EPS-LM was only slightly consumed for the bifidobacterial growth, it mainly stimulated the biosynthesis of bioactive metabolites in the bifidobacterial cells. The results also suggested that EPS-LM polysaccharide may have a regulatory function on the bifidobacterial metabolism leading to production of antibacterial metabolites, which may be of significance for further exploration.


Assuntos
Antibacterianos , Cordyceps , Escherichia coli , Fermentação , Polissacarídeos Bacterianos , Antibacterianos/farmacologia , Antibacterianos/química , Cordyceps/metabolismo , Cordyceps/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Polissacarídeos Bacterianos/farmacologia , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/metabolismo , Biofilmes/efeitos dos fármacos , Polissacarídeos Fúngicos/farmacologia , Polissacarídeos Fúngicos/química , Testes de Sensibilidade Microbiana
11.
Carbohydr Polym ; 345: 122550, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227117

RESUMO

In the realm of natural polysaccharides, hydrogen bonding is a prevalent feature, yet its role in enhancing photocatalytic antimicrobial properties has been underexplored. In this paper, heterojunctions formed by graphene oxide (GO) and ZIF-8 were locked in sodium alginate/ carboxylated cellulose nanocrystals via hydrogen bonding networks, designated as SCGZ. The SCGZ films exhibit superior photocatalytic performance compared to either ZIF-8 or heterojunctions. This enhancement is primarily due to two key factors: firstly, the hydrogen bonding network significantly enhances the transfer of protons and holes, thereby improving the separation efficiency of photo-generated carriers; secondly, the hydrogen bonding between the layers facilitates a more efficient charge transfer, which expedites the movement of electrons from ZIF-8 to GO upon illumination. In vitro studies demonstrated that the SCGZ films possess remarkable antibacterial capabilities, achieving 99.75 % and 99.61 % inhibition rates against S. aureus and E. coli, respectively. In vivo animal experiments have shown that SCGZ films can significantly accelerate the healing process of damaged tissues, with a healing efficiency of up to 90.5 %. This research provides additional insights into the development of natural polysaccharide-based multi­hydrogen bonded macromolecules with enhanced photocatalytic properties.


Assuntos
Alginatos , Antibacterianos , Celulose , Escherichia coli , Grafite , Nanopartículas , Staphylococcus aureus , Cicatrização , Alginatos/química , Alginatos/farmacologia , Celulose/química , Celulose/farmacologia , Nanopartículas/química , Cicatrização/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Animais , Grafite/química , Grafite/farmacologia , Esterilização/métodos , Ligação de Hidrogênio , Camundongos , Testes de Sensibilidade Microbiana , Catálise
12.
Carbohydr Polym ; 345: 122568, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227122

RESUMO

Bleeding and bacterial infection are common problems associated with wound treatment, while effective blood clotting and vessel regeneration promotion are the primary considerations to design the wound dressing materials. This research presents a chitosan-based hydrogel with grafted quaternary ammonium and polyphosphate (QCSP hydrogel) as the antibacterial hemostatic dressing to achieve burn wound treatment. The tissue adhesion of the hydrogel sealed the blood flow and the polyphosphate grafted to the chitosan promoted the activation of coagulation factor V to enhance the hemostasis. At the same time, the grafted quaternary ammonium enhanced the antibacterial ability of the biodegradable hydrogel wound dressing. In addition, the polydopamine as a photothermal agent was composited into the hydrogel to enhance the antibacterial and reactive oxygen scavenging performance. The in vivo hemostasis experiment proved the polyphosphate enhanced the coagulation property. Moreover, this photothermal property of the composite hydrogel enhanced the burn wound repairing rate combined with the NIR stimulus. As a result, this hydrogel could have potential application in clinic as dressing material for hemostasis and infection prone would repairing.


Assuntos
Antibacterianos , Queimaduras , Quitosana , Hemostasia , Hidrogéis , Indóis , Polímeros , Cicatrização , Quitosana/química , Quitosana/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Queimaduras/tratamento farmacológico , Queimaduras/terapia , Polímeros/química , Polímeros/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Animais , Indóis/química , Indóis/farmacologia , Cicatrização/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Camundongos , Hemostáticos/química , Hemostáticos/farmacologia , Bandagens , Masculino , Ratos , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Ratos Sprague-Dawley , Testes de Sensibilidade Microbiana , Terapia Fototérmica/métodos
13.
Carbohydr Polym ; 345: 122491, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227129

RESUMO

Hydrogels are highly sought-after absorbent materials for absorbent pads; however, it is still challenging to achieve a satisfactory balance between mechanical performance, water absorption capacity, and active functionalities. In this work, we presented double-network hydrogels synthesized through acrylic acid (AA) polymerization in the presence of quaternized cellulose nanofibrils (QCNF) and Fe3+. Spectroscopic and microscopic analyses revealed that the combined QCNF and Fe3+ facilitated the formation of double-network hydrogels with combined chemical and physical crosslinking. The synergistic effect of QCNF and Fe3+ resulted in impressive mechanical properties, including tensile strength of 1.98 MPa, fracture elongation of 838.8 %, toughness of 7.47 MJ m-3, and elastic modulus of 0.35 MPa. In comparison to the single-network PAA hydrogel, the PAA/QCNF/Fe3+ (PQFe) hydrogels showed higher and relatively stable swelling ratios under varying pH levels and saline conditions. The PQFe hydrogels exhibited notable antioxidant activity, as evidenced by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and demonstrated effective antibacterial activity against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). These hydrogels show promising potential as an absorbent interlayer in absorbent pads for active food packaging.


Assuntos
Resinas Acrílicas , Antibacterianos , Celulose , Escherichia coli , Hidrogéis , Ferro , Nanofibras , Staphylococcus aureus , Resistência à Tração , Hidrogéis/química , Hidrogéis/farmacologia , Celulose/química , Staphylococcus aureus/efeitos dos fármacos , Resinas Acrílicas/química , Escherichia coli/efeitos dos fármacos , Nanofibras/química , Ferro/química , Antibacterianos/farmacologia , Antibacterianos/química , Antioxidantes/química , Antioxidantes/farmacologia , Módulo de Elasticidade
14.
Luminescence ; 39(9): e4875, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39228310

RESUMO

The modern nanomedicine incorporates the multimodal treatments into a single formulation, offering innovative cancer therapy options. Nanosheets function as carriers, altering the solubility, biodistribution, and effectiveness of medicinal compounds, resulting in more efficient cancer treatments and reduced side effects. The non-toxic nature of fluorinated graphene oxide (FGO) nanosheets and their potential applications in medication delivery, medical diagnostics, and biomedicine distinguish them from others. Leveraging the unique properties of Lissachatina fulica snail mucus (LfSM), FGO nanosheets were developed to reveal the novel characteristics. Consequently, LfSM was utilized to create non-toxic, environmentally friendly, and long-lasting FGO nanosheets. Ultraviolet-visible (UV-vis) spectroscopy revealed a prominent absorbance peak at 235 nm. The characterization of the synthesized FGO nanosheets involved X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HR-TEM), and atomic force microscopy (AFM) analyses. The antimicrobial activity data demonstrated a broad spectrum of antibacterial effects against Escherichia coli, Bacillus subtilis, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The cytotoxicity efficacy of LfSM-FGO nanosheets against pancreatic cancer cell line (PANC1) showed promising results at low concentrations. The study suggests that FGO nanosheets made from LfSM could serve as alternate factors for in biomedical applications in the future.


Assuntos
Grafite , Nanoestruturas , Caramujos , Grafite/química , Grafite/farmacologia , Animais , Caramujos/química , Humanos , Nanoestruturas/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Testes de Sensibilidade Microbiana , Muco/química , Muco/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Halogenação , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Linhagem Celular Tumoral , Tamanho da Partícula
15.
Luminescence ; 39(9): e4891, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39229976

RESUMO

Lepidagathis cristata (L. cristata) plant produces reducing and capping agents; this study utilized microwave-assisted biogenic synthesis to manufacture silver nanoparticles (AgNPs) using this plant. The structure, morphology, and crystallinity phases of prepared nanoparticles (NPs) were characterized by ultraviolet-visible spectroscopy (UV-viz), powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). Biologically synthesized AgNPs were treated against pathogenic bacteria species including Escherichia coli (E. coli), Bacillus subtilis (B. subtilis), and Staphylococcus aureus (S. aureus) and its highest zone of inhibition 10 ± 1.45 mm, 10 ± 0.74 mm, and 6 ± 0.43 mm, respectively, at the concentration of 100 µg/mL. The cytotoxic activity of AgNPs against MCF-7 breast cancer cells revealed significant growth inhibition by inhibiting cell viability, inhibitory concentration of 50% (IC50) of NPs observed at 55.76 µg/mL concentration. Finally, our findings concluded that the L. cristata-mediated biosynthesized AgNPs proved its potential antibacterial and neoplastic properties against MCF cells by endorsing the inhibition of cell proliferation especially with low concentration.


Assuntos
Antibacterianos , Ensaios de Seleção de Medicamentos Antitumorais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Humanos , Células MCF-7 , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/síntese química , Água/química , Relação Dose-Resposta a Droga , Feminino
16.
Can Vet J ; 65(9): 886-893, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39219609

RESUMO

A 15-month-old spayed female greater Swiss mountain dog was brought to our clinic because of relapsing episodes of urinary tract infection, present since her adoption at 2 mo of age. A diagnosis of chronic bacterial cystitis associated with an invasive, biofilm-forming uropathogenic Escherichia coli was made with bladder-wall histology and fluorescent in situ hybridization analysis. Local treatment with EDTA-tromethamine (EDTA-Tris) infusions along with parenteral cefquinome and prophylactic measures (Type-A proanthocyanidins and probiotics) coincided with clinical and bacterial remission. The dog has been free of clinical signs of urinary tract infection for >4 y. Biofilm-forming uropathogenic E. coli can cause chronic, recurrent cystitis due to low antibiotic efficacy and should be considered in cases of recurrent cystitis in dogs, especially in the absence of identified predisposing factors. This case report describes the diagnostic and therapeutic options that were used to manage a case of this type. Key clinical message: Fluorescent in situ hybridization analysis may be considered in the diagnosis of chronic bacterial cystitis in dogs, and intravesical instillations of EDTA-Tris may be helpful in managing such cases.


Traitement adjuvant intravésical avec de l'EDTA-trométhamine chez un chien présentant une cystite récurrente à Escherichia coli formant des biofilmsUne chienne grand bouvier suisse stérilisée de 15 mois nous a été présentée pour des épisodes d'infection du tractus urinaire récidivants depuis son adoption à l'âge de 2 mois. Une cystite bactérienne chronique associée à un Escherichia coli uropathogène formant des biofilms a été identifiée par l'examen histologique de la paroi vésicale et par hybridation in situ fluorescente. Des instillations intravésicales d'EDTA et trométhamine (EDTA-Tris) en complément d'une antibiothérapie parentérale de courte durée (cefquinome) et de mesures prophylactiques (proanthocyanidines de type A et probiotiques) ont permis une guérison clinique et bactériologique de la cystite pendant plus de 4 ans. Les infections par Escherichia coli formant des biofilms peuvent causer des cystites chroniques récurrentes dues à une faible efficacité des antibiotiques et doivent être incluses dans le diagnostic différentiel des cystites récurrentes chez le chien, particulièrement en l'absence d'autre facteur prédisposant. Ce rapport propose des stratégies diagnostiques et thérapeutiques ayant permis la prise en charge d'un de ces cas.Message clinique clé :L'analyse par hybridation in situ fluorescente peut être envisagé dans le diagnostic de cystite bactérienne chronique chez les chiens, et l'instillation intravésicale d'EDTA-Tris peut être utile dans la gestion de tels cas.(Traduit par les auteurs).


Assuntos
Antibacterianos , Biofilmes , Cistite , Doenças do Cão , Ácido Edético , Infecções por Escherichia coli , Cães , Animais , Doenças do Cão/tratamento farmacológico , Doenças do Cão/microbiologia , Feminino , Cistite/veterinária , Cistite/tratamento farmacológico , Cistite/microbiologia , Ácido Edético/uso terapêutico , Ácido Edético/administração & dosagem , Biofilmes/efeitos dos fármacos , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/tratamento farmacológico , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Administração Intravesical , Escherichia coli/efeitos dos fármacos , Recidiva
17.
Sci Rep ; 14(1): 20336, 2024 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223136

RESUMO

Antimicrobial potential of bioactive glass (BAG) makes it promising for implant applications, specifically overcoming the toxicity concerns associated with traditional antibacterial nanoparticles. The 58S composition of BAG (with high Ca and absence of Na) has been known to exhibit excellent bioactivity and antibacterial behaviour, but the mechanisms behind have not been investigated in detail. In this pioneering study, we are using Atomic Force Microscopy (AFM) to gain insights into 58S BAG's adhesive interactions with planktonic cells of both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria; along with the impact of crystallinity on antibacterial properties. We have recorded greater bacterial inhibition by amorphous BAG compared to semi-crystalline glass-ceramics and stronger effect against gram-negative bacteria via conventional long-term antibacterial tests. AFM force distance curves has illustrated substantial bonding between bacteria and BAG within the initial one second (observed at a gap of 250 ms) of contact, with multiple binding events. Further, stronger adhesion of BAG with E.coli (~ 6 nN) compared to S. aureus (~ 3 nN) has been found which can be attributed to more adhesive nano-domains (size effect) distributed uniformly on E.coli surface. This study has revealed direct evidence of impact of contact time and 58S BAG's crystalline phase on bacterial adhesion and antimicrobial behaviour. Current study has successfully demonstrated the mode and mechanisms of initial bacterial adhesion with 58S BAG. The outcome can pave the way towards improving the designing of implant surfaces for a range of biomedical applications.


Assuntos
Antibacterianos , Aderência Bacteriana , Cerâmica , Escherichia coli , Vidro , Microscopia de Força Atômica , Staphylococcus aureus , Microscopia de Força Atômica/métodos , Cerâmica/química , Aderência Bacteriana/efeitos dos fármacos , Vidro/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química
18.
J Biomed Mater Res B Appl Biomater ; 112(9): e35480, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39223717

RESUMO

The aim of this study was to develop multifunctional magnetic poly(ε-caprolactone) (PCL) mats with antibacterial properties for bone tissue engineering and osteosarcoma prevention. To provide good dispersion of magnetic iron oxide nanoparticles (IONs), they were first grafted with PCL using a novel three-step approach. Then, a series of PCL-based mats containing a fixed amount of ION@PCL particles and an increasing content of ascorbic acid (AA) was prepared by electrospinning. AA is known for increasing osteoblast activity and suppressing osteosarcoma cells. Composites were characterized in terms of morphology, mechanical properties, hydrolytic stability, antibacterial performance, and biocompatibility. AA affected both the fiber diameter and the mechanical properties of the nanocomposites. All produced mats were nontoxic to rat bone marrow-derived mesenchymal cells; however, a composite with 5 wt.% of AA suppressed the initial proliferation of SAOS-2 osteoblast-like cells. Moreover, AA improved antibacterial properties against Staphylococcus aureus and Escherichia coli compared to PCL. Overall, these magnetic composites, reported for the very first time, can be used as scaffolds for both tissue regeneration and osteosarcoma prevention.


Assuntos
Ácido Ascórbico , Poliésteres , Staphylococcus aureus , Engenharia Tecidual , Poliésteres/química , Ácido Ascórbico/química , Ácido Ascórbico/farmacologia , Humanos , Ratos , Animais , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Nanopartículas de Magnetita/química , Osteoblastos/metabolismo , Osteoblastos/citologia , Linhagem Celular Tumoral , Osteossarcoma/patologia , Osso e Ossos , Nanocompostos/química , Alicerces Teciduais/química , Teste de Materiais
19.
Afr J Reprod Health ; 28(8): 133-139, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39225579

RESUMO

Diapers, being one of the most used items for infant care, it is imperative that they are always free of contamination from microorganisms. The objective of this study is to determine the rate of bacterial contamination and the antibiotics profile of isolated bacteria from unused diapers sold in markets in Enugu Metropolis, southeast Nigeria. The study also investigated the effectiveness of the Nigerian Consumer protection laws towards maintaining the standard of care for infants and toddlers. Fifty pieces of different brands of diapers were sampled for bacterial contamination using standard bacteriological procedures. The results show that out of 50 samples analyzed, bacterial growths were identified in 9 (18%), of which five different bacterial species were isolated. The most prevalent being Escherichia coli and Staphylococcus aureus 3 (33.3%). Other bacteria isolated were Lactobacillus spp, Klebsiella spp, and Streptococcus spp 1 (11.1%). There was no statistically significant difference in the distribution of the bacterial contamination of diapers across the different brands(p>0.05). We conclude that baby diapers sold in markets in Enugu metropolis are prone to contamination with bacteria.We recommend that appropriate measures should be taken during the manufacturing process to reduce or prevent the incidence of bacterial contamination of diapers.


Les couches étant l'un des articles les plus utilisés pour les soins des nourrissons, il est impératif qu'elles soient toujours exemptes de contamination par des micro-organismes. L'objectif de cette étude est de déterminer le taux de contamination bactérienne et le profil antibiotique des bactéries isolées provenant de couches inutilisées vendues sur les marchés de la métropole d'Enugu, dans le sud-est du Nigeria. L'étude a également examiné l'efficacité des lois nigérianes sur la protection des consommateurs pour maintenir le niveau de soins pour les nourrissons et les jeunes enfants. Cinquante morceaux de couches de différentes marques ont été échantillonnés pour détecter toute contamination bactérienne en utilisant des procédures bactériologiques standard. Les résultats montrent que sur 50 échantillons analysés, des croissances bactériennes ont été identifiées dans 9 (18 %), parmi lesquels cinq espèces bactériennes différentes ont été isolées. Les plus répandus sont Escherichia coli et Staphylococcus aureus 3 (33,3 %). Les autres bactéries isolées étaient Lactobacillus spp, Klebsiella spp et Streptococcus spp 1 (11,1 %). Il n'y avait pas de différence statistiquement significative dans la répartition de la contamination bactérienne des couches entre les différentes marques (p>0,05). Nous concluons que les couches pour bébés vendues sur les marchés de la métropole d'Enugu sont sujettes à la contamination bactérienne. Nous recommandons que des mesures appropriées soient prises pendant le processus de fabrication pour réduire ou prévenir l'incidence de la contamination bactérienne des couches.


Assuntos
Antibacterianos , Escherichia coli , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Humanos , Nigéria , Antibacterianos/farmacologia , Lactente , Escherichia coli/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/efeitos dos fármacos , Klebsiella/isolamento & purificação , Klebsiella/efeitos dos fármacos , Lactobacillus/isolamento & purificação , Streptococcus/isolamento & purificação , Streptococcus/efeitos dos fármacos
20.
BMC Microbiol ; 24(1): 360, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39306662

RESUMO

BACKGROUND: Urinary tract infections (UTIs) are the second most common infection, affecting 150 million people each year worldwide. Enterobacteriaceae species expressing extended-spectrum ß-lactamases (ESBLs) are on the rise across the globe and are becoming a severe problem in the therapeutic management of clinical cases of urinary tract infection. Knowledge of the prevalence and antibiogram profile of such isolates is essential to develop an appropriate treatment methodology. This study aimed to investigate the prevalence of Enterobacteriaceae isolates exhibiting ESBL and their selective oral antibiogram profile at the district general hospital, Polonnaruwa. RESULTS: A total of 4386 urine specimens received to the Microbiology Laboratory during the study period. Among them, 1081 (24.6%) showed positive results for urine culture while 200/1081 specimens showed ESBL isolates. Out of the selected 200 specimen's majority (67.5%) of samples received from the In-Patient Department. There were 200 patients and reported that 115 (57.5%) were females and 85 (42.5%) were males. The majority (51%) of the patients belong to the age group of 55-74 years. Among the ESBLs positive specimens, the majority 74.5% (n = 149) identified organisms were E. coli followed by Klebsiella spp.17.5% (n = 35), Enterobacteriaceae 7% (n = 14) and only1% (n = 2) isolate of Proteus spp. Mecillinam (87.92%) and Nitrofurantoin (83.2%) showed higher effectiveness against E. coli. Nitrofurantoin showed the highest effectiveness against Klebsiella spp. (40%), other Enterobacteriaceae spp. (100%). Proteus spp. showed 100% effectiveness and resistance respectively against Ciprofloxacin, Cotrimoxazole and Nitrofurantoin. CONCLUSION: The most predominant ESBLs producing uro-pathogen was the E. coli in the study setting and E. coli had higher sensitivity rate against Mecillinam. Among currently used oral antibiotics Nitrofurantoin was the best choice for UTIs caused by ESBL producers.


Assuntos
Antibacterianos , Infecções por Enterobacteriaceae , Enterobacteriaceae , Testes de Sensibilidade Microbiana , Infecções Urinárias , beta-Lactamases , Humanos , Infecções Urinárias/microbiologia , Infecções Urinárias/tratamento farmacológico , Feminino , Pessoa de Meia-Idade , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Masculino , beta-Lactamases/metabolismo , Idoso , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/tratamento farmacológico , Adulto , Adulto Jovem , Idoso de 80 Anos ou mais , Adolescente , Nitrofurantoína/farmacologia , Nitrofurantoína/uso terapêutico , Prevalência , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli/enzimologia
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