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1.
Foodborne Pathog Dis ; 21(4): 268-274, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38265446

RESUMO

Cronobacter sakazakii is an important foodborne pathogen in powder infant formula (PIF). The objective of this study was to evaluate the inactivation effect of Rosa roxburghii Tratt pomace crude extract (RRPCE) on C. sakazakii isolated from PIF and to reveal the mechanism of action. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were used to evaluate the inhibitory activity of RRPCE against C. sakazakii. The inhibitory mechanism was revealed from the perspective of effects of RRPCE on intracellular adenosine 5'-triphosphate (ATP), reactive oxygen species (ROS), membrane potential, protein and nucleic acid leakage, and cell morphology of C. sakazakii. The inactivation effects of RRPCE on C. sakazakii in biofilms on stainless steel, tinplate, glass, silica gel, polyethylene terephthalate, and polystyrene to evaluate its potential as a natural disinfectant. The results showed that the MIC and MBC of RRPCE against C. sakazakii were 7.5 and 15 mg/mL, respectively. After treatments with RRPCE, intracellular ATP content decreased significantly while intracellular ROS level increased significantly (p < 0.05). The cell membrane depolarization, large leakage of proteins and nucleic acids, and severely damaged cell morphology also occurred in C. sakazakii treated with RRPCE. In addition, a 20-minute treatment with 2 MIC (15 mg/mL) of RRPCE could inactivate all C. sakazakii (from 6.10 to 6.40 CFU/mL) in biofilms on all six contact surfaces. Our findings suggest that RRPCE is ideal for the inactivation of C. sakazakii and has the potential to be used as a natural disinfectant for the inactivation of PIF packaging materials and containers.


Assuntos
Cronobacter sakazakii , Cronobacter , Desinfetantes , Rosa , Humanos , Lactente , Fórmulas Infantis , Espécies Reativas de Oxigênio/farmacologia , Trifosfato de Adenosina , Desinfetantes/farmacologia , Microbiologia de Alimentos
2.
Foodborne Pathog Dis ; 21(3): 160-167, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38079263

RESUMO

The purpose of this study was to reveal the antibacterial activity and mechanism of Polygonatum sibiricum extract (PSE) against Bacillus cereus and further analyze the application of PSE in pasteurized milk (PM). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values and growth curve analysis were used to evaluate the antibacterial activity of PSE against B. cereus. The changes in contents of intracellular adenosine 5'-triphosphate (ATP) and reactive oxygen species (ROS), activities of ß-galactosidase, adenosine triphosphatase (ATPase) and alkaline phosphatase (AKP), cell membrane potential, protein and nucleic acid leakage, and cell morphology were used to reveal the antibacterial mechanism. The effects of PSE on viable count and sensory evaluation of PM during storage were analyzed. The results showed that the MIC and MBC values of PSE against B. cereus were 2 and 4 mg/mL, respectively. Growth curve analysis showed that PSE with a concentration of 2 MIC could completely inhibit the growth of B. cereus. After treatments with PSE, the levels of intracellular ATP and ROS, and activities of ß-galactosidase, ATPase and AKP of B. cereus were significantly reduced (p < 0.05). Cell membrane was depolarized, amounts of protein and nucleic acid leakage were significantly increased (p < 0.05), and cell morphology was destroyed. Furthermore, PSE significantly reduced the viable count of B. cereus in PM and improved the sensory quality of PM during storage (p < 0.05). Together, our findings suggested that PSE had the desired effect as a natural preservative applied in PM.


Assuntos
Ácidos Nucleicos , Polygonatum , Animais , Leite/microbiologia , Bacillus cereus , Espécies Reativas de Oxigênio/farmacologia , Antibacterianos/farmacologia , beta-Galactosidase/farmacologia , Extratos Vegetais/farmacologia , Adenosina Trifosfatases/farmacologia , Trifosfato de Adenosina
3.
Clin Neurol Neurosurg ; 241: 108278, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38631155

RESUMO

OBJECTIVES: We aimed to determine whether asymptomatic carotid artery stenosis (ACS) induced cognitive impairments were related to the cholinergic hyperintensity pathway. METHODS: This cross-sectional study included patients with moderate-to-severe ACS, who were categorized into mild cognitive impairment (MCI) and normal cognition groups on the basis of Montreal Cognitive Assessment (MoCA) scores. The cholinergic pathway hyperintensity scale (CHIPS), Fazekas, and medial temporal atrophy (MTA) scores were assessed. SPSS software was used for statistical analyses. RESULTS: A total of 117 ACS patients (70.89 ± 8.81 years) and 105 controls (67.87 ± 9.49 years) were evaluated (t = 2.46, p = 0.015). The ACS group showed a worse median Mini-Mental Status Examination (MMSE) score (z = -2.41, p = 0.016) and MoCA score (z = -3.51, p < 0.001), and a significantly higher median total CHIPS score (z = 4.88, p < 0.001) and mean Fazekas score (t = 2.39, p = 0.018). In the correlation analysis, the MoCA score showed a significant negative correlation with the CHIPS score (ρ = -0.41, p < 0.001) and Fazekas score (ρ = -0.31, p < 0.001) in ACS group. Logistic regression analyses suggested that CHIPS scores were risk factors for MCI in patients with ACS (odds ratio [OR] = 1.07, 95% Confidence Interval [CI]1.01-1.13 and controls (OR = 1.09, 95%CI 1.01-1.17), while the MTA and Fazekas scores showed no predictive power. The receiver operating characteristic curve showed that the area under the curve of the CHIPS score for predicting MCI was 0.71 in ACS group, but was only 0.57 in controls. CONCLUSIONS: Patients with ACS showed poorer cognitive performance and higher CHIPS and Fazekas scores. CHIPS, but not Fazekas, scores were risk factors for cognitive impairment and were a valuable factor to predict MCI in patients with ACS.


Assuntos
Estenose das Carótidas , Disfunção Cognitiva , Humanos , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Masculino , Feminino , Idoso , Disfunção Cognitiva/etiologia , Pessoa de Meia-Idade , Estudos Transversais , Imageamento por Ressonância Magnética , Testes de Estado Mental e Demência , Cognição/fisiologia , Testes Neuropsicológicos , Idoso de 80 Anos ou mais
4.
Materials (Basel) ; 11(12)2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30567350

RESUMO

In this study, a static tensile test of secondary co-cure reinforcement (SCR) of laminates revealed the damage and fracture locations in the respective structure. Test results indicated that adhesive debonding was the primary cause of structural failure. Finite element modeling (FEM) performed on the large opening laminate and strengthening structure consisted of simulations of the axial tension experiment, damage assessment, and the final load estimate. It was observed that the tensile strength of SCR was increased by 10.81% in comparison with the unrepaired structure. The results of FEM indicated that the initiation and propagation of damage, and final failure, were located in the layer of reinforcing section which was bonded to the adhesive layer, proving that the performance of the adhesive layer was the dominating factor with regard to the reinforced structure and that the thickness of the reinforcing section could be reduced to lessen the weight.

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