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European Journal of Microbiology and Immunology
Authors:
Péter Pallós
,
Márió Gajdács
,
Edit Urbán
,
Yvett Szabados
,
Klaudia Szalai
,
Lívia Hevesi
,
Anna Horváth
,
Anna Kuklis
,
Devina Morjaria
,
Wajiha Iffat
,
Helal F. Hetta
,
Nicola Piredda
, and
Matthew Gavino Donadu

Abstract

The clinical role of Acinetobacter baumannii has been highlighted in numerous infectious syndromes with a high mortality rate, due to the high prevalence of multidrug-resistant (MDR) isolates. The treatment and eradication of this pathogen is hindered by biofilm-formation, providing protection from noxious environmental factors and antimicrobials. The aim of this study was to assess the antibiotic susceptibility, antiseptic susceptibility and biofilm-forming capacity using phenotypic methods in environmental A. baumannii isolates. One hundred and fourteen (n = 114) isolates were collected, originating from various environmental sources and geographical regions. Antimicrobial susceptibility testing was carried out using the disk diffusion method, while antiseptic susceptibility was performed using the agar dilution method. Determination of biofilm-forming capacity was carried out using a microtiter-plate based method. Resistance in environmental A. baumannii isolates were highest for ciprofloxacin (64.03%, n = 73), levofloxacin (62.18%, n = 71) and trimethoprim-sulfamethoxazole (61.40%, n = 70), while lowest for colistin (1.75%, n = 2). Efflux pump overexpression was seen in 48.25% of isolates (n = 55), 49.12% (n = 56) were classified as MDR. 6.14% (n = 7), 9.65% (n = 11), 24.65% (n = 28) and 59.65% (n = 68) of isolates were non-biofilm producers, weak, medium, and strong biofilm producers, respectively. No significant differences were observed between non-MDR vs. MDR isolates regarding their distribution of biofilm-producers (P = 0.655). The MIC ranges for the tested antiseptics were as follows: benzalkonium chloride 16–128 μg mL−1, chlorhexidine digluconate 4–128 μg mL−1, formaldehyde 64–256 μg mL−1 and triclosan 2–16 μg mL−1, respectively. The conscientious use of antiseptics, together with periodic surveillance, is essential to curb the spread of these bacteria, and to maintain current infection prevention capabilities.

Open access
Acta Alimentaria
Authors:
V. László
,
D. Szakos
,
V. Csizmadiáné Czuppon
, and
Gy. Kasza

Abstract

Consumer trust is essential to any market but particularly relevant to the food sector. Sustainable food systems require integration of small-scale food producers, for them consumer trust is pivotal. However, comprehensive measurement of consumer trust regarding local food is a less explored area. Based on the adjusted version of Benson's trust toolkit, local food trust was measured on four levels. This approach, connecting locality/proximity to food-related trust, was tested with a representative quantitative consumer survey (n = 1,001) in Hungary. Interpersonal trust, general organisation trust, local food chain trust, and local food product trust were measured on a 5-point Likert scale. Correlation and boxplot analysis conducted revealed that trust levels correlate significantly but remain independent from demographic characteristics, indicating that trust in local food is not region-, education-, or income-specific amongst Hungarian consumers. A relatively high level of consumer trust was measured for local food products and producers compared to other stakeholders, strengthening the assumption for the proximity-trust relationship regarding food. This is a key factor for small-scale food producers: only shared values with the local community and earned trust can attract customers despite less flexibility with pricing and limited capacity for advertising.

Open access

Abstract

Extensive use of carbapenems may lead to selection pressure for Stenotrophomonas maltophilia (SM) in hospital environments. The aim of our study was to assess the possible association between systemic antibiotic use and the incidence of SM. A retrospective, observational study was carried out in a tertiary-care hospital in Hungary, between January 1st 2010 and December 31st 2019. Incidence-density for SM and SM resistant to trimethoprim-sulfamethoxazole (SXT) was standardized for 1000 patient-days, while systemic antibiotic use was expressed as defined daily doses (DDDs) per 100 patient-days. Mean incidence density for SM infections was 0.42/1000 patient-days; 11.08% were were resistant to SXT, the mean incidence density for SXT-resistant SM was 0.047/1000 patient-days. Consumption rate for colistin, glycopeptides and carbapenems increased by 258.82, 278.94 and 372.72% from 2010 to 2019, respectively. Strong and significant positive correlations were observed with the consumption of carbapenems (r: 0.8759; P < 0.001 and r: 0.8968; P < 0.001), SXT (r: 0.7552; P = 0.011 and r: 0.7004; P = 0.024), and glycopeptides (r: 0.7542; P = 0.012 and r: 0.8138; P < 0.001) with SM and SXT-resistant SM incidence-density/1000 patient-days, respectively. Implementation of institutional carbapenem-sparing strategies are critical in preserving these life-saving drugs, and may affect the microbial spectrum of infections in clinical settings.

Open access

Abstract

Prosthetic joint infections (PJIs) are dreaded arthroplasty complications often caused by Staphylococcus aureus. Due to methicillin-resistant S. aureus (MRSA) strains or biofilm formation, successful treatment remains difficult. Currently, two-stage revision surgery constitutes the gold standard therapy of PJIs, sometimes replaced or supplemented by debridement, antibiotics, and implant retention (DAIR). Given the dire consequences of therapeutic failure, bacteriophage therapy might be another treatment option. Here we provide a comprehensive literature review addressing the efficacy of phages applied against S. aureus as causative agent of PJIs. The included 17 publications had in common that the applied phages proved to be effective against various S. aureus isolates including MRSA even in biofilms. Experiments with mice, rats, rabbits, and moth larvae confirmed favorable features of phage preparations in PJI treatment in vivo; including its synergistic with antibiotics. Case reports of PJI patients unanimously described the bacterial eradication following, alongside other measures, intravenous and intra-articular phage administration. Generally, no major side effects occurred, but in some cases elevated liver transaminases were observed. To conclude, our review compiled promising evidence suggesting the safety and suitability of phage therapy as an adjuvant to DAIR in S. aureus PJIs, and thus, underscores the significance of further research.

Open access
European Journal of Microbiology and Immunology
Authors:
Kantima Choosang
,
Siriphan Boonsilp
,
Kanyanan Kritsiriwuthinan
,
Palin Chumchuang
,
Nanthawan Thanacharoensakun
,
Aminoh Saai
, and
Sawanya Pongparit

Abstract

Plasmodium vivax is the most prevalent cause of malaria in Thailand and is predominant in malarial endemic areas worldwide. P. vivax infection is characterized by low parasitemia, latent liver-stage parasites, or asymptomatic infections leading to underreported P. vivax cases. These are significant challenges for controlling and eliminating P. vivax from endemic countries. This study developed and evaluated a dot-blot enzyme-linked immunosorbent assay (ELISA) using PvMSP1-42 recombinant antigen for serological diagnosis based on the detection of antibodies against P. vivax. The optimal PvMSP1-42 concentration and dilutions of anti-human IgG horseradish peroxidase (HRP)-conjugated antiserum were tested on 88 serum samples from P. vivax, Plasmodium falciparum and bacterial infection, including healthy individuals. A cut-off titer of 1:800 produced optimal values for sensitivity and specificity of 90.9 and 98.2%, respectively, with an accuracy of 95.5%. The positive and negative predictive values were 96.8 and 94.7% respectively. The results from microscopic examination and dot-blot ELISA showed strong agreement with the 0.902 kappa index. Thus, the dot-blot ELISA using PvMSP1-42 antigen provided high sensitivity and specificity suitable for serodiagnosis of P. vivax infection. The test is a simple and quick diagnostic assay suitable for field testing as it does not require specific equipment or particular skills.

Open access

Abstract

This study investigates the potential of utilising oleosomes extracted from hazelnuts in the formulation of liquid margarines. Aqueous extraction methods were employed to isolate oleosomes from hazelnuts, revealing approximately 83.07% fat and 2.48% protein content in hazelnut oleosomes. The stability of oleosomes at various pH levels (3–10) was examined, showing stability at pH 7 but instability at extreme pH values. Evaluation at pH 7 indicated small particle size (D3,2 ≈ 3.58 μm) and a ζ-potential of approximately −33.8 mV for isolated oleosomes. Subsequently, double emulsions were formulated by substituting traditional oil with varying oleosome concentrations (0–30%) in liquid margarine. Rheological and oxidative analyses of these margarines demonstrated decreased elastic and viscous moduli, hardness, and spreadability, alongside enhanced oxidative stability with increasing oleosome concentration. These findings suggest hazelnut-derived oleosomes offer significant stability advantages over conventional liquid margarine, presenting a promising avenue for functionally enhanced food products in the food industry.

Open access
European Journal of Microbiology and Immunology
Authors:
Verner N. Orish
,
Sylvester Y. Lokpo
,
Precious K. Kwadzokpui
,
Rufai Safianu
,
Aleksandra Marinkovic
,
Stephanie Prakash
,
Chuku Okorie
,
Ricardo Izurieta
,
Rajashree Pandit
, and
Adekunle Sanyaolu

Abstract

Background

Although, several studies have reported abnormal Mean Corpuscular Volume (MCV) values and anaemia associated with malaria infections with a focus on Plasmodium falciparum among patients with complicated and uncomplicated malaria, none has looked at the association with asymptomatic malaria. This study aimed to assess this association.

Methods

We conducted a cross-sectional study using 3 mL of blood samples from 549 children aged 5–17 years attending 5 schools selected in the Volta Region. Semi-structured questionnaires were administered to the children to obtain demographic data. Blood samples were collected to estimate the children's full blood count (FBC) and malaria status. Data obtained were analysed using STATA 15 software. P-values of less than 0.05 were considered statistically significant.

Results

Most of the children in this study (49.9%) had normal MCV (81.3–91.3 fL) with an overall malaria prevalence of 55.6 % (95% CI: 51.3–59.8) and anaemia prevalence of 48.6% (95% CI 44.4–52.9). Most anaemic children had normal MCV (81.3–91.3 fL) (49.8, 95% CI 43.7–56.0). The predicted probability of malaria was highly likely among children with normal MCV (81.3–91.3 fL) but with high variability and uncertainty among those with low MCV (<81.3 fL) and high MCV (>91.3 fL).

Conclusion

This study shows a reduced predicted probability of malaria among children with low and high MCV, playing a protective function against malaria. Further studies are required to elucidate the interaction.

Open access

Abstract

Identification of cytotoxic T lymphocyte (CTL) epitopes from tumor related antigens is a promising approach for malignant tumor immunotherapy. TC2N, a recently identified tumor associated antigen from human glioblastoma, is regarded as a promising target of tumor-specific immunotherapy. As one of the most widely used histocompatibility molecules in Chinese is HLA-A*0201, we were able to identify the TC2N peptides that are provided by this molecular type. A panel of antigenic peptides produced from TC2N were predicted by using a computer tool. The binding affinities of three peptides with the highest predicted score to the HLA-A*0201 molecule were evaluated after synthesis. In vitro and in vivo stimulation of the main T-cell response against the predicted peptides. The results demonstrated that TC2N (152-160) was able to release IFN-γ and lyse U251 cells in vitro as well as in vivo by eliciting peptide-specific CTLs. Our results indicated that peptide TC2N (152-160) (RLYGSVCDL) was a novel HLA-A2.1-restricted CTL epitope capable of inducing TC2N specific CTLs in vitro. As TC2N might qualify as a viable target for immunotherapeutic approaches for patients with GBM, we speculated that the newly identified epitope RLYGSVCDL would be of potential use in peptide-based, cancer-specific immunotherapy against GBM.

Open access

Abstract

Autophagy is a cellular stress-induced intracellular process, through which damaged cellular components are decomposed via lysosomal degradation. This process plays important roles in host innate immunity, particularly the elimination of intracellular pathogens inside host macrophages. A more detailed understanding of the roles of autophagic events in the effective manifestation of macrophagic antimycobacterial activity is needed. Furthermore, the effects of medicinal plants on macrophagic autophagy response to mycobacterial infection need to be clarified. We herein examined the significance of autophagic events in the manifestation of host immunity during mycobacterial infection, by performing a literature search using PubMed. Recent studies demonstrated that autophagy up-regulated macrophage functions related to the intracellular killing of mycobacteria, even when pathogens were residing within the cytoplasm of macrophages. The majority of medicinal plants potentiated macrophagic autophagy, thereby enhancing their antimycobacterial functions. In contrast, most medicinal plants down-regulate the development and activation of the Th17 cell population, which reduces macrophage antimycobacterial activity. These opposing effects of medicinal plants on macrophage autophagy (enhancement) and Th17 cell functions (inhibition) may provide a plausible explanation for the clinical observation of their modest efficacy in the treatment of mycobacterial infections.

Open access

Abstract

Dietary iron intake causes the elevation of ferritin levels, and higher iron intake might improve insulin resistance and cardiovascular diseases. The aim of this study was to determine the relationship between dietary iron intake and serum ferritin levels, insulin resistance, and nutritional status in patients with cardiovascular disease. Health information of individuals were obtained with a questionnaire form. There were a total of 103 patients, 59 male (57.3%) and 44 female (42.7%). Patients also filled a questionnaire on dietary habits, a 3-day food record. There was a statistically significant difference between ferritin quartiles and total cholesterol, HDL-C, non-HDL-C, LDL-C/HDL-C ratio, and TG/HDL-C ratio (P < 0.05). Study data show that dietary iron intake was associated with the elevation of serum ferritin levels (P < 0.05) and this difference was significant in Q1 and Q4 groups in post-hoc analysis. There was a negative correlation between serum ferritin levels and total cholesterol and HDL-C in patients with insulin resistance (r = −0.384, P < 0.05; r = −0.520, P < 0.05). In conclusion we found a strong association between serum ferritin levels and inflammation, causing an oxidative stress, atherosclerosis, and bringing along cardiometabolic diseases such as cardiovascular diseases and type 2 DM.

Open access