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1.
EJNMMI Rep ; 8(1): 8, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748324

RESUMEN

BACKGROUND: To evaluate the efficacy of PET/CT using18F-FDG (18F-fluorodeoxyglucose) as a radiotracer compared to conventional bone marrow biopsy (BMB) in detecting infiltration to bone marrow (BM) in pediatric patients with lymphoma at the time of initial diagnosis. METHODS: 66 pediatric patients with lymphoma (47Hodgkin's and 19non-Hodgkin's lymphoma) were referred for initial staging by18F-FDG PET/CT study. All patients underwent bilateral iliac BMB and 18F-FDG PET/CT scan with no more than 2 weeks interval in-between. Follow-up for at least 6 months was used as a reference standard to compare diagnostic performance between two modalities in detecting bone marrow infiltration (BMI). RESULTS: Sensitivity, specificity, accuracy, as well as positive and negative predictive values of 18F-FDG PET/CT in detecting BMI were (80%, 86%, 85%, 63%, and 94%) in contrast to BMB (80%, 53%, 59%, 33%, and 90%) respectively. 18F-FDG PET/CT was concordant to BMB in 39/66 patients (59%). CONCLUSION: 18F-FDG PET/CT was more accurate and specific, with higher predictive values than BMB in detecting BMI during initial staging of pediatric lymphoma. In most pediatric lymphoma patients, 18F-FDG PET/CT can be used instead of BMB to determine BMI during their initial staging process.

2.
Ecotoxicol Environ Saf ; 263: 115258, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37478569

RESUMEN

The presence of high salinity levels in textile wastewater poses a significant obstacle to the process of decolorizing azo dyes. The present study involved the construction of a yeast consortium HYC, which is halotolerant and was recently isolated from wood-feeding termites. The consortium HYC was mainly comprised of Sterigmatomyces halophilus SSA-1575 and Meyerozyma guilliermondii SSA-1547. The developed consortium demonstrated a decolourization efficiency of 96.1% when exposed to a concentration of 50 mg/l of Reactive Black 5 (RB5). The HYC consortium significantly decolorized RB5 up to concentrations of 400 mg/l and in the presence of NaCl up to 50 g/l. The effects of physicochemical factors and the degradation pathway were systematically investigated. The optimal pH, salinity, temperature, and initial dye concentration were 7.0, 3%, 35 °C and 50 mg/l, respectively. The co-carbon source was found to be essential, and the addition of glucose resulted in a 93% decolorization of 50 mg/l RB5. The enzymatic activity of various oxido-reductases was assessed, revealing that NADH-DCIP reductase and azo reductase exhibited greater activity in comparison to other enzymes. UV-Visible (UV-vis) spectrophotometry, Fourier-transform infrared spectroscopy (FTIR), high-performance liquid chromatography (HPLC), and gas chromatography-mass spectrometry (GC-MS) were utilized to identify the metabolites generated during the degradation of RB5. Subsequently, a metabolic pathway was proposed. The confirmation of degradation was established through alterations in the functional groups and modifications in molecular weight. The findings indicate that this halotolerant yeast consortium exhibits promising potential of degrading dye compounds. The results of this study offer significant theoretical basis and crucial perspectives for the implementation of halotolerant yeast consortia in the bioremediation of textile and hypersaline wastewater. This approach is particularly noteworthy as it does not produce aromatic amines.


Asunto(s)
Compuestos Azo , Aguas Residuales , Compuestos Azo/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Cromatografía Líquida de Alta Presión , Biodegradación Ambiental , Colorantes/química
3.
Cureus ; 15(6): e40843, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37489201

RESUMEN

The objective of this study was to evaluate the impact of vitamin D supplementation on hemoglobin levels (Hb) in patients with chronic kidney disease (CKD) undergoing hemodialysis. A systematic search was conducted in electronic databases (PubMed/Medline, Cochrane Library, and Google Scholar) from inception to April 21, 2023. Inclusion criteria were applied to select relevant studies. Statistical analyses were performed using Review Manager 5.4.1. A random-effects model was used to address heterogeneity, and the mean difference (MD) with the corresponding 95% confidence interval (CI) was reported. Ten studies were included in the analysis, comprising seven clinical trials, two randomized clinical trials, and one retrospective observational study. Subgroup analysis was conducted based on the duration of follow-up: 12 weeks, three months, six months, 12 months, 15 months, and 18 months. A significant increase in hemoglobin levels was observed after 12 months (MD = -0.98 [95% CI -1.88, -0.08]; p = 0.03; I2 = 91%) and 18 months (MD = -1.80 [95% CI -2.56, -1.04]; p < 0.00001; I2 = Not applicable). However, there was no statistically significant relationship between vitamin D supplementation and hemoglobin levels at 12 weeks, three months, six months, and 15 months. The pooled analysis demonstrated a significant increase in hemoglobin levels with vitamin D supplementation (MD = -0.61 [95% CI -0.96, -0.26]; p = 0.03; I2 = 60.7%). This analysis highlights the significant role of vitamin D supplementation in improving anemia in patients with CKD undergoing hemodialysis. Vitamin D supplementation was found to significantly increase hemoglobin levels, particularly after 12 months and 18 months of supplementation.

4.
Int J Biol Macromol ; 246: 125594, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37390994

RESUMEN

This study involved the extraction of an exopolysaccharide (EPS) from Azotobacter salinestris AZ-6, which was isolated from soil cultivated with leguminous plants. In a medium devoid of nitrogen, the AZ-6 strain displayed a maximum EPS yield of 1.1 g/l and the highest relative viscosity value of 3.4. The homogeneity of the polymer was demonstrated by the average molecular weight of 1.61 × 106 Da and a retention time of 17.211 min for levan. The presence of characteristic functional groups and structural units of carbohydrate polymers has been confirmed through spectroscopic analyses utilizing Fourier-transform infrared (FT-IR) and nuclear magnetic resonance (NMR) techniques. Thermogravimetric analysis (TGA) revealed a noteworthy decrease in weight (74 %) in the temperature range spanning from 260 to 350 °C. X-ray diffraction (XRD) was utilized to verify the crystalline and amorphous characteristics of EPS-AZ-6. The EPS-AZ-6 exhibited significant cytotoxicity against the MCF-7 tumor cell line, as evidenced by an IC50 value of 6.39 ± 0.05 µg/ml. It also demonstrated a moderate degree of cytotoxicity towards HepG-2 cell line, as indicated by an IC50 value of 29.79 ± 0.41 µg/ml. EPS-AZ-6 exhibited potent antioxidant and in vitro antibacterial properties. These characteristics suggest the potential application value of EPS-AZ-6 in the food industry and pharmaceutical applications.


Asunto(s)
Azotobacter , Espectroscopía Infrarroja por Transformada de Fourier , Antioxidantes/farmacología , Antioxidantes/química , Peso Molecular , Polisacáridos Bacterianos/química
5.
Molecules ; 27(21)2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36364123

RESUMEN

Periodontitis, as one of the most common diseases on a global scale, is a public health concern. Microbial resistance to currently available antimicrobial agents is becoming a growing issue in periodontal treatment. As a result, it is critical to develop effective and environmentally friendly biomedical approaches to overcome such challenges. The investigation of Streptomyces rochei MS-37's performance may be the first of its kind as a novel marine actinobacterium for the green biosynthesis of silver nanoparticles (SNPs) and potentials as antibacterial, anti-inflammatory, antibiofilm, and antioxidant candidates suppressing membrane-associated dental infections. Streptomyces rochei MS-37, a new marine actinobacterial strain, was used in this study for the biosynthesis of silver nanoparticles for various biomedical applications. Surface plasmon resonance spectroscopy showed a peak at 429 nm for the SNPs. The SNPs were spherical, tiny (average 23.2 nm by TEM, 59.4 nm by DLS), very stable (-26 mV), and contained capping agents. The minimum inhibitory concentrations of the SNPs that showed potential antibacterial action ranged from 8 to 128 µg/mL. Periodontal pathogens were used to perform qualitative evaluations of microbial adhesion and bacterial penetration through guided tissue regeneration membranes. The findings suggested that the presence of the SNPs could aid in the suppression of membrane-associated infection. Furthermore, when the anti-inflammatory action of the SNPs was tested using nitric oxide radical scavenging capacity and protein denaturation inhibition, it was discovered that the SNPs were extremely efficient at scavenging nitric oxide free radicals and had a strong anti-denaturation impact. The SNPs were found to be more cytotoxic to CAL27 than to human peripheral blood mononuclear cells (PBMCs), with IC50 values of 81.16 µg/mL in PBMCs and 34.03 µg/mL in CAL27. This study's findings open a new avenue for using marine actinobacteria for silver nanoparticle biosynthesis, which holds great promise for a variety of biomedical applications, in particular periodontal treatment.


Asunto(s)
Actinobacteria , Nanopartículas del Metal , Streptomyces , Humanos , Plata/química , Nanopartículas del Metal/química , Leucocitos Mononucleares/metabolismo , Streptomyces/metabolismo , Pruebas de Sensibilidad Microbiana , Antibacterianos/química , Actinobacteria/metabolismo , Extractos Vegetales/química , Espectroscopía Infrarroja por Transformada de Fourier
6.
Microbiol Res ; 262: 127108, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35797944

RESUMEN

Endophytic fungi are known to produce bioactive compounds with the potential to be used as promising drugs to treat a wide range of diseases. To the best of our knowledge, the use of bioactive metabolites derived from endophytic fungi, particularly against multidrug resistant (MDR) pathogens inhabiting burn wounds, has been emphasized for the first time. Therefore, the purpose of this study is to investigate the potential of purified benzoic acid (BA) derived from Neurospora crassa, an endophytic fungus isolated from Lycium shawii, as a promising and alternative safe antimicrobial candidate in wound healing. As a result, benzoic acid, a safe and nontoxic compound, may be a promising candidate for combating clinical MDR pathogens of burn wound infections. In this study, Neurospora crassa strain SSN01 (MW856826) was successfully identified for the first time as a new BA-producing endophytic fungus isolated from Lycium shawii. The concentration of BA in the ethyl acetate extract reached 244 mg/mL. Purified BA had a detrimental effect on the MDR strains tested, and the MDR Staphylococcus aureus strain SA-17 was clearly more susceptible to BA as compared to the other tested MDR bacterial and fungal strains. Toxicological studies on experimental animals were conducted to evaluate the toxicity of BA and a suitable dose regimen for future human use. Oral administration of BA at the highest concentration of 300 µg/kg body weight resulted in nontoxic signs and no mortality. In vivo histopathological examination revealed that BA, as a nontoxic and safe compound, could be a promising candidate for wound healing, combating MDR pathogens of burn wound infections.


Asunto(s)
Antiinfecciosos , Quemaduras , Neurospora crassa , Infección de Heridas , Animales , Antiinfecciosos/farmacología , Ácido Benzoico/farmacología , Endófitos , Humanos , Pruebas de Sensibilidad Microbiana , Cicatrización de Heridas , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología
7.
J Appl Biomed ; 20(2): 45-55, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35727122

RESUMEN

Open wounds are easily susceptible to infection by multi-drug resistant (MDR) pathogens. The emergence of MDR super bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus spp, fungi such as Aspergillus niger and Candida spp, has been identified to significantly increase the incidence rate. Therefore, it is necessary to develop a suitable barrier to prevent infection and enhance wound healing. On the other hand, medicinal plants could represent a significant source of new antimicrobial drugs for combating MDR pathogens. Out of 60 clinical skin burn cases, 51 patients (85%) had polymicrobial infections, while the remaining had monomicrobial infections. Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumonia were identified as the most common bacterial isolates based on morphological and biochemical tests. However, Candida albicans, Candida parasitosis, Candida glabrata, Candida famata, Aspergillus niger, and Exophilia spinifera were the most common fungal isolates found in skin burn cases. MDR classification was reported in 21 of the 39 bacterial isolates and 8 of the 27 fungal isolates. The antimicrobial activity of tested acetonic plant extracts rosemary, henna, and licorice against MDR isolates was compared to the commercial antibiotic agents. Acetonic rosemary extract outperformed henna and licorice extracts in antibacterial activity, while licorice extract outperformed henna and rosemary extracts on antifungal activity. As a result, rosemary and licorice extracts were chosen to prepare a topical cream for further in vivo wound healing and histopathology. Based on the antimicrobial potential of acetonic plant extracts against MDR isolates, BI-41 and FI-17 were chosen for in vivo wound healing. BI-41 stands for the molecularly identified species Pseudomonas aeruginosa SSM-15, while FI-17 stands for molecularly identified species Aspergillus niger SSM-27. In vivo testing showed that both cream formulas had excellent healing properties when administered topically. In vivo histopathological examination revealed that acetonic rosemary and licorice extract could be promising for wound healing, combating MDR pathogens of burn wound infections.


Asunto(s)
Antiinfecciosos , Quemaduras , Antibacterianos/farmacología , Quemaduras/tratamiento farmacológico , Candida , Escherichia coli , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Pseudomonas aeruginosa , Staphylococcus aureus , Cicatrización de Heridas
8.
Front Microbiol ; 13: 833154, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572675

RESUMEN

Biosynthesized silver nanoparticles (Bio-SNPs) were synthesized from the marine actinobacterium strain Streptomyces catenulae M2 and characterized using a variety of techniques, including UV-vis spectrum, fourier transform infrared spectroscopy (FTIR), energy dispersive x-ray (EDX), transmission electron microscopy (TEM), dynamic light scattering (DLS), surface-enhanced Raman spectroscopy (SERS), and zeta potential. The antibacterial activity of Bio-SNPs alone and in combination with antibiotic was evaluated using a microtiter-dilution resazurin assay against multidrug-resistant (MDR) bacteria. Bio-SNPs' minimum inhibitory concentration (MIC) against bacterial strains was determined. To assess the synergistic effect of Bio-SNPs in combination with antibiotics, the Fractional Inhibitory Concentration Index (FICI) was calculated. While the safety of Bio-SNPs in biomedical applications is dependent on their use, the in vitro cytotoxicity of Bio-SNPs on normal human epithelial colon cells (NCM460) and human colorectal adenocarcinoma cells (CaCo2) were evaluated using the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay and cell lactate dehydrogenase (LDH) release. The presence of Bio-SNPs was revealed by UV-vis spectroscopy, which revealed a peak in the Surface Plasmon Resonance (SPR) spectrum at 439.5 nm. Bio-SNPs were spherical in shape and small in size (average 33 nm by TEM, 58.8 nm by DLS), with good stability (-30 mV) and the presence of capping agents. Bio-SNPs had MIC values ranging from 2 to 64 µg/ml against the bacteria tested. The MIC for P. aeruginosa was the lowest (2 µg/ml). Antibiotics have been shown to have a significant synergistic effect when combined with Bio-SNPs against tested bacteria. Bio-SNPs exhibited dose-dependent cytotoxicity against NCM460 and CaCo2 cancer cells, with the latter exhibiting far greater toxicity than  the  former.  NCM460  and CaCo2  cell   viability   decreased   from  99.3 to 95.7% and 92.3 to 61.8%, respectively, whereas LDH leakage increased from 200 to 215 nmol/ml and 261 to 730 nmol/ml, respectively. The half inhibitory concentrations (IC50) for NCM460 and CaCo2 cancer cells were 79.46 and 10.41 µg/ml and 89.4 and 19.3 µg/ml, respectively. Bio-SNPs were found to be biocompatible and to have anti-inflammatory activity. Bio-SNPs are highly appealing for future nanomedicine applications due to their antibacterial and biocompatible properties and their inherent "green" and simple manufacturing.

9.
Front Microbiol ; 13: 803688, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35547125

RESUMEN

The metabolites of lactic acid bacteria (LAB) and bifidobacteria (Bb) have recently received a lot of attention due to their ability to protect interactions in blood and tissues, as well as their biodegradability and biocompatibility in human tissue. Exopolysaccharides (EPS) derived from bacteria have a long history of use in therapeutic and other industrial applications with no adverse effects. In this regard, EPSs were isolated and characterized from LAB and Bb culture supernatants to determine their antioxidant, antitumor, and periodontal regeneration properties. The antioxidant capacity of the EPSs varied with concentration (0.625-20 mg/ml). The highest antioxidant activity was found in LAB: Streptococcus thermophiles DSM 24731-EPS1, Lactobacillus delbrueckii ssp. bulgaricus DSM 20081T-EPS5, Limosilactobacillus fermentum DSM 20049-EPS6, and Bb; Bifidobacterium longum ssp. longum DSM 200707-EPS10. Human breast cancer cells (MCF7), human colon cancer cells (CaCo2), human liver cancer cells (HepG2), and human embryonic kidney 293 (HEK 293) cells were used as controls to assess the antitumor properties of the selected EPSs. According to the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide (MTT) assay, EPS5 had the highest cytotoxicity against MCF7, CaCo2, and HepG2, with IC50 values of 7.91, 10.69, and 9.12 mg/ml, respectively. Lactate dehydrogenase (LDH) activity was significantly higher in cell lines treated with EPS5-IC50 values compared to other EPSs-IC50 values (p < 0.05). Real time (RT)-PCR results showed that EPS5 treatment increased Bax, Caspase 8, Caspase 3, and p53 gene expression. The expression of the BCL2, MCL1, and Vimentin genes, on the other hand, was reduced. The MTT test was used to examine the effect of EPS5 on the viability of human periodontal ligament fibroblast cells (hPDLFCs), and it was discovered that EPS5 increased hPDLFC viability. According to high-performance liquid chromatography (HPLC) analysis, galactose made up 12.5% of EPS5. The findings of this study pave the way for the use of EPS, which hold great promise for a variety of therapeutic purposes such as antioxidant, antitumor, and periodontal regeneration.

10.
J Appl Biomed ; 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35225438

RESUMEN

Thirty-one of sixty dyspeptic patients tested positive for Helicobacter pylori colonization in this study, as determined by histopathology and 16S rRNA. The cytotoxin-associated gene A (cagA) and vacuolating cytotoxin A (vacA) genes were found in 67.7 and 93.5% of H. pylori patients, respectively. The cagA gene was found to be associated with 100% of patients with duodenal erosion and ulceration identified via endoscopy examination. In addition, 86.7% of patients with cancerous and precancerous lesions, glandular atrophy, and intestinal metaplasia identified via histopathology examination. The vacA s1m1 mutation was associated with more severe forms of gastric erosion and ulceration, as well as the presence of precancerous and cancerous lesions. Eighteen (64.3%) of the twenty-eight isolates were classified as multi-drug resistant (MDR) or pan-drug resistant (PDR) H. pylori. Due to a resurgence of interest in alternative therapies derived from plants as a result of H. pylori resistance to the majority of commonly used antibiotics, the inhibitory activity of five essential oils extracted from some commonly used medicinal plants was evaluated in vitro against drug-resistant H. pylori clinical isolates. Cinnamomum zeylanicum essential oil demonstrated the highest anti-H. pylori activity when compared to the other essential oils tested. Cinnamaldehyde was the most abundant compound in C. zeylanicum (65.91%). The toxicological evaluation established the safety of C. zeylanicum oil for human use. As a result, C. zeylanicum essential oil may represent a novel antibacterial agent capable of combating drug-resistant H. pylori carrying cytotoxin genes.

11.
Bioresour Technol ; 351: 126861, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35183728

RESUMEN

MnP-YC4, a newly constructed manganese peroxidase-producing yeast consortium, has been developed to withstand lignin degradation inhibitors while degrading and detoxifying azo dye. MnP-YC4 tolerance to major biomass-derived inhibitors was promising. MnP induced by lignin was found to be highly related to dye decolorization by MnP-YC4. Simulated azo dye-containing wastewater supplemented with a lignin co-substrate (3,5-Dimethoxy-4-hydroxybenzaldehyde) decolorized up to 100, 91, and 76% at final concentrations of 20, 40, and 60%, respectively. MnP-YC4 effectively decolorized the real textile wastewater sample, reaching up to 91.4%, and the COD value decreased significantly during the decolorization, reaching 7160 mg/l within 7 days. A possible dye biodegradation pathway was proposed based on the degradation products identified by UV-vis, FTIR, GC/MS, and HPLC techniques, beginning with azo bond cleavage and eventually mineralized to CO2 and H2O. When compared to the phytotoxic original dye, the phytotoxicity of MnP-YC4 treated dye-containing wastewater samples confirmed the nontoxic nature.


Asunto(s)
Compuestos Azo , Aguas Residuales , Compuestos Azo/metabolismo , Biodegradación Ambiental , Colorantes/metabolismo , Lignina , Peroxidasas , Saccharomyces cerevisiae/metabolismo , Industria Textil , Textiles , Aguas Residuales/química
12.
BMJ Open ; 12(2): e049741, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35168963

RESUMEN

OBJECTIVES: To evaluate the effectiveness of a tailored multidimensional intervention in reducing the care burden of family caregivers of stroke survivors. This intervention considered caregivers' perceived needs and incorporated three evidence-based dimensions (psychoeducation, skill-building and peer support). DESIGN: A prospective randomised control trial. SETTING: A community-based study conducted in Egypt. PARTICIPANTS: A total of 110 caregivers aged ≥18 years who cared for a survivor within 6 months of stroke, with modified Rankin Scale scores of 3-5, and without other physical disabilities or terminal illnesses were recruited between December 2019 and May 2020. Participants were assigned to the intervention group (IG; n=55) and control group (CG; n=55) through open-label, parallel 1:1 randomisation. INTERVENTION: The IG was provided with tailored multidimensional interventions for 6 months until November 2020, including three home visits, six home-based telephone calls and one peer-support session. The CG received simple educational instructions at a single visit. OUTCOME: The participants completed the Zarit Burden Interview (primary outcome) and the WHO Quality of Life-BREF (secondary outcome) before the intervention (T0), at 3 months (T1) and at 6 months (T2). RESULTS: No differences were observed between the characteristics of the groups at baseline (T0). The independent t-test showed no significant differences in the care burden and Quality of Life (QoL) at T1 and T2 between the groups. The intervention had no significant effect on the outcomes between or within groups over time, as shown by the repeated-measures analysis of variance. However, the group and time interaction had significant main effects on caregivers' QoL (psychological and social domains). CONCLUSION: The main results showed that participants in the IG did not experience an improvement in the main outcomes. Nevertheless, the improvement in the psychological and social domains may have been attributed to our intervention. TRIAL REGISTRATION NUMBER: NCT04211662.


Asunto(s)
Cuidadores , Accidente Cerebrovascular , Adolescente , Adulto , Carga del Cuidador , Cuidadores/psicología , Humanos , Estudios Prospectivos , Calidad de Vida , Accidente Cerebrovascular/terapia , Sobrevivientes
13.
Pathogens ; 12(1)2022 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-36678381

RESUMEN

Background: A urinary tract infection (UTI) resulting from multidrug-resistant (MDR) enterococci is a common disease with few therapeutic options. About 15% of urinary tract infections are caused by biofilm-producing Enterococcus spp. Therefore, the objective of this study was to identify the MDR enterococci associated with UTIs and assess their potential to produce biofilms. Methods: Thirty Enterococcus isolates were obtained from urine samples collected from UTI patients at King Abdulaziz Specialist Hospital in Taif, Saudi Arabia. The antimicrobial resistance profiles of the isolates were evaluated using disk diffusion techniques against 15 antimicrobial agents. Two techniques, Congo red agar (CRA) and a microtiter plate (MTP), were used to assess the potential of the isolates to produce biofilms. The enterococcal isolates were screened for biofilm-related genes, esp; ebpA; and ebpB, using the PCR method. Results: The molecular identification of the collected bacteria revealed the presence of 73.3% Enterococcus faecalis and 26.6% Enterococcus faecium. The antibiotic susceptibility test revealed that all the tested Enterococcus spp. were resistant to all antimicrobials except for linezolid and tigecycline. Additionally, by employing the CRA and MTP techniques, 76.6% and 100% of the Enterococcus isolates were able to generate biofilms, respectively. In terms of the association between the antibiotic resistance and biofilm's formation, it was observed that isolates capable of creating strong biofilms were extremely resistant to most of the antibiotics tested. The obtained data showed that all the tested isolates had biofilm-encoding genes. Conclusions: Our research revealed that the biofilm-producing enterococci bacteria that causes urinary tract infections were resistant to antibiotics. Therefore, it is necessary to seek other pharmacological treatments if antibiotic medicine fails.

14.
Biotechnol Biofuels ; 14(1): 229, 2021 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-34863263

RESUMEN

BACKGROUND: The ability of oxidative enzyme-producing micro-organisms to efficiently valorize organic pollutants is critical in this context. Yeasts are promising enzyme producers with potential applications in waste management, while lipid accumulation offers significant bioenergy production opportunities. The aim of this study was to explore manganese peroxidase-producing oleaginous yeasts inhabiting the guts of wood-feeding termites for azo dye decolorization, tolerating lignocellulose degradation inhibitors, and biodiesel production. RESULTS: Out of 38 yeast isolates screened from wood-feeding termite gut symbionts, nine isolates exhibited high levels of extracellular manganese peroxidase (MnP) activity ranged between 23 and 27 U/mL after 5 days of incubation in an optimal substrate. Of these MnP-producing yeasts, four strains had lipid accumulation greater than 20% (oleaginous nature), with Meyerozyma caribbica SSA1654 having the highest lipid content (47.25%, w/w). In terms of tolerance to lignocellulose degradation inhibitors, the four MnP-producing oleaginous yeast strains could grow in the presence of furfural, 5-hydroxymethyl furfural, acetic acid, vanillin, and formic acid in the tested range. M. caribbica SSA1654 showed the highest tolerance to furfural (1.0 g/L), 5-hydroxymethyl furfural (2.5 g/L) and vanillin (2.0 g/L). Furthermore, M. caribbica SSA1654 could grow in the presence of 2.5 g/L acetic acid but grew moderately. Furfural and formic acid had a significant inhibitory effect on lipid accumulation by M. caribbica SSA1654, compared to the other lignocellulose degradation inhibitors tested. On the other hand, a new MnP-producing oleaginous yeast consortium designated as NYC-1 was constructed. This consortium demonstrated effective decolorization of all individual azo dyes tested within 24 h, up to a dye concentration of 250 mg/L. The NYC-1 consortium's decolorization performance against Acid Orange 7 (AO7) was investigated under the influence of several parameters, such as temperature, pH, salt concentration, and co-substrates (e.g., carbon, nitrogen, or agricultural wastes). The main physicochemical properties of biodiesel produced by AO7-degraded NYC-1 consortium were estimated and the results were compared to those obtained from international standards. CONCLUSION: The findings of this study open up a new avenue for using peroxidase-producing oleaginous yeasts inhabiting wood-feeding termite gut symbionts, which hold great promise for the remediation of recalcitrant azo dye wastewater and lignocellulosic biomass for biofuel production.

15.
Plants (Basel) ; 10(12)2021 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-34961281

RESUMEN

The present study aims to evaluate the antioxidant and antimicrobial activity of essential oils (EO) extracted from safflower plants grown in the absence and presence of NaCl, 50 mM. Plants treated with 50 mM of NaCl showed decreases in root, stem, and leaf dry weight. Results of the essential oils showed that roots have a higher EO yield than leaves and stems. Salinity caused a decrease in this yield in roots and leaves but not in stems. The compounds identified in the EO extracted from these organs belong to seven chemical classes of which the dominant class is the sesquiterpene hydrocarbons. The chemotype of C. tinctorius EO is variable depending on the organ and the treatment. The safflower essential oils showed low antioxidant, antiradical, and iron-reducing activities compared to those of the positive control (BHT). In an antifungal activity test, only two strains, Aspergillus niger and Candida albicans, were found to be highly sensitive to these oils as they showed almost total inhibition of their growth. For antibacterial activity, safflower EOs showed significant antimicrobial activity against Bacillus subtilis, Bacillus cereus, and Xanthomonas campestris in both control and NaCl-treated plants: for these three strains, total inhibition of growth was noted at 50,000 ppm of EO in leaves and roots; whereas for stems, total inhibition was noted only for the third strain (Xanthomonas campestris). For other strains, this inhibition was variable and weak. Salt was found to have no effect on the activities of safflower EOs.

16.
Front Microbiol ; 12: 648560, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34616370

RESUMEN

Burn wound infections with multidrug-resistant (MDR) bacteria are shown in many countries as severe widespread health threats. Consequently, attention has been devoted to new nanoparticle-based materials in the field of antimicrobial chemotherapy for burn wound infections. This study aimed to evaluate both in vitro and in vivo efficacies of nanoparticle-antibiotic combinations as new classes of materials subjected against MDR Pseudomonas aeruginosa. Out of 40 Gram-negative isolates, 23 P. aeruginosa were recovered from patients with burn wound infections attending different hospitals in Tanta, Egypt. The susceptibility test revealed that 95.7% of P. aeruginosa isolates were MDR with a high incidence of resistance against carbenicillin. Antibacterial activities of silver nanoparticles (Ag-NPs) against the isolates examined showed various inhibition zone diameters ranging from 11 to 17 mm. Strong synergistic efficacy of neomycin was reported in combination with Ag-NPs against MDR P. aeruginosa P8 and P14 isolates. The in vivo effectiveness of various pharmaceutical formulations prepared from a combination of neomycin antibiotic with Ag-NPs in the treatment of induced bacterially infected mice burns showed that maximum healing activity along with faster wound contraction reported with the combination of neomycin-Ag-NPs in the spray formulation. Generally, data indicated that incorporating Ag-NPs in combination with certain antibiotics may be a new, promising application for wound treatments, especially burns infected with MDR P. aeruginosa.

17.
J Hazard Mater ; 418: 126091, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34118544

RESUMEN

Lignocellulosic biomass represents an unlimited and ubiquitous energy source, which can effectively address current global challenges, including climate change, greenhouse gas emissions, and increased energy demand. However, lignocellulose recalcitrance hinders microbial degradation, especially in case of contaminated materials such as creosote (CRO)-treated wood, which necessitates appropriate processing in order to eliminate pollution. This study might be the first to explore a novel bacterial consortium SST-4, for decomposing birchwood sawdust, capable of concurrently degrading lignocellulose and CRO compounds. Afterwards, SST-4 which stands for molecularly identified bacterial strains Acinetobacter calcoaceticus BSW-11, Shewanella putrefaciens BSW-18, Bacillus cereus BSW-23, and Novosphingobium taihuense BSW-25 was evaluated in terms of biological sawdust pre-treatment, resulting in effective lignocellulose degradation and 100% removal of phenol and naphthalene. Subsequently, the maximum biogas production observed was 18.7 L/kg VS, while cumulative methane production was 162.8 L/kg VS, compared to 88.5 without microbial pre-treatment. The cumulative energy production from AD-I and AD-II through biomethanation was calculated as 3177.1 and 5843.6 KJ/kg, respectively. The pretreatment process exhibited a significant increase in the energy yield by 83.9%. Lastly, effective CRO detoxification was achieved with EC50 values exceeding 90%, showing the potential for an integrated process of effective contaminated wood management and bioenergy production.


Asunto(s)
Consorcios Microbianos , Sphingomonadaceae , Anaerobiosis , Biocombustibles/análisis , Biomasa , Creosota , Lignina/metabolismo , Metano , Sphingomonadaceae/metabolismo , Madera/química
19.
Biotechnol Biofuels ; 14(1): 61, 2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-33685508

RESUMEN

BACKGROUND: Textile industry represents one prevalent activity worldwide, generating large amounts of highly contaminated and rich in azo dyes wastewater, with severe effects on natural ecosystems and public health. However, an effective and environmentally friendly treatment method has not yet been implemented, while concurrently, the increasing demand of modern societies for adequate and sustainable energy supply still remains a global challenge. Under this scope, the purpose of the present study was to isolate promising species of yeasts inhabiting wood-feeding termite guts, for combined azo dyes and textile wastewater bioremediation, along with biodiesel production. RESULTS: Thirty-eight yeast strains were isolated, molecularly identified and subsequently tested for desired enzymatic activity, lipid accumulation, and tolerance to lignin-derived metabolites. The most promising species were then used for construction of a novel yeast consortium, which was further evaluated for azo dyes degradation, under various culture conditions, dye levels, as well as upon the addition of heavy metals, different carbon and nitrogen sources, and lastly agro-waste as an inexpensive and environmentally friendly substrate alternative. The novel yeast consortium, NYC-1, which was constructed included the manganese-dependent peroxidase producing oleaginous strains Meyerozyma caribbica, Meyerozyma guilliermondii, Debaryomyces hansenii, and Vanrija humicola, and showed efficient azo dyes decolorization, which was further enhanced depending on the incubation conditions. Furthermore, enzymatic activity, fatty acid profile and biodiesel properties were thoroughly investigated. Lastly, a dye degradation pathway coupled to biodiesel production was proposed, including the formation of phenol-based products, instead of toxic aromatic amines. CONCLUSION: In total, this study might be the first to explore the application of MnP and lipid-accumulating yeasts for coupling dye degradation and biodiesel production.

20.
Int J Food Microbiol ; 344: 109116, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33676332

RESUMEN

Staphylococcus aureus is among the most common zoonotic pathogens originating from animals consumed as food, especially raw chicken meat (RCM). As far as we know, this might be the first report that explores the efficacy of metal oxide nanoparticles (MONPs), such as zinc peroxide nanoparticles (ZnO2-NPs), zinc oxide nanoparticles (ZnO-NPs), and titanium dioxide nanoparticles (TiO2-NPs) against multidrug resistant (MDR) and/or pandrug resistant (PDR) S. aureus strains with a strong biofilm-producing ability isolated from RCM and giblets. The overall prevalence of coagulase-positive staphylococci was 21%, with a contamination level range between 102 and 104 CFU/g. The incidence of virulence genes See (21/36), pvl (16/36), clfA (15/36), sec (12/36), tst (12/36), and sea (11/36) among S. aureus strains were relatively higher those of seb, sed, fnbA, and fnbB. For antimicrobial resistance gene distribution, most strains harbored the blaZ gene (25/36), aacA-aphD gene (24/36), mecA gene (22/36), vanA gene (20/36), and apmA gene (20/36) confirmed the prevalence of MDR among S. aureus of RCM products. However, cfr (11/36), spc (9/36), and aadE (7/36) showed a relatively lower existence. The data of antibiogram resistance profiles was noticeably heterogeneous (25 patterns) with 32 MDR and four PDR S. aureus strains. All tested strains had a very high MAR index value (>0.2) except the P11 pattern (GEN, MXF, PMB), which showed a MAR index of 0.19. Among the strong biofilm-producing ability (BPA), 14 (70%) strains were isolated from wet markets, while only six strong BPA strains were isolated from supermarkets. The mean values of BPA ranged from 2.613 ± 0.04 to 11.013 ± 0.05. Clearly, ZnO2-NPs show significant inhibitory activity against S. aureus strains compared with those produced by the action of ZnO-NPs and TiO2-NPs. The results of anti-inflammatory activity suggest ZnO2-NPs as a lead compound for designing an alternative antimicrobial agent against drug-resistant and strong biofilm-producing S. aureus isolates from retail RCM and giblets.


Asunto(s)
Antibacterianos/farmacología , Contaminación de Alimentos/prevención & control , Staphylococcus aureus/crecimiento & desarrollo , Titanio/farmacología , Óxido de Zinc/farmacología , Animales , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Pollos/microbiología , Farmacorresistencia Bacteriana Múltiple/genética , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Carne/microbiología , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/prevención & control , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Virulencia/genética
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