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1.
Front Microbiol ; 15: 1345478, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559346

RESUMO

Antimicrobial resistance is one of the largest medical challenges because of the rising frequency of opportunistic human microbial infections across the globe. This study aimed to extract chitosan from the exoskeletons of dead bees and load it with bee venom (commercially available as Apitoxin [Api]). Then, the ionotropic gelation method would be used to form nanoparticles that could be a novel drug-delivery system that might eradicate eight common human pathogens (i.e., two fungal and six bacteria strains). It might also be used to treat the human colon cancer cell line (Caco2 ATCC ATP-37) and human liver cancer cell line (HepG2ATCC HB-8065) cancer cell lines. The x-ray diffraction (XRD), Fourier transform infrared (FTIR), and dynamic light scattering (DLS) properties, ζ-potentials, and surface appearances of the nanoparticles were evaluated by transmission electron microscopy (TEM). FTIR and XRD validated that the Api was successfully encapsulated in the chitosan nanoparticles (ChB NPs). According to the TEM, the ChB NPs and the ChB NPs loaded with Apitoxin (Api@ChB NPs) had a spherical shape and uniform size distribution, with non-aggregation, for an average size of approximately 182 and 274 ± 3.8 nm, respectively, and their Zeta potential values were 37.8 ± 1.2 mV and - 10.9 mV, respectively. The Api@ChB NPs had the greatest inhibitory effect against all tested strains compared with the ChB NPs and Api alone. The minimum inhibitory concentrations (MICs) of the Api, ChB NPs, and Api@ChB NPs were evaluated against the offer mentioned colony forming units (CFU/mL), and their lowest MIC values were 30, 25, and 12.5 µg mL-1, respectively, against Enterococcus faecalis. Identifiable morphological features of apoptosis were observed by 3 T3 Phototox software after Api@ChB NPs had been used to treat the normal Vero ATCC CCL-81, Caco2 ATCC ATP-37, and HepG2 ATCC HB-8065 cancer cell lines for 24 h. The morphological changes were clear in a concentration-dependent manner, and the ability of the cells was 250 to 500 µg mL-1. These results revealed that Api@ChB NPs may be a promising natural nanotreatment for common human pathogens.

2.
Front Microbiol ; 15: 1374466, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646632

RESUMO

Pseudomonas aeruginosa, a Gram-negative bacterium, is recognized for its adaptability and opportunistic nature. It poses a substantial challenge in clinical settings due to its complicated antibiotic resistance mechanisms, biofilm formation, and capacity for persistent infections in both animal and human hosts. Recent studies revealed a potential zoonotic transmission of P. aeruginosa between animals, the environment, and human populations which highlights awareness of this microbe. Implementation of the One Health approach, which underscores the connection between human, animal, and environmental health, we aim to offer a comprehensive perspective on the current landscape of P. aeruginosa management. This review presents innovative strategies designed to counteract P. aeruginosa infections. Traditional antibiotics, while effective in many cases, are increasingly compromised by the development of multidrug-resistant strains. Non-antibiotic avenues, such as quorum sensing inhibition, phage therapy, and nanoparticle-based treatments, are emerging as promising alternatives. However, their clinical application encounters obstacles like cost, side effects, and safety concerns. Effectively addressing P. aeruginosa infections necessitates persistent research efforts, advancements in clinical development, and a comprehension of host-pathogen interactions to deal with this resilient pathogen.

3.
Front Microbiol ; 14: 1271733, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869654

RESUMO

Introduction: Although carbapenemases are frequently reported in resistant A. baumannii clinical isolates, other chromosomally mediated elements of resistance that are considered essential are frequently underestimated. Having a wide substrate range, multidrug efflux pumps frequently underlie antibiotic treatment failure. Recognizing and exploiting variations in multidrug efflux pumps and penicillin-binding proteins (PBPs) is an essential approach in new antibiotic drug discovery and engineering to meet the growing challenge of multidrug-resistant Gram-negative bacteria. Methods: A total of 980 whole genome sequences of A. baumannii were analyzed. Nucleotide sequences for the genes studied were queried against a custom database of FASTA sequences using the Bacterial and Viral Bioinformatics Resource Center (BV-BRC) system. The correlation between different variants and carbapenem Minimum Inhibitory Concentrations (MICs) was studied. PROVEAN and I-Mutant predictor suites were used to predict the effect of the studied amino acid substitutions on protein function and protein stability. Both PsiPred and FUpred were used for domain and secondary structure prediction. Phylogenetic reconstruction was performed using SANS serif and then visualized using iTOL and Phandango. Results: Exhibiting the highest detection rate, AdeB codes for an important efflux-pump structural protein. T48V, T584I, and P660Q were important variants identified in the AdeB-predicted multidrug efflux transporter pore domains. These can act as probable targets for designing new efflux-pump inhibitors. Each of AdeC Q239L and AdeS D167N can also act as probable targets for restoring carbapenem susceptibility. Membrane proteins appear to have lower predictive potential than efflux pump-related changes. OprB and OprD changes show a greater effect than OmpA, OmpW, Omp33, and CarO changes on carbapenem susceptibility. Functional and statistical evidence make the variants T636A and S382N at PBP1a good markers for imipenem susceptibility and potential important drug targets that can modify imipenem resistance. In addition, PBP3_370, PBP1a_T636A, and PBP1a_S382N may act as potential drug targets that can be exploited to counteract imipenem resistance. Conclusion: The study presents a comprehensive epidemiologic and statistical analysis of potential membrane proteins and efflux-pump variants related to carbapenem susceptibility in A. baumannii, shedding light on their clinical utility as diagnostic markers and treatment modification targets for more focused studies of candidate elements.

4.
Antibiotics (Basel) ; 12(10)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37887215

RESUMO

Pseudomonas aeruginosa is notorious for its ability to develop a high level of resistance to antimicrobial agents. Resistance-nodulation-division (RND) efflux pumps could mediate drug resistance in P. aeruginosa. The present study aimed to evaluate the antibacterial and anti-efflux activities of cinnamon essential oil either alone or combined with ciprofloxacin against drug resistant P. aeruginosa originated from human and animal sources. The results revealed that 73.91% of the examined samples were positive for P. aeruginosa; among them, 77.78% were of human source and 72.73% were recovered from animal samples. According to the antimicrobial resistance profile, 48.73% of the isolates were multidrug-resistant (MDR), 9.2% were extensive drug-resistant (XDR), and 0.84% were pan drug-resistant (PDR). The antimicrobial potential of cinnamon oil against eleven XDR and one PDR P. aeruginosa isolates was assessed by the agar well diffusion assay and broth microdilution technique. The results showed strong antibacterial activity of cinnamon oil against all tested P. aeruginosa isolates with inhibition zones' diameters ranging from 34 to 50 mm. Moreover, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of cinnamon oil against P. aeruginosa isolates ranged from 0.0562-0.225 µg/mL and 0.1125-0.225 µg/mL, respectively. The cinnamon oil was further used to evaluate its anti-efflux activity against drug-resistant P. aeruginosa by phenotypic and genotypic assays. The cartwheel test revealed diminished efflux pump activity post cinnamon oil exposure by two-fold indicating its reasonable impact. Moreover, the real-time quantitative polymerase chain reaction (RT-qPCR) results demonstrated a significant (p < 0.05) decrease in the expression levels of MexA and MexB genes of P. aeruginosa isolates treated with cinnamon oil when compared to the non-treated ones (fold changes values ranged from 0.4204-0.7474 for MexA and 0.2793-0.4118 for MexB). In conclusion, we suggested the therapeutic use of cinnamon oil as a promising antibacterial and anti-efflux agent against drug-resistant P. aeruginosa.

5.
Poult Sci ; 102(11): 102889, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37666144

RESUMO

Locomotor disorders caused by multidrug-resistant (MDR) bacterial pathogens denote one of the most detrimental issues that collectively threaten the poultry industry leading to pronounced economic losses across the world. Hence, searching for effective alternatives, especially those extracted from plant origins became of great priority targeting a partial or complete replacement of chemical antimicrobials to tackle their developing resistance. Therefore, we aimed to determine the prevalence and antimicrobial resistance of Staphylococcus aureus (S. aureus), Salmonella species, Mycoplasma synoviae (M. synoviae), and Escherichia coli (E. coli) recovered from 500 broilers and ducks (250 each) with locomotor disorders in various farms in Dakahlia and Sharkia Governorates, Egypt. Additionally, we assessed, for the first time, the in vitro antimicrobial effectiveness of marjoram, garlic, ginger and cinnamon essential oils (EOs) against MDR and multivirulent bacterial isolates as well as the in vivo efficiency of the most effective antibiotics and EOs either separately or in combination in the treatment of experimentally induced poultry leg disorders. The overall prevalence rates of S. aureus, E. coli, Salmonella species, and M. synoviae were 54, 48, 36, and 2%, respectively. Salmonella species and S. aureus prevailed among ducks and broilers (36 and 76%, respectively). Notably, MDR was observed in 100, 91.7, 81.1, and 78.5% of M. synoviae, E. coli, Salmonella, and S. aureus isolates, respectively. Our in vitro results displayed that marjoram was the most forceful EO against MDR and multivirulent chicken vancomycin-resistant S. aureus (VRSA) and duck S. Typhimurium isolates. The current in vivo results declared that marjoram in combination with florfenicol or amoxicillin/clavulanic acid succeeded in relieving the induced duck and chicken leg disorders caused by S. Typhimurium and VRSA, respectively. This was evidenced by improvement in the clinical and histopathological pictures with a reduction of bacterial loads in the experimental birds. Our encountered successful in vitro and in vivo synergistic effectiveness of marjoram combined with florfenicol or amoxicillin/clavulanic acid recommends their therapeutic application for leg disorders and offers opportunities for reducing the antibiotics usage in the poultry industry.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Galinhas/microbiologia , Escherichia coli , Staphylococcus aureus , Aves Domésticas , Anti-Infecciosos/farmacologia , Salmonella , Patos/microbiologia , Infecções Estafilocócicas/veterinária , Ácido Clavulânico/farmacologia , Amoxicilina/farmacologia , Testes de Sensibilidade Microbiana/veterinária
6.
Front Microbiol ; 14: 1142646, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143540

RESUMO

In recent investigations, secondary bacterial infections were found to be strongly related to mortality in COVID-19 patients. In addition, Pseudomonas aeruginosa and Methicillin-resistant Staphylococcus aureus (MRSA) bacteria played an important role in the series of bacterial infections that accompany infection in COVID-19. The objective of the present study was to investigate the ability of biosynthesized silver nanoparticles from strawberries (Fragaria ananassa L.) leaf extract without a chemical catalyst to inhibit Gram-negative P. aeruginosa and Gram-positive Staph aureus isolated from COVID-19 patient's sputum. A wide range of measurements was performed on the synthesized AgNPs, including UV-vis, SEM, TEM, EDX, DLS, ζ -potential, XRD, and FTIR. UV-Visible spectral showed the absorbance at the wavelength 398 nm with an increase in the color intensity of the mixture after 8 h passed at the time of preparation confirming the high stability of the FA-AgNPs in the dark at room temperature. SEM and TEM measurements confirmed AgNPs with size ranges of ∼40-∼50 nm, whereas the DLS study confirmed their average hydrodynamic size as ∼53 nm. Furthermore, Ag NPs. EDX analysis showed the presence of the following elements: oxygen (40.46%), and silver (59.54%). Biosynthesized FA-AgNPs (ζ = -17.5 ± 3.1 mV) showed concentration-dependent antimicrobial activity for 48 h in both pathogenic strains. MTT tests showed concentration-dependent and line-specific effects of FA-AgNPs on cancer MCF-7 and normal liver WRL-68 cell cultures. According to the results, synthetic FA-AgNPs obtained through an environmentally friendly biological process are inexpensive and may inhibit the growth of bacteria isolated from COVID-19 patients.

7.
Drug Deliv ; 29(1): 1536-1548, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35612292

RESUMO

Certain anticancer agents selectively target the nucleus of cancer cells. One such drug is 2-methoxyestradiol (2ME), which is used for treating lung cancer. To improve the therapeutic effectiveness of these agents, many new methods have been devised. 2ME was entrapped into the core of hydrophobic invasomes (INVA) covered with Phospholipon 90G and apamin (APA). The Box-Behnken statistical design was implemented to enhance the composition. Using Design-Expert software (Stat-Ease Inc., Minneapolis, MN), the INVA component quantities were optimized to obtain spherical particles with the smallest size, that is, a diameter of 167.8 nm. 2ME-INVA-APA significantly inhibited A549 cells and exhibited IC50 of 1.15 ± 0.04 µg/mL, which is lower than raw 2ME (IC50 5.6 ± 0.2 µg/mL). Post 2ME-INVA-APA administration, a significant rise in cell death and necrosis was seen among the A549 cells compared to those treated with plain formula or 2ME alone. This effect was indicated by increased Bax expression and reduced Bcl-2 expression, as well as mitochondrial membrane potential loss. Moreover, the cell cycle analysis showed that 2ME-INVA-APA arrests the G2-M phase of the A549 cells. Additionally, it was observed that the micellar formulation of the drug increased the cell count in pre-G1, thereby exhibiting phenomenal apoptotic potential. Furthermore, it up-regulates caspase-9 and p53 and downregulates TNF-α and NF-κß. Collectively, these findings showed that our optimized 2ME-INVA-APA could easily seep through the cell membrane and induce apoptosis in relatively low doses.


Assuntos
Apoptose , Neoplasias Pulmonares , 2-Metoxiestradiol/farmacologia , Células A549 , Apamina/farmacologia , Estradiol/farmacologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico
8.
Food Sci Nutr ; 10(2): 470-476, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35154683

RESUMO

Food additives have been shown to help regulate or prevent the spread of microbes during food manufacturing. Phloxine B, nisin, and sorbic acid were tested to see whether they had a synergistic impact on the inactivation of Bacillus cereus and Staphylococcus aureus, respectively. The combination of phloxine B and nisin had a synergistic interaction (FICI: 0.25-0.50) against B. cereus, where it demonstrated an additive effect among the three combinations examined (FICI: 0.91). A time-kill test was used in both cases to verify that a food additive combination has synergistic antibacterial action against B. cereus and S. aureus. B. cereus had a 50% reduction in bacterial colony count after 10 h, whereas S. aureus had a 60% reduction after 6 h of their independent impacts after 48 h. Phloxine B, nisin, and sorbic acid demonstrated synergistic antibacterial action and might be used as a source of safe and potent antibacterial agents in the pharmaceutical and food industries.

9.
Pharmaceutics ; 13(12)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34959424

RESUMO

Lung cancer is a dangerous type of cancer in men and the third leading cause of cancer-related death in women, behind breast and colorectal cancers. Thymoquinone (THQ), a main compound in black seed essential oils, has a variety of beneficial effects, including antiproliferative, anti-inflammatory, and antioxidant properties. On the other hand, scorpion venom peptides (SV) induce apoptosis in the cancer cells, making it a promising anticancer agent. THQ, SV, and Phospholipon® 90H (PL) were incorporated in a nano-based delivery platform to assess THQ's cellular uptake and antiproliferative efficacy against a lung cancer cell line derived from human alveolar epithelial cells (A549). Several nanovesicles were prepared and optimized using factorial experimental design. The optimized phytosome formulation contained 79.0 mg of PL and 170.0 mg of SV, with vesicle size and zeta potential of 209.9 nm and 21.1 mV, respectively. The IC50 values revealed that A549 cells were significantly more sensitive to the THQ formula than the plain formula and THQ. Cell cycle analysis revealed that THQ formula treatment resulted in significant cell cycle arrest at the S phase, increasing cell population in this phase by 22.1%. Furthermore, the THQ formula greatly increased cell apoptosis (25.17%) when compared to the untreated control (1.76%), plain formula (11.96%), or THQ alone (13.18%). The results also indicated that treatment with THQ formula significantly increased caspase-3, Bax, Bcl-2, and p53 mRNA expression compared to plain formula and THQ. In terms of the inflammatory markers, THQ formula significantly reduced the activity of TNF-α and NF-κB in comparison with the plain formula and THQ only. Overall, the findings from the study proved that a phytosome formulation of THQ could be a promising therapeutic approach for the treatment of lung adenocarcinoma.

10.
Front Microbiol ; 8: 531, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28400767

RESUMO

The outer membrane (OM) of Gram-negative pathogenic bacteria is a key structure in host-pathogen interactions that contains a plethora of proteins, performing a range of functions including adhesion, nutrient uptake, export of effectors and interaction with innate and adaptive components of the immune system. In addition, the OM can exclude drugs and thus contribute to antimicrobial resistance. The OM of the food-borne pathogen Campylobacter jejuni contains porins, adhesins and other virulence factors that must be specifically localized to this membrane, but the protein sorting mechanisms involved are only partially understood. In particular, chaperones are required to ferry OM proteins across the periplasm after they emerge from the Sec translocation system. The SurA-related chaperone PEB4 (Cj0596) is the only protein with a proven role in OM biogenesis and integrity in C. jejuni. In this work, we have constructed a set of isogenic deletion mutants in genes encoding both known and predicted chaperones (cj0596, cj0694, cj1069, cj1228c, and cj1289) using NCTC 11168H as the parental strain. These mutants were characterized using a range of assays to determine effects on growth, agglutination, biofilm formation, membrane permeability and hydrophobicity. We focused on Cj1289 and Cj0694, which our previous work suggested possessed both chaperone and peptidyl-proyl cis/trans isomerase (PPIase) domains. Mutants in either cj1289 or cj0694 showed growth defects, increased motility, agglutination and biofilm formation and severe OM permeability defects as measured by a lysozyme accessibility assay, that were comparable to those exhibited by the isogenic peb4 mutant. 2D-gel comparisons showed a general decrease in OM proteins in these mutants. We heterologously overproduced and purified Cj0694 and obtained evidence that this protein was an active PPIase, as judged by its acceleration of the refolding rate of reduced and alkylated ribonuclease T1 and that it also possessed holdase-type chaperone activity. Cj0694 is most similar to the PpiD class of chaperones but is unusual in possessing PPIase activity. Taken together, our data show that in addition to PEB4, Cj1289 (SalC; SurA-like chaperone) and Cj0694 (PpiD) are also key proteins involved in OM biogenesis and integrity in C. jejuni.

11.
Saudi Med J ; 36(7): 807-12, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26108584

RESUMO

OBJECTIVES: To identify Methicillin-resistant Staphylococcus aureus (MRSA) nasal carriage status among medical students during their clinical rotations. METHODS: This cross-sectional study detected the prevalence of MRSA among medical students at King Abdulaziz University (KAU), Jeddah, Saudi Arabia, using molecular approaches. Nasal swabs were collected from 150 internship and sixth-year medical students between September 2014 and January 2015, and compared with the control group of 32 third-year medical students who were not exposed to clinical work. Polymerase chain reaction (PCR) screening was performed to identify Staphylococcus aureus (S. aureus) nucgene, and an additional PCR was performed on S. aureus positive samples to detect the presence of mecA gene. RESULTS: Out of 150 students screened, 38 were nasal carriers of S. aureus. The prevalence of methicillin-sensitive S. aureus (MSSA) carriers was 18.7% (n=28), whereas 10 students (6.7%) were mecA-positive, representing MRSA carriers. Interns carry MRSA more than 6th year students and students who were not exposed to clinical work (p less than 0.05), while MSSA is found more in students who were not exposed to clinical work (p less than 0.01). CONCLUSION: We found MRSA carriers among medical students at KAU, which showed a possible contribution of this group to transmit infection to hospitalized patients. Medical students must receive sufficient knowledge regarding control measures to avoid spread of this infection in hospitals.


Assuntos
Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Nariz/microbiologia , Infecções Estafilocócicas/epidemiologia , Estudantes de Medicina , Portador Sadio , Estudos de Casos e Controles , Humanos , Prevalência , Arábia Saudita/epidemiologia , Infecções Estafilocócicas/microbiologia
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