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1.
Parasites Hosts Dis ; 62(3): 351-364, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39218634

RÉSUMÉ

The gut microbiome plays an essential role in host immune responses, including allergic reactions. However, commensal gut microbiota is extremely sensitive to antibiotics and excessive usage can cause microbial dysbiosis. Herein, we investigated how changes in the gut microbiome induced by ampicillin affected the production of IgG1 and IgG2a antibodies in mice subsequently exposed to Anisakis pegreffii antigens. Ampicillin treatment caused a notable change in the gut microbiome as shown by changes in both alpha and beta diversity indexes. In a 1-dimensional immunoblot using Anisakis-specific anti-mouse IgG1, a 56-kDa band corresponding to an unnamed Anisakis protein was detected using mass spectrometry analysis only in ampicillin-treated mice. In the Anisakis-specific anti-mouse IgG2a-probed immunoblot, a 70-kDa band corresponding to heat shock protein 70 (HSP70) was only detected in ampicillin-treated and Anisakis-immunized mice. A 2-dimensional immunoblot against Anisakis extract with immunized mouse sera demonstrated altered spot patterns in both groups. Our results showed that ampicillin treatment altered the gut microbiome composition in mice, changing the immunization response to antigens from A. pegreffii. This research could serve as a basis for developing vaccines or allergy immunotherapies against parasitic infections.


Sujet(s)
Ampicilline , Anisakis , Microbiome gastro-intestinal , Immunoglobuline G , Animaux , Anisakis/immunologie , Microbiome gastro-intestinal/effets des médicaments et des substances chimiques , Microbiome gastro-intestinal/immunologie , Ampicilline/pharmacologie , Souris , Immunoglobuline G/immunologie , Immunoglobuline G/sang , Antigènes d'helminthe/immunologie , Femelle , Anisakiase/immunologie , Anisakiase/parasitologie , Anticorps antihelminthe/immunologie , Immunisation
2.
Article de Anglais | MEDLINE | ID: mdl-39092644

RÉSUMÉ

BACKGROUND: A biofilm refers to a community of microbial cells that adhere to surfaces that are surrounded by an extracellular polymeric substance. Bacteria employ various defence mechanisms, including biofilm formation, to enhance their survival and resistance against antibiotics. OBJECTIVE: The current study aims to investigate the resistance patterns of Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) in both biofilms and their planktonic forms. METHODS: E. coli and B. subtilis were used to compare resistance patterns in biofilms versus planktonic forms of bacteria. An antibiotic disc diffusion test was performed to check the resistance pattern of biofilm and planktonic bacteria against different antibiotics such as penicillin G, streptomycin, and ampicillin. Biofilm formation and its validation were done by using quantitative (microtiter plate assay) and qualitative analysis (Congo red agar media). RESULTS: A study of surface-association curves of E. coli and B. subtilis revealed that surface adhesion in biofilms was continuously constant as compared to their planktonic forms, thereby confirming the increased survival of bacteria in biofilms. Also, biofilms have shown high resistance towards the penicillin G, ampicillin and streptomycin as compared to their planktonic form. CONCLUSION: It is safely inferred that E. coli and B. subtilis, in their biofilms, become increasingly resistant to penicillin G, ampicillin and streptomycin.

3.
Clin Pediatr (Phila) ; : 99228241271938, 2024 Aug 14.
Article de Anglais | MEDLINE | ID: mdl-39143670

RÉSUMÉ

The aim of this study was to compare sequelae and acute kidney injury (AKI) occurrence among patients with necrotizing enterocolitis (NEC) after changing institutional guidelines replacing vancomycin with ampicillin for gram-positive coverage. This was a retrospective, single-center cohort analysis of patients from 2016-2020 (n = 73) with NEC at a surgical neonatal intensive care unit with a high community prevalence of methicillin-resistant Staphylococcus aureus (MRSA). Multivariate logistic regression was utilized to assess associations. Twenty-five (34%) patients had at least 1 sequela related to NEC. Ampicillin containing regimens were not associated with any sequelae type or AKI. Postmenstrual age < 29 weeks at diagnosis ([OR] 5.8 [1.2-28.8], P = .03; and receipt of vasopressors [OR] 3.3 [1.1-10.2], P = .04) were independently associated with sequalae. Stage III NEC was independently associated with AKI, OR 10.6 (2-55.6), P = .005. In conclusion, ampicillin-containing regimens are effective for NEC management at our institution despite a high prevalence of MRSA.

4.
Antibiotics (Basel) ; 13(8)2024 Jul 25.
Article de Anglais | MEDLINE | ID: mdl-39199996

RÉSUMÉ

In Japan, only ampicillin/cloxacillin (ABPC/MCIPC) is available as an anti-staphylococcal penicillin-based treatment for Staphylococcus aureus bacteremia. However, the incidence of adverse events associated with double beta-lactam administration remains unknown. Therefore, we investigated the adverse events of double beta-lactam administration in patients with bacteremia. Adult patients (≥18 years) with bacteremia treated with ABPC, ABPC + ceftriaxone (CTRX), or ABPC/MCIPC were retrospectively analyzed. The primary outcome of this study was the incidence of adverse events such as acute kidney injury, liver dysfunction, and myelosuppression. Chi-square tests and t-tests were used for bivariate analysis. Propensity score (PS) matching was conducted to adjust for confounding factors. We included 277 ABPC-, 57 ABPC + CTRX-, and 43 ABPC/MCIPC-treated patients. Significant differences were noted in age, number of male patients, proportion of patients with qSOFA score ≥2, incidence of chronic kidney disease, treatment duration, mechanical ventilation use, vasopressor use, and proportion of patients with acute kidney injury (AKI) KDIGO grade ≥2. Further, a significant difference was observed between ABPC and ABPC/MCIPC, with a hazard ratio of 1.83 in AKI. In the PS-matched cohort, AKI incidence associated with ABPC/MCIPC was significantly higher than that associated with ABPC. ABPC + CTRX may be safe, whereas ABPC/MCIPC presents a higher risk of AKI and may not be suitable.

5.
Article de Anglais | MEDLINE | ID: mdl-39089437

RÉSUMÉ

BACKGROUND: Maximal skin testing (ST) nonirritant concentrations (NICs) are consistent for penicillin and aminopenicillin among guidelines. However, there is variability among guidelines for maximal ST NICs of cephalosporins. OBJECTIVE: To determine maximal immediate and delayed ST NICs of 15 ß-lactams in ß-lactam-tolerant and ß-lactam-naïve participants. METHODS: We performed a single-center, nonrandomized prospective study between September 2019 and January 2022 in adult participants. Participants received skin prick testing (SPT) and intradermal test (IDT) injections at 6 increasing concentrations of 1 or more ß-lactams. A concentration was considered irritant when more than 5% of participants had a positive test. A positive test was defined as a wheal ≥3 mm compared with negative control accompanied by a ≥5 mm flare for SPT/IDT and induration ≥5 mm with associated erythema at 48 hours for delayed readings (dIDT). Sensitivity analyses using 3 alternative IDT positive criteria were conducted. RESULTS: A total of 747 participants with a median age of 64 (interquartile range: 54-72) years (52% male, 85% White, and 92% non-Hispanic) underwent 20,858 skin tests. All undiluted SPT concentrations were nonirritant. We found the following maximal IDT/dIDT NICs (mg/mL): ampicillin (41.6/125), ampicillin-sulbactam (93.8/187.5), aztreonam (6.3/25), cefazolin (55/165), cefepime (35/140), cefoxitin (45/90), ceftaroline (7.5/15), ceftriaxone (58.3/175), cefuroxime (55/110), ertapenem (16.6/50), imipenem-cilastin (6.3/25), meropenem (8.3/25), nafcillin (31.3/62.5), oxacillin (20.9/83.5), and piperacillin-tazobactam (112.5/225). dIDTs were almost all completely nonirritant close to or at undiluted concentrations. There were no differences when we applied 3 IDT positivity criteria to our raw data. CONCLUSIONS: Our results suggest that SPTs with undiluted stock ß-lactam antibiotic concentrations are nonirritant. Compared with previously published nonirritant concentrations, we propose a 2- to 50-fold increase to the maximal IDT and dIDT NICs of 15 ß-lactam antibiotics. When performing dIDTs, a higher concentration should be used rather than the same IDT concentration.

6.
Environ Technol ; : 1-13, 2024 Aug 30.
Article de Anglais | MEDLINE | ID: mdl-39215485

RÉSUMÉ

As the problem of multi-resistant bacteria grows a better understanding of the spread of antibiotic resistance genes is of utmost importance for society. Wastewater treatment plants contain subinhibitory concentrations of antibiotics and are thought to be hotspots for antibiotic resistance gene propagation. Here we evaluate the influence of sub-minimum inhibitory concentrations of antibiotics on the spread of resistance genes within the bacterial community in activated sludge laboratory-scale sequencing batch reactors. The mixed communities were fed two different ampicillin concentrations (500 and 5000 µg/L) and the reactors were run and monitored for 30 days. During the experiment the ß-lactamase resistance gene blaCMY-2 was monitored via qPCR and DNA samples were taken to monitor the effect of ampicillin on the microbial community. The relative copy number of blaCMY-2 in the reactor fed with the sub-minimum inhibitory concentration of 500 µg/L ampicillin was spread out over a wider range of values than the control and 5000 µg/L ampicillin reactors indicating more variability of gene number in the 500 µg/L reactor. This result emphasises the problem of sub-minimum inhibitory concentrations of antibiotics in wastewater. High-throughput sequencing showed that continuous exposure to ampicillin caused a shift from a Bacteroidetes to Proteobacteria in the bacterial community. The combined use of qPCR and high-throughput sequencing showed that ampicillin stimulates the spread of resistance genes and leads to the propagation of microbial populations which are resistant to it.

7.
Biochem Biophys Res Commun ; 734: 150622, 2024 Aug 29.
Article de Anglais | MEDLINE | ID: mdl-39216410

RÉSUMÉ

Administration of coronavirus disease-2019 (COVID-19) vaccines with appropriate booster doses through painful injections under clinical supervision was challenging during the recent COVID-19 pandemic. As an alternative solution, we designed a safer, edible probiotic yogurt vaccine prototype (YoVac) that can be orally consumed by circumventing painful injections and clinical supervision. We hypothesized that YoVac prepared using Lactobacillus carrying an antigen coding gene (donor) can transfer the same to other bacteria (recipients) in the human gut microbiome (hgMb) through lateral gene transfer (LGT) for boosted antigen levels potentially triggering a robust immune response. In this study we confirmed the in vitro LGT efficiency of a plasmid (pRBD-Ampr) containing severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) spike protein-receptor binding domain (RBD) coding gene along with an ampicillin-resistance gene (selection marker) from the probiotic Lactobacillus (donor) cultured from homemade yogurt to E. coli and Helicobacter pylori (recipients). Both the donor and recipient bacteria not only exhibited ampicillin-resistance from pRBD-Ampr but also expressed RBD protein. Furthermore, Lactobacillus isolated from YoVac consistently showed the expression of RBD protein over a period of one month confirming the shelf life of our prototype stored at 4 °C. Taken together, our in vitro results provide a preliminary basis for the potential in vivo transfer of RBD coding gene from YoVac to other bacterial species in the hgMb through LGT and may potentially boost the vaccine dosage by delegating them.

8.
Life (Basel) ; 14(8)2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39202719

RÉSUMÉ

Haematococcus lacustris (Girod-Chantrans) Rostafinski (Chlorophyta) is the richest microalgal source of astaxanthin. Natural astaxanthin from H. lacustris has been widely studied and used for commercial production worldwide. In this study, we examined the effects of 11 antibiotics (dihydrostreptomycin sulphate, neomycin, chloramphenicol, penicillin, streptomycin, ampicillin, kanamycin, gentamycin, hygromycin B, tetracycline, and paromomycin) on the biomass dry weight, growth, and astaxanthin yield of H. lacustris using Jaworski's medium without a nitrogen source. Astaxanthin content in H. lacustris was improved in the presence of ampicillin (0.25 g/L, 0.5 g/L, 1 g/L), chloramphenicol (0.25 g/L), and penicillin (0.25 g/L, 0.5 g/L, 1 g/L) in comparison to the control on day 15. The greatest increase in astaxanthin content on day 15 (6.69-fold) was obtained with the addition of penicillin (0.5 g/L) in comparison to the control. Similarly, on day 15, the cell numbers were also the highest for the H. lacustris culture grown with the addition of penicillin (0.5 g/L).

9.
J Mol Recognit ; 37(5): e3100, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39014869

RÉSUMÉ

Metallo-ß-lactamases (MßLs) hydrolyze and inactivate ß-lactam antibiotics, are a pivotal mechanism conferring resistance against bacterial infections. SMB-1, a novel B3 subclass of MßLs from Serratia marcescens could deactivate almost all ß-lactam antibiotics including ampicillin (AMP), which has posed a serious threat to public health. To illuminate the mechanism of recognition and interaction between SMB-1 and AMP, various fluorescence spectroscopy techniques and molecular dynamics simulation were employed. The results of quenching spectroscopy unraveled that AMP could make SMB-1 fluorescence quenching that mechanism was the static quenching; the synchronous and three-dimensional fluorescence spectra validated that the microenvironment and conformation of SMB-1 were altered after interaction with AMP. The molecular dynamics results demonstrated that the whole AMP enters the binding pocket of SMB-1, even though with a relatively bulky R1 side chain. Loop1 and loop2 in SMB-1 undergo significant fluctuations, and α2 (71-73) and local α5 (186-188) were turned into random coils, promoting zinc ion exposure consistent with circular dichroism spectroscopy results. The binding between them was driven by a combination of enthalpy and entropy changes, which was dominated by electrostatic force in agreement with the fluorescence observations. The present study brings structural insights and solid foundations for the design of new substrates for ß-lactamases and the development of effective antibiotics that are resistant to superbugs.


Sujet(s)
Ampicilline , Simulation de dynamique moléculaire , Serratia marcescens , Spectrométrie de fluorescence , bêta-Lactamases , bêta-Lactamases/composition chimique , bêta-Lactamases/métabolisme , Ampicilline/composition chimique , Ampicilline/métabolisme , Ampicilline/pharmacologie , Serratia marcescens/enzymologie , Liaison aux protéines , Sites de fixation , Antibactériens/composition chimique , Antibactériens/pharmacologie , Antibactériens/métabolisme , Protéines bactériennes/composition chimique , Protéines bactériennes/métabolisme
10.
Int J Pharm ; 662: 124483, 2024 Sep 05.
Article de Anglais | MEDLINE | ID: mdl-39029636

RÉSUMÉ

Single and dual bioactive linear poly(ionic liquid)s (PIL) were synthesized for use as nanocarriers in drug delivery systems (DDS). These PILs were obtained through the (co)polymerization of the choline-based monomeric ionic liquids (MIL) with pharmaceutical anions possessing antibacterial properties, specifically [2-(methacryloyloxy)ethyl]trimethyl-ammonium with ampicillin and p-aminosalicylate (TMAMA/AMP and TMAMA/PAS). The copolymers exhibited varying chain lengths defined by a degree of polymerization (DPn = 122-370), and differing contents of ionic fraction and drugs (TMAMA 61-92 %, AMP 61-93 % and PAS 16-21 %). These parameters were adjustable by the monomer conversion (33-92 %) and the initial ratio of comonomers. In aqueous solution, the polymer particles reached nanosizes, i.e. 190-328 nm for AMP systems and 200-235 nm for AMP/PAS systems. In the release process, the pharmaceutical anions were released through exchange by phosphate anions in PBS at pH 7.4 at 37 °C. Depending on the copolymer composition the release of AMP was attained in 72-100 % (11.1-19.5 µg/mL) within 26 h by the single drug systems, while the dual drug systems released 61-100 % of AMP (14.8-24.7 µg/mL) and 82-100 % of PAS (3.1-4.8 µg/mL) within 72 h. The effectiveness in the drug delivery of the designed TMAMA polymers seems to be promising for future applications in antibiotic therapy and the combined therapy.


Sujet(s)
Ampicilline , Antibactériens , Vecteurs de médicaments , Libération de médicament , Liquides ioniques , Nanoparticules , Polymères , Ampicilline/composition chimique , Ampicilline/administration et posologie , Liquides ioniques/composition chimique , Antibactériens/administration et posologie , Antibactériens/composition chimique , Vecteurs de médicaments/composition chimique , Polymères/composition chimique , Nanoparticules/composition chimique , Acide aminosalicylique/composition chimique , Acide aminosalicylique/administration et posologie , Systèmes de délivrance de médicaments , Polymérisation
11.
Cureus ; 16(5): e61376, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38947678

RÉSUMÉ

A 50-year-old man presented with fever and a generalized rash, with chronic fatigue and lymphadenopathy for a year and a half. Initial tests ruled out lymphoproliferative disorders, showing reactive hyperplasia and cytomegalovirus. Symptoms worsened after ampicillin treatment, leading to suspected drug-induced hypersensitivity syndrome (DIHS). Upon admission, amoxicillin was discontinued, and prednisolone and antiviral treatment were initiated. The patient's condition improved with this therapy. A drug-induced lymphocyte stimulation test confirmed hypersensitivity to both ampicillin and allopurinol. This case illustrates the diagnostic challenge of chronic and acute DIHS because of the rare presentation. It underscores the need for high suspicion of DIHS in patients with chronic lymphadenopathy and fatigue, particularly with recent drug exposure. Effective management involves recognizing symptoms, withdrawing the offending drug, and using corticosteroids. Viral infections like cytomegalovirus can complicate DIHS diagnosis and treatment, necessitating a comprehensive approach. This case highlights the importance of considering DIHS in differential diagnoses and the complexities of managing it alongside co-infections in rural healthcare settings.

12.
Int J Med Microbiol ; 316: 151626, 2024 Jun 17.
Article de Anglais | MEDLINE | ID: mdl-38954914

RÉSUMÉ

BACKGROUND: Aminopenicillins are recommended agents for non-invasive Haemophilus influenzae infections. One of the mechanisms of resistance to ß-lactams is the alteration of the transpeptidase region of penicillin binding protein 3 (PBP3) which is caused by mutations in the ftsI gene. It was shown that exposure to beta-lactams has a stimulating effect on increase of prevalence of H. influenzae strains with the non-enzymatic mechanism of resistance. OBJECTIVES: The aim of our study was to compare the mutational potential of ampicillin and cefuroxime in H. influenzae strains, determination of minimum inhibitory concentration and the evolution of mutations over time, focusing on amino acid substitutions in PBP3. METHODS: 30 days of serial passaging of strains in liquid broth containing increasing concentrations of ampicillin or cefuroxime was followed by whole-genome sequencing. RESULTS: On average, cefuroxime increased the minimum inhibitory concentration more than ampicillin. The minimum inhibitory concentration was increased by a maximum of 32 fold. Substitutions in the PBP3 started to appear after 15 days of passaging. In PBP3, cefuroxime caused different substitutions than ampicillin. CONCLUSIONS: Our experiment observed differences in mutation selection by ampicillin and cefuroxime. Selection pressure of antibiotics in vitro generated substitutions that do not occur in clinical strains in the Czech Republic.

13.
Article de Anglais | MEDLINE | ID: mdl-38958001

RÉSUMÉ

Background: The optimal ampicillin-sulbactam dosing regimen for carbapenem-susceptible Acinetobacter baumannii isolates in critically ill trauma patients has not been clearly defined. One strategy to provide the adequate sulbactam dose includes high-dose continuous infusion. Case(s) Description: We present three cases of critically ill trauma patients with augmented renal clearance treated with high-dose ampicillin-sulbactam through an intravenous continuous infusion for ventilator-associated pneumonia. All A. baumannii isolates were susceptible to sulbactam with low minimum inhibitory concentrations. All achieved clinical cure at the end of therapy and no recurrent pneumonia was noted. No clinically substantial adverse effect attributable to ampicillin-sulbactam therapy occurred. Discussion: There is limited evidence to endorse high-dose, continuous infusion ampicillin-sulbactam for treatment of infections caused by carbapenem-susceptible A. baumannii. This report presents three critically ill trauma patients with augmented renal clearance that achieved positive clinical outcomes with higher doses of ampicillin-sulbactam administered through a continuous infusion.

14.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124872, 2024 Dec 15.
Article de Anglais | MEDLINE | ID: mdl-39067359

RÉSUMÉ

Ampicillin (AMP) is a ß-lactam antibiotic that can inhibit bacterial wall synthesis. The overuse and misuse of AMP makes it micropollutant that commonly found in food and various environmental media. In this work, a fluorescence polarization sensor was designed to sensitive detection of trace ampicillin based on click chemistry, using graphene oxide (GO) as a fluorescence polarization (FP) signal enhancement element. First, when ampicillin binds to its aptamer (apt), the adjacent alkyne and azide groups are separated, hindering the click-linking reaction. When Carboxyfluorescein (FAM) fluorophore-labeled probe (C-FAM) is added, its protruding 3-terminal FAM is recognized and cleaved by exonuclease I (EXO I), releasing fluorophores free that could not be adsorbed on GO, resulting in a lo0wer polarization signal. If there is no AMP in the system, aptamer probe is connected to its complementary chain ends by a click reaction. After C-FAM hybridizes with apt, the apt/P duplex is opened and the prominent single-stranded ends adsorb on the GO, leading a significantly enhanced FP signal. According to the relationship between the difference in FP values and the concentrations of AMP, the limit of detection of proposed method is as low as 80 pg/mL. This assay has a wide linear range plus excellent selectivity, and has been applied to detect AMP in milk and river water samples with satisfactory results, which demonstrates that the FP sensor has great potential for practical applications in food safety and environmental protection fields.


Sujet(s)
Ampicilline , Aptamères nucléotidiques , Chimie click , Polarisation de fluorescence , Graphite , Limite de détection , Ampicilline/analyse , Graphite/composition chimique , Aptamères nucléotidiques/composition chimique , Polarisation de fluorescence/méthodes , Animaux , Lait/composition chimique , Techniques de biocapteur/méthodes , Colorants fluorescents/composition chimique
15.
Eur J Clin Microbiol Infect Dis ; 43(9): 1711-1719, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38970691

RÉSUMÉ

To evaluate the in vitro activity of ampicillin-sulbactam and cefoperazone-sulbactam against A. baumannii using the broth disk elution testing, a total of 150 A. baumannii isolates were collected from across China between January 2019 and January 2021, including 51 carbapenem-susceptible and 99 carbapenem-resistant isolates. Broth disk elution (BDE) and the broth microdilution (BMD) method were performed for all strains. The concentration range of the BDE was 10/10 µg/mL, 20/20 µg/mL, and 30/30 µg/mL for ampicillin-sulbactam, and 37.5/15 µg/mL, 75/30 µg/mL, 112.5/45 µg/mL, and 150/60 µg/mL for cefoperazone-sulbactam, respectively. Compared with BMD, the BDE results of ampicillin-sulbactam and cefoperazone-sulbactam showed a categorical agreement of 83.3% (125/150) and 95.3% (143/150), with minor errors of 16.7% (25/150) and 4.7% (7/150), respectively. No major error or very major errors were detected. The sensitivity differences by BDE of carbapenem-resistant A. baumannii (CRAb) to different concentrations of ampicillin-sulbactam showed statistically significant (p < 0.017), while those to cefoperazone-sulbactam at 37.5/15 µg/mL, 75/30 µg/mL, and 112.5/45 µg/mL were significant (p < 0.008). However, no significant difference in sensitivity was observed between 112.5/45 µg/mL and 150/60 µg/mL (p > 0.008). In conclusion, the BDE is a reliable and convenient method to detect the in vitro activity of cefoperazone-sulbactam against A. baumannii, and the results could serve as a clinical reference value when deciding whether or not to use high-dose sulbactam for the treatment of A. baumannii infections.


Sujet(s)
Acinetobacter baumannii , Ampicilline , Antibactériens , Céfopérazone , Sulbactam , Acinetobacter baumannii/effets des médicaments et des substances chimiques , Sulbactam/pharmacologie , Céfopérazone/pharmacologie , Ampicilline/pharmacologie , Antibactériens/pharmacologie , Humains , Infections à Acinetobacter/microbiologie , Tests de sensibilité microbienne , Chine , Tests d'agents antimicrobiens par diffusion à partir de disques/méthodes
16.
Int J Nanomedicine ; 19: 5397-5418, 2024.
Article de Anglais | MEDLINE | ID: mdl-38863647

RÉSUMÉ

Background: The healing of burn wounds is a complicated physiological process that involves several stages, including haemostasis, inflammation, proliferation, and remodelling to rebuild the skin and subcutaneous tissue integrity. Recent advancements in nanomaterials, especially nanofibers, have opened a new way for efficient healing of wounds due to burning or other injuries. Methods: This study aims to develop and characterize collagen-decorated, bilayered electrospun nanofibrous mats composed of PVP and PVA loaded with Resveratrol (RSV) and Ampicillin (AMP) to accelerate burn wound healing and tissue repair. Results: Nanofibers with smooth surfaces and web-like structures with diameters ranging from 200 to 400 nm were successfully produced by electrospinning. These fibres exhibited excellent in vitro properties, including the ability to absorb wound exudates and undergo biodegradation over a two-week period. Additionally, these nanofibers demonstrated sustained and controlled release of encapsulated Resveratrol (RSV) and Ampicillin (AMP) through in vitro release studies. The zone of inhibition (ZOI) of PVP-PVA-RSV-AMP nanofibers against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) was found 31±0.09 mm and 12±0.03, respectively, which was significantly higher as compared to positive control. Similarly, the biofilm study confirmed the significant reduction in the formation of biofilms in nanofiber-treated group against both S. aureus and E. coli. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis proved the encapsulation of RSV and AMP successfully into nanofibers and their compatibility. Haemolysis assay (%) showed no significant haemolysis (less than 5%) in nanofiber-treated groups, confirmed their cytocompatibility with red blood cells (RBCs). Cell viability assay and cell adhesion on HaCaT cells showed increased cell proliferation, indicating its biocompatibility as well as non-toxic properties. Results of the in-vivo experiments on a burn wound model demonstrated potential burn wound healing in rats confirmed by H&E-stained images and also improved the collagen synthesis in nanofibers-treated groups evidenced by Masson-trichrome staining. The ELISA assay clearly indicated the efficient downregulation of TNF-alpha and IL-6 inflammatory biomarkers after treatment with nanofibers on day 10. Conclusion: The RSV and AMP-loaded nanofiber mats, developed in this study, expedite burn wound healing through their multifaceted approach.


Sujet(s)
Ampicilline , Brûlures , Collagène , Escherichia coli , Nanofibres , Poly(alcool vinylique) , Povidone , Resvératrol , Staphylococcus aureus , Cicatrisation de plaie , Resvératrol/pharmacologie , Resvératrol/composition chimique , Resvératrol/administration et posologie , Resvératrol/pharmacocinétique , Nanofibres/composition chimique , Brûlures/traitement médicamenteux , Cicatrisation de plaie/effets des médicaments et des substances chimiques , Animaux , Collagène/composition chimique , Povidone/composition chimique , Staphylococcus aureus/effets des médicaments et des substances chimiques , Poly(alcool vinylique)/composition chimique , Humains , Escherichia coli/effets des médicaments et des substances chimiques , Ampicilline/pharmacologie , Ampicilline/composition chimique , Ampicilline/pharmacocinétique , Ampicilline/administration et posologie , Antibactériens/pharmacologie , Antibactériens/composition chimique , Antibactériens/administration et posologie , Rats , Biofilms/effets des médicaments et des substances chimiques , Mâle
17.
Infect Drug Resist ; 17: 2329-2335, 2024.
Article de Anglais | MEDLINE | ID: mdl-38882654

RÉSUMÉ

The escalating incidence of infective endocarditis (IE) caused by aminoglycoside-resistant Enterococcus is a growing concern for clinicians. This issue is particularly pronounced in elderly patients, who face an elevated risk of renal damage during antibiotic treatment, thereby limiting available pharmacological options. Furthermore, elderly patients often present with multiple comorbidities, leading to heightened mortality rates. In this article, we present a case involving an elderly male patient who sought medical attention on two separate occasions due to inflammation of the lower extremities and lumbosacral pain. Subsequent diagnosis revealed infective endocarditis (IE) caused by high-level gentamicin-resistant Enterococcus faecalis through blood culture and echocardiography. The patient also experienced peripheral and cerebral arterial embolism, secondary spine infection, and subsequent heart failure, highlighting the severity of the clinical situation. Following an initial 10-day course of vancomycin and ceftriaxone therapy, the patient developed renal impairment, necessitating a switch to bactericidal therapy with ampicillin in combination with ceftriaxone. Additionally, aortic valve replacement was performed during this period. Ultimately, the patient achieved clinical remission. This case underscores the critical importance of prompt and accurate diagnosis, appropriate antibiotic selection, and timely surgical intervention in enhancing the prognosis of elderly patients with IE.

18.
Heliyon ; 10(10): e31617, 2024 May 30.
Article de Anglais | MEDLINE | ID: mdl-38826735

RÉSUMÉ

The detection of ampicillin plays a crucial role in managing and monitoring its usage and resistance. This study introduces a simple and effective biosensor for ampicillin detection, utilizing the unique absorbance features of Mn-doped ZnS capped by chitosan micromaterials in conjunction with ß-lactamase activity. The biosensors can detect ampicillin concentrations from 13.1 to 72.2 µM, with a minimum detection limit of 2.93 µM for sensors based on 300 mg/L of the sensing material. In addition, these sensors show high specificity for ampicillin over other antibiotics such as penicillin, tetracycline, amoxicillin, cephalexin, and a non-antibiotic-glucose. This specificity is demonstrated by an enhancing effect when beta-lactamase is used, as opposed to a quenching effect observed at 340 nm in the absorbance spectrum when no beta-lactamase is present. This research highlights the potential of affordable chitosan-capped Mn-doped ZnS micromaterials for detecting ampicillin through simple absorbance measurements, which could improve the monitoring of antibiotics in both clinical and environmental settings.

19.
Braz J Microbiol ; 2024 Jun 04.
Article de Anglais | MEDLINE | ID: mdl-38831174

RÉSUMÉ

Multidrug-resistant pathogenic vibrios are a crisis of concern as they cause multiple illnesses, including gastroenteritis in humans and acute hepatopancreatic necrosis in aquaculture. In the current study, we investigated the prevalence of the beta-lactamase gene CTX-M-group 1 in Vibrio spp. (Vibrio cholerae and Vibrio parahaemolyticus) from the water and sediment of urban tropical mangrove ecosystems of Kerala, southwest India. A total of 120 isolates of Vibrio spp. were tested for antibiotic susceptibility to 14 antibiotics. In water, ampicillin resistance was very high in isolates of V. cholerae (94.1%, n = 17) and V. parahaemolyticus (89.1%, n = 46). 26.9% of V. parahaemolyticus and 14.2% of V. cholerae harbored the CTX-M-group 1 gene in water samples. Compared to V. cholerae, the CTX-M-group 1 gene was exclusively hosted by V. parahaemolyticus (49%) in sediment samples. A significant difference in the prevalence of the CTX-M-group 1 gene was observed among Vibrio spp. in both water and sediment samples (p < 0.05). The results revealed the presence of multidrug-resistant and beta-lactamase harboring Vibrio spp. in mangrove ecosystems, which may have evolved as a consequence of the misuse and abuse of broad-spectrum antibiotics as prophylaxis in human health care and aquaculture.

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