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1.
Food Sci Nutr ; 12(4): 2818-2832, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628214

RESUMO

This is a comparative study to evaluate the effectiveness of six pomegranate peel extracts (PPEs) as antibacterial and antiproliferative agents. The Six PPEs were prepared using four solvent systems and each filtrate was concentrated to a gummy material to be used in the evaluation. The well-diffusion method was used to evaluate their antimicrobial activity against bacteria typically associated with food spoilage: Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus aureus, and three Bacillus species. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTT) was used to evaluate the cytotoxicity against colorectal carcinoma cells (HCT116), prostate adenocarcinoma (PC3), ovarian cancer cells (SKOV-3), and fibroblasts (MRC-5). The antioxidant evaluation was done using the 2,2-diphenyl-1-picrylhydrazyl-hydrate (DPPH) assay. The pH of the water-containing extracts was acidic and almost the same over 6 weeks. The six PPEs inhibited the bacterial growth in a comparable level to standard antibiotics. The effectiveness of each extract was dependent on the bacterial strain, and the Listeria showed a remarkable inhibition when exposed to the aqueous extract prepared at room temperature (RT). The aqueous (RT) and methanol PPEs had a significant antioxidant scavenging capability and a remarkable cytotoxic activity against the PC3 with half maximal inhibitory concentration (IC50) of 0.1 µg/mL. The boiled aqueous extract exhibited antiproliferative activity against HCT116 with an IC50 of 21.45 µg/mL. The effect on SKOV-3 and fibroblasts was insignificant. With the exception of butanol, the antioxidant screening shows an inverse correlation between the polarity of the extraction solvent and the IC50 exhibited by the PPEs. The variation in the effectiveness of PPEs is suggested to be due to variable soluble bioactive compounds that may interact differently with different cells, though water-containing extracts are promising antibacterial agents. The findings clearly show that pomegranate peel possessed the potential to be an eco-friendly novel source for natural compounds that can be implemented in the food industry as a natural antimicrobial and natural food additive to prevent foodborne illnesses.

2.
J Food Prot ; 87(6): 100271, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38561027

RESUMO

Cooked, uncured meat products packaged under reduced oxygen packaging conditions require the control of anaerobic and facultative anaerobic pathogens if they are held at temperatures greater than 3°C at retail or consumer level. The objective of this study was to determine the inhibition of Listeria monocytogenes and Clostridium botulinum in cooked, uncured shredded turkey and pork formulated with synthetic or clean-label antimicrobials. Treatments of shredded meat products were prepared with or without antimicrobials using turkey thigh or breast that were cooked to 85°C, shredded, and chilled before inoculation with the target pathogen. L. monocytogenes inoculated samples were stored at 7.2°C, whereas C. botulinum samples were stored at 12.8°C; triplicate samples were assayed every 2 weeks. In the first set of experiments, L. monocytogenes populations increased 2 to 3 logs within 2 weeks of storage at 7.2°C in both meat control treatments without antimicrobials and in pork with 4% lactate-diacetate blend (LD). A 1-log increase was observed in turkey with 4% LD and Pork with 2% cultured dextrose-vinegar-rosemary (CDVR) under the same storage conditions; a 1-log increase was observed in turkey with CDVR at 4 weeks. The second set of experiments tested the effect of pH reduction (to less than 5.5 by the addition of 0.5% citric acid) in combination with 2% CDVR when added to the brine precook or postcook during shredding. Populations of L. monocytogenes increased 4-log within 2 and 4 weeks at 7.2°C for the control turkey and pork formulations, respectively. No growth was observed in 12 weeks for any antimicrobial CDVR-CA treatments regardless of how antimicrobial was added. Similarly, botulinum toxin was detected in both control treatments at week 2 at 12.8°C, but no toxicity was observed in either antimicrobial treatment through 12 weeks. These data suggest that a combination of 2% cultured dextrose-vinegar-rosemary extract plus 0.5% citric acid to reduce pH inhibits the growth of L. monocytogenes and toxin production of C. botulinum in uncured shredded turkey and pork products stored under mild temperature abuse conditions for up to 12 weeks in reduced oxygen packaging.

3.
Indian J Dermatol ; 69(1): 106, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572036

RESUMO

Background: Adverse drug reactions (ADRs) are major problems in the drug therapy. Cutaneous adverse drug reactions (CADRs) are the most common ADRs. The pattern of CADRs differs among various drugs. Aims: To record various morphological patterns of CADRs and their causal relationships among patients attending in a tertiary care centre. Materials and Methods: An observational, cross-sectional, clinical study was conducted for a duration of one and a half years in a tertiary care centre in eastern India. Patients presenting with suspected CADRs were included if drug identity could be ascertained. Clinical profiling and drug history were recorded, and causality assessment was carried out as per the Naranjo scale. Result: The commonest CADR in our study was fixed drug eruption (FDE) 48.61%, followed by SJS-TEN spectrum 16.66%, maculopapular rash 11.11% and so on. Severe cutaneous adverse drug reactions (SCARs) such as SJS, TEN, SJS-TEN Overlap, AGEP and DRESS accounted for 18 cases (25%). The most common culprit drugs were antimicrobials (54.16%), followed by nonsteroidal anti-inflammatory drugs (15.27%) and anticonvulsants (12.5%). Most of the CADRs were in probable category. Conclusion: The pattern of CADRs and the drugs causing them in our study population are similar to some previous studies but somewhat different from most of the previous Indian studies. The incidence of SCARs was significantly higher than in previous other studies in India and abroad.

4.
Front Microbiol ; 15: 1342887, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38591029

RESUMO

Baby chicks administered a fecal transplant from adult chickens are resistant to Salmonella colonization by competitive exclusion. A two-pronged approach was used to investigate the mechanism of this process. First, Salmonella response to an exclusive (Salmonella competitive exclusion product, Aviguard®) or permissive microbial community (chicken cecal contents from colonized birds containing 7.85 Log10Salmonella genomes/gram) was assessed ex vivo using a S. typhimurium reporter strain with fluorescent YFP and CFP gene fusions to rrn and hilA operon, respectively. Second, cecal transcriptome analysis was used to assess the cecal communities' response to Salmonella in chickens with low (≤5.85 Log10 genomes/g) or high (≥6.00 Log10 genomes/g) Salmonella colonization. The ex vivo experiment revealed a reduction in Salmonella growth and hilA expression following co-culture with the exclusive community. The exclusive community also repressed Salmonella's SPI-1 virulence genes and LPS modification, while the anti-virulence/inflammatory gene avrA was upregulated. Salmonella transcriptome analysis revealed significant metabolic disparities in Salmonella grown with the two different communities. Propanediol utilization and vitamin B12 synthesis were central to Salmonella metabolism co-cultured with either community, and mutations in propanediol and vitamin B12 metabolism altered Salmonella growth in the exclusive community. There were significant differences in the cecal community's stress response to Salmonella colonization. Cecal community transcripts indicated that antimicrobials were central to the type of stress response detected in the low Salmonella abundance community, suggesting antagonism involved in Salmonella exclusion. This study indicates complex community interactions that modulate Salmonella metabolism and pathogenic behavior and reduce growth through antagonism may be key to exclusion.

5.
Am J Vet Res ; : 1-6, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38593824

RESUMO

OBJECTIVE: To evaluate if a difference in synovial amikacin concentrations exists in the radiocarpal joint (RCJ) following different durations of instillation of an IV regional limb perfusion (IVRLP) perfusate. ANIMALS: 7 healthy horses. METHODS: Horses received 2 IVRLPs with 2 g amikacin diluted to 60 mL with 0.9% NaCl via the cephalic vein in a crossover study design with a wash-out period between procedures. Instillation of the perfusate was administered over a 1-minute (technique 1) and 5-minute (technique 5) period. Concentrations of amikacin within the RCJ were measured at time (T) 5, 10, 15, 20, 25, and 30 minutes after instillation of the perfusate. Systemic concentrations of amikacin were measured at T0, 5, 10, 15, 20, 25, 29 minutes, and 1 minute after tourniquet removal (T31). Amikacin concentrations were determined by fluorescence polarization immunoassay. RESULTS: The median maximum concentration (CMAX) of amikacin within the RCJ for technique 1 was 338.4 µg/mL (range, 60 to 4,925 µg/mL), while the median CMAX for technique 5 was higher at 694.8 µg/mL (range, 169.2 to 3,410 µg/mL; P = .398). There was a higher amikacin blood concentration over time for technique 1 compared to technique 5 (P = .004). CLINICAL RELEVANCE: Administration of perfusate at different rates did not significantly affect synovial concentration of amikacin within the RCJ when performing IVRLP. However, increased systemic leakage was noted when the perfusate was administered over 1 minute, which might affect synovial concentrations in a larger group of horses.

6.
Microb Drug Resist ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579162

RESUMO

Antimicrobial resistance is a global public health emergency. The World Health Organization recently highlighted the growing number of new sexually transmitted infections such as gonorrhea, syphilis, and Chlamydia, which are resistant to common antibiotics. The phenomenon is also on the rise due to increasing intercontinental travel. Emerging antibiotic-resistant strains of gonorrhea are particularly associated with international spread from Southeast Asian travelers. Infection with Neisseria gonorrhoeae can cause a wide spectrum of associated diseases such as dermatitis, arthritis and septic arthritis, and pelvic inflammatory disease, and can even lead to serious health consequences for the individual. Natural infection confers no immunity, and vaccination is not available currently, although in several countries, it has been reported that the antimeningococcal vaccine may protect against gonorrhea. Implementing all necessary preventive measures is crucial, as well as appropriate and timely diagnostic methods and effective antimicrobial therapeutic treatments in the correct modalities to avoid the increase of forms of gonorrhea that are resistant to common antibiotics and difficult to eradicate.

7.
Biomaterials ; 308: 122576, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38640785

RESUMO

Biomaterial-associated infection (BAI) is considered a unique infection due to the presence of a biomaterial yielding frustrated immune-cells, ineffective in clearing local micro-organisms. The involvement of surface-adherent/surface-adapted micro-organisms in BAI, logically points to biomaterial surface-modifications for BAI-control. Biomaterial surface-modification is most suitable for prevention before adhering bacteria have grown into a mature biofilm, while BAI-treatment is virtually impossible through surface-modification. Hundreds of different surface-modifications have been proposed for BAI-control but few have passed clinical trials due to the statistical near-impossibility of benefit-demonstration. Yet, no biomaterial surface-modification forwarded, is clinically embraced. Collectively, this leads us to conclude that surface-modification is a dead-end road. Accepting that BAI is, like most human infections, due to surface-adherent biofilms (though not always to a foreign material), and regarding BAI as a common infection, opens a more-generally-applicable and therewith easier-to-validate road. Pre-clinical models have shown that stimuli-responsive nano-antimicrobials and antibiotic-loaded nanocarriers exhibit prolonged blood-circulation times and can respond to a biofilm's micro-environment to penetrate and accumulate within biofilms, prompt ROS-generation and synergistic killing with antibiotics of antibiotic-resistant pathogens without inducing further antimicrobial-resistance. Moreover, they can boost frustrated immune-cells around a biomaterial reducing the importance of this unique BAI-feature. Time to start exploring the nano-road for BAI-control.

8.
Food Microbiol ; 121: 104517, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637079

RESUMO

Food preservatives are crucial in controlling microbial growth in processed foods to maintain food safety. Bacterial biofilms pose a threat in the food chain by facilitating persistence on a range of surfaces and food products. Cells in a biofilm are often highly tolerant of antimicrobials and can evolve in response to antimicrobial exposure. Little is known about the efficacy of preservatives against biofilms and their potential impact on the evolution of antimicrobial resistance. In this study we investigated how Salmonella enterica serovar Typhimurium responded to subinhibitory concentrations of four food preservatives (sodium chloride, potassium chloride, sodium nitrite or sodium lactate) when grown planktonically and in biofilms. We found that each preservative exerted a unique selective pressure on S. Typhimurium populations. There was a trade-off between biofilm formation and growth in the presence of three of the four preservatives, where prolonged preservative exposure resulted in reduced biofilm biomass and matrix production over time. All three preservatives selected for mutations in global stress response regulators rpoS and crp. There was no evidence for any selection of cross-resistance to antibiotics after preservative exposure. In conclusion, we showed that preservatives affect biofilm formation and bacterial growth in a compound specific manner. We showed trade-offs between biofilm formation and preservative tolerance, but no antibiotic cross-tolerance. This indicates that bacterial adaptation to continuous preservative exposure, is unlikely to affect food safety or contribute to antibiotic resistance.


Assuntos
Anti-Infecciosos , Salmonella typhimurium , Conservantes de Alimentos/farmacologia , Biofilmes , Antibacterianos/farmacologia , Bactérias
9.
Open Vet J ; 14(1): 553-563, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38633170

RESUMO

Background: Bacterial infections causing digestive problems are among the most serious threats to Egypt's duck industry, owing to their effects on feed utilization and body weight gain. Aim: As a result, the goal of this study was to identify bacterial pathogens causing enteritis in ducks as well as testing their antimicrobials resistance capabilities. Methods: Forty-two duck flocks from different localities at four Egyptian Governorates (El-Sharkia, El-Gharbia, El-Dakahlia, and El-Qaliobia) have been subjected to clinical and postmortem examination as well as bacterial isolation and identification. The liver samples have been collected aseptically from freshly euthanized ducks for bacterial isolation followed by identification using conventional biochemical tests, VITEK 2 system, and confirmatory polymerase chain reaction (PCR) for detection of the uid A gene (beta-glucuronidase enzyme) of Escherichia coli. In addition, antimicrobial sensitivity testing for the isolates against different antimicrobials by the VITEK 2 system was used. Results: Forty-six positive bacterial isolates were identified using conventional methods and the VITEK 2 system including Staphylococcus spp. (52.17%), E. coli (41.30%), and 2.17% for each of Enterococcus casseli lavus, Salmonella enterica subspecies arizonae, and Enterobacter cloacae. PCR was positive for E. coli uid A gene at 556 bp. The antibiogram patterns of isolated pathogens from naturally infected ducks in our work demonstrated 87% multidrug resistance with varying results against different antimicrobial drugs tested. Such findings supported the fact of the upgrading multidrug resistance of Staphylococci and Enterobacteriacae. Conclusion: The most prevalent bacterial pathogens associated with duck enteritis were Staphylococcus spp. and E. coli with the first report of S. enterica subspecies arizonae causing duck enteritis in Egypt.


Assuntos
Salmonella enterica , Animais , Salmonella arizonae , Patos , Egito , Escherichia coli , Antibacterianos/farmacologia , Staphylococcus , Resistência a Múltiplos Medicamentos
10.
Animals (Basel) ; 14(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612326

RESUMO

Herbal extracts have been widely evaluated in poultry production for their beneficial effects and potential substitute for antibiotics, which contribute to AMR and risks to human health through the consumption of infected meat. Salmonellosis is a systemic infection caused by Salmonella, an intracellular bacterium with the ability to cause systemic infections with significant implications for both the health and safety of farmers and consumers. The excessive use of antibiotics has escalated the incidence of antibiotic resistance bacteria in the poultry and livestock industry, highlighting the urgent need for alternatives especially in meat-type poultry. Both in vivo usage and in vitro studies of bioactive compounds from herbal extracts have demonstrated the effective antimicrobial activities against pathogenic bacteria, showing promise in managing Salmonella infections and enhancing poultry performance. Phytobiotic feed additives have shown promising results in improving poultry output due to their pharmacological properties, such as stimulating consumption, and enhancing antioxidant properties and preventing the increasing antimicrobial resistance threats. Despite potential for synergistic effects from plant-derived compounds, a further investigation into is essential to fully understand their role and mechanisms of action, for developing effective delivery systems, and for assessing environmental sustainability in controlling Salmonella in poultry production.

11.
Vet Anim Sci ; 23: 100342, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38434520

RESUMO

This field trial was conducted to evaluate two antibiotics at a close-up period in curing the existing IMI and to prevent new clinical and subclinical Intramammary infection (IMI). Two hundred and twelve Holstein cows were assigned to one of three treatment groups: TYLO, MARB and CONT. Cows in TYLO group received 10 mg/kg Tylosin for three days at the close-up period (21 days before calving), cows in MARB group received single SC injection of 8 mg/kg SC marbofloxacin at the close-up period and cows in CONT group remained untreated. Milk samples were collected for somatic cell count, microbial culture and Total oxidant/antioxidant capacity before drying-off, and 3 and 7days post calving. Antimicrobial susceptibility test and RAPT-PCR were performed on S.aureus isolates. No significant differences were detected in total cure rate within the groups, but S. aureus cure rates in TYLO and MARB were significantly higher than in CONT (74 and 73.5 % Vs 58.1 %). No significant differences in total new IMI were observed. Furthermore, the rate of new S. aureus IMI was higher in both treatment groups than in CONT group. Clinical mastitis rate in TYLO (3.8 %) and MARB (5.8 %) was significantly lower than CONT (11.3 %). Paired S. aureus isolates from dry-off and post-calving have been clustered into 9 different RAPD types (A-I). 8 paired strains collected at dry-off were identical to those at post-calving,and 35 strains had more than 60 % dissimilarity. Administration of Tylosin or Marbofloxacin is not useful in all cases;however, they have the potential to reduce the incidence of post-calving clinical mastitis and improve S.aureus cure rate if used selectively.

13.
Molecules ; 29(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474550

RESUMO

The global antibiotic resistance crisis has drawn attention to the development of treatment methods less prone to inducing drug resistance, such as antimicrobial photodynamic therapy (aPDT). However, there is an increasing demand for new photosensitizers capable of efficiently absorbing in the near-infrared (NIR) region, enabling antibacterial treatment in deeper sites. Additionally, advanced strategies need to be developed to avert drug resistance stemming from prolonged exposure. Herein, we have designed a conjugated oligoelectrolyte, namely TTQAd, with a donor-acceptor-donor (D-A-D) backbone, enabling the generation of reactive oxygen species (ROS) under NIR light irradiation, and cationic adamantaneammonium groups on the side chains, enabling the host-guest interaction with curcubit[7]uril (CB7). Due to the amphiphilic nature of TTQAd, it could spontaneously form nanoassemblies in aqueous solution. Upon CB7 treatment, the positive charge of the cationic adamantaneammonium group was largely shielded by CB7, leading to a further aggregation of the nanoassemblies and a reduced antibacterial efficacy of TTQAd. Subsequent treatment with competitor guests enables the release of TTQAd and restores its antibacterial effect. The reversible supramolecular switch for regulating the antibacterial effect offers the potential for the controlled release of active photosensitizers, thereby showing promise in preventing the emergence of drug-resistant bacteria.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/química , Sistemas de Liberação de Medicamentos , Resistência Microbiana a Medicamentos , Antibacterianos/farmacologia
14.
Front Microbiol ; 15: 1328923, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38516011

RESUMO

We present a novel optical nanomotion-based rapid antibiotic and antifungal susceptibility test. The technique consisted of studying the effects of antibiotics or antifungals on the nanometric scale displacements of bacteria or yeasts to assess their sensitivity or resistance to drugs. The technique relies on a traditional optical microscope, a video camera, and custom-made image analysis software. It provides reliable results in a time frame of 2-4 h and can be applied to motile, non-motile, fast, and slowly growing microorganisms. Due to its extreme simplicity and low cost, the technique can be easily implemented in laboratories and medical centers in developing countries.

15.
Pharmaceuticals (Basel) ; 17(3)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38543169

RESUMO

Antimicrobial resistance is a major global health issue. Metallo-ß-lactamases (MBL), in particular, are problematic because they can inactivate all classes of ß-lactams except aztreonam. Unfortunately, the latter may be simultaneously inactivated by serine ß-lactamases. The most dangerous known MBL is New Delhi Metallo-ß-lactamase (NDM). This study aimed to test the in vitro susceptibility to aztreonam in combination with novel ß-lactamase inhibitors (avibactam, relebactam, and vaborbactam) in clinical strains of Enterobacterales NDM which is resistant to aztreonam. We investigated 21 NDM isolates-including Klebsiella pneumoniae, Escherichia coli, and Citrobacter freundii-which are simultaneously resistant to aztreonam, ceftazidime/avibactam, imipenem/relebactam, and meropenem/vaborbactam. MICs for aztreonam combinations with novel inhibitors were determined using the gradient strip superposition method. The most effective combination was aztreonam/avibactam, active in 80.95% strains, while combinations with relebactam and vaborbactam were effective in 61.90% and 47.62%, respectively. In three studied strains, none of the studied inhibitors restored aztreonam susceptibility. Aztreonam/avibactam has the most significant antimicrobial potential for NDM isolates. However, combinations with other inhibitors should not be rejected in advance because we identified strain susceptible only to tested combinations with inhibitors other than avibactam. Standardization committees should, as soon as possible, develop official methodology for antimicrobial susceptibility testing for aztreonam with ß-lactamase inhibitors.

16.
Microorganisms ; 12(3)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38543527

RESUMO

This study aimed to evaluate the antibacterial, leishmanicidal, and cytotoxic potential of metabolites produced by bacteria isolated from rhizosphere soil samples. The bacterium was identified by genome sequencing as Streptomyces kronopolitis. A preliminary screening was carried out for the antimicrobial activity of S. kronopolitis, demonstrating activity against Staphylococcus aureus ATCC 6538, Corynebacterium diphtheriae ATCC 27010, C. diphtheriae ATCC 27012, and Mycobacterium abscessus, with inhibition halos of sizes 25, 36, 29, and 33 mm, respectively. To obtain secondary metabolites, the bacteria were subjected to submerged fermentation, and the metabolites were extracted using the liquid-liquid method with ethyl acetate. There was a similar MIC for M. abscessus and the two strains of C. diphtherium, reaching a concentration of 12.5 µg/mL, while that of S. aureus was 0.048 µg/mL. Assays for leishmanicidal activity and cytotoxicity against HEp-2 cells and red blood cells were performed. The metabolite showed an IC50 of 9.0 ± 0.9 µg/mL and CC50 of 221.2 ± 7.0 µg/mL. This metabolite does not have hemolytic activity and is more selective for parasites than for mammalian cells, with a selectivity index of 24.6. Thus, the studied metabolite may be a strong candidate for the development of less toxic drugs to treat diseases caused by pathogens.

17.
Pathogens ; 13(3)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38535603

RESUMO

Essential oils are liquids containing non-toxic compounds that are unfavorable to the growth of microorganisms. They are sold globally at affordable or very high prices, depending on the availability and type of plant, the scale of production, the extraction method, costs associated with logistics and electricity consumption, among other variables. Each year, the quantity of research dedicated to the antimicrobial potential of essential oils in poultry farming is expanding. Researchers consensually relay that this increase is due to the growing resistance of microorganisms to traditional antimicrobials and concerns about the toxicity of these products. This review proposes an analysis of the antimicrobial feasibility of using essential oils to address microbial challenges in poultry farms, aiming to ensure the production and supply of microbiologically safe hatching eggs. Based on the findings in the literature, in addition to following other necessary precautions in the daily routines of poultry farming practices, developing an antimicrobial control program with essential oils that integrates poultry facilities, poultry and hatching eggs, adapted to the particularities of each context seems to be extremely effective.

18.
Lett Appl Microbiol ; 77(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38533656

RESUMO

Silver compounds are used in wound dressings to reduce bioburden. Where infection is not rapidly resolved, bacteria may be exposed to sub-therapeutic concentrations of antimicrobials over prolonged periods of time. In this study, a panel of chronic wound bacteria, Pseudomonas aeruginosa (two strains), Staphylococcus aureus, and Escherichia coli, were exposed to silver nitrate on agar. Phenotypic characterization was achieved using broth microdilution sensitivity testing, a crystal violet biofilm assay, and a wax moth pathogenesis model. Repeated exposure to ionic silver did not result in planktonic phenotypic silver resistance in any of the test panels, although S. aureus demonstrated reversible increases in minimum bactericidal concentration. An ulcer-derived P. aeruginosa exhibited marked reductions in biofilm eradication concentration as well as significantly increased biofilm formation and wax moth killing when compared to the same progenitor. These changes were reversible, trending towards baseline measurements following 10 passages on silver-free media. Changes in virulence and biofilm formation in the other test bacteria were generally limited. In summary, phenotypic adaptation following exposure to ionic silver was manifested other than through changes in planktonic susceptibility. Significant changes in pseudomonas biofilm formation and sensitivity could have implications for wound care regimes and therefore warrant further investigation.


Assuntos
Anti-Infecciosos , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Anti-Infecciosos/farmacologia , Bactérias , Bandagens , Biofilmes , Pseudomonas aeruginosa , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
19.
Infection ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478255

RESUMO

PURPOSE: Outpatient parenteral antimicrobial therapy (OPAT) offers several key advantages, including enhanced patient quality of life, reduced healthcare costs, and a potential reduction of nosocomial infections. It is acknowledged for its safety and effectiveness. This study provides the first systematic clinical data for Germany, where OPAT has not yet been widely adopted. The aim is to establish a foundational reference point for further research and integration of OPAT into the German healthcare system. METHODS: This prospective observational study descriptively analyses data obtained from a cohort of patients receiving OPAT. Both in- and outpatients from all medical specialties could be recruited. Patients administered the anti-infective medications themselves at home using elastomeric pumps. RESULTS: 77 patients received OPAT, with a median duration of 15 days and saving 1782 inpatient days. The most frequently treated entities were orthopaedic infections (n = 20, 26%), S. aureus bloodstream infection (n = 16, 21%) and infectious endocarditis (n = 11, 14%). The most frequently applied drugs were flucloxacillin (n = 18, 23%), penicillin G (n = 13, 17%) and ceftriaxone (n = 10; 13%). Only 5% of patients (n = 4) reported to have missed more than one outpatient dose (max. 3 per patient). Only one catheter-related adverse event required medical intervention, and there were no catheter-related infections. CONCLUSION: The study demonstrates that OPAT can be safely conducted in Germany. In preparation for its broader implementation, crucial next steps include creating medical guidelines, fostering interdisciplinary and inter-sectoral communication, as well as creating financial and structural regulations that facilitate and encourage the adoption of OPAT. TRIAL REGISTRATION NUMBER: NCT04002453.

20.
Foods ; 13(5)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38472808

RESUMO

Sea fennel is a halophytic plant rich in valuable nutritional components and is characterized by pleasant organoleptic properties. While its essential oils (EOs) are well investigated, there are no reports on the volatiles from their corresponding hydrolates, which are the main by-products of EO isolation, as well as on their biological activity. Therefore, the composition and biological activities of EOs and corresponding hydrolates of sea fennel from Atlantic (French, FRA) and Mediterranean (Croatian, CRO) ecotypes were investigated and compared. The EO from the CRO sample was characterized by an abundance of sabinene and limonene, while that from the FRA ecotype was rich in dillapiol and carvacryl methyl ether. The CRO hydrolate was rich in terpinen-4-ol and 10-(acetylmethyl)-3-carene, while dillapiol, thymyl methyl ether and γ-terpinene were the main compounds in the FRA sea fennel hydrolate. The biological activities of the EOs and hydrolates were evaluated for their antioxidant (with DPPH, NO, FRAP and ORAC bioassays), antimicrobial (against some Gram+ and Gram- spoilage bacteria) and antiageing (tyrosinase, elastase and collagenase inhibition) activities. Both EOs showed low reducing powers and antiradical activities while the ability of both hydrolates to quench NO was slightly higher (35-39% if inhibition). The FRA EO showed low activity against Staphylococcus aureus (8 mm), while CRO moderately inhibited the growth of P. aeruginosa (8 mm), but strongly inhibited the other two bacterial strains. While the French EO showed no antityrosinase and anticollagenase activity, the Croatian oil significantly inhibited both enzymes (IC50 of 650 µg/mL and IC50 of 2570 µg/mL, respectively) probably due to the dominance of limonene and sabinene. Neither EO exhibited antielastase properties, while the hydrolates from both ecotypes showed no antiageing activity, regardless of the enzyme tested. The EOs from the aerial parts of sea fennel from FRA and CRO differed greatly in composition, resulting in different activities. The Croatian samples appeared to have better biological properties and are therefore good candidates for applications as preservatives or antiageing agents.

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