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Metal–organic frameworks (MOFs) constitute an assorted class of multi-dimensional materials that offer the potential to serve as luminescent sensors for the sensitive and selective detection of antibiotics in wastewater. Herein, a new Zn(II)-based MOF with the formula [Zn(PMA)0.5(bbp)·H2O·DMA] (1) (bbp = 3,5-bis(benzoimidazo-1-ly)pyridine; PMA = pyromellitic acid) was synthesized by a solvothermal method and characterized. Crystallographic analysis reveals that MOF 1 possesses a 4,4-connected net with the Schläfli symbol {32·4·52·6}2{32·42·52}. The fabricated MOF exhibited luminescent property and was employed as a luminescent sensor to sensitively and selectively detect tetracycline (TCY) antibiotic amongst thiamphenicol (THI), 2-methyl-4-chlorophenoxyacetic acid (MCPA), tetracycline (TCY), sulfamethoxazole (SMT), thiabendazole (TBZ), tinidazole (TDZ), sulfadiazine (SDZ), chloramphenicol (CAP), metamitron (MMT), and dinotefuran (DTF). Further, restoration of the emissive response of TCY@1 was achieved by adding salicylic acid with a concomitant bathochromic shift in the emissive response. The possible sensing mechanism and restoration of emissive response were assessed with the aid of theoretical calculations. [ABSTRACT FROM AUTHOR]

Dayak tribes indigenous to the Indonesian island of Borneo has been using Bajakah Kalalawit (Uncaria gambir Roxb.) as traditional medicine for ages. This inspired us to develop phenolic from Bajakah Kalalawit extract as antibacterial agent. The extraction was done through decoction method and the determination of phenolic concentration was done using a visible spectrophotometer and Folin–Ciocalteu reagent (mixture of phosphotungstic and phosphomolybdic acids). We investigated the possibility of developing phenolic nanoparticle for future work. Kirby-Bauer method was used to assess antibacterial activity of phenolic against Staphylococcus aureus and the results were compared to Chloramphenicol in terms of its efficacy and duration of inhibition. This study contributes to the ongoing effort to address antibiotic resistance through the development of innovative antibacterial agents derived from natural sources. The results provide valuable insights into the potential of Bajakah Kalalawit phenolic extracts as a promising avenue for combating bacterial infections in the future. [ABSTRACT FROM AUTHOR]

Objectives: Antimicrobial resistance (AMR) poses a worldwide challenge, threatening global health. The objective of this research was to determine the 3rd generation cephalosporin resistance (3GCR) proportion in Escherichia (E.) coli isolated from clinical samples of dogs and cats in Germany. Methods: The study utilized result data from antimicrobial susceptibility testing (AST) of isolates obtained from diagnostic samples collected from dogs and cats send in for bacterial examination. Data includes AST results from 3,491 veterinary practices in Germany spanning the years 2019 to 2021, representing 33.1% of practices and clinics nationwide. Out of 175,171 clinical samples, a total of 25,491 E. coli strains (14,6%) were evaluated for their susceptibility to antimicrobials, in particular the 3rd generation cephalosporin cefovecin, but also aminoglycosides (gentamicin, GEN), fluoroquinolones (enrofloxacin, ENR), tetracyclines (doxycycline), phenicols (chloramphenicol), folate pathway inhibitors (sulfamethoxazole + trimethoprim), and nitrofurans (nitrofurantoin). Results: The cefovecin resistance proportion was 11.6% in the study period. Geographical analysis showed local variations in 3GCR in E. coli of ±3%. Regarding all E. coli isolates investigated, resistance proportions were observed as follows: 12% for sulfamethoxazole-trimethoprim, 7% for enrofloxacin, 8% for chloramphenicol and 4% for gentamicin. Notably, 3GCR E. coli showed significantly higher resistance proportions, specifically 30% for sulfamethoxazole-trimethoprim, 28% for chloramphenicol, 18% for enrofloxacin and 14% for gentamicin. Conclusions: This study represents the first of its kind to utilize an extensive dataset encompassing dogs and cats across Germany. Companion animals have close contact to their owners and transmission of 3GCR between them is likely as well as acquisition from other environmental sources. Resistance proportions (6.7%) against the antibiotic ceftazidime as reported by the German AMR surveillance for human medicine were lower than in our veterinary data. Our study provides an overview of the current 3GCR resistance proportion in Germany and demonstrates the importance of integrated AMR monitoring. [ABSTRACT FROM AUTHOR]

Background: Due to the increasing emergence of antibiotic resistance in Enterococcus faecalis (E. faecalis), it indicated as potentially opportunistic pathogen causing various healthcare-associated and life-threatening diseases around the world. Objective: The aim of this meta-analysis was to evaluate the weighted pooled resistance rates in clinical E. faecalis isolates based on over time, areas, antimicrobial susceptibility testing (AST), and infection source. Methods: We searched the studies in PubMed, Scopus, and Web of Science (November 30, 2022). All statistical analyses were carried out using the statistical package R. Results: The analysis encompassed a total of 74 studies conducted in 28 countries. According to the meta-regression, the chloramphenicol, fosfomycin, imipenem, linezolid, minocycline, norfloxacin, quinupristin-dalfopristin, and tetracycline resistance rate increased over time. Analysis revealed statistically significant differences in antibiotic resistance rates for ampicillin, chloramphenicol, erythromycin, gentamicin, penicillin, rifampicin, teicoplanin, tetracycline, and vancomycin across various countries. Conclusions: Globally, the prevalence of drug resistant E. faecalis strains are on the increase over time. Daptomycin and tigecycline can be an effective agent for the treatment of clinical E. faecalis infections. Considering the low prevalence of antibiotic resistance in continents of Europe and Australia, it is suggested to take advantage of their preventive strategies in order to obtain efficient results in other places with high prevalence of resistance. [ABSTRACT FROM AUTHOR]

With the increasing misuse of antibiotic drugs, the convenient and ultrasensitive detection of chloramphenicol (CAP) is essential for ensuring food safety and human health. In this study, a comprehensive platform was developed integrating detection and discrimination capabilities by combining surface-enhanced Raman scattering (SERS) with lateral flow immunoassay (LFIA) technology, along with a support vector machine (SVM) model for data analysis, to detect CAP residues in aquatic products. The CAP-specific antibody-modified gold nanostars (Au NSs) were synthesized as SERS–LFIA nanoprobes, achieving an ultralow limit of detection (LOD) of 10 pg/mL and a theoretical LOD of 1.6 pg/mL for simulated aquatic samples. This sensitivity surpasses that of the currently available commercial strips and demonstrates high specificity. Additionally, the automated discrimination model exhibited high sensitivity (95.83%) and specificity (96.43%) as well as an accuracy of 96% on the test set, marking an 8% improvement over traditional Raman intensity discrimination methods. This developed platform is a simple, fast, and automated technique that eliminates the need for sample pretreatment, offering a promising approach for the trace detection of CAP in aquatic products. [ABSTRACT FROM AUTHOR]

Rapid, efficient, versatile, easy-to-use, and non-expensive analytical approaches are globally demanded for food analysis. Many ambient ionization approaches based on electrospray ionization (ESI) have been developed recently for the rapid molecular characterization of food products. However, those approaches mainly suffer from insufficient signal duration for comprehensive chemical characterization by tandem MS analysis. Here, a commercially available disposable gel loading tip is used as a low-cost emitter for the direct ionization of untreated food samples. The most important advantages of our approach include high stability, and durability of the signal (> 10 min), low cost (ca. 0.1 USD per run), low sample and solvent consumption, prevention of tip clogging and discharge, operational simplicity, and potential for automation. Quantitative analysis of sulfapyridine, HMF (hydroxymethylfurfural), and chloramphenicol in real sample shows the limit-of-detection 0.1 μg mL−1, 0.005 μg mL−1, 0.01 μg mL−1; the linearity range 0.1–5 μg mL−1, 0.005–0.25 μg mL−1, 0.01–1 μg mL−1; and the linear fits R2 ≥ 0.980, 0.991, 0.986. Moreover, we show that tip-ESI can also afford sequential molecular ionization of untreated viscous samples, which is difficult to achieve by conventional ESI. We conclude that tip-ESI–MS is a versatile analytical approach for the rapid chemical analysis of untreated food samples. [ABSTRACT FROM AUTHOR]

Vibrioparahaemolyticus is a gram-negative motile bacterium inhabiting marine, estuarine, and coastal environments. It is a critical aquatic pathogen in shrimp farming, and strains possessing pir A and pir B toxins can cause acute hepatopancreatic necrosis disease (AHPND) in shrimps. The study aimed to isolate V. parahaemolyticus from the gut and hepatopancreas of shrimps from the selected districts of Tamil Nadu for a duration of 6 months from December 2022 to May 2023 by random sampling, and thirty-two strains were confirmed as V. parahaemolyticus from 110 presumptive bacterial isolates. All 32 isolates used in the AP4 PCR protocol failed to detect any isolates carrying AHPND pir toxins (pir A and pir B). Forty-four percent of isolates have shown β-haemolytic activity on blood agar. Of the 32 isolates, two, eleven, and twenty-nine harboured tdh, trh, and T3SS1 genes, respectively, and none of them possessed T3SS2 gene. Isolates of V. parahaemolyticus were resistant to gentamycin, vancomycin, and erythromycin and highly susceptible to ciprofloxacin, ofloxacin, chloramphenicol, amoxyclav, trimethoprim, streptomycin, cefoxitin, and ceftazidime. AMR genes encoding qnrA, tet A, blaSHV, and aac-3-IIa were present in 6%, 16%, 16%, and 22% of the isolates. AMR genes catA1 and str B were negative for all 32 isolates. It is concluded that the prevalence and incidence of V. parahaemolyticus were 29% in the studied coastal districts of Tamil Nadu. All isolates were found to be negative for AHPND. Hence, shrimp farms in the studied area were free from infection of AHPND. [ABSTRACT FROM AUTHOR]

Bacterial cytoplasmic organelles are diverse and serve many varied purposes. Here, we employed Rhodobacter sphaeroides to investigate the accumulation of carbon and inorganic phosphate in the storage organelles, polyhydroxybutyrate (PHB) and polyphosphate (PP), respectively. Using cryo-electron tomography (cryo-ET), these organelles were observed to increase in size and abundance when growth was arrested by chloramphenicol treatment. The accumulation of PHB and PP was quantified from three-dimensional (3D) segmentations in cryo-tomograms and the analysis of these 3D models. The quantification of PHB using both segmentation analysis and liquid chromatography and mass spectrometry (LCMS) each demonstrated an over 10- to 20-fold accumulation of PHB. The cytoplasmic location of PHB in cells was assessed with fluorescence light microscopy using a PhaP-mNeonGreen fusion-protein construct. The subcellular location and enumeration of these organelles were correlated by comparing the cryo-ET and fluorescence microscopy data. A potential link between PHB and PP localization and possible explanations for co-localization are discussed. Finally, the study of PHB and PP granules, and their accumulation, is discussed in the context of advancing fundamental knowledge about bacterial stress response, the study of renewable sources of bioplastics, and highly energetic compounds. [ABSTRACT FROM AUTHOR]

Limited literature exists on chloramphenicol's clinical use. In this retrospective, single-center case-series, we examined 183 chloramphenicol-treated and 81 piperacillin-tazobactam-treated medical patients. Chloramphenicol recipients were older, more debilitated, cognitively impaired, and penicillin allergic, while increased need for inotropics, higher leukocyte count, and higher creatinine levels were notable in the piperacillin-tazobactam group. Pneumonia was the most common indication, with no mortality difference between groups. While acknowledging its antimicrobial activity and potential benefit in specific conditions such as pneumonia, further clinical studies are needed to assess the role of chloramphenicol in the setting where other alternatives are available. [ABSTRACT FROM AUTHOR]

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). [ABSTRACT FROM AUTHOR]

A new coordination polymer (CP) with composition [Zn3(bpyp)2(TCB)2(H2O)2]n (1) has been engendered by performing reaction of Zn(II) with 1,3,5‐tris‐(4‐carboxyphenyl)benzene (H3TCB) and 2,5‐bis(pyrid‐4‐yl)pyridine (bpyp) under solvothermal condition. The single crystal X‐ray diffraction analysis for 1 suggests kgd topological behavior having resemblance with a tessellation composed of diamond shapes arranged in a star pattern and represented by the Schläfli symbol {41}2{42·62·81}. This newly designed CP exhibits optical band gap of 2.92 eV and employed as photocatalyst for photodegradation of antibiotics, namely, nitrofurazone (NFZ), chloramphenicol (CAP), sulfasalazine (SLA), oxytetracycline (OXY), and furazolidone (FZD). Among these antibiotics, 1 displays best photocatalytic activity against the photodegradation of NFZ and under optimized conditions viz. photocatalyst dosage of 15 mg, and initial NFZ concentration of 40 ppm, the CP 1 displays best catalytic performance and photo‐decomposed 93.04% NFZ with pseudo first order rate constant k of 0.04502 min−1 in 1 h. The likely photocatalytic mechanism has been evaluated using theoretical calculations. [ABSTRACT FROM AUTHOR]

As a broad-spectrum antibiotic, chloramphenicol has an important contribution in resisting bacterial diseases. It has been widely used in medicine and animal husbandry, but it has the disadvantages of long-term unreasonable use and slow degradation in nature. Long-term consumption of food contaminated by chloramphenicol will cause serious side effects to human beings. Therefore, it is urgent to establish an effective method to remove chloramphenicol from wastewater. Co/Ni@ZrO2 photocatalyst with nanosphere structure was prepared by hydrothermal method and used for the degradation of chloramphenicol (CAP).The structure, morphology and optical properties of the samples were characterized by TEM, SEM, XPS, XRD, FT-IR and UV-Vis. Under visible light, 12% Co/Ni@ZrO2 has good photocatalytic performance for the degradation of chloramphenicol, which may be due to the synergistic effect and nano-limitation effect between Co/Ni and ZrO2. When the optimal dosage of catalyst is 50 mg / L and the initial concentration of chloramphenicol is 20 mg / L, the degradation rate is 98.2 % within 150 min. XPS and Raman results showed that there were appropriate amount of oxygen vacancies on the surface of ZrO2, which accelerated the electron transfer rate in the system and inhibited the recombination of photoelectron-hole pairs under visible light, thus improving the activation efficiency of dissolved oxygen in chloramphenicol solution. Free radical capture experiments showed that· O2-,· OH, h+ were the main active substances for the degradation of chloramphenicol. The possible mechanism of chloramphenicol degradation under visible light was speculated. The results show that Co/Ni@ZrO2 is a promising photocatalyst for wastewater treatment. A schematic diagram of charge separation and transfer during the degradation of chloramphenicol by 12wt % CoNi @ ZrO2 nanospheres [ABSTRACT FROM AUTHOR]

Chloramphenicol (CAP) is an antibiotic that is used to treat a range of human ailments and is also utilized in animal medicine. However, long-term usage of CAP can have substantial side effects in humans. Hence, precise and sensitive analytical approaches for CAP detection are required. We developed an electrochemical sensor based on a ZnO/MWCNT nanocomposite for the efficient measurement of chloramphenicol (CAP) in this study. Aqueous leaf extract of Rhoeo discolor (Tradescantia spathacea) was employed in the green production of ZnO nanoparticles. A simple sonochemical approach was used to combine ZnO nanoparticles with MWCNT. UV–Visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), elemental mapping, Transmission Electron Microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) have been utilized to describe the synthesized ZnO nanoparticles. The electrochemical performance of the ZnO/MWCNT/graphite electrode was studied using cyclic voltammetry (CV) and linear sweep voltammetry (LSV). The effect of loading mass, pH, and scan rate on electrode reaction was also determined. The ZnO/MWCNT/graphite electrode has a linear response in the range of 1 to 250 μM, a high sensitivity of 11.15 μA μM−1 cm−2, with a LOD of 0.35 μM and LOQ of 1.16 μM. It also has good reproducibility and stability. Real samples like honey and milk were used to illustrate the sensor's viability. [ABSTRACT FROM AUTHOR]

PurposeMethodsResultsConclusionTopical chloramphenicol is one of the most ubiquitous antibiotics used in ophthalmology and oculoplastic surgery globally. It shows broad-spectrum activity against a variety of different pathogenic organisms, is well tolerated on the ocular surface and displays excellent topical pharmacokinetics. Chloramphenicol has been available for purchase over the counter in the United Kingdom since 2005. Despite this, the largest health economy in the world, The United States has had a de-facto moratorium on its use for the past 30 years. In this review, we aim to evaluate topical chloramphenicol in ophthalmology and oculoplastic surgery and to determine whether its reputation within the US is warranted and justified.We conducted a comprehensive literature review to evaluate the different facets of chloramphenicol, providing a detailed understanding of the drug, its historical context, the benefits and perceived risks, including safety concerns, and clinical perspectives of its use in clinical practice.The mechanism of chloramphenicol, the context around which the drug’s use in the US declined, and the drug’s evidence base and safety data, including published case reports of serious adverse events, were analysed. The perceived benefits of the drug, particularly in light of antimicrobial resistance and its economic impact, were reviewed. Finally, perspectives on its use in clinical practice in ophthalmology and associated allied specialities were presented.Chloramphenicol and its topical application have been misunderstood for many decades, particularly in the United States. Its demise across the Atlantic was due to an overzealous response to a dubious association with a weak evidence base. Numerous authors have since validated the safety profile of the and its safety has been borne out. The benefits of chloramphenicol, an effective broad-spectrum agent with a positive cost differential in the era of anti-microbial resistance and fiscal tightening, cannot be understated. Its likely effectiveness as a therapeutic topical agent in ophthalmic surgery makes it a valuable tool in the ophthalmic anti-microbial armoury. We would encourage the reinstatement of this valuable yet misunderstood drug as a first-line agent for simple ophthalmic infections. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial resistance (AMR) of Neisseria gonorrhoeae (NG) is a significant public health concern. Objective: The objective of our study was to assess global AMR rates and test them both temporally and geographically. Methods: We conducted a systematic search of relevant reports from international databases up to 2021. The R statistical package was used for all statistical analyses. Results: A total of 225 articles were analyzed, and 432,880 NG isolates were examined. The weighted pooled resistance (WPR) rate of different antibiotics was as follows: ciprofloxacin, 51.6%; tetracycline, 45.4%; trimethoprim/sulfamethoxazole, 42.4%; chloramphenicol, 4.1%; kanamycin, 2.1%; gentamicin, 0.6%; and spectinomycin, 0.3%. The resistance to spectinomycin, gentamicin, and kanamycin decreased over time. Significant differences in antibiotic resistance rates were found between the countries. Conclusion: Our findings reveal a continuous increase in resistance to some antibiotics (tetracycline and ciprofloxacin) historically used for gonorrhea, even after discontinuation. However, encouraging trends of decreasing resistance to spectinomycin, gentamicin, and kanamycin were observed. Continued global monitoring of AMR profiles in NG isolates is essential for informing appropriate treatment strategies and mitigating the threat of untreatable gonorrhea. [ABSTRACT FROM AUTHOR]

A decreased chloramphenicol susceptibility in Haemophilus influenzae is commonly caused by the activity of chloramphenicol acetyltransferases (CATs). However, the involvement of membrane proteins in chloramphenicol susceptibility in H. influenzae remains unclear. In this study, chloramphenicol susceptibility testing, whole-genome sequencing, and analyses of membrane-related genes were performed in 51 H. influenzae isolates. Functional complementation assays and structure-based protein analyses were conducted to assess the effect of proteins with sequence substitutions on the minimum inhibitory concentration (MIC) of chloramphenicol in CAT-negative H. influenzae isolates. Six isolates were resistant to chloramphenicol and positive for type A-2 CATs. Of these isolates, A3256 had a similar level of CAT activity but a higher chloramphenicol MIC relative to the other resistant isolates; it also had 163 specific variations in 58 membrane genes. Regarding the CAT-negative isolates, logistic regression and receiver operator characteristic curve analyses revealed that 48T > G (Asn16Lys), 85 C > T (Leu29Phe), and 88 C > A (Leu30Ile) in HI_0898 (emrA), and 86T > G (Phe29Cys) and 141T > A (Ser47Arg) in HI_1177 (artM) were associated with enhanced chloramphenicol susceptibility, whereas 997G > A (Val333Ile) in HI_1612 (hmrM) was associated with reduced chloramphenicol susceptibility. Furthermore, the chloramphenicol MIC was lower in the CAT-negative isolates with EmrA-Leu29Phe/Leu30Ile or ArtM-Ser47Arg substitution and higher in those with HmrM-Val333Ile substitution, relative to their counterparts. The Val333Ile substitution was associated with enhanced HmrM protein stability and flexibility and increased chloramphenicol MICs in CAT-negative H. influenzae isolates. In conclusion, the substitution in H. influenzae multidrug efflux pump HmrM associated with reduced chloramphenicol susceptibility was characterised. [ABSTRACT FROM AUTHOR]

Objectives: The objective of the study was to identify bacterial pathogens and their antimicrobial sensitivity profile associated with cases of canine progressive ulcerative keratitis. Materials and Methods: Analysis of microbial culture and sensitivity results from dogs with progressive ulcerative keratitis presenting to a UK referral practice between December 2018 and August 2020. Results: Positive bacterial cultures were obtained from 80/148 (54%) of the canine ulcers sampled with 99 bacterial isolates cultured. Streptococcus canis (n = 29), Pseudomonas aeruginosa (n = 19), and Staphylococcus pseudintermedius (n = 16) were the most common isolates. Pseudomonas aeruginosa was more likely to be isolated whether the ulcer was clinically malacic at the time of sampling (OR = 10.1, p <.001). Ulcers treated prior to culture with fusidic acid were 7.6 times more likely to be positive than those treated with any other antimicrobial(s). Bacterial isolates demonstrated resistance against neomycin (85%), fusidic acid (78%), and tetracycline (68%). Conversely, isolates were most likely to be sensitive to gentamicin (88%), ofloxacin (77%), ciprofloxacin (73%), and chloramphenicol (64%). Antimicrobial combinations of chloramphenicol or gentamicin with a fluoroquinolone (ofloxacin or ciprofloxacin) or chloramphenicol combined with gentamicin were the most effective on in vitro analysis (over 90% susceptibility of all isolates). Conclusion: The most common bacterial species associated with canine progressive ulcerative keratitis in a UK referral population were S. canis, P. aeruginosa, and S. pseudintermedius. Combination antimicrobial therapy is recommended pending culture and sensitivity results given the varied antimicrobial susceptibility profiles and significant bacterial in vitro resistance to antimicrobial monotherapy. [ABSTRACT FROM AUTHOR]

In this study, the genome of Akkermansia muciniphila ONE (designated AKK ONE) was sequenced, assembled, and analyzed. In addition, the safety of this strain was further evaluated by toxicological studies. The results showed that the AKK ONE genome is contained on a single chromosome with a total length of 2,817,524 bp and an average GC content of 55.48%. In total, 2411, 1131, 1168, 1745, and 1402 genes were annotated to the NR, GO, KEGG, COG, and SwissProt database, respectively. Potential resistance genes, adeF, tetW, ANT(3″)-IIa, and aadA1 were detected. AKK ONE was sensitive to ampicillin, ceftriaxone, cefotaxime, meropenem, tetracycline, and chloramphenicol and resistant to moxifloxacin. No potential virulence-related genes were detected. The PathogenFinder database analysis showed that AKK ONE was a non-potential human pathogen. This strain had good gastroenteric fluid tolerance and a weak ability to colonize the gut. No test item-related adverse effects were observed in the acute and subchronic toxicity test. AKK ONE did not display mutagenic activity either. This strain did not change the hematological and clinical biochemical parameters of mice. The weights of the organs were not affected by AKK ONE treatment. These results support that AKK ONE is safe for use as a probiotic at a dose of 8.28 × 109 CFU/kg bw/day. [ABSTRACT FROM AUTHOR]

This study examined the hematinic effect of the aqueous leaf extracts of Moringa oleifera (MOAE) and Carica papaya (CPAE). Thirty-six physically fit and disease-free rats in adulthood were partitioned into six groups, consisting of six rats per group. Group 1 acted as the nonanemic control group and was given 5ml/kg of distilled water. Anemia was generated in rats in groups 2 to 6 with the oral administration of chloramphenicol at a dosage of 50 mg/kg. Group 2 acted as the anemic control group and was given 5ml/kg of distilled water. Group 3 was given 100 mg/kg of ferrous gluconate. Groups 4 to 6 were given 500 mg/kg of MOAE, 500 mg/kg of CPAE, and a combination of 500 mg/kg of MOAE and 500 mg/kg of CPAE, respectively. The treatment was administered orally for 28 days, following which the PCV, Hb, and WBC count of the animal models were examined. The results demonstrated that chloramphenicol caused a statistically significant reduction in PVC and Hb, indicating anemia, as well as a significant rise in WBC count. MOAE and CPAE resulted in a statistically significant rise in PCV and Hb levels, along with a reduction in white blood cell (WBC) count. The hematinic impact seen when the extracts were given together was significantly greater (p< 0.05) than when either extract was given alone. The extracts of Moringa oleifera and Carica papaya showed an additional blood-building impact when given together. This observation may be beneficial for managing anemia. [ABSTRACT FROM AUTHOR]

In this study, a various weight percentage (50, 100, and 150 wt%) of g-C3N4 embedded NiO nanocomposite was synthesized by thermal polymerization followed by a simple hydrothermal technique. The synthesized photocatalysts were thoroughly characterized by employing sophisticated instrument methods such as p-XRD, HR-TEM, HR-XPS, UV–Vis DRS, and PL. The optimum incorporation of g-C3N4 (100 wt%) into the NiO system significantly increased the photocatalytic degradation of antibiotic chloramphenicol (CPL) with a percentage of 93.95% after 150 min of light exposure. Similarly, the Ni-CN-150 nanocomposite successfully degraded anionic direct violet 51 azo dye at 90.42% after 120 min of light irradiation. The efficient decrease of electron–hole recombination by transferring electrons between junctions improved photocatalytic degradation. The nanocomposite remained stable after six cycles of degradation for CPL and DV 51 pollutants in recycling trials. Quenching investigations identified the main reactive species that degrade pollutants and detailed the likely photocatalytic reaction process. [ABSTRACT FROM AUTHOR]

Introduction: Since its discovery in 1961, methicillin-resistant Staphylococcus aureus (MRSA) has been recognized as a significant healthcare-associated pathogen (HA-MRSA) and a notorious 'superbug'. Typing is crucial for surveillance, epidemiology analysis, infection control of MRSA and sequencing of the spa gene is one of the most common methods used for determining the origin of this bacterium in humans and animals. This research aimed to determine the antibiotic resistance and spa type of S. aureus strains collected from outpatients in two hospitals in the Wasit province of Iraq. Material & Methods: The study analyzed 200 outpatient MRSA isolates by collecting nasal and sputum samples from patients. Standard biochemical and molecular methods based on the nuc gene were used to identify S. aureus bacteria and amplify the mecA and spa genes. The Kirby-Bauer disc diffusion method was employed to determine the antibiotic sensitivity of the isolates using penicillin, cefoxitin, vancomycin, gentamicin, erythromycin, tetracycline, imipenem, clindamycin, chloramphenicol and rifampicin. Results: Methods. The prevalence of MRSA was more common in women than in men. Antibiogram results showed that most of the isolates were resistant to penicillin (94.2%) and sensitive to imipenem (100%), clindamycin (100%), and chloramphenicol (100%). Of these 35 isolates, 30 (87.5%) and 26 strains (74.3%) were positive for the mecA and spa genes. Typing based on spa gene sequencing revealed four different patterns: t386, t3579, U0002 and U0234. Conclusion: Variations in the spa gene among different S. aureus isolates may he of clinical importance when treating staphylococcal infections. In this study, spa typing revealed four different patterns in Iraq, representing diagnostic and therapeutic implications. [ABSTRACT FROM AUTHOR]

In this study, molecular identification of Lactiplantibacillus pentosus v390 was performed using 16S rRNA gene analysis with FYM27 and R1492 primers. The viability of the strain was assessed under acidic conditions at pH 2.5, 3.5 and 4.5, and resistance to bile at concentrations of 0%, 0.3%, 0.5%, and 0.7% was investigated. Antioxidant activity, cholesterol absorption, hydrophobicity, potential for DNase enzyme production, biogenic amines, hemolytic activity, and resistance to common therapeutic antibiotics were evaluated. The antimicrobial effect of the strain against pathogenic bacteria (Shigella dysenteriae, Salmonella enterica serovar Typhimurium, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Bacillus subtilis) was examined using the well and disk diffusion method. The results showed that the L. pentosus v390 strain had the ability to survive at different pH levels, but after three hours of storage at pH 2.5, the bacterial count decreased. The strain demonstrated growth capability at various bile salt concentrations. L. pentosus v390 was intermediate to the antibiotic Nitrofurazone, resistant to Nalidixic and Imipenem antibiotics, and sensitive to Vancocin, Gentamicin, Chloramphenicol, Penicillin, and Ciprofloxacin antibiotics. The hydrophobicity, antioxidant activity (DPPH and ABTS), and cholesterol absorption of the strain were 46.50 ± 0.38%, 37.20 ± 0.40%, 39.90 ± 0.45%, and 36.50 ± 0.47%, respectively. No DNase enzyme production, biogenic amines, or hemolytic activity were observed from the strain. L. pentosus v390 exhibited stronger antimicrobial effects against Gram -positive bacteria. The results indicated that L. pentosus v390 has desirable probiotic properties that require further research to confirm its application potential in food product development. [ABSTRACT FROM AUTHOR]

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A photocatalytic electrochemical aptasensor for the detection of chloramphenicol（CAP）antibiotic residues in water by utilizing SYBR Green I（SG）and chemically exfoliated MoS 2 （ce-MoS 2 ） as synergistically signal-amplification platforms. [Display omitted] • A novel photocatalytic electrochemical aptasensor was developed for the detection of chloramphenicol (CAP) antibiotic residues in water. • Photosensitized SYBR Green I (SG) and chemically stripped MoS 2 (ce-MoS 2) were intercalated into the groove of the resulting dsDNA and use as a synergistic signal-amplification platform. • Upon light irradiation, the photocatalytic reaction was activated, generating singlet oxygen that efficiently cleaved the dsDNA, leading to a significant increase in the current of [Fe(CN) 6 ]3-/4-. • The aptasensor demonstrated good selectivity towards CAP in the presence of interfering antibiotics. • The aptasensor exhibited a linear relationship between CAP and logarithmic concentrations from 20 to 1000 nM, with a detection limit (3σ) of 3.391 nM. This study reports the development of a photocatalytic electrochemical aptasensor for the purpose of detecting chloramphenicol (CAP) antibiotic residues in water by utilizing SYBR Green I (SG) and chemically exfoliated MoS 2 (ce-MoS 2) as synergistically signal-amplification platforms. The Au nanoparticles (AuNPs) were electrodeposited onto the surface of an indium tin oxide (ITO) electrode. After that, the thiolate-modified cDNA, also known as capture DNA, was combined with the aptamer. Subsequently, photosensitized SG molecules and ce-MoS 2 nanomaterial were inserted into the groove of the resultant double-stranded DNA (dsDNA). The activation of the photocatalytic process upon exposure to light resulted in the generation of singlet oxygen. The singlet oxygen effectively split the dsDNA, resulting in significant enhancement in the current of [Fe(CN) 6 ]3-/4-. When the CAP was present, both SG molecules and ce-MoS 2 broke away from the dsDNA, which turned off the photosensitization response, leading to significant reduction in the current of [Fe(CN) 6 ]3-/4-. Under the optimal conditions, the aptasensor exhibited a linear relationship between the current of [Fe(CN) 6 ]3-/4- with logarithmic concentrations of CAP from 20 to 1000 nM, with a detection of limit (3 σ) of 3.391 nM. The aptasensor also demonstrated good selectivity towards CAP in the presence of interfering antibiotics, such as tetracycline, streptomycin, levofloxacin, ciprofloxacin, and sulfadimethoxine. Additionally, the results obtained from the analysis of natural water samples using the proposed aptasensor were consistent with the findings acquired through the use of a liquid chromatograph-mass spectrometer. Therefore, with its simplicity and high selectivity, this aptasensor can potentially detect alternative antibiotics in environmental water samples by replacing the aptamers based on photosensitization. [ABSTRACT FROM AUTHOR]

Chloramphenicol (CAP) is widely used in human and veterinary medicine but has a harmful side effect on human/animal health and ecological risks. The current methods for the detection of CAP are commonly expensive, complex and time-wasting. Herein, a simple, low-cost and high-effective electrochemical sensor is constructed for the detection of CAP using rationally designed pitch-derived porous carbon (PPC) as the conducting medium. The modification of PPC on the glassy carbon electrode is adopted to realize the amplification of electrochemical signal, and then the aptamers with negative charge are introduced to the PPC-functionalized electrode to attract the positively charged CAP and to enhance hydrophilicity of the modified electrode. The electrochemical performance of the fabricated sensor is investigated using cyclic voltammetry and differential pulse voltammetry, showing a fast current change and high-selectivity for the detection of CAP, and exhibiting outstanding sensing performance with a wide linear range of 1.0–500 μM and a low detection limit of 0.1 μM. In addition, the sensor also shows excellent repeatability (RSD = 4.1%), reproducibility (RSD = 5.0%), stability (RSD = 8.3%) and high selectivity. Moreover, the constructed sensor is capable of precisely detecting CAP in real water samples with recoveries of 93.0% to 102.8% and relative standard deviations of less than 4.5%. [ABSTRACT FROM AUTHOR]

Antibiotic resistance genes (ARGs) benefit host bacteria in environments containing corresponding antibiotics, but it is less clear how they are maintained in environments where antibiotic selection is weak or sporadic. In particular, few studies have measured if the direct effect of ARGs on host fitness is fixed or if it depends on the host strain, perhaps marking some ARG–host combinations as selective refuges that can maintain ARGs in the absence of antibiotic selection. We quantified the fitness effects of six ARGs in 11 diverse Escherichia spp. strains. Three ARGs (blaTEM-116, cat and dfrA5, encoding resistance to β-lactams, chloramphenicol, and trimethoprim, respectively) imposed an overall cost, but all ARGs had an effect in at least one host strain, reflecting a significant strain interaction effect. A simulation predicts these interactions can cause the success of ARGs to depend on available host strains, and, to a lesser extent, can cause host strain success to depend on the ARGs present in a community. These results indicate the importance of considering ARG effects across different host strains, and especially the potential of refuge strains to allow resistance to persist in the absence of direct selection, in efforts to understand resistance dynamics. [ABSTRACT FROM AUTHOR]

Canine urinary excretion of chloramphenicol was evaluated to optimize a dosing protocol for treating urinary tract infections. Seven healthy male intact purpose‐bred Beagles and six healthy client‐owned dogs of various breeds each received a single oral 50 mg/kg dose of chloramphenicol. Urine was collected at baseline, and 6, 8, 12, and 24 h after chloramphenicol. Chloramphenicol urine concentrations were measured and compared to the epidemiological cutoff value for E. coli (16 mcg/mL). At 8 h, mean chloramphenicol concentration from all dogs was 266.9 mcg/mL (90% CI 136.2–397.7 mcg/mL) but was lower in Beagles than client‐owned dogs. At 12 h, mean chloramphenicol concentration from all dogs was 111.0 mcg/mL (90% CI 36.9–185.0 mcg/mL) and was lower in Beagles (10.6 mcg/mL, 90% CI 1.4–19.8 mcg/mL) than client‐owned dogs (228.0 mcg/mL, 90% CI 103.0–353.1 mcg/mL). Urine half‐life was similar for all dogs (1.8–3.8 h). This justifies dosing chloramphenicol 50 mg/kg PO q 8 h. All client‐owned dogs additionally maintained concentrations well above 16 mcg/mL, for 12 h, suggesting that q 12‐h dosing might be appropriate for non‐Beagle dogs with susceptible lower urinary tract infections. A clinical trial in dogs with urinary tract infections is needed as well as further investigation into potential breed differences. [ABSTRACT FROM AUTHOR]

Aims Enterococcus faecalis (E. faecalis) is a leading cause of nosocomial infection and presents a wide spectrum of antibiotic resistance, being vancomycin-resistant Enterococcus (VRE) one of the most relevant. Synthetic antimicrobial peptides (SAMPs) are currently a promising option to overcome antimicrobial resistance. Thus, the purpose of this study was to assess the effect of eight SAMPs against vancomycin-resistant E. faecalis , as well as to investigate their mechanism of action and synergy with conventional antibiotics. Methods and results Here, eight SAMPs, Mo -CBP3-PepI, Mo -CBP3-PepII, Mo -CBP3-PepIII, Rc Alb-PepI, Rc Alb-PepII, Rc Alb-PepIII, PepGAT, and PepKAA, were tested for antibacterial activity in vitro against E. faecalis (ATCC® 51299) through broth microdilution. A maximum of 48% of E. faecalis growth inhibition was achieved by treatment with SAMPs alone. However, when these peptides were combined with the antibiotic chloramphenicol, assessed by checkerboard method, the inhibition increased to 55%–76% of inhibition, two to three-folds of increase if compared to the effects of the compounds alone. Microscopic analysis showed that E. faecalis cells treated with a combination of SAMPs and chloramphenicol resulted in bacterial membrane damage. The biofilm inhibition maximum was 22% for SAMPs alone, when combined with chloramphenicol, the maximum increased to 33%. Conclusions SAMPs and their combination with chloramphenicol demonstrate antibacterial activity against E. faecalis , possibly by inducing bacterial membrane damage. [ABSTRACT FROM AUTHOR]

The use of z-drugs has increased worldwide since its introduction. Although the prescribing patterns of hypnotics differ among countries, zolpidem is the most widely used z-drug in the world. Zolpidem may be involved in poisoning and deaths. A simple and fast HPLC-PDA method was developed and validated. Zolpidem and the internal standard chloramphenicol were extracted from plasma using a sonication-assisted dispersive liquid–liquid microextraction procedure. The method was validated including selectivity, linearity, precision, accuracy, and recovery. The calibration range (0.15–0.6 µg/mL) covers therapeutic and toxic levels of zolpidem in plasma. The limit of quantification was set at 0.15 µg/mL. Intra- and interday accuracy and precision values were lower than 15% at the concentration levels studied. Excellent recovery results were obtained for all concentrations. The proposed method was successfully applied to ten real postmortem plasma samples. In our series, multiple substances (alcohol and/or other drugs) were detected in most cases of death involving zolpidem. Our analytical method is suitable for routine toxicological analysis. [ABSTRACT FROM AUTHOR]

Pyocyanin is a blue-green phenazine pigment and one of the most virulent factors produced by the opportunistic pathogen Pseudomonas aeruginosa. It has a redox activity and a toxic impact on living cells, as it interacts with oxygen to produce reactive oxygen species (ROS). Using antibiotics at a sub-lethal dose has an unexpected influence on the expression of pyocyaninproducing genes. In this study, qPCR technique was performed to identify the effect of eight antibiotics (cefotaxime, ampicillin, amoxiclav, ceftazidime, ceftriaxone, chloramphenicol, kanamycin and tetracycline) on the gene expression level of pyocyanin synthetic genes in P. aeruginosa isolated from different clinical sources of a few hospitals in Mosul, Iraq using qPCR technique. It was found that when P. aeruginosa was grown in media containing cefotaxime (CTX 30 µg/mL), ampicillin (AM 25 µg/mL) or amoxiclav (AMC 30 µg/mL), up-regulated the expression of pyocyanin producing genes belonging to different operons thereby increased pyocyanin production. Overexpression occurred in (CTX) treatment in PhzA1 operon with 235.56 fold change and phzM and phzS genes with 340.14, 280.13 fold change, respectively. Lower expression levels showed in tetracycline (TE 30 µg/mL) treatment, which was a (1.44) fold change for phzA1 and a (1.64, 1.08) fold change for phzM and phzS genes. More caution should be considered when delivering antibiotics to treat P. aeruginosa infections, as using drugs that the bacteria resists or at sub-lethal concentrations may trigger up-regulation of virulence factors, aiding in the spread of the disease. [ABSTRACT FROM AUTHOR]

Background: The paediatric use of ophthalmic chloramphenicol in New Zealand (NZ) is relatively high; however, little more is known about its utilisation, including whether this is equitable. This study aimed to describe chloramphenicol utilisation in NZ children aged five years and under, by patient ethnicity, socioeconomic deprivation, and urban/non-urban domicile. Methods: This analysis included every publicly subsidised chloramphenicol dispensing received from birth to five years of age, for every child born in NZ in 2013. Cumulative proportion of first exposure, dispensing rate per person-year, and seasonality of dispensing were quantified. These were calculated following stratification by ethnicity, socioeconomic deprivation quintile, and urban/non-urban health district. For cumulative proportion of first exposure, odds ratios (OR) were calculated and multivariate logistic regression was performed. For dispensing rate, incidence rate ratios (IRR) were calculated and zero-inflated Poisson regression was performed. Results: Almost one-quarter of NZ children received their first dispensing within the first year of life. By five years of age, 55.2% of children had received their first dispensing. By five years of age, children of Pacific ethnicity, those in the highest deprivation quintile, and in those non-urban health districts had lower odds of receiving chloramphenicol (adjusted OR 0.90, 0.79, and 0.81, respectively, all p < 0.001). In contrast, children of Māori ethnicity had higher odds (adjusted OR 1.99, p < 0.001). Māori and Pacific ethnicity, and residence in non-urban health districts, were associated with fewer dispensings (adjusted IRR 0.88, 0.75 and 0.87, all p < 0.001). In contrast, deprivation quintile was not significantly associated with dispensing rate. Conclusion: Chloramphenicol utilisation is prevalent among NZ children, and utilisation may be lower among children of Pacific ethnicity and those in non-urban areas [ABSTRACT FROM AUTHOR]

Bacteria are a major cause of superficial eye infections, especially in children. The present study aimed to (i) determine the antimicrobial susceptibility patterns of ocular bacterial pathogens recovered in 20 laboratories during the period 2020–2021 and (ii) compare these results to those from three studies of the same design conducted in 2004, 2009, and 2015 in Germany. Cut-off values defined by EUCAST were used as breakpoints. A total of 1366 bacterial isolates were collected. The most frequent ocular specimens were conjunctival smears (54.3%). Susceptibility rates of Staphylococcus aureus (n = 594), Haemophilus influenzae (n = 178), and Streptococcus pneumoniae (n = 149) to chloramphenicol, gentamicin, kanamycin, neomycin, levofloxacin, ofloxacin, and oxytetracycline were >90% each. Overall, only minor changes in resistance levels were observed in the period since 2004. Therefore, all tested antimicrobials can still be recommended for local therapy of ocular surface infections. [ABSTRACT FROM AUTHOR]

The persistent, formidable sterilizing efficacy of Chloramphenicol (CAP) continues to promote its illicit use in the fields of aquaculture and animal husbandry, notwithstanding rigorous bans. In an effort to substantially reduce the adverse effects arising from CAP residues, an inexpensive and straightforward terahertz (THz) immunosensing platform that exploiting the nanoscale Au film metamaterial (AuF MM) coupled with an immunocompetitive assay. Small molecules of CAP-BSA anchor to the silicon-based AuF MM solid-phase substrate through hydrophobic interactions. Subsequently, these molecules and CAP standards participate in a competitive binding with colloidal gold (AuNPs) labeled-CAP monoclonal antibodies (mAb). The resulting change in spectral transmittance, caused by the THz waves' interaction with the refractive index response elicited by both the gold particles and the formed complexes on the AuF MM surface, is exploited for the qualitative assessment of CAP residues in milk. The heightened transmission of THz waves diminishes interference from the milk matrix, achieving satisfactory detection limits as low as 5 pg/mL. This demonstrates that we have effectively developed a straightforward yet efficacious strategy for THz detection that is both sensitive and specific. This strategy is anticipated to furnish a novel analytical method for the identification of proscribed molecules or deleterious viruses in foodstuffs and agricultural commodities. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the potential mechanisms associated with the persistence of chloramphenicol (CHP) resistance in Escherichia coli and Salmonella enterica isolated from pigs, pork, and humans in Thailand. The CHP-resistant E. coli (n = 106) and Salmonella (n = 57) isolates were tested for their CHP susceptibility in the presence and absence of phenylalanine arginine β-naphthylamide (PAβN). The potential co-selection of CHP resistance was investigated through conjugation experiments. Whole genome sequencing (WGS) was performed to analyze the E. coli (E329, E333, and E290) and Salmonella (SA448, SA461, and SA515) isolates with high CHP MIC (32–256 μg/mL) and predominant plasmid replicon types. The presence of PAβN significantly reduced the CHP MICs (≥4-fold) in most E. coli (67.9%) and Salmonella (64.9%). Ampicillin, tetracycline, and streptomycin co-selected for CHP-resistant Salmonella and E. coli-transconjugants carrying cmlA. IncF plasmids were mostly detected in cmlA carrying Salmonella (IncFIIAs) and E. coli (IncFIB and IncF) transconjugants. The WGS analysis revealed that class1 integrons with cmlA1 gene cassette flanked by IS26 and TnAs1 were located on IncX1 plasmid, IncFIA(HI1)/HI1B plasmids and IncFII/FIB plasmids. IncFIA(HI1)/HI1B/Q1in SA448 contained catA flanked by IS1B and TnAs3. In conclusion, cross resistance through proton motive force-dependent mechanisms and co-selection by other antimicrobial agents involved the persistence of CHP-resistance in E. coli in this collection. Dissemination of CHP-resistance genes was potentially facilitated by mobilization via mobile genetic elements. [ABSTRACT FROM AUTHOR]

Β-lactamases-producing Escherichia coli are a widely distributed source of antimicrobial resistance (AMR), for animals and humans. Little is known about the sensitivity profile and genetic characteristics of E. coli strains isolated from domestic cats. We report a cross-sectional study that evaluated E. coli strains isolated from domestic cats in Panama. For this study the following antibiotics were analyzed: ampicillin, amoxicillin-clavulanate cefepime, cefotaxime, cefoxitin, ceftazidime, aztreonam, imipenem, gentamicin, kanamycin, streptomycin, tetracycline, ciprofloxacin, nalidixic acid, trimethoprim-sulfamethoxazole, and chloramphenicol. The data obtained were classified as resistant, intermediate, or sensitive. MDR strains were established when the strain presented resistance to at least one antibiotic from three or more antimicrobial classes. Forty-eight E. coli isolates were obtained, of which 80% presented resistance to at least one of the antibiotics analyzed, while only 20% were sensitive to all (p = 0.0001). The most common resistance was to gentamicin (58%). Twenty-nine percent were identified as multidrug-resistant isolates and 4% with extended spectrum beta-lactamase phenotype. The genes blaTEM (39%), blaMOX(16%), blaACC (16%) and blaEBC (8%) were detected. Plasmid-mediated resistance qnrB (25%) and qnrA (13%) are reported. The most frequent sequence types (STs) being ST399 and we reported 5 new STs. Our results suggest that in intestinal strains of E. coli isolated from domestic cats there is a high frequency of AMR. [ABSTRACT FROM AUTHOR]

Florfenicol (Ff) is an antimicrobial agent belonging to the class amphenicol used for the treatment of bacterial infections in livestock, poultry, and aquaculture (animal farming). It inhibits protein synthesis. Ff is an analog of chloramphenicol, an amphenicol compound on the WHO essential medicine list that is used for the treatment of human infections. Due to the extensive usage of Ff in animal farming, zoonotic pathogens have developed resistance to this antimicrobial agent. There are numerous reports of resistance genes fromorganisms infecting or colonizing animals found in human pathogens, suggesting a possible exchange of genetic materials. One of these genes is floR, a gene that encodes for an eux pump that removes Ff from bacterial cells, conferring resistance against amphenicol, and is often associated with mobile genetic elements and other resistant determinants. In this study, we analyzed bacterial isolates recovered in rural Thailand from patients and environmental samples collected for disease monitoring. Whole genome sequencing was carried out for all the samples collected. Speciation and genome annotation was performed revealing the presence of the floR gene in the bacterial genome. The minimum inhibitory concentration (MIC) was determined for Ff and chloramphenicol. Chromosomal and phylogenetic analyses were performed to investigate the acquisition pattern of the floR gene. The presence of a conserved floR gene in unrelated Acinetobacter spp. isolated from human bacterial infections and environmental samples was observed, suggesting multiple and independent inter-species genetic exchange of drug-resistant determinants. The floR was found to be in the variable region containing various mobile genetic elements and other antibiotic resistance determinants; however, no evidence ofHGT could be found. The floR gene identified in this study is chromosomal for all isolates. The study highlights a plausible impact of antimicrobials used in veterinary settings on human health. Ff shares cross-resistance with chloramphenicol, which is still in use in several countries. Furthermore, by selecting for floR-resistance genes, we may be selecting for and facilitating the zoonotic and reverse zoonotic exchange of other flanking resistance markers between human and animal pathogens or commensals with detrimental public health consequences. [ABSTRACT FROM AUTHOR]

Background: Antibiotic resistance is a global public health concern that has been exacerbated by the overuse and misuse of antibiotics, leading to the emergence of resistant bacteria. The gut microbiota, often influenced by antibiotic usage, plays a crucial role in overall health. Therefore, this study aimed to investigate the prevalence of antibiotic resistant genes in the gut microbiota of Indonesian coastal and highland populations, as well as to identify vancomycin-resistant bacteria and their resistant genes. Methods: Stool samples were collected from 22 individuals residing in Pacet, Mojokerto, and Kenjeran, Surabaya Indonesia in 2022. The read count of antibiotic resistant genes was analyzed in the collected samples, and the bacterium concentration was counted by plating on the antibiotic-containing agar plate. Vancomycin-resistant strains were further isolated, and the presence of vancomycin-resistant genes was detected using a multiplex polymerase chain reaction (PCR). Results: The antibiotic resistant genes for tetracycline, aminoglycosides, macrolides, beta-lactams, and vancomycin were found in high frequency in all stool samples (100%) of the gut microbiota. Meanwhile, those meant for chloramphenicol and sulfonamides were found in 86% and 16% of the samples, respectively. Notably, vancomycin-resistant genes were found in 16 intrinsically resistant Gram-negative bacterial strains. Among the detected vancomycin-resistant genes, vanG was the most prevalent (27.3%), while vanA was the least prevalent (4.5%). Conclusion: The presence of multiple vancomycin resistance genes in intrinsically resistant Gram-negative bacterial strains demonstrated the importance of the gut microbiota as a reservoir and hub for the horizontal transfer of antibiotic resistant genes. [ABSTRACT FROM AUTHOR]

The objective aims to investigate the effects of individual and combined supplementation of Macleaya extract and chlortetracycline in the diet on intestinal health and gut microbiota of 2-17 weeks laying hens, and to explore the anti infective effect of Macleaya extract. A total of 1 440 1-day old Hailan brown female chicks were selected and randomly divided into four treatments, with 12 replicates per treatment and 30 chickens per replicate. Four groups of chickens were fed with basic diet, basic diet + 500 mg/kg Macleaya extract, basic diet + 50 mg/kg chloramphenicol, and basic diet+500 mg/kg Macleaya extract + 50 mg/kg chloramphenicol. The experiment lasted for a total of 17 weeks, with basic feed being fed for 1-7 days. Starting from the 8th day, feeding of chick rearing period feed was carried out. Starting from the seventh and 13th weeks, feeding of early and late stage feed was carried out, respectively. The results indicate that: compared with the control group, the MCE group showed a decrease in the comprehensive small intestine score at six weeks (P<0.05); the combined group showed a decrease in the comprehensive small intestine score at six weeks and the duodenal and ileal scores at 17 weeks (P<0.05). Compared with the control group, the Simpson index and relative abundance of Firmicutes in the MCE group increased (P<0.05), while the relative abundance of Rikenellaceae decreased (P<0.05); the Chao1 index and relative abundance of Rikenellaceae in the CC group decreased, while the Simpson index and relative abundance of Prevotellaceae increased (P<0.05); the combination group showed an increase in Simpson's index (P<0.05). Compared with the three experimental groups, the ACE index and Chao1 index of the MCE group and the combination group were significantly higher than those of the CC group (P<0.05), while the relative abundance of Prevotellaceae in the combination group was significantly lower than that in the CC group (P<0.05). From this, it can be seen that MCE can reduce small intestine score, improve the microbiota structure of the cecum, and be beneficial for maintaining intestinal health and microbial balance. Its effect is significantly better than CC. [ABSTRACT FROM AUTHOR]

A facile method which combines the advantages of carbon quantum dots and molecular imprinting technology to design a fluorescence molecular imprinting sensor for the high sensitivity and selective detection of chloramphenicol. The fluorescent molecule imprinted polymers are synthesized by sol-gel polymerization using carbon quantum dots as functional monomers and fluorescent sources, TEOS as crosslinkers, breaking with the traditional understanding of an additional functional monomer. Under optimal experimental, as the concentration of chloramphenicol increases, the fluorescence intensity of the fluorescence molecule imprinting sensor gradually decreases. The concentration of chloramphenicol is linear in the range of 5–100 µg/L and the detection limit is 1 µg/L (N/S = 3). The sensor is able to detect chloramphenicol in milk, enabling the application of real samples. The results show that this work provides an easy method to preparing fluorescent molecular imprinting sensors for the detection of chloramphenicol in milk. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance is considered one of the most critical threat for both human and animal health. Recently, reports of infection or colonization by carbapenemase-producing Enterobacterales in companion animals had been described. This study report the first molecular characterization of NDM-producing Enterobacterales causing infections in companion animals from Argentina. Nineteen out of 3662 Enterobacterales isolates analyzed between October 2021 and July 2022 were resistant to carbapenemes by VITEK2C and disk diffusion method, and suspected to be carbapenemase-producers. Ten isolates were recovered from canine and nine from feline animals. Isolates were identified as K. pneumoniae (n = 9), E. coli (n = 6) and E. cloacae complex (n = 4), and all of them presented positive synergy among EDTA and carbapenems disks, mCIM/eCIM indicative of metallo-carbapenemase production and were also positive by PCR for blaNDM gene. NDM variants were determined by Sanger sequencing method. All 19 isolates were resistant to β-lactams and aminoglycosides but remained susceptible to colistin (100%), tigecycline (95%), fosfomycin (84%), nitrofurantoin (63%), minocycline (58%), chloramphenicol (42%), doxycycline (21%), enrofloxacin (5%), ciprofloxacin (5%) and trimethoprim/sulfamethoxazole (5%). Almost all isolates (17/19) co-harbored blaCTX-M plus blaCMY, one harbored blaCTX-M alone and the remaining blaCMY. E. coli and E. cloacae complex isolates harbored blaCTX-M-1/15 or blaCTX-M-2 groups, while all K. pneumoniae harbored only blaCTX-M-1/15 genes. All E. coli and E. cloacae complex isolates harbored blaNDM-1, while in K. pneumoniae blaNDM-1 (n = 6), blaNDM-5 (n = 2), and blaNDM-1 plus blaNDM-5 (n = 1) were confirmed. MLST analysis revealed the following sequence types by species, K. pneumoniae: ST15 (n = 5), ST273 (n = 2), ST11, and ST29; E. coli: ST162 (n = 3), ST457, ST224, and ST1196; E. cloacae complex: ST171, ST286, ST544 and ST61. To the best of our knowledge, this is the first description of NDM-producing E. cloacae complex isolates recovered from cats. Even though different species and clones were observed, it is remarkable the finding of some major clones among K. pneumoniae and E. coli, as well as the circulation of NDM as the main carbapenemase. Surveillance in companion pets is needed to detect the spread of carbapenem-resistant Enterobacterales and to alert about the dissemination of these pathogens among pets and humans. [ABSTRACT FROM AUTHOR]

Background Emergence and dissemination of antibiotic resistance is one of the major risks associated with the rampant usage of antibiotics in food-producing animals including aquaculture. Objective To determine Epidemiological Cut-OFF (ECOFF) values of heterotrophic bacterial populations from shrimp culture environments against five different antibiotics Methods In this present study, bacterial samples were isolated from Penaeus vannamei culture environment in different locations of Andhra Pradesh, which is the aquaculture hub of India. The bacterial isolates were assessed for antibiotic resistance towards five antibiotics belonging to different classes (oxytetracycline, chloramphenicol, erythromycin, ciprofloxacin, and co-trimoxazole) by the disc diffusion method. Determination of Epidemiological Cut-OFF (ECOFF) values and analysis by employing normalized resistance interpretation (NRI) was carried out. Results The most dominant bacterial populations from shrimp culture were Vibrio spp. (pathogenic bacteria) followed by Bacillus spp. (probiotic bacteria). The bacterial isolates showed highest resistance towards oxytetracycline (overall 23.38%) and in location L6 (59.4%) followed by co-trimoxazole (31.1%). ECOFF values calculated by employing NRI showed that the disc diffusion data were distributed in a normalized manner. The maximum ECOFF value was obtained for ciprofloxacin (23.32 mm), while the minimum value was observed for oxytetracycline (9.05 mm). The antibiotic resistant phenotypes showed that the majority of the heterotrophic bacterial isolates (>60%) belonged to the non-wild type phenotype and primarily towards oxytetracycline (90%). Conclusion The presence of non-wild antibiotic-resistant phenotypes of heterotrophic bacterial populations (which include not only pathogenic bacteria but also probiotic bacteria) indicates that shrimp culture ponds may be a reservoir for drug-resistant bacteria and there is a greater risk associated with transmission of resistant genes across bacterial flora. Highlights NRI analysis of antibiotic disc diffusion data of heterotrophic bacterial populations in shrimp aquaculture environments revealed that majority of them belonged to non-wild type (90%) paticularly to oxytetracycline in comparison to other studied antibiotics (chloramphenicol, erythromycin, ciprofloxacin and co-trimoxazole). [ABSTRACT FROM AUTHOR]

Insight into the phase-dependent electron transfer kinetics and electrocatalytic activity of metal oxide nanostructures is important in the rational design of functional nanostructures for realizing high-performance electrochemical sensors. This study focuses on elucidating the effect of the crystalline phase on the electron transfer kinetics and electrocatalytic activity of iron(III) oxide. The α -FeOOH, γ -Fe2O3, and α -Fe2O3 nanorods were designed by using a simple chemical method and calcining process. The phase-dependent difference in the electron transfer kinetics and electrocatalytic activity toward the sensitive response of chloramphenicol (CAP) is observed by the transformation from α -FeOOH to γ -Fe2O3, and from α -FeOOH to α -Fe2O3 nanorods. We found that the oxygen vacancies formed in phase transformation from α -FeOOH to α -Fe2O3 is a key factor in promoting the electrochemical reduction of chloramphenicol. The α -Fe2O3 nanorods-based electrochemical sensors showed a linear response in the CAP concentration range from 0.1 to 75 μ M with a limit of detection of 60 nM and an electrochemical sensitivity of 2.86 μ A μ M−1 cm−2. This work further provides valuable physical insight into the phase-dependent electron transfer kinetics and electrocatalytic activity of metal oxide nanostructures for the rational design of sensing interface. [ABSTRACT FROM AUTHOR]

Herein, a catalytic amplification enhanced dual-signal immunochromatographic assay (ICA) based on Pt nanoparticles (Pt NPs) modified with Ti3C2Tx MXene (Ti3C2Tx@Pt) was first developed for chloramphenicol (CAP) in animal-derived foods. Due to the large specific surface area and abundant active sites of Ti3C2Tx@Pt, they can be loaded with hundreds of Pt NPs to enhance their catalytic activity, resulting in a significant increase in the detection sensitivity; the sensitivity was up to 50-fold more sensitive than the reported ICA for CAP. The LODs of the developed method for milk/chicken/fish were 0.01 μg/kg, the LOQs were 0.03 μg/kg and the recovery rates were 80.5–117.0%, 87.2–118.1% and 92.7–117.9%, with corresponding variations ranging from 3.1 to 9.6%, 6.0 to 12.7% and 6.0 to 13.6%, respectively. The linear range was 0.0125–1.0 μg/kg. The results of the LC-MS/MS confirmation test on 30 real samples had a good correlation with that of our established method (R2 > 0.98), indicating the practical reliability of the established method. The above results indicated that an ICA based on the Ti3C2Tx@Pt nanozyme has excellent potential as a food safety detection tool. [ABSTRACT FROM AUTHOR]

Enterococci are part of the natural flora of the gastrointestinal tract of mammals, including humans, birds and invertebrates. They can cause infection, mainly among hospitalized patients, as well as acquire and transfer antimicrobial resistance genes. The present study allowed the isolation of 98 Enterococcus (73.47% E. faecium, 23.47% E. faecalis, 3.06% E. avium) strains from 120-day-old healthy chickens that had never been treated with antimicrobials. Their antimicrobial resistance was evaluated by the agar disk diffusion method; high-level aminoglycoside (streptomycin and gentamicin) and vancomycin resistance were established using the microbroth dilution method. The highest percentages of resistant isolates were detected with quinupristin–dalfopristin (88.78%), rifampicin (64.29%), tetracyclines (45.92%), and enrofloxacin (41.84%). High percentages of susceptible strains were found with teicoplanin (100%), amoxicillin–clavulanic acid (97.96%), nitrofurantoin (94.90%), ampicillin (92.86%), chloramphenicol (90.82%), and linezolid (88.78%). About 60% of the strains were classified as MDR (multidrug-resistant). Moreover, PCR was carried out to investigate genes encoding for tetracyclines resistance determinants: tet(M), tet(L), tet(O), tet(K), and Int-Tn. Genes were detected in 68 (69.38%) strains: 36 were shown to be resistant with the agar disk diffusion method, while 28 were intermediate, and 2 were susceptible. The present study showed that chickens never treated with antimicrobials potentially harbor enterococci having phenotypic and genotypic characters of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

The aim of the present study was to develop and optimize a wound dressing film loaded with chloramphenicol (CAM) and ibuprofen (IBU) using a Quality by Design (QbD) approach. The two drugs have been combined in the same dressing as they address two critical aspects of the wound healing process, namely prevention of bacterial infection and reduction of inflammation and pain related to injury. Three critical formulation variables were identified, namely the ratios of Kollicoat SR 30D, polyethylene glycol 400 and polyvinyl alcohol. These variables were further considered as factors of an experimental design, and 17 formulations loaded with CAM and IBU were prepared via solvent casting. The films were characterized in terms of dimensions, mechanical properties and bioadhesion. Additionally, the optimal formulation was characterized regarding tensile properties, swelling behavior, water vapor transmission rate, surface morphology, thermal behavior, goniometry, in vitro drug release, cell viability, and antibacterial activity. The film was optimized by setting minimal values for the folding endurance, adhesive force and hardness. The optimally formulated film showed good fluid handling properties in terms of swelling behavior and water vapor transmission rate. IBU and CAM were released from the film up to 80.9% and 82.5% for 8 h. The film was nontoxic, and the antibacterial activity was prominent against Micrococcus spp. and Streptococcus pyogenes. The QbD approach was successfully implemented to develop and optimize a novel film dressing promising for the treatment of low-exuding acute wounds prone to infection and inflammation. [ABSTRACT FROM AUTHOR]

A colorimetric and photothermal dual-mode detection method based on β-NiOOH nanozyme-3,3′,5,5′-tetramethylbenzidine (TMB) system was established for chloramphenicol (CAP) content in fruit juice. Herein, a novel nanozyme β-NiOOH with high oxidase-like activity can directly and effectively catalyze the oxidation of colorless TMB to blue color TMB oxidation (oxTMB) without the presence of H2O2. Using a competition-type immunoassay, the oxTMB can induce not only an increase in the absorption peak intensity but also a photothermal effect under 808 nm laser irradiation, achieving dual-mode detection of CAP. The increase of absorbance at 652 nm and the increase of temperature generated by photothermal conversion are linearly correlated with the CAP content. Under the optimal conditions, the dual-mode detection shows a low limit of 0.0056 ng mL−1 for the colorimetric method, and 0.0016 ng mL−1 for the photothermal method. Moreover, the developed colorimetric and photothermal dual-mode immunobiosensor was successfully used to detect CAP in fruit juice with an acceptable recovery rate between 93.387% and 118.514%. This method has good repeatability, specificity, and accuracy, and provides an efficient approach for real-time detection of CAP in food safety analysis and detection platforms. [ABSTRACT FROM AUTHOR]

Overuse of antibiotics causes environmental pollution, and activated carbon adsorption is an effective way to remove antibiotics from polluted water. Herein, a cost-effective biomass carbon adsorbent for the adsorption of chloramphenicol (CHL) was prepared from pomelo peel using KHCO3 activator. The activated carbon boasted a significant specific surface area (SBET) of 1608 m2 g−1 with a maximum adsorption capacity (Qmax) for CHL reaching 549.5 mg g−1. The effect of adsorption behavior on adsorption capacity was studied. The adsorption process followed the pseudo-second-order kinetic and Langmuir models. From combined FT-IR and XPS data, the adsorption action included both physical adsorption and chemical adsorption. The rate-limiting step was diffusion through the boundary layer. The adsorption mechanism mainly included the processes of pore filling, functional group binding, and hydrogen bond and π–π interactions. Thermodynamic parameters demonstrated spontaneous and exothermic properties. This work demonstrated the rational application of waste biomass carbon for efficient adsorption of antibiotics to provide new help for antibiotic removal from polluted water. [ABSTRACT FROM AUTHOR]

Malassezia furfur is a yeast known as the etiological agent of seborrheic dermatitis. We evaluated the action of five different antimicrobials (amphotericin B, chloramphenicol, ketoconazole, fluconazole, and nystatin) on inhibiting biofilm formation and removing biofilm already formed by M. furfur. The assays were carried out using the microdilution method, and scanning electron microscopy images were used to analyze the biofilm structure. According to the results obtained, the percentage of inhibition was higher for chloramphenicol, followed by ketoconazole, nystatin, and amphotericin B. Regarding the eradication of the biofilm formed, the highest percentage was chloramphenicol, followed by ketoconazole and nystatin. Amphotericin B did not affect biofilm eradication, whereas fluconazole did not cause significant changes inhibiting or removing M. furfur biofilm. Therefore, except for fluconazole, all evaluated antimicrobials had inhibiting effects on the biofilm of M. furfur, either in its formation and/or eradication. Although the results achieved with chloramphenicol have been highlighted, further in vitro and in vivo studies are still needed in order to include this antimicrobial in the therapy of seborrheic dermatitis due to its toxicity, especially to the bone marrow. [ABSTRACT FROM AUTHOR]

This study aimed to create new composite materials based on diatomite—a non-organic porous compound—through its surface modification with bioactive organic compounds, both synthetic and natural. Chloramphenicol, tetrahydroxymethylglycoluril and betulin were used as modifying substances. Composite materials were obtained by covering the diatomite surface with bioactive substance compounds as a solution and material dispersion in it. The materials were characterized by IR spectroscopy, SEM and X-ray photoelectron spectroscopy. For the biocomposites, the hemolytic effect, plasma proteins' adsorption on the surface and the antibacterial activity of the obtained materials were studied. Results show that the obtained materials are promising for medicine and agriculture. [ABSTRACT FROM AUTHOR]