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1.
J Environ Manage ; 370: 122571, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39307088

RESUMEN

During the Covid-19 pandemic and its aftermath, there has been a sudden surge in the production and consumption of macrolide antibiotics. This surge has had a significant impact on water quality, leading to concentrations exceeding acceptable limits. To address this concerning issue, a magnetic graphene oxide-zinc oxide nanocomposite (MZG) was synthesized using a straightforward wet chemical synthesis method. The synthesized catalyst was then subjected to comprehensive characterization using sophisticated techniques including HRTEM, XRD, FTIR, Raman spectroscopy, BET, XPS, VSM, DRS, and TGA. Subsequently, the MZG photocatalyst's efficacy was evaluated through a series of experiments aimed at degrading azithromycin drug residues in water. These techniques divulged substantial information about the morphology, polycrystallinity, size (in nm range), functional groups, defects, surface area (132.9 m2/g), elemental composition (C, O, Fe and Zn), super paramagnetism (Ms 69.78 emu/g), suitable bandgap (2.8 eV) and thermal stability of the material, respectively. The optimized concentration of MZG photocatalyst demonstrated remarkable potential for photocatalytic degradation, particularly towards higher concentrations of 50 ppm azithromycin. It achieved an impressive degradation efficiency of 96.04 % in water when exposed to normal sunlight for just 1 h. Kinetic studies revealed a first-order reaction rate, with a notably higher rate constant (k = 0.0533 min⁻1) compared to other photocatalysts. Furthermore, MZG had shown better recyclabilty up to four cycles with minimal loss of photocatalytic acitvity to only 9%. Thus, it proves to be both effective and cost-efficient, capable of functioning under visible radiation. This makes it suitable for industrial applications aimed at removing azithromycin drugs and promoting a safer and more sustainable environment.

2.
Microorganisms ; 12(9)2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39338480

RESUMEN

A resurgence of Mycoplasma pneumoniae (MP)-the leading cause of community-acquired bacterial pneumonia, particularly in children-occurred following the COVID-19 pandemic. We aimed to investigate the clinical manifestations, macrolide resistance patterns, and therapeutic approaches related to the MP pneumonia epidemic. Children and adolescents diagnosed with MP pneumonia in September-December 2023 were screened. Clinical data were retrospectively collected from 13 major hospitals using concordant microbiological criteria, including either a positive PCR result or four-fold increase in serological markers. Demographic characteristics, treatment modalities, and clinical outcomes were analyzed. Of the 474 screened patients, 374 (median age: 7.7 [IQR, 5.4-9.6] years; hospitalization rate: 88.6%) met the microbiological confirmation criteria. Most patients experienced fever (98.9%), and lobular/lobar consolidation (59.1%) was the dominant radiological finding. The macrolide resistance rate remained high at 87.0%; corticosteroids were widely used (55.6%) alongside macrolides, despite resistance. Patients with consolidation had prolonged fever (median 8 vs. 7 days, p = 0.020) and higher hospitalization rates (92.3% vs. 83.0%, p = 0.008). Macrolide resistance did not significantly influence radiological outcomes. This study highlights the ongoing challenge of macrolide resistance in MP pneumonia and need for tailored therapeutic approaches. Despite high resistance, macrolides remain commonly prescribed, often concurrently with corticosteroids.

3.
Infect Drug Resist ; 17: 3715-3722, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39221186

RESUMEN

Published data on the molecular mechanisms underlying antimicrobial resistance in Group B Streptococcus (GBS) isolates from Saudi Arabia are lacking. Here, we aimed to determine the genetic basis of resistance to relevant antibiotics in a collection of GBS clinical isolates (n = 204) recovered from colonized adults or infected patients and expressing serotypes Ia, Ib, II, III, V, and VI. Initial susceptibility testing revealed resistance to tetracycline (76.47%, n = 156/204), erythromycin (36.76%, n = 75/204), clindamycin (25.49%, n = 52/204), levofloxacin (6.37%, n = 13/204), and gentamicin (2.45%, n = 5/204). Primers designed for the detection of known resistance determinants in GBS identified the presence of erm(A), erm(B), mef(A), and/or lsa(C) genes at the origin of resistance to macrolides and/or clindamycin. Of these, erm(B) and erm(A) were associated with the cMLSB (n = 46) and iMLSB (n = 28) phenotypes, respectively, while mef(A) was linked to the M phenotype (n = 1) and lsa(C) was present in isolates with the L phenotype (n = 8). Resistance to tetracycline was mainly mediated by tet(M) alone (n = 112) or in combination with tet(O) (n = 10); the remaining isolates carried tet(O) (n = 29), tet(L) (n = 2), or both (n = 3). Isolates resistant to gentamicin (n = 5) carried aac(6')-Ie-aph(2')-Ia, and those exhibiting resistance to levofloxacin (n = 13) had alterations in GyrA and/or ParC. Most isolates with the erm gene (93.24%, n = 69/74) also had the tet gene and were therefore resistant to erythromycin, clindamycin, and tetracycline. Overall, there were no clear associations between serotypes and resistance genotypes except for the presence of erm(B) in serotype Ib isolates. Dissemination of antibiotic resistance genes across different serotypes represents a public health concern that requires further surveillance and appropriate antibiotic use in clinical practice.

4.
J Glob Antimicrob Resist ; 38: 368-375, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39117142

RESUMEN

BACKGROUND: Macrolides inhibit the growth of bacterial cells by preventing the elongation of polypeptides during protein biosynthesis and include natural, synthetic, and semi-synthetic products. Elongation prevention occurs by blocking the passage of the polypeptide chain as the macrolides bind at the nascent peptide exit tunnel. OBJECTIVE: Recent data of ribosome profiling via ribo-seq further proves that, other than blocking the polypeptide chain, macrolides are also able to affect the synthesis of individual proteins. Thus, this shows that the mode of action of macrolides is more complex than we initially thought. Since the discovery of macrolides in the 1950s, they have been widely used in veterinary practice, agriculture, and medicine. Due to misuse and overuse of antibiotics, bacteria have acquired resistance against them. Hence, it is of utmost importance for us to fully understand the mode of action of macrolides as well as the mechanisms of resistance against macrolides in order to mitigate antibiotic-resistance issues. RESULTS: Chemical modifications can be performed to improve macrolide potency if we have a better understanding of their mode of action. Furthermore, a complete and detailed understanding of the mode of action of macrolides has remained vague, as new findings have challenged theories that are already in existence-due to this obscurity, research into macrolide modes of action continues to this day. CONCLUSION: In this review, we present an overview of macrolide antibiotics, with an emphasis on the latest knowledge regarding the mode of action of macrolides as well as the mechanisms of resistance employed by bacteria against macrolides.


Asunto(s)
Antibacterianos , Bacterias , Farmacorresistencia Bacteriana , Macrólidos , Macrólidos/farmacología , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/genética , Humanos , Ribosomas/efectos de los fármacos , Ribosomas/metabolismo , Biosíntesis de Proteínas/efectos de los fármacos
6.
Biomedica ; 44(2): 182-190, 2024 05 30.
Artículo en Inglés, Español | MEDLINE | ID: mdl-39088528

RESUMEN

Introduction: The Mycobacterium chelonae species and the M. avium and M. abscessus complexes are emerging pathogens that cause mycobacteriosis. Treatment depends on the species and subspecies identified. The drugs of choice are macrolides and aminoglycosides. However, due to the resistance identified to these drugs, determining the microbe's sensitivity profile will allow clinicians to improve the understanding of the prognosis and evolution of these pathologies. Objective: To describe the macrolide and aminoglycoside susceptibility profile of cultures identified by Colombia's Laboratorio Nacional de Referencia de Mycobacteria from 2018 to 2022, as Mycobacterium avium complex, M. abscessus complex, and M. chelonae. Materials and methods. This descriptive study exposes the susceptibility profile to macrolides and aminoglycosides of cultures identified as M. avium complex, M. abscessus complex, and M. chelonae using the GenoType® NTM-DR method. Materials and methods: This descriptive study exposes the susceptibility profile to macrolides and aminoglycosides of cultures identified as M. avium complex, M. abscessus complex, and M. chelonae using the GenoType® NTM-DR method. Results: We identified 159 (47.3 %) cultures as M. avium complex, of which 154 (96.9 %) were sensitive to macrolides, and 5 (3.1 %) were resistant; all were sensitive to aminoglycosides. From the 125 (37.2 %) cultures identified as M. abscessus complex, 68 (54.4 %) were sensitive to macrolides, 57 (45.6 %) were resistant to aminoglycosides, and just one (0.8 %) showed resistance to aminoglycosides. The 52 cultures (15.5 %) identified as M. chelonae were sensitive to macrolides and aminoglycosides. Conclusions: The three studied species of mycobacteria have the least resistance to Amikacin. Subspecies identification and their susceptibility profiles allow the establishment of appropriate treatment schemes, especially against M. abscessus.


Introducción. Mycobacterium chelonae y los complejos Mycobacterium avium y M. abscessus, son agentes patógenos emergentes causantes de micobacteriosis. El tratamiento de esta infección depende de la especie y la subespecie identificadas. Los fármacos de elección son los macrólidos y aminoglucósidos, contra los cuales se ha reportado resistencia; por esta razón, el determinar el perfil de sensibilidad le permite al médico tratante comprender mejor el pronóstico y la evolución de estas infecciones. Objetivo. Describir los perfiles de sensibilidad ante macrólidos y aminoglucósidos, de los cultivos identificados como complejo Mycobacterium avium, complejo M. abscessus o especie M. chelonae, en el Laboratorio Nacional de Referencia de Micobacterias durante los años 2018 a 2022. Materiales y métodos. Se llevó a cabo un estudio descriptivo del perfil de sensibilidad a macrólidos y aminoglucósidos, de los cultivos identificados como complejo M. avium, complejo M. abscessus o M. chelonae, mediante la metodología GenoType® NTM-DR. Resultados. Los cultivos del complejo M. avium fueron 159 (47,3 %), de los cuales, 154 (96,9 %) fueron sensibles y 5 (3,1 %) resistentes a los macrólidos; todos fueron sensibles a los aminoglucósidos. Del complejo M. abscessus se estudiaron 125 (37,2 %) cultivos, 68 (54,4 %) resultaron sensibles y 57 (45,6 %) resistentes a los macrólidos; solo un cultivo (0,8 %) fue resistente a los aminoglucósidos. De M. chelonae se analizaron 52 cultivos (15,5 %), todos sensibles a los macrólidos y aminoglucósidos. Conclusiones. En las tres especies de micobacterias estudiadas, la resistencia contra la amikacina fue la menos frecuente. La identificación de las subespecies y los perfiles de sensibilidad permiten instaurar esquemas de tratamiento adecuados, especialmente en las micobacteriosis causadas por M. abscessus.


Asunto(s)
Aminoglicósidos , Macrólidos , Pruebas de Sensibilidad Microbiana , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium abscessus , Complejo Mycobacterium avium , Mycobacterium chelonae , Macrólidos/farmacología , Mycobacterium abscessus/efectos de los fármacos , Mycobacterium abscessus/genética , Mycobacterium abscessus/aislamiento & purificación , Colombia/epidemiología , Mycobacterium chelonae/efectos de los fármacos , Mycobacterium chelonae/genética , Mycobacterium chelonae/aislamiento & purificación , Aminoglicósidos/farmacología , Humanos , Complejo Mycobacterium avium/efectos de los fármacos , Complejo Mycobacterium avium/genética , Complejo Mycobacterium avium/aislamiento & purificación , Infecciones por Mycobacterium no Tuberculosas/microbiología , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Prevalencia , Farmacorresistencia Bacteriana Múltiple
9.
North Clin Istanb ; 11(3): 214-218, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39005748

RESUMEN

OBJECTIVE: Legionella pneumophila (Lp) is aerobic, non-spore forming Gram-negative bacteria, which is ubiquitous in freshwater habitats, such as rivers and hot springs, as well as colonizing artificial aquatic environments. The ability of Lp to grow intracellularly within pulmonary macrophages is a prerequisite for the development of infection. Therefore, macrolides can achieve appropriate therapeutic concentrations in eukaryotic cells, such as azithromycin. This study aimed to investigate the macrolides susceptibility of Lp. METHODS: Pre-flash water samples (n=143) were collected from the public buildings (hospitals and hotels) water system in Istanbul. Colonies were confirmed as Lp ST1, ST2-14, and non-pneumophila Lp using latex agglutination kit. RESULTS: 30 Lp were detected in hospital (n=23) and hotel (n=7) water systems using latex agglutination. Regardless of serotype and excluding strains without zone formation (≥256 mg/L), the main MIC values of azithromycin, erythromycin and clarithromycin were 0.61 mg/L (range 0.047-1 mg/L), 0.47 mg/L (range 0.047-1 mg/L) and 0.44 mg/L (range 0.047-1 mg/L), respectively. The MIC50 and MIC90 values for macrolides were 0.5 and 3 mg/L for azithromycin, respectively; 0.38 and 1 mg/L for erythromycin, respectively; and 0.5 and 1 mg/L for clarithromycin, respectively. We compared the MIC values of the strains for all antimicrobial agents tested without serotype discrimination. We did not find a significant difference between the MIC values of the antibiotics (p=0.16). CONCLUSION: Although the data obtained from our study do not fully reflect the breakpoints, further epidemiological studies are needed to standardize MIC values.

10.
Microorganisms ; 12(6)2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38930567

RESUMEN

Antibiotics are routinely added to ornamental fish tanks for treating bacterial infection or as a prophylactic measure. However, the overuse or subtherapeutical application of antibiotics could potentially facilitate the selection of antibiotic resistance in bacteria, yet no studies have investigated antibiotic use in the retail ornamental fish sector and its impact on microbial communities. The present study analyzed the concentrations of twenty antibiotics in the carriage water (which also originates from fish tanks in retail shops) collected monthly from ten local ornamental fish shops over a duration of three months. The antibiotic concentrations were correlated with the sequenced microbial community composition, and the risk of resistance selection in bacteria was assessed. Results revealed that the detected concentrations of tetracyclines were the highest among samples, followed by fluoroquinolones and macrolides. The concentrations of oxytetracycline (44.3 to 2,262,064.2 ng L-1) detected across three months demonstrated a high risk for resistance selection at most of the sampled shops. Zoonotic pathogens (species of Rhodococcus, Legionella, and Citrobacter) were positively correlated with the concentrations of oxytetracycline, tetracycline, chlortetracycline, and enrofloxacin. This suggests that antibiotic use in retail shops may increase the likelihood of selecting for zoonotic pathogens. These findings shed light on the potential for ornamental fish retail shops to create a favorable environment for the selection of pathogens with antibiotics, thereby highlighting the urgent need for enhanced antibiotic stewardship within the industry.

11.
Rev Esp Quimioter ; 37(4): 299-322, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38840420

RESUMEN

Antimicrobial agents are widely used, and drug interactions are challenging due to increased risk of adverse effects or reduced efficacy. Among the interactions, the most important are those affecting metabolism, although those involving drug transporters are becoming increasingly known. To make clinical decisions, it is key to know the intensity of the interaction, as well as its duration and time-dependent recovery after discontinuation of the causative agents. It is not only important to be aware of all patient treatments, but also of supplements and natural medications that may also interact. Although they can have serious consequences, most interactions can be adequately managed with a good understanding of them. Especially in patients with polipharmacy it is compulsory to check them with an electronic clinical decision support database. This article aims to conduct a narrative review focusing on the major clinically significant pharmacokinetic drug-drug interactions that can be seen in patients receiving treatment for bacterial infections.


Asunto(s)
Antibacterianos , Interacciones Farmacológicas , Humanos , Antibacterianos/farmacocinética , Antibacterianos/uso terapéutico , Antibacterianos/efectos adversos , Infecciones Bacterianas/tratamiento farmacológico
12.
Methods Mol Biol ; 2815: 73-78, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38884911

RESUMEN

Globally, the main molecular trials being developed to study the genetic determinants responsible for conferring resistance to bacterial organisms are amplification-based methods, hybridization-based methods, and sequence-based methods. In the specific case of Streptococcus suis, polymerase chain reaction is the only test tuned up until now for detecting resistant clinical isolates to macrolides and/or tetracyclines, the two main groups of antibiotics being ineffective against this human and animal pathogen.


Asunto(s)
Antibacterianos , Macrólidos , Reacción en Cadena de la Polimerasa , Macrólidos/farmacología , Reacción en Cadena de la Polimerasa/métodos , Humanos , Antibacterianos/farmacología , Tetraciclina/farmacología , Farmacorresistencia Bacteriana/genética , Animales , ADN Bacteriano/genética , Pruebas de Sensibilidad Microbiana/métodos
13.
Appl Environ Microbiol ; 90(7): e0050224, 2024 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-38864630

RESUMEN

Mannheimia haemolytica is a major contributor to bovine respiratory disease (BRD), which causes substantial economic losses to the beef industry, and there is an urgent need for rapid and accurate diagnostic tests to provide evidence for treatment decisions and support antimicrobial stewardship. Diagnostic sequencing can provide information about antimicrobial resistance genes in M. haemolytica more rapidly than conventional diagnostics. Realizing the full potential of diagnostic sequencing requires a comprehensive understanding of the genetic markers of antimicrobial resistance. We identified genetic markers of resistance in M. haemolytica to macrolide class antibiotics commonly used for control of BRD. Genome sequences were determined for 99 M. haemolytica isolates with six different susceptibility phenotypes collected over 2 years from a feedlot in Saskatchewan, Canada. Known macrolide resistance genes estT, msr(E), and mph(E) were identified in most resistant isolates within predicted integrative and conjugative elements (ICEs). ICE sequences lacking antibiotic resistance genes were detected in 10 of 47 susceptible isolates. No resistance-associated polymorphisms were detected in ribosomal RNA genes, although previously unreported mutations in the L22 and L23 ribosomal proteins were identified in 12 and 27 resistant isolates, respectively. Pangenome analysis led to the identification of 79 genes associated with resistance to gamithromycin, of which 95% (75 of 79) had no functional annotation. Most of the observed phenotypic resistance was explained by previously identified antibiotic resistance genes, although resistance to the macrolides gamithromycin and tulathromycin was not explained in 39 of 47 isolates, demonstrating the need for continued surveillance for novel determinants of macrolide resistance.IMPORTANCEBovine respiratory disease is the costliest disease of beef cattle in North America and the most common reason for injectable antibiotic use in beef cattle. Metagenomic sequencing offers the potential to make economically significant reductions in turnaround time for diagnostic information for evidence-based selection of antibiotics for use in the feedlot. The success of diagnostic sequencing depends on a comprehensive catalog of antimicrobial resistance genes and other genome features associated with reduced susceptibility. We analyzed the genome sequences of isolates of Mannheimia haemolytica, a major bovine respiratory disease pathogen, and identified both previously known and novel genes associated with reduced susceptibility to macrolide class antimicrobials. These findings reinforce the need for ongoing surveillance for markers of antimicrobial resistance to support improved diagnostics and antimicrobial stewardship.


Asunto(s)
Antibacterianos , Macrólidos , Mannheimia haemolytica , Macrólidos/farmacología , Saskatchewan , Antibacterianos/farmacología , Mannheimia haemolytica/efectos de los fármacos , Mannheimia haemolytica/genética , Animales , Bovinos , Marcadores Genéticos , Farmacorresistencia Bacteriana/genética , Pruebas de Sensibilidad Microbiana , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/tratamiento farmacológico
14.
Angew Chem Int Ed Engl ; 63(36): e202408725, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-38864359

RESUMEN

The strasseriolide macrolides show promising in vitro and in vivo activities against P. falciparum and T. cruzi, the parasites causing malaria and Chagas disease, respectively. However, the as yet poor understanding of structure/activity relationships and the fact that one family member proved systemically toxic for unknown reasons render a more detailed assessment of these potential lead compounds difficult. To help overcome these issues, a collective total synthesis was devised. The key steps consisted of a ring closing alkyne metathesis (RCAM) reaction to forge a common macrocyclic intermediate followed by a hydroxy-directed ruthenium catalyzed trans-hydrostannation of the propargyl alcohol site thus formed. The resulting alkenyltin derivative served as the central node of the synthesis blueprint, which could be elaborated into the natural products themselves as well as into a set of non-natural analogues according to the concept of diverted total synthesis. The recorded biological data confirmed the potency of the compounds and showed the lack of any noticeable cytotoxicity. The "northern" allylic alcohol subunit was recognized as an integral part of the pharmacophore, yet it provides opportunities for chemical modification.


Asunto(s)
Macrólidos , Plasmodium falciparum , Trypanosoma cruzi , Macrólidos/farmacología , Macrólidos/síntesis química , Macrólidos/química , Plasmodium falciparum/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos , Relación Estructura-Actividad , Antimaláricos/farmacología , Antimaláricos/síntesis química , Antimaláricos/química , Tripanocidas/farmacología , Tripanocidas/síntesis química , Tripanocidas/química , Humanos , Pruebas de Sensibilidad Parasitaria
15.
Antibiotics (Basel) ; 13(5)2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38786137

RESUMEN

Microplastics (MPs) and antibiotics are emerging pollutants widely found in aquatic environments, potentially causing environmental harm. MPs may act as carriers for antibiotics, affecting their environmental distribution. This study investigates the adsorption of four macrolide antibiotics and a metabolite onto two types of MPs: polyethylene terephthalate (PET) and polyethylene (PE). Results revealed a linear isotherm adsorption model, with higher adsorption to PET than to PE (R2 > 0.936 for PE and R2 > 0.910 for PET). Hydrophobic interactions and hydrogen bonding could be the main adsorption mechanisms, with pore filling potentially involved. Reduced particle size enhances adsorption due to the increase of active adsorption sites. This increasement is more pronounced in PE than in PET, leading to an 11.6% increase in the average adsorption of all macrolides to PE, compared to only 5.1% to PET. Dissolved organic matter inhibits adsorption (azithromycin adsorption to PE was reduced from 12% to 5.1%), while salinity enhances it just until 1% salinity. pH slightly influences adsorption, with maximal adsorption at neutral pH. Results in real samples showed that complexity of the matrix decreased adsorption. Overall, these findings indicate that PE and PET MPs can be a vector of macrolides in aquatic environments.

16.
Vet J ; 305: 106130, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38734403

RESUMEN

Tildipirosin is a macrolide antimicrobial. It is authorised for the treatment and prevention of respiratory disease in cattle and pigs. There are no data on its administration in crocodiles. Therefore, this study evaluated the disposition kinetics of tildipirosin after intravenous (dose: 2 mg/kg) and intramuscular (doses: 2 and 4 mg/kg) administration in two crocodilian species (estuarine and freshwater; n = 5). Tildipirosin plasma concentrations were quantified by a validated HPLC method. Plasma concentrations obtained at each extraction time were analysed by non-compartmental methods. In the estuarine and freshwater crocodiles, the apparent volumes of distribution of tildipirosin after intravenous administration were 0.36 ± 0.10 and 1.48 ± 0.26 L/kg, respectively. These values, suggesting poorer tissue distribution, were much lower than those obtained in mammals. There was complete bioavailability of tildipirosin after intramuscular route at a dose of 2 mg/kg; however, at a dose of 4 mg/kg the bioavailability decreased by about 20-25 %. Furthermore, the pharmacokinetics of tildipirosin were markedly different in the two crocodilian species. Considering a MIC of 0.5 µg/mL, the surrogate marker AUC0-24/MIC indicates that tildipirosin would greatly exceed the value of 65 h for both crocodile species and dose levels tested. This suggests that both doses (2 and 4 mg/kg) may provide a bactericidal effect. Therefore, based on the absence of adverse reactions following the administration of tildipirosin in both crocodilian species, and considering its favourable pharmacokinetic properties, tildipirosin may be useful in treating infections in these reptiles.


Asunto(s)
Caimanes y Cocodrilos , Tilosina , Animales , Tilosina/análogos & derivados , Tilosina/farmacocinética , Tilosina/administración & dosificación , Inyecciones Intramusculares/veterinaria , Antibacterianos/farmacocinética , Antibacterianos/administración & dosificación , Inyecciones Intravenosas/veterinaria , Agua Dulce , Semivida , Disponibilidad Biológica , Área Bajo la Curva
17.
ACS Infect Dis ; 10(6): 2183-2195, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38695481

RESUMEN

Chemicals bacteria encounter at the infection site could shape their stress and antibiotic responses; such effects are typically undetected under standard lab conditions. Polyamines are small molecules typically overproduced by the host during infection and have been shown to alter bacterial stress responses. We sought to determine the effect of polyamines on the antibiotic response of Klebsiella pneumoniae, a Gram-negative priority pathogen. Interestingly, putrescine and other natural polyamines sensitized K. pneumoniae to azithromycin, a macrolide protein translation inhibitor typically used for Gram-positive bacteria. This synergy was further potentiated in the physiological buffer, bicarbonate. Chemical genomic screens suggested a dual mechanism, whereby putrescine acts at the membrane and ribosome levels. Putrescine permeabilized the outer membrane of K. pneumoniae (NPN and ß-lactamase assays) and the inner membrane (Escherichia coli ß-galactosidase assays). Chemically and genetically perturbing membranes led to a loss of putrescine-azithromycin synergy. Putrescine also inhibited protein synthesis in an E. coli-derived cell-free protein expression assay simultaneously monitoring transcription and translation. Profiling the putrescine-azithromycin synergy against a combinatorial array of antibiotics targeting various ribosomal sites suggested that putrescine acts as tetracyclines targeting the 30S ribosomal acceptor site. Next, exploiting the natural polyamine-azithromycin synergy, we screened a polyamine analogue library for azithromycin adjuvants, discovering four azithromycin synergists with activity starting from the low micromolar range and mechanisms similar to putrescine. This work sheds light on the bacterial antibiotic responses under conditions more reflective of those at the infection site and provides a new strategy to extend the macrolide spectrum to drug-resistant K. pneumoniae.


Asunto(s)
Antibacterianos , Azitromicina , Sinergismo Farmacológico , Klebsiella pneumoniae , Macrólidos , Pruebas de Sensibilidad Microbiana , Poliaminas , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Antibacterianos/farmacología , Azitromicina/farmacología , Poliaminas/farmacología , Poliaminas/metabolismo , Macrólidos/farmacología , Putrescina/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Biosíntesis de Proteínas/efectos de los fármacos
18.
Expert Rev Anti Infect Ther ; 22(6): 373-377, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38781483

RESUMEN

INTRODUCTION: Neonatal ocular prophylaxis with 0.5% erythromycin ophthalmic ointment is mandated by law in many U.S. states despite its lack of efficacy in preventing chlamydial ophthalmia and the low incidence of gonococcal ophthalmia today. The current shortage of 0.5% erythromycin ophthalmic ointment is bringing into question what alternatives exist for neonatal ocular prophylaxis for the prevention of gonococcal ophthalmia. Providers in states with mandates are concerned with the implications of administering intramuscular ceftriaxone to every newborn. Azithromycin eye drops are being considered as an alternative. AREAS COVERED: This article discusses 1% azithromycin eye drops as an alternative to 0.5% erythromycin ophthalmic ointment. Clinical experience, side effects, resistance, logistics, pharmacokinetics, and pharmacodynamics are considered. EXPERT OPINION: Azithromycin eye drops are not an appropriate alternative to 0.5% erythromycin ophthalmic ointment for ocular prophylaxis. Prenatal screening and treatment of pregnant women is the most effective way to prevent neonatal ophthalmia. Mandates for universal prophylaxis should be withdrawn to avoid unnecessary medication administration, healthcare costs, and potential harm.


Asunto(s)
Antibacterianos , Azitromicina , Eritromicina , Gonorrea , Oftalmía Neonatal , Soluciones Oftálmicas , Humanos , Azitromicina/administración & dosificación , Azitromicina/farmacocinética , Soluciones Oftálmicas/administración & dosificación , Antibacterianos/administración & dosificación , Estados Unidos , Gonorrea/tratamiento farmacológico , Gonorrea/prevención & control , Recién Nacido , Femenino , Oftalmía Neonatal/prevención & control , Oftalmía Neonatal/tratamiento farmacológico , Embarazo , Eritromicina/administración & dosificación , Profilaxis Antibiótica/métodos , Neisseria gonorrhoeae/efectos de los fármacos
19.
J Clin Pharmacol ; 64(10): 1288-1294, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38804820

RESUMEN

Previous studies evaluating the risk of spontaneous abortions following exposure to macrolides reported controversial results. The goal of the current study was to examine the risk for spontaneous abortions following exposure to macrolides during pregnancy. We conducted a population-based retrospective cohort study by linking three computerized databases: Clalit Health Services drug dispensation database, Soroka Medical Center (SMC) birth database, and SMC hospitalizations database. Multivariate time-varying Cox regressions were performed and adjusted for suspected confounders and known risk factors for spontaneous abortions. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated. A secondary analysis was performed to assess the association between exposure to macrolides in terms of the defined daily dose dispensed and spontaneous abortions. The study cohort included 65,457 pregnancies that ended at Soroka Medical Center between 2004 and 2009, of which 6508 (9.9%) resulted in a spontaneous abortion. A total of 825 (1.26%) pregnancies were exposed to macrolides during the exposure period. Exposure to macrolides was not associated with spontaneous abortions as a group (adjusted HR 1.00 95% CI 0.77-1.31) or as specific medications. There was no evidence of a dose-response relationship between exposure to macrolides and spontaneous abortions. In conclusion, this population-based retrospective cohort study did not detect an increased risk for spontaneous abortion following exposure to macrolides during the first trimester of pregnancy.


Asunto(s)
Aborto Espontáneo , Antibacterianos , Macrólidos , Humanos , Femenino , Embarazo , Estudios Retrospectivos , Macrólidos/efectos adversos , Aborto Espontáneo/epidemiología , Aborto Espontáneo/inducido químicamente , Adulto , Antibacterianos/efectos adversos , Adulto Joven , Estudios de Cohortes , Factores de Riesgo , Bases de Datos Factuales
20.
Int J STD AIDS ; 35(10): 831-835, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38748748

RESUMEN

In recent years, there has been an increase in Neisseria gonorrhoeae infections in Europe and Spain. Disseminated gonococcal infection is an uncommon clinical presentation that includes gonococcal arthritis. Improved antibiotic treatment has reduced the incidence of gonococcal arthritis. However, the increase in gonococcal infections may have increased the frequency of this clinical entity in recent times. We report five cases of gonococcal arthritis in patients in a tertiary-care hospital in the northern area of Madrid (Spain) from October 2022 to October 2023. Major cases occurred in male patients with unprotected sex and polyarticular symptoms requiring hospital admission and treatment with ceftriaxone and cefixime. The use of molecular techniques has allowed the detection of a greater number of culture-negative cases of gonococcal arthritis, as well as the detection of mutations associated with resistance to fluoroquinolone for switching to oral treatment.


Asunto(s)
Antibacterianos , Artritis Infecciosa , Ceftriaxona , Gonorrea , Neisseria gonorrhoeae , Humanos , Antibacterianos/uso terapéutico , Artritis Infecciosa/microbiología , Artritis Infecciosa/epidemiología , Artritis Infecciosa/tratamiento farmacológico , Artritis Infecciosa/diagnóstico , Cefixima/uso terapéutico , Ceftriaxona/uso terapéutico , Farmacorresistencia Bacteriana , Gonorrea/tratamiento farmacológico , Gonorrea/epidemiología , Gonorrea/diagnóstico , Gonorrea/microbiología , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/efectos de los fármacos , Neisseria gonorrhoeae/aislamiento & purificación , España/epidemiología , Resultado del Tratamiento
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