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1.
Reprod Domest Anim ; 59(8): e14699, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39104057

RESUMEN

Many of the reproductive tract infections in the bitches are caused by bacteria that can normally be present on the vaginal mucosa. These bacteria also might have an important role as the cause responsible for pregnancy loss and fetal deaths. The choice of antibiotic therapy for the pregnant animal is narrow and represents a severe problem in veterinary practice, especially due to increased antimicrobial resistance. Due to incorrect antimicrobials use in breeding kennels, the aim of the present study was to assess the occurrence of the bacterial flora isolated from the pregnant bitches and their antibiotic sensitivity. The study was carried out at the private Veterinary clinic in Novi Sad, Serbia. The vaginal swabs were taken from 60 bitches diagnosed with pregnancy and were sent to be laboratory tested. Based on the results, the most common isolated pathogens were Staphylococcus pseudintermedius (20%) and beta-hemolytic streptococci (18.33%). Furthermore, significant resistance to antibiotics from beta-lactams group was detected. It is of particular importance that antimicrobial treatment be evidence based in order to reduce the overuse of antimicrobials due to increased concern regarding antimicrobial resistance.


Asunto(s)
Antibacterianos , Enfermedades de los Perros , Farmacorresistencia Bacteriana , Staphylococcus , Vagina , Animales , Femenino , Perros , Embarazo , Vagina/microbiología , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/tratamiento farmacológico , Antibacterianos/farmacología , Staphylococcus/efectos de los fármacos , Complicaciones Infecciosas del Embarazo/veterinaria , Complicaciones Infecciosas del Embarazo/microbiología , Complicaciones Infecciosas del Embarazo/epidemiología , Prevalencia , Streptococcus/efectos de los fármacos , Streptococcus/aislamiento & purificación , Serbia/epidemiología , Pruebas de Sensibilidad Microbiana
2.
Beilstein J Org Chem ; 20: 1800-1816, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39109298

RESUMEN

Antimicrobial resistance presents a substantial threat to global public health, demanding urgent attention and action. This study focuses on lanthipeptides, ribosomally encoded peptides that display significant structural diversity and hold promising potential as antibiotics. Genome mining was employed to locate biosynthetic gene clusters (BGCs) containing class II lanthipeptide synthetases encoded by lanM genes. A phylogenetic study analyzing homologous sequences of functional LanM sequences revealed a unique evolutionary clade of 17 LanM proteins associated with 12 Clostridium bacterial genomes. In silico exploration identified nine complete BGCs, including one super-cluster containing two co-localized operons from Clostridium cellulovorans 743B, that encode for two new peptides named clostrisin and cellulosin. Each operon was heterologously expressed in Escherichia coli. Molecular weights associated with the expected post-translational modifications of the purified lanthipeptide were confirmed by MS-MS/MS analysis for cellulosin, while clostrisin was not post-translationally modified. Both peptides demonstrated antimicrobial activity against multidrug-resistant bacteria, such as a clinical strain of Staphylococcus epidermidis MIQ43 and Pseudomonas aeruginosa PA14. This is the first report of lanthipeptides from the Clostridium genus produced with its native biosynthetic machinery, as well as chemically and biologically characterized. This study showcases the immense potential of genome mining in identifying new RiPP synthetases and associated bioactive peptides.

3.
Int J Mol Sci ; 25(15)2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39125622

RESUMEN

Bacteria are known to be constantly adapting to become resistant to antibiotics. Currently, efficient antibacterial compounds are still available; however, it is only a matter of time until these compounds also become inefficient. Ribonucleases are the enzymes responsible for the maturation and degradation of RNA molecules, and many of them are essential for microbial survival. Members of the PNPase and RNase II families of exoribonucleases have been implicated in virulence in many pathogens and, as such, are valid targets for the development of new antibacterials. In this paper, we describe the use of virtual high-throughput screening (vHTS) to identify chemical compounds predicted to bind to the active sites within the known structures of RNase II and PNPase from Escherichia coli. The subsequent in vitro screening identified compounds that inhibited the activity of these exoribonucleases, with some also affecting cell viability, thereby providing proof of principle for utilizing the known structures of these enzymes in the pursuit of new antibacterials.


Asunto(s)
Antibacterianos , Inhibidores Enzimáticos , Escherichia coli , Exorribonucleasas , Antibacterianos/farmacología , Antibacterianos/química , Exorribonucleasas/antagonistas & inhibidores , Exorribonucleasas/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Dominio Catalítico , Ensayos Analíticos de Alto Rendimiento/métodos , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/antagonistas & inhibidores , Bacterias/efectos de los fármacos , Bacterias/enzimología
4.
Int J Biol Macromol ; : 134634, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39128760

RESUMEN

Bacterial resistance to antibiotics is a significant challenge that is associated with increased morbidity and mortality. Gram-negative bacteria are particularly problematic due to an outer membrane (OM). Current alternatives to antibiotics include antimicrobial peptides or proteins and multifunctional systems such as dendrimers. Antimicrobial proteins such as lysins can degrade the bacterial cell wall, whereas dendrimers can permeabilize the OM, enhancing the activity of endolysins against gram-negative bacteria. In this study, we present a three-stage action of endolysin combined with two different carbosilane (CBS) silver metallodendrimers, in which the periphery is modified with N-heterocyclic carbene (NHC) ligands coordinating a silver atom. The different NHC ligands contained hydrophobic methyl or N-donor pyridyl moieties. The effects of these endolysin/dendrimer combinations are based on OM permeabilization, peptidoglycan degradation, and reactive oxygen species production. The results showed that CBS possess a permeabilization effect (first action), significantly reduced bacterial growth at higher concentrations alone and in the presence of endolysin, increased ROS production (second action), and led to bacterial cell damage (third action). The complex formed between the CHAP domain of endolysin and a CBS silver metallodendrimer, with a triple mechanism of action, may represent an excellent alternative to other antimicrobials with only one resistance mechanism.

5.
J Microbiol Methods ; 224: 107008, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39103095

RESUMEN

Proteus mirabilis is a predominant species in cases of food poisoning associated with meat products and is also an opportunistic pathogen causing numerous infections in humans. This study aimed to differentiate P. mirabilis isolates using intergenic region polymorphism analysis (IRPA). The IRPA typing scheme was developed to amplify polymorphic fragments in intergenic regions (IGRs). The presence, absence, or size change of amplified products were identified and utilized as genetic markers for rapid differentiation of strains. A total of 75 P. mirabilis isolates were isolated from 63 fresh poultry and pork samples were subtyped using the IRPA and ERIC-PCR methods, and their antibiotic resistance profiles were tested. The majority of P. mirabilis isolates showed resistance to tetracycline (85.3%), doxycycline (93.3%), chloramphenicol (82.7%), streptomycin (92.0%), spectinomycin (80.0%), trimethoprim (97.3%); trimethoprim-sulfalleth (82.7%), and erythromycin (100.0%). In contrast, resistance rates to ceftriaxon, cefoxitin, cefepime, and cefotaxim were lower at only 17.3%, 5.3%, 6.7%, and 13.3%, respectively, among P. mirabilis isolates. Eleven loci were selected for analysis of the genetic diversity of 75 P. mirabilis isolates. A combination of 4 loci was determined as the optimal combination. The results compared to those obtained using ERIC-PCR for the same isolates. The Simpson's index of diversity was 0.999 for IRPA and 0.923 for ERIC-PCR, indicating that IRPA has a higher discriminatory power than ERIC-PCR. The concordance between IRPA and ERIC-PCR methods was low, primarily because IRPA classified isolates from the same ERIC cluster into separate clusters due to its high resolution. The IRPA method presented in this study offers a rapid, simple, reproducible, and economical approach for genotyping P. mirabilis.

6.
Neuroscience ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39127344

RESUMEN

Puberty is a sensitive developmental period during which stressors can cause lasting brain and behavioural deficits. While the acute effects of pubertal lipopolysaccharide (LPS) and antimicrobial (AMNS) treatments are known, their enduring impacts on neurodegeneration-related mechanisms and behaviours remain unclear. This study examined these effects in male and female mice. At five weeks old, mice received 200ul of either broad-spectrum antimicrobials or water through oral gavage twice daily for seven days. At six weeks of age, they received an intraperitoneal injection of either saline or LPS. Four weeks later, adult mice underwent neurodegeneration-related behavioural tests, including the rotarod, forepaw stride length, reversed grid hang, open field, and buried pellet tests. Two days after the final test, brain and ileal samples were collected. Results showed that female mice treated with both AMNS and LPS exhibited deficits in neuromuscular strength, while males treated with LPS alone showed increased anxiety-like behaviours. Males treated with AMNS alone had decreased sigma-1 receptor (S1R) expression in the cornu ammonis 1 (CA1) and dentate gyrus (DG), while females treated with both AMNS and LPS had decreased S1R expression. Additionally, males treated with either LPS or AMNS had lower glial-derived neurotrophic factor receptor alpha-1 (GFRA1) expression in the primary motor cortex (M1) than females. Mice treated with LPS alone had decreased GFRA1 expression in the DG and decreased S1R expression in the secondary motor cortex (M2). These findings suggest that pubertal AMNS and LPS treatments may lead to enduring changes in biomarkers and behaviours related to neurodegeneration.

7.
Open Forum Infect Dis ; 11(8): ofae402, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39091641

RESUMEN

Our center launched the first antimicrobial stewardship program in Peru. From 2016 to 2023, the proportion of antimicrobial prescriptions audited increased from 60% to 95%, and 65% to 95% of recommendations were accepted. Vancomycin and meropenem use dropped by 95% and 84%, respectively. The proportion of recommendations for surgical prophylaxis exceeded 90%.

8.
J Food Sci ; 2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39098814

RESUMEN

Biopolymers-based food packaging materials have drawn attention as potential candidates for substitution of petroleum-based materials. In this study, composite alginate films were developed by incorporating Zn-based antimicrobials to overcome the intrinsic disadvantages of alginates that hinder their wide applications. Antimicrobials with different morphologies (nanoplatelets, nanorods, and nanospheres) were employed to investigate the effects of antimicrobials' morphology on antibacterial, thermal, mechanical, and barrier performance of composite alginate films. Meanwhile, morphological and structural characterizations were carried out to explore the interactions between antimicrobials and alginate matrix. Results indicated that films with nanospheres exhibited superior antibacterial property, while those with one-dimensional nanorods possessed better mechanical and barrier performance. Besides, preliminary test on fresh-cut potatoes and chicken breasts indicated that the composite films showed potential in extending shelf life of foods. By incorporating antimicrobials with three different morphologies, this study provides particular insights into improving properties of composite packaging materials.

9.
J Appl Microbiol ; 135(7)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38955371

RESUMEN

AIMS: This study aimed to explore potential synergistic effects of medicinal dyes with antimicrobials against pathogens responsible for skin infections. METHODS AND RESULTS: Antimicrobial testing was conducted using minimum inhibitory concentrations and minimum bactericidal/fungicidal concentration assays. The fractional inhibitory index (ΣFIC) of combinations was calculated, and isobolograms were constructed on selected combinations. Toxicity studies were conducted using the brine-shrimp lethality assay. Combination (1:1 ratio) studies noted that 26% of dye-antibiotic combinations were synergistic against the Gram-positive strains, 15% against the Gram-negative strains, and 14% against the yeasts. The Mercurochrome: Betadine® combination noted synergy at ratios against all the Staphylococcus aureus strains with ΣFIC values ranging from 0.05 to 0.48. The combination of Gentian violet with Gentamycin noted a 15-fold decrease in toxicity, and a selectivity index of 977.50 against the Escherichia coli (DSM 22314) strain. Time-kill studies were conducted on the combinations with the highest safe selectivity index (SI) value and lowest safe SI value i.e. Gentian violet with Gentamycin and Malachite green with Neomycin. Both combinations demonstrated better antimicrobial activity in comparison to the independent values and the controls. CONCLUSION: This study highlights the potential for medicinal dye combinations as a treatment for skin infections.


Asunto(s)
Colorantes , Pruebas de Sensibilidad Microbiana , Colorantes/farmacología , Staphylococcus aureus/efectos de los fármacos , Sinergismo Farmacológico , Antiinfecciosos/farmacología , Violeta de Genciana/farmacología , Antibacterianos/farmacología , Colorantes de Rosanilina/farmacología , Escherichia coli/efectos de los fármacos
10.
Open Forum Infect Dis ; 11(7): ofae336, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38966853

RESUMEN

Background: A commonly used guideline for community-acquired pneumonia (CAP) is the joint American Thoracic Society and Infectious Diseases Society of America practice guideline. We aimed to investigate the effect of guideline-concordant therapy in the treatment of CAP. Methods: We systematically searched MEDLINE, Embase, CENTRAL, Web of Science, and Scopus from 2007 to December 2023. We screened citations, extracted data, and assessed risk of bias in duplicate. Primary outcomes were mortality rates, intensive care unit (ICU) admission, and length of stay. Secondary outcomes were guideline adherence, readmission, clinical cure rate, and adverse complications. We performed random-effect meta-analysis to estimate the overall effect size and assessed heterogeneity using the I2 statistics. Results: We included 17 observational studies and 82 240 patients, of which 10 studies were comparative and pooled in meta-analysis. Overall guideline adherence rate was 65.2%. Guideline-concordant therapy was associated with a statistically significant reduction in 30-day mortality rate (crude odds ratio [OR], 0.49 [95% confidence interval .34-.70; I2 = 60%]; adjusted OR, 0.49 [.37-.65; I2 = 52%]) and in-hospital mortality rate (crude OR, 0.63 [.43-.92]; I2 = 61%). Due to significant heterogeneity, we could not assess the effect of guideline-concordant therapy on length of stay, ICU admission, readmission, clinical cure rate, and adverse complications. Conclusions: In hospitalized patients with CAP, guideline-concordant therapy was associated with a significant reduction in mortality rate compared with nonconcordant therapy; however, there was limited evidence to support guideline-concordant therapy for other clinical outcomes. Future studies are needed to assess the clinical efficacy and safety of current guideline recommendations.

11.
Phytomedicine ; 132: 155845, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38964154

RESUMEN

BACKGROUND: Compounds of natural origin are potent source of drugs with unique mechanisms of action. Among phytochemicals, trans-cinnamaldehyde (t-CA) exhibits a wide range of biological activity, thus has been used for centuries to fight bacterial and fungal infections. However, the molecular basis of these properties has not been fully covered. Considering that difficult-to-control infections are becoming a rising global problem, there is a need to elucidate the molecular potential of t-CA. PURPOSE: To evaluate the antibacterial activity of t-CA against Shiga-toxigenic E. coli strains and elucidate its mechanism of action based on the inhibition of the virulence factor expression. METHODS: The antimicrobial potential of t-CA was assessed with two-fold microdilution and time-kill assays. Further evaluation included bioluminescence suppression assays, quantification of reactive oxygen species (ROS) and assessment of NAD+/NADH ratios. Morphological changes post t-CA exposure were examined using transmission electron microscopy. RNA sequencing and radiolabeling of nucleotides elucidated the metabolic alterations induced by t-CA. Toxin expression level was monitored through the application of fusion proteins, monitoring of bacteriophage development, and fluorescence microscopy studies. Lastly, the therapeutic efficacy in vivo was assessed using Galleria mellonella infection model. RESULTS: A comprehensive study of t-CA's bioactivity showed unique properties affecting bacterial metabolism and morphology, resulting in significant bacterial cell deformation and effective virulence inhibition. Elucidation of the underlying mechanisms indicated that t-CA activates the global regulatory system, the stringent response, manifested by its alarmone, (p)ppGpp, overproduction mediated by the RelA enzyme, thereby inhibiting bacterial proliferation. Intriguingly, t-CA effectively downregulates Shiga toxin gene expression via alarmone molecules, indicating its potential for therapeutic effect. In vivo validation demonstrated a significant improvement in larval survival rates post- t-CA treatment with 50 mg/kg (p < 0.05), akin to the efficacy observed with azithromycin, thus indicating its effectiveness against EHEC infections (p < 0.05). CONCLUSIONS: Collectively, these results reveal the robust antibacterial capabilities of t-CA, warranting its further exploration as a viable anti-infective agent.

12.
J Dairy Sci ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39004130

RESUMEN

Antimicrobial use (AMU) data are essential for monitoring usage over time, facilitating reduction strategies to combat the threat of antimicrobial resistance (AMR) to both human and animal health. The objective of this study was to measure and describe AMU over a 12-mo period in Irish dairy herds and compare 3 different recording methods to a reference method. A sample of 33 Irish dairy herds were randomly selected from 6 private veterinary practices across Ireland. The herds were followed for a 12-mo period and their AMU was monitored using 3 recording methods: 1. Veterinary prescription data (VET), 2. The inventory of medicine bins on the farms (BIN), and 3. Farmer treatment records from herd recording software (APP). Each recording method was compared with a previously developed reference method for AMU. The reference method used was based on pre- and poststudy medicine stock on the farms combined with veterinary prescription data. Antimicrobial use was analyzed using both mass- and dosed-based metrics, including mass (mg) of antimicrobial active ingredient per population correction unit (mg/PCU), defined daily doses for animals (DDDVET) and defined course doses for animals (DCDVET). Median AMU was 16.24, 10.47, 8.87 and 15.55 mg/PCU by mass, and 2.43, 1.55, 1.19 and 2.26 DDDVET by dose for VET, BIN, APP, and reference method data, respectively. Reliability of the agreement between each pair of methods was quantified using the concordance correlation coefficient (CCC). When compared with the reference method, VET data had excellent reliability [95% confidence interval (CI) of CCC: 0.992-0.998]. The BIN data had good to excellent reliability [95% CI of CCC: 0.776-0.936]. The APP data had poor reliability when compared with the reference method [95% CI of CCC: -0.167-0.156]. Our results highlight that a small number of herds were contributing most to overall use and farmers showed varying levels of consistency in recording AMU. Veterinary data were the most reliable approach for assessing AMU when compared with a reference method of AMU. This is an important finding for the future monitoring of AMU at a national level.

13.
J Vet Intern Med ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39005215

RESUMEN

BACKGROUND: Available descriptive studies on equine pneumonia are outdated or focus on specific horse or bacterial populations. OBJECTIVES: To describe the clinical presentation and bacterial isolates of adult horses with bacterial pneumonia and identify factors associated with death. ANIMALS: One hundred sixteen horses >2 years old with bacterial pneumonia. METHODS: Retrospective case series. Data regarding history, physical examination, clinicopathologic features, treatment, bacterial culture and sensitivity, and outcome were collected and analyzed retrospectively. RESULTS: Historical risk factors were present for 60% of cases, whereas abnormal vital signs on intake were present for <50%. Most horses (58%) underwent at least 1 change of antimicrobial treatment, and 67% received the highest-priority critically important antimicrobials. Streptococcus zooepidemicus was the most isolated bacteria (44%), followed by Escherichia coli (19%), Klebsiella spp. (18%), other Streptococcus species (17%), and Bacillus spp. (13%). Fusobacterium spp. were the most common anaerobic isolates (11%). Antimicrobial susceptibility varied widely. Survival to discharge was 73%. Heart rate at presentation (odds ratio [OR] 1.08, 95% confidence interval [CI] 1.008-1.17, P = .03) and higher creatinine (OR 14.1, 95% CI 1.56-127.6, P = .02) increased the risk of death. Higher lymphocyte count (OR 0.27, 95% CI 0.08-0.94, P = .04) reduced risk. CONCLUSIONS AND CLINICAL IMPORTANCE: Contrasting older literature, Fusobacterium spp. were the most common anaerobes. Streptococcus zooepidemicus remained the most common isolate and was predictably susceptible to penicillin. Antimicrobial susceptibility was otherwise variable and broad applicability is limited as this was a single-center study. Increased risk of death associated with tachycardia and abnormally high serum creatinine concentration is consistent with previous studies.

14.
Biomed Pharmacother ; 178: 117153, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39024833

RESUMEN

Infectious diseases are a major threat to global health and cause millions of deaths every year, particularly in developing countries. The emergence of multidrug resistance challenges current antimicrobial treatments, inducing uncertainty in therapeutic protocols. New compounds are therefore necessary. A drug repurposing approach could play a critical role in developing new treatments used either alone or in combination with standard therapy regimens. Herein, we focused on cysteamine, an aminothiol endogenously synthesized by human cells during the degradation of coenzyme-A, which is a drug approved for the treatment of nephropathic cystinosis. Cysteamine influences many biological processes due to the presence of the highly reactive thiol group. This review provides an overview of cysteamine-mediated effects on different viruses, bacteria and parasites, with a particular focus on infections caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), Mycobacterium tuberculosis, non-tuberculous mycobacteria (NTM), and Pseudomonas aeruginosa. Evidences for a potential use of cysteamine as a direct antimicrobial agent and/or a host-directed therapy, either alone or in combination with other antimicrobial drugs, are described.

15.
Environ Toxicol Chem ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-39031710

RESUMEN

Tire and road wear particles (TRWP) contain complex mixtures of chemicals and release them to the environment, and potential toxic effects of these chemicals still need to be characterized. We used a standardized surrogate for TRWP, cryogenically milled tire tread (CMTT), to isolate and evaluate effects of tire-associated chemicals. We examined organic chemical mixtures extracted and leached from CMTT for the toxicity endpoints genotoxicity, estrogenicity, and inhibition of bacterial luminescence. The bioassays were performed after chromatographic separation on high-performance thin-layer chromatography (HPTLC) plates. Extracts of CMTT were active in all three HPTLC bioassays with two estrogenic zones, two genotoxic zones, and two zones inhibiting bacterial luminescence. Extracts of CMTT artificially aged with thermooxidation were equally bioactive in each HPTLC bioassay. Two types of aqueous leachates of unaged CMTT, simulating either digestion by fish or contact with sediment and water, contained estrogenic chemicals and inhibitors of bacterial luminescence with similar profiles to those of CMTT extracts. Of 11 tested tire-associated chemicals, two were estrogenic, three were genotoxic, and several inhibited bacterial luminescence. 1,3-Diphenylguanidine, transformation products of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and benzothiazoles were especially implicated through comparison to HPTLC retention factors in the CMTT samples. Other bioactive bands in CMTT samples did not correspond to any target chemicals. Tire particles clearly contain and can leach complex mixtures of toxic chemicals to the environment. Although some known chemicals contribute to estrogenic, genotoxic, and antibacterial hazards, unidentified toxic chemicals are still present and deserve further investigation. Overall, our study expands the understanding of potential adverse effects from tire particles and helps improve the link between those effects and the responsible chemicals. Environ Toxicol Chem 2024;00:1-11. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

16.
Animals (Basel) ; 14(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38998001

RESUMEN

Diseases are responsible for losses in livestock production by increasing animal mortality and reducing productivity. The administration of antibiotics can help mitigate these negative effects. However, inappropriate use can lead to severe complications, such as raising antibiotic resistance. The purpose of this study was to perform a comparative analysis of antibiotic use and disease frequency over four years, based on the size of dairy farms and the type of farm. The study covered a 4-year period and included medium dairy farms (20-50 cows, n = 13), large dairy farms (>250 cows, n = 8), and large beef farms (n = 8). The collected data involved antimicrobial use but also included farm demographics, animal health, disease frequency, and herd management practices. The criteria used to categorise antibiotics into groups A-D were based on the EMA guidelines. The carried-out study showed that the large dairy cattle farms had the highest antibiotic consumption (18.29 mg·PCU-1), due to the high frequency of diseases, and consequently, the treatment of calf (diarrhoea, lung inflammations) and cow diseases (general treatment and mastitis). Cattle on large beef farms suffer mainly from general diseases caused by maintenance and herd management conditions. The use of restrict antibiotics was, in some cases, unjustified (antibiotics for dry cow therapy). Future studies should consider a larger number of farms, taking into account the given direction of cattle production.

17.
Molecules ; 29(13)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38998921

RESUMEN

The emergence of antimicrobial resistance represents a serious threat to public health and for infections due to multidrug-resistant (MDR) microorganisms, representing one of the most important causes of death worldwide. The renewal of old antimicrobials, such as colistin, has been proposed as a valuable therapeutic alternative to the emergence of the MDR microorganisms. Although colistin is well known to present several adverse toxic effects, its usage in clinical practice has been reconsidered due to its broad spectrum of activity against Gram-negative (GN) bacteria and its important role of "last resort" agent against MDR-GN. Despite the revolutionary perspective of treatment with this old antimicrobial molecule, many questions remain open regarding the emergence of novel phenotypic traits of resistance and the optimal usage of the colistin in clinical practice. In last years, several forward steps have been made in the understanding of the resistance determinants, clinical usage, and pharmacological dosage of this molecule; however, different points regarding the role of colistin in clinical practice and the optimal pharmacokinetic/pharmacodynamic targets are not yet well defined. In this review, we summarize the mode of action, the emerging resistance determinants, and its optimal administration in the treatment of infections that are difficult to treat due to MDR Gram-negative bacteria.


Asunto(s)
Antibacterianos , Colistina , Farmacorresistencia Bacteriana Múltiple , Bacterias Gramnegativas , Colistina/uso terapéutico , Colistina/farmacología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Humanos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana , Animales
18.
Microb Ecol ; 87(1): 93, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008123

RESUMEN

Huanglongbing, also known as citrus greening, is currently the most devastating citrus disease with limited success in prevention and mitigation. A promising strategy for Huanglongbing control is the use of antimicrobials fused to a carrier protein (phloem protein of 16 kDa or PP16) that targets vascular tissues. This study investigated the effects of genetically modified citrus trees expressing Citrus sinensis PP16 (CsPP16) fused to human lysozyme and ß-defensin-2 on the soil microbiome diversity using 16S amplicon analysis. The results indicated that there were no significant alterations in alpha diversity, beta diversity, phylogenetic diversity, differential abundance, or functional prediction between the antimicrobial phloem-overexpressing plants and the control group, suggesting minimal impact on microbial community structure. However, microbiota diversity analysis revealed distinct bacterial assemblages between the rhizosphere soil and root environments. This study helps to understand the ecological implications of crops expressing phloem-targeted antimicrobials for vascular disease management, with minimal impact on soil microbiota.


Asunto(s)
Bacterias , Citrus , Microbiota , Floema , Enfermedades de las Plantas , Rizosfera , Microbiología del Suelo , Floema/microbiología , Floema/metabolismo , Bacterias/genética , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Enfermedades de las Plantas/microbiología , Citrus/microbiología , Plantas Modificadas Genéticamente/microbiología , Plantas Modificadas Genéticamente/genética , Filogenia , Metagenómica , Muramidasa/metabolismo , Muramidasa/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , beta-Defensinas/genética , ARN Ribosómico 16S/genética , Antiinfecciosos/farmacología , Antiinfecciosos/metabolismo , Citrus sinensis/microbiología , Raíces de Plantas/microbiología
19.
Bioanalysis ; : 1-9, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39072476

RESUMEN

Aim: Pharmacokinetic studies in children are limited, in part due to challenges in blood sampling. We compare the use of capillary microsampling and conventional sampling techniques in pediatric patients to show results that can be used in the pharmacokinetic analysis of Cefazolin. Patients & Methods: Paired blood samples (n = 48) were collected from 12 patients (median age/weight 49 months/18 kg). Results: The United States Federal Drug Administration incurred sample reanalysis acceptance criteria was used and identified 79% of paired samples achieved a difference of less than 20% in magnitude with a capillary microsampling bias of -10% (SD 20%). With exclusion of PK outliers, this rose to 88%. Conclusion: Capillary microsampling is reliable, meets acceptance criteria and can be used in pharmacokinetic studies.ACTRN: 12618001469202.


What is this article about? This study assesses a novel method of blood sample collection (capillary microsampling) for the analysis of a common antibiotic, cefazolin. In this study, we compare the results from samples collected using this method to blood tests taken in the traditional way.Capillary microsampling collects a very small volume of blood (about a drop of blood or 0.05 ml) taken from a skin prick and collected in a capillary tube. Traditional blood sampling collects a larger volume of blood (typically from 1 to 3 ml) taken from an artery or a vein. In this study, the patients (10 male and 2 female) had a mean age of 49 months and a mean weight of 18 kg. The amount of cefazolin in the blood samples were analyzed using the same methodology and results compared with assess the variability and reliability of the capillary microsampling method.What were the results? The results showed that difference of the two sample types is within the accepted criteria of the United States Federal Drug Administration and the European Medicines Agency, meaning the results are reliable.What do the results of the study mean? Blood samples for cefazolin can be small and easily obtained from a skin prick as a capillary microsample and can give reliable results. This greatly aids the ability to study the metabolism of cefazolin in children, particularly those that are not able to give a large amount of blood.

20.
Microorganisms ; 12(7)2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39065268

RESUMEN

Hydraulic fracturing, or fracking, requires large amounts of water to extract fossil fuel from rock formations. As a result of hydraulic fracturing, the briny wastewater, often termed back-produced fracturing or fracking water (FW), is pumped into holding ponds. One of the biggest challenges with produced water management is controlling microbial activity that could reduce the pond water's reusable layer and pose a significant environmental hazard. This study focuses on the characterization of back-produced water that has been hydraulically fractured using chemical and biological analysis and the development of a high-throughput screening method to evaluate and predict the antimicrobial effect of four naturally and commercially available acidic inhibitors (edetic acid, boric acid, tannic acid, and lactic acid) on the growth of the FW microbiome. Liquid cultures and biofilms of two laboratory model strains, the vegetative Escherichia coli MG1655, and the spore-forming Bacillus atrophaeus (also known as Bacillus globigii, BG) bacteria, were used as reference microorganisms. Planktonic bacteria in FW were more sensitive to antimicrobials than sessile bacteria in biofilms. Spore-forming BG bacteria exhibited more sensitivity to acidic inhibitors than the vegetative E. coli cells. Organic acids were the most effective bacterial growth inhibitors in liquid culture and biofilm.

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