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1.
Braz J Vet Med ; 46: e002624, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39104804

RESUMO

The use of antimicrobials in the dairy production environment for mastitis control must take etiology, clinical signs, economic impacts, and regulatory frameworks into consideration. The objective of the present review is to highlight important aspects of the dynamics of antimicrobial use in dairy production and the potential impacts on the main pathogens circulating in this environment, considering the parameters set by the World Health Organization (WHO) regarding the priority of monitoring as well as control strategies for these agents, such as the methicillin-resistant Staphylococcus and the beta-lactamase-producing Escherichia coli. Understanding the animal-environment-pathogen triad is crucial for establishing control measures and preventing the spread of bacterial resistance. Implementing mastitis prevention and control measures in dairy farms, considering process flow and personnel qualification, enables a reduction in antimicrobial usage and contributes to prevent the spread of resistant bacterial agents in the dairy production environment, minimizing the relapses and the chronicity of the infectious process.


A utilização de antimicrobianos no controle de mastite em ambiente de produção leiteira deve considerer alguns aspectos como a etiologia, os sinais clínicos, os impactos económicos e a legislação. O objetivo da presente revisão é destacar aspectos importantes na dinâmica do uso de antimicrobianos na produção leiteira e os potenciais impactos sobre os principais patógenos circulantes neste ambiente, considerando os parâmetros estabelecidos pela Organização Mundial da Saúde (OMS) quanto à prioridade de monitoramento, bem como estratégias de controle para esses agentes, como o Staphylococcus resistente à meticilina e a Escherichia coli produtora de beta-lactamase. Compreender a tríade animal-ambiente-patógeno é crucial para estabelecer medidas de controle e prevenir a propagação da resistência bacteriana. A implementação de medidas de prevenção e controle de mastites nas propriedades leiteiras, considerando o fluxo do processo e a qualificação do pessoal, permite a redução do uso de antimicrobianos e contribui para prevenir a propagação de agentes bacterianos resistentes no ambiente de produção leiteira, minimizando as recidivas e a cronicidade do processo infeccioso.

2.
Animals (Basel) ; 14(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39061485

RESUMO

Mastitis, an important disease in dairy cows, causes significant losses in herd profitability. Accurate diagnosis is crucial for adequate control. Studies using artificial intelligence (AI) models to classify, identify, predict, and diagnose mastitis show promise in improving mastitis control. This bibliometric review aimed to evaluate AI and bovine mastitis terms in the most relevant Scopus-indexed papers from 2011 to 2021. Sixty-two documents were analyzed, revealing key terms, prominent researchers, relevant publications, main themes, and keyword clusters. "Mastitis" and "machine learning" were the most cited terms, with an increasing trend from 2018 to 2021. Other terms, such as "sensors" and "mastitis detection", also emerged. The United States was the most cited country and presented the largest collaboration network. Publications on mastitis and AI models notably increased from 2016 to 2021, indicating growing interest. However, few studies utilized AI for bovine mastitis detection, primarily employing artificial neural network models. This suggests a clear potential for further research in this area.

4.
Crit Rev Microbiol ; : 1-14, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916977

RESUMO

Bovine mastitis is a mammary gland inflammation that can occur due to infectious pathogens, Staphylococcus aureus and Escherichia coli, which are, respectively, the most prevalent Gram-positive and Gram-negative bacteria associated with this disease. Currently, antibiotic treatment has become more complicated due to the presence of resistant pathogens. This review, therefore, aims to identify the most common resistance genes reported for these strains in the last four years. During the review, it was noted that blaZ, blaSHV, blaTEM, and blaampC are the most reported genes for S. aureus and E. coli, associated with drug inactivation, mainly ß-lactamases. They are characterized by generating bacterial resistance to ß-lactam antibiotics, the most common treatment in animal and human bacterial treatments (penicillins and cephalosporins, among others). Genes associated with efflux systems were also present in the two strains and included norA, tetA, tetC, and tetK, which generate resistance to macrolide and tetracycline antibiotics. Additionally, the effects of spreading resistance between animals and humans through direct contact (such as consumption of contaminated milk) or indirect contact (through environmental contamination) has been deeply discussed, emphasizing the importance of having adequate sanitation and antibiotic control and administration protocols.

5.
Vet Sci ; 11(6)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38921980

RESUMO

Bovine mastitis is an important and costly disease to dairy cattle. Diagnostic methods usually performed in Brazil are somatic cell counts (SCC) and milk microbiology. Low bacteria shedding in milk implies no colony growth in microbiological tests and false negative results. Streptococcus agalactiae and Staphylococcus aureus are principal pathogens of mixed mastitis. However, S. agalactiae has a higher bacterial release from the mammary gland than S. aureus, affecting microbiological sensitivity to diagnose S. aureus. This study aimed to estimate the SCC and total bacterial count (TBC) from cows according to pathogen isolated in milk and to evaluate variation in S. aureus diagnosis by a microbiological test during S. agalactiae treatment, which is called blitz therapy. Both S. agalactiae and S. aureus presented high SCC means, although S. agalactiae showed shedding of bacteria 2.3 times greater than S. aureus. Microbiological sensitivity to S. aureus increased for 5 months during S. agalactiae treatment. The prevalence of S. agalactiae fell after 5 months of therapeutic procedures. The prevalence of S. aureus increased to 39.0. The results showed that due to high sensitivity, the polymerase chain reaction (PCR) could be used at the beginning of blitz therapy with the goal of S. agalactiae eradication from the dairy herd.

6.
J Vet Sci ; 25(4): e42, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38910306

RESUMO

IMPORTANCE: Bovine mastitis, predominantly associated with gram-positive Staphylococcus aureus, poses a significant threat to dairy cows, leading to a decline in milk quality and volume with substantial economic implications. OBJECTIVE: This study investigated the incidence, virulence, and antibiotic resistance of S. aureus associated with mastitis in dairy cows. METHODS: Fifty milk-productive cows underwent a subclinical mastitis diagnosis, and the S. aureus strains were isolated. Genomic DNA extraction, sequencing, and bioinformatic analysis were performed, supplemented by including 124 S. aureus genomes from cows with subclinical mastitis to enhance the overall analysis. RESULTS: The results revealed a 42% prevalence of subclinical mastitis among the cows tested. Genomic analysis identified 26 sequence types (STs) for all isolates, with Mexican STs belonging primarily to CC1 and CC97. The analyzed genomes exhibited multidrug resistance to phenicol, fluoroquinolone, tetracycline, and cephalosporine, which are commonly used as the first line of treatment. Furthermore, a similar genomic virulence repertoire was observed across the genomes, encompassing the genes related to invasion, survival, pathogenesis, and iron uptake. In particular, the toxic shock syndrome toxin (tss-1) was found predominantly in the genomes isolated in this study, posing potential health risks, particularly in children. CONCLUSION AND RELEVANCE: These findings underscore the broad capacity for antibiotic resistance and pathogenicity by S. aureus, compromising the integrity of milk and dairy products. The study emphasizes the need to evaluate the effectiveness of antibiotics in combating S. aureus infections.


Assuntos
Genoma Bacteriano , Mastite Bovina , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Bovinos , Mastite Bovina/microbiologia , México/epidemiologia , Feminino , Staphylococcus aureus/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/epidemiologia , Virulência/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética
7.
Trop Anim Health Prod ; 56(5): 165, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753181

RESUMO

In herds of dairy goats, mastitis represents a major health and economic problem due to the multiresistance of some microorganisms. In this context, the study aimed to determine the potential of antimicrobial action and antibiofilm of the crude ethanolic extract (CEE) of Hymenaea martiana (jatobá) leaves, as well its fractions, on Staphylococcus sp isolated from bacterial cultures of goat milk. In vitro assays were performed to determine the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC), as well as tests of the effect of CEE on biofilm formation and quantification and the consolidated biofilm. The experimental infection was performed in two groups, each consisting of five goat. Experimental Group 1 (G1) consisted of five females treated with an intramammary ointment based on the CEE, at a concentration of 5%. Experimental Group 2 (G2) consisted of five females treated with a commercial intramammary ointment based on gentamicin, once a day, for six consecutive days. The diagnosis of mastitis was performed using a bacterial culture. The dichloromethane fraction of CEE was the one with the lowest concentrations of MBC, ranging from 195.3 to 781 µg / ml. Concerning to the biofilm, interference of the tested extract was observed for two isolates. In the present study, the ointment prepared from H. martiana extract (jatobá) was able to reduce bacterial infection in mammary glands experimentally infected with S. aureus. Antibacterial activity may be related to the classes of secondary metabolites found.


Assuntos
Antibacterianos , Biofilmes , Doenças das Cabras , Cabras , Mastite , Testes de Sensibilidade Microbiana , Extratos Vegetais , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Feminino , Doenças das Cabras/tratamento farmacológico , Doenças das Cabras/microbiologia , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Mastite/veterinária , Mastite/tratamento farmacológico , Mastite/microbiologia , Testes de Sensibilidade Microbiana/veterinária , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Extratos Vegetais/farmacologia , Extratos Vegetais/administração & dosagem , Biofilmes/efeitos dos fármacos , Leite/microbiologia , Folhas de Planta/química
8.
Antibiotics (Basel) ; 13(5)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38786118

RESUMO

Group B Streptococcus (GBS) is a major cause of contagious bovine mastitis (CBM) in Brazil. The GBS population is composed of host-generalist and host-specialist lineages, which may differ in antimicrobial resistance (AMR) and zoonotic potential, and the surveillance of bovine GBS is crucial to developing effective CBM control and prevention measures. Here, we investigated bovine GBS isolates (n = 156) collected in Brazil between 1987 and 2021 using phenotypic testing and whole-genome sequencing to uncover the molecular epidemiology of bovine GBS. Clonal complex (CC) 61/67 was the predominant clade in the 20th century; however, it was replaced by CC91, with which it shares a most common recent ancestor, in the 21st century, despite the higher prevalence of AMR in CC61/67 than in CC91, and high selection pressure for AMR from indiscriminate antimicrobial use in the Brazilian dairy industry. CC103 also emerged as a dominant CC in the 21st century, and a considerable proportion of herds had two or more GBS strains, suggesting poor biosecurity and within-herd evolution due to the chronic nature of CBM problems. The majority of bovine GBS belonged to serotype Ia or III, which was strongly correlated with CCs. Ninety-three isolates were resistant to tetracycline (≥8 µg/mL; tetO = 57, tetM = 34 or both = 2) and forty-four were resistant to erythromycin (2.0 to >4 µg/mL; ermA = 1, ermB = 38, mechanism unidentified n = 5). Only three isolates were non-susceptible to penicillin (≥8.0 µg/mL), providing opportunities for improved antimicrobial stewardship through the use of narrow-spectrum antimicrobials for the treatment of dairy cattle. The common bovine GBS clades detected in this study have rarely been reported in humans, suggesting limited risk of interspecies transmission of GBS in Brazil. This study provides new data to support improvements to CBM and AMR control, bovine GBS vaccine design, and the management of public health risks posed by bovine GBS in Brazil.

9.
Front Cell Infect Microbiol ; 14: 1339285, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720961

RESUMO

Antimicrobial peptides (AMPs), often referred to as nature's antibiotics, are ubiquitous in living organisms, spanning from bacteria to humans. Their potency, versatility, and unique mechanisms of action have garnered significant research attention. Unlike conventional antibiotics, peptides are biodegradable, adding to their appeal as potential candidates to address bacterial resistance in livestock farming-a challenge that has been under scrutiny for decades. This issue is complex and multifactorial, influenced by a variety of components. The World Health Organization (WHO) has proposed a comprehensive approach known as One Health, emphasizing the interconnectedness of human-animal-environment relationships in tackling such challenges. This review explores the application of AMPs in livestock farming and how they can mitigate the impact of this practice within the One Health framework.


Assuntos
Peptídeos Antimicrobianos , Gado , Saúde Única , Gado/microbiologia , Animais , Humanos , Peptídeos Antimicrobianos/farmacologia , Farmacorresistência Bacteriana , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos
10.
Bol. latinoam. Caribe plantas med. aromát ; 23(3): 401-409, mayo 2024. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1538160

RESUMO

Bovine mastitis is a disease wi th far - reaching consequences for the dairy industry. Staphylococcus aureus is a pathogen that is especially resistant to antibiotics. The objective of this study was to evaluate the antimicrobial activity of the essential oils Lippia citriodora (Lam.), Thy mus vulgaris (L), and a mixture of the essential oils Lippia citriodora and Thymus vulgaris (50/50 v/v), against isolates of oxacillin - resistant Staphylococcus aureus (n=15) of positive cases of bovine mastitis. For the statistical analysis, the IBM SPSS s tatistical package was used. The mixture of essential oils ( Lippia citriodora and Thymus vulgaris (50/50 v/v)) obtained the most significant antimicrobial activity in relation to pure essential oils. It is therefore concluded that the mixture of these oils boosts their antimicrobial activity ( p <0.05). The minimum inhibitory and bactericidal concentration of this mixture for the total isolations was 12 µL/L and 25 µL/mL, respectively.


La mastitis bovina es una enfermedad de gran impacto para la industria lechera. El Staphylococcus aureus es uno de los principales patógenos, especialmente aquellos resistentes a los antibióticos. El objetivo de este estudio fue evaluar la actividad antimicrobiana de los aceites esenciales de Lippia citriodora (Lam.), Thymus vulgaris (L), y una mezcla de aceites esenciales de Lippia citriodora y Thymus vulgaris (50/50 v/v), frente a aislamientos clínicos de Staph ylococcus aureus oxacilino - resistentes (n=15) de mastitis bovina. Se utilizó p rograma estadístico IBM SPSS y se concluyó la diferencia significativa a un p <0.05. La mezcla de aceites esenciales ( Lippia citriodora y Thymus vulgaris (50/50 v/v)), obtuvo la m ayor actividad antimicrobiana en relación a los aceites esenciales puros, se concluye que la mezcla de estos aceites potencia su actividad antimicrobiana ( p <0.019). La concentración mínima inhibitoria y bactericida de esta mezcla fue del 12 µL/mL y 25 µL/m L, respectivamente, y puede ser una alternativa terapéutica.


Assuntos
Animais , Feminino , Bovinos , Staphylococcus aureus/efeitos dos fármacos , Óleos Voláteis/farmacologia , Lippia/química , Thymus (Planta) , Mastite Bovina/microbiologia , Antibacterianos/farmacologia , Staphylococcus aureus/isolamento & purificação , Resistência Microbiana a Medicamentos , Óleos Voláteis/química , Testes de Sensibilidade Microbiana , Colômbia , Antibacterianos/química
11.
J Bacteriol ; 206(5): e0007124, 2024 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-38629875

RESUMO

Bovine mastitis is a frequent infection in lactating cattle, causing great economic losses. Staphylococcus aureus represents the main etiological agent, which causes recurrent and persistent intramammary infections because conventional antibiotics are ineffective against it. Mastoparan-like peptides are multifunctional molecules with broad antimicrobial potential, constituting an attractive alternative. Nevertheless, their toxicity to host cells has hindered their therapeutic application. Previously, our group engineered three mastoparan-L analogs, namely mastoparan-MO, mastoparan-R1, and [I5, R8] MP, to improve cell selectivity and potential. Here, we were interested in comparing the antibacterial efficacy of mastoparan-L and its analogs against bovine mastitis isolates of S. aureus strains, making a correlation with the physicochemical properties and structural arrangement changes promoted by the sequence modifications. As a result, the analog's hemolytic and/or antimicrobial activity was balanced. All the peptides displayed α-helical folding in hydrophobic and membrane-mimetic environments, as determined by circular dichroism. The peptide [I5, R8] MP stood out for its enhanced selectivity and antibacterial features related to mastoparan-L and the other derivatives. Biophysical approaches revealed that [I5, R8] MP rapidly depolarizes the bacterial membrane of S. aureus, causing cell death by subsequent membrane disruption. Our results demonstrated that the [I5, R8] MP peptide could be a starting point for the development of peptide-based drugs for the treatment of bovine mastitis, with the advantage of no residue in milk, which would help reduce the use of classical antibiotics.IMPORTANCEStaphylococcus aureus is a leading cause of mastitis, the world's most important dairy cattle disease. The multidrug resistance and zoonotic potential of S. aureus, besides the likelihood of antibiotic residues in milk, are of critical concern to public and animal health. Antimicrobial peptides offer a novel antimicrobial strategy. Here, we demonstrate that [I5, R8] MP is a potent and selective peptide, which acts on S. aureus by targeting the bacterial membrane. Therefore, understanding the physicochemical determinants and the modes of action of this class of antimicrobials opens novel prospects for peptide development with enhanced activities in the bovine mastitis context.


Assuntos
Antibacterianos , Peptídeos e Proteínas de Sinalização Intercelular , Mastite Bovina , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Bovinos , Mastite Bovina/microbiologia , Mastite Bovina/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Feminino , Antibacterianos/farmacologia , Antibacterianos/química , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/tratamento farmacológico , Peptídeos/farmacologia , Peptídeos/química , Venenos de Vespas/farmacologia , Venenos de Vespas/química
12.
J Dairy Res ; 91(1): 44-56, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38584301

RESUMO

Non-aureus staphylococci (NAS) are gaining importance in mastitis and public health, and some NAS have been reclassified as mammaliicocci (NASM). Bovine milk production has a major influence on the world economy, being an essential source of income for small, medium and large producers, and bovine mastitis caused by NASM can cause an economic impact. Mastitis generates financial losses due to reduced revenue, increased veterinary costs and expenses associated with animal slaughter. However, it is also a public health issue involving animal health and welfare, human health and the ecosystem. Furthermore, it is an increasingly common infection caused by NASM, including antimicrobial-resistant strains. Despite all these adverse effects that NASM can cause, some studies also point to its protective role against mastitis. Therefore, this review article addresses the negative and positive aspects that NASM can cause in bovine mastitis, the virulence of the disease and resistance factors that make it difficult to treat and, through the One Health approach, presents a holistic view of how mastitis caused by NASM can affect both animal and human health at one and the same time.


Assuntos
Mastite Bovina , Staphylococcus , Bovinos , Animais , Mastite Bovina/microbiologia , Feminino , Humanos , Staphylococcus/efeitos dos fármacos , Virulência , Leite/microbiologia , Farmacorresistência Bacteriana , Antibacterianos/farmacologia
13.
BMC Vet Res ; 20(1): 146, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38641805

RESUMO

BACKGROUND: The periparturient period in dairy cows is marked by immunosuppression which increases the likelihood of infectious disorders, particularly also mastitis. An in-depth understanding of peripartum leukocyte biology is vital for the implementation of highly successful post-partum disease prevention measures. Immune checkpoint molecules, such as programmed death 1 (PD-1) and cytotoxic T-lymphocyte antigen 4 (CTLA-4), are critical inhibitory receptors expressed on immune cells, particularly T cells, that drive immunosuppressive signaling pathways. However, the potential role of immune checkpoint molecules expression in T-cells on udder health has never been explored. Thus, the association between the occurrence of new postpartum intramammary infections (IMIs) and the expression of programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) on blood T-cells during the peripartum period was investigated. RESULTS: In this study, the incidence of IMIs by any pathogen in early lactation was not associated with a higher expression of PD-1 and CTLA-4 in the periparturient period. However, the incidence of IMIs by major pathogens throughout the first month of lactation was significantly associated with higher expression of PD-1 at 14 days before calving (P = 0.03) and CTLA-4 at parturition (P = 0.03) by blood T-cells. Also, the expression of CTLA-4 at D0 (P = 0.012) by T-cells was associated with the occurrence of persistent IMIs during the first month of lactation. CONCLUSIONS: To our knowledge, this is the first report to investigate the expression of PD-1 and CTLA-4 by blood T-lymphocytes during the periparturient period in dairy cows and to explore their relationship with the incidence of new IMIs in the postpartum period. Thus, a comprehensive understanding of leukocyte biology during peripartum would appear to be a prerequisite for the identification of resilient dairy cows or targets innovative (immunological) non-antibiotic approaches in the transition period.


Assuntos
Proteínas de Checkpoint Imunológico , Receptor de Morte Celular Programada 1 , Feminino , Bovinos , Animais , Antígeno CTLA-4 , Lactação/fisiologia , Linfócitos T , Leite
14.
Vet Sci ; 11(4)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38668437

RESUMO

This study aimed to assess (a) the biofilm producer ability and antimicrobial resistance profiles of Staphylococcus (Staph.) aureus and Streptococcus (Strep.) uberis isolated from cows with clinical mastitis (CM) and subclinical mastitis (SCM), and (b) the association between biofilm producer ability and antimicrobial resistance. We isolated a total of 197 Staph. aureus strains (SCM = 111, CM = 86) and 119 Strep. uberis strains (SCM = 15, CM = 104) from milk samples obtained from 316 cows distributed in 24 dairy herds. Biofilm-forming ability was assessed using the microplate method, while antimicrobial susceptibility was determined using the disk diffusion method against 13 antimicrobials. Among the isolates examined, 57.3% of Staph. aureus and 53.8% of Strep. uberis exhibited the ability to produce biofilm, which was categorized as strong, moderate, or weak. In terms of antimicrobial susceptibility, Staph. aureus isolates displayed resistance to penicillin (92.9%), ampicillin (50.8%), and tetracycline (52.7%). Conversely, Strep. uberis isolates exhibited resistance to penicillin (80.6%), oxacillin (80.6%), and tetracycline (37.8%). However, no significant correlation was found between antimicrobial resistance patterns and biofilm formation ability among the isolates.

15.
Materials (Basel) ; 17(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38612142

RESUMO

The growing resistance of bacteria to antibiotics is one of the main public health problems nowadays. The influence of silver nanoparticle (AgNP) pretreatment of 220 cows with mastitis on the susceptibility of Staphylococcus epidermidis bacteria to 31 antibiotics was studied. The obtained results were compared with the previous results for Escherichia coli, Streptococcus dysgalactiae, and Staphylococcus aureus. For all four bacteria, an increase in susceptibility (9.5-21.2%) to 31 antibiotics after cow treatment with AgNPs was revealed, while after first-line antibiotic drug treatment as expected, the susceptibility decreased (11.3-27.3%). These effects were explained by (1) the increase in the contribution of isolates with efflux effect after antibiotic treatments and its decrease after AgNP treatment and (2) the changes in bacteria adhesion and anti-lysozyme activity after these treatments. The effect of the increasing antibacterial activity of antibiotics after AgNP treatment was the most pronounced in the case of E. coli and was minimal in the case of S. epidermidis. With AgNP treatment, the time of recovery decreased by 26.8-48.4% compared to the time of recovery after treatment with the first-line antibiotic drugs. The AgNP treatment allows for achieving the partial restoration of the activity of antibiotics.

16.
An. Fac. Cienc. Méd. (Asunción) ; 57(1): 77-81, 20240401.
Artigo em Espanhol | LILACS | ID: biblio-1554450

RESUMO

La mastitis linfocítica o mastitis diabética es una patología benigna rara, caracterizada por una inflamación fibrótica de la mama, causando gran preocupación por la simulación de un carcinoma. Está asociada por lo general a la diabetes tipo 2, aunque pueden presentarse en otras patologías autoinmunes y además en pacientes sin comorbilidades. Se presenta en caso clínico de una paciente joven sin comorbilidades que consulto en consultorio de patología mamaria por tumor mamario. Se realizó una biopsia percutánea por trucut con confirmación histológica de mastitis linfocítica, se realizó control cercano observándose remisión clínica e imagenológica de la lesión en 6 meses de seguimiento. Se presenta el caso a fin de recalcar la importancia del diagnóstico histológico percutáneo de la lesión para determinar la naturaliza de la misma, constatándose una patología benigna que no requiere resección, evitando así causar deformidades que podrían afectar psicológicamente a la paciente.


Lymphocytic mastitis or diabetic mastitis is a rare benign pathology, characterized by fibrotic inflammation of the breast, causing great concern due to the simulation of carcinoma. It is generally associated with type 2 diabetes, although it can occur in other autoimmune pathologies and also in patients without comorbidities. The clinical case of a young patient without comorbidities who consulted in the breast pathology clinic due to a breast tumor. A percutaneous trucut biopsy was performed with histological confirmation of lymphocytic mastitis, close control was performed, observing clinical and imaging remission of the lesion in 6 months of follow-up. The case is presented in order to emphasize the importance of percutaneous histological diagnosis of the lesion, to determine its nature, confirming a benign pathology that does not require resection, thus avoiding causing deformities that could psychologically affect the patient.


Assuntos
Doença da Mama Fibrocística , Biópsia , Mastite
17.
J Steroid Biochem Mol Biol ; 240: 106508, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38521361

RESUMO

Mastitis is one the most widespread and serious diseases in dairy cattle. Recurrent and chronic infections are often attributable to certain pathogenicity mechanisms in mastitis-causing pathogens such as Staphylococcus spp. These include growing in biofilm and invading cells, both of which make it possible to resist or evade antimicrobial therapies and the host's immune system. This study tested the effects of active vitamin D3 (i.e., calcitriol or 1,25-dihydroxyvitamin D3) on the internalization and phagocytosis of biofilm-forming Staphylococcus spp. isolated from animals with mastitis. Two established bovine cell lines were used: MAC-T (mammary epithelial cells) and BoMac (macrophages). Calcitriol (0-200 nM) did not affect the viability of MAC-T cells nor that of BoMac cells after 24 and 72 h. Concentrations of 0-100 mM for 24 h upregulated the expression of 24-hydroxylase in MAC-T cells, but did not alter that of VDR. Pre-treatment of the cells with calcitriol for 24 h decreased the internalization of S. aureus V329 into MAC-T cells (0-100 nM), and stimulated the phagocytosis of the same strain and of S. xylosus 4913 (0-10 nM). Calcitriol and two conditioned media, obtained by treating the cells with 25-200 nM of the metabolite for 24 h, were also assessed in terms of their antimicrobial and antibiofilm activity. Neither calcitriol by itself nor the conditioned media affected staphylococcal growth or biofilm formation (0-200 nM for 12 and 24 h, respectively). In contrast, the conditioned media (0-100 nM for 24 h) decreased the biomass of preformed non-aureus staphylococcal biofilms and killed the bacteria within them, without affecting metabolic activity. These effects may be mediated by reactive oxygen species and proteins with antimicrobial and/or antibiofilm activity. In short, calcitriol could make pathogens more accessible to antimicrobial therapies and enhance bacterial clearance by professional phagocytes. Moreover, it may modulate the host's endogenous defenses in the bovine udder and help combat preformed non-aureus staphylococcal biofilms (S. chromogenes 40, S. xylosus 4913, and/or S. haemolyticus 6). The findings confirm calcitriol's potential as an adjuvant to prevent and/or treat intramammary infections caused by Staphylococcus spp., which would in turn contribute to reducing antibiotic use on dairy farms.


Assuntos
Biofilmes , Imunidade Inata , Mastite Bovina , Fagocitose , Staphylococcus , Animais , Bovinos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Feminino , Mastite Bovina/microbiologia , Mastite Bovina/imunologia , Imunidade Inata/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Calcitriol/farmacologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/tratamento farmacológico , Linhagem Celular , Glândulas Mamárias Animais/microbiologia , Glândulas Mamárias Animais/imunologia , Macrófagos/microbiologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo
18.
Braz J Microbiol ; 55(1): 955-967, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38265572

RESUMO

Mastitis caused by Staphylococcus aureus is a worldwide problem in dairy farms, in part because of the pathogenicity of the bacteria, biofilm formation, and mechanisms of antimicrobial resistance that make the disease difficult to diagnose and treat, which is typically done with the use of beta-lactam antibiotics. The aim of the present study was to determine the virulence and resistance factors of S. aureus isolates from subclinical mastitis, blaZ + /mecA - /mecC - , resistant and sensitive to oxacillin. All isolates were classified as CC97 by MLST analysis, a clonal complex well adapted to the mammary gland and although STAU23 and STAU73 were resistant to oxacillin while STAU32 and STAU78 were sensitive, the genomic analysis identified only the blaZ operon corresponding to resistance to beta-lactams. However, the presence of the sdrC gene was revealed exclusively in resistant isolates, an important adhesin in the colonization process that potentiates pathogenicity in S. aureus. In addition, resistance islands (REIs) were identified in these isolates, suggesting more conserved REIs. In the analysis of SNPs throughout the genome, mutations were found in the trmB and smpB genes of the resistant isolates and in the murD and rimM genes of the sensitive isolates. This study highlights the potential benefit of genome-wide characterization tools to identify molecular mechanisms of S. aureus in bovine mastitis.


Assuntos
Mastite Bovina , Infecções Estafilocócicas , Animais , Bovinos , Feminino , Humanos , Staphylococcus aureus , Antibacterianos/farmacologia , Virulência/genética , Tipagem de Sequências Multilocus , Testes de Sensibilidade Microbiana , Mastite Bovina/microbiologia , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Oxacilina
19.
Bol. latinoam. Caribe plantas med. aromát ; 23(1): 29-40, ene. 2024. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1552792

RESUMO

The essential oils of Lippia citriodora (Ort.) and Lippia origanoides (Kunth) have shown antimicrobial activity associated with mastitis. The objective of this study was to evaluate its ecotoxic effect with the Artemia salina bioassay and the prevention of mastitis through an in vivo test in cattle (n=20) with a product based on these oils using a conventional product as a control. Contact hypersensitivity, the effect on somatic cells, and residuality in mil k samples were evaluated. The results of the Artemia salina bioassay were 10.05 and 19.36 (µg/mL) respectively. No negative effects or contact hypersensitivity were observed, and no residual metabolites were found in post - test milk. The somatic cell count showed 75% effectiveness in the prevention of mastitis with essential oils compared to 62.5% with the conventional product. The evaluated formulation could be used in the prevention of bovine mastitis safely, further investigation is required.


Los aceites esenciales de Lippia citriodora (Ort.) y Lippia origanoides (Kunth), han mostrado acti vidad antimicrobiana asociada a la mastitis. El objetivo de este estudio fue evaluar su efecto ecotóxico con el bioensayo Artemia salina y la prevención de mastitis mediante un ensayo in vivo en bovinos (n=20) con un producto a base de estos aceites utiliz ando como control un producto convencional. Se evaluó la hipersensibilidad de contacto, efecto en células somáticas y residualidad en muestra de leche. Los resultados del bioensayo de Artemia salina fueron 10,05 y 19,36 (µg/mL) respectivamente. No se obser varon efectos negativos, ni hipersensibilidad de contacto, y no se encontraron metabolitos residuales en leche posterior al ensayo. El conteo de células somáticas mostró efectividad en la prevención de mastitis del 75% con aceites esenciales frente al 62.5 % del producto convencional. La formulación evaluada podría ser utilizada en la prevención de la mastitis bovina de forma segura, se requiere profundizar en la investigación.


Assuntos
Óleos Voláteis/administração & dosagem , Lippia/química , Mastite Bovina/prevenção & controle , Artemia , Terpenos/análise , Bioensaio , Óleos Voláteis/química , Hipersensibilidade , Cromatografia Gasosa-Espectrometria de Massas
20.
Vet Res Commun ; 48(1): 61-67, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37493941

RESUMO

Bovine mastitis is an emerging disease that causes large economic losses. Staphylococcus aureus its main etiological agent, is multi-resistant to antimicrobials and produces biofilm. The objective of this study was to investigate the effect of Agave fructans (AF), a type of prebiotic, on multi-resistant and biofilm-forming isolates of S. aureus. Ten isolates of S. aureus from bovine subclinical mastitis previously characterized as highly resistant to antimicrobials and biofilm formers were used in this study. The growth kinetics of S. aureus in the presence of AF was evaluated by the Baranyi and Roberts microbial growth model using the DMFit program. The antibacterial activity of AF against S. aureus was studied by the well-diffusion method and the effect on biofilm formation by the crystal violet method. All assays were performed in triplicate for each isolate and an ANOVA with Tukey's post hoc was performed considering p < 0.05 as significant. The AF showed a decrease in maximum growth rate (µmax) and OD max levels (Ymax) in all isolates with all concentrations. Also, zones of inhibition were observed due to the effect of all AF concentrations in all isolates in a dose-dependent manner. Interestingly, S. aureus biofilm formation was inhibited by all AF concentrations assessed in this study. More investigations are required to elucidate the mechanisms of action of AF on S. aureus as well as in vivo studies to evaluate its therapeutic efficacy for bovine mastitis.


Assuntos
Agave , Doenças dos Bovinos , Mastite Bovina , Infecções Estafilocócicas , Animais , Bovinos , Feminino , Staphylococcus aureus , Mastite Bovina/tratamento farmacológico , Mastite Bovina/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Antibacterianos/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana/veterinária
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