Uso de antimicrobiano nanoparticulado para o tratamento da mastite subcl?nica de ovelhas de corte no per?odo seco.

A inflama??o da gl?ndula mam?ria ? uma das principais causas de preju?zo na ovinocultura. Este estudo teve como objetivo investigar as taxas de cura do tratamento da mastite subcl?nica ap?s infus?o intramam?ria de princ?pio ativo antimicrobiano no momento da secagem, em formula??es convencional e nanoparticulada. Os rebanhos estavam localizados em S?o Carlos, S?o Paulo, Brasil. Analisou-se um total de 584 gl?ndulas mam?rias de 307 ovelhas de aptid?o para produ??o de carne. Triagem pr?via dos casos subcl?nicos de mastite foi efetuada por meio do California Mastitis Test (CMT) e/ou da contagem de c?lulas som?ticas (CCS). An?lises microbiol?gicas foram realizadas para confirma??o da etiologia infecciosa. As gl?ndulas mam?rias com mastite subcl?nica foram distribu?das em tr?s grupos: G1 (Controle; gl?ndulas mam?rias que n?o receberam tratamento antimicrobiano); G2 (gl?ndulas mam?rias em que foi administrado 100 mg de cloxacilina benzatina em estrutura convencional) e G3 (gl?ndulas mam?rias em que foi administrado 50 mg de cloxacilina benzatina em estrutura nanoencapsulada). O tratamento aplicado ao G3 mostrou-se mais eficiente (P=0,047) na cura de gl?ndulas mam?rias com mastite subcl?nica. O uso da cloxacilina nanoencapsulada no momento da secagem de ovelhas de corte auxilia no controle da mastite subcl?nica infecciosa e reduz os preju?zos consequentes.Inflammation of the mammary gland is one of the main causes of losses in sheep-rearing. This study aimed to investigate the cure rates from treating subclinical mastitis after intramammary infusion of active antimicrobial agents as conventional formulations or as nanoparticles, at the time when the ewes are being dried off. A total of 584 mammary glands in 307 ewes in meat-producing herds located in S?o Carlos, S?o Paulo, Brazil, were analyzed. Prescreening of subclinical mastitis cases was done using the California mastitis test (CMT) and/or the somatic cell count (SCC). Microbiological analyses were performed to confirm the infectious etiology. The mammary glands with subclinical mastitis were distributed into three groups: G1 (control; mammary glands that did not receive any antimicrobial treatment); G2 (mammary glands to which 100mg of benzathine cloxacillin in conventional form were administered); and G3 (mammary glands to which 50mg of benzathine cloxacillin in nanoparticulate form were administered). The treatment applied to G3 was more efficient (P=0.047) in curing mammary glands with subclinical mastitis. Use of cloxacillin nanoparticles at the time when the ewes are being dried off helps to control infectious subclinical mastitis and reduces consequential losses among meat-producing herds

Investigation of biofilm production and icaA and icaD genes in Staphylococcus aureus isolated from heifers and cows with mastitis

Biofilm formation and antimicrobial resistance of Staphylococcus aureus are important virulence factors in cases of mastitis in dairy cows. However, few studies have investigated mastitis strains isolated from heifers. Within this context, the objective of the present study was to investigate biofilm formation on Congo red agar, the presence of the icaA and icaD genes by polymerase chain reaction (PCR), and the percentage of in vitro antimicrobial resistance of 110 S.aureus isolates from mammary gland secretions of heifers and cows with mastitis. PCR detected the icaA and icaD genes in 98% and 100% of isolates, respectively. However, only 55.5% of all isolates produced a biofilm on Congo red agar. Antimicrobial susceptibility testing revealed that 47.0% of isolates from heifers and 70.4% of isolates from cows were resistant to at least one of the antimicrobial agents tested. Resistance to penicillin and/or ampicillin was the most frequent (44.5%). These results indicate the need to implement prophylactic and control measures of mastitis for heifers. Heifers and cows can carry resistant strains with the capacity of biofilm production, a fact representing a threat to public health and animal well-being and generating losses to dairy farmers.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

PERSISTENCE OF COAGULASE-NEGATIVE STAPHYLOCOCCI IN MAMMARY GLANDS OF SHEEP WITH SUBCLINICAL MASTITIS AFTER ANTIMICROBIAL TREATMENT AT DRYING-OFF

<p></p><p>Abstract Coagulase-negative Staphylococci (CNS) are the main microorganisms responsible for mastitis in sheep and the treatment in the end of lactation can be used as a control method against disease. However, the long dry period presented by ewes in some breeding systems may impair the positive effects of antimicrobial treatment. The aims of this study were to identify the main CNS species in the etiology of ovine mastitis before and after treatment at dry-off of the ewes, as well as investigate the persistence of the most prevalent species in the mammary gland at the next lactation. Sixty sheep were divided into two experimental groups, one consisting of animals without antimicrobial treatment, while the other was composed by sheep whose mammary halves were treated with cloxacillin-benzathine intramammary. The milk samples were obtained before drying-off and at 15 and 30 days after calving the next lactation. The prevalent species were S. warneri, S. simulans and S. epidermidis. Clones of the three species more prevalent were identified before and after treatment, i.e., even with the extensive dry period between the two consecutive lactations, the microorganisms were still identified in the mammary gland.</p><p></p

Rela??o entre genes de fatores de virul?ncia em Staphylococcus spp. coagulase-negativos e a falha do tratamento antimicrobiano da mastite subcl?nica ovina.

Coagulase-negative Staphylococcus spp. (CNS) are the main microorganisms involved in ovine mastitis. Treatment at the end of lactation can contribute towards cure and prevention of subclinical cases during the subsequent lactation. However, virulence factors and resistance mechanisms presented by CNS can decrease cure rates. The aims of the study were to identify the species of CNS in milk of mastitic ewes with and without antimicrobial treatment, and to investigate the presence of genes relating to resistance of ?-lactam antimicrobials, formation of biofilms, production of enterotoxins and production of the toxic shock syndrome toxin. Cases of failure in the treatment were related with the presence/absence of the respective genes. Sixty sheep were divided into three groups: G1, without treatment; G2, animals treated via the intramammary route with 100mg of cloxacillin during drying off; and G3, sheep treated via the intramammary route with 50 mg of nanoparticulate cloxacillin. Milk samples were gathered during drying off and 15 and 30 days after the parturition of the subsequent lactation. The analyses to identify the species of CNS were carried out by means of the internal transcribe spacer technique and the investigation of the genes responsible for the virulence factors and resistance to oxacillin was performed using the polymerase chain reaction (PCR) technique. No sample was positive for the mecA gene. The only gene relating to production of enterotoxins was sec. Among the genes relating to production of biofilm, icaD was the only one identified in the three experimental groups. Staphylococcus warneri was the main species of CNS isolated during the pre and post-partum periods of the sheep. The species carrying genes relating to production of enterotoxins and biofilms were present in uncured sheep.Staphylococus spp. coagulase-negativos (SCN) est?o entre os principais micro-organismos envolvidos na mastite ovina. O tratamento ao final da lacta??o pode contribuir com a cura e a preven??o de casos subcl?nicos durante a lacta??o seguinte. Todavia, fatores de virul?ncia e mecanismos de resist?ncia apresentados por SCN podem reduzir as taxas de cura. Os objetivos desse estudo foram identificar as esp?cies de SCN no leite de ovelhas com mastite com e sem tratamento antimicrobiano e investigar a presen?a de genes relacionados com resist?ncia a antibi?ticos beta lact?micos, forma??o de biofilmes, produ??o de enterotoxinas e produ??o da toxina da s?ndrome do choque t?xico. Casos de falhas no tratamento foram relacionados com a presen?a/aus?ncia dos respectivos genes. Sessenta ovelhas foram divididas em tr?s grupos: G1, sem tratamento; G2, animais tratados via intramam?ria com 100mg de cloxacilina antes da secagem; e G3, ovelhas tratadas via intramam?ria com 50 mg de cloxacilina nanoparticulada. Amostras de leite foram obtidas durante a secagem e 15 e 30 dias depois do parto na lacta??o seguinte. As an?lises para identificar as esp?cies de SCN foram conduzidas por meio da t?cnica de Internal transcribe spacer e a investiga??o dos genes respons?veis pelos fatores de virul?ncia e resist?ncia ? oxacilina foi realizada usando a t?cnica rea??o em cadeia da polimerase. Nenhuma amostra foi positiva para o gene mecA. O ?nico gene relacionado com a produ??o de enterotoxinas foi o sec. Dentre os genes relacionados com a produ??o de biofilme, icaD foi o ?nico identificado nos tr?s grupos experimentais. Staphylococcus warneri foi a principal esp?cie de SCN isolada durante o pr? e p?s-parto. As esp?cies que apresentaram genes relacionados com a produ??o de enterotoxinas e biofilmes estavam presentes nas ovelhas n?o curadas

A Survey of Empirical Results on Program Slicing

International audienceBACKGROUND:Patients with peripheral artery disease have an increased risk of cardiovascular morbidity and mortality. Antiplatelet agents are widely used to reduce these complications.METHODS:This was a multicentre, double-blind, randomised placebo-controlled trial for which patients were recruited at 602 hospitals, clinics, or community practices from 33 countries across six continents. Eligible patients had a history of peripheral artery disease of the lower extremities (previous peripheral bypass surgery or angioplasty, limb or foot amputation, intermittent claudication with objective evidence of peripheral artery disease), of the carotid arteries (previous carotid artery revascularisation or asymptomatic carotid artery stenosis of at least 50%), or coronary artery disease with an ankle-brachial index of less than 0·90. After a 30-day run-in period, patients were randomly assigned (1:1:1) to receive oral rivaroxaban (2·5 mg twice a day) plus aspirin (100 mg once a day), rivaroxaban twice a day (5 mg with aspirin placebo once a day), or to aspirin once a day (100 mg and rivaroxaban placebo twice a day). Randomisation was computer generated. Each treatment group was double dummy, and the patient, investigators, and central study staff were masked to treatment allocation. The primary outcome was cardiovascular death, myocardial infarction or stroke; the primary peripheral artery disease outcome was major adverse limb events including major amputation. This trial is registered with ClinicalTrials.gov, number NCT01776424, and is closed to new participants.FINDINGS:Between March 12, 2013, and May 10, 2016, we enrolled 7470 patients with peripheral artery disease from 558 centres. The combination of rivaroxaban plus aspirin compared with aspirin alone reduced the composite endpoint of cardiovascular death, myocardial infarction, or stroke (126 [5%] of 2492 vs 174 [7%] of 2504; hazard ratio [HR] 0·72, 95% CI 0·57-0·90, p=0·0047), and major adverse limb events including major amputation (32 [1%] vs 60 [2%]; HR 0·54 95% CI 0·35-0·82, p=0·0037). Rivaroxaban 5 mg twice a day compared with aspirin alone did not significantly reduce the composite endpoint (149 [6%] of 2474 vs 174 [7%] of 2504; HR 0·86, 95% CI 0·69-1·08, p=0·19), but reduced major adverse limb events including major amputation (40 [2%] vs 60 [2%]; HR 0·67, 95% CI 0·45-1·00, p=0·05). The median duration of treatment was 21 months. The use of the rivaroxaban plus aspirin combination increased major bleeding compared with the aspirin alone group (77 [3%] of 2492 vs 48 [2%] of 2504; HR 1·61, 95% CI 1·12-2·31, p=0·0089), which was mainly gastrointestinal. Similarly, major bleeding occurred in 79 (3%) of 2474 patients with rivaroxaban 5 mg, and in 48 (2%) of 2504 in the aspirin alone group (HR 1·68, 95% CI 1·17-2·40; p=0·0043).INTERPRETATION:Low-dose rivaroxaban taken twice a day plus aspirin once a day reduced major adverse cardiovascular and limb events when compared with aspirin alone. Although major bleeding was increased, fatal or critical organ bleeding was not. This combination therapy represents an important advance in the management of patients with peripheral artery disease. Rivaroxaban alone did not significantly reduce major adverse cardiovascular events compared with asprin alone, but reduced major adverse limb events and increased major bleeding