Efficacy of disinfection procedures performed prior to regenerative endodontic therapy: An integrative review.

The aim of this integrative review was to identify whether the disinfection procedures performed prior to regenerative endodontic treatment were effective on biofilm removal from the root canals. The research was based on PubMed, Latin American and Caribbean Health Sciences Literature (Lilacs) and Scientific Electronic Library Online (SciELO) databases. Four articles were selected; one of the studies was in vivo and the others ex vivo. Different disinfection procedures were studied, characterised mainly by the use of intracanal medication, highlighting the double antibiotic paste, triple antibiotic paste and calcium hydroxide paste. Disinfection ability was evaluated against Enterococcus faecalis and multispecies biofilms by using the fluorescence technique and colony forming unit counting, for 7 to 21 days. Double antibiotic paste and triple antibiotic paste demonstrated excellent antibiofilm activity, unlike CH paste that showed limited disinfection, even when associated with different antimicrobial agents. Triple antibiotic paste was the most effective medication against biofilm.

Diets with Ganoderma lucidum Mushroom Powder and Zinc-Bacitracin on Growth Performance, Carcass Traits, Lymphoid Organ Weights and Intestinal Characteristics in Broilers

In order to evaluate the effect of diets with Ganoderma lucidum mushroom powder and zinc-bacitracin on growth performance, carcass traits, lymphoid organ weights, and intestinal characteristics in broilers, a total of 600 one-day-old unsexed broilers from Cobb 500 MV × Cobb 500 FF genotype was analyzed for 28 days, following a completely randomized design with three dietary treatments, five replicates and 40 birds per replicate. The dietary treatments consisted of a basal diet (BD) without additives (T0) and the dietary inclusion of 2.5 g/kg of Ganoderma lucidum (T1) and 350 mg/kg of zinc bacitracin antibiotic (T2). The experimental groups did not change (p>0.05) the performance of the broilers. However, G. lucidum powder increased (p≤0.05) the carcass and breast yields (p≤0.05) and decreased the abdominal fat and liver yields (p≤0.05), although with no notable differences with the antibiotic group for the latter organ (liver) (p>0.05). Both additives (G. lucidum and antibiotic) increased breast meat moisture, protein, and redness; however, these treatments reduced L* (lightness), and the zinc-bacitracin reduced breast yellowness (p≤0.05). Likewise, this medicinal mushroom (G. lucidum) increased the relative weight of bursa of Fabricius and the morphometry of the small intestine (p≤0.05), although with no changes for other immune and digestive organs or for the content of cecal lactic acid bacteria (p>0.05). The dietary inclusion with 2.5 g/kg of Ganoderma lucidum powder is recommended to improve breast yield, protein, and colorimetry without affecting performance and cecal traits of fast-growing broilers.

Diets with Ganoderma lucidum Mushroom Powder and Zinc-Bacitracin on Growth Performance, Carcass Traits, Lymphoid Organ Weights and Intestinal Characteristics in Broilers

In order to evaluate the effect of diets with Ganoderma lucidum mushroom powder and zinc-bacitracin on growth performance, carcass traits, lymphoid organ weights, and intestinal characteristics in broilers, a total of 600 one-day-old unsexed broilers from Cobb 500 MV × Cobb 500 FF genotype was analyzed for 28 days, following a completely randomized design with three dietary treatments, five replicates and 40 birds per replicate. The dietary treatments consisted of a basal diet (BD) without additives (T0) and the dietary inclusion of 2.5 g/kg of Ganoderma lucidum (T1) and 350 mg/kg of zinc bacitracin antibiotic (T2). The experimental groups did not change (p>0.05) the performance of the broilers. However, G. lucidum powder increased (p≤0.05) the carcass and breast yields (p≤0.05) and decreased the abdominal fat and liver yields (p≤0.05), although with no notable differences with the antibiotic group for the latter organ (liver) (p>0.05). Both additives (G. lucidum and antibiotic) increased breast meat moisture, protein, and redness; however, these treatments reduced L* (lightness), and the zinc-bacitracin reduced breast yellowness (p≤0.05). Likewise, this medicinal mushroom (G. lucidum) increased the relative weight of bursa of Fabricius and the morphometry of the small intestine (p≤0.05), although with no changes for other immune and digestive organs or for the content of cecal lactic acid bacteria (p>0.05). The dietary inclusion with 2.5 g/kg of Ganoderma lucidum powder is recommended to improve breast yield, protein, and colorimetry without affecting performance and cecal traits of fast-growing broilers.(AU)

Effect of the use of probiotic Bacillus subtilis (QST 713) as a growth promoter in broilers: an alternative to bacitracin methylene disalicylate.

The global poultry trend toward the more responsible use of antibiotics is becoming recurrent and has demanded the need to generate new natural alternatives. Probiotics have gained importance as an option to use as growth promoters. This study aimed to evaluate Bacillus subtillis QST713 as a substitute for an antibiotic growth promoter (BMD). A total of 150 male broilers were assigned to three dietary treatments: 1) control diet (CO), 2) control diet + 500 g/t of BMD (AGP), and 3) control diet + 100 g/t of B. subtilis QST713 (PB), respectively. Each treatment was monitored for 5 wk for the productive variables: body weight, accumulated feed consumption, food conversion, and European efficiency factor. At the end of each week, fresh fecal samples were cultured and quantified for E. coli, Enterococcus spp., and Lactobacillus spp. At the end of the trial, blood samples were analyzed for hemogram and intestinal samples (anterior portion) for histomorphometry. The data were statistically analyzed with an analysis of variance and subjected to a least significant difference test (Tukey). The zootechnical yields were similar in the AGP and PB groups (P ˃ 0.05); both superior to the control group. In the hematological profiles, no difference was observed between the experimental groups. E. coli and Enterococcus counts were significantly lower (P ˂ 0.05), and Lactobacillus counts were significantly (P ˂ 0.05) higher in the PB group, relative to CO and AGP groups. No differences (P ˃ 0.05) were found in bacterial counts between the CO and AGP groups. The intestinal mucosa and villi in the PB group were significantly (P ˂ 0.05) longer and with less deeper crypts than CO and AGP groups. We conclude that B. subtillis QST713, used at the suggested commercial dose (100 g/ton), is an effective growth-promoting alternative to BMD that modulates the microbiota and intestinal architecture, thus producing zootechnical yields consistent with BMD.

A comprehensive dynamic kinetic model for the UVC/H2O2 process: application to zinc bacitracin degradation in wastewater as a case study.

A dynamic kinetic model is presented for the UVC/H2O2-driven process. The model comprises 103 reactions, including background species, such as HCO3-/CO32-, NO2-, NO3-, SO42-, Cl-, and H2PO4-/HPO42/PO43- anions, and effluent organic matter (EfOM) was validated based on experimental data obtained for the photooxidation of the nonribosomal peptide antibiotic zinc bacitracin (Zn-Bc, 34 µmol L-1). The set of ordinary differential equations for 38 species was combined with the molar balances describing the recirculating tubular photoreactor used. Predictions for the photolytic and UVC/H2O2 processes confirmed the good agreement with experimental data, enabling the estimation of fundamental kinetic parameters, such as the direct photolysis quantum yield (Ф254 nm, Zn-Bc = 0.0143 mol Einstein-1) and the second-order rate constants for the reactions of Zn-Bc with HO•, HO2•, and O2•- radicals (2.64 × 109, 1.63 × 103, and 1.49 × 104 L mol-1 s-1, respectively). The predicted optimum process conditions correspond to [H2O2]0 = 6.8 mmol L-1 and a specific photon emission rate of 11.1 × 10-6 Einstein L-1 s-1. Zn-Bc photooxidation was significantly impacted by wastewater constituents, particularly EfOM and HCO3-/CO32- (i.e., alkalinity), resulting in a degradation rate about 32% lower compared to that obtained in deionized water. In particular, EfOM acts as a strong radical scavenger and inner filter. In addition, simulations pointed out the continuous tubular photochemical reactor as the best configuration for treating Zn-Bc-containing wastewater. This study hence provides a comprehensive modeling approach, especially useful for predicting the effect of complex water matrices on the performance of the UVC/H2O2 treatment process.

Bacitracin is a non-competitive inhibitor of porcine M1 family neutral and glutamyl aminopeptidases.

Membrane alanyl and glutamyl aminopeptidases (APN and APA, respectively) are established targets for the development of biomedical tools in human pathologies. APN overexpression correlates with the progression of tumours, including melanoma. Bacitracin, widely used as a topical antibiotic, inhibits subtilisin-like serine peptidases and disulphide isomerases. In the present contribution, we demonstrate that bacitracin is a non-competitive α = 1 and α < 1 inhibitor of porcine kidney APN and APA, respectively, with Ki values in the micromolar range. To test a potential application of this result, we assayed the effect of bacitracin on murine melanoma MB16F10 cell line viability. We demonstrated the cell line expresses an APN-like activity inhibited by bacitracin and bestatin. Additionally, we identified a cytotoxic effect of bacitracin. Further experiments are required to understand in depth the mechanisms of action of bacitracin on melanoma cells. They will clarify the therapeutic potential of bacitracin for melanoma treatment.

UVC- and UVC/H2O2-Driven nonribosomal peptide antibiotics degradation: application to zinc bacitracin as a complex emerging contaminant.

Zinc bacitracin (Zn-Bc) belongs to the group of nonribosomal peptide antibiotics (NRPA), comprising a mixture of non-biodegradable congeners characterized by complex structures containing cyclic, polycyclic, and branched chains. However, reports on the use of AOPs for the degradation of NRPA are non-existent. In this context, the present work investigated the photodegradation of Zn-Bc in aqueous solution by direct photolysis and the UVC/H2O2 process. The effects of the specific UVC photon emission rate and initial H2O2 concentration were studied following a Doehlert-design response surface approach. The results showed that all congeners photolyzed at the highest UVC doses in the absence of hydrogen peroxide, with a calculated quantum yield of 0.0141 mol Zn-Bc mol photons-1. However, no TOC removal was observed after 120 minutes of irradiation, suggesting the disruption of the peptide bonds in the antibiotic molecules without significant changes in the amino acid residues. The addition of H2O2 substantially accelerated Zn-Bc photodegradation, resulting in a remarkable removal of up to 71% of TOC. Most importantly, the antimicrobial activity against Staphylococcus aureus could be completely removed by both treatments. These findings point out that the UVC/H2O2 process can be straightly engineered for the treatment of metalloantibiotics-containing wastewater in pharmaceutical facilities.

Probiotic and synbiotic in broiler diet: performance and Enterobacteriaceae / [Probiótico e simbiótico em ração para frangos: desempenho e Enterobacteriaceae]

The objective of this study was to evaluate the effects of probiotics and synbiotics on the performance and Enterobacteriaceae count of broiler chickens. A total of 640 one-day-old male broiler chicks were distributed in a completely randomized design with four treatments and eight replicates with 20 birds each. The treatments were: ration with performance enhancer (zinc bacitracin; positive control); ration without performance enhancer and probiotic/synbiotic (negative control); ration with probiotics; and ration with synbiotics. At 35 days, five birds from each treatment were euthanized and intestinal contents were harvested for determining the Enterobacteriaceae count. The performance data and average colony-forming units (CFUs) transformed as log CFU/g were subjected to analysis of variance and Tukey's test. The effects of probiotics and synbiotics were observed in the initial phase, with supplemented birds exhibiting comparable weight gain to those supplemented with bacitracin. No effect of the treatment on broiler performance was observed after 42 days. The enterobacterial count was comparable among all experimental treatments. Supplementation with probiotics and synbiotics did not compromise the performance of broilers and did not alter the Enterobacteriaceae count.(AU)

Objetivou-se avaliar o efeito do probiótico e do simbiótico sobre o desempenho e a contagem de Enterobacteriaceae em frangos. Foram utilizados 640 pintos de corte, machos, de um dia de idade, distribuídos em delineamento inteiramente ao acaso, com quatro tratamentos, oito repetições com 20 aves cada. Os tratamentos foram: ração com melhorador de desempenho (bacitracina de zinco) (controle positivo); ração sem melhorador de desempenho e sem probiótico/simbiótico (controle negativo); ração com probiótico e ração com simbiótico. Aos 35 dias, cinco aves por tratamento foram eutanasiadas para retirada de conteúdo intestinal e determinação de Enterobacteriaceae. As médias das unidades formadoras de colônias, transformadas em log/UFC/g, e de desempenho foram submetidas à análise de variância e comparadas pelo teste Tukey. Foi observado efeito do probiótico e do simbiótico na fase inicial, sendo que aves apresentaram os mesmos resultados de ganho de peso e de peso corporal que o grupo de aves alimentado com bacitracina. Aos 42 dias, não houve efeito dos tratamentos sobre o desempenho. Aves que não receberam nenhum aditivo não apresentaram maior contagem de enterobactérias, sendo semelhantes aos demais tratamentos. A adição do probiótico e do simbiótico não compromete o desempenho dos frangos e não altera a contagem de Enterobacteriaceae.(AU)

Bestatin and bacitracin inhibit porcine kidney cortex dipeptidyl peptidase IV activity and reduce human melanoma MeWo cell viability.

Bestatin and bacitracin are inhibitors of metallo aminopeptidases and bacterial proteases. However, their effects on other human peptidases, like dipeptidyl peptidase IV (DPP-IV, EC 3.4.14.5) are not established. Inhibitors of DPP-IV activity are used for treating type 2 diabetes mellitus, cancers and immune system diseases. Bacitracin and bestatin inhibited porcine membrane-bound DPP-IV (pDPP-IV) activity. Mechanisms were different, i.e. non-competitive with α > 1 (α = 3.9) and Ki value of 75 µM for bestatin, and competitive with Ki value of 630 µM for bacitracin. The binding mode in the tertiary complex enzyme:substrate:bestatin suggested the structural basis of the inhibitory effect and that bestatin is potentially selective for DPP-IV, ineffective vs. S9 family members dipeptidyl peptidase 8/9 and fibroblast activation protein. In the human melanoma MeWo cell line, bestatin and bacitracin inhibited aminopeptidase N (APN) and DPP-IV activities, reduced cell viability and increased DNA fragmentation, suggesting induction of apoptosis. Since bacitracin and bestatin are already marketed drugs, studying in depth the molecular mechanisms underlying their effects on melanoma cells is warranted. Additionally, bestatin emerges as a new lead compound for the development of DPP-IV inhibitors, and a promising dual APN/DPP-IV inhibitor for the treatment of pathologies in which both enzymes are upregulated.

Performance and intestinal microbiota of chickens receiving probiotic in the feed and submitted to antibiotic therapy.

The purpose of this study was to verify the ability of a probiotic in the feed to maintain the stability of the gut microbiota in chickens after antibiotic therapy and its association with growth performance. One thousand six hundred twenty 1-day-old Cobb male were housed in floor pens (36 pens, 45 birds/pen) and were fed corn-/soya bean meal-based diets supplemented with or without probiotic (Bacillus subtilis) during the entire rearing phase. From 21 to 24 days of age (three consecutive days), the chickens were submitted to antibiotic therapy via drinking water (bacitracin and neomycin) in order to mimic a field treatment and induce dysbiosis. Growth performance was monitored until 42 days of age. At 2, 4 and 6 days after antibiotic therapy, three chickens from each pen were euthanized and the contents of the small intestine and caeca were collected and pooled. The trial was conducted with four treatments and nine replicates in a 2 × 2 factorial arrangement for performance characteristics (with and without probiotic × with and without antibiotic therapy); for the intestinal microbiota, it was in a 2 × 2 × 3 factorial arrangement (with and without probiotic × with and without antibiotic therapy × 2, 4 and 6 days after the antibiotic therapy) with three replicates per treatment. Terminal restriction length polymorphism (T-RFLP) analysis showed that the structure of gut bacterial community was shaped by the intestinal segment and by the time after the antibiotic therapy. The number of 16S rDNAs copies in caecum contents decreased with time after the therapeutic treatment. The antibiotic therapy and dietary probiotic supplementation decreased richness and diversity indexes in the caecal contents. The improved performance observed in birds supplemented with probiotic may be related to changes promoted by the feed additive in the structure of the intestinal bacterial communities and phylogenetic groups. Antibiotic therapy modified the bacterial structure, but did not cause loss of broiler performance.

Tannins and Bacitracin Differentially Modulate Gut Microbiota of Broiler Chickens.

Antibiotic growth promoters have been used for decades in poultry farming as a tool to maintain bird health and improve growth performance. Global concern about the recurrent emergence and spreading of antimicrobial resistance is challenging the livestock producers to search for alternatives to feed added antibiotics. The use of phytogenic compounds appears as a feasible option due to their ability to emulate the bioactive properties of antibiotics. However, detailed description about the effects of in-feed antibiotics and alternative natural products on chicken intestinal microbiota is lacking. High-throughput sequencing of 16S rRNA gene was used to study composition of cecal microbiota in broiler chickens supplemented with either bacitracin or a blend of chestnut and quebracho tannins over a 30-day grow-out period. Both tannins and bacitracin had a significant impact on diversity of cecal microbiota. Bacitracin consistently decreased Bifidobacterium while other bacterial groups were affected only at certain times. Tannins-fed chickens showed a drastic decrease in genus Bacteroides while certain members of order Clostridiales mainly belonging to the families Ruminococcaceae and Lachnospiraceae were increased. Different members of these groups have been associated with an improvement of intestinal health and feed efficiency in poultry, suggesting that these bacteria could be associated with productive performance of birds.

Different antibiotic growth promoters induce specific changes in the cecal microbiota membership of broiler chicken.

Antimicrobials are sometimes given to food animals at low doses in order to promote faster growth. However, the mechanisms by which those drugs improve performance are not fully understood. This study aimed to investigate the impact of zinc bacitracin (55g/ton), enramycin (10g/ton); halquinol® (30g/ton); virginiamycin (16,5g/ton) and avilamycin (10g/ton) on the cecal microbiota of broiler chicken, compared to a control group. Six hundred and twenty four chicks (Cobb 500) arriving to an experimental unit were randomly assigned into each treatment with four repetitions per treatment. The cecal content of 16 animals per treatment (n = 96) was used for DNA extraction and sequencing of the V4 region of the 16S rRNA gene using Illumina technology. The use of antimicrobials induced significant changes in membership but not in structure of the cecal microbiota compared to the control group, suggesting a greater impact on the less abundant species of bacteria present in that environment. Halquinol was the only drug that did not affect microbial membership. Firmicutes comprised the major bacterial phylum present in the cecum of all groups. There was no statistical difference in relative abundances of the main phyla between treated animals and the control group (all P>0.05). Treatment with enramycin was associated with decreased richness and with lower relative abundance of unclassified Firmicutes, Clostridium XI, unclassified Peptostreptococcaceae (all P<0.001) and greater abundance of Clostridium XIVb (P = 0.004) and Anaerosporobacter spp. (P = 0.015), and treatment with bacitracin with greater relative abundance of Bilophila spp. (P = 0.004). Several bacterial genera were identified as representative of usage of each drug. This study used high throughput sequencing to characterize the impact of several antimicrobials in broiler chicken under controlled conditions and add new insights to the current knowledge on how AGPs affect the cecal microbiota of chicken.

Staphylococcus aureus resistance to topical antimicrobials in atopic dermatitis.

BACKGROUND:: Topical antimicrobial drugs are indicated for limited superficial pyodermitis treatment, although they are largely used as self-prescribed medication for a variety of inflammatory dermatoses, including atopic dermatitis. Monitoring bacterial susceptibility to these drugs is difficult, given the paucity of laboratory standardization. OBJECTIVE:: To evaluate the prevalence of Staphylococcus aureus topical antimicrobial drug resistance in atopic dermatitis patients. METHODS:: We conducted a cross-sectional study of children and adults diagnosed with atopic dermatitis and S. aureus colonization. We used miscellaneous literature reported breakpoints to define S. aureus resistance to mupirocin, fusidic acid, gentamicin, neomycin and bacitracin. RESULTS:: A total of 91 patients were included and 100 S. aureus isolates were analyzed. All strains were methicillin-susceptible S. aureus. We found a low prevalence of mupirocin and fusidic acid resistance (1.1% and 5.9%, respectively), but high levels of neomycin and bacitracin resistance (42.6% and 100%, respectively). Fusidic acid resistance was associated with more severe atopic dermatitis, demonstrated by higher EASI scores (median 17.8 vs 5.7, p=.009). Our results also corroborate the literature on the absence of cross-resistance between the aminoglycosides neomycin and gentamicin. CONCLUSIONS:: Our data, in a southern Brazilian sample of AD patients, revealed a low prevalence of mupirocin and fusidic acid resistance of S. aureus atopic eczema colonizer strains. However, for neomycin and bacitracin, which are commonly used topical antimicrobial drugs in Brazil, high levels of resistance were identified. Further restrictions on the use of these antimicrobials seem necessary to keep resistance as low as possible.

Staphylococcus aureus resistance to topical antimicrobials in atopic dermatitis

Abstract: Background: Topical antimicrobial drugs are indicated for limited superficial pyodermitis treatment, although they are largely used as self-prescribed medication for a variety of inflammatory dermatoses, including atopic dermatitis. Monitoring bacterial susceptibility to these drugs is difficult, given the paucity of laboratory standardization. Objective: To evaluate the prevalence of Staphylococcus aureus topical antimicrobial drug resistance in atopic dermatitis patients. Methods: We conducted a cross-sectional study of children and adults diagnosed with atopic dermatitis and S. aureus colonization. We used miscellaneous literature reported breakpoints to define S. aureus resistance to mupirocin, fusidic acid, gentamicin, neomycin and bacitracin. Results: A total of 91 patients were included and 100 S. aureus isolates were analyzed. All strains were methicillin-susceptible S. aureus. We found a low prevalence of mupirocin and fusidic acid resistance (1.1% and 5.9%, respectively), but high levels of neomycin and bacitracin resistance (42.6% and 100%, respectively). Fusidic acid resistance was associated with more severe atopic dermatitis, demonstrated by higher EASI scores (median 17.8 vs 5.7, p=.009). Our results also corroborate the literature on the absence of cross-resistance between the aminoglycosides neomycin and gentamicin. Conclusions: Our data, in a southern Brazilian sample of AD patients, revealed a low prevalence of mupirocin and fusidic acid resistance of S. aureus atopic eczema colonizer strains. However, for neomycin and bacitracin, which are commonly used topical antimicrobial drugs in Brazil, high levels of resistance were identified. Further restrictions on the use of these antimicrobials seem necessary to keep resistance as low as possible.

Additive antibiotic, probiotic and prebiotic for early weaned piglets / Aditivos antibiótico, probiótico e prebiótico em rações para leitões desmamados precocemente

The objective of this study was to evaluate the addition of the prebiotic mannan oligosaccharide (MOS 0.2%), probiotic (Bacillus subtilis 30g/ton) and antibiotic (Bacitracin zinc 125g/ton) to piglets feed in the post-weaning phase. Eighty (Danbread x Agroceres) pigs were used, that is, 40 males and 40 females, with initial weight of 7.1 ± 0.0175 kg. A randomized block design was used with four treatments and five replicates: 1 - Control; 2 - Prebiotic; 3 - Probiotic; 4 - Antibiotic. The variables evaluated were average daily gain (ADG), daily feed intake (DFI), feed conversion (FC) fecal consistency and leukocyte count. At 43 days of age, the animals presented the same weight gain (P> 0.05); however, there was increased intake of the diet containing prebiotic (P> 0.05), and feed conversion was better for control diet (P 0 05). In the period of 54 days of age of the animals, there were no differences in daily weight gain (P> 0.05), daily feed intake (P> 0.05) and feed conversion (P> 0.05), and also no differences in fecal consistency (P> 0.05). The number of leukocytes increased at 32 days of age when the diets containing prebiotics and probiotics were used (P> 0.05). The diet containing prebiotics increased the number of monocytes (P 0.05), and the diet containing antibiotic provided greater number of basophiles (P 0.05) at 36 days of age. The number of lymphocytes was not altered by the experimental diets (P> 0.05), the diets promoted no changes in the immunoglobulins IgA, IgM and IgG (P> 0.05). The use of prebiotics, probiotics and antibiotics did not influence the animals' performance from 22 to 54 days of age

Objetivou-se avaliar a adição do prebiótico mananoligossacarídeo (MOS 0,2%), probiótico (Bacillus subtilis 30g/tonelada) e antibiótico (bacitracina de zinco 125g/tonelada) em rações para leitões na fase de creche. Utilizaram-se 80 leitões (Danbread x Agroceres), sendo 40 machos e 40 fêmeas, com peso inicial de 7,1±0,0175kg, distribuídos em delineamento de blocos ao acaso, com quatro tratamentos e cinco repetições: 1 - controle; 2 - prebiótico; 3 probióticos; e 4 - antibiótico. As variáveis avaliadas foram ganho de peso diário (GPD), consumo de ração diário (CRD), conversão alimentar (CA), consistência fecal e leucometria global. Aos 43 dias de idade, os animais apresentaram o mesmo ganho de peso (P>0,05), porém, a dieta contendo prebiótico aumentou o consumo (P>0,05); a conversão alimentar foi melhor na dieta controle (P 0,05). No período de 54 dias de idade dos animais, não houve diferença para ganho de peso diário (P>0,05), consumo de ração diário (P>0,05) e conversão alimentar (P>0,05). Não houve diferença para consistência fecal (P>0,05). O número  de leucócitos aumentou aos 32 dias de idade, quando as dietas contendo prebióticos e probióticos foram utilizadas (P>0,05). A ração contendo prebiótico aumentou o número de monócitos (P 0,05) e a dieta contendo antibiótico proporcionou maior número de basófilos (P 0,05), aos 36 dias de idade dos animais; o número de linfócitos não foi alterado pelas dietas experimentais (P>0,05). As dietas não promoveram alterações nas imunoglobulinas IgA, IgM e IgG (P>0,05). Conclui-se que o uso de prebióticos, probióticos e antibióticos não influenciou o desempenho dos animais dos 22 aos 54 dias de idade

Additive antibiotic, probiotic and prebiotic for early weaned piglets / Aditivos antibiótico, probiótico e prebiótico em rações para leitões desmamados precocemente

The objective of this study was to evaluate the addition of the prebiotic mannan oligosaccharide (MOS 0.2%), probiotic (Bacillus subtilis 30g/ton) and antibiotic (Bacitracin zinc 125g/ton) to piglets feed in the post-weaning phase. Eighty (Danbread x Agroceres) pigs were used, that is, 40 males and 40 females, with initial weight of 7.1 ± 0.0175 kg. A randomized block design was used with four treatments and five replicates: 1 - Control; 2 - Prebiotic; 3 - Probiotic; 4 - Antibiotic. The variables evaluated were average daily gain (ADG), daily feed intake (DFI), feed conversion (FC) fecal consistency and leukocyte count. At 43 days of age, the animals presented the same weight gain (P> 0.05); however, there was increased intake of the diet containing prebiotic (P> 0.05), and feed conversion was better for control diet (P 0 05). In the period of 54 days of age of the animals, there were no differences in daily weight gain (P> 0.05), daily feed intake (P> 0.05) and feed conversion (P> 0.05), and also no differences in fecal consistency (P> 0.05). The number of leukocytes increased at 32 days of age when the diets containing prebiotics and probiotics were used (P> 0.05). The diet containing prebiotics increased the number of monocytes (P 0.05), and the diet containing antibiotic provided greater number of basophiles (P 0.05) at 36 days of age. The number of lymphocytes was not altered by the experimental diets (P> 0.05), the diets promoted no changes in the immunoglobulins IgA, IgM and IgG (P> 0.05). The use of prebiotics, probiotics and antibiotics did not influence the animals' performance from 22 to 54 days of age(AU)

Objetivou-se avaliar a adição do prebiótico mananoligossacarídeo (MOS 0,2%), probiótico (Bacillus subtilis 30g/tonelada) e antibiótico (bacitracina de zinco 125g/tonelada) em rações para leitões na fase de creche. Utilizaram-se 80 leitões (Danbread x Agroceres), sendo 40 machos e 40 fêmeas, com peso inicial de 7,1±0,0175kg, distribuídos em delineamento de blocos ao acaso, com quatro tratamentos e cinco repetições: 1 - controle; 2 - prebiótico; 3 probióticos; e 4 - antibiótico. As variáveis avaliadas foram ganho de peso diário (GPD), consumo de ração diário (CRD), conversão alimentar (CA), consistência fecal e leucometria global. Aos 43 dias de idade, os animais apresentaram o mesmo ganho de peso (P>0,05), porém, a dieta contendo prebiótico aumentou o consumo (P>0,05); a conversão alimentar foi melhor na dieta controle (P 0,05). No período de 54 dias de idade dos animais, não houve diferença para ganho de peso diário (P>0,05), consumo de ração diário (P>0,05) e conversão alimentar (P>0,05). Não houve diferença para consistência fecal (P>0,05). O número  de leucócitos aumentou aos 32 dias de idade, quando as dietas contendo prebióticos e probióticos foram utilizadas (P>0,05). A ração contendo prebiótico aumentou o número de monócitos (P 0,05) e a dieta contendo antibiótico proporcionou maior número de basófilos (P 0,05), aos 36 dias de idade dos animais; o número de linfócitos não foi alterado pelas dietas experimentais (P>0,05). As dietas não promoveram alterações nas imunoglobulinas IgA, IgM e IgG (P>0,05). Conclui-se que o uso de prebióticos, probióticos e antibióticos não influenciou o desempenho dos animais dos 22 aos 54 dias de idade(AU)

Enterotoxin-Encoding Genes in Staphylococcus spp. from Food Handlers in a University Restaurant.

Food handlers carrying enterotoxin-producing Staphylococcus are a potential source of food poisoning. The aim of this study was to analyze genes encoding enterotoxins in coagulase-positive Staphylococcus (CoPS) and coagulase-negative Staphylococcus (CoNS) isolated from the anterior nostrils and hands of food handlers at a university restaurant in the city of Natal, Northeast Brazil. Thirty food handlers were screened for the study. The isolates were subjected to Gram staining, a bacitracin sensitivity test, mannitol fermentation, and catalase and coagulase tests. CoNS and CoPS strains were subsequently identified by a Vitek 2 System (BioMerieux, France) and various biochemical tests. Polymerase chain reaction was used to detect genes for enterotoxins A, B, C, D, E, G, H, and I (sea, seb, sec, sed, see, seg, seh, and sei) and a disc-diffusion method was used to determine susceptibility to several classes of antimicrobials. All food handlers presented staphylococci on their hands and/or noses. The study found 58 Staphylococcus spp., of which 20.7% were CoPS and 79.3% were CoNS. S. epidermidis was the most prevalent species. Twenty-nine staphylococci (50%) were positive for one or more enterotoxin genes, and the most prevalent genes were seg and sei, each with a frequency of 29.3%. Indeed, CoNS encoded a high percentage of enterotoxin genes (43.5%). However, S. aureus encoded even more enterotoxin genes (75%). Most isolates showed sensitivity to the antibiotics used for testing, except for penicillin (only 35% sensitive). The results from this study reinforce that coagulase-negative as well as coagulase-positive staphylococci isolated from food handlers are capable of genotypic enterotoxigenicity.

Antimicrobial activity of different filling pastes for deciduous tooth treatment.

Guedes-Pinto paste is the filling material most employed in Brazil for endodontic treatment of deciduous teeth; however, the Rifocort® ointment has been removed. Thus, the aim of this study was to investigate the antimicrobial potential of filling pastes, by proposing three new pharmacological associations to replace Rifocort® ointment with drugs of already established antimicrobial power: Nebacetin® ointment, 2% Chlorhexidine Gluconate gel, and Maxitrol® ointment. A paste composed of Iodoform, Rifocort® ointment and Camphorated Paramonochlorophenol (CPC) was employed as the gold standard (G1). The other associations were: Iodoform, Nebacetin® ointment and CPC (G2); Iodoform, 2% Chlorhexidine Digluconate gel and CPC (G3); Iodoform, Maxitrol® ointment and CPC (G4). The associations were tested for Staphylococcus aureus (S. aureus), Streptococcus mutans (S. mutans), Streptococcus oralis (S. oralis), Enterococcus faecalis (E. faecalis), Escherichia coli (E. coli), and Bacillus subtilis (B. subtilis), using the methods of dilution on solid medium - orifice agar - and broth dilution. The results were tested using statistical analysis ANOVA and Kruskal-Wallis. They showed that all the pastes had a bacteriostatic effect on all the microorganisms, without any statistically significant difference, compared with G1. S. aureus was statistically significant (multiple comparison test of Tukey), insofar as G2 and G3 presented the worst and the best performance, respectively. All associations were bactericidal for E. coli, S. aureus, S. mutans and S. oralis. Only G3 and G4 were bactericidal for E. faecalis, whereas no product was bactericidal for B. subtilis. Thus, the tested pastes have antimicrobial potential and have proved acceptable for endodontic treatment of primary teeth.

Antimicrobial activity of different filling pastes for deciduous tooth treatment

Guedes-Pinto paste is the filling material most employed in Brazil for endodontic treatment of deciduous teeth; however, the Rifocort® ointment has been removed. Thus, the aim of this study was to investigate the antimicrobial potential of filling pastes, by proposing three new pharmacological associations to replace Rifocort® ointment with drugs of already established antimicrobial power: Nebacetin® ointment, 2% Chlorhexidine Gluconate gel, and Maxitrol® ointment. A paste composed of Iodoform, Rifocort® ointment and Camphorated Paramonochlorophenol (CPC) was employed as the gold standard (G1). The other associations were: Iodoform, Nebacetin® ointment and CPC (G2); Iodoform, 2% Chlorhexidine Digluconate gel and CPC (G3); Iodoform, Maxitrol® ointment and CPC (G4). The associations were tested for Staphylococcus aureus (S. aureus), Streptococcus mutans (S. mutans), Streptococcus oralis (S. oralis), Enterococcus faecalis (E. faecalis), Escherichia coli (E. coli), and Bacillus subtilis (B. subtilis), using the methods of dilution on solid medium – orifice agar – and broth dilution. The results were tested using statistical analysis ANOVA and Kruskal-Wallis. They showed that all the pastes had a bacteriostatic effect on all the microorganisms, without any statistically significant difference, compared with G1. S. aureus was statistically significant (multiple comparison test of Tukey), insofar as G2 and G3 presented the worst and the best performance, respectively. All associations were bactericidal for E. coli, S. aureus, S. mutans and S. oralis. Only G3 and G4 were bactericidal for E. faecalis, whereas no product was bactericidal for B. subtilis. Thus, the tested pastes have antimicrobial potential and have proved acceptable for endodontic treatment of primary teeth.

Níveis da bacitracina de zinco como melhorador do desempenho de frangos de corte / Levels of zinc bacitracin used to improve the performance of broilers

A utilização de antimicrobianos melhoradores de desempenho na criação de frangos de corte é uma prática comum na indústria avícola e, no Brasil, seu uso deve ser feito de acordo com os limites determinados pelo Ministério da Agricultura Pecuária e Abastecimento (MAPA).Objetivou-se com o presente trabalho determinar o efeito da utilização da bacitracina de zinco, dentro dos níveis recomendados pelo Ministério da Agricultura Pecuária e Abastecimento (MAPA), em dietas para frangos de corte sobre o desempenho de aves e criadas de 1 a 42 dias de idade. Utilizou-se o delineamento inteiramente casualizado, com 5 tratamentos, distribuídos em 10 repetições de 25 pintos machos de corte da linhagem Cobb 500®, totalizando 1250 aves. Os tratamentos experimentais foram constituídos de cinco níveis de inclusão de bacitracina de zinco (0, 10, 25, 40 e 55ppm). As variáveis analisadas foram consumo de ração, ganho de peso, conversão alimentar e avaliação econômica das dietas. Para o período total de criação, avaliou-se também a viabilidade dos frangos de corte. A bacitracina de zinco foi eficiente como beneficiador do desempenho de frangos de corte criados no período de 1 a 21, 1 a 35 e 1 a 42 dias. Para o período de 1 a 21 dias, o uso de 55 e 29,3ppm de bacitracina de zinco resultou em menor consumo de ração e maior ganho de peso, respectivamente. No geral, a melhor conversão alimentar foi obtida quando se adicionou 55ppm de bacitracina de zinco na ração de frangos de corte.(AU)

The use of growth promoters in the broilers production is a common practice in the poultry industry and its use must be made accordance with limits in Brazil set by the Ministry of Agriculture, Livestock and Supply (MAPA).The main objective of this study was to verify the effect of the use of zinc bacitracin, within the levels recommended by the Brazilian Ministry of Agriculture, Livestock and Food Supply (MAPA), in broiler diets for the performance of birds from 1 to 42 days old. We used a randomized design with five treatments in 10 replications of 25 male chicks from Cobb cut 500®, totaling 1250 birds. The treatments consisted of five inclusion levels of zinc bacitracin (0, 10, 25, 40 and 55ppm). The variables studied were feed intake, weight gain, feed conversion and economic evaluation of feed. For the breeding period as a whole, this study also evaluated the viability of broilers. Zinc bacitracin was effective as growth promoter of broilers reared during 1 to 21, 1 to 35 and 1 to 42 days. For the period 1-21 days, using 55 and 29.3ppm of zinc bacitracin resulted in a lower feed intake and increased weight gain, respectively. In general, the best feed conversion was obtained when 55ppm of zinc bacitracin was added to the feed of broilers.(AU)