Molecular diversity of Staphylococcus aureus and the role of milking equipment adherences or biofilm as a source for bulk tank milk contamination.

Staphylococcus aureus is one of the most frequent pathogens causing intramammary infections in dairy herds. Consequently, virulence factors, pathobiology, and epidemiology of Staphylococcus aureus strains have been widely assessed through the years. Nevertheless, not much has been described about the epidemiology of Staph. aureus strains from bulk tank milk (BTM) and adherences on milking equipment (AMES), even when these strains may play a role in the quality of milk that is intended for human consumption. The objective of this study was to assess the strain diversity of 166 Staph. aureus isolates collected from 3 consecutive BTM samples, and from AMES in contact with milk from 23 Chilean dairy farms. Isolates were analyzed and typed using pulsed-field gel electrophoresis. Diversity of strains, both within and among farms, was assessed using Simpson's index of diversity (SID). On farms where Staph. aureus was isolated from both AMES and BTM (n = 8), pulsotypes were further analyzed to evaluate the role of AMES as a potential source of Staph. aureus strains in BTM. Among all Staph. aureus analyzed by pulsed-field gel electrophoresis, a total of 42 pulsotypes (19 main pulsotypes and 23 subtypes) were identified. Among dairy farms, strain diversity was highly heterogeneous (SID = 0.99). Within dairy farms, Staph. aureus strain diversity was variable (SID = 0 to 1), and 18 dairy operations (81.8%) had one pulsotype that was shared between at least 2 successive BTM samples. In those farms where Staph. aureus was isolated in both AMES and BTM (n = 8), 7 (87.5%) showed a clonal distribution of Staph. aureus strains between these 2 types of samples. The overlapping of certain Staph. aureus strains among dairy farms may point out common sources of Staph. aureus among otherwise epidemiologically unrelated farms. Indistinguishable Staph. aureus strains between AMES and BTM across dairy farms suggest that Staph. aureus-containing AMES may represent a source for BTM contamination, thus affecting milk quality. Our study highlights the role of viable Staph. aureus in AMES as a source for BTM contamination on dairy farms, and also describes the overlapping and presence of specific BTM and AMES pulsotypes among farms.

Biotechnological potential of an exo-polygalacturonase of the new strain Penicillium janthinellum VI2R3M: biochemical characterization and clarification of fruit juices.

AIMS: The aim of this work was to characterize and apply a polygalacturonase of Penicillium janthinellum new strain VI2R3M. METHODS AND RESULTS: The polygalacturonase obtained from P. janthinellum VI2R3M was incubated in cultures of passion fruit peel and was partially purified by ion-exchange chromatography and gel filtration. The enzyme showed a relative molecular mass of 102·0 kDa, maximum activity at pH 5·0, temperature of 50°C, 100% stablity at 50°C and 80% stablity at pH 3·0-5·0. The apparent Km , Vmax and Kcat values for hydrolyzing polygalacturonic acid were 2·56 mg ml-1 , 163·1 U mg-1 and 277 s-1 respectively. The polygalacturonase presented exo activity and was activated by Mg2+ . The juices treated with polygalacturonase presented increases in transmittance with reduction in colour. CONCLUSIONS: The results suggest that the new lineage P. janthinellum VI2R3M presents a high yield of an exo-polygalacturonase induced by agro-industrial residues, with excellent activity and stability in acidic pH and at 50°C. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of agro-industrial residue to obtain the polygalacturonase can contribute to a decrease enzyme production cost. The results of the activity, stability to acidic pH and excellent performance in the clarification of juices show that the enzyme is promising for industrial application.

Species distribution, sequence types and antimicrobial resistance of Acinetobacter spp. from cystic fibrosis patients.

Acinetobacter spp. are important healthcare pathogens, being closely linked to antibiotic resistance and outbreaks worldwide. Although such species are rarely observed in patients with cystic fibrosis (CF), we describe the characteristics of 53 strains of Acinetobacter spp. isolated from the sputum of 39 Brazilian patients with CF. The species distribution was A. baumannii (n = 29), A. pittii (n = 13), A. nosocomialis (n = 8), A. seifertii (n = 1), A. soli (n = 1) and A. variabilis (n = 1) determined by partial rpoB gene sequencing. Sixteen strains (10 A. baumannii, 3 A. pittii and 3 A. nosocomialis) were multidrug-resistant (MDR) by disk diffusion test (30%) and eight MDR carbapenem-resistant A. baumannii strains harboured the bla OXA-23-like oxacillinase gene. Thirty-three sequence types (STs) were identified by multilocus sequence typing of which eight were novel (A. baumannii: 843, 844, 845, 847, 848; A. pitti: 643; A. nosocomialis: 862 and A. seifertii: 846); six STs (2 A. baumannii, 3 A. pittii and 1 A. nosocomialis) were found in more than one patient. Four strains of A. baumannii were assigned to two common clonal complexes (CCs), namely, CC1 (ST1, ST20 and ST160), and CC79 (ST79). This study underlines the extensive species diversity of Acinetobacter spp. strains in CF lung infections which may present difficulties for therapy due to significant antimicrobial resistance.

Antimicrobial activity of an aspartic protease from Salpichroa origanifolia fruits.

Plant proteases play a fundamental role in several processes like growth, development and in response to biotic and abiotic stress. In particular, aspartic proteases (AP) are expressed in different plant organs and have antimicrobial activity. Previously, we purified an AP from Salpichroa origanifolia fruits called salpichroin. The aim of this work was to determine the cytotoxic activity of this enzyme on selected plant and human pathogens. For this purpose, the growth of the selected pathogens was analysed after exposure to different concentrations of salpichroin. The results showed that the enzyme was capable of inhibiting Fusarium solani and Staphylococcus aureus in a dose-dependent manner. It was determined that 1·2 µmol l-1 of salpichroin was necessary to inhibit 50% of conidial germination, and the minimal bactericidal concentration was between 1·9 and 2·5 µmol l-1 . Using SYTOX Green dye we were able to demonstrate that salpichroin cause membrane permeabilization. Moreover, the enzyme treated with its specific inhibitor pepstatin A did not lose its antibacterial activity. This finding demonstrates that the cytotoxic activity of salpichroin is due to the alteration of the cell plasma membrane barrier but not due to its proteolytic activity. Antimicrobial activity of the AP could represent a potential alternative for the control of pathogens that affect humans or crops of economic interest. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides insights into the antimicrobial activity of an aspartic protease isolated from Salpichroa origanifolia fruits on plant and human pathogens. The proteinase inhibited Fusarium solani and Staphylococcus aureus in a dose-dependent manner due to the alteration of the cell plasma membrane barrier but not due to its proteolytic activity. Antimicrobial activity of salpichroin suggests its potential applications as an important tool for the control of pathogenic micro-organisms affecting humans and crops of economic interest. Therefore, it would represent a new alternative to avoid the problems of environmental pollution and antimicrobial resistance.

Metagenomic study of bacterial microbiota in persistent endodontic infections using Next-generation sequencing.

AIM: To determine the bacterial microbiota in root canals associated with persistent apical periodontitis and their relationship with the clinical characteristics of patients using next-generation sequencing (NGS). METHODOLOGY: Bacterial samples from root canals associated with teeth having persistent apical periodontitis were taken from 24 patients undergoing root canal retreatment. Bacterial DNA was extracted, and V3-V4 variable regions of the 16S rRNA gene were amplified. The amplification was deep sequenced by Illumina technology to establish the metagenetic relationships among the bacterial species identified. The composition and diversity of microbial communities in the root canal and their relationships with clinical features were analysed. Parametric and nonparametric tests were used to analyse differences between patient characteristics and microbial data. RESULTS: A total of 86 different operational taxonomic units (OTUs) were identified and Good's nonparametric coverage estimator method indicated that 99.9 ± 0.00001% diversity was recovered per sample. The largest number of bacteria belonged to the phylum Proteobacteria. According to the medical history from the American Society of Anesthesiologists (ASA) Classification System, ASA II-III had higher richness estimates and distinct phylogenetic relationships compared to ASA I individuals (P < 0.05). Periapical index (PAI) score 5 was associated with increased microbiota diversity in comparison to PAI score 4, and this index was reduced in symptomatic patients. CONCLUSIONS: Based on the findings of this study, it is possible to suggest a close relationship between several clinical features and greater microbiota diversity with persistent endodontic infections. This work provides a better understanding on how microbial communities interact with their host and vice versa.

Morbidity, fertility and pregnancy outcomes after myoma enucleation by laparoscopy versus laparotomy.

OBJECTIVES: Myomas are defined as benign tumours that arise from smooth muscle cells of the uterus. Clinically, they are found in 5-77% of women of reproductive age. The prevalence rate varies considerably in the literature and a large number of fibroids do not cause symptoms. The lifetime risk of acquiring myomas is 70% for Caucasian women and ≥ 80% for African American women. MATERIALS/METHODS: The data of 265 patients undergoing surgery for symptomatic myomas by laparoscopy or laparotomy, performed in the gynaecological department of Hannover Medical School, Hannover, Germany, between 2009 and 2013, were retrospectively analysed in this retrospective design study. RESULTS: High pregnancy rates (up to 70%) and birth rates (up to 86%) after myomectomy, regardless of the surgical approach adopted, were found in the current study. The trend was that ≥ 3 myomas and those that were ≥ 6 cm in size were almost always removed by laparotomy in our clinic. It was possible to remove up to 42 myomas without having to perform a hysterectomy. A statistically significant negative correlation was observed in relation to the association between the size of the largest myoma extracted and the pregnancy rate (p = 0.02). A statistically significant correlation between the number of removed myomas and the pregnancy rate was observed for patients who wished to bear children (p = 0.010). Elevated complication rates (of up to 50%) were reported for more than three extracted myomas with a statistically significance (p = 0.0471). CONCLUSIONS: It is necessary to ensure sound preoperative selection of the surgical approach in order to achieve the most optimal results, especially for those patients who wished to bear children.

Prospective, randomized and controlled study of mesh displacement after laparoscopic inguinal repair: fixation versus no fixation of mesh.

INTRODUCTION: Repair of inguinal hernia is one of the most common elective operations performed in general surgery practice. Mesh hernia repair became the gold standard because of its low recurrence rate in comparison with non-tension-free repair. Laparoscopic approach seems to have potential advantages over open techniques, including faster recovery and reduced acute and chronic pain rate. Laparoscopic mesh fixation is usually performed using staples, which is associated with higher cost and risk for chronic pain. Recently, the role of mesh fixation has been questioned by several surgeons. AIM: To evaluate mesh displacement in patients undergoing laparoscopic inguinal hernia repair comparing mesh fixation with no fixation. METHODS: From January 2012 to May 2014, 60 consecutive patients with unilateral inguinal hernia were randomized into two groups: control group--10 patients underwent totally extraperitoneal (TEP) repair with mesh fixation; NO FIX group-50 patients underwent TEP repair with no mesh fixation. Mesh was marked with three 3-mm surgical clips at its medial inferior, medial superior and lateral inferior corners. Mesh displacement was measured by comparing an initial X-ray, performed in the immediate postoperative period, with a second X-ray obtained 30 days later. RESULTS: The mean displacement of all three clips in control group was 0.1-0.35 cm (range 0-1.2 cm), while in NO FIX group was 0.1-0.3 cm (range 0-1.3 cm). The overall displacement of control and NO FIX group did not show any difference (p = 0.50). CONCLUSION: Fixation of the mesh for TEP repair is unnecessary. TEP repair with no mesh fixation is safe and is not associated with increased risk of mesh displacement.

Identification and mapping of resistance genes to Phakopsora pachyrhizi in soybean (Glycine max L.) accession PI 594767-A.

The goal of this study was to study resistance inheritance in the soybean (Glycine max L.) accession PI 594767-A to the Phakopsora pachyrhizi isolate PPUFV02, and map the resistance gene(s) identified using microsatellite markers. Crosses between PI 594767-A and the susceptible cultivar 'Conquista' gave rise to the segregating subpopulations 26C-2 and 26C-5, which in the F2 generation were evaluated for their reactions to PPUFV02. In addition, analyses with microsatellite markers linked to the Rpp1-Rpp5 loci were also performed. The segregation pattern obtained in 26C-2 revealed that resistance was governed by a recessive gene; a 1:2:1 segregation pattern was observed in 26C-5, indicating control by a gene with partial dominance. This variability may have been caused because environmental conditions, particularly temperature, when 26C-5 was assessed were unfavorable for pathogen development, allowing the phenotypic expression of heterozygous alleles in PI 594767-A. A resistance gene was located in the soybean linkage group G, in the genomic region between Sct_187r2 and Sat_064 that contains the Rpp1 locus. Resistance in PI 594767-A is probably conferred by a new Rpp1 gene allele, because this accession has a haplotype for Sct_187r2 and Sat_064, which differs from haplotypes of accessions that also contain resistance alleles that map the Rpp1 locus. The use of Sct_187r2 and Sat_064 will facilitate the introgression of the resistance allele from PI 594767-A and its pyramiding with other resistance genes into genotypes with superior agronomic characteristics, in order to obtain cultivars with broad-spectrum resistance to P. pachyrhizi.

Emissions from the combustion of eucalypt and pine chips in a fluidized bed reactor.

Interest in renewable energy sources has increased in recent years due to environmental concerns about global warming and air pollution, reduced costs and improved efficiency of technologies. Under the European Union (EU) energy directive, biomass is a suitable renewable source. The aim of this study was to experimentally quantify and characterize the emission of particulate matter (PM2.5) resulting from the combustion of two biomass fuels (chipped residual biomass from pine and eucalypt), in a pilot-scale bubbling fluidized bed (BFB) combustor under distinct operating conditions. The variables evaluated were the stoichiometry and, in the case of eucalypt, the leaching of the fuel. The CO and PM2.5 emission factors were lower when the stoichiometry used in the experiments was higher (0.33±0.1 g CO/kg and 16.8±1.0 mg PM2.5/kg, dry gases). The treatment of the fuel by leaching before its combustion has shown to promote higher PM2.5 emissions (55.2±2.5 mg/kg, as burned). Organic and elemental carbon represented 3.1 to 30 wt.% of the particle mass, while carbonate (CO3(2-)) accounted for between 2.3 and 8.5 wt.%. The particulate mass was mainly composed of inorganic matter (71% to 86% of the PM2.5 mass). Compared to residential stoves, BFB combustion generated very high mass fractions of inorganic elements. Chloride was the water soluble ion in higher concentration in the PM2.5 emitted by the combustion of eucalypt, while calcium was the dominant water soluble ion in the case of pine.

Evaluation of Acid Digestion Procedures to Estimate Mineral Contents in Materials from Animal Trials.

Rigorously standardized laboratory protocols are essential for meaningful comparison of data from multiple sites. Considering that interactions of minerals with organic matrices may vary depending on the material nature, there could be peculiar demands for each material with respect to digestion procedure. Acid digestion procedures were evaluated using different nitric to perchloric acid ratios and one- or two-step digestion to estimate the concentration of calcium, phosphorus, magnesium, and zinc in samples of carcass, bone, excreta, concentrate, forage, and feces. Six procedures were evaluated: ratio of nitric to perchloric acid at 2:1, 3:1, and 4:1 v/v in a one- or two-step digestion. There were no direct or interaction effects (p>0.01) of nitric to perchloric acid ratio or number of digestion steps on magnesium and zinc contents. Calcium and phosphorus contents presented a significant (p<0.01) interaction between sample type and nitric to perchloric acid ratio. Digestion solution of 2:1 v/v provided greater (p<0.01) recovery of calcium and phosphorus from bone samples than 3:1 and 4:1 v/v ratio. Different acid ratios did not affect (p>0.01) calcium or phosphorus contents in carcass, excreta, concentrate, forage, and feces. Number of digestion steps did not affect mineral content (p>0.01). Estimated concentration of calcium, phosphorus, magnesium, and zinc in carcass, excreta, concentrated, forage, and feces samples can be performed using digestion solution of nitric to perchloric acid 4:1 v/v in a one-step digestion. However, samples of bones demand a stronger digestion solution to analyze the mineral contents, which is represented by an increased proportion of perchloric acid, being recommended a digestion solution of nitric to perchloric acid 2:1 v/v in a one-step digestion.

Generalization to d-dimensions of a fermionic path integral for exact enumeration of polygons on hypercubic lattices.

The generating function for polygons on the square lattice has been known for many decades and is closely related to the path integral formulation of a free fermion model. On the cubic and hypercubic lattices the generating function is still unknown and the problem remains open. It has been conjectured that the three-dimensional (3D) and higher dimensional problems are not solvable-or, to be more precise, that there are no differentiably finite (D-finite) solutions. In this context, very recently a Berezin integral of an exponentiated Grassmann action was found for the polygon generating function on the cubic lattice, making explicit the connection between 3D polygons and a model of interacting fermions. Here we address the problem of how to generalize the 3D result to higher dimensions. We derive a Grassmann representation in terms of a Berezin integral for the generating function of polygons on d-dimensional hypercubic lattices. On the one hand, this new result admittedly brings us no closer to the problem of finding an explicit analytic expression for the desired generating function for polygons. On the other hand, however, the significant advance reported here precisely quantifies the remarkable mathematical difficulty of finding the explicit generating function. Indeed, the non-quadratic functional form of the Grassmann action that we derive here provides a very clear picture of the formidable mathematical obstruction that would need to be overcome. Specifically, in d dimensions, the Grassmann action contains terms of degree 2 ( d - 1 ) , so the model describes interacting rather than free fermions. It is an open problem whether or not these models of interacting fermions can in principle be free fermionized through some still undiscovered algebraic method, but it is widely believed that this goal is mathematically impossible.

Fetal inflammatory response syndrome predicts early-onset sepsis and cystic periventricular leukomalacia in preterm neonates: A retrospective study.

BACKGROUND: Fetal inflammatory response syndrome (FIRS), the fetal equivalent of chorioamnionitis, is associated with poorer neonatal outcomes. FIRS is diagnosed through placental histology, namely by the identification of funisitis (inflammation of the umbilical cord) and chorionic vasculitis (inflammation of fetal vessels within the chorionic plate). The aim of this study was to identify and evaluate associations between FIRS and neonatal outcomes in preterm neonates. METHODS: We performed a retrospective cohort study at a level III neonatal intensive care unit (NICU), from January 1st 2008 to December 31st 2022, involving all inborn neonates with a gestational age below 30 weeks. We compared preterm neonates based on whether their placental histology described funisitis with chorionic vasculitis (FCV) or not. RESULTS: The study included 113 preterms, 27 (23.9%) of those had FCV and 86 (76.1%) did not. After adjusting to gestational age, prolonged rupture of membranes and preeclampsia, FCV was independently associated with the development of early-onset sepsis (OR = 7.3, p = 0.021) and cystic periventricular leukomalacia (OR = 4.6, p = 0.004). CONCLUSION: The authors identified an association between FIRS and the development of early-onset sepsis and cystic periventricular leukomalacia, highlighting the importance of early detection and management of this condition in order to improve long-term neonatal outcomes.

Metabolic Syndrome and Positive Frailty Screening: A Cross-Sectional Study with Community-Dwelling Older Adults.

Background: Metabolic Syndrome is a set of disorders that characterized by the association of three or more risk factors, like the obesity central, dyslipidemia, borderline blood pressure, hyperglycemia, and the increase of triglycerides. However, these factors also can be associated with pathophysiology of frailty. Objectives: verifying whether the metabolic syndrome is associated to the positive frailty screening in the older people. Design: Cross-sectional study. Participants: 443 older people living in Rio Branco, Brazil. Setting: Data collection was carried out in two stages: a personal interview and blood collection. Measurements: The diagnosis of metabolic syndrome was based on the criteria of the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults. The frailty screening was performed using subjective questions validated in a previous study. Descriptive statistics and multinomial logistic regression were used for data analyses. Results: There was a predominance of female older people (69.07%), aged between 60 and 79 years (87.13%), with an income greater than or equal to one minimum wage (72.09%), no cognitive decline (75.94%) and depressive symptoms (63.31%), independent for BADL (86.46%) and dependent for IADL (51.69%). From the total sample, 56.88% of the older people were identified as frail, 34.09% pre-frail and 9.03% non frail. The prevalence of metabolic syndrome was 51.69%. After adjusting by the independent variables, an association between metabolic syndrome and pre-frailty was observed, and older people with metabolic syndrome were more likely to be prefrail (RRR=2.36; 95%CI=1.08-5.18). Conclusion: The metabolic syndrome was associated to the increase chance of screening for prefrailty in the older people evaluated, which reinforces the needy to establish preventive measures in relation to the metabolic syndrome to avoid frailty in the older people.

Biocidal effects of organometallic materials supported on ZSM-5 Zeolite: Influence of the physicochemical and surface properties.

Antifouling coatings containing biocidal agents can be used to prevent the accumulation of biotic deposits on submerged surfaces; however, several commercial biocides can negatively affect the ecosystem. In this study, various formulations of a potential biocide product comprising copper nanoparticles and capsaicin supported on zeolite ZSM-5 were analyzed to determine the influence of the concentration of each component. The incorporation of copper was evidenced by scanning electron microscopy and energy dispersive spectroscopy. Similarly, Fourier-transform infrared spectroscopy confirmed that capsaicin was supported on the zeolite surface. The presence of capsaicin on the external zeolite surface significantly reduced the surface area of the zeolite. Finally, bacterial growth inhibition analysis showed that copper nanoparticles inhibited the growth of strains Idiomarina loihiensis UCO25, Pseudoalteromonas sp. UCO92, and Halomonas boliviensis UCO24 while the organic component acted as a reinforcing biocide.

Resistance exercise training does not affect plasma irisin levels of hemodialysis patients.

Irisin, a hormone secreted by myocytes induced in exercise, acts as a muscle-derived energy-expenditure signal that binds to undetermined receptors on the white adipose tissue surface, stimulating its browning and uncoupling protein 1 (UCP1) expression. The purpose of this study was to assess the effect of an intradialytic resistance exercise training program (RETP) on plasma irisin levels of hemodialysis (HD) patients and compare the baseline plasma irisin levels of HD patients to healthy subjects. This longitudinal study enrolled 26 patients undergoing HD (50% men, 44.8±14.1 years, body mass index (BMI) 23.5±3.9 kg/m²). The healthy subjects group consisted of 11 women and 7 men with mean age of 50.9±6.6 years and BMI, 24.2±2.7 kg/m². Anthropometric and biochemistry parameters (Irisin by Enzyme-Linked Immunosorbent Assay) were measured at the baseline and after 6 months of RETP (in both lower limbs). There was no difference regarding gender, age, and BMI between HD patients and healthy subjects. Plasma irisin levels in HD patients were lower than in healthy subjects (71.0±41.6 vs. 101.3±12.5 ng/ml, p<0.05). Although the muscle mass increased in consequence of exercise [evaluated by arm muscle area from 27.9 (24.1) to 33.1 (19.0) cm²], plasma irisin did not differ significantly after exercises (71.0±41.6 vs. 73.3±36.0 ng/ml). HD patients seem to have lower plasma irisin when compared to healthy subjects. Moreover, a resistance exercise training program was unable to augment plasma irisin despite increasing muscle mass.

Chylous ascites in the neonate: A narrative review.

Chylous ascites (CA), also called chyloperitoneum, is a rare form of ascites in the neonate. It results from the leakage of lymph into the peritoneal cavity. There are congenital and acquired forms of CA. CA may occur during fetal life, and the prognosis will depend on its volume, gestational age at the onset, and the association with other anomalies. Lymphangiectasia is the most common congenital cause, and acquired forms are mainly traumatic and/or post-operative. This review aims to gather the most current information on CA and addresses important aspects regarding etiology, pathophysiology, clinic, diagnostic tools, and treatment.

The application of the DAPSI(W)R(M) framework to the plastic pellets chain.

Single-use plastic, few global engagement and lack of policies contribute to the global challenge about plastic marine litter. This form of contamination can cause injury and death of marine wildlife. Microplastics (>5 mm) represent an important fraction of plastic litter. They include the plastic pellets that are used as raw material within plastic industry that can be unintentionally spilled into the environment during the industrial processes. In an initiative in order to facilitate the understanding and communication of plastic pellets as a social and environmental problem, we applied the Drivers-Activities-Pressures-State changes-Impacts (on Welfare)-Responses (as Measures) (DAPSI[W]R[M]) framework to plastic pellets chain. We also analyzed possible mitigating measures and their actions along the plastic pellets chain. This DAPSI(W)R(M) framework aim to show an overview of the plastic pellets chain and solutions for politicians and decision makers to help solve this socio-environmental problem that needs the engagement of all stakeholders involved.

Dietary nucleotide supplementation as an alternative to in-feed antibiotics in weaned piglets.

Nucleotides are important to cell growth and division and are crucial to the rapid proliferation of such cells as the intestinal mucosa and immune cells. Accordingly, the nucleotide requirements of animals are high during periods of rapid growth and periods of stress like post-weaning period. Thus, nucleotide supplementation may be a possible alternative to in-feed antibiotics as growth promoter in this phase. The study aimed to evaluate dietary nucleotide supplementation as an alternative to in-feed antibiotics on performance and gut health of weaned piglets. Ninety-six 21-day-old piglets, weighing 7.44 ±â€¯0.65 kg, were allocated into 1 of 3 treatments (8 pens per treatment; 4 pigs per pen) in a 14-day trial. Dietary treatments consisted of control: corn-soybean meal-based diet; nucleotides: control +2 g/kg of a nutritional additive with purified nucleotides; and antibiotic: control +0.8 g/kg of antibiotic growth promoter based on colistin and tylosin. Performance variables and fecal score were not affected (P > 0.05) by supplementing nucleotide or antibiotic. Nucleotides treatment had similar effect to antibiotic and superior to control (P < 0.05) on enhancing duodenum villus height, jejunum crypt depth, and reduction of Paneth cellular area. Duodenum and ileum of animals supplemented with nucleotides or antibiotics had higher (P < 0.05) number of proliferating cells than did those of control animals, whereas the jejunum of animals that received antibiotic diets presented more (P < 0.05) proliferating cells than either the nucleotides or control animals. Jejunum of nucleotide-treated piglets showed a greater number of apoptotic cells than those fed antibiotic or control diets (P < 0.05). Nucleotides and antibiotic treatments decreased the B lymphocyte counts in duodenum and ileum (P < 0.05) but increased in the jejunum (P < 0.05), when compared to the control treatment. Relative abundance of mitogen-activated protein kinases-6, haptoglobin, and tumor necrosis factor-α mRNA was not influenced (P > 0.05) by treatments. In the ileal, antibiotic supplementation reduced total bacteria quantification compared to nucleotide supplementation or the control (P < 0.05), whereas nucleotides supplementation increased enterobacteria proliferation compared to the antibiotic or control diets (P < 0.05). However, nucleotides and antibiotic reduced (P < 0.05) colon total bacteria quantification when compared to control. These results suggest that the nucleotides source used to weaned piglets improved gut health by modulating the local immune response and modulating intestinal mucosa development, and, therefore, nucleotides may be an alternative to antibiotics as growth promoters.

Short communication: Effect of sampling time relative to the first daily feeding on interpretation of serum fatty acid and beta-hydroxybutyrate concentrations in dairy cattle.

Serum nonesterified fatty acid (NEFA) and beta-hydroxybutyrate (BHBA) concentrations are used to evaluate energy status in peripartum dairy cows. Blood samples from 37 cows in the week before parturition and 47 cows in the first week after parturition from 3 dairy herds were taken 1h before the first feeding (-1h) as well as 4 and 10h after the first feeding. Nonesterified fatty acid concentrations were measured in samples from cows before calving and BHBA was measured in samples from lactating cows. Mean NEFA concentrations in the prepartum cows were significantly higher at -1h (0.20 mmol/L) than at 4h (0.14 mmol/L), but were not different between 4 and 10h (0.17 mmol/L). Using a cutpoint of NEFA > or = 0.4 mmol/L, 32% of cows had high concentrations at -1h compared with 16% of the same cows at 4 and 10h. There were no differences in mean BHBA between -1h (646 micromol/L) and 4h (596 micromol/L), but mean BHBA was higher at 10h (711 micromol/L) than at -1h. Using a cutpoint of BHBA > or = 1,400 micromol/L, there were no differences in the proportions of high BHBA, which were 9, 11, and 13% of cows at -1, 4, and 10h, respectively. Prandial effects on serum NEFA may affect interpretation of this analyte. In order not to misclassify cows when assessing energy status, samples for NEFA must at least be taken at a consistent time relative to feeding within a given herd. When sampling cows to monitor elements of energy metabolism in the prepartum period, there was twice the probability of detecting animals with NEFA values > or = 0.4 mmol/L if they were sampled 1h before the first feed delivery compared with sampling the same cows 4 or 10h after feeding.

Tn7::In2-8 dispersion in multidrug resistant isolates of Acinetobacter baumannii from Chile.

Acinetobacter baumannii is considered an important pathogen in our hospital environment having a well-known capacity to acquire different mechanisms of antibiotic resistance. Previous studies in our laboratory had exposed the high dispersion of class 2 integrons in this species. In the present study, we analyzed 7 multiresistant intI2 positive A. baumannii isolates, 6 of which were found to harbour the Tn7::In2-8 element. Our results demonstrate the unusually high distribution of Tn7::In2-8 among different A. baumannii clones from Chile, suggesting a particular behavior of these elements at geographical level.