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Postweaning diarrhea (PWD) is a multifactorial disease caused by different aetiological agents, like viruses or bacteria and where the role of the microbiota remains unclear. The aim of this study was to assess differences between healthy and diarrheic weaned pigs concerning the prevalence of pathogens and changes in the intestinal microbiota. Eighteen farms with PWD were selected and 277 fecal samples were collected (152 diarrheic vs 125 healthy). Presence of Rotavirus A (RVA), B (RVB), C (RVC) and Porcine Epidemic Diarrhea Virus (PEDV), virulence factors of Escherichia coli and Clostridioides difficile were analyzed by PCR. Finally, the microbiota composition was also study by 16 S rRNA sequencing on 148 samples (102 diarrheic vs 46 healthy). RVA (53.95 % vs 36 %, p=0.04) and RVB (49.67 % vs 28.8 %, p<0.001) were more frequent in diarrheic animals. Furthermore, RVA viral load was higher in diseased animals. VT2 toxin was significantly associated with diarrhea, whereas other virulence factors were not. Presence of C. difficile and PEDV was almost negligible. Regarding microbiota changes, Fusobacteriota phylum was more frequent in diarrheic samples and Ruminococcaceae family in healthy penmates. During the first week postweaning, Enterobacteriace and Campylobacteria were enriched in animals presenting diarrhea. Furthermore, Lactobacillus was detected in those individuals with no RVA infection. In conclusion, RVA seems to play a primary role in PWD. Classic E. coli virulence factors were not associated with diarrhea, indicating the need for revising their implication in disease. Moreover, Lactobacillus was found frequently in animals negative for RVA, suggesting some protective effect. • Rotavirus A (RVA) was the main pathogen implicated in postweaning diarrhea. • Classical Escherichia coli virulence factors were not linked to diarrhea, indicating the need to update this information. • Ruminococcaceae was more abundant in healthy animals, while Fusobacteriota was more frequent in those with diarrhea. • Lactobacillus was associated with lower prevalence of RVA, indicating a possible protective action. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, we analyzed endocrine and nutritional regulation of fatty acid (FA) transporters mRNA expression fatty acid transport protein (FATP1) and fatty acid translocase (CD36) in rainbow trout in vivo and in adipocytes and myocytes in vitro. The expression of FATP1 increased with adipocyte and that of CD36 with myocyte in vitro differentiation suggesting a different role for each transporter during the two cell differentiation programs. Food deprivation (15, 25 and 35days) increased FATP1 and CD36 mRNA expression in white muscle, red muscle and adipose tissue while insulin administration decreased the FATP1 expression in adipose tissue in vivo (21.6pmol/g body mass) and in vitro (1μM) in adipocytes. In trout myotubes insulin (1μM) decreased FATP1 and increased CD36 mRNA expression. Thus, regulation of FA transporters expression by insulin is complex and directed to specific tissue needs. Although FATP1 and CD36 mRNA levels are controlled by insulin, it appears that FATP1 respond more clearly to situations of hyper and hypo-insulinemia in trout muscle and adipose tissue than CD36. FATP1 and CD36 transcription was also modulated by growth hormone in cultured myotubes and isolated adipocytes. Lipopolysaccharide administration (E. coli, serotype O26:B6, 6μg/g body mass) decreased FATP1 mRNA expression in red muscle, adipose tissue and liver after 24h according to changes in lipid metabolism during infection. Tumor necrosis factor (TNFα) (100ng/ml) reduced FATP1 expression in isolated adipocytes. Further, insulin (1μM) and IGF-I (100nM) increased the FA uptake in rainbow trout myotubes through the PI3K/Akt signaling pathway. Overall, we demonstrated not only that feeding condition regulates FATP1 and CD36 mRNA expression in a tissue-specific manner, but also that insulin is an important regulator of these genes in vivo and in vitro and also it stimulates FA uptake in trout muscle cells. [Copyright &y& Elsevier]

Abstract: In the present study, we describe an initial approach to investigate the role of LXR in fish adipose tissue. Rainbow trout (Oncorhynchus mykiss) isolated adipocytes were incubated with LXR agonists, unsaturated fatty acids, tumour necrosis factor-α (TNFα), insulin or growth hormone (GH) for 6h and LXR expression was analyzed. Lipolysis was measured after incubation with one of the LXR agonists and LXR expression was compared with levels of lipolysis. LXR expression was also analyzed during the differentiation of adipocytes in culture. The incubations with agonists in isolated adipocytes indicated that ATP-binding cassette transporter A1 (ABCA1) is an LXR target gene, but lipoprotein lipase (LPL), fatty acid synthase (FAS), hormone-sensitive lipase (HSL) and peroxisome proliferator-activated receptor (PPARs) are not. LXR agonists also induced LXR expression and raised lipolysis levels. Besides, LXR expression was upregulated in parallel with basal lipolysis. LXR mRNA expression was regulated by unsaturated fatty acids, insulin, TNFα and GH in isolated adipocytes. Besides, LXR showed an upregulation during adipocyte differentiation. All these data indicate that LXR is involved in orchestrating the transcriptional regulatory network in trout adipocyte lipid metabolism, specifically, in cholesterol transport, adipocyte differentiation and lipolysis. [Copyright &y& Elsevier]

Abstract: The liver X receptor (LXR) has recently been described in salmonids. In mammals, this receptor is already known as a transcriptional factor that regulates diverse aspects of cholesterol, fatty acid and carbohydrate metabolism in various tissues, including muscle. Here we examined LXR in trout myocytes. For this purpose, we analyzed LXR target gene expression and gene profile during myocyte development. In addition, we studied the transcriptional regulation of LXR by hormones, a pro-inflammatory mediator and unsaturated fatty acids. Trout myocytes were incubated with LXR agonists (T091317, 22(R)-hydroxycholesterol) and unsaturated fatty acids for 24h. Furthermore, differentiated myocytes were incubated with insulin and growth hormone (GH) for 3h, 6h and 18h, and with tumor necrosis factor-α (TNFα) for 24h. Samples were also obtained in various stages of cell differentiation. Our results demonstrate that lipoprotein lipase (LPL), fatty acid synthase (FAS), ATP-binding cassette transporter A1 (ABCA1), peroxisome proliferator-activated receptor-α and β (PPARα, β) are target genes of LXR in trout muscle. LXR agonists increased LXR expression, thereby indicating that this receptor is autoregulated. Unsaturated fatty acids downregulated LXR gene expression. This observation suggests a regulatory mechanism of these molecules on LXR-mediated fatty acid synthesis and uptake. TNFα did not modulate LXR gene transcription. Expression of the LXR gene was activated by insulin and GH. These results suggest that LXR may play a lipogenic role through insulin stimulation and a tendency to promote anabolic effects through GH on trout myocytes. [Copyright &y& Elsevier]

Abstract: The effects of fish oil (FO) substitution by 66% vegetable oils in a diet with already 75% vegetable protein (66VO) on adipose tissue lipid metabolism of gilthead sea bream were analysed after a 14-month feeding trial. In the last 3months of the experiment, a FO diet was administrated to a 66VO group (group 66VO/FO) as a finishing diet. Hormone-sensitive lipase (HSL) activity was measured in adipose tissue and adipocyte size, and HSL, lipoprotein lipase and liver X receptor gene expression in isolated adipocytes, on which lipolysis and glucose uptake experiments were also performed. Lipolysis was measured after incubation with tumour necrosis factor-α (TNFα), linoleic acid, and two conjugated linoleic acid isomers. Glucose uptake was analysed after TNFα or insulin administration. Our results show that FO replacement increased lipolytic activity and adipocyte cell size. The higher proportion of large cells observed in the 66VO group could be involved in their observed lower response to fatty acid treatments and lower insulin sensitivity. The 66VO/FO group showed a moderate return to the FO conditions. Therefore, FO replacement can affect the morphology and metabolism of gilthead sea bream adipocytes which could potentially affect other organs such as the liver. [Copyright &y& Elsevier]

Background and Aims: The World Health Organization (WHO) has reported, as of September 2009, that the influenza A (H1N1) influenza pandemic has originated >300,000 laboratory-confirmed cases and 3917 deaths in 191 countries. It is recognized that pandemic vaccines have their greatest impact as a preventive strategy when administered before or near the peak incidence of cases in an outbreak. Therefore, vaccination campaigns should be in place when influenza A (H1N1) 2009 vaccines are available. We undertook this study to provide updated information on clinical evaluation of influenza A (H1N1) vaccines and review recommendations for influenza A (H1N1) vaccination campaigns and public health policy. Methods: The following methods were used: 1) review of registry at ClinicalTrials.gov. 2) search of PubMed Central (PMC) for influenza A (H1N1) vaccine. 3) review of recommendations of WHO, Mexican Health Secretariat (SSA) and Advisory Committee on Immunization Practices (ACIP) on influenza A (H1N1) vaccination campaigns. Results: Until October 1, 2009 there were 11 available influenza A (H1N1) candidate strains provided by WHO Global Influenza Surveillance Network. ClinicalTrials.gov registers 45 phase I and II clinical trials evaluating immunogenicity and safety of influenza A (H1N1) vaccines. Preliminary results support administration of a single dose and use of adjuvants. Main recommendations of WHO, SSA and ACIP include epidemiologic considerations, objectives, definition of target groups and reinforcement of other mitigation measures. Conclusions: The present pandemic of influenza A (H1N1) has shown mild to moderate severity. Vaccination strategies in Mexico will have the objective of decreasing severe outcomes, slowing transmission, protecting groups at increased risk of infection, complications, or death, and preventing overload of health services. Control of the pandemic should include reinforcement of other non-pharmacologic measures of mitigation and, importantly, an adequate strategy of social communication. [Copyright &y& Elsevier]

Purpose: To investigate the dependence of the α/β ratio determined from in vitro survival curves on the dose ranges. Methods: Detailed clonogenic cell survival experiments were used to determine the least squares estimators for the linear quadratic model for different dose ranges. The cell lines used were CHO AA8, a Chinese hamster fibroblast cell line; U-373 MG, a human glioblastoma cell line; and CP3 and DU-145, two human prostate carcinoma cell lines. The α, β, and α/β ratio behaviors, combined with a goodness-of-fit analysis and Monte Carlo simulation of the experiments, were assessed within different dose regions. Results: Including data from the low-dose region has a significant influence on the determination of the α, β, and α/β ratio from in vitro survival curve data. In this region, the values are poorly determined and have significant variability. The mid-dose region is characterized by more precise and stable values and is in agreement with the linear quadratic model. The high-dose region shows relatively small statistical error in the fitted parameters but the goodness-of-fit and Monte Carlo analyses showed poor quality fits. Conclusion: The dependence of the fitted α and β on the dose range has an impact on the α/β ratio determined from the survival data. The low-dose region had a significant influence that could be a result of a strong linear, rather than quadratic, component, hypersensitivity, and adaptive responses. This dose dependence should be interpreted as a caution against using inadequate in vitro cell survival data for α/β ratio determination. [Copyright &y& Elsevier]

Actinobacillus pleuropneumoniae (APP) causes significant economic losses to the swine industry. Antibiotic treatment can be challenging due to its clinical urgency and the turnover of antimicrobial susceptibility results from the diagnostic laboratory. The aim of this study was to evaluate the vertical transmission of APP within integrated systems as a criterion for optimising antimicrobial treatment in the field, using whole genome sequencing (WGS). Additionally, the genetic variability of Spanish APP isolates has been assessed to decipher antimicrobial resistance (AMR) determinants, toxin presence, serotype, and phenotype/genotype concordance of AMR. A total of 169 isolates from clinical cases of porcine pleuropneumonia with known antimicrobial susceptibility profiles were sequenced. Additionally, 48 NCBI assemblies were included to perform a phylogenetic analysis. Phylogenetic analysis revealed high association between phylogenetic clusters, serotypes, and presence of toxins that are associated within vertically integrated systems by its epidemiological link. Concordance between presence of AMR determinants (genotype) vs in-vitro antimicrobial susceptibility pattern (phenotype) was acceptable for amoxicillin, florfenicol, oxytetracycline, and enrofloxacin using epidemiological cut-off values (ECOFFs), but low concordance was observed for doxycycline and trimethoprim-sulfamethoxazole (T/S). On the other hand, using CLSI clinical breakpoints (CBPs), concordance was acceptable for florfenicol and enrofloxacin and not evaluated for doxycycline, oxytetracycline, trimethoprim-sulfamethoxazole (T/S), and amoxicillin because no CBP are available for them. Finally, WGS has demonstrated the clonality between isolates that shared a common origin (grandmother's farm) and resistance phenotype, suggesting vertical transmission of this pathogen and supporting the use of the epidemiological approach as a good criterion to optimise the antimicrobial use. [Display omitted] • WGS is a valuable tool for evaluating the clonal relationships between clinical APP isolates. • WGS has demonstrated the clonality between isolates that shared a common origin and antimicrobial phenotype. • WGS supports the use of the epidemiological approach as a good criterion to optimize antibiotic treatment. • AST is still the gold standard methodology for predicting antimicrobial resistance in APP for all the antimicrobial families. [ABSTRACT FROM AUTHOR]

A longitudinal study was conducted to investigate the presence of multidrug antimicrobial resistance (multi-AR) in Salmonella enterica in pigs reared under conventional preventative medicine programmes in Spain and the possible association of multi-AR with ceftiofur or tulathromycin treatment during the pre-weaning period. Groups of 7-day-old piglets were treated by intramuscular injection with ceftiofur on four farms ( n = 40 piglets per farm) and with tulathromycin on another four farms ( n = 40 piglets per farm). A control group of untreated piglets ( n = 30 per farm) was present on each farm. Faecal swabs were collected for S. enterica culture prior to treatment, at 2, 7 and 180 days post-treatment, and at slaughter. Minimal inhibitory concentrations of 14 antimicrobial agents, pulsed-field gel electrophoresis and detection of resistance genes representing five families of antimicrobial agents were performed. Plasmids carrying cephalosporin resistant (CR) genes were characterised. Sixty-six S. enterica isolates were recovered from five of eight farms. Forty-seven isolates were multi-AR and four contained bla CTX-M genes harboured in conjugative plasmids of the IncI1 family; three of these isolates were recovered before treatment with ceftiofur. The most frequent AR genes detected were tet (A) (51/66, 77%), sul1 (17/66, 26%); tet (B) (15/66, 23%) and qnrB (10/66, 15%). A direct relation between the use of ceftiofur in these conditions and the occurrence of CR S. enterica was not established. However, multi-AR was common, especially for ampicillin, streptomycin, sulphonamides and tetracycline. These antibiotics are used frequently in veterinary medicine in Spain and, therefore, should be used sparingly to minimise the spread of multi-AR. [ABSTRACT FROM AUTHOR]

This study assessed the dynamics of cephalosporin resistant (CR) E. coli populations during the life cycle of pigs treated early in life with ceftiofur or tulathromycin. The study was conducted at eight conventional pig farms; four for each treatment with ceftiofur or tulathromycin. At each farm, 70 7-day-old piglets were divided into two groups: a control group ( n  = 30) and a treatment group ( n  = 40). Faecal samples were collected on day 0 and on days 2, 7 and 180 post-treatment. Sows were also sampled on day 0. CR E. coli were selected on MacConkey agar with ceftriaxone. On five farms, 7-day-old piglets excreted CR E. coli before treatment associated with the presence of CR E. coli in sows. The occurrence of CR E. coli positive animals decreased with increasing piglet age. The remaining three farms tested negative for CR E. coli during the study period. Results demonstrated great variability in the frequency of CR E. coli positive animals between farms, independent of treatment. Treatment with ceftiofur resulted in a transitory increase in the counts of CR E. coli after 48 h. However, other risk factors including the presence of CR E. coli in sows and animal age were more important than antimicrobial treatment. Accordingly, intervention strategies targeting sows would likely have a beneficial effect in reducing the occurrence of antimicrobial resistance in primary pig production. [ABSTRACT FROM AUTHOR]

The hand hygiene practices of food handlers at a university dining facility (UDF) before and after an educational campaign on hand hygiene were evaluated. The study was performed from June to December 2010, and employed an observation period of 4 h per day during the morning, afternoon and evening shifts, resulting in a total observation time of 543 h. A total of 1960 instances requiring hand hygiene were recorded. No instructions were provided to the food handlers during observations, and they had no knowledge of the study. The overall adherence rate was 11% (216/1960), with a rate of 7% (72/1060) before the educational campaign and 16% (144/900) afterwards ( P < 0.001). However, the short duration of the follow-up period in the present study means the long-term effectiveness of the campaign remains uncertain. Rubbing of dorsal fingers, thumbs and fingertips, especially by kitchen assistants, were the most neglected steps of the technique. The average time spent on hand hygiene before and after the campaign, and its standard deviation, were 12.89 ± 7.25 s and 18.69 ± 13.72 s ( P < 0.0001), respectively. The results revealed a low overall rate of adherence to hand hygiene, and a general failure to execute the technique. The educational campaign resulted in a significant increase in adherence to hand hygiene before handling food (8% versus 38%; P < 0.001). However, it did not result in increased adherence to hand hygiene during and after contact with food, suggesting that food handlers are not yet aware of the importance of hand hygiene in food preparation. Although the time spent on hand hygiene after the educational campaign increased significantly, it remained unsatisfactory. The time the food handlers spent on hand hygiene was slightly below the minimum recommended time of 20 s, except for the cook. [ABSTRACT FROM AUTHOR]

: PurposeTo describe an unusual case of idiopathic retinal vasculitis, aneurysms, and neuroretinitis (IRVAN) syndrome with rapid dynamics in the number and appearance of the aneurysms.: DesignObservational case report.: MethodsClinical and angiographic data of the patient were reviewed.: ResultsIn the course of only 6 months, preexisting retinal aneurysms resolved while new ones appeared. Changes were observed in the shape and size of preexisting lesions. The resolution of lesions in eyes previously untreated by laser is reported for the first time.: ConclusionsVascular lesions in IRVAN syndrome may show an unusually rapid turnover. The resolution of aneurysms is a part of the natural course of the disease and may occur without previous retinal laser photocoagulation. [Copyright &y& Elsevier]