Seed priming with light quality and Cyperus rotundus L. extract modulate the germination and initial growth of Moringa oleifera Lam. seedlings.

Improving plant germination is essential to guarantee better quality seedlings. Thus, this research aimed to evaluate whether the seed priming with light quality (LIQ) and the aqueous extract of Cyperus rotundus (AEC) tuber could modulate the germination and initial growth of Moringa oleifera L. seedlings. The experimental design was a completely randomized in the 4x4 factorial scheme, composed of four LIQ conditions (white, blue, red, and distant red light) and four AEC concentrations (0, 25, 50 and 100%). Seed priming with red light reduced the average emergence time, while blue, red, and extreme red lights associated with 50% of aqueous extract of C. rotundus increased shoot initial length and photosynthetic pigment accumulation. Seed priming with blue light resulted in seedlings with a shorter final shoot length. However, application of 100% of aqueous extract of C. rotundus reversed this. The white light in combination with concentrations of 50 and 100% of AEC promoted a higher relative shoot growth rate of seedlings. The research revealed that seed priming with light quality and aqueous extracts of C. rotundus tubers modulates the germination and initial growth of M. oleifera seedlings. More work needs to be done to determine the responsible compounds in AEC that is responsible for priming growth as phytohormones.

Antimicrobial resistance, biofilm production and invasion of mammary epithelial cells by Enterococcus faecalis and Enterococcus mundtii strains isolated from bovine subclinical mastitis in Brazil.

Members of the genus Enterococcus are among the most relevant etiologic agents of bovine clinical and subclinical mastitis, a major problem for the dairy industry. In Brazil, clonal diversity, and multidrug resistance profiles related to bovine infections need further investigation. In this study, 11 bacterial strains recovered from mastitis subclinical cases detected in different farms of São Paulo, Brazil, were identified as Enterococcus faecalis (n = 8) and Enterococcus mundtii (n = 3) by biochemical testing and MALDI-TOF mass spectrometry. Pulsed-field gel electrophoresis categorized the enterococcal isolates into two main clusters (A and B) with similarity ranging from 85 to 100%. The isolates were shown to be resistant tetracycline (73%), erythromycin (73%), quinupristin-dalphopristin (64%), norfloxacin (9%), fosfomycin (9%) and linezolid (9%). Moreover, seven strains (64%) were considered multidrug-resistant. All the isolates were able to produce biofilms when grown in milk for 24 h: 54·54% were classified as moderate producers and 45·45% were weak producers. Interestingly, only two strains (Ef17 and Em42) remained as moderate biofilm producers after 48 h incubation. Moreover, all isolates showed no ability to form biofilm in tryptic soy broth (TSB) after 24 and 48 h incubation. In addition, cytoskeleton components were partially involved in E. faecalis and E. mundtii entry to epithelial cells as demonstrated by induction of actin stress fibre. In conclusion, enterococci isolates recovered from bovine subclinical mastitis were resistant to several classes of antibiotics, showing the ability to form biofilms in milk and invade mammary epithelial cells, suggesting an advantageous feature in mammary gland colonization during mastitis development. In addition, they can spread along the food chain by different routes and eventually constitute a possible threat for public health, including E. mundtii specie.

A current review of pathogenicity determinants of Streptococcus sp.

The genus Streptococcus comprises important pathogens, many of them are part of the human or animal microbiota. Advances in molecular genetics, taxonomic approaches and phylogenomic studies have led to the establishment of at least 100 species that have a severe impact on human health and are responsible for substantial economic losses to agriculture. The infectivity of the pathogens is linked to cell-surface components and/or secreted virulence factors. Bacteria have evolved sophisticated and multifaceted adaptation strategies to the host environment, including biofilm formation, survival within professional phagocytes, escape the host immune response, amongst others. This review focuses on virulence mechanism and zoonotic potential of Streptococcus species from pyogenic (S. agalactiae, S. pyogenes) and mitis groups (S. pneumoniae).

Single-species (bacterial, fungal, or mycobacterial) biofilms or dual-species (mycobacterial-fungal) biofilms formed in dialysis fluids.

Continuous hemodialysis system monitoring is necessary to prevent microorganism growth and health problems. This study evaluates single- and dual-species biofilm formation in microtiter plates by using dialysis solutions under aerobiosis or 5% CO2 atmosphere. Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, Candida parapsilosis sensu lato, and Mycobacterium smegmatis produce single-species biofilms in all dialysis solutions in both oxygenation conditions. Dual-species biofilm cultures grown at 5% CO2 atmosphere and in dialysate containing glucose reveal that M. smegmatis benefits from its association with C. parapsilosis. The dialysate and its constituent solutions support the growth of all the mono-species and the inter-kingdom mycobacterial/yeast biofilms in both aerobiosis and microaerophilic conditions.

An international multidisciplinary consensus statement on fasting before procedural sedation in adults and children.

The multidisciplinary International Committee for the Advancement of Procedural Sedation presents the first fasting and aspiration prevention recommendations specific to procedural sedation, based on an extensive review of the literature. These were developed using Delphi methodology and assessment of the robustness of the available evidence. The literature evidence is clear that fasting, as currently practiced, often substantially exceeds recommended time thresholds and has known adverse consequences, for example, irritability, dehydration and hypoglycaemia. Fasting does not guarantee an empty stomach, and there is no observed association between aspiration and compliance with common fasting guidelines. The probability of clinically important aspiration during procedural sedation is negligible. In the post-1984 literature there are no published reports of aspiration-associated mortality in children, no reports of death in healthy adults (ASA physical status 1 or 2) and just nine reported deaths in adults of ASA physical status 3 or above. Current concerns about aspiration are out of proportion to the actual risk. Given the lower observed frequency of aspiration and mortality than during general anaesthesia, and the theoretical basis for assuming a lesser risk, fasting strategies in procedural sedation can reasonably be less restrictive. We present a consensus-derived algorithm in which each patient is first risk-stratified during their pre-sedation assessment, using evidence-based factors relating to patient characteristics, comorbidities, the nature of the procedure and the nature of the anticipated sedation technique. Graded fasting precautions for liquids and solids are then recommended for elective procedures based upon this categorisation of negligible, mild or moderate aspiration risk. This consensus statement can serve as a resource to practitioners and policymakers who perform and oversee procedural sedation in patients of all ages, worldwide.

Biofilm formation on different pH conditions by Streptococcus agalactiae isolated from bovine mastitic milk.

Streptococcus agalactiae is among the most relevant aetiologic agent of bovine clinical and subclinical mastitis, a major problem for the dairy industry. In Brazil, clonal diversity, capsular typing and multidrug resistance profiles of S. agalactiae related to human and bovine infections need further investigation. Presently, S. agalactiae isolates of bovine subclinical mastitis, from Brazilian Northeastern region, were submitted to capsular and pulsed-field gel electrophoresis (PFGE)-typing, antimicrobial susceptibility and assays of biofilm formation at different time incubation and pH levels. Sixteen bovine isolates were characterized by polymerase chain reaction assay as S. agalactiae capsular type II (CTII) and classified by PFGE in A1/A2 (n = 06), B1/B2 (n = 06), C (n = 03) and D (n = 01) patterns. Bovine S. agalactiae CTII strains were classified as 25% multidrug-resistant (MDR) with susceptibility to penicillin, linezolid and vancomycin. Biofilm formation on abiotic surface was strain- and time-dependent with significantly higher rates at pH 6·5. In conclusion, S. agalactiae capsular type II isolates recovered from bovine subclinical mastitis produced different pH-dependent biofilm levels. Our findings suggest that biofilm production is modulated by environmental factors and provides S. agalactiae advantageous in colonizing mammary gland during mastitis development, including MDR strains. SIGNIFICANCE AND IMPACT OF THE STUDY: Streptococcus agalactiae is among the most relevant aetiologic agent of bovine clinical and subclinical mastitis, a major problem for the dairy industry. The disease may cause significant economic loss due to decreased production and milk quality and increased use of medicaments. Presently, data demonstrated that biofilm formation favours the establishment of infectious process in health mammary tissue by S. agalactiae and emphasizes that an acidic pH promotes adhesion by biofilm-forming bacterial strains. S. agalactiae strains (25%) showed resistance to tetracycline, azithromycin, erythromycin and clindamycin, and consequently were classified as multidrug-resistant strains.

Inkjet printable-photoactive all inorganic perovskite films with long effective photocarrier lifetimes.

Photoactive perovskite quantum dot films, deposited via an inkjet printer, have been characterized by x-ray diffraction and x-ray photoelectron spectroscopy. The crystal structure and bonding environment are consistent with CsPbBr3 perovskite quantum dots. The current-voltage (I-V) and capacitance-voltage (C-V) transport measurements indicate that the photo-carrier drift lifetime can exceed 1 ms for some printed perovskite films. This far exceeds the dark drift carrier lifetime, which is below 50 ns. The printed films show a photocarrier density 109 greater than the dark carrier density, making these printed films ideal candidates for application in photodetectors. The successful printing of photoactive-perovskite quantum dot films of CsPbBr3, indicates that the rapid prototyping of various perovskite inks and multilayers is realizable.

Antidepressant responsiveness in adulthood is permanently impaired after neonatal destruction of the neurogenic pool.

The dynamic turnover of hippocampal neurons is implicated in the regulation of cognitive and affective behavior. Extending our previous demonstration that administration of dexamethasone (ND) to neonatal rats depletes the resident population of neural precursor cells (NPC) and restrains the size of the neurogenic regions, we now show that the adverse effects of ND persist into adulthood. Specifically, ND impairs repletion of the neurogenic pool and neurogenesis; ND also compromises cognitive performance, the ability to actively adapt to an acute stressor and, the efficacy of glucocorticoid (GC) negative feedback. Interestingly, although ND depletes the neurogenic pool, it does not permanently abolish the proliferative machinery of the residual NPC population; however, ND increases the susceptibility of hippocampal granule neurons to apoptosis. Although the antidepressant fluoxetine (FLX) reverses the latter phenomenon, it does not replenish the NPC pool. Treatment of ND-treated adult rats with FLX also improves GC negative feedback, albeit without rescuing the deleterious effects of ND on behavior. In summary, ND leads to protracted disruption of mental functions, some of which are resistant to antidepressant interventions. We conclude that manipulation of the NPC pool during early life may jeopardize the therapeutic potential of antidepressants in adulthood.

Single Low-Dose Ionizing Radiation Induces Genotoxicity in Adult Zebrafish and its Non-Irradiated Progeny.

This study investigated to what extent a single exposure to low doses of ionizing radiation can induce genotoxic damage in irradiated adult zebrafish (Danio rerio) and its non-irradiated F1 progeny. Four groups of adult zebrafish were irradiated with a single dose of X-rays at 0 (control), 100, 500 and 1000 mGy, respectively, and couples of each group were allowed to reproduce following irradiation. Blood of parental fish and whole-body offspring were analysed by the comet assay for detection of DNA damage. The level of DNA damage in irradiated parental fish increased in a radiation dose-dependent manner at day 1 post-irradiation, but returned to the control level thereafter. The level of DNA damage in the progeny was directly correlated with the parental irradiation dose. Results highlight the genotoxic risk of a single exposure to low-dose ionizing radiation in irradiated individuals and also in its non-irradiated progeny.

The effect of high-fat diet on rat's mood, feeding behavior and response to stress.

An association between obesity and depression has been indicated in studies addressing common physical (metabolic) and psychological (anxiety, low self-esteem) outcomes. Of consideration in both obesity and depression are chronic mild stressors to which individuals are exposed to on a daily basis. However, the response to stress is remarkably variable depending on numerous factors, such as the physical health and the mental state at the time of exposure. Here a chronic mild stress (CMS) protocol was used to assess the effect of high-fat diet (HFD)-induced obesity on response to stress in a rat model. In addition to the development of metabolic complications, such as glucose intolerance, diet-induced obesity caused behavioral alterations. Specifically, animals fed on HFD displayed depressive- and anxious-like behaviors that were only present in the normal diet (ND) group upon exposure to CMS. Of notice, these mood impairments were not further aggravated when the HFD animals were exposed to CMS, which suggest a ceiling effect. Moreover, although there was a sudden drop of food consumption in the first 3 weeks of the CMS protocol in both ND and HFD groups, only the CMS-HFD displayed an overall noticeable decrease in total food intake during the 6 weeks of the CMS protocol. Altogether, the study suggests that HFD impacts on the response to CMS, which should be considered when addressing the consequences of obesity in behavior.

PhenoWorld: a new paradigm to screen rodent behavior.

Modeling depression in animals has inherent complexities that are augmented by intrinsic difficulties to measure the characteristic features of the disorder. Herein, we describe the PhenoWorld (PhW), a new setting in which groups of six rats lived in an ethological enriched environment, and have their feeding, locomotor activity, sleeping and social behavior automatically monitored. A battery of emotional and cognitive tests was used to characterize the behavioral phenotype of animals living in the PhW and in standard conditions (in groups of six and two rats), after exposure to an unpredictable chronic mild stress paradigm (uCMS) and antidepressants. Data reveal that animals living in the PhW displayed similar, but more striking, behavioral differences when exposed to uCMS, such as increased behavioral despair shown in the forced swimming test, resting/sleep behavior disturbances and reduced social interactions. Moreover, several PhW-cage behaviors, such as spontaneous will to go for food or exercise in running wheels, proved to be sensitive indicators of depressive-like behavior. In summary, this new ethological enriched paradigm adds significant discriminative power to screen depressive-like behavior, in particularly rodent's hedonic behavior.

Molecular identification of Lactobacillus spp. associated with puba, a Brazilian fermented cassava food.

Puba or carimã is a Brazilian staple food obtained by spontaneous submerged fermentation of cassava roots. A total of 116 lactobacilli and three cocci isolates from 20 commercial puba samples were recovered on de Man, Rogosa and Sharpe agar (MRS); they were characterized for their antagonistic activity against foodborne pathogens and identified taxonomically by classical and molecular methods. In all samples, lactic acid bacteria were recovered as the dominant microbiota (7.86 ± 0.41 log10 CFU/g). 16S-23S rRNA ARDRA pattern assigned 116 isolates to the Lactobacillus genus, represented by the species Lactobacillus fermentum (59 isolates), Lactobacillus delbrueckii (18 isolates), Lactobacillus casei (9 isolates), Lactobacillus reuteri (6 isolates), Lactobacillus brevis (3 isolates), Lactobacillus gasseri (2 isolates), Lactobacillus nagelii (1 isolate), and Lactobacillus plantarum group (18 isolates). recA gene-multiplex PCR analysis revealed that L. plantarum group isolates belonged to Lactobacillus plantarum (15 isolates) and Lactobacillus paraplantarum (3 isolates). Genomic diversity was investigated by molecular typing with rep (repetitive sequence)-based PCR using the primer ERIC2 (enterobacterial repetitive intergenic consensus). The Lactobacillus isolates exhibited genetic heterogeneity and species-specific fingerprint patterns. All the isolates showed antagonistic activity against the foodborne pathogenic bacteria tested. This antibacterial effect was attributed to acid production, except in the cases of three isolates that apparently produced bacteriocin-like inhibitory substances. This study provides the first insight into the genetic diversity of Lactobacillus spp. of puba.

Molecular identification of Lactobacillus spp. associated with puba, a Brazilian fermented cassava food

Puba or carimã is a Brazilian staple food obtained by spontaneous submerged fermentation of cassava roots. A total of 116 lactobacilli and three cocci isolates from 20 commercial puba samples were recovered on de Man, Rogosa and Sharpe agar (MRS); they were characterized for their antagonistic activity against foodborne pathogens and identified taxonomically by classical and molecular methods. In all samples, lactic acid bacteria were recovered as the dominant microbiota (7.86 ± 0.41 log10 CFU/g). 16S-23S rRNA ARDRA pattern assigned 116 isolates to the Lactobacillus genus, represented by the species Lactobacillus fermentum (59 isolates), Lactobacillus delbrueckii (18 isolates), Lactobacillus casei (9 isolates), Lactobacillus reuteri (6 isolates), Lactobacillus brevis (3 isolates), Lactobacillus gasseri (2 isolates), Lactobacillus nagelii (1 isolate), and Lactobacillus plantarum group (18 isolates). recA gene-multiplex PCR analysis revealed that L. plantarum group isolates belonged to Lactobacillus plantarum (15 isolates) and Lactobacillus paraplantarum (3 isolates). Genomic diversity was investigated by molecular typing with rep (repetitive sequence)-based PCR using the primer ERIC2 (enterobacterial repetitive intergenic consensus). The Lactobacillus isolates exhibited genetic heterogeneity and species-specific fingerprint patterns. All the isolates showed antagonistic activity against the foodborne pathogenic bacteria tested. This antibacterial effect was attributed to acid production, except in the cases of three isolates that apparently produced bacteriocin-like inhibitory substances. This study provides the first insight into the genetic diversity of Lactobacillus spp. of puba.

Characterization of a Chromobacterium haemolyticum population from a natural tropical lake.

AIM: To study genetic diversity of Chromobacterium haemolyticum isolates recovered from a natural tropical lake. METHODS AND RESULTS: A set of 31 isolates were recovered from a bacterial freshwater community by conventional plating methods and subjected to genetic and phenotypic characterization. The 16S ribosomal RNA (rRNA) gene phylogeny revealed that the isolates were related most closely with C. haemolyticum. In addition to the molecular data, our isolates exhibited strong ß-haemolytic activity, were nonviolacein producers and utilized i-inositol, D-mannitol and D-sorbitol in contrast with the other known chromobacteria. Evaluation of the genetic diversity in the 16S rRNA gene, tRNA intergenic spacers (tDNA) and 16S-23S internal transcribed spacers (ITS) unveiled different levels of genetic heterogeneity in the population, which were also observed with repetitive extragenic palindromic (rep)-PCR genomic fingerprinting using the BOX-AR1 primer. tDNA- and ITS-PCR analyses were partially congruent with the 16S rRNA gene phylogeny. The isolates exhibited high resistance to ß-lactamic antibiotics. CONCLUSION: The population genetic heterogeneity was revealed by 16S rRNA gene sequence, ITS and BOX-PCR analysis. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides for the first time an insight into the genetic diversity of phylogenetically close isolates to C. haemolyticum species.

Occurrence of group A rotavirus mixed P genotypes infections in children living in Goiânia-Goiás, Brazil.

Group A rotaviruses (RVA) are the main causing agents of acute gastroenteritis worldwide, having a great impact on childhood mortality in developing countries. The objective of this study was to identify RVA-positive fecal samples with mixed P genotypes by hemi-nested reverse transcriptase-polymerase chain reaction (RT-PCR), followed by sequencing confirmation. Our results showed that, from the 81 RVA-positive samples, 25 were positive for more than one P genotype by hemi-nested RT-PCR. Of these 25 samples, 12 (48%) had their mixed P genotypes confirmed by sequencing and, from these, 10 were identified as P[6]P[8], one as P[4]P[6], and one as P[4]P[6]P[8]. Our results confirm the occurrence of RVA mixed infections among children in Brazil and reinforce the importance of the constant monitoring of RVA circulating strains for the efficacy of control/prevention against these agents.

Molecular characterization of early colonizer bacteria from wastes in a steel plant.

AIMS: Forty-nine bacteria isolated from four newly-produced waste samples of a steel industry, which had a high content of CaO, MgO, Cr and P2O5, were characterized molecularly and phenotypically by susceptibility testing against heavy metals. METHODS AND RESULTS: Phylogenetic analysis using 16S rRNA gene sequences revealed that the isolates belonged to nine genera, Pseudomonas, Micrococcus, Acinetobacter, Bacillus, Dietzia, Kocuria, Diaphorobacter, Staphylococcus and Brevibacillus. Besides, some isolates could be affiliated to species: M. luteus, Ac. junii, Ac. schindleri, B. cereus, K. marina, D. nitroreducens and Staph. warneri. The bacteria that were characterized are taxonomically diverse, and Pseudomonas and Micrococcus predominated. Fingerprinting BOX-PCR revealed high genomic heterogeneity among the isolates. Among the heavy metal compounds Zn, Ni, Pb and Cu were least toxic to the bacterial isolates, whereas Ag inhibited all isolates at 0.001 mmol l(-1). CONCLUSIONS: Heterotrophic bacteria, affiliated with several phylogentic groups, were able to colonize different wastes of a steel industry. SIGNIFICANCE AND IMPACT OF THE STUDY: This study extends our knowledge of the early colonizers bacteria populating siderurgic environments. Some of these bacteria could have potential for recycling siderurgic waste for steel production.

Análise de perigos e pontos críticos de controle na linha de produção de frango inteiro congelado / Hazard analysis and critical control points in production of frozen chicken

A avilcultura brasileira cresceu e sofreu inúmeras mudanças nas duas últimas décadas, devido ao desenvolvimento do mercado interno e aumento das exportações, aliados ao fato de ser a carne de frango um produto saudável e de preço acessível para a população. O Brasil tornou-se o segundo maior produtor mundial de frangos, porém esta carne pode se tornar veículo de transmissão de inúmeros microorganismos, alguns deles patogênicos ao homem, destacando-se Salmonella sp., Campylobacter sp., E. coli enteropatogênica, S. aureus, comumente associados à operacionalização insatisfatória das diversas etapas do processamento das aves. Teve como objetivo elaborar um plano APCC (Análise de Perigos e Pontos Críticos de Controle) para uma linha de produção de frango inteiro congelado, de uma indústria situada no estado do Rio de Janeiro, realizando-se um estudo criterioso de todas as etapas do processamento, desde o recebimento da matéria-prima até a obtenção do produto final, visando a fabricação de produtos seguros para o consumidor e adequação aos requisitos legais, iniciando com uma descrição detalhada das características do produto, principais pontos de venda e elaboração de fluxograma de processamento, analisando a partir destes lados a ocorrência de perigos biológicos, químicos e físicos potenciais para a saúde do consumidor, onde em cada etapa foram avaliadas as medidas preventivas, a severidade que cada perigo representa e o risco da ocorrência destes perigos dentro do abatedouro. Concluindo-se com a determinação de 5 (cinco) pontos críticos de controle (PCC) biológicos, nas etapas de pré-resfriamento da moela, do fígado, coração e nas etapas de pré-resfriamento das carcaças no primeiro e segundo estágio, onde foram estabelecidos para cada PCC (Ponto Crítico de Controle) os limites críticos para temperatura da água, cloração e vazão da mesma, além da temperatura das carcaças, assim como os procedimentos de monitorização também foram descritos, evidenciando-se o que controlar, como, de quanto em qunto tempo deveria ser controlado e o responsável do setor por esta monitorização, estabelecendo ainda as ações corretivas caso os limites fossem ultrapassados e a especificação dos registrados e medidas adequadas para verificação de cada PCC (Ponto Crítico de Controle).

A case of keratoconjunctivitis due to Ewingella americana and a review of unusual organisms causing external eye infections.

We report the isolation of Ewingella americana from the conjunctivae of a 38 year old female physician with keratoconjunctivitis associated with the use of soft contact lens. The patient was treated successfully with topical ciprofloxacin. The source of the infection remains unknown. All contact lens cleaning materials used by the patient were sterile. Since the patient was a physician, and this organism has been recorded as a cause of nosocomial infections, we checked whether cases of Ewingella americana had been reported, but none were identified. We have identified 39 bacterial species, 27 fungi, 4 viruses, 7 protozoa, 4 helminths, and 2 arthropods which rarely have been associated with keratitis or conjunctivitis. Infectious diseases specialists and ophthalmologists must be aware of the many different causes of this illness, including Ewingella americana. This organism is a rare bacterial cause of keratoconjunctivitis not previously reported in Brazil. It should be added to the list of unusual cases of external eye infections.

Suppression of mouse IgE response by immune complexes.

The effect of antibodies alone or complexed to antigen on an IgE response was compared in mice immunized with a low dose of antigen. The results demonstrated that immune complexes (ICs) at equivalence were more efficient than antibodies in promoting a suppression of this response when they were injected simultaneously or before, but not after, the antigen. This effect was dose dependent, antigen specific, and long lasting. Furthermore, only isologous ICs were suppressive. ICs prepared with IgG1 antibodies were more effective than ICs prepared with IgG2. Digestion of the Fc fragment of the antibody eliminated completely the suppressive action of antibodies alone, but not of ICs. These results indicate that, whereas an Fc-dependent mechanism is responsible for the effect of antibodies, an additional mechanism is also operating in suppression induced by ICs.