Characterization of the Bipolaris maydis: symptoms and pathogenicity in popcorn genotypes (Zea mays L. ) / Caracterização de Bipolaris maydis: sintomas e patogenicidade em genótipos de milho-pipoca (Zea mays L. )

Southern corn leaf blight (SCLB) is one of the most important corn leaf diseases. Appropriate management strategies and the use of resistant cultivars allow disease control. Therefore, knowing the aspects related to the pathogen and the response of hosts makes it possible to design efficient strategies for selecting genotypes resistant to this disease. In this sense, the objective was to carry out the Bipolaris maydis isolate characterization, evaluating the pathogenicity in different popcorn lines and the symptoms generated in the host after inoculation. The isolate characterization consisted of the macromorphological evaluation of the colonies and the micromorphological evaluation of the conidia in the PDA medium. An experiment was carried out in a greenhouse to evaluate the pathogenicity of the isolate, using 20 inbred lines of popcorn in a randomized block design with four replicates. Inoculation was carried out by spraying leaves, with a suspension containing 1.0 x 104 conidia.ml-1 of the CF/UENF 501 isolate of B. maydis. An incidence assessment and three assessments of disease symptom severity were performed, with seven days intervals between evaluations. The morphological characterization data of the isolate were analyzed using descriptive statistics, and for disease severity, the linear regression model was applied the first-degree model. The variance analysis was performed for the linear and angular coefficients obtained for each treatment. When a difference was found, the Scott-Knott clustering algorithm at 5% significance was applied. The isolate had gray-green colonies, a cottony appearance, and an irregular shape. The lines L353, L354, and L624 show more resistance at the beginning and throughout the evaluations. The high virulence of the CF/UENF 501 isolate made it possible to differentiate the lines in terms of disease intensity and the pattern of symptoms presented.

Mancha-de-Bipolaris é uma das mais importantes doenças foliares do milho. Estratégias de manejo adequadas e o uso de cultivar resistente permitem o controle da doença, mas para tanto, conhecer os aspectos associados ao patógeno e a resposta do hospedeiro é necessário para traçar estratégias eficientes para seleção de genótipos resistentes a essa doença. Neste sentido, objetivou-se realizar a caracterização do isolado de Bipolaris maydis avaliando a patogenicidade em diferentes linhagens de milho-pipoca e os sintomas gerados no hospedeiro a partir da inoculação. A caracterização do isolado consistiu na avaliação macromorfológica das colônias e micromofológica dos conídios em meio nutritivo BDA. Para avaliação da patogenicidade do isolado foi conduzido um experimento em casa de vegetação utilizando 20 linhagens endogâmicas de milho-pipoca, com delineamento em blocos casualizados, com quatro repetições. A inoculação foi realizada por meio de pulverização em folhas, com uma suspensão contendo 1,0 x 104 conídios.ml-1 do isolado CF/UENF 501 de B. maydis. Foi realizada uma avaliação de incidência e três avaliações de severidade dos sintomas da doença, com o intervalo de sete dias para cada avaliação. Os dados da caracterização morfológica do isolado foram analisados por meio da estatística descritiva e para severidade da doença foi aplicado o modelo de regressão linear de primeiro grau. Realizou-se a análise de variância para o coeficiente linear e angular obtido para cada tratamento e quando constatada diferença aplicou-se o agrupamento de médias de Scott-knott a 5% de significância. O isolado apresentou colônias com coloração cinza esverdeado, aspecto algodonoso e forma irregular. As linhagens L353 e L354 e L624 estão entre as linhagens que apresentaram maior resistência no inicio e ao longo das avaliações. A elevada virulência do isolado CF/UENF 501 possibilitou diferenciar as linhagens quanto a intensidade da doença, bem como o padrão dos sintomas apresentados.

Characterization of the Bipolaris maydis: symptoms and pathogenicity in popcorn genotypes (Zea mays L.)

Abstract Southern corn leaf blight (SCLB) is one of the most important corn leaf diseases. Appropriate management strategies and the use of resistant cultivars allow disease control. Therefore, knowing the aspects related to the pathogen and the response of hosts makes it possible to design efficient strategies for selecting genotypes resistant to this disease. In this sense, the objective was to carry out the Bipolaris maydis isolate characterization, evaluating the pathogenicity in different popcorn lines and the symptoms generated in the host after inoculation. The isolate characterization consisted of the macromorphological evaluation of the colonies and the micromorphological evaluation of the conidia in the PDA medium. An experiment was carried out in a greenhouse to evaluate the pathogenicity of the isolate, using 20 inbred lines of popcorn in a randomized block design with four replicates. Inoculation was carried out by spraying leaves, with a suspension containing 1.0 x 104 conidia.ml-1 of the CF/UENF 501 isolate of B. maydis. An incidence assessment and three assessments of disease symptom severity were performed, with seven days intervals between evaluations. The morphological characterization data of the isolate were analyzed using descriptive statistics, and for disease severity, the linear regression model was applied the first-degree model. The variance analysis was performed for the linear and angular coefficients obtained for each treatment. When a difference was found, the Scott-Knott clustering algorithm at 5% significance was applied. The isolate had gray-green colonies, a cottony appearance, and an irregular shape. The lines L353, L354, and L624 show more resistance at the beginning and throughout the evaluations. The high virulence of the CF/UENF 501 isolate made it possible to differentiate the lines in terms of disease intensity and the pattern of symptoms presented.

Resumo Mancha-de-Bipolaris é uma das mais importantes doenças foliares do milho. Estratégias de manejo adequadas e o uso de cultivar resistente permitem o controle da doença, mas para tanto, conhecer os aspectos associados ao patógeno e a resposta do hospedeiro é necessário para traçar estratégias eficientes para seleção de genótipos resistentes a essa doença. Neste sentido, objetivou-se realizar a caracterização do isolado de Bipolaris maydis avaliando a patogenicidade em diferentes linhagens de milho-pipoca e os sintomas gerados no hospedeiro a partir da inoculação. A caracterização do isolado consistiu na avaliação macromorfológica das colônias e micromofológica dos conídios em meio nutritivo BDA. Para avaliação da patogenicidade do isolado foi conduzido um experimento em casa de vegetação utilizando 20 linhagens endogâmicas de milho-pipoca, com delineamento em blocos casualizados, com quatro repetições. A inoculação foi realizada por meio de pulverização em folhas, com uma suspensão contendo 1,0 x 104 conídios.ml-1 do isolado CF/UENF 501 de B. maydis. Foi realizada uma avaliação de incidência e três avaliações de severidade dos sintomas da doença, com o intervalo de sete dias para cada avaliação. Os dados da caracterização morfológica do isolado foram analisados por meio da estatística descritiva e para severidade da doença foi aplicado o modelo de regressão linear de primeiro grau. Realizou-se a análise de variância para o coeficiente linear e angular obtido para cada tratamento e quando constatada diferença aplicou-se o agrupamento de médias de Scott-knott a 5% de significância. O isolado apresentou colônias com coloração cinza esverdeado, aspecto algodonoso e forma irregular. As linhagens L353 e L354 e L624 estão entre as linhagens que apresentaram maior resistência no inicio e ao longo das avaliações. A elevada virulência do isolado CF/UENF 501 possibilitou diferenciar as linhagens quanto a intensidade da doença, bem como o padrão dos sintomas apresentados.

Characterization of the Bipolaris maydis: symptoms and pathogenicity in popcorn genotypes (Zea mays L.).

Southern corn leaf blight (SCLB) is one of the most important corn leaf diseases. Appropriate management strategies and the use of resistant cultivars allow disease control. Therefore, knowing the aspects related to the pathogen and the response of hosts makes it possible to design efficient strategies for selecting genotypes resistant to this disease. In this sense, the objective was to carry out the Bipolaris maydis isolate characterization, evaluating the pathogenicity in different popcorn lines and the symptoms generated in the host after inoculation. The isolate characterization consisted of the macromorphological evaluation of the colonies and the micromorphological evaluation of the conidia in the PDA medium. An experiment was carried out in a greenhouse to evaluate the pathogenicity of the isolate, using 20 inbred lines of popcorn in a randomized block design with four replicates. Inoculation was carried out by spraying leaves, with a suspension containing 1.0 x 104 conidia.ml-1 of the CF/UENF 501 isolate of B. maydis. An incidence assessment and three assessments of disease symptom severity were performed, with seven days intervals between evaluations. The morphological characterization data of the isolate were analyzed using descriptive statistics, and for disease severity, the linear regression model was applied the first-degree model. The variance analysis was performed for the linear and angular coefficients obtained for each treatment. When a difference was found, the Scott-Knott clustering algorithm at 5% significance was applied. The isolate had gray-green colonies, a cottony appearance, and an irregular shape. The lines L353, L354, and L624 show more resistance at the beginning and throughout the evaluations. The high virulence of the CF/UENF 501 isolate made it possible to differentiate the lines in terms of disease intensity and the pattern of symptoms presented.

Preventive oral kefir supplementation protects mice from ovariectomy-induced exacerbated allergic airway inflammation.

Asthma is an inflammatory lung disease that affects more women than men in adulthood. Clinical evidence shows that hormonal fluctuation during the menstrual cycle and menopause are related to increased asthma severity in women. Considering that life expectancy has increased and that most women now undergo menopause, strategies to prevent the worsening of asthma symptoms are particularly important. A recent study from our group showed that re-exposure of ovariectomised allergic mice to antigen (ovalbumin) leads to an exacerbation of lung inflammation that is similar to clinical conditions. However, little is known about the role of probiotics in the prevention of asthma exacerbations during the menstrual cycle or menopause. Thus, our objective was to evaluate the effects of supplementation with kefir, a popular fermented dairy beverage, as a preventive strategy for modulating allergic disease. The results show that the preventive kefir administration decreases the influx of inflammatory cells in the airways and exacerbates the production of mucus and the interleukin 13 cytokine. Additionally, kefir changes macrophage polarisation by decreasing the number of M2 macrophages, as shown by RT-PCR assay. Thus, kefir is a functional food that potentially prevents allergic airway inflammation exacerbations in ovariectomised mice.

Influence of variations in the environmental pH on the solubility and water sorption of a calcium silicate-based root canal sealer.

AIM: To evaluate the influence of pH variation on the solubility and water sorption of a premixed calcium silicate-based root canal sealer (EndoSequence BC Sealer) compared to the gold standard based on epoxy resin (AH Plus Jet) after immersion in distilled water and phosphate-buffered saline (PBS). METHODOLOGY: Solubility and water sorption were evaluated after immersion in distilled water or PBS at several pHs (5, 7 and 12) and the values were calculated as percentages of the original mass after 24 h, 7 and 30 days of immersion. The crystalline structures present in the sealers and surface precipitates were assessed by X-ray diffraction. The Shapiro-Wilk's test revealed that data were normally distributed; thus, statistical analysis was performed using one-way anova and Tukey's tests or independent t-test, assuming a 5% α-error. RESULTS: EndoSequence BC Sealer was associated with significantly greater water sorption and solubility compared to AH Plus Jet in all tested conditions (P < 0.05). The acid environment increased the 24 h solubility of EndoSequence BC Sealer immersed in PBS (P < 0.05) and did not induce significative changes in the water sorption (P > 0.05). Alkaline pH reduced the solubility of EndoSequence BC Sealer and increased that of AH Plus Jet at all experimental times and soaking media (P < 0.05). Alkaline environment also significantly increased the water sorption of AH Plus Jet immersed in PBS (P < 0.05). Immersion in PBS significantly reduced the solubility of EndoSequence BC Sealer and significantly increased that of AH Plus Jet (P < 0.05). Precipitates on the surface of EndoSequence BC Sealer corresponding to hydroxyapatite and calcium carbonate were detected after immersion in PBS at pH 5 and 7 for 30 days. CONCLUSIONS: EndoSequence BC Sealer had significantly greater solubility and water sorption than AH Plus Jet. Although the alkaline pH and soaking media directly influenced the solubility and water sorption of the sealers, the solubility of AH Plus Jet remained within the limits recommended by ISO 6876, whilst the solubility of the EndoSequence BC Sealer did not comply with ISO recommendations in all the conditions tested.

Influence of ultraconservative access cavities on instrumentation efficacy with XP-endo Shaper and Reciproc, filling ability and load capacity of mandibular molars subjected to thermomechanical cycling.

AIM: To evaluate the influence of ultraconservative access cavities (UltraAC) on canal shaping and filling ability and load capacity of mandibular molars after root canal preparation with XP-endo Shaper (XP) or Reciproc (RC), under simulated clinical conditions. Traditional access cavities (TradAC) were used for comparison. METHODOLOGY: Forty extracted mandibular molars were scanned by micro-computed tomographic and, based on similar anatomical features, were divided into four groups (n = 10), according to the type of access cavity and canal instrumentation protocol: TradAC/RC, TradAC/XP, UltraAC/RC and UltraAC/XP. All root canal procedures were performed with the teeth placed in a dental mannequin. Teeth were scanned after root canal instrumentation and filling. Unprepared canal area, dentine removed, accumulated hard tissue debris (AHTD), canal transportation, presence of voids and filling material remnants within the pulp chamber were analysed. After restorative procedures, the teeth were subjected to thermomechanical cycling and to a load capacity test. Statistical analyses were performed using two-way anova test, considering the randomized blocks design (P < 0.05). RESULTS: The percentage of unprepared canal area was significantly lower in TradAC groups when compared to UltraAC groups (P < 0.05), regardless of the instrument used. The UltraAC/XP group had significantly lower percentage of root dentine removed when compared to other groups (P < 0.05). UltraAC/XP and TradAC/XP groups had significantly lower percentages of AHTD than UltraAC/RC and TradAC/RC groups (P < 0.05). Regarding canal transportation, in the MB root canals, the TradAC/XP group had significantly lower values than other groups (P < 0.05). In general, in ML and distal root canals, TradAC/XP and UltraAC/XP groups had significantly lower values of canal transportation when compared to other groups (P < 0.05). Moreover, the UltraAC/RC had the greatest canal transportation values in MB and distal canals. The UltraAC groups had significantly greater percentages of voids and volume of remaining root filling material within the pulp chamber after cleaning procedures than TradAC groups (P < 0.05). There was no difference in the load capacity amongst groups (P < 0.05). CONCLUSION: The UltraAC/XP and UltraAC/RC groups had significantly greater areas of unprepared canal walls, significantly more voids and volume of root filling material remnants within the pulp chamber after canal filling. UltraAC/XP was associated with significantly less root dentine removal and significantly more AHTD whilst TradAC/XP had overall significantly less canal transportation. No differences were observed in the load capacity amongst groups.

Preventive oral supplementation with Bifidobacterium longum 51A alleviates oxazolone-induced allergic contact dermatitis-like skin inflammation in mice.

Allergic contact dermatitis (ACD) is a common allergic skin disease that affects individuals subjected to different antigen exposure conditions and significantly impacts the quality of life of those affected. Numerous studies have demonstrated that probiotics suppress inflammation through immunomodulatory effects. In this study, we aimed to evaluate the effect of the probiotic Bifidobacterium longum 51A as a preventive treatment for ACD using an oxazolone-induced murine model. We demonstrated that B. longum 51A exerted a prophylactic effect on oxazolone-induced ACD-like skin inflammation via reductions in ear and dermal thickness and leucocyte infiltration. The administration of inactivated B. longum 51A did not affect oxazolone-induced ACD-like skin inflammation, suggesting that the bacteria must be alive to be effective. Given that B. longum 51A is an acetate producer, we treated mice with acetate intraperitoneally, which also prevented ear and dermal thickening. Moreover, the tissue levels of the inflammatory cytokines and chemokines interleukin (IL)-10, IL-33, tumour necrosis factor-α, chemokine (C-C motif) ligand 2/monocyte chemoattractant protein-1 and chemokine (C-C motif) ligand 5/RANTES were significantly reduced after probiotic treatment, but only IL-33 and IL-10 were reduced when the mice were treated with acetate. These results show that B. longum 51A exerted a potential prophylactic effect on skin inflammation and that acetate represents one potential mechanism. However, other factors are likely involved since these two treatments do not yield the same results.

The influence of endodontic access cavity design on the efficacy of canal instrumentation, microbial reduction, root canal filling and fracture resistance in mandibular molars.

AIM: To assess the impact of conservative endodontic access cavities (CEC) and truss access cavities (TAC) during root canal treatment performed on mandibular molars in terms of: ability to shape and fill root canals, microbial reduction in canals, and cleaning of the pulp chamber. In addition, the fracture resistance of the teeth after coronal restoration was assessed. Traditional endodontic cavities (TEC) were used as a reference technique for comparison. METHODOLOGY: Thirty extracted intact mandibular molars were scanned in a microcomputed tomography device (micro-CT), matched based on similar anatomical features and assigned to TEC, CEC or TAC groups (n = 10). The specimens were accessed accordingly, and root canals were contaminated with bacterial suspensions of Enterococcus faecalis (21 days). Subsequently, the first microbial sample was collected from root canals (S1). The canals were initially prepared with Reciproc Blue R25 instrument followed by a second instrumentation using Reciproc Blue R40. Eight mL of 0.5% NaOCl were used as an irrigant for each instrument. A final irrigation protocol was performed with 2 mL of 0.5% NaOCl, 2 mL of 17% EDTA and another 2 mL of 0.5% NaOCl. Microbial samples were collected from root canals after R25 (S2), R40 (S3) and final irrigation (S4). The teeth were rescanned after S4. Then, root canals were filled, rescanned, restored and the teeth subjected to fracture resistance tests. The statistical analysis was performed with type I negative binomial and beta 0-1 inflation regression models for microbiological analysis. Instrumentation, filling and resistance to fracture results were subjected to anova and Tukey tests (P < 0.05). RESULTS: S4 revealed no significant variations in microbial reduction amongst the groups (P > 0.05). TEC had a significantly lower percentage of unprepared surface area than CEC (P < 0.05). No differences were found regarding the percentage of dentine removed, transportation, centring ability and filling voids amongst the groups (P > 0.05). The TEC group had a significantly lower volume of remaining root filling material within the pulp chamber than CEC and TAC groups (P < 0.05). There was no difference regarding fracture resistance amongst the groups (P > 0.05). CONCLUSION: Conservative access cavities did not offer any advantage in comparison with the traditional endodontic cavities in any of the parameters considered. Furthermore, conservative methods were associated with larger percentages of unprepared canal surface area and larger volumes of remaining root filling material within the pulp chamber.

Current status on minimal access cavity preparations: a critical analysis and a proposal for a universal nomenclature.

In the last decade, several access cavity designs involveing minimal removal of tooth tissue have been described for gaining entry to pulp chambers during root canal treatment. The premise behind this concept assumes that maximum preservation of as much of the pulp chamber roof as possible during access preparation would maintain the fracture resistance of teeth following root canal treatment. However, the smaller the access cavity, the more difficult it may be to visualize and debride the pulp chamber as well as locate, shape, clean and fill the canals. At the same time, a small access cavity may increase the risk of iatrogenic complications as a result of poor visibility, which may have an impact on treatment outcome. This study aimed to critically analyse the literature on minimal access cavity preparations, propose new nomenclature based on self-explanatory abbreviations and highlight the areas in which more research is required. The search was conducted without restrictions using specifics terms and descriptors in four databases. A complementary screening of the references within the selected studies, as well as a manual search in the highest impact journals in endodontics, namely International Endodontic Journal and Journal of Endodontics, was also performed. The initial search retrieved 1831 publications. The titles and abstracts of these papers were reviewed, and the full text of 94 studies was assessed. Finally, a total of 28 studies were identified as evaluating the influence of minimally invasive access cavity designs on the fracture resistance of teeth and on the different stages of root canal treatment (orifice location, canal shaping, canal cleaning, canal filling and retreatment). Overall, the studies had major methodological drawbacks and reported inadequate and/or inconclusive results on the utility of minimally invasive access preparations. Furthermore, they offered limited scientific evidence to support the use of minimally invasive access cavities to improve the outcome of root canal treatment and retreatment; they also provided little evidence that they preserved the fracture resistance of root filled teeth to a greater extent than traditional access cavity preparations. It was concluded that at present, there is a lack of supporting evidence for the introduction of minimally invasive access cavity preparation into routine clinical practice and/or training of undergraduate and postgraduate students.

The impact of minimally invasive root canal preparation strategies on the ability to shape root canals of mandibular molars.

AIM: To evaluate the use of a reduced taper endodontic instrument system (Bassi Logic™ .03 taper) and expandable heat-treated system (XP-endo Shaper) on the ability to shape canals in mandibular molars, by means of microcomputed tomography (micro-CT) analysis. The Reciproc system was used as the reference for comparison. METHODOLOGY: Twenty-four mandibular molars were scanned in a micro-CT, matched based on similar anatomical features and sorted into three groups (n = 8 per group), according to root canal preparation system: Bassi Logic™ .03, XP-endo Shaper and Reciproc. The teeth were mounted onto a mannequin and the pulp chambers were accessed with traditional access cavities. In Bassi Logic™ .03 and Reciproc groups, mesial canals were prepared with size 25, .03 taper or R25 (size 25, .08v taper) instruments and the distal root canal with size 25, .03 taper and size 40, .03 taper or R25 and R40 (size 40, .06v taper), respectively. In XP-endo Shaper groups, all root canals were prepared with XP-endo Shaper (size 30, .04v taper). After root canal preparation, the teeth were rescanned. The percentage of untouched canal areas and the percentage of removed dentine were evaluated separately for mesial and distal root canals. The data were analysed using one-way anova and Tukey tests (P < 0.05). RESULTS: The Bassi Logic™ .03 group was associated with a greater percentage of untouched canal areas when compared to XP-endo Shaper and Reciproc groups for mesial and distal root canals (P < 0.05), but no differences were found between XP-endo Shaper and Reciproc groups (P > 0.05). No significant difference was observed in the percentage of dentine removed amongst the groups for mesial and distal root canals (P > 0.05). CONCLUSION: The use of a reduced taper system (Bassi Logic™ .03) during root canal preparation resulted in a greater percentage of untouched canal areas when compared to XP-endo Shaper and Reciproc instruments. No differences were observed amongst the systems regarding the percentage of dentine removed.

A laboratory study of the impact of ultraconservative access cavities and minimal root canal tapers on the ability to shape canals in extracted mandibular molars and their fracture resistance.

AIM: To evaluate the influence of ultraconservative endodontic access cavities (UEC) and the use of instruments with various tapers (.03 or .05) and tip diameters (25 or 40) on the ability to shape canals in mandibular molars and their fracture resistance in comparison with traditional endodontic access cavities (TEC). METHODOLOGY: Thirty-two intact extracted mandibular molars were scanned in a micro-computed tomography device, matched based on similar anatomical features and assigned to UEC or TEC groups and to subgroups according to mechanical canal preparation with Bassi Logic™ rotary NiTi instruments with .03 or .05 taper (n = 8 per group). The teeth were mounted onto a mannequin head, and the pulp chambers were accessed and the root canals subjected to instrumentation. In the first stage, size 25 endodontic instruments were used, with .03 or .05 tapers. The teeth were re-scanned. Subsequently, a second canal instrumentation was performed with the size 40 instruments with .03 or .05 tapers and scanned again. The root canals were filled and then the teeth restored before being subjected to fracture resistance tests. The data on untouched canal areas, canal transportation, centring ability, the percentage of removed dentine and maximum load at fracture were analysed. One-way anova and Tukey's tests were performed for inter-group analysis. The paired-samples t-test was performed on the results between size 25 and size 40 apical preparations for each individual specimen (P < 0.05). RESULTS: No significant difference was observed for the percentage of untouched canal area when comparing UEC and TEC groups or between the .03 and .05 tapers with the same instrument tip size (P > 0.05). There was a significantly lower percentage of untouched canal area after instrumentation with size 40 instruments when compared to size 25 (P < 0.05). No significant difference in the percentage of dentine removed was observed between the access cavities or the different tapers (P > 0.05). Size 40 apical preparations removed significantly more dentine than size 25 preparations (P < 0.05). No significant differences were observed in canal transportation, centring ability and fracture resistance in any of the tested groups (P > 0.05). CONCLUSIONS: Ultraconservative endodontic access cavities did not offer any advantages in comparison with traditional endodontic access cavities on the ability to shape canals, nor the fracture resistance of mandibular molars. No differences were observed in shaping ability and fracture resistance between .03 and .05 taper canal preparations. Apical preparation with larger instruments resulted in significantly less untouched canal area in all groups.

Effects of alcohol and nicotine consumption on the development of apical periodontitis in rats: a correlative micro-computed tomographic, histological and immunohistochemical study.

AIM: To evaluate the effects of alcohol and nicotine, when used alone or simultaneously, in the development of apical periodontitis induced in rats, using a correlative analytic approach with micro-CT, histological and immunohistochemical analysis. METHODOLOGY: Twenty-eight male Wistar rats were arranged into four groups: Control, Nicotine, Alcohol and Alcohol + Nicotine. The alcohol groups were exposed to self-administration of a 25% alcohol solution, whilst the other groups drunk only filtered water. The nicotine groups received daily intraperitoneal injections of a solution with 0.19 µL of nicotine per mL, whilst the other groups received saline solution. The pulps of the left mandibular first molars were exposed for 28 days to induce periapical lesions. Throughout the experiment, drug administration was maintained, and the animals had their weight and solid and liquid consumption measured. After euthanasia, the mandibles were removed and the area, volume and major diameter of the periapical lesions were measured using micro-computed tomography images. The samples were submitted to histopathological evaluation and immunohistochemistry for RANKL and PTHrP. Statistical analysis was undertaken with a significance level of 5%. Nonparametric data were analysed using the Kruskal-Wallis test followed by Dunn's test, whilst one-way anova followed by Tukey's test was performed for parametric data. RESULTS: The alcohol groups had lower solid and liquid consumption and gained less weight when compared to the nonalcohol groups (P < 0.05). The Alcohol + Nicotine group had lesions with significantly larger volume and area when compared to the other groups (P < 0.05), whilst the Alcohol or Nicotine groups had significantly larger lesions than the control group (P < 0.05). There was no significant difference in the largest diameter of the lesions amongst groups (P > 0.05). The experimental groups had greater inflammatory response scores than the control group (P < 0.05), and the representative samples had more pronounced immunoreaction against RANKL and PTHrP antibodies. CONCLUSIONS: Alcohol and nicotine consumption exacerbated the inflammatory response and the development of periradicular lesions in rats. The association of both substances enhanced their harmful effects.

Does tobacco smoking predispose to apical periodontitis and endodontic treatment need? A systematic review and meta-analysis.

BACKGROUND: Controversial findings exist in the literature regarding the association between tobacco smoking and development of apical periodontitis or need for root canal treatment, with some studies reporting an increase in the prevalence of these outcomes in smokers, whilst others reporting no association. AIM: To evaluate if there is scientific evidence to support an association between tobacco smoking and a greater prevalence of apical periodontitis and/or root canal treatments. DATA SOURCES: A systematic search was performed using MeSH terms and free terms in the PubMed, Scopus, Virtual Health Library (VHL), Cochrane library and Open Gray databases. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS: Observational studies that evaluated the association between smoking and the development or healing of periapical lesion and/or the prevalence of root canal treatment in humans were included. STUDY APPRAISAL AND SYNTHESIS METHODS: A quality assessment of included studies was performed, and the relevant information and findings were evaluated. A meta-analysis using nine included studies was performed through RevMan software, and the certainty of evidence was evaluated through GRADE. RESULTS: Fifteen studies were included, of which 10 were classified as low risk of bias, 4 were considered as moderate risk of bias and 1 as high risk of bias. Ten studies reported that smoking was associated with a greater prevalence of periapical periodontitis and/or root canal treatment. Five studies reported no association. Nine studies were included in the pooled meta-analysis, comprising two subgroups: apical periodontitis and root canal treatment. From these nine studies, eight studies were included in the apical periodontitis subgroup meta-analysis and demonstrated that this condition was significantly more prevalent in smokers when compared to the nonsmokers (odds ratio = 2.78[CI: 1.60, 4.85], P < 0.001; I2  = 79%; no adjusted odds ratio). Three studies were included in the root canal treatment subgroup meta-analysis and demonstrated an increased prevalence in smokers when compared to the nonsmokers (odds ratio = 2.73 [CI: 1.06, 2.83], P < 0.001; I2  = 72%; no adjusted odds ratio). The pooled meta-analysis demonstrated that smokers had twice the chance of having apical periodontitis and/or root canal treatment when compared to nonsmokers (odds ratio of 2.42 [CI: 1.59, 3.68], P < 0.01; I2  = 85%). The GRADE analysis demonstrated moderate certainty of evidence. LIMITATIONS: Several confounding factors were identified such as misinformation regarding the period of time subjects had smoked, as well as the frequency of smoking and the number of cigarettes consumed. No adjustment in odds ratio data for confounding was performed. CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: This systematic review and meta-analysis indicate that tobacco smokers have an increased prevalence of periapical periodontitis and root canal treatments with moderate certainty of evidence.

Prophylactic Bifidobacterium adolescentis ATTCC 15703 supplementation reduces partially allergic airway disease in Balb/c but not in C57BL/6 mice.

Allergic asthma is a chronic disease mainly characterised by eosinophil inflammation and airway remodelling. Many studies have shown that the gut microbiota of allergic individuals differs from that of non-allergic individuals. Although high levels of bifidobacteria have been associated with healthy persons, Bifidobacterium adolescentis ATCC 15703, a gut bacteria, has been associated with allergic individuals in some clinical studies. The relationship between B. adolescentis ATCC 15703 and asthma or allergies has not been well elucidated, and its effect may be dependent on the host's genetic profile or disease state. To elucidate this question, we evaluated the role of preventive B. adolescentis ATCC 15703 treatment on experimental allergic airway inflammation in two genetically different mouse strains, Balb/c and C57BL/6 (B6). Balb/c mice display a greater predisposition to develop allergic responses than B6 mice. Oral preventive treatment with B. adolescentis ATCC 15703 modulated experimental allergic airway inflammation, specifically in Balb/c mice, which showed decreased levels of eosinophils in the airway. B6 mice did not exhibit any significant alterations in eosinophils but showed an increased influx of total leukocytes and neutrophils into the airway. The mechanism underlying the beneficial effects of these bacteria in experimental allergic mice may involve products of bacteria metabolism, as dead bacteria did not mimic the ability of live B. adolescentis ATCC 15703 to attenuate the influx of eosinophils into the airway. To conclude, preventive oral B. adolescentis ATCC 15703 treatment can attenuate the major characteristic of allergic asthma, eosinophil airway influx, in Balb/c but not B6 mice. These results suggest that oral treatment with this specific live bacterial strain may have therapeutic potential for the treatment of allergic airway disease, although its effect is mouse-strain-dependent.

Endemic species may have complex histories: within-refugium phylogeography of an endangered Iberian vole.

Glacial refugia protected and promoted biodiversity during the Pleistocene, not only at a broader scale, but also for many endemics that contracted and expanded their ranges within refugial areas. Understanding the evolutionary history of refugial endemics is especially important in the case of endangered species to recognize the origins of their genetic structure and thus produce better informed conservation practices. The Iberian Peninsula is an important European glacial refugium, rich in endemics of conservation concern, including small mammals, such as the Cabrera vole (Microtus cabrerae). This near-threatened rodent is characterized by an unusual suite of genetic, life history and ecological traits, being restricted to isolated geographic nuclei in fast-disappearing Mediterranean subhumid herbaceous habitats. To reconstruct the evolutionary history of the Cabrera vole, we studied sequence variation at mitochondrial, autosomal and sex-linked loci, using invasive and noninvasive samples. Despite low overall mitochondrial and nuclear nucleotide diversities, we observed two main well-supported mitochondrial lineages, west and east. Phylogeographic modelling in the context of the Cabrera vole's detailed fossil record supports a demographic scenario of isolation of two populations during the Last Glacial Maximum from a single focus in the southern part of the Iberian Peninsula. In addition, our data suggest subsequent divergence within the east, and secondary contact and introgression of the expanding western population, during the late Holocene. This work emphasizes that refugial endemics may have a phylogeographic history as rich as that of more widespread species, and conservation of such endemics includes the preservation of that genetic legacy.

Vitamin C supplementation has no effect on American bullfrog's immune response.

American bullfrog (Lithobates catesbeianus) is the only species raised in Brazilian commercial frog farms, and the intensive culture of these animals has gained great popularity in Brazil over the past several years. Stress is one of the major obstacles in frog culture. To minimise this problem, the aim of the present study was to investigate the role of added vitamin C in the diet of American bullfrogs as an antistress factor through the assessment of plasma corticosterone, leucocyte levels and macrophage activation in animals raised in confinement. The experimental design was entirely randomised, with six treatments (supplementation of 0, 250, 500, 750, 1000 and 2000 mg of vitamin C/kg of feed) and four replications. The plasma corticosterone level, leucocyte level and macrophage activation were evaluated. It was concluded that vitamin C had no influence on the evaluated parameters due to the possible adaptation of the animals to life in captivity (domestication). The results of this research indicate that farmers should not increase the levels of vitamin C in commercial feeds because this would only enhance production costs.

Tracking viral particles in the intestinal contents of the American bullfrog, Lithobates catesbeianus, by Transmission Electron Microscopy / Pesquisa de partículas virais em conteúdo intestinal de rãs-touro americanas, Lithobates catesbeianus, por meio da microscopia eletrônica de transmissão

Feces are an important viral agent elimination route for infected carrier animals and in aquatic organisms these pathogenic agents can very rapidly propagate due to the habitation environment. The objective of this work is to track viral particles in the intestinal contents of bullfrogs (Lithobates catesbeianus) from five commercial frog farms in the region of Vale do Paraíba, in the State of São Paulo, Brazil, using negative contrast transmission electron microscopy (TEM). The Coronaviridae, Paramyxoviridae, Parvoviridae and Herpesviridae families were observed and photographed in specimens. This work emphasizes the importance of adopting sanitary measures in commercial farms and confirms that observing feces by TEM is an efficient and rapid diagnostic tool for detecting viral agents...

Sabendo-se que as fezes são uma importante via de eliminação de agentes virais pelos animais portadores e que, por estarem na água, os agentes patogênicos podem se propagar mais rapidamente, objetivou-se a pesquisa de vírus em conteúdo intestinal de rãs-touro (Lithobates catesbeianus) de cinco ranários comerciais na região do Vale do Paraíba, no estado de São Paulo, pela técnica de microscopia eletrônica de transmissão. As famílias Coronaviridae, Paramixoviridae, Parvoviridae e Herpesviridae foram observadas e fotografadas. Este trabalho ressalta a importância da adoção de medidas sanitárias nas criações, além da confirmação de que a observação de fezes pela microscopia eletrônica de transmissão é uma eficiente ferramenta de diagnóstico rápido para agentes virais...

Suplemento de 1, 25 dihidroxicolecalciferol e redução de cálcio e fósforo disponível para frangos de corte / Supplement of 1, 25-dihydroxycholecalciferol and reduction of calcium and available phosphorus in broiler chickens

Avaliaram-se o desempenho e o rendimento de carcaça e cortes nobres de frangos de corte machos com suplemento nas rações de 1,25 dihidroxicolecalciferol e redução de cálcio e fósforo disponível. Foi utilizado um delineamento em blocos ao acaso, com seis tratamentos: 0,0; 1,0; 2,0; 3,0; 4,0 e 5,0µg de vitamina D3 ativa/kg de ração, e seis repetições com 17 aves cada. Aos 8 e 42 dias de idade cada unidade experimental foi pesada para avaliação do desempenho. Posteriormente, quatro aves/repetição foram retiradas e abatidas para mensuração do rendimento de carcaça e de cortes nobres. A inclusão da vitamina D3 ativa influenciou positivamente (P<0,05) o ganho de peso e a conversão alimentar com as suplementações de 1,0 e 2,0µg/kg. O consumo de ração não apresentou diferença significativa para os níveis estudados. O rendimento de carcaça e de cortes nobres de frangos de corte machos aos 42 dias não foram influenciados pelo suplemento de 1,25 dihidroxicolecalciferol e redução de cálcio e fósforo disponível nas rações. Recomenda-se o fornecimento suplementar de 1,0 a 2,0µg/kg de vitamina D3 ativa nas rações para frangos de corte machos de 8 a 42 dias de idade.

There were evaluated the performance, the carcass yield and noble cuts yield of broilers with supplement of 1,25-dihydroxycholecalciferol and reduction of calcium and available phosphorus. It was used a randomized block design, with six treatments: 0.0; 1.0; 2.0; 3.0; 4.0 and 5.0µg of active vitamin D3/kg of ration, and six repetitions with 17 birds each. At 8 and 42 days of age each experimental unit was weighted in order to evaluated the performance. Later, four broilers/repetition were removed and slaughtered in order to measure the carcass and noble cuts yield. The inclusion of active vitamin D3 influenced positively (P<0.05) the weight gain and the feed conversion at the supplementations of 1.0 and 2.0µg/kg. The feed intake wasn't significative among the studied levels. The carcass and noble cuts of male broilers at 42 days were not influenced by supplement of 1,25-dihydroxycholecalciferol and reduction of calcium and available phosphorus in rations. It is recommended to provide additional of 1.0 up to 2.0µg/kg of active vitamin D3 in rations for male broilers from 8 to 42 days of age.

Detection of white spot syndrome virus in Brazil using negative staining, immunoelectron microscopy and immunocytochemistry techniques / Detección del virus del síndrome de mancha blanca en el Brasil utilizando inmunomicroscopía e inmunomarcación con partículas de oro coloidal

In this study thirty shrimp samples from commercial marine shrimp (L. vannamei) farms of southern region of Brazil were obtained. Hepatopancreas and shell scrapings fragments collected in these animals were processed by transmission electron microscopy using negative staining (rapid preparation), immunoelectron microscopy and immunocytochemistry (immunolabelling with colloidal gold particles) techniques. On the transmission electron microscopy a great number of white spot virus particles, ovoid or bacilliform-to-ellipsoid, measured 230-290 nm in length and 80-160 nm in diameter with intra-nuclear projections were visualized by the negative staining technique in 27 (90 percent) out of 30 samples examined. Using immunoelectron microscopy technique, the anti-VP 664 serum agllutinated a large number of particles formed by antigen-antibody interaction. In the immunocytochemistry technique, the antigen-antibody reaction was styrongly marked by the particles of colloidal gold over the virus. Notably, this is the first report, to our knowledge, describing use of these microscopy techniques to study Brazilian L. vannamei marine shrimp samples; moreover, this methodology also appears to be a viable complementary tool for diagnosing the presence of the white spot virus within shrimp tissues. Importantly, these are the first photoelectron micrographs of the WSSV in Brazil.

Se obtuvieron para el estudio 30 muestras de camarones marinos comerciales (L. vannamei) de las granjas de la región sur de Brasil. Fueron procesados fragmentos de hepatopáncreas y raspados internos del cefalotórax recogidos en estos animales por microscopía electrónica de transmisión con tinción negativa (preparación rápida), inmunomicroscopía y técnicas de inmunocitoquímica (inmunomarcación con partículas de oro coloidal). En la microscopía electrónica de transmisión de un gran número de partículas de virus de la mancha blanca, ovoide o elipsoidal a baciliformes, medían 230-290 nm de longitud y 80-160 nm de diámetro. En 27 (90 por ciento) de las 30 muestras examinadas intra-nuclear proyecciones se visualizaron mediante la técnica de tinción negativa. Utilizando una técnica de inmunomicroscopía electrónica, el anti-suero VP 664 reunió a un gran número de partículas formadas por la interacción antígeno-anticuerpo. En la técnica de inmunocitoquímica, la reacción antígeno-anticuerpo fue fuertemente reforzada por las partículas de oro coloidal en los virus. En particular, en Brasil este es el primer informe, a nuestro entender, que describe el uso de estas técnicas de microscopía en muestras de camarón marino L. vanamei. Además, esta metodología también parece ser una herramienta complementaria viable para diagnosticar la presencia del virus de la mancha blanca en tejidos de camarón. Es importante destacar que estas son las primeras fotos en microscopia electrónica del WSSV obtenidas en Brasil.