MC3R links nutritional state to childhood growth and the timing of puberty.

The state of somatic energy stores in metazoans is communicated to the brain, which regulates key aspects of behaviour, growth, nutrient partitioning and development1. The central melanocortin system acts through melanocortin 4 receptor (MC4R) to control appetite, food intake and energy expenditure2. Here we present evidence that MC3R regulates the timing of sexual maturation, the rate of linear growth and the accrual of lean mass, which are all energy-sensitive processes. We found that humans who carry loss-of-function mutations in MC3R, including a rare homozygote individual, have a later onset of puberty. Consistent with previous findings in mice, they also had reduced linear growth, lean mass and circulating levels of IGF1. Mice lacking Mc3r had delayed sexual maturation and an insensitivity of reproductive cycle length to nutritional perturbation. The expression of Mc3r is enriched in hypothalamic neurons that control reproduction and growth, and expression increases during postnatal development in a manner that is consistent with a role in the regulation of sexual maturation. These findings suggest a bifurcating model of nutrient sensing by the central melanocortin pathway with signalling through MC4R controlling the acquisition and retention of calories, whereas signalling through MC3R primarily regulates the disposition of calories into growth, lean mass and the timing of sexual maturation.

Assessment of the impact of conservation measures by modeling soil loss in Minas Gerais, Brazil.

Gullies are significant contributors to soil degradation in several regions of Brazil, including Minas Gerais, where erosion processes have caused soil loss. The characterization of erosion processes is crucial for the application of measures for recovering degraded areas and reducing erosion impacts. This study models soil loss with the use of InVEST software and assesses the impact of three different scenarios, namely (1) implementation of soil conservation practices and replacement of pasture areas for temporary agriculture, (2) reforestation of pasture areas, and (3) preservation of ciliary forests. Soil loss, sediment exportation, retention, and deposition for the present scenario (2019), as well as the three aforementioned hypothetical scenarios, were estimated. In the present scenario, the estimated mean annual soil loss was 2.75 t/ha year, with 1,449.54 t/year sediment exportation, 9,042.13 t/year retention, and 1,449.54 t/year deposition. The model predicted scenario 1 would result in 2.23 t/ha year mean annual soil loss, 1,300.59 t/year sediment exportation, 9,191.08 t/year retention, and 11,755.76 t/year deposition. Scenario 2 showed 1.92 t/ha year mean annual soil loss, 1,046.69 t/year sediment exportation, 9,444.98 t/year retention, and 10,229.77 t/year deposition, whereas the results for scenario 3 were 2.36 t/ha year, 616.65 t/year, 9,862.06 t/year, and 13,206.47 t/year, respectively. Reforestation and preservation of ciliary forests, along with soil conservation practices, were effective measures for reducing soil loss. Such findings are valuable for the management of areas degraded by erosion processes.

A global perspective on bacterial diversity in the terrestrial deep subsurface.

While recent efforts to catalogue Earth's microbial diversity have focused upon surface and marine habitats, 12-20 % of Earth's biomass is suggested to exist in the terrestrial deep subsurface, compared to ~1.8 % in the deep subseafloor. Metagenomic studies of the terrestrial deep subsurface have yielded a trove of divergent and functionally important microbiomes from a range of localities. However, a wider perspective of microbial diversity and its relationship to environmental conditions within the terrestrial deep subsurface is still required. Our meta-analysis reveals that terrestrial deep subsurface microbiota are dominated by Betaproteobacteria, Gammaproteobacteria and Firmicutes, probably as a function of the diverse metabolic strategies of these taxa. Evidence was also found for a common small consortium of prevalent Betaproteobacteria and Gammaproteobacteria operational taxonomic units across the localities. This implies a core terrestrial deep subsurface community, irrespective of aquifer lithology, depth and other variables, that may play an important role in colonizing and sustaining microbial habitats in the deep terrestrial subsurface. An in silico contamination-aware approach to analysing this dataset underscores the importance of downstream methods for assuring that robust conclusions can be reached from deep subsurface-derived sequencing data. Understanding the global panorama of microbial diversity and ecological dynamics in the deep terrestrial subsurface provides a first step towards understanding the role of microbes in global subsurface element and nutrient cycling.

European Association for Endoscopic Surgery (EAES) consensus on Indocyanine Green (ICG) fluorescence-guided surgery.

BACKGROUND: In recent years, the use of Indocyanine Green (ICG) fluorescence-guided surgery during open and laparoscopic procedures has exponentially expanded across various clinical settings. The European Association of Endoscopic Surgery (EAES) initiated a consensus development conference on this topic with the aim of creating evidence-based statements and recommendations for the surgical community. METHODS: An expert panel of surgeons has been selected and invited to participate to this project. Systematic reviews of the PubMed, Embase and Cochrane libraries were performed to identify evidence on potential benefits of ICG fluorescence-guided surgery on clinical practice and patient outcomes. Statements and recommendations were prepared and unanimously agreed by the panel; they were then submitted to all EAES members through a two-rounds online survey and results presented at the EAES annual congress, Barcelona, November 2021. RESULTS: A total of 18,273 abstracts were screened with 117 articles included. 22 statements and 16 recommendations were generated and approved. In some areas, such as the use of ICG fluorescence-guided surgery during laparoscopic cholecystectomy, the perfusion assessment in colorectal surgery and the search for the sentinel lymph nodes in gynaecological malignancies, the large number of evidences in literature has allowed us to strongly recommend the use of ICG for a better anatomical definition and a reduction in post-operative complications. CONCLUSIONS: Overall, from the systematic literature review performed by the experts panel and the survey extended to all EAES members, ICG fluorescence-guided surgery could be considered a safe and effective technology. Future robust clinical research is required to specifically validate multiple organ-specific applications and the potential benefits of this technique on clinical outcomes.

Quantitative analysis of culturable bacteria, levels of endotoxins, inflammatory mediators and substance P in teeth with symptomatic irreversible pulpitis and in teeth with vital normal pulp tissues.

AIM: To comparatively analyse the levels of culturable bacteria, endotoxins (LPS), tumour necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß) and substance P in teeth with symptomatic irreversible pulpitis (SIP) and vital normal pulp (VNP) tissues. METHODOLOGY: Thirty-two patients were included (20 teeth with SIP and 12 teeth with VNP tissues) in this cross-sectional study. Samples were collected from the full length of the root canals (microbial analysis) and periapical tissues (2 mm beyond the apex for immunological analysis), using sterile absorbent paper points. The levels of culturable bacteria (culture method), endotoxins (LAL Pyrogent 5000), TNF-α, IL-1ß and substance P (ELISA) were assessed. The Mann-Whitney test was used for comparisons between the levels of CFU/mL, LPS, TNF-α, IL-1ß and substance P in the SIP and VNP groups. The statistical analysis was performed with the significance level set at 5%. RESULTS: Culturable bacteria were recovered from all teeth with SIP. On the other hand, no positive cultures were observed in the VNP tissues group (p > .05). The levels of LPS were approximately four times higher in teeth with SIP than in teeth with VNP tissues (p < .05). Higher levels of TNF-α and substance P were detected in teeth with SIP (p < .05). On the other hand, no difference in the levels of IL-1ß was detected between the two groups (p > .05). CONCLUSION: Teeth with symptomatic irreversible pulpitis present higher levels of culturable bacteria, endotoxins, TNF-α and substance P than those with vital normal pulp tissues. On the other hand, the levels of IL-1ß were similar in teeth from both groups suggesting reduced implications of this inflammatory mediator in the early stages of infection.

Stafne's bone defect: a systematic review.

BACKGROUND: This systematic review integrated the available data published in the literature on Stafne's bone defect (SBD), considering the clinical, imaging and histopathological results. MATERIAL AND METHODS: An electronic search was undertaken in six databases. Eligibility criteria were: articles in English, Spanish, and Portuguese describing case reports or case series of SBD, reported up to September/2021. Risk of bias was assessed using the Joanna Briggs Institute tool. RESULTS: A total of 98 articles were retrieved, involving 465 individuals with SBD and were included for quantitative analysis. Mean age was 52.78 years (range: 11-89 years), with male predilection (n=374/80.85%). Radiographs were the most frequent imagiological exams (n=298/64.09%), followed by computed tomography (n=98/21.08%). SBD was more prevalent in the posterior mandible (n=361/93.77%) as a hypodense radiolucent lesion (n=250/77.40%). Mean size was 1.58 cm (range: 0.3-.8.0 cm). Two-hundred-and-two lesions (97.37%) were unilocular and 126 (91.97%) were classified as well-defined. Clinical symptoms were reported in 73 cases, while 68 cases (93.15%) were asymptomatic. Only 34 cases (12.32%) were submitted to histopathological examination. Mean follow-up time was 26.42 ±25.39 months. CONCLUSIONS: SBD is more frequent in male patients in the fifth and sixth decade of life. Classic SBD is radiographically characterized as a single, unilocular and well-defined lesion in the posterior region of the jaw with a radiolucent/hypodense appearance.

European guidelines from the EHTG and ESCP for Lynch syndrome: an updated third edition of the Mallorca guidelines based on gene and gender.

BACKGROUND: Lynch syndrome is the most common genetic predisposition for hereditary cancer but remains underdiagnosed. Large prospective observational studies have recently increased understanding of the effectiveness of colonoscopic surveillance and the heterogeneity of cancer risk between genotypes. The need for gene- and gender-specific guidelines has been acknowledged. METHODS: The European Hereditary Tumour Group (EHTG) and European Society of Coloproctology (ESCP) developed a multidisciplinary working group consisting of surgeons, clinical and molecular geneticists, pathologists, epidemiologists, gastroenterologists, and patient representation to conduct a graded evidence review. The previous Mallorca guideline format was used to revise the clinical guidance. Consensus for the guidance statements was acquired by three Delphi voting rounds. RESULTS: Recommendations for clinical and molecular identification of Lynch syndrome, surgical and endoscopic management of Lynch syndrome-associated colorectal cancer, and preventive measures for cancer were produced. The emphasis was on surgical and gastroenterological aspects of the cancer spectrum. Manchester consensus guidelines for gynaecological management were endorsed. Executive and layperson summaries were provided. CONCLUSION: The recommendations from the EHTG and ESCP for identification of patients with Lynch syndrome, colorectal surveillance, surgical management of colorectal cancer, lifestyle and chemoprevention in Lynch syndrome that reached a consensus (at least 80 per cent) are presented.

Water temperature modulates mercury accumulation and oxidative stress status of common goby (Pomatoschistus microps).

Mercury (Hg) is a widespread pollutant across estuarine and coastal areas, raising concern on its potential impact on aquatic organisms. Hg may origin from natural and anthropogenic sources, being persistent and potentially toxic to biota, ultimately representing a serious risk to human health. Hg accumulation and toxicity may also induce reactive oxygen species (ROS) production in marine organisms, responsible for cell and tissue damage. Additionally, the temperature is undoubtedly an important environmental factor to consider regarding accumulation, due to its marked influence on the physiology and ecology of aquatic organisms. This study aimed to investigate the effect of different temperature scenarios (15, 20 and 25 °C) on the Hg accumulation in Pomatoschistus microps (Krøyer, 1838) liver and muscle, as well as on oxidative stress responses and energy metabolism, after short-term exposure to a naturally contaminated sediment with an environmentally relevant [Hg] (1.2 µg g-1). The results showed that Hg accumulation tends to increase along the temperature gradient with higher values of Hg accumulated in liver than in muscle tissue. The action of antioxidant enzymes and stress proteins seems to be effective in combating oxidative stress in the liver. Despite the action of antioxidant defences in the muscle, oxidative damage was observed at the protein level concomitantly with a decrease in aerobic energy production after exposure to Hg at higher temperatures. These findings are ecologically relevant and highlight the importance of further investigation of combined effects of Hg and other stressors, especially in a scenario of a changing climate where events leading to rapid alterations on water parameters are more frequent.

Bacteria and virulence factors in periapical lesions associated with teeth following primary and secondary root canal treatment.

AIM: This cross-sectional study aimed to investigate the microbial profile and to quantify the levels of endotoxins (LPS) and lipoteichoic acid (LTA) present in periapical lesions associated with root filled teeth and those that had received root canal retreatment. It also aimed to investigate the association between microorganisms and their virulence factors with clinical and radiographic features. METHODOLOGY: Patients with periapical lesions in teeth with post-treatment endodontic disease following primary root canal treatment (n = 19) and unsuccessful root canal retreatment (n = 13) were treatment planned for endodontic microsurgery, where the periapical lesions were collected. Clinical and radiographic data were also collected. For microbiological analysis, nested polymerase chain reaction was used to detect 17 bacterial species. Levels of LPS and LTA were determined using limulus amebocyte lysate and enzyme-linked immunosorbent assays, respectively. The Student t-test or Wilcoxon-Mann-Whitney tests were applied to compare the data on LPS and LTA with clinical and radiographic features. The associations between the clinical and radiographic features and the bacterial species were analysed using the Fisher's exact test. A significance level of 5% was adopted. RESULTS: Bacterial DNA, LPS and LTA were detected in all samples. Parvimonas micra was the most commonly detected species in all groups, followed by Enterococcus faecalis, Fusobacterium nucleatum and Porphyromonas endodontalis. The type of endodontic treatment, whether a primary root canal treatment or retreatment, was not associated with the presence of any bacterial species in periapical lesions. The levels of LPS and LTA in periapical lesions of root filled teeth were not significantly different from those that had been retreated. Associations between the levels of LPS and LTA with clinical signs and symptoms were found. No association was found between specific bacteria and clinical features. CONCLUSION: Periapical lesions associated with teeth after primary root canal treatment and retreatment had similar polymicrobial composition. The levels of LPS and LTA in periapical lesions associated with teeth after primary root canal treatment and retreatment were similar, and both were associated with the same symptomatology.

Heating stability, physical and chemical analysis of calcium silicate-based endodontic sealers.

AIM: To evaluate possible modifications in root canal sealers subjected to a variety of heating conditions using vibrational spectroscopy and analysis of physical and chemical properties. METHODOLOGY: EndoSequence BC Sealer HiFlow, Bio-C Sealer, BioRoot RCS and AH Plus were analysed chemically using Raman spectroscopy (25-220 °C) and Fourier-transform infrared spectroscopy (FT-IR) (37-100 °C ). For FT-IR, the materials were tested individually and mixed with root dentine powder. Scanning electron microscopy (SEM) and coupled energy dispersive spectroscopy (EDS) were used to evaluate surface and chemical elements. ISO 6876-2012 and ASTM-C266-07 specifications were followed to evaluate flow, setting time (moist and dry), solubility and radiopacity. Also, pH analysis at 37 and 100 °C was performed. Shapiro-Wilk and Mixed ANOVA (within and between the effects of the subjects), Levene, and a post hoc analyses with Bonferroni correction were performed (P < 0.05). RESULTS: Vibrational spectroscopy revealed peaks of tricalcium silicate, dicalcium silicate and zirconium dioxide. Chemical changes in the Raman spectra during heating were discrete, as the inorganic content predominated the signalling for all root canal sealers. FT-IR analysis exhibited spectral changes in water absorption for EndoSequence BC Sealer HiFlow and Bio-C Sealer, probably related to dehydration. For BioRoot RCS and AH Plus, no significant chemical changes were observed. Bio-C Sealer exhibited a band of polyethylene glycol only after heating to 100 °C, probably related to its thermal decomposition. SEM/EDS analysis corroborated the composition results observed in vibrational spectroscopy for all materials. Heating to 100 °C significantly changed the flowability of all calcium silicate-based sealers with a wide variation in setting times at both temperatures, along with solubility levels above ISO standards. For all tested sealers, radiopacity fulfilled the requirements, and pH exhibited alkaline values. CONCLUSIONS: The tested calcium silicate-based sealers were affected by heating. Calcium silicate-based root canal sealers had high solubility which is a concern for their clinical use. AH Plus was the only root canal sealer that was stable after heating.

Essential oils from Ocimum basilicum cultivars: analysis of their composition and determination of the effect of the major compounds on Haemonchus contortus eggs.

The continuous use of synthetic anthelmintics against gastrointestinal nematodes (GINs) has resulted in the increased resistance, which is why alternative methods are being sought, such as the use of natural products. Plant essential oils (EOs) have been considered as potential products for the control of GINs. However, the chemical composition and, consequently, the biological activity of EOs vary in different plant cultivars. The aim of this study was to evaluate the anthelmintic activity of EOs from cultivars of Ocimum basilicum L. and that of their major constituents against Haemonchus contortus. The EOs from 16 cultivars as well the pure compound linalool, methyl chavicol, citral and eugenol were used in the assessment of the inhibition of H. contortus egg hatch. In addition, the composition of three cultivars was simulated using a combination of the two major compounds from each. The EOs from different cultivars showed mean Inhibition Concentration (IC50) varying from 0.56 to 2.22 mg/mL. The cultivar with the highest egg-hatch inhibition, Napoletano, is constituted mainly of linalool and methyl chavicol. Among the individual compounds tested, citral was the most effective (IC50 0.30 mg/mL). The best combination of compounds was obtained with 11% eugenol plus 64% linalool (IC50 0.44 mg/mL), simulating the Italian Large Leaf (Richters) cultivar. We conclude that different cultivars of O. basilicum show different anthelmintic potential, with cultivars containing linalool and methyl chavicol being the most promising; and that citral or methyl chavicol isolated should also be considered for the development of new anthelmintic formulations.

Dietary intake from complementary feeding is associated with intestinal barrier function and environmental enteropathy in Brazilian children from the MAL-ED cohort study.

A child's diet contains nutrients and other substances that influence intestinal health. The present study aimed to evaluate the relations between complementary feeding, intestinal barrier function and environmental enteropathy (EE) in infants. Data from 233 children were obtained from the Brazilian site of the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project cohort study. Habitual dietary intake from complementary feeding was estimated using seven 24-h dietary recalls, from 9 to 15 months of age. Intestinal barrier function was assessed using the lactulose-mannitol test (L-M), and EE was determined as a composite measure using faecal biomarkers concentrations - α-1-antitrypsin, myeloperoxidase (MPO) and neopterin (NEO) at 15 months of age. The nutrient adequacies explored the associations between dietary intake and the intestinal biomarkers. Children showed adequate nutrient intakes (with the exception of fibre), impaired intestinal barrier function and intestinal inflammation. There was a negative correlation between energy adequacy and L-M (ρ = -0·19, P < 0·05) and between folate adequacy and NEO concentrations (ρ = -0·21, P < 0·01). In addition, there was a positive correlation between thiamine adequacy and MPO concentration (ρ = 0·22, P < 0·01) and between Ca adequacy and NEO concentration (ρ = 0·23; P < 0·01). Multiple linear regression models showed that energy intakes were inversely associated with intestinal barrier function (ß = -0·19, P = 0·02), and fibre intake was inversely associated with the EE scores (ß = -0·20, P = 0·04). Findings suggest that dietary intake from complementary feeding is associated with decreased intestinal barrier function and EE in children.

Gaps at the interface between dentine and self-adhesive resin cement in post-endodontic restorations quantified in 3D by phase contrast-enhanced micro-CT.

AIM: To assess the extent of gaps between root dentine and titanium or fibreglass post restorations following cementation with a self-adhesive resin cement. METHODOLOGY: Fourteen root filled maxillary central incisors restored with prefabricated posts made of Fibreglass (n = 7) or Titanium (n = 7) and cemented with RelyX Unicem 2 were imaged by rapid, high-resolution phase contrast-enhanced micro-CT (PCE-CT) in a synchrotron X-ray imaging facility (ID19, ESRF, 34 KeV, 0.65 µm pixel resolution). Reconstructions were used to measure canal, cement and post perimeters and cross-sectional areas and interfacial gaps at 0.1 mm increments in the root canal space, along the cervical region of the tooth. Remnants of endodontic sealer (AH Plus), when present, were also quantified. Mann-Whitney and 2-way ANOVA tests were used to compare findings within slices and between the two post groups. Pearson correlation coefficients (r) were determined between the interfacial gaps and the other measured parameters. RESULTS: Clearly detectable gaps were found in 45% (±14%) of the interfaces between dentine and cement, along the canal in the cervical area of the tooth beneath the core. The length of interfacial gaps was moderately correlated to the canal cross-sectional area, to the canal perimeter and to the canal area filled by cement (R = 0.52 ~ 0.55, P < 0.001). There was no significant difference between samples with fibreglass or titanium (P > 0.01). Both post types had defect-free interfaces with cement. Endodontic sealer remnants were found on ~10% of the canal walls and were moderately correlated to the presence of gaps. Approximately 30% of the sealer-affected interfaces exhibited no detachment between dentine, sealer and cement. CONCLUSIONS: Self-adhesive cements had interfacial gaps along substantial regions of the root canal surface, which was not correlated with the amount of cement in the canal. PCE-CT proved to be an excellent non-destructive method to study root canal restorations of hydrated samples in 3D.

Influence of access cavity design and use of operating microscope and ultrasonic troughing to detect middle mesial canals in extracted mandibular first molars.

AIM: To evaluate the influence of various endodontic access cavity designs and the use of an operating microscope (OM) with or without ultrasonic troughing to detect middle mesial canals (MMCs) in extracted mandibular first molars. METHODOLOGY: Sixty extracted mandibular first molars were evaluated by cone beam computed tomography (CBCT) in order to detect the presence of MMCs and then divided into two groups (n = 30) with an equal proportion of 1 molar with MMC for each 3 molars. A specific access cavity design was performed for each group, either a conservative access cavity (CAC) or a traditional access cavity (TAC). Root canals were detected in three assessment stages: (i) no magnification, (ii) using an OM and (iii) using an OM together with ultrasonic troughing. Evaluations were performed on a mannequin head in an ergonomic working position. The confidence obtained in the assessment stages was portrayed by sensitivity, specificity and accuracy, calculated by the area under the ROC curve. The difference in the proportion of correct diagnoses in identifying the MMC using either CAC or TAC preparation, at each of the three stages, was checked using Cochran's Q tests. Binomial tests were performed at each stage to investigate whether there was a difference between the types of endodontic access designs to detect MMCs. Significance was set at P < 0.05. RESULTS: Accuracy increased at each assessment stage. At the third stage, both groups provided perfect accuracy (1.00). Cochran's Q tests indicated that the confidence of MMC detection for both TAC and CAC groups (P < 0.05) increased significantly at each stage. Binomial tests demonstrated that there was no significant difference between the TAC and CAC groups, when evaluation was performed without magnification (P > 0.05), with OM (P > 0.05), or with OM associated with ultrasonic troughing (P > 0.05). CONCLUSION: The access cavity design did not significantly affect detection of middle mesial canals in extracted mandibular first molars placed in a mannequin. However, the use of OM increased the accuracy of the MMC identification, especially when associated with ultrasonic troughing.

Mercury bioaccumulation in the long-fin squid Loligo forbesi near the Mid-Atlantic Ridge: Implications to human exposure.

Due to growing commercial interest as a fishing resource and its intermediate position in the marine trophic chains as both prey and predator, cephalopods can play an important role in mercury (Hg) transfer along the marine food webs, since they can bioaccumulate this metal in its tissues. Our study aims to analyze Hg accumulation in Loligo forbesi caught in the Azores Archipelago (Portugal) quantifying Hg in different tissues (mantle and stomach), as well in the squid stomach content, in order to evaluate the efficiency of Hg transfer from prey to predator. Hg data from the tissues was used to estimate the weekly tolerable Hg intake due to squid consumption. Overall data indicate that Hg measured in the stomach tissue (0.1 ± 0.01 µg g-1) was significantly higher than Hg levels found in the mantle (0.04 ± 0.001 µg g-1) and stomach contents (0.01 ± 0.001 µg g-1). BMF (bioaccumulation factor) was >1 for all the samples, indicating a biomagnification process from prey to predator. Hg concentration in the mantle tissue was correlated with mantle size; although females present higher Hg levels than males, the difference was found to be not related to gender but rather to the fact that females had larger bodies. Finally, considering the Hg concentration found in the mantle and the permitted Hg levels, it is advisable to consume up to 1050-1890g of squid per week, according to the regulatory agencies. Thus, our results indicate that, since these doses are respected, consumption of squids from the Azorean waters do not pose a risk to humans.

Efficacy of reciprocating and ultrasonic activation of 6% sodium hypochlorite in the reduction of microbial content and virulence factors in teeth with primary endodontic infection.

AIM: To evaluate in a clinical trial the efficacy of reciprocating and ultrasonic activation of 6% sodium hypochlorite (NaOCl) in the microbial composition and reduction in microbial load as well as in levels of lipopolysaccharide (LPS) and lipoteichoic acid (LTA) in teeth with primary endodontic infections. METHODOLOGY: Samples were collected from 24 root canals with pulp necrosis and periapical lesions, before and after chemo-mechanical canal preparation. The teeth were randomly divided according to the activation protocol as follows: control group without activation (WA, n = 8), reciprocating activation group using Easy Clean tip (EC, n = 8) and ultrasonic activation group using Irrisonic insert (US, n = 8). Microbiological specimens were processed using a culture technique and microbiota composition was analysed using the checkerboard technique. The levels of LPS and LTA were quantified using limulus amebocyte lysate (LAL) and enzyme-linked immunosorbent assay (ELISA), respectively. The Fisher's exact test, Kruskal-Wallis, Dunn's and Wilcoxon's test with a significance level of P < 0.05 were used for statistical analysis. RESULTS: All initial specimens had growth of viable bacteria in fastidious anaerobe agar (FAA), with an average of 105  CFU mL-1 , whereas only one case had such growth after chemo-mechanical canal preparation. LPS and LTA were recovered in 100% of the cases. Chemo-mechanical canal preparation significantly decreased the levels of LPS and LTA (P < 0.05), but no significant differences were found between the groups (P > 0.05). Through the checkerboard technique, bacteria were found in 100% of the initial specimens with concentrations between <105 and 106 . The most frequently identified microorganisms were Prevotella nigrescens and Enterococcus hirae. After chemo-mechanical canal preparation, many species were not detected in any of the three groups tested. A significant reduction occurred in Group US, followed by Groups EC and WA. CONCLUSIONS: Activation of 6% NaOCl reduced the levels of LPS and LTA with no differences between the groups. However, ultrasonic activation was associated with a greater reduction in microbial load within root canals.

Cryopreservation of Bovine Semen Using Extract of Bertholletia excelsa (Brazil Nuts).

BACKGROUND: Semen cryopreservation is essential in animal breeding programs for improving the availability of genetic resources from animals with high breeding value. OBJECTIVE: To evaluate the addition of Brazil nut extract as a replacement for egg yolk in bovine semen cryopreservation. MATERIALS AND METHODS: Semen was collected from five Nelore bulls and cryopreserved with the addition (treatments) of 0, 25, 50, 75, or 100% Brazil nut extract in the cryoprotectant medium. After thawing, spermatic cells were evaluated for morphology, plasma membrane integrity, spermatic kinetics, and in vitro fertilization. The experimental design was in randomized blocks, and the data were submitted to regression analysis. RESULTS: The minor-type and total defects, and plasma membrane integrity were affected (P < 0.05) as a function of egg yolk substitution with Brazil nut extract. There was a significant effect (P < 0.05) of Brazil nut extract addition on the spermatic kinetics and cleavage rate. CONCLUSION: The addition of Brazil nut extract in the cryoprotective medium as a substitute of egg yolk for freezing bovine semen negatively affects sperm quality and fertility.

Effects of diclofenac and salicylic acid exposure on Lemna minor: Is time a factor?

The global occurrence of pharmaceuticals in the aquatic environment has been considered a particularly concerning problem with unknown consequences. Non-steroidal anti-inflammatory drugs (NSAIDs) including diclofenac (DCF) and salicylic acid (SA), are among the most frequently prescribed drugs in the world, being consequently commonly found in the aquatic environment. Prolonged experiments (with duration of exposure that surpass those recommended by already established testing guidelines) are important to obtain ecologically relevant data to address the issue of NSAIDs ecotoxicity, because by being more realistically (namely in terms of levels and durations of exposure), such tests may indicate realistic challenges posed to aquatic organisms. Among the most common test species that are used for assessing environmental quality, plants play a leading role. Lemna species are among the most important plants used for ecotoxicity testing. Therefore, the aim of this study was to evaluate the temporal effect of a prolonged exposure of DCF and SA on Lemna minor. To attain this purpose, L. minor plants were chronically exposed to 0, 4, 20, and 100 µg/L of both pharmaceuticals, and samplings were performed at 6, 10 and 14 days of exposure. The analyzed endpoints were: levels of chlorophyll a, b and total, carotenoids; and enzymatic biomarkers, such as catalase, ascorbate peroxidase and glutathione-S-transferases. Diclofenac was responsible for alterations in all analyzed parameters in different intervals of exposure. Salicylic acid exposure was not capable of causing alterations on pigment contents of L. minor, however, enzymatic biomarkers were altered at all sampling intervals. Thus, it is possible to conclude that both pharmaceuticals can cause damage on the tested macrophyte species, biochemical parameters being more sensitive than physiological ones. Additional prolonged experiments are required to understand the chronic effects of different pharmaceuticals in the aquatic environment, especially in plants.

A kinetic model of T cell autoreactivity in autoimmune diseases.

We construct a mathematical model of kinetic type in order to describe the immune system interactions in the context of autoimmune disease. The interacting populations are self-antigen presenting cells, self-reactive T cells and the set of immunosuppressive cells consisting of regulatory T cells and Natural Killer cells. The main aim of our work is to develop a qualitative analysis of the model equations and investigate the existence of biologically realistic solutions. Having this goal in mind we describe the interactions between cells during an autoimmune reaction based on biological considerations that are given in the literature and we show that the corresponding system of integro-differential equations has finite positive solutions. The asymptotic behaviour of the solution of the system is also studied. We complement our mathematical analysis with numerical simulations that study the sensitivity of the model to parameters related to proliferation of immunosuppressive cells, destruction of self-antigen presenting cells and self-reactive T cells and tolerance of SRTCs to self-antigens.

Leucopis glyphinivora Tanasijtshuk (Diptera: Chamaemyiidae), a new aphidophagous biocontrol agent; development, survival and comparison with Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae).

The silver fly Leucopis glyphinivora Tanasijtshuk (Diptera: Chamaemyiidae) is an aphidophagous predator during its larval stage. Our study describes the life cycle of L. glyphinivora and evaluates its potential as a biocontrol agent. The development, survival and longevity of L. glyphinivora were observed and compared with those of the aphid gall midge Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae). Tests were conducted under laboratory conditions in Petri dishes with the green peach aphid Myzus persicae Sulzer (Hemiptera: Aphididae) on potato leaves. Leucopis glyphinivora has a 42% longer life cycle than A. aphidimyza. Larval development was 27% longer in L. glyphinivora than in A. aphidimyza. Egg hatch rate and pupal emergence rate were similar in both species, but larval survival was 20% lower for L. glyphinivora than for A. aphidimyza. Sex ratio was approximately 50% in both species. A longer development time for L. glyphinivora in the larval stage could be an advantage for biocontrol by providing more time to exert predation pressure against aphids. However, this may be offset by the lower survival rate found in the silver fly larvae.