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.

Fusobacterium nucleatum and Prevotella in women with periodontitis and preterm birth.

BACKGROUND: Studies try to explain the hypothesis that maternal periodontitis may be associated with preterm birth. MATERIAL AND METHODS: This is a case-control study with 120, 40 cases (gestational age <37 weeks) and 80 controls (gestational age ≥37 weeks), that were submitted to the clinical periodontal examination and subgingival biofilm collection. Bacterial DNA of subgingival biofilm was performed and processed by qPCR. RESULTS: Periodontitis was statistically significant in the Case group (35%) when compared to the Control group (11.2%) and Gingival Bleeding Index (GBI), sites with PS ≥ 4mm and sites with CAL ≥ 5mm were statistically higher in the Case group (p < 0.05). The proportions of Pi (p = 0.026) and Fn (p = 0.041) of subgingival biofilm were higher in the Case group. A greater number of sites with PS ≥ 4mm (r = -0.202; p = 0.026) and CAL ≥ 5mm (r = -0.322; p < 0.001) were correlated to lower gestational age. CONCLUSIONS: Periodontitis, preterm delivery, and/or low birth weight may have a possible relationship based on clinical parameters and the ratio of Pi and Fn at periodontal sites.

Source apportionment of air pollution in European urban areas: Lessons from the ClairCity project.

Air pollution has become a major threat to human health in the last decades, with an increase of acute air pollution episodes in many cities worldwide. Source apportionment modelling provides valuable information on the contribution from different emission source sectors and source regions to distinct air pollutants concentrations. In this study, the CAMx model, with its PSAT tool, was applied to quantify the contribution of multiple source areas, categories and pollutant types to ambient air pollution, namely to PM and NO2 concentrations, over six European urban areas: Bristol (United Kingdom), Amsterdam (The Netherlands), Ljubljana (Slovenia), Liguria Region (Italy), Sosnowiec (Poland) and Aveiro Region (Portugal). Results indicate overall higher annual NO2 and PM concentrations located in the urban centres of the case studies. A comparison between the different areas showed that Liguria is the region with highest NO2 annual mean concentrations, while Ljubljana, Liguria Region and Sosnowiec are the case studies with the highest PM annual mean concentrations. The annual average contributions denote a major influence from road transport to NO2 concentrations, with up to 50%, except in Aveiro region, where road transport presents a lower contribution to NO2 concentrations, and the greatest contributor is the industrial combustion and processes sector with 45%. These results indicate a negligible contribution of the transboundary transport to NO2 concentrations, highlighting the relevance of local sources, while for PM concentrations the transboundary transport is the major contributor. The results highlight the relevance of long-range transport of PM across Europe. The transboundary transport reduces its importance during winter, when residential and commercial combustion increases its contribution. In the case of the Aveiro region, the industrial combustion and processes sector also plays an important contribution to PM concentrations.

Assessing the impacts of citizen-led policies on emissions, air quality and health.

Air pollution is a global challenge, and especially urban areas are particularly affected by acute episodes. Traditional approaches used to mitigate air pollution primarily consider the technical aspects of the problem but not the role of citizen behaviour and day-to-day practices. ClairCity, a Horizon 2020 funded project, created an impact assessment framework considering the role of citizen behaviour to create future scenarios, aiming to improve urban environments and the wellbeing and health of its inhabitants. This framework was applied to six pilot cases: Bristol, Amsterdam, Ljubljana, Sosnowiec, Aveiro Region and Liguria Region, considering three-time horizons: 2025, 2035 and 2050. The scenarios approach includes the Business As Usual (BAU) scenario and a Final Unified Policy Scenarios (FUPS) established by citizens, decision-makers, local planners and stakeholders based on data collected through a citizen and stakeholder co-creation process. Therefore, this paper aims to present the ClairCity outcomes, analysing the quantified impacts of selected measures in terms of emissions, air quality, population exposure, and health. Each case study has established a particular set of measures with different levels of ambition, therefore different levels of success were achieved towards the control and mitigation of their specific air pollution problems. The transport sector was the most addressed by the measures showing substantial improvements for NO2, already with the BAU scenarios, and overall, even better results when applying the citizen-led FUPS scenarios. In some cases, due to a lack of ambition for the residential and commercial sector, the results were not sufficient to fulfil the WHO guidelines. Overall, it was found in all cities that the co-created scenarios would lead to environmental improvements in terms of air quality and citizens' health compared to the baseline year of 2015. However, in some cases, the health impacts were lower than air quality due to the implementation of the measures not affecting the most densely populated areas. Benefits from the FUPS comparing to the BAU scenario were found to be highest in Amsterdam and Bristol, with further NO2 and PM10 emission reductions around 10%-16% by 2025 and 19%-28% by 2050, compared to BAU.

Effect of the intra-alveolar administration of dexamethasone on swelling, trismus, and pain after impacted lower third molar extraction: a randomized, double-blind clinical trial.

BACKGROUND: To evaluate the efficacy of intra-alveolar administration of dexamethasone 4 mg in the control of edema, trismus, and pain resulting from the extraction of impacted lower third molars and the drug permeability through the oral mucosa by in silico prediction. MATERIAL AND METHODS: The randomized, double-blind, split-mouth clinical trial included patients who had both impacted lower third molars in equivalent positions. Hemiarches were divided into control side when dexamethasone was administered orally and experimental side when dexamethasone was administered using the intra-alveolar route. Patients were evaluated considering edema, trismus, and pain. The permeability of dexamethasone through the oral mucosa was assessed by in silico prediction. Student's t-test was selected for comparative analysis of edema and trismus, and the chi-square test analyzed the distribution of postoperative pain between the sides. RESULTS: There were no significant differences between the routes of administration in measuring symptoms between the pre and postoperative times (p>0.05). In silico prediction suggested that dexamethasone molecular characteristics facilitate intra-alveolar administration. CONCLUSIONS: Intra-alveolar administration had similar efficacy to oral administration in controlling symptoms of post-surgical inflammation of impacted lower third molars.

Pituitary neuroendocrine tumors and differentiated thyroid cancer: do metabolic and inflammatory risk factors play roles?

PURPOSE: It is postulated that patients with different types of pituitary neuroendocrine tumors (PitNETs) may present a higher incidence of cancer. Factors underlying individuals becoming overweight, such as insulin resistance, hyperleptinemia, and low-grade inflammation, may play a role in the risk of differentiated thyroid carcinoma (DTC) in such patients. This study aimed to investigate the frequency of and obesity-related risk factors associated with DTC in patients with PitNETs. METHODS: This cross-sectional study involved 149 patients with nonacromegalic PitNETs (AG group), 71 patients with acromegaly (ACRO group), and 156 controls (CG group). All participants underwent insulin and blood glucose measurements with the determination of the homeostatic model assessment-insulin resistance (HOMA-IR) index, leptin, and high-sensitivity C-reactive protein (hsCRP), and they also underwent thyroid ultrasound. Clinically significant nodules were biopsied for subsequent cytopathological evaluation, and participants were operated on when indicated. RESULTS: Patients in the AG group had high levels of insulin resistance and significantly higher levels of leptin and hsCRP compared with those of patients in the ACRO group. There were no cases of DTC in the AG group; two findings, one incidental, of DTC occurred in the CG group, and three cases of DTC were present in the ACRO group. Acromegaly was associated with DTC after adjusted analysis. CONCLUSIONS: Our findings in patients with nonacromegalic PitNETs do not indicate a high risk for DTC despite the presence of metabolic and inflammatory risk factors for neoplastic events. In contrast, acromegaly promotes a greater risk of DTC.

Nicotine exposure during lactation causes disruption of hedonic eating behavior and alters dopaminergic system in adult female rats.

Tobacco smoke during gestation is associated with increased consumption of palatable foods by the offspring in humans and rats. Postpartum relapse is observed in lactating women who quit smoking during pregnancy, putting their children at risk of adverse health outcomes caused by secondhand smoke. Nicotine is transferred through milk and alters the dopaminergic reward system of adult male rats, reducing dopamine action in the nucleus accumbens (NAc) and hypothalamic arcuate nucleus. Here, we evaluated the long-term effects of nicotine-only exposure during lactation on eating behavior, anxiety, locomotion, dopaminergic system, hypothalamic leptin signaling and nicotinic receptor in the adult female rat progeny. Two days after birth (PN2), Wistar rat dams were separated into control and nicotine (Nic) groups for implantation of osmotic minipumps that released respectively saline or 6 mg/kg nicotine. Lactating dams were kept with 6 pups. After weaning (PN21; nicotine withdrawal), only the female offspring were studied. Euthanasia occurred at PN180. Nic females showed hyperphagia, preference for a high-sucrose diet, increased anxiety-like behavior, lower tyrosine hydroxylase (TH), lower dopamine transporter and higher dopamine receptor (Drd2) in NAc; lower Drd1 in prefrontal cortex and lower TH in dorsal striatum (DS). These animals showed changes that can explain their hyperphagia, such as: lower leptin signaling pathway (Leprb, pJAK2, pSTAT3) and Chrna7 expression in hypothalamus. Neonatal nicotine exposure affects the brain reward system of the female progeny differently from males, mainly decreasing dopamine production in NAc and DS. Therefore, Nic females are more susceptible to develop food addiction and obesity.

Evaluation of gully development over several years using GIS and fractal analysis: a case study of the Palmital watershed, Minas Gerais (Brazil).

Soil erosion affects agricultural production by reducing the area of rural properties and altering the dynamics of watersheds. Gullies are a complex and irregular type of erosion form that can reach large dimensions, and studying gullies to stabilize erosion processes is a challenge. This study aims to understand their environmental relationships as a basis for future research and to recover land degraded by soil erosion. We combined mapping techniques using geographic information system (GIS) with temporal evolution of land use and fractal dimensions of gullies using FracLac to determine the stability of gullies in a watershed in south Minas Gerais (Brazil). We used R software to apply linear regressions and tested the statistics to verify the compatibility of the model. Environmental characteristics of the watershed contribute to the formation of gullies, but human activities influence the deflagration of these features. The temporal evolution of the land use demonstrated that nearly 50% of the watershed was used as pastures throughout the years, which contributed to soil degradation. The evolution of the fractal dimension showed fluctuations over the years, indicating that the gullies are not stable. The regressions suggest that the vegetation, geology, land use, channel order, and curvature may influence the fractal dimensions of gullies. We concluded that human activity influences the evolution of gullies; the use of techniques such as vegetation measures can contribute to the stabilization of gullies. We also concluded that fractal analysis is an interesting tool for performing environmental evaluations of irregular and complex features, such as gullies.

Evaluation of the effects of extracts of Maytenus imbricata (Celastraceae) on the treatment of inflammatory and metabolic dysfunction induced by high-refined carbohydrate diet.

The Maytenus genus is a member of the Celastraceae family. Numerous medicinal uses were assigned to species of this genus, with the use of roots, bark, and leaves for the treatment of gastric ulcers, as anti-inflammatory, analgesic, antiallergic, antitumor, among others. Several studies have demonstrated that natural products derived from plants have an important role in the prevention and treatment of obesity. Accordingly, we evaluated the effect of Maytenus imbricata extracts in the treatment of obesity induced by diet rich in refined carbohydrate (HC). BALB/c mice were fed chow or HC diet for 8 weeks. At the beginning of the 9th week, the HC group was subdivided into three groups: (i) group of animals that continued to consume only HC diet; (ii) the group of animals fed HC diet supplemented with ethyl acetate extract of M. imbricata roots (HC + EAE); (iii) the group of animals fed HC diet supplemented with extract in hexane/ethyl ether (HC + HEE). The period of extracts supplementation was 4 weeks. It was observed that EAE and EHE when added to the HC diet modulated the metabolic and inflammatory changes, such as: reduced the adipocytes area, improved glucose intolerance, reduced the levels of triglycerides and resistin in serum, and the number of total leukocytes in blood. In the epididymal adipose tissue, the extracts reduced proinflammatory mediators' concentration. According to the results, it was concluded that the species Maytenus imbricata has the potential to be used for the treatment of obesity.

Correction to: Occurrence of anti-Leptospira spp. antibodies in Rhipidomys spp. from a forest fragment of the Brazilian Cerrado.

The original version of this article unfortunately contains an error. Vanessa do Nascimento Ramos was not included in the original article as one of the contributors. The name is now included in the authorgroup.

Detection of the antiviral activity of epicatechin isolated from Salacia crassifolia (Celastraceae) against Mayaro virus based on protein C homology modelling and virtual screening.

Mayaro fever, caused by Mayaro virus (MAYV) is a sub-lethal disease with symptoms that are easily confused with those of dengue fever, except for polyarthralgia, which may culminate in physical incapacitation. Recently, outbreaks of MAYV have been documented in metropolitan areas, and to date, there is no therapy or vaccine available. Moreover, there is no information regarding the three-dimensional structure of the viral proteins of MAYV, which is important in the search for antivirals. In this work, we constructed a three-dimensional model of protein C of MAYV by homology modelling, and this was employed in a manner similar to that of receptors in virtual screening studies to evaluate 590 molecules as prospective antiviral agents. In vitro bioassays were utilized to confirm the potential antiviral activity of the flavonoid epicatechin isolated from Salacia crassifolia (Celastraceae). The virtual screening showed that six flavonoids were promising ligands for protein C. The bioassays showed potent antiviral action of epicatechin, which protected the cells from almost all of the effects of viral infection. An effective concentration (EC50) of 0.247 µmol/mL was observed with a selectivity index (SI) of 7. The cytotoxicity assay showed that epicatechin has low toxicity, with a 50% cytotoxic concentration (CC50) greater than 1.723 µmol/mL. Epicatechin was found to be twice as potent as the reference antiviral ribavirin. Furthermore, a replication kinetics assay showed a strong inhibitory effect of epicatechin on MAYV growth, with a reduction of at least four logs in virus production. Our results indicate that epicatechin is a promising candidate for further testing as an antiviral agent against Mayaro virus and other alphaviruses.

Socio-epidemiological characterisation of blood donors with asymptomatic Leishmania infantum infection from three Brazilian endemic regions and analysis of the transfusional transmission risk of visceral leishmaniasis.

OBJECTIVES: This study assessed the prevalence of visceral leishmaniasis in blood donors from three endemic regions in Brazil and evaluated the risk of transmission by transfusion. BACKGROUND: Despite strong evidence of the transmission of visceral leishmaniasis through blood transfusion, the real risk, an essential condition for taking effective measures to control this serious disease, has not been determined. METHODS: A multicentre study was performed in highly endemic areas. Candidates eligible for their first blood donation underwent a socio-epidemiological interview, and blood samples were collected for enzyme-linked immunosorbent assay (ELISA) analysis, Western blot and polymerase chain reaction (PCR). Patients transfused with red blood cells or random platelet concentrates collected from these donors were also studied. The results were analysed using descriptive statistics and prevalence estimates, with significance defined as p-values <0·05. RESULTS: Of the 608 eligible donors, 37 (6·1%) were positive for visceral leishmaniasis as per ELISA. The socio-epidemiological analysis showed a significantly higher prevalence in non-Caucasians (p = 0·008). Among 296 patients who received blood components from these donors, the pre-transfusion seropositivity was 7·7%, and 13 patients received blood positive for Leishmania infantum. Six patients were followed up for 90 days, of which two (33·3%) had serological conversion at 60 days. CONCLUSIONS: The results confirm the high prevalence of L. infantum seropositivity among donors in the three regions; the seroconversion in a short period of time in two of six patients suggests the possibility of transmission of the infection by transfusion.

Tingenone, a pentacyclic triterpene, induces peripheral antinociception due to cannabinoid receptors activation in mice.

Several works have shown that triterpenes induce peripheral antinociception by activation of cannabinoid receptors and endocannabinoids; besides, several research groups have reported activation of cannabinoid receptors in peripheral antinociception. The aim of this study was to assess the involvement of the cannabinoid system in the antinociceptive effect induced by tingenone against hyperalgesia evoked by prostaglandin E2 (PGE2) at peripheral level. The paw pressure test was used and the hyperalgesia was induced by intraplantar injection of PGE2 (2 µg/paw). All drugs were injected subcutaneously in the hind paws of male Swiss mice. Tingenone (200 µg/paw) administered into the right hind paw induced a local antinociceptive effect, that was antagonized by AM630, a selective antagonist to CB2 cannabinoid receptor. AM251, a selective antagonist to CB1 cannabinoid receptor, did not alter the peripheral antinociceptive effect of tingenone. MAFP, a fatty acid amide hydrolase (FAAH) inhibitor; VDM11, an anandamide reuptake inhibitor; and JZL184, monoacylglycerol lipase (MAGL) inhibitor did not potentiate the peripheral antinociceptive effect of the lower dose of tingenone (50 µg/paw). The results suggest that tingenone induced a peripheral antinociceptive effect via cannabinoid receptor activation. Therefore, this study suggests a pharmacological potential for a new analgesic drug.

Nutritional quality of packaged foods targeted at children in Brazil: which ones should be eligible to bear nutrient claims?

OBJECTIVES: This study aimed to assess the nutritional quality of food products marketed at children, with and without nutrient claims, using two different approaches. METHODS: Analyses were performed based on a data set with food composition and labelling data from every packaged food marketed at children sold in a major Brazilian supermarket (n=535). Foods were classified as 'healthier' and 'less healthy' according to the UK/Ofcom nutrient profile model and to the NOVA classification based on the level of food processing. Pearson's χ2 test was used to compare proportions between models. Agreement was assessed using Cohen's κ-statistic (P<0.05). RESULTS: The NOVA model was stricter than the UK/Ofcom model, classifying more products as 'less healthy' (91.4%) compared with the nutrient profile-based model (75.0%; P<0.001). Agreement between models was 79.4% (k=0.30), because 72.9% (n=390) of products were categorised as 'less healthy' by both models, and 6.5% (n=35) as 'healthier'. Half of the food products marketed at children from the database (270; 50.5%) bore nutrient claims. From these products with nutrient claims, 95.9% (92.8-98.0) were classified as 'less healthy' by the NOVA model, whereas this percentage was 74.1% (68.4-79.2) according to the UK/Ofcom model (P<0.05). CONCLUSIONS: The high number of foods with low nutritional quality being marketed at children via product packaging and nutrient claims should be of concern to policy makers wanting to improve children's diets and to tackle childhood obesity. The implementation of nutritional quality criteria to ensure that foods targeted at children should be eligible to bear nutrient claims on their labels could avoid a situation where claims mask the overall nutritional status of a food.

Implant osseointegration in irradiated bone: an experimental study.

BACKGROUND AND OBJECTIVES: The aim of this study was to evaluate the effect of radiotherapy on the osseointegration of dental implants in the tibia and the action of platelet-rich plasma (PRP) as an adjuvant therapy. MATERIAL AND METHODS: A total of 18 rabbits received two implants in each tibial epiphysis, totalizing 72 implants. The control group (group I) was composed by six rabbits and did not receive radiotherapy. The test groups (II and III) received a single dose of 1727 cGy. Group II was composed by six irradiated animals and group III by six animals that received irradiation and PRP during implant placement. The implant success rate, the bone-implant contact (BIC), and the bone volume were analyzed. RESULTS: There was no osseointegration in four of the implants, three in group II and one in group III. Total BIC was significantly higher in group I, when compared to the other groups. There was a significant difference of osteoid BIC only between irradiated animals (group II, 8.5%; group III, 4.7%; p = 0.001). On the other hand, the mineralized BIC was significantly higher in group I. Furthermore, group II had a lower mineralized BIC than group III (p = 0.002). Bone volume was higher in the control group (41.3%), followed by group III (33.4%) and II (25.1%), with differences between groups I and II (p = 0.001) and groups II and III (p = 0.022). CONCLUSIONS: The present study showed that both the bone volume and BIC were higher in the control group. However, the failure rates of the implants were low in both irradiated groups. The PRP was a positive adjuvant in the osseointegration process.

Morphometric developmental pattern of bovine handmade cloned concepti in late pregnancy.

Cloning procedures often interfere with conceptus growth and life ex utero, in a set of symptoms known as abnormal offspring syndrome (AOS). The aim of the present study was to compare the developmental pattern of in vivo-derived (IVD), IVF-derived and handmade cloning-derived (NT-HMC) Day 225 bovine concepti using established procedures. Pregnancy diagnosis was performed on Day 30 following blastocyst transfer on Day 7. Conceptus morphometry was assessed by ultrasonography on Day 51, and on Day 225 pregnant cows were killed for morphological examination of concepti. Pregnancy outcome was similar between groups, with greater pregnancy losses in the first trimester (70.6%) and smaller fetuses on Day 51 in the NT-HMC group than in the IVD (14.3%) and IVF (20.0%) groups. However, NT-HMC-derived concepti were twofold larger on Day 225 of gestation than controls. A higher frequency (63.5%) of placentomes larger than the largest in the IVD group was observed in the NT-HMC group, which may be relevant to placental function. Conceptus traits in the IVF group were similar to the IVD controls, with only slight changes in placentome types. Morphological changes in cloned concepti likely affected placental function and metabolism, disrupting the placental constraining mechanism on fetal growth in mid- to late pregnancy.

Public health matters: Innovative approaches for engaging medical students.

BACKGROUND: Public health faces the paradox of being increasingly emphasized by the key health and social care regulators and stakeholders, while remaining a largely under-represented discipline in the context of medical curricula. Enhancing medical student engagement in public health teaching is one way to address this concern. METHODS: We discuss four key solutions to the challenges faced by public health educators in medical schools, and present five case studies which demonstrate innovative approaches to engaging medical students in our discipline. RESULTS: Four different approaches have been piloted by members of the Public Health Educators in Medical Schools (PHEMS) network: (i) ensuring social accountability, (ii) demonstrating clinical relevance, (iii) mapping the core curriculum, and (iv) using technology enhanced learning. Preliminary student feedback suggests that these approaches can be used to position public health as an enabler of modern medical practice, and promote a more holistic understanding of medicine by linking patient-centred care to the population level. CONCLUSIONS: The zeitgeist in both academia and the healthcare system supports the teaching of public health within the medical curriculum; there is also consensus at the political and pedagogical level. The challenge of ensuring engagement now needs to be met at the student-teacher interface.

Microbial analysis of root canal and periradicular lesion associated to teeth with endodontic failure.

The quantification of ten microorganisms at the root ends and in the surrounding periradicular lesions was performed. Thirty 3 mm samples root ends and 30 samples of the surrounding chronic periapical infection were collected during apical microsurgery. Samples were triturated, and the bacterial DNA was obtained. The bacterial quantification was performed by using the SYBR Green system. At least one microorganism was detected in all patients. In both the root end and periapical samples, Fusobacterium nucleatum (71.6%), Dialister pneumosintes (58.3%) and Tannerella forsythia (48.3%) were the most prevalent species. Dialister pneumosintes showed statistically significant values in the root end, and F. nucleatum was also significant in the apical periodontitis samples. A statistically significant association between T. forsythia and Porphyromonas gingivalis in the root ends was observed. Bacterial associations from 2 to 7 species were observed in most samples. Extra-radicular and/or intra-radicular infections were present in all teeth with failed endodontic treatment, and showed polymicrobial infection in most cases, with a predominance of F. nucleatum, D. pneumosintes and T. forsythia. When present, Enterococcus faecalis was never found to be the most prevalent species. The presence of a microbial diversity in post-treatment apical periodontitis confirms the polymicrobial and synergistic characteristic of this process. Our results show that the bacterial array associated with the 3 mm root ends and periradicular lesions in post-treatment apical periodontitis are complex and with a high inter-individual variability. These results might be useful to delineate treatment strategies for microbial elimination in apical periodontitis. Further studies are necessary to elucidate the role of these microorganisms in endodontic treatment failures.

Nitrogen removal in a shallow maturation pond with sludge accumulated during 10 years of operation in Brazil.

Accumulated sludge in polishing (maturation) ponds reduces the hydraulic retention time (smaller useful volume), and this could potentially lead to a decrease in performance. However, settled biomass, present in the sediments, can contribute to nitrogen removal by different mechanisms such as nitrification and denitrification. This study investigated the influence of the bottom sludge present in a shallow maturation pond treating the effluent from an anaerobic reactor on the nitrification and denitrification processes. Nitrification and denitrification rates were determined in sediment cores by applying ammonia pulses. Environmental conditions in the medium were measured and bacteria detected and quantified by real-time polymerase chain reaction (real-time PCR). The pond showed daily cycles of mixing and stratification and most of the bacteria involved in nitrogen removal decreased in concentration from the upper to the lower part of the sludge layer. The results indicate that denitrifiers, nitrifiers and anammox bacteria coexisted in the sludge, and thus different metabolic pathways were involved in ammonium removal in the system. Therefore, the sediment contributed to nitrogen removal, even with a decrease in the hydraulic retention time in the pond due to the volume occupied by the sludge.

Occurrence of anti-Leptospira spp. antibodies in Rhipidomys spp. from a forest fragment of the Brazilian Cerrado.

Leptospirosis is a zoonotic disease of world importance, and its transmission depends on the interaction between humans and animals. Given the necessity to investigate potential hosts of Leptospira spp., this study verified the prevalence of different serovars in the species of Rhipidomys spp., a widespread sigmodont rodent in Brazil. The studied population originates from a semi-evergreen forest located in the county of Uberlândia, in the state of Minas Gerais. The microscopic agglutination test (MAT) was performed with 14 serovars. Thirteen out of the 43 wild rodents captured showed a positive agglutination reaction, with a greater prevalence of the serovars Pyrogenes, Copenhageni, and Canicola. This study found a prevalence of 30.3% anti-Leptospira spp. antibodies; all positive animals were reactive to more than one serovar.