Random sequential adsorption with correlated defects : A series expansion approach.

The random sequential adsorption (RSA) problem holds crucial theoretical and practical significance, serving as a pivotal framework for understanding and optimizing particle packing in various scientific and technological applications. Here the problem of the one-dimensional RSA of k-mers onto a substrate with correlated defects controlled by uniform and power-law distributions is theoretically investigated: the coverage fraction is obtained as a function of the density of defects and several scaling laws are examined. The results are compared with extensive Monte Carlo simulations and more traditional methods based on master equations. Emphasis is given in elucidating the scaling behavior of the fluctuations of the coverage fraction. The phenomenon of universality breaking and the issues of conventional Gaussian fluctuations and the Lévy type fluctuations from a simple perspective, relying on the central limit theorem, are also addressed.

Randomized, double-blind, sham-controlled trial to evaluate the efficacy and tolerability of electroconvulsive therapy in patients with clozapine-resistant schizophrenia.

There is no established treatment for patients with clozapine-resistant schizophrenia (CRS). Clozapine augmentation strategies with antipsychotics or others substances are effective in comparison with placebo while and Electroconvulsive therapy (ECT) showed to be effective in comparison with treatment as usual (TAU) but not with placebo (sham-ECT). In the present double- blind randomized controlled trial, we compared 40 outpatients who received 20 sessions of ECT (n = 21) or sham-ECT (n = 19) (age = 37.40 ± 9.62, males = 77.5 %, illness duration = 14.95 ± 8.32 years, mean total Positive and Negative Syndrome Scale (PANSS) = 101.10 ± 24.91) who fulfilled well-defined CRS criteria including baseline clozapine plasma levels ≥350 ng/mL. The primary outcome was the ≥50 % PANSS Total Score reduction; secondary outcomes were the scores of the PANSS subscales, PANSS five-factor dimensions, PANSS-6 and the Calgary Depression Rating Scale (CDRS). Treatment response was analyzed by percentage reduction, Linear Mixed Models and effect sizes. At baseline both groups showed no differences except for years of school education (included as a covariate). At endpoint, only 1/19 of the completers (5.26 %) in the ECT group and 0/17 in the sham-ECT group showed a ≥50 % total PANSS score reduction. Both groups showed no significant differences of the total PANSS score (F = 0.12; p = 0.73), Positive (F = 0.27, p = 0.61), Negative (F = 0.25, p = 0.62), and General Psychopathology scores (F = 0.01, p = 0.94) as well for all PANSS five factors, the PANSS-6 and CDRS. Thus, the present study found no evidence that ECT is better than Sham-ECT in patients with CRS. Future sham-ECT controlled studies with larger sample sizes are warranted to test the efficacy of ECT for patients with CRS.

Physical properties of a generalized model of multilayer adsorption of dimers.

We investigate the transport properties of a complex porous structure with branched fractal architectures formed due to the gradual deposition of dimers in a model of multilayer adsorption. We thoroughly study the interplay between the orientational anisotropy parameter p_{0} of deposited dimers and the formation of porous structures, as well as its impact on the conductivity of the system, through extensive numerical simulations. By systematically varying the value of p_{0}, several critical and off-critical scaling relations characterizing the behavior of the system are examined. The results demonstrate that the degree of orientational anisotropy of dimers plays a significant role in determining the structural and physical characteristics of the system. We find that the Einstein relation relating to the size scaling of the electrical conductance holds true only in the limiting case of p_{0}→1. Monitoring the fractal dimension of the interface of the multilayer formation for various p_{0} values, we reveal that in a wide range of p_{0}>0.2 interface shows the characteristic of a self-avoiding random walk, compared to the limiting case of p_{0}→0 where it is characterized by the fractal dimension of the backbone of ordinary percolation cluster at criticality. Our results thus can provide useful information about the fundamental mechanisms underlying the formation and behavior of wide varieties of amorphous and disordered systems that are of paramount importance both in science and technology as well as in environmental studies.

Exposure to Pfaffia glomerata causes oxidative stress and triggers hepatic changes.

Medicinal plant species are genetically engineered to obtain higher production of biomass and specific secondary metabolites, which can be used in the pharmaceutical industry. The aim of the present study was to evaluate the effect of Pfaffia glomerata (Spreng.) Pedersen tetraploid hydroalcoholic extract on the liver of adult Swiss mice. The extract was prepared from the plant roots and given to the animals by gavage, for 42 days. The experimental groups were treated with water (control), Pfaffia glomerata tetraploid hydroalcoholic extract (100, 200 and 400 mg/kg) and Pfaffia glomerata tetraploid hydroalcoholic extract discontinuously (200 mg/kg). The last group received the extract every 3 days, for 42 days. The oxidative status, mineral dynamics, and cell viability were analysed. The liver weight and the number of viable hepatocytes were reduced, despite the increased cell's number. Increased levels of malondialdehyde and nitric oxide, and changes in iron, copper, zinc, potassium, manganese and sodium levels were observed. aspartate aminotransferase levels were increased while alanine aminotransferase levels were decreased due to BGEt intake. Our results showed that BGEt induced alterations of oxidative stress biomarkers leading to liver injury, which was associated with a reduction in the number of hepatocytes.

Infiltration OF 5Y-PSZ with thermally compatible glass: Strength, microstructure and failure mode analyses.

This study set out to develop a thermally compatible glass to be infiltrated into zirconia partially stabilized by yttrium oxide (5Y-PSZ), to characterize it, and to evaluate its structural reliability and mechanical behavior. 5Y-PSZ zirconia discs (N = 90), dimensions 1.5 mm × 15 mm were produced, polished with #600 alumina oxide and #1200 silicon carbide sandpaper in a polisher. Three groups of 5Y-PSZ discs were assigned (n = 30): Zctrl: as sintered zirconia, Zinf-comp: glass-infiltrated zirconia on the occlusal surface, and sintered, and Zinf-tens: glass-infiltrated zirconia on the cementing surface and sintered; for biaxial flexural strength testing (ISO 6872:2015). A gel was synthesized via the sol-gel method and applied to the ceramic surface. Mechanical assay data (MPa) were evaluated via Weibull analysis (α = 5%) and specimens via X-Ray Diffractometry (XRD), Scanning Electron Microscopy (SEM), and fractographic analysis. The Zinf-tens group showed a characteristic strength of 824 MPa and m = 9.9; Zinf-comp 613 MPa and m = 10.2; Zctrl 534 MPa and m = 8; all groups differed statistically (σ0). However, they were similar in structural homogeneity (m). XRD showed 20-50 µm of infiltration, which means dissolution of part of the yttrium and reduction in the size of the cubic grains. In addition, the Zinf-tens group presented a failure origin from inside the material. The developed glass infiltrated into zirconia partially stabilized by yttrium oxide, increasing its characteristic strength and structural homogeneity by reducing surface defects and changing the failure mode.

King George III of England and Queen Maria I of Portugal: bipolar disorder and prince regents as common features of their reigns.

ABSTRACT: Humanity is sporadically subjected to leaders with deviant behavior, ego problems, or psychiatric disorders, potentially leading to social instability. Bipolar disorder is not common in all populations, but, coincidentally, studies suggest that it affected two sovereigns that were contemporaries, King George III of England, who died 201 years ago, and Queen Maria I of Portugal, who died 205 years ago. They lived during a time when Europe was in turmoil with the French Revolution and Napoleonic Wars, which also coincided with the rise of psychiatry. Both monarchs were forced to have prince regents rule in their place, due to their emotional decline, and they shared the same medical consultant, Francis Willis.

Extruded urea could replace true protein source in supplements for lambs finished in tropical pastures / A ureia extrusada pode substituir a fonte de proteína verdadeira em suplementos para cordeiros terminados em pastagens tropicais

The aim of this study was to evaluate the effects of replacing 50% of the true protein from soybean meal with extruded urea on the performance and carcass characteristics of lambs finished on pasture. Twenty lambs with initial weight of 29.9±6.2kg and 5 months of age, distributed in two treatments in blocks at random, were kept in pastures of Urochloa spp. Supplemented with 2% of body weight (BW). The treatments consisted of supplements containing soybean meal as the only true protein source (control), or extruded urea replacing 50% of soybean meal (NPN treatment). There was no effect of treatment on total supplement intake. There were differences in average daily gain (242.1 vs. 264.6g/day), slaughter weight (41.9 vs. 45.0kg) and carcass weight (18.9 vs. 20.1kg). There was no effect of the treatment on the final body condition score, hot carcass yield, carcass length, breast depth, subcutaneous fat thickness or rib eye area. The group of animals that received extruded urea showed superior carcass finishing characteristics (99.0% vs. 66.0%), maturity (22.0% vs. 0.0%), marbling (55.0% vs. 33.0%), meat texture (44.0% vs. 33.0%) and fat (66.0% vs. 22.0%). There were no significant effects on tenderness (7.5kg/f) or flesh color (L* = 33.2; a* = 16.2; b* = 8.3). There were no significant changes in the biochemical profile of the animals' blood during the experiment for both treatments. The replacement of 50% of protein from soybean meal by the extruded urea as NPN source in the supplement for lambs finished in Urochloa spp pastures provides better animal performance and qualitative characteristics of meat, without altering quantitative carcass characteristics.

Objetivou-se avaliar os efeitos da substituição de 50% da proteína verdadeira do farelo de soja por ureia extrusada sobre o desempenho e as características de carcaça de cordeiros terminados em pasto. Vinte cordeiros de 29,9+6,2kg de peso inicial e com cinco meses de idade, distribuídos em dois tratamentos em blocos ao acaso, foram mantidos em pastagens de Urochloa spp. suplementado com 2% do peso vivo (PV). Os tratamentos consistiram em suplementos contendo farelo de soja como única fonte de proteína verdadeira (controle), ou ureia extrusada em substituição a 50% do farelo de soja (tratamento NPN). Não houve efeito do tratamento na ingestão total de suplemento. Houve diferenças no ganho médio diário (242,1 vs. 264,6 g/dia), no peso ao abate (41,9 vs. 45,0kg) e no peso da carcaça (18,9 vs. 20,1kg). Não houve efeito do tratamento sobre escore de condição corporal final, rendimento de carcaça quente, comprimento de carcaça, profundidade do peito, espessura de gordura subcutânea ou área de olho de lombo. O grupo de animais que recebeu ureia extrusada apresentou características superiores de acabamento de carcaça (99,0% vs. 66,0%), maturidade (22,0% vs. 0,0%), marmoreio (55,0% vs. 33,0%), textura da carne (44,0% vs. 33,0%) e gordura (66,0% vs. 22,0%). Não houve efeitos significativos na maciez (7,5 kg/f) nem na cor da carne (L*= 33,2; a*= 16,2; b * = 8,3). Não houve mudanças significativas no perfil bioquímico do sangue dos animais durante o experimento para ambos os tratamentos. A substituição de 50% da proteína do farelo de soja pela ureia extrusada como fonte de NPN no suplemento para cordeiros terminados em pastagem de Urochloa spp. proporciona melhor desempenho animal e características qualitativas da carne, sem alterar as características quantitativas da carcaça.

Exposure to Pfaffia glomerata causes oxidative stress and triggers hepatic changes / Exposição a Pfaffia glomerata causa estresse oxidativo e desencadeia alterações hepáticas

Medicinal plant species are genetically engineered to obtain higher production of biomass and specific secondary metabolites, which can be used in the pharmaceutical industry. The aim of the present study was to evaluate the effect of Pfaffia glomerata (Spreng.) Pedersen tetraploid hydroalcoholic extract on the liver of adult Swiss mice. The extract was prepared from the plant roots and given to the animals by gavage, for 42 days. The experimental groups were treated with water (control), Pfaffia glomerata tetraploid hydroalcoholic extract (100, 200 and 400 mg/kg) and Pfaffia glomerata tetraploid hydroalcoholic extract discontinuously (200 mg/kg). The last group received the extract every 3 days, for 42 days. The oxidative status, mineral dynamics, and cell viability were analysed. The liver weight and the number of viable hepatocytes were reduced, despite the increased cell's number. Increased levels of malondialdehyde and nitric oxide, and changes in iron, copper, zinc, potassium, manganese and sodium levels were observed. aspartate aminotransferase levels were increased while alanine aminotransferase levels were decreased due to BGEt intake. Our results showed that BGEt induced alterations of oxidative stress biomarkers leading to liver injury, which was associated with a reduction in the number of hepatocytes.

Espécies de plantas medicinais são geneticamente modificadas para obter maior produção de biomassa e metabólitos secundários específicos, que podem ser utilizados na indústria farmacêutica. O objetivo do presente estudo foi avaliar o efeito do extrato hidroalcoólico tetraploide de Pfaffia glomerata no fígado de camundongos suíços adultos. O extrato foi preparado a partir das raízes das plantas e administrado aos animais por gavagem, por 42 dias. Os grupos experimentais foram tratados com água (controle), extrato hidroalcoólico de Pfaffia glomerata tetraploide (100, 200 e 400 mg/kg) e extrato hidroalcoólico de Pfaffia glomerata tetraploide de forma descontinua (200 mg/kg). O último grupo recebeu o extrato a cada 3 dias, durante 42 dias. O estado oxidativo, a dinâmica mineral e a viabilidade celular foram analisados. O peso do fígado e o número de hepatócitos foram reduzidos, apesar do aumento do número de células. Observou-se aumento dos níveis de malondialdeído e óxido nítrico e alterações nos níveis de Ferro, Cobre, Zinco, potássio, Magnésio e sódio. Os níveis de aspartato aminotransferase aumentaram, enquanto os níveis de alanina aminotransferase diminuíram devido à ingestão do extrato. Nossos resultados mostraram que BGEt induziu alterações de biomarcadores de estresse oxidativo levando a lesão hepática, que foi associada a uma redução no número de hepatócitos.

King George III of England and Queen Maria I of Portugal: bipolar disorder and prince regents as common features of their reigns

Abstract Humanity is sporadically subjected to leaders with deviant behavior, ego problems, or psychiatric disorders, potentially leading to social instability. Bipolar disorder is not common in all populations, but, coincidentally, studies suggest that it affected two sovereigns that were contemporaries, King George III of England, who died 201 years ago, and Queen Maria I of Portugal, who died 205 years ago. They lived during a time when Europe was in turmoil with the French Revolution and Napoleonic Wars, which also coincided with the rise of psychiatry. Both monarchs were forced to have prince regents rule in their place, due to their emotional decline, and they shared the same medical consultant, Francis Willis.

Transport properties in multilayer adsorption of dimers.

In this paper, we study the transport properties (percolation and conductivity) of a two-dimensional structure created by depositing dimers on a one-dimensional substrate where multilayer deposition is allowed. Specifically, we are interested in studying how the mentioned properties vary as a function of the height of the multilayer. The critical parameters of the percolation transition are calculated using finite-size scaling analysis, obtaining the scaling laws for the probability of percolation and the conductivity of the system. To calculate the electrical conductivity of the multilayer, we use the Frank-Lobb algorithm.

Unfolding of crumpled thin sheets.

Crumpled thin sheets are complex fractal structures whose physical properties are influenced by a hierarchy of ridges. In this paper, we report experiments that measure the stress-strain relation and show the coexistence of phases in the stretching of crumpled surfaces. The pull stress showed a change from a linear Hookean regime to a sublinear scaling with an exponent of 0.65±0.03, which is identified with the Hurst exponent of the crumpled sheets. The stress fluctuations are studied. The statistical distribution of force peaks is analyzed. It is shown that the unpacking of crumpled sheets is guided by a hierarchical order of ridges.

Magnitude of visceral leishmaniasis and HIV coinfection and association with social determinants of health in the Northeast region of Brazil: a retrospective, spatiotemporal model (2010-2018).

The Northeast region of Brazil (NRB) includes the states with the highest prevalence of visceral leishmaniasis (VL), as well as those with significant increases in HIV cases. This study aims to analyze the spatiotemporal patterns of VL-HIV coinfection and its association with the social determinants of health (SDH) in the NRB. Time trend analysis and Bayesian spatial statistical inferences, Moran's autocorrelation, and retrospective space-time scanning were performed. Spatial regression modelling was used to build an explanatory model for the occurrence of VL-HIV coinfection within NRB. A total of 1550 cases of VL-HIV coinfection were confirmed. We observed a higher prevalence among males (1232; 83%), individuals aged from 20 to 59 years (850; 54.8%), non-white skin color (1,422; 91.7%), and with low education (550; 35.48%). NRB showed an increasing and significant trend in the detection rate of coinfection (APC, 5.3; 95% CI, 1.4 to 9.4). The states of Maranhão and Piauí comprised the high-risk cluster. The SDH that most correlated with the occurrence of coinfection were poor housing, low income, and low education. VL-HIV is dispersed in the NRB but chiefly affects states with greater social vulnerability. Taken together, these findings reinforce the necessity to implement surveillance strategies that will contribute to the reduction of cases in these populations.

Correlation between renal ultrasonography and serum cystatin C in acute kidney disease of critically ill dogs / Correlação entre a ultrassonografia e a determinação da cistatina C sérica em cães admitidos em unidade de terapia

Acute kidney injury (AKI) is defined as the rapid decline in kidney function. Its development is related to critical clinical statuses, such as sepsis, complicated post-surgical recovery, and infectious diseases. Serum cystatin C (CysC) has the best correlation with the glomerular filtration rate. Ultrasonography stands out because it is highly accessible and can be done at the bedside. Twenty-eight dogs admitted to the intensive care unit with serum creatinine values <1.6 mg/dL and at-risk factors of AKI development were selected. CysC measurements and ultrasound assessments were performed daily for 72 hours. Using CysC dosage, 22/28 animals (78.6%) were considered to have AKI, and 17/22 had ultrasound compatible with AKI changes, demonstrating moderate agreement with CysC dosage. Increased cortical renal echogenicity is the most prevalent alteration in critically ill patients and is correlated with serum increases in CysC and is associated with renal structural damage.

A injúria renal aguda (IRA) é definida como o declínio rápido da função renal. Seu desenvolvimento está relacionado a quadros clínicos críticos, como sepse, pós-operatório complicado e doenças infecciosas. A cistatina C sérica (CisC) tem melhor correlação com taxa de filtração glomerular. A ultrassonografia se destaca por ser altamente acessível e pode ser realizada à beira do leito. Foram selecionados 28 cães, internados em unidade de terapia intensiva, com valores de creatinina sérica <1,6mg/dL e fatores de risco para o desenvolvimento de IRA. Medições de CisC e avaliações ultrassonográficas foram realizadas diariamente por 72 horas. Utilizando-se a dosagem de CisC, 22/28 animais (78,6%) foram considerados portadores de IRA e 17/22 apresentaram ultrassom compatível com alterações de IRA, demonstrando concordância moderada com a dosagem de CisC. O aumento da ecogenicidade cortical renal é a alteração mais prevalente em pacientes críticos, está correlacionado com aumentos séricos de CisC e associado a dano estrutural renal.

Monitoring of Leptospira in captive turtles by DNA analysis / [Monitoramento de Leptospira em quelônios mantidos em cativeiro pela análise de DNA]

Existem poucos estudos sobre doenças infecciosas em animais silvestres. O objetivo deste estudo foi pesquisar DNA de Leptospira spp. em sangue de tartarugas mantidas em cativeiro, pertencentes ao Bosque Rodrigues Alves (Jardim Zoobotânico da Amazônia). O DNA foi isolado das amostras de sangue coletadas de 148 tartarugas pertencentes a seis espécies diferentes. A reação em cadeia da polimerase (PCR) foi realizada utilizando-se iniciadores específicos para DNA de Leptospira spp. Nenhuma das amostras apresentou resultado positivo para Leptospira spp.(AU)

Effects of photobiomodulation and swimming on gene expression in rats with the tibialis anterior muscle injury.

The aim of the present study was to evaluate the effects of photobiomodulation (low-level laser therapy (LLLT)) and aquatic exercise on the expression of genes related to muscle regeneration in rats. Wistar rats were divided into five groups: control group (n = 15), non-treated injury group (n = 15), injury+LLLT group (n = 15), injury+aquatic exercise group (n = 15), and injury+LLLT+aquatic exercise group (n = 15). Cryoinjury was performed on the belly of the tibialis anterior (TA) muscle. LLLT was performed daily with an AlGaAs laser (830 nm; beam spot of 0.0324 cm2, output power of 100 mW, energy density of 180 J/cm2, and 58-s exposure time). Animals were euthanized at 7, 14, and 21 days. The TA muscles were removed for gene expression analysis of TGF-ß, Myogenin, and MyoD. The results were statistically analyzed at a significance level of 5%. The cryoinjury increased the expression of genes related to muscle regeneration-MyoD, Myogenin, and TGF-ß-compared to the control group (p < 0.05); the photobiomodulation increased the expression of these genes at day 7 (p < 0.05), decreasing until day 21; and the aquatic exercise increases the expression of the three genes over time. When the two treatments were combined, the expression of the analyzed genes also increased over time. In summary, the results of our study suggest that photobiomodulation (LLLT), when applied alone in cryoinjury, is able to increase the gene expression of MyoD, Myogenin, and TGF-ß at the acute phase, while when combined with aquatic exercises, there is an increase in expression of these genes specially at the long-term treatment.

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.

Genomic ancestry and metabolic syndrome in individuals with type 1 diabetes from an admixed population: a multicentre, cross-sectional study in Brazil.

AIMS: To evaluate the relationship between self-reported colour-race, genomic ancestry, and metabolic syndrome in an admixed Brazilian population with type 1 diabetes. METHODS: We included 1640 participants with type 1 diabetes. The proportions of European, African and Amerindian genomic ancestries were determined by 46 ancestry informative markers of insertion deletion. Two different sets of analyses were performed to determine whether self-reported colour-race and genomic ancestry were predictors of metabolic syndrome. RESULTS: Metabolic syndrome was identified in 29.8% of participants. In the first model, the factors associated with metabolic syndrome were: female gender (odds ratio 1.95, P < 0.001); diabetes duration (odds ratio 1.04, P < 0.001); family history of type 2 diabetes (odds ratio 1.36, P = 0.019); and acanthosis nigricans (odds ratio 5.93, P < 0.001). Colour-race was not a predictive factor for metabolic syndrome. In the second model, colour-race was replaced by European genomic ancestry. The associated factors were: female gender (odds ratio 1.95, P < 0.001); diabetes duration (odds ratio 1.04, P < 0.001); family history of type 2 diabetes (odds ratio 1.39, P = 0.011); and acanthosis nigricans (odds ratio 6.12, P < 0.001). Physical exercise (≥3 times a week) was a protective factor (odds ratio 0.77, P = 0.041), and European genomic ancestry was not associated with metabolic syndrome but showed an odds ratio of 1.77 (P = 0.05). CONCLUSIONS: Although a higher level of European genomic ancestry was observed among participants with metabolic syndrome in the univariate analysis, this association did not persist after multivariable adjustments. Further prospective studies in other highly admixed populations remain necessary to better evaluate whether the European ancestral component modulates the development of metabolic syndrome in type 1 diabetes.

The global prevalence of apical periodontitis: a systematic review and meta-analysis.

BACKGROUND: Apical periodontitis (AP) frequently presents as a chronic asymptomatic disease. To arrive at a true diagnosis, in addition to the clinical examination, it is mandatory to undertake radiographic examinations such as periapical or panoramic radiographs, or cone-beam computed tomography (CBCT). Thus, the worldwide burden of AP is probably underestimated or unknown. Previous systematic reviews attempted to estimate the prevalence of AP, but none have investigated which factors may influence its prevalence worldwide. OBJECTIVES: To assess: (i) the prevalence of AP in the population worldwide, as well as the frequency of AP in all teeth, nontreated teeth and root filled teeth; (ii) which factors can modify the prevalence of AP. METHODS: A search was conducted in the PubMed-MEDLINE, EMBASE, Cochrane-CENTRAL, LILACS, Google scholar and OpenGrey databases, followed by hand searches, until September 2019. Cross-sectional, case-control and cohort studies reporting the prevalence of AP in humans, using panoramic or periapical radiograph or CBCT as image methods were included. No language restriction was applied. An adaptation of the Newcastle-Ottawa Scale was used to evaluate the quality of the studies. A meta-analysis was performed to determine the pooled prevalence of AP at the individual level. Secondary outcomes were the frequency of AP in all teeth, nontreated teeth and rootfilled teeth. Subgroup analyses using random-effect models were carried out to analyse the influence of explanatory covariables on the outcome. RESULTS: The search strategy identified 6670 articles, and 114 studies were included in the meta-analysis, providing data from 34 668 individuals and 639 357 teeth. The prevalence of AP was 52% at the individual level (95% CI 42%-56%, I2  = 97.8%) and 5% at the tooth level (95% CI 4%-6%; I2  = 99.5%). The frequency of AP in root-filled teeth and nontreated teeth was 39% (95% CI 36%-43%; I2  = 98.5%) and 3% (95% CI 2%-3%; I2  = 99.3%), respectively. The prevalence of AP was greater in samples from dental care services (DCS; 57%; 95% CI 52%-62%; I2  = 97.8%) and hospitals (51%; 95% CI 40%-63%; I2  = 95.9%) than in those from the general population (GP; 40%; 95% CI 33%-46%; I2  = 96.5%); it was also greater in people with a systemic condition (63%; 95% CI 56%-69%, I2  = 89.7%) compared to healthy individuals (48%; 95% CI 43%-53%; I2  = 98.3%). DISCUSSION: The subgroup analyses identified explanatory factors related to the variability in the prevalence of AP. However, the high clinical heterogeneity and high risk of bias across the primary studies indicate that the findings must be interpreted with caution. CONCLUSIONS: Half of the adult population worldwide have at least one tooth with apical periodontitis. The prevalence of AP is greater in samples from the dental care services, but it is also high amongst community representative samples from the general population. The present findings should bring the attention of health policymakers, medical and dental communities to the hidden burden of endodontic disease in the population worldwide.

Saccharomyces boulardii as therapeutic alternative in experimental giardiasis.

AIMS: The objective of this study was to evaluate the effect of treatment with the probiotic Saccharomyces boulardii with or without metronidazole in experimental giardiasis. METHODS AND RESULTS: The effect of treatment with S. boulardii with or without metronidazole on the intestinal mucosa, the antioxidant defence system and the parasitic load was determined in experimental giardiasis. Eight groups of animals with infection and/or treatment with the probiotic and/or drugs for 1 week after infection with Giardia lamblia were used. A reduction of approximately 90% in the parasitic load was observed in all the treated groups. Saccharomyces boulardii attenuated the damage caused by infection in the intestinal mucosa preserving its architecture and inhibiting the oxidative stress induced by parasite and metronidazole. CONCLUSIONS: Saccharomyces boulardii was effective alone or in combination with metronidazole in resolving already established G. lamblia infection. SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggest the use of S. boulardii as an alternative treatment for giardiasis mainly in cases of resistance or intolerance to conventional treatment.