University of São Paulo
  • São Paulo, Estado de Sao Paulo, Brazil
Recent publications
This study aims to evaluate the effectiveness of an online course to enable orthopaedic surgeons to acquire the core competencies necessary to prevent and treat fracture-related infections (FRI). This study included orthopaedic surgeons and residents from Latin American countries who attended an online course focused on FRI. The online course included: didactic lectures, small-group clinical case discussions, and panel case discussions. The course was delivered using Zoom® platform and designed to address four core competencies: prevention, definition and diagnosis, antimicrobial therapy, and surgical treatment. An online questionnaire was created distributing 16 questions through six clinical scenarios. Participants were invited to answer the questionnaire before and after the course. Sixty of the 78 course participants answered the pre-course, and 42 the post-course assessment. Relative to before the course, the mean post-course assessment score rose significantly for prevention of FRI (4.1 before and 4.5 after; p = 0.014), definition and diagnosis (2.4 before and 3.4 after; p = 0.001), and surgical treatment (2.2 before and 2.8 after; p = 0.011). The final score encompassing all four core competencies also rose significantly (2.7 before and 3.3 after; p = 0.001). The online course on FRI was feasible and effective, significantly increasing course users’ knowledge of overall competency in managing FRI.
Pediocin PA-1 is a class IIa bacteriocin that is particularly effective against the foodborne pathogen Listeria monocytogenes. The loss of activity of PA-1 pediocin due to methionine oxidation is one of the challenges that limit the wider application of the bacteriocin. In this study, we heterologously expressed an oxidation resistant form of pediocin PA-1, i.e., pediocin M31L, and compared its activity to that of native pediocin PA-1 and to penocin A, a pediocin-like bacteriocin that displays a narrower antimicrobial spectrum. Minimal inhibitory concentration assays revealed that pediocin M31L was as effective as PA-1 and more effective than synthetic penocin A against Listeria with negligible activity against a range of obligate anaerobic commensal gut bacterial species. The anti-Listeria activity of these pediocins was also assessed in a simulated human distal colon model assay using the L. monocytogenes, spiked at 6.5 ± 0.13 Log CFU/mL, as a bioindicator. At 24 h, pediocin M31L and penocin A (2.6 μM) reduced Listeria counts to 3.5 ± 0.4 and 3.64 ± 0.62 Log CFU/mL, respectively, whereas Listeria counts were considerably higher, i.e. 7.75 ± 0.43 Log CFU/mL, in the non-bacteriocin-containing control. Ultimately, it was established that synthetic penocin A and the stable pediocin M31L derivative, heterologously produced, display effective anti-Listeria activity in a human gut environment.
Introduction: Bonding to crystalline zirconia is currently a challenge. Properly cured adhesives are crucial to optimize this bond, and that in turn is influenced by the initial mobility of the system, as well as by the reactivity of the initiators. Aim: This study aimed to characterize adhesives containing monomer mixtures of different viscosities and double and triple photoinitiator systems; and to evaluate the bonding to Y-TZP zirconia, when adhesives were light-activated with monowave or polywave light-curing units (LCU). Materials and methods: Adhesives were formulated at a 1:1 weight proportion of Bis-GMA/TEGDMA or Bis-GMA/Bis-EMA. To these mixtures 0.5 wt% of CQ, 0.5-1.0 wt% of DABE, 0.5-1.0 wt% of DPIHP, or 0.5-1.0 wt% of TAS-Sb were added and used as photoinitiator systems. A total of ten adhesives were prepared. Resin composite cylinders were cemented on zirconia slices and 6000 thermal cycles were performed. Degree of conversion (DC), sorption (SO) and solubility (SL) after 7 days of water storage, and microshear bond strength (µSBS) were evaluated. Data were analyzed with three-way ANOVA and Tukey's HSD (α = 0.05). Results: Bis-GMA/Bis-EMA combined with either CQ/DABE or CQ/DABE/TAS-Sb presented the highest DC, and no significant differences were observed for LCUs (p = .298). CQ/DABE < CQ/DABE/TAS-Sb ≈ CQ/DABE/DPIHP and the polywave LCU showed smaller overall SO (p < .05). Bis-GMA/TEGDMA with CQ/DABE cured with the polywave LCU presented the lowest SO. SL varied as follows: CQ/DABE/TAS-Sb < CQ/DABE/DPIHP < CQ/DABE (p < .001). For µSBS, only the factor photoinitiator system was significant (p = .045). All mean values were above 30 MPa, with higher values being observed for BIS-GMA/TEGDMA and CQ/DABE. Conclusion: It can be concluded that the adhesive containing CQ/DABE/TAS-Sb as coinitiator of Bis-GMA/Bis-EMA mixtures produced a material with higher DC and lower SL, while bond strength values were similar to the ones obtained by CQ/DABE.
The phytochemical study of the hydroethanolic extract of green propolis produced by Apis mellifera in the Northeastern Brazilian Caatinga from Mimosa tenuiflora led to the isolation of sixteen flavonoids, including eleven flavonols 1–11, four flavanones 12–15, and one prenylated flavanone 16. It is the first time they were isolated from the green propolis of Caatinga M. tenuiflora. Flavonols 2–3, and 5–11, and flavanones 14–16 were first isolated from the genus Mimosa, as well as ermanin (2), axillarin (5), eriodictyol 5-Omethyl ether (13), and 5,4′-dihydroxy-6,7-dimethoxyflavanone (14) have never been observed in the family Fabaceae related materials before. HPLC analysis of the hydroalcoholic extracts confirmed M. tenuiflora as the primary botanical source of Caatinga green propolis. Chemotaxonomic significance is discussed in detail.
Recent literature emphasizes how the specific stressors of the COVID-19 outbreak affect the general population and frontline professionals, including those conducting support or backup activities in health units, which can lead to vicarious traumatization. Vicarious traumatization has been used to describe negative emotional reactions in mental health professionals who assist or treat victims of traumatic events. Thus, the aim of this article is to report the actions used in the face of the psychological demands of professionals in a hospital, who were not on the frontline of COVID-19. We collected their sociodemographic information and checked the psychological impact using the depression, anxiety, and stress scale (DASS-21), which was followed by a psychoeducational program (topics related to COVID-19 control and prevention), and individual psychological care for the most severe cases. A total of 118 professionals participated in this study; they were between 20 and 67 years old. Mild to moderate anxiety was observed in 36.5% of the medical teams, 83.3% of the administrative staff, and 65.7% of general service workers, while stress symptoms were observed in 80.2%, 83.3%, and 59.9%, respectively. Depressive symptoms (35.3%) were more frequent in general service workers. The medical teams reported the benefits of primary psychological care, while the other professionals demanded more institutional support services related to the prevention and use of personal protective equipment. This study highlights relevant psychological demands that have repercussions on the daily lives of professionals. The psychoeducational program was considered positive regarding clarification actions. However, it was not perceived as effective in reducing fear, which may result from vicarious traumatization and requires other intervention modalities.
Background The tomographic finding, which has been called the "fingerprint sign" in en face reconstructions, seems to be the result of a variety of processes that cause distension of the outer plexiform layer (OPL) and the Henle fiber layer (HFL). The aim of this paper is to describe the appearance of concentric rings at the OPL/HFL interface visualized using en face reconstructions of cross-sectional optical coherence tomography images of patients with Vogt-Koyanagi-Harada disease. Methods Retrospective analysis of images of six eyes of three patients obtained by cross-sectional OCT imaging and en face reconstruction at the level of the OPL/HFL interface. Results All eyes presented with a dentate or saw-tooth pattern of the OPL/HFL interface on cross-sectional OCT with corresponding concentric rings on en face OCT reconstruction, consistent with the recently published “fingerprint sign”. Initial OPL/HFL interface changes were observed between the first and fourth months after treatment and resolution of VKHD associated serous retinal detachments. These OPL/HFL interface changes have persisted for many years following the resolution of the active inflammation. Conclusions Changes in the OPL/HFL interface can be identified following successful treatment of VKHD. These included both a dentate or saw-tooth pattern on cross-sectional imaging and concentric rings or the “fingerprint sign” on en face reconstructions. These changes persisted for many years despite disease quiescence.
Gait issues in Parkinson’s disease (PD) are common and can be highly disabling. Although levodopa and deep brain stimulation (DBS) of the subthalamic nucleus and the globus pallidus internus have been established therapies for addressing the motor symptoms of PD, their effects on gait are less predictable and not well sustained with disease progression. Given the high prevalence of gait impairment in PD and the limitations in currently approved therapies, there has been considerable interest in alternative neuromodulation targets and techniques. These have included DBS of pedunculopontine nucleus and substantia nigra pars reticulata, spinal cord stimulation, non-invasive modulation of cortical regions and, more recently, vagus nerve stimulation. However, successes and failures have also emerged with these approaches. Current gaps and controversies are related to patient selection, optimal electrode placement within the target, placebo effects and the optimal programming parameters. Additionally, recent advances in pathophysiology of oscillation dynamics have driven new models of closed-loop DBS systems that may or may not be applicable to gait issues. Our aim is to describe approaches, especially neuromodulation procedures, and emerging challenges to address PD gait issues beyond subthalamic nucleus and the globus pallidus internus stimulation.
Background Brain abnormalities are a concern in COVID-19, so we used minimally invasive autopsy (MIA) to investigate it, consisting of brain 7T MR and CT images and tissue sampling via transethmoidal route with at least three fragments: the first one for reverse transcription polymerase chain reaction (RT-PCR) analysis and the remaining fixed and stained with hematoxylin and eosin. Two mouse monoclonal anti-coronavirus (SARS-CoV-2) antibodies were employed in immunohistochemical (IHC) reactions. Results Seven deceased COVID-19 patients underwent MIA with brain MR and CT images, six of them with tissue sampling. Imaging findings included infarcts, punctate brain hemorrhagic foci, subarachnoid hemorrhage and signal abnormalities in the splenium, basal ganglia, white matter, hippocampi and posterior cortico-subcortical. Punctate brain hemorrhage was the most common finding (three out of seven cases). Brain histological analysis revealed reactive gliosis, congestion, cortical neuron eosinophilic degeneration and axonal disruption in all six cases. Other findings included edema (5 cases), discrete perivascular hemorrhages (5), cerebral small vessel disease (3), perivascular hemosiderin deposits (3), Alzheimer type II glia (3), abundant corpora amylacea (3), ischemic foci (1), periventricular encephalitis foci (1), periventricular vascular ectasia (1) and fibrin thrombi (1). SARS-CoV-2 RNA was detected with RT-PCR in 5 out of 5 and IHC in 6 out 6 patients (100%). Conclusions Despite limited sampling, MIA was an effective tool to evaluate underlying pathological brain changes in deceased COVID-19 patients. Imaging findings were varied, and pathological features corroborated signs of hypoxia, alterations related to systemic critically ill and SARS-CoV-2 brain invasion.
Background COVID-19 has affected millions of people worldwide. Clinical manifestations range from severe cases with lethal outcome to mild or asymptomatic cases. Although the proportion of infected individuals does not differ between sexes, men are more susceptible to severe COVID-19, with a higher risk of death than women. Also, men are pointed out as more lax regarding protective measures, mask wearing and vaccination. Thus, we questioned whether sex-bias may be explained by biological pathways and/or behavioral aspects or both. Methods Between July 2020 and July 2021, we performed an epidemiological survey including 1744 unvaccinated adult Brazilian couples, with there was at least one infected symptomatic member, who were living together during the COVID-19 infection without protective measures. Presence or absence of infection was confirmed by RT-PCR and/or serology results. Couples were divided into two groups: (1) both partners were infected (concordant couples) and (2) one partner was infected and the spouse remained asymptomatic despite the close contact with the COVID-19 symptomatic partner (discordant couples). Statistical analysis of the collected data was performed aiming to verify a differential transmission potential between genders in couples keeping contact without protective measures. Results The combination of our collected data showed that the man is the first (or the only) affected member in most cases when compared to women and that this difference may be explained by biological and behavioral factors. Conclusions The present study confirmed the existence of gender differences not only for susceptibility to infection and resistance to COVID-19 but also in its transmission rate.
The Brazilian agro-industrial chain generates about 291 million/tons/year of wastes, which, if inadequately destinated, could originate social and environmental risks. There is a growing need for the use of alternative raw materials to replace that originated from fossil resources in the Brazilian industry. Renewable materials play an important role on the sustainability of ecosystems and materials’ circularity. The issue has acquired importance in light of recent bio-based agro-fiber development potential applications. Considering sustainability guidelines, this study aimed to analyze the main Brazilian agro-industrial waste crops (temporary and permanent) as important sources of natural fibers and other raw materials. A systematic review of the literature (SRL) about Brazilian researches, based on concepts of industrial ecology, and the creation of a bibliometric analysis network were carried out. The agricultural biomass related to the main crops presents characteristics making them suitable to be applied for textiles, as natural fibers and polymers, in biosorbents for industrial effluents, and cellulose obtention and reinforcement material in composites. Thus, scientific investment in researches on materials and technology development are necessary to provide applications that could meet current and future demands and expand the scope of new materials for sustainability.
Fabric-reinforced cementitious matrix (FRCM) with synthetic reinforcements has been employed in a wide of precast products in the current market. However, FRCM employing cellulosic fibers has been limited in civil engineering applications due to the absence of a well-established standardization. Cellulosic textile structures present many advantages to strengthen cementitious composites, which depend on the type of natural fiber, forms that are organized (e.g., bundle fibers or twisted yarns), and ligaments. This study aimed to develop an overview of FRCM to identify how cellulosic textile has been designed and processed in research, according to type, shape, properties, durability, and matrix formulations. The main findings were as follows: (i) bundle fibers and low entangled yarns presented potential to increase the tensile properties; (ii) woven canvas prevailed in the cementitious composite applications; (iii) 3 and 4 layers of fabrics presented better mechanical performance than few layer samples; (iv) the alkaline treatment is one of most employment to improve the adherence; (v) to prevent cellulose degradation, resin coatings (epoxy) or pozzolan additions (silica, metakaolin, nanoclay, ashes from agricultural wastes) are employed. Future investigations are necessary to improve cellulosic FRCM; opportunities for study in textile area are proposed: enlargement of fabric technologies, hybrid fibers, machinery technology (3D fabrics, complex knit) adaptation to use cellulosic fibers, and new architectural design for cellulosic FRCM applications (curved forms and sizes).
The accurate simulation of additional interactions at the ATLAS experiment for the analysis of proton–proton collisions delivered by the Large Hadron Collider presents a significant challenge to the computing resources. During the LHC Run 2 (2015–2018), there were up to 70 inelastic interactions per bunch crossing, which need to be accounted for in Monte Carlo (MC) production. In this document, a new method to account for these additional interactions in the simulation chain is described. Instead of sampling the inelastic interactions and adding their energy deposits to a hard-scatter interaction one-by-one, the inelastic interactions are presampled, independent of the hard scatter, and stored as combined events. Consequently, for each hard-scatter interaction, only one such presampled event needs to be added as part of the simulation chain. For the Run 2 simulation chain, with an average of 35 interactions per bunch crossing, this new method provides a substantial reduction in MC production CPU needs of around 20%, while reproducing the properties of the reconstructed quantities relevant for physics analyses with good accuracy.
Background Transcription factors (TFs) are proteins controlling the flow of genetic information by regulating cellular gene expression. A better understanding of TFs in a bacterial community context may open novel revenues for exploring gene regulation in ecosystems where bacteria play a key role. Here we describe PredicTF, a platform supporting the prediction and classification of novel bacterial TF in single species and complex microbial communities. PredicTF is based on a deep learning algorithm. Results To train PredicTF, we created a TF database (BacTFDB) by manually curating a total of 11,961 TF distributed in 99 TF families. Five model organisms were used to test the performance and the accuracy of PredicTF. PredicTF was able to identify 24–62% of the known TFs with an average precision of 88% in our five model organisms. We demonstrated PredicTF using pure cultures and a complex microbial community. In these demonstrations, we used (meta)genomes for TF prediction and (meta)transcriptomes for determining the expression of putative TFs. Conclusion PredicTF demonstrated high accuracy in predicting transcription factors in model organisms. We prepared the pipeline to be easily implemented in studies profiling TFs using (meta)genomes and (meta)transcriptomes. PredicTF is an open-source software available at .
There are many claims that gamification (i.e., using game elements outside games) impact decreases over time (i.e., the novelty effect). Most studies analyzing this effect focused on extrinsic game elements, while fictional and collaborative competition have been recently recommended. Additionally, to the best of our knowledge, no long-term research has been carried out with STEM learners from introductory programming courses (CS1), a context that demands encouraging practice and mitigating motivation throughout the semester. Therefore, the main goal of this work is to better understand how the impact of a gamification design, featuring fictional and competitive-collaborative elements, changes over a 14-week period of time, when applied to CS1 courses taken by STEM students (N = 756). In an ecological setting, we followed a 2x7 quasi-experimental design, where Brazilian STEM students completed assignments in either a gamified or non-gamified version of the same system, which provided the measures (number of attempts, usage time, and system access) to assess user behavior at seven points in time. Results indicate changes in gamification’s impact that appear to follow a U-shaped pattern. Supporting the novelty effect, the gamification’s effect started to decrease after four weeks, decrease that lasted between two to six weeks. Interestingly, the gamification’s impact shifted to an uptrend between six and 10 weeks after the start of the intervention, partially recovering its contribution naturally. Thus, we found empirical evidence supporting that gamification likely suffers from the novelty effect, but also benefits from the familiarization effect, which contributes to an overall positive impact on students. These findings may provide some guidelines to inform practitioners about how long the initial contributions of gamification last, and how long they take to recover after some reduction in benefits. It can also help researchers to realize when to apply/evaluate interventions that use gamification by taking into consideration the novelty effect and, thereby, better understand the real impact of gamification on students’ behavior in the long run.
The Brazilian Policy of Comprehensive Care for People with Rare Diseases (BPCCPRD) was established by the Ministry of Health to reduce morbidity and mortality and improve the quality of life of people with rare diseases (RD). Several laboratory tests, most using molecular genetic technologies, have been incorporated by the Brazilian Public Health System, and 18 specialised centres have so far been established at university hospitals (UH) in the capitals of the Southern, Southeastern and Northeastern regions. However, whether the available human and technological resources in these services are appropriate and sufficient to achieve the goals of care established by the BPCCPRD is unknown. Despite great advances in diagnosis, especially due to new technologies and the recent structuring of clinical assessment of RD in Brazil, epidemiological data are lacking and when available, restricted to specific disorders. This position paper summarises the performance of a nationally representative survey on epidemiology, clinical status, and diagnostic and therapeutic resources employed for individuals with genetic and non-genetic RD in Brazil. The Brazilian Rare Disease Network (BRDN) is under development, comprising 40 institutions, including 18 UH, 17 Rare Diseases Reference Services and five Newborn Screening Reference Services. A retrospective study will be initially conducted, followed by a prospective study. The data collection instrument will use a standard protocol with sociodemographic data and clinical and diagnostic aspects according to international ontology. This great collaborative network is the first initiative of a large epidemiological data collection of RD in Latin America, and the results will increase the knowledge of RD in Brazil and help health managers to improve national public policy on RD in Brazil.
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Daniel Cordeiro
  • School of Arts, Sciences and Humanities
Charles Lourenco
  • Departamento de Neurociências e Ciências do Comportamento (Ribeirão Preto)
Rua da Reitoria, 374, 05508-010, São Paulo, Estado de Sao Paulo, Brazil
Head of institution
Reitoria da Universidade de São Paulo