Current Understanding of Human Polymorphism in Selenoprotein Genes: A Review of Its Significance as a Risk Biomarker.

Selenium has been proven to influence several biological functions, showing to be an essential micronutrient. The functional studies demonstrated the benefits of a balanced selenium diet and how its deficiency is associated with diverse diseases, especially cancer and viral diseases. Selenium is an antioxidant, protecting the cells from damage, enhancing the immune system response, preventing cardiovascular diseases, and decreasing inflammation. Selenium can be found in its inorganic and organic forms, and its main form in the cells is the selenocysteine incorporated into selenoproteins. Twenty-five selenoproteins are currently known in the human genome: glutathione peroxidases, iodothyronine deiodinases, thioredoxin reductases, selenophosphate synthetase, and other selenoproteins. These proteins lead to the transport of selenium in the tissues, protect against oxidative damage, contribute to the stress of the endoplasmic reticulum, and control inflammation. Due to these functions, there has been growing interest in the influence of polymorphisms in selenoproteins in the last two decades. Selenoproteins' gene polymorphisms may influence protein structure and selenium concentration in plasma and its absorption and even impact the development and progression of certain diseases. This review aims to elucidate the role of selenoproteins and understand how their gene polymorphisms can influence the balance of physiological conditions. In this polymorphism review, we focused on the PubMed database, with only articles published in English between 2003 and 2023. The keywords used were "selenoprotein" and "polymorphism". Articles that did not approach the theme subject were excluded. Selenium and selenoproteins still have a long way to go in molecular studies, and several works demonstrated the importance of their polymorphisms as a risk biomarker for some diseases, especially cardiovascular and thyroid diseases, diabetes, and cancer.

Predictors of Trypanosoma cruzi PCR positivity in patients with chronic Chagas disease.

BACKGROUND: A positive Trypanosoma cruzi polymerase chain reaction (PCR) is associated with a worse prognosis in patients with chronic Chagas disease (CD). OBJECTIVES: To study the association of clinical, electrocardiographic, and echocardiographic characteristics and biomarker blood levels with positive T. cruzi PCR in chronic CD. METHODS: This is a single-centre observational cross-sectional study. Positive T. cruzi PCR association with clinical, electrocardiographic, and echocardiographic characteristics, and biomarker blood levels were studied by logistic regression analysis. p values < 0.05 were considered significant. FINDINGS: Among 333 patients with chronic CD (56.4% men; 62 ± 10 years), T. cruzi PCR was positive in 41.1%. Stepwise multivariate logistic regression showed an independent association between positive T. cruzi PCR and diabetes mellitus {odds ratio (OR) 0.53 [95% confidence interval (CI) 0.30-0.93]; p = 0.03}, right bundle branch block [OR 1.78 (95% CI 1.09-2.89); p = 0.02], and history of trypanocidal treatment [OR 0.13 (95% CI 0.04-0.38); p = 0.0002]. Among patients with a history of trypanocidal treatment (n = 39), only four (10%) patients had a positive T. cruzi PCR. MAIN CONCLUSIONS: Among several studied parameters, only diabetes mellitus, right bundle branch block, and history of trypanocidal treatment showed an independent association with positive T. cruzi PCR. History of trypanocidal treatment was a strong protective factor against a positive T. cruzi PCR.

In vitro evaluation of nanocomposites of linseed mucilage and k-carrageenan loaded with Achyrocline satureioides nanoemulsion: a gradual-release candidate of antimicrobials for the treatment of bovine mastitis.

This research paper presents the development and evaluation of pioneering nanocomposites (NCs) based on the combination of k-carrageenan and linseed mucilage. When loaded with macela extract nanoemulsion they present an innovative approach for the sustained release of antimicrobial herbal constituents, specifically tailored for bovine mastitis treatment. The NCs, encompassing various ratios of k-carrageenan and linseed mucilage polymers (8:2, 7:3, and 5:5 w/w) with 1.25 mg of macela extract/g of gel, underwent in vitro assessment, emphasizing viscosity, degradation speed, release of herbal actives from macela nanoemulsion and antimicrobial activity. The NCs exhibited thermoreversible characteristics, transitioning from liquid at 60°C to a gel at 25°C. NCs allowed a gradual release of phenolic compounds, reaching approximately 80% of total phenolics release (w/v) within 72 h. NCs inhibited the growth of MRSA (ATCC 33592) until 8 h of incubation. No toxic effect in vitro of NCs was found on MAC-T cells. Thus, the developed materials are relevant for the treatment of bovine mastitis, especially in the dry period, and the data support future evaluations in vivo.

Unveiling Lovastatin's Anti-Inflammatory Potential in Mouse's Brain during Acute Trypanosoma cruzi Infection.

Neurological commitment is a neglected manifestation of Chagas disease (CD). Meningoencephalitis mainly affects children and immunosuppressed patients, while stroke can occur with or without cardiac compromise. One of the possible causes of stroke development is microvascular commitment. Our group previously described that experimental Trypanossoma cruzi acute infection leads to cerebral microvasculopathy. This condition is characterized by decreased capillary density, increased leukocyte rolling and adhesion, and endothelial dysfunction. CD was discovered 114 years ago, and until today, only two drugs have been available for clinical treatment: benznidazole and nifurtimox. Both present a high cure rate for the acute phase (80%) and small cure rate for the chronic phase (20%). In addition, the high occurrence of side-effects, without proper medical follow-up, can result in treatment abandonment. Therefore, the search for new therapeutic schemes is necessary. Statins are drugs already used in the clinic that have several pleiotropic effects including endothelial function improvement, anti-inflammatory action, as well as trypanocidal effects, making them a potential alternative treatment for brain microvasculopathy in CD. Here, we investigate the effect of lovastatin (LOV) on brain microvasculopathy and inflammatory parameters. Swiss Webster mice were intraperitoneally inoculated with the Y strain of T. cruzi. Treatment with lovastatin (20 mg/kg/day) was initiated 24 h after the infection and continued for 14 consecutive days. We observed that LOV treatment did not affect parasitemia, brain microcirculation alterations, or the reduction in cerebral blood flow caused by T. cruzi infection. Also, LOV did not prevent the increased number of CD3+ cells and eNOS levels in the T. cruzi-infected brain. No alterations were observed on VCAM-1 and MCP-1 expressions, neither caused by infection nor LOV treatment. However, LOV prevented the increase in F4/80+ cells and ICAM-1 levels in the brain caused by acute infection with T. cruzi. These results suggest an anti-inflammatory activity of LOV, but more studies are needed to elucidate the role of LOV in CD acute infection.

Spheroid Model of Mammary Tumor Cells: Epithelial-Mesenchymal Transition and Doxorubicin Response.

Breast cancer is the most prevalent cancer among women worldwide. Therapeutic strategies to control tumors and metastasis are still challenging. Three-dimensional (3D) spheroid-type systems more accurately replicate the features of tumors in vivo, working as a better platform for performing therapeutic response analysis. This work aimed to characterize the epithelial-mesenchymal transition and doxorubicin (dox) response in a mammary tumor spheroid (MTS) model. We evaluated the doxorubicin treatment effect on MCF-7 spheroid diameter, cell viability, death, migration and proteins involved in the epithelial-mesenchymal transition (EMT) process. Spheroids were also produced from tumors formed from 4T1 and 67NR cell lines. MTSs mimicked avascular tumor characteristics, exhibited adherens junction proteins and independently produced their own extracellular matrix. Our spheroid model supports the 3D culturing of cells isolated from mice mammary tumors. Through the migration assay, we verified a reduction in E-cadherin expression and an increase in vimentin expression as the cells became more distant from spheroids. Dox promoted cytotoxicity in MTSs and inhibited cell migration and the EMT process. These results suggest, for the first time, that this model reproduces aspects of the EMT process and describes the potential of dox in inhibiting the metastatic process, which can be further explored.

A guide for the generation of repositories of clinical samples for research on Chagas disease.

Chagas disease, caused by the parasite Trypanosoma cruzi, affects over 6 million people, mainly in Latin America. Two different clinical phases, acute and chronic, are recognised. Currently, 2 anti-parasitic drugs are available to treat the disease (nifurtimox and benznidazole), but diagnostic methods require of a relatively complex infrastructure and trained personnel, limiting its widespread use in endemic areas, and the access of patients to treatment. New diagnostic methods, such as rapid tests (RDTs) to diagnose chronic Chagas disease, or loop-mediated isothermal amplification (LAMP), to detect acute infections, represent valuable alternatives, but the parasite's remarkable genetic diversity might make its implementation difficult. Furthermore, determining the efficacy of Chagas disease treatment is complicated, given the slow reversion of serological anti-T. cruzi antibody reactivity, which may even take decades to occur. New biomarkers to evaluate early therapeutic efficacy, as well as diagnostic tests able to detect the wide variety of circulating genotypes, are therefore, urgently required. To carry out studies that address these needs, high-quality and traceable samples from T. cruzi-infected individuals with different geographical backgrounds, along with associated clinical and epidemiological data, are necessary. This work describes the framework for the creation of such repositories, following standardised and uniform protocols, and considering the ethical, technical, and logistic aspects of the process. The manual can be adapted according to the resources of each laboratory, to guarantee that samples are obtained in a reproducible way, favouring the exchange of data among different work groups, and their generalizable evaluation and analysis. The main objective of this is to accelerate the development of new diagnostic methods and the identification of biomarkers for Chagas disease.

Clinical trials for Chagas disease: etiological and pathophysiological treatment.

Chagas disease (CD) is caused by the flagellate protozoan Trypanosoma cruzi. It is endemic in Latin America. Nowadays around 6 million people are affected worldwide, and 75 million are still at risk. CD has two evolutive phases, acute and chronic. The acute phase is mostly asymptomatic, or presenting unspecific symptoms which makes it hard to diagnose. At the chronic phase, patients can stay in the indeterminate form or develop cardiac and/or digestive manifestations. The two trypanocide drugs available for the treatment of CD are benznidazole (BZ) and nifurtimox (NFX), introduced in the clinic more than five decades ago. WHO recommends treatment for patients at the acute phase, at risk of congenital infection, for immunosuppressed patients and children with chronic infection. A high cure rate is seen at the CD acute phase but better treatment schemes still need to be investigated for the chronic phase. There are some limitations within the use of the trypanocide drugs, with side effects occurring in about 40% of the patients, that can lead patients to interrupt treatment. In addition, patients with advanced heart problems should not be treated with BZ. This is a neglected disease, discovered 114 years ago that still has no drug effective for their chronic phase. Multiple social economic and cultural barriers influence CD research. The high cost of the development of new drugs, in addition to the low economical return, results in the lack of investment. More economic support is required from governments and pharmaceutical companies on the development of more research for CD treatment. Two approaches stand out: repositioning and combination of drugs, witch drastically decrease the cost of this process, when compared to the development of a new drug. Here we discuss the progress of the clinical trials for the etiological and pathophysiological treatment for CD. In summary, more studies are needed to propose a new drug for CD. Therefore, BZ is still the best option for CD. The trials in course should clarify more about new treatment regimens, but it is already possible to indicate that dosage and time of treatment need to be adjusted.

Predictors of Trypanosoma cruzi PCR positivity in patients with chronic Chagas disease

BACKGROUND A positive Trypanosoma cruzi polymerase chain reaction (PCR) is associated with a worse prognosis in patients with chronic Chagas disease (CD). OBJECTIVES To study the association of clinical, electrocardiographic, and echocardiographic characteristics and biomarker blood levels with positive T. cruzi PCR in chronic CD. METHODS This is a single-centre observational cross-sectional study. Positive T. cruzi PCR association with clinical, electrocardiographic, and echocardiographic characteristics, and biomarker blood levels were studied by logistic regression analysis. p values < 0.05 were considered significant. FINDINGS Among 333 patients with chronic CD (56.4% men; 62 ± 10 years), T. cruzi PCR was positive in 41.1%. Stepwise multivariate logistic regression showed an independent association between positive T. cruzi PCR and diabetes mellitus {odds ratio (OR) 0.53 [95% confidence interval (CI) 0.30-0.93]; p = 0.03}, right bundle branch block [OR 1.78 (95% CI 1.09-2.89); p = 0.02], and history of trypanocidal treatment [OR 0.13 (95% CI 0.04-0.38); p = 0.0002]. Among patients with a history of trypanocidal treatment (n = 39), only four (10%) patients had a positive T. cruzi PCR. MAIN CONCLUSIONS Among several studied parameters, only diabetes mellitus, right bundle branch block, and history of trypanocidal treatment showed an independent association with positive T. cruzi PCR. History of trypanocidal treatment was a strong protective factor against a positive T. cruzi PCR.

Translational research in Chagas disease: perspectives in nutritional therapy emerging from selenium supplementation studies as a complementary treatment

Translational research (TR) is an interdisciplinary branch of the biomedical field that seeks to connect its three supporting pillars: basic research on the bench, the hospital beds and other health system services, and the delivery of products for the well-being and health of the community. Here, we review the five transition stages of the TR spectrum, registering the lessons learned during > 20 years leading to the first clinical trial designed and performed in Brazil for testing a complementary treatment for Chagas disease (CD): the selenium trial (STCC). Lessons learned were: (1) to consider all the TR spectrum since the beginning of the project; (2) to start simultaneously animal studies and translation to humans; (3) to ensure a harmonious interaction between clinical and basic research teams; (4) to include MSc and PhD students only in pre-clinical and basic studies (TR0) or vertical clinical studies using retrospective samples and data (TR1); (5) to identify potential suppliers in the national commercial market for a future final treatment since the pre-clinical stage; (6) to keep an international network of experts as permanent advisers on the project. In the whole process, some perspectives were created: a complementary clinical trial for the opened questions and the construction of a Brazilian clinical CD platform.

Transforming growth factor-ß as a therapeutic target for the cardiac damage of Chagas disease

Transforming growth factor beta (TGF-β) is deeply involved on the pathogenesis of Chagas disease. Our group has been investigating the participation of this pleiotropic cytokine in different aspects of Chagas disease over the last 20 years. Important observations have been made, such as: (i) the ability of Trypanosoma cruzi in activating latent TGF-β; (ii) the potential involvement of TGF-β pathway on T. cruzi invasion of host cells; (iii) association of TGF-β with parasite intracellular replication; (iv) cardiac fibrosis development and maintenance; (v) disruption of Connexin-43 plaque structures and (vi) inflammation and immune response. In this perspective article we intend to discuss the advances of the potential use of new therapies targeting TGF-β to treat the cardiac alterations of Chagas disease-affected patients.

Manejo da sede: perspectiva do paciente cirúrgico queimado / Thirst management: perspective of burnt surgical patient

Objetivo: explorar a percepção de um paciente cirúrgico queimado em relação à sede e seu manejo no período pré-operatório e pós-operatório imediato. Relato de caso: trata-se de um estudo com abordagem qualitativa, exploratória, do tipo estudo de caso. Os critérios de inclusão foram: paciente estar internado no centro de tratamento de queimados, ser submetido a procedimento cirúrgico ou balneoterapia, ter experenciado a sede no período pré-operatório ou pós-operatório e ter recebido o manejo da sede. Para a coleta de dados utilizou-se entrevista semiestruturada, gravada e transcrita. Paciente do sexo feminino, de 32 anos, admitida com queimaduras de segundo grau em extensão de tórax, membros superiores e pescoço por tentativa de autoextermínio com álcool. Passou por seis procedimentos e esteve internada por 15 dias até o momento da coleta. Experienciou o desconforto sede durante o jejum pré-operatório e pós-operatório, considerado intenso e muito estressante durante sua internação. Conclusão: a partir da identificação do desconforto sede, utilizou-se como estratégia o picolé de gelo, que fez diferença em seu tratamento. O modelo de manejo da sede é pioneiro no cuidado ao paciente queimado e apresenta benefícios para minorar a sede.

Objective: explore thirst perception of a burnt surgical patient and its management in the preoperative and immediate postoperative period. Case report: study with a qualitative and exploratory approach, named as case study. Inclusion criteria were: inpatient at burnt treatment unit, undergone surgical procedure or balneotherapy, experienced thirst in the preoperative or postoperative period and received thirst management. For data collection, semi-structured interviews were performed, recorded and transcribed. Female patient, 32 years old, admitted with second degree burns in extension of thorax, upper limbs and neck due to attempted self-extermination with alcohol. Underwent six procedures and was hospitalized for 15 days until the data collection. Experienced thirst discomfort during preoperative and postoperative fasting, which was considered intense and very stressful during his hospitalization. Conclusion: since the identification of thirst discomfort, the ice popsicle was used as a strategy, which made difference in her treatment. The thirst management model is pioneer in care of burnt patients and has benefits to alleviate thirst.

Increased angiogenesis parallels cardiac tissue remodelling in experimental acute Trypanosoma cruzi infection

BACKGROUND Angiogenesis has been implicated in tissue injury in several noninfectious diseases, but its role in Chagas disease (CD) physiopathology is unclear. OBJECTIVES The present study aimed to investigate the effect of Trypanosoma cruzi infection on cardiac angiogenesis during the acute phase of experimental CD. METHODS The signalling pathway involved in blood vessel formation and cardiac remodelling was evaluated in Swiss Webster mice infected with the Y strain of T. cruzi. The levels of molecules involved in the regulation of angiogenesis, such as vascular endothelial growth factor-A (VEGF-A), Flk-1, phosphorylated extracellular-signal-regulated protein kinase (pERK), hypoxia-inducible factor-1α (HIF-1α), CD31, α-smooth muscle actin (α-SMA) and also the blood vessel growth were analysed during T. cruzi infection. Hearts were analysed using conventional histopathology, immunohistochemistry and western blotting. FINDINGS In this study, our data demonstrate that T. cruzi acute infection in mice induces exacerbated angiogenesis in the heart and parallels cardiac remodelling. In comparison with noninfected controls, the cardiac tissue of T. cruzi-infected mice presented higher levels of (i) HIF-1α, VEGF-A, Flk-1 and pERK; (ii) angiogenesis; (iii) α-SMA+ cells in the tissue; and (iv) collagen -1 deposition around blood vessels and infiltrating throughout the myocardium. MAIN CONCLUSIONS We observed cardiac angiogenesis during acute experimental T. cruzi infection parallels cardiac inflammation and remodelling.

Outcomes associated with Hydroxychloroquine and Ivermectin in hospitalized patients with COVID-19: a single-center experience

SUMMARY OBJECTIVE: Hydroxychloroquine and Ivermectin are advocated as potential treatments for coronavirus disease 2019 (COVID-19) despite the lack of supportive clinical evidence. In this study, outcomes associated with Hydroxychloroquine and/or Ivermectin were determined in a series of patients with confirmed COVID-19 from a single institution in Brazil. METHODS: Consecutive patients admitted between March and July 2020 were retrospectively analyzed and divided into four treatment categories: no treatment (Group 0), Ivermectin only (Group I), Hydroxychloroquine only (Group II), and Hydroxychloroquine and Ivermectin (Group III). Intensive care unit admission, mechanical ventilation, and death were compared between the Groups. RESULTS: A total of 230 patients were included, with the following treatment distribution: 35.2% (0), 9.1% (I), 48.3% (II), and 7.4% (III). Groups I, II, and III had the higher rates of Intensive care unit admission, mechanical ventilation, or death (0: 23.5% versus I: 38.1% versus II: 37.8% versus III: 70.6%, p=0.002), and the greatest mortality was found in Group III (0 versus III: 13.6% versus 35.3%, p=0.03). In the multivariate analysis, Hydroxychloroquine remained significantly associated with death (OR 3.3, 95%CI 1.1-9.6, p=0.03). CONCLUSION: In a series of consecutive hospitalized patients with COVID-19, Ivermectin was not associated with improved outcomes and Hydroxychloroquine may have resulted in a harmful effect.

Registro Multicêntrico de Takotsubo (REMUTA) - Aspectos Clínicos, Desfechos Intra-Hospitalares e Mortalidade a Longo Prazo / Takotsubo Multicenter Registry (REMUTA) - Clinical Aspects, In-Hospital Outcomes, and Long-Term Mortality

Resumo Fundamento A síndrome de takotsubo (takotsubo) é uma forma de cardiomiopatia adquirida. Dados nacionais sobre essa condição são escassos. O Registro REMUTA é o primeiro a incluir dados multicêntricos dessa condição no nosso país. Objetivo Descrever as características clínicas, prognóstico, tratamento intra-hospitalar e mortalidade hospitalar e em 1 ano de seguimento. Métodos Estudo observacional, retrospectivo, tipo registro. Incluídos pacientes internados com diagnóstico de takotsubo ou que desenvolveram esta condição durante internação por outra causa. Os desfechos avaliados incluíram fator desencadeador, análise dos exames, uso de medicações, complicações e óbito intra-hospitalar e em 1 ano de seguimento. O nível de significância adotado foi de 5%. Resultados Foram incluídos 169 pacientes, em 12 centros no Estado do Rio de Janeiro. A idade média foi de 70,9 ± 14,1 anos e 90,5% eram do sexo feminino; 63% dos casos foram de takotsubo primário e 37% secundário. Troponina I foi positiva em 92,5% dos pacientes e a mediana de BNP foi de 395 (176,5; 1725). Supradesnivelamento do segmento ST esteve presente em 28% dos pacientes. A fração de ejeção do ventrículo esquerdo teve mediana de 40 (35; 48)%. Observamos taxa de 25,7% de ventilação mecânica invasiva e 17,4% de choque. Suporte circulatório mecânico foi utilizado em 7,7%. A mortalidade intra-hospitalar foi de 10,6% e a mortalidade ao final de 1 ano foi de 16,5%. Takotsubo secundário e choque cardiogênico foram preditores independentes de mortalidade. Conclusão Os resultados do REMUTA mostram que takotsubo não se trata de patologia benigna como se pensava, especialmente no grupo de takotsubo secundário que acarreta elevada taxa de complicações e de mortalidade. (Arq Bras Cardiol. 2020; 115(2):207-216)

Abstract Background Takotsubo syndrome (TTS) is an acquired form of cardiomyopathy. National Brazilian data on this condition are scarce. The Takotsubo Multicenter Registry (REMUTA) is the first to include multicenter data on this condition in Brazil. Objective To describe the clinical characteristics, prognosis, in-hospital treatment, in-hospital mortality, and mortality during 1 year of follow-up. Methods This is an observational, retrospective registry study including patients admitted to the hospital with diagnosis of TTS and patients admitted for other reasons who developed this condition. Evaluated outcomes included triggering factor, analysis of exams, use of medications, complications, in-hospital mortality, and mortality during 1 year of follow-up. A significance level of 5% was adopted. Results The registry included 169 patients from 12 centers in the state of Rio de Janeiro, Brazil. Mean age was 70.9 ± 14.1 years, and 90.5% of patients were female; 63% of cases were primary TTS, and 37% were secondary. Troponin I was positive in 92.5% of patients, and median BNP was 395 (176.5; 1725). ST-segment elevation was present in 28% of patients. Median left ventricular ejection fraction was 40 (35; 48)%. We observed invasive mechanical ventilation in 25.7% of cases and shock in 17.4%. Mechanical circulatory support was used in 7.7%. In-hospital mortality was 10.6%, and mortality at 1 year of follow-up was 16.5%. Secondary TTS and cardiogenic shock were independent predictors of mortality. Conclusion The results of the REMUTA show that TTS is not a benign pathology, as was once thought, especially regarding the secondary TTS group, which has a high rate of complications and mortality. (Arq Bras Cardiol. 2020; 115(2):207-216)

Factors that bias teacher expectations: Findings from Chile / Factores que sesgan las expectativas docentes: hallazgos en Chile

Abstract It is well-known that teacher expectations tend to be biased by factors such as student socio-economic status (SES) and gender. However, much less research has been devoted to understanding how teacher characteristics may impact their own expectations of the students. The present study investigated teacher expectations for 343 Chilean teachers (240 in-service and 103 pre-service). We first designed and validated an instrument to measure expectations; then we assessed the effect of teacher gender and experience, and student gender and school-SES in the formation of teacher expectations. The data were analysed using hypothesis and data-driven analyses. The results showed that SES had an effect on teacher expectations (η2= .03 to .12); there was a higher probability that teachers from high-SES schools would have positive expectations of their students. However, negative expectations were equally distributed across teachers working in high and low-SES schools. There was also no evidence of the effect of teacher or student gender on teacher expectations. With respect to teacher experience, the findings were clear cut; both pre-service and in-service teachers shared identical expectations of their students. These findings have important implications regarding teacher training programmes since the expectation bias is observed very early during training.

Resumen Es bien sabido que las expectativas docentes tienden a estar sesgadas por factores como el nivel socioeconómico de los estudiantes (NSE) y el género. Sin embargo, se ha investigado menos cómo las características de los docentes pueden afectar sus propias expectativas de los estudiantes. El presente estudio investigó las expectativas de 343 docentes chilenos (240 en servicio y 103 alumnos en prácticas). Primero se diseñó y validó un instrumento para medir expectativas; luego se evaluó el efecto del género y experiencia del profesor, y el género del estudiante y NSE de la escuela en la formación de las expectativas del profesor. Los datos fueron analizados mediante técnicas dirigidas por hipótesis y por datos. Los resultados mostraron un efecto del NSE de la escuela en las expectativas docentes (η2 = .03 a .12), con una mayor probabilidad de que los profesores de escuelas con alto NSE tengan expectativas positivas de sus estudiantes. Sin embargo, las expectativas negativas fueron distribuidas equitativamente entre los profesores que trabajaban en escuelas con bajo y alto NSE. Tampoco hubo evidencia del efecto de género de los profesores o estudiantes en las expectativas del profesor. Respecto a la experiencia del profesor, los hallazgos son claros; tanto los estudiantes en práctica profesional como los profesores en servicio mostraron idénticas expectativas hacia sus estudiantes. Estos hallazgos tienen implicaciones importantes respecto a los programas de formación docente ya que el sesgo de las expectativas se observa tempranamente desde la formación.