SAEDC: Development of a technological solution for exploratory data analysis and statistics in cytotoxicity.

INTRODUCTION: The intergovernmental organizations Organisation for Economic Co-operation and Development (OECD) and Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) have developed guidelines for the use of in vitro models for toxicological evaluation of chemicals. However, the presence of manual steps and the requirement of multiple tools for data analysis, apart from being costly and time-consuming, can inadvertently introduce errors by researchers. OBJECTIVES: We have developed the SAEDC platform (Technological Solution for Exploratory Data Analysis and Statistics for Cytotoxicity, in Portuguese), which enables analysis of cytotoxicity data from assays following OECD Guideline No. 129. METHODOLOGY: In vitro experimental data were used to compare with the analysis methodology suggested in the Guideline. We analyzed 117 data sets covering chemicals from Category I to Unclassified according to GHS classification. RESULTS: The four-parameters of non-linear regression (4PL) calculated by the SAEDC platform showed no significant differences compared to standard methodology in any of the data sets (p > 0.05). The coefficient of determination (R-squared) also demonstrated not only a good fit of the 4PL model to the data but also significant similarity to values obtained by the conventional methodology. Finally, the SAEDC platform predicted LD50 values for the chemicals from IC50, using the Registry of Cytotoxicity (RC) regression models. CONCLUSION: The comparison with the standard data analysis methodology revealed that SAEDC platform fulfills the requirements for cytotoxicity data analysis, generating reliable and accurate results with fewer steps performed by researchers. The use of SAEDC platform for obtaining toxicity values can reduce analysis time compared to the standard methodology proposed by regulatory agencies. Thus, automation of the analysis using the SAEDC platform has the potential to save time and resources for cytotoxicity researchers and laboratories while generating reliable results.

HLA-G and CD152 Expression Levels Encourage the Use of Umbilical Cord Tissue-Derived Mesenchymal Stromal Cells as an Alternative for Immunosuppressive Therapy.

Mesenchymal stromal cells (MSCs) have been used in immunosuppressive therapy due to their therapeutic effects, with the HLA-G molecule seeming to play a fundamental role. This work evaluated alternative MSC sources to bone marrow (BM), namely, umbilical cord tissue (UC), adipose tissue (AD) and dental pulp tissue (DP), and the influence of interferon-γ (IFN-γ) and hypoxia on the cultivation of these cells for use in immunosuppression therapies. Expression of costimulatory markers CD40, CD80 and CD86 and immunosuppressive molecules CD152 and HLA-G was analyzed. Lymphocyte inhibition assays were also performed. Sequencing of the HLA-G gene from exons 1 to 5 was performed using next-generation sequencing to determine the presence of alleles. UC-derived MSCs (UCMSCs) expressed higher CD152 and HLA-G1 under standard cultivation. UCMSCs and DP-derived MSCs (DPSCs) secreted similar levels of HLA-G5. All MSC sources inhibited the proliferation of peripheral blood mononuclear cells (PBMCs); growth under regular versus hypoxic conditions resulted in similar levels of inhibition. When IFN-γ was added, PBMC growth was inhibited to a lesser extent by UCMSCs. The HLA-G*01:04:01:01 allele appears to generate a more efficient MSC response in inhibiting lymphocyte proliferation. However, the strength of this conclusion was limited by the small sample size. UCMSCs are an excellent alternative to BM in immunosuppressive therapy: they express high concentrations of inhibitory molecules and can be cultivated without stimuli, which minimizes cost.

Alternative Methods as Tools for Obesity Research: In Vitro and In Silico Approaches.

The study of adipogenesis is essential for understanding and treating obesity, a multifactorial problem related to body fat accumulation that leads to several life-threatening diseases, becoming one of the most critical public health problems worldwide. In this review, we propose to provide the highlights of the adipogenesis study based on in vitro differentiation of human mesenchymal stem cells (hMSCs). We list in silico methods, such as molecular docking for identification of molecular targets, and in vitro approaches, from 2D, more straightforward and applied for screening large libraries of substances, to more representative physiological models, such as 3D and bioprinting models. We also describe the development of physiological models based on microfluidic systems applied to investigate adipogenesis in vitro. We intend to identify the main alternative models for adipogenesis evaluation, contributing to the direction of preclinical research in obesity. Future directions indicate the association of in silico and in vitro techniques to bring a clear picture of alternative methods based on adipogenesis as a tool for obesity research.

Oral leukoplakia-epidemiological survey and histochemical analysis of 107 cases in Brazil.

OBJECTIVE: To perform an epidemiological survey comparing the cell proliferative activity of 107 cases of oral leukoplakia with their clinical and histopathological characteristics. MATERIALS AND METHODS: A cross-sectional, observational, and histological-histochemical study. The cases came from the Histopathological Diagnostic Service of UPF/RS and the School of Dentistry of Araçatuba FOA/UNESP/SP (1986-2016). The histopathological sections were stained using the silver staining (AgNOR) technique and the nuclei of 100 epithelial cells selected randomly were recorded to count the number of nucleolar organizer regions (NORs). The mean NORs per lesion were correlated to clinical and histological characteristics using ANOVA, at 5% significance. RESULTS: Most of the cases included men (62.62%), white (64.49%), and with an average age of 53.94 years. The most probable etiological factors were smoking (44.7%) and alcohol consumption (9.85%). The evolution time of most lesions was fast (33.65%), manifesting mainly in the form of plaques (70.37%) and without symptoms (58.88%). They were located mainly in the cheek mucosa (26.62%) and presented white color (66.35%), well-defined edges (59.81%), firm consistency (47.5%), and keratinized surface (49.53%). Etiological factor (p = 0.003), evolution time (p = 0.006), symptoms (p = 0.029), location (p = 0.020), consistency (p = 0.047), histopathological characteristics (p = 0.004), and superficial keratinization (p = 0.001) were statistically significant regarding the mean NORs of the leukoplakias studied. CLINICAL RELEVANCE: Oral leukoplakias caused by alcohol consumption and/or tobacco use, considering an evolution time of fewer than 12 months, asymptomatic, located in the lower lip or tongue, and with a firm consistency and increased superficial keratinization should be treated more aggressively by the clinician to avoid cancerization.

Infusion of Mesenchymal Stem Cells to Treat Graft Versus Host Disease: the Role of HLA-G and the Impact of its Polymorphisms.

Hematopoietic stem-cell transplantation is widely performed for the treatment of hematologic diseases and is increasingly being used for the experimental treatment of various autoimmune diseases. Despite the rapid evolution of this therapy, the mortality rate of patients undergoing this procedure is still high, mainly due to the development of graft versus host disease (GvHD). Even with the administration of immunosuppressive therapy, some patients manifest the chronic form of the disease. For these cases, infusion of mesenchymal stem cells (MSCs) was proposed as a therapeutic strategy, considering the immunosuppressive potential of these cells. This review describes the main results obtained in cell therapy with MSCs for the treatment of GvHD. Despite the encouraging results found, some points differed among the studies. Although the factors that influence the different results are uncertain, some investigators have suggested that variations in immunosuppressive molecules are responsible for these divergences. We highlight the key role of the HLA-G gene in modulating the immune response, and the importance of the polymorphisms and alleles of this gene associated with the outcome of the transplants. We suggest that the HLA-G gene and its polymorphisms be analyzed as a factor in selecting the MSCs to be used in treating GvHD, given its strong immunosuppressive role.

The most relevant chromosomal abnormalities in the north of Rio Grande do Sul, Brazil: 26 years of cytogenetic analysis.

From 1992 to 2018, cytogenetic analyses were successfully performed to explore the chromosomal abnormalities of 729 patients, who utilised a pioneering counselling service in the city of Passo Fundo in the northern part of the Brazilian state of Rio Grande do Sul. This city is characterised by a large conglomerate of private and public hospitals. A classical cytogenetic analysis and G-banding were performed using the patient samples. Although normal karyotypes were observed for 562 of the cases, 167 individuals evidenced chromosomal alterations. Among those, 110 exhibited numerical alterations (65.86%), 41 demonstrated structural modifications (24.55%) and 16 showed both numerical and structural chromosomal changes (9.58%). This study describes the diversity of the chromosomal alterations in this region, which have not been previously examined. After 26 years of study, the findings are discussed herein in a self-critical form.

Evaluation of Cellular Proliferative Activity in Patients with Actinic Cheilitis through Silver-stained Nucleolar Organizer Region Method.

Introduction: Actinic cheilitis (AC) is a lesion potentially malignant that affects the lips after prolonged exposure to solar ultraviolet (UV) radiation. The present study aimed to assess and describe the proliferative cell activity, using silver-stained nucleolar organizer region (AgNOR) quantification proteins, and to investigate the potential associations between AgNORs and the clinical aspects of AC lesions. Materials and methods: Cases diagnosed with AC were selected and reviewed from Center of Histopathological Diagnosis of the Institute of Biological Sciences, Passo Fundo University, Brazil. Clinical data including clinical presentation of the patients affected with AC were collected. The AgNOR techniques were performed in all recovered cases. The different microscopic areas of interest were printed with magnification of *1000, and in each case, 200 epithelial cell nuclei were randomly selected. The mean quantity in each nucleus for NORs was recorded. One-way analysis of variance was used for statistical analysis. Results: A total of 22 cases of AC were diagnosed. The patients were aged between 46 and 75 years (mean age: 55 years). Most of the patients affected were males presenting asymptomatic white plaque lesions in the lower lip. The mean value quantified for AgNORs was 2.4 ± 0.63, ranging between 1.49 and 3.82. No statistically significant difference was observed associating the quantity of AgNORs with the clinical aspects collected from the patients (p > 0.05). Conclusion: The present study reports the lack of association between the proliferative cell activity and the clinical aspects observed in patients affected by AC through the quantification of AgNORs. Clinical significance: Knowing the potential relation between the clinical aspects of AC and the proliferative cell activity quantified by AgNORs could play a significant role toward the early diagnosis of malignant lesions in the clinical practice. Keywords: Actinic cheilitis, Proliferative cell activity, Silver-stained nucleolar organizer regions.

Avaliação da atividade proliferativa celular das lesões bucais causadas pelo uso de próteses totais através da impregnação tecidual pela prata / Proliferative cellular activity evaluation of lesions caused by dentures through tissue silver impregnation

Introdução: As próteses totais visam conservar a função do sistema estomatognático do paciente totalmente edêntulo. Porém, na mucosa bucal podem aparecer manifestações cuja principal causa são as próteses totais mal adaptadas. Objetivo: o presente estudo objetiva investigar a proliferação tecidual das lesões causadas por próteses totais removíveis através do método de impregnação pela prata (AgNOR), com isso facilitando o tratamento e a determinação do prognóstico das lesões a serem estudadas. Metodologia: foram selecionados todos os casos das lesões bucais mais comumente associadas à utilização de próteses totais registradas no Serviço de Diagnóstico Histopatológico do ICB­UPF nos anos de 2012 e 2013, tendo sido encontrados 5 casos de granuloma piogênico, 5 casos de hiperplasia de fundo de sulco, 5 casos de fibroma de irritação e 2 casos de fibroma ossificante periférico. Os cortes histopatológicos das lesões foram impregnados pela prata (método AgNOR), tendo sido obtido, com auxílio do programa Image Tool®, o número de NORs de 100 células de cada caso, resultando numa média de NORs em cada grupo de lesões. Resultados: os resultados obtidos foram tabulados em planilha eletrônica e a comparação do número médio de NORs de cada grupo foi realizado por meio do teste estatístico ANOVA, 5% de significância. Resultados: o grupo das hiperplasias de fundo de sulco mostrou média de 2,41 NORs por núcleo, o grupo dos granulo mas piogênicos mostrou 2,44, o fibroma de irritação 2,22, e o fibroma ossificante periférico mostrou média de 1,89 NORs por núcleo celular, diferindo estatisticamente esta lesão das anteriormente mencionadas (p = 0,002). Conclusão: o fibroma ossificante periférico mostrou ser a lesão causada por prótese total removível com a menor atividade proliferativa celular. Tal estudo precisa ser complementado por futuros estudos clínicos.

Introduction: the total dentures are aimed at preserving the function of the stomatognathic system of the fully edentulous patient. However, in the oral mucosa may appear manifestations whose main cause are the totally unsuitable dentures. Objective: this study aims to investigate the proliferation of tissue lesions caused by removable dentures by impregnation method for silver (AgNOR), thereby facilitating the treatment and determining the prognosis of the lesions to be studied. Methodology: we selected all cases of oral lesions most commonly associated with the use of dentures recorded in Histopathological Diagnostic Service ICB-UPF in the years 2012 and 2013, having been found 5 cases of pyogenic granuloma, 5 cases of hyperplasia, 5 cases of irritation fibroma and 2 cases of peripheral ossifying fibroma. Histopathological lesions cuts were impregnated by silver (AgNOR method), having been obtained with the aid of the program Image Tool®, the number of NOR cells 100 in each case, resulting in an average NORs in every group of lesions. Results: the results were tabulated in a spreadsheet and comparing the average number of NORs of each group was conducted through ANOVA, 5% significance level. Results: The group of hyperplasias showed average of 2.41 NORs per nucleus, the group of pyogenic granulomas showed 2.44, the irritation fibroma 2.22, and peripheral ossifying fibroma showed average of 1.89 NORs for cell nucleus, differing significantly from that of the aforementioned lesions (p = 0.002). Conclusion: the peripheral ossifying fibroma proved the injury caused by removable dentures with lower cell proliferative activity. This study needs to be complemented by future clinical studies.