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1.
Am J Bot ; 111(3): e16305, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38517199

RESUMO

PREMISE: The western North American fern genus Pentagramma (Pteridaceae) is characterized by complex patterns of ploidy variation, an understanding of which is critical to comprehending both the evolutionary processes within the genus and its current diversity. METHODS: We undertook a cytogeographic study across the range of the genus, using a combination of chromosome counts and flow cytometry to infer ploidy level. Bioclimatic variables and elevation were used to compare niches. RESULTS: We found that diploids and tetraploids are common and widespread, and triploids are rare and sporadic; in contrast with genome size inferences in earlier studies, no hexaploids were found. Diploids and tetraploids show different geographic ranges: only tetraploids were found in the northernmost portion of the range (Washington, Oregon, and British Columbia) and only diploids were found in the Sierra Nevada of California. Diploid, triploid, and tetraploid cytotypes were found to co-occur in relatively few localities: in the southern (San Diego County, California) and desert Southwest (Arizona) parts of the range, and along the Pacific Coast of California. CONCLUSIONS: Tetraploids occupy a wider bioclimatic niche than diploids both within P. triangularis and at the genus-wide scale. It is unknown whether the wider niche of tetraploids is due to their expansion upon the diploid niche, if diploids have contracted their niche due to competition or changing abiotic conditions, or if this wider niche occupancy is due to multiple origins of tetraploids.


Assuntos
Gleiquênias , Pteridaceae , Diploide , Tetraploidia , Poliploidia
2.
Biomedicines ; 11(12)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38137514

RESUMO

Cancer stem cells are a subpopulation of tumor cells characterized by their ability to self-renew, induce tumors upon engraftment in animals and exhibit strong resistance to chemotherapy and radiotherapy. These cells exhibit numerous characteristics in common with embryonic stem cells, expressing some of their markers, typically absent in non-pathological adult differentiated cells. The aim of this study was to investigate the potential of conditioned media from cancer stem cells to modulate the fate of Leukemia Inhibitory Factor (LIF)-dependent murine embryonic stem cells (mESCs) as a way to obtain a direct readout of the secretome of cancer cells. A functional assay, "the StemDif sensor test", was developed with two types of cancer stem cells derived from grade IV glioblastoma (adult and pediatric) or from gastric adenocarcinoma. We show that conditioned media from the selection of adult but not pediatric Glioma-Inducing Cells (GICs) maintain mESCs' pluripotency in correlation with LIF secretion and activation of STAT3 protein. In contrast, conditioned media from gastric adenocarcinoma cells display LIF-independent stemness and differentiation activities on mESC. Our test stands out for its user-friendly procedures, affordability and straightforward output, positioning it as a pioneering tool for in-depth exploration of cancer stem cell secretome characteristics.

3.
Rev. méd. Minas Gerais ; 33: e-33102, Jan.-Dez. 2023.
Artigo em Inglês, Português | LILACS | ID: biblio-1552537

RESUMO

INTRODUÇÃO: Apesar da disseminação mundial da COVID-19, os padrões epidemiológicos e clínicos da doença ainda permanecem incertos na faixa etária pediátrica. OBJETIVO: Descrever as características epidemiológicas, clínicas, laboratoriais e radiológicas dos pacientes pediátricos diagnosticados com doença causada pelo SARS-CoV-2, hospitalizados na enfermaria do Hospital Regional João Penido, situado em Juiz de Fora/MG. MÉTODOS: Foi realizado um estudo do tipo coorte, com coleta de dados do período da internação referente a critérios epidemiológicos, clínicos, laboratoriais e radiológicos através de formulário próprio desenvolvido para a pesquisa de pacientes pediátricos hospitalizados no período de 11 de março de 2020 até 11 de março de 2021, que receberam diagnóstico de COVID-19, confirmado por RT-PCR ou por sorologia IgM/IgG. RESULTADOS: Dos pacientes com COVID-19, 49,2% tinham idade até 3 anos, 66,2% eram do sexo masculino e, dentre as comorbidades, doença respiratória crônica foi a de maior prevalência (26,9%). A maioria dos pacientes apresentou quadro clínico respiratório (72,7%). Com relação à gravidade da doença, 38,5% apresentaram doença leve, 23,1% moderada, 23,1% grave e 12,3% crítica. No desfecho, 98,5% tiveram alta hospitalar e apenas 1 paciente, que possuía diversas comorbidades, evoluiu a óbito. CONCLUSÃO: A COVID-19 possui apresentações clínicas, radiológicas e laboratoriais variadas e, não existindo tratamento único ou específico, os casos devem ser analisados e conduzidos de forma individual.


INTRODUCTION: Despite the worldwide dissemination of COVID-19, the epidemiological and clinical patterns of the disease remain uncertain in the pediatric age group. OBJECTIVE: To describe the epidemiological, clinical, laboratory and radiological characteristics of pediatric patients diagnosed with disease caused by SARS-CoV-2, hospitalized in the ward of Hospital Regional João Penido, located in Juiz de Fora, MG. METHODS: A cohort study was carried out, with data collection from the period of hospitalization regarding epidemiological, clinical, laboratory and radiological criteria through a specific form developed for the research of pediatric patients, hospitalized from March 11, 2020 to March 11, 2021, who received a diagnosis of COVID-19, confirmed by RT-PCR or by IgM/IgG serology. RESULTS: Of the patients with COVID-19, 49.2% were aged up to 3 years, 66.2% were male and, among the comorbidities, chronic respiratory disease was the most prevalent (26.9%). Most patients had a clinical respiratory condition (72.7%). Regarding disease severity, 38.5% had mild disease, 23.1% moderate, 23.1% severe and 12.3% critical. In the outcome, 98.5% were discharged from the hospital and only 1 patient, who had several comorbidities, died. CONCLUSION: COVID-19 has varied clinical, radiological and laboratory presentations and, since there is no single or specific treatment, cases must be analyzed and managed individually.


Assuntos
Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , COVID-19/epidemiologia , Enfermeiros Pediátricos
4.
Rev. Costarric. psicol ; 42(2): 241-262, jul.-dic. 2023. graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1559041

RESUMO

Resumen Estudio exploratorio-descriptivo sobre un grupo de profesionales costarricenses en psicología acerca de sus actitudes hacia la aplicación de los principios psicológicos en la práctica odontológica. La muestra fue de 377 psicólogos (activos en el Colegio de Profesionales en Psicología de Costa Rica). A partir del cuestionario original diseñado por Gómez y Gómez (2007), el cual fue construido para estimar la necesidad de conformar programas universitarios que integren la psicología y la odontología, se aplicó una adaptación consistente en una encuesta de 10 preguntas autoadministradas de selección simple, la cual se efectuó en línea a través del sistema QuestionPro®. Se pudo evidenciar que existe una actitud positiva ante el enfoque interdisciplinario entre la Odontología y la Psicología; se demostró que un 74% de la muestra sostiene que los aspectos psicosociales son "Bastante importantes" en el marco de la atención odontológica. A pesar de ello, la mayoría (57%) de las personas consultadas indicó que no ha tenido ocasión de aplicar sus conocimientos y experiencia en psicología al contexto odontológico. Asimismo, un 72% de los participantes considera "Bastante importante" que los profesionales en Odontología reciban capacitación básica en el área psicológica para la prevención o contención de ciertos síntomas que puedan incidir en la salud mental. Por otra parte, el 80% de quienes respondieron la encuesta indicaron que las iniciativas interdisciplinarias de colaboración científica (investigación) y aplicada (ejercicio profesional) son "Bastante importantes" para producir beneficios tangibles en la prestación de servicios integrales a los pacientes y el bienestar del personal sanitario.


Abstract Exploratory-descriptive study on a group of Costa Rican professionals in psychology about their attitudes towards the application of psychological principles in dental practice. The sample consisted of 377 psychologists (active in the Association of Psychology Professionals of Costa Rica). From the original questionnaire designed by Gómez and Gómez (2007), which was built to estimate the need to create university programs that integrate psychology and dentistry, an adaptation consisting of a survey of 10 self-administered questions of simple selection was applied, which was carried out online through the QuestionPro® system. It was possible to show that there is a positive attitude towards the interdisciplinary approach between Dentistry and Psychology; it was shown that 74% of the sample maintains that psychosocial aspects are "Quite important" in the context of dental care. Despite this, the majority (57%) of the people consulted indicated that they had not had the opportunity to apply their knowledge and experience as psychologists to the dental context. Likewise, 72% of the participants consider it "Quite important" that dental professionals receive basic training in the psychological area for the prevention or containment of certain symptoms that may affect mental health. On the other hand, 80% of the survey respondents indicated that interdisciplinary initiatives of professional scientific (research) and applied (practice) collaboration are "Quite important" to produce tangible benefits in the provision of comprehensive services to patients and wellbeing of health personnel.


Assuntos
Humanos , Masculino , Feminino , Psicologia , Atitude , Assistência Odontológica/psicologia , Costa Rica , Práticas Interdisciplinares
5.
Front Plant Sci ; 14: 1148828, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152130

RESUMO

Introduction: The high frequency of polyploidy in the evolutionary history of many plant groups occurring in the Mediterranean region is likely a consequence of its dynamic paleogeographic and climatic history. Polyploids frequently have distinct characteristics that allow them to overcome the minority cytotype exclusion. Such traits may enable polyploid individuals to grow in habitats different from their parentals and/or expand to new areas, leading to spatial segregation. Therefore, the successful establishment of polyploid lineages has long been associated with niche divergence or niche partitioning and the ability of polyploids to cope with different, often more stressful, conditions. In this study, we aimed to explore the role of environmental variables associated with the current distribution patterns of cytotypes within the polyploid complex Linum suffruticosum s.l.. Methods: The distribution and environmental niches of the five main cytotypes of Linum suffruticosum s.l. (diploids, tetraploids, hexaploids, octoploids and decaploids) were studied across its distribution range. Realized environmental niche of each cytotype was determined using niche modelling tools, such as maximum entropy modelling and niche equivalency and similarity tests. Results: Differences in the environmental conditions of L. suffruticosum s.l. cytotypes were observed, with polyploids being associated with habitats of increased drought and soil pH, narrower temperature ranges and decreased soil water and cation exchange capacities. Diploids present the widest environmental niche, and polyploids occupy part of the diploid niche. Although some polyploids have equivalent potential ecological niches, cytotypes do not co-occur in nature. Additionally, the ecological niche of this polyploid complex is different between continents, with North African habitats being characterised by differences in soil texture, higher pH, and low cation exchange capacity, precipitation and soil water capacity and higher temperatures than habitats in southwest Europe. Discussion: The different ecological conditions played a role in the distribution of cytotypes, but the mosaic distribution could not be entirely explained by the environmental variables included in this study. Other factors, such as reproductive isolation and competitive interactions among cytotypes, could further explain the current diversity and distribution patterns in white flax. This study provides relevant data on the niche requirements of each cytotype for further competition and reciprocal transplant experiments. further competition and reciprocal transplant experiments.

6.
Front Plant Sci ; 14: 1144678, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909429

RESUMO

Polyploidy has important ecological effects, including ploidy-mediated effects on morphology, breeding system and ecological tolerances. However, there is still little comprehensive research available to test its adaptive significance and its role in driving distributional patterns. This work aimed to assess the contribution of genome duplications to ecological divergence using an experimental approach with the diploid-tetraploid Jasione maritima polyploid complex. We explored if individuals with different ploidy differ in their tolerance to water deficit and if this may contribute to explaining the distribution patterns along a latitudinal gradient in the northwest Iberian Peninsula. For that, we used three cytogenetic entities: diploids and established tetraploids collected in natural populations along a latitudinal gradient, and neotetraploids synthesized from diploid populations after treatments with colchicine. Thirty plants from each of the nine populations were grown under controlled conditions with half randomly assigned to the water deficit treatment, and half used as control. We determined experimental plants' response by measuring fitness-related parameters, such as above and belowground biomass, plant water status, photosynthetic efficiency and pigments, membrane stability, antioxidant capacity and sugars content. Our data shows that biomass, chlorophyll content, photochemical quenching (qP) and non-photochemical quenching (NPQ) in neotetraploids and established tetraploids were significantly higher than in diploids and that these differences could be attributed to genome duplications. In response to the water deficit, diploids seem to use a strategy of avoidance, whereas tetraploids seem to employ the strategy of tolerance to overcome water deficit stress, which appears equally efficient. Additionally, we did not observe a response pattern along the latitudinal gradient of the distributional range of the J. maritima complex. The results indicate that the response to water deficit is population dependent. Further studies are necessary to understand the role of ploidy in explaining the distribution patterns of the J. maritima complex.

7.
Front Oncol ; 13: 1072802, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36874142

RESUMO

Introduction: Helicobacter pylori colonizes the gastric mucosa and induces chronic inflammation. Methods: Using a mouse model of H. pylori-induced gastritis, we evaluated the mRNA and protein expression levels of proinflammatory and proangiogenic factors, as well as the histopathological changes in gastric mucosa in response to infection. Five- to six-week-old female C57BL/6N mice were challenged with H. pylori SS1 strain. Animals were euthanized after 5-, 10-, 20-, 30-, 40- and 50-weeks post infection. mRNA and protein expression of Angpt1, Angpt2, VegfA, Tnf-α, bacterial colonization, inflammatory response and gastric lesions were evaluated. Results: A robust bacterial colonization was observed in 30 to 50 weeks-infected mice, which was accompanied by immune cell infiltration in the gastric mucosa. Compared to non-infected animals, H. pylori-colonized animals showed an upregulation in the expression of Tnf-A, Angpt2 and VegfA at the mRNA and protein levels. In contrast, Angpt1 mRNA and protein expression was downregulated in H. pylori-colonized mice. Conclusion: Our data show that H. pylori infection induces the expression of Angpt2, Tnf-A and Vegf-A in murine gastric epithelium. This may contribute to the pathogenesis of H. pylori-associated gastritis, however the significance of this should be further addressed.

8.
Ann Bot ; 131(1): 171-184, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35390125

RESUMO

BACKGROUND AND AIMS: Hybridization is a common and important force in plant evolution. One of its outcomes is introgression - the transfer of small genomic regions from one taxon to another by hybridization and repeated backcrossing. This process is believed to be common in glacial refugia, where range expansions and contractions can lead to cycles of sympatry and isolation, creating conditions for extensive hybridization and introgression. Polyploidization is another genome-wide process with a major influence on plant evolution. Both hybridization and polyploidization can have complex effects on plant evolution. However, these effects are often difficult to understand in recently evolved species complexes. METHODS: We combined flow cytometry, analyses of transcriptomic sequences and pollen tube growth assays to investigate the consequences of polyploidization, hybridization and introgression on the recent evolution of several Erysimum (Brassicaceae) species from the South of the Iberian Peninsula, a well-known glacial refugium. This species complex differentiated in the last 2 million years, and its evolution has been hypothesized to be determined mainly by polyploidization, interspecific hybridization and introgression. KEY RESULTS: Our results support a scenario of widespread hybridization involving both extant and 'ghost' taxa. Several taxa studied here, most notably those with purple corollas, are polyploids, probably of allopolyploid origin. Moreover, hybridization in this group might be an ongoing phenomenon, as pre-zygotic barriers appeared weak in many cases. CONCLUSIONS: The evolution of Erysimum spp. has been determined by hybridization to a large extent. Species with purple (polyploids) and yellow flowers (mostly diploid) exhibit a strong signature of introgression in their genomes, indicating that hybridization occurred regardless of colour and across ploidy levels. Although the adaptive value of such genomic exchanges remains unclear, our results demonstrate the significance of hybridization for plant diversification, which should be taken into account when studying plant evolution.


Assuntos
Brassicaceae , Erysimum , Hibridização Genética , Poliploidia , Europa (Continente) , Filogenia
9.
Poblac. salud mesoam ; 19(2)jun. 2022.
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1386956

RESUMO

Abstract The aim of this work is to describe and analyze the association of PGI/PGII ratio (indicator of gastric atrophy) with H. pylori-CagA and life style factors such as caloric intake, obesity, and harmful habits amongst H. pylori-positive elderly people infected in Costa Rica using an exploratory multigroup structural equations model (SEM). Using a sample of 1748 H. pylori-positive elderly people from CRELES first wave study, a SEM was employed analyze if the relationships between PGI/PGII ratio with levels of H. pylori-CagA, caloric intake, obesity, and harmful habits, differs by sex, age and risk areas subgroups. The proposed SEMs exhibited a good fit in males (RMSEA = 0.039), females (RMSEA = 0.000), low-risk area (RMSEA = 0.038), middle-risk area (RMSEA = 0.042), individuals under 80 years (RMSEA = 0.038) and individuals aged 80 and over (RMSEA = 0.042), while an acceptable fit was observed for the high-risk area (RMSEA = 0.061). Fitted SEMs showed that CagA predicted PG-ratio as expected, with effects increasing with the risk area, but similar between sex and age groups. All indicators measuring obesity (BMI, arms, and waist) showed significant standardized coefficients, with similar effects between sex, age and risk area groups. No other significant effects or differences between groups were identified. We propose a good-fitted SEM model for the possible relationships between CagA and PG ratio and the geographical risk area level for elderly people. No differences were observed on measured parameters between male and female population, or between under 80 years and older individuals.


Resumen El objetivo de este trabajo es describir y analizar la asociación entre PGI/PGII (indicador de atrofia gástrica con H. pylori-CagA y factores asociados a estilo de vida como ingesta calórica, obesidad y hábitos nocivos entre adultos mayores positivos por H. pylori en Costa Rica utilizando modelos de ecuaciones estructurales multigrupo (SEM). Con una muestra de 1748 adultos mayores del estudio CRELES, se utilizó un SEM para analizar las relaciones entre PGI/PGII, CagA, ingesta calórica, obesidad y hábitos nocivos difieren por sexo, edad y áreas de riesgo. Los SEMs propuestos exhibieron un buen ajuste en hombres (RMSEA = 0.039), mujeres (RMSEA = 0.000), área de bajo riesgo (RMSEA = 0.038), áreas de riesgo medio (RMSEA = 0.042), individuos menores de 80 años (RMSEA = 0.038) e individuos de 80 años o más (RMSEA = 0.042), mientras que hubo un ajuste aceptable en áreas de alto riesgo (RMSEA = 0.061). Los SEMs ajustados mostraron que CagA predice la relación PGI/II en la dirección esperada con efectos proporcionales al área de riesgo, pero no por sexo y edad. Todos los indicadores medibles de obesidad (IMC, brazos y cintura) mostraron coeficientes estandarizados significativos con efectos similares entre los grupos por sexo, edad y área de riesgo. No se encontraron otros efectos o diferencias significativas. Proponemos un modelo SEM bien ajustado para las posibles relaciones entre CagA y PGI/II y el nivel de riesgo del área geográfica en adultos mayores. No se encontraron diferencias en las variables analizadas entre hombres y mujeres ni entre los grupos de edad.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Helicobacter pylori , Ingestão de Energia , Gastrite Atrófica , Obesidade
10.
Acta med. costarric ; 64(2)jun. 2022.
Artigo em Espanhol | SaludCR, LILACS | ID: biblio-1419884

RESUMO

Objetivo: Determinar la viabilidad del cultivo de la bacteria Helicobacter pylori en Costa Rica por medio de la documentación de toma de muestras, la comparación del diagnóstico histopatológico y la descripción de los diagnósticos asociados a los aislamientos obtenidos con los resultados de la ureasa rápida. Métodos: Investigación descriptiva que involucró a pacientes de entre los 35 y 70 años, de ambos sexos, que asistieron al Servicio de Endoscopia Digestiva del Hospital Clínica Bíblica entre febrero y junio del 2019 para estudio gastroscópico. Se obtuvieron biopsias gástricas para diagnóstico histopatológico, prueba de ureasa rápida y cultivo de Helicobacter pylori. Para este último, se transportaron las biopsias en un medio de transporte semisólido, se maceró el tejido y se cultivó enagar Skirrow y agar selectivo para Helicobacter; una placa de cada medio se incubó a 37 °C en microaerofilia entre 48 horas y 10 días. La positividad del cultivo se realizó por observación de la morfología colonial y la bacteria se identificó por análisis microscópico al fresco, tinción de Gram y pruebas bioquímicas (catalasa, ureasa y oxidasa). Resultados: Se incluyó a 44 pacientes (edad: 50.6 ± 10.0, 54.5% masculinos). Se recuperó Helicobacter pylori en biopsias de 27 pacientes (61.4% de éxito). La recuperación de la bacteria fue similar en el medio Skirrow y en el selectivo para Helicobacter. El porcentaje de éxito de recuperación semanal aumentó durante el estudio hasta alcanzar un éxito del 100% en la semana 11. Se comparó el cultivo con la ureasa rápida en 27 pacientes y la concordancia entre ambos métodos fue de un coeficiente kappa de Cohen de 0.48. El cultivo detectó la bacteria en un 56% de los pacientes, la ureasa rápida en un 37% y la combinación de ambas técnicas permitió la detección en un 60%. El diagnóstico endoscópico más frecuente en los pacientes con cultivo positivo fue la gastritis eritematosa y gastritis crónica superficial y el diagnóstico histopatológico predominante fue gastritis crónica con atrofia gástrica. El diagnóstico por cultivo coincidió con la detección por azul de toluidina en un 80.4% de los casos. Conclusiones: Se puede implementar el cultivo de Helicobacter pylori en Costa Rica. Este estudio tuvo un porcentaje de recuperación de la bacteria de 61.4%. La combinación del método de cultivo con la prueba de ureasa rápida y la detección histológica contribuye a un diagnóstico certero y oportuno. Recomendamos que, con base en protocolos descritos en esta investigación, cada laboratorio estandarice las condiciones que le permitan un buen porcentaje de recuperación y una implementación adaptada a sus actividades de rutina.


Aim: To document the recent experiences on the implementation of sampling and culturing Helicobacter pylori in Costa Rica, to compare it with other diagnostic methods: rapid urease test and histopathology and to describe the diagnoses associated with the obtained isolates. Methods: Descriptive research involving patients who visited the digestive endoscopy department of the Clínica Bíblica hospital in San José, Costa Rica between February and July of 2019 for gastroscopy. Gastric biopsies were obtained and histopathological analysis, rapid urease test, and bacteriological culture for Helicobacter pylori were performed. For culture techniques, the sample was transported in an in-house semi-solid medium. Biopsy fragments were macerated and plated on Skirrow agar and Helicobacterselective in-house agar, and incubated in microaerophilic atmosphere for 48 hours to 10 days. Culture positivity was determined by observation of the colonial morphology and microscopic observation; Gram staining and biochemical tests (urease, catalase, and oxidase) were used for bacterial identification. Results: 44 patients (mean aged 50.6 ± 10.0 years old, 54.5% male) were included in the study. Helicobacter pylori was recovered in biopsies from 27 patients (61.4% success rate). Bacterial growth was similar regardless the culture medium, but the physiological state of the bacteria was better in the Helicobacter-selective agar than in Skirrow. The weekly recovery rate increased to reach a 100% recovery plateau on week 11. Culture was compared with the rapid urease test in 27 patients, and the concordance between both methods using Cohen's kappa coefficient was 0.48. Whilst the culture detected Helicobacter pylori in 56% of the patients, and the rapid urease test in 37%, the combination of both allowed a 60% rate. The most frequent endoscopic diagnosis in patients with positive cultures were erythematous gastritis and chronic superficial gastritis, and the predominant histopathological diagnosis was chronic atrophic gastritis. Culture-based diagnosis was consistent with the histopathology detection of Helicobacter pylori in 80.4% of the cases. Conclusions: The implementation of H. pylori culture in Costa Rica is possible. This study had a 61.4% recovery rate. The combination of culture with rapid urease test and histopathology increases the probability of an accurate and timely diagnosis. We recommend that, based on previously described protocols such as ours, each laboratory adjusts the conditions to allow a good recovery rate and implement H. pylori diagnostic methods most suitable to their routine activities.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Neoplasias Gástricas/diagnóstico , Bacteriologia , Helicobacter pylori/isolamento & purificação , Costa Rica
11.
Genes (Basel) ; 12(6)2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208200

RESUMO

Polyploidy has played an important evolutionary role in the genus Festuca (Poaceae), and several ploidy levels (ranging from 2n = 2x = 14 to 2n = 12x = 84) have been detected to date. This study aimed to estimate the genome size and ploidy level of two subspecies belonging to the F. yvesii polyploid complex by flow cytometry and chromosome counting. The phenotypic variation of the cytotypes was also explored, based on herbarium material. The genome size of F. yvesii subsp. lagascae has been estimated for the first time. Nuclear 2C DNA content of F. yvesii subsp. summilusitana ranged from 21.44 to 31.91 pg, while that of F. yvesii subsp. lagascae was from 13.60 to 22.31 pg. We report the highest ploidy level detected for Festuca (2n = 14x = 98) and previously unknown cytotypes. A positive correlation between holoploid genome size and chromosome number counts shown herein was confirmed. The morphometric approach showed a slight trend towards an increase in the size of some organs consistent with the variation in the ploidy level. Differences in characters were usually significant only among the most extreme cytotypes of each subspecies, but, even in this case, the high overlapping ranges prevent their distinction.


Assuntos
Festuca/genética , Tamanho do Genoma , Polimorfismo Genético , Poliploidia , Cromossomos de Plantas/genética
12.
Am J Med Sci ; 362(2): 182-187, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34088492

RESUMO

BACKGROUND: Costa Rica is ranked as one of the countries with highest incidence of gastric cancer worldwide. Previous studies in Costa Rican populations have revealed associations between gastric cancer risk and several cytokine polymorphisms that seem to play a role in the regulation of the expression of these proteins. In this study, we assessed associations of the polymorphisms IL-6-174 G/C, IFNGR1-56 C/T, IL-8-251 T/A and TNF-A (-857 C/T, -308 A/G) with gastric pathologies in a high-risk population of Latin America. METHODS: DNA samples of 47 patients with gastric adenocarcinoma, 53 with chronic gastritis, 56 with duodenal ulcer and 94 healthy controls, were genotyped for the five mentioned SNPs. All participants were ≥50-years-old. Genotyping was performed by PCR-RFLP and 5'-nuclease PCR assay. H. pylori infection, CagA status, pepsinogen (PG) I and II blood levels were determined by ELISA. Logistic regression analysis was used to determine possible associations of the polymorphisms with cancer, gastritis and duodenal ulcer, and linear regression analysis to determine associations with blood PG levels. RESULTS: A total of 86.6% of the population was positive for H. pylori; of them, 51.6% was CagA+. Patients with the TNF-A-857*T allele had an increased risk for gastritis (OR: 3.67, p = 0.015) and gastric adenocarcinoma (OR:6.15, p = 0.001). Associations between other polymorphisms and gastric diseases, or PG levels, were not found. CONCLUSIONS: Our results indicate that the TNF-A-857*T SNP is among the risk factors associated with the risk of gastric cancer in Costa Rica.


Assuntos
Adenocarcinoma/genética , Biomarcadores Tumorais/genética , Neoplasias Gástricas/genética , Fator de Necrose Tumoral alfa/genética , Adenocarcinoma/epidemiologia , Idoso , Costa Rica/epidemiologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Neoplasias Gástricas/epidemiologia
13.
Front Immunol ; 12: 643298, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025655

RESUMO

The immune system plays a key role in the protective response against oral cancer; however, the tumor microenvironment (TME) impairs this anti-cancer response by modulating T helper (Th) responses and promoting an anti-inflammatory environment. Regulatory T cells (Tregs) and Th2 effector cells (Teff) are associated with poor prognosis in oral squamous cell carcinoma (OSCC). However, the main immunomodulatory mechanisms associated with the enrichment of these subsets in OSCC remain unknown. We characterized Th-like lineages in Tregs and Teff and evaluated immunomodulatory changes induced by the TME in OSCC. Our phenotypic data revealed a higher distribution of tumour-infiltrating CCR8+ and Th2-like Treg in OSCC compared with non-malignant samples, whereas the percentages of Th1 cells were reduced in cancer. We then analyzed the direct effect of the TME by exposing T cell subsets to cancer secretomes and observed the OSCC secretome induced CCR8 expression and reduced cytokine production from both subsets. Transcriptomic analysis showed that the co-culture with OSCC secretome induced several gene changes associated with the vitamin D (VitD) signaling pathway in T cells. In addition, proteomic analysis identified the presence of several proteins associated with prostaglandin E2 (PGE2) production by rapid membrane VitD signaling and a reduced presence of the VitD binding protein. Thus, we analyzed the effect of VitD and PGE2 and observed that VitD promotes a regulatory Th2-like response with CCR8 expression whilst PGE2 also modulated CCR8 but inhibited cytokine production in combination with VitD. Finally, we evaluated the presence of CCR8 ligand in OSCC and observed increased chemokine CCL18, which was also able to upregulate CCR8 in activated Th cells. Overall, our data showed the immunomodulatory changes induced by the TME involving CCR8 expression and regulatory Th2 phenotypes, which are associated with PGE2 mediated VitD signaling pathway and CCL18 expression in OSCC.


Assuntos
Regulação Neoplásica da Expressão Gênica/imunologia , Imunomodulação , Neoplasias Bucais/imunologia , Proteínas de Neoplasias/imunologia , Receptores CCR8/imunologia , Transdução de Sinais/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Linfócitos T Reguladores/imunologia , Células Th2/imunologia , Microambiente Tumoral/imunologia , Vitamina D/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Linfócitos T Reguladores/patologia , Células Th2/patologia
14.
Chem Sci ; 13(1): 59-67, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35059151

RESUMO

Catalysis-based approaches for the activation of anticancer agents hold considerable promise. These principally rely on the use of metal catalysts capable of deprotecting inactive precursors of organic drugs or transforming key biomolecules available in the cellular environment. Nevertheless, the efficiency of most of the schemes described so far is rather low, limiting the benefits of catalytic amplification as strategy for controlling the therapeutic effects of anticancer compounds. In the work presented here, we show that flavin reactivity within a hydrogel matrix provides a viable solution for the efficient catalytic activation and delivery of cisplatin, a worldwide clinically-approved inorganic chemotherapy agent. This is achieved by ionically adsorbing a flavin catalyst and a Pt(iv) prodrug as substrate into porous amino-functionalized agarose beads. The hydrogel chassis supplies high local concentrations of electron donating groups/molecules in the surrounding of the catalyst, ultimately boosting substrate conversion rates (TOF >200 min-1) and enabling controlled liberation of the drug by light or chemical stimuli. Overall, this approach can afford platforms for the efficient delivery of platinum drugs as demonstrated herein by using a transdermal diffusion model simulating the human skin.

15.
Mol Phylogenet Evol ; 155: 107006, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33160038

RESUMO

The Balkan Peninsula is recognized as one of the hotspots of biodiversity in Europe. This area has shown since the Last Glacial Maximum appropriate conditions for species diversification and hybridization, which has led to the existence of numerous taxonomically unresolved entities. Here, we focus on the Western Balkans and explore the genetic structure and relationships among species belonging to the V. austriaca - V. orbiculata diploid-polyploid complex, including populations showing intermediate morphologies. A combination of nuclear markers (microsatellites), plastid DNA regions (trnH-psbA, ycf6-psbM) and ploidy level estimations using flow cytometry are employed to assess the genetic structure and evolutionary dynamics of this polyploid complex. To reconstruct the evolutionary history, an approximate Bayesian computation approach is combined with projections of the species distribution models onto the climatic scenarios of the Mid-Holocene (6 ka BP) and Last Glacial Maximum (22 ka BP). Four main groups were found: one well-established entity within the diploid level, V. dalmatica, a second diploid-tetraploid group which corresponds to V. orbiculata, a hexaploid cluster harboring V. austriaca subsp. jacquinii individuals, and an enigmatic tetraploid group. According to the molecular data obtained, this latter cluster represents an allopolyploid cryptic lineage −with V. orbiculata and V. dalmatica as putative parents− morphologically similar to V. orbiculata, but genetically more related to V. austriaca subsp. jacquinii. Veronica dalmatica and this "uncertain tetraploid" group are involved in the formation of the hexaploid taxon V. austriaca subsp. jacquinii, with the possibility of recent gene flow among different cytotypes. The present study supports a scenario of diversification from a diploid common ancestor leading to two different but interrelated lineages. The first one would correspond with the diploid V. orbiculata plus tetraploid individuals of this species arising through allo- and autopolyploidization, and the second one would involve all ploidy levels with allopolyploidization being prevalent.


Assuntos
Biodiversidade , Poliploidia , Alelos , Península Balcânica , Teorema de Bayes , DNA de Cloroplastos/genética , Diploide , Análise Discriminante , Variação Genética , Genética Populacional , Geografia , Humanos , Hibridização Genética , Repetições de Microssatélites/genética , Modelos Teóricos , Filogenia , Plastídeos/genética , Análise de Componente Principal , Veronica/genética
16.
Rev. méd. Minas Gerais ; 31: 31112, 2021.
Artigo em Inglês, Português | LILACS | ID: biblio-1354570

RESUMO

Introdução: de destaque como agente etiológico em várias doenças respiratórias, os vírus, tem grande importância dentro da Pneumologia Pediátrica. Objetivo: estudar os vírus identificados de secreções respiratórias de pacientes pediátricos, hospitalizados na enfermaria e UTI pediátrica, durante o período de janeiro de 2019 a dezembro de 2020. Metodologia: levantamento de resultados do RT-PCR (reação da transcriptase reversa seguida pela reação em cadeia da polimerase) de secreções respiratórias de pacientes pediátricos, através do GAL (Gerenciamento de Análises Laboratoriais) aplicando os filtros necessários para selecionar os pacientes da instituição e o período estipulado. Resultados: Foram realizadas 30 coletas em 2019 e 196 em 2020 de secreções respiratórias devido ao quadro de Síndrome Respiratória. As amostras coletadas em 2019 foram positivas para vírus em 56,7% dos casos investigados, sendo 6,7% para Influenza e 50% para Vírus Sincicial Respiratório (VSR), enquanto que em 2020 as amostras foram positivas em 21,4% dos casos, sendo todos eles para SARS-CoV-2. O período do ano com maior número de coletas de secreção foi em maio e junho considerando o ano de 2019 (60% das coletas de 2019), e julho, agosto e dezembro considerando o ano de 2020 (42,8% das coletas de 2020), com uma positividade de 77,7% (2019) e 25% (2020) para os vírus solicitados para pesquisa. Conclusão: Pôde-se perceber uma importante mudança no perfil dos vírus identificados dos quadros respiratórios entre 2019 e 2020, comparáveis ao perfil apresentado pelos Boletins Epidemiológicos do Ministério da Saúde, principalmente no ano de 2020 com o surgimento do novo coronavírus e sua pandemia. A etiologia viral presente na grande maioria dos quadros respiratórios da pediatria, deve sempre ser valorizada e os testes de identificação viral são ferramentas de grande aplicabilidade na clínica.


Introduction: highlighted as an etiological agent in several respiratory diseases, viruses, has great importance in Pediatric Pulmonology. Objective: study the viruses identified from respiratory secretions of pediatric patients hospitalized in the pediatric ward and ICU, during the period from January 2019 to December 2020. Methodology: survey of results of the RT-PCR (reverse transcriptase reaction followed by polymerase chain reaction) of respiratory secretions of pediatric patients, through the LAM (Laboratory Analysis Management) applying the necessary filters to select the patients of the institution and the stipulated period. Results: Thirty collections were performed in 2019 and 196 in 2020 for respiratory secretions due to the Respiratory Syndrome. The samples collected in 2019 were positive for viruses in 56.7% of the investigated cases, with 6.7% for Influenza and 50% for Respiratory Syncytial Virus (RSV), while in 2020 the samples were positive in 21.4% of the cases, all of which were for SARS-Cov-2. The period of the year with the highest number of secretion collections was in May and June considering 2019 (60% of 2019 collections), and July, August and December considering 2020 (42.8% of 2020 collections), with a positivity of 77.7% (2019) and 25% (2020) for viruses requested for research. Conclusion: It was possible to notice an important change in the profile of the viruses identified in respiratory conditions between 2019 and 2020, comparable to the profile presented by the Epidemiological Bulletins of the Ministry of Health, especially in the year 2020 with the emergence of the new coronavirus and its pandemic. The viral etiology present in the vast majority of pediatric respiratory conditions should always be valued and viral identification tests are tools of great applicability in the clinic.


Assuntos
Humanos , Criança , Adolescente , Pediatria , Vírus Sinciciais Respiratórios , Coronavirus , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2
17.
Cienc. tecnol. salud ; 8(1): 118-125, 2021. il 27 c
Artigo em Espanhol | LILACS, DIGIUSAC, LIGCSA | ID: biblio-1353017

RESUMO

En Guatemala en el 2015, el Ministerio de Salud Pública y Asistencia Social (MSPAS) reportó nuevos casos de la enfermedad de Chagas en la región suroriental del país, siendo Santa Rosa uno de los departamentos endémicos en donde Triatoma dimidiata es el principal transmisor. Se estimó la infestación de T. dimidiata en la aldea Chuchuapa, municipio de Santa María Ixhuatán, de abril a junio de 2019, se calcularon los índices en-tomológicos y se caracterizaron intra y peridomiciliar 149 viviendas (79.67% de las viviendas habitadas). Los datos se obtuvieron mediante un cuestionario mixto, en entrevista cara a cara y evaluación de las viviendas, por un equipo profesional experimentado, mediante el método y protocolo estándar hombre-hora. Se capturaron 20 triatominos en 10 viviendas, con un índice de infestación de 6.71% (10/149), un índice de densidad de 13.42% (20/149), 19 triatominos intradomiciliares y uno peridomiciliar, con un índice de infección natural por Tr y pano-soma cruzi intradomiciliar de 26.3% (5/19), índice de infección natural por T. cr u z i peridomiciliar de 100.0% (1/1) e índice de infección natural por T. c r u z i en los triatominos capturados de 30.0 % (6/20). Las viviendas infestadas presentaron techo de lámina, pared de bajareque con grietas y sin repello, piso de tierra y afiches en la pared, acumulación de leña u otros materiales tanto intra como peridomiciliar, convivencia con animales domésticos y tenencia de animales de corral. Los resultados representan un alto riesgo para la transmisión de la enfermedad de Chagas entre los habitantes de la aldea.


In Guatemala in 2015, the Ministry of Public Health and Social Assistance reported new cases of Chagas disease in the southeastern region of the country, with Santa Rosa being one of the endemic departments where Tr ia-toma dimidiata is the main transmitter. The infestation of T. dimidiata was estimated in the Chuchuapa village, municipality of Santa María Ixhuatán, from April to June 2019, the entomological indices were calculated and 149 dwellings were characterized intradomiciliary and peridomiciliary (79.67% of the inhabited dwellings). The data were obtained through a mixed questionnaire, in a face-to-face interview and evaluation of the dwellings, by an experienced professional team, using the standard man-hour method and protocol. 20 triatomines were captured in 10 homes, with an infestation index of 6.71% (10/149), a density index of 13.42% (20/149), 19 intradomiciliary triatomines and one peridomiciliary, with a natural infection index by intradomiciliary Trypanosomacruzi of 26.3% (5/19), natural infection index by peridomiciliary T. c r u z i of 100.0% (1/1) and natural infection index by T. c r u z i in captured triatomines of 30.0% (6/20). The infested dwellings have a sheet roof, awattle and daub wall with cracks and no wall plaster, dirt and posters on the wall, accumulation of firewood and other materials in both intradomiciliary and peridomiciliary, living with domestic animals and keeping poultry animals. The results represent a high risk for the transmission of Chagas disease among the villager.


Assuntos
Humanos , Animais , Adulto , Adulto Jovem , Triatoma/parasitologia , Trypanosoma cruzi/isolamento & purificação , Doença de Chagas/transmissão , Habitação , Insetos Vetores/parasitologia , Aves Domésticas , População Rural , Inquéritos Epidemiológicos , Doença de Chagas/epidemiologia , Guatemala/epidemiologia , Animais Domésticos
18.
Anal Chim Acta ; 1132: 1-9, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32980098

RESUMO

Three-dimensional printing techniques have been widely used in the fabrication of new materials applied to energy, sensing and electronics due to unique advantages, such as fast prototyping, reduced waste generation, and multiple fabrication designs. In this paper, the production of a conductive 3D-printing filament composed of Ni(OH)2 microparticles and graphene within a polylactic acid matrix (Ni-G-PLA) is reported. The nanocomposite was characterized by thermogravimetric, energy-dispersive X-ray spectroscopic, scanning electronic microscopic, Raman spectroscopic and electrochemical techniques. Characteristics such as printability (using fused deposition modelling), electrical conductivity and mechanical stability of the polymer nanocomposite were evaluated before and after 3D printing. The novel 3D-printed disposable electrode was applied for selective detection of glucose (enzyme-less sensor) with a detection limit of 2.4 µmol L-1, free from the interference of ascorbic acid, urea and uric acid, compounds typically found in biological samples. The sensor was assembled in a portable electrochemical system that enables fast (160 injection h-1), precise (RSD < 5%) and selective determination of glucose without the need of enzymes (electrocatalytic properties of the Ni-G-PLA nanocomposite). The obtained results showed that Ni-G-PLA is a promising material for the production of disposable sensors for selective detection of glucose using a simple and low-cost 3D-printer.


Assuntos
Técnicas Eletroquímicas , Glucose , Níquel , Condutividade Elétrica , Impressão Tridimensional
19.
Cancers (Basel) ; 12(8)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32707998

RESUMO

Cancer stem cells (CSCs) present chemo-resistance mechanisms contributing to tumour maintenance and recurrence, making their targeting of utmost importance in gastric cancer (GC) therapy. The Hippo pathway has been implicated in gastric CSC properties and was shown to be regulated by leukaemia inhibitory factor receptor (LIFR) and its ligand LIF in breast cancer. This study aimed to determine LIF's effect on CSC properties in GC cell lines and patient-derived xenograft (PDX) cells, which remains unexplored. LIF's treatment effect on CSC markers expression and tumoursphere formation was evaluated. The Hippo kinase inhibitor XMU-MP-1 and/or the JAK1 inhibitor Ruxolitinib were used to determine Hippo and canonical JAK/STAT pathway involvement in gastric CSCs' response to LIF. Results indicate that LIF decreased tumorigenic and chemo-resistant CSCs, in both GC cell lines and PDX cells. In addition, LIF increased activation of LATS1/2 Hippo kinases, thereby decreasing downstream YAP/TAZ nuclear accumulation and TEAD transcriptional activity. LIF's anti-CSC effect was reversed by XMU-MP-1 but not by Ruxolitinib treatment, highlighting the opposite effects of these two pathways downstream LIFR. In conclusion, LIF displays anti-CSC properties in GC, through Hippo kinases activation, and could in fine constitute a new CSCs-targeting strategy to help decrease relapse cases and bad prognosis in GC.

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