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1.
Front Pharmacol ; 15: 1381168, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720770

RESUMO

Epigenetic modifications, characterized by changes in gene expression without altering the DNA sequence, play a crucial role in the development and progression of cancer by significantly influencing gene activity and cellular function. This insight has led to the development of a novel class of therapeutic agents, known as epigenetic drugs. These drugs, including histone deacetylase inhibitors, histone acetyltransferase inhibitors, histone methyltransferase inhibitors, and DNA methyltransferase inhibitors, aim to modulate gene expression to curb cancer growth by uniquely altering the epigenetic landscape of cancer cells. Ongoing research and clinical trials are rigorously evaluating the efficacy of these drugs, particularly their ability to improve therapeutic outcomes when used in combination with other treatments. Such combination therapies may more effectively target cancer and potentially overcome the challenge of drug resistance, a significant hurdle in cancer therapy. Additionally, the importance of nutrition, inflammation control, and circadian rhythm regulation in modulating drug responses has been increasingly recognized, highlighting their role as critical modifiers of the epigenetic landscape and thereby influencing the effectiveness of pharmacological interventions and patient outcomes. Epigenetic drugs represent a paradigm shift in cancer treatment, offering targeted therapies that promise a more precise approach to treating a wide spectrum of tumors, potentially with fewer side effects compared to traditional chemotherapy. This progress marks a step towards more personalized and precise interventions, leveraging the unique epigenetic profiles of individual tumors to optimize treatment strategies.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38717911

RESUMO

CONTEXT: The pituitary gland is key for childhood growth, puberty, and metabolism. Pituitary dysfunction is associated with a spectrum of phenotypes, from mild to severe. Congenital Hypopituitarism (CH) is the most commonly reported pediatric endocrine dysfunction with an incidence of 1:4000, yet low rates of genetic diagnosis have been reported. OBJECTIVE: We aimed to unveil the genetic etiology of CH in a large cohort of patients from Argentina. METHODS: We performed whole exome sequencing of 137 unrelated cases of CH, the largest cohort examined with this method to date. RESULTS: Of the 137 cases, 19.1% and 16% carried pathogenic or likely pathogenic variants in known and new genes, respectively, while 28.2% carried variants of uncertain significance. This high yield was achieved through the integration of broad gene panels (genes described in animal models and/or other disorders), an unbiased candidate gene screen with a new bioinformatics pipeline (including genes high loss of function intolerance), and analysis of copy number variants. Three novel findings emerged. First, the most prevalent affected gene encodes the cell adhesion factor ROBO1. Affected children had a spectrum of phenotypes, consistent with a role beyond pituitary stalk interruption syndrome. Second, we found that CHD7 mutations also produce a phenotypic spectrum, not always associated with full CHARGE syndrome. Third, we add new evidence of pathogenicity in the genes PIBF1 and TBC1D32, and report 13 novel candidate genes associated with CH (e.g. PTPN6, ARID5B). CONCLUSION: Overall, these results provide an unprecedented insight into the diverse genetic etiology of hypopituitarism.

3.
Biology (Basel) ; 11(4)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35453681

RESUMO

More women are diagnosed with breast cancer (BC) than any other type of cancer. Although large-scale efforts have completely redefined cancer, a cure remains unattainable. In that respect, new molecular functions of the cell should be investigated, such as post-transcriptional regulation. RNA-binding proteins (RBPs) are emerging as critical post-transcriptional modulators of tumorigenesis, but only a few have clear roles in BC. To recognize new putative breast cancer RNA-binding proteins, we performed integrated in silico analyses of all human RBPs (n = 1392) in three major cancer databases and identified five putative BC RBPs (PUF60, TFRC, KPNB1, NSF, and SF3A3), which showed robust oncogenic features related to their genomic alterations, immunohistochemical changes, high interconnectivity with cancer driver genes (CDGs), and tumor vulnerabilities. Interestingly, some of these RBPs have never been studied in BC, but their oncogenic functions have been described in other cancer types. Subsequent analyses revealed PUF60 and SF3A3 as central elements of a spliceosome-related cluster involving RBPs and CDGs. Further research should focus on the mechanisms by which these proteins could promote breast tumorigenesis, with the potential to reveal new therapeutic pathways along with novel drug-development strategies.

4.
Parasit Vectors ; 14(1): 45, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33436058

RESUMO

BACKGROUND: Steinernema feltiae is an entomopathogenic nematode used in biological control programs with a global distribution. Populations of this species show phenotypic plasticity derived from local adaptation and vary in different traits, such as location and host penetration. The aim of this work was to describe a Chilean isolate of this nematode species, using integrative approaches. METHODS: Nematode morphological and morphometric studies were conducted along with molecular analysis of nuclear genes. The symbiotic bacterium was also identified by sequencing the 16S rRNA gene. Some ecological characteristics were described, including the temperature requirements for the nematode life cycle and the effect of soil water content for optimal reproduction. RESULTS: Morphometric characterization revealed a large intra-specific variability. The isolate identity was also corroborated with the analysis of nuclear genes. Based on the 16S gene, its symbiont bacteria, Xenorhabdus bovienii, was identified. The lowest, optimal and highest temperatures found to limit the infestation and reproduction on Galleria mellonella were 10, 20 and 30 °C, respectively; the emergence from the host larvae occurred approximately 10 days after inoculation. Differences were observed in offspring, and 120 infective juveniles (IJ)/larva was the most prolific dose at 20 °C. The soil water content did not affect the number of IJ invaders, penetration efficacy and IJ emergence time or offspring per larva, but it caused a delay in achieving full mortality at the permanent wilting point with respect to saturation and field capacity. CONCLUSIONS: For the first time, a Chilean isolate of S. feltiae is described in detail considering morphological, molecular and ecological aspects. The isolate was shown to be efficient in soil containing water, with optimal temperatures ranging from 15 to 25 °C for host infestation and production of an abundant offspring; these characteristics would allow its potential use as control agents in a wide geographical area of the country.


Assuntos
Rabditídios/genética , Rabditídios/isolamento & purificação , Animais , Chile , Feminino , Larva/parasitologia , Estágios do Ciclo de Vida , Masculino , Mariposas/parasitologia , Controle Biológico de Vetores , RNA Ribossômico 16S/genética , Rabditídios/anatomia & histologia , Rabditídios/classificação , Infecções por Rhabditida/parasitologia , Simbiose , Temperatura , Xenorhabdus/genética , Xenorhabdus/fisiologia
5.
Rev. chil. ter. ocup ; 12(1): 59-66, ago. 2012. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-704358

RESUMO

Esta investigación tiene como principal propósito identificar las percepciones de adultos mayores no institucionalizados de la ciudad de Punta Arenas, respecto a los cambios producidos en sus rutinas y roles luego del proceso de jubilación, desde el enfoque de la ciencia de la ocupación y la terapia ocupacional en la región de Magallanes y Antártica Chilena. La metodología empleada tiene un enfoque cualitativo. Para la recolección de datos, se utilizó una entrevista semiestructurada y el análisis de información se basa en la teoría fundamentada de Glaser & Strauss (1967). Como principales resultados, se obtiene que la existencia de cambios en las rutinas y roles, incluyen percepciones positivas y negativas asociadas. Además, se identifica que en el desempeño de rutinas y roles de las personas, existe una estrecha relación. Finalmente, se puede concluir que para los adultos mayores, la adaptación a dichos cambios producidos después de vivir el proceso de jubilación, depende de las oportunidades de involucramiento en actividades significativas, junto con la posibilidad de contar con redes de apoyo.


This research has as main purpose to identify the perception of non institutionalized elderly people from Punta Arenas city, on the matter of all changes produce in their routines and roles after the retirement process; seeing from the approach of occupation’s science and occupational therapy in the Magellan and Antarctic Chilean region. The methodology used has a qualitative approach. It was used a semi-structured interview for the data collection, and the analysis information is based upon the grounded theory of Glaser & Strauss (1967). As main results, it was obtained that the existence of changes in the routines and roles, include positive and negative perception associated. Furthermore, it was identified that a narrow relationship exists in the performance of the routines and roles of the people. Lastly, it can be concluded that for elderly people, the adaptation to those changes produced after living the retirement process depends on the opportunities of getting involved in meaningful activities, together with the possibility of counting with support networks.


Assuntos
Feminino , Adulto , Atividades Cotidianas , Aposentadoria/psicologia , Chile , Acontecimentos que Mudam a Vida , Terapia Ocupacional , Percepção , Pesquisa Qualitativa , Apoio Social
6.
Acta odontol. latinoam ; Acta odontol. latinoam;23(3): 188-195, Dec. 2010. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-949660

RESUMO

Dental caries is considered a multi-factorial, infectious, chronic, localized, post-eruptive, transmissible disease that leads to the destruction of dental hard tissue. The recognition of Streptococcus mutans as the major bacterial species involved in dental caries has led to the implementation of prevention and control measures for eliminating or reducing it in oral cavity. The main goal of research on medicinal plants is the search for substances or compounds with antimicrobial activity. The aim of this study was to evaluate the antimicrobial activity of fractions obtained by two methods from Isertia laevis against S. mutans and S. sobrinus. The plant material was collected in Medina (Colombia), at an elevation of 550 meters above sea level. From the ethanol extract of leaves of I. laevis, fractions were obtained by two methods: extraction by column vacuum chromatography (CVC) and extraction by continuous liquid / liquid partitioning (CLLP). The evaluation of the antimicrobial activity of fractions against S. mutans and S. sobrinus was performed by well diffusion and bioautography assays. From the CVC technique, only the methanol and methanol-dichloromethane fractions showed activity against S. mutans and S. sobrinus, with a minimum inhibitory concentration of 2 mg/well. From the CLLP technique, only the dichloromethane fraction showed activity against both microorganisms, with a minimum inhibitory concentration of 1 mg/well. Compounds C1 and C2 were isolated from the three active fractions, and showed a minimum inhibitory concentration of 0.4 mg/well for S. mutans and S. sobrinus, with zones of inhibition measuring 6.5 and 6.2 mm, respectively. In conclusion: 1) the three active fractions of I. laevis showed activity against S. mutans and S. sobrinus, 2) compounds C1 and C2 were present equally in the three active fractions showing activity against the two bacteria, 3) compounds C1 and C2 may be triterpenoid and/or steroidal saponin structures, and 4) the two extraction methods lead equally to obtaining the active fractions.


La caries dental es considerada una enfermedad infecciosa multifactorial, cronica, localizada, poseruptiva y transmisible que conlleva a la destruccion del tejido dental duro. El claro reconocimiento de Streptococcus mutans como la principal especie bacteriana implicada en caries dental, ha conducido a la implementacion de medidas de prevencion y control para la eliminacion o disminucion de este microorganismo en cavidad oral. El objetivo fundamental de la investigacion en plantas medicinales, es la busqueda de sustancias o compuestos con actividad antimicrobiana para ser utilizadas en el control o prevencion de enfermedades infecciosas. En este sentido, en salud bucal muchas sustancias obtenidas de plantas han mostrado actividad antimicrobiana. El objetivo de este estudio fue evaluar la actividad antimicrobiana de fracciones obtenidas de la planta Isertia laevis mediante dos metodologias contra S. mutans y S. sobrinus. El material vegetal se colecto en el municipio de Medina (Cundinamarca- Colombia) situado a una altura de 550 metros sobre el nivel del mar. A partir del extracto etanolico de hojas de I. laevis se obtuvieron fracciones mediante dos metodologias, extraccion por cromatografia en columna al vacio (CCV) y extraccion por fraccionamiento liquido/liquido continuo (FLLC). La evaluacion de la actividad antimicrobiana de las fracciones frente a S. mutans y S. sobrinus se realizo por el metodo de difusion en pozo y bioautografico. De las fracciones obtenidas por CCV, solamente las fracciones metanol y metanol-diclorometano presentaron actividad antimicrobiana sobre S. mutans y S. sobrinus, con una concentracion minima inhibitoria de 2 mg/pozo. De las fracciones obtenidas por FLLC solamente la fraccion diclorometano presento actividad antimicrobiana sobre S. mutans y S. sobrinus, con una concentracion minima inhibitoria de 1 mg/pozo. De las 3 fracciones activas se aislaron los compuestos C1 y C2, que presentaron una concentracion minima inhibitoria de 0.4 mg/pozo tanto para S. mutans como para S. sobrinus con halos de inhibicion, respectivamente, de 6.5 y 6.2 mm. En conclusion, 1. Las fracciones metanol y diclorometano obtenidas por CCV y la fraccion diclorometano obtenida por FLLC de hojas de I. laevis presentaron actividad antimicrobiana sobre S. mutans y S. sobrinus; 2. Los compuestos C1 y C2 presentes por igual en las tres fracciones activas tuvieron accion inhibitoria sobre las dos bacterias en evaluacion; 3. Las pruebas quimicas cualitativas para los compuestos C1 y C2 indican que posiblemente corresponden a estructuras de saponinas triterpenicas y/o esteroidales; y 4. Las dos metodologias de extraccion conducen por igual a la obtencion de las fracciones activas.


Assuntos
Humanos , Streptococcus mutans/efeitos dos fármacos , Extratos Vegetais/farmacologia , Cariostáticos/farmacologia , Streptococcus sobrinus/efeitos dos fármacos , Rubiaceae , Solventes/química , Terpenos/química , Vácuo , Extratos Vegetais/química , Testes de Sensibilidade Microbiana , Cromatografia/métodos , Cromatografia Líquida , Imunodifusão , Etanol/química , Metanol/química , Fracionamento Químico , Cloreto de Metileno/química
7.
Acta Odontol Latinoam ; 23(3): 188-95, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21638958

RESUMO

UNLABELLED: Dental caries is considered a multi-factorial, infectious, chronic, localized, post-eruptive, transmissible disease that leads to the destruction of dental hard tissue. The recognition of Streptococcus mutans as the major bacterial species involved in dental caries has led to the implementation of prevention and control measures for eliminating or reducing it in oral cavity. The main goal of research on medicinal plants is the search for substances or compounds with antimicrobial activity. The aim of this study was to evaluate the antimicrobial activity of fractions obtained by two methods from Isertia laevis against S. mutans and S. sobrinus. The plant material was collected in Medina (Colombia), at an elevation of 550 meters above sea level. From the ethanol extract of leaves of I. laevis, fractions were obtained by two methods: extraction by column vacuum chromatography (CVC) and extraction by continuous liquid/liquid partitioning (CLLP). The evaluation of the antimicrobial activity of fractions against S. mutans and S. sobrinus was performed by well diffusion and bioautography assays. From the CVC technique, only the methanol and methanol-dichloromethane fractions showed activity against S. mutans and S. sobrinus, with a minimum inhibitory concentration of 2 mg/well. From the CLLP technique, only the dichloromethane fraction showed activity against both microorganisms, with a minimum inhibitory concentration of 1 mg/well. Compounds C1 and C2 were isolated from the three active fractions, and showed a minimum inhibitory concentration of 0.4 mg/well for S. mutans and S. sobrinus, with zones of inhibition measuring 6.5 and 6.2 mm, respectively. IN CONCLUSION: 1) the three active fractions of I. laevis showed activity against S. mutans and S. sobrinus, 2) compounds C1 and C2 were presen equally in the three active fractions showing activity against the two bacteria, 3) compounds C1 and C2 may be triterpenoid and/or steroidal saponin structures, and 4) the two extraction methods lead equally to obtaining the active fractions.


Assuntos
Cariostáticos/farmacologia , Extratos Vegetais/farmacologia , Rubiaceae , Streptococcus mutans/efeitos dos fármacos , Streptococcus sobrinus/efeitos dos fármacos , Fracionamento Químico , Cromatografia/métodos , Cromatografia Líquida , Etanol/química , Humanos , Imunodifusão , Metanol/química , Cloreto de Metileno/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Solventes/química , Terpenos/química , Vácuo
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