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1.
Plants (Basel) ; 12(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37653904

RESUMO

Cnidoscolus aconitifolius (CA) and Porophyllum ruderale (PR) are representative edible plants that are a traditional food source in Mexico. This research aimed to analyze the phytochemical composition and untargeted metabolomics analysis of CA and PR and evaluate their antiproliferative effect in vitro. The phytochemical composition (UPLC-DAD-QToF/MS-ESI) identified up to 38 polyphenols and selected organic acids that were clustered by the untargeted metabolomics in functional activities linked to indolizidines, pyridines, and organic acids. Compared with PR, CA displayed a higher reduction in the metabolic activity of human SW480 colon adenocarcinoma cells (LC50: 10.65 mg/mL), and both extracts increased the total apoptotic cells and arrested cell cycle at G0/G1 phase. PR increased mRNA Apc gene expression, whereas both extracts reduced mRNA Kras expression. Rutin/epigallocatechin gallate displayed the highest affinity to APC and K-RAS proteins in silico. Further research is needed to experiment on other cell lines. Results suggested that CA and PR are polyphenol-rich plant sources exhibiting antiproliferative effects in vitro.

2.
Biology (Basel) ; 12(9)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37759629

RESUMO

Neuroblastoma represents a neoplastic expansion of neural crest cells in the developing sympathetic nervous system and is childhood's most common extracranial solid tumor. The heterogeneity of gene expression in different types of cancer is well-documented, and genetic features of neuroblastoma have been described by classification, development stage, malignancy, and progression of tumors. Here, we aim to analyze RNA sequencing datasets, publicly available in the GDC data portal, of neuroblastoma tumor samples from various patients and compare them with normal adrenal gland tissue from the GTEx data portal to elucidate the gene expression profile and regulation networks they share. Our results from the differential expression, weighted correlation network, and functional enrichment analyses that we performed with the count data from neuroblastoma and standard normal gland samples indicate that the analysis of transcriptome data from 58 patients diagnosed with high-risk neuroblastoma shares the expression pattern of 104 genes. More importantly, our analyses identify the co-expression relationship and the role of these genes in multiple biological processes and signaling pathways strongly associated with this disease phenotype. Our approach proposes a group of genes and their biological functions to be further investigated as essential molecules and possible therapeutic targets of neuroblastoma regardless of the etiology of individual tumors.

3.
Acta Paediatr ; 112(3): 550-556, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463432

RESUMO

AIM: To describe the urine collection methods used in precontinent children presenting at the Paediatric Emergency Department (PED) and compare results and contamination rates. METHODS: Retrospective observational cohort study that included 1678 urine cultures collected in infants <24 months of age between January 2016 and December 2019. Urine cultures were compared based on collection technique, sex and patient age. RESULTS: In total, 60.4% of samples were collected by clean-catch urine collection (CCUC), 26.4% by urethral catheterisation (UC) and 13.2% by urine bag (UB). Contamination rates were 2.9% (95% CI 1.3, 4.4) for UC, 11.3% (95% CI 9.3, 13.2) for CCUC and 23.4% (95% CI 17.8, 29.0) for UB. Significant differences in contamination rates were found between UC and CCUC in the 6-12-month age group (1.9% [95% CI 0.0-4.0] versus 12.0% [95% CI 7.2-16.8] [p < 0.0009]), and between UC and UB for all ages. CONCLUSIONS: CCUC is the most common method for urine culture collection in infants <24 months of age at the PED in our centre. UC has the lowest contamination rates, but significant differences were only observed between CCUC and UC in the 6-12-month age group. CCUC is a non-invasive alternative for urine collection in infants.


Assuntos
Infecções Urinárias , Coleta de Urina , Lactente , Humanos , Criança , Coleta de Urina/métodos , Infecções Urinárias/diagnóstico , Infecções Urinárias/urina , Estudos Retrospectivos , Urinálise , Serviço Hospitalar de Emergência
4.
Rev Cient Odontol (Lima) ; 11(2): e154, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-38288450

RESUMO

Introduction: The aligners have become a preferred alternative in terms of orthodontic treatment, surpassing the choice of conventional brackets, due to the comfort and aesthetics that the aligners represent, however, the final result with this system continues to be a controversial issue. The objective of this review was to verify the effectiveness of the treatment completed with aligners versus conventional brackets. Materials and methods: An exhaustive search was carried out in the PubMed, ScienceDirect, Scopus and Embase databases up to the date of January 5, 2023, including comparative studies that evaluated the final result and treatment time of the aligners compared to conventional braces. Two researchers carefully selected the articles evaluated and analyzed different key topics on the subject. Results: In this study, 8 articles were included, according to the studies, the vast majority did not find significant differences in completion between the compared groups. In addition to this, the treatment time in 3 articles was faster with aligners, in 3 articles it was faster with conventional brackets, and in one article no significant difference was found, so it is not yet established whether a system is faster than the other. Conclusions: Both aligners and conventional fixed orthodontics had good results at the end of orthodontic treatment and presented a similar treatment time, however, the majority of treated cases belonged to malocclusions of medium to low complexity, so these cannot be generalized. findings to all malocclusions.

5.
Nanomaterials (Basel) ; 12(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36234603

RESUMO

All-carbon systems have proven to present interesting transport properties and are often used in electronic devices. Motivated by recent resonant responses measured on graphene/fullerene junction, we propose coupled nanoribbons/carbon-nanotube heterostructures for use as charge filters and to allow tuned transport. These hybrid systems are engineered as a four-terminal device, and we explore multiple combinations of source and collector leads. The armchair-edge configuration results in midgap states when the transport is carried through top/bottom terminals. Such states are robust against the lack of perfect order on the tube and are revealed as sharp steps in the characteristic current curves when a bias potential is turned on. The zigzag-edge systems exhibit differential negative resistance, with features determined by the details of the hybrid structures.

6.
Biol Lett ; 18(2): 20210553, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35193370

RESUMO

Females and males often exhibit different survival in nature, and it has been hypothesized that sex chromosomes may play a role in driving differential survival rates. For instance, the Y chromosome in mammals and the W chromosome in birds are often degenerated, with reduced numbers of genes, and loss of the Y chromosome in old men is associated with shorter life expectancy. However, mosaic loss of sex chromosomes has not been investigated in any non-human species. Here, we tested whether mosaic loss of the W chromosome (LOW) occurs with ageing in wild birds as a natural consequence of cellular senescence. Using loci-specific PCR and a target sequencing approach we estimated LOW in both young and adult individuals of two long-lived bird species and showed that the copy number of W chromosomes remains constant across age groups. Our results suggest that LOW is not a consequence of cellular ageing in birds. We concluded that the inheritance of the W chromosome in birds, unlike the Y chromosome in mammals, is more stable.


Assuntos
Cromossomos Humanos Y , Evolução Molecular , Animais , Aves/genética , Feminino , Humanos , Masculino , Mamíferos/genética , Mosaicismo , Cromossomos Sexuais/genética
7.
Anticancer Res ; 42(2): 885-892, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35093886

RESUMO

BACKGROUND/AIM: The emerging antineoplastics Casiopeínas® induce uncoupling of the respiratory chain, production of reactive oxygen species (ROS), entry of Bax into mitochondria, and exit of Ca2+ and Bcl-2 from them, leading to apoptosis. This study aimed to elucidate whether BAX and BCL2 are necessary for apoptosis. MATERIALS AND METHODS: We silenced BAX and BCL2 by CRISPR-Cas9, assessed ROS and calcium retention capacity (CRC) by spectrofluorometry, and caspase-3 with inmunoblotting in neuroblastoma (NB) cells and 3T3-L1 fibroblasts treated with cisplatin and Casiopeína IIIia (CasIIIia). RESULTS: We observed an increase in O2•- production only in BCL2KO NB cells treated with cisplatin (three-fold) and CasIIIia (five-fold), whereas the production of H2O2 in BCL2KO NB cells treated with cisplatin and CasIIIia increased five-fold and three-fold, respectively. The baseline calcium-retention capacity (CRC) was 1.7 relative fluorescence units (RFU) in both cell types. In BAXKO, cisplatin and CasIIIia increased CRC to ~2.3 RFU, and in BCL2KO, they decreased CRC to ~1.1 RFU. We did not detect caspase-3 in BAXKO NB cells. CONCLUSION: Only BAX is essential for CasIIIia-induced apoptosis.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Neuroblastoma/metabolismo , Proteína X Associada a bcl-2/metabolismo , Cálcio/metabolismo , Linhagem Celular Tumoral , Cisplatino/farmacologia , Inativação Gênica , Humanos , Peróxido de Hidrogênio/metabolismo , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/genética
8.
Pediatr Pulmonol ; 57(1): 253-263, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34633153

RESUMO

OBJECTIVES: To describe the etiology of community-acquired pneumonia (CAP) in hospitalized children in Spain and analyze the predictors of the etiology. HYPOTHESIS: The different etiological groups of pediatric CAP are associated with different clinical, radiographic, and analytical data. DESIGN: Observational, multicenter, and prospective study. PATIENT SELECTION: This study included children aged 1 month to 17 years with CAP, who were hospitalized between April 2012 and May 2019. METHODS: An extensive microbiological workup was performed. The clinical, radiographic, and analytical parameters were analyzed for three etiological groups. RESULTS: Among the 495 children included, at least one causative pathogen was identified in 262 (52.9%): pathogenic viruses in 155/262 (59.2%); atypical bacteria (AB), mainly Mycoplasma pneumonia, in 84/262 (32.1%); and typical bacteria (TyB) in 40/262 (15.3%). Consolidation was observed in 89/138 (64.5%) patients with viral CAP, 74/84 (88.1%) with CAP caused by AB, and 40/40 (100%) with CAP caused by TyB. Para-pneumonic pleural effusion (PPE) was observed in 112/495 (22.6%) patients, of which 61/112 (54.5%) presented a likely causative pathogen: viruses in 12/61 (19.7%); AB in 23/61 (37.7%); and TyB in 26/61 (42.6%). Viral etiology was significantly frequent in young patients and in those with low oxygen saturation, wheezing, no consolidation, and high lymphocyte counts. CAP patients with AB as the etiological agent had a significantly longer and less serious course as compared to those with other causative pathogens. CONCLUSIONS: Viruses and M. pneumoniae are the main causes of pediatric CAP in Spain. Wheezing, young age, and no consolidation on radiographs are indicative of viral etiology. Viruses and AB can also cause PPE. Since only a few cases can be directly attributed to TyB, the indications for antibiotics must be carefully considered in each patient.


Assuntos
Infecções Comunitárias Adquiridas , Pneumonia por Mycoplasma , Vírus , Criança , Infecções Comunitárias Adquiridas/epidemiologia , Humanos , Mycoplasma pneumoniae , Saturação de Oxigênio , Pneumonia por Mycoplasma/complicações , Pneumonia por Mycoplasma/epidemiologia , Estudos Prospectivos , Espanha/epidemiologia
9.
J Pediatr ; 241: 126-132.e3, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34571020

RESUMO

OBJECTIVES: To determine the time to reverse transcription-polymerase chain reaction (RT-PCR) negativity after the first positive RT-PCR test, factors associated with longer time to RT-PCR negativity, proportion of children seroconverting after proven severe acute respiratory syndrome coronavirus 2 infection, and factors associated with the lack of seroconversion. STUDY DESIGN: The Epidemiological Study of Coronavirus in Children of the Spanish Society of Pediatrics is a multicenter study conducted in Spanish children to assess the characteristics of coronavirus disease 2019. In a subset of patients, 3 serial RT-PCR tests on nasopharyngeal swab specimens were performed after the first RT-PCR test, and immunoglobulin G serology for severe acute respiratory syndrome coronavirus 2 antibodies was performed in the acute and follow-up (<14 and ≥14 days after diagnosis) phase. RESULTS: In total, 324 patients were included in the study. The median time to RT-PCR negativity was 17 days (IQR, 8-29 days), and 35% of patients remained positive more than 4 weeks after the first RT-PCR test. The probability of RT-PCR negativity did not differ across groups defined by sex, disease severity, immunosuppressive drugs, or clinical phenotype. Globally, 24% of children failed to seroconvert after infection. Seroconversion was associated with hospitalization, persistence of RT-PCR positivity, and days of fever. CONCLUSIONS: Time to RT-PCR negativity was long, regardless of the severity of symptoms or other patient features. This finding should be considered when interpreting RT-PCR results in a child with symptoms, especially those with mild symptoms. Seroprevalence and postimmunization studies should consider that 11 in 4 infected children fail to seroconvert.


Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , COVID-19/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Soroconversão , Adolescente , COVID-19/epidemiologia , Teste Sorológico para COVID-19 , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Sistema de Registros , Estudos Soroepidemiológicos , Espanha/epidemiologia , Fatores de Tempo
10.
Rev Cient Odontol (Lima) ; 10(3): e117, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38389546

RESUMO

Miniscrews offer the possibility of performing dental movements, minimizing unwanted side effects and enhancing effectiveness. Extra-alveolar miniscrews are ideal as they provide excellent primary stability and avoid anatomical structures. However, in some cases the primary stability is lost before achieving the success of the mechanics used and thus, the most likely causes of failure should be determined. The purpose of this review was to analyze the success rate of infrazygomatic miniscrews, considering their design and the insertion techniques used. Data collection of this literature review was carried out by searching PubMed, Wiley, Google Scholar sites, SCIELO, Elsevier and Dialnet for publication made from 2003 to June 2022. The search was carried out on June 10th, 2022 and the following keywords were used; infrazygomatic crest, miniscrews, anchorage and stability. Different topics were analyzed and discussed highlighting their clinical relevance. After analyzing the 798 articles, 566 were excluded. The remaining articles were re-analyzed and 153 articles were excluded for the title or abstract and 33 articles were excluded for the methodology. Finally, 46 items remained. After thoroughly analyzing all the articles included, this study concluded that the alloy of the miniscrew (stainless steel or titanium), perforation of the maxillary sinus and the placement area (adhered mucosa or mobile mucosa) do not influence the survival of the miniscrew. The evidence also indicates that the percentage of failure is lower in infrazygomatic compared to intraradicular miniscrews. Orthodontists can confidently and safely include infrazygomatic miniscrew in different orthodontic procedures.


Los minitornillos ofrecen la posibilidad de realizar movimientos dentales, lo que minimiza los efectos secundarios no deseados y potencia la eficacia. Los minitornillos extraalveolares son ideales ya que proporcionan una excelente estabilidad primaria y evitan estructuras anatómicas. Sin embargo, en algunos casos se pierde la estabilidad primaria antes de lograr el éxito de la mecánica utilizada y, por lo tanto, se deben determinar las causas más probables de la falla. El propósito de esta revisión fue analizar la tasa de éxito de los minitornillos infracigomáticos, considerando su diseño y las técnicas de inserción utilizadas. La recolección de datos de esta revisión bibliográfica se realizó mediante la búsqueda en PubMed, Wiley, sitios de Google Scholar, SciELO, Elsevier y Dialnet para publicaciones realizadas desde 2003 hasta junio de 2022. La búsqueda se realizó el 10 de junio de 2022 y se utilizaron las siguientes palabras clave: cresta infracigomática, minitornillos, anclaje y estabilidad. Se analizaron y discutieron diferentes temas destacando su relevancia clínica. Tras analizar los 798 artículos, se excluyeron 566. Los restantes fueron reanalizados y 153 resultaron excluidos por el título o resumen, y 33 por la metodología. Finalmente, quedaron 46 artículos. Tras analizar exhaustivamente todos los artículos incluidos, este estudio concluye que la aleación del minitornillo (acero inoxidable o titanio), la perforación del seno maxilar y la zona de colocación (mucosa adherida o mucosa móvil) no influyen en la supervivencia del minitornillo. La evidencia también indica que el porcentaje de fracaso es menor en los minitornillos infracigomáticos en comparación con los intrarradiculares. Los ortodoncistas pueden incluir con confianza y seguridad minitornillos infracigomáticos en diferentes procedimientos de ortodoncia.

11.
Commun Biol ; 4(1): 1418, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34934158

RESUMO

Mosaic loss of the Y chromosome (LOY) is the most frequent chromosomal aberration in aging men and is strongly correlated with mortality and disease. To date, studies of LOY have only been performed in humans, and so it is unclear whether LOY is a natural consequence of our relatively long lifespan or due to exposure to human-specific external stressors. Here, we explored whether LOY could be detected in rats. We applied a locus-specific PCR and target sequencing approach that we used as a proxy to estimate LOY in 339 samples covering eleven tissues from young and old individuals. We detected LOY in four tissues of older rats. To confirm the results from the PCR screening, we re-sequenced 60 full genomes from old rats, which revealed that the Y chromosome is the sole chromosome with low copy numbers. Finally, our results suggest that LOY is associated with other structural aberrations on the Y chromosome and possibly linked to the mosaic loss of the X chromosome. This is the first report, to our knowledge, demonstrating that the patterns of LOY observed in aging men are also present in a rodent, and conclude that LOY may be a natural process in placental mammals.


Assuntos
Envelhecimento/genética , Variação Genética , Monossomia , Cromossomo Y/patologia , Fatores Etários , Animais , Masculino , Ratos , Ratos Wistar
12.
Entramado ; 17(2): 256-267, jul.-dic. 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1360426

RESUMO

RESUMEN En Colombia la enfermedad más limitante en el cultivo de la granadilla es la pudrición del cuello causada por Fusarium solani f.sp. passiflorae. Este patógeno afecta a las plantas en todos los estados de desarrollo en la base de los tallos y causa la muerte en un corto tiempo. El objetivo de esta investigación fue evaluar la resistencia en dieciocho especies de la familia Passifloraceae a la pudrición del cuello. Para este experimento se utilizó un aislamiento altamente virulento según los resultados de las pruebas de patogenicidad con plantas de granadilla. Según los resultados después de la inoculación con el patógeno once especies de Passifloras fueron susceptibles, en contraste cinco genotipos de maracuyás (PE10, PE11, PE13, PE15 y PE17) y dos cholupas (PM02 y PM04), fueron resistentes no manifestaron síntomas. Se recomienda utilizar las especies resistentes para el mejoramiento genético de esta especie o emplearlos como porta injertos.


ABSTRACT In Colombia the most limiting disease in the cultivation of granadilla is neck rot caused by Fusarium solani f.sp, passiflorae. This pathogen affects plants in all stages of development at the base of the stems and causes death in a short time. The objective of this research was to evaluate the resistance in eighteen species of the Passifloraceae family to neck rot. For this experiment, a highly virulent isolate was used according to the results of pathogenicity tests with passion fruit plants. According to the results after inoculation with the pathogen, eleven Passifloras species were susceptible, in contrast, five passion fruit genotypes (PE10, PE11, PE13, PE15 and PE17) and two cholupas (PM02 and PM04), were resistant and did not show symptoms. It is recommended to use resistant species for the genetic improvement of this species or to use them as rootstock.


RESUMO Na Colômbia, a doença mais limitante no cultivo do granadilla é a podridão do pescoço causada pelo Fusarium solani f.sp, passiflorae. Este patógeno afeta as plantas em todos os estágios de desenvolvimento na base dos caules e causa a morte em um curto espaço de tempo. O objetivo desta pesquisa era avaliar a resistência de dezoito espécies da família Passifloraceae à podridão do colar Para esta experiência, foi utilizado um isolado altamente virulento de acordo com os resultados dos testes de patogenicidade em plantas de maracujá. De acordo com os resultados após a inoculação com o patógeno onze espécies de Passifloraceae eram suscetíveis, em contraste, cinco genótipos de maracujá (PE10, PE11, PE13, PE15 e PE17) e dois cholupas (PM02 e PM04) eram resistentes e não apresentavam sintomas. Recomenda-se usar as espécies resistentes para o melhoramento genético desta espécie ou usá-las como porta-enxertos.

13.
Pediatr Nephrol ; 36(12): 3899-3904, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34100109

RESUMO

BACKGROUND: Methods of urine collection used in precontinent children are a controversial issue. Definitive diagnosis of urinary tract infection (UTI) requires an uncontaminated urine culture. We aimed to describe methods used to collect urine for culture in infants under 3 months of age and compare results and contamination rates. METHODS: This retrospective observational cohort study included 721 urine cultures collected from infants <3 months of age at the Hospital Universitario Infanta Sofía, Madrid, between January 2016 and December 2019. Urine cultures were compared based on collection technique, sex, and patient age. RESULTS: Median patient age was 36 days and 54.6% were male. In total, 592 (82.1%) samples were collected using clean-catch urine stimulation technique (CCUST), 77 (10.7%) by urethral catheterization (UC) and 52 (7.2%) by urine bag (UB). Positive cultures were obtained in 11.7% (95% confidence interval [CI] 9.1, 14.3) of CCUST samples and in 28.6% (95% CI 18.5, 38.7) of UC samples (p<0.001). The contamination rate was 13.7% (95% CI 10.9, 16.4] for CCUST, 23.1% (95% CI 11.6, 34.6) for UB and 5.2% (95% CI 0.2, 10.2) for UC, with statistically significant differences (p=0.007) between UB and UC collection. CONCLUSIONS: CCUST is the most commonly used method in our hospital for collecting urine in infants younger than 3 months. The contamination rate of UC is lower but not significantly different to that of CCUST. Urine collection by CCUST serves as a non-invasive alternative to UC for diagnosis of UTI in infants under 3 months of age in routine clinical practice. Graphical abstract.


Assuntos
Infecções Urinárias , Coleta de Urina , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Espanha , Urinálise , Cateterismo Urinário , Infecções Urinárias/diagnóstico , Infecções Urinárias/epidemiologia , Coleta de Urina/métodos
14.
Genome Biol Evol ; 12(11): 2015-2028, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-32790864

RESUMO

Placental mammals present 180 million-year-old Y chromosomes that have retained a handful of dosage-sensitive genes. However, the expression evolution of Y-linked genes across placental groups has remained largely unexplored. Here, we expanded the number of Y gametolog sequences by analyzing ten additional species from previously unexplored groups. We detected seven remarkably conserved genes across 25 placental species with known Y repertoires. We then used RNA-seq data from 17 placental mammals to unveil the expression evolution of XY gametologs. We found that Y gametologs followed, on average, a 3-fold expression loss and that X gametologs also experienced some expression reduction, particularly in primates. Y gametologs gained testis specificity through an accelerated expression decay in somatic tissues. Moreover, despite the substantial expression decay of Y genes, the combined expression of XY gametologs in males is higher than that of both X gametologs in females. Finally, our work describes several features of the Y chromosome in the last common mammalian ancestor.


Assuntos
Evolução Biológica , Eutérios/genética , Expressão Gênica , Genes Ligados ao Cromossomo X , Genes Ligados ao Cromossomo Y , Animais , Sequência de Bases , Sequência Conservada , Mecanismo Genético de Compensação de Dose , Feminino , Humanos , Masculino , Especificidade de Órgãos
15.
Genome Biol Evol ; 12(6): 924-930, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32433751

RESUMO

The water skinks Eulamprus tympanum and Eulamprus heatwolei show thermally induced sex determination where elevated temperatures give rise to male offspring. Paradoxically, Eulamprus species reproduce in temperatures of 12-15 °C making them outliers when compared with reptiles that use temperature as a cue for sex determination. Moreover, these two species are among the very few viviparous reptiles reported to have thermally induced sex determination. Thus, we tested whether these skinks possess undetected sex chromosomes with thermal override. We produced transcriptome and genome data for E. heatwolei. We found that E. heatwolei presents XY chromosomes that include 14 gametologs with regulatory functions. The Y chromosomal region is 79-116 Myr old and shared between water and spotted skinks. Our work provides clear evidence that climate could be useful to predict the type of sex determination systems in reptiles and it also indicates that viviparity is strictly associated with sex chromosomes.


Assuntos
Lagartos/genética , Cromossomos Sexuais , Processos de Determinação Sexual , Viviparidade não Mamífera/genética , Animais , Feminino , Masculino
16.
PLoS One ; 15(1): e0221681, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923208

RESUMO

DNA repair inhibition has been described as an essential event leading to the initiation of carcinogenesis. In a previous study, we observed that the exposure to metal mixture induces changes in the miR-nome of the cells that was correlated with the sub-expression of mRNA involved in processes and diseases associated with metal exposure. From this analysis, one of the miRNAs that shows changes in its expression is miR-222, which is overexpressed in various cancers associated with exposure to metals. In silico studies showed that a possible target for the microRNA-222 could be Rad 51c, a gene involved in the double-stranded DNA repair. We could appreciate that up-regulation of miR-222 reduces the expression both gene and as a protein expression of Rad51c by RT-PCR and immunoblot, respectively. A luciferase assay was performed to validate Rad51c as miR-222 target. Neutral comet assay was performed in order to evaluate DNA double-strand breaks under experimental conditions. Here, we demonstrate that miR-222 up-regulation, directly regulates Rad51c expression negatively, and impairs homologous recombination of double-strand break DNA repair during the initiation stage of cell transformation. This inhibition triggers morphological transformation in a two-stage Balb/c 3T3 cell assay, suggesting that this small RNA acts as an initiator of the carcinogenesis process.


Assuntos
Transformação Celular Neoplásica/genética , Proteínas de Ligação a DNA/genética , MicroRNAs/genética , Neoplasias/genética , Células 3T3 , Animais , Simulação por Computador , DNA/efeitos dos fármacos , DNA/genética , Reparo do DNA/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Recombinação Homóloga/efeitos dos fármacos , Recombinação Homóloga/genética , Humanos , Metais/metabolismo , Camundongos
17.
Cell Physiol Biochem ; 53(6): 910-920, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31769258

RESUMO

BACKGROUND/AIMS: Exposure to heavy metals is today a threat to society. The understanding of the molecular processes related to diseases related to exposure to metals mixture involve changes in the expression of microRNAs. Changes on microRNAs expression may alter several cellular processes, among them, DNA repair inhibition has been described as an essential event leading to the initiation of metal-induced carcinogenesis. METHODS: We evaluate the miR-222 expression in the two-stage transformation Balb/c 3T3 cell assay treated with As-Cd-Pb mixture. RESULTS: We could appreciate that up-regulation of miR-222 reduces the expression both gene and as a protein expression of Rad51c by RT-PCR and immunoblot, respectively. CONCLUSION: Here, we demonstrate that the mixture of As-Cd-Pb at epidemiologically relevant concentrations induces miR-222 up-regulation, which directly negatively regulates Rad51c expression and impairs homologous recombination of DNA during the initiation stage of cell transformation. This inhibition triggers morphological transformation in a murine two-stage Balb/c 3T3 cell assay, suggesting that this small RNA acts as an initiator of the carcinogenesis process.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Metais Pesados/farmacologia , MicroRNAs/metabolismo , Rad51 Recombinase/metabolismo , Animais , Antagomirs/metabolismo , Arsênio/química , Células 3T3 BALB , Cádmio/química , Sobrevivência Celular/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Proteínas de Ligação a DNA , Chumbo/química , Camundongos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Rad51 Recombinase/genética
18.
Genome Biol Evol ; 11(11): 3054-3067, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31605487

RESUMO

The age of sex chromosomes is commonly obtained by comparing the substitution rates of XY gametologs. Coupled with phylogenetic reconstructions, one can refine the origin of a sex chromosome system relative to specific speciation events. However, these approaches are insufficient to determine the presence and duration of ancestral sex chromosome systems that were lost in some species. In this study, we worked with genomic and transcriptomic data from mammals and squamates and analyzed the effect of male mutation bias on X-linked sequences in these groups. We searched for signatures indicating whether monotremes shared the same sex chromosomes with placental mammals or whether pleurodonts and acrodonts had a common ancestral sex chromosome system. Our analyses indicate that platypus did not share the XY chromosomes with placental mammals, in agreement with previous work. In contrast, analyses of agamids showed that this lineage maintained the pleurodont XY chromosomes for several million years. We performed multiple simulations using different strengths of male mutation bias to confirm the results. Overall, our work shows that variations in substitution rates due to male mutation bias could be applied to uncover signatures of ancestral sex chromosome systems.


Assuntos
Filogenia , Cromossomos Sexuais , Animais , Cromossomos de Mamíferos , Eutérios/genética , Evolução Molecular , Feminino , Genoma , Lagartos/genética , Masculino , Monotremados/genética , Mutação , Cromossomos Sexuais/genética , Cromossomo X , Cromossomo Y
19.
Sci Rep ; 9(1): 12754, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484950

RESUMO

We analyze the symmetry and topological features of a family of materials closely related to penta-graphene, derived from it by adsorption or substitution of different atoms. Our description is based on a novel approach, called topological quantum chemistry, that allows to characterize the topology of the electronic bands, based on the mapping between real and reciprocal space. In particular, by adsorption of alkaline (Li or Na) atoms we obtain a nodal line metal at room temperature, with a continuum of Dirac points around the perimeter of the Brillouin zone. This behavior is also observed in some substitutional derivatives of penta-graphene, such as penta-PC2. Breaking of time-reversal symmetry can be achieved by the use of magnetic atoms; we study penta-MnC2, which also presents spin-orbit coupling and reveals a Chern insulator phase. We find that for this family of materials, symmetry is the source of protection for metallic and nontrivial topological phases that can be associated to the presence of fractional band filling, spin-orbit coupling and time-reversal symmetry breaking.

20.
Entramado ; 15(1): 298-309, ene.-jun. 2019. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1090219

RESUMO

Resumen La enfermedad fungosa más limitante del duraznero (Prunus pérsica, L. Batsch) en Colombia es la pudrición parda, Monilia spp., que afecta flores, brotes y frutos, causando pérdidas hasta del 80%. El objetivo de la investigación fue identificar el patógeno asociado a pudrición parda en cuatro variedades: Dorado, Rubidoux, Diamante y Rey negro en el departamento de Boyacá. El estudio inicio con la colecta de frutos enfermos en Jenesano, Paipa, Tuta, Sotaquirá y Nuevo Colón. En laboratorio se realizó la obtención, aislamiento y purificación de los hongos presentes. Se realizó también caracterización morfológica de las colonias y conidias sobre cultivos monospóricos y caracterización molecular mediante amplificación por PCR del ADN ribosomal empleando iniciadores ITS4 e ITS5. Se obtuvieron 32 aislamientos del género Monilia y se identificaron tres especies presentes en la zona muestreada: Monilia fructícola, Monilia fructígena y Monilia laxa, en 62,5%, 25% y 12,5%, respectivamente. En la amplificación de la región ribosomal se observaron diferencias entre las dos primeras especies, en el tamaño de las bases amplificadas, siendo M. fructicola de 550 pb y M. fructigena de 545pb. Este trabajo contribuye a la caracterización de las especies de Monilia que afectan al duraznero en varias regiones del departamento de Boyacá.


Abstract The most limiting fungal disease in peach crop (Prunus pérsica, L. Batsch) in Colombia is brown rot, Monilia spp., that affects flowers, buds and fruits, with economic losses of up to 80%. The objective of this work was to identify the pathogen associated with the brown rot in four varieties: Dorado, Rubidoux, Diamante and Rey Negro in Boyacá department. The study started collecting symptomatic fruits in Jenesano, Paipa, Tuta, Sotaquirá and Nuevo Colón. In laboratory were obtained, isolated and purified the fungi present. Also morphological characterization of colonies and conidia were done on monosporic cultures and molecular characterization through PCR amplification of the ribosomal DNA using ITS4 and ITS5 primers. It were obtained 32 isolates of Monilia and three species were identified in the sampled area: Monilia fructícola, Monilia fructígena and Monilia laxa, in a 62.5%, 25% and 12.5%, respectively. In the amplification of the ribosomal region, differences could be observed between the first two species, in the size of the amplified bases, being M. fructicola of 550 bp and M. fructigena of 545 bp. This work contributes to the characterization of the Monilia species that affect the peach tree in several regions of Boyaca's department.


Resumo O mais limitante pêssego doença fúngica (Prunus persica L. Batsch) na Colômbia é o da podridão castanha, Monilia spp., Afectando flores, botões e frutos, causando uma perda de até 80%. O objetivo da pesquisa foi identificar o patógeno associado à podridão parda em quatro variedades: Dorado, Rubidoux, Diamante e Rey negro no departamento de Boyacá. O estudo começou com a coleta de frutas doentes em Jenesano, Paipa, Tuta, Sotaquirá e Nuevo Colón. No laboratório foi realizada a obtenção, isolamento e purificação dos fungos presentes. Caracterização morfológica das colónias e conídios em culturas de esporos e caracterização molecular também foi realizado por amplificação por PCR utilizando iniciadores de ADN ribossomal e ITS4 ITS5. 32 isolados foram obtidos género Monilia e três espécies presentes na área amostrada identificado: Monilia fructicola Monilia laxa, Monilia fructigena e em 62,5%, 25% e 12,5%, respectivamente. Na amplificação da região ribossomais diferenças entre as duas primeiras espécies que foram observados no tamanho das bases amplificados, sendo 550bp M. fructicola e M. fructigena de 545pb. Este trabalho contribui para a caracterização das espécies de Monilia que afetam o pessegueiro em diversas regiões do departamento de Boyacá

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