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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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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Chronic stress disrupts reproductive efficiency. Yet, the manner in which stress disturbs reproduction in goats is currently unknown. The Oaxacan Mixteca region is one of Mexico's poorest, with high levels of deforestation, high ambient temperatures, and lack of water. Native goats of the Oaxacan Mixteca Region live in these stressful conditions, as well as in overcrowded and water restricted conditions. Therefore, the aim of this study was to evaluate the effects of these very stressful conditions on the reproduction of male and female goats. Control group was uncrowded, with daily water supply; stress group was overcrowded, with water restriction. The study was conducted from September 2015 to February 2016; the expression of reproductive behaviour and variations of cortisol levels were assessed. In females, oestradiol and progesterone were evaluated during the oestrous cycle. In males, testosterone levels were evaluated before and during reproductive activity. Sexual behaviour decreased in stressed goats: approaching, tail swishing, urination, vaginal discharge and flank contraction decreased in stressed females. Anogenital sniffing, licking, Flehmen reflex, bleating, mount attempts and mounts decreased in male goats. Cortisol levels in stressed animals were higher compared with control animals. Oestradiol and Progesterone levels in stressed females were significantly lower during the follicular and luteal phase, respectively, compared with control females. Testosterone levels in stressed males were lower than in control males, both before and during reproduction. These results indicate that even though goats from the Oaxacan Mixteca Region are habituated to their environmental conditions, they are still stressed by them, as shown by a higher activation of the adrenal axis in stressed goats than in control goats. High cortisol levels may induce low oestradiol levels in females and low testosterone levels in males, as well as a disruption in the expression of their reproductive behaviour.

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We present a tight-binding parametrization for penta-graphene that correctly describes its electronic band structure and linear optical response. The set of parameters is validated by comparing to ab-initio density functional theory calculations for single-layer penta-graphene, showing a very good global agreement. We apply this parameterization to penta-graphene nanoribbons, achieving an adequate description of quantum-size effects. Additionally, a symmetry-based analysis of the energy band structure and the optical transitions involved in the absorption spectra is introduced, allowing for the interpretation of the optoelectronic features of these systems.

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The search for new optical materials capable of absorbing light in the frequency range from visible to near infrared is of great importance for applications in optoelectronic devices. In this paper, we report a theoretical study of the electronic and optical properties of hybrid structures composed of fullerenes adsorbed on graphene and on graphene nanoribbons. The calculations are performed in the framework of the density functional theory including the van der Waals dispersive interactions. We found that the adsorption of the C 60 fullerenes on a graphene layer does not modify its low energy states, but it has strong consequences for its optical spectrum, introducing new absorption peaks in the visible energy region. The optical absorption of fullerenes and graphene nanoribbon composites shows a strong dependence on photon polarization and geometrical characteristics of the hybrid systems, covering a broad range of energies. We show that an external electric field across the nanoribbon edges can be used to tune different optical transitions coming from nanoribbon-fullerene hybridized states, which yields a very rich electro-absorption spectrum for longitudinally polarized photons. We have carried out a qualitative analysis on the potential of these hybrids as possible donor-acceptor systems in photovoltaic cells.

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In this work, we study the Kondo effect of a quantum dot (QD) connected to leads and to a discrete set of one-particle states provided by a quantum box represented by a quantum ring (QR) pierced by a magnetic flux side attached to the QD. The interplay between the bulk Kondo effect and the so-called Kondo box regime is studied. In this system the QR energies can be continuously modified by the application of the magnetic field. The crossover between these two regimes is analyzed by changing the connection of the QD to the QR from the weak to the strong coupling regime. In the weak coupling regime, the differential conductance develops a sequence of Fano-Kondo anti-resonances due to destructive interference between the discrete quantum ring levels and the conducting Kondo channel provided by the leads. In the strong coupling regime the differential conductance has very sharp resonances when one of the Kondo discrete sub-levels characterizing the Kondo box is tuned by the applied potential. The conductance, the current fluctuations and the Fano coefficient result as being the relevant physical magnitudes to be analyzed to reveal the physical properties of these two Kondo regimes and the crossover region between them. The results were obtained by using the slave boson mean field theory (SBMFT).

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: A theoretical study of electronic and optical properties of graphene nanodisks and nanocones is presented within the framework of a tight-binding scheme. The electronic densities of states and absorption coefficients are calculated for such structures with different sizes and topologies. A discrete position approximation is used to describe the electronic states taking into account the effect of the overlap integral to first order. For small finite systems, both total and local densities of states depend sensitively on the number of atoms and characteristic geometry of the structures. Results for the local densities of charge reveal a finite charge distribution around some atoms at the apices and borders of the cone structures. For structures with more than 5,000 atoms, the contribution to the total density of states near the Fermi level essentially comes from states localized at the edges. For other energies, the average density of states exhibits similar features to the case of a graphene lattice. Results for the absorption spectra of nanocones show a peculiar dependence on the photon polarization in the infrared range for all investigated structures.

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INTRODUCTION: Taurine medicine has been able to open the way to the advance of science and to the adaptation of science to the patient with a bull horn wound so that at present, 95% of patients now survive gorings that were fatal in earlier times. MATERIAL AND METHODS: We carried out a retrospective study, utilizing clinical files from the O'Horán General Hospital in Mérida, Yucatán, Mexico during January 1999 through November 2000 as a data-base. RESULTS: Fifteen patients, all male, were treated for 26 bull horn goring wounds. The most frequently injuried patients ranged in age from 14-30 years. All patients were received at the Trauma Unit within 12 h of goring; gorings most frequently occurred in the town of Oxtcutzab, with from patients. Eight patients of is were bullfighters, all with different professions outside the bullfighting season; there were six spontaneous gorings, and the remaining patient was a cowboy wounded during work. Wounds of eight patients were closed, seven received open treatment. From time of admittance, all patients were administered a triple antibiotic schema, in addition to anti-tetanic gamma globulin and tetanic toxoid. DISCUSSION: We carried out comparisons with our patient bull horn goring treatments and those published in the Surgical Round, Spanish Surgery, and the Mexican Journal of Orthopedics and Traumatology; our results were similian to those found in the international literature.

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