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1.
Gene ; 927: 148723, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38914242

RESUMEN

Satellite DNA (satDNA) consists of tandem repeat sequences that typically evolve rapidly through evolutionary mechanisms, including unequal crossover, transposition events, and others. The evolutionary history of Euchroma gigantea is marked by complex chromosomal evolution between lineages, making this species an interesting model for understanding satDNA evolution at intraspecies level. Therefore, our aim was to comprehend the potential contribution of satDNAs to the greater chromosomal differentiation of evolutionary lineages in E. gigantea by investigating the differential patterns of amplification and contraction of the repeats. To achieve this, we employed de novo identification of satDNA using RepeatExplorer and TAREAN, allowing the satellitome characterization between lineages. A total of 26 satDNA families were identified, ranging from 18 to 1101 nucleotides in length, with most families being shared between individuals/lineages, as predicted by the library hypothesis, except for the satDNA EgiSat21-168 that was absent for Northeast Lineage. The total satDNA content of the individuals was less than 11.2%, and it appeared to increase in two directions following the chromosomal evolution model. Thirteen satDNAs exhibited different patterns of amplification, and nine ones were contracted among individuals. Additionally, most repeats showed a divergence of about 10% for these satDNAs, indicating satellitome differentiation for each lineage/individual. This scenario suggests that the expansion of the satellitome occurred differentially among individuals/lineages of E. gigantea, with the contribution of various DNA turnover mechanisms after geographical isolation, and that they could be involved with karyotype evolution.

2.
Clin Transl Gastroenterol ; 15(4): e00681, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38270249

RESUMEN

INTRODUCTION: High-resolution anoscopy (HRA) is the gold standard for detecting anal squamous cell carcinoma (ASCC) precursors. Preliminary studies on the application of artificial intelligence (AI) models to this modality have revealed promising results. However, the impact of staining techniques and anal manipulation on the effectiveness of these algorithms has not been evaluated. We aimed to develop a deep learning system for automatic differentiation of high-grade squamous intraepithelial lesion vs low-grade squamous intraepithelial lesion in HRA images in different subsets of patients (nonstained, acetic acid, lugol, and after manipulation). METHODS: A convolutional neural network was developed to detect and differentiate high-grade and low-grade anal squamous intraepithelial lesions based on 27,770 images from 103 HRA examinations performed in 88 patients. Subanalyses were performed to evaluate the algorithm's performance in subsets of images without staining, acetic acid, lugol, and after manipulation of the anal canal. The sensitivity, specificity, accuracy, positive and negative predictive values, and area under the curve were calculated. RESULTS: The convolutional neural network achieved an overall accuracy of 98.3%. The algorithm had a sensitivity and specificity of 97.4% and 99.2%, respectively. The accuracy of the algorithm for differentiating high-grade squamous intraepithelial lesion vs low-grade squamous intraepithelial lesion varied between 91.5% (postmanipulation) and 100% (lugol) for the categories at subanalysis. The area under the curve ranged between 0.95 and 1.00. DISCUSSION: The introduction of AI to HRA may provide an accurate detection and differentiation of ASCC precursors. Our algorithm showed excellent performance at different staining settings. This is extremely important because real-time AI models during HRA examinations can help guide local treatment or detect relapsing disease.


Asunto(s)
Neoplasias del Ano , Carcinoma de Células Escamosas , Aprendizaje Profundo , Lesiones Intraepiteliales Escamosas , Humanos , Neoplasias del Ano/diagnóstico , Neoplasias del Ano/patología , Neoplasias del Ano/diagnóstico por imagen , Femenino , Masculino , Persona de Mediana Edad , Lesiones Intraepiteliales Escamosas/patología , Lesiones Intraepiteliales Escamosas/diagnóstico , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico por imagen , Coloración y Etiquetado/métodos , Proctoscopía/métodos , Anciano , Algoritmos , Redes Neurales de la Computación , Ácido Acético , Adulto , Sensibilidad y Especificidad , Lesiones Precancerosas/patología , Lesiones Precancerosas/diagnóstico , Lesiones Precancerosas/diagnóstico por imagen , Canal Anal/patología , Canal Anal/diagnóstico por imagen , Valor Predictivo de las Pruebas
3.
Gene ; 888: 147785, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37689222

RESUMEN

Transposable elements (TEs) are mobile repetitive DNA sequences that can transfer horizontally between species. Due to their mutagenic characteristics, TEs are associated with different evolutionary events, including chromosomal rearrangements that are abundant in the beetle Euchroma gigantea. In order to understand more in depth the impact of TEs on the genomic evolution of E. gigantea, we characterized the E. gigantea mobilome and evaluated the horizontal transfer of Tc1-Mariner elements. Genomic sequencing data was generated on the Illumina Hiseq plataform, from a specimen (Northeast lineage) collected in Recife, Pernambuco - Brazil. The TEs were characterized by two independent approaches based on the clustering and assembly of highly repetitive sequences, the RepeatExplorer and dnaPipeTE. The sequences obtained were further characterized using ORFfinder and CD-Search, to obtain the TEs' potential coding proteins and verify the presence and integrity of known TE domains. Evidence for horizontal transfer was evaluated by nucleotide and protein genetic distance between TEs from E. gigantea and other species and phylogenetic incongruences detected between TEs and hosts phylogenetic trees. The mobilome of E. gigantea represents about 21 to 26% of its genome. This mobilome is composed of TEs from 31 superfamilies, belonging to different classes and most known orders of TEs. Several types of TEs with intact domains were observed with emphasis on Tc1-Mariner suggesting the presence of potentially autonomous elements. This superfamily also stands out for having the greatest abundance and diversity, with TEs being classified into four families. When compared to TEs deposited in databases, Mariner TEs stood out as having the highest nucleotide identity (above 90%) with TEs from phylogenetically distant species, such as ants and bees. Altogether these results suggest that E. gigantea Mariner TEs underwent multiple horizontal transfer events to other insect species.


Asunto(s)
Escarabajos , Humanos , Animales , Escarabajos/genética , Filogenia , Elementos Transponibles de ADN/genética , Genómica , Nucleótidos , Evolución Molecular
4.
RMD Open ; 9(3)2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37652558

RESUMEN

OBJECTIVES: The main goal of this study was to characterise the frequency and phenotype of B, T follicular helper (Tfh) and T follicular regulatory (Tfr) cells in peripheral blood and the cytokine environment present in circulation in children with extended oligoarticular juvenile idiopathic arthritis (extended oligo JIA) and polyarticular JIA (poly JIA) when compared with healthy controls, children with persistent oligoarticular JIA (persistent oligo JIA) and adult JIA patients. METHODS: Blood samples were collected from 105 JIA patients (children and adults) and 50 age-matched healthy individuals. The frequency and phenotype of B, Tfh and Tfr cells were evaluated by flow cytometry. Serum levels of APRIL, BAFF, IL-1ß, IL-2, IL-4, IL-6, IL-10, IL-17A, IL-21, IL-22, IFN-γ, PD-1, PD-L1, sCD40L, CXCL13 and TNF were measured by multiplex bead-based immunoassay and/or ELISA in all groups included. RESULTS: The frequency of B, Tfh and Tfr cells was similar between JIA patients and controls. Children with extended oligo JIA and poly JIA, but not persistent oligo JIA, had significantly lower frequencies of plasmablasts, regulatory T cells and higher levels of Th17-like Tfh cells in circulation when compared with controls. Furthermore, APRIL, BAFF, IL-6 and IL-17A serum levels were significantly higher in paediatric extended oligo JIA and poly JIA patients when compared with controls. These immunological alterations were not found in adult JIA patients in comparison to controls. CONCLUSIONS: Our results suggest a potential role and/or activation profile of B and Th17-like Tfh cells in the pathogenesis of extended oligo JIA and poly JIA, but not persistent oligo JIA.


Asunto(s)
Artritis Juvenil , Interleucina-17 , Humanos , Niño , Interleucina-6 , Subgrupos de Linfocitos T , Citocinas
5.
Toxicon ; 214: 37-46, 2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35562061

RESUMEN

Toads belonging to the Bufonidae family have a pair of paratoid glands that store highly toxic a biological secretion with varied chemical composition, that act as a chemical defense against microbial infections and predators. The paratoid gland secretion (PGS) of bufonids is rich in bioactive steroids, alkaloids, proteins, bufadienolides and bufotoxins. In the present investigation we performed a systematic analysis of the chemical profile of PGS obtained from the Bufonidae toad Rhinella jimi ("Cururu" toad) collected at three different regions of Piauí state, Northeastern Brazil. Our aim was to investigate the PGS variation related to the season of animals collection, geographic distribution and gender of the animals. The methanolic extracts of PGS were analyzed by UPLC-QToF-MS/MS. Principal component analysis (PCA) were applied to the data set obtained by the UPLC-QToF-MS/MS analyses. Among 23 compounds identified, dehydrobufotenine, suberoyl arginine, 3-(N-suberoyl-argininyl) telocinobufagin, 3-(N-suberoyl-argininyl) marinobufagin, telocinobufagin, marinobufagin and 3-(N-suberoyl-argininyl) bufalin were detected in all PGS. Minimal variations in the composition of paratoid secretions of R. jimi were observed related to distinct geographical and seasonal parameters. R. jimi female animals presented the most diverse chemical composition in its PGS. With this comparative study, unprecedented for the species, it was possible to observe that the secretions of the paratoid glands produced by R. jimi from different regions of the state of Piauí, at different times of the year, presented consistent chemical composition, with discrete particularities in the number and nature chemistry of its constituents.


Asunto(s)
Bufonidae , Metanol , Espectrometría de Masas en Tándem , Animales , Brasil/epidemiología , Bufonidae/metabolismo , Femenino , Metanol/metabolismo
6.
Front Med (Lausanne) ; 9: 851532, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35449805

RESUMEN

Juvenile idiopathic arthritis (JIA) is a term that collectively refers to a group of chronic childhood arthritides, which together constitute the most common rheumatic condition in children. The International League of Associations for Rheumatology (ILAR) criteria define seven categories of JIA: oligoarticular, polyarticular rheumatoid factor (RF) negative (RF-), polyarticular RF positive (RF+), systemic, enthesitis-related arthritis, psoriatic arthritis, and undifferentiated arthritis. The ILAR classification includes persistent and extended oligoarthritis as subcategories of oligoarticular JIA, but not as distinct categories. JIA is characterized by a chronic inflammatory process affecting the synovia that begins before the age of 16 and persists at least 6 weeks. If not treated, JIA can cause significant disability and loss of quality of life. Treatment of JIA is adjusted according to the severity of the disease as combinations of non-steroidal anti-inflammatory drugs (NSAIDs), synthetic and/ or biological disease modifying anti-rheumatic drugs (DMARDs). Although the disease etiology is unknown, disturbances in innate and adaptive immune responses have been implicated in JIA development. B cells may have important roles in JIA pathogenesis through autoantibody production, antigen presentation, cytokine release and/ or T cell activation. The study of B cells has not been extensively explored in JIA, but evidence from the literature suggests that B cells might have indeed a relevant role in JIA pathophysiology. The detection of autoantibodies such as antinuclear antibodies (ANA), RF and anti-citrullinated protein antibodies (ACPA) in JIA patients supports a breakdown in B cell tolerance. Furthermore, alterations in B cell subpopulations have been documented in peripheral blood and synovial fluid from JIA patients. In fact, altered B cell homeostasis, B cell differentiation and B cell hyperactivity have been described in JIA. Of note, B cell depletion therapy with rituximab has been shown to be an effective and well-tolerated treatment in children with JIA, which further supports B cell intervention in disease development.

7.
Biomech Model Mechanobiol ; 21(3): 937-951, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35384526

RESUMEN

Birth trauma affects millions of women and infants worldwide. Levator ani muscle avulsions can be responsible for long-term morbidity, associated with 13-36% of women who deliver vaginally. Pelvic floor injuries are enhanced by fetal malposition, namely persistent occipito-posterior (OP) position, estimated to affect 1.8-12.9% of pregnancies. Neonates delivered in persistent OP position are associated with an increased risk for adverse outcomes. The main goal of this work was to evaluate the impact of distinct fetal positions on both mother and fetus. Therefore, a finite element model of the fetal head and maternal structures was used to perform childbirth simulations with the fetus in the occipito-anterior (OA) and OP position of the vertex presentation, considering a flexible-sacrum maternal position. Results demonstrated that the pelvic floor muscles' stretch was similar in both cases. The maximum principal stresses were higher for the OP position, and the coccyx rotation reached maximums of 2.17[Formula: see text] and 0.98[Formula: see text] for the OP and OA positions, respectively. Concerning the fetal head, results showed noteworthy differences in the variation of diameters between the two positions. The molding index is higher for the OA position, with a maximum of 1.87. The main conclusions indicate that an OP position can be more harmful to the pelvic floor and pelvic bones from a biomechanical point of view. On the other side, an OP position can be favorable to the fetus since fewer deformations were verified. This study demonstrates the importance of biomechanical analyses to further understand the mechanics of labor.


Asunto(s)
Presentación en Trabajo de Parto , Madres , Femenino , Feto , Humanos , Recién Nacido , Parto , Diafragma Pélvico/fisiología , Embarazo
8.
Risk Anal ; 42(10): 2231-2242, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34791702

RESUMEN

Recent wastewater analyses performed in care homes for the elderly showed high levels of water pollution resulting from pharmaceutical waste. The way people perceive the environmental risk of pharmaceuticals can contribute to reversing this problem, but the factors that influence risk perception remain relatively unknown. The aims of the study are two-fold. We first focused on exploring the levels of knowledge regarding environment/water pollution due to pharmaceutical residues from the groups responsible for prescribing (health professionals), handling (staff), and consuming pharmaceuticals (residents) in care homes for the elderly. Second, we assessed the environmental risk perception of pharmaceuticals based on two main factors: prescription medication (nonprescribed versus prescribed) and disease severity (milder versus severe disease), accounting for their level of knowledge (deficit versus sufficiency of knowledge). The study was designed based on correlational research. Data were collected in homes for the elderly located in three Southwestern European countries (N = 300), using self-report surveys. Current knowledge was perceived to be low and the need to know more was perceived to be high, across all groups. As hypothesized, results indicated that to assess the environmental risk, participants made use of information that was unrelated to pharmaceutical persistence, bioaccumulation, and toxicity (PBT). Prescribed pharmaceuticals and/or medication used to treat severe diseases were perceived as being more hazardous for the environment. Simple main effects analysis comparing between knowledge levels confirmed that this effect occurred mostly when participants had knowledge deficit for disease severity but not for prescription medication. These misconceptions might discourage taking an active role in reducing the impact of pharmaceutical residues in the environment.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Químicos del Agua , Humanos , Anciano , Monitoreo del Ambiente/métodos , Aguas Residuales , Índice de Severidad de la Enfermedad , Preparaciones Farmacéuticas , Prescripciones , Percepción , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
9.
Cytogenet Genome Res ; 162(7): 391-400, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36724740

RESUMEN

In Dichotomius genus, transposable elements (TE) have been related to chromosome remodeling, genomic evolution, and, possibly, to the speciation process. The objective of this study was to verify the interpopulational and interspecific conservation/variation of Tc1-Mariner elements (possibly autonomous) in Dichotomius species, aiming to identify possible contributions in the speciation process of this group. The analysis was performed on four species of Dichotomius, belonging to the Selenocopris subgenus. We verified the presence of the DsPogo_8 and DsTc1_5 elements by PCR and sequencing. We also isolated and sequenced the 28S and 16S rRNA genes aiming at the phylogenetic reconstruction of the analyzed species. Chromosomal mapping of TEs DsTc1_5 and DsPogo_8 was performed by fluorescent in situ hybridization. The results revealed the presence of the elements in the different species analyzed, except for DsTc1_5 in D. (S.) geminatus. These results suggest a vertical inheritance, with the presence of these elements in the common ancestor of these species. In the analyzed species, the nucleotide similarity of DsTc1_5 was higher than that of the 28S and 16S rRNA genes, suggesting the occurrence of horizontal transfer. The phylogenetic tree indicated that the absence of DsTc1_5 in D. (S.) geminatus is related to stochastic loss of this TE. Chromosomal mapping revealed dispersed signals, with predominance in euchromatic regions and wide variation in the chromosomal localization pattern of DsTc1_5 and DsPogo_8, both interpopulational and interspecific. This variation indicates that DsTc1_5 and DsPogo_8 may have contributed to prezygotic and postzygotic isolation, thus contributing to the speciation of these species.


Asunto(s)
Escarabajos , Animales , Escarabajos/genética , Filogenia , Hibridación Fluorescente in Situ , ARN Ribosómico 16S/genética , Cromosomas , Elementos Transponibles de ADN , Evolución Molecular
10.
Rev. bras. entomol ; 66(4): e20220065, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1407501

RESUMEN

ABSTRACT Describing dung beetle communities in tropical forest remnants located in disturbed/urbanized and conserved areas can provide information about the functioning of these ecosystems and support conservation plans. This study aimed to verify the effect of seasons and bait type on dung beetle communities in remnants of the Atlantic Forest in order to describe their composition and diversity parameters. The study was carried out during both the rainy and dry seasons in periurban and urban remnants. Eighteen pitfall traps baited with feces, carrion, and injured millipedes were established in each site. A total of 3501 individuals and 23 species were recorded. Urban remnant presented higher abundance of individuals in the dry season. On the other hand, in periurban remnant the higher abundance was verified in the rainy season. The diversity was higher in the rainy season in both sites. In urban remnant, Coprophanaeus ensifer was found to be generalist regarding its choice of bait (feces and carrion). The use of injured millipedes as bait allowed the record of the predatory species Deltochilum alpercata. Among the types of bait used, the injured millipedes proved to be very effective, capturing a greater diversity of dung beetles during the rainy season in both remnants, and allowed the collection of specialized, necrophages, and generalists species. Therefore, we propose the use of mixed-bait sampling designs in inventories and surveys to increase the chances of sampling species with different traits or dietary preferences, which are often rare in collections.

11.
Front Psychol ; 12: 661496, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34630197

RESUMEN

Women diagnosed with breast cancer often experience unpleasant emotions, resulting in higher levels of emotional burden and decreased levels of wellbeing and quality of life. The present correlational and cross-sectional study aims to compare the implementation of two regulatory levels, intrapersonal and interpersonal (as social sharing of emotions), and two types of strategies, antecedent-focused and response-focused, and explore their impact on breast cancer patients' perception of quality of life. Sixty-eight women previously diagnosed with the disease participated in this study, with a mean age of 63years old (SD=11.58). Data were collected through a self-report questionnaire to assess emotional experience, intrapersonal regulation, social sharing of emotions, and breast cancer-related wellbeing and quality of life. Data yielded that most of the participants regulated their negative emotions within social interactions and made more use of antecedent-focused strategies to cognitively reformulate the emotional episode. Social and family wellbeing were positively associated with antecedent-focused strategies, as well as intrapersonal and interpersonal regulatory levels. Moreover, the occurrence of sharing episodes and social interactions played an important and beneficial role on patients' perceived quality of life. These findings reinforce the importance of promoting an adaptive intrapersonal regulation among breast cancer patients. Results also suggest that social sharing of emotions is an efficient process to help them to better cope with the psychological and emotional burden of the disease, thus positively influencing the way they perceive their social and family wellbeing, as well as their quality of life.

12.
Genet Mol Biol ; 44(3): e20200417, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34387299

RESUMEN

Several studies about the phylogenetic relationships of the Scarabaeinae subfamily (Coleoptera: Scarabaeidae) have been performed, but some phylogenetic uncertainties persist including the relationship and monophyly of different tribes and some genera. The aim of this study was to characterize the mitogenome of Coprophanaeus ensifer in order to establish its position within the Scarabaeidae family and to contribute to the resolution of some phylogenetic uncertainties. The mitogenome was sequenced on the Illumina HiSeq 4000, assembled using the Mitobim software and annotated in MITOS WebServer. The phylogenetic trees were reconstructed by Bayesian inference. The C. ensifer mitogenome is a molecule of 14,964 bp that contains the number and organization of the genes similar to those of most Coleoptera species. Phylogenetic reconstruction suggests monophyly of the tribe Phanaeini and supports the hypothesis that Coprini is a sister group of Phanaeini. The results also revealed the position of the tribe Oniticellini which is grouped with Onthophagini and Onitini. The geographic distribution of these species that form the most ancestral clade suggests with Scarabaeinae originated in Africa.

13.
Neotrop Entomol ; 50(5): 706-715, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33978918

RESUMEN

The grasshopper Ommexecha virens Serville has low dispersion capacity, and it is regarded as a specialist, only being found in sandy, dry environments with high incidence of sunlight. Considering these aspects, we evaluated the diversity and genetic structure of O. virens natural populations using ISSR (Inter Simple Sequence Repeat) markers. The data pointed to low expected heterozygosity for some populations (HE = 0.06-0.09), probably a consequence of positive inbreeding, which is typical of species showing low or null dispersion indices. Moreover, significant genetic differentiation was observed (FST = 0.50 and GST = 0.51), as well as low number of migrants (Nm = 0.47), indicating that the populations are genetically differentiated. This is likely related to the limitation in dispersing and fragmentation of suitable environment localities colonized by O. virens. The populations of O. virens were structured in three genetic groups associated to different landscapes, revealing the presence of a secondary contact zone, possibly arisen from isolation followed by genetic divergence among populations and subsequent gene flow of divergent individuals of O. virens. At last, we found positive isolation by distance (IBD; r: 0.427; P: 0.025) which is an important factor, since it may be adding to the emergence of reproductive barriers among individuals of O. virens that have been experiencing isolation.


Asunto(s)
Genética de Población , Saltamontes , Animales , Flujo Génico , Variación Genética , Saltamontes/genética , Repeticiones de Microsatélite
14.
Chromosome Res ; 29(2): 203-218, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33638119

RESUMEN

Over the past decades, transposable elements (TEs) have been shown to play important roles shaping genome architecture and as major promoters of genetic diversification and evolution of species. Likewise, TE accumulation is tightly linked to heterochromatinization and centromeric dynamics, which can ultimately contribute to speciation. Despite growing efforts to characterize the repeat landscape of species, few studies have focused on mapping the accumulation profiles of TEs on chromosomes. The few studies on repeat accumulation profiles in populations are biased towards model organisms and inbred lineages. Here, we present a cytomolecular analysis of six mobilome-extracted elements on multiple individuals from a population of a species of wild-captured beetle, Dichotomius schiffleri, aiming to investigate patterns of TE accumulation and uncover possible trends of their chromosomal distribution. Compiling TE distribution data from several individuals allowed us to make generalizations regarding variation of TEs at the gross chromosome level unlikely to have been achieved using a single individual, or even from a whole-genome assembly. We found that (1) transposable elements have differential accumulation profiles on D. schiffleri chromosomes and (2) specific chromosomes have their own TE accumulation landscape. The remarkable variability of their genomic distribution suggests that TEs are likely candidates to contribute to the evolution of heterochromatin architecture and promote high genetic variability in species that otherwise display conserved karyotypes. Therefore, this variation likely contributed to genome evolution and species diversification in Dichotomius.


Asunto(s)
Escarabajos , Elementos Transponibles de ADN , Animales , Escarabajos/genética , Elementos Transponibles de ADN/genética , Evolución Molecular , Genómica , Heterocromatina/genética , Humanos
15.
Comput Methods Programs Biomed ; 200: 105921, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33422852

RESUMEN

BACKGROUND AND OBJECTIVE: During vaginal delivery, several positions can be adopted by the mother to be more comfortable and to help the labor process. The positions chosen are very influenced by factors such as monitoring and intervention during the second stage of labor. However, there is limited evidence to support the most ideal birthing position. This work aims at contributing to a better knowledge associated with the widening of the pubic symphysis and the biomechanics of flexible and non-flexible sacrum positions that can be adopted during the second stage of labor, as well as their resulting pathophysiological consequences. METHODS: A validated computational model composed by the pelvic floor muscles attached to the bones, and a fetus head was used to simulate vaginal deliveries. This model was modified to mimic two birthing positions: one that allows the free movement of the coccyx as in flexible sacrum positions and other in which this movement is more restricted as in non-flexible sacrum positions. The widening of the pubic symphysis was also considered to facilitate the passage of the fetus head. RESULTS: The results obtained showed that, in non-flexible sacrum positions, where the coccyx movement is restricted, occur a rotation of 3.6° of the coccyx and a widening of 6 mm of the pubic symphysis. In contrast, in flexible sacrum positions, where the coccyx is free to move, occur a rotation of 15.7° of the coccyx and a widening of the pubic symphysis of 3 mm, appearing to be more beneficial for the mother's pelvis, but slightly higher stresses were detected in the pelvic floor muscles. CONCLUSIONS: Globally, the results obtained allow to conclude that different birthing positions lead to changes in the female pelvic space, so certain positions can be adopted by the mother during the second stage of labor to reduce the risk of obstructed labor and the development of several dysfunctions. More specifically, flexible sacrum positions, such as kneeling, standing, squatting and sitting positions, are more beneficial for the bone structure of her pelvis as they allow a higher coccyx movement and lower widening of the pubic symphysis.


Asunto(s)
Sínfisis Pubiana , Fenómenos Biomecánicos , Femenino , Pelvis , Postura , Sacro
16.
Front Psychol ; 12: 733050, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35140646

RESUMEN

The world of work has been severely affected by the COVID-19 pandemic due to the high instability observed in the labor market, bringing several new challenges for leaders and employees. The present study aims to analyze the role of organizational and job resources in predicting employees' job insecurity during the first wave of the COVID-19 outbreak, through the mediating role of work engagement. A sample of 207 Portuguese employees participated (Mean age = 45 years old, SD = 9.92), of which 64.7% were women. Data was collected using an online survey, including self-report measures of organizational resources (perceived organizational support), job resources (performance feedback and job autonomy), job insecurity, and work engagement. Data showed that job and organizational resources negatively influenced job insecurity. Moreover, work engagement was a significant mediator of the relation between performance feedback (facet of job resources) and job insecurity. Findings suggest that investing in job and organizational resources can act as protective factors to minimize feelings of job insecurity. Likewise, leaders should foster work engagement among employees to help them balance the relation between these resources and job insecurity, especially in crisis situations. Overall, this study takes a new, underexplored perspective, theoretically bridging organizational and job resources with job insecurity and work engagement during a time of great uncertainty, such as the COVID-19 pandemic.

17.
Int J Numer Method Biomed Eng ; 37(1): e3411, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33131201

RESUMEN

During vaginal delivery, the fetal head molds into an elongated shape to adapt to the birth canal, a process known as fetal head molding. However, excessive molding can occur due to prolonged labor or strong contractions, leading to several disorders on the fetal head. This work aims to perform a numerical study on the biomechanics of fetal head molding by measuring specific diameters and the corresponding molding index. A finite element model of the pelvic floor muscles and the fetal body was used. The fetal head is composed of the skin and soft tissues, the skull with sutures and fontanelles, and the brain. The sutures and fontanelles were modeled with membrane elements and characterized by a visco-hyperelastic constitutive model adapted to a plane stress state. Simulations were performed to replicate the second stage of labor in the vertex presentation and occipito-anterior position. With the introduction of viscoelasticity to assess a time-dependent response, a prolonged second stage of labor resulted in higher molding. The pressure exerted by the birth canal and surrounding structures, along with the presence of the pelvic floor muscles, led to a percentage of molding of 9.1%. Regarding the pelvic floor muscles, a 19.4% reduction on the reaction forces and a decrease of 2.58% in muscle stretching was reported, which indicates that sufficient molding may lead to fewer injuries. The present study demonstrates the importance of focusing on the fetus injuries with non-invasive methods that can allow to anticipate complications during labor.


Asunto(s)
Trabajo de Parto , Parto Obstétrico , Femenino , Feto , Cabeza , Humanos , Embarazo , Cráneo
18.
Zootaxa ; 4834(3): zootaxa.4834.3.6, 2020 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-33056117

RESUMEN

Dichotomius valoisae new species (Coleoptera: Scarabaeidae: Scarabaeinae: Dichotomiini) from Santa Luzia do Itanhi, Sergipe, Brazil, is described based on external differences from its congeners. Diagnostic characters and a brief discussion about its conservation status are provided, as well as an updated identification key to the Dichotomius sericeus (Harold) species group.


Asunto(s)
Escarabajos , Animales , Biodiversidad , Brasil , Bosque Lluvioso
19.
Genet Mol Biol ; 43(3): e20190077, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32542305

RESUMEN

The grasshopper Rhammatocerus brasiliensis shows polymorphism of B chromosomes, but the magnitude of B-chromosome occurrence and the factors that may contribute to their dispersion in the species remain unknown thus far. The present study analyzed the occurrence and dispersion of B chromosomes in R. brasiliensis individuals from 21 populations widely distributed in the Brazilian Northeast. The genetic connectivity between 10 populations was verified through analysis of ISSR markers from 200 individuals. Of the 21 populations, 19 presented individuals with one B chromosome, three with two, and one with three B chromosomes. The B chromosome is of medium size and constitutive heterochromatin (CH) located in the pericentromeric region. A variant B chromosome was observed in three populations, similar in size to that of chromosome X, gap and CH, and located in the terminal region. B chromosome frequencies in different populations varied from 0% to 18,8%, mean 8,5%. The wide distribution of the B chromosome is likely a consequence of the positive gene flow among the analyzed populations. B-chromosome occurrence in populations of R. brasiliensis possibly follows the population genetic structure of the species and, owing to the existence of a variant, its origin may not be recent.

20.
Sensors (Basel) ; 20(10)2020 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-32456364

RESUMEN

In this research work, we present an IoT solution to environment variables using a LoRa transmission technology to give real-time information to users in a Things2People process and achieve savings by promoting behavior changes in a People2People process. These data are stored and later processed to identify patterns and integrate with visualization tools, which allow us to develop an environmental perception while using the system. In this project, we implemented a different approach based on the development of a 3D visualization tool that presents the system collected data, warnings, and other users' perception in an interactive 3D model of the building. This data representation introduces a new People2People interaction approach to achieve savings in shared spaces like public buildings by combining sensor data with the users' individual and collective perception. This approach was validated at the ISCTE-IUL University Campus, where this 3D IoT data representation was presented in mobile devices, and from this, influenced user behavior toward meeting campus sustainability goals.


Asunto(s)
Imagenología Tridimensional , Tecnología , Recolección de Datos , Visualización de Datos , Humanos , Internet de las Cosas
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