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1.
Adv Colloid Interface Sci ; 327: 103157, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626554

RESUMO

Shear thickening fluids (STFs) are a unique type of fluids that can quickly transform into a solid-like state when subjected to forces (rate dependent). These fluids are created by dispersing micro and nanoparticles within a medium. When the force is removed, they return to their original liquid state. Shear thickening fluids can absorb a significant amount of impact energy, making them useful for reducing vibrations and serving as a damper. This study provides a comprehensive and brief overview of existing literature on shear thickening fluids, including their properties, classification, and the rheological mechanisms behind the shear thickening behaviour. It also examines the use of these fluids in various applications, such as improving resistance to stabs and spikes, protecting against low- and high-velocity impacts, and as a new medium for energy dissipation in industries such as battery safety, vibration control and adaptive structures. Lastly, this work reviews the promising combination of STFs with cork. Given the sustainability of cork and its energy absorption capacity, cork-STF composites are a promising solution for various impact-absorbing applications. Overall, the paper underscores the versatility and potential of STFs, and advocates for further research and exploration.

2.
Mol Phylogenet Evol ; 195: 108046, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447924

RESUMO

The global decline of freshwater mussels and their crucial ecological services highlight the need to understand their phylogeny, phylogeography and patterns of genetic diversity to guide conservation efforts. Such knowledge is urgently needed for Unio crassus, a highly imperilled species originally widespread throughout Europe and southwest Asia. Recent studies have resurrected several species from synonymy based on mitochondrial data, revealing U. crassus to be a complex of cryptic species. To address long-standing taxonomic uncertainties hindering effective conservation, we integrate morphometric, phylogenetic, and phylogeographic analyses to examine species diversity within the U. crassus complex across its entire range. Phylogenetic analyses were performed using cytochrome c oxidase subunit I (815 specimens from 182 populations) and, for selected specimens, whole mitogenome sequences and Anchored Hybrid Enrichment (AHE) data on âˆ¼ 600 nuclear loci. Mito-nuclear discordance was detected, consistent with mitochondrial DNA gene flow between some species during the Pliocene and Pleistocene. Fossil-calibrated phylogenies based on AHE data support a Mediterranean origin for the U. crassus complex in the Early Miocene. The results of our integrative approach support 12 species in the group: the previously recognised Unio bruguierianus, Unio carneus, Unio crassus, Unio damascensis, Unio ionicus, Unio sesirmensis, and Unio tumidiformis, and the reinstatement of five nominal taxa: Unio desectusstat. rev., Unio gontieriistat. rev., Unio mardinensisstat. rev., Unio nanusstat. rev., and Unio vicariusstat. rev. Morphometric analyses of shell contours reveal important morphospace overlaps among these species, highlighting cryptic, but geographically structured, diversity. The distribution, taxonomy, phylogeography, and conservation of each species are succinctly described.


Assuntos
Unio , Animais , Filogenia , Filogeografia , Unio/genética , Europa (Continente) , DNA Mitocondrial/genética , Variação Genética
3.
Braz J Biol ; 83: e275678, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126637

RESUMO

The objective of this study was to evaluate reproductive traits in adults of Astyanax lacustris subjected to different spawning inducers. The study involved 240 females (12.54 g ± 2.33 and 7.66 cm ± 0.63 cm) and 240 males (5.83 g ± 0.39 g and 6.14 cm ± 0.64 cm), all at reproductive age. Three different inducers were evaluated: (i) 0.4 pellets of Ovopel®/kg of body weight; (ii) 0.5 ml of buserelin acetate/kg of body weight; and (iii) carp pituitary extract (CPE) (5.5 mg CPE/kg body weight for females and 2.5 mg CPE/kg body weight for males), as well as saline solution (without hormone). The degree-hours for spawning were greater (P<0.05) for the Ovopel® treatment (with 204.93) than in the treatment with CPE (183.2). Ovary weight and gonadosomatic index were higher (P<0.05) in CPE and Ovopel® treatments when compared to buserelin acetate. The number of oocytes per female, absolute and relative fecundity were greater (P<0.05) for Ovopel® and CPE treatments. Fertilization rate was higher (P<0.05) in treatment with buserelin acetate (82.3%) in relation to Ovopel® (72.33%) and CPE (62.40%) treatments, and the highest (P<0.05) hatching rates were achieved with buserelin acetate and Ovopel®. The number of larvae per female body weight was greater (P<0.05) when Ovopel® was used. In conclusion, Ovopel® proves to be a more effective reproductive inducer for induced reproduction of A. lacustris when compared to CPE and buserelin acetate.


Assuntos
Carpas , Characidae , Masculino , Animais , Feminino , Busserrelina/farmacologia , Reprodução , Peso Corporal
4.
Nat Commun ; 14(1): 5000, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37591992

RESUMO

Single Pulse All Optical Switching represents the ability to reverse the magnetization of a nanostructure using a femtosecond single laser pulse without any applied field. Since the first switching experiments carried out on GdFeCo ferrimagnets, this phenomena has been only recently extended to a few other materials, MnRuGa alloys and Tb/Co multilayers with a very specific range of thickness and composition. Here, we demonstrate that single pulse switching can be obtained for a large range of rare earth-transition metal multilayers, making this phenomenon much more general. Surprisingly, the threshold fluence for switching is observed to be independent of the laser pulse duration. Moreover, at high laser intensities, concentric ring domain structures are induced. These striking features contrast to those observed in Gd based materials pointing towards a different reversal mechanism. Concomitant with the demonstration of an in-plane magnetization reorientation, a precessional reversal mechanism explains all the observed features.

5.
ESMO Open ; 8(4): 101615, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37562195

RESUMO

BACKGROUND: Approximately 80% of all breast cancers (BCs) are currently categorized as human epidermal growth factor receptor 2 (HER2)-negative [immunohistochemistry (IHC) 0, 1+, or 2+/in situ hybridization (ISH) negative]; approximately 60% of BCs traditionally categorized as HER2-negative express low levels of HER2. HER2-low (IHC 1+ or IHC 2+/ISH-) status became clinically actionable with approval of trastuzumab deruxtecan to treat unresectable/metastatic HER2-low BC. Greater understanding of patients with HER2-low disease is urgently needed. PATIENTS AND METHODS: This global, multicenter, retrospective study (NCT04807595) included tissue samples from patients with confirmed HER2-negative unresectable/metastatic BC [any hormone receptor (HR) status] diagnosed from 2014 to 2017. Pathologists rescored HER2 IHC-stained slides as HER2-low (IHC 1+ or IHC 2+/ISH-) or HER2 IHC 0 after training on low-end expression scoring using Ventana 4B5 and other assays at local laboratories (13 sites; 10 countries) blinded to historical scores. HER2-low prevalence and concordance between historical scores and rescores were assessed. Demographics, clinicopathological characteristics, treatments, and outcomes were examined. RESULTS: In rescored samples from 789 patients with HER2-negative unresectable/metastatic BC, the overall HER2-low prevalence was 67.2% (HR positive, 71.1%; HR negative, 52.8%). Concordance was moderate between historical and rescored HER2 statuses (81.3%; κ = 0.583); positive agreement was numerically higher for HER2-low (87.5%) than HER2 IHC 0 (69.9%). More than 30% of historical IHC 0 cases were rescored as HER2-low overall (all assays) and using Ventana 4B5. There were no notable differences between HER2-low and HER2 IHC 0 in patient characteristics, treatments received, or clinical outcomes. CONCLUSIONS: Approximately two-thirds of patients with historically HER2-negative unresectable/metastatic BC may benefit from HER2-low-directed treatments. Our data suggest that HER2 reassessment in patients with historical IHC 0 scores may be considered to help optimize selection of patients for treatment. Further, accurate identification of patients with HER2-low BC may be achieved with standardized pathologist training.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/terapia , Neoplasias da Mama/diagnóstico , Estudos Retrospectivos , Prevalência , Receptor ErbB-2/genética , Hibridização In Situ
6.
J Mech Behav Biomed Mater ; 144: 105993, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37385128

RESUMO

Hydroxyapatite (HA) from bovine bones has been used as a biomaterial in dentistry due to its biocompatibility and bioactivity. However, dense HA bioceramics still present inadequate properties for applications that require high mechanical performance, such as infrastructure. Microstructural reinforcements and control of ceramic processing steps are methods to improve these shortcomings. The present study assessed the effects of polyvinyl butyral (PVB) addition in combination with two sintering methodologies (2-step and conventional), on the mechanical properties of polycrystalline bovine HA bioceramics. The samples were divided into four groups (with 15 samples per group): conventional sintering with binder (HBC) and without binder (HWC) and 2-step sintering with (HB2) and without binder (HW2). HA was extracted from bovine bones, turned into nanoparticles in a ball mill, and subjected to uniaxial and isostatic pressing into discs, according to ISO 6872 standards. All groups were characterized by x-ray diffractometry (XRD), differential thermal analysis (DTA) and Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and relative density. Besides, mechanical analyses (biaxial flexural strength (BFS) and modulus of elasticity) were also performed. The characterization results demonstrated that adding agglutinants or the sintering method did not affect HA's chemical and structural characteristics. Even so, the HWC group showed the highest mechanical values for BFS and modulus of elasticity being 109.0 (98.0; 117.0) MPa and 105.17 ± 14.65 GPa, respectively. The HA ceramics submitted to conventional sintering and without the addition of binders achieved better mechanical properties than the other groups. The impacts of each variable were discussed and correlated to the final microstructures and mechanical properties.


Assuntos
Durapatita , Nanopartículas , Animais , Bovinos , Durapatita/química , Materiais Biocompatíveis/química , Espectroscopia de Infravermelho com Transformada de Fourier , Cerâmica/química , Propriedades de Superfície , Teste de Materiais
7.
Rev. neurol. (Ed. impr.) ; 76(7): 243-246, Ene-Jun. 2023.
Artigo em Inglês, Espanhol | IBECS | ID: ibc-218551

RESUMO

Introducción: La miopatía miotubular ligada al X es una miopatía centronuclear rara que afecta aproximadamente a 1 de cada 50.000 recién nacidos varones causada por variantes patógenas en el gen de la miotubularina 1 (MTM1). La gravedad clínica varía; sin embargo, la necesidad de soporte ventilatorio ocurre casi invariablemente. Caso clínico: Presentamos el caso de un niño de 4 años que presentaba hipotonía muscular leve a los 12 meses, trastorno del lenguaje expresivo, retraso global del desarrollo y trastorno del procesamiento sensorial. La secuenciación clínica del exoma identificó la variante hemicigótica c.722G>A p.(Arg241His) en el exón 9 del gen de la miotubularina 1 (NM_000252.2). La madre es portadora heterocigota de la misma variante. Se estableció el diagnóstico de una forma leve de miopatía miotubular ligada al cromosoma X de herencia materna. El niño presentó una mejoría significativa con terapias del habla, ocupacional y física, sin intercurrencias respiratorias ni dependencia de ventilador. Conclusión: La presentación de una forma leve de esta miopatía miotubular, al notificarse más raramente, añadió desafío al diagnóstico. La combinación de hipotonía leve, dificultades de alimentación y trastorno del lenguaje expresivo debe hacer sospechar una enfermedad neuromuscular. Se carece de puntuaciones motoras o de desarrollo verificadas específicas de esta miopatía para determinar el pronóstico y la necesidad de otras terapias. Aunque actualmente la gravedad de la miopatía miotubular se clasifica según la dependencia del ventilador, esto puede ser insuficiente e inaplicable a los casos más leves. Es evidente la necesidad de un sistema de clasificación para los casos leves y moderados que evalúe la debilidad muscular y la fatiga, las limitaciones de la vida diaria, el retraso del desarrollo motor, las puntuaciones fenotípicas tempranas o las infecciones respiratorias recurrentes.(AU)


Introduction: X-linked myotubular myopathy is a rare centronuclear myopathy that affects approximately 1 in 50,000 male newborns caused by pathogenic variants in the myotubularin 1 gene (MTM1). The clinical severity varies, however the need for ventilatory support occurs almost invariably. Case report: We report the case of a 4-year-old boy presenting mild muscle hypotonia at 12 months-old, expressive language disorder, global developmental delay, and a sensory processing disorder. Clinical exome sequencing identified the hemizygous variant c.722G>A p.(Arg241His) in exon 9 of the myotubularin 1 gene (NM_000252.2). The mother is a heterozygous carrier of the same variant. A diagnosis of a mild form of maternal inherited X-linked myotubular myopathy was established. The child presented significant improvement with speech, occupational, and physical therapies, with no respiratory intercurrences or ventilator dependency. Conclusion: The presentation of a mild form of this myotubular myopathy, being less commonly reported, added challenge to the diagnosis. The combination of mild hypotonia, feeding difficulties and expressive language disorder should raise suspicion of a neuromuscular disease. There is a lack of verified motor or developmental scores specific to this myopathy to further determine prognosis and need of other therapies. While currently the severity myotubular myopathy is classified according to ventilator dependency, this may be insufficient and unapplicable to milder cases. There is an evident need for a grading system for mild and moderate cases assessing muscle weakness and fatigue, daily life limitations, motor developmental delay, early phenotypical scores, or recurrent respiratory infections.(AU)


Assuntos
Humanos , Masculino , Criança , Miopatias Congênitas Estruturais , Cromossomo X , Fenótipo , Transtornos da Linguagem , Hipotonia Muscular , Transtornos do Desenvolvimento da Linguagem , Neurologia , Pediatria
8.
J Pediatr Genet ; 12(2): 155-158, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37090824

RESUMO

Early infantile epileptic encephalopathy-64 (EIEE 64), also called RHOBTB2-related developmental and epileptic encephalopathy (DEE), is caused by heterozygous pathogenic variants (EIEE 64; MIM#618004) in the Rho-related BTB domain-containing protein 2 ( RHOBTB2 ) gene. To date, only 13 cases with RHOBTB2-related DEE have been reported. We add to the literature the 14th case of EIEE 64, identified by whole exome sequencing, caused by a heterozygous pathogenic variant in RHOBTB2 (c.1531C > T), p.Arg511Trp. This additional case supports the main features of RHOBTB2-related DEE: infantile-onset seizures, severe intellectual disability, impaired motor functions, postnatal microcephaly, recurrent status epilepticus, and hemiparesis after seizures.

9.
Rev Neurol ; 76(7): 243-246, 2023 04 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36973888

RESUMO

INTRODUCTION: X-linked myotubular myopathy is a rare centronuclear myopathy that affects approximately 1 in 50,000 male newborns caused by pathogenic variants in the myotubularin 1 gene (MTM1). The clinical severity varies, however the need for ventilatory support occurs almost invariably. CASE REPORT: We report the case of a 4-year-old boy presenting mild muscle hypotonia at 12 months-old, expressive language disorder, global developmental delay, and a sensory processing disorder. Clinical exome sequencing identified the hemizygous variant c.722G>A p.(Arg241His) in exon 9 of the myotubularin 1 gene (NM_000252.2). The mother is a heterozygous carrier of the same variant. A diagnosis of a mild form of maternal inherited X-linked myotubular myopathy was established. The child presented significant improvement with speech, occupational, and physical therapies, with no respiratory intercurrences or ventilator dependency. CONCLUSION: The presentation of a mild form of this myotubular myopathy, being less commonly reported, added challenge to the diagnosis. The combination of mild hypotonia, feeding difficulties and expressive language disorder should raise suspicion of a neuromuscular disease. There is a lack of verified motor or developmental scores specific to this myopathy to further determine prognosis and need of other therapies. While currently the severity myotubular myopathy is classified according to ventilator dependency, this may be insufficient and unapplicable to milder cases. There is an evident need for a grading system for mild and moderate cases assessing muscle weakness and fatigue, daily life limitations, motor developmental delay, early phenotypical scores, or recurrent respiratory infections.


TITLE: Miopatía miotubular ligada al cromosoma X: informe clínico y revisión del fenotipo leve.Introducción. La miopatía miotubular ligada al X es una miopatía centronuclear rara que afecta aproximadamente a 1 de cada 50.000 recién nacidos varones causada por variantes patógenas en el gen de la miotubularina 1 (MTM1). La gravedad clínica varía; sin embargo, la necesidad de soporte ventilatorio ocurre casi invariablemente. Caso clínico. Presentamos el caso de un niño de 4 años que presentaba hipotonía muscular leve a los 12 meses, trastorno del lenguaje expresivo, retraso global del desarrollo y trastorno del procesamiento sensorial. La secuenciación clínica del exoma identificó la variante hemicigótica c.722G>A p.(Arg241His) en el exón 9 del gen de la miotubularina 1 (NM_000252.2). La madre es portadora heterocigota de la misma variante. Se estableció el diagnóstico de una forma leve de miopatía miotubular ligada al cromosoma X de herencia materna. El niño presentó una mejoría significativa con terapias del habla, ocupacional y física, sin intercurrencias respiratorias ni dependencia de ventilador. Conclusión. La presentación de una forma leve de esta miopatía miotubular, al notificarse más raramente, añadió desafío al diagnóstico. La combinación de hipotonía leve, dificultades de alimentación y trastorno del lenguaje expresivo debe hacer sospechar una enfermedad neuromuscular. Se carece de puntuaciones motoras o de desarrollo verificadas específicas de esta miopatía para determinar el pronóstico y la necesidad de otras terapias. Aunque actualmente la gravedad de la miopatía miotubular se clasifica según la dependencia del ventilador, esto puede ser insuficiente e inaplicable a los casos más leves. Es evidente la necesidad de un sistema de clasificación para los casos leves y moderados que evalúe la debilidad muscular y la fatiga, las limitaciones de la vida diaria, el retraso del desarrollo motor, las puntuaciones fenotípicas tempranas o las infecciones respiratorias recurrentes.


Assuntos
Miopatias Congênitas Estruturais , Proteínas Tirosina Fosfatases não Receptoras , Masculino , Humanos , Proteínas Tirosina Fosfatases não Receptoras/genética , Miopatias Congênitas Estruturais/diagnóstico , Miopatias Congênitas Estruturais/genética , Miopatias Congênitas Estruturais/patologia , Fenótipo , Éxons , Debilidade Muscular/genética
10.
Braz J Biol ; 83: e264570, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36651449

RESUMO

The constant intensification of aquaculture has considerable increased the stress levels of farmed fish and, consequently, the number and intensity of diseases outbreaks. Thus, studies on fish immune response, especially regarding the interaction of fish leukocytes with potential pathogens and xenobiotics are of great importance in order to develop new prophylactic and curative strategies. We isolated leukocytes from the head kidney of Astyanax lacustris-an important Neotropical fish species for aquaculture and a potential model for Neotropical aquaculture research-using a Percoll centrifugation protocol. The isolated leukocytes were incubated with lipopolysaccharide (LPS), and the expression of genes IL-1ß, IL-8, LysC, and LysG were measured. We assessed the phagocytotic activity of leukocytes using Congo red-dyed yeast, a novel and cost-effective protocol that has been developed in this study. The isolated leukocytes responded to LPS induction, exhibiting strong IL-1ß and IL-8 upregulation, two of the most important pro-inflammatory interleukins for vertebrates immune reponse. The optimal concentration of yeast for the phagocytic assay was 106 cells mL-1, resulting in acceptable phagocytic capacity (PC) but without excess of yeasts during the counting process, ensuring a high precision and accuracy of the method. To the best of our knowledge, the present study is the first to investigate the in vitro gene expression and phagocytic activity of leukocytes isolated from A. lacustris. Our findings will serve as a reference for future studies on the immunology and toxicology of Neotropical fish.


Assuntos
Characidae , Animais , Characidae/genética , Expressão Gênica , Interleucina-8/metabolismo , Leucócitos/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo
11.
Pol J Vet Sci ; 25(2): 295-302, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35861971

RESUMO

Donkeys are a public health concern in the Northeast region of Brazil, with thousands of stray animals. Orchiectomy is an important population control measure; however, the long postoperative period with daily treatment of open wounds in the scrotum makes it difficult to perform a large number of castrations in sheltering centers. We evaluate a novel surgical procedure for orchiectomy in donkeys using parascrotal access. Twelve donkeys were used, divided into two groups: I - submitted to orchiectomy through parascrotal surgical access (novel procedure), and II - submitted to orchiectomy through scrotal access (conventional). Postoperative evaluations consisted of a macroscopic evaluation of the surgical wound (bleeding and intensity of edema), hematological parameters, and peritoneal fluid, which occurred in both groups at the moments (M): M0 - before the surgical procedure. The others moments occurred after surgery: M12 (twelve hours); M24 (twenty-four hours); M48 (forty-eight hours); M72 (seventy-two hours); M8D (eight days); and M16D (sixteen days). The surgical techniques did not generate an important systemic inflammatory response to the point detected by the leukogram, fibrinogen dosage, and peritoneal fluid. The parascrotal technique required long surgery but promoted less bleeding, less edema, and faster healing. The techniques used did not promote sufficient systemic inflammation to alter the number of leukocytes and the fibrinogen concentration; however, evaluation of the peritoneal fluid proved to be important for evaluating inflammatory processes involving the scrotum and inguinal canal. We describe a novel surgical procedure for orchiectomy in Donkeys using a parascrotal access that promoted less risk of bleeding, shorter period of edema, and healing time, but required longer surgery time.


Assuntos
Equidae , Orquiectomia , Animais , Equidae/cirurgia , Fibrinogênio , Masculino , Orquiectomia/veterinária , Escroto/cirurgia
12.
Sci Rep ; 12(1): 10262, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715474

RESUMO

Limited information is available about the effect of mid-pregnancy viral infections on the placental expression of efflux transporters and offspring behavior. We hypothesized that maternal exposure to polyinosinic-polycytidylic acid [poly(I:C)], a synthetic double-stranded RNA viral mimic, would impair placental cell turnover, the expression of selected ABC transporters and adult offspring behavior. C57BL/6 mice were administered poly(I:C) (10 mg/Kg;ip) or vehicle at gestational day (GD) 13.5 (mid-pregnancy). Dams were euthanized for blood collection 4 h after injection, fetal and placental collection at GD18.5 or allowed to deliver spontaneously at term. At GD 13.5, poly(I:C) induced an acute pro-inflammatory response characterized by an increase in maternal plasma levels of IL-6, CXCL-1 and CCL-2/MCP-1. At GD 18.5, poly(I:C) decreased cell proliferation/death in the labyrinthine and increased cell death in the junctional zones, characterizing a disruption of placental cell turnover. Abca1 and Abcg1 immunolabelling was decreased in the labyrinthine zone, whereas Abca1, Abcg1 and breast cancer resistance transporter (Bcrp) expression increased in the junctional zone. Moreover, adult offspring showed motor and cognitive impairments in the Rotarod and T-water maze tests. These results indicate that viral infection during mid-pregnancy may disrupt relevant placental efflux transporters, as well as placental cell turnover and offspring behavior in adult life.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Disfunção Cognitiva , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Disfunção Cognitiva/metabolismo , Feminino , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/metabolismo , Placenta/metabolismo , Poli I-C/farmacologia , Gravidez
13.
Rev. neurol. (Ed. impr.) ; 74(5): 170-173, Mar 1, 2022.
Artigo em Espanhol | IBECS | ID: ibc-217674

RESUMO

Introducción: El síndrome PURA es una condición autosómica dominante poco común causada por variantes patogénicas de novo en el gen PURA y que se caracteriza por un fenotipo multisistémico que incluye retraso del neurodesarrollo global, hipotonía temprana, ausencia de habla, dificultades para alimentarse, hipersomnolencia, epilepsia y trastornos del movimiento. Caso clínico: Presentamos una niña de 9 años con hipotonía y dificultades para alimentarse con retraso del crecimiento desde el período neonatal. A la edad de 3 años era evidente el retraso motor e intelectual, tenía una marcha de base amplia, no hablaba y una respuesta de sobresalto acústico exagerada. Desarrolló estereotipias de mano-boca y epilepsia a los 6 años. La monitorización electroencefalográfica continua de 24 horas reveló una actividad lenta global y una actividad epileptiforme frecuente en las áreas temporal izquierda y centrotemporal. La resonancia magnética del cerebro reveló un retraso en la mielinización. A los 6 años, la secuenciación clínica del exoma identificó una variante patógena heterocigótica en el gen PURA, c.153delA p. (Leu54CysfsTer24). Conclusión: El síndrome PURA tiene características clínicas similares a otros trastornos neurológicos, pero la asociación con algunas características clínicas, no tan comunes en otras entidades neurológicas, como no poder hablar, pero poder seguir órdenes simples, y una respuesta de sobresalto acústico exagerado, deben ser factores de sospecha de síndrome PURA y servir para realizar un análisis genético para confirmar el diagnóstico y proporcionar una intervención multidisciplinar precoz.(AU)


Introduction: PURA syndrome is a rare autosomal dominant condition caused by de novo pathogenic variants in PURA gene and characterized by a multisystemic phenotype that includes global neurodevelopmental delay, early hypotonia, absence of speech, feeding difficulties, hypersomnolence, epilepsy and movement disorders. Case report: We report a 9-year-old girl with hypotonia and feeding difficulties with failure to thrive since the neonatal period. At the age of 3 years motor and intellectual delay were evident, she had a wide-based gait, no speech and an exaggerated acoustic startle response. She developed hand-mouthing stereotypies and epilepsy at 6 years old. The 24 hours continuous electroencephalogram monitoring revealed global slow activity and frequent epileptiform activity in left temporal and centrotemporal areas. The brain MRI revealed delayed myelination. At 6 years old the clinical exome sequencing identified a heterozygous pathogenic variant in the PURA gene, c.153delA p.(Leu54CysfsTer24). Conclusion: PURA syndrome has clinical features similar to other neurological disorders but the association with some clinical features, not as common in other neurological entities, like never being able to speak but being able to follow simple orders and exaggerated acoustic startle response, should raise the suspicion of PURA syndrome and genetic analysis must be performed to confirm the diagnosis and provide early multidisciplinary intervention.(AU)


Assuntos
Humanos , Feminino , Criança , Insuficiência de Crescimento , Transtornos do Desenvolvimento da Linguagem , Deficiência Intelectual , Transtornos dos Movimentos , Doenças do Sistema Nervoso , Desenvolvimento Infantil
14.
Trop Biomed ; 39(1): 1-10, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35225294

RESUMO

The present study aimed to identify larval trematodes shed by snails found in water bodies used by urban communities in a former schistosomiasis endemic area in the state of Piauí, in the Brazilian semiarid region. A malacological survey was performed followed by analysis of the cercariae shed by the snails after light exposure. Biomphalaria straminea specimens (n=1,224) were obtained from all seven collection sites. Cercariae shed by snails were i) single tailed, in which one type of cercariae was identified ( Echinostoma cercariae), and ii) with bifurcated tail (brevifurcate apharyngeate distome, brevifurcate pharyngeate distome, and longifurcate pharyngeate distome [strigeocercaria]). Brevifurcate apharyngeate distome were further examined and the presence of spikes in swimming membranes enabled the identification of Spirorchiidae cercariae in all individuals, demonstrating the absence of cercariae compatible with Schistosoma mansoni . Nevertheless, the accurate diagnosis of S. mansoni circulation in former endemic areas is still necessary.


Assuntos
Biomphalaria , Esquistossomose , Animais , Biomphalaria/parasitologia , Brasil , Vetores de Doenças , Larva , Schistosoma mansoni , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Esquistossomose/transmissão
15.
Nanoscale ; 14(8): 3200-3211, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35147148

RESUMO

Recently, a new two-dimensional carbon allotrope named biphenylene network (BPN) was experimentally realized. The BPN structure consists of four-, six-, and eight-membered rings of sp2-hybridized carbon atoms. In this work, we carried out fully-atomistic reactive (ReaxFF) molecular dynamics simulations to study the mechanical properties and fracture patterns of non-defective and defective (nanocracks) BPN. Results show that, under uniaxial tensile loading, BPN is converted into four distinct morphologies before fracture starts. This conversion process is dependent on the stretching direction. Some of the formed structures contain mainly eight-membered rings, which have different shapes in each morphology. In one of them, a graphitization process occurs before the complete fracture. Importantly, in the presence of nanocracks, no new morphologies are formed. BPN exhibits a distinct fracture process when contrasted to graphene. After the critical strain threshold, the graphene transitions from an elastic to a brittle regime, while BPN can exhibit different inelastic stages. These stages are associated with the appearance of new morphologies. However, BPN shares some of the exceptional graphene properties. BPN Young's modulus and melting point are comparable to graphene, about 1019.4 GPa and 4024 K, respectively.

16.
Rev Neurol ; 74(5): 170-173, 2022 03 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35211951

RESUMO

INTRODUCTION: PURA syndrome is a rare autosomal dominant condition caused by de novo pathogenic variants in PURA gene and characterized by a multisystemic phenotype that includes global neurodevelopmental delay, early hypotonia, absence of speech, feeding difficulties, hypersomnolence, epilepsy and movement disorders. CASE REPORT: We report a 9-year-old girl with hypotonia and feeding difficulties with failure to thrive since the neonatal period. At the age of 3 years motor and intellectual delay were evident, she had a wide-based gait, no speech and an exaggerated acoustic startle response. She developed hand-mouthing stereotypies and epilepsy at 6 years old. The 24 hours continuous electroencephalogram monitoring revealed global slow activity and frequent epileptiform activity in left temporal and centrotemporal areas. The brain MRI revealed delayed myelination. At 6 years old the clinical exome sequencing identified a heterozygous pathogenic variant in the PURA gene, c.153delA p.(Leu54CysfsTer24). CONCLUSION: PURA syndrome has clinical features similar to other neurological disorders but the association with some clinical features, not as common in other neurological entities, like never being able to speak but being able to follow simple orders and exaggerated acoustic startle response, should raise the suspicion of PURA syndrome and genetic analysis must be performed to confirm the diagnosis and provide early multidisciplinary intervention.


TITLE: Síndrome PURA en una niña con retraso grave del desarrollo: un diagnóstico desafiante.Introducción. El síndrome PURA es una condición autosómica dominante poco común causada por variantes patogénicas de novo en el gen PURA y que se caracteriza por un fenotipo multisistémico que incluye retraso del neurodesarrollo global, hipotonía temprana, ausencia de habla, dificultades para alimentarse, hipersomnolencia, epilepsia y trastornos del movimiento. Caso clínico. Presentamos una niña de 9 años con hipotonía y dificultades para alimentarse con retraso del crecimiento desde el período neonatal. A la edad de 3 años era evidente el retraso motor e intelectual, tenía una marcha de base amplia, no hablaba y una respuesta de sobresalto acústico exagerada. Desarrolló estereotipias de mano-boca y epilepsia a los 6 años. La monitorización electroencefalográfica continua de 24 horas reveló una actividad lenta global y una actividad epileptiforme frecuente en las áreas temporal izquierda y centrotemporal. La resonancia magnética del cerebro reveló un retraso en la mielinización. A los 6 años, la secuenciación clínica del exoma identificó una variante patógena heterocigótica en el gen PURA, c.153delA p. (Leu54CysfsTer24). Conclusión. El síndrome PURA tiene características clínicas similares a otros trastornos neurológicos, pero la asociación con algunas características clínicas, no tan comunes en otras entidades neurológicas, como no poder hablar, pero poder seguir órdenes simples, y una respuesta de sobresalto acústico exagerado, deben ser factores de sospecha de síndrome PURA y servir para realizar un análisis genético para confirmar el diagnóstico y proporcionar una intervención multidisciplinar precoz.


Assuntos
Epilepsia , Deficiência Intelectual , Criança , Proteínas de Ligação a DNA/genética , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/genética , Epilepsia/genética , Feminino , Humanos , Deficiência Intelectual/genética , Reflexo de Sobressalto , Fatores de Transcrição/genética
17.
Tropical Biomedicine ; : 1-10, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-936391

RESUMO

@#The present study aimed to identify larval trematodes shed by snails found in water bodies used by urban communities in a former schistosomiasis endemic area in the state of Piauí, in the Brazilian semiarid region. A malacological survey was performed followed by analysis of the cercariae shed by the snails after light exposure. Biomphalaria straminea specimens (n=1,224) were obtained from all seven collection sites. Cercariae shed by snails were i) single tailed, in which one type of cercariae was identified (Echinostoma cercariae), and ii) with bifurcated tail (brevifurcate apharyngeate distome, brevifurcate pharyngeate distome, and longifurcate pharyngeate distome [strigeocercaria]). Brevifurcate apharyngeate distome were further examined and the presence of spikes in swimming membranes enabled the identification of Spirorchiidae cercariae in all individuals, demonstrating the absence of cercariae compatible with Schistosoma mansoni. Nevertheless, the accurate diagnosis of S. mansoni circulation in former endemic areas is still necessary.

18.
Med Oral Patol Oral Cir Bucal ; 26(6): e748-e753, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34704977

RESUMO

BACKGROUND: Kaposi's sarcoma (KS) is an uncommon, multifocal and angioproliferative lesion, which demonstrates a poor prognosis. The aim of the present research was to explore the association of HIV viral load, CD4+ and CD8+ counts and the CD4+/CD8+ ratio on the risk of oral Kaposi's sarcoma (KS) development. MATERIAL AND METHODS: A total of 62 patients were retrieved from March 2008 to October 2020 from the files of two oral pathology centres. Clinical, laboratory and follow-up data were retrieved from their medical files. Poisson regression was used to explore the role of history of immunosuppression and its association with oral KS development. A P-value <0.05 was considered significant. RESULTS: Sixty-two patients were included in the present study (32 with oral KS and 30 with no presentation of lesions anywhere on the body). Patients with oral KS presented a mean age of 32.6 years, and male patients were more affected. The hard palate (15 cases; 46.8%) was the main anatomical site affected. The lesions were mostly presented as swellings (13 cases; 40.6%) and nodules (12 cases; 37.5%). Systemic manifestations were also observed, including candidiasis (4 cases; 12.5%), bacterial infection (3 cases; 9.3%), tuberculosis (3 cases; 9.3%), herpes simplex (3 cases; 9.3%) and pneumonia (3 cases; 9.3%). A significant correlation was observed between HIV viral load, CD4+ count and the CD4+/CD8+ ratio with oral KS development. CONCLUSIONS: HIV viral load, CD4+ count and the CD4+/CD8+ ratio are associated with oral KS development.


Assuntos
Infecções por HIV , Sarcoma de Kaposi , Adulto , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Infecções por HIV/complicações , Humanos , Masculino , Sarcoma de Kaposi/complicações , Carga Viral
19.
Braz. j. biol ; 81(3): 657-664, July-Sept. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153381

RESUMO

Abstract Vegetation cover may show diversity and composition patterns of the soil invertebrate community, as a function of litter quantity and quality in a specific habitat. The objective of this work was to characterize the distribution of edaphic fauna in different monocultures. The study was carried out at Chapada Grande farm in Regeneração, PI. Four monoculture areas were chosen: no-tillage soybean, eucalyptus, pasture, and a preserved native cerrado forest. Soil fauna was collected in a dry and wet period by pitfall traps containing 4% formaldehyde. The edaphic fauna was evaluated by the number of individuals per trap per day, average richness and richness, Shannon diversity index and Pielou uniformity index. Data were submitted to analysis of variance and multivariate Principal Component Analysis (PCA). The highest number of individuals per day trap and of average richness were registered in the pasture, eucalyptus and forest areas in both periods, while soybean showed lower values with predominance of Coleoptera and Formicidae groups. The pasture and forest areas showed of higher Shannon index values in the two evaluated seasons, probably due to higher contributions organic residues in the soil that favors the shelter, feeding and reproduction conditions. Regarding the Pielou index, the soybean system showed higher values in this variable. The Aranae, Coleoptera, Formicidae and Diptera groups predominated in the humid period, while Coleoptera and Formicidae predominated in the dry period. Systems that generate greater accumulation of residues harbor a greater diversity of invertebrates of the edaphic fauna. Seasonality had an effect on all variables analyzed and the wet period showed more expressive values.


Resumo A cobertura vegetal pode mostrar padrões de diversidade e composição da comunidade de invertebrados do solo, em função da quantidade e qualidade da serapilheira em determinado habitat específico. O objetivo deste trabalho foi caracterizar a distribuição da fauna edáfica em diferentes monocultivos. O estudo foi realizado na fazenda Chapada Grande no município de Regeneração, PI. Foram escolhidas quatro áreas de monocultivos: soja em sistema de plantio direto, eucalipto, pastagem, além de uma mata nativa de cerrado preservada. Foram realizadas coletas da fauna do solo, em período seco e úmido, por meio de armadilhas do tipo pitfall contendo 4% de formol. A fauna edáfica foi avaliada pelo número de indivíduos por armadilha por dia, riqueza e riqueza média, índice de diversidade de Shannon e índice de uniformidade de Pielou. Os dados foram submetidos à análise de variância e à análise multivariada de Componentes Principais (ACP). O maior número de indivíduos por armadilha dia e de riqueza média foram registrados nas áreas pastagem, eucalipto e mata nos dois períodos, enquanto que a soja mostrou valores inferiores com predomínio dos grupos Coleoptera e Formicidae. As áreas de pastagem e mata mostraram maiores valores de índice de Shannon nas duas épocas avaliadas provavelmente em função de maiores aportes de resíduos orgânicos no solo que favorece as condições de abrigo, alimentação e reprodução. Em relação ao índice de Pielou o sistema com soja mostrou maiores valores nessa variável. Os grupos Araneae, Coleoptera, Formicidae e Diptera predominaram no período úmido, enquanto Coleoptera e Formicidae se destacaram no período seco. Sistemas que geram maior acúmulo de resíduos abrigam uma maior diversidade de invertebrados da fauna edáfica. A sazonalidade apresentou efeito sobre todas as variáveis analisadas sendo que o período úmido mostrou valores mais expressivos.


Assuntos
Humanos , Animais , Pradaria , Biodiversidade , Solo , Florestas , Ecossistema
20.
Plant Biol (Stuttg) ; 23(6): 1074-1085, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34418258

RESUMO

Water stress affects plant performance at various organisational levels, from morphological to molecular, with a drastic drop in crop yield. Integrative studies involving transcriptomics and physiological data in recognized tolerant species are appropriate strategies to identify and understand molecular and functional processes related to water deficit tolerance. The cashew tree (Anacardium occidentale) is a species naturally adapted to environments with low water availability associated with adverse conditions such as heat, high radiation and salinity. We used an integrative strategy, combining classical physiological measurements with high throughput RNA-seq to understand the main adaptive mechanisms of cashew to water deficit followed by recovery. Physiological analyses indicate that young cashew plants display typical isohydric behaviour. They first exhibit rapid stomatal closure, followed by CO2 assimilation, thus preserving the relative water content, membrane integrity and photosystem II activity. Differential expression was observed in 1733 genes from plant leaves exposed to water deficit stress for 26 days. Among them, 705 were upregulated and 1028 were downregulated. After rewatering, 1330 (76.7%) genes returned to their basal expression level. Transcriptional, combined with physiological data, reveal that cashew plants display high phenotypic plasticity and resilience to acute water deficit, and do not activate senescence pathways. A series of genes/pathways and processes involved with drought tolerance in cashew are evidenced, particularly in carbon metabolism, photosynthesis and chloroplast homeostasis.


Assuntos
Anacardium , Adaptação Fisiológica/genética , Secas , Regulação da Expressão Gênica de Plantas , Fotossíntese , Folhas de Planta , Estresse Fisiológico
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