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In mammals, the central circadian oscillator is located in the suprachiasmatic nucleus (SCN). Hypothalamus-pituitary-thyroid axis components exhibit circadian oscillation, regulated by both central clock innervation and intrinsic circadian clocks in the anterior pituitary and thyroid glands. Thyroid disorders alter the rhythmicity of peripheral clocks in a tissue-dependent response; however, whether these effects are influenced by alterations in the master clock remains unknown. This study aimed to characterize the effects of hypothyroidism on the rhythmicity of SCN, body temperature (BT) and metabolism, and the possible mechanisms involved in this signalling. C57BL/6J adult male mice were divided into Control and Hypothyroid groups. Profiles of spontaneous locomotor activity (SLA), BT, oxygen consumption ( V Ì O 2 ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ ) and respiratory quotient (RQ) were determined under free-running conditions. Clock gene expression, and neuronal activity of the SCN and medial preoptic nucleus (MPOM) area were investigated in light-dark (LD) conditions. Triiodothyronine (T3) transcriptional regulation of Bmal1 promoter activity was evaluated in GH3-transfected cells. Hypothyroidism delayed the rhythmicity of SLA and BT, and altered the expression of core clock components in the SCN. The activity of SCN neurons and their outputs were also affected, as evidenced by the loss of circadian rhythmicity in V Ì O 2 ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ and RQ and alterations in the neuronal activity pattern of MPOM. In GH3 cells, T3 increased Bmal1 promoter activity in a time-dependent manner. Thyroid hormone may act as a temporal cue for the central circadian clock, and the uncoupling of central and peripheral clocks might contribute to a wide range of metabolic and thermoregulatory impairments observed in hypothyroidism. KEY POINTS: Hypothyroidism alters clock gene expression in the suprachiasmatic nucleus (SCN). Thyroid hypofunction alters the phase of spontaneous locomotor activity and body temperature rhythms. Thyroid hormone deficiency alters the daily pattern of SCN and medial preoptic nucleus neuronal activities. Hypothyroidism alterations are extended to daily oscillations of oxygen consumption and metabolism, which might contribute to the development of metabolic syndrome. Triiodothyronine increases Bmal1 promoter activity acting as temporal cue for the central circadian clock.
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Factores de Transcripción ARNTL , Hipotiroidismo , Ratones Endogámicos C57BL , Núcleo Supraquiasmático , Triyodotironina , Animales , Masculino , Hipotiroidismo/fisiopatología , Hipotiroidismo/metabolismo , Hipotiroidismo/genética , Factores de Transcripción ARNTL/genética , Factores de Transcripción ARNTL/metabolismo , Ratones , Núcleo Supraquiasmático/metabolismo , Núcleo Supraquiasmático/fisiología , Ritmo Circadiano/fisiología , Temperatura Corporal/fisiología , Relojes Circadianos/genética , Relojes Circadianos/fisiología , Regulación de la Expresión GénicaRESUMEN
BACKGROUND: Naturally occurring colorectal cancers (CRC) in rhesus macaques share many features with their human counterparts and are useful models for cancer immunotherapy; but mechanistic data are lacking regarding the comparative molecular pathogenesis of these cancers. METHODS: We conducted state-of-the-art imaging including CT and PET, clinical assessments, and pathological review of 24 rhesus macaques with naturally occurring CRC. Additionally, we molecularly characterized these tumors utilizing immunohistochemistry (IHC), microsatellite instability assays, DNAseq, transcriptomics, and developed a DNA methylation-specific qPCR assay for MLH1, CACNA1G, CDKN2A, CRABP1, and NEUROG1, human markers for CpG island methylator phenotype (CIMP). We furthermore employed Monte-Carlo simulations to in-silico model alterations in DNA topology in transcription-factor binding site-rich promoter regions upon experimentally demonstrated DNA methylation. RESULTS: Similar cancer histology, progression patterns, and co-morbidities could be observed in rhesus as reported for human CRC patients. IHC identified loss of MLH1 and PMS2 in all cases, with functional microsatellite instability. DNA sequencing revealed the close genetic relatedness to human CRCs, including a similar mutational signature, chromosomal instability, and functionally-relevant mutations affecting KRAS (G12D), TP53 (R175H, R273*), APC, AMER1, ALK, and ARID1A. Interestingly, MLH1 mutations were rarely identified on a somatic or germline level. Transcriptomics not only corroborated the similarities of rhesus and human CRCs, but also demonstrated the significant downregulation of MLH1 but not MSH2, MSH6, or PMS2 in rhesus CRCs. Methylation-specific qPCR suggested CIMP-positivity in 9/16 rhesus CRCs, but all 16/16 exhibited significant MLH1 promoter hypermethylation. DNA hypermethylation was modelled to affect DNA topology, particularly propeller twist and roll profiles. Modelling the DNA topology of a transcription factor binding motif (TFAP2A) in the MLH1 promoter that overlapped with a methylation-specific probe, we observed significant differences in DNA topology upon experimentally shown DNA methylation. This suggests a role of transcription factor binding interference in epigenetic silencing of MLH1 in rhesus CRCs. CONCLUSIONS: These data indicate that epigenetic silencing suppresses MLH1 transcription, induces the loss of MLH1 protein, abrogates mismatch repair, and drives genomic instability in naturally occurring CRC in rhesus macaques. We consider this spontaneous, uninduced CRC in immunocompetent, treatment-naïve rhesus macaques to be a uniquely informative model for human CRC.
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Neoplasias Encefálicas , Neoplasias Colorrectales , Inestabilidad de Microsatélites , Síndromes Neoplásicos Hereditarios , Humanos , Animales , Macaca mulatta/genética , Macaca mulatta/metabolismo , Homólogo 1 de la Proteína MutL/genética , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto/genética , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto/metabolismo , Neoplasias Colorrectales/patología , Metilación de ADN/genética , Epigénesis Genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , ADN/metabolismo , Reparación de la Incompatibilidad de ADN/genéticaRESUMEN
Paracoccidioidomycosis (PCM) is a systemic granulomatous mycosis prevalent in individuals who carry out rural activities. Its etiological agent is a thermodimorphic fungus belonging to the genus; Paracoccidioides spp. Seven species of this fungus are known: Paracoccidioides brasiliensis, Paracoccidioides lutzii, Paracoccidioides americana, Paracoccidioides restrepiensis, Paracoccidioides venezuelensis, Paracoccidioides loboi and Paracoccidioides ceti. For a long time, Paracoccidioides brasiliensis was attributed as the only causal agent of this mycosis. What is known about adhesins, virulence, escape mechanisms and fungal involvement with the host's immune system is correlated with the species Paracoccidioides brasiliensis. Interactions between Paracoccidioides spp. and the host are complex and dynamic. The fungus needs nutrients for its needs and must adapt to a hostile environment, evading the host's immune system, thus enabling the development of the infectious process. On the other hand, the host's immune system recognizes Paracoccidioides spp. and employs all protective mechanisms to prevent fungal growth and consequently tissue invasion. Knowing this, understanding how Paracoccidioides spp. escapes the host's immune system, can help to understand the pathogenic mechanisms related to the development of the disease and, therefore, in the design of new specific treatment strategies. In this review we discuss these mechanisms and what are the adhesion molecules of Paracoccidioides spp. uses to escape the hostile environment imposed by the host's defense mechanisms; finally, we suggest how to neutralize them with new antifungal therapies.
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Interacciones Huésped-Patógeno , Paracoccidioides , Paracoccidioidomicosis , Paracoccidioides/patogenicidad , Paracoccidioides/inmunología , Paracoccidioidomicosis/microbiología , Paracoccidioidomicosis/inmunología , Humanos , Virulencia , Evasión Inmune , AnimalesRESUMEN
PURPOSE: To assess the test-retest and inter-rater reliability of goniometry and fleximetry in measuring cervical range of motion in individuals with chronic neck pain. METHODS: A reliability study. Thirty individuals with chronic neck pain were selected. Cervical range of motion was measured by goniometry and fleximetry at two time points 7 days apart. To characterize the sample, we used the numerical pain rating scale, Pain-Related Catastrophizing Thoughts Scale, and Neck Disability Index. Intraclass correlation coefficient (ICC), standard error of measurement (SEM) and minimum detectable change (MDC) were calculated. Correlations between goniometry and fleximetry measurements were performed using Spearman's correlation coefficient (rho). RESULTS: For goniometry, we found excellent test-retest reliability (ICC ≥ 0.986, SEM ≤ 1.89%, MDC ≤ 5.23%) and inter-rater reliability (ICC ≥ 0.947, SEM ≤ 3.91%, MDC ≤ 10.84%). Similarly, we found excellent test-retest reliability (ICC ≥ 0.969, SEM ≤ 2.71%, MDC ≤ 7.52%) and inter-rater reliability (ICC ≥ 0.981, SEM ≤ 1.88%, MDC ≤ 5.20%) for fleximetry. Finally, we observed a strong correlation between the goniometry and the fleximetry for all cervical movements (rho ≥ 0.993). CONCLUSION: Goniometry and fleximetry measurements are reliable for assessing cervical range of motion in individuals with chronic neck pain.
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Artrometría Articular , Vértebras Cervicales , Dolor Crónico , Dolor de Cuello , Rango del Movimiento Articular , Humanos , Dolor de Cuello/fisiopatología , Dolor de Cuello/diagnóstico , Rango del Movimiento Articular/fisiología , Femenino , Reproducibilidad de los Resultados , Masculino , Dolor Crónico/fisiopatología , Dolor Crónico/diagnóstico , Artrometría Articular/métodos , Adulto , Persona de Mediana Edad , Vértebras Cervicales/fisiopatología , Dimensión del Dolor/métodos , Variaciones Dependientes del ObservadorRESUMEN
In Portugal, more than 98% of domestic cooking oil is disposed of improperly every day. This avoids recycling/reconverting into another energy. Is also may become a potential harmful contaminant of soil and water. Driven by the utility of recycled cooking oil, and leveraging the exponential growth of ubiquitous computing approaches, we propose an IoT smart solution for domestic used cooking oil (UCO) collection bins. We call this approach SWAN, which stands for Smart Waste Accumulation Network. It is deployed and evaluated in Portugal. It consists of a countrywide network of collection bin units, available in public areas. Two metrics are considered to evaluate the system's success: (i) user engagement, and (ii) used cooking oil collection efficiency. The presented system should (i) perform under scenarios of temporary communication network failures, and (ii) be scalable to accommodate an ever-growing number of installed collection units. Thus, we choose a disruptive approach from the traditional cloud computing paradigm. It relies on edge node infrastructure to process, store, and act upon the locally collected data. The communication appears as a delay-tolerant task, i.e., an edge computing solution. We conduct a comparative analysis revealing the benefits of the edge computing enabled collection bin vs. a cloud computing solution. The studied period considers four years of collected data. An exponential increase in the amount of used cooking oil collected is identified, with the developed solution being responsible for surpassing the national collection totals of previous years. During the same period, we also improved the collection process as we were able to more accurately estimate the optimal collection and system's maintenance intervals.
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OBJECTIVES: Evaluate the impact of ABO histo-blood group type on COVID-19 severity. BACKGROUND: ABO histo-blood type has been associated with different outcomes in infectious diseases. It has also shown a higher proportion of type A patients with SARS-CoV-2. In this observational study, extracted from an ongoing clinical trial on the efficacy of convalescent plasma transfused in COVID-19 patients, we describe the impact of ABO blood type on the risk of developing severe COVID-19. MATERIALS AND METHODS: Seventy-two consecutive patients (37 type A, 23 type O, 11 type B, 1 type AB) with severe (respiratory failure) COVID-19 were included. Control group was composed of 160 individuals randomly selected from the same populational basis. RESULTS: Blood group A was overrepresented (51.39%) in the patient group in relation to the control group (30%), whereas blood group O was less represented (31.94%) in patient than in control group (48%). Odds ratio (A vs. O) was 2.581 (1.381-4.817), CI 95%; p = 0.004. Also, blood group A patients appeared to have more severe disease, given by the scores of the Sequential Organ Failure Assessment and Simplified Acute Physiologic Score 3 (p = 0.036 and p = 0.058, respectively). CONCLUSION: Histo-blood type A is associated with a higher risk of developing severe COVID-19 in relation to blood type O.
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COVID-19 , Sistema del Grupo Sanguíneo ABO , COVID-19/terapia , Humanos , Inmunización Pasiva , Factores de Riesgo , SARS-CoV-2 , Sueroterapia para COVID-19RESUMEN
In the last years, "omics" approaches have been applied to study the toxicity of nanomaterials (NM) with the aim of obtaining insightful information on their biological effects. One of the most developed "omics" field, transcriptomics, expects to find unique profiles of differentially-expressed genes after exposure to NM that, besides providing evidence of their mechanistic mode of action, may also be used as biomarkers for biomonitoring purposes. Moreover, several NM have been associated with epigenetic alterations, i.e., changes in the regulation of gene expression caused by differential DNA methylation, histone tail modification and microRNA expression. Epigenomics research focusing on DNA methylation is increasingly common and the role of microRNAs is being better understood, either promoting or suppressing biological pathways. Moreover, the proteome is a highly dynamic system that changes constantly in response to a stimulus. Therefore, proteomics can identify changes in protein abundance and/or variability that lead to a better understanding of the underlying mechanisms of action of NM while discovering biomarkers. As to genomics, it is still not well developed in nanotoxicology. Nevertheless, the individual susceptibility to NM mediated by constitutive or acquired genomic variants represents an important component in understanding the variations in the biological response to NM exposure and, consequently, a key factor to evaluate possible adverse effects in exposed individuals. By elucidating the molecular changes that are involved NM toxicity, the new "omics" studies are expected to contribute to exclude or reduce the handling of hazardous NM in the workplace and support the implementation of regulation to protect human health.
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Epigenómica , Proteómica , Biomarcadores , Genómica , Humanos , ProteomaRESUMEN
Morphological characteristics of pequi fruits (Caryocar brasiliense) allows us to obtain information for the conservation, breeding, and detect genetic variability. Thus, the aims of this research were to characterize the genetic diversity of Caryocar brasiliense that produce fruits with and without thorn at the endocarp; determine the important characters in the study of genetic diversity, and to estimate phenotypic and genotypic correlations. 80 fruits with thorns and 90 fruits without thorns were evaluated. Data were used for analysis: Euclidian distance as a measure of dissimilarity and the Tocher method for delimitation of groups; Principal Component Analysis, and genotypic and phenotypic correlations. Genetic dissimilarity of C. brasiliense ranged from 0.066 (B6-D6) to 0.908 (A14-B3). Tocher method allowed dividing the matrices into three groups, the dendrogram into five groups, and the principal components allowed the distribution in 8 groups. We observed 15 significant correlations for characters of fruit with thorns and 31 correlations for characters of fruit without thorns. The weight of the fruit (with thorns) and the pyrene yield (without thorns) are relevant correlations for production. The groupings generated allowed the classification of the matrices into distinct sets. Allowed the identification of potential producers plants that could be used in breeding programs.
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Ericales , Frutas , Frutas/genética , Variación Genética/genética , FitomejoramientoRESUMEN
Samanea tubulosa Benth. it has been widely used in traditional medicine to treat inflammatory processes. The present study aimed to investigate the antinociceptive effect and mechanism of action of the fractions obtained from the Samanea tubulosa pods in mice. The antinociceptive activity was evaluated in formalin, capsaicin and glutamate tests and the. The possible mechanisms of action involved in the antinociceptive effect of the hexane and ethyl acetate fraction in the opioid system, also the the K + ATP channels and the L-arigine pathways of nitric oxide were evaluated. The chemical characterization analysis revealed in the hexane fraction the presence of triterpenes such as lupenone and lupeol. In the glutamate test, the hexane and ethyl acetate fractions showed antinociceptive activity at the dose of 12.5 and 25 mg kg-1. The antinociception produced by the hexane and ethyl acetate fractions was significantly reversed by naloxone, indicating that the fractions act through the opioid pathway. Antinociceptive response of the ethyl acetate fraction was blocked by glibenclamide, indicating that this fraction acts via the K + ATP channels activation. It is concluded that the fractions under study exert antinociceptive activity possibly related to the opioid route and through K+ ATP channels activation.
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Dolor Agudo , Fabaceae , Dolor Agudo/tratamiento farmacológico , Adenosina Trifosfato , Analgésicos/farmacología , Analgésicos/uso terapéutico , Analgésicos Opioides , Animales , Fabaceae/metabolismo , Ácido Glutámico , Hexanos , RatonesRESUMEN
BACKGROUND: Breast cancer (BC) is the most common cancer in women. In contrast, male BC is about 100 times less common than in women, being considered a rare disease. Male BC may be a distinctive subtype of BC and available data seems to indicate that male BC has a higher dependence on genetic variants than female BC. Nevertheless, the same prognostic and predictive markers are used to determine optimal management strategies for both male and female BC. Several studies have assessed the role of genetic polymorphisms (SNPs) in DNA repair genes in female BC susceptibility. However, data on male BC is scarce. Thus, the current study aimed to assess the role of SNPs in XRCC1, MUTYH and TP53 genes in a male cohort of BC, and, in addition, compare the male data with matched results previously genotyped in female BC patients. METHODS: The male BC cohort was genotyped through Real-Time PCR using TaqMan Assays for several SNPs previously analysed in Portuguese female BC patients. RESULTS: The results obtained indicate significant differences in BC susceptibility between males and females for the XRCC1 rs1799782, MUTYH rs3219489 and TP53 rs1042522 and rs8064946 variants. CONCLUSIONS: In males, XRCC1 and TP53 variants, when in heterozygosity, seem to be related with lower susceptibility for BC, contrasting with higher susceptibility for a MUTYH variant in females. These findings may help to explain the difference in incidence of BC between the two sexes.
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Neoplasias de la Mama Masculina/genética , ADN Glicosilasas/genética , Proteína p53 Supresora de Tumor/genética , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X/genética , Neoplasias de la Mama , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Polimorfismo de Nucleótido SimpleRESUMEN
A number of human biomonitoring (HBM) studies have presented data on exposure to hexavalent chromium [Cr(VI)] and cadmium (Cd), but comparatively few include results on effect biomarkers. The latter are needed to identify associations between exposure and adverse outcomes (AOs) in order to assess public health implications. To support improved derivation of EU regulation and policy making, it is of great importance to identify the most reliable effect biomarkers for these heavy metals that can be used in HBM studies. In the framework of the Human Biomonitoring for Europe (HBM4EU) initiative, our study aim was to identify effect biomarkers linking Cr(VI) and Cd exposure to selected AOs including cancer, immunotoxicity, oxidative stress, and omics/epigenetics. A comprehensive PubMed search identified recent HBM studies, in which effect biomarkers were examined. Validity and applicability of the markers in HBM studies are discussed. The most frequently analysed effect biomarkers regarding Cr(VI) exposure and its association with cancer were those indicating oxidative stress (e.g., 8-hydroxy-2'-deoxyguanosine (8-OHdG), malondialdehyde (MDA), glutathione (GSH)) and DNA or chromosomal damage (comet and micronucleus assays). With respect to Cd and to some extent Cr, ß-2-microglobulin (B2-MG) and N-acetyl-ß-D-glucosaminidase (NAG) are well-established, sensitive, and the most common effect biomarkers to relate Cd or Cr exposure to renal tubular dysfunction. Neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule (KIM)-1 could serve as sensitive biomarkers of acute kidney injury in response to both metals, but need further investigation in HBM studies. Omics-based biomarkers, i.e., changes in the (epi-)genome, transcriptome, proteome, and metabolome associated with Cr and/or Cd exposure, are promising effect biomarkers, but more HBM data are needed to confirm their significance. The combination of established effect markers and omics biomarkers may represent the strongest approach, especially if based on knowledge of mechanistic principles. To this aim, also mechanistic data were collected to provide guidance on the use of more sensitive and specific effect biomarkers. This also led to the identification of knowledge gaps relevant to the direction of future research.
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Monitoreo Biológico , Cadmio , Biomarcadores , Cadmio/toxicidad , Cromo/toxicidad , Europa (Continente) , HumanosRESUMEN
Transcatheter aortic valve implantation (TAVI) is an increasingly widespread procedure. Although this intervention is indicated for high and low surgical risk patients, some issues still remain, such as prosthesis positioning optimization in the aortic annulus. Coaxial positioning of the percutaneous prosthesis influences directly on the aortic wall stress map. The determination of the mechanical stress that acts on the vascular endothelium resulting from blood flow can be considered an important task, since TAVI positioning can lead to unfavorable hemodynamic patterns, resulting in changes in parietal stress, such as those found in post-stenotic dilatation region. This research aims to investigate the influence of the prosthetic valve inclination angle in the mechanical stresses acting in the ascending aortic wall. Aortic compliance and blood flow during cardiac cycle were numerically obtained using fluid structure interaction. The aortic model was developed through segmentation of a computed tomography image of a specific patient submitted to TAVI. When compared to standard position (coaxiality match between the prosthesis and the aortic annulus), the inclination of 4° directed to the left main coronary artery decreased the aortic wall area with high values of wall shear stress and pressure. Coaxial positioning optimization of percutaneous aortic prosthesis may decrease the high mechanical stress area. These changes may be important to reduce the aortic remodeling process, vascular calcification or even the prosthesis half-life. Computational fluid dynamics makes room for personalized medicine, with manufactured prosthesis tailored to each patient.
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Aorta/diagnóstico por imagen , Aorta/fisiología , Válvula Aórtica/cirugía , Hemodinámica , Estrés Mecánico , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Válvula Aórtica/diagnóstico por imagen , Velocidad del Flujo Sanguíneo/fisiología , Simulación por Computador , Humanos , Modelos Cardiovasculares , Tomografía Computarizada por Rayos XRESUMEN
We report on the design of a low-profile integrated millimeter-wave antenna for efficient and broadband circularly polarized electromagnetic radiation. The designed antenna comprises a chiral dielectric metasurface built with a 2×2 arrangement of dielectric cylinders with slanted-slots at the center. A broadbeam high-gain with wide axial ratio (AR)<3 dB bandwidth was reached by pairing the electric and magnetic resonances of the dielectric cylinders and the slanted slots when excited by an elliptically polarized driven-patch antenna. This electric-magnetic pairing can be tuned by varying the cylinders diameter and the tilting and rotation angles of the slanted slots. The simulation results indicate impedance-matching bandwidths up to 22.6% (25.3-31.6 GHz) with 3-dB AR bandwidths of 11.6% (26.9-30.2 GHz), which in terms of compactness (0.95λ0×0.95λ0) and performance are superior to previous antenna designs. Since the simulations were performed by assuming materials and geometries easily implementable experimentally, it is hoped that circularly polarized antennas based on chiral metasurfaces can be integrated into 5G and satellite communications.
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From the beginning of the year 2020, the world was affected by a coronavirus disease (COVID-19) pandemic, caused by SARS-CoV-2, leading to a shortage of personal protective equipment (PPE) at a global level, and thus generating exposure of health professionals to this extremely contagious virus. Within this context, the present work seeks to present an alternative for the production of face shields "face shields," in which it recommends its production "in house" through 3D printing, in principle initiated by Prusa Research, where we download your project of support of facial protectors, proceeding with printing through the 3D printer Gtmax3D Core H5. The authors produced a face shield in ABS, in a total time of 3 hours and 44 minutes. Thus, the model presented proved to be feasible, at a low cost, adding to the list of possibilities to produce inputs necessary to maintain the fight against this epidemic.
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Betacoronavirus , Infecciones por Coronavirus/prevención & control , Pandemias/prevención & control , Equipo de Protección Personal , Neumonía Viral/prevención & control , Impresión Tridimensional , COVID-19 , Humanos , Equipo de Protección Personal/provisión & distribución , SARS-CoV-2 , Flujo de TrabajoRESUMEN
Cancer drug resistance (CDR) is a major problem in therapeutic failure. Over 90% of patients with metastatic cancer present CDR. Several mechanisms underlie CDR, including the increased expression of efflux ABC transporters and epigenetic phenomena. Nevertheless, a topic that is not usually addressed is the mechanism underlying the loss of CDR once the challenge to these cells is withdrawn. A KCR cell line (doxorubicin-resistant, expressing ABCB1) was used to induce loss of resistance by withdrawing doxorubicin in culture medium. ABCB1 activity was analysed by fluorescence microscopy and flow cytometry through substrate (DiOC2) retention assays. The expression of 1008 microRNAs was assessed before and after doxorubicin withdrawal. After 16 weeks of doxorubicin withdrawal, a decrease of ABCB1 activity and expression occurred. Moreover, we determined a signature of 23 microRNAs, 13 underexpressed and 10 overexpressed, as a tool to assess loss of resistance. Through pathway enrichment analysis, "Pathways in cancer", "Proteoglycans in cancer" and "ECM-receptor interaction" were identified as relevant in the loss of CDR. Taken together, the data reinforce the assumption that ABCB1 plays a major role in the kinetics of CDR, and their levels of expression are in the dependence of the circuitry of cell miRNAs.
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Transportadoras de Casetes de Unión a ATP/genética , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Transporte Biológico , Línea Celular Tumoral , Supervivencia Celular/genética , Biología Computacional/métodos , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Perfilación de la Expresión Génica , Humanos , Cinética , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Interferencia de ARN , ARN Mensajero/genéticaRESUMEN
The EU human biomonitoring initiative, HBM4EU, aims to co-ordinate and advance human biomonitoring (HBM) across Europe. Within its remit, the project is gathering new, policy relevant, EU-wide data on occupational exposure to relevant priority chemicals and developing new approaches for occupational biomonitoring. In this manuscript, the hexavalent chromium [Cr(VI)] study design is presented as the first example of this HBM4EU approach. This study involves eight European countries and plans to recruit 400 workers performing Cr(VI) surface treatment e.g. electroplating or stainless steel welding activities. The aim is to collect new data on current occupational exposure to Cr(VI) in Europe and to test new methods for Cr biomonitoring, specifically the analysis of Cr(VI) in exhaled breath condensate (EBC) and Cr in red blood cells (RBC) in addition to traditional urinary total Cr analyses. Furthermore, exposure data will be complemented with early biological effects data, including genetic and epigenetic effects. Personal air samples and wipe samples are collected in parallel to help informing the biomonitoring results. We present standard operational procedures (SOPs) to support the harmonized methodologies for the collection of occupational hygiene and HBM samples in different countries.
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Contaminantes Ocupacionales del Aire , Cromo , Exposición Profesional , Monitoreo Biológico , Monitoreo del Ambiente , Europa (Continente) , HumanosRESUMEN
Amphidinolides are cytotoxic macrolides produced by symbiotic unicellular microalgae of the genus Amphidinium. Here we describe the identification of four related molecules belonging to this macrolide family isolated from the invertebrate Stragulum bicolor. The new molecules, named amphidinolide PX1-PX3 and stragulin A (1â»4), show an unprecedented carbon skeleton whose complete stereochemistry has been determined by spectroscopic and computational methods. Differences in the structures of these molecules modulate their biological activity in a panel of tumor cell lines, but the opened derivative stragulin (4) shows a very potent and specific cytotoxic activity (IC50 0.18 µM) against the aggressive human melanoma cell A2058.
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Antozoos/parasitología , Antibióticos Antineoplásicos/farmacología , Organismos Acuáticos/química , Dinoflagelados/química , Macrólidos/farmacología , Animales , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/aislamiento & purificación , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Concentración 50 Inhibidora , Macrólidos/química , Macrólidos/aislamiento & purificación , Estructura MolecularRESUMEN
Monitoring vectors is relevant to ascertain transmission of lymphatic filariasis (LF). This may require the best sampling method that can capture high numbers of specific species to give indication of transmission. Gravid anophelines are good indicators for assessing transmission due to close contact with humans through blood meals. This study compared the efficiency of an Anopheles gravid trap (AGT) with other mosquito collection methods including the box and the Centres for Disease Control and Prevention gravid, light, exit and BioGent-sentinel traps, indoor resting collection (IRC) and pyrethrum spray catches across two endemic regions of Ghana. The AGT showed high trapping efficiency by collecting the highest mean number of anophelines per night in the Western (4.6) and Northern (7.3) regions compared with the outdoor collection methods. Additionally, IRC was similarly efficient in the Northern region (8.9) where vectors exhibit a high degree of endophily. AGT also showed good trapping potential for collecting Anopheles melas which is usually difficult to catch with existing methods. Screening of mosquitoes for infection showed a 0.80-3.01% Wuchereria bancrofti and 2.15-3.27% Plasmodium spp. in Anopheles gambiae. The AGT has shown to be appropriate for surveying Anopheles populations and can be useful for xenomonitoring for both LF and malaria.
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Anopheles/parasitología , Entomología/métodos , Control de Mosquitos/métodos , Mosquitos Vectores/parasitología , Plasmodium/aislamiento & purificación , Wuchereria bancrofti/aislamiento & purificación , Animales , Filariasis Linfática/transmisión , Enfermedades Endémicas , Entomología/instrumentación , Femenino , Ghana , Control de Mosquitos/instrumentaciónRESUMEN
Rhodnius prolixus not only has served as a model organism for the study of insect physiology, but also is a major vector of Chagas disease, an illness that affects approximately seven million people worldwide. We sequenced the genome of R. prolixus, generated assembled sequences covering 95% of the genome (â¼ 702 Mb), including 15,456 putative protein-coding genes, and completed comprehensive genomic analyses of this obligate blood-feeding insect. Although immune-deficiency (IMD)-mediated immune responses were observed, R. prolixus putatively lacks key components of the IMD pathway, suggesting a reorganization of the canonical immune signaling network. Although both Toll and IMD effectors controlled intestinal microbiota, neither affected Trypanosoma cruzi, the causal agent of Chagas disease, implying the existence of evasion or tolerance mechanisms. R. prolixus has experienced an extensive loss of selenoprotein genes, with its repertoire reduced to only two proteins, one of which is a selenocysteine-based glutathione peroxidase, the first found in insects. The genome contained actively transcribed, horizontally transferred genes from Wolbachia sp., which showed evidence of codon use evolution toward the insect use pattern. Comparative protein analyses revealed many lineage-specific expansions and putative gene absences in R. prolixus, including tandem expansions of genes related to chemoreception, feeding, and digestion that possibly contributed to the evolution of a blood-feeding lifestyle. The genome assembly and these associated analyses provide critical information on the physiology and evolution of this important vector species and should be instrumental for the development of innovative disease control methods.
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Adaptación Fisiológica/genética , Enfermedad de Chagas , Interacciones Huésped-Parásitos/genética , Insectos Vectores , Rhodnius , Trypanosoma cruzi/fisiología , Animales , Secuencia de Bases , Transferencia de Gen Horizontal , Humanos , Insectos Vectores/genética , Insectos Vectores/parasitología , Datos de Secuencia Molecular , Rhodnius/genética , Rhodnius/parasitología , Wolbachia/genéticaRESUMEN
The N-salicyloyltryptamine (NST) is an indole derivative compound analogue to the alkaloid N-benzoyltryptamine. In the present study, the antiedematogenic activity of NST was investigated in animal models. Firstly, the acute toxicity for NST was assessed according to the OECD Guideline no. 423. The potential NST-induced antiedematogenic activity was evaluated by carrageenan-induced paw edema in rats, as well as by dextran-, compound 48/80-, histamine-, serotonin-, capsaicine-, and prostaglandin E2-induced paw edema in mice. The effect of NST on compound 48/80-induced ex vivo mast cell degranulation on mice mesenteric bed was investigated. No death or alteration of behavioral parameters was observed after administration of NST (2000 mg/kg, i.p.) during the observation time of 14 days. The NST (100 and 200 mg/kg, i.p.) inhibited the carrageenan-induced edema from the 1st to the 5th hour (**p<0.01; ***p<0.001). The edematogenic activity induced by dextran, compound 48/80, histamine, serotonin, capsaicin, and prostaglandin E2 was inhibited by NST (100 mg/kg, i.p.) throughout the observation period (**p<0.01; ***p<0.001). The pretreatment with NST (50, 100 or 200 mg/kg, i.p) attenuates the compound 48/80-induced mast cell degranulation (**p<0.01; ***p<0.001). Thus, the inhibition of both mast cell degranulation and release of endogenous mediators are probably involved in the NST-induced antiedematogenic effect.