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1.
Trends Genet ; 39(7): 545-559, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36801111

RESUMEN

The availability of public genomic resources can greatly assist biodiversity assessment, conservation, and restoration efforts by providing evidence for scientifically informed management decisions. Here we survey the main approaches and applications in biodiversity and conservation genomics, considering practical factors, such as cost, time, prerequisite skills, and current shortcomings of applications. Most approaches perform best in combination with reference genomes from the target species or closely related species. We review case studies to illustrate how reference genomes can facilitate biodiversity research and conservation across the tree of life. We conclude that the time is ripe to view reference genomes as fundamental resources and to integrate their use as a best practice in conservation genomics.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Genómica , Genoma
2.
BMC Oral Health ; 24(1): 641, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816807

RESUMEN

BACKGROUND: Different processing techniques are employed to obtain poly (methyl methacrylate) (PMMA) with consistent surface quality in terms of topography and tribological function. The purpose of this research is to evaluate its influence on the surface height distribution. METHODS: In this research, samples of conventional and CAD/CAM acrylic resins were prepared. The following surface roughness parameters were extracted from the profilometric readings: arithmetic mean roughness (Pa), skewness (Psk) and kurtosis (Pku). Profilometric profiles were additionally obtained. RESULTS: The average roughness (Pa) with the conventional technique was significantly higher compared to CAD/CAM (t = 4.595; P < 0.001). Heat-cured resins presented the highest mean Pa (F = 6.975; P = 0.06). Heat-cured and milled resins show lower coefficient variation (CV) values, indicating more consistent surface finishing. The surface profiles revealed distinct characteristics in terms of skewness and kurtosis. CONCLUSIONS: The surface processing method, chemical composition and resin type significantly influence the surface finishing of the resin. The CAD/CAM resins exhibited superior results in terms of surface arithmetic mean roughness (Pa). However, heat-cured resin revealed to present the better surface consistency.


Asunto(s)
Resinas Acrílicas , Diseño Asistido por Computadora , Ensayo de Materiales , Polimetil Metacrilato , Propiedades de Superficie , Resinas Acrílicas/química , Polimetil Metacrilato/química , Materiales Dentales/química , Humanos , Calor
3.
Endoscopy ; 55(3): 235-244, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35863354

RESUMEN

BACKGROUND : Endoscopic submucosal dissection (ESD) in colorectal lesions is technically demanding and a significant rate of noncurative procedures is expected. We aimed to assess the rate of residual lesions after a noncurative ESD for colorectal cancer (CRC) and to establish predictive scores to be applied in the clinical setting. METHODS : Retrospective multicenter analysis of consecutive colorectal ESDs. Patients with noncurative ESDs performed for the treatment of CRC lesions submitted to complementary surgery or with at least one follow-up endoscopy were included. RESULTS : From 2255 colorectal ESDs, 381 (17 %) were noncurative, and 135 of these were performed in CRC lesions. A residual lesion was observed in 24 patients (18 %). Surgery was performed in 96 patients and 76 (79 %) had no residual lesion in the colorectal wall or in the lymph nodes. The residual lesion rate for sm1 cancers was 0 %, and for > sm1 cancers was also 0 % if no other risk factors were present. Independent risk factors for lymph node metastasis were poor differentiation and lymphatic permeation (NC-Lymph score). Risk factors for the presence of a residual lesion in the wall were piecemeal resection, poor differentiation, and positive/indeterminate vertical margin (NC-Wall score). CONCLUSIONS : Lymphatic permeation or poor differentiation warrant surgery owing to their high risk of lymph node metastasis, mainly in > sm1 cancers. In the remaining cases, en bloc and R0 resections resulted in a low risk of residual lesions in the wall. Our scores can be a useful tool for the management of patients who undergo noncurative colorectal ESDs.


Asunto(s)
Neoplasias Colorrectales , Resección Endoscópica de la Mucosa , Humanos , Resección Endoscópica de la Mucosa/efectos adversos , Resección Endoscópica de la Mucosa/métodos , Metástasis Linfática , Endoscopía , Estudios Retrospectivos , Neoplasia Residual , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/patología , Resultado del Tratamiento
4.
J Toxicol Environ Health A ; : 1-10, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37185102

RESUMEN

Chloramine T, a sodium p-toluene sulfonchloramide, is known to possess a wide spectrum of biocidal activity and is employed as a disinfectant in fish farms to treat bacterial infections. Although Chloramine T may effectively combat pathogens, the sublethal and lethal effects and changes in acetylcholinesterase (AChE) activity remain poorly elucidated using Danio rerio (zebrafish) embryos. Zebrafish is considered a model organism for toxicant screening research and exhibits mammalian-like physiological responses when exposed to environmental pollutants. The aim of this study was to (1) determine LC50 of Chloramine T after 96 hr exposure, (2) verify disinfectant effects on developmental morphology, and (3) evaluate the disinfectant effects on AChE activity in zebrafish embryos. Chloramine T exposure was performed using 16, 32, 64, 128, or 256 mg/L concentrations. The mortality LC50 values were 143.05 ± 3.11 and 130.97 ± 7.4 mg/L at 24 and 96 hr, respectively. Data demonstrated delayed hatching, reduced heartbeats, cardiac edema, and equilibrium disruption of hatched larvae throughout embryonic development. In addition, Chloramine T inhibited AChE activity at 64 or 128 mg/L after 96 hr treatment, corroborating the sub-lethality results observed in zebrafish embryo development and demonstrating an equilibrium disruption in zebrafish larvae.

5.
Am J Primatol ; 85(1): e23453, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36468411

RESUMEN

In tropical forests, anthropogenic activities are major drivers of the destruction and degradation of natural habitats, causing severe biodiversity loss. African colobine monkeys (Colobinae) are mainly folivore and strictly arboreal primates that require large forests to subsist, being among the most vulnerable of all nonhuman primates. The Western red colobus Piliocolobus badius and the King colobus Colobus polykomos inhabit highly fragmented West African forests, including the Cantanhez Forests National Park (CFNP) in Guinea-Bissau. Both species are also found in the largest and best-preserved West African forest-the Taï National Park (TNP) in Ivory Coast. Colobine monkeys are hunted for bushmeat in both protected areas, but these exhibit contrasting levels of forest fragmentation, thus offering an excellent opportunity to investigate the importance of well-preserved forests for the maintenance of evolutionary potential in these arboreal primates. We estimated genetic diversity, population structure, and demographic history by using microsatellite loci and mitochondrial DNA. We then compared the genetic patterns of the colobines from TNP with the ones previously obtained for CFNP and found contrasting genetic patterns. Contrary to the colobines from CFNP that showed very low genetic diversity and a strong population decline, the populations in TNP still maintain high levels of genetic diversity and we found no clear signal of population decrease in Western red colobus and a limited decrease in King colobus. These results suggest larger and historically more stable populations in TNP compared to CFNP. We cannot exclude the possibility that the demographic effects resulting from the recent increase of bushmeat hunting are not yet detectable in TNP using genetic data. Nevertheless, the fact that the TNP colobus populations are highly genetically diverse and maintain large effective population sizes suggests that well-preserved forests are crucial for the maintenance of populations, species, and probably for the evolutionary potential in colobines.


Asunto(s)
Colobinae , Colobus , Animales , Colobus/genética , Colobinae/genética , Bosques , Evolución Biológica , Árboles
6.
Conserv Genet ; 24(1): 125-136, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36694805

RESUMEN

There are only about 7,100 adolescent and adult cheetahs (Acinonyx jubatus) remaining in the wild. With the majority occurring outside protected areas, their numbers are rapidly declining. Evidence-based conservation measures are essential for the survival of this species. Genetic data is routinely used to inform conservation strategies, e.g., by establishing conservation units (CU). A commonly used marker in conservation genetics is mitochondrial DNA (mtDNA). Here, we investigated the cheetah's phylogeography using a large-scale mtDNA data set to refine subspecies distributions and better assign individuals to CUs. Our dataset mostly consisted of historic samples to cover the cheetah's whole range as the species has been extinct in most of its former distribution. While our genetic data largely agree with geography-based subspecies assignments, several geographic regions show conflicting mtDNA signals. Our analyses support previous findings that evolutionary forces such as incomplete lineage sorting or mitochondrial capture likely confound the mitochondrial phylogeography of this species, especially in East and, to some extent, in Northeast Africa. We caution that subspecies assignments solely based on mtDNA should be treated carefully and argue for an additional standardized nuclear single nucleotide polymorphism (SNP) marker set for subspecies identification and monitoring. However, the detection of the A. j. soemmeringii specific haplogroup by a newly designed Amplification-Refractory Mutation System (ARMS) can already provide support for conservation measures. Supplementary Information: The online version contains supplementary material available at 10.1007/s10592-022-01483-1.

7.
Int J Mol Sci ; 24(19)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37834233

RESUMEN

Single-particle cryo-electron microscopy (cryo-EM SPA) has recently emerged as an exceptionally well-suited technique for determining the structure of membrane proteins (MPs). Indeed, in recent years, huge increase in the number of MPs solved via cryo-EM SPA at a resolution better than 3.0 Å in the Protein Data Bank (PDB) has been observed. However, sample preparation remains a significant challenge in the field. Here, we evaluated the MPs solved using cryo-EM SPA deposited in the PDB in the last two years at a resolution below 3.0 Å. The most critical parameters for sample preparation are as follows: (i) the surfactant used for protein extraction from the membrane, (ii) the surfactant, amphiphiles, nanodiscs or other molecules present in the vitrification step, (iii) the vitrification method employed, and (iv) the type of grids used. The aim is not to provide a definitive answer on the optimal sample conditions for cryo-EM SPA of MPs but rather assess the current trends in the MP structural biology community towards obtaining high-resolution cryo-EM structures.


Asunto(s)
Proteínas de la Membrana , Manejo de Especímenes , Proteínas de la Membrana/química , Microscopía por Crioelectrón/métodos , Manejo de Especímenes/métodos , Imagen Individual de Molécula , Tensoactivos
8.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38203676

RESUMEN

Antibacterial resistance poses a critical public health threat, challenging the prevention and treatment of bacterial infections. The search for innovative antibacterial agents has spurred significant interest in quaternary heteronium salts (QHSs), such as quaternary ammonium and phosphonium compounds as potential candidates. In this study, a library of 49 structurally related QHSs was synthesized, varying the cation type and alkyl chain length. Their antibacterial activities against Staphylococcus aureus, including antibiotic-resistant strains, were evaluated by determining minimum inhibitory/bactericidal concentrations (MIC/MBC) ≤ 64 µg/mL. Structure-activity relationship analyses highlighted alkyl-triphenylphosphonium and alkyl-methylimidazolium salts as the most effective against S. aureus CECT 976. The length of the alkyl side chain significantly influenced the antibacterial activity, with optimal chain lengths observed between C10 and C14. Dose-response relationships were assessed for selected QHSs, showing dose-dependent antibacterial activity following a non-linear pattern. Survival curves indicated effective eradication of S. aureus CECT 976 by QHSs at low concentrations, particularly compounds 1e, 3e, and 5e. Moreover, in vitro human cellular data indicated that compounds 2e, 4e, and 5e showed favourable safety profiles at concentrations ≤ 2 µg/mL. These findings highlight the potential of these QHSs as effective agents against susceptible and resistant bacterial strains, providing valuable insights for the rational design of bioactive QHSs.


Asunto(s)
Compuestos de Amonio , Staphylococcus aureus Resistente a Meticilina , Compuestos Organofosforados , Compuestos de Amonio Cuaternario , Infecciones Estafilocócicas , Humanos , Sales (Química)/farmacología , Staphylococcus aureus , Antibacterianos/farmacología , Cationes/farmacología
9.
Mol Ecol ; 31(16): 4208-4223, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35748392

RESUMEN

We live in a world characterized by biodiversity loss and global environmental change. The extinction of large carnivores can have ramifying effects on ecosystems like an uncontrolled increase in wild herbivores, which in turn can have knock-on impacts on vegetation regeneration and communities. Cheetahs (Acinonyx jubatus) serve important ecosystem functions as apex predators; yet, they are quickly heading towards an uncertain future. Threatened by habitat loss, human-wildlife conflict and illegal trafficking, there are only approximately 7100 individuals remaining in nature. We present the most comprehensive genome-wide analysis of cheetah phylogeography and conservation genomics to date, assembling samples from nearly the entire current and past species' range. We show that their phylogeography is more complex than previously thought, and that East African cheetahs (A. j. raineyi) are genetically distinct from Southern African individuals (A. j. jubatus), warranting their recognition as a distinct subspecies. We found strong genetic differentiation between all classically recognized subspecies, thus refuting earlier findings that cheetahs show only little differentiation. The strongest differentiation was observed between the Asiatic and all the African subspecies. We detected high inbreeding in the Critically Endangered Iranian (A. j. venaticus) and North-western (A. j. hecki) subspecies, and show that overall cheetahs, along with snow leopards, have the lowest genome-wide heterozygosity of all the big cats. This further emphasizes the cheetah's perilous conservation status. Our results provide novel and important information on cheetah phylogeography that can support evidence-based conservation policy decisions to help protect this species. This is especially relevant in light of ongoing and proposed translocations across subspecies boundaries, and the increasing threats of illegal trafficking.


Asunto(s)
Acinonyx , Acinonyx/genética , Animales , Ecosistema , Genoma , Genómica , Humanos , Irán
10.
Mol Ecol ; 31(3): 993-1006, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34775636

RESUMEN

Carnivores tend to exhibit a lack of (or less pronounced) genetic structure at continental scales in both a geographic and temporal sense and this can confound the identification of post-glacial colonization patterns in this group. In this study we used genome-wide data (using genotyping by sequencing [GBS]) to reconstruct the phylogeographic history of a widespread carnivore, the red fox (Vulpes vulpes), by investigating broad-scale patterns of genomic variation, differentiation and admixture amongst contemporary populations in Europe. Using 15,003 single nucleotide polymorphisms (SNPs) from 524 individuals allowed us to identify the importance of refugial regions for the red fox in terms of endemism (e.g., Iberia). In addition, we tested multiple post-glacial recolonization scenarios of previously glaciated regions during the Last Glacial Maximum using an Approximate Bayesian Computation (ABC) approach that were unresolved from previous studies. This allowed us to identify the role of admixture from multiple source population post-Younger Dryas in the case of Scandinavia and ancient land-bridges in the colonization of the British Isles. A natural colonization of Ireland was deemed more likely than an ancient human-mediated introduction as has previously been proposed and potentially points to a larger mammalian community on the island in the early post-glacial period. Using genome-wide data has allowed us to tease apart broad-scale patterns of structure and diversity in a widespread carnivore in Europe that was not evident from using more limited marker sets and provides a foundation for next-generation phylogeographic studies in other non-model species.


Asunto(s)
Zorros , Variación Genética , Animales , Teorema de Bayes , Europa (Continente) , Zorros/genética , Humanos , Filogenia , Filogeografía
11.
Gastrointest Endosc ; 95(4): 610-625.e9, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34952093

RESUMEN

BACKGROUND AND AIMS: Small-bowel capsule endoscopy (SBCE) and device-assisted enteroscopy (DAE) are essential in obscure GI bleeding (OGIB) management. However, the best timing for such procedures remains unknown. This meta-analysis aimed to compare, for the first time, diagnostic and therapeutic yields, detection of active bleeding and vascular lesions, recurrent bleeding, and mortality of "early" versus "nonearly" SBCE and DAE. METHODS: MEDLINE, ScienceDirect, and Cochrane Central Register of Controlled Trials were searched to identify studies comparing early versus nonearly SBCE and DAE. Random-effects meta-analysis was performed; reporting quality was assessed. RESULTS: From 1974 records, 39 were included (4825 patients). Time intervals for the early approach varied, within 14 days in SBCE and 72 hours in DAE. The pooled diagnostic and therapeutic yields of early DAE were superior to those of SBCE (7.97% and 20.89%, respectively; P < .05). The odds for active bleeding (odds ratio [OR], 5.09; I2 = 53%), positive diagnosis (OR, 3.99; I2 = 45%), and therapeutic intervention (OR, 3.86; I2 = 67%) were higher in the early group for SBCE and DAE (P < .01). Subgroup effects in diagnostic yield were only identified for the early group sample size. Our study failed to identify differences when studies were classified according to time intervals for early DAE (I2 < 5%), but the analysis was limited because of a lack of data availability. Lower recurrent bleeding in early SBCE and DAE was observed (OR, .40; P < .01; I2 = 0%). CONCLUSIONS: The role of small-bowel studies in the early evaluation of OGIB is unquestionable, impacting diagnosis, therapeutic intervention, and prognosis. Comparative studies are still needed to identify optimal timing.


Asunto(s)
Endoscopía Capsular , Endoscopía Capsular/métodos , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/terapia , Humanos , Intestino Delgado/patología
12.
Zygote ; 30(6): 891-894, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36148879

RESUMEN

Oxidative stress is an undesirable effect of in vitro culture, which requires antioxidant supplementation. This study investigated the analogue of resveratrol (RA33) as an alternative to resveratrol, an antioxidant molecule, for the in vitro culture of in vitro-fertilized bovine embryos. The effect of different concentrations of RA33 on embryo development was evaluated and a comparison between RA33 and resveratrol was performed. The cleavage rate was higher (P < 0.05) with 2.5 µM (69.0 ± 4.4%) than at 0, 0.1 or 0.5 µM RA33 (62.1 ± 2.0%, 60.7 ± 5.9% and 56.7 ± 5.8%, respectively). The blastocyst rates on days 7 and 8 post-fertilization with 2.5 µM RA33 (19.4 ± 3.3% and 24.6 ± 3.3%, respectively) were higher (P < 0.05) than for 0 µM (12.4 ± 2.5% and 15.2±2.5%, respectively). When 2.5 µM RA33 was compared with 0.5 µM resveratrol, similar (P > 0.05) cleavage and blastocyst rates were found between them, but the cleavage rate was higher (P < 0.05) in the control (80.8 ± 3.4%) than for the resveratrol treatment (76.4 ± 3.6%). The numbers of apoptotic cells and the apoptotic index were lower (P < 0.05) with RA33 (6.5 ± 0.6 cells and 6.4 ± 0.7%, respectively) and resveratrol (5 ± 0.8 cells and 5.5 ± 1.0%, respectively) than in the control group (9.8 ± 1.2 cells and 8.9 ± 1.1%, respectively). In conclusion, RA33 can enhance the preimplantation development of in vitro-fertilized bovine embryos and be an alternative to resveratrol in embryo culture medium.


Asunto(s)
Antioxidantes , Técnicas de Cultivo de Embriones , Bovinos , Animales , Resveratrol/farmacología , Antioxidantes/farmacología , Oocitos , Fertilización In Vitro , Blastocisto , Desarrollo Embrionario
13.
Molecules ; 27(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36234718

RESUMEN

Targeting antioxidants to mitochondria is considered a promising strategy to prevent cellular senescence and skin ageing. In this study, we investigate whether four hydroxybenzoic acid-based mitochondria-targeted antioxidants (MitoBENs, MB1-4) could be used as potential active ingredients to prevent senescence in skin cells. Firstly, we evaluated the chemical stability, cytotoxicity, genotoxicity and mitochondrial toxicity of all compounds. We followed this by testing the antioxidant protective capacity of the two less toxic compounds on human skin fibroblasts. We then assessed the effects of the best hit on senescence, inflammation and mitochondrial remodeling on a 3D skin cell model, while also testing its mutagenic potential. Cytotoxicity and mitochondrial toxicity rankings were produced: MB3 < MB4 ≃ MB1 < MB2 and MB3 < MB1 < MB4 < MB2, respectively. These results suggest that pyrogallol-based compounds (MB2 and MB4) have lower cytotoxicity. The pyrogallol derivative, MB2, containing a 6-carbon spacer, showed a more potent antioxidant protective activity against hydrogen peroxide cytotoxicity. In a 3D skin cell model, MB2 also decreased transcripts related to senescence. In sum, MB2's biological safety profile, good chemical stability and lack of mutagenicity, combined with its anti-senescence effect, converts MB2 into a good candidate for further development as an active ingredient for skin anti-ageing products.


Asunto(s)
Antioxidantes , Envejecimiento de la Piel , Antioxidantes/farmacología , Carbono , Humanos , Peróxido de Hidrógeno/farmacología , Hidroxibenzoatos/farmacología , Mitocondrias , Pirogalol
14.
J Med Virol ; 93(6): 3383-3388, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33174631

RESUMEN

Pregnant women are an important group to be monitored for infection due to the risk of transmitting infections to their babies. Both herpes simples virus (HSV) and Zika virus (ZIKV) are neurotropic viruses that can be transmitted congenitally. In this study, the prevalence and risk factors of HSV among Zika-positive and -negative pregnant women from Rio de Janeiro, Brazil, were evaluated and compared. About 167 serum samples included in our study were from pregnant women with ZIKV infection symptoms, who were attended to in different hospitals in Rio de Janeiro between November 2015 to February 2016. Blood samples collected from 167 pregnant women were used for this study. The presence of HSV antibodies and viremia were evaluated by commercial ELISA and quantitative real-time polymerase chain reaction analyses, respectively. The data obtained from medical records were statistically analyzed. The HSV-1 and HSV-2 prevalence among pregnant women was 80.2% and 12.5% for Zika-positive women and 84.5% and 5.6% for Zika-negative women, respectively. None of the pregnant women exhibited HSV viremia. Age, trimester of gestation, and skin color were associated with HSV-1 and HSV-2 prevalence among the groups studied. HSV-2 was more prevalent in Zika-positive pregnant women than in Zika-negative pregnant women, and this simultaneous infection should be better investigated in future studies.


Asunto(s)
Anticuerpos Antivirales/sangre , Herpes Simple/epidemiología , Herpes Simple/inmunología , Herpesvirus Humano 1/inmunología , Herpesvirus Humano 2/inmunología , Infección por el Virus Zika/epidemiología , Adolescente , Adulto , Brasil/epidemiología , Niño , Coinfección/sangre , Coinfección/epidemiología , Coinfección/inmunología , Coinfección/virología , Femenino , Herpes Simple/sangre , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/virología , Mujeres Embarazadas , Prevalencia , Factores de Riesgo , Estudios Seroepidemiológicos , Adulto Joven , Virus Zika/fisiología , Infección por el Virus Zika/sangre
15.
J Evol Biol ; 34(3): 537-548, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33484056

RESUMEN

The size and shape of red blood cells (RBCs) provide key information on life-history strategies in vertebrates. However, little is known about how RBC shape evolved in response to environmental factors, body size and the role of evolutionary rate. Here, we analysed RBC morphometrics in a set of Teleostei (bony fishes) and Elasmobranchii (sharks and rays) species testing the hypothesis that phylogenetic relationship explains species occupation of morphospace. We collected data on cell and nucleus area and volume, nucleus:cytoplasm ratio and shape factor for 65 species belonging to 28 orders. Then, we built phylomorphospaces separately for bony fish and sharks and rays. To test whether phylogenetic relationships predicted phenotypic similarity, we calculated multivariate phylogenetic signal. We also estimated the evolutionary rate of RBC shape for each node and tip using ridge regression. Finally, we tested whether habitat and body size influenced RBC shape using a PGLS. We found a significant phylogenetic signal in RBC shape for bony fish, but not sharks and rays. Saltwater teleost species were more clustered than freshwater ones in the phylomorphospace, suggesting clade disparity. Accordingly, the rate of evolution was highly heterogeneous, with significant decrease in Acanthopterygii. Neither habitat nor body size influenced RBC shape. In conclusion, RBC shape seems to have evolved in fishes in response to multiple selective pressures independent of life-history characters.


Asunto(s)
Evolución Biológica , Forma de la Célula , Eritrocitos/citología , Peces/sangre , Animales
16.
Sensors (Basel) ; 21(2)2021 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-33435334

RESUMEN

A transmitarray antenna is evaluated to generate a multi-focusing spot area in the Fresnel region of the antenna in the Ka-band. The antenna is designed to focus the radiated field at a certain point using a central feeding configuration. The number of feeds is increased to create as many focusing spots as feeds. The feeds are placed along an arc defined in the principal planes of the transmitarray, radiating independent near-field spots and providing a solution with a wide-angle spot scanning without an antenna displacement and a high isolation between feeds. To validate this concept, a transmitarray based on dielectric-only cells is designed and simulated under full-wave conditions. Then, this design is manufactured using a 3D printing technique, and the prototype is measured in a planar acquisition range. Measurements are performed for different feed positions in order to validate the multi-focusing capability of the antenna. Measurements and simulations show a high agreement and validate the proposed design technique.

17.
J Virol ; 94(1)2019 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-31597773

RESUMEN

The recent reemergence of yellow fever virus (YFV) in Brazil has raised serious concerns due to the rapid dissemination of the virus in the southeastern region. To better understand YFV genetic diversity and dynamics during the recent outbreak in southeastern Brazil, we generated 18 complete and nearly complete genomes from the peak of the epidemic curve from nonhuman primates (NHPs) and human infected cases across the Espírito Santo and Rio de Janeiro states. Genomic sequencing of 18 YFV genomes revealed the estimated timing, source, and likely routes of yellow fever virus transmission and dispersion during one of the largest outbreaks ever registered in Brazil. We showed that during the recent epidemic, YFV was reintroduced from Minas Gerais to the Espírito Santo and Rio de Janeiro states multiple times between 2016 and 2019. The analysis of data from portable sequencing could identify the corridor of spread of YFV. These findings reinforce the idea that continued genomic surveillance strategies can provide information on virus genetic diversity and transmission dynamics that might assist in understanding arbovirus epidemics.IMPORTANCE Arbovirus infections in Brazil, including yellow fever, dengue, zika, and chikungunya, result in considerable morbidity and mortality and are pressing public health concerns. However, our understanding of these outbreaks is hampered by the limited availability of genomic data. In this study, we investigated the genetic diversity and spatial distribution of YFV during the current outbreak by analyzing genomic data from areas in southeastern Brazil not covered by other previous studies. To gain insights into the routes of YFV introduction and dispersion, we tracked the virus by sequencing YFV genomes sampled from nonhuman primates and infected patients from the southeastern region. Our study provides an understanding of how YFV initiates transmission in new Brazilian regions and illustrates that genomics in the field can augment traditional approaches to infectious disease surveillance and control.


Asunto(s)
Brotes de Enfermedades , Genoma Viral , Fiebre Amarilla/epidemiología , Fiebre Amarilla/transmisión , Virus de la Fiebre Amarilla/genética , Aedes/virología , Alouatta/virología , Animales , Brasil/epidemiología , Callithrix/virología , Cebus/virología , Femenino , Variación Genética , Humanos , Incidencia , Leontopithecus/virología , Masculino , Mosquitos Vectores/virología , Filogenia , Filogeografía , Secuenciación Completa del Genoma , Fiebre Amarilla/virología , Virus de la Fiebre Amarilla/clasificación , Virus de la Fiebre Amarilla/aislamiento & purificación , Virus de la Fiebre Amarilla/patogenicidad
18.
Genetica ; 148(1): 25-32, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31997050

RESUMEN

Cytogenetic data showed a variation in diploid chromosome number in the genus Hyphessobrycon ranging from 2n = 46 to 52, and studies involving repetitive DNA sequences are scarce in representatives of this genus. The purpose of this paper was the chromosomal mapping of repetitive sequences (rDNA, histone genes, U snDNA and microsatellites) and investigation of the amplification of 5S rDNA clusters in the Hyphessobrycon eques genome. Two H. eques populations displayed 2n = 52 chromosomes, with the acrocentric pair No. 24 bearing Ag-NORs corresponding with CMA3+/DAPI-. FISH with a 18S rDNA probe identified the NORs on the short (p) arms of the acrocentric pairs Nos. 22 and 24. The 5S rDNA probe visualized signals on almost all chromosomes in genomes of individuals from both populations (40 signals); FISH with H3 histone probe identified two chromosome pairs, with the pericentromeric location of signals; FISH with a U2 snDNA probe identified one chromosome pair bearing signals, on the interstitial chromosomal region. The mononucleotide (A), dinucleotide (CA) and tetranucleotide (GATA) repeats were observed on the centromeric/pericentromeric and/or terminal positions of all chromosomes, while the trinucleotide (CAG) repeat showed signals on few chromosomes. Molecular analysis of 5S rDNA and non-transcribed spacers (NTS) showed microsatellites (GATA and A repeats) and a fragment of retrotransposon (SINE3/5S-Sauria) inside the sequences. This study expanded the available cytogenetic data for H. eques and demonstrated to the dispersion of the 5S rDNA sequences on almost all chromosomes.


Asunto(s)
Characidae/genética , ARN Ribosómico 5S/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Animales , Characiformes/genética , Mapeo Cromosómico/métodos , Cromosomas , ADN Ribosómico/genética , Diploidia , Femenino , Genoma/genética , Hibridación Fluorescente in Situ/métodos , Cariotipificación , Masculino , Repeticiones de Microsatélite , ARN Ribosómico 18S/genética , Especificidad de la Especie
19.
Scand J Gastroenterol ; 55(10): 1157-1162, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32772587

RESUMEN

BACKGROUND AND AIMS: DUBLIN score allows evaluation of disease activity and extent in ulcerative colitis (UC). This study aimed to evaluate DUBLIN score as a predictor of therapeutic failure as well as to associate endoscopic and histological activity scores to assess their joint performance. METHODS: Retrospective cohort study, with consecutive inclusion of patients undergoing total colonoscopy with serial biopsies between 2016 and 2019. DUBLIN score (0-9) was calculated as the product of Mayo endoscopic score (MSe 0-3) by disease extent (E1-E3). Histological activity was evaluated through Nancy score (0-4). Activity scores were correlated with biomarkers, treatment failure (therapeutic escalation, hospitalization and/or colectomy) and clinical remission at 6 months (Mayo partial score ≤ 1). RESULTS: One-hundred and seven patients were included. In 38.3% (n = 41) there was evidence of endoscopic activity (MSe ≥ 2) and in 50.5% (n = 54) histological activity (Nancy ≥ 2). MSe and DUBLIN scores showed good correlation (r = 0.943; p < .001) and both were significantly higher in patients with histological activity (p < .001). Therapeutic failure occurred in 25.2% (n = 27). MSe, DUBLIN, and Nancy scores were significantly associated with therapeutic failure (p < .001). The areas under the (AUC) ROC curve were 0.74 (MSe; p < .001), 0.78 (DUBLIN; p < .001) and 0.84 (Nancy; p < .001). Joint evaluation of endoscopic and histological activity by combining DUBLIN and Nancy scores was associated with therapeutic failure with a significantly higher AUC of 0.84 (p < .001) compared to the Dublin score alone (p = .003). CONCLUSION: Mayo and DUBLIN endoscopic scores correlated with each other and with histological activity. The joint evaluation of endoscopic and histological activity allowed to predict with greater accuracy treatment failure.


Asunto(s)
Colitis Ulcerosa , Colitis Ulcerosa/tratamiento farmacológico , Colonoscopía , Humanos , Mucosa Intestinal , Complejo de Antígeno L1 de Leucocito , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Insuficiencia del Tratamiento
20.
Sensors (Basel) ; 20(17)2020 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-32887340

RESUMEN

We produced an anatomically and dielectrically realistic phantom of the axillary region to enable the experimental assessment of Axillary Lymph Node (ALN) imaging using microwave imaging technology. We segmented a thoracic Computed Tomography (CT) scan and created a computer-aided designed file containing the anatomical configuration of the axillary region. The phantom comprises five 3D-printed parts representing the main tissues of interest of the axillary region for the purpose of microwave imaging: fat, muscle, bone, ALNs, and lung. The phantom allows the experimental assessment of multiple anatomical configurations, by including ALNs of different size, shape, and number in several locations. Except for the bone mimicking organ, which is made of solid conductive polymer, we 3D-printed cavities to represent the fat, muscle, ALN, and lung and filled them with appropriate tissue-mimicking liquids. Existing studies about complex permittivity of ALNs have reported limitations. To address these, we measured the complex permittivity of both human and animal lymph nodes using the standard open-ended coaxial-probe technique, over the 0.5 GHz-8.5 GHz frequency band, thus extending current knowledge on dielectric properties of ALNs. Lastly, we numerically evaluated the effect of the polymer which constitutes the cavities of the phantom and compared it to the realistic axillary region. The results showed a maximum difference of 7 dB at 4 GHz in the electric field magnitude coupled to the tissues and a maximum of 10 dB difference in the ALN response. Our results showed that the phantom is a good representation of the axillary region and a viable tool for pre-clinical assessment of microwave imaging technology.


Asunto(s)
Neoplasias de la Mama , Imágenes de Microonda , Fantasmas de Imagen , Axila , Neoplasias de la Mama/diagnóstico por imagen , Humanos , Ganglios Linfáticos , Tomografía Computarizada por Rayos X
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