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1.
Syst Biol ; 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38190300

RESUMEN

The opposing forces of gene flow and isolation are two major processes shaping genetic diversity. Understanding how these vary across space and time is necessary to identify the environmental features that promote diversification. The detection of considerable geographic structure in taxa from the arid Nearctic has prompted research into the drivers of isolation in the region. Several geographic features have been proposed as barriers to gene flow, including the Colorado River, Western Continental Divide, and a hypothetical Mid-Peninsular Seaway in Baja California. However, recent studies suggest that the role of barriers in genetic differentiation may have been overestimated when compared to other mechanisms of divergence. In this study, we infer historical and spatial patterns of connectivity and isolation in Desert Spiny Lizards (Sceloporus magister) and Baja Spiny Lizards (S. zosteromus), which together form a species complex composed of parapatric lineages with wide distributions in arid western North America. Our analyses incorporate mitochondrial sequences, genomic-scale data, and past and present climatic data to evaluate the nature and strength of barriers to gene flow in the region. Our approach relies on estimates of migration under the multispecies coalescent to understand the history of lineage divergence in the face of gene flow. Results show that the S. magister complex is geographically structured, but we also detect instances of gene flow. The Continental Divide is a strong barrier to gene flow, while the Colorado River is more permeable. Analyses yield conflicting results for the catalyst of differentiation of peninsular lineages in S. zosteromus. Our study shows how large-scale genomic data for thoroughly sampled species can shed new light on biogeography. Furthermore, our approach highlights the need for the combined analysis of multiple sources of evidence to adequately characterize the drivers of divergence.

2.
Bioinformatics ; 39(11)2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37988145

RESUMEN

MOTIVATION: One of the main causes hampering predictability during the model identification and automated design of gene circuits in synthetic biology is the effect of molecular noise. Stochasticity may significantly impact the dynamics and function of gene circuits, specially in bacteria and yeast due to low mRNA copy numbers. Standard stochastic simulation methods are too computationally costly in realistic scenarios to be applied to optimization-based design or parameter estimation. RESULTS: In this work, we present IDESS (Identification and automated Design of Stochastic gene circuitS), a software toolbox for optimization-based design and model identification of gene regulatory circuits in the stochastic regime. This software incorporates an efficient approximation of the Chemical Master Equation as well as a stochastic simulation algorithm-both with GPU and CPU implementations-combined with global optimization algorithms capable of solving Mixed Integer Nonlinear Programming problems. The toolbox efficiently addresses two types of problems relevant in systems and synthetic biology: the automated design of stochastic synthetic gene circuits, and the parameter estimation for model identification of stochastic gene regulatory networks. AVAILABILITY AND IMPLEMENTATION: IDESS runs under the MATLAB environment and it is available under GPLv3 license at https://doi.org/10.5281/zenodo.7788692.


Asunto(s)
Redes Reguladoras de Genes , Programas Informáticos , Simulación por Computador , Algoritmos , Biología Sintética , Procesos Estocásticos
3.
PLoS Biol ; 19(6): e3001210, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34061821

RESUMEN

Global biodiversity loss is a profound consequence of human activity. Disturbingly, biodiversity loss is greater than realized because of the unknown number of undocumented species. Conservation fundamentally relies on taxonomic recognition of species, but only a fraction of biodiversity is described. Here, we provide a new quantitative approach for prioritizing rigorous taxonomic research for conservation. We implement this approach in a highly diverse vertebrate group-Australian lizards and snakes. Of 870 species assessed, we identified 282 (32.4%) with taxonomic uncertainty, of which 17.6% likely comprise undescribed species of conservation concern. We identify 24 species in need of immediate taxonomic attention to facilitate conservation. Using a broadly applicable return-on-investment framework, we demonstrate the importance of prioritizing the fundamental work of identifying species before they are lost.


Asunto(s)
Biodiversidad , Clasificación , Investigación , Animales , Australia , Lagartos/clasificación , Serpientes/clasificación
4.
Environ Res ; 258: 119371, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38876420

RESUMEN

Cu2ZnSnS4 (CZTS) was synthesized following hot injection method and the process was optimized by varying temperature conditions. Four samples at different temperatures viz., 200, 250, 300 and 350 °C were prepared and analyzed using different characterization techniques. Based on the correlation between XRD, Raman and XPS, we conclude that the formation of ZnS and SnS2 occurs at 350 °C but at 200 °C there is no breakdown of the complex as per XRD. According to Raman and XPS analysis, as the temperature rises, the bonds between the metals become weaker, which is visibly seen in Raman and XPS due to the minor peaks of copper sulfide. Scanning electron microscopic analysis confirmed nanometric particles which increase in size with temperature. The photocatalytic evaluation showed that CZTS synthesized at 200 °C performed efficiently in the removal of the two colorants, methylene blue and Rhodamine 6G, achieving 92.80% and 90.65%, respectively. The photocatalytic degradation efficiencies decreased at higher temperatures due to bigger sized CZTS particles as confirmed by SEM results. Computational simulations confirm that CZTS has a highly negative energy -25,764 Ry, confirming its structural stability and higher covalent than ionic character.

5.
Acta Odontol Scand ; 83: 392-403, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38895776

RESUMEN

OBJECTIVES: To evaluate the current evidence of digital workflow feasibility based on the data acquisition methods and the software tools used to fabricate intraoral prostheses for patients with partial or total maxillary and mandibular defects. MATERIALS AND METHODS: An electronic search was performed in PubMed, SCOPUS, and Web of Science using a combination of relevant keywords: digital workflow, digital designing, computer-assisted design-computer aided manufacturing, 3D printing, maxillectomy, and mandibulectomy. The Joanna Briggs Institute Critical Appraisal Tool was used to assess the quality of evidence in the studies reviewed. RESULTS: From a total of 542 references, 33 articles were selected, including 25 on maxillary prostheses and 8 on mandibular prostheses. The use of digital workflows was limited to one or two steps of the fabrication of the prostheses, and only four studies described a complete digital workflow. The most preferred method for data acquisition was intraoral scanning with or without a cone beam computed tomography combination. CONCLUSION: Currently, the fabrication process of maxillofacial prostheses requires combining digital and conventional methods. Simplifying the data acquisition methods and providing user-friendly and affordable software may encourage clinicians to use the digital workflow more frequently for patients requiring maxillofacial prostheses.


Asunto(s)
Prótesis Maxilofacial , Flujo de Trabajo , Humanos , Diseño Asistido por Computadora , Estudios de Factibilidad , Impresión Tridimensional , Programas Informáticos , Diseño de Prótesis
6.
Eur J Nutr ; 62(5): 2269-2278, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37083722

RESUMEN

PURPOSE: Resistant starch (RS) content has exhibited beneficial effects on glycemic control; however, few studies have investigated the effects of this substance on postprandial responses and appetite in subjects with type 2 diabetes (T2D). Here, we aimed to examine the effects of RS from two sources on glycemic response (GR), postprandial lipemia, and appetite in subjects with T2D. METHODS: In a randomized and crossover study, 17 subjects with T2D consumed native banana starch (NBS), high-amylose maize starch (HMS) or digestible maize starch (DMS) for 4 days. On day 5, a 6-h oral meal tolerance test (MTT) was performed to evaluate glycemic and insulinemic responses as well as postprandial lipemia. Besides, subjective appetite assessment was measured using a visual analogue scale. RESULTS: NBS induced a reduction on fasting glycemia, glycemia peak and insulinemic response during MTT. However, no modifications on postprandial lipemia were observed after RS treatments. Both NBS and HMS reduced hunger and increased satiety. CONCLUSION: NBS supplementation induced more beneficial effects on glycemic metabolism than HMS even when all interventions were matched for digestible starch content. RS intake did not modify postprandial lipemia, however, positively affected subjective appetite rates. TRIAL REGISTRATION: This trial was retrospectively registered at www.anzctr.org.au (ACTRN12621001382864) on October 11, 2021.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hiperlipidemias , Humanos , Apetito , Almidón Resistente/farmacología , Estudios Cruzados , Glucemia/metabolismo , Insulina , Almidón/metabolismo , Periodo Posprandial
7.
Environ Res ; 235: 116597, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37442255

RESUMEN

Digestate is a rich source of nutrients that can be applied in agricultural fields as fertilizer or irrigation water. However, most of the research about application of digestate have focused on its agronomic properties and neglected the potential harm of the presence of contaminants of emerging concern (CECs). Aadvanced oxidation processes (AOPs) have proved to be effective for removing these compounds from drinking water, yet there are some constrains to treat wastewater and digestate mainly due to their complex matrix. In this study, the feasibility to remove different CECs from digestate using O3 and O3/H2O2 was assessed, and the general effect of the matrix in the oxidation was explained. While the lab-scale ozonation provided an ozone dose of 1.49 mg O3/mg DOC in 5 h treatment, almost all the compounds were removed at a lower ozone dose of maximum 0.48 mg O3/mg DOC; only ibuprofen required a higher dose of 1.1 mg O3/mg DOC to be oxidized. The digestate matrix slowed down the kinetic ozonation rate to approximately 1% compared to the removal rate in demineralized water. The combined treatment (O3/H2O2) showed the additional contribution of H2O2 by decreasing the ozone demand by 59-75% for all the compounds. The acute toxicity of the digestate, measured by the inhibition of Vibrio fisheries luminescence, decreased by 18.1% during 5 h ozonation, and by 34% during 5 h O3/H2O2 treatment. Despite the high ozone consumption, the ozone dose (mg O3/mg DOC) required to remove all CECs from digestate supernatant was in the range or lower than what has been reported for other (waste-)water matrix, implying that ozonation can be considered as a post-AD treatment to produce cleaner stream for agricultural purposes.


Asunto(s)
Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Aguas del Alcantarillado , Peróxido de Hidrógeno , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Aguas Residuales , Agua , Oxidación-Reducción
8.
Environ Res ; 237(Pt 1): 116914, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37597824

RESUMEN

To investigate the influence of high-pressure and shear effects introduced by a concentrated oxygen supply system on the membrane filtration performance, a laboratory-scale membrane bioreactor (MBR) fed artificial municipal wastewater was operated continuously for 80 days in four phases equipped with different aerations systems: (P1) bubble diffusers (days 0-40), (P2) concentrated oxygen supply system, the supersaturated dissolved oxygen (SDOX) (days 41-56), (P3) bubble diffusers (days 57-74), and (P4) SDOX (days 75-80). Various sludge physical-chemical parameters, visual inspection of the membrane, and permeability evaluations were performed. Results showed that the high-pressure effects contributed to fouling of the membranes compared to the bubble diffuser aeration system. Biofouling by microorganisms appeared to be the main contributor to the cake layer when bubble diffusers were used, while fouling by organic matter seemed to be the main contributor to the cake layer when SDOX was used. Small particle size distribution (PSD) (ranging from 1 to 10 and 1-50 µm in size) fractions are a main parameter affecting the intense fouling of membranes (e.g., formation of a dense and thin cake layer). However, PSD alone cannot explain the worsened membrane fouling tendency. Therefore, it can be assumed that a combination of several factors (which certainly includes PSD) led to the severe membrane fouling caused by the high-pressure and shear.

9.
Curr Urol Rep ; 24(3): 121-126, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36401111

RESUMEN

PURPOSE OF THE REVIEW: Genital mutilation in males can range from minor injuries (cuts from a blade) to severe urological emergencies (testicular or penile amputation). Due to the rarity of these events, there is a lack of extensive reports, as most of the available literature is regarding single cases. Genital mutilation has been associated with psychotic and non-psychotic causes, psychiatric conditions, drug consumption, sexual practices, or even cultural or religious beliefs. It is crucial to perform a psychiatric evaluation of these patients to obtain the best therapeutic approach. This manuscript serves as a review of the currently available knowledge regarding male genital mutilation. RECENT FINDINGS: A great variety of reasons have been associated with genital mutilation. Previous authors have distinguished between those that present with a clear mental health precursor from cases with no psychotic background. Nevertheless, sometimes, it is difficult to make this distinction. Recently, reconstructive techniques for amputation cases have moved towards a microsurgical approach in order to improve outcomes. A holistic therapeutic approach must be performed to increase the chances of effective treatment. Close collaboration between urologists, psychiatrists, and emergency doctors is essential to ensure the best care for patients performing genital mutilation. Future publications must evaluate differences in treatment options and the impact that these have on the long-term well-being of patients undergoing genital self-mutilation.


Asunto(s)
Pene , Automutilación , Humanos , Masculino , Pene/cirugía , Pene/lesiones , Automutilación/psicología , Testículo
10.
J Dairy Sci ; 106(8): 5468-5473, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37296052

RESUMEN

The objective of the study was to identify the presence of toxigenic fungi Aspergillus spp. and Fusarium spp. in domestic flies collected from dairy farms. We selected 10 dairy farms distributed in the central valley of the state of Aguascalientes, México. The flies were trapped using entomological traps with an olfactory attractant in 7 sites of the farm (silo-cutting surface, feed store, milking parlor, 3 feeders, and the rearing room). The fungi were cultivated in Sabouraud agar through direct sowing by serial dilutions to obtain the isolates, and a taxonomical identification was carried out under the microscope. The aflatoxins and zearalenone production capacity of the pure isolates were quantified using the ELISA test. The flies were present in all of the capture sites (45.3 flies, 567 mg, trap per day). We obtained 50 isolates of Aspergillus spp. genus, 12 of which produced aflatoxins (327 ± 143 µg/kg), whereas from 56 of the Fusarium spp. isolates, 10 produced large quantities of zearalenone (3,132 ± 665 µg/kg). These results suggest that the presence of domestic flies on dairy farms can constitute a source of dissemination for toxigenic fungi that can eventually contaminate grains and forage that are part of the daily cattle diet.


Asunto(s)
Aflatoxinas , Fusarium , Moscas Domésticas , Muscidae , Zearalenona , Animales , Bovinos , Moscas Domésticas/microbiología , Granjas , Aspergillus , Hongos
11.
Acta Odontol Scand ; 81(5): 349-357, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36539386

RESUMEN

Objetive. During the last few years, cyanoacrylate has been used for wound closure in oral and maxillofacial surgery with growing frequency. When comparing cyanoacrylate with sutures, some authors report similar experiences, while others have found differences. Some agree on the similar outcomes obtained between cyanoacrylate and sutures, others have registered better effects with cyanoacrylate, and others with sutures. Therefore, the aim of this systematic review (SR) was to evaluate postoperative parameters - pain, swelling, trismus, healing and complications (bleeding and infection) - after lower third molar (LTM) removal using cyanoacrylate compared with sutures. Materials and methods. Electronic and manual literature searches were conducted independently by two reviewers up to March 2022. Results. Four studies met the pre-established inclusion criteria and were included for descriptive analysis. These were controlled clinical trials comparing the effects of cyanoacrylate with sutures in 116 patients and 232 split-mouth cases. Pain and haemostasis were significantly reduced on the cyanoacrylate group, swelling showed the same results on two of the studies analysed, trismus and healing had no significant differences between both groups. Conclusions. Both techniques were found to be effective in terms of wound closure, proposing cyanoacrylate as an effective resource that should be investigated in future research. Nevertheless, the literature on cyanoacrylate is scarce and lacks comparative studies of its outcomes and effects.


Asunto(s)
Cianoacrilatos , Diente Impactado , Humanos , Cianoacrilatos/uso terapéutico , Trismo/etiología , Trismo/tratamiento farmacológico , Tercer Molar/cirugía , Boca , Suturas , Dolor Postoperatorio/tratamiento farmacológico
12.
Exp Appl Acarol ; 91(2): 331-338, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37751012

RESUMEN

Rhipicephalus sanguineus s.l. is an intra- and peridomiciliary tick of medical and veterinary importance, whose control is carried out through the application of various ixodicides, to which it can develop resistance. The objective of this work was to determine the discriminant doses (d.d.) to identify resistance against three ixodicides - fipronil, flumethrin and coumaphos - in R. sanguineus s.l. larvae originating from Mexico. Engorged ticks were collected from naturally infested dogs residing in rural communities in five Mexican states; the dogs had no history of recent treatment with ixodicides. All ticks were identified as R. sanguineus s.l. They were incubated for 25 days and their progeny was used in the larval package test (LPT) to be exposed to d.d. as determined in Rhipicephalus microplus, and those that were susceptible were analyzed using the LPT with six concentrations, for fipronil from 0.1 to 0.003125%, for flumethrin from 0.02 to 0.000625% and for coumaphos from 0.4 to 0.0125%. Mortality was analyzed with Probit methodology, to calculate the 50 and 99% lethal concentrations (LC50 and LC99). The d.d. was determined as a consensus value by multiplying the LC99 value × 2. Nine double susceptible samples (fipronil + flumethrin) and one triple susceptible sample (fipronil + flumethrin + coumaphos) were found; the d.d. determined were fipronil 0.05%, flumethrin 0.01% and coumaphos 0.43%. These doses can be used to rapidly and inexpensively identify resistant populations in samples collected in the field.

13.
Mol Phylogenet Evol ; 173: 107516, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35577290

RESUMEN

Genomic data are a powerful tool for the elucidation of evolutionary patterns at the population level and above. The combined analysis of genomic and morphological data can result in species delimitation hypotheses that reflect evolutionary history better than traditional taxonomy or any individual source of evidence. Here, we used thousands of single nucleotide polymorphisms, mitochondrial sequences, and comprehensive morphological data to characterize the evolutionary history of the ridge-tailed monitors in the Varanus acanthurus complex (V. acanthurus, V. baritji, and V. storri), a group of saxicolous lizards with a wide distribution in Australia, the driest vegetated continent. We found substantial genetic structure in the group and identify nine geographically clustered populations. Based on admixture patterns and species delimitation analyses we propose a taxonomic scheme that differs from current taxonomy. We consider V. acanthurus as monotypic, synonymize V. baritji with V. a. insulanicus (as a redefined V. insulanicus), elevate the subspecies of V. storri to full species (V. storri and V. ocreatus), and describe a new species from a previously identified center of endemism. The relationships among the species remain unresolved, likely as a result of fast speciation. Our study highlights the capability of large datasets to illuminate admixture patterns, biogeographic history, and species limits, even when phylogeny is not completely resolved. Furthermore, our results highlight the impact that the Cenozoic aridification of Australia had on saxicolous taxa and the role of mesic rocky escarpments as refugia. These habitats apparently allowed the persistence of lineages that became sources of colonization for arid environments.


Asunto(s)
Lagartos , Animales , Evolución Biológica , Ecosistema , Genoma , Filogenia
14.
Syst Biol ; 70(5): 877-890, 2021 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-33512509

RESUMEN

Hybridization between species occurs more frequently in vertebrates than traditionally thought, but distinguishing ancient hybridization from other phenomena that generate similar evolutionary patterns remains challenging. Here, we used a comprehensive workflow to discover evidence of ancient hybridization between the Komodo dragon (Varanus komodoensis) from Indonesia and a common ancestor of an Australian group of monitor lizards known colloquially as sand monitors. Our data comprise $>$300 nuclear loci, mitochondrial genomes, phenotypic data, fossil and contemporary records, and past/present climatic data. We show that the four sand monitor species share more nuclear alleles with $V$. komodoensis than expected given a bifurcating phylogeny, likely as a result of hybridization between the latter species and a common ancestor of sand monitors. Sand monitors display phenotypes that are intermediate between their closest relatives and $V$. komodoensis. Biogeographic analyses suggest that $V$. komodoensis and ancestral sand monitors co-occurred in northern Australia. In agreement with the fossil record, this provides further evidence that the Komodo dragon once inhabited the Australian continent. Our study shows how different sources of evidence can be used to thoroughly characterize evolutionary histories that deviate from a treelike pattern, that hybridization can have long-lasting effects on phenotypes, and that detecting hybridization can improve our understanding of evolutionary and biogeographic patterns.[Biogeography; introgression; Komodo dragon; phylogenetic networks; phylogenomics; reticulation; Varanus.].


Asunto(s)
Lagartos , Animales , Australia , Fósiles , Hibridación Genética , Lagartos/genética , Filogenia
15.
Sensors (Basel) ; 22(19)2022 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-36236716

RESUMEN

This research presents the technical considerations for implementing the CeCi (Computer Electronic Communication Interface) social robot. In this case, this robot responds to the need to achieve technological development in an emerging country with the aim of social impact and social interaction. There are two problems with the social robots currently on the market, which are the main focus of this research. First, their costs are not affordable for companies, universities, or individuals in emerging countries. The second is that their design is exclusively oriented to the functional part with a vision inherent to the engineers who create them without considering the vision, preferences, or requirements of the end users, especially for their social interaction. This last reason ends causing an aversion to the use of this type of robot. In response to the issues raised, a low-cost prototype is proposed, starting from a commercial platform for research development and using open source code. The robot design presented here is centered on the criteria and preferences of the end user, prioritizing acceptability for social interaction. This article details the selection process and hardware capabilities of the robot. Moreover, a programming section is provided to introduce the different software packages used and adapted for the social interaction, the main functions implemented, as well as the new and original part of the proposal. Finally, a list of applications currently developed with the robot and possible applications for future research are discussed.


Asunto(s)
Robótica , Ingeniería , Humanos , Interacción Social , Programas Informáticos , Interfaz Usuario-Computador
16.
Acta Vet Hung ; 70(4): 269-273, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36240048

RESUMEN

The objectives of the study were to estimate the prevalence of anti-Toxoplasma gondii antibodies in free-range chickens in Aguascalientes, Mexico, its association with certain risk factors, and the frequency of parasite DNA in the heart. Eighty-one small rural family farms were included, and blood and heart samples were taken from 150 clinically healthy, adult, free-range chickens. Serum samples were processed by indirect immunofluorescence antibody test considering a dilution of 1:16 as a positive reaction, while the DNA detection was done by PCR. The correlation between the presence of antibodies and the potential risk factors was estimated with logistic regression. The overall seroprevalence in the examined populations was 67%, with a range from 33% to 100% among municipalities, and 78% of the farms having at least one seropositive bird. The PCR test identified the presence of parasite DNA for one case only. Among the variables, the presence of cats and the presence of other animal species on the farm were the ones that had the highest values, while the presence of feral cats and the presence of noxious fauna were also identified as potential risk factors. The results indicate high soil contamination by T. gondii oocysts, which implies the active role of cats living on the farms.


Asunto(s)
Enfermedades de los Gatos , Parásitos , Toxoplasmosis Animal , Animales , Gatos , Pollos , Estudios Seroepidemiológicos , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/parasitología , México/epidemiología , ADN
17.
Commun Nonlinear Sci Numer Simul ; 115: 106731, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35910551

RESUMEN

In this article we mainly extend a newly introduced deterministic model for the COVID-19 disease to a stochastic setting. More precisely, we incorporated randomness in some coefficients by assuming that they follow a prescribed stochastic dynamics. In this way, the model variables are now represented by stochastic process, that can be simulated by appropriately solving the system of stochastic differential equations. Thus, the model becomes more complete and flexible than the deterministic analogous, as it incorporates additional uncertainties which are present in more realistic situations. In particular, confidence intervals for the main variables and worst case scenarios can be computed.

18.
Plant Foods Hum Nutr ; 77(2): 265-270, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35618894

RESUMEN

α-tocopherol is found in high concentrations in avocado fruit mesocarp, however, its accumulation and genetic control during maturation and ripening has not been elucidated. Based in the relevance of VTE1 and VTE5 genes in tocopherol biosynthesis and aiming to determine the association between tocopherol accumulation and expression of tocopherol biosynthetic genes, gene expression of VTE1 and VTE5 were evaluated through the time during three developmental stages: before harvest at 100, 160 and 220 days after flowering (DAF) and after harvest (220 DAF + 5) in two contrasting avocado genotypes (San Miguel and AVO40). San Miguel reached the highest levels at 220 DAF, whereas AVO40 increased α-tocopherol only after ripening (220 DAF + 5). A genome-wide search for VTE1 and VTE5 allowed to identify one and three genes, respectively. Both genotypes showed contrasting patterns of gene expression. Interestingly, AVO40 showed a highly positive correlation between α-tocopherol levels and gene expression of VTE1 and all VTE5 variants. On the other hand, San Miguel showed only a positive correlation between α-tocopherol level and VTE1gene expression.


Asunto(s)
Persea , Tocoferoles , Frutas/genética , Regulación de la Expresión Génica de las Plantas , Genotipo , Persea/genética , Vitamina E/metabolismo , alfa-Tocoferol/metabolismo
19.
J Gen Virol ; 102(11)2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34723786

RESUMEN

Hepatitis B virus (HBV) infection is a global public health problem with about 257 million chronically infected people and over 887000 deaths annually. In this study, 32 whole HBV genomes of various genotypes were amplified from clinical isolates to create transfection clones. The clones were sequenced, and their biological properties characterized by transfecting linear HBV clones into HepG2 cells. We analysed the SPI and SPII promotor regions, X-gene, BCP/PC sequences, core, preS/S and HBV polymerase sequences. HBV clones analysed in this study revealed differential replication kinetics of viral nucleic acids and expression of proteins. Sequence analysis of HBV clones revealed mutations in preS1, preS2 and S genes; deletion and insertion and point mutations in BCP/PC region; including novel and previously reported mutations. Among the patient samples tested, HBV genotype B clones were more likely to have higher frequencies of mutations, while sub-genotype A1 and A2 clones tended to have fewer mutations. No polymerase drug resistant mutations were seen. HBeAg mutations were primarily in the BCP/PC region in genotype B, but core truncations were found in genotype E. S gene mutations affecting HBsAg expression and detection were seen in all genotypes except A2. Using an HBV clone with repetitive terminal sequences and a SapI restriction site allowed us to analyse HBV analyte production in cell culture and characterize the genetics of viral phenotypes using complete HBV genomes isolated from serum/plasma samples of infected patients.


Asunto(s)
Genoma Viral , Virus de la Hepatitis B/genética , Hepatitis B/virología , ADN Viral/genética , Variación Genética , Genotipo , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Mutación , Filogenia , Transfección
20.
Mol Phylogenet Evol ; 161: 107181, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33892100

RESUMEN

Advances from empirical studies in phylogeography, systematics and species delimitation highlight the importance of integrative approaches for quantifying taxonomic diversity. Genomic data have greatly improved our ability to discern both systematic diversity and evolutionary history. Here we combine analyses of mitochondrial DNA sequences, thousands of genome-wide SNPs and linear and geometric morphometrics on Antaresia, a clade of four currently recognised dwarf pythons from Australia and New Guinea (Antaresia childreni, A. stimsoni, A. maculosa and A. perthensis). Our integrative analyses of phylogenetics, population structure, species delimitation, historical demography and morphometrics revealed that the true evolutionary diversity is not well reflected in the current appraisal of the diversity of the group. We find that Antaresia childreni and A. stimsoni comprise a widespread network of populations connected by gene flow and without evidence of species-level divergence among them. However, A. maculosa shows considerable genetic structuring which leads us to recognise two subspecies in northeastern Australia and a new species in Torres Strait and New Guinea. These two contrasting cases of over and under estimation of diversity, respectively, illustrate the power of thorough integrative approaches into understanding evolution of biodiversity. Furthermore, our analyses of historical demographic patterns highlight the importance of the Kimberley, Pilbara and Cape York as origins of biodiversity in Australia.


Asunto(s)
Boidae/clasificación , Boidae/genética , Filogenia , Filogeografía , Animales , Tamaño Corporal , Boidae/anatomía & histología , ADN Mitocondrial/genética , Flujo Génico/genética
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