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1.
Proc Natl Acad Sci U S A ; 120(32): e2217800120, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37498871

RESUMO

Small molecules directly targeting the voltage-gated sodium channel (VGSC) NaV1.7 have not been clinically successful. We reported that preventing the addition of a small ubiquitin-like modifier onto the NaV1.7-interacting cytosolic collapsin response mediator protein 2 (CRMP2) blocked NaV1.7 function and was antinociceptive in rodent models of neuropathic pain. Here, we discovered a CRMP2 regulatory sequence (CRS) unique to NaV1.7 that is essential for this regulatory coupling. CRMP2 preferentially bound to the NaV1.7 CRS over other NaV isoforms. Substitution of the NaV1.7 CRS with the homologous domains from the other eight VGSC isoforms decreased NaV1.7 currents. A cell-penetrant decoy peptide corresponding to the NaV1.7-CRS reduced NaV1.7 currents and trafficking, decreased presynaptic NaV1.7 expression, reduced spinal CGRP release, and reversed nerve injury-induced mechanical allodynia. Importantly, the NaV1.7-CRS peptide did not produce motor impairment, nor did it alter physiological pain sensation, which is essential for survival. As a proof-of-concept for a NaV1.7 -targeted gene therapy, we packaged a plasmid encoding the NaV1.7-CRS in an AAV virus. Treatment with this virus reduced NaV1.7 function in both rodent and rhesus macaque sensory neurons. This gene therapy reversed and prevented mechanical allodynia in a model of nerve injury and reversed mechanical and cold allodynia in a model of chemotherapy-induced peripheral neuropathy. These findings support the conclusion that the CRS domain is a targetable region for the treatment of chronic neuropathic pain.


Assuntos
Dor Crônica , Neuralgia , Animais , Hiperalgesia/induzido quimicamente , Dor Crônica/genética , Dor Crônica/terapia , Macaca mulatta/metabolismo , Neuralgia/genética , Neuralgia/terapia , Canal de Sódio Disparado por Voltagem NAV1.7/genética , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Gânglios Espinais/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.8
2.
PLoS Genet ; 18(8): e1010337, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36007015

RESUMO

Central and eastern chimpanzees are infected with Simian Immunodeficiency Virus (SIV) in the wild, typically without developing acute immunodeficiency. Yet the recent zoonotic transmission of chimpanzee SIV to humans, which were naïve to the virus, gave rise to the Human Immunodeficiency Virus (HIV), which causes AIDS and is responsible for one of the deadliest pandemics in human history. Chimpanzees have likely been infected with SIV for tens of thousands of years and have likely evolved to reduce its pathogenicity, becoming semi-natural hosts that largely tolerate the virus. In support of this view, central and eastern chimpanzees show evidence of positive selection in genes involved in SIV/HIV cell entry and immune response to SIV, respectively. We hypothesise that the population first infected by SIV would have experienced the strongest selective pressure to control the lethal potential of zoonotic SIV, and that population genetics will reveal those first critical adaptations. With that aim we used population genetics to investigate signatures of positive selection in the common ancestor of central-eastern chimpanzees. The genes with signatures of positive selection in the ancestral population are significantly enriched in SIV-related genes, especially those involved in the immune response to SIV and those encoding for host genes that physically interact with SIV/HIV (VIPs). This supports a scenario where SIV first infected the central-eastern ancestor and where this population was under strong pressure to adapt to zoonotic SIV. Interestingly, integrating these genes with candidates of positive selection in the two infected subspecies reveals novel patterns of adaptation to SIV. Specifically, we observe evidence of positive selection in numerous steps of the biological pathway responsible for T-helper cell differentiation, including CD4 and multiple genes that SIV/HIV use to infect and control host cells. This pathway is active only in CD4+ cells which SIV/HIV infects, and it plays a crucial role in shaping the immune response so it can efficiently control the virus. Our results confirm the importance of SIV as a selective factor, identify specific genetic changes that may have allowed our closest living relatives to reduce SIV's pathogenicity, and demonstrate the potential of population genomics to reveal the evolutionary mechanisms used by naïve hosts to reduce the pathogenicity of zoonotic pathogens.


Assuntos
Infecções por HIV , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , HIV/genética , Humanos , Pan troglodytes/genética , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Vírus da Imunodeficiência Símia/genética
3.
Ann Emerg Med ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38795078

RESUMO

STUDY OBJECTIVE: Acute musculoskeletal pain in emergency department (ED) patients is frequently severe and challenging to treat with medications alone. The purpose of this study was to determine the feasibility, acceptability, and effectiveness of adding ED acupuncture to treat acute episodes of musculoskeletal pain in the neck, back, and extremities. METHODS: In this pragmatic 2-stage adaptive open-label randomized clinical trial, Stage 1 identified whether auricular acupuncture (AA; based on the battlefield acupuncture protocol) or peripheral acupuncture (PA; needles in head, neck, and extremities only), when added to usual care was more feasible, acceptable, and efficacious in the ED. Stage 2 assessed effectiveness of the selected acupuncture intervention(s) on pain reduction compared to usual care only (UC). Licensed acupuncturists delivered AA and PA. They saw and evaluated but did not deliver acupuncture to the UC group as an attention control. All participants received UC from blinded ED providers. Primary outcome was 1-hour change in 11-point pain numeric rating scale. RESULTS: Stage 1 interim analysis found both acupuncture styles similar, so Stage 2 continued all 3 treatment arms. Among 236 participants randomized, demographics and baseline pain were comparable across groups. When compared to UC alone, reduction in pain was 1.6 (95% confidence interval [CI]: 0.7 to 2.6) points greater for AA+UC and 1.2 (95% CI: 0.3 to 2.1) points greater for PA+UC patients. Participants in both treatment arms reported high satisfaction with acupuncture. CONCLUSION: ED acupuncture is feasible and acceptable and can reduce acute musculoskeletal pain better than UC alone.

4.
J Dairy Sci ; 107(6): 3651-3668, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38216038

RESUMO

Dairy farms in the United States have changed in many ways over the past 50 yr. Milk production efficiency has increased greatly, with ∼30% fewer cows producing about twice the amount of milk today. Other improvements include increases in crop yields, fuel efficiency of farm equipment, and efficiency in producing most resources used on farms (e.g. electricity, fuel, fertilizer). These improvements have led to changes in the environmental impact of farms. Through simulation of representative dairy farms in 1971 and 2020, changes in nutrient losses and farmgate life cycle assessments of greenhouse gas (GHG) emissions, fossil energy use, and blue (ground and surface) water use were determined for 6 regions and the United States. For all environmental metrics studied, intensities expressed per unit of fat- and protein-corrected milk produced were reduced, but the total effects over all farms or milk produced increased for 5 of the 13 environmental metrics. Reductions in the impacts of dairy farms in the eastern United States were offset by large increases in western regions because of a major increase in cow numbers in the West. The national average intensity of GHG emissions decreased by 42%, which gave just a 14% increase in the total GHG emissions of all dairy farms over the 50-yr period. The intensity of fossil energy use decreased by 54%, with the total for all farms decreasing by 9%. Water use related to milk production decreased in intensity by 28%, but due to the large increase in dairy production in the dry western regions that have a greater dependence on irrigated feed crops, total blue water use increased by 42%. Major pathways of nitrogen loss included ammonia volatilization, leaching, and denitrification, where total ammonia emissions related to US dairy farms increased by 29%, while leaching losses decreased by 39%, with little change in nitrous oxide emissions. Simulated nitrogen and phosphorus runoff losses totaled for all dairy farms decreased by 27% to 51% through more efficient fertilizer use, reduced tillage, and greater use of cover crops. Emissions of methane and reactive non-methane volatile organic compounds increased by 32% and 53%, respectively, due to greater use of long-term manure storage and silage stored in bunkers and piles. Although much progress has been made in improving production efficiency, continued improvements with new strategies and technologies are needed to meet the demand for dairy products and mitigate total environmental impacts, particularly in view of projected climate variability.


Assuntos
Indústria de Laticínios , Meio Ambiente , Fazendas , Leite , Animais , Estados Unidos , Bovinos , Leite/química , Fertilizantes , Feminino , Gases de Efeito Estufa/análise
5.
Ann Bot ; 131(1): 215-228, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35639931

RESUMO

BACKGROUND AND AIMS: Tandemly repeated DNA and transposable elements represent most of the DNA in higher plant genomes. High-throughput sequencing allows a survey of the DNA in a genome, but whole-genome assembly can miss a substantial fraction of highly repeated sequence motifs. Chrysanthemum nankingense (2n = 2x = 18; genome size = 3.07 Gb; Asteraceae), a diploid reference for the many auto- and allopolyploids in the genus, was considered as an ancestral species and serves as an ornamental plant and high-value food. We aimed to characterize the major repetitive DNA motifs, understand their structure and identify key features that are shaped by genome and sequence evolution. METHODS: Graph-based clustering with RepeatExplorer was used to identify and classify repetitive motifs in 2.14 millions of 250-bp paired-end Illumina reads from total genomic DNA of C. nankingense. Independently, the frequency of all canonical motifs k-bases long was counted in the raw read data and abundant k-mers (16, 21, 32, 64 and 128) were extracted and assembled to generate longer contigs for repetitive motif identification. For comparison, long terminal repeat retrotransposons were checked in the published C. nankingense reference genome. Fluorescent in situ hybridization was performed to show the chromosomal distribution of the main types of repetitive motifs. KEY RESULTS: Apart from rDNA (0.86 % of the total genome), a few microsatellites (0.16 %), and telomeric sequences, no highly abundant tandem repeats were identified. There were many transposable elements: 40 % of the genome had sequences with recognizable domains related to transposable elements. Long terminal repeat retrotransposons showed widespread distribution over chromosomes, although different sequence families had characteristic features such as abundance at or exclusion from centromeric or subtelomeric regions. Another group of very abundant repetitive motifs, including those most identified as low-complexity sequences (9.07 %) in the genome, showed no similarity to known sequence motifs or tandemly repeated elements. CONCLUSIONS: The Chrysanthemum genome has an unusual structure with a very low proportion of tandemly repeated sequences (~1.02 %) in the genome, and a high proportion of low-complexity sequences, most likely degenerated remains of transposable elements. Identifying the presence, nature and genomic organization of major genome fractions enables inference of the evolutionary history of sequences, including degeneration and loss, critical to understanding biodiversity and diversification processes in the genomes of diploid and polyploid Chrysanthemum, Asteraceae and plants more widely.


Assuntos
Chrysanthemum , Retroelementos , Hibridização in Situ Fluorescente , Chrysanthemum/genética , Elementos de DNA Transponíveis , Sequências Repetitivas de Ácido Nucleico , Genômica , Genoma de Planta , Plantas/genética , Evolução Molecular
6.
Ann Bot ; 131(1): 1-10, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36282971

RESUMO

BACKGROUND: Most, if not all, green plant (Virdiplantae) species including angiosperms and ferns are polyploids themselves or have ancient polyploid or whole genome duplication signatures in their genomes. Polyploids are not only restricted to our major crop species such as wheat, maize, potato and the brassicas, but also occur frequently in wild species and natural habitats. Polyploidy has thus been viewed as a major driver in evolution, and its influence on genome and chromosome evolution has been at the centre of many investigations. Mechanistic models of the newly structured genomes are being developed that incorporate aspects of sequence evolution or turnover (low-copy genes and regulatory sequences, as well as repetitive DNAs), modification of gene functions, the re-establishment of control of genes with multiple copies, and often meiotic chromosome pairing, recombination and restoration of fertility. SCOPE: World-wide interest in how green plants have evolved under different conditions - whether in small, isolated populations, or globally - suggests that gaining further insight into the contribution of polyploidy to plant speciation and adaptation to environmental changes is greatly needed. Forward-looking research and modelling, based on cytogenetics, expression studies, and genomics or genome sequencing analyses, discussed in this Special Issue of the Annals of Botany, consider how new polyploids behave and the pathways available for genome evolution. They address fundamental questions about the advantages and disadvantages of polyploidy, the consequences for evolution and speciation, and applied questions regarding the spread of polyploids in the environment and challenges in breeding and exploitation of wild relatives through introgression or resynthesis of polyploids. CONCLUSION: Chromosome number, genome size, repetitive DNA sequences, genes and regulatory sequences and their expression evolve following polyploidy - generating diversity and possible novel traits and enabling species diversification. There is the potential for ever more polyploids in natural, managed and disturbed environments under changing climates and new stresses.


Assuntos
Evolução Molecular , Genoma de Planta , Cromossomos , Plantas/genética , Poliploidia
7.
Ann Bot ; 131(1): 87-108, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-34874999

RESUMO

BACKGROUND AND AIMS: Diploid and polyploid Urochloa (including Brachiaria, Panicum and Megathyrsus species) C4 tropical forage grasses originating from Africa are important for food security and the environment, often being planted in marginal lands worldwide. We aimed to characterize the nature of their genomes, the repetitive DNA and the genome composition of polyploids, leading to a model of the evolutionary pathways within the group including many apomictic species. METHODS: Some 362 forage grass accessions from international germplasm collections were studied, and ploidy was determined using an optimized flow cytometry method. Whole-genome survey sequencing and molecular cytogenetic analysis were used to identify chromosomes and genomes in Urochloa accessions belonging to the 'brizantha' and 'humidicola' agamic complexes and U. maxima. KEY RESULTS: Genome structures are complex and variable, with multiple ploidies and genome compositions within the species, and no clear geographical patterns. Sequence analysis of nine diploid and polyploid accessions enabled identification of abundant genome-specific repetitive DNA motifs. In situ hybridization with a combination of repetitive DNA and genomic DNA probes identified evolutionary divergence and allowed us to discriminate the different genomes present in polyploids. CONCLUSIONS: We suggest a new coherent nomenclature for the genomes present. We develop a model of evolution at the whole-genome level in diploid and polyploid accessions showing processes of grass evolution. We support the retention of narrow species concepts for Urochloa brizantha, U. decumbens and U. ruziziensis, and do not consider diploids and polyploids of single species as cytotypes. The results and model will be valuable in making rational choices of parents for new hybrids, assist in use of the germplasm for breeding and selection of Urochloa with improved sustainability and agronomic potential, and assist in measuring and conserving biodiversity in grasslands.


Assuntos
Brachiaria , Poaceae , Poaceae/genética , Brachiaria/genética , Poliploidia , Ploidias , Genômica
8.
Wound Repair Regen ; 31(3): 393-400, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36905199

RESUMO

Venous leg ulcers, the most common leg ulcer, occur in patients with chronic venous insufficiency due to venous hypertension. Evidence supports the conservative treatment with lower extremity compression, ideally between 30-40 mm Hg. Pressures in this range provide enough force to partially collapse lower extremity veins without restricting arterial flow in patients without peripheral arterial disease. There are many options for applying such compression, and those who apply these devices have varying levels of training and backgrounds. In this quality improvement project, a single observer utilised a reusable pressure monitor to compare pressures applied using different devices by individuals in wound clinics with diverse training from specialties of dermatology, podiatry, and general surgery. Average compression was higher in the dermatology wound clinic (n = 153) compared to the general surgery clinic (n = 53) (35.7 ± 13.3 and 27.2 ± 8.0 mm Hg, respectively, p < 0.0001), and wraps applied by clinic staff (n = 194) were nearly twice as likely as a self-applied wrap (n = 71) to have pressures greater than 40 mm Hg (relative risk: 2.2, 95% confidence interval: 1.136-4.423, p = 0.02). Pressures were also dependent upon the specific compression device used, with CircAid®s (35.5 mm Hg, SD: 12.0 mm Hg, n = 159) providing higher average pressures than Sigvaris Compreflex (29.5 mm Hg, SD: 7.7 mm Hg, n = 53, p = 0.009) and Sigvaris Coolflex (25.2 mm Hg, SD: 8.0 mm Hg, n = 32, p < 0.0001). These results indicate that the device-provided pressure may be dependent on both the compression device and the background and training of the applicator. We propose that standardisation in the training of compression application and increased use of a point-of-care pressure monitor may improve the consistency of applied compression, thus improving adherence to treatment and outcomes in patients with chronic venous insufficiency.


Assuntos
Úlcera da Perna , Úlcera Varicosa , Insuficiência Venosa , Humanos , Bandagens Compressivas , Cicatrização , Úlcera Varicosa/prevenção & controle , Insuficiência Venosa/prevenção & controle
9.
J Chem Phys ; 158(2): 024202, 2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36641380

RESUMO

Although photothermal imaging was originally designed to detect individual molecules that do not emit or small nanoparticles that do not scatter, the technique is now being applied to image and spectroscopically characterize larger and more sophisticated nanoparticle structures that scatter light strongly. Extending photothermal measurements into this regime, however, requires revisiting fundamental assumptions made in the interpretation of the signal. Herein, we present a theoretical analysis of the wavelength-resolved photothermal image and its extension to the large particle scattering regime, where we find the photothermal signal to inherit a nonlinear dependence upon pump intensity, together with a contraction of the full-width-at-half-maximum of its point spread function. We further analyze theoretically the extent to which photothermal spectra can be interpreted as an absorption spectrum measure, with deviations between the two becoming more prominent with increasing pump intensities. Companion experiments on individual 10, 20, and 100 nm radius gold nanoparticles evidence the predicted nonlinear pump power dependence and image contraction, verifying the theory and demonstrating new aspects of photothermal imaging relevant to a broader class of targets.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Ouro/química
10.
Proc Natl Acad Sci U S A ; 117(16): 8750-8756, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32265279

RESUMO

Soil mixing over long (>102 y) timescales enhances nutrient fluxes that support soil ecology, contributes to dispersion of sediment and contaminated material, and modulates fluxes of carbon through Earth's largest terrestrial carbon reservoir. Despite its foundational importance, we lack robust understanding of the rates and patterns of soil mixing, largely due to a lack of long-timescale data. Here we demonstrate that luminescence, a light-sensitive property of minerals used for geologic dating, can be used as a long-timescale sediment tracer in soils to reveal the structure of soil mixing. We develop a probabilistic model of transport and mixing of tracer particles and associated luminescence in soils and compare with a global compilation of luminescence versus depth in various locations. The model-data comparison reveals that soil mixing rate varies over the soil depth, with this depth dependency persisting across climate and ecological zones. The depth dependency is consistent with a model in which mixing intensity decreases linearly or exponentially with depth, although our data do not resolve between these cases. Our findings support the long-suspected idea that depth-dependent mixing is a spatially and temporally persistent feature of soils. Evidence for a climate control on the patterns and intensities of soil mixing with depth remains elusive and requires the further study of soil mixing processes.

11.
Proc Natl Acad Sci U S A ; 117(29): 17094-17103, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32611817

RESUMO

Declining ejaculate performance with male age is taxonomically widespread and has broad fitness consequences. Ejaculate success requires fully functional germline (sperm) and soma (seminal fluid) components. However, some aging theories predict that resources should be preferentially diverted to the germline at the expense of the soma, suggesting differential impacts of aging on sperm and seminal fluid and trade-offs between them or, more broadly, between reproduction and lifespan. While harmful effects of male age on sperm are well known, we do not know how much seminal fluid deteriorates in comparison. Moreover, given the predicted trade-offs, it remains unclear whether systemic lifespan-extending interventions could ameliorate the declining performance of the ejaculate as a whole. Here, we address these problems using Drosophila melanogaster. We demonstrate that seminal fluid deterioration contributes to male reproductive decline via mating-dependent mechanisms that include posttranslational modifications to seminal proteins and altered seminal proteome composition and transfer. Additionally, we find that sperm production declines chronologically with age, invariant to mating activity such that older multiply mated males become infertile principally via reduced sperm transfer and viability. Our data, therefore, support the idea that both germline and soma components of the ejaculate contribute to male reproductive aging but reveal a mismatch in their aging patterns. Our data do not generally support the idea that the germline is prioritized over soma, at least, within the ejaculate. Moreover, we find that lifespan-extending systemic down-regulation of insulin signaling results in improved late-life ejaculate performance, indicating simultaneous amelioration of both somatic and reproductive aging.


Assuntos
Envelhecimento , Drosophila melanogaster , Proteínas de Plasma Seminal , Espermatozoides , Envelhecimento/genética , Envelhecimento/fisiologia , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Feminino , Fertilidade/genética , Fertilidade/fisiologia , Infertilidade Masculina/genética , Infertilidade Masculina/fisiopatologia , Masculino , Proteoma/análise , Proteoma/genética , Proteoma/fisiologia , Proteínas de Plasma Seminal/análise , Proteínas de Plasma Seminal/fisiologia , Comportamento Sexual Animal/fisiologia , Espermatozoides/química , Espermatozoides/fisiologia
12.
Brain Behav Immun ; 104: 6-15, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35550854

RESUMO

Loneliness is a potent psychosocial stressor that predicts poor health and mortality among older adults, possibly in part by accelerating age-related declines in immunocompetence. Mindfulness interventions have shown promise for reducing loneliness and improving markers of physical health. In a sample of lonely older adults, this two-arm parallel trial tested whether mindfulness training enhances stimulated interleukin-6 (IL-6) production, a measure of innate immune responsivity. Lonely older adults (65-85 years; N = 190) were randomized to an 8-week Mindfulness-Based Stress Reduction (MBSR) or control Health Enhancement Program (HEP) intervention. Lipopolysaccharide (LPS)-stimulated production of IL-6 was measured in vitro by blinded outcome assessors at pre-intervention, post-intervention, and 3-month follow-up. Mixed-effects linear models tested time (pre, post, follow-up) by condition (MBSR vs. HEP) effects. As predicted, a significant time × condition effect on stimulated IL-6 production was observed across pre, post, and follow-up timepoints. Significant MBSR vs. HEP differences emerged from pre- to post-intervention (p =.009, d = 0.38) and from pre-intervention to 3-month follow-up (p =.017, d = 0.35), with larger increases in IL-6 production following MBSR compared to HEP. No study-related adverse events were reported. Results show that mindfulness training may be effective for boosting innate immunocompetence among lonely older adults. Given that immunocompetence tends to decline with age, mindfulness training may help to counteract the effects of aging and psychosocial stress on infection risk and recovery from injury.


Assuntos
Atenção Plena , Expressão Gênica , Interleucina-6 , Solidão , Atenção Plena/métodos , Estresse Psicológico/terapia , Estresse Psicológico/psicologia , Resultado do Tratamento , Humanos , Idoso , Idoso de 80 Anos ou mais
13.
Ann Bot ; 130(5): 657-669, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36112370

RESUMO

BACKGROUND: Urochloa (syn. Brachiaria) is a genus of tropical grasses sown as forage feedstock, particularly in marginal soils. Here we aimed to clarify the genetic diversity and population structure in Urochloa species to understand better how population evolution relates to ploidy level and occurrence of apomictic reproduction. METHODS: We explored the genetic diversity of 111 accessions from the five Urochloa species used to develop commercial cultivars. These accessions were conserved from wild materials collected at their centre of origin in Africa, and they tentatively represent the complete Urochloa gene pool used in breeding programmes. We used RNA-sequencing to generate 1.1 million single nucleotide polymorphism loci. We employed genetic admixture, principal component and phylogenetic analyses to define subpopulations. RESULTS: We observed three highly differentiated subpopulations in U. brizantha, which were unrelated to ploidy: one intermixed with U. decumbens, and two diverged from the former and the other species in the complex. We also observed two subpopulations in U. humidicola, unrelated to ploidy; one subpopulation had fewer accessions but included the only characterized sexual accession in the species. Our results also supported a division of U. decumbens between diploids and polyploids, and no subpopulations within U. ruziziensis and U. maxima. CONCLUSIONS: Polyploid U. decumbens are more closely related to polyploid U. brizantha than to diploid U. decumbens, which supports the divergence of both polyploid groups from a common tetraploid ancestor and provides evidence for the hybridization barrier of ploidy. The three differentiated subpopulations of apomictic polyploid U. brizantha accessions constitute diverged ecotypes, which can probably be utilized in hybrid breeding. Subpopulations were not observed in non-apomictic U. ruziziensis. Sexual Urochloa polyploids were not found (U. brizantha, U. decumbens) or were limited to small subpopulations (U. humidicola). The subpopulation structure observed in the Urochloa sexual-apomictic multiploidy complexes supports geographical parthenogenesis, where the polyploid genotypes exploit the evolutionary advantage of apomixis, i.e. uniparental reproduction and clonality, to occupy extensive geographical areas.


Assuntos
Apomixia , Brachiaria , Brachiaria/genética , Apomixia/genética , Filogenia , Poaceae/genética , Poliploidia
14.
Biol Lett ; 18(3): 20210552, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35259944

RESUMO

Evolutionary arms races can alter both parasite infectivity and host resistance, and it is difficult to separate the effects of these twin determinants of infection outcomes. We used a co-introduced, invasive host-parasite system (the lungworm Rhabdias pseudosphaerocephala and cane toads Rhinella marina), where rapid adaptation and dispersal have led to population differences in infection resistance. We quantified behavioural responses of parasite larvae to skin-chemical cues of toads from different invasive populations, and rates at which juvenile hosts became infected following standardized exposure to lungworms. Chemical cues from toad skin altered host-seeking behaviour by parasites, similarly among populations. The number of infection attempts (parasite larvae entering the host's body) also did not differ between populations, but rates of successful infection (establishment of adult worm in host lungs) were higher for range-edge toads than for range-core conspecifics. Thus, lower resistance to parasite infection in range-edge juvenile toads appears to be due to less effective immune defences of the host rather than differential behavioural responses of the parasite. In this ongoing host-parasite arms race, changing outcomes appear to be driven by shifts in host immunocompetence.


Assuntos
Parasitos , Infecções por Rhabditida , Rhabditoidea , Animais , Evolução Biológica , Bufo marinus , Espécies Introduzidas , Infecções por Rhabditida/epidemiologia , Infecções por Rhabditida/parasitologia , Rhabditoidea/fisiologia
15.
Chromosome Res ; 29(3-4): 301-312, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34331632

RESUMO

The interest in Robertsonian fusion chromosomes (Rb fusions), sometimes referred to as Robertsonian translocations, derives from their impact on mammalian karyotype evolution, as well from their influence on fertility and disease. The formation of a Rb chromosome necessitates the occurrence of double strand breaks in the pericentromeric regions of two chromosomes in the satellite DNA (satDNA) sequences. Here, we report on the fine-scale molecular analysis of the centromeric satDNA families in the Rb(1;29) translocation of domestic cattle and six antelope species of the subfamily Bovinae. We do so from two perspectives: its occurrence as a chromosomal abnormality in cattle and, secondly, as a fixed evolutionarily rearrangement in spiral-horned antelope (Tragelaphini). By analysing the reorganization of satDNAs in the centromeric regions of translocated chromosomes, we show that Rb fusions are multistep, complex rearrangements which entail the precise elimination and reorganization of specific (peri)centromeric satDNA sequences. Importantly, these structural changes do not influence the centromeric activity of the satellite DNAs that provide segregation stability to the translocated chromosome. Our results suggest a common mechanism for Rb fusions in these bovids and, more widely, for mammals in general.


Assuntos
Centrômero , DNA Satélite , Animais , Bovinos/genética , Centrômero/genética , DNA Satélite/genética , Rearranjo Gênico , Ruminantes , Translocação Genética
16.
Chromosome Res ; 29(3-4): 373-390, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34657216

RESUMO

Chromosome identification is essential for linking sequence and chromosomal maps, verifying sequence assemblies, showing structural variations and tracking inheritance or recombination of chromosomes and chromosomal segments during evolution and breeding programs. Unfortunately, identification of individual chromosomes and chromosome arms has been a major challenge for some economically important crop species with a near-continuous chromosome size range and similar morphology. Here, we developed oligonucleotide-based chromosome-specific probes that enabled us to establish a reference chromosome identification system for oil palm (Elaeis guineensis Jacq., 2n = 32). Massive oligonucleotide sequence pools were anchored to individual chromosome arms using dual and triple fluorescent in situ hybridization (EgOligoFISH). Three fluorescently tagged probe libraries were developed to contain, in total 52,506 gene-rich single-copy 47-mer oligonucleotides spanning each 0.2-0.5 Mb across strategically placed chromosome regions. They generated 19 distinct FISH signals and together with rDNA probes enabled identification of all 32 E. guineensis chromosome arms. The probes were able to identify individual homoeologous chromosome regions in the related Arecaceae palm species: American oil palm (Elaeis oleifera), date palm (Phoenix dactylifera) and coconut (Cocos nucifera) showing the comparative organization and concerted evolution of genomes in the Arecaceae. The oligonucleotide probes developed here provide a valuable approach to chromosome arm identification and allow tracking chromosome transfer in hybridization and breeding programs in oil palm, as well as comparative studies within Arecaceae.


Assuntos
Arecaceae , Arecaceae/genética , Cromossomos , Hibridização Genética , Hibridização in Situ Fluorescente , Oligonucleotídeos
17.
Br J Sports Med ; 56(12): 692-700, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35168956

RESUMO

OBJECTIVE: To determine how well exercise interventions are reported in trials in health and disease. DESIGN: Overview of systematic reviews. DATA SOURCES: PubMed, EMBASE, CINAHL, SPORTDiscus and PsycINFO from inception until June 2021. ELIGIBILITY CRITERIA: Reviews of any health condition were included if they primarily assessed quality of exercise intervention reporting using the Consensus on Exercise Reporting Template (CERT) or the Template for Intervention Description and Replication (TIDieR). We assessed review quality using a modified version of A MeaSurement Tool to Assess systematic Reviews. RESULTS: We identified 7804 studies and included 28 systematic reviews. The median (IQR) percentage of CERT and TIDieR items appropriately reported was 24% (19%) and 49% (33%), respectively. TIDieR items 1, Brief name (median=100%, IQR 4) and 2, Why (median=98%, IQR 6), as well as CERT item 4, Supervision and delivery (median=68%, IQR 89), were the best reported. For replication of exercise interventions, TIDieR item 8, When and how much, was moderately well reported (median=62%, IQR 68) although CERT item 8, Description of each exercise to enable replication (median=23%, IQR 44) and item 13, Detailed description of the exercise intervention (median=24%, IQR 66) were poorly reported. Quality of systematic reviews ranged from moderate to critically low quality. CONCLUSION: Exercise interventions are poorly reported across a range of health conditions. If exercise is medicine, then how it is prescribed and delivered is unclear, potentially limiting its translation from research to practice. PROSPERO REGISTRATION NUMBER: CRD42021261285; Open Science Framework: osf.io/my3ec/.


Assuntos
Terapia por Exercício , Medicina , Consenso , Exercício Físico , Humanos , Revisões Sistemáticas como Assunto
18.
Nano Lett ; 21(12): 5386-5393, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34061548

RESUMO

Plasmonic structures confine electromagnetic energy at the nanoscale, resulting in local, inhomogeneous, controllable heating, but reading out the temperature using optical techniques poses a difficult challenge. Here, we report on the optical thermometry of individual gold nanorod trimers that exhibit multiple wavelength-dependent plasmon modes resulting in measurably different local temperature distributions. Specifically, we demonstrate how photothermal microscopy encodes different wavelength-dependent temperature profiles in the asymmetry of the photothermal image point spread function. These asymmetries are interpreted through companion numerical simulations to reveal how thermal gradients within the trimer can be controlled by exciting its hybridized plasmon modes. We also find that plasmon modes that are optically dark can be excited by focused laser beam illumination, providing another route to modify thermal profiles beyond wide-field illumination. Taken together these findings demonstrate an all-optical thermometry technique to actively create and measure nanoscale thermal gradients below the diffraction limit.


Assuntos
Nanotubos , Termometria , Diagnóstico por Imagem , Ouro , Temperatura
19.
Int J Mol Sci ; 23(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36430666

RESUMO

Despite intense research into the multifaceted etiology of neurodegenerative diseases (ND), they remain incurable. Here we provide a brief overview of several major ND and explore novel therapeutic approaches. Although the cause (s) of ND are not fully understood, the accumulation of misfolded/aggregated proteins in the brain is a common pathological feature. This aggregation may initiate disruption of Ca++ signaling, which is an early pathological event leading to altered dendritic structure, neuronal dysfunction, and cell death. Presently, ND gene therapies remain unidimensional, elusive, and limited to modifying one pathological feature while ignoring others. Considering the complexity of signaling cascades in ND, we discuss emerging therapeutic concepts and suggest that deciphering the molecular mechanisms involved in dendritic pathology may broaden the phenotypic spectrum of ND treatment. An innovative multiplexed gene transfer strategy that employs silencing and/or over-expressing multiple effectors could preserve vulnerable neurons before they are lost. Such therapeutic approaches may extend brain health span and ameliorate burdensome chronic disease states.


Assuntos
Cálcio , Doenças Neurodegenerativas , Humanos , Cálcio/metabolismo , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/terapia , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Cálcio da Dieta , Terapia Genética
20.
J Emerg Nurs ; 48(5): 504-514, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35667891

RESUMO

INTRODUCTION: Urban ED patients have elevated rates of substance use and intimate partner violence. The purpose of this study is to describe the risk profiles for intimate partner violence among urban ED patients who report at-risk alcohol use only, cannabis use only, or both types of substance use. METHODS: Cross-sectional survey data were collected from study participants (N = 1037; 53% female; ages 18-50) following informed consent. We measured participants' past-year at-risk drinking (women/men who had 4+/5+ drinks in a day), cannabis use, psychosocial and demographic characteristics, and past-year physical intimate partner violence (assessed with the Revised Conflict Tactics Scale). We used bivariate analysis to assess whether rates of intimate partner violence perpetration and victimization differed by type of substance use behavior. Multivariate logistic regression models were estimated for each intimate partner violence outcome. All analyses were stratified by gender. RESULTS: Rates of intimate partner violence differed significantly by type of substance use behavior and were highest among those who reported both at-risk drinking and cannabis use. Multivariate analysis showed that women who reported at-risk drinking only, cannabis use only, or both types of substance use had increased odds for intimate partner violence perpetration and victimization compared with women who reported neither type of substance use. Men's at-risk drinking and cannabis use were not associated with elevated odds of intimate partner violence perpetration or victimization. DISCUSSION: Brief screening of patients' at-risk drinking and cannabis use behaviors may help identify those at greater risk for intimate partner violence and those in need of referral to treatment.


Assuntos
Cannabis , Vítimas de Crime , Violência por Parceiro Íntimo , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
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