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Identifying and protecting hotspots of endemism and species richness is crucial for mitigating the global biodiversity crisis. However, our understanding of spatial diversity patterns is far from complete, which severely limits our ability to conserve biodiversity hotspots. Here, we report a comprehensive analysis of amphibian species diversity in China, one of the most species-rich countries on Earth. Our study combines 20 y of field surveys with new molecular analyses of 521 described species and also identifies 100 potential cryptic species. We identify 10 hotspots of amphibian diversity in China, each with exceptional species richness and endemism and with exceptional phylogenetic diversity and phylogenetic endemism (based on a new time-calibrated, species-level phylogeny for Chinese amphibians). These 10 hotspots encompass 59.6% of China's described amphibian species, 49.0% of cryptic species, and 55.6% of species endemic to China. Only four of these 10 hotspots correspond to previously recognized biodiversity hotspots. The six new hotspots include the Nanling Mountains and other mountain ranges in South China. Among the 186 species in the six new hotspots, only 9.7% are well covered by protected areas and most (88.2%) are exposed to high human impacts. Five of the six new hotspots are under very high human pressure and are in urgent need of protection. We also find that patterns of richness in cryptic species are significantly related to those in described species but are not identical.
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Anfíbios , Biodiversidade , Filogenia , Animais , Anfíbios/classificação , China , Conservação dos Recursos NaturaisRESUMO
Soil salinity significantly limits rice productivity, but it is poorly understood how excess sodium (Na+) is delivered to the grains at the reproductive stage. Here, we functionally characterized OsHAK4, a member of the clade IV HAK/KUP/KT transporter subfamily in rice. OsHAK4 was localized to the plasma membrane and exhibited influx transport activity for Na+, but not for K+. Analysis of organ- and growth stage-dependent expression patterns showed that very low expression levels of OsHAK4 were detected at the vegetative growth stage, but its high expression in uppermost node I, peduncle, and rachis was found at the reproductive stage. Immunostaining indicated OsHAK4 localization in the phloem region of node I, peduncle, and rachis. Knockout of OsHAK4 did not affect the growth and Na+ accumulation at the vegetative stage. However, at the reproductive stage, the hak4 mutants accumulated higher Na+ in the peduncle, rachis, husk, and brown rice compared to the wild-type rice. Element imaging revealed higher Na+ accumulation at the phloem region of the peduncle in the mutants. These results indicate that OsHAK4 plays a crucial role in retrieving Na+ from the phloem in the upper nodes, peduncle, and rachis, thereby preventing Na+ distribution to the grains at the reproductive stage of rice.
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Regulação da Expressão Gênica de Plantas , Oryza , Floema , Proteínas de Plantas , Sódio , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Floema/metabolismo , Floema/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Sódio/metabolismo , Reprodução , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/genéticaRESUMO
Defense against ultraviolet (UV) radiation exposure is essential for survival, especially in high-elevation species. Although some specific genes involved in UV response have been reported, the full view of UV defense mechanisms remains largely unexplored. Herein, we used integrated approaches to analyze UV responses in the highest-elevation frog, Nanorana parkeri. We show less damage and more efficient antioxidant activity in skin of this frog than those of its lower-elevation relatives after UV exposure. We also reveal genes related to UV defense and a corresponding temporal expression pattern in N. parkeri. Genomic and metabolomic analysis along with large-scale transcriptomic profiling revealed a time-dependent coordinated defense mechanism in N. parkeri. We also identified several microRNAs that play important regulatory roles, especially in decreasing the expression levels of cell cycle genes. Moreover, multiple defense genes (i.e., TYR for melanogenesis) exhibit positive selection with function-enhancing substitutions. Thus, both expression shifts and gene mutations contribute to UV adaptation in N. parkeri. Our work demonstrates a genetic framework for evolution of UV defense in a natural environment.
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Anuros , Raios Ultravioleta , Animais , Anuros/genética , Pele , Perfilação da Expressão Gênica , AntioxidantesRESUMO
Field biology is an area of research that involves working directly with living organisms in situ through a practice known as "fieldwork." Conducting fieldwork often requires complex logistical planning within multiregional or multinational teams, interacting with local communities at field sites, and collaborative research led by one or a few of the core team members. However, existing power imbalances stemming from geopolitical history, discrimination, and professional position, among other factors, perpetuate inequities when conducting these research endeavors. After reflecting on our own research programs, we propose four general principles to guide equitable, inclusive, ethical, and safe practices in field biology: be collaborative, be respectful, be legal, and be safe. Although many biologists already structure their field programs around these principles or similar values, executing equitable research practices can prove challenging and requires careful consideration, especially by those in positions with relatively greater privilege. Based on experiences and input from a diverse group of global collaborators, we provide suggestions for action-oriented approaches to make field biology more equitable, with particular attention to how those with greater privilege can contribute. While we acknowledge that not all suggestions will be applicable to every institution or program, we hope that they will generate discussions and provide a baseline for training in proactive, equitable fieldwork practices.
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Temas Bioéticos , Biologia , Biologia/ética , HumanosRESUMO
Amphibians represent a diverse group of tetrapods, marked by deep divergence times between their three systematic orders and families. Studying amphibian biology through the genomics lens increases our understanding of the features of this animal class and that of other terrestrial vertebrates. The need for amphibian genomic resources is more urgent than ever due to the increasing threats to this group. Amphibians are one of the most imperiled taxonomic groups, with approximately 41% of species threatened with extinction due to habitat loss, changes in land use patterns, disease, climate change, and their synergistic effects. Amphibian genomic resources have provided a better understanding of ontogenetic diversity, tissue regeneration, diverse life history and reproductive modes, anti-predator strategies, and resilience and adaptive responses. They also serve as essential models for studying broad genomic traits, such as evolutionary genome expansions and contractions, as they exhibit the widest range of genome sizes among all animal taxa and possess multiple mechanisms of genetic sex determination. Despite these features, genome sequencing of amphibians has significantly lagged behind that of other vertebrates, primarily due to the challenges of assembling their large, repeat-rich genomes and the relative lack of societal support. The emergence of long-read sequencing technologies, combined with advanced molecular and computational techniques that improve scaffolding and reduce computational workloads, is now making it possible to address some of these challenges. To promote and accelerate the production and use of amphibian genomics research through international coordination and collaboration, we launched the Amphibian Genomics Consortium (AGC, https://mvs.unimelb.edu.au/amphibian-genomics-consortium ) in early 2023. This burgeoning community already has more than 282 members from 41 countries. The AGC aims to leverage the diverse capabilities of its members to advance genomic resources for amphibians and bridge the implementation gap between biologists, bioinformaticians, and conservation practitioners. Here we evaluate the state of the field of amphibian genomics, highlight previous studies, present challenges to overcome, and call on the research and conservation communities to unite as part of the AGC to enable amphibian genomics research to "leap" to the next level.
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Anfíbios , Genômica , Animais , Anfíbios/genética , Genômica/métodos , Conservação dos Recursos Naturais/métodos , GenomaRESUMO
The development of high-energy-density cathode materials is regarded as the ultimate goal of alkali metal-ion batteries energy storage. However, the strategy of regulating specific capacity is limited by the theoretical capacity, and meanwhile focusing on improving capacity will lead to structural destructions. Herein, a novel perspective is proposed that tuning the electronic band structure by introducing highly electronegative fluoride atoms in NaxTMO2-yFy (0 < x < 1, 0 < y < 2) model compounds to improve redox potential for developing high-energy-density layered oxides. Highly electronegative fluoride atoms is introduced into P2-type Na0.67Fe0.5Mn0.5O2 (NFM), and the thus fluoride NFM (F-NFM) cathode achieved high redox potential (3.0 V) and high energy density (446 Wh kg-1). Proved by structural characterizations, fluorine atoms are successfully incorporated into oxygen sites in NFM lattice. Ultraviolet photoelectron spectroscopy is applied to quantitatively analyze the improved redox potential of F-NFM, which is achieved by the decreased valence band energy in electronic band structure due to the strongly electrophilic fluoride ions. Moreover, fluoride atoms can stabilize the local environment of NFM and improve its redox potential. The work provides a perspective to improve redox potential by tuning the electronic band structure in layered oxides and developing high-energy-density alkali metal-ion batteries.
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The genus Sylvirana includes 12 species widely distributed in South China and Southeast Asia. The phylogenetic relationships and species diversity for Sylvirana and allied genera remain unresolved and controversial due to insufficient data and incomplete taxon sampling. Using a combined dataset of mitochondrial genes (16S and COI) and 101 nuclear genes obtained through the amplicon sequence capture approach, we generated the most comprehensive phylogenetic analysis for the genus Sylvirana to date, inferring diversity, phylogenetic relationships, and historical biogeography with unprecedented levels of taxon and geographic sampling. Our results conservatively reveal six undescribed species, mostly distributed in peninsular Indochina. Phylogenetic analyses strongly support the non-monophyly of Sylvirana with respect to Pterorana. Additionally, phylogenetic results place Sylvirana guentheri and Pelophylax lateralis into genus Humerana, supporting the inclusion of Hylarana latouchii, Papurana milleti, and Hylarana attigua within Pteroranaâ¯+â¯Sylvirana. The long-disputed species of Hylarana bannanica (previously Sylvirana) cluster with genus Papurana. Because the results of multiple non-monophyletic genera create taxonomic confusion, we suggest relegating all genera to subgenus rank of Hylarana. Sylvirana is a junior synonym of the Pterorana. Biogeographically, we trace the origin of Pterorana to Southeast Asia during the early Miocene, with subsequent dispersal thereafter. Our study shows that climatic changes may have profoundly influenced the diversification of Pterorana during the Miocene.
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Currently, the standard treatment for patients who have undergone percutaneous coronary intervention (PCI) following acute myocardial infarction (MI) involves dual antiplatelet therapy (DAPT) with a combination of aspirin and a potent P2Y12 receptor inhibitor. However, the potential benefits of aspirin were partially constrained by the intolerance of some patients. The safety and efficacy of indobufen, an alternative antiplatelet agents to aspirin, in patients with AMI after PCI are yet to be thoroughly investigated.This retrospective study was conducted at a single center and utilized propensity score matching. The enrollment spanned from January 2019 to June 2022, incorporating patients with AMI after PCI. The participants were categorized into two groups based on discharged prescriptions: the aspirin DAPT group and the indobufen DAPT group. The primary endpoint focused on net adverse clinical event (NACE), defined as a composite outcome, including cardiac death, recurrence of MI, definite or probable stent thrombosis (ST), target lesion revascularization (TLR), ischemic stroke and Bleeding Academic Research Consortium (BARC) criteria type 2, 3, or 5. All the patients underwent a one-year follow-up period.A total of 1451 patients were enrolled in this study, with 258 assigned to the indobufen DAPT group and 1193 to the aspirin DAPT group. Following 1:1 propensity score matching, 224 patients were retained in each group. In the indobufen DAPT group, 58 individuals (25.9%) experienced the primary endpoint within one year, compared to 52 individuals (23.2%) in the aspirin DAPT group (HR 1.128, 95% CI 0.776-1.639, p = .527). Specifically, no significant differences were observed in either the efficacy endpoint (MACCE, 20.1% vs. 14.7%, HR 1.392, 95% CI 0.893-2.170, p = .146) or the safety endpoint (BARC 2,3 or 5, 8.04% vs. 10.30%, HR 0.779, p = .427). These findings remained consistent at 1, 3, or 6 months. Additionally, the incidence of gastrointestinal symptoms were significantly lower in indobufen DAPT group compared to the aspirin DAPT group (7.1% vs. 14.3%, p = .022).Our research reveals that the efficacy and safety of indobufen are comparable to aspirin in Chinese patients with AMI following PCI. Given the potential advantages of indobufen in alleviating gastrointestinal symptoms, we propose it as a viable alternative for individuals intolerant to aspirin.
What is the context? Currently, the standard treatment for patients who have undergone percutaneous coronary intervention following acute myocardial infarction involves dual antiplatelet therapy with a combination of aspirin and a potent P2Y12 receptor inhibitor.However, the potential benefits of aspirin were partially constrained by the intolerance of some patients.The safety and efficacy of indobufen, an alternative antiplatelet agents to aspirin, in patients with AMI after PCI are yet to be thoroughly investigated.What is new? While both American and European clinical guidelines recommend the use of indobufen as an alternative treatment for patients who cannot tolerate aspirin, there exists a limited body of research on this subject.Our research is the first to address this gap by comparing the efficacy and safety of indobufen and aspirin in patients with AMI.Our research reveals that the efficacy and safety of indobufen are comparable to aspirin in Chinese patients with AMI following PCI. Given the potential advantages of indobufen in alleviating gastrointestinal symptoms, we propose it as a viable alternative for individuals intolerant to aspirin.What is the impact? These findings might pave the way for further exploration of alternatives to aspirin in patients with AMI.
Assuntos
Aspirina , Clopidogrel , Infarto do Miocárdio , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/métodos , Aspirina/uso terapêutico , Masculino , Feminino , Clopidogrel/uso terapêutico , Pessoa de Meia-Idade , Estudos Retrospectivos , Inibidores da Agregação Plaquetária/uso terapêutico , Inibidores da Agregação Plaquetária/farmacologia , Idoso , Resultado do Tratamento , Quimioterapia Combinada/métodosRESUMO
Speciation plays a central role in evolutionary studies, and particularly how reproductive isolation (RI) evolves. The origins and persistence of RI are distinct processes that require separate evaluations. Treating them separately clarifies the drivers of speciation and then it is possible to link the processes to understand large-scale patterns of diversity. Recent genomic studies have focused predominantly on how species or RI originate. However, we know little about how species persist in face of gene flow. Here, we evaluate a contact zone of two closely related toad-headed lizards (Phrynocephalus) using a chromosome-level genome assembly and population genomics. To some extent, recent asymmetric introgression from Phrynocephalus putjatai to P. vlangalii reduces their genomic differences. However, their highly divergent regions (HDRs) have heterogeneous distributions across the genomes. Functional gene annotation indicates that many genes within HDRs are involved in reproduction and RI. Compared with allopatric populations, contact areas exhibit recent divergent selection on the HDRs and a lower population recombination rate. Taken together, this implies that divergent selection and low genetic recombination help maintain RI. This study provides insights into the genomic mechanisms that drive RI and two species persistence in the face of gene flow during the late stage of speciation.
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Genética Populacional , Lagartos , Animais , Fluxo Gênico , Especiação Genética , Hibridização Genética , Lagartos/genética , Recombinação Genética , Isolamento ReprodutivoRESUMO
Rice grain is a poor dietary source of zinc (Zn) but the primary source of cadmium (Cd) for humans; however, the molecular mechanisms for their accumulation in rice grain remain incompletely understood. This study functionally characterized a tonoplast-localized transporter, OsMTP1. OsMTP1 was preferentially expressed in the roots, aleurone layer, and embryo of seeds. OsMTP1 knockout decreased Zn concentration in the root cell sap, roots, aleurone layer and embryo, and subsequently increased Zn concentration in shoots and polished rice (endosperm) without yield penalty. OsMTP1 haplotype analysis revealed elite alleles associated with increased Zn level in polished rice, mostly because of the decreased OsMTP1 transcripts. OsMTP1 expression in yeast enhanced Zn tolerance but did not affect that of Cd. While OsMTP1 knockout resulted in decreased uptake, translocation and accumulation of Cd in plant and rice grain, which could be attributed to the indirect effects of altered Zn accumulation. Our results suggest that rice OsMTP1 primarily functions as a tonoplast-localized transporter for sequestrating Zn into vacuole. OsMTP1 knockout elevated Zn concentration but prevented Cd deposition in polished rice without yield penalty. Thus, OsMTP1 is a candidate gene for enhancing Zn level and reducing Cd level in rice grains.
Assuntos
Oryza , Zinco , Humanos , Zinco/metabolismo , Cádmio/metabolismo , Oryza/metabolismo , Vacúolos/metabolismo , Raízes de Plantas/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Grão Comestível/metabolismoRESUMO
Although numerous studies on the impacts of climate change on biodiversity have been published, only a handful are focused on the intraspecific level or consider population-level models (separate models per population). We endeavored to fill this knowledge gap relative to the Qinghai-Tibetan plateau (QTP) by combining species distribution modeling (SDMs) with population genetics (i.e., population-level models) and phylogenetic methods (i.e., phylogenetic tree reconstruction and phylogenetic diversity analyses). We applied our models to 11 endemic and widely distributed herpetofauna species inhabiting high elevations in the QTP. We aimed to determine the influence of environmental heterogeneity on species' responses to climate change, the magnitude of climate-change impacts on intraspecific diversity, and the relationship between species range loss and intraspecific diversity losses under 2 shared socioeconomic pathways (SSP245 and SSP585) and 3 future periods (2050s, 2070s, and 2090s). The effects of global climatic change were more pronounced at the intraspecific level (22% of haplotypes lost and 36% of populations lost) than the morphospecies level in the SSP585 climate change scenario. Maintenance of genetic diversity was in general determined by a combination of factors including range changes, species genetic structure, and the part of the range predicted to be lost. This is owing to the fact that the loss and survival of populations were observed in species irrespective of the predicted range changes (contraction or expansion). In the southeast (mountainous regions), climate change had less of an effect on range size (>100% in 3 species) than in central and northern QTP plateau regions (range size <100% in all species). This may be attributed to environmental heterogeneity, which provided pockets of suitable climate in the southeast, whereas ecosystems in the north and central regions were homogeneous. Generally, our results imply that mountainous regions with high environmental heterogeneity and high genetic diversity may buffer the adverse impacts of climate change on species distribution and intraspecific diversity. Therefore, genetic structure and characteristics of the ecosystem may be crucial for conservation under climate change.
Impactos del cambio climático sobre la diversidad de herpetofauna en la meseta Qinghai-Tíbet Región Aunque se han publicado numerosos estudios sobre los impactos del cambio climática en la biodiversidad, son muy pocos los que se enfocan en el nivel intraespecífico o que consideran modelos a nivel poblacional (modelos separados por población). Intentamos cerrar este vacío de conocimiento en relación con la meseta Qinghai-Tíbet (MQT) con la combinación entre modelos de distribución de especies (MDE) y genética poblacional (modelos a nivel poblacional) y métodos filogenéticos (reconstrucción de árboles filogenéticos y análisis de diversidad filogenética). Aplicamos nuestros modelos a once especies endémicas de herpetofauna con distribución amplia en las elevaciones más altas de la MQT. Nos planteamos determinar la influencia de la heterogeneidad de las especies sobre la respuesta de las especies al cambio climático, la magnitud de los impactos del cambio climático sobre la diversidad intraespecífica y la relación entre la pérdida de distribución de la especie y las pérdidas de diversidad intraespecífica bajo dos vías socioeconómicas (SSP245 y SSP585) y tres periodos del futuro (2050s, 2070s y 2090s). Los efectos del cambio climático global fueron más pronunciados a nivel intraespecífico (22% de pérdida en los haplotipos y 36% en las poblaciones) que al nivel morfoespecie en el escenario de cambio climático SSP585. El mantenimiento de la diversidad genética casi siempre estuvo determinado por una combinación de factores que incluyen cambios en la distribución, estructura genética de las especies y la parte de la distribución que se pronosticó se perdería. Esto se debe a que observamos la pérdida y supervivencia de las poblaciones sin importar los cambios pronosticados en la distribución (contracción o expansión). En las regiones montañosas del sureste, el cambio climático tuvo un efecto menor sobre la distribución (>100% en tres especies) comparado con las regiones de la meseta central y del norte de la MQT (distribución <100% en todas las especies). Esto puede atribuirse a la heterogeneidad ambiental, la cual proporciona recovecos de clima adecuado en el sureste, mientras que los ecosistemas en las regiones central y norte fueron homogéneos. De manera general, nuestros resultados implican que las regiones montañosas con una elevada heterogeneidad ambiental y una gran diversidad genética podrían reducir los impactos adversos del cambio climático sobre la distribución de las especies y la diversidad intraespecífica. Por lo tanto, la estructura genética y las características del ecosistema pueden ser cruciales para conservar bajo el cambio climático.
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Mudança Climática , Ecossistema , Tibet , Filogenia , Conservação dos Recursos NaturaisRESUMO
BACKGROUND: To report three cases of autoimmune cerebellar ataxia related to anti-delta/notch-like epidermal growth factor-related receptor (Tr/DNER) antibodies. CASE PRESENTATION: Patients with unknown cerebellar ataxia were screened with autoimmune cerebellar ataxia (ACA)-related antibody panel. The anti-Tr antibody was positive in three female patients in whom the onset ages were 43 years, 35 years and 43 years old. The antibody titres of serum and cerebrospinal fluid were all 1:32. Cerebral ataxia was the most prominent presentation. Mild cerebellar atrophy was found in one of the patients. Immunotherapy was effective in all three patients. CONCLUSION: The Tr antibody is associated with autoimmune ataxia, and it has been suggested that the anti-Tr antibody should be tested in patients with cerebellar ataxia who are negative for routine ACA antibodies. Early immunotherapy may improve patient prognoses.
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Ataxia Cerebelar , Humanos , Feminino , Adulto , Autoanticorpos , Imunoterapia , Proteínas do Tecido Nervoso , Receptores de Superfície CelularRESUMO
Tiller number is one of the most important agronomic traits that determine rice (Oryza sativa) yield. Active growth of tiller bud (TB) requires high amount of mineral nutrients; however, the mechanism underlying the distribution of mineral nutrients to TB with low transpiration is unknown. Here, we found that the distribution of Zn to TB is mediated by OsZIP4, one of the ZIP (ZRT, IRT-like protein) family members. The expression of OsZIP4 was highly detected in TB and nodes, and was induced by Zn deficiency. Immunostaining analysis revealed that OsZIP4 was mainly expressed in phloem of diffuse vascular bundles in the nodes and the axillary meristem. The mutation of OsZIP4 did not affect the total Zn uptake, but altered Zn distribution; less Zn was delivered to TB and new leaf, but more Zn was retained in the basal stems at the vegetative growth stage. Bioimaging analysis showed that the mutant aberrantly accumulated Zn in enlarged and transit vascular bundles of the basal node, whereas in wild-type high accumulation of Zn was observed in the meristem part. At the reproductive stage, mutation of OsZIP4 resulted in delayed panicle development, which is associated with decreased Zn distribution to the panicles. Collectively, OsZIP4 is involved in transporting Zn to the phloem of diffuse vascular bundles in the nodes for subsequent distribution to TBs and other developing tissues. It also plays a role in transporting Zn to meristem cells in the TBs.
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Proteínas de Transporte de Cátions/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Zinco/metabolismo , Transporte Biológico , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica de Plantas , Mutação , Oryza/crescimento & desenvolvimento , Fenótipo , Floema/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/crescimento & desenvolvimento , Distribuição Tecidual , Zinco/farmacocinética , Isótopos de Zinco/farmacocinéticaRESUMO
Molecular phylogenies have yielded strong support for many parts of the amphibian Tree of Life, but poor support for the resolution of deeper nodes, including relationships among families and orders. To clarify these relationships, we provide a phylogenomic perspective on amphibian relationships by developing a taxon-specific Anchored Hybrid Enrichment protocol targeting hundreds of conserved exons which are effective across the class. After obtaining data from 220 loci for 286 species (representing 94% of the families and 44% of the genera), we estimate a phylogeny for extant amphibians and identify gene tree-species tree conflict across the deepest branches of the amphibian phylogeny. We perform locus-by-locus genealogical interrogation of alternative topological hypotheses for amphibian monophyly, focusing on interordinal relationships. We find that phylogenetic signal deep in the amphibian phylogeny varies greatly across loci in a manner that is consistent with incomplete lineage sorting in the ancestral lineage of extant amphibians. Our results overwhelmingly support amphibian monophyly and a sister relationship between frogs and salamanders, consistent with the Batrachia hypothesis. Species tree analyses converge on a small set of topological hypotheses for the relationships among extant amphibian families. These results clarify several contentious portions of the amphibian Tree of Life, which in conjunction with a set of vetted fossil calibrations, support a surprisingly younger timescale for crown and ordinal amphibian diversification than previously reported. More broadly, our study provides insight into the sources, magnitudes, and heterogeneity of support across loci in phylogenomic data sets.[AIC; Amphibia; Batrachia; Phylogeny; gene tree-species tree discordance; genomics; information theory.].
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Fósseis , Genômica , Animais , Anuros , Humanos , FilogeniaRESUMO
PURPOSE: Methicillin-resistant Staphylococcus aureus (MRSA) infection at impaired wound is associated with high risks of developing to persistent bacterial infections since bacterial biofilm is easy to form in MRSA infected wounds. An advanced therapeutic approach to effectively penetrate and eliminate bacterial biofilm and to accelerate cell proliferation and migration at the wound is crucial. METHODS: The poly(ε-caprolactone)-monomethoxyl poly (ethylene glycol) (PCL-mPEG) micelles loaded with Quercetin and Rifampicin (QRMs) were prepared. Bacterial biofilm proliferation and elimination effect of QRMs were evaluated with confocal laser scanning microscopy. Antibacterial assay was further performed to detect antibacterial activity and mechanism. The cell scratch assay and cellular uptake were performed in HaCaT skin epithelial cells. RESULTS: Our results showed that the small sized QRMs could penetrate the interior of MRSA biofilm to disperse and eradicate biofilm. Then, antibiotics are released and accumulated in the acidic biofilm environment. QRMs could kill bacteria through increasing bacterial membrane permeability and altering membrane potential and membrane fluidity. Moreover, QRMs improved intracellular and cytoplasmic delivery efficiency of drugs to epithelial cells, and in the scratch test, presented a stronger ability to promote migration and proliferation of HaCaT cells compared with free drugs. Hemolysis test further proved good biocompatibility of QRMs. CONCLUSIONS: QRMs could potentially be used as a novel dual-functional nanotherapeutic for anti-bacterial infection by eradicating biofilm and accelerating cells proliferation at MRSA infected wound.
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Infecções Bacterianas , Staphylococcus aureus Resistente à Meticilina , Infecção dos Ferimentos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Biofilmes , Humanos , Concentração de Íons de Hidrogênio , Micelas , Testes de Sensibilidade Microbiana , Infecção dos Ferimentos/tratamento farmacológicoRESUMO
Viviparous (live-bearing) vertebrates have evolved repeatedly within otherwise oviparous (egg-laying) clades. Over two-thirds of these changes in vertebrate reproductive parity mode happened in squamate reptiles, where the transition has happened between 98 and 129 times. The transition from oviparity to viviparity requires numerous physiological, morphological, and immunological changes to the female reproductive tract, including eggshell reduction, delayed oviposition, placental development for supply of water and nutrition to the embryo by the mother, enhanced gas exchange, and suppression of maternal immune rejection of the embryo. We performed genomic and transcriptomic analyses of a closely related oviparous-viviparous pair of lizards (Phrynocephalus przewalskii and Phrynocephalus vlangalii) to examine these transitions. Expression patterns of maternal oviduct through reproductive development of the egg and embryo differ markedly between the two species. We found changes in expression patterns of appropriate genes that account for each of the major aspects of the oviparity to viviparity transition. In addition, we compared the gene sequences in transcriptomes of four oviparous-viviparous pairs of lizards in different genera (Phrynocephalus, Eremias, Scincella, and Sphenomorphus) to look for possible gene convergence at the sequence level. We discovered low levels of convergence in both amino acid replacement and evolutionary rate shift. This suggests that most of the changes that produce the oviparity-viviparity transition are changes in gene expression, so occasional reversals to oviparity from viviparity may not be as difficult to achieve as has been previously suggested.
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Evolução Molecular , Oviparidade/genética , Transcriptoma/genética , Viviparidade não Mamífera/genética , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Genômica , Lagartos/genética , Lagartos/crescimento & desenvolvimento , Filogenia , Placentação/genética , Gravidez , Reprodução/genética , Serpentes/genética , Serpentes/crescimento & desenvolvimentoRESUMO
Iron (Fe) from rice grains is an important source of dietary intake; however, the molecular mechanisms responsible for loading of Fe to the grains are poorly understood. We functionally characterized a vacuolar iron transporter gene, OsVIT2 in terms of expression pattern, cellular localization, and mutant phenotypes. OsVIT2 was expressed in the parenchyma cell bridges of nodes, in the mestome sheath of leaf sheath and aleurone of the caryopsis. Mutation of OsVIT2 resulted in decreased Fe distribution to the leaf sheath, nodes, and aleurone, but increased Fe to the leaf blade and grains. Furthermore, Fe was heavily deposited in the parenchyma cell bridges, mestome sheath and aleurone in the wild-type rice, but this accumulation was decreased in the knockout lines. Conversely, heavier deposition of Fe was observed in the embryo and endosperm of the grains of knockout lines compared with the wild-type rice, resulting in increased Fe accumulation in the polished rice without yield penalty. These results indicate that OsVIT2 is involved in the distribution of Fe to the grains through sequestering Fe into vacuoles in mestome sheath, nodes, and aleurone layer and that knockout of this gene provides a potential way for Fe biofortification without yield penalty.
Assuntos
Oryza , Regulação da Expressão Gênica de Plantas , Ferro/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Oryza/genética , Oryza/metabolismo , Vacúolos/metabolismoRESUMO
Montane frogs of the genus Quasipaa Dubois, 1992 occur from southern China to Southeast Asia (Frost 2021). Analyses of mtDNA (Cytb) and nuDNA data (Rag1, Rag2, Rhod, Tyr) for samples from 93 localities throughout its distribution yield a phylogeny. Clades A and B occur in Southeast Asia, clade C in northern Yangtze River, China, clade D in southwestern China, and clades E and F in southeastern China. Results place Q. yei within monophyletic Quasipaa and identify two new species. Based on nuDNA data, the basal split of clade A and B indicates an Indochinese origin of Quasipaa. The west-east diversification of five species across South China (Q. spinosa, Q. exilispinosa, Q. jiulongensis, Q. shini, Q. boulengeri) corresponds to topographic terrains II and III of China. Divergence of species from southeastern China (Q. shini, Q. jiulongensis, Q. spinosa, Q. exilispinosa) and southwestern China (Q. boulengeri) dates to 15.30-16.56 Ma (million years ago). A principal component analysis (PCA) and t-test involving 19 bioclimatic variables identifies significantly different environmental conditions between the two regions. Species' distribution models (SDM) for Q. spinosa and Q. boulengeri identify the best areas to be eastern and western South China, respectively. Thus, environmental variation appears to have influenced the genetic divergence and distributions of Quasipaa in South China. Mito-nuclear discordance indicates that some individuals of Q. exilispinosa and Q. spinosa hybridized historically.
Assuntos
Anuros , DNA Mitocondrial , Animais , Anuros/genética , Núcleo Celular , China , DNA Mitocondrial/genética , Humanos , FilogeniaRESUMO
Emerging infectious diseases are on the rise in many different taxa, including, among others, the amphibian batrachochytrids, the snake fungal disease and the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) virus, responsible for Coronavirus disease 2019 (COVID-19) in mammals. Following the onset of the pandemic linked to COVID-19, eastern Asia has shown strong leadership, taking actions to regulate the trade of potential vector species in several regions. These actions were taken in response to an increase in public awareness, and the need for a quick reaction to mitigate against further pandemics. However, trade restrictions rarely affect amphibians, despite the risk of pathogen transmission, directly, or indirectly through habitat destruction and the loss of vector consumption. Thus, species that help alleviate the risk of zoonoses or provide biological control are not protected. Hence, in view of the global amphibian decline and the risk of zoonoses, we support the current wildlife trade regulations and support measures to safeguard wildlife from overexploitation. The current period of regulation overhaul should be used as a springboard for amphibian conservation. To mitigate risks, we suggest the following stipulations specifically for amphibians. I) Restrictions to amphibian farming in eastern Asia, in relation to pathogen transmission and the establishment of invasive species. II) Regulation of the amphibian pet trade, with a focus on potential vector species. III) Expansion of the wildlife trade ban, to limit the wildlife-human-pet interface. The resulting actions will benefit both human and wildlife populations, as they will lead to a decrease in the risk of zoonoses and better protection of the environment. SIGNIFICANCE STATEMENT: There is an increasing number of emerging infectious diseases impacting all species, including amphibians, reptiles and mammals. The latest threat to humans is the virus responsible for COVID-19, and the resulting pandemic. Countries in eastern Asia have taken steps to regulate wildlife trade and prevent further zoonoses thereby decreasing the risk of pathogens arising from wild species. However, as amphibians are generally excluded from regulations we support specific trade restrictions: I) Restrictions to amphibian farming; II) regulation of the amphibian pet trade; III) expansion of the wildlife trade ban. These restrictions will benefit both human and wildlife populations by decreasing the risks of zoonoses and better protecting the environment.
RESUMO
BACKGROUND Hydration remains the mainstay of contrast-induced nephropathy (CIN) prevention, and new biomarkers of cystatin C (Cys C) and neutrophil gelatinase-associated lipocalin (NGAL) have been suggested. This study aimed to explore whether hydration is essential in patients with very low-risk profiles of CIN who are undergoing coronary angiography. MATERIAL AND METHODS A total of 150 patients were enrolled and randomly distributed to 3 groups: the Preventive Group (n=50, saline hydration was given 6 h before the procedure until 12 h after the procedure), the Remedial Group (n=50, saline hydration was given after procedure for 12 h), and the No Hydration (NH) group (n=50, saline was only given during the procedure). Serum creatinine (Cr), Cys C, and urinary NGAL were tested 3 times at different times. RESULTS Six patients were excluded because of Mehran risk score >2. There was no CIN among 144 individuals. At 24 h and at 72 h after the procedure, we found no significant differences in the levels of Cr and Cys C (0.72±0.11 mg/L for the Preventive Group, 0.67±0.14 mg/L for the Remedial Group, and 0.70±0.1 6 mg/L for the NH Group) among the 3 groups. Urinary NGAL also did not differ significantly among the 3 groups at 6 h or at 48 h (6.31±6.60 ng/ml for the Preventive Group, 5.00±5.86 ng/ml for the Remedial Group, and 6.97±6.37 ng/ml for the NH Group) after the procedure. Subgroup analysis in patients who underwent percutaneous coronary intervention (PCI) showed that there was no significant difference in serum Cr, Cys C, or urinary NGAL at different time points among the 3 groups. CONCLUSIONS Saline hydration during the perioperative period might be unnecessary in patients with very low-risk profiles of CIN.