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1.
Nat Commun ; 14(1): 6924, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37903755

RESUMO

Studying language evolution brings a crucial perspective to bear on questions of human prehistory. As the most linguistically diverse region on earth, East and Southeast Asia have witnessed extensive sociocultural and ethnic contacts among different language communities. Especially, the Kra-Dai language family exhibits tremendous socio-cultural importance in these regions. Due to limited historical accounts, however, there are several controversies on their linguistic relatedness, ambiguities regarding the divergence time, and uncertainties on the dispersal patterns. To address these issues, here we apply Bayesian phylogenetic methods to analyze the largest lexical dataset containing 646 cognate sets compiled for 100 Kra-Dai languages. Our dated phylogenetic tree showed their initial divergence occurring approximately 4000 years BP. Phylogeographic results supported the early Kra-Dai language dispersal from the Guangxi-Guangdong area of South China towards Mainland Southeast Asia. Coupled with genetic, archaeological, paleoecologic, and paleoclimatic data, we demonstrated that the Kra-Dai language diversification could have coincided with their demic diffusion and agricultural spread shaped by the global climate change in the late Holocene. The interdisciplinary alignments shed light on reconstructing the prehistory of Kra-Dai languages and provide an indispensable piece of the puzzle for further studying prehistoric human activities in East and Southeast Asia.


Assuntos
Idioma , Humanos , Filogenia , China , Teorema de Bayes , Filogeografia
2.
Metallomics ; 15(9)2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37591604

RESUMO

Synchrotron-based micro-X-ray fluorescence analysis (µXRF) is a nondestructive and highly sensitive technique. However, element mapping of rare earth elements (REEs) under standard conditions requires care, since energy-dispersive detectors are not able to differentiate accurately between REEs L-shell X-ray emission lines overlapping with K-shell X-ray emission lines of common transition elements of high concentrations. We aim to test REE element mapping with high-energy interference-free excitation of the REE K-lines on hyperaccumulator plant tissues and compare with measurements with REE L-shell excitation at the microprobe experiment of beamline P06 (PETRA III, DESY). A combination of compound refractive lens optics (CRLs) was used to obtain a micrometer-sized focused incident beam with an energy of 44 keV and an extra-thick silicon drift detector optimized for high-energy X-ray detection to detect the K-lines of yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), and neodymium (Nd) without any interferences due to line overlaps. High-energy excitation from La to Nd in the hyperaccumulator organs was successful but compared to L-line excitation less efficient and therefore slow (∼10-fold slower than similar maps at lower incident energy) due to lower flux and detection efficiency. However, REE K-lines do not suffer significantly from self-absorption, which makes XRF tomography of millimeter-sized frozen-hydrated plant samples possible. The K-line excitation of REEs at the P06 CRL setup has scope for application in samples that are particularly prone to REE interfering elements, such as soil samples with high concomitant Ti, Cr, Fe, Mn, and Ni concentrations.


Assuntos
Cério , Síncrotrons , Raios X , Lantânio , Microscopia de Fluorescência
3.
Environ Sci Technol ; 57(17): 6922-6933, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37071813

RESUMO

Rare earth elements (REEs) are critical for numerous modern technologies, and demand is increasing globally; however, production steps are resource-intensive and environmentally damaging. Some plant species are able to hyperaccumulate REEs, and understanding the biology behind this phenomenon could play a pivotal role in developing more environmentally friendly REE recovery technologies. Here, we identified a REE transporter NRAMP REE Transporter 1 (NREET1) from the REE hyperaccumulator fern Dicranopteris linearis. Although NREET1 belongs to the natural resistance-associated macrophage protein (NRAMP) family, it shares a low similarity with other NRAMP members. When expressed in yeast, NREET1 exhibited REE transport capacity, but it could not transport divalent metals, such as zinc, nickel, manganese, or iron. NREET1 is mainly expressed in D. linearis roots and predominantly localized in the plasma membrane. Expression studies in Arabidopsis thaliana revealed that NREET1 functions as a transporter mediating REE uptake and transfer from root cell walls into the cytoplasm. Moreover, NREET1 has a higher affinity for transporting light REEs compared to heavy REEs, which is consistent to the preferential enrichment of light REEs in field-grown D. linearis. We therefore conclude that NREET1 may play an important role in the uptake and consequently hyperaccumulation of REEs in D. linearis. These findings lay the foundation for the use of synthetic biology techniques to design and produce sustainable, plant-based REE recovery systems.


Assuntos
Gleiquênias , Proteínas de Membrana Transportadoras , Metais Terras Raras , Membrana Celular , Gleiquênias/metabolismo , Zinco/metabolismo
4.
J Hazard Mater ; 452: 131254, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36965356

RESUMO

Dicranopteris linearis is the best-known hyperaccumulator species of rare earth elements (REEs) and silicon (Si), capable of dealing with toxic level of REEs. Hence, this study aimed to clarify how D. linearis leaves cope with excessive REE stress, and whether Si plays a role in REE detoxification. The results show that lanthanum (La - as a representative of the REEs) stress led to decreased biomass and an increase of metabolism related to leaf cell wall synthesis and modification. However, the La stress-induced responses, especially the increase of pectin-related gene expression level, pectin polysaccharides concentration, and methylesterase activity, could be mitigated by Si supply. Approximately 70% of the Si in D. linearis leaves interacted with the cell walls to form organosilicon Si-O-C linkages. The Si-modified cell walls contained more hydroxyl groups, leading to a more efficient REE retention compared to the Si-free ones. Moreover, this [Si-cell wall] matrix increased the pectin-La accumulation capacity by 64%, with no effect on hemicellulose-La and cellulose-La accumulation capacity. These results suggest that [Si-pectin] matrix fixation is key in REE detoxification in D. linearis, laying the foundation for the development of phytotechnological applications (e.g., REE phytomining) using this species in REE-contaminated sites.


Assuntos
Metais Terras Raras , Traqueófitas , Silício , Pectinas , Lantânio
5.
Plant J ; 113(4): 677-697, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36534087

RESUMO

Salt stress is one of the major causes of reduced crop production, limiting agricultural development globally. Plants have evolved with complex systems to maintain the balance between growth and stress responses, where signaling pathways such as hormone signaling play key roles. Recent studies revealed that hormones are modulated by microRNAs (miRNAs). Previously, two sweet sorghum (Sorghum bicolor) inbred lines with different salt tolerance were identified: the salt-tolerant M-81E and the salt-sensitive Roma. The levels of endogenous hormones in M-81E and Roma varied differently under salt stress, showing a different balance between growth and stress responses. miRNA and degradome sequencing showed that the expression of many upstream transcription factors regulating signal transduction and hormone-responsive genes was directly induced by differentially expressed miRNAs, whose levels were very different between the two sweet sorghum lines. Furthermore, the effects of representative miRNAs on salt tolerance in sorghum were verified through a transformation system mediated by Agrobacterium rhizogenes. Also, miR-6225-5p reduced the level of Ca2+ in the miR-6225-5p-overexpressing line by inhibiting the expression of the Ca2+ uptake gene SbGLR3.1 in the root epidermis and affected salt tolerance in sorghum. This study provides evidence for miRNA-mediated growth and stress responses in sweet sorghum.


Assuntos
MicroRNAs , Sorghum , MicroRNAs/genética , MicroRNAs/metabolismo , Sorghum/metabolismo , Estresse Fisiológico/genética , Estresse Salino/genética , Grão Comestível/genética , Hormônios/metabolismo , Regulação da Expressão Gênica de Plantas/genética
6.
Sci Total Environ ; 809: 152075, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-34890651

RESUMO

The exploitation of ion-adsorption rare earth element (REE) deposits in South China has left large areas of mine tailings. However, limited remediation practices on these tailings have been reported, and how the remediation strategies and economic plants cultivation affect the biogeochemical cycles of nutrients, REEs and Al remains unclear. The aim of the present study was to investigate the effects of the combination of the addition of soil amendment and the root development and activity of a fiber plant ramie (Boehmeria nivea L.) on the availability and distribution of nutrients, as well as of REEs and other potentially toxic elements (e.g. Al) in the soil-plant system. The results showed that the application of organic amendment and ramie planting induced a significant increase in soil pH, total carbon (C), nitrogen (N), and other nutrient (e.g. P and Ca) concentrations, while led to a decrease of 80-90% and 60-90% in soil extractable REE and Al concentrations respectively. Matrices of correlation showed that soil pH, total C, N, and P concentrations were among the most important factors controlling the availability of soil REEs and Al, and root characteristics (e.g. fine root length). The total C, N, P and extractable nutrient concentrations, and electrical conductivity were higher in the rhizosphere soils of ramie than those in the bulk soils. Moreover, more than 60% of the quantity of REE and Al in the whole ramie plant was stored within the thick roots. These results showed that, in addition to amendment, the effects induced by the roots of ramie could further improve soil properties through C input, nutrient mobilization and toxic element stabilization. Our study concludes that ramie planting with organic amendment is a promising phytostabilization strategy for the remediation of REE mine tailings in South China.


Assuntos
Boehmeria , Poluentes do Solo , Adsorção , Nutrientes , Solo , Poluentes do Solo/análise
7.
Sci Total Environ ; 805: 150335, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34818777

RESUMO

Organic acids play an important role in metal tolerance, uptake, and translocation in hyperaccumulators. Phytolacca americana is a rare earth element (REE) hyperaccumulator, but the underlying mechanisms on REE tolerance and accumulation mediated by organic acids are poorly understood. Here, we reported for the first time the strategy of P. americana to enhance REE tolerance and accumulation through organic acids from root external secretion to internal biosynthesis. Different from the exclusion of heavy metal by organic acid in the typical plants, the results showed that oxalate secretion (0.3-0.6 µmol h-1 g-1 root DW) induced by yttrium (Y) could not prevent Y from entering the roots, resulting in excess Y uptake by P. americana. Yttrium stress also stimulated the accumulation of malate and citrate by 1.4- and 2.0-folds in the root cortex. Exogenous malate and citrate promoted the redistribution of Y from the root cell walls to the shoot by 30% and 21%, respectively. Based on comparative transcriptome analysis, 6-fold up-regulation was observed in PaNIP1;2, whose homology AtNIP1;2 is responsible for the transport of Al-malate in Arabidopsis. These results suggested that the promoted formation of Y-malate complexes within the roots potentially accelerated the transport of Y from P. americana roots to shoots through PaNIP1;2. Our study revealed the potential mechanism of organic acids in the external exclusion and internal detoxification and translocation of REE in P. americana roots, which provided a basis for improving the efficiency of REE phytoextraction.


Assuntos
Arabidopsis , Metais Terras Raras , Phytolacca americana , Compostos Orgânicos , Raízes de Plantas
8.
Front Genet ; 12: 740167, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630530

RESUMO

The population prehistory of Xinjiang has been a hot topic among geneticists, linguists, and archaeologists. Current ancient DNA studies in Xinjiang exclusively suggest an admixture model for the populations in Xinjiang since the early Bronze Age. However, almost all of these studies focused on the northern and eastern parts of Xinjiang; the prehistoric demographic processes that occurred in western Xinjiang have been seldomly reported. By analyzing complete mitochondrial sequences from the Xiabandi (XBD) cemetery (3,500-3,300 BP), the up-to-date earliest cemetery excavated in western Xinjiang, we show that all the XBD mitochondrial sequences fall within two different West Eurasian mitochondrial DNA (mtDNA) pools, indicating that the migrants into western Xinjiang from west Eurasians were a consequence of the early expansion of the middle and late Bronze Age steppe pastoralists (Steppe_MLBA), admixed with the indigenous populations from Central Asia. Our study provides genetic links for an early existence of the Indo-Iranian language in southwestern Xinjiang and suggests that the existence of Andronovo culture in western Xinjiang involved not only the dispersal of ideas but also population movement.

9.
Chemosphere ; 282: 131096, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34470158

RESUMO

The plant Phytolacca americana L. simultaneously hyperaccumulates manganese (Mn) and rare earth elements (REEs), but the underlying mechanisms are largely unknown. In this study, P. americana and the corresponding rhizosphere soil samples were collected from an ion-adsorption REE mine area in China, and the elemental composition and soil properties were analyzed in order to explore the relationship between metal accumulation and soil properties. The results show that P. americana accumulates high concentrations of REEs (up to 1040 mg kg-1), Mn (up to 10400 mg kg-1) and aluminum (Al) (up to 5960 mg kg-1) in leaves. The REE concentrations in leaves were positively correlated with those of Al, Fe and Zn, while light REE concentrations were negatively correlated with P concentrations (p < 0.05). The soil properties explained 81.7%, 72.9% and 67.1% of REEs, Mn and Al accumulated in P. americana, respectively. The variation of REE accumulation in P. americana was primarily explained by plant available P (24.4%), pH (12.9%), TOC (9.4%) and total P (7.7%). The accumulation of Mn was primarily explained by plant available REEs (42.9%) and available Al (13.1%) while Al in P. americana was primarily explained by soil pH (14.4%). This study suggests the potential by regulation of soil properties in improving the efficiency of phytoextraction for REEs by hyperaccumulators.


Assuntos
Metais Terras Raras , Phytolacca americana , Poluentes do Solo , Alumínio , Biodegradação Ambiental , Manganês , Raízes de Plantas , Solo
10.
Int J Surg Case Rep ; 84: 106076, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34157547

RESUMO

BACKGROUND: Iatrogenic pseudoaneurysms in scalp vessels are an uncommon complication after cranial surgery. This paper reports a case of scalp pseudoaneurysm in the superficial temporal artery (STA) after forceful hook retraction in craniectomy and reviews the relevant literature. CASE DESCRIPTION: A 36-year-old man with history of hypertension and depression presented to the emergency department with head injury after using sedation medication. Brain computed tomography (CT) revealed a 2-cm-thick right parietal extradural hematoma (EDH) with parietal skull fracture, a bilateral lower frontotemporal contusional intracerebral hematoma, diffuse subarachnoid hemorrhage, and a right frontotemporoparietal subdural hematoma. To prevent EDH progression, frontotemporal emergency craniectomy to remove the EDH was performed. The next day, a firm, painful mass measuring 3 × 3.5 cm2 was discovered over the right frontal scalp. The mass was close to the site where the scalp hook retractor had been placed during surgery. Sonography revealed pulsatile blood flow with an arterial feeder inside the mass. CT angiography revealed a 1 × 1.2 × 0.7 cm3 pseudoaneurysm in the right frontal scalp from the frontal branch of the STA. We scheduled a resection of the pseudoaneurysm and combined cranioplasty on the 29th postoperative day. The pseudoaneurysm was resected en bloc. The patient was discharged with clear consciousness and intact muscle power. CONCLUSION: The complications of STA pseudoaneurysms caused by scalp hook retractors are rare and not yet well reported. Surgeons must avoid injuring the STA when using a scalp hook retractor.

11.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33558418

RESUMO

The expansion of anatomically modern humans (AMHs) from Africa around 65,000 to 45,000 y ago (ca. 65 to 45 ka) led to the establishment of present-day non-African populations. Some paleoanthropologists have argued that fossil discoveries from Huanglong, Zhiren, Luna, and Fuyan caves in southern China indicate one or more prior dispersals, perhaps as early as ca. 120 ka. We investigated the age of the human remains from three of these localities and two additional early AMH sites (Yangjiapo and Sanyou caves, Hubei) by combining ancient DNA (aDNA) analysis with a multimethod geological dating strategy. Although U-Th dating of capping flowstones suggested they lie within the range ca. 168 to 70 ka, analyses of aDNA and direct AMS 14C dating on human teeth from Fuyan and Yangjiapo caves showed they derive from the Holocene. OSL dating of sediments and AMS 14C analysis of mammal teeth and charcoal also demonstrated major discrepancies from the flowstone ages; the difference between them being an order of magnitude or more at most of these localities. Our work highlights the surprisingly complex depositional history recorded at these subtropical caves which involved one or more episodes of erosion and redeposition or intrusion as recently as the late Holocene. In light of our findings, the first appearance datum for AMHs in southern China should probably lie within the timeframe set by molecular data of ca. 50 to 45 ka.


Assuntos
Arqueologia , Cavernas/química , DNA Antigo/análise , Fósseis , Sedimentos Geológicos/análise , Migração Humana/história , Datação Radiométrica/métodos , China , História Antiga , Humanos
12.
Front Microbiol ; 12: 751794, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35087482

RESUMO

Much effort has been made to remediate the degraded mine lands that bring severe impacts to the natural environments. However, it remains unclear what drives the recovery of biodiversity and ecosystem functions, making the restoration of these fragile ecosystems a big challenge. The interactions among plant species, soil communities, and abiotic conditions, i.e., plant-soil feedbacks (PSFs), significantly influence vegetation development, plant community structure, and ultimately regulate the recovery of ecosystem multi-functionality. Here, we present a conceptual framework concerning PSFs patterns and potential mechanisms in degraded mine lands. Different from healthy ecosystems, mine lands are generally featured with harsh physical and chemical properties, which may have different PSFs and should be considered during the restoration. Usually, pioneer plants colonized in the mine lands can adapt to the stressful environment by forming tolerant functional traits and gathering specific soil microbial communities. Understanding the mechanisms of PSFs would enhance our ability to predict and alter both the composition of above- and below-ground communities, and improve the recovery of ecosystem functions in degraded mine lands. Finally, we put forward some challenges of the current PSFs study and discuss avenues for further research in the ecological restoration of degraded mine lands.

13.
aBIOTECH ; 2(1): 64-78, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36304478

RESUMO

The molecular mechanism of the maintenance and differentiation of plant stem cells is an eternal theme in studies on plant growth and development. Recent advances in single-cell RNA sequencing (scRNA-seq) methods have completely changed the understanding of cell heterogeneity and cell function, allowing research precision to identify the differentiation trajectory of stem cells maintained and differentiated at the cellular level. This review aimed to mainly discuss the novel insights provided by scRNA-seq for the maintenance and initiation of plant stem cells, cell differentiation, cell response to environmental changes, and improvement strategies for scRNA-seq. In addition, it highlighted additional perspectives beyond scRNA-seq, such as spatial transcriptomes, epigenomes, and single-cell multiomics, for a renewed understanding of stem cell maintenance and cell differentiation, thus providing potential targets and theoretical foundations for crop improvement.

14.
Plant Cell Rep ; 40(2): 271-282, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33025178

RESUMO

KEY MESSAGE: Cytokinins are a class of phytohormone that participate in the regulation of the plant growth, development, and stress response. In this review, the potential regulating mechanism during plant growth and stress response are discussed. Cytokinins are a class of phytohormone that participate in the regulation of plant growth, physiological activities, and yield. Cytokinins also play a key role in response to abiotic stresses, such as drought, salt and high or low temperature. Through the signal transduction pathway, cytokinins interact with various transcription factors via a series of phosphorylation cascades to regulate cytokinin-target gene expression. In this review, we systematically summarize the biosynthesis and metabolism of cytokinins, cytokinin signaling, and associated gene regulation, and highlight the function of cytokinins during plant development and resistance to abiotic stress. We also focus on the importance of crosstalk between cytokinins and other classes of phytohormones, including auxin, ethylene, strigolactone, and gibberellin. Our aim is to provide a comprehensive overview of recent findings on the mechanisms by which cytokinins act as central regulators of plant development and stress reactions, and highlight topics for future research.


Assuntos
Citocininas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Plantas/genética , Transdução de Sinais , Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Desenvolvimento Vegetal , Fenômenos Fisiológicos Vegetais , Estresse Fisiológico
15.
Cell Mol Gastroenterol Hepatol ; 11(4): 1211-1226.e15, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33279689

RESUMO

BACKGROUND AND AIMS: Gallstone disease (cholelithiasis) is a cholesterol-related metabolic disorders with strong familial predisposition. Mitochondrial DNA (mtDNA) variants accumulated during human evolution are associated with some metabolic disorders related to modified mitochondrial function. The mechanistic links between mtDNA variants and gallstone formation need further exploration. METHODS: In this study, we explored the possible associations of mtDNA variants with gallstone disease by comparing 104 probands and 300 controls in a Chinese population. We constructed corresponding cybrids using trans-mitochondrial technology to investigate the underlying mechanisms of these associations. Mitochondrial respiratory chain complex activity and function and cholesterol metabolism were assessed in the trans-mitochondrial cell models. RESULTS: Here, we found a significant association of mtDNA 827A>G with an increased risk of familial gallstone disease in a Chinese population (odds ratio [OR]: 4.5, 95% confidence interval [CI]: 2.1-9.4, P=1.2×10-4). Compared with 827A cybrids (haplogroups B4a and B4c), 827G cybrids (haplogroups B4b and B4d) had impaired mitochondrial respiratory chain complex activity and function and activated JNK and AMPK signaling pathways. Additionally, the 827G cybrids showed disturbances in cholesterol transport and accelerated development of gallstones. Specifically, cholesterol transport through the transporter ABCG5/8 was increased via activation of the AMPK signaling pathway in 827G cybrids. CONCLUSIONS: Our findings reveal that mtDNA 827A>G induces aberrant mitochondrial function and abnormal cholesterol transport, resulting in increased occurrence of gallstones. The results provide an important biological basis for the clinical diagnosis and prevention of gallstone disease in the future.


Assuntos
Povo Asiático/genética , DNA Mitocondrial/genética , Cálculos Biliares/patologia , Predisposição Genética para Doença , Mitocôndrias/patologia , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , China/epidemiologia , Colesterol/metabolismo , DNA Mitocondrial/análise , Feminino , Cálculos Biliares/epidemiologia , Cálculos Biliares/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/genética , Fatores de Risco , Adulto Jovem
16.
Biotechnol Adv ; 45: 107656, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33181242

RESUMO

Over 160 RNA modifications have been identified, including N7-methylguanine (m7G), N6-methyladenosine (m6A), and 5-methylcytosine (m5C). These modifications play key roles in regulating the fate of RNA. In eukaryotes, m6A is the most abundant mRNA modification, accounting for over 80% of all RNA methylation modifications. Highly dynamic m6A modification may exert important effects on organismal reproduction and development. Significant advances in understanding the mechanism of m6A modification have been made using immunoprecipitation, chemical labeling, and site-directed mutagenesis, combined with next-generation sequencing. Single-molecule real-time and nanopore direct RNA sequencing (DRS) approaches provide additional ways to study RNA modifications at the cellular level. In this review, we explore the technical history of identifying m6A RNA modifications, emphasizing technological advances in detecting m6A modification. In particular, we discuss the challenge of generating accurate dynamic single-base resolution m6A maps and also strategies for improving detection specificity. Finally, we outline a roadmap for future research in this area, focusing on the application of RNA epigenetic modification, represented by m6A modification.


Assuntos
Epigênese Genética , Sequenciamento de Nucleotídeos em Larga Escala , Adenosina/análogos & derivados , Metilação , RNA Mensageiro/metabolismo
17.
Hum Biol ; 91(4): 257-277, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32767896

RESUMO

The Fujian Tanka people are officially classified as a southern Han ethnic group, whereas they have customs similar to Daic and Austronesion people. Whether they originated in Han or Daic people, there is no consensus. Three hypotheses have been proposed to explain the origin of this group: (1) the Han Chinese origin, (2) the ancient Daic origin, (3) and the admixture between Daic and Han. This study addressed this issue by analyzing the paternal Y chromosome and maternal mtDNA variation of 62 Fujian Tanka and 25 neighboring Han in Fujian. The southern East Asian predominant haplogroups (e.g., Y-chromosome O1a1a-P203 and O1b1a1a-M95, and mtDNA F2a, M7c1, and F1a1) had relatively high frequencies in Tanka. The interpopulation comparison revealed that the Tanka have a closer affinity with Daic populations than with Han Chinese in paternal lineages but are closely clustered with southern Han populations such as Hakka and Chaoshanese in maternal lineages. Network and haplotype-sharing analyses also support the admixture hypothesis. The Fujian Tanka mainly originate from the ancient indigenous Daic people and have only limited gene flows from Han Chinese populations. Notably, the divergence time inferred by the Tanka-specific haplotypes indicates that the formation of Fujian Tanka was a least 1033.8-1050.6 years before present (the early Northern Song dynasty), indicating that they are an indigenous population, not late Daic migrants from southwestern China.


Assuntos
Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Genética Populacional/métodos , Povo Asiático/genética , China/etnologia , DNA Mitocondrial/história , Etnicidade/genética , Feminino , Testes Genéticos/métodos , Haplótipos/genética , História Antiga , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética
18.
Trends Plant Sci ; 25(9): 859-867, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32376086

RESUMO

N6-methyladenosine (m6A) is the most common type of eukaryotic mRNA modification. It plays an important role in regulating plant growth and development and stress resistance. m6A modification influences nearly all aspects of RNA metabolism and functionality and has great potential for improving crop quality. However, changing m6A modification levels as a whole may have unpredictable effects, making it impossible to accurately predict the effect of specific m6A modifications on RNA. In this opinion article, the main challenges and possible solutions for exploring m6A modification functions in plant systems are discussed. An m6A editing platform that uses new high-throughput methods to identify m6A modification at single-base resolution, and genome editing for selective editing of specific m6A sites for crop improvement is proposed.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Desenvolvimento Vegetal , Plantas/genética , RNA
19.
Neurochem Res ; 45(7): 1536-1550, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32222876

RESUMO

Injury severity is correlated with poor prognosis after traumatic brain injury (TBI). It is not known whether triglycerides (TGs) or total cholesterol (TC) is good biomarker of increased injury of neuroinflammation and apoptosis in a high fat diet (HFD)-treated rat after TBI episodes. Five-week-old male Sprague-Dawley (SD) rats were fed a HFD for 8 weeks. The anesthetized male SD rats were divided into three sub-groups: sham-operated and TBI with 1.6 atm or with 2.4 atm fluid percussion injury (FPI). Cell infarction volume (triphenyltetrazolium chloride stain), tumor necrosis factor-alpha (TNF-α) expression in the microglia (OX42 marker) and astrocytes (Glial fibrillary acidic protein marker), TNF-α receptor expression in the neurons (TNFR1 and TNFR2 markers), and the extent of neuronal apoptosis (TUNEL marker) were evaluated by immunofluorescence, and the functional outcome was assessed by an inclined plane test. These tests were performed 72 h after TBI. Serum triglyceride and cholesterol levels were measured at 24, 48 and 72 h after TBI. The FPI with 2.4 atm significantly increased body weight loss, infarction volume, neuronal apoptosis and TNF-α expression in the microglia and astrocytes, and it decreased the maximum grasp degree and TNFR1 and TNFR2 expression in neurons at the 3rd day following TBI. The serum TG level was positively correlated with FPI force, infarction volume, Neu-N-TUNEL, GFAP-TNFα, and OX42-TNFα Simultaneously; the serum TG level was negatively correlated with Neu-N-TNFR1 and Neu-N-TNFR2. TG is a good biomarker of increased injury for neuroinflammation and apoptosis at the 3rd day after TBI in HFD rats.


Assuntos
Lesões Encefálicas Traumáticas/sangue , Lesões Encefálicas Traumáticas/patologia , Dieta Hiperlipídica/efeitos adversos , Índice de Gravidade de Doença , Triglicerídeos/sangue , Animais , Biomarcadores/sangue , Lesões Encefálicas Traumáticas/etiologia , Masculino , Ratos , Ratos Sprague-Dawley
20.
World Neurosurg ; 137: 214-217, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32058108

RESUMO

BACKGROUND: Pregnancy is a known risk factor for spontaneous spinal epidural hematoma. During cesarean section or vaginal delivery, the unstable hemodynamic status that may occur owing to fluctuation of intra-abdominal pressure increases the possibility of spontaneous spinal epidural hematoma. During labor and the postpartum period, neurologic symptoms may be masked by labor pain or anesthesia block, which makes early diagnosis difficult, especially in the obstetric clinic without a neurologist or neurosurgeon. CASE DESCRIPTION: A 28-year-old woman who had a normal spontaneous delivery under epidural anesthesia developed bilateral lower limb flaccid paralysis and loss of sensation 12.5 hours after delivery. Magnetic resonance imaging showed a 5.2 × 0.9 × 2 cm spinal epidural hematoma with severe spinal cord stenosis at the T2-T5 level with no evidence of a vascular anomaly. After emergent evacuation of the spinal epidural hematoma, lower limb muscle power improved from 0/5 to 1/5, and sensation gradually returned to bilateral lower limbs 22 days postoperatively. Deep vein thrombosis developed at 35 days postoperatively, and an inferior vena cava filter was implanted with urokinase infusion for thrombolytic therapy. She was discharged on day 52 after admission, and lower limb muscle power returned to normal after 3 months. CONCLUSIONS: Clinicians should observe postpartum women for signs of myelopathy or back tenderness and closely monitor neurologic function until anesthesia has run its course. A prompt diagnosis can enable prompt intervention.


Assuntos
Descompressão Cirúrgica , Parto Obstétrico , Hematoma Epidural Espinal/cirurgia , Laminectomia , Transtornos Puerperais/cirurgia , Compressão da Medula Espinal/cirurgia , Adulto , Analgesia Epidural , Anestesia Epidural , Inibidores do Fator Xa/uso terapêutico , Feminino , Fibrinolíticos/uso terapêutico , Hematoma Epidural Espinal/complicações , Hematoma Epidural Espinal/diagnóstico por imagem , Humanos , Hipestesia/etiologia , Extremidade Inferior , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Paraplegia , Complicações Pós-Operatórias/terapia , Gravidez , Transtornos Puerperais/diagnóstico por imagem , Recuperação de Função Fisiológica , Rivaroxabana/uso terapêutico , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/etiologia , Terapia Trombolítica , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Filtros de Veia Cava , Trombose Venosa/terapia
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