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1.
J Diabetes Investig ; 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33460512

RESUMO

AIMS/INTRODUCTION: Diabetic cardiovascular autonomic neuropathy (DCAN) seriously threatens the prognosis and quality of life of patients with type 2 diabetes mellitus, associated with increased mortality. The present study aimed to investigate the relevant risk factors of DCAN. MATERIALS AND METHODS: The present study enrolled a total of 109 patients with type 2 diabetes mellitus. DCAN was defined as a score of at least 2 points in Ewing tests. The updated homeostasis model assessment of insulin resistance (HOMA2-IR) based on fasting C-peptide was calculated to reflect insulin resistance. Logistic regression analysis, interaction and stratified analyses were used to investigate the relationship between HOMA2-IR or other indicators and DCAN. Receiver operating characteristic analysis was carried out to estimate the discriminative value of the variables independently associated with DCAN and to determine the optimal cut-off point of these models to screen DCAN. RESULTS: The HOMA2-IR levels were significantly higher in patients with DCAN, and tended to be worsened with the progression of the DCAN. Logistic regression analysis showed an independent association between HOMA2-IR (odds ratio 39.30, 95% confidence interval 7.17-215.47) and DCAN. HOMA2-IR (area under the curve 0.878, 95% confidence interval 0.810-0.946; cut-off value 1.735) individually predicted DCAN significantly higher than the other independent risk factors individually used, whereas models combining HOMA2-IR and other risk factors did not significantly boost the diagnostic power. CONCLUSIONS: Insulin resistance is independently associated with DCAN. HOMA2-IR presents to be a highly accurate and parsimonious indicator for DCAN screening. Patients with HOMA2-IR >1.735 are at a high risk of DCAN; thus, priority diagnostic tests should be carried out for these patients for timely integrated intervention.

2.
Environ Sci Technol ; 55(4): 2276-2284, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33497189

RESUMO

Arsenic (As) contamination in soils is of great concerns due to its toxicity to plants. As an analogue, phosphorus plays an important role in protecting plants from As toxicity. In this study, we identified a new phosphate transporter 2 (PHT2), PvPht2;1, from As-hyperaccumulator Pteris vittata and analyzed its functions in As and P transport in a yeast mutant, and model plant Arabidopsis thalian. PvPht2;1 contained 12 transmembrane domains, sharing high identity with PHT2 genes in diverse plants. Further, independent of external P or As levels, PvPht2;1 was mainly expressed in P. vittata fronds with the expression being 3-4 folds higher than that in the roots and rhizomes. Localized to the chloroplasts based on GFP-fused PvPht2;1 in model plant tobacco, PvPht2;1 functioned as a low-affinity P transporter. Under As exposure, PvPht2;1 yeast transformants showed comparable growth with the control while high-affinity P transporter PvPht1;3 transformants showed better growth, suggesting that PvPht2;1 transported P but slower than PvPht1;3 transporter. Expressing PvPht2;1 in A. thaliana increased its shoot P concentration without influencing its As accumulation. Further, the chloroplasts' P content in transgenic A. thaliana increased by 37-59% than wild-type (WT) plants. Under As exposure, the photosynthesis of PvPht2;1-expressing A. thaliana remained stable but that of WT plants decreased. The data indicate that, under As stress, expressing PvPht2;1 in A. thaliana enhanced its P transport to the chloroplasts and protected its photosynthesis. In short, highly expressed in the fronds and not impacted by As exposure, chloroplast-located PvPht2;1 may have protected As-hyperaccumulator P. vittata from As toxicity by efficiently transporting only P to its chloroplasts.

3.
Chemosphere ; : 128979, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33218728

RESUMO

Microplastics and heavy metals are discharged into a freshwater environment either directly or via surface runoff and are largely deposited in sediments, posing risks to aquatic organisms. Few studies have thus far been devoted to the interaction of microplastics and heavy metals in sediments. Whether microplastics can affect the toxicity and accumulation of heavy metals in submerged macrophytes remains unclear. We evaluated the effects of polyvinyl chloride microplastics (PVC-MPs) and cadmium (Cd) exposure levels (0, 5, 15, and 25 mg) on Vallisneria natans (Lour.) Hara grown in sediment in a microcosm experiment for 14 d. In this study, PVC-MPs decreased the fresh weights of V. natans in the absence of Cd and markedly reduced the fresh weights at 5 and 15 mg Cd exposure levels. Moreover, PVC-MPs substantially increased the malondialdehyde (MDA) content of V. natans leaves at a Cd exposure of 25 mg. However, the PVC-MPs neither reduced the Cd concentration nor independently increased the antioxidant enzyme activities of the plants. These findings indicate that microplastics can independently, or jointly with a Cd contaminant, inhibit the growth of submerged macrophytes rather than reduce Cd toxicity. To our knowledge, this study is the first to evaluate the effects of microplastics and Cd exposure in sediments on the growth and physiological traits of submerged macrophytes, which could provide important implications for the interaction and future risk assessment of microplastics and heavy metals in sediments of freshwater ecosystems.

4.
Org Biomol Chem ; 18(43): 8916-8920, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33118589

RESUMO

Chromanone is a privileged structure with a wide range of unique biological activities. A phosphine-promoted, three-component domino sequence of salicylaldehyde with but-3-yn-2-one was well designed for the construction of the chromanone skeleton under mild conditions. As a consequence, a series of novel chromanone analogues bearing an all-carbon quaternary center were facilely assembled from commercially available starting materials with moderate to good yields, which hold promising applications in pharmacological studies. Mechanistic experiments were conducted to confirm the proposed mechanism.

6.
J Hazard Mater ; 399: 122895, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32937698

RESUMO

Arsenic-hyperaccumulator Pteris vittata is efficient in As absorption, reduction, and translocation. But the molecular mechanisms and locations of arsenate (AsV) reduction in P. vittata are still unclear. Here, we identified two new arsenate reductase genes from P. vittata, PvHAC1 and PvHAC2. Two PvHAC genes encoded a rhodanase-like protein, which were localized in the cytoplasm and nucleus. Both recombinant Escherichia coli strains and transgenic Arabidopsis thaliana lines showed arsenate reductase ability after expressing PvHAC genes. Further, expressing PvHAC2 enhanced As tolerance and reduced As accumulation in A. thaliana shoots under AsV exposure. Based on expression pattern analysis, PvHAC1 and PvHAC2 were predominantly expressed in the rhizomes and fronds of P. vittata. Different from those of HAC homologous genes in non-hyperaccumulators, little PvHAC was expressed in the roots. Besides, PvHAC1 expression was strongly upregulated under AsV exposure but not AsIII. The data suggest that arsenate reductase PvHAC1 in the rhizomes coupled with arsenate reductase PvHAC2 in the fronds of P. vittata played a critical role in As-hyperaccumulation by P. vittata, which helps to further improve its utility in phytoremediation of As-contaminated soils.

7.
Adipocyte ; 9(1): 384-400, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32684073

RESUMO

We explored potential biomarkers and molecular mechanisms regarding multiple benefits after bariatric surgery. Differentially expressed genes (DEGs) for subcutaneous adipose tissue (AT) after bariatric surgery were identified by analyzing two expression profiles from the GEO. Subsequently, enrichment analysis, GSEA, PPI network, and gene-microRNAs and gene-TFs networks were interrogated to identify hub genes and associated pathways. Co-expressed DEGs included one that was up-regulated and 22 that were down-regulated genes. The enrichment analyses indicated that down-regulated DEGs were significantly involved in inflammatory responses. GSEA provided comprehensive evidence that most genes enriched in pro-inflammation pathways, while gene-sets after surgery enriched in metabolism. We identified nine hub genes in the PPI network, most of which were validated as highly expressed and hypomethylated in obesity by Attie Lab Diabetes and DiseaseMeth databases, respectively. DGIdb was also applied to predict potential therapeutic agents that might reverse abnormally high hub gene expression. Bariatric surgery induces a significant shift from an obese pro-inflammatory state to an anti-inflammatory state, with improvement in adipocyte metabolic function - representing key mechanisms whereby AT function improves after bariatric surgery. Our study deepens a mechanistic understanding of the benefits of bariatric surgery and provides potential biomarkers or treatment targets for further research.

8.
Chemosphere ; 247: 125916, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32069716

RESUMO

Arsenic (As) and cadmium (Cd) are ubiquitous in the environment and they are both toxic to humans. When present in soils, they can enter food chain, thereby threatening human health. Water spinach (Ipomoea aquatica) is an important leafy vegetable, which is widely consumed in Asian countries. However, it is efficient in taking up As and Cd from soils and accumulating them in the edible parts. Therefore, it is of significance to reduce its As and Cd content, especially in contaminated soil. In this study, pot experiments were conducted to investigate the ability of As-hyperaccumulator Pteris vittata in reducing As and Cd uptake by water spinach under different phosphorus treatments. P. vittata was grown for 60 d in a contaminated-soil amended with P fertilizer (+P) or phosphate rock (+PR), followed by water spinach cultivation for another 30 d. Plant biomass, As and Cd contents in plants and soils, and soil pH were analyzed. We found that, P. vittata coupled with PR decreased the As concentration in water spinach shoots by 42%, probably due to As uptake by P. vittata. Moreover, P. vittata decreased the Cd accumulation in water spinach by 24-44%, probably due to pH increase of 0.47-0.61 after P. vittata cultivation. Taking together, the results showed that P. vittata coupled with PR decreased the As and Cd content in water spinach, which is of significance for improving food safety and protecting human health.


Assuntos
Arsênico/metabolismo , Biodegradação Ambiental , Cádmio/metabolismo , Ipomoea/metabolismo , Fosfatos/química , Pteris/química , Poluentes do Solo/metabolismo , Arsênico/análise , Biomassa , Cádmio/análise , Fertilizantes , Fósforo , Folhas de Planta/química , Solo/química , Poluentes do Solo/análise , Verduras , Água
9.
Sci Total Environ ; 715: 135298, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31859061

RESUMO

Arsenic (As) hyperaccumulator Pteris vittata is efficient in As uptake, translocation and accumulation, but the impacts of soil As concentrations on As accumulation and distribution in P. vittata are still unclear. The impacts of soil As (7.3, 63 and 228 mg kg-1) on plant growth and As accumulation in P. vittata after 6 months of growth were evaluated. Arsenic concentrations in the roots, midribs and pinna margin of P. vittata fronds of different maturity were determined by inductively coupled plasma mass spectrometry (ICP-MS) and scanning electron microscopy coupled with an energy dispersive spectrometer (SEM-EDS). While moderate As level at As63 didn't impact P. vittata growth, higher As at As228 decreased plant biomass by 38%. Under As stress, more As was accumulated in the senescing fronds (47%) and mature fronds (11%) than the young fronds. In senescing fronds, As concentrations in pinna margin were 2.3 times that of the midribs, consistent with As-induced necrotic symptom. Arsenic distribution based on SEM-EDS analysis revealed good correlation between Si and As in the pinnae (r = 0.49). Our data showed that As accumulation in pinna margin caused necrosis and Si may have a potential role in As detoxification in P. vittata.


Assuntos
Pteris , Arsênico , Biodegradação Ambiental , Raízes de Plantas , Solo , Poluentes do Solo
10.
Environ Sci Technol ; 54(2): 1045-1053, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31825207

RESUMO

Arsenic-hyperaccumulator Pteris vittata is efficient in As uptake, probably through phosphate transporters (Pht). Here, for the first time, we cloned a new PvPht1;4 gene from P. vittata and investigated its role in arsenate (AsV) uptake and transport in yeast and transgenic tobacco plants. On the basis of quantitative real-time polymerase chain reaction (qRT-PCR), PvPht1;4 was abundantly expressed in P. vittata fronds and roots, with its transcripts in the roots being induced by both P deficiency and As exposure. PvPht1;4 was localized to the plasma membrane, which complemented a yeast-mutant defective in P uptake and showed higher P transport affinity than PvPht1;3. Under AsV exposure, PvPht1;4 yeast transformants showed comparable tolerance as PvPht1;3, but higher As accumulation than PvPht1;2 transformants, indicating that PvPht1;4 had considerable AsV and P transport activity. However, in soil and hydroponic experiments, PvPht1;4 expressing tobacco lines accumulated 26-44 and 37-55% lower As in the shoots than wild type plants, with lower root-to-shoot As translocation. In the roots of PvPht1;4 lines, higher glutathione (GSH) contents and expression levels of GSH synthetase gene NtGSH2 were observed. In addition, the transcripts of AsIII-GSH transporter NtABCC1 in PvPht1;4 lines were upregulated. The data suggested that PvPht1;4 lines probably detoxified As by reducing AsV to AsIII, which was then complexed with GSH and stored in the root vacuoles, thereby reducing As translocation in transgenic tobacco. Given its strong AsV transport capacity, expression of PvPht1;4 provides a new molecular approach to reduce As accumulation in plant shoots.


Assuntos
Arsênico , Pteris , Poluentes do Solo , Biodegradação Ambiental , Proteínas de Transporte de Fosfato , Raízes de Plantas , Tabaco
11.
Environ Pollut ; 255(Pt 3): 113354, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31629223

RESUMO

Agricultural soil is one of the main sink for both heavy metals and nanomaterials (NMs). Whether NMs can impact heavy metals uptake or bioaccumulation in plants is unknown. Here, cucumber plants were cultivated in a multi-heavy metals contaminated soil amended with four types of NMs (SiO2, TiO2, ZnS and MoS2) separately for four weeks. Physiological and biochemical parameters were determined to investigate the impact of NMs on plant growth. Inductively coupled plasma mass spectrometry was employed to determine the metal content in plants. Results showed that none of the tested NMs impacted plants biomass, but all the NMs showed different degrees of reduction in heavy metals bioaccumulation in plant roots, stems and leaves. However, four NMs showed different degrees of reduction in macro and micro nutrients uptake. MoS2 decreased the bioaccumulation of heavy metals (As, Cd, Cr, Cu, Ni, Al, Ti and Pb) for 36.4-60.6% and nutrients (Mg, Fe, K, Si and Mn) for 40.1%-50.1% in roots. Exposure to MoS2 NMs also significantly increased 23.4% of Si in leaves, 205.6% and 83.9% of Mo in roots and stems, respectively. In general, the results of this study showed promising potential for NMs to reduce uptake of heavy metals in crop plants, especially MoS2 NMs. However, the negative impacts of perturbing nutrients uptake should be paid attention as well.


Assuntos
Cucumis sativus/química , Metais Pesados/análise , Nanoestruturas/análise , Poluentes do Solo/análise , Agricultura , Biomassa , Cucumis sativus/crescimento & desenvolvimento , Óxidos/análise , Desenvolvimento Vegetal , Raízes de Plantas/química , Dióxido de Silício/análise , Solo/química , Sulfetos/análise
12.
Sci Total Environ ; 690: 1178-1189, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31470481

RESUMO

Microbial arsenic transformation is important in As biogeochemical cycles in the environment. In this study, a new As-resistant bacterial strain Leclercia adecarboxylata As3-1 was isolated and its associated mechanisms in As resistance and detoxification were evaluated based on genome sequencing and gene annotations. After subjecting strain As3-1 to medium containing arsenate (AsV), AsV reduction occurred and an AsV-enhanced bacterial growth was observed. Strain As3-1 lacked arsenite (AsIII) oxidation ability and displayed lower AsIII resistance than AsV, probably due to its higher AsIII accumulation. Polymerase chain reaction and phylogenetic analysis showed that strain As3-1 harbored a typical AsV reductase gene (arsC) on the plasmids. Genome sequencing and gene annotations identified four operons phoUpstBACS, arsHRBC, arsCRDABC and ttrRSBCA, with 8 additional genes outside the operons that might have involved in As resistance and detoxification in strain As3-1. These included 5 arsC genes explaining why strain As3-1 tolerated high AsV concentrations. Besides ArsC, TtrB, TtrC and TtrA proteins could also be involved in AsV reduction and consequent energy acquisition for bacterial growth. Our data provided a new example of diverse As-regulating systems and AsV-enhanced growth without ArrA in bacteria. The information helps to understand the role of As in selecting microbial systems that can transform and utilize As.


Assuntos
Arsênico/metabolismo , Enterobacteriaceae/fisiologia , Poluentes Ambientais/metabolismo , Adaptação Fisiológica , Proteínas de Bactérias/genética , Enterobacteriaceae/genética , Genômica
13.
Environ Sci Technol ; 53(17): 10062-10069, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31369709

RESUMO

Rice (Oryza sativa) is a major food crop in the world, feeding half of the world's population. However, rice is efficient in taking up toxic metalloid arsenic (As), adversely impacting human health. Among different As species, inorganic As is more toxic than organic As. Thus, it is important to decrease inorganic As in rice to reduce human exposure from the food chain. The arsenite (AsIII) antiporter gene PvACR3;1 from As-hyperaccumulator Pteris vittata decreases shoot As accumulation when heterologously expressed in plants. In this study, three homozygous transgenic lines (L2, L4, and L7) of T3 generation were obtained after transforming PvACR3;1 into rice. At 5 µM of AsIII, PvACR3;1 transgenic rice accumulated 127%-205% higher As in the roots, with lower As translocation than wild type (WT) plants. In addition, at 20 µM of AsV, the transgenic rice showed similar results, indicating that expressing PvACR3;1 increased As retention in the roots from both AsIII and AsV. Furthermore, PvACR3;1 transgenic rice plants were grown in As-contaminated soils under flooded conditions. PvACR3;1 decreased As accumulations in transgenic rice shoots by 72%-83% without impacting nutrient minerals (Mn, Zn, and Cu). In addition, not only total As in unhusked rice grain of PvACR3;1 transgenic lines were decreased by 28%-39%, but also inorganic As was 26%-46% lower. Taken together, the results showed that expressing PvACR3;1 effectively decreased both total As and inorganic As in rice grain, which is of significance to breed low-As rice for food safety and human health.


Assuntos
Arsênico , Arsenitos , Oryza , Pteris , Poluentes do Solo , Antiporters , Humanos , Raízes de Plantas
14.
Environ Sci Technol ; 53(18): 10636-10644, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31411864

RESUMO

Arsenic-hyperaccumulator Pteris vittata is efficient in As accumulation and has been used in phytoremediation of As-contaminated soils. Arsenate (AsV) is the predominant As species in aerobic soils and is taken up by plants via phosphate transporters (Pht) including P. vittata. In this work, we cloned the PvPht1;3 full length coding sequence from P. vittata and investigated its role in As accumulation by yeast and plants. PvPht1;3 complemented a yeast P uptake mutant strain and showed a stronger affinity and transport capacity to AsV than PvPht1;2. In transgenic tobacco, PvPht1;3 enhanced AsV absorption and translocation, increasing As accumulation in the shoots under both hydroponic and soil experiments. On the basis of the expression patterns via qRT-PCR, PvPht1;3 was strongly induced by P deficiency but not As exposure. To further understand its expression pattern, transgenic Arabidopsis thaliana and soybean expressing the GUS reporter gene, driven by PvPht1;3 promoter, were produced. The GUS staining showed that the reporter gene was mainly expressed in the stele cells, indicating that PvPht1;3 was expressed in stele cells and was likely involved in P/As translocation. Taken together, the data suggested that PvPht1;3 was a high-affinity AsV transporter and was probably responsible for efficient As translocation in P. vittata. Our results suggest that expressing PvPht1;3 enhances As translocation and accumulation in plants, thereby improving phytoremediation of As-contaminated soils.


Assuntos
Arsênico , Pteris , Poluentes do Solo , Biodegradação Ambiental , Proteínas de Transporte de Fosfato , Raízes de Plantas , Tabaco
15.
Chemosphere ; 218: 1061-1070, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30609485

RESUMO

Arsenate (AsV) reduction in bacteria is essential to alleviate their arsenic (As) toxicity. We isolated a Bacillus strain PVR-YHB1-1 from the roots of As-hyperaccumulator Pteris vittata. The strain was efficient in reducing AsV to arsenite (AsIII), but the associated mechanisms were unclear. Here, we investigated its As resistance and reduction behaviors and associated genes at genome level. Results showed that the strain tolerated up to 20 mM AsV. When grown in 1 mM AsV, 96% AsV was reduced to AsIII in 48 h, with its AsV reduction ability being positively correlated to bacterial biomass. Two ars operons arsRacr3arsCDA and arsRKacr3arsC for As metabolisms were identified based on draft genome sequencing and gene annotations. Our data suggested that both operons might have attributed to efficient As resistance and AsV reduction in PVR-YHB1-1, providing clues to better understand As transformation in bacteria and their roles in As transformation in the environment.


Assuntos
Arseniatos/química , Arsênico/química , Bacillus/metabolismo , Genoma/genética , Arseniatos/análise
16.
Environ Pollut ; 241: 240-246, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29807282

RESUMO

While phosphate (P) inhibits arsenic (As) uptake by plants, phytate increases As uptake by As-hyperaccumulator Pteris vittata. Here we tried to understand the underling mechanisms by investigating the roles of phytate in soil As desorption, P transport in P. vittata, short-term As uptake, and plant growth and As accumulation from soils. Sterile soil was used to exclude microbial degradation on phytate. Results showed that inorganic P released 3.3-fold more As than that of phytate from soil. However, P. vittata accumulated 2-2.5 fold more As from soils with phytate than that in control and P treatment. In addition, different from P suppression on As uptake, solution uptake experiment showed that As uptake in phytate treatment was comparable to that of control under 0.1-7.5 µM As after 1-24 h. Moreover, responding to phytate, P. vittata P transporter PvPht1;3 increased by 3-fold while PvPht1;1 decreased by 65%. The data suggested that phytate upregulated PvPht1;3, thereby contributing to As uptake in P. vittata. Our results showed that, though with lower As release from soil compared to P, phytate induced more As uptake and better growth in P. vittata by upregulating P transporters.


Assuntos
Arsênico/metabolismo , Fósforo/metabolismo , Ácido Fítico/metabolismo , Pteris/metabolismo , Poluentes do Solo/metabolismo , Arsênico/análise , Biodegradação Ambiental , Fosfatos/metabolismo , Desenvolvimento Vegetal , Raízes de Plantas/metabolismo , Solo , Poluentes do Solo/análise
17.
Nature ; 556(7700): 255-258, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618817

RESUMO

Cross-species transmission of viruses from wildlife animal reservoirs poses a marked threat to human and animal health 1 . Bats have been recognized as one of the most important reservoirs for emerging viruses and the transmission of a coronavirus that originated in bats to humans via intermediate hosts was responsible for the high-impact emerging zoonosis, severe acute respiratory syndrome (SARS) 2-10 . Here we provide virological, epidemiological, evolutionary and experimental evidence that a novel HKU2-related bat coronavirus, swine acute diarrhoea syndrome coronavirus (SADS-CoV), is the aetiological agent that was responsible for a large-scale outbreak of fatal disease in pigs in China that has caused the death of 24,693 piglets across four farms. Notably, the outbreak began in Guangdong province in the vicinity of the origin of the SARS pandemic. Furthermore, we identified SADS-related CoVs with 96-98% sequence identity in 9.8% (58 out of 591) of anal swabs collected from bats in Guangdong province during 2013-2016, predominantly in horseshoe bats (Rhinolophus spp.) that are known reservoirs of SARS-related CoVs. We found that there were striking similarities between the SADS and SARS outbreaks in geographical, temporal, ecological and aetiological settings. This study highlights the importance of identifying coronavirus diversity and distribution in bats to mitigate future outbreaks that could threaten livestock, public health and economic growth.


Assuntos
Alphacoronavirus/isolamento & purificação , Alphacoronavirus/patogenicidade , Doenças dos Animais/epidemiologia , Doenças dos Animais/virologia , Quirópteros/virologia , Infecções por Coronavirus/veterinária , Diarreia/veterinária , Suínos/virologia , Alphacoronavirus/classificação , Alphacoronavirus/genética , Doenças dos Animais/transmissão , Animais , Biodiversidade , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Diarreia/patologia , Diarreia/virologia , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/virologia , Genoma Viral/genética , Humanos , Jejuno/patologia , Jejuno/virologia , Filogenia , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/veterinária , Síndrome Respiratória Aguda Grave/virologia , Análise Espaço-Temporal , Zoonoses/epidemiologia , Zoonoses/transmissão , Zoonoses/virologia
18.
Environ Sci Technol ; 52(7): 3975-3981, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29539263

RESUMO

Phosphorus is an important macronutrient for plant growth and is acquired by plants mainly as phosphate (P). Phosphate transporters (Phts) are responsible for P and arsenate (AsV) uptake in plants including arsenic-hyperaccumulator Pteris vittata. P. vittata is efficient in AsV uptake and P utilization, but the molecular mechanism of its P uptake is largely unknown. In this study, a P. vittata Pht, PvPht1;2, was cloned and transformed into tobacco ( Nicotiana tabacum). In hydroponic experiments, all transgenic lines displayed markedly higher P content and better growth than wild type, suggesting that PvPht1;2 mediated P uptake in plants. In addition, expressing PvPht1;2 also increased the shoot/root 32P ratio by 69-92% and enhanced xylem sap P by 46-62%, indicating that PvPht1;2 also mediated P translocation in plants. Unlike many Phts permeable to AsV, PvPht1;2 showed little ability to transport AsV. In soil experiments, PvPht1;2 also significantly increased shoot biomass without elevating As accumulation in PvPht1;2 transgenic tobacco. Taken together, our results demonstrated that PvPht1;2 is a specific P transporter responsible for P acquisition and translocation in plants. We envisioned that PvPht1;2 can enhance crop P acquisition without impacting AsV uptake, thereby increasing crop production without compromising food safety.


Assuntos
Arsênico , Pteris , Poluentes do Solo , Biodegradação Ambiental , Proteínas de Transporte de Fosfato , Fósforo , Raízes de Plantas
19.
Chemosphere ; 198: 425-431, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29421759

RESUMO

It is known that arsenic (As) promotes growth of As-hyperaccumulator Pteris vittata (PV), however, the associated mechanisms are unclear. Here we examined As-induced nutrient uptake in P. vittata and their potential role to enhance plant growth in sterile agar by excluding microbial effects. As-hyperaccumulator P. multifida (PM) and non-hyperaccumulator P. ensiformis (PE) belonging to the Pteris genus were used as comparisons. The results showed that, after 40 d of growth, As induced biomass increase in hyperaccumulators PV and PM by 5.2-9.4 fold whereas it caused 63% decline in PE. The data suggested that As played a beneficial role in promoting hyperaccumulator growth. In addition, hyperaccumulators PV and PM accumulated 7.5-13, 1.4-3.6, and 1.8-4.4 fold more As, Fe, and P than the non-hyperaccumulator PE. In addition, nutrient contents such as K and Zn were also increased while Ca, Mg, and Mn decreased or unaffected under As treatment. This study demonstrated that As promoted growth in hyperaccumulators and enhanced Fe, P, K, and Zn uptake. Different plant growth responses to As among hyperaccumulators PV and PM and non-hyperaccumulator PE may help to better understand why hyperaccumulators grow better under As-stress.


Assuntos
Arsênico/análise , Biodegradação Ambiental , Pteris/toxicidade , Poluentes do Solo/análise , Arsênico/metabolismo , Biomassa , Nitrogênio/metabolismo , Fósforo/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Raízes de Plantas/química , Pteris/efeitos dos fármacos , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade
20.
Environ Sci Technol ; 51(21): 12131-12138, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29024589

RESUMO

Arsenic (As) accumulation in rice grains poses health risk to humans. Plants including rice take up arsenate (AsV) by phosphate transporters. In this study, rice phosphate transporter OsPT4 (OsPht1;4) was investigated based on two independent T-DNA insertion mutants of OsPT4 (M1 and M2), which displayed stronger AsV resistance than wild types WT1 and WT2. When cultivated in medium (+P or -P) with AsV, ospt4 mutants accumulated 16-32% lower As in plants, suggesting that OsPT4 mediates AsV uptake. Analysis of the xylem sap showed that AsV concentrations in ospt4 mutants was 20-40% lower than WT controls under -P condition, indicating OsPT4 may also mediate AsV translocation. Moreover, kinetics analysis showed that ospt4 mutants had lower AsV uptake rates than the WT controls, further proving that OsPT4 functions as an AsV transporter in rice. When grown in flooded soils with As, AsV concentrations in rice grains of ospt4 mutants decreased by 50-55%. More importantly, knocking out OsPT4 in M1 and M2 reduced inorganic As accumulation in rice grains by 20-44%, significant for controlling As exposure risk from rice. Taken together, our findings revealed a critical role of OsPT4 in AsV uptake and translocation in rice. Knocking out OsPT4 effectively decreased inorganic As accumulation in rice grains, shedding light on engineering low-As rice to enhance food safety.


Assuntos
Arseniatos/farmacocinética , Oryza/genética , Proteínas de Plantas/genética , Arsênico , Transporte Biológico , Técnicas de Inativação de Genes , Humanos , Raízes de Plantas
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