RESUMO
Soil salinization poses a significant global challenge, exerting adverse effects on both agriculture and ecosystems. Planting halophytes has the potential ability to improve saline-alkali land and enhance ecosystem multifunctionality (EMF). However, it remains unclear which halophytes are effective in improving saline-alkali land and what impact they have on the rhizosphere microbial communities and EMF. In this study, we evaluated the Na+ absorption capability of five halophytes (Grubovia dasyphylla, Halogeton glomeratus, Suaeda salsa, Bassia scoparia, and Reaumuria songarica) and assessed their rhizosphere microbial communities and EMF. The results showed that S. salsa possessed the highest shoot (3.13 mmol g-1) and root (0.92 mmol g-1) Na+ content, and its soil Na+ absorption, along with B. scoparia, was significantly higher than that of other plants. The soil pH, salinity, and Na+ content of the halophyte rhizospheres decreased by 6.21%, 23.49%, and 64.29%, respectively, when compared to the bulk soil. Extracellular enzymes in the halophyte rhizosphere soil, including α-glucosidase, ß-glucosidase, ß-1,4-N-acetyl-glucosaminidase, neutral phosphatase, and alkaline phosphatase, increased by 70.1%, 78.4%, 38.5%, 79.1%, and 64.9%, respectively. Furthermore, the halophyte rhizosphere exhibited higher network complexity of bacteria and fungi and EMF than bulk soil. The relative abundance of the dominant phyla Proteobacteria, Firmicutes, and Ascomycota in the halophyte rhizosphere soil increased by 9.4%, 8.3%, and 22.25%, respectively, and showed higher microbial network complexity compared to the bulk soil. Additionally, keystone taxa, including Muricauda, Nocardioides, and Pontibacter, were identified with notable effects on EMF. This study confirmed that euhalophytes are the best choice for saline-alkali land restoration. These findings provided a theoretical basis for the sustainable use of saline-alkali cultivated land.
Assuntos
Rizosfera , Salinidade , Plantas Tolerantes a Sal , Microbiologia do Solo , Solo , Plantas Tolerantes a Sal/crescimento & desenvolvimento , Plantas Tolerantes a Sal/microbiologia , Solo/química , Ecossistema , MicrobiotaRESUMO
Ultra-precise reflectors in the advanced light source facilities urgently call for local slope error measurements with nano-radian precision. However, the existing methods currently utilized in the long trace profiler systems struggle to meet the requirements. In this paper, we present a weak-value amplification enhanced absolute local slope measurement scheme, in which the surface height difference between two adjacent points can be measured directly with precision on the pico-meter level. As a result, the absolute local slope measurement reaches a record precision level of 9.7 nrad (RMS) with a small lateral separation of 0.5 mm. Comparing to the existing methods, our scheme is more disturbance-resistant, more compact and cost-effective. The local curvature measuring capability is also validated with two synchronously parallel local slope measurement paths, between which the separation is set as 2mm. A local curvature measurement is obtained with precision of 3.4 × 10-6m-1 (RMS) and its corresponding slope variation is 6.8 nrad. Our method exhibits important application prospects in the field of ultra-precise surface fabrication inspection.
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The 2002-3 pandemic caused by severe acute respiratory syndrome coronavirus (SARS-CoV) was one of the most significant public health events in recent history. An ongoing outbreak of Middle East respiratory syndrome coronavirus suggests that this group of viruses remains a key threat and that their distribution is wider than previously recognized. Although bats have been suggested to be the natural reservoirs of both viruses, attempts to isolate the progenitor virus of SARS-CoV from bats have been unsuccessful. Diverse SARS-like coronaviruses (SL-CoVs) have now been reported from bats in China, Europe and Africa, but none is considered a direct progenitor of SARS-CoV because of their phylogenetic disparity from this virus and the inability of their spike proteins to use the SARS-CoV cellular receptor molecule, the human angiotensin converting enzyme II (ACE2). Here we report whole-genome sequences of two novel bat coronaviruses from Chinese horseshoe bats (family: Rhinolophidae) in Yunnan, China: RsSHC014 and Rs3367. These viruses are far more closely related to SARS-CoV than any previously identified bat coronaviruses, particularly in the receptor binding domain of the spike protein. Most importantly, we report the first recorded isolation of a live SL-CoV (bat SL-CoV-WIV1) from bat faecal samples in Vero E6 cells, which has typical coronavirus morphology, 99.9% sequence identity to Rs3367 and uses ACE2 from humans, civets and Chinese horseshoe bats for cell entry. Preliminary in vitro testing indicates that WIV1 also has a broad species tropism. Our results provide the strongest evidence to date that Chinese horseshoe bats are natural reservoirs of SARS-CoV, and that intermediate hosts may not be necessary for direct human infection by some bat SL-CoVs. They also highlight the importance of pathogen-discovery programs targeting high-risk wildlife groups in emerging disease hotspots as a strategy for pandemic preparedness.
Assuntos
Quirópteros/virologia , Peptidil Dipeptidase A/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/isolamento & purificação , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/metabolismo , Enzima de Conversão de Angiotensina 2 , Animais , China , Chlorocebus aethiops , Reservatórios de Doenças/virologia , Fezes/virologia , Imunofluorescência , Genoma Viral/genética , Especificidade de Hospedeiro , Humanos , Dados de Sequência Molecular , Pandemias/prevenção & controle , Pandemias/veterinária , Peptidil Dipeptidase A/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Virais/genética , Receptores Virais/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/ultraestrutura , Síndrome Respiratória Aguda Grave/prevenção & controle , Síndrome Respiratória Aguda Grave/transmissão , Síndrome Respiratória Aguda Grave/veterinária , Síndrome Respiratória Aguda Grave/virologia , Especificidade da Espécie , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Vero , Vírion/isolamento & purificação , Vírion/ultraestrutura , Internalização do Vírus , Viverridae/metabolismoRESUMO
Fusobacterium nucleatum can bind to host cells and potentiate intestinal tumorigenesis. Here we used a genome-wide screen to identify an adhesin, RadD, which facilitates the attachment of F. nucleatum to colorectal cancer (CRC) cells in vitro. RadD directly binds to CD147, a receptor overexpressed on CRC cell surfaces, which initiated a PI3K-AKT-NF-κB-MMP9 cascade, subsequently enhancing tumorigenesis in mice. Clinical specimen analysis showed that elevated radD gene levels in CRC tissues correlated positively with activated oncogenic signalling and poor patient outcomes. Finally, blockade of the interaction between RadD and CD147 in mice effectively impaired F. nucleatum attachment and attenuated F. nucleatum-induced oncogenic response. Together, our study provides insights into an oncogenic mechanism driven by F. nucleatum RadD and suggests that the RadD-CD147 interaction could be a potential therapeutic target for CRC.
Assuntos
Adesinas Bacterianas , Aderência Bacteriana , Basigina , Carcinogênese , Neoplasias Colorretais , Fusobacterium nucleatum , Fusobacterium nucleatum/patogenicidade , Fusobacterium nucleatum/genética , Fusobacterium nucleatum/fisiologia , Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/patologia , Animais , Humanos , Camundongos , Basigina/metabolismo , Basigina/genética , Adesinas Bacterianas/metabolismo , Adesinas Bacterianas/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Infecções por Fusobacterium/microbiologia , Infecções por Fusobacterium/complicações , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Transdução de Sinais , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/genética , FemininoRESUMO
Various stresses, including pressure overload and myocardial stretch, can trigger cardiac remodeling and result in heart diseases. The disorders are associated with high risk of morbidity and mortality and are among the major health problems in the world. MicroRNAs, a class of ~22nt-long small non-coding RNAs, have been found to participate in regulating heart development and function. One of them, miR-208a, a cardiac-specific microRNA, plays key role(s) in modulating gene expression in the heart, and is involved in a broad array of processes in cardiac pathogenesis. Genetic deletion or pharmacological inhibition of miR-208a in rodents attenuated stress-induced cardiac hypertrophy and remodeling. Transgenic expression of miR-208a in the heart was sufficient to cause hypertrophic growth of cardiomyocytes. miR-208a is also a key regulator of cardiac conduction system, either deletion or transgenic expression of miR-208a disturbed heart electrophysiology and could induce arrhythmias. In addition, miR-208a appeared to assist in regulating the expression of fast- and slow-twitch myofiber genes in the heart. Notably, this heart-specific miRNA could also modulate the "endocrine" function of cardiac muscle and govern the systemic energy homeostasis in the whole body. Despite of the critical roles, the underlying regulatory networks involving miR-208a are still elusive. Here, we summarize the progress made in understanding the function and mechanisms of this important miRNA in the heart, and propose several topics to be resolved as well as the hypothetical answers. We speculate that miR-208a may play diverse and even opposite roles by being involved in distinct molecular networks depending on the contexts. A deeper understanding of the precise mechanisms of its action under the conditions of cardiac homeostasis and diseases is needed. The clinical implications of miR-208a are also discussed.
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OBJECTIVES: Shotgun metagenomic sequencing of human fecal samples has shown that Saccharomyces cerevisiae (S. cerevisiae) is significantly suppressed in colorectal cancer (CRC) and probably plays an important role in CRC progression. However, these results need to be validated. Here we aimed to confirm the results of high-throughput sequencing and demonstrate the mechanisms mediating the effect of S. cerevisiae on progression from colorectal adenoma (CRA) to CRC. METHODS: We used a quantitative polymerase chain reaction (qPCR) assay to examine the relative abundance of S. cerevisiae in 281 fecal samples collected from 106 healthy controls, 108 patients with CRA and 67 with CRC. C57BL/6 and APCMin/+ mouse models and in vitro cell assays were subsequntly used for additional analyses. The mouse models were treated or not treated with broad-spectrum antibiotics and given an S. cerevisiae gavage for 8 weeks. Western blot, 16S rRNA sequencing, qPCR, immunohistochemistry, RNA sequencing, cell counting kit-8 assay, colony formation assay and flow cytometry were performed. RESULTS: S. cerevisiae was 2.68-fold and 3.94-fold less abundant in patients with CRA and CRC, respectively, than in the controls. In vivo experiments showed that S. cerevisiae reduced colorectal tumor progression by promoting epithelial cell apoptosis and modulated gut microbial structure and intestinal immunity. S. cerevisiae downregulated nuclear factor kappa light chain enhancer of activated B cells and the mechanistic target of rapamycin signaling pathways. Cell assays confirmed the pro-apoptotic effect of S. cerevisiae. CONCLUSIONS: S. cerevisiae may play a probiotic role in CRC by promoting cancer cell apoptosis. It can reduce CRC progression by modulating the mucosal microbial structure.
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Apoptose , Neoplasias Colorretais , Probióticos , Saccharomyces cerevisiae , Animais , Proliferação de Células , Neoplasias Colorretais/terapia , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16SRESUMO
The aim of this study was to explore the pollution level and potential ecological risk of heavy metals in sediments of the Danjiangkou Reservoir, and the study obtained the background value of heavy metals of the surface sediments using reference element and statistical methods. The results indicated that the background values of Cr, Ni, Cu, Zn, As, Cd, Hg and Pb were 41.18, 34, 32.13, 76.84, 10.46, 0.70, 0.07 and 27.11 mg·kg-1, respectively. In addition, the potential ecological risks of the eight heavy metals in sediments were assessed using the Hakanson ecological risk index method. The values of RI for these eight metals in surface sediments ranged from 29.49 to 214.11, with the mean value of 118.91, and the pollution level was low. Furthermore, the Cfi value was in the order of Cd> Hg> Zn> Cr> Pb> Ni> As=Cu with the mean value of 1.05-1.31, and the pollution level varied from low to intermediate. The Cfi values of Cd and Hg were higher than those of other heavy metals with the mean values of 1.31 and 1.24, respectively, which should be paid more attentions.
Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , China , Medição de RiscoRESUMO
OBJECTIVE: To investigate the expression of miR-126/miR-126* in hepatocellular carcinoma (HCC) tissues and its clinical significance. METHODS: The expressions of miR-126/miR-126* in the tumor tissues and non-cancer tissues from 74 HCC cases were detected using real-time quantitative PCR. The correlation between miR-126/miR-126* expression and the clinicopathological features of the patients was analyzed. RESULTS: Compared with the non-cancer tissues, HCC tissues showed significantly lowered expression levels of miR-126/miR-126*. A positive correlation was found between the expressions of miR-126 and miR-126* in the tumor tissues. Lower expressions of miR-126/miR-126* were significantly correlated with tumor recurrence and poor survival of the HCC patients. CONCLUSION: The down-regulation of miR-126/miR-126* may play an important role in HCC metastasis and contributes to poor survival of HCC patients.