Publications by authors named "Yongjing Guan"

In order to investigate the impact of environmental conditions on the distribution and migration of Sr in the Longji terrace environment, the activity concentrations of Sr and Cs were determined. The activity concentration ranges of Sr and Cs in surface soil were 0.15-1.

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Article Synopsis
  • China is facing significant ecological and economic threats from biological invasions, particularly from invasive alien species (IAS), with the Western mosquitofish (Gambusia affinis) being a key example.
  • This species is widely distributed in southern China and is moving northward, necessitating effective monitoring methods to understand its distribution and impact amidst climate change.
  • Using Maxent modeling combined with environmental DNA (eDNA) verification, researchers found that G. affinis is expected to thrive in various regions, and its presence has been confirmed in new areas, highlighting the influence of temperature, precipitation, and human activities on its spread.
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In order to investigate the Pu potential influence in the ocean, and develop a new method for rapidly monitoring radioactive pollution, the Pu spatial distribution in the South China Sea (SCS) and the Indian Ocean (IND) sediments is analyzed by SF-ICP-MS (ELEMENT 2). The inventory-weighted mean activities of Pu were 0.413 ± 0.

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To investigate the spatial distribution and source of plutonium isotopes in the Beibu Gulf, surface sediments were collected and analyzed using sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). The activities of Pu in surface sediments ranged from 0.012 to 0.

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The spatial and vertical distribution of Pu and Cs in the sediments of the Yellow River Delta was studied to evaluate the deposition dynamics in the Yellow River estuary from 1960s. The activity of Pu and Cs in sediment core ranged from 0.001 to 0.

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Overuse of antimicrobial agents are generally considered to be a key factor in the occurrence of antibiotic resistance bacteria (ARB). Nevertheless, it is unclear whether ARB can be induced by non-antibiotic chemicals such as nonsteroidal anti-inflammatory drug (NSAID). Thus, the objective of this study is to investigate whether NSAID diclofenac (DCF) promote the emergence of antibiotic resistance in Escherichia coli K12 MG1655.

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Radionuclides in environmental ecosystems have ecotoxicity and health impact on human and environment, so radioactive contamination has always been one of the global concerns. This study mainly focused on the radioactivity of mosses collected from the Leye Tiankeng Group in Guangxi. The activities of Pu measured by SF-ICP-MS and Cs measured by HPGe in moss and soil samples are as follows: 0-2.

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Most bacteria in the natural environment have a biofilm mode of life, which is intrinsically tolerant to antibiotics. While until now, the knowledge of biofilm formation by Acinetobacter johnsonii is not well understood. In this study, the characteristics and the effect of a sub-inhibitory concentration of antibiotic on A.

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The pristine river and urban river show an environmental gradient caused by anthropogenic impacts such as wastewater treatment plants and domestic wastewater discharges. Here, metagenomic and binning analyses unveiled antibiotic resistance genes (ARGs) profiles, their co-occurrence with metal resistance genes (MRGs) and mobile genetic elements (MGEs), and their host bacteria in water and Hemiculter leucisculus samples of the river. Results showed that the decrease of ARG abundances from pristine to anthropogenic regions was attributed to the reduction of the relative abundance of multidrug resistance genes in water microbiomes along the environmental gradient.

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Driven by anthropogenic pressure, Antibiotic resistance genes (ARGs) could transfer from the environmental resistome into human commensals or even pathogens. The transport of ARGs through aquatic ecosystems is crucial and has attracted attention. Here, we employed metagenomic and binning to compare ARGs profiles, their co-occurrence with metal resistance genes (MRGs) and mobile genetic elements (MGEs), and their hosts between pristine and anthropogenic influenced rivers and explore the ecological mechanisms underlying the dissemination of ARGs induced by anthropogenic activities.

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As a result of anthropogenic pollution, the nitrogen nutrients load in urban rivers has increased, potentially raising the risk of river eutrophication. Here, we studied how anthropogenic impacts alter nitrogen metabolism in river sediments by comparing the metagenomic function of microbial communities between relatively primitive and human-disturbed sediments. The contents of organic matter (OM), total nitrogen (TN), NO-N and NO-N were higher in primitive site than in polluted sites, which might be due to vegetation density, sediment type, hydrology, etc.

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Bisphenol-A (BPA) has been reported to disrupt blood-testis barrier (BTB) integrity in mammals. However, its effects on fish testis sertoli cell (SC) barrier and the underlying mechanisms have been largely unknown to date. To study the SC barrier toxicity induced by BPA, male rare minnows (Gobiocypris rarus) were exposed to 15 μg L   BPA for 7, 14 and 21 d.

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Plutonium isotopes in the coral were determined with chemical separation method using AG 1-X8 and AG-MP-1M anion exchange resins and sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) in order to elucidate the activity concentration and source of Pu around Weizhou land in Beibu Gulf, China. Furthermore, the activity concentrations of other radionuclides (U, Ra, Th, Cs, K and Pb) were measured by a HPGe spectrometer. The activity concentration of Pu in the coral is determined to be in the range of 8.

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Acinetobacter johnsonii is a potentially opportunistic pathogen widely distributed in nosocomial and natural environments, but little attention has been paid to this bacillus. Here A. johnsonii strains from Ba River with different pollution levels were isolated.

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Animals living in urban river systems play critical roles in the dissemination of microbiome and antibiotic resistance that poses a strong threat to public health. This study provides a comprehensive profile of microbiota and antibiotic resistance genes (ARGs) of sharpbelly (Hemiculter leucisculus) and the surrounding water from five sites along the Ba River. Results showed Proteobacteria, Firmicutes and Fusobacteria were the dominant bacteria in gut of H.

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Environmental stress such as nutrient deprivation across multiple fields in nature causes physiological and biochemical changes in organism. Understanding the potential epigenetic modulations to phenotypic variation upon nutrient deprivation stress is crucial for environmental assessments. Here, the methyl-cytosine at single-base resolution was mapped across the whole genome and the methylation patterns and methylation levels coordinated with transcript analysis were systemically elaborated in zebrafish embryonic fibroblast cells under serum starvation stress.

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The gut of aquatic animals was a significant niche for dissemination of antibiotic resistance genes (ARGs) and direct response of living conditions. In this study, the gut microbiota of goldfish Carassius auratus Linnaeus was sampled at 7 days and 21 days after treatment with tetracycline at 0.285 and 2.

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Here we reported the stress responses of nutrient deprivation and extended observation of autophagy, apoptosis, and DNA methylation in zebrafish embryonic fibroblast (ZF4) cells. Our results showed that serum deprivation resulted in the changes of cell shape and adherent ability, the suppressed cell growth and viability, and the inhibited proliferation and cell cycle. Besides, the appearance of lysosome and autophagosome/autolysosome with significantly increased expression of mRNAs (ulk1a, becn1, atg12, sqstm1, maplc3, and lamp1) and proteins (Atg12, Becn1, Sqstm1, and Lamp1) indicate the autophagic activity was boosted at initial stage but relatively weakened at 48 h of serum starvation.

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Background: Several recent studies have focused on microstructural changes in the trigeminal nerve in trigeminal neuralgia using diffusion tensor imaging (DTI). However, alterations after microvascular decompression (MVD) have rarely been investigated. Furthermore, the trigeminal nerve of asymptomatic individuals also presenting with neurovascular contact/compression (NVC) has not yet been studied.

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The microbial communities in freshwater have raised concerns about the ecosystem and human health. Many ecological environmental problems have been found in urban river because of the unreasonable use and long-term wastewater discharge. In this study, we explored the bacterial community composition, abundance of 14 antibiotics and 21 antibiotic resistance genes (ARGs), and water environment features in seven water samples and seven sediment samples from Ba River in Xi'an, China.

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Bisphenol A (BPA), a representative endocrine disrupting compound, exists ubiquitously in the aquatic environment. Several studies on fish have validated the role of BPA in the lipid metabolism. However, the action mechanisms of BPA on lipid metabolism have been little studied.

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Bisphenol A (BPA), an ubiquitous environmental endocrine disruptor chemical, disturbs the mRNA expressions of steroidogenic genes and subsequently steroid hormone synthesis in mammals and aquatic species. However, the underlying regulation mechanisms are barely understood, especially in fish. To explore the regulation mechanism, we exposed female rare minnow Gobiocypris rarus (G.

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The riverine system is usually considered as a natural reservoir of antibiotic resistance genes (ARGs) and more susceptible to anthropogenic activities. In this study, the occurrence and distribution of 14 antibiotics belonging to 7 categories together with 23 corresponding ARGs in Ba River of Xi'an China were investigated in March and July 2017. Sulfonamides, quinolones, macrolides and tetracyclines were detected in high frequencies ranged from 85.

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Rationale And Objectives: This study aimed to measure apparent diffusion coefficient (ADC) in Chinese patients with newly diagnosed multiple myeloma by whole-body diffusion-weighted magnetic resonance imaging (WB-DWI MRI) and assess the diagnostic accuracy of ADC in the discrimination of deep response to induction chemotherapy.

Materials And Methods: Seventeen patients underwent WB-DWI MRI before and after induction chemotherapy (week 20). DWI images and ADC maps were produced and 89 regions of interest were chosen.

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Hypertension has a profound influence on the structure and function of blood vessels. Cerebral vessels undergo both structural and functional changes in hypertensive animals. However, dynamic changes of cerebrovasculature and the factors involved in this process are largely unknown.

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