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1.
Pestic Biochem Physiol ; 201: 105902, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685224

RESUMO

CRF-like diuretic hormone receptor (CRF/DHR), also known as DH44R in insects, are G-protein coupled receptors (GPCRs) that play a role in regulating osmotic balance in various insect species. These receptors have the potential to be targeted for the development of insecticides. However, our understanding of the role of DHR genes in aphids, including Rhopalosiphum padi, a major wheat pest, is currently limited. In this study, we isolated and characterized two R. padi DHRs (RpDHR1 and RpDHR2). The expression levels of RpDHR1 increased after starvation and were restored after re-feeding. The expression levels of RpDHR1 gene decreased significantly 24 h after injection of dsRNA targeting the gene. Knockdown of RpDHR1 increased aphid mortality under starvation conditions (24, 36, 48 and 60 h). Under starvation and desiccation condition, the aphid mortality decreased after knockdown of RpDHR1. This is the first study to report the role of DHR genes in the starvation and desiccation response of aphids. The results suggest that RpDHR1 is involved in the resistance of R. padi to starvation and dehydration, making it a potential target for insecticide development. Novel insecticides could be created by utilizing DHR agonists to disrupt the physiological processes of insect pests.


Assuntos
Afídeos , Proteínas de Insetos , Animais , Afídeos/genética , Afídeos/fisiologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Inanição/genética , Dessecação , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Filogenia
2.
BMC Bioinformatics ; 24(1): 249, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37312038

RESUMO

BACKGROUND: Closing gaps in draft genomes leads to more complete and continuous genome assemblies. The ubiquitous genomic repeats are challenges to the existing gap-closing methods, based on either the k-mer representation by the de Bruijn graph or the overlap-layout-consensus paradigm. Besides, chimeric reads will cause erroneous k-mers in the former and false overlaps of reads in the latter. RESULTS: We propose a novel local assembly approach to gap closing, called RegCloser. It represents read coordinates and their overlaps respectively by parameters and observations in a linear regression model. The optimal overlap is searched only in the restricted range consistent with insert sizes. Under this linear regression framework, the local DNA assembly becomes a robust parameter estimation problem. We solved the problem by a customized robust regression procedure that resists the influence of false overlaps by optimizing a convex global Huber loss function. The global optimum is obtained by iteratively solving the sparse system of linear equations. On both simulated and real datasets, RegCloser outperformed other popular methods in accurately resolving the copy number of tandem repeats, and achieved superior completeness and contiguity. Applying RegCloser to a plateau zokor draft genome that had been improved by long reads further increased contig N50 to 3-fold long. We also tested the robust regression approach on layout generation of long reads. CONCLUSIONS: RegCloser is a competitive gap-closing tool. The software is available at https://github.com/csh3/RegCloser . The robust regression approach has a prospect to be incorporated into the layout module of long read assemblers.


Assuntos
Genômica , Software , Consenso , Modelos Lineares , Sequências de Repetição em Tandem
3.
Bioinformatics ; 38(10): 2675-2682, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35561180

RESUMO

MOTIVATION: Crucial to the correctness of a genome assembly is the accuracy of the underlying scaffolds that specify the orders and orientations of contigs together with the gap distances between contigs. The current methods construct scaffolds based on the alignments of 'linking' reads against contigs. We found that some 'optimal' alignments are mistaken due to factors such as the contig boundary effect, particularly in the presence of repeats. Occasionally, the incorrect alignments can even overwhelm the correct ones. The detection of the incorrect linking information is challenging in any existing methods. RESULTS: In this study, we present a novel scaffolding method RegScaf. It first examines the distribution of distances between contigs from read alignment by the kernel density. When multiple modes are shown in a density, orientation-supported links are grouped into clusters, each of which defines a linking distance corresponding to a mode. The linear model parameterizes contigs by their positions on the genome; then each linking distance between a pair of contigs is taken as an observation on the difference of their positions. The parameters are estimated by minimizing a global loss function, which is a version of trimmed sum of squares. The least trimmed squares estimate has such a high breakdown value that it can automatically remove the mistaken linking distances. The results on both synthetic and real datasets demonstrate that RegScaf outperforms some popular scaffolders, especially in the accuracy of gap estimates by substantially reducing extremely abnormal errors. Its strength in resolving repeat regions is exemplified by a real case. Its adaptability to large genomes and TGS long reads is validated as well. AVAILABILITY AND IMPLEMENTATION: RegScaf is publicly available at https://github.com/lemontealala/RegScaf.git. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Software , Mapeamento de Sequências Contíguas/métodos , Genoma , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos
4.
Analyst ; 148(5): 1068-1074, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36752351

RESUMO

A one-step strategy for synthesizing fluorescent copper clusters stabilized by L-cysteine has been successfully established in aqueous solutions. The direct determination of copper ions was realized by the fluorescence enhancement phenomenon caused by the preparation and aggregation process. At the same time, ammonia treatment can lead to rapid fluorescence quenching, resulting from the influence on the aggregation behavior of Cu clusters, while the fluorescence can be recovered by the continuous addition of copper ions. Therefore, a recyclable fluorescence sensing system is constructed for the simultaneous determination of copper ions and ammonia. This method is simple, anti-interference and has been successfully applied to the determination of environmental samples.

5.
BMC Infect Dis ; 23(1): 679, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37821841

RESUMO

BACKGROUND: The emergency of new COVID-19 variants over the past three years posed a serious challenge to the public health. Cities in China implemented mass daily RT-PCR tests by pooling strategies. However, a random delay exists between an infection and its first positive RT-PCR test. It is valuable for disease control to know the delay pattern and daily infection incidences reconstructed from RT-PCR test observations. METHODS: We formulated the convolution model between daily incidences and positive RT-PCR test counts as a linear inverse problem with positivity restrictions. Consequently, the Richard-Lucy deconvolution algorithm was used to reconstruct COVID-19 incidences from daily PCR tests. A real-time deconvolution was further developed based on the same mathematical principle. The method was applied to an Omicron epidemic data set of a bar outbreak in Beijing and another in Wuxi in June 2022. We estimated the delay function by maximizing likelihood via an E-M algorithm. RESULTS: The delay function of the bar-outbreak in 2022 differs from that reported in 2020. Its mode was shortened to 4 days by one day. A 95% confidence interval of the mean delay is [4.43,5.55] as evaluated by bootstrap. In addition, the deconvolved infection incidences successfully detected two associated infection events after the bar was closed. The application of the real-time deconvolution to the Wuxi data identified all explosive incidence increases. The results revealed the progression of the two COVID-19 outbreaks and provided new insights for prevention and control strategies, especially for the role of mass daily RT-PCR testing. CONCLUSIONS: The proposed deconvolution method is generally applicable to other infectious diseases if the delay model can be assumed to be approximately valid. To ensure a fair reconstruction of daily infection incidences, the delay function should be estimated in a similar context in terms of virus variant and test protocol. Both the delay estimate from the E-M algorithm and the incidences resulted from deconvolution are valuable for epidemic prevention and control. The real-time feedback is particularly useful during the epidemic's acute phase because it can help the local disease control authorities modify the control measures more promptly and precisely.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , SARS-CoV-2/genética , Incidência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Teste para COVID-19
6.
J Gastroenterol Hepatol ; 38(3): 468-475, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36653317

RESUMO

BACKGROUND AND AIM: Severe acute pancreatitis (SAP) in patients progresses rapidly and can cause multiple organ failures associated with high mortality. We aimed to train a machine learning (ML) model and establish a nomogram that could identify SAP, early in the course of acute pancreatitis (AP). METHODS: In this retrospective study, 631 patients with AP were enrolled in the training cohort. For predicting SAP early, five supervised ML models were employed, such as random forest (RF), K-nearest neighbors (KNN), and naive Bayes (NB), which were evaluated by accuracy (ACC) and the areas under the receiver operating characteristic curve (AUC). The nomogram was established, and the predictive ability was assessed by the calibration curve and AUC. They were externally validated by an independent cohort of 109 patients with AP. RESULTS: In the training cohort, the AUC of RF, KNN, and NB models were 0.969, 0.954, and 0.951, respectively, while the AUC of the Bedside Index for Severity in Acute Pancreatitis (BISAP), Ranson and Glasgow scores were only 0.796, 0.847, and 0.837, respectively. In the validation cohort, the RF model also showed the highest AUC, which was 0.961. The AUC for the nomogram was 0.888 and 0.955 in the training and validation cohort, respectively. CONCLUSIONS: Our findings suggested that the RF model exhibited the best predictive performance, and the nomogram provided a visual scoring model for clinical practice. Our models may serve as practical tools for facilitating personalized treatment options and improving clinical outcomes through pre-treatment stratification of patients with AP.


Assuntos
Pancreatite , Humanos , Estudos Retrospectivos , Nomogramas , Índice de Gravidade de Doença , Doença Aguda , Teorema de Bayes , Prognóstico , Aprendizado de Máquina
7.
Allergol Immunopathol (Madr) ; 51(4): 175-181, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37422795

RESUMO

BACKGROUND: Asthma is a common lung disease with increasing incidence and prevalence globally, thereby imposing a substantial global health and economic burden. Recently, studies have shown that Mitsugumin 53 (MG53) exhibits multiple biological functions and plays a protective role in a variety of diseases. However, the role of MG53 in asthma remained unknown; hence, in the present study we aimed to explore the functioning of MG53 in asthma. METHODS: Using ovalbumin and aluminum hydroxide adjuvant, an OVA-induced asthmatic animal model was constructed and administered with MG53. After establishing mice model, inflammatory cell counts and the levels of type 2 inflammatory cytokines were examined and histological staining of lung tissues were performed. The levels of key factors associated with the nuclear factor-κB (NF-κB) pathway were detected. RESULTS: Asthmatic mice displayed a remarkable accumulation of white blood cells, neutrophils, macrophages, lymphocytes, and eosinophils in bronchoalveolar lavage fluid, compared to control mice. MG53 treatment lowered the number of these inflammatory cells in asthmatic mice. The level of type 2 cytokines in asthmatic mice was higher than that in control mice, and was lessened by MG53 intervention. In asthmatic mice, airway resistance was elevated, which was reduced by MG53 treatment. In addition, inflammatory cell infiltration and mucus secretion were aggravated in the lung tissues of asthmatic mice, and both were attenuated by MG53 intervention. The levels of phosphorylated p65 and phosphorylated inhibitor of nuclear factor kappa-B kinase were elevated in asthmatic mice, but were downregulated by MG53 supplement. CONCLUSION: The aggravated airway inflammation was observed in asthmatic mice; however, MG53 treatment suppressed airway inflammation by targeting the NF-κB pathway.


Assuntos
Asma , NF-kappa B , Camundongos , Animais , NF-kappa B/metabolismo , Pulmão/patologia , Líquido da Lavagem Broncoalveolar , Inflamação/patologia , Citocinas/metabolismo , Camundongos Endogâmicos BALB C , Ovalbumina , Modelos Animais de Doenças , Proteínas de Membrana/metabolismo
8.
Pestic Biochem Physiol ; 194: 105528, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532337

RESUMO

Uridine diphosphate-glucuronosyltransferases (UGTs) are major multifunctional detoxification phase II enzymes involved in the metabolic detoxification of xenobiotics. However, their roles in insecticides resistance are still unclear. In this study, we identified two UGTs genes (UGT2B13 and UGT2C1) in Rhopalosiphum padi, a serious insect pest of wheat worldwide. Bioassays results showed that the resistance ratio of R. padi resistance strain (LC-R) to lambda-cyhalothrin (LC) was 2963.8 fold. The roles of UGT2B13 and UGT2C1 in lambda-cyhalothrin resistance were evaluated. Results indicated that the UGTs contents were significantly increased in the LC resistant strain of R. padi. UGT2B13 and UGT2C1 were significantly overexpressed in the LC-R strain. Transcription levels of UGT2B13 and UGT2C1 were relatively higher in the gut of LC-R strain. RNA interference (RNAi) of UGT2B13 or UGT2C1 significantly decreased the UGTs contents of the LC-R aphids and increased mortality of R. padi exposure to the LC50 concentration of LC. This study provides a new view that UGTs are involved in LC resistance of R. padi. The findings will promote further work to detailed the functions of UGTs in the metabolism resistance of insects to insecticides.


Assuntos
Afídeos , Inseticidas , Piretrinas , Animais , Inseticidas/farmacologia , Piretrinas/farmacologia , Nitrilas/farmacologia , Resistência a Inseticidas/genética
9.
Analyst ; 147(6): 1071-1075, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35195636

RESUMO

Femto flow electrospray ionization (ESI) with flow rates ranging from 240 fL min-1 to the low pico level (<10 pL min-1) was conducted and measured using a submicron emitter tip and relay ESI configuration. Signature analyte ion current intensities and profiles were observed. The obtained flow rate and ionization current enabled size calculation for initial charged nanodroplets.

10.
Biochem J ; 476(15): 2239-2254, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31341009

RESUMO

Protein lysine acetylation is one of the major posttranslational modifications (PTMs) with several thousands of proteins identified to be acetylated in mammalian tissues. Mechanistic studies have revealed important functions of acetylation in the regulation of protein function. Much less is known on how the acetyltransferases themselves are regulated. In the current study, we discover that the Elongator protein 3 (ELP3) acetyltransferase is modified by tyrosine phosphorylation. We demonstrate that the anaplastic lymphoma kinase (ALK) is the major tyrosine kinase responsible for ELP3 tyrosine phosphorylation. ELP3 is phosphorylated in tumor cells expressing oncogenic NPM-ALK fusion protein. We further identify Tyr202 as the major ALK phosphorylation site in ELP3. Importantly, the introduction of Y202 phosphorylation mutant ELP3 into ALK-positive tumor cells reduced cell growth and impaired gene expression. Collectively, our study reveals a novel regulatory mechanism for ELP3, provides an example that acetyltransferase itself can be regulated by PTM, and suggests a potential target for ALK-positive cancer therapies.


Assuntos
Histona Acetiltransferases/metabolismo , Neoplasias/enzimologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Tirosina Quinases/metabolismo , Substituição de Aminoácidos , Células HCT116 , Células HEK293 , Histona Acetiltransferases/genética , Humanos , Mutação de Sentido Incorreto , Neoplasias/genética , Neoplasias/patologia , Proteínas do Tecido Nervoso/genética , Proteínas de Fusão Oncogênica/genética , Fosforilação , Proteínas Tirosina Quinases/genética
11.
Anal Chem ; 91(11): 7001-7006, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31055933

RESUMO

A miniaturized optical emission spectrometer was constructed with improved point discharge microplasma as an excitation source to enhance sample introduction efficiency and excitation efficiency. By using a hollow electrode as one of the discharge electrodes, analyte-containing chemical vapor yielded via hydride generation was transported and confined into the hollow electrode and subsequently guided into the microplasma with high sample introduction efficiency. Moreover, gaseous analyte species were directly diffused from inside the electrode into the center of the microplasma, instead of traditional external diffusion into the microplasma, resulting in sufficient participation in interactions and excitation in the plasma; thus, high excitation efficiency and stability can be achieved. A 3D-printing technique was used to fabricate some components for compact integration of this spectrometer. Physical characteristics of the microplasma, 3D-printing, and experimental parameters were all investigated to better understand the excitation capability and obtain optimal analytical performance. Under optimized conditions, As, Bi, Ge, Hg, Pb, Sb, Se, and Sn were successfully detected, with detection limits of 2.5, 0.44, 1.6, 0.10, 2.8, 1.5, 31, and 0.24 µg L-1, respectively, and relative standard deviations all less than 4%. It was applied to the analysis of Certified Reference Materials (water, soil, and biological samples) and real water samples with satisfactory results. Because of its advantages of compactness, robustness, easy fabrication, and cost-effectiveness, it has a great prospect as a portable spectrometer for field analytical chemistry.

12.
J Biol Chem ; 291(36): 18947-58, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27382053

RESUMO

The thromboxane A2 receptor (TP) has been implicated in restenosis after vascular injury, which induces vascular smooth muscle cell (VSMC) migration and proliferation. However, the mechanism for this process is largely unknown. In this study, we report that TP signaling induces VSMC migration and proliferation through activating YAP/TAZ, two major downstream effectors of the Hippo signaling pathway. The TP-specific agonists [1S-[1α,2α(Z),3ß(1E,3S*),4 α]]-7-[3-[3-hydroxy-4-(4-iodophenoxy)-1-butenyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid (I-BOP) and 9,11-dideoxy-9α,11α-methanoepoxy-prosta-5Z,13E-dien-1-oic acid (U-46619) induce YAP/TAZ activation in multiple cell lines, including VSMCs. YAP/TAZ activation induced by I-BOP is blocked by knockout of the receptor TP or knockdown of the downstream G proteins Gα12/13 Moreover, Rho inhibition or actin cytoskeleton disruption prevents I-BOP-induced YAP/TAZ activation. Importantly, TP activation promotes DNA synthesis and cell migration in VSMCs in a manner dependent on YAP/TAZ. Taken together, thromboxane A2 signaling activates YAP/TAZ to promote VSMC migration and proliferation, indicating YAP/TAZ as potential therapeutic targets for cardiovascular diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Fosfoproteínas/metabolismo , Transdução de Sinais/fisiologia , Tromboxano A2/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Ácidos Graxos Insaturados/farmacologia , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/genética , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/metabolismo , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Fosfoproteínas/genética , Receptores de Tromboxano A2 e Prostaglandina H2/agonistas , Receptores de Tromboxano A2 e Prostaglandina H2/genética , Receptores de Tromboxano A2 e Prostaglandina H2/metabolismo , Tromboxano A2/genética , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas de Sinalização YAP
13.
Biotechnol Lett ; 36(2): 295-300, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24068509

RESUMO

L-2-Hydroxyacid dehydrogenase (HDH) from Ketogulonicigenium vulgare Y25 was cloned and overexpressed in Escherichia coli. The protein was purified and crystallized by the sitting-drop vapour-diffusion method with polyethylene glycol 3350 as precipitant. The crystal structure of HDH was determined at 1.64 Å resolution using the molecular replacement method with the crystal structure of hydroxyl (phenyl) pyruvate reductase from Coleus blumei Benth as the search model. The overall structure of HDH was similar to that of hydroxyl(phenyl)pyruvate reductase, consisting of two compact domains separated by a deep active cleft. The most significant structural divergence is located around the pocket gate comprising residues A210, T211 and R212, which is located on top of the catalytic triad.


Assuntos
Oxirredutases do Álcool/química , Cristalização , Rhodobacteraceae/enzimologia , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/isolamento & purificação , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Expressão Gênica , Modelos Moleculares , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Rhodobacteraceae/química
14.
Ann Biomed Eng ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705931

RESUMO

Advanced glycation end products (AGEs) have garnered significant attention due to their association with chronic diseases and the aging process. The prevalence of geriatric diseases among young individuals has witnessed a notable surge in recent years, potentially attributed to the accelerated pace of modern life. The accumulation of AGEs is primarily attributed to their inherent difficulty in metabolism, which makes them promising biomarkers for chronic disease detection. This review aims to provide a comprehensive overview of the recent advancements and findings in AGE research. The discussion is divided into two main sections: endogenous AGEs (formed within the body) and exogenous AGEs (derived from external sources). Various aspects of AGEs are subsequently summarized, including their production pathways, pathogenic mechanisms, and detection methods. Moreover, this review delves into the future research prospects concerning AGEs. Overall, this comprehensive review underscores the importance of AGEs in the detection of chronic diseases and provides a thorough understanding of their significance. It emphasizes the necessity for further research endeavors to deepen our comprehension of AGEs and their implications for human health.

15.
Insect Sci ; 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38282241

RESUMO

Many aphid species exhibit both cyclical parthenogenesis (CP) and the obligate parthenogenesis (OP) life history, which are genetically determined. In CP aphid lineages, the parthenogenetic individuals can switch from asexual to sexual reproduction quickly in response to environmental factors such as changes in photoperiod and temperature. However, the OP aphid lineages do not undergo sexual reproduction under any conditions. So far, mechanisms underlying the reproduction switch in CP aphids have not been fully elucidated. Rhopalosiphum padi, a serious worldwide insect pest of wheat, has both CP and OP lineages. Uridine diphosphate-glycosyltransferases (UGTs) are enzymes that participate in the metabolic detoxification of xenobiotics. Here, we identified 43 RpUGT genes from R. padi genome and transcriptome sequences, and found that: (1) the UGT content of the CP lineage was significantly higher than that in the OP lineage at the key time points when CP lineage mainly produce virginoparae, gynoparae, and males under inducing condition, while there were no significant difference under normal conditions; (2) RpUGT344J7 gene was highly expressed during the time points when CP lineages produce gynopara and males; (3) the critical time points for CP lineages to produce virginoparaee, gynoparae, and males were affected when the CP lineages were injected with dsRpUGT344J7; (4) the knockdown of RpUGT344J7 caused a significant reduction in the total number of virginoparae, gynoparae, and males in the offspring under inducing condition. The findings contribute to our understanding of the molecular mechanisms underlying the quick shift from asexual to sexual reproduction in aphid species.

16.
J Agric Food Chem ; 72(10): 5165-5175, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38437009

RESUMO

Uridine diphosphate-glycosyltransferase (UGT) is a key phase II enzyme in the insect detoxification system. Pyrethroids are commonly used to control the destructive wheat aphid Rhopalosiphum padi. In this study, we found a highly expressed UGT gene, RpUGT344D38, in both λ-cyhalothrin (LCR)- and bifenthrin (BTR)-resistant strains of R. padi. After exposure to λ-cyhalothrin and bifenthrin, the expression levels of RpUGT344D38 were significantly increased in the resistant strains. Knockdown of RpUGT344D38 did not affect the resistance of BTR, but it did significantly increase the susceptibility of LCR aphids to λ-cyhalothrin. Molecular docking analysis demonstrated that RpUGT344D38 had a stable binding interaction with both bifenthrin and λ-cyhalothrin. The recombinant RpUGT344D38 was able to metabolize 50% of λ-cyhalothrin. This study provides a comprehensive analysis of the role of RpUGT344D38 in the resistance of R. padi to bifenthrin and λ-cyhalothrin, contributing to a better understanding of aphid resistance to pyrethroids.


Assuntos
Afídeos , Inseticidas , Nitrilas , Piretrinas , Animais , Simulação de Acoplamento Molecular
17.
Front Environ Sci Eng ; 16(6): 70, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34608423

RESUMO

The rapid global spread of coronavirus disease 2019 (COVID-19) has promoted concern over human pathogens and their significant threats to public health security. The monitoring and control of human pathogens in public sanitation and health facilities are of great importance. Excessive sludge is an inevitable byproduct of sewage that contains human and animal feces in wastewater treatment plants (WWTPs). It is an important sink of different pollutants and pathogens, and the proper treatment and disposal of sludge are important to minimize potential risks to the environment and public health. However, there is a lack of comprehensive analysis of the diversity, exposure risks, assessment methods and inactivation techniques of pathogenic microorganisms in sludge. Based on this consideration, this review summarizes the control performance of pathogenic microorganisms such as enterovirus, Salmonella spp., and Escherichia coli by different sludge treatment technologies, including composting, anaerobic digestion, aerobic digestion, and microwave irradiation, and the mechanisms of pathogenic microorganism inactivation in sludge treatment processes are discussed. Additionally, this study reviews the diversity, detection methods, and exposure risks of pathogenic microorganisms in sludge. This review advances the quantitative assessment of pathogenic microorganism risks involved in sludge reuse and is practically valuable to optimize the treatment and disposal of sludge for pathogenic microorganism control.

18.
Rev Sci Instrum ; 93(12): 125101, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586951

RESUMO

The shape of the salt cavern is very important for the safe operation of gas storage facilities in rock salt. A physical simulation test is an effective means to study the shape control of salt caverns. To accurately simulate the process and parameters of single-well solution mining in rock salt, we developed simulation technologies and a testing system for cavern shape control. Based on the flow similarity principle, we established a sealing technology for dynamic-static disturbance and successfully replicated the solution mining process for forward and reverse circulations. Based on the requirement of protective fluid in the field, we developed a protection liquid unit to control the oil pad height to avoid overdissolution or uneven dissolution at the top of the salt cavern. From the principle of distance determination by laser and video, we developed a salt cavern shape visualization and micro-distance detection system that can realize the size measurement and real-time visualization of the salt cavern in pressurized corrosive environment. We put forward the control technology of the testing system that can achieve the integrated and collaborative control of inner and outer pipe spacing, water flow during injection-production circulations, and the height of protection fluid. Finally, we carried out a physical simulation test of solution mining for cavern shape control. The shape and size of the salt cavern from the test are in good agreement with the design. This study can provide an important basis for determining the optimal solution in mining technology and the parameters for cavern shape control.

19.
J Hazard Mater ; 426: 128001, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34933261

RESUMO

The dissemination of antibiotic resistance genes (ARGs) increases risks towards human health and environmental safety. This work investigates the control of ARGs abundance and bacterial community evolution involved in waste activated sludge (WAS) treatment by chemical conditioning and subsequent mesophilic anaerobic digestion (MAD). The different chemical oxidation processes of ferrous iron-activated oxone and hydrogen peroxide (PMS-Fe2+ and H2O2-Fe2+) and thermal-activated oxone (PMS@80 â„ƒ) were investigated, and the ferric chloride (FeCl3) and inactivated oxone (PMS) were compared. PMS@80 â„ƒ decreased the absolute abundance of most ARGs by 10.6-99.3% and that of total ARGs by 66.3%. Interestingly, oxidation pretreatment increased rather than decreased the relative abundance of most ARGs. MAD with PMS@80 â„ƒ pretreatment increased the absolute abundance of total ARGs by 51.6%, and other MAD processes decreased it by 8.6-47.4%. PMS-Fe2+ and PMS@80 â„ƒ negatively inhibited methane production from 98.3 to 81.7 and 94.4 mL/g VSS in MAD. MAD effluent showed high abundance of Arcobacter genus in the range of 8.1-17.4% upon PMS-based pretreatment, possibly related to sulfur oxidation, nitrate reduction, and blaVEB enrichment. The radicals-orientated chemical oxidation can hardly improve the ARGs elimination by MAD due to the extremely high competitive organics in sludge.


Assuntos
Antibacterianos , Esgotos , Anaerobiose , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos , Peróxido de Hidrogênio
20.
Anal Chim Acta ; 1163: 338502, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34024418

RESUMO

A tungsten coil (W-coil) as an electrothermal vaporizer (ETV) was interface-free integrated with a point discharge (PD) microplasma as an excitation source for a miniaturized optical emission spectrometer (OES). The PD microplasma and the W-coil ETV were vertically arranged in one quartz tube, and the W-coil was directly placed just under the PD without any physical interface. Working gas flow could sweep them successively to carry analytes released from the W-coil to the PD microplasma, and exhaust out of the quartz tube. The W-coil firstly acted as an ETV for sampling, on which pipetted with a tiny amount of sample solution (typically 10 µL), followed by a heating program for eliminating sample moisture and matrix. Vapor of analytes was subsequently released from the W-coil at a high temperature and immediately swept into the PD microplasma for excitation of atoms to obtain their optical emission spectra. Due to the high temperature of the W-coil, the released analyte species from the W-coil probably had been already atomized/excited partly and partially maintained prior to entering into the PD microplasma, thus saving the energy in the PD for sample evaporation and dissociation. In other words, the W-coil indirectly provided extra energy to the PD microplasma, thus its excitation capability was intensified. Under optimal experimental conditions, simultaneous determination of Ag, As, Bi, Cd, Cu, In, Pb, Sb and Zn was achieved, with LODs of 0.6, 45, 40, 0.08, 15, 8, 8, 41 and 5 µg L-1, respectively, and RSDs all less than 4.5% (n = 3, at corresponding concentrations of 5, 250, 250, 0.5, 100, 50, 50, 250 and 25 µg L-1). The accuracy validation of the proposed technique was demonstrated by successfully analyzing Certified Reference Materials (CRMs, including water, soil, stream sediment and biological samples), and preliminarily analyzing one CRM with direct slurry injection, both with satisfactory results, which had no significant difference with the certificated values at a confidence level of 95% by t-test.

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