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ETHNOPHARMACOLOGICAL RELEVANCE: Zhubi Decoction (ZBD) is a modified formulation derived from the classic traditional Chinese medicine prescription "Er-Xian Decoction" documented in the esteemed "Clinical Manual of Chinese Medical Prescription". While the utilization of ZBD has exhibited promising clinical outcomes in treating rheumatoid arthritis (RA), the precise bioactive chemical constituents and the underlying mechanisms involved in its therapeutic efficacy remain to be comprehensively determined. AIM OF THE STUDY: This study aims to systematically examine ZBD's pharmacological effects and molecular mechanisms for RA alleviation. MATERIALS AND METHODS: Utilizing the collagen-induced arthritis (CIA) rat model, we comprehensively evaluated the anti-rheumatoid arthritis effects of ZBD in vivo through various indices, such as paw edema, arthritis index, ankle diameter, inflammatory cytokine levels, pathological conditions, and micro-CT analysis. The UPLC-MS/MS technique was utilized to analyze the compounds of ZBD. The potential therapeutic targets and signaling pathways of ZBD in the management of RA were predicted using network pharmacology. To analyze comprehensive metabolic profiles and identify underlying metabolic pathways, we conducted a serum-based widely targeted metabolomics analysis utilizing LC-MS technology. Key targets and predicted pathways were further validated using immunofluorescent staining, which integrated findings from serum metabolomics and network pharmacology analysis. Additionally, we analyzed the gut microbiota composition in rats employing 16 S rDNA sequencing and investigated the effects of ZBD on the microbiota of CIA rats through bioinformatics and statistical methods. RESULTS: ZBD exhibited remarkable efficacy in alleviating RA symptoms in CIA rats without notable side effects. This included reduced paw redness and swelling, minimized joint damage, improved the histopathology of cartilage and synovium, mitigated the inflammatory state, and lowered serum concentrations of cytokines TNF-α, IL-1ß and IL-6. Notably, the effectiveness of ZBD was comparable to MTX. Network pharmacology analysis revealed inflammation and immunity-related signaling pathways, such as PI3K/AKT, MAPK, IL-17, and TNF signaling pathways, as vital mediators in the effectual mechanisms of ZBD. Immunofluorescence analysis validated ZBD's ability to inhibit PI3K/AKT pathway proteins. Serum metabolomics studies revealed that ZBD modulates 170 differential metabolites, partially restored disrupted metabolic profiles in CIA rats. With a notable impact on amino acids and their metabolites, and lipids and lipid-like molecules. Integrated analysis of metabolomics and network pharmacology identified 6 pivotal metabolite pathways and 3 crucial targets: PTGS2, GSTP1, and ALDH2. Additionally, 16 S rDNA sequencing illuminated that ZBD mitigated gut microbiota dysbiosis in the CIA group, highlighting key genera such as Ligilactobacillus, Prevotella_9, unclassified_Bacilli, and unclassified_rumen_bacterium_JW32. Correlation analysis disclosed a significant link between 47 distinct metabolites and specific bacterial species. CONCLUSION: ZBD is a safe and efficacious TCM formulation, demonstrates efficacy in treating RA through its multi-component, multi-target, and multi-pathway mechanisms. The regulation of inflammation and immunity-related signaling pathways constitutes a crucial mechanism of ZBD's efficacy. Furthermore, ZBD modulates host metabolism and intestinal flora. The integrated analysis presents experimental evidence of ZBD for the management of RA.
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Artrite Experimental , Artrite Reumatoide , Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Metabolômica , Farmacologia em Rede , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Masculino , Ratos , Antirreumáticos/farmacologia , Antirreumáticos/uso terapêutico , Citocinas/sangue , Citocinas/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Conventional diffusion-weighted imaging (DWI) sequences employing a spin echo or stimulated echo sensitize diffusion with a specific b-value at a fixed diffusion direction and diffusion time (Δ). To compute apparent diffusion coefficient (ADC) and other diffusion parameters, the sequence needs to be repeated multiple times by varying the b-value and/or gradient direction. In this study, we developed a single-shot multi-b-value (SSMb) diffusion MRI technique, which combines a spin echo and a train of stimulated echoes produced with variable flip angles. The method involves a pair of 90° radio frequency (RF) pulses that straddle a diffusion gradient lobe (GD), to rephase the magnetization in the transverse plane, producing a diffusion-weighted spin echo acquired by the first echo-planar imaging (EPI) readout train. The magnetization stored along the longitudinal axis is successively re-excited by a series of n variable-flip-angle pulses, each followed by a diffusion gradient lobe GD and a subsequent EPI readout train to sample n stimulated-echo signals. As such, (n + 1) diffusion-weighted images, each with a distinct b-value, are acquired in a single shot. The SSMb sequence was demonstrated on a diffusion phantom and healthy human brain to produce diffusion-weighted images, which were quantitative analyzed using a mono-exponential model. In the phantom experiment, SSMb provided similar ADC values to those from a commercial spin-echo EPI (SE-EPI) sequence (r = 0.999). In the human brain experiment, SSMb enabled a fourfold scan time reduction and yielded slightly lower ADC values (0.83 ± 0.26 µm2/ms) than SE-EPI (0.88 ± 0.29 µm2/ms) in all voxels excluding cerebrospinal fluid, likely due to the influence of varying diffusion times. The feasibility of using SSMb to acquire multiple images in a single shot for intravoxel incoherent motion (IVIM) analysis was also demonstrated. In conclusion, despite a relatively low signal-to-noise ratio, the proposed SSMb technique can substantially increase the data acquisition efficiency in DWI studies.
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Dengue, an acute febrile disease transmitted by Aedes mosquitoes, is caused by the dengue virus (DENV), presenting a formidable challenge to global public health. By examining clues from ancient Chinese books and conducting a comprehensive review, this study elucidates the characteristics of potential dengue epidemics in China prior to 1978. This evidence indicates that China may not have experience dengue epidemics before 1840. During 1840-1949, however, it experienced a noticeable dengue occurrence and prevalence in the 1870s, 1920s, and 1940s. Then from 1949 to 1978, only sporadic reports were accounted. The disparity in the frequency of dengue occurrences across three time periods suggests that the persistent characteristic of dengue epidemics in China primarily arises from imported cases resulting from international exchanges, subsequently leading to local outbreaks influenced by global epidemic trend. This research offers a novel perspective on retrospectively examining the historical trajectory of dengue epidemics and provides valuable insights into exploration of DENV epidemic patterns.
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Dengue , Epidemias , Dengue/epidemiologia , Dengue/história , China/epidemiologia , Humanos , História do Século XX , Epidemias/história , História do Século XIX , Vírus da Dengue , Animais , Aedes/virologiaRESUMO
Long terminal repeat retroelements (LTR-REs) have profound effects on DNA methylation and gene regulation. Despite the vast abundance of LTR-REs in the genome of Moso bamboo (Phyllostachys edulis), an industrial crop in underdeveloped countries, their precise implication of the LTR-RE mobility in stress response and development remains unknown. We investigated the RNA and DNA products of LTR-REs in Moso bamboo under various developmental stages and stressful conditions. Surprisingly, our analyses identified thousands of active LTR-REs, particularly those located near genes involved in stress response and developmental regulation. These genes adjacent to active LTR-REs exhibited an increased expression under stress and are associated with reduced DNA methylation that is likely affected by the induced LTR-REs. Moreover, the analyses of simultaneous mapping of insertions and DNA methylation showed that the LTR-REs effectively alter the epigenetic status of the genomic regions where they inserted, and concomitantly their transcriptional competence which might impact the stress resilience and growth of the host. Our work unveils the unusually strong LTR-RE mobility in Moso bamboo and its close association with (epi)genetic changes, which supports the co-evolution of the parasitic DNAs and host genome in attaining stress tolerance and developmental robustness.
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Fentanyl combined with bupivacaine in subarachnoid anesthesia exerts a strong synergistic analgesic effect, extending the duration of analgesia. However, the mechanism of enhanced analgesic effect of fentanyl remains elusive. The present study investigated the potential mechanism of the analgesic effect of fentanyl when combined with bupivacaine. The subarachnoid injection (SI) rat model was employed, and SI of fentanyl or/and bupivacaine was used to investigate their analgesic effect. Dorsal root ganglion (DRG)' RNA sequencing (RNA-Seq) and bioinformatics analysis were performed to evaluate the downstream mechanisms of MicroRNAs (miRNAs). Further validation tests included RT-PCR, Western blot, and immunofluorescence. A single SI of fentanyl or bupivacaine decreased the positive responses to stimulation when used alone or in combination. RNA-seq results revealed that miR-381-3p played a role in the fentanyl-driven promotion of analgesia. Bioinformatics analysis and dual-luciferase reporter identified TRPM7 as a direct downstream target gene of miR-381-3p. In vitro, overexpression of miR-381-3p could further block fentanyl-induced expression of TRPM7, p-ERK1/2, CGRP, and SP. In addition, antagomir-381-3p reversed the inhibitory effect of fentanyl on the expression of TRPM7, p-ERK1/2, CGRP, and SP, in vivo; however, TRPM7 siRNA rescued the effect of antagomir-381-3p. In conclusion, fentanyl inhibits p-ERK by targeting TRPM7 via miR-381-3p, lowering the production of CGRP and SP, and ultimately inducing analgesic effects.
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Bupivacaína , Fentanila , Gânglios Espinais , MicroRNAs , Canais de Cátion TRPM , Animais , Masculino , Ratos , Analgésicos/administração & dosagem , Analgésicos/farmacologia , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/farmacologia , Anestésicos Locais/farmacologia , Anestésicos Locais/administração & dosagem , Bupivacaína/administração & dosagem , Bupivacaína/farmacologia , Sinergismo Farmacológico , Fentanila/administração & dosagem , Fentanila/farmacologia , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Injeções Espinhais , MicroRNAs/genética , Ratos Sprague-Dawley , Canais de Cátion TRPM/genéticaRESUMO
We investigate the mechanism of action of astragalin (AST) in the treatment of Alzheimer's disease (AD). Network pharmacology was conducted to analyze the relationships among AST, AD, and neuroinflammation, The APP/PS1 transgenic mice with AD were used in the experiments; to be specific, the influence of AST on the behavior of mice was analyzed by Morris water maze and eight-arm radial maze tests, the tissue inflammatory factor levels were detected by ELISA, and pathological changes were analyzed by H&E and immunohistochemical staining. Analysis results of network pharmacology suggested that AST exerted the multi-target effect on neuroinflammation in AD. Through molecular docking and dynamics analyses, COX2 might be the target of AST. Moreover, animal experimental results demonstrated that AST improved the behavior of AD mice, and enhanced the motor and memory abilities, meanwhile, it suppressed the expression of inflammatory factors in tissues and the activation of microglial cells. this study discovers that AST can suppress microglial cell activation via COX2 to improve neuroinflammation in AD.
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Doença de Alzheimer , Quempferóis , Camundongos Transgênicos , Simulação de Acoplamento Molecular , Farmacologia em Rede , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Camundongos , Quempferóis/farmacologia , Quempferóis/uso terapêutico , Aprendizagem em Labirinto/efeitos dos fármacos , Masculino , Ciclo-Oxigenase 2/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismoRESUMO
BACKGROUND: This study aimed to determine the effect and mechanism of the Decoction of Yougui Wan combined with Wuzi Yanzong Wan (DYWWYW), a traditional Chinese herbal formula, in a mouse model with thin endometrium induced by 95% ethanol. METHODS: Thin endometrium mice were treated with progynova (0.002 mg) as well as a low and high dose of DYWWYW (0.05 and 0.5 mL DYWWYW, respectively, diluted in 2 mL normal saline). Western blotting and qRT-PCR analyses were performed to determine the protein and mRNA expression levels, respectively, of integrin αγß3 and leukaemia inhibitor factor (LIF) in uterus tissues. Serum oestradiol and progesterone concentrations were determined via ELISA. The remaining thin endometrium mice were mated with male mice, and the number of embryos implanted in the different groups was calculated. RESULTS: A high dose of DYWWYW effectively ameliorated the injury of endometrium caused by 95% ethanol. The levels of oestradiol, progesterone, αγß3 and LIF in thin endometrium mice treated with a high dose of DYWWYW were also significantly elevated. Additionally, a high dose of DYWWYW remarkably increased the number of embryo implantations in mice with thin endometrium. CONCLUSION: DYWWYW has improvement effects on thin endometrium by elevating the levels of endogenous oestradiol, progesterone, αγß3, and LIF in a mouse model.
During the reproductive cycle, endometrium thickness of more than 7 mm is considered as a cut-off value for successful embryo implantation. Currently, although therapies for the improvement of endometrium thickness such as sildenafil, endometrial scraping, granulocyte colony-stimulating factor and low dose of aspirin have been tried, the effects on patients are not consistent. Consequently, it is necessary to seek novel therapies to increase endometrium thickness effectively. A 95% ethanol-induced thin endometrium female ICR mouse model was established in this study. High dose of Decoction of Yougui Wan combined with Wuzi Yanzong Wan (DYWWYW) effectively ameliorated the injury of endometrium and remarkably increased the number of embryo implantations in thin endometrium mice. Additionally, the levels of some key indicators including oestradiol, progesterone, αγß3, and LIF were also increased in thin endometrium mice treated with high dose of DYWWYW. Therefore, DYWWYW was feasible in increasing endometrium thickness in a mouse model.
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Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Endométrio , Estradiol , Fator Inibidor de Leucemia , Progesterona , Animais , Feminino , Medicamentos de Ervas Chinesas/farmacologia , Camundongos , Endométrio/efeitos dos fármacos , Endométrio/metabolismo , Estradiol/sangue , Progesterona/sangue , Fator Inibidor de Leucemia/metabolismo , Etanol , Masculino , Doenças Uterinas/tratamento farmacológicoRESUMO
Severe acute respiratory syndrome coronaviruses 2 (SARS-CoV-2) causing coronavirus disease 2019 (COVID-19) affected the health of human beings and the global economy. The patients with SARS-CoV-2 infection had viral RNA or live infectious viruses in feces. Thus, the possible transmission of SARS-CoV-2 through wastewater received great attentions. Moreover, SARS-CoV-2 in wastewater can serve as an early indicator of the infection within communities. We summarized the preconcentration and detection technology of SARS-CoV-2 in wastewater aiming at the complex matrices of wastewater and low virus concentration and compared their performance characteristics. We described the emerging tests that would be possible to realize the rapid detection of SARS-CoV-2 in fields and encourage academics to advance their technologies beyond conception. We concluded with a brief discussion on the outlook for integrating preconcentration and the detection of SARS-CoV-2 with emerging technologies.
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Técnicas Biossensoriais , COVID-19 , SARS-CoV-2 , Águas Residuárias , Águas Residuárias/virologia , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/genética , COVID-19/virologia , COVID-19/diagnóstico , COVID-19/transmissão , Humanos , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , RNA Viral/análise , RNA Viral/isolamento & purificaçãoRESUMO
Immunotherapy combined with chemotherapy regimen has been shown to be effective in recurrent or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC). However, due to the small number of patients, its efficacy remains controversial in Asian populations, particularly in mainland China. Here a randomized, double-blind phase 3 trial evaluated the efficacy and safety of finotonlimab (SCT-I10A), a programmed cell death 1 (PD-1) monoclonal antibody, combined with cisplatin plus 5-fluorouracil (C5F) for the first-line treatment of R/M HNSCC. Eligible patients (n = 370) were randomly 2:1 assigned to receive finotonlimab plus C5F (n = 247) or placebo plus C5F (n = 123). The primary endpoint was overall survival (OS). In the finotonlimab plus C5F group, OS was 14.1 months (95% confidence interval (CI) 11.1-16.4), compared with 10.5 months (95% CI 8.1-11.8) in the placebo plus C5F group. The hazard ratio was 0.73 (95% CI 0.57-0.95, P = 0.0165), meeting the predefined superiority criteria for the primary endpoint. Finotonlimab plus C5F showed significant OS superiority compared with C5F alone and acceptable safety profile with R/M HNSCC, supporting its use as a first-line treatment option for R/M HNSCC. These results validate the efficacy and safety of the combination of finotonlimab and C5F in Asian patients with R/M HNSCC. ClinicalTrials.gov identifier: NCT04146402 .
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Protocolos de Quimioterapia Combinada Antineoplásica , Cisplatino , Neoplasias de Cabeça e Pescoço , Recidiva Local de Neoplasia , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Idoso , Adulto , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Método Duplo-Cego , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Metástase NeoplásicaRESUMO
PURPOSE: To develop and demonstrate a fast 3D fMRI acquisition technique with high spatial resolution over a reduced FOV, named k-t 3D reduced FOV imaging (3D-rFOVI). METHODS: Based on 3D gradient-echo EPI, k-t 3D-rFOVI used a 2D RF pulse to reduce the FOV in the in-plane phase-encoding direction, boosting spatial resolution without increasing echo train length. For image acceleration, full sampling was applied in the central k-space region along the through-slab direction (kz) for all time frames, while randomized undersampling was used in outer kz regions at different time frames. Images were acquired at 3T and reconstructed using a method based on partial separability. fMRI detection sensitivity of k-t 3D-rFOVI was quantitively analyzed with simulation data. Human visual fMRI experiments were performed to evaluate k-t 3D-rFOVI and compare it with a commercial multiband EPI sequence. RESULTS: The simulation data showed that k-t 3D-rFOVI can detect 100% of fMRI activations with an acceleration factor (R) of 2 and Ë80% with R = 6. In the human fMRI data acquired with 1.5-mm spatial resolution and 800-ms volume TR (TRvol), k-t 3D-rFOVI with R = 4 detected 46% more activated voxels in the visual cortex than the multiband EPI. Additional fMRI experiments showed that k-t 3D-rFOVI can achieve TRvol of 480 ms with R = 6, while reliably detecting visual activation. CONCLUSIONS: k-t 3D-rFOVI can simultaneously achieve a high spatial resolution (1.5-mm isotropically) and short TRvol (480-ms) at 3T. It offers a robust acquisition technique for fast fMRI studies over a focused brain volume.
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Algoritmos , Encéfalo , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Adulto , Processamento de Imagem Assistida por Computador/métodos , Imagem Ecoplanar/métodos , Simulação por Computador , Masculino , FemininoRESUMO
The Gag-Pol polyprotein in human immunodeficiency virus type I (HIV-1) encodes enzymes that are essential for virus replication: protease (PR), reverse transcriptase (RT), and integrase (IN). The mature forms of PR, RT and IN are homodimer, heterodimer and tetramer, respectively. The precise mechanism underlying the formation of dimer or tetramer is not yet understood. Here, to gain insight into the dimerization of PR and RT in the precursor, we prepared a model precursor, PR-RT, incorporating an inactivating mutation at the PR active site, D25A, and including two residues in the p6* region, fused to a SUMO-tag, at the N-terminus of the PR region. We also prepared two mutants of PR-RT containing a dimer dissociation mutation either in the PR region, PR(T26A)-RT, or in the RT region, PR-RT(W401A). Size exclusion chromatography showed both monomer and dimer fractions in PR-RT and PR(T26A)-RT, but only monomer in PR-RT(W401A). SEC experiments of PR-RT in the presence of protease inhibitor, darunavir, significantly enhanced the dimerization. Additionally, SEC results suggest an estimated PR-RT dimer dissociation constant that is higher than that of the mature RT heterodimer, p66/p51, but slightly lower than the premature RT homodimer, p66/p66. Reverse transcriptase assays and RT maturation assays were performed as tools to assess the effects of the PR dimer-interface on these functions. Our results consistently indicate that the RT dimer-interface plays a crucial role in the dimerization in PR-RT, whereas the PR dimer-interface has a lesser role.
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Protease de HIV , Transcriptase Reversa do HIV , HIV-1 , Multimerização Proteica , Transcriptase Reversa do HIV/química , Transcriptase Reversa do HIV/metabolismo , Transcriptase Reversa do HIV/genética , Protease de HIV/química , Protease de HIV/genética , Protease de HIV/metabolismo , HIV-1/enzimologia , HIV-1/genética , HIV-1/química , Humanos , Modelos Moleculares , DimerizaçãoRESUMO
Background: Emerging infectious diseases pose a significant threat to global public health. Timely detection and response are crucial in mitigating the spread of such epidemics. Inferring the onset time and epidemiological characteristics is vital for accelerating early interventions, but accurately predicting these parameters in the early stages remains challenging. Methods: We introduce a Bayesian inference method to fit epidemic models to time series data based on state-space modeling, employing a stochastic Susceptible-Exposed-Infectious-Removed (SEIR) model for transmission dynamics analysis. Our approach uses the particle Markov chain Monte Carlo (PMCMC) method to estimate key epidemiological parameters, including the onset time, the transmission rate, and the recovery rate. The PMCMC algorithm integrates the advantageous aspects of both MCMC and particle filtering methodologies to yield a computationally feasible and effective means of approximating the likelihood function, especially when it is computationally intractable. Results: To validate the proposed method, we conduct case studies on COVID-19 outbreaks in Wuhan, Shanghai and Nanjing, China, respectively. Using early-stage case reports, the PMCMC algorithm accurately predicted the onset time, key epidemiological parameters, and the basic reproduction number. These findings are consistent with empirical studies and the literature. Conclusion: This study presents a robust Bayesian inference method for the timely investigation of emerging infectious diseases. By accurately estimating the onset time and essential epidemiological parameters, our approach is versatile and efficient, extending its utility beyond COVID-19.
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Algoritmos , Teorema de Bayes , COVID-19 , Doenças Transmissíveis Emergentes , Cadeias de Markov , Humanos , Doenças Transmissíveis Emergentes/epidemiologia , COVID-19/epidemiologia , COVID-19/transmissão , China/epidemiologia , Método de Monte Carlo , SARS-CoV-2 , Surtos de Doenças/estatística & dados numéricos , Fatores de Tempo , Modelos EpidemiológicosRESUMO
Introduction: Aspergillus cristatus is a homothallic fungus that is used in the natural fermentation process of Chinese Fuzhuan tea and has been linked to the production of bioactive components. However, not much is known about the variations present in the fungus. To understand the variation of the dominant microorganism, A. cristatus, within dark tea, the present study investigated the genetic and morphological diversity of 70 A. cristatus collected across six provinces of China. Methods: Expressed sequence tags-simple sequence repeats (EST-SSR) loci for A. cristatus were identified and corresponding primers were developed. Subsequently, 15 specimens were selected for PCR amplification. Results: The phylogenetic tree obtained revealed four distinct clusters with a genetic similarity coefficient of 0.983, corresponding to previously identified morphological groups. Five strains (A1, A11, B1, D1, and JH1805) with considerable differences in EST-SSR results were selected for further physiological variation investigation. Microstructural examinations revealed no apparent differentiation among the representative strains. However, colony morphology under a range of culture media varied substantially between strains, as did the extracellular enzymatic activity (cellulase, pectinase, protease, and polyphenol oxidase); the data indicate that there are differences in physiological metabolic capacity among A. cristatus strains. Discussion: Notably, JH1805, B1, and A11 exhibited higher enzymatic activity, indicating their potential application in the production of genetically improved strains. The findings provide valuable insights into species identification, genetic diversity determination, and marker-assisted breeding strategies for A. cristatus.
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BACKGROUND: The strong invasiveness and rapid expansion of dengue virus (DENV) pose a great challenge to global public health. However, dengue epidemic patterns and mechanisms at a genetic scale, particularly in term of cross-border transmissions, remain poorly understood. Importation is considered as the primary driver of dengue outbreaks in China, and since 1990 a frequent occurrence of large outbreaks has been triggered by the imported cases and subsequently spread to the western and northern parts of China. Therefore, this study aims to systematically reveal the invasion and diffusion patterns of DENV-1 in Guangdong, China from 1990 to 2019. METHODS: These analyses were performed on 179 newly assembled genomes from indigenous dengue cases in Guangdong, China and 5152 E gene complete sequences recorded in Chinese mainland. The genetic population structure and epidemic patterns of DENV-1 circulating in Chinese mainland were characterized by phylogenetics, phylogeography, phylodynamics based on DENV-1 E-gene-based globally unified genotyping framework. RESULTS: Multiple serotypes of DENV were co-circulating in Chinese mainland, particularly in Guangdong and Yunnan provinces. A total of 189 transmission clusters in 38 clades belonging to 22 subgenotypes of genotype I, IV and V of DENV-1 were identified, with 7 Clades of Concern (COCs) responsible for the large outbreaks since 1990. The epidemic periodicity was inferred from the data to be approximately 3 years. Dengue transmission events mainly occurred from Great Mekong Subregion-China (GMS-China), Southeast Asia (SEA), South Asia Subcontinent (SASC), and Oceania (OCE) to coastal and land border cities respectively in southeastern and southwestern China. Specially, Guangzhou was found to be the most dominant receipting hub, where DENV-1 diffused to other cities within the province and even other parts of the country. Genome phylogeny combined with epidemiological investigation demonstrated a clear local consecutive transmission process of a 5C1 transmission cluster (5C1-CN4) of DENV-1 in Guangzhou from 2013 to 2015, while the two provinces of Guangdong and Yunnan played key roles in ongoing transition of dengue epidemic patterns. In contextualizing within Invasion Biology theories, we have proposed a derived three-stage model encompassing the stages of invasion, colonization, and dissemination, which is supposed to enhance our understanding of dengue spreading patterns. CONCLUSIONS: This study demonstrates the invasion and diffusion process of DENV-1 in Chinese mainland within a global genotyping framework, characterizing the genetic diversities of viral populations, multiple sources of importation, and periodic dynamics of the epidemic. These findings highlight the potential ongoing transition trends from epidemic to endemic status offering a valuable insight into early warning, prevention and control of rapid spreading of dengue both in China and worldwide.
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Vírus da Dengue , Dengue , Genótipo , Filogenia , Sorogrupo , Vírus da Dengue/genética , Vírus da Dengue/classificação , Vírus da Dengue/fisiologia , China/epidemiologia , Dengue/epidemiologia , Dengue/virologia , Dengue/transmissão , Humanos , Surtos de Doenças , Filogeografia , Genoma ViralRESUMO
Shallow lakes, recognized as hotspots for nitrogen cycling, contribute to the emission of the potent greenhouse gas nitrous oxide (N2O), but the current emission estimates for this gas have a high degree of uncertainty. However, the role of N2O-reducing bacteria (N2ORB) as N2O sinks and their contribution to N2O reduction in aquatic ecosystems in response to N2O dynamics have not been determined. Here, we investigated the N2O dynamics and microbial processes in the nitrogen cycle, which included both N2O production and consumption, in five shallow lakes spanning approximately 500 km. The investigated sites exhibited N2O oversaturation, with excess dissolved N2O concentrations (ΔN2O) ranging from 0.55 ± 0.61 to 53.17 ± 15.75 nM. Sediment-bound N2O (sN2O) was significantly positively correlated with the nitrate concentration in the overlying water (p < 0.05), suggesting that nitrate accumulation contributes to benthic N2O generation. High N2O consumption activity (RN2O) corresponded to low ΔN2O. In addition, a significant negative correlation was found between RN2O and nir/nosZ, showing that bacteria encoding nosZ contributed to N2O consumption in the benthic sediments. Redundancy analysis indicated that benthic functional genes effectively reflected the variations in RN2O and ∆N2O. qPCR analysis revealed that the clade II nosZ gene was more sensitive to ΔN2O than the clade I nosZ gene. Furthermore, four novel genera of potential nondenitrifying N2ORB were identified based on metagenome-assembled genome analysis. These genera, which are affiliated with clade II, lack genes responsible for N2O production. Collectively, benthic N2ORB, especially for clade II-type N2ORB, harnesses N2O consumption activity leading to low N2O emissions from shallow lakes. This study advances our knowledge of the role of benthic clade II-type N2ORB in regulating N2O emissions in shallow lakes.
Assuntos
Bactérias , Lagos , Óxido Nitroso , Óxido Nitroso/análise , Lagos/química , Bactérias/classificação , Monitoramento Ambiental , Ciclo do Nitrogênio , Poluentes Atmosféricos/análise , Sedimentos Geológicos/químicaRESUMO
As an emerging pollutant, microplastics (MPs) cause widespread concern around the world owing to the serious threat they pose to ecosystems. In particular, sediments are thought to be the long-term sink for the continual accumulation of MPs in freshwater ecosystems. Polyethylene (PE) and polyethylene terephthalate (PET) have been frequently detected with large concentration variations in freshwater sediments from the lower reaches of the Yangtze River, one of the most economically developed regions in China, characterized by accelerated urbanization and industrialization, high population density and high plastics consumption. However, the impact of PE and PET on the sedimental bacterial community composition and its function has not been well reported for this specific region. Herein, PE and PET particles were added to freshwater sediments to assess the effects of different MP types on the bacterial community and its function, using three concentrations (500, 1500 and 2500 items/kg) per MP and incubations of 35, 105 and 175 days, respectively. This study identified a total of 68 phyla, 211 classes, 518 orders, 853 families and 1745 genera. Specifically, Proteobacteria, Chloroflexi, Acidobacteriota, Actinobacteriota and Firmicutes were the top five phyla. A higher bacterial diversity was obtained in control sediments than in the MP-treated sediments. The presence of MPs, whether PET or PE, had significant impact on the bacterial diversity, community structure and community composition. PICRUSt2 and FAPOTAX predictions demonstrated that MPs could potentially affect the metabolic pathways and ecologically functional groups of bacteria in the sediment. Besides the MP-related factors, such as the type, concentration and incubation time, the physicochemical parameters had an effect on the structure and function of the bacterial community in the freshwater sediment. Taken together, this study provides useful information for further understanding how MPs affect bacterial communities in the freshwater sediment of the lower reaches of the Yangtze River, China.
Assuntos
Bactérias , Sedimentos Geológicos , Lagos , Microplásticos , Poluentes Químicos da Água , Microplásticos/toxicidade , Microplásticos/análise , Sedimentos Geológicos/microbiologia , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Bactérias/classificação , Bactérias/efeitos dos fármacos , China , Lagos/microbiologia , Lagos/química , Polietilenotereftalatos , Monitoramento Ambiental , Polietileno , Ecossistema , Água Doce/microbiologia , Água Doce/químicaRESUMO
There is increasing global concern regarding the pervasive issue of plastic pollution. We investigated the response of Populus × euramericana cv. '74/76' to nanoplastic toxicity via phenotypic, microanatomical, physiological, transcriptomic, and metabolomic approaches. Polystyrene nanoplastics (PS-NPs) were distributed throughout the test plants after the application of PS-NPs. Nanoplastics principally accumulated in the roots; minimal fractions were translocated to the leaves. In leaves, however, PS-NPs easily penetrated membranes and became concentrated in chloroplasts, causing thylakoid disintegration and chlorophyll degradation. Finally, oxidant damage from the influx of PS-NPs led to diminished photosynthesis, stunted growth, and etiolation and/or wilting. By integrating dual-omics data, we found that plants could counteract mild PS-NP-induced oxidative stress through the antioxidant enzyme system without initiating secondary metabolic defense mechanisms. In contrast, severe PS-NP treatments promoted a shift in metabolic pattern from primary metabolism to secondary metabolic defense mechanisms, an effect that was particularly pronounced during the upregulation of flavonoid biosynthesis. Our findings provide a useful framework from which to further clarify the roles of key biochemical pathways in plant responses to nanoplastic toxicity. Our work also supports the development of effective strategies to mitigate the environmental risks of nanoplastics by biologically immobilizing them in contaminated lands.