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1.
J Geriatr Cardiol ; 21(5): 542-549, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38948892

RESUMO

BACKGROUND: The neutrophil to lymphocyte ratio (NLR) has been reported as a novel predictor for atherosclerosis and cardiovascular outcomes. This study aimed to determine the effects of NLR on long-term clinical outcomes of chronic total occlusion (CTO) patients. METHODS: A total of 670 patients with CTO who met the inclusion criteria were included at the end of the follow-up period. Patients were divided into tertiles according to their baseline NLR levels at admission: low (n = 223), intermediate (n = 223), and high (n = 224). The incidence of major adverse cardiac events (MACEs) during the follow-up period, including all-cause death, nonfatal myocardial infarction (MI), or ischemia-driven revascularization, were compared among the three groups. RESULTS: Major adverse cardiac events were observed in 27 patients (12.1%) in the low tertile, 40 (17.9%) in the intermediate tertile, and 61 (27.2%) in the high NLR tertile (P < 0.001). Kaplan-Meier analysis demonstrated a significantly higher incidence of MACE, ischemia-driven coronary revascularization, non-fatal MI, and mortality in patients within the high tertile than those in the low and intermediate groups (all P < 0.001). Multivariable COX regression analysis showed that the high tertile of baseline NLR level showed a strong association with the risk of MACE (hazard ratio [HR] = 2.21; 95% confidence interval [CI]: 1.21-4.03; P = 0.009), ischemia-driven coronary revascularization (HR = 3.19; 95% CI: 1.56-6.52; P = 0.001), MI (HR = 2.61; 95% CI: 1.35-5.03; P = 0.043) and mortality (HR = 3.78; 95% CI: 1.65-8.77; P = 0.001). CONCLUSION: Our findings suggest that NLR is an inexpensive and readily available biomarker that can independently predict cardiovascular risk in patients with CTO.

2.
J Med Virol ; 96(7): e29775, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38949184

RESUMO

Dengue fever is a mosquito-borne viral disease caused by the dengue virus (DENV). It poses a public health threat globally and, while most people with dengue have mild symptoms or are asymptomatic, approximately 5% of affected individuals develop severe disease and need hospital care. However, knowledge of the molecular mechanisms underlying dengue infection and the interaction between the virus and its host remains limited. In the present study, we performed a quantitative proteomic and N-glycoproteomic analysis of serum from 19 patients with dengue and 11 healthy people. The results revealed distinct proteomic and N-glycoproteomic landscapes between the two groups. Notably, we report for the first time the changes in the serum N glycosylation pattern following dengue infection and provide abundant information on glycoproteins, glycosylation sites, and intact N-glycopeptides using recently developed site-specific glycoproteomic approaches. Furthermore, a series of key functional pathways in proteomic and N-glycoproteomic were identified. Collectively, our findings significantly improve understanding of host and DENV interactions and the general pathogenesis and pathology of DENV, laying a foundation for functional studies of glycosylation and glycan structures in dengue infection.


Assuntos
Vírus da Dengue , Dengue , Glicoproteínas , Proteômica , Humanos , Dengue/sangue , Dengue/virologia , Proteômica/métodos , Glicoproteínas/sangue , Glicosilação , Masculino , Feminino , Adulto , Proteoma/análise , Pessoa de Meia-Idade
3.
Chem Commun (Camb) ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995155

RESUMO

A novel visible-light promoted metal-free radical cascade cyclization reaction has been developed with 3-allyl-2-arylquinazolinones as a new class of radical acceptor. This photocatalytic protocol represents an efficient approach to construct phosphorylated dihydroisoquinolino[1,2-b]quinazolinones featuring mild conditions, broad substrate scope, and gram-scale synthesis.

4.
Front Oncol ; 14: 1393414, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993646

RESUMO

Introduction: To assess the performance of the European Thyroid Association Thyroid Imaging and Reporting Data System (EU-TIRADS) and the Korean Thyroid Imaging Reporting and Data System (K-TIRADS), which combine risk stratification systems for thyroid nodules (TN-RSS) and cervical lymph nodes (LN-RSS) in diagnosing malignant and metastatic thyroid cancer in a single referral center. Methods: We retrospectively analyzed 2,055 consecutive patients who underwent thyroidectomy or fine-needle aspiration (FNA) from January 2021 to December 2022. TNs and LNs were categorized according to the ultrasonography (US) features of EU-TIRADS and K-TIRADS, respectively. The diagnostic performance and postponed malignancy rate (PMR) were compared with those of EU-TIRADS and K-TIRADS. PMR was defined as the number of patients with malignant nodules not recommended for biopsy among patients with cervical LN metastasis. Results: According to the EU-TIRADS and K-TIRADS, for TN-RSS alone, there were no significant differences in sensitivity, specificity, accuracy, unnecessary FNA rate (UFR), missed malignancy rate (MMR), and PMR between the two TIRADSs (29.0% vs. 28.8%, 50.5% vs. 51.1%, 32.3% vs. 32.2%, 23.6% vs. 23.5%, 88.6% vs. 88.5%, and 54.2% vs. 54.5%, P > 0.05 for all). Combining the LN-RSS increased the diagnostic accuracy (42.7% vs. 32.3% in EU-TIRADS; 38.8% vs. 32.2% in K-TIRADS) and decreased the PMR (54.2% vs. 33.9% in EU-TIRADS; 54.5% vs. 39.3% in K-TIRADS). EU-TIRADS had higher sensitivity and accuracy and lower PMR than K-TIRADS (41.3% vs. 36.7%, 42.7% vs. 38.8%,33.9% vs. 39.3%, P < 0.05 for all). Conclusions: A combination of TN-RSS and LN-RSS for the management of thyroid nodules may be associated with a reduction in PMR, with enhanced sensitivity and accuracy for thyroid cancers in EU-TIRADS and K-TIRADS. These results may offer a new direction for the detection of aggressive thyroid cancers.

5.
Comp Immunol Microbiol Infect Dis ; 111: 102214, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39002176

RESUMO

MicroRNAs (miRNAs) have been shown to play an important regulatory role in the process of pathogenic infection. However, the miRNAs that regulate the pathogenic process of G. parasuis and their functions are still unknown. Here, high-throughput sequencing was used to quantify the expression of miRNA in piglet lung tissue after G. parasuis XX0306 strain infection. A total of 25 differentially expressed microRNAs (DEmiRNAs) were identified. GO and KEGG pathway enrichment analysis showed that many of the functions of genes that may be regulated by DEmiRNA are related to inflammatory response and immune regulation. Further studies found that ssc-miR-135 may promote the expression of inflammatory factors through NF-κB signaling pathway. Whereas, ssc-miR-155-3p inhibited the inflammatory response induced by G. parasuis, and its regulatory mechanism remains to be further investigated. This study provides a valuable reference for revealing the regulatory effects of miRNAs on the pathogenesis of G. parasuis. DATA AVAILABILITY: The datasets generated during the current study are not publicly available due to this study is currently in the ongoing research stage, and some of the data cannot be made public sooner yet, but are available from the corresponding author on reasonable request.

6.
Exp Aging Res ; : 1-12, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39003730

RESUMO

BACKGROUND: Cognitive models of depression assert that attentional biases play an important role in the maintenance of depression. However, few studies have explored attentional bias in depressed older adults, and no consistent conclusions have been reached. METHODS: In the current study, we investigated attentional bias in older adults with non-clinical depression. Older adults aged over 60 with non-clinical depression and without depression were instructed to perform a free viewing task while their eye movements were tracked. RESULTS: The results showed that, compared to older adults without depression, non-clinically depressed older adults had longer total fixation durations and a greater number of fixations on sad stimuli. Moreover, non-depressed older adults exhibited a preference for pleasant images, whereas this effect was not observed in older adults with non-clinical depression. CONCLUSION: This study suggested that non-clinically depressed older adults have attentional bias, which is manifested as increased attention to sad stimuli and decreased attention to pleasant stimuli.The current study has functional and potential functional implications.

7.
Nat Med ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965435

RESUMO

Differential diagnosis of dementia remains a challenge in neurology due to symptom overlap across etiologies, yet it is crucial for formulating early, personalized management strategies. Here, we present an artificial intelligence (AI) model that harnesses a broad array of data, including demographics, individual and family medical history, medication use, neuropsychological assessments, functional evaluations and multimodal neuroimaging, to identify the etiologies contributing to dementia in individuals. The study, drawing on 51,269 participants across 9 independent, geographically diverse datasets, facilitated the identification of 10 distinct dementia etiologies. It aligns diagnoses with similar management strategies, ensuring robust predictions even with incomplete data. Our model achieved a microaveraged area under the receiver operating characteristic curve (AUROC) of 0.94 in classifying individuals with normal cognition, mild cognitive impairment and dementia. Also, the microaveraged AUROC was 0.96 in differentiating the dementia etiologies. Our model demonstrated proficiency in addressing mixed dementia cases, with a mean AUROC of 0.78 for two co-occurring pathologies. In a randomly selected subset of 100 cases, the AUROC of neurologist assessments augmented by our AI model exceeded neurologist-only evaluations by 26.25%. Furthermore, our model predictions aligned with biomarker evidence and its associations with different proteinopathies were substantiated through postmortem findings. Our framework has the potential to be integrated as a screening tool for dementia in clinical settings and drug trials. Further prospective studies are needed to confirm its ability to improve patient care.

8.
Natl Sci Rev ; 11(7): nwae195, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39045468

RESUMO

Endogenous opioid antinociception is a self-regulatory mechanism that reduces chronic pain, but its underlying circuit mechanism remains largely unknown. Here, we showed that endogenous opioid antinociception required the activation of mu-opioid receptors (MORs) in GABAergic neurons of the central amygdala nucleus (CEA) in a persistent-hyperalgesia mouse model. Pharmacogenetic suppression of these CEAMOR neurons, which mimics the effect of MOR activation, alleviated the persistent hyperalgesia. Furthermore, single-neuron projection analysis revealed multiple projectome-based subtypes of CEAMOR neurons, each innervating distinct target brain regions. We found that the suppression of axon branches projecting to the parabrachial nucleus (PB) of one subtype of CEAMOR neurons alleviated persistent hyperalgesia, indicating a subtype- and axonal-branch-specific mechanism of action. Further electrophysiological analysis revealed that suppression of a distinct CEA-PB disinhibitory circuit controlled endogenous opioid antinociception. Thus, this study identified the central neural circuit that underlies endogenous opioid antinociception, providing new insight into the endogenous pain modulatory mechanisms.

9.
iScience ; 27(7): 110263, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39040055

RESUMO

Alzheimer's disease (AD) is a complex pathophysiological disease. Allowing for heterogeneity, not only in disease manifestations but also in different progression patterns, is critical for developing effective disease models that can be used in clinical and research settings. We introduce a machine learning model for identifying underlying patterns in Alzheimer's disease (AD) trajectory using longitudinal multi-modal data from the ADNI cohort and the AIBL cohort. Ten biologically and clinically meaningful disease-related states were identified from data, which constitute three non-overlapping stages (i.e., neocortical atrophy [NCA], medial temporal atrophy [MTA], and whole brain atrophy [WBA]) and two distinct disease progression patterns (i.e., NCA → WBA and MTA → WBA). The index of disease-related states provided a remarkable performance in predicting the time to conversion to AD dementia (C-Index: 0.923 ± 0.007). Our model shows potential for promoting the understanding of heterogeneous disease progression and early predicting the conversion time to AD dementia.

10.
World Allergy Organ J ; 17(7): 100926, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39040084

RESUMO

Background: Compliance to sublingual immunotherapy (SLIT) is generally low, resulting in reduced short- and long-term clinical efficacy. Compliance is a critical factor determining the success of allergic rhinitis (AR) treatment. Objective: To analyze the compliance of patients with house dust mite (HDM)-induced AR to SLIT and the impact of coronavirus disease 2019 (COVID-19) on compliance. Methods: The clinical data of 3117 patients with HDM-induced AR who started SLIT between July 2018 and April 2022 were retrospectively reviewed. We assessed the reasons for non-compliance and the changes in non-compliance during the COVID-19 pandemic compared to the pre-pandemic period. Results: Of 3117 patients, 507 (16.27%) patients (ages, 5-67 years) were identified as non-compliant. The most common reason for non-compliance was poor efficacy (27.22%). The non-compliance rate was highest during 24-36 months of SLIT (28.13%, 153/544), followed by 12-24 months (7.02%, 91/1296). Non-compliance was significantly higher in adolescents/adults than in children (P = 0.000). Although the generalized linear model analysis indicated that compliance was affected by the COVID-19 pandemic during 3-6 months of SLIT, the overall compliance to SLIT was not significantly affected by the pandemic, according to the Kaplan-Meier survival analysis. Conclusions: The non-compliance rate of SLIT in this study was low, and poor efficacy was the most common reason for non-compliance. The compliance of adolescents/adults was lower than that of children. The COVID-19 pandemic did not significantly impact compliance to SLIT, which is an appropriate strategy for the home treatment of AR patients during major public health events.

11.
J Agric Food Chem ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042819

RESUMO

Botrytis cinerea is an important fungal pathogen that causes gray mold disease in plants. Previously, Bacillus velezensis TCS001 live culture presented broad-spectrum antifungal activity against various plant pathogenic fungi and oomycetes, particularly B. cinerea. Here, the bioactivity of lipopeptides produced by TCS001 against B. cinerea was investigated. The IC50 values of the crude lipopeptide extract (CLE) from TCS001 to suppress mycelial growth and conidial germination were 14.20 and 49.39 mg/L, respectively. SEM and TEM imaging revealed that CLE caused morphological deformities and ultrastructural changes in the mycelium. Transcriptomic analyses combined with ΔBcpsd mutant construction demonstrated that the CLE could confer antifungal activity via suppressing Bcpsd expression in the pathogen. In addition, the CLE activated the plant immune system by increasing the content of defense-related enzymes and the expression of marker genes in immunity signaling pathways in cucumber plants. Therefore, TCS001 CLE could be potentially developed into biopesticides for the biocontrol of gray mold disease.

12.
Org Lett ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042855

RESUMO

An efficient and operationally simple oxidative radical difunctionalization of N-aryl bicyclobutyl (BCB) amides with aldehydes is described. It was found that acylated 3-spirocyclobutyl oxindoles were generated from the coupling of BCB-amides and aromatic aldehydes, while reactions gave exclusively decarbonylative alkylarylation products using alkyl aldehydes as radical precursors.

13.
BMC Med Educ ; 24(1): 774, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030541

RESUMO

BACKGROUND: The coronavirus disease (COVID-19) pandemic has accentuated the need for effective clinical skills training in infectious diseases. This study aimed to explore the influencing factors of infectious disease clinical skills training based on scenario simulation teaching for medical staff in China. METHODS: This hospital-based, cross-sectional study was conducted at the Third People's Hospital of Shenzhen between March and December 2022. Scenario simulation teaching was applied, and factors such as gender, educational level, professional background, and previous experience were examined to determine their impact on qualification outcomes. RESULTS: The study included participants primarily between the ages of 20-40 years, with a higher proportion of women holding university degrees. Nurses and physicians were more likely to qualify, indicating the significance of professional backgrounds. Women showed a higher likelihood of qualifying than men and higher educational attainment correlated with better qualification rates. Prior experience with protective clothing in isolation wards was a significant determinant of successful qualification. Multivariate analysis underscored the influence of sex, education, and previous experience on training effectiveness. CONCLUSION: Scenario simulation is an effective strategy for training clinical skills in treating infectious diseases. This study highlights the importance of considering sex, education, professional background, and prior experience when designing training programs to enhance the efficacy and relevance of infectious disease training.


Assuntos
COVID-19 , Competência Clínica , Treinamento por Simulação , Humanos , COVID-19/epidemiologia , Estudos Transversais , China , Feminino , Masculino , Adulto , SARS-CoV-2 , Adulto Jovem , Corpo Clínico Hospitalar/educação , Pandemias
14.
Appl Environ Microbiol ; 90(7): e0055724, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38953658

RESUMO

Klebsiella pneumoniae can enter a viable but nonculturable (VBNC) state to survive in unfavorable environments. Our research found that high-, medium-, and low-alcohol-producing K. pneumoniae strains are associated with nonalcoholic fatty liver disease. However, the presence of the three Kpn strains has not been reported in the VBNC state or during resuscitation. In this study, the effects of different strains, salt concentrations, oxygen concentrations, temperatures, and nutrients in K. pneumoniae VBNC state were evaluated. The results showed that high-alcohol-producing K. pneumoniae induced a slower VBNC state than medium-alcohol-producing K. pneumoniae, and low-alcohol-producing K. pneumoniae. A high-salt concentration and micro-oxygen environment accelerated the loss of culturability. Simultaneously, both real-time quantitative PCR and droplet digital PCR were developed to compare the quantitative comparison of three Kpn strain VBNC states by counting single-copy gene numbers. At 22°C or 37°C, the number of culturable cells decreased significantly from about 108 to 105-106 CFU/mL. In addition, imipenem, ciprofloxacin, polymyxin, and phiW14 inhibited cell resuscitation but could not kill VBNC-state cells. These results revealed that the different environments evaluated play different roles in the VBNC induction process, and new effective strategies for eliminating VBNC-state cells need to be further studied. These findings provide a better understanding of VBNC-state occurrence, maintenance, detection, and absolute quantification, as well as metabolic studies of resuscitation resistance and ethanol production.IMPORTANCEBacteria may enter VBNC state under different harsh environments. Pathogenic VBNC bacteria cells in clinical and environmental samples pose a potential threat to public health because cells cannot be found by routine culture. The alcohol-producing Kpn VBNC state was not reported, and the influencing factors were unknown. The formation and recovery of VBNC state is a complete bacterial escape process. We evaluated the influence of multiple induction conditions on the formation of VBNC state and recovery from antibiotic and bacteriophage inhibition, and established a sensitive molecular method to enumerate the VBNC cells single-copy gene. The method can improve the sensitivity of pathogen detection in clinical, food, and environmental contamination monitoring, and outbreak warning. The study of the formation and recovery of VBNC-state cells under different stress environments will also promote the microbiological research on the development, adaptation, and resuscitation in VBNC-state ecology.


Assuntos
Klebsiella pneumoniae , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Antibacterianos/farmacologia , Temperatura , Álcoois/metabolismo , Álcoois/farmacologia
15.
Eur J Immunol ; : e2350655, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973083

RESUMO

Sepsis arises from an uncontrolled inflammatory response triggered by infection or stress, accompanied by alteration in cellular energy metabolism, and a strong correlation exists between these factors. Alpha-ketoglutarate (α-KG), an intermediate product of the TCA cycle, has the potential to modulate the inflammatory response and is considered a crucial link between energy metabolism and inflammation. The scavenger receptor (SR-A5), a significant pattern recognition receptor, assumes a vital function in anti-inflammatory reactions. In the current investigation, we have successfully illustrated the ability of α-KG to mitigate inflammatory factors in the serum of septic mice and ameliorate tissue damage. Additionally, α-KG has been shown to modulate metabolic reprogramming and macrophage polarization. Moreover, our findings indicate that the regulatory influence of α-KG on sepsis is mediated through SR-A5. We also elucidated the mechanism by which α-KG regulates SR-A5 expression and found that α-KG reduced the N6-methyladenosine level of macrophages by up-regulating the m6A demethylase ALKBH5. α-KG plays a crucial role in inhibiting inflammation by regulating SR-A5 expression through m6A demethylation during sepsis. The outcomes of this research provide valuable insights into the relationship between energy metabolism and inflammation regulation, as well as the underlying molecular regulatory mechanism.

16.
Fitoterapia ; 177: 106130, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39032912

RESUMO

A fungus strain, Neopestalotiopsis clavispora AL01, was isolated from the leaf spot of the plant Phoenix dactylifera. Further chemical investigation of the fermentation extract of this strain afforded six new secondary metabolites (1-6), along with 11 known compounds (7-17) which included a new natural compound (7). Their structures were determined by extensive spectroscopic analysis including one-and two-dimensional (1D and 2D) NMR spectroscopy, high-resolution electrospray ionization mass spectrometry (HRESIMS), and ECD and NMR calculations. All compounds were evaluated for their phytotoxic activities. Among them, compounds 10, 12 and 13 exhibited phytotoxic activities against Nicotiana tabacum. Compound 3 exhibited weak antibacterial activity against methicillin-resistant Staphylococcus aureus, Micrococcus luteus and Vibrio harveyi. Taken collectively, these findings establish a solid research foundation for future investigations on bioactive natural products derived from phytopathogenic fungi.

17.
Ann Hematol ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942949

RESUMO

Multiple myeloma (MM) is a form of clonal plasma cell malignancy that associates with clinical manifestations such as anemia, hypercalcemia, bone pain, and renal impairment. Approximately 20-50% of MM patients at initial diagnosis experience renal injury, a vital complication that significantly influences prognosis and quality of life. This review seeks to clarify the multifaceted mechanisms of renal injury in MM, scrutinizing the pathogenic role of monoclonal proteins, the impact of hypercalcemia, and direct renal infiltration by plasma cells. Furthermore, it evaluates current diagnostic approaches, reviews management strategies, and highlights potential avenues for future research. By incorporating the latest scientific evidence and insights, this article aims to provide a comprehensive understanding of MM-associated renal impairment, offering a valuable resource for researchers and clinicians in handling this complex complication.

18.
Gene ; 927: 148727, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38942180

RESUMO

This study aimed to investigate placental microblood flow perfusion in fetal growth restriction (FGR) both pre- and post-delivery, and explore the influence of LINC00473 and its downstream targets on FGR progression in trophoblast cells. Placental vascular distribution, placental vascular index (VIMV), CD34 expression, and histological changes were compared between control and FGR groups. FGR-related differentially expressed genes (DEGs) were analyzed and validated by quantitative real-time polymerase chain reaction (qPCR) and immunohistochemistry (IHC) in placentae. In vitro experiments examined the regulatory relationships among LINC00473, miR-5189-5p, and StAR, followed by investigations into their impacts on cell proliferation and apoptosis. FGR placentae exhibited irregular shapes, uneven parenchymal echo, stromal dysplasia, ischemic infarction, and variable degrees of thickening in some cases. FGR samples showed less prominent mother vessel lakes, significantly lower VIMV, and decreased CD34 expression. Hematoxylin & eosin (H&E) staining revealed placental fibrosis, fibrin adhesion, infarction, and interstitial dysplasia in FGR. LINC00473, miR-5189-5p, and StAR were identified as DEG, with qPCR demonstrating a significant increase in LINC00473 and a decrease in miR-5189-5p in FGR, while both qPCR and IHC indicated a significant increase in StAR expression. LINC00473 served as an endogenous sponge against miR-5189-5p in human HTR-8/SV neo cells, and StAR expression was regulated by both LINC00473 and miR-5189-5p. Dysregulation of these genes affected cell proliferation and apoptosis. Pathological changes in the placenta are significant contributors to FGR, with placental microblood flow potentially serving as an indicator for monitoring its progression. LINC00473 and its downstream targets may modulate trophoblasts proliferation and apoptosis, thus influencing the onset of FGR, suggesting novel avenues for diagnosis and treatment.

19.
Microorganisms ; 12(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38930445

RESUMO

Nitrile-containing insecticides can be converted into their amide derivatives by Pseudaminobacter salicylatoxidans. N-(4-trifluoromethylnicotinoyl) glycinamide (TFNG-AM) is converted to 4-(trifluoromethyl) nicotinoyl glycine (TFNG) using nitrile hydratase/amidase. However, the amidase that catalyzes this bioconversion has not yet been fully elucidated. In this study, it was discovered that flonicamid (FLO) is degraded by P. salicylatoxidans into the acid metabolite TFNG via the intermediate TFNG-AM. A half-life of 18.7 h was observed for P. salicylatoxidans resting cells, which transformed 82.8% of the available FLO in 48 h. The resulting amide metabolite, TFNG-AM, was almost all converted to TFNG within 19 d. A novel amidase-encoding gene was cloned and overexpressed in Escherichia coli. The enzyme, PmsiA, hydrolyzed TFNG-AM to TFNG. Despite being categorized as a member of the amidase signature enzyme superfamily, PsmiA only shares 20-30% identity with the 14 previously identified members of this family, indicating that PsmiA represents a novel class of enzyme. Homology structural modeling and molecular docking analyses suggested that key residues Glu247 and Met242 may significantly impact the catalytic activity of PsmiA. This study contributes to our understanding of the biodegradation process of nitrile-containing insecticides and the relationship between the structure and function of metabolic enzymes.

20.
Sensors (Basel) ; 24(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38931545

RESUMO

Multichannel signals contain an abundance of fault characteristic information on equipment and show greater potential for weak fault characteristics extraction and early fault detection. However, how to effectively utilize the advantages of multichannel signals with their information richness while eliminating interference components caused by strong background noise and information redundancy to achieve accurate extraction of fault characteristics is still challenging for mechanical fault diagnosis based on multichannel signals. To address this issue, an effective weak fault detection framework for multichannel signals is proposed in this paper. Firstly, the advantages of a tensor on characterizing fault information were displayed, and the low-rank property of multichannel fault signals in a tensor domain is revealed through tensor singular value decomposition. Secondly, to tackle weak fault characteristics extraction from multichannel signals under strong background noise, an adaptive threshold function is introduced, and an adaptive low-rank tensor estimation model is constructed. Thirdly, to further improve the accurate estimation of weak fault characteristics from multichannel signals, a new sparsity metric-oriented parameter optimization strategy is provided for the adaptive low-rank tensor estimation model. Finally, an effective multichannel weak fault detection framework is formed for rolling bearings. Multichannel data from the repeatable simulation, the publicly available XJTU-SY whole lifetime datasets and an accelerated fatigue test of rolling bearings are used to validate the effectiveness and practicality of the proposed method. Excellent results are obtained in multichannel weak fault detection with strong background noise, especially for early fault detection.

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