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1.
Nat Commun ; 15(1): 3866, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38719872

ABSTRACT

When unperturbed, granular materials form stable structures that resemble the ones of other amorphous solids like metallic or colloidal glasses. Whether or not granular materials under shear have an elastic response is not known, and also the influence of particle surface roughness on the yielding transition has so far remained elusive. Here we use X-ray tomography to determine the three-dimensional microscopic dynamics of two granular systems that have different roughness and that are driven by cyclic shear. Both systems, and for all shear amplitudes Γ considered, show a cross-over from creep to diffusive dynamics, indicating that rough granular materials have no elastic response and always yield, in stark contrast to simple glasses. For the system with small roughness, we observe a clear dynamic change at Γ ≈ 0.1, accompanied by a pronounced slowing down and dynamical heterogeneity. For the large roughness system, the dynamics evolves instead continuously as a function of Γ. We rationalize this roughness dependence using the potential energy landscape of the systems: The roughness induces to this landscape a micro-corrugation with a new length scale, whose ratio over the particle size is the relevant parameter. Our results reveal the unexpected richness in relaxation mechanisms for real granular materials.

2.
BMC Pulm Med ; 24(1): 235, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38745167

ABSTRACT

BACKGROUND: Emerging evidences have demonstrated that gut microbiota composition is associated with pulmonary arterial hypertension (PAH). However, the underlying causality between intestinal dysbiosis and PAH remains unresolved. METHOD: An analysis using the two-sample Mendelian randomization (MR) approach was conducted to examine the potential causal relationship between gut microbiota and PAH. To assess exposure data, genetic variants associated with 196 bacterial traits were extracted from the MiBioGen consortium, which included a sample size of 18,340 individuals. As for the outcomes, summary statistics for PAH were obtained from the NHGRI-EBI GWAS Catalog, which conducted a meta-analysis of four independent studies comprising a total of 11,744 samples. Causal effects were estimated employing various methods, including inverse variance weighted (IVW), MR-Egger, weighted median, weight mode and simple mode, with sensitivity analyses also being implemented with Cochran's Q test, MR-Egger intercept test, MR-PRESSO, leave-one-out analysis, and funnel plots. RESULTS: Following false discovery rate (FDR) correction, the genetically predicted genus Eubacterium fissicatena group (odds ratio (OR) 1.471, 95% confidence interval (CI) 1.178-1.837, q = 0.076) exhibited a causal association with PAH. In addition, the genus LachnospiraceaeUCG004 (OR 1.511, 95% CI 1.048-2.177) and genus RuminococcaceaeUCG002 (OR 1.407, 95% CI 1.040-1.905) showed a suggestive increased risk of PAH, while genus Eubacterium eligens group (OR 0.563, 95% CI 0.344-0.922), genus Phascolarctobacterium (OR 0.692, 95% CI 0.487-0.982), genus Erysipelatoclostridium (OR 0.757, 95% CI 0.579-0.989) and genus T-yzzerella3 (OR 0.768, 95% CI 0.624-0.945) were found to have nominal protective effect against PAH. CONCLUSION: The findings from our MR study have revealed a potential causal relationship between gut microbiota and PAH. Specifically, we have identified four types of gut microbiota that exhibit a protective effect on PAH, as well as three types that have a detrimental impact on PAH, thereby offering valuable insights for future mechanistic and clinical investigations in the field of PAH.


Subject(s)
Gastrointestinal Microbiome , Mendelian Randomization Analysis , Humans , Gastrointestinal Microbiome/genetics , Pulmonary Arterial Hypertension/genetics , Pulmonary Arterial Hypertension/microbiology , Genome-Wide Association Study , Dysbiosis/genetics , Polymorphism, Single Nucleotide
3.
Int Urogynecol J ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38713240

ABSTRACT

INTRODUCTION AND HYPOTHESIS: Urinary incontinence (UI) is a widespread issue in women that severely impacts quality of life. The addition of sugar is associated with multiple adverse effects on health. This study examined the potential association between added sugar intake and UI. METHODS: Adult females from the National Health and Nutrition Examination Survey database (2005-2018) were included in this study. The primary outcomes were the prevalence of stress urinary incontinence (SUI), urge urinary incontinence (UUI), and mixed urinary incontinence (MUI). Weighted logistic regression, stratified logistic regression, restricted cubic spline regression, and sensitivity analyses were utilized to determine whether added sugar was associated with UI after multivariate adjustment. RESULTS: A total of 14,927 participants met the inclusion criteria. The results revealed a heightened prevalence of SUI, UUI, and MUI in the fourth quartile of added sugar energy percentage (OR = 1.304, 95% confidence interval [CI] = 1.105-1.539; OR = 1.464, 95% CI = 1.248-1.717; OR = 1.657, 95% CI = 1.329-2.065 respectively). The effect was more pronounced in young women and the subgroup analyses did not reveal any noteworthy interaction effects. According to the sensitivity analyses, the results for SUI and the MUI were consistent with those of the primary analyses. CONCLUSIONS: The excessive intake of added sugar among women may increase their risk of SUI and MUI. Our study highlights the negative effects of added sugar on female genitourinary health and highlights the need for universal access to healthy diets.

4.
Adv Mater ; : e2312564, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38692672

ABSTRACT

Fine-tuning nucleation and growth of colloidal liquid crystalline (LC) droplets, also known as tactoids, is highly desirable in both fundamental science and technological applications. However, the tactoid structure results from the trade-off between thermodynamics and nonequilibrium kinetics effects, and controlling liquid-liquid crystalline phase separation (LLCPS) in these systems is still a work in progress. Here, a single-step strategy is introduced to obtain a rich palette of morphologies for tactoids formed via nucleation and growth within an initially isotropic phase exposed to a gradient of depletants. The simultaneous appearance is shown of rich LC structures along the depleting potential gradient, where the position of each LC structure is correlated with the magnitude of the depleting potential. Changing the size (nanoparticles) or the nature (polymers) of the depleting agent provides additional, precise control over the resulting LC structures through a size-selective mechanism, where the depletant may be found both within and outside the LC droplets. The use of depletion gradients from depletants of varying sizes and nature offers a powerful toolbox for manipulation, templating, imaging, and understanding heterogeneous colloidal LC structures.

6.
Int J Surg Case Rep ; 118: 109440, 2024 May.
Article in English | MEDLINE | ID: mdl-38581935

ABSTRACT

INTRODUCTION: The incidence of stage III Kummell's disease without neurological symptoms is increasing in elderly patients with osteoporotic thoracolumbar fractures. However, the surgical method is still controversial in this condition. This report presented a case of Kummell's disease in which percutaneous bone cement-augmented short-segment pedicle screw fixation combined with percutaneous vertebroplasty was performed, providing a reference for the surgical approach. CASE PRESENTATION: The patient was a 72-year-old female who presented unexplained lower back pain accompanied with limited mobility for the past three months. Based on her medical history, physical examinations, and imaging studies, it was confirmed that she had Kummell's disease in stage III without neurological symptoms. We treated her with percutaneous bone cement-augmented short-segment pedicle screw fixation combined with percutaneous vertebroplasty on the symptomatic vertebrae. CLINICAL DISCUSSION: The majority of patients with stage III Kummell's disease have severe osteoporosis, which result in failure of the internal fixation and a series of other complications. Maintaining the stability of the internal fixation system is crucial, especially after screwing and subsequent locking. When augmented with bone cement, the grip and pull-out resistance of the percutaneous pedicle screws enhance greatly. Simultaneously, percutaneous vertebroplasty on the symptomatic vertebrae can immediately support the spine unit's stability mechanically and maintain the shape of the vertebrae after reduction. CONCLUSIONS: The percutaneous bone cement-augmented short-segment pedicle screw fixation combined with percutaneous vertebroplasty on the symptomatic vertebrae is an effective treatment for stage III Kummell's disease without neurological symptoms. It can effectively restore the vertebral height, correct the kyphotic deformities, improve spinal canal stenosis, and achieve satisfactory short-term clinical outcomes.

7.
Neuroscience ; 546: 104-117, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38570062

ABSTRACT

The techniques of tissue clearing have been proposed and applied in anatomical and biomedical research since the 19th century. As we all know, the original study of the nervous system relied on serial ultrathin sections and stereoscopic techniques. The 3D visualization of the nervous system was established by software splicing and reconstruction. With the development of science and technology, microscope equipment had constantly been upgraded. Despite the great progress that has been made in this field, the workload is too complex, and it needs high technical requirements. Abundant mistakes due to manual sections were inescapable and structural integrity remained questionable. According to the classification of tissue transparency methods, we introduced the latest application of transparency methods in central and peripheral nerve research from optical imaging, molecular markers and data analysis. This review summarizes the application of transparent technology in neural pathways. We hope to provide some inspiration for the continuous optimization of tissue clearing methods.


Subject(s)
Peripheral Nerves , Animals , Peripheral Nerves/anatomy & histology , Humans , Imaging, Three-Dimensional/methods
8.
Angew Chem Int Ed Engl ; : e202401635, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38597773

ABSTRACT

The introduction of an abiological catalytic group into the binding pocket of a protein host allows for the expansion of enzyme chemistries. Here, we report the generation of an artificial enzyme by genetic encoding of a non-canonical amino acid that contains a secondary amine side chain. The non-canonical amino acid and the binding pocket function synergistically to catalyze the asymmetric nitrocyclopropanation of α,ß-unsaturated aldehydes by the iminium activation mechanism. The designer enzyme was evolved to an optimal variant that catalyzes the reaction at high conversions with high diastereo- and enantioselectivity. This work demonstrates the application of genetic code expansion in enzyme design and expands the scope of enzyme-catalyzed abiological reactions.

9.
J Clin Neurosci ; 124: 87-93, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38677201

ABSTRACT

BACKGROUND: Antipsychotic medications (APMs) and selective serotonin reuptake inhibitors (SSRIs) are frequently utilized in patients with neuroinflammatory disorders, such as autoimmune encephalitis and multiple sclerosis (MS). This retrospective study investigates how in-hospital treatment with APMs and SSRIs in patients with these neuroinflammatory diseases are associated with differences in hospital length-of-stay (LOS) and mortality. METHODS: We evaluated all the inpatients in the Stanford University Hospital from 2008 to 2023 diagnosed with either non-infectious encephalitis or MS and subdivided them into those who did or did not receive APMs or SSRIs while hospitalized. We then analyzed whether hospital LOS and mortality differed with these medications. RESULTS: Among inpatients with non-infectious encephalitis (n = 114), those who were exposed to APMs had a significantly increased mean LOS (11.8 vs 20.9 days, p < 0.01). For inpatients with MS (n = 1095), treatment with an APM was associated with a significant increase in mean LOS (2.8 vs. 7.1, p < 0.00001). When comparing typical to atypical APMs given to subjects with MS, those who received atypical APMs showed a significant increase in LOS (4.3 vs 10.5, p < 0.01), although typical APMs showed significantly increased risk of mortality (p < 0.05). For inpatients with MS and SSRI use, there was a significant increase in mean hospital LOS (3.5 vs 5.3, p < 0.01), with a significant difference found in those who received fluoxetine or citalopram, but not sertraline or escitalopram. Finally, several healthcare disparities were found, including that Black patients were more likely to receive APMs, and those with MS were more likely to receive typical rather than atypical APMs. Conversely, Black patients with MS were less likely to receive SSRI treatment. CONCLUSIONS: There was a statistically significant increase in LOS associated with APM use in non-infectious encephalitis and MS, as well as with SSRI use in MS. These data reflect the importance of these medications in these neuroinflammatory disorders and suggest that further investigation into their risks and benefits would be warranted.

10.
Phys Med Biol ; 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38657624

ABSTRACT

OBJECTIVE: Automatic and accurate airway segmentation is necessary for lung disease diagnosis. The complex tree-like structures leads to gaps in the different generations of the airway tree, and thus airway segmentation is also considered to be a multi-scale problem. In recent years, convolutional neural networks have facilitated the development of medical image segmentation. In particular, 2D CNNs and 3D CNNs can extract different scale features. Hence, we propose a two-stage and 2D+3D framework for multi-scale airway tree segmentation. APPROACH: In stage 1, we use a 2D Full Airway SegNet(2D FA-SegNet) to segment the complete airway tree. Multi-scale Atros Spatial Pyramid (MASP) and Atros Residual Skip connection (ARSc) modules are inserted to extract different scales feature. We designed a hard sample selection strategy to increase the proportion of intrapulmonary airway samples in stage 2. 3D Airway RefineNet (3D ARNet) as stage 2 takes the results of stage 1 as a priori information. Spatial information extracted by 3D convolutional kernel compensates for the loss of in 2D FA-SegNet. Furthermore, we added False Positive losses and False Negative losses to improve the segmentation performance of airway branches within the lungs. MAIN RESULTS: We performed data enhancement on the publicly available dataset of ISICDM 2020 Challenge 3, and on which evaluated our method. Comprehensive experiments show that the proposed method has the highest DSC of 0.931, and IoU of 0.871 for the whole airway tree and DSC of 0.699, and IoU of 0.543 for the intrapulmonary bronchi tree. In addition, 3D ARNet proposed in this paper cascaded with other State-Of-The-Art methods to increase DLR by up to 46.33% and DBR by up to 42.97%. SIGNIFICANCE: The quantitative and qualitative evaluation results show that our proposed method performs well in segmenting the airway at different scales.

11.
Article in English | MEDLINE | ID: mdl-38634749

ABSTRACT

A Gram-stain-negative bacterium, designated XZ-24T, was isolated from sediment of a river in Mianyang city, Sichuan province, PR China. Cells (1.0-2.0 µm long and 0.4-0.5 µm in width) were strictly aerobic, non-spore-forming, rod shaped, prosthecate and motile by means of a polar flagellum. Growth occurred at 10-37 °C (optimum, 30 °C), at pH 5.0-9.0 (optimum pH 7.0) and with 0-3.0 % (w/v) NaCl (optimum 1.0 % NaCl). The results of phylogenetic analysis based on genomes and 16S rRNA gene sequences indicated that XZ-24T formed a distinct phyletic branch within the family Caulobacteraceae and was most closely related to members of the genera Brevundimonas, Caulobacter and Phenylobacterium with 95.3-96.5 % 16S rRNA gene sequence similarities. The average amino acid identities (AAI) between XZ-24T and species of the family Caulobacteraceae were 47.0-64.5 %, which were below the genus boundary (70 %). The predominant cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0, C18 : 1ω7c 11-methyl and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), the isoprenoid quinone was Q-10, and the major polar lipids were 1,2-di-O-acyl-3-O-α-d-glucopyranuronosyl glycerol; 1,2-di-O-acyl-3-O-[d-glucopyranosyl-(1→4)-α-d glucopyranuronosyl] glycerol and phosphatidylglycerol. The genome size of XZ-24T was 2.64 Mb with a DNA G+C content of 68.9 %. On the basis of the evidence presented in this study, strain XZ-24T represents a novel species of a novel genus in the family Caulobacteraceae, for which the name Peiella sedimenti gen. nov., sp. nov. (Type strain XZ-24T=CCTCC AB 20 23 094T=KCTC 8038T) is proposed.


Subject(s)
Caulobacteraceae , Rivers , Base Composition , Fatty Acids/chemistry , Glycerol , Phylogeny , RNA, Ribosomal, 16S/genetics , Sodium Chloride , Sequence Analysis, DNA , DNA, Bacterial/genetics , Bacterial Typing Techniques
12.
Environ Sci Technol ; 58(15): 6487-6498, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38579165

ABSTRACT

The current understanding of multistress interplay assumes stresses occur in perfect synchrony, but this assumption is rarely met in the natural marine ecosystem. To understand the interplay between nonperfectly overlapped stresses in the ocean, we manipulated a multigenerational experiment (F0-F3) to explore how different temporal scenarios of ocean acidification will affect mercury toxicity in a marine copepod Pseudodiaptomus annandalei. We found that the scenario of past acidification aggravated mercury toxicity but current and persistent acidification mitigated its toxicity. We specifically performed a proteomics analysis for the copepods of F3. The results indicated that current and persistent acidification initiated the energy compensation for development and mercury efflux, whereas past acidification lacked the barrier of H+ and had dysfunction in the detoxification and efflux system, providing a mechanistic understanding of mercury toxicity under different acidification scenarios. Furthermore, we conducted a meta-analysis on marine animals, demonstrating that different acidification scenarios could alter the toxicity of several other metals, despite evidence from nonsynchronous scenarios remaining limited. Our study thus demonstrates that time and duration of ocean acidification modulate mercury toxicity in marine copepods and suggests that future studies should move beyond the oversimplified scenario of perfect synchrony in understanding multistress interaction.


Subject(s)
Mercury , Animals , Mercury/toxicity , Seawater , Ecosystem , Hydrogen-Ion Concentration , Ocean Acidification , Metals
13.
Front Neurol ; 15: 1372231, 2024.
Article in English | MEDLINE | ID: mdl-38560733

ABSTRACT

Objective: To evaluate intracerebral hemorrhage (ICH) risk in patients with ischemic stroke (IS) and cerebral microbleeds (CMBs) undergoing anticoagulation therapy for non-valvular atrial fibrillation (AF). Methods: We conducted a comprehensive search across multiple databases, including Embase, PubMed, Cochrane, UpToDate, Scopus, WOS, and SinoMed. The search covered observational literature published from each database inception until February 1, 2023. We analyzed the prevalence of CMBs during the follow-up period, compared future ICH risk between patients with and without baseline CMBs (CMBs presence/absence, ≧5 CMBs), and examined factors influencing ICH occurrence in patients with CMBs. Also studied recurrent stroke during anticoagulation therapy, the risk of future ICH when white matter hyperintensity (WMH) and CMBs coexist, and the effects of anticoagulants vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs) on future ICH. Results: We included 7 articles involving 5,134 participants. The incidence of CMBs was 24%; baseline CMBs were associated with an increased ICH risk compared to patients without CMBs. ICH-risk was more significant in patients with baseline ≥5 CMBs. After anticoagulant therapy, ICH risk was higher than that of recurrent IS. The risk of future ICH was significantly increased with anticoagulant VKAs compared with NOAC. Conclusion: Anticoagulant therapy for ischemic stroke patients with non-valvular AF and CMBs increases future ICH risk. Discontinuing anticoagulation due to ICH risk should be avoided. NOACs are safe and effective for patients with CMBs and IS.

14.
Front Oncol ; 14: 1380535, 2024.
Article in English | MEDLINE | ID: mdl-38577342

ABSTRACT

Purpose: The aim of this study was to establish a validated nomogram to predict risk factors for major post-operative complications in patients with rectal cancer (RC) by analyzing the factors contributing to major post-operative complications in RC patients. Methods: We retrospectively collected baseline and surgical information on patients who underwent RC surgery between December 2012 and December 2022 at a single-center teaching hospital. The entire cohort was randomly divided into two subsets (60% of the data for development, 40% for validation). Independent risk factors for major post-operative complications were identified using multivariate logistic regression analyses, and predictive models were developed. Area under the curve (AUC) was calculated using receiver operating characteristic curve (ROC) to assess predictive probability, calibration curves were plotted to compare the predicted probability of the nomogram with the actual probability, and the clinical efficacy of the nomogram was assessed using decision curve analysis (DCA). Results: Our study included 3151 patients who underwent radical surgery for RC, including 1892 in the development set and 1259 in the validation set. Forty (2.1%) patients in the development set and 26 (2.1%) patients in the validation set experienced major post-operative complications. Through multivariate logistic regression analysis, age (p<0.01, OR=1.044, 95% CI=1.016-1.074), pre-operative albumin (p<0.01, OR=0.913, 95% CI=0.866-0.964), and open surgery (p<0.01, OR=2.461, 95% CI=1.284-4.761) were identified as independent risk factors for major post-operative complications in RC, and a nomogram prediction model was established. The AUC of the ROC plot for the development set was 0.7161 (95% Cl=0.6397-0.7924), and the AUC of the ROC plot for the validation set was 0.7191 (95% CI=0.6182-0.8199). The predicted probabilities in the calibration curves were highly consistent with the actual probabilities, which indicated that the prediction model had good predictive ability. The DCA also confirmed the good clinical performance of the nomogram. Conclusion: In this study, a validated nomogram containing three predictors was created to identify risk factors for major complications after radical RC surgery. Due to its accuracy and convenience, it could contribute to personalized management of patients in the perioperative period.

15.
Nat Commun ; 15(1): 3561, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38670996

ABSTRACT

Lysine lactylation (Kla) links metabolism and gene regulation and plays a key role in multiple biological processes. However, the regulatory mechanism and functional consequence of Kla remain to be explored. Here, we report that HBO1 functions as a lysine lactyltransferase to regulate transcription. We show that HBO1 catalyzes the addition of Kla in vitro and intracellularly, and E508 is a key site for the lactyltransferase activity of HBO1. Quantitative proteomic analysis further reveals 95 endogenous Kla sites targeted by HBO1, with the majority located on histones. Using site-specific antibodies, we find that HBO1 may preferentially catalyze histone H3K9la and scaffold proteins including JADE1 and BRPF2 can promote the enzymatic activity for histone Kla. Notably, CUT&Tag assays demonstrate that HBO1 is required for histone H3K9la on transcription start sites (TSSs). Besides, the regulated Kla can promote key signaling pathways and tumorigenesis, which is further supported by evaluating the malignant behaviors of HBO1- knockout (KO) tumor cells, as well as the level of histone H3K9la in clinical tissues. Our study reveals HBO1 serves as a lactyltransferase to mediate a histone Kla-dependent gene transcription.


Subject(s)
Histones , Host Cell Factor C1 , Lysine , Transcription, Genetic , Histones/metabolism , Humans , Lysine/metabolism , HEK293 Cells , Animals , Cell Line, Tumor , Transcription Initiation Site , Gene Expression Regulation , Mice , Protein Processing, Post-Translational
16.
Nat Genet ; 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38654131

ABSTRACT

Barnacles are the only sessile lineages among crustaceans, and their sessile life begins with the settlement of swimming larvae (cyprids) and the formation of protective shells. These processes are crucial for adaptation to a sessile lifestyle, but the underlying molecular mechanisms remain poorly understood. While investigating these mechanisms in the acorn barnacle, Amphibalanus amphitrite, we discovered a new gene, bcs-6, which is involved in the energy metabolism of cyprid settlement and originated from a transposon by acquiring the promoter and cis-regulatory element. Unlike mollusks, the barnacle shell comprises alternate layers of chitin and calcite and requires another new gene, bsf, which generates silk-like fibers that efficiently bind chitin and aggregate calcite in the aquatic environment. Our findings highlight the importance of exploring new genes in unique adaptative scenarios, and the results will provide important insights into gene origin and material development.

17.
J Acoust Soc Am ; 155(4): 2517-2537, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38591940

ABSTRACT

The shear stress transport turbulence model is employed to conduct a detailed study of flow characteristics at the highest efficiency point and near-stall point in a full-channel 1.5-stage compressor in this paper. The simulation results for the compressor's total pressure ratio and efficiency exhibit good agreement with experimental data. Emphasis is placed on examining the internal flow structure in the tip area of the compressor rotor under near-stall conditions. The results reveal that significant differences in flow structure primarily occur in the tip area as the compressor approaches stall. Specifically, a reduction in turbulent kinetic energy is observed in a region spanning approximately 20%-60% of the chord length on the rotor suction face near-stall conditions. Two additional peak frequencies, at 0.8 and 1.6 times the blade passage frequency, are observed, and the intricate flow phenomena are elaborated at the near-stall point. The near-stall point exhibits greater noise levels than the highest efficiency point, where the intensity of the surface source increases by more than 10 dB, peaking at 20 dB. This additional peak serves as a significant supplementary noise source near the stall point, leading to a maximum increase of 33.3 dB in the free radiated sound power. The acoustic response within the duct indicates that the compressor operating at the near-stall point continues to produce substantial noise on the actual test bench, showing an average increase of 6 dB in noise levels, and the distribution of the additional peak single-tone noise at the entrance significantly differs from that observed at the highest efficiency point.

18.
Plant Cell Rep ; 43(4): 94, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38472660

ABSTRACT

KEY MESSAGE: Taxadiene synthase, taxadiene-5α-hydroxylase, and taxane 13α-hydroxylase genes were introduced into Nicotiana benthamiana, and the improved resistance to lepidoptera pest fall armyworm was reported. Fall armyworm (FAW) is a serious agricultural pest. Genetic engineering techniques have been used to create pest-resistant plant varieties for reducing pest damage. Paclitaxel is a diterpenoid natural metabolite with antineoplastic effects in medicine. However, the effects of taxanes on the growth and development of lepidoptera pests, such as the FAW, are unknown. Here, selected paclitaxel precursor biosynthesis pathway genes, taxadiene synthase, taxane 5α-hydroxylase, and taxane 13α-hydroxylase, were engineered in the heterologous host Nicotiana benthamiana plants. Bioassay experiments showed that the transgenic N. benthamiana plants displayed improved resistance to FAW infestation, with degeneration of gut tissues and induced expression of apoptosis-related genes. Cytotoxicity experiment showed that the paclitaxel precursor, 10-deacetylbaccatin III, is cytotoxic to Sf9 cells, causing cell cycle arrest at the G2/M phase and disorder of the cytoskeleton. Metabolome analysis showed that heterologous expression of taxane genes in N. benthamiana affected the digestive system, steroid hormone and purine metabolism pathways of FAW larvae. In summary, this study provides a candidate approach for FAW control.


Subject(s)
Bridged-Ring Compounds , Nicotiana , Taxoids , Animals , Spodoptera , Taxoids/metabolism , Taxoids/pharmacology , Paclitaxel/pharmacology , Plants, Genetically Modified/metabolism , Larva
19.
Curr Microbiol ; 81(5): 117, 2024 Mar 16.
Article in English | MEDLINE | ID: mdl-38492090

ABSTRACT

Atrazine is an important herbicide that has been widely used for weed control in recent decades. However, with the extensive use of atrazine, its residue seriously pollutes the environment. Therefore, the microbial degradation and detoxification of atrazine have received extensive attention. To date, the aerobic degradation pathway of atrazine has been well studied; however, little is known about its anaerobic degradation in the environment. In this study, an anaerobic microbial consortium capable of efficiently degrading atrazine was enriched from soil collected from an herbicide-manufacturing plant. Six metabolites including hydroxyatrazine, deethylatrazine, N-isopropylammelide, deisopropylatrazine, cyanuric acid, and the novel metabolite 4-ethylamino-6-isopropylamino-1,3,5-triazine (EIPAT) were identified, and two putative anaerobic degradation pathways of atrazine were proposed: a hydrolytic dechlorination pathway is similar to that seen in aerobic degradation, and a novel pathway initiated by reductive dechlorination. During enrichment, Denitratisoma, Thiobacillus, Rhodocyclaceae_unclassified, Azospirillum, and Anaerolinea abundances significantly increased, dominating the enriched consortium, indicating that they may be involved in atrazine degradation. These findings provide valuable evidence for elucidating the anaerobic catabolism of atrazine and facilitating anaerobic remediation of residual atrazine pollution.


Subject(s)
Atrazine , Herbicides , Soil Pollutants , Atrazine/analysis , Atrazine/chemistry , Atrazine/metabolism , Herbicides/metabolism , Soil/chemistry , Anaerobiosis , Microbial Consortia , Biodegradation, Environmental , Soil Microbiology , Soil Pollutants/metabolism
20.
BMC Public Health ; 24(1): 794, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38481179

ABSTRACT

BACKGROUND: This study aimed to investigate the impact of self-consciousness on depression of college students, and mainly focus on confirming the mediator role of life meaningful and self-efficacy, as well as the moderator role of social support. METHODS: In the present study, convenient sampling method was adopted, 583 college students were recruited from Harbin city and Wenzhou city in China. All students were assessed using self-assessment scales, including self-consciousness scale, life meaningful scale, self-efficacy scale, social support scale, and self-rating depression scale. Descriptive statistical analysis and correlation analysis, structural equation model analysis were conducted by SPSS 25.0 and M-plus. RESULTS: Results showed that self-consciousness was negatively related to depression, life meaningful and self-efficacy partially mediated the relation between self-consciousness and depression. Moderated mediation analysis further indicated that the relation between self-efficacy and depression were moderated bu social support. Compare with college students who had high social support, depression in those with low social support was more susceptible to the effect of self-efficacy. CONCLUSION: These findings imply that college students with low levels of self-consciousness are more easy to be depressive, enhancing their sense of life meaning and self-efficacy can effectively alleviate depression, and college student with high social support can benefit more from self-efficacy. Therefore we should pay more attention to the mental health problems of low levels self-consciousness college students in university.


Subject(s)
Consciousness , Self Efficacy , Humans , Social Support , Emotions , Students
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