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The complex and dynamic compositions of biofilms, along with their sophisticated structural assembly mechanisms, endow them with exceptional capabilities to thrive in diverse conditions that are typically unfavorable for individual cells. Characterizing biofilms in their native state is significantly challenging due to their intrinsic complexities and the limited availability of noninvasive techniques. Here, we utilized solid-state nuclear magnetic resonance (NMR) spectroscopy to analyze Bacillus subtilis biofilms in-depth. Our data uncover a dynamically distinct organization within the biofilm: a dominant, hydrophilic, and mobile framework interspersed with minor, rigid cores of limited water accessibility. In these heterogeneous rigid cores, the major components are largely self-assembled. TasA fibers, the most robust elements, further provide a degree of mechanical support for the cell aggregates and some lipid vesicles. Notably, rigid cell aggregates can persist even without the major extracellular polymeric substance (EPS) polymers, although this leads to slight variations in their rigidity and water accessibility. Exopolysaccharides are exclusively present in the mobile domain, playing a pivotal role in its water retention property. Specifically, all water molecules are tightly bound within the biofilm matrix. These findings reveal a dual-layered defensive strategy within the biofilm: a diffusion barrier through limited water mobility in the mobile phase and a physical barrier posed by limited water accessibility in the rigid phase. Complementing these discoveries, our comprehensive, in situ compositional analysis is not only essential for delineating the sophisticated biofilm architecture but also reveals the presence of alternative genetic mechanisms for synthesizing exopolysaccharides beyond the known pathway.
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Bacillus subtilis , Biofilmes , Espectroscopia de Ressonância Magnética , Bacillus subtilis/química , Bacillus subtilis/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/metabolismoRESUMO
OBJECTIVE: Over the past decade, heat shock protein 90 (HSP90) inhibitors have emerged as promising anticancer drugs in solid and hematological malignancies. Flavokawain C (FKC) is a naturally occurring chalcone that has been found to exert considerable anti-tumor efficacy by targeting multiple molecular pathways. However, the efficacy of FKC has not been studied in nasopharyngeal carcinoma (NPC). Metabolic abnormalities and uncontrolled angiogenesis are two important features of malignant tumors, and the occurrence of these two events may involve the regulation of HSP90B1. Therefore, this study aimed to explore the effects of FKC on NPC proliferation, glycolysis, and angiogenesis by regulating HSP90B1 and the underlying molecular regulatory mechanisms. METHODS: HSP90B1 expression was analyzed in NPC tissues and its relationship with patient's prognosis was further identified. Afterward, the effects of HSP90B1 on proliferation, apoptosis, glycolysis, and angiogenesis in NPC were studied by loss-of-function assays. Next, the interaction of FKC, HSP90B1, and epidermal growth factor receptor (EGFR) was evaluated. Then, in vitro experiments were designed to analyze the effect of FKC treatment on NPC cells. Finally, in vivo experiments were allowed to investigate whether FKC treatment regulates proliferation, glycolysis, and angiogenesis of NPC cells by HSP90B1/EGFR pathway. RESULTS: HSP90B1 was highly expressed in NPC tissues and was identified as a poor prognostic factor in NPC. At the same time, knockdown of HSP90B1 can inhibit the proliferation of NPC cells, trigger apoptosis, and reduce glycolysis and angiogenesis. Mechanistically, FKC affects downstream EGFR phosphorylation by regulating HSP90B1, thereby regulating the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway. FKC treatment inhibited the proliferation, glycolysis, and angiogenesis of NPC cells, which was reversed by introducing overexpression of HSP90B1. In addition, FKC can affect NPC tumor growth and metastasis in vivo by regulating the HSP90B1/EGFR pathway. CONCLUSION: Collectively, FKC inhibits glucose metabolism and tumor angiogenesis in NPC by targeting the HSP90B1/EGFR/PI3K/Akt/mTOR signaling axis.
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INTRODUCTION: The aim of the study was to investigate differences in the intra- and inter-network functional connectivity (FC) of the brain using resting-state functional magnetic resonance imaging (rs-fMRI) in patients with tinnitus, with (T + H) or without hearing loss (T). METHODS: We performed rs-fMRI on 82 participants (21 T, 32 T + H, and 29 healthy controls). An independent component analysis (ICA) was performed to obtain the resting-state networks (RSNs) and calculate the differences in FC. Moreover, we investigated the relationships between networks using functional network connectivity analysis. RESULTS: We identified nine major RSNs, including the auditory network; default mode network; executive control network (ECN), including the right frontoparietal network and left frontoparietal network (LFPN); somatomotor network (SMN); dorsal attention network; ventral attention network; salience network (SN); and visual network (VN). These RSNs were extracted in all groups using ICA. Compared with that in the control group, we observed reduced FC between the LFPN and VN in the T group and between the LFPN and SN in the T + H group. The inter-network connectivity analysis revealed decreased network interactions in the SMN (IC 22)-ECN (IC 2), SMN (IC 22)-VN (IC 8), and VN (IC 14)-SN (IC 3) connections in the T + H group, compared with the healthy control group. Furthermore, we observed significantly decreased network interactions in the SMN (IC 22)-VN (IC 8) in the T group. CONCLUSIONS: Our results indicated abnormalities within the brain networks of the T and T + H groups, including the SMN, ECN, and VN, compared with the control group. Furthermore, both T and T + H groups demonstrated reduced FC between the LFPN, VN, and SMN. There were no significant differences between the T and the T + H groups. Furthermore, we observed reduced FC between the right olfactory cortex and the orbital part of the right middle frontal gyrus, right precentral gyrus, left dorsolateral superior frontal gyrus, and right triangular part of the inferior frontal gyrus within the T and T + H groups. Thus, disruptions in brain regions responsible for attention, stimulus monitoring, and auditory orientation contribute to tinnitus generation.
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Surdez , Perda Auditiva , Zumbido , Humanos , Mapeamento Encefálico/métodos , Zumbido/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Perda Auditiva/diagnóstico por imagemRESUMO
The plant parasitic nematode Aphelenchoides besseyi is a major pest that poses serious threats to different vegetables and crop plants. In the present study, volatiles isolated from Bacillus spp. were utilized as green biocontrol agents to overcome nematodes. In in vitro experiment, Bacillus spp. GBSC56, SYST2, and FZB42 showed the strongest nematicidal activity with killing rates of 80.78%, 75.69%, and 60.45%, respectively, as compared with control. The selected synthetic volatile organic compounds (VOCs), namely albuterol, benzaldehyde (BDH), 1,2-benzisothiazol-3(2H)-one (1,2-HIT), dimethyl disulfide (DMDS), 2-undecanone (2-UD), and 1,3-propanediole (1,3-PD), exhibited strong nematicidal activity, with A. besseyi killing rate of 85.58%, 82.65%, 81.75%, 80.36%, 84.45%, and 82.36%, respectively, at 400 µg/mL. Microscopic analysis proved that the rapid mortality was due to the production of reactive oxygen species (ROS). Molecular docking attributed this ROS production to the nematicidal effect of synthetic VOCs on NADH DEHYDROGENASE SUBUNIT 2, which is known to play a critical role in the suppression of ROS in nematode models. In a greenhouse experiment, the Bacillus strains GBSC56, SYST2, and FZB42 and their synthetic VOCs significantly improved the physiological parameters in terms of growth promotion traits. In addition, selected genes related to growth promotion and defense genes showed a significant upregulation of their expression in rice seedlings treated with those synthetic VOCs. Overall, these findings revealed that the selected Bacillus strains and their synthetic VOCs possess high potential against A. besseyi. Moreover, this study also sheds new light on the mechanisms by which specific Bacillus nematicidal VOCs influence important genes involved in rice plant growth promotion and could effectively be used to suppress plant parasitic nematodes.
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Bacillus , Nematoides , Oryza , Animais , Espécies Reativas de Oxigênio/metabolismo , Simulação de Acoplamento Molecular , Plantas , Estresse OxidativoRESUMO
The Hippo/Yes-associated protein (YAP) signaling pathway has been shown to be able to maintain organ size and homeostasis by regulating cell proliferation, differentiation, and apoptosis. The abuse of aminoglycosides is one of the main causes of sensorineural hearing loss (SSNHL). However, the role of the Hippo/YAP signaling pathway in cochlear hair cell (HC) damage protection in the auditory field is still unclear. In this study, we used the YAP agonist XMU-MP-1 (XMU) and the inhibitor Verteporfin (VP) to regulate the Hippo/YAP signaling pathway in vitro. We showed that YAP overexpression reduced neomycin-induced HC loss, while downregulated YAP expression increased HC vulnerability after neomycin exposure in vitro. We next found that activation of YAP expression inhibited C-Abl-mediated cell apoptosis, which led to reduced HC loss. Many previous studies have reported that the level of reactive oxygen species (ROS) is significantly increased in cochlear HCs after neomycin exposure. In our study, we also found that YAP overexpression significantly decreased ROS accumulation, while downregulation of YAP expression increased ROS accumulation. In summary, our results demonstrate that the Hippo/YAP signaling pathway plays an important role in reducing HC injury and maintaining auditory function after aminoglycoside exposure. YAP overexpression could protect against neomycin-induced HC loss by inhibiting C-Abl-mediated cell apoptosis and decreasing ROS accumulation, suggesting that YAP could be a novel therapeutic target for aminoglycosides-induced sensorineural hearing loss in the clinic.
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Antibacterianos/efeitos adversos , Células Ciliadas Auditivas/efeitos dos fármacos , Via de Sinalização Hippo/efeitos dos fármacos , Neomicina/efeitos adversos , Proteínas de Sinalização YAP/metabolismo , Animais , Células Ciliadas Auditivas/metabolismo , Células Ciliadas Auditivas/patologia , Camundongos , Fatores de Proteção , Inibidores da Síntese de Proteínas/efeitos adversos , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: During postoperative follow-up, the visible range of maxillary sinus (MS) is limited, even combining 0° and 70° rigid endoscopes together. Flexible endoscope has been used in larynx examinations for a long time, but rarely in nasal cavity and sinus. We aimed to evaluate the application values of rigid and flexible endoscopes for visualization of MS. METHODS: We followed up 70 patients with lesions in MS via both rigid and flexible endoscopes. In addition, we used thin-slice CT image of the sinus to create a MS model and divided it into two parts for 3D printing. The inner surface of the 3D-printed sinus was marked with grid papers of the same size (5 mm × 5 mm), then the visual range under rigid endoscopes with different angle and flexible endoscopes was calculated and analyzed. RESULTS: In clinical follow-up, we found that flexible endoscopy can reach where rigid endoscopy cannot, which is more sensitive than medical imaging. Endoscopes showed the largest observation range of the posterolateral wall, more than half of which can be visualized by 0° endoscope. Almost all of the posterolateral wall can be revealed under 45° endoscope, 70° endoscope and flexible endoscope. The visual range of each wall under flexible endoscope is generally greater than that under rigid endoscopes, especially of the anterior wall, medial wall and inferior wall. CONCLUSION: There was obviously overall advantage of using flexible endoscope in postoperative follow-up of MS lesions. Flexible endoscopy can expand the range of observation, and improve the early detection of the recurrent lesion. We recommend flexible endoscope as a routine application.
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Endoscopia , Seio Maxilar , Endoscópios , Endoscopia/métodos , Humanos , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia , Impressão TridimensionalRESUMO
OBJECTIVE: The aim of this analysis was to evaluate the prognostic significance of inflammatory biomarkers (NLR, dNLR, PLR and LMR) in NPC patients. METHODS: This was a retrospective analysis of 111 NPC patients from January 2013 and December 2016. Receiver-operating characteristic (ROC) curve was plotted to determine the cut-off values of these inflammatory biomarkers. Univariate analysis and multivariate Cox regression model were used to evaluate the association between these parameters and progression-free survival (PFS) and overall survival (OS). RESULTS: The optimal critical value of NLR was 2.02, by which cases were divided into high NLR group (NLR ≥ 2.02) and low NLR group (NLR < 2.02). The elevated NLR was significantly associated with decreased OS (P = 0.009) and remained significant in multivariate analysis (HR 8.48, 95% CI 1.69-42.46, P = 0.009). CONCLUSIONS: The before treatment NLR may be an independent prognostic biomarker for OS in patients with NPC. NLR, dNLR and PLR might be a useful complement to TNM staging in the prognosis evaluation of NPC patients.
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Neoplasias Nasofaríngeas , Neutrófilos , Biomarcadores , Humanos , Linfócitos/patologia , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/terapia , Neutrófilos/patologia , Prognóstico , Estudos RetrospectivosRESUMO
The hygroscopicity and ability of aerosol particles to act as cloud condensation nuclei (CCN) is important in determining their lifetime and role in aerosol-cloud interactions, thereby influencing cloud formation and climate. Previous studies have used the aerosol hygroscopic properties measured at the ground to evaluate the influence on cloud formation in the atmosphere, which may introduce uncertainty associated with aerosol hygroscopicity variability with altitude. In this study, the CCN behaviour and hygroscopic properties of daily filter collections of PM2.5 from three different heights (8, 120, 260 m) on a tower in Beijing were determined in the laboratory using water, water/methanol and methanol as the atomization solvents. Whilst there was substantial temporal variability in particle concentration and composition, there was little obvious difference in aerosol CCN and hygroscopic behaviour at different heights, although the planetary boundary layer height (PBLH) reduced to below the tower height during the nighttime, suggesting that use of surface hygroscopicity measurements is sufficient for the estimation of aerosol particle activation in clouds. Additionally, the critical coating thickness (in terms of mass ratio of coating/refractory BC, MRc) defining the BC transition between being hydrophobic to hydrophilic, was determined by combining hygroscopic tandem differential mobility analyser (H-TDMA), centrifugal particle mass analyzer (CPMA) and single particle soot photometer (SP2) measurements. The MRc of 250 nm BC-containing particles increased from a background value of between 0.8 and 1.6 to around 4.6 at the onset of the growth event of nanoparticles, decreasing monotonically back to the background level as the event progressed. This indicates that large particles do not act as an effective pre-existing condensation sink of the hygroscopic vapours during the nanoparticle growth events, leading to the 250 nm BC particles requiring more coating materials to transition between being hydrophobic and hydrophilic. These findings show that large particles may be less important in suppressing the new particle formation and subsequent growth in the atmosphere.
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This study elaborates inter-kingdom signaling mechanisms, presenting a sustainable and eco-friendly approach to combat biotic as well as abiotic stress in wheat. Fusarium graminearum is a devastating pathogen causing head and seedling blight in wheat, leading to huge yield and economic losses. Psychrophilic Bacillus atrophaeus strain TS1 was found as a potential biocontrol agent for suppression of F. graminearum under low temperature by carrying out extensive biochemical and molecular studies in comparison with a temperate biocontrol model strain Bacillus amyloliquefaciens FZB42 at 15 and 25 °C. TS1 was able to produce hydrolytic extracellular enzymes as well as antimicrobial lipopeptides, i.e., surfactin, bacillomycin, and fengycin, efficiently at low temperatures. The Bacillus strain-induced oxidative cellular damage, ultrastructural deformities, and novel genetic dysregulations in the fungal pathogen as the bacterial treatment at low temperature were able to downregulate the expression of newly predicted novel fungal genes potentially belonging to necrosis inducing protein families (fgHCE and fgNPP1). The wheat pot experiments conducted at 15 and 25 °C revealed the potential of TS1 to elicit sudden induction of plant defense, namely, H2O2 and callose enhanced activity of plant defense-related enzymes and induced over-expression of defense-related genes which accumulatively lead to the suppression of F. graminearum and decreased diseased leaf area.
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Bacillus/genética , Fusarium/genética , Controle Biológico de Vetores , Triticum/microbiologia , Bacillus/crescimento & desenvolvimento , Bacillus/patogenicidade , Resistência à Doença/genética , Fusarium/patogenicidade , Glucanos/genética , Estresse Oxidativo/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Triticum/genética , Triticum/crescimento & desenvolvimentoRESUMO
Commercial shipping is considered as an important source of air pollution and cloud condensation nuclei (CCN). To assess the climatic and environmental impacts of shipping, detailed characterization of ship plumes near the point of emission and understanding of ship plume evolution further downwind are essential. This airborne measurement study presents the online characterization of particulate phase ship emissions in the region of Western Europe in 2019 prior to new international sulfur emission controls becoming enacted. More than 30 ships from both the sulfur emission control area (SECA) in the English Channel and the open sea (OS) are measured and compared. Ships within the SECA emitted much less sulfate (SO4) compared with those at OS. When shifted to a lower apparent fuel sulfur content (FSC) at similar engine loads, the peak of the fresh ship emitting the particle number size distribution shifted from around 60-80 nm in diameter to below 40 nm in diameter. The emission factors (EFs) of sulfate are predicted to decrease by around 94% after the 2020 regulation on ship sulfur emission in the open ocean. The EFs of refractory black carbon (rBC) and organic compounds (Org) do not appear to be directly affected by the lower sulfur contents. The total number concentration for condensation nuclei (CN) >2.5 nm and >0.1 µm are predicated to be reduced by 69 and 56%, respectively. Measured plume evolution results indicate that the S(IV) to S(VI) conversion rate was around 23.4% per hour at the beginning of plume evolution, and the CCN and CN >2.5 nm ratio increased with plume age primarily due to condensation and coagulation. We estimate that the new sulfur emission regulation will lead to a reduction of more than 80% in CCN from fresh ship emissions. The ship-emitted EFs results presented here will also inform emission inventories, policymaking, climate, and human health studies.
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Poluentes Atmosféricos , Navios , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Europa (Continente) , Humanos , Material Particulado/análise , Emissões de Veículos/análiseRESUMO
Several quorum sensing systems occurring in Bacillus subtilis, e.g. Rap-Phr systems, were reported to interact with major regulatory proteins, such as ComA, DegU, and Spo0A, in order to regulate competence, sporulation, and synthesis of secondary metabolites. In this study, we characterized a novel Rap-Phr system, RapA4-PhrA4, in Bacillus velezensis NAU-B3. We found that the rapA4 and phrA4 genes were co-transcribed in NAU-B3. When rapA4 was expressed in the heterologous host Bacillus subtilis OKB105, surfactin production and sporulation were severely inhibited. However, when the phrA4 was co-expressed, the RapA4 activity was inhibited. The transcription of the surfactin synthetase srfA gene and sporulation-related genes were also regulated by the RapA4-PhrA4 system. In vitro results obtained from electrophoretic mobility shift assay (EMSA) proved that RapA4 inhibits ComA binding to the promoter of the srfA operon, and the PhrA4 pentapeptide acts as anti-activator of RapA4. We also found that the F24 residue plays a key role in RapA4 function. This study indicated that the novel RapA4-PhrA4 system regulates the surfactin synthesis and sporulation via interaction with ComA, thereby supporting the bacterium to compete and to survive in a hostile environment. KEY POINTS: â¢Bacillus velezensis NAU-B3 has a novel Rap-Phr quorum sensing system, which does not occur in model strains Bacillus subtilis 168 and B. velezensis FZB42. â¢RapA4-PhrA4 regulates surfactin production and sporulation. â¢RapA4-PhrA4 interacts with the ComA protein from ComP/ComA two-component system.
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Regulação Bacteriana da Expressão Gênica , Esporos Bacterianos , Bacillus , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Esporos Bacterianos/metabolismoRESUMO
OBJECTIVE: The purpose of this study was to systematically evaluate the risk factors of pharyngocutaneous fistula (PCF) after total laryngectomy. METHODS: We systematically searched Pubmed, Web of Science, Cochrane Library, and Embase databases and included the literature according to the inclusion and exclusion criteria. RESULTS: A total of 52 studies with 8605 patients were included in the meta-analysis. The total incidence of PCF was 21% (1808/8605). Meta-analysis results indicated that age (OR = 1.29, 95% CI 1.06-1.58, P = 0.01), smoking (OR = 1.62, 95% CI 1.27-2.07, P < 0.01), COPD (chronic obstructive pulmonary disease) (OR = 1.62, 95% CI 1.19-2.22, P < 0.01), CAD (coronary atherosclerotic heart disease) (OR = 1.82, 95% CI 1.36-2.45, P < 0.01), T-stage (OR = 0.81, 95% CI 0.67-0.98, P = 0.03), previous radiotherapy (OR = 2.41, 95% CI 2.00-2.90, P < 0.01), preoperative albumin (OR = 2.95, 95% CI 1.47-5.91, P < 0.01), preoperative hemoglobin (OR = 1.97, 95% CI 1.28-3.03, P < 0.01), tumor site (OR = 0.28, 95% CI 0.22-0.36, P < 0.01), and treatment method (OR = 1.85, 95% CI 1.44-2.38, P < 0.01) were risk factors associated with PCF. CONCLUSIONS: In our study, age, smoking, COPD, CAD, T-stage, previous radiotherapy, preoperative albumin, preoperative hemoglobin, tumor site, and treatment method were risk factors of PCF.
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Fístula Cutânea/etiologia , Neoplasias Hipofaríngeas/cirurgia , Neoplasias Laríngeas/cirurgia , Laringectomia/efeitos adversos , Doenças Faríngeas/etiologia , Humanos , Laringectomia/métodos , Estudos Retrospectivos , Fatores de RiscoRESUMO
PURPOSE: To explore the application value of continuous suture of the inferior turbinate in inferior turbinate submucosal bone resection. METHODS: Twenty patients with chronic hypertrophic rhinitis with or without nasal septum deviation underwent inferior turbinate submucosal bone resection with or without septoplasty. The inferior turbinate was continuously sutured with or without nasal septum suture after surgery. The nasal cavity was not packed. The postoperative clinical outcome was evaluated using visual analog scales (VASs), saccharin test, nasal endoscopy, and nasal resistance test. Postoperative complications were recorded. RESULTS: All 20 endoscopic surgeries were successfully performed. One day after surgery, the VAS scores of nasal pain (1.3 ± 0.5), headache (0.8 ± 0.4), tearing (0.3 ± 0.3), and bleeding (0.3 ± 0.3) in patients were low; 1 week after surgery, the nasal mucociliary transport time was not significantly prolonged compared to that before surgery (P > 0.05); 1 month after surgery, the symptoms of nasal congestion had improved significantly, as the VAS score for nasal congestion was lower than that before surgery (P < 0.05); the volume of the hypertrophied inferior turbinate of all patients was reduced, the mucous membrane was smooth and rosy, the nasal septum was centrally located, and the total nasal resistance values at 150 Pa pressure had returned to the normal reference range (0.282 ± 0.103 Pa/cm3/s); no complications such as bleeding, nasal infection, nasal dryness, and olfactory disorders occurred. CONCLUSION: After inferior turbinate submucosal bone resection with or without septoplasty, inferior turbinate continuous suture with or without nasal septum suture instead of nasal packing can significantly improve postoperative discomfort, improve nasal ventilation, protect nasal function, and accelerate postoperative recovery.
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Obstrução Nasal , Deformidades Adquiridas Nasais , Rinite , Conchas Nasais , Humanos , Obstrução Nasal/etiologia , Obstrução Nasal/cirurgia , Septo Nasal/cirurgia , Rinite/cirurgia , Suturas , Resultado do Tratamento , Conchas Nasais/cirurgiaRESUMO
Nearly 1400 Bacillus strains growing in the plant rhizosphere were sampled from different sites on the Qinghai-Tibetan Plateau. Forty-five of the isolates, selected due to their biocontrol activity, were genome-sequenced and their taxonomic identification revealed that they were representatives of the Bacillus subtilis species complex (20) and the Bacillus cereus group (9). Majority of the remaining strains were found closely related to Bacillus pumilus, but their average nucleotide identity based on BLAST and electronic DNA/DNA hybridization values excluded closer taxonomic identification. A total of 45 different gene clusters involved in synthesis of secondary metabolites were detected by mining the genomes of the 45 selected strains. Except eight mesophilic strains, the 37 remaining strains were found either cold-adapted or psychrophilic, able to propagate at 10°C and below (Bacillus wiedmannii NMSL88 and Bacillus sp. RJGP41). Pot experiments performed at 10°C with winter wheat seedlings revealed that cold-adapted representatives of B. pumilus, B. safensis and B. atrophaeus promoted growth of the seedlings under cold conditions, suggesting that these bacilli isolated from a cold environment are promising candidates for developing of bioformulations useful for application in sustainable agriculture under environmental conditions unfavourable for the mesophilic bacteria presently in use.
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A major factor limiting bark's industrial use is its greater recalcitrance compared to wood. While lignin is widely recognized as a significant contributor, precise characterization of lignin in bark remains sparse, presenting a crucial gap that impedes understanding of its impact. In this study, we employed advanced solid-state nuclear magnetic resonance (NMR) spectroscopy to analyze bark samples from various species, including willow, poplar, and pine. We established and verified that lignin methoxy peak at 56 ppm serves as a reliable quantitative metric to assess lignin content, with which we calculated the lignin contents in bark are significantly reduced by more than 70% compared to those in wood. Furthermore, in situ characterization revealed significant reduction of ß-ether linkage in bark lignin across species, revealing a more condensed and resistant structural configuration. Our results have substantially advanced our comprehension of the composition and structure of native lignin in tree bark.
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Lignina , Espectroscopia de Ressonância Magnética , Casca de Planta , Populus , Madeira , Lignina/química , Casca de Planta/química , Espectroscopia de Ressonância Magnética/métodos , Populus/química , Madeira/química , Pinus/química , Salix/química , Estrutura Molecular , Árvores/químicaRESUMO
The regional industry network (RIN) is a type of financial network derived from industry networks that possess the capability to describe the connections between specific industries within a particular region. For most investors and financial analysts lacking extensive experience, the decision-support information provided by industry networks may be too vague. Conversely, RINs express more detailed and specific industry connections both within and outside the region. As RIN analysis is domain-specific and current financial network analysis tools are designed for generalized analytical tasks and cannot be directly applied to RINs, new visual analysis approaches are needed to enhance information exploration efficiency. In this study, we collaborated with domain experts and proposed V4RIN, an interactive visualization analysis system that integrates predefined domain knowledge and data processing methods to support users in uploading custom data. Through multiple views in the system panel, users can comprehensively explore the structure, geographical distribution, and spatiotemporal variations of the RIN. Two case studies were conducted and a set of expert interviews with five domain experts to validate the usability and reliability of our system.
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Bacillus spp. has been widely used as a biocontrol agent to control plant diseases. However, little is known about mechanisms of the protein MAMP secreted by Bacillus spp. Herein, our study reported a glycoside hydrolase family 30 (GH30) protein, BpXynC, produced by the biocontrol bacteria Bacillus paralicheniformis NMSW12, that can induce cell death in several plant species. The results revealed that the recombinant protein triggers cell death in Nicotiana benthamiana in a BAK1-dependent manner and elicits an early defense response, including ROS burst, activation of MAPK cascades, and upregulation of plant immunity marker genes. BpXynC was also found to be a glucuronoxylanase that exhibits hydrolysis activity on xlyan. Two mutants of BpXynC which lost the glucuronoxylanase activity still retained the elicitor activity. The qRT-PCR results of defense-related genes showed that BpXynC induces plant immunity responses via an SA-mediated pathway. BpXynC and its mutants could induce resistance in N. benthamiana against infection by Sclerotinia sclerotiorum and tobacco mosaic virus (TMV). Furthermore, BpXynC-treated tomato fruits exhibited strong resistance to the infection of Phytophthora capsica. Overall, our study revealed that GH30 protein BpXynC can induce plant immunity response as MAMP, which can be further applied as a biopesticide to control plant diseases.
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Bacillus , Glicosídeo Hidrolases , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Proteínas , Bacillus/metabolismo , Imunidade Vegetal , Doenças das Plantas/microbiologiaRESUMO
The type VI secretion system (T6SS) of many gram-negative bacteria injects toxic effectors into adjacent cells to manipulate host cells during pathogenesis or to kill competing bacteria. However, the identification and function of the T6SS effectors remains only partly known. Pantoea ananatis, a gram-negative bacterium, is commonly found in various plants and natural environments, including water and soil. In the current study, genomic analysis of P. ananatis DZ-12 causing brown stalk rot on maize demonstrated that it carries three T6SS gene clusters, namely, T6SS-1, T6SS-2, and T6SS-3. Interestingly, only T6SS-1 secretion systems are involved in pathogenicity and bacterial competition. The study also investigated the T6SS-1 system in detail and identified an unknown T6SS-1-secreted effector TseG by using the upstream T6SS effector chaperone TecG containing a conserved domain of DUF2169. TseG can directly interact with the chaperone TecG for delivery and with a downstream immunity protein TsiG for protection from its toxicity. TseG, highly conserved in the Pantoea genus, is involved in virulence in maize, potato, and onion. Additionally, P. ananatis uses TseG to target Escherichia coli, gaining a competitive advantage. This study provides the first report on the T6SS-1-secreted effector from P. ananatis, thereby enriching our understanding of the various types and functions of type VI effector proteins.
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Pantoea , Sistemas de Secreção Tipo VI , Sistemas de Secreção Tipo VI/metabolismo , Pantoea/genética , Sistemas de Secreção Bacterianos/genética , Virulência/genética , Antibacterianos , Chaperonas Moleculares , Proteínas de Bactérias/metabolismoRESUMO
Deafness is the prevailing sensory impairment among humans, impacting every aspect of one's existence. Half of congenital deafness cases are attributed to genetic factors. Studies have shown that Luzp2 is expressed in hair cells (HCs) and supporting cells of the inner ear, but its specific role in hearing remains unclear. To determine the importance of Luzp2 in auditory function, we generated mice deficient in Luzp2. Our results revealed that Luzp2 has predominant expression within the HCs and pillar cells. However, the loss of Luzp2 did not result in any changes in auditory threshold. HCs or synapse number and HC stereocilia morphology in Luzp2 knockout mice did not show any notable distinctions. This was the first study of the role of Luzp2 in hearing in mice, and our results provide important guidance for the screening of deafness genes.