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The antibacterial activity of Cinnamaldehyde against Methicillin-resistant Staphylococcus aureus in Bovine Mastitis is investigated in this study, providing insights into inhibition mechanisms and elucidating the effects on bacterial cell membranes. The Minimum Inhibitory Concentration and Minimum Bactericidal Concentration were determined in this study. In addition, growth curves and a time-kill assay were constructed to assess the antibacterial activity of Cinnamaldehyde. The study revealed that the MIC values ranged from 62.5 to 125 μg/mL, and the MBC values ranged from 125 to 250 μg/mL. The presence of sublethal concentrations of Cinnamaldehyde impeded bacterial growth, while high concentrations demonstrated a significant and rapid bactericidal effect. Subsequently, we examined cell morphology using SEM and TEM, evaluated membrane integrity via laser confocal fluorescence microscopy, and measured levels of β-galactosidase, extracellular DNA release, LDH activity, and ROS, to assess the antibacterial mechanism of Cinnamaldehyde. The findings indicated that with higher concentrations of Cinnamaldehyde, Methicillin-resistant Staphylococcus aureus demonstrated significant morphological alterations and disruption of both the cell wall and membrane. Furthermore, Cinnamaldehyde disrupted the integrity of membranes and increased permeability of the outer membrane in a manner dependent on its concentration. Cinnamaldehyde notably triggered the release of β-galactosidase, extracellular DNA, and LDH, in addition to elevating cellular ROS levels. Finally, the effect of Cinnamaldehyde on the transcription levels of genes related to cell membrane synthesis was assessed using RT-qPCR, and the effect of Cinnamaldehyde on the total protein content of Methicillin-resistant Staphylococcus aureus cells was assessed using WB. The RT-qPCR results showed that Cinnamaldehyde at 1xMIC notably upregulated the transcription levels of genes related to fatty acid biosynthesis in Methicillin-resistant Staphylococcus aureus cell membranes, with a significant or highly significant effect. The WB results showed that Cinnamaldehyde exerts its antibacterial action by suppressing protein expression in Methicillin-resistant Staphylococcus aureus. These findings illustrate that Cinnamaldehyde exerts a potent inhibitory effect on Methicillin-resistant Staphylococcus aureus, establishing a fundamental foundation for the potential use of Cinnamaldehyde essential oil as an antibacterial agent in the treatment of bovine mastitis, in accordance with established scientific standards. [ABSTRACT FROM AUTHOR]

In the process of mining belt transportation, various foreign objects may appear, which will have a great impact on the crusher and belt, thus affecting production progress and causing serious safety accidents. Therefore, it is important to detect foreign objects in the early stages of intrusion in mining belt conveyor systems. To solve this problem, the YOLOv4_GECA method is proposed in this paper. Firstly, the GECA attention module is added to establish the YOLOv4_GECA foreign object detection model in the mineral belt to enhance the foreign object feature extraction capability. Secondly, based on this model, the learning rate decay of restart cosine annealing is used to improve the foreign object image detection performance of the model. Finally, we collected belt transport image information from the Pai Shan Lou gold mine site in Shenyang and established a belt foreign body detection dataset. The experimental results show that the average detection accuracy of the YOLOv4_GECA method proposed in this paper is 90.1%, the recall rate is 90.7%, and the average detection time is 30 ms, which meets the requirements for detection accuracy and real-time performance at the mine belt transportation site. [ABSTRACT FROM AUTHOR]

In the model actinomycete strain, Streptomyces coelicolor, an orphan histidine kinase (HK) named OhkA (encoded by SCO1596), which belongs to bacterial two-component regulatory systems (TCSs), has been identified as being involved in the regulation of both antibiotic biosynthesis and morphological development. However, its cognate response regulator (RR) remains unknown due to its isolated genetic location on the genome, which impedes the elucidation of the mechanism underlying OhkA-mediated regulation. Here, we identified the orphan RR OrrA (encoded by SCO3008) as the cognate RR of OhkA according to mutant phenotypic changes, transcriptomics analysis, and bacterial two-hybrid experiment. Considering that the partner RR of the orphan HK is also orphan, a library of mutants with in-frame individual deletion of these functionally unknown orphan RR-encoding genes were generated. Through phenotypic analysis, it was found that the ∆orrA mutant exhibited similar phenotypic changes as that of the ∆ohkA mutant, showing increased production of actinorhodin (ACT) and undecylprodigiosin (RED), and pink colony surface. Further transcriptomics analysis showed these two mutants exhibited highly similar transcriptomics profiles. Finally, the direct interaction between OhkA and OrrA was revealed by bacterial two-hybrid system. The identification of the partner RR of OhkA lays a good foundation for an in-depth elucidation of the molecular mechanism underlying OhkA-mediated regulation of development and antibiotic biosynthesis in Streptomyces. Key points: • OrrA was identified as the partner RR of the orphan histidine kinase OhkA. • The ∆orrA and ∆ohkA mutants showed similar phenotype and transcriptomic profiling. • Specific interaction of OrrA and OhkA was revealed by bacterial two-hybrid system. [ABSTRACT FROM AUTHOR]

In this study, the aroma components of bead-shaped green teas were compared through headspace solid-phase microextraction (HS-SPME) and gas chromatography–mass spectrometry/olfactometry (GC–MS/O) coupled with chemometrics. A total of 62 volatile compounds were identified in 16 green tea samples. Notably, comparison of GC–MS/O and odour activity values (OAV) results revealed that nonanal, decanal, (E)-2-nonenal, β-ionone, and 1-octen-3-one were the most powerful aroma-active compounds that contributed to the aroma profile of the bead-shaped green teas. Furthermore, multivariate statistical techniques (such as principal component analysis, partial least squares-discriminant analysis, and hierarchical cluster analysis) were used to characterise the bead-shaped green teas according to their geographical origin and the flavour characteristics of their volatile compounds. Additionally, the variable importance in the projection method was used to identify 20 volatile markers that could successfully distinguish bead-shaped green teas on the basis of three flavour characteristics. The results of the analysis revealed that HS-SPME and GC–MS/O coupled with chemometrics can provide an effective method for characterising and classifying bead-shaped green teas. [ABSTRACT FROM AUTHOR]

Thermosensitive LCST phase separation behaviors of poly( N-isopropylacrylamide) (PNIPAM) aqueous solutions have been investigated by a power compensation differential scanning calorimetry which can be subjected to relatively high cooling and heating scanning rates. Significant difference in the thermal properties is observed in four different concentration regions. The typical demixing enthalpy recovery behavior is observed in region III and IV, but cannot be observed in region II. In concentration region I, only one concentration-dependent glass transition behavior can be observed. The distinct thermal features in different concentration regions were interpreted by the complexity of chemical structure, and there are more than one polar groups in the repeating unit of PNIPAM, hydrogen bonded with different numbers of water molecules in different concentration regions. The endothermic phase separation process involved both a chemical process of the breakage of hydrogen bonding between polymer and water molecules and a physical process of the coil-to-globule transition of swelling polymer chains. [ABSTRACT FROM AUTHOR]

Otitis media with effusion (OME) is a common disease and eustachian tube (ET) dysfunction is widely known to be related to the incidence of OME; however, objective evaluation tools for ET function are lacking. To evaluate ET openings by tubomanometry (TMM) in adult patients with otitis media with effusion (OME), the ET patency of 123 ears, including 63 ears of OME patients and 60 control ears, were tested using TMM and tympanometry. ET patency was evaluated by the R value and ET score, and was compared to the tympanogram results. The eustachian tube dysfunction questionnaire (ETDQ-7) was used to assess the severity of the symptoms in OME patients. The results showed that the rates of restricted opening or blocked ET under pressures of 30, 40, and 50 mbar by TMM testing were 10, 5, and 0 %, respectively (control group) and 76.19, 66.7, and 57.97 %, respectively (OME group) ( p < 0.05 for all pressure groups). However, the rates were 77.42, 71.97, and 61.29 % in the type B tympanogram group, and 75, 62.5, and 46.87 % in the type C tympanogram group; no significant difference was found at each testing pressure ( p = 0.821, 0.246, and 0.516; respectively) between these tympanogram groups. The mean ETDQ-7 score in OME patients was 16.40 ± 10.72, which was significantly negatively correlated with the ET score at 30 and 40 mbar (30 mbar: correlation coefficient −0.29, p = 0.025; 40 mbar: correlation coefficient −0.28; p = 0.030), but not at 50 mbar (correlation coefficient −0.013, p = 0.924). These findings showed that ET blockage or delayed opening were found in most adult patients with OME when evaluated by this innovative and semi objective TMM, testing pressures should be considered when assessing the results of TMM in OME patients. [ABSTRACT FROM AUTHOR]

Mosquitocidal Bacillus thuringiensis (Bt) strain S2160-1 was proposed to be an alternative to Bacillus thuringiensis subsp. israelensis (Bti). Discovering and validating a toxic gene by experimentation was a complex and time-consuming task, which can benefit from high-throughput sequencing analysis. In this research, we predicted and identified toxic proteins in the strain S2160-1 based on the draft whole genome sequence data. Through a local BLASP, 46 putative toxins were identified in S2160-1 genome, by searching against a customized B. thuringiensis toxin proteins database containing 653 protein or peptide sequences retrieved from public accessible resources and PCR/clone results in our laboratory (e value = 1e − 5). These putative toxins consist of 42 to 1216 amino acids. The molecular weights are ranged from 4.86 to 137.28 kDa. The isoelectric point of these candidate toxins varied from 4.3 to 10.06, and 16 out of which had a pH greater than 7.0. The analysis of tertiary structure and PFAM domain showed that 12 potential plasmid toxins may share higher similarity (9/12 QMEAN4 score > 0.3) with known Bt toxins. In addition, functional annotation indicated that these 12 potential toxins were involved in “sporulation resulting in formation of a cellular spore” and “toxin activity”. Moreover, multiple alignment and phylogenetic analysis were carried out to elucidate the evolutionary relationship among 101 known crystal or toxin proteins from public database and them with MEGA 6.0. It indicated that PS2160P2_1 and PS2160P2_153 may be potential Cry4-like toxins in Bt S2160-1. This research may lay the foundation for future functional analysis of Bt S2160-1 toxin proteins to reveal their biological roles. [ABSTRACT FROM AUTHOR]

Lipopeptides are important non-ribosomal peptide synthetases (NRPSs) products with broad therapeutic potential in biotechnology and biopharmaceutical applications. Fatty acyl modifications in N-terminal of lipopeptides have attracted wide interest in the engineering processes of altered fatty acyl selectivity. In this study, we focused on the starter condensation domain of antibiotic A54145 (lptC1) and its indiscriminate selectivity of fatty acyl substrates, which results in multi-component products. Using in silico analysis, five site-directed mutations at protein–protein interface were identified with altered activity and selectivity towards wild type lptC1. The variants Y149W and A330T exhibited changed substrate selectivity to prefer longer branched chain fatty acyl substrate, while T16A and A350D showed improved selectivity for shorter linear chain fatty acyl substrates. Subsequently, molecular dynamics (MD) simulations were performed to analyze the impact of these residues on the changes of catalytic activity and conformation. Through in silico analysis, the altered binding free energy were coincident with the corresponding activity performance of the variants, and surface forces indicated that other factors or processes may influence the activity and selectivity. Moreover, the MD results revealed even altered active center conformations, implying the importance of these interface residues affected on distant active center thus reflected to catalysis activity. Based on the biochemistry and computational results, our work provides detailed insights from molecular and dynamics aspects into the role of C1's interface residues during complex NRPS biosynthesis machinery, prompting further rational engineering for lipopeptide catalysis. [ABSTRACT FROM AUTHOR]

MTX in genetically distinctive Chinese psoriatic patients remains less explored. The present study aimed to determine the impact of HLA-Cw*06 on MTX response in a Chinese psoriasis patient population. A total of 204 patients with psoriasis were enrolled in this study. Clinical data and DNA samples from all patients were collected. The allele of HLA-Cw*06 genotyping was detected using direct Sanger sequencing. This study enrolled 204 patients with psoriasis, including 47 (23.04%) psoriatic arthritis patients, 157 (76.96%) patients free of psoriatic arthritis. Overall, 110 (53.92%) of all patients carried the HLA-Cw*06 allele. This frequency in patients with arthritis-free psoriasis was higher than that in those with psoriatic arthritis (58.59 vs. 38.30%, P = 0.014). After 8 weeks of MTX treatment, the arthritis-free psoriasis patients, who tested positive for the HLA-Cw*06 allele, showed significant improvement compared to those who tested negative (For PASI50, 78.57 vs. 55.22%, P = 0.02, and for PASI75, 51.11 vs. 34.33%, P = 0.036). The psoriatic arthritis-free patients who carried the HLA-Cw*06 allele in combination with the ABCB1 rs1045642 CC genotype showed the highest improvement. A regression model containing HLA-Cw*06, rs1045642T > C, and initial PASI scores was used to construct the efficacy prediction model of MTX, which yielded AUC values of 73.2 and 75.6% for PASI50 and PASI75 to MTX, respectively, in arthritis-free psoriasis patients. The HLA-Cw*06 allele is associated with optimal response to MTX treatment in arthritis-free Chinese psoriasis patients. When combined with clinical indicators, the polymorphism explained more than 75% of the individual efficacy differences. [ABSTRACT FROM AUTHOR]

Central nervous system (CNS) relapse of diffuse large B-cell lymphoma (DLBCL) is a rare but devastating event. Intravenous high-dose methotrexate (HD-MTX) is recommended as CNS prophylaxis, but the optimal timing and dose has not been elucidated. Here, we report a multicenter analysis of prophylactic HD-MTX administration for DLBCL. Two hundred eighty-four patients receiving HD-MTX either concurrent with each induction chemotherapy cycle (n = 221) or at the end of induction therapy (EOI, n = 63) were included. Patients with CNS-IPI scoring 4–6, and/or testicular involvement, and/or double/triple hit lymphoma, were stratified into the high-risk group and the others into the moderate-risk group. Concurrent HD-MTX was associated with increased risk of grade 3/4 treatment-related toxicity (OR,1.49; P = 0.006) and subsequent chemotherapy delays (OR, 1.87; P = 0.003) in multivariate analysis. With a median follow-up of 36.0 months, no significant difference in CNS relapse rate was identified between the concurrent and EOI groups (3.2% vs 4.8%, P = 0.34), even in the high-risk group. Analysis on systemic MTX dose suggested that high-dose MTX (≥ 2 g/m2) was associated with better CNS relapse control only in the high-risk group, but not in the moderate-risk group. This study may elucidate the superiority of EOI HD-MTX to some extent. High MTX dose (≥ 2 g/m2) may not be necessary for the moderate-risk patients. [ABSTRACT FROM AUTHOR]

Asthma-induced pulmonary fibrosis (PF) is an important public health concern that has few treatment options given its poorly understood etiology; however, the epithelial to mesenchymal transition (EMT) of pulmonary epithelial cells has been implicated to play an important role in inducing PF. Although previous studies have found atractylon (Atr) to have anti-inflammatory effects, whether Atr has anti-PF abilities remains unknown. The purpose of the current study was to validate the protective efficiency of Atr in both an animal model of ovalbumin (OVA)-induced asthma and an EMT model induced by transforming growth factor-β1 (TGF-β1) using TC-1 cells. The results of this study revealed that Atr treatment suppressed OVA-induced PF via fibrosis-related protein expression. Atr treatment suppressed OVA-induced circRNA-0000981 and TGFBR2 expression but promoted miR-211-5p expression. In vivo studies revealed that Atr suppressed TGF-β1-induced EMT and fibrosis-related protein expression via suppressing circRNA-0000981 and TGFBR2 expression. The results also suggested that the downregulation of circRNA-0000981 expression suppressed TGFBR2 by sponging miR-211-5p, which was validated by a luciferase reporter assay. Collectively, the findings of the present study suggest that Atr treatment attenuates PF by regulating the mmu_circ_0000981/miR-211-5p/TGFBR2 axis in an OVA-induced asthma mouse model. [ABSTRACT FROM AUTHOR]

Background: We aimed to establish a predictive prognostic risk-stratification model for diffuse large B-cell lymphoma (DLBCL) in the rituximab era.Methods: The data of 1406 primary DLBCL patients from the Sun Yat-Sen University Cancer Center were analysed to establish a nomogram prognostic index (NPI) model for predicting overall survival (OS) based on pre-treatment indicators. An independent cohort of 954 DLBCL patients from three other hospitals was used for external validation.Results: Age, performance status, stage, lactate dehydrogenase, number of extranodal sites, BCL2, CD5 expression, B symptoms and absolute lymphocyte and monocyte count were the main factors of the NPI model and could stratify the patients into four distinct categories based on their predicted OS. The calibration curve demonstrated satisfactory agreement between the predicted and actual 5-year OS of the patients. The concordance index of the NPI model (0.794) was higher than the IPI (0.759) and NCCN-IPI (0.750), and similar results were obtained upon external validation. For CD5 + DLBCL patients, systemic treatment with high-dose methotrexate was associated with superior OS compared to R-CHOP-based immunochemotherapy alone.Conclusions: We established and validated an accurate prediction model, which performed better than IPI and NCCN-IPI for prognostic stratification of DLBCL patients. [ABSTRACT FROM AUTHOR]

Long-distance wireless power transmission can reduce the dependence of unmanned systems on energy storage systems, which is especially advantageous for unmanned aerial vehicles. This approach is key for building an integrated and uninterrupted air-to-ground power supply network. This paper introduces the technical characteristics of long-distance wireless power transmission systems, reports the development of such systems at home and abroad, and proposes technical indices and methods for performance evaluation of these systems. A test was conducted using a testing device, and the key parameters of the system performance were obtained. This work provides a solid foundation for the performance evaluation studies of long-distance wireless power transmission systems. [ABSTRACT FROM AUTHOR]