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Background and objective: Cognitive-behavioral therapy (CBT) for somatoform disorders (SFDs) is understudied in China. Western findings may not be applicable to Chinese culture. This preliminary study evaluated the efficacy of CBT for patients in China, relative to treatment-as-usual (TAU). Methods: Seventy patients with SFDs randomly received either combined CBT and TAU (CBT + TAU), or TAU alone between January 2018 to May 2019. The CBT + TAU group received 12 weekly individual 50-minute CBT sessions. Participants were blindly assessed at 4 timepoints (baseline, week 6, end of treatment: week 12; 12 weeks post-treatment: week 24) using the following outcome measures: SQSS (Self-screening Questionnaire for Somatic Symptoms); PHQ-15 (Patient-Health-Questionnaire-15) and the WI (Whiteley Index); GAD-7 (General Anxiety Disorder-7); HAMD-17 (Hamilton Depression Rating Scale-17); Family Burden Interview Schedule (FBIS); Sheehan Disability Scale (SDS); and the Short Form of Quality-of-Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q-SF). The primary endpoint was the difference between the SQSS total score at week 24 and the baseline. A mixed model for repeated measures was used to analyze inter- and intra-group changes from the baseline. Results: At week 24, The least-squares mean (LSM) change of the total score on the SQSS was -18.87 points and -9.69 points, respectively in the CBT + TAU group and in the TAU group (LSM difference, -9.18 points; 95% confidence interval, -15.72 to -2.64; P = 0.0068). At week 24, the LSM changes from baseline in the WI, HAMD, PHQ15, FBIS and SDS total scores were significantly different between the two groups, however, there was no significant difference in the Q-LES-Q-SF. The SQSS of group effect sizes were 0.63 at 24 weeks. The dropout rates of the CBT + TAU and TAU groups were comparable (22.9% and 19.3%). Conclusions: These preliminary findings suggest that CBT may be helpful for improving the symptoms of patients with SFDs in China.
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AIMS: PgpH gene has an important regulatory role on bacterial physiological activity, but studies on its regulation mechanism on biofilm formation of Listeria monocytogenes are lacking. Our aim was to investigate the effect of pgpH gene deletion on biofilm formation in L. monocytogenes. METHODS AND RESULTS: The ΔpgpH deletion strain of L. monocytogenes LMB 33 426 was constructed by homologous recombination. Deletion of the pgpH gene resulted in a significant reduction in biofilm formation. The swimming ability of the ΔpgpH strain on semisolid plates was unchanged compared to the wild-type strain (WT), and the auto-aggregation capacity of L. monocytogenes was decreased. RNA-seq showed that ΔpgpH resulted in the differential expression of 2357 genes compared to WT. pgpH inactivation resulted in the significant downregulation of the cell wall formation-related genes dltC, dltD, walK, and walR and the flagellar assembly related genes fliG and motB. CONCLUSIONS: This study shows that the deletion of pgpH gene regulates biofilm formation and auto-aggregation ability of L. monocytogenes by affecting the expression of flagellar assembly and cell wall related genes. pgpH has a global regulatory effect on biofilm formation in L. monocytogenes.
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Biopelículas , Listeria monocytogenes , Listeria monocytogenes/fisiología , Eliminación de Gen , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismoRESUMEN
The purpose of this study was to provide new ideas for the antibacterial mechanism of monolauroyl-galactosylglycerol (MLGG) from the perspective of cell membranes. The changes in cell membrane properties of Bacillus cereus (B. cereus) CMCC 66,301 exposed to different concentrations (1 × MIC (minimum inhibitory concentration), 2 × MIC, 1 × MBC (minimum bacterial concentration)) of MLGG were evaluated. It was found that the lag phase of B. cereus cells was prolonged at low concentration MLGG (1 × MIC and 2 × MIC), while about 2 log CFU/mL reduction in B. cereus populations were observed when exposed to high concentration MLGG (1 × MBC). MLGG treated B. cereus displayed obvious membrane depolarization, while membrane permeability had no change using PI (propidium iodide) staining. Significant increase in the membrane fluidity in response to MLGG exposure occurred, which was consistent with the modification of membrane fatty acids compositions, where the relative content of straight-chain fatty acids (SCFAs) and unsaturated fatty acids (UFAs) increased, while branched-chain fatty acids (BCFAs) decreased significantly. The decreased transition Tm value and cell surface hydrophobicity was also observed. Additionally, effect of MLGG on bacterial membrane compositions were explored at the submolecular level by infrared spectroscopy. Resistance tests of B. cereus to MLGG had demonstrated the advantages of MLGG as a bacteriostatic agent. Collectively, these studies indicate that modifying the fatty acid composition and properties of cellular membranes through MLGG exposure is crucial for inhibiting bacteria growth, providing new insights into the antimicrobial mechanisms of MLGG. KEY POINTS: ⢠Monolauroyl-galactosylglycerol inserted into B. cereus lipid bilayer membrane ⢠Monolauroyl-galactosylglycerol treatment caused B. cereus membrane depolarization ⢠Monolauroyl-galactosylglycerol resulted in B. cereus membrane fatty acids alteration.
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Bacillus cereus , Ácidos Grasos , Ácidos Grasos/metabolismo , Ácidos Grasos Insaturados/metabolismo , Membrana Celular , Fluidez de la MembranaRESUMEN
BACKGROUND: The success of neuroimaging in revealing neural correlates of obsessive-compulsive disorder (OCD) has raised hopes of using magnetic resonance imaging (MRI) indices to discriminate patients with OCD and the healthy. The aim of this study was to explore MRI based OCD diagnosis using machine learning methods. METHODS: Fifty patients with OCD and fifty healthy subjects were allocated into training and testing set by eight to two. Functional MRI (fMRI) indices, including amplitude of low-frequency fluctuation (ALFF), fractional ALFF (fALFF), regional homogeneity (ReHo), degree of centrality (DC), and structural MRI (sMRI) indices, including volume of gray matter, cortical thickness and sulcal depth, were extracted in each brain region as features. The features were reduced using least absolute shrinkage and selection operator regression on training set. Diagnosis models based on single MRI index / combined MRI indices were established on training set using support vector machine (SVM), logistic regression and random forest, and validated on testing set. RESULTS: SVM model based on combined fMRI indices, including ALFF, fALFF, ReHo and DC, achieved the optimal performance, with a cross-validation accuracy of 94%; on testing set, the area under the receiver operating characteristic curve was 0.90 and the validation accuracy was 85%. The selected features were located both within and outside the cortico-striato-thalamo-cortical (CSTC) circuit of OCD. Models based on single MRI index / combined fMRI and sMRI indices underperformed on the classification, with a largest validation accuracy of 75% from SVM model of ALFF on testing set. CONCLUSION: SVM model of combined fMRI indices has the greatest potential to discriminate patients with OCD and the healthy, suggesting a complementary effect of fMRI indices on the classification; the features were located within and outside the CSTC circuit, indicating an importance of including various brain regions in the model.
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Mapeo Encefálico , Trastorno Obsesivo Compulsivo , Humanos , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Aprendizaje AutomáticoRESUMEN
Escherichia coli O157:H7 is a common pathogenic bacterium in food and water that can pose a threat to human health. The aim of this study was to develop loop-mediated isothermal amplification (LAMP) method for the detection of E. coli O157:H7 in food based on the specific gene Ecs_2840 and to construct rapid detection kits based on the established methods. Specifically, we established two methods of real-time fluorescent LAMP (RT-LAMP) and visual LAMP with calcein as an indicator. In pure bacterial culture, the cell sensitivity and genomic sensitivity of the RT-LAMP kit were 8.8 × 100 CFU ml-1 and 4.61 fg µl-1, respectively. The sensitivity of the visual LAMP kit was 2.35 × 100 CFU ml-1 and 4.61 fg µl-1. Both kits had excellent specificity and anti-interference performance. In addition, milk inoculated with 2.26 × 100 CFU ml-1E. coli O157:H7 could be detected within the reaction time after enrichment for 3 h. The results showed that the LAMP kits were rapid, sensitive, and specific for the detection of E. coli O157:H7 in food and had good application prospects in food safety surveillance.
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Escherichia coli O157 , Humanos , Escherichia coli O157/genética , Sensibilidad y Especificidad , Microbiología de AlimentosRESUMEN
Bacillomycin D is a cyclic antimicrobial lipopeptide that has excellent antifungal effects, but its application is limited due to its low yield. At present, it is not clear whether fatty acids regulate the synthesis of bacillomycin D. Therefore, the effects of nine fatty acids on the yield of bacillomycin D produced by Bacillus amyloliquefaciens fmbJ were studied. The results showed that sodium propionate, propionic acid, and butyric acid could increase the yield of bacillomycin D by 44, 40, and 10%, respectively. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression levels of bacillomycin D synthesis gene, signaling factors and genes related to fatty acid metabolism, so as to explore the mechanism of sodium propionate regulating bacillomycin D synthesis. In conclusion, sodium propionate could accelerate the tricarboxylic acid cycle and promoted spore formation, cell movement, the secretion of extracellular protease and the transcription of bacillomycin D synthesis gene by upregulating the expression of signal factors degU, degQ, sigH, sigM and spo0A and ultimately promoted the synthesis of bacillomycin D. In this study, the mechanism of sodium propionate increasing bacillomycin D production was explored from multiple perspectives, which provided theoretical support for the large-scale production of bacillomycin D and was expected to promote its wide application in food, agriculture and medicine fields.
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Péptidos Catiónicos Antimicrobianos , Ácidos Grasos , PropionatosRESUMEN
The synthesis of plantaricin in Lactobacillus plantarum is regulated by quorum sensing. However, the nature of the extra-cytoplasmic (EC) sensing domain of the histidine kinase (PlnB1) and the ability to recognize the auto-inducing peptide PlnA1 is not known. We demonstrate the key motif Ile-Ser-Met-Leu of auto-inducing peptide PlnA1 binds to the hydrophobic region Phe-Ala-Ser-Gln-Phe of EC loop 2 of PlnB1 via hydrophobic interactions and hydrogen bonding. Moreover, we identify a new inducer, acetate, that regulates the synthesis of plantaricin by binding to a positively charged region (Arg-Arg-Tyr-Ser-His-Lys) in loop 4 of PlnB1 via electrostatic interaction. The side chain of Phe143 on loop 4 determined the specificity and affinity of PlnB1 to recognize acetate. PlnA1 activates quorum sensing in log phase growth and acetate in stationary phase to maintain the synthesis of plantaricin under conditions of reduced growth. Acetate activation of PlnB was also evident in four types of PlnB present in different Lb. plantarum strains. Finally, we proposed a model to explain the developmental regulation of plantaricin synthesis by PlnA and acetate. These results have potential applications in improving food fermentation and bacteriocin production.
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Acetatos/metabolismo , Bacteriocinas/metabolismo , Lactobacillus plantarum/metabolismo , Precursores de Proteínas/metabolismo , Percepción de Quorum/fisiología , Bacteriocinas/biosíntesis , Sitios de Unión/fisiología , Interacciones Hidrofóbicas e Hidrofílicas , Lactobacillus plantarum/genética , Unión Proteica/fisiología , Precursores de Proteínas/biosíntesisRESUMEN
Overexpression of Staphylococcus aureus efflux pumps is commonly associated with antibiotic resistance, causing conventional antibiotics to be unsuccessful in combating multidrug-resistant bacterial infections. Reducing the activity of the efflux pump is an urgently required to tackle this problem. Here, we found that plantaricin A (PlnA), an antimicrobial peptide derived from Lactobacillus plantarum, had a synergistic effect with ciprofloxacin (CIP), reducing the IC90 of CIP by eight times. Subsequently, changes in membrane permeability, membrane potential, and reactive oxygen species (ROS) were determined; changes that did not explain the synergistic effect were previously observed. Ethidium bromide intake and efflux experiments showed that PlnA inhibited the function of the efflux pump by binding it and altering the structure of MepA, NorA, and LmrS. Then, a series of PlnA mutants were designed to explore the underlying mechanism; they showed that the charge and foaming of PlnA were the predominant factors affecting the structure of NorA. In a skin wound infection model, PlnA significantly reduced the dose of CIP, relieved inflammation, and promoted wound healing, indicating that PlnA and CIP synergy persisted in vivo. Overall, PlnA reduced the use of CIP for combination therapy, and allowing the continued used of CIP to kill MDR S. aureus. Multidrug-resistant Staphylococcus aureus threatens our life as a tenacious pathogen, which causes infections in hospitals, communities and animal husbandry. Various studies have showed that efflux pump inhibitors (EPIs) have been considered potential therapeutic agents for rejuvenating the activity of antibiotics. Unfortunately, small molecule EPIs exhibit several side effects that limit their use for clinical application. The present study showed a new EPI (plantaricin A) produced by Lactobacillus plantarum, which has low cytotoxicity and haemolysis and powerful inhibitory activity on efflux pumps. Therefore, it helps the design of new EPIs and controls the infection of MDR S. aureus.
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Ciprofloxacina , Staphylococcus aureus Resistente a Meticilina , Antibacterianos/farmacología , Proteínas Bacterianas/química , Bacteriocinas , Ciprofloxacina/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Especies Reactivas de Oxígeno/metabolismo , Farmacorresistencia Bacteriana MúltipleRESUMEN
The outer membrane of Gram-negative bacteria is one of the major factors contributing to the development of antibiotic resistance, resulting in a lack of effectiveness of several hydrophobic antibiotics. Plantaricin A (PlnA) intensifies the potency of antibiotics by increasing the permeability of the bacterial outer membrane. Moreover, it has been proven to bind to the lipopolysaccharide of Escherichia coli via electrostatic and hydrophobic interactions and to interfere with the integrity of the bacterial outer membrane. Based on this mechanism, we designed a series of PlnA1 analogs by changing the structure, hydrophobicity, and charge to enhance their membrane-permeabilizing ability. Subsequent analyses revealed that among the PlnA1 analogs, OP4 demonstrated the highest penetrating ability, weaker cytotoxicity, and a higher therapeutic index. In addition, it decelerated the development of antibiotic resistance when the E. coli cells were continuously exposed to sublethal concentrations of erythromycin and ciprofloxacin for 30 generations. Further in vivo studies in mice with sepsis showed that OP4 heightens the potency of erythromycin against E. coli and relieves inflammation. In summary, our results showed that the PlnA1 analogs investigated in the present study, especially OP4, reduce the intrinsic antibiotic resistance of Gram-negative pathogens and expand the antibiotic sensitivity spectrum of hydrophobic antibiotics in Gram-negative bacteria. IMPORTANCE Antibiotic resistance is a global health concern due to indiscriminate use of antibiotics, resistance transfer, and intrinsic resistance of certain Gram-negative bacteria. The asymmetric bacterial outer membrane prevents the entry of hydrophobic antibiotics and renders them ineffective. Consequently, these antibiotics could be employed to treat infections caused by Gram-negative bacteria, after increasing their outer membrane permeability. As PlnA reportedly penetrates outer membranes, we designed a series of PlnA1 analogs and proved that OP4, one of these antimicrobial peptides, effectively augmented the permeability of the bacterial outer membrane. Furthermore, OP4 effectively improved the potency of erythromycin and alleviated inflammatory responses caused by Escherichia coli infection. Likewise, OP4 curtailed antibiotic resistance development in E. coli, thereby prolonging exposure to sublethal antibiotic concentrations. Thus, the combined use of hydrophobic antibiotics and OP4 could be used to treat infections caused by Gram-negative bacteria by decreasing their intrinsic antibiotic resistance.
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Antibacterianos , Bacteriocinas , Infecciones por Escherichia coli , Animales , Antibacterianos/química , Antibacterianos/farmacología , Bacteriocinas/farmacología , Farmacorresistencia Bacteriana , Eritromicina , Escherichia coli/química , Bacterias Gramnegativas , Interacciones Hidrofóbicas e Hidrofílicas , Ratones , Pruebas de Sensibilidad MicrobianaRESUMEN
Hyperuricemia is a critical threat to human health, and conventional medical treatment only aims to treat acute gouty arthritis. Purine diet-mediated chronic hyperuricemia and related syndromes are neglected in clinical therapeutics. In this study, the prevention ability of Lacticaseibacillus rhamnosus Fmb14, screened from Chinese yogurt, was evaluated in chronic purine-induced hyperuricemia (CPH) mice. After 12 weeks of Fmb14 administration, serum uric acid (SUA) in CPH mice decreased by 36.8 %, from 179.1 to 113.2 µmol/L, and the mortality rate decreased from 30 % to 10 %. The prevention role of Fmb14 in CPH was further investigated, and the reduction of uric acid by Fmb14 was attributed to the reduction of XOD (xanthine oxidase) in the liver and URAT1 in the kidney, as well the promotion of ABCG2 in the colon. Fmb14 administration Increased ZO-1 and Occludin expression in the colon and decreased fibrosis degree in the kidney indicated that Fmb14 administration had preventive effects through the gut-kidney axis in CPH. In specific, Fmb14 administration upregulated the diversity of gut microbiota, increased short-chain fatty acids (SCFA) by 35 % in colon materials and alleviated the inflammatory response by reducing biomarkers levels of IL-1ß, IL-18 and TNF-α at 11.6 %, 21.7 % and 26.5 % in serum, compared to CPH group, respectively. Additionally, 16 S rRNA sequencing showed 31.5 % upregulation of Prevotella, 20.5 % and 21.6 % downregulation of Ruminococcus and Suterella at the genus level, which may be a new gut microbial marker in hyperuricemia. In conclusion, Fmb14 ameliorated CPH through the gut-kidney axis, suggesting a new strategy to prevent hyperuricemia.
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Hiperuricemia , Enfermedades Renales , Animales , Fibrosis , Humanos , Hiperuricemia/inducido químicamente , Hiperuricemia/tratamiento farmacológico , Riñón , Enfermedades Renales/metabolismo , Ratones , Ácido ÚricoRESUMEN
AIMS: A novel endolysin Salmcide-p1 was developed as a promising candidate of new preservative and a supplement to effective enzyme preparations against gram-negative bacterial contaminations. METHODS AND RESULTS: Salmcide-p1 was identified by complementing the genomic sequence of a virulent Salmonella phage fmb-p1. Salmcide-p1 of 112 µg ml-1 could quickly kill Salmonella incubated with 100 mmol l-1 EDTA, with no haemolytic activity. Meanwhile, Salmcide-p1 had a high activity of lysing Salmonella cell wall peptidoglycan. At different temperatures (4-75°C), pH (4-11) and NaCl concentration (10-200 mmol l-1 ), the relative activity of Salmcide-p1 was above 60%. At 4°C, the combination of Salmcide-p1 and EDTA-2Na could inhibit the number of Salmonella Typhimurium CMCC 50115 in skim milk to less than 4 log CFU ml-1 by 3 days, and the number of Shigella flexneri CMCC 51571 was lower than 4 log CFU ml-1 by 9 days. CONCLUSIONS: Salmcide-p1 had a wide bactericidal activity against gram-negative bacteria and showed a broader anti-Salmonella spectrum than the phage fmb-p1. The combination strategy of Salmcide-p1 and EDTA-2Na could significantly inhibit the growth of gram-negative bacteria inoculated in skim milk. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacteriophage endolysin as an antibacterial agent is considered to be a new strategy against bacterial contamination.
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Bacteriófago P1 , Bacteriófagos , Antibacterianos/farmacología , Bacteriófagos/genética , Ácido Edético/farmacología , Endopeptidasas/genética , Endopeptidasas/farmacología , Bacterias Gramnegativas , Salmonella typhimurium/genéticaRESUMEN
Accumulating evidence suggested that suppression of Propionibacterium acnes-induced inflammation was a promising strategy to alleviate acne vulgaris. This study evaluated the alleviating effect of surfactin-oleogel on P. acnes-induced inflammatory acne vulgaris in mice. Epidermis morphology and histopathological examination showed that surfactin-oleogel effectively ameliorated the P. acnes-induced epidermis swelling and erythema. Surfactin-oleogel reduced the epidermis thickness to 48.52% compared to the model control group. The colony of P. acnes in the epidermis was decreased by 1 log CFU/mL after receiving surfactin-oleogel treatment. Furthermore, surfactin-oleogel attenuated oxidative stress in the epidermis by increasing the activities of superoxide dismutase, catalase, and glutathione peroxidase. In addition, the expression of inducible nitric oxide synthase, nitric oxide, cyclooxygenase-2, pro-inflammatory cytokines (e.g. tumour necrosis factor-α and interleukin-1ß), and nuclear factor kappa-B in the epidermis were reduced after treating with surfactin-oleogel. Moreover, total cholesterol and free fatty acids were decreased, whereas the treatment of surfactin-oleogel increased triglycerides and linoleic acid content. Besides, immunohistochemical assay and real-time PCR analysis indicated that surfactin-oleogel blocked the TLR2-mediated NF-κB signalling pathways in the epidermis. Consequently, our results demonstrated that surfactin-oleogel had antibacterial and anti-inflammation activities to treat P. acnes-induced inflammatory acne vulgaris.Key points⢠Surfactin-oleogel effectively relieves inflammation and oxidative stress caused by P. acnes.⢠Surfactin-oleogel effectively reduced the P. acnes colony.⢠Surfactin-oleogel relieves P. acnes-induced inflammation by inactivated the TLR-mediated NF-κB.
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Acné Vulgar , Propionibacterium acnes , Acné Vulgar/tratamiento farmacológico , Animales , Antiinflamatorios/uso terapéutico , Ratones , FN-kappa B , Compuestos OrgánicosRESUMEN
BACKGROUND: Adipokines gene polymorphisms are speculated to be associated with the risk of knee osteoarthritis (OA), but evidence remains conflicting. This study therefore aimed to examine whether associations exist between adipokines gene polymorphisms and knee OA by considering the evidence collected from eligible studies through a meta-analysis. METHODS: A systematic search was performed on PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang up to March 31, 2020. Meta-analysis was carried out by focusing on the associations between adipokines gene polymorphisms and knee OA with the allele model, dominant model, and recessive model. RESULTS: The present meta-analysis included 5 eligible studies for ADIPOQ rs1501299 with 1,021 cases and 1,097 controls, 3 eligible studies for ADIPOQ rs2241766 with 549 cases and 544 controls, 3 eligible studies for LEPR rs1137101 with 808 cases and 856 controls, 2 eligible studies for VISFATIN rs4730153 with 339 cases and 680 controls and 2 eligible studies for VISFATIN rs16872158 with 339 cases and 680 controls. Significant association was observed between LEPR rs1137101 and knee OA in the overall population (recessive: OR = 0.40, 95% CI 0.21-0.79). Limited data revealed that associations may exist between ADIPOQ rs2241766 and knee OA in Asians (dominant: OR = 1.35, 95% CI 1.03-1.78), between VISFATIN rs4730153 and knee OA in Asians (allele: OR = 0.58, 95% CI 0.41-0.83; dominant: OR = 0.57, 95% CI 0.39-0.83), and between VISFATIN rs16872158 and knee OA in Asians (allele: OR = 1.84, 95% CI 1.26-2.68; dominant: OR = 1.94, 95% CI 1.31-2.89). CONCLUSIONS: Adipokines gene polymorphisms may be associated with knee OA. The association was observed in LEPR rs1137101 in the present study. In addition, limited data revealed that associations may also exist in ADIPOQ rs2241766, VISFATIN rs4730153 and VISFATIN rs16872158. PROSPERO REGISTRATION: CRD42020187664.
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Osteoartritis de la Rodilla , Adipoquinas/genética , Adiponectina/genética , Predisposición Genética a la Enfermedad , Humanos , Osteoartritis de la Rodilla/diagnóstico , Osteoartritis de la Rodilla/genética , Polimorfismo de Nucleótido SimpleRESUMEN
Fusarium verticillioides causes ear and kernel rot in maize and produces mycotoxins, like fumonisin B1 (FB1). Bacillomycin D-C16 is a natural antimicrobial lipopeptide produced by Bacillus subtilis. In this study, the inhibitory effects of Bacillomycin D-C16 on the growth of F. verticillioides and on the production of FB1 in maize were investigated. Bacillomycin D-C16 displayed strong fungicidal activity against F. verticillioides, with a minimum inhibitory concentration (MIC) of 32 g/L. Scanning electron microscopy (SEM) showed that Bacillomycin D-C16 altered the morphology of F. verticillioides mycelia. Bacillomycin D-C16 reduced the ergosterol content, increased the release of nucleic acids and proteins, and increased the levels of reactive oxygen species (ROS) in fungal mycelia. Bacillomycin D-C16 also significantly inhibited the production of FB1 by inhibiting mycelial growth and decreasing the levels of fumonisin biosynthetic genes 1 (fum1), fum6 and fum14. The application of Bacillomycin D-C16 on maize kernels prior to storage inhibited the growth of F. verticillioides and the production of FB1. Our results suggested that Bacillomycin D-C16 has a significant antifungal activity that could be used as a potential natural antimicrobial agent to control food contamination and to ensure food safety.
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Fumonisinas , Fusarium , Péptidos Catiónicos Antimicrobianos , Zea maysRESUMEN
The advancement of autonomous driving technology has had a significant impact on both transportation networks and people's lives. Connected and automated vehicles as well as the surrounding driving environment are increasingly exchanging information. The traditional open road test or closed field test, which has large costs, lengthy durations, and few diverse test scenarios, cannot satisfy the autonomous driving system's need for reliable and safe testing. Functional testing is the emphasis of the test since features such as frontal collision and traffic sign warning influence driving safety. As a result, simulation testing will undoubtedly emerge as a new technique for unmanned vehicle testing. A crucial aspect of simulation testing is the creation of test scenarios. With an emphasis on the map generating method and the dynamic scenario production method in the test scenarios, this article explains many scenarios and scenario construction techniques utilized in the process of self-driving car testing. A thorough analysis of the state of relevant research is conducted, and approaches for creating common scenarios as well as brand-new methods based on machine learning are emphasized.
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Accidentes de Tránsito , Conducción de Automóvil , Humanos , Accidentes de Tránsito/prevención & control , Seguridad , Vehículos Autónomos , Simulación por ComputadorRESUMEN
Surfactin from Bacillus amyloliquefaciens fmb50 was utilized to treat mice with type 2 diabetes (T2DM) induced by a high-fat diet/streptozotocin (HFD/STZ). Our group's earlier research indicated that surfactin could lower blood glucose and mitigate liver dysfunction to further improve HFD/STZ-induced T2DM through modulating intestinal microbiota. Thus, we further investigated the effects of surfactin on the pancreas and colon in mice with T2DM to elucidate the detailed mechanism. In the present study, mice with HFD/STZ-induced T2DM had their pancreatic and colon inflammation, oxidative stress, and endoplasmic reticulum stress (ERS) reduced when given oral surfactin at a dose of 80 mg/kg body weight. According to further research, surfactin also improved glucose metabolism by activating the phosphatidylinositol kinase (PI3K)/protein kinase B (Akt) signaling pathway, further protecting islets ß-cell, promoting insulin secretion, inhibiting glucagon release and mitigating pancreas dysfunction. Additionally, after surfactin treatment, the colon levels of the tight junction proteins Occludin and Claudin-1 of T2DM mice were considerably increased by 130.64% and by 36.40%, respectively. These findings revealed that surfactin not only ameliorated HFD/STZ-induced pancreas inflammation and dysfunction and preserved intestinal barrier dysfunction and gut microbiota homeostasis but also enhanced insulin sensitivity and glucose homeostasis in T2DM mice. Finally, in the further experiment, we were able to demonstrate that early surfactin intervention might delay the development of T2DM caused by HFD/STZ, according to critical biochemical parameters in serum.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Animales , Glucemia/metabolismo , Claudina-1 , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dieta Alta en Grasa/efectos adversos , Glucagón , Glucosa/metabolismo , Inflamación/complicaciones , Inflamación/tratamiento farmacológico , Ratones , Ocludina , Páncreas/metabolismo , Hormonas Pancreáticas , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositoles/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , EstreptozocinaRESUMEN
Type I L-asparaginase from Bacillus licheniformis Z-1 (BlAase) was efficiently produced and secreted in Bacillus subtilis RIK 1285, but its low yield made it unsuitable for industrial use. Thus, a combined method was used in this study to boost BlAase synthesis in B. subtilis. First, fifteen single strong promoters were chosen to replace the original promoter P43, with PyvyD achieving the greatest BlAase activity (436.28 U/mL). Second, dual-promoter systems were built using four promoters (PyvyD, P43, PaprE, and PspoVG) with relatively high BlAase expression levels to boost BlAase output, with the engine of promoter PaprE-PyvyD reaching 502.11 U/mL. The activity of BlAase was also increased (568.59 U/mL) by modifying key portions of the PaprE-PyvyD promoter. Third, when the ribosome binding site (RBS) sequence of promoter PyvyD was replaced, BlAase activity reached 790.1 U/mL, which was 2.27 times greater than the original promoter P43 strain. After 36 h of cultivation, the BlAase expression level in a 10 L fermenter reached 2163.09 U/mL, which was 6.2 times greater than the initial strain using promoter P43. Moreover, the application potential of BlAase on acrylamide migration in potato chips was evaluated. Results showed that 89.50% of acrylamide in fried potato chips could be removed when combined with blanching and BlAase treatment. These findings revealed that combining transcription and translation techniques are effective strategies to boost recombinant protein output, and BlAase can be a great candidate for controlling acrylamide in food processing.
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Asparaginasa , Bacillus subtilis , Acrilamidas , Asparaginasa/genética , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Alimentos , Regiones Promotoras Genéticas , Proteínas Recombinantes/metabolismoRESUMEN
Bacteriocins are useful for controlling the composition of microorganisms in fermented food. Bacteriocin synthesis is regulated by quorum sensing mediated by autoinducing peptides. In addition, short-chain fatty acids, especially acetic acid, reportedly regulate bacteriocin synthesis. Five histidine kinases that regulated the synthesis of bacteriocins were selected to verify their interactions with acetate. Acetate activated the kinase activity of PlnB, SppK, and HpK3 in vitro and increased the yield of their cognate bacteriocins plantaricin EF, sakacin A, and rhamnosin B in vivo. The antimicrobial activity against Staphylococcus aureus of the fermentation supernatants of Lactobacillus plantarum, Lactobacillus sakei, and Lactobacillus rhamnosus with addition of acetate increased to 298%, 198%, and 289%, respectively, compared with that in the absence of acetate. Our study elucidated the activation activity of acetate in bacteriocin synthesis, and it might provide a potential strategy to increase the production of bacteriocin produced by Lactobacillus. IMPORTANCE Bacteriocins produced by lactic acid bacteria (LAB) are particularly useful in food preservation and food safety. Bacteriocins might increase bacterial competitive advantage against the indigenous microbiota of the intestines; at the same time, bacteriocins could limit the growth of undesired microorganisms in yogurt and other dairy products. This study confirmed that three kinds of histidine kinases were activated by acetate and upregulated bacteriocin synthesis both in vitro and in vivo. The increasing yield of bacteriocins reduced the number of pathogens and increased the number of probiotics in milk. Bacteriocin synthesis activation by acetate may have a broad application in the preservation of dairy products and forage silage.
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Acetatos/farmacología , Antibacterianos/biosíntesis , Bacteriocinas/biosíntesis , Lactobacillus/efectos de los fármacos , Percepción de Quorum/efectos de los fármacos , Fermentación , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Histidina Quinasa/genética , Histidina Quinasa/metabolismo , Lactobacillus/metabolismo , Lactobacillus/fisiología , Staphylococcus aureus/crecimiento & desarrolloRESUMEN
BACKGROUND: Cognitive behavioural therapy (CBT) is considered an effective first-line treatment for obsessive-compulsive disorder (OCD). However, the neural basis of CBT for OCD has not yet been elucidated. The role of the amygdala in OCD and its functional coupling with the cerebral cortex have received increasing attention, and may provide new understanding of the neural basis of CBT for OCD. METHODS: We acquired baseline resting-state functional MRI (fMRI) scans from 45 unmedicated patients with OCD and 40 healthy controls; we then acquired another wave of resting-state fMRI scans from the patients with OCD after 12 weeks of CBT. We performed seed-based resting-state functional connectivity analyses of the amygdala subregions to examine changes in patients with OCD as a result of CBT. RESULTS: Compared to healthy controls, patients with OCD showed significantly increased resting-state functional connectivity at baseline between the left basolateral amygdala and the right middle frontal gyrus, and between the superficial amygdala and the right cuneus. In patients with OCD who responded to CBT, we found decreased resting-state functional connectivity after CBT between the amygdala subregions and the visual association cortices and increased resting-state functional connectivity between the amygdala subregions and the right inferior parietal lobe. Furthermore, these changes in resting-state functional connectivity were positively associated with changes in scores on the compulsion or obsession subscales of the Yale-Brown Obsessive-Compulsive Scale. LIMITATIONS: Because of the lack of a second scan for healthy controls after 12 weeks, our results may have been confounded by other variables. CONCLUSION: Our findings yield insights into the pathophysiology of OCD; they also reveal the potential neural changes elicited by CBT, and thus have implications for guiding effective treatment strategies with CBT for OCD.
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Terapia Cognitivo-Conductual , Trastorno Obsesivo Compulsivo , Amígdala del Cerebelo/diagnóstico por imagen , Mapeo Encefálico , Humanos , Imagen por Resonancia Magnética , Vías Nerviosas/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/terapiaRESUMEN
Brevibacillins are broad-spectrum cationic antimicrobial lipopeptides produced by Brevibacillus laterosporus fmb70 CGMCC 18426. The antibacterial mode of brevibacillins against Salmonella typhimurium CICC 21493 was investigated by quantum chemistry calculation in this study. The addition of LPS, Mg2+, and Ca2+ partially reduced the antimicrobial activity of brevibacillin and brevibacillin V against S. typhimurium, which indicated that the two cationic lipopeptides could bind to LPS and displaced the divalent cations on the LPS network. Release of LPS from S. typhimurium by brevibacillin and brevibacillin V resulted in destroying the dense LPS network and increasing the permeability of the outer membrane. Quantum chemistry calculation analysis revealed that Lys7 is the most critical amino acid residue to destroy the outer membrane. The total average N-H charge difference of the three protonated amino groups (Orn3-NH3, Lys7-NH3, and Lys10-NH3) determined the ability of brevibacillin V to bind LPS stronger than brevibacillin. Calcein complete leakage from liposomes and release of DiSC3-5 from the cytoplasmic membrane (CM) indicated that brevibacillin and brevibacillin V may destroy the CM. Brevibacillin and brevibacillin V exhibited their antimicrobial activities through membrane damages, where the OM permeability with high concentration of 64-256 µg/mL and membrane damage of CM with a low concentration of 4 µg/mL. Our finding might be helpful to understand the broad-spectrum antimicrobial mechanism of cationic lipopeptide and to design the novel antimicrobial peptide. KEY POINTS: ⢠Brevibacillin V had stronger affinity for LPS than brevibacillin. ⢠The N-H charge difference was the key of the difference in the affinity to LPS. ⢠Brevibacillins inhibited Salmonella by displacing the divalent cations on the LPS.