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The diversity and delicate balance of the oral microbiome contribute to oral health, with its disruption leading to oral and systemic diseases. Toothpaste includes elements like traditional additives such as sodium lauryl sulfate (SLS) as well as novel postbiotics derived from probiotics, which are commonly employed for maintaining oral hygiene and a healthy oral cavity. However, the response of the oral microbiota to these treatments remains poorly understood. In this study, we systematically investigated the impact of SLS, and toothpaste containing postbiotics (hereafter, postbiotic toothpaste) across three systems: biofilms, animal models, and clinical populations. SLS was found to kill bacteria in both preformed biofilms (mature biofilms) and developing biofilms (immature biofilms), and disturbed the microbial community structure by increasing the number of pathogenic bacteria. SLS also destroyed periodontal tissue, promoted alveolar bone resorption, and enhanced the extent of inflammatory response level. The postbiotic toothpaste favored bacterial homeostasis and the normal development of the two types of biofilms in vitro, and attenuated periodontitis and gingivitis in vivo via modulation of oral microecology. Importantly, the postbiotic toothpaste mitigated the adverse effects of SLS when used in combination, both in vitro and in vivo. Overall, the findings of this study describe the impact of toothpaste components on oral microflora and stress the necessity for obtaining a comprehensive understanding of oral microbial ecology by considering multiple aspects.
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BACKGROUND: Hair loss is a widespread health problem that affects numerous individuals and is associated with age, lack of sleep, stress, endocrine problems, and other problems. Caffeine exerts various pharmacological effects, particularly after ingestion. The caffeine-induced inhibition of phosphodiesterases can increase intracellular cAMP concentrations, ultimately resulting in stimulatory effects on cell metabolism and proliferation. Hence, caffeine has been confirmed to inhibit hair loss caused by premature termination of the hair growth phase. Adenosine also improves hair loss by stimulating hair growth and thickening hair shafts. However, further empirical evidence is required to comprehensively assess the efficacy of hair loss treatment and prevention using a formulation of caffeine and adenosine in specific proportions in shampoos. OBJECTIVES: This study aimed to evaluate a shampoo with caffeine and adenosine as a daily scalp care product for hair loss in 77 subjects aged 18-60 years. METHODS: The overall and local hair densities were assessed using professional cameras and dermoscopes at different magnifications and distances. Five hairs that came off the participant's head were randomly selected to measure hair diameter. The self-assessment questionnaires were filled on third month of product use. RESULTS: The combination of caffeine and adenosine in the shampoo significantly enhanced hair density compared to that of the baseline. The results revealed a significant reduction in hair loss. The hair diameters of the subjects did not change significantly. Most of the participants (71.05%) were satisfied with their hair after using the product. CONCLUSIONS: Shampoos containing caffeine and adenosine have been demonstrated to exert therapeutic benefits for reducing hair loss.
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Adenosina , Alopecia , Cafeína , Preparações para Cabelo , Cabelo , Humanos , Cafeína/administração & dosagem , Cafeína/farmacologia , Adulto , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Masculino , Adenosina/administração & dosagem , Preparações para Cabelo/farmacologia , Preparações para Cabelo/administração & dosagem , Adolescente , Alopecia/tratamento farmacológico , Cabelo/efeitos dos fármacos , Cabelo/crescimento & desenvolvimento , Resultado do TratamentoRESUMO
BACKGROUND: The human skin microbiome and lipidome are essential for skin homeostasis and barrier function, and have become a focus in both dermatological and cosmetic fields. However, the influence of surfactants commonly used in cosmetic products on the skin resident microbiome and lipidome remains poorly characterized. METHODS: We conducted self-control experiments to systematically study the effects of surfactant (sodium lauroyl sarcosinate [SLS]) on facial skin. Wrinkles, pores, porphyrins, and superficial lipids were examined to evaluate the biophysical state of skin. Quantitative real-time PCR was used to detect the numbers of bacteria and fungi. The diversity and structure of prokaryotic and eukaryotic microbiomes were assessed using 16S rDNA and ITS amplicon sequencing, respectively. Moreover, 22 lipids were identified to evaluate lipidome variations. SPSS software was used for statistical analysis. RESULTS: SLS in facial cleanser did not extensively influence skin biophysical parameters, but caused a decrease in porphyrin. After using the SLS-added facial cleanser for 3 weeks, the alpha diversity of the prokaryotic microbial community decreased significantly, while the eukaryotic microbial community showed a continuous downward trend but no statistically significant. A shift in the structure of prokaryotic microbiome was observed as a result of SLS exposure, mainly reflected by the increase in Acinetobacter, Escherichia-Shigella, Streptococcus, and Ralstonia, while the SLS had little effect on the structure of the eukaryotic microbiome. Furthermore, SLS exposure had a great impact on skin lipidome, mainly manifested by the increase of phosphatidylglycerol (PG) and phosphatidylcholine (PC), and the decrease of ceramides. Spearman's correlations analysis showed that Escherichia-Shigella, Pseudomonas, and Acinetobacter are positively correlated with PG and PC; however, the correlation is not statistically significant. CONCLUSION: In this study, we found the SLS in facial cleanser primarily affected lipidome and the prokaryotic microbiome of facial skin. These findings are useful for reminding us to be vigilant about the ingredients in personal care products, even the common ingredients, and designing effective formulations for repairing ecological balance of skin.
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Cosméticos , Microbiota , Sarcosina/análogos & derivados , Humanos , Lipidômica , Pele , Tensoativos , Cosméticos/farmacologia , Lipídeos/farmacologiaRESUMO
Nanocatalytic-based wound therapeutics present a promising strategy for generating reactive oxygen species (ROS) to antipathogen to promote wound healing. However, the full clinical potential of these nanocatalysts is limited by their low reactivity, limited targeting ability, and poor biodegradability in the wound microenvironment. Herein, a bio-organic nanozyme is developed by encapsulating a FeZn-based bimetallic organic framework (MOF) (MIL-88B-Fe/Zn) in platelet membranes (PM@MIL-88B-Fe/Zn) for antimicrobial activity during wound healing. The introduction of Zn in MIL-88B-Fe/Zn modulates the electronic structure of Fe thus accelerating the catalytic kinetics of its peroxidase-like activity to catalytically generate powerful ROS. The platelet membrane coating of MOF innovatively enhanced the interaction between nanoparticles and the biological environment, further developing bacterial-targeted therapy with excellent antibacterial activity against both gram-positive and gram-negative bacteria. Furthermore, this nanozyme markedly suppressed the levels of inflammatory cytokines and promoted angiogenesis in vivo to effectively treat skin surface wounds and accelerate wound healing. PM@MIL-88B-Fe/Zn exhibited superior biodegradability, favourable metabolism and non-toxic accumulation, eliminating concerns regarding side effects from long-term exposure. The high catalytic reactivity, excellent targeting features, and biodegradability of these nanoenzymes developed in this study provide useful insights into the design and synthesis of nanocatalysts/nanozymes for practical biomedical applications.
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Antibacterianos , Estruturas Metalorgânicas , Cicatrização , Antibacterianos/farmacologia , Antibacterianos/química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Animais , Cicatrização/efeitos dos fármacos , Plaquetas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Camundongos , HumanosRESUMO
BACKGROUND: Skin aging is a complex multifactorial progressive process. With age, intrinsic and extrinsic factors cause the loss of skin elasticity, with the formation of wrinkles, resulting in skin sagging through various pathways. A combination of multiple bioactive peptides could be used as a treatment for skin wrinkles and sagging. OBJECTIVES: This study aimed to evaluate the cosmetic efficacy of a multi-peptide eye serum as a daily skin-care product for improving the periocular skin of women within the ages of 20-45 years. METHODS: The stratum corneum skin hydration and skin elasticity were assessed using a Corneometer CM825 and Skin Elastometer MPA580, respectively. The PRIMOS CR technique based on digital strip projection technology was used for skin image and wrinkle analysis around the "crow's feet" area. Self-assessment questionnaires were filled on Day 14 and 28 of product use. RESULTS: This study included 32 subjects with an average age of 28.5 years. On Day 28, there was a significant decrease in the number, depth, and volume of wrinkles. Skin hydration, elasticity, and firmness increased continuously during the study period, consistent with typical anti-aging claims. A majority of the participants (75.00%) expressed overall satisfaction with their skin appearance after using the product. Most participants noted a visible skin improvement, with an increase in skin elasticity and smoothness, and confirmed the extensibility, applicability, and temperance of the product. No adverse reactions related to product use were observed. CONCLUSIONS: The multi-peptide eye serum uses a multi-targeted mechanism against skin aging to improve the skin appearance, making it an ideal choice for daily skincare.
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Cosméticos , Envelhecimento da Pele , Humanos , Feminino , Adulto , Pele/diagnóstico por imagem , Peptídeos/efeitos adversos , Cosméticos/uso terapêutico , EnvelhecimentoRESUMO
Titanium dioxide nanoparticles (TiO2 NPs) are generally added in considerable amounts to food as a food additive. Oral exposure to TiO2 NPs could induce intestinal damage, especially in obese individuals with a high-fat diet. The probiotic Bacillus coagulans (B. coagulans) exhibits good resistance in the gastrointestinal system and is beneficial to intestinal health. In this study, B. coagulans was used to treat intestinal damage caused by TiO2 NPs in high-fat-diet mice via two intervention methods: administration of TiO2 NPs and B. coagulans simultaneously and administration of TiO2 NPs followed by that of B. coagulans. The intervention with B. coagulans was found to reduce the inflammatory response and oxidative stress. A 16S rDNA sequencing analysis revealed that B. coagulans had increased the diversity of gut microbiota and optimized the composition of gut microbiota. Fecal metabolomics analysis indicated that B. coagulans had restored the homeostasis of sphingolipids and amino acid metabolism. The intervention strategy of administering TiO2 NPs followed by B. coagulans was found to be more effective. In conclusion, B. coagulans could alleviate intestinal damage induced by TiO2 NPs in high-fat-diet mice TiO2B. coagulans. Our results suggest a new avenue for interventions against intestinal damage induced by TiO2 NPs.
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Oral static biofilm model is an important tool for in vitro simulation of oral microecological environment, which has become an important method for studying the pathogenesis of various oral diseases and testing the efficacy of various drugs, oral care products and foods due to its low cost, high throughput, good reliability and easy operation. The establishment of oral static biofilm models allows the selection of different devices, inoculum sources, media, substrates and culture conditions according to the purpose of the study, and the evaluation of biofilm growth by various methods such as measuring biomass, metabolic activity, community structure and performing visualization analysis. This paper summarizes the methodological elements reported in recent years for the establishment and evaluation of oral static biofilm models, and analyzes and discusses the applicability of various methods in the hope of contributing to the research and production practice in related fields.
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Biofilmes , Reprodutibilidade dos TestesRESUMO
Exposure to titanium dioxide nanoparticles (TiO2 NPs) and bisphenol A (BPA) is ubiquitous, especially through dietary and other environmental pathways. In the present study, adult C57BL/6J mice were exposed to TiO2 NPs (100 mg/kg), BPA (0, 5, and 50 mg/kg), or their binary mixtures for 13 weeks. The 16S rDNA amplification sequence analysis revealed that co-exposure to TiO2 NPs and BPA altered the intestinal microbiota; however, this alteration was mainly caused by TiO2 NPs. Faecal metabolomics analysis revealed that 28 metabolites and 3 metabolic pathways were altered in the co-exposed group. This study is the first to reveal the combined effects of TiO2 NPs and BPA on the mammalian gut microbial community and metabolism dynamics, which is of great value to human health. The coexistence of TiO2 NPs and BPA in the gut poses a potential health risk due to their interaction with the gut microbiota.
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The traditional methods for detection of Staphylococcus aureus in food have some shortcomings, such as fussy operation and dependence on separation of pure colony. A novel strategy for detection of pathogenic bacteria bases on targeted analysis of the characteristic peptides by LC-MS/MS. The key to the success of this strategy is to identify a combination of reliable characteristic peptides that afford high specificity. In this study, the candidate characteristic peptides of S. aureus were evaluated bioformatically and then verified experimentally. UniProt protein database were used to perform BLAST analysis on the candidate characteristic peptides, and then their specificity were compared via targeted analysis in S. aureus and other Staphylococcus strains by LC-MS/MS. Finally, suitable S. aureus characteristic peptide was determined, by using which 100 cfu/mL S. aureus in milk samples were successfully detected, meeting the detection limit requirement in actual application. The results demonstrated the feasibility of the detection strategy of S. aureus based on characteristic peptides. The exploratory work is expected to promote the methodology research of food-borne pathogen inspection and further improve the inspection efficiency and quality.
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Infecções Estafilocócicas , Staphylococcus aureus , Cromatografia Líquida , Humanos , Peptídeos , Infecções Estafilocócicas/diagnóstico , Espectrometria de Massas em TandemRESUMO
Many bacteria metabolize aromatic compounds via catechol as a catabolic intermediate, and possess multiple genes or clusters encoding catechol-cleavage enzymes. The presence of multiple isozyme-encoding genes is a widespread phenomenon that seems to give the carrying strains a selective advantage in the natural environment over those with only a single copy. In the naphthalene-degrading strain Pseudomonas putida ND6, catechol can be converted into intermediates of the tricarboxylic acid cycle via either the ortho- or meta-cleavage pathways. In this study, we demonstrated that the catechol ortho-cleavage pathway genes (catBICIAI and catBIICIIAII) on the chromosome play an important role. The catI and catII operons are co-transcribed, whereas catAI and catAII are under independent transcriptional regulation. We examined the binding of regulatory proteins to promoters. In the presence of cis-cis-muconate, a well-studied inducer of the cat gene cluster, CatRI and CatRII occupy an additional downstream site, designated as the activation binding site. Notably, CatRI binds to both the catI and catII promoters with high affinity, while CatRII binds weakly. This is likely caused by a T to G mutation in the G/T-N11-A motif. Specifically, we found that CatRI and CatRII regulate catBICIAI and catBIICIIAII in a cooperative manner, which provides new insights into naphthalene degradation.
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Proteínas de Bactérias/metabolismo , Catecóis/metabolismo , Pseudomonas putida/metabolismo , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Família Multigênica , Óperon , Regiões Promotoras Genéticas , Pseudomonas putida/genéticaRESUMO
Nostoc flagelliforme is an edible cyanobacterium with excellent food and herbal values. It has been used as food in China for more than 2000 years. Many studies have been focused on improving the yield and bioactivity of Nostoc flagelliforme polysaccharides although these have ignored the functional properties. In this study, we extracted and purified three polysaccharides (WL-CPS, NaCl-CPS and Glu-CPS) from Nostoc flagelliforme under normal, salt stress and mixotrophic culture conditions, respectively, in order to change the physicochemical properties of polysaccharides with the aim of obtaining better functional properties. Both salt stress and mixotrophic culture conditions increased the specific yield of polysaccharides. Their functional properties were comparatively investigated and the results showed that NaCl-CPS exhibited the highest emulsification activity and flocculation capability, which was also higher than that of some commercial products. In contrast, Glu-CPS exhibited the highest water and oil holding capacities, foaming property, intrinsic viscosity and bile acids binding capacity. Our results indicated that both NaCl-CPS and Glu-CPS could be considered to be functional polysaccharides according to their respective characteristics, which have great potential in numerous applications, such as food, pharmaceutical, cosmetic, chemical and mineral industries. These findings also demonstrated the potential application of the proper regulation of culture conditions in the development of polysaccharides with desired functional properties.
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Increasing attention has been paid to the toxicity and hazards of antibiotics on non-target organisms in soil ecosystems because redundant antibiotics in the excretion of treated animals are being brought into the soil by way of manure and sewage irrigation. In order to understand the toxic mechanisms of antibiotics in soil ecosystems, the earthworm Eisenia fetida was exposed to 500 mg kg-1 of oxytetracycline (OTC) as a typical antibiotic for 7, 14 and 21 days. The total proteins of E. fetida in each treatment were separated by two-dimensional gel electrophoresis and differential expressed proteins were identified by MALDI-TOF/TOF-MS. A total of 30 proteins were successfully identified and divided into four categories based on the function. It was surprisingly found that more than 50% of identified proteins belong to the actin family, and all of them were down-regulated more than 2.0-fold. In the meantime, the fibrinolytic enzymes, an important protease with plasminogen activator activity, were suppressed in the last two weeks. The validations in the mRNA level were performed using RT-PCR. However, due to the incomplete genome sequence of E. fetida, we failed to identify more proteins response to OTC stress. This study may provide a new insight into the discovery of novel biomarkers for continuous-poured and low-toxicity pollutants.
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The activated sludge process can effectively remove polycyclic aromatic hydrocarbons (PAHs) from wastewater via biodegradation. However, the degradable microorganisms and functional enzymes involved in this process remain unclear. In this study, we successfully employed a laboratory-scale sequential batch reactor to investigate variations in microbial community and protein expression in response to the addition of different PAHs and process time. The analysis of bacterial community structure by 454 pyrosequencing of the 16S rRNA gene indicated that bacteria from Burkholderiales order were dominant in PAHs treated sludge. Mass spectrometry performed with 2D protein profiles of all sludge samples demonstrated that most proteins exhibiting differential expression profiles during the process were derived from Burkholderiales populations; these proteins are involved in DNA replication, fatty acid and glucose metabolism, stress response, protein synthesis, and aromatic hydrocarbon metabolism. Nevertheless, the protein expression profiles indicated that naphthalene, but not anthracene, can induce the expression of PAH-degrading proteins and accelerate its elimination from sludge. Though only naphthalene and anthracene were added into our experimental groups, the differentially expressed enzymes involved in other PAHs (especially biphenyl) metabolism were also detected. This study provides apparent evidence linking the metabolic activities of Burkholderiales populations with the degradation of PAHs in activated sludge processes. Overall, our findings highlighted the successful application of metaproteomics integrated with microbial diversity analysis by high-throughput sequencing technique on the analysis of environmental samples, which could provide a convenience to monitor the changes in proteins expression profiles and their correlation with microbial diversity.
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Background: Although the functional redundancy of catechol 1,2-dioxygenase (C12O) genes has been reported in several microorganisms, limited enzymes were characterised, let alone the advantage of the coexistence of the multiple copies of C12O genes. Results: In this study, four novel C12O genes, designated catA, catAI, catAII and catAIII, in the naphthalene-degrading strain Pseudomonas putida ND6, were cloned and characterised. Phylogenetic analysis of their deduced amino acid sequences revealed that the four C12O isozymes each formed independent subtrees, together with homologues from other organisms. All four enzymes exhibited maximum activity at pH 7.4 and higher activity in alkaline than in acidic conditions. Furthermore, CatA, CatAI and CatAIII were maximally active at a temperature of 45°C, whereas a higher optimum temperature was observed for CatAII at a temperature of 50°C. CatAI exhibited superior temperature stability compared with the other three C12O isozymes, and kinetic analysis indicated similar enzyme activities for CatA, CatAI and CatAII, whereas that of CatAIII was lower. Significantly, among metal ions tested, only Cu2+ substantially inhibited the activity of these C12O isozymes, thus indicating that they have potential to facilitate bioremediation in environments polluted with aromatics in the presence of metals. Moreover, gene expression analysis at the mRNA level and determination of enzyme activity clearly indicated that the redundancy of the catA genes has increased the levels of C12O. Conclusion: The results clearly imply that the redundancy of catA genes increases the available amount of C12O in P. putida ND6, which would be beneficial for survival in challenging environments.
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Pseudomonas putida/enzimologia , Pseudomonas putida/genética , Catecol 1,2-Dioxigenase/genética , Temperatura , Biodegradação Ambiental , Clonagem Molecular , Catecol 1,2-Dioxigenase/análise , Catecol 1,2-Dioxigenase/metabolismo , Genes Bacterianos , Concentração de Íons de Hidrogênio , Isoenzimas , MetaisRESUMO
Enhanced ecological floating beds were implemented to reduce nutrient quantity and improve the water quality of a eutrophic lake. The results showed that average removal efficiencies of CODCr, total nitrogen, NH3-N and total phosphorus for Canna indica L. set-up were 23.1%, 15.3%, 18.1% and 19.4% higher, respectively, than that of the setup with only substrate, and 14.2%, 12.8%, 7.9% and 11.9% higher than Iris pseudacorus L. ecological floating bed. The microbial community structure had obvious differences between devices and low similarity; bacteria were mainly attached on the fiber filling. The microbial population was abundant at the start and end of the experiment. Shannon index of samples selected ranged from 0.85 to 1.05. The sequencing results showed that fiber filling collected most uncultured bacteria species and the majority of bacteria on the plant roots were ß-Proteobacteria and α-Proteobacteria. The co-dominant species attaching to the filling and plant was Nitrosomonadaceae.
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Ecologia , Eutrofização , Proteobactérias/metabolismo , Purificação da Água/instrumentação , Purificação da Água/métodos , Biodiversidade , Análise da Demanda Biológica de Oxigênio , Eletroforese em Gel de Gradiente Desnaturante , Lagos , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Filogenia , Desenvolvimento Vegetal , Reação em Cadeia da Polimerase , Água/químicaRESUMO
Biofilm is a significant cause for membrane fouling. Antibacterial-coated surfaces can inhibit biofilm formation by killing bacteria. In this study, polyethersulfone (PES) microfiltration membrane was photografted by four antibiotic quaternary ammonium compounds (QACs) separately, which were synthesized from dimethylaminoethyl methacrylate (DMAEMA) by quaternization with butyl bromide (BB), octyl bromide (OB), dodecyl bromide (DB), or hexadecyl bromide (HB). XPS, ATR-FTIR, and SEM were used to confirm the surfaces' composition and morphology. After modification, the pores on PES-g-DMAEMA-BB and PES-g-DMAEMA-OB were blocked, while PES-g-DMAEMA-DB and PES-g-DMAEMA-HB were retained. We supposed that DMAEMA-BB and DMAEMA-OB aggregated on the membrane surface due to the activities of intermolecular or intramolecular hydrogen bonds. Bacteria testing found the antibacterial activities of the membranes increased with the length of the substituted alkyl chain. Correspondingly, little bacteria were observed on PES-g-DMAEMA-DB and PES-g-DMAEMA-HB by SEM. The antifouling properties were investigated by filtration of a solution of Escherichia coli. Compared with the initial membrane, PES-g-DMAEMA-DB and PES-g-DMAEMA-HB showed excellent anti-biofouling performance with higher relative flux recovery (RFR) of 88.3% and 92.7%, respectively. Thus, surface functionalization of the PES membrane with QACs can prevent bacteria adhesion and improve the anti-biofouling activity by the contact-active antibacterial property.
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OBJECTIVE: To investigate whether genes other than the operons nahAaAbAcAdBFCED and nahGTHINLOMKJ of Pseudomonas putida are involved in the tolerance of the bacterium to naphthalene. RESULTS: Cellular responses of P. putida ND6 grown with 2 and 4 g naphthalene/l were investigated using a quantitative proteomic-based approach. Comparative analysis of the proteome data identified that the expression levels of 22 proteins involved in heat shock and universal stress response, naphthalene degradation, cell envelope synthesis, and motility were up-regulated; while the expression levels of 26 proteins involved in protein and fatty acid synthesis, carbon compound, nucleotide, and amino acid metabolism, and small molecule transport were down-regulated. CONCLUSION: Our findings offer insights into the cellular response of P. putida to high naphthalene concentrations at the protein level.
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Proteínas de Bactérias/análise , Tolerância a Medicamentos , Naftalenos/toxicidade , Proteoma/análise , Pseudomonas putida/química , Pseudomonas putida/efeitos dos fármacos , Citosol/química , Ácidos Graxos/análise , Estresse FisiológicoRESUMO
BACKGROUND: Matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) is emerging as a rapid and accurate tool for identifying pathogens. MALDI-TOF identification of Candida at the species level remains unsatisfactory because of an incomplete commercial database. METHODS: Using Bruker Daltonics MALDI Biotyper software, an in-house spectral database library was created with m/z ratios of 2,000 to 20,000 Da from 60 successfully identified clinical isolates of Candida spp. (6 species). It was incorporated into the original database to produce the augmented Bruker-Tianjin database. The augmented database was tested with 347 clinical isolates of 6 species comparing with Bruker database in parallel. RESULTS: The identification rates at the species level were 91.6% (318/347) using the Bruker database and 99.1% (344/347) for the Bruker-Tianjin database. CONCLUSIONS: Database expansion and refinement can easily and effectively improve MALDI-TOF MS performance for enhanced clinical pathogen identification.
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Candida/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Candida/classificação , Análise por Conglomerados , Reação em Cadeia da Polimerase , Especificidade da EspécieRESUMO
OBJECTIVE: To establish the mass spectrometry database of Salmonella species by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. METHODS: By use of standard stains representing 21 species of Salmonella, a reference database was established MALDI-TOF-MS-based species identification. The profiles of colonies in the identical culture condition with different times were analysed for each of standard strains. To evaluate the database, 200 blind-coded isolates were tested by the established database and the original database. RESULTS: The positive rate of identification by the original database, the established database and conbine-database were 87.5%, 97.0% and 97.5%. 21 Salmonella strains were divided into 3 types by MALDI-TOF-MS at distance level of 500. PCA of the reference strains showed difference between them. There were little changes of mass spectrometric data of several strains in different culture condition. CONCLUSION: The established database could expand the original one and be used for identification of Salmonella species. The strategy may be fit for other bacteria.
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Técnicas de Tipagem Bacteriana/métodos , Bases de Dados Factuais , Salmonella/classificação , Salmonella/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Especificidade da EspécieRESUMO
Laminectomy is a widely accepted treatment for lumbar disorders. Epidural Fibrosis (EF) is a common post-laminectomy or post-discectomy complication, which is thought to cause recurrent pain. RNA interference (RNAi) is a process by which double-stranded RNA triggers the destruction of mRNAs sharing the same sequence. Previously, extra-cellular signal-regulated kinase (ERK) 2 plays crucial roles in suppressing the collagen expression. To investigate the effects of lentiviral ERK2 siRNA on the prevention of post-laminectomy EF formation in a rat model, a controlled double-blinded study was conducted in 75 healthy adult Wistar rats that underwent laminectomy. They were divided randomly into 3 groups according to the treatment method: (1) control group; (2) ERK scrRNA group; (3) ERK siRNA group. All rats were euthanized humanely 4 weeks post-laminectomy. The hydroxyproline content, Rydell score, vimentin cells density, fibroblasts density, inflammatory cells density and inflammatory factors expressions were performed. The hydroxyproline content, Rydell score, vimentin cells density, fibroblasts density, inflammatory cells density and inflammatory factors expressions all suggested better results in ERK siRNA group than other two groups. None of the rats expired and no obvious adverse effects were observed. Local delivery of a lentiviral siRNA targeting ERK2 can prevent epidural scar adhesion in post-laminectomy rat via inhibiting collagen expression and inflammation.