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1.
Medicine (Baltimore) ; 99(12): e18930, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32195925

RESUMO

BACKGROUND: Lumbar disc herniation (LDH) is a common disease that seriously affects patients' quality of life. Although several articles have reported that acupuncture can improve the symptoms of LDH, different guidelines do not evaluate the efficacy of acupuncture consistently, new randomized controlled trials have been published in recent years.The purpose of this study is to evaluate the efficacy and safety of acupuncture for LDH. METHOD: Electronic resource databases, trial registration platform, and different types of grey literature will be systematically searched for eligible studies by 2 authors independently. The type of trial will be limited to randomized controlled trials on acupuncture treatment for LDH. Search strategy will be a combination of terms associated with LDH (eg, low back pain or sciatica) and study of design (eg, randomized controlled trials or clinical trial). Data from homogeneous studies will be combined in a fixed-effects model, and the evidence level will be measured by grading of recommendations assessment, development, and evaluation. RESULTS: This study will provide high-quality evidence to evaluate the relief of pain intensity and improvement of dysfunction of acupuncture in patients with LDH, and to evaluate the safety of acupuncture. CONCLUSION: This study will provide strong evidence for evaluating whether acupuncture therapy is effective and safe for LDH patients. PROSPERO REGISTRATION NUMBER: CRD 42019137399.

2.
Microbiology ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32209171

RESUMO

The oleaginous fungus Mortierella alpina can synthesize a variety of polyunsaturated fatty acids, which are used extensively in industry for the production of arachidonic acid (AA). NADPH is the limiting factor and critical reducing agent in lipid biosynthesis. In the folate cycle, methylenetetrahydrofolate dehydrogenase (MTHFDL) catalyzes the conversion of methylene tetrahydrofolate into 10-formyl-tetrahydrofolate with the reduction of NADP+ to NADPH. MTHFDL RNAi was used to investigate the role of the folate cycle in lipogenesis. Gene knockdown decreased the transcript levels of MTHFDL by about 50 % and attenuated cell fatty acid synthesis. The observation of decreased NADPH levels and downregulated NADPH-producing genes in response to MTHFDL RNAi indicates a novel aspect of the NADPH regulatory mechanism. Thus, our study demonstrates that MTHFDL plays key role in the mediation of NADPH in lipogenesis in M. alpina.

3.
J Dairy Sci ; 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32113760

RESUMO

Fermented dairy products have been recognized as the best carriers for the administration of probiotics. Because one of the potential probiotic strains, Lactobacillus plantarum, has poor proteolytic ability and weak acidifying capacity in milk fermentation, the aim of this study was to preliminarily investigate the stimulation effect of plant-based meals on L. plantarum CCFM8661 growth in milk, and subsequently develop a yogurt or yogurt drinks containing probiotic strain L. plantarum CCFM8661. Milk supplemented with different concentrations (5 to 10%, wt/wt) of oat extract and malt extract, inoculated with 2.5 × 107 cfu/mL of L. plantarum CCFM8661, and then incubated at 35°C. The pH value, titration acidity, and viable cell counts during 48-h fermentation at 35°C and 25-d storage at 4°C, were determined at different intervals. The results showed that the promotion effects of oat extract and malt extract on L. plantarum CCFM8661 growth rate in milk were much stronger than almond, walnut, sweet corn, peanut, and soybean meals. In addition, the stimulation effect of oat extract was associated with its concentration, and was much stronger than that of malt extract. Furthermore, viable counts and titration acidity of yogurt were gradually increased in the oat extract group, whereas viable counts were gradually decreased and titration acidity were slightly increased in the malt extract group during the 25-d storage at 4°C.

4.
Food Chem ; 317: 126447, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32092610

RESUMO

The inhibitory effect of caffeic acid on the formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine (PhIP) was investigated in chemical model systems under microwave heating (MW). A mechanistic study was subsequently carried out to identify the inhibitory mechanism. The results showed that both for conductive heating (CV) and MW, the inhibition of PhIP increased with the concentration of caffeic acid but decreased with the prolongation of heating time. The inhibition on PhIP under MW was always higher than under CV, which were dominated by the difference in dielectric loss (ε″). UPLC-MS analysis showed that caffeic acid releases a CO2 molecule to produce 4-vinylcatechol which can form adducts with phenylacetaldehyde, thus reducing its availability for PhIP formation. The structure of adduct was characterized as 3-(3,4-dihydroxyphenyl)-2-phenylbutanal with a molecular weight of 256. The findings indicate that trapping of phenylacetaldehyde by 4-vinylcatechol is a key mechanism of caffeic acid in inhibiting PhIP formation.

5.
Molecules ; 25(3)2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32046080

RESUMO

Alkali was used to adjust the pH and neutralize the excess acids of dough in the processing of Chinese northern steamed bread (CNSB). However, extra alkali addition generally resulted in alkalic flavor and poor appearance. The aim of this work was to investigate the role of proofed dough pH on the texture of CNSB. Correlation analysis demonstrated that the pH value of proofed dough has a significant effect on the textural properties of CNSB. The mechanism studies found that gradual acidification of dough by lactic acid bacteria is a critical factor affecting the process. Conversely, chemical acidification weakened the texture property of products and reduced the dough rheology. Scanning electron microscope (SEM) analysis showed that fermentation with starter for 12 h produced a continuous and extensional protein network in the proofed dough. Furthermore, the decreasing pH of proofed dough increased the extractability of protein in a sodium dodecyl sulfate (SDS)-containing medium and the content of free sulfhydryl (SH). The structure and content of gluten, especially influenced by gradual acidification level, change the quality of the final product. It is a novel approach to obtain an alkali-free CNSB with excellent quality by moderate gluten adjustment.

6.
BMC Genomics ; 21(1): 119, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32013858

RESUMO

BACKGROUND: Lactobacillus gasseri as a probiotic has history of safe consumption is prevalent in infants and adults gut microbiota to maintain gut homeostasis. RESULTS: In this study, to explore the genomic diversity and mine potential probiotic characteristics of L. gasseri, 92 strains of L. gasseri were isolated from Chinese human feces and identified based on 16 s rDNA sequencing, after draft genomes sequencing, further average nucleotide identity (ANI) value and phylogenetic analysis reclassified them as L. paragasseri (n = 79) and L. gasseri (n = 13), respectively. Their pan/core-genomes were determined, revealing that L. paragasseri had an open pan-genome. Comparative analysis was carried out to identify genetic features, and the results indicated that 39 strains of L. paragasseri harboured Type II-A CRISPR-Cas system while 12 strains of L. gasseri contained Type I-E and II-A CRISPR-Cas systems. Bacteriocin operons and the number of carbohydrate-active enzymes were significantly different between the two species. CONCLUSIONS: This is the first time to study pan/core-genome of L. gasseri and L. paragasseri, and compare their genetic diversity, and all the results provided better understating on genetics of the two species.

7.
Environ Pollut ; 261: 114164, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32088434

RESUMO

Di-(2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer, which can enter the body through a variety of ways and exerted multiple harmful effects, including liver toxicity, reproductive toxicity and even glucose metabolism disorder. Many studies have suggested that changes of gut microbiota are closely related to the occurrence of various diseases, but the effects of DEHP exposure on gut microbiota are still unclear. It was found in this study that the damage to different tissues by DEHP on two strains each from two different species of male rodents before puberty was dose and time of exposure dependent, and also depending on the strain and species of rodent. Sprague-Dawley (SD) rats showed highest sensitivity to DEHP exposure, with most severe organ damage, highest Th1 inflammatory response and most significant body weight gain. Correspondingly, the gut microbiota of SD rats showed most significant changes after DEHP exposure. Only SD rats, but not Wistar rats, BALB/c and C57BL/6J mice showed an increase in Firmicutes/Bacteroidetes ratio and Proteobacteria abundance in the fecal samples, which are known to associate with obesity and diabetes. This is consistent with the increasing body weight gain which was only found in SD rats. In addition, the decrease in the level of butyrate, increase in the abundance of potential pathogens and microbial genes linked to colorectal cancer, Parkinson's disease, and type 2 diabetes in the SD rats were associated with issue and functional damages and Th1 inflammatory response caused by DEHP exposure. We postulate that the differential effects of DEHP on gut microbiota may be an important cause of the differences in the toxicity on different strains and species of rodents to DEHP.

8.
Microb Cell Fact ; 19(1): 23, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024520

RESUMO

The gut microbiota can significantly affect the function of the intestinal barrier. Some intestinal probiotics (such as Lactobacillus, Bifidobacteria, a few Escherichia coli strains, and a new generation of probiotics including Bacteroides thetaiotaomicron and Akkermansia muciniphila) can maintain intestinal epithelial homeostasis and promote health. This review first summarizes probiotics' regulation of the intestinal epithelium via their surface compounds. Surface layer proteins, flagella, pili and capsular polysaccharides constitute microbial-associated molecular patterns and specifically bind to pattern recognition receptors, which can regulate signaling pathways to produce cytokines or inhibit apoptosis, thereby attenuating inflammation and enhancing the function of the gut epithelium. The review also explains the effects of metabolites (such as secreted proteins, organic acids, indole, extracellular vesicles and bacteriocins) of probiotics on host receptors and the mechanisms by which these metabolites regulate gut epithelial barrier function. Previous reviews summarized the role of the surface macromolecules or metabolites of gut microbes (including both probiotics and pathogens) in human health. However, these reviews were mostly focused on the interactions between these substances and the intestinal mucosal immune system. In the current review, we only focused on probiotics and discussed the molecular interaction between these bacteria and the gut epithelial barrier.

9.
Clin Nutr ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-32005532

RESUMO

BACKGROUND & AIMS: Clinical trials have reported controversial results regarding the effectiveness of probiotics in alleviating functional constipation in adults. We reviewed relevant randomized controlled trials to elucidate the effectiveness of probiotics on constipation symptoms in adults with functional constipation. METHODS: We searched Medline, the Cochrane Library, Web of Science, and Google Scholar for relevant articles published up to April 2019. The primary outcomes of interest were stool frequency, gut transit time (GTT), stool consistency, and bloating. Two authors independently performed the study selection, risk-of-bias assessment, and data extraction. The outcome data were extracted from each included study and synthesized using weighted mean differences (WMDs) or standardized mean differences (SMDs). Pooled data synthesis was performed using a random-effects model. RESULTS: In total, 2327 relevant studies were identified, 15 of which were found to be eligible randomized controlled trials and were included in the meta-analysis. Pooling of the extracted data demonstrated that probiotic consumption significantly reduced the whole GTT by 13.75 h [95% confidence interval (CI): -21.93 to -5.56 h] and increased the stool frequency by 0.98 (95% CI: 0.36 to 1.60) bowel movements per week. This increase was significant with the consumption of multispecies probiotics [at least two bacteria; WMD: 1.22 (95% CI: 0.50 to 1.94) bowel movements per week] but not with the consumption of Bifidobacterium lactis [WMD: 1.34 (95% CI: -0.27 to 2.94) bowel movements per week] or B. longum [WMD: -0.02 (95% CI: -0.56 to 0.53) bowel movements per week] alone. Multispecies probiotics (WMD: 1.37; 95% CI: 0.72 to 2.01), but not single-species probiotics (WMD: 1.18; 95% CI: -0.59 to 2.96), improved stool consistency (WMD: 1.30; 95% CI: 0.22 to 2.38). Similarly, multispecies probiotics (at least two bacteria; WMD: -0.49; 95% CI: -0.85 to -0.13), but not single-species probiotics (WMD: -0.24; 95% CI: -0.55 to 0.07), significantly decreased bloating. Performance bias were high, whereas detection bias was unclear because of inadequate reporting. CONCLUSION: Consumption of probiotics, in particular, multispecies probiotics, may substantially reduce the GTT, increase the stool frequency, and improve the stool consistency. Thus, probiotics can be regarded as safe and natural agents for alleviation of functional constipation in adults.

10.
Zhongguo Zhen Jiu ; 40(2): 217-20, 2020 Feb 12.
Artigo em Chinês | MEDLINE | ID: mdl-32100512

RESUMO

Malignant pleural effusion (MPE) is one of the common complications of tumor. Acupuncture-moxibustion therapy has several advantages for treatment of MPE. Acupuncture is regarded as a complex individualized intervention, and its characteristics of TCM is difficult to be reflected by strict randomized controlled trials. The registry study provides more possibilities for the data collection of individualized diagnosis and treatment under the guidance of the overall concept and syndrome differentiation, and is more suitable for data management and collection of large samples and multi-center trials in the real-world study. It has become an opportunity to carry out real-world study of acupuncture for MPE. There are many challenges in the registry study of acupuncture for MPE. However, it is of great significance to collect real-world data of acupuncture for MPE to improve the clinical effect of MPE and provide a new clinical research method for acupuncture in tumors and related complications.


Assuntos
Terapia por Acupuntura , Moxibustão , Derrame Pleural Maligno/terapia , Sistema de Registros , Humanos , Medicina Tradicional Chinesa , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Sci Rep ; 10(1): 2922, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075992

RESUMO

Many Caribbean coral reefs are heavily degraded, yet their pre-human, natural states are often assumed or estimated using space-for-time substitution approaches. Here we use an 11-hectare suite of fossilised mid-Holocene (7.2-5.6 ka) fringing reefs in Caribbean Panama to define natural variation in hard coral community structure before human-impact to provide context to the states of the same reefs today. We collected bulk samples from four trenches dug into the mid-Holocene fossil reef and surficial bulk samples from 2-10 m depths on five adjacent modern reefs extending over 5 km. Analysis of the abundances of coral taxa in fossil bulk samples define the Historical Range of Variation (HRV) in community structure of the reefs. When compared to the community structure of adjacent modern reefs, we find that most coral communities today fall outside the HRV, identifying them as novel ecosystems and corroborating the well-documented transition from acroporid-dominated Caribbean reefs to reefs dominated by stress-tolerant taxa (Porites and Agaricia). We find one modern reef, however, whose community composition remains within the HRV showing that it has not transitioned to a novel state. Reef-matrix cores extracted from this reef reveal that the coral community has remained in this state for over 800 years, suggesting long-term stability and resistance to the region-wide shift to novel states. Without these data to provide historical context, this potentially robust and stable reef would be overlooked since it does not fulfil expectations of what a Caribbean coral reef should look like in the absence of humans. This example illustrates how defining past variation using the fossil record can improve our understanding of modern degradation and guide conservation.

12.
Microbiol Res ; 233: 126409, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31927503

RESUMO

Insomnia is a common health problem in modern societies. GABA, an inhibitory neurotransmitter, can promote relaxation and reduce anxiety. In this study, milk was fermented with Lactobacillus brevis DL1-11, a strain with high GABA-producing capacity. The potential beneficial effects of this fermented milk on anxiety and sleep quality were evaluated in animal experiments. Sixty mice were divided into control, non-GABA fermented milk (NGFM), low-dose GABA fermented milk (LGFM, 8.83 mg/kg.bw), medium-dose GABA fermented milk (MGFM, 16.67 mg/kg.bw), high-dose GABA fermented milk (HGFM, 33.33 mg/kg.bw) and diazepam groups. The results of open field test and elevated plus-maze test indicated decreases in anxiety behavior after oral HGFM administration. Moreover, mice in the HGFM group exhibited a significantly prolonged sleep time after an intraperitoneal injection of sodium pentobarbital and a shortened sleep latency after an intraperitoneal injection of sodium barbital. These results indicate a beneficial effect of HGFM on sleep. Additionally, significant increases in the relative abundances of Ruminococcus, Adlercreutzia and Allobaculum and the levels of some short-chain fatty acids (SCFAs), such as butyric acid, were observed in the HGFM group. The results suggest that GABA-fermented milk may improve sleep and the protective pathways may involve in regulation of gut microbiota and increase of SCFAs level.

13.
Food Funct ; 11(1): 221-235, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31915776

RESUMO

Lactobacillus salivarius is a species of lactic acid bacteria with probiotic potency. Compared to such well-known probiotics as L. rhamnosus and L. casei, the genomic characteristics and health-beneficial effects of L. salivarius are inadequately researched. For this study, a medium with enhanced selectivity for the isolation of L. salivarius was developed by optimizing the carbon source and antibiotics in the medium. Seventy-three L. salivarius strains were isolated from 472 fecal samples from Chinese populations, and their pan-genomic and phylogenetic characterizations were analyzed. Three strains (L. salivarius HN26-4, NT4-8, and FXJCJ7-2) that were clearly categorized in different sub-phylotypes of the phylogenetic tree were randomly selected for further studies. Compared to the other two tested strains, L. salivarius FXJCJ7-2 showed higher tolerance to simulated gastrointestinal tract conditions and more significant anti-inflammatory effects in lipopolysaccharides (LPS)-treated RAW264.7 murine macrophages. This strain was also more effective in reversing LPS-induced alterations in gut barrier function, colonic histopathology, Treg/Th-17 balance, immunomodulatory indicators, nuclear factor kappa B pathway activation, and the intestinal microenvironment of the mice than the other two tested strains. Comparative genomic analysis indicated that these protective effects may be related to the specific genes of L. salivarius FXJCJ7-2 that were involved in the tolerance to the gastrointestinal environment, short-chain fatty acid production, and host-bacterium interaction.

14.
Genes (Basel) ; 11(1)2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936280

RESUMO

Lactobacillus ruminis is a commensal motile lactic acid bacterium living in the intestinal tract of humans and animals. Although a few genomes of L. ruminis were published, most of them were animal derived. To explore the genetic diversity and potential niche-specific adaptation changes of L. ruminis, in the current work, draft genomes of 81 L. ruminis strains isolated from human, bovine, piglet, and other animals were sequenced, and comparative genomic analysis was performed. The genome size and GC content of L. ruminis on average were 2.16 Mb and 43.65%, respectively. Both the origin and the sampling distance of these strains had a great influence on the phylogenetic relationship. For carbohydrate utilization, the human-derived L. ruminis strains had a higher consistency in the utilization of carbon source compared to the animal-derived strains. L. ruminis mainly increased the competitiveness of niches by producing class II bacteriocins. The type of clustered regularly interspaced short palindromic repeats /CRISPR-associated (CRISPR/Cas) system presented in L. ruminis was mainly subtype IIA. The diversity of CRISPR/Cas locus depended on the high denaturation of spacer number and sequence, although cas1 protein was relatively conservative. The genetic differences in those newly sequenced L. ruminis strains highlighted the gene gains and losses attributed to niche adaptations.

15.
Genes (Basel) ; 11(1)2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31947593

RESUMO

The potential probiotic benefits of Lactobacillus mucosae have received increasing attention. To investigate the genetic diversity of L. mucosae, comparative genomic analyses of 93 strains isolated from different niches (human and animal gut, human vagina, etc.) and eight strains of published genomes were conducted. The results showed that the core genome of L. mucosae mainly encoded translation and transcription, amino acid biosynthesis, sugar metabolism, and defense function while the pan-genomic curve tended to be close. The genetic diversity of L. mucosae mainly reflected in carbohydrate metabolism and immune/competitive-related factors, such as exopolysaccharide (EPS), enterolysin A, and clustered regularly interspaced short palindromic repeats (CRISPR)-Cas. It was worth noting that this research firstly predicted the complete EPS operon shared among L. mucosae. Additionally, the type IIIA CRISPR-Cas system was discovered in L. mucosae for the first time. This work provided new ideas for the study of this species.

16.
Food Funct ; 11(2): 1279-1291, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31984399

RESUMO

Lactobacillus plantarum is a probiotic that is widely used to prevent ulcerative colitis (UC). However, the effects of this species are strain-specific. We believe that the physiological characteristics of L. plantarum strains may affect their UC-alleviating function. Therefore, this study investigated the relationship between the alleviating effect of L. plantarum strains on UC and their physiological characteristics in vitro. The physiological characteristics of 14 L. plantarum strains were assayed in vitro, including gastrointestinal transit tolerance, oligosaccharide fermentation, HT-29 cell adhesion, generation time, exopolysaccharide production, acetic acid production, and conjugated linoleic acid (CLA) synthesis. To create animal models, colitis was established in C57BL/6 mice by adding 3.5% dextran sulfate sodium to drinking water for 7 days. L. plantarum strains with significantly different physiological characteristics were orally administered to the mice at a dose of 3 × 109 CFU. The results indicated that among the tested L. plantarum strains, L. plantarum N13 and L. plantarum CCFM8610 significantly alleviated colitis in the mice, as observed from the restoration of the body weight and disease activity index (DAI) score, recovery of the gut microbiota composition, reduced expression of pro-inflammatory cytokines, and significantly inhibited expression of p65. Correlation analysis indicated that four of the measured physiological characteristics (gastrointestinal transit tolerance, HT-29 cell adhesion, generation time, and CLA synthesis) were related to the UC-alleviating effects to different degrees. The strongest correlation was observed between the CLA synthesis ability and UC-alleviating effects (with Pearson correlation coefficients for IL-1ß, IL-6, IL-17F, TNF-α, myeloperoxidase, and the DAI all below -0.95). The ability to synthesize CLA may be the key physiological characteristic of L. plantarum in UC alleviation. Our findings may contribute to the rapid screening of lactic acid bacterial strains with UC-alleviating effects.

17.
Food Chem Toxicol ; 135: 110934, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31682931

RESUMO

The novel commensal strain of Bacteroides fragilis HCK-B3 isolated from a healthy Chinese donor was discovered beneficial effects of attenuating lipopolysaccharides-induced inflammation. In order to contribute to the development of natural next-generation probiotic strains, the safety assessment was carried out with in vitro investigations of its morphology, potential virulence genes and antimicrobial resistance, and an in vivo acute toxicity study based on both healthy and immunosuppressed mice by cyclophosphamide injection. Consequently, the potential virulence genes in the genome of B. fragilis HCK-B3 have yet been identified as toxicity-associated. The absence of plasmids prevents the possibility of transferring antibiotic resistance features to other intestinal commensals. No intracorporal pathogenic properties were observed according to the body weight, hematological and liver parameters, cytokine secretions and tissue integrity. In addition, B. fragilis HCK-B3 performed alleviations on part of the side effects caused by the cyclophosphamide treatment. Thus, the novel strain of B. fragilis HCK-B3 was confirmed to be non-toxigenic and did not display adverse effects in both healthy and immune-deficient mice at a routinely applicable dose.


Assuntos
Bacteroides fragilis/patogenicidade , Probióticos/toxicidade , Animais , Antibacterianos/farmacologia , Bacteroides fragilis/efeitos dos fármacos , Bacteroides fragilis/genética , Citocinas/metabolismo , Resistência Microbiana a Medicamentos/genética , Resistência Microbiana a Medicamentos/fisiologia , Ilhas Genômicas , Masculino , Camundongos , Anotação de Sequência Molecular , Projetos Piloto , Medição de Risco
18.
Toxicol Lett ; 319: 31-39, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31707105

RESUMO

The bioabsorption and biotoxicity of cadmium are closely related to its binding form. Currently, total concentration is used as the indicator for evaluating cadmium toxicity in food, but it might not accurately reflect cadmium's toxic effects. This study attempted to evaluate the toxicity of the different forms of cadmium including cadmium-malate, cadmium-glutathione, and cadmium-metallothionein that are commonly found in food. The in vitro physiologically based extraction test (PBET) combined with Visual MINTEQ modeling was used to predict the toxicity of different forms of cadmium, and acute toxicity testing was performed in mice for validating their results. The in vivo experimental results showed that different forms of cadmium had diverse biotoxicities of which PBET was a good predictor. In particular, the simulation of cadmium ions in PBET using the MINTEQ software revealed that the free cadmium ion content in the simulated intestinal fluid had a superior linear relationship than the total cadmium concentration with the toxicology indexes. Verification using the other two forms of cadmium confirmed the accuracy of the prediction of their biotoxicity. These findings hopefully provide an important reference for a more accurate and rapid safety assessment of cadmium in food.


Assuntos
Compostos de Cádmio/farmacocinética , Compostos de Cádmio/toxicidade , Análise de Alimentos , Animais , Disponibilidade Biológica , Cádmio/análise , Simulação por Computador , Fezes/química , Contaminação de Alimentos , Absorção Intestinal , Masculino , Camundongos , Camundongos Endogâmicos ICR , Valor Preditivo dos Testes , Software , Distribuição Tecidual
19.
J Agric Food Chem ; 68(1): 128-137, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31825613

RESUMO

Salmonellosis is a world-wide epidemic, and n-3 long chain polyunsaturated fatty acids (LCPUFAs) possess various health benefits. This study is aimed to investigate the preventive effects of n-3 LCPUFAs against Salmonella infection. By pretreatment with n-3 LCPUFAs, but not n-6 LCPUFAs, the survival rate of the infected mice was increased. Further studies showed that n-3 LCPUFAs significantly increased the fecal contents of short-chain fatty acids (SCFAs). The cytokine expression in the liver and production in serum were both modulated by n-3 LCPUFAs into an anti-inflammatory profile against infection. Moreover, the changes in gut microbiota by n-3 LCPUFAs favored the host against pathogens, closely related to the modified SCFA production and immune responses. In conclusion, n-3 LCPUFAs prevented Salmonella infection through multiple mechanisms, especially by the interaction with gut microbiota and host immunology. Our results suggested great perspectives for n-3 LCPUFAs and their related products to control the prevalence of Salmonella, a most predominant food-borne pathogen.


Assuntos
Suplementos Nutricionais/análise , Ácidos Graxos Ômega-3/administração & dosagem , Infecções por Salmonella/prevenção & controle , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Modelos Animais de Doenças , Ácidos Graxos Voláteis/metabolismo , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Salmonella/efeitos dos fármacos , Salmonella/fisiologia , Infecções por Salmonella/microbiologia
20.
J Dairy Sci ; 103(1): 87-97, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677844

RESUMO

Previous research reported that fermented yak milk had a diverse microbial composition. For this study, raw yak milk, qula, and fermented yak milk samples were collected from the Aba Tibetan autonomous region of China. The genus and species microbial composition of these samples were analyzed by high-throughput sequencing of 16S rRNA and groEL gene amplicons, and the volatile profile of the samples was quantified by gas chromatography-mass spectrometry. The results indicated variation in abundance of microbiota at the genus level among the fermented yak milk samples, with Lactobacillus as the most abundant genus in the majority of samples, ranging from 41.6 to 98.3%. The volatile profile of the samples varied among those collected from different villages. Correlations between bacterial composition and volatile compounds of the samples were also observed. Lactobacillus displayed a significant correlation with volatile compounds such as benzaldehyde, 2,3-pentanedione, ethanol, and ethyl acetate, whereas the samples with relatively high abundance of Streptococcus and Lactococcus displayed relatively low contents of volatile compounds.


Assuntos
Bovinos , Produtos Fermentados do Leite/microbiologia , Lactobacillus/isolamento & purificação , Lactococcus/isolamento & purificação , Streptococcus/isolamento & purificação , Animais , Reatores Biológicos , China , Fermentação , Lactobacillus/genética , RNA Ribossômico 16S/genética
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