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2.
J Exp Clin Cancer Res ; 42(1): 53, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859266

RESUMO

BACKGROUND: Although the role and mechanism of neutrophils in tumors have been widely studied, the precise effects of aryl hydrocarbon receptor nuclear translocator (ARNT) on neutrophils remain unclear. In this study, we investigated the roles of ARNT in the function of CD11b+Gr1+ neutrophils in colitis-associated colorectal cancer. METHODS: Wild-type (WT), ARNT myeloid-specific deficient mice and a colitis-associated colorectal cancer mouse model were used in this study. The level and functions of CD11b+Gr1+ cells were evaluated by flow cytometry and confocal microscopy. RESULTS: We found that ARNT deficiency drives neutrophils recruitment, neutrophil extracellular trap (NET) development, inflammatory cytokine secretion and suppressive activities when cells enter the periphery from bone marrow upon colorectal tumorigenesis. ARNT deficiency displays similar effects to aryl hydrocarbon receptor (AHR) deficiency in neutrophils. CXCR2 is required for NET development, cytokine production and recruitment of neutrophils but not the suppressive activities induced by Arnt-/- in colorectal cancer. The gut microbiota is essential for functional alterations in Arnt-/- neutrophils to promote colorectal cancer growth. The colorectal cancer effects of Arnt-/- neutrophils were significantly restored by mouse cohousing or antibiotic treatment. Intragastric administration of the feces of Arnt-/- mice phenocopied their colorectal cancer effects. CONCLUSION: Our results defined a new role for the transcription factor ARNT in regulating neutrophils recruitment and function and the gut microbiota with implications for the future combination of gut microbiota and immunotherapy approaches in colorectal cancer.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto , Neoplasias Associadas a Colite , Microbioma Gastrointestinal , Neutrófilos , Animais , Camundongos , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Citocinas
3.
Neural Regen Res ; 18(9): 1999-2004, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36926725

RESUMO

Animal experiments have shown that injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells can promote recovery from spinal cord injury. To investigate whether injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells can be used to treat spontaneous intracerebral hemorrhage, this non-randomized phase I clinical trial recruited patients who met the inclusion criteria and did not meet the exclusion criteria of spontaneous intracerebral hemorrhage treated in the Characteristic Medical Center of Chinese People's Armed Police Force from May 2016 to December 2020. Patients were divided into three groups according to the clinical situation and patient benefit: control (n = 18), human umbilical cord-derived mesenchymal stem cells (n = 4), and combination (n = 8). The control group did not receive any transplantation. The human umbilical cord-derived mesenchymal stem cells group received human umbilical cord-derived mesenchymal stem cell transplantation. The combination group received injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells. Patients who received injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells had more remarkable improvements in activities of daily living and cognitive function and smaller foci of intracerebral hemorrhage-related encephalomalacia. Severe adverse events associated with cell transplantation were not observed. Injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells appears to have great potential treating spontaneous intracerebral hemorrhage.

4.
Biomarkers ; 27(2): 188-195, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35001797

RESUMO

Background: Vitamin D deficiency has been associated with increased sepsis incidence and mortality in various populations. Vitamin D exerts its effect through vitamin receptor (VDR), and various single nucleotide polymorphisms have been reported to affects the expression and structure of the VDR. In the present study, we investigated the possible role of vitamin D deficiency and VDR polymorphisms in susceptibility to sepsis.Methods: 576 sepsis patients and 421 healthy controls were enrolled in the present study. Plasma vitamin D levels in patients and healthy controls were quantified by ELISA. Genetic variants in the VDR (FokI, TaqI, BsmI, and ApaI) were genotyped by TaqMan assay.Results: Reduced serum Vitamin D level was observed in subjects with sepsis compared to healthy controls (p ≤ 0.0001). Further, subjects with septic shock had diminished 25(OH) vitamin D compared to severe sepsis cases (p ≤ 0.0001). FokI variants and minor alleles were more prevalent in sepsis patients compared to healthy controls (Ff: p ≤ 0.0001, χ2 =17.39; ff: p=0.001, χ2 =10.79; f: p ≤ 0.0001, χ2 =23.51). Furthermore, combined plasma levels of 25(OH) vitamin D and FokI polymorphism revealed a significant role in a predisposition to sepsis and septic shock. However, the prevalence of other VDR polymorphisms (TaqI, BsmI and ApaI) were comparable among different clinical categories.Conclusions: Low 25(OH) vitamin D levels and FokI mutants are associated with an increased risk of sepsis and septic shock in a Chinese cohort.Clinical significanceLower levels of 25-OH vitamin D are highly prevalent in Sepsis patients.Subjects harbouring VDR FokI variants are predisposed to susceptibility to sepsis in the studied cohort.


Assuntos
Receptores de Calcitriol , Sepse , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Hospitais , Humanos , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Sepse/genética , Vitamina D
5.
Nutr Metab (Lond) ; 18(1): 26, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691721

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease and is characterized by excessive fat accumulation. Kaili Sour Soup, a food typical of Guizhou Province, is believed to have significant health benefits. Thus, we aimed to identify and assess the impact of Kaili Sour Soup on NAFLD and its underlying mechanism using integrative proteomic and lipidomic analysis. METHODS: A high-fat diet and male Wistar rats were used to construct a NAFLD rat model. Haematoxylin and eosin (HE) and Oil Red O staining analyses were used to perform the histologic examination. Proteomic analysis was utilized to systematically identify the global protein profile in NAFLD with and without Kaili Sour Soup treatment. Western blot assays were used to verify the expression of proteins screened by proteomic analysis. Lipidomic analysis was performed to screen lipid metabolism in NAFLD with and without Kaili Sour Soup treatment. RESULTS: Kaili Sour Soup alleviated high-fat diet (HFD)-induced fatty liver and had a normalizing effect on physiological and biochemical indicators of NAFLD, including body weight, liver weight, liver index, total cholesterol (TC), triglyceride (TG), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and insulin resistance level of homeostasis model assessment (HOMA-IR). Kaili Sour Soup decreased the levels of 13 proteins (Tmem44, Rnaseh2b, Gstm6l, LOC100910877, Rufy4, Slc12a2, Pcif1, P4503A1, Sult1e1, Nop53, AABR07065656.4, AABR07065789.3) that were upregulated by HFD and increased the levels of 3 proteins (Sult1c2, Sult1c2a, Snrnp48) that were downregulated by HFD. Kaili Sour Soup attenuated the HFD-induced increase in acyl carnitine (AcCa) and enhanced the HFD-induced decreases in gangliosides (GM3) and lysophosphatidylserine (LPS) in the NAFLD rat model. CONCLUSIONS: Altogether, this study revealed that Kaili Sour Soup attenuated HFD-induced fatty liver and systematically identified abnormal proteins and lipids involved in the role of Kaili Sour Soup in a NAFLD rat model.

6.
Scott Med J ; 66(1): 16-22, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32990500

RESUMO

BACKGROUND AND AIMS: The neurological damage caused by cardiac arrest (CA) can seriously affect quality of life. We investigated the effect of metformin pretreatment on brain injury and survival in a rat CA/cardiopulmonary resuscitation (CPR) model. METHODS AND RESULTS: After 14 days of pretreatment with metformin, rats underwent 9 minutes of asphyxia CA/CPR. Survival was evaluated 7 days after restoration of spontaneous circulation; neurological deficit scale (NDS) score was evaluated at days 1, 3, and 7. Proteins related to the endoplasmic reticulum (ER) stress response and autophagy were measured using immunoblotting. Seven-day survival was significantly improved and NDS score was significantly improved in rats pretreated with metformin. Metformin enhanced AMPK-induced autophagy activation. AMPK and autophagy inhibitors removed the metformin neuroprotective effect. Although metformin inhibited the ER stress response, its inhibitory effect was weaker than 4-PBA. CONCLUSION: In a CA/CPR rat model, 14-day pretreatment with metformin has a neuroprotective effect. This effect is closely related to the activation of AMPK-induced autophagy and inhibition of the ER stress response. Long-term use of metformin can reduce brain damage following CA/CPR.


Assuntos
Lesões Encefálicas/prevenção & controle , Reanimação Cardiopulmonar/efeitos adversos , Metformina/farmacologia , Fármacos Neuroprotetores/farmacologia , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Animais , Autofagia/efeitos dos fármacos , Lesões Encefálicas/etiologia , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ratos
7.
Oxid Med Cell Longev ; 2020: 6837982, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32318240

RESUMO

As a pair of differential isomers, Kaji-ichigoside F1 and Rosamultin are both pentacyclic triterpenoids isolated from the subterranean root of Potentilla anserina L., a plant used in folk medicine in western China as antihypoxia and anti-inflammatory treatments. We demonstrated that Kaji-ichigoside F1 and Rosamultin effectively prevented hypoxia-induced apoptosis in vascular endothelial cells. We established a hypoxia model, using EA.hy926 cells, to further explore the mechanisms. Hypoxia promoted the phosphorylation of AKT, ERK1/2, and NF-κB. In hypoxic cells treated with Kaji-ichigoside F1, p-ERK1/2 and p-NF-κB levels were increased, while the level of p-AKT was decreased. Treatment with Rosamultin promoted phosphorylation of ERK1/2, NF-κB, and AKT in hypoxic cells. Following the addition of LY294002, the levels of p-AKT, p-ERK1/2, and p-NF-κB decreased significantly. Addition of PD98059 resulted in reduced levels of p-ERK1/2 and p-NF-κB, while p-AKT levels were increased. Pharmacodynamic analysis demonstrated that both LY294002 and PD98059 significantly inhibited the positive effects of Kaji-ichigoside F1 on cell viability during hypoxia, consistent with the results of hematoxylin-eosin (H&E) staining, DAPI staining, and flow cytometry. The antihypoxia effects of Rosamultin were remarkably inhibited by LY294002 but promoted by PD98059. In Kaji-ichigoside F1- and Rosamultin-treated cells, Bcl2 expression was significantly upregulated, while expression of Bax and cytochrome C and levels of cleaved caspase-9 and cleaved caspase-3 were reduced. Corresponding to pharmacodynamic analysis, LY294002 inhibited the regulatory effects of Kaji-ichigoside F1 and Rosamultin on the above molecules, while PD98059 inhibited the regulatory effects of Kaji-ichigoside F1 but enhanced the regulatory effects of Rosamultin. In conclusion, Kaji-ichigoside F1 protected vascular endothelial cells against hypoxia-induced apoptosis by activating the ERK1/2 signaling pathway, which positively regulated the NF-κB signaling pathway and negatively regulated the PI3K/AKT signaling pathway. Rosamultin protected vascular endothelial cells against hypoxia-induced apoptosis by activating the PI3K/AKT signaling pathway and positively regulating ERK1/2 and NF-κB signaling pathways.


Assuntos
Células Endoteliais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Triterpenos/farmacologia , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Células Endoteliais/enzimologia , Células Endoteliais/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
8.
Life Sci ; 252: 117666, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298737

RESUMO

AIMS: Euscaphic acid and Tormentic acid are aglycones of Kaji-ichigoside F1 and Rosamultin, respectively. These four compounds are pentacyclic triterpenoid, isolated from the subterranean root of the Potentilla anserina L. Based on the protective roles against hypoxia-induced apoptosis of Euscaphic acid and Tormentic acid in vascular endothelial cells, this study was designed to determine the mechanisms. MAIN METHODS: The model of hypoxic injuries in EA. hy926 cells was established. Through applications of PI3K/AKT inhibitor, LY294002 and ERK1/2 inhibitor, PD98059, we explored the relationships between pharmacodynamic mechanisms and PI3K/AKT or ERK 1/2 signaling pathway. The anti-hypoxic effects were studied by methyl-thiazolyl-tetrazolium (MTT) assay, Hematoxylin-Eosin (HE) staining, DAPI staining, and flow cytometry. The mechanisms of anti-mitochondrial apoptosis were explored by western blot. The expressions of p-ERK 1/2, ERK 1/2, p-AKT, AKT, p-NF-κB, NF-κB, Bcl-2, Bax, Cyt C, cleaved caspase-9 and cleaved caspase-3 were detected. KEY FINDINGS: Euscaphic acid protected vascular endothelial cells against hypoxia-induced apoptosis via ERK1/2 signaling pathway, and Tormentic acid brought its efficacy into full play via PI3K/AKT and ERK1/2 signaling pathways. In addition, PI3K/AKT signaling pathway positively regulated ERK1/2 pathway, and ERK1/2 pathway negatively regulated PI3K/AKT pathway. SIGNIFICANCE: This evidence provides theoretical and experimental basis for the following research on anti-hypoxic drugs of Potentilla anserina L.


Assuntos
Apoptose/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Triterpenos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Cromonas/farmacologia , Células Endoteliais/metabolismo , Flavonoides/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Potentilla/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
9.
Front Microbiol ; 10: 2891, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921067

RESUMO

Most bacteria in the human gut are difficult to culture, and culturomics has been designed to overcome this issue. Culturomics makes it possible to obtain living bacteria for further experiments, unlike metagenomics. However, culturomics is work-intensive, which prevents its wide application. In this study, we performed a 30-day continuous enrichment in blood culture bottles and cultured bacterial isolates from pre-cultures removed at different time points. We compared the bacteria isolated from the enriched culture with or without adding fresh medium after each pre-culture was removed. We also compared "experienced" colony picking (i.e., picking two to three colonies for each recognized colony type) and picking all the colonies from each plate. In total, from five fecal samples, 106 species were isolated, including three novel species and six that have not previously been isolated from the human body. Adding fresh medium to the culture increased the rate of bacterial species isolation by 22% compared with the non-supplemented culture. Picking all colonies increased the rate of bacterial isolation by only 8.5% compared with experienced colony picking. After optimization through statistical analysis and simulation, sampling aerobic and anaerobic enrichment cultures at six and seven time-points, respectively, is likely to isolate >90% of bacterial species, reducing the workload by 40%. In conclusion, an extended enrichment step ensures isolation of different bacterial species at different time-points, while adding the same quantity of fresh medium after sampling, the experienced picking and the optimized time-points favor the chance of isolating more bacterial species with less work.

10.
BMC Microbiol ; 19(1): 308, 2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-31888576

RESUMO

BACKGROUND: Culturomics can ascertain traces of microorganisms to be cultivated using different strategies and identified by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry or 16S rDNA sequencing. However, to cater to all requirements of microorganisms and isolate as many species as possible, multiple culture conditions must be used, imposing a heavy workload. In addition, the fast-growing bacteria (e.g., Escherichia) surpass the slow-growing bacteria in culture by occupying space and using up nutrients. Besides, some bacteria (e.g., Pseudomonas) suppress others by secreting antibacterial metabolites, making it difficult to isolate bacteria with lower competence. Applying inhibitors to restrain fast-growing bacteria is one method to cultivate more bacterial species from human feces. RESULTS: We applied CHIR-090, an LpxC enzyme inhibitor that has antibacterial activity against most Gram-negative bacteria, to culturomics of human fresh feces. The antibacterial activity of CHIR-090 was first assessed on five Gram-negative species of bacteria (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus vulgaris, and Bacteroides vulgatus), all of which are commonly isolated from the human gut. Then, we assessed suitable concentrations of the inhibitor. Finally, CHIR-090 was applied in blood culture bottles for bacterial cultivation. In total, 102 species from five samples were identified. Of these, we found one new species, two species not reported previously in the human gut, and 11 species not previously isolated from humans. CONCLUSIONS: CHIR-090 can suppress E. coli, P. aeruginosa, K. pneumoniae, Pro. vulgaris, but not B. vulgatus. Compared with the non-inhibitor group, CHIR-090 increased bacteria isolation by 23.50%, including four species not reported in humans and one new species. Application of LpxC enzyme inhibitor in culturomics increased the number of species isolated from the human gut.


Assuntos
Amidoidrolases/antagonistas & inibidores , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Técnicas Bacteriológicas/métodos , Inibidores Enzimáticos/farmacologia , Microbioma Gastrointestinal , Adulto , Bactérias/isolamento & purificação , Hemocultura/métodos , DNA Bacteriano/genética , Fezes/microbiologia , Voluntários Saudáveis , Humanos , Ácidos Hidroxâmicos/farmacologia , Análise de Sequência de DNA , Treonina/análogos & derivados , Treonina/farmacologia
11.
PeerJ ; 6: e5637, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30280023

RESUMO

Microbiota-driven variations in the inflammatory response are predicted to regulate host responses to infection. Increasing evidence indicates that the gastrointestinal and respiratory tracts have an intimate relationship with each other. Gut microbiota can influence lung immunity whereby gut-derived injurious factors can reach the lungs and systemic circulation via the intestinal lymphatics. The intestinal microbiota's ability to resist colonization can be extended to systemic infections or to pathogens infecting distant sites such as the lungs. Unlike the situation with large mammals, the microtus Yersinia pestis 201 strain exhibits strong virulence in mice, but nearly no virulence to large mammals (such as guinea pigs). Hence, to assess whether the intestinal microbiota from guinea pigs was able to affect the sensitivity of mice to challenge infection with the Y. pestis 201 strain, we fed mice with guinea pig diets for two months, after which they were administered 0.5 ml of guinea pig fecal suspension for 30 days by oral gavage. The stools from each mouse were collected on days 0, 15, and 30, DNA was extracted from them, and 16S rRNA sequencing was performed to assess the diversity and composition of the gut microbiota. We found that the intestinal microbiota transplants from the guinea pigs were able to colonize the mouse intestines. The mice were then infected with Yersinia pestis 201 by lung invasion, but no statistical difference was found in the survival rates of the mice that were colonized with the guinea pig's gut microbiota and the control mice. This indicates that the intestinal microbiota transplantation from the guinea pigs did not affect the sensitivity of the mice to pneumonic plague.

12.
Front Immunol ; 9: 1040, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29868005

RESUMO

Antibiotic-associated diarrhea (AAD) is iatrogenic diarrhea characterized by disruption of the gut microbiota. Probiotics are routinely used to treat AAD in clinical practice; however, the effectiveness and mechanisms by which probiotics alleviate symptoms remain poorly understood. We previously isolated a non-toxic Bacteroides fragilis strain ZY-312, which has been verified to be beneficial in certain infection disorders. However, the precise role of this commensal bacterium in AAD is unknown. In this study, we successfully established an AAD rat model by exposing rats to appropriate antibiotics. These rats developed diarrhea symptoms and showed alterations in their intestinal microbiota, including overgrowth of some pathogenic bacteria. In addition, gastrointestinal barrier defects, indicated by compromised aquaporin expression, aberrant tight junction proteins, and decreased abundance of mucus-filled goblet cells, were also detected in ADD rats compared with control animals. Of note, oral treatment with B. fragilis strain ZY-312 ameliorated AAD-related diarrhea symptoms by increasing the abundance of specific commensal microbiota. Interestingly, we demonstrated that these changes were coincident with the restoration of intestinal barrier function and enterocyte regeneration in AAD rats. In summary, we identified a potential probiotic therapeutic strategy for AAD and identified the vital roles of B. fragilis strain ZY-312 in modulating the colonic bacterial community and participating in microbiota-mediated epithelial cell proliferation and differentiation.


Assuntos
Antibacterianos/efeitos adversos , Infecções Bacterianas/terapia , Bacteroides fragilis , Diarreia/terapia , Microbioma Gastrointestinal/efeitos dos fármacos , Probióticos/uso terapêutico , Animais , Antibacterianos/administração & dosagem , Diarreia/microbiologia , Modelos Animais de Doenças , Trato Gastrointestinal/efeitos dos fármacos , Intestinos/imunologia , Intestinos/microbiologia , Masculino , Probióticos/administração & dosagem , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/uso terapêutico , Ratos , Ratos Sprague-Dawley , Simbiose
13.
Artigo em Inglês | MEDLINE | ID: mdl-28553617

RESUMO

Bacteroides fragilis is an anaerobic, Gram-negative, commensal bacterium of the human gut. It plays an important role in promoting the maturation of the immune system, as well as suppressing abnormal inflammation. Many recent studies have focused on the relationship between B. fragilis and human immunity, and indicate that B. fragilis has many useful probiotic effects. As inhibition of intestinal pathogens is an important characteristic of probiotic strains, this study examined whether B. fragilis could inhibit pathogenic bacteria. Results showed that Vibrio parahaemolyticus was inhibited by B. fragilis in vitro, and that B. fragilis could protect both RAW 264.7 and LoVo cells from damage caused by V. parahaemolyticus. Using in vivo imaging, we constructed a light-emitting V. parahaemolyticus strain and showed that B. fragilis might shorten the colonization time and reduce the number of lux-expressing bacteria in a mouse model. These results provide useful information for developing B. fragilis into a probiotic product, and also indicate that this commensal bacterium might aid in the clinical treatment of gastroenteritis caused by V. parahaemolyticus.


Assuntos
Antibiose , Bacteroides fragilis/fisiologia , Diagnóstico por Imagem/métodos , Medições Luminescentes/métodos , Vibrioses/diagnóstico por imagem , Vibrioses/terapia , Vibrio parahaemolyticus/fisiologia , Animais , Bacteroides fragilis/crescimento & desenvolvimento , Linhagem Celular , Modelos Animais de Doenças , Doenças Transmitidas por Alimentos/terapia , Gastroenterite/terapia , Humanos , Intestinos/microbiologia , Camundongos , Probióticos , Células RAW 264.7 , Vibrio parahaemolyticus/crescimento & desenvolvimento , Vibrio parahaemolyticus/patogenicidade
14.
Front Microbiol ; 8: 435, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367145

RESUMO

Commensal non-toxigenic Bacteroides fragilis confers powerful health benefits to the host, and has recently been identified as a promising probiotic candidate. We previously isolated B. fragilis strain ZY-312 and identified it as a novel strain based on 16S rRNA sequencing and morphological analyses. We also determined that ZY-312 displayed desirable probiotic properties, including tolerance to simulated digestive fluid, adherence, and in vitro safety. In this study, we aim to investigate whether ZY-312 meets the safety criteria required for probiotic bacteria through comprehensive and systematic evaluation. Consequently, the fatty acid profile, metabolite production, and biochemical activity of strain ZY-312 were found to closely resemble descriptions of B. fragilis in Bergey's manual. Taxonomic identification of strain ZY-312 based on whole genome sequencing indicated that ZY-312 and ATCC 25285 showed 99.99% similarity. The 33 putative virulence-associated factors identified in ZY-312 mainly encoded structural proteins and proteins with physiological activity, while the lack of bft indicated that ZY-312 was non-toxigenic. In vivo safety was proven in both normal and immune-deficient mice. The 11 identified antibiotic resistance genes were located on the chromosome rather than on a plasmid, ruling out the risk of plasmid-mediated transfer of antibiotic resistance. In vitro, ZY-312 showed resistance to cefepime, kanamycin, and streptomycin. Finally, and notably, ZY-312 exhibited high genetic stability after 100 passages in vitro. This study supplements the foundation work on the safety evaluation of ZY-312, and contributes to the development of the first probiotic representative from the dominant Bacteroidetes phylum.

15.
Biomed Tech (Berl) ; 62(5): 467-479, 2017 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-28076291

RESUMO

The construction of engineered bone mostly focuses on simulating the extracellular matrix (ECM) for proper biological activity. However, the complexity of architecture and the variability of the mechanical properties of natural bones are related to individual differences in age, nutritional state, mechanical loading and disease status. Defect substitutions should be normed with the host natural bone, balancing architectural and mechanical adaption, as well as biological activity. Using a freeform fabrication (FFF) method, we prepared polycaprolactone (PCL) scaffolds with different architectures. With simulation of structural and mechanical parameters of rabbit femur cancellous bone, individual defect substitution with the characteristics of the rabbit femur was obtained with high porosity and connectivity. Biological adaption in vitro was examined and osteoid formation in vivo was assessed by implantation in situ. Simulating the femur cancellous bone, 300-µm FFF PCL scaffolds had better architectural and mechanical properties. The protocol produced an architecturally, mechanically and biologically adaptive construction of an individual model for rapid-prototype PCL scaffolds. A guide system was developed to accurately reproduce virtually individual defect substitutions of the bone.


Assuntos
Osso e Ossos/química , Fêmur/fisiologia , Osteogênese/fisiologia , Poliésteres/química , Animais , Osso e Ossos/fisiologia , Fêmur/química , Porosidade , Coelhos
16.
Sci Bull (Beijing) ; 62(15): 1052-1063, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36659332

RESUMO

The gut microbiota plays a key role in obesity and related metabolic disorders, and multiple factors including diet, host genotype, and age regulate it. Many studies have examined the contribution of extrinsic factors to the regulation of the gut microbiota, but the importance of the host genetic constitution cannot be ignored. Interleukin 17A (IL-17A), a pro-inflammatory cytokine, is important in the defense against infection and diseases. Here, we investigated the association among IL-17, a high-fat diet (HFD), and the gut microbiota. Mice deficient in IL-17A were resistant to diet-induced obesity and related diseases. Compared with the Il-17a-/- mice, wild-type (WT) mice challenged with HFD showed obvious weight fluctuations, such as those seen in type 2 diabetes, and hematological changes similar to those associated with metabolic syndrome. However, housing WT mice and Il-17a-/- mice together significantly alleviated these symptoms in the WT mice. A metagenomic analysis of the mouse feces indicated that the microbial community compositions of these two groups differed before HFD feeding. The HFD mediated shifts in the gut microbial compositions, which were associated with the mouse phenotypes. We also identified potentially beneficial and harmful species present during this period, and drew networks of the most abundant species. A functional analysis indicated pathway changes in the WT and Il-17a-/- mice when fed the HFD. Collectively, these data underscore the importance of the host factor IL-17A in shaping and regulating the gut microbiota, which conversely, influences the host health.

17.
Sci Rep ; 6: 29401, 2016 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-27381366

RESUMO

Commensal Bacteroides fragilis possesses immune-regulatory characteristics. Consequently, it has been proposed as a potential novel probiotic because of its therapeutic effects on immune imbalance, mental disorders and inflammatory diseases. Macrophages play a central role in the immune response, developing either a classical-M1 or an alternative-M2 phenotype after stimulation with various signals. The interactions between macrophages and B. fragilis, however, remain to be defined. Here, a new isolate of B. fragilis, ZY-312, was shown to possess admirable properties, including tolerance to simulated gastric fluid, intestinal fluid and ox bile, and good safety (MOI = 100, 200) and adherent ability (MOI = 100) to LoVo cells. Isolate ZY-312 cell lysate promoted phagocytosis of fluorescent microspheres and pathogenic bacteria in bone marrow-derived macrophage (BMDM) cells. Gene expression of IL-12, iNOS and IL-1ß in BMDM cells was increased after treatment with ZY-312, indicating the induction of M1 macrophages, consistent with enhanced secretion of NO. Cell surface expression of CD80 and CD86 was also increased. This study is the first to demonstrate that B. fragilis enhances the phagocytic functions of macrophages, polarising them to an M1 phenotype. Our findings provide insight into the close relationship between B. fragilis and the innate immune system.


Assuntos
Bacteroides fragilis/isolamento & purificação , Bacteroides fragilis/fisiologia , Macrófagos/citologia , Fagocitose , Animais , Aderência Bacteriana , Linhagem Celular , Polaridade Celular , Humanos , Imunidade Inata , Interleucina-12/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/metabolismo
18.
ISA Trans ; 60: 12-20, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26593968

RESUMO

This paper revisits the problems of robust stability analysis and control of continuous-time systems with state-dependent uncertainties. First, a more general polytopic model describing systems with state-dependent uncertain parameters is proposed, and such a system model is more applicable in practice. A low conservative stability condition is obtained for the system by introducing the Lagrange multiplier term and adding some weight matrix variables. Then, based on our proposed idea, the output-feedback controllers will be designed in two cases: (1) the system matrices share the same polytopic parameters; (2) the system matrices do not share the same polytopic parameters. The controllers are designed in a model-dependent manner, which can provide more flexibilities in control synthesis. Besides, a decay rate can be set in advance to achieve better system performances. Finally, a numerical example together with a classic mechanical system is used to demonstrate the effectiveness and applicability of our theoretical findings.

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