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Expression and purification of ß-galactosidases derived from Bifidobacterium provide a new resource for efficient lactose hydrolysis and lactose intolerance alleviation. Here, we cloned and expressed two ß-galactosidases derived from Bifidobacterium. The optimal pH for BLGLB1 was 5.5, and the optimal temperature was 45 °C, at which the enzyme activity of BLGLB1 was higher than that of commercial enzyme E (300 ± 3.6 U/mg) under its optimal conditions, reaching 2200 ± 15 U/mg. The optimal pH and temperature for BPGLB1 were 6.0 and 45 °C, respectively, and the enzyme activity (0.58 ± 0.03 U/mg) under optimum conditions was significantly lower than that of BLGLB1. The structures of the two ß-galactosidase were similar, with all known key sites conserved. When o-nitrophenyl-ß-D-galactoside (oNPG) was used as an enzyme reaction substrate, the maximum reaction velocity (Vmax) for BLGLB1 and BPGLB1 was 3700 ± 100 U/mg and 1.1 ± 0.1 U/mg, respectively. The kinetic constant (Km) of BLGLB1 and BPGLB1 was 1.9 ± 0.1 and 1.3 ± 0.3 mmol/L, respectively. The respective catalytic constant (kcat) of BLGLB1 and BPGLB1 was 1700 ± 40 s-1 and 0.5 ± 0.02 s-1, respectively; the respective kcat/Km value of BLGLB1 and BPGLB1 was 870 L/(mmolâs) and 0.36 L/(mmolâs), respectively. The Km, kcat and Vmax values of BLGLB1 were superior to those of earlier reported ß-galactosidase derived from Bifidobacterium. Overall, BLGLB1 has potential application in the food industry.
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Bifidobacterium longum , Bifidobacterium pseudocatenulatum , Bifidobacterium/genética , Bifidobacterium/metabolismo , Bifidobacterium longum/genética , Bifidobacterium pseudocatenulatum/metabolismo , Clonación Molecular , Concentración de Iones de Hidrógeno , Cinética , Lactosa/metabolismo , Temperatura , beta-Galactosidasa/químicaRESUMEN
The Luneburg lens is widely applied in both the optical and microwave regimes because it offers high gain and a wide beam-scanning range. However, Luneburg lens typically suffer from low efficiency which is caused by the dielectric loss of medium employed. To address this issue, we propose herein a general method for discretization of two-dimensional Luneburg lens based on correctional effective-medium theory. In discrete Luneburg, the efficiency is not dependent on the employed medium roughly because that the main component in the lens is air, resulting into a significant improvement of efficiency. Subsequently, a systemic study of lens discretization is presented, which is validated by a discrete Luneburg lens easily fabricated by using 3D printing. In addition, a novel wave-patch reduction feature allows the discrete lens to function as well. This work presents a fundamental theory for lens discretization, which is valid not only for the Luneburg lens but also for other types of lenses. It can be applied in imaging, antennas, or phase manipulation in both the optical and microwave bands.
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The extracellular secreted protein of Bifidobacterium longum (B. longum) plays an important role in maintaining the homeostasis of the human intestinal microenvironment. However, the mechanism(s) of interaction remain unclear. Lysozyme is a kind of antibacterial peptide. In this study, the amino acid sequence of a lysozyme-like protein of B. longum based on whole-genome data of an isolate from human gut feces was found. We further predicted functional domains from the amino acid sequence, purified the protein, and verified its bioactivity. The growth of some bacteria were significantly delayed by the 020402_LYZ M1 protein. In addition, the gut microbiota was analyzed via high-throughput sequencing of 16S rRNA genes and an in vitro fermentation model, and the fluctuations in the gut microbiota under the treatment of 020402_LYZ M1 protein were characterized. The 020402_LYZ M1 protein affected the composition of human gut microbiota significantly, implying that the protein is able to communicate with intestinal microbes as a regulatory factor.
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Proteínas Bacterianas/metabolismo , Bifidobacterium/metabolismo , Microbioma Gastrointestinal , Interacciones Microbianas , Proteínas Bacterianas/química , Bifidobacterium/enzimología , Biología Computacional/métodos , Heces/microbiología , Humanos , Modelos Moleculares , Proteoma , Proteómica/métodos , Relación Estructura-ActividadRESUMEN
Herein, we propose an approach for sensitivity improvement of dual-axis strain sensing using the property of a metasurface (MS) that the phase response shifts sharply with the MS deformation. A feasible approach for phase measurement is first demonstrated by calculating multi-polarized reception when the incident electromagnetic (EM) wave has anisotropic phase values. A flexible MS consisting of periodically arranged lantern-shaped elements is designed and fabricated for dual-axis strain sensing and evaluation based on the proposed method. The simulation and measurement results demonstrated a high sensitivity of the proposed MS for strain sensing in the microwave band. The method can be used potentially in both pressure and tensile sensing. Moreover, the operational frequency can be extended to the THz range and even to the optical band.
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OBJECTIVE: Raising awareness of acquired hemophilia A (AHA) and early diagnosis is critical to reduce the associated mortality rate. We aimed to characterize acquired hemophilia in Chinese patients and evaluate the effectiveness of immunotherapy. METHODS: The clinical characteristics, laboratory test data, therapeutic approaches, and outcomes of 20 patients with AHA who were admitted to Xi'an Central Hospital between January 2012 and December 2020 were retrospectively studied. RESULTS: Nine of the patients (45%) were treated by single glucocorticoid administration; three (15%) with cyclophosphamide (CP) in combination with a glucocorticoid; four individuals (20%) received a combination therapy of rituximab with CP and glucocorticoid or rituximab with CP, vincristine, and a glucocorticoid; three (15%) by injection of human immunoglobulin in combination with a glucocorticoid; and one (5%) with CP alone. Six patients (30%) achieved total remission and 11 (55%) partial remission (PR), but three (15%) did not enter remission, indicating an objective response rate of 85%. CONCLUSION: Combination therapy with rituximab or intravenous human immunoglobulin achieves superior results in some patients with AHA. Immunosuppression and the administration of coagulation factors can rapidly control the disease and are efficacious, but >50% of patients only achieved PR. These findings suggest that the complete elimination of inhibitors requires prolonged immunosuppression therapy.
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Ciclofosfamida , Hemofilia A , Inmunoterapia , Rituximab , Humanos , Hemofilia A/inmunología , Hemofilia A/tratamiento farmacológico , Hemofilia A/terapia , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Femenino , Anciano , Adulto , Rituximab/uso terapéutico , Rituximab/administración & dosificación , Ciclofosfamida/uso terapéutico , Ciclofosfamida/administración & dosificación , Inmunoterapia/métodos , Resultado del Tratamiento , Glucocorticoides/uso terapéutico , Glucocorticoides/administración & dosificación , Inmunoglobulinas Intravenosas/uso terapéutico , Inmunoglobulinas Intravenosas/administración & dosificación , Vincristina/uso terapéutico , Vincristina/administración & dosificación , Quimioterapia Combinada , Inmunosupresores/uso terapéuticoRESUMEN
Microbe-driven ammonia nitrogen removal plays a crucial role in the nitrogen cycle and wastewater treatment. However, the rational methods and mechanisms for boosting nitrogen conversion through microbial domestication are still limited. Herein, a combined alkali-photocatalytic stimulation strategy was developed to activate the Halomonas shizuishanensis DWK9 for efficient ammonia nitrogen removal. The strain DWK9 selected from saline-alkaline soil in Northwestern China possessed strong resistance to stress of saline-alkaline environment and free radicals, and was abundant in nitrogen conversion genes, thus is an ideal model for advanced microbial domestication. Bacterial in the combined alkali-photocatalytic stimulation group achieved a high ammonia nitrogen conversion rate of 67.5 %, 10 times outperforming the non-stimulated and single alkali/photocatalytic stimulation control groups. Morphology analysis revealed that the bacteria in the alkali-photocatalytic stimulated group formed a favorable structure for bioelectric transfer. Remarkably, the domesticated bacteria demonstrated improved electrochemical properties, including increased current capacity and lower overpotentials and impedance. Prokaryotic transcription genetic analysis together with qPCR analysis showed upregulation of denitrification-related metabolic pathway genes. A novel FAD dependent and NAD(P)H independent energy mode has been proposed. The universality and effectiveness of the as-developed combined alkali-photocatalytic microbial domestication strategy were further validated through indicator fish survival experiments. This work provides unprecedented degrees of freedom for the exploration of rational microbial engineering for optimized and controllable biogeochemical conversion.
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Chitosan (CS) has been extensively used as a protein drug and gene delivery carrier, but its delivery efficiency is unsatisfactory. In this study, a mannose ligand was used to modify CS, which could enhance the delivery efficiency of CS via mannose receptor-mediated endocytosis. A preventative anti-GRP DNA vaccine (pCR3.1-VS-HSP65-TP-GRP6-M2, pGRP) was condensed with mannosylated chitosan (MCS) to form MCS/pGRP nanoparticles. Nanoparticles were intranasally administered in a subcutaneous mice prostate carcinoma model to evaluate the efficacy on inhibition of the growth of tumor cells. The titers of anti-GRP IgG that lasted for 11 weeks were significantly higher than that for administration of CS/pGRP nanoparticles (p < 0.01) and intramuscular administration of a pGRP solution (p < 0.05) to mice. In addition, immunization with MCS/pGRP nanoparticles could suppress the growth of tumor cells. The average tumor weight (0.79 ± 0.30 g) was significantly lower than that in the CS/pGRP nanoparticle group (1.69 ± 0.15 g) (p < 0.01) or that in the pGRP group (1.12 ± 0.37 g) (p < 0.05). Cell binding and cellular uptake results indicated that MCS/pGRP nanoparticles bound with C-type lectin receptors on macrophages. MCS was an efficient targeting gene delivery carrier and could be used in antitumor immunotherapy.
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Quitosano/química , Manosa/química , Nanopartículas/química , Vacunas/administración & dosificación , Administración Intranasal , Animales , Western Blotting , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Inmunoterapia , Masculino , Ratones , Ratones Endogámicos C57BL , Nanopartículas/administración & dosificación , Mucosa Nasal/metabolismo , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/terapia , Vacunas/química , Vacunas/uso terapéuticoRESUMEN
This study aimed to investigate the metabolic and population responses of gut microbiota to resistant starch (RS3) in the presence of exogenous Lactiplantibacillus plantarum strain 84-3 (Lp84-3) in vitro and in vivo. Lp84-3 promoted acetate, propionate, and butyrate production from RS3 by gut microbiota and increased Lactobacillus and Blautia contents in vitro. Furthermore, in the presence of Lp84-3, starch granules presented a "dot-by-hole" fermentation pattern. Administration of Lp84-3 with RS3 increased the level of SCFA-producing Faecalibaculum, Parabacteroides, Alistipes, and Anaeroplasma in the faeces of rates, with Lactobacillus and Akkermansia representing the key genera that significantly promoted SCFAs, especially propionate and butyrate. Lp84-3 with RS3 promoted genes related to tryptophan synthase (EC 4.2.1.20) and beta-glucosidase (EC 3.2.1.21) in faecal bacteria. Our findings highlight the ability of Lp84-3 to enhance RS3 degradation, possibly by promoting SCFA-producing bacteria, and indicate that Lp84-3 could be a potential probiotic with a beneficial effect on gut microbiota.
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Microbioma Gastrointestinal , Humanos , Ratas , Animales , Fermentación , Almidón Resistente/metabolismo , Ácidos Grasos Volátiles/metabolismo , Propionatos/metabolismo , Butiratos/metabolismo , Bacterias/metabolismo , Heces/microbiología , Lactobacillus/metabolismo , BacteroidetesRESUMEN
The ß-subunit of human chorionic gonadotropin (ß-hCG) is ectopically expressed in various types of cancer and has been utilized as an antigenic target in anti-cancer vaccines. In view of the low immunogenicity of this self-peptide, we designed a method based on the isocaudamer technique to generate 14 tandem repeats of the 10-residue sequence X of ß-hCG (109-118). These tandemly repeated copies were then combined with ß-hCG C-terminal 37 peptides (CTP37) and finally fused to mycobacterial heat-shock protein 65 (HSP65) to construct a fusion protein HSP65-X14-ßhCGCTP37 as an immunogen. In this study, BALB/c female mice were immunized via subcutaneous injection of the designed protein. Humoral immune and cellular immune responses were effectively elicited. A high titer of anti-ß-hCG antibody was detected in immunized mice sera by enzyme-linked immunosorbent assay and verified by Western blot analysis. The fusion protein, HSP65-X14-ß-hCGCTP37, effectively inhibited the growth of Ehrlich ascites carcinoma in mice. These results suggest that HSP65-X14-ßhCGCTP37 may be an effective tumor vaccine, and the use of multiple tandem repeats of a certain epitope is an effective method to overcome the low immunogenicity of self-peptide antigens.
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Proteínas Bacterianas/genética , Vacunas contra el Cáncer/inmunología , Chaperonina 60/genética , Gonadotropina Coriónica Humana de Subunidad beta/inmunología , Péptidos/inmunología , Proteínas Recombinantes de Fusión/inmunología , Animales , Anticuerpos/sangre , Anticuerpos/inmunología , Secuencia de Bases , Vacunas contra el Cáncer/genética , Línea Celular Tumoral , Gonadotropina Coriónica Humana de Subunidad beta/genética , Femenino , Orden Génico , Humanos , Activación de Linfocitos/inmunología , Linfocitos/inmunología , Ratones , Neoplasias/genética , Neoplasias/inmunología , Neoplasias/terapia , Proteínas Recombinantes de Fusión/genética , VacunaciónRESUMEN
Because of the connection constraints of quantum devices, the quantum gate cannot operate directly on nonadjacent qubits. Quantum circuit mapping transforms a logical quantum circuit to a circuit that satisfies the connection constraints by adding SWAP gates for nonadjacent qubits. Global and local heuristic reordering strategies are proposed in this paper for quantum circuit mapping over linear nearest neighbor (LNN) architectures, which are one-dimensional topology structures, to reduce the number of SWAP gates added. Experiment results show that the average improvements of the two methods are 13.19% and 15.46%, respectively. In this paper, we consider the quantum circuit mapping problem for linear nearest neighbor (LNN) architectures. We propose a global heuristic qubit reordering optimization algorithm and a local heuristic qubit reordering optimization algorithm. Compared with the other algorithm results, the average improvements of the two methods for quantum cost are 13.19% and 15.46%, respectively. The two methods apply to the realization of quantum circuit neighboring over one-dimensional quantum architectures and can be extended to algorithms that work for other quantum architectures of different topologies.
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Introduction: Rodent outbreak is the main biological disaster in grassland ecosystems. Traditional rodent damage monitoring approaches mainly depend on costly field surveys, e.g., rodent trapping or hole counting. Integrating an unmanned aircraft system (UAS) image acquisition platform and deep learning (DL) provides a great opportunity to realize efficient large-scale rodent damage monitoring and early-stage diagnosis. As the major rodent species in Inner Mongolia, Brandt's voles (BV) (Lasiopodomys brandtii) have markedly small holes, which are difficult to identify regarding various seasonal noises in this typical steppe ecosystem. Methods: In this study, we proposed a novel UAS-DL-based framework for BV hole detection in two representative seasons. We also established the first bi-seasonal UAS image datasets for rodent hole detection. Three two-stage (Faster R-CNN, R-FCN, and Cascade R-CNN) and three one-stage (SSD, RetinaNet, and YOLOv4) object detection DL models were investigated from three perspectives: accuracy, running speed, and generalizability. Results: Experimental results revealed that: 1) Faster R-CNN and YOLOv4 are the most accurate models; 2) SSD and YOLOv4 are the fastest; 3) Faster R-CNN and YOLOv4 have the most consistent performance across two different seasons. Discussion: The integration of UAS and DL techniques was demonstrated to utilize automatic, accurate, and efficient BV hole detection in a typical steppe ecosystem. The proposed method has a great potential for large-scale multi-seasonal rodent damage monitoring.
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Foodborne illnesses caused by Salmonella represent a significant public health problem worldwide. The aim of this study was to establish multiplex PCR (mPCR) for the rapid identification of Salmonella serogroups B, C1, C2, D, and E as well as for the serovars enteritidis and typhimurium. Employing pan-genome analysis and PCR verification, B-rfbJ, C1-9679, C2-pimB, D-rfbJ, E-rfbC, and four genes (SE18636, SE16574, SE2599, and SE13329) were identified as specific target genes for Salmonella serogroups B, C1, C2, D, E, and S. enteritidis, respectively. Thereafter, three novel mPCR assays (one of 3-mPCR and two of 2-mPCR) were successfully developed to identify these bacteria based on the target genes and another S. typhimurium-specific STM4495 gene. The primers targeting C1-9679, C2-pimB, and E-rfbC genes specific to the serogroups C1, C2, and E, respectively, constituted a 3-mPCR, while the other two 2-mPCRs, respectively, consisting primers specific to serogroup D and S. enteritidis (D-rfbJ and SE16574), and serogroup B and S. typhimurium-specific primers (B-rfbJ and STM4495), were also designed. The specificity of each mPCR was further evaluated by using non-target strains. The detection limits of mPCRs were approximately 103-104 CFU mL-1 in pure culture and 104-105 CFU g-1 in spiked chicken meat. In addition, mPCR assays could correctly detect target Salmonella in food samples. These results suggest that specific targets could be mined efficiently through a pan-genome analysis tool, and the novel mPCR assays developed in this study offer a promising technique for rapid and accurate detection of five serogroups of Salmonella (B, C1, C2, D, and E) and two serovars (S. enteritidis and S. typhimurium).
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Reacción en Cadena de la Polimerasa Multiplex , Salmonella enteritidis , Salmonella enteritidis/genética , SerogrupoRESUMEN
BACKGROUND: Fermented milk is beneficial for metabolic disorders, while the underlying mechanisms of action remain unclear. This study explored the benefits and underlying mechanisms of Bifidobacterium longum 070103 fermented milk (BLFM) in thirteen-week high-fat and high-sugar (HFHS) fed mice using omics techniques. METHODS AND RESULTS: BLFM with activated glucokinase (GK) was screened by a double-enzyme coupling method. After supplementing BLFM with 10 mL/kg BW per day, fasting blood glucose, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and leptin were significantly reduced compared with the HFHS group. Among them, the final body weight (BW), epididymal fat, perirenal fat, and brown fat in BLFM group had better change trends than Lacticaseibacillus rhamnosus GG fermented milk (LGGFM) group. The amplicon and metabolomic data analysis identified Bifibacterium as a key gut microbiota at regulating glycolipid metabolism. BLFM reverses HFHS-induced reduction in bifidobacteria abundance. Further studies showed that BLFM significantly reduces the content of 3-indoxyl sulofphate associated with intestinal barrier damage. In addition, mice treated with BLFM improved BW, glucose tolerance, insulin resistance, and hepatic steatosis. CONCLUSION: BLFM consumption attenuates obesity and related symptoms in HFHS-fed mice probably via the modulation of gut microbes and metabolites.
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Bifidobacterium longum , Microbioma Gastrointestinal , Trastornos del Metabolismo de los Lípidos , Animales , Bifidobacterium longum/metabolismo , Glucemia , LDL-Colesterol/metabolismo , Dieta Alta en Grasa/efectos adversos , Glucoquinasa/metabolismo , Glucosa/metabolismo , Glucolípidos , Leptina/metabolismo , Metabolismo de los Lípidos , Ratones , Ratones Endogámicos C57BL , Leche/metabolismoRESUMEN
Bifidobacterium, an important genus for human health, is difficult to isolate. We applied metagenomics, pangenomics, and enzymology to determine the dominant glycoside hydrolase (GH) families of Bifidobacterium and designed selective medium for Bifidobacterium isolation. Pangenomics results showed that the GH13, GH3, GH42, and GH43 families were highly conserved in Bifidobacterium. Metagenomic analysis of GH families in human faecal samples was performed. The results indicated that Bifidobacterium contains core GHs for utilizing raffinose, D-trehalose anhydrous, D(+)-cellobiose, melibiose, lactulose, lactose, D(+)-sucrose, resistant starch, pullulan, xylan, and glucan. These carbohydrates as the main carbon sources were applied for selective media, which were more conducive to the growth of bifidobacteria. In the medium with lactose, raffinose and xylan as the main carbon sources, the ratio of cultivable bifidobacteria to cultivable microorganisms were 89.39% ± 2.50%, 71.45% ± 0.99%, and 53.95% ± 1.22%, respectively, whereas the ratio in the ordinary Gifu anaerobic medium was only 17.90% ± 0.58%. Furthermore, the species significantly (p < 0.05) varied among samples from different individuals. Results suggested that xylan might be a prebiotic that benefits host health, and it is feasible to screen and isolate bifidobacteria using the oligosaccharides corresponding to the specific GHs of bifidobacteria as the carbon sources of the selective media.
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Salmonella is a widely distributed foodborne pathogen. The use of Salmonella phages as biocontrol agents has recently gained significant interest. Because the Salmonella genus has high diversity, efforts are necessary to identify lytic Salmonella phages focusing on different serovars. Here, five Salmonella phages were isolated from soil samples, and vB_SalP_TR2 was selected as a novel phage with high lytic potential against the host Salmonella serovar Albany, as well as other tested serovars, including Corvallis, Newport, Kottbus, and Istanbul. Morphological analyses demonstrated that phage vB_SalP_TR2 belongs to the Podoviridae family, with an icosahedral head (62 ± 0.5 nm in diameter and 60 ± 1 nm in length) and a short tail (35 ± 1 nm in length). The latent period and burst size of phage vB_SalP_TR2 was 15 min and 211 PFU/cell, respectively. It contained a linear dsDNA of 71,453 bp, and G + C content was 40.64%. Among 96 putative open reading frames detected, only 35 gene products were found in database searches, with no virulence or antibiotic resistance genes being identified. As a biological control agent, phage vB_SalP_TR2 exhibited a high temperature and pH tolerance. In vitro, it lysed most S. Albany after 24 h at 37°C with multiplicities of infection of 0.0001, 0.001, 0.01, 0.1, 1, 10, and 100. In food matrices (milk and chicken meat), treatment with phage vB_SalP_TR2 also reduced the number of S. Albany compared with that in controls. These findings highlighted phage vB_SalP_TR2 as a potential antibacterial agent for the control of Salmonella in food samples.
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BACKGROUND AND AIMS: Aging-induced bone loss is a multifactorial, age-related, and progressive phenomenon among the general population and may further progress to osteoporosis and increase the risk of fractures. Cycloastragenol (CAG), currently the only compound reported that activates human telomerase, is thought to be able to alleviate or delay the symptoms of aging and chronic diseases. Previous research has suggested that CAG may have the potential to alleviate age-related bone loss. However, to date, no research has specifically focused on this aspect. In this study, we aimed to investigate whether CAG could prevent senile osteoporosis, and further reveal its underlying mechanism. METHODS: CAG treatment was administrated into two bone loss rat models (D-galactose administration and aging) for 20 weeks and 33 weeks, respectively. Serum biomarkers analyses, bone biomechanical tests, micro-computed tomography assessment, and bone histomorphometry analyses were performed on the bone samples collected at the endpoint, to determine whether CAG could prevent or alleviate age-related bone loss. Proteomic analysis was performed to reveal the changes in protein profiles of the bones, and western blot was used to further verify the identity of the key proteins. The viability, osteoblastic differentiation, and mineralization of MC3T3-E1 cells were also evaluated after CAG treatment in vitro. RESULTS: The results suggest that CAG treatment improves bone formation, reduces osteoclast number, alleviates the degradation of bone microstructure, and enhances bone biomechanical properties in both d-galactose- and aging-induced bone loss models. CAG treatment promotes viability, osteoblastic differentiation, and mineralization in MC3T3-E1 cells. Proteomic and western blot analyses revealed that CAG treatment increases osteoactivin (OA) expression to alleviate bone loss. CONCLUSION: The results revealed that CAG alleviates age-related bone loss and improves bone microstructure and biomechanical properties. This may due to CAG-induced increase in OA expression. In addition, the results support preclinical investigations of CAG as a potential therapeutic medicine for the treatment of senile osteoporosis.
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Conservadores de la Densidad Ósea/farmacología , Remodelación Ósea/efectos de los fármacos , Fémur/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteoporosis/prevención & control , Sapogeninas/farmacología , Células 3T3 , Factores de Edad , Animales , Modelos Animales de Enfermedad , Femenino , Fémur/metabolismo , Fémur/patología , Galactosa , Masculino , Glicoproteínas de Membrana/metabolismo , Ratones , Osteoclastos/metabolismo , Osteoclastos/patología , Osteoporosis/inducido químicamente , Osteoporosis/metabolismo , Osteoporosis/patología , Ratas Sprague-Dawley , Regulación hacia ArribaRESUMEN
Ultrasound-assisted extraction (UAE) of total monoterpene glycosides extract (TMGE) from oil peony seed cakes was investigated. The extraction yield was optimized using response surface methodology (RSM). The chemical constituents of the monoterpene glycosides extract were isolated by repeated column chromatography, and the contents of the main isolated monoterpene glycosides in the oil peony seed cakes were determined by HPLC. The optimum conditions were as follows: a liquid-to-solid ratio of 27 mL/g, ultrasonic extraction time of 16 min, ultrasonic extraction temperature of 26 °C, and ethanol concentration of 67%. Under these conditions, the extraction yield of TMGE was 10.24%. Twenty monoterpene glycosides were isolated from the oil peony seed cakes, and compounds 11-12, 16 and 20 showed strong inhibitory activities on NO production. TMGE from oil peony seed cakes can also to be used as promising immunosuppressive drug due to its high content of monoterpene glycosides and immune-inhibitory activity. PRACTICAL AAPPLICATION: The peony seed oil was authorized as a new food by the Ministry of Health of the People's Republic of China. Peony seed cake is one of the most important by-products in the preparation of peony seed oil, and accounts for approximately 40% of the total mass of the peony seed. Total monoterpene glycosides are the main active ingredient of oil peony seed cake. This research has optimized the extraction conditions of total monoterpene glycoside from seeds cake of Paeonia ostii, which will provide useful reference information for further studies, and offer related industries with helpful guidance in practice.
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Glicósidos/aislamiento & purificación , Monoterpenos/aislamiento & purificación , Paeonia/química , Aceites de Plantas/química , Semillas/química , Animales , China , Cromatografía Líquida de Alta Presión , Manipulación de Alimentos , Ratones , Modelos Teóricos , Estructura Molecular , Óxido Nítrico/análisis , Células RAW 264.7 , Temperatura , UltrasonidoRESUMEN
A new and practical laboratory approach to synthesize mannose modified chitosan (Man-chitosan) was developed via reductive amination reaction. Chitosan and mannose were used as raw materials. The reaction condition was mild and controllable. The overall yield was 47-52%. Each reaction products and Man-chitosan were characterized by (1)H NMR, ESI-MS, FT-IR and TGA spectrum. FT-IR and (1)H NMR results showed that mannose conjugated to chitosan via an alkane chain bridge (CH(2)CH(2)). The degree of substitution was calculated by element analysis. TGA results indicated that mannose grafted to chitosan slightly decreased the thermal stability of chitosan in some extent. MTT assay indicated that Man-chitosan was low cytotoxicity against HepG-2 and SMMC-7721 cells.
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Técnicas de Química Sintética/métodos , Quitosano/química , Quitosano/síntesis química , Manosa/química , Supervivencia Celular/efectos de los fármacos , Quitosano/toxicidad , Células Hep G2 , Humanos , Análisis Espectral , TemperaturaRESUMEN
P277 is a peptide derived from the HSP60 regions, have potent immunological effect on insulin-dependent diabetes mellitus (IDDM) and its phase III clinical trials are currently under investigation. However, we recently discovered a positive correlation between anti-P277 autoantibodies and the presence of endothelial cells damage in inducing vascular leak syndrome. Therefore, the aim of our study was to demonstrate the critical peptide epitope of P277 to IDDM and to highlight the effects of this peptide therapy on inflammation of the islets. Groups of 4-week old female non-obese diabetic (NOD) mice were immunized one time every three weeks for three times with a residue of P277, showing a significant effect of down-regulating immunity to P277 protein and preventing the development of IDDM. Immunologic results including the suppression of T-cell proliferation, the increase of interleukin-10 (IL-10) production and reduction of interferon-γ (IFN-γ) production caused immune tolerance to P277. Hence, a functional role of the key epitope in P277 peptide capable of preventing IDDM is suggested, which could be modified to develop a novel safe and effective peptide vaccine against IDDM by reconstructing P277 in the further studies.