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In situ tailoring of two-dimensional materials' phases under external stimulus facilitates the manipulation of their properties for electronic, quantum and energy applications. However, current methods are mainly limited to the transitions among phases with unchanged chemical stoichiometry. Here we propose on-device phase engineering that allows us to realize various lattice phases with distinct chemical stoichiometries. Using palladium and selenide as a model system, we show that a PdSe2 channel with prepatterned Pd electrodes can be transformed into Pd17Se15 and Pd4Se by thermally tailoring the chemical composition ratio of the channel. Different phase configurations can be obtained by precisely controlling the thickness and spacing of the electrodes. The device can be thus engineered to implement versatile functions in situ, such as exhibiting superconducting behaviour and achieving ultralow-contact resistance, as well as customizing the synthesis of electrocatalysts. The proposed on-device phase engineering approach exhibits a universal mechanism and can be expanded to 29 element combinations between a metal and chalcogen. Our work highlights on-device phase engineering as a promising research approach through which to exploit fundamental properties as well as their applications.
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Poria is an important medical herb in clinic. The authors isolated a polysaccharide(PCP-â ) from Poria in previous studies, which is composed of galactose, mannose, fucose and glucose. PCP-â exhibited significant adjuvant effects on H1N1 influenza vaccine, hepatitis B surface antigen and anthrax protective antigen, and its adjuvant activity was stronger than aluminium adjuvant. However, little is known about the chemical structure of PCP-â at present. In this study, weak acid hydrolysis was used to obtain the backbone oligosaccharide of PCP-â . Then periodate oxidation, Smith degradation, methylation analysis, Fourier transform infrared spectroscopy(FT-IR), nuclear magnetic resonance(NMR) and gas chromatography-mass spectrometry(GC-MS) were performed to investigate the chemical structural features of PCP-â and its hydrolytic oligosaccharide(PCP-â -hy-1). These results suggested that the backbone of PCP-â was composed of galactose with α anomeric carbon and ß anomeric carbon. The linking residues of galactan are(1â),(lâ6) and(1â2,6).
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Subtipo H1N1 del Virus de la Influenza A , Poria , Adyuvantes de Vacunas , Hidrólisis , Espectroscopía Infrarroja por Transformada de Fourier , Galactosa , Polisacáridos/química , Oligosacáridos , CarbonoRESUMEN
Ring piezoelectric transducers (rPETs) have attracted multitudinous attentions due to their widespread applications in hydro-acoustic engineering, structural health monitoring, and energy harvesting. However, cracks are inevitably occurred by the concentrated stress at the interface between metal and piezoelectric ceramics, which will seriously affect the performance and service life of the devices. Hence, a novel functionally graded ring piezoelectric transducer (FG-rPET) has been designed and an accurate analytical system is constructed mainly including a three-port electromechanical equivalent circuit model (EECM) which can acquire exact solutions in radial vibration. In addition, the proposed three-port EECM has excellent generalizability, which is also applicable to conventional rPETs. The validity of the EECM is verified by experiments and the finite element method. The vibration characteristics (resonance/anti-resonance frequencies and effective electromechanical coupling coefficient (keff)) with fundamental and second modes for the FG-rPETs can be regulated via the inhomogeneity index and wall thickness. Markedly enhanced keff at second modes can be obtained for the FG-rPETs with specific wall thicknesses. The proposed analytical system has important guiding significance for structure optimization design of piezoelectric devices, and the designed FG-rPET is expected to break the bottleneck of mechanical properties for the conventional rPETs.
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A new iso-C14 [Val2, Val7] surfactin isoform (1) together with eight known ones (2-9), was isolated from the culture of a mushroom derived bacterium, Bacillus halotolerans DMG-7-2. The structures of them were mainly elucidated by NMR and MS data, and the NMR data of 5 also was reported for the first time. The absolute configuration of 1 was determined by Marfey's analysis (for amino acid residues) and the 13C NMR calculation of the two plausible epimers of 1 (for fatty acid). Compounds 1-9 showed moderate cytotoxicity against two human cancer cell lines (A549, MCF-7) and mice microglial BV2 cells, the IC50 values ranged from 8.91 to 33.00 µM, and the IC50 values of the positive control 5-FU were 99.94, 71.49 and 0.12 µM, respectively.[Formula: see text].
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Agaricales , Aminoácidos , Animales , Bacillus , Ácidos Grasos , Fluorouracilo , Humanos , Ratones , Isoformas de ProteínasRESUMEN
OBJECTIVE: To investigate the chemical characters of water-extract of Baqi Lingmao formula (BQLM formula) and its effects on anti-liver injury in model mice and live cells. METHODS: BQLM formula was composed of ten herbal medicines. We determined the contents of alkaloids, saponins, phenolic acids and flavonoid in BQLM formula by UV spectrophotometry. The active components of alkaloids and phenolic acids in BQLM formula were identified by HPLC chromatography. The anti-hepatic injury effects of BQLM formula were investigated with concanavalin A (ConA)-induced hepatitis model of mice, human liver LO2 and HepG2.2.15 cells. RESULTS: BQLM formula (2 and 10 g/kg, orally) significantly improved the damages of liver tissues and functions caused by ConA in mice, reduced the infiltration of inflammatory cells into liver and inhibited the inflammatory cytokine secretion of interferon-γ, tumor necrosis factor-α and interleukin-6. BQLM formula simultaneously decreased the levels of alanine aminotransferase and aspartate aminotransferase of liver and serum, and recovered the superoxide dismutase and catalase activities of liver to normal levels in ConA-induced hepatic-injury mice. The serum of BQLM formula group stimulated the human liver LO2 cell proliferation in vitro. Further, BQLM formula obviously promoted the proliferation of normal hepatocytes (LO2 cells) and inhibited the hepatocytes death induced by ConA. It also significantly inhibited the proliferation of HepG2.2.15 cells and decreased the secretion of HBsAg and HBeAg in vitro. CONCLUSIONS: BQLM formula has anti-inflammation and anti-hepatitis virus Beffects, and is capable of improving liver injury in vivo and in vitro.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Animales , Aspartato Aminotransferasas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Concanavalina A , Hepatocitos/metabolismo , Hepatocitos/patología , Hígado , RatonesRESUMEN
Cascaded-piezoelectric-transducers (CPETs) is a key component in modern energy-conversion fields, possessing versatile applications in ultrasonic scalpels, acoustic levitation, and sonar. However, serious self-heating inevitably occurs inside high-power CPETs, severely limiting their practical applications in broader fields. To tackle this, multidirectional heat-escape channels of multidimensional (multi-D, 3D/2D) graphene films are introduced in designing new-type thermal regulators. A porous AlN-ceramic thermal-sink is creatively selected as a template for directly synthesizing graphene via a two-step chemical vapor deposition strategy. This perfect combination of 3D/2D-graphene and the AlN ceramic can integrate their complementary advantages in uniformizing, transmitting, and releasing heat. Amazingly, in the new-generation CPETs embedded with these graphene-based thermal regulators, the self-heating-induced temperature rise can be substantially reduced by ≈60% (far exceeding actual demand standard). As another kernel parameter, electroacoustic-energy-conversion efficiency is dramatically improved in the new-generation CPETs. Briefly, this research realizes the first synthesis of a novel multi-D-graphene/AlN-ceramic hybrid, and propels its brand-new application directions in new-generation energy-conversion- and thermal-management-related territories.
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Improving the adhesion property of graphene directly grown on an insulating substrate is essential for promoting the reliability and durability of the related applications. However, effective approaches have rarely been reported, especially for vertically oriented graphene (VG) films grown on insulating templates. To tackle this, we have developed a facile synthetic strategy by introducing an ultrathin (10 nm-thick) titanium (Ti) film on a quartz glass substrate as the adhesion layer, for plasma-enhanced chemical vapor deposition (PECVD) growth of VG films. This synthetic process induces the formation of Ti, oxygen (O), carbon (C)-containing adhesion layer (Ti (O, C)), offering improved interfacial adhesion due to the formation of chemical bonds among Ti and C atoms. Dramatically improved surface and interface stabilities have been achieved, with regard to its counterpart without a Ti adhesion layer. Moreover, we have also realized precise controls of the transparent/conductive property, surface roughness, and hydrophobicity, etc., by varying the VG film growth time. We have also demonstrated the very intriguing application potentials of the hybrids in light-dimming related fields, that is, electro-heating defogging lenses and neutral density filters toward medical endoscope defogging and camera photography.
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Five new peptaibols, longibramides A-E (1-5) with 11 amino acid residues, were isolated from a fungus Trichoderma longibrachiatum Rifai DMG-3-1-1, which was isolated from a mushroom Clitocybe nebularis (Batsch) P. Kumm collected from coniferous forest in the subboreal area of northeast China. The structures of longibramides A-E were determined by their spectroscopic data (NMR and MS-MS spectra), their absolute configurations were determined by X-ray diffractions and Marfey's analyses. The X-ray diffractions of longibramides A, B, and the similar CD spectra of A-E showed that they all had α-helix conformations. Longibramides B and E showed moderate cytotoxicities against BV2 and MCF-7 cells and also showed some inhibitory effects against methicillin-resistant Staphylococcus aureus MRSA T144. L-trans-Hyp was not commonly found in natural peptaibols, which was the 6th or 10th amino acid residue in longibramides C-E. The X-ray diffractions of longibramides A and B afforded the accuracy conformations of their secondary structures, which maybe help to interpret the structure-activity relationships of the family of peptaibols in the future.
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Agaricales/química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Peptaiboles/farmacología , Trichoderma/química , Antibacterianos , Antineoplásicos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Conformación Molecular , Peptaiboles/química , Peptaiboles/aislamiento & purificaciónRESUMEN
The direct growth of vertically oriented graphene (VG) on low-priced, easily accessible soda-lime glass can propel its applications in transparent electrodes and energy-relevant areas. However, graphene deposited at low temperature (â¼600 °C) on the catalysis-free insulating substrates usually presents high defect density, poor crystalline quality, and unsatisfactory electrical conductivity. To tackle this issue, we select high borosilicate glass as the growth substrate (softening point â¼850 °C), which can resist higher growth temperature and thus afford higher graphene crystalline quality, by using a radio-frequency plasma-enhanced chemical vapor deposition (rf-PECVD) route. A nitrogen doping strategy is also combined to tailor the carrier concentration through a methane/acetonitrile-precursor-based synthetic strategy. The sheet resistance of as-grown nitrogen-doped (N-doped) VG films on high borosilicate glass can thus be lowered down to â¼2.3 kΩ·sq-1 at a transmittance of 88%, less than half of the methane-precursor-based PECVD product. Significantly, this synthetic route allows the achievement of 30-inch-scale uniform N-doped graphene glass, thus promoting its applications as excellent electrodes in high-performance switchable windows. Additionally, such N-doped VG films were also employed as efficient electrocatalysts for electrocatalytic hydrogen evolution reaction.
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Ultrasonic transducers with large output power have attracted extensive attentions due to their widespread applications in sonar, acoustic levitation, ultrasonic focusing, and so forth. However, the traditional transducer has almost no heat-dissipation capability itself, strictly relying on the assistant coolant system. Introducing high-performance heat-dissipation component is thus highly necessary. Herein, an embedded porcelain radiator component was designed by combining the excellent thermal conductivity of vertically oriented graphene (VG) with the outstanding heat-dissipation characteristics of thermosensitive ceramics, and a new-type transducer with an embedded VG/ceramic-hybrid radiator was constructed to show high heat-dissipation efficiency (up to â¼5 °C/min). Remarkably, prominent heat-dissipation effectiveness (temperature decline of â¼12 °C), enhanced amplitude and vibration uniformity were also achieved for the new-type transducer along with stabilized operating states. This research should pave ways for extending the applications of VG/ceramic hybrids to heat-dissipation scenarios and provide newfangled thoughts for the performance upgrade of multitudinous high-power devices.
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Direct growth of vertically oriented graphene (VG) nanowalls on soda-lime glass has practical significance in extending the application of graphene to daily-life-related areas, such as gas sensors and conductive electrodes, via combining their complementary properties and applications. However, VG films derived by low-temperature deposition (e.g., on glass) usually present relatively low conductivity and optical transparency. To tackle this issue, an ethanol-precursor-based, radio-frequency plasma-enhanced chemical vapor deposition (rf-PECVD) route for the synthesis of VG nanowalls is developed in this research, at around the softening temperature of soda-lime glass (â¼600 °C) templates. The average sheet resistance, i.e., â¼2.4 kΩ·sq-1 (at transmittance â¼81.6%), is only one-half of that achieved by a traditional methane-precursor-based PECVD route. Based on the highly conductive and optically transparent VG/glass, as well as its scalable size up to 25 in. scale, high-performance reversible thermochromic devices were successfully constructed using VG/glass as transparent heaters. Hereby, this work should propel the scalable synthesis and applications of highly conductive VG films on glass in next-generation transparent electronics and switchable windows.
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Polysaccharides isolated from natural plants may represent a novel source of vaccine adjuvants. In this research, we focused on a natural plant polysaccharide, PCP-I, which is derived from Poria cocos, a Chinese traditional herbal medicine. We chose the anthrax protective antigen (PA) as a model to evaluate the adjuvant ability of PCP-I in enhancing the immunogenicity and protection of a PA-based anthrax vaccine. According to our results, PCP-I could significantly enhance anthrax specific anti-PA antibodies, toxin-neutralizing antibodies, anti-PA antibody affinity, as well as IgG1 and IgG2a levels. Besides, PCP-I increased the frequency of PA-specific memory B cells, increased the proliferation of PA-specific splenocytes, significantly stimulated the secretion of IL-4, and enhanced the activation of Dendritic cells (DCs) in vitro. The combination of PCP-I and CpG significantly enhanced the level of anti-PA antibodies and neutralizing antibodies, particularly PA-specific IgG2a, and shifted the Th2-bias to a Th1/Th2 balanced response. In addition, PCP-I with or without CpG could significantly improve the survival rate of immunized mice following challenge with the anthrax lethal toxin. These findings suggest that PCP-I may be a promising vaccine adjuvant that warrants further study.
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Vacunas contra el Carbunco , Carbunco , Bacillus anthracis , Wolfiporia , Animales , Carbunco/prevención & control , Anticuerpos Antibacterianos , Antígenos Bacterianos , Toxinas Bacterianas , Ratones , Ratones Endogámicos BALB C , PolisacáridosRESUMEN
The medicinal plant Morinda officinalis How and its root have long been used in traditional medicines in China. The aims of the present study were to investigate the chemical composition and liver-protective effect of crude polysaccharides (MOP-100) from the processed root of Morinda officinalis against Concanavalin A (ConA)-induced liver damage in vivo and vitro. The processed root of the herbal medicine was extracted with water at 100⯰C, then precipitated with ethanol, dialyzed and freeze-dried to obtain MOP-100. The molecular weight of MOP-100 was a wide distribution. However, the processed root was extracted consecutively at 60⯰C and 100⯰C to obtain two crude polysaccharides MOP-60 and MOP-60-100. MOP-60 mainly contained an inulin-type fructooligosaccharide with molecular weight of 2071â¯Da. MOP-100 significantly inhibited the infiltration of neutrophils and macrophages into liver, improved the hepatic injury induced by ConA in mice. It stimulated the proliferation of human liver LO2 cells and decreased the cell death induced by ConA. MOP-100 also significantly inhibited the HBeAg secretion of Hep2.5.5 hepatocytes in vitro. MOP-60 and MOP-60-100 both exhibited good activity of protecting hepatocytes against ConA-induced damage in vitro. These results suggested Morinda officinalis polysaccharides exert significant hepatoprotective effect, and it might be used for treatment of immune-mediated liver disease in the future.
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Inulina , Hepatopatías/tratamiento farmacológico , Hígado/metabolismo , Morinda/química , Raíces de Plantas/química , Sustancias Protectoras , Línea Celular , Humanos , Inulina/química , Inulina/aislamiento & purificación , Inulina/farmacología , Hígado/patología , Hepatopatías/metabolismo , Hepatopatías/patología , Sustancias Protectoras/química , Sustancias Protectoras/aislamiento & purificación , Sustancias Protectoras/farmacologíaRESUMEN
Adjuvants are important components of vaccination strategies because they boost and accelerate the immune response. The aim of this study was to investigate the adjuvant activity of PCP-II, a polysaccharide isolated from Poria cocos, together with an inactivated rabies vaccine. The polysaccharide PCP-II was compared with the common veterinary rabies vaccine adjuvant Alhydrogel by co-administration of either adjuvant with the inactivated rabies virus rCVS-11-G to mice via the intramuscular route. Blood samples were collected to determine the virus-neutralizing antibody (VNA) titer and assess activation of B and T lymphocytes. Inguinal lymph node samples were collected, and proliferation of B lymphocytes was measured. Splenocytes were isolated, and antigen-specific cellular immune responses were evaluated by enzyme-linked immunospot and immunosorbent assays (ELISpot assay and ELISA, respectively). The results showed that PCP-II enhanced and promoted an increase in the VNA titer in the mice compared to Alhydrogel. Flow cytometry assays revealed that the polysaccharide activated more B lymphocytes in the lymph nodes and more B and T lymphocytes in the blood. Assessment of antigen-specific cellular immune responses showed that PCP-II strongly induced T lymphocyte proliferation in the spleen and high levels of cytokine secretion from splenocytes. All of these data suggest that PCP-II possesses excellent adjuvant activity and enhances both cellular and humoral immunity in mice. After examining the adjuvant activities of PCP-II in mice, dogs were immunized with rCVS-11-G together with Alhydrogel or PCP-II as an adjuvant; the control group was injected with a commercial rabies vaccine. Serum samples were collected, and the VNA titers were measured. PCP-II caused increases in the VNA titers in both the booster and single-dose immunization tests when co-administered with rCVS-11-G compared with Alhydrogel. The VNA titer of the commercial vaccine group was also significantly lower than that of the PCP-II group. These data indicate that PCP-II is an excellent candidate adjuvant for inactive rabies vaccines in the veterinary setting.
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Adyuvantes Inmunológicos/química , Anticuerpos Antivirales/sangre , Polisacáridos Fúngicos/inmunología , Vacunas Antirrábicas/inmunología , Rabia/prevención & control , Wolfiporia/química , Adyuvantes Inmunológicos/administración & dosificación , Animales , Anticuerpos Neutralizantes/sangre , Citocinas/inmunología , Perros , Femenino , Polisacáridos Fúngicos/administración & dosificación , Inmunidad Celular , Ratones , Ratones Endogámicos BALB C , Vacunas Antirrábicas/administración & dosificación , Virus de la Rabia , Vacunación , Vacunas de Productos Inactivados/inmunologíaRESUMEN
In recent years, molybdenum disulfide (MoS2) based field-effect transistors (FETs) have attracted much attention because of the unique properties of MoS2 nano-materials as an ideal channel material. Using a MoS2 FET as a glucose solution biosensor has the advantages of high sensitivity and rapid response. This paper is concerned with the fabrication of a bilayer MoS2-based FET and the study of its application in the high sensitivity detection of an extremely low concentration glucose solution. It was found that the source-drain current (I ds) increases as the concentration of the glucose solution increases at the same gate voltage (V gs) and drain voltage (V ds). The sensitivity of the biosensor as high as 260.75 mA mM-1 has been calculated and the detection limit of 300 nM was measured. The unknown concentration of a glucose solution was also detected using data based on the relationship between I ds and glucose solution concentration. In addition, many significant advantages of the biosensor were observed, such as short response time (<1 s), good stability, wide linear detection range (300 nM to 30 mM) and the micro-detection of glucose solutions. These unique properties make the bilayer MoS2-based FET a great potential candidate for next generation biosensors.
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Roots of Sophora flavescens is an important herbal medicine for treatment of HBV and hepatic carcinoma in China. Alkaloids in the root were well known for exhibiting good hepato-protective and anti-HBV effects. However, polysaccharides as main components in the root remained unknown. In the studies, we investigated the chemical features and hepatoprotective effects of Sophora flavescens polysaccharides (SFP-100 and its active fractions) with ConA-induced hepatitis mice, human liver LO2 cells and HepG2.2.15 cells. The results showed that SFP-100 was composed of arabinose, glucose, galactose and galacturonic acid, SFP-100-A mainly contained glucose. SFP-100-B and SFP-100-C were acidic polysaccharides. SFP-100 significantly decreased hepatocytes apoptosis, inhibited the infiltration of neutrophils and macrophages into liver, and improved the production of IFN-γ and IL-6 of splenocytes in ConA-induced hepatitis mice. SFP-100 and its two sugar fractions increased LO2 cell proliferation and reduced cell apoptosis induced by ConA. SFP-100, SFP-100-A and SFP-100-C remarkedly inhibited the secretion of HBsAg and HBeAg by HepG2.2.15 cells.These results suggested Sophora flavescens polysaccharides exerts significant hepatoprotective and anti-HBV roles, and further is used for treatment of immune-mediated liver disease in the future.
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Antivirales/farmacología , Virus de la Hepatitis B/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Extractos Vegetales/farmacología , Raíces de Plantas/química , Polisacáridos/farmacología , Sustancias Protectoras/farmacología , Sophora/química , Animales , Antivirales/química , Peso Corporal , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Concanavalina A/efectos adversos , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Hepatitis B/tratamiento farmacológico , Hepatitis B/patología , Hepatitis B/virología , Hepatocitos/virología , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Linfocitos/metabolismo , Ratones , Tamaño de los Órganos , Extractos Vegetales/química , Polisacáridos/química , Sustancias Protectoras/químicaRESUMEN
BACKGROUND: Marburg virus (MARV) causes severe haemorrhagic fever in humans and nonhuman primates and has a high mortality rate. However, effective drugs or licensed vaccines are not currently available to control the outbreak and spread of this disease. METHODS: In this study, we generated MARV virus-like particles (VLPs) by co-expressing the glycoprotein (GP) and matrix protein (VP40) using the baculovirus expression system. MARV VLPs and three adjuvants, Poria cocos polysaccharide (PCP-II), poly(I:C) and aluminium hydroxide, were evaluated after intramuscular vaccination in mice. RESULTS: Murine studies demonstrated that vaccination with the MARV VLPs induce neutralizing antibodies and cellar immune responses. MARV VLPs and the PCP-II adjuvant group resulted in high titres of MARV-specific antibodies, activated relatively higher numbers of B cells and T cells in peripheral blood mononuclear cells (PBMCs), and induced greater cytokine secretion from splenocytes than the other adjuvants. CONCLUSION: MARV VLPs with the PCP-II adjuvant may constitute an effective vaccination and PCP-II should be further investigated as a novel adjuvant.
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Glicoproteínas/inmunología , Enfermedad del Virus de Marburg/prevención & control , Marburgvirus/inmunología , Vacunas de Partículas Similares a Virus/inmunología , Proteínas de la Matriz Viral/inmunología , Vacunas Virales/inmunología , Adyuvantes Inmunológicos , Animales , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Linfocitos B/inmunología , Citocinas/sangre , Citocinas/metabolismo , Expresión Génica , Glicoproteínas/genética , Inmunidad Celular , Marburgvirus/genética , Ratones , Células Sf9 , Linfocitos T/inmunología , Vacunas de Partículas Similares a Virus/genética , Vacunas de Partículas Similares a Virus/ultraestructura , Proteínas de la Matriz Viral/genética , Vacunas Virales/genéticaRESUMEN
Our previous studies found that the crude polysaccharides (IJP) from flowers of Inula japonica exhibited significantly anti-diabetic activity in alloxan or MLD-STZ induced diabetic mice. In this study, we will trace an active polysaccharide from IJP and investigate its physico-chemical property and its protective mechanism on islet cell damage. The result showed that an active polysaccharide (IJP-B-1) was isolated from IJP, its molecular mass was 3.7×104Da. IJP-B-1 was composed of rhamnose, arabinose, xylose, mannose, glucose, galactose and galactocuronic acid. Its major backbone structure was (1â3, 6)-linked-galactose and other branched residues. IJP-B-1 could protect pancreatic cells against STZ impairment at 50µg/mL and scavenge OH and O2 radicals to decrease reactive oxygen generation in islet-cells in vitro. These results suggested that IJP-B-1 might be useful for protecting ß-cells and against oxidative stress as an anti-diabetic candidate drug in future.
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Citoprotección/efectos de los fármacos , Flores/química , Células Secretoras de Insulina/efectos de los fármacos , Inula/química , Polisacáridos/química , Polisacáridos/farmacología , Animales , Línea Celular , Radical Hidroxilo/química , Células Secretoras de Insulina/citología , Ratones , Polisacáridos/aislamiento & purificación , Relación Estructura-Actividad , Superóxidos/químicaRESUMEN
Infectious diseases possess a big threat to the livestock industry worldwide. Currently, inactivated veterinary vaccines have attracted much attention to prevent infection due to their safer profile compared to live attenuated vaccine. However, its intrinsic poor immunogenicity demands the incorporation of an adjuvant. Mineral oil based adjuvant (Montanide™ ISA206) was usually used to potentiate the efficacy of veterinary vaccines. However, ISA206 could not induce robust cellular immune responses, which was very important in controlling virus replication and clearing the infected cells. Moreover, mineral oil would result in severe side effects. To improve both the humoral and cellular immune responses of porcine reproductive and respiratory syndrome virus (PRRSV) inactivated vaccine, we developed pH-sensitive and size-controllable quaternized chitosan hydrogel microparticles (Gel MPs) without using chemical cross linking agent. Gel MPs, ionic cross-linked with glycerophosphate (GP), were biocompatible and could efficiently adsorb the inactivated PRRSV vaccine with a loading capacity of 579.05µg/mg. After intramuscular immunization in mice, results suggested that Gel MPs elicited significantly higher cell-mediated immune responses and comparable humoral immune responses compared to ISA 206. Regarding the biocompatibility, safety and effectiveness, Gel MPs would be a promising candidate to enhance the efficacy of veterinary vaccine.
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Adyuvantes Inmunológicos/administración & dosificación , Quitosano/administración & dosificación , Síndrome Respiratorio y de la Reproducción Porcina/inmunología , Virus del Síndrome Respiratorio y Reproductivo Porcino/inmunología , Porcinos , Vacunas de Productos Inactivados/inmunología , Vacunas Virales/inmunología , Animales , Cápsulas , Femenino , Hidrogel de Polietilenoglicol-Dimetacrilato , Inmunidad Celular , Inmunidad Humoral , Inmunización , Ensayo de Materiales , Ratones , Ratones Endogámicos BALB C , Síndrome Respiratorio y de la Reproducción Porcina/prevención & control , Medicina VeterinariaRESUMEN
A water-soluble polysaccharide (named RAP) was newly isolated from the stems of Rubus amabilis. Structural confirmation of the polysaccharide was provided by hydrolysis, periodate oxidation, Smith degradation, and methylation analysis, combined with nuclear magnetic resonance (NMR), capillary electrophoresis (CE), infrared spectroscopy (IR), and gas chromatography-mass spectra (GC-MS). In vitro immunological enhancement activity was characterized using the proliferative activity of spleen lymphocytes and phagocytic activity of peritoneal macrophages in mice. The polysaccharide was mainly composed of xylose, arabinose, glucose, rhamnose, galactose, mannose, glucuronic acid, and galactocuronic acid in the molar ratio of 1.0:6.9:0.8:1.1:6.9:0.3:0.5:3.3, with the average molecular weight of 26.2 kDa. The linkage types of netural monosaccharides were as follows: the arabinose was â2) Ara (1â and galactose were Gal (1â, â3) Gal (1â, â3,6) Gal (1â, â2,3,6) Gal (1â and â2,3,6) Galf (1â. Xyl (1â, â6) Glc (1â, â2) Glc (1â, â3) Rha (1â, Rha (1â and Man (1â were also found in the structure. RAP-B-2 could improve the proliferative activity of spleen T cells and B cells and boost phagocytic activity of peritoneal macrophages at the concentration of 50 µg/ml (p < 0.05, p < 0.01).