ABSTRACT
Cholesterol (CHOL) is an important clinical biochemical indicator that plays an important role in the regulation of the fluidity, permeability, and microstructure of cell membranes. Therefore, it is necessary to accurately monitor CHOL levels in biological samples for the early prevention and diagnosis of various diseases. The single-band red upconversion nanoparticle (UCNP) emits light within the optical transmission window of biological tissues, and can penetrate deeper biological tissues and cause less energy loss due to scattering and thus have higher sensitivity and accuracy. Here, using the nontoxic, sensitive, and photochemically stable 3,3',5,5'-tetramethylbenzidine (TMB) as the quenching agent and single red UCNP as the fluorescent donor, a dual-readout colorimetric and fluorescent sensor was developed to detect CHOL. The detection mechanism and feasibility were discussed in detail, and experimental conditions such as Fe2+ concentration, TMB concentration and reaction time were explored. Under optimal conditions, the limits of CHOL detection by colorimetry and fluorescence were 0.85 µM and 0.63 µM. The sensing system was used to measure CHOL in serum samples and the values obtained by these two modes were close, and the spiked recoveries were 97.2-102.2% and 97.1-103.7%, respectively, which holds great potential in clinical diagnosis and health management.
ABSTRACT
OBJECTIVE To investigate the improvement effect and mechanism of calycosin （CA） on acute inflammatory injury secondary to intracerebral hemorrhage. METHODS Male C57BL/6 mice were injected with type Ⅶ collagenase into the basal ganglia to establish an intracerebral hemorrhage model， which were divided into sham-operation group（phosphate buffered saline instead of collagenase）， model group， and different CA dose groups（15，30，60，120 mg/kg）. Based on the modified neurological severity score （mNSS） to screen the intervention doses， the volume of intracerebral hemorrhage， brain water content， the expressions of ionized calcium-binding adaptor molecule 1 （Iba1） in brain tissue， Toll-like receptor 4 （TLR4） and its downstream inflammatory factors [tumor necrosis factor-α （TNF-α）， inducible nitric-oxide synthase （iNOS）， interleukin-1β （IL- 1β）] in brain tissue， and the apoptosis of cells in brain tissue were detected. Primary microglia were cultured in vitro， and the expressions of TLR4 and its downstream inflammatory factors were detected. Primary neurons and primary microglia were co- cultured in vitro， and the apoptosis of neurons was detected. RESULTS The doses of 30 mg/kg and 60 mg/kg were selected as intervention doses of CA for subsequent experiments. Compared with the sham-operation group， the mice in the model group had cerebral hemorrhage， the volume of cerebral hemorrhage and brain water content were significantly increased （P＜0.05）； the positive expression rate of Iba1 protein in brain tissue was significantly increased， and the relative expression levels of TLR4， TNF-α， IL-1β and iNOS protein in brain tissue were up-regulated significantly. The apoptosis rate also increased significantly （P＜0.05）. Compared with model group， the above indexes of the mice in the 30 and 60 mg/kg CA groups were significantly improved （P＜0.05）. CA significantlyreduced the relative expression levels of TLR4 and its downstream inflammatory factors in microglia， and reduced the apoptosis of neurons in the co-culture system of primary neurons and primary microglia （P＜0.05）. CONCLUSIONS CA can exert a protective effect on the brain， which may be related to relieving the secondary acute inflammatory injury after intracerebral hemorrhage by inhibiting TLR4-mediated inflammatory response.
ABSTRACT
OBJECTIVE:The preparation of microspheres was optimized by central composite design in order to improve the lung targeting of tetrandrine chitosa microspheres. METHODS:Microspheres were prepared using an emulsion-chemical crosslink technique.Effects of three independent variables i.e. weight percent of tetrandrine and christon, volume percent of water phase and organic phase and christon concentration in aqueous phase were investigated on four response variables.Response variables selected in the research were yield,drug loading, envelop efficiency, mean diameter and span of dispersity.Second-order polynomial and linear equations were fitted to the data,and the resulting equations were used to produce three dimensional response surface graphs,by which optimal experimental conditions were selected. RESULTS:Five response variables were found to be dependent on three independent variables. According to optimal experimental conditions.An optimized formulation contained weight percent of tetrandrine and christon was 61.97%, volume percent of water phase and organic phase was 13.51% and christon concentration in aqueous phase was 2.37%. CONCLUSION:The central composite design can be used to optimazation of preparation formulation,diameter of the microspheres optimized by it can meet the demands of lung-targeting.
