ABSTRACT
Protein self-assemblies at the micro- and nano-scale are of great interest because of their morphological diversity and good biocompatibility. High-throughput screening of protein self-assembly at different scales and morphologies using protein crystallization screening conditions is an emerging method. When using this method to screen protein self-assembly conditions, some apparently transparent droplets are often observed, in which it is not clear whether self-assembly occurs. We explored the interaction between β-lactoglobulin and the protein crystallization kit Index™ C10 and observed the presence of micro- and nano-scale protein self-assemblies in the transparent droplets. The diverse morphology of the micro- and nano-scale self-assemblies in the transparent droplets formed by mixing different initial concentrations of β-lactoglobulin and Index™ C10 was further investigated by scanning electron microscope. Self-assembly process of fluorescence-labelled β-lactoglobulin was monitored continuously by laser confocal microscope, allowing real-time observation of the liquid-liquid phase separation phenomenon and the morphology of the final self-assemblies. The internal structure of the self-assemblies was gradually ordered over time by in-situ X-ray diffraction. This indicates that the self-assembly phenomenon within transparent droplets, observed in protein self-assembly condition screening experiments, is worthy of further in-depth exploration.
Subject(s)
Crystallization , LactoglobulinsABSTRACT
Objective@#To prepare a kind of lipid nanoparticle ultrasound contrast agents with the ability to target to viable myocardium for diagnosis.@*Methods@#The agent was a biotinylated, fluorescent-labelled, lipid-coated, liquid perfluorocarbon emulsion. Physico-chemical properties of the agent were measured, including size distribution, Zeta Potential, concentration and so on. Ischemia-reperfusion models were created in rats, and then exposed to biotinylated anti-MCP-1 monoclonal antibody, rhodamine avidin and biotinylated, FITC-labelled nanoparticles, respectively. Echocardiography was taken before and after injection. Frozen sections of their hearts were observed under fluorescence microscope.@*Results@#The particle diameter, zeta potential and concentration of lipid nanoparticles were (172.30±52.06)nm, (-33.10±6.50)mV and (2.28±0.46)×1011/ml, respectively. From the short-axis view, the myocardium under endocardium of anterior wall was enhanced obviously. While myocardium of other walls were still. The lipid nanoparticles located in the myocardium of anterior wall and gave out bright green and red fluorescence under fluorescence microscope, while neither lipid nanoparticles nor fluorescence were found in other sites of ventricular myocardium.@*Conclusions@#The viable myocardium can be targeted and acoustically enhanced by the self-made nano-scale ultrasound contrast agent. This new agent has potential to improve sensitivity and specificity for noninvasive identifying viable myocardium.
ABSTRACT
Objective To prepare a kind of lipid nanoparticle ultrasound contrast agents with the ability to target to viable myocardium for diagnosis . Methods T he agent was a biotinylated ,fluorescent‐labelled ,lipid‐coated , liquid perfluorocarbon emulsion . Physico‐chemical properties of the agent were measured ,including size distribution ,Zeta Potential ,concentration and so on . Ischemia‐reperfusion models were created in rats ,and then exposed to biotinylated anti‐MCP‐1 monoclonal antibody ,rhodamine avidin and biotinylated ,FITC‐labelled nanoparticles ,respectively . Echocardiography was taken before and after injection . Frozen sections of their hearts were observed under fluorescence microscope . Results T he particle diameter ,zeta potential and concentration of lipid nanoparticles were ( 172 .30 ± 52 .06) nm ,( －33 .10 ± 6 .50) mV and ( 2 .28 ± 0 .46 ) × 1011/ml ,respectively . From the short‐axis view ,the myocardium under endocardium of anterior wall was enhanced obviously . While myocardium of other walls were still . T he lipid nanoparticles located in the myocardium of anterior wall and gave out bright green and red fluorescence under fluorescence microscope ,w hile neither lipid nanoparticles nor fluorescence were found in other sites of ventricular myocardium . Conclusions The viable myocardium can be targeted and acoustically enhanced by the self‐made nano‐scale ultrasound contrast agent . T his new agent has potential to improve sensitivity and specificity for noninvasive identifying viable myocardium .
ABSTRACT
Objective: To analyze contrast imaging characteristic and resistance to acoustic pressure of perfluorooctylbromide (PFOB) lipidic microbubbles and compared with perfluoropropane (C3F8) lipidic microbubbles in vitro. Methods: PFOB lipidic particles with biotin and C3F8 lipidic microbubbles with biotin were prepared, and the stability of them were evaluated. Then the agents were used for imaging before and after adding of avidin, and the signal intensity were compared. Both PFOB particles and C3F8 microbubbles were exposed in ultrasound field of low (MI=0.28) and high (MI=0.56) ultrasound pressure levels. Their signal intensity after different exposure time (10, 20, 30 s) were compared. Results: Aggregation occurred in both two contrast agents after addition of avidin,and the particle sizes were significantly larger before (both P<0.05). The differences of particle size between the two contrast agents were significant before (t=16.225, P<0.001) and after addition of avidin (t=-5.046,P<0.001). The concentration of PFOB lipid particles did not change significantly during the observation period of stability evaluation, while C3F8 microbubbles decreased with standing time. Addition of avidin produced significant imaging enhancement in PFOB particles. However, C3F8 microbubbles manifested ultrasonic backscatter before and after adding of avidin. The signal intensity of PFOB particles were stable under low (MI=0.28) and high acoustic pressure (MI=0.56). The signal intensity of C3F8 microbubbles decreased with the prolongation of exposure time under low (MI=0.28) and high acoustic pressure (MI=0.56). Conclusion: Compared with C3F8microbubbles, PFOB particles with smaller particle size and better resistance to acoustic pressure, more suitable for targeted contrast ultrasound imaging.
ABSTRACT
BACKGROUND: The aims of this study were to investigate the role of the Neurological Assessment of Neuro-Oncology (NANO) scale in predicting the prognosis of patients with glioblastoma, and compare these results to predicted data of the Karnofsky Performance Scale (KPS), and Eastern Cooperative Oncology Group (ECOG)/World Health Organization (WHO) performance status. Additionally, we examined other prognostic factors in glioblastoma patients. METHODS: The medical records of 76 patients with a new diagnosis of histologically ascertained glioblastoma in the period from January 2002 to December 2015 at the authors' institution were retrospectively reviewed. Clinical factors, including epidemiologic, radiologic, and therapeutic values were reviewed as well as the performance status assessed by the KPS, ECOG/WHO performance status, and NANO scale. RESULTS: The mean overall survival was 19.8 months (95% confidence interval 15.2–25.4 months). At initial diagnosis, the mean value [±standard deviation (SD)] of KPS score, ECOG/WHO performance status, and NANO scale were 81 (±7.4), 1.3 (±0.6), and 7.3 (±3.8), respectively. Multivariate analysis for predicting survival showed odds ratios of KPS score, ECOG/WHO performance status, and NANO scale were 2.502 (≥80 vs. < 80; p=0.024), 1.691 (0–1 vs. 2–5; p=0.047), and 2.763 (0–7 vs. 8–23; p=0.020), respectively. At the time of progression, the mean value (±SD) of KPS score, ECOG/WHO performance status, and NANO scale were 69 (±8.2), 1.6 (±0.7), and 11.4 (±4.2), respectively; multivariate analysis for predicting survival showed that the odd ratios for KPS score, ECOG/WHO performance status, and NANO scale were 2.007 (≥80 vs. < 80; p=0.035), 1.321 (0–1 vs. 2–5; p=0.143), and 3.182 (0–7 vs. 8–23; p=0.002), respectively. CONCLUSION: The NANO scale provided a more detailed and objective measure of neurologic function than that currently used for predicting the prognosis of glioblastoma patients, especially at the time of progression.
Subject(s)
Humans , Diagnosis , Glioblastoma , Medical Records , Multivariate Analysis , Odds Ratio , Prognosis , Retrospective StudiesABSTRACT
Objective To observe the morphology of ethanol-wet dentin surfaces and detect their nano-scale adhesion force (Fad) by atomic force microscopy (AFM) in order to explore the potential mechanism of ethanol-wet bonding in improving clinical dentin bonding effectiveness.Methods Dentin slices from human premolar roots were prepared into flat ones, polished, and then randomly divided into five groups.All the specimens were acid-etched, rinsed, and left moist.They were then treated with 100％ ethanol for 0s (control group), 20s, 60s, 3×60s, or stepwise ethanol application.Afterwards, each group was scanned for the morphology in air and the Fad was probed by AFM.One-way ANOVA followed by Tukey`s test was employed for multiple comparisons using SPSS16.0.Results Compared with control group, ethanol-wet dentine produced a less undulating and relatively smooth surface topography.Ethanol-wet protocol significantly decreased the value of Fad in the experimental groups (P0.05).Conclusion When using AFM in air, ethanol-wet protocol with longer time can produce a less undulating and relatively smooth surface topography and decrease the Fad, whichindicates that the water saturated in dentin matrix was replaced more thoroughly by longer ethanol application time.This will benefit hydrophobicity of the dentin bonding interface.
ABSTRACT
Objective To prepare a pancreatic cancer-targeted nano-scale ultrasound contrast agent (T-UCA) and to evaluate its in vitro targeting effect. Methods PLGA-PEG-NHS was synthesized with poly(lactic-co-glycolic acid) (PLGA) , N hydroxysuccinimide (NHS) and polyethylene glycol (PEG). The construction of PLGA-PEG-NHS was characterized by1H NMR. Perfluoroctyl bromide (PFOB) loaded PLGA nanoparticle contrast agent was prepared using emulsion evaporation technique with PLGA-PEG-NHS and PFOB , and the products were further conjugated with Hedgehog antibody. The morphology of T-UCA were characterized by transmission electron microscopy , and the size distribution and Zeta potential of T-UCA were characterized by dynamic light scattering method. Furthermore , the drug entrapment efficiency and loading capacity of T-UCA were determined by OC-MS , and the release rate of T-UCA in vitro was examined by dialysis method. Finally , the in vitro targeting performance was quantitatively verified by fluorescence microscopy and flow cytometry with human pancreatic cancer lines SW1990 and CFPAC-1. Results The average diameter and the Zeta potential of T-UCA were 198. 9 nm and -31. 8 mV, respectively. Moreover , the encapsulation efficiency and drug loading of T-UCA was (63. 7 ± 3. 9) % and (14.3 ± 0.9)% , respectively. Nearly 85. 3% liquid perfluorocarbon was released from the T-UCA within 48 h. In vitro cell experiments showed that the targeted contrast agent could bind to SW1990 cells which had high expression of Hedgehog antigen , while not to the CFPAC-1 cells without expression of Hedgehog antigen Conclusion The emulsion evaporation technique can be used to prepare T-UCA with desirable characteristics, and the prepared T-UCA can specifically cancer cells with high expression of Hedgehog, making it a promising pancreatic cancer-targeted nanosacle ultrasound contrast agent.
ABSTRACT
The objectives of this study was to determine whether a new physically modified cornstarch by ultra-fine- or nanoscale pulverizer to reduce particle size offers better bioactive function than native cornstarch in weanling Sprague-Dawley rats. Male weaning Sprague-Dawley rats were fed diets containing native cornstarch (NAC), ultra fine pulverized cornstarch (UFC) or nano-scale pulverized cornstarch (NSC) for 4 weeks. In vitro rate of starch hydrolysis, growth performance, organ weight, intestine length intestinal proliferation and the fermentation by Bifidobacterium of rat cecum were evaluated. The diet with reduced particle size (UFC or NSC) significantly increased body weight gain and organ weight. Feed efficiency was increased in NSC fed rats and was not affected in UFC fed rats. Intestinal proliferation was decreased in NSC group. Reduction of particle size also increased cecal short chain fatty acid concentration and the growth and acidifying activity of Bifidobacterium. It is concluded that a reduction of particle size of starch granules by physically modification may increase growing performance and gut function.