Liquid Crystalline Nanoparticles via Polymerization-Induced Self-Assembly: Morphology Evolution and Function Regulation.

Liquid crystalline nanoparticles (LC NPs) are a kind of polymer NPs with LC mesogens, which can form special anisotropic morphologies due to the influence of LC ordering. Owing to the stimuli-responsiveness of the LC blocks, LC NPs show abundant morphology evolution behaviors in response to external regulation. LC NPs have great application potential in nano-devices, drug delivery, special fibers and other fields. Polymerization-induced self-assembly (PISA) method can synthesize LC NPs at high solid content, reducing the harsh demand for reaction solvent of the LC polymers, being a better choice for large-scale production. In this review, we introduced recent research progress of PISA-LC NPs by dividing them into several parts according to the LC mesogen, and discussed the improvement of experimental conditions and the potential application of these polymers.

Prevalence and Genetic Analysis of ß-Thalassemia in the Dali Bai Autonomous Prefecture of the Yunnan Province, China.

Background: ß-Thalassemia is the most common monogenetic hemolytic hemoglobin-associated disease in the south of China; the distribution of genetic mutations associated with this condition varies according to geographic regions. This study investigated the prevalence and distribution of ß-thalassemia-associated mutations across different ethnic groups in the Dali Bai Autonomous Prefecture of the Yunnan Province, China. Methods: This cross-sectional study included 4723 participants (15-45 years old) who volunteered for thalassaemia screening from the Dali Bai Autonomous Prefecture from May 2017 to October 2020. Cellulose acetate membrane electrophoresis was used to screen for ß-thalassemia carriers. Genotypic analyses was performed using polymerase chain reaction-based reverse dot blotting and DNA sequencing. Results: The overall prevalence of ß-thalassemia in the study population was 2.01%. The genotypic analyses showed the presence of four types of mutations in the ß-globin gene: CD26 (GAG→AAG), CD56 (GGC→GAC), IVS-II-81 (C→T), and CD121 (GAA→CAA). In contrast to previous studies from other regions of Yunnan Province, our results showed that the prevalence of CD26 mutations was significantly higher than that of the other mutations. Conclusion: Our data suggests that the Dali Autonomous Prefecture is an area with a high prevalence of ß-thalassemia. Moreover, CD26 was the only ß-thalassemia mutation that we have detected. Moreover, the vast majority of the ß-thalassemia mutations observed were CD26.

Synthesis of Starch-Based Amphiphilic Fluorescent Nanoparticles and Their Application in Biological Imaging.

Due to the extensive source, good biocompatibility and biodegradability, the starch of carbohydrates has been extensively investigated for application in biological field. Recently, the development of fluorescent organic nanoparticles (FONs) on the basis of aggregation induced emission (AIE) dyes has attracted great research interest. In this article, novel starch-based S-TPEV polymers with AIE property were successfully fabricated by atom transfer radical polymerization (ATRP) of TPEV dye into water-soluble starch for the first time, subsequently, their structure and properties were detailedly investigated by 1H NMR, TEM, UV-vis, FL and FTIR. The characterization results confirmed the successful synthesis of S-TPEV polymers, and the molar fraction of TPEV and C6H10O5 ring in the starch polymers could be respectively calculated as approximate 5.8% and 94.2%. In aqueous solution, the as-prepared S-TPEV polymers will tend to self-assemble into FONs with 100-200 nm diameters, and their fluorescence intensity increased with the increase of the concentration of water in the mixed solution of water and DMSO, indicative of the obvious AIE property. More importantly, owing to their high water dispersity, good fluorescence and excellent biocompatibility, the S-TPEV FONs can be uptaken by HepG2 cells and show promising application in biological imaging field.

Facile and efficient fabrication of photoresponsive microgels via thiol-Michael addition.

A photoresponsive microgel is designed by the combination of a noncovalent assembly strategy with a covalent cross-linking method. End-functionalized poly(ethylene glycol) with azobenzene [(PEG-(Azo)(2))] was mixed with acrylate-modified ß-CD (ß-CD-MAA) to form photoresponsive inclusion complex through host-guest interaction. The above photoresponsive complex was cross-linked by thiol-functionalized PEG (PEG-dithiol) via Michael addition click reaction. The photoreversibility of resulted microgel was studied by TEM, UV-Vis spectroscopy, and (1)H NMR measurements. The characterization results indicated that the reversible size changes of the microgel could be achieved by alternative UV-Vis irradiations with good repeatability.

Multivariate variance-components analysis of longitudinal blood pressure measurements from the Framingham Heart Study.

Multivariate variance-components analysis provides several advantages over univariate analysis when studying correlated traits. It can test for pleiotropy or (in the longitudinal context) gene x age interaction. It can also have more power than univariate analyses to detect a quantitative trait locus influencing several traits. We apply multivariate variance components to longitudinal systolic blood pressure data from the Framingham Heart Study. We find evidence for a polygenic influence on blood pressure (heritabilities at different ages range from 27% to 38%). Tests based on a factor-analytic parameterization of the polygenic variance find significant (p < 2 x 10(-3)) evidence that different genes affect blood pressure at different ages. Still, estimates for the proportion of polygenic variance due to shared genes ran as high as 85% for some trait pairs. Univariate and multivariate linkage analyses replicate previous linkage results on chromosome 17 (maximum LOD scores of 2.2 and 2.4, respectively). In this study, multivariate analysis provides no increase in power; this is likely due to the strong positive correlation in systolic blood pressure measured at different ages.