Controllable Self-Assembly of Amphiphilic Dendrimers on a Silica Surface: The Effect of Molecular Topological Structure and Salinity

The adsorption kinetics and equilibrium of amphiphilic dendrimers based on poly­(amidoamine) modified with a dodecyl chain, G<i>_n</i>QPAMC₁₂ (<i>n</i> represents the generation number), with different generation numbers at a silica–water interface have been investigated. The effect of molecular shape with different charge characteristics on the adsorption kinetics, adsorption isotherms, and the conformation of a self-assembled layer has been elucidated. For the adsorption kinetics, two steps were observed including the adsorption of individual molecules at concentrations below the critical micelle concentration (cmc) and the predominant adsorption of aggregates above the cmc. However, the adsorption isotherm, as a function of the generation number, presented an exceptional characteristic, in which a decrease in adsorption mass with different levels occurred in a high generation of amphiphilic dendrimers, depending on the balance of hydrophobic interaction and electrostatic repulsion. Atomic force microscopy imaging showed that flattened films with pores (spacing) of various shapes and roughness of 3–4 nm were formed, of which the pores (spacing) decreased obviously as the generation number increased. The addition of electrolyte (NaBr) has a great effect on the film morphology formed by the G₃QPAMC₁₂ dendrimer adsorbed at the silica–water interface, showing that the film became closer with smaller pores with increased NaBr concentration

Univariate analysis of progression-free survival and overall survival in 176 patients with advanced lung adenocarcinoma.

<p>Univariate analysis of progression-free survival and overall survival in 176 patients with advanced lung adenocarcinoma.</p

Univariate analysis of progression-free survival and overall survival in patients with the EGFR mutation.

<p>Univariate analysis of progression-free survival and overall survival in patients with the EGFR mutation.</p

Kaplan–Meier survival analysis.

<p><b>a</b> progression-free survival (PFS) and <b>b</b> overall survival (OS) according to whole-body total lesion glycolysis (TLG_WBR) determined using the Response Evaluation Criteria In Solid Tumors 1.1 criteria in 176 patients with advanced lung adenocarcinoma. Kaplan–Meier analysis of <b>c</b> PFS and <b>d</b> OS according to TLG_WBR in 85 patients with wild-type EGFR. <b>e</b> Kaplan–Meier analysis of PFS and <b>f</b> OS according to TLG_WBR in 91 patients with the EGFR mutation.</p

Table_1_Planting grass enhances relations between soil microbes and enzyme activities and restores soil functions in a degraded grassland.DOCX

IntroductionForage culture is a common way to restore degraded grasslands and soil functions, in which the reconstruction of the soil microbial community and its relationship with extracellular enzyme activity (EEAs) can characterize the recovery effects of degraded grasslands. However, the impacts of forage culture on the interaction between soil microbes and EEAs and whether the recovery effect of soil functions depends on the varying degradation statuses remain unclear.MethodsWe conducted a plantation of a dominant grass, Leymus chinensis, in the soil collected from severe, moderate, light, and non-degradation statuses in the Songnen grassland in northeastern China. We measured soil microbial diversity and soil EEAs, and predicted microbial functional groups using FUNGuild.ResultsThe results showed that L. chinensis culture promoted soil bacterial alpha diversity and soil EEAs only in the moderate degradation status, indicating a dramatic dependence of the recovery effects of the grass culture on degradation status of the grassland. After planting L. chinensis for 10 weeks, a decreasing trend in the chemoheterotrophy and nitrate-reduction microbial functional groups was found. In contrast, the abundance of the nitrogen (N)-fixing microbial functional group tended to increase. The positive correlation between soil EEAs and the nitrate-reduction and N-fixing microbial functional groups was enhanced by planting L. chinensis, indicating that grass culture could promote soil N cycle functions.ConclusionWe illuminate that grass culture may promote the restoration of soil functions, especially soil N cycling in degraded grasslands, and the recovery effect may depend on the grassland degradation status. We emphasized that selection of the plant species for restoration of grasslands needs to consider the restoration effects of microbial functional groups and soil functions.</p

Univariate analysis of progression-free survival and overall survival in patients with wild-type EGFR.

<p>Univariate analysis of progression-free survival and overall survival in patients with wild-type EGFR.</p

miR-27a protects human mitral valve interstitial cell from TNF-α-induced inflammatory injury via up-regulation of NELL-1

<div><p>MicroRNAs (miRNAs) have been reported to be associated with heart valve disease, which can be caused by inflammation. This study aimed to investigate the functional impacts of miR-27a on TNF-α-induced inflammatory injury in human mitral valve interstitial cells (hMVICs). hMVICs were subjected to 40 ng/mL TNF-α for 48 h, before which the expressions of miR-27a and NELL-1 in hMVICs were altered by stable transfection. Trypan blue staining, BrdU incorporation assay, flow cytometry detection, ELISA, and western blot assay were performed to detect cell proliferation, apoptosis, and the release of proinflammatory cytokines. We found that miR-27a was lowly expressed in response to TNF-α exposure in hMVICs. Overexpression of miR-27a rescued hMVICs from TNF-α-induced inflammatory injury, as cell viability and BrdU incorporation were increased, apoptotic cell rate was decreased, Bcl-2 was up-regulated, Bax and cleaved caspase-3/9 were down-regulated, and the release of IL-1β, IL-6, and MMP-9 were reduced. NELL-1 was positively regulated by miR-27a, and NELL-1 up-regulation exhibited protective functions during TNF-α-induced cell damage. Furthermore, miR-27a blocked JNK and Wnt/β-catenin signaling pathways, and the blockage was abolished when NELL-1 was silenced. This study demonstrated that miR-27a overexpression protected hMVICs from TNF-α-induced cell damage, which might be via up-regulation of NELL-1 and thus modulation of JNK and Wnt/β-catenin signaling pathways.</p></div

Self-Aggregation of Amphiphilic Dendrimer in Aqueous Solution: The Effect of Headgroup and Hydrocarbon Chain Length

The self-aggregation of amphiphilic dendrimers G₁QPAMC_<i>m</i> based on poly­(amidoamine) PAMAM possessing the same hydrophilic group but differing in alkyl chain length in aqueous solution was investigated. Differences in the chemical structures lead to significant specificities in the aggregate building process. A variety of physicochemical parameters presented monotonous regularity with the increase in alkyl chain length in multibranched structure, as traditional amphiphilic molecules. A significant difference, however, existed in the morphology and the microenvironment of the microdomain of the aggregates, with G₁QPAMC_<i>m</i> with an alkyl chain length of 16 intending to form vesicles. To obtain supporting information about the aggregation mechanism, the thermodynamic parameters of micellization, the free Gibbs energy Δ<i>G</i>_mic, and the entropy Δ<i>S</i>_mic were derived subsequently, of which the relationship between the hydrophobic chain length and the thermodynamic properties indicated that the self-assembly process was jointly driven by enthalpy and entropy. Other than traditional surfactants, the contribution of enthalpy has not increased identically to the increase in hydrophobic interactions, which depends on the ratio of the alkyl chain length to the radius in the headgroup. Continuous increases in the hydrophobic chain length from 12 to 16 lead to the intracohesion of the alkyl chain involved in the process of self-assembly, weakening the hydrophobic interactions, and the increase in −Δ<i>H</i>_mic, which offers an explanation of the formation of vesicular structures

Subnanogram Mass Measurements on Plasmonic Nanoparticles for Temperature-Programmed Thermal Analysis

Ultrasensitive thermogravimetric analysis of adsorbed organic molecules has been achieved on an ordered array of gold nanoparticles used as a novel plasmonic nanobalance. The extinction peaks of the resonating surface plasmon of nanoparticle arrays shift upon loading molecules and return to the original position after a linear temperature rise process. A good correlation exists between the film thickness and magnitude of peak shifts. The detection range of plasmonic nanobalance derived from our results can reach a subnanogram level (1.8 pg on an active area of 100 μm²), which is much lower than those of mechanical or electronic mass-measuring devices. Such high mass sensitivity, combined with the remote detection capability and high-temperature operation of plasmonic sensors, allows the in situ detections of the masses of loaded material and thermally desorbed molecules

Table_1_Bovine milk with variant β-casein types on immunological mediated intestinal changes and gut health of mice.DOCX

Dietary proteins provide bioactive peptides, which are important for host gastrointestinal functions. We hypothesized that A2-type β-casein could provide gastrointestinal benefits and improve the immune and gut health. This study was conducted to investigate those effects and mechanisms. Thirty BALB-c mice (3–4 weeks old) were fed with either a control diet (control), a diet supplemented with bovine milk containing A1 and A2 type β-casein (A1A2, contains 63.62% A2 β-casein of total β-casein) or a diet containing A2 type β-casein (A2A2, contains 95.96% A2 β-casein of total β-casein) (10 ml/kg body weight) for 4 weeks. Immunoglobulin and inflammation factors were measured in serum, and histological variations were measured in duodenal and ileum, and stool 16S rRNA and short-chain fatty acids (SCFAs) contents were measured in fecal samples. Results showed that consumption of A2-type β-casein milk could improve proximal small intestine villus and crypt morphology (p < 0.05), increase IgG and IgE responses, and modulate the composition and diversity of gut microbiota by increase the relative abundance of phylum Proteobacteria, class Clostridia, family Ruminococcaceae and species Lactobacillus animalis (p < 0.05). There were also significant associations between gut microbes, immune response, and SCFAs, especially isobutyric acid (p < 0.05), which may potentially regulated gastrointestinal benefits. Moreover, intake of A2-type β-casein milk had no impact on inflammation. These findings explained potential benefits of consumption of A2-type β-casein milk on host immune system and gut health outcomes, and provide insights to the future application of nutritional modulation.</p