Association Between Serum C1q Tumor Necrosis Factor-Related Protein 9 and the Clinical Characteristics and Prognosis of Ischemic Stroke.

INTRODUCTION: C1q tumor necrosis factor (TNF)-related protein 9 (CTRP9) is a novel member of the C1q/TNF superfamily. According to our previous review, CTRP9 plays a vital role in the process of cardiovascular diseases, including regulating energy metabolism, modulating vasomotion, protecting endothelial cells, inhibiting platelet activation, inhibiting pathological vascular remodeling, stabilizing atherosclerotic plaques, and protecting the heart. We proposed that CTRP9 could play multiple positive and beneficial roles in vascular lesions in ischemic stroke (IS). Here, we aimed to study the relationship between serum CTRP9 and the etiology, severity, and prognosis of IS patients. METHODS: A total of 302 patients with IS and 173 non-stroke controls were selected from the same hospital, and all patients with IS were followed up 12 months after stroke onset. Stroke etiology was classified according to the Trial of ORG 10172 in Acute Stroke Treatment classification. Symptomatic severity was determined using the National Institutes of Health Stroke Scale score. The lesion volume of acute cerebral ischemia was measured using magnetic resonance imaging (MRI). The unfavorable functional outcome was a combination of death or major disability 12 months after stroke onset. Receiver operating characteristic (ROC) curves and integrated discrimination improvement (IDI) and net reclassification improvement (NRI) statistics were applied in the statistical analysis. RESULTS: We found that serum CTRP9 levels and the ratios of CTRP9/total cholesterol (TC), CTRP9/triglyceride (TG), CTRP9/low-density lipoprotein cholesterol (LDL-C), and CTRP9/high-density lipoprotein cholesterol (HDL-C) were associated with the presence of IS. Moreover, the serum CTRP9 concentration was positively associated with the severity of IS. Incorporation of CTRP9/LDL-C levels into a fully adjusted model for IS-cardioembolic (CE) improved discrimination and calibration, and significantly improved reclassification. In addition, CTRP9 was a predictor of unfavorable functional outcomes. CONCLUSIONS: All the findings indicated that serum CTRP9 could be a promising blood-derived biomarker for the early evaluation and prognosis assessment of IS. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1800020330.

Parabiosis modeling: protocol, application and perspectives.

Parabiosis is a surgical method of animal modeling with a long history. It has been widely used in medical research, particularly in the fields of aging, stem cells, neuroscience, and immunity in the past two decades. The protocols for parabiosis have been improved many times and are now widely accepted. However, researchers need to consider many details, from surgical operation to perioperative management, to reduce mortality and maintain the parabiosis union. Although parabiosis has certain inevitable limitations, it still has broad application prospects as an irreplaceable animal model in the medical research field.

Two-component reduction-sensitive lipid-polymer hybrid nanoparticles for triggered drug release and enhanced in vitro and in vivo anti-tumor efficacy.

An amphiphilic polymer DLPE-S-S-MPEG was synthesized and employed with PCL to prepare two-component reduction-sensitive lipid-polymer hybrid nanoparticles (SLPNPs) for in vitro and in vivo delivery of a hydrophobic anticancer drug (Doxorubicin, DOX). Insensitive lipid-polymer hybrid nanoparticles (ILPNPs) were prepared as a control. The mean sizes of the LPNPs ranged from 100 nm to 120 nm. The TEM observations showed that the LPNPs have spherical morphologies with homogeneous distribution. The disulfide bond of DLPE-S-S-MPEG was cleaved by dithiothreitol (DTT), which resulted in the disassembly of SLPNPs and triggered the release of encapsulated DOX. The in vitro cytotoxicities of DOX/LPNPs against HeLa cells, HepG2 cells and COS-7 cells were studied. It was demonstrated that DOX/SLPNPs showed higher cytotoxicity against HeLa cells and HepG2 cells than DOX/ILPNPs, but showed a slight difference in the case of COS-7 cells. CLSM observation and FCM measurement further confirmed that the introduction of S-S bonds caused fast intracellular release of DOX from SLPNPs. Moreover, compared with DOX/ILPNPs and free DOX, DOX/SLPNPs exhibited higher antitumor activity. Both DOX/SLPNPs and DOX/ILPNPs showed lower cardiac toxicity and kidney toxicity than free DOX, which were confirmed by histological and immunohistochemical analyses. The tissue distribution of DOX in mice exhibited that two kinds of DOX/LPNPs accumulated extensively in the liver and spleen, while free DOX accumulated mainly in the heart and kidney 12 h after injection. Two-component SLPNPs may be a promising drug delivery carrier for reduction-triggered delivery of DOX.

Plant Clonal Integration Mediates the Horizontal Redistribution of Soil Resources, Benefiting Neighboring Plants.

Resources such as water taken up by plants can be released into soils through hydraulic redistribution and can also be translocated by clonal integration within a plant clonal network. We hypothesized that the resources from one (donor) microsite could be translocated within a clonal network, released into different (recipient) microsites and subsequently used by neighbor plants in the recipient microsite. To test these hypotheses, we conducted two experiments in which connected and disconnected ramet pairs of Potentilla anserina were grown under both homogeneous and heterogeneous water regimes, with seedlings of Artemisia ordosica as neighbors. The isotopes [(15)N] and deuterium were used to trace the translocation of nitrogen and water, respectively, within the clonal network. The water and nitrogen taken up by P. anserina ramets in the donor microsite were translocated into the connected ramets in the recipient microsites. Most notably, portions of the translocated water and nitrogen were released into the recipient microsite and were used by the neighboring A. ordosica, which increased growth of the neighboring A. ordosica significantly. Therefore, our hypotheses were supported, and plant clonal integration mediated the horizontal hydraulic redistribution of resources, thus benefiting neighboring plants. Such a plant clonal integration-mediated resource redistribution in horizontal space may have substantial effects on the interspecific relations and composition of the community and consequently on ecosystem processes.

[C21 steroids from the stems of Marsdenia tenacissima].

To study the C21 steroids of the stems of Marsdenia tenacissima (Roxb.) Wight et Arn, various chromatography methods were used for the isolation of the constituents and their structures were identified by spectral analysis. Eight C21 steroids were isolated from the CHCl3 extract, which were identified as 11alpha-O-tigloyl-17beta-tenacigenin B (1), 17beta-tenacigenin B (2), tenacigenoside A (3), 11alpha-O-2-methylbutyryl-12beta-O-acetyl tenacigenin B (4), tenacissoside H (5), marsdenoside A (6), tenacissoside G (7), and tenacissoside I (8). Among them, compound 1 is a new compound.

Galactosylated ternary DNA/polyphosphoramidate nanoparticles mediate high gene transfection efficiency in hepatocytes.

Galactosylated polyphosphoramidates (Gal-PPAs) with different ligand substitution degrees (6.5%, 12.5% and 21.8%, respectively) were synthesized and evaluated as hepatocyte-targeted gene carriers. The in vitro cytotoxicity of Gal-PPA decreased significantly with an increase in galactose substitution degree. The affinity of Gal-PPA/DNA nanoparticles to galactose-recognizing lectin increased with galactose substitution degree. However, decreased transfection efficiency was observed for these galactosylated PPAs in HepG2 cells. Based on the results of gel retardation and polyanion competition assays, we hypothesized that the reduced transfection efficiency of Gal-PPA/DNA nanoparticles was due to their decreased DNA-binding capacity and decreased particle stability. We therefore prepared nanoparticles by precondensing DNA with PPA at a charge ratio of 0.5, yielding nanoparticles with negative surface charge, followed by coating with Gal-PPA, resulting in a Gal-PPA/ DNA/PPA ternary complex. Such a ternary nanoparticle formulation led to significant size reduction in comparison with binary nanoparticles, particularly at low N/P ratios (2 to 5). In HepG2 cells and primary rat hepatocytes, and at low N/P ratios (2 to 5), transfection efficiency mediated by ternary nanoparticles prepared with 6.5% Gal-PPA was 6-7200 times higher than PPA-DPA/DNA nanoparticles. Transgene expression increased slightly at higher N/P ratios in HepG2 cells and reached a plateau at N/P ratios between 5 and 10 for primary rat hepatocytes. Such an enhancement effect was not observed in HeLa cells that lack of asialoglycoprotein receptor (ASGPR). Nevertheless, transfection efficiency of ternary particles decreased dramatically, presumably due to the decreased DNA binding capacity and particle stability, as PPA galactosylation degree increased. This highlights the importance of optimizing ligand conjugation degree for PPA gene carrier.

In vitro gene delivery using polyamidoamine dendrimers with a trimesyl core.

Polyamidoamine (PAMAM) dendrimer represents one of the most efficient polymeric gene carriers. To investigate the effect of the core structure and generation of dendrimers on the complex formation and transfection efficiency, a series of PAMAM dendrimers with a trimesyl core (DT) at different generations (DT4 to DT8) were developed as gene carriers and compared with the PAMAM dendrimers derived from pentaerythritol (DP) and inositol (DI). The minimal generation number of DTs at which the dendrimer has enough amino group density to effectively condense DNA was higher (generation 6) than those of DPs and DIs (generation 5). DTs of generation 6 or higher condensed DNA into complexes with an average diameter ranging from 100 to 300 nm, but the 4th and 5th generations of DT (DT4 and DT5) formed only a severe aggregate with DNA. Interestingly, the DT6/pDNA complex was determined to be much smaller (100-300 nm) than those prepared with DP5 or DI5 (>600 nm) at N/P ratios higher than 15. The optimal generation numbers at which the dendrimers showed the highest transgene expression in COS-7 cells were 5 for DPs and DIs but 6 for DTs. The DT6/pDNAcomplex with smaller size mediated higher transgene expression in COS-7 cells than those prepared with DP5 or DI5. The in vitro transfection efficiency of the DT dendrimers as evaluated in HeLa cells, COS-7 cells, and primary hepatocytes decreased in the order of DT6 > DT7 > DT8 > DT5 > DT4. The transfection mediated by DT6 was significantly inhibited by bafilomycin A1. The acid-base titration curve for DT6 showed high buffer capacity in the pH range from 5.5 to 6.4 (pK(a) approximately 6). This permits dendrimers to buffer the pH change in the endosomal compartment. However, the transfection efficiency mediated by DT6 decreased significantly in the presence of serum in both HeLa cells and COS-7 cells. The cytotoxicity of DTs evaluated in HeLa cells using the 3-{4,5-dimethylthiazol-2-yl}-2,5-diphenyltetrazolium bromide assay showed a trend of increasing toxicity with the polymer generations. The LD50 values of DT4 through DT8 were 628, 236, 79, 82, and 77 microg/mL, respectively, which were higher than that of poly(ethyleneimide) (18 microg/mL) and poly(L-lysine) (28 microg/mL) in the same assay. With a lower cytotoxicity and versatility for chemical conjugation, these PAMAM dendrimers with a DT core warrant further investigation for nonviral gene delivery.