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Magnesium oxychloride cement (MOC) has been selected as a promising material for bone repair materials due to its prominent mechanical properties and non-toxicity towards mesenchymal stem cells. However, the limited water resistance of traditional MOC constrains its application range. Accordingly, this study investigated the impact of phytic acid (PA) on the mechanical properties, water resistance, and handling properties of MOC as a biomaterial, utilizing various macroscopic and microscopic characterization techniques. The results demonstrated that PA can enhance the mechanical strength and water resistance of MOC. Furthermore, multiple microscopic methods were employed to analyze the mechanism underlying the PA modification of MOC. These findings revealed that the insoluble gel-like structure was wrapped on the surface of the phase 5 crystals, which prevented the intrusion of water and improved the water resistance of MOC. Incorporating PA improved the injectability and degradability of MOC. Therefore, the development of this modified MOC provides a promising strategy for its application as a bone repair material. [ABSTRACT FROM AUTHOR]

A series of charge-switching amino acids-based cationic lipids 4a – 4e bearing a benzyl ester at the terminus of the acyl chain, but differing in the polar-head group were prepared. The physicochemical properties of these lipids, including size, zeta potential and cellular uptake of the lipoplexes formed from with DNA, as well as the transfection efficiency (TE), were investigated. The results showed that the chemical structure of the cationic head-group clearly affects the physicochemical parameters of the amino acid-based lipids and especially the TE. The selected lipid, 4c gave 2.1 times higher TE than bPEI 25k in the presence of 10% serum in HeLa cells, with little toxicity. [ABSTRACT FROM AUTHOR]

Abstract: Cationic lipids have become an efficient type of non-viral vectors for gene delivery. In this Letter, four cationic lipids containing 1,4,7-triazacyclononane (TACN) headgroup, glutamic/aspartic acid backbone and dioleyl tails were designed and synthesized. The TACN headgroup gives these lipids excellent pH buffering capacities, which were higher than branched 25kDa PEI. Cationic liposomes prepared from these lipids and DOPE showed good DNA affinity, and full DNA condensation was found at N/P ratio of 3 via agarose gel electrophoresis. The lipoplexes were characterized by dynamic light scattering (DLS) assay, which gave proper particle sizes and zeta-potentials for transfection. In vitro gene transfection results in two cell lines reveal that TAN (with aspartic acid and amide bond in the structure) shows the best transfection efficiency, which is close to commercially available transfection agent Lipofectamine 2000. [Copyright &y& Elsevier]

Abstract: A series of cyclen-based linear oligomers bearing hydrophobic long chains (lipopolymers Cy-LC, where Cy and LC represent cyclen-based linear backbone and hydrophobic long chain substituents, respectively) were designed and synthesized. The effects of type and degree of substitution (DS) of hydrophobic long chains on the transfection efficiency were systematically studied. The nitrogen atoms with relatively strong basicity on the cyclen ensure their good DNA binding ability, which was confirmed by gel retardation and ethidium bromide exclusion assays. Lipopolyplexes could be formed as nanoparticles with suitable sizes and zeta potentials for gene transfection. In vitro gene delivery experiments revealed that the linoleic acid (LIN) substituted material Cy-LIN has better transfection efficiency than 25kDa polyethylenimine in the absence or in the presence of serum. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and hemolysis assays showed low cytotoxicity and good biocompatibility of the lipopolyplexes. Fluorescent labeled DNA was used to study the cellular uptake and intracellular distribution of transfected DNA. Flow cytometry results suggested that a long chain is necessary for efficient cellular uptake, and images from confocal laser scanning microscopy showed that after 4h transfection, most of the fluorescent labeled DNA accumulated in the perinuclear region, which was required for efficient gene expression. Moreover, it was also found that the DS of the hydrophobic moiety can adjust the balance between DNA binding ability and dissociation of polyplexes, significantly affecting the transfection efficiency. [Copyright &y& Elsevier]

Abstract: For a clinically effective non-viral gene delivery system, a non-toxic and highly efficient vector is of great importance. A series of linear cationic polymers were synthesized by the ring-opening polymerization between diglycidyl ethers and diamines. Their structure–activity relationships as gene delivery vectors were systematically studied. Besides the amino groups with various densities, these polymers have uniform distribution of hydroxyl groups, which were formed in the polymerization and may benefit their biocompatibility and serum-tolerance. These polymers have good DNA binding ability and could condense DNA into nanoparticles with proper sizes and zeta-potentials. MTT assay revealed that polyplexes formed from title polymers have lower cytotoxicity than that derived from PEI. Most of the polymers have higher transfection efficiency than 25 kDa PEI in the in vitro transfection experiments. Polymers prepared from diglycidyl ethers with less or no N atom (2a and 2b) gave dramatically decreased TE, indicating that secondary amine on the backbone is highly required for efficient gene transfection, and compound 2 may be a good building block in the design of cationic polymers for gene delivery. More importantly, these polymers showed much better serum tolerance. Unlike PEI, the transfection mediated by P5 was seldom affected by the presence of 10% serum. Cellular uptake and intracellular distribution studies also confirmed the good performance of P5 in the transfection process with serum. [Copyright &y& Elsevier]

Lack of laboratory standards for cured tuberculosis (TB) can lead to early discharge of untreated TB patients from the hospital, resulting in increased risk of TB spread and of developing drug resistant Mycobacterium tuberculosis (Mtb). We used ultra-high performance liquid chromatography coupled with mass spectrometry (LC–MS) to detect heparin anticoagulant in plasma of untreated TB patients, two-month treated TB patients, cured TB subjects, and healthy controls. Screening of differentially expressed metabolites resulted in identification of four differentially expressed metabolites such as, l -Histidine, Arachidonic acid (AA), Biliverdin, and l -Cysteine-glutathione disulfide after 6 months of TB treatment. Among them, l -Cysteine-glutathione disulfide and AA could be identified after 2 months of TB treatment. We established a cured TB model with an area under the curve (AUC) of 0.909 (95% CI, 0.802–0.970), 86.2% sensitivity, and 85.2% specificity. The diagnostic model fitted from the four differential metabolites in combination (l -Histidine, AA, Biliverdin, and l -Cysteine-glutathione disulfide) can be used as potential biomarkers for cured TB. Our study provided laboratory standards for hospital discharge of TB patients, as well as experimental basis for evaluating the efficacy of anti-TB drugs. [ABSTRACT FROM AUTHOR]

A series of tocopherol-based cationic lipid 3a-3f bearing a pH-sensitive imidazole moiety in the dipeptide headgroup and a reduction-responsive disulfide linkage were designed and synthesized. Acid-base titration of these lipids showed good buffering capacities. The liposomes formed from 3 and co-lipid 1, 2-dioleoyl- sn -glycero-3-phosphocholine (DOPC) could efficiently bind and condense DNA into nanoparticles. Gel binding and HPLC assays confirmed the encapsulated DNA could release from lipoplexes 3 upon addition of 10 mM glutathione (GSH). MTT assays in HEK 293 cells demonstrated that lipoplexes 3 had low cytotoxicity. The in vitro gene transfection studies showed cationic dipeptide headgroups clearly affected the transfection efficiency (TE), and arginine-histidine based dipeptide lipid 3f give the best TE, which was 30.4 times higher than Lipofectamine 3000 in the presence of 10% serum. Cell-uptake assays indicated that basic amino acid containing dipeptide cationic lipids exhibited more efficient cell uptake than serine and aromatic amino acids based dipeptide lipids. Confocal laser scanning microscopy (CLSM) studies corroborated that 3 could efficiently deliver and release DNA into the nuclei of HeLa cells. These results suggest that tocopherol-based dipeptide cationic lipids with pH and reduction dual-sensitive characteristics might be promising non-viral gene delivery vectors. [ABSTRACT FROM AUTHOR]

A series of reducible cationic lipids 4a – 4f with different amino acid polar-head groups were prepared. The novel lipid contains a hydrophobic lipoic acid (LA) moiety, which can be reduced under reductive conditions to release of the encapsulated plasmid DNA. The particle size, zeta potential and cellular uptake of lipoplexes formed with DNA, as well as the transfection efficacy (TE) were characterized. The TE of the cationic lipid based on arginine was especially high, and was 2.5 times higher than that of a branched polyethylenimine in the presence of 10% serum. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bioinspired HMVs were prepared by fusing erythrocyte membranes with MSC membranes, which could enhance renal homing abilities and prolong blood circulation time in vivo. • SAB@HMVs stagnated the mesangial support area in the GN model, augmenting the renal delivery of SAB, and eliciting an effective anti-inflammatory response to improve the pathological changes in the glomerular mesangial region. • The anti-inflammatory mechanism of SAB@HMVs should be based on regulating MAPK and NF-κB signaling pathways. • Biomimetic hybrid membranes loaded with pure drugs such as the hybrid nanovesicle HMVs not only act as a potential strategy for inflammatory therapy but also provide an address to multiple clinical needs and a promising platform for other biomedical applications via rational design. Mesangial cell (MC)-mediated immune inflammatory injury is a basic pathological process in glomerulonephritis. However, due to the limited drug accumulation and serious adverse effects, it remains challenging to explore a rational delivery system integrating high efficiency and low toxicity to deliver anti-inflammatory drugs to the glomerular MC region. Salvianolic acid B (SAB)-loaded hybrid membrane biomimetic nanovesicles (SAB@HMVs) were developed by fusing erythrocyte membrane nanovesicles with mesenchymal stem cells biomimetic membrane nanovesicles. SAB@HMVs had a spheroidal structure, low cytotoxicity, particle size of 143.83 ± 1.33 nm and exhibited a high drug loading capacity (7.02 %±0.30 %) along with a good sustained release function. The in vitro anti-inflammatory results revealed that HMVs were effectively taken up by MCs and showed significant anti-inflammatory activity. Furthermore, in vivo pharmacodynamic studies revealed that SAB@HMVs could deliver SAB to kidney tissue and elicit an effective anti-inflammatory response to improve the pathological changes in the glomerular mesangial region, significantly reducing the levels of cytokines and alleviating kidney inflammation. Especially, noteworthy was the observation that SAB@HMVs augmented the renal delivery of SAB, downregulated the gene expression of p38 MAPK and NF-κB, inhibited the levels of MMP9 and TNF-α proteins as well as elevated the level of iκB protein, indicating that the anti-inflammatory mechanism of SAB@HMVs should be based on regulating MAPK and NF-κB signaling pathways. We provided a novel strategy to increase nanovesicles accumulation in MCs with the potential to exert anti-inflammatory regulatory effects in glomerulonephritis. Furthermore, this biomimetic hybrid membrane loaded with pure drugs may offer a functional platform to address multiple clinical needs. [ABSTRACT FROM AUTHOR]

Abstract: A series of novel 1,4,7,10-tetraazacyclododecanes (cyclen)-based cationic lipids bearing histidine imidazole group 10a–10e were synthesized. These amphiphilic molecules have different hydrophobic tails (long chain, cholesterol or α-tocopherol) and various type of linking groups (ether, carbamate or ester). These molecules were used as non-viral gene delivery vectors, and their structure–activity relationships were investigated. As expected, the imidazole group could largely improve the buffering capabilities comparing to cyclen. The liposomes formed from 10 and dioleoylphosphatidyl ethanolamine (DOPE) could bind and condense plasmid DNA into nanoparticles with proper size and zeta-potentials. Comparing with Lipofectamine 2000, the formed lipoplexes gave lower transfected cells proportion, but higher fluorescence intensity, indicating their good intracellular delivering ability. Furthermore, results indicate that transfection efficiency of the cationic lipids is influenced by not only the hydrophobic tails but also the linking group. The cyclen-based cationic lipid with α-tocopherol hydrophobic tail and an ester linkage could give the highest transfection efficiency in the presence of serum. [Copyright &y& Elsevier]

Abstract: A series of novel cationic lipids based on 1,4,7-triazacyclononane (TACN) with different hydrophobic chains were synthesized via the formation of a biodegradable ester bond. These lipids were found to have good buffering capacity at the pH range of 5.0–6.5, which is similar to that of the acidic endosomal compartments. The liposomes formed from these lipids and DOPE could condense DNA into nanoparticles with proper sizes. In vitro experiments showed moderate to good gene transfection efficiency of the formed lipoplexes. The structure–activity relationships of this type of lipids were discussed. [Copyright &y& Elsevier]

• This study is the first to screen the potential lncRNA biomarkers for cured tuberculosis (TB) in human plasma. • Two lncRNAs were identified as potential novel biomarkers for cured TB. • A cured TB model was established with an AUC (area under the curve) of 0.945. • Three target genes of the two lncRNAs were predicted. • The new strategy provided in this study is different from the existing bacterial tests. Tuberculosis (TB) treatment takes a long time, and a gold standard test to define TB cure is lacking. This may lead to early discharge of TB patients, resulting in an increased risk of disease transmission and drug resistance. Plasma lncRNAs might act as potential biomarkers to evaluate TB cure in an efficient and precise manner. A lncRNA microarray assay was used to screen differentially expressed plasma lncRNAs in untreated TB and cured TB subjects. The expression levels of lncRNAs were verified by qPCR. Target genes of lncRNAs were predicted using a coding–non-coding gene co-expression network and mRNA–lncRNA–miRNA interaction network analysis. The expression levels of lncRNAs uc.48+ (p < 0.001) and NR_105053 (p = 0.03) were found to differ significantly between the untreated TB group and the cured TB group. The predicted target genes of uc.48+ were EP300, BAI1 and NR_105053 were TLR9, MYD88, BAI1, respectively. A predictive model for cured TB was established by the combination of uc.48+ and NR_105053 expression, with a sensitivity of 90.00% and specificity of 86.36%, and an area under the curve (AUC) value of 0.945. lncRNAs uc.48+ and NR_105053 may serve as potential biomarkers to distinguish between untreated TB patients and cured TB subjects. This study provides an experimental basis to evaluate the effect of TB treatment and may also provide new clues to the pathological mechanisms of TB. [ABSTRACT FROM AUTHOR]