Novel complex disease allele mutations in cleidocranial dysplasia patients.

This study reports a novel identical complex disease allele harboring two non-synonymous mutations that were identified in two southern Chinese individuals of the same family with cleidocranial dysplasia (CCD). Blood samples were obtained from the proband, his parents, plus 100 matched control subjects. Exons 0 to 7 of the RUNX2 gene were amplified using specific primers and sequenced. Multiple sequence alignment and protein structure modeling was performed using ClustalW2 and MODBASE software while PolyPhen-2 and MutationTaster applications were employed to predict the disease-causing potential of the identified mutations. A complex disease allele in two affected individuals harboring two non-synonymous mutations in a cis-position on exons 4 (D273N) and 5 (P299L) were identified. The identified mutations were in the conserved region and changed the protein structure.

Protection of nonself surfaces from complement attack by factor H-binding peptides: implications for therapeutic medicine.

Exposure of nonself surfaces such as those of biomaterials or transplanted cells and organs to host blood frequently triggers innate immune responses, thereby affecting both their functionality and tolerability. Activation of the alternative pathway of complement plays a decisive role in this unfavorable reaction. Whereas previous studies demonstrated that immobilization of physiological regulators of complement activation (RCA) can attenuate this foreign body-induced activation, simple and efficient approaches for coating artificial surfaces with intact RCA are still missing. The conjugation of small molecular entities that capture RCA with high affinity is an intriguing alternative, as this creates a surface with autoregulatory activity upon exposure to blood. We therefore screened two variable cysteine-constrained phage-displayed peptide libraries for factor H-binding peptides. We discovered three peptide classes that differed with respect to their main target binding areas. Peptides binding to the broad middle region of factor H (domains 5-18) were of particular interest, as they do not interfere with either regulatory or binding activities. One peptide in this group (5C6) was further characterized and showed high factor H-capturing activity while retaining its functional integrity. Most importantly, when 5C6 was coated to a model polystyrene surface and exposed to human lepirudin-anticoagulated plasma, the bound peptide captured factor H and substantially inhibited complement activation by the alternative pathway. Our study therefore provides a promising and novel approach to produce therapeutic materials with enhanced biocompatibility.

The clinical significance comparison of a latex agglutination based syphilis screening test at low antibody titer.

The rapid increase of syphilis underscores a tremendous need to carefully evaluate many new serological tests for syphilis and choose efficient and economical strategies for syphilis screening, especially in the case of primary infection with low antibody titer. Between 2011 and 2012, 73 patients' sera samples were included in this retrospective study. They were either TRUST or TPPA reactive, either LA (latex agglutination) based auto3 TP or CLIA (chemiluminescence assay) based Architect Syphilis TP assay reactive. The contradictory weak response samples were further examined by FTA-Abs method. TPPA could not give reactive results in samples with antibody concentration less than 10 mIU. Auto3 TP reagent shows good linearity at low antibody titers and was more sensitive than TPPA, while the former does not show significant superiority compared to the Architect Syphilis TP assay at low antibody titer, except that it is suitable for adaptation on diverse automated chemistry analyzers.

Synthesis and physicochemical characterization of amphiphilic triblock copolymer brush containing pH-sensitive linkage for oral drug delivery.

A novel and well-defined pH-sensitive amphiphilic triblock copolymer brush poly(lactide)-b-poly(methacrylic acid)-b-poly(poly(ethylene glycol) methyl ether monomethacrylate) (PLA-b-PMAA-b-PPEGMA) and its self-assembled micelles were developed for oral administration of hydrophobic drugs. The copolymer and its precursors were synthesized by the combination of activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) and ring-opening polymerization (ROP) techniques. The molecular structures and characteristics were confirmed by GPC, (1)H NMR, and FT-IR. The critical micelle concentration (CMC) values of PLA-b-PMAA-b-PPEGMA in aqueous medium varied from 1.4 to 2.6 mg/L, and the partition equilibrium constant (K(v)) of pyrene in micellar solutions ranged from 2.873 × 10(5) to 3.312 × 10(5). The average sizes of the self-assembled blank and drug-loaded micelles were 140-250 nm determined by DLS in aqueous solution. The morphology of the micelles was found to be spherical by SEM. Nifedipine (NFD), a poorly water-soluble drug, was selected as the model drug and wrapped into the core of micelles via dialysis method. The in vitro release behavior of NFD from the micelles was pH-dependent. In simulated gastric fluid (SGF, pH 1.2), the cumulative release percent of NFD was relative low, while in simulated intestinal fluid (SIF, pH 7.4), more than 96% was released within 24 h. All the results showed that the pH-sensitive PLA-b-PMAA-b-PPEGMA micelle may be a prospective candidate as oral drug delivery carrier for hydrophobic drugs with controlled release behavior.

pH-Sensitive micelles self-assembled from amphiphilic copolymer brush for delivery of poorly water-soluble drugs.

A novel pH-sensitive amphiphilic copolymer brush poly(methyl methacrylate-co-methacrylic acid)-b-poly(poly(ethylene glycol) methyl ether monomethacrylate) [P(MMA-co-MAA)-b-PPEGMA] was defined and synthesized by atom transfer radical polymerization (ATRP) technique. The molecular structures and characteristics of this copolymer and its precursors were confirmed by (1)H NMR, FT-IR, and GPC. The CMC of P(MMA-co-MAA)-b-PPEGMA in aqueous medium was determined to be 1-4 mg/L. This copolymer could self-assemble into micelles in aqueous solution with an average size of 120-250 nm determined by DLS. The morphologies of the micelles were found to be spherical by SEM and TEM. Ibuprofen (IBU), a poorly water-soluble drug, was selected as the model drug and wrapped into the core of micelles via dialysis method. Drug entrapment efficiency reached to 90%. The in vitro release behavior of IBU from these micelles was pH-dependent. The cumulative release percent of IBU was less than 20% of the initial drug content in simulated gastric fluid (SGF, pH 1.2) over 12 h, but 90% was released in simulated intestinal fluid (SIF, pH 7.4) within 6 h. The release profiles showed that the P(MMA-co-MAA)-b-PPEGMA micelles could inhibit the premature burst drug release under the intestinal conditions. All the results indicate that the P(MMA-co-MAA)-b-PPEGMA micelle may be a potential oral drug delivery carrier for poorly water-soluble drugs.

Triclosan inhibits the activation of human periodontal ligament fibroblasts induced by lipopolysaccharide from Porphyromonas gingivalis.

Periodontitis is a highly prevalent, chronic, non-specific, and immunologically devastating disease of periodontal tissues, caused by microbial infection. This study aims to examine the efficacy and protective mechanism of triclosan (TCS), a bisphenolic, non-cationic component of oral care products, against periodontal inflammation induced by lipopolysaccharide purified from Porphyromonas gingivalis (LPS-PG). TCS markedly downregulated interleukin-6 (IL-6), IL-8, and IL-15 in human periodontal ligament fibroblasts (HPDLFs) treated with LPS-PG. By using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach, 318 differentially expressed proteins (161 upregulated and 157 downregulated) were identified in TCS-pretreated HPDLFs. TCS upregulated HSPA5 and HSP90B1 but downregulated HSPA2. Besides, TCS upregulated miR-548i in HPDLFs, which downregulated IL-15. These results indicate that TCS attenuates the activation of HPDLFs and downregulates the inflammatory cytokines through various mechanisms, thus highlighting its protective role in periodontal inflammation.

Th2 cell regulatory and effector molecules single nucleotide polymorphisms and periodontitis.

To investigate the association between T helper 2 (Th2) cell regulatory and effector molecules' genetic polymorphisms and periodontitis. Single nucleotide polymorphisms (SNPs) of 11 Th2 cell regulatory or effector molecules genes (CD28, CTLA4, IL4, IL5, IL6, IL9, IL10, IL13, IL4R, GATA3, STAT6, and rs1537415; total 130 SNPs) were studied in Chinese nonsmokers (163 periodontitis-free controls, 141 periodontitis patients) using Sequenom iPlex assays. SNPs potentially associated with periodontitis (adjusted allelic P < 0.1) in this cross-sectional study were further investigated via meta-analysis. Allele G of rs4553808 in promoter of CTLA4 was more frequently detected in periodontitis than controls (P < 0.005), but did not remain significant after age and gender adjustment. Haplotype (GTT) in a block of three CTLA4 SNPs (rs4553808, rs16840252, rs5742909) was significantly associated with periodontitis. Meta-analysis of SNPs identified indicated allele T of CTLA4 rs5742909 (3 studies; 461 control, 369 periodontitis) and allele G of IL6 rs1800796 (18 studies; 2760 control, 2442 periodontitis) were significantly associated with periodontitis (OR = 1.44 and OR = 1.30, respectively). Within limitations of this study, a haplotype of CTLA4 concerning Th2 cell regulation, may be associated with periodontitis in Chinese nonsmokers followed. Meta-analysis indicated rs5742909 of CTLA4 and rs1800796 of IL6 appeared significantly associated with periodontitis.

pH-sensitive micelles self-assembled from multi-arm star triblock co-polymers poly(ε-caprolactone)-b-poly(2-(diethylamino)ethyl methacrylate)-b-poly(poly(ethylene glycol) methyl ether methacrylate) for controlled anticancer drug delivery.

A series of amphiphilic 4- and 6-armed star triblock co-polymers poly(ε-caprolactone)-b-poly(2-(diethylamino)ethyl methacrylate)-b-poly(poly(ethylene glycol) methyl ether methacrylate) (4/6AS-PCL-b-PDEAEMA-b-PPEGMA) were developed by a combination of ring opening polymerization and continuous activators regenerated by electron transfer atom transfer radical polymerization. The critical micelle concentration values of the star co-polymers in aqueous solution were extremely low (2.2-4.0mgl(-1)), depending on the architecture of the co-polymers. The self-assembled blank and doxorubicin (DOX)-loaded three layer micelles were spherical in shape with an average size of 60-220nm determined by scanning electron microscopy and dynamic light scattering. The in vitro release behavior of DOX from the three layer micelles exhibited pH-dependent properties. The DOX release rate was significantly accelerated by decreasing the pH from 7.4 to 5.0, due to swelling of the micelles at lower pH values caused by the protonation of tertiary amine groups in DEAEMA in the middle layer of the micelles. The in vitro cytotoxicity of DOX-loaded micelles to HepG2 cells suggested that the 4/6AS-PCL-b-PDEAEMA-b-PPEGMA micelles could provide equivalent or even enhanced anticancer activity and bioavailability of DOX and thus a lower dosage is sufficient for the same therapeutic efficacy. The results demonstrate that the pH-sensitive multilayer micelles could have great potential application in delivering hydrophobic anticancer drugs for improved cancer therapy.

Self-assembled pH-responsive MPEG-b-(PLA-co-PAE) block copolymer micelles for anticancer drug delivery.

A series of amphiphilic pH-responsive poly (ethylene glycol) methyl ether-b-(poly lactic acid-co-poly (ß-amino esters)) (MPEG-b-(PLA-co-PAE)) block copolymers with different PLA/PAE ratios were designed and synthesized via a Michael-type step polymerization. The molecular structures of the copolymers were confirmed with (1)H NMR and gel permeation chromatography (GPC). These amphiphilic copolymers were shown to self-assemble into core/shell micelles in aqueous solution at low concentrations, and their critical micelle concentrations (CMC) in water were 1.2-9.5 mg/L. The pH-responsive PAE segment was insoluble at pH 7.4, but it became positively charged and soluble via protonation of amino groups at pH lower than 6.5. The average particle size and zeta potential of micelles increased from 180 nm and 15 mV to 220 nm and 40 mV, respectively, when the pH decreased from 7.4 to 5.0. Doxorubicin (DOX) was loaded into the core of these micelles with a high drug loading of 18%. The in vitro DOX release from the micelles was significantly accelerated when solution pH decreased from 7.4 to 5.0. DOX release in the first 10 h appeared to follow Fickian diffusion mechanism. Toxicity test showed that the copolymers had low toxicity whereas the DOX-loaded micelles remained high cytotoxicity for HepG2 cells. The results indicate the pH-sensitive MPEG-b-(PLA-co-PAE) micelle may be a potential hydrophobic drug delivery carrier for cancer targeting therapy with sustained release.

Mesoscopic simulations on the aggregation behavior of pH-responsive polymeric micelles for drug delivery.

Computer simulations, dissipative particle dynamics (DPD) and mesoscopic dynamics (MesoDyn), are performed to study the aggregation behavior of pH-sensitive micelles self-assembled from amphiphilic polymer poly(methyl methacrylate-co-methacrylic acid)-b-poly(poly-(ethylene glycol) methyl ether monomethacrylate), P(MMA-co-MAA)-b-PPEGMA. Ibuprofen (IBU) is selected as the model drug. It can be seen from DPD simulations that P(MMA-co-MAA)-b-PPEGMA and IBU form spherical core-shell micelles at certain compositions, and IBU molecules distribute inside the core formed by hydrophobic MMA. The polymer molecules aggregate first, and then IBU diffuses into the aggregate, forming drug-loaded nanoparticles. With different compositions of polymer and IBU, aggregate morphologies in water are observed as sphere, column and lamella. From MesoDyn results, with less hydrophobic MMA beads, the polymer chains are more difficult to form ordered aggregates, and the order parameters get equilibrated in a longer time. The pH value also affects the aggregate process. At pH<5, the polymer could form traditional core-shell micelles. But at pH>5, the morphology of micelles is found to be anomalous and loose for releasing drug. MAA aggregates on the surface, instead of the inside. The simulation results are qualitatively consistent with the experimental results.