With the emergence of DNA nanotechnology in the 1980s, self-assembled DNA nanostructures have attracted considerable attention worldwide due to their inherent biocompatibility, unsurpassed programmability, and versatile functions. Especially promising nanostructures are tetrahedral framework nucleic acids (tFNAs), first proposed by Turberfield with the use of a one-step annealing approach. Benefiting from their various merits, such as simple synthesis, high reproducibility, structural stability, cellular internalization, tissue permeability, and editable functionality, tFNAs have been widely applied in the biomedical field as three-dimensional DNA nanomaterials. Surprisingly, tFNAs exhibit positive effects on cellular biological behaviors and tissue regeneration, which may be used to treat inflammatory and degenerative diseases. According to their intended application and carrying capacity, tFNAs could carry functional nucleic acids or therapeutic molecules through extended sequences, sticky-end hybridization, intercalation, and encapsulation based on the Watson and Crick principle. Additionally, dynamic tFNAs also have potential applications in controlled and targeted therapies. This review summarized the latest progress in pure/modified/dynamic tFNAs and demonstrated their regenerative medicine applications. These applications include promoting the regeneration of the bone, cartilage, nerve, skin, vasculature, or muscle and treating diseases such as bone defects, neurological disorders, joint-related inflammatory diseases, periodontitis, and immune diseases.
Nucleic Acids/chemistry* ; Regenerative Medicine ; Consensus ; Reproducibility of Results ; DNA/chemistry*

As a novel branch of combinational chemistry, dynamic combinatorial chemistry (DCC) can be viewed as a technique which combines library synthesis and screening in one pot. By addition of molecular target, ligangds, which show binding affinity or strong interaction with the molecular target, can be amplified an young but rapidly growing branch of combinatorial chemistry, has been widely used in organic chemistry, biochemistry, material fields. Ligands in the library can be amplified, since synthesis of the library is screened by a molecular target. Therefore, these structures could be identified easily. Consequently DCC has been widely used in the lead discovery, material chemistry and other fields. On the basis of the principle and method of DCC, this review emphasizes the three factors of DCC, including molecular targets (bio-enzyme, lectin, nucleic acid, organic molecule, inorganic molecule); reaction (disulphide chemistry, ammoniation reduction reaction, hydrazone chemistry, etc.) and analytical method. Meanwhile, limitation, current situation and future development of DCC were also discussed in this paper.
Combinatorial Chemistry Techniques ; methods ; Enzymes ; chemistry ; Lectins ; chemistry ; Nucleic Acids ; chemistry

Peptide nucleic acid (PNA) is a DNA surrogate in which the phosphate deoxyribose backbone of DNA is replaced by repeating N-(2-aminoethyl)glycine units. PNA can hybridize to the complementary DNA and RNA with higher affinity than their oligonucleotide counterparts. This character of PNA not only makes it a new tool for the studies of molecular biology but also the potential candidate for gene-targeting drugs. The non-ionic backbone of PNA leads to stable hybrids with the nucleic acids, but at the same time, the neutral backbone results in poor cellular uptake. To address this problem, studies on modified PNA progress rapidly in recent years. We reviewed literature reports combined with our study about the delivery methods, including backbone modified PNA and PNA-ligand conjugates, and the cellular uptake of modified PNA. In addition, we summarized the problems and future prospect of the cellular delivery of modified PNA.
DNA, Complementary ; Drug Delivery Systems ; Glycine ; analogs & derivatives ; Humans ; Nucleic Acid Hybridization ; Oligonucleotides ; Peptide Nucleic Acids ; chemistry ; RNA

Both the primed in situ (PRINS) and the peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) techniques constitute alternatives to the conventional (fluorescence in situ hybridization, FISH) procedure for chromosomal investigations. The PRINS reaction is based on the use of a DNA polymerase and labeled nucleotide in an in situ primer extension reaction. Peptide nucleic acid probes are synthetic DNA analogs with uncharged polyamide backbones. The two procedures present several advantages (specificity, rapidity and discriminating ability) that make them very attractive for cytogenetic purposes. Their adaptation to human spermatozoa has allowed the development of new and fast procedures for the chromosomal screening of male gametes and has provided efficient complements to FISH for in situ assessment of aneuploidy in male gametes.
Aneuploidy ; Humans ; Male ; Peptide Nucleic Acids ; chemistry ; Primed In Situ Labeling ; methods ; Spermatozoa ; metabolism

Liposome-mediated nucleic acid delivery has been a focus recently, but in the course of delivering nucleic acid, some hurdles seriously limit the nucleic acid exerting treatment effect. This review refers to a series of problems such as low blood stability, reticuloendothelial system absorption, the lower targeting of liposome and the restriction of endosomal escape which are suffered in liposome-mediated nucleic acid delivery; and gives a detail introduction of strategies such as PEGylation, ligand modification, photochemical internalization, the application of degradation liposome and membrane-lytic peptide, to overcome those problems.
Animals ; Humans ; Liposomes ; chemistry ; pharmacokinetics ; Mononuclear Phagocyte System ; metabolism ; Nanoparticles ; Nucleic Acids ; chemistry ; pharmacokinetics ; Photochemical Processes ; Polyethylene Glycols ; chemistry ; pharmacokinetics ; Polymers ; chemistry

OBJECTIVETo Prepare surface functional magnetic microspheres for the separation of vascular endothelial growth factor (VEGF) nucleic acid and lactase enzyme immobilization.

METHODSUsing suspension polymerization methods to copolymerize MA-styrene containing magnetite nanoparticles and GMA-styrene also containing magnetite nanoparticles, respectively. Both the carboxyl-modified magnetic microspheres and epoxy-modified magnetic microspheres were obtained. In addition, the chloromethyl-modified magnetic microspheres were prepared by seedy microemulsion. The magnetic microspheres bound with b-gamma IgG were determined by radioimmunoassay (RIA), and the separation of VEGF nucleic acid and lactase enzyme immobilization were performed by carboxyl-modified magnetic microspheres.

RESULTSTransmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS) and infrared (IR) spectra showed that the products of polymer magnetic microspheres were monodispersed and that the magnetic particles were uniformly distributed in the microsphere with special functional group on the surface of the microsphere. RIA showed that three kinds of magnetic microspheres could be bound with b-gamma IgG and the absorption of b-gamma IgG reached 75 micrograms/mg, especially for the carboxyl-modified magnetic microspheres. The carboxyl-modified magnetic microspheres can be used for the separation of VEGF nucleic acid by coupling with corresponding primer. Moreover, the immobilized enzyme was proportional to the amount of the carboxyl-modified magnetic microspheres.

CONCLUSIONSThe surface functional magnetic polymer microspheres can be bound with active bio-substance, and have a wide application prospect in the fields of biology and medicine.

Adsorption ; Endothelial Growth Factors ; chemistry ; Enzymes, Immobilized ; Immunoglobulin G ; Lactase ; metabolism ; Magnetics ; Microspheres ; Nanotechnology ; Nucleic Acids ; isolation & purification ; Particle Size

OBJECTIVETo investigate the characteristics of freshly resected laryngeal carcinoma by Fourier transform infrared spectroscopy (FTIR).

METHODSFTIR was applied to the study of the cancerous tissues and adjacent normal tissues in 32 patients.

RESULTSCompared with pathological diagnosis results, one benign specimen was classified as a malignant, the accuracy was 98.4%. Significant differences were seen in the FTIR spectra between the normal and malignant laryngeal tissues. The peak at 1085 cm(-1) shift to 1114 cm(-1) showed that the relative contents of DNA in laryngeal carcinoma cells was increased. The peak at 1397 cm(-1) was stronger than 1451 cm(-1) in normal tissues, while it was not obvious in cancer tissues. I(2926)/I(2870) in carcinoma cells was lower than that in normal tissues. The wave numbers of the bands of amide I and amide II, symmetric and asymmetric stretching bands of CH(3), stretching vibration bands of C-OH and NH band were shifted to higher number in cancer tissues.

CONCLUSIONThe study shows that the malignant and normal laryngeal tissues have different FTIR spectra, which are mainly due to changes in protein, nucleic acid and phospholipids. FTIR may become a new method for the diagnosis of laryngeal carcinoma in clinical practice.

Humans ; Laryngeal Neoplasms ; chemistry ; diagnosis ; pathology ; Larynx ; chemistry ; pathology ; Neoplasm Proteins ; analysis ; Nucleic Acids ; analysis ; Phospholipids ; analysis ; Spectroscopy, Fourier Transform Infrared ; methods

To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG-PSN) and thymopeptides on T-lymphocytes of normal and immunosuppressed mice, CD4+ and CD8+ T-lymphocyte subsets of single nucleic cell in thymus, spleen and peripheral blood were detected successively by flow cytometry after application of BCG-PSN and thymopeptides. Meanwhile, CD4+/CD8+ ratio was also calculated. The results showed that both BCG-PSN and thymopeptides could decrease the proportion of CD4+ CD8+ T-lymphocyte subsets in the thymus, at the same time increase CD4+ T-lymphocyte, CD8+ T-lymphocyte proportion in the three tissues. The fluctuation in amplitude was greater in thymopeptides group than that in BCG-PSN group. It is concluded that acting location of thymopeptides is in thymus, its stimulating action is stronger than that of BCG-PSN, while BCG-PSN not only accelerates the differentiation in thymus, but also has some direct stimulation to peripheral CD4+ T-lymphocytes, and can maintain CD4+/CD8+ ratio within normal range. So, BCG-PSN is safer.
Adjuvants, Immunologic/*pharmacology ; Immunocompromised Host ; Mycobacterium bovis/*chemistry ; Nucleic Acids/pharmacology ; Peptide Fragments/*pharmacology ; Polysaccharides, Bacterial/*pharmacology ; T-Lymphocyte Subsets/*drug effects ; Thymus Gland/chemistry

The lipid droplet (LD) is a unique multi-functional organelle that contains a neutral lipid core covered with a phospholipid monolayer membrane. The LDs have been found in almost all organisms from bacteria to humans with similar shape. Several conserved functions of LDs have been revealed by recent studies, including lipid metabolism and trafficking, as well as nucleic acid binding and protection. We summarized these findings and proposed a hypothesis that the LD is a conserved organelle.
Animals ; Bacteria ; metabolism ; ultrastructure ; Biological Evolution ; Cholesterol Esters ; metabolism ; Humans ; Lipid Droplets ; chemistry ; metabolism ; ultrastructure ; Lipid Metabolism ; genetics ; Nucleic Acids ; metabolism ; Peptide Initiation Factors ; chemistry ; metabolism ; Protein Binding ; RNA-Binding Proteins ; chemistry ; metabolism ; Ribosome Subunits ; chemistry ; metabolism ; Triglycerides ; metabolism

To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG-PSN) and thymopeptides on T-lymphocytes of normal and immunosuppressed mice, CD4+ and CD8+ T-lymphocyte subsets of single nucleic cell in thymus, spleen and peripheral blood were detected successively by flow cytometry after application of BCG-PSN and thymopeptides. Meanwhile, CD4+/CD8+ ratio was also calculated. The results showed that both BCG-PSN and thymopeptides could decrease the proportion of CD4+ CD8+ T-lymphocyte subsets in the thymus, at the same time increase CD4+ T-lymphocyte, CD8+ T-lymphocyte proportion in the three tissues. The fluctuation in amplitude was greater in thymopeptides group than that in BCG-PSN group. It is concluded that acting location of thymopeptides is in thymus, its stimulating action is stronger than that of BCG-PSN, while BCG-PSN not only accelerates the differentiation in thymus, but also has some direct stimulation to peripheral CD4+ T-lymphocytes, and can maintain CD4+/CD8+ ratio within normal range. So, BCG-PSN is safer.
Adjuvants, Immunologic ; pharmacology ; Animals ; Female ; Immunocompromised Host ; Male ; Mice ; Mycobacterium bovis ; chemistry ; Nucleic Acids ; pharmacology ; Peptide Fragments ; pharmacology ; Polysaccharides, Bacterial ; pharmacology ; T-Lymphocyte Subsets ; drug effects ; Thymus Gland ; chemistry