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Background: Polynucleotides stimulate collagen formation and are used clinically to enhance elasticity. In this study, we investigated current practices and perceived effectiveness of polynucleotide injection treatment for enlarged facial pores among cosmetic physicians. Materials and Methods: A survey was developed to investigate clinicians' use and effectiveness of polynucleotides in the treatment of enlarged facial pores. This survey was distributed to clinicians at the Korean Aesthetic Surgery & Laser Society Autumn Symposium. Results: A total of 407 physicians who used polynucleotides for enlarged facial pores were enrolled in the survey. Polynucleotides were used by 75.7%, 87.7%, and 72.2% of physicians for enlarged facial pores caused by excessive sebum production, reduced elasticity, and acne, respectively. Among those users, 81.4%, 83.8%, and 76.8% in those same categories, respectively, responded that polynucleotides were "very effective" or "effective." Furthermore, most clinicians combined polynucleotides with microneedle radiofrequency as energy‐based devices and with botulinum toxin as injection therapy. Conclusion: This study highlights the widespread use and perceived efficacy of polynucleotide injection among cosmetic physicians in the Republic of Korea for enlarged facial pores due to excessive sebum production, reduced elasticity, and acne. Positive feedback from practitioners supports the benefits of using polynucleotides in enlarged facial pore treatment. [ABSTRACT FROM AUTHOR]

Polynucleotides, complex molecules composed of nucleotides, have gained attention in aesthetic medicine for their potential to regulate gene expression and promote tissue regeneration. This review aims to provide an overview of the current practices and perceived effectiveness of polynucleotides in aesthetic medicine. A comprehensive search of the literature was conducted using keywords related to polynucleotides, cosmetic application, and aesthetic application. Studies were selected based on their relevance to aesthetic medicine and the inclusion of human subjects. The review found that polynucleotides have been used to improve skin texture, reduce wrinkle depth, and enhance facial appearance. The studies reported varying degrees of efficacy and safety, with some studies demonstrating significant improvements in skin elasticity and hydration. However, others reported limited or no benefits. The review also highlighted the need for further research to establish the optimal use and efficacy of polynucleotides in aesthetic medicine. While the existing literature suggests that polynucleotides may have potential benefits in aesthetic medicine, more research is needed to fully understand their mechanisms of action and optimal use. Clinicians should be aware of the current limitations and potential risks associated with the use of polynucleotides in aesthetic medicine. [ABSTRACT FROM AUTHOR]

Background: Polynucleotides (PDRN) have gained attention in aesthetic and regenerative medicine for their potential to enhance tissue regeneration, improve skin quality, and deliver superior aesthetic outcomes. However, the transition from theoretical benefits to proven clinical outcomes faces challenges due to inconsistencies and methodological shortcomings in the existing evidence base. This systematic review aims to critically evaluate the scientific basis and empirical evidence supporting the use of PDRN in aesthetic and regenerative medicine, highlighting the quality, reproducibility, and reliability of existing research, and identifying gaps and inconsistencies within the current literature. Methods: Adhering to PRISMA guidelines and registered with PROSPERO, this review formulated a research question using the PICO framework to assess the efficacy of PDRN applications. A comprehensive literature search across PubMed–MEDLINE, EMBASE, and Web of Science was conducted. The inclusion criteria focused on clinical studies applying PDRN in regenerative or aesthetic medicine with clear outcome measures. Quality assessment utilized Cochrane Risk of Bias tool, ROBINS-I, and Newcastle Ottawa Scale. Data synthesis was qualitative due to anticipated heterogeneity. Results: From 360 identified studies, 16 clinical trials met the inclusion criteria, encompassing various study designs and a total of 750 participants. The studies investigated PDRN's efficacy across different conditions and applications. Findings revealed a lack of specificity in PDRN sequencing, molecular targets, and dosage details, with a noted variability in source and manufacturing standards. Most studies demonstrated a low risk of bias, suggesting methodological rigor, yet the absence of comprehensive reporting on sequencing, targeted mechanisms, and molecular length was evident. The review underscores the embryonic stage of PDRN research and the necessity for more rigorous studies to validate clinical outcomes. Conclusions: The potential of PDRN in aesthetic and regenerative medicine is significant, yet the current state of evidence necessitates a cautious and evidence-based approach to their clinical integration. Future research should focus on overcoming the highlighted gaps and inconsistencies, ensuring that the innovation in treatments does not compromise patient safety and efficacy. Regulatory frameworks must evolve to address the unique challenges presented by PDRN technologies, ensuring their safe and ethical application. Level of evidence: Level I, Therapeutic. [ABSTRACT FROM AUTHOR]

In recent years, biopolymer-based nano-drug delivery systems with antioxidative properties have gained significant attention in the field of pharmaceutical research. These systems offer promising strategies for targeted and controlled drug delivery while also providing antioxidant effects that can mitigate oxidative stress-related diseases. Generally, the healthcare landscape is constantly evolving, necessitating the continual development of innovative therapeutic approaches and drug delivery systems (DDSs). DDSs play a pivotal role in enhancing treatment efficacy, minimizing adverse effects, and optimizing patient compliance. Among these, nanotechnology-driven delivery approaches have garnered significant attention due to their unique properties, such as improved solubility, controlled release, and targeted delivery. Nanomaterials, including nanoparticles, nanocapsules, nanotubes, etc., offer versatile platforms for drug delivery and tissue engineering applications. Additionally, biopolymer-based DDSs hold immense promise, leveraging natural or synthetic biopolymers to encapsulate drugs and enable targeted and controlled release. These systems offer numerous advantages, including biocompatibility, biodegradability, and low immunogenicity. The utilization of polysaccharides, polynucleotides, proteins, and polyesters as biopolymer matrices further enhances the versatility and applicability of DDSs. Moreover, substances with antioxidative properties have emerged as key players in combating oxidative stress-related diseases, offering protection against cellular damage and chronic illnesses. The development of biopolymer-based nanoformulations with antioxidative properties represents a burgeoning research area, with a substantial increase in publications in recent years. This review provides a comprehensive overview of the recent developments within this area over the past five years. It discusses various biopolymer materials, fabrication techniques, stabilizers, factors influencing degradation, and drug release. Additionally, it highlights emerging trends, challenges, and prospects in this rapidly evolving field. [ABSTRACT FROM AUTHOR]

Background: The concept of "skin boosters" has evolved, marking a shift from traditional uses of hyaluronic acid (HA) fillers primarily for augmenting skin volume to a more diverse application aimed at improving dermal conditions. Restylane Vital and other HA fillers have been repurposed to combat skin aging and wrinkles by delivering HA directly to the dermis. Objectives: This review aims to define the term "skin booster" and to discuss the various components that constitute skin boosters. It seeks to provide a comprehensive overview of the different ingredients used in skin boosters, their roles, and their impact on enhancing dermal conditions. Methods: A comprehensive review was conducted, focusing on representative skin booster ingredients. The approach involved analyzing the different elements used in skin boosters and their specific roles in enhancing dermal improvement. Results: The findings indicate that skin boosters, encompassing a range of ingredients, are effective in improving the condition of the skin's dermis. The review identifies key ingredients in skin boosters and their specific benefits, including hydration, elasticity improvement, and wrinkle reduction. Conclusions: Skin boosters represent a significant development in dermatological treatments, offering diverse benefits beyond traditional HA fillers. This review provides valuable insights into the constituents of skin boosters and their effectiveness, aiding readers in making informed decisions about these treatments. The potential of skin boosters in dermatological practice is considerable, warranting further research and application. [ABSTRACT FROM AUTHOR]

Background: An intradermal injection is a medical procedure that involves administering a small amount of medication or substance into the dermal layer of the skin. This research focused on identifying the most suitable injection needle for precise intradermal administration of skin boosters. Methods: The study involved conducting intradermal injections on four cadavers and participants using a 2 mm length, 34‐gauge needle (N‐Finders, Inc., South Korea). During the cadaveric study, the polynucleotide prefilled syringe was dyed green, and an anatomist performed dissections, removing only the skin layer. Ultrasonographic observations were carried out to ensure accurate intradermal injection placement. Results: In all four cadavers, the facial injections at the anterior cheek region were precisely administered intradermally at a 30‐degree injection angle. However, the 90‐degree injection was found just below the dermal layer upon skin layer removal. Discussion: The findings suggest that using a 2 mm needle length allows for easy and convenient intradermal injections. [ABSTRACT FROM AUTHOR]

Background: Polynucleotides (PN) are increasingly used for the treatment of facial erythema in the Republic of Korea. However, there are limited pre‐clinical and clinical data on the efficacy of polynucleotides for facial erythema. In this study, we investigated the current practice and perceived effectiveness of polynucleotide treatment for facial erythema among cosmetic physicians. Methods: By conducting a survey among clinicians who use PN in clinical practice, we explored the current practices and assessed the perceived effectiveness of polynucleotides in treating facial erythema. Results: A total of 557 physicians who used polynucleotides for facial erythema participated in the survey. Polynucleotides were used by 84.4%, 66.4%, and 47.4% of physicians for facial erythema caused by inflammatory facial dermatosis, repeated laser/microneedle radiofrequency, and steroid overuse, respectively. Among those users, 88.1%, 90%, and 83.7% respectively in those same categories answered that polynucleotides were "highly effective" or "effective." Furthermore, they agreed that polynucleotides have the following properties: wound healing/regeneration (95.8%), protection of skin barrier (92.2%), hydration (90.5%), vascular stabilization (81.0%), and anti‐inflammation (79.5%). Conclusion: Our findings showed that cosmetic physicians in the Republic of Korea have used PN as a part of combination treatment for facial erythema resulting from inflammatory facial dermatosis and repeated laser/ microneedle radiofrequency, rather than from steroid overuse. Also, most clinicians agreed that PN was effective for treatment of facial erythema. Given the lack of pre‐clinical and clinical trial evidence, the empirical responses of practicing physicians provide useful information to guide clinical practice and further research. [ABSTRACT FROM AUTHOR]

Purpose: This observational study was conducted to confirm the effectiveness and safety of intra-articular injection of polynucleotides in Korean patients with knee osteoarthritis (OA) in a real clinical setting. Materials and Methods: Five hundred and forty-six cases of patients who received three-five times of injections of polynucleotides within six months and then visited were enrolled from December 2020 to February 2022. The subjects were then followed up for six months. The pain reduction effect was evaluated using a 100 mm-weight bearing pain visual analogue scale (VAS) before administration, immediately after administration, and three and six months after the injection cycle. Then the results were analyzed as an entire group and sub-group. In addition, the tendency of Clinical Global Impression (CGI) and the Patient Global Impression (PGI) at each time point and adverse events were investigated. Results: An analysis of the VAS in the entire group analysis revealed a more than 50% reduction of pain vs. pre-administration that was maintained for six months from the end of the Conjuran® treatment. Approximately 40%-60% reductions of pain were observed in subgroup analysis according to age, Kellgren-Lawrence (KL)-grade, and pain at pre-administration. At all time points, these pain relief effects were significant (p<0.001) compared to pre-administration, regardless of any factors of sub-group analysis. Moreover, in CGI, 77.8% of patients reported that their symptoms improved after six months from the completion of treatment. In addition, in PGI, 75.6% of patients self-evaluated that the symptoms improved after six months from the completion of treatment. No serious adverse events were reported. Conclusion: An intra-articular injection of polynucleotides to knee OA patients in the clinical field showed significant pain reduction effectiveness for six months after treatment, and no other serious case was reported. Therefore, this is considered a therapeutical option in an intra-articular injection that can be used safely in a real clinical setting. In particular, sub-analysis of the factors considered to affect the symptoms of knee OA, such as age, KL-grade, and pain level before administration, revealed significant pain improvement in all factors and aspects. Therefore, intra-articular injection of polynucleotides is expected to be an effective therapeutic option in knee OA. [ABSTRACT FROM AUTHOR]

Polynucleotides, DNA and RNA (mRNA and non‐coding RNAs) are critically involved in the molecular pathways of disease. Small molecule binding interactions with polynucleotides can modify functional polynucleotide topologies and/or their interactions with proteins. Current approaches to library design (lead‐like or fragment‐like libraries) are based on protein‐ligand interactions and often include careful consideration of the 3‐dimensional orientation of binding motifs and exclude π‐rich compounds (polyfused aromatics) to avoid off‐target R/DNA interactions. In contrast to proteins, where π,π‐interactions are weak, polynucleotides can form strong π,π‐interactions with suitable π‐rich ligands. To assist in designing a polynucleotide‐biased library, a scaffold‐divergent synthesis approach to polyfused aromatic scaffolds has been undertaken. Initial screening hits that form moderately stable polynucleotide‐ligand‐protein ternary complexes can be further optimized through judicious incorporation of substituents on the scaffold to increase protein‐ligand interactions. An example of this approach is given for topoisomerase‐1 (TOP1), generating a novel TOP1 inhibitory chemotype. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the safety and efficacy of vulvovaginal intradermal injections of polynucleotides (PN) combined with hyaluronic acid (HA) in postmenopausal women affected by vulvovaginal atrophy (VVA). Postmenopausal women affected by VVA were treated with vulvar and vaginal intradermal injections of one prefilled syringe of 2 ml PN/HA every 2 weeks for four sessions. Patients were evaluated at T0 (baseline), T1 (after session 4) and T2 (1 month after session 4). Evaluation of the treatment was assessed by three international validated questionnaires: Vaginal Health Index (VHI), Vulvar Health Index (VuHI) and Female Sexual Function Index (FSFI). The Wilcoxon matched-paired signed-rank test was used to compare the differences in VHI, VuHI, FSFI and FSFI domains within the groups. Statistical significance was set at p < 0.05. Fifty patients were included in the study (mean age 59.9 ± 7.6 years). Overall, the VHI, VuHI and FSFI reported statistically significant differences between baseline and T1 (p < 0.001) and between baseline and T2 (p < 0.001). All FSFI domains registered a statistically significant increase between baseline and T2 (p < 0.001). No complications or side effects were observed. Vulvovaginal intradermal injection of PN/HA is a safe, effective treatment, is not expensive and is a reproducible procedure in postmenopausal women with VVA. [ABSTRACT FROM AUTHOR]

Introduction: A few studies have evaluated the efficacy and safety of noninsulated radiofrequency microneedling (RFMN) to treat periorbital wrinkles in Asian patients. Recently, wound healing accelerators, polynucleotides (PNs), have received attention in wound management. However, their efficacy and safety have not been fully elucidated following RFNM. This study aimed to evaluate the efficacy and safety of noninsulated RFMN for periorbital wrinkles and the synergistic effect of PNs after RFMN. Methods: Thirty subjects with Fitzpatrick skin types III to V and facial wrinkles (Fitzpatrick grades I and II) were enrolled. All volunteers were treated over the entire face with noninsulated RFMN for three sessions at 2-week intervals. The left and right sides of each patient's face were randomly assigned to receive PNs (treatment group) or normal saline solution (control group). The indentation and maximum depth of wrinkles were objectively measured using Antera 3D. Subjective self-evaluations were obtained at baseline, 2 weeks after the third treatment, and at 1, 2, 3, and 6 months after the final treatment. In addition, pain scores, immediate reactions, and other adverse effects were evaluated. Results: Twenty-nine subjects completed the treatment protocol. Most presented with grade II wrinkling (69%). At 2-month follow-up, Antera 3D image analysis revealed faster improvement for the treatment group. At 6-month follow-up, the majority of subjects reported an improvement of 25–75% in their periorbital wrinkles. The average pain score was 2.2 out of 10. No serious adverse events (infection, pigmentary alteration, persistent erythema, or scarring) were observed. Conclusions: Noninsulated RFMN is safe and effective for treating periorbital wrinkles and can be used as a modality for transdermal drug delivery. Topical polynucleotides as an adjunctive treatment provide additional benefits for periorbital wrinkle treatment. Trial Registration Number: TCTR20201105007. [ABSTRACT FROM AUTHOR]

Background: A first-year interim analysis of this two-year study suggested that intra-articular injections of highly purified, natural-origin polynucleotides and hyaluronic acid (HA) as a fixed combination (PNHA) might improve knee function and joint pain more effectively than HA alone in patients with knee osteoarthritis (OA). The purpose of the second-year analysis herein described was to verify whether the first-year interim outcomes persist over the whole two-year period.Methods: Randomised, double-blind, HA-controlled clinical trial in 100 knee OA patients (98 randomised, 79 completing the study) in a high-specialisation tertiary care setting. The hypothesised difference of efficacy between PNHA and HA for the original sample size estimate is 20%. Treatment cycle: three intra-articular knee injections of either PNHA or HA, at baseline and weekly for two weeks.Evaluations: Western Ontario and McMaster Universities (WOMAC) score and Knee Society Score (KSS) as, respectively, primary and secondary endpoints, evaluated at baseline and after 2, 6, 12, and 24 months; synovial fluid levels of mediators (at baseline and the end of the treatment cycle). Adverse effects investigated at each control visit.Statistical Analysis: Kruskal-Wallis test for independent samples (nonparametric one-way analysis of variance) after correction of means for age, Body Mass Index and Kellgren-Lawrence grade. If significant, pairwise post-hoc Sidak multiple comparisons.Results: KSS total score and KSS pain item: significant improvement in both groups, with significantly more pain improvement in patients treated with PNHA (2-point reduction) than HA (1-point reduction). Both groups experienced significant long-term reductions in WOMAC total scores: significantly stronger in PNHA-treated patients after 24 months with a steady difference of 16% favouring PNHA in WOMAC pain subscore. No clinically significant adverse events in either group.Conclusions: The outcomes of the 2-year study confirmed that a short cycle of intra-articular treatment (3 weekly double-blind injections) with polynucleotides (long-acting viscosupplementation properties, chondrocyte activation, pain-relieving properties) in fixed combination with high molecular weight hyaluronic acid is more effective in improving knee function and pain in knee OA patients than HA alone. PNHA may be elective for viscosupplementation in knee OA patients with fastidious and resistant pain and worsening disease.Trial Registration: NCT02417610 . Registration, 15/04/2015. ClinicalTrials.gov database link. [ABSTRACT FROM AUTHOR]

Striae distensae (SD), also known as stretch marks, are observable linear scars that appear where dermal damage has occurred as a result of prolonged stretching of the skin. The actual pathophysiology of SD is still up for debate because its origins are multifaceted. Generally, striae are benign lesions, but larger lesions may get traumatized and become ulcerated or rupture. In patients with edema and receiving systemic steroids, bullous SD could develop secondary to fluid buildup preferentially in striae. We report a case of a young patient with cardiomyopathy who received systemic steroids and developed bullous striae distensae. females being twice as likely to be affected by them.¹ Striae are remarkably prevalent and frequently lead to cosmetic morbidity and psychological frustration, especially in women. It can be caused by physiological as well as pathological factors. Nevertheless, the pathogenesis is still not completely understood.² [ABSTRACT FROM AUTHOR]

Background: Injective procedures using polynucleotides‐based products to promote dermal rejuvenation and revitalization are steadily evolving, yet no structured protocols are available that discuss and provide guidance in aesthetic treatments with highly purified polynucleotides. The goal of this document was to provide consensus‐based recommendations for the safe and effective use of Polynucleotides Highly Purified Technology™ (PN‐HPT™) devices for skin rejuvenation. Patients/Methods: A team of eight experts with extensive experience in treatments for skin rejuvenation and revitalization integrated the best available evidence and clinical judgment and devised a series of practical guidance to support dermatologists, plastic surgeons, and aesthetic physician in the use of PN‐HPT™ products, alone and in combination, in aesthetic medicine. Results: For most items, the expert group achieved a majority consensus. "Recommendations" (consensus >80%) were reached for the face, periocular area, décolleté and neck, hands, scalp, and stretch marks. Recommendations include details of techniques, information on dosage, volumes to be injected, and the ideal number of required treatment sessions, as well as time intervals between them for different areas of face and body. A lower agreement level of 60% was reached on but one item related to the initial treatment cycle for the face, leading to a "Consensus statement" for that area instead of a full "Recommendation." Conclusion: The expert consensus illustrates the value of natural‐origin, highly purified polynucleotides (PN‐HPT™) as biostimulatory booster strategy for skin priming and revitalization of face and body and provides a detailed guide for the use. [ABSTRACT FROM AUTHOR]

Objective: Pain and range of motion loss are the main clinical features of osteoarthritis (OA). Hyaluronic acid (HA) is one of the infiltrative therapies for OA treatment; however, its effectiveness is a matter of an ongoing debate in clinical practice. Polynucleotides (PNs), a DNA-derived macromolecule with natural origin and trophic activity, were found to favor cell growth and collagen production, in preclinical and clinical studies regarding cartilage regeneration. This study aimed at evaluating whether injection of PNs, in combination with HA [PNs associated with HA (PNHA)], can ameliorate pain and function of knees affected by OA, more than HA alone. Design: A randomized, double-blind, controlled clinical trial. Patients: The study enrolled 100 patients, then randomized to receive PNHA or HA alone (3 weekly knee I.A. injections). Interventions and Main Outcome Measures: Pain reduction, decrease of proinflammatory synovial fluid (SF) factors, and improvement in knee function were evaluated by Knee Society Score and WOMAC scores, after 2, 6, and 12 months and by biochemical and immunoenzymatic analyses of SF at the end of the treatment. Results: Knee Society Score total score and pain item significantly ameliorated in both groups, showing better results in PNHA- than in the HA-treated group. A significant reduction in the WOMAC score was observed over time for both groups. No significant adverse events were reported in either group. Conclusions: These findings suggest that I.A. injection of PNs, in combination with HA, is more effective in improving knee function and pain, in a joint affected by OA, compared with HA alone. [ABSTRACT FROM AUTHOR]

The principle of three-dimensional protein structure formation is a long-standing conundrum in structural biology. A globular domain of a soluble protein is formed by a network of atomic contacts among amino acid residues, but regions without intramolecular non-local contacts are often observed in the protein structure, especially in loop, linker, and peripheral segments with secondary structures. Although these regions can play key roles for protein function as interfaces for intermolecular interactions, their nature remains unclear. Here, we termed protein segments without non-local contacts as floating segments and sought them in tens of thousands of entries in the Protein Data Bank. As a result, we found that 0.72% of residues are in floating segments. Regarding secondary structural elements, coil structures are enriched in floating segments, especially for long segments. Interactions with polypeptides and polynucleotides, but not chemical compounds, are enriched in floating segments. The amino acid preferences of floating segments are similar to those of surface residues, with exceptions; the small side chain amino acids, Gly and Ala, are preferred, and some charged side chains, Arg and His, are disfavored for floating segments compared to surface residues. Our comprehensive characterization of floating segments may provide insights into understanding protein sequence-structure-function relationships. [ABSTRACT FROM AUTHOR]

Almost 60 years ago, Severo Ochoa was awarded the Nobel Prize in Physiology or Medicine for his discovery of the enzymatic synthesis of RNA by polynucleotide phosphorylase (PNPase). Although this discovery provided an important tool for deciphering the genetic code, subsequent work revealed that the predominant function of PNPase in bacteria and eukaryotes is catalyzing the reverse reaction, i.e., the release of ribonucleotides from RNA. PNPase has a crucial role in RNA metabolism in bacteria and eukaryotes mainly through its roles in processing and degrading RNAs, but additional functions in RNA metabolism have recently been reported for this enzyme. Here, we discuss these established and noncanonical functions for PNPase and the possibility that the major impact of PNPase on cell physiology is through its unorthodox roles. [ABSTRACT FROM AUTHOR]

After listing functional constraints on what numbers in the brain must do, I sketch the two's complement fixed-point representation of numbers because it has stood the test of time and because it illustrates the non-obvious ways in which an effective coding scheme may operate. I briefly consider its neurobiological implementation. It is easier to imagine its implementation at the cell-intrinsic molecular level, with thermodynamically stable, volumetrically minimal polynucleotides encoding the remembered numbers, than at the circuit level, with plastic synapses encoding them. [ABSTRACT FROM AUTHOR]

Obtaining informative short tandem repeat (STR) profiles from degraded DNA samples is a challenging task usually undermined by locus or allele dropouts and peak-high imbalances observed in capillary electrophoresis (CE) electropherograms, especially for those markers with large amplicon sizes. We hereby show that the current STR assays may be greatly improved for the detection of genetic markers in degraded DNA samples by using long single stranded DNA polynucleotides (ssDNA polynucleotides) as surrogates for PCR primers. These long primers allow a closer annealing to the repeat sequences, thereby reducing the length of the template required for the amplification in fragmented DNA samples, while at the same time rendering amplicons of larger sizes suitable for multiplex assays. We also demonstrate that the annealing of long ssDNA polynucleotides does not need to be fully complementary in the 5’ region of the primers, thus allowing for the design of practically any long primer sequence for developing new multiplex assays. Furthermore, genotyping of intact DNA samples could also benefit from utilizing long primers since their close annealing to the target STR sequences may overcome wrong profiling generated by insertions/deletions present between the STR region and the annealing site of the primers. Additionally, long ssDNA polynucleotides might be utilized in multiplex PCR assays for other types of degraded or fragmented DNA, e.g. circulating, cell-free DNA (ccfDNA). [ABSTRACT FROM AUTHOR]

The transition from prelife where self-replication does not occur, to life which exhibits self-replication and evolution, has been a subject of interest for many decades. Membranes, forming compartments, seem to be a critical component of this transition as they provide several concurrent benefits. They maintain localized interactions, generate electro-chemical gradients, and help in selecting cooperative functions as they arise. These functions pave the way for the emergence and maintenance of simple metabolic cycles and polymers. In the context of origin of life, evolution of information-carrying molecules and RNA based enzymes within compartments has been subject to intensive theoretical and experimental research. Hence, many experimental efforts aim to produce compartments that contain elongating polynucleotides (also referred to as protocells), which store information and perform catalysis. Despite impressive experimental progress, we are still relatively ignorant about the dynamics by which elongating polynucleotides can produce more sophisticated behaviors. Here we perform computer simulations to couple information production through template-free elongation of polymers with dividing compartments. We find that polymers with a simple ability—biasing the concentration of monomers within their own compartment—can acquire a selective advantage in prelife. We further investigate whether such a mechanism allows for cooperative dynamics to dominate over purely competitive ones. We show that under this system of biased monomer addition, even without template-directed self-replication, genetic motifs can emerge, compete, cooperate, and ultimately survive within the population. [ABSTRACT FROM AUTHOR]

This review is a comprehensive analysis of the progress made so far on the delivery of polynucleotide-based therapeutics to the eye, using synthetic nanocarriers. Attention has been addressed to the capacity of different nanocarriers for the specific delivery of polynucleotides to both, the anterior and posterior segments of the eye, with emphasis on their ability to (i) improve the transport of polynucleotides across the different eye barriers; (ii) promote their intracellular penetration into the target cells; (iii) protect them against degradation and, (iv) deliver them in a long-term fashion way. Overall, the conclusion is that despite the advantages that nanotechnology may offer to the area of ocular polynucleotide-based therapies (especially AS-ODN and siRNA delivery), the knowledge disclosed so far is still limited. This fact underlines the necessity of more fundamental and product-oriented research for making the way of the said nanotherapies towards clinical translation. [ABSTRACT FROM AUTHOR]

The endoergic nature of protein and nucleic acid assembly in aqueous media presents two questions that are fundamental to the understanding of life's origins: (i) how did the polymers arise in an aqueous prebiotic world; and (ii) once formed in some manner, how were they sufficiently persistent to engage in further chemistry. We propose here a quantitative resolution of these issues that evolved from recent accounts in which RNA-like polymers were produced in evaporation/rehydration cycles. The equilibrium Nm + Nn ↔ Nm+n + H2O is endoergic by about 3.3 kcal/mol for polynucleotide formation, and the system thus lies far to the left in the starting solutions. Kinetic simulations of the evaporation showed that simple Le Châtelier's principle shifts were insufficient, but the introduction of oligomer-stabilizing factors of 5-10 kcal/mol both moved the process to the right and respectively boosted and retarded the elongation and hydrolysis rates. Molecular crowding and excluded volume effects in present-day cells yield stabilizing factors of that order, and we argue here that the crowded conditions in the evaporites generate similar effects. Oligomer formation is thus energetically preferred in those settings, but the process is thwarted in each evaporation step as diffusion becomes rate limiting. Rehydration dissipates disordered oligomer clusters in the evaporites, however, and subsequent dry/wet cycling accordingly "ratchets up" the system to an ultimate population of kinetically trappedthermodynamically preferred biopolymers. [ABSTRACT FROM AUTHOR]

The article discusses the hypercycle, an abstract model of organization of self-replicating molecules that are connected in a cyclic, autocatalytic manner. Topics covered include the reformulations and methodological approaches to the hypercycle theory, formulation of the model, and the role of ribozymes in hypercycle formulation.

We used the atomistic molecular mechanics method with a well-known universal force field (UFF), as implemented in forcite module, to investigate the fractal properties of the poly G C and poly T A base pairs diluted in solvent, grown in conformity with the quasiperiodic Fibonacci sequence. It was obtained through simulations, and demonstrated that solvent-accessible surface area and volume of these molecules follow power-law behavior that depends on the chain length with exponent near 1 for the volume, and for the surface. The exponents calculated presented a dependence on the solvent probe radius. It was demonstrated that only in a rigid simple model these exponents converge to unity as the chain length increases to infinity. However the reason for fractionary exponents found here could be just attributed to finite size effect, but in fact, the flexibility plays a central rule in a real molecular system, and could explain the fractionary exponents obtained here. Both classes of macromolecules analyzed present a self-similar characteristic that could assist for understanding of several biological properties, and result in a variety of potential applications. [ABSTRACT FROM AUTHOR]

In this work, we were able to obtain the benzothieno[3,2- b ]quinoline 1 and benzothieno[2,3- c ]quinoline 2 using a new one-pot procedure from the reaction of the commercially available 3-bromobenzo[ b ]thiophene-2-carbaldehyde with 2-aminophenylpinacolborane under Suzuki coupling conditions using a stereochemically hindered ligand, 2-(cyclohexylphosphane)biphenyl and Ba(OH) 2 ·8H 2 O as the base. Fluorescence properties of the benzothieno[3,2- b ]quinoline 1 and the benzothieno[2,3- c ]quinoline 2 were studied in solvents of different polarity. Both compounds exhibit a solvent sensitive emission, compound 1 being less fluorescent ( Φ F < 0.05) than compound 2 (0.04 ≤ Φ F ≤ 0.10). The interaction of these compounds with salmon sperm DNA and synthetic double-stranded heteropolynucleotides, poly(dA–dT)·(dA–dT) and poly(dG–dC)·(dG–dC), was studied using spectroscopic methods, allowing the determination of the intrinsic binding constants and binding site sizes. The interaction of both compounds is stronger with adenine–thymine (A–T) base pairs. Compound 1 is the most intercalative in salmon sperm DNA (47%) and polynucleotides (46–49% of intercalated molecules), while for compound 2 , 41% is intercalated in salmon sperm DNA and only 8% in poly(dG–dC)·(dG–dC). Docking studies indicate that compound 1 interacts more strongly with DNA than compound 2 , with a significant value of binding free energy in the case of intercalation. Minor groove binding is also very favourable and, probably, both mechanisms occur with a preponderance of intercalation in the case of compound 1 . Overall, these results indicate that both benzothienoquinolines interact with nucleic acids by both intercalation and groove binding. [ABSTRACT FROM AUTHOR]

Interaction of the anticancer plant alkaloid chelerythrine with four sequence specific synthetic polynucleotides was studied by spectroscopy and calorimetry experiments. The binding resulted in strong hypochromic and bathochromic effects in the absorption spectrum of the alkaloid, enhancement in the fluorescence with the AT polynucleotides and the homo-GC polynucleotide and quenching with the hetero-GC polynucleotide. Cooperative binding was observed with all the polynucleotides. Fluorescence polarization anisotropy, iodide quenching and viscosity results confirmed intercalative binding of the alkaloid. The binding resulted in the thermal stabilization of the polynucleotides and moderate perturbations in the B-conformation of the DNA. The high binding affinity values (~106 M-1) evaluated from the spectroscopic data was in excellent agreement with those obtained from calorimetry. The binding was exothermic and favoured by negative standard molar enthalpy and positive standard molar entropic contributions in all cases other than homo-AT polynucleotide, where it was endothermic and entropy driven. Salt-dependent calorimetry data revealed that the binding reaction was driven mostly by non-polyelectrolytic forces. The magnitude of the negative heat capacity values confirmed the role of significant hydrophobic effects in the interaction profile of the alkaloid with the polynucleotides. The results revealed the specificity of chelerythrine to follow homo-GC > hetero-GC > hetero-AT = homo-AT polynucleotide. [ABSTRACT FROM AUTHOR]

The multi S1/P1 nuclease AtBFN2 (EC 3.1.30.1) encoded by the Arabidopsis thaliana At1g68290 gene is a glycoprotein that digests RNA, ssDNA, and dsDNA. AtBFN2 depends on three zinc ions for cleaving DNA and RNA at 3′-OH to yield 5′-nucleotides. In addition, AtBFN2′s enzymatic activity is strongly glycan dependent. Plant Zn2+-dependent endonucleases present a unique fold, and belong to the Phospholipase C (PLC)/P1 nuclease superfamily. In this work, we present the first complete, ligand-free, AtBFN2 crystal structure, along with sulfate, phosphate and ssDNA co-crystal structures. With these, we were able to provide better insight into the glycan structure and possible enzymatic mechanism. In comparison with other nucleases, the AtBFN2/ligand-free and AtBFN2/PO4 models suggest a similar, previously proposed, catalytic mechanism. Our data also confirm that the phosphate and vanadate can inhibit the enzyme activity by occupying the active site. More importantly, the AtBFN2/A5T structure reveals a novel and conserved secondary binding site, which seems to be important for plant Zn2+-dependent endonucleases. Based on these findings, we propose a rational ssDNA binding model, in which the ssDNA wraps itself around the protein and the attached surface glycan, in turn, reinforces the binding complex. [ABSTRACT FROM AUTHOR]

Background: This randomized, double-blind, parallel-group clinical trial aims to assess the equivalence of intra-articular polynucleotides compared to standard hyaluronic acid (HA) viscosupplementation in the treatment of knee osteoarthritis (OA). Methods: 75 patients affected by knee OA were assessed for eligibility and 72 were enrolled and randomized to receive either intra-articular polynucleotides (Condrotide-36 patients) or hyaluronic acid (Hyalubrix-36 patients) at the Orthopedic Institute "Gaetano Pini" (Milan). All patients underwent three intra-articular injections of Condrotide or Hyalubrix with an interval of 1 week. Participants, care givers, and investigators responsible for outcome assessment were all blinded to group assignment. Primary outcome measurements (KOOS and pain level (1)atrest, (2)at weight-bearing and (3) during physical activity) were evaluated at baseline (T0) and after one (T1), two (T2), six (T6), ten (T10), and 26 (T26) weeks. Secondary measurements included the determination of COMP serum levels at T0, T6 and T26. Results: The reduction of pain and the increase of KOOS values from baseline were statistically significant for both treatments; nevertheless, for parameter KOOS "symptoms" the treatment with Condrotide showed significant results already after two weeks (at T2 p = 0.003) while the results obtained with Hyalubrix became significant only after 18 weeks (at T18 p = 0.01). No significant adverse events were reported. Conclusions: Condrotide is as effective as Hyalubrix in reducing knee OA symptoms but showed an earlier response on pain reduction and can therefore be considered a valid alternative to the use of HA in the treatment of OA, avoiding the adverse events of NSAIDs and of intra-articular corticosteroids. [ABSTRACT FROM AUTHOR]

We conducted a randomized, double-blind clinical trial to assess the efficacy of intra-articular injections of polynucleotides versus hyaluronan in patients with symptomatic knee osteoarthritis. The 30 patients enrolled were randomized in two groups and received 3 intra-articular knee injections at 1 week intervals with either polynucleotides (Condrotide™, n=15) or hyaluronan (Synocrom®, n=15). The patients were followed for 3 months after the end of treatment, with clinical evaluation before administering the first injection and then at 4, 8 and 16 weeks afterward. We used the Visual Analog Scale for pain assessment and calculated the Knee Osteoarthritis Outcome Score and Knee Society Scores (knee and functional). We found a statistically significant decrease of pain levels in both groups, with Knee Society Scores showing a statistically significant improvement only in the polynucleotide group. We concluded that the use of polynucleotide injections in the treatment of knee arthritis is a viable option in symptomatic cases. [ABSTRACT FROM AUTHOR]

We conducted a randomized, double-blind clinical trial to assess the efficacy of intra-articular injections of polynucleotides versus hyaluronan in patients with symptomatic knee osteoarthritis. The 30 patients enrolled were randomized in two groups and received 3 intra-articular knee injections at 1 week intervals with either polynucleotides (Condrotide™, n=15) or hyaluronan (Synocrom®, n=15). The patients were followed for 3 months after the end of treatment, with clinical evaluation before administering the first injection and then at 4, 8 and 16 weeks afterward. We used the Visual Analog Scale for pain assessment and calculated the Knee Osteoarthritis Outcome Score and Knee Society Scores (knee and functional). We found a statistically significant decrease of pain levels in both groups, with Knee Society Scores showing a statistically significant improvement only in the polynucleotide group. We concluded that the use of polynucleotide injections in the treatment of knee arthritis is a viable option in symptomatic cases. [ABSTRACT FROM AUTHOR]

Aim Adenosine receptors modulate inflammation in periodontal tissues. No data are available regarding the effects of adenosine A2A receptor stimulation in experimental periodontitis ( EPD). The aim of this study was to investigate the effects of polynucleotides (also known as polydeoxyribonucleotide, PDRN), a ligand of A2A receptor, in EPD in rats. Materials and Methods EPD was induced ligating the cervix of the lower left first molar. Sham- EPD had no ligature. After 7 days, EPD animals were randomized to a daily treatment with vehicle gel or 0.75% PDRN gel or PDRN gel with a specific A2A antagonist ( DMPX). Treatments lasted 7 days. Animals were then euthanized and the periodontium and surrounding gingival tissue were excised for histological evaluation and bio-molecular analysis of inflammatory (p- JNK, p- ERK, TNF-α, IL-6, HMGB-1) and apoptotic proteins ( BAX and Bcl-2). Results Vehicle-treated EPD rats showed severe inflammatory infiltrate in both gingival and periodontal ligament, as well as an enhanced expression of p- JNK, p- ERK, TNF-α, IL-6, HMGB-1 and BAX and a reduction in Bcl-2. PDRN gel restored the histological features, blunted inflammatory and apoptotic proteins expression and preserved Bcl-2 expression. DMPX abrogated PDRN positive effects. Conclusion Our data suggest that adenosine receptor stimulation by PDRN might represent a new therapeutic strategy for periodontitis. [ABSTRACT FROM AUTHOR]

Abstract: Binding of the phenothaizinium dye thionine with four sequence specific deoxyribopolynucleotides, poly(dG-dC).poly(dG-dC), poly(dG).poly(dC), poly(dA-dT).poly(dA-dT), and poly(dA).poly(dT) has been investigated by means of thermal helix melting, isothermal titration calorimetry, and differential scanning calorimetry experiments. The binding affinity values evaluated from isothermal titration calorimetry suggests that thionine exhibits the highest binding affinity to poly(dG-dC).poly(dG-dC). The binding to poly(dG-dC).poly(dG-dC), poly(dA-dT).poly(dA-dT), and poly(dG).poly(dC) is exothermic and favoured by negative enthalpy changes while binding to poly(dA).poly(dT) is endothermic and anomalous. The values of heat capacity changes of the interaction are negative and in the range (−0.4 to −0.5)kJ·K−1 ·mol−1. The binding is characterized by strong stabilization of the polynucleotides against thermal strand separation. The binding affinity values derived from thermal melting data are in excellent agreement with those obtained from isothermal titration calorimetry data. Insights into the energetic aspects and guanine–cytosine selectivity of the DNA interaction of thionine have been obtained from these studies. [Copyright &y& Elsevier]

Abstract: In this work unilamellar liposomes doped with a novel non-ionic 5′-Uridine-head nucleolipid, Lauroyl Uridine (LU), were prepared and characterized for their ability to interact with the polynucleotide polyadenylic acid (poly-A). Vesicles, were made up of the cationic lipid DOTAP (1,2-Dioleoyl-3-Trimethylammonium-Propane), the zwitterionic lipid DOPE (1,2-Dioleoyl-sn-Glycero-3-Phosphoethanolamine), and the novel amphiphile Lauroyl Uridine. The influence of the non-ionic nucleolipid on essential liposomes properties, such as the structure and net charge was first investigated by a comparative analysis performed on the different lipoplex preparations by means of ζ-potential and size measurements. Both structure and net charge of liposomes were shown to be not modified by the presence of the non-ionic nucleolipid. The role of the synthetic lipid inserted as anchor in the liposome bilayer in the condensation process between vesicles and the polynucleotide poly-A was then analyzed by UV–vis, Circular Dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopies. The data presented comparative UV–vis analyses that evidenced the occurrence of staking interactions in the poly-A only in LU containing lipoplexes. CD and NMR studies indicated the presence of H-bonding interaction between Lauroyl Uridine containing vesicles and the polynucleotide poly-A. The results presented in this work support a role for Lauroyl Uridine in A-U molecular recognition, thus, suggesting that cationic liposomes doped with the non-ionic nucleolipid Lauroyl Uridine could represent a model system to study molecular interactions among single stranded polynucleotides and lipid anchor bearing the complementary bases. [ABSTRACT FROM AUTHOR]

Abstract: The study of genetic sequences is of great importance in biology and medicine. Sequence analysis and taxonomy are two major fields of application of bioinformatics. In the present paper we extend the notion of entropy and clarity to the use of different metrics and apply them in the case of the Fuzzy Polynuclotide Space (FPS). Applications of these notions on selected polynucleotides and complete genomes both in the I 12×k space, but also using their representation in FPS are presented. Our results show that the values of fuzzy entropy/clarity are indicative of the degree of complexity necessary for the description of the polynucleotides in the FPS, although in the latter case the interpretation is slightly different than in the case of the I 12×k hypercube. Fuzzy entropy/clarity along with the use of appropriate metrics can contribute to sequence analysis and taxonomy. [ABSTRACT FROM AUTHOR]

Abstract: Energetics of the binding of two known classical DNA intercalating molecules, ethidium and sanguinarine with four sequence specific polynucleotides, poly(dG-dC).poly(dG-dC), poly(dG).poly(dC), poly(dA-dT).poly(dA-dT), and poly(dA).poly(dT) have been compared under identical conditions. The binding of both the molecules was characterized by strong stabilization of the polynucleotides against thermal strand separation in optical melting as well as differential scanning calorimetry studies. Isothermal titration calorimetry results revealed that the binding of both sanguinarine and ethidium to poly(dG-dC).poly(dG-dC), poly(dA-dT).poly(dA-dT), and poly(dG).poly(dC) was exothermic and favoured by negative enthalpy changes. On the other hand, the binding of both molecules to poly(dA).poly(dT) was endothermic and entropy driven. The binding affinity values obtained from isothermal titration calorimetry data was in close proximity to that derived from thermal melting data. The heat capacity changes obtained from temperature dependence of the enthalpy change gave negative values in the range (−0.4 to 1.25)kJ·mol−1 ·K−1 for the binding of ethidium and sanguinarine to these polynucleotides. The variations in the values indicate important differences in the formation of the complexes. New insights into the energetics and specificity aspects of interaction of these molecules to DNA have emerged from these studies. [Copyright &y& Elsevier]

Abstract: We provide a brief overview of the structural characteristics of the main groups of conjugated polyelectrolytes (CPEs) as well as the methods of synthesis and their behaviour in solution. Their tendency to form aggregates in solution, which is one of the key points to be taken into account for them to be used in polynucleotide sensing, is also considered and the various strategies adopted to avoid it will be discussed. These include the synthetic one (with the incorporation of charged and/or bulky substituents), the use of organic co-solvents and the addition of surfactants. The main physical chemical changes (optical, photophysical, electrical conductivity and viscosity) observed upon direct binding between polynucleotide and CPE, the kind of interactions involved and their applicability in sensing are considered as a function of the CPE structural rigidity. Moreover, more complex devices developed in CPE–polynucleotide sensing with the involvement of additional spectroscopic probes to induce Förster resonant energy transfer processes (FRET) or superquenching phenomena are reviewed. Finally, the main CPE applications in biosensing and the potential use of these systems in understanding DNA compaction and possible extension to the construction of supramolecular oligonucleotide structures are summarized. [Copyright &y& Elsevier]

This randomized, double-blind clinical trial was conducted over 16 weeks to assess the efficacy and safety profile of intra-articular polynucleotides gel injections in the treatment of knee osteoarthritis associated with persistent knee pain. 60 patients were enrolled and randomized to receive intra-articular polynucleotides ( n = 30) or hyaluronan ( n = 30); patients received five weekly intra-articular knee injections and the follow-up period was 3 months after the end of treatment. Primary endpoint was to determine polynucleotides (PN) efficacy in reducing knee pain at the end of the study, over baseline value and over standard hyaluronan viscosupplementation (HA). Pain levels were measured using a 0–10 cm Visual Analogue Scale (VAS). Secondary endpoints included Knee Osteoarthritis Outcome Score (KOOS), NSAIDs consumption, crackling during movement and articular mobility limitation. The mean global VAS pain decreased from 5.7 ± 1.9 cm (T0) to 1.9 ± 1.5 cm (T16) in polynucleotide group and from 4.9 ± 2.0 cm (T0) to 2.1 ± 1.4 cm (T16) in hyaluronan group. The reduction in pain was statistically significant for both groups. KOOS increases from baseline values were statistically significant in both groups. No significant adverse events were reported. These findings suggest that intra-articular polynucleotides can be a valid alternative to traditional hyaluronan supplementation for the treatment of knee osteoarthritis. [ABSTRACT FROM AUTHOR]

Summary: Objective: A theory of fuzzy polynucleotides, including an n-dimensional metric fuzzy polynucleotide space, has been previously introduced by the present author for fuzzy-theoretical analysis of nucleic acids [Sadegh-Zadeh K. Fuzzy genomes. Artif Intell Med 2000;18:1–28; Sadegh-Zadeh K. Ein Verfahren zur Fuzzydecodierung und Fuzzydechiffrierung von Informationen. Offenlegungsschrift DE 199 36 925 A 1. Deutsches Patent- und Markenamt; 2001]. The conceptual framework of that theory has been used by Nieto et al. [Nieto JJ, Torres A, Vázquez-Trasande MM. A metric space to study differences between polynucleotides. Appl Math Lett 2003;16:1289–94; Nieto JJ, Torres A, Georgiou DN, Karakasidis TE. Fuzzy polynucleotide spaces and metrics. Bull Math Biol 2006;68:703–25] and Torres et al. [Torres A, Nieto JJ. The fuzzy polynucleotide space: basic properties. Bioinformatics 2003;19:587–92; Torres A, Nieto JJ. Fuzzy logic in medicine and bioinformatics. J Biomed Biotechnol 2006;1–7 [Article ID 91908]] to create a completely different, 12-dimensional metric space which they have also called ‘the fuzzy polynucleotide space’. In the present paper both spaces are compared. Material and method: Both metric spaces are briefly outlined. Similarity and dissimilarity relationships between polynucleotide strings are measured in both spaces to compare their performance. Results: Nieto et al.''s and Torres et al.''s metric space measures the relationships between polynucleotide chains incorrectly. Structurally highly different polynucleotide sequences are misclassified as highly similar ones, and completely different sequences are misclassified as identical ones. For this reason their construct is to be considered as a device of misdiagnosis that bears “fuzzy polynucleotide space” as a misnomer. [Copyright &y& Elsevier]

Abstract: The base dependent binding of the cytotoxic alkaloid palmatine to four synthetic polynucleotides, poly(dA).poly(dT), poly(dA–dT).poly(dA–dT), poly(dG).poly(dC) and poly(dG–dC).poly(dG–dC) was examined by competition dialysis, spectrophotometric, spectrofluorimetric, thermal melting, circular dichroic, viscometric and isothermal titration calorimetric (ITC) studies. Binding of the alkaloid to various polynucleotides was dependent upon sequences of base pairs. Binding data obtained from absorbance measurements according to neighbour exclusion model indicated that the intrinsic binding constants decreased in the order poly(dA).poly(dT)>poly(dA–dT).poly(dA–dT)>poly(dG–dC).poly(dG–dC)>poly(dG).poly(dC). This affinity was also revealed by the competition dialysis, increase of steady state fluorescence intensity, increase in fluorescence quantum yield, stabilization against thermal denaturation and perturbations in circular dichroic spectrum. Among the polynucleotides, poly(dA).poly(dT) showed positive cooperativity at binding values lower than r =0.05. Viscosity studies revealed that in the strong binding region, the increase of contour length of DNA depended strongly on the sequence of base pairs being higher for AT polymers and induction of unwinding–rewinding process of covalently closed superhelical DNA. Isothermal titration calorimetric data showed a single entropy driven binding event in the AT homo polymer while that with the hetero polymer involved two binding modes, an entropy driven strong binding followed by an enthalpy driven weak binding. These results unequivocally established that the alkaloid palmatine binds strongly to AT homo and hetero polymers by mechanism of intercalation. [Copyright &y& Elsevier]

Abstract: Novel bis-nucleobase–phenanthridinium conjugates were synthesised and their aqueous solutions spectroscopically characterised. Bis-adenine conjugate revealed in aqueous solutions significantly more pronounced intramolecular aromatic stacking interactions than bis-uracil analogue. In contrast with previously reported poly A recognition by bis-uracil conjugate, recognition of complementary nucleotides and poly U was not observed due to the strong interference of bulk water with hydrogen bonding between nucleobases. The screening of anticancer activity on six human cell lines revealed that tethering of a nucleobase to phenanthridinium moiety diminished antiproliferative potential of phenanthridinium. However, among mono-nucleobase conjugates adenine derivative was found to be the most selective one (MiaPaCa–2, Hep–2). [Copyright &y& Elsevier]

Abstract: The electroporative transfer of gene DNA and other bioactive substances into tissue cells by electric pulses gains increasing importance in the new disciplines of electrochemotherapy and electrogenetherapy. The efficiency of the electrotransfer depends crucially on the adsorption of the gene DNA and oligonucleotides to the plasma cell membranes. Here it is shown that the adsorption of larger oligonucleotides such as fragments (ca. 300 bp) of sonicated calf-thymus DNA, to anionic lipids of unilamellar vesicles (diameter Φ =300±90 nm) is greatly enhanced by divalent cations such as Ca2+-ions. Applying centrifugation, bound and free DNA are monitored optically at the wavelength λ =260 nm. Using arsenazo III as a Ca2+-indicator and atomic absorption spectroscopy (AAS), Ca2+-titrations of DNA and vesicles yield the individual equilibrium constants of Ca2+- and DNA-binding not only for the binary complexes: Ca/lipids, Ca/DNA and DNA/lipids, respectively, but also for the various processes to form the ternary complex DNA/Ca/lipids. The data provide the basis for goal-directed optimization protocols for the adsorption and thus efficient electrotransfer of oligonucleotides and polynucleotides into cells. [Copyright &y& Elsevier]

The study of genetic sequences is of great importance in biology and medicine. Mathematics is playing an important role in the study of genetic sequences and, generally, in bioinformatics. In this paper, we extend the work concerning the Fuzzy Polynuclotide Space (FPS) introduced in Torres, A., Nieto, J.J., 2003. The fuzzy polynuclotide Space: Basic properties. Bioinformatics 19(5); 587-592 and Nieto, J.J., Torres, A., Vazquez-Trasande, M.M. 2003. A metric space to study differences between polynucleotides. Appl. Math. Lett. 27:1289-1294: by studying distances between nucleotides and some complete genomes using several metrics. We also present new results concerning the notions of similarity, difference and equality between polynucleotides. The results are encouraging since they demonstrate how the notions of distance and similarity between polynucleotides in the FPS can be employed in the analysis of genetic material. [ABSTRACT FROM AUTHOR]

Describes a life of studying crystallography. Educational background; Base interactions for some polynucleotides; Developments at the National Institutes of Health; Information on the tunnels and channeling of tryptophan synthase.

Abstract: Schizophyllan belongs to the β-(1 → 3)-d-glucan family and is well known as a triple helix polysaccharide. It is already known that the single chain of schizophyllan (s-SPG) can specifically form a complex with particular polynucleotides. As an application of this recognition capability, a novel schizophyllan derivative connected with a disulfide bond through a long methylene spacer was synthesized, and its interaction with polynucleotides was directly monitored with a self-assembled monolayer on QCM. The gold-coated QCM electrode was covered in ca. 60% as a monolayer of s-SPG. The QCM resonator showed sensitive mass increases for poly(C) and poly(U) in the presence of K+ ion, which are consistent with our previous results. The present results indicate that the schizophyllan-immobilized QCM resonator can be a new sensing device for biomolecules. [Copyright &y& Elsevier]

Differential UV spectroscopy and thermal denaturation were used to study the Mg2+ ion effect on the conformational equilibrium in poly A · 2 poly U (A2U) and poly A · poly U (AU) solutions at low (0.01 M Na+) and high (0.1 M Na+) ionic strengths. Four complete phase diagrams were obtained for Mg2+–polynucleotide complexes in ranges of temperatures 20–96 °C and concentrations (10−5–10−2) M Mg2+. Three of them have a ‘critical’ point at which the type of the conformational transition changes. The value of the ‘critical’ concentration ([Mgt2+]cr=(4.5±1.0)×10−5 M) is nearly independent of the initial conformation of polynucleotides (AU, A2U) and of Na+ contents in the solution. Such a value is observed for Ni2+ ions too. The phase diagram of the (A2U+Mg2+) complex with 0.01 M Na+ has no ‘critical’ point: temperatures of (3→2) and (2→1) transitions increase in the whole Mg2+ range. In (AU+Mg2+) phase diagram at 0.01 M Na+ the temperature interval in which triple helices are formed and destroyed is several times larger than at 0.1 M Na+. Using the ligand theory, a qualitative thermodynamic analysis of the phase diagrams was performed. [Copyright &y& Elsevier]

A new family of nanoscale materials on the basis of dispersed networks of cross-linked ionic and nonionic hydrophilic polymers is being developed. One example is the nanosized cationic network of cross-linked poly(ethylene oxide) (PEO) and polyethyleneimine (PEI), PEO-cl-PEI nanogel. Interaction of anionic amphiphilic molecules or oligonucleotides with PEO-cl-PEI results in formation of nanocomposite materials in which the hydrophobic regions from polyion-complexes are joined by the hydrophilic PEO chains. Formation of polyion-complexes leads to the collapse of the dispersed gel particles. However, the complexes form stable aqueous dispersions due to the stabilizing effect of the PEO chain. These systems allow for immobilization of negatively charged biologically active compounds such as retinoic acid, indomethacin and oligonucleotides (bound to polycation chains) or hydrophobic molecules (incorporated into nonpolar regions of polyion–surfactant complexes). The nanogel particles carrying biological active compounds have been modified with polypeptide ligands to enhance receptor-mediated delivery. Efficient cellular uptake and intracellular release of oligonucleotides immobilized in PEO-cl-PEI nanogel have been demonstrated. Antisense activity of an oligonucleotide in a cell model was elevated as a result of formulation of oligonucleotide with the nanogel. This delivery system has a potential of enhancing oral and brain bioavailability of oligonucleotides as demonstrated using polarized epithelial and brain microvessel endothelial cell monolayers. [Copyright &y& Elsevier]

Hydrogen peroxide in the presence of short wavelength UV light was able to induce alterations in native DNA fragments of 300 bp (ROS-ONA), thereby rendering it immunogenic in experimental animals. The specificity of induced antibodies was investigated by direct binding and competition ELISA. Inhibition studies revealed nearly 89% inhibition in the antibody binding by the immunogen and recognition of native B-. A- and allied conformations presented by various synthetic polynucleotides. Gel retardation assay reiterated the formation of immune complexes between induced antibodies and native and ROS-DNA fragments. It was observed that naturally occurring anti-DNA autoantibodies from systemic lupus erythematosus (SLE) sera recognize ROS-DNA. The comparison of the specificities of anti-DNA autoantibodies from 10 SLE patients showed a 20-50- fold preference for ROS-DNA over native DNA. These results demonstrate that anti-DNA antibodies can be induced by ROS-DNA, and that some of the autoimmune DNA binding antibodies found in SLE may result from response to reactive oxygen species. [ABSTRACT FROM AUTHOR]

Immunochemical properties of monoclonal autoantibodies lo single stranded DNA (ssDNA), which were derived from systemic lupus erythematosus (SLE) prone mice and were specific for poly(dG), were studied using a hapten inhibition assay with oligo- and mononucleotides. Deoxyguanosine monophosphate (dGMP) completely inhibited the ssDNA binding of poly(dG) specific monoclonal antibodies. The affinity to deoxyguanosine was approximately 70% of dGMP, and to guanosine monophosphate (GMP) and to guanosine was 38% and 24% respectively. In contrast, other purine monomers such as deoxyadenosine monophosphate (dAMP), adenosine monophosphate (AMP) and adenosine exhibited virtually no inhibitory effect on the ssDNA binding of these monoclonal hybridoma autoantibodies. By the same competitive inhibition enzyme immunoassay using deoxyguanosine oligonucleotides of various chain lengths, the minimal antigenic size of ssDNA encompassed by the combining site of the Fab portion of anti-ssDNA monoclonal autoantibodies was determiend to be the tetra- or pentanucleotide. [ABSTRACT FROM AUTHOR]