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1.
BMC Musculoskelet Disord ; 22(1): 773, 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34511091

RESUMO

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.


Assuntos
Ácido Hialurônico , Osteoartrite do Joelho , Seguimentos , Humanos , Osteoartrite do Joelho/tratamento farmacológico , Polinucleotídeos , Resultado do Tratamento
3.
Appl Environ Microbiol ; 87(18): e0054321, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34232745

RESUMO

In Serratia marcescens JNB5-1, prodigiosin was highly produced at 30°C, but it was noticeably repressed at ≥37°C. Our initial results demonstrated that both the production and the stability of the O-methyl transferase (PigF) and oxidoreductase (PigN) involved in the prodigiosin pathway in S. marcescens JNB5-1 sharply decreased at ≥37°C. Therefore, in this study, we improved mRNA stability and protein production using de novo polynucleotide fragments (PNFs) and the introduction of disulfide bonds, respectively, and observed their effects on prodigiosin production. Our results demonstrate that adding PNFs at the 3' untranslated regions of pigF and pigN significantly improved the mRNA half-lives of these genes, leading to an increase in the transcript and expression levels. Subsequently, the introduction of disulfide bonds in pigF improved the thermal stability, pH stability, and copper ion resistance of PigF. Finally, shake flask fermentation showed that the prodigiosin titer with the engineered S. marcescens was increased by 61.38% from 5.36 to 8.65 g/liter compared to the JNB5-1 strain at 30°C and, significantly, the prodigiosin yield increased 2.05-fold from 0.38 to 0.78 g/liter at 37°C. In this study, we revealed that the introduction of PNFs and disulfide bonds greatly improved the expression and stability of pigF and pigN, hence efficiently enhancing prodigiosin production with S. marcescens at 30 and 37°C. IMPORTANCE This study highlights a promising strategy to improve mRNA/enzyme stability and to increase production using de novo PNF libraries and the introduction of disulfide bonds into the protein. PNFs could increase the half-life of target gene mRNA and effectively prevent its degradation. Moreover, PNFs could increase the relative intensity of target genes without affecting the expression of other genes; as a result, it could alleviate the cellular burden compared to other regulatory elements such as promoters. In addition, we obtained a PigF variant with improved activity and stability by the introduction of disulfide bonds into PigF. Collectively, we demonstrate here a novel approach for improving mRNA/enzyme stability using PNFs, which results in enhanced prodigiosin production in S. marcescens at 30°C.


Assuntos
Proteínas de Bactérias/genética , Metiltransferases/genética , Prodigiosina/biossíntese , Serratia marcescens/genética , Serratia marcescens/metabolismo , Regiões 3' não Traduzidas , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Dissulfetos/química , Fermentação , Concentração de Íons de Hidrogênio , Metiltransferases/química , Metiltransferases/metabolismo , Simulação de Dinâmica Molecular , Polinucleotídeos/genética , Estabilidade Proteica , RNA Mensageiro/genética , Temperatura
4.
Angew Chem Int Ed Engl ; 60(43): 23241-23247, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34302317

RESUMO

Combining surface-initiated, TdT (terminal deoxynucleotidyl transferase) catalyzed enzymatic polymerization (SI-TcEP) with precisely engineered DNA origami nanostructures (DONs) presents an innovative pathway for the generation of stable, polynucleotide brush-functionalized DNA nanostructures. We demonstrate that SI-TcEP can site-specifically pattern DONs with brushes containing both natural and non-natural nucleotides. The brush functionalization can be precisely controlled in terms of the location of initiation sites on the origami core and the brush height and composition. Coarse-grained simulations predict the conformation of the brush-functionalized DONs that agree well with the experimentally observed morphologies. We find that polynucleotide brush-functionalization increases the nuclease resistance of DONs significantly, and that this stability can be spatially programmed through the site-specific growth of polynucleotide brushes. The ability to site-specifically decorate DONs with brushes of natural and non-natural nucleotides provides access to a large range of functionalized DON architectures that would allow for further supramolecular assembly, and for potential applications in smart nanoscale delivery systems.


Assuntos
DNA/química , Nanoestruturas/química , Polinucleotídeos/química , DNA Nucleotidilexotransferase/química , Nucleotídeos de Desoxiuracil/química , Conformação de Ácido Nucleico , Polimerização , Estudo de Prova de Conceito , Nucleotídeos de Timina/química
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 260: 119914, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34015745

RESUMO

We present here a combined spectroscopic and theoretical analysis of the binding of N,N'-bis(2-(1-piperazino)ethyl)-3,4,9,10-perylenetetracarboxylic acid diimide dichloride (PZPERY) to different biosubstrates. Absorbance titrations and circular dichroism experiments, melting studies and isothermal calorimetry (ITC) titrations reveal a picture where the binding to natural double-stranded DNA is very different from that to double and triple-stranded RNAs (poly(A)∙poly(U) and poly(U)∙poly(A)⁎poly(U)). As confirmed also by the structural and energetic details clarified by density functional theory (DFT) calculations, intercalation occurs for DNA, with a process driven by the combination of aggregates disruption and monomers intercalation. Oppositely, for RNAs, no intercalation but groove binding with the formation of supramolecular aggregates is observed. Among all the tested biosubstrates, the affinity of PZPERY towards DNA G-quadruplexes (G4) is the greatest one with a preference for human telomeric G4s. Focusing on hybrid G4 forms, either sitting-atop ("tetrad-parallel") or lateral ("groove-parallel") binding modes were considered in the discussion of the experimental results and molecular dynamics (MD) simulations. Both turned out to be possible concurrently, in agreement also with the experimental binding stoichiometries higher than 2:1.


Assuntos
Quadruplex G , Perileno , Dicroísmo Circular , DNA , Humanos , Polinucleotídeos , RNA , Água
7.
Aesthetic Plast Surg ; 45(4): 1792-1801, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33876290

RESUMO

BACKGROUND: Poly-L-lactic acid (PLLA) is widely used in tissue engineering. The natural polymer hyaluronic acid (HA) shows excellent biocompatibility and affects cell signaling, proliferation, and differentiation. In addition, a polynucleotide (PN) induces cell growth of human skin fibroblasts and osteoblasts. OBJECTIVE: In this study, we evaluated the properties, safety, and efficacy of a novel composite filler consisting of cross-linked HA with PN in combination with monodisperse PLLA microspheres manufactured using Inventage Lab Precision Particle Fabrication method. MATERIALS AND METHODS: The composition of the filler and characteristics of the microspheres were examined via scanning electron microscopy, particle size analysis, gel permeation chromatography, and rheology and osmolality measurement. Additionally, safety and efficacy of HA-PN/PLLA composite filler were conducted in in vitro and in vivo. RESULTS: Analysis of PLLA microspheres revealed spherical surfaces and a narrower particle size distribution than that in PLLA filler. HA-PN/PLLA composite filler had higher viscosity and elasticity values and similar osmolality as compared to those of HA and PN fillers. The nontoxicity in in vitro and in vivo tests reflected that the composite filler may be safe for human use. In addition, the composite filler maintained a more stable volume than did HA filler for 24 weeks after administration in HWY/Slc hairless rats. Furthermore, the results support the effect of HA-PN/PLLA in restoring skin structure. CONCLUSION: Altogether, these data suggest that the novel composite filler might be a safe and effective option in terms of tissue integration, clinical management during delivery and high esthetic durability. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Técnicas Cosméticas , Preenchedores Dérmicos , Ácido Hialurônico , Poliésteres , Polinucleotídeos
8.
Aesthet Surg J ; 41(7): NP866-NP874, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-33755110

RESUMO

BACKGROUND: Managing acne scars is a challenge and therapies are divided into nonsurgical and surgical. Highly Purified Technology Polynucleotides (PN-HPT) is a compound that contains a mixture of DNA polymers of different lengths. Numerous studies have shown that PN-HPT also serves as an energy source, thus influencing cellular growth and cell vitality. OBJECTIVES: The authors aimed to assess the improvement in dermal quality and acne scars after PN-HPT vs placebo according to Antera 3D and the patient responses to the patient satisfaction questionnaire after a comparison of pretreatment and posttreatment photographs at 1 and 3 months. METHODS: Included were women aged 30 to 50 years with grade 3 to 4 moderate-to-severe atrophic scars according to the Goodman classification; nonsmokers; and had not had active acne during the past 5 years. Ten patients (PN-HPT group) were treated with 4.0 mL of PN-HPT, and 10 patients (control) were treated with 4.0 mL of normal saline. All medical treatments were performed in a double-blinded manner; neither the injection doctor nor the patient knew if the PN-HPT or the placebo was being administered. RESULTS: Twenty women who fit the inclusion criteria were enrolled in this study. Only patients in the PN-HPT group improved significantly at 1 and 3 months after treatment compared with baseline. CONCLUSIONS: This prospective and randomized study showed that PN-HPT in monotherapy was safe and effective treatment for atrophic scar acne compared with placebo. Prospective and randomized studies will be necessary to investigate the clinical effectiveness in a larger cohort of patients and for a longer follow-up.


Assuntos
Acne Vulgar , Cicatriz , Acne Vulgar/complicações , Acne Vulgar/tratamento farmacológico , Atrofia , Cicatriz/tratamento farmacológico , Cicatriz/etiologia , Feminino , Humanos , Polinucleotídeos , Estudos Prospectivos , Resultado do Tratamento
9.
Eur Phys J E Soft Matter ; 44(2): 24, 2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33686498

RESUMO

Hybrids formed by DNA/RNA and graphene family nanomaterials are considered as potentially useful multifunctional agents in biosensing and nanomedicine. In this work, we study the noncovalent interaction between double-stranded (ds) RNA, polyadenylic:polyuridylic acids (poly(A:U)) and graphene oxide/graphene (GO/Gr) using UV absorption spectroscopy and molecular dynamics (MD) simulations. RNA melting showed that relatively long ds-RNA is adsorbed onto GO (at an ionic strength of [Formula: see text]) at that a large fraction of RNA maintains the duplex structure. It was revealed that this fraction decreases over long time (during a few days), indicating a slow adsorption process of the long polymer. MD simulations showed that the adsorption of duplex (rA)[Formula: see text]: (rU)[Formula: see text] or (rA)[Formula: see text]: (rU)[Formula: see text] on graphene starts with the interaction between [Formula: see text]-systems of graphene and base pairs located at a duplex tail. In contrast to relatively long duplex (rA)[Formula: see text]: (rU)[Formula: see text] which keeps parallel arrangement along the graphene surface, the shorter one ((rA)[Formula: see text]: (rU)[Formula: see text]) always adopts a perpendicular orientation relative to graphene even in case of the initial parallel orientation. It was found out that (rA)[Formula: see text]: (rU)[Formula: see text] forms the stable hybrid with graphene keeping essential fraction of the duplex, while (rA)[Formula: see text]: (rU)[Formula: see text] demonstrates the duplex unzipping into two single strands with time. The interaction energies between adenine/uracil stacked with graphene as well between nucleotides in water environment were determined.


Assuntos
Grafite/química , Nanoestruturas/química , Poli A/química , Polinucleotídeos/química , RNA de Cadeia Dupla/química , Adsorção , Simulação de Dinâmica Molecular , Concentração Osmolar , Poli U/química , Propriedades de Superfície
11.
J Cosmet Dermatol ; 20(3): 922-928, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32799391

RESUMO

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.


Assuntos
Técnicas Cosméticas , Envelhecimento da Pele , Consenso , Estética , Humanos , Ácido Hialurônico , Polinucleotídeos , Rejuvenescimento , Tecnologia
12.
Appl Environ Microbiol ; 87(3)2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33188001

RESUMO

Much of virus fate, both in the environment and in physical/chemical treatment, is dependent on electrostatic interactions. Developing an accurate means of predicting virion isoelectric point (pI) would help to understand and anticipate virus fate and transport, especially for viruses that are not readily propagated in the lab. One simple approach to predicting pI estimates the pH at which the sum of charges from ionizable amino acids in capsid proteins approaches zero. However, predicted pIs based on capsid charges frequently deviate by several pH units from empirically measured pIs. Recently, the discrepancy between empirical and predicted pI was attributed to the electrostatic neutralization of predictable polynucleotide-binding regions (PBRs) of the capsid interior. In this paper, we review models presupposing (i) the influence of the viral polynucleotide on surface charge or (ii) the contribution of only exterior residues to surface charge. We then compare these models to the approach of excluding only PBRs and hypothesize a conceptual electrostatic model that aligns with this approach. The PBR exclusion method outperformed methods based on three-dimensional (3D) structure and accounted for major discrepancies in predicted pIs without adversely affecting pI prediction for a diverse range of viruses. In addition, the PBR exclusion method was determined to be the best available method for predicting virus pI, since (i) PBRs are predicted independently of the impact on pI, (ii) PBR prediction relies on proteome sequences rather than detailed structural models, and (iii) PBR exclusion was successfully demonstrated on a diverse set of viruses. These models apply to nonenveloped viruses only. A similar model for enveloped viruses is complicated by a lack of data on enveloped virus pI, as well as uncertainties regarding the influence of the phospholipid envelope on charge and ion gradients.


Assuntos
Modelos Biológicos , Polinucleotídeos , Vírus , Ponto Isoelétrico , Eletricidade Estática
13.
Talanta ; 224: 121899, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33379105

RESUMO

MicroRNAs (miRNAs) are associated with various cellular processes and have been recognized as potential biomarkers for many human diseases. The sensitive and accurate determination of miRNA expression levels in biological specimens is highly significant for understanding their biological functions and clinical diagnosis. Mass spectrometry (MS) has shown its potential to study bioactive molecules, however, direct MS analysis of miRNAs is often hampered by limited sensitivity. For sensitive detection of miRNAs, indirect methods are generally employed through the use of DNA probes labeled with peptides or metal elements. In this work, we proposed a novel MS-based label-free strategy for miRNA quantification. A dual-amplification system was developed by using a padlock probe containing the poly(thymine) sequence in combination with rolling circle amplification (RCA). The specific recognition of target miRNA by the padlock probes produced long single-stranded DNAs containing poly (adenine) segments, which guaranteed the specificity of detection and realized primary amplification. Then the RCA products were extracted and treated with acid to release a large number of free adenines as reporter molecules for secondary signal amplification. Overall, the quantification of target miRNA was carried out by signal switching from high-molecular-weight RCA products to highly sensitive small molecule of adenine. The developed method achieved a linear detection range from 200 amol to 100 fmol for miRNA-21 with a limit of detection of 50 amol, and successfully applied to detect endogenous miRNA-21 levels from lung cancer cells. Overall, the present study provides a sensitive, specific MS-based method for miRNA detection and holds great potential for further application of MS technology to detect other biomarkers in biomedical research and early clinical diagnosis.


Assuntos
MicroRNAs , Humanos , Limite de Detecção , Espectrometria de Massas , MicroRNAs/genética , Técnicas de Amplificação de Ácido Nucleico , Polinucleotídeos
14.
Syst Appl Microbiol ; 44(1): 126173, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33352459

RESUMO

Recent developments in fluorescence in situ hybridization (FISH) methods allow the detection and visualization of the genes/genomic regions of bacteria, archaea and infecting viruses at the single cell level. These methods use mixtures of polynucleotides as probes to specifically detect the target of interest. Gene-PROBER enables the design of polynucleotide mixtures for targeting genes or genomic regions in microorganisms. It has four workflows, depending on the availability of non-target sequences and the choice of probe synthesis, either by chemical synthesis or by PCR. It outputs polynucleotides that are spread along the target sequence and have similar melting properties. Therefore, such a polynucleotide mixture can be used as a single probe, in a single hybridization reaction. Gene-PROBER is a freely available web service that can be accessed at http://gene-prober.icbm.de/, and is implemented in the R language using the Shiny package.


Assuntos
Sondas de Oligonucleotídeos/química , Software , Archaea/genética , Bactérias/genética , Técnicas de Tipagem Bacteriana , Hibridização in Situ Fluorescente , Internet , Hibridização de Ácido Nucleico , Polinucleotídeos/química
15.
Nucleic Acids Res ; 48(22): 12593-12603, 2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33264400

RESUMO

Ribonucleoprotein (RNP) granules are membraneless organelles (MLOs), which majorly consist of RNA and RNA-binding proteins and are formed via liquid-liquid phase separation (LLPS). Experimental studies investigating the drivers of LLPS have shown that intrinsically disordered proteins (IDPs) and nucleic acids like RNA and other polynucleotides play a key role in modulating protein phase separation. There is currently a dearth of modelling techniques which allow one to delve deeper into how polynucleotides play the role of a modulator/promoter of LLPS in cells using computational methods. Here, we present a coarse-grained polynucleotide model developed to fill this gap, which together with our recently developed HPS model for protein LLPS, allows us to capture the factors driving protein-polynucleotide phase separation. We explore the capabilities of the modelling framework with the LAF-1 RGG system which has been well studied in experiments and also with the HPS model previously. Further taking advantage of the fact that the HPS model maintains sequence specificity we explore the role of charge patterning on controlling polynucleotide incorporation into condensates. With increased charge patterning we observe formation of structured or patterned condensates which suggests the possible roles of polynucleotides in not only shifting the phase boundaries but also introducing microscopic organization in MLOs.


Assuntos
Proteínas/genética , Proteínas de Ligação a RNA/genética , RNA/genética , Ribonucleoproteínas/genética , Simulação por Computador , Proteínas Intrinsicamente Desordenadas/genética , Extração Líquido-Líquido , Modelos Moleculares , Organelas/genética , Polinucleotídeos/química , Polinucleotídeos/genética , Domínios Proteicos/genética , Proteínas/química
17.
Nat Commun ; 11(1): 4628, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934220

RESUMO

Liquid phase separation into two or more coexisting phases has emerged as a new paradigm for understanding subcellular organization, prebiotic life, and the origins of disease. The design principles underlying biomolecular phase separation have the potential to drive the development of novel liquid-based organelles and therapeutics, however, an understanding of how individual molecules contribute to emergent material properties, and approaches to directly manipulate phase dynamics are lacking. Here, using microrheology, we demonstrate that droplets of poly-arginine coassembled with mono/polynucleotides have approximately 100 fold greater viscosity than comparable lysine droplets, both of which can be finer tuned by polymer length. We find that these amino acid-level differences can drive the formation of coexisting immiscible phases with tunable formation kinetics and can be further exploited to trigger the controlled release of droplet components. Together, this work provides a novel mechanism for leveraging sequence-level components in order to regulate droplet dynamics and multiphase coexistence.


Assuntos
Arginina/química , Lisina/química , Cinética , Transição de Fase , Polinucleotídeos/química , Viscosidade
18.
Int Wound J ; 17(6): 1702-1708, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32710584

RESUMO

Reconstruction of chronic ulcers is often hampered by lack of local tissues and poor general conditions. Conservative approaches with debridement and advanced medications, such as polyurethane foam, stand as mainstays. However, the healing process is often slow, thus increasing the risk for infection or other complications. In such cases, porcine dermis (PD) and polynucleotides-added hyaluronic acid (PAHA) were previously reported to accelerate healing. The aim of the study was to compare the efficacy of PD, PAHA and polyurethane foam in chronic ulcers. Thirty patients were randomly divided into 3 groups: group 1 was treated with advanced medications, group 2 with PD, group 3 with PAHA. Standardised photographs and biopsies were taken before treatment and at 30-day follow-up. Photographs were processed to calculate the wound area. Specimens were stained with Haematoxylin/Eosin, Masson trichrome, and immunohistochemically for CD34, alpha-Smooth Muscle Actin (α-SMA), Collagen types I and III, Ki67. The re-epithelialized area was larger in patients treated with PD and PAHA compared with those treated with polyurethane foam (P < .05 and P < .01, respectively). Specimens from patients treated with PD and PAHA showed a higher number of myofibroblasts (α-SMA+, P < .01), neo-angiogenesis (CD34+, P < .01), proliferating dermal cells (Ki67+, P < .01), proliferating keratinocytes (Ki67+, P < .01) and collagen type 1 deposition (P < .05). No difference was found between PD and PAHA. PD and PAHA proved to be more effective than polyurethane foam in the treatment of chronic ulcers. These approaches are a versatile and reliable option to address such cases.


Assuntos
Derme Acelular , Ácido Hialurônico , Úlcera Cutânea/terapia , Animais , Xenoenxertos/transplante , Humanos , Ácido Hialurônico/uso terapêutico , Polinucleotídeos/farmacologia , Poliuretanos , Método Simples-Cego , Suínos
19.
Medicine (Baltimore) ; 99(24): e20689, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32541518

RESUMO

BACKGROUND: The reduced range of motion and pain are the most characteristic clinical features of osteoarthritis (OA). Hyaluronic acid (HA), which is one of the infiltrative therapies for OA treatment, and polynucleotides (PNs), which is a DNA-derived macromolecule favored cell growth and collagen production, are an ongoing debate in clinical effectiveness. METHODS: We plan to perform a systematic review and meta-analysis of randomized clinical trial to evaluate efficacy of intra-articular polynucleotides associated with hyaluronic acid versus hyaluronic acid alone in the treatment of knee osteoarthritis. We will search PubMed, EMBASE, Cochrane Library using a comprehensive strategy. The related conference proceedings and reference lists of the included studies will also be checked to identify additional studies. Two reviewers will screen retrieved records, extract information and assess the risk of bias independently. Stata v15.1 software will be used to conduct data synthesis. RESULTS: This study will be submitted to a peer-reviewed journal for publication. CONCLUSION: We hope it will provide a relatively comprehensive reference for clinical practice and future relevant clinical trials. ETHICS AND DISSEMINATION: Ethics approval and patient consent are not required, as this study is a systematic review and meta-analysis. PROSPERO REGISTRATION NUMBER: CRD42020167678.


Assuntos
Artralgia/tratamento farmacológico , Ácido Hialurônico/administração & dosagem , Metanálise como Assunto , Osteoartrite do Joelho/complicações , Polinucleotídeos/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Projetos de Pesquisa , Revisões Sistemáticas como Assunto , Combinação de Medicamentos , Humanos , Injeções Intra-Articulares , Resultado do Tratamento
20.
BMC Evol Biol ; 20(1): 75, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590933

RESUMO

BACKGROUND: We hypothesize prebiotic evolution of self-replicating macro-molecules (Alberts, Molecular biology of the cell, 2015; Orgel, Crit Rev Biochem Mol Biol 39:99-123, 2004; Hud, Nat Commun 9:5171) favoured the constituent nucleotides and biophysical properties observed in the RNA and DNA of modern organisms. Assumed initial conditions are a shallow tide pool, containing a racemic mix of diverse nucleotide monomers (Barks et al., Chembiochem 11:1240-1243, 2010; Krishnamurthy, Nat Commun 9:5175, 2018; Hirao, Curr Opin Chem Biol 10:622-627), subject to day/night thermal fluctuations (Piccirilli et al., Nature 343:33-37, 1990). Self-replication, like Polymerase Chain Reactions, followed as higher daytime thermal energy "melted" inter-strand hydrogen bonds causing strand separation while solar UV radiation increased prebiotic nucleobase formation (Szathmary, Proc Biol Sci 245:91-99, 1991; Materese et al., Astrobiology 17:761-770, 2017; Bera et al., Astrobiology 17:771-785, 2017). Lower night energies allowed free monomers to form hydrogen bonds with their template counterparts leading to daughter strand synthesis (Hirao, Biotechniques 40:711, 2006). RESULTS: Evolutionary selection favoured increasing strand length to maximize auto-catalytic function in RNA and polymer stability in double stranded DNA (Krishnamurthy, Chemistry 24:16708-16715, 2018; Szathmary, Nat Rev Genet 4:995-1001, 2003). However, synthesis of the full daughter strand before daytime temperatures produced strand separation, longer polymer length required increased speed of self-replication. Computer simulations demonstrate optimal polynucleotide autocatalytic speed is achieved when the constituent nucleotides possess a left-right asymmetry that decreases the hydrogen bond kinetic barrier for the free nucleotide attachment to the template on one side and increases bond barrier on the other side preventing it from releasing prior to covalent bond formation. This phenomenon is similar to asymmetric kinetics observed during polymerization of the front and the back ends of linear cytoskeletal proteins such as actin and microtubules (Orgel, Nature 343:18-20, 1990; Henry, Curr Opin Chem Biol 7:727-733, 2003; Walker et al., J Cell Biol 108:931-937, 1989; Crevenna et al., J Biol Chem 288:12102-12113, 2013). Since rotation of the nucleotide would disrupt the asymmetry, the optimal nucleotides must form two or more hydrogen bonds with their counterpart on the template strand. All nucleotides in modern RNA and DNA have these predicted properties. Our models demonstrate these constraints on the properties of constituent monomers result in biophysical properties found in modern DNA and RNA including strand directionality, anti-parallel strand orientation, homochirality, quadruplet alphabet, and complementary base pairing. Furthermore, competition between RNA and DNA auto-replicators for 3 nucleotides in common permit states coexistence and possible cooperative interactions that could be incorporated into nascent living systems. CONCLUSION: Our findings demonstrate the molecular properties of DNA/RNA could have emerged from Darwinian competition among macromolecular replicators that selected nucleotide monomers that maximized the speed of autocatalysis.


Assuntos
Replicação do DNA , DNA/biossíntese , Polinucleotídeos/biossíntese , Prebióticos , RNA/biossíntese , DNA/genética , Cinética , Polinucleotídeos/genética , RNA/genética
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