Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 59
Filter
1.
Phys Rev Lett ; 133(9): 098401, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39270162

ABSTRACT

AI algorithms have proven to be excellent predictors of protein structure, but whether and how much these algorithms can capture the underlying physics remains an open question. Here, we aim to test this question using the Alphafold2 (AF) algorithm: We use AF to predict the subtle structural deformation induced by single mutations, quantified by strain, and compare with experimental datasets of corresponding perturbations in folding free energy ΔΔG. Unexpectedly, we find that physical strain alone-without any additional data or computation-correlates almost as well with ΔΔG as state-of-the-art energy-based and machine-learning predictors. This indicates that the AF-predicted structures alone encode fine details about the energy landscape. In particular, the structures encode significant information on stability, enough to estimate (de-)stabilizing effects of mutations, thus paving the way for the development of novel, structure-based stability predictors for protein design and evolution.


Subject(s)
Algorithms , Protein Folding , Proteins , Thermodynamics , Proteins/chemistry , Proteins/genetics , Proteins/metabolism , Artificial Intelligence , Mutation , Protein Conformation
3.
Sci Adv ; 10(20): eadm9797, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38748798

ABSTRACT

Both music and language are found in all known human societies, yet no studies have compared similarities and differences between song, speech, and instrumental music on a global scale. In this Registered Report, we analyzed two global datasets: (i) 300 annotated audio recordings representing matched sets of traditional songs, recited lyrics, conversational speech, and instrumental melodies from our 75 coauthors speaking 55 languages; and (ii) 418 previously published adult-directed song and speech recordings from 209 individuals speaking 16 languages. Of our six preregistered predictions, five were strongly supported: Relative to speech, songs use (i) higher pitch, (ii) slower temporal rate, and (iii) more stable pitches, while both songs and speech used similar (iv) pitch interval size and (v) timbral brightness. Exploratory analyses suggest that features vary along a "musi-linguistic" continuum when including instrumental melodies and recited lyrics. Our study provides strong empirical evidence of cross-cultural regularities in music and speech.


Subject(s)
Language , Music , Speech , Humans , Speech/physiology , Male , Pitch Perception/physiology , Female , Adult , Pre-Registration Publication
4.
Phys Rev Lett ; 131(21): 218401, 2023 Nov 24.
Article in English | MEDLINE | ID: mdl-38072605

ABSTRACT

AlphaFold2 (AF) is a promising tool, but is it accurate enough to predict single mutation effects? Here, we report that the localized structural deformation between protein pairs differing by only 1-3 mutations-as measured by the effective strain-is correlated across 3901 experimental and AF-predicted structures. Furthermore, analysis of ∼11 000 proteins shows that the local structural change correlates with various phenotypic changes. These findings suggest that AF can predict the range and magnitude of single-mutation effects on average, and we propose a method to improve precision of AF predictions and to indicate when predictions are unreliable.


Subject(s)
Mutation , Proteins , Software , Proteins/genetics
5.
PLoS One ; 18(12): e0284851, 2023.
Article in English | MEDLINE | ID: mdl-38091315

ABSTRACT

Scales, sets of discrete pitches that form the basis of melodies, are thought to be one of the most universal hallmarks of music. But we know relatively little about cross-cultural diversity of scales or how they evolved. To remedy this, we assemble a cross-cultural database (Database of Musical Scales: DaMuSc) of scale data, collected over the past century by various ethnomusicologists. Statistical analyses of the data highlight that certain intervals (e.g., the octave, fifth, second) are used frequently across cultures. Despite some diversity among scales, it is the similarities across societies which are most striking: step intervals are restricted to 100-400 cents; most scales are found close to equidistant 5- and 7-note scales. We discuss potential mechanisms of variation and selection in the evolution of scales, and how the assembled data may be used to examine the root causes of convergent evolution.


Subject(s)
Music , Cross-Cultural Comparison
6.
Sci Rep ; 13(1): 16264, 2023 Sep 27.
Article in English | MEDLINE | ID: mdl-37758776

ABSTRACT

In this report, the development of a Dynamical Statistical Analog Ensemble Forecast model for landfalling typhoon disasters (LTDs) and some applications over coastal China are described. This model consists of the following four elements: (i) obtaining the forecast track of a target landfalling typhoon, (ii) constructing its generalized initial value (GIV), (iii) identifying its analogs based on the GIV, and (iv) assembling typhoon disasters of the analogs. Typhoon track, intensity, and landfall date are introduced in GIV at this early development stage. The pre-assessment results show that the mean threat scores of two important damage levels of LTDs reach 0.48 and 0.55, respectively. Of significance is that most of the damage occurs near the typhoon centers around the time of landfall. These results indicate the promising performance of the model in capturing the main damage characteristics of typhoon disasters, which would help coastal community mitigate damage from destructive typhoons.

7.
Violence Against Women ; : 10778012231189479, 2023 Jul 28.
Article in English | MEDLINE | ID: mdl-37501604

ABSTRACT

This research determines the prevalence of intimate partner violence against women (IPVAW) and its impact on labor productivity in the financial sector of two Latin American countries. Nine financial institutions participated in this study with surveys of 892 female employees in Bolivia and 393 in Paraguay. The results revealed that 40.1% in Bolivia and 18.7% in Paraguay experienced IPVAW. In Bolivia, this resulted in 6.686 lost workdays per year due to absenteeism and 7.640 workdays per year due to presenteeism (present but distracted). In Paraguay, 12.035 days were lost to absenteeism and 12.037 to presenteeism. This pioneering research highlights the significant influence of IPVAW on financial sector productivity and its broader economic implications.

8.
PLoS One ; 17(11): e0275469, 2022.
Article in English | MEDLINE | ID: mdl-36322519

ABSTRACT

Standardized cross-cultural databases of the arts are critical to a balanced scientific understanding of the performing arts, and their role in other domains of human society. This paper introduces the Global Jukebox as a resource for comparative and cross-cultural study of the performing arts and culture. The Global Jukebox adds an extensive and detailed global database of the performing arts that enlarges our understanding of human cultural diversity. Initially prototyped by Alan Lomax in the 1980s, its core is the Cantometrics dataset, encompassing standardized codings on 37 aspects of musical style for 5,776 traditional songs from 1,026 societies. The Cantometrics dataset has been cleaned and checked for reliability and accuracy, and includes a full coding guide with audio training examples (https://theglobaljukebox.org/?songsofearth). Also being released are seven additional datasets coding and describing instrumentation, conversation, popular music, vowel and consonant placement, breath management, social factors, and societies. For the first time, all digitized Global Jukebox data are being made available in open-access, downloadable format (https://github.com/theglobaljukebox), linked with streaming audio recordings (theglobaljukebox.org) to the maximum extent allowed while respecting copyright and the wishes of culture-bearers. The data are cross-indexed with the Database of Peoples, Languages, and Cultures (D-PLACE) to allow researchers to test hypotheses about worldwide coevolution of aesthetic patterns and traditions. As an example, we analyze the global relationship between song style and societal complexity, showing that they are robustly related, in contrast to previous critiques claiming that these proposed relationships were an artifact of autocorrelation (though causal mechanisms remain unresolved).


Subject(s)
Music , Humans , Reproducibility of Results , Cross-Cultural Comparison , Language , Databases, Factual , Culture
9.
Mol Biol Evol ; 39(11)2022 11 03.
Article in English | MEDLINE | ID: mdl-36208205

ABSTRACT

Proteins need to selectively interact with specific targets among a multitude of similar molecules in the cell. However, despite a firm physical understanding of binding interactions, we lack a general theory of how proteins evolve high specificity. Here, we present such a model that combines chemistry, mechanics, and genetics and explains how their interplay governs the evolution of specific protein-ligand interactions. The model shows that there are many routes to achieving molecular discrimination-by varying degrees of flexibility and shape/chemistry complementarity-but the key ingredient is precision. Harder discrimination tasks require more collective and precise coaction of structure, forces, and movements. Proteins can achieve this through correlated mutations extending far from a binding site, which fine-tune the localized interaction with the ligand. Thus, the solution of more complicated tasks is enabled by increasing the protein size, and proteins become more evolvable and robust when they are larger than the bare minimum required for discrimination. The model makes testable, specific predictions about the role of flexibility and shape mismatch in discrimination, and how evolution can independently tune affinity and specificity. Thus, the proposed theory of specific binding addresses the natural question of "why are proteins so big?". A possible answer is that molecular discrimination is often a hard task best performed by adding more layers to the protein.


Subject(s)
Models, Chemical , Proteins , Ligands , Proteins/genetics , Proteins/chemistry , Binding Sites , Protein Binding
10.
Biophys J ; 120(24): 5466-5477, 2021 12 21.
Article in English | MEDLINE | ID: mdl-34813729

ABSTRACT

Proteins are translated from the N to the C terminus, raising the basic question of how this innate directionality affects their evolution. To explore this question, we analyze 16,200 structures from the Protein Data Bank (PDB). We find remarkable enrichment of α helices at the C terminus and ß strands at the N terminus. Furthermore, this α-ß asymmetry correlates with sequence length and contact order, both determinants of folding rate, hinting at possible links to co-translational folding (CTF). Hence, we propose the "slowest-first" scheme, whereby protein sequences evolved structural asymmetry to accelerate CTF: the slowest of the cooperatively folding segments are positioned near the N terminus so they have more time to fold during translation. A phenomenological model predicts that CTF can be accelerated by asymmetry in folding rate, up to double the rate, when folding time is commensurate with translation time; analysis of the PDB predicts that structural asymmetry is indeed maximal in this regime. This correspondence is greater in prokaryotes, which generally require faster protein production. Altogether, this indicates that accelerating CTF is a substantial evolutionary force whose interplay with stability and functionality is encoded in secondary structure asymmetry.


Subject(s)
Protein Biosynthesis , Protein Folding , Databases, Protein , Protein Structure, Secondary , Proteins/chemistry
11.
Int J Pharm ; 596: 120223, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33508341

ABSTRACT

RALA is a cationic amphipathic peptide which has shown great promise as an efficient, multifunctional delivery system for the delivery of nucleic acids. Rational peptide design was utilised in this study to understand the essential amino acids required for delivery and if any improvements to the RALA peptide could be made. Six amphipathic peptides were synthesised with strategic sequences and amino acid substitutions to reduce peptide sequence, while maintaining the functional characteristics of RALA including amphipathicity, alpha-helicity and pH responsiveness for endosomal escape. Data demonstrated that all six peptides complexed pEGFP-N1 to produce cationic nanoparticles <200 nm in diameter, but not all peptides resulted in successful transfection; indicating the influence of peptide design for cellular uptake and endosomal escape. Pep2, produced nanoparticles with similar characteristics and transfection efficiency to the parent peptide, RALA. However, Pep2 had issues with toxicity and a lack of pH-responsive alpha-helcity. Therefore, RALA remains the superior sequence for non-toxic gene delivery.


Subject(s)
Cell-Penetrating Peptides , Nanoparticles , Gene Transfer Techniques , Genetic Therapy , Transfection
12.
J Control Release ; 330: 1288-1299, 2021 02 10.
Article in English | MEDLINE | ID: mdl-33227336

ABSTRACT

The design of a non-viral gene delivery system that can release a functional nucleic acid at the intracellular destination site is an exciting but also challenging proposition. The ideal gene delivery vector must be non-toxic, non-immunogenic, overcome extra- and intra-cellular barriers, protect the nucleic acid cargo from degradation with stability over a range of temperatures. A new 15 amino acid linear peptide termed CHAT was designed in this study with the goal of delivering DNA with high efficiency into cells in vitro and tissues in vivo. Rational design involved incorporation of key amino acids including arginine for nucleic acid complexation and cellular uptake, tryptophan to enhance hydrophobic interaction with cell membranes, histidine to facilitate endosomal escape and cysteine for stability and controlled cargo release. Six linear peptides were synthesised with strategic sequences and amino acid substitutions. Data demonstrated that all six peptides complexed pDNA to produce cationic nanoparticles less than 200 nm in diameter, but not all peptides resulted in successful transfection; indicating the influence of peptide design for endosomal escape. Peptide 4, now termed CHAT, was non-cytotoxic, traversed the plasma membrane of breast and prostate cancer cell lines, and elicited reporter-gene expression following intra-tumoural and intravenous delivery in vivo. CHAT presents an exciting new peptide for the delivery of nucleic acid therapeutics.


Subject(s)
Cell-Penetrating Peptides , Gene Transfer Techniques , Genetic Therapy , Plasmids , Transfection
13.
J Med Internet Res ; 22(11): e17150, 2020 11 27.
Article in English | MEDLINE | ID: mdl-33245280

ABSTRACT

BACKGROUND: Three-dimensional scans are increasingly used to quantify biological topographical changes and clinical health outcomes. Traditionally, the use of 3D scans has been limited to specialized centers owing to the high cost of the scanning equipment and the necessity for complex analysis software. Technological advances have made cheaper, more accessible methods of data capture and analysis available in the field of dentistry, potentially facilitating a primary care system to quantify disease progression. However, this system has yet to be compared with previous high-precision methods in university hospital settings. OBJECTIVE: The aim of this study was to compare a dental primary care method of data capture (intraoral scanner) with a precision hospital-based method (laser profilometer) in addition to comparing open source and commercial software available for data analysis. METHODS: Longitudinal dental wear data from 30 patients were analyzed using a two-factor factorial experimental design. Bimaxillary intraoral digital scans (TrueDefinition, 3M, UK) and conventional silicone impressions, poured in type-4 dental stone, were made at both baseline and follow-up appointments (mean 36 months, SD 10.9). Stone models were scanned using precision laser profilometry (Taicaan, Southampton, UK). Three-dimensional changes in both forms of digital scans of the first molars (n=76) were quantitatively analyzed using the engineering software Geomagic Control (3D Systems, Germany) and freeware WearCompare (Leeds Digital Dentistry, UK). Volume change (mm3) was the primary measurement outcome. The maximum point loss (µm) and the average profile loss (µm) were also recorded. Data were paired and skewed, and were therefore compared using Wilcoxon signed-rank tests with Bonferroni correction. RESULTS: The median (IQR) volume change for Geomagic using profilometry and using the intraoral scan was -0.37 mm3 (-3.75-2.30) and +0.51 mm3 (-2.17-4.26), respectively (P<.001). Using WearCompare, the median (IQR) volume change for profilometry and intraoral scanning was -1.21 mm3 (-3.48-0.56) and -0.39 mm3 (-3.96-2.76), respectively (P=.04). WearCompare detected significantly greater volume loss than Geomagic regardless of scanner type. No differences were observed between groups with respect to the maximum point loss or average profile loss. CONCLUSIONS: As expected, the method of data capture, software used, and measurement metric all significantly influenced the measurement outcome. However, when appropriate analysis was used, the primary care system was able to quantify the degree of change and can be recommended depending on the accuracy needed to diagnose a condition. Lower-resolution scanners may underestimate complex changes when measuring at the micron level.


Subject(s)
Computer-Aided Design/instrumentation , Imaging, Three-Dimensional/methods , Mouth/pathology , Adult , Female , Germany , Humans , Longitudinal Studies , Male , Research Design , Software
14.
Int J Pharm ; 564: 207-213, 2019 Jun 10.
Article in English | MEDLINE | ID: mdl-30999049

ABSTRACT

The past fifteen years have witnessed a resurgence of interest in vaginal ring technologies for drug delivery applications, mostly driven by the impetus for development of vaginally-administered antiretroviral microbicides to help reduce the high acquisition rates for human immunodeficiency virus (HIV) among Sub-Saharan African women. Currently, the lead candidate microbicide is a 28-day silicone elastomer vaginal ring releasing dapivirine (Ring-004), an experimental non-nucleoside reverse transcriptase inhibitor. The ring was tested in two pivotal Phase III clinical studies in 2016 and is currently undergoing review by the European Medicines Agency. Recently, we described a new type of silicone elastomer vaginal ring offering sustained release of the protein molecule 5P12-RANTES, a potent experimental chemokine analogue that potently blocks the HIV CCR5 coreceptor. Building on our previous work, here we report the preclinical development of a new combination vaginal ring that offers sustained release of both 5P12-RANTES and dapivirine, in which the 5P12-RANTES is incorporated into an exposed core within the ring body and the dapivirine in the sheath. In this way, in vitro release of dapivirine matches closely that for Ring-004. Also, we report the pharmacokinetic testing of this combination ring formulation in sheep, where vaginal concentrations of both drugs are maintained over 28 days at levels potentially useful for preventing HIV infection in women.


Subject(s)
Anti-HIV Agents/administration & dosage , Chemokines, CC/administration & dosage , Contraceptive Devices, Female , HIV Infections/prevention & control , Pyrimidines/administration & dosage , Animals , Anti-HIV Agents/pharmacokinetics , Chemokines, CC/pharmacokinetics , Delayed-Action Preparations/administration & dosage , Drug Combinations , Female , Pyrimidines/pharmacokinetics , Sheep , Vagina/metabolism
15.
Int J Mycobacteriol ; 8(1): 48-52, 2019.
Article in English | MEDLINE | ID: mdl-30860179

ABSTRACT

BACKGROUND: Buruli ulcer (BU), regionally known as the Daintree ulcer or Bairnsdale ulcer is caused by the environmental pathogen Mycobacterium ulcerans (MU). This disease is characterized by extensive and painless necrosis of skin and soft tissue with the formation of large ulcers and has been reported in >33 countries worldwide. This organism is geographically restricted and in Australia, the disease has been reported primarily in coastal Victoria and the Mossman-Daintree areas of northern Queensland. Australia is the only country where nonhuman cases of BU have been confirmed. The common ringtail possums and mountain brushtail possums have been suggested as potential animal reservoirs of MU in coastal Victoria, Australia. The exact mode of transmission of this disease remains unknown. METHODS: In this study, we surveyed local fauna from endemic areas of northern Queensland, Australia, for the presence of MU in scat samples. We collected 140 bandicoot, four white-tailed rats, and two possum scat samples from 56 overnight trapping sessions. Samples were examined for the presence of MU DNA by the polymerase chain reaction. RESULTS: Two out of five samples did not contain a sufficient amount of DNA to detect IS2606 and the ketoreductase B (KR) domain of the mycolactone polyketide synthase gene, which is represented by higher cycle threshold (Ct) values for IS2404 shown in table below. Despite of having desired Ct values for IS2404, one IS2404 positive sample possibly contained DNA of closely related M. ulcerans subspecies with lower copy number of IS2606 that do not commonly cause disease in human. All three targets: IS2404, IS2606 and KR were detected from the remaining two scat samples. CONCLUSION: We confirm the presence of M. ulcerans DNA in the scat samples collected from a Buruli ulcer endemic region of Northern Queensland, Australia.


Subject(s)
Buruli Ulcer/epidemiology , Ecosystem , Endemic Diseases , Environmental Microbiology , Feces/microbiology , Mycobacterium ulcerans/isolation & purification , Animals , DNA, Bacterial/genetics , DNA, Bacterial/isolation & purification , Humans , Mycobacterium ulcerans/genetics , Polymerase Chain Reaction , Queensland/epidemiology , Rats
16.
J Control Release ; 298: 1-11, 2019 03 28.
Article in English | MEDLINE | ID: mdl-30731150

ABSTRACT

Antiretroviral-releasing vaginal rings are at the forefront of ongoing efforts to develop microbicide-based strategies for prevention of heterosexual transmission of the human immunodeficiency virus (HIV). However, traditional ring designs are generally only useful for vaginal administration of relatively potent, lipophilic, and small molecular weight drug molecules that have sufficient permeability in the non-biodegradable silicone elastomer or thermoplastic polymers. Here, we report a novel, easy-to-manufacture 'exposed-core' vaginal ring that provides sustained release of the protein microbicide candidate 5P12-RANTES, an experimental chemokine analogue that potently blocks the HIV CCR5 coreceptor. In vitro release, mechanical, and stability testing demonstrated the utility and practicality of this novel ring design. In a sheep pharmacokinetic model, a ring containing two »-length excipient-modified silicone elastomer cores - each containing lyophilised 5P12-RANTES and exposed to the external environment by two large windows - provided sustained concentrations of 5P12-RANTES in vaginal fluid and vaginal tissue between 10 and 10,000 ng/g over 28days, at least 50 and up to 50,000 times the reported in vitro IC50 value.


Subject(s)
CCR5 Receptor Antagonists/administration & dosage , Chemokines, CC/administration & dosage , Contraceptive Devices, Female , Drug Delivery Systems , Administration, Intravaginal , Animals , Anti-HIV Agents/administration & dosage , Anti-HIV Agents/pharmacokinetics , CCR5 Receptor Antagonists/pharmacokinetics , Chemokines, CC/pharmacokinetics , Delayed-Action Preparations , Female , HIV Infections/prevention & control , Humans , Inhibitory Concentration 50 , Sheep
18.
Healthcare (Basel) ; 6(3)2018 Jul 06.
Article in English | MEDLINE | ID: mdl-29986398

ABSTRACT

Current research around effective recruitment strategies for clinical trials of dietary obesity treatments have largely focused on younger adults, and thus may not be applicable to older populations. The TEMPO Diet Trial (Type of Energy Manipulation for Promoting optimal metabolic health and body composition in Obesity) is a randomised controlled trial comparing the long-term effects of fast versus slow weight loss on body composition and cardio-metabolic health in postmenopausal women with obesity. This paper addresses the recruitment strategies used to enrol participants into this trial and evaluates their relative effectiveness. 101 post-menopausal women aged 45⁻65 years, with a body mass index of 30⁻40 kg/m² were recruited and randomised to either fast or slow weight loss. Multiple strategies were used to recruit participants. The total time cost (labour) and monetary cost per randomised participant from each recruitment strategy was estimated, with lower values indicating greater cost-effectiveness and higher values indicating poorer cost-effectiveness. The most cost-effective recruitment strategy was word of mouth, followed (at equal second place) by free publicity on TV and radio, and printed advertorials, albeit these avenues only yielded 26/101 participants. Intermediate cost-effective recruitment strategies were flyer distribution at community events, hospitals and a local tertiary education campus, internet-based strategies, and clinical trial databases and intranets, which recruited a further 40/101 participants. The least cost-effective recruitment strategy was flyer distribution to local health service centres and residential mailboxes, and referrals from healthcare professionals were not effective. Recruiting for clinical trials involving postmenopausal women could benefit from a combination of recruitment strategies, with an emphasis on word of mouth and free publicity via radio, TV, and print media, as well as strategic placement of flyers, supplemented with internet-based strategies, databases and intranets if a greater yield of participants is needed.

19.
Cancer Nanotechnol ; 9(1): 5, 2018.
Article in English | MEDLINE | ID: mdl-29899810

ABSTRACT

BACKGROUND: Recent approvals of gene therapies by the FDA and the EMA for treatment of inherited disorders have further opened the door for assessment of nucleic acid pharmaceuticals for clinical usage. Arising from the presence of damaged or inappropriate DNA, cancer is a condition particularly suitable for genetic intervention. The RALA peptide has been shown to be a potent non-viral delivery platform for nucleic acids. This study examines the use of RALA to deliver a plasmid encoding inducible nitric oxide synthase (iNOS) as an anti-cancer treatment. METHODS: The physiochemical properties of the RALA/DNA nanoparticles were characterized via dynamic light scattering and transmission electron microscopy. The nanoparticles were labelled with fluorophores and tracked over time using confocal microscopy with orthogonal sections to determine cellular location. In vitro studies were employed to determine functionality of the nanoparticles both for pEGFP-N1 and CMV-iNOS. Nanoparticles were injected intravenously into C57/BL6 mice with blood and serum samples analysed for immune response. PC3-luc2M cells were injected into the left ventricle of SCID mice followed by treatment with RALA/CMV-iNOS nanoparticles to evaluate the tumour response in a metastatic model of prostate cancer. RESULTS: Functional cationic nanoparticles were produced with gene expression in PC-3 prostate cancer cells. Furthermore, repeated administrations of RALA/DNA nanoparticles into immunocompetent mice did not produce any immunological response: neutralization of the vector or release of inflammatory mediators. RALA/CMV-iNOS reduced the clonogenicity of PC-3 cells in vitro, and in an in vivo model of prostate cancer metastasis, systemically delivered RALA/CMV-iNOS significantly improved the survival of mice. CONCLUSION: These studies further validate RALA as a genetic cargo delivery vehicle and iNOS as a potent therapy for the treatment of cancer.

20.
Eur J Pharm Biopharm ; 127: 288-297, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29510205

ABSTRACT

Dissolvable microneedles can be employed to deliver DNA to antigen presenting cells within the skin. However, this technology faces two main challenges: the poor transfection efficacy of pDNA following release from the microneedle matrix, and the limited loading capacity of the micron-scale devices. Two-tier delivery systems combining microneedle platforms and DNA delivery vectors have increased efficacy but the challenge of increasing the loading capacity remains. This study utilised lyophilisation to increase the loading of RALA/pDNA nanoparticles within dissolvable PVA microneedles. As a result, delivery was significantly enhanced in vivo into an appropriate range for DNA vaccination (∼50 µg per array). Furthermore, modifying the manufacturing process was not detrimental to the microneedle mechanical properties or cargo functionality. It was demonstrated that arrays retained mechanical and functional stability over short term storage, and were able to elicit gene expression in vitro and in vivo. Finally, treatment with this novel formulation significantly retarded the growth of established tumours, and proved superior to standard intramuscular injection in a preclinical model of cervical cancer.


Subject(s)
DNA/administration & dosage , DNA/chemistry , Peptides/chemistry , Uterine Cervical Neoplasms/drug therapy , Vaccines, DNA/administration & dosage , Vaccines, DNA/chemistry , Animals , Biodegradable Plastics/chemistry , Cell Line , Drug Delivery Systems/methods , Female , Gene Transfer Techniques , Genetic Therapy/methods , Injections, Intramuscular/methods , Mice , Mice, Inbred C57BL , Microinjections/methods , Nanoparticles/chemistry , Needles , Plasmids/administration & dosage , Skin/metabolism , Swine , Transfection/methods , Vaccination/methods
SELECTION OF CITATIONS
SEARCH DETAIL