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2.
Cancers (Basel) ; 14(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35326659

RESUMO

Mycosis fungoides (MF) is a subtype of CTCL with a low incidence and high medical need for novel treatments. The objective of this randomized, placebo-controlled, double-blinded, first-in-human study was to evaluate safety, efficacy, cutaneous and systemic pharmacokinetics (PK) of topical bimiralisib in healthy volunteers (HVs) and MF patients. In this trial, a total of 6 HVs and 19 early-stage MF patients were treated with 2.0% bimiralisib gel and/or placebo. Drug efficacy was assessed by the Composite Assessment of Index Lesion Severity (CAILS) score, supported by objective measuring methods to quantify lesion severity. PK blood samples were collected frequently and cutaneous PK was investigated in skin punch biopsies on the last day of treatment. Local distribution of bimiralisib in HVs showed a mean exposure of 2.54 µg/g in the epidermis. A systemic concentration was observed after application of a target dose of 2 mg/cm2 on 400 cm2, with a mean Cavg of 0.96 ng/mL. Systemic exposure of bimiralisib was reached in all treated MF patients, and normalized plasma concentrations showed a 144% increased exposure compared to HVs, with an observed mean Cavg of 4.49 ng/mL and a mean cutaneous concentration of 5.3 µg/g. No difference in CAILS or objective lesion severity quantification upon 42 days of once-daily treatment was observed in the MF patient group. In general, the treatment was well tolerated in terms of local reactions as well as systemic adverse events. In conclusion, we showed that topical bimiralisib treatment leads to (i) meaningful cutaneous drug levels and (ii) well-tolerated systemic drug exposure in MF patients and (iii) a lack of clinical efficacy, in need of further exploration due to numerous unknown factors, before depreciation of topical bimiralisib as a novel therapeutic drug for CTCLs.

3.
ACS Appl Mater Interfaces ; 13(8): 9445-9456, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33528240

RESUMO

Glaucoma is the second leading cause of irreversible blindness worldwide. Among others, elevated intraocular pressure (IOP) is one of the hallmarks of the disease. Antiglaucoma drugs such as brimonidine can lower the IOP but their adherence to the ocular surface is low, leading to a low drug uptake. This results in a frequent dropping regime causing low compliance by the patients. Lipid DNA nanoparticles (NPs) have the intrinsic ability to bind to the ocular surface and can be loaded with different drugs. Here, we report DNA NPs functionalized for loading of brimonidine through specific aptamers and via hydrophobic interactions with double stranded micelles. Both NP systems exhibited improved affinity toward the cornea and retained release of the drug as compared to controls both in vitro and in vivo. Both NP types were able to lower the IOP in living animals significantly more than pristine brimonidine. Importantly, the brimonidine-loaded NPs showed no toxicity and improved efficacy and hence should improve compliance. In conclusion, this drug-delivery system offers high chances of an improved treatment for glaucoma and thus preserving vision in the aging population.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/uso terapêutico , Tartarato de Brimonidina/uso terapêutico , DNA/química , Portadores de Fármacos/química , Glaucoma/tratamento farmacológico , Nanopartículas/química , Agonistas de Receptores Adrenérgicos alfa 2/química , Agonistas de Receptores Adrenérgicos alfa 2/toxicidade , Animais , Sequência de Bases , Tartarato de Brimonidina/química , Tartarato de Brimonidina/toxicidade , DNA/toxicidade , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Feminino , Interações Hidrofóbicas e Hidrofílicas , Pressão Intraocular/efeitos dos fármacos , Camundongos Endogâmicos DBA , Micelas , Nanopartículas/toxicidade , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/toxicidade , Ratos
4.
Org Biomol Chem ; 18(47): 9606-9610, 2020 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-33237073

RESUMO

The aptameric protective group strategy for the one-step regioselective transformation of aminoglycoside antibiotics was found to be compatible with diverse reagents and reaction conditions. New derivatives of neomycin B were synthesized with regioselectivities of >99%. This result extends the scope of applicability of APGs facilitating access to novel aminoglycoside derivatives.


Assuntos
Framicetina
5.
Nanomedicine ; 29: 102260, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32629041

RESUMO

Lipid DNA nanoparticles (NPs) exhibit an intrinsic affinity to the ocular surface and can be loaded by hybridization with fluorophore-DNA conjugates or with the anti-glaucoma drug travoprost by hybridizing an aptamer that binds the medication. In the travoprost-loaded NPs (Trav-NPs), the drug is bound by specific, non-covalent interactions, not requiring any chemical modification of the active pharmaceutical ingredient. Fluorescently labeled Trav-NPs show a long-lasting adherence to the eye, up to sixty minutes after eye drop instillation. Biosafety of the Trav-NPs was proved and in vivo. Ex vivo and in vivo quantification of travoprost via LC-MS revealed that Trav-NPs deliver at least twice the amount of the drug at every time-point investigated compared to the pristine drug. The data successfully show the applicability of a DNA-based drug delivery system in the field of ophthalmology for the treatment of a major retinal eye disease, i.e. glaucoma.


Assuntos
DNA/química , Sistemas de Liberação de Medicamentos , Glaucoma/tratamento farmacológico , Nanopartículas/química , Animais , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/farmacologia , Contenção de Riscos Biológicos , DNA/farmacologia , Modelos Animais de Doenças , Humanos , Lipídeos/química , Lipídeos/farmacologia , Camundongos , Ratos , Suínos , Travoprost/química , Travoprost/farmacologia
6.
Ortop Traumatol Rehabil ; 20(3): 189-195, 2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-30152774

RESUMO

BACKGROUND: Pain significantly decreases the quality of life. The treatment of back pain relies heavily on comprehensive rehabilitation. This study compared the effectiveness of deep electromagnetic stimulation and radial shock wave therapy in the opinion of patients with back pain of various aetiology. MATERIAL AND METHODS: The study group consisted of 73 subjects, of whom 36 patients underwent radial shock wave therapy and 37 patients underwent deep electromagnetic stimulation. All patients had a diagnosis of discopathy or osteoarthritis in the cervical or lumbar spine. Data were collected by means of an original ano-nymous questionnaire. RESULTS: Both groups demonstrated a reduction in pain intensity after a series of their respective treatments (p=0.03). There were no statistically significant differences in pain intensity between the groups directly on com-pletion of the treatment (p=0.227) and at 2 weeks (p=0.058) and 1 month after the treatment (p=0.084). CONCLUSION: Deep electromagnetic stimulation and radial shock wave therapy provide similarly satisfac-tory analgesic outcomes in patients with back pain.


Assuntos
Tratamento por Ondas de Choque Extracorpóreas/métodos , Dor Lombar/terapia , Vértebras Lombares/lesões , Osteoartrite/terapia , Terapia por Ultrassom/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Inquéritos e Questionários , Resultado do Tratamento
7.
Biomaterials ; 157: 98-106, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29258013

RESUMO

Nucleic acids represent very appealing building blocks for the construction of nano-scaled objects with great potential applications in the field of drug delivery where multifunctional nanoparticles (NPs) play a pivotal role. One opportunity for DNA nanotechnology lies in the treatment of ophthalmic diseases as the efficacy of eye drops is impaired by the short survival time of the drug on the eye surface. As a consequence, topical administration of ocular therapeutics requires high drug doses and frequent administration, still rarely providing high bioavailability. To overcome these shortcomings we introduce a novel and general carrier system that is based on DNA nanotechnology. Non-toxic, lipid-modified DNA strands (12mers with 4 lipid modified thymines at the 5' end) form uniform NPs (micelles), which adhere to the corneal surface for extended periods of time. In a single self-assembly step they can be equipped with different drugs by hybridization with an aptamer. The long survival times of DNA NPs can be translated into improved efficacy. Their functionality was demonstrated in several ex-vivo experiments and in an in-vivo animal model. Finally, the NPs were confirmed to be applicable even for human tissue.


Assuntos
DNA/administração & dosagem , Sistemas de Liberação de Medicamentos , Oftalmopatias/terapia , Nanopartículas/administração & dosagem , Soluções Oftálmicas/administração & dosagem , Administração Oftálmica , Animais , Córnea/metabolismo , DNA/química , Oftalmopatias/genética , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Micelas , Nanopartículas/química , Suínos
8.
Chemistry ; 23(39): 9391-9396, 2017 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-28513997

RESUMO

Anchoring DNA via hydrophobic units into the membrane of vesicles allows tagging of these nanocontainers with sequence information. Moreover, the hybridization of DNA on the surface of liposomes enables sequence specific functionalization, vesicle aggregation, and vesicle fusion. Specifically, DNA-hybridization-based approaches for fusion employing oligonucleotides terminally modified with one or two anchoring units were hindered by a limited degree of full fusion or by significant leakage during fusion. The current work deals with a new strategy for anchoring oligonucleotides on a membrane by lipid-modified nucleobases rather than by attaching hydrophobic units to the 3'- or 5'-termini. The lipid anchors were incorporated into the DNA sequence via phosphoramidite nucleotide building blocks during automated solid-phase synthesis allowing variation of the number and position of hydrophobic units along the DNA backbone. Single-stranded DNA functionalized with four lipid-modified nucleobases was stably grafted onto the membrane of lipid vesicles. It was found that the orientation of DNA hybridization and the number of anchoring units play a crucial role in liposomal fusion, which in the most efficient system reached remarkable 29 % content mixing without notable leakage.


Assuntos
DNA de Cadeia Simples/química , Lipossomos/química , Microscopia Crioeletrônica , Difusão Dinâmica da Luz , Transferência Ressonante de Energia de Fluorescência , Interações Hidrofóbicas e Hidrofílicas , Hibridização de Ácido Nucleico
9.
Biomaterials ; 115: 81-89, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27886556

RESUMO

We introduce a versatile carrier system for in vitro and in vivo immune stimulation based on soft matter DNA nanoparticles (NPs). The incorporation of lipid-modified nucleotides into DNA strands enables the formation of micelles of uniform size. In a single self-assembly step, the micelles can be equipped with immune adjuvant (CpG) motifs and fluorescent probes. The immunological effects of CpG confined at the NP surface were studied in a comprehensive manner in animal experiments. Dose-dependent activation of spleen dendritic cells (DCs) by CpG-conjugated NP was observed, which was accompanied by the pronounced up-regulation of co-stimulatory molecule and cytokine production.


Assuntos
Ilhas de CpG/genética , DNA/administração & dosagem , DNA/genética , Células Dendríticas/imunologia , Lipídeos/química , Nanocápsulas/química , Baço/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/química , Animais , Células Cultivadas , Citocinas/imunologia , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Lipossomos/administração & dosagem , Lipossomos/química , Camundongos , Camundongos Endogâmicos C57BL , Baço/citologia , Baço/efeitos dos fármacos , Transfecção/métodos
10.
Bioconjug Chem ; 27(1): 36-41, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26619248

RESUMO

Photosynthesis is Nature's major process for converting solar into chemical energy. One of the key players in this process is the multiprotein complex photosystem I (PSI) that through absorption of incident photons enables electron transfer, which makes this protein attractive for applications in bioinspired photoactive hybrid materials. However, the efficiency of PSI is still limited by its poor absorption in the green part of the solar spectrum. Inspired by the existence of natural phycobilisome light-harvesting antennae, we have widened the absorption spectrum of PSI by covalent attachment of synthetic dyes to the protein backbone. Steady-state and time-resolved photoluminescence reveal that energy transfer occurs from these dyes to PSI. It is shown by oxygen-consumption measurements that subsequent charge generation is substantially enhanced under broad and narrow band excitation. Ultimately, surface photovoltage (SPV) experiments prove the enhanced activity of dye-modified PSI even in the solid state.


Assuntos
Corantes Fluorescentes/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Complexo de Proteína do Fotossistema I/química , Cianobactérias/química , Transferência de Energia , Transferência Ressonante de Energia de Fluorescência , Concentração de Íons de Hidrogênio , Luminescência , Lisina/química , Microscopia Eletrônica de Transmissão , Oxigênio/química , Oxigênio/metabolismo
11.
Chem Asian J ; 9(8): 2225-31, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24957252

RESUMO

Site-specific derivatization of chemically equivalent functional groups has recently been facilitated by the introduction of high-affinity aptamers as non-covalent protective groups. More specifically, a series of RNA aptamers have proven to be highly efficient in enhancing the regioselectivity of reactions with the aminoglycoside antibiotic neomycin B, which carries several chemically indistinguishable amino and hydroxy groups. Since small-molecule targets tend to exhibit multiple modes of binding with a single aptamer, the impact of secondary binding sites on the regioselectivity should be considered. To address this issue, we investigated a series of well-characterized RNA aptamers that bind neomycin B and propose a mechanism that accounts for the regioselective outcome of these transformations. We further demonstrate that the regioselectivity induced by non-covalent aptamer protective groups is determined by the number of binding sites, their affinity, and the mode of interaction with the guest molecule.


Assuntos
Aptâmeros de Nucleotídeos/química , Antibacterianos/química , Sequência de Bases , Sítios de Ligação , Framicetina/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
12.
Adv Mater ; 26(28): 4863-9, 2014 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-24862686

RESUMO

The large multiprotein complex, photosystem I (PSI), which is at the heart of light-dependent reactions in photosynthesis, is integrated as the active component in a solid-state organic photovoltaic cell. These experiments demonstrate that photoactive megadalton protein complexes are compatible with solution processing of organic-semiconductor materials and operate in a dry non-natural environment that is very different from the biological membrane.


Assuntos
Fontes de Energia Bioelétrica , Eletrodos , Complexo de Proteína do Fotossistema I/química , Complexo de Proteína do Fotossistema I/efeitos da radiação , Semicondutores , Energia Solar , Transdutores , Transferência de Energia/efeitos da radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais
13.
Biomacromolecules ; 15(6): 2019-26, 2014 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-24833130

RESUMO

This paper describes the synthesis and characterization of polymer-peptide conjugates to be used as infection-resistant coating for biomaterial implants and devices. Antiadhesive polymer brushes composed of block copolymer Pluronic F-127 (PF127) were functionalized with antimicrobial peptides (AMP), able to kill bacteria on contact, and arginine-glycine-aspartate (RGD) peptides to promote the adhesion and spreading of host tissue cells. The antiadhesive and antibacterial properties of the coating were investigated with three bacterial strains: Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. The ability of the coating to support mammalian cell growth was determined using human fibroblast cells. Coatings composed of the appropriate ratio of the functional components: PF127, PF127 modified with AMP, and PF127 modified with RGD showed good antiadhesive and bactericidal properties without hampering tissue compatibility.


Assuntos
Anti-Infecciosos/química , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Oligopeptídeos/química , Polímeros/química , Sequência de Aminoácidos , Anti-Infecciosos/farmacologia , Aderência Bacteriana/genética , Biofilmes/crescimento & desenvolvimento , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Dados de Sequência Molecular , Oligopeptídeos/genética , Oligopeptídeos/farmacologia , Polímeros/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/fisiologia , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia
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