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1.
Crit Care ; 28(1): 112, 2024 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582934

RESUMO

BACKGROUND: Approximately one in three survivors of critical illness suffers from intensive-care-unit-acquired weakness, which increases mortality and impairs quality of life. By counteracting immobilization, a known risk factor, active mobilization may mitigate its negative effects on patients. In this single-center trial, the effect of robotic-assisted early mobilization in the intensive care unit (ICU) on patients' outcomes was investigated. METHODS: We enrolled 16 adults scheduled for lung transplantation to receive 20 min of robotic-assisted mobilization and verticalization twice daily during their first week in the ICU (intervention group: IG). A control group (CG) of 13 conventionally mobilized patients after lung transplantation was recruited retrospectively. Outcome measures included the duration of mechanical ventilation, length of ICU stay, muscle parameters evaluated by ultrasound, and quality of life after three months. RESULTS: During the first week in the ICU, the intervention group received a median of 6 (interquartile range 3-8) robotic-assisted sessions of early mobilization and verticalization. There were no statistically significant differences in the duration of mechanical ventilation (IG: median 126 vs. CG: 78 h), length of ICU stay, muscle parameters evaluated by ultrasound, and quality of life after three months between the IG and CG. CONCLUSION: In this study, robotic-assisted mobilization was successfully implemented in the ICU setting. No significant differences in patients' outcomes were observed between conventional and robotic-assisted mobilization. However, randomized and larger studies are necessary to validate the adequacy of robotic mobilization in other cohorts. TRIAL REGISTRATION: This single-center interventional trial was registered in clinicaltrials.gov as NCT05071248 on 27/08/2021.


Assuntos
Deambulação Precoce , Procedimentos Cirúrgicos Robóticos , Adulto , Humanos , Estudos Retrospectivos , Qualidade de Vida , Estudos de Coortes , Estudos Prospectivos , Grupos Controle , Unidades de Terapia Intensiva , Respiração Artificial , Estado Terminal/terapia
2.
Chembiochem ; 24(5): e202200570, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36567253

RESUMO

The incorporation of photoswitches into the molecular structure of peptides and proteins enables their dynamic photocontrol in complex biological systems. Here, a perfluorinated azobenzene derivative triggered by amber light was site-specifically conjugated to cysteines in a helical peptide by perfluoroarylation chemistry. In response to the photoisomerization (trans→cis) of the conjugated azobenzene with amber light, the secondary structure of the peptide was modulated from a disorganized into an amphiphilic helical structure.


Assuntos
Âmbar , Peptídeos , Peptídeos/química , Proteínas , Estrutura Secundária de Proteína , Compostos Azo/química , Luz
3.
Phys Chem Chem Phys ; 25(6): 5037-5048, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36722915

RESUMO

The synthesis and detailed characterization of low-viscosity room-temperature ionic liquids (RTILs) and [BnPh3P]+ salts with the cyano(fluoro)borate anions [BF(CN)3]- (MFB), [BF2(CN)2]- (DFB), and [BF3(CN)]- as well as the new mixed-substituted anion [BFH(CN)2]- (FHB) is described. The RTILs with [EMIm]+ or [BMPL]+ as countercations were obtained in yields of up to 98% from readily available alkali metal salts and in high purities that allow application in electrochemical devices. Trends in thermal stability, melting and freezing behavior, density, electrochemical stability, dynamic viscosity, specific conductivity and ion diffusivity have been assessed and compared to those of the related tetracyanoborate- and cyano(hydrido)borate-RTILs. The crystal structure analysis of the [BnPh3P]+ salts of [BFn(CN)4-n]- (n = 0-4), [BHn(CN)4-n]- (n = 1-3) and [BFH(CN)2]- provided experimental access to anion volumina that together with ion molecular mass, electrostatic potential, shape and chemical stability have been correlated to physicochemical properties. In addition, the cytotoxicity of the [EMIm]+-ILs and potassium or sodium salts was studied.

4.
Arch Pharm (Weinheim) ; 356(2): e2200463, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36403201

RESUMO

Increasing resistance against antimycotic drugs challenges anti-infective therapies today and contributes to the mortality of infections by drug-resistant Candida species and strains. Therefore, novel antifungal agents are needed. A promising approach in developing new drugs is using naturally occurring molecules as lead structures. In this work, 4,4'-dihydroxyazobenzene, a compound structurally related to antifungal stilbene derivatives and present in Agaricus xanthodermus (yellow stainer), served as a starting point for the synthesis of five azobenzene derivatives. These compounds prevented the growth of both fluconazole-susceptible and fluconazole-resistant Candida albicans and Candida auris strains. Further in vivo studies are required to confirm the potential therapeutic value of these compounds.


Assuntos
Candida albicans , Fluconazol , Candida auris , Relação Estrutura-Atividade , Antifúngicos/química , Testes de Sensibilidade Microbiana
5.
BMC Nurs ; 22(1): 45, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36797701

RESUMO

BACKGROUND: Early mobilization can help reduce severe side effects such as muscle atrophy that occur during hospitalization. However, due to time and staff shortages in intensive and critical care as well as safety risks for patients, it is often difficult to adhere to the recommended therapy time of twenty minutes twice a day. New robotic technologies might be one approach to achieve early mobilization effectively for patients and also relieve users from physical effort. Nevertheless, currently there is a lack of knowledge regarding the factors that are important for integrating of these technologies into complex treatment settings like intensive care units or rehabilitation units. METHODS: European experts from science, technical development and end-users of robotic systems (n = 13) were interviewed using a semi-structured interview guideline to identify barriers and facilitating factors for the integration of robotic systems into daily clinical practice. They were asked about structural, personnel and environmental factors that had an impact on integration and how they had solved challenges. A latent content analysis was performed regarding the COREQ criteria. RESULTS: We found relevant factors regarding the development, introduction, and routine of the robotic system. In this context, costs, process adjustments, a lack of exemptions, and a lack of support from the manufacturers/developers were identified as challenges. Easy handling, joint decision making between the end-users and the decision makers in the hospital, an accurate process design and the joint development of the robotic system of end-users and technical experts were found to be facilitating factors. CONCLUSION: The integration and preparation for the integration of robotic assistance systems into the inpatient setting is a complex intervention that involves many parties. This study provides evidence for hospitals or manufacturers to simplify the planning of integrations for permanent use. TRIAL REGISTRATION: DRKS-ID: DRKS00023848; registered 10/12/2020.

6.
Chemistry ; 28(39): e202200786, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35621167

RESUMO

Flavonoids are polyphenolic natural products and have shown significant potential as disease-modifying agents against neurodegenerative disorders like Alzheimer's disease (AD), with activities even in vivo. Hybridization of the natural products taxifolin and silibinin with cinnamic acid led to an overadditive effect of these compounds in several phenotypic screening assays related to neurodegeneration and AD. Therefore, we have exchanged the flavonoid part of the hybrids with different flavonoids, which show higher efficacy than taxifolin or silibinin, to improve the activity of the respective hybrids. Chemical connection between the flavonoid and cinnamic acid was realized by an amide instead of a labile ester bond to improve stability towards hydrolysis. To investigate the influence of a double bond at the C-ring of the flavonoid, the dehydro analogues of the respective hybrids were also synthesized. All compounds obtained show neuroprotection against oxytosis, ferroptosis and ATP-depletion, respectively, in the murine hippocampal cell line HT22. Interestingly, the taxifolin and the quercetin derivatives are the most active compounds, whereby the quercetin derivate shows even more pronounced activity than the taxifolin one in all assays applied. As aimed for, no hydrolysis product was found in cellular uptake experiments after 4 h whereas different metabolites were detected. Furthermore, the quercetin-cinnamic acid amide showed pronounced activity in an in vivo AD mouse model at a remarkably low dose of 0.3 mg/kg.


Assuntos
Doença de Alzheimer , Produtos Biológicos , Doença de Alzheimer/tratamento farmacológico , Amidas , Animais , Cinamatos , Flavonoides/química , Flavonoides/farmacologia , Camundongos , Quercetina , Silibina
7.
Int J Mol Sci ; 22(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33802220

RESUMO

Metabolic glycoengineering enables a directed modification of cell surfaces by introducing target molecules to surface proteins displaying new features. Biochemical pathways involving glycans differ in dependence on the cell type; therefore, this technique should be tailored for the best results. We characterized metabolic glycoengineering in telomerase-immortalized human mesenchymal stromal cells (hMSC-TERT) as a model for primary hMSC, to investigate its applicability in TERT-modified cell lines. The metabolic incorporation of N-azidoacetylmannosamine (Ac4ManNAz) and N-alkyneacetylmannosamine (Ac4ManNAl) into the glycocalyx as a first step in the glycoengineering process revealed no adverse effects on cell viability or gene expression, and the in vitro multipotency (osteogenic and adipogenic differentiation potential) was maintained under these adapted culture conditions. In the second step, glycoengineered cells were modified with fluorescent dyes using Cu-mediated click chemistry. In these analyses, the two mannose derivatives showed superior incorporation efficiencies compared to glucose and galactose isomers. In time-dependent experiments, the incorporation of Ac4ManNAz was detectable for up to six days while Ac4ManNAl-derived metabolites were absent after two days. Taken together, these findings demonstrate the successful metabolic glycoengineering of immortalized hMSC resulting in transient cell surface modifications, and thus present a useful model to address different scientific questions regarding glycosylation processes in skeletal precursors.


Assuntos
Glicocálix , Hexosaminas , Células-Tronco Mesenquimais/metabolismo , Engenharia Metabólica , Modelos Biológicos , Mioblastos Esqueléticos/metabolismo , Linhagem Celular Transformada , Glicocálix/química , Glicocálix/metabolismo , Hexosaminas/química , Hexosaminas/metabolismo , Humanos
8.
Pharm Res ; 34(1): 58-72, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27628627

RESUMO

PURPOSE: The inhibition of myostatin - a member of the transforming growth factor (TGF-ß) family - drives regeneration of functional skeletal muscle tissue. We developed a bioresponsive drug delivery system (DDS) linking release of a myostatin inhibitor (MI) to inflammatory flares of myositis to provide self-regulated MI concentration gradients within tissues of need. METHODS: A protease cleavable linker (PCL) - responding to MMP upregulation - is attached to the MI and site-specifically immobilized on microparticle surfaces. RESULTS: The PCL disintegrated in a matrix metalloproteinase (MMP) 1, 8, and particularly MMP-9 concentration dependent manner, with MMP-9 being an effective surrogate biomarker correlating with the activity of myositis. The bioactivity of particle-surface bound as well as released MI was confirmed by luciferase suppression in stably transfected HEK293 cells responding to myostatin induced SMAD phosphorylation. CONCLUSIONS: We developed a MMP-responsive DDS for MI delivery responding to inflammatory flare of a diseased muscle matching the kinetics of MMP-9 upregulation, with MMP-9 kinetics matching (patho-) physiological myostatin levels. ᅟ: Graphical Abstract Schematic illustration of the matrix metalloproteinase responsive delivery system responding to inflammatory flares of muscle disease. The protease cleavable linker readily disintegrates upon entry into the diseased tissue, therby releasing the mystatin inhibitor.


Assuntos
Metaloproteinases da Matriz/metabolismo , Miostatina/antagonistas & inibidores , Preparações Farmacêuticas/administração & dosagem , Inibidores de Proteases/administração & dosagem , Animais , Biomarcadores/metabolismo , Linhagem Celular , Sistemas de Liberação de Medicamentos/métodos , Células HEK293 , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Miosite/tratamento farmacológico , Miosite/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/efeitos dos fármacos
9.
Chembiochem ; 17(9): 866-75, 2016 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-26818821

RESUMO

Bio-orthogonal copper (I)-catalyzed azide-alkyne cycloaddition (CuAAC) has been widely used to modify azide- or alkyne-bearing monosaccharides on metabolic glyco-engineered mammalian cells. Here, we present a systematic study to elucidate the design space for the cytotoxic effects of the copper catalyst on NIH 3T3 fibroblasts and on HEK 293-F cells. Monitoring membrane integrity by flow cytometry and RT-PCR analysis with apoptotic and anti-apoptotic markers elucidated the general feasibility of CuAAC, with exposure time of the CuAAC reaction mixture having the major influence on biocompatibility. A high labeling efficiency of HEK 293-F cells with a fluorescent alkyne dye was rapidly achieved by CuAAC in comparison to copper free strain-promoted azide-alkyne cycloaddition (SPAAC). The study details effective and biocompatible conditions for CuAAC-based modification of glyco-engineered cells in comparison to its copper free alternative.


Assuntos
Alcinos/química , Azidas/química , Materiais Biocompatíveis/química , Glicoproteínas de Membrana/química , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Materiais Biocompatíveis/toxicidade , Catálise , Sobrevivência Celular/efeitos dos fármacos , Química Click , Cobre , Reação de Cicloadição , Fluoresceínas/química , Fluoresceínas/toxicidade , Células HEK293 , Humanos , Peróxido de Hidrogênio/metabolismo , Glicoproteínas de Membrana/metabolismo , Camundongos , Microscopia de Fluorescência , Células NIH 3T3 , Propídio/química , Propídio/toxicidade
10.
Chemistry ; 22(41): 14701-6, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27627995

RESUMO

Three water-soluble tetracationic quadrupolar chromophores comprising two three-coordinate boron π-acceptor groups bridged by thiophene-containing moieties were synthesised for biological imaging applications. Compound 3 containing the bulkier 5-(3,5-Me2 C6 H2 )-2,2'-(C4 H2 S)2 -5'-(3,5-Me2 C6 H2 ) bridge is stable over a long period of time, exhibits a high fluorescence quantum yield and strong one- and two-photon absorption (TPA), and has a TPA cross section of 268 GM at 800 nm in water. Confocal laser scanning fluorescence microscopy studies in live cells indicated localisation of the chromophore at the mitochondria; moreover, cytotoxicity measurements proved biocompatibility. Thus, chromophore 3 has excellent potential for one- and two-photon-excited fluorescence imaging of mitochondrial function in cells.


Assuntos
Boranos/síntese química , Corantes Fluorescentes/química , Mitocôndrias/metabolismo , Fluorescência , Células HEK293 , Células Hep G2 , Humanos , Microscopia de Fluorescência , Imagem Molecular/métodos , Estrutura Molecular , Imagem Óptica , Solubilidade , Relação Estrutura-Atividade , Tiofenos/química , Água
11.
ACS Biomater Sci Eng ; 10(1): 149-155, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37296497

RESUMO

Vascular endothelial growth factor A-165 (VEGF-A165) positively modulates neointimal hyperplasia, lumen stenosis, and neovascularization. One challenge for the use of VEGF-A165 for potential therapy is its short serum half-life. Therefore, we are designing VEGF-A165 bioconjugates carrying polyethylene glycol (PEG). The purity of the recombinantly expressed human VEGF-A165 exceeded 90%. The growth factor had a half-maximal effective concentration of 0.9 ng/mL (EC50) and induced tube formation of human umbilical vein endothelial cells. PEGylation was conducted by Schiff base reaction followed by reductive amination. After purification, two species were obtained, with one or two PEG attached per VEGF-A165 dimer. Both resulting bioconjugates had a purity exceeding 90%, wild-type bioactivity, and increased hydrodynamic radii as required for prolonging the half-life.


Assuntos
Neovascularização Patológica , Fator A de Crescimento do Endotélio Vascular , Humanos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Fator A de Crescimento do Endotélio Vascular/química , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
ACS Biomater Sci Eng ; 10(1): 156-165, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37988287

RESUMO

Attachment of polyethylene glycol (PEG) chains is a common, well-studied, and Food and Drug Administration-approved method to address the pharmacokinetic challenges of therapeutic proteins. Occasionally, PEGylation impairs the activity of pharmacodynamics (PD). To overcome this problem, disease-relevant cleavable linkers between the polymer and the therapeutic protein can unleash full PD by de-PEGylating the protein at its target site. In this study, we engineered a matrix metalloproteinase (MMP)-responsive fibroblast growth factor 2 (FGF-2) mutant that was site-specifically extended with a PEG polymer chain. Using bioinspired strategies, the bioconjugate was designed to release the native protein at the desired structure/environment with preservation of the proliferative capacity in vitro on NIH3T3 cells. In vivo, hepatic exposure was diminished but not its renal distribution over time compared to unconjugated FGF-2. By releasing the growth factor from the PEG polymer in response to MMP cleavage, restored FGF-2 may enter hard-to-reach tissues and activate cell surface receptors or nuclear targets.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Proteínas , Estados Unidos , Camundongos , Animais , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células NIH 3T3 , Polietilenoglicóis/farmacologia , Metaloproteinases da Matriz
13.
Eur J Pharm Biopharm ; 203: 114462, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39197542

RESUMO

Nature realizes protein and peptide depots by catalyzing covalent bonds with the extracellular matrix (ECM) of tissues. We are translating this natural blueprint for the sustained delivery of a myostatin-inhibiting peptide (Anti-Myo), resulting in an enzyme depot established from injectable solutions. For that, we fused Anti-Myo to the D-domain of insulin-like growth factor I, a transglutaminase (TG) substrate. TG catalyzed the covalent binding of the D-domain to ECM proteins, such as laminin and fibronectin, on bioengineered ECM and in mice. ECM decorated with Anti-Myo suppressed myostatin activity and pathway activation and reduced the differentiation of preconditioned bone marrow-derived macrophages into osteoclasts in vitro.


Assuntos
Miostatina , Transglutaminases , Transglutaminases/metabolismo , Animais , Camundongos , Miostatina/metabolismo , Matriz Extracelular/metabolismo , Peptídeos/química , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/administração & dosagem , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Humanos , Preparações de Ação Retardada , Camundongos Endogâmicos C57BL
14.
ACS Biomater Sci Eng ; 10(6): 3825-3832, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38722049

RESUMO

In recent years, a novel treatment method for cancer has emerged, which is based on the starvation of tumors of amino acids like arginine. The deprivation of arginine in serum is based on enzymatic degradation and can be realized by arginine deaminases like the l-amino acid oxidase found in the ink toxin of the sea hare Aplysia punctata. Previously isolated from the ink, the l-amino acid oxidase was described to oxidate the essential amino acids l-lysine and l-arginine to their corresponding deaminated alpha-keto acids. Here, we present the recombinant production and functionalization of the amino acid oxidase Aplysia punctata ink toxin (APIT). PEGylated APIT (APIT-PEG) increased the blood circulation time. APIT-PEG treatment of patient-derived xenografted mice shows a significant dose-dependent reduction of tumor growth over time mediated by amino acid starvation of the tumor. Treatment of mice with APIT-PEG, which led to deprivation of arginine, was well tolerated.


Assuntos
Aplysia , Arginina , Lisina , Polietilenoglicóis , Animais , Arginina/farmacologia , Arginina/química , Lisina/farmacologia , Lisina/química , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto , Toxinas Marinhas/farmacologia , Toxinas Marinhas/uso terapêutico , Toxinas Marinhas/química , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , L-Aminoácido Oxidase/farmacologia , L-Aminoácido Oxidase/metabolismo , L-Aminoácido Oxidase/química , Feminino , Linhagem Celular Tumoral
15.
Int J Nurs Stud ; 152: 104702, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350342

RESUMO

BACKGROUND: Early mobilization is only carried out to a limited extent in the intensive care unit. To address this issue, the robotic assistance system VEMOTION® was developed to facilitate (early) mobilization measures more easily. This paper describes the first integration of robotic assistance systems in acute clinical intensive care units. OBJECTIVE: Feasibility test of robotic assistance in early mobilization of intensive care patients in routine clinical practice. SETTING: Two intensive care units guided by anesthesiology at a German university hospital. PARTICIPANTS: Patients who underwent elective surgery with postoperative treatment in the intensive care unit and had an estimated ventilation time over 48 h. METHODS: Participants underwent robot-assisted mobilization, scheduled for twenty-minute sessions twice a day, ten times or one week, conducted by nursing staff under actual operational conditions on the units. No randomization or blinding took place. We assessed data regarding feasible cutoff points (in brackets): the possibility of enrollment (x ≥ 50 %), duration (pre- and post-setup (x ≤ 25 min), therapy duration (x = 20 min), and intervention-related parameters (number of mobilizing professionals (x ≤ 2), intensity of training, events that led to adverse events, errors or discontinuation). Mobilizing professionals rated each mobilization regarding their physical stress (x ≤ 3) and feasibility (x ≥ 4) on a 7 Point Likert Scale. An estimated sample size of at least twenty patients was calculated. We analyzed the data descriptively. RESULTS: Within 6 months, we screened thirty-two patients for enrollment. 23 patients were included in the study and 16 underwent mobilization using robotic assistance, 7 dropped out (enrollment eligibility = 69 %). On average, 1.9 nurses were involved per therapy unit. Participants received 5.6 robot-assisted mobilizations in mean. Pre- and post-setup had a mean duration of 18 min, therapy a mean of 21 min. The robot-assisted mobilization was started after a median of 18 h after admission to the intensive care unit. We documented two adverse events (pain), twelve errors in handling, and seven unexpected events that led to interruptions or discontinuation. No serious adverse events occurred. The mobilizing nurses rated their physical stress as low (mean 2.0 ±â€¯1.3) and the intervention as feasible (mean 5.3 ±â€¯1.6). CONCLUSIONS: Robot-assisted mobilization was feasible, but specific safety measures should be implemented to prevent errors. Robotic-assisted mobilization requires process adjustments and consideration of unit staffing levels, as the intervention does not save staff resources or time. REGISTRATION: clinicaltrials.org TRN: NCT05071248; Date: 2021/10/08; URL https://clinicaltrials.gov/ct2/show/NCT05071248. TWEETABLE ABSTRACT: Robot-assisted early mobilization in intensive care patients is feasible and no adverse event occurred.


Assuntos
Deambulação Precoce , Robótica , Humanos , Estudos de Viabilidade , Cuidados Críticos , Unidades de Terapia Intensiva
16.
Eur J Pharm Biopharm ; 192: 79-87, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37783360

RESUMO

Tissue-type plasminogen activator (tPA) is the gold standard for emergency treatment of ischemic stroke, which is the third leading cause of death worldwide. Major challenges of tPA therapy are its rapid elimination by plasminogen activator inhibitor-1 (PAI-1) and hepatic clearance, leading to the use of high doses and consequent serious side effects, including internal bleeding, swelling and low blood pressure. In this regard, we developed three polyethylene glycol (PEG)ylated tPA bioconjugates based on the recombinant human tPA drug Alteplase using site-specific conjugation strategies. The first bioconjugate with PEGylation at the N-terminus of tPA performed by reductive alkylation showed a reduced proteolytic activity of 68 % compared to wild type tPA. PEGylation at the single-free cysteine of tPA with linear and branched PEG revealed similar proteolytic activities as the wild-type protein. Moreover, both bioconjugates with PEG-cysteine-modification showed 2-fold slower inhibition kinetics by PAI-1. All bioconjugates increased in hydrodynamic size as a critical requirement for half-life extension.


Assuntos
Inibidor 1 de Ativador de Plasminogênio , Ativador de Plasminogênio Tecidual , Humanos , Ativador de Plasminogênio Tecidual/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Cisteína
17.
Front Neurol ; 14: 1069381, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745669

RESUMO

Background: Complex Regional Pain Syndrome (CRPS) is a severe pain disorder that does not yet have a specific treatment. Patients with CRPS not only suffer from a wide range of symptoms that affect their quality of life but also present psychological affections to the way they see their body and specifically their affected limb. Virtual Reality (VR) modalities have become a targeted treatment for chronic pain and in the case of CRPS, may be a valuable approach to the mechanisms that affect these patients. Objectives: Using the PRISMA Scoping Review guidelines, we intend to uncover the key information from the studies available about VR modalities in the treatment of CRPS. We focus on the improvement of pain levels, body perception disturbances (BPD), and limb movement/daily function. Results: Our search strategy resulted in 217 articles from PubMed. Twenty were assessed for eligibility and seven were included in the final qualitative synthesis. Of these seven articles, we included a clinical trial, three pilot studies, a blinded randomized controlled trial, a crossover double-blind trial, and a randomized controlled trial. These studies provide important subjective patient findings, along with some statistically significant results in the experiences of VR therapies modulating pain, BPD, and improving limb movement/daily function. However, not all the studies included statistical analysis, and there are contradicting data found from some patients that did not perceive any improvement from VR therapies. Conclusions: We describe the results found in 7 articles that focus on the treatment of CRPS with VR modalities. Overall, the articles have various limitations, but the strategies related to immersive virtual reality, cardiac signaling, body switching and limb modulation have shown the most promising results for pain reduction and BPD improvement. These strategies reflect on pathophysiological mechanisms that are hypothesized to be affected in CRPS patients leading to the chronic pain and BPD that they experience. Not much evidence was found for improvement in limb movement and daily function. This review is a pathway for future studies on this topic and a more extensive data synthesis when more information is available.

18.
ACS Biomater Sci Eng ; 9(6): 2937-2948, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-36444758

RESUMO

Carbon monoxide (CO) is a therapeutic gas with therapeutic potential in intestinal bowel disease. Therapeutic efficacy in the gastrointestinal tract (GIT) must be paired with safe and convenient use. Therefore, we designed an oral CO releasing system (OCORS) pairing tunable CO release into the GIT while preventing the release of any other molecule from within the device, causing safety concerns. The dimensions of the device, which is manufactured from 3D printed components, are within compendial limits. This is achieved by controlling CO decarbonylation from a molybdenum complex with a FeCl3 solution. OCORS' surrounding silicon membranes control release rates, as does the loading with carbonylated molybdenum complex and FeCl3 solution. Herein we describe the development of the system, the characterization of the CO releasing molecule (CORM), and the CO release kinetics of the overall system. Neither the CORM nor isocyanoacetate as a potential reaction byproduct were cytotoxic. Finally, we demonstrated by design validation in an in vivo porcine model that, except for the release of the therapeutic CO, OCORS isolates all components during transit through the stomach. We could show that OCORS generated and released CO locally into the stomach of the animals without systemic exposure, measured as the carboxyhemoglobin content in the blood of the pigs. In conclusion, OCORS derisks oral development by limiting patient exposure to (desirable) CO while preventing contact with any further (undesirable) chemical, by-, or degradation products. CO generating devices come in reach, which now can be used by anyone, anywhere, and anytime.


Assuntos
Monóxido de Carbono , Molibdênio , Animais , Suínos , Monóxido de Carbono/uso terapêutico , Monóxido de Carbono/metabolismo
19.
ACS Biomater Sci Eng ; 8(6): 2220-2231, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35610572

RESUMO

Intraoperative bleeding and postoperative bleeding are major surgical complications. Tissue sealants, hemostats, and adhesives provide the armamentarium for establishing hemostatic balance, including the tissue sealant fibrin. Fibrin sealants combine advantages including instantaneous effect, biocompatibility, and biodegradability. However, several challenges remain. This review summarizes current fibrin product generations and highlights new trends and potential strategies for future improvement.


Assuntos
Adesivo Tecidual de Fibrina , Hemostáticos , Fibrina , Adesivo Tecidual de Fibrina/uso terapêutico , Hemostasia Cirúrgica , Hemostáticos/farmacologia , Hemostáticos/uso terapêutico
20.
J Control Release ; 347: 115-126, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35489547

RESUMO

3D printing of biomaterials enables spatial control of drug incorporation during automated manufacturing. This study links bioresponsive release of the anabolic biologic, insulin-like growth factor-I (IGF-I) in response to matrix metalloproteinases (MMP) to 3D printing using the block copolymer of poly(2-methyl-2-oxazoline) and thermoresponsive poly(2-n-propyl-2-oxazine) (POx-b-POzi). For that, a chemo-enzymatic synthesis was deployed, ligating IGF-I enzymatically to a protease sensitive linker (PSL), which was conjugated to a POx-b-POzi copolymer. The product was blended with the plain thermogelling POx-b-POzi hydrogel. MMP exposure of the resulting hydrogel triggered bioactive IGF-I release. The bioresponsive IGF-I containing POx-b-POzi hydrogel system was further detailed for shape control and localized incorporation of IGF-I via extrusion 3D printing for future applications in biomedicine and biofabrication.


Assuntos
Hidrogéis , Fator de Crescimento Insulin-Like I , Materiais Biocompatíveis/metabolismo , Hidrogéis/metabolismo , Metaloproteinases da Matriz/metabolismo , Polímeros , Impressão Tridimensional
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