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1.
J Wound Care ; 29(1): 18-26, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31930942

RESUMO

OBJECTIVE: Incontinence-associated dermatitis (IAD) is a common type of irritant contact dermatitis. It is categorised by persistent erythema and can be associated with denudation and/or colonisation and infection. IAD is challenging to treat and affects 3.4-50% of patients. This case series evaluates a novel, elastomeric, advanced skin protectant (3M Cavilon Advanced Skin Protectant) in a UK acute health-care setting, for the management of IAD in patients suffering from moisture-associated skin damage (MASD) in the sacral/genital area. METHOD: The patient's skin was assessed by clinicians using the GLOBIAD classification tool at the point of recruitment and to monitor progress throughout the study period. The product was applied as a single layer in accordance with the instructions for use. Patients, when able, were asked to assess their own pain level using the Wong-Baker FACES pain scale. Photographs were taken as part of the ongoing assessment. RESULTS: The skin protectant was used on average every 2.28 days. Of the 18 IAD patients recruited, 79% (n=11) were classified as IAD-free, based on the GLOBIAD categorisation tool, by the end of the evaluation period. Skin deterioration during the evaluation period was seen in one patient (6%), and of the patients able to complete pain assessments, 55% (n=6) reported a reduction in pain. CONCLUSION: These results suggest that the elastomeric skin protectant, applied every three days, plays a role in the improvement of IAD. The skin protectant adheres to wet and weeping partial-thickness wounds and may aid IAD management. Reducing application to every third day supports a change in practice which may offer benefits to patients and caregivers.


Assuntos
Cianoacrilatos/administração & dosagem , Dermatite Irritante/terapia , Elastômeros/administração & dosagem , Incontinência Fecal/complicações , Substâncias Protetoras/administração & dosagem , Incontinência Urinária/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Nádegas , Dermatite Irritante/etiologia , Dermatite Irritante/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/lesões , Higiene da Pele/métodos
2.
BMC Anesthesiol ; 16: 78, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27619387

RESUMO

BACKGROUND: The use of elastomeric devices for ambulatory intravenous pain treatment in Major Ambulatory Surgery (MAS) has been described to improve postoperative pain management. The objective of the study was to describe the first 3 years experience of the use of elastomeric devices for ambulatory intravenous pain treatment in MAS implemented at our site since 2010. METHODS: Data were retrieved from the medical records for all patients who, between January 2010 and March 2014, underwent surgical procedures at the ambulatory surgical centre at our hospital and were prescribed a home-based continuous intravenous analgesia. RESULTS: Data were retrieved from the medical records of 1128 patients. The most frequent surgical interventions included orthopedic and proctology surgeries. 80 % of patients were discharged home without pain; during the first 48 h after discharge roughly 40 % of subjects were completely free of pain, 50 % reported mild pain (VAS 1 to 3) and 9 % reported higher pain scores (4 and above). Peripheral nerve block was associated to better pain control in the immediate postoperative period. Vomiting in the first 24 h was 4.6 % before introducing haloperidol into the drug schemes, and 2.6 % thereafter. Complications related with the intravenous route required treatment withdrawal in 1.1 % cases. Only 3.5 % of patients returned to the hospital in the first 72 h, mainly for non-pain related reasons. Overall, 99.5 % of patients were satisfied with the treatment received at home. CONCLUSION: Our initial experience suggest that outpatient multimodal intravenous analgesia in patients undergoing day-case surgery is a feasible alternative in our setting, that allows an effective management of postoperative pain with a small rate of adverse events and complications requiring readmission.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/métodos , Analgésicos/administração & dosagem , Analgésicos/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Administração Intravenosa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Analgésicos/efeitos adversos , Elastômeros/administração & dosagem , Feminino , Humanos , Bombas de Infusão , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Manejo da Dor/métodos , Satisfação do Paciente , Estudos Retrospectivos , Adulto Jovem
3.
Ann Pharm Fr ; 73(5): 378-90, 2015 Sep.
Artigo em Francês | MEDLINE | ID: mdl-25721763

RESUMO

INTRODUCTION: Within the cystic fibrosis patients' home care, EMERAA network ("Together against Cystic fibrosis in Rhone-Alpes and Auvergne") organizes parenteral antibiotics cures at home prepared in elastomeric infusion devices by hospital pharmacies. However, patients and nurses found that the durations of infusion with these devices were often longer than the nominal duration of infusion indicated by their manufacturer. This study aimed to identify the potential different causes in relation to these discordances. MATERIAL AND METHODS: Three hundred and ninety devices of two different manufacturers are tested in different experimental conditions: three antibiotics each at two different doses, duration of cold storage (three days or seven days) or immediate tests without cold storage, preparation and storage of the solution in the device (protocol Device) or transfer in the device just before measurement (protocol Pocket). RESULTS: All tests highlighted a longer flow duration for devices prepared according to the protocol Device versus the protocol Pocket (P=0.004). Flow duration is increased in the case of high doses of antibiotics with high viscosity such as piperacilline/tazobactam. DISCUSSION: The results of this in vitro study showed the impact of: (1) the time between the filling of the device and the flow of the solution; (2) cold storage of elastomeric infusion devices; (3) concentration of antibiotics and therefore the viscosity of the solution to infuse. CONCLUSION: It is therefore essential that health care teams are aware of factors, which may lead to longer infusion durations with these infusion devices. When the additional time for infusion remain acceptable, it should be necessary to inform the patient and to relativize these lengthening compared to many benefits that these devices provide for home care.


Assuntos
Antibacterianos/análise , Temperatura Baixa , Armazenamento de Medicamentos , Elastômeros/administração & dosagem , Análise de Injeção de Fluxo , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Fibrose Cística/tratamento farmacológico , Estabilidade de Medicamentos , Armazenamento de Medicamentos/métodos , Bombas de Infusão , Soluções Farmacêuticas
4.
Drug Dev Ind Pharm ; 40(2): 211-21, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23327358

RESUMO

OBJECTIVE: To design and evaluate a novel pressure sensitive adhesive (PSA) patch containing traditional Chinese medicine (TCM) using styrene-isoprene-styrene (SIS) copolymer. METHOD: A mixture D-optimal design with ternary response surface diagram was employed in the optimization process. The proportions of SIS copolymer, tackifying resin and plasticizer were selected as the independent variables while tack force, peel strength of the patch and skin penetrability of methyl salicylate were selected as the dependent variables. The optimized patch was then evaluated including in vivo absorption, pharmacological activities and skin irritation, by comparing with a commercial patch based on natural rubber. RESULTS: The optimized patch, which comprised 30.0% SIS copolymer, 26.6% tackifying resin and 43.4% plasticizer, was superior to commercial patch in skin permeation, pharmacological activities and skin biocompatibility. CONCLUSION: SIS copolymer was a suitable substitute to natural rubber in producing patches containing TCM formula.


Assuntos
Butadienos/química , Desenho de Fármacos , Medicamentos de Ervas Chinesas/química , Elastômeros/química , Hemiterpenos/química , Pentanos/química , Estireno/química , Adesivo Transdérmico , Animais , Butadienos/administração & dosagem , Avaliação Pré-Clínica de Medicamentos/métodos , Medicamentos de Ervas Chinesas/administração & dosagem , Elastômeros/administração & dosagem , Cobaias , Hemiterpenos/administração & dosagem , Masculino , Medicina Tradicional Chinesa/métodos , Camundongos , Camundongos Pelados , Técnicas de Cultura de Órgãos , Pentanos/administração & dosagem , Ratos , Ratos Wistar , Absorção Cutânea/efeitos dos fármacos , Absorção Cutânea/fisiologia , Estireno/administração & dosagem
5.
Bioconjug Chem ; 23(5): 958-65, 2012 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-22463082

RESUMO

Polymersomes, self-assembled from the block copolymer polybutadiene-block-poly(ethylene glycol), were prepared with well-defined diameters between 90 and 250 nm. The presence of ~1% of diethylene triamine penta acetic acid on the polymersome periphery allowed to chelate radioactive (111)In onto the surface and determine the biodistribution in mice as a function of both the polymersome size and poly(ethylene glycol) corona thickness (i.e., PEG molecular weight). Doubling the PEG molecular weight from 1 kg/mol to 2 kg/mol did not change the blood circulation half-life significantly. However, the size of the different polymersome samples did have a drastic effect on the blood circulation times. It was found that polymersomes of 120 nm and larger become mostly cleared from the blood within 4 h, presumably due to recognition by the reticuloendothelial system. In contrast, smaller polymersomes of around 90 nm circulated much longer. After 24 h more than 30% of the injected dose was still present in the blood pool. This sharp transition in blood circulation kinetics due to size is much more abrupt than observed for liposomes and was additionally visualized by SPECT/CT imaging. These findings should be considered in the formulation and design of polymersomes for biomedical applications. Size, much more than for liposomes, will influence the pharmacokinetics, and therefore, long circulating preparations should be well below 100 nm.


Assuntos
Butadienos/farmacocinética , Elastômeros/farmacocinética , Polietilenoglicóis/farmacocinética , Animais , Butadienos/administração & dosagem , Butadienos/química , Elastômeros/administração & dosagem , Elastômeros/química , Radioisótopos de Índio/análise , Lipossomos/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único
6.
Pharm Res ; 28(6): 1282-93, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21347565

RESUMO

PURPOSE: Biodegradable elastomers, which can possess favorable mechanical properties and degradation rates for soft tissue engineering applications, are more recently being explored as depots for biomolecule delivery. The objective of this study was to synthesize and process biodegradable, elastomeric poly(ester urethane)urea (PEUU) scaffolds and to characterize their ability to incorporate and release bioactive insulin-like growth factor-1 (IGF-1) and hepatocyte growth factor (HGF). METHODS: Porous PEUU scaffolds made from either 5 or 8 wt% PEUU were prepared with direct growth-factor incorporation. Long-term in vitro IGF-1 release kinetics were investigated in saline or saline with 100 units/ml lipase to simulate in vivo degradation. Cellular assays were used to confirm released IGF-1 and HGF bioactivity. RESULTS: IGF-1 release into saline occurred in a complex multi-phasic manner for up to 440 days. Scaffolds generated from 5 wt% PEUU delivered protein faster than 8 wt% scaffolds. Lipase-accelerated scaffold degradation led to delivery of >90% protein over 9 weeks for both polymer concentrations. IGF-1 and HGF bioactivity in the first 3 weeks was confirmed. CONCLUSIONS: The capacity of a biodegradable elastomeric scaffold to provide long-term growth-factor delivery was demonstrated. Such a system might provide functional benefit in cardiovascular and other soft tissue engineering applications.


Assuntos
Fator de Crescimento de Hepatócito/administração & dosagem , Fator de Crescimento Insulin-Like I/administração & dosagem , Poliésteres/administração & dosagem , Engenharia Tecidual/métodos , Implantes Absorvíveis , Animais , Células 3T3 BALB , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/síntese química , Linhagem Celular , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Elastômeros/administração & dosagem , Elastômeros/síntese química , Humanos , Camundongos , Poliésteres/síntese química
7.
Nat Commun ; 12(1): 3961, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34172721

RESUMO

Current materials used in biomedical devices do not match tissue's mechanical properties and leach various chemicals into the body. These deficiencies pose significant health risks that are further exacerbated by invasive implantation procedures. Herein, we leverage the brush-like polymer architecture to design and administer minimally invasive injectable elastomers that cure in vivo into leachable-free implants with mechanical properties matching the surrounding tissue. This strategy allows tuning curing time from minutes to hours, which empowers a broad range of biomedical applications from rapid wound sealing to time-intensive reconstructive surgery. These injectable elastomers support in vitro cell proliferation, while also demonstrating in vivo implant integrity with a mild inflammatory response and minimal fibrotic encapsulation.


Assuntos
Materiais Biomiméticos/administração & dosagem , Elastômeros/administração & dosagem , Procedimentos de Cirurgia Plástica/métodos , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Proliferação de Células/efeitos dos fármacos , Elastômeros/química , Elastômeros/farmacologia , Géis , Injeções , Camundongos , Polímeros/administração & dosagem , Polímeros/química , Polímeros/farmacologia , Ratos , Fatores de Tempo
8.
J Vasc Surg ; 52(1): 152-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20347548

RESUMO

PURPOSE: One of the major concerns in the long-term success of endovascular aneurysm repair (EVAR) is stent graft migration, which can cause type I endoleak and even aneurysm rupture. Fixation depends on the mechanical forces between the graft and both the aortic neck and the blood flow. Therefore, there are anatomical restrictions for EVAR, such as short and angulated necks. To improve the fixation of EVAR grafts, elastomer (PDMS) can be injected in the aneurysm sac. The support given by the elastomer might prevent dislocation and migration of the graft. The aim of this study was to measure the influence of an injectable biocompatible elastomer on the fixation strength of different EVAR grafts in an in vitro model. METHODS: The proximal part of three different stent grafts was inserted in a bovine artery with an attached latex aneurysm. The graft was connected to a tensile testing machine, applying force to the proximal fixation, while the artery with the aneurysm was fixated to the setup. The force to obtain graft dislodgement (DF) from the aorta was recorded in Newtons (N). Three different proximal seal lengths (5, 10, and 15 mm) were evaluated. The experiments were repeated after the space between the graft and the latex aneurysm was filled with the elastomer. Independent sample ttests were used for the comparison between the DF before and after elastomer treatment for each seal length. RESULTS: The mean DF (mean +/- SD) of all grafts without elastomer sac filling for a proximal seal length of 5, 10, and 15 mm were respectively, 4.4 +/- 3.1 N, 12.2 +/- 10.6 N, and 15.1 +/- 6.9 N. After elastomer sac filling, the dislodgement forces increased significantly (P < .001) to 20.9 +/- 3.8 N, 31.8 +/- 9.8 N, and 36.0 +/- 14.1 N, respectively. CONCLUSIONS: The present study shows that aneurysm sac filling may have a role as an adjuvant procedure to the present EVAR technique. The strength of the proximal fixation of three different stent grafts increases significantly in this in vitro setting. Further in vivo research must be done to see if this could facilitate the treatment of aneurysms with short infrarenal necks.


Assuntos
Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Materiais Biocompatíveis , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Elastômeros/administração & dosagem , Migração de Corpo Estranho/prevenção & controle , Stents , Animais , Implante de Prótese Vascular/efeitos adversos , Bovinos , Migração de Corpo Estranho/etiologia , Injeções , Teste de Materiais , Desenho de Prótese , Estresse Mecânico , Resistência à Tração
9.
J Pharm Sci ; 97(2): 860-74, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17701973

RESUMO

Numerous peptide drugs require continuous and local delivery to obtain optimum therapeutic effect. Herein, we describe the incorporation of a model peptide drug, vitamin B12, as well as goserelin acetate, in biodegradable elastomer cylinders through photo-cross-linking. The elastomer was prepared from acrylated star-poly(epsilon-caprolactone-co-D,L-lactide). Release was manipulated through the incorporation of poly(ethylene glycol) diacrylate (PEGD) into the network at concentrations up to 30% (w/w). The PEGD in the network caused rapid swelling that remained constant throughout the release period. The degree of swelling was low, ranging from 10 to 45% (w/w), and increasing as the PEGD content increased. Release proceeded with a minimal initial burst, and extended periods of nearly constant release, ranging from approximately 5 to 70% mass fraction released, were obtained. The release rate was independent of particle size and increased as the cylinder diameter decreased, as the amount of PEGD increased, as the molecular weight of PEGD increased, and as the agent loading increased. Moreover, goserelin acetate, which has a comparable diffusivity but greater aqueous solubility, was released at a greater rate than vitamin B12. This release behavior is explained as a balance between agent dissolution in the swollen polymer matrix and diffusion through the polymer matrix bulk.


Assuntos
Elastômeros/administração & dosagem , Gosserrelina/administração & dosagem , Polietilenoglicóis/administração & dosagem , Vitamina B 12/administração & dosagem , Biodegradação Ambiental , Reagentes de Ligações Cruzadas , Preparações de Ação Retardada , Gosserrelina/química , Peso Molecular , Solubilidade , Vitamina B 12/química
10.
J Biomater Appl ; 32(8): 1049-1062, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29298552

RESUMO

The effect of electron beam radiation on ethylene-propylene diene terpolymer/polypropylene blends is studied as an attempt to develop radiation sterilizable polypropylene/ethylene-propylene diene terpolymer blends suitable for medical devices. The polypropylene/ethylene-propylene diene terpolymer blends with mixing ratios of 80/20, 50/50, 20/80 were prepared in an internal mixer at 165°C and a rotor speed of 50 rpm/min followed by compression molding. The blends and the individual components were radiated using 3.0 MeV electron beam accelerator at doses ranging from 0 to 100 kGy in air and room temperature. All the samples were tested for tensile strength, elongation at break, hardness, impact strength, and morphological properties. After exposing to 25 and 100 kGy radiation doses, 50% PP blend was selected for in vivo studies. Results revealed that radiation-induced crosslinking is dominating in EPDM dominant blends, while radiation-induced degradation is prevailing in PP dominant blends. The 20% PP blend was found to be most compatible for 20-60 kGy radiation sterilization. The retention in impact strength with enhanced tensile strength of 20% PP blend at 20-60 kGy believed to be associated with increased compatibility between PP and EPDM along with the radiation-induced crosslinking. The scanning electron micrographs of the fracture surfaces of the PP/EPDM blends showed evidences consistent with the above contentation. The in vivo studies provide an instinct that the radiated blends are safe to be used for healthcare devices.


Assuntos
Materiais Biocompatíveis/química , Elastômeros/química , Etilenos/química , Polipropilenos/química , Animais , Materiais Biocompatíveis/administração & dosagem , Elastômeros/administração & dosagem , Elétrons , Etilenos/administração & dosagem , Raios gama , Dureza , Camundongos , Polipropilenos/administração & dosagem , Esterilização , Temperatura , Resistência à Tração
11.
J Orthop Surg Res ; 13(1): 251, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30305126

RESUMO

BACKGROUND: Pedicle screws can be augmented with polymethylmethacrylate (PMMA) cement through cannulated and fenestrated pedicle screws to improve screw anchorage. To overcome the drawbacks of PMMA, a modified augmentation technique applying a self-curing elastomeric material into a balloon-created cavity prior to screw insertion was developed and evaluated. The aim of the study was to compare the effect of the established and novel augmentation technique on pedicle screw anchorage in a biomechanical in vitro experiment. METHODS: In ten lumbar vertebral bodies, the right pedicles were instrumented with monoaxial cannulated and fenestrated pedicle screws and augmented in situ with 2 ml PMMA. The left pedicles were instrumented with monoaxial cannulated pedicle screws. Prior to left screw insertion, a balloon cavity was created and filled with 3 ml of self-curing elastomer (silicone). Each screw was subjected to a cranio-caudal cyclic load starting from - 50 to 50 N while the upper load was increased by 5 N every 100 load cycles until loosening or 11,000 cycles (600 N). After cyclic loading, a pullout test of the screws was conducted. RESULTS: The mean cycles to screw loosening were 9824 ± 1982 and 7401 ± 1644 for the elastomer and PMMA group, respectively (P = 0.012). The post-cycling pullout test of the loosened screws showed differences in the failure mode and failure load, with predominantly pedicle/vertebrae fractures in the PMMA group (1188.6 N ± 288.1) and screw pullout through the pedicle (671.3 N ± 332.1) in the elastomer group. CONCLUSION: The modified pedicle screw augmentation technique involving a balloon cavity creation and a self-curing elastomeric silicone resulted in a significantly improved pedicle screw anchorage under cyclic cranio-caudal loading when compared to conventional in situ PMMA augmentation.


Assuntos
Cimentos Ósseos , Elastômeros/administração & dosagem , Vértebras Lombares/fisiologia , Parafusos Pediculares , Polimetil Metacrilato/administração & dosagem , Suporte de Carga/fisiologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Vértebras Lombares/efeitos dos fármacos , Vértebras Lombares/patologia , Masculino , Teste de Materiais/métodos , Sacro/efeitos dos fármacos , Sacro/patologia , Sacro/fisiologia , Crânio/efeitos dos fármacos , Crânio/patologia , Crânio/fisiologia
12.
Aliment Pharmacol Ther ; 25(9): 1125-32, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17439514

RESUMO

AIM: To test efficacy and safety of polydimethylsiloxane elastomer implants, a silicone biomaterial, in patients with severe faecal incontinence related to an impaired internal anal sphincter. METHODS: Subjects were randomized to receive three injections of 2.5 mL of either physiological saline or polydimethylsiloxane elastomer. After local anaesthesia, an 18 gauge, 2.5-in needle was inserted through the perianal skin and laid down into the intersphincteric space. Treatment (saline or polydimethylsiloxane elastomer) was administered by means of a ratchet gun. Three injections of 2.5 mL each were performed in the area of the internal anal sphincter at 3, 7 and 11 o'clock positions. Main end point was the percentage of subjects in each treatment arm experiencing a successful treatment, defined as a Cleveland Clinic Florida-Faecal Incontinence score <8, 3 months after treatment. Secondary end points were quality of life scores, weekly number of faecal incontinence episodes, subject acceptance and adverse events rate. Both patients and end point assessments were blinded to treatment. RESULTS: 44 women (64.3 +/- 9 years) with a baseline Cleveland Clinic Florida-Faecal Incontinence score > or =8 were enrolled prospectively; 22 received polydimethylsiloxane elastomer and 22 saline treatment. Treatment was well tolerated. At 3 months, the percentage of subjects experiencing a successful treatment was not different between polydimethylsiloxane elastomer and saline groups (23% vs. 27%, respectively, P = 0.73). Moreover, Cleveland Clinic Florida-Faecal Incontinence score was not significantly different between polydimethylsiloxane elastomer and saline groups (11.7 +/- 4.7 vs. 11.4 +/- 4.5, respectively, P = 0.79). CONCLUSIONS: Polydimethylsiloxane elastomer implants cannot be recommended for treatment of severe faecal incontinence related to impaired internal anal sphincter.


Assuntos
Dimetilpolisiloxanos/administração & dosagem , Elastômeros/administração & dosagem , Incontinência Fecal/terapia , Qualidade de Vida/psicologia , Idoso , Canal Anal , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
13.
EBioMedicine ; 26: 47-59, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29208469

RESUMO

Central nervous system (CNS) neurons fail to regrow injured axons, often resulting in permanently lost neurologic function. Tacrolimus is an FDA-approved immunosuppressive drug with known neuroprotective and neuroregenerative properties in the CNS. However, tacrolimus is typically administered systemically and blood levels required to effectively treat CNS injuries can lead to lethal, off-target organ toxicity. Thus, delivering tacrolimus locally to CNS tissues may provide therapeutic control over tacrolimus levels in CNS tissues while minimizing off-target toxicity. Herein we show an electrospun poly(ester urethane) urea and tacrolimus elastomeric matrix (PEUU-Tac) can deliver tacrolimus trans-durally to CNS tissues. In an acute CNS ischemia model in rat, the optic nerve (ON) was clamped for 10s and then PEUU-Tac was used as an ON wrap and sutured around the injury site. Tacrolimus was detected in PEUU-Tac wrapped ONs at 24h and 14days, without significant increases in tacrolimus blood levels. Similar to systemically administered tacrolimus, PEUU-Tac locally decreased glial fibrillary acidic protein (GFAP) at the injury site and increased growth associated protein-43 (GAP-43) expression in ischemic ONs from the globe to the chiasm, consistent with decreased astrogliosis and increased retinal ganglion cell (RGC) axon growth signaling pathways. These initial results suggest PEUU-Tac is a biocompatible elastic matrix that delivers bioactive tacrolimus trans-durally to CNS tissues without significantly increasing tacrolimus blood levels and off-target toxicity.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Traumatismos do Nervo Óptico/tratamento farmacológico , Células Ganglionares da Retina/efeitos dos fármacos , Tacrolimo/administração & dosagem , Animais , Sistema Nervoso Central/fisiopatologia , Sistemas de Liberação de Medicamentos , Elastômeros/administração & dosagem , Elastômeros/química , Humanos , Traumatismos do Nervo Óptico/patologia , Poliésteres/administração & dosagem , Poliésteres/química , Ratos , Células Ganglionares da Retina/patologia , Tacrolimo/química
14.
J Laryngol Otol ; 130(9): 805-10, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27515559

RESUMO

OBJECTIVE: To determine the effectiveness of augmentation surgery using polydimethylsiloxane elastomer injection for the management of patulous eustachian tube. METHOD: All patients were treated with eustachian tube injection augmentation performed via a combined transnasal-transoral endoscopic approach. Clinical presentation, volume of injection, complications and initial response were all prospectively recorded. Longer-term follow up was conducted through structured telephone interviews using previously described patient-reported outcome measures. RESULTS: Overall, 8 of 11 patients (73 per cent) derived complete or significant symptom improvement; 1 patient had significant improvements but was dissatisfied, and in 2 patients the symptoms were unchanged. The eight satisfied patients showed improvement in their quality-of-life scores. CONCLUSION: This study describes an effective treatment option for patulous eustachian tube. Unlike many prior published reports, previously described patient-reported outcome measures were utilised in order to allow more direct comparison.


Assuntos
Dimetilpolisiloxanos/uso terapêutico , Otopatias/cirurgia , Elastômeros/uso terapêutico , Tuba Auditiva/cirurgia , Adulto , Idoso , Dimetilpolisiloxanos/administração & dosagem , Elastômeros/administração & dosagem , Endoscopia/instrumentação , Endoscopia/métodos , Feminino , Seguimentos , Humanos , Injeções/instrumentação , Injeções/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
15.
J Control Release ; 102(3): 607-17, 2005 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-15681083

RESUMO

The application of protein therapeutics for long-term, localized delivery has been hindered by a lack of a delivery device that releases active protein at a concentration within their therapeutic window. A protein delivery system that uses an osmotic pressure delivery mechanism and a photocrosslinked biodegradable elastomer has been designed in an attempt to overcome this limitation. The elastomer is prepared through the UV initiated crosslinking of end terminal acrylated star-poly(epsilon-caprolactone-co-D,L-lactide). Interferon-gamma (IFN-gamma) was released from the optimum formulation at a constant rate of 23 ng/day over 21 days. A cell-based assay showed that over 83% of released IFN-gamma was bioactive. Furthermore, it was demonstrated that bovine serum albumin co-lyophilized with IFN-gamma was released at the same rate as IFN-gamma. This delivery formulation may be clinically useful for sustained, local protein drug delivery applications.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Elastômeros/administração & dosagem , Interferon gama/administração & dosagem , Raios Ultravioleta , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/efeitos da radiação , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Preparações de Ação Retardada/efeitos da radiação , Elastômeros/química , Elastômeros/efeitos da radiação , Interferon gama/química , Interferon gama/efeitos da radiação , Camundongos
16.
Am J Health Syst Pharm ; 68(13): 1251-5, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21690432

RESUMO

PURPOSE: Measures to improve the safe implementation and utilization of an elastomeric infusion system for pain management are described. SUMMARY: Due to the multiple safety concerns associated with the use of the On-Q infusion systems (I-Flow Corporation, Lake Forest, CA) in a community-based teaching institution, a multidisciplinary team of physicians, pharmacists, clinical nurses, nurse educators, and computer informatics personnel was formed to develop a standardized policy and procedure to ensure the safe use of On-Q pumps. The policy addressed several problems concerning prescribing, dispensing, administration, and monitoring of these pumps. The patient care policy for use of On-Q pumps dictates how the pumps are stocked, ordered, dispensed, administered, and monitored and the drugs approved for use in the pumps. Education bulletins, a summary of the new policy and procedure, and a formal presentation of the policy and procedure to unit-based nurse educators were provided. The focus was on a consistent message of safety by reiterating the problems described with these pumps in the literature and in the health care system itself. The physicians ordering the devices have provided positive feedback regarding the simplified ordering process and standardization of the pumps, medications, and concentrations. Both dispensing pharmacists and bedside nurses have noted that the orders are clearly communicated via the computerized system. The addition of documentation in the computer system and education regarding potential signs and symptoms of adverse events with the medication used with the pumps was greatly appreciated by the nursing staff. CONCLUSION: A health care system instituted measures to enhance the safety of using an elastomeric infusion system for pain management.


Assuntos
Controle de Medicamentos e Entorpecentes/métodos , Bombas de Infusão/efeitos adversos , Dor/tratamento farmacológico , Serviço de Farmácia Hospitalar/métodos , Bupivacaína/administração & dosagem , Bupivacaína/efeitos adversos , Sistemas de Liberação de Medicamentos/efeitos adversos , Sistemas de Liberação de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/normas , Elastômeros/administração & dosagem , Elastômeros/efeitos adversos , Humanos , Bombas de Infusão/normas , Dor/metabolismo , Farmacêuticos/normas , Serviço de Farmácia Hospitalar/normas , Segurança
18.
Pharm Res ; 25(10): 2400-12, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18509596

RESUMO

PURPOSE: To develop elastase-sensitive polyurethane scaffolds that would be applicable to the engineering of mechanically active soft tissues. METHODS: A polyurethane containing an elastase-sensitive peptide sequence was processed into scaffolds by thermally induced phase separation. Processing conditions were manipulated to alter scaffold properties and anisotropy. The scaffold's mechanical properties, degradation, and cytocompatibility using muscle-derived stem cells were characterized. Scaffold in vivo degradation was evaluated by subcutaneous implantation. RESULTS: When heat transfer was multidirectional, scaffolds had randomly oriented pores. Imposition of a heat transfer gradient resulted in oriented pores. Both scaffolds were flexible and relatively strong with mechanical properties dependent upon fabrication conditions such as solvent type, polymer concentration and quenching temperature. Oriented scaffolds exhibited anisotropic mechanical properties with greater tensile strength in the orientation direction. These scaffolds also supported muscle-derived stem cell growth more effectively than random scaffolds. The scaffolds expressed over 40% weight loss after 56 days in elastase containing buffer. Elastase-sensitive scaffolds were complete degraded after 8 weeks subcutaneous implantation in rats, markedly faster than similar polyurethanes that did not contain the peptide sequence. CONCLUSION: The elastase-sensitive polyurethane scaffolds showed promise for application in soft tissue engineering where controlling scaffold mechanical properties and pore architecture are desirable.


Assuntos
Implantes Absorvíveis , Anisotropia , Elastômeros/metabolismo , Elastase Pancreática/metabolismo , Poliuretanos/metabolismo , Engenharia Tecidual , Alicerces Teciduais , Animais , Proliferação de Células , Células Cultivadas , Elastômeros/administração & dosagem , Elastômeros/síntese química , Feminino , Hidrólise , Injeções Subcutâneas , Camundongos , Células Musculares/metabolismo , Maleabilidade , Poliuretanos/administração & dosagem , Poliuretanos/síntese química , Porosidade , Ratos , Ratos Endogâmicos Lew , Células-Tronco/metabolismo , Temperatura , Resistência à Tração , Fatores de Tempo
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