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1.
Ir Med J ; 116(No.1): 3, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36917018

RESUMO

BowelScreen paused activity in March 2020 to prioritise the response to the COVID-19 pandemic. The aim of this study was to examine the impact of this delay. Cases affected by the pause and subsequently completed were compared to the same period in 2019. Endoscopy and histology data were obtained from the BowelScreen database and patient records. One-hundred and seven colonoscopies were performed during the study period. This compared with 224 colonoscopies during the same period in 2019. Median lead time to colonoscopy in 2020 was 74 days compared to 34 days in 2019. Adenoma detection rate was 59% for both periods. Advanced adenoma and cancer detection rates were similar in both periods. While there was a marked reduction in activity and significant delays for BowelScreen patients during the first wave of the COVID-19 pandemic, this does not appear to have impacted on clinical outcomes for patients who attended for screening colonoscopy.


Assuntos
Adenoma , COVID-19 , Neoplasias Colorretais , Humanos , SARS-CoV-2 , Pandemias/prevenção & controle , Detecção Precoce de Câncer , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Colonoscopia , Programas de Rastreamento , Adenoma/diagnóstico , Adenoma/epidemiologia
2.
J Assoc Res Otolaryngol ; 22(1): 1-17, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33258054

RESUMO

Intratympanic injection is a clinically used approach to locally deliver therapeutic molecules to the inner ear. Drug diffusion, at least in part, is presumed to occur through the round window membrane (RWM), one of the two openings to the inner ear. Previous studies in human temporal bones have identified a three-layered structure of the RWM with a thickness of 70-100 µm. This is considerably thicker than the RWM in rodents, which are mostly used to model RWM permeability and assess drug uptake. The sheep has been suggested as a large animal model for inner ear research given the similarities in structure and frequency range for hearing. Here, we report the structure of the sheep RWM. The RWM is anchored within the round window niche (average vertical diameter of 2.1 ± 0.3 mm and horizontal diameter of 2.3 ± 0.4 mm) and has a curvature that leans towards the scala tympani. The centre of the RWM is the thinnest (55-71 µm), with increasing thickness towards the edges (< 171 µm), where the RWM forms tight attachments to the surrounding bony niche. The layered RWM structure, including an outer epithelial layer, middle connective tissue and inner epithelial layer, was identified with cellular features such as wavy fibre bundles, melanocytes and blood vessels. An attached "meshwork structure" which extends over the cochlear aqueduct was seen, as in humans. The striking anatomical similarities between sheep and human RWM suggest that sheep may be evaluated as a more appropriate system to predict RWM permeability and drug delivery in humans than rodent models.


Assuntos
Cóclea , Orelha Interna , Janela da Cóclea/anatomia & histologia , Osso Temporal , Animais , Audição , Injeção Intratimpânica , Ovinos
3.
Arch Microbiol ; 200(5): 793-802, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29423561

RESUMO

Whilst colistin (polymyxin E) represents the last mainstream treatment option for multidrug-resistant Gram-negative pathogens, details of its mechanism of action remain to be fully resolved. In this study, the effects of sub-inhibitory, inhibitory-bactericidal, and supra-bactericidal levels of colistin on the membrane integrity and morphology of Escherichia coli and Pseudomonas aeruginosa were investigated using potassium loss, flow cytometry, and scanning electron microscopy (SEM). Supra-bactericidal colistin concentrations induced just 4-12% intracellular potassium loss from bacteria after 24 h. Flow cytometry data suggested colistin might alter cell arrangement, and SEM confirmed the antibiotic causes bacterial aggregation. Filamentation was not detected in either species at any concentration or time-point up to 24 h. These results argue against the hypotheses that colistin kills bacteria by puncturing the cytoplasmic membrane or disrupting DNA synthesis. The colistin-induced bacterial aggregation detected has implications for the interpretation of MBC, time-kill, and other test results obtained with this antibiotic.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Escherichia coli/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Farmacorresistência Bacteriana Múltipla , Escherichia coli/ultraestrutura , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/ultraestrutura
4.
Int J Womens Dermatol ; 4(4): 227-229, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30627622

RESUMO

The association between psychiatric and dermatologic disorders has been well characterized in the present literature with estimates of up to 40% of dermatology patients having concomitant psychiatric problems that are often related to their skin condition. Here, we present our experience regarding the implementation of a psychodermatology clinic in Detroit, Michigan. The most commonly referred conditions were delusions of parasitosis, neurotic excoriations, and isotretinoin initiation for patients with a history of psychiatric conditions. Seventy-three percent of referred patients were female. By creating a monthly clinic for patients who are diagnosed with skin conditions and associated psychiatric disorders or psychological symptoms, we are able to meet the needs of these patients with a synergistic relationship between health care providers.

5.
Int J Pharm ; 515(1-2): 575-582, 2016 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-27771488

RESUMO

Nephropathic cystinosis is a rare autosomal recessive disease characterised by raised lysosomal levels of cystine in the cells of all organs. It is treated by regular administration of the aminothiol, cysteamine. Corneal crystal deposition is one of the most troublesome complications affecting patients and requires the hourly administration of cysteamine eye drops. In an attempt to reduce this frequency and improve the treatment, the preformulation and evaluation of cysteamine containing gels is reported. Suitability for ophthalmic delivery was determined by analysis of rheology, bioadhesion, dissolution and stability. The results demonstrated that three polymers were suitable for ophthalmic delivery of cysteamine; namely sodium hyaluronate, hydroxyethyl cellulose and carbomer 934. Sodium hyaluronate displayed optimum performance in the preformulation tests, being pseudoplastic (reduction in apparent viscosity under increasing shear rate), bioadhesive, releasing cysteamine over 40min and displaying stability over time. In conclusion these results offer the possibility to formulate cysteamine in an ocular applicable gel formulation.


Assuntos
Córnea/efeitos dos fármacos , Cisteamina/química , Cisteamina/farmacologia , Oftalmopatias/tratamento farmacológico , Géis/química , Géis/farmacologia , Resinas Acrílicas/química , Animais , Bovinos , Celulose/análogos & derivados , Celulose/química , Química Farmacêutica/métodos , Cistinose/complicações , Sistemas de Liberação de Medicamentos/métodos , Oftalmopatias/etiologia , Humanos , Ácido Hialurônico/química , Soluções Oftálmicas/química , Soluções Oftálmicas/farmacologia , Polímeros/química , Reologia , Solubilidade
6.
Am J Transplant ; 16(2): 694-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26461049

RESUMO

Pelvic lymphoceles/lymph fistulas are commonly observed after kidney allotransplantation, especially when the kidney is placed in a retroperitoneal position. While the majority are <5 cm in diameter and resolve without intervention, some may continue to enlarge, and cause local or systemic symptoms or graft dysfunction. Among 1662 recipients of both living and deceased donor kidney transplants between January 2003 and July 2014, we found 46 (2.7%) patients with symptomatic lymphoceles requiring intervention. We studied the clinical outcomes and charges for three treatment modalities including open surgical drainage (22), laparoscopic surgical drainage (11), and percutaneous fibrin glue injections into the drained lymphocele cavity (13). The patient demographics and clinical characteristics were comparable for each treatment group, although maintenance immunosuppressive drugs differed by era. We found fibrin glue injections resulted in significantly lower (p = 0.04) rates of recurrence (1; 7.7%) than either laparoscopic (6; 54%) or open surgical drainage (6; 27.3%). In addition, fibrin glue injections generated significantly (p < 0.001) lower median ($4559) charges compared to either laparoscopic ($26,330) or open surgical drainage ($23,758). Fibrin glue treatment has the advantage of being an outpatient procedure, performed with the patient under local anesthesia, and does not incur the expense of an operative procedure or hospital admission associated with laparoscopic or open surgery.


Assuntos
Adesivo Tecidual de Fibrina/administração & dosagem , Fístula/economia , Fístula/terapia , Transplante de Rim/efeitos adversos , Linfocele/economia , Linfocele/terapia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Adulto , Cateterismo , Feminino , Fístula/etiologia , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/economia , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/terapia , Sobrevivência de Enxerto , Custos de Cuidados de Saúde , Humanos , Injeções Intravenosas , Falência Renal Crônica/cirurgia , Testes de Função Renal , Laparoscopia/métodos , Linfocele/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Adesivos Teciduais/administração & dosagem
7.
Int J Pharm ; 490(1-2): 1-8, 2015 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-25980731

RESUMO

A modified hen's egg chorioallantoic membrane (HET-CAM) test has been developed, combining ImageJ analysis with Adobe(®) Photoshop(®). The irritation potential of an ophthalmic medicine can be quantified using this method, by monitoring damage to blood vessels. The evaluation of cysteamine containing hyaluronate gel is reported. The results demonstrated that the novel gel formulation is non-irritant to the ocular tissues, in line with saline solution (negative control). In conclusion, the modification of the established HET-CAM test can quantify the damage to minute blood vessels. These results offer the possibility to formulate cysteamine in an ocular applicable gel formulation.


Assuntos
Alginatos/efeitos adversos , Cisteamina/efeitos adversos , Olho/efeitos dos fármacos , Ácido Hialurônico/efeitos adversos , Irritantes/efeitos adversos , Alternativas aos Testes com Animais/métodos , Animais , Vasos Sanguíneos/efeitos dos fármacos , Química Farmacêutica/métodos , Galinhas , Membrana Corioalantoide , Feminino
8.
Curr Microbiol ; 68(1): 6-11, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23928905

RESUMO

The membrane-active antimicrobial agent chlorhexidine is used extensively as an antiseptic during infection prophylaxis and treatment. Whilst known to induce membrane damage that results in loss of internal solutes from bacteria, the present study sought to determine the rate and extent of cytoplasmic potassium loss and whether any species-specific differences exist. Direct measurement of potassium was achieved using flame emission spectrophotometry. Exposure of selected species to minimum inhibitory (MIC) or minimum bactericidal concentration (MBC) resulted in solute loss that was both concentration and time dependent. Within 5-min treatment with MIC levels, losses of 3 % from P. aeruginosa, 9 % from E. coli, and 15 % from S. aureus were recorded, whilst at 5 % w/v chlorhexidine, elevated loss of 20, 28, and 41 % occurred, respectively. Nonlinear potassium release was evident from all species when treated with 5 % chlorhexidine over a 60-min period. After this contact time, potassium loss from E. coli and S. aureus rose to 93 or 90 %, respectively; in contrast, P. aeruginosa retained 62 % intracellular potassium. Results confirm lethal concentrations of chlorhexidine induce rapid and substantial loss of cytoplasmic potassium from common pathogens. However, bacterial responses vary between species and should be borne in mind when considering mechanism of action.


Assuntos
Anti-Infecciosos Locais/farmacologia , Bactérias/efeitos dos fármacos , Clorexidina/farmacologia , Citoplasma/efeitos dos fármacos , Potássio/análise , Bactérias/química , Bactérias/citologia , Citoplasma/química , Potássio/química , Especificidade da Espécie
9.
Int J Pharm ; 457(1): 40-9, 2013 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-24055598

RESUMO

Reduced oxygen tension combined with high glucose concentration leads to chronic wounds in diabetic patients. Delayed wound healing is due in part to impaired angiogenesis as a result of reduced endothelial cell migration. Topical applications, in the form of sterile lyophilised wafers hold promise for the treatment of chronic diabetic wounds. In this study wafers containing silymarin were prepared using xanthan gum and sterilised with 25 and 40 kGy gamma radiation. The rheological properties of xanthan gels, before and after lyophilisation, were measured and it was concluded that an increased dose of gamma rays (40 kGy) increased the viscosity coefficient and yield stress of silymarin wafers. HPLC analysis indicated that 89-90% of silymarin was retained in the wafers after irradiation. Dermal microvascular cell migration studies in the presence of high glucose and reduced oxygen tension levels, using novel radial migration and wound healing assays developed 'in house', were also undertaken. Silymarin, when formulated as a lyophilised wafer, successfully retained its ability to overcome the high glucose induced reduction in endothelial cell migration.


Assuntos
Antioxidantes/administração & dosagem , Sistemas de Liberação de Medicamentos , Células Endoteliais/efeitos dos fármacos , Silimarina/administração & dosagem , Movimento Celular/efeitos dos fármacos , Células Endoteliais/fisiologia , Glucose , Humanos
10.
Int J Pharm ; 453(2): 462-72, 2013 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-23791735

RESUMO

Lyophilised polysaccharide solutions and gels incorporating the broad spectrum antimicrobial compound, chlorhexidine digluconate (CHD), have potential application as self-adhering, topical delivery systems for the prophylaxis and treatment of wound infections. It is desirable to sterilise these dosage forms but they do not possess suitable thermal properties to be sterilised by autoclaving or dry heat procedures. Ionising radiation may offer a solution hence 'antimicrobial wafers' fabricated from guar (GG), xanthan (XG), karaya (KAG), sodium alginate (SA) and a 50:50 blend of SA:KAG, were gamma-irradiated (25 and 40 kGy). Wafer sterility was qualitatively determined and validated for bacterial and fungal species. The rheological properties of gels reconstituted from irradiated discs ('wafers') were measured and compared with control samples (non-irradiated) to assess changes to the flow properties. Diffusion of CHD from the resultant gels and viscous solutions, and efficacy against Pseudomonas aeruginosa, was determined using a disc diffusion test and release studies conducted in a diffusion cell apparatus. Although there was no change to cast shape, the rheological properties were drastically depleted for all irradiated samples except XG which showed no effective change in consistency, yield stress or efficacy, from the non-irradiated control. SA and SA-KAG samples displayed 'anomalous' release according to Korsmeyer-Peppas.


Assuntos
Anti-Infecciosos/efeitos da radiação , Clorexidina/análogos & derivados , Sistemas de Liberação de Medicamentos , Raios gama , Pseudomonas aeruginosa/efeitos da radiação , Anti-Infecciosos/química , Clorexidina/química , Clorexidina/efeitos da radiação , Géis , Reologia , Esterilização/métodos
11.
Microvasc Res ; 88: 61-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23562913

RESUMO

Delayed wound healing is characteristic of those affected by both Type 1 and Type 2 diabetes. We have developed a novel assay to investigate endothelial cell migration using primary microvascular endothelial cells of dermal origin. Endothelial cell migration was determined using defined monolayers of cells. Net migration or migration at a wounded edge was recorded after 24 or 48 h following incubation in either 20% or 5% oxygen in combination with either 5 mmol/l or 20 mmol/l glucose. Specific intracellular inhibitors of p42/44 MAPK, Pi3 kinase and protein kinase CßII were used. Hypoxia inducible factor type 1 alpha protein was detected using immunocytochemical staining. Cell migration was increased in the presence of hypoxia and decreased with high glucose concentration (p<0.001). The newly developed wound healing assay revealed that re-endothelialisation occurred at a greater rate (p<0.001) than endothelialisation. Inhibition of p42/44MAPK significantly reduced endothelial cell migration at both the intact and the wounded edge in 20 mmol/l glucose but not 5 mmol/l glucose. Inhibition of Pi3 kinase significantly (p<0.001) reduced migration in all test conditions, while inhibition of PKCß restored glucose mediated impaired migration (p>0.05). HIF-1α protein levels did not significantly reduce in the presence of a PKCß inhibitor at the wounded edge of cells in 20 mmol/l glucose. In conclusion, we have established a novel assay to determine endothelial cell migration that is robust and reproducible. Impaired cell migration mediated by high glucose concentration was restored using an inhibitor of the PKCßII pathway which correlated with an increase in the level of HIF1α protein.


Assuntos
Glucose/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Oxigênio/metabolismo , Proteína Quinase C beta/metabolismo , Cicatrização , Movimento Celular , Células Endoteliais/citologia , Endotélio Vascular/citologia , Humanos , Hipóxia , Microcirculação , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Transdução de Sinais , Fatores de Tempo
12.
J Paediatr Child Health ; 49(2): 131-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23331549

RESUMO

AIMS: The aim of this study is to investigate the health-related quality of life in children with severe lower limb trauma after at least 12 months post-injury and to assess patient and injury characteristics in association with the health-related quality of life scores. METHODS: All children in the state of Victoria, who were 18 years of age or younger, suffering from severe lower limb injury before 2006 were studied. Patient and injury characteristics were abstracted from medical records. The health-related quality of life (HRQOL) scores were obtained using the Paediatric Quality of Life Inventory. RESULTS: Thirty-two out of 64 eligible patients participated in this study. All aspects of health-related quality of life in children with severe lower limb trauma after at least 12 months post-injury were significantly poorer compared with non-affected children, particularly in the physical health domain (difference: -12.51 ± 7.43: P < 0.05). It was observed that bilateral limb involvement and the need for soft tissue management were related to poor physical functioning (P < 0.05). Other characteristics such as traumatic amputation, gender, growth plate injury, joint bony injury and accident mechanism did not affect the overall HRQOL scores (P > 0.05). CONCLUSIONS: The HRQOL in children with severe lower limb trauma was significantly impaired even after 12 months post-injury, notably in patient group with bilateral limb involvement and need for soft tissue management. Traumatic amputation, gender, growth plate injury, joint bony injury and accident mechanism did not have an impact on quality of life.


Assuntos
Nível de Saúde , Traumatismos da Perna/psicologia , Qualidade de Vida , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Traumatismos da Perna/fisiopatologia , Masculino , Índices de Gravidade do Trauma , Vitória
13.
Curr Microbiol ; 66(3): 271-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23183933

RESUMO

A targeted approach for direct topical antimicrobial delivery involving the formulation of impregnated freeze-dried wafers prepared from a natural polymer has been assessed to consider potential for treatment of wounded skin. The synthetic cationic antimicrobial peptides (CAPs) NP101 and NP108 were found to have modest in vitro activity against bacterial species commonly associated with wound infections. Minimum inhibitory concentration/minimum bactericidal concentrations against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were found to be 0.31 mg/ml for NP101 and 0.25-0.5 mg/ml for NP108. Rapid, substantial cytoplasmic potassium loss was induced by NP108 in E. coli, but not the other species. Through scanning electron microscopy, both CAPs were observed to alter cell morphology, prevent normal septation, promote cell aggregation and trigger release or formation of extracellular filaments. Wafers harbouring these agents displayed substantial antibacterial activity when assessed by standard diffusion assay. These data confirm that topical delivery of CAPs, through their incorporation within freeze-dried wafer formulations prepared from natural polymers, represents a potential viable approach for treating skin infection.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Administração Tópica , Antibacterianos/administração & dosagem , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Peptídeos Catiônicos Antimicrobianos/química , Química Farmacêutica , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Escherichia coli/ultraestrutura , Liofilização , Testes de Sensibilidade Microbiana , Potássio/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/ultraestrutura , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo , Staphylococcus aureus/ultraestrutura , Infecção dos Ferimentos/tratamento farmacológico
14.
Int J Pharm ; 439(1-2): 157-64, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23085374

RESUMO

There is a requirement to deliver accurate amounts of broad spectrum antimicrobial compounds locally to exuding wounds. Varying amounts of exudate complicates this process by limiting the residence and therefore efficacy of active substances. Minimum bactericidal concentrations (MBC) of antimicrobials are necessary to suppress infection and lessen the chances of resistant strains of potentially pathogenic bacteria from prevailing. Polysaccharide wafers can adhere to exudating wound beds, absorbing fluids and forming highly viscous gels that remain in situ for prolonged periods of time to release sustained amounts of antimicrobial. In this study, five different formulations were produced containing the antimicrobial, chlorhexidine digluconate (CHD). Absorption of simulated wound fluid, resultant rheological properties of gels and efficacy against plated cultures of Pseudomonas aeruginosa were measured and compared. CHD reduced the 'water uptake' of wafers by 11-50% (w/w) and decreased the rheological consistency of non-SA containing gels by 10-65%. Release studies indicated that karaya wafers gave the highest sustained release of CHD, >60 µg/mL in 24 h, well in excess of the MBC for P. aeruginosa. Release kinetics indicated an anomalous diffusion mechanism according to Korsmeyer-Peppas, with diffusion exponents varying from 0.31 to 0.41 for most wafers except xanthan (0.65).


Assuntos
Anti-Infecciosos/administração & dosagem , Clorexidina/análogos & derivados , Sistemas de Liberação de Medicamentos , Pseudomonas aeruginosa/efeitos dos fármacos , Administração Tópica , Alginatos/química , Anti-Infecciosos/química , Clorexidina/administração & dosagem , Clorexidina/química , Liofilização , Galactanos/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Goma de Karaya/química , Cinética , Mananas/química , Testes de Sensibilidade Microbiana , Gomas Vegetais/química , Polissacarídeos Bacterianos/química
15.
J Pharm Sci ; 101(10): 3729-38, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22778070

RESUMO

Nephropathic cystinosis is a rare autosomal recessive disease characterised by raised lysosomal levels of cystine in the cells of all the organs. It is treated by the 6-h oral administration of the aminothiol, cysteamine, which has an offensive taste and smell. In an attempt to reduce this frequency and improve the treatment, cysteamine-containing polyethylene glycol suppositories were prepared and evaluated for dissolution and stability. The results demonstrated that cysteamine release was complete after 30 min, and that there was a uniform drug distribution within the formulations. Twelve-month stability tests highlighted a potential incompatibility among some excipients, although stability was demonstrated for the cysteamine suppositories up to 6 months. These suppositories may provide a useful alternative to the current oral therapy for cystinosis.


Assuntos
Cisteamina/química , Cistinose/tratamento farmacológico , Síndrome de Fanconi/tratamento farmacológico , Síndrome Nefrótica/tratamento farmacológico , Supositórios/química , Química Farmacêutica/métodos , Cisteamina/administração & dosagem , Cistina/metabolismo , Cistinose/metabolismo , Estabilidade de Medicamentos , Excipientes/administração & dosagem , Excipientes/química , Síndrome de Fanconi/metabolismo , Síndrome Nefrótica/metabolismo , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Solubilidade , Supositórios/administração & dosagem
16.
Ther Deliv ; 3(4): 443-55, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22834076

RESUMO

BACKGROUND: Lyophilized wafers have been developed as vehicles for the storage and delivery of therapeutic compounds to exuding wounds. The primary objective of this study was to incorporate a selection of antimicrobial compounds in karaya wafers and measure their efficacy against methicillin-resistant Staphylococcus aureus. METHODS: Four antimicrobial compounds, including an antibiotic, were incorporated within karaya gels and freeze-dried to a shaped-disc form suitable for in vitro testing against methicillin-resistant S. aureus. Disc diffusion and Franz diffusion methods were used to quantify the utility and efficacy of these 'antimicrobial wafers'. Flow rheology and scanning electron microscopy were also used to aid gel and wafer characterization. RESULTS: Lyophilized wafers swelled in simulated wound fluid and released the contained compounds with mixed effect. Povidine-iodine and chlorhexidine were most effective in protein-free buffer while the action of neomycin sulfate was enhanced by the presence of bovine serum albumin. Silver sulfadiazine was the least effective overall.


Assuntos
Antibacterianos/farmacologia , Portadores de Fármacos , Goma de Karaya/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Administração Tópica , Antibacterianos/administração & dosagem , Antibacterianos/química , Química Farmacêutica , Clorexidina/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Composição de Medicamentos , Liofilização , Géis , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Microscopia Eletrônica de Varredura , Neomicina/farmacologia , Povidona-Iodo/farmacologia , Reologia , Sulfadiazina de Prata/farmacologia , Solubilidade , Propriedades de Superfície , Tecnologia Farmacêutica/métodos , Fatores de Tempo
17.
J Rehabil Med ; 44(2): 137-43, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22266600

RESUMO

OBJECTIVE: To examine changes in mobility longitudinally following single-event multilevel surgery in ambulant children with cerebral palsy, focusing on those using assistive devices for functional mobility because they are most at risk of declining gross motor function. PARTICIPANTS: A consecutive sample of 156 ambulant children with cerebral palsy (99 males), 96 without devices (Gross Motor Function Classification System (GMFCS) I/II), 60 with devices (GMFCS III) who had single-event multilevel surgery at mean age 11 years 1 month. METHODS: GMFCS and Functional Mobility Scale (FMS) ratings were recorded pre-operatively and at 2 and 5 years post-operatively. A proportional odds logistic regression model was used for the GMFCS III group to predict the probability of assistive device requirements post-operatively conditional on baseline FMS. RESULTS: Children in GMFCS III showed more change than those in I/II at home and school. Those in GMFCS III using crutches pre-operatively at home and school were more likely to continue using them at 5 years, whereas those using walkers were more likely to change to crutches or wheelchairs. Wheelchairs were most commonly used in the community before and after single-event multilevel surgery. CONCLUSION: Mobility was generally stable or improved at 5 years after single-event multilevel surgery; however, a small number of children used more assistance to facilitate mobility.


Assuntos
Paralisia Cerebral/fisiopatologia , Destreza Motora/fisiologia , Caminhada/fisiologia , Adolescente , Paralisia Cerebral/reabilitação , Paralisia Cerebral/cirurgia , Criança , Humanos , Masculino , Tecnologia Assistiva , Índice de Gravidade de Doença , Volume de Ventilação Pulmonar , Resultado do Tratamento
18.
Drug Dev Ind Pharm ; 38(1): 47-54, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21714725

RESUMO

Drug release characteristics of freeze-dried wafers and solvent-cast films prepared from sodium carboxymethylcellulose have been investigated and compared. In vitro drug dissolution studies were performed using an exchange cell and drug release was measured by UV spectroscopy at 272 nm using distilled water. The dissolution profiles of hydrochlorothiazide from the wafers and films were compared by determining the rates of drug release, estimated from the % release versus time profiles and calculating their difference (f(1)) and similarity (f(2)) factors. The effects of drug loading, polymer content and amount of glycerol (GLY) (films) on the drug release characteristics of both formulations were investigated. Both the wafers and films showed sustained type release profiles that were best explained by the Korsmeyer-Peppas equation. Changes in the concentration of drug and GLY (films) did not significantly alter the release profiles whilst increasing polymer content significantly decreased the rate of drug release from both formulations. The rate of release was faster from the wafers than the corresponding films which could be attributed to differences in the physical microstructure. The results show the potential of employing both formulations in various mucosal drug delivery applications.


Assuntos
Carboximetilcelulose Sódica/química , Sistemas de Liberação de Medicamentos/métodos , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Polímeros/química , Química Farmacêutica , Preparações de Ação Retardada , Liofilização/métodos , Glicerol/química , Concentração de Íons de Hidrogênio , Farmacocinética , Solubilidade , Solventes/química , Água/química
19.
Int J Pharm ; 392(1-2): 192-7, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20382212

RESUMO

Nephropathic cystinosis is a rare autosomal recessive disease characterised by raised lysosomal levels of cystine in the cells of all organs. It is treated by regular administration of the aminothiol, cysteamine. Corneal crystal deposition is one of the most troublesome complications affecting patients and requires the hourly administration of cysteamine eye drops. In an attempt to reduce this frequency and improve the treatment, the preparation and evaluation of cysteamine containing Carbomer gel is reported. The results demonstrated that a weak gel network was formed at low shear-stress, the bioadhesion of the gel was increased with inclusion of a cysteamine derivative (e.g. mean force of 0.067N compared to 0.107N with compound included) and first-order release from the gel was observed. In conclusion these results offer the possibility to formulate cysteamine in an ocular applicable gel formulation.


Assuntos
Resinas Acrílicas/química , Córnea/efeitos dos fármacos , Doenças da Córnea/tratamento farmacológico , Cisteamina/administração & dosagem , Cistinose/complicações , Portadores de Fármacos/química , Adesividade , Animais , Bovinos , Doenças da Córnea/etiologia , Doenças da Córnea/metabolismo , Cisteamina/química , Cisteamina/uso terapêutico , Cistinose/metabolismo , Composição de Medicamentos , Géis , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Estrutura Molecular , Fenilalanina/química , Reologia , Solubilidade
20.
Int J Pharm ; 389(1-2): 24-31, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20083177

RESUMO

Freeze-dried (lyophilised) wafers and solvent cast films from sodium alginate (ALG) and sodium carboxymethylcellulose (CMC) have been developed as potential drug delivery systems for mucosal surfaces including wounds. The wafers (ALG, CMC) and films (CMC) were prepared by freeze-drying and drying in air (solvent evaporation) respectively, aqueous gels of the polymers containing paracetamol as a model drug. Microscopic architecture was examined using scanning electron microscopy, hydration characteristics with confocal laser scanning microscopy and dynamic vapour sorption. Texture analysis was employed to investigate mechanical characteristics of the wafers during compression. Differential scanning calorimetry was used to investigate polymorphic changes of paracetamol occurring during formulation of the wafers and films. The porous freeze-dried wafers exhibited higher drug loading and water absorption capacity than the corresponding solvent evaporated films. Moisture absorption, ease of hydration and mechanical behaviour were affected by the polymer and drug concentration. Two polymorphs of paracetamol were observed in the wafers and films, due to partial conversion of the original monoclinic to the orthorhombic polymorph during the formulation process. The results showed the potential of employing the freeze-dried wafers and solvent evaporated films in diverse mucosal applications due to their ease of hydration and based on different physical mechanical properties exhibited by both type of formulations.


Assuntos
Acetaminofen/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Mucosa/metabolismo , Acetaminofen/química , Alginatos/química , Carboximetilcelulose Sódica/química , Química Farmacêutica/métodos , Cristalização , Liofilização , Géis , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Microscopia Confocal , Microscopia Eletrônica de Varredura , Solventes/química , Água/química , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/metabolismo
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