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Colorectal cancer is a global killer that causes approximately 940 thousand deaths annually. Terminalia ivorensis (TI) is a tropical tree, the bark of which is used in African traditional medicine for the treatment of diabetes, malaria and ulcer. This study investigated TI as a potential anticancer agent in human colon cells in vitro. TI was extracted sequentially with petroleum ether, chloroform, ethyl acetate and ethanol. Antioxidant activity was assessed by DPPH and FRAP, and differential effects on cell viability, growth, DNA damage, DNA repair, and migration were measured in human colon cancer cells (CaCo-2) and/or non-cancerous human colonocytes (NCM460). The TI phytochemicals most strongly associated with these effects were identified by partial least-squares discriminant analysis. DPPH and FRAP activity were highest in TI ethyl acetate and ethanol extracts (p=0.001). All TI extracts significantly inhibited cell viability and growth and induced DNA damage and inhibited DNA repair in both cell models. The majority of TI extracts were significantly (p=0.01) more toxic to cancer cells than non-cancerous colonocytes. DNA repair was significantly (p=0.001) inhibited in CaCo-2 cells by ethyl acetate extract compared with NCM460 cells. Migration was also significantly inhibited (p<0.001) in CaCo-2 by ethyl acetate (80%) and ethanol extracts (75%). Specific benzoic acids, flavonoids and phenols were identified to be strongly associated with these effects. TI displayed strong antioxidant activity and specific anticancer effects by inducing cell death and DNA damage, and by inhibiting DNA repair, cell proliferation and migration.
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BACKGROUND: Terminalia ivorensis (TI) is used in West African ethnomedicine for the treatment of conditions including ulcers, malaria and wounds. Despite its widespread use, the phytochemical profile of TI remains largely undetermined. This research investigated the effects of extraction method, season, and storage conditions on the phytochemical composition of TI to contribute towards understanding the potential benefits. METHODS: TI bark was collected in September 2014, September 2018 and February 2018 during the rainy or dry seasons in Eastern Region, Ghana. Samples were extracted sequentially with organic solvents (petroleum ether, chloroform, ethyl acetate and ethanol) or using water (traditional). Metabolites were identified by liquid chromatography-mass spectrometry/mass spectrometry and compared statistically by ANOVA. RESULTS: A total of 82 different phytochemicals were identified across all samples. A greater yield of the major phytochemicals (44%, p < 0.05) was obtained by water as compared with organic extraction. There was also a higher concentration of metabolites present in cold (63%, p < 0.05) compared with hot water extraction. A significantly (p < 0.05) higher number of phytochemicals were identified from TI collected in the dry (85%) compared to the rainy season (69%). TI bark stored for four years retained 84% of the major phytochemicals. CONCLUSION: This work provides important information on composition and how this is modified by growing conditions, storage and method of extraction informing progress on the development of TI as a prophylactic formulation or medicine.
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Extratos Vegetais , Terminalia , Extratos Vegetais/química , Terminalia/química , Estações do Ano , Compostos Fitoquímicos/análise , Solventes/química , ÁguaRESUMO
Billions of people live in urban poverty, with many forced to reside in disaster-prone areas. Research suggests that such disasters harm child nutrition and increase adult morbidity. However, little is known about impacts on mental health, particularly of people living in slums. In this paper we estimate the effects of flood disasters on the mental and physical health of poor adults and children in urban Indonesia. Our data come from the Indonesia Family Life Survey and new surveys of informal settlement residents. We find that urban poor populations experience increases in acute morbidities and depressive symptoms following floods, that the negative mental health effects last longer, and that the urban wealthy show no health effects from flood exposure. Further analysis suggests that worse economic outcomes may be partly responsible. Overall, the results provide a more nuanced understanding of the morbidities experienced by populations most vulnerable to increased disaster occurrence.
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Depressão , Inundações , Pobreza , População Urbana , Populações Vulneráveis , Adulto , Criança , Depressão/epidemiologia , Depressão/etiologia , Desastres , Humanos , Saúde Mental , MorbidadeRESUMO
AIM: To determine the association of peroxisome proliferator activated receptor gamma coactivator 1 Gly482Ser variant with components of metabolic syndrome. MATERIALS AND METHODS: A systematic search was carried out using Web of Science, PubMed, EMBASE and the Cochrane library using the key words: Peroxisome proliferator activator receptor gamma coactivator 1, PPARGC1A, PGC-1, PGC-1alpha, and PGC1alpha alone or with polymorphism, Gly482Ser and rs8192678. RESULTS: Data from 19 articles generated 28 separate data sets. Under the recessive model fasting plasma glucose was significantly lower in AA genotypes when compared to GGâ¯+â¯GA in the total sample group and in non-Asian group (pâ¯<â¯.001). The AA genotype showed significantly lower levels of total cholesterol compared to GGâ¯+â¯GA genotype using the recessive model with the non-Asian group (pâ¯<â¯.05). Under the dominant model, body mass index of the GG genotype was significantly higher in Asian subgroups (pâ¯<â¯.05). CONCLUSION: PPARGC1A Gly482Ser variant impacts differently in Asian population groups.
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Síndrome Metabólica/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Polimorfismo de Nucleotídeo Único , Adulto , Povo Asiático/genética , Colesterol/sangue , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-IdadeRESUMO
This paper discusses two types of response-scale heterogeneity, which may impact upon the EQ-5D. Response-scale heterogeneity in reporting occurs when individuals systematically differ in their use of response scales when responding to self-assessments. This type of heterogeneity is widely observed in relation to other self-assessed measures but is often overlooked with regard to the EQ-5D. Analogous to this, preference elicitation involving the EQ-5D could be subject to a similar type of heterogeneity, where variations across respondents may occur in the interpretations of the levels (response categories) being valued. This response-scale heterogeneity in preference elicitation may differ from variations in preferences for health states, which have been observed in the literature. This paper explores what these forms of response-scale heterogeneity may mean for the EQ-5D and the potential implications for researchers who rely on the instrument as a measure of health and quality of life. We identify situations where they are likely to be problematic and present potential avenues for overcoming these issues. Copyright © 2016 John Wiley & Sons, Ltd.
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Nível de Saúde , Autoavaliação (Psicologia) , Inquéritos e Questionários , Humanos , Modelos Estatísticos , Anos de Vida Ajustados por Qualidade de VidaRESUMO
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.
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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 TempoRESUMO
Extreme heat negatively impacts cognition, learning, and task performance. With increasing global temperatures, workers may therefore be at increased risk of work-related injuries and illness. This study estimates the effects of temperature on worker health using records spanning 1985-2020 from an Australian mandatory insurance scheme. High temperatures are found to cause significantly more claims, particularly among manual workers in outdoor-based industries. These adverse effects have not diminished across time, with the largest effect observed for the 2015-2020 period, indicating increasing vulnerability to heat. Within occupations, the workers most adversely affected by heat are female, older-aged and higher-earning. Finally, results from firm-level panel analyses show that the percentage increase in claims on hot days is largest at "safer" firms.
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Exposição Ocupacional , Traumatismos Ocupacionais , Humanos , Feminino , Masculino , Temperatura Alta , Austrália/epidemiologia , Exposição Ocupacional/efeitos adversos , TemperaturaRESUMO
OBJECTIVE: To use patient-level data, clinical information and linked Medicare records to assess the distribution of benefits (rebates) across income groups, including benefits relating to chronic conditions such as the Chronic Disease Dental Scheme (CDDS). DESIGN, SETTING AND PARTICIPANTS: Nationally representative, cluster-stratified survey (the Australian Hypertension and Absolute Risk Study) involving 322 general practitioners who each collected clinical data on 15-20 patients aged≥55,2012s who presented between 1 April 2008 and 30 June 2008 and who consented to have their information linked with Medicare administrative records over 12 months. MAIN OUTCOME MEASURES: Distribution of total out-of-hospital Medicare expenditure quantified using concentration indices and determinants of use calculated by odds ratios. RESULTS: There were 2862 patients in the study. After controlling for need, the concentration index for overall funding was slightly progressive (pro-poor) at -0.008 (95% CI, -0.009 to -0.008). Medicare expenditure on chronic care-related services consistently contributed to progressivity of the overall scheme, particularly services under the CDDS with a need-adjusted concentration index of -0.205 (95% CI, -0.208 to -0.201). Uptake of chronic care items varied by locality and comorbid conditions (there was greater uptake by patients with one or more comorbid conditions). CONCLUSIONS: Chronic care items, particularly dental items, have primarily been used by individuals from lower income households. Uptake of chronic care items contributes to the overall progressivity of Medicare.
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Gastos em Saúde/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde/economia , Renda/estatística & dados numéricos , Assistência de Longa Duração/economia , Medicare/economia , Idoso , Idoso de 80 Anos ou mais , Austrália , Doença Crônica , Feminino , Clínicos Gerais , Humanos , Masculino , Medicare/estatística & dados numéricos , Pessoa de Meia-Idade , Estados UnidosRESUMO
PURPOSE: The influence of polymer architecture on cellular uptake and transport across Caco-2 cells of novel amphiphilic polyelectrolyte-insulin nanocomplexes was investigated. METHOD: Polyallylamine (PAA) (15 kDa) was grafted with palmitoyl chains (Pa) and subsequently modified with quaternary ammonium moieties (QPa). These two amphiphilic polyelectrolytes (APs) were tagged with rhodamine, and their uptake by Caco-2 cells or their polyelectrolyte complexes (PECs) with fluorescein isothiocyanate-insulin (FITC-insulin) uptake was investigated using fluorescence microscopy. The integrity of the monolayer was determined by measurement of transepithelial electrical resistance (TEER), and insulin transport across the monolayers was determined. RESULT: Pa and insulin were co-localised in cell membranes, while QPa complexes were found within the cytoplasm. QPa complex uptake was not affected by calcium, cytochalasin D or nocodazole. Uptake was reduced by co-incubation with sodium azide, an active transport inhibitor. Both polymers opened tight junctions reversibly, and insulin transport through monolayers increased when QPa or Pa was used. CONCLUSION: These APs have been shown to be taken up by Caco-2 cells and reversibly open tight cell junctions. Further work is required to optimise these formulations with a view to maximising their potential to facilitate oral delivery of insulin.
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Eletrólitos/química , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Nanoconjugados/química , Tensoativos/química , Administração Oral , Transporte Biológico , Células CACO-2 , Técnicas de Cultura de Células , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Insulina/química , Insulina/farmacocinética , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Ácidos Palmíticos/química , Poliaminas/química , Succinimidas/química , Trometamina/químicaRESUMO
Nephropathic cystinosis is a rare autosomal recessive disease characterised by raised intracellular levels of the amino acid, cystine. If untreated, the disease, progressively deteriorates towards end stage renal disease (ESRD) at the end of the first decade. The disease is caused by a defect in the lysosomal transport mechanism for cystine. The treatment of choice is the aminothiol cysteamine which acts as a lysine mimic. However, cysteamine possesses an offensive taste and smell and irritates the gastrointestinal tract leading to nausea and vomiting following administration. Furthermore, the rapid metabolism of cysteamine requires oral administration every 6 h for life, in consequence, the patient compliance is poor. As part of our continuing work to obtain new pro-drugs for the treatment of this genetic disease, we have synthesised a folate derivative of cystamine, the disulfide derivative of cysteamine. This new pro-drug was non cytotoxic, showed greater ability to deplete intralysosomal cystine than the current treatment, and, in fact has been the most effective reducer of intralysosomal cystine discovered in our laboratories to date.
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Cistamina/química , Pró-Fármacos/química , Administração Oral , Linhagem Celular , Cistamina/farmacocinética , Cistamina/uso terapêutico , Cistinose , Síndrome de Fanconi , Humanos , Síndrome Nefrótica/tratamento farmacológico , Pró-Fármacos/farmacocinética , Pró-Fármacos/uso terapêuticoRESUMO
The genetic disease, nephropathic cystinosis is characterized by lysosomal accumulation of the amino acid cystine. Crystallization of cystine in affected organs, if untreated, results in mortality of the affected individuals by their middle to late teens. The only approved treatment for cystinosis is administration of cysteamine. However, cysteamine is associated with an offending odor and taste and this, coupled to a rapid first pass metabolism and a 6h dosing regimen, suggest a clear need to improve the therapy. A number of PEGylated derivatives of cystamine, the disulfide counterpart of cysteamine, have been synthesised and evaluated in cultured cystinotic fibroblasts for toxicity and efficacy. All of the tested compounds were non-cytotoxic and displayed a remarkable depletion of intralysosomal cystine.
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Cistamina/análogos & derivados , Polietilenoglicóis/química , Células Cultivadas , Cistamina/uso terapêutico , Cistamina/toxicidade , Cistinose , Síndrome de Fanconi , Fibroblastos/efeitos dos fármacos , Humanos , Síndrome Nefrótica/tratamento farmacológico , Pró-Fármacos/química , Pró-Fármacos/uso terapêutico , Pró-Fármacos/toxicidadeRESUMO
As part of our continuing work to obtain new pro-drugs for the treatment of nephropathic cystinosis, a number of glutaric and succinic acid derivatives of cystamine have been designed, synthesised and biologically evaluated in vitro. These compounds have been designed as odourless and tasteless pro-drugs which will release multiple molecules of cysteamine upon administration. All of the synthesised compounds evaluated in this study were non-cytotoxic and displayed a greater ability than cysteamine to deplete the levels of cystine in cultured fibroblasts.
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Cistamina/análogos & derivados , Síndrome Nefrótica/tratamento farmacológico , Pró-Fármacos/síntese química , Cistamina/uso terapêutico , Cistamina/toxicidade , Cistinose , Síndrome de Fanconi , Fibroblastos/efeitos dos fármacos , Glutaratos/química , Humanos , Pró-Fármacos/uso terapêutico , Pró-Fármacos/toxicidade , Ácido Succínico/químicaRESUMO
The EPO-TBI multi-national randomized controlled trial found that erythropoietin (EPO), when compared to placebo, did not affect 6-month neurological outcome, but reduced illness severity-adjusted mortality in patients with traumatic brain injury (TBI), making the cost-effectiveness of EPO in TBI uncertain. The current study uses patient-level data from the EPO-TBI trial to evaluate the cost-effectiveness of EPO in patients with moderate or severe TBI from the healthcare payers' perspective. We addressed the issue of transferability in multi-national trials by estimating costs and effects for specific geographical regions of the study (Australia/New Zealand, Europe, and Saudi Arabia). Unadjusted mean quality-adjusted life-years (QALYs; 95% confidence interval [CI]) at 6 months were 0.027 (0.020-0.034; p < 0.001) higher in the EPO group, with an adjusted QALY increment of 0.014 (0.000-0.028; p = 0.04). Mean unadjusted costs (95% CI) were $US5668 (-9191 to -2144; p = 0.002) lower in the treatment group; controlling for baseline IMPACT-TBI score and regional heterogeneity reduced this difference to $2377 (-12,446 to 7693; p = 0.64). For a willingness-to-pay threshold of $US50,000 per QALY, 71.8% of replications were considered cost-effective. Therefore, we did not find evidence that EPO was significantly cost-effective in the treatment of moderate or severe TBI at 6-month follow-up.
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Lesões Encefálicas Traumáticas/tratamento farmacológico , Eritropoetina/economia , Eritropoetina/uso terapêutico , Fármacos Neuroprotetores/economia , Fármacos Neuroprotetores/uso terapêutico , Adulto , Lesões Encefálicas Traumáticas/mortalidade , Análise Custo-Benefício , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Anos de Vida Ajustados por Qualidade de Vida , Resultado do Tratamento , Adulto JovemRESUMO
Nephropathic cystinosis is a rare autosomal recessive disease characterised by raised lysosomal levels of cystine in the cells of most organs. The disorder is treated by regular administration of the aminothiol, cysteamine, an odiferous and unpleasant tasting compound that along with its metabolites is excreted in breath and sweat, leading to poor patient compliance. In an attempt to improve patient compliance a series of novel prodrugs has been designed and evaluated as a potential new treatment for nephropathic cystinosis. The first of the prodrugs tested, 3a, was found to decrease the levels of intracellular cystine in cystinotic fibroblasts. This is the first report of a potential new therapeutic treatment for nephropathic cystinosis since the advent of cysteamine bitartrate.
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Cisteamina/análogos & derivados , Cisteamina/farmacologia , Cistinose/tratamento farmacológico , Células Cultivadas , Cisteamina/química , Células Epiteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Humanos , Estrutura Molecular , Pró-FármacosRESUMO
Non-alcoholic fatty liver disease (NAFLD) is often linked with impaired hepatic autophagy. Here, we studied the alterations in hepatocellular autophagy by high cholesterol and high-fat diet (HC-HF) diet in C57BL/6J mice, and by palmitic acid (PA), in AML-12 and HepG2 cells. Further, we analysed role of Trigonelline (TG), a plant alkaloid, in preventing NAFLD, by modulating autophagy. For this, C57BL/6J mice were fed with Standard Chow (SC) or HC-HF diet, with and without TG for 16 weeks. In-vitro; AML-12â¯cells and HepG2 cells, were exposed to PA with and without TG, for 24â¯h. Cellular events related to autophagy, lipogenesis, and lipo-toxicity were studied. The HC-HF diet fed mice showed hepatic autophagy blockade, increased triglycerides and steatosis. PA exposure to AML-12â¯cells and HepG2 cells induced impaired autophagy, ER stress, resulting in lipotoxicity. TG treatment in HC-HF fed mice, restored hepatic autophagy, and prevented steatosis. TG treated AML-12, and HepG2 cells exposed to PA showed autophagy restoration, and reduced lipotoxicity, however, these effects were diminished in Atg7-/- HepG2 cells, and in the presence of chloroquine. This study shows that HC-HF diet-induced impaired autophagy, and steatosis is prevented by TG, which attributes to its novel mechanism in treating NAFLD.
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Alcaloides/farmacologia , Autofagia/efeitos dos fármacos , Colesterol/administração & dosagem , Dieta Hiperlipídica/efeitos adversos , Fígado Gorduroso/induzido quimicamente , Ração Animal/análise , Animais , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fígado Gorduroso/prevenção & controle , Inativação Gênica , Humanos , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Regulação para Cima , Aumento de PesoRESUMO
Systematic differences in the ways that people use and interpret response categories (differential item functioning, DIF) can introduce bias when using self-assessments to compare health or quality of life across heterogeneous groups. This paper reports on an exploratory analysis involving the use of anchoring vignettes to identify DIF in a commonly used measure for assessing health-related quality of life - namely the EQ-5D. Using data from a bespoke (i.e. custom) survey that recruited a representative sample of 4300 respondents from the general Australian population in 2014 and 2015, we find that the assumptions of response consistency (RC) and vignette equivalence (VE) hold in a sub-sample of respondents aged 55-65 years (n = 914), which demonstrates that vignettes can appropriately identify DIF in EQ-5D reporting for this age group. We find that the EQ-5D is indeed subject to DIF, and that failure to account for DIF can lead to conclusions that are misleading when using the instrument to compare health or quality of life across heterogeneous groups. We also provide several important insights in terms of the identifying assumptions of RC and VE. We conclude that the implications of DIF could be of considerable importance, not only for outcomes research, but for funding decisions in healthcare more broadly given the strong reliance on patient-reported outcome measures in economic evaluations for health technology assessment.
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Atividades Cotidianas/psicologia , Nível de Saúde , Qualidade de Vida/psicologia , Autorrelato/normas , Pesos e Medidas/instrumentação , Adulto , Idoso , Austrália , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
There is a growing appetite for large complex databases that integrate a range of personal, socio-demographic, health, genetic and financial information on individuals. It has been argued that 'Big Data' will provide the necessary catalyst to advance both biomedical research and health economics and outcomes research. However, it is important that we do not succumb to being data rich but information poor. This paper discusses the benefits and challenges of building Big Data, analysing Big Data and making appropriate inferences in order to advance cancer care, using Cancer 2015 (a prospective, longitudinal, genomic cohort study in Victoria, Australia) as a case study. Cancer 2015 has been linked to State and Commonwealth reimbursement databases that have known limitations. This partly reflects the funding arrangements in Australia, a country with both public and private provision, including public funding of private healthcare, and partly the legislative frameworks that govern data linkage. Additionally, linkage is not without time delays and, as such, achieving a contemporaneous database is challenging. Despite these limitations, there is clear value in using linked data and creating Big Data. This paper describes the linked Cancer 2015 dataset, discusses estimation issues given the nature of the data and presents panel regression results that allow us to make possible inferences regarding which patient, disease, genomic and treatment characteristics explain variation in health expenditure.
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Bases de Dados Factuais/estatística & dados numéricos , Economia Médica , Gastos em Saúde/estatística & dados numéricos , Neoplasias/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália , Estudos de Coortes , Feminino , Genômica , Humanos , Estudos Longitudinais , Masculino , Registro Médico Coordenado , Pessoa de Meia-Idade , Neoplasias/economia , Avaliação de Resultados em Cuidados de Saúde/métodos , Estudos ProspectivosRESUMO
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.
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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 , SolubilidadeRESUMO
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.