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1.
Age Ageing ; 51(6)2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35751872

RESUMO

International human rights movements have improved the visibility and equality of lesbian, gay, bisexual and transgender+ (LGBT+) communities and their members. Health outcomes for LGBT+ people remain, however, worse than for their non-LGBT+ peers. Older LGBT+ people have experienced fewer positive changes, in part due to their lived experience of discrimination and their ongoing, unintentional invisibility in medical and social care. This article highlights the impacts of societal structure, health and social care on the lives of older LGBT+ people including physical and mental health, End of Life, Dementia, Housing and Care Settings, and a focus on the experiences of trans-people. We look at the existing improvements developed by LGBT+ communities (and their allies) and propose refreshing Person-Centred Care to improve inclusivity. Finally, we provide a framework for looking at the areas in which service challenges arise and suggest ways to address these to make health and social care services more ready to meet the needs of older LGBT+ people.


Assuntos
Melhoria de Qualidade , Minorias Sexuais e de Gênero , Bissexualidade/psicologia , Feminino , Humanos , Saúde Mental , Apoio Social
2.
Glob Chang Biol ; 20(9): 2815-28, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24638986

RESUMO

Understanding how climate change can affect crop-pollinator systems helps predict potential geographical mismatches between a crop and its pollinators, and therefore identify areas vulnerable to loss of pollination services. We examined the distribution of orchard species (apples, pears, plums and other top fruits) and their pollinators in Great Britain, for present and future climatic conditions projected for 2050 under the SRES A1B Emissions Scenario. We used a relative index of pollinator availability as a proxy for pollination service. At present, there is a large spatial overlap between orchards and their pollinators, but predictions for 2050 revealed that the most suitable areas for orchards corresponded to low pollinator availability. However, we found that pollinator availability may persist in areas currently used for fruit production, which are predicted to provide suboptimal environmental suitability for orchard species in the future. Our results may be used to identify mitigation options to safeguard orchard production against the risk of pollination failure in Great Britain over the next 50 years; for instance, choosing fruit tree varieties that are adapted to future climatic conditions, or boosting wild pollinators through improving landscape resources. Our approach can be readily applied to other regions and crop systems, and expanded to include different climatic scenarios.


Assuntos
Distribuição Animal , Abelhas/fisiologia , Clima , Modelos Biológicos , Polinização/fisiologia , Animais , Produtos Agrícolas , Demografia , Reino Unido
3.
Eur J Pharm Biopharm ; 199: 114291, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641230

RESUMO

The CLEFF4 sub clone from stock late passage Caco2 cells has a unique property of being able to develop polarised cell monolayers with high P-gp expression and tight junctions much quicker than the original cell line. Instead of being useful for transport studies 21-24 days after initiating culture, the CLEFF4 cell line matures in 5-6 days with tight junctions surpassing that of 3 week old Caco2 cells in that time frame [1]. This has enabled the CLEFF4 cell line to provide measures of apparent permeability for potential drug candidates, so important for pre-clinical drug development, 4 times faster than the original cell line. RNA samples were collected and analysed at days 4 and 7 of culture over a 3 year period and had full RNA transcriptome analysed by the ranaseq.eu open bioinformatics platform. Protein was also collected from day 4 to day 22 of culture. Differential expression data from the FASTQ files have shown significant differences in expression in multiple genes involved with drug efflux, tight junctions, phase 2 metabolism and growth factors, which have been confirmed from protein determination that may hold the key to understanding accelerated human cell maturation. These gene expression results may be significant for other tissues beyond the gastrointestinal tract, and potentially for accelerated cell growth for the new field of laboratory grown tissues for organ replacement. The data also confirms the different genetic expression in CLEFF4 cells compared to Caco2 and the stable nature of the different expression over many years.


Assuntos
Junções Íntimas , Transcriptoma , Humanos , Células CACO-2 , Junções Íntimas/metabolismo , Western Blotting
4.
Front Cell Infect Microbiol ; 14: 1353971, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38449827

RESUMO

The COVID-19 pandemic has had a significant and lasting impact on the world. Four years on, despite the existence of effective vaccines, the continuous emergence of new SARS-CoV-2 variants remains a challenge for long-term immunity. Additionally, there remain few purpose-built antivirals to protect individuals at risk of severe disease in the event of future coronavirus outbreaks. A promising mechanism of action for novel coronavirus antivirals is the inhibition of viral entry. To facilitate entry, the coronavirus spike glycoprotein interacts with angiotensin converting enzyme 2 (ACE2) on respiratory epithelial cells. Blocking this interaction and consequently viral replication may be an effective strategy for treating infection, however further research is needed to better characterize candidate molecules with antiviral activity before progressing to animal studies and clinical trials. In general, antiviral drugs are developed from purely synthetic compounds or synthetic derivatives of natural products such as plant secondary metabolites. While the former is often favored due to the higher specificity afforded by rational drug design, natural products offer several unique advantages that make them worthy of further study including diverse bioactivity and the ability to work synergistically with other drugs. Accordingly, there has recently been a renewed interest in natural product-derived antivirals in the wake of the COVID-19 pandemic. This review provides a summary of recent research into coronavirus entry inhibitors, with a focus on natural compounds derived from plants, honey, and marine sponges.


Assuntos
Produtos Biológicos , COVID-19 , Inibidores da Fusão de HIV , Humanos , Animais , Produtos Biológicos/farmacologia , Pandemias , Surtos de Doenças
5.
Sci Rep ; 13(1): 4499, 2023 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934125

RESUMO

The objective of this study was to develop a fully automated multiple-cow real-time lameness detection system using a deep learning approach for cattle detection and pose estimation that could be deployed across dairy farms. Utilising computer vision and deep learning, the system can analyse simultaneously both the posture and gait of each cow within a camera field of view to a very high degree of accuracy (94-100%). Twenty-five video sequences containing 250 cows in varying degrees of lameness were recorded and independently scored by three accredited Agriculture and Horticulture Development Board (AHDB) mobility scorers using the AHDB dairy mobility scoring system to provide ground truth lameness data. These observers showed significant inter-observer reliability. Video sequences were broken down into their constituent frames and with a further 500 images downloaded from google, annotated with 15 anatomical points for each animal. A modified Mask-RCNN estimated the pose of each cow to output 5 key-points to determine back arching and 2 key-points to determine head position. Using the SORT (simple, online, and real-time tracking) algorithm, cows were tracked as they move through frames of the video sequence (i.e., in moving animals). All the features were combined using the CatBoost gradient boosting algorithm with accuracy being determined using threefold cross-validation including recursive feature elimination. Precision was assessed using Cohen's kappa coefficient and assessments of precision and recall. This methodology was applied to cows with varying degrees of lameness (according to accredited scoring, n = 3) and demonstrated that some characteristics directly associated with lameness could be monitored simultaneously. By combining the algorithm results over time, more robust evaluation of individual cow lameness was obtained. The model showed high performance for predicting and matching the ground truth lameness data with the outputs of the algorithm. Overall, threefold lameness detection accuracy of 100% and a lameness severity classification accuracy of 94% respectively was achieved with a high degree of precision (Cohen's kappa = 0.8782, precision = 0.8650 and recall = 0.9209).


Assuntos
Doenças dos Bovinos , Aprendizado Profundo , Feminino , Bovinos , Animais , Coxeadura Animal/diagnóstico , Reprodutibilidade dos Testes , Doenças dos Bovinos/diagnóstico , Marcha , Indústria de Laticínios/métodos , Lactação
6.
Toxicol Appl Pharmacol ; 260(3): 294-302, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22464980

RESUMO

There is concern that P-glycoprotein mediated efflux contributes to steroid resistance. Therefore, this study examined bidirectional corticosteroid transport and induction capabilities for P-glycoprotein (P-gp) to understand which of the systemic and inhaled corticosteroids interacted with P-gp to the greatest extent. Hydrocortisone, prednisolone, prednisone, methylprednisolone, and dexamethasone represented systemically active drugs, while fluticasone propionate, beclomethasone dipropionate, ciclesonide and budesonide represented inhaled corticosteroids. Aldosterone and fludrocortisone represented mineralocorticoids. All drugs were detected using individually optimised HPLC protocols. Transport studies were conducted through Caco-2 monolayers. Hydrocortisone and aldosterone had efflux ratios below 1.5, while prednisone showed a P-gp mediated efflux ratio of only 1.8 compared to its active drug, prednisolone, with an efflux ratio of 4.5. Dexamethasone and beclomethasone had efflux ratios of 2.1 and 3.3 respectively, while this increased to 5.1 for methylprednisolone. Fluticasone showed an efflux ratio of 2.3. Protein expression studies suggested that all of the inhaled corticosteroids were able to induce P-gp expression, from 1.6 to 2 times control levels. Most of the systemic corticosteroids had higher passive permeability (>20×10(-6) cm/s) compared to the inhaled corticosteroids (>5×10(-6) cm/s), except for budesonide, with permeability similar to the systemic corticosteroids. Inhaled corticosteroids are not transported by P-gp to the same extent as systemic corticosteroids. However, they are able to induce P-gp production. Thus, inhaled corticosteroids may have greater interactions with other P-gp substrates, but P-gp itself is less likely to influence resistance to the drugs.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Glucocorticoides/farmacocinética , Hidroxicorticosteroides/farmacocinética , Administração por Inalação , Administração Oral , Transporte Biológico , Células CACO-2 , Resistência a Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/administração & dosagem , Humanos , Hidroxicorticosteroides/administração & dosagem , Permeabilidade
7.
Xenobiotica ; 42(6): 538-49, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22188412

RESUMO

Caco-2 cells were used to compare P-gp mediated efflux and passive permeability using bidirectional transport of 11 antihistamines. An efflux ratio >2 indicated active efflux, with PSC833 and GF120918 used as functional P-gp inhibitors. Antihistamines were measured directly by HPLC or LC/MS. Fexofenadine had an efflux ratio of 37, yet had negligible passive permeability, even in the presence of a pH gradient (0.1 × 10(-6) cm/sec). Its precursor, terfenadine, had an efflux ratio of 2.5, while cetirizine, desloratadine and hydroxyzine were 4, 7 and 14, respectively. After incubation with P-gp inhibitors, these ratios dropped significantly. Loratadine, by contrast, had equivalent transport in both directions and passive permeability was high (24 × 10(-6) cm/sec). Dimenhydrinate was the only other sedating antihistamine to exhibit efflux, with a ratio of 10. Gradient conditions of pH (6/7.4) increased efflux of terfenadine and desloratadine to over 31 and 38 fold respectively, yet this increased efflux was not associated with P-gp. Altering functional P-gp in the gut is likely to influence absorption of some sedating antihistamines such as dimenhydrinate and hydroxyzine and most less-sedating antihistamines except loratadine. In addition, desloratadine exhibits pH dependent efflux which could further induce variable absorption of this antihistamine.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Antagonistas dos Receptores Histamínicos H1/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Transporte Biológico , Células CACO-2 , Cetirizina/farmacocinética , Cromatografia Líquida de Alta Pressão , Interações Medicamentosas , Antagonistas dos Receptores Histamínicos H1/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Absorção Intestinal , Loratadina/análogos & derivados , Loratadina/farmacocinética , Espectrometria de Massas , Permeabilidade , Terfenadina/análogos & derivados , Terfenadina/farmacocinética
8.
Biology (Basel) ; 11(1)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35053127

RESUMO

The prevalence of type 2 diabetes mellitus is rising globally and this disease is proposed to be the next pandemic after COVID-19. Although the cause of type 2 diabetes mellitus is unknown, it is believed to involve a complex array of genetic defects that affect metabolic pathways which eventually lead to hyperglycaemia. This hyperglycaemia arises from an inability of the insulin-sensitive cells to sufficiently respond to the secreted insulin, which eventually results in the inadequate secretion of insulin from pancreatic ß-cells. Several treatments, utilising a variety of mechanisms, are available for type 2 diabetes mellitus. However, more medications are needed to assist with the optimal management of the different stages of the disease in patients of varying ages with the diverse combinations of other medications co-administered. Throughout modern history, some lead constituents from ancient medicinal plants have been investigated extensively and helped in developing synthetic antidiabetic drugs, such as metformin. Teucrium polium L. (Tp) is a herb that has a folk reputation for its antidiabetic potential. Previous studies indicate that Tp extracts significantly decrease blood glucose levels r and induce insulin secretion from pancreatic ß-cells in vitro. Nonetheless, the constituent/s responsible for this action have not yet been elucidated. The effects appear to be, at least in part, attributable to the presence of selected flavonoids (apigenin, quercetin, and rutin). This review aims to examine the reported glucose-lowering effect of the herb, with a keen focus on insulin secretion, specifically related to type 2 diabetes mellitus. An analysis of the contribution of the key constituent flavonoids of Tp extracts will also be discussed.

9.
Breastfeed Med ; 17(12): 1011-1017, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36315169

RESUMO

Background: Breastfeeding-related adverse drug reactions (ADRs) are thought to be uncommon as reported cases are globally low. The nonspecific nature of these reactions and a lack of awareness and difficulty in identification of ADRs by mothers and clinicians may result in these ADRs being underreported. Aims: This study hypothesized that breastfeeding-related infant ADRs are more frequent than reported. As a first-hand account of breastfeeding mothers, this study aimed to evaluate the impact of the perceived ADRs on the continuation of breastfeeding and maternal treatment. Methods: Women currently breastfeeding or having breastfed in the last 12 months were invited to complete an online survey. The survey comprised 42 questions in 5 sections to obtain data from breastfeeding mothers, including their use of medicines during lactation, perceptions of infant adverse reactions attributable to maternal medication use and its potential impact on breastfeeding. Results: This online survey was completed by 339 women, 42% of whom reported taking at least one medication during breastfeeding. ADRs were reported in 23 infants where a possible or probable causal relationship indicated by a Naranjo score of 1-8 was established in 16 (11.3%). Antibiotics (n = 12) and opioids (n = 2), including tramadol and oxycodone were identified as the most common adverse reaction-causing drugs. The average age of infants at the time of the perceived ADR was 25.6 days (95% confidence interval; 4-85 days; median age 17.5 days). Conclusion: Suspected ADR reporting in this study was significantly greater than those reported to the regulatory body, the Australian Therapeutics Goods Administration, which shows that common breastfeeding-related infant ADRs are underreported.


Assuntos
Aleitamento Materno , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Recém-Nascido , Estudos Transversais , Lactação , Austrália/epidemiologia , Mães , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia
10.
Basic Clin Pharmacol Toxicol ; 131(6): 487-499, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36130042

RESUMO

Although most drugs are considered safe and compatible with breastfeeding, cases of toxic drug exposure have been reported. Active efflux transporters have been implicated as a mechanism in the transfer of drugs from mother to baby via breastmilk. Using breastmilk as a source of human mammary epithelial cells, this novel longitudinal study investigated the expression of four active transporters, namely, MDR1, MRP1, MRP2 and BCRP in the lactating human breast. BCRP gene was found to be strongly overexpressed with levels peaking at 5 months postpartum, potentially indicating a time where a breastfed infant may be at risk of inadvertent exposure to BCRP substrates. Serum albumin, a major component of human breastmilk was increasingly downregulated as lactation progresses. Xanthine oxidase/dehydrogenase, an enzyme in breastmilk attributed to a reduced risk of gastroenteritis caused by Escherichia coli and Salmonella enteritides, was downregulated. Lysozyme and fatty acid synthase are progressively upregulated. This study also shows that breastmilk-derived epithelial cells, when propagated in culture, exhibit characteristics significantly different to those derived directly from breastmilk. This serves to warn that in vitro studies are not a true representation of in vivo processes in the lactating breast; hence, application of in vitro data should be conducted with caution.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Exposição Dietética , Leite Humano , Feminino , Humanos , Lactente , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Lactação , Estudos Longitudinais , Proteínas de Neoplasias/metabolismo
11.
Philos Trans R Soc Lond B Biol Sci ; 377(1853): 20210172, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35491602

RESUMO

Research into pollinators in managed landscapes has recently combined approaches of pollination ecology and landscape ecology, because key stressors are likely to interact across wide areas. While laboratory and field experiments are valuable for furthering understanding, studies are required to investigate the interacting drivers of pollinator health and diversity across a broader range of landscapes and a wider array of taxa. Here, we use a network of 96 study landscapes in six topographically diverse regions of Britain, to test the combined importance of honeybee density, insecticide loadings, floral resource availability and habitat diversity to pollinator communities. We also explore the interactions between these drivers and the cover and proximity of semi-natural habitat. We found that among our four drivers, only honeybee density was positively related to wild pollinator abundance and diversity, and the positive association between abundance and floral resources depended on insecticide loadings and habitat diversity. By contrast, our exploratory models including habitat composition metrics revealed a complex suite of interactive effects. These results demonstrate that improving pollinator community composition and health is unlikely to be achieved with general resource enhancements only. Rather, local land-use context should be considered in fine-tuning pollinator management and conservation. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.


Assuntos
Agricultura , Inseticidas , Animais , Abelhas , Ecologia , Ecossistema , Polinização
12.
SLAS Discov ; 26(1): 151-160, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32706283

RESUMO

In drug discovery it is essential that one of the parameters tested for any new chemical entity is its affinity for human efflux systems, most notably P-glycoprotein (P-gp). These efflux systems affect not only rates of oral absorption but also rates of excretion through the liver, blood-brain barrier, and accumulation in potential target cells that upregulate efflux systems. Current methods to determine drugs' P-gp transport potential include in vitro bidirectional transport studies, and the two most common cell lines used are Caco2 and MDR1-transfected MDCK models. Caco2 cells are human but slow growing and require more than 3 weeks to mature, while MDCK cells are canine, but when transfected with human P-gp become a rapid model of P-gp affinity. Our laboratory has generated a Caco2 subclone called CLEFF4 that is fully human, yet now approaches the rapid nature of the MDCK model. No special medium is required. We have shown, in as little as 5 days postseeding, high transepithelial electrical resistance values of more than 1000 Ω·cm2 plus P-gp expression more than threefold higher than that of 21-day-old cells. Currently tested drugs included rhodamine 123 (Rh123), vinblastine, and doxorubicin, and all drugs exhibited P-gp-mediated efflux that was inhibited by PSC833. By day 6, bidirectional transport of Rh123 was as potent as that of mature Caco2 cells, for use in comparative P-gp affinity studies. We now have a human P-gp model that is rapid and works without any need for special accelerating medium. We believe this could be a welcome addition to the testing regime of new chemical entities.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Bioensaio/métodos , Descoberta de Drogas/métodos , Ativação do Canal Iônico/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Animais , Transporte Biológico , Técnicas de Cultura de Células , Linhagem Celular , Humanos
13.
J Pharmacol Sci ; 113(4): 315-24, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20724802

RESUMO

This study was conducted to determine the rate of P-glycoprotein (P-gp)-mediated efflux of digoxin analogues and metabolites and to assess the effects of macrolide antibiotics on this efflux. Bidirectional transport studies were conducted using our Caco-2 sub clone with high P-gp expression (CLEFF9). HPLC methods were employed to measure drug transport. All digoxin metabolites were P-gp substrates, although digoxin had the greatest efflux ratio. Erythromycin had no effect on the transport of digoxin, maintaining a basolateral to apical efflux ratio of 14.8, although it did reduce the efflux ratio of dihydrodigoxin and digoxigenin by 34% and 43%, respectively. Azithromycin also had little effect on the transport of digoxin or any of its metabolites. In contrast, clarithromycin and roxithromycin almost eliminated basolateral targeted efflux. Using paclitaxel as a known P-gp substrate, erythromycin demonstrated only partial P-gp inhibitory capacity, maintaining an efflux ratio over 100. In contrast, clarithromycin and roxithromycin were 10-fold greater P-gp inhibitors. Clarithromycin and roxithromycin are likely to exhibit drug interactions with digoxin via inhibition of efflux mechanisms. Azithromycin appears to have little influence on P-gp-mediated digoxin absorption or excretion and would be the safest macrolide to use concurrently with oral digoxin.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antibacterianos/farmacologia , Digoxina/farmacocinética , Macrolídeos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Células CACO-2 , Cromatografia Líquida de Alta Pressão , Humanos , Limite de Detecção
14.
Emerg Top Life Sci ; 4(5): 453-462, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-32756868

RESUMO

Invasive alien species (IAS) are one of the most severe threats to biodiversity and are the subject of varying degrees of surveillance activity. Predictive early warning systems (EWS), incorporating automated surveillance of relevant dataflows, warning generation and dissemination to decision makers are a key target for developing effective management around IAS, alongside more conventional early detection and horizon scanning technologies. Sophisticated modelling frameworks including the definition of the 'risky' species pool, and pathway analysis at the macro and micro-scale are increasingly available to support decision making and to help prioritise risks from different regions and/or taxa. The main challenges in constructing such frameworks, to be applied to border inspections, are (i) the lack of standardisation and integration of the associated complex digital data environments and (ii) effective integration into the decision making process, ensuring that risk information is disseminated in an actionable way to frontline surveillance staff and other decision makers. To truly achieve early warning in biosecurity requires close collaboration between developers and end-users to ensure that generated warnings are duly considered by decision makers, reflect best practice, scientific understanding and the working environment facing frontline actors. Progress towards this goal will rely on openness and mutual understanding of the role of EWS in IAS risk management, as much as on developments in the underlying technologies for surveillance and modelling procedures.


Assuntos
Biodiversidade , Espécies Introduzidas , Humanos , Gestão de Riscos
15.
Eur J Pharmacol ; 592(1-3): 7-12, 2008 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-18638470

RESUMO

The purpose of this study was to investigate possible efflux mechanisms involved in amphetamine derivative transport such as for 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyethylamphetamine (MDEA), para-methoxyamphetamine (p-MA), dexamphetamine and pseudoephedrine, especially across pH gradients that exist in intestinal or kidney transport. This was determined using our Caco-2 subclone, CLEFF9. Transport of the amphetamine derivatives was evaluated at pH 7.4 and pH 6/7.4+/-efflux inhibitors. Na+-H+ transporter inhibition via carbonyl cyanide-4-trifluoromethoxy phenylhydrazone (FCCP), and metabolic inhibition using Na-azide and Na-orthovanadate were also conducted, as well as using noradrenalin, adrenalin and other inhibitors of a range of carrier mediated transport systems such as histamine, organic cation transporters and dopamine carrier systems. At pH 7.4, the rate of transport for dexamphetamine, pseudoephedrine and MDMA in both apical to basolateral and reverse directions was all very rapid, confirming extensive passive diffusion at systemic pH. However, creating a pH 6.0/7.4 gradient showed marked increase in basolateral to apical transport of all amphetamines tested, with dexamphetamine, MDEA, MDMA and p-MA having a net efflux ratio of around 16, 14, 13 and 11 respectively and this was not reversed with P-glycoprotein inhibitors. Azide, FCCP, adrenalin, noradrenalin and reserpine were able to reduce the efflux by 2 to 3 fold, although tetraethylammonium could not. This suggested that extraneuronal monoamine transporters (hEMT) could be involved. This data suggests that elevated endogenous adrenalin levels may reduce amphetamine removal from the body based on these in vitro studies. Also, the use of stomach acid lowering drugs could result in more rapid systemic uptake of these amphetamine derivatives.


Assuntos
Metanfetamina/análogos & derivados , Metanfetamina/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Amilorida/farmacologia , Transporte Biológico Ativo/efeitos dos fármacos , Células CACO-2 , Cromatografia Líquida de Alta Pressão , Ciclosporinas/farmacologia , Diuréticos/farmacologia , Epinefrina/farmacologia , Corantes Fluorescentes , Humanos , Concentração de Íons de Hidrogênio , Norepinefrina/farmacologia
16.
J Am Acad Dermatol ; 58(6): 990-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18359127

RESUMO

BACKGROUND: Intermittent dosing of a topical calcineurin inhibitor for preventing atopic dermatitis (AD) disease relapse in patients with stabilized AD has not been evaluated. OBJECTIVE: We sought to evaluate the long-term efficacy and safety of 3-times-weekly use of tacrolimus ointment in preventing AD disease relapse. METHODS: Adult and pediatric patients with moderate to severe AD who were clear of disease after up to 16 weeks of treatment with tacrolimus ointment were randomized in a double-blind fashion to 3-times-weekly treatment with either tacrolimus ointment (0.03% or 0.1%) or vehicle for 40 weeks. The primary end point was the number of flare-free treatment days. RESULTS: A total of 125 patients were randomized to tacrolimus and 72 patients to vehicle. The mean number of flare-free treatment days was 177 for tacrolimus and 134 for vehicle (P = .003). Median time to first relapse was 169 days for tacrolimus and 43 for vehicle (P = .037). LIMITATIONS: Generalizability to all patients seen in clinic may be limited because only patients who responded to tacrolimus ointment in the stabilization phase were randomized into the maintenance phase of the trial. CONCLUSIONS: Maintenance therapy with tacrolimus ointment was associated with significantly more flare-free days compared with vehicle, and a significantly longer time until first disease relapse.


Assuntos
Dermatite Atópica/prevenção & controle , Imunossupressores/administração & dosagem , Tacrolimo/administração & dosagem , Adolescente , Criança , Pré-Escolar , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Pomadas , Fatores de Tempo
17.
Life Sci ; 207: 138-144, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29857072

RESUMO

AIMS: Many gastrointestinal cell lines including Caco-2, LS174T and RKO require foetal calf serum (FCS) in culture medium. However, when isolating secreted product from conditioned medium (CM), after cell exposure to a trigger, it is better to remove FCS in the culture medium for identification of secreted products of interest. However, it is unknown whether defined medium adversely affects active efflux protein expression and tight junction formation. MATERIALS AND METHODS: Using different gastrointestinal cell lines chosen with different levels of efflux transporter expression, fully defined components, such as using transferrin, insulin, selenium and ethanolamine without FCS or with a reduced percentage of FCS (2%) were tested as an optimal choice for cell growth. In addition to morphological characteristics, the expression of the ABC efflux transporters, ABCB1 (P-glycoprotein [P-gp]), ABCC2 (multidrug resistance associated protein 2), ABCG2 (breast cancer resistance protein) and occludin was determined. KEY FINDINGS: The cells required a minimum of 2% FCS for expression of transporters. Fully defined medium with no serum adversely affected the expression of transporters, especially P-gp. An important characteristic of Caco-2 cells is its ability to form tight junctions. Caco-2 did not form adequate tight junctions without 10% FCS added in the medium, as evidenced by low TEER values and reduced occluding immunohistochemistry. SIGNIFICANCE: FCS is required for efflux protein expression and tight junction generation. Nevertheless, it is possible to use 5 fold less FCS which assists with low molecular weight secretion isolation. Passage number also contributes significantly to the presence of these transporters.


Assuntos
Meios de Cultivo Condicionados/química , Meios de Cultura/química , Trato Gastrointestinal/metabolismo , Regulação da Expressão Gênica , Junções Íntimas/metabolismo , Albuminas/química , Transporte Biológico , Células CACO-2 , Linhagem Celular , Perfilação da Expressão Gênica , Células HeLa , Humanos , Proteínas de Membrana Transportadoras/metabolismo , Proteína 2 Associada à Farmacorresistência Múltipla , Permeabilidade , Ligação Proteica
18.
J Drug Target ; 14(5): 291-300, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16882549

RESUMO

A variety of anti-epileptic drugs (AEDs) were tested for their ability to be transported by P-glycoprotein (P-gp) through Caco-2 monolayers using bi-directional (apical (Ap) to basolateral (Bas), and Bas to Ap) studies. Transport rates were equivalent in both directions for vigabatrin, gabapentin, phenobarbitone, lamotrigine and carbamazepine, being 0.7 x 10- 6, 0.1 x 10- 6, 34 x 10- 6, 36 x 10- 6 and 55 x 10- 6 cm/s, respectively. Phenytoin displayed a 20% increase in Ap to Bas transport, while topiramate and ethosuximide each had greater transport in the uptake direction, with both drugs showing no efflux. None of the transport rates for these drugs were affected by P-gp inhibitors. However, the efflux rate for acetazolamide was 3-fold higher than its uptake and this was significantly reduced by P-gp inhibitors. Thus, only one anti-epileptic, acetazolamide, was shown to be weak P-gp substrate, suggesting that P-gp efflux may not be a factor in relation to the development of resistance of epilepsy therapy.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Anticonvulsivantes/farmacologia , Transporte Biológico , Células CACO-2 , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos
19.
PLoS One ; 11(4): e0152677, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27045516

RESUMO

The combination of passive drug permeability, affinity for uptake and efflux transporters as well as gastrointestinal metabolism defines net drug absorption. Efflux mechanisms are often overlooked when examining the absorption phase of drug bioavailability. Knowing the affinity of antimalarials for efflux transporters such as P-glycoprotein (P-gp) may assist in the determination of drug absorption and pharmacokinetic drug interactions during oral absorption in drug combination therapies. Concurrent administration of P-gp inhibitors and P-gp substrate drugs may also result in alterations in the bioavailability of some antimalarials. In-vitro Caco-2 cell monolayers were used here as a model for potential drug absorption related problems and P-gp mediated transport of drugs. Artemisone had the highest permeability at around 50 x 10(-6) cm/sec, followed by amodiaquine around 20 x 10(-6) cm/sec; both mefloquine and artesunate were around 10 x 10(-6) cm/sec. Methylene blue was between 2 and 6 x 10(-6) cm/sec depending on the direction of transport. This 3 fold difference was able to be halved by use of P-gp inhibition. MRP inhibition also assisted the consolidation of the methylene blue transport. Mefloquine was shown to be a P-gp inhibitor affecting our P-gp substrate, Rhodamine 123, although none of the other drugs impacted upon rhodamine123 transport rates. In conclusion, mefloquine is a P-gp inhibitor and methylene blue is a partial substrate; methylene blue may have increased absorption if co-administered with such P-gp inhibitors. An upregulation of P-gp was observed when artemisone and dihydroartemisinin were co-incubated with mefloquine and amodiaquine.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antimaláricos/farmacocinética , Regulação para Cima/efeitos dos fármacos , Antimaláricos/farmacologia , Transporte Biológico Ativo/efeitos dos fármacos , Células CACO-2 , Humanos , Azul de Metileno/farmacocinética , Azul de Metileno/farmacologia , Rodamina 123/farmacocinética , Rodamina 123/farmacologia
20.
Nat Commun ; 7: 12459, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27529661

RESUMO

Wild bee declines have been ascribed in part to neonicotinoid insecticides. While short-term laboratory studies on commercially bred species (principally honeybees and bumblebees) have identified sub-lethal effects, there is no strong evidence linking these insecticides to losses of the majority of wild bee species. We relate 18 years of UK national wild bee distribution data for 62 species to amounts of neonicotinoid use in oilseed rape. Using a multi-species dynamic Bayesian occupancy analysis, we find evidence of increased population extinction rates in response to neonicotinoid seed treatment use on oilseed rape. Species foraging on oilseed rape benefit from the cover of this crop, but were on average three times more negatively affected by exposure to neonicotinoids than non-crop foragers. Our results suggest that sub-lethal effects of neonicotinoids could scale up to cause losses of bee biodiversity. Restrictions on neonicotinoid use may reduce population declines.


Assuntos
Abelhas/fisiologia , Brassica rapa/efeitos dos fármacos , Brassica rapa/parasitologia , Neonicotinoides/farmacologia , Polinização/efeitos dos fármacos , Algoritmos , Animais , Teorema de Bayes , Abelhas/classificação , Inglaterra , Geografia , Inseticidas/farmacologia , Dinâmica Populacional , Especificidade da Espécie
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