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1.
Molecules ; 28(11)2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37298889

RESUMEN

The body's normal immune response against any invading pathogen that causes infection in the body results in inflammation. The sudden transformation in inflammation leads to the rise of inflammatory diseases such as chronic inflammatory bowel disease, autoimmune disorders, and colorectal cancer (different types of cancer develop at the site of chronic infection and inflammation). Inflammation results in two ways: short-term inflammation i.e., non-specific, involves the action of various immune cells; the other results in long-term reactions lasting for months or years. It is specific and causes angiogenesis, fibrosis, tissue destruction, and cancer progression at the site of inflammation. Cancer progression relies on the interaction between the host microenvironment and tumor cells along with the inflammatory responses, fibroblast, and vascular cells. The two pathways that have been identified connecting inflammation and cancer are the extrinsic and intrinsic pathways. Both have their own specific role in linking inflammation to cancer, involving various transcription factors such as Nuclear factor kappa B, Activator of transcription, Single transducer, and Hypoxia-inducible factor, which in turn regulates the inflammatory responses via Soluble mediators cytokines (such as Interleukin-6, Hematopoietin-1/Erythropoietin, and tumor necrosis factor), chemokines (such as Cyclooxygenase-2, C-X-C Motif chemokines ligand-8, and IL-8), inflammatory cells, cellular components (such as suppressor cells derived from myeloid, tumor-associated macrophage, and acidophils), and promotes tumorigenesis. The treatment of these chronic inflammatory diseases is challenging and needs early detection and diagnosis. Nanotechnology is a booming field nowadays for its rapid action and easy penetration inside the infected destined cells. Nanoparticles are widely classified into different categories based on their different factors and properties such as size, shape, cytotoxicity, and others. Nanoparticles emerged as excellent with highly progressive medical inventions to cure diseases such as cancer, inflammatory diseases, and others. Nanoparticles have shown higher binding capacity with the biomolecules in inflammation reduction and lowers the oxidative stress inside tissue/cells. In this review, we have overall discussed inflammatory pathways that link inflammation to cancer, major inflammatory diseases, and the potent action of nanoparticles in chronic inflammation-related diseases.


Asunto(s)
Inflamación , Neoplasias , Humanos , Inflamación/tratamiento farmacológico , Neoplasias/metabolismo , Citocinas/metabolismo , FN-kappa B/metabolismo , Quimiocinas , Microambiente Tumoral
2.
Pharmaceutics ; 15(5)2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-37242623

RESUMEN

The blood-brain barrier (BBB) is a highly sophisticated system with the ability to regulate compounds transporting through the barrier and reaching the central nervous system (CNS). The BBB protects the CNS from toxins and pathogens but can cause major issues when developing novel therapeutics to treat neurological disorders. PLGA nanoparticles have been developed to successfully encapsulate large hydrophilic compounds for drug delivery. Within this paper, we discuss the encapsulation of a model compound Fitc-dextran, a large molecular weight (70 kDa), hydrophilic compound, with over 60% encapsulation efficiency (EE) within a PLGA nanoparticle (NP). The NP surface was chemically modified with DAS peptide, a ligand that we designed which has an affinity for nicotinic receptors, specifically alpha 7 nicotinic receptors, found on the surface of brain endothelial cells. The attachment of DAS transports the NP across the BBB by receptor-mediated transcytosis (RMT). Assessment of the delivery efficacy of the DAS-conjugated Fitc-dextran-loaded PLGA NP was studied in vitro using our optimal triculture in vitro BBB model, which successfully replicates the in vivo BBB environment, producing high TEER (≥230 ) and high expression of ZO1 protein. Utilising our optimal BBB model, we successfully transported fourteen times the concentration of DAS-Fitc-dextran-PLGA NP compared to non-conjugated Fitc-dextran-PLGA NP. Our novel in vitro model is a viable method of high-throughput screening of potential therapeutic delivery systems to the CNS, such as our receptor-targeted DAS ligand-conjugated NP, whereby only lead therapeutic compounds will progress to in vivo studies.

3.
Nanomedicine (Lond) ; 17(30): 2245-2264, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36975758

RESUMEN

Diagnosis and treatment of lung diseases pose serious challenges. Currently, diagnostic as well as therapeutic methods show poor efficacy toward drug-resistant bacterial infections, while chemotherapy causes toxicity and nonspecific delivery of drugs. Advanced treatment methods that cure lung-related diseases, by enabling drug bioavailability via nasal passages during mucosal formation, which interferes with drug penetration to targeted sites, are in demand. Nanotechnology confers several advantages. Currently, different nanoparticles, or their combinations, are being used to enhance targeted drug delivery. Nanomedicine, a combination of nanoparticles and therapeutic agents, that delivers drugs to targeted sites increases the bioavailability of drugs at these sites. Thus, nanotechnology is superior to conventional chemotherapeutic strategies. Here, the authors review the latest advancements in nanomedicine-based drug-delivery methods for managing acute and chronic inflammatory lung diseases.


Asunto(s)
Enfermedades Pulmonares , Nanopartículas , Humanos , Nanomedicina/métodos , Sistemas de Liberación de Medicamentos/métodos , Nanotecnología/métodos , Preparaciones Farmacéuticas , Pulmón , Enfermedades Pulmonares/tratamiento farmacológico
4.
Life (Basel) ; 11(10)2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-34685393

RESUMEN

Alzheimer's disease (AD) is a significant health concern with enormous social and economic impact globally. The gradual deterioration of cognitive functions and irreversible neuronal losses are primary features of the disease. Even after decades of research, most therapeutic options are merely symptomatic, and drugs in clinical practice present numerous side effects. Lack of effective diagnostic techniques prevents the early prognosis of disease, resulting in a gradual deterioration in the quality of life. Furthermore, the mechanism of cognitive impairment and AD pathophysiology is poorly understood. Microfluidics exploits different microscale properties of fluids to mimic environments on microfluidic chip-like devices. These miniature multichambered devices can be used to grow cells and 3D tissues in vitro, analyze cell-to-cell communication, decipher the roles of neural cells such as microglia, and gain insights into AD pathophysiology. This review focuses on the applications and impact of microfluidics on AD research. We discuss the technical challenges and possible solutions provided by this new cutting-edge technique to understand disease-associated pathways and mechanisms.

5.
Nanomedicine (Lond) ; 16(21): 1905-1923, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34348474

RESUMEN

The increasing burden of respiratory diseases caused by microbial infections poses an immense threat to global health. This review focuses on the various types of biofilms that affect the respiratory system and cause pulmonary infections, specifically bacterial biofilms. The article also sheds light on the current strategies employed for the treatment of such pulmonary infection-causing biofilms. The potential of nanocarriers as an effective treatment modality for pulmonary infections is discussed, along with the challenges faced during treatment and the measures that may be implemented to overcome these. Understanding the primary approaches of treatment against biofilm infection and applications of drug-delivery systems that employ nanoparticle-based approaches in the disruption of biofilms are of utmost interest which may guide scientists to explore the vistas of biofilm research while determining suitable treatment modalities for pulmonary respiratory infections.


Asunto(s)
Nanopartículas , Preparaciones Farmacéuticas , Antibacterianos/uso terapéutico , Biopelículas , Sistemas de Liberación de Medicamentos , Pulmón
6.
Nanomedicine (Lond) ; 16(20): 1763-1773, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34296625

RESUMEN

Aim: This study was aimed at evaluating the anticancer potential of curcumin-loaded poly(lactic-co-glycolic acid) (PLGA) based nanoparticles (NPs) in MDA-MB231 human breast cancer cells. Methods: Curcumin-loaded PLGA NPs were developed using a modified solvent evaporation technique. Physical characterization was performed on the formulated NPs. Furthermore, in vitro experiments were conducted to study the biological activity of the curcumin-loaded NPs. Results: Curcumin-loaded PLGA NPs demonstrated high encapsulation efficiency and sustained payload release. Moreover, the NPs exhibited a significant reduction in cell viability, cell migration and cell invasion in the MDA-MB231 cells. Conclusion: The study revealed that the formulated curcumin-loaded PLGA NPs possessed significant anti-metastatic properties. The findings showcased the possible potential of curcumin-loaded NPs in the management of debilitating conditions such as cancer. In addition, this study could form the basis for further research and advancements in this area.


Asunto(s)
Neoplasias de la Mama , Curcumina , Nanopartículas , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Curcumina/farmacología , Portadores de Fármacos , Femenino , Glicoles , Humanos , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
7.
Sci Rep ; 10(1): 21409, 2020 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-33293559

RESUMEN

Measuring animal stress is fundamentally important for assessing animal emotional state and welfare. Conventional methods of quantifying stress (cortisol levels, heart rate/heart rate variability) require specialist equipment and are not instantly available. Spontaneous blink rate (SBR) has previously been used to measure stress responses in humans and may provide a non-invasive method for measuring stress in other animal species. Here we investigated the use of SBR as a measure of stress in the domestic horse. SBR was measured before and during a low-stress event (sham clipping) and compared with heart rate variability and salivary cortisol. For the entire sample, there was a reduction in SBR (startle response) during the first minute of clipping. For horses reactive to clipping, the initial reduction in SBR was followed by an increase above baseline whereas the SBR of the non-reactive horses quickly returned to baseline. For the entire sample, SBR correlated with heart rate variability and salivary cortisol. We have demonstrated that SBR is a valid fast alternative measure of stress in horses, but the initial 'startle' response must be considered when using this parameter as a measure of animal stress.


Asunto(s)
Atención/fisiología , Parpadeo , Estrés Psicológico/diagnóstico , Animales , Conducta Animal/fisiología , Caballos , Hidrocortisona/análisis , Modelos Animales , Saliva/química , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatología
8.
Health Care Anal ; 27(4): 289-308, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30895412

RESUMEN

The term "effective," on its own, is honorific but vague. Interventions against serious mental illness may be "effective" at goals as diverse as reducing "apparent sadness" or providing housing. Underexamined use of "effective" and other success terms often obfuscates differences and incompatibilities in interventions, degrees of effectiveness, key omissions in effectiveness standards, and values involved in determining what counts as "effective." Yet vague use of such success terms is common in the research, clinical, and policy realms, with consequences that negatively affect the care offered to individuals experiencing serious mental illness. A pragmatist-oriented solution to these problems suggests that when people use success terms, they need to explain and defend the goals and supporting values embedded in the terms, asking and answering the questions, "Effective at what? For whom? How effective? And why that goal?" Practical and epistemic standards for effectiveness will likely remain plural for good reasons, but each standard should be well explained and well justified.


Asunto(s)
Objetivos , Trastornos Mentales/terapia , Psiquiatría , Psicología , Humanos
9.
J Drug Target ; 27(9): 959-970, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30623678

RESUMEN

In recent years, rabies virus-derived peptide (RDP) has shown promise as a specific neural cell targeting ligand, however stability of the peptide in human serum was unknown. Herein, we report the molecular modelling and design of an optimised peptide sequence based on interactions of RDP with the α7 subunit of the nicotinic acetylcholine receptor (nAChR). The new sequence, named DAS, designed around a 5-mer sequence which demonstrated optimal nAChR binding in silico, showed greatly improved stability for up to 8 hours in human serum in comparison to RDP, which degraded within 2 hours at 37 °C. In vitro analysis using SH-SY5Y neuroblastoma cells showed that DAS-conjugated nanoparticles containing the cytotoxic drug doxorubicin (DAS-Dox-NP) displayed significantly enhanced cytotoxicity compared with untargeted doxorubicin-loaded nanoparticles (Dox-NP). DAS-Dox-NP had no significant effect on non-neural cell types, confirming its neural-specific targeting properties. In this manuscript, we report the design and testing of an optimised peptide ligand, conjugated to a nanoparticulate delivery vehicle and specifically targeted to neural cells. Future impact of an innovative targeting peptide ligand combining the ability to selectively identify the target and facilitate cellular internalisation could enable the successful treatment of many neural cell disorders.


Asunto(s)
Sistemas de Liberación de Medicamentos , Glicoproteínas/administración & dosificación , Nanopartículas , Neuroblastoma/tratamiento farmacológico , Fragmentos de Péptidos/administración & dosificación , Proteínas Virales/administración & dosificación , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular , Línea Celular Tumoral , Simulación por Computador , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacología , Glicoproteínas/química , Glicoproteínas/farmacología , Humanos , Masculino , Modelos Moleculares , Neuroblastoma/patología , Fragmentos de Péptidos/química , Fragmentos de Péptidos/farmacología , Factores de Tiempo , Proteínas Virales/química , Proteínas Virales/farmacología , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
10.
Pharm Res ; 36(2): 26, 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30560466

RESUMEN

BACKGROUND: Overexpression of the RAN GTP (RAN) gene has been shown to be linked to metastatic activity of MDA-MB231 human breast cancer cells by increasing Ras/MEK/ERK and PI3K/Akt/mTORC1 signalling. The aim of this study was to investigate the potential of polymeric nanoparticles to deliver two novel shRNA sequences, targeted against the RAN gene, to MDA-MB231 cells grown in culture and to assess their effects in a range of biological assays. METHODS: Biodegradable PLGA nanoparticles, loaded with shRNA-1 and shRNA-4, were fabricated using a double emulsion solvent evaporation technique and characterised for size, zeta potential and polydispersity index before testing on the MDA-MB231 cell line in a range of assays including cell viability, migration, invasion and gene knock down. RESULTS: shRNA-loaded nanoparticles were successfully fabricated and delivered to MDA-MB231 cells in culture, where they effectively released their payload, causing a decrease in both cell invasion and cell migration by knocking down RAN gene expression. CONCLUSION: Results indicate the anti-RAN shRNA-loaded nanoparticles deliver and release biological payload to MDA-MB231 cells in culture. This works paves the way for further investigations into the possible use of anti-RAN shRNA-loaded NP formulations for the treatment of breast cancer in vivo.


Asunto(s)
Portadores de Fármacos/química , Nanopartículas/química , Poliglactina 910/química , ARN Interferente Pequeño/genética , Neoplasias de la Mama , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Composición de Medicamentos , Liberación de Fármacos , Femenino , Técnicas de Silenciamiento del Gen , Técnicas de Transferencia de Gen , Humanos , Tamaño de la Partícula , ARN Interferente Pequeño/farmacología , Propiedades de Superficie
11.
Acta Biomater ; 80: 327-340, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30201433

RESUMEN

Combination cancer chemotherapy provides an important treatment tool, both as an adjuvant and neoadjuvant treatment, this shift in focus from mono to combination therapies has led to increased interest in drug delivery systems (DDS). DDSs, such as polymersomes, are capable of encapsulating large amounts of multiple drugs with both hydrophilic and hydrophobic properties simultaneously, as well as offering a mechanism to combat multi drug resistant cancers and poor patient tolerance of the cytotoxic compounds utilised. In this article, we report the formulation and evaluation of a novel electroneutral polymersome capable of high encapsulation efficacies for multiple drugs (Doxorubicin, 5-Fluorouracil and leucovorin). The in-vivo biodistribution of the polymersome were established and they were found to accumulate largely in tumour tissue. Polymersome encapsulating the three chemotherapeutic drugs were assessed both in-vitro (BxPC-3 cell line) and in-vivo (following intratumoral and intravenous administration) and compared with the same concentration of the three drugs in solution. We report better efficacy and higher maximum tolerated dose for our combination drug loaded polymersomes in all experiments. Furthermore, intratumorally injected combination drug loaded polymersomes exhibited a 62% reduction in tumour volume after 13 days when compared with the free combination solutions. A smaller differential of 13% was observed for when treatment was administered intravenously however, importantly less cardiotoxicity was displayed from the polymersomal DDS. In this study, expression of a number of survival-relevant genes in tumours treated with the free chemotherapy combination was compared with expression of those genes in tumours treated with the polymersomes harbouring those drugs and the significance of findings is discussed. STATEMENT OF SIGNIFICANCE: The shift in focus from mono to combination chemotherapies has led to an increased interest in the role of drug delivery systems (DDS). Liposomes, although commercialized for mono therapy, have lower loading capacities and stability than their polymeric counterpart, polymersomes. Polymersomes are growing in prevalence as their advantageous properties are better understood and exploited. Here we present a novel polymersome for the encapsulation of three anticancer compounds. This is the first time this particular polymersome has been used to encapsulate these three compounds with both an in-vitro and in-vivo evaluation carried out. This work will be of interest to those in the field of combination therapy, drug delivery, drug toxicity, multidrug resistance, liposomes, DDS and polymersomes.


Asunto(s)
Electricidad , Neoplasias/tratamiento farmacológico , Polímeros/química , Línea Celular Tumoral , Supervivencia Celular , Liberación de Fármacos , Quimioterapia Combinada , Regulación Neoplásica de la Expresión Génica , Humanos , Inyecciones Intravenosas , Neoplasias/patología , Polímeros/toxicidad , Distribución Tisular , Carga Tumoral/efectos de los fármacos , Imagen de Cuerpo Entero
12.
Eur J Pharm Sci ; 114: 372-384, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29288081

RESUMEN

We describe the development of a nanoparticulate system, with variation of poly(ethylene glycol) (PEG) content, capable of releasing therapeutic levels of bioactive insulin for extended periods of time. Recombinant human insulin was encapsulated in poly(d,l-lactide-co-glycolide) nanoparticles, manufactured with variation in poly(ethylene glycol) content, and shown to be stable for 6days using SDS-PAGE, western blot and MALDI MS. To determine if insulin released from this sustained release matrix could stimulate migration of cell types normally active in dermal repair, a model wound was simulated by scratching confluent cultures of human keratinocytes (HaCaT) and fibroblasts (Hs27). Although free insulin was shown to have proliferative effect, closure of in vitro scratch fissures was significantly faster following administration of nano-encapsulated insulin. This effect was more pronounced in HaCaT cells when compared to Hs27 cells. Variation in PEG content had the greatest effect on NP size, with a lesser influence on scratch closure times. Our work supports a particulate uptake mechanism that provides for intracellular insulin delivery, leading to enhanced cell proliferation. When placed into an appropriate topical delivery vehicle, such as a hydrogel, the extended and sustained topical administration of active insulin delivered from a nanoparticulate vehicle shows promise in promoting tissue healing.


Asunto(s)
Citoplasma/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Insulina/metabolismo , Nanopartículas/metabolismo , Polietilenglicoles/metabolismo , Cicatrización de Heridas/efectos de los fármacos , Administración Cutánea , Línea Celular , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Citoplasma/efectos de los fármacos , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/metabolismo , Liberación de Fármacos/efectos de los fármacos , Liberación de Fármacos/fisiología , Estabilidad de Medicamentos , Humanos , Insulina/administración & dosificación , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Nanopartículas/administración & dosificación , Polietilenglicoles/administración & dosificación , Cicatrización de Heridas/fisiología
13.
Int J Pharm ; 525(1): 12-20, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28412449

RESUMEN

Drug delivery to the brain is still a major challenge in the field of therapeutics, especially for large and hydrophilic compounds. In order to achieve drug delivery of therapeutic concentration in the central nervous system, the problematic blood brain barrier (BBB) must be overcome. This work presents the formulation of a targeted nanoparticle-based drug delivery system using a specific neural cell targeting ligand, rabies virus derived peptide (RDP). Characterization studies revealed that RDP could be conjugated to drug-loaded PLGA nanoparticles of average diameter 257.10±22.39nm and zeta potential of -5.51±0.73mV. In vitro studies showed that addition of RDP to nanoparticles enhanced drug accumulation in a neural cell line specifically as opposed to non-neural cell lines. It was revealed that this drug delivery system is reliant upon nicotinic acetylcholine receptor (nAChR) function for RDP-facilitated effects, supporting a cellular uptake mechanism of action. The specific neural cell targeting capabilities of RDP via the nAChR offers a non-toxic, non-invasive and promising approach to the delivery of therapeutics to the brain.


Asunto(s)
Barrera Hematoencefálica , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Neuronas/efectos de los fármacos , Receptores Nicotínicos/metabolismo , Línea Celular Tumoral , Doxorrubicina/administración & dosificación , Liberación de Fármacos , Humanos , Péptidos/administración & dosificación , Virus de la Rabia , Proteínas Virales/administración & dosificación
14.
J Drug Target ; 25(5): 379-385, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27581650

RESUMEN

Rabies virus glycoprotein (RVG), a 505 amino acid type-1 glycoprotein, is responsible for the neurotrophic nature of the rabies virus infection. Despite varying reports in the literature as to which receptor is ultimately responsible for interaction of RVG with the nervous system, there is a strong argument for major nicotinic acetylcholine receptor (nAChR) involvement. Peptide derivatives of RVG, such as rabies virus-derived peptide (RDP) and RVG-29 are emerging as promising targeting ligands for the delivery of therapeutics to the central nervous system (CNS). The neurotrophic nature of RVG and indeed its derivatives may be due to interaction with ubiquitous nAChRs principally, but also association with other neural cell-specific molecules such as neural cell adhesion molecule (NCAM). It is possible that nAChR-mediated uptake of RVG-derived peptides may serve as an attractive new approach for targeting drug delivery to the brain. Potential application of this type of drug delivery system extends to many diseases affecting the CNS, where specific and effective drug delivery is normally a challenging process.


Asunto(s)
Sistema Nervioso Central/metabolismo , Sistemas de Liberación de Medicamentos , Glicoproteínas/química , Péptidos/administración & dosificación , Virus de la Rabia/química , Proteínas Virales/química , Animales , Humanos , Enfermedades Neurodegenerativas/tratamiento farmacológico , Péptidos/química
15.
Med J Aust ; 205(2): 62, 2016 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-27456444
16.
Stud Hist Philos Biol Biomed Sci ; 41(1): 21-31, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20185081

RESUMEN

Many successful sciences both serve and shape human ends. Conversely, the societies in which these sciences are practiced support the research and provide interpretive context. These mutual influences may result in a positive feedback loop that reinforces constitutive and contextual values, embedding them in scientific concepts: the ADHD concept is a case in point. In an ongoing process, social considerations fuel investigational choices and contexts for evaluating data. Scientific study forwards the feedback loop through the influence of investigative trends, by directly and indirectly embedding values in data interpretation, and by core methodologies that heighten the contrast between 'ADHD' and 'normal'. The resulting scientific conclusions embed value valences in the ADHD concept; social uptake of that valenced concept begins another round of interest in its implications and support of the science. The processes at work in the ADHD case are very general, so we should expect to see similar processes and results in other fields.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Investigación Biomédica , Valores Sociales , Retroalimentación Psicológica , Humanos
17.
J Pharm Pharmacol ; 60(5): 661-6, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18416944

RESUMEN

Glycyrrhetinic acid (GA) is the active metabolite of glycyrrhizic acid, one of the components of liquorice extract. It has been shown to possess anti-inflammatory activity and to inhibit hepatic tumour growth. In this preliminary study, we have shown that GA could significantly reduce the rate of proliferation of LNCaP androgen dependent prostate cancer cells, whereas it had no effect on proliferation of PC3 and DU145 androgen-independent prostate cancer cells. Additionally, GA could significantly reduce the production of prostate-specific antigen by LNCaP cells maintained in-vitro. This study provides a sound platform for further investigation.


Asunto(s)
Ácido Glicirretínico/farmacología , Glycyrrhiza/química , Neoplasias de la Próstata/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Masculino , Extractos Vegetales/farmacología , Antígeno Prostático Específico/metabolismo , Neoplasias de la Próstata/metabolismo
18.
J Pharm Pharmacol ; 60(2): 139-44, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18237460

RESUMEN

There is currently a shifting focus towards finding natural compounds that may prevent or treat cancer, due to the problems that exist with current chemotherapeutic regimens. The fruit of the Punica granatum (pomegranate) contains hundreds of phytochemicals and pomegranate extracts have recently been shown to exhibit antioxidant properties, thought to be due to the action of ellagic acid, the main polyphenol in pomegranate. In this mini review the effects of pomegranate extracts and ellagic acid on the proliferation of prostate cancer cells and their future potential are discussed.


Asunto(s)
Ácido Elágico/farmacología , Lythraceae/química , Neoplasias de la Próstata/tratamiento farmacológico , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Ácido Elágico/aislamiento & purificación , Frutas , Humanos , Masculino , Fitoterapia , Extractos Vegetales
19.
Med Health Care Philos ; 10(2): 129-40, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17486432

RESUMEN

Use of medication for treatment of ADHD (or its historical precursors) has been debated for more than forty years. Reasons for the ongoing differences of opinion are analyzed by exploring some of the arguments for and against considering ADHD a mental disorder. Relative to two important DSM criteria - that a mental disorder causes some sort of harm to the individual and that a mental disorder is the manifestation of a dysfunction in the individual - ADHD's classification as a mental disorder is found to be contentiously value-laden. The disagreements spill over to reasoning regarding appropriate management, because justification for a drug prescription is in part predicated on the idea that the drugs manage mental disorders. These debates do not appear to be nearing resolution, so individuals offering advice, or trying to decide whether ADHD drugs are appropriate for themselves or their children, may find it helpful to compare the values underlying various perspectives with their own.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/uso terapéutico , Trastorno por Déficit de Atención con Hiperactividad/clasificación , Trastorno por Déficit de Atención con Hiperactividad/historia , Utilización de Medicamentos , Ética Médica , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Filosofía Médica
20.
Chem Biol Drug Des ; 69(3): 170-9, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17441903

RESUMEN

A series of synthetic peptides in which the C-terminal carboxyl grouping (-CO(2)H) of each has been chemically converted into a variety of ene dione derivatives (-CO-CH=CH-CO-X; X = -H, -Me, -OBut, -OEt, -OMe, -CO-OMe), have been prepared and tested as inactivators against typical members of the serine and cysteine protease families. For example, the sequences Cbz-Pro-Phe-CH=CH-CO-OEt (I) which fulfils the known primary and secondary specificity requirements of the serine protease chymotrypsin, and Cbz-Phe-Ala-CH=CH-CO-OEt (II) which represents a general recognition sequence for cysteine proteases such as cathepsins B, L and S, have been tested as putative irreversible inactivators of their respective target proteases. It was found that, whereas II, for example, functioned as a time-dependent, irreversible inactivator of each of the cysteine proteases, I behaved only as a modest competitive reversible inhibitor of chymotrypsin. Within the simple ester sequences Cbz-Phe-Ala-CH=CH-CO-R, the rank order of inhibitor effectiveness decreases in the order R = -OMe > -OEt >> -OBut. It was also found that the presence of both an unsaturated double bond and an ester (or alpha-keto ester) moiety were indispensable for obtaining irreversible inactivators. Of the irreversible inactivators synthesized, Cbz-Phe-Ala-CH=CH-CO-CO-OEt (which contains a highly electrophilic alpha-keto ester grouping) was found to be the most effective exhibiting, for example, second-order rate constants of approximately 1.7 x 10(6)M(-1)min(-1) and approximately 4.9 x 10(4)M(-1)min(-1) against recombinant human cathepsin S and human spleenic cathepsin B, respectively. This initial study thus holds out the promise that this class of inactivator may well be specific for the cysteine protease subclass.


Asunto(s)
Catepsinas/antagonistas & inhibidores , Catepsinas/metabolismo , Inhibidores de Cisteína Proteinasa/síntesis química , Inhibidores de Cisteína Proteinasa/farmacología , Péptidos/síntesis química , Péptidos/farmacología , Butiratos/química , Catálisis , Cisteína/química , Inhibidores de Cisteína Proteinasa/química , Activación Enzimática/efectos de los fármacos , Ésteres/química , Cinética , Metilación , Estructura Molecular , Nitrocompuestos/química , Péptidos/química , Relación Estructura-Actividad
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