Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Antibiotics (Basel) ; 13(5)2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38786150

RESUMO

Scorpion venom peptides are generally classified into two main groups: the disulfide bridged peptides (DBPs), which usually target membrane-associated ion channels, and the non-disulfide bridged peptides (NDBPs), a smaller group with multifunctional properties. In the past decade, these peptides have gained interest because most of them display functions that include antimicrobial, anticancer, haemolytic, and anti-inflammatory activities. Our current study focuses on the short (9-19 amino acids) antimicrobial linear scorpion peptides. Most of these peptides display a net positive charge of 1 or 2, an isoelectric point at pH 9-10, a broad range of hydrophobicity, and a Grand Average of Hydropathy (GRAVY) Value ranging between -0.05 and 1.7. These features allow these peptides to be attracted toward the negatively charged phospholipid head groups of the lipid membranes of target cells, a force driven by electrostatic interactions. This review outlines the antimicrobial potential of short-chained linear scorpion venom peptides. Additionally, short linear scorpion peptides are in general more attractive for large-scale synthesis from a manufacturing point of view. The structural and functional diversity of these peptides represents a good starting point for the development of new peptide-based therapeutics.

2.
J Pharm Policy Pract ; 17(1): 2319746, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38798765

RESUMO

Adherence constitutes an integral aspect of achieving consistently good clinical results. Understanding pharmacists' perceptions and attitudes, along with existing barriers is essential on the roadmap of enhancing patient adherence. This constitutes the goal of this study. Methodology: A validated questionnaire was sent to a sample of 280 community pharmacists. Pharmacists were notified both by email and telephone. A response rate of 55% was achieved. Results: Most pharmacists agree that the identification of patients' suboptimal adherence falls under their professional responsibility and they engage in activities to promote it. There is evidence to support that the most popular interventions were self-management and indirect methods. Specific tools were used to a lesser degree. Finally, the current study illustrated that the most commonly identified barriers were the preference of patients for physicians regarding adherence, lack of information from patients and lack of time. Conclusion: Although the important role of pharmacists in adherence is ascertained, significant discrepancies in the tools used to control and promote adherence among pharmacists were identified, and also in obstacles faced by themselves and their patients. The interventions should be more consistent and the notion of cooperation among health care professionals should be nurtured.

3.
J Pharm Policy Pract ; 16(1): 93, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37475043

RESUMO

BACKGROUND: Over-the-counter medications (OTC) are safe and effective when patients follow the patient's information leaflet (PIL) instructions and/or the instructions given by healthcare professionals (HCPs). However, OTC medications could be harmful and unsafe when individuals do not follow the given instructions and/or when their understanding about the proper use of OTC medications is incorrect. This study aimed to investigate the knowledge and perceptions of people regarding paracetamol use in the Republic of Cyprus. METHODS: This cross-sectional study, which belongs to quantitative research methods, included participants visiting community pharmacies in the following three cities of the Republic of Cyprus: Nicosia, Limassol and Larnaca. Participation in the study was voluntary and anonymous. Participants responded to the survey-based questionnaire, which concerned their knowledge and views on paracetamol use. After the data collection, responses were tabulated and analysed statistically. RESULTS: The original compound was shown to be more well-known compared to generics. A notable percentage of respondents-ranging between 13.0% (N = 49) and 29.8% (N = 112)-answered incorrectly that broadly used non-steroidal anti-inflammatory drugs (NSAIDs) contain paracetamol. Furthermore, a remarkable percentage of respondents (71.5%, N = 269 and 50.3%, N = 189, respectively) falsely believed that two widely used combination products in the market of Cyprus (Paracetamol and Hyoscine-N-butylbromide; Paracetamol and Codeine and Caffeine) did not contain paracetamol. A notable percentage of participants (27.6%, N = 100) believed that paracetamol causes low toxicity. More than a third of the respondents (40.2%, N = 149) drink alcohol together with or slightly after consuming paracetamol products. This viewpoint was linked with the participants' attitude towards consuming paracetamol medications after drinking alcohol (OR for consuming alcohol versus not consuming alcohol 0.100, 95% CI 0.044-0.225, p = 0.000). CONCLUSIONS: To the best of our knowledge, this is the first study conducted in the Republic of Cyprus on this topic. Paracetamol is frequently consumed by individuals, both in its generic and original forms. However, the study showed that respondents often misperceive NSAIDs and paracetamol-containing medications. In addition, it is identified that there is a lack of education among people about the safe and effective use of paracetamol, namely, indications, potential side effects, maximum daily dose, alcohol consumption, and the potential risks of hepatotoxicity. The study contributed to the current published literature as it showed that there is a significant public health issue, for which appropriate measures can be established by the respective Authorities of Cyprus.

4.
J Diet Suppl ; 20(6): 811-831, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36073362

RESUMO

Tribulus terrestris L. contains compounds with antioxidant and anti-inflammatory properties, but its effects on exercise-induced oxidative stress and inflammatory responses are unclear. The aim of this study was to examine whether Tribulus terrestris L. supplementation can attenuate oxidative stress and inflammatory responses to acute aerobic exercise and improve DOMS. In a randomized, double-blind, crossover design study, thirteen healthy men received either a daily supplement of Tribulus terrestris L. or a placebo for 4 weeks (2-week wash-out period between trials). Before and after the supplementation periods, participants performed an exercise test to exhaustion (75% VO2max). DOMS, thigh girth, and knee joint range of motion (KJRM) were assessed before and after the exercise (2, 24, and 48 h). Blood samples were analyzed for reduced (GSH) and oxidized (GSSG) glutathione, GSH/GSSG ratio, protein carbonyls, total antioxidant capacity, creatine kinase activity, white blood cell count, and TBARS. Acute exercise to exhaustion induced inflammatory responses and changed the blood redox status in both Tribulus and Placebo groups (p < 0.050). Tribulus terrestris L. improved GSH fall (p = 0.005), GSSG rise (p = 0.001) and maintained a higher level of GSH/GSSG ratio at the 2 h point (p = 0.034). TBARS were lowered, protein carbonyls, creatine kinase activity, and white blood cell count elevation diminished significantly (p < 0.050). Tribulus terrestris L. administration did not affect DOMS, thigh girth, or KJRM (p > 0.050). 4-weeks of Tribulus terrestris L. supplementation effectively attenuates oxidative stress responses but cannot improve DOMS.


Assuntos
Mialgia , Tribulus , Humanos , Masculino , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Creatina Quinase , Suplementos Nutricionais , Glutationa , Dissulfeto de Glutationa/metabolismo , Mialgia/tratamento farmacológico , Estresse Oxidativo , Projetos Piloto , Substâncias Reativas com Ácido Tiobarbitúrico , Tribulus/metabolismo
5.
Nutrients ; 14(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36432398

RESUMO

This systematic review with metanalysis evaluated and analyzed the beneficial effects of certain plants food in type 2 diabetes (T2D) when consumed alone or in combination with chitosan. The main objective of the paper was to examine the relation of chitosan nanogel and mixed food plant (MFP) to control T2D. The databases included Medline, Scopus, PubMed, as well as Cochrane available between the month of January 1990 to January 2021. The eligibility criteria for selecting studies were case-controlled studies that included unripe plantain, bitter yam, okra, and chitosan either used-alone or in combination with non-specified food plants (NSFP). Two-fold autonomous critics retrieved the information required and evaluated the risk of bias of involved studies. Random-effect meta-analyses on blood glucose controls, were performed. Results of 18 studies included: seven that examined unripe plantains, one bitter yam, two okras, and eight chitosan, found regarding the decrease in blood glucose level. Meta-analysis of the results found a large proportion of I2 values for all studies (98%), meaning heterogeneity. As a consequence, the combined effect sizes were not useful. Instead, prediction interval (PI) was used (mean difference 4.4 mg/dL, 95% PI -6.65 to 15.50 and mean difference 3.4 mg/dL, 95% PI -23.65 to 30.50) rather than the estimate of its confidence interval (CI). These studies were at 50% high risk of bias and 50% low risk of bias and there was judged to be an unclear risk of bias due to the insufficient information from the included study protocol (moderately low). The intervention lasted between three and 84 days, indicating potency and effectiveness of the intervention at both short and long durations. Due to the moderately low quality of the studies, the findings were cautiously interpreted. In conclusion, the current evidence available from the study does support the relation of chitosan with mixed unripe plantain, bitter yam and okra for the management of T2D. Further high-quality case-controlled animal studies are required to substantiate if indeed chitosan nanogel should be cross-linked with the specified food plant (SFP) for the management T2D.


Assuntos
Quitosana , Diabetes Mellitus Tipo 2 , Animais , Glicemia , Nanogéis , Plantas Comestíveis , Estudos Observacionais como Assunto
6.
Molecules ; 27(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35956774

RESUMO

Herein, we propose two chalcone molecules, (E)-1-(4-methoxyphenyl)-3-(p-tolyl) prop-2-en-1-one and (E)-3-(4-hydroxyphenyl)-1-(2,4,6-trihydroxyphenyl) prop-2-en-1-one, based on the anticancer bioactive molecule Xanthohumol, which are suitable for further in vitro and in vivo studies. Their ability to create stable complexes with the antiapoptotic X-linked IAP (XIAP) protein makes them promising anticancer agents. The calculations were based on ligand-based and structure-based virtual screening combined with the pharmacophore build. Additionally, the structures passed Lipinski's rule for drug use, and their reactivity was confirmed using density functional theory studies. ADMET studies were also performed to reveal the pharmacokinetic potential of the compounds. The candidates were chosen from 10,639,400 compounds, and the docking protocols were evaluated using molecular dynamics simulations.


Assuntos
Proteínas Reguladoras de Apoptose , Propiofenonas , Flavonoides , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Propiofenonas/farmacologia
7.
PLoS One ; 17(6): e0269885, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35696396

RESUMO

Monitoring the levels of IgG antibodies against the SARS-CoV-2 is important during the coronavirus disease 2019 (COVID-19) pandemic, to plan an adequate and evidence-based public health response. After this study we report that the plasma levels of IgG antibodies against SARS-CoV-2 spike protein were higher in individuals with evidence of prior infection who received at least one dose of either an mRNA-based vaccine (Comirnaty BNT162b2/Pfizer-BioNTech or Spikevax mRNA-1273/Moderna) or an adenoviral-based vaccine (Vaxzervia ChAdOx1 nCoV-19 /Oxford-Astra Zeneca) (n = 39) compared to i) unvaccinated individuals with evidence of prior infection with SARS-CoV-2 (n = 109) and ii) individuals without evidence of prior infection with SARS-CoV-2 who received one or two doses of one of the aforementioned vaccines (n = 342). Our analysis also revealed that regardless of the vaccine technology (mRNA-based and adenoviral vector-based) two doses achieved high anti- SARS-CoV-2 IgG responses. Our results indicate that vaccine-induced responses lead to higher levels of IgG antibodies compared to those produced following infection with the virus. Additionally, in agreement with previous studies, our results suggest that among individuals previously infected with SARS-CoV-2, even a single dose of a vaccine is adequate to elicit high levels of antibody response.


Assuntos
COVID-19 , Vacinas Virais , Anticorpos Antivirais , Vacina BNT162 , COVID-19/epidemiologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , Chipre , Humanos , Imunoglobulina G , RNA Mensageiro , SARS-CoV-2 , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus
8.
Pharmaceutics ; 14(1)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35057029

RESUMO

Fibrillar structures derived from plant or animal origin have long been a source of inspiration for the design of new biomaterials. The Asn-Gly-Ile-Trp-Tyr-NH2 (NGIWY-amide) pentapeptide, isolated from the sea cucumber Apostichopus japonicus, which spontaneously self-assembles in water to form hydrogel, pertains to this category. In this study, we evaluated this ultra-short cosmetic bioinspired peptide as vector for local drug delivery applications. Combining nuclear magnetic resonance, circular dichroism, infrared spectroscopy, X-ray diffraction, and rheological studies, the synthesized pentapeptide formed a stiff hydrogel with a high ß-sheet content. Molecular dynamic simulations aligned well with scanning electron and atomic-force microscopy studies, revealing a highly filamentous structure with the fibers adopting a helical-twisted morphology. Model dye localization within the supramolecular hydrogel provided insights on the preferential distribution of hydrophobic and hydrophilic compounds in the hydrogel network. That was further depicted in the diffusion kinetics of drugs differing in their aqueous solubility and molecular weight, namely, doxorubicin hydrochloride, curcumin, and octreotide acetate, highlighting its versatility as a delivery vector of both hydrophobic and hydrophilic compounds of different molecular weight. Along with the observed cytocompatibility of the hydrogel, the NGIWY-amide pentapeptide may offer new approaches for cell growth, drug delivery, and 3D bioprinting tissue-engineering applications.

9.
J Chromatogr Sci ; 55(8): 805-812, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472287

RESUMO

Aim of this work was to develop a validated high performance liquid chromatography method for the analysis of extracts and final products of St. John's wort, according to international guidelines for bioanalytical method validation. Chromatographic separation was performed on a C18 column with a combination of gradient and isocratic steps; the mobile phase composed of ammonium acetate solution (pH 4.5; 10 mM), acetonitrile and methanol. Quantification and method validation was performed using extract spiked with external reference standards of chlorogenic acid, rutin, hyperoside, isoquercitrin, quercetin and hypericin. Validation study revealed that trans-chlorogenic acid is partially transformed into its cis-isomer during analysis. The method showed good linearity, precision and accuracy. Hyperforin was completely unstable. All other ingredients were stable at -18°C and after three freeze-thaw cycles, while stability of most ingredients was limited at room temperature and 4 - 8°C; quercetin was the most unstable one. The major ingredients of methanolic extracts, infusions and final products of Hypericum perforatum were completely resolved and quantified. Beyond its potential usefulness in the analysis of St. John's wort products, this study addresses the issue of validation from the perspective of the field of bioanalysis and reveals the wealth of critical information which can be derived.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Hypericum/química , Extratos Vegetais/química , Antracenos , Ácido Clorogênico/análise , Ácido Clorogênico/química , Estabilidade de Medicamentos , Modelos Lineares , Perileno/análogos & derivados , Perileno/análise , Perileno/química , Quercetina/análise , Quercetina/química , Reprodutibilidade dos Testes , Rutina/análise , Rutina/química , Sensibilidade e Especificidade
10.
Biomed Res Int ; 2014: 963230, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25003133

RESUMO

BACKGROUND: N-Glycolylneuraminic acid (Neu5Gc) is a sialic acid synthesized by animals, but not by humans or birds. However, it can be incorporated in human cells and can trigger immune response. In the present study, we detected anti-Neu5Gc antibodies in samples of the general population and of patients suffering from hypothyroidism/Hashimoto's disease, which is known to have autoimmune origin. METHODS: Antibodies were measured using enzyme-immunosorbent techniques. RESULTS: Serum anti-Neu5Gc IgG antibodies were higher in patients with hypothyroidism (mean: 14.8 ± 15.9 µg/mL, median: 10.0 µg/mL, P = 0.0003, Mann-Whitney) and even higher in the group with Hashimoto's thyroiditis (mean: 31.1 ± 16.3 µg/mL, median: 27.2 µg/mL, P = 0.0000, Mann-Whitney) compared to the general population (mean: 5.3 ± 4.7 µg/mL, median : 4 µg/mL). All anti-TPO positive samples had anti-Neu5Gc antibody concentration higher than the mean value of the general population while anti-TPO concentration was increased as anti-Neu5Gc concentration increased. Low concentrations of IgA and IgM antibodies were measured in both general population and patient groups. CONCLUSION: The increased values of anti-Neu5Gc antibodies in patients with hypothyroidism/Hashimoto's disease and the correlation of anti-TPO incidence with increased anti-Neu5Gc concentration raise the possibility of an association between anti-Neu5Gc antibody development and autoimmune hypothyroidism.


Assuntos
Anticorpos/sangue , Hipotireoidismo/sangue , Hipotireoidismo/imunologia , Ácidos Neuramínicos/imunologia , Adulto , Idoso , Artrite Reumatoide/imunologia , Feminino , Doença de Hashimoto/imunologia , Humanos , Iodeto Peroxidase/imunologia , Masculino , Pessoa de Meia-Idade , Tireoglobulina/imunologia
11.
Hell J Nucl Med ; 17 Suppl 1: 35-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24392467

RESUMO

Diabetes Mellitus type I (DM1) and II (DM2) share the common characteristic of high blood glucose concentration and the health complications resulting from uncontrolled hyperglycemia such as hyperlipidemia, cardiovascular problems, stroke, ketoacidosis, kidney failure and blindness but have different etiology. DM1 is practically an autoimmune disease. Genetic susceptibility together with environmental factors leads to disease development. The main characteristics of Diabetes type II (DM2) is insulin resistance in muscle and liver cells accompanied by loss of ß-cell function. However, adipose tissue, gastro-intestinal tract, pancreatic a-cell activity, may be involved in disease development. In parallel to the impairment of endocrine pancreatic function, a reduction in exocrine function has also been observed in all types of Diabetes Mellitus. A decrease in amylase and lipase activity has been mentioned by many authors, although cases with elevated amylase have been referred. Most recently a trend for positive correlation between HDL cholesterol and amylase in Diabetes type II patients was shown. In the present study we evaluated the lipidemic profile and related factors such as cortisol, total serum antioxidant capacity (TAC) and amylase in patients suffering from diabetes type I and II. The relationship between different parameters was examined. Blood serum from 20 DM1 patients and 45 DM2 patients was used. Serum from 50 healthy individuals was used as control. Total cholesterol and triglycerides were measured using an enzymatic colorimetric method. Serum cortisol, auto-antibodies and anti-Neu5Gc antibodies were measured using immunoenzyme assays and TAC measurement was made using the ABTS method. Mean total cholesterol was 245.5mg/dL in Diabetes I patients and was significantly elevated compared to healthy individuals as well as Diabetes II patients (168.71±76.0mg/dL). The observed difference was statistically significant (P=0.0004). On the contrary, triglyceride values were within normal range in both cases (123.7±63.2mg/dL in DM1 and 168.1±76.0mg/dL in DM2 patients). Cortisol levels were elevated in both cases with higher values observed in Diabetes type I (280.5±162.9ng/mL in DM1 and 248.5±100.1ng/mL in DM2), while total antioxidant capacity was significantly reduced compared to healthy individuals, 1.470mM, with lower values observed in Diabetes type I (0.680±0.116mM in DM1 and 0.849±0.126mM in DM2). Amylase determination revealed a mean amylase value, 81.7U/ml, within normal range and a negative correlation between cholesterol levels and amylase (r=-0.770) in DM1 patients. No correlation was observed between the determined values or the presence of autoantibodies and antibodies against Neu5Gc in the samples. In conlusion, the lipidemic profile and overall atherogenic and cardiovascular risk factors were worse in Diabetes I compared to Diabetes II patients. Most interestingly, cholesterol levels exhibited a negative correlation with serum amylase values. Since, amylase is not known to be involved in lipid metabolism, cholesterol levels and serum amylase activity may have a common modulator related to Diabetes development.

12.
Health Syst Transit ; 14(6): 1-128, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23149260

RESUMO

The health system in Cyprus comprises separate public and private systems of similar size. The public system, which is financed by the state budget, is highly centralized and tightly controlled by the Ministry of Health. Entitlement to receive free health services is based on residency and income level. The private system is almost completely separate from the public system and for the most part is unregulated and largely financed out of pocket. In many ways there is an imbalance between the public and private sectors. The public system suffers from long waiting lists for many services, a situation that has been worsened by the recent economic crisis, while the private sector has an overcapacity of expensive medical technology that is underutilized. To try to address these and other inefficiencies, a new national health insurance scheme funded by taxes and social insurance contributions has been designed to offer universal coverage and introduce competition between the public and private sectors through changes in provider payment methods. However, the scheme has not been implemented due to cost concerns. Despite the low share of economic resources dedicated to health care and access issues for some vulnerable population groups, overall Cypriots enjoy good health comparable to other high-income countries.


Assuntos
Atenção à Saúde/organização & administração , Política de Saúde , Chipre/epidemiologia , Organização do Financiamento , Reforma dos Serviços de Saúde , Gastos em Saúde , Recursos em Saúde , Acessibilidade aos Serviços de Saúde , Nível de Saúde , Humanos , Seguro Saúde/organização & administração , Programas Nacionais de Saúde/organização & administração
13.
Vasc Cell ; 4: 4, 2012 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-22423616

RESUMO

BACKGROUND: Pleiotrophin (PTN) is a heparin-binding growth factor with significant role(s) in tumour growth and angiogenesis. Although implication of endogenous PTN has been studied in several in vivo models of tumour angiogenesis, its role in physiological angiogenesis has not been addressed. In the present work, we studied expression and functional significance of endogenous PTN during angiogenesis in the chicken embryo chorioallantoic membrane (CAM). METHODS: Using molecular, cellular and biochemical assays, we studied the expression pattern of PTN in CAM and human endothelial cells and its possible interaction with nucleolin (NCL). CAM cells were transfected with a pCDNA3.1 vector, empty (PC) or containing full length cDNA for PTN in antisense orientation (AS-PTN). Angiogenesis was estimated by measuring total vessel length. In vitro, human endothelial cells migration was studied by using a transwell assay, and down-regulation of NCL was performed by using a proper siRNA. RESULTS: Endogenous PTN mRNA and protein levels, as well as protein levels of its receptor protein tyrosine phosphatase beta/zeta (RPTPß/ζ) were maximal at early stages, when CAM angiogenesis is active. Application of AS-PTN onto CAM at days of active angiogenesis was not toxic to the tissue and led to dose-dependent decreased expression of endogenous PTN, ERK1/2 activity and angiogenesis. Interestingly, endogenous PTN was also immunolocalized at the endothelial cell nucleus, possibly through interaction with NCL, a protein that has a significant role in the nuclear translocation of many proteins. Down-regulation of NCL by siRNA in human endothelial cells significantly decreased nuclear PTN, verifying this hypothesis. Moreover, it led to abolishment of PTN-induced endothelial cell migration, suggesting, for the first time, that PTN-NCL interaction has a functional significance. CONCLUSIONS: Expression of endogenous PTN correlates with and seems to be involved in angiogenesis of the chicken embryo CAM. Our data suggest that NCL may have a role, increasing the number of growth factors whose angiogenic/tumorigenic activities are mediated by NCL.

14.
Steroids ; 76(10-11): 974-85, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21722659

RESUMO

Recent reports have indicated that in cells ectopically expressing only ERα or the full-length hormone-binding isoform of ERß (ERß1), the receptors interact with chromatin with different efficacies and that antibodies capable of probing such interactions by chromatin immunoprecipitation (ChIP) are scarce. We therefore produced nine subtype and isoform-specific antibodies to ERα or ERß and validated their performance in receptor probing in cell lines and tissue biopsies by various immunochemical methods, including ChIP. We also produced clones of HEK-293 cells stably transfected with an estrogen response element (ERE)-dependent luciferase reporter and ERα or ERß1, in order to comparatively study their interaction with reporter ERE. We show that ERα was located in the nucleus and ERß1 in the cytoplasm as well as the nucleus of the stably transfected cells, while both receptors were found predominantly in the nucleus in transiently transfected cells and in all estrogen target tissues examined using the same antibodies. The cells displayed wild-type transcriptional activity and canonical regulation of ERE-dependent luciferase expression by estrogen agonists and antagonists. However, unlike ERα, ERß1 recruitment to the reporter ERE could be probed only by sequential ChIP with antibodies to receptor N- and C-terminus. These data suggest that in HEK-293 cells stably expressing ERα or ERß1, ER subtype-specific constraints apply to ERß1 nuclear entry; and that in cells displaying cytoplasmic as well as nuclear localization of ERß1, sequential ChIP with different antibodies to the receptor is the method of choice for probing its interaction with chromatin.


Assuntos
Anticorpos Monoclonais/imunologia , Núcleo Celular/metabolismo , Cromatina/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Western Blotting , Linhagem Celular Tumoral , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imuno-Histoquímica , Imunoprecipitação , Reação em Cadeia da Polimerase , Ligação Proteica
15.
J Pept Sci ; 14(6): 725-30, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18213737

RESUMO

One of the main objectives of our current work is the development of new somatostatin analogs that would retain the general characteristics of [Tyr(3)]octreotate (Tate) while showing potential for clinical application. In this respect, study of their interaction with the sst(2) is crucial in providing preliminary structure-activity relationships data. In the present work we report on the synthesis and the preliminary biological evaluation of a total of 15 new structurally modified [Tyr(3)]octreotate analogs. The binding affinities were determined during competition binding assays in sst(2)-positive rat acinar pancreatic AR4-2J cell membranes using [(125)I-Tyr(3)]octreotide as the radioligand.


Assuntos
Peptídeos Cíclicos/metabolismo , Somatostatina/metabolismo , Animais , Ligação Competitiva , Linhagem Celular Tumoral , Peptídeos Cíclicos/química , Ratos , Somatostatina/análogos & derivados , Relação Estrutura-Atividade
16.
J Cell Physiol ; 211(1): 197-204, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17226792

RESUMO

cGMP-degrading pathways have received little attention in the context of angiogenesis. In the present study we set out to determine whether cGMP-specific phosphodiesterase 5 (PDE5) inhibition affects new blood vessel growth. Incubation of chicken chorioallantoic membranes (CAMs) in vivo with sildenafil increased vascular length in a dose-dependent manner. Moreover, incubation of cultured endothelial cells (ECs) with the PDE5 inhibitor promoted proliferation, migration, and organization into tube-like structures. The effects of sildenafil on the angiogenesis-related properties of EC could be blocked by pre-treatment with the soluble guanylyl cyclase (sGC) inhibitor ODQ or the protein kinase G (PKG) I inhibitor DT-3. In addition, over-expression of sGC in EC led to an enhanced growth and migratory response to sildenafil. To study the signaling pathways implicated in the sildenafil-stimulated angiogenic responses we determined the phosphorylation status of mitogen-activated protein kinase (MAPK) members. Incubation of cells with sildenafil increased both extracellular signal regulated kinase 1/2 (ERK1/2) and p38 phosphorylation in a time-dependent manner. Inhibition of MEK by PD98059 and p38 with SB203580 blocked sildenafil-induced proliferation and migration, respectively, suggesting that these MAPK members are downstream of PDE5 and mediate the angiogenic effects of sildenafil. PDE5 inhibitors could, thus, be used in disease states where neo-vessel growth is desired.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Piperazinas/farmacologia , Sulfonas/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Galinhas , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/enzimologia , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Modelos Biológicos , Purinas/farmacologia , Citrato de Sildenafila , Solubilidade/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA