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1.
Int J Mol Sci ; 24(7)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37047730

RESUMO

This study aimed to investigate the influence of genetic variants in neuroplasticity-related genes on antidepressant treatment phenotypes. The BDNF-TrkB signaling pathway, as well as the downstream kinases Akt and ERK and the mTOR pathway, have been implicated in depression and neuroplasticity. However, clinicians still struggle with the unpredictability of antidepressant responses in depressed patients. We genotyped 26 polymorphisms in BDNF, NTRK2, NGFR, CREB1, GSK3B, AKT, MAPK1, MTOR, PTEN, ARC, and SYN1 in 80 patients with major depressive disorder treated according to the Texas Medical Algorithm for 27 months at Hospital Magalhães Lemos, Porto, Portugal. Our results showed that BDNF rs6265, PTEN rs12569998, and SYN1 rs1142636 SNP were associated with treatment-resistant depression (TRD). Additionally, MAPK1 rs6928 and GSK3B rs6438552 gene polymorphisms were associated with relapse. Moreover, we found a link between the rs6928 MAPK1 polymorphism and time to relapse. These findings suggest that the BDNF, PTEN, and SYN1 genes may play a role in the development of TRD, while MAPK1 and GSK3B may be associated with relapse. GO analysis revealed enrichment in synaptic and trans-synaptic transmission pathways and glutamate receptor activity with TRD-associated genes. Genetic variants in these genes could potentially be incorporated into predictive models of antidepressant response.


Assuntos
Antidepressivos , Transtorno Depressivo Maior , Humanos , Antidepressivos/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/genética , Proteínas do Tecido Nervoso/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-akt/genética , PTEN Fosfo-Hidrolase/genética , Receptores de Fator de Crescimento Neural/genética , Recidiva , Serina-Treonina Quinases TOR/genética
2.
Crit Rev Food Sci Nutr ; : 1-29, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36037006

RESUMO

The increasing demand for nutraceuticals in the circular economy era has driven the research toward studying bioactive compounds from renewable underexploited resources. In this regard, the exploration of brown algae has shown significant growth and maintains a great promise for the future. One possible explanation could be that brown algae are rich sources of nutritional compounds (polyunsaturated fatty acids, fiber, proteins, minerals, and vitamins) and unique metabolic compounds (phlorotannins, fucoxanthin, fucoidan) with promising biological activities that make them good candidates for nutraceutical applications with increased value-added. In this review, a deep description of bioactive compounds from brown algae is presented. In addition, recent advances in biological activities ascribed to these compounds through in vitro and in vivo assays are pointed out. Delivery strategies to overcome some drawbacks related to the direct application of algae-derived compounds (low solubility, thermal instability, bioavailability, unpleasant organoleptic properties) are also reviewed. Finally, current commercial and legal statuses of ingredients from brown algae are presented, considering future therapeutical and market perspectives as nutraceuticals.

3.
J Fluoresc ; 29(2): 343-346, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30887388

RESUMO

In this work, we report a new chemiluminescence system using bis-(2,4,6-trichlorophenyl) oxalate (TCPO) with hydrogen peroxide and luminol as fluorophore. The intense chemiluminescence reaction here described was fully investigated and it was determined that this fluorescent system has two strong light emissions at 440 and 490 nm, respectively. This new, user friendly, intense and striking light emission chemiluminescence system can be used as a very usefull tool for the design and construction of fluorescencent chemical sensors.

4.
Crit Rev Food Sci Nutr ; 56(14): 2304-19, 2016 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-25779935

RESUMO

Food allergens are a real threat to sensitized individuals. Although food labeling is crucial to provide information to consumers with food allergies, accidental exposure to allergenic proteins may result from undeclared allergenic substances by means of food adulteration, fraud or uncontrolled cross-contamination. Allergens detection in foodstuffs can be a very hard task, due to their presence usually in trace amounts, together with the natural interference of the matrix. Methods for allergens analysis can be mainly divided in two large groups: the immunological assays and the DNA-based ones. Mass spectrometry has also been used as a confirmatory tool. Recently, biosensors appeared as innovative, sensitive, selective, environmentally friendly, cheaper and fast techniques (especially when automated and/or miniaturized), able to effectively replace the classical methodologies. In this review, we present the advances in the field of food allergens detection toward the biosensing strategies and discuss the challenges and future perspectives of this technology.


Assuntos
Alérgenos/química , Técnicas Biossensoriais/métodos , Análise de Alimentos/métodos , Hipersensibilidade Alimentar , Alérgenos/imunologia , Humanos , Sensibilidade e Especificidade
5.
J Environ Sci Health B ; 50(5): 338-45, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25826102

RESUMO

Eruca sativa (rocket salad) has been intensely consumed all over the world, insomuch as, this work was undertaken to evaluate the antioxidant status and the environmental contamination (positive and negative nutritional contribution) of leaves and stems from this vegetable. Antioxidant capacity of rocket salad was assessed by mean of optical methods, such as the total phenolic content (TPC), reducing power assay and DPPH radical scavenging activity. The extent of the environmental contamination was reached through the quantification of thirteen organochlorine pesticides (OCP) by using gas chromatography coupled with electron-capture detector (GC-ECD) and compound confirmations employing gas chromatography tandem mass-spectrometry (GC-MS/MS). The OCP residues were extracted by using Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) methodology.The extent of the environmental contamination was reached through the quantification of thirteen OCP by using gas chromatography coupled with electron-capture detector (GC-ECD) and compound confirmations employing GC-MS/MS. The OCP residues were extracted by using Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) methodology. This demonstrated that leaves presented more antioxidant activity than stems, emphasizing that leaves contained six times more polyphenolic compounds than stems. In what concerns the OCP occurrence, the average recoveries obtained at the three levels tested (40, 60 and 80 µg kg(-1)) ranged from 55% to 149% with a relative standard deviation of 11%, (except hexachrorobenzene). Three vegetables samples were collected from supermarkets and analysed following this study. According to data, only one sample achieved 16.21 of ß-hexachlorocyclohexane, confirmed by GC-MS/MS. About OCP quantification, the data indicated that only one sample achieved 16.21 µg kg(-1) of ß-hexachlorocyclohexane, confirmed by GC-MS/MS, being the QuEChERS a good choice for the of OCPs extraction. Furthermore, the leaves consumption guaranty higher levels of antioxidants than stems.


Assuntos
Antioxidantes/análise , Contaminação de Alimentos/análise , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Verduras/química , Folhas de Planta/química , Caules de Planta/química , Portugal , Medição de Risco
6.
J Biol Chem ; 288(11): 7791-7802, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23344948

RESUMO

It has been known for a long time that mitochondria isolated from hepatocytes treated with glucagon or Ca(2+)-mobilizing agents such as phenylephrine show an increase in their adenine nucleotide (AdN) content, respiratory activity, and calcium retention capacity (CRC). Here, we have studied the role of SCaMC-3/slc25a23, the mitochondrial ATP-Mg/Pi carrier present in adult mouse liver, in the control of mitochondrial AdN levels and respiration in response to Ca(2+) signals as a candidate target of glucagon actions. With the use of SCaMC-3 knock-out (KO) mice, we have found that the carrier is responsible for the accumulation of AdNs in liver mitochondria in a strictly Ca(2+)-dependent way with an S0.5 for Ca(2+) activation of 3.3 ± 0.9 µm. Accumulation of matrix AdNs allows a SCaMC-3-dependent increase in CRC. In addition, SCaMC-3-dependent accumulation of AdNs is required to acquire a fully active state 3 respiration in AdN-depleted liver mitochondria, although further accumulation of AdNs is not followed by increases in respiration. Moreover, glucagon addition to isolated hepatocytes increases oligomycin-sensitive oxygen consumption and maximal respiratory rates in cells derived from wild type, but not SCaMC-3-KO mice and glucagon administration in vivo results in an increase in AdN content, state 3 respiration and CRC in liver mitochondria in wild type but not in SCaMC-3-KO mice. These results show that SCaMC-3 is required for the increase in oxidative phosphorylation observed in liver mitochondria in response to glucagon and Ca(2+)-mobilizing agents, possibly by allowing a Ca(2+)-dependent accumulation of mitochondrial AdNs and matrix Ca(2+), events permissive for other glucagon actions.


Assuntos
Nucleotídeos de Adenina/metabolismo , Antiporters/metabolismo , Cálcio/metabolismo , Regulação da Expressão Gênica , Glucagon/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Oxigênio/metabolismo , Difosfato de Adenosina/química , Trifosfato de Adenosina/química , Animais , Glucose/metabolismo , Cinética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias Hepáticas/metabolismo , Modelos Biológicos , Fosforilação Oxidativa , Consumo de Oxigênio
7.
Pharmaceuticals (Basel) ; 17(3)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38543060

RESUMO

Olive leaves are consumed as an extract or as a whole herbal powder with several potential therapeutic benefits attributed to polyphenols, tocopherol's isomers, and flavonoids, among others. This study assessed the potential variance in the functional features presented by olive leaves from three different Portuguese cultivars-Cobrançosa, Madural, and Verdeal-randomly mix-cultivated in the geographical area of Vale de Salgueiros. Inorganic analysis determined their mineral profiles while an organic analysis measured their total phenolic and flavonoid content, and scanned their phenolic and tocopherol and fatty acid composition. The extracts' biological activity was tested by determining their antimicrobial and antioxidant power as well as their ability to inhibit acetylcholinesterase, butyrylcholinesterase, MAO-A/B, and angiotensin-I-converting enzyme. The inorganic profiles showed them to be an inexpensive source able to address different mineral deficiencies. All cultivars appear to have potential for use as possible antioxidants and future alternative antibiotics against some multidrug-resistant microorganisms, with caution regarding the arsenic content in the Verdeal cultivar. Madural's extract displayed properties to be considered a natural multitarget treatment for Alzheimer's and Parkinson's diseases, depression, and cardiometabolic and dual activity for blood pressure modulation. This work indicates that randomly cultivating different cultivars significantly modifies the leaves' composition while keeping their multifaceted therapeutic value.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38821379

RESUMO

INTRODUCTION: Hemorrhoidal pathology is the most frequent proctological problem with a prevalence of 44% of the adult population. The most effective treatment is surgery but it also has the highest postoperative pain rate with moderate to severe pain rates of 30-40% during the first 24-48 hours. Here lies the importance of seeking measures to improve this situation, such as the pudendal nerve block with local anesthetic. However, the variability of the pudendal nerve sometimes makes its blockade ineffective and for this reason nerve location methods are sought to achieve a higher rate of success. The main aim of the study is to compare pain in the immediate postoperative period (24 h) after hemorrhoidectomy in patients with pudendal nerve block guided by anatomical references and guided by neurostimulation. METHODS: The present project proposes the performance of a single-center, triple-blind, randomized clinical trial of efficacy, carried out under conditions of routine clinical practice. Patients over 18 years old with hemorrhoids refractory to medical treatment, symptomatic grade III-IV and grade II hemorrhoids that do not respond to conservative procedures in a third level hospital in Spain and that are subsidiaries of surgery in major ambulatory surgery will be included. Demographic variables, variables on hemorrhoidal pathology, details of surgery, verbal numeric pain scale in the preoperative period and surgical complications will be collected. RESULTS: Not avaliable until the end of the study. CONCLUSIONS: The pudendal nerve block guided by anatomical landmarks has been shown to be useful in postoperative pain control after hemorrhoidectomy although the use of the neurostimulator has not been well studied and we believe it may improve outcom.

9.
Clin Transl Oncol ; 26(8): 1872-1877, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38506978

RESUMO

PURPOSE: To evaluate feasibility of accelerated partial breast irradiation (APBI) using stereotactic radiotherapy (SBRT) Thirty Gy delivered in 5 fractions for patients with early breast cancer. METHODS: Between January 1st, 2018, and December 31s, 2022, we conducted 117 treatments for patients with early-stage breast cancer. All patients underwent conservative surgery followed by APBI using stereotactic external beam radiotherapy. We analyzed local, regional, distant control, overall survival, toxicity, and cosmetic outcomes. RESULTS: The average age was 62 years. 21.3% ductal and 78.7% invasive carcinomas. Regarding the PTV volume, the median was 198.8 cc (38-794 cc). Treatments were completed in all cases. The median follow-up period was of 21 months (1-62 months). Regarding acute toxicity, no Grade 3-4 toxicities were recorded. One patient experienced Grade 2 neuropathic pain. One patient developed subacute fibrosis and two patients developed telangiectasia as subacute and chronic toxicity. Cosmetic results were "good" or "very good" in 96.3% of cases. None of the patients relapsed at any level (local, regional, or distant) and overall survival during follow.up was 100%. CONCLUSION: APBI with SBRT 30 Gy in 5 fractions in early-stage breast cancer is a feasible technique, very-well tolerated and has excellent oncologic and cosmetic outcome during our follow-up period.


Assuntos
Neoplasias da Mama , Fracionamento da Dose de Radiação , Estudos de Viabilidade , Radiocirurgia , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Pessoa de Meia-Idade , Radiocirurgia/métodos , Radiocirurgia/efeitos adversos , Idoso , Adulto , Carcinoma Ductal de Mama/radioterapia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Ductal de Mama/mortalidade , Idoso de 80 Anos ou mais , Seguimentos , Estudos Retrospectivos , Mastectomia Segmentar
10.
Biochim Biophys Acta ; 1817(10): 1768-75, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22386881

RESUMO

While metformin has been widely used to treat type 2 diabetes for the last fifty years, its mode of action remains unclear. Hence, we investigated the short-term alterations in energy metabolism caused by metformin administration in 3T3-L1 adipocytes. We found that metformin inhibited mitochondrial respiration, although ATP levels remained constant as the decrease in mitochondrial production was compensated by an increase in glycolysis. While AMP/ATP ratios were unaffected by metformin, phosphorylation of AMPK and its downstream target acetyl-CoA carboxylase augmented. The inhibition of respiration provoked a rapid and sustained increase in superoxide levels, despite the increase in UCP2 and superoxide dismutase activity. The inhibition of respiration was rapidly reversed by fatty acids and thus respiration was lower in treated cells in the presence of pyruvate and glucose while rates were identical to control cells when palmitate was the substrate. We conclude that metformin reversibly inhibits mitochondrial respiration, it rapidly activates AMPK without altering the energy charge, and it inhibits fatty acid synthesis. Mitochondrial ß-oxidation is facilitated by reversing the inhibition of complex I and, presumably, by releasing the inhibition of carnitine palmitoyltransferase. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012).


Assuntos
Adipócitos/metabolismo , Ácidos Graxos/farmacologia , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Células 3T3-L1 , Acetil-CoA Carboxilase/metabolismo , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Adipócitos/citologia , Animais , Carnitina O-Palmitoiltransferase/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Ácidos Graxos/metabolismo , Glicólise/efeitos dos fármacos , Camundongos , Oxirredução/efeitos dos fármacos
11.
Anal Bioanal Chem ; 405(12): 3953-63, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23314486

RESUMO

A method using microextraction by packed sorbent (MEPS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) is described for the determination of seven antipsychotic drugs in human plasma. The studied compounds were chlorpromazine (CPZ), haloperidol (HAL), cyamemazine, quetiapine, clozapine, olanzapine (OLZ), and levomepromazine; promazine, protriptyline, and deuterated CPZ were used as internal standards. The validation parameters included selectivity, linearity and limits of detection and quantitation, intra- and interday precision and trueness, recovery, and stability and were studied according to internationally accepted guidelines. The method was found to be linear between the lower limit of quantitation and 1000 ng/mL, except for OLZ and HAL (200 ng/mL), with determination coefficients higher than 0.99 for all analytes, and extraction efficiencies ranged from 62 to 92 %. Intra- and interday precision ranged from 0.24 to 10.67 %, while trueness was within a ±15 % interval from the nominal concentration for all analytes at all studied levels. MEPS has shown to be a rapid procedure for the determination of the selected antipsychotic drugs in human plasma, allowing reducing the handling time and the costs of analysis. Furthermore, GC-MS/MS has demonstrated to be a powerful tool for the simultaneous quantitation of the studied compounds, enabling obtaining adequate selectivity and sensitivity using a sample volume of as low as 0.25 mL.


Assuntos
Antipsicóticos/sangue , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Antipsicóticos/isolamento & purificação , Humanos , Limite de Detecção , Espectrometria de Massas em Tandem/métodos
12.
Antioxidants (Basel) ; 12(8)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37627598

RESUMO

The brain's sensitivity to oxidative stress and neuronal cell death requires effective pharmacotherapy approaches. Current pharmacological therapies are frequently ineffective and display negative side effects. Bioactive chemicals found in plants may provide a potential alternative due to their antioxidant and neuroprotective properties and can be used in therapy and the management of a variety of neuropsychiatric, neurodevelopmental, and neurodegenerative illnesses. Several natural products, including vitamin C, Cammelia sinensis polyphenols, Hypericum perforatum, and Crocus sativus have shown promise in lowering oxidative stress and treating symptoms of major depressive disorder (MDD). Similarly, bioactive compounds such as curcumin, luteolin, resveratrol, quercetin, and plants like Acorus gramineus, Rhodiola rosea, and Ginkgo biloba are associated with neuroprotective effects and symptom improvement in neurodevelopmental disorders such as autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD). Furthermore, in neurodegenerative diseases, natural compounds from Rhodiola rosea, Morinda lucida, and Glutinous rehmannia provide neurological improvement. Further study in clinical samples is required to thoroughly investigate the therapeutic advantages of these bioactive substances for persons suffering from these illnesses.

13.
Antioxidants (Basel) ; 12(2)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36829994

RESUMO

The production and consumption of shrimp species create massive amounts of shrimp bio-waste. In this study, shrimp shell waste from Palaemon serratus and Palaemon varians from the Portuguese coast was characterized. Regarding the antioxidant capacity, the obtained values were between 4.7 and 10.4 mg gallic acid equivalents (GAE)/g dry weight (dw) for Total phenolic content (TPC); 3 and 7 mg ascorbic acid equivalents (AAE)/g dw for Ferric reducing antioxidant power assay (FRAP); 0.4 and 1.2 mg Trolox equivalent (TE)/g dw for 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical scavenging (DPPH•); 4 and 11 mg TE/g dw for 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity (ABTS•+); and 72 and 130 mg TE/g dw for Oxygen radical absorbance capacity (ORAC). For the antimicrobial activity, shrimp shell waste from P. varians formed inhibition zones between 14 and 23 mm. Total carotenoid content values were in the range of 28 and 134 µg/g dw, and according to their HPLC-PAD profile, ß-carotene and astaxanthin contents were between 0.3 and 7.6 µg/g dw and 1.1 and 26.1 µg/g dw, respectively. These studies are critical to recognizing the potential added value of shrimp shell waste as possible colorants and preservatives with antioxidant protection capacity to be used in the food industry.

14.
J Anal Toxicol ; 47(3): 227-235, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36124733

RESUMO

The use of new psychoactive substances has been increasing and constitutes a social and public health problem, and hence, toxicological analysis has become of utmost importance for the detection of such substances. In this article, we present the development and full validation of a simple, user and environmentally friendly, cheap and suitable method for the determination of ketamine and its main metabolite norketamine in hair samples. The procedure included using a miniaturized procedure-microextraction by packed sorbent with mixed-mode sorbent-for sample clean-up. Organic solvents use was minimal, and it was possible to obtain a linear method (0.05-10 ng/mg for both analytes). The extraction efficiency ranged from 32 to 61%, which did not impair sensitivity. The method proved to be selective, precise, accurate and suitable for routine analysis for the determination of said compounds in 50-mg hair samples.


Assuntos
Ketamina , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Reprodutibilidade dos Testes , Cabelo/química , Microextração em Fase Sólida/métodos
15.
Sci Rep ; 13(1): 14250, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37653106

RESUMO

The occurrence of Baltic amber through Europe has traditionally been associated to the spread of the Bell Beaker culture during the 3rd millennium BC. In Iberia, this phenomenon is particularly noticeable in the southern half. Here we present an amber bead recovered in a Late Neolithic funerary cave (3634-3363 cal BC) from northeastern Iberia where more than 12 individuals had been buried. Fourier transform infrared spectroscopy results of four samples revealed their complete resemblance with Baltic succinite reference spectra. Despite being a single bead, this finding provides the earliest evidence for the arrival of Baltic amber to the Mediterranean and Western Europe, before the Bell Beaker phenomenon and more than a millennium earlier than traditionally thought. This finding has implications for our understanding of early exchange networks of exotic materials, and their associated social structures.


Assuntos
Âmbar , Cavernas , Humanos , Europa (Continente) , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Talanta ; 264: 124692, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37276677

RESUMO

Cardiovascular diseases are among the major causes of mortality and morbidity. Warfarin is often prescribed for these disorders, an anticoagulant with inter and intra-dosage variability dose required to achieve the target international normalized ratio. Warfarin presents a narrow therapeutic index, and due to its variability, it can often be associated with the risk of hemorrhage, or in other patients, thromboembolism. Single-nucleotide polymorphisms are included in the causes that contribute to this variability. The Cytochrome P450 (CYP) 2C9*3 genetic polymorphism modifies its enzymatic activity, and hence warfarin's plasmatic concentration. Thus, the need for a selective, rapid, low-cost, and real-time detection device is crucial before prescribing warfarin. In this work, a disposable electrochemical DNA-based biosensor capable of detecting CYP2C9*3 polymorphism was developed. By analyzing genomic databases, two specific 78 base pairs DNA probes; one with the wild-type adenine (Target-A) and another with the cytosine (Target-C) single-nucleotide genetic variation were designed. The biosensor implied the immobilization on screen-printed gold electrodes of a self-assembled monolayer composed by mercaptohexanol and a linear CYP2C9*3 DNA-capture probe. To improve the selectivity and avoid secondary structures a sandwich format of the CYP2C9*3 allele was designed using complementary fluorescein isothiocyanate-labeled signaling DNA probe and enzymatic amplification of the electrochemical signal. Chronoamperometric measurements were performed at a range of 0.015-1.00 nM for both DNA targets achieving limit of detection of 42 p.m. The developed DNA-based biosensor was able to discriminate between the two synthetic target DNA targets, as well as the targeted denatured genomic DNA, extracted from volunteers genotyped as non-variant homozygous (A/A) and heterozygous (A/C) of the CYP2C9*3 polymorphism.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Técnicas Biossensoriais , Humanos , Varfarina , Polimorfismo de Nucleotídeo Único , Farmacogenética , Citocromo P-450 CYP2C9/genética , Hidrocarboneto de Aril Hidroxilases/genética , Vitamina K Epóxido Redutases/genética , Anticoagulantes , DNA/genética , Genótipo , Sondas de DNA/genética
17.
Amino Acids ; 42(5): 1903-11, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21614558

RESUMO

Hyperhomocysteinemia (HHcy) is a risk factor for vascular disease, but the underlying mechanisms remain incompletely defined. Reduced bioavailability of nitric oxide (NO) is a principal manifestation of underlying endothelial dysfunction, which is an initial event in vascular disease. Inhibition of cellular methylation reactions by S-adenosylhomocysteine (AdoHcy), which accumulates during HHcy, has been suggested to contribute to vascular dysfunction. However, thus far, the effect of intracellular AdoHcy accumulation on NO bioavailability has not yet been fully substantiated by experimental evidence. The present study was carried out to evaluate whether disturbances in cellular methylation status affect NO production by cultured human endothelial cells. Here, we show that a hypomethylating environment, induced by the accumulation of AdoHcy, impairs NO production. Consistent with this finding, we observed decreased eNOS expression and activity, but, by contrast, enhanced NOS3 transcription. Taken together, our data support the existence of regulatory post-transcriptional mechanisms modulated by cellular methylation potential leading to impaired NO production by cultured human endothelial cells. As such, our conclusions may have implications for the HHcy-mediated reductions in NO bioavailability and endothelial dysfunction.


Assuntos
Arginina/análogos & derivados , Células Endoteliais/metabolismo , Metilação , Óxido Nítrico/metabolismo , S-Adenosil-Homocisteína/metabolismo , Arginina/metabolismo , Células Cultivadas , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Hiper-Homocisteinemia/metabolismo , Óxido Nítrico/deficiência , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/metabolismo , Doenças Vasculares/metabolismo
18.
J Chem Phys ; 136(17): 174502, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22583244

RESUMO

The solid-fluid coexistence properties of the n - 6 Lennard-Jones system, n from 7 to 12, are reported. The procedure relies on determining Helmholtz free energy curves as a function of volume for each phase independently, from several NVT simulations, and then connecting it to points of known absolute free energy. For n = 12 this requires connecting the simulated points to states of very low densities on the liquid phase, and to a harmonic crystal for the solid phase, which involves many extra simulations for each temperature. For the reference points of the remaining systems, however, the free energy at a given density and temperature can be calculated relative to the n = 12 system. The method presented here involves a generalization of the multiple histogram method to combine simulations performed with different potentials, provided they visit overlapping regions of the phase space, and allows for a precise calculation of relative free energies. The densities, free energies, average potential energies, pressure, and chemical potential at coexistence are presented for up to T∗ = 5.0 and new estimations of the triple points are given for the n - 6 Lennard-Jones system.

19.
J Ethnopharmacol ; 290: 115107, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35176467

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Alzheimer's disease is the most common form of dementia, but its treatment options remain few and ineffective. To find new therapeutic strategies, natural products have gained interest due to their neuroprotective potential, being able to target different pathological hallmarks associated with this disorder. Several plant species are traditionally used due to their empirical neuroprotective effects and it is worth to explore their mechanism of action. AIM OF THE STUDY: This study intended to explore the neuroprotective potential of seven traditional medicinal plants, namely Scutellaria baicalensis, Ginkgo biloba, Hypericum perforatum, Curcuma longa, Lavandula angustifolia, Trigonella foenum-graecum and Rosmarinus officinalis. The safety assessment with reference to pesticides residues was also aimed. MATERIALS AND METHODS: Decoctions prepared from these species were chemically characterized by HPLC-DAD and screened for their ability to scavenge four different free radicals (DPPH•, ABTS•+, O2•‒ and •NO) and to inhibit enzymes related to neurodegeneration (cholinesterases and glycogen synthase kinase-3ß). Cell viability through MTT assay was also evaluated in two different brain cell lines, namely non-tumorigenic D3 human brain endothelial cells (hCMEC/D3) and NSC-34 motor neurons. Furthermore, and using GC, 21 pesticides residues were screened. RESULTS: Regarding chemical composition, chromatographic analysis revealed the presence of several flavonoids, phenolic acids, curcuminoids, phenolic diterpenoids, one alkaloid and one naphthodianthrone in the seven decoctions. All extracts were able to scavenge free radicals and were moderate glycogen synthase kinase-3ß inhibitors; however, they displayed weak to moderate acetylcholinesterase and butyrylcholinesterase inhibition. G. biloba and L. angustifolia decoctions were the less cytotoxic to hCMEC/D3 and NSC-34 cell lines. No pesticides residues were detected. CONCLUSIONS: The results extend the knowledge on the potential use of plant extracts to combat multifactorial disorders, giving new insights into therapeutic avenues for Alzheimer's disease.


Assuntos
Doença de Alzheimer/patologia , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colinesterases/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sequestradores de Radicais Livres/metabolismo , Glicogênio Sintase/efeitos dos fármacos , Humanos , Medicina Tradicional Chinesa/métodos , Fármacos Neuroprotetores/efeitos adversos , Resíduos de Praguicidas/análise , Extratos Vegetais/efeitos adversos
20.
Biochim Biophys Acta ; 1797(6-7): 800-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20388489

RESUMO

Diseases like obesity, diabetes or generalized lipodystrophy cause a chronic elevation of circulating fatty acids that can become cytotoxic, a condition known as lipotoxicity. Fatty acids cause oxidative stress and alterations in mitochondrial structure and function. The uncoupling of the oxidative phosphorylation is one of the most recognized deleterious fatty acid effects and several metabolite transporters are known to mediate in their action. The fatty acid interaction with the carriers leads to membrane depolarization and/or the conversion of the carrier into a pore. The result is the opening of the permeability transition pore and the initiation of apoptosis. Unlike the other members of the mitochondrial carrier superfamily, the eutherian uncoupling protein UCP1 has evolved to achieve its heat-generating capacity in the physiological context provided by the brown adipocyte and therefore it is activated by the low fatty acid concentrations generated by the noradrenaline-stimulated lipolysis.


Assuntos
Ácidos Graxos/metabolismo , Ácidos Graxos/toxicidade , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Humanos , Canais Iônicos/genética , Canais Iônicos/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Modelos Biológicos , Fosforilação Oxidativa , Estresse Oxidativo/efeitos dos fármacos , Filogenia , Desacopladores/metabolismo , Desacopladores/toxicidade , Proteína Desacopladora 1
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