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1.
Virologie (Montrouge) ; 27(3): 35-49, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37476987

RESUMO

Enteroviruses (EVs) include many human pathogens of increasing public health concern. These EVs are often associated with mild clinical manifestations, but they can lead to serious complications such as encephalitis, meningitis, pneumonia, myocarditis or poliomyelitis. Despite significant advances, there is no approved antiviral therapy for the treatment of enterovirus infections. Due to the high genotypic diversity of EVs, molecules targeting highly conserved viral proteins may be considered for developing a pan-EV treatment. In this regard, the ATPase/Helicase 2C, which is a highly conserved non-structural protein among EVs, has essential functions for viral replication and is therefore an attractive antiviral target. Recent functional and structural studies on the 2C protein led to the identification of molecules showing ex vivo anti-EV activity and associated with resistance mutations on the coding sequence of the 2C protein. This review presents the current state of knowledge about the 2C protein from an antiviral target perspective and the mode of action of specific inhibitors for this therapeutic target.


Assuntos
Infecções por Enterovirus , Enterovirus , Humanos , Enterovirus/genética , Enterovirus/metabolismo , Antivirais/farmacologia , Antivirais/uso terapêutico , Infecções por Enterovirus/tratamento farmacológico , Antígenos Virais/metabolismo , Antígenos Virais/farmacologia , Antígenos Virais/uso terapêutico , Replicação Viral
2.
Int J Mol Sci ; 23(2)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35055012

RESUMO

Thanks to the crosstalk between Na+ and Ca2+ channels, Na+ and Ca2+ homeostasis interplay in so-called excitable cells enables the generation of action potential in response to electrical stimulation. Here, we investigated the impact of persistent activation of voltage-gated Na+ (NaV) channels by neurotoxins, such as veratridine (VTD), on intracellular Ca2+ concentration ([Ca2+]i) in a model of excitable cells, the rat pituitary GH3b6 cells, in order to identify the molecular actors involved in Na+-Ca2+ homeostasis crosstalk. By combining RT-qPCR, immunoblotting, immunocytochemistry, and patch-clamp techniques, we showed that GH3b6 cells predominantly express the NaV1.3 channel subtype, which likely endorses their voltage-activated Na+ currents. Notably, these Na+ currents were blocked by ICA-121431 and activated by the ß-scorpion toxin Tf2, two selective NaV1.3 channel ligands. Using Fura-2, we showed that VTD induced a [Ca2+]i increase. This effect was suppressed by the selective NaV channel blocker tetrodotoxin, as well by the selective L-type CaV channel (LTCC) blocker nifedipine. We also evidenced that crobenetine, a NaV channel blocker, abolished VTD-induced [Ca2+]i elevation, while it had no effects on LTCC. Altogether, our findings highlight a crosstalk between NaV and LTCC in GH3b6 cells, providing a new insight into the mode of action of neurotoxins.


Assuntos
Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Canais de Sódio Disparados por Voltagem/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Fenômenos Eletrofisiológicos , Imunofluorescência , Expressão Gênica , Ensaios de Triagem em Larga Escala , Ativação do Canal Iônico/efeitos dos fármacos , Canais de Potássio Ativados por Cálcio de Condutância Alta/genética , Neurotoxinas/farmacologia , Técnicas de Patch-Clamp , Ligação Proteica , Isoformas de Proteínas , Ratos , Canais de Sódio Disparados por Voltagem/genética
3.
Molecules ; 27(5)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35268753

RESUMO

Bee venom (BV) is one of the most remarkable natural products that has been a subject of studies since ancient times. Recent studies have shown that Apis mellifera syriaca venom possesses antibacterial as well as cytotoxic effects on cancer cell lines. The venom contains a variety of bioactive molecules-mainly melittin (MEL) and phospholipase A2 (PLA2), as well as other compounds that are not well characterized. In this work, we continue the biological characterization of A. mellifera syriaca venom by testing its anticoagulant effect on human plasma using the prothrombin time (PT) test, as well as assessing its proteolytic activity. In addition, the cytotoxicity of the crude venom-and of its two main components, MEL and PLA2-was tested on HeLa cancer cell lines for the first time. The results obtained showed the capacity of A. mellifera syriaca venom to increase clotting time, thereby proving its anticoagulant effect. Moreover, the venom did not demonstrate a significant proteolytic activity unless administrated at concentrations ≥ 5 mg/mL. Finally, we showed that crude A. mellifera syriaca venom, along with MEL, exhibit a strong in vitro cytotoxic effect on HeLa cancer cell lines, even at low concentrations. In summary, our findings could serve as a basis for the development of new natural-based drug candidates in the therapeutic field.


Assuntos
Meliteno
4.
Molecules ; 27(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36235154

RESUMO

Colorectal cancer (CRC) is ranked the second most lethal type of tumor globally. Thus, developing novel anti-cancer therapeutics that are less aggressive and more potent is needed. Recently, natural bioactive molecules are gaining interest as complementary and supportive antineoplastic treatments due to their safety, effectiveness, and low cost. Jania rubens (J. rubens) is a red coral seaweed abundant in the Mediterranean and bears a significant pharmacological essence. Despite its therapeutic potential, the natural biomolecules extracted from this alga are poorly identified. In this study, the proximal analysis revealed high levels of total ash content (66%), 11.3% proteins, 14.5% carbohydrates, and only 4.5% lipids. The elemental identification showed magnesium and calcium were high among its macro minerals, (24 ± 0.5 mg/g) and (33 ± 0.5 mg/g), respectively. The Chlorophyll of J. rubens was dominated by other pigments with (0.82 ± 0.02 mg/g). A 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay identified effective antioxidant activity in various J. rubens extracts. More importantly, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) tetrazolium reduction and wound healing assays indicate that organic extracts from J. rubens significantly counteract the proliferation of colon cancer cell lines (HCT-116 and HT-29) and inhibit their migratory and metastatic properties in a dose and time-dependent manner. Overall, this study provides insight into the physicochemical properties of red seaweed, J. rubens, and identifies its significant antioxidant, cytotoxic, and anti-migratory potential on two colorectal cell lines, HCT-116 and HT-29.


Assuntos
Antineoplásicos , Neoplasias do Colo , Óleos Voláteis , Rodófitas , Alga Marinha , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Cálcio , Carboidratos , Clorofila , Neoplasias do Colo/tratamento farmacológico , Humanos , Magnésio , Extratos Vegetais/química , Rodófitas/química , Alga Marinha/química
5.
Molecules ; 27(9)2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35566253

RESUMO

COVID-19 has expanded across the world since its discovery in Wuhan (China) and has had a significant impact on people's lives and health. Long COVID is a term coined by the World Health Organization (WHO) to describe a variety of persistent symptoms after acute SARS-CoV-2 infection. Long COVID has been demonstrated to affect various SARS-CoV-2-infected persons, independently of the acute disease severity. The symptoms of long COVID, like acute COVID-19, consist in the set of damage to various organs and systems such as the respiratory, cardiovascular, neurological, endocrine, urinary, and immune systems. Fatigue, dyspnea, cardiac abnormalities, cognitive and attention impairments, sleep disturbances, post-traumatic stress disorder, muscle pain, concentration problems, and headache were all reported as symptoms of long COVID. At the molecular level, the renin-angiotensin system (RAS) is heavily involved in the pathogenesis of this illness, much as it is in the acute phase of the viral infection. In this review, we summarize the impact of long COVID on several organs and tissues, with a special focus on the significance of the RAS in the disease pathogenesis. Long COVID risk factors and potential therapy approaches are also explored.


Assuntos
COVID-19 , Enzima de Conversão de Angiotensina 2 , COVID-19/complicações , Humanos , Peptidil Dipeptidase A/metabolismo , Sistema Renina-Angiotensina/fisiologia , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
6.
Molecules ; 27(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35408447

RESUMO

The binding of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein to its cellular receptor, the angiotensin-converting enzyme 2 (ACE2), causes its downregulation, which subsequently leads to the dysregulation of the renin-angiotensin system (RAS) in favor of the ACE-angiotensin II (Ang II)-angiotensin II type I receptor (AT1R) axis. AT1R has a major role in RAS by being involved in several physiological events including blood pressure control and electrolyte balance. Following SARS-CoV-2 infection, pathogenic episodes generated by the vasoconstriction, proinflammatory, profibrotic, and prooxidative consequences of the Ang II-AT1R axis activation are accompanied by a hyperinflammatory state (cytokine storm) and an acute respiratory distress syndrome (ARDS). AT1R, a member of the G protein-coupled receptor (GPCR) family, modulates Ang II deleterious effects through the activation of multiple downstream signaling pathways, among which are MAP kinases (ERK 1/2, JNK, p38MAPK), receptor tyrosine kinases (PDGF, EGFR, insulin receptor), and nonreceptor tyrosine kinases (Src, JAK/STAT, focal adhesion kinase (FAK)), and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. COVID-19 is well known for generating respiratory symptoms, but because ACE2 is expressed in various body tissues, several extrapulmonary pathologies are also manifested, including neurologic disorders, vasculature and myocardial complications, kidney injury, gastrointestinal symptoms, hepatic injury, hyperglycemia, and dermatologic complications. Therefore, the development of drugs based on RAS blockers, such as angiotensin II receptor blockers (ARBs), that inhibit the damaging axis of the RAS cascade may become one of the most promising approaches for the treatment of COVID-19 in the near future. We herein review the general features of AT1R, with a special focus on the receptor-mediated activation of the different downstream signaling pathways leading to specific cellular responses. In addition, we provide the latest insights into the roles of AT1R in COVID-19 outcomes in different systems of the human body, as well as the role of ARBs as tentative pharmacological agents to treat COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , Receptor Tipo 1 de Angiotensina , Angiotensina I , Angiotensina II , Antagonistas de Receptores de Angiotensina/farmacologia , Enzima de Conversão de Angiotensina 2 , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Humanos , Receptor Tipo 1 de Angiotensina/metabolismo , SARS-CoV-2
7.
Molecules ; 27(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35807390

RESUMO

Voltage-gated Na+ (NaV) channels are significant therapeutic targets for the treatment of cardiac and neurological disorders, thus promoting the search for novel NaV channel ligands. With the objective of discovering new blockers of NaV channel ligands, we screened an In-House vegetal alkaloid library using fluorescence cell-based assays. We screened 62 isoquinoline alkaloids (IA) for their ability to decrease the FRET signal of voltage sensor probes (VSP), which were induced by the activation of NaV channels with batrachotoxin (BTX) in GH3b6 cells. This led to the selection of five IA: liriodenine, oxostephanine, thalmiculine, protopine, and bebeerine, inhibiting the BTX-induced VSP signal with micromolar IC50. These five alkaloids were then assayed using the Na+ fluorescent probe ANG-2 and the patch-clamp technique. Only oxostephanine and liriodenine were able to inhibit the BTX-induced ANG-2 signal in HEK293-hNaV1.3 cells. Indeed, liriodenine and oxostephanine decreased the effects of BTX on Na+ currents elicited by the hNaV1.3 channel, suggesting that conformation change induced by BTX binding could induce a bias in fluorescent assays. However, among the five IA selected in the VSP assay, only bebeerine exhibited strong inhibitory effects against Na+ currents elicited by the hNav1.2 and hNav1.6 channels, with IC50 values below 10 µM. So far, bebeerine is the first BBIQ to have been reported to block NaV channels, with promising therapeutical applications.


Assuntos
Alcaloides , Corantes Fluorescentes , Alcaloides/farmacologia , Batraquiotoxinas/metabolismo , Batraquiotoxinas/farmacologia , Viés , Células HEK293 , Humanos , Isoquinolinas/farmacologia , Ligantes , Sódio/metabolismo
8.
Mar Drugs ; 19(10)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34677461

RESUMO

Voltage-gated sodium channels (VGSCs) are considered to be one of the most important ion channels given their remarkable physiological role. VGSCs constitute a family of large transmembrane proteins that allow transmission, generation, and propagation of action potentials. This occurs by conducting Na+ ions through the membrane, supporting cell excitability and communication signals in various systems. As a result, a wide range of coordination and physiological functions, from locomotion to cognition, can be accomplished. Drugs that target and alter the molecular mechanism of VGSCs' function have highly contributed to the discovery and perception of the function and the structure of this channel. Among those drugs are various marine toxins produced by harmful microorganisms or venomous animals. These toxins have played a key role in understanding the mode of action of VGSCs and in mapping their various allosteric binding sites. Furthermore, marine toxins appear to be an emerging source of therapeutic tools that can relieve pain or treat VGSC-related human channelopathies. Several studies documented the effect of marine toxins on VGSCs as well as their pharmaceutical applications, but none of them underlined the principal marine toxins and their effect on VGSCs. Therefore, this review aims to highlight the neurotoxins produced by marine animals such as pufferfish, shellfish, sea anemone, and cone snail that are active on VGSCs and discuss their pharmaceutical values.


Assuntos
Produtos Biológicos , Toxinas Marinhas/farmacologia , Canais de Sódio Disparados por Voltagem/efeitos dos fármacos , Analgésicos/uso terapêutico , Animais , Humanos , Toxinas Marinhas/uso terapêutico , Dor/tratamento farmacológico , Anêmonas-do-Mar , Frutos do Mar , Caramujos , Tetraodontiformes
9.
Molecules ; 26(8)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919706

RESUMO

Colon carcinogenesis is ranked second globally among human diseases after cardiovascular failures. Bee venom (BV) has been shown to possess in vitro anticancer effects against several types of cancer cells. The two main biopeptides of Apis mellifera BV, namely, melittin (MEL) and phospholipase A2 (PLA2), are suspected to be the biomolecules responsible for the anticancer activity. The present work aims to evaluate the cytotoxic effect of the A. mellifera venom on human colon carcinoma cells (HCT116), and to assess the synergistic effect of MEL and PLA2 on these cells. After analyzing, through high-pressure liquid chromatography, the proportions of MEL and PLA2 on BV, we have established a cell viability assay to evaluate the effect of BV, MEL, PLA2, and a mixture of MEL and PLA2 on the HCT116 cells. Results obtained showed a strong cytotoxicity effect induced by the A. mellifera venom and to a lower extent MEL or PLA2 alone. Remarkably, when MEL and PLA2 were added together, their cytotoxic effect was greatly improved, suggesting a synergistic activity on HCT116 cells. These findings confirm the cytotoxic effect of the A. mellifera venom and highlight the presence of synergistic potential activities between MEL and PLA2, possibly inducing membrane disruption of HCT116 cancer cells. Altogether, these results could serve as a basis for the development of new anticancer treatments.


Assuntos
Abelhas/química , Neoplasias do Colo/patologia , Meliteno/farmacologia , Fosfolipases A2/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Sinergismo Farmacológico , Células HCT116 , Humanos
10.
Molecules ; 26(8)2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33921462

RESUMO

Cardiovascular diseases (CVDs) are considered as a major cause of death worldwide. Therefore, identifying and developing therapeutic strategies to treat and reduce the prevalence of CVDs is a major medical challenge. Several drugs used for the treatment of CVDs, such as captopril, emerged from natural products, namely snake venoms. These venoms are complex mixtures of bioactive molecules, which, among other physiological networks, target the cardiovascular system, leading to them being considered in the development and design of new drugs. In this review, we describe some snake venom molecules targeting the cardiovascular system such as phospholipase A2 (PLA2), natriuretic peptides (NPs), bradykinin-potentiating peptides (BPPs), cysteine-rich secretory proteins (CRISPs), disintegrins, fibrinolytic enzymes, and three-finger toxins (3FTXs). In addition, their molecular targets, and mechanisms of action-vasorelaxation, inhibition of platelet aggregation, cardioprotective activities-are discussed. The dissection of their biological effects at the molecular scale give insights for the development of future snake venom-derived drugs.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Venenos de Serpentes/química , Venenos de Serpentes/uso terapêutico , Animais , Fármacos Cardiovasculares/farmacologia , Fármacos Cardiovasculares/uso terapêutico , Sistema Cardiovascular/efeitos dos fármacos , Sistema Cardiovascular/patologia , Humanos , Modelos Biológicos , Venenos de Serpentes/farmacologia
11.
Molecules ; 26(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34684895

RESUMO

Five protocols were first compared for the copper-catalyzed C-N bond formation between 7-azaindole and aryl/heteroaryl iodides/bromides. The 1-arylated 7-azaindoles thus obtained were subjected to deprotometalation-iodolysis sequences using lithium 2,2,6,6-tetramethylpiperidide as the base and the corresponding zinc diamide as an in situ trap. The reactivity of the substrate was discussed in light of the calculated atomic charges and the pKa values. The behavior of the 1-arylated 7-azaindoles in direct iodination was then studied, and the results explained by considering the HOMO orbital coefficients and the atomic charges. Finally, some of the iodides generated, generally original, were involved in the N-arylation of indole. While crystallographic data were collected for fifteen of the synthesized compounds, biological properties (antimicrobial, antifungal and antioxidant activity) were evaluated for others.

12.
Molecules ; 26(22)2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34834033

RESUMO

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), was first identified in Eastern Asia (Wuhan, China) in December 2019. The virus then spread to Europe and across all continents where it has led to higher mortality and morbidity, and was declared as a pandemic by the World Health Organization (WHO) in March 2020. Recently, different vaccines have been produced and seem to be more or less effective in protecting from COVID-19. The renin-angiotensin system (RAS), an essential enzymatic cascade involved in maintaining blood pressure and electrolyte balance, is involved in the pathogenicity of COVID-19, since the angiotensin-converting enzyme II (ACE2) acts as the cellular receptor for SARS-CoV-2 in many human tissues and organs. In fact, the viral entrance promotes a downregulation of ACE2 followed by RAS balance dysregulation and an overactivation of the angiotensin II (Ang II)-angiotensin II type I receptor (AT1R) axis, which is characterized by a strong vasoconstriction and the induction of the profibrotic, proapoptotic and proinflammatory signalizations in the lungs and other organs. This mechanism features a massive cytokine storm, hypercoagulation, an acute respiratory distress syndrome (ARDS) and subsequent multiple organ damage. While all individuals are vulnerable to SARS-CoV-2, the disease outcome and severity differ among people and countries and depend on a dual interaction between the virus and the affected host. Many studies have already pointed out the importance of host genetic polymorphisms (especially in the RAS) as well as other related factors such age, gender, lifestyle and habits and underlying pathologies or comorbidities (diabetes and cardiovascular diseases) that could render individuals at higher risk of infection and pathogenicity. In this review, we explore the correlation between all these risk factors as well as how and why they could account for severe post-COVID-19 complications.


Assuntos
COVID-19/virologia , Sistema Renina-Angiotensina/genética , SARS-CoV-2/fisiologia , COVID-19/genética , Hábitos , Humanos , Estilo de Vida , Polimorfismo Genético , Fatores Sexuais
13.
Molecules ; 24(16)2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31430861

RESUMO

Apitherapy is an alternate therapy that relies on the usage of honeybee products, most importantly bee venom for the treatment of many human diseases. The venom can be introduced into the human body by manual injection or by direct bee stings. Bee venom contains several active molecules such as peptides and enzymes that have advantageous potential in treating inflammation and central nervous system diseases, such as Parkinson's disease, Alzheimer's disease, and amyotrophic lateral sclerosis. Moreover, bee venom has shown promising benefits against different types of cancer as well as anti-viral activity, even against the challenging human immunodeficiency virus (HIV). Many studies described biological activities of bee venom components and launched preclinical trials to improve the potential use of apitoxin and its constituents as the next generation of drugs. The aim of this review is to summarize the main compounds of bee venom, their primary biological properties, mechanisms of action, and their therapeutic values in alternative therapy strategies.


Assuntos
Venenos de Abelha/química , Venenos de Abelha/farmacologia , Abelhas/química , Animais , Doenças do Sistema Nervoso Central/tratamento farmacológico , Humanos , Inflamação/tratamento farmacológico
14.
Artigo em Inglês | MEDLINE | ID: mdl-30199354

RESUMO

In order to assess the air quality in some Lebanese regions, a biomonitoring study based on honey as biomonitor candidate was conducted. For this, 18 samples of honey collected from four regions in Lebanon, were analyzed for their contamination by 16 polycyclic aromatic hydrocarbons (PAHs) and 22 polychlorinated biphenyls (PCBs). Samples were first extracted using a multi-residue extraction method based on the quick, easy, cheap, effective, rugged, and safe extraction method (QuEChERS) followed by a concentration step using Solid-phase microextraction (SPME) procedures. The extraction was then followed by chromatographic analysis by gas chromatography-ion-trap tandem mass spectrometry (GC-MS/MS). After PAHs samples assessment, different ratios of founded PAHs were calculated in order to estimate the sources of the pollution by these compounds. The obtained results showed that the four analyzed regions were contaminated with PAHs originated from both pyro and petro genic sources while none of them was found to be contaminated by any of the 22 assessed PCBs. The results of this study show that honey can be used as potential biomonitor candidate allowing the assessment of the pollution statement of a given environment.


Assuntos
Monitoramento Ambiental/métodos , Mel/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluição do Ar/análise , Animais , Abelhas , Cromatografia Gasosa-Espectrometria de Massas/métodos , Líbano , Vigilância de Evento Sentinela , Microextração em Fase Sólida , Espectrometria de Massas em Tandem/métodos
15.
Molecules ; 23(10)2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30360399

RESUMO

Snake venom serves as a tool of defense against threat and helps in prey digestion. It consists of a mixture of enzymes, such as phospholipase A2, metalloproteases, and l-amino acid oxidase, and toxins, including neurotoxins and cytotoxins. Beside their toxicity, venom components possess many pharmacological effects and have been used to design drugs and as biomarkers of diseases. Viperidae is one family of venomous snakes that is found nearly worldwide. However, three main vipers exist in the Middle Eastern region: Montivipera bornmuelleri, Macrovipera lebetina, and Vipera (Daboia) palaestinae. The venoms of these vipers have been the subject of many studies and are considered as a promising source of bioactive molecules. In this review, we present an overview of these three vipers, with a special focus on their venom composition as well as their biological activities, and we discuss further frameworks for the exploration of each venom.


Assuntos
Venenos de Víboras , Viperidae , Animais , Oriente Médio , Venenos de Víboras/química , Venenos de Víboras/uso terapêutico , Viperidae/classificação
17.
Anal Bioanal Chem ; 409(21): 5157-5169, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28681076

RESUMO

An optimized analytical method was developed for the simultaneous analysis of 90 pesticides, 16 polycyclic aromatic hydrocarbons, and 22 polychlorinated biphenyls. The method was based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction using acetonitrile followed by a dispersive solid-phase extraction cleanup using primary-secondary amine and octadecyl (C18). The extract obtained was concentrated by evaporation and then reconstituted with acetonitrile to prepare it for chromatographic analysis by liquid chromatography-triple-quadrupole tandem mass spectrometry and gas chromatography-ion-trap tandem mass spectrometry, which was preceded by a preconcentration step using solid-phase microextraction with appropriate fibers. The combination of the two extraction steps ensured efficient extract cleanup. The use of the two analytical instruments allowed the analysis of a large number of pollutants with a high reliability rate. The method developed was validated for linearity, which was studied with use of matrix-matched calibration curves in the concentration range between 10 and 3000 ng g-1. The correlation coefficient (R 2) obtained was higher than 0.98 for most of the target compounds, with a relative standard deviation lower than 20% for repeatability and reproducibility. The limits of detection and quantification were lower than 20 and 60 ng g-1 respectively for the compounds analyzed, and the recoveries were between 60% and 103% for most compounds. Finally, the method was tested for its efficiency on real samples by the analysis of three honey samples in which seven pesticides and nine polycyclic aromatic hydrocarbons were determined. Graphical Abstract ᅟ.


Assuntos
Mel/análise , Resíduos de Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Microextração em Fase Sólida/métodos , Cromatografia Líquida/métodos , Limite de Detecção , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
18.
Biochem J ; 473(13): 1831-44, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27354560

RESUMO

Calcium plays a key role in cell signalling by its intervention in a wide range of physiological processes. Its entry into cells occurs mainly via voltage-gated calcium channels (VGCC), which are found not only in the plasma membrane of excitable cells but also in cells insensitive to electrical signals. VGCC are composed of different subunits, α1, ß, α2δ and γ, among which the cytosolic ß subunit (Cavß) controls the trafficking of the channel to the plasma membrane, its regulation and its gating properties. For many years, these were the main functions associated with Cavß. However, a growing number of proteins have been found to interact with Cavß, emphasizing the multifunctional role of this versatile protein. Interestingly, some of the newly assigned functions of Cavß are independent of its role in the regulation of VGCC, and thus further increase its functional roles. Based on the identity of Cavß protein partners, this review emphasizes the diverse cellular functions of Cavß and summarizes both past findings as well as recent progress in the understanding of VGCC.


Assuntos
Canais de Cálcio/metabolismo , Animais , Cálcio/metabolismo , Canais de Cálcio/química , Membrana Celular/metabolismo , Humanos , Ligação Proteica , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo
19.
J Environ Sci Health B ; 50(11): 788-96, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26357889

RESUMO

Pesticides are a real concern for the society as their use has become critical, leading sometimes to their accumulation as residues in fruits and vegetables. After examining the pesticides sold in Northern Lebanon, this study is focused on the analysis and identification of pesticides residues in fruits and vegetables that are harvested in this region and treated with the locally sold pesticides. Results show: first, (i) a use of Zineb by the name of another pesticide Micronized Sulfur to avoid prosecution; (ii) a significant presence of Metalaxyl in lemons and oranges; (iii) a significant presence of Trifluralin in strawberries; and (iv) a significant presence of Zineb in lemons and tomatoes. Second, with the use of hemolytic tests on human blood results show: (i) a critical concentration and a significant hemolytic effect of some pesticides used in Lebanon; and (ii) an absence of hemolytic effect in the collected fractions of the different analyzed fruit extracts containing pesticides. Finally, this work is the first step for pesticides' analysis in vegetables and fruits in Lebanon, initiating a wider analytical study in order to control and examine the use of pesticides which, according to our results, could have an adverse effect on human health over a long term.


Assuntos
Contaminação de Alimentos/análise , Frutas/química , Hemolíticos/toxicidade , Resíduos de Praguicidas/análise , Praguicidas/toxicidade , Verduras/química , Células Cultivadas , Citrus , Eritrócitos/efeitos dos fármacos , Análise de Alimentos/métodos , Humanos , Líbano , Praguicidas/análise , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Trifluralina/análise , Zineb/análise
20.
Heliyon ; 10(4): e26154, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38390063

RESUMO

The overlap between mechanical engineering and medicine is expanding more and more over the years. Engineers are now using their expertise to design and create functional biomaterials and are continually collaborating with physicians to improve patient health. In this review, we explore the state of scientific knowledge in the areas of biomaterials, biomechanics, nanomechanics, and computational fluid dynamics (CFD) in relation to the pharmaceutical and medical industry. Focusing on current research and breakthroughs, we provide an overview of how these fields are being used to create new technologies for medical treatments of human patients. Barriers and constraints in these fields, as well as ways to overcome them, are also described in this review. Finally, the potential for future advances in biomaterials to fundamentally change the current approach to medicine and biology is also discussed.

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