Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Cell Rep ; 43(4): 114105, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38619967

RESUMO

Natural killer (NK) cells are primary defenders against cancer precursors, but cancer cells can persist by evading immune surveillance. To investigate the genetic mechanisms underlying this evasion, we perform a genome-wide CRISPR screen using B lymphoblastoid cells. SPPL3, a peptidase that cleaves glycosyltransferases in the Golgi, emerges as a top hit facilitating evasion from NK cytotoxicity. SPPL3-deleted cells accumulate glycosyltransferases and complex N-glycans, disrupting not only binding of ligands to NK receptors but also binding of rituximab, a CD20 antibody approved for treating B cell cancers. Notably, inhibiting N-glycan maturation restores receptor binding and sensitivity to NK cells. A secondary CRISPR screen in SPPL3-deficient cells identifies B3GNT2, a transferase-mediating poly-LacNAc extension, as crucial for resistance. Mass spectrometry confirms enrichment of N-glycans bearing poly-LacNAc upon SPPL3 loss. Collectively, our study shows the essential role of SPPL3 and poly-LacNAc in cancer immune evasion, suggesting a promising target for cancer treatment.


Assuntos
Células Matadoras Naturais , Polissacarídeos , Humanos , Polissacarídeos/metabolismo , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/imunologia , Amino Açúcares/metabolismo , Genômica/métodos , Rituximab/farmacologia , Rituximab/metabolismo , Linhagem Celular Tumoral
2.
Cancer Cell ; 42(2): 238-252.e9, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38215749

RESUMO

Diffuse large B cell lymphoma (DLBCL) is an aggressive, profoundly heterogeneous cancer, presenting a challenge for precision medicine. Bruton's tyrosine kinase (BTK) inhibitors block B cell receptor (BCR) signaling and are particularly effective in certain molecular subtypes of DLBCL that rely on chronic active BCR signaling to promote oncogenic NF-κB. The MCD genetic subtype, which often acquires mutations in the BCR subunit, CD79B, and in the innate immune adapter, MYD88L265P, typically resists chemotherapy but responds exceptionally to BTK inhibitors. However, the underlying mechanisms of response to BTK inhibitors are poorly understood. Herein, we find a non-canonical form of chronic selective autophagy in MCD DLBCL that targets ubiquitinated MYD88L265P for degradation in a TBK1-dependent manner. MCD tumors acquire genetic and epigenetic alterations that attenuate this autophagic tumor suppressive pathway. In contrast, BTK inhibitors promote autophagic degradation of MYD88L265P, thus explaining their exceptional clinical benefit in MCD DLBCL.


Assuntos
Linfoma Difuso de Grandes Células B , Humanos , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/farmacologia , Transdução de Sinais , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Autofagia
3.
J Int Med Res ; 50(4): 3000605221076925, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35422155

RESUMO

OBJECTIVE: The long-term outcomes of primary carotid artery closure after carotid endarterectomy (CEA) have not been sufficiently studied. This prospective study was performed to analyze the 5-year outcomes of the non-shunting and primary arterial repair technique for CEA. METHODS: This study involved 150 patients who underwent CEA with the primary arterial closure technique without arterial shunting and completed 5 years of follow-up. RESULTS: The patients comprised 107 men and 43 women. The 30-day postoperative course was uneventful in 147 (98.0%) patients; however, cerebrovascular accidents occurred in 3 (2.0%) patients. With respect to the long-term results, most cases of restenosis at 5 years were <50%. Two patients developed asymptomatic total internal carotid artery occlusion. Eleven deaths occurred (mortality rate of 7.3%); one death (0.7%) occurred in the first 30 days. CONCLUSION: Primary arteriotomy closure provides very good long-term patency. Routine use of patch closure is unnecessary.


Assuntos
Estenose das Carótidas , Endarterectomia das Carótidas , Acidente Vascular Cerebral , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/efeitos adversos , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Recidiva , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
4.
Eur J Nucl Med Mol Imaging ; 49(6): 1822-1832, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34957527

RESUMO

PURPOSE: The fibroblast activation protein (FAP) is an emerging target for molecular imaging and therapy in cancer. OncoFAP is a novel small organic ligand for FAP with very high affinity. In this translational study, we establish [68Ga]Ga-OncoFAP-DOTAGA (68Ga-OncoFAP) radiolabeling, benchmark its properties in preclinical imaging, and evaluate its application in clinical PET scanning. METHODS: 68Ga-OncoFAP was synthesized in a cassette-based fully automated labeling module. Lipophilicity, affinity, and serum stability of 68Ga-OncoFAP were assessed by determining logD7.4, IC50 values, and radiochemical purity. 68Ga-OncoFAP tumor uptake and imaging properties were assessed in preclinical dynamic PET/MRI in murine subcutaneous tumor models. Finally, biodistribution and uptake in a variety of tumor types were analyzed in 12 patients based on individual clinical indications that received 163 ± 50 MBq 68Ga-OncoFAP combined with PET/CT and PET/MRI. RESULTS: 68Ga-OncoFAP radiosynthesis was accomplished with high radiochemical yields. Affinity for FAP, lipophilicity, and stability of 68Ga-OncoFAP measured are ideally suited for PET imaging. PET and gamma counting-based biodistribution demonstrated beneficial tracer kinetics and high uptake in murine FAP-expressing tumor models with high tumor-to-blood ratios of 8.6 ± 5.1 at 1 h and 38.1 ± 33.1 at 3 h p.i. Clinical 68Ga-OncoFAP-PET/CT and PET/MRI demonstrated favorable biodistribution and kinetics with high and reliable uptake in primary cancers (SUVmax 12.3 ± 2.3), lymph nodes (SUVmax 9.7 ± 8.3), and distant metastases (SUVmax up to 20.0). CONCLUSION: Favorable radiochemical properties, rapid clearance from organs and soft tissues, and intense tumor uptake validate 68Ga-OncoFAP as a powerful alternative to currently available FAP tracers.


Assuntos
Radioisótopos de Gálio , Neoplasias , Animais , Fibroblastos/metabolismo , Humanos , Ligantes , Camundongos , Neoplasias/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos , Distribuição Tecidual
5.
Blood ; 139(4): 538-553, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34624079

RESUMO

Burkitt lymphoma (BL) is an aggressive lymphoma type that is currently treated by intensive chemoimmunotherapy. Despite the favorable clinical outcome for most patients with BL, chemotherapy-related toxicity and disease relapse remain major clinical challenges, emphasizing the need for innovative therapies. Using genome-scale CRISPR-Cas9 screens, we identified B-cell receptor (BCR) signaling, specific transcriptional regulators, and one-carbon metabolism as vulnerabilities in BL. We focused on serine hydroxymethyltransferase 2 (SHMT2), a key enzyme in one-carbon metabolism. Inhibition of SHMT2 by either knockdown or pharmacological compounds induced anti-BL effects in vitro and in vivo. Mechanistically, SHMT2 inhibition led to a significant reduction of intracellular glycine and formate levels, which inhibited the mTOR pathway and thereby triggered autophagic degradation of the oncogenic transcription factor TCF3. Consequently, this led to a collapse of tonic BCR signaling, which is controlled by TCF3 and is essential for BL cell survival. In terms of clinical translation, we also identified drugs such as methotrexate that synergized with SHMT inhibitors. Overall, our study has uncovered the dependency landscape in BL, identified and validated SHMT2 as a drug target, and revealed a mechanistic link between SHMT2 and the transcriptional master regulator TCF3, opening up new perspectives for innovative therapies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/metabolismo , Glicina Hidroximetiltransferase/antagonistas & inibidores , Glicina Hidroximetiltransferase/metabolismo , Animais , Linfoma de Burkitt/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas , Formiatos/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Glicina/metabolismo , Glicina Hidroximetiltransferase/genética , Humanos , Camundongos , Terapia de Alvo Molecular , Proteólise/efeitos dos fármacos
6.
Nat Prod Res ; 35(14): 2420-2423, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31581848

RESUMO

This study made it possible to characterise by GC (in combination with retention indices), GC-MS and 13C NMR, the chemical composition of the essential oils from Solanum rugosum and Solanum erianthum, two Solanaceae of the Ivorian flora. The two essential oils were characterised by a very high proportion of sesquiterpenes. Specifically, the essential oil of S. rugosum was dominated by (E)-ß-caryophyllene (33.7%), ß-elemol (19.8%) and germacrene D (14.4%), while that of S. erianthum was mainly composed of α-humulene (38.6%), ß-elemol (17.8%) and (E)-ß-caryophyllene (16.7%). The chemical composition of Solanum rugosum is described here for the first time.


Assuntos
Óleos Voláteis/química , Folhas de Planta/química , Solanum/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Côte d'Ivoire , Sesquiterpenos/química , Sesquiterpenos de Germacrano/química
7.
J Colloid Interface Sci ; 577: 319-328, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32497917

RESUMO

A fast, simple, instrument-free room temperature synthesis of stable electroactive surfactant-free colloidal Pt nanoparticles in alkaline methanol and methanol-water mixtures is presented. Pair distribution function (PDF) analysis suggests that methoxy substitution of chloride ligands from H2PtCl6 occurs in methanol. X-ray absorption spectroscopy (XAS) studies and UV-vis measurements show that solutions of H2PtCl6 in methanol age and are reduced to Pt(II) species over time. These species are ideal precursors to significantly reduce the induction period typically observed in colloidal Pt nanoparticle syntheses as well as the temperature needed to form nanoparticles. The room temperature synthesis presented here allows designing simple in situ studies of the nanoparticle formation. In situ infra-red spectroscopy gives insight into the formation and stabilization mechanism of surfactant-free nanoparticles by CO surface groups. Finally, the surfactant-free nanoparticles ca. 2-3 nm in diameter obtained are shown to be readily active electrocatalysts e.g. for methanol oxidation. The synthesis approach presented bears several advantages to design new studies and new syntheses of surfactant-free colloidal nanomaterials.

8.
Cancer Cell ; 37(4): 551-568.e14, 2020 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-32289277

RESUMO

The development of precision medicine approaches for diffuse large B cell lymphoma (DLBCL) is confounded by its pronounced genetic, phenotypic, and clinical heterogeneity. Recent multiplatform genomic studies revealed the existence of genetic subtypes of DLBCL using clustering methodologies. Here, we describe an algorithm that determines the probability that a patient's lymphoma belongs to one of seven genetic subtypes based on its genetic features. This classification reveals genetic similarities between these DLBCL subtypes and various indolent and extranodal lymphoma types, suggesting a shared pathogenesis. These genetic subtypes also have distinct gene expression profiles, immune microenvironments, and outcomes following immunochemotherapy. Functional analysis of genetic subtype models highlights distinct vulnerabilities to targeted therapy, supporting the use of this classification in precision medicine trials.


Assuntos
Biomarcadores Tumorais/genética , Heterogeneidade Genética , Linfoma Difuso de Grandes Células B/classificação , Linfoma Difuso de Grandes Células B/genética , Terapia de Alvo Molecular , Animais , Apoptose , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Medicina de Precisão , Células Tumorais Cultivadas , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Pharm Pharmacol ; 71(12): 1800-1808, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31579950

RESUMO

OBJECTIVES: This study was conducted to evaluate the effect of eplerenone on the RAAS and kidney function in rats with thyroid hormone disorders. METHODS: This study involved 30 male Wistar albino rats, divided into three groups. The first group (N = 6) served as a control. The second group involved 12 rats with experimentally induced hypothyroidism through receiving propylthiouracil (0.05% w/v) in drinking water for one month, which was divided into two subgroups of six rats each. The first subgroup served as a positive hypothyroid control, and the second subgroup received oral daily dose of eplerenone (100 mg/kg) for 14 days. The third group included 12 rats with induced hyperthyroidism with L-thyroxin (0.0012% w/v) in drinking water, and rats in this group were also divided into two subgroups. The first subgroup served as a positive hyperthyroid control, and the second subgroup received oral eplerenone 100 mg/kg. RESULTS: Eplerenone indicated a significant increase in renin and angiotensin I from 184.09 pg/ml and 178.66 pg/ml to 603.31 pg/ml and 250.88 pg/ml, respectively, meanwhile, aldosterone indicated no significant changes after inducing hypothyroidism and eplerenone administration. The induction of hyperthyroidism led to a significant increase in angiotensin I from 248.84 pg/ml to 292.22 pg/ml. Oral administration of eplerenone for 14 days caused a significant increase aldosterone from 364.23 pg/ml to 497.02 pg/ml. CONCLUSION: Eplerenone significantly increased the serum renin and angiotensin I in hypothyroid and aldosterone and angiotensin I in hyperthyroid rats. Aldosterone in hypothyroid rats was not changed by eplerenone.


Assuntos
Eplerenona/farmacologia , Hipertireoidismo/fisiopatologia , Hipotireoidismo/fisiopatologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Aldosterona/metabolismo , Angiotensina I/metabolismo , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/farmacologia , Eplerenona/administração & dosagem , Masculino , Ratos , Ratos Wistar , Renina/metabolismo
10.
Toxicol Sci ; 172(2): 330-343, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31550007

RESUMO

Saliva has become a favorable sample matrix for biomonitoring due to its noninvasive attributes and overall flexibility in collection. To ensure measured salivary concentrations reflect the exposure, a solid understanding of the salivary transport mechanism and relationships between salivary concentrations and other monitored matrices (ie, blood, urine) is needed. Salivary transport of a commonly applied herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D), was observed in vitro and in vivo and a physiologically based pharmacokinetic (PBPK) model was developed to translate observations from the cell culture model to those in animal models and further evaluate 2,4-D kinetics in humans. Although apparent differences in experimental in vitro and in vivo saliva:plasma ratios (0.034 and 0.0079) were observed, simulations with the PBPK model demonstrated dynamic time and dose-dependent saliva:plasma ratios, elucidating key mechanisms affecting salivary transport. The model suggested that 2,4-D exhibited diffusion-limited transport to saliva and was additionally impacted by protein binding saturation and permeability across the salivary gland. Consideration of sampling times post-exposure and potential saturation of transport mechanisms are then critical aspects for interpreting salivary 2,4-D biomonitoring observations. This work utilized PBPK modeling in in vitro to in vivo translation to explore benefits and limitations of salivary analysis for occupational biomonitoring.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacocinética , Ácido 2,4-Diclorofenoxiacético/toxicidade , Monitoramento Biológico/métodos , Modelos Biológicos , Saliva/química , Ácido 2,4-Diclorofenoxiacético/sangue , Administração Oral , Animais , Transporte Biológico , Relação Dose-Resposta a Droga , Humanos , Injeções Intravenosas , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/metabolismo , Fatores de Tempo , Toxicocinética
11.
Toxicology ; 410: 171-181, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30118794

RESUMO

The objective of this study was to evaluate the potential for non-invasive biomonitoring of 2,4-Dichlorophenoxyacetic acid (2,4-D) in saliva. Using an in vitro rat salivary gland epithelial cell (SGEC) system, a collection of experiments investigating chemical protein binding, temporal and directional transport, as well as competitive transport with para-aminohippuric acid (PAH), a substrate for renal organic anion transporters, was conducted to identify cellular transport parameters required to computationally model salivary transport of 2,4-D. Additionally, a physiological protein gradient was implemented to mimic physiologically relevant concentrations of protein in rat plasma and saliva, and under these conditions the transfer of 2,4-D was markedly slower, driven by increased protein binding (i.e. reduced free 2,4-D species available to cross salivary barrier). The rate of transfer was directly proportional to the amount of unbound 2,4-D and demonstrated no indication of active transport. An in vivo assessment of 2,4-D exposure in rats revealed non-linear protein binding in plasma, indicating saturated protein binding and increased levels of unbound 2,4-D species at higher doses. A strong correlation between 2,4-D concentrations in saliva and unbound 2,4-D in plasma was observed (Pearson correlation coefficient = 0.95). Saliva:plasma 2,4-D ratios measured in vivo (0.0079) were consistent within the linear protein binding range and expected 2,4-D levels from occupational exposures but were significantly different than ratios measured in vitro (physiological conditions) (0.034), possibly due to 2,4-D concentrations in saliva not being at equilibrium with 2,4-D concentrations in blood, as well as physiological features absent in in vitro settings (e.g. blood flow). We demonstrated that 2,4-D is consistently transported into saliva using both in vitro and in vivo models, making 2,4-D a potential candidate for human non-invasive salivary biomonitoring. Further work is needed to understand whether current sensor limits of detection are sufficient to measure occupationally relevant exposures.


Assuntos
Ácido 2,4-Diclorofenoxiacético/análise , Monitoramento Ambiental/métodos , Herbicidas/análise , Saliva/química , Ácido 2,4-Diclorofenoxiacético/sangue , Ácido 2,4-Diclorofenoxiacético/farmacocinética , Animais , Polaridade Celular/efeitos dos fármacos , Células Epiteliais , Herbicidas/sangue , Herbicidas/farmacocinética , Masculino , Exposição Ocupacional , Cultura Primária de Células , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Glândulas Salivares/citologia , Glândulas Salivares/metabolismo , Junções Íntimas/efeitos dos fármacos
12.
Sci Rep ; 8(1): 4670, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29549309

RESUMO

Small-conductance Ca2+-activated K+ (SK) channels regulate the excitability of cardiomyocytes by integrating intracellular Ca2+ and membrane potentials on a beat-to-beat basis. The inextricable interplay between activation of SK channels and Ca2+ dynamics suggests the pathology of one begets another. Yet, the exact mechanistic underpinning for the activation of cardiac SK channels remains unaddressed. Here, we investigated the intracellular Ca2+ microdomains necessary for SK channel activation. SK currents coupled with Ca2+ influx via L-type Ca2+ channels (LTCCs) continued to be elicited after application of caffeine, ryanodine or thapsigargin to deplete SR Ca2+ store, suggesting that LTCCs provide the immediate Ca2+ microdomain for the activation of SK channels in cardiomyocytes. Super-resolution imaging of SK2, Cav1.2 Ca2+ channel, and ryanodine receptor 2 (RyR2) was performed to quantify the nearest neighbor distances (NND) and localized the three molecules within hundreds of nanometers. The distribution of NND between SK2 and RyR2 as well as SK2 and Cav1.2 was bimodal, suggesting a spatial relationship between the channels. The activation mechanism revealed by our study paved the way for the understanding of the roles of SK channels on the feedback mechanism to regulate the activities of LTCCs and RyR2 to influence local and global Ca2+ signaling.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Miócitos Cardíacos/fisiologia , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Baixa/metabolismo , Animais , Cafeína/farmacologia , Sinalização do Cálcio , Células Cultivadas , Células HEK293 , Humanos , Masculino , Potenciais da Membrana , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Coelhos , Rianodina/farmacologia , Tapsigargina/farmacologia
13.
Rev. bras. farmacogn ; 27(4): 414-418, July-Aug. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-898687

RESUMO

ABSTRACT One oil sample isolated from leaves of Artabotrys jollyanus Pierre, Annonaceae, from Côte d'Ivoire has been analyzed by GC(RI), GC-MS and 13C NMR. In total, thirty-seven compounds accounting for 96.9% of the relative composition have been identified. The composition of the essential oil was dominated by trans-calamenene (15.7%), α-copaene (14.8%), α-cubebene (10.4%), cadina-3,5-diene (10.3%), (E)-β-caryophyllene (6.3%) and cadina-1,4-diene (6.1%). 13C NMR spectroscopy was very useful in the identification of trans-calamenene, 7-hydroxycalamenene, cadina-3,5-diene and cadina-1,4-diene. Moreover, monitoring the evolution of the leaf essential oil composition and the yield on a 12-month period (one sample per month) was achieved. The twelve essential oil samples exhibited a chemical homogeneity but the yield varied from sample to sample (0.26-0.60%).

14.
Toxicol Sci ; 157(2): 438-450, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28402492

RESUMO

A combination experimental and computational approach was developed to predict chemical transport into saliva. A serous-acinar chemical transport assay was established to measure chemical transport with nonphysiological (standard cell culture medium) and physiological (using surrogate plasma and saliva medium) conditions using 3,5,6-trichloro-2-pyridinol (TCPy) a metabolite of the pesticide chlorpyrifos. High levels of TCPy protein binding were observed in cell culture medium and rat plasma resulting in different TCPy transport behaviors in the 2 experimental conditions. In the nonphysiological transport experiment, TCPy reached equilibrium at equivalent concentrations in apical and basolateral chambers. At higher TCPy doses, increased unbound TCPy was observed, and TCPy concentrations in apical and basolateral chambers reached equilibrium faster than lower doses, suggesting only unbound TCPy is able to cross the cellular monolayer. In the physiological experiment, TCPy transport was slower than nonphysiological conditions, and equilibrium was achieved at different concentrations in apical and basolateral chambers at a comparable ratio (0.034) to what was previously measured in rats dosed with TCPy (saliva:blood ratio: 0.049). A cellular transport computational model was developed based on TCPy protein binding kinetics and simulated all transport experiments reasonably well using different permeability coefficients for the 2 experimental conditions (1.14 vs 0.4 cm/h for nonphysiological and physiological experiments, respectively). The computational model was integrated into a physiologically based pharmacokinetic model and accurately predicted TCPy concentrations in saliva of rats dosed with TCPy. Overall, this study demonstrates an approach to predict chemical transport in saliva, potentially increasing the utility of salivary biomonitoring in the future.


Assuntos
Clorpirifos/metabolismo , Inseticidas/metabolismo , Modelos Biológicos , Piridonas/farmacocinética , Saliva/metabolismo , Células Acinares/metabolismo , Animais , Transporte Biológico , Células Cultivadas , Biologia Computacional , Masculino , Valor Preditivo dos Testes , Piridonas/sangue , Ratos Sprague-Dawley
15.
Nat Prod Res ; 31(15): 1836-1839, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28278653

RESUMO

The chemical composition of leaf essential oil from Artabotrys insignis Engler & Diels collected from Cote d'Ivoire was determined by GC(FID), GC-MS and 13C NMR. The main compounds were ß-elemene (66.8%) and germacrene A (17.1%). The true content of germacrene A/ß-elemene was obtained by combining GC(FID) and 13C NMR data.


Assuntos
Annonaceae/química , Óleos Voláteis/química , Sesquiterpenos de Germacrano/análise , Sesquiterpenos/análise , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Côte d'Ivoire , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/análise , Folhas de Planta/química
16.
J Expo Sci Environ Epidemiol ; 27(1): 72-77, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26555474

RESUMO

Direct measurements of exposure represent the most accurate assessment of a subject's true exposure. The clearance of many drugs and chemicals, including pesticides such as chlorpyrifos (CPF), can be detected non-invasively in saliva. Here we have developed a serous-acinar transwell model system as an in vitro screening platform to prioritize chemicals for non-invasive biomonitoring through salivary clearance mechanisms. Rat primary serous-acinar cells express both α-amylase and aquaporin-5 proteins and develop significant tight junctions at postconfluence - a feature necessary for chemical transport studies in vitro. CPF exhibited bidirectional passage across the serous-acinar barrier that was disproportional to the passage of a cell impermeable chemical (lucifer yellow), consistent with a hypothesized passive diffusion process. CPF was metabolized to trichlorpyridinol (TCPy) by serous-acinar cells, and TCPy also displayed bidirectional diffusion in the transwell assay. This model system should prove useful as an in vitro screening platform to support the non-invasive monitoring of toxicons and pharmacons in human saliva and provide guidance for development of advanced in vitro screening platforms utilizing primary human salivary gland epithelial cells.


Assuntos
Clorpirifos/análise , Inseticidas/análise , Saliva/metabolismo , Análise de Variância , Animais , Bioensaio , Biomarcadores/metabolismo , Clorpirifos/metabolismo , Monitoramento Ambiental , Células Epiteliais/metabolismo , Técnicas In Vitro , Inseticidas/metabolismo , Masculino , Modelos Biológicos , Ratos , Ratos Sprague-Dawley
17.
Chem Biodivers ; 14(2)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27664083

RESUMO

The chemical composition of trunk bark oil from Cleistopholis patens (Benth.) Engl. & Diels, growing wild in Côte d'Ivoire, has been investigated by GC (FID) in combination with retention indices, GC/MS and 13 C-NMR. Moreover, one oil sample has been subjected to CC and all the fractions analyzed by GC (RI) and 13 C-NMR. In total, 61 components have been identified, including various sesquiterpene esters scarcely found in essential oils. 13 C-NMR was particularly efficient for the identification of a component not eluted on GC and for the quantification of heat-sensitive compounds. Then, 36 oil samples, isolated from trunk bark harvested in six Ivoirian forests have been analyzed. The content of the main components varied drastically from sample to sample: (E)-ß-caryophyllene (0.4 - 69.1%), ß-pinene (0 - 57%), α-phellandrene (0 - 33.2%), α-pinene (0.1 - 30.6%), ß-elemol (0.1 - 29.9%), germacrene D (0 - 25.4%), juvenile hormone III (0 - 22.9%), germacrene B (0 - 20.6%) and sabinene (tr-20.3%). Statistical analysis, hierarchical clustering and principal components analysis, carried out on the 36 compositions evidenced a fair chemical variability of the stem bark oil of this species. Indeed, three clusters have been distinguished: the composition of group I (ten samples) was dominated by ß-pinene and α-pinene, group II (nine samples) was represented by α-phellandrene and p-cymene and group III (16 samples) by ß-elemol. A sample displayed an atypical composition dominated by (E)-ß-caryophyllene.


Assuntos
Annonaceae/química , Casca de Planta/química , Óleos de Plantas/química , África Ocidental , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Óleos de Plantas/isolamento & purificação , Análise de Componente Principal
18.
Chem Biodivers ; 13(3): 293-298, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26916629

RESUMO

The chemical composition of 45 essential oil samples isolated from the leaves of Polyalthia oliveri harvested in three Ivoirian forests was investigated by GC-FID (retention indices measured on two columns of different polarities), and by (13) C-NMR, following a method developed in our laboratory. In total, 41 components were identified. The content of the main components varied drastically from sample to sample: (E)-ß-caryophyllene (1.2 - 50.8%), α-humulene (0.6 - 47.7%), isoguaiene (0 - 27.9%), alloaromadendrene (0 - 24.7%), germacrene B (0 - 18.3%), δ-cadinene (0.4 - 19.3%), and ß-selinene (0.2 - 18.5%). The analysis of six oil samples selected in function of their chromatographic profiles is reported in detail. The 45 oil compositions were submitted to hierarchical cluster and principal components analysis, which allowed the distinction of three groups within the oil samples. The compositions of the oils from group I (15 samples) and II (12 samples) were dominated by (E)-ß-caryophyllene and α-humulene, respectively. Oil samples of group III (18 samples) needed to be partitioned into four subgroups III.1-III.4 whose compositions were dominated by alloaromadenrene, isoguaiene, germacrene B, and δ-cadinene, respectively.


Assuntos
Folhas de Planta/química , Óleos de Plantas/química , Polyalthia/química , Óleos de Plantas/isolamento & purificação
19.
Nutr Metab Cardiovasc Dis ; 26(3): 223-31, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26803591

RESUMO

AIMS: To evaluate the influence of metabolic syndrome (MetS) as well as inflammatory and renal markers on cardiovascular disease (CVD) incidence. METHODS AND RESULTS: During 2001-2002, 1514 men and 1528 women (>18 y) without any clinical evidence of CVD or any other chronic disease, at baseline, living in greater Athens area, Greece, were enrolled. In 2011-2012, the 10-year follow-up was performed in 2583 participants (15% of the participants were lost to follow-up). Incidence of fatal or non-fatal CVD was defined according to WHO-ICD-10 criteria. MetS was defined using three definitions, provided by the National Cholesterol Education Program Adult Treatment panel III (revised NCEP ATP III), the International Diabetes Federation (IDF) or the Harmonized definition. Furthermore, the contributory predictive role of C-reactive protein (CRP), inteleukin-6, uric acid and estimated glomerular filtration rate in the aforementioned models was evaluated. History of MetS-NCEP was positively associated with CVD, adjusting for potential confounding factors (OR:1.83, 95%CI:1.24-2.72). Not statistically significant associations with CVD incidence were observed when using the IDF or the Harmonized definition. Additionally, none of the added inflammatory and renal function markers mediated the influence of MetS on CVD incidence (all p's from Sobel test >0.40). C-statistic values for the MetS definitions used exceeded 0.789 (CI:0.751-0.827), indicating fair-to-good predictive probability of the models. CONCLUSION: Results of the present work revealed the negative impact of MetS-NCEP, but not of the other MetS definitions, on CVD incidence, a key-point that may help in better understanding the role of IDF and Harmonized MetS definitions on CVD.


Assuntos
Doenças Cardiovasculares/epidemiologia , Síndrome Metabólica/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Pressão Sanguínea , Índice de Massa Corporal , Peso Corporal , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/complicações , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Seguimentos , Taxa de Filtração Glomerular , Grécia/epidemiologia , Humanos , Incidência , Interleucina-6/sangue , Modelos Logísticos , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Triglicerídeos/sangue , Ácido Úrico/sangue , Circunferência da Cintura , Adulto Jovem
20.
Oxf Med Case Reports ; 2016(8): omw056, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29497553

RESUMO

Essential palatal myoclonus is a rare movement disorder consisting of continuous rhythmic jerks of the soft palate; it usually develops secondary to brainstem or cerebellar disease called symptomatic rhythmic palatal myoclonus. Diagnosis is usually clinical, and some patients, however, fail to show evidence of a structural lesion like our patient called essential rhythmic palatal myoclonus. We report a 51-year-old man who has suffered from the condition and showed improvements on treatments.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...