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1.
Sensors (Basel) ; 22(18)2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-36146377

RESUMEN

For decades, near-infrared (NIR) spectroscopy has been a valuable tool for material analysis in a variety of applications, ranging from industrial process monitoring to quality assessment. Traditional spectrometers are typically bulky, fragile and expensive, which makes them unsuitable for portable and in-field use. Thus, there is a growing interest for miniaturized, robust and low-cost NIR sensors. In this study, we demonstrate a handheld NIR spectral sensor module, based on a fully-integrated multipixel detector array, sensitive in the 850-1700 nm wavelength range. Differently from a spectrometer, the spectral sensor measures a limited number of NIR spectral bands. The capabilities of the spectral sensor module were evaluated alongside a commercially available portable spectrometer for two application cases: to quantify the moisture content in rice grains and to classify plastic types. Both devices achieved the two sensing tasks with comparable performance. Moisture quantification was achieved with a root mean square error (RMSE) prediction of 1.4% and 1.1% by the spectral sensor and spectrometer, respectively. Classification of the plastic type was achieved with a prediction accuracy on unknown samples of 100% and 96.4% by the spectral sensor and spectrometer, respectively. The results from this study are promising and demonstrate the potential for the compact NIR modules to be used in a variety of NIR sensing applications.


Asunto(s)
Plásticos , Espectroscopía Infrarroja Corta , Espectroscopía Infrarroja Corta/métodos
2.
Talanta ; 245: 123441, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35405444

RESUMEN

Illicit-drug production, trafficking and seizures are on an all-time high. This consequently raises pressure on investigative authorities to provide rapid forensic results to assist law enforcement and legal processes in drug-related cases. Ideally, every police officer is equipped with a detector to reliably perform drug testing directly at the incident scene. Such a detector should preferably be small, portable, inexpensive and shock-resistant but should also provide sufficient selectivity to prevent erroneous identifications. This study explores the concept of on-site drugs-of-abuse detection using a 1.8 × 2.2 mm2 multipixel near-infrared (NIR) spectral sensor that potentially can be integrated into a smartphone. This integrated sensor, based on an InGaAs-on-silicon technology, exploits an array of resonant-cavity enhanced photodetectors without any moving parts. A 100% correct classification of 11 common illicit drugs, pharmaceuticals and adulterants was achieved by chemometric modelling of the response of 15 wavelength-specific pixels. The performance on actual forensic casework was investigated on 246 cocaine-suspected powders and 39 MDMA-suspected ecstasy tablets yielding an over 90% correct classification in both cases. These findings show that presumptive drug testing by miniaturized spectral sensors is a promising development ultimately paving the way for a fully integrated drug-sensor in mobile communication devices used by law enforcement.


Asunto(s)
Cocaína , Drogas Ilícitas , N-Metil-3,4-metilenodioxianfetamina , Teléfono Inteligente , Detección de Abuso de Sustancias
3.
J Ethnopharmacol ; 113(2): 210-7, 2007 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-17616290

RESUMEN

Salvia miltiorrhiza Bunge (Tanshen), a traditional Chinese herbal medicine, is popularly used to treat cardiovascular disorders. In the present study, effects of tanshinlactone A (C(16)H(12)O(4); M.W. 268), newly discovered from Salvia miltiorrhiza, on phytohemagglutinin (PHA)-stimulated cell proliferation were investigated in human peripheral blood mononuclear cells (PBMC). The results indicated that tanshinlactone A inhibited PBMC proliferation activated with PHA with an IC(50) of 15.6+/-1.9 microM. Cell viability test indicated that inhibitory effects of tanshinlactone A on PBMC proliferation were not through direct cytotoxicity. Furthermore, tanshinlactone A significantly decreased the interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) gene expression in PHA-activated PBMC. It reduced the phosphorylation of mitogen-activated protein kinases (MAPK) involving extracellular signal-regulated protein kinase (ERK), P38, and c-Jun NH(2)-terminal kinase (JNK) in PHA-treated PBMC. We suggested that the inhibitory effects of tanshinlactone A on PHA-induced PBMC proliferation, appeared to be mediated, at least in part, through reduction of MAPK activation and IL-2 and IFN-gamma production. Therefore, data demonstrate for the first time that tanshinlactone A is likely an immunomodulatory agent for PBMC.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Expresión Génica/efectos de los fármacos , Interferón gamma/genética , Interleucina-2/genética , Salvia miltiorrhiza/química , Acetatos/química , Adulto , Western Blotting , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Diterpenos/aislamiento & purificación , Diterpenos/farmacología , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Hexanos/química , Humanos , Interferón gamma/metabolismo , Interleucina-2/metabolismo , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Masculino , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Fenantrenos/aislamiento & purificación , Fenantrenos/farmacología , Fitohemaglutininas/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Raíces de Plantas/química , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
4.
Br J Pharmacol ; 151(5): 638-46, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17471173

RESUMEN

BACKGROUND AND PURPOSE: Cryptotanshinone, the major tanshinone isolated from Salvia miltiorrhiza Bunge, exhibits anti-inflammatory activity. However, there is no report on the effect of cryptotanshinone on recruitment of leukocytes to inflammatory sites. We therefore assessed the effects of cryptotanshinone on macrophage chemotaxis. EXPERIMENTAL APPROACH: Macrophage migration induced by complement 5a (C5a) or macrophage inflammatory protein-1alpha (MIP-1alpha) was measured in vitro. Intracellular kinase translocation and phosphorylation was assessed by Western blotting. KEY RESULTS: RAW264.7 cell migration towards C5a (1 microg ml(-1)) was significantly inhibited by cryptotanshinone (1, 3, 10 and 30 microM) in a concentration-dependent manner. Primary human macrophages stimulated by C5a were similarly inhibited. C5a-evoked migration in RAW264.7 cells was significantly suppressed by wortmannin (phosphatidylinositol 3-kinase (PI3K) inhibitor), PD98059 (MEK1/2 inhibitor) and SB203580 (p38 mitogen-activated protein kinase (MAPK) inhibitor), but not by SP600125 (c-Jun N-terminal kinase (JNK) inhibitor), suggesting that activation of PI3K, ERK1/2 and p38 MAPK signal pathways was involved in responses to C5a. Western blotting revealed that cryptotanshinone significantly inhibited PI3K-p110gamma membrane translocation and phosphorylation of Akt (PI3K downstream effector protein) and ERK1/2 induced by C5a. However, neither p38 MAPK nor JNK phosphorylation was affected by cryptotanshinone. Wortmannin significantly attenuated C5a-induced PI3K-p110gamma translocation, Akt and ERK1/2 phosphorylation. PD98059 suppressed ERK1/2 phosphorylation but failed to modify PI3K-p110gamma translocation by C5a stimulation. Furthermore, MIP-1alpha-induced cell migration and PI3K-p110gamma translocation were also inhibited by cryptotanshinone in a concentration-dependent manner. CONCLUSIONS AND IMPLICATIONS: Inhibition of macrophage migration by cryptotanshinone involved inhibition of PI3K activation with consequent reduction of phosphorylation of Akt and ERK1/2.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Quimiotaxis de Leucocito/efectos de los fármacos , Macrófagos/efectos de los fármacos , Fenantrenos/farmacología , Fosfatidilinositol 3-Quinasas/fisiología , Transducción de Señal/efectos de los fármacos , Androstadienos/farmacología , Western Blotting , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Quimiocina CCL3 , Quimiocina CCL4 , Complemento C5a/fisiología , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Humanos , Técnicas In Vitro , Proteínas Inflamatorias de Macrófagos/farmacología , Proteínas Quinasas Activadas por Mitógenos/fisiología , Fenantrenos/aislamiento & purificación , Fosforilación , Proteínas Quinasas/metabolismo , Transporte de Proteínas/efectos de los fármacos , Salvia/química , Wortmanina
5.
J Nat Prod ; 64(9): 1232-3, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11575964

RESUMEN

Solavetivone (1), cytotoxic to OVCAR-3 cells with an IC(50) value of 0.1 mM, has been isolated from Solanum indicum. In addition, a novel solafuranone (2) and three known compounds, scopoletin, N-(p-trans-coumaroyl)tyramine, and N-trans-feruloyltyramine, were isolated for the first time from this plant. The structures of the above compounds were established by means of spectroscopic and X-ray analyses.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Furanos/aislamiento & purificación , Solanaceae/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Cromatografía , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Furanos/química , Humanos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Medicina Tradicional China , Conformación Molecular , Estructura Molecular , Neoplasias Ováricas , Raíces de Plantas/química , Plantas Medicinales/química , Espectrofotometría Infrarroja , Espectroscopía Infrarroja por Transformada de Fourier , Estereoisomerismo , Relación Estructura-Actividad , Células Tumorales Cultivadas/efectos de los fármacos
6.
Mol Pharmacol ; 59(4): 784-94, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11259623

RESUMEN

beta-Lapachone, a novel anti-neoplastic drug, induces various cancer cells to undergo apoptosis. In a previous report, we showed that beta-lapachone-induced apoptosis of HL-60 cells is mediated by oxidative stress. However, in the present study, we found that beta-lapachone-induced apoptosis of human prostate cancer (HPC) cells may be independent of oxidative stress. In contrast to the 10-fold beta-lapachone-induced increase in H(2)O(2) production seen in HL-60 cells, only a 2- to 4-fold increase was observed in HPC cells. N-acetyl-L-cysteine (NAC), a thiol antioxidant, inhibited the apoptosis in DU145 cells after 12 h exposure to beta-lapachone. Nonetheless, NAC, along with other antioxidants, failed to exert similar effect in HPC cells subjected to beta-lapachone treatment for 24 h. Under this premise, we suggest that the oxidative stress may not play a crucial role in beta-lapachone-mediated HPC cell apoptosis. Here we demonstrate that damage to genomic DNA is the trigger for the apoptosis of HPC cells induced by beta-lapachone. According to our results, beta-lapachone stimulates DNA dependent kinase expression and poly(ADP-ribose) polymerase cleavage in advance of significant morphological changes. beta-Lapachone promotes the expression of cyclin-dependent kinase (cdk) inhibitors (p21(WAF1) and p27(Kip1)), induces bak expression, and subsequently stimulates the activation of caspase-7 but not of caspase-3 or caspase-8 during the apoptosis of HPC cells. Taken together, these results suggest that the signaling pathway involving the beta-lapachone-induced apoptosis of HPC cell may be by DNA damage, induction of cdk inhibitors (p21 and p27), and then subsequent stimulation of caspase-7 activation.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Proteínas de Ciclo Celular , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Ciclinas/metabolismo , Proteínas de Unión al ADN , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Naftoquinonas/farmacología , Neoplasias de la Próstata/metabolismo , Proteínas Supresoras de Tumor , Antioxidantes/farmacología , Apoptosis , Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Ciclinas/farmacología , Proteína Quinasa Activada por ADN , Inhibidores Enzimáticos/metabolismo , Fluoresceínas , Colorantes Fluorescentes , Genes Supresores de Tumor , Humanos , Masculino , Proteínas Asociadas a Microtúbulos/farmacología , Proteínas Nucleares , Fenantridinas , Poli(ADP-Ribosa) Polimerasas/metabolismo , Neoplasias de la Próstata/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Células Tumorales Cultivadas , Proteína Destructora del Antagonista Homólogo bcl-2
7.
J Nat Prod ; 63(12): 1608-10, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11141097

RESUMEN

Six novel dihydrophenanthrene derivatives, sinensols A-F (1-6), were isolated from the aerial parts of Spiranthesis sinensis. Their structures were determined on the basis of various spectroscopic data, in particular those yielded by MS and 2D NMR techniques.


Asunto(s)
Magnoliopsida/química , Fenantrenos/aislamiento & purificación , Estructura Molecular , Fenantrenos/química , Plantas Medicinales/química , Análisis Espectral
8.
J Nat Prod ; 61(12): 1531-4, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9868158

RESUMEN

Bioassay-directed fractionation of an EtOH extract of Curcuma zedoaria led to isolation of an active curcuminoid, which was identified as demethoxycurcumin (2) by comparison of its 1H and 13C NMR spectra with literature data and by direct comparison with synthetic material. Curcumin (1) and bisdemethoxycurcumin (3) were also obtained. Curcuminoids (1-3) were synthesized and demonstrated to be cytotoxic against human ovarian cancer OVCAR-3 cells. The observed CD50 values of 1, 2, and 3 were 4.4, 3.8, and 3.1 microg/mL, respectively. Three additional novel compounds, 3, 7-dimethylindan-5-carboxylic acid (4), curcolonol (5), and guaidiol (6), were also isolated from the EtOH extract. The structures and relative stereochemistry of 4-6 were determined by spectroscopic methods and X-ray crystallographic analysis.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Curcumina/farmacología , Plantas Medicinales/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , China , Cromatografía Líquida de Alta Presión , Cristalografía por Rayos X , Curcumina/análogos & derivados , Curcumina/aislamiento & purificación , Ensayos de Selección de Medicamentos Antitumorales , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Espectrofotometría Ultravioleta , Células Tumorales Cultivadas
9.
Free Radic Biol Med ; 24(4): 660-70, 1998 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-9559879

RESUMEN

Beta-Lapachone a novel topoisomerase inhibitor, has been found to induce apoptosis in various human cancer cells. In this study we report that a dramatic elevation of hydrogen peroxide (H2O2) in human leukemia HL-60 cells following 1 microM beta-lapachone treatment and that this increase was effectively inhibited by treatment with antioxidant N-acetyl-L-cysteine (NAC), ascorbic acid, alpha-tocopherol. NAC strongly prevented beta-lapachone-induced apoptotic characteristics such as DNA fragmentation and apoptotic morphology. However, treatment of HL-60 cells with another topoisomerase inhibitor camptothecin (CPT) did not induce H2O2 production as compared to untreated cells. NAC also failed to block CPT-induced apoptosis. Correlated with these findings, we found that cancer cell lines K562, MCF-7, and SW620, contained high level of intracellular glutathione (GSH), were not elevated in H2O2 and were resistant to apoptosis after treatment with beta-lapachone. In contrast, cancer cell lines such as, HL-60, U937, and Molt-4 which have lower level of GSH, were readily increased of H2O2 and were sensitive to this drug. Furthermore, ectopic overexpression of Bcl-2 in HL-60 cells also attenuated beta-lapachone-induced H2O2 and conferred resistance to beta-lapachone-induced cell death. Beta-Lapachone at the concentration as low as 0.25 microM effectively induced HL-60 cells to undergo monocytic differentiation, as evidenced by CD14 antigenicity and alpha-naphthyl acetate esterase activity. Again, the beta-lapachone-induced monocytic differentiation was suppressed by NAC. These results suggest that intracellular H2O2 generation plays a crucial role in beta-lapachone-induced cell death and differentiation.


Asunto(s)
Apoptosis , Diferenciación Celular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Peróxido de Hidrógeno/metabolismo , Leucemia Promielocítica Aguda/patología , Naftoquinonas/farmacología , Inhibidores de Topoisomerasa I , Acetilcisteína/farmacología , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Fragmentación del ADN , Resistencia a Medicamentos , Glutatión/metabolismo , Humanos , Monocitos , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Células Tumorales Cultivadas , Vitamina E/farmacología
10.
Histol Histopathol ; 13(1): 89-97, 1998 01.
Artículo en Inglés | MEDLINE | ID: mdl-9476638

RESUMEN

In present study we studied the cytotoxic effects of beta-lapachone, a potent anticancer drug, on the human hepatoma cell line (HepA2) under serum-free condition. Most cells died after 2 microM beta-lapachone addition at 48 hours. No apoptotic characteristics of DNA ladder was documented by agarose DNA electrophoresis. The blockage of cell cycle at S phase and unscheduled DNA synthesis were demonstrated by flow cytometric analysis and anti-bromodeoxyuridine immunocytochemistry. Ultrastructural observation showed that the swollen mitochondria, dilatation and vesiculation of rER and proliferation of peroxisome-like granules appeared within the cytoplasm of HepA2 cells following drug treatment. Using enzyme cytochemistry, both peroxidase and acid phosphatase activities but not catalase activity were localised in these peroxisome-like granules. Therefore, these results suggested that (a) beta-lapachone has a novel cytotoxic effect on human hepatoma cell; (2) beta-lapachone induces the interruption of the cell cycle and unscheduled DNA synthesis in HepA2 cells; and (3) beta-lapachone promotes the proliferation of peroxisome-like granules containing peroxidase and acid phosphatase activities without evidence of catalase activity in hepatoma cell line.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Naftoquinonas/farmacología , Gránulos Citoplasmáticos/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Humanos , Microcuerpos/efectos de los fármacos , Fase S/efectos de los fármacos , Células Tumorales Cultivadas
11.
J Nat Prod ; 59(3): 330-3, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8882438

RESUMEN

The antiviral activity in the roots of Rubia cordifolia was examined, and three naphthohydroquinones, furomollugin (1), mollugin (2), and rubilactone (3), were isolated from it. Compounds 1 and 2 strongly suppressed the secretion of hepatitis B surface antigen (HBsAg), both with IC50 = 2.0 micrograms/mL, in human hepatoma Hep3B cells while having little effect on the viability of the cells. Evaluation of structurally related derivatives of 1 and 2 revealed that a 6-hydroxy group and a pyran or furan ring contribute to this suppressive effect.


Asunto(s)
Antivirales/farmacología , Medicamentos Herbarios Chinos/farmacología , Antígenos de Superficie de la Hepatitis B/inmunología , Neoplasias Hepáticas Experimentales/metabolismo , Naftoles/aislamiento & purificación , Naftoles/farmacología , Piranos/aislamiento & purificación , Pironas/aislamiento & purificación , Pironas/farmacología , Animales , Antivirales/química , Medicamentos Herbarios Chinos/química , Humanos , Naftoles/química , Piranos/farmacología , Pironas/química , Células Tumorales Cultivadas
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