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1.
Sci Rep ; 11(1): 10611, 2021 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-34012003

RESUMEN

The first synthetic cannabinoid receptor agonists (SCRAs) were designed as tool compounds to study the endocannabinoid system's two predominant cannabinoid receptors, CB1R and CB2R. Unfortunately, novel SCRAs now represent the most rapidly proliferating novel psychoactive substances (NPS) of abuse globally. Unlike ∆9-tetrahydrocannabinol, the CB1R and CB2R partial agonist and the intoxicating constituent of Cannabis, many SCRAs characterized to date are full agonists of CB1R. Gaining additional insight into the pharmacological activity of these SCRAs is critical to assess and regulate NPSs as they enter the marketplace. The purpose of this study was to assess select SCRAs recently identified by Canadian police, border service agency, private companies and the illicit market as potential CB1R and CB2R agonists. To this end, fifteen SCRAs were screened for in vitro activity and in silico interactions at CB1R and CB2R. Several SCRAs were identified as being highly biased for cAMP inhibition or ßarrestin2 recruitment and receptor subtype selectivity between CB1R and CB2R. The indazole ring and halogen-substituted butyl or pentyl moieties were identified as two structural features that may direct ßarrestin2 bias. Two highly-biased SCRAs-JWH-018 2'-napthyl-N-(3-methylbutyl) isomer (biased toward cAMP inhibition) and 4-fluoro MDMB-BINACA (biased toward ßarrestin2 recruitment) displayed unique and differential in vivo activity in mice. These data provide initial insight into the correlations between structure, signalling bias, and in vivo activity of the SCRAs.


Asunto(s)
Agonistas de Receptores de Cannabinoides/farmacología , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/metabolismo , Animales , Temperatura Corporal , Células CHO , Agonistas de Receptores de Cannabinoides/química , Catalepsia , Colforsina/farmacología , Cricetulus , AMP Cíclico/metabolismo , Humanos , Masculino , Ratones Endogámicos C57BL , Modelos Moleculares , Nocicepción/efectos de los fármacos , Arrestina beta 2/metabolismo
2.
Sci Rep ; 10(1): 20405, 2020 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-33230154

RESUMEN

The Cannabis sativa plant contains more than 120 cannabinoids. With the exceptions of ∆9-tetrahydrocannabinol (∆9-THC) and cannabidiol (CBD), comparatively little is known about the pharmacology of the less-abundant plant-derived (phyto) cannabinoids. The best-studied transducers of cannabinoid-dependent effects are type 1 and type 2 cannabinoid receptors (CB1R, CB2R). Partial agonism of CB1R by ∆9-THC is known to bring about the 'high' associated with Cannabis use, as well as the pain-, appetite-, and anxiety-modulating effects that are potentially therapeutic. CB2R activation by certain cannabinoids has been associated with anti-inflammatory activities. We assessed the activity of 8 phytocannabinoids at human CB1R, and CB2R in Chinese hamster ovary (CHO) cells stably expressing these receptors and in C57BL/6 mice in an attempt to better understand their pharmacodynamics. Specifically, ∆9-THC, ∆9-tetrahydrocannabinolic acid (∆9-THCa), ∆9-tetrahydrocannabivarin (THCV), CBD, cannabidiolic acid (CBDa), cannabidivarin (CBDV), cannabigerol (CBG), and cannabichromene (CBC) were evaluated. Compounds were assessed for their affinity to receptors, ability to inhibit cAMP accumulation, ßarrestin2 recruitment, receptor selectivity, and ligand bias in cell culture; and cataleptic, hypothermic, anti-nociceptive, hypolocomotive, and anxiolytic effects in mice. Our data reveal partial agonist activity for many phytocannabinoids tested at CB1R and/or CB2R, as well as in vivo responses often associated with activation of CB1R. These data build on the growing body of literature showing cannabinoid receptor-dependent pharmacology for these less-abundant phytocannabinoids and are critical in understanding the complex and interactive pharmacology of Cannabis-derived molecules.


Asunto(s)
Analgésicos/farmacología , Ansiolíticos/farmacología , Agonistas de Receptores de Cannabinoides/farmacología , Cannabis/química , Psicotrópicos/farmacología , Receptor Cannabinoide CB1/genética , Receptor Cannabinoide CB2/genética , Analgésicos/aislamiento & purificación , Animales , Ansiolíticos/aislamiento & purificación , Células CHO , Cannabidiol/aislamiento & purificación , Cannabidiol/farmacología , Agonistas de Receptores de Cannabinoides/aislamiento & purificación , Cannabinoides/aislamiento & purificación , Cannabinoides/farmacología , Cricetulus , Dronabinol/análogos & derivados , Dronabinol/aislamiento & purificación , Dronabinol/farmacología , Expresión Génica , Humanos , Ratones Endogámicos C57BL , Extractos Vegetales/química , Psicotrópicos/aislamiento & purificación , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/agonistas , Receptor Cannabinoide CB2/metabolismo , Transgenes , Arrestina beta 2/genética , Arrestina beta 2/metabolismo
3.
J Nanosci Nanotechnol ; 20(11): 7145-7150, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32604573

RESUMEN

The effects of a plasma treatment on the sensing performance of surface acoustic wave (SAW) sensors to detect chemical warfare agents (CWAs) were investigated. SAW sensors designed for an operating frequency of 250 MHz were fabricated using lift-off techniques followed by the deposition of a very thin thiourea (TU) layer as a sensing film on the sensing area of the SAW sensor. To achieve some advantages from the plasma treatment on the surface, such as cleaning, surface activation and modification, a post-plasma treatment was performed on the sensing layer and the sensing performance of the SAW sensor was measured by a comparison with the measured responses, providing different simulant gases through the gas feeding system. The sensitivity test revealed significant improvement in the sensing ability of the SAW sensor to detect DMMP, a simulant of a CWA, but with a relatively longer recovery time. The responses of other simulants at different concentrations and different simulant vapors were compared. The results showed that a plasma treatment on the sensing layer of a SAW device can improve the selectivity and sensitivity to a certain target gas or some volatile organic compounds. Therefore, a plasma treatment will be very useful for improving the selectivity and sensitivity of SAW sensors for the detection of CWAs.

4.
J Nanosci Nanotechnol ; 20(11): 7151-7157, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32604574

RESUMEN

Recently, efforts have been made to adapt surface acoustic waves (SAWs) for use in chemical sensors for detection of chemical warfare agents (CWAs). In this study, a four-channel real-time CWA detection system was constructed using four 250-MHz SAW sensors. Each system consists of three different chemical sensors and one reference sensor. The reference sensor compensates for frequency variations according to humidity and temperature conditions. Signals from the SAW sensors can be checked on a PC-based graphical user interface without additional measuring equipment. To measure dimethyl methylphosphonate (DMMP), a simulant of sarin gas, polyhedral oligomeric silsesquioxane (POSS) and thiourea (TU)-based synthetic polymers were used as sensing materials. The reference sensor was not coated, whereas the three different chemical sensors were coated with POSS, TU-1, and TU-2. The maximum frequencies of POSS, TU-1, and TU-2 were shifted 15.86, 13.85, and 0.944 kHz, showing significant values. We also found a relatively good linear relation between the frequency shift and the concentration of DMMP. The three sensing materials selected-POSS, TU-1, and TU-2-responded significantly to DMMP and triethylphosphate in the selectivity tests. This response is due to the chemical bonding of the sensing materials with the phosphonate in the nerve-agent simulants. These results indicate that the four-channel SAW monitoring system described in this paper shows potential as a portable real-time monitoring system to detect a variety of toxic vapors simultaneously, without using complex measuring equipment. In addition, this approach has demonstrated potential for developing excellent portable sensors to detect different types of CWAs.

5.
Korean J Physiol Pharmacol ; 18(4): 307-11, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25177162

RESUMEN

In this study, we isolated scopoletin from Cirsium setidens Nakai (Compositae) and tested its effects on melanogenesis. Scopoletin was not toxic to cells at concentrations less than 50 µM and increased melanin synthesis in a dose-dependent manner. As melanin synthesis increased, scopoletin stimulated the total tyrosinase activity, the rate-limiting enzyme of melanogenesis. In a cell-free system, however, scopoletin did not increase tyrosinase activity, indicating that scopoletin is not a direct activator of tyrosinase. Furthermore, Western blot analysis showed that scopoletin stimulated the production of microphthalmia-associated transcription factor (MITF) and tyrosinase expression via cAMP response element-binding protein (CREB) phosphorylation in a dose-dependent manner. Based on these results, preclinical and clinical studies are needed to assess the use of scopoletin for the treatment of vitiligo.

6.
Eur J Pharmacol ; 718(1-3): 299-304, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-24012927

RESUMEN

Menadione is a synthetic vitamin K3 derivative. Here, we examined the effects of menadione on melanogenesis and its related signaling pathways. Our results showed that melanin content was significantly reduced after menadione treatment in a dose-dependent manner. However, menadione treatment did not reduce tyrosinase activity directly. Wnt signaling is known to play a major role in the control of melanin synthesis. Thus, we tested the effects of menadione treatment on GSK3ß and ß-catenin signaling, but found that menadione did not influence either of these signaling pathways. We also investigated changes in the phosphorylation of ERK, which is related to melanin regulation. These results indicated that menadione treatment led to the phosphorylation of ERK. Additionally, menadione treatment reduced both MITF and tyrosinase protein levels. Treatment with PD98059, a specific ERK pathway inhibitor, restored menadione-induced melanin reduction and also prevented MITF and tyrosinase downregulation by menadione. These results suggest that the hypopigmentary action of menadione is due to MITF and tyrosinase downregulation by ERK activation.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Melaninas/biosíntesis , Vitamina K 3/farmacología , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Flavonoides/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Hipopigmentación/enzimología , Hipopigmentación/metabolismo , Hipopigmentación/patología , Ratones , Factor de Transcripción Asociado a Microftalmía/metabolismo , Monofenol Monooxigenasa/metabolismo , Fosforilación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
7.
Eur J Med Genet ; 56(10): 561-5, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23832104

RESUMEN

Langer-Giedion syndrome (LGS; MIM 150230), also called trichorhinophalangeal syndrome type II (TRPS2), is a contiguous gene syndrome caused by a one-copy deletion in the chromosome 8q23-q24 region, spanning the genes TRPS1 and EXT1. We identified an LGS family with two affected and two unaffected siblings from unaffected parents. To investigate the etiology of recurrence of LGS in this family, array CGH was performed on all family members. We identified a 7.29 Mb interstitial deletion at chromosome region 8q23-q24 in the two affected siblings, but no such deletion in the unaffected family members. However, the mother and one of the two unaffected siblings carried a 1.29 Mb deletion at chromosome region 8q24.1, sharing the distal breakpoint with the larger deleted segment found in the affected siblings. Another unaffected sibling had a 6.0 Mb duplication, sharing the proximal breakpoint of the deletion in the affected siblings. Karyotypic and FISH analyses in the unaffected mother revealed an insertional translocation of 8q23-q24 genomic material into chromosome 13: 46,XX,ins(13;8)(q33;q23q24). This insertional translocation in the mother results in the recurrence of LGS in this family, highlighting the importance of submicroscopic rearrangements in the genetic counseling for LGS.


Asunto(s)
Síndrome de Langer-Giedion/genética , Mutagénesis Insercional , Cariotipo Anormal , Adolescente , Secuencia de Bases , Rotura Cromosómica , Cromosomas Humanos Par 8/genética , Hibridación Genómica Comparativa , Análisis Mutacional de ADN , Femenino , Estudios de Asociación Genética , Humanos , Síndrome de Langer-Giedion/diagnóstico por imagen , Masculino , Polimorfismo de Nucleótido Simple , Radiografía , Eliminación de Secuencia , Adulto Joven
8.
Life Sci ; 93(5-6): 226-32, 2013 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-23792203

RESUMEN

AIMS: Geranylgeranylacetone (GGA) has shown cytoprotective activity through induction of a 70-kDa heat shock protein (HSP70). Although HSP70 is reported to regulate melanogenesis, the effects of GGA on melanin synthesis in melanocytes have not been previously studied. Therefore, this study investigated the effects of GGA on melanogenesis and the related signaling pathways. MAIN METHODS: Melanin content and tyrosinase activities were measured in Mel-Ab cells. GGA-induced signal transduction pathways were investigated by western blot analysis. KEY FINDINGS: Our results showed that GGA significantly decreased melanin content in a concentration-dependent manner. Similarly, GGA reduced tyrosinase activity dose-dependently, but it did not directly inhibit tyrosinase. Western blot analysis indicated that GGA downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase protein expression, whereas it increased the phosphorylation of extracellular signal-regulated kinase (ERK) and mammalian target of rapamycin (mTOR). Furthermore, a specific ERK pathway inhibitor, PD98059, blocked GGA-induced melanin reduction and then prevented downregulation of MITF and tyrosinase by GGA. However, a specific mTOR inhibitor, rapamycin, only slightly restored inhibition of melanin production by GGA, indicating that mTOR signaling is not a key mechanism regulating the inhibition of melanin production. SIGNIFICANCE: These findings suggest that activation of ERK by GGA reduces melanin synthesis in Mel-Ab cells through downregulation of MITF and tyrosinase expression.


Asunto(s)
Antineoplásicos/farmacología , Diterpenos/farmacología , Quinasas MAP Reguladas por Señal Extracelular/fisiología , Melaninas/antagonistas & inhibidores , Melaninas/biosíntesis , Melanocitos/efectos de los fármacos , Melanocitos/enzimología , Transducción de Señal/efectos de los fármacos , Animales , Línea Celular Transformada , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/fisiología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Melanocitos/patología , Ratones , Transducción de Señal/fisiología
9.
Korean J Physiol Pharmacol ; 16(4): 287-91, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22915995

RESUMEN

This study investigated the effects of proline-serine (PS) and valine-serine (VS) dipeptides on melanogenesis in Mel-Ab cells. Proline-serine and VS significantly inhibited melanin synthesis in a concentration-dependent manner, though neither dipeptide directly inhibited tyrosinase activity in a cell-free system. Both PS and VS down-regulated the expression of microphthalmia-associated transcription factor (MITF) and tyrosinase. In a follow-up study also described here, the effects of these dipeptides on melanogenesis-related signal transduction were quantified. Specifically, PS and VS induced ERK phosphorylation, though they had no effect on phosphorylation of the cAMP response element binding protein (CREB). These data suggest that PS and VS inhibit melanogenesis through ERK phosphorylation and subsequent down-regulation of MITF and tyrosinase. Properties of these dipeptides are compatible with application as skin-whitening agents.

10.
Cancer Nurs ; 34(5): 376-84, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21242774

RESUMEN

BACKGROUND: Care coordination has received increased attention in recent years because it critically affects patient safety and care quality across services and settings. OBJECTIVE: The effectiveness of systematically developed nurse navigator interventions for newly diagnosed cancer patients was evaluated. METHODS: Seventy-eight patients participated in a nonequivalent control group pretest-posttest design study. The study design spanned a 3-month period for all participants. Patient outcome measures included quality of life, satisfaction with care, and length of hospital stay. RESULTS: Participants in the experimental program reported significant increases in several components of quality of life and with satisfaction with care and experienced fewer hospital stay days compared with the control group. CONCLUSION: This study provides evidence that standardized nurse navigator programs can improve patient outcomes in cancer care. IMPLICATIONS FOR PRACTICE: Positive outcomes of the reduced length of stay and improved quality of life and patient satisfaction may help transform the cancer care delivery model toward more nurse-initiated cost-effective model.


Asunto(s)
Neoplasias/enfermería , Investigación en Evaluación de Enfermería , Enfermería Oncológica , Evaluación de Resultado en la Atención de Salud , Atención Dirigida al Paciente/métodos , Adulto , Anciano , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Enfermería Oncológica/organización & administración , Satisfacción del Paciente/estadística & datos numéricos , Atención Dirigida al Paciente/organización & administración , Calidad de Vida
11.
Neurosci Lett ; 433(3): 199-204, 2008 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-18242851

RESUMEN

Whether modulation of C afferent fiber activities could relieve peripheral neuropathic pain was tested. After establishment of neuropathic pain induced by L5 and 6 spinal nerve transection (SNT), the sciatic nerve was treated with 2% capsaicin at the level of the midthigh. Mechanical hyperalgesia (von Frey filaments) was significantly alleviated from 7 days to 4 weeks after capsaicin treatment, but cold allodynia (acetone) was unchanged. Immunohistochemical studies showed a significant increase in the number of calcitonin gene-related peptide (CGRP)-positive neurons, but not TRPV1-positive neurons in intact L4 dorsal root ganglia after SNT. Capsaicin treatment decreased TRPV1- and CGRP-positive neurons in L4 DRG of the treated side, but not the opposite side. These results suggest that local application of capsaicin onto the sciatic nerve can alleviate mechanical hyperalgesia, but not cold allodynia, in a peripheral neuropathic pain model and the pain alleviation may result from a decrease of TRPV1- and CGRP-positive sensory neurons of which fibers pass through the sciatic nerve.


Asunto(s)
Capsaicina/farmacología , Hiperalgesia/tratamiento farmacológico , Neuralgia/tratamiento farmacológico , Traumatismos de los Nervios Periféricos , Nervios Periféricos/efectos de los fármacos , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Analgésicos/farmacología , Animales , Biomarcadores/análisis , Biomarcadores/metabolismo , Péptido Relacionado con Gen de Calcitonina/metabolismo , Recuento de Células , Desnervación , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Ganglios Espinales/fisiopatología , Hiperalgesia/metabolismo , Hiperalgesia/fisiopatología , Masculino , Degeneración Nerviosa/metabolismo , Degeneración Nerviosa/fisiopatología , Neuralgia/metabolismo , Neuralgia/fisiopatología , Neuronas Aferentes/efectos de los fármacos , Neuronas Aferentes/metabolismo , Dimensión del Dolor , Nervios Periféricos/fisiopatología , Enfermedades del Sistema Nervioso Periférico/metabolismo , Enfermedades del Sistema Nervioso Periférico/fisiopatología , Estimulación Física , Ratas , Ratas Sprague-Dawley , Fármacos del Sistema Sensorial/farmacología , Canales Catiónicos TRPV/metabolismo
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