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1.
Mol Genet Genomics ; 294(1): 211-226, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30293092

RESUMEN

Giant-Skippers (Megathymini) are unusual thick-bodied, moth-like butterflies whose caterpillars feed inside Yucca roots and Agave leaves. Giant-Skippers are attributed to the subfamily Hesperiinae and they are endemic to southern and mostly desert regions of the North American continent. To shed light on the genotypic determinants of their unusual phenotypic traits, we sequenced and annotated a draft genome of the largest Giant-Skipper species, the Bear (Megathymus ursus violae). The Bear skipper genome is the least heterozygous among sequenced Lepidoptera genomes, possibly due to much smaller population size and extensive inbreeding. Their lower heterozygosity helped us to obtain a high-quality genome with an N50 of 4.2 Mbp. The ~ 430 Mb genome encodes about 14000 proteins. Phylogenetic analysis supports placement of Giant-Skippers with Grass-Skippers (Hesperiinae). We find that proteins involved in odorant and taste sensing as well as in oxidative reactions have diverged significantly in Megathymus as compared to Lerema, another Grass-Skipper. In addition, the Giant-Skipper has lost several odorant and gustatory receptors and possesses many fewer (1/3-1/2 of other skippers) anti-oxidative enzymes. Such differences may be related to the unusual life style of Giant-Skippers: they do not feed as adults, and their caterpillars feed inside Yuccas and Agaves, which provide a source of antioxidants such as polyphenols.


Asunto(s)
Genoma de los Insectos , Mariposas Nocturnas/genética , Análisis de Secuencia de ADN/métodos , Yucca/parasitología , Animales , Tamaño del Genoma , Mariposas Nocturnas/fisiología , Fenotipo , Filogenia , Raíces de Plantas/parasitología
2.
Planta Med ; 80(18): 1732-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25377118

RESUMEN

In our efforts to find an inhibitor of melanin formation and develop potential depigmenting agents for skin-protecting cosmetics and medicinal products from natural resources, we focused on the seeds of Crataegus pinnatifida which showed antioxidant and tyrosinase-inhibiting activities. By activity-guided fractionation of an extract of C. pinnatifida seeds, four new neolignan glycosides, pinnatifidaninsides A-D (1-4), along with two known compounds (5-6), were isolated. Their structures were elucidated by spectroscopic analyses, especially 1D, 2D NMR and CD spectra. The antioxidant and tyrosinase-inhibiting activities of all isolates were assayed. Compound 6 showed good activity against 2,2-diphenyl-1-pikrylhydrazyl, while compounds 1, 2, 5, and 6 exhibited strong 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) free radical scavenging activity, being as effective as, or even more effective than the positive control Trolox. Moreover, compounds 5 and 6 displayed a moderate mushroom tyrosinase inhibitory activity.


Asunto(s)
Antioxidantes/farmacología , Crataegus/química , Inhibidores Enzimáticos/farmacología , Glicósidos/química , Lignanos/química , Monofenol Monooxigenasa/antagonistas & inhibidores , Evaluación Preclínica de Medicamentos/métodos , Inhibidores Enzimáticos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Monofenol Monooxigenasa/metabolismo , Semillas/química , Relación Estructura-Actividad
3.
Zhongguo Zhen Jiu ; 31(4): 305-8, 2011 Apr.
Artículo en Chino | MEDLINE | ID: mdl-21528594

RESUMEN

OBJECTIVE: To compare the time-effect rule of pain-relieving in moderate dysmenorrhea in the treatment between acupuncture on single-point and acupuncture on multi-point so as to determine the best time of needle retaining on single-point and multi-point as well as provide the reference evidences of acupuncture frequency in the treatment. METHODS: Sixty-three cases of moderate dysmenorrhea were randomized into a single-point group (31 cases) and a multi-point group (32 cases). During the attack of dysmenorrhea, in single-point group, Shiqizhui (EX-B 8) was punctured; in multi-point group, Shiqizhui (EX-B 8), Diji (SP 8), Ciliao (BL 32) and Sanyinjiao (SP 6) were punctured and the needles were retained for 30 min. Visual Analogue Scale (VAS) values were recorded in the immediate time before acupuncture, in 5 min, 10 min, 20 min and 30 min after needle insertion, as well as in 30 min, 60 min and 120 min after needle withdrawal separately. RESULTS: After needling, analgesia was generated rapidly in either group. During 30 min of needle retaining, analgesia was enhanced persistently till needle withdrawal in either group. In 10 min after needle insertion, the immediate analgesia in multi-point group was superior obviously to single-point group (P < 0.05) and this effect was maintained in 2 h after needle withdrawal. In 30 min after needle withdrawal, acupuncture analgesia was declined to the maximum. CONCLUSION: Either single-point acupuncture at Shiqizhui (EX-B 8) or multi-point acupuncture at Shiqizhui (EX-B 8) and other acupoints has apparent immediate analgesia on primary dysmenorrhea of moderate degree, but the effect of multi-point acupuncture is better than that of acupuncture at Shiqizhui (EX-B 8). No matter with acupuncture at Shiqizhui (EX-B 8) or at multi-point, the time of needle retaining should not be shorten than 30 min. It is suitable to give acupuncture, twice per day for the patients with moderate and persistent pain.


Asunto(s)
Analgesia por Acupuntura , Puntos de Acupuntura , Dismenorrea/terapia , Manejo del Dolor , Adolescente , Adulto , Femenino , Humanos , Adulto Joven
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(3): 656-60, 2009 Mar.
Artículo en Chino | MEDLINE | ID: mdl-19455793

RESUMEN

In the present study, 40 samples of ginsengs (20 samples from Jian and 20 samples from Fushun) were surveyed by Fourier transform infrared (IR) spectroscopy. Meanwhile, in order to eliminate the spectral differences from the baseline drifts, the original ginseng spectra were processed using first derivative method. To avoid enhancing the noise resulting from the derivative the spectra were smoothed. This smoothing was done by using the Savitzky-Golay algorithm, a moving window averaging method. Artificial neural network (ANN), support vector machine (SVM) as the new pattern recognition technology, and wavelet transform (WT) were applied. Firstly, the spectrum variables of infrared spectroscopy were compressed through the WT technology before the models were established, in order to reduce the time in establishing models. Then, the identification models of cultivation area of ginsengs were studied comparatively by the use of ANN and SVM methods. The corresponding important parameters of models were also discussed in detail, including the parameters of wavelet compressing and training parameters of ANN and SVM models. The simulation experiment indicated that the ANN model can carry on the distinction among 40 samples of ginsengs from Jilin, and the accuracy rate of identification was 92.5%. The radial basis function (RBF) SVM classifiers and the polynomial SVM classifiers were studied comparatively in this experiment. The best experimental results were obtained using RBF SVM classifier with sigma = 0.6, and the accuracy rate of identification was 97.5%. Finally, compared with ANN approach, SVM algorithm showed its excellent generalization for identification results while the number of samples was smaller. The overall results show that IR spectroscopy combined with SVM and WT technology can be efficiently utilized for rapid and simple identification of the cultivation area of ginsengs, and thus provides the certain technology support and the foundation for further researching ginseng and other IR applications.


Asunto(s)
Inteligencia Artificial , Panax/química , Algoritmos , Redes Neurales de la Computación , Espectroscopía Infrarroja por Transformada de Fourier
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