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1.
J Econ Entomol ; 108(3): 925-32, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26470212

RESUMEN

The insecticidal and repellent activities of the essential oil extracted from Zingiber purpureum Roscoe rhizomes were evaluated against Tribolium castaneum (Herbst) and Lasioderma serricorne (L.) adults. During our screening program for agrochemicals from Chinese medicinal herbs and wild plants, the essential oil of Z. purpureum rhizomes was found to possess strong contact toxicity against T. castaneum and L. serricorne adults, with LD50 values of 39.0 and 16.3 µg per adult, respectively, and also showed strong fumigant toxicity against the two grain storage insects with LC50 values of 13.6 and 9.3 mg/liter of air, respectively. The essential oil obtained by hydrodistillation was investigated by gas chromatography-mass spectrometry. The main components of the essential oil were identified to be sabinene (48.1%), terpinen-4-ol (25.1%), and γ-terpinene (6.7%), followed by α-terpinene (4.3%), ß-thujene (3.4%), and α-phellandrene (2.7%). Sabinene, terpinen-4-ol, and γ-terpinene were separated and purified by silica gel column chromatography and preparative thin-layer chromatography. Terpinen-4-ol showed the strongest contact toxicity against T. castaneum and L. serricorne (LD50=19.7 and 5.4 µg per adult, respectively) and also the strongest fumigant toxicity against T. castaneum and L. serricorne (LC50=3.7 and 1.3 mg/liter of air, respectively). Otherwise, sabinene and terpinen-4-ol were strongly repellent against T. castaneum as well as the essential oil, while γ-terpinene exhibited weaker repellency against T. castaneum compared with the positive control, DEET (N, N-diethyl-3-methylbenzamide). Moreover, only the essential oil exhibited strong repellency against L. serricorne, the three compounds exhibited weaker repellency against L. serricorne relative to DEET.


Asunto(s)
Escarabajos , Insecticidas , Aceites Volátiles , Zingiberaceae/química , Animales , Extractos Vegetales/química , Rizoma/química
2.
Tree Physiol ; 35(12): 1343-55, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26358048

RESUMEN

During periods of water deficit, growing roots may shrink, retaining only partial contact with the soil. In this study, known mathematical models were used to calculate the root-soil air gap and water flow resistance at the soil-root interface, respectively, of Robinia pseudoacacia L. under different water conditions. Using a digital camera, the root-soil air gap of R. pseudoacacia was investigated in a root growth chamber; this root-soil air gap and the model-inferred water flow resistance at the soil-root interface were compared with predictions based on a separate outdoor experiment. The results indicated progressively greater root shrinkage and loss of root-soil contact with decreasing soil water potential. The average widths of the root-soil air gap for R. pseudoacacia in open fields and in the root growth chamber were 0.24 and 0.39 mm, respectively. The resistance to water flow at the soil-root interface in both environments increased with decreasing soil water potential. Stepwise regression analysis demonstrated that soil water potential and soil temperature were the best predictors of variation in the root-soil air gap. A combination of soil water potential, soil temperature, root-air water potential difference and soil-root water potential difference best predicted the resistance to water flow at the soil-root interface.


Asunto(s)
Rizosfera , Robinia/metabolismo , Suelo/química , Agua/metabolismo , Modelos Biológicos , Raíces de Plantas/metabolismo , Temperatura
3.
Acta Pharmacol Sin ; 22(2): 132-6, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11741517

RESUMEN

AIM: To investigate whether allitridum has the effect of pharmacological preconditioning and whether protein kinase C (PKC) plays a role in myocardial protection. METHODS: Thirty-four isolated rabbit hearts which subjected to 30 min of regional myocardial ischemia and 2 h reperfusion, were randomly divided into 5 groups: control group, ischemic preconditioning (PC) group, allitridum (A) group, polymyxin B (Poly B) group, allitridum + polymyxin B (A + Poly B) group. Infarct size was determined by triphenyltetrazolium staining. RESULTS: Pharmacological preconditioning in hearts with a 5 -min allitridum infusion 10 min before the prolonged regional ischemia resulted in significantly smaller infarcts (7 % +\- 6 % of risk area) than in control hearts (25 % +\- 7 %, P < 0.05). There is no significant difference in infarct size between (A+Poly B) group and control hearts (23 % +\- 5 % vs 25 % +\- 7 %, P > 0.05). CONCLUSION: These data indicate that allitridum can precondition rabbit ischemic myocardium and this protection can be effectively blocked by administration of Poly B, an inhibitor of PKC, implying that PKC has an important role in preconditioning.


Asunto(s)
Compuestos Alílicos/farmacología , Precondicionamiento Isquémico Miocárdico , Proteína Quinasa C , Sulfuros/farmacología , Compuestos Alílicos/aislamiento & purificación , Animales , Activación Enzimática , Femenino , Ajo/química , Técnicas In Vitro , Masculino , Isquemia Miocárdica/patología , Polimixina B/farmacología , Proteína Quinasa C/fisiología , Conejos , Sulfuros/aislamiento & purificación
4.
Proc Natl Acad Sci U S A ; 95(16): 9155-60, 1998 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-9689050

RESUMEN

The importance of alternative splicing in regulating apoptosis has been suggested by findings of functionally antagonistic proteins generated by alternative splicing of several genes involved in apoptosis. Among these, Ich-1 (also named as caspase-2) encodes a member of the caspase family of proteases. Two forms of Ich-1 are produced as a result of alternative splicing: Ich-1L, which causes apoptosis, and Ich-1S, which prevents apoptosis. The precise nature of Ich-1 alternative splicing and its regulation remain unknown. Here, we show that the production of Ich-1L and Ich-1S transcripts results from alternative exclusion or inclusion of a 61-bp exon. Several splicing factors can regulate Ich-1 splicing. Serine-arginine-rich proteins SC35 and ASF/SF2 promote exon skipping, decreasing the ratio of Ich-1S to Ich-1L transcripts; whereas heterogeneous nuclear ribonucleoprotein A1 facilitates exon inclusion, increasing this ratio. Furthermore, in cultured cells, SC35 overexpression increases apoptosis; whereas heterogeneous nuclear ribonucleoprotein A1 overexpression decreases apoptosis. These results provide the first direct evidence that splicing factors can regulate Ich-1 alternative splicing and suggest that alternative splicing may be an important regulatory mechanism for apoptosis.


Asunto(s)
Empalme Alternativo , Apoptosis , Caspasas , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B , Proteínas/genética , Precursores del ARN/genética , ARN Mensajero/genética , Animales , Arginina/metabolismo , Secuencia de Bases , Caspasa 2 , Línea Celular , ADN Complementario , Ribonucleoproteína Nuclear Heterogénea A1 , Ribonucleoproteínas Nucleares Heterogéneas , Humanos , Ratones , Datos de Secuencia Molecular , Ribonucleoproteínas/genética , Homología de Secuencia de Ácido Nucleico , Serina/metabolismo
5.
J Vasc Res ; 34(4): 273-80, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9256087

RESUMEN

We have investigated whether the saponin astragaloside IV (AS-IV), a 3-O-beta-D-xylopyranosyl-6-O-beta-D-glucopyranosylcycloastragenol, purified from the Chinese herb drug Astragalus membranaceus, which is used in traditional Chinese medicine to treat cardiovascular diseases, might affect the fibrinolytic potential of cultured human umbilical vein endothelial cells (HUVECs). When HUVECs were conditioned with AS-IV, a dose (0.01-100 microg AS-IV/ml)- and time-dependent decrease in plasminogen activator inhibitor type 1 (PAI-1) and an increase in tissue-type plasminogen activator (t-PA) synthesis were observed, which were significant from 1 microg AS-IV/ml and from 12 h of incubation with 100 microg AS-IV/ml. PAI-1 antigen decreased from 641 +/- 86 to 318 +/- 18 ng/10(5) cells/24 h, whereas t-PA antigen increased from 4.1 +/- 0.3 to 9.7 +/- 0.4 ng/10(5) cells/24 h after addition of 100 microg AS-IV/ml. PAI-1 activity decreased to 30% of control level, whereas t-PA activity and t-PA-PAI-1 complexes reached a maximum stimulation of 3- and 5-fold over control levels, respectively, in the conditioned media of HUVECs treated with 100 microg AS-IV/ml for 24 h. PAI-1-specific mRNA expression decreased to 55% (2.2 kb) and 72% (3.2 kb), 66% (2.2 kb) and 88% (3.2 kb), and 19% (2.2 kb) and 41% (3.2 kb) of control values after incubation for 6, 12 and 18 h, respectively, whereas t-PA-specific mRNA increased 2-, 2.5- and 1.4-fold in HUVECs treated with 100 microg/ml AS-IV for 6, 12, and 18 h, respectively. In conclusion our data give evidence that in fact AS-IV can increase the fibrinolytic potential of cultured HUVECs not only by upregulating the expression of t-PA as NG-R1 does, but also by downregulating the expression of PAI-1.


Asunto(s)
Endotelio Vascular/enzimología , Glucósidos/farmacología , Inhibidor 1 de Activador Plasminogénico/metabolismo , Saponinas/farmacología , Activador de Tejido Plasminógeno/metabolismo , Triterpenos , Antihipertensivos/farmacología , Astragalus propinquus , Northern Blotting , Células Cultivadas , Regulación hacia Abajo , Medicamentos Herbarios Chinos/farmacología , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Fibrinólisis , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , ARN Mensajero/genética , Venas Umbilicales/citología , Regulación hacia Arriba
6.
Zhongguo Zhong Yao Za Zhi ; 19(9): 532-4, 574, 1994 Sep.
Artículo en Chino | MEDLINE | ID: mdl-7811363

RESUMEN

A study on the anti-mold activity of BCM, cinnamaldehyde and clove oil, was made by means of ultramicrostructural observation. The results show that both cinnamaldehyde and clove oil have strong anti-mold activity, (the former being even stronger), while BCM works well only in cases of Aspergillus, Penicillium and Trichoderma. SME and TME have found out that cinnamaldehyde is able to destroy the wall of fungal cells, the coagulate plasma and dissolve the cell organs.


Asunto(s)
Acroleína/análogos & derivados , Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Penicillium/efectos de los fármacos , Acroleína/farmacología , Almacenaje de Medicamentos , Eugenol/farmacología , Trichoderma/efectos de los fármacos
7.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 14(8): 462-4, 1994 Aug.
Artículo en Chino | MEDLINE | ID: mdl-7841752

RESUMEN

A simultaneously comparative study on pulmonary artery compliance (Cpa) and pulmonary artery mean pressure (PAMP) in 89 patients with Lung-Distention in TCM by impedance pulmonary rheogram, tricuspid valve echocardiogram and right heart catheterization. Then according to Syndrome Differentiation of TCM, Lung-Distention was sub-divided into four groups. The results showed that PAMP were gradually increased and Cpa decreased in these groups. It revealed that the pulmonary circulation of Lung-Distention patients has disturbed.


Asunto(s)
Rendimiento Pulmonar , Enfermedades Pulmonares Obstructivas/fisiopatología , Medicina Tradicional China , Circulación Pulmonar , Adulto , Anciano , Presión Sanguínea , Diagnóstico Diferencial , Femenino , Hemodinámica , Humanos , Enfermedades Pulmonares Obstructivas/complicaciones , Masculino , Persona de Mediana Edad , Arteria Pulmonar/fisiopatología , Enfermedad Cardiopulmonar/fisiopatología
8.
Zhongguo Yao Li Xue Bao ; 15(2): 173-6, 1994 Mar.
Artículo en Chino | MEDLINE | ID: mdl-7516611

RESUMEN

Wistar rat ventricular myocytes were isolated. Panaxadiol saponins 1500 micrograms.ml-1, panaxatriol saponins 300 micrograms.ml-1, verapamil 37.5 micrograms.ml-1, or BAY k 8644 5 mumol.L-1 were added into the bath solution separately. The single channel activities of L, T, and B type calcium channels were recorded before and after the administration, using voltage patch-clamp technique in cell-attached configuration. The calcium channel blockade effect of these 2 groups of ginsenosides was authenticated verified. The mechanism existed in the decrease in both the open time and the open-state probability of the calcium channel.


Asunto(s)
Canales de Calcio/efectos de los fármacos , Ginsenósidos , Miocardio/citología , Panax , Plantas Medicinales , Triterpenos/farmacología , Ácido 3-piridinacarboxílico, 1,4-dihidro-2,6-dimetil-5-nitro-4-(2-(trifluorometil)fenil)-, Éster Metílico/farmacología , Animales , Células Cultivadas , Ratas , Ratas Wistar , Verapamilo/farmacología
9.
Zhongguo Yao Li Xue Bao ; 13(2): 136-9, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1598830

RESUMEN

Addition of xanthine 0.42 mmol.L-1 and xanthine oxidase 5.3 nmol.L-1 (X-XO) to the culture medium increased the amplitude of ESR spectra of myocardial cells, demonstrating an increase in free radical contents; diminished the action potential parameters significantly and reduced the input impedances from 0.34 +/- 0.11 to 0.24 +/- 0.1 M omega, expressing a typical electrical appearance of membrane damage. Supplying Cu 62.5 ng.ml-1 and/or Se 173 ng.ml-1 to the medium brought all of the electric parameters and the free radical content of myocardial cells back to normal. The results indicate that both the two trace elements are able to scavenge free radicals, thus antagonizing X-XO, which induces damage to myocardial cells.


Asunto(s)
Cobre/farmacología , Miocardio/citología , Selenio/farmacología , Xantina Oxidasa/farmacología , Xantinas/farmacología , Potenciales de Acción/efectos de los fármacos , Animales , Células Cultivadas , Radicales Libres , Ratas , Ratas Endogámicas
10.
Chin Med J (Engl) ; 103(9): 735-42, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2123774

RESUMEN

Ventricular myocytes from neonatal Wistar rats were cultured with 80% Dulbecoo's modified Eagle medium and 20% fetal bovine serum. An appropriate amount of xanthine and xanthine oxidase was added to the culture medium to increase the content of free radicals in cardiac cells. Variation in action potential and input impedance of cardiac myocytes indicated the oxidative damage to the membrane. The ultrastructure of heart cells, characteristically the myofilaments and mitochondria, was damaged. Electron spin resonance measurement demonstrated that xanthine and xanthine oxidase elevated the free radical content, while selenium (Se) and manganese (Mn) reduced the free radicals in cultured heart cells. Supplementation of 0.173 microgram/ml Se and 0.1 microgram/ml Mn into the culture medium separately or simultaneously antagonized the damage induced by xanthine and xanthine oxidase. The possible mechanism might be the production of superoxide anion free radical leading to free radical damage to cardiac cells. Se and Mn might play a role as scavengers through glutathione peroxidase and superoxide dismutase respectively and thus protect cardiac cells from free radical damage.


Asunto(s)
Manganeso/farmacología , Miocardio/metabolismo , Selenio/farmacología , Potenciales de Acción/efectos de los fármacos , Animales , Células Cultivadas , Radicales Libres , Miocardio/citología , Ratas , Ratas Endogámicas , Xantina Oxidasa/metabolismo , Xantinas/metabolismo
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