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51.
Vargas-Ponce Ofelia Pérez-Álvarez Luis F. Zamora-Tavares Pilar Rodríguez Aaron 《Plant Molecular Biology Reporter》2011,29(3):733-738
Mexico is the center of diversity of the husk tomato (Physalis L., Solanaceae), which includes a number of commercially important edible and ornamental species. Taxonomic identification
is presently based on morphological characteristics, but the presence of high inter- and intraspecific morphological variation
makes this task difficult. Six ISSR primers were used on eight Mexican species of Physalis to determine their utility for interspecific taxonomic discrimination and to assess their potential for inferring interspecific
relationships. The six ISSR primers amplified 101 bands, with 100% polymorphism across samples. The number of bands per primer
varied from 10 to 21. All primers produced different fingerprint profiles for each species, confirming the ISSR value in taxonomic
discrimination. Discrimination values based on Simpson’s diversity index varied from 0.48 to 0.58. Genetic interspecific similarity
values ranged from 0.20 to 0.57, and intraspecific similarity values were highest for Physalis angulata (0.71), followed by Physalis philadelphica (0.63) and Physalis lagascae (0.55). The UPGMA analysis grouped accessions of the same species together and clustered together Physalis species of similar morphological traits. Thus, ISSR markers are useful in estimating genetic relationships in Physalis. 相似文献
52.
de Castro UG de Sousa GG Machado Rdo P Isoldi MC Silva ME Nadu AP Sousa LE Santos RA Campagnole-Santos MJ Alzamora AC 《Nitric oxide》2012,26(2):118-125
Hypertension is associated to an increase in central oxidative stress and an attenuation of the baroreflex control of arterial pressure. The present study evaluated the effect of alterations in the levels of nitric oxide (NO) and superoxide anion in the caudal ventrolateral medulla (CVLM), a key area of the brainstem for the baroreflex control of arterial pressure, in renovascular hypertensive rats (2K1C). Baseline mean arterial pressure (MAP), heart rate (HR), and reflex bradycardia were evaluated 30 days after renal artery occlusion in anesthetized (urethane, 1.2 g/kg, i.p.) 2K1C or normotensive (SHAM) rats. The MAP, HR, and baroreflex control of HR were evaluated before and after CVLM microinjections of the non-selective NOS inhibitor L-NAME (10 nmol), the NO precursor L-ARG (50 nmol), or the antioxidant ascorbic acid, Vit C (10 nmol). In both 2K1C and SHAM animals, CVLM microinjection of L-NAME produced a decrease in MAP, whereas L-ARG induced a significant increase in MAP. However, microinjection of Vit C into the CVLM produced a decrease in MAP and HR only in 2K1C and not in SHAM rats. Cardiovascular effects produced by microinjection of l-ARG into the CVLM were abolished by prior microinjection of L-NAME in the CVLM of 2K1C and SHAM rats. Microinjection of L-NAME into the CVLM increased the sensitivity of reflex bradycardia in 2K1C animals. In contrast, the CVLM microinjection of L-ARG reduced reflex bradycardia only in SHAM rats. Vit C in the CVLM did not change reflex bradycardia in either 2K1C or in SHAM rats. These results suggest that increased oxidative stress in the CVLM during hypertension contributes to the reduced baroreflex sensitivity and to maintain hypertension in the 2K1C model. 相似文献
53.
The characterization and prediction of the structures of metal silicon clusters is important for nanotechnology research because these clusters can be used as building blocks for nano devices, integrated circuits and solar cells. Several authors have postulated that there is a transition between exo to endo absorption of Cu in Si(n) clusters and showed that for n larger than 9 it is possible to find endohedral clusters. Unfortunately, no global searchers have confirmed this observation, which is based on local optimizations of plausible structures. Here we use parallel Genetic Algorithms (GA), as implemented in our MGAC software, directly coupled with DFT energy calculations to show that the global search of CuSi(n) cluster structures does not find endohedral clusters for n < 8 but finds them for n ≥ 10. 相似文献
54.
Aguilera AA Díaz GH Barcelata ML Guerrero OA Ros RM 《The Journal of nutritional biochemistry》2004,15(6):350-357
Dietary fish oil rich in (n-3) fatty acids plays an important role in reducing abnormalities associated with the metabolic syndrome and mortality from coronary heart disease. We investigated the effects of dietary fish oil on the metabolic syndrome in a high-sucrose-fed rat model. The model was achieved by the administration of 30% sucrose in drinking water in male Wistar rats during 21 weeks. After the metabolic syndrome rat model was established, fish oil was administered during 6 weeks. The metabolic syndrome rats showed significant increases in body weight, systolic blood pressure, serum insulin, total lipids, triacylglycerols, cholesterol, free fatty acids, LDL, total proteins, albumin, and serum tumor necrosis factor-alpha (TNF-alpha). They also presented abdominal and epididymal fat accumulation and fatty liver. After fish oil diet administration, metabolic syndrome rats had a significant reduction in blood pressure, serum insulin, triacylglycerols, cholesterol, free fatty acids, and total lipids, but no change was observed in TNF-alpha concentration or fat accumulation. In conclusion, fish oil reversed the alterations on metabolic parameters and blood pressure exerted by sucrose administration, although it had no effect on TNF-alpha production and adiposity. This confirms the theory that the molecular etiology of the metabolic syndrome is multifactorial, as is the effect of n-3 polyunsaturated fatty acids (PUFAs) upon it, having complex and multifaceted actions. 相似文献
55.
56.
Ofelia Vargas-Ponce Daniel Zizumbo-Villarreal Patricia Colunga-García Marin 《Economic botany》2007,61(4):362-375
Extensive monovarietal cultivation of Age tequilana Weber var. azul is threatening the diversity of the germplasm used in traditional Agave spirits production in west-central Mexico. To promote the preservation, use, and management of this germplasm, an ethnobotanical and morphological study was done in the center and south of the state of Jalisco, Mexico. The richness, distribution, and morphological variation of wild and cultivated Agave populations were characterized, and producers’ roles in germplasm maintenance and diversification were analyzed. Results indicated that: 1) A. angustifolia and A. rhodacantha are the primary gene pools used for selection; 2) Traditional landraces are differentiated morphological entities; and 3) In situ maintenance and increase of Agave germplasm diversity are the result of constant selection of wild germplasm, producer management of populations in the wild-domesticated gradient, and preservation of old landraces. Preservation of Agave germplasm diversity in west-central Mexico requires increased cultivation and valuation of traditional landraces. 相似文献
57.
Arbyn M Primic-Zakelj M Raifu AO Grce M Paraskevaidis E Diakomanolis E Kesić V Nicula FA Suteu O von Karsa L 《Collegium antropologicum》2007,31(Z2):7-10
The situation of cervical cancer prevention in South-East Europe is hardly documented, in spite of the fact that it encloses the most affected countries of Europe. We estimated the number of cases of cervical cancer, the number of deaths from this malignancy and the corresponding rates for 11 countries located in South-East Europe, in the period 2002-2004. Each year, approximately 9,000 women develop cervical cancer and about 4,600 die from the disease in this subcontinent. The most affected country is Romania with almost 3,500 cases and more than 2,000 deaths per year High world-age standardised mortality rates (> 7.5 [expressed per 100,000 women-years]) are observed in 7 countries: FYROM (7.6), Moldova (7.8), Bulgaria (8.0), Bosnia & Herzegovina (8.0), Albania (9.8), Serbia & Montenegro (10.1) and Romania (13.0). A matter of concern is the increasing mortality rate, in younger women, in the countries with the highest burden of cervical cancer. Thus, appropriate cervical cancer prevention programmes should be set up without delay in this part of Europe. 相似文献
58.
Laura Raquel Orozco-Meléndez Ofelia Adriana Hernández-Rodríguez Oscar Cruz-Álvarez Loreto Robles-Hernández Graciela Dolores Ávila-Quezada Esteban Sánchez Chavez Damián Aarón Porras-Flores Dámaris Leopoldina Ojeda-Barrios 《Phyton》2022,91(1):1-12
There are documentary records referring to paclobutrazol (PBZ) as a growth bioregulator that inhibits the gibberellin synthesis and its application increases yields in fruit and vegetable crop productions. Its agronomic management includes it as an emerging technology to reduce vigour, promote flower induction and flower development in fruit trees with increased economic returns. Its use is banned in some countries because of concerns about residues that can cause harmful effects on the environment. Therefore, the aim of this article was to collect, analyse and summarise relevant information on the use of PBZ in fruit tree production and its possible risks to the environment. The results obtained indicated that the application of PBZ can be effective in solving some problems related to flowering if it is applied in the right amount and at the right time. However, it is necessary to elucidate the physiological processes with which it is associated and its response to be taken into account to increase yield. PBZ is currently used in fruit trees such as mango, lime, apple and guava, increasing their productivity. However, some studies have shown its residual effect on the environment. Therefore, PBZ is a viable strategy, because it presents a series of advantages in the production of fruit trees. However, it is vital to generate protocols that seek its regulation with a rational and sustainable approach. 相似文献
59.
Alejandro Martorell-Riera Marc Segarra-Mondejar Manuel Reina Ofelia M Martínez-Estrada Francesc X Soriano 《Cell cycle (Georgetown, Tex.)》2015,14(9):1365-1369
Mitochondria morphology constantly changes through fission and fusion processes that regulate mitochondrial function, and it therefore plays a prominent role in cellular homeostasis. Cell death progression is associated with mitochondrial fission. Fission is mediated by the mainly cytoplasmic Drp1, which is activated by different post-translational modifications and recruited to mitochondria to perform its function. Our research and other studies have shown that in the early moments of excitotoxic insult Drp1 must be nitrosylated to mediate mitochondrial fragmentation in neurons. Nonetheless, mitochondrial fission is a multistep process in which filamentous actin assembly/disassembly and myosin-mediated mitochondrial constriction play prominent roles. Here we establish that in addition to nitric oxide production, excitotoxicity-induced mitochondrial fragmentation also requires activation of the actomyosin regulator ROCK. Although ROCK1 has been shown to phosphorylate and activate Drp1, experiments using phosphor-mutant forms of Drp1 in primary cortical neurons indicate that in excitotoxic conditions, ROCK does not act directly on Drp1 to mediate fission, but may act on the actomyosin complex. Thus, these data indicate that a wider range of signaling pathways than those that target Drp1 are amenable to be inhibited to prevent mitochondrial fragmentation as therapeutic option. 相似文献
60.