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951.
María R. Castellanos Ortega Reyniel Cruz Aguado Lourdes Lorigados Pedr Karelys de la Cutara Bernal 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,753(2):253
Beta-nerve growth factor (β-NGF) is a trophic factor in the nervous system. We aimed to isolate and characterize this protein in view of its potential therapeutic use in neurodegenerative diseases. For purification a two-step ion-exchange procedure was followed. The characterization was performed using separation and immunological techniques, as well as a biological assay. These studies showed that the obtained protein consisted of a mixture of β-NGF molecules, intact at their NH2-terminal extreme, and molecules which have lost the NH2-terminal octapeptide and exhibit modifications increasing its hydrophobicity. All these molecular species were recognized immunologically and showed biological activity. 相似文献
952.
Enhancing the co-composting of olive mill wastes and sewage sludge by the addition of an industrial waste 总被引:4,自引:1,他引:3
In this work, the effect of incorporating an acidic ferrous sulphate waste (SF) over co-composting process of sewage sludge and olive mill solid wastes in a 1:2 v/v wet basis was investigated. The SF used was an industrial by-product of titanium oxide synthesis and its addition resulted in a chemical stabilisation of the wastes at low pH. The optimum dose of SF to enhance the composting of the studied biowastes was a 20% v/v (wet basis) and the best moment for the addition turned out to be whenever the composting piles had achieved the thermophilic range. The addition of SF over the composting process made possible a faster stabilisation, increasing the composting rate from 0.033 to 0.13 d(-1), and leading to a Fe and S rich compost. All composts obtained fulfilled the limits determined by current European and Spanish regulations and presented better characteristics for its use as soil amendment and organic fertilizer than the traditional composts without SF. The optimum dose of compost containing SF was determined through agronomic tests being its value about 18 Ton ha(-1). 相似文献
953.
Dols PP Folmer BJ Hamersma H Kuil CW Lucas H Ollero L Rewinkel JB Hermkens PH 《Bioorganic & medicinal chemistry letters》2008,18(4):1461-1467
We have developed a new class of progesterone receptor agonists having a tetracyclic dibenzo-oxazepine structure 1. In this paper, the synthesis and structure-activity relationships of this new class are described. This work led to the identification of potent progesterone agonists up to 1 nM activity. Substitution at positions 6, 7 and 1 has proven to be crucial for activity, indicating that probably these positions are involved in important interactions with the receptor. 相似文献
954.
Lourdes Montes 《L'Anthropologie》2008,112(2):168
After 30 years of research, we begin to perceive an incipient outline of the Upper Palaeolithic in the central Ebro Valley. The assembled data permit us to speak of human occupation on the Southern face of the Pyrenees, but also on the borders of the Iberian Mountains and of the Ebro basin. All these sites seem to mark the passageways from and to the neighbour territories, emphasizing the communication pathway role of the Iberian basin. 相似文献
955.
The aim of this work was to identify the initial binding sites to the bacterial membranes of the antimicrobial peptide alphas2-casein f(183-207) and also to acquire further insight into membrane permeabilization of this peptide. Furthermore, cell morphology was studied by transmission electron microscopy. In all the experiments, bovine LFcin was employed as a comparison. Results showed that initial binding sites of alphas2-casein f(183-207) peptide were lipoteichoic acid in Gram-positive bacteria and lipopolysaccharide in Gram-negative. The peptide was able to permeabilize the outer and inner membranes. Moreover, the alphas2-casein peptide f(183-207) generated pores in the outer membrane of Gram-negative bacteria and in the cell wall of Gram-positive bacteria. In the Gram-negative bacteria, f(183-207) originated cytoplasm condensation, and in the Gram-positive bacteria the cytoplasmic content leaked into the extracellular medium. Furthermore, the experiments of inner and outer membrane permeabilization performed with LFcin-B showed that this peptide also has the ability to permeabilize both the inner and outer membranes. 相似文献
956.
Eberlin A Grauffel C Oulad-Abdelghani M Robert F Torres-Padilla ME Lambrot R Spehner D Ponce-Perez L Würtz JM Stote RH Kimmins S Schultz P Dejaegere A Tora L 《Molecular and cellular biology》2008,28(5):1739-1754
Condensation of chromatin, mediated in part by posttranslational modifications of histones, is essential for cell division during mitosis. Histone H3 tails are dimethylated on lysine (Kme2) and become phosphorylated on serine (Sp) residues during mitosis. We have explored the possibility that these double modifications are involved in the establishment of H3 tail conformations during the cell cycle. Here we describe a specific chromatin conformation occurring at Kme2 and adjacently phosphorylated S of H3 tails upon formation of a hydrogen bond. This conformation appears exclusively between early prophase and early anaphase of the mitosis, when chromatin condensation is highest. Moreover, we observed that the conformed H3Kme2Sp tail is present at the diplotene and metaphase stages in spermatocytes and oocytes. Our data together with results obtained by cryoelectron microscopy suggest that the conformation of Kme2Sp-modified H3 tails changes during mitosis and meiosis. This is supported by biostructural modeling of a modified histone H3 tail bound by an antibody, indicating that Kme2Sp-modified H3 tails can adopt at least two different conformations. Thus, the H3K9me2S10p and the H3K27me2S28p sites are involved in the acquisition of specific chromatin conformations during chromatin condensation for cell division. 相似文献
957.
Erika Rodríguez-Lobato Lourdes Ramírez-Hobak Jorge E. Aquino-Matus Juan P. Ramírez-Hinojosa Víctor H. Lozano-Fernández Juan Xicohtencatl-Cortes Rigoberto Hernández-Castro Roberto Arenas 《Mycopathologia》2017,182(3-4):387-392
Mucormycosis is an invasive infection caused by opportunistic fungi. Rhizopus, Lichtheimia, Mucor and Rhizomucor are the most common isolated genera. Primary cutaneous mucormycosis is usually related to traumatic injuries, but immunocompromised cases are associated with underlying conditions such as diabetes mellitus and malignancies. The treatment of choice is surgical debridement and liposomal amphotericin B. We present a 40-year-old male with fever and a painful necrotic lesion on the middle back and history of poorly controlled diabetes mellitus. Rhizopus oryzae was isolated and identified using an internal transcribed spacer regions ITS1 and ITS2. An initial good response to treatment was observed; however, 7 days later a diabetic ketoacidosis due to poor adherence to treatment caused a lethal outcome. 相似文献
958.
Carlos?Antonio?Dávila-Figueroa Ma.?de?Lourdes de la Rosa-Carrillo Eugenio?Pérez-Molphe-BalchEmail author 《In vitro cellular & developmental biology. Plant》2005,41(4):540-545
Summary
In vitro propagation systems by means of areole activation were developed for Turbinicarpus laui, T. lophophoroides, T. pseudopectinatus, T. schmiedickeanus subsp. flaviflorus, T. schmiedickeanus subsp. klinkerianus, T. schmiedickeanus subsp. schmiedickeanus, T. subterraneus, and T. valdezianus. In vitro-germinated seedlings were used as a primary source of explants. Multiple shoot formation from areoles was achieved for three
explant types (apical, lateral, and transverse), cultured on Murashige and Skoog (MS) basal medium supplemented with 3% sucrose,
10 gl−1 agar and several treatments with cytokinins. Efficiencies were in the range from 7.8 shoots per explant in T. valdezianus up to 19.7 shoots per explant in T. pseudopectinatus, using the best treatment for each species and in a single proliferation cycle. Four of the studied species responded best
when 6-benzylaminopurine (3.3–8.8μM) was used, while 6-(γ,γ-dimethylallylamino)purine (19.7–24.6μM) showed better results in two species. The two remaining species showed no significant differences in their response to both
cytokinins. Regarding explant type, the best results were obtained with transverse cuts for five species, with apical explants
for one species, and the two remaining species showed no significant differences among the explants tested. Rooting of the
in vitro-generated shoots was achieved most efficiently on half- or full-strength MS basal medium. Rooting frequencies were in the
range from 54.2 to 94.2%, and the frequency of survival of the plants once transferred to soil was 91.6% on average. 相似文献
959.
Fortepiani LA Reckelhoff JF 《American journal of physiology. Regulatory, integrative and comparative physiology》2005,288(3):R733-R736
Treatment with tetrahydrobiopterin (BH(4)) reduces blood pressure in spontaneously hypertensive rats (SHR). In the present study, we tested the hypothesis that chronic BH(4) reduces blood pressure in male SHR by reducing testosterone biosynthesis mediated by increasing nitric oxide (NO). Male SHR, aged 17-18 wk, intact or castrated, were treated for 1 wk with BH(4) (20 mg.kg(-1).day(-1) ip). After 1 wk, mean arterial pressure (MAP), serum testosterone, and nitrate/nitrite excretion (NO(x)) were measured. MAP was significantly higher in intact males than castrated males (179 +/- 2 vs. 155 +/- 4 mmHg, P < 0.001). In intact males, BH(4) caused a 17% reduction in MAP (148 +/- 2 mmHg), had no effect on NO(x), and reduced serum testosterone by 85% (24.09 +/- 2.37 vs. 3.72 +/- 0.73 ng/dl; P < 0.001). In castrated males, BH(4) had no effect on MAP (152 +/- 5 mmHg) but increased NO(x) by 38%. When castrated males were supplemented with testosterone, MAP increased to the same level as in intact males (180 +/- 7 mmHg), and BH(4) had no effect on MAP (182 +/- 7 mmHg) or NO(x). NO has been shown to decrease testosterone biosynthesis. Chronic sodium nitrite (70 mg.kg(-1).day(-1) x 1 wk) decreased MAP in intact males (150 +/- 4 mmHg) but had no effect on serum testosterone (21.46 +/- 3.08 ng/dl). The data suggest that BH(4) reduces testosterone synthesis and thereby reduces MAP in male SHR, an androgen-dependent model of hypertension. The mechanism(s) by which BH(4) reduces serum testosterone levels are not clear, but the data do not support a role for NO as a mediator. 相似文献
960.
Yanes L Romero D Iliescu R Cucchiarelli VE Fortepiani LA Santacruz F Bell W Zhang H Reckelhoff JF 《American journal of physiology. Regulatory, integrative and comparative physiology》2005,288(4):R903-R908
The roles of nitric oxide (NO) and plasma renin activity (PRA) in the depressor response to chronic administration of Tempol in spontaneously hypertensive rats (SHR) are not clear. The present study was done to determine the effect of 2 wk of Tempol treatment on blood pressure [mean arterial pressure (MAP)], oxidative stress, and PRA in the presence or absence of chronic NO synthase inhibition. SHR were divided into four groups: control, Tempol (1 mmol/l) alone, nitro-L-arginine methyl ester (L-NAME, 4.5 mg x g(-1).day(-1)) alone, and Tempol + L-NAME or 2 wk. With Tempol, MAP decreased by 22%: 191 +/- 3 and 162 +/- 21 mmHg for control and Tempol, respectively (P < 0.05). L-NAME increased MAP by 16% (222 +/- 2 mmHg, P < 0.01), and L-NAME + Tempol abolished the depressor response to Tempol (215 +/- 3 mmHg, P < 0.01). PRA was not affected by Tempol but was increased slightly with L-NAME alone and 4.4-fold with L-NAME + Tempol. Urinary nitrate/nitrite increased with Tempol and decreased with L-NAME and L-NAME + Tempol. Tempol significantly reduced oxidative stress in the presence and absence of L-NAME. In conclusion, in SHR, Tempol administration for 2 wk reduces oxidative stress in the presence or absence of NO, but in the absence of NO, Tempol is unable to reduce MAP. Therefore, NO, but not changes in PRA, plays a major role in the blood pressure-lowering effects of Tempol. These data suggest that, in hypertensive individuals with endothelial damage and chronic NO deficiency, antioxidants may be able to reduce oxidative stress but not blood pressure. 相似文献