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111.
Yurixhi Maldonado–López Edelmira Linares–Mazari Robert Bye Guillermo Delgado Francisco J. Espinosa–García 《Economic botany》2008,62(2):161-170
Mexican Arnica Anti–Inflammatory Action: Plant Age Is Correlated with the Concentration of Anti–inflammatory Sesquiterpenes
in the Medicinal Plant
Heterotheca inuloides
Cass. (Asteraceae). Mexican árnica (Heterotheca inuloides Cass.) is a widely used anti–inflammatory medicinal plant in Mexican folk medicine. Although it has been suggested that plant
age, fertilization, and harvesting regime influence the concentration of secondary compounds affecting the therapeutic activity
of the plant, the effect of these variables on the concentration of the Mexican árnica anti–inflammatory compounds was not
known. We quantified anti–inflammatory sesquiterpenes (caryolan–1, 9β–diol, cadalen–15–oic acid, 7–hydroxycadalene, 4–hydroxy–2–isopropyl–4,
7–dimethyl–1[4H] naftalinone, 7–hydroxy–4αH–3, 4–dihydrocadalene, β–caryophyllene, and β–caryophyllene epoxide) in Mexican
árnica plants subjected to fertilization and successive harvests of flowering stems, conditions that mimic the cultivation
and harvesting for árnica in México. Fertilization and successive harvesting and their interaction had no significant effect
on the concentration of anti–inflammatory compounds. However, the concentrations of these compounds were 60% higher in flowering
stems from 15–month–old plants than in those from 4– or 8–month–old plants and was independent of the number of harvests and
fertilization regime applied. 相似文献
112.
Ortiz-Acevedo A Rigor RR Maldonado HM Cala PM 《American journal of physiology. Cell physiology》2008,295(5):C1316-C1325
Alteration in cell volume of vertebrates results in activation of volume-sensitive ion flux pathways. Fine control of the activity of these pathways enables cells to regulate volume following osmotic perturbation. Protein phosphorylation and dephosphorylation have been reported to play a crucial role in the control of volume-sensitive ion flux pathways. Exposing Amphiuma tridactylu red blood cells (RBCs) to phorbol esters in isotonic medium results in a simultaneous, dose-dependent activation of both Na(+)/H(+) and K(+)/H(+) exchangers. We tested the hypothesis that in Amphiuma RBCs, both shrinkage-induced Na(+)/H(+) exchange and swelling-induced K(+)/H(+) exchange are activated by phosphorylation-dependent reactions. To this end, we assessed the effect of calyculin A, a phosphatase inhibitor, on the activity of the aforementioned exchangers. We found that exposure of Amphiuma RBCs to calyculin-A in isotonic media results in simultaneous, 1-2 orders of magnitude increase in the activity of both K(+)/H(+) and Na(+)/H(+) exchangers. We also demonstrate that, in isotonic media, calyculin A-dependent increases in net Na(+) uptake and K(+) loss are a direct result of phosphatase inhibition and are not dependent on changes in cell volume. Whereas calyculin A exposure in the absence of volume changes results in stimulation of both the Na(+)/H(+) and K(+)/H(+) exchangers, superimposing cell swelling or shrinkage and calyculin A treatment results in selective activation of K(+)/H(+) or Na(+)/H(+) exchange, respectively. We conclude that kinase-dependent reactions are responsible for Na(+)/H(+) and K(+)/H(+) exchange activity, whereas undefined volume-dependent reactions confer specificity and coordinated control. 相似文献
113.
Manuel Maldonado 《Invertebrate Biology》2004,123(1):1-22
Abstract. It is widely accepted that multicellular animals (metazoans) constitute a monophyletic unit, deriving from ancestral choanoflagellate‐like protists that gave rise to simple choanocyte‐bearing metazoans. However, a re‐assessment of molecular and histological evidence on choanoflagellates, sponge choanocytes, and other metazoan cells reveals that the status of choanocytes as a fundamental cell type in metazoan evolution is unrealistic. Rather, choanocytes are specialized cells that develop from non‐collared ciliated cells during sponge embryogenesis. Although choanocytes of adult sponges have no obvious homologue among metazoans, larval cells transdifferentiating into choanocytes at metamorphosis do have such homologues. The evidence reviewed here also indicates that sponge larvae are architecturally closer than adult sponges to the remaining metazoans. This may mean that the basic multicellular organismal architecture from which diploblasts evolved, that is, the putative planktonic archimetazoan, was more similar to a modern poriferan larva lacking choanocytes than to an adult sponge. Alternatively, it may mean that other metazoans evolved from a neotenous larva of ancient sponges. Indeed, the Porifera possess some features of intriguing evolutionary significance: (1) widespread occurrence of internal fertilization and a notable diversity of gastrulation modes, (2) dispersal through architecturally complex lecithotrophic larvae, in which an ephemeral archenteron (in dispherula larvae) and multiciliated and syncytial cells (in trichimella larvae) occur, (3) acquisition of direct development by some groups, and (4) replacement of choanocyte‐based filter‐feeding by carnivory in some sponges. Together, these features strongly suggest that the Porifera may have a longer and more complicated evolutionary history than traditionally assumed, and also that the simple anatomy of modern adult sponges may have resulted from a secondary simplification. This makes the idea of a neotenous evolution less likely than that of a larva‐like choanocyte‐lacking archimetazoan. From this perspective, the view that choanoflagellates may be simplified sponge‐derived metazoans, rather than protists, emerges as a viable alternative hypothesis. This idea neither conflicts with the available evidence nor can be disproved by it, and must be specifically re‐examined by further approaches combining morphological and molecular information. Interestingly, several microbial lin°Cages lacking choanocyte‐like morphology, such as Corallochytrea, Cristidiscoidea, Ministeriida, and Mesomycetozoea, have recently been placed at the boundary between fungi and animals, becoming a promising source of information in addition to the choanoflagellates in the search for the unicellular origin of animal multicellularity. 相似文献
114.
Characterisation of micromonosporae from aquatic environments using molecular taxonomic methods 总被引:1,自引:1,他引:0
Large numbers of strains assigned to the genus Micromonospora on the basis of typical colonial and pigmentation features were isolated from diverse aquatic sediments using a standard selective isolation procedure. Two hundred and six isolates and eight representatives of the genus Micromonospora were assigned to 24 multimembered groups based on a numerical analysis of banding patterns generated using BOX and ERIC primers. Representatives of multimembered groups encompassing isolated micromonosporae were the subject of 16S rRNA gene sequencing analyses. Good congruence was found between the molecular fingerprinting and 16S rRNA sequence data indicating that the groups based upon the former are taxonomically meaningful. Nearly all of the isolates that were chosen for the 16S rRNA gene sequencing analyses showed that the ecosystems studied are a rich source of novel micromonosporae. These findings have implications for high throughput screening for novel micromonosporae as BOX and ERIC fingerprinting, which is rapid and reproducible, can be applied as a robust dereplication procedure to indicate which environmental isolates have been cultured previously. 相似文献
115.
Oral Administration of Lactobacillus Strains Isolated from Breast Milk as an Alternative for the Treatment of Infectious Mastitis during Lactation
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E. Jimnez L. Fernndez A. Maldonado R. Martín M. Olivares J. Xaus J. M. Rodríguez 《Applied microbiology》2008,74(15):4650-4655
In this study, 20 women with staphylococcal mastitis were randomly divided in two groups. Those in the probiotic group daily ingested 10 log10 CFU of Lactobacillus salivarius CECT5713 and the same quantity of Lactobacillus gasseri CECT5714 for 4 weeks, while those in the control one only ingested the excipient. Both lactobacillus strains were originally isolated from breast milk. On day 0, the mean staphylococcal counts in the probiotic and control groups were similar (4.74 and 4.81 log10 CFU/ml, respectively), but lactobacilli could not be detected. On day 30, the mean staphylococcal count in the probiotic group (2.96 log10 CFU/ml) was lower than that of the control group (4.79 log10 CFU/ml). L. salivarius CECT5713 and L. gasseri CECT5714 were isolated from the milk samples of 6 of the 10 women of the probiotic group. At day 14, no clinical signs of mastitis were observed in the women assigned to the probiotic group, but mastitis persisted throughout the study period in the control group women. In conclusion, L. salivarius CECT5713 and L. gasseri CECT5714 appear to be an efficient alternative for the treatment of lactational infectious mastitis during lactation. 相似文献
116.
J. M. Pozuelo M. M. Lucas C. de Lorenzo M. Fernández-Pascual S. Maldonado M. R. de Felipe 《Protoplasma》2001,218(1-2):104-111
Summary Immunolocalization of alkaloids in lupin seeds (Lupinus spp.) has been performed by cryofixation and conventional methods. Alkaloids were localized in the protein bodies of the cotyledon cells. Some immunogold particles in the walls of these cells were also observed. There were no differences in the sites of localization between the two mentioned methods. X-ray microanalysis of elements showed the presence of P, Mg, S, and K in the protein bodies of cotyledon cells in lupin seeds. The role of K+ in alkaloids transport is discussed. 相似文献
117.
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119.
A. I. Pilyavskii N. V. Bulgakova R. Maldonado B. P. Roques V. A. Yakhnitsa 《Neurophysiology》1999,31(5):316-322
Effects of a selective agonist of delta-opioid receptors, BUBU, and mixed inhibitors of enkephalin-degrading enzymes, RB-38A
and RB-101, on the background and evoked activity of periaqueductal gray (PAG) neurons were studied on slices of the rat midbrain.
The tested drugs could either activate or depress spontaneously active neurons, or exert no influence on these units, “Silent”
neurons generated no responses to application of the above compounds. In 80.5% of the studied neurons, 1 μM BUBU evoked depression,
while 6.5 μM RB-38A, 0.65 mM RB-38A, and 10 μM RB-101 depressed 68.8%, 73.7% and 68.8% of the neurons, respectively. Facilitatory
effects were induced by the above drugs in 5.0%, 5.9%, 15.8%, and 6.2% of the cells under study, respectively. The effects
of RB-38A and RB-101 differed from the BUBU-evoked responses in a shorter latency and rise time and a higher intensity. Repeated
application of RB-38A provided no significant changes in the duration and intensity of the inhibitory effects. Co-administration
of RB-38A and BUBU, or BUBU and RB-38A intensified suppression of the neuronal discharges without considerable changing their
duration. It is concluded that administration of inhibitors of enkephalin-degrading enzymes toin vitro midbrain preparations creates a pharmacologically effective level of endogenous enkephalins, which exerts specific inhibitory
influence on spontaneously active PAG neurons. The data are in agreement with the supposition on the existence of tonic release
of enkephalins in midbrain slice preparations. 相似文献