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931.
Biopharmaceuticals make up a significant proportion of medicinal products used for the treatment of diseases such as cancer, arthritis, cardiac dysfunctions and AIDS. Access to therapies based on the use of these products has been limited as a result of the high marketing costs. Cuba has a biopharmaceutical industry with great potential for innovation, capable of developing new products and to produce others, like the biosimilars destined to fulfill the needs of its National Health System. The Center for State Control on the Quality of Drugs (CECMED) the Cuban NRA, is facing the challenge of regulating the approval of biosimilar products manufactured locally. Consequently, CECMED has issued a position paper establishing the basic principles for regulation of these products and a specific guideline on this was elaborated.  相似文献   
932.
Profilin, a multigene family involved in actin dynamics, is a multiple partners-interacting protein, as regard of the presence of at least of three binding domains encompassing actin, phosphoinositide lipids, and poly-L-proline interacting patches. In addition, pollen profilins are important allergens in several species like Olea europaea L. (Ole e 2), Betula pendula (Bet v 2), Phleum pratense (Phl p 12), Zea mays (Zea m 12) and Corylus avellana (Cor a 2). In spite of the biological and clinical importance of these molecules, variability in pollen profilin sequences has been poorly pointed out up until now. In this work, a relatively high number of pollen profilin sequences have been cloned, with the aim of carrying out an extensive characterization of their polymorphism among 24 olive cultivars and the above mentioned plant species. Our results indicate a high level of variability in the sequences analyzed. Quantitative intra-specific/varietal polymorphism was higher in comparison to inter-specific/cultivars comparisons. Multi-optional posttranslational modifications, e.g. phosphorylation sites, physicochemical properties, and partners-interacting functional residues have been shown to be affected by profilin polymorphism. As a result of this variability, profilins yielded a clear taxonomic separation between the five plant species. Profilin family multifunctionality might be inferred by natural variation through profilin isovariants generated among olive germplasm, as a result of polymorphism. The high variability might result in both differential profilin properties and differences in the regulation of the interaction with natural partners, affecting the mechanisms underlying the transmission of signals throughout signaling pathways in response to different stress environments. Moreover, elucidating the effect of profilin polymorphism in adaptive responses like actin dynamics, and cellular behavior, represents an exciting research goal for the future.  相似文献   
933.
934.
Physiological relevance of dietary melanoidins   总被引:1,自引:0,他引:1  
Morales FJ  Somoza V  Fogliano V 《Amino acids》2012,42(4):1097-1109
Melanoidins are the final products of the Maillard reaction. The main dietary sources of melanoidins are coffee, bread crust, bakery products, black beer and cocoa. Although the chemical structures of melanoidins are widely unknown, data from gravimetric techniques allow to roughly estimate a daily intake in the order of 10 g with a Western diet. Melanoidins contribute to the sensorial properties, modulating texture and flavour of foods. Growing evidence also suggests that melanoidins have health beneficial properties, such as chemopreventive, antioxidant and antimicrobial activities, and the ability to chelate different minerals. In the gastrointestinal tract, melanoidins behave not only as antioxidants, but also as dietary fibre by promoting the growth of bifidobacteria. This array of biological activities suggests the need for analytical techniques to identify the melanoidin structures and to control their formation during thermal food processing.  相似文献   
935.
936.
The present study is focused on the etherification of biodiesel-derived glycerol with anhydrous ethanol over arenesulfonic acid-functionalized mesostructured silicas to produce ethyl ethers of glycerol that can be used as gasoline or diesel fuel biocomponents. Within the studied range, the best conditions to maximize glycerol conversion and yield towards ethyl-glycerols are: T = 200 °C, ethanol/glycerol molar ratio = 15/1, and catalyst loading = 19 wt%. Under these reaction conditions, 74% glycerol conversion and 42% yield to ethyl ethers have been achieved after 4 h of reaction but with a significant presence of glycerol by-products. In contrast, lower reaction temperatures (T = 160 °C) and moderate catalyst loading (14 wt%) in presence of a high ethanol concentration (ethanol/glycerol molar ratio = 15/1) are necessary to avoid the formation of glycerol by-products and maximize ethyl-glycerols selectivity. Interestingly, a close catalytic performance to that achieved using high purity glycerol has been obtained with low-grade water-containing glycerol.  相似文献   
937.
The canonical two neuron model of opioid reward posits that mu opioid receptor (MOR) activation produces reward by disinhibiting midbrain ventral tegmental area (VTA) dopamine neurons through inhibition of local GABAergic interneurons. Although indirect evidence supports the neural circuit postulated by this model, its validity has been called into question by growing evidence for VTA neuronal heterogeneity and the recent demonstration that MOR agonists inhibit GABAergic terminals in the VTA arising from extrinsic neurons. In addition, VTA MOR reward can be dopamine-independent. To directly test the assumption that MOR activation directly inhibits local GABAergic neurons, we investigated the properties of rat VTA GABA neurons directly identified with either immunocytochemistry for GABA or GAD65/67, or in situ hybridization for GAD65/67 mRNA. Utilizing co-labeling with an antibody for the neural marker NeuN and in situ hybridization against GAD65/67, we found that 23±3% of VTA neurons are GAD65/67(+). In contrast to the assumptions of the two neuron model, VTA GABAergic neurons are heterogeneous, both physiologically and pharmacologically. Importantly, only 7/13 confirmed VTA GABA neurons were inhibited by the MOR selective agonist DAMGO. Interestingly, all confirmed VTA GABA neurons were insensitive to the GABA(B) receptor agonist baclofen (0/6 inhibited), while all confirmed dopamine neurons were inhibited (19/19). The heterogeneity of opioid responses we found in VTA GABAergic neurons, and the fact that GABA terminals arising from neurons outside the VTA are inhibited by MOR agonists, make further studies essential to determine the local circuit mechanisms underlying VTA MOR reward.  相似文献   
938.
Potassium channels play important physiological roles in human syncytiotrophoblasts (hSTBs) from placenta, an epithelium responsible for maternal–fetal exchange. Basal and apical plasma membranes differ in their lipid and protein composition, and the latter contains cholesterol-enriched microdomains. In placental tissue, the specific localization of potassium channels is unknown. Previously, we described two isolated subdomains from the apical membrane (MVM and LMVM) and their respective microdomains (lipid rafts). Here, we report on the distribution of Kir2.1, Kv2.1, TASK-1, and TREK-1 in hSTB membranes and the lipid rafts that segregate them. Immunoblotting experiments showed that these channels are present mainly in the apical membrane from healthy hSTBs. Apical expression versus basal membrane was 84 and 16% for Kir2.1 and Kv2.1, 60 and 30% for TREK-1, and 74 and 26% for TASK-1. Interestingly, Kv2.1 showed differences between apical membrane subdomains: 26 ± 8% was located in the LMVM and 59 ± 9% in MVM. In pathological placentas, the expression distribution changed in the basal membrane: preeclampsia shifted to 50% and intrauterine growth restriction to 42% for TASK-1 and both pathologies increased to 25% for Kir2.1 and Kv2.1, Kir2.1 appeared to be associated with rafts that were sensitive to cholesterol depletion in healthy, but not in pathological, placentas. Kv2.1 and TREK-1 emerged in the nonraft fractions. The precise membrane localization of ion channels in hSTB membranes is necessary to understand the physiological events.  相似文献   
939.
940.
Two new species of Lachemilla (Rosaceae) are described and illustrated. Lachemilla jaramilloi Romoleroux &Morales‐Briones from Ecuador is characterized by its decumbent habit, villous‐hirsute pubescence, long basal petiole, and deeply tri‐parted leaf blades. The flowers are sessile to subsessile and subtended by episepals, and the hypanthia elongated and glabrescent. Lachemilla talamanquensis Romoleroux & Morales‐Briones from Costa Rica is distinguished by its sericeous‐villous, ascending branches, sub‐sessile distal leaves, tri‐lobed leaf blades, forming whorls with the stipule. The flowers are solitary or arranged in few‐flowered inflorescences, with big, dark, villous hypanthia, containing several achenes.  相似文献   
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