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1.
Molecular Biology Reports - Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers in humans, with less than 5% 5-year survival rate. PDAC is characterized by a small number of...  相似文献   
2.
Mesenchymal stem cells (MSCs) have a differentiation potential towards osteoblastic lineage when they are stimulated with soluble factors or specific biomaterials. This work presents a novel option for the delivery of MSCs from human amniotic membrane (AM-hMSCs) that employs bovine bone matrix Nukbone (NKB) as a scaffold. Thus, the application of MSCs in repair and tissue regeneration processes depends principally on the efficient implementation of the techniques for placing these cells in a host tissue. For this reason, the design of biomaterials and cellular scaffolds has gained importance in recent years because the topographical characteristics of the selected scaffold must ensure adhesion, proliferation and differentiation into the desired cell lineage in the microenvironment of the injured tissue. This option for the delivery of MSCs from human amniotic membrane (AM-hMSCs) employs bovine bone matrix as a cellular scaffold and is an efficient culture technique because the cells respond to the topographic characteristics of the bovine bone matrix Nukbone (NKB), i.e., spreading on the surface, macroporous covering and colonizing the depth of the biomaterial, after the cell isolation process. We present the procedure for isolating and culturing MSCs on a bovine matrix.  相似文献   
3.
A fast, reproducible, and efficient transformation procedure employing Agrobacterium rhizogenes was developed for Phaseolus vulgaris L. wild accessions, landraces, and cultivars and for three other species belonging to the genus Phaseolus: P. coccineus, P. lunatus, and P. acutifolius. Induced hairy roots are robust and grow quickly. The transformation frequency is between 75 and 90% based on the 35-S promoter-driven green fluorescent protein and beta-glucuronidase expression reporter constructs. When inoculated with Rhizobium tropici, transgenic roots induce normal determinate nodules that fix nitrogen as efficiently as inoculated standard roots. The A. rhizogenes-induced hairy root transformation in the genus Phaseolus sets the foundation for functional genomics programs focused on root physiology, root metabolism, and root-microbe interactions.  相似文献   
4.
Follicular atresia, a common process present in all mammals, involves apoptotic and autophagic cell death. However, the participation of paraptosis, a type of caspase‐independent cell death, during follicular atresia is unknown. This study found swollen endoplasmic reticulum in the granulosa cells of adult Wistar rats. Calnexin was used as a marker of the endoplasmic reticulum at the ultrastructural and optical levels. The cells with swelling of the endoplasmic reticulum were negative to the TUNEL assay and active caspase‐3 immunodetection, indicating that this swelling is not part of any apoptotic or autophagic process. Additionally, immunodetection of the CHOP protein was used as a marker of endoplasmic reticulum stress, and this confirmed the presence of the paraptosis process. These data suggest that paraptosis‐like cell death is associated with the death of granulosa cells during follicular atresia in adult Wistar rats.  相似文献   
5.

We hypothesized that cyclopoids, being predators, have a stronger allelopathic influence than calanoids on life-history variables of herbivorous rotifers. To test this hypothesis, we quantified the allelopathic effects of conditioned medium obtained separately from males and females of a calanoid (Arctodiaptomus dorsalis) and a cyclopoid (Mesocyclops longisetus) on the life table demography of the rotifer Brachionus havanaensis. The conditioned medium of the male and female A. dorsalis and male M. longisetus caused a significant reduction (14–18%) in the life expectancy at birth of B. havanaensis. Gross and net reproductive rates of rotifers reduced significantly on the conditioned medium of male or female A. dorsalis; however, the conditioned medium from either sex of M. longisetus had no significant effect on these variables. The population growth rate, r, varied from 0.53 to 0.64 d?1 depending on the treatment; the r was significantly lower when cultured on the conditioned medium from A. dorsalis (males or females) and female M. longisetus Contrary to our hypothesis, calanoid allelochemicals adversely affected the life history variables of rotifers more than those produced by the cyclopoids.

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6.
The aim of this study was to synthesize three different D-homoandrostadiene derivatives (24) and study their biological activity. We carried out in vivo and in vitro experiments using female cycling mice, which were synchronized for estrus with luteinizing hormone-releasing hormone (LHRH) and injected with the steroidal compounds. It was also determined the binding of these compounds to the progesterone receptors (PR). Since these steroids have a new D-homoandrostandienone skeleton in their molecular structure, it was of interest also to study their binding to the androgen receptors (AR).After LHRH treatment, the mice of the control group showed the presence of 14 ± 4 corpus lutea in the ovary whereas the animals treated with steroids 24, with RBAs of 100%, exhibited 11 ± 7, 12 ± 2, and 10 ± 4 respectively. As a result of this study, it is evident that these steroids did not inhibit the ovulation in these animals.The uterus of the control group, showed the typical progestational activity with an enlarged endometrial thickness with a secretory activity. However, the endometrium of the mice treated with steroids 24 did not show an enlargement of the endometrium and no secretory activity could be detected. This fact indicates that compounds 24 had antagonistic activity in this tissue.The overall data show that steroids 24 are antagonists of the PR. However, they do not bind to the AR. These results also demonstrate that 24 have an antiprogestational activity in vivo, but do not decrease the number of corpus lutea in the ovary of mice treated with LHRH.  相似文献   
7.
Argemone mexicana L. is a widely used plant in Mexican traditional medicine to treat inflammatory and nervous medical conditions. It has been subjected to several pharmacological and chemical studies in which acute anti-inflammatory activity is indicated. This work aimed at finding an extract and fraction with anti-inflammatory activity by means of 2-O-tetradecanoylphorbol-13-acetate (TPA)-induced auricular edema. Afterward, the extract and the fraction were tested on neuroinflammation caused by lipopolysaccharides (LPS). Treatments obtained from A. mexicana included the methanolic extract (AmMeOH), a fraction extracted with ethyl acetate (AmAcOEt), and four sub-fractions (AmF-1 to AmF-4), which were evaluated in auricular edema with the TPA assay. Both treatments with the most significant inhibitory effect were employed to test these in the LPS neuroinflammation model. AmAcOEt and AmF-3 induced a higher inhibition of edema (%), and both diminished ear inflammation when viewed under a microscope. These treatments also raised an increase in spleen, but not in brain of mice with neuroinflammation. They were able to decrease the concentration of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) in both organs. Furthermore, the accumulation of amyloid-β (Aβ) in hippocampus was not visible. AmF-3 contains the flavonoids isoquercetin, luteolin, and rutin, the former being the most concentrated.  相似文献   
8.
Purinergic Signalling - We previously reported that the activation of histamine H3 receptors (H3Rs) selectively counteracts the facilitatory action of adenosine A2A receptors (A2ARs) on GABA...  相似文献   
9.
Odontogenesis is extensively studied in animal models but less understood in human. In early amelogenesis, amelogenin constitutes 90% of enamel organic matrix, which is degraded by enamelysin and replaced by hydroxyapatite crystals. Here, amelogenin and enamelysin distribution changes during amelogenesis were shown by co-localization experiments by confocal microscopy. Early bell stage showed more amelogenin labeling than enamelysin, as free immune-reactive granular patches towards basal membrane between ameloblast and odontoblast. Increased amelogenin expression and secretion towards extracellular matrix formation region was found. Enamelysin distribution was perinuclear in early bell stage. During late bell stage, a decreasing amelogenin labeling in contrast with enamelysin increasing along the cells was found, suggesting specific temporal amelogenin degradation. Enamelysin was located initially around nuclei and later was found in all the ameloblast and stellate reticulum cytoplasm. Amelogenin was observed inside ameloblast, stellate reticulum, and intermediate stratum cells in the enamel as well as in the newly formed dentin extracellular matrix. In contrast, in dentin more amelogenin than enamelysin was found located close to the periphery.  相似文献   
10.
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