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121.
Studying in detail different histomorphological and pathological findings in placental stem and terminal villi of appropriate for gestational age (AGA) and idiopathic intrauterine growth restricted (IUGR) fetuses, then analyzing their correlation to the neonatal birth weight and to the some morphological features of the placenta. Fifty full-term human placentae of idiopathic IUGR and 25 of AGA pregnancies were processed for haematoxylin and eosin staining and evaluated by light microscope aided with Image Analyzer. The mean number of stem villous arteries, and the mean number of terminal villous capillaries per field are significantly lower in idiopathic IUGR group (4.63 ± 0.46, 47.09 ± 4.44, respectively) than in AGA group (12.36 ± 0.61, 73.35 ± 5.13, respectively) (p = 0.001). Both AGA and idiopathic IUGR placentae share the presence of many pathological features: (1) narrowing of stem villous arteries appears in 38 (76 %) of IUGR cases and in 9 (36 %) of AGA cases with significant difference between groups (p = 0.001); (2) cellular infiltration (villitis) of the stem villi is significantly higher in IUGR cases [24 (48 %)] than in AGA cases [2 (8 %)] (p = 0.001). The study shows significant correlation between the birth weight and different pathologic features in the stem villi as arterial number (r = 0.494; p = 0.000), arterial narrowing (r = 0.283, p = 0.004), degenerative changes (r = 0.331, p = 0.001) and villitis (r = 0.275, p = 0.005). There is also significant correlation between neonatal birth weight and terminal villous capillary number (r = 0.281, p = 0.001) but no significant correlation is found between the birth weight and terminal villous fibrotic changes (r = -0.098, p = 0.318). Histomorphological and pathological changes in the stem villi could explore the cause of idiopathic IUGR. Stem villous arterial number, arterial narrowing, degeneration and villitis could be underlying mechanisms. Further researches on the hormonal and cytokine level should be undertaken to demonstrate the precipitating factors of these changes and the possible preventing measures.  相似文献   
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The pathophysiology of Type 1 diabetes (T1D) appears largely related to an innate defect in the immune system culminating in a loss of self tolerance and destruction of the insulin producing β-cells. Currently, there is no definitive cure for diabetes. Insulin injection does not mimic the precise regulation of β-cells on glucose homeostasis, leading long term to the development of complications. Other therapeutic approaches therefore, are necessary and cell therapy is thought to be a possible approach. In this sense, mesenchymal stem cells (MSCs) can offer a promising possibility that deserves to be explored. MSCs are multipotent non-hematopoietic progenitor cells. Their therapeutic potentials have recently been brought into the spotlights of many fields of research. Although the regenerative capabilities of MSCs have been a driving force to initiate studies testing their therapeutic effectiveness, their immunomodulatory properties have been equally exciting. MSCs possess specific immunomodulatory properties that would appear capable of disabling immune dysregulation that leads to β-cell destruction in T1D. Furthermore, MSCs can be sequentially cultured in specially defined conditions and their differentiation extends toward the β-cell phenotype and the formation of insulin producing cells (IPCs). To date, the role of MSCs in T1D remains completely unexplored. We herein summarize multiple strategies that have been proposed and tested for its potential therapeutic benefit for T1D.  相似文献   
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The essential oils isolated from three organs, i.e., fruits, stems and leaves, and flowers, of the endemic North African plant Scabiosa arenaria Forssk. were screened for their chemical composition, as well as their possible antibacterial, anticandidal, and antifungal properties. According to the GC-FID and GC/MS analyses, 61 (99.26% of the total oil composition), 79 (98.43%), and 51 compounds (99.9%) were identified in the three oils, respectively. While α-thujone (34.39%), camphor (17.48%), and β-thujone (15.29%) constituted the major compounds of the fruit oil, chrysanthenone (23.43%), together with camphor (12.98%) and α-thujone (10.7%), were the main constituents of the stem and leaf oil. In the case of the flower oil, also chrysanthenone (38.52%), camphor (11.75%), and α-thujone (9.5%) were identified as the major compounds. Furthermore, the isolated oils were tested against 16 Gram-positive and Gram-negative bacteria, four Candida species, and nine phytopathogenic fungal strains. It was found that the oils exhibited interesting antibacterial and anticandidal activities, comparable to those of thymol, which was used as positive control, but no activity against the phytopathogenic fungal strains was observed.  相似文献   
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Miltefosine (MFS) is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD). This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs) as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%), good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs, allowing targeting via the oral route. From a clinical point of view, data suggest MFS-LNCs as a potential single dose oral nanomedicine for enhanced therapy of schistosomiasis mansoni and possibly other diseases.  相似文献   
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Carbonic anhydrases (CAs) play fundamental roles in several physiological events, and emerging evidence points at their involvement in an array of disorders, including cancer. The expression of CAs in the different cells of teeth is unknown, let alone their expression patterns during odontogenesis. As a first step towards understanding the role of CAs during odontogenesis, we used immunohistochemistry, histochemistry and in situ hybridization to reveal hitherto unknown dynamic distribution patterns of eight CAs in mice. The most salient findings include expression of CAII/Car2 not only in maturation-stage ameloblasts (MA) but also in the papillary layer, dental papilla mesenchyme, odontoblasts and the epithelial rests of Malassez. We uncovered that the latter form lace-like networks around incisors; hitherto these have been known to occur only in molars. All CAs studied were produced by MA, however CAIV, CAIX and CARPXI proteins were distinctly enriched in the ruffled membrane of the ruffled MA but exhibited a homogeneous distribution in smooth-ended MA. While CAIV, CAVI/Car6, CAIX, CARPXI and CAXIV were produced by all odontoblasts, CAIII distribution displayed a striking asymmetry, in that it was virtually confined to odontoblasts in the root of molars and root analog of incisors. Remarkably, from initiation until near completion of odontogenesis and in several other tissues, CAXIII localized mainly in intracellular punctae/vesicles that we show to overlap with LAMP-1- and LAMP-2-positive vesicles, suggesting that CAXIII localizes within lysosomes. We showed that expression of CAs in developing teeth is not confined to cells involved in biomineralization, pointing at their participation in other biological events. Finally, we uncovered novel sites of CA expression, including the developing brain and eye, the olfactory epithelium, melanoblasts, tongue, notochord, nucleus pulposus and sebaceous glands. Our study provides important information for future single or multiple gene targeting strategies aiming at deciphering the function of CAs during odontogenesis.  相似文献   
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