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11.
We present a study on the synthesis, characterization and application of sodium carbonate tag silica-coated nano-Fe3O4 (Fe3O4@SiO2@(CH2)3OCO2Na) as a novel and efficient heterogeneous basic catalyst. The described catalyst was fully characterized via FT-IR, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), and field emission scanning electron microscopy (FE-SEM). The reported novel magnetic nanocatalyst presents an excellent activity and catalytic performance for the synthesis of a novel series of pyranocoumarins through the reaction of dialkyl acetylenedicarboxylates and 5,7-dihydroxy coumarin derivatives at 100 °C under solvent-free conditions.

We present a study on the synthesis, characterization and application of sodium carbonate tag silica-coated nano-Fe3O4 (Fe3O4@SiO2@(CH2)3OCO2Na) as a novel and efficient heterogeneous basic catalyst.  相似文献   
12.
Chronic allograft nephropathy is characterized by chronic inflammation and fibrosis. Because retinoids exhibit anti-proliferative, anti-inflammatory, and anti-fibrotic functions, the effects of low and high doses of 13-cis-retinoic acid (13cRA) were studied in a chronic Fisher344-->Lewis transplantation model. In 13cRA animals, independent of dose (2 or 20 mg/kg body weight/day) and start (0 or 14 days after transplantation) of 13cRA administration, serum creatinine was significantly lower and chronic rejection damage was dramatically reduced, including subendothelial fibrosis of preglomerular vessels and chronic tubulointerstitial damage. The number of infiltrating mononuclear cells and their proliferative activity were significantly diminished. The mRNA expression of chemokines (MCP-1/CCL2, MIP-1alpha/CCL3, IP-10/CXCL10, RANTES/CCL5) and proteins associated with fibrosis (plasminogen activator inhibitor-1, transforming growth factor-beta1, and collagens I and III) were strikingly lower in treated allografts. In vitro, activated peritoneal macrophages of 13cRA-treated rats showed a pronounced decrease in protein secretion of inflammatory cytokines (eg, tumor necrosis factor-alpha, interleukin-6). The suppression of the proinflammatory chemokine RANTES/CCL5 x 13cRA in fibroblasts could be mapped to a promoter module comprising IRF-1 and nuclear factor-kappaB binding elements, but direct binding of retinoid receptors to promoter elements could be excluded. In summary, 13cRA acted as a potent immunosuppressive and anti-fibrotic agent able to prevent and inhibit progression of chronic allograft nephropathy.  相似文献   
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Inflammatory infiltrates can modify (lipo)proteins via hypochlorous acid/hypochlorite (HOCl/OCl(-)) an oxidant formed by the myeloperoxidase-H(2)O(2)-halide system. These oxidatively modified proteins emerge in tubuli in some proteinuric and interstitial diseases. Human proximal tubular cells (HK-2) were used to confirm the hypothesis of detrimental and differential impact of HOCl-modified low density lipoprotein (HOCl-LDL), an in vivo occurring lipoprotein modification exerting proatherogenic and proinflammatory capacity. HOCl-LDL showed dose-dependent antiproliferative effects in HK-2 cells. Small dedicated cDNA macroarrays were used to identify differentially regulated genes. A rapid increase in the expression of genes involved in reactive oxygen species metabolism and cell stress, eg, heme oxygenase-1, thioredoxin reductase, cytochrome b5 reductase, Gadd 153, amino acid transporter E16, and HSP70 was found after HOCl-LDL treatment of HK-2 cells. In parallel, genes involved in tissue remodeling and inflammation eg, CTGF, VCAM-1, IL-1beta, MMP7, and VEGF were up-regulated. Quantitative RT-PCR verified differential expression of a subset of these genes in microdissected tubulointerstitia from patients with acute tubular damage, progressive proteinuric renal disease, and membranous glomerulonephritis (with declining renal function), but not in stable patients with proteinuria caused by minimal change disease. The demonstration of selective up-regulation of a subgroup of genes if proteinuria is accompanied by the presence of HOCl-modified (lipo)proteins support the potential pathophysiological role of the myeloperoxidase-H(2)O(2)-halide system and HOCl-LDL in renal disease.  相似文献   
14.
This study was conducted to measure selected hematological parameters in goats naturally infected with Anaplasma ovis. In this study 193 blood samples were collected from adult and young goats in north (Gonbad) and northeast (Mashhad) of Iran. Out of the 193 blood samples, 123 samples were positive (infected group) and 70 samples were negative (uninfected group) for A. ovis by polymerase chain reaction. Hematological analysis was carried out on 47 samples from the infected group and 37 samples from the uninfected group. Hematological analysis indicated significant decreases (P?<?0.01) in RBC counts, HCT values, and hemoglobin concentrations in the A. ovis-infected group of goats compared to the uninfected group (P?<?0.01). The mean corpuscular volume, mean corpuscular hemoglobin, WBC counts, lymphocytes, eosinophils, and monocytes in the infected group were lower but neutrophils were higher than in the uninfected group. These differences were not statistically significant (P?>?0.05). The result from this study revealed that A. ovis infection in goats is associated with marked changes in hematological parameters.  相似文献   
15.
This prospective study aimed to compare the value of fine needle aspiration (FNA) cytology (FNAC) and flow cytometric immunophenotyping (FCI) with histopatopathology (HP) in the diagnosis and classification of non-Hodgkin lymphoma (NHL). Twenty-nine excised lymph nodes suspected of NHL were evaluated using FNAC, FCI, and HP. Specimens were divided into two equal parts; one for HP and the other for FNAC and FCI. Results were compared in terms of diagnosis (malignant, benign or reactive, and metastatic) and NHL class. With combined FNAC/FCI, 11 (37.9%) cases were diagnosed as NHL, 11 cases (37.9%) as reactive lymph node, six cases (20.6%) as Hodgkin's lymphoma, and one case (3.4%) as metastasis. HP revealed nine cases (31%) of NHL, five cases (17.2%) of reactive lymph nodes and all the diagnosed metastatic and Hodgkin's lymphoma. Considering histology as a gold standard method in diagnosis, the sensitivity, specificity, PPV and NPV of FNAC/FCI in differentiate malignant and benign lesion were 73.9%, 83.3%, 94.4%, and 45.5%, respectively and in differentiate NHL from others were 75%, 93.8%, 90%, and 83.3%, respectively. Cytology and HP in addition to FCI and HP are significantly different from determination of NHL lesions point of view (P = 0.001 and P < 0.0001, respectively). However, FCI can be considered as an adjunctive method for Cytology especially because Cytology is not competent enough to differentiate between benign lesions and Lymphoma. Additionally, FCI is shown to be an accurate method in classifying NHL.  相似文献   
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Bone marrow-derived mesenchymal stem cells (MSCs) have the capacity to regenerate renal tubule epithelia and repair renal function without fusing with resident tubular cells. The goal of the present project was to investigate the role of MSCs secreted cytokines on tubule cell viability and regeneration after a toxic insult, using a conditionally immortalized human proximal tubule epithelial cell (ciPTEC) line. Gentamicin was used to induce nephrotoxicity, and cell viability and migration were studied in absence and presence of human MSC-conditioned medium (hMSC-CM) i.e. medium containing soluble factors produced and secreted by MSCs. Exposure of ciPTEC to 0–3000 μg/ml gentamicin for 24 h caused a significant dose-dependent increase in cell death. We further demonstrated that the nephrotoxic effect of 2000 μg/ml gentamicin was recovered partially by exposing cells to hMSC-CM. Moreover, exposure of ciPTEC to gentamicin (1500–3000 μg/ml) for 7 days completely attenuated the migratory capacity of the cells. In addition, following scrape-wounding, cell migration of both untreated and gentamicin-exposed cells was increased in the presence of hMSC-CM, as compared to exposures to normal medium, indicating improved cell recovery. Our data suggest that cytokines secreted by MSCs stimulate renal tubule cell regeneration after nephrotoxicity.  相似文献   
20.
The sinonasal microbiome remains poorly defined, with our current knowledge based on a few cohort studies whose findings are inconsistent. Furthermore, the variability of the sinus microbiome across geographical divides remains unexplored. We characterize the sinonasal microbiome and its geographical variations in both health and disease using 16S rRNA gene sequencing of 410 individuals from across the world. Although the sinus microbial ecology is highly variable between individuals, we identify a core microbiome comprised of Corynebacterium, Staphylococcus, Streptococcus, Haemophilus and Moraxella species in both healthy and chronic rhinosinusitis (CRS) cohorts. Corynebacterium (mean relative abundance = 44.02%) and Staphylococcus (mean relative abundance = 27.34%) appear particularly dominant in the majority of patients sampled. Amongst patients suffering from CRS with nasal polyps, a statistically significant reduction in relative abundance of Corynebacterium (40.29% vs 50.43%; P = .02) was identified. Despite some measured differences in microbiome composition and diversity between some of the participating centres in our cohort, these differences would not alter the general pattern of core organisms described. Nevertheless, atypical or unusual organisms reported in short-read amplicon sequencing studies and that are not part of the core microbiome should be interpreted with caution. The delineation of the sinonasal microbiome and standardized methodology described within our study will enable further characterization and translational application of the sinus microbiota.  相似文献   
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