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121.
5-Fluorouracil (5-FU) is a fluoropyrimidine group antineoplastic drug with antimetabolite properties and ovotoxicity is one of the most important side effects. Silibinin (SLB) is a natural compound that is used worldwide and stands out with its antioxidant and anti-inflammatory properties. The aim of this study was to evaluate the therapeutic effect of SLB in 5-FU-induced ovototoxicity using biochemical and histological analysis. This study was carried out in five main groups containing six rats in each group: control, SLB (5 mg/kg), 5-FU (100 mg/kg), 5-FU + SLB (2.5 mg/kg), and 5-FU + SLB (5 mg/kg). The levels of ovarian malondialdehyde (MDA), total oxidant status (TOS), total antioxidant status (TAS), superoxide dismutase (SOD), catalase (CAT), 8-hydroxy-2′-deoxyguanosine (8-OHdG), tumor necrosis factor-alpha (TNF-α), myeloperoxidase (MPO), and caspase-3 were determined using spectrophotometric methods. Hematoxylin and eosin staining method was employed for histopathological examination. MDA, TOS, 8-OHdG, TNF-α, MPO, and caspase-3 levels in 5-FU group were significantly increased compared with the control group, while the levels of TAS, SOD, and CAT were decreased (p < 0.05). SLB treatments statistically significantly restored this damage in a dose-dependent manner (p < 0.05). Although vascular congestion, edema, hemorrhage, follicular degeneration, and leukocyte infiltration were significantly higher in the 5-FU group compared with the control group, SLB treatments also statistically significantly restored these damages (p < 0.05). In conclusion, SLB has a therapeutic effect on the ovarian damage induced by 5-FU via decreasing the levels of oxidative stress, inflammation, and apoptosis. It may be helpful to consider the usefulness of SLB as an adjuvant therapy to counteract the side effects of chemotherapy.  相似文献   
122.
Lactoperoxidase enzyme (LPO) is secreted from salivary, mammary, and other mucosal glands including the bronchi, lungs, and nose, which had functions as a natural and the first line of defense towards viruses and bacteria. In this study, methyl benzoates were examined in LPO enzyme activity. Methyl benzoates are used as precursors in the synthesis of aminobenzohydrazides used as LPO inhibitors. For this purpose, LPO was purified in a single step using sepharose-4B-l-tyrosine-sulfanilamide affinity gel chromatography with a yield of 9.91 % from cow milk. Also, some inhibition parameters including the half maximal inhibitory concentration (IC50) value and an inhibition constant (Ki) values of methyl benzoates were determined. These compounds inhibited LPO with Ki values ranging from 0.033±0.004 to 1540.011±460.020 μM. Compound 1 a (methyl 2-amino-3-bromobenzoate) showed the best inhibition (Ki=0.033±0.004 μM). The most potent inhibitor ( 1 a ) showed with a docking score of −3.36 kcal/mol and an MM-GBSA value of −25.05 kcal/mol, of these methyl benzoate derivatives ( 1 a – 16 a ) series are established H-bond within the binding cavity with residues Asp108 (distance of 1.79 Å), Ala114 (distance of 2.64 Å), and His351 (distance of 2.12 Å).  相似文献   
123.
Umbelopsis ramanniana was investigated to increase carotenoid production. Nine different carbon sources and six different nitrogen sources were evaluated for the maximum carotenoid production. The most effective nitrogen and carbon sources were KNO3 and lactose, respectively. Then, the optimization of medium components for enhancement of carotenoid production by Umbelopsis ramanniana was achieved using Plackett–Burman design. Box–Behnken response surface methodology was applied to further optimize carotenoid and biomass production. Carbon to nitrogen ratio, lactose concentration, and shaking speed were studied as variables in Box–Behnken design. The optimum conditions for carotenoid and biomass production were determined as 32.42 g/L of lactose concentration, 20:1 of carbon to nitrogen ratio, and shaking speed of 130 rpm. The maximum carotenoid and biomass production under optimized conditions were 1141 μg/L (β-carotene-Eq) and 13.14 g/L, respectively. When compared to the control fermentation, carotenoid, and biomass production were increased by about 2 and 1.3 folds, respectively.  相似文献   
124.
Pulmonary surfactant is a complex mixture of phospholipids and four surfactant-associated proteins (SP-A, SP-B, SP-C and SP-D). The biological functions of SP-A and SP-D are primarily twofold, namely surfactant homeostasis and host defense. The hydrophobic surfactant proteins, SP-B and SP-C, are required for achieving the optimal surface tension reducing properties of surfactant by promoting the rapid adsorption of surfactant phospholipids along the alveolar surface. Despite the promising findings, only little is known about the extrapulmonary distribution of these proteins. Therefore, in this study, the presence of SP-A, SP-B, SP-C and SP-D in early human placenta has been investigated. First-trimester placental tissues (22–56 days) were obtained from women undergoing curettage during normal pregnancies. In parallel tissue sections, vimentin, cytokeratin-7 and CD-68 immunostainings were used for the identification of mesenchymal cells, trophoblast cells and Hofbauer cells, respectively. According to immunohistochemistry (IHC) results, SP-A, SP-B, SP-C and SP-D immunoreactivities with different staining intensities were observed in trophoblastic layers of chorionic villous tree, trophoblastic cell columns, stromal cells, Hofbauer cells, angiogenic cell cords and vascular endothelium. Fetal hematopoietic cells showed a variable staining pattern for all four surfactant proteins ranging from none to strong intensity. Western blotting of tissue extracts confirmed our IHC results. The presence of surfactant glycoproteins in early human placenta may yield a very important feature of surfactants during first trimester and enables further studies of the role of surfactants in various pregnancy complications.  相似文献   
125.
This work presents a graph-based representation (a.k.a., cell-graph) of histopathological images for automated cancer diagnosis by probabilistically assigning a link between a pair of cells (or cell clusters). Since the node set of a cell-graph can include a cluster of cells as well as individual ones, it enables working with low-cost, low-magnification photomicrographs. The contributions of this work are twofold. First, it is shown that without establishing a pairwise spatial relation between the cells (i.e., the edges of a cell-graph), neither the spatial distribution of the cells nor the texture analysis of the images yields accurate results for tissue level diagnosis of brain cancer called malignant glioma. Second, this work defines a set of global metrics by processing the entire cell-graph to capture tissue level information coded into the histopathological images. In this work, the results are obtained on the photomicrographs of 646 archival brain biopsy samples of 60 different patients. It is shown that the global metrics of cell-graphs distinguish cancerous tissues from noncancerous ones with high accuracy (at least 99 percent accuracy for healthy tissues with lower cellular density level, and at least 92 percent accuracy for benign tissues with similar high cellular density level such as nonneoplastic reactive/inflammatory conditions).  相似文献   
126.
Arterial distribution of the upper lip was investigated in this study. The location, course, length, and diameter of the superior labial artery and its alar and septal branches were determined on 14 preserved cadaver heads. Another cadaver head was used to show the arterial tree by the colored silicone injection technique. The superior labial artery was the main artery of the upper lip and always originated from the facial artery. The superior labial artery was 45.4 mm in length, with a range from 29 to 85 mm. The mean distance of the origin of the superior labial artery from the labial commissura was 12.1 mm. The superior labial artery was 1.3 mm in external diameter at its origin. The mean distance of origin of the superior labial artery from the lower border of the mandible was 46.4 mm. The alar division of the superior labial artery was mostly found as a single branch (82 percent). Its mean length was 14.8 mm and the mean diameter at the origin was 0.5 mm. The distance between the origins of the superior labial artery and the septal branch was 33.3 mm. The septal branch was single in most of the cases (90 percent). The mean length of the septal branch was 18.0 mm and the diameter at its origin was 0.9 mm. After all dissections, it was concluded that the arterial distribution of the upper lip was not constant. The superior labial artery can occur in different locations unilaterally and bilaterally, with the branches showing variability.  相似文献   
127.
Prospects for facial allograft transplantation in humans   总被引:4,自引:0,他引:4  
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128.
Interactions of melatonin with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes (MLVs) were investigated as a function of temperature and melatonin concentration (1-30 mol%) by using two noninvasive techniques, namely Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). The investigation of the C-H, CO, and PO2- antisymmetric double stretching modes in FTIR spectra and DSC studies reveal that melatonin changes the physical properties of the DPPC bilayers by decreasing the main phase transition temperature, abolishing the pretransition, ordering the system in the gel phase, and increasing the dynamics of the system both in the gel and liquid crystalline phases. It also causes significant decrease in the wavenumber for the CO stretching and PO2- antisymmetric double bond stretching bands, which indicates strong hydrogen bonding The results imply that melatonin locates in the interfacial region of the membrane. Furthermore, in the DSC curve, more than one signal is observed at high melatonin concentrations (24 and 30 mol%), which indicates melatonin-induced phase separation in DPPC membranes.  相似文献   
129.
130.
Demir E  Dickson BJ 《Cell》2005,121(5):785-794
All animals exhibit innate behaviors that are specified during their development. Drosophila melanogaster males (but not females) perform an elaborate and innate courtship ritual directed toward females (but not males). Male courtship requires products of the fruitless (fru) gene, which is spliced differently in males and females. We have generated alleles of fru that are constitutively spliced in either the male or the female mode. We show that male splicing is essential for male courtship behavior and sexual orientation. More importantly, male splicing is also sufficient to generate male behavior in otherwise normal females. These females direct their courtship toward other females (or males engineered to produce female pheromones). The splicing of a single neuronal gene thus specifies essentially all aspects of a complex innate behavior.  相似文献   
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