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41.
Estrogen sulfotransferase (EST/SULT1E1) is known to catalyze the sulfoconjugation and deactivation of estrogens. The goal of this study is to determine whether and how EST plays a role in human adipogenesis. By using human primary adipose-derived stem cells (ASCs) and whole-fat tissues from the abdominal subcutaneous fat of obese and nonobese subjects, we showed that the expression of EST was low in preadipocytes but increased upon differentiation. Overexpression and knockdown of EST in ASCs promoted and inhibited differentiation, respectively. The proadipogenic activity of EST in humans was opposite to the antiadipogenic effect of the same enzyme in rodents. Mechanistically, EST promoted adipogenesis by deactivating estrogens. The proadipogenic effect of EST can be recapitulated by using an estrogen receptor (ER) antagonist or ERα knockdown. In contrast, activation of ER in ASCs inhibited adipogenesis by decreasing the recruitment of the adipogenic peroxisome proliferator-activated receptor γ (PPARγ) onto its target gene promoters, whereas ER antagonism increased the recruitment of PPARγ to its target gene promoters. Linear regression analysis revealed a positive correlation between the expression of EST and body mass index (BMI), as well as a negative correlation between ERα expression and BMI. We conclude that EST is a proadipogenic factor which may serve as a druggable target to inhibit the turnover and accumulation of adipocytes in obese patients.  相似文献   
42.
We describe a modification and post‐functionalization technique for a donor–acceptor–donor type monomer; 6‐(4,7‐bis(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐5‐yl)‐2H‐benzo[d][1,2, 3]triazol‐2‐yl)hexan‐1‐amine. Folic acid was attached to the fluorescent structure. The conjugation was confirmed via NMR and Fourier transform infrared analyses. Cytotoxicity was investigated and the comparison of association of targeted monomeric structures in tumor cells was monitored via fluorescence microscopy. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:952–959, 2014  相似文献   
43.
Decontamination of suspected packages, such as sealed envelopes, liquids and tools that are likely contaminated with biological agents is of great importance. In this study, we aimed to determine the gamma radiation dose required for the decontamination of paper, fabric and liquid materials without causing any damage to the structure of these materials. Each study group included 11 pieces of paper, fabric and sterile saline contaminated with 0.8 × 105 virulent Bacillus anthracis (B. anthracis) spores. These specimens were exposed to doses of 5.49, 11.58, 17.21, 21.75, 27 and 33.1 kilogray (kGy) of gamma radiation from a cobalt-60 source. After irradiation of all the samples, a viability assessment of the B. anthracis spores was performed. It was found that full decontamination was achieved with 11.58 kGy on the paper samples and 17.21 kGy on the fabric and liquid samples. It was concluded that a dose of 20 kGy of gamma radiation may be recommended for the inactivation of B. anthracis for some surfaces when especially sensitive and valuable materials cannot be wet decontaminated were exposed. In addition, serologic and molecular assays of the suspected packets can be performed for forensic purposes without damaging existing evidence in a bioterror incident.  相似文献   
44.
Liposome (spherical vesicles) and cochleate (multilayer crystalline, spiral structure) formulations containing raloxifene have been developed having dimethyl-β-cyclodextrin (DM-β-CD) or sodium taurocholate (NaTC). Raloxifene was approved initially for the treatment of osteoporosis but it is also effective on breast tissue and endometrial cells. Raloxifene inhibits matrix metalloproteinase-2 (MMP-2) enzyme, which is known to be responsible for tumor invasion and the initiation of angiogenesis during the tumor growth. Therefore, raloxifene was selected as a model drug. A series of raloxifene-loaded liposome and cochleate formulations were prepared. In vitro release studies and in vivo tests were performed. Breast cancer cell lines (MCF-7) were also used to find the most effective formulation. Highest antitumor activity was observed, and MMP-2 enzyme was also found to be inhibited with raloxifene-loaded cochleates containing DM-β-CD. These developed formulations can be helpful for further treatment alternatives and new strategies for cancer therapy.  相似文献   
45.
In the present work, 12 new 2-(5-substituted-benzothiazol-2-ylsulfanyl)-N-(substitutedbenzyl)-N-(4-substitutedphenyl) acetamide derivatives (4a–l) was designed and synthesized. The structures of the synthesized compounds were clarified using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), carbon-13 nuclear magnetic resonance (13C-NMR) and high-resolution mass spectrometry (HRMS) spectral data. Purity of synthesized compounds was checked by high-performance liquid chromatography (HPLC) analyses and purity ratio was found between 96.5–99.9%. The inhibitory activity of the compounds against MAO-A and MAO-B enzymes was evaluated by using in vitro flurometric method in which kynuramine was used as a substrate. Most of the compounds exhibited more selective inhibitory activity towards monoamine oxidase B (MAO-B) than monoamine oxidase A (MAO-A). Compound 4h was determined as the most potent compound against both enzyme types. The MAO-B enzyme kinetic of the compound 4h was studied and nature of MAO-B inhibition, caused by this compound, was investigated. The graphical analysis of steady-state inhibition data indicated that compound 4h is a mixed type inhibitor. Theoretical calculation of absorption, distribution, metabolism, excretion (ADME) properties for the synthesized compounds was also carried out and observed data supported the potential of compound 4h.  相似文献   
46.
Cotton stalk is a widely distributed and abundant lignocellulosic waste found in Turkey. Because of its rich xylose content, it can be a promising source for the production of xylitol. Xylitol can be produced by chemical or biotechnological methods. Because the biotechnological method is a simple process with great substrate specificity and low energy requirements, it is more of an economic alternative for the xylitol production. This study aimed to use cotton stalk for the production of xylitol with Candida tropicalis Kuen 1022. For this purpose, the combined effects of different oxygen concentration, inoculum level and substrate concentration were investigated to obtain high xylitol yield and volumetric xylitol production rate. Candida tropicalis Kuen 1022 afforded different concentrations of xylitol depending on xylose concentration, inoculum level, and oxygen concentration. The optimum xylose, yeast concentration, and airflow rate for cotton stalk hydrolysate were found as 10.41 g L?1, 0.99 g L?1, and 1.02 vvm, respectively, and under these conditions, xylitol yield and volumetric xylitol production rate were obtained as 36% and 0.06 g L?1 hr?1, respectively. The results of this study show that cotton stalk can serve as a potential renewable source for the production of xylitol.  相似文献   
47.

Objective

Endothelial dysfunction and microvascular damage play a crurical role in the pathogenesis of erectile dysfunction (ED). Insulin-like growth factor-1 (IGF-1) is one of the growth factors that have a wide range of biologic effects. IGF-1 is an important mediator of cell growth, differentiation and transformation in various tissues. The purpose of the current study was to determine the association between IGF-1 levels and ED.

Materials and methods

All men were evaluated for ED and divided into two groups: 80 patients suffering from ED for >?1 year and 80 subjects without ED were enrolled as a control group in this study. Diagnosis of ED was based on the International Index of Erectile Function Score-5. IGF-1 levels were measured in serum by an automated chemiluminescence immunoassay. The relationship between IGF-1 levels and ED scores in patients was statistically evaluated.

Results

The mean age of patients in ED group was 60.4?±?11.3 years and 55.4?±?9.6 in control group. The plasma IGF-1 levels were significantly lower in ED than in control group (96.5?±?38.3 and 132.5?±?53.3 ng/ mL, respectively, P?<?0.001). The IGF-1 levels were positively correlated with ED score (r?=?0.623, P?<?0.01).

Conclusion

In this study serum IGF-1 levels were found to be associated with endothelial dysfunction that predicts ED. Serum IGF-1 level appears to be a specific predictor of ED, and it might be used in early prediction of ED in male population.
  相似文献   
48.
Most of the commercialized Bt crops express cry genes under 35S promoter that induces strong gene expression in all plant parts. However, targeted foreign gene expression in plants is esteemed more important as public may be likely to accept ‘less intrusive’ expression of transgene. We developed plant expression constructs harboring cry1Ac gene under control of wound-inducible promoter (AoPR1) to confine Bt gene expression in insect wounding parts of the plants in comparison with cry1Ac gene under the control of 35S promoter. The constructs were used to transform four Turkish cotton cultivars (GSN-12, STN-468, Ozbek-100 and Ayhan-107) through Agrobacterium tumefaciens strains GV2260 containing binary vectors p35SAcBAR.101 and AoPR1AcBAR.101 harboring cry1Ac gene under control of 35S and AoPR1, respectively. Phosphinothricin (PPT) was used at concentration of 5 mg L?1 for selection of primary transformants. The primary transformants were analyzed for transgene presence and expression standard molecular techniques. The transformants exhibited appreciable mortality rates against larvae of Spodoptera exigua and S. littoralis. It was found that mechanical wounding of T 1 transgenic plants was effective in inducing expression of cry1Ac protein as accumulated levels of cry1Ac protein increased during post-wounding period. We conclude that use of wound-inducible promoter to drive insecticidal gene(s) can be regarded as a valuable insect-resistant management strategy since the promoter activity is limited to insect biting sites of plant. There is no Bt toxin accumulation in unwounded plant organs, seed and crop residues, cotton products and by-products, thus minimizing food and environmental concerns.  相似文献   
49.
The aim of this study was to develop chitosan film containing fucoidan and to investigate its suitability for the treatment of dermal burns on rabbits. Porous films, thickness between 29.7 and 269.0 μm, were obtained by the solvent dropping method. Water vapor permeability (3.3–16.6/0.1 g), the swelling (0.67–1.77 g/g), tensile strength (7.1–45.8 N), and bioadhesion (0.076–1.771 mJ/cm2) of the films were determined. The thinnest films were obtained with the lowest chitosan concentration (P<.05). The water absorption capacity of the films sharply increased with the freeze-drying technique. The film having the thickness of 29.7 μm showed the highest amount of moisture permeability (16.6 g/0.1 g). Higher chitosan concentration significantly increased tensile strength of the films (P<.05). Using higher concentration of lactic acid made films more elastic and applicable, and these films were selected for in vivo studies. Seven adult male New Zealand white rabbits were used for the evaluation of the films on superficial dermal burns. Biopsy samples were taken at 7, 14, and 21 days after wounding, and each wound site was examined macroscopically and histopathologically. After 7 days treatment, fibroplasia and scar were observed on wounds treated with fucoidan-chitosan film. The best regenerated dermal papillary formation, best reepithelization, and the fastest closure of wounds were found in the fucoidan-chitosan film treatment group after 14 days compared with other treatment and control groups. It can be concluded that fucoidan-chitosan films might be a potential treatment system for dermal burns and that changing formulation variables can modulate the characterizations of the films. Published: May 24, 2007  相似文献   
50.
A 2-D reference map in pI range 3-10 was constructed for the soluble protein fraction of Phanerochaete chrysosporium growing vegetatively under standard conditions. Functional annotation could be made for 517 spots out of 720 that were subjected to MALDI-TOF-MS analysis, according to the specific accession numbers from the P. chrysosporium genomic database. Further analysis of the data revealed 314 distinct ORFs, 118 of which yielded multiple spots on the master gel. Functional classification of the proteins was made according to the eukaryote orthologous groups defined in the organism's genome website. The functional class of PTMs, protein turnover and chaperones was represented with the highest number (63) of the identified ORFs. Six proteins were assigned to the hypothetical proteins and 29 were predicted to have a signal peptide sequence. Subcellular localization predictions were also made for the identified proteins. Of the protein spots detected on the master gel, 380 were found to be probably phosphorylated and 96 of these matched to the identified proteins. The reference map was efficiently used in the identification of the proteins differentially expressed under cadmium and copper stress. Three new ribosomal proteins as well as zinc-containing alcohol dehydrogenase, glucose-6-phosphate isomerase, flavonol/cinnamoyl-CoA reductase, H+-transporting two-sector ATPase, ribosomal protein S7, ribosomal protein S21e, elongation factor EF-1 alpha subunit were demonstrated as the most strongly induced.  相似文献   
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