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11.
In this study, the aphrodisiac activities of Crocus sativus stigma aqueous extract and its constituents, safranal and crocin, were evaluated in male rats. The aqueous extract (80, 160 and 320 mg/kg body wt.), crocin (100, 200 and 400 mg/kg body wt.), safranal (0.1, 0.2 and 0.4 ml/kg), sildenafil (60 mg/kg body wt., as a positive control) and saline were administered intraperitoneally to male rats. Mounting frequency (MF), intromission frequency (IF), erection frequency (EF), mount latency (ML), intromission latency (IL) and ejaculation latency (EL) were the factors evaluated during the sexual behavior study. Crocin, at all doses, and the extract, especially at doses 160 and 320 mg/kg body wt., increased MF, IF and EF behaviors and reduced EL, IL and ML parameters. Safranal did not show aphrodisiac effects. The present study reveals an aphrodisiac activity of saffron aqueous extract and its constituent crocin.  相似文献   
12.
Micelle/water mixed solutions of different surface active agents were studied for their effectiveness in the extraction of polyphenolic compounds from various varieties of apples from west Azerbaijan province in Iran. The total content of polyphenolic compound in fruit extracts were determined using ferrous tartrate and Folin–Ciocalteu assays methods and chromatographic methods and compared with theme. High performance liquid chromatography is one of the most common and important methods in biochemical compound identification. The effect of pH, ionic strength, surfactant type, surfactant concentration, extraction time and common organic solvent in the apple polyphenolics extractions was studied using HPLC-DAD. Mixtures of surfactants, water and methanol at various ratios were examined and micellar-water solutions of Brij surfactant showed the highest polyphenol extraction efficiency. Optimum conditions for the extraction of polyphenolic compounds from apple occurred at 7 mM Brij35, pH 3. Effect of ionic strength on extraction was determined and 2% (W/V) potassium Chloride was determined to be the optimum salt concentration. The procedure worked well with an ultrasound bath. Total antioxidant capacity also was determined in this study. The method can be safely scaled up for pharmaceutical applications.  相似文献   
13.
Electrospun composite scaffolds show high ability to be used in regenerative medicine and drug delivery, due to the nanofibrous structure and high surface area to volume ratio. In this study, we used nanofibrous scaffolds fabricated by chitosan (CS), poly(vinyl alcohol) (PVA), carbopol, and polycaprolactone using a dual electrospinning technique while curcumin (Cur) incorporated inside of the CS/PVA fibers. Scaffolds were fully characterized via scanning electron microscopy, water contact angle, tensile measurement, hydration, protein adsorption, and wrinkled tests. Furthermore, viability of the buccal fat pad-derived mesenchymal stem cells (BFP-MSCs) was also investigated using MTT assay for up to 14 days while cultured on these scaffolds. Cell cycle assay was also performed to more detailed evaluation of the stem cells growth when grown on scaffolds (with and without Cur) compared with the culture plate. Results demonstrated that Cur loaded nanofibrous scaffold had more suitable capability for water absorption and mechanical properties compared with the scaffold without Cur and it could also support the stem cells viability and proliferation. Cur release profile showed a decreasing effect on BFP-MSCs viability in the initial stage, but it showed a positive effect on stem cell viability in a long-term manner. In general, the results indicated that this nanofibrous scaffold has great potential as a delivery of the Cur and BFP-MSCs simultaneously, and so holds the promising potential for use in various regenerative medicine applications.  相似文献   
14.
Nanocrystalline mixed metal oxides (MMO) of various metal cations were synthesized and were used for coating a piece of copper wire as a new high sensitive solid phase micro extraction (SPME) fiber in extraction and determination of BTEX compounds from the headspace of aqueous samples prior to GC-FID analysis. Under optimum extraction conditions, the proposed fiber exhibited low detection limits, and quantification limits, good reproducibility, simple and fast preparation method, high fiber capacity and high thermal and mechanical durability. These are some of the most important advantages of the new fiber. The proposed fiber was used for human hemoglobin upon interaction with benzene. Binding isotherm, Scatchard and Klotz logarithmic plots were constructed using HS-SPME-GC data, accurately. The obtained binding isotherm analyzed using Hill method. The Hill parameters have been obtained by calculating saturation parameter from the ratio of measured chromatographic peak areas in the presence and absence of hemoglobin. In this interaction, Hill coefficient and Hill constant determined as (nH = 6.14 and log KH = 6.47) respectively. These results reveal the cooperativity of hemoglobin upon interaction with benzene.  相似文献   
15.
Naringinase produced by Penicillum decombens PTCC 5248 was immobilized by entrapping it in calcium alginate beads, hen egg white, gelatin open pore matrix and covalently attaching it to activated seeds of Ocimum basilicum. Optimum pH and temperature were found to be 4, 4.5, 4.5, 3.5 and 65 °C, 60 °C respectively for enzyme immobilized by each technique mentioned. Naringinase immobilized onto activated seeds of Ocimum basilicum was active for 7 days.  相似文献   
16.
Type 1 copper (T1Cu) proteins are electron transfer (ET) proteins involved in many important biological processes. While the effects of changing primary and secondary coordination spheres in the T1Cu ET function have been extensively studied, few report has explored the effect of the overall protein structural perturbation on active site configuration or reduction potential of the protein, even though the protein scaffold has been proposed to play a critical role in enforcing the entatic or “rack‐induced” state for ET functions. We herein report circular permutation of azurin by linking the N‐ and C‐termini and creating new termini in the loops between 1st and 2nd β strands or between 3rd and 4th β strands. Characterization by electronic absorption, electron paramagnetic spectroscopies, as well as crystallography and cyclic voltammetry revealed that, while the overall structure and the primary coordination sphere of the circular permutated azurins remain the same as those of native azurin, their reduction potentials increased by 18 and 124 mV over that of WTAz. Such increases in reduction potentials can be attributed to subtle differences in the hydrogen‐bonding network in secondary coordination sphere around the T1Cu center.  相似文献   
17.
In this study, the effect of Crocus sativus (saffron) was studied on male erectile dysfunction (ED). Twenty male patients with ED were followed for ten days in which each morning they took a tablet containing 200 mg of saffron. Patients underwent the nocturnal penile tumescence (NPT) test and the international index of erectile function questionnaire (IIEF-15) at the start of the treatment and at the end of the ten days. After the ten days of taking saffron there was a statistically significant improvement in tip rigidity and tip tumescence as well as base rigidity and base tumescence. ILEF-15 total scores were significantly higher in patients after saffron treatment (before treatment 22.15±1.44; after treatment 39.20±1.90, p<0.001). Saffron showed a positive effect on sexual function with increased number and duration of erectile events seen in patients with ED even only after taking it for ten days.  相似文献   
18.
Janus kinase-2 (JAK2), a signaling molecule mediating effects of various hormones including leptin and growth hormone, has previously been shown to modify the activity of several channels and carriers. Leptin is known to inhibit and growth hormone to stimulate epithelial Na+ transport, effects at least partially involving regulation of the epithelial Na+ channel ENaC. However, no published evidence is available regarding an influence of JAK2 on the activity of the epithelial Na+ channel ENaC. In order to test whether JAK2 participates in the regulation of ENaC, cRNA encoding ENaC was injected into Xenopus oocytes with or without additional injection of cRNA encoding wild type JAK2, gain-of-function V617FJAK2 or inactive K882EJAK2. Moreover, ENaC was expressed with or without the ENaC regulating ubiquitin ligase Nedd4-2 with or without JAK2, V617FJAK2 or K882EJAK2. ENaC was determined from amiloride (50 μM)-sensitive current (I amil) in dual electrode voltage clamp. Moreover, I amil was determined in colonic tissue utilizing Ussing chambers. As a result, the I amil in ENaC-expressing oocytes was significantly decreased following coexpression of JAK2 or V617FJAK2, but not by coexpression of K882EJAK2. Coexpression of JAK2 and Nedd4-2 decreased I amil in ENaC-expressing oocytes to a larger extent than coexpression of Nedd4-2 alone. Exposure of ENaC- and JAK2-expressing oocytes to JAK2 inhibitor AG490 (40 μM) significantly increased I amil. In colonic epithelium, I amil was significantly enhanced by AG490 pretreatment (40 μM, 1 h). In conclusion, JAK2 is a powerful inhibitor of ENaC.  相似文献   
19.
Lead is a highly neurotoxic agent that particularly affects the developing central nervous system. In the current study we investigated the neuroprotective effects of exercise training and/or diferuloyl methane (DM) supplement, which is known as curcumin, on lead acetate-induced neurotoxicity in the rat hippocampus. Sixty rats were randomly divided into six groups: 1) lead acetate, 2) DM supplement, 3) endurance training, 4) training+ DM supplement, 5) sham and 6) base. The rats in the training groups performed treadmill running consisting of 15 to 22 m · min-1 for 25 to 64 min, 5 times a week for 8 weeks. All groups except sham received lead acetate (20 mg · kg-1), whereas the sham group received DM solvent. In addition, the DM and training + DM groups received DM solution (30 mg · kg-1) intraperitoneally. Chronic administration of lead acetate resulted in a significant increase in the malondialdehyde (MDA) in plasma, but not in the hippocampus. In addition, it led to significantly decreased brain-derived neurotrophic factor (BDNF) in the hippocampus and total antioxidant capacity (TAC) levels, as compared to the sham group. Treadmill running, DM supplementation, or both resulted in a significant decrease in MDA levels and significantly increased BDNF and TAC levels, as compared to the lead acetate group. These results provide a rationale for an inhibitory role of DM supplement and regular exercise in the attenuation of lead-induced neurotoxicity.  相似文献   
20.
Cluster Computing - In the distributed database systems, the relations needed by a query can be kept in several locations. This process significantly increases potential corresponding Query...  相似文献   
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