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81.

Background:

Ovarian tissue cryopreservation is an alternative strategy to preserve the fertility of women predicted to undergo premature ovarian failure. This study was designed to evaluate the expression of folliculogenesis-related genes, including factor in the germline alpha (FIGLA), growth differentiation factor-9 (GDF-9), follicle-stimulating hormone receptor (FSHR), and KIT LIGAND after vitrification/warming of human ovarian tissue.

Methods:

Human ovarian tissue samples were collected from five transsexual women. In the laboratory, the ovarian medullary part was removed by a surgical blade, and the cortical tissue was cut into small pieces. Some pieces were vitrified and warmed and the others were considered as non-vitrified group (control). Follicular normality was assessed with morphological observation by a light microscope, and the expression of FIGLA, KIT LIGAND, GDF-9,, and FSHR genes was examined using real-time RT-PCR in both the vitrified and non-vitrified groups.

Results:

Overall, 85% of the follicles preserved their normal morphologic feature after warming. The percentage of normal follicles and the expression of FIGLA, KIT LIGAND, GDF-9, and FSHR genes were similar in both vitrified and non-vitrified groups (P > 0.05).

Conclusion:

Vitrification/warming of human ovarian tissue had no remarkable effect on the expression of folliculogenesis-related genes. Key Words: Vitrification, Gene expression, Humans  相似文献   
82.
Potassium (K) is one of the major essential nutrient elements whose application of organic or nano-chelate-fertilizers has received increased attention recently. Cadmium (Cd) contamination in agricultural soils and environment is increasing due to the over-application of Cd-containing phosphate fertilizers. But few studies have been carried out on the environmental influences of K-nano-chelate fertilizers especially on Cd-polluted soils. Therefore, the effects of K-fertilizer application in different rates (0, 100 and 200 mg kg?1 soil) and forms (KCl, K2SO4 and K-nano-chelate) on Cd content and partitioning in Ocimum basilicum grown on an artificially Cd-contaminated calcareous soil (with 40 mg Cd kg?1 soil) were studied under greenhouse conditions. Cadmium decreased shoot dry weight (SDW), but did not affect root dry weight (RDW) and no consistent trend was observed with applied K. Cadmium increased shoot and root Cd concentration or uptake. KCl and K2SO4 increased shoot Cd concentration compared to that of control, whereas K-nano-chelate did not affect it. In Cd-treated soils the mean value of Cd translocation factor (ratio of Cd concentration in shoots to that of roots) decreased by 60% as compared to that of the control. Application of 100 mg K-K2SO4 and 100 and 200 mg K-nano-chelate increased the Cd translocation factor by 49, 59 and 112% in Cd-treated soils, respectively. In Cd-treated soils, greater amounts of Cd accumulated in roots. K-nano-chelate could mitigate the adverse effect of Cd on SDW and Cd accumulation in plants grown on Cd-polluted soils, so the risk of Cd entrance to the food chain is reduced (however, in Cd-untreated soils, K-nano-chelate increased the Cd translocation factor higher than other K sources). In Cd-polluted soils KCl was the most inappropriate fertilizer that may intensify Cd accumulation in plants. However, it may be useful in the phytoremediation of Cd-polluted soils.  相似文献   
83.
The study aims at performing a comparative assessment of two types of burn wound treatment. The present study was designed to prepare crosslinked and blended two natural polymers nanofiber scaffolds using gelatin (GE) and hyaluronic acid (HA). The GE/HA composite nanofibrous membranes with varied GE/HA weight ratio have also been successfully fabricated by an electrospinning method. The average diameter of GE/HA fibers was in the range of 20 to 150 nm. In vivo efficacy was also investigated based on a deep second degree burns model for Wistar rats. At 14 days post-operation, the dermal defect basically recovered its normal condition. A percentage of wound closure of GE/HA composite nanofibrous membranes and ChitoHeal gel reached up to 81.9 % and 77.8 % respectively, compared with 65 % of the untreated control (p<0.05). Also, histological parameters were assessed on postoperative day 7 and 14. The results of in vivo experiments showed that more epidermis was formed in the gel and scaffold groups compared to the control group. The numbers of inflammatory cells in these two groups were also smaller as compared with the control group, which could well be the reason for the delayed healing in the control group.  相似文献   
84.
Since studies on the effects of selenium (Se) supplementation in water-stressed plants have mainly focused on cereal crops, the specific reports regarding Se-mediated adaptation to drought stress in medicinal vegetables are scant. Thus, we investigated the responses of Melissa officinalis to Se supplementation. Selenium contents were increased in leaves and grains by supplemental Se. Selenium foliar application at 1 mg l?1 could be useful to increase the vegetative and reproductive growth of Se-enriched plants under well-watered conditions but at 20 mg l?1 led to toxicity and caused damage to shoots. Drought stress significantly inhibited plant growth by chlorophyll degradation and reduced net carbon dioxide (CO2) assimilation rate. Although Se at 1 mg l?1 could increase biomass production under well-watered conditions in addition to the stimulation of antioxidant system under water stress, it could not ameliorate the negative effect of drought on productivity.  相似文献   
85.
Little information is available regarding the effect of sewage sludge biochar on soil properties and crop yield. Thus, our objective was to evaluate the effect of sewage sludge (S) and its biochar (B) on maize shoot yield, nutrients and heavy metals uptake in two calcareous soils. The amendments were applied at the rates of 0, 10, 20 and 40 Mg ha?1. Moreover, NK treatment was included to compare the effects of S and B with conventional fertilization. At harvest time, plant shoots and soil samples were collected for yield, nutrients uptake and chemical analyses. The highest shoot dry matter was obtained in the S treatment. The B application in the clay loam and loam soils resulted in 5.2% increment and 17.7% decrement of shoot dry matter relative to the control, respectively. Shoot dry matter in the NK treatment was significantly higher than in the control. B application decreased Fe, Zn, Mn, Cu and Pb uptake by maize shoot. DTPA-extractable Pb in B-amended soils was lower than in control, while an inverse trend was obtained for available Fe, Zn, Mn and Cu. Biochar application at the rate of 7.3 Mg ha?1 might be suggested for maize cultivation in clay loam soils.  相似文献   
86.
Basalt fibers were surface modified by a new method using nanostructured porous silica aerogel via sol-gel process followed by ambient pressure drying method. FTIR, FE-SEM, and nitrogen adsorption analysis were used for characterization of silica aerogel particles which proved their mesoporous structure with pore size of 7 nm, high porosity and low density. FTIR spectra indicated the formation of silica aerogel on the basalt fibers surface. SEM analysis proved the surface modification of basalt fibers and quantitative measurement showed an increase of 2-fold in the surface roughness compared to unmodified surface fibers. A decrease of 42 % in the density of the surface modified basalt fibers was observed. Also, acoustical properties measurement showed that sound absorption coefficient was increased by 25 %. The obtained results show that silica aerogel structure can affect the physical properties of surface modified basalt fibers. Two silica aerogels with different density and porosity were used in this work.  相似文献   
87.
Nylon 6 fabric with self-cleaning properties was prepared by corona discharge pre-treatment and coating with TiO2 nanoparticles (NPs) using pad-dry-cure technique. The self-cleaning property was studied by discoloration of methylene blue (MB), ketchup, tea and coffee stains from the corona+TiO2 treated nylon-6 fabric. Color difference (ΔΕ*), reflectance (R) and K/S of MB stain were investigated by diffuse reflectance spectrophotometry. The MB stain was almost completely removed from the corona+TiO2 treated nylon surface after 24 h under UV light/daylight irradiation. Both of these phenomena (corona and TiO2) led to an increase in the discoloration of stains under UV and daylight irradiations. The EDS analysis showed an increase in the concentration of deposited TiO2 NPs coating after corona treatment. The FE-SEM images revealed that the surface of nylon 6 was coarser after the corona treatment. Also, the FE-SEM micrographs exhibited that a uniform layer of TiO2 NPs was formed on the corona treated nylon fabric. The corona+TiO2 treated nylon illustrated antibacterial activity against E. coli and B. subtillis microorganisms. The EDS and FE-SEM analysis confirmed that after 5 washing cycles, the amount of TiO2 NPs was higher on the surface of corona+TiO2 treated nylon than that of the fabric only treated with TiO2 without corona pretreatment. This result justifies that the corona+TiO2 treated nylon fabric with appropriate self-cleaning property can be applied cost-effectively in the textile industry.  相似文献   
88.
Soils are continuously exposed to large amounts of engineered nanoparticles, especially silver nanoparticles (AgNPs), which can affect the activity, stability, and specificity of microbial enzymes. Therefore, the measurement of specific enzyme activity can be used to identify major changes in soil environments. Accordingly, the aim of the present study was to investigate the effects of AgNPs on soil enzymes that play critical roles in mineralizing carbon and nutrients in soil. Soil samples (silt loam and sandy loam) were collected from the surface layer (0–15 cm) of a field at the George Washington Carver Farm, Lincoln University of Missouri, USA. The soils were then treated with AgNP solutions at 0, 1 600, or 3 200 μg Ag kg~(-1) dry soil, using either 10- or 50-nm AgNPs and a randomized complete block design, with three replicates per treatment. The AgNP-treated soil samples were homogenized and incubated for one month, and soil acid phosphatase, β-glucosaminidase, β-glucosidase, and arylsulfatase activities were measured after one hour, one week, and one month of incubation. The activities of all four enzymes were reduced by AgNP treatment after one hour and one week.However, AgNP size had no effect. After one month of incubation, the AgNP treatments had mixed effects, which suggests that soil enzymes are only affected on a short-term basis. Further studies are required to determine the mechanisms by which AgNPs reduce soil enzyme activity.  相似文献   
89.

The aims of the present study were to investigate the prevalence of some virulence genes and also determine the antimicrobial resistance pattern of E. coli isolated from bovine with subclinical mastitis. The milk of 502 cows was collected from 8 dairy herds in the southwest of Iran. Conventional biochemical tests were used for identification of E. coli at the species level. Antimicrobial susceptibility patterns of E. coli isolates were determined by disc agar diffusion method and polymerase chain reaction (PCR) was used for detection of seven virulence genes including f17A, afaE-8, afaD-8, eaeA, cnf1, cnf2, and iucD. Seventy (13.94%) isolates of E. coli were identified in 502 milk samples. The highest rate of resistance was observed against tetracycline (18.6%), while none of the isolates were resistant to streptomycin. Eight (11.5%) out of 70 E. coli isolates carried at least one of the virulence genes. The afaD-8 was the most prevalent gene detected in 5 (7.1%) isolates. The afaE-8, iucD, and eaeA were detected in 3, 3, and 2 isolates respectively. Low prevalence of virulence factors may be indicating that most of the E. coli isolates originated from the commensal flora of cows and enter to the udders via environment contamination with feces.

  相似文献   
90.
Determination of chilling and heat requirements of pistachio (Pistacia vera L.) cultivars is important for satisfactory growth and development, particularly when large-scale commercial production is desired. This experiment was conducted to determine chilling requirement inducing vegetative and flower buds of Kalle-Ghuchi, Owhadi, Ahmad-Ahgaei, and Akbari pistachio. Shoots with enough vegetative and flower buds were taken from pistachio trees during autumn 2007 and 2008 when temperature reached to 15°C. Cuttings with flower buds were kept under (5 ± 1)°C for 0, 600, 650, 700, 750, 800, 850, 900, 950, 1 000, 1 050, 1 100, 1 150, 1 200, 1 250, and 1 300 h, respectively, and cuttings with vegetative buds were kept at 51°C until 1 500 h. The results indicated that pistachio cultivars requite chilling time between 750-1 400 h and heat requirements between 8 852-15 420 growing degree hours (GDH). Consequently, Kalle-Ghuchi had the lowest chilling (750-950 h), and heat (8 852-9 768 GDH) requirements, Ahmad-Aghaei and Owhadi had intermediate (1 000-1 250 h, 10 656- 13 320 GDH) and Akbari had the highest chilling (1 200-1 400 h) and heat (11 863-15 420 GDH) requirement.  相似文献   
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