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1.

Purpose

The present paper concerns the distribution and mobility of heavy metals (Cu, Pb, Zn and Fe) in the soils of some abandoned mine sites in Italy and their transfer to wild flora.

Materials and methods

Soils and plants were sampled from mixed sulphide mine dumps in different parts of Italy, and the concentrations of heavy metals were determined.

Results and discussion

The phytoremediation ability of Salix species (Salix eleagnos, Salix purpurea and Salix caprea), Taraxacum officinale and P?lantago major for heavy metals and, in particular, zinc was estimated. The results showed that soils affected by mining activities presented total Zn, Cu, Pb and Fe concentrations above the internationally recommended permissible limits. A highly significant correlation occurred between metal concentrations in soils.

Conclusions

The obtained results confirmed the environmental effects of mine waste; exploring wild flora ability to absorb metals, besides metal exploitation, proved a useful tool for planning possible remediation projects.
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2.
Soil phosphorous (P) uptake mechanisms by the interaction of plants and soil microorganisms benefit plant growth with preparing agriculture inoculants. But it is influenced by soil factors. The present study was performed to identify three effective strains of phosphate solubilizing bacteria (PSB) on the basis of 16S rDNA sequence in vitro. Bacillus lentus strain PS5, Bacillus licheniformis strain PS7 and Pseudomonas putida strain PS13 were isolated from an alkaline soil in Iran and the rhizosphere of Beta vulgaris and Solanum tuberosom. Their high root colonization ability and P solubilizing activity was detected in relation to soil physical and chemical properties influenced by environmental factors including salinity of 800 mM/L and temperature of 42 °C.  相似文献   
3.
This study aimed to provide the analysis of clinical presentation, results of laboratory and imaging investigations as well as clinical outcome of children with cholestasis. Infants with neonatal cholestasis referred to Children's Hospital from 2002 to 2007 were participated in the study in a cross-sectional prospective study. Appropriate diagnostic criteria and tests were employed for diagnosis the underlying etiologies of neonatal cholestasis. One year mortality rate was determined. One hundred twenty one infants, 75 males and 46 females, with the mean age of 58.3 +/- 15.3 (14-120) days were enrolled in study. Jaundice (94.2%) and hepatomegaly (66.1%) were the most frequent symptom and signs on admission. Idiopathic neonatal hepatitis (36.4%), extrahepatic biliary atresia (24.8%), metabolic disease (20.7%), intrahepatic ductal paucity (10.7%), intrauterine infection (3.3%) were the most frequent causes of neonatal cholestasis. One year mortality was 5.8%. There is still not one effective and specific diagnostic method in differentiating between the causes of cholestasis in the newborns and infants. Some potentially important differences in the disease pattern, initial presentation and long-term outcome are suggested from the present study when compared to previous reports from other parts of the world.  相似文献   
4.
Background: Integrins are heterodimeric glycoprotein receptors that regulate the interaction of cells with extracellular matrix and may have a critical role in implantation. The aim of this study was to investigate the effect of ovulation induction on the expression of α4, αv, β1, and β3 integrins in mouse blastocyst at the time of implantation. Methods: The ovarian stimulated and non-stimulated pregnant mice were sacrificed on the morning of 5th day of pregnancy. The blastocysts were collected, and the expression of αv, α4, β1, and β3 integrins was examined using real-time RT-PCR and immunocytochemical techniques, then their ovarian hormones were analyzed at the same time. The implantation sites in uterine horns of other pregnant mice in both groups were determined under a stereomicroscope on the 7th day of pregnancy. Results: The results showed that the expression of αv, β1, and β3 integrins in both mRNA and protein levels was significantly lower in the ovarian stimulated group than the control group, and the maximum ratio of expression was belonged to β1 molecule (P>0.05). Conclusion: The implantation rate in superovulated mice was significantly lower than control mice. It was suggested that ovulation induction decreased the expression of αv, β1, and β3 integrins of mouse blastocysts. Key Words: Blastosyst, Integrins, Implantation  相似文献   
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6.
Closely related signals often lead to very different cellular outcomes. We found that the differentiation of human mesenchymal stem cells into bone-forming cells is stimulated by epidermal growth factor (EGF) but not platelet-derived growth factor (PDGF). We used mass spectrometry-based proteomics to comprehensively compare proteins that were tyrosine phosphorylated in response to EGF and PDGF and their associated partners. More than 90% of these signaling proteins were used by both ligands, whereas the phosphatidylinositol 3-kinase (PI3K) pathway was exclusively activated by PDGF, implicating it as a possible control point. Indeed, chemical inhibition of PI3K in PDGF-stimulated cells removed the differential effect of the two growth factors, bestowing full differentiation effect onto PDGF. Thus, quantitative proteomics can directly compare entire signaling networks and discover critical differences capable of changing cell fate.  相似文献   
7.
Background: To achieve multiple oocytes for in vitro fertilization, ovulation induction is induced by gonadotropins; however, it has several effects on oocytes and embryo quality and endometrium receptivity. The aim of this study was to assess ultrastructural changes of corpus luteum after ovarian induction using human menopausal gonadotropin (HMG) and human chorionic gonadotropin (HCG) during luteal phase at implantation period. Methods: Female NMRI mice (6-8 weeks) were divided into control and stimulated groups. In the control group, the mice were rendered pseudopregnant and in the ovarian induction group, the mice were rendered pseudopregnant after the ovarian induction. The samples were obtained from the ovary in each group at the same time during luteal phase at implantation period. Ultrastructural changes were assessed using electron microscopy study. Results: Our results displayed some identifiable changes in ultrastructure of corpus luteum in ovarian induction group. These changes included enhancement of the apoptosis and intercellular space, whereas the angiogenesis was decreased. The findings indicated a decline in organelle density in the cytoplasm of ovarian induction, such as mitochondria, endoplasmic reticulum and polyribosome. Furthermore, chromatin condensation of nuclei was observed in some cells. Conclusion: The ovarian induction using HMG and HCG resulted in some ultrastructural changes on the corpus luteum at implantation period, which could affect on the pregnancy rate.Key Words: Corpus luteum, Luteal phase, Ultrastructure, Ovarian induction  相似文献   
8.

The effects of screened lactic acid bacteria strains were evaluated on growth performance, humoral immunity, and IGF-1 gene expression in broiler chickens. The three dietary groups of negative control fed basal diet, the native LAB probiotic group (NP), and PrimaLac commercial LAB probiotic (PC) were studied. The results revealed that NP and PC diets significantly improved feed conversion ratio and increased body weight, as well as relative weight of carcass compared with group fed NC diet (P?<?0.05). Lymphocyte level was significantly increased in birds fed NP and PC (P?<?0.01), while serum triglycerides and total cholesterol levels were significantly decreased compared with the NC (P?<?0.05). Significant increases were observed in antibody titers against Newcastle disease virus of vaccinated birds (P?<?0.03), and morphological analysis of ileum revealed significant increases (P?<?0.05) in the villus height and villus height/crypt depth in birds fed NP and PC compared with the NC. The dietary significantly increased Lactobacillus spp. (P?<?0.05), while Escherichia coli (P?<?0.04) populations were significantly decreased, and also, the expression of IGF-1 gene in liver tissue of broilers fed NP and PC was significantly increased compared with the NC (P?<?0.05). These results indicated that the identified native LAB strains can be used commercially as a low-cost probiotic in poultry industry of Iran.

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9.
10.

Purpose

Soil enzyme activities are sensitive indicators of soil quality reflecting effects of land management. This study aims to monitor the effects of four crop rotation systems (rice-rice-rice: R-R-R, soya-rice-rice: S-R-R, fallow-rice: F-R and pea-soya-rice: P-S-R) on the activities of six important soil enzymes involved in C, N, P, and S cycling and soil properties during rice growth.

Materials and methods

Four rice plots with different rotation systems were investigated before rice planting and during the phenological cycle in a paddy soil from the Veneto region, Italy; sampling of soils (0–15 cm) was carried out four times during growing season (three replicates). A total of 48 samples were air dried, for some chemical (soil pH, electrical conductivity, soil organic carbon, extractable P), physical (particle size distribution), and biochemical measurements (enzymatic assays and extraction of soil DNA). Moreover, the total concentration of trace and macro- and microelements were measured for assessing element levels and possible contamination of soils.

Results and discussion

The results demonstrated that compared with field moist soil, drained soil conditions resulted in a significant increase (P < 0.05) of β-glucosidase, arylsulfatase, alkaline and acid phosphomonoesterase, leucine aminopeptidase, and chitinase activities in almost all rotations. The results obtained point to a land with high soil contamination by Li and TI. Moreover, soil DNA was negatively correlated to soil TI stress (r = ? 0.41, p ? 0.01). The P–S–R rotation had the highest TI concentration in April and it is likely to be responsible for the lowest enzyme activities in the field-moist condition.The total concentrations of most studied elements (Al, As, Be, Cd, Co, Cr, Cu, Fe, Ni, Pb, Sb, Sn, Sr, V, Zn) in the soil samples fell within the natural geochemical background concentration levels.

Conclusions

The obtained results suggest that the activity of most enzymes decreases in the different experimental conditions with the following order: drained soil > late waterlogging > early waterlogging > moist soil. However, the response of enzymes to waterlogging differed with the chemical element and the cropping pattern. The best rotation system for chitinase, leucine aminopeptidase, and β-glucosidase activity (C and N cycles) was R-R-R, while for arylsulfatase, alkaline, and acid phosphatase activities (S and P cycles), it was the S-R-R.
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