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91.
92.
Use of microorganisms for removing mercury is an effective technology for the treatment of industrial wastewaters and can become an effective tool for the remediation of man-impacted coastal ecosystems with this metal. Nonviable biomass of an estuarine Bacillus sp. was employed for adsorbing Hg(II) ions from aqueous solutions at six different concentrations. It was observed that 0.2 g dry weight of nonviable biomass was found to remove from 0.023 mg (at 0.25 mg L(-1) of Hg(II)) to 0.681 mg (at 10.0 mg L(-1) of Hg(II)). Most of the mercury adsorption occurred during the first 20 min. It was found that changes in pH have a significant effect on the metal adsorption capacity of the bacteria, with the optimal pH value between 4.5 and 6.0 at 25 degrees C when solutions with 1.0, 5.0 and 10.0 mg L(-1) of Hg(II) were used.  相似文献   
93.
Branca F  Li G  Goyal S  Quiros CF 《Phytochemistry》2002,59(7):717-724
In the frame of the activities carried out to exploit Sicilian local cultivars of brassicas, we focused our attention on some of the potential health compounds of various local cruciferous crops. These compounds are of interest to improve the quality of the produce with the aim to develop new cultivars capable of providing functional foods able to prevent disease. In this context, we surveyed for the presence of specific glucosinolates in local cultivars of broccoli, cauliflower, kale, and in some wild species widespread in Sicily, using as control various commercial cultivars. Glucosinolate composition varied extensively among species and crops of the same species, such as cauliflower, broccoli and kale. Cultivar variation for glucosinolate profile was also observed for some crops. For example, Sicilian cultivars of cauliflower possessing colored curds displayed a high content of glucosinolates, glucoraphanin in particular, compared to white curd commercial cultivars. Also some wild species had a high content of other glucosinolates.  相似文献   
94.
Overproduction of hypochlorous acid (HOCl) has been associated with the development of a variety of disorders such as inflammation, heart disease, pulmonary fibrosis, and cancer through its ability to modify various biomolecules. HOCl is a potent oxidant generated by the myeloperoxidase-hydrogen peroxide-chloride system. Recently, we have provided evidence to support the important link between higher levels of HOCl and heme destruction and free iron release from hemoglobin and RBCs. Our current findings extend this work and show the ability of HOCl to mediate the destruction of metal-ion derivatives of tetrapyrrole macrocyclic rings, such as cyanocobalamin (Cobl), a common pharmacological form of vitamin B12. Cyanocobalamin is a water-soluble vitamin that plays an essential role as an enzyme cofactor and antioxidant, modulating nucleic acid metabolism and gene regulation. It is widely used as a therapeutic agent and supplement, because of its efficacy and stability. In this report, we demonstrate that although Cobl can be an excellent antioxidant, exposure to high levels of HOCl can overcome the beneficial effects of Cobl and generate proinflammatory reaction products. Our rapid kinetic, HPLC, and mass spectrometric analyses showed that HOCl can mediate corrin ring destruction and liberate cyanogen chloride (CNCl) through a mechanism that initially involves α-axial ligand replacement in Cobl to form a chlorinated derivative, hydrolysis, and cleavage of the phosphonucleotide moiety. Additionally, it can liberate free Co, which can perpetuate metal-ion-induced oxidant stress. Taken together, these results are the first report of the generation of toxic molecular products through the interaction of Cobl with HOCl.  相似文献   
95.

Background  

The Split ends (Spen) family are large proteins characterised by N-terminal RNA recognition motifs (RRMs) and a conserved SPOC (Spen paralog and ortholog C-terminal) domain. The aim of this study is to characterize the family at the sequence level.  相似文献   
96.
97.
ABSTRACT: BACKGROUND: Odontogenic myxoma (OM) is a benign, but locally invasive, neoplasm occurring in the jaws. However, the molecules implicated in its development are unknown. OM as well as Dental Follicle (DF), an odontogenic tissue surrounding the enamel organ, is derived from ectomesenchymal/mesencyhmal elements. To identify some protein that could participate in the development of this neoplasm, total proteins from OM were separated by two-dimensional electrophoresis and the profiles were compared with those obtained from DF, used as a control. RESULTS: We identified eight proteins with differential expression; two of them were downregulated and six upregulated in OM. A spot consistently overexpressed in odontogenic myxoma, with a molecular weight of 44-kDa and a pI of 3.5 was identified as the orosomucoid 1 protein. Western blot experiments confirmed the overexpression of this protein in odontogenic myxoma and immunohistochemical assays showed that this protein was mainly located in the cytoplasm of stellate and spindle-shaped cells of this neoplasm. CONCLUSION: Orosomucoid 1, which belongs to a group of acute-phase proteins, may play a role in the modulation of the immune system and possibly it influences the development of OM.  相似文献   
98.
Capturing and marking free‐living birds permits the study of important aspects of their biology but may have undesirable effects. Bird welfare should be a primary concern, so it is necessary to evaluate and minimize any adverse effects of procedures used. We assess short‐term effects associated with the capture, handling and tagging with backpack‐mounted transmitters of Pin‐tailed Pterocles alchata and Black‐bellied Pterocles orientalis Sandgrouse, steppe birds of conservation concern. There was a significantly higher mortality (15%) during the first week after capture than during the following weeks (< 2.5%) in Pin‐tailed Sandgrouse, but no significant temporal mortality pattern in Black‐bellied Sandgrouse. In Pin‐tailed Sandgrouse, mortality rate during the first week increased with increasing relative transmitter and harness weight regardless of season, and with increasing handling time during the breeding season. There were no significant differences in mortality rate between study areas, type of tag, sex or age or an effect of restraint time. These results suggest the use of lighter transmitters (< 3% of the bird's weight) and a reduction of handling time (< 20 min), particularly during the breeding season, as essential improvements in procedure to reduce the mortality risk associated with the capture, handling and tagging of these vulnerable species.  相似文献   
99.
The association between worm infections and bacterial diseases has only recently been emphasized. This study examined the effect of experimental Angiostrongylus costaricensis infection on endogenous intestinal flora of Swiss Webster mice. Eight mice aging six weeks were selected for this experiment. Four were infected with A. costaricensis and the other four were used as controls. Twenty eight days after the worm infection, all mice in both groups were sacrificed and samples of the contents of the ileum and colon were obtained and cultured for aerobic and anaerobic bacteria. In the mice infected with A. costaricensis there was a significant increase in the number of bacteria of the endogenous intestinal flora, accompanied by a decrease in the number of Peptostreptococcus spp. This alteration in the intestinal flora of mice infected by the nematode may help to understand some bacterial infections described in humans.  相似文献   
100.
The above-ground coarse wood productivity of 104 Neotropical forest plots   总被引:8,自引:1,他引:8  
The net primary production of tropical forests and its partitioning between long‐lived carbon pools (wood) and shorter‐lived pools (leaves, fine roots) are of considerable importance in the global carbon cycle. However, these terms have only been studied at a handful of field sites, and with no consistent calculation methodology. Here we calculate above‐ground coarse wood carbon productivity for 104 forest plots in lowland New World humid tropical forests, using a consistent calculation methodology that incorporates corrections for spatial variations in tree‐size distributions and wood density, and for census interval length. Mean wood density is found to be lower in more productive forests. We estimate that above‐ground coarse wood productivity varies by more than a factor of three (between 1.5 and 5.5 Mg C ha?1 a?1) across the Neotropical plots, with a mean value of 3.1 Mg C ha?1 a?1. There appear to be no obvious relationships between wood productivity and rainfall, dry season length or sunshine, but there is some hint of increased productivity at lower temperatures. There is, however, also strong evidence for a positive relationship between wood productivity and soil fertility. Fertile soils tend to become more common towards the Andes and at slightly higher than average elevations, so the apparent temperature/productivity relationship is probably not a direct one. Coarse wood productivity accounts for only a fraction of overall tropical forest net primary productivity, but the available data indicate that it is approximately proportional to total above‐ground productivity. We speculate that the large variation in wood productivity is unlikely to directly imply an equivalent variation in gross primary production. Instead a shifting balance in carbon allocation between respiration, wood carbon and fine root production seems the more likely explanation.  相似文献   
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