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Pilot-scale constructed wetlands (CW) were constructed and operated to treat pre-treated olive mill wastewater. Pilot-scale units comprising three identical series with four pilot-scale vertical flow CWs were operated for one harvest season in a Greek olive mill plant. The pilot-scale CWs were filled with various porous media (i.e., cobble, gravel, and sand) of different gradations. Two series of pilot-scale units were planted with common reeds and the third (control) was unplanted. Mean influent concentrations were 14,120 mg/L, 2841 mg/L, 95 mg/L, 123 mg/L and 506 mg/L for COD, phenols, ortho-phosphate, ammonia and TKN, respectively. Despite the rather high influent concentrations, the performance of the CW units was very effective since it achieved removals of about 70%, 70%, 75% and 87% for COD, phenols, TKN and ortho-phosphate, respectively. COD, phenol and TKN removal seems to be significantly higher in the planted series, while ortho-phosphate removal shows no significant differences among the three series. Temperature and pollutant surface load seem to affect the removal efficiency of all pollutants. Compared to previous studies, pollutant surface loads applied here were higher (by one or two orders of magnitude). Even though high removal efficiencies were achieved, effluent pollutant concentrations remained high, thus preventing their use for irrigation or immediate disposal into the environment.  相似文献   
53.

Background

Maintenance of genome integrity is crucial for the propagation of the genetic information. Cdt1 is a major component of the pre-replicative complex, which controls once per cell cycle DNA replication. Upon DNA damage, Cdt1 is rapidly targeted for degradation. This targeting has been suggested to safeguard genomic integrity and prevent re-replication while DNA repair is in progress. Cdt1 is deregulated in tumor specimens, while its aberrant expression is linked with aneuploidy and promotes tumorigenesis in animal models. The induction of lesions in DNA is a common mechanism by which many cytotoxic anticancer agents operate, leading to cell cycle arrest and apoptosis.

Methodology/Principal Finding

In the present study we examine the ability of several anticancer drugs to target Cdt1 for degradation. We show that treatment of HeLa and HepG2 cells with MMS, Cisplatin and Doxorubicin lead to rapid proteolysis of Cdt1, whereas treatment with 5-Fluorouracil and Tamoxifen leave Cdt1 expression unaffected. Etoposide affects Cdt1 stability in HepG2 cells and not in HeLa cells. RNAi experiments suggest that Cdt1 proteolysis in response to MMS depends on the presence of the sliding clamp PCNA.

Conclusion/Significance

Our data suggest that treatment of tumor cells with commonly used chemotherapeutic agents induces differential responses with respect to Cdt1 proteolysis. Information on specific cellular targets in response to distinct anticancer chemotherapeutic drugs in different cancer cell types may contribute to the optimization of the efficacy of chemotherapy.  相似文献   
54.
The synthesis of new tricyclic fused indole and dihydroindole derivatives and preliminary results from their in vitro inhibitory activity against soluble guanylate cyclase (sGC) are presented.  相似文献   
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Exogenous administration of chondroitin sulfate (CS) is widely practiced for the treatment of osteoarthritis, although the efficacy of this treatment has not been completely established by clinical studies. A reason for the inconsistency of the results may be the quality of the CS preparations, which are commercially available as dietary supplements. In this article, we describe the development of a new method of capillary electrophoresis (CE) for the quantification of CS concentrations, screening for other glycosaminoglycan or DNA impurities and determination of hyaluronan impurities in CS raw materials, tablets, hard capsules, and liquid formulations. Analysis is performed within 12 min in bare fused silica capillaries using reversed polarity and an operating phosphate buffer of low pH. The method has high sensitivity (lower limit of quantitation [LLOQ] values of 30.0 microg/ml for CS and 5.0 microg/ml for hyaluronan), high precision, and accuracy. Analysis of 11 commercially available products showed the presence of hyaluronan impurities in most of them (up to 1.5%). CE analysis of the samples after treatment with chondroitinase ABC and ACII, which depolymerize the chains to unsaturated disaccharides, with a previously described method (Karamanos et al., J. Chromatogr. A 696 (1995) 295-305) confirmed the results of hyaluronan determination and showed that the structural characteristics (i.e., disaccharide composition) of CS are very different, showing the different species or tissue origin and possibly affecting the therapeutic outcome.  相似文献   
57.
Neutrophils are phagocytes whose principal function is to maintain anti-bacterial immunity. Neutrophils ingest and kill invading bacteria, releasing cytotoxic, chemotactic and inflammatory mediators at sites of infection. This serves to control the immediate host immune response and attract other cells, such as macrophages and dendritic cells, which are important for establishing long-term adaptive immunity. Neutrophils thus contribute to both the initiation and the maintenance of inflammation at sites of infection. Aberrant neutrophil activity is deleterious; suppressed responses can cause extreme susceptibility to infection while overactivation can lead to excessive inflammation and tissue damage. This review will focus on neutrophil regulation by granulocyte colony-stimulating factor (G-CSF), the principal cytokine controlling neutrophil development and function. The review will emphasize the molecular aspects of G-CSF-driven granulopoiesis in steady state (healthy) conditions and during demand-driven or 'emergency' conditions elicited by infection or clinical administration of G-CSF. Understanding the molecular control of granulopoiesis will aid in the development of new approaches designed to treat disorders of neutrophil production and function.  相似文献   
58.
The cancer microenvironment and the interactions between cancer and surrounding tissue cells are thought to play a pivotal role in tumor development and progression. Glycosaminoglycans (GAGs)/proteoglycans (PGs) are major constituents of the extracellular matrix, the composition of which may affect various cellular functions. In the present study, the effects of GAGs on the proliferation of HT29, SW1116, and HCT116 human colon cancer cell lines were examined using exogenously added GAGs, an inhibitor of endogenous GAG sulfation and specific glycosidase digestions. Our results demonstrate that colon cancer cell growth was exclusively stimulated by exogenously added heparin and insensitive to endogenous GAGs/PGs production, in a sulfation pattern-related manner. Treatment of the tested cell lines with the FGF-2 neutralizing antibody showed that the stimulatory effect of heparin on the cells' growth was not FGF-2-dependent. Responsiveness of colon cancer cell lines to exogenous heparin/heparan sulfate may play a role in their growth and metastasis.  相似文献   
59.
The Jamaican boa (Epicrates subflavus; also called Yellow boa) is an endemic species whose natural populations greatly and constantly declined since the late 19th century, mainly because of predation by introduced species, human persecution, and habitat destruction. In-situ conservation of the Jamaican boa is seriously hindered by the lack of information on demographic and ecological parameters as well as by a poor understanding of the population structure and species distribution in the wild. Here, using nine nuclear microsatellite loci and a fragment of the mitochondrial cytochrome b gene from 87 wild-born individuals, we present the first molecular genetic analyses focusing on the diversity and structure of the natural populations of the Jamaican boa. A model-based clustering analysis of multilocus microsatellite genotypes identifies three groups that are also significantly differentiated on the basis of F-statistics. Similarly, haplotypic network reconstruction methods applied on the cytochrome b haplotypes isolated here identify two well-differentiated haplogroups separated by four to six fixed mutations. Bayesian and metaGA analyses of the mitochondrial data set combined with sequences from other Boidae species indicate that rooting of the haplotypic network occurs most likely between the two defined haplogroups. Both analyses (based on nuclear and mitochondrial markers) underline an Eastern vs. (Western + Central) pattern of differentiation in agreement with geological data and patterns of differentiation uncovered in other vertebrate and invertebrate Jamaican species. Our results provide important insights for improving management of ex-situ captive populations and for guiding the development of proper in-situ species survival and habitat management plans for this spectacular, yet poorly known and vulnerable, snake.  相似文献   
60.
The basally located actin cytoskeleton has been demonstratedpreviously to regulate Clsecretion from intestinal epithelia via its effects on theNa+-K+-2Clcotransporter (NKCC1). In nontransporting epithelia, inhibition ofmyosin light chain kinase (MLCK) prevents cell-shrinkage-induced activation of NKCC1. The aim of this study was to investigate the roleof myosin in the regulation of secretagogue-stimulated Cl secretion in intestinalepithelia. The human intestinal epithelial cell line T84 was used forthese studies. Prevention of myosin light chain phosphorylation withthe MLCK inhibitor ML-9 or ML-7 and inhibition of myosin ATPase withbutanedione monoxime (BDM) attenuated cAMP but notCa2+-mediatedCl secretion. Both ML-9 andBDM diminished cAMP activation of NKCC1. Neither apicalCl channel activity,basolateral K+ channel activity,norNa+-K+-ATPasewere affected by these agents. Cytochalasin D prevented suchattenuation. cAMP-induced rearrangement of basal actin microfilaments was prevented by both ML-9 and BDM. The phosphorylation of mosin lightchain and subsequent contraction of basal actin-myosin bundles arecrucial to the cAMP-driven activation of NKCC1 and subsequent apicalCl efflux.

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