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41.
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Michelini L Meggio F La Rocca N Ferro S Ghisi R 《International journal of phytoremediation》2012,14(4):388-402
The application of manure to fertilize arable lands is one of the major means through which veterinary sulfonamides (SAs) enter the environment. Little is known about the capacity of woody plants to phytoremediate this class of antibiotics. To this purpose we performed preliminary studies to evaluate Salix fragilis L. response to sulfadimethoxine (SDM) by investigating both its ability to absorb and tolerate doses of SDM found in fresh faeces of treated calves. Forty cuttings were exposed to either 0, 0.5, 1, or 2 mM of SDM for one month. Decreases in photosynthetic electron transport rate and net CO2 assimilation after 25 days for the higher SDM concentrations were noticed. Moreover, alterations in root morphology of treated plants were observed and further investigated through electron microscopy. However, collected data revealed high root accumulation potential. These preliminary results are promising as they demonstrate that Salix fragilis L. can both absorb and tolerate high concentrations of SAs. 相似文献
43.
Sunlight is a key environmental factor in almost all ecosystems, and it is necessary for many physiological functions. Many vertebrates require ultraviolet (UV) radiation to perform different physiological processes. Artificial light is used to supplement UV in captive animals, through appropriate photoperiods and UV wavelengths. Previous studies reported that repeated exposure to artificial UV radiation may cause damage to the immune system. Taking into account the importance of UV effects and the serum complement system, the relationship between them was investigated. The study lasted 90 days and was carried out in plastic chambers. Ninety six broad‐snouted caiman (C. latirostris) were assigned to four treatment groups with two replicates each: total darkness (TD), 8 hr per day (8 hr) and 16 hr per day (16 hr) of artificial UV/visible light exposure, and normal photoperiod of natural light (NP). Snout–vent length was measured to determine animal growth. Hemolytic assays were performed to evaluate the effects of artificial UV/visible light, TD, and NP on the serum complement system. Results showed that animals grew more in the NP group. The capacity of C. latirostris serum to hemolyze sheep red blood cells was higher in the NP group than when they are maintained in constant light–dark cycles (8 and 16 hr) or in TD. These data demonstrate that artificial UV should be considered as a potential hazard for captive crocodilians if it is not properly managed, and this should be taken into account in the general design of facilities for reptilian husbandry. Zoo Biol 31:523‐533, 2012. © 2011 Wiley Periodicals, Inc. 相似文献
44.
Alberto M. Martelli Lucia Manzoli Silvia Rubbini Anna Maria Billi Renato Bareggi Lucio Cocco 《Biology of the cell / under the auspices of the European Cell Biology Organization》1995,83(1):15-22
Summary— Using two-dimensional polyacrylamide gels stained with Coomassie blue we have studied the protein composition of the nuclear matrix obtained from mouse erythroleukemic nuclei kept at O°C throughout the isolation procedure to prepare the high ionic strength resistant fraction (control matrix) or stabilized in vitro or in vivo by different procedures prior to subfractionation (ie 37°C incubation of isolated nuclei; sodium tetrathionate exposure of purified nuclei; heat shock of intact cells). When the matrix obtained from 37°C incubated nuclei was compared with the control matrix, striking differences in the polypeptide pattern were seen if the protein was obtained in both cases from an equivalent number of nuclei. On the other hand, if the same amount of protein for both the samples was applied to the gels the differences were less evident. Sodium tetrathionate stabilization of isolated nuclei and heat shock of intact cells produced a matrix protein pattern that was very similar and differed from that of the in vitro heat-exposed matrix. Using specific polyclonal antisera, we demonstrate that nucleolar proteins B23/numatrin and C23/nucleolin were very abundant in the matrix obtained from chemically-treated nuclei or in vivo heat-stabilized nuclei but were recovered in very small amounts (B23) or completely absent (C23) in the matrix prepared from nuclei heated to 37°C in vitro. Differences were seen also in the recovery of nuclear lamins, and especially lamin B, that was poorly represented in the sodium tetrathionate-stabilized matrix. The results demonstrate that in mouse erythroleukemia cells the increased recovery of nuclear matrix protein that is seen after in vitro heating of isolated nuclei is predominantly due to an additional recovery of the same types of polypeptides that are detected also in the absence of such a treatment. The data also indicate that in vivo heat shock of intact cells produces a nuclear matrix protein pattern that is more similar to the pattern seen after stabilization of purified nuclei with sodium tetrathionate and differs significantly from that obtained by exposing nuclei to 37°C in vitro, unlike to that what previous reports have indicated. 相似文献
45.
Identification of mutations that decrease the stability of a fragment of Saccharomyces cerevisiae chromosome III lacking efficient replicators 总被引:1,自引:0,他引:1
Theis JF Dershowitz A Irene C Maciariello C Tobin ML Liberi G Tabrizifard S Korus M Fabiani L Newlon CS 《Genetics》2007,177(3):1445-1458
Eukaryotic chromosomes are duplicated during S phase and transmitted to progeny during mitosis with high fidelity. Chromosome duplication is controlled at the level of replication initiation, which occurs at cis-acting replicator sequences that are spaced at intervals of approximately 40 kb along the chromosomes of the budding yeast Saccharomyces cerevisiae. Surprisingly, we found that derivatives of yeast chromosome III that lack known replicators were replicated and segregated properly in at least 96% of cell divisions. To gain insight into the mechanisms that maintain these "originless" chromosome fragments, we screened for mutants defective in the maintenance of an "originless" chromosome fragment, but proficient in the maintenance of the same fragment that carries its normal complement of replicators (originless fragment maintenance mutants, or ofm). We show that three of these Ofm mutations appear to disrupt different processes involved in chromosome transmission. The OFM1-1 mutant seems to disrupt an alternative initiation mechanism, and the ofm6 mutant appears to be defective in replication fork progression. ofm14 is an allele of RAD9, which is required for the activation of the DNA damage checkpoint, suggesting that this checkpoint plays a key role in the maintenance of the "originless" fragment. 相似文献
46.
Dipineto L Manna L Baiano A Gala M Fioretti A Gravino AE Menna LF 《Journal of wildlife diseases》2007,43(3):518-520
Skin, lymph node (popliteal), and bone marrow samples were collected from 50 red foxes (Vulpes vulpes) from May 2004 to May 2005 in southern Italy. Samples were tested for Leishmania infantum by polymerase chain reaction (PCR). The parasite was detected by PCR from 20 of 50 (40%) fox carcasses. All 20 positive cases were PCR-positive from lymph node and bone marrow samples, whereas 17 of 20 positive cases were PCR-positive from skin samples. Infection status was not related to age or sex. This is the first report of leishmaniasis in red foxes in Italy based on PCR results, and these results reinforce the assumption that this wild canid can serve as a reservoir for Leishmania. 相似文献
47.
Graziella Hanna Pereira Aline Queiroz Santos Miriam Park Patricia Rady Muller Soraia Padua Raquel Ferrari Marchesi Vera Lucia Aldred 《Mycopathologia》2010,170(4):259-261
Paracoccidioides brasiliensis rarely shows bone marrow involvement and its response to treatment with itraconazole in children needs further assessment. We describe here a child with a juvenile disseminated form of paracoccidioidomycosis, which showed reticuloendothelial system involvement and the presence of Paracoccidioides brasiliensis in the bone marrow. The patient showed an effective and rapid response to itraconazole therapy. 相似文献
48.
Giovanni Gherardi Lucia De Florio Giulia Lorino Laura Fico & Giordano Dicuonzo 《FEMS immunology and medical microbiology》2009,55(1):62-67
One hundred macrolide-resistant staphylococcal isolates from clinically relevant infections in Italy during a 19-month period were studied. Four distinct resistance phenotypes were observed using the triple-disk induction test (erythromycin, clindamycin, telithromycin): the cMLSB phenotype (24 isolates); the iMLSB phenotype (41 isolates); the MS phenotype (three isolates); and the iMTS phenotype (erythromycin-induced telithromycin resistance) (32 isolates). ermC and ermA genes predominated within erythromycin-resistant Staphylococcus aureus isolates with iMLSB phenotype and cMLSB phenotype, respectively. Among erythromycin-resistant CoNS isolates, half of the strains showed the iMTS or MS/ msrA association, and ermC gene predominated among isolates with MLSB phenotype. By pulsed-field gel electrophoresis, high genetic heterogeneity was observed among the isolates studied. Both independent acquisition of macrolide resistance genes and spread of specific resistant clones were observed. Association between certain clonal types and specific types of infection could be detected. To our knowledge, this is the first report on characterization of erythromycin-resistant staphylococci in Italy. 相似文献
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50.
We have surveyed 18 natural populations of Drosophila melanogaster for the presence of 23 retrotransposon-gene-association alleles (i.e., the presence of an LTR retrotransposon sequence in or within 1,000 bp of a gene) recently identified in the sequenced D. melanogaster genome. The identified associations were detected only in the D. melanogaster populations. The majority (61%) of the identified retrotransposon-gene associations were present only in the sequenced strain in which they were first identified. Thirty percent of the associations were detected in at least one of the natural populations, and 9% of the associations were detected in all of the D. melanogaster populations surveyed. Sequence analysis of an association allele present in all populations indicates that selection is a significant factor in the spread and/or maintenance of at least some of retroelement-gene associations in D. melanogaster. 相似文献