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91.
To improve the coupling of in situ chemical oxidation and in situ bioremediation, a systematic analysis was performed of the effect of chemical oxidation with Fenton's reagent, modified Fenton's reagent, permanganate, or persulfate, on microbial diversity and activity during 8 weeks of incubation in two diesel-contaminated soils (peat and fill). Chemical oxidant and soil type affected the microbial community diversity and biodegradation activity; however, this was only observed following treatment with Fenton's reagent and modified Fenton's reagent, and in the biotic control without oxidation. Differences in the highest overall removal efficiencies of 69 % for peat (biotic control) and 59 % for fill (Fenton's reagent) were partially explained by changes in contaminant soil properties upon oxidation. Molecular analysis of 16S rRNA and alkane monooxygenase (alkB) gene abundances indicated that oxidation with Fenton's reagent and modified Fenton's reagent negatively affected microbial abundance. However, regeneration occurred, and final relative alkB abundances were 1–2 orders of magnitude higher in chemically treated microcosms than in the biotic control. 16S rRNA gene fragment fingerprinting with DGGE and prominent band sequencing illuminated microbial community composition and diversity differences between treatments and identified a variety of phylotypes within Alpha-, Beta-, and Gammaproteobacteria. Understanding microbial community dynamics during coupled chemical oxidation and bioremediation is integral to improved biphasic field application.  相似文献   
92.
93.
Macroautophagy/autophagy is an evolutionarily conserved cellular process whose induction is regulated by the ULK1 protein kinase complex. The subunit ATG13 functions as an adaptor protein by recruiting ULK1, RB1CC1 and ATG101 to a core ULK1 complex. Furthermore, ATG13 directly binds both phospholipids and members of the Atg8 family. The central involvement of ATG13 in complex formation makes it an attractive target for autophagy regulation. Here, we analyzed known interactions of ATG13 with proteins and lipids for their potential modulation of ULK1 complex formation and autophagy induction. Targeting the ATG101-ATG13 interaction showed the strongest autophagy-inhibitory effect, whereas the inhibition of binding to ULK1 or RB1CC1 had only minor effects, emphasizing that mutations interfering with ULK1 complex assembly do not necessarily result in a blockade of autophagy. Furthermore, inhibition of ATG13 binding to phospholipids or Atg8 proteins had only mild effects on autophagy. Generally, the observed phenotypes were more severe when autophagy was induced by MTORC1/2 inhibition compared to amino acid starvation. Collectively, these data establish the interaction between ATG13 and ATG101 as a promising target in disease-settings where the inhibition of autophagy is desired.  相似文献   
94.
Diabetes mellitus induces testicular damage, increases sperm abnormalities, and impairs reproductive dysfunction due to induction of endocrine disturbance and testicular oxidative stress. This study evaluated the reproductive protective effect of ellagic acid (EA) against testicular damage and abnormalities in sperm parameters in Streptozotocin (STZ)-induced diabetic rats (T1DM) and examined some possible mechanisms of protection. Adult male rats were segregated into 5 groups (n = 12 rat/each) as control, control + EA (50 mg/kg/day), T1DM, T1DM + EA, and T1DM + EA + brusatol (an Nrf-2 inhibitor) (2 mg/twice/week). All treatments were conducted for 12 weeks, daily. EA preserved the structure of the seminiferous tubules, prevented the reduction in sperm count, motility, and viability, reduced sperm abnormalities, and downregulated testicular levels of cleaved caspase-3 and Bax in diabetic rats. In the control and diabetic rats, EA significantly increased the circulatory levels of testosterone, reduced serum levels of FSH and LH, and upregulated Bcl-2 and all steroidogenic genes (StAr, 3β-HSD1, and 11β-HSD1). Besides, it reduced levels of ROS and MDA but increased levels of GSH and MnSOD and the transactivation of Nrf2. All these biochemical alterations induced by EA were associated with increased activity and nuclear accumulation of Nrf2. However, all these effects afforded by EA were weakened in the presence of brusatol. In conclusion, EA could be an effective therapy to alleviated DM-induced reproductive toxicity and dysfunction in rats by a potent antioxidant potential mediated by the upregulation of Nrf2.  相似文献   
95.
This study reveals the expressions of Alzheimer's disease-related amyloid precursor protein, presenilin-1, and a presynaptic marker protein, synaptophysin, in the archi-, paleo- and neocerebellum during the postnatal development of the rat. The Western blot results demonstrate a gradual increase in the soluble amyloid precursor protein level in the archicerebellum during the first 3 weeks, while in the neo- and paleocerebellum the levels reach a plateau as early as the 1st week. Immunohistochemically, the protein is present in the deep part of the external granule cell layer and the internal granule cell layer in the newborn animal, while in 3-week-old animals the staining appears mainly in the perikarya and dendrites of the Purkinje cells. The level of synaptophysin increases progressively from postnatal day 7 up to 3 weeks in the archi- and paleocerebellum, and up to 6 weeks in the neocerebellum. Immunohistochemically, the amyloid precursor protein staining appears first in the inner part of the molecular layer and in the internal granule cell layer. In a 3-week-old animal, synaptophysin staining is present in all areas of the cerebellar molecular layer and in the internal granule cell layer. The presenilin-1 immunohistochemical reaction appeared equally in the archi-, paleo- and neocerebellum. Much of the staining is present in the glial cells and Purkinje cells. Less immunoreactivity is observed in the Golgi cells and granule cells. It is concluded that the postnatal expressions of soluble and membrane-bound amyloid precursor protein, synaptophysin and presenilin-1 are regulated differently during the ontogenetical development of the archi-, paleo- and neocerebellum of rat. Further, the amyloid precursor protein and presenilin-1 may be present in cells which do not degenerate in Alzheimer's disease.  相似文献   
96.
Many groups of closely related species have reticulate phylogenies. Recent genomic analyses are showing this in many insects and vertebrates, as well as in microbes and plants. In microbes, lateral gene transfer is the dominant process that spoils strictly tree‐like phylogenies, but in multicellular eukaryotes hybridization and introgression among related species is probably more important. Because many species, including the ancestors of ancient major lineages, seem to evolve rapidly in adaptive radiations, some sexual compatibility may exist among them. Introgression and reticulation can thereby affect all parts of the tree of life, not just the recent species at the tips. Our understanding of adaptive evolution, speciation, phylogenetics, and comparative biology must adapt to these mostly recent findings. Introgression has important practical implications as well, not least for the management of genetically modified organisms in pest and disease control.  相似文献   
97.
We have found that atrial natriuretic factor (ANF) has a profound effect on testicular cells in altering intracellular cyclic nucleotide levels as well as progesterone secretion. Using clonal cultured Leydig tumor cells we found that 1 X 10(-8)M ANF caused a two thousand-fold elevation in the accumulation of cellular cGMP and inhibited cAMP in treated cells by more than 90% as compared to the controls. ANF (1 X 10(-8)M) also significantly inhibited gonadotropin-stimulated accumulation of cAMP in response to bovine luteinizing hormone (bLH) or human chorionic gonadotropin (hCG). Gonadotropin-stimulated progesterone secretion was inhibited by ANF (1 X 10(-10) - 1 X 10(-9)M) in these cultured Leydig tumor cells. Approximately 50% inhibition of progesterone secretion was observed at the peptide concentration of 1 X 10(-9) M.  相似文献   
98.
Variation in susceptibility is ubiquitous in multi‐host, multi‐parasite assemblages, and can have profound implications for ecology and evolution in these systems. The extent to which susceptibility to parasites is phylogenetically conserved among hosts can be revealed by analysing diverse regional communities. We screened for haemosporidian parasites in 3983 birds representing 40 families and 523 species, spanning ~ 4500 m elevation in the tropical Andes. To quantify the influence of host phylogeny on infection status, we applied Bayesian phylogenetic multilevel models that included a suite of environmental, spatial, temporal, life history and ecological predictors. We found evidence of deeply conserved susceptibility across the avian tree; host phylogeny explained substantial variation in infection status, and results were robust to phylogenetic uncertainty. Our study suggests that susceptibility is governed, in part, by conserved, latent aspects of anti‐parasite defence. This demonstrates the importance of deep phylogeny for understanding present‐day ecological interactions.  相似文献   
99.
Antibiotics are widely used in fire blight management programs, yet there are no studies that demonstrate the evaluation of their efficacy in Mexico. Therefore, the present study was conducted to investigate the effects of the active ingredients in five commercial products (Kasumin® 2L, Agrygent Plus®, Agricultural Terramycin®, Agrimicin® 100, and Actigard®) on fire blight suppression, and fruit yield and quality of apple (Malus domestica Borkh.) cv. Golden Glory. The experiment was conducted in a commercial orchard using a completely randomized block design, with six treatments: (1) Oxytetracycline [Ox], 110 mg L−1; (2) Kasugamycin [Kas], 4.7 mL L−1; (3) Oxytetracycline + Gentamicin [Ox + Gen], 48 mg L−1 +12 mg L−1; (4) Streptomycin + Oxytetracycline [Str + Ox], 90 mg L−1 +9 mg L−1; (5) Acibenzolar-S-methyl [ASM], 70 mg L−1; and (6) Control, only water, with four replications, and three 11-year-old trees as an experimental unit. Variables of infection including flowers, shoots and fruits, yield and fruit quality were evaluated. All treatments suppressed infection in flowers, shoots, and fruits. ASM provided the highest levels of reduction of flower and shoot infection, while Kas had the least effect on the reduction of infection in these variables. The Ox + Gen treatment had the greatest suppression of fruit infection, and the best results on fruit yield and quality, followed by Ox and ASM. This is the first study conducted to evaluate the efficacy of the active ingredients of five commercial products used for the management of fire blight in apple trees in Mexico.  相似文献   
100.
Abstract: The psychostimulant drug of abuse, cocaine (benzoylecgonine methyl ester), is rapidly metabolized by cleavage of its two ester groups, to give benzoylecgonine (BE) and ecgonine methyl ester, and by N-demethylation, to give N-norcocaine (NC). The recent use of [N-methyl-11CH3]cocaine to image brain cocaine binding sites with positron emission tomography (PET) raises the question of whether PET images partially reflect the distribution and kinetics of labeled cocaine metabolites. We prepared [O-metty/-11CH3]cocaine by methylation of the sodium salt of BE with [11C]CH3l, and showed that PET baboon brain scans, as well as regional brain kinetics and plasma time-activity curves corrected for the presence of labeled metabolites, are nearly identical to those seen with [N-methyl-11CH3]cocaine. This strongly suggests that 11C metabolites do not significantly affect PET images, because the metabolite pattern is different for the two labeled forms of cocaine. In particular, nearly half the 11C in blood plasma at 30 min was [11C]CO2 when [N-methy/-11CH3]cocaine was administered, whereas [11C]CO2 was not formed from [O-methy/-11CH3]cocaine. Only a trace of [11C]NC was detected in plasma after [O-methyl-11CH3]cocaine administration. Nearly identical brain PET data were also obtained when 4′-[N-methy/-11CH3]fluorococaine and 4′-[18F]fluoro-cocaine (prepared by nucleophilic aromatic substitution from [18F]fluoride-and 4′-nitrococaine) were compared with [N-methy/-11CH3]cocaine. In vitro assays with rat brain membranes showed that cocaine and 4′-fluoroco-caine were equipotent at the dopamine reuptake site, but that 4′-fluorococaine was about 100 times more potent at the 5-hydroxytryptamine reuptake site. The studies with positron-emitting 4′-fluorococaines thus support the lack of significance of labeled metabolites or of binding to 5-hydroxytryptamine reuptake sites to PET images taken with [N-methy/-11CH3]cocaine. [11C]NC prepared by O-methylation of norbenzoylecgonine gave PET images with preferential uptake in striatum, but slower clearance from all brain regions than [O-methy/-11CH3]cocaine. [11C]BE prepared by N-methylation of norbenzoylecgonine did not show brain uptake.  相似文献   
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