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1.
Fish are often used as models for studies investigating the ability of xenobiotics to induce oxidative stress, though age or developmental stage of the individuals studied has been given little attention. Oxidative stress in other organisms is associated with aging as well as with periods of rapid growth, which occurs in young brown trout. We measured protein carbonyls, 20S proteosome activity and glutathione (GSH) levels in farmed Salmo trutta in four different age groups from 5 months to 3 years. We found an increase in protein carbonyls and a decrease in 20S proteosome activity in both brain and liver tissues of the fish with increasing size and age. Total GSH levels in liver tissue declined as fish aged and the GSSG:GSH ratio increased. Five month and 1 year old trout were treated with paraquat (PQ) to induce oxidative stress. Five month old fish showed no changes in the measured parameters while 1 year old fish had both an increase in protein carbonylation in liver tissue and a decrease in 20S proteosome activity in brain tissue. These results indicate that oxidative stress biomarkers are affected by age or rapid growth in brown trout, and that individuals of different ages respond differently to oxidative stress induced by PQ.  相似文献   

2.
Herring spermatozoa exhibit higher activity of malic enzyme (ME) than Atlantic salmon (Salmo salar), brown trout (Salmo trutta), carp (Cyprinus carpio) and African catfish (Clarias gariepinus) spermatozoa. Two molecular forms of ME are present in herring spermatozoa: an NAD-preferring malic enzyme with very high activity and an NADP-specific malic enzyme with much lower activity (ratio about 33:1). NAD-preferring ME was purified by chromatography on DEAE-Sepharose, Red Agarose and Sephadex G-200 to a specific activity of 36 μmol/min/mg protein and NADP-specific ME on DEAE-Sepharose and 2′5′-ADP Sepharose. The molecular mass for NAD-preferring and NADP-specific ME determined by SDS-PAGE was equal to 61 and 64 kDa, respectively. High activity of ME suggests adaptation of herring spermatozoa to metabolism at high oxygen tension for herring spawn.  相似文献   

3.
Submerged conidia and blastospores of the entomopathogenic fungus Isaria fumosorosea are produced in several liquid culture media. However, yields and the ecological fitness of these propagules vary according to culture media composition. In most culture media, hyphae, blastospores and submerged conidia are white but we found that in some media they develop a brown pigmentation. A dark pigment was extracted from brown-pigmented propagules and analyzed by IR spectroscopy. Adsorption bands coincided to those characteristics of melanins.Hadamard's matrices were employed in order to increase submerged conidia yields and brown pigmentation of fungal propagules. Media containing 20–30 mg/l of FeSO4·7H2O and 6–12 mg/l of CuSO4·5H2O allowed reaching the highest pigmentation (9 in a hedonic scale). A maximal concentration of submerged conidia of 1.0 (±1.2) × 1012 cell/l was achieved after 120 h of liquid culture in a improved culture medium, containing 25 ml/l of Polyethylene glycol (MW 200), substance which enhanced submerged conidia production, reducing free mycelia or mycelial pellets formation. In the improved medium, it was estimated that more than 60% of produced biomass corresponded to submerged conidia and blastospores, while in other media, mycelia were the main product (80–97%).  相似文献   

4.
Despite being genetically very closely related, the marble trout Salmo marmoratus and the brown trout Salmo trutta exhibit marked phenotypic differences, particularly with regard to skin pigmentation. Histological analysis of skin from the head and gill cover of differently aged individuals of the two species was carried out in order to characterize differences in skin structure. The basic structure of skin of the individuals studied corresponded with that described for other salmonids, though the head epidermis was somewhat thicker in S. marmoratus than in S. trutta, thickening with age in both species. Numerous secretory goblet cells and sporadic secretory sacciform cells were observed in the upper and middle part of the epidermis in both species. Melanophores were present in both species only in the dermis, and were bigger in S. marmoratus and present at lower average density than in S. trutta, and more or less constant across all age classes. In adult S. marmoratus with fully established marble pigmentation, light areas at low density with small (i.e. aggregated) melanophores were present, while in S. trutta melanophores were more uniformly distributed.  相似文献   

5.
Phytoplankton bloom is one of the most serious threats to water resource, and remains a global challenge in environmental management. Real-time monitoring and forecasting the dynamics of phytoplankton and early warning the risks are critical steps in an effective environmental management. Automated online sondes have been widely used for in situ real-time monitoring of water quality due to their high reliability and low cost. However, the knowledge of using real-time data from those sondes to forecast phytoplankton blooms has been seldom addressed. Here we present an integrated system for real-time observation, early warning and forecasting of phytoplankton blooms by integrating automated online sondes and the ecological model. Specifically, based on the high-frequency data from automated online sondes in Xiangxi Bay of Three Gorges Reservoir, we successfully developed 1–4 days ahead forecasting models for chlorophyll a (chl a) concentration with hybrid evolutionary algorithms (HEAs). With the predicted concentration of chl a, we achieved a high precision in 1–7 days ahead early warning of good (chl a < 25 μg/L) and eutrophic (chl a 8–25 μg/L) conditions; however only achieved an acceptable precision in 1–2 days ahead early warning of hypertrophic condition (chl a  25 μg/L). Our study shows that the optimized HEAs achieved an acceptable performance in real-time short-term forecasting and early warning of phytoplankton blooms with the data from the automated in situ sondes. This system provides an efficient way in real-time monitoring and early warning of phytoplankton blooms, and may have a wide application in eutrophication monitoring and management.  相似文献   

6.
The association of molecular variants with phenotypic variation is a main issue in biology, often tackled with genome-wide association studies (GWAS). GWAS are challenging, with increasing, but still limited, use in evolutionary biology. We used redundancy analysis (RDA) as a complimentary ordination approach to single- and multitrait GWAS to explore the molecular basis of pigmentation variation in brown trout (Salmo trutta) belonging to wild populations impacted by hatchery fish. Based on 75,684 single nucleotide polymorphic (SNP) markers, RDA, single- and multitrait GWAS allowed the extraction of 337 independent colour patterning loci (CPLs) associated with trout pigmentation traits, such as the number of red and black spots on flanks. Collectively, these CPLs (i) mapped onto 35 out of 40 brown trout linkage groups indicating a polygenic genomic architecture of pigmentation, (ii) were found to be associated with 218 candidate genes, including 197 genes formerly mentioned in the literature associated to skin pigmentation, skin patterning, differentiation or structure notably in a close relative, the rainbow trout (Onchorhynchus mykiss), and (iii) related to functions relevant to pigmentation variation (e.g., calcium- and ion-binding, cell adhesion). Annotated CPLs include genes with well-known pigmentation effects (e.g., PMEL, SLC45A2, SOX10), but also markers associated with genes formerly found expressed in rainbow or brown trout skins. RDA was also shown to be useful to investigate management issues, especially the dynamics of trout pigmentation submitted to several generations of hatchery introgression.  相似文献   

7.
Several mutants of the silkworm Bombyx mori show body color variation at the larval and adult stages. The Wild wing spot (Ws) mutant exhibits a phenotype in which the moth has a spot on the apex of the forewing. In this study, we investigated this trait to elucidate the molecular mechanism underlying the color pattern. Microscopy of the black spot of Ws mutants showed that the pigment emerges in the scales of the wing, and accumulation of the pigment becomes strong just before eclosion. We next examined the relationship between the black spot of the Ws mutant and melanin. The spectrophotometry using alkaline extracts from the black spot in the wing showed the highest absorption intensity at 405 nm, which is the absorbance wavelength of melanin. Moreover, inhibition assays for enzymes implicated in melanin synthesis using 3-iodo-l-tyrosine (a tyrosine hydroxylase inhibitor) and L-α-methyl-DOPA (a dopa decarboxylase inhibitor) revealed that treatment with each inhibitor disrupted the pigmentation of the wing of the Ws mutant. On the basis of these results, we analyzed the expression pattern of five genes involved in melanin formation, and found that the expression levels of yellow and laccase2 were increased just before pigmentation, whereas those of DDC, tan, and TH were increased when the apex of the wing turned black. These results showed that melanin pigmentation gives rise to the black spot on the wing.  相似文献   

8.
《Mammalian Biology》2014,79(4):268-276
The Balkans are one of the last large refugia for brown bear (Ursus arctos) populations in Europe, and Bulgaria, in particular, contains relatively large areas of suitable brown bear habitat and a potential population of more than 600 individuals. Despite this, the majority of brown bear research remains focused on bear populations in Central and Western Europe. We provide the first assessment of genetic population structure of brown bears in Bulgaria by analysing tissue samples (n = 16) as well as samples collected with noninvasive genetic methods, including hair and faecal samples (n = 189 and n = 163, respectively). Sequence analysis of a 248 base pair fragment of the mitochondrial control region showed that two highly divergent mitochondrial European brown bear lineages form a contact zone in central Bulgaria. Furthermore, the analysis of 13 polymorphic microsatellite markers identified 136 individuals and found substantial genetic variability (He = 0.74; NA = 8.9). The combination of both genetic markers revealed the presence of weak genetic substructure in the study area with considerable degrees of genetic admixture and the likely presence of migration corridors between the two subpopulation in the Rhodope Mountains and Stara Planina as evidenced from the genetic detection of two male long-distance dispersers. A detailed assessment from densely collected samples in the Rhodope Mountains resulted in a population size estimate of 315 (95% CI = 206–334) individuals, indicating that not all available habitat is presently occupied by bears in this region. Efficient management plans should focus on preserving connectivity of suitable habitats in order to maintain gene flow between the two Bulgarian brown bear subpopulations.  相似文献   

9.
Background: Telomeres help maintain chromosomal structure and may influence tumorigenesis. We examined the association between telomere length and skin cancer in a clinic-based case-control study of 198 melanoma cases, 136 squamous cell carcinoma (SCC) cases, 185 basal cell carcinoma (BCC) cases, and 372 healthy controls. Methods: Cases were histologically confirmed patients treated at the Moffitt Cancer Center and University of South Florida Dermatology Clinic in Tampa, FL. Controls self-reported no history of cancer and underwent a skin cancer screening exam at study enrollment to rule out the presence of skin cancer. Quantitative real time PCR was used to measure telomere length in peripheral blood samples. Results: Melanoma patients had longer telomeres than controls (odds ratio (OR) = 3.75; 95% confidence interval (CI): 2.02–6.94 for highest versus lowest tertile) (P for trend = <0.0001). In contrast, longer telomere length was significantly inversely associated with SCC (OR = 0.01; 95% CI: 0.00–0.05 for highest versus lowest tertile) (P for trend = <0.0001) and BCC (OR = 0.10; 95% CI: 0.06–0.19 for highest versus lowest tertile) (P for trend = <0.0001). Conclusion: Telomere length may be involved in the development of skin cancer, although the effect on cancer risk differs for melanoma and non-melanoma carcinomas. Our findings suggest that long telomere length is positively associated with melanoma while inversely associated with SCC and BCC.  相似文献   

10.
《农业工程》2014,34(3):154-159
The distribution and size fractions of chlorophyll a (Chl a) concentration in the eastern equatorial Pacific Ocean in boreal autumn were investigated during October and November, 2011. Environmental factors, including hydrology and nutrients, that might affect the distribution and size composition were analyzed. A total of 18 stations including 11 CTD stations and 7 navigation stations were selected which stretch from the northwest coast of South America to the area of the central Pacific Ocean south of the Hawaiian Islands (2.77°S–13.02°N, 84.11–154.02°W). The studied area can be divided into two transects: the 6°N transect (124–148°W) and the154°W transect (10–13°N). Results showed that the surface Chl a concentration was higher in the east near the northwest coast of South America (>0.200 mg/m3) and lower in the west (0.100–0.200 mg/m3), and it presented a highly significant negative correlation with sea surface temperature (p < 0.001). There were some differences between the sectional distribution of Chl a concentration between the 6°N and 154°W transects. The high values of Chl a concentration occurred near the surface along the 6°N transect (0–75 m), while they were relatively deeper along the 154°W transect (50–100 m). Iron might be the factor that limited the growth of phytoplankton in the eastern equatorial Pacific Ocean. Picophytoplankton (Pico) was the dominant taxa in the surveyed area, particularly in the waters along the two transects (>70% of total Chl a). The Pico to total Chl a ratio was higher in the upper layer (>70%) than in the deeper layer.  相似文献   

11.
Herein, we report the synthesis and screening of cyano substituted biaryl analogs 5(am) as Peptide deformylase (PDF) enzyme inhibitors. The compounds 5a (IC50 value = 13.16 μM), 5d (IC50 value = 15.66 μM) and 5j (IC50 value = 19.16 μM) had shown good PDF inhibition activity. The compounds 5a (MIC range = 11.00–15.83 μg/mL), 5b (MIC range = 23.75–28.50 μg/mL) and 5j (MIC range = 7.66–16.91 μg/mL) had also shown potent antibacterial activity when compared with ciprofloxacin (MIC range = 25–50 μg/mL). Thus, the active derivatives were not only potent PDF inhibitors but also efficient antibacterial agents. In order to gain more insight on the binding mode of the compounds with PDF, the synthesized compounds 5(am) were docked against PDF enzyme of Escherichia coli and compounds exhibited good binding properties. In silico ADME properties of synthesized compounds were also analyzed and showed potential to develop as good oral drug candidates.  相似文献   

12.
Eight dimethylaminomethyl-substituted curcumin derivatives were designed and synthesized. The antioxidant test revealed that the synthesized compounds had higher free radical scavenging activity towards both 2,2-diphenyl-1-picrylhydrazyl free radicals (DPPH) (IC50 1.5–29.9 μM) and galvinoxyl radicals (IC50 4.9–41.1 μM) than the lead compound curcumin. Besides, compound 3a could effectively inhibit the Aβ self-aggregation in vitro. Investigated in phosphate-buffered solutions (pH = 7.4) in the presence or absence of 0.1% FBS 3a showed a good stability while curcumin did not. Furthermore, 3a showed a good lipophilicity (log P = 3.48), suggesting a potential ability to penetrate the blood–brain-barrier. The aqueous solubility of the hydrochloride salt of 3a (16.7 mg/mL) has also been significantly improved as compared with curcumin (<0.1 mg/mL).  相似文献   

13.
A new series of 6-(4′-aryloxy-phenyl)vinyl-1,2,4-trioxanes 10ad, 11ad, and 12ad have been synthesized and evaluated for their antimalarial activity against multidrug-resistant Plasmodium yoelii in Swiss mice by oral route. Trioxanes 10b and 10c, the two most active compounds of the series, provided 100% protection to the infected mice at 48 mg/kg × 4 days. Clinically useful drug β-arteether provided 100% and 20% protection at 48 mg/kg × 4 days and 24 mg/kg × 4 days, respectively, in this model.  相似文献   

14.
Seven novel diamidino 2,5-bis(aryl)thiazoles (5ag) were synthesized and evaluated against Trypanosoma brucei rhodensiense (T. b. r.) and Plasmodium falciparum (P. f.). The diamidines were obtained directly from the corresponding bis-nitriles (4ag) by the action of lithium bis(trimethylsilyl)amide. The bis-nitriles 4af were synthesized in four steps starting with the Stille coupling of 2-tributyltinthiazole with the appropriate cyanoaryl halide. The bis-nitrile 5g was obtained by the palladium facilitated coupling of the mixed tin-silyl reagent 2-trimethylsilyl-5-trimethyltinthiazole with 2-bromo-5-cyanopyridine. The amidoxime potential prodrugs 6ae, 6g were obtained by the reaction of hydroxylamine with the bis-nitriles. O-Methylation of the amidoximes gave the corresponding N-methoxyamidines 7ac, 7e, 7g. The diamidines showed strong DNA binding affinity as reflected by ΔTm measurements. Four of the diamidines 5a, 5b, 5d and 5e were highly active in vitro against P. f. giving IC50 values between 1.1 and 2.5 nM. The same four diamidines showed IC50 values between 4 and 6 nM against T. b. r. The selectivity indices ranged from 233 to 9175. One diamidine 5a produced one of four cures at an ip dose of 4 × 5 mg/kg in the STIB900 mouse model for acute African trypanosomiasis. The amidoxime and N-methoxyamidine of 5a were the only produgs to provide cures (1/4 cures) in the same mouse model on oral dosage at 4 × 25 mg/kg.  相似文献   

15.
Black tomatoes have a unique color and higher lycopene content than typical red tomatoes. Here, black tomatoes were investigated how maturation stage and storage temperature affected carotenoid and chlorophyll accumulation. Immature fruits were firmer than mature fruits, but failed to develop their distinctive color and contained less lycopene when stored at 8 °C. Hunter a* values of black tomatoes increased with storage temperature and duration; storage of immature fruits at high temperature favored lycopene accumulation. Chlorophyll levels of black tomatoes declined during storage, but differences between mature and immature tomatoes stored at 12 °C were minimal. β-Carotene levels of black tomatoes increased during early storage, but rapidly declined beginning 13 d post-harvest. The highest lycopene and chlorophyll levels were observed in mature black tomatoes stored at 12 °C for 13 d; these conditions also yielded the best quality fruit. Thus, the unique pigmentation properties of black tomatoes can be precisely controlled by standardizing storage conditions.  相似文献   

16.
A new convenient method for preparation of 2-aroyl-[1]benzopyrano[4,3-c]pyrazol-4(1H)-one derivatives 5bg and coumarin containing hydrazide-hydrazone analogues 4ae was presented. The antimycobacterial activity against reference strain Mycobacterium tuberculosis H37Rv and cytotoxicity against the human embryonic kidney cell line HEK-293 were tested in vitro. All compounds demonstrated significant minimum inhibitory concentrations (MIC) ranging 0.28–1.69 μM, which were comparable to those of isoniazid. The cytotoxicity (IC50 > 200 µM) to the “normal cell” model HEK-293T exhibited by 2-aroyl-[1]benzopyrano[4,3-c]pyrazol-4(1H)-one derivatives 5be, was noticeably milder compared to that of their hydrazone analogues 4ae (IC50 33–403 µM). Molecular docking studies on compounds 4ae and 5bg were also carried out to investigate their binding to the 2-trans-enoyl-ACP reductase (InhA) enzyme involved in M. tuberculosis cell wall biogenesis. The binding model suggested one or more hydrogen bonding and/or arene-H or arene-arene interactions between hydrazones or pyrazole-fused coumarin derivatives and InhA enzyme for all synthesized compounds.  相似文献   

17.
Hyperpolarization enhances the intensity of the NMR signals of a molecule, whose in vivo metabolic fate can be monitored by MRI with higher sensitivity. SABRE is a hyperpolarization technique that could potentially be used to image nitric oxide (NO) production in vivo. This would be very important, because NO dysregulation is involved in several pathologies, including cardiovascular ones. The nitric oxide synthase (NOS) pathway leads to NO production via conversion of l-arginine into l-citrulline. NO is a free radical gas with a short half-life in vivo (≈5 s), therefore direct NO quantification is challenging. An indirect method – based on quantifying conversion of an l-Arg- to l-Cit-derivative by 1H NMR spectroscopy – is herein proposed. A small library of pyridyl containing l-Arg derivatives was designed and synthesised. In vitro tests showed that compounds 4aj and 11ac were better or equivalent substrates for the eNOS enzyme (NO2? production = 19–46 μM) than native l-Arg (NO2? production = 25 μM). Enzymatic conversion of l-Arg to l-Cit derivatives could be monitored by 1H NMR. The maximum hyperpolarization achieved by SABRE reached 870-fold NMR signal enhancement, which opens up exciting future perspectives of using these molecules as hyperpolarized MRI tracers in vivo.  相似文献   

18.
Four series of phenylpyrimidine-carboxamide derivatives bearing 1H-pyrrolo[2,3-b]pyridine moiety (14ae, 15ag, 16ae and 17ag) were designed, synthesized and evaluated for the IC50 values against three cancer cell lines (A549, PC-3 and MCF-7). Four selected compounds (15e, 16ab and 17a) were further evaluated for the activity against c-Met kinase, HepG2 and Hela cell lines. Most of the compounds showed excellent cytotoxicity activity and selectivity with the IC50 valuables in single-digit μM to nanomole range. Eleven of them are equal to more active than positive control Foretinib against one or more cell lines. The most promising compound 15e showed superior activity to Foretinib against A549, PC-3 and MCF-7 cell lines, with the IC50 values of 0.14 ± 0.08 μM, 0.24 ± 0.07 μM and 0.02 ± 0.01 μM, which were 4.6, 1.6 and 473.5 times more active than Foretinib (0.64 ± 0.26 μM, 0.39 ± 0.11 μM, 9.47 ± 0.22 μM), respectively. Structure–activity relationships (SARs) and docking studies indicated that the replacement of phenylpicolinamide scaffold with phenylpyrimidine fragment of the target compounds was benefit for the activity. What’s more, the introduction of fluoro atom to the aminophenoxy part played no significant impact on the activity and any substituent group on aryl group is unfavourable for the activity.  相似文献   

19.
Three series of novel heterocyclic compounds (3a3g, 4a4g and 5a5g) containing benzenesulfonamide moiety and incorporating a 1,2,4-triazole ring, have been synthesized and investigated as inhibitors against four isomers of the α-class carbonic anhydrases (CAs, EC 4.2.1.1), comprising hCAs I and II (cytosolic, ubiquitous isozymes) and hCAs IX and XII (transmembrane, tumor associated isozymes). Against the human isozymes hCA I and II, compounds of two series (3a3g and 4a4g) showed Ki values in the range of 84–868 nM and 5.6–390 nM, respectively whereas compounds of series 5a5g were found to be poor inhibitors (Ki values exceeding 10,000 nM in some cases). Against hCA IX and XII, all the tested compounds exhibited excellent to moderate inhibitory potential with Ki values in the range of 2.8–431 nM and 1.3–63 nM, respectively. Compounds 3d, 3f and 4f exhibited excellent inhibitory potential against all of the four isozymes hCA I, II, IX and XII, even better than the standard drug acetazolamide (AZA) whereas compound of the series 5a5g were comparatively less potent but more selective towards hCA IX and XII.  相似文献   

20.
A new series of 5-(1-aryl-3-methyl-1H-pyrazol-4-yl)-1H-tetrazole derivatives (4am) and their precursor 1-aryl-3-methyl-1H-pyrazole-4-carbonitriles (3am) were synthesized and evaluated as antileishmanials against Leishmania braziliensis and Leishmania amazonensis promastigotes in vitro. In parallel, the cytotoxicity of these compounds was evaluated on the RAW 264.7 cell line. The results showed that among the assayed compounds the substituted 3-chlorophenyl (4a) (IC50/24 h = 15 ± 0.14 μM) and 3,4-dichlorophenyl tetrazoles (4d) (IC50/24 h = 26 ± 0.09 μM) were the most potent against L. braziliensis promastigotes, as compared the reference drug pentamidine, which presented IC50 = 13 ± 0.04 μM. In addition, 4a and 4d derivatives were less cytotoxic than pentamidine. However, these tetrazole derivatives (4) and pyrazole-4-carbonitriles precursors (3) differ against each of the tested species and were more effective against L.braziliensis than on L. amazonensis.  相似文献   

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