Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 17 de 17
Filter
Add more filters










Publication year range
1.
PLoS One ; 18(5): e0278616, 2023.
Article in English | MEDLINE | ID: mdl-37130086

ABSTRACT

The antifungal effects of Citrullus colocynthis extract (Hexane, chloroform, methanol, and water) were tested in vitro on Fusarium oxysporum f. sp. lycopersici (Sacc.) W. C. Snyder & H. N. Hans (FOL), the causal agent of Fusarium wilt. Of these, methanol and water extract at 10% showed the highest inhibition of mycelial growth of FOL by 12.32 and 23.61 mm respectively. The antifungal compounds were identified through Fourier transform infrared (FT-IR) spectroscopy and gas chromatography-mass spectroscopy (GC-MS). The methanol extract was compatible with the biocontrol agent Trichoderma viride. The antagonistic fungi were mass-cultured under laboratory conditions using sorghum seeds. Both T. viride and C. colocynthis methanol extract was also tested alone and together against FOL under both in vitro and in vivo conditions. The combination of T. viride and C. colocynthis showed the highest percentage of antifungal activity (82.92%) against FOL under in vitro conditions. This study revealed that induced systemic resistance (ISR) in enhancing the disease resistance in tomato plants against Fusarium wilt disease. The combined treatment of T. viride and C. colocynthis significantly reduced the disease incidence and index by 21.92 and 27.02% in greenhouse conditions, respectively. Further, the induction of defense enzymes, such as peroxidase (PO), polyphenol oxidase (PPO), ß-1,3-glucanase, and chitinase were studied. The accumulation of defense enzyme was greater in plants treated with a combination of T. viride and C. colocynthis compared to the control. Reduction of wilt disease in tomato plants due to the involvement of defense-related enzymes is presumed through this experiment.


Subject(s)
Citrullus colocynthis , Fusarium , Solanum lycopersicum , Antifungal Agents/pharmacology , Methanol , Spectroscopy, Fourier Transform Infrared , Plant Diseases/prevention & control , Plant Diseases/microbiology
2.
Article in English | MEDLINE | ID: mdl-36889534

ABSTRACT

Aluminium (Al) is proven to be a potent environmental neurotoxin involved in progressive neurodegeneration. Al primarily induces oxidative stress by free radical generation in the brain, followed by neuronal apoptosis. Antioxidants are promising therapeutic options for Al toxicity. Piperlongumine is traditionally long known for its medicinal properties. Therefore, the present study has been designed to explore the antioxidant role of trihydroxy piperlongumine (THPL) against Al-induced neurotoxicity in the zebrafish model. Zebrafish exposed to AlCl3 exhibited higher oxidative stress and altered locomotion. Adult fish displayed anxiety comorbid with depression phenotype. THPL increases antioxidant enzyme activity by quenching Al-induced free radicals and lipid peroxidation, thus minimizing oxidative damage in the brain. THPL rescues behavior deficits and improves anxiety-like phenotype in adult fish. Histological alterations caused by Al were also attenuated on administration with THPL. Results of the study demonstrate the neuroprotective role of THPL against Al-induced oxidative damage and anxiety, which could be exploited as a psychopharmacological drug.


Subject(s)
Aluminum , Antioxidants , Animals , Antioxidants/pharmacology , Antioxidants/metabolism , Aluminum/toxicity , Aluminum Chloride , Zebrafish/metabolism , Aluminum Compounds/toxicity , Chlorides/toxicity , Oxidative Stress
3.
Toxics ; 11(2)2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36850985

ABSTRACT

Arsenic (As) is a toxic contaminant present in organic and inorganic forms in the environment. Nobiletin (NOB) is a polymethoxy flavone that has recently gained substantial consideration due to its curative impacts. The present experiment was conducted to assess the hepatoprotective efficiency of NOB on As-generated hepatotoxicity. Twenty-four adult rats were equally distributed into four groups and designated as control, As (50 mg/kg)-treated, As + NOB (50 mg/kg and 25 mg/kg, respectively), and NOB (25 mg/kg)-treated groups. After 30 days, experimental animals were decapitated, then blood and tissue samples were collected for further analysis. The group treated with As showed a significant decrease in the activity of antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), glutathione (GSH), glutathione reductase (GSR), and total antioxidant status (TAS), and a substantial increase in the accumulation of As in liver tissues, levels of total oxidant status (TOS), hydrogen peroxide (H2O2), and lipid peroxidation (TBARS). Significant increases in alanine aminotransferase (ALT), alkaline phosphatase (ALP), and aspartate aminotransferase (AST) levels were observed in As-treated rats. Moreover, nuclear factor (NF)-κB, tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, interleukin (IL)-6, and cyclo-oxygenase (COX)-2 activity, as well as the levels of pro-apoptotic markers (Bax, Caspase-3, and Caspase-9) were increased on exposure to As. In contrast, the anti-apoptotic marker (Bcl-2) level was significantly decreased. As administration showed a significant disturbance in hepatic tissue histology. However, cotreatment of NOB with As considerably increased the antioxidant enzyme activity, with a noteworthy reduction in the deposition of As in hepatic tissues, TBARS, and H2O2 levels. NOB-administrated rats showed considerable recovery in terms of inflammation, apoptosis, and histological damage. Hence, NOB can be considered a useful curative compound due to its medicinal properties against As-prompted hepatotoxicity.

4.
Front Physiol ; 13: 900570, 2022.
Article in English | MEDLINE | ID: mdl-36439259

ABSTRACT

Spodoptera litura (Fabricius) is an agriculturally significant polyphagous insect pest that has evolved a high level of resistance to conventional insecticides. A dietary assay was used in this work to assess the resilience of field populations of S. litura to λ-cyhalothrin. Analysis of the function and expression of the cytochrome P450 gene was used to test the sensitivity of S. litura larvae to sub-lethal concentrations of the insecticidal plant chemical Precocene 1, both by itself and in combination with λ-cyhalothrin. The activity of esterase enzymes (α and ß) was found to decrease 48 h post treatment with Precocene 1. The activity of GST enzyme and cytochrome P450 increased with Precocene 1 treatment post 48 h, however. Expression studies revealed the modulation by Precocene 1 of cytochrome P450 genes, CYP4M16, CYP4M15, CYP4S8V4, CYP4G31, and CYP4L10. While CYP4M16 expression was stimulated the most by the synergistic Precocene 1 + λ-cyhalothrin treatment, expression of CYP4G31 was the most down-regulated by Precocene 1 exposure. Hence, it is evident that λ-cyhalothrin-resistant pest populations are still sensitive to Precocene 1 at a sublethal concentration that is nevertheless capable of hindering their development. Precocene 1 can therefore be considered a potent candidate for the effective management of insecticide-resilient S. litura.

5.
Molecules ; 27(21)2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36364155

ABSTRACT

In this study, the anti-cancer and anti-inflammatory activities of PS14, a short peptide derived from the cellulase binding domain of pathogenic fungus, Aphanomyces invadans, have been evaluated, in vitro and in vivo. Bioinformatics analysis of PS14 revealed the physicochemical properties and the web-based predictions, which indicate that PS14 is non-toxic, and it has the potential to elicit anti-cancer and anti-inflammatory activities. These in silico results were experimentally validated through in vitro (L6 or Hep-2 cells) and in vivo (zebrafish embryo or larvae) models. Experimental results showed that PS14 is non-toxic in L6 cells and the zebrafish embryo, and it elicits an antitumor effect Hep-2 cells and zebrafish embryos. Anticancer activity assays, in terms of MTT, trypan blue and LDH assays, showed a dose-dependent inhibitory effect on cell proliferation. Moreover, in the epithelial cancer cells and zebrafish embryos, the peptide challenge (i) caused significant changes in the cytomorphology and induced apoptosis; (ii) triggered ROS generation; and (iii) showed a significant up-regulation of anti-cancer genes including BAX, Caspase 3, Caspase 9 and down-regulation of Bcl-2, in vitro. The anti-inflammatory activity of PS14 was observed in the cell-free in vitro assays for the inhibition of proteinase and lipoxygenase, and heat-induced hemolysis and hypotonicity-induced hemolysis. Together, this study has identified that PS14 has anti-cancer and anti-inflammatory activities, while being non-toxic, in vitro and in vivo. Future experiments can focus on the clinical or pharmacodynamics aspects of PS14.


Subject(s)
Aphanomyces , Zebrafish , Animals , Humans , Zebrafish/metabolism , Hemolysis , Apoptosis , Epithelial Cells , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/metabolism , Peptides/pharmacology , Cellulose/metabolism , Embryo, Nonmammalian
6.
Toxics ; 10(10)2022 Sep 26.
Article in English | MEDLINE | ID: mdl-36287844

ABSTRACT

The present study aimed to determine the degree of changes in the histological architecture of the liver, gills, kidneys, and muscles of fish Oreochromis niloticus collected from different polluted river sites. Fish samples collected from the Faisalabad Fish Hatchery and upstream of Chakbandi drain acted as a control. Necrosis, hemorrhage, and epithelial hyperplasia were observed in the gills of fish inhabiting the river downstream of the Chakbandi drain entrance. Liver tissues were found to be affected by vacuolated cytoplasm, bile duct proliferation, melanomacrophages, and necrosis. In kidney tissues, shrinkage of the renal cortex, necrosis, and destructive renal tubules were observed. Histopathology of muscles indicates the presence of hypertrophy and swollen myofibers. In contrast, upstream specimens of fish exhibited mild tissue alterations. Histopathology of gills tissue showed vacuolization. Liver tissues indicated the presence of hypertrophy and more frequent Kupffer cells than usual. The vacuolation was also observed in kidney tissues. Muscle tissues expressed splitting of muscle fibres and degeneration in muscle bundles. However, sections of tissues collected from farmed fish have normal morphology and no anomalies. The histopathological assessment indicated various cellular, biochemical, and histological changes in response to the contamination in the vicinity of the fish.

7.
Braz. arch. biol. technol ; 64: e21190689, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1350263

ABSTRACT

Abstract The present research was planned to analyze the toxic effects of thimerosal on rat liver. Mercury and mercury compounds are universally known toxicants for animals and humans. Thimerosal is widely used in the vaccines as a preservative which contains 49.6% mercury. Twenty-four adult male albino rats were distributed into four groups (n=6). The first group was considered as a control group. While, second, third and fourth groups were intoxicated with 0.5, 10 and 50 µg/kg thimerosal (i.m.) respectively. After 30 days, rats were slaughtered to analyze the liver tissues. The results of the experiment exposed that thimerosal instigated significant (p<0.05) increase in alanine transaminase (ALT), alkaline phosphatase (ALP) and aminotransferase (AST) levels. Catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) activities and Glutathione (GSH) and protein levels were significantly (p<0.05) reduced. Furthermore, significant increases in Hydrogen peroxide (H2O2), thiobarbituric acid reactive substances (TBARS) level and DNA damage was observed. Histopathological study revealed severe damages, e.g. fatty alterations, deterioration of lobular structure and degeneration of nuclei in hepatic tissues of thimerosal treated rats. Results of present investigation revealed that thimerosal induces hepatotoxicity at different levels.

8.
R Soc Open Sci ; 7(1): 190669, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32218929

ABSTRACT

We hypothesized that the mitogenome of Gammarus lacustris (GL), native to the Qinghai-Tibet Plateau, might exhibit genetic adaptations to the extreme environmental conditions associated with high altitudes (greater than 3000 m). To test this, we also sequenced the mitogenome of Gammarus pisinnus (GP), whose native range is close to the Tibetan plateau, but at a much lower altitude (200-1500 m). The two mitogenomes exhibited conserved mitochondrial architecture, but low identity between genes (55% atp8 to 76.1% cox1). Standard (homogeneous) phylogenetic models resolved Gammaridae as paraphyletic, but 'heterogeneous' CAT-GTR model as monophyletic. In indirect support of our working hypothesis, GL, GP and Gammarus fossarum exhibit evidence of episodic diversifying selection within the studied Gammaroidea dataset. The mitogenome of GL generally evolves under a strong purifying selection, whereas GP evolves under directional (especially pronounced in atp8) and/or relaxed selection. This is surprising, as GP does not inhabit a unique ecological niche compared to other gammarids. We propose that this rapid evolution of the GP mitogenome may be a reflection of its relatively recent speciation and heightened non-adaptive (putatively metabolic rate-driven) mutational pressures. To test these hypotheses, we urge sequencing mitogenomes of remaining Gammarus species populating the same geographical range as GP.

9.
Genome Biol Evol ; 11(7): 1797-1812, 2019 07 01.
Article in English | MEDLINE | ID: mdl-31192351

ABSTRACT

The phylogeny of Isopoda, a speciose order of crustaceans, remains unresolved, with different data sets (morphological, nuclear, mitochondrial) often producing starkly incongruent phylogenetic hypotheses. We hypothesized that extreme diversity in their life histories might be causing compositional heterogeneity/heterotachy in their mitochondrial genomes, and compromising the phylogenetic reconstruction. We tested the effects of different data sets (mitochondrial, nuclear, nucleotides, amino acids, concatenated genes, individual genes, gene orders), phylogenetic algorithms (assuming data homogeneity, heterogeneity, and heterotachy), and partitioning; and found that almost all of them produced unique topologies. As we also found that mitogenomes of Asellota and two Cymothoida families (Cymothoidae and Corallanidae) possess inversed base (GC) skew patterns in comparison to other isopods, we concluded that inverted skews cause long-branch attraction phylogenetic artifacts between these taxa. These asymmetrical skews are most likely driven by multiple independent inversions of origin of replication (i.e., nonadaptive mutational pressures). Although the PhyloBayes CAT-GTR algorithm managed to attenuate some of these artifacts (and outperform partitioning), mitochondrial data have limited applicability for reconstructing the phylogeny of Isopoda. Regardless of this, our analyses allowed us to propose solutions to some unresolved phylogenetic debates, and support Asellota are the most likely candidate for the basal isopod branch. As our findings show that architectural rearrangements might produce major compositional biases even on relatively short evolutionary timescales, the implications are that proving the suitability of data via composition skew analyses should be a prerequisite for every study that aims to use mitochondrial data for phylogenetic reconstruction, even among closely related taxa.


Subject(s)
Genome, Mitochondrial/genetics , Isopoda/genetics , Mitochondria/genetics , Algorithms , Animals , Mutation/genetics , Phylogeny
10.
Biomolecules ; 9(6)2019 06 14.
Article in English | MEDLINE | ID: mdl-31207942

ABSTRACT

This research work was carried out to determine the effects of water contamination on the fatty acid (FA) profile of periphyton, zoobenthos, two Chinese carps and a common carp (Hypophthalmichthys molitrix, Ctenopharygodon idella and Cyprinus carpio), captured from highly polluted (HP), less polluted (LP), and non-polluted (NP) sites of the Indus river. We found that the concentration of heavy metals in the river water from the polluted locations exceeded the permissible limits suggested by the World Health Organization (WHO) and the US Environmental Protection Agency (EPA). Fatty acid profiles in periphyton, zoobenthos, H. molitrix, C. idella, and C. carpio in the food web of river ecosystems with different pollution levels were assessed. Lauric acid and arachidic acids were not detected in the biomass of periphyton and zoobenthos from HP and LP sites compared to NP sites. Alpha-linolenic acid (ALA), eicosadienoic acid and docosapentaenoic acid were not recorded in the biomass samples of periphyton and zoobenthos in both HP and LP sites. Caprylic acid, lauric acid, and arachidic acid were not found in H. molitrix, C. idella, and C. carpio captured from HP. In this study, 6 and 9 omega series FAs were identified in the muscle samples of H. molitrix, C. idella and C. carpio captured from HP and LP sites compared to NP sites, respectively. Less polyunsaturated fatty acids were observed in the muscle samples of H. molitrix, C. idella, and C. carpio collected from HP than from LP. The heavy metals showed significant negative correlations with the total FAs in periphyton, zoobenthos, and fish samples.


Subject(s)
Dinoflagellida/metabolism , Fatty Acids/metabolism , Fishes/metabolism , Food Chain , Fresh Water , Microalgae/metabolism , Water Pollution , Animals , Dinoflagellida/drug effects , Dinoflagellida/physiology , Fishes/physiology , Metals, Heavy/toxicity , Microalgae/drug effects , Microalgae/physiology , Stress, Physiological/drug effects
11.
Saudi J Biol Sci ; 26(4): 752-757, 2019 May.
Article in English | MEDLINE | ID: mdl-31049000

ABSTRACT

Fish kidneys are sensitive to chemical changes in the freshwater ecosystem because they are directly and constantly exposed to chemicals dissolved in the water. This study evaluated nephrotoxicity in Wallago attu and Cirrhinus mrigala harvested from the Chenab River in an area of industrial and sewage waste disposal. Induced histological alternation data were correlated to the severity of environmental degradation in order to determine whether this biological system can be used as a tool for environmental monitoring programs. Kidneys from two fish species occupying different niches were collected and stored for 24 h in 10% formalin. Control fish were collected upstream of the polluted river area. Specimens were processed using topical histological methods. The major histological alterations observed in both species were renal tubule myxospora, hyperemia, glomerulonephritis, degeneration of renal tubule cells, dilation of glomerular capillaries, presence of pycnotic nuclei in the hematopoietic tissue, epithelial hypertrophy, vacuolization, reduced lumen of renal tubules, and shrinkage of glomeruli. Renal tubular atrophy, degeneration due to extensive degranulation, necrosis of glomeruli, glomerular expansion, absence of Bowman's space, hypertrophied nucleus, necrosis and hyalinization of the interstitium, clogging of tubules, and regeneration of tubules was also observed. Wallago attu exhibited the maximum incidence of moderate to severe changes and was defined as having the highest "histopathologic alteration index". These severe alterations were found to be related to environmental degradation, indicating the presence of stressors in freshwater. Control groups showed normal tissue morphology in the kidneys.

12.
Anal Chem ; 90(20): 12284-12291, 2018 10 16.
Article in English | MEDLINE | ID: mdl-30234968

ABSTRACT

A novel enzyme-free photoelectrochemical (PEC) immunoassay was developed for the ultrasensitive detection of prostate specific antigen (PSA) based on the DNA-mediated nanoscale zirconium-porphyrin MOFs (NMOFs). By virtue of the intrinsic coordination between unsaturated zirconium sites of the NMOFs frameworks and phosphonate groups, the 5'-phosphorylared ss-DNA-tagged antibody (Ab-DNA) conjugate with a consecutive stretch of guanines as a spacer could be loaded on the NMOFs easily, obtaining a novel type of Ab-DNA-functionalized NMOFs complex. Additionally, as a photocathode PEC active nanomaterial, NMOFs exhibited a significant enhanced photocurrent response with the presence of dopamine under oxygen-containing aqueous media at -0.3 V (vs Ag/AgCl). Furthermore, with the aid of the electrochemical grafting of polyamidoamine (PAMAM) dendrimers functionalized interface, the novel type of Ab-DNA-NMOFs further served as a PEC signal nanoprobe for the ultrasensitive PSA immunoassay. Under optimal conditions, the corresponding immunosensor possessed a wide calibration range of 1 pg mL-1 to 10 ng mL-1 and a limit of detection (LOD) of 0.2 pg mL-1. This present work demonstrated the promising application of DNA-mediated NMOFs in developing highly sensitive, environmentally friendly, and cost-effective PEC biosensors.


Subject(s)
DNA/chemistry , Electrochemical Techniques , Immunoassay , Metal-Organic Frameworks/chemistry , Photochemical Processes , Porphyrins/chemistry , Prostate-Specific Antigen/analysis , Zirconium/chemistry , Humans
13.
PLoS One ; 13(9): e0203089, 2018.
Article in English | MEDLINE | ID: mdl-30180209

ABSTRACT

As a result of great diversity in life histories and a large number of described species, taxonomic and phylogenetic uncertainty permeates the entire crustacean order of Isopoda. Large molecular datasets capable of providing sufficiently high phylogenetic resolution, such as mitochondrial genomes (mitogenomes), are needed to infer their evolutionary history with confidence, but isopod mitogenomes remain remarkably poorly represented in public databases. We sequenced the complete mitogenome of Cymothoa indica, a species belonging to a family from which no mitochondrial genome was sequenced yet, Cymothoidae. The mitogenome (circular, 14484 bp, A+T = 63.8%) is highly compact, appears to be missing two tRNA genes (trnI and trnE), and exhibits a unique gene order with a large number of rearrangements. High compactness and the existence of palindromes indicate that the mechanism behind these rearrangements might be associated with linearization events in its evolutionary history, similar to those proposed for isopods from the Armadillidium genus (Oniscidea). Isopods might present an important model system to study the proposed discontinuity in the dynamics of mitochondrial genomic architecture evolution. Phylogenetic analyses (Bayesian Inference and Maximum Likelihood) conducted using nucleotide sequences of all mitochondrial genes resolved Oniscidea and Cymothoida suborders as paraphyletic. Cymothoa indica was resolved as a sister group (basal) to all remaining isopods, which challenges the accepted isopod phylogeny, where Cymothoida are the most derived, and Phreatoicidea the most basal isopod group. There is growing evidence that Cymothoida suborder might be split into two evolutionary distant clades, with parasitic species being the most basal split in the Isopoda clade, but a much larger amount of molecular resources carrying a high phylogenetic resolution will be needed to infer the remarkably complex evolutionary history of this group of animals with confidence.


Subject(s)
Gene Order , Genome, Mitochondrial , Isopoda/genetics , Animals , Evolution, Molecular , Phylogeny
14.
Environ Sci Pollut Res Int ; 25(10): 9730-9736, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29368200

ABSTRACT

Cirrhinus mrigala, Labeo rohita, and Catla catla are economically important fish for human consumption in Pakistan, but industrial and sewage pollution has drastically reduced their population in the River Chenab. Statistics are an important tool to analyze and interpret comet assay results. The specific aims of the study were to determine the DNA damage in Cirrhinus mrigala, Labeo rohita, and Catla catla due to chemical pollution and to assess the validity of statistical analyses to determine the viability of the comet assay for a possible use with these freshwater fish species as a good indicator of pollution load and habitat degradation. Comet assay results indicated a significant (P < 0.05) degree of DNA fragmentation in Cirrhinus mrigala followed by Labeo rohita and Catla catla in respect to comet head diameter, comet tail length, and % DNA damage. Regression analysis and correlation matrices conducted among the parameters of the comet assay affirmed the precision and the legitimacy of the results. The present study, therefore, strongly recommends that genotoxicological studies conduct appropriate analysis of the various components of comet assays to offer better interpretation of the assay data.


Subject(s)
Cyprinidae/genetics , DNA Damage , Environmental Monitoring , Mutagens/toxicity , Rivers/chemistry , Water Pollutants, Chemical/toxicity , Animals , Comet Assay , Cyprinidae/blood , Ecosystem , Ecotoxicology , Environmental Monitoring/methods , Environmental Monitoring/statistics & numerical data , Pakistan , Regression Analysis , Species Specificity
15.
Talanta ; 164: 601-607, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28107979

ABSTRACT

A novel electrochemical sensor has been facilely fabricated by applying composite elements consisting of nitrogen and sulfur co-doped activated graphene (N,S-AGR) and molecularly imprinted polymer (MIP). N,S-AGR was synthesized by one-pot pyrogenation of a mixture of thiourea, KOH and graphene oxide, which was introduced to improve electron transfer capability and surface area of the electrode, while the electro-polymerized MIP layer afforded simultaneous recognition and quantification of cyclophosphamide (CPA) by utilizing Fe(CN)63-/4- as probe to indicate electrical signals. Under the optimal conditions, a calibration curve of current shift versus concentration of CPA was got in the range of 8×10-12-8×10-7molL-1, and the developed sensor gave a remarkably low detection limit (LOD) of 3.4×10-12mol L-1 (S/N=3). Moreover, the as-prepared sensor illustrated other good merits like stability and selectivity, and played a role in real-time therapeutic drug monitoring after CPA administration in rabbit.


Subject(s)
Cyclophosphamide/analysis , Electrochemistry/instrumentation , Graphite/chemistry , Limit of Detection , Molecular Imprinting , Polymers/chemical synthesis , Animals , Calibration , Drug Monitoring , Electrodes , Hydrogen-Ion Concentration , Models, Molecular , Molecular Conformation , Nitrogen/chemistry , Oxidation-Reduction , Sulfur/chemistry
16.
ACS Appl Mater Interfaces ; 8(49): 33499-33505, 2016 Dec 14.
Article in English | MEDLINE | ID: mdl-27960393

ABSTRACT

A highly sensitive and multiple microRNA (miRNA) detection method by combining three-dimensional (3D) DNA tetrahedron-structured probes (TSPs) to increase the probe reactivity and accessibility with duplex-specific nuclease (DSN) for signal amplification for sensitive miRNA detection was proposed. Briefly, 3D DNA TSPs labeled with different fluorescent dyes for specific target miRNA recognition were modified on a gold nanoparticle (GNP) surface to increase the reactivity and accessibility. Upon hybridization with a specific target, the TSPs immobilized on the GNP surface hybridized with the corresponding target miRNA to form DNA-RNA heteroduplexes, and the DSN can recognize the formed DNA-RNA heteroduplexes to hydrolyze the DNA in the heteroduplexes to produce a specific fluorescent signal corresponding to a specific miRNA, while the released target miRNA strands can initiate another cycle, resulting in a significant signal amplification for sensitive miRNA detection. Different targets can produce different fluorescent signals, leading to the development of a sensitive detection for multiple miRNAs in a homogeneous solution. Under optimized conditions, the proposed assay can simultaneously detect three different miRNAs in a homogeneous solution with a logarithmic linear range spanning 5 magnitudes (10-12-10-16) and achieving a limit of detection down to attomolar concentrations. Meanwhile, the proposed miRNA assay exhibited the capability of discriminating single bases (three bases mismatched miRNAs) and showed good eligibility in the analysis of miRNAs extracted from cell lysates and miRNAs in cell incubation media, which indicates its potential use in biomedical research and clinical analysis.


Subject(s)
Nanostructures , DNA , Gold , Metal Nanoparticles , MicroRNAs , Nucleic Acid Amplification Techniques
17.
Braz. arch. biol. technol ; 56(2): 293-302, Mar.-Apr. 2013. ilus, graf, tab
Article in English | LILACS | ID: lil-675648

ABSTRACT

The aim of this work was to study the effects of sub-lethal exposure of lead acetate on the histopathology of the gills, liver, kidney and muscle and its accumulation in these organs of Clarias gariepinus. Results showed that lead accumulation in the tissues of C. gariepinus was dependent on the exposure period and lead concentration. Gills and liver were the predominant storage tissue and the order of accumulation in tissues was gill > liver > kidney > muscle. Some structural changes were observed in different organs, especially in the gills of the fishes exposed to lead acetate. Epithelial hypertrophy and epithelial lifting were apparent in the gills of exposed fishes. The degeneration of cytoplasm and secondary lamellae was also observed. Necrosis of hepatocytes was apparent. Glomerular expansion and gaps between the muscular bundles were found in the fishes exposed to lead acetate.

SELECTION OF CITATIONS
SEARCH DETAIL
...