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921.
Bilal Hussain Maleeha Fatima Khalid Abdullah Al-Ghanim Shahid Mahboob 《Saudi Journal of Biological Sciences》2019,26(4):752-757
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. 相似文献
922.
Pmela Juliana Furlan‐Murari Claudete de Fatima Ruas Eduardo Augusto Ruas Lucas Milanez Benício Angela Maria Urrea‐Rojas Angela Rocio Poveda‐Parra Emerson Murari Ed Christian Suzuki de Lima Felipe Pinheiro de Souza Nelson Mauricio Lopera‐Barrero 《Ecology and evolution》2019,9(5):2706-2714
The golden mussel, Limnoperna fortunei a highly invasive species in Brazil, has generated productive, economical, and biological impacts. To evaluate genetic structure and variability of L. fortunei populations present in fish farms in the reservoirs of Canoas I (CANFF), Rosana (ROSFF), and Capivara (CAPFF) (Paranapanema River, Paraná, Brazil), eight microsatellite loci were amplified. Five of those eight loci resulted in 38 alleles. The observed heterozygosity (Ho) was lower than the expected heterozygosity (He) in all populations, with a deviation from the Hardy–Weinberg equilibrium (HWE). The average value for the inbreeding coefficient (Fis) was positive and significative for all populations. There was higher genetic variability within populations than among them. The fixation index (Fst) showed a small genetic variability among these populations. The occurrence of gene flow was identified in all populations, along with the lack of a recent bottleneck effect. The clustering analysis yielded K = 2, with genetic similarity between the three populations. The results demonstrate low genetic structure and suggest a founding population with greater genetic variability (ROSFF). Our data point to the possible dispersal of L. fortunei aided by anthropic factors in the upstream direction. It was concluded that the three populations presented a unique genetic pool for Paranapanema River, with occurrence of gene flow. 相似文献
923.
Gonzalez Antonio; Pfeiffer Fatima; Schmid Andreas; Schulz Irene 《American journal of physiology. Cell physiology》1998,275(3):C810
We have used fluo3-loaded mouse pancreatic acinar cells to investigate the relationshipbetween Ca2+ mobilization andintracellular pH (pHi). TheCa2+-mobilizing agonist ACh (500 nM) induced a Ca2+ release in theluminal cell pole followed by spreading of the Ca2+ signal toward the basolateralside with a mean speed of 16.1 ± 0.3 µm/s. In the presence of anacidic pHi, achieved by blockade of theNa+/H+exchanger or by incubation of the cells in aNa+-free buffer, a slowerspreading of ACh-evoked Ca2+ waveswas observed (7.2 ± 0.6 µm/s and 7.5 ± 0.3 µm/s,respectively). The effects of cytosolic acidification on thepropagation rate of ACh-evokedCa2+ waves were largely reversibleand were not dependent on the presence of extracellularCa2+. A reduction in the spreadingspeed of Ca2+ waves could also beobserved by inhibition of the vacuolarH+-ATPase with bafilomycinA1 (11.1 ± 0.6 µm/s), whichdid not lead to cytosolic acidification. In contrast, inhibition of theendoplasmic reticulum Ca2+-ATPaseby 2,5-di-tert-butylhydroquinone ledto faster spreading of the ACh-evokedCa2+ signals (25.6 ± 1.8 µm/s), which was also reduced by cytosolic acidification or treatmentof the cells with bafilomycin A1.Cytosolic alkalinization had no effect on the spreading speed of theCa2+ signals. The data suggestthat the propagation rate of ACh-induced Ca2+ waves is decreased byinhibition of Ca2+ release fromintracellular stores due to cytosolic acidification or toCa2+ pool alkalinizationand/or to a decrease in the proton gradient directed from theinositol 1,4,5-trisphosphate-sensitiveCa2+ pool to the cytosol. 相似文献
924.
Ronan Jambou Fatima El-Assaad Valery Combes Georges Emile Grau 《The international journal of biochemistry & cell biology》2009,41(7):1467-1470
A dysregulated host immune response, as opposed to the intrinsic virulence of a microbial pathogen induces a large part of the pathology seen in infectious diseases. However, current therapies are designed to target the pathogen rather than the underlying pathogenic mechanisms responsible for the manifestation of the pathology. Recent studies have highlighted the role of endothelial cell alteration in the pathology induced in sepsis and cerebral malaria. The endothelial onslaught described, is similar to that seen during ischemia reperfusion in stroke. Protecting endothelial cell membranes during sepsis and cerebral malaria, using citicoline in the same way as in stroke, has thus emerged as a new strategy that needs to be evaluated urgently. Citicoline is a natural compound that is registered for use in ischemic stroke, head trauma and neurological disorders. It enters the phosphatidylcholine synthesis pathway as a rate-limiting step and is involved in the modulation of a large number of metabolic pathways and neurotransmitter levels, and also in the biosynthesis of phospholipids in neuronal membranes. This short review highlights the potential role of citicoline as part of adjunct therapy in the treatment of infectious diseases. 相似文献
925.
Ansari FL Wadood A Ullah A Iftikhar F Ul-Haq Z 《Journal of enzyme inhibition and medicinal chemistry》2009,24(1):151-156
In continuation of our previous study on the urease inhibition by a number of chalcones, 2,3-dihydro-1,5-benzothiazepines and 2,3,4,5-tetrahydro-1,5-benzothiazepines, FlexX docking has been exploited to get a deeper insight into the mechanism of their inhibitory action. A comparison of the IC(50) values of the active compounds reveals that, of the three classes of compounds studied, 2,3-dihydro-1,5-benzothiazepines were the most potent urease inhibitors. An in silico examination of these compounds showed that the activity is related to the interaction of ligand with the nickel metallocentre, its interaction with two amino acid residues, Asp224 and Cys322, in addition to the orientation of rings A and B in the catalytic core of the enzyme. The most active compound 2,3-dihydro-1,5-benzothiazepine (4) anchor tightly through a network of interactions with Ni701 and Ni702. This includes a number of hydrogen bonds and hydrophobic contacts with the amino acid residues in its vicinity. For their reduced analogs, the difference in the activity of different diastereomers has been observed to be configuration-dependent. This may be ascribed mainly to the difference in the orientation of ring B of the two stereoisomers and the extent of their interaction with Asp224 and Cys322 present in the catalytic core of the enzyme. 相似文献
926.
Imed Messaoudi Jihen El Heni Fatima Hammouda Khaled Saïd Abdelhamid Kerkeni 《Biological trace element research》2009,130(2):152-161
The present study was conducted to investigate whether the combined treatment with Se and Zn offers more beneficial effects
than that provided by either of them alone in reversing Cd-induced oxidative stress in the kidney of rat. For this purpose,
30 adult male Wistar albino rats, equally divided into control and four treated groups, received either 200 ppm Cd (as CdCl2), 200 ppm Cd + 500 ppm Zn (as ZnCl2), 200 ppm Cd + 0.1 ppm Se (as Na2SeO3), or 200 ppm Cd + 500 ppm Zn + 0.1 ppm Se in their drinking water for 35 days. The results showed that Cd treatment decreased
significantly the catalase (CAT) and glutathione peroxidase (GSH-Px) activities, whereas the superoxide dismutase (SOD) activity
and the renal levels of lipid peroxidation (as malondialdehyde, MDA) were increased compared to control rats. The treatment
of Cd-exposed rats with Se alone had no significant effect on the Cd-induced increase in the MDA concentrations but increased
significantly the CAT activities and reversed Cd-induced increase in SOD activity. It also partially prevented Cd-induced
decrease in GSH-Px activity. The treatment of Cd-exposed animals with Zn alone increased significantly the CAT activity and
partially protected against Cd-induced increase in the MDA concentrations, whereas it had no significant effect on the Cd-induced
increase in SOD activity and decrease in GSH-Px activity. The combined treatment of Cd-exposed animals with Se and Zn was
more effective than that with either of them alone in reversing Cd-induced decrease in CAT and GSH-Px activities and Cd-induced
increase in MDA concentrations. Results demonstrated beneficial effects of combined Se and Zn treatment in Cd-induced oxidative
stress in kidney and suggest that Se and Zn can have a synergistic role against Cd toxicity.
I. Messaoudi and J. El Heni have equally contributed to this work. 相似文献
927.
928.
The present study describes the potential of in vitro grown adventitious roots of Hypericum perforatum L. commonly known as St. John’s wort at low nutrient and auxin levels in the liquid medium for micropropagation. Roots were
regenerated from shoot-derived callus on MS medium containing 4.0 mg l−1 Indole-3 acetic acid (IAA). IAA and Indole-3 butyric acid (IBA) were equally effective for the induction of roots from shoot
cultures. Half strength MS medium containing 1.0 mg l−1 IAA was most found suitable for culturing roots in liquid medium. A total biomass of 4.13 ± 0.67 g comprising 226 ± 34.4
shoots and shoot buds along with roots was obtained per culture starting with 200 mg roots inoculum. Pretreatment with kinetin
(2.0 mg l−1) enhanced the shoot multiplication. Shoots proliferated profusely from excised roots in static liquid medium supported with
glass bead matrix. Growtek™ vessel was found suitable and cost effective system for high throughput plantlet production. In vitro grown roots regardless
of their source of origin were an excellent and easy to handle source of explant for aseptic production of plantlets without
loosing the morphogenetic potential over the generations. The plants exhibited 84–99% similarity among themselves through
RAPD. The in vitro shoots produced can either be multiplied or rooted perpetually, and alternatively they can also be explored
for the in vitro production of hypericin and hyperforin. 相似文献
929.
930.
Michael Wallner Martin Himly Angela Neubauer Anja Erler Michael Hauser Claudia Asam Sonja Mutschlechner Christof Ebner Peter Briza Fatima Ferreira 《PloS one》2009,4(12)