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111.
Thymol and Carvacrol Prevent Cisplatin‐Induced Nephrotoxicity by Abrogation of Oxidative Stress,Inflammation, and Apoptosis in Rats 下载免费PDF全文
El‐Sayed EM Abd‐Allah AR Mansour AM EL‐Arabey AA 《Journal of biochemical and molecular toxicology》2015,29(4):165-172
The aim of the present study is to assess the possible protective effects of thymol and carvacrol against cisplatin (CP)‐induced nephrotoxicity. A single dose of CP {6 mg/kg, intraperitoneally (i.p.)} injected to male rats revealed significant increases in serum urea, creatinine, and tumor necrosis factor alpha levels. It also increased kidney contents of malondialdehyde and caspase‐3 activity with significant reduction in serum albumin, kidney content of reduced glutathione as well as catalase, and superoxide dismutase activity as compared to that of the control group. In contrast, administration of thymol {20 mg/kg, orally (p.o.)} and/or carvacrol (15 mg/kg, p.o.) for 14 days before CP injection and for 7 days after CP administration restored the kidney function and examined oxidative stress parameters. In conclusion, thymol was more effective nephroprotective than carvacrol. Moreover, a combination of thymol and carvacrol had a synergistic nephroprotective effect that might be attributed to antioxidant, anti‐inflammatory, and antiapoptotic activities. 相似文献
112.
Md. Parvez Anwar Md. Ariful Islam Khalid A. K. M. Mominul Islam Sabina Yeasmin Sharif Ahmed Adel Hadifa Ismail A. Ismail Akbar Hossain Ayman EL Sabagh 《Phyton》2021,90(5):1491-1506
Seed priming has proved to be an effective pre-germination seed invigoration technique for different crops to
improve seed and seedling performance under different abiotic stresses. In Bangladesh, winter rice is very often
exposed to cold waves just after sowing in the nursery bed resulting in poor seed germination and seedling emergence, yellowish and thin seedlings production, and a very low survival rate. Seed priming may mitigate the cold
stress during seed germination and seedling emergence and helps in the quality seedling production of winter rice.
To evaluate the efficacy of different seed priming techniques in increasing seedling emergence, growth, vigor and
survivability of winter rice cultivars under cold stress, a pot experiment was conducted at the Department of Agronomy, Bangladesh Agricultural University during December 2018 to January 2019. The experiment comprised
two factors, (A) Winter rice variety namely, i) BRRI dhan29 and ii) BRRI dhan36; (B) Seed priming agent namely
i) Control (no priming), ii) 20000 ppm NaCl, iii) 30000 ppm NaCl, iv) 20000 ppm KCl, v) 30000 ppm KCl, vi)
20000 ppm CaCl2, vii) 30000 ppm CaCl2, viii) 50 ppm CuSO4, ix) 75 ppm CuSO4, x) 10000 ppm ZnSO4, xi)
15000 ppm ZnSO4, xii) 2 ppm Na2MoO4, xiii) 3 ppm Na2MoO4, xiv) 100 ppm PEG (Polyethylene glycol
4000) and xv) 150 ppm PEG. Seeds were sown on two different dates viz., 1st December and 1st January so that
seedlings are exposed to cold stress at different stages. The experiment was laid out in a completely randomized
design (CRD) with three replications. Results indicated that (in most of the cases) seed priming has a positive
impact on seedling emergence rate (%), root length, shoot length, root shoot ratio, root dry weight, shoot dry
weight, seedling dry weight and survival rate (%). Among the priming agents, KCl and CaCl2 performed best;
while priming with NaCl and PEG showed no advantages over no priming for both the sowing dates. In general,
BRRI dhan36 performed better than BRRI dhan29 in terms of seedling growth because of its higher tolerance to
cold stress. But, both the varieties performed similarly in terms of emergence rate and survival rate. Thus, priming
is an effective tool to increase seed germination, better seedling growth, and higher seedling survivability of winter
rice under cold stress, and KCl (20000 ppm) or CaCl2 (20000 ppm) can be considered as a viable priming agent. 相似文献
113.
Hocine Thinhinane Blaise Sebastien Hachet Cathy Guillot Alexandre Sartelet Herve Maurice Pascal Bennasroune Amar Martiny Laurent Duca Laurent Romier-Crouzet Beatrice EL Btaouri Hassan 《Journal of physiology and biochemistry》2020,76(3):457-467
Journal of Physiology and Biochemistry - Elastin, the major protein of the extracellular matrix, is specially found in cardiovascular tissues and contributing to 30–50% of the dry weight of... 相似文献
114.
Mahmuda Binte Monsur Nasrin Akter Ivy M. Moynul Haque Mirza Hasanuzzaman Ayman EL Sabagh Md. Motiar Rohman 《Phyton》2020,89(3):497-517
The research was conducted to investigate comparative oxidative
damage including probable protective roles of antioxidant and glyoxalase systems
in rice (Oryza sativa L.) seedlings under salinity stress. Seedlings of two rice genotypes: Pokkali (tolerant) and BRRI dhan28 (sensitive) were subjected to 8 dSm−1
salinity stress for seven days in a hydroponic system. We observed significant variation between Pokkali and BRRI dhan28 in phenotypic, biochemical and molecular level under salinity stress. Carotenoid content, ion homeostasis, antioxidant
enzymes, ascorbate and glutathione redox system and proline accumulation may
help Pokkali to develop defense system during salinity stress. However, the activity antioxidant enzymes particularly superoxide dismutase (SOD), catalase (CAT)
and non-chloroplastic peroxidase (POD) were observed significantly higher in
Pokkali compared to salt-sensitive BRRI dhan28. Higher glyoxalase (Gly-I)
and glyoxalase (Gly-II) activity might have also accompanied Pokkali genotype
to reduce potential cytotoxic MG through non-toxic hydroxy acids conversion.
However, the efficient antioxidants and glyoxalase system together increased
adaptability in Pokkali during salinity stress. 相似文献
115.
Genetic footprints of late Quaternary climate change in the diversity of Patagonian‐Fueguian rodents
Species are impacted by climate change at both ecological and evolutionary time scales. Studies in northern continents have provided abundant evidence of dramatic shifts in distributions of species subsequent to the last glacial maximum (LGM), particularly at high latitudes. However, little is known about the history of southern continents, especially at high latitudes. South America is the only continent, other than Antarctica, that extends beyond 40 °S. Genetic studies of a few Patagonian species have provided seemingly conflicting results, indicating either postglacial colonization from restricted glacial refugia or persistence through glacial cycles and in situ differentiation. Using mitochondrial DNA sequences of 14 species of sigmodontine rodents, a major faunal ensemble of Patagonia and Tierra del Fuego, we show that at least nine of these species bear genetic footprints of demographic expansion from single restricted sources. However, timing of demographic expansion precedes the LGM in most of these species. Four species are fragmented phylogeographically within the region. Our results indicate that (i) demographic instability in response to historical climate change has been widespread in the Patagonian‐Fueguian region, and is generally more pronounced at high latitudes in both southern and northern continents; (ii) colonization from lower latitudes is an important component of current Patagonian‐Fueguian diversity; but (iii) in situ differentiation has also contributed to species diversity. 相似文献
116.
A cyanobacterial bloom prevents fish trophic cascades 总被引:1,自引:0,他引:1
CAROLINE RONDEL ROBERT ARFI DANIEL CORBIN FRÉDÉRIC LE BIHAN EL HADJI NDOUR XAVIER LAZZARO 《Freshwater Biology》2008,53(4):637-651
1. We experimentally compared the impacts of visually feeding zooplanktivorous fish and filter‐feeding omnivorous fish in shallow tropical Dakar Bango reservoir, Senegal. We provoked a cyanobacterial Anabaena bloom under mesotrophic to eutrophic N‐limited conditions in 18 enclosures assigned to six Nile tilapia life‐stage treatments, at typical biomasses: fishless control (C), zooplanktivorous fry (Z), omnivorous juveniles (O), herbivorous fingerlings (H) and two combinations (OZ, OH). 2. All fish grew well, but as prevalent inedible phytoplankton dampened fish effects, community‐level trophic cascades did not occur. Planktivore types acted independently and affected differentially the biomasses of total zooplankton, cyclopoids, nauplii, cladocerans, invertebrate carnivores, large herbivores, colonial cyanobacteria and Chlorophyta. They neither influenced the total biomass of phytoplankton, nor most water chemistry characteristics. Responses were apparently not fish‐biomass related. The bloom collapsed synchronously in all enclosures, coinciding with enrichment ending, with a return to clear water within 12 days. 3. Our results support the hypothesis that excess nutrients and prevalent inedible cyanobacteria inhibit the cascading effects of natural biomass levels of both visually feeding zooplanktivores and filter‐feeding omnivores. In N‐limited meso‐eutrophic shallow tropical lakes with predominantly small herbivorous zooplankton, neither the type nor the biomass of planktivorous fish present seems likely to prevent the transient outburst of cyanobacterial blooms. Such fragile ecosystems may thus not sustain a trophic state suitable for drinking water production, unless human impacts are restricted. The generality of restoration approaches based on ecological engineering should be further explored. 相似文献
117.
Open Access publishing is a valuable resource for the synthesis and distribution of essential health care information. This
article discusses the potential benefits of Open Access, specifically in terms of Low and Middle Income (LAMI) countries in
which there is currently a lack of informed health care providers - mainly a consequence of poor availability to information.
We propose that without copyright restrictions, Open Access facilitates distribution of the most relevant research and health
care information. Furthermore, we suggest that the technology and infrastructure that has been put in place for Open Access
could be used to publish download-able manuals, guides or basic handbooks created by healthcare providers in LAMI countries. 相似文献
118.
119.
A. EL TITI 《Entomologia Experimentalis et Applicata》1974,17(1):9-21
Die Eiablage von Aphidoletes aphidimyza (Rond.) konnte im Experiment durch Honigtau oder durch tote Blattläuse (Myzus persicae, Aphis fabae und Acyrthosiphon pisum), jedoch wesentlich stärker durch beide zusammen ausgelöst werden. Siphonensekret von Acyrthosiphon pisum wurde ebenfalls belegt. Dagegen gelang es nicht, die Gallmücken durch klebrige Substanzen, deren Konsistenz der des Honigtaus ähnlich ist, zur Eiablage zu bringen. Während Exuvien der Erbsenblattlaus für sich allein fast keine Wirkung zeigten, lösten sie in Kombination mit Honigtau die Eiablage ebenso stark aus wie die toten Blattläuse mit Honigtau. Dagegen waren kleine Steinchen in Blattlaus-Größe anstelle der Exuvien unwirksam. Auch Duftstoffe von Blattläusen und Honigtau führten nicht zur Eiablage. Von den Bestandteilen des Honigtaus waren bestimmte Kohlehydrate und Aminosäuren schwach, andere, vor allem Fruktose und Arginin, besser wirksam; reproduzierbar war die Wirkung nur in Kombination mit getöteten Blattläusen. 相似文献
120.
KHALIFA M. D. EL; NUR E. E. EL; LIPPINCOTT BARBARA B.; LIPPINCOTT JAMES A. 《Journal of experimental botany》1973,24(6):1117-1127
Secondary tumours were formed on the cotyledonary leaf petiole,the hypocotyl, and first true leaf of castor bean seedlingsafter inoculating the blades of the cotyledonary leaves withAgrobacterium tumefaciens. Depending on the strain of bacteriaemployed, 0 to 80 per cent of the plants developed secondarytumours. The ability of different strains to initiate secondarytumours was not obviously correlated with their relative effectivenessin initiating primary tumours. Though all produced primary tumours,five out of ten auxotrophic strains failed to yield secondarytumours, whereas only one out of 14 prototrophic strains failedto do so. Both the number of plants developing secondary tumoursand the frequency with which these tumours occurred on differentparts of the plant were positively correlated with the concentrationof the primary inoculum. Tumours also developed on the cotyledonaryleaf petiole and on the hypocotyl after vacuum infiltrationof A. tumefaciens into the blade of cotyledonary leaves. Inmost instances (9 out of 11 plants) no tumours were formed onthe blade of the infiltrated leaf. Thus, tumour formation equivalentto secondary tumours can occur in the absence of a primary tumouror an overt primary wound. Excision of inoculated leaves showedthat the stimulus for secondary tumour formation moves fromthe blade to the hypocotyl within 24 h. Attempts to demonstratethe presence of a sub-cellular tumour-initiating agent in homogenatesof inoculated leaves were unsuccessful. A. tumefaciens, however,was found in the petiole of the cotyledonary leaf and in thehypocotyl within 24 h of inoculation. The migrating agent responsiblefor secondary tumour formation in castor beans is concludedto be intact bacteria. 相似文献