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121.
122.
Summary Soybean plants were grown in pots with or without vesicular-arbuscular myocorrhizal (VAM) fungi in three soils of low plant-available
P content, different texture and different water-holding capacities. Mineral nutrients, except P, were provided in a complete
nutrient solution. The biomass of non-VAM plants was positively and fungal colonization negatively correlated with increasingly
coarse soil texture. There was no correlation of soil P with host or endophyte growth. Plant growth enhancement was positively
correlated with soil water content at −1.5 MPa. These observations suggest soil water status and the mycorrhizal condition
interact in influencing plant growth. 相似文献
123.
Chandra Prakash Prasad Satyendra Chandra Tripathi Manish Kumar Purusottam Mohapatra 《Biotechnology and bioengineering》2023,120(8):2049-2055
Cancer cell lines play a crucial role as invaluable models in cancer research, facilitating the examination of cancer progression as well as the advancement of diagnostics and treatments. While they may not perfectly replicate the original tumor, they generally exhibit similar characteristics. Low-passage cancer cell lines are generally preferred due to their closer resemblance to the original tumor, as long-term culturing can alter the genetic and molecular profiles of a cell line thereby highlighting the importance of monitoring the passage number (PN). Variations in proliferation, migration, gene expression, and drug sensitivity can be linked to PN differences. PN can also influence DNA methylation levels, metabolic profiles, and the expression of genes/or proteins in cancer cell lines. When conducting research on cancer cell lines, it is crucial for researchers to carefully select the appropriate PN to maintain consistency and reliability of results. Moreover, to ensure dependability and replicability, scientists ought to actively track the growth, migration, and gene/or protein profiles of cancer cell lines at specific PNs. This approach enables the identification of the most suitable range of PNs for experiments, guaranteeing consistent and precise results. Additionally, such efforts serve to minimize disparities and uphold the integrity of research. In this review, we have laid out recommendations for laboratories to overcome these PN discrepancies when working with cancer cell lines. 相似文献
124.
Benoit J. Arsenault Philip Barter David A. DeMicco Weihang Bao Gregory M. Preston John C. LaRosa Scott M. Grundy Prakash Deedwania Heiner Greten Nanette K. Wenger James Shepherd David D. Waters John J. P. Kastelein the Treating to New Targets Investigators 《PloS one》2014,9(12)
Several plasma non-lipid biomarkers have been shown to predict major cardiovascular events (MCVEs) in population studies. Our objective was to investigate the relationship between lipid and non-lipid biomarkers levels achieved during statin therapy and the incidence of MCVEs in patients with stable coronary heart disease (CHD). We conducted a substudy of the TNT (Treating to New Targets) study, which was a randomized trial that compared the efficacy of high (80 mg) versus low (10 mg) dose atorvastatin for the secondary prevention of CHD. Fasting plasma levels of standard lipids and of 18 non-lipid biomarkers were obtained after an 8-week run-in period on atorvastatin 10 mg in 157 patients who experienced MCVEs during the 4.9 years of study follow-up and in 1349 controls. MCVE was defined as CHD death, nonfatal, non-procedure-related myocardial infarction, resuscitated cardiac arrest, and fatal or nonfatal stroke. After adjusting for age, sex and treatment arm, plasma levels of high-density lipoprotein (HDL) cholesterol, triglycerides, high-sensitivity C-reactive protein (hsCRP), insulin, neopterin, N-terminal pro-brain natriuretic peptide (BNP), lipoprotein(a) [Lp(a)], and the soluble receptor for advanced glycation end products (sRAGE) were predictive of recurrent MCVEs (P≤0.02 for each doubling of plasma concentration). However, no significant association was observed between the risk of recurrent MCVEs and plasma levels of low-density lipoprotein cholesterol, adiponectin, cystatin C, lipoprotein-associated phospholipase A2, monocyte chemotactic protein-1, matrix metalloproteinase-9, myeloperoxidase, osteopontin, soluble CD40 ligand, soluble intercellular adhesion molecule-1, or soluble vascular cell adhesion molecule-1. After further adjustment for diabetes, hypertension, smoking, and BMI, the relationship between hsCRP, insulin and MCVE were no longer significant, while the relationship between Lp(a), neopterin, NT-proBNP and sRAGE and MCVE remained statistically significant. In conclusion, in patients with CHD treated with atorvastatin, plasma levels of Lp(a), neopterin, NT-proBNP, and sRAGE are associated with the risk of recurrent MCVEs.
Trial Registration
ClinicalTrials.gov . NCT00327691相似文献125.
126.
127.
Tiwari D Kamble J Chilgunde S Patil P Maru G Kawle D Bhartiya U Joseph L Vanage G 《Mutation research》2012,743(1-2):83-90
Bisphenol A (BPA) is a well-known endocrine disruptor (ED) which represents a major toxicological and public health concern due to its widespread exposure to humans. BPA has been reported to induce DNA adduct and aneuploidy in rodents. Recent studies in humans depicted its association with recurrent miscarriages and male infertility due to sperm DNA damage indicating that BPA might have genotoxic activity. Hence, the present study was designed to determine genotoxic and mutagenic effects of BPA using in-vivo and in-vitro assays. The adult male and female rats were orally administered with various doses of BPA (2.4 μg, 10 μg, 5mg and 50mg/kgbw) once a day for six consecutive days. Animals were sacrificed, bone marrow and blood samples were collected and subjected to series of genotoxicity assay such as micronucleus, chromosome aberration and single cell gel electrophoresis (SCGE) assay respectively. Mutagenicity was determined using tester strains of Salmonella typhimurium (TA 98, TA 100 and TA 102) in the presence and absence of metabolically active microsomal fractions (S9). Further, we estimated the levels of 8-hydroxydeoxyguanosine, lipid per-oxidation and glutathione activity to decipher the potential genotoxic mechanism of BPA. We observed that BPA exposure caused a significant increase in the frequency of micronucleus (MN) in polychromatic erythrocytes (PCEs), structural chromosome aberrations in bone marrow cells and DNA damage in blood lymphocytes. These effects were observed at various doses tested except 2.4 μg compared to vehicle control. We did not observe the mutagenic response in any of the tester strains tested at different concentrations of BPA. We found an increase in the level of 8-hydroxydeoxyguanosine in the plasma and increase in lipid per-oxidation and decrease in glutathione activity in liver of rats respectively which were exposed to BPA. In conclusion, the data obtained clearly documents that BPA is not mutagenic but exhibit genotoxic activity and oxidative stress could be one of the mechanisms leading to genetic toxicity. 相似文献
128.
In living cells, polypeptide chains emerging from ribosomes and preexisting polypeptide chains face constant threat of misfolding and aggregation. To prevent protein aggregation and to fulfill their biological activity, generally, protein must fold into its proper three-dimensional structure throughout their lifetimes. Eukaryotic cell possesses a quality control (QC) system to contend the problem of protein misfolding and aggregation. Cells achieve this functional QC system with the help of molecular chaperones and ubiquitin-proteasome system (UPS). The well-conserved UPS regulates the stability of various proteins and maintains all essential cellular function through intracellular protein degradation. E3 ubiquitin ligase enzyme determines specificity for degradation of certain substrates via UPS. New emerging evidences have provided considerable information that various E3 ubiquitin ligases play a major role in cellular QC mechanism and principally designated as QC E3 ubiquitin ligases. Nevertheless, very little is known about how E3 ubiquitin ligase maintains QC mechanism against abnormal proteins under various stress conditions. Here in this review, we highlight and discuss the functions of various E3 ubiquitin ligases implicated in protein QC mechanism. Improving our knowledge about such processes may provide opportunities to modulate protein QC mechanism in age-of-onset diseases that are caused by protein aggregation. 相似文献
129.
Lakshmi D Gopinath K Jayanthy G Anjum S Prakash D Sudhandiran G 《Neurochemical research》2012,37(9):1859-1867
Acrylamide (ACR) is a known industrial toxic chemical that produce neurotoxicity characterized by progressive neuronal degeneration. This study was designed to investigate the protective effect of fish oil on ACR-induced neuronal damage in Wistar rats. ACR enhances the production of reactive oxygen species and potentially affects brain. ACR administered rats showed increased levels of lipid peroxidative product, protein carbonyl content, hydroxyl radical and hydroperoxide which were significantly modulated by the supplementation of fish oil. The activities of enzymic antioxidants and levels of reduced glutathione were markedly lowered in ACR-induced rats; fish oil treatment augmented these antioxidant levels in cortex. Free radicals generated during ACR administration reduced the activities of membrane adenosine triphosphatases and acetylcholine esterase. Fish oil enhanced the activities of these enzymes near normal level. Histological observation represented the protective role of fish oil in ACR-induced neuronal damage. Fish oil reduced the ACR-induced apoptosis through the modulation in expressions of B-cell lymphoma 2 (Bcl2)-associated X protein and Bcl2-associated death promoter. Further, fish oil increases the expression of heat shock protein 27 (Hsp27) in ACR-induced rats. This study provides evidence for the neuroprotective effect of fish oil on ACR-induced neurotoxicity by reducing oxidative stress and apoptosis with modulation in the expression of Hsp27. 相似文献
130.
Grover A Katiyar SP Jeyakanthan J Dubey VK Sundar D 《Journal of biomolecular structure & dynamics》2012,30(4):474-487
Leishmaniasis (1) is an endemic disease mainly caused by the protozoan Leishmania donovani (Ld). Polyamines have been identified as essential organic compounds for the growth and survival of Ld. These are synthesized in Ld by polyamine synthesis pathway comprising of many enzymes such as ornithine decarboxylase (ODC), spermidine synthase (SS), and S-adenosylmethionine decarboxylase. Inhibition of these enzymes in Ld offers a viable prospect to check its growth and development. In the present work, we used computational approaches to search natural inhibitors against ODC and SS enzymes. We predicted three-dimensional structures of ODC and SS using comparative modeling and molecular dynamics (MD) simulations. Thousands of natural compounds were virtually screened against target proteins using high throughput approach. MD simulations were then performed to examine molecular interactions between the screened compounds and functional residues of the active sites of the enzymes. Herein, we report two natural compounds of dual inhibitory nature active against the two crucial enzymes of polyamine pathway of Ld. These dual inhibitors have the potential to evolve as lead molecules in the development of antileishmanial drugs. (1)These authors contributed equally. 相似文献