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991.
992.
Haiman Mu Haiwen Liu Jiayi Zhang Jianhua Huang Chen Zhu Yue Lu Yueping Shi Yi Wang 《Journal of cellular and molecular medicine》2019,23(3):2174-2183
In addition to the known antitumour effects of ursolic acid (UA), increasing evidence indicates that this molecule plays a role in cardiac protection. In this study, the effects of ursolic acid on the heart in mice treated with doxorubicin (DOX) were assessed. The results showed that ursolic acid improved left ventrical fractional shortening (LVFS) and left ventrical ejection fraction (LVEF) of the heart, increased nitrogen oxide (NO) levels, inhibited reactive oxygen species (ROS) production and decreased cardiac apoptosis in mice treated with doxorubicin. Mechanistically, ursolic acid increased AKT and endothelial nitric‐oxide synthase (eNOS) phosphorylation levels, and enhanced eNOS expression, while inhibiting doxorubicin induced eNOS uncoupling through NADPH oxidase 4 (NOX4) down‐regulation. These effects of ursolic acid resulted in heart protection from doxorubicin‐induced injury. Therefore, ursolic acid may be considered a potential therapeutic agent for doxorubicin‐associated cardiac toxicity in clinical practice. 相似文献
993.
Paraoxonase is an HDL-associated enzyme that plays a preventive role against oxidative stress, which is thought to contribute
to cancer development. PON1 activity varies widely among individuals, which is in part related to two common nonsynonymous
polymorphisms in the PON1 gene (Q192R and L55M). The polymorphisms in PON1 have been implicated in cancer risk. However, results
from the studies to date have been conflicting. To clarify the association, a meta-analysis was performed for 7,073 cases
and 9,520 controls from 25 published case–control studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used
to assess the strength of the association. Significant associations between PON1-L55M but not Q192R polymorphism and total
cancer were observed from all the comparisons. In stratified analyses, PON1-55M allele was a risk factor for breast cancer.
Similarly, increased risk was observed for prostate cancer (OR = 1.18, 95% CI: 1.01–1.36, P
heterogeneity = 0.260) and Caucasian population (OR = 1.18, 95% CI: 1.02–1.38, P
heterogeneity = 0.1) of the LM genotype, compared with the LL genotype. For PON1-Q192R polymorphism, PON1-192R allele was a decreased risk
factor for cancer in the Asian group (RR vs QQ: OR = 0.61, 95% CI: 0.38–0.98, P
heterogeneity = 0.268; QR vs QQ: OR = 0.71, 95% CI: 0.52–0.96, P
heterogeneity = 0.130; RR + QR vs QQ: OR = 0.71, 95% CI: 0.53–0.95, P
heterogeneity = 0.135). Although some modest bias could not be eliminated, this meta-analysis suggests that the PON1-55M allele is a risk factor for the development of cancer, in particular for breast cancer. Future studies with larger sample
sizes are warranted to further evaluate these associations. 相似文献
994.
Peng Wang Yongzhong Xing Zhikang Li Sibin Yu 《Molecular breeding : new strategies in plant improvement》2012,29(4):903-913
To facilitate marker-assisted transfer of desirable genes for improvement of yield traits, we used a set of backcross recombinant
inbred lines (BRIL) derived from two elite parental lines, ‘Zhenshan97’ and ‘93-11’, to resolve a quantitative trait loci
(QTL) cluster for heading date and yield-related traits in rice. Four main-effect QTL (qHD6.1, qHD6.2, qHD7, and qHD8) and four epistatic QTL affecting heading date in the BRIL were detected in two experimental trials. The major QTL (qHD8) was confirmed in three heterogeneous inbred families (HIF) that segregated for this target region, and narrowed down to
a 20-kb segment in a large HIF-derived population. qHD8 was found to interact with qHD7 and had a pleiotropic effect responsible for heading date and yield components. To test usability of the identified QTL in
rice improvement, we further developed near-isogenic lines (NIL) containing one or more target genes by marker-assisted transfer
of ‘93-11’ alleles at qHD8, qHD7, and qHD6.1, and the GS3 gene for grain size into ‘Zhenshan97’. The pyramid line NIL(qHD8 + GS3) had higher yield potential, longer grains, and a more suitable heading date than ‘Zhenshan97’. Comparison of the NIL showed
existence of epistasis between alleles at different loci and background effect on qHD8, which are very important for pyramiding of desirable alleles at the target QTL. These results will be particularly useful
not only to understand the genetic basis of yield-related traits but also to improve the efficiency of marker-assisted selection
for favorable loci in rice breeding programs. 相似文献
995.
The objective was to investigate, using a mouse model, the effects of caffeine on the number of ovulated oocytes, the rate of oocyte maturation, the susceptibility of oocytes to activating stimuli, spindle morphology, and distribution of cortical granules (CGs). Mice were given caffeine (150 mg/kg body weight ip) at various times relative to hCG (-2, 0, and +2h); in an in vitro study, 1, 5 or 10 mM caffeine was added to the maturation culture. Caffeine had no effect on the quality of oocytes in vivo maturation, but caffeine was detrimental to the quality of oocytes matured in vitro. Further studies are needed to determine caffeine concentration in follicles relative to that in culture medium. 相似文献
996.
The preparation of novel steroidal heterocycles containing the 7-aryl-substituted 1,2,4-triazolo[1,5-a]pyrimidine moiety fused to the 16,17-positions of the steroid nucleus is described. The Aldol reaction of 4-aza-androst-3,17-dione (1a) and dehydroepiandrosterone (DHEA, 1b) with aromatic aldehydes was catalyzed by KF/Al(2)O(3) to give the corresponding 3-oxo-4-aza-5α- and 3β-hydroxy-5-en-16-arylidene-17-ketosteroids (2a-r). Subsequently, the intermediates 2a-r reacted with dinucleophilic 3-amino-1,2,4-triazole in presence of t-BuOK to afford the title compounds (3a-r). All the synthesized heterosteroids are new and are currently being evaluated for their biological activities. 相似文献
997.
The ethoxy chains of short ethoxy chain nonylphenol (NPEOav2.0, containing average 2.0 ethoxy units) were dehydrogenated by cell-free extracts from Ensifer sp. strain AS08 grown on a basal medium supplemented with NPEOav2.0. The reaction was coupled with the reduction in 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide and phenazine
methosulfate. The enzyme (NPEOav2.0 dehydrogenase; NPEO-DH) was purified to homogeneity with a yield of 20% and a 56-fold increase in specific activity. The
molecular mass of the native enzyme was 120 kDa, consisting of two identical monomer units (60 kDa). The gene encoding NPEO-DH
was cloned, which consisted of 1,659 bp, corresponding to a protein of 553 amino acid residues. The deduced amino acid sequence
agreed with the N-terminal amino acid sequence of the purified NPEO-DH. The presence of a flavin adenine dinucleotide (FAD)-binding
motif and glucose–methanol–choline (GMC) oxidoreductase signature motifs strongly suggested that the enzyme belongs to the
GMC oxidoreductase family. The protein exhibited homology (40–45% identity) with several polyethylene glycol dehydrogenases
(PEG-DHs) of this family, but the identity was lower than those (approximately 58%) among known PEG-DHs. The substrate-binding
domain was more hydrophobic compared with those of glucose oxidase and PEG-DHs. The recombinant protein had the same molecular
mass as the purified NPEO-DH and dehydrogenated PEG400-2000, NPEOav2.0 and its components, and NPEOav10, but only slight or no activity was found using diethylene glycol, triethylene glycol, and
PEG200.
English edition: The paper was edited by a native speaker through American Journal Experts (). 相似文献
998.
Hepatitis C virus (HCV) is able to induce autophagy via endoplasmic reticulum (ER) stress, but the exact molecular signaling pathway is not well understood. We found that the activity of the mechanistic target of rapamycin complex 1 (MTORC1) was inhibited in Huh7 cells either harboring HCV-N (genotype 1b) full-genomic replicon or infected with JFH1 (genotype 2a) virus, which led to the activation of UNC-51-like kinase 1 (ULK1) and thus to autophagy. We then analyzed activity upstream of MTORC1, and found that both protein kinase, AMP-activated, α (PRKAA, including PRKAA1 and PRKAA2, also known as AMP-activated protein kinase, AMPKα) and AKT (refers to pan AKT, including three isoforms of AKT1-3, also known as protein kinase B, PKB) were inhibited by HCV infection. The inhibition of the AKT-TSC-MTORC1 pathway contributed to upregulating autophagy, but inhibition of PRKAA downregulated autophagy. The net effect on autophagy was from AKT, which overrode the inhibition effect from PRKAA. It was further found that HCV-induced ER stress was responsible for the inhibition of the AKT pathway. Metformin, a PRKAA agonist, inhibited HCV replication not only by activating PRKAA as previously reported, but also by activating AKT independently of the autophagy pathway. Taken together, our data suggested HCV inhibited the AKT-TSC-MTORC1 pathway via ER stress, resulting in autophagy, which may contribute to the establishment of the HCV-induced autophagy. 相似文献
999.
This paper deals with the botanical study of a family funerary enclosure located in the Porta Nocera necropolis in Pompeii
(southwestern Italy). This study is part of a Franco-Italian programme investigating Roman funerary rituals. The choice of
the context was due to the exceptional preservation of the archaeological features, which offered the opportunity to observe
the remains of the proceedings which took place in a funerary enclosure in great detail. An adequate methodology had to be
developed and a 3D recording of every single artefact or ecofact has been made. Both ground surfaces and graves provided botanical
results. Those from the ground surfaces consisted mainly of fruit offering residues (especially fig and grape), while a much
wider range of species was observed in the tombs, including cereals, pulses, other kinds of fruits, weeds and bread/pastry.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
1000.
Bengt Steen 《The International Journal of Life Cycle Assessment》2007,12(2):103-108
Goal, Scope and Background The life cycles of many products including textiles contain chemicals for which process flow data are not known or are too
time consuming to collect. Although each chemical may not contribute significantly to the LCA results of the product, which
might justify excluding them, but together their contribution could be significant. Similarly, rough estimates of the process
flows for the production of a single chemical may be very uncertain and considered meaningless, while the estimates of the
cumulative data of process flows for several chemicals may be less uncertain and be a meaningful contribution to the quality
of the LCA results. There are methods for estimation of process flows for different types of products, with varying demands
regarding input data and time and with varying accuracy of the results. This work contributes to the available methods, focusing
on simple estimations for production of chemical substances. The goal was to create a fast method for estimation of emissions,
resource and energy flows (process flows) for the production of chemicals, based on easily available data on the properties
of the chemicals. The process flows investigated were limited to those normally associated with process industries and contributing
most to depletion of resources, to global warming, acidification, eutrophication and photochemical ozone production, i.e.
use of energy, crude oil, coal, natural gas, uranium in ore and emissions of CO2, SOx, NOx, NMVOC, methane, BOD, COD and total
N. Toxic substances were excluded, since toxic emissions are substance specific and cannot be included in a generalization.
Method Available data for the process flows for the production of chemicals of mainly fossil origin were correlated to properties
of chemicals such as amount of carbon in the molecule, heat of formation and average number of chemical reaction steps in
the production. The production procedures were found in readily available literature. Up to about six reaction steps were
evaluated in the correlation study. The variations in the process flows among the chemicals studied were calculated.
Results and Discussion There were weak correlations between average number of chemical reaction steps in the production and energy use, COD measured
in water emissions, and SOx and NOx emissions to air. For the remaining properties of chemicals and process flows, there were
only weak correlations for share of double bonding in the molecule if only molecules containing double bondings were included.
Conclusions The precision in estimation of the process flows increases non-significantly when adding information on the number of reaction
steps or share of double bonding for chemicals containing double bonding is added.
Recommendations and Outlook It seems reasonable to start with a simple grouping method to estimate the process flows for the production of a chemical
of fossil origin. Further investigations might investigate whether there is a correlation between process flows and the costs
of chemicals, and further study the correlations between process flows and share of double bonding for chemicals containing
double bondings. 相似文献