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91.
Exposure to lead (Pb) is associated with serious health problems including hepatorenal toxicity. Apigenin is a natural-sourced flavonoid with promising antioxidant and anti-inflammatory effects. In this research, we investigated the potential protective role of apigenin against lead acetate (PbAc)-induced hepatorenal damage. Thus, this experiment studied the exposure of male Wistar Albino rats to apigenin and/or PbAc and their effects in comparison to the control rats. Apigenin administration decreased the levels of Pb and prevented the histopathological deformations in liver and kidney tissues following PbAc exposure. This was confirmed by the normalized levels of liver and kidney function markers. Additionally, apigenin inhibited significantly oxidative reactions through upregulating Nrf2 and HO-1, and activating their downstreamed antioxidants accompanied by a marked depletion of pro-oxidants. Moreover, apigenin decreased the elevated pro-inflammatory cytokines and inhibited cell loss in liver and kidney tissues in response to PbAc intoxication in both tissues. The obtained results demonstrated that apigenin could be used to attenuate the molecular, biochemical, and histological alterations associated with Pb exposure due to its potent antioxidant, anti-inflammatory, and antiapoptotic effects.  相似文献   
92.
The regulation of signal transmission and biological processes, such as cell proliferation, apoptosis, metabolism, migration, and angiogenesis are greatly influenced by the PI3K/AKT signaling pathway. Highly conserved endogenous non-protein-coding RNAs known as microRNAs (miRNAs) have the ability to regulate gene expression by inhibiting mRNA translation or mRNA degradation. MiRNAs serve key role in PI3K/AKT pathway as upstream or downstream target, and aberrant activation of this pathway contributes to the development of cancers. A growing body of research shows that miRNAs can control the PI3K/AKT pathway to control the biological processes within cells. The expression of genes linked to cancers can be controlled by the miRNA/PI3K/AKT axis, which in turn controls the development of cancer. There is also a strong correlation between the expression of miRNAs linked to the PI3K/AKT pathway and numerous clinical traits. Moreover, PI3K/AKT pathway-associated miRNAs are potential biomarkers for cancer diagnosis, therapy, and prognostic evaluation. The role and clinical applications of the PI3K/AKT pathway and miRNA/PI3K/AKT axis in the emergence of cancers are reviewed in this article.  相似文献   
93.
A new series of benzoxazole derivatives were designed and synthesised to have the main essential pharmacophoric features of VEGFR-2 inhibitors. Cytotoxic activities were evaluated for all derivatives against two human cancer cell lines, MCF-7 and HepG2. Also, the effect of the most cytotoxic derivatives on VEGFR-2 protein concentration was assessed by ELISA. Compounds 14o, 14l, and 14b showed the highest activities with VEGFR-2 protein concentrations of 586.3, 636.2, and 705.7 pg/ml, respectively. Additionally, the anti-angiogenic property of compound 14b against human umbilical vascular endothelial cell (HUVEC) was performed using a wound healing migration assay. Compound 14b reduced proliferation and migratory potential of HUVEC cells. Furthermore, compound 14b was subjected to further biological investigations including cell cycle and apoptosis analyses. Compound 14b arrested the HepG2 cell growth at the Pre-G1 phase and induced apoptosis by 16.52%, compared to 0.67% in the control (HepG2) cells. The effect of apoptosis was buttressed by a 4.8-fold increase in caspase-3 level compared to the control cells. Besides, different in silico docking studies were also performed to get better insights into the possible binding mode of the target compounds with VEGFR-2 active sites.  相似文献   
94.
Population trends of cereal aphids and their associated parasitoids inhabiting wheat plantations were monitored by yellow sticky traps. The identified aphids exhibited one seasonal peak for each and were found to be active during the first half of March. Data revealed that, Rhopalosiphum padi L peak occurred one week later than both of Schizaphis graminum (Rondani) and Rhopalosiphum maidis (Fitch). The numbers of aphid complex was recorded more at 90 than at 30 and 60 cm height. Hymenopterous parasitoids activity is synchronised with aphid species, whereas they appeared in small numbers at early and late wheat season and showed their peak on March, with a positive correlation coefficient with aphid populations. The tested compounds (Karate, Biscaya, Match 5% EC, Tracer 24% SC and Neem Azal T/S) showed 100% reduction in aphid numbers after 24 h post application. However, the general reduction percentages indicated 99.31 > 98.32 > 97.97 > 97.06 > 95.66%, by using the abovementioned compounds, respectively.  相似文献   
95.
Plant identification, classification, and genotyping within a germplasm collection are essential elements for establishing a breeding program that enhances the probability of plants with desirable characteristics in the market place. In this study, random amplified polymorphic DNA (RAPD) was used as a molecular tool to assess the diversity and relationship among 20 summer squash (Curcubita pepo L.) landraces traditionally used to treat hypertension and prostate hyperplasia. A total of 10 RAPD primers produced 65 reproducible bands of which 46 (70.77 %) were polymorphic, indicating a large number of genotypes within the summer squash lines. Cluster analysis divided the summer squash germplasm into two groups, one including one landrace and a second containing 19 landraces that could be divided into five sub-groups. Results of this study indicate the potential of RAPD markers for the identification and assessment of genetic variations among squash landraces and provide a number of choices for developing a successful breeding program to improve summer squash.  相似文献   
96.
The establishment of baseline data on parasites from wild primates is essential to understand how changes in habitat or climatic disturbances will impact parasite–host relationships. In nature, multiparasitic infections of primates usually fluctuate temporally and seasonally, implying that the acquisition of reliable data must occur over time. Individual parasite infection data from two wild populations of New World primates, the saddleback (Leontocebus weddelli) and emperor (Saguinus imperator) tamarin, were collected over 3 years to establish baseline levels of helminth prevalence and parasite species richness (PSR). Secondarily, we explored variation in parasite prevalence across age and sex classes, test nonrandom associations of parasite co‐occurrence, and assess the relationship between group size and PSR. From 288 fecal samples across 105 individuals (71 saddleback and 34 emperor tamarins), 10 parasite taxa were identified by light microscopy following centrifugation and ethyl‐acetate sedimentation. Of these taxa, none were host‐specific, Dicrocoeliidae and Cestoda prevalences differed between host species, Prosthenorchis and Strongylida were the most prevalent. Host age was positively associated with Prosthenorchis ova and filariform larva, but negatively with cestode and the Rhabditoidea ova. We detected no differences between expected and observed levels of co‐infection, nor between group size and parasite species richness over 30 group‐years. Logistic models of individual infection status did not identify a sex bias; however, age and species predicted the presence of four and three parasite taxa, respectively, with saddleback tamarins exhibiting higher PSR. Now that we have reliable baseline data for future monitoring of these populations, next steps involve the molecular characterization of these parasites, and exploration of linkages with health parameters.  相似文献   
97.
This investigation represents the first extensive study of the spatial distribution, sources, and potential effects of polycyclic aromatic hydrocarbons (PAHs) in sediments from Lake Manzala, the largest of Egypt's Mediterranean coastal lakes. The concentrations of PAHs (Σ39 components) ranged from 246 to 9910 ng g?1 dry wt., the highest values corresponding to urban hotspots with high anthropogenic input coming from wastewater discharges and combustion activities and decreasing offshore. The levels of PAHs were significantly lower compared to values reported in several coastal/estuarine areas (e.g., in Spain, Italy, USA, and Egypt) receiving substantial anthropogenic inputs from urban and industrial activities. Source ratios indicated that the PAHs were mainly from petrogenic sources in near-shore urban hotspots, with higher contributions of pyrolytic sources in coastal and offshore areas which are little influenced by human activities. Sediment quality guidelines (SQGs) showed that except at one station heavily impacted by sewage discharge, the total and individual PAH concentrations were below effect range low (ERL) concentrations that are not likely to adversely affect benthic biota.  相似文献   
98.
Toxoplasma gondii is an intracellular protozoan parasite, which relies on a specialized compartment, the parasitophorous vacuole (PV), to survive within host cells. Dense granules within the parasite release a large variety of proteins to maintain the integrity of the vacuole structure. Here, we identified a novel dense granule protein in T. gondii, TgGRA23, which is a homolog of the Sarcocystis muris dense granule protein, SmDG32. Recombinant TgGRA23 (rTgGRA23) expressed in Escherichia coli as a glutathione S-transferase (GST) fusion protein was used to raise antisera in mice and rabbits. Immunoblotting showed that antisera from the immunized mice and rabbits reacted with parasite lysates to yield a 21-kDa native protein. In addition, immuno-electron microscopic examination showed that TgGRA23 resides in the dense granules, PV membrane and intravacuolar network of the parasite. To confirm the precise subcellular localization of TgGRA23 in T. gondii, an immunofluorescent antibody test was performed using dense granule markers. Notably, TgGRA23 co-localized with other dense granule proteins including TgGRA4 and TgGRA7, in the extracellular-stage parasites. Biochemical experiments indicated that TgGRA23 is insoluble and may form an electrostatic complex that is resistant to non-ionic detergents. Furthermore, specific antibodies to TgGRA23 were detected during the chronic stage of Toxoplasma infection in mice. Our results suggest that TgGRA23 is an as yet unknown member of the T. gondii dense granule proteins, and that it may be involved in remodeling or maintenance of the PV.  相似文献   
99.
Abstract

Cyclic imides containing 3-benzenesulfonamide, oxime, and β-phenylalanine derivatives were synthesised and evaluated to elucidate their in vivo anti-inflammatory and ulcerogenic activity and in vitro cytotoxic effects. Most active anti-inflammatory agents were subjected to in vitro COX-1/2 inhibition assay. 3-Benzenesulfonamides (2–4, and 9), oximes (11–13), and β-phenylalanine derivative (18) showed potential anti-inflammatory activities with 71.2–82.9% oedema inhibition relative to celecoxib and diclofenac (85.6 and 83.4%, respectively). Most active cyclic imides 4, 9, 12, 13, and 18 possessed ED50 of 35.4–45.3?mg kg?1 relative to that of celecoxib (34.1?mg kg?1). For the cytotoxic evaluation, the selected derivatives 2–6 and 8 exhibited weak positive cytotoxic effects (PCE = 2/59–5/59) at 10?μM compared to the standard drug, imatinib (PCE = 20/59). Cyclic imides bearing 3-benzenesulfonamide (2–5, and 9), acetophenone oxime (11–14, 18, and 19) exhibited high selectivity against COX-2 with SI > 55.6–333.3 relative to that for celecoxib [SI > 387.6]. β-Phenylalanine derivatives 21–24 and 28 were non-selective towards COX-1/2 isozymes as indicated by their SI of 0.46–0.68.  相似文献   
100.
Abstract

Inhibitory action of newly synthesised 4-(2-(2-substituted-thio-4-oxoquinazolin-3(4H)-yl)ethyl)benzenesulfonamides compounds 2–13 against human carbonic anhydrase (CA, EC 4.2.1.1) (hCA) isoforms I, II, IX, and XII, was evaluated. hCA I was efficiently inhibited by compounds 2–13 with inhibition constants (KIs) ranging from 57.8–740.2?nM. Compounds 2, 3, 4, and 12 showed inhibitory action against hCA II with KIs between 6.4 and 14.2?nM. CA IX exhibited significant sensitivity to inhibition by derivatives 2–13 with KI values ranging from 7.1 to 93.6?nM. Compounds 2, 3, 4, 8, 9, and 12 also exerted potent inhibitory action against hCA XII (KIs ranging from 3.1 to 20.2?nM). Molecular docking studies for the most potent compounds 2 and 3 were conducted to exhibit the binding mode towards hCA isoforms as a promising step for SAR analyses which showed similar interaction with co-crystallized ligands. As such, a subset of these mercaptoquinazolin-4(3H)-one compounds represented interesting leads for developing new efficient and selective carbonic anhydrase inhibitors (CAIs) for the management of a variety of diseases including glaucoma, epilepsy, arthritis and cancer.  相似文献   
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