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51.
Alaa Shaheen 《Cell stress & chaperones》2018,23(5):797-806
The unfolded protein response (UPR) is an adaptive cellular response that aims to relieve endoplasmic reticulum (ER) stress via several mechanisms, including inhibition of protein synthesis and enhancement of protein folding and degradation. There is a controversy over the effect of the UPR on ER protein export. While some investigators suggested that ER export is inhibited during ER stress, others suggested the opposite. In this article, their conflicting studies are analyzed and compared in attempt to solve this controversy. The UPR appears indeed to enhance ER export, possibly via multiple mechanisms. However, another factor, which is the integrity of the folding machinery/environment inside ER, determines whether ER export will appear increased or decreased during experimentation. Also, different methods of stress induction appear to have different effects on ER export. Thus, improvement of ER export may represent a new mechanism by which the UPR alleviates ER stress. This may help researchers to understand how the UPR works inside cells and how to manipulate it to alter cell fate during stress, either to promote cell survival or death. This may open up new approaches for the treatment of ER stress-related diseases. 相似文献
52.
Alaa Elkordy Eikan Mishima Kuniyasu Niizuma Yasutoshi Akiyama Miki Fujimura Teiji Tominaga Takaaki Abe 《Journal of neurochemistry》2018,146(5):560-569
53.
Faten Zahran Alaa Mohamad Nabila Zein 《Experimental biology and medicine (Maywood, N.J.)》2021,246(24):2630
High levels of blood glucose and lipids are well-known risk factors for heart diseases. Bee venom is a natural product that has a potent hypoglycemic, hypolipidemic, anti-inflammatory, and antioxidant effects. The current study aimed to determine the bee venom effects on cardiac dysfunction compared to combined therapy of metformin and atorvastatin in diabetic hyperlipidemic rats. The median lethal dose of bee venom was estimated, and then 50 adult male albino rats were categorized into five groups. One group was fed a standard diet and served as a negative control, while the other groups were given nicotinamide and streptozotocin injections to induce type 2 diabetes. After confirming diabetes, the rats were fed a high-fat diet for four weeks. The four groups were divided as follows: one group served as a positive control, whereas the other three groups were treated with bee venom (0.5 mg/kg), bee venom (1.23 mg/kg), and combined therapy of metformin (60 mg/kg) and atorvastatin (10 mg/kg), respectively, for four weeks. Upon termination of the experiment, blood samples and heart tissue were obtained. Administration of bee venom using both doses (0.5 and 1.23 mg/kg) and combined therapy of metformin and atorvastatin revealed a significant decrease in the concentrations of glucose, total cholesterol, triacylglycerol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, troponin I, creatine kinase, and lactate dehydrogenase activities. Moreover, a significant decrease had been detedcted in malondialdehyde, nuclear factor-kappa-β levels, and relative mRNA expression of vascular cell adhesion molecule-1 and galectin-3 in heart tissue compared to the positive control (P < 0.0001). Furthermore, there was a significant increase in bodyweight levels of insulin, high-density lipoprotein cholesterol, and total antioxidant capacity in heart tissue compared to the positive control (P < 0.0001). The results indicate that bee venom can ameliorate cardiac dysfunction through attenuating oxidative stress and downregulating the NF-κβ signaling pathway. 相似文献
54.
Samia Hussein Hala Mosaad Hayam E. Rashed Shimaa Ahmed Ahmed Ragab Eman I. Ismail 《Molecular biology reports》2017,44(4):365-377
This study aimed to assess the expression of S100A4, Twist and E-cadherin (mRNA and protein) in urothelial bladder cancer, investigate the correlation between them and evaluate their association with the clinicopathological features of the disease. The study included 54 patients diagnosed as urothelial bladder cancer of different stages and grades. The expression levels of S100A4, Twist and E-cadherin (mRNA and protein) in tissue samples were determined by quantitative RT-PCR and immunohistochemistry. The expression of S100A4 and Twist was significantly upregulated while E- cadherin was significantly downregulated in urothelial bladder cancer tissues compared to the adjacent surrounding normal bladder tissues at both mRNA and protein levels (p?<?0.001). Expression levels of S100A4 and Twist were significantly higher in recurrent tumor than in non-recurrent tumors (p?<?0.001) while the expression level of E-cadherin was significantly lower in recurrent tumors than in non-recurrent tumors at both mRNA and protein levels (p?<?0.001). There was a significant positive correlation between S100A4 and Twist expressions (r?=?0.875, p?<?0.001) while significant negative correlations were found between E- cadherin and S100A4 expressions(r=- 0.803, p?<?0.001) and between E-cadherin and Twist (r?=??0.809, p?<?0.001). Up-regulation of S100A4 and Twist and down-regulation of E-cadherin in urothelial bladder cancer tissues compared to adjacent normal tissues were observed. There was a significant negative correlation between S100A4 and E- cadherin and between E- cadherin and Twist expression. However, there was a significant positive correlation between S100A4 and Twist expressions. Furthermore, the alterations in the gene expression were associated with disease stage and grade. 相似文献
55.
Alaa Al-Seraih Yanath Belguesmia John Baah Sabine Szunerits Rabah Boukherroub Djamel Drider 《Antonie van Leeuwenhoek》2017,110(2):205-219
Enterococcus faecalis B3A-B3B produces the bacteriocin B3A-B3B with activity against Listeria monocytogenes, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium perfringens, but apparently not against fungi or Gram-negative bacteria, except for Salmonella Newport. B3A-B3B enterocin has two different nucleotides but similar amino acid composition to the class IIb MR10A-MR10B enterocin. B3A-B3B consists of two peptides of predicted molecular mass of 5176.31 Da (B3A) and 5182.21 Da (B3B). Importantly, B3A-B3B impeded biofilm formation of the foodborne pathogen L. monocytogenes 162 grown on stainless steel. The antimicrobial treatment of stainless steel with nisin (1 or 16 mg ml?1) decreased the cell numbers by about 2 log CFU ml?1, thereby impeding the biofilm formation by L. monocytogenes 162 or its nisin-resistant derivative strain L. monocytogenes 162R. Furthermore, the combination of nisin and B3A-B3B enterocin reduced the MIC required to inhibit this pathogen grown in planktonic or biofilm cultures. 相似文献
56.
Amash A Holcberg G Sheiner E Fleisher-Berkovich S Myatt L Huleihel M 《Prostaglandins & other lipid mediators》2009,88(1-2):18-22
The aim of the present study was to examine the effect of lipopolysaccharide (LPS) on the levels of prostaglandin E(2) (PGE(2)) in the perfusates of the fetal and the maternal compartments of perfused human term placental tissue. Term placentas were perfused for 10h in the absence [control, (n=4)] and presence of LPS [LPS=1 microg/kg perfused placental tissue, (n=4)] in the maternal reservoir. Perfusate samples from the fetal and the maternal circulations were collected every 30 min and examined for PGE(2) levels by radio-immunoassay. PGE(2) levels in the fetal circulation were gradually increased reaching significant peak value of 479+/-159 pg/ml, as compared to PGE(2) levels in the maternal circulation (140+/-146 pg/ml) (p<0.05). After 10 hours of perfusion with control medium, PGE(2) levels in the maternal circulation (347+/-144 pg/ml) were significantly higher as compared to the fetal circulation (150+/-57 pg/ml) (p<0.05). In presence of LPS, PGE(2) levels in the fetal circulation increased reaching a peak value of 1028+/-663 pg/ml after 240 min of perfusion. The levels of PGE(2) in the control group after 240 min of perfusion were significantly lower (156+/-77 pg/ml) (p<0.05). No significant differences were detected in the levels of PGE(2) in the perfusate of the maternal compartment in presence of LPS, as compared to control. Our results suggest that the placenta may play an important role in maintaining high levels of PGE(2) in the fetal circulation and low PGE(2) levels in the maternal circulation during normal pregnancy. Moreover, placental PGE(2) release into the fetal and the maternal circulations may be differently affected in presence of intra-uterine infection/inflammation. 相似文献
57.
C. Abdul JALEEL Changxing ZHAO Sedghi MOHAMED Hameed Jasim AL-JUBURI Helal Ragab MOUSSA M. GOMATHINAYAGAM R. PANNEERSELVAM 《生物学前沿》2009,4(4)
Changes in the sucrose metabolism of Cur-cuma longa L. plants were studied under treatment with different triazole compounds viz., triadimefon (TDM) and propiconazole (PCZ). Plants were treated with TDM at 15 mg/L and PCZ at 10 mg/L separately by soil drenching on 80, 110, and 140 days after planting (DAP). The plants were harvested randomly on 90, 120, and 150DAP to determine the effect of both the triazoles on sucrose metabolizing enzymes and phenol content. The sucrose metabolism was studied by analyzing sucrose metaboliz-ing enzymes like sucrose synthase and sucrose phosphate synthase. All the analyses were assayed in leaves and tubers of both control and treated plants. It was found that both of the triazole compounds had profound effects on these parameters. 相似文献
58.
Spectrofluorometric determination of clonazepam in dosage forms: Application to content uniformity testing and human plasma
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The present paper describes a developed and validated simple, highly sensitive and cost‐effective spectrofluorometric method for determination of clonazepam (CNP). The proposed method depends on forming a highly fluorescent product through the reduction of CNP with Zn/HCl. The produced fluorophore exhibits a strong fluorescence at λem 350 nm after excitation at λex 250 nm. The use of carboxymethylcellulose (CMC) greatly enhanced the fluorescence intensity of the produced fluorophore to the extent of about 100%. Calibration curve showed good linear regression (r 2 > 0.9998) within test ranges of 20–400 ng ml?1 with a lower detection limit of 0.67 ng ml?1 and lower quantification limit of 2.22 ng ml?1 upon using CMC. The method was successfully applied to the analysis of CNP in its pharmaceutical formulations and the results were in agreement with those obtained using a reference method. Furthermore, the content uniformity testing of the tablets was also performed. The application of the proposed method was extended to determine CNP in spiked human plasma sample as a preliminary investigation and the results were satisfactory. 相似文献
59.
Mohammed M. Alanazi Elwan Alaa Nawaf A. Alsaif Ahmad J. Obaidullah Hamad M. Alkahtani Abdulrahman A. Al-Mehizia Sultan M. Alsubaie Mohammed S. Taghour Ibrahim H. Eissa 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):1732
There is an urgent need to design new anticancer agents that can prevent cancer cell proliferation even with minimal side effects. Accordingly, two new series of 3-methylquinoxalin-2(1H)-one and 3-methylquinoxaline-2-thiol derivatives were designed to act as VEGFR-2 inhibitors. The designed derivatives were synthesised and evaluated in vitro as cytotoxic agents against two human cancer cell lines namely, HepG-2 and MCF-7. Also, the synthesised derivatives were assessed for their VEGFR-2inhibitory effect. The most promising member 11e were further investigated to reach a valuable insight about its apoptotic effect through cell cycle and apoptosis analyses. Moreover, deep investigations were carried out for compound 11e using western-plot analyses to detect its effect against some apoptotic and apoptotic parameters including caspase-9, caspase-3, BAX, and Bcl-2. Many in silico investigations including docking, ADMET, toxicity studies were performed to predict binding affinity, pharmacokinetic, drug likeness, and toxicity of the synthesised compounds. The results revealed that compounds 11e, 11g, 12e, 12g, and 12k exhibited promising cytotoxic activities (IC50 range is 2.1 − 9.8 µM), comparing to sorafenib (IC50 = 3.4 and 2.2 µM against MCF-7 and HepG2, respectively). Moreover, 11b, 11f, 11g, 12e, 12f, 12g, and 12k showed the highest VEGFR-2 inhibitory activities (IC50 range is 2.9 − 5.4 µM), comparing to sorafenib (IC50 = 3.07 nM). Additionally, compound 11e had good potential to arrest the HepG2 cell growth at G2/M phase and to induce apoptosis by 49.14% compared to the control cells (9.71%). As well, such compound showed a significant increase in the level of caspase-3 (2.34-fold), caspase-9 (2.34-fold), and BAX (3.14-fold), and a significant decrease in Bcl-2 level (3.13-fold). For in silico studies, the synthesised compounds showed binding mode similar to that of the reference compound (sorafenib). 相似文献
60.
Cryptosporidium parvum, an intestinal apicomplexan parasite, is a significant cause of diarrheal diseases in both humans and animals. What is more,
there is no promising strategy for controlling cryptosporidiosis. In this study, the P23 immunodominant surface protein of
C. parvum sporozoites was stably expressed in the Lactobacillus casei Zhang strain and its immunogenicity was evaluated in a mouse model. The molecular weight (23 kDa) and immunogenicity of p23
gene expressed by L. casei Zhang were similar to that of the native P23 protein. Oral immunization with control L. casei Zhang and recombinant L. casei Zhang-p23 activated the mucosal immune system to elicit serum immunoglobulin G (IgG) and mucosal IgA in mice. Furthermore,
the expression of cytokines such as IL-4, IL-6, and IFN-γ in splenocytes of mice was detected by real-time PCR after oral
immunization. P23-specific immunocyte activation was also verified. These findings indicate that the live L. casei Zhang vector may be a new tool for the production of mucosal vaccines against cryptosporidiosis in animals. 相似文献