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281.
Background
Hemolymph plays key roles in honey bee molecule transport, immune defense, and in monitoring the physiological condition. There is a lack of knowledge regarding how the proteome achieves these biological missions for both the western and eastern honey bees (Apis mellifera and Apis cerana). A time-resolved proteome was compared using two-dimensional electrophoresis-based proteomics to reveal the mechanistic differences by analysis of hemolymph proteome changes between the worker bees of two bee species during the larval to pupal stages.Results
The brood body weight of Apis mellifera was significantly heavier than that of Apis cerana at each developmental stage. Significantly, different protein expression patterns and metabolic pathways were observed in 74 proteins (166 spots) that were differentially abundant between the two bee species. The function of hemolymph in energy storage, odor communication, and antioxidation is of equal importance for the western and eastern bees, indicated by the enhanced expression of different protein species. However, stronger expression of protein folding, cytoskeletal and developmental proteins, and more highly activated energy producing pathways in western bees suggests that the different bee species have developed unique strategies to match their specific physiology using hemolymph to deliver nutrients and in immune defense.Conclusions
Our disparate findings constitute a proof-of-concept of molecular details that the ecologically shaped different physiological conditions of different bee species match with the hemolymph proteome during the brood stage. This also provides a starting point for future research on the specific hemolymph proteins or pathways related to the differential phenotypes or physiology.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-563) contains supplementary material, which is available to authorized users. 相似文献282.
Jutta Wiese Usama Ramadan Abdelmohsen Asa Motiei Ute Hentschel Humeida Johannes F. Imhoff 《Bioorganic & medicinal chemistry letters》2018,28(4):558-561
A new cyclic hexapeptide, cyclo-(Gly-Leu-Val-IIe-Ala-Phe), named bacicyclin (1), was isolated from a marine Bacillus sp. strain associated with Mytilus edulis. The sequences of the amino acid building blocks of the cyclic peptide and its structure were determined by 1D- and 2D-NMR techniques. Marfey’s analysis showed that the amino acid building blocks had L-configuration in all cases except for alanine and phenylalanine, which had D-configuration. Bacicyclin (1) exhibited antibacterial activity against the clinically relevant strains Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentration values of 8 and 12?µM, respectively. These results demonstrate the potential of marine bacteria as a promising source for the discovery of new antibiotics. 相似文献
283.
Waleed A. Mohamed Mona F. Schaalan Basma Ramadan 《Journal of cellular biochemistry》2019,120(8):13464-13477
Deregulation of noncoding RNAs, microRNAs (miRNAs) and long noncoding RNA (lncRNA), are implicated in the initiation and progression of gastric cancer (GC). This study is a pilot case-control study carried out on 75 subjects, 40 of them were Helicobacter pylori-gastric ulcer patients and 35 were GC patients recruited from the Gastrointestinal Endoscopy Unit in Al-Kasr Al-Aini Hospital, Cairo University in Egypt. Real-time PCR was performed to evaluate the expression level of serum miR-204, miR-182, and lncRNA H19 in patients with peptic ulcer-progressed GC vs nonprogressed peptic ulcer patients. Fibroblast growth factor 18 (FGF-18)/FGF receptor 2 (FGFR2) expression and their downstream immunological and inflammatory signaling markers were assessed and their association with the addressed noncoding RNAs investigated. As regards miR-204 and miR-182, they were significantly increased (12.5 and 2.6 folds, respectively) in GU samples, compared with those of healthy control levels. The elevated levels of these miRNAs were significantly de-escalated in GC samples compared with GU and the fold decrease valued 2.2 fold for miR-204 and 1.8 folds for miR-182. On the other hand, the significant escalation in the level of lnRNA H19 in GU recorded a 16.6 fold increase and further elevation in its levels was evident in GC samples. The herein assessed miRNAs are correlated with disease duration and FGFR2 with miR-182 being significantly correlated with all inflammatory markers, TAC, INF-γ, matrix metallopeptidase 9, and FGF-18. In terms of diagnostic accuracy of assessed miRNAs (stages III to IV), the receiver operating characteristic analysis indicated that serum lncRNA H19 showed the highest diagnostic accuracy (95.5%), specificity (100%), and sensitivity (90.9%), compared with miR-204 and miR-182, which showed the same specificity (60%), sensitivity (72.7%), and diagnostic accuracy (68.8%). Our findings conclude that lnRNA H19, miR-204, and miR-182 may function as novel prospective plasma biomarkers to detect GC and its progression from H. pylori-peptic ulcer, which would be helpful to improve the theranostics of GC. 相似文献
284.
Emad Ramadan Michael Ward Xin Guo Sarah S Durkin Adam Sawyer Marcelo Vilela Christopher Osgood Alex Pothen Oliver J Semmes 《Retrovirology》2008,5(1):1-13
Background
Unlike CD4+ T cells, HIV-1 infected macrophages exhibit extended life span even upon stress, consistent with their in vivo role as long-lived HIV-1 reservoirs.Results
Here, we demonstrate that PI3K/Akt inhibitors, including clinically available Miltefosine, dramatically reduced HIV-1 production from long-living virus-infected macrophages. These PI3K/Akt inhibitors hyper-sensitize infected macrophages to extracellular stresses that they are normally exposed to, and eventually lead to cell death of infected macrophages without harming uninfected cells. Based on the data from these Akt inhibitors, we were able to further investigate how HIV-1 infection utilizes the PI3K/Akt pathway to establish the cytoprotective effect of HIV-1 infection, which extends the lifespan of infected macrophages, a key viral reservoir. First, we found that HIV-1 infection activates the well characterized pro-survival PI3K/Akt pathway in primary human macrophages, as reflected by decreased PTEN protein expression and increased Akt kinase activity. Interestingly, the expression of HIV-1 or SIV Tat is sufficient to mediate this cytoprotective effect, which is dependent on the basic domain of Tat – a region that has previously been shown to bind p53. Next, we observed that this interaction appears to contribute to the downregulation of PTEN expression, since HIV-1 Tat was found to compete with PTEN for p53 binding; this is known to result in p53 destabilization, with a consequent reduction in PTEN protein production.Conclusion
Since HIV-1 infected macrophages display highly elevated Akt activity, our results collectively show that PI3K/Akt inhibitors may be a novel therapy for interfering with the establishment of long-living HIV-1 infected reservoirs. 相似文献285.
Ali Hebeish Mohamed Hashem Nihal Shaker Mohamed Ramadan Bahiya El-Sadek Marwa Abdel Hady 《Carbohydrate polymers》2009,78(4):953-960
Four different types of cotton-based fabrics, namely, loom-state cotton, cotton/polyester (50/50), cotton/polyester (35/65) and grey mercerized fabrics were bioscoured and bleached. The four substrates are given enzymatic treatment using cellulase enzyme to affect bio-polishing followed by crosslinking using N,N-dimethylol 4,5-dihydroxyethylene urea (DMDHEU) to affect easy care finishing. In another series of experiments the said bioscoured–bleached substrates were similarly crosslinked followed by bio-polishing. Technical properties of the treated fabric that were monitored include: nitrogen content, loss in fabric weight, tensile strength, elongation at break, tear strength, whiteness index, surface roughness and wrinkle recovery angle. Scanning electron micrograph was also examined. Conclusions arrived at from these studies indicated that: post-crosslinking and pre-crosslinking revealed marginal differences in N%, wrinkle recovery angle and whiteness index, a point which validates the argument that cellulase enzyme could not break down the DMDHEU crosslinks within the molecular structure of cotton-containing fabrics. Meanwhile the surface roughness obtained with pre-crosslinking is a bit higher than those of post-crosslinking. Moreover, post-crosslinking caused higher losses in strength properties than pre-crosslinking. Scanning electron micrograph shows that cotton sample pre-crosslinked is almost smooth than those post-crosslinked. 相似文献
286.
Ramadan A. Ali Christina Camick Katherine Wiles Timothy F. Walseth James T. Slama Sumit Bhattacharya David R. Giovannucci Katherine A. Wall 《The Journal of biological chemistry》2016,291(9):4503-4522
Nicotinic acid adenine dinucleotide phosphate (NAADP), the most potent Ca2+ mobilizing second messenger discovered to date, has been implicated in Ca2+ signaling in some lymphomas and T cell clones. In contrast, the role of NAADP in Ca2+ signaling or the identity of the Ca2+ stores targeted by NAADP in conventional naive T cells is less clear. In the current study, we demonstrate the importance of NAADP in the generation of Ca2+ signals in murine naive T cells. Combining live-cell imaging methods and a pharmacological approach using the NAADP antagonist Ned-19, we addressed the involvement of NAADP in the generation of Ca2+ signals evoked by TCR stimulation and the role of this signal in downstream physiological end points such as proliferation, cytokine production, and other responses to stimulation. We demonstrated that acidic compartments in addition to the endoplasmic reticulum were the Ca2+ stores that were sensitive to NAADP in naive T cells. NAADP was shown to evoke functionally relevant Ca2+ signals in both naive CD4 and naive CD8 T cells. Furthermore, we examined the role of this signal in the activation, proliferation, and secretion of effector cytokines by Th1, Th2, Th17, and CD8 effector T cells. Overall, NAADP exhibited a similar profile in mediating Ca2+ release in effector T cells as in their counterpart naive T cells and seemed to be equally important for the function of these different subsets of effector T cells. This profile was not observed for natural T regulatory cells. 相似文献
287.
288.
A new PGE2 derivative (16-phenoxy PGE2 methyl sulfonylamide sulprostone) was administered by the i.m. route to 48 women pregnancy in any of the three trimesters. The indications for pregnancy interruption were either serious medical problems in intact pregnancies (21 cases) or due to fetal death in utero (27 cases). Single doses of 500 micrograms were repeated every 4 hours in the former group or every 6 hours in the latter category for a maximum period of 24 hours. The treatment was successful in 81% of intact pregnancies and in 92.6% of fetal death cases with an overall mean induction interval of 12.9 hours. More than half the subjects did not experience any side effects apart from mild or moderate uterine colics. An overall mean of 1.4 episodes of vomiting or diarrhoea per induction trial was quite acceptable from the clinical point of view. The absence of serious complications in the group of critically sick women speaks in favor of the relative safety of the drug. 相似文献
289.
290.