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111.
112.
Rania Helmy Abd El-Hameed Amira Ibrahim Sayed Shima Mahmoud Ali Mohamed A. Mosa Zainab M. Khoder Samar Said Fatahala 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):2183
Pyrroles and its fused forms possess antimicrobial activities, they can easily interact with biomolecules of living systems. A series of substituted pyrroles, and its fused pyrimidines and triazines forms have been synthesised, all newly synthesised compound structures were confirmed by spectroscopic analysis. Generally, the compounds inhibited growth of some important human pathogens, the best effect was given by: 2a, 3c, 4d on Gram-positive bacteria and was higher on yeast (C. albicans), by 5c on Gram-negative bacteria and by 5a then 3c on filamentous fungi (A. fumigatus and F. oxysporum). Such results present good antibacterial and antifungal potential candidates to help overcome the global problem of antibiotic resistance and opportunistic infections outbreak. Compound 3c gave the best anti-phytopathogenic effect at a 50-fold lower concentration than Kocide 2000, introducing a safe commercial candidate for agricultural use. The effect of the compounds on DNA was monitored to detect the mode of action. 相似文献
113.
Jeanne d’Arc AlBacha Mira Khoury Charbel Mouawad Katia Haddad Samar Hamoui Albert Azar Ziad Fajloun Nehman Makdissy 《PloS one》2015,10(5)
Cardiovascular diseases (CVDs) are significantly high in the Lebanese population with the two most predominant forms being atherosclerosis and venous thrombosis. The purpose of our study was to assess the association of a spectrum of CVD related genes and combined state of hypertension hypercholesterolemia (HH) in unrelated Lebanese. Twelve polymorphisms were studied by multiplex PCR and reverse hybridization of DNA from 171 healthy individuals and 144 HH subjects. Two genes were significantly associated with HH: ACE (OR: 9.20, P<0.0001) and PAI-1 (OR: 2.29, P = 0.007), respectively with the occurrence of the risky alleles “Del” and “4G”. The frequencies of the Del and 4G alleles were found to be 0.98 and 0.90 in the HH group versus 0.84 and 0.79 in the healthy group, respectively. Serum ACE activity and PAI-I increased significantly with Del/Del and 4G/5G genotypes. The co-expression of Del/4G(+/+) was detected in 113 out of 171 (66.0%) controls and 125 out of 144 (86.8%) HH subjects. Del/4G(-/-) was detected in only 6 (3.5%) controls and undetected in the HH group. Three venous thrombosis related genes [FV(Leiden), MTHFR(A1298C) and FXIII(V34L)] were significantly related to the prominence of the co-expression of Del/4G(+/+). A range of 2 to 8 combined polymorphisms co-expressed per subject where 5 mutations were the most detected. In Del/4G(+/+) subjects, peripheral blood mononuclear cells (PBMCs) produced significant elevated levels of IFN-γ and TNF-α contrary to IL-10, and no variations occurred for IL-4. ACE inhibitor (ramipril) in combination with statin (atorvastatin) and not alone reversed significantly the situation. This first report from Lebanon sheds light on an additional genetic predisposition of a complex spectrum of genes involved in CVD and suggests that the most requested gene FVL by physicians may not be sufficient to diagnose eventual future problems that can occur in the cardiovascular system. Subjects expressing the double mutations (Del/4G) are at high risk for the onset of CVDs. 相似文献
114.
Acid phosphatase activity was studied in the left and right ovaries of the chick during embryonic development. The cytochemical study indicated that local enzymatic activity is localized mainly in germ and somatic cells. From the results obtained in the study on the specific activity of this acid hydrolase, it can be inferred that the higher concentration of this enzyme in the right ovary would be determined by a decrease of total proteins in the total homogenate and in the cellular fractions of this organ. Besides, a decrease in the enzymatic activity of this ovary is not observed, but it occurs in the left ovary. This finding would indicate a lack of enzymatic segregation that could be related to the phenomenon of ovarian atrophy. Finally, the electrophoretic study indicated that it would apparently exist only one molecular form of the enzyme. Our results support the hypothesis that acid phosphatase would be involved in the atrophic processes of the right ovary during embryonary differentiation. 相似文献
115.
Samar Basu Kristell Combe Fabrice Kwiatkowski Florence Caldefie-Chézet Frédérique Penault-Llorca Yves-Jean Bignon Marie-Paule Vasson 《PloS one》2015,10(10)
Current evidences suggest that expression of Ki67, cyclooxygenase (COX), aromatase, adipokines, prostaglandins, free radicals, β-catenin and α-SMA might be involved in breast cancer pathogenesis. The main objective of this study was to compare expression/localization of these potential compounds in breast cancer tissues with tissues collected adjacent to the tumor using immunohistochemistry and correlated with clinical pathology. The breast cancer specimens were collected from 30 women aged between 49 and 89 years who underwent breast surgery following cancer diagnosis. Expression levels of molecules by different stainings were graded as a score on a scale based upon staining intensity and proportion of positive cells/area or individually. AdipoR1, adiponectin, Ob-R, leptin, COX-1, COX-2, aromatase, PGF2α, F2-isoprostanes and α-SMA were localised on higher levels in the breast tissues adjacent to the tumor compared to tumor specimens when considering either score or staining area whereas COX-2 and AdipoR2 were found to be higher considering staining intensity and Ki67 on score level in the tumor tissue. There was no significant difference observed on β-catenin either on score nor on staining area and intensity between tissues adjacent to the tumor and tumor tissues. A positive correlation was found between COX-1 and COX-2 in the tumor tissues. In conclusion, these suggest that Ki67, COXs, aromatase, prostaglandin, free radicals, adipokines, β-catenin and α-SMA are involved in breast cancer. These further focus the need of examination of tissues adjacent to tumor, tumor itself and compare them with normal or benign breast tissues for a better understanding of breast cancer pathology and future evaluation of therapeutic benefit. 相似文献
116.
Amaly Nokkari Tarek H. Mouhieddine Muhieddine M. Itani Wassim Abou-Kheir Georges Daoud Rui Zhu Yehia Meshref Jihane Soueid Moustafa Al Hariri Stefania Mondello Ayad A. Jaffa Firas Kobeissy 《PloS one》2015,10(6)
Traumatic Brain Injury (TBI) is the result of a mechanical impact on the brain provoking mild, moderate or severe symptoms. It is acknowledged that TBI leads to apoptotic and necrotic cell death; however, the exact mechanism by which brain trauma leads to neural injury is not fully elucidated. Some studies have highlighted the pivotal role of the Kallikrein-Kinin System (KKS) in brain trauma but the results are still controversial and inconclusive. In this study, we investigated both the expression and the role of Bradykinin 1 and 2 receptors (B1R and B2R), in mediating neuronal injury under chemical neurotoxicity paradigm in PC12 cell lines. The neuronal cell line PC12 was treated with the apoptotic drug Staurosporine (STS) to induce cell death. Intracellular calcium release was evaluated by Fluo 4-AM staining and showed that inhibition of the B2R prevented calcium release following STS treatment. Differential analyses utilizing immunofluorescence, Western blot and Real-time Polymerase Chain Reaction revealed an upregulation of both bradykinin receptors occurring at 3h and 12h post-STS treatment, but with a higher induction of B2R compared to B1R. This implies that STS-mediated apoptosis in PC12 cells is mainly conducted through B2R and partly via B1R. Finally, a neuroproteomics approach was conducted to find relevant proteins associated to STS and KKS in PC12 cells. Neuroproteomics results confirmed the presence of an inflammatory response leading to cell death during apoptosis-mediated STS treatment; however, a “survival” capacity was shown following inhibition of B2R coupled with STS treatment. Our data suggest that B2R is a key player in the inflammatory pathway following STS-mediated apoptosis in PC12 cells and its inhibition may represent a potential therapeutic tool in TBI. 相似文献
117.
Baligh R. Yehia Alisa J. Stephens-Shields John A. Fleishman Stephen A. Berry Allison L. Agwu Joshua P. Metlay Richard D. Moore W. Christopher Mathews Ank Nijhawan Richard Rutstein Aditya H. Gaur Kelly A. Gebo HIV Research Network 《PloS one》2015,10(6)
Background
The HIV care continuum (diagnosis, linkage to care, retention in care, receipt of antiretroviral therapy (ART), viral suppression) has been used to identify opportunities for improving the delivery of HIV care. Continuum steps are typically calculated in a conditional manner, with the number of persons completing the prior step serving as the base population for the next step. This approach may underestimate the prevalence of viral suppression by excluding patients who are suppressed but do not meet standard definitions of retention in care. Understanding how retention in care and viral suppression interact and change over time may improve our ability to intervene on these steps in the continuum.Methods
We followed 17,140 patients at 11 U.S. HIV clinics between 2010-2012. For each calendar year, patients were classified into one of five categories: (1) retained/suppressed, (2) retained/not-suppressed, (3) not-retained/suppressed, (4) not-retained/not-suppressed, and (5) lost to follow-up (for calendar years 2011 and 2012 only). Retained individuals were those completing ≥2 HIV medical visits separated by ≥90 days in the year. Persons not retained completed ≥1 HIV medical visit during the year, but did not meet the retention definition. Persons lost to follow-up had no HIV medical visits in the year. HIV viral suppression was defined as HIV-1 RNA ≤200 copies/mL at the last measure in the year. Multinomial logistic regression was used to determine the probability of patients’ transitioning between retention/suppression categories from 2010 to 2011 and 2010 to 2012, adjusting for age, sex, race/ethnicity, HIV risk factor, insurance status, CD4 count, and use of ART.Results
Overall, 65.8% of patients were retained/suppressed, 17.4% retained/not-suppressed, 10.0% not-retained/suppressed, and 6.8% not-retained/not-suppressed in 2010. 59.5% of patients maintained the same status in 2011 (kappa=0.458) and 53.3% maintained the same status in 2012 (kappa=0.437).Conclusions
Not counting patients not-retained/suppressed as virally suppressed, as is commonly done in the HIV care continuum, underestimated the proportion suppressed by 13%. Applying the care continuum in a longitudinal manner will enhance its utility. 相似文献118.
Saurabh Chattopadhyay Manoj Veleeparambil Darshana Poddar Samar Abdulkhalek Sudip K Bandyopadhyay Volker Fensterl Ganes C Sen 《EMBO reports》2015,16(11):1535-1547
Mammalian Toll-like receptors (TLR) recognize microbial products and elicit transient immune responses that protect the infected host from disease. TLR4—which signals from both plasma and endosomal membranes—is activated by bacterial lipopolysaccharides (LPS) and induces many cytokine genes, the prolonged expression of which causes septic shock in mice. We report here that the expression of some TLR4-induced genes in myeloid cells requires the protein kinase activity of the epidermal growth factor receptor (EGFR). EGFR inhibition affects TLR4-induced responses differently depending on the target gene. The induction of interferon-β (IFN-β) and IFN-inducible genes is strongly inhibited, whereas TNF-α induction is enhanced. Inhibition is specific to the IFN-regulatory factor (IRF)-driven genes because EGFR is required for IRF activation downstream of TLR—as is IRF co-activator β-catenin—through the PI3 kinase/AKT pathway. Administration of an EGFR inhibitor to mice protects them from LPS-induced septic shock and death by selectively blocking the IFN branch of TLR4 signaling. These results demonstrate a selective regulation of TLR4 signaling by EGFR and highlight the potential use of EGFR inhibitors to treat septic shock syndrome. 相似文献
119.
Yong Li Christine Fink Samar El‐Kholy Thomas Roeder 《Archives of insect biochemistry and physiology》2015,88(3):168-178
The biogenic monoamine octopamine is essential for ovulation and fertilization in insects. Release of this hormone from neurons in the thoracoabdominal ganglion triggers ovulation and sperm release from the spermathecae. Here we show that the effects of octopamine on ovulation are mediated by at least two different octopamine receptors. In addition to the Oamb receptor that is present in the epithelium of the oviduct, the octß2R receptor is essential for ovulation and fertilization. Octß2R is widely expressed in the female reproductive tract. Most prominent is expression in the oviduct muscle and the spermathecae. Animals deficient in expression of the receptor show a severe egg‐laying defect. The corresponding females have a much larger ovary that is caused by egg retention in the ovary. Moreover, the very few laid eggs are not fertilized, indicating problems in the process of sperm delivery. We assume that octß2R acts in a similar way as ß2‐adrenoreceptors in smooth muscles, were activation of this receptor induces an increase in cAMP levels that lead to relaxation of the muscle. Taken together, our findings show that octopaminergic control of ovulation and fertilization is more complex than anticipated and that various receptors located in different cells act together to enable a well‐orchestrated activity of the female reproductive system in response to copulation. 相似文献
120.
Sameh E. Hassanien Ahmed M. Ramadan Ahmed Z. Abdel Azeiz Rasha A. Mohammed Sabah M. Hassan Ahmed M. Shokry Ahmed Atef Khalid B.H. Kamal Samar Rabah Jamal S.M. Sabir Osama A. Abuzinadah Fotouh M. El-Domyati Gregory B. Martin Ahmed Bahieldin 《Comptes rendus biologies》2013,336(11-12):546-556
Thymoquinone (TQ) is a major constituent of Nigella sativa oil with reported anti-oxidative activity and anti-inflammatory activity in animal cells. It also inhibits proliferation and induces programmed cell death (apoptosis) in human skin cancer cells. The present study sought to detect the influence of TQ on dividing cells of three plant systems and on expression of Bcl2-associated athanogene-like (BAG-like) genes that might be involved during the process of cell death. BAG genes are known for the regulation of diverse physiological processes in animals, including apoptosis, tumorigenesis, stress responses, and cell division. Synthetic TQ at 0.1 mg/mL greatly reduced wheat seed germination rate, whereas 0.2 mg/mL completely inhibited germination. An Evans blue assay revealed moderate cell death in the meristematic zone of Glycine max roots after 1 h of TQ treatment (0.2 mg/mL), with severe cell death occurring in this zone after 2 h of treatment. Light microscopy of TQ-treated (0.2 mg/mL) onion hairy root tips for 1 h revealed anti-mitotic activity and also cell death-associated changes, including nuclear membrane disruption and nuclear fragmentation. Transmission electron microscopy of TQ-treated cells (0.2 mg/mL) for 1 h revealed shrinkage of the plasma membrane, leakage of cell lysate, degradation of cell walls, enlargement of vacuoles and condensation of nuclei. Expression of one BAG-like gene, previously associated with cell death, was induced 20 min after TQ treatment in Glycine max root tip cells. Thus, TQ has multiple effects, including cell death, on dividing plant cells and plants may serve as a useful system to further investigate the mechanisms underlying the response of eukaryotic cells to TQ. 相似文献