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91.
92.
Amiali NM Mulvey MR Sedman J Simor AE Ismail AA 《Journal of microbiological methods》2007,69(1):146-153
A rapid and simple typing system is needed for controlling the spread of epidemic methicillin-resistant Staphylococcus aureus (MRSA), currently one of the most widespread multi-resistant nosocomial pathogens in Canadian hospitals. Fourier transform infrared (FTIR) spectroscopy was used to subtype 85 isolates representing five strains of epidemic Canadian MRSA (CMRSA). Spectral fingerprints of whole cells grown on Que-Bact(R) Universal Medium No. 2 were transformed to first derivative peak-height normalized files and examined visually and by singular-value decomposition (SVD). Distinguishing spectral regions were processed by principal component analysis (PCA), self-organizing map and K-nearest neighbor supervised cluster analysis. Among the visually identified regions, 1070-1050 and 1155-1137 cm(-1) were found suitable for discrimination of CMRSA-4 and CMRSA-2 respectively, while CMRSA-1, CMRSA-3, and CMRSA-5 each exhibited distinctive spectral profiles in the 1123-1094 cm(-1) region. The combination, 1123-1094, 1174-1154 and 2904-2864 cm(-1) separated the five CMRSA with 84.6% correct classification by PCA. Five clusters were also obtained using the SVD-selected regions 1096-1066, 1118-1090 and 2914-2880 cm(-1), with 87.8% correct classification based on visual examination of the PCA scores plot and 97% based on supervised cluster analysis. These results demonstrate that FTIR spectroscopy has considerable potential as a rapid (1-hour) and simple method for MRSA strain typing and monitoring in clinical settings. 相似文献
93.
Grande F Aiello F Grazia OD Brizzi A Garofalo A Neamati N 《Bioorganic & medicinal chemistry》2007,15(1):288-294
Recently, we discovered a novel class of anticancer compounds with remarkable potency in a panel of cancer cell lines. A prototype compound, SC144, showed significant in vivo efficacy in mice xenograft models of human breast cancer cells. Herein, we report on a new synthetic route to SC144 and the synthesis of several of its analogues in order to understand required features for activity. A one-step coupling of 7-fluoro-4-chloropyrrolo[1,2-a]quinoxaline with pyrazin-2-carbohydrazide improved the yield significantly. Although several of the analogues showed significant activities, modification of the heteroacyl moiety had a dramatic effect on potency. 相似文献
94.
Patil S Kamath S Sanchez T Neamati N Schinazi RF Buolamwini JK 《Bioorganic & medicinal chemistry》2007,15(3):1212-1228
A new series of phenanthridinone derivatives, and diketo acid analogs, as well as related phenanthrene and anthracene diketo acids have been synthesized and evaluated as HIV integrase (IN) inhibitors. Several new beta-diketo acid analogs with the phenanthridinone scaffold replaced by phenanthrene, anthracene or pyrene exhibited the highest IN inhibitory potency. There is a general selectivity against the integrase strand transfer step. The most potent IN was 2,4-dioxo-4-phenanthren-9-yl-butyric acid (27f) with an IC(50) of 0.38microM against integrase strand transfer. The phenanthrene diketo acids 27d-f were more potent (IC(50)=2.7-0.38microM) than the corresponding phenanthridinone diketo acid 16 (IC(50)=65microM), suggesting that the polar amide bridge in the phenanthridinone system decreases inhibitory activity relative to the more lipophilic phenanthrene system. This might have to do with the possible binding of the aryl group of the compounds binding to a lipophilic pocket at the integrase active site as suggested by the docking simulations. Molecular modeling also suggested that effectiveness of chelation of the active site Mg(2+) contributes to IN inhibitory potency. Finally, some of the potent compounds inhibited HIV-1 replication in human peripheral blood mononuclear cells (PBMC) with EC(50) down to 8microM for phenanthrene-3-(2,4-dioxo)butyric acid (27d), with a selectivity index of 10 against PBMCs. 相似文献
95.
Alfredo Diaz-Lara Lynn Wunderlich Mohamed T. Nouri Deborah Golino Maher Al Rwahnih 《Journal of Phytopathology》2022,170(1):15-20
Novel negative-stranded RNA (nsRNA) viruses have been recently identified in multiple agronomic crops, including pome fruit trees. Citrus concave gum-associated virus (CCGaV), citrus virus A (CiVA) and apple rubbery wood viruses 1 and 2 (ARWV1 and 2) are examples of such viruses. Given the novelty and lack of information about these pathogens in Californian orchards, in this study, real-time RT-PCR assays for CCGaV, CiVA, ARWV1 and 2 were developed and employed in a field survey. Initially, the new assays were challenged against a comprehensive set of positive and negative samples, previously analysed by high-throughput sequencing (HTS), to determine specificity. Aiming to investigate the presence of nsRNA viruses in California apple and pear orchards, 186 samples were collected from 21 different locations. As a result, 79 (42%) samples were found to be infected by these viruses in single or mixed infections. The incidence of each virus in relation to the total number of samples was 36%, 15%, 11% and 0% for ARWV2, CCGaV, ARWV1 and CiVA respectively. Overall, not considering the no detected CiVA, the other three nsRNA viruses were widely distributed among sampled orchards. To further validate the reliability of the new real-time RT-PCR assays, six samples tested positive during the survey were screened by previously described detection assays and HTS. This is the first detection of these nsRNA viruses in California, which may represent an issue in apple and pear production. 相似文献
96.
97.
Ali Ranjbaran Zeinab Latifi Hamid Reza Nejabati Sina Abroon Aynaz Mihanfar Aydin Raei Sadigh Amir Fattahi Mohammad Nouri Nathalie Raffel 《Journal of cellular physiology》2019,234(11):19212-19222
Different strategies are applied for cellular cross-talk and organization in multicellular organisms. Exosomes are a homogenous population of biological nanoparticles (30–100 nm), originated from multivesicular bodies. The exosomes (Exos) could regulate and affect both cellular physiology and pathophysiology in various organs, such as the female reproductive tract, by altering gene pathways and/or epigenetic programming. Besides, engineered Exos have the potential to be used as a novel drug and gene delivery tools. Here in this review, we discussed various aspects of exosome-based intercellular communication in female reproductive microenvironments. Furthermore, we addressed the findings and issues related to Exos in reproductive biology to give a better view of the involved molecular mechanisms. Moreover, clinical applications of the Exos and their isolation source/methods have been considered to throw some light on the progression of new biological, diagnostic, and therapeutic approaches in clinical embryology. 相似文献
98.
Stphanie Chacar Joelle Hajal Youakim Saliba Patrick Bois Nicolas Louka Richard G. Maroun Jean‐Franois Faivre Nassim Fares 《Aging cell》2019,18(2)
With the onset of advanced age, cardiac‐associated pathologies have increased in prevalence. The hallmarks of cardiac aging include cardiomyocyte senescence, fibroblast proliferation, inflammation, and hypertrophy. The imbalance between levels of reactive oxygen species (ROS) and antioxidant enzymes is greatly enhanced in aging cells, promoting cardiac remodeling. In this work, we studied the long‐term impact of phenolic compounds (PC) on age‐associated cardiac remodeling. Three‐month‐old Wistar rats were treated for 14 months till middle‐age with either 2.5, 5, 10, or 20 mg kg?1 day?1 of PC. PC treatment showed a dose‐dependent preservation of cardiac ejection fraction and fractional shortening as well as decreased hypertrophy reflected by left ventricular chamber diameter and posterior wall thickness as compared to untreated middle‐aged control animals. Analyses of proteins from cardiac tissue showed that PC attenuated several hypertrophic pathways including calcineurin/nuclear factor of activated T cells (NFATc3), calcium/calmodulin‐dependent kinase II (CAMKII), extracellular regulated kinase 1/2 (ERK1/2), and glycogen synthase kinase 3ß (GSK 3ß). PC‐treated groups exhibited reduced plasma inflammatory and fibrotic markers and revealed as well ameliorated extracellular matrix remodeling and interstitial inflammation by a downregulated p38 pathway. Myocardia from PC‐treated middle‐aged rats presented less fibrosis with suppression of profibrotic transforming growth factor‐ß1 (TGF‐ß1) Smad pathway. Additionally, reduction of apoptosis and oxidative damage in the PC‐treated groups was reflected by elevated antioxidant enzymes and reduced RNA/DNA damage markers. Our findings pinpoint that a daily consumption of phenolic compounds could preserve the heart from the detrimental effects of aging storm. 相似文献
99.
100.
Divya Pathania Mario Sechi Michele Palomba Vanna Sanna Francesco Berrettini Angela Sias Laleh Taheri Nouri Neamati 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014