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Helicobacter pylori is one of the most common human infectious bacteria. The infection is highly associated with a number of the most important disease of the upper gastrointestinal tract, including gastritis, duodenitis, peptic ulceration, and gastric cancer. In addition, widespread use of antimicrobial agents has resulted in the development of antibiotic resistance. Metabolites of plants, particularly higher plants, have been suggested as alternative potential sources for antibacterial products due to their safe. This study aimed to evaluate antibacterial activities of crude ethanolic extracts of seventeen Vietnamese medicinal plants toward one reference strain and three clinical isolates of Helicobacter pylori using broth micro-dilution bioassay. The antibacterial activities of these extracts were also compared with those of seven antibiotics, amoxicillin, clarithromycin, erythromycin, levofloxacin, azithromycin, tetracycline, and metronidazole. The extracts of Ampelopsis cantoniensis and Cleistocalyx operculatus showed highest antibacterial activity with MIC (MBC) values of 0.31 - 0.97 (2.5 - 5) mg/mL, followed by the extracts of Hedyotis diffusa and Ardisia silvestris with MIC (MBC) values of 1.04 - 1.94 (7.5 - 10) mg/mL. The remaining plant extracts exhibited moderate, low and very low or no active to the H. pylori strains. Further studies are needed to determine the active compounds from the extracts that showed high antibacterial activity against H. pylori. [ABSTRACT FROM AUTHOR]

Pattern matching task plays an important role in network security applications especially Network Intrusion Detection System (NIDS). The limitation of matching throughput on general purpose processor gives rise to implementation of the task on FPGA. In this paper, we introduce a memory efficient FPGA-based pattern matching engine. We bases on Deterministic Finite Automata (DFA) and propose some modifications to reduce redundant logic. The proposed design, with better memory utilization, is capable of dynamic update and compatible to stateful NIDS. The analysis of memory efficiency and the hardware implementation of proposed design are also provided in this paper. We experiment our approach on contemporary NIDS pattern sets and build a prototype to test on real network environment. The results show that our design could save up to 90% hardware resources compare to traditional approach. The matching engine is compatible to gigabit network and could achieve 2.7–3.2x speed up to software-based matching engine. [ABSTRACT FROM PUBLISHER]