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Infection with Helicobacter pylori is strongly associated with gastric cancer and gastric adenocarcinoma. WHO classified H. pylori as a group 1 carcinogen in 1994. Impatiens balsamina L. has been used as indigenous medicine in Asia for the treatment of rheumatism, fractures and fingernail inflammation. In this study, we isolated anti-H. pylori compounds from this plant and investigated their anti- and bactericidal activity. Compounds of 2-methoxy-1,4-naphthoquinone (MeONQ) and stigmasta-7,22-diene-3β-ol (spinasterol) were isolated from the pods and roots/stems/leaves of I. balsamina L., respectively. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) for MeONQ were in the ranges of 0.156–0.625 and 0.313–0.625 μg mL−1, respectively, and in the ranges of 20–80 μg mL−1 both of MICs and MBCs for spinasterol against antibiotic (clarithromycin, metronidazole and levofloxacin) resistant H. pylori. Notably, the activity of MeONQ was equivalent to that of amoxicillin (AMX). The bactericidal H. pylori action of MeONQ was dose-dependent. Furthermore, the activity of MeONQ was not influenced by the environmental pH values (4–8) and demonstrated good thermal (121°C for 15 min) stability. MeONQ abounds in the I. balsamina L. pod at the level of 4.39% (w/w db). In conclusion, MeONQ exhibits strong potential to be developed as a candidate agent for the eradication of H. pylori infection.

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Preparation of Lipid II analogues containing an enzymatically uncleavable 1-C-glycoside linkage between the disaccharide moiety and the pyrophosphate- or pyrophosphonate-lipid moiety is described. The synthesis of a common 1-C-vinyl disaccharide intermediate has been developed that allows easy preparation of both an elongated sugar-phosphate bond and a sugar-phosphonate moiety, which are coupled with the polyprenyl phosphate to give the desired molecules. Inhibition studies show how a subtle structural modification results in dramatically different potency toward bacterial transglycosylase (TGase), and the results identify Lipid II-C-O-PP (IC50 =25 μM) as a potential TGase inhibitor.

A computer-assisted music-learning system (CAMLS) has been developed to help the hearing impaired practice playing a musical melody. The music-learning performance is evaluated to test the usability of the system. This system can be a computer-supported learning tool for the hearing impaired to help them understand what pitch and tempo are, and then learn to play songs thereby increasing their interest in music classes and enhancing their learning performance. The results indicated that CAMLS could enhance hearing-impaired students' learning performance in a music course. A questionnaire survey also demonstrated that the computer-aided method did benefit hearing-impaired students in their music leaning. Actually, this system can also be applied to non-disabled students as a music-supportive tool to help their music learning.

Lipid II analogues bearing major modifications on the second sugar (GlcNAc) were synthesized and evaluated for their substrate activity toward TGases. Unexpectedly, N-deacetyled lipid II decreased its activity dramatically, and the C4-axial OH lipid II became an inhibitor (IC = 8 μM) with an approximately 14-fold increase in binding affinity toward TGase (25 vs. 27).