The toxicity of Asarum heterotropoides root steam distillate compounds to third instar larvae of Culex pipiens pallens, Aedes aegypti, and Ochlerotatus togoi (formerly Aedes togoi) was examined using a direct contact mortality bioassay. Results were compared with those following the treatment with fenthion and temephos. A. heterotropoides root steam distillate exhibited good larvicidal activity (21.07-27.64 ppm), based on LC50 values. Potent activity was produced by safrole (LC50, 8.22-16.10 ppm), terpinolene (11.85-15.32 ppm), -terpinene (12.64-17.11 ppm), (–)-β-pinene (12.87-18.03 ppm), (+)-limonene (13.26-24.47 ppm), 3-carene (13.83-19.19 ppm), and α-phellandrene (13.84-23.08 ppm), although the larvicidal activity of these compounds was less toxic than either fenthion (LC50, 0.023-0.029) or temephos (0.016-0.020). A. heterotropoides root steam distillate and its constituents described merit further study as potential mosquito larvicides for protection from humans and domestic animals from vector-borne diseases and nuisance caused by mosquitoes.

The repellency to female Stomoxys calcitrans (L.) of 21 essential oils alone or in combination with Calophyllum inophyllum nut oil (tamanu oil) was examined using a skin bioassay. Results were compared with those following treatment with the commonly used repellent DEET (N,N-diethyl-3-methylbenzamide). As judged by the protection time (PT) to first bite at 0.5 mg cm-2, patchouli (3.67 h) was the most effective essential oil, followed by clove bud, lovage root, clove leaf and thyme white essential oils (3.50-2.12 h). Thyme red, oregano and geranium essential oils exhibited moderate protection time (PT, 1.24-1.11 h). At 0.25 mg cm-2, effective protection time of clove bud, clove leaf and lovage root essential oils was about 1 h. The protection times of DEET were 4.47 and 2.17h at 0.5 and 0.25 mg cm-2 respectively. The remarkable increase in the protection time were produced by binary mixtures of five essential oils (clove bud, clove leaf, thyme white, patchouli and savory) and tamanu oil (0.25:2.0 mg cm-2) compared with those of either the constituted essential oil, tamanu oil or DEET alone, indicating the involvement in synergy. These essential oils, tamanu oil and binary mixtures did not cause any adverse effects on the human volunteers at 0.5 mg cm-2 except savory oil. Thus binary mixtures of essential oils and tamanu oil described merit further study as potential insect repellents for protection from humans and domestic animals from biting and nuisance caused by S. calcitrans.

In view of the recently increased interest in developing plant-origin insecticides are an alternative to chemical insecticides. This study was undertaken to assess the larvicidal potential of the two (H52C1 and H5C) compounds from Asarum sieboldii Miq. against dengue vector Aedes aegypti. Among the two compounds, compound I (H52C1) was most active than the compound II (H5C) against third instar larvae of Ae. aegypti. The LC50 value of the compound I was 2.03 (95% CL, 1.51-2.76) and the compound II was 10.66 (95% CL, 9.23-12.42). These findings would be useful in promoting research aiming at the development of new agents for mosquito larval control based on bioactive chemical compounds from plant origin.

The nematicidal activity of Kaempferia galanga rhizome-derived materials (methanol extract, steam distillate, and powder) toward M. incognita second-stage juveniles (J2) was examined using residual contact toxicity and pot bioassays. In residual contact toxicity bioassays with J2, the active principles of K. galanga rhizome were identified as the phenylpropanoids ethyl cinnamate (EC, 1) and ethyl-p-methoxycinnamate (EMC, 2) by spectroscopic analysis. EC exhibited 95% and 49% mortality at 0.06 and 0.04 mg/ml toward J2, respectively, whereas EMC showed 98% and 63% mortality at 0.1 and 0.08 mg/ml. In pot tests with J2, K. galanga rhizome methanol extract gave 92% and 82% mortality at 100 and 20 mg/50g soil, respectively. Steam distillate gave 88% and 68% mortality at 85 and 42.5 mg/50g soil, respectively, whereas rhizome powder provided 83% and 62% mortality at 400 and 200 mg/50g soil. K. galanga rhizome-derived materials, particularly EC and EMC, merit further study as potential root-knot nematode control agents or leads because of their great activity as a nematicide.

The repellent constituents of essential oils from Zanthoxylum armatum (Rutaceae) seed and Zanthoxylum piperitum fruit against female Stomoxys calcitrans were analyzed by gas chromatography and gas chromatography-mass spectrometry. The repellency of two Zanthoxylum essential oils and 11 oil compounds against female S. calcitrans was examined using a skin bioassay. Results were compared with those of the most widely used repellent DEET. Both Z. armatum seed and Z. piperitum fruit oils provided complete and good protection from fly bites for 30 min at 0.4 and 0.2 mg/cm2, respectively. At 0.05 mg/cm2, both oils gave ca 70 and 40% repellency at 30 and 60 min post-treatment, respectively, whereas DEET provided 83 and 73% protection. Of test compounds, cuminaldehyde at 0.05 mg/cm2 gave 92 and 69% repellency at 10 and 30 min post-treatment, respectively, whereas 1,8-cineole, and citronellal provided approx. 76% repellency at 10 min. The Zanthoxylum oils and their constituents, particularly cuminaldehyde, merit further study as potential insect repellents for the protection from humans and domestic animals from biting and nuisance caused by S. calcitrans.

The goal of medical education is to make a desirable physician who is needed and wanted from community. The images of this ideal physician has changed over the years. We analysed the questionnaires about a good doctor which were answered by 472 students of one university except for medical, dental, nursing and pharmaceutical students. The excellent physician was regarded as a competent doctor 251 (53.2%), a doctor who is good at explanation 154 (32.6%), and a kind doctor 65 (13.8%) and etc. The mean reliability score for physician was 3.4 and for medical services 3.3, by 5-point Likert scale. The survey subjects thought that medical education to make a good physician should include communication skills (27%), medical skills (26%), medical knowledge (19%), courtesy (11%) & etc.