Carotenoid Nostoxanthin Production by Sphingomonas sp. SG73 Isolated from Deep Sea Sediment.

Carotenoids are used commercially for dietary supplements, cosmetics, and pharmaceuticals because of their antioxidant activity. In this study, colored microorganisms were isolated from deep sea sediment that had been collected from Suruga Bay, Shizuoka, Japan. One strain was found to be a pure yellow carotenoid producer, and the strain was identified as Sphingomonas sp. (Proteobacteria) by 16S rRNA gene sequence analysis; members of this genus are commonly isolated from air, the human body, and marine environments. The carotenoid was identified as nostoxanthin ((2,3,2',3')-ß,ß-carotene-2,3,2',3'-tetrol) by mass spectrometry (MS), MS/MS, and ultraviolet-visible absorption spectroscopy (UV-Vis). Nostoxanthin is a poly-hydroxy yellow carotenoid isolated from some photosynthetic bacteria, including some species of Cyanobacteria. The strain Sphingomonas sp. SG73 produced highly pure nostoxanthin of approximately 97% (area%) of the total carotenoid production, and the strain was halophilic and tolerant to 1.5-fold higher salt concentration as compared with seawater. When grown in 1.8% artificial sea salt, nostoxanthin production increased by 2.5-fold as compared with production without artificial sea salt. These results indicate that Sphingomonas sp. SG73 is an efficient producer of nostoxanthin, and the strain is ideal for carotenoid production using marine water because of its compatibility with sea salt.

An economic evaluation of Japanese telemedicine, focusing on teleradiology and telepathology.

We collected information by postal survey from 622 medical institutions reported to be using telemedicine in Japan. The questionnaire asked about willingness to pay (WTP) for telemedicine and willingness to undertake (WTU) it. The Kernel Estimation Method was used to obtain WTP for teleradiology (4379 yen), telepathology (9526 yen), teleconferencing (2084 yen) and teleconsultation (633 yen). The estimated WTU were teleradiology (3875 yen), telepathology (17,918 yen), teleconferencing (3230 yen) and teleconsultation (3643 yen). These values are larger than the current charges that customers actually pay or providers receive. Multiplying these values by the number of medical institutions that had implemented telemedicine allows the total annual benefits of telemedicine to be estimated, e.g. for teleradiology, the annual benefit in terms of WTP and WTU (millions of yen per year) were 140.20 and 1101.75, respectively. Based on the results of the survey, specific policy measures to promote telemedicine further include improvement of quality and reimbursement.

On the evaluation of economic benefits of Japanese telemedicine and factors for its promotion.

This paper attempts to estimate economic values of telemedicine and to extract factors that promote telemedicine through the use of survey data. This is the first analysis aimed at evaluating telemedicine in Japan. We utilized the Contingent Valuation Method and estimated demand functions of telemedicine. Because the number of institutions replying with willingness to pay (WTP) and willingness to undertake (WTU) is relatively small, the Kernel Estimation Method was applied. After estimating WTP and WTU, by multiplying the number of medical institutions currently implementing telemedicine, the whole value in Japan was obtained. By using the Tobit Model, factors that influence WTP and WTU were extracted. Estimated WTP was 35.23 dollars for teleradiology and 162.89 dollars for telepathology. WTU estimated was 39.81 dollars for teleradiology and 86.59 dollars for telepathology. Estimated economic benefits in Japan for 1 year were 1.27 million dollars for WTP of teleradiology and 278,600 dollars for telepathology. WTU is 10 million dollars for teleradiology and 393,400 dollars for telepathology. Medical institutions with the following characteristics tend to reply larger WTP: (1) university hospitals, (2) internal medicine, (3) radiology, and (4) use of video conference systems. Regarding WTU, the following characteristics influence WTU: (1) use of a personal computer, (2) use of telepathology equipment, (3) high satisfaction with the quality of telemedicine, and (4) experience base of telemedicine. Based on the nationwide survey on telemedicine, the total value of telemedicine in Japan was estimated. In addition to the evaluation, quantitative aspects of implementation of telemedicine, such as factors to promote telemedicine, are analyzed. These can provide useful information for further implementation of telemedicine not only in Japan but in other countries as well.