Production and Storage of Virus Simulants

We have examined isolation and identification protocols for three virus simulant candidates to biological warfare agents. MS2 phage, a simulant for yellow fever virus and Hantaan virus, was propagated using as a host an E. coli strain with F pilus. MS2 phage genome was examined by reverse transcription and polymerase chain reaction (RT-PCR). Coat protein of the phage preparation was examined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometric analysis. Cydia pomonella granulosis virus (CpGV) is a virus simulant candidate to smallpox virus. CpGV was isolated from a commercialized CpGV pellet. In this study, we developed new isolation and identification protocols for CpGV. One disadvantage of using CpGV is that it is not easy to determine viability of the virus. Here, we have included T4 phage as an alternative. We established a high titer production protocol and developed an easy genome identification protocol that does not require purified phage DNA. Stability of these virus preparations was also examined under various storage conditions. When the virus preparations were not subjected to freeze drying, MS2 phage was most stable when it was stored in liquid nitrogen but unstable at 4℃. In contrast, T4 phage was most stable when it was stored at 4℃. CpGV was stable at −20℃ but not at 4℃. Stability during or after freeze drying was also investigated. The result showed that 70~80% MS2 survived the freeze drying process. In contrast, only about 15% of T4 phage survived during the freeze drying. CpGV was found to be degraded during freeze drying.

Recipient Vessel Selection in Immediate Breast Reconstruction with Free Abdominal Tissue Transfer after Nipple-Sparing Mastectomy

BACKGROUND: Nipple-sparing mastectomy (NSM) is gaining popularity due to its superior aesthetic results. When reconstructing the breast with free abdominal tissue transfer, we must readdress the recipient vessel, because NSM can cause difficulty in access to the chest vessel. METHODS: Between June 2006 and March 2011, a total of 92 women underwent NSM with free abdominal tissue transfer. A lateral oblique incision was used for the nipple-sparing mastectomy. For recipient vessels, the internal mammary vessels were chosen if the mastectomy flap did not block access to the vessels. If it did, the thoracodorsal vessels were used. Age, degree of breast ptosis, weight of the mastectomy specimen, and related complications of the internal mammary vessel group and the thoracodorsal vessel group were compared. RESULTS: Thoracodorsal vessels were used as recipient vessels in 59 cases, and internal mammary vessels in 33 cases including 4 cases with perforators of the internal mammary vessels. Breast reconstruction was successful in all cases except one case involving a total flap failure, which was replaced by a silicone gel implant. The internal mammary group and the thoracodorsal group were similar in terms of age, height, breast weight, and degree of ptosis. The flap related complications such as flap loss and take-back operation rates were not significantly different between the two groups. The rate of nipple necrosis was higher in the internal mammary group. CONCLUSIONS: The thoracodorsal vessels could produce comparable outcomes in breast reconstruction after nipple-sparing mastectomies. If access to internal mammary vessels is difficult, the thoracodorsal vessel can be a better choice.