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Robert C Johnson

Publications and source records attributed to Robert C Johnson.

4 recordsLinked to original sources
PubMed2006

Increased gene copy number of the transcription factor E2F1 in malignant melanoma.

Translocations and unique chromosome break points in melanoma will aid in the identification of the genes that are important in the neoplastic process. We have previously shown a unique translocation in malignant melanoma cells der(12)t(12;20). The transcription factor E2F1 maps to 20q11. Increased expression of E2F has been associated with the autonomous growth of melanoma cells, however, the molecular basis has not yet been elucidated. To this end, we investigated E2F1 gene copy number and structure in human melanoma cell lines and metastatic melanoma cases. Fluorescent in situ hybridization (FISH) analysis using a specific E2F1 probe indicated increased E2F1 gene copies in melanoma cell lines compared to normal melanocytes. We also observed increased copies of the E2F1 gene in lymph node metastases of melanoma. In addition, Western blot analysis demonstrated increased E2F1 protein levels in 8 out of 9 melanoma cell lines relative to normal melanocytes. Inhibition of E2F1 expression with RNAi also reduced melanoma cell growth. Our results suggest that the release of E2F activity by elevated E2F1 gene copy numbers may play a functional role in melanoma growth.

Blotting, Western↗
PubMed2006

Incidental mononuclear cell infiltrate in the uvea of cynomolgus monkeys.

Mononuclear cell infiltrate (MCI) in the uvea was observed in naïve, untreated (control group) cynomolgus monkeys in approximately 25% of drug safety evaluation studies. The total incidence of MCI in the choroid and the ciliary body was 29% of 342 males and 25% of 306 female monkeys. In the studies in which MCI was present in the ciliary body or choroid, the incidence was as high as 75%. There were no other ocular histopathologic findings in these monkeys. All monkeys were clinically healthy and the eyes were not remarkable when examined ophthalmoscopically.

Animals↗
PubMed2006

Suicidal and homicidal soldiers in deployment environments.

Suicidal and homicidal soldiers present one of the most frequent and challenging scenarios for deployed mental health providers. A chart review of 425 deployed soldiers seen for mental health reasons found that 127 (nearly 30%) had considered killing themselves and 67 (nearly 16%) had considered killing someone else (not the enemy) within the past month. Of these, 75 cases were considered severe enough to require immediate intervention. Interventions included unit watch, comprehensive treatment, and medical evacuation. Of the 75 dangerous soldiers, 5 were evacuated out of theater. The rest were returned to duty. Evacuation to a hospital in the rear is often the quickest and most risk-free option but is seldom the best choice for maintaining the fighting force. This article presents several case examples and describes methods for dealing with suicidal and homicidal soldiers during deployment.

Adult↗