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A case of bilateral adrenal myelolipoma in association with congenital adrenal hyperplasia caused by 21-hydroxylase deficiency is presented. The clinical, radiologic, and endocrinologic features of this case are correlated with a review of the literature.

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Here we investigate the role of the Raf-1 kinase in transformation by the v-abl oncogene. Raf-1 can activate a transforming signalling cascade comprising the consecutive activation of Mek and extracellular-signal-regulated kinases (Erks). In v-abl-transformed cells the endogenous Raf-1 protein was phosphorylated on tyrosine and displayed high constitutive kinase activity. The activities of the Erks were constitutively elevated in both v-raf- and v-abl-transformed cells. In both cell types the activities of Raf-1 and v-raf were almost completely suppressed after activation of the cyclic AMP-dependent kinase (protein kinase A [PKA]), whereas the v-abl kinase was not affected. Raf inhibition substantially diminished the activities of Erks in v-raf-transformed cells but not in v-abl-transformed cells, indicating that v-abl can activate Erks by a Raf-1-independent pathway. PKA activation induced apoptosis in v-abl-transformed cells while reverting v-raf transformation without severe cytopathic effects. Overexpression of Raf-1 in v-abl-transformed cells partially protected the cells from apoptosis induced by PKA activation. In contrast to PKA activators, a Mek inhibitor did not induce apoptosis. The diverse biological responses correlated with the status of c-myc gene expression. v-abl-transformed cells featured high constitutive levels of expression of c-myc, which were not reduced following PKA activation. Myc activation has been previously shown to be essential for transformation by oncogenic Abl proteins. Using estrogen-regulated c-myc and temperature-sensitive Raf-1 mutants, we found that Raf-1 activation could protect cells from c-myc-induced apoptosis. In conclusion, these results suggest (i) that Raf-1 participates in v-abl transformation via an Erk-independent pathway by providing a survival signal which complements c-myc in transformation, and (ii) that cAMP agonists might become useful for the treatment of malignancies where abl oncogenes are involved, such as chronic myeloid leukemias.

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The purpose of this study was to review the authors' experiences with serial sodium Amytal (amobarbital) interviews and to compare these results with those found in the literature. A chart review of 21 patients with suspected conversion disorder evaluated by Amytal interview was conducted retrospectively. Presenting symptoms included movement disorders, focal neurologic deficits, chronic pain, "spells," and pseudoseizures. The serial Amytal interviews confirmed the presence of psychopathology noted on admission and revealed underlying psychosocial stressors. In 2 of 21 patients, agents other than Amytal were used after the first interview. This series confirms that the serial Amytal interview has utility in the clinical setting as a diagnostic and therapeutic tool.

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Reverse transcription of human immunodeficiency virus type 1 (HIV-1) is primed by tRNA(Lys3), which forms an 18 base pair RNA homoduplex with its 3' terminus and the primer binding site (PBS) of the viral genome. Using an in vitro system mimicking initiation of minus strand DNA synthesis, we analyzed the mechanism by which HIV-1 reverse transcriptase (RT)-associated ribonuclease H (RNase H) distinguishes between RNA/DNA and RNA/RNA (dsRNA). tRNA(Lys3) was hybridized to a PBS-containing RNA template and extended by addition of deoxynucleoside triphosphates (dNTPs). In the presence of all four dNTPs, initial cleavage of the RNA template occurred immediately downstream of the tRNA-DNA junction, reflecting RNase H specificity for RNA in a RNA/DNA hybrid. However, in the absence of DNA synthesis, or limiting this by chain termination, the PBS was cleaved at a constant distance of 18 nucleotides upstream of the nascent primer 3' terminus. The position of cleavage remained in register with the position of DNA synthesis arrest, indicating that hydrolysis of homoduplex RNA is spatialy co-ordinated with DNA synthesis. Kinetic studies comparing cleavage rates of an analogous DNA primer/PBS heteroduplex and the tRNA(Lys3)/PBS homoduplex showed that while the former is cleaved as rapidly as RT polymerizes, the latter proceeds 30-fold slower. Although the RNase H domain hydrolyzes dsRNA when RT is artificially arrested, specificity for RNA/DNA hybrids is maintained when DNA is actively synthesized, since residency of the RNase H domain at a single base position is not long enough to allow significant cleavage on dsRNA.

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