Patients with acquired cystic kidney disease (ACKD) are at an increased risk of renal neoplasms. Frequent tumors are adenomas and renal cell carcinomas. However, renal oncocytomas may occur in ...patients with ACKD. Little is known about oncocytomas of the native kidney following renal transplantation. By means of B scan ultrasonography, a solid and echo-inhomogeneous renal mass was incidentically observed in the right native kidney of a 28-year-old female patient with ACKD 4 years following renal transplantation. A nephrectomy was performed. The histological examination revealed a renal oncocytoma. The increased prevalence of neoplasms in the case of ACKD and following renal transplantation requires careful monitoring of the patients concerned. In very rare cases a renal oncocytoma may develop in the native kidney after renal transplantation.
The structure of the 5′ domain of yeast 18S rRNA has been probed by dimethyl sulfate (DMS), either in “native” deproteinized molecules or in the 40S ribosomal subunits. DMS-reacted RNA has been used ...as a template for reverse transcription and a large number of reactive sites, corresponding to all types of bases have been mapped by a primer extension procedure, taking advantage of blocks in cDNA elongation immediately upstream from bases methy-Lated at atom positions involved in the base-pair recognition of the template. Since the same atom positions are protected from DMS in base-paired nucleotides, the secondary structure status of each nucleotide can be directly assessed in this procedure, thus allowing to evaluate the potential contribution of proteins in modulating subunit rRNA conformation. While the DMS probing of deproteinized rRNA confirms a number of helical stems predicted by phylogenetic comparisons, it is remarkable that a few additional base-pairings, while proven by the comparative analysis, appear to require the presence of the bound ribosomal subunit proteins to be stabilized.
This paper describes a nuclear binding assay (NB assay) which measures not only the presence of a steroid receptor in a tissue, but also the quantity of that receptor which is biologically active or ...functional, i.e. able to bind to nuclear acceptor sites. The assay involves the isolation viable cells from tissues and their incubation with an excess of radiolabeled steroid to encourage the activation and nuclear binding of all cellular receptors. The nuclei are isolated under conditions that remove unactivated (unbound) steroid-receptor complexes. This NB assay demonstrates, in both animal and human steroid target tissues, a saturable, tissue- and steroid-specific, and temperature- and time-dependent nuclear binding of radiolabeled steroids. These properties support a receptor-dependent nuclear binding of steroids. This assay is reproducible and requires relatively small amounts of tissue. The patterns of nuclear binding of the progesterone receptor, achieved with the assay in the avian oviduct model system, are shown to correlate with the nuclear binding of progesterone in vivo, the ability of the steroid to alter transcription, and the expression of a specific gene product, the protein avidin. The assay has been used to identify the existence of nonfunctional steroid receptors in endometrial and breast carcinomas. Therefore, this NB assay combined with the standard charcoal/hydroxylapatite methods of quantitating total cellular receptors should provide a means of assessing changes in the regulation of the biological activity of steroid receptors. Further, the assay should be useful to assess the ability of steroid analogs to properly activate their respective receptors for subsequent nuclear binding.
An analysis of the chiral-induced equilibrium shift of racemic D{sub 3} tris-terdendate complexes of lanthanides with 2,6-pyridinedicarboxylate is presented in terms of the associated/dissociated ...models of Schipper. Results are presented which indicate that the so-called Pfeiffer effect in these lanthanide complexes is best described by the dissociated model, as was determined for similar labile transition-metal complexes. The nature of the chiral discriminatory interaction is shown to be largely electrostatic by measurements in mixed solvents of varying dielectric constant.
Inhibin, a gonadal glycoprotein which suppresses pituitary gonadotrophin secretion, preferentially follicle stimulating hormone, has been extensively characterized. It consists of two covalently ...bound subunits, the alpha- and beta-subunits, encoded by separate genes. In this study, the expression of messenger ribonucleic acid (mRNA) for the inhibin alpha-subunit was studied by Northern blot analysis in granulosa cells of women undergoing in-vitro fertilization/embryo transfer (IVF/ET). Three patient groups were studied: women who failed to become pregnant (n = 11), women who became pregnant but experienced early spontaneous abortion (n = 3) and women who conceived normal ongoing pregnancies (n = 4). Granulosa cells were obtained at the time of follicle aspiration. Levels of alpha-subunit mRNA were 40% lower in patients establishing normal pregnancies than in those who failed to become pregnant or who spontaneously aborted. Thus, a relative diminution of immediately preovulatory levels of mRNA for inhibin alpha-subunit is a marker of success in clinical IVF/ET cycles. This marker of IVF/ET success can be related to previously established markers of success (increased follicular fluid oestradiol and decreased follicular fluid cyclic adenosine monophosphate) by known physiological mechanisms.
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