[Age-dependent changes in glucocorticoid receptors in rat liver following functional loading in in-vivo and in-vitro systems]

In aging the transformation, nuclei binding, and recycling of glucocorticoid receptor complexes (GRC) seem to be retarded or disturbed, as shown in the rat liver after stress and in an in vitro-system. Reasons of the retarded in vitro-transformation and DNA-binding could be changed properties of the receptor protein or of cytosolic modulators, in which the tested heat-stable factor f is not responsible for the aging changes. The observed aging differences, when studying the nuclei binding after Ca2+ addition, result in the question, to what extent phosphorylation/dephosphorylation processes play a role in transformation and nuclei binding of GRC.

[Kimura disease--2 case reports]

Two histologically confirmed cases of Kimura's disease are reported in the present article. Emphasis is placed on the clinical symptoms in conjunction with the histological picture. Recent studies in the literature are discussed with respect to differential diagnosis, etiology and therapy. In all ENT-tumours of unknown origin this relatively uncommon disease should also be considered.

Continuous arteriovenous haemodiafiltration in the critically ill: influence on major nutrient balances

The impact of continuous arteriovenous haemodiafiltration (CAVHD) on nitrogen, lipid and carbohydrate balance was studied in 9 parenterally fed critically ill patients with acute renal failure. The effects on carbohydrate delivery of varying dialysate glucose concentrations or flow rates were also investigated. The total daily nitrogen loss was a mean of 24.1 g (95% CI 20.9-27.3 g/24 h) with non-urea nitrogen losses of 7.6 g (95% CI 5.6-9.6 g/24 h). Glucose delivery was a mean 5.8 g/h with a dialysate glucose concentration of 1.5% and a flow rate of 1 l/h (95% CI 4.5-7.0 g/h). Carbohydrate delivery increased with increased dialysate glucose concentration (mean 11.4 g/h with 2.5% glucose: 95% CI 9.6-13.1 g/h; mean 14.9 g/h with a 4.25% concentration: 95% CI 10.9-19; and with increased dialysate flow rates (mean 9.6 g/h, 95% CI 6.8-12.4 g/h, using 2 l/h of 1.5% glucose). Only trace amounts of cholesterol and/or triglycerides were detected in occasional ultradiafiltrate samples. CAVHD has an important impact on nitrogen and carbohydrate balance, but not on lipid status. Knowledge of these interactions is crucial for the rational planning of nutritional strategies in the critically ill.

Rapid increase in inositol phosphate levels in norepinephrine-stimulated vascular smooth muscle

We examined the correlation between agonist-stimulated increases in inositol phosphates and force development in vascular smooth muscle. Segments of rat tail artery were preincubated with [3H]inositol and treated with norepinephrine (10(-5) M) for 3-10 s. Tissue levels of inositol monophosphate (IP), inositol bisphosphate (IP2), and inositol trisphosphate (IP3) were measured. IP and IP2 increased significantly after 3 s of norepinephrine treatment. IP3 increased significantly after 5 s of norepinephrine treatment. Analysis of tissue extracts by high-pressure liquid chromatography demonstrated that the only isomer of IP3 present in any tissue extract was the 1,4,5-isomer [Ins(1,4,5)P3]. Contractile response to norepinephrine stimulation showed that the increase in inositol phosphates coincides well with the time course of force development. This is the first report demonstrating such an early increase in Ins(1,4,5)P3 in agonist-stimulated vascular smooth muscle. These results are consistent with the hypothetical role of Ins(1,4,5)P3 as a mediator linking agonist-receptor activation to increased intracellular calcium and force development in norepinephrine-stimulated vascular smooth muscle.

An embryo-specific protein of barley (Hordeum vulgare)

An immunological approach has been used to identify embryo-specific products that can be used as molecular markers of embryogenesis. Immunoadsorption of antisera to remove antigens common to embryos, meristematic cells and callus, revealed one major embryo-specific antigen, a polypeptide of 17 kDa. The antigen appeared at mid-stages of zygotic embryo formation and remained at similar levels up to six days post-germination of the seedling. The polypeptide could not be detected by protein staining, suggesting it is a non-abundant product. Appearance of the antigen could be induced by culture of zygotic embryos in vitro on abscisic acid (1 microM) or mannitol (9% mass/vol.). Cross-reactive products of near-identical molecular mass were observed in embryos of wheat, rye and oats but not distantly related cereals, nor embryos from dicotyledonous species. The timing of the appearance of the antigen was different in embryos formed from microspores during anther culture in vitro. In the cultured material, the 17-kDa polypeptide preceded the appearance of morphologically distinct embryonic structure.

[A measuring procedure for experimental determination of tensile strength of catheters and flexible probes]

In order to obtain a more objective description of the properties usually subsumed under such terms as the "handling" of catheters, it is necessary to measure the significant parameter bending stiffness. A contact-free method of recording the oscillations of rod-shaped elements is presented. The stiffness EI can be calculated from the measured characteristic frequency. The logarithmic decrement can be derived from the damped natural oscillation and the damping properties of the catheter thus characterised. In addition, a consideration of imposed oscillations can be employed to calculate resonance frequency. A computer-driven measuring set-up employing a CCD line camera for the non-contact recording of oscillations of rodshaped elements, together with the software required is presented. The measuring principle and possible errors are discussed and a measurement described by way of an example.

Identification of a thioredoxin-related protein associated with plasma membranes

A low molecular weight membrane associated sulphydryl protein was detected on a wide range of nucleated cells when [14C]-iodoacetamide was used as a probe. This protein was extracted from THP-1 monocytes, purified to homogeneity and its isoelectric point, Mr and N-terminal amino acid sequence determined. These were shown to be almost identical to the corresponding values for both human thioredoxin and a Tac interleukin-2 receptor activator, indicating that the protein may be a member of this family and function as an essential growth factor.

A modified method for the detection of nucleolar organizer regions (AgNORs)

A modified method for the detection of argyrophilic nucleolar organizer regions (AgNORs) is described. By combination of the original silver staining with a Feulgen staining at the same specimen both the AgNORs and the nuclei of the cells under study are sufficiently contrasted, so that a partial automated counting and measurement of these structures can be done using a computerized microscope image analysis system.

Computer-assisted image analysis of nucleolar organizer regions (NORs): a pilot study of astrocytomas and glioblastomas

Computer-assisted image analysis was used to measure nucleolar organizer regions (NORs) of 22 astrocytomas and glioblastomas. Image analysis provides reproducible information about number and size of NORs together with further karyometric data, which can be compared and processed with other patient-related data. Our study exhibits a statistical relationship between number and size of NORs and malignancy of the measured gliomas.

[Unusual chordoma of the neck region simulating salivary gland pleomorphic adenoma]

We report a 34-year-old woman with a cervical chordoma consisting of an intraspinal and extraspinal portion. The extraspinal component of the tumor invaded the deeper structures of the left side of the neck, and was subjected to repeated partial removal. It was misinterpreted as pleomorphic adenoma of salivary gland origin, whereas the intraspinal portion was a neurilemmoma with unusual mucous degeneration.

Photoelastic stress comparison of warm (Endotec) versus cold lateral condensation techniques

Stress generated during gutta-percha obturation of root canals can create microcracks and ultimately lead to failure. A new thermosoftening device, the Endotec, which develops a warm lateral condensation technique, was tested against the traditional lateral condensation procedure. The results indicated that the warm lateral condensation technique created less stress during obturation than did cold lateral condensation.

Disulfide bridge formation between C1q and IgG in vitro

The globular heads of C1q are known to possess free-SH groups. Here we show that these groups, which are concealed in the native molecule, are exposed by interaction of C1q with dialysis membrane. During iodination, I+ and I2 oxidize these sulfhydryls to produce disulfide-linked C1q aggregates. Approximately 15% of C1q bound to immunoglobulin aggregates is resistant to high conductivity elution and reducing agent is required to release it. These data show that dialysis, adsorption to Ig and iodination of C1q result in structural and functional changes in the molecule, and suggest a mechanism by which these changes occur. Disulfide bridging between C1q and IgG in vitro suggests that this may be a normal physiological function of C1q for which the free cysteines of human, mouse and guinea pig C1q have been conserved.

[Cushing's syndrome in CRF-producing mediastinal carcinoid]

A 36-year-old patient developed marked pigmentation, marked myopathy and severe hypokalaemic alkalosis which at first pointed towards an ectopic ACTH syndrome. The dexamethasone test at a high dose indicated cortisol suppression. A mediastinal tumour was seen radiologically, but the sella was of normal size. Computed tomography provided indirect signs of a sellar space-occupying lesion which suggested an ectopic production of corticotropin-releasing factor (CRF) as cause of the Cushing's syndrome. CRF concentration in antecubital venous blood was markedly elevated to 280 ng/l. The mediastinal tumour was excised and proved to be a carcinoid histologically. Postoperatively the CRF concentration fell to 70 ng/l. An extract of the carcinoid contained 15.5 ng/g wet-weight of CRF and 254 ng/g wet-weight of beta-endorphin. The patient died 5 weeks postoperatively of sepsis with bilateral pneumonia. At autopsy the hypophysis was of normal size but showed nodular ACTH-cell hyperplasia. This was thus a case of Cushing's syndrome resulting from ectopic CRF production in a mediastinal carcinoid tumour.