Solution structure of the phosphorylated sites of ribosomal protein S6 by 1H NMR spectroscopy

An increase in the rate of protein synthesis is found to be accompanied by phosphorylation of the 40S ribosomal protein S6. Treatment of S6 by cyanogen bromide produced three fragments, and one of the fragments of S6, which is a C-terminal portion of S6 (M_r? 4000), contains all phosphorylation sites of S6. The C-terminal fragment of S6 contains seven serines. S6 kinase phosphorylates S6 specifically, i.e. five serines in the C-terminal of S6 are phosphorylated. The three-dimensional structure of S6 peptide was studied in 50% trifluoroethanol/50% H₂O solution by ¹H NMR with combined use of distance geometry and restrained molecular dynamics calculations. NMR results indicated that it takes an α-helix between Glu5 and Arg21 and a distorted helical structure for the following three residues, but no rigid structure was present from Ser25 through the C-terminus and for the N-terminal region (Lys1-Lys4). The specificity of the phosphorylation of the peptide is discussed from a structural aspect. © Munksgaard 1996.     

Recto-peritoneal fistula following transperineal prostate biopsy

A recto-peritoneal fistula is an extremely rare complication after prostate biopsy. We report herein on a peritonitis arising from a recto-peritoneal fistula 5 days after undergoing prostate biopsy. To our knowledge, this is the first case of recto-peritoneal fistula following transperineal needle biopsy of the prostate in the published literature.     

Solution structure of a human calcitonin analog elucidated by NMR and distance geometry calculations

Three-dimensional structure of a human calcitonin analog (abbreviated as hCTa) in which the amino acids of the wild type are replaced at positions 12, 16 and 19 by leucine residues and further at position 22 by a tyrosine residue was studied in TFE solution by ¹H-NMR and distance geometry calculations. This analog has a 15-20 times activity as compared with the wild type. The amino acid replacements resulted in formation of an amphiphilic α-helix in the region between the residues 4-20. The overall three-dimensional structure is similar to that of the wild type. The conformational feature of hCTa with a hydrophobic face composed with a Met and four Leu residues may be related to its higher hypocalcemic potency.     

ULTRASTRUCTURAL CHANGE OF THE GLOMERULAR BASEMENT MEMBRANE IN RATS WITHHEYMANN NEPHRITIS REVEALED BY ULTRAHIGH RESOLUTION SCANNING ELECTRON MICROSCOPY

To assess the relationship between the glomerular injury induced by immune complex deposition and proteinuria, ultrastructural changes of the glomerular basement membrane (GBM) were investigated in Heymann nephritis. Active Heymann nephritis was induced in rats by injecting them with tubular brush border antigen, known as Fx1A, emulsified in complete Freund's adjuvant (CFA). Measurement of urinary protein excretion and histological examinations were carried out for up to 15 weeks after immunization. Proteinuria developed in rats within 10 weeks of immunization and coincided with the development of subepithelial deposits with minimal spike-like basement membrane protrusion. Acellular glomeruli were prepared by detergent treatment and were subjected to tannic acid–osmium conductive staining prior to examination with an ultrahigh resolution scanning electron microscope (HSEM). HSEM of the acellular GBM prepared from control rats injected with CFA alone revealed a meshwork structure, with pores of about 9 nm in diameter. Proteinuric rats immunized with Fx1A showed a loosened meshwork structure, with pores of about 15 nm in the acellular GBM adjacent to the deposits. The newly formed GBM overlying the deposit consisted of a meshwork structure associated with unorganized thin fibrils. Ultrastructural changes were never seen in GBM devoid of deposits. These findings indicate that subepithelial deposits are closely involved in the development of proteinuria by injuring the size selectivity of the GBM.     

Heart Rate Turbulence as a Predictor of Cardiac Mortality and Arrhythmic Events in Patients with Dilated Cardiomyopathy: A Prospective Study

Background: Few studies have described the clinical usefulness of heart rate turbulence (HRT), an autonomic predictor of mortality, in stratifying patients with dilated cardiomyopathy (DCM) at risk of cardiac mortality and arrhythmic events. We prospectively assessed the utility of HRT for risk stratification in patients with ischemic or nonischemic DCM.
Methods: We enrolled 375 consecutive patients with DCM including ischemic (n = 241) and nonischemic causes (n = 134). HRT was measured using an algorithm based on routine 24-hour Holter electrocardiograms, assessing 2 parameters: turbulence onset (TO) and turbulence slope (TS). HRT was considered positive when both TO was ≥0% and TS was ≤ 2.5 ms/R-R interval. The primary endpoint was defined as cardiac mortality and the secondary endpoint as occurrence of hemodynamically stable sustained ventricular tachyarrhythmias.
Results: Of patients enrolled, 83 patients (22.1%) were not utilized for HRT assessment because there were too few ventricular premature beats, or for other reasons. Eighty-one of 292 patients (27.7%) were HRT-positive. During follow-up of 445 ± 216 days, 30 patients (10.3%) reached the primary endpoint and 17 patients, the secondary endpoint. The hazard ratio (HR) of patients with an HRT-positive outcome was 6.4 (95%CI, 3.0–14.1; P < 0.0001) for the primary endpoint and 5.1 (95%CI, 2.8–9.3; P < 0.0001) for combined endpoints. On subanalysis, HRT positivity was significantly associated in both the ischemic and nonischemic DCM patients with both the primary endpoint (HR = 4.9, P = 0.0006 and HR = 12.3, P = 0.002, respectively) and with combined endpoints.
Conclusions: HRT is a powerful risk stratification marker for cardiac mortality and arrhythmic events in patients with DCM whether ischemia is present or not.     

Interleukin-2 receptor positive T and B cells in children with acute severe asthmatic attack

Subpopulations of interleukin-2 receptor (IL-2R)-positive CD4 and CD8 T cells and IL-2R⁺ CD20 B cells in the peripheral blood lymphocytes as well as serum concentrations of soluble IL-2R (sIL2R) were measured in children aged 1–7 years who suffered acute severe asthmatic attack. Subpopulations of CD4⁺ IL-2R⁺ cells, CD8⁺ IL-2R⁺ cells and CD20⁺ IL-2R⁺ cells in the peripheral blood lymphocytes at acute severe asthmatic attack phase were significantly higher than those at non-asthmatic attack phase (P < 0.02, P < 0.03 and P < 0.02, respectively). Subpopulations of CD20⁺ IL-2R⁺ cells in the peripheral blood lymphocytes significantly decreased 5–10 days after acute severe asthmatic attack (at recovery phase, P < 0.02) and were significantly correlated with clinical severity of asthmatic attack (P < 0.05). These results indicated that activation of both T cells and B cells was important in the pathogenesis of acute asthmatic attack in young children.     

Coronary Venous Lead Implantation after an Evaluation by Virtual Histology Intravascular Ultrasound and Stenting of a Stenosis

We describe a patient who developed coronary vein (CV) stenosis shortly (<3 months) after an initial left ventricular (LV) lead implantation with significant fibrous tissue. The virtual histological intravascular ultrasound analysis was useful for characterizing the plaque component of the stenotic lesion and formulating the strategy. A summarized review of the CV angioplasty for LV lead implantations disclosed that CV stenosis was often found in patients who had a previous history of cardiac surgery or an LV lead implantation and that a stent implantation was required to deploy the LV lead in the targeted CV in some (9.3%) patients. (PACE 2013; 36:e59–e63)     

Growing cavernous haemangioma of the liver: 11-fold increase in volume in a decade

A 57 year old Japanese male was incidentally found to have a 7.5 cm diameter hepatic haemangioma. Eleven years later he was operated on because the haemangioma had grown into a 17 cm mass causing upper abdominal fullness. Volumetry on computerized tomograms disclosed that the haemangioma had grown from 123 cm3 to 1343 cm3 in volume. Quantitative documentation on growing hepatic haemangioma has been rare.     

Effect of addition of hyaluronic acid to highly concentrated insulin on absorption from the conjunctiva in conscious diabetic dogs

Abstract— Insulin absorption from the conjunctiva was investigated in five pancreatectomized diabetic mongrel dogs, with the nasolacrimal ducts occluded by micro plugs to prevent insulin absorption from nasolacrimal membrane. In the anaesthetized state, highly concentrated porcine insulin (1000 units mL^?1, pH7·4) was absorbed rapidly and significantly from the conjunctiva. Plasma immunoreactive insulin concentrations increased significantly up to 3 h after insulin administration to conjunctival membranes. Plasma glucose concentration decreased significantly compared with saline control experiments after insulin administration (10 units kg^?1) at 3 h (8·3 ± 0·1 vs 15·6 ± 0·6 mmol, P < 0·01). However, in the conscious state, there was no significant increase in the plasma insulin levels after topical insulin administration. To improve insulin absorption in the conscious state, we examined the effect of increasing viscosity of insulin preparation with hyaluronic acid. In anaesthetized experiments, there were no significant changes in the bioavailability of insulin after addition of hyaluronate (0·84 ± 0·11 vs 0·87 ± 0·05%). In the conscious state, with addition of hyaluronic acid, the area under the curve of plasma insulin concentration was significantly increased (1842 ± 383 vs 75 ± 24 m units min L^?1, P < 0·01). The bioavailability of insulin absorption was significantly increased after addition of hyaluronate (0·68 ± 0·14 vs 0·03 ± 0·01%, P < 0·01). From this study we could demonstrate that the conjunctiva is a potential route for insulin administration, and increased viscosity by the addition of hyaluronate was found effective in increasing the bioavailability of insulin absorption from conjunctival membrane in the conscious state.