Case Report: Gastroepiploic Artery Pseudoaneurysm as a Cause of Abdominal Apoplexy. Role of CT Scanning

Abdominal apoplexy can be a difficult condition to diagnose prior to surgery. A case is reported where intra-abdominal bleeding resulting from a gastroepiploic artery pseudoaneurysm was diagnosed prior to operative intervention with CT Scanning including dynamic studies. The authors believe that this method of imaging does have a place in the diagnosis of suspected intra-abdominal bleeding, and the condition and the place of CT Scanning in this instance are briefly reviewed.     

Entrainment of Typical AV Nodal Reentrant Tachycardia Using Para-Hisian Pacing:

INTRODUCTION: Despite the ability to cure atrioventricular nodal reentrant tachycardia (AVNRT) by radiofrequency catheter ablation with a high success rate, the exact localization of the tachycardia circuit is still not well established. The presence of AV nodal tissue between the typical AVNRT circuit and the His bundle, constituting a lower common pathway (LCP), remains controversial. METHODS AND RESULTS: Entrainment of AVNRT during para-Hisian stimulation allows accurate measurement of the His- to- atrial (HA) interval which is part of the same circuit as that of the tachycardia. With an LCP, during tachycardia, there is simultaneous conduction from the low turnaround of the circuit to the atrium (via the fast pathway) and to the His bundle (via the LCP). However, during entrainment by para-Hisian pacing, the impulse has to retrogradely depolarize sequentially the LCP and the fast pathway. Therefore, in the presence of an LCP, the HA interval duration during tachycardia (HAt) should be shorter than that of during entrainment by para-Hisian stimulation (HAe). We considered an LCP present when Hae - HAt was > or = 10 msec. Entrainment of typical AVNRT with para-Hisian stimulation was performed in 23 consecutive patients (21 females) with a mean age of 45+/-17 years. LCP was considered to be present in 18 of 23 patients (78%). In addition, transient His-bundle dissociation from the ongoing tachycardia occurred in seven patients (30%). CONCLUSION: These results support the presence of a LCP during typical AVNRT.     

CD44 IS AN INDEPENDENT PROGNOSTIC FACTOR IN CONVENTIONAL RENAL CELL CARCINOMAS

PURPOSE: CD44 is a transmembrane glycoprotein involved in cell-cell and cell-matrix interactions. De novo expression of CD44 and its variant isoforms has been associated with aggressive behavior in various tumors. Since few data are available concerning the role of CD44 in the biological behavior of locally confined renal tumors, we analyzed the expression of CD44 in a large set of conventional renal cell carcinomas to determine its prognostic value in association with other clinicopathologic variables. MATERIALS AND METHODS: Ninety-one patients with locally confined conventional renal cell carcinomas were studied. CD44 standard form (CD44H) and v6 isoform expressions were semiquantitatively evaluated on paraffin-embedded tumor tissue by immunohistochemistry. The prognostic value of the usual clinicopathological variables and CD44 expression was tested using Kaplan-Meier plots by the log rank test and Cox multiple hazard regression analysis. RESULTS: No immunostaining was observed in normal renal tissue. Thirty-two of the 66 conventional renal cell carcinomas (48%) showed CD44H membranous staining of the tumor cells. Only 2 cancers displayed CD44v6 immunostaining. Among the different clinicopathological variables analyzed, tumor stage (p = 0.001), nuclear grade (p = 0.01), size (p = 0.02), vascular (p = 0.05) and perirenal adipose tissue invasion (p = 0.005), and CD44H expression (p = 0.01) were found to be significant prognostic parameters for survival using univariate analysis. Moreover, multivariate analysis indicated stage, nuclear grade and CD44 expression as independent prognostic factors both for overall and disease-free survival. CONCLUSION: CD44 can be considered as a useful prognostic parameter in conventional renal cell carcinoma and may be used in evaluation of the outcome of these tumors.     

1H-NMR conformational study of a synthetic peptide derived from the consensus sequence of Annexins

The solution conformation of a synthetic 18 amino acid peptide derived from a consensus sequence of Annexins has been investigated by ¹HNMR. Full sequential assignment has been achieved. Conformational properties of the peptide were deduced from the analysis of J(NH–CH_α) coupling constants, amide proton exchange, 2D NOESY connectivities and computer modeling.     

Iloprost: Intracellular Ca2+-dependent Contractile Effect on Isolated Smooth Muscle Cells from Guinea-pig Ileum

Prostaglandin E₂ (PGE₂) and iloprost induced a concentration-dependent contraction of smooth muscle cells isolated from the circular layer of guinea-pig ileum. PGE₂- and iloprost-induced contractions were inhibited by the selective EP₁-receptor antagonist, SCI9220 (1-acetyl-2-(8-chloro-10, 11-dihydrodibenz (b,f) (1,4) oxazepine-10-carbonyl)-hydrazine), indicating the involvement of the EP₁ subtype of the PGE₂ receptor. When cells were incubated for 10 min in the presence of strontium (4 mm L^?1), an inhibitor of the release of Ca²⁺ from intracellular store, the contractile effect of PGE₂ and iloprost was inhibited. In contrast, incubation of cells in Ca²⁺-free medium, Ca²⁺-free medium plus EGTA, or in the presence of nifedipine, an organic Ca²⁺-channel blocker, did not alter the PGE₂- and iloprost-induced contraction. These observations suggest that the myogenic effect of PGE₂ and iloprost on intestinal smooth muscle is dependent on the release of intracellular calcium.     

Attention modulates auditory pattern memory as indexed by event-related brain potentials

The role of selective attention on auditory pattern processing was investigated using the mismatch negativity, an event-related brain potential component associated with sensory memory. Participants responded to changes in an alternating tone pattern in a designated ear while a similar auditory pattern was presented in the opposite ear. Participants were also presented with the same sequences while reading a book (no response required). In all conditions, changes in the pattern elicited a mismatch negativity (MMN) that peaked at 160–220 ms poststimulus. MMN amplitude varied with attention: the amplitude was higher in response to deviant stimuli presented in the attended ear than to the deviant stimuli presented in the unattended ear or during reading. The results show that selective attention modulates auditory pattern memory.     

Inhibition of Induced Lymphocyte Proliferation by Lipid and Protein Components of the Syncytiotrophoblast Plasma Membrane

PROBLEM : The aim of this work was to define the respective responsibilities of the lipid and protein components of syncytiotrophoblast plasma membranes on the inhibition of lymphocyte proliferation induced in vitro. METHOD : A fractionation method using octyl-β-D-glucopyranoside enabled lipoprotein, lipid, and protein fractions to be isolated from the membrane. RESULTS: The lipid fraction was shown nonspecifically to inhibit lymphocyte proliferation, to a lower extent compared with the native membrane. Alternatively, the protein fraction used as a proteoliposome contained the totality of the cytostatic effect of the native fraction. CONCLUSION : These results are discussed generally in the context of the immunoregulatory role of membrane lipids and proteins and in relation to the local properties of syncytiotrophoblast plasma membrane components in fetal graft tolerance.