Nonfluoroscopic guidance for catheter placement into the coronary sinus under direct vision using a balloon-tipped cardioscope

The right atrial posterior septum, including the coronary sinus (CS) ostium, is an important landmark in radiofrequency catheter ablation therapy for supraventricular tachycardia or atrial flutter. The anatomical findings around the CS ostium would be useful to determine a target site or line during catheter ablation. The aim of the study was to test the ability of the imaging catheter to identify structures in the posterior septal area of the right atrium and to evaluate the feasibility of guidance for catheter placement in the CS using a cardioscope that we recently developed. In 12 anesthetized dogs, the cardioscope, consisting of a deflectable 7 Fr fiberoptic endoscope with an inflatable and transparent balloon, was introduced into the right atrium via the femoral vein. The cardioscope was manipulated to observe the right atrial posterior septum. A deflectable electrode catheter was inserted via the jugular vein and positioned in the CS under cardioscopic guidance. In 10 of 12 dogs, the right atrial posterior septum, including the CS ostium, and the tendon of Todaro could be anatomically identified by cardioscopy. It was possible to position an electrode catheter in the CS in all 10 dogs under direct vision without fluoroscopy. But the CS ostium could not be detected in the remaining two dogs, although the cardioscope was placed at as many sites as possible. No complication occurred. The balloon-tipped cardioscope appears to be useful in observing the right atrialposterior septum and in guiding an electrode catheter into the CS.     

Isolation and characterization of high-osmolarity-sensitive mutants of fission yeast

For the fission yeast Schizosaccharomyces pombe, adaptation to high-osmolarity medium is mediated by a mitogen-activated protein (MAP) kinase cascade, involving the Wis1 MAP kinase kinase and the Sty1 MAP kinase. The MAP kinase pathway transduces an osmotic signal and accordingly regulates the expression of the downstream target gene (gpd1(+)) that encodes NADH-dependent glycerol-3-phosphate dehydrogenase, in order to adaptively accumulate glycerol inside the cells as an osmoprotectant. We previously characterized a set of high-osmolarity-sensitive S. pombe mutants, including wis1, sty1, and gpd1. In this study, we attempted to further isolate novel osmolarity-sensitive mutants. For some of the mutants isolated, profiles of glycerol production in response to the osmolarity of the growth medium were indistinguishable from that of the wild-type cells, suggesting that they are novel types. They were classified into three distinct types genetically and, thus, were designated hos1, hos2, and hos3 (high osmolarity sensitive) mutants. One of them, the hos1 mutant, was characterized in detail. The hos1 mutant was demonstrated to have a mutational lesion in the known ryh1(+) gene, which encodes a small GTP-binding protein. Disruption of the ryh1(+) gene results not only in osmosensitivity but also in temperature sensitivity for growth. It was also found that the delta ryh1 mutant is severely sterile. These results are discussed with special reference to the osmoadaptation of S. pombe.     

Increase in the expression of biglycan mRNA expression Co-localized closely with that of type I collagen mRNA in the infarct zone after experimentally-induced myocardial infarction in rats

Biglycan, a small dermatan sulphate proteoglycan, has been postulated to interact with other components of the extracellular matrix (ECM), specifically collagens. We hypothesized that biglycan messenger ribonucleic acid (mRNA) is increased in the myocardial infarct zone. Biglycan mRNA expression after acute myocardial infarction (AMI) in rats was determined with the use of Northern blotting and in situ hybridization, and its expression pattern was compared to that of type I collagen mRNA [alpha1(I) collagen]. The left coronary artery was ligated in male Sprague-Dawley rats, and the hearts were excised on days 2 and 7. The Northern blot analysis demonstrated that expression of biglycan mRNA in the infarct on days 2 and 7 were 4.0- and 6.8-fold higher, respectively, compared to the sham-operated hearts. The in situ hybridization revealed intense signals for both biglycan and alpha1(I) collagen mRNA on day 2 in the spindle-shaped mesenchymal cells located between the surviving myocytes in the infarct peripheral zone. On day 7, biglycan mRNA signals were observed in the interior of the infarct around the infarct granulation tissue, a distribution that was essentially the same as that of alpha1(I) collagen. These results demonstrated that the increases in the infarct biglycan mRNA expression produced by mesenchymal cells (presumably myofibroblasts and fibroblasts) was closely co-localized with that of type I collagen mRNA, indicating that biglycan contributes to the infarct healing processes.     

Changes in serum levels of sialoglycoproteins in mice exposed to UV-B radiation

In the acute phase reaction, hepatocytes in the liver are activated and increase the plasma levels of acute phase reactants. Our previous study has shown that plasma sialic acid, an acute phase reactant, was increased following exposure of mice to UV-B radiation. Plasma sialic acid is derived from many plasma components. To clarify the type of plasma sialic acid that is increased by exposure to UV-B radiation, we performed two-dimensional electrophoresis and staining for sialic acid. Consequently, the increases in haptoglobin and hemopexin were marked and 90% or more of the increased sialic acid was derived from these two glycoproteins after exposure to UV radiation. The increase in alpha1-acid glycoprotein levels was slight and did not contribute to the total increase in plasma sialic acid after exposure to UV radiation. Plasma levels of several proteins including antichymotrypsin (ACT), were reduced following exposure to UV radiation. The discrepancy between our results and published ones regarding ACT levels are discussed in terms of the type of cytokine.     

Pelvic reconstruction with a free fillet lower leg flap

Orthostatic tremor (OT) is a rare movement disorder that consists of involuntary shaking of the legs and trunk present only on standing. Although the origin and the mechanism of this condition are not well understood, the neurophysiologic abnormalities and PET studies suggest a central origin. We describe the clinical and radiologic features of two patients with symptomatic OT and associated pontine lesions, and conclude that OT may arise from dysfunction of the cerebellum or related pontine structures.     

Discordant splenic uptake of Tc-99m colloid and Tc-99m denatured RBC in candidiasis-endocrinopathy syndrome

The aim of this study was to estimate the incidence of melanoma in the Paris region in 1994 and analyse the main clinical and histological characteristics of these lesions. It took the form of a prospective inquiry, mailed to public and private pathology laboratories, to count as accurately as possible the number of new cases diagnosed by pathologists in the region during the 1994 calendar year. In all, 1089 newly diagnosed Clark level I to V melanomas (excluding precancerous melanosis of Dubreuilh) were studied. Parameters recorded included age, sex, Clark level and Breslow's thickness. The incidence per 100,000 inhabitants was 9.93 for melanoma and 8.62 for invasive melanoma. The female to male ratio was 1.6. Clark level I or thin (< 0.75 mm) melanomas represented 64.8% of the lesions. At the time of diagnosis, the females were significantly younger than the males (P = 0.004). Breslow's thickness increased with age and was significantly lower in women (P = 0.00005), especially those between 40 and 49 years old. The incidence of melanoma in the Paris region in 1994 was close to that observed during the preceding 5 years in England, Scotland and the French department of Haut-Rhin. It was 2.32 times higher for males and 1.69 times higher for females than the rates estimated for France for the period 1978-1982.