Perspective on Bifurcation PCI

Coronary bifurcation lesion is a complex lesion with suboptimal angiographic and clinical results. There has been no satisfactory classification of the lesion that can guide selection of strategies and predict short- and long-term outcomes. The difference between left main (LM) bifurcation lesions and non-LM bifurcation is striking. So many stenting strategies have been proposed and tried in trials. They include the V, T, Y, one-stent, two-stent, crush, mini-crush, DK, and SKS techniques. However, because these techniques are time and labor intensive, dedicated bifurcated stents have been invented and trialed in humans. This review presents a historical perspective of interventions in bifurcated lesions, with the strengths and weaknesses of the major strategies and of the new dedicated stents.     

Facilitative effects of EGb 761 on olfactory recognition in young and aged rats

The aim of the present study was to evaluate the effects of chronic and acute treatment by the Gingko biloba extract, EGb 761 (IPSEN, France) on olfactory short-term memory in rats, using a spontaneous recognition procedure. The effects of a daily EGb 761 treatment (30 or 60 mg/kg) over a period of 30 days (Experiment 1) were evaluated in young male rats. Those of a single injection of EGb 761 were assessed either in young male rats at 60 or 120 mg/kg (Experiment 2) or in aged female rats at 60 mg/kg (Experiment 3). Results showed that, at the highest dose (60 mg/kg), chronic EGb 761 treatment enhanced the recognition performances, allowing recognition at delays at which control animals did not show any recognition. Acute treatment enhanced recognition at both doses tested. The results of the third experiment showed that EGb 761 had an overall enhancement effect on the performances of aged rats. In summary, our results provide evidence for a short-term memory enhancement effect of EGb 761 in both young and aged rats.     

Angiographic Anatomy of the Coronary Sinus and Its Tributaries

Permanent left ventricular pacing has been shown to imporve the hemodynamic and clinical status of patients with severe heart failure. To pace the left ventricle, the electrode is implanted in tributaries of the coronary sinus (CS). However, the anatomy of cardiac veins with this purpose in mind has not been described in detail. Methods: One hundred consecutive patients admitted for coronary angiography had a simultaneous coronary venography performed after the injection of 8 to 10 mL of contrast material into the left coronary artery. Cardiac veins were analyzed in antero-posterior, left anterior oblique 60±, and right anterior oblique 30± views by three different observers. The number, dimension, angulation, and position of the coronary sinus and of its tributaries were studied. Results: Two veins are consistently present: the middle cardiac vein (mean diameter 2.62 ± 1.26 mm) and the great cardiac vein (mean diameter 3.55 ± 1.24 mm). The left posterior vein(s) (LPV) (mean diameter 2.25 ± 1.2 mm) is (are) variable in number (ranging from 0 to 3), size, and angulation. The absence of LPV limits the ability to pace the left ventricle endovenously. The diameter of the vein (< 2 mm) and its angulation may also complicate the insertion of the lead. Conclusion: Angiographic analysis of dimensions, tortuosity, number, and angulation of venous tributaries of the CS seems to allow the insertion of commercially available pacing leads in approximately 85% of cases. An increase in this percentage hinges on the development of new, dedicated leads.     

Study of frog (Rana esculenta) proopiomelanocortin processing in the intermediate pituitary Identification of α-melanotropin, β-melanotropin,Lys-γ-melanotropin,and corticotropin-like intermediate lobe peptide

The proteolytic processing of frog (Ranu esculenta) proopiomelanocortin in melanotropic cells of the intermediate pituitary gland has been examined through purification of the mature fragments by reverse-phase high-pressure liquid chromatography and microsequencing of isolated peptides. α-Melanotropin, β-melanotropin, Lys-γ-melanotropin, corticotropin-like intermediate lobe peptide, and hinge peptide have been isolated and chemically characterized. The results show a high preservation in the processing sites of frog proopiomelanotropin when compared to bovine counterparts. They reveal also a great conservation of the processing enzyme equipment of melanotropic cells in tetrapods species. Identification of Lys-γ-melanotropin suggests the occurrence of an endopeptidase able to cleave between two basic residues. On the other hand α-melanotropin does not appear to be N-acetylated, as previously found in the clawed-toad Xenopus laevis, and this feature might distinguish amphibian from mammalian proopiomelanocortin processing.     

Clinical significance of circulating immune complexes in 'lone' cryptogenic fibrosing alveolitis and those with associated connective tissue disorders

The clinical, radiographic and physiological features, and progression rates of forty unselected patients with cryptogenic fibrosing alveolitis (CFA) have been studied in relation to serum immune complexes measured by a C1q binding technique. Twenty (50%) had levels greater than normal. Those with associated connective tissue disorders (twenty-four) had a higher frequency of raised C1q binding than those with ‘lone’ CFA (sixteen) (63% compared to 31%). As observed previously in this group, those with associated disorders also had higher titres of immune complexes. Twelve of thirteen with polyarthritis had immune complexes and a considerably shorter duration of disease compared with those without joint symptoms (P<0.0l). Several other observations suggest that immune complexes are especially associated with earlier disease. These include a trend towards a younger age and a lesser radiographic profusion score; a shorter duration of symptoms in relation to titres of immune complexes amongst those with raised values (P<0.05) and a higher transfer factor coefficient (Kco) (P< 0.02). The relationship between Kco and the presence of immune complexes was still observed when those with ‘lone’ CKA were analysed separately. Other clinical features including sex. severity of dyspnoea and lung volumes did not distinguish those with and without complexes, either for the whole group of patients or when those with and without associated connective tissue disorders were analysed separately. Analysis of eighteen patients followed to death showed no correlation between length of survival from first symptoms and immune complexes, neither was there any clear association with corticosteroid responsiveness and immune complexes. These studies suggest that measurement of serum C1q binding does not contribute substantially to the management of individual patients with cryptogenic fibrosing alveolitis.     

Regional variations of muscle fibre characteristics in m. semitendinosus of growing cattle

The objectives of the present study were to elaborate an intra-muscular profile of metabolic enzyme equipment, contractile and morphometric features along the longitudinal axis of m. semitendinosus at various ages throughout the growth phase. Thirty-seven male Montbeliard cattle, about half of them castrated, were representatively allocated to various slaughter dates, scheduled at 4, 8, 12 and16 months of age. Samples were collected from proximal, medial and distal locations of m. semitendinosus. Isocitrate dehydrogenase (aerobic metabolism) and lactate dehydrogenase (anaerobic metabolism) were measured spectrophotometrically. Contractile muscle type was classified by quantification of myosin heavy chain I isoform proportion using the sensitive enzyme-linked immunosorbent assay. Mean muscle fibre area was obtained on histologically-stained cross-sections utilizing animage analysis system. Our results indicated the existence of a regular intra-muscular pattern of muscle fibre traits along the length of m. semitendinosus, with decreasing glycolytic activities and concomitantly an increase in oxidative capacity towards the distal extremity. The metabolic characteristics were in good agreement with decreasing cross-sectional muscle fibre areas and the slow myosin heavy chain I isoform proportion becoming gradually more abundant from proximal to distal regions of the muscle. Moreover, the observed gradient was found to be closely related to age and diminished with advanced physiological maturity. At the final slaughter age (16 months) no differences among the distinct portions were detected, m. semitendinosus was longitudinally homogeneous in all the characteristics studied This revised version was published online in July 2006 with corrections to the Cover Date.     

Atrial Capture and Dual Chamber Pacing

During dual chamber pacing it is sometimes impossible to assess atrial capture even on the 12-lead ECG. We developed a strategy to identify atrial capture when it is not possible to do so by ECG, and when the ECG shows no evidence of spontaneous or paced atrial activity.     

Toxicity of Smoke During Chair Smoldering Tests and Small Scale Tests Using the Same Materials

Toxicity of Smoke During Chair Smoldering Tests and Small ScaleTests Using the Same Materials. Alarie, Y., Stock, M.F., Matijak-Schaper,M. and Birky, M.M. (1983). Fundam. Appl. Toxicol. 3:619–626.Toxicological evaluation of smoke produced during smolderingchair tests was undertaken by exposing mice to smoke emittedprior to, as well as following, flaming ignition of the chairs.By exposing several groups of mice, using undiluted smoke fromthe room containing the chairs, as well as various dilutionsof the smoke, different levels of acute lethality were obtained.From these experiments, chairs constructed with polyurethanefoam were found to create higher toxic atmospheres than chairsconstructed with polyester or cotton fiber cushions. The samematerials (polyurethane foam, polyester and cotton fibers) werealso thermally decomposed in a small scale system and mice wereexposed to the smoke to evaluate acute toxicity. Again polyurethanefoam was found to produce smoke more toxic than smoke producedby polyester and cotton fibers. Sensory irritation monitoredin mice during the smoldering tests indicated that an intenselevel of irritation was present long before large amounts ofsmoke were generated and long before flaming ignition occurred.The phenomenon of eye, nose and throat irritation would thereforebe the first effect impeding escape attempts of individualsin a fire situation. Sensory irritation was followed by asphyxiationas evolution of carbon monoxide or hydrogen cyanide, or both,occurred. The same pattern of responses was observed with smokegenerated with the small scale decomposition system.     

Synthesis,conformation and reactivity towards p-nitrophenyl acetate of polypeptides incorporating aspartic acid,serine and histidine

Examination of β-carbons coordinates of seryl, aspartyl and histidyl residues in active sites of α-chymotrypsin and subtilisin BPN' shows that a close geometrical arrangement can be obtained in an antiparallel β-structure. Therefore some polypeptides incorporating serine, aspartic acid and histidine, poly (Gly-Ser-Asp-His-Ala-Pro) and poly [(Asp-Leu-Asp-Leu)₁₀, (His-Leu-Ser-Leu)₁], and expected to have some tendency to give rise to an antiparallel β-conformation, have been prepared and studied. The second polymer only adopts a fairly well-defined β-structure in aqueous solution. Catalytic activities of these products towards p-nitrophenyl acetate are not improved as compared to histidine. However kinetic pK of histidine side-chain depends markedly upon the nature of the product, owing probably to a hydrophobic environment effect.