Persistence of Mammary Artery Branches and Blood Supply to the Left Anterior Descending Artery

Background. Partial harvesting of the left internal mammary artery (LIMA) is a widespread technique used during minimally invasive coronary operations performed through a left anterior small thoracotomy. The influence of persisting LIMA branches was investigated to evaluate their effect on the blood flow of the left anterior descending artery.

Methods. Thirty patients, 15 with totally (group A) and 15 with partially (group B) harvested LIMAs, were evaluated. All the patients underwent postoperative angiography, during which a flow map of the LIMA was performed. The average peak velocity and the diastolic-to-systolic peak velocity ratio were recorded. The LIMA graft flow pattern was recorded in the proximal and distal thirds of the artery. Intramammary adenosine (12 to 14 μg) was injected and the average peak velocities before and after injection were calculated.

Results. The average peak velocity was similar in both groups in the proximal and distal thirds of the LIMA (25 ± 7 and 26 ± 5 cm/sec, respectively, in group A versus 27 ± 5 and 25 ± 5 cm/sec, respectively in group B; p = NS). The diastolic-to-systolic peak velocity ratio was similar proximally (0.78 ± 0.3 in group A versus 0.69 ± 0.3 cm/s in group B; p = NS), but not distally (1.72 ± 0.1 in group A versus 0.97 ± 0.3 in group B; p < 0.0005). The LIMA graft flow reserve was similar both proximally and distally (2.6 ± 0.6 and 2.5 ± 0.3 cm/s, respectively, in group A versus 2.6 ± 0.5 and 2.6 ± 0.3 cm/s, respectively, in group B; p = NS).

Conclusions. The persistence of LIMA branches does not influence the blood flow of the left anterior descending artery after acute adenosine-induced myocardial hyperemia. If a left anterior small thoracotomy is used in left anterior descending artery direct revascularization, complete LIMA harvesting is not mandatory and depends on the personal preference of the surgeon.     

The effect of intravenously administered salbutamol on serum potassium in asthmatic and nonasthmatic atopic subjects

The role of adrenergic mechanism in the pathogenesis of allergic disease is controversial. Recent experimental and clinical reports have suggested that -adrenergic blockade impairs and stimulation enhances extrarenal potassium uptake in humans. This led us to study the effect of the intravenous administration of salbutamol, a specific -2-adrenergic agonist, on serum potassium in 9 healthy subjects and in 23 patients with allergic asthma and/or rhinitis. Serum potassium fell significantly and reached a peak decline at the end of venous infusion in all the normal subjects. Seventeen atopic subjects showed a lower or absent serum K⁺ decrement: there was no difference between asthmatic and rhinitic patients. There was no relation among the salbutamol-induced serum potassium decrement, serum glucose increment, blood pressure and heart-rate changes, and nonspecific bronchial reactivity. These findings suggest that -2-adrenergic hyporesponsiveness is present only in some allergic patients.     

Xylitol formation by Candida guilliermondii in media containing different nitrogen sources

The xylose conversion into xylitol by Candida guilliermondii was evaluated in semi-synthetic media supplemented with different nitrogen sources in a ratio C/N equal 25.6. It was noticed that the xylitol yield was around 80% and also that the type of nitrogen source did not influence this bioconversion.     

Identification of the central vestibular projections in man: a positron emission tomography activation study

The cerebral representation of space depends on the integration of many different sensory inputs. The vestibular system provides one such input and its dysfunction can cause profound spatial disorientation. Using positron emission tomography (PET), we measured regional cerebral perfusion with various vestibular stimulations to map central vestibular projections and to investigate the cerebral basis of spatial disorientation. We showed that the temporoparietal cortex, the insula, the putamen, and the anterior cingulate cortex are the cerebral projections of the vestibular system in man and that the spatial disorientation caused by unilateral vestibular stimulation is associated with their asymmetric activation.     

Flow-mediated cell stress induction in adherent leukocytes is accompanied by modulation of morphology and phagocytic function

Leukocytes adherent to the surfaces of both vascular biomaterials and normal blood vessels experience blood flow induced shear stress. The goal of the reported studies was to investigate the effect of fluid flow on the morphology, phagocytic function and stress response induction in adherent immune cells. Shear approximating arterial, venous and intermediate levels were applied onto glass-adherent IC21 macrophages in a temperature-controlled parallel plate flow system. The results indicate that fluid flow induces a shear-dependent physiological stress response in adherent macrophages and that significant morphological changes accompany macrophage responses to shear stress. In addition, arterial flow conditions induce not only significant cell polarisation, but also enhanced phagocytic ingestion in glass-adherent IC21 macrophages. These findings suggest that blood flow induced shear stress may not only be consequent to adherent leukocyte activation, but may also be integral to the regulation of adherent leukocyte behaviour in vivo.     

Follicular lymphoma international prognostic index

The prognosis of follicular lymphomas (FL) is heterogeneous and numerous treatments may be proposed. A validated prognostic index (PI) would help in evaluating and choosing these treatments. Characteristics at diagnosis were collected from 4167 patients with FL diagnosed between 1985 and 1992. Univariate and multivariate analyses were used to propose a PI. This index was then tested on 919 patients. Five adverse prognostic factors were selected: age (> 60 years vs 60 years), Ann Arbor stage (III-IV vs I-II), hemoglobin level (< 120 g/L vs 120 g/L), number of nodal areas (> 4 vs 4), and serum LDH level (above normal vs normal or below). Three risk groups were defined: low risk (0-1 adverse factor, 36% of patients), intermediate risk (2 factors, 37% of patients, hazard ratio [HR] of 2.3), and poor risk ( 3 adverse factors, 27% of patients, HR = 4.3). This Follicular Lymphoma International Prognostic Index (FLIPI) appeared more discriminant than the International Prognostic Index proposed for aggressive non-Hodgkin lymphomas. Results were very similar in the confirmation group. The FLIPI may be used for improving treatment choices, comparing clinical trials, and designing studies to evaluate new treatments.