Biomedical subjects

F Alessandrini

Publications and source records attributed to F Alessandrini.

58 records · Page 4Linked to original sources

PubMed1981

Ultrafiltration during open-heart surgery in chronic renal failure.

Ultrafiltration at the end of cardiopulmonary bypass is an important improvement in major cardiac surgery in patients with chronic renal failure and also in dialysis-dependent patients. It has many advantages over pre- and postoperative haemodialysis or peritoneal dialysis. The method, employing disposable equipment, is easy to use, does not prolong total pump time, as it is of short duration, and restores at the end of operation normovolaemia and haematocrit values.

Adult↗

PubMedDate not supplied

Enu mouse mutagenesis: generation of mouse mutants with aberrant plasma IgE levels.

BACKGROUND: The ENU Mouse Mutagenesis Project aims at a large-scale, systematic production of mouse mutants using the alkylating agent ethyl-nitrosourea (ENU). Offspring of mutagenized mice are subjected to a multiparameter screen to detect alterations in various phenotypes with the ultimate goal of identifying novel genes relevant for the expression of the phenotype. Using this approach, we have analyzed plasma IgE concentrations to identify mouse mutants with aberrant plasma IgE levels. METHODS AND RESULTS: ENU-mutagenized male C3HeB/FeJ were mated to wild-type females to produce F1 offspring. F1 animals were analyzed for alterations in their plasma IgE concentrations that showed a dominant mode of inheritance, or bred further to screen for recessive phenotypes. Plasma IgE concentrations were determined by ELISA and a normal range for plasma IgE was established using C3HeB/FeJ wild-type animals. So far we have tested 6568 F1 animals. Repeated testing confirmed a stable aberrant IgE phenotype in 124 animals. To confirm the genetic basis of the observed phenotype, these mice were subjected to confirmation crossing. Currently we have established 9 independent mutant mouse lines (3 with high plasma IgE and 6 with plasma IgE below detection limit) that have been genetically confirmed and additional 24 variant mouse lines are currently undergoing confirmation testing. CONCLUSION: ENU mouse mutagenesis allowed us to generate and identify mouse mutants with aberrant plasma IgE levels, which may be used to characterize novel genes involved in IgE regulation and may serve as animal models for IgE-mediated diseases.

Alkylating Agents↗

PubMedDate not supplied

Pulmonary endothelial cell modifications after storage in solid-organ preservation solutions.

During lung preservation, the vascular endothelium is probably the first site of damage and these lesions are considered the main limiting factor in solid-organ preservation. In the present study, the ultrastructural changes in the endothelial cells of human pulmonary artery hypothermically stored (at 4 degrees C) for 6 and 12 h in Euro-Collins, University of Wisconsin and Ringer-lactate solutions were compared. The arteries obtained from three patients who underwent pneumonectomy were divided into 20 segments and preserved in the three solutions mentioned. The specimens, which were fixed in osmic acid, were examined using transmission electron microscopy. Transmission electron microscopy indicated that the cells stored in the University of Wisconsin solution either for 6 or 12 h were the best preserved, while the most severely damaged cells were those stored in Euro-Collins solution, even after just 6 h. The cells stored in Ringer-lactate showed an intermediate level of damage. The data from an ultrastructural grading scale, which quantified the damage to the cytoplasm, mitochondria and nucleus, were in broad agreement with the general transmission electron microscopy observations. Analysis of variance of the grading scale data showed that there were statistically significant differences between the groups after both 6 and 12 h storage (P < 0.05).

Aged↗

PubMedDate not supplied

When does the lung die? II. Ultrastructural evidence of pulmonary viability after "death".

Lung transplantation as a therapy for end-stage lung disease is limited by the paucity of suitable donors. If lungs could be retrieved from circulation-arrested cadavers (that is, after death), then more donors for lung transplantation might be available. This study was undertaken to determine the time course of ultrastructural deterioration of cellular organelles in pulmonary tissue after circulatory arrest and death and to determine the effect, if any, of postmortem ventilation on the development of these ultrastructural changes. Sprague-Dawley rats were sacrificed and then separated into three groups: (1) controls, from which the right lung was immediately harvested (n = 4); (2) ventilated group, in which mechanical ventilation with 100% oxygen was started after death (n = 15); and (3) nonventilated group (n = 15). In the ventilated and nonventilated groups, the right lung was harvested at 2, 4, or 8 hours after death. Portions of the lung from each rat were examined by electron microscopy, and each specimen was assigned a semiquantitative injury score that was based on nuclear chromatin clumping, mitochondrial degeneration, intracellular edema, and cellular membrane integrity. The lung in all four controls was normal. At 4 and 8 hours postmortem, ultrastructural damage was significantly attenuated in rats with oxygen ventilation compared with those in the nonventilated group. The degree of ultrastructural damage observed in the oxygen ventilation group at 2 and 4 hours postmortem was not significantly different from that of normal controls. Thus, mechanical ventilation with oxygen after death appears to preserve lung ultrastructure and may delay cell death. This study supports the hypothesis that lung transplantation from cadaver donors may be feasible.

Animals↗