240 research outputs found
Falcioni L, Gallotta MC, Baldari C, Cardinali L, Campanella M, Ferrari D, Guidetti L, Meucci M. Influence of training status on cardiac and vascular functioning in young recreational and competitive male rowers. Frontiers in Pediatrics, section Pediatric Cardiology
No full textIntroduction: The aim of the study was to investigate the influence of training
status on cardiovascular function in young male recreational and competitive
rowers.
Methods: Ejection duration in percentage to the heart rate period (ED%),
subendocardial viability ratio (SEVR), augmentation index at 75 bpm (AIx75) and
carotid to femoral pulse wave velocity (cf-PWV) of competitive rowers (CR) (age
17.6 ± 4.1 years), recreational rowers (RR) (age 16.7 ± 2.70 years) and athletes
practicing other recreational sports (ORS) (age 15.3 ± 1.4 years) were assessed.
Results: ED% was lower in CR compared to ORS (31.9 ± 3.9% vs. 38.4 ± 4.8%; p =
0.026) and cf-PWV was higher in CR compared to ORS (5.5 ± 1.0 m/s vs. 4.7 ±
0.5 m/s; p = 0.032). SEVR was higher in CR compared to RR and ORS (165.8 ±
33.7% vs. 127.4 ± 30.4% and 128.3 ± 27.8%; p = 0.022) and AIx75 was lower in CR
compared to RR and ORS (−15.7 ± 8.6% vs. 1.2 ± 9.9% and 1.5 ± 9.1; p = 0.001).
Discussion: Healthy, young competitive male rowers reported higher myocardial
performance and better cardiovascular health than recreational athletes.
Interpretations of cf-PWV in competitive rowers should be performed alongside
other cardiovascular indicators
Intracranial facial nerve grafting after removal of vestibular schwannoma
No full textAm J Otolaryngol. 2009 Mar-Apr;30(2):83-8. Epub 2008 Jul 22.
Intracranial facial nerve grafting after removal of vestibular schwannoma.
Bacciu A, Falcioni M, Pasanisi E, Di Lella F, Lauda L, Flanagan S, Sanna M.
SourceDepartment of Otolaryngology, University of Parma, Parma, Italy. [email protected]
Abstract
OBJECTIVE: The objectives of this study were to evaluate outcomes from facial nerve (FN) cable grafting in patients who experienced FN transection during vestibular schwannoma removal and to compare the FN outcomes of patients who underwent FN grafting by using fibrin glue with those of patients who underwent FN grafting by using microsuture.
MATERIAL AND METHODS: We retrospectively evaluated a series of 33 patients in whom FN grafting was achieved either by using microsuture (8 cases) or fibrin glue (25 cases). Immediate repair of the FN was performed in all cases at the time of initial resection. The patients FN function was assessed preoperatively, in the immediate postoperative period, and at 3, 6, 9, and 12 months or more postoperatively using the House-Brackmann grading system. All patients had at least 1-year follow-up.
RESULTS: At 12 months, a House-Brackmann grade III was achieved in 75% of those who underwent cable nerve graft interposition by using microsuture and in 76% of those who underwent cable nerve graft interposition by using fibrin glue. Analysis of final FN function outcomes demonstrated no statistically significant difference in FN outcomes between the 2 groups (P = .891, Mann-Whitney U test; P = .1, Fisher exact test).
CONCLUSIONS: The functional results after FN cable grafting by using fibrin glue exclusively were equivalent to those obtained with microsuture. However, the technique of FN repair by means of fibrin glue is technically simple, less time-consuming, and imparts less trauma on the nerve than does the traditional suture method
Interaction of tributyltin(IV) chloride and related [Bu3 Sn(LSM)] complex with rat leukocytes and erythrocytes: effect on DNA and on plasma membrane
No full textThe discovery of the antitumor activity of cisplatin led several research groups to investigate the possible
therapeutic applications of othermetal-based compounds. Organotin(IV) complexes have been developed
from organotin compounds that were employed in industry and agriculture as stabilizers and pesticides,
respectively. A careful choice of the ligand coordinated to an organotin(IV) fragment can modulate the
activity of the organotin(IV) complex and minimize its drawbacks.With this aim, the tributyltin(IV) complex
[Bu3Sn(LSM)] (LSM= bis(1-methyl-1H-imidazol-2-ylthio)acetate) was synthesized and its in vitro
effects on rat blood cells were compared with those of the analogous tributyltin(IV) compound without
the anionic ligand.
Comet-assay results show that both the tributyltin(IV) chloride (TBTC) and the complex [Bu3Sn(LSM)]
can induce DNA damage in leukocytes, but a stronger effect was observed in the presence of the organotin(
IV) complex. Moreover, lipid-hydroperoxide formation in leukocyte plasma membranes increases
more in the presence of [Bu3Sn(LSM)] compared with TBTC, while TBTC can change the lipid order and
packing of leukocytes and, partially, erythrocyte plasma membranes. The treatment of whole blood with
these two compounds shows a preferential oxidative effect of TBTC on erythrocyte plasma membranes
and erythrocyte oxidative processes, which influence the induction of DNA damage in leukocytes. The
different hydrophobic characters and the different extents of steric hindrance of TBTC and [Bu3Sn(LSM)]
influence the capacity of the two compounds to cross the plasma membrane and affect the pathways that
lead to DNA damage
In vitro effect of AlCl3 on human erythrocytes: changes in membrane morphology and functionality.
No full textAluminum belongs to a group of potential toxic elements capable of penetrating the human body. In this paper, the effect of aluminum concentrations on red blood cell membranes using different fluorescent probes able to localize in various parts of the phospholipid bilayer (TMA-DPH, laurdan and pyrene) were studied. Our results confirm that human erythrocytes exposed to aluminum undergo physico-chemical modifications at the membrane level. A decrease in fluorescence anisotropy of TMA-DPH and in the polarity of the lipid bilayer with a concomitant shift toward a gel phase was observed, and the pyrene excimerization coefficient (kex) increased. Furthermore, the presence of aluminum induced lipid peroxidation and reduced the activity of erythrocyte antioxidant enzymes (SOD, CAT and GSHPx). Al-induced morphological changes on the erythrocyte membrane surface were monitored using atomic force microscopy. These results provide further information on the target of action of different aluminum amounts
Initial growth of Boltzmann entropy and chaos in a large assembly of weakly interacting systems
No full text15 pages.-- PACS numbers: 05.45.−a; 05.60.−k; 05.45.Jn.-- Final full-text version of the paper available at: http://dx.doi.org/10.1016/j.physa.2007.06.036.We introduce a high-dimensional symplectic map, modeling a large system, to analyze the interplay between single-particle chaotic dynamics and particles interactions in thermodynamic systems. We study the initial growth of the Boltzmann entropy, SB, as a function of the coarse-graining resolution (the late stage of the evolution is trivial, as the system is subjected to no external drivings). We show that a characteristic scale emerges, and that the behavior of SB vs t, at variance with the Gibbs entropy, does not depend on the resolution, as far as it is finer than this scale. The interaction among particles is crucial to achieve this result, while the rate of entropy growth, in its early stage, depends essentially on the single-particle chaotic dynamics. It is possible to interpret the basic features of the dynamics in terms of a suitable Markov approximation
Red blood cells as carriers for delivering of proteins.
No full textThe potential use of red blood cells as a carrier system for transport and delivery of pharmacological substances is well documented. Various methods have been attempted for encapsulation of drugs; in this review we evaluate critically all the procedures illustrating their advantages and disadvantages. Moreover, we present kinetic studies of protein encapsulation by moderate hypotonic dialysis, which allows entrapment of molecules with MW less than 50,000 Da with negligible stress of the erythrocyte membrane. Furthermore data reveal that the resealing procedure commonly used is insufficient to completely seal pores of loaded erythrocytes, allowing entrapped proteins with MW less than 12-14,000 Da to escape. However, only 20-30\% of the entrapped material is released, depending on the final cytocrit, while the remaining is associated to the inner membrane or to cytosolic components. Although the method of hypotonic dialysis is known to be the one that minimally affects the biophysical and immunological properties of the red blood cell membrane, the interaction of encapsulated material with cell costituents would need to be further assessed when considering red cells as macromolecular carriers
Encapsulation of proteins into human erythrocytes: a kinetic investigation.
No full textModerate osmotic shocks of human erythrocytes by hypotonic dialysis (0.06 mosmol/kg) induce cell swelling and formation of pores, without causing apparent lysis. Using 125I-labeled macromolecules of different molecular weight and net charge, we followed the kinetics and efficiency of their encapsulation into erythrocytes. After a 20-30 min period of cell dialysis, macromolecules of up to 50 kDa begin diffusing into the swollen cells by a process which can be described by a first-order two-compartment kinetics. Adsorption to the external cell surface was insignificant, while adsorption to the inner membrane surface was substantial (15-20\%) only for positively charged proteins, at physiological pH. After resealing, pores of a 12-14 kDa cut-off might remain open allowing some release of entrapped material (20-30\%), depending on the final cytocrit, while the remaining might be associated with inner membrane or cytosolic components. Although the method of hypotonic dialysis is known to affect minimally the biophysical and immunological properties of red blood cell membranes, the interaction of encapsulated material with cell constituents would need to be further assessed when considering red cells as macromolecular carriers
Oxygen uptake efficiency slope in healthy normal weight young males: an applicable framework for calculation and interpretation
No full textBackground: The oxygen uptake efficiency slope (OUES) is considered a reliable indicator of cardiorespiratory fitness (CRF) in young and clinical populations who cannot achieve maximal effort during a graded exercise test. However, OUES accuracy depends on the data points used for its calculation and it is still not clear if the submaximal OUES can accurately assess CRF in healthy young males.
Objective. We investigated the association between peak oxygen uptake (VO2peak) and peak and submaximal OUES, and the agreement between submaximal OUES and peak OUES in male adolescents and young adults.
Methods. Fifty normal weight healthy participants (age 14-22 years, VO2peak 43.8 ± 7.3 mL·min-1·kg1) performed a graded exercise test on a cycle ergometer, pulmonary gas exchange was assessed using breath-by-breath analysis. VO2peak, and oxygen consumption (VO2) at the aerobic (AerT) and at the anaerobic threshold (AnT) were determined as the 30-second average of the VO2 values. Peak OUES (up to peak) and submaximal OUES (up to AerT and up to AnT) were calculated from the logarithmic relation between VO2 and pulmonary ventilation.
Results. VO2peak showed higher correlations with peak OUES (r=0.80-0.88) than with the two submaximal OUES (r=0.32-0.81). Peak OUES showed higher agreement with OUES up to AnT (r=0.89-0.93; Typical percentage error 5.9%; Intraclass correlation coefficient = 0.89-0.93) than with OUES up to AerT (r=0.39-0.56; Typical percentage error 15.0%; Intraclass correlation coefficient = 0.38-0.56).
Conclusions. The peak OUES is the best indicator of aerobic fitness in healthy males followed by the OUES up to AnT. The OUES up to AnT is a valid alternative to peak OUES
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