Laser-assisted outpatient septoplasty results on 120 patients

OBJECTIVE: I describe a new outpatient technique of septoplasty, advocated to minimize and simplify surgery under local anesthesia with new laser instruments especially designed. SUMMARY BACKGROUND DATA: This quick technique takes 5 minutes and has a specific clinical application in chronic nasal obstruction due to moderate anterior septal deviation in adults. It is less invasive that traditional septoplasty and potentially more advantageous in terms of decreased patient recovery time, less morbidity, lower medical costs, and faster return to full activity. METHODS: I retrospectively review my experience with 120 patients, from August 1995 to November 1996, with a patient evaluation pre- and postoperatively, at first by a direct interview with clinical examination and acoustic rhinometry, then by a telephone interview with strictly standardized questioning. RESULTS: Of the 120 patients, a surgical success rate of 96% on the nasal obstruction was achieved. Many patients experienced improvement on other symptoms like nasal discharge, frequent sneezing, frequent headaches, recurrent rhinosinusitis, and sense of smell and sleep troubles. Observations comparing pre- and post-operative rhinometries revealed a significant increase of the size of the mean minimal cross-sectional areas (MCA) of the narrow side, at the anterior part of the nose, an increase of the mean nasal cavity volume (NCV), and a decrease of mean nasal airway resistance (NAR). CONCLUSIONS: This new technique appears to be a safe, quick, simple, predictable, bloodless, and virtually painless in-office procedure without side effects. These encouraging good preliminary results must be confirmed by further study and long-term follow-up.     

Specific glucocorticoid binding at different levels of human motor activity

We studied the number of glucocorticoid receptors and dissociation constant in isolated human lymphocytes as well as blood concentrations of hormones produced by the hypothalamic-hypophyseal-adrenocortical system in three experimental series: at normal (17 subjects), decreased (10 subjects, a 360-d head-down bed rest) and increased (8 subjects, physical exercise on bicycle ergometer) levels of motor activity. In the first series we found that the number of glucocorticoid receptors and dissociation constant did not depend on the season, on the age of subjects nor on cortisol concentrations in blood. In the second series we observed the following: at the end of the first month of bed rest the number of glucocorticoid receptors and receptor affinity significantly increased; at the beginning of the third month of bed rest specific glucocorticoid binding significantly decreased and circadian rhythms of adrenocorticotropin and cortisol in blood varied markedly; at the end of the sixth month of bed rest the number of glucocorticoid receptors returned to prebed rest levels and dissociation constant decreased. In the third series physical exercises that induced an activation of the hypothalamic-hypophyseal-adrenocortical system (maximal physical exercises and prolonged submaximal exercises at 70% of maximal oxygen uptake) led to a significant increase in the number of glucocorticoid receptors without changes of dissociation constant. These results indicate that both a decrease and an increase of human motor activity resulted in significant changes of specific glucocorticoid binding which were not influenced by changes of circulating hormone concentrations in blood but by some other factors affected by physical activity.     

Improvement of semiconductor detector characteristics during supercurrent proton irradiation

Volt-ampère characteristics of Si p-type detectors are established to improve after pulse supercurrent irradiation with low energy protons. Appreciable improvement of energy resolution is observed for detectors irradiatied with the supercurrent proton beam within a dose interval from 10¹¹ to 5×10¹² proton cm⁻². Radiational resource of operation increases from 2.3 × 10¹⁰ to 3.7×10 ¹¹ proton cm⁻² for detectors which were pre-irradiated by the supercurrent proton beam.     

Screening for high-affinity ligands to the Src SH2 domain using capillary isoelectric focusing-electrospray ionization ion trap mass spectrometry

A solution-based microscale approach for determination of high-affinity noncovalent complexes from mixtures of compounds is presented, based on capillary isoelectric focusing coupled on-line with electrospray ionization ion trap mass spectrometry. The studies are performed using the src homology 2 domain and tyrosine-phosphorylated peptide ligands as a model system. Tight complexes are formed in solution, preconcentrated up to 2 orders of magnitude and separated on the basis of their isoelectric points. The complexes are then dissociated in the mass spectrometer and the freed ligands identified. Picomole or less amounts of protein reagent are consumed per experiment. Structural information for the ligands involved in tight complex formation may be obtained using the MSn capabilities of the ion trap. The methodology can potentially be used to screen rapidly combinatorial mixtures of compounds for high-affinity ligands.     

Solid–liquid expression from denaturated plant tissue: Filtration–consolidation behaviour

The objective of this study is to investigate the filtration–consolidation behaviour of biological tissue (sugar beet specimens), denaturated by pulsed electric field (PEF) and freezing–thawing pretreatments. The degree of cell membrane damage was evaluated by the tissue electrical conductivity measurement (determination of the cell disintegration index Z). The PEF-treated and freeze–thawed tissues show different structure response on the applied compressive pressure and different filtration–consolidation behaviour. The value of fracture pressure (P_f ≈ 58.5 bar) is the lowest and the value of tissue deformation under fracture (ε_f ≈ 0.46) is the highest for sugar beet tissue treated by freezing/thawing. PEF treatment leads to more rigid and more fragile tissue structure (P_f ≈ 63.8 bar, ε_f ≈ 0.28) than freeze–thawed tissue. Untreated tissue seems to be stronger and less fragile than the PEF-treated tissue (P_f ≈ 84.1 bar, ε_f ≈ 0.37). Different tissue reactions on the loading pressure evidently reflect the difference between microstructures of treated and untreated tissues. The filtration/consolidation behaviour during liquid expression from a sugar beet tissue also depends on the type and degree of structure denaturation. Tissues treated by PEF and freezing/thawing demonstrate two consolidation stages of expression (primary and secondary). However, the freeze–thawed tissue tends to modify the expression mechanism under the higher loading pressure (60 bar) with approach to the primary consolidation behaviour. The simplified semi-empirical consolidation model permits a reasonably good prediction of expression behaviour from the denaturated sugar beet tissue and estimation of consolidation coefficient b under different pressures. The extrapolation of curves b(P) shows the value of hypothetical pressure, P_max ≈ 90 bar at which the consolidation behaviour would be similar to both PEF-treated and freeze–thawed tissues.     

Improvement of anode lifetime by flushing during electrofiltration

The paper is focused on the influence of anode flushing on physicochemical conditions in the anode compartment and anode stability during the electrodewatering in electrofilter press. Kaolin suspensions were dewatered in laboratory filter press with stainless-steel electrodes at electric current density of 80 A/m² and pressure of 2?bar. Two electrodewatering methods were compared: conventional (with filtrate drainage) and innovative (with continuous anode flushing using electrolyte solution). Flushing with neutral electrolyte solution significantly reduced the electrochemical anode corrosion, and can be suggested for the improvement of anode lifetime through a better control of physicochemical conditions during electrodewatering.