Evaluation of a system for chemical sterilization of packages

A system was evaluated for the chemical sterilization of packages, based on its sporicidal efficiency using inoculated Bacillus subtilis inside polyethylene terephthalate (PET) bottles. Different combinations of contact time, temperature and peracetic acid concentrations were tested, delineated according to a factorial planning of 2³. The results, expressed as decimal reduction counts, proved that peracetic acid showed good sporicidal efficiency at 1.2% concentration in the temperature range 30–50°C. With this performance, the tested system can be used to sterilize plastic bottles and other similar packages, achieving a count reduction of spores by up to 10^?7. Copyright © 2004 John Wiley & Sons, Ltd.     

Cardiovascular changes in a group of patients with heredoataxia. Clinical, electrocardiographic and echocardiographic findings

INTRODUCTION: Heredoataxias form a group of degenerative diseases of the nervous system, which are progressive and hand sound in particular families. MATERIAL AND METHODS: Between August 1994 and September 1995. 14 patients diagnosed as having heredoataxia were studied after admission to our hospital. Eight of these had Friedrich's ataxia (group A) and 6 had other types of ataxia (group B). A standard set of investigations were done, including clinical examination, laboratory tests (such as glycaemia and a lipidogram) to evaluate coronary risk factors. A 12 lead electrocardiogram and bidimensional and m mode echocardiogram were also done to detect disorders of conduction, changes in morphology and cardiac function, together with functional cardiovascular and neurological scales. The patients studied were between 14 and 41 years of age. RESULTS: The most frequent cardiovascular symptom was dyspnoea of effort. Changes on the electrocardiogram were seen in 92% of the patients, mainly from Group A (100%) and were due to alterations of ventricular repolarization and non-specific alterations of conduction and of rhythm. Echocardiogram changes were found in 42.8% of the patients, most frequently due to an increase in the myocardial mass of the left ventricle. CONCLUSIONS: Close correlation between age of onset and duration of the illness, and functional cardiovascular impairment was only seen in patients of Group A, in whom there was an earlier onset of the condition.     

The effect of wheat bran on the excretion of cadmium in rats

The influence of wheat bran as a source of dietary fibre on the excretion of ingested cadmium from diet was studied. The cadmium contents in the diets, faeces, urine, liver, kidney and spleen were determined, as well as the weight gains, the relative weights of the cited organs, and the levels of alkaline phosphatase in serum. No evidence is provided that an increasing portion of wheat bran in the diets induced an increase in cadmium excretion. Changes in the studied toxicity parameters were not found.     

Locally advanced adenocarcinoma of the pancreas: current therapeutic modalities

Pancreatic cancer still have bad prognosis. At the time of diagnosis, less than 10% of patients can undergo surgery with an overall 5-year survival rate of less than 2%. For patients with localized pancreatic adenocarcinoma, the combination of radiation therapy and chemotherapy has been shown to control symptoms and to enhance patient survival. This treatment should be proposed to all the patients with good performance status and without icterus. Pain management should be optimized and often need morphinic and co-antalgic (anticonvulsivants, steroids) consumption. The celiac plexus block with alcohol gives an excellent pain relief and should be more frequently used.     

B epitopes and selection pressures in feline immunodeficiency virus envelope glycoproteins

Previous studies showed that purine analogs block with varying efficiency and specificity certain effects of nerve growth factor (NGF) on PC12 cells. These compounds also inhibit protein kinase activities. The analog 6-thioguanine has thus far been shown to inhibit only protein kinase N, an NGF-activated protein kinase, whereas 2-aminopurine also blocks other kinases. In the present study, immunoprecipitates of Trk NGF receptors from PC12 cells (+/- NGF treatment) were assayed for protein kinase activity by using the substrates myelin basic protein and histone HF1 under phosphorylating conditions optimal for protein kinase N and in the presence or absence of purine analogs. Activity was detected and approximately 50-80% was inhibited by these compounds. The purine analog-sensitive activity was maximally stimulated by NGF within 5 min, was partially decreased by 10 min, and still remained over basal levels after 15 h of NGF treatment. Analysis of myelin basic protein phosphorylated by anti-Trk immunoprecipitates revealed an NGF-stimulated increase in phosphothreonine and phosphotyrosine. Phosphorylation of threonine, but not of tyrosine residues, was inhibited by 6-thioguanine, which therefore inhibits a serine/threonine kinase associated with NGF receptor rather than the receptor kinase itself. Neither 2-aminopurine nor 6-thioguanine inhibited the NGF-dependent induction of Trk-associated kinase activity. Our findings thus indicate association of a purine analog-sensitive serine/threonine protein kinase activity with Trk NGF receptors.     

Scale Tests of Smoke Filling in Large Atria

The large Atriums of airports and railway stations facilitate the access to transport vehicles including shopping malls, cultural spaces, etc. For this reason, they are used by an elevated number of passengers and visitors. Numerous malls contain a large atrium too, as a principal access or as a food court, and they usually have high occupant loads. In case of fire, the smoke can affect human health seriously, and people may be unable to reach a safe place before being overcome by the conditions created by the fire. The traditional approach to fire protection by compartmentation is not applicable to these large volume spaces and the ability of sprinklers to suppress fire in spaces with high ceilings is limited. This work evaluated—using scale tests, fire computer modeling and analytical methods—a comparative analysis of the different results obtained for the smoke control in large atria when the smoke filling approach is applied. Smoke layer and plume temperatures have been registered during the scale test—based on the Froude Modeling—and they have been compared opposite to the FDS scale simulation and the FDS large scale simulation. Smoke layer descend has been studied and compared for the scale test, the computer simulations developed and the empirical equations used. The results demonstrated that the evacuation time calculation is conservative when the zone computer model CFAST, the field computer model FDS or the empirical equations are used, although it turns out to be difficult to define the interface height based on the temperatures registered during the scale tests. The zone computer models generate results faster than field computer models or smoke tests, so it would be necessary to develop better calculation algorithms to define the smoke layer interface.

Effect of calcium chloride addition on ice cream structure and quality

The influence of calcium fortification by the addition of calcium chloride on quality parameters of ice cream based on physical properties was investigated, as was the effect of κ-carrageenan at modifying the effects of this calcium fortification. Four ice cream mixes of conventional composition, with added κ-carrageenan (0 or 0.025%) and added calcium chloride (0 or 4.4 g L⁻¹ = 40 mM of added Ca²⁺), were prepared. Modulated temperature-differential scanning calorimetry was used to investigate the effect of calcium chloride on the nucleation temperature, enthalpy of melting, and freezing point depression. The protein composition of 15.4% (wt/wt) reconstituted skim milk powder solutions with or without 4.4 g L⁻¹ added CaCl₂ and in the supernatant after ultracentrifugation was determined. Fat particle size distributions in ice cream were characterized by light scattering. Ice crystal sizes before and after temperature cycling were determined by cold-stage light microscopy. The results demonstrated that the addition of calcium chloride led to a substantial increase in ice crystal sizes and in fat partial coalescence, which were exacerbated by the addition of κ-carrageenan. These results can be explained by the interaction between Ca²⁺ ions and casein micelles, rather than any effects on freezing point depression. The calcium ions led to a more compact micelle, less serum β-casein, and high fat destabilization, all of which would be expected to reduce macromolecular structure and volume occupancy in the unfrozen phase, which led to increased rates of ice recrystallization.