The bone marrow in murine AIDS

In order to increase the understanding of blood cytopenias in HIV infection we have investigated the bone marrow in murine AIDS. C57BL/6 mice infected with the LP-BM5 retrovirus show a decrease in cellularity, numerous haemophagocytic histiocytes, a reduction of all erythroid precursor cells, an increase in eosinophil number and an increase in lymphocytes. Immunostaining with an anti-Pr60gag antibody shows that the majority of bone marrow cells express the viral protein. Thus, the bone marrow in MAIDS has many similarities with the bone marrow from patients with advanced AIDS and may prove useful as a model for therapy aimed at treating blood cytopenias.     

Single and multistate integral friction models

In this note, a single state integral friction model is first proposed, defining separately the Dahl, Stribeck, and microviscous effects. The model is based on an integral closed form solution of the Dahl model. A multistate integral friction model, accounting for the hysteresis behavior with non local memory, has been then derived, combining the Dahl and the Maxwell slip model. The accuracy of the model has been experimentally assessed in friction compensation, both in open and in closed velocity loop.     

Determination of sensory thresholds of Mentha piperita L. essential oil in selected tropical fruit juices and efficacy of sensory accepted concentrations combined with mild heat to inactivate foodborne pathogens

This study determined the compromised acceptance threshold (CAT) and rejection threshold (RT) of Mentha piperita L. essential oil (MPEO) in cajá, guava and mango juices. The MPEO concentrations below the RT values were evaluated alone or combined with mild heat treatment (MHT; 54 °C) to inactivate ≥5-log₁₀ of Escherichia coli O157:H7 and Salmonella Enteritidis PT 4 in the same juices. The CAT of MPEO varied from 0.30 to 0.32 μL mL⁻¹, while the RT was 1.34 or 1.36 μL mL⁻¹ in the tested juices. Only concentrations of MPEO close, or higher than the RT caused ≥5-log₁₀ reductions in the tested pathogens in cajá, guava and mango juices. Combined with MHT, concentrations of MPEO below the RT reduced ≥5-log₁₀ of both pathogens in juices. These findings indicate that MPEO concentrations below the RT in combination with MHT is a feasible preservation technology to ensure the safety of tropical fruit juices.     

Survival of Lactobacillus casei (LC-1) adhered to prebiotic vegetal fibers

This study evaluated the survival of Lactobacillus casei (LC-1) when adhered to four different dehydrated prebiotic fibers. After vacuum drying in oat bran with 9% β-glucan and green banana flour, LC-1 viability was 79% and 76%, respectively. Scanning electron microscopy images revealed no morphological changes in the cells adhered to these fibers, and the addition of trehalose as a cell protectant had a positive and significant effect on the survival of LC-1. At different storage temperatures, oat bran had the highest stability as well as in simulated gastrointestinal conditions, where LC-1 that adhered to the oat bran had greater viability (7.1 log CFU g^? 1) than in the free form (2.4 log CFU g^? 1). In the sensory evaluation, the probiotic oat bran added to a dairy fruit beverage was well accepted by consumers.Industrial relevanceThe diversification of food products and the growing interest in health life requires from food industry innovations and new products for this. Probiotic cultures into non-dairy products is still an innovation and a challenge to the functional food segment. The development of an oat bran with LC-1 adhered is important for the functional food industries because the probiotic can be viable during dehydration and storage at room temperature. In addition the LC-1 is protected under simulated gastrointestinal conditions without compromising sensory acceptability.     

Convex piecewise-linear fitting

We consider the problem of fitting a convex piecewise-linear function, with some specified form, to given multi-dimensional data. Except for a few special cases, this problem is hard to solve exactly, so we focus on heuristic methods that find locally optimal fits. The method we describe, which is a variation on the K-means algorithm for clustering, seems to work well in practice, at least on data that can be fit well by a convex function. We focus on the simplest function form, a maximum of a fixed number of affine functions, and then show how the methods extend to a more general form.     

The influence of molecular weight on the biological activity of heparin like sulphated hyaluronic acids

Sulphated hyaluronic acids having a sulphation degree of 3.5 per disaccharide unit, HyalS3.5, were prepared with different molecular weights corresponding to 21 x 10(3), 320 x 10(3) and 3500 x 10(3). The thrombin inhibition in plasma and in the presence of purified molecules, i.e. fibrinogen, antithrombin III (AT III) and heparin cofactor II (HC II), were studied for the three different MW compounds at different concentrations. The thrombin time in plasma depended on the length of the chain, and the two lower MW HyalS3.5 inhibited thrombin both by direct aspecific interaction and via HC II, whereas the activity of the highest MW compound was mainly related to the electrostatic interaction with HC II. The inactivation of FXa serine protease was only attributed to HyalS3.5-AT III complex.     

MIPAS-ENVISAT limb-sounding measurements: trade-off study for improvement of horizontal resolution

The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) is a limb-scanning spectrometer that has operated onboard the Environmental Satellite since the end of March 2002. Common features of limb-scanning experiments are both high vertical resolution and poor horizontal resolution. We exploit the two-dimensional geo-fit retrieval approach [Appl. Opt. 40, 1872-1875 (2001)] to investigate the possibility of improving the horizontal resolution of MIPAS measurements. Two different strategies are considered for this purpose, one exploiting the possibility (offered by the geo-fit analysis method) for an arbitrary definition of the retrieval grid, the other based on the possibility of saving measurement time by degrading the spectral resolution of the interferometer. The performances of the two strategies are compared in terms of the trade-off between the attained horizontal resolution and the retrieval precision. We find that for ozone it is possible to improve by a factor of 2 the horizontal resolution, which in the nominal measurement plan is approximately 530 km. This improvement corresponds to a degradation of the retrieval precision, which on average varies from a factor of 1.4 to 2.5, depending on the adopted spectral resolution.     

Antithrombotic therapy after coronary stent placement

Subacute stent thrombosis and hemorrhagic complications due to intensive anticoagulant therapy limit the clinical benefit of coronary stenting. Antithrombotic therapy after coronary stent placement has not been standardized yet. From January 1994 to December 1995 a total of 338 Palmaz-Schatz stents were implanted in 285 patients. Procedural success rate was 98.8%. In the initial period, after stent placement, patients were treated with acetylsalicylic acid (ASA) and warfarin (135 patients, Group A), while subsequently, according to the results of other studies, patients were treated with ASA plus ticlopidine (146 patients, Group B). Two hours after sheath removal, Group A patients were treated with intravenous heparin until therapeutic INR (2.5-3.5) was reached; warfarin was stopped 3 months later. In Group B patients 2 hours after sheath removal a treatment with subcutaneous heparin 25,000 IU/die plus ticlopidine 500 mg/die was started. Subcutaneous heparin was maintained until hospital discharge, ticlopidine was stopped after 1 month and ASA was maintained indefinitely. There were no significant differences in baseline characteristics between the two groups. Most patients had unstable angina and in the majority of cases the stent was implanted due to intimal dissection after balloon dilation. Eleven patients had subacute thrombosis of the stent (3.9%): 9 patients were in Group A (6%) and 2 patients were in Group B (1.3%; p = 0.04). Seven patients (6 in Group A, 1 in Group B) were treated with emergency coronary angioplasty and 3 (2 in Group A, 1 in Group B) with coronary bypass; nevertheless 7 patients (6 in Group A, 1 in Group B) had an acute myocardial infarction. Eight patients (6 in Group A, 2 in Group B) had major bleeding due to a large groin hematoma requiring blood transfusion or vascular surgery. In conclusion, after coronary stenting antithrombotic therapy with ASA plus ticlopidine, as compared with anticoagulant therapy, reduces the incidence of both cardiac events and hemorrhagic complications.     

A new platform for Real-Time PCR detection of Salmonella spp., Listeria monocytogenes and Escherichia coli O157 in milk

Intoxications and infections caused by food-borne pathogens represent an increasing public health problem, and diagnostic tests in multiplex format are needed for the rapid identification of food contaminations caused by more than one microbial species. We have developed a multiple PCR-based platform for the simultaneous detection of the widespread milk-associated pathogens Salmonella spp., Listeria monocytogenes and Escherichia coli O157. The assay combines an enrichment step in a medium properly formulated for the simultaneous growth of target pathogens, a DNA isolation method, and a multiplex Real-Time PCR detection system based either on dual-labelled probes (mRT-PCR), or on melting curve analysis (mHRM). The second, producing a distinct peak for each amplification product, allows the qualitative assessment of pathogen presence. Moreover, the internal amplification control (IAC) included in the reaction, ensuring the reliability of results, complies with quality management programmes. Inclusivity and exclusivity were 100% each, with a detection limit of 1 CFU for each pathogen in a total of five 25 ml-aliquots of raw milk, and a duration of two working days.The assay represents an alternative approach for the qualitative detection of the cited bacterial species, suitable for a relatively inexpensive screening of several milk samples, reducing the turnaround time and the workload.