Long-term follow-up of nasal immunotherapy to Parietaria: clinical and local immunological effects

BACKGROUND: Local nasal immunotherapy (LNIT) with extracts in powder has been demonstrated clinically effective and devoid of side-effects in several controlled trials; nevertheless, no data concerning the long-term effects of LNIT are presently available. METHODS: In a recent double-blind, placebo-controlled study of LNIT to Parietaria pollen we observed, by means of specific nasal provocation test (SNPT) that LNIT is able to modify the local allergic inflammatory response. In the present study we followed up the same patients in open fashion for 2 further years. RESULTS: The results confirmed the clinical efficacy of LNIT and showed that it is strictly dependent on pre-seasonal administration: in fact, after LNIT discontinuation a clinical relapse was observed. A certain long-lasting protective effect on SNPT parameters (nasal symptoms and neutrophils infiltration) was also observed, whereas an increase of eosinophils count and ICAM-1 expression on nasal epithelial cells appeared as possible markers of clinical relapse. CONCLUSION: The present study suggests that pre-seasonal LNIT can be taken in consideration in selected subjects as prophylactic treatment for pollen-induced rhinitis. In addition, the results obtained provide informations about the duration of clinical efficacy and add data about the local allergic inflammation and its modulation.     

Why concept lattices are large: extremal theory for generators,concepts, and VC-dimension

Abstract

A unique type of subcontexts is always present in formal contexts with many concepts: the contranominal scales. We make this precise by giving an upper bound for the number of minimal generators (and thereby for the number of concepts) of contexts without contranominal scales larger than a given size. We give an interpretation of this bound in terms of the Vapnik–Chervonenkis dimension of the concept lattice. Extremal contexts are constructed which meet this bound exactly. They are completely classified.     

Influence of lipid peroxidation on lipoprotein secretion by isolated hepatocytes

Isolated rat liver cells have been exposed to 3 different lipid peroxidation-inducing agents, CCl₄, FeCl₃ and cumene hydroperoxide, and the rates of malonaldehyde production and of lipoprotein secretion have been compared. Results indicate that it is possible to induce a high degree of lipid peroxidation without inducing strong changes in lipoprotein secretion. Only in CCl₄-poisoned hepatocytes is lipoprotein secretion strongly impaired. In this experimental condition, the effect of free radical scavengers, or inhibitors of lipid peroxidation, has been studied; the degree of covalent binding of CCl₄ metabolites to hepatocyte proteins, as well as the behavior of both lipid peroxidation and lipoprotein secretion, have been evaluated. Promethazine and propyl gallate prevented malonaldehyde production, but neither agent reduced covalent binding nor improved secretion. Menadione, on the contrary, besides inhibiting malonaldehyde production, decreased covalent binding and protected against the impairment of secretion. These data lead to the conclusion that covalent binding of CCl₄ metabolites, rather than lipid peroxidation products, accounts for the derangement of lipoprotein secretion in CCl₄-poisoned liver cells. Presented in part at the ISF-AOCS World Congress, New York, April 1980.     

Morphological aspects of testes and sperm ultrastructure in the "symphyta" Digelasinus diversipes kirby 1882 (hymenoptera: Argidae: Dielocerinae)

In Digelasinus diversipes, spermatozoa are maintained in bundles, with 74 spermatozoa on average, in the seminal vesicle. These spermatozoa are very short (20 μm) and consist of a head and flagellum. The head includes an acrosome (perforatorium covered by the acrosomal vesicle) and a nucleus. A regular electron-lucent region separates the acrosomal vesicle from the perforatorium, which is inserted parallel to the anterior ending of the nucleus. The small flagellum is composed of two symmetrical mitochondrial derivatives, a centriolar adjunct, an axoneme (9 + 9 + 2), and two accessory bodies. The centriolar adjunct begins above the posterior end of the nucleus and ends covering the anterior tip of two mitochondrial derivatives. In the terminal region of the axoneme, the central microtubules terminate first. The presence of a subacrosomal space, a short mitochondrial derivative diameter, and a short spermatodesm is the ultrastructure characteristics of spermatozoa shared by all "symphyta" species. Differences in the insertion of the perforatorium into the nucleus and the position of the centriolar adjunct distinguish Dielocerinae and the Arginae studied previously. The number of spermatozoa per cyst is variable. Furthermore, additional characteristics that had not been described for "symphyta" were also found, such as the number of follicles per testis.     

A Koszul Decomposition for the Computation of Linear Syzygies

In the present paper some algorithms are proposed for computing Linear Strands and Betti Numbers of graded modules over polynomial rings. These algorithms are based on a block-decomposition, induced by the Koszul syzygies, of the linear systems involved with the Hilbert's method for computing syzygies. Some further optimizations are suggested and applied by the authors to an implementation they have developed of the algorithms. Received: January 10, 2000; revised version: July 17, 2000     

Effect of different copolymers (hydrogenated and non-hydrogenated, with different molecular weights and different content of styrene) in the compatibilization of PS + PP (80+20) polyblend

We have studied the effect of the addition of different compositions of several styrene / butadiene / styrene (SBS) triblock copolymers, hydrogenated and non-hydrogenated, with different molecular weights and different content of styrene, on the PS + PP (80+20) polyblend. We have determined the influence of these parameters on thermal and mechanical properties as well as on the observed morphology. As the composition of the hydrogenated copolymer or the copolymer with a similar content of styrene and butadiene was increased, the dispersion of particles increased, lowering remarkably their size and producing this way a better interfacial adhesion in the blend. Excluding the copolymer with similar content of styrene and butadiene in its structure, the rest of the copolymers show a strong tendency to form micelles or mesophases in the matrix as the amount of copolymer increases, improving some mechanical properties such as impact strength but deteriorating others like the yield and break stresses. On the other hand, the presence of compatibilizers, at any composition, does not have any effect on the thermal parameters of the blend. Nevertheless, the presence of PS, amorphous and the majority component in the blend, affects the crystallization process of PP, enhancing in a wide temperature range (from 125 °C to 40 °C) its crystallization process. Received: 14 November 2000 / Reviewed and accepted: 15 November 2000     

Thermodegradative and morphological behavior of composites of HDPE with surface-treated hydroxyapatite

In the present work, the thermodegradative and morphological behavior of composites of high-density polyethylene and surface-treated hydroxyapatite (HDPE/HA) were studied. Composites were prepared with HDPE, 30 wt% of HA and 2 phr of an ethylene–acrylic acid copolymer (20 wt% of acrylic acid) (EAA) and melt-blended in an internal mixer at 160 °C and 50 rpm. Two sets of composites filled with different surface-treated hydroxyapatite (STHA) were prepared: one HA sample was pretreated with ethylene–acrylic acid copolymer (STHA₁) and the other one with acrylic acid (STHA₂). Thermogravimetric analyses were carried out to evaluate the thermal stability of the composites. The activation energies (Ea) were determined using a numerical method based on the Invariant Kinetic Parameters (IKP). The thermal decomposition of the HDPE/HA composites showed an Ea value of 330 kJ/mol. On the other hand, HDPE/HA/EAA and HDPE/STHA₁ composites showed a sudden decrease in Ea (272 and 270 kJ/mol, respectively). The HDPE/STHA₂ composite exhibited an Ea value of 313 kJ/mol, slightly lower than that of the HDPE/HA composite. Additionally, with the presence of EAA copolymer and acrylic acid in the composites, the nucleation and nucleus growth kinetic-model probabilities decreased compared to those of the HDPE/HA composite. However, there was an increase in the probability of the reaction order of the model. This behavior could be attributed to the morphology of the composites and to the addition of a less thermally stable component, i.e. EAA copolymer and acrylic acid. On the other hand, due to the interaction polymer/surface-treated filler, an increase in the Young Modulus and the tensile strength was observed.     

Quantifying soil organic carbon in forage-based cow–calf congregation-grazing zone interface

Recent concerns about global warming due to accumulations of atmospheric CO₂ have encouraged the achievement of better understanding of the roles of animal agriculture in mitigating CO₂ emissions. Grazing can accelerate and alter the timing of nutrient transfers, and increase the amount of nutrients cycled from plant to soil. Our reason for conducting this study is to test whether cattle congregation sites (CCS) typical on most Florida ranches, such as mineral feeders (MF), water troughs (WT), and shaded areas (SA) have higher soil organic carbon (SOC) than in other locations of pasture under foraged-based system. Baseline soil samples around the congregations zones (MF, WT, and SA) and grazing zones in established (>10 year), grazed cow–calf pastures were collected in the spring and fall of 2003, 2004, and 2005, respectively. Soil samples were collected from two soil depths (0–20 and 20–40 cm) at different locations around the CCS following a radial (every 90 degrees: N, S, E, and W) sampling pattern at 0.9, 1.7, 3.3, 6.7, 13.3, 26.7, and 53.3 m away from the approximate center of MF, WT, and SA. The levels of SOC varied significantly with CCS (P ≤ 0.001), distance away from the center of the CCS (P ≤ 0.05), sampling depth (P ≤ 0.001), sampling year (P ≤ 0.001) and the interaction of CCS and soil depth (P ≤ 0.001). Sampling orientations did not significantly affect the levels of SOC. The SA sites had the highest level of SOC of 3.58 g kg⁻¹, followed by WT sites (3.47 g kg⁻¹) and MF sites (2.98 g kg⁻¹). Results of our study did not support our hypothesis that cattle congregation sites typical on most ranches, such as MF, WT and SA, may have higher concentrations of SOC. The levels of SOC (averaged across CCS) within the congregation zone (3.42 g kg⁻¹) were not significantly (P ≤ 0.05) different from the concentrations of SOC at the grazing zone (3.16 g kg⁻¹).