Wave-function model for the CP violation in mesons.

In this paper, we propose a simple quantum model of the kaons decay providing an estimate of the CP symmetry violation parameter. We use the two-level Friedrich's Hamiltonian model to obtain a good quantitative agreement with the experimental estimate of the violation parameter for neutral kaons. A temporal wave-function approach, based on an analogy with spatial wave-functions, plays a crucial role in our model.

A new definition and properties of the similarity value between two protein structures.

Knowledge regarding the 3D structure of a protein provides useful information about the protein's functional properties. Particularly, structural similarity between proteins can be used as a good predictor of functional similarity. One method that uses the 3D geometrical structure of proteins in order to compare them is the similarity value (SV). In this paper, we introduce a new definition of the SV measure for comparing two proteins. To this end, we consider the mass of the protein's atoms and concentrate on the number of protein's atoms to be compared. This defines a new measure, called the weighted similarity value (WSV), adding physical properties to geometrical properties. We also show that our results are in good agreement with the results obtained by TM-SCORE and DALILITE. WSV can be of use in protein classification and in drug discovery.

Transport in the barrier billiard.

We investigate transport properties of an ensemble of particles moving inside an infinite periodic horizontal planar barrier billiard. A particle moves among bars and elastically reflects on them. The motion is a uniform translation along the bars' axis. When the tangent of the incidence angle, α, is fixed and rational, the second moment of the displacement along the orthogonal axis at time n, ã€ˆS_{n}^{2}〉, is either bounded or asymptotic to Kn^{2}, when n→∞. For irrational α, the collision map is ergodic and has a family of weakly mixing observables, the transport is not ballistic, and autocorrelation functions decay only in time average, but may not decay for a family of irrational α's. An exhaustive numerical computation shows that the transport may be superdiffusive or subdiffusive with various rates or bounded strongly depending on the values of α. The variety of transport behaviors sounds reminiscent of well-known behavior of conservative systems. Considering then an ensemble of particles with nonfixed α, the system is nonergodic and certainly not mixing and has anomalous diffusion with self-similar space-time properties. However, we verified that such a system decomposes into ergodic subdynamics breaking self-similarity.

Geometrical comparison of two protein structures using Wigner-D functions.

In this article, we develop a quantitative comparison method for two arbitrary protein structures. This method uses a root-mean-square deviation characterization and employs a series expansion of the protein's shape function in terms of the Wigner-D functions to define a new criterion, which is called a "similarity value." We further demonstrate that the expansion coefficients for the shape function obtained with the help of the Wigner-D functions correspond to structure factors. Our method addresses the common problem of comparing two proteins with different numbers of atoms. We illustrate it with a worked example.

Association of single nucleotide polymorphisms of interleukin-1 family with atopic dermatitis.

BACKGROUND: Interleukin-1 (IL-1) seems to have an important role in early reactions towards microbes, while its genetic variability could affect this role in atopic patients who have a distressed immunity towards dermatological infections. METHODS: Eighty-nine patients with atopic dermatitis (AD), who were referred to a main referral paediatric hospital, were enrolled in this study. Single nucleotide polymorphisms (SNP) of the following IL-1 cluster genes were assessed in this group of patients: IL-1α -889, IL-1ß -511, IL-1ß +3962, IL-1R Pst-I 1970, and IL-1RA Mspa-I 11100. The results were compared with a group of 140 healthy subjects from the same region. RESULTS: Fourteen percent of the controls had TT homozygous genotype in IL-1R at position Pst-I 1970, while only 2% of the patients with AD had this genotype (p=0.005, OR: 0.14, 95%CI: 0.02-0.64). The CC homozygous genotype was the most common genotype in IL-1α position -889 and IL-1ß at position +3962 in both groups of patients with AD and the controls, while the TC heterozygous genotype was the most common genotype in IL-1ß at position -511 and IL-1R at position Pst-I 1970, with no significant difference between the two groups. CONCLUSIONS: This study showed a significant negative association in the IL-1R Mspa-I 11100 TT homozygous genotype in the patients with AD.

Association between the interleukin 6 genotype at position -174 and atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is a chronic skin disorder of unknown origin that usually manifests for the first time in early infancy. Different types of genetic predisposition and environmental factors seem to be associated with the disease. METHODS: This study was performed to evaluate the frequency of alleles, genotypes, and haplotypes of interleukin (IL) 6 single-nucleotide polymorphisms (SNPs) at positions -174 and nt565 in 89 Iranian children with AD and 139 healthy controls. RESULTS: The G allele was significantly more frequent at position -174 in IL6 in atopic patients than in the healthy controls (P < .001; OR, 2.82). Genotype GG was found at the same position in 71% of the patients; this frequency was significantly higher than the frequency of 30% recorded in the controls (P < .001; OR, 5.60). The GG haplotype of IL6 (-174, nt565) was significantly more frequent in the atopic patients than in the healthy controls (P < .001; OR, 2.99). CONCLUSIONS: A significant increase in the frequency of the G allele and GG genotype at position -174 of IL6 was found in patients with AD, thus suggesting that production of this cytokine is greater in atopic patients.

Association Between the Interleukin 6 Genotype at Position –174 and Atopic Dermatitis

Antecedentes: La dermatitis atópica (DA) es una alteración crónica de la piel de origen desconocido, que habitualmente comienza en la infancia. Diferentes predisposiciones y factores ambientales se asocian a esta enfermedad. Métodos: Este estudio se realizó en 89 niños iraníes con DA para evaluar la frecuencia de alelos, genotipos y haplotipos de polimorfismos genéticos simples (SNPs) de la IL6 en las posiciones 174 y nt565 en comparación con 139 controles sanos. Resultados: Observamos un incremento significativo del alelo G de la IL6 en la posición –174 en los pacientes con DA comparado con el grupo control (p<0.001, OR=2.82). El genotipo GG de la misma posición se encontró en el 71% de los pacientes frente al 30% en los controles (p<0.001, OR=5.60). También se observa un incremento significativo en el haplotipo GG de la IL6 (-174, nt565) en los pacientes con DA comparados con los controles sanos (p<0.001, OR=2.99). Conclusiones: En conclusión observamos un aumento significativo del alelo Gallele y del genotipo GG en la posición -174 de la IL6 en pacientes con DA, lo que podría sugerir un aumento de la producción de esta citocina en los pacientes con DA (AU)

Background: Atopic dermatitis (AD) is a chronic skin disorder of unknown origin that usually manifests for the first time in early infancy. Different types of genetic predisposition and environmental factors seem to be associated with the disease. Methods: This study was performed to evaluate the frequency of alleles, genotypes, and haplotypes of interleukin (IL) 6 single-nucleotide polymorphisms (SNPs) at positions –174 and nt565 in 89 Iranian children with AD and 139 healthy controls. Results: The G allele was significantly more frequent at position –174 in IL6 in atopic patients than in the healthy controls (P<.001; OR, 2.82). Genotype GG was found at the same position in 71% of the patients; this frequency was significantly higher than the frequency of 30% recorded in the controls (P<.001; OR, 5.60). The GG haplotype of IL6 (–174, nt565) was significantly more frequent in the atopic patients than in the healthy controls (P<.001; OR, 2.99). Conclusions: A significant increase in the frequency of the G allele and GG genotype at position –174 of IL6 was found in patients with AD, thus suggesting that production of this cytokine is greater in atopic patients (AU)

Pediatric patients with common variable immunodeficiency: long-term follow-up.

BACKGROUND: Common variable immunodeficiency (CVID) is the most common form of symptomatic primary immunodeficiency disease. It is characterized by hypogammaglobulinemia, increased predisposition to infections, autoimmunity, and cancer. OBJECTIVES: This study was performed to evaluate the clinical and immunological features of a group of pediatric patients with CVID. METHODS: The study population comprised 69 individuals with CVID diagnosed during childhood. RESULTS: The patients were followed up for a mean (SD) period of 5.2 (4.3) years. The mean diagnostic delay was 4.4 (3.6) years, which was significantly lower in patients who were diagnosed recently. Children were classified according to 5 clinical phenotypes: infections only (n=39), polyclonal lymphocytic infiltration (n=17), autoimmunity (n=12), malignancy (n=7), and enteropathy (n=3). Postdiagnosis survival (10-year) was 71%. CONCLUSIONS: The high percentages of pediatric patients with CVID in Iran may be due to the considerable prevalence of parental consanguinity in the region and an underlying genetic background.

Problem of transport in billiards with infinite horizon.

We consider particles transport in the Sinai billiard with infinite horizon. The simulation shows that the transport is superdiffusive in both continuous and discrete time. Also, it is shown that the moments do not converge to the Gaussian moments even in the logarithmically renormalized time scale, at least for a fairly long computational time. These results are discussed with respect to the existent rigorous theorems. Similar results are obtained for the stadium billiard.