11 research outputs found
Towards reliable calculations of the correlation function
The correlation function of two identical pions interacting via Coulomb
potential is computed for a general case of anisotropic particle's source of
finite life time. The effect of halo is taken into account as an additional
particle's source of large spatial extension. Due to the Coulomb interaction,
the effect of halo is not limited to very small relative momenta but it
influences the correlation function in a relatively large domain. The
relativistic effects are discussed in detail and it is argued that the
calculations have to be performed in the center-of-mass frame of particle's
pair where the (nonrelativistic) wave function of particle's relative motion is
meaningful. The Bowler-Sinyukov procedure to remove the Coulomb interaction is
tested and it is shown to significantly underestimate the source's life time.Comment: 18 pages, presented at XIth International Workshop on Correlation and
Fluctuation in Multiparticle Production, Hangzhou, China, November 21-24,
200
Sum rule of the correlation function
We discuss a sum rule satisfied by the correlation function of two particles
with small relative momenta. The sum rule, which results from the completeness
condition of the quantum states of the two particles, is first derived and then
we check how it works in practice. The sum rule is shown to be trivially
satisfied by free particle pair, and then there are considered three different
systems of interacting particles. We discuss a pair of neutron and proton in
the s-wave approximation and the case of the so-called hard spheres with the
phase shifts taken into account up to l=4. Finally, the Coulomb system of two
charged particles is analyzed.Comment: 18 pages, 18 figures, revised, to appear in Phys. Rev.
Increased neurogenesis after ACEA and levetiracetam treatment in mouse pilocarpine model of epilepsy
Introduction and objectives. The aim of the study was to asses the impact of long-term therapy with the second generation antiepileptic drug levetiracetam (LEV) with arachidonyl-2’-chloroethylamide (ACEA), a highly selective cannabinoid CB1 receptor agoniston the process of neurogenesis in a mouse pilocarpine model of epilepsy (PILO). Additionally, a relationship was established between the treatment with ACEA in combination with LEV, and hippocampal neurogenesis in mouse PILO brain.
Materials and method. All experiments were performed on adolescent male CB57/BL mice injected i.p. with LEV (10 mg/kg), ACEA (10 mg/kg) and PMSF (30 mg/kg) (phenylmethylsulfonyl fluoride — a substance protecting ACEA against degradation by the fatty-acid amidohydrolase), pilocarpine (PILO, a single dose 290 mg/kg) and methylscopolamine (30 min before PILO to stop the peripheral cholinergic effects of the pilocarpine, 1 mg/kg). The process of neurogenesis was evaluated after10 days treatment with LEV and ACEA.
Results. Obtained results indicated that the combinations of ACEA+PMSF+LEV and ACEA +PMSF increased the total number of total newborn cells compared to the control. Moreover, ACEA+PMSF administered alone and in combination with LEV had a significant impact on neurogenesis increasing the total number of newborn neurons compared to the control group. Neither LEV nor PMSF had a significant impact on the number of proliferating cells and newborn neurons when compared to the control PILO group. In turn, LEV administered alone decreased significantly the number of astrocytes. However,
ACEA+PMSF has demonstrated significant increase of astrocytes compare to control mice.
Conclusions. These data provide substantial evidence that the combination of LEV+ACEA significantly increases the level of newborn neurons in the PILO dentate subgranular zone
A Long-Term Treatment with Arachidonyl-2′-Chloroethylamide Combined with Valproate Increases Neurogenesis in a Mouse Pilocarpine Model of Epilepsy
Rational polytherapy in the treatment of refractory epilepsy has been the main therapeutic modality for several years. In treatment with two or more antiepileptic drugs (AEDs), it is of particular importance that AEDs be selected based on their high anticonvulsant properties, minimal side effects, and impact on the formation of new neurons. The aim of the study was to conduct an in vivo evaluation of the relationship between treatments with synthetic cannabinoid arachidonyl-2′-chloroethylamide (ACEA) alone or in combination with valproic acid (VPA) and hippocampal neurogenesis in a mouse pilocarpine model of epilepsy. All studies were performed on adolescent male CB57/BL mice with using the following drugs: VPA (10 mg/kg), ACEA (10 mg/kg), phenylmethylsulfonyl fluoride (PMSF—a substance protecting ACEA against degradation by fatty acid hydrolase, 30 mg/kg), pilocarpine (PILO, a single dose of 290 mg/kg) and methylscopolamine (30 min before PILO to stop peripheral cholinergic effects of pilocarpine, 1 mg/kg). We evaluated the process of neurogenesis after a 10-day treatment with ACEA and VPA, alone and in combination. We observed a decrease of neurogenesis in the PILO control group as compared to the healthy control mice. Furthermore, ACEA + PMSF alone and in combination with VPA significantly increased neurogenesis compared to the PILO control group. In contrast, VPA 10-day treatment had no impact on the level of neurons in comparison to the PILO control group. The combination of ACEA, PMSF and VPA considerably stimulated the process of creating new cells, particularly neurons, while chronic administration of VPA itself had no influence on neurogenesis in the mouse pilocarpine model of epilepsy. The obtained results enabled an in vivo evaluation of neurogenesis after treatment with antiepileptic drugs in an experimental model of epilepsy
A Long-Term Treatment with Arachidonyl-2′-Chloroethylamide Combined with Valproate Increases Neurogenesis in a Mouse Pilocarpine Model of Epilepsy
Characteristics of 125 <i>S</i>. <i>pneumoniae</i> strains from children who had undergone adenoidectomy for recurrent and/or persistent symptoms of URTIs.
<p>Characteristics of 125 <i>S</i>. <i>pneumoniae</i> strains from children who had undergone adenoidectomy for recurrent and/or persistent symptoms of URTIs.</p
Resistance rate to antibiotics of <i>Streptococcus pneumoniae</i> isolated from children undergoing adenoidectomy for recurrent and/or persistent symptoms of URTIs.
<p>Dark blocks, samples containing PCV10 serotypes (1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F, 23F); grey blocks, samples containing serotypes in PCV13 (3, 6A, 19A additionally to 10-valent vaccine); white blocks, samples containing other serotypes.</p
MLST-based population structure of Polish isolates obtained in 2011 to 2012, constructed using eBURST analysis (S1 File).
<p>The size of the circle (symbolizing STs) corresponds to the number of isolates belonging to a ST. Blue spots indicate the founder of a clonal group. Single-locus variant and double-locus variant links are represented by pink and blue lines, respectively.</p
Molecular Epidemiology of <i>Streptococcus pneumoniae</i> Isolates from Children with Recurrent Upper Respiratory Tract Infections
<div><p>A total of 125 isolates were recovered from adenoids and/or nasopharynx of 170 children aged 2 to 5 from south-east Poland; they had undergone adenoidectomy for recurrent and/or persistent symptoms of upper respiratory tract infections. Pneumococcal isolates were analyzed by phenotyping (serotyping and antimicrobial resistance tests) and genotyping together with the clonality of the pneumococcal isolates based on resistance determinants, transposon distribution and multilocus sequence typing (MLST). Serotypes 19F, 6B and 23F constituted 44.8% of the isolates. Among all of the strains, 44.8% showed decreased susceptibility to penicillin and resistance to co-trimoxazole (52.8%), tetracycline (38.4%), erythromycin (53.6%), clindamycin (52.8%) and chloramphenicol (27.2%) was observed. Tn<i>6002</i> was found in 34.8% of erythromycin-resistant isolates while composite Tn<i>2010</i>—in 16.7% of <i>erm</i>(B)-carrying isolates that harboured also <i>mef</i>(E) gene. Tn<i>3872</i>-related elements were detected in 27.3% of erythromycin-resistant strains. In the majority of chloramphenicol-resistant <i>cat</i><sub>pC194</sub>-carrying isolates (79.4%), ICESp23FST81-family elements were detected. The genotyping showed that pneumococcal population was very heterogeneous; 82 sequence types (STs) were identified, and the most frequent contributed to not more than 8% of the isolates. Nearly 44% STs were novel, each of them was recovered only from one child. Four STs belonged to one of the 43 worldwide spread resistant pneumococcal clones currently accepted by Pneumococcal Molecular Epidemiology Network (PMEN), i.e. Spain 9V-3, Spain 23F-1, Norway NT-42 and Poland 6B-20, accounting for 12 (16.7%) of the 75 nonususceptible isolates, and five STs were single-locus variants of PMEN resistant clones (England 14–9, Spain 9V-3, Spain 23F-1, Greece 21–30, Denmark 14–32), accounting 9 (12%) of nonsusceptible isolates. A few MDR clones belonging to 6B and 19F serotypes found among preschool children emphasizes rather the role of clonal dissemination of local strains in the community than international clones spreading in the increase of resistance among pneumococcal strains.</p></div