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Notes: Structural properties and microwave permeability of CoFeSiB (Co content ≈87 at. %) films prepared by an ion beam deposition technique were investigated as a function of boron content and growth temperature. A microcrystalline phase is obtained for low boron content and substrate temperatures above 80 °C. X-ray rocking curve indicate that the material is textured with 〈111〉 direction perpendicular to the film plane. The dispersion of the 〈111〉 axis is below 6°. Kerr measurements show that the magnetization is oriented in the film plane and has a uniform direction over the sample. Moreover, coercive force Hc is no higher than 0.5 Oe. The gyromagnetic resonance frequency is 2.2 GHz while the initial permeability is 700 along the hard axis and zero along the easy axis. In contrast, when substrate temperature is decreased below 50 °C, the films are amorphous. Lorentz microscopy domain observations and Kerr effect reveal a local dispersion of magnetization. This is related to the higher coercive force observed in the amorphous samples. As a consequence, microwave permeability shows several resonances and is isotropic in the film plane. It cannot be described by the Bloch–Bloembergen model.

Notes: The high frequency permeability of CoNbZr and CoZrMoNi prepared by magnetron sputtering, and of CoFeSiB deposited by ion beam sputtering was investigated. The layers were deposited on thin (8–12 μm) mylar films, and it was therefore possible to induce large tensile stress with moderate force. The permeability of the layers was measured along the stress direction, in a frequency range that allowed the observation of the rotational permeability and the gyromagnetic resonance. The resonance frequency of CoNbZr shifted from 1.4 to over 3 GHz under stress. A simple model assuming that the easy axis is constant over the whole film predicts the evolution of resonance frequency and initial permeability. This model is in good agreement with measurements on CoZrMoNi, and yields a satisfactory estimation of the magnetostriction coefficient. In the case of CoNbZr, a poorer agreement is attributed to the dispersion of local magnetization direction. For very large stress, cracks in the ferromagnetic films are expected to participate to the increase in the anisotropy field. It was observed that the linewidth of the resonance is slightly affected by the stress.

Notes: Injection of N-methyl-D-aspartate (NMDA) or kainate in the striatum of 7-day-old rats induced massive cell loss in the ipsilateral striatum, hippocampus and inner cortical layers. In order to examine whether apoptosis contributes to cell death in this model of excitotoxic injury we examined the progression of internucleosomal DNA fragmentation and changes in cellular ultrastructure. Agarose gel electrophoresis of DNA extracted from the ipsilateral striatum, cerebral cortex and hippocampus clearly showed breakdown of DNA into oligonucleosome-sized fragments, indicative of apoptosis, 12 h post-NMDA injection. In addition, an increase between 12 and 24 h was observed as well as a continuous presence 5 days later. Kainate induced a similar time course of oligonucleosomal DNA fragmentation, but the intensity of the ethidium bromide stained bands was less compared with that observed for NMDA. DNA fragmentation was not detected in animals intrastriatally injected with Tris-HCl or in animals treated with MK-801 [(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohept-5,10-imine hydrogen maleate, 1 mg/kg] 30 min after NMDA injection. MK-801 had no effect on DNA fragmentation induced by kainate. In addition to agarose gel electrophoresis, terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labelling (TUNEL) was used for detection of DNA fragmentation in sections. A gradual increase in the density of both apoptotic and non-apoptotic TUNEL nuclei was found in the anterior cingulate (ACC) and retrosplenial (RSC) areas of the cortex, the striatum, and the CA1 area and dentate gyrus of the hippocampus over the first 24 h post-NMDA or kainate injection. In the contralateral hemisphere hardly any TUNEL nuclei were present and their density was comparable with that in animals injected with vehicle only. In the ipsilateral mammillary nucleus (MN), which showed no signs of acute cell swelling after intrastriatal injection with NMDA, internucleosomal DNA fragmentation was found 24 and 48 h after intrastriatal NMDA injection. Here, the density of TUNEL cells with apoptotic morphology was high at 12 and 24 h post-NMDA injection but returned to control levels by 5 days. Electron microscopy showed cells with a clearly apoptotic morphology in the ACC and RSC and in the MN 24 h after NMDA injection. In the CA1 area of the hippocampus a necrotic, rather than an apoptotic, ultrastructure prevailed, indicating that the TUNEL method stained both apoptotic and necrotic cells. Based on biochemical and morphological criteria this study provides strong evidence that both apoptosis and necrosis are involved in NMDA- or kainate-induced excitotoxic cell death in the neonatal rat brain.

Notes: Children (n = 110) with seasonal allergic rhinoconjunctivitis were randomized to receive either twice daily 0.05% levocabastine eye drops and nasal spray plus twice daily topical placebos or 2% sodium cromoglycate eye drops and nasal spray four times daily for a period of 4 weeks. Patients were required to use the nasal sprays as directed and the eye drops only when required. The results obtained suggest that topical levocabastine is at least as effective as sodium cromoglycate for the treatment of this condition. After 2 weeks treatment the effect of therapy on nasal symptoms was considered to be excellent or good in 72% of levocabastine-treated patients and 54% of patients on sodium cromoglycate (p = 0.009), with corresponding values for ocular symptoms of 81% and 57% in the two groups, respectively (p 〈 0.05). Investigator assessments also revealed that the severity of sneezing and lacrimation were significantly lower in the levocabastine group at this time (p 〈 0.05). After 4 weeks of treatment, patient diary data revealed that levocabastine was at least as effective as sodium cromoglycate with intergroup differences attaining statistical significance in favor of the topical antihistamine for nasal congestion (p 〈 0.05). Both agents were well-tolerated with no significant differences in the incidence or type of adverse reactions in the two treatment groups.

Notes: Background Rhinoviruses (RVs) are believed to cause most asthma exacerbations but their role in the severity of acute asthma and subsequent recovery of airway function is not defined. The importance of atopy in virus-host interactions is also not clear.Objective We postulated that RV infection and atopic skin prick responses influence the severity of asthma exacerbations as measured by peak expiratory flow (PEF).Methods Patients aged 4–12 years admitted with acute severe asthma to a hospital emergency room (ER) were recruited. PEF measurements were obtained and nasal aspirates (NA) were taken. Atopy was diagnosed by skin prick responses to allergen and the presence of RV RNA and respiratory syncytial virus (RSV) RNA in NAs was detected using validated PCR assays. Patients were restudied after 6 weeks and after 6 months.Results Fifty children with acute asthma (mean age±SD, 7.4±2.7) were enrolled; atopy was present in 37 (74%). RV RNA was detected in 41 (82%) and RSV RNA in six (12%) subjects. After 6 weeks 41 patients were restudied and RV RNA was again detected in 18 (44%). RV RNA was detected after 6 months in four of 16 patients restudied (25%; P=0.008 vs. ER) and in two of nine children from a control group with stable asthma (22%; P=0.009 vs. ER). Overall PEF measurements were reduced in asthmatics admitted to ER (% predicted, 63.4±16.4%) but did not differ between patients with RV RNA, RSV RNA or neither virus present. In subjects with RV RNA detectable in ER and after 6 weeks, measurements of PEF in ER were significantly lower than in patients in whom RV RNA was present in ER but absent after 6 weeks (P=0.009). Regression analysis linked persistence of RV RNA, but not skin prick responses to allergen, to severity of PEF reductions in ER.Conclusion RV RNA was detectable in 〉40% of asthmatic children 6 weeks after an acute exacerbation. Asthma exacerbations were more severe in patients with persistence of RV RNA suggesting that the severity of acute asthma may be linked to prolonged and possibly more severe RV infections.

Notes: The influence of two different types of language therapy was investigated by assigning 32 patients to three groups: 10 patients were treated with a Systematic Therapy program for Auditory Comprehension Disorders (group 1), 11 patients received conventional stimulation therapy (group 2), and the other 11 patients received no treatment at all (group 3). Language recovery in the three groups was examined with a test battery consisting of two parts: Part I consisted of 3 subtests for auditory comprehension, which were also used as practice materials in the treatment program given to the patients of group 1; Part II contained 8 tests for auditory comprehension, reading comprehension, and oral expression, the items of which were not used as practice materials in either of the two treated groups. Although the influence of age, time post onset, and severity of the receptive disorder were controlled by multiple regression analysis, it was found that the differences between the three treatment conditions were far from significant on almost all evaluation tests of Part II, as well as on the evaluation tests of Part I. On the basis of these results it was concluded that neither the Systematic Therapy program for Auditory Comprehension Disorders nor the conventional stimulation therapy had any clear effect on the recovery process of the treated patients in groups 1 and 2. Some possible reasons for the failure to demonstrate significant differences in language gains between the three therapeutic conditions are discussed.