Silver nanoparticle monolayer-to-bilayer transition at the air/water interface as studied by the GISAXS technique: application of a new paracrystal model.

An original diffraction model for the analysis of grazing-incidence small-angle X-ray scattering (GISAXS) from the nanoparticle Langmuir films was developed. This model relies on the concept of the 2D hexagonal paracrystal and employs the distorted-wave Born approximation that is relevant for GISAXS measurements at the air/water interface when the angle of incidence is close to the critical value. The model comprises the cases of the close-packed nanoparticle monolayer and bilayer with the AB-type layer stacking. In this way, both the lateral (along the interface) and vertical (normal to the interface) correlations of the nanoparticle positions can be analyzed. The model was applied to an in situ GISAXS study of the formation of a silver nanoparticle Langmuir film during compression at the air/water interface in the Langmuir-Blodgett trough. Spherical nanoparticles of 5.8 ± 0.6 nm diameter were employed. Different compression stages starting from the submonolayer up to the monolayer collapse via bilayer formation were analyzed in terms of the mean lateral interparticle distance, degree of paracrystal disorder, interlayer distance, vertical disorder, and layer-stacking type in the bilayer as well as the ratio between the monolayer and bilayer coverage in the final film. The model developed is applicable to any nanoparticle Langmuir film formed at the air/liquid interface to extract structural parameters on the nanoscale. The particular results obtained have direct implications on the preparation of silver plasmonic templates with "hot spots" for surface-enhanced Raman scattering.

GISAXS analysis of 3D nanoparticle assemblies--effect of vertical nanoparticle ordering.

We report on grazing-incidence small-angle x-ray scattering (GISAXS) study of 3D nanoparticle arrays prepared by two different methods from colloidal solutions-layer-by-layer Langmuir-Schaefer deposition and spontaneous self-assembling during the solvent evaporation. GISAXS results are evaluated within the distorted wave Born approximation (DWBA) considering the multiple scattering effects and employing a simplified multilayer model to reduce the computing time. In the model, particular layers are represented by nanoparticle chains where the positions of individual nanoparticles are generated following a model of cumulative disorder. The nanoparticle size dispersion is considered as well. Three model cases are distinguished-no shift between the neighboring chains (AA stacking), a shift equal to half of the mean interparticle distance (AB stacking) and random shift between the chains. The first two cases correspond to vertically correlated nanoparticle positions across different chains. A comparison of the experimental GISAXS patterns with the model cases enabled us to distinguish important differences between the 3D arrays prepared by the two methods. In particular, laterally ordered layers without vertical correlation of the nanoparticle positions were found in the nanoparticle multilayers prepared by the Langmuir-Schaefer method. On the other hand, the solvent evaporation under particular conditions produced highly ordered 3D nanoparticle assemblies where both laterally and vertically correlated nanoparticle positions were found.

[Successful treatment of hepatocellular carcinoma with All-trans-retinoic acid]. / Hepatocellularis carcinoma eredményes All-transz-retinsav kezelése.

A 44-year-old female patient was admitted to our department with diagnosis of malignant lymphoma. The abdominal USG and CT showed multiple liver lesions with partial portal vein thrombosis, moderately increased alfa-fetoprotein (AFP), ASAT, ALAT (2x normal value), serology was negative for HBV and HCV. Liver transplantation was suggested but refused because of portal vein thrombosis. ATRA (45 mg/m2/day orally) was given on the basis of the assumption that HCC and acute promyelocytic leukaemia share similar oncogenic pathway (alter the RAR alpha and beta receptors). She was gained 15 kg-s and has resumed her work as a teacher for the last 20 months. Abdominal CT showed a complete regression of the intrahepatic tumour.

Skeletal muscle cellularity and glycogen distribution in the hypermuscular Compact mice.

The TGF-beta member myostatin acts as a negative regulator of skeletal muscle mass. The Compact mice were selected for high protein content and hypermuscularity, and carry a naturally occurring 12-bp deletion in the propeptide region of the myostatin precursor. We aimed to investigate the cellular characteristics and the glycogen distribution of the Compact tibialis anterior (TA) muscle by quantitative histochemistry and spectrophotometry. We have found that the deficiency in myostatin resulted in significantly increased weight of the investigated hindlimb muscles compared to wild type. Although the average glycogen content of the individual fibers kept unchanged, the total amount of glycogen in the Compact TA muscle increased two-fold, which can be explained by the presence of more fibers in Compact compared to wild type muscle. Moreover, the ratio of the most glycolytic IIB fibers significantly increased in the Compact TA muscle, of which glycogen content was the highest among the fast fibers. In summary, myostatin deficiency caused elevated amount of glycogen in the TA muscle but did not increase the glycogen content of the individual fibers despite the marked glycolytic shift observed in Compact mice.

[Prevention and treatment of thoracic empyema resulting from traumatic hemothorax]. / A traumás haemothorax után kialakult empyema thoracis megelözéséröl és kezeléséröl.

Authors report on their experiences with the treatment of thoracic empyema developing from the suppuration of haematoma following thoracic injury. In 30 of 82 patients suppuration of the thoracic cavity has developed. 6 of the 30 patients with empyema were treated first in our Department all 6 healed on drainage whereas in 24 patients, admitted from other departments, the following measures were necessary: 2 pleura lavages under the control of thoracoscope, 3 early decortications, 14 decortications, 5 lung resections and decortications with a decrease of the respiratory surface. Attention is called to the necessity of early and adequate treatment which is a prevention of complication (suppuration). Light is given to the factors which most frequently promote suppuration of the thoracic cavity, developing from traumatic haemothorax. Attention is called to secure the necessary personal and material conditions to the preventive treatment.