[Radial endobronchial ultrasound combined with transbronchial lung cryobiopsy in differential diagnosis of pulmonary infiltrate]. / Radial'naya endobronkhial'naya ul'trasonografiya v kombinatsii s endoskopicheskoi transbronkhial'noi kriobiopsiei v differentsial'noi diagnostike infil'trata v legkom.

Differential diagnosis of pulmonary infiltrates is difficult due to the absence of specific clinical and radiological manifestations. Differential diagnosis of pulmonary infiltrates usually includes the following «triad¼: pneumonia, tuberculosis, lung cancer. Diagnosis of pulmonary tuberculosis is based on microbiological examination of sputum and bronchoscopic respiratory samples - bronchial washing and bronchoalveolar lavage. Efficiency of molecular genetic methods (including express tests) in detecting M. tuberculosis DNA can reach 91-98%. Therefore, treatment may be started without data of microbiological examination. Nevertheless, there are rare cases of false-positive results of PCR in patients with non-tuberculous lung lesions. This aspect often results false diagnosis and delayed verification of true cause of lung lesion. Another adverse effect is associated with anti-tuberculosis therapy. Endoscopic transbronchial lung biopsy and its modern version (transbronchial cryobiopsy) as a minimally invasive diagnostic procedure are performed in such patients. These methods require a sufficiently high experience and qualification of specialist and following such aspects as navigation techniques and balloon bronchial blocking. We present this clinical case as a demonstration of modern possibilities of multimodal navigational bronchoscopic diagnosis with transbronchial cryobiopsy for local pulmonary infiltrate.

Comprehensive Study of the Liquid Expanded-Liquid Condensed Phase Transition in 1,2-Dimyristoyl-sn-glycero-3-phospho-l-serine Monolayers: Surface Pressure, Volta Potential, X-ray Reflectivity, and Molecular Dynamics Modeling.

An integrated approach is applied to reveal fine changes in the surface-normal structure of 1,2-dimyristoyl-sn-glycero-3-phospho-l-serine (DMPS) monolayers at the air-lipid-water interface occurring in a liquid expanded (LE)-liquid condensed (LC) transition. The combination of the Langmuir monolayer technique, X-ray reflectometry, and molecular dynamics (MD) modeling provides new insight into the molecular nature of electrostatic phenomena in different stages of lipid compression. A homemade setup with a laboratory X-ray source (λ = 1.54 Å) offers a nondestructive way to reveal the structural difference between the LE and LC phases of the lipid. The electron density profile in the direction normal to the interface is recovered from the X-ray reflectivity data with the use of both model-independent and model-based approaches. MD simulations of the DMPS monolayer are performed for several areas per lipid using the all-atom force field. Using the conventional theory of capillary waves, a comparison is made between the electron density profiles reconstructed from the X-ray data and those calculated directly from MD modeling, which demonstrates remarkable agreement between the experiment and simulations for all selected lipid densities. This confirms the validity of the simulations and allows an analysis of the contributions of the hydrophobic tails and hydrated polar groups to the electron density profile and to the dipole component of the electric field at the interface. According to the MD data, the dependence of the Volta potential on the area per lipid in the monolayer has a different molecular nature below and above the phase transition. In the LE state of the monolayer, the potential is determined mostly by the oriented water molecules in the polar region of the lipid. In the LE-LC transition, these molecules are displaced to the bulk, and their effect on the Volta potential becomes insignificant compared with the contribution of the hydrophobic tails. The hydrophobic tails are highly ordered in the state of the liquid crystal so that their dipole moments entirely determine the growth of the potential upon compression up to the monolayer collapse.

Noncapillary-wave structure at the water-alkane interface.

Synchrotron x-ray reflectivity is used to study the interface between bulk water and bulk n-alkanes with carbon numbers 6 through 10, 12, 16, and 22. For all interfaces, except the water-hexane interface, the interfacial width disagrees with the prediction from capillary-wave theory. The variation of interfacial width with carbon number can be described by combining the capillary-wave prediction for the width with a contribution from intrinsic structure. This intrinsic structure is determined by the gyration radius for the shorter alkanes and by the bulk correlation length for the longer alkanes.

Mechanism of annexin I-mediated membrane aggregation.

It has been proposed that annexin I has two separate interaction sites that are involved in membrane binding and aggregation, respectively. To better understand the mechanism of annexin I-mediated membrane aggregation, we investigated the properties of the inducible secondary interaction site implicated in membrane aggregation. X-ray specular reflectivity measurements showed that the thickness of annexin I layer bound to the phospholipid monolayer was 31 +/- 2 A, indicating that annexin I binds membranes as a protein monomer or monolayer. Surface plasmon resonance measurements of annexin I, V, and mutants, which allowed evaluation of membrane aggregation activity of annexin I separately from its membrane binding, revealed direct correlation between the relative membrane aggregation activity and the relative affinity of the secondary interaction site for the secondary membrane. The secondary binding was driven primarily by hydrophobic interactions, unlike calcium-mediated electrostatic primary membrane binding. Chemical cross-linking of membrane-bound annexin I showed that a significant degree of lateral association of annexin I molecules precedes its membrane aggregation. Taken together, these results support a hypothetical model of annexin I-mediated membrane aggregation, in which a laterally aggregated monolayer of membrane-bound annexin I directly interacts with a secondary membrane via its induced hydrophobic interaction site.

Coupled capillary wave fluctuations in thin aqueous films on an aqueous subphase.

X-ray scattering and interfacial tension measurements are used to demonstrate the formation of nanometer-thick aqueous films on aqueous bulk subphases from polymer-salt biphase mixtures. X-ray scattering determines a coupling constant that characterizes the coupled capillary wave fluctuations of the liquid-vapor and liquid-liquid interfaces of this thin film. These data also determine an effective Hamakar constant that characterizes the long-range interaction between the interfaces and parameters that characterize the short-range part of the interfacial interaction.