The lacZ gene transfer into L929 cells and [14C]-DNA tissue distribution following intraperitoneal administration of new pH-sensitive lipoplexes in mice

The efficacy of lacZ gene transfer into the L929 cell line and a local [l4C]-DNA delivery in male NMRI mice (10-12 weeks old), were studied using new pH-sensitive liposomes, containing phosphatidylcholine/glycyrrhizin (PC/GL) or alpha-tocopherol ester of succinic acid (PC/TSA). The reporter gene (pQE-LacZ plasmid) was transferred into L929 cells using corresponding lipoplexes, 0.5% of cells being transfected. Tissue distribution of Gasserian ganglion neurinoma cell [14C]-DNA fragments and corresponding PC/GL and PC/TSA lipoplexes, were examined following intraperitoneal administration of a 24 h postdose. The [14C]-DNA itself was not detected in any organs at a 1.5 h postdose. The use of PC/GL or PC/TSA lipoplexes considerably changed the biodistribution of [14C]-DNA in mice tissues. The maximal content of [14C]-DNA for both types of lipoplexes was observed in the intestine (50% dose equiv./g) and the spleen (30% dose equiv./g). The content of [14C]-DNA in liver and kidneys was equal to 4 and 10% for liver and kidneys in the case of PC/GL-lipoplexes, and 15 and 6%, for PC/TSA, respectively. Thus, the tropicity for PC/GL-lipoplexes to liver was not detected under i.p. administration.

Photometric methods for determining the optical constants and the thicknesses of thin absorbing films: criteria for precise and unambiguous determination of n, k, and d in a wide spectral range

The application of error analysis within a certain algorithm for the most accurate and unambiguous determination of refractive index n, absorption coefficient k, and thickness d of thin absorbing films in a wide spectral range is illustrated with three examples. Thin films of a dye, Ag, and Au are selected because their optical constants (small n for Ag and Au and considerable variations of n and k for the dye films) along with their thinness make investigating these thin films difficult. The important steps of the algorithm that ensure reliable isolation of the physically correct solutions and maximum accuracy of n and k in the spectral range investigated are also demonstrated.

Photometric methods for determining the optical constants and the thicknesses of thin absorbing films: selection of a combination of photometric quantities on the basis of error analysis

We select the best combinations of spectrophotometric quantities for the most accurate determination of the optical constants, n (refractive index), k (absorption coefficient), and the thicknesses of thin absorbing films. The basic comparative criteria used are the maximum absolute errors in the determination of n, k, and d that result from experimental errors in photometric measurements and in the optical constants of the substrates. We studied all possible combinations of photometric quantities T, T(s)(theta), T(p)(theta), R, R(s)(theta), R(p)(theta), R(m), R(ms)(theta), and R(mp)(theta) at 0 degrees < theta < or = 70 degrees, where T denotes transmission; R, reflection; the subscripts s and p, s- and p-polarized light; m, reflection from a thin film coated upon an opaque substrate; and superscript theta, the angle of incidence of light. The absence of the subscripts s and p implies nonpolarized light; that of the subscript m, a nonabsorbing substrate; and that of superscript theta, normally incident light. The error analysis that is made admits the following conclusions: (1) The best double combinations are (TR), (TR(m)), (TR(p)(70)), and (TR(mp)(70)); (2) the best triple combinations are (TRR(m)), (TRR(p)(70)), (TRR(mp)(70)), (TR(m)R(p)(70)), and (TR(m)R(mp)(70)); (3) the methods indicated above, suitably combined, are quite sufficient to provide the maximum accuracy and reliability of n, k, and d for all practical situations; (4) TRR methods based on measurements with obliquely polarized light are more suitable for thin films with n < 1, such as some metal films; (5) the regions of n, k, and d/lambda with the highest and the lowest accuracies do not overlap in either the TR or the TRR methods. Hence more combinations, preferably all, should be applied for the most accurate determination of n, k (and d), and the errors should be evaluated as a criterion for the best combination.

Analysis of errors in thin-film optical parameters derived from spectrophotometric measurements at normal light incidence

A comparative analysis is made of the errors in deriving the optical parameters (n, refractive index; k, absorption coefficient; d, film thickness) of thin films from spectrophotometric measurements at normal light incidence. The errors in determining n, k, and d by the (TR(f)R(b)), (TR(f)R(m)), (TR(b)R(m)), (TR(f)), (TR(m)), and T(k = 0) methods are compared. It is shown that they are applicable to optical constants of thin films in the n > 1.5, k < 4.5, and d/lambda = (0.02-0.3) range, and their combinations make possible the determination of n and k to an accuracy of better than ?4%. To derive the optical constants in a wide spectral range with high accuracy and isolate the correct physical solutions reliably, one should apply all methods, using the relevant solutions with the lowest errors, as shown in this research, when determining the optical constants of As(2)S(3) and Sb(2)Se(3) films.

Lung injury with pleuropericardial rupture successfully treated by video-assisted thoracoscopy: case report

We present a case of lung injury with pleuropericardial rupture resulting from blunt chest trauma. A conclusive diagnosis and successful treatment was achieved by video-assisted thoracoscopy. The value of diagnostic modalities and the role of video-assisted thoracoscopy in the management of these challenging patients are discussed.

Determination of thin film optical parameters from photometric measurements: an algebraic solution for the (T,R(f),R(b)) method

A new method of analysis for the simultaneous determination of the optical constants and the thickness of thin films is proposed. It requires measurements under normal incidence of the transmission and of the reflections from both sides of a thin film deposited on a nonabsorbing sbstrate. An algebraic inversion technique is developed involving a numerical interpolation procedure in the last step. There are no missing solutions. The physical solution can be isolated by a comparison with some film thickness estimates or by measurements in a wavelength range.