[Forearm osteomusculocutaneous free filet flap for arm reconstruction after amputation as an alternative to shoulder disarticulation]. / Utilisation d'un lambeau libre ostéo-musculo-cutané total d'avant-bras.

We report the case of a 55-year-old woman suffering from a type I neurofibromatosis (also known as Von Recklinghausen neurofibromatosis) who was diagnosed with a high-grade schwannosarcoma of the median nerve, between the upper third and the medium third of the arm, upon contact with the humerus, invading the humeral vessels. The oncologic treatment of this tumour consisted in the amputation of the arm through the surgical neck of the humerus. In order to create a laterothoracic claw, to bring a partial function of the upper limb back, we decided to realize a free fillet forearm flap. This composite flap was composed of the radius and the ulna, all the forearm muscles and the skin of the anterior side of the forearm. A humeroradial plate osteosynthesis was done and the flap was then harvested with the radial pedicle, and anastomosed to the axillar artery. This procedure gave our patient a functional stump, giving back the arm functionality, especially the claw movement.

[Skin diversity: histological study of 140 skin residues, adapted to plastic surgery]. / La diversité de la peau : étude histologique de 140 résidus cutanés, adaptée à la chirurgie plastique.

UNLABELLED: We present in this original article a histological study of surgical skin residues. AIM OF THE STUDY: This study was realized in order to show, in objective way, skin diversity according to sex, age and area, and to illustrate some current surgical practices of our speciality. PATIENTS AND METHOD: Two years along, 141 patients was selected, 69 Men and 72 women. Fifty-four biopsies were realized on the upper extremity, 34 on the trunk and 53 on legs and arms. The histological study was based on two steps; the first one was a classic quantitative study, with measurement of each cutaneous layer, and objective evaluation of elastic density in superficial dermis. The second one was a descriptive histological analysis of each cutaneous area. RESULTS: The results coming from the quantitative analysis, allowed us to establish a classification of all the areas, according to each parameter. These results are globally compliant to the literature. The results of the descriptive analysis, lead us to conclude that it exists a lot of different skins with regional specificities. Then the crossover of the two analyses allowed us to define good practices tricks, in order to choose the best reconstruction technique for each area. CONCLUSION: This study is just a rough draft of a dynamic skin cartography adapted to our surgery. But it allowed us to confirm our basic premise: it doesn't exist only one skin but many skins.

Molecular connectivity methods for the characterization of surface energetics of liquids and polymers.

In the topological approach to structure-property relationships, the molecular structure is described in terms of appropriate weighted graphs to which suitable topological parameters, usually known as molecular connectivity indices, can be associated. Molecular connectivity indices are here applied to the prediction of surface free energy and Good-van Oss-Chaudhury acid-base components of organic compounds. To this aim, some quantitative structure-property relationships (QSPRs) are determined, involving both topological indices and group indicator variables of the customary functional group theory. The semiempirical models obtained to appear satisfactory and show significant advantages with respect to the models based on the purely functional group approach.

Hibernoma of the antero-lateral thigh.

Hibernoma is a rare benign tumour of brown fat. In most cases it presents as a voluminous slow-growing mass in the regions where remnants of brown fat can remain in adults. We report a case of a hibernoma on the thigh and present the diagnostic and therapeutic elements of this type of tumour, whose differential diagnosis of liposarcoma.

The solid surface free energy calculation; II. The limits of the Zisman and of the "equation-of-state" approaches.

This paper follows the "defense" of the Good-van Oss-Chaudhury (GvOC) acid-base approach made in Part I and carries out a detailed analysis of the Zisman critical surface energy and, mainly, of the Neumann equation-of-state (EQS) theory. The analysis is made on both a "practical" and a theoretical basis, trying to highlight the acceptable fitting results of axisymmetric drop shape analysis (ADSA) methods and their independence of the assumed thermodynamic foundations of EQS. Some new and original criticisms of the EQS approach are raised and it is shown that other purely semiempirical models, represented by different fitting equations with the same number of parameters, can represent the data measured by ADSA method with the same goodness as EQS. The equation of state appears as one of many semiempirical approaches for the evaluation of surface free energy of solids. Independent of the previous analysis, the criteria used in ADSA measurements are evaluated and some comments made on them.

The solid surface free energy calculation. I. In defense of the multicomponent approach.

The acid-base approach to the calculation of solid surface free energy and liquid-liquid interfacial tensions is a practical example of application of correlation analysis, and thus it is an approximate approach. In these limits, and provided that wide and well-obtained sets of contact angles or interfacial tension data are used for their computation, surface tension components can be considered as material properties. Although their numerical value depends on the characteristics of the chosen reference material, their chemical meaning is independent on the selected scale. Contact angles contain accessible information about intermolecular forces; using surface tension component (STC) acid-base theory, one can extract this information only making very careful use of the mathematical apparatus of correlation analysis. The specific mathematical methods used to obtain these results are illustrated by using as an example a base of data obtained by the supporters of the equation-of-state theory (EQS). The achievements are appreciably good and the agreement between STC and EQS is discussed.

The effect of surface roughness of microporous membranes on the kinetics of oxygen consumption and ammonia elimination by adherent hepatocytes.

In membrane hybrid liver support devices (HLSDs) using isolated hepatocytes where oxygen is transported only by diffusion to the cells, about 15-40% of the cell mass is likely to be in direct contact with the semipermeable membranes used as immunoselective barriers: quantitative effects of membrane surface properties on the kinetics of hepatocyte metabolic reactions may also affect HLSD performance. In this paper, we report our investigation of the effects of surface morphology of two microporous commercial membranes on the kinetics of oxygen consumption and ammonia elimination by primary hepatocytes in adhesion culture. Isolated rat hepatocytes were cultured on polypropylene microporous membranes with different surface roughness and pore size in a continuous-flow bioreactor whose fluid dynamics was optimized for the kinetic characterization of liver cell metabolic reactions. Collagen-coated membranes were used as the reference substratum. Hepatocyte adhesion was not significantly affected by membrane surface morphology. The rates of the investigated reactions increased with ammonia concentration according to saturation kinetics: the values of kinetic parameters Vmax and K(M) increased as cells were cultured on the membrane with the greatest membrane surface roughness and pore size. For the reaction of oxygen consumption, Vmax increased from 0.066 to 0.1 pmol h(-1) per cell as surface roughness increased from 70 to 370 nm. For the kinetics of ammonia elimination. K(M) increased from 0.23 to 0.32 mM and Vmax increased from 1.49 to 1.79 pmol h(-1) per cell with membrane surface roughness increasing from 70 to 370 nm. Cells cultured on collagen-coated membranes consistently yielded the highest reaction rates. The Vmax values of 0.18 and 2.84 pmol h(-1) per cell for oxygen consumption and ammonia elimination, respectively, suggest that cell functions are also affected by the chemical nature of the substratum.

The interaction of lipodepsipeptide toxins from Pseudomonas syringae pv. syringae with biological and model membranes: a comparison of syringotoxin, syringomycin, and two syringopeptins.

Pseudomonas syringae pv. syringae produces two groups of cyclic lipodepsipeptides (LDPs): the nona-peptides syringomycins, syringostatins, and syringotoxin (ST), and the more complex syringopeptins composed of either 22 or 25 amino acid residues (SP22 and SP25). Both classes of peptides significantly contribute to bacterial pathogenesis and their primary target of action seems to be the plasma membrane. We studied and compared the activity of some members of these two classes of LDPs on red blood cells and on model membranes (monolayers and unilamellar vesicles). All peptides induced red blood cell hemolysis. The mechanism was apparently that of a colloid-osmotic shock caused by the formation of pores, as it could be prevented by osmoticants of adequate size. Application of the Renkin equation indicated a radius of approximately 1 nm for the lesions formed by syringopeptins SP22A and SP25A, whereas those formed by syringomycin E (SRE) had a variable, dose-dependent size ranging from 0.7 up to 1.7 nm. All tested LDPs displayed surface activity, forming peptide monolayers with average molecular areas of 1.2 nm2 (SRE), 1.5 nm2 (SP22A), and 1.3 nm2 (SP25A). They also partitioned into preformed lipid monolayers occupying molecular areas that ranged from 0.6 to 1.7 nm2 depending on the peptide and the lipid composition of the film. These LDPs formed channels in lipid vesicles as indicated by the release of an entrapped fluorescent dye (calcein). The extent of permeabilization was dependent on the concentration of the peptide and the composition of the lipid vesicles, with a preference for those containing a sterol. From the dose dependence of the permeabilization it was inferred that LDPs increased membrane permeability by forming oligomeric channels containing from four to seven monomers. On average, syringopeptin oligomers were smaller than SRE and ST oligomers.

Polymeric membranes for hybrid liver support devices: the effect of membrane surface wettability on hepatocyte viability and functions.

Extracorporeal therapies based on membrane hybrid liver support devices using primary hepatocytes are an interesting approach to the treatment of acute hepatic failure. In such devices, semipermeable polymeric membranes are effectively used as immunoselective barriers between a patient's blood and the xenocytes in order to prevent the immune rejection of the graft. The membranes may act also as the substratum for cell adhesion, thus favouring the viability and functions of anchorage-dependent cells such as the hepatocytes. Membrane cytocompatibility is expected to depend on the surface properties of the polymer, such as its morphology and its physico-chemical properties. In this paper, we report our investigation on the effect of the surface wettability of membranes on hepatocyte viability and functions. Polypropylene microporous membranes were modified to increase their surface wettability and were used as substrata for rat hepatocyte adhesion culture. Isolated hepatocytes were also cultured on collagen as a reference substratum. Hepatocyte viability generally improved as the cells were cultured on more wettable membranes. In agreement with the viability data, the increasing wettability of the membrane surface also improved some metabolic functions.