A functional outcome study comparing total ankle arthroplasty (TAA) subjects with pain to subjects with absent level of pain by means of videofluoroscopy.

BACKGROUND: Total ankle arthroplasty (TAA) subjects often suffer pain on the anteromedial side of their ankle joint. Whether this prevalent pain is caused by a changed motion pattern of the TAA is unclear. Therefore, this study assessed the kinematic differences in the motion of the TAA components during gait, comparing TAA subjects with elevated versus absent levels of pain. METHODS: Eleven TAA subjects (5 with pain vs. 6 without pain), all with unilateral Mobility™ TAA and at least two years post-operation, were recruited and stratified based on standard clinical assessed patient data. The 3D motion of the TAA was assessed by means of videofluoroscopy during level, uphill and downhill walking. RESULTS: The hypothesis that the pain group shows a different kinematic motion pattern than the no pain group could not be confirmed. CONCLUSIONS: The same kinematic motion pattern causes pain in some patients, but not in others. Further investigation concerning ligament stresses is needed.

Selective electrodesorption based atomic layer deposition (SEBALD): a novel electrochemical route to deposit metal clusters on Ag(111).

The possibility of synergic effects of some metals on the catalytic activity of silver led us to study the way to perform controlled deposition on silver. In fact, many metals of technological interest such as Co, Ni, and Fe cannot be deposited at underpotential on silver, and any attempt to control the deposition at overpotential, even at potentials slightly negative of the Nernst value, did not allow an effective control. However, due to the favorable energy gain involved in the formation of the corresponding sulfides, these metals can be deposited at underpotential on sulfur covered silver. The deposition is surface limited and the successive electrodesorption of sulfur leaves confined clusters of metals. The method can also be used to obtain metal clusters of different size. In fact, the alternate underpotential deposition of elements that form a compound is the basis of the electrochemical atomic layer epitaxy (ECALE), and the reiteration of the basic cycle allows us to obtain sulfide deposits whose thickness increases with the number of cycles. Therefore, the successive selective desorption of sulfur leaves increasing amounts of metals.

3-T MRI with phased-array surface coil in the local staging of rectal cancer.

PURPOSE: This study sought to evaluate the diagnostic accuracy of surface-coil 3T magnetic resonance (MR) imaging in the preoperative study of patients with rectal cancer. MATERIALS AND METHODS: Thirty patients with histologically proven rectal cancer underwent surface-coil 3T MR imaging with sagittal, paracoronal and para-axial T2-weighted turbo spin echo (TSE) sequences. Slice thickness was 3 mm without gap, field of view 24 cm, matrix 400 × 512. Images were assessed for infiltration of the rectal wall, perirectal fat and pelvic structures. Tumours were staged according to the TNM system, and the MR imaging results were correlated with histopathology. RESULTS: In the patients who underwent MR imaging before and after radiotherapy (group 1), the diagnostic accuracy of 3T MR imaging was 88% for T2, 94% for T3 and 88% for T4 cancers. In those who underwent surgical treatment without preoperative radiotherapy (group 2), the diagnostic accuracy was 90% for T2, 87% for T3 and 87% for T4 cancers. CONCLUSIONS: The high signal-to-noise ratio coupled with a large field of view enables surface-coil 3T MR imaging to achieve high levels of diagnostic accuracy in the local staging of rectal cancer, and in particular in assessing infiltration of mesorectum and mesorectal fascia.

Production of bacterial cellulose tubes for biomedical applications: Analysis of the effect of fermentation time on selected properties.

Biosynthesis of bacterial cellulose (BC) in cylindrical oxygen permeable molds allows the production of hollow tubular structures of increasing interest for biomedical applications (artificial blood vessels, ureters, urethra, trachea, esophagus, etc.). In the current contribution a simple set-up is used to obtain BC tubes of predefined dimensions; and the effects of fermentation time on the water holding capacity, nanofibrils network architecture, specific surface area, chemical purity, thermal stability, mechanical properties, and cell adhesion, proliferation and migration of BC tubes are systematically analysed for the first time. The results reported highlight the role of culture time on key properties of the BC tubes produced, with significant differences arising from the denser and more compact fibril arrangements generated at longer fermentation intervals.

Confined electrodeposition of CdS in the holes left by the selective desorption of 3-mercapto-1-propionic acid from a binary self-assembled monolayer formed with 1-octanethiol.

Confined electrodeposition can be achieved through the use of suitable templates, by which the electrodeposition occurs in natural or artificial holes of an insulating layer on a conducting substrate. Here, we present the electrodeposition of CdS on the holes left by the selective desorption of 3-mercaptopropionic acid (MPA) from a binary self-assembled monolayer (SAM) formed on Ag(111) with 1-octanethiol (OT). The electrodeposition of a compound is quite demanding, since it requires the right stoichiometry. In addition, the surface underpotential deposition phenomena exploited by electrochemical atomic layer epitaxy (ECALE) technique ensures that the surface available for electrodeposition after the selective desorption is still Ag(111). Parallel electrochemical experiments show that the amount of compound electrodeposited is consistent with this free Ag(111) surface, and the morphological analysis performed both by atomic force microscopy (AFM) and by lateral force microscopy (LFM) confirm the electrochemical data.

In situ scanning tunneling microscopy investigation of sulfur oxidative underpotential deposition on Ag(100) and Ag(110).

Underpotential (UPD) deposition of sulfur from Na(2)S solution in 0.1 M NaOH was studied on Ag(100) and Ag(110) using in situ scanning tunneling microscopy (STM). The cyclic voltammogram on Ag(100) presents two broad peaks, whereas three partial overlapping peaks and a sharper one are observed on Ag(110). STM measurements carried out during the whole UPD process show that progressively more compact structures are formed as the applied potential is scanned toward more positive potentials. More precisely, p(2×2), c(2×6), and c(2×2) were found on Ag(100) at E = -1.25, -1.0, and -0.9 V, respectively. Less definite conclusions can be drawn for the structures of S overlayers on Ag(110). However, the experimental findings are consistent with an incomplete p(2×1) at potentials preceding the sharp peak, and with a c(2×2) structure at E = -0.9 V vs Ag/AgCl, KCl(sat). The coverage values calculated on the basis of the hypothesized structures have been compared with the values obtained from chronocoulometric measurements at the most positive potentials investigated. Thus, the experimental coverage θ = 0.5 coincides with the coverage calculated for the c(2×2) structure found on Ag(110) at E = -0.9 V by STM, whereas the experimental coverage θ = 0.42 suggests that a mixture of structures c(2×6) and c(2×2) is formed on Ag(100).

Modeling of post-traumatic epilepsy and experimental research aimed at its prevention.

Research on the prevention of post-traumatic epilepsy (PTE) has seen remarkable advances regarding its physiopathology in recent years. From the search for biomarkers that might be used to indicate individual susceptibility to the development of new animal models and the investigation of new drugs, a great deal of knowledge has been amassed. Various groups have concentrated efforts in generating new animal models of traumatic brain injury (TBI) in an attempt to provide the means to further produce knowledge on the subject. Here we forward the hypothesis that restricting the search of biomarkers and of new drugs to prevent PTE by using only a limited set of TBI models might hamper the understanding of this relevant and yet not preventable medical condition.

Applications of bacterial cellulose as precursor of carbon and composites with metal oxide, metal sulfide and metal nanoparticles: A review of recent advances.

This mini review is limited to very recent studies (last 5-10 years) on two major issues, concerning: the production and physical/chemical modification of bacterial cellulose (BC), and its transformation into carbon and integrated synthesis of metal oxides (TiO2, ZnO, Fe3O4, etc.), metal sulfide (ZnS, CdS, etc.) and metal nanoparticles (Au, Ag, Pt, Pd, etc.) within bacterial cellulose nanoribbons network. We believe that the crossover of these two domains could be of considerable interest in the view of improving the performance of materials prepared with bacterial cellulose. The diversity of these nanomaterials allows targeting of many very different properties/applications: electrochemical devices, catalysis and photocatalysis, sensors, etc. After an introduction to the most important chemical and physical characteristics of BC, production parameters, and its physical and chemical modifications, we review the use of BC as a precursor of inorganic materials like carbon and composites with metal or inorganic nanoparticles.

Inhibition of dimethyl sulfoxide induced erythropoietic differentiation of murine erythroleukemia cells in culture.

The dimethyl sulfoxide induced erythropoietic differentiation of murine erythroleukemia cells, as determined by scoring benzidine positive cells, is inhibited by mitomycin C at concentrations that have no effect on cell proliferation. The inhibition occurs only when cells are treated with mitomycin C during induction and has a limit value of about 50%, independent of mitomycin C concentration. This limit value does not depend on cell heterogeneity since genetically homogeneous subclones, derived from DS19 clone, show levels of mitomycin C inhibition between 16 and 50%. Treatment with mitomycin C at different times after dimethyl sulfoxide addition shows that cell sensitivity to inhibition is not homogeneous during the induction period; it is maximal between 18 and 24 h from the start of induction and is observed with a concentration of mitomycin C as low as 25 fM. The inhibition of the benzidine positive phenotypic expression appears irreversible since this effect is observed on cells even several generations after those which were actually treated.

Organocatalytic route for the synthesis of propionylated starch.

In recent years acetylated, propionylated and butyrylated starches have received special attention due to their capacity to deliver specific short chain fatty acids (SCFAs) to the colon in a sustained and predictable manner, and thus contribute to maintaining the normal physiologic function of the large bowel and preventing specific diseases. In the current contribution a non-conventional organocatalytic solventless route for the eco-friendly propionylation of corn starch is proposed. The catalyst used in the acylation is a naturally occurring α-hydroxy acid (l-tartaric acid). Propionylated starches with degree of substitution (DS) in the 0.05-1.59 interval were obtained and characterized in terms of chemical structure, morphology, crystallinity, thermal stability and hydrophilicity. Results showed that by the proposed methodology propionylated starch with the DS required for clinical use (i.e. 0.2-0.3) could be obtained within 2-3h of reaction. Characterization results evidenced the progressive loss of crystallinity of starch granules as higher substitution levels were conferred.

Facile synthesis of cobalt ferrite nanotubes using bacterial nanocellulose as template.

A facile method for the preparation of cobalt ferrite nanotubes by use of bacterial cellulose nanoribbons as a template is described. The proposed method relays on a simple coprecipitation operation, which is a technique extensively used for the synthesis of nanoparticles (either isolated or as aggregates) but not for the synthesis of nanotubes. The precursors employed in the synthesis are chlorides, and the procedure is carried out at low temperature (90 °C). By the method proposed a homogeneous distribution of cobalt ferrite nanotubes with an average diameter of 217 nm in the bacterial nanocellulose (BC) aerogel (3%) was obtained. The obtained nanotubes are formed by 26-102 nm cobalt ferrite clusters of cobalt ferrite nanoparticles with diameters in the 9-13 nm interval. The nanoparticles that form the nanotubes showed to have a certain crystalline disorder, which could be attributed in a greater extent to the small crystallite size, and, in a lesser extent, to microstrains existing in the crystalline lattice. The BC-templated-CoFe2O4 nanotubes exhibited magnetic behavior at room temperature. The magnetic properties showed to be influenced by a fraction of nanoparticles in superparamagnetic state.

Modeling of post-traumatic epilepsy and experimental research aimed at its prevention

Research on the prevention of post-traumatic epilepsy (PTE) has seen remarkable advances regarding its physiopathology in recent years. From the search for biomarkers that might be used to indicate individual susceptibility to the development of new animal models and the investigation of new drugs, a great deal of knowledge has been amassed. Various groups have concentrated efforts in generating new animal models of traumatic brain injury (TBI) in an attempt to provide the means to further produce knowledge on the subject. Here we forward the hypothesis that restricting the search of biomarkers and of new drugs to prevent PTE by using only a limited set of TBI models might hamper the understanding of this relevant and yet not preventable medical condition.

Influence of amphotericin B on leucine uptake in 3T3 cells.

By studying the effect of leucine competitors we found that activation of the specific leucine-transport system underlies the enhancement of leucine uptake in mouse 3T3 fibroblast cells induced by sublethal doses of Amphotericin B (synergic effect). The relation of the antibiotic activity and the alteration of the membrane cholesterol interaction with lipids is discussed.

Endopolygalacturonase from Rhizoctonia fragariae. Purification and characterization of two isoenzymes.

An electrophoretically homogeneous preparation of endo-polygalacturonase (poly(1,4-alpha-D-galacturonide)glycanohydrolase, EC 3.2.1.15) from culture filtrates of Rhizoctonia fragariae, a pathogenic agent in strawberry plants, was resolved into two isoenzymes when subjected to isoelectrofocusing in a narrow pH range. The isoelectric points of the two isoenzymes were 6.76 +/- 0.03 and 7.08 +/- 0.05. The two polygalacturonases exhibited similar substrate specificity, pH optimum and pattern of degradation of sodium polypectate. The two enzymes consisted of a single polypeptide chain which had an apparent molecular weight of 36 000 as determined by gel filtration on Sephadex G-100.

Selective gene mutation in MEL cells.

MEL cells, undergoing erythroid differentiation and parasynchronized by dimethyl sulfoxide (DMSO) induction, were irradiated with a 3-s pulse of UV light at sublethal dose. A large number of clones deficient in different gene functions are found in the progeny of the treated cells, if the pulse irradiation is performed 18-24 h from the start of DMSO induction. Kinetics of thymidine incorporation into DNA show that the period of sensitivity corresponds to the S phase. The results show that the activities of the tested genes are differently affected depending on the exact time of cell irradiation. Maximum percent inhibition of cells not expressing glucose-6-phosphate dehydrogenase (G-6-PD) (70%) is produced by irradiating at 20 h from the start of DMSO induction; 6-phosphogluconate dehydrogenase (6-PGD) (55%), and hypoxanthine (guanine) phosphoribosyltransferase (HPRT) (33%), at 21 h; hemoglobin (50%), at 22 h. The time difference in the sensitivity to UV light is highly reproducible and has been exploited to isolate, with high efficiency, cellular clones deficient in any one of the tested functions. Determinations of enzymatic activities on cell lysates show that the expression of tested genes is actually altered in cells that, on the basis of cytochemical tests, appear unaffected by UV irradiation. While the production of mutant clones is observed only during the S phase of the cell cycle, immediate statistical damage of the cellular DNA is produced at all times of irradiation. This finding excludes that the two types of phenotypic alterations, blocked or altered gene expression, both propagated in the progeny of the cells as clonal properties, may derive from a preferential alteration of those functions during the S phase.

Inhibition of MEL cells' capacity to undergo erythroid differentiation by chemicals added during induction.

Erythroid differentiation of murine erythroleukemia (MEL) cells, as induced by dimethyl sulfoxide, can be suppressed by chemicals at very low concentrations, not affecting cell viability and proliferation, if present in the culture medium between 18 and 24 h after addition of the inducer. The effect is apparent on the progeny of the treated cells and is determined, between day 3 and 5 following DMSO induction, as percent value of cells expressing the erythroid phenotype. Cultures showing decreased values are no longer terminal and a large number of clones, incapable of expressing the erythroid phenotype, can be isolated from them. In contrast, induced cultures are terminal if the added chemicals do not decrease the expression of the erythroid phenotype. Incorporation of thymidine into induced cultures reveals that maximal sensitivity of MEL cells to chemicals coincides with DNA duplication. In all affected cells, the inhibition to undergo erythroid differentiation is transmitted from one cell generation to the next.

Inhibition of erythroid differentiation in MEL cells by UV irradiation. Cell cycle and DNA repair activity.

Irradiation with a 3-s pulse of 254 nm UV light has been used to study sensitivity to mutagenic agents of mouse erythroleukemia (MEL) cell cultures in correlation with the cell cycle. A dose of UV irradiation was chosen that had no consequences for cell viability and growth. For this reason phenotypic effects were monitored on the progeny of all cells of the irradiated cultures by scoring those unable to undergo erythroid differentiation upon induction with dimethyl sulfoxide. The very short period of irradiation made it possible to show that MEL cells, synchronized by two sequential blocks of deoxythymidine and one of hydroxyurea (HU), are sensitive to UV irradiation only in a very short period of time at about 60 min after release from HU block. Determinations of deoxythymidine incorporation into DNA show that this time period corresponds only marginally to the initial part of the S phase during which irradiation has no consequences for cell properties. Cells are not sensitive to UV irradiation in G1 and in G2/M unless, immediately after irradiation and for the following 2 h, cultures are treated with 1 mM HU to interfere with DNA repair. Alkaline sucrose gradient analyses show at all tested times that irradiation leads to fragmentation of cell DNA. The data suggest that an immediate increase of deoxythymidine incorporation into DNA following irradiation is not necessary for the efficient repair of damaged DNA. In fact, the percent of cells expressing the erythroid phenotype is normal in the progeny of cells irradiated in G2/M, when TdR incorporation is at a minimum. Repair activities appear then to be mechanistically divided into two phases, (1) recognition labeling of the altered sites and (2) reconstitution of the DNA sequences. The first activity appears to be operative at all phases of the cycle, the second activity is little or not operative in G2/M, possibly delayed to the following G1 period.

Two periods of sensitivity to mutagens in induced Mel cells with different outcomes.

Mouse erythroleukemia (Mel) cells are particularly sensitive to mutagenic agents between 18 and 24 h from the start of induction (Foresti, M.L. Gaudio, G. Geraci and P. Manduca (1986) Inhibition of dimethyl sulfoxide induced erythropoietic differentiation of murine erythroleukemia cells in culture. Cancer Res., 46, 6260-6263). We show here the occurrence of another period of sensitivity during the initial 5 h after the addition of the inducer dimethyl sulfoxide (DMSO) to the culture medium. The sensitivity to the mutagenic action of a sublethal 3-s pulse of UV light (13.5 J/m2) was monitored on the progeny of the irradiated cells at day 5 after the start of induction. The effects were analysed on functions strictly linked to the final expression of the differentiated phenotype: hemoglobin concentration, percent cells producing hemoglobin (%B+), activity of delta-amino levulinic acid dehydrase (ALA-DH) and presence of globins. Each function appeared differently and selectively affected in the progeny of the cells depending on the exact time of irradiation during the period of sensitivity Specifically, cells irradiated at hour 3 after induction show both hemoglobin concentration and ALA-DH activity values increased by a factor 3 over controls. Cells irradiated at hour 5 show an almost complete halt in cell induction and the other tested functions show minimal values. Cells are nearly insensitive to irradiation at later times, until hour 20, after which a second period of sensitivity with peak value at hour 22 occurs at which time hemoglobin concentration in the progeny of irradiated cells is increased by a factor 3 over controls, ALA-DH activity is increased by a factor 15 while percent B+ value is at its minimum. The differential effects of UV irradiation on Mel cell functions in the first and in the second period of sensitivity to mutagens confirm the hypothesis that the consequences of a mutational event are strictly dependent on the functional state of the cell. The 1-5 h period of sensitivity in which Mel cells fix the effects of the mutagen in their genome corresponds to increased thymidine incorporation not correlated with cell duplication.

[Osteotomy of the external cortex of the gonial angle in the correction of mandibular asymmetry]. / Osteotomia della corticale esterna dell'angolo goniale nella terapia delle asimmetrie mandibolari.

BACKGROUND AND AIM: Patients with facial asymmetries undergoing maxillo-mandibular surgery may have residual asymmetries in the gonial region, body and blade of the mandible that call for further surgery. Other patients may present asymmetries of the lower third of the face that are not associated with occlusal alterations, for which there are no indications for maximally osteotomy. In these cases the authors propose using osteotomy of the outer mandibular cortex to resolve the aesthetic defect. METHODS: A retrospective study was made using a clinical and radiographical evaluation of 7 patients undergoing this operation. The follow-up ranged between 3 and 16 months. The study was performed in 4 patients with residual asymmetry after mono or bimaxillary surgery for facial asymmetry and 3 patients with mandibular asymmetry not associated with occlusal alterations. Surgery included the realisation of osteotomy of the outer cortex of the mandibular angle, with repositioning according to set values and synthesis through rigid fixation. The increased gonial diameter, the degree of reabsorption and the cosmetic results were evaluated. RESULTS: Surgery succeeded in recreating a satisfactory facial symmetry without resorting to extraoral incisions, without using alloplastic materials and minimising the harvesting of autologous material. CONCLUSIONS: The proposed technique enabled the asymmetry to be corrected by maintaining the natural marginal morphology, eliminating the risks of infection, extrusion or deplacement that may occur when using alloplastic materials.

[A case of soft tissue alveolar sarcoma localized in the tongue]. / Su di un caso di sarcoma alveolare dei tessuti molli a localizzazione linguale.

Alveolar soft-part sarcoma is a rare form of malignant tumour. It is generally localized at the limb muscles, rarely in the head and neck. Its histogenesis is still uncertain but its specific cellular characters make the diagnosis easier. The case of a woman with an ASPS of the tongue is described. The morphological aspects and the immunohistochemical results seem, according to the data reported in literature, suitable with the diagnosis of alveolar soft-part sarcoma; however, it is difficult to explain the presence of local positivity to specific neuronal enolase.