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Background The resistance of melanoma cells to cisplatin restricts its clinical use. Therefore, the search for novel tumor inhibitors and effective combination treatments that sensitize tumor cells to this drug are still needed. We purified macrovipecetin, a novel heterodimeric C-type lectin, from Macrovipera lebetina snake venom and investigated its anti-tumoral effect on its own or combined with cisplatin, in human melanoma cells. Methods Biochemical characterization, in vitro cells assays such as viability, apoptosis, adhesion, migration, invasion, Western blotting and in silico analysis were used in this study. Results Macrovipecetin decreased melanoma cell viability 100 times more than cisplatin. Interestingly, when combined with the drug, macrovipecetin enhanced the sensitivity of SK-MEL-28 cells by augmenting their apoptosis through increased expression of the apoptosis inducing factor (AIF) and activation of ERK1/2, p38, AKT and NF-κB. Moreover, macrovipecetin alone or combined with cisplatin induced the expression of TRADD, p53, Bax, Bim and Bad and down-regulated the Bcl-2 expression and ROS levels in SK-MEL-28 cells. Interestingly, these treatments impaired SK-MEL-28 cell adhesion, migration and invasion through modulating the function and expression of αvβ3 integrin along with regulating E-cadherin, vimentin, β-catenin, c-Src and RhoA expression. In silico study suggested that only the α chain of macrovipecetin interacts with a region overlapping the RGD motif binding site on this integrin. Conclusions We validated the antitumor effect of macrovipecetin when combined, or not, with cisplatin on SK-MEL-28 cells. General significance The presented work proposes the potential use of macrovipecetin and cisplatin in combination as an effective anti-melanoma treatment.

In this paper a new strategy for observing and analyzing a basketball match using video processing techniques to identify the game systems of a team is described. The system tracks players' positions during the match. At the outset, three video streams from three fixed cameras are available, each processed separately to deliver measures of the players' positions from different available views. Each treated view includes foreground detection and a bounding-box tracker designed to contain the pixels representing each player. During the multi-view process, measurements from different views are synchronized to enable identification of the same player when the player is visible simultaneously on several cameras. These measurements are combined in order to obtain the players' positions as well as their updated positions through the images. The position thus obtained is exploited in a database containing the representative points (coordinates) of all the players, who form a polygon. The analysis of a game system is thus simply the analysis of the deformation and movement of this polygon during the match. Comparative indicators of the two teams are defined, along with an indicator which represents the opinion of an expert in the sport (action code). Statistical tools are exploited with the objective on the one hand of identifying correlations and relationships between different indicators, and on the other hand of identifying the game system adopted by comparing the expert opinion and the results of the established heuristic models.

Small-Angle Neutron Scattering (SANS) has been an ever-growing characterization method for nanoscale materials over the past 25 years. Improved instrumentation and new and judiciously chosen in situ sample environments have fueled this drive. Examples are facilities to control temperature, introduce shear fields and, more recently, to vary pressure. Controlled temperature and temperature jump experiments have been of great value for studies of miscibility and kinetics of phase separation in polymer mixtures. In situ shear measurements added another dimension to rheological studies of materials such as copolymers, micelles and colloid systems. There have been many investigations of the effects of a shear field on structures and on thermodynamics. Over the past five years, the introduction of a controlled pressure/temperature facility has led to a good deal of research on SANS from polymers and other soft materials under pressure. Representative efforts using the 30m NG-3 SANS instrument at NIST ar...

A neutron spin filter based on transmission through nuclear-spin-polarized 3He gas has been applied to polarization analysis of small angle neutron scattering (SANS). Such spin filters, which are based on the large spin dependence of the absorption of neutrons by 3He, make SANS polarization analysis possible because of their large angular acceptance. In the present experiment, a 3He-based analyzer was employed to separate nuclear scattering into its coherent and spin-incoherent components. Polarized 3He analyzers were prepared by two different optical pumping methods and installed on the NG3 SANS instrument at the NIST Center for Neutron Research (NCNR). Measurements were taken on cellophane tape and silica gel, for which the scattering is almost completely incoherent and coherent, respectively, and on a combined sample. For the combined sample, separation of the coherent part from the incoherent part was successfully demonstrated using polarization analysis.

Two high-resolution, general-purpose, small-angle neutron scattering instruments have been constructed at the National Institute of Standards and Technology's Center for Neutron Research. The instruments are 30 m long and utilize mechanical velocity selectors, pinhole collimation and high-data-rate two-dimensional position-sensitive neutron detectors. The incident wavelength, wavelength resolution and effective length of the instruments are independently variable, under computer control, and provide considerable flexibility in optimizing beam intensity and resolution. The measurement range of the instruments extends from 0.0015 to 0.6 A−1 in scattering wavevector, corresponding to structure in materials from 10 A to nearly 4000 A. The design and characteristics of the instruments, and their modes of operation, are described, and data are presented which demonstrate their performance.

The structure of ultrathin cellulose acetate membranes, known as active layer membranes, has been investigated using small-angle neutron scattering. These membranes are known to have structural and functional similarity to the surface or "skin" layer in commercial reverse-osmosis (RO) membranes and hence are useful model systems for understanding the structure of the RO membrane skin layer. Active layer membranes were studied after swelling them with either DzO or CD30D. The results in both cases clearly indicated the presence of very small (10-20 A) porous structures in the membrane. The presence of such pores has been a subject of long-standing controversy in this area. The data was analyzed using a modified Debye-Bueche analysis and the resultant membrane structure was seen to agree well with structural information from electron microscopic studies. Finally, a possible explanation for the differences in scattering observed between the DzO swollen membranes and the CD30D swollen membranes has been presented.

Small-angle neutron scattering measurements were taken from high molecular weight (1.95 X lo6) deuterated polystyrene in dioctyl phthalate solution at low concentration (3 % weight fraction) under steady shear with rates ranging from the quiescent condition (0 s-l) to 1100 s-l at room temperature (22 OC). The scattered intensity increased drastically beyond a characteristic shear rate (+c = 57 9-1) similar to the increase following a temperature drop from the one-phase region (ambient temperature) to the two-phase region in this upper critical solution temperature system. The cloud point is estimated to be a few degrees lower than 14 OC which is the cloud point for protonated polystyrene in dioctyl phthalate at this molecular weight and concentration. On the basis of this analogy, the random-phase approximation (RPA) approach (the Zimm inverse scattering formula) was used along with a swollen radius of gyration in the Debye function to analyze the data and extract a statistical segment length b and a polymer-solvent interaction parameter xp. The segment length was seen to increase slightly, indicating a slight increase in chain volume beyond +c, while the interaction parameter showed a dramatic increase up to the 'spinodal" value +* = 280 8-1 where the RPA breaks down, therefore giving nonreliable values. This data treatment method has no justification on physical grounds: it is merely a way to quantify our observations since specific models that could explain our data are not available at this time.

Approximate analytic expressions for determining the transmission of neutron benders which take into account reflectivity losses using the mean number of reflections agree well with computer simulation results which track the neutron trajectories directly, provided that the reflectivity is high. The exact calculation which can be performed using exponential integral functions for any value of the reflectivity is presented. Ray-tracing techniques for determining the transmission and number of reflections for non-perfect reflectivity can therefore be replaced by direct calculation.

Quasielastic gamma‐ray scattering of 46.5‐keV Mossbauer photons by polydimethylsiloxane has been studied at room temperature as a function of dilution in benzene. The high energy resolution of this novel technique allowed the separation of the scattering signal into a narrow component associated with stiff motions along the polymer chain backbone and a quasielastic component associated with softer side group motions. The narrow component disappears upon dilution in benzene while the intensity of the quasielastic component grows proportionately. This result is interpreted as a softening of the backbone normal modes upon dilution.

Most hemangiopericytomas (HPC) are located in the musculoskeletal system and the skin, while the location in the central nervous system (CNS) is rare. The latter represents 2 to 4% in large series of meningeal tumors, thus accounting for less than 1% of all CNS tumors. In the central nervous system, tumors with a hemangiopericytomatous histolopathological pattern can be either hemangiopericytomas or solitary fibrous tumors. CNS-HPCs have a relentless tendency for local recurrence and metastases outside the CNS. Metastasis can also appear many years after adequate treatment of the primary tumor. We present a pathological study of eight patients with CNS-HPC and compare our results with corresponding published data. The CNS-HPC group consisted of three males and five females with a mean age of 36.75 years. The tumors were supratentorial in four cases, infratentorial in two cases, tentorial in one case and located in the spinal cord in the last one. Histologically, CNS-HPCs were similar to their soft tissue counterparts. One case demonstrated increased cellularity, marked nuclear hyperchromasia and marked cellular pleomorphism with infiltration of the cerebellum. All patients underwent surgery with gross-total resection in all cases. No patients received postoperative radiation therapy. Only four patients recurred locally after six, seven and eight months, and five years. Our study presents the pathological features of CNS-HPC as a distinct entity from both meningioma and solitary fibrous tumors. A comparative review of literature with our results is discussed.

Cerebellar liponeurocytoma has recently been recognised by the 2000 World Health Organisation classification of tumours of the central nervous system as a distinct clinicopathologic entity. To our knowledge, 18 cases have been reported so far, under different names, such as "lipomatous medulloblastoma, lipidized medulloblastoma, neurolipocytoma, medullocytoma and lipomatous glioneurocytoma". The new classification included cerebellar liponeurocytoma in the category of glioneuronal tumours grade I or II because of its favourable clinical behaviour. The origin and nature of the lipomatous component have been matter of debate and make this tumour entity puzzling. We describe a new case of liponeurocytoma removed from the left cerebellar hemisphere of a 38-year-old-woman. The patient showed unspecific signs of intracranial hypertension and symptoms suggesting a posterior fossa lesion.

Using small-angle neutron scattering (SANS), we have investigated the transient alignment and relaxation under Couette shear of viscoelastic aqueous micellar solutions of cetyltrimethylarmmonium 3,5-dichlorobenzoate (CTA3,5C1) and CTA3,5C1/CTAB mixtures at concentrations well above ф* (but below 1.0 wt. %). Time constants of the order of ten's of minutes are reported for alignment and relaxation, orders of magnitude slower than any previously observed in similar micellar systems. The collective properties of the network of entangled, threadlike micelles, rather than the individual micellar segments, dominate the alignment and relaxation behavior. At low micellar surface charge density (σ) (e.g., in pure CTA3,5C1), the first observation of alignment proceeding in two stages has been made. Increasing a decreases by an order of magnitude the shear rate required to reach full alignment and provides a comparable decrease in the rate constant for relaxation after cessation of shear.

A recently developed M\"ossbauer instrument has been used to study the liquid dynamics of pentadecane at various temperatures and scattering angles. Widths of the quasielastic signal extracted from the data ranged between 16 GHz (at 12 \ifmmode^\circ\else\textdegree\fi{}C) and 48 GHz (at 74 \ifmmode^\circ\else\textdegree\fi{}C) at a scattering vector of 1.15 A${\mathrm{\r{}}}^{\mathrm{\ensuremath{-}}1}$. Similar measurements at five different scattering angles (at 12 \ifmmode^\circ\else\textdegree\fi{}C) were also taken to investigate the Q dependence between 0.82 and 1.56 A${\mathrm{\r{}}}^{\mathrm{\ensuremath{-}}1}$. The results obtained are in good agreement with classical theory for coherent scattering from liquids.

There is previous evidence that random copolymers of bisphenol A carbonate (BPAC) and dimethylsiloxane (DMS) form microdomain morphology. Small-angle neutron scattering (SANS) is used to investigate this system, which shows a broad-peak spectrum. The origin of this peak is due to interference scattering between the BPAC-rich microdomain and the DMS-rich interdomain regions. SANS measurements taken from such a random copolymer (50%/50% mixture) under uniaxial external stretch show that the glassy microdomains do not follow the external drawing whereas the rubbery interdomain regions do. Two data analysis methods are used: one based on nonlinear least-squares fits of the raw data to a model consisting of two confocal ellipsoids representing the deformed microdomain morphology and the other on a two-di- mensional Fourier transform of SANS data to obtain an anisotropic pair correlation function.

We use Zimm's single-contact approximation to investigate the concentration dependence of the first cumulant for partially labeled chains in dilute solutions. This approximation allows us to express interchain properties (such as the interference part of the generalized mobility) in terms of static structure factors, which are then modeled using a Gaussian chain model. We present numerical results for three specific labeling sequences.

WANS experiments were performed in order to investigate the liquid state of atactic polystyrene. It was found that PS undergoes both a reversible and an irreversible structural change at a temperature which corresponds to T ll the liquid-liquid transition. These results plus earlier results on birefringence are interpreted in terms of a structural model presented by Mitchell and Windle.