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he treatment of complex wounds is difficult and not always effective. Various treatment options are used with varying degrees of success. Negative pressure wound therapy (NPWT) is a cost-efficient and effective way to help treat these wounds. The use of a vacuum device applies the negative pressure to the site of the wound and promotes waste removal and increases circulation and tissue formation. While various NPWT systems are currently on the market, we utilised the ConvaTec Engenex® system with Bio-Dome™ technology; however, our case study is not intended to advocate the specific use of this system, but instead focuses on the use of NPWT as a viable option for wound healing. Each of the following case study patients presented with difficult-to-heal wounds that failed traditional therapeutic approaches. Through the use of NPWT, our patients saw major wound size reductions. Each patient exhibited at least a 94% reduction in wound area, wound volume or both. [ABSTRACT FROM AUTHOR]

Necrobiosis lipoidica is a rare skin disease characterised by large, well-demarcated, symmetrical plaques with overlying telangiectasias and atrophic, fibrotic features. The disease is associated with diabetes mellitus (1 in 300 cases), but can also be linked to other diseases such as rheumatoid arthritis. Women are three times more likely to develop necrobiosis lipoidica compared to men. Ulcerations are the most serious type of complications in necrobiosis lipoidica, and they occur most frequently on the legs of patients. However, the aetiology of necrobiosis lipoidica still remains unclear. Although many studies have been conducted in order to determine necrobiosis lipoidica's pathophysiology, a clear and definite path to disease has not been recorded. In this case study, a patient with necrobiosis lipoidica that had been refractory to conventional therapy received treatment with Apligraf® bioengineered wound dressings. Apligraf was shown to be effective in managing the patient's multiple hard-to-heal wounds. It was more successful than previous therapies in achieving granulation tissue formation and wound volume reduction, in addition to being a more rapid form of treatment. [ABSTRACT FROM AUTHOR]

Photoactivatable fluorescent proteins represent an innovative tool for the direct observation of time dependent macromolecular events in living systems. The possibility of switching on a selected and confined subset of the expressed target proteins allows to follow biological processes reaching high signal to noise ratios. In particular, use of non-linear interactions to bring the molecules in the activated fluorescent form make it possible to extend the advantages of photoactivation to events that requires 3D spatial localization. In this work, we show the possibility to realize confined activated volumes in living cells, by employing photoactivatable green fluorescent protein (paGFP) in two-photon microscopy. The analysis of the kinetics of two-photon paGFP activation in dependence of the wavelength, the laser intensity and the exposure time is provided. This study allowed to assess the optimal conditions to induce photoactivation in living samples and to track the behaviour of tagged histone H2B during cellular division. Furthermore we investigate paGFP photoactivation under evanescent wave illumination. Total internal reflection set-up has been used to selectively activate subresolved distribution of proteins localized in the basal membrane surroundings. These two photoactivation methods provide a suitable tool for many biological applications, combining subresolved surface and in-depth three-dimensionally confined investigations. [ABSTRACT FROM AUTHOR]

Photoactivatable green fluorescent protein (paGFP) exhibits peculiar photo-physical properties making it an invaluable tool for protein/cell tracking in living cells/organisms. paGFP is normally excited in the violet range (405 nm), with an emission peak centred at 520 nm. Absorption cross-section at 488 nm is low in the not-activated form. However, when irradiated with high-energy fluxes at 405 nm, the protein shows a dramatic change in its absorption spectra becoming efficiently excitable at 488 nm. Confocal microscopes allow to control activation in the focal plane. Unfortunately, irradiation extends to the entire illumination volume, making impracticable to limit the process in the 3D (three-dimensional) space. In order to confine the process, we used two advanced intrinsically 3D confined optical methods, namely: total internal reflection fluorescence (TIRF) and two-photon excitation fluorescence (2PE) microscopy. TIRF allows for spatially selected excitation of fluorescent molecules within a thin region at interfaces, i.e. cellular membranes. Optimization of the TIRF optical set-up allowed us to demonstrate photoactivation of paGFP fused to different membrane localizing proteins. Exploitation of the penetration depth showed that activation is efficiently 3D confined even if limited at the interface. 2PE microscopy overcomes both the extended excitation volume of the confocal case and the TIRF constraint of operating at interfaces, providing optical confinement at any focal plane in the specimen within subfemtoliter volumes. The presented results emphasize how photoactivation by non-linear excitation can provide a tool to increase contrast in widefield and confocal cellular imaging. [ABSTRACT FROM AUTHOR]

Thiocoraline, a new anticancer agent derived from the marine actinomycete Micromonospora marina, was found to induce profound perturbations of the cell cycle. On both LoVo and SW620 human colon cancer cell lines, thiocoraline caused an arrest in G1 phase of the cell cycle and a decrease in the rate of S phase progression towards G2/M phases, as assessed by using bromodeoxyuridine/DNA biparametric flow cytometric analysis. Thiocoraline does not inhibit DNA-topoisomerase II enzymes in vitro, nor does it induce DNA breakage in cells exposed to effective drug concentrations. The cell cycle effects observed after exposure to thiocoraline appear related to the inhibition of DNA replication. By using a primer extension assay it was found that thiocoraline inhibited DNA elongation by DNA polymerase a at concentrations that inhibited cell cycle progression and clonogenicity. These studies indicate that the new anticancer drug thiocoraline probably acts by inhibiting DNA polymerasea activity. [ABSTRACT FROM AUTHOR]

Summary Isohomohalichondrin B (IHB), a novel marine compound with anti-tumoral activity, extracted from the Lissodendorix sponge, inhibits GTP binding to tubulin, preventing microtubule assembly. Cell cycle perturbations and apoptosis induced by IHB were investigated on selected human cancer cell lines by using flow cytometric and biochemical techniques. Monoparameter flow cytometric analysis showed that 1 (h IHB exposure caused a delayed progression through S-phase, a dramatic block in G)2(M phase of the cell cycle and the appearance of) tetraploid cell population in LoVo, LoVo/DX, MOLT-4 and K562 cells. At 24 (h after IHB exposure, the majority of cells blocked in G)2(M were in) prophase as assessed by morphological analysis and by the fact that they expressed high levels of cyclin A/cdc2 and cyclin B1/cdc2. At 48 h, all cells were tetraploid as assessed by biparameter cyclin A/DNA and cyclin B1/DNA content analysis. Apoptotic death was detected in both leukaemic MOLT-4 and K562 cells, which express wild-type and mutated p53 respectively, when the cells were blocked in mitotic prophase. In conclusion, IHB is a novel potent anti-tumour drug that causes delayed S-phase progression, mitotic block, tetraploidy and apoptosis in cancer cell lines. [ABSTRACT FROM AUTHOR]

he treatment of complex wounds is difficult and not always effective. Various treatment options are used with varying degrees of success. Negative pressure wound therapy (NPWT) is a cost-efficient and effective way to help treat these wounds. The use of a vacuum device applies the negative pressure to the site of the wound and promotes waste removal and increases circulation and tissue formation. While various NPWT systems are currently on the market, we utilised the ConvaTec Engenex® system with Bio-Dome™ technology; however, our case study is not intended to advocate the specific use of this system, but instead focuses on the use of NPWT as a viable option for wound healing. Each of the following case study patients presented with difficult-to-heal wounds that failed traditional therapeutic approaches. Through the use of NPWT, our patients saw major wound size reductions. Each patient exhibited at least a 94% reduction in wound area, wound volume or both. [ABSTRACT FROM AUTHOR]

Necrobiosis lipoidica is a rare skin disease characterised by large, well-demarcated, symmetrical plaques with overlying telangiectasias and atrophic, fibrotic features. The disease is associated with diabetes mellitus (1 in 300 cases), but can also be linked to other diseases such as rheumatoid arthritis. Women are three times more likely to develop necrobiosis lipoidica compared to men. Ulcerations are the most serious type of complications in necrobiosis lipoidica, and they occur most frequently on the legs of patients. However, the aetiology of necrobiosis lipoidica still remains unclear. Although many studies have been conducted in order to determine necrobiosis lipoidica's pathophysiology, a clear and definite path to disease has not been recorded. In this case study, a patient with necrobiosis lipoidica that had been refractory to conventional therapy received treatment with Apligrafî bioengineered wound dressings. Apligraf was shown to be effective in managing the patient's multiple hard-to-heal wounds. It was more successful than previous therapies in achieving granulation tissue formation and wound volume reduction, in addition to being a more rapid form of treatment. [ABSTRACT FROM AUTHOR]