A Bio-Conjugated Fullerene as a Subcellular-Targeted and Multifaceted Phototheranostic Agent

Fullerenes are candidates for theranostic applications because of their high photodynamic activity and intrinsic multimodal imaging contrast. However, fullerenes suffer from low solubility in aqueous media, poor biocompatibility, cell toxicity, and a tendency to aggregate. C₇₀@lysozyme is introduced herein as a novel bioconjugate that is harmless to a cellular environment, yet is also photoactive and has excellent optical and optoacoustic contrast for tracking cellular uptake and intracellular localization. The formation, water-solubility, photoactivity, and unperturbed structure of C₇₀@lysozyme are confirmed using UV-visible and 2D ¹H, ¹⁵N NMR spectroscopy. The excellent imaging contrast of C₇₀@lysozyme in optoacoustic and third harmonic generation microscopy is exploited to monitor its uptake in HeLa cells and lysosomal trafficking. Last, the photoactivity of C₇₀@lysozyme and its ability to initiate cell death by means of singlet oxygen (¹O₂) production upon exposure to low levels of white light irradiation is demonstrated. This study introduces C₇₀@lysozyme and other fullerene-protein conjugates as potential candidates for theranostic applications.     

Maskless Preparation of Spatially-Resolved Plasmonic Nanoparticles on Polydimethylsiloxane via In Situ Fluoride-Assisted Synthesis

Here, a fluoride-assisted route for the controlled in-situ synthesis of metal nanoparticles (NPs) (i.e., AgNPs, AuNPs) on polydimethylsiloxane (PDMS) is reported. The size and coverage of the NPs on the PDMS surface are modulated with time and over space during the synthetic process, leveraging the improved yield (10×) and faster kinetics (100×) of NP formation in the presence of F⁻ ions, compared to fluoride-free approaches. This enables the maskless preparation of both linear and step gradients and patterns of NPs in 1D and 2D on the PDMS surface. As an application in flexible plasmonics/photonics, continuous and step-wise spatial modulations of the plasmonic features of PDMS slabs with 1D and 2D AgNP gradients on the surface are demonstrated. An excellent spatially resolved tuning of key optical parameters, namely, optical density from zero to 5 and extinction ratio up to 100 dB, is achieved with AgNP gradients prepared in AgF solution for 12 minutes; the performance are comparable to those of commercial dielectric/interference filters. When used as a rejection filter in optical fluorescence microscopy, the AgNP-PDMS slabs are able to reject the excitation laser at 405 nm and retain the green fluorescence of microbeads (100 µm) used as test cases.     

Synapse elimination in the central nervous system: functional significance and cellular mechanisms

Recent research into the developmental elimination of supernumerary synapses has increased understanding of this process. In this review we discuss synapse elimination both at the neuromuscular junction and in the central nervous system, considering some possible underlying mechanisms suggested by recent studies. In addition a well-described example of central nervous system synapse elimination, the climbing fiber-Purkinje cell synapse of the cerebellum, is used to explore the functional significance of synaptic regression during brain development.     

Potentiation of tumour necrosis factor-mediated cell killing by VP16 on human ovarian cancer cell lines. In vitro results and clinical implications

Synergism between recombinant human tumour necrosis factor (rHuTNF) and DNA topoisomerase II inhibitor VP16 during the killing of cells has been studied in six human ovarian cancer cell lines (A2774, A2780, SW626, IGROV-1, SKOV3, Pa1) and a cervical carcinoma cell line (Me180). Studies were performed using an assay of colony formation inhibition (drug treatment for 1 h) and a growth inhibition assay (continuous exposure for 20 h). Concomitant treatment of cells with VP16+rHuTNF enhanced cell killing in all the cell lines tested--an effect observed in both short- and long-term cytotoxicity assays. This study suggests that the activity of VP16 in ovarian cancer cell lines might be enhanced by rHuTNF in in vitro models.     

Modeling and sensitivity analysis of fire emissions in southern Africa during SAFARI 2000

This paper uses three recently generated southern African satellite burned area products for the month of September 2000 in a sensitivity study of regional biomass burning emissions for a number of trace gases and particulates. Differences in the extent and location of areas burned among products generated from Moderate Resolution Imaging Spectroradiometer (MODIS), Systeme Pour l'Observation de la Terre (SPOT-VEGETATION), and Along Track Scanning Radiometer (ATSR-2) data are significant and result in different emissions estimates for woodland and grassland land cover types. Due to the different emission profiles in woodlands and grasslands, favoring relatively more products of incomplete combustion in woodlands compared with products of complete combustion in grasslands in the late dry season, these changes are not proportional to the differences in the burned area amounts. The importance of accurate burned area information not just in terms of the total area but also in terms of its spatial distribution becomes apparent from our modeling results. This paper highlights the urgent need for satellite data producers to provide accuracy assessments associated with satellite-derived products. Preferably, these accuracy data will be spatially explicit, or defined in a way that can be applied in a spatially explicit modeling context, to enable emissions uncertainties to be defined with respect to different landscape units in support of greenhouse gas emissions reporting.     

Gamma-Ray-Induced Multi-Effect on Properties of Chalcogenide Glasses

Gamma-ray irradiations induced various alterations in sulfur- and selenium-based chalcogenide glasses. The absorbed dose was in the range of 0.01–3.6 MGy. The glasses exhibit prominent sensitivity to γ-ray irradiation, characterized by changes in some of the physical properties of the glasses, e.g., optical transmission, optical band gap, density, and thermal expansion coefficient. The effects on glass structure and microscopic morphology were also studied by Raman spectra and scanning electron microscopic observations.     

Maternal-fetal transmission of HIV

Rolipram inhibited U937 cell phosphodiesterase-4 in either the presence or absence of saturating (100 micrograms/ml) phosphatidic acid in an apparently phospholipid-independent manner, exhibiting similar kinetics (Ki values = 0.41 and 0.59 microM, respectively). At low concentrations (10 and 100 nM), however, rolipram caused a rightward shift of the phosphatidic acid concentration-response curve for phosphodiesterase-4 activation, suppressing activation by up to 70%. Maximum inhibition of phosphodiesterase-4 activation occurred at phosphatidic acid concentrations of 5-40 micrograms/ml. The results suggest that rolipram is capable of inhibiting phosphodiesterase-4 by both phospholipid-dependent and phospholipid-independent mechanisms.     

An anomalous vena cava inferior with azygos continuation: a clinical case report

We report a case of azygos continuation of inferior vena cava. The diagnosis is confirmed by C.T. scans. We also report possible diagnosis among other pathologies which substain similar radiographic pictures bat which are connected with silent clinic evolution.