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Morphological, ultrastructural, and molecular-sequence data were used to assess the phylogenetic position of a tetraflagellate green alga isolated from soil samples of a saline dry basin near F'derick, Mauritania. This alga can grow as individual cells or form non-coenobial colonies of up to 12 individuals. It has a parietal chloroplast with an embedded pyrenoid covered by a starch sheath and traversed by single parallel thylakoids, and an eyespot located in a parietal position opposite to the flagellar insertion. Lipid vacuoles are present in the cytoplasm. Microspectroscopy indicated the presence of chlorophylls a and b, with lutein as the major carotenoid in the chloroplast, while the eyespot spectrum has a shape typical of green-algal eyespots. The cell has four flagella, two of them long and two considerably shorter. Sequence data from the 18S r RNA gene and ITS2 were obtained and compared with published sequences for green algae. Results from morphological and ultrastructural examinations and sequence analysis support the placement of this alga in the Chlorophyceae, as Tetraflagellochloris mauritanica L. Barsanti et A. Barsanti, gen. et sp. nov. [ABSTRACT FROM AUTHOR]

Autism spectrum disorders (ASDs) are a complex group of neurodevelopment disorders steadily rising in frequency and treatment refractory, where the search for biological markers is of paramount importance. Although red blood cells (RBCs) membrane lipidomics and rheological variables have been reported to be altered, with some suggestions indicating an increased lipid peroxidation in the erythrocyte membrane, to date no information exists on how the oxidative membrane damage may affect cytoskeletal membrane proteins and, ultimately, RBCs shape in autism. Here, we investigated RBC morphology by scanning electron microscopy in patients with classical autism, that is, the predominant ASDs phenotype (age range: 6-26 years), nonautistic neurodevelopmental disorders (i.e., "positive controls"), and healthy controls (i.e., "negative controls"). A high percentage of altered RBCs shapes, predominantly elliptocytes, was observed in autistic patients, but not in both control groups. The RBCs altered morphology in autistic subjects was related to increased erythrocyte membrane F2-isoprostanes and 4-hydroxynonenal protein adducts. In addition, an oxidative damage of the erythrocyte membrane β-actin protein was evidenced. Therefore, the combination of erythrocyte shape abnormalities, erythrocyte membrane oxidative damage, and β-actin alterations constitutes a previously unrecognized triad in classical autism and provides new biological markers in the diagnostic workup of ASDs. [ABSTRACT FROM AUTHOR]

Poly- BF3a, a new hydrophobic polymer obtained by spontaneous polymerization of 1-methylene-3-phenyl-1 H-indene, was found to give nanoparticles characterized by favorable shape and dimensions. Poly- BF3a nanoparticles were loaded with CR3124, a potent 5HT3 antagonist, as a drug model by desolvation methods either in the absence or in the presence of polyethylene glycol (PEG1000) as a wetting agent. The SEM studies showed that the introduction of CR3124 into the preparation led to a variable degree of aggregation–cementation, which afforded a sort of nanocomposite material. In the absence of PEG1000, the drug molecule was found to stay in the amorphous state (DSC studies) when its percentage is not higher than 10% by weight. In vitro release experiments showed that the formation and stability of the dispersion as well as the drug release were remarkably affected by the presence of PEG1000, demonstrating its beneficial effect to the nanoparticle morphology and disaggregation. [ABSTRACT FROM AUTHOR]

Marine diatoms have been identified among the most abundant taxa of microorganisms associated with plastic waste collected at sea. However, the impact of nano-sized plastic fragments (nanoplastics) at single cell and population level is almost unknown. We exposed the marine diatom Skeletonema marinoi to model polystyrene nanoparticles with carboxylic acid groups (PS–COOH NPs, 90 nm) for 15 days (1, 10, 50 μg/mL). Growth, reactive oxygen species (ROS) production, and nano-bio-interactions were investigated. No effect on diatom growth was observed, however Dynamic light scattering (DLS) demonstrated the formation of large PS aggregates which were localized at the diatoms' fultoportula process (FPP), as shown by TEM images. Increase production of ROS and reduction in chain length were also observed upon PS NPs exposure (p < 0.005). The observed PS-diatom interaction could have serious consequences on diatoms ecological role on the biogeochemical cycle of carbon, by impairing the formation of fast-sinking aggregates responsible for atmospheric carbon fixation and sequestration in the ocean sea floor. S. marinoi exposure to PS NPs caused an increase of intracellular and extracellular oxidative stress, the reduction of diatom's chain length and the adhesion of PS NPs onto the algal surface. Image 1 • PN NPs do not affect S. marinoi growth rate. • Fifteen days of exposure to PS NPs affect diatoms at cell and colony level. • PS NPs exposure resulted in a reduction of diatom's colony chain length. • PS NPs aggregates localized at diatom's fultoportula process. • PS NPs causes an increase in intracellular and extracellular ROS. [ABSTRACT FROM AUTHOR]

A new polymer brush was synthesized by spontaneous polymerization of benzofulvene macromonomer 6-MOEG-9-T-BF3k bearing a nona(ethylene glycol) side chain linked to the 3-phenylindene scaffold by means of a triazole heterocycle. The polymer structure was studied by SEC-MALS, NMR spectroscopy, and MALDI-TOF MS techniques, and the results supported the role of oligomeric initiatory species in the spontaneous polymerization of polybenzofulvene derivatives. The aggregation features of high molecular weight poly-6-MOEG-9-T-BF3k-FE were investigated by pyrene fluorescence analysis, dynamic light scattering studies, and transmission electron microscopy, which suggested a tendency towards the formation of spherical objects showing dimensions in the range of 20–200 nm. Moreover, poly-6-MOEG-9-T-BF3k-FE showed an interesting cytocompatibility in the whole concentration range tested that, besides its aggregation features, makes this polybenzofulvene brush a good polymer candidate for nanoencapsulation and delivery of drug molecules. Finally, the photo-physical features of poly-6-MOEG-9-T-BF3k-FE could allow the biodistribution of the resulting drug delivery systems to be monitored by fluorescence microscopy techniques. [ABSTRACT FROM AUTHOR]

The physicochemical and biopharmaceutical properties, such as pKa, crystal habit, water solubility, logD, molecular structure and dynamics, and membrane permeability of CR3124 (endo-2-(8-methyl-8-azabicyclo[3.2.1]oct-3-yl)-2,3-dihydro-1H-benz[e]isoindol-1-one, a novel potent 5-HT3 receptor antagonist) have been studied in order to obtain preformulation information. The study showed that CR3124 is a very rigid molecule in which conformational freedom due to the presence of a rotatable bond is restricted by the interaction between an activated hydrogen and the amide oxygen and the conformation of the tropane piperidine ring is regulated by the environment in such a manner as to optimize the intermolecular interactions with the solvent. This chameleon behavior appears to be capable of explaining the biopharmaceutical properties showed by CR3124, such as low wettability, relatively good solubility, and very high membrane permeability. Copyright © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95:2706–2721, 2006 [ABSTRACT FROM AUTHOR]

Summary: The winding process leading to the formation of rolled-up spermatozoa in Collembola is described. It is a phenomenon common to all collembolan species examined so far and it starts with the organization of a cytoplasmic flattened evagination beneath the head of the elongated spermatid, which gives rise to an extracellular cavity. Within this cavity secretory material produced by the epithelial cells of testes is progressively stored. The spermatozoon, whose cytoplasm is reduced to a thin layer, enrolls around this material. The final appearance is that of a spheroidal or lenticular structure containing dense material in the central extracellular cavity; this cavity is surrounded by the flattened sperm in whose cytoplasm the sperm components forms several spires. The material into the extracellular cavity becomes progressively denser and has a different appearance in the species examined. [Copyright &y& Elsevier]

Pseudomonas aeruginosa , a pathogen capable of causing diseases ranging from mild to life-threatening, has a large arsenal of virulence factors. Notably, extracellular vesicles have emerged as significant players in the pathogenesis of this organism. However, the full range of their functions is still being studied, and difficulties related to vesicle purification (long protocols, low yields, and specialized instruments) have become a major obstacle for their characterization. In this context, the utility of rapid new methods of vesicle isolation from clinical strains is still unknown. Here, we analyze the utility of the ExoBacteria OMV isolation kit for a collection of clinical strains of P. aeruginosa . We first phenotypically characterized 15 P . aeruginosa strains to ensure that our samples were heterogeneous. We then determined the best conditions for purifying vesicles from P. aeruginosa PAO1 reference strain by the rapid method and used them to isolate vesicles from clinical strains. Our results indicated that M9 minimal medium is the best for obtaining high purity with the rapid isolation kit. Although we were able to isolate vesicles from at least four strains, the low yield and the large number of strains with unpurifiable vesicles showed that the kit was not practical or convenient for clinical strains. Our findings suggest that although fast procedures for vesicle purification can be of great utility for Escherichia coli , the more complex phenotypes of clinical isolates of P. aeruginosa are a challenge for these protocols and new alternatives/optimizations need to be developed.IMPORTANCE Pseudomonas aeruginosa is recognized as an opportunistic pathogen in humans and animals. It can effectively colonize various environments thanks to a large set of virulence factors that include extracellular vesicles. Different methods were recently developed to reduce the time and effort associated with vesicle purification. However, the utility of rapid vesicle isolation methods for clinical strains of P. aeruginosa (which are recognized as being highly diverse) is not yet known. In this context, we analyzed the utility of the ExoBacteria OMV Isolation kit for vesicle purification in P. aeruginosa clinical strains. Our findings showed that the kit does not seem to be convenient for research on clinical strains due to low vesicle recovery. Our results underscore the importance of developing new rapid vesicle purification protocols/techniques for specific clinical phenotypes., Competing Interests: The authors declare no conflict of interest.

HBDI-like chromophores represent a novel set of biomimetic switches mimicking the fluorophore of the green fluorescent protein that are currently studied with the hope to expand the molecular switch/motor toolbox. However, until now members capable of absorbing visible light in their neutral (i. e. non-anionic) form have not been reported. In this contribution we report the preparation of an HBDI-like chromophore based on a 3-phenylbenzofulvene scaffold capable of absorbing blue light and photoisomerizing on the picosecond timescale. More specifically, we show that double-bond photoisomerization occurs in both the E-to-Z and Z-to-E directions and that these can be controlled by irradiating with blue and UV light, respectively. Finally, as a preliminary applicative result, we report the incorporation of the chromophore in an amphiphilic molecule and demonstrate the formation of a visible-light-sensitive nanoaggregated state in water., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Two novel benzofulvene monomers bearing propargyl or allyl groups have been synthesized by means of readily accessible reactions, and were found to polymerize spontaneously by solvent removal, in the apparent absence of catalysts or initiators, to give the corresponding polybenzofulvene derivatives bearing clickable propargyl or allyl moieties. The clickable propargyl and allyl groups were exploited in appropriate click reactions to develop a powerful and versatile "grafting onto" synthetic methodology for obtaining tailored polymer brushes., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Cilia and flagella play very important roles in eukaryotic cells, ranging from cell motility to chemo- and mechanosensation with active involvement in embryonic development and control of cell division. Cilia and flagella are highly dynamic organelles undergoing constant turnover at their tip, where multiprotein precursors synthesized in the cell cytoplasm are assembled, turnover products are released and carried back for recycling. Such bidirectional trafficking is maintained by an ATP-dependent active transport that is carried out by intraflagellar transport (IFT) particles. Despite our knowledge of the cell biology, the genomic, and the biochemistry of IFT, high-resolution 3D models for IFT are still missing. To date, the only information on the 3D structure of IFT come from our analysis of full-length flagella from the biflagellate green alga Chlamydomonas reinhardtii: the model organism where IFT was discovered and first characterized. In this chapter, we describe and discuss the strategy we implemented to produce the first 3D models of in situ IFT trains in flat-embedded flagella. We provide detailed information about the acquisition of tomographic images, the simultaneous alignment of the double-tilt tomographic series, and the analysis of the tomograms by subtomogram averaging for the generation of detailed 3D models of IFT particles., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The physicochemical and biopharmaceutical properties, such as pK(a), crystal habit, water solubility, logD, molecular structure and dynamics, and membrane permeability of CR3124 (endo-2-(8-methyl-8-azabicyclo[3.2.1]oct-3-yl)-2,3-dihydro-1H-benz[e]isoindol-1-one, a novel potent 5-HT(3) receptor antagonist) have been studied in order to obtain preformulation information. The study showed that CR3124 is a very rigid molecule in which conformational freedom due to the presence of a rotatable bond is restricted by the interaction between an activated hydrogen and the amide oxygen and the conformation of the tropane piperidine ring is regulated by the environment in such a manner as to optimize the intermolecular interactions with the solvent. This chameleon behavior appears to be capable of explaining the biopharmaceutical properties showed by CR3124, such as low wettability, relatively good solubility, and very high membrane permeability., ((c) 2006 Wiley-Liss, Inc. and the American Pharmacists Association)

Placental viviparity is a reproductive strategy usually attributed to mammals. However, it is also present in other vertebrate species, e.g. in Squamate reptiles. Although the immunological mechanisms that allow the survival of the semi-allogenic embryo in maternal tissues are still largely unknown, cytokines seem to play an important role in mammalian reproduction. Previous studies in our laboratory showed that interleukin-1 (IL-1), a cytokine associated with implantation in mice, is also expressed at the materno-fetal interface of placental viviparous Squamates. In this study, we used the model of Lacerta vivipara, which exhibits reproductive bimodality, that is, the coexistence of oviparous and viviparous populations. By means of immunohistochemistry and anti-human antibodies, we showed that uterine tissues of L. vivipara (seven oviparous and six viviparous animals) expressed the two IL-1 isoforms, IL-1alpha and IL-1beta, and the type I IL-1 receptor (IL-1R tI) both at the pre-ovulatory stage and during gestation, with no significant difference between oviparous and viviparous females. In L. vivipara, as in most oviparous Squamates, an important phase of embryonic development takes place in the mother's oviduct, before egg-laying. Moreover, although thinner than in oviparous females, an eggshell membrane persists throughout gestation in viviparous females also, which develop a very simple type of placenta. The data suggest that immunological mechanisms that allow the survival of the semi-allogenic embryo in maternal tissues are independent of the timing or intimacy of contact between maternal and fetal tissues.