Chondrogenic potential of adipose tissue-derived stromal cells in vitro and in vivo.

Articular cartilage exhibits little intrinsic repair capacity, and new tissue engineering approaches are being developed to promote cartilage regeneration using cellular therapies. The goal of this study was to examine the chondrogenic potential of adipose tissue-derived stromal cells. Stromal cells were isolated from human subcutaneous adipose tissue obtained by liposuction and were expanded and grown in vitro with or without chondrogenic media in alginate culture. Adipose-derived stromal cells abundantly synthesized cartilage matrix molecules including collagen type II, VI, and chondroitin 4-sulfate. Alginate cell constructs grown in chondrogenic media for 2 weeks in vitro were then implanted subcutaneously in nude mice for 4 and 12 weeks. Immunohistochemical analysis of these samples showed significant production of cartilage matrix molecules. These findings document the ability of adipose tissue-derived stromal cells to produce characteristic cartilage matrix molecules in both in vitro and in vivo models, and suggest the potential of these cells in cartilage tissue engineering.     

Annexin A2 is a C-terminal PCSK9-binding protein that regulates endogenous low density lipoprotein receptor levels

The proprotein convertase subtilisin/kexin-type 9 (PCSK9), which promotes degradation of the hepatic low density lipoprotein receptor (LDLR), is now recognized as a major player in plasma cholesterol metabolism. Several gain-of-function mutations in PCSK9 cause hypercholesterolemia and premature atherosclerosis, and thus, inhibition of PCSK9-induced degradation of the LDLR may be used to treat this deadly disease. Herein, we discovered an endogenous PCSK9 binding partner by Far Western blotting, co-immunoprecipitation, and pull-down assays. Following two-dimensional gel electrophoresis and mass spectrometry analysis, we demonstrated that PCSK9 binds to a approximately 33-kDa protein identified as annexin A2 (AnxA2) but not to the closely related annexin A1. Furthermore, our functional LDLR assays and small hairpin RNA studies show that AnxA2 and the AnxA2.p11 complex could prevent PCSK9-directed LDLR degradation in HuH7, HepG2, and Chinese hamster ovary cells. Immunocytochemistry revealed that PCSK9 and AnxA2 co-localize at the cell surface, indicating a possible competition with the LDLR. Structure-function analyses demonstrated that the C-terminal cysteine-histidine-rich domain of PCSK9 interacts specifically with the N-terminal repeat R1 of AnxA2. Mutational analysis of this 70-amino acid-long repeat indicated that the RRTKK81 sequence of AnxA2 is implicated in this binding because its mutation to AATAA81 prevents its interaction with PCSK9. To our knowledge, this work constitutes the first to show that PCSK9 activity on LDLR can be regulated by an endogenous inhibitor. The identification of the minimal inhibitory sequence of AnxA2 should pave the way toward the development of PCSK9 inhibitory lead molecules for the treatment of hypercholesterolemia.     

Beer from the early dynasties (3500–3400 cal B.C.) of Upper Egypt,detected by archaeochemical methods

Physical and chemical analyses of beer residues recovered from a vat site at Hierakonpolis (Upper Egypt) were carried out. Radiocarbon dates of the residues suggest a dating of 3500–3400 cal B.C. and are believed to represent the oldest known beer in the world. Macroscopic and microscopic examinations of the residues revealed the presence of intact remains of grains and spikelets of wheat and barley, as well as fragments of dates and grape pips. Chemical analyses included percentages of sample ingredients, pH and total soluble ions, quantitative determinations of sugars, carboxylic acids and free amino acids. A total of 25 compounds were identified, which are components of fermentation processes that are believed to have formed in connection with the preparation of what is called Nekhen-Hoffman beer.     

Recessive Mutations in COL25A1 Are a Cause of Congenital Cranial Dysinnervation Disorder

Abnormal ocular motility is a common clinical feature in congenital cranial dysinnervation disorder (CCDD). To date, eight genes related to neuronal development have been associated with different CCDD phenotypes. By using linkage analysis, candidate gene screening, and exome sequencing, we identified three mutations in collagen, type XXV, alpha 1 (COL25A1) in individuals with autosomal-recessive inheritance of CCDD ophthalmic phenotypes. These mutations affected either stability or levels of the protein. We further detected altered levels of sAPP (neuronal protein involved in axon guidance and synaptogenesis) and TUBB3 (encoded by TUBB3, which is mutated in CFEOM3) as a result of null mutations in COL25A1. Our data suggest that lack of COL25A1 might interfere with molecular pathways involved in oculomotor neuron development, leading to CCDD phenotypes.     

Scanning and transmission electron microscopy of the female reproductive system of Schistosoma margrebowiei Le Roux, 1933

Transmission electron microscopy shows that the uterus of female Schistosoma margrebowiei possesses the same ultrastructure as that of the tegument but lacks spines and sense organs. It does not possess secretory cells and opens at the gonopore which by scanning electron microscopy was seen to be composed of numerous leaf-like protrusions. The morphology of the ovary is comparable with that of other Digenea. Immature and mature ova possess cortically arranged granules and occur within the posterior zone of the ovary. Cilia and lamellae line the luminal surface of the oviduct and ootype, the lamellae running unidirectionally along the duct. Only a single type of secretory cell is seen within Mehlis' gland and this produces dense bodies which are associated with Goldi bodies. Narrow cytoplasmic channels supported by microtubules deliver these secretory bodies to the ootype. The vitelline duct is lined with cilia and lamellae and the vitelline gland contains four types of cells, S1, S2, S3 and S4. Calcareous corpuscles are found within mature S4 cells.     

Factors affecting spore germination in Aspergillus niger

Temperature markedly affected germination and germ tube length of A. niger. More than 90% of the spores were germinated in the range 30°–34 °C and formed maximum length of germ tubes. At temperatures from 38° to 43 °C, the proportion of the spores that germinated as well as the germ tube length were both gradually decreased. However, at 47°C germ tube formation was completely inhibited up to 15 hrs. after inoculation.High relative humidity was found necessary for the spore germination of A. niger. Germination failed to occur at 76% relative humidity. At 78 and 81% relative humidity germination was detected 15 hrs. after inoculation while at the higher humidities germination was started after 6 hrs. only.Conidiospores of A. niger were very sensitive to changes in the hydrogen ion concentration, pH. Complete inhibition of germination was found at pH less than 3.5. The germination and the length of the formed germ tubes increased with pH to reach their maximum rates at pH 4.5.     

Dapsone-Loaded Invasomes as a Potential Treatment of Acne: Preparation,Characterization, and <Emphasis Type="Italic">In Vivo</Emphasis> Skin Deposition Assay

Dapsone (DPS) is a unique sulfone with antibiotic and anti-inflammatory activity. Owing to its dual action, DPS has a great potential to treat acne. Topical DPS application is expected to be effective in treatment of mild to moderate acne conditions. Invasomes are novel vesicles composed of phosphatidylcholine, ethanol, and one or mixture of terpenes of enhanced percutaneous permeation. In this study, DPS-loaded invasomes were prepared using the thin film hydration technique. The effect of different terpenes (Limonene, Cineole, Fenchone, and Citral) in different concentrations on the properties of the prepared DPS-loaded invasomes was investigated using a full factorial experimental design, namely, the particle size, drug entrapment, and release efficiency. The optimized formulation was selected for morphological evaluation which showed spherical shaped vesicles. Further solid-state characterization using differential scanning calorimetry and X-ray diffractometry revealed that the drug was dispersed in an amorphous state within the prepared invasomes. Finally, the ability of the prepared DPS-loaded invasomes to deliver DPS through the skin was investigated in vivo using wistar rats. The maximum in vivo skin deposition amount of DPS was found to be 4.11 mcg/cm² for invasomes versus 1.71 mcg/cm² for the drug alcoholic solution, representing about 2.5-fold higher for the invasomes compared to the drug solution. The AUC0–10 calculated for DPS-loaded invasomes was nearly 2-fold greater than that of DPS solution (14.54 and 8.01 mcg.h/cm² for the optimized invasomes and DPS solution, respectively). These results reveal that the skin retention of DPS can be enhanced using invasomes.     

Addition of tryptophan methyl-ester on [60]fullerene: theoretical investigation of the mechanisms of azomethine ylides and fulleropyrrolidine formation

In this paper, we perform the synthesization of carbon nanoparticles for active principle vectorization, with the suggestion of a reaction mechanism of tryptophan methyl ester addition on [60]fullerene. Firstly, we studied the effect of tryptophan form on its addition reaction on [60]fullerene. So, in order to determine the preferred environment that makes this reaction the most favorable, we considered all tryptophan possible forms in our investigation: the molecular, the zwitterionic, and the dibasic forms. Secondly, we investigate the proposed reaction mechanism of tryptophan methyl ester addition on [60]fullerene using theoretical thermodynamic calculation. Our hypothesis suggests the formation of azomethine ylide molecule in a first step followed by its addition on [60]fullerene in the second step by the photo-addition reaction involving the oxygen in its singlet state. The stability of each reactive intermediate involved in this mechanism is verified thermodynamically. The 12 most stable conformations of azomethine ylide were observed through potential energy surface analysis. They were obtained by a relaxed scan of the four dihedral angles. The calculations were conducted on the optimized geometry of fulleropyrrolidine mono-adduct and the bulk values of its thermodynamic constants were also determined. Infrared spectra observed in 100–4000 cm^?1 region confirmed our hypothesis suggesting the first step of azomethine ylide formation followed by the second step of azomethine ylide addition on [60]fullerene by ν(C_aliphatic-C-N), ν(C_aromatic-C-N) and ^δ(N-H) coupled with ν(C-N) absorption bond.

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Graphical abstract Optimized geometry of the Fulleropyrrolidine monoaduct molecule.