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Craniosynostosis is a group of disorders of premature calvarial suture fusion. The identity of the calvarial stem cells (CSCs) that produce fusion-driving osteoblasts in craniosynostosis remains poorly understood. Here we show that both physiologic calvarial mineralization and pathologic calvarial fusion in craniosynostosis reflect the interaction of two separate stem cell lineages; a previously identified cathepsin K (CTSK) lineage CSC1(CTSK+CSC) and a separate discoidin domain-containing receptor 2 (DDR2) lineage stem cell (DDR2+CSC) that we identified in this study. Deletion of Twist1, a gene associated with craniosynostosis in humans2,3, solely in CTSK+CSCs is sufficient to drive craniosynostosis in mice, but the sites that are destined to fuse exhibit an unexpected depletion of CTSK+CSCs and a corresponding expansion of DDR2+CSCs, with DDR2+CSC expansion being a direct maladaptive response to CTSK+CSC depletion. DDR2+CSCs display full stemness features, and our results establish the presence of two distinct stem cell lineages in the sutures, with both populations contributing to physiologic calvarial mineralization. DDR2+CSCs mediate a distinct form of endochondral ossification without the typical haematopoietic marrow formation. Implantation of DDR2+CSCs into suture sites is sufficient to induce fusion, and this phenotype was prevented by co-transplantation of CTSK+CSCs. Finally, the human counterparts of DDR2+CSCs and CTSK+CSCs display conserved functional properties in xenograft assays. The interaction between these two stem cell populations provides a new biologic interface for the modulation of calvarial mineralization and suture patency.

Ribosome dysfunction is implicated in multiple abnormal developmental and disease states in humans. Heterozygous germline mutations in genes encoding ribosomal proteins are found in most individuals with Diamond-Blackfan anemia (DBA), whereas somatic mutations have been implicated in a variety of cancers and other disorders. Ribosomal protein-deficient animal models show variable phenotypes and penetrance, similar to human patients with DBA. In this study, we characterized a novel ENU mouse mutant (Skax23m1Jus) with growth and skeletal defects, cardiac malformations, and increased mortality. After genetic mapping and whole-exome sequencing, we identified an intronic Rpl5 mutation, which segregated with all affected mice. This mutation was associated with decreased ribosome generation, consistent with Rpl5 haploinsufficiency. Rpl5Skax23-Jus/+ animals had a profound delay in erythroid maturation and increased mortality at embryonic day (E) 12.5, which improved by E14.5. Surviving mutant animals had macrocytic anemia at birth, as well as evidence of ventricular septal defect (VSD). Surviving adult and aged mice exhibited no hematopoietic defect or VSD. We propose that this novel Rpl5Skax23-Jus/+ mutant mouse will be useful in studying the factors influencing the variable penetrance that is observed in DBA.

Ribosome dysfunction is implicated in multiple abnormal developmental and disease states in humans. Heterozygous germline mutations in genes encoding ribosomal proteins are found in most individuals with Diamond-Blackfan anemia (DBA), whereas somatic mutations have been implicated in a variety of cancers and other disorders. Ribosomal protein-deficient animal models show variable phenotypes and penetrance, similar to human patients with DBA. In this study, we characterized a novel ENU mouse mutant (Skax23m1Jus) with growth and skeletal defects, cardiac malformations, and increased mortality. After genetic mapping and whole-exome sequencing, we identified an intronic Rpl5mutation, which segregated with all affected mice. This mutation was associated with decreased ribosome generation, consistent with Rpl5haploinsufficiency. Rpl5Skax23-Jus/+animals had a profound delay in erythroid maturation and increased mortality at embryonic day (E) 12.5, which improved by E14.5. Surviving mutant animals had macrocytic anemia at birth, as well as evidence of ventricular septal defect (VSD). Surviving adult and aged mice exhibited no hematopoietic defect or VSD. We propose that this novel Rpl5Skax23-Jus/+mutant mouse will be useful in studying the factors influencing the variable penetrance that is observed in DBA.

Several assessment tools were recently introduced for the evaluation of the greenness of analytical methods. Each tool has advantages, disadvantages, and a unique assessment protocol. The final results obtained from each assessment tool may lead to a dissimilar conclusion about the selection of the greenest method, which makes the decision confusing as to which an assessment tool relies on. Accordingly, in this comparative case study, four greenness assessment tools—National Environmental Methods Index (NEMI), Eco-Scale Assessment (ESA), Green Analytical Procedure Index (GAPI), and Analytical GREEnness metric (AGREE)—were tested to evaluate 16 chromatographic methods described in the literature for the assessment of the commonly used antispasmodic drug Hyoscine N-butyl bromide (HNBB). The importance of applying more than one assessment tool when evaluating the greenness of analytical methods is explained in this study. Despite NEMI tool simplicity, it was the least effective in providing information about the analytical method as 14 out of 16 methods had the same NEMI pictogram. ESA and AGREE provided reliable numerical assessments that differed in their total scores whereas the total scores were out of 100 and 1 for each, respectively. AGREE has the merits over ESA with respect to automation and highlighting the weakest points in analytical techniques that need further improvements in terms of greenness. GAPI and AGREE provide fully descriptive three-colored pictograms. The main disadvantage of GAPI is complexity compared to NEMI and ESA. AGREE has the merits of simplicity and automation over GAPI. Based on the results, recommendations are made for ESA, GAPI, and AGREE tools, which provide reliable and precise results about the greenness of the method. Planning for the greenness of analytical methods should be assured before practical trials in a laboratory for reduction of chemical hazards released into the environment. Moreover, inclusion of the evaluation of greenness of analytical methods in method validation protocols is strongly recommended.

Introduction: Novel manipulations of the well-known classical least squares multivariate calibration model were explained in detail as a comparative analytical study in this research work. In addition to the application of plain classical least squares model, two preprocessing steps were tried, where prior to modeling with classical least squares, first derivatization and orthogonal projection to latent structures were applied to produce two novel manipulations of the classical least square-based model. Moreover, spectral residual augmented classical least squares model is included in the present comparative study. Quantitative determination of pyridostigmine bromide in the presence of its two related substances; impurity A and impurity B was considered as a case study to construct the comparison. Method: 3 factor 4 level design was implemented constructing a training set of 16 mixtures with different concentrations of the studied components. To investigate the predictive ability of the studied models; a test set consisting of 9 mixtures was constructed. Results: The key performance indicator of this comparative study was the root mean square error of prediction for the independent test set mixtures, where it was found 1.367 when classical least squares applied with no preprocessing method, 1.352 when first derivative data was implemented, 0.2100 when orthogonal projection to latent structures preprocessing method was applied and 0.2747 when spectral residual augmented classical least squares was performed. Conclusion: Coupling of classical least squares model with orthogonal projection to latent structures preprocessing method produced significant improvement of the predictive ability of it.

Objectives.Acute pancreatitis (AP) is a life-threatening condition. Using antioxidants in AP is insufficient and conflicting. Therefore, this study compared the effect of hydrogen sulfide (H2S) donor, sodium hydrosulfide (NaHS), leptin or curcumin pretreatment on AP induced by L-arginine.

A strain of Bacillus methylotrophicuswas isolated from a soil sample collected in Aswan eastern desert, which is known for its extremely arid climate. After fermentation of the strain in liquid culture and subsequent extraction, a bioassay-guided isolation procedure yielded five compounds: 2-benzyl-4H-pyran-4-one, named bacillopyrone (1), pyrophen (2), macrolactin A (3) and the cyclopeptides malformin A1 (4), and bacillopeptin A (5). The structures were determined by interpretation of nuclear magnetic resonance (NMR) spectroscopy and high resolution mass spectrometry (HR-MS) data. This is the first report on the isolation of compounds 1and 2from Bacillusspecies; compound 1 was reported previously as synthetic product. Bacillopyrone (1) exhibited moderate activity against the Gram-negative Chromobacterium violaceumwith minimum inhibitory concentration 266.6 μg/mL, while macrolactin A (3) and malformin A1 (4) inhibited Staphylococcus aureus(minimum inhibitory concentrations 13.3 and 133.3 μg/mL, respectively).

Multiwall carbon nanotubes-titanium oxide nanocomposite (MWCNTs-TiO2) was formed and used as a conductive material for modification of graphite electrode and tyrosinase immobilization. This nanocomposite showed good conductivity, and biocompatibility with the enzyme. Under optimum conditions, the current response was linear to catechol concentration from 0.2 to 2.7 mM with a sensitivity of 85.79 mA/M and a low detection limit of 0.014 μM, the proposed electrode shows good reproducibility and long-term stability till 25 d. The prepared biosensor was successfully used to measure the catechol in different water samples, with excellent results compared with the spectrophotometric method, at 95% confidence level.

Background: Microorganisms are highly diverse sources of bioactive natural products. A valuable set of fungi has been encountered in the hot Egyptian desert soils. The aims of this paper were to isolate soil thermophilic fungi and detect their bioactive metabolites. Methods: Direct incorporation method of soil into PDA medium is used for fungal isolation. The metabolic extracts of the isolated fungi were assayed against four bacterial species, Escherichia coli, Staphylococcus aureus, Neisseria lactamica and Bacillus subtilis. Phytochemical methods were used to isolate active compounds from Aspergillus japonicas. Their structures were determined by the interpretation of the NMR data and high resolution mass spectrometry (HRESIMS). Results: The Ethyl acetate extract of Aspergillus japonicus inhibited the growth of Bacillus subtilis, Escherichia coli, Neisseria lactamica and Staphylococcus aureus. Metabolomic investigation of A. japonicus extra-cellular secretion resulted in the isolation of nigragillin (1); and nigerazine B (2); along with five naphtho-γ-pyrones, flavoasperone (3); rubrofusarin B (4); dianhydroaurasperone C (5); fonsecinone A (6); and aurasperone A (7). The antimicrobial activity of the isolated compounds is also described in this paper. Conclusion: This is the first report on those secondary metabolites from A. japonicus as well as the first full NMR assignments of nigerazine B (2). A. japonicas Compounds 1, 3, 4 and 7 exhibited antibacterial activities against B. subtilis, E. coli, N. lactamica, and S. aureus. Aurasperone A (7), and flavasperone (3) were the most active compounds against the tested Gram positive and Gram negative bacteria.

Discoidin Domain Receptor 2 (DDR2) is a collagen-activated receptor kinase that, together with integrins, is required for cells to respond to the extracellular matrix. Ddr2loss-of-function mutations in humans and mice cause severe defects in skeletal growth and development. However, the cellular functions of Ddr2in bone are not understood. Expression and lineage analysis showed selective expression of Ddr2at early stages of bone formation in the resting zone and proliferating chondrocytes and periosteum. Consistent with these findings, Ddr2+cells could differentiate into hypertrophic chondrocytes, osteoblasts, and osteocytes and showed a high degree of colocalization with the skeletal progenitor marker, Gli1. A conditional deletion approach showed a requirement for Ddr2in Gli1-positive skeletal progenitors and chondrocytes but not mature osteoblasts. Furthermore, Ddr2knockout in limb bud chondroprogenitors or purified marrow-derived skeletal progenitors inhibited chondrogenic or osteogenic differentiation, respectively. This work establishes a cell-autonomous function for Ddr2in skeletal progenitors and cartilage and emphasizes the critical role of this collagen receptor in bone development.

AbstractContext: The number of patients with type 2 diabetes mellitus (T2DM) is progressively increasing, and diabetic cardiovascular complications have become a public health problem. Brain or B-type natriuretic peptide (BNP) is a cardiac hormone synthesized as a pre-pro-peptide. pro-BNP is produced by cleaving the signal peptide then two proprotein convertases, corin and furin cleave pro-BNP to form a biologically active hormone. Two corin single nucleotide polymorphisms (SNPs) have been reported to alter corin protein conformation and impair its biological activity.Objective: We aimed to investigate the potential role of corin and furin in comparison to BNP as biomarkers for predicting cardiovascular complications in T2DM patients. The association of corin gene SNPs with corin levels was also examined.Methods: Seventy-five subjects were recruited in this study, including 25 T2DM patients with complications, 25 T2DM patients without complications as well as 25 healthy subjects. Plasma BNP, corin and furin levels were measured using enzyme-linked immunosorbent assays. Two corin SNPs were genotyped using allele specific oligonucleotide-polymerase chain reaction.Results: Both furin and BNP were found to be more sensitive than corin (80% versus 56%, p = 0.008), whereas furin showed higher specificity when compared to BNP (96% versus 84%, p = 0.041) and corin (96% versus 64%, p < 0.0001) in predicting cardiovascular complications in T2DM patients. Corin SNPs are not associated with corin levels, neither in the entire study cohort nor in the subgroup of T2DM patients with cardiovascular complications (p > 0.05).Conclusions: Furin may be useful, either alone or in combination with other biomarkers, for cardiovascular risk stratification assessment in T2DM patients.

A validated, sensitive, and highly selective stability-indicating high-performance thin-layer chromatographic (HPTLC) method has been adopted for the quantitative determination of pyridostigmine bromide in the presence of its alkaline-induced degradation product and in pharmaceutical formulations. 3-hydroxy-N-methyl pyridinium bromide (3-OH NMP) is the metabolite, impurity, and alkaline-induced degradation product of pyridostigmine bromide (PB). Pyridostigmine bromide and its alkaline-induced degradation product were separated on silica gel HPTLC F254plates using methanol-ethyl acetate-triethyl amine-glacial acetic acid (9:1:0.5:0.05 by volume) as the developing system followed by scanning of the separated bands at 270 nm over a concentration range of 2–10 μg band−1with mean percentage recoveries of 99.84% (SD 1.384). The proposed method was successfully applied to the analysis of pyridostigmine bromide both in bulk powder and in pharmaceutical formulation without interference from other dosage form additives. The results obtained by the proposed method were statistically compared with those obtained by the reported HPLC method with no significant difference regarding both accuracy and precision, indicating the ability of the proposed method to be reliable and suitable for routine analysis of a drug product.

The mycobiota of the sandy soil of Egyptian beaches was investigated in thirty six sand samples collected from nine different localities in Egypt. The filamentous fungi were identified and assigned to thirty one genera and fifty one species. Greater populations as well as a wider spectrum range of fungal genera and species were obtained in sandy soil of Alexandria beach while Balteem beach was the poorest one. The total count of the genus or species was not depended upon cases of isolation. Most of the genera detected belonged to the Deuteromycotina with fewer proportions belonging to the Ascomycotina and Zygomycotina. The genera of highest incidence and their respective numbers of species were: Penicillium(35.72%, 6 species) and Aspergillus(30.28%, 16 species). The species which showed the highest incidence in all cases was P. chrysogenum,followed by P citrinum, A. flaws, Chaetomium murorumand Trichoderma viride.A few number of other genera and species were also detected.

Analysis of leaf exudates of Vicia fabausing paper chromatography to identify individual amino acids and sugars qualitatively was investigated. The results revealed that the number of identified amino acids detected in the leaf exudates of the susceptible plants was more than those of resistant plants. The results also showed an increase in the number of amino acids exuded by infected leaves, but no marked difference in sugars of infected and non infected plants. Lithium chloride application led to decrease in amino acid and sugar contents. The number of amino acids and sugars was also decreased with leaf age. Botrytis fabaeand the selected fungal species (Alternaria alternata, Fusarium oxysporumand Aspergillus niger) were used to show the effect of individual amino acid and sugar on their spore germination. It was observed that all amino acids stimulated the fungal spore germination except serine which inhibited its spore germination. In case of A. alternata, spore germination was stimulated by all amino acids except serine, alanine, glutamic acid, arginine and methionine which caused the inhibition. In case of F. oxysporum, aspartic and glutamic acids inhibited spore germination but the other amino acids stimulated its spore germination. Aspartic acid and phenyl alanine inhibited the spore germination of A. niger. All the identified sugars (galactose, glucose, fructose and rhamnose) stimulated spore germination of all tested fungi.

L’hyperplasie angio-lymphoïde avec éosinophilie (HALE) est une dermatose éosinophilique rare posant un problème thérapeutique. Le but de ce travail est d’étudier les aspects épidémio-cliniques et histologiques de cette entité en insistant sur la prise en charge thérapeutique.