Synthesis and investigation of antimicrobial activity and spectrophotometric and dyeing properties of some novel azo disperse dyes based on naphthalimides

A series of novel disperse dyes containing azo group were synthesized through a diazotization and coupling process. The 4‐amino‐N‐2‐aminomethylpyridine‐1,8‐naphthalimide was diazotized by nitrosylsulphuric acid and coupled with various aromatic amines such as N,N‐diethylaniline, N,N‐dihydroxyethylaniline, 8‐hydroxyquinoline, and 2‐methylindole. Chemical structures of the synthesized dyes were characterized by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), proton nuclear magnetic resonance (¹H NMR), carbon nuclear magnetic resonance (¹³C NMR), elemental analysis, and ultraviolet–visible (UV–visible) spectroscopy. The spectrophotometric data of all dyes were evaluated in various solvents with different polarity. Eventually, the dyes were applied on polyamide fabrics in order to investigate their dyeing properties. The fastness properties of the dyed fabrics such as wash, light, and rubbing fastness degrees were measured by standard methods. Moreover, the color gamut of the synthesized dyes was measured on polyamide fabrics. Results indicated that some of the synthesized dyes were able to dye polyamide fabrics with deep shades. They had very good wash and rubbing fastness degrees and moderate‐to‐good light fastness on polyamide fabrics. The antibacterial and antifungal activities of the synthesized dyes were evaluated in soluble state and on the dyed fabrics. The results indicated that dye 2 containing N,N‐dihydroxyethylaniline as coupler had the highest activity against all the bacteria and fungi used. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1086–1095, 2015     

Diffusion of MRI and CT Contrast Agents in Articular Cartilage under Static Compression

Cartilage has a limited capacity for self-repair and focal damage can eventually lead to complete degradation of the tissue. Early diagnosis of degenerative changes in cartilage is therefore essential. Contrast agent-based computed tomography and magnetic resonance imaging provide promising tools for this purpose. However, the common assumption in clinical applications that contrast agents reach steady-state distributions within the tissue has been of questionable validity. Characterization of nonequilibrium diffusion of contrast agents rather than their equilibrium distributions may therefore be more effective for image-based cartilage assessment. Transport of contrast agent through the extracellular matrix of cartilage can be affected by tissue compression due to matrix structural and compositional changes including reduced pore size and fluid content. We therefore investigate the effects of static compression on diffusion of three common contrast agents: sodium iodide, sodium diatrizoate, and gadolinium diethylenetriamine-pentaacid (Gd-DTPA). Results showed that static compression was associated with significant decreases in diffusivities for sodium iodide and Gd-DTPA, with similar (but not significant) trends for sodium diatrizoate. Molecular mass of contrast agents affected diffusivities as the smallest one tested, sodium iodide, showed higher diffusivity than sodium diatrizoate and Gd-DTPA. Compression-associated cartilage matrix alterations such as glycosaminoglycan and fluid contents were found to correspond with variations in contrast agent diffusivities. Although decreased diffusivity was significantly correlated with increasing glycosaminoglycan content for sodium iodide and Gd-DTPA only, diffusivity significantly increased for all contrast agents by increasing fluid fraction. Because compounds based on iodine and gadolinium are commonly used for computed tomography and magnetic resonance imaging, present findings can be valuable for more accurate image-based assessment of variations in cartilage composition associated with focal injuries.     

Biology and demography of Glyphodes pyloalis Walker (Lepidoptera: Pyralidae) on mulberry

Lesser mulberry pyralid, Glyphodes pyloalis Walker, is a monophagous pest of mulberry and has recently been reported in northern Iran. The biology and life table of this pest were studied in controlled conditions (24 ± 1 °C, 75 ± 5% RH and 16:8 LD). Mortality rate, metamorphosis, appearance of adult insects and adult sex ratio were recorded daily. Data were analyzed based on an age-stage, two-sex life table. Developmental rate among individuals and between sexes were also considered. The developmental periods for the egg, first through fifth instar larvae, prepupae and pupae were 4.06 ± 0.03, 2.93 ± 0.03, 2.03 ± 0.02, 2.01 ± 0.01, 2.10 ± 0.03, 4.09 ± 0.03, 2.04 ± 0.02 and 9.7 ± 0.09 days, respectively. The mean total developmental period from egg to adult was 35.40 ± 0.37 days. The maximum adult longevity was 7 and 11 days for males and females, respectively. The pre-oviposition period lasted 2.14 ± 0.04 days. Laboratory observation showed that adults are nocturnal and female lay eggs at night. The intrinsic rate of increase (r_m) and the finite rate of increase (λ) were 0.14 ± 0.005 d^? 1 and 1.15 ± 0.01 d^? 1. The net reproductive rate (R₀), gross reproductive rate (GRR) and mean generation time (T) were 134.67 ± 20.6 female offspring, 294.71 ± 4.07 eggs/female and 34.44 ± 0.2 days, respectively. Life expectancy of freshly laid egg was 32.15 days.     

Detection and characterization of mutations in genes related to isoniazid resistance in Mycobacterium tuberculosis clinical isolates from Iran

Molecular Biology Reports - The global rise in drug-resistant Mycobacterium tuberculosis (M.tb), and especially the significant prevalence of isoniazid (INH)-resistance constitute a significant...     

The COP9 signalosome is vital for timely repair of DNA double-strand breaks

The DNA damage response is vigorously activated by DNA double-strand breaks (DSBs). The chief mobilizer of the DSB response is the ATM protein kinase. We discovered that the COP9 signalosome (CSN) is a crucial player in the DSB response and an ATM target. CSN is a protein complex that regulates the activity of cullin ring ubiquitin ligase (CRL) complexes by removing the ubiquitin-like protein, NEDD8, from their cullin scaffold. We find that the CSN is physically recruited to DSB sites in a neddylation-dependent manner, and is required for timely repair of DSBs, affecting the balance between the two major DSB repair pathways—nonhomologous end-joining and homologous recombination repair (HRR). The CSN is essential for the processivity of deep end-resection—the initial step in HRR. Cullin 4a (CUL4A) is recruited to DSB sites in a CSN- and neddylation-dependent manner, suggesting that CSN partners with CRL4 in this pathway. Furthermore, we found that ATM-mediated phosphorylation of CSN subunit 3 on S410 is critical for proper DSB repair, and that loss of this phosphorylation site alone is sufficient to cause a DDR deficiency phenotype in the mouse. This novel branch of the DSB response thus significantly affects genome stability.     

Association of genetic variants in complement factor H and factor H-related genes with systemic lupus erythematosus susceptibility

Systemic lupus erythematosus (SLE), a complex polygenic autoimmune disease, is associated with increased complement activation. Variants of genes encoding complement regulator factor H (CFH) and five CFH-related proteins (CFHR1-CFHR5) within the chromosome 1q32 locus linked to SLE, have been associated with multiple human diseases and may contribute to dysregulated complement activation predisposing to SLE. We assessed 60 SNPs covering the CFH-CFHRs region for association with SLE in 15,864 case-control subjects derived from four ethnic groups. Significant allelic associations with SLE were detected in European Americans (EA) and African Americans (AA), which could be attributed to an intronic CFH SNP (rs6677604, in intron 11, P _meta = 6.6×10⁻⁸, OR = 1.18) and an intergenic SNP between CFHR1 and CFHR4 (rs16840639, P _meta = 2.9×10⁻⁷, OR = 1.17) rather than to previously identified disease-associated CFH exonic SNPs, including I62V, Y402H, A474A, and D936E. In addition, allelic association of rs6677604 with SLE was subsequently confirmed in Asians (AS). Haplotype analysis revealed that the underlying causal variant, tagged by rs6677604 and rs16840639, was localized to a ∼146 kb block extending from intron 9 of CFH to downstream of CFHR1. Within this block, the deletion of CFHR3 and CFHR1 (CFHR3-1Δ), a likely causal variant measured using multiplex ligation-dependent probe amplification, was tagged by rs6677604 in EA and AS and rs16840639 in AA, respectively. Deduced from genotypic associations of tag SNPs in EA, AA, and AS, homozygous deletion of CFHR3-1Δ (P _meta = 3.2×10⁻⁷, OR = 1.47) conferred a higher risk of SLE than heterozygous deletion (P _meta = 3.5×10⁻⁴, OR = 1.14). These results suggested that the CFHR3-1Δ deletion within the SLE-associated block, but not the previously described exonic SNPs of CFH, might contribute to the development of SLE in EA, AA, and AS, providing new insights into the role of complement regulators in the pathogenesis of SLE.     

Invasive aspergillosis promotes tumor growth and severity in a tumor-bearing mouse model

Invasive aspergillosis increases in chronic immunosuppressive diseases such as cancer. There is little information about the mechanisms by which Aspergillus infection affects the immune regulation and microenvironment of cancer cells. Hence, this study was aimed at investigating the effect of invasive aspergillosis on immunosurveillance, metastasis, and prognosis of cancer in tumor-bearing mice. After implantation of mouse mammary tumor in BALB/c mice, they were infected with Aspergillus conidia intravenously. For comparison, groups of mice were experimentally infected with Aspergillus conidia or implanted with tumor cells separately. Seven days after Aspergillus infection, the serum levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) were measured by ELISA, and subsequently regulatory T lymphocytes were analyzed by flow cytometry. The survival of animals and mean tumor size were then determined. Our results indicated that tumor sizes in mice increased significantly after infection with Aspergillus conidia. Moreover, invasive aspergillosis enhanced the population of regulatory lymphocytes and level of TIMP-1. This study supports the idea that massive Aspergillus infection could stimulate tumor growth and increases the possibility of a bad prognosis. As a result, treatment of Aspergillus infection could be considered an important issue for efficient cancer therapy.     

A versatile method for functionalization and grafting of 2-hydroxyethyl cellulose (HEC) via Click chemistry

This article describes a versatile method for the modification of 2-hydroxyethyl cellulose (HEC) involving azide-alkyne cycloaddition reaction to impart neutral (ester) and ionic (carboxylic acid and 1(ry) amine) functionalities. The synthetic approach involved, first the introduction of the azide functionality to HEC and then followed by its cycloaddition reaction with several alkyne terminated compounds: namely ethyl propiolate, 5-hexynoic acid and propargyl amine. Sequential Click reactions were also demonstrated to be feasible by the successful synthesis of polydimethylsiloxane (PDMS) grafted HEC containing neutral (ester) and ionic (carboxylic acid and 1(ry) amine) functionalities. The Click chemistry was then further utilized similarly to graft poly(lactic acid) (PLA) and poly(ethylene glycol) (PEG) segments to HEC to access its hydrophobic and hydrophilic analogs, respectively. AFM analysis revealed that while HEC itself formed uniform oval features, the PLA grafted HEC exhibited a brushlike architecture. The formation of these brushlike structures suggested that the HEC backbone exhibits an extended conformation with the side chains stretched out. The resulting polymeric materials were characterized by solution and solid state (13)C NMR and FTIR spectroscopy.     

Comparison of Glutathione S-transferase Activity and Concentration in Aflatoxin-Producing and their Non-Toxigenic Counterpart Isolates

In this study, two techniques were used to compare the specific activity and total concentration of mycelial glutathione S-transferase (GST) in fungal strains isolated from natural sources. The fungi identified as Aspergillus parasiticus and Aspergillus flavus have been divided into two groups based on their ability to produce aflatoxins. Altogether 26 fungi were isolated, among which 12 were capable of producing varying levels of aflatoxin and 14 were proved to be non-toxigenic. GST specific activity in mycelial preparation was measured spectrophotometrically using 2,1-chloro-2,4-dinitrobenzene as the substrate. The results showed that the mean GST activity in toxigenic isolates was 25.06 +/- 9.8 mumol/mg protein/min which was 2.8-fold greater than that measured in non-toxigenic isolates (8.84 +/- 5.5 mumol/mg protein/min). Moreover, the GST concentration was compared in toxigenic and non-toxigenic isolates using an Enzyme Linked Immunosorbent Assay based on antigen (fungal preparation) and antibody (antibody produced against fungal GST in rabbit). The results of ELISA showed that the mean GST level in toxigenic and non-toxigenic fungi was 1.17 +/- 0.55 and 0.40 +/- 0.24, respectively. These results further confirm that the aflatoxin production in the fungal strains is correlated with GST expression and using ELISA, it is possible to discriminate aflatoxin-producing fungi from their non-toxigenic counterparts.