Cytokine gene polymorphism and graft-versus-host disease: a survey in Iranian bone marrow transplanted patients

Graft versus host disease (GVHD) is a major complication of bone marrow transplantation (BMT). Numerous studies have shown the potential role of cytokine genotypes in the occurrence of GVHD. In this retrospective, case–control study we aimed to investigate the association between 13 cytokine genes and acute GVHD (aGVHD) after HLA-identical sibling BMT in 91 Iranian subjects. Negative association was found between aGVHD and donor IL-10/GCC haplotype or donor IL-4Ra-A allele in the population study. When compared within the leukemia subgroup, we observed positive association between recipient IL-1α ?889/C allele and aGVHD. Also there were negative association between recipient IL-10/CAA haplotype and donor IL-4Ra/A allele and development of aGVHD. Among the different genotypes only donor IL-4Ra and donor IL-12 showed significant association. We conclude that several cytokine polymorphisms are positively and negatively associated with aGVHD in Iranian HLA matched siblings, of which IL-4Ra and IL-12 may play important roles.     

Liebenberg syndrome is caused by a deletion upstream to the PITX1 gene resulting in transformation of the upper limbs to reflect lower limb characteristics

Liebenberg syndrome (MIM 186550) is a very rare autosomal dominant condition characterized by three main features: dysplasia of all of the bony components of the elbow joint, abnormalities in the shape of carpal bones, and brachydactyly. In this paper, we report a Saudi Arabian family with Liebenberg syndrome. Comparative genomic hybridization (CGH) revealed a 275-kb deletion within the cytogenetic band 5q31.1 which contains the H2AFY gene and 190,428 bp of its downstream region. The deleted region is upstream to the PITX1 gene. The radiological features in the upper limbs of all affected members of the family were almost identical to the phenotype in the mouse model with ectopic expression of Pitx1 in the forelimbs. We therefore re-define the phenotype of Liebenberg syndrome as a transformation of the upper limbs to reflect lower limb characteristics and speculate that the area of deletion contains a regulatory sequence that suppresses the expression of PITX1 in the upper limb buds.     

Combinatorial materials research applied to the development of new surface coatings IV. A high-throughput bacterial biofilm retention and retraction assay for screening fouling-release performance of coatings

Abstract

A high-throughput bacterial biofilm retention screening method has been augmented to facilitate the rapid analysis and down-selection of fouling-release coatings for identification of promising candidates. Coatings were cast in modified 24-well tissue culture plates and inoculated with the marine bacterium Cytophaga lytica for attachment and biofilm growth. Biofilms retained after rinsing with deionised water were dried at ambient laboratory conditions. During the drying process, retained biofilms retracted through a surface de-wetting phenomenon on the hydrophobic silicone surfaces. The retracted biofilms were stained with crystal violet, imaged, and analysed for percentage coverage. Two sets of experimental fouling-release coatings were analysed with the high-throughput biofilm retention and retraction assay (HTBRRA). The first set consisted of a series of model polysiloxane coatings that were systematically varied with respect to ratios of low and high MW silanol-terminated PDMS, level of cross-linker, and amount of silicone oil. The second set consisted of cross-linked PDMS-polyurethane coatings varied with respect to the MW of the PDMS and end group functionality. For the model polysiloxane coatings, HTBRRA results were compared to data obtained from field immersion testing at the Indian River Lagoon at the Florida Institute of Technology. The percentage coverage calculations of retracted biofilms correlated well to barnacle adhesion strength in the field (R² = 0.82) and accurately identified the best and poorest performing coating compositions. For the cross-linked PDMS-polyurethane coatings, the HTBRRA results were compared to combinatorial pseudobarnacle pull-off adhesion data and good agreement in performance was observed. Details of the developed assay and its implications in the rapid discovery of new fouling-release coatings are discussed.     

Inhibitor binding studies of Mycobacterium tuberculosis MraY (Rv2156c): Insights from molecular modeling,docking, and simulation studies

Abstract

Tuberculosis (TB) is a contagious disease caused by Mycobacterium tuberculosis (M.tb) or tubercule bacillus, and H37Rv is the most studied clinical strain. The recent development of resistance to existing drugs is a global health-care challenge to control and cure TB. Hence, there is a critical need to discover new drug targets in M.tb. The members of peptidoglycan biosynthesis pathway are attractive target proteins for antibacterial drug development. We have performed in silico analysis of M.tb MraY (Rv2156c) integral membrane protein and constructed the three-dimensional (3D) structure model of M.tb MraY based on homology modeling method. The validated model was complexed with antibiotic muraymycin D2 (MD2) and was used to generate structure-based pharmacophore model (e-pharmacophore). High-throughput virtual screening (HTVS) of Asinex database and molecular docking of hits was performed to identify the potential inhibitors based on their mode of interactions with the key residues involved in M.tb MraY–MD2 binding. The validation of these molecules was performed using molecular dynamics (MD) simulations for two best identified hit molecules complexed with M.tb MraY in the lipid bilayer, dipalmitoylphosphatidyl-choline (DPPC) membrane. The results indicated the stability of the complexes formed and retained non-bonding interactions similar to MD2. These findings may help in the design of new inhibitors to M.tb MraY involved in peptidoglycan biosynthesis.     

Structural characterization of MG and pre-MG states of proteins by MD simulations,NMR, and other techniques

Almost all proteins fold via a number of partially structured intermediates such as molten globule (MG) and pre-molten globule states. Understanding the structure of these intermediates at atomic level is often a challenge, as these states are observed under extreme conditions of pH, temperature, and chemical denaturants. Furthermore, several other processes such as chemical modification, site-directed mutagenesis (or point mutation), and cleavage of covalent bond of natural proteins often lead to MG like partially unfolded conformation. However, the dynamic nature of proteins in these states makes them unsuitable for most structure determination at atomic level. Intermediate states studied so far have been characterized mostly by circular dichroism, fluorescence, viscosity, dynamic light scattering measurements, dye binding, infrared techniques, molecular dynamics simulations, etc. There is a limited amount of structural data available on these intermediate states by nuclear magnetic resonance (NMR) and hence there is a need to characterize these states at the molecular level. In this review, we present characterization of equilibrium intermediates by biophysical techniques with special reference to NMR.     

Antioxidant, anticancer and hepatoprotective activities of Cotoneaster horizontalis Decne extract as well as α-tocopherol and amygdalin production from in vitro culture

The phytochemical analysis of the ethanolic extract of branches of Cotoneaster horizontalis, Decne revealed the presence of: β-carotene, ascorbic acid and less amounts of α-tocopherol and amygdalin (vitamin B₁₇) in proportions of: 2,500, 70, 0.093, 0.334 mg 100 g^?1, respectively. Acute oral toxicity test revealed its safety profile. In vitro study revealed its good 2, 2-diphenyl-1-picrylhydrazyl radical scavenging and anticancer activities. Invivo study, simultaneous administration of this extract at a dose of 100 or 200 mg kg^?1 body weight for 4 weeks, exhibited a significant protection in a dose-dependant manner against hepatotoxicity induced by repeated dose of acetaminophen (1 g kg^?1 body weight day^?1, p.o.) by preserving the liver function parameters, hepatic redox state and serum lipid profile near the healthy levels. Consequently, in vitro culture was carried out on full or half strength of Murashige and Skoog medium supplemented with different concentrations of benzyl amino purine or kinetin provided shootlets production; different concentrations of 2,4-dichlorophenoxy acetic acid and naphthalene acetic acid showed an increase of callus. Determination of α-tocopherol and amygdalin in different shootlets and callus extracts showed a pronounced increases up to 30.62 and 3.69 mg 100 g^?1 in shootlet extract, respectively as well as 26.61 and 12.71 mg 100 g^?1 in callus extract, respectively, as compared with those of the mother plant (0.76 and 0.11 mg 100 g^?1 extract, respectively).     

Helophorus erzurumicus sp. n., a new species from Turkey and some notes on H. ponticus Angus, 1988 (Coleoptera: Hydrophilidae)

A new species of Helophorus Fabricius, 1775 is described from Erzurum, northeastern Turkey: Helophorus erzurumicus. In addition, distributional and morphological notes on H. ponticus Angus, 1988 are presented.     

Comparative study of mycelia growth and sporophore yield of Auricularia polytricha (Mont.) Sacc on selected palm oil wastes as fruiting substrate

The potential for using agricultural and industrial by-products as substrate for the production of the edible mushroom, Auricularia polytricha, was evaluated using several formulations of selected palm oil wastes mixed with sawdust and further supplemented with selected nitrogen sources. The best substrate formulations were sawdust (SD) mixed with oil palm frond (OPF; 90:10) added with 15 % spent grain (SG) and sawdust mixed with empty fruit bunch (EFB; 50:50) added with 10 % spent grain (SG) with mycelia growth rate of 8 mm/day and 7 mm/day respectively. These two substrate formulations were then subjected to different moisture content levels (65 %, 75 % and 85 %). Highest total fresh sporophore yield at 0.43 % was obtained on SD?+?OPF (90:10)?+?15 % SG at 85 % moisture content, followed closely by SD?+?EFB (50:50)?+?10 % SG with 0.40 % total yield, also at 85 % moisture content. Each of the substrate formulations at 85 % moisture content gave the highest biological efficiency (BE) at 288.9 % and 260.7 %, respectively. Both yield and biological efficiency of A. polytricha on these two formulations were almost three times higher when compared to sawdust substrate alone, thus proving the potential of these formulations to improve yield of this mushroom.     

A preliminary survey on the occurrence of mycotoxigenic fungi and mycotoxins contaminating red rice at consumer level in Selangor, Malaysia

Red rice is a fermented product of Monascus spp. It is widely consumed by Malaysian Chinese who believe in its pharmacological properties. The traditional method of red rice preparation disregards safety regulation and renders red rice susceptible to fungal infestation and mycotoxin contamination. A preliminary study was undertaken aiming to determine the occurrence of mycotoxigenic fungi and mycotoxins contamination on red rice at consumer level in Selangor, Malaysia. Fifty red rice samples were obtained and subjected to fungal isolation, enumeration, and identification. Citrinin, aflatoxin, and ochratoxin-A were quantitated by ELISA based on the presence of predominant causal fungi. Fungal loads of 1.4?×?10⁴ to 2.1?×?10⁶?CFU/g exceeded Malaysian limits. Monascus spp. as starter fungi were present in 50 samples (100 %), followed by Penicillium chrysogenum (62 %), Aspergillus niger (54 %), and Aspergillus flavus (44 %). Citrinin was present in 100 % samples (0.23–20.65 mg/kg), aflatoxin in 92 % samples (0.61–77.33 μg/kg) and Ochratoxin-A in 100 % samples (0.23–2.48 μg/kg); 100 % citrinin and 76.09 % aflatoxin exceeded Malaysian limits. The presence of mycotoxigenic fungi served as an indicator of mycotoxins contamination and might imply improper production, handling, transportation, and storage of red rice. Further confirmatory analysis (e.g., HPLC) is required to verify the mycotoxins level in red rice samples and to validate the safety status of red rice.