A new species of Myrmozercon Berlese (Acari,Mesostigmata, Laelapidae) associated?with?ant?from?Iran

This paper report on a new species of mites of the genus Myrmozercon associated with ant in Iran – Myrmozercon cyrusi Ghafarian and Joharchi sp. n. was collected associated of the Monomorium sp. in Kenevist Rural District in the Central District of Mashhad County, Khorasan Razavi Province, Iran. This new species is described and illustrations provided. Myrmozercon ovatum Karawajew, 1909 is suspected to be a junior synonym of Myrmozercon brevipes Berlese, 1902 and host-specificity and host range of Myrmozercon are also reviewed.     

Pollen morphology of Astragalus section Hymenostegis (Fabaceae) and evaluation of its systematic implications

Astragalus is with nearly 3000 described species the largest genus of flowering plants. So far analyses of pollen characters have only been conducted for a few species of the groups within the genus. Here we analyse pollen grains of 22 species representative for Astragalus section Hymenostegis using scanning electron microscopy. We found the basic shape of the pollen grains to be oblate-spheroidal and apertures to be tricolpate as for other eudicots. The sculpturing pattern of the exine is micro-reticulate. Pollen grains show low morphological variation among different species of this section, but differences occur between sections of the genus. We conclude that the vast morphological differentiation that occurred during the rapid radiation of section Hymenostegis was not accompanied by comparable differentiation in pollen morphology.     

Topical application of aminopeptidase N-neutralizing antibody accelerates wound closure

Upon release from keratinocytes, 14-3-3 sigma (also known as stratifin) acts on the dermal fibroblast and modulates its production of extracellular matrix proteins. Subsequent to the recent identification as a receptor responsible for stratifin-mediated matrix turnover in dermal fibroblasts, aminopeptidase N has been implicated in the regulation of epidermal?Cdermal communication and expression of key matrix proteases and adhesion molecules. In light of the growing importance of aminopeptidase N in modulation of the fibroblast phenotype, the present study evaluates the potential of targeting the ectoenzyme in cutaneous repair, and demonstrates that neutralization of aminopeptidase N led to acceleration of wound closure. This was attributed to at least in part an increase of collagen deposition and fibroblast contractility in the granulation tissue. These findings confirmed the important role of aminopeptidase N in post-injury tissue remodeling and wound contraction.     

Study on allergenicity of Thuja orientalis pollen grains in rat

Cupressaceae pollen allergy is an important cause of pollen allergy throughout the world. Prevalence of allergy to Cupressaceae pollen has increased significantly during the winter over the past 3 decades because of extensive planting of cypress trees for different purposes. Thuja orientalis (Cupressaceae) is a naturally grown plant in Iran and is widely cultivated as a common ornamental plant in this country and other ones. Allergenicity of its pollen has been established, but to this day no allergenic component has been detected. The aim of this research is to study allergenicity and evaluate the immunoglobulin E reactivity to T. orientalis pollen extracts. Pollen grains were directly collected from mature male cones of trees. Pollen proteins were extracted and were analyzed by SDS-PAGE. Total protein content of pollen extracts was measured by Bradford assay. Immunoblotting using the serum of sensitized rats showed a single immunogenic band at about 44KD in pollen extracts. Result of this research proved that pollen grains of T. orientalis are allergenic.     

Design of Localized Surface Plasmon Resonance (LSPR) Biosensor for Immunodiagnostic of E. coli O157:H7 Using Gold Nanoparticles Conjugated to the Chicken Antibody

E. coli O157:H7 is one of the most important pathogens in food-borne diseases and is the main cause of the pseudo pandemic development of hemorrhagic colitis and hemolytic uremic syndrome. Also E. coli O157:H7 is the most common serotype of Shiga-toxin-producing E. coli. Traditional methods for detecting E. coli O157:H7 are expensive, time-consuming, and less sensitive. A method with high sensitivity and high-resolution optical detection is utilizes the LSPR property of spherical gold nanoparticles (GNP). In this work, we constructed a novel nano-bio probe to detect E. coli O157:H7 by synthesizing citrate gold nanoparticle conjugated (non-covalent bond) with specific chicken anti-E. coli O157:H7 antibody (IgY) by changing the pH of the nanoparticles’ environment. UV-visible and DLS methods were used to confirm the bonding between the antibody and nanoparticles and the LSPR sensitivity of the nano-bio probe was evaluated by ELISA method. We could optically detect this bacterium in less than 2 h by measuring the LSPR band λ max shifts of GNPs. The sensitivity of this novel biosensor was determined by about 10 CFU/ml, using the LSPR property of spherical gold nanoparticles. So that, the LSPR λ max red shifted from 530 to 543 nm in presence of 10 CFU bacterium. In conclusion, this nano biosensor can be used to detect this important pathogen among the clinical specimens.

     

Mutations in the Reelin pathway are associated with abnormal expression of microglial IgG FC receptors in the cerebellar cortex

Microglia are the immune cells of the central nervous system involved in a variety of developmental processes, such as regulation of cell death and survival, spatial patterning, and contribute to the development of Purkinje cells (PCs) during migration. Microglia express immunoglobulin G Fc receptors (FcgRs). In this report, we describe microglial FcgR expression and its relation to abnormal PC migration in the cerebellum during development. To detect microglial FcgR, the direct anti-IgG (secondary antisera) and high concentrations of Triton X-100 were applied as a method for labeling microglial cells without the use of any specific primary antiserum. By using Acp2^?/? mice, which show an excessive PC migration into the molecular layer (ml), and 3 different types of mice with a null to alter the Reelin pathway (Reeler-, Dab1 (SCM)-, and Apoer mutant mice), we studied the location of PCs and the expression of FcgRs. Wild type littermates were used as controls in all studies. We show that the expression of microglial FcgRs was absent and PCs were ectopically located in the white matter in the cerebella of all mutant mice, except for the Acp2^?/? mice (PCs were located in the ml). These results suggest a role for FcgRs in the Reelin signaling pathway, not in regulating PC migration, but rather in the adaptation to an environment with a relatively large number of ectopically located PCs. However, the exact correlation between the ectopic location of PCs and lack of FcgRs in Reeler, SCM, and Apoer^?/? mice and the presence of FcgRs and directed PC location in the ml in Acp2^?/? mice are yet to be determined.

     

Prevention of thermal aggregation of an allosteric protein by small molecules: some mechanistic insights

Detailed knowledge of conformation and dynamics of native, intermediate and unfolded states of a protein is essential in searching for effective small molecules to prevent its aggregation. In a recent study we have demonstrated how allosteric effectors may influence protein-protein interactions at high temperatures using glutamate dehydrogenase (GDH) as a model allosteric protein. In the present study, thermal aggregation of this well-characterized enzyme was investigated in the presence of a number of amino acids (including Gly, Glu, Trp, Pro, Lys, Arg), polyamines (putrescine and spermidine) and chaperone-like molecules (cyclodextrins and caseins) as non-specific effectors. It was shown that some amino acids and polyamines may suppress aggregation via interaction with native species and may preserve the activity of the enzyme while cyclodextrins and caseins may exert their anti-aggregation potential via binding to aggregation-prone intermediates, without having any capacity to protect its native structure from unfolding. Observations describing the similarities and differences between the specific ligands and non-specific small molecules related to their interaction with native and aggregation-prone states of GDH are presented and discussed. It is argued that the type of studies described in the present communication is useful for the development of effective strategies for prevention of aggregation by small molecules.     

Morphology and fine structure of Acipenser persicus (Acipenseridae, Chondrostei) spermatozoon: Inter-species comparison in Acipenseriformes

This study describes morphology and fine structure of the Persian sturgeon (Acipenser persicus) (Acipenseridae, Chondrostei) spermatozoon. The results show that the spermatozoon of A. persicus is differentiated into an elongated head (length: mean±SD: 7.1±0.5μm) with an acrosome (length: 1.2±0.2μm), a cylindrical midpiece (length: 1.8±0.5μm), a flagellum (length: 50.3±5.9μm) and a total length of 59.2±6.2μm. Ten posterolateral projections (PLPs) arise from the posterior edge of the acrosome and there were 3 endonuclear canals that traversed the nucleus from the acrosomal end to the basal nuclear fossa region. Three to six mitochondria were in peripheral midpiece and the proximal and distal centrioles were located near to "implantation fossa" and basement of the flagellum. The axoneme has a typical eukaryotic structure composed of 9 peripheral microtubules and a central pair of single microtubule surrounded by the plasma membrane. Lateral fins were observed along the flagellum. The fins started and ended at 0.5-1μm from midpiece and at 4-6μm from the end of flagellum. There were significant differences in the size of almost all measured morphological parameters between males and flagellar, midpiece and nucleus characters were more isolated parameters that can be considered for detecting inter-individual variations. This study showed that sperm morphology and fine structure are similar among sturgeon species, but the dimensions of the parameters may differ.     

Identification of tubular heparan sulfate as a docking platform for the alternative complement component properdin in proteinuric renal disease

Properdin binds to proximal tubular epithelial cells (PTEC) and activates the complement system via the alternative pathway in vitro. Cellular ligands for properdin in the kidney have not yet been identified. Because properdin interacts with solid-phase heparin, we investigated whether heparan sulfate proteoglycans (HSPG) could be the physiological ligands of properdin. Kidneys from proteinuric rats showed colocalization of syndecan-1, a major epithelial HSPG, and properdin in the apical membranes of PTEC, which was not seen in control renal tissue. In vitro, PTEC did not constitutively express properdin. However, exogenous properdin binds to these cells in a dose-dependent fashion. Properdin binding was prevented by heparitinase pretreatment of the cells and was dose-dependently inhibited by exogenous heparin. ELISA and surface plasmon resonance spectroscopy (BIAcore) showed a strong dose-dependent interaction between heparan sulfate (HS) and properdin (K(d) = 128 nm). Pretreatment of HSPG with heparitinase abolished this interaction in ELISA. Competition assays, using a library of HS-like polysaccharides, showed that sulfation pattern, chain length, and backbone composition determine the interaction of properdin with glycosaminoglycans. Interestingly, two nonanticoagulant heparin derivatives inhibited properdin-HS interaction in ELISA and BIAcore. Incubation of PTEC with human serum as complement source led to complement activation and deposition of C3 on the cells. This C3 deposition is dependent on the binding of properdin to HS as shown by heparitinase pretreatment of the cells. Our data identify tubular HS as a novel docking platform for alternative pathway activation via properdin, which might play a role in proteinuric renal damage. Our study also suggests nonanticoagulant heparinoids may provide renoprotection in complement-dependent renal diseases.