Homozygosity mapping in consanguineous families reveals extreme heterogeneity of non-syndromic autosomal recessive mental retardation and identifies 8 novel gene loci

Autosomal recessive gene defects are arguably the most important, but least studied genetic causes of severe cognitive dysfunction. Homozygosity mapping in 78 consanguineous Iranian families with nonsyndromic autosomal recessive mental retardation (NS-ARMR) has enabled us to determine the chromosomal localization of at least 8 novel gene loci for this condition. Our data suggest that in the Iranian population NS-ARMR is very heterogeneous, and they argue against the existence of frequent gene defects that account for more than a few percent of the cases. Mohammad Mahdi Motazacker and Masoud Garshasbi have contributed equally to this work.     

Induction of Hsp22 (HspB8) by estrogen and the metalloestrogen cadmium in estrogen receptor-positive breast cancer cells

Estrogen (E2) plays a critical role in the etiology and progression of human breast cancer. The estrogenic response is complex and not completely understood, including in terms of the involved responsive genes. Here we show that Hsp22 (synonyms: HspB8, E2lG1, H11), a member of the small heat shock protein (sHSP) superfamily, was induced by E2 in estrogen receptor-positive MCF-7 breast cancer cells, resulting in an elevated Hsp22 protein level, whereas it was not induced in estrogen receptor-negative MDA-MB-231 cells. This induction was prevented by the pure anti-estrogen ICI182780 (faslodex, fulvestrant), whereas tamoxifen, a substance with mixed estrogenic and antiestrogenic properties, had no major inhibitory effect on this induction, nor did it induce Hsp22 on its own. Cadmium (Cd) is an environmental pollutant with estrogenic properties (metalloestrogen) that has been implicated in breast cancer. Treatment of MCF-7 cells with Cd also resulted in induction of Hsp22, and this induction was also inhibited by ICI182780. In live MCF-7 cells, Hsp22 interacted at the level of dimers with Hsp27, a related sHSP, as was shown by quantitative fluorescence resonance energy transfer measurements. In cytosolic extracts of MCF-7 cells, most of the E2- and Cd-induced Hsp22 was incorporated into high-molecular mass complexes. In part, Hsp22 and Hsp27 were components of distinct populations of these complexes. Finally, candidate elements in the Hsp22 promoter were identified by sequence analysis that could account for the induction of Hsp22 by E2 and Cd. Taken together, Hsp22 induction represents a new aspect of the estrogenic response with potential significance for the biology of estrogen receptor-positive breast cancer cells.     

Antibiotic resistance,biofilm production ability and genetic diversity of carbapenem-resistant Pseudomonas aeruginosa strains isolated from nosocomial infections in southwestern Iran

Molecular Biology Reports - This study was aimed to evaluate the antibiotic resistance, biofilm formation, and genetic diversity of carbapenem-resistant Pseudomonas aeruginosa (CRPA) strains...     

The correlation of long non-coding RNAs IFNG-AS1 and ZEB2-AS1 with IFN-γ and ZEB-2 expression in PBMCs and clinical features of patients with coronary artery disease

Molecular Biology Reports - Aberrant expression of long non-coding RNAs (lncRNAs) can contribute to the pathogenesis of coronary artery disease (CAD). In this study, we aimed to evaluate the...     

Evaluation of large scale quantitative proteomic assay development using peptide affinity-based mass spectrometry

Stable isotope standards and capture by antipeptide antibodies (SISCAPA) couples affinity enrichment of peptides with stable isotope dilution and detection by multiple reaction monitoring mass spectrometry to provide quantitative measurement of peptides as surrogates for their respective proteins. In this report, we describe a feasibility study to determine the success rate for production of suitable antibodies for SISCAPA assays in order to inform strategies for large-scale assay development. A workflow was designed that included a multiplex immunization strategy in which up to five proteotypic peptides from a single protein target were used to immunize individual rabbits. A total of 403 proteotypic tryptic peptides representing 89 protein targets were used as immunogens. Antipeptide antibody titers were measured by ELISA and 220 antipeptide antibodies representing 89 proteins were chosen for affinity purification. These antibodies were characterized with respect to their performance in SISCAPA-multiple reaction monitoring assays using trypsin-digested human plasma matrix. More than half of the assays generated were capable of detecting the target peptide at concentrations of less than 0.5 fmol/μl in human plasma, corresponding to protein concentrations of less than 100 ng/ml. The strategy of multiplexing five peptide immunogens was successful in generating a working assay for 100% of the targeted proteins in this evaluation study. These results indicate it is feasible for a single laboratory to develop hundreds of assays per year and allow planning for cost-effective generation of SISCAPA assays.     

Evolutionary hypothesis of telomere length in primary breast cancer and brain tumour patients: a tracer for genomic-tumour heterogeneity and instability

It was previously reported that tumour samples had shorter telomeres than the surrounding normal tissue. Hereby, the initial sign of correlation between malignant tissue and telomere behaviour could be noticed. Bridging knowledge between germ and somatic cells could facilitate understanding cellular evolution. The aim of our investigation was to provide evidence for the evolutionary hypothesis of TL (telomere length) in primary BC (breast cancer) and BTs (brain tumours), which might be applied as a prognostic and/or predictive marker. DNA extraction from the frozen tissues was performed using high pure PCR template preparation kit. Standard protocol of Telo TTAGGG Telomere Length Assay kit, a non‐radioactive chemiluminescent assay, was used. The protein expression in extracted cells was analysed by immunofluorescence. We also detected telomerase activity. The G/T (genomic/tumour ratio) for TL in two groups of patients affected with primary BC and primary BT revealed significant differences in both BC patients (P=0.025) and in BTs (P=0.001). The pattern of telomere signals by Q‐FISH (quantitative fluorescent in situ hybridization) show that in all samples, except one, SI (signal intensity) has been significantly decreased in tissue related to blood, either in BC patients or in patients with BTs (0.041≥P≥0.001). However, the data achieved by Q‐FISH support the results of Southern blot. These data reflect a significant diversity either in BC or in BT patients, providing evidence for the evolutionary hypothesis of TL in cancer development and progression.     

New bioengineering insights into human neural precursor cell expansion in culture

Understanding initial cell growth, interactions associated with the process of expansion of human neural precursor cells (hNPCs), and cellular events pre- and postdifferentiation are important for developing bioprocessing protocols to reproducibly generate multipotent cells that can be used in basic research or the treatment of neurodegenerative disorders. Herein, we report the in vitro responses of telencephalon hNPCs grown in a serum-free growth medium using time-lapse live imaging as well as cell-surface marker, aggregate size, and immunocytochemical analyses. Time-lapse analysis of hNPC initial expansion indicated that cell-surface attachment in stationary culture and the frequency of cell-cell interaction in suspension conditions are important for subsequent aggregate formation and hNPC growth. In the absence of cell-surface attachment in low-attachment stationary culture, large aggregates of cells were formed and expansion was adversely affected. The majority of the telencephalon hNPCs expressed CD29, CD90, and CD44 (cell surface markers involved in cell-ECM and cell-cell interactions to regulate biological functions such as proliferation), suggesting that cell-surface attachment and cell-cell interactions play a significant role in the subsequent formation of cell aggregates and the expansion of hNPCs. Before differentiation, about 90% of the cells stained positive for nestin and expressed two neural precursor cells surface markers (CD133 and CD24). Upon withdrawal of growth cytokines, hNPCs first underwent cell division and then differentiated preferentially towards a neuronal rather than a glial phenotype. This study provides key information regarding human NPC behavior under different culture conditions and favorable culture conditions that are important in establishing reproducible hNPC expansion protocols.     

Antibacterial activity and chemical composition of the essential oil of Grammosciadium platycarpum Boiss. from Iran

The chemical composition of the essential oils obtained from two samples (GP1 and GP2) of Grammosciadium platycarpum Boiss. was analyzed by GC and GC-MS. The analysis of the oils resulted in the identification of twenty-two constituents. Linalool (79.0%-GP1, 81.8%-GP2) and limonene (10.0%, 5.8%) were found to be the major components, respectively. The in vitro antibacterial activities of these oils and their main compounds against seven Gram-positive and Gram-negative bacteria were investigated. The results exhibited that the total oils and their major components possess strong to moderate activities against all the tested bacteria except for Pseudomonas aeruginosa.