Metal Concentrations in Tissues of Gadwall and Common Teal from Miankaleh and Gomishan International Wetlands,Iran

Biological Trace Element Research - Miankaleh and Gomishan International Wetlands are important wintering areas for waterbirds in the Caspian Sea region. Previous studies revealed increased...     

Metabolism of [U-13C]Aspartate by Astroglial Cultures: Nuclear Magnetic Resonance Analysis of the Culture Media

In brain the amino acid L-aspartate serves roles as: (1) putative transmitter, (2) protein precursor, (3) donor of atoms for the biosynthesis of pyrimidine and purine bases, and (4) fuel for energy metabolism. Astrocytes dominate aspartate clearance in brain, and in culture they take up aspartate and quickly metabolize it. In brain, only astrocytes were shown to express the enzymes for de novo pyrimidine biosynthesis. To gain more details about the spectrum of metabolites generated from aspartate and subsequently released by cultured astrocytes a ¹³C-nuclear magnetic resonance analysis was performed of [U-¹³C]aspartate supplemented incubation media exposed to astroglial cultures. The results show that astrocytes readily metabolize aspartate and release into their culture media ¹³C-isotopomers of lactate, glutamine, citrate and alanine. Despite the presence in astroglial cells of two tandem enzymes of pyrimidine biosynthesis and their mRNAs, pyrimidine nucleotide-related heterocyclic compounds such as dihydroorotate and orotate could not be detected in the culture media.     

Quantification and optimization of Candida albicans DNA in blood samples using Real- Time PCR

Background:

Candida albicans (C. albicans) is a major cause of candidaemia in people with impaired immunity. Blood culture is a “gold standard” for candidaemia detection but is time-consuming and relatively insensitive. We established a real-time PCR assay for C. albicans detection in blood by LightCycler PCR and melting curve analysis.

Methods:

Five milliliter blood samples from healthy volunteers were spiked with 10⁰-10⁶ C. albicans cells to determine the detection limit of our method. DNA was extracted from whole blood using glass beads and the QIAamp DNA Blood Mini Kit (Qiagen, Hilden Germany). DNA from C. albicans isolates were amplified with primers and inserted into Escherichia coli (E. coli) DH5α.1 cells with the TA cloning vector (Invitrogen). The plasmid was used for standardization and optimization. A quantitative PCR assay with the LightCycler amplification and detection system based on fluorescence resonance energy transfer (FRET) with two different specific probes was established. To assess the precision and reproducibility of real-time PCR the intra-assay precision was determined in six consecutive assays.

Results:

No cross-reactivity of the hybridization probes with the DNA of non-C. albicans species or human genomic DNA was observed, which confirmed its 100% specificity. The minimum limit detected was one C. albicans cell or 10⁰ CFU/ml (10 fg) per PCR reaction. The real-time PCR efficiency rate for Candida was high (E = 1.95). Melting curve analysis of C. albicans showed a specific melting peak temperature of 65.76 °C.

Conclusion:

The real-time PCR assay we developed is highly specific and sufficiently sensitive to detect the fungal load for early diagnosis of invasive candidiasis. Key Words: Invasive candidiasis, Real-time PCR, Candida albicans     

Physiology and proteome responses of two contrasting rice mutants and their wild type parent under salt stress conditions at the vegetative stage

Salinity is one of the major environmental limiting factors that affects growth and productivity of rice (Oryza sativa L.) worldwide. Rice is among the most sensitive crops to salinity, especially at early vegetative stages. In order to get a better understanding of molecular pathways affected in rice mutants showing contrasting responses to salinity, we exploited the power of 2-DE based proteomics to explore the proteome changes associated with salt stress response. Our physiological observations showed that standard evaluation system (SES) scores, Na⁺ and K⁺ concentrations in shoots and Na⁺/K⁺ ratio were significantly different in contrasting mutants under salt stress condition. Proteomics analysis showed that, out of 854 protein spots which were reproducibly detected, 67 protein spots showed significant responses to salt stress. The tandem mass spectrometry analysis of these significantly differentially accumulated proteins resulted in identification of 34 unique proteins. These proteins are involved in various molecular processes including defense to oxidative stresses, metabolisms, photosynthesis, protein synthesis and processing, signal transduction. Several of the identified proteins were emerged as key participants in salt stress tolerance. The possible implication of salt responsive proteins in plant adaptation to salt stress is discussed.     

Cytogenetic study on some Fritillaria species of Iran

Five species (14 ecotypes) belonging to three subgenera of ornamental-medicinal Iranian Fritillaria plant were chromosomally and karyotypically assessed, using squash technique and 1 % (w/v) aceto-orcein stain. All species were diploid (2n = 2x = 24) having mean chromosome length of 16.8 μm (14.2–18.6 μm). The satellites varied in number (1–4 pairs) and in size (1.27–3.01 μm): mostly locating on long arms. Four chromosome types (“m”, “sm”, “st”, “T”) formed 11 different karyotypic formulas: the latter is being reported for the first time in some ecotypes in either S1 or S4. Nine chromosomal parameters were calculated. ANOVA verified intra- and inter-specific chromosomal variation in examined Iranian Fritillaria species. Twelve different methods were used to assess the degree of karyotype asymmetry. Among those, one qualitative (Stebbins classification) and seven quantitative (TF %, CV_TL, DI, AsK %, A2, Rec, CG %) parameters verified that S2 and S5 species were recognized as having the most asymmetrical and symmetrical karyotypes, respectively.     

Dose-dependent therapeutic effects of topical 1,25 OH-vitamin D3 on corneal wound healing

Molecular Biology Reports - Conflicting results have been reported regarding the effects of 1,25 OH-vitamin D3 on corneal wound healing. Therefore, we undertook this study to determine whether the...     

Interactions of anthropometric indices,rs9939609 FTO gene polymorphism and breast cancer: A case-control study

Contradictory results were reported on the effect of fat mass- and obesity-associated (FTO) gene and anthropometric measurements on breast cancer (BC). This study aimed to assess the interactions between rs9939609 polymorphism of FTO gene, anthropometric indices and BC risk in Iranian women. This case-control study was performed on 540 women including 180 women with BC and 360 healthy women in Tehran, Iran. Physical activity and dietary intakes were assessed by validated questionnaires. Data on sociodemographic and pathologic factors of the participants as well as their blood samples were collected. The rs9939609 FTO gene polymorphism was genotyped using the tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR). No significant association was found between BC and risk allele of FTO rs9939609 polymorphism after adjustments for the confounders. However, there was a significant association between rs9939609 polymorphism risk allele and BC risk in females with overweight, even after adjusting for age, family history of BC, abortion, BMI and the number of pregnancies (P < .05). The association was disappeared after further adjustments for lifestyle factors including smoking, alcohol consumption, calorie and macronutrients intake, and physical activity. The FTO gene polymorphism was associated with the risk of BC in overweight individuals. This association was influenced by environmental factors including diet, alcohol consumption and smoking. Future studies are required to confirm the association between the FTO gene and BC in overweight females and to identify the underlying mechanisms.     

Crop proteomics: aim at sustainable agriculture of tomorrow

The advent of proteomics has made it possible to identify a broad spectrum of proteins in living systems. This capability is especially useful for crops as it may give clues not only about nutritional value, but also about yield and how these factors are affected by adverse conditions. In this review, we describe the recent progress in crop proteomics and highlight the achievements made in understanding the proteomes of major crops. The major emphasis will be on crop responses to abiotic stresses. Rigorous genetic testing of the role of possibly important proteins can be conducted. The increasing ease with the DNA, mRNA and protein levels can be conducted and connected suggests that proteomics data will not be difficult to apply to practical crop breeding.