Ion composition and osmolarity of Caspian Sea ctenophore, Mnemiopsis leidyi, in different salinities

The aim was to study osmotic and ionic regulation in alien ctenophore, Mnemiopsis leidyi (total length of 1.5-3 cm), acclimated gradually to artificial sea water of different salinities (8, 13, 18 and 23 ppt) in laboratory conditions (24 ± 2 °C) with the salt composition and proportion of the Caspian Sea. Results showed that this species is hyper-osmoconformer (maintaining internal osmolarity 2-22 mOsmol l^{− 1} above external) in non-lethal salinities ranging from 8 to 23 ppt. The results of ionic regulatory investigations revealed that this species can regulate Ca²⁺ and SO₄²⁻ so that the concentration of Ca²⁺ in the internal fluid and SO₄²⁻ in the external fluid were significantly more in 8 and 13 ppt, respectively. No regulation was observed about other ions such as Cl⁻, Mg²⁺ and K⁺ in the mentioned salinities.     

Effect of thymoquinone and Nigella sativa seeds oil on lipid peroxidation level during global cerebral ischemia-reperfusion injury in rat hippocampus

It has been previously reported that Nigella sativa oil (NSO) and thymoquinone (TQ), active constituent of N. sativa seeds oil, may prevent oxidative injury in various models. Therefore, we considered the possible effect of TQ and NSO on lipid peroxidation level following cerebral ischemia-reperfusion injury (IRI) in rat hippocampus. Male NMRI rats were divided into nine groups, namely, sham, control, ischemia and ischemia treated with NSO or TQ. TQ (2.5, 5 and 10 mg/kg), NSO (0.048, 0.192 and 0.384 mg/kg), phenytoin (50 mg/kg, as positive control) and saline (10 ml/kg, as negative control) were injected intraperitoneally immediately after reperfusion and the administration was continued every 24h for 72 h after induction of ischemia. The transient global cerebral ischemia was induced using four-vessel-occlusion method for 20 min. Lipid peroxidation level in hippocampus portion was measured as malondialdehyde (MDA) based on its reaction with thiobarbituric acid (TBA) following ischemic insult. The transient global cerebral ischemia induced a significant increase in TBA reactive substances (TBARS) level (p<0.001), in comparison with sham-operated animal. Pretreatment with TQ and NSO were resulted a significant decrease in MDA level as compared with ischemic group (66.9+/-1.5 vs. 297+/-2.5 nmol/g tissue for TQ, 10 mg/kg; p<0.001 and 153.5+/-1.3 nmol/g tissue for NSO, 0.384 mg/kg; p<0.001). Using a reversed-phase HPLC system, the amount of TQ in NSO was also quantified and was 0.58% w/w. These results suggest that TQ and NSO may have protective effects on lipid peroxidation process during IRI in rat hippocampus.     

Distinct domains of yeast cortical tag proteins Bud8p and Bud9p confer polar localization and functionality

In Saccharomyces cerevisiae, diploid yeast cells follow a bipolar budding program, which depends on the two transmembrane glycoproteins Bud8p and Bud9p that potentially act as cortical tags to mark the cell poles. Here, we have performed systematic structure-function analyses of Bud8p and Bud9p to identify functional domains. We find that polar transport of Bud8p and Bud9p does not depend on N-terminal sequences but instead on sequences in the median part of the proteins and on the C-terminal parts that contain the transmembrane domains. We show that the guanosine diphosphate (GDP)/guanosine triphosphate (GTP) exchange factor Bud5p, which is essential for bud site selection and physically interacts with Bud8p, also interacts with Bud9p. Regions of Bud8p and Bud9p predicted to reside in the extracellular space are likely to confer interaction with the N-terminal region of Bud5p, implicating indirect interactions between the cortical tags and the GDP/GTP exchange factor. Finally, we have identified regions of Bud8p and Bud9p that are required for interaction with the cortical tag protein Rax1p. In summary, our study suggests that Bud8p and Bud9p carry distinct domains for delivery of the proteins to the cell poles, for interaction with the general budding machinery and for association with other cortical tag proteins.     

Serum level and tumor tissue expression of Ribonucleotide-diphosphate Reductase subunit M2 B: a potential biomarker for colorectal cancer

Molecular Biology Reports - This study explored the applicability of serum level and tissue expression of Ribonucleotide-diphosphate Reductase subunit M2 B (RRM2B) as reliable biomarkers for...     

Chemical composition and antifungal efficacy of five essential oils against Calonectria pseudonaviculata,the causal agent of boxwood blight: an in vitro study

Recent epidemics of box (boxwood) blight caused by the fungus Calonectria pseudonaviculata in Hyrcanian forests led to the search for eco-friendly fungicides. Essential oils (EOs) of medicinal plants undoubtedly have been highlighted as a new therapeutic approach. In this study, EOs from Cuminum cyminum, Lavandula angustifolia, Thymus daenensis, Trachyspermum copticum and Hyssopus officinalis were evaluated for their inhibitory activities against C. pseudonaviculata Cy-08 in vitro. Quantitative and qualitative composition variations of the EOs were also analysed by GC–MS. Based on the high inhibitory efficacy and low related EC₅₀, MFC and MIC values, T. copticum, L. angustifolia and Th. daenensis EOs can be mentioned as those providing extraordinary efficacy against Cy-08, respectively. Major chemical components of T. copticum, L. angustifolia and Th. daenensis EOs were thymol, linalyl acetate and thymol, respectively. Thymol and linalyl acetate may be the most effective compounds against C. pseudonaviculata.     

Timeline (Bioavailability) of Magnesium Compounds in Hours: Which Magnesium Compound Works Best?

Biological Trace Element Research - Magnesium is an element of great importance functioning because of its association with many cellular physiological functions. The magnesium content of foods is...     

Suppressive Role of Boron on Adipogenic Differentiation and Fat Deposition in Human Mesenchymal Stem Cells

Biological Trace Element Research - Over the past years, adipose tissue has become an invaluable source of mesenchymal stem cells (MSCs) due to development of improved isolation methodologies. In a...     

Differentiation of neurosphere-derived rat neural stem cells into oligodendrocyte-like cells by repressing PDGF-α and Olig2 with triiodothyronine

One of the approaches for treating demyelination diseases is cytotherapy, and adult stem cells are potential sources. In this investigation, we tried to increase the yield of oligodendrocyte-like cells (OLCs) by inducing neural stem cells generated from BMSCs-derived neurospheres, which were used for deriving the neural stem cells (NSCs). The latter were induced into OLCs by heregulin, PDGF-AA, bFGF and triiodothyronine (T3). The BMSCs, NS, NSCs and OLCs were characterized by using immunocytochemistry for fibronectin, CD44, CD90, CD45, Oct-4, O4, Olig2, O1 and MBP markers. PDGF receptor α (PDGFR-α), Olig2 and MOG expression were evaluated by RT-PCR. The BMSCs expressed CD44, CD90, CD106 and Oct-4; the NSCs were immunoreactive to nestin and neurofilament 68. Incubation of the NSCs for 4 days with heregulin, PDGF-AA and bFGF resulted in their induction into oligodendrocyte progenitor-like cells (OPLCs), which immunoreacted to O4, Olig2 and O1, while Olig2 and PDGFR-α were detected by RT-PCR. Replacing heregulin, PDGF-AA and bFGF with T3 for 6 days resulted in repression of O4, O1, Olig2 and PDGFR-α. The OLCs were co-cultured with motoneurons resulted in induction of MOG and MBP, which were expressed in functional OLCs. The latter can be generated from BMSCs-derive NS with high yield.