Prostaglandin-mediated effects in early canine corpus luteum: In vivo effects on vascular and immune factors

Prostaglandins (PGs) are important regulators of the early corpus luteum (CL) in the dog. Whereas, initially, CL is gonadotropin independent, in the second half of its lifespan, hypophyseal support is required. The transition period is marked by decreased availability of PGs, in particular of PGE2. We previously reported that inhibition of COX2/PTGS2 in vivo suppressed luteal production of PGE2, lowered circulating progesterone and negatively affected luteal development. Therefore, bitches were treated with a COX2-specific blocker, firocoxib, for 5, 10, 20 and 30 days after ovulation, leading to suppression of the steroidogenic machinery. Control groups received a placebo for the same periods. Considering the wide range of possible modulatory roles of PGs shown in different organ systems, this follow-up project aimed to understand further possible PG-mediated effects in early canine CL. Thirty-four (34) factors related predominantly to vascularization and immune response were screened (mRNAs and proteins) on samples from the above described in vivo study. Most of the effects were observed during the transitional period (days 20 and 30). The inhibition of COX2 diminished the expression of angiopoietin family members ANGPT1, -2, Tie1 and -2 receptors. The expression of endothelin (ET)-1 was increased. Concerning the immune system, increased expression of the pro-inflammatory cytokines, IL1β, IL6 and IL12a, and elevated expression levels of CD4, was observed. Cumulatively, besides its involvement in regulating steroidogenesis, our results indicate a broader role of PGs in the canine CL, including modulation of angiogenesis, vascular stabilization and local immunomodulation. Possible cross-species translational effects are strongly implied.     

Removal of cadmium by Pleurotus sajor-caju basidiomycetes

The bioaccumulation of cadmium by the white rot fungus Pleurotus sajor-caju onto dry biomass was investigated using aqueous media with concentrations in the range of 0.125 mM–1.0 mM The highest cadmium uptake (between 88.9 and 91.8%) was observed with aerobic fungal biomass from the exponential growth phase. Up to 1.0 mM cadmium gradually inhibited mycelium development, but never blocked it completely. Freeze-dried, oven-dried and non-metabolizing live Pleurotus sajor-caju biomass types were tested for their capacity to adsorb the test ion Cd²⁺ within the pH range of 4.5 to 6.0. Freeze–dried biomass proved to be the most efficient biomass type for Cd²⁺ metal adsorption. Therefore, Pleurotus sajor-caju may be used for heavy metal removal and bioremediation.     

A Silver Compound with Potential Applications as an Anticancer,Antibacterial, Antifungal,and Anti-Alzheimer's Agent

This study investigated the biological activity of the silver coordination compound K-22. The IC₅₀ values of K-22 on cancer cell lines range from 0.797 μg/mL to 3.426 μg/mL, indicating that K-22 might preferably inhibit A549, Saos-2, MCF-7, and HT-29 cell proliferation and thus have better therapeutic activity. Furthermore, K-22 stimulated apoptosis via up-regulation of the mRNA and protein expression level of Bax/Bcl-2 ratio in A549, Saos-2, MCF-7, and HT-29. K-22 exhibited antimicrobial activity against S. aureus, E. faecalis, K. pneumonia, P. aeruginosa, C. utilis, and C. albicans. Experimental results show that the compound has inhibitory potential with an IC₅₀ value of 178.10 μM for the BChE (butyrylcholinesterase) enzyme, which has a vital role in the progression of Alzheimer's disease. As a result, compound K-22 exhibits a strong potential for medical use due to its anticancer, antibacterial, antifungal, and anti-Alzheimer properties.     

The partial purification and properties of pepsin obtained from Turkey proventriculus

In this study, pepsin from turkey proventriculus was purified, and its biochemical properties examined. Initially, the turkey proventriculus (stomach) was mixed with 10% NaCl (1∶2, w/v) and extracted by centrifugation to produce a crude extract. The partial purification of the extract was carried out using Sephadex G-50 resin in gel filtration column chromatography. The fractions obtained by gel filtration were analyzed for milk clotting activity (MCA), protein content, proteolytic activity (PA), purification factor (PF), and SDS-PAGE electrophoresis was also performed. The enzyme was purified 207-fold with a recovery of 36%. The first 4 fractions did not have any activities; fractions 7, 8, and 9 exhibited the highest levels of milk clotting and proteolytic activity. The electrophoretic patterns revealed that further purification steps should be applied for better results.     

The alterations of leukotriene C4 and prostaglandin E2 levels following different ischemic periods in rat brain tissue

Leukotrienes and prostaglandins are formed from arachidonic acid by activation of local phospholipases in pathological conditions such as cerebral ischemia, subarachnoid hemorrhage, cerebral tumors and seizures. These mediators, especially leukotrienes have a very potent vasoconstrictor effect on cerebral arteries. Experimental studies have shown that this effect, by increasing vascular permeability causes vasogenic edema that contributes to the ischemic penumbra. In this study, after developing an experimental animal model simulating the concept of ischemic penumbra in the rat, the levels of leukotriene C and prostaglandin E2 produced in the forebrain were measured and the effects of these mediators in prolonged ischemia were investigated. The results, in the first 4 min of ischemia, showed that the arachidonic acid metabolites, particularly, leukotriene C4, reached a peak in the ischemic cerebral tissue in association with leukocyte accumulation. Later in the 15th min, significant decreases in leukotriene C4 and prostaglandin E2 levels were seen. In the 1st and 4th h, probably due to the stimulation of the relevant enzymes by free oxygen radicals in the ischemic tissue; the levels increase again, returning to control values by the 12th h. It is concluded that the use of lipoxygenase inhibitors and free radical scavengers may be helpful to limit the infarct area in the first 4 h of ischemia.     

Genomic analysis to screen potential genes and mutations in children with non-syndromic early onset severe obesity: a multicentre study in Turkey

Molecular Biology Reports - Obesity is a complex genetic-based pediatric disorder which triggers life-threatening conditions. Therefore, the understanding the molecular mechanisms of obesity has...     

Elaborate ultrastructure of the Hirudo (Annelida: Hirudinae) cocoon surface

Species of medicinal leeches (Hirudo medicinalis, H. verbana, and H. sulukii) secrete hard‐shelled cocoons. When initially deposited, a cocoon is surrounded by a foam. Over a short time, the foam is transformed into a three‐dimensional structure. We show here that this peripheral structure likely forms by the solidification and dehydration of a moderately viscous, proteinaceous substance that surrounds bubbles of various sizes. The resulting matrix‐like structure comprises a network of curved branches juxtaposed at ～120° and taper in width as a function of distance from the outer cocoon wall. The material is proteinaceous, and traps environmental material in its composition, especially silicon. The geometry of compartments and abundance of silicon on branch surfaces suggest a mechanism for trapping water to prevent desiccation in a terrestrial environment.