In vitro inhibition of cytosolic carbonic anhydrases I and II by some new dihydroxycoumarin compounds

A new series of 6, 7-dihydroxy-3-(methylphenyl) chromenones, including three new derivatives, i.e. 6,7-dihydroxy-3-(2-methylphenyl)-2H-chromen-2-one (OPC); 6,7-dihydroxy-3-(3-methylphenyl)-2H-chromen-2-one (MPC); 6,7-dihydroxy-3-(4-methylphenyl)-2H-chromen-2-one (PPC) and one previously described, namely 6,7-dihydroxy-3-phenyl-2H-chromen-2-one (DPC), were synthesized. These compounds were investigated as inhibitors of human carbonic anhydrase I (hCA-I) and human carbonic anhydrase II (hCA-II) which had been purified from human erythrocytes on an affinity gel comprised of L-tyrosine-sulfonamide-Sepharose 4B.     

Efficient Pre-mRNA Cleavage Prevents Replication-Stress-Associated Genome Instability

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Immobilization of catalase via adsorption onto -histidine grafted functional pHEMA based membrane

Poly(2-hydroxyethylmethacrylate) (pHEMA) based flat sheet membrane was prepared by UV-initiated photopolymerization technique. The membrane was then grafted with -histidine. Catalase immobilization onto the membrane from aqueous solutions containing different amounts of catalase at different pH was investigated in a batch system. The maximum catalase immobilization capacity of the pHEMA–histidine membrane was 86 μg cm⁻². The activity yield was decreased with the increase of the enzyme loading. It was observed that there was a significant change between V_max value of the free catalase and V_max value of the adsorbed catalase on the pHEMA–histidine membrane. The K_m value of the immobilized enzyme was higher 1.5 times than that of the free enzyme. Optimum operational temperature was 5°C higher than that of the free enzyme and was significantly broader. It was observed that enzyme could be repeatedly adsorbed and desorbed without loss of adsorption capacity or enzyme activity.     

Investigation of Oxidative Status of the 2-Furan-2-yl-1H-Benzimidazole in Rats

We investigated the influence of 2-furan-2-yl-1H-benzimidazole regarding vitamins A, E, C, selenium (Se), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) levels on rats. 2-Furan-2-yl-1H-benzimidazole was given to rats by subcutaneous injection every other day for a total of 22 injections. At the end of the experiment, Se levels were determined by using a fluorimetric method. Serum levels of vitamins A, E, C, and malondialdehyde (MDA) were determined by high-performance liquid chromatography. Glutathione peroxidase (GSH-Px) levels of erythrocytes were spectrophotometrically determined. Our experimental results showed that vitamins A, E, C, and Se levels were found generally lower than the control groups, while serum MDA level and GSH-Px activity flexibly increased, which is dependent on injection days. The observed decreases in vitamins A, E, C, and Se levels in the blood might be causally related to the increased amount of free radicals that are generated with 2-furan-2-yl-1H-benzimidazole injection. However, further investigations are needed to clarify the significance of this observation in respect with the 2-furan-2-yl-1H-benzimidazole injection.     

A new species of the genus Vulda Jacquelin du Val from Turkey (Coleoptera: Staphylinidae: Xantholinini)

Vulda assingi sp. n. from Bozda?lar, Manisa province, western Anatolia, is de-scribed, illustrated and distinguished from congeners recorded from Turkey. Additional records are reported for two species. A total of six species is now known from Turkey.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:B3E6C251-50D4-4985-9655-2EAC57869F18     

Effects of pinealectomy and exogenous melatonin on ghrelin and peptide YY in gastrointestinal system and neuropeptide Y in hypothalamic arcuate nucleus: immunohistochemical studies in male rats

It is reported that the pineal gland and its main hormone melatonin may have a role in the regulation of ghrelin synthesis in the brain. Stomach is the place where ghrelin is predominantly expressed and secreted. One aim of this study was to investigate possible effects of pinealectomy and melatonin treatment on gastric ghrelin amount. The studies on the effects of the pineal gland on leptin and ghrelin arises the question whether the pineal gland has also effects on the other energy-regulatory peptides such as peptide YY (PYY) and neuropeptide Y (NPY). Therefore, we also aimed to investigate the changes in the immunohistochemical staining of intestinal PYY and hypothalamic NPY following pinealectomy and melatonin treatment. Serum PYY levels were also investigated. Sprague-Dawley rats were divided into four groups as sham-operated (SHAM), sham-operated with melatonin treatment (SHAM-MT), pinealectomised (PNX) and melatonin-treated PNX (PNX-MT) groups. The cells immunostained for ghrelin were abundant throughout the gastric mucosa in all the groups. Neither pinealectomy nor exogenous melatonin affected significantly immunohistochemical staining of ghrelin in stomach. Pinealectomy resulted in a significant increase in immunohistochemical staining of PYY in ileum. The results of serum PYY measurement corresponded closely to the data obtained by immunohistochemical analysis of PYY in ileum, being significantly lower and higher in SHAM and PNX groups, respectively. Pinealectomy caused a decrease in NPY synthesis in ARC as understood from low immunohistochemical staining of NPY. Melatonin treatment increased NPY synthesis in SHAM rats and restored reduction in NPY synthesis caused by pinealectomy. In conclusion, the pineal gland and its main hormone melatonin can be suggested to have a role in the regulation of NPY synthesis in ARC and PYY in gastrointestinal system.     

Efficiency considerations for the purely tapered interference fit (TIF) abutments used in dental implants

A tapered interference fit provides a mechanically reliable retention mechanism for the implant-abutment interface in a dental implant. Understanding the mechanical properties of the tapered interface with or without a screw at the bottom has been the subject of a considerable amount of studies involving experiments and finite element (FE) analysis. In this paper, approximate closed-form formulas are developed to analyze the mechanics of a tapered interference fit. In particular, the insertion force, the efficiency, defined as the ratio of the pull-out force to insertion force, and the critical insertion depth, which causes the onset of plastic deformation, are analyzed. It is shown that the insertion force is a function of the taper angle, the contact length, the inner and outer radii of the implant, the static and the kinetic coefficients of friction, and the elastic modulii of the implant/abutment materials. The efficiency of the tapered interference fit, which is defined as the ratio of the pull-out force to insertion force, is found to be greater than one, for taper angles that are less than 6 deg when the friction coefficient is 0.3. A safe range of insertion forces has been shown to exist. The lower end of this range depends on the maximum pull-out force that may occur due to occlusion in the multiple tooth restorations and the efficiency of the system; and the upper end of this range depends on the plastic deformation of the abutment and the implant due to interference fit. It has been shown that using a small taper angle and a long contact length widens the safe range of insertion forces.     

Serum interleukin-18 and nitric oxide activity in bladder carcinoma

BACKGROUND: Both interleukin-18 and nitric oxide are multifunctional molecules that are involved in the different steps of carcinogenesis. METHODS: In the present study, we measured serum interleukin-18 and nitric oxide activity in 51 bladder cancer patients with different tumor stage and grade, and in 8 healthy controls. Serum nitrite-nitrate levels were measured as an index of nitric oxide generation. RESULTS: Serum interleukin-18 levels were significantly higher in bladder cancer patients when compared to the control subjects (p > 0.05). Serum interleukin-18 levels were found to be higher in patients with Ta stage than patients with T1 and T2, T3, T4 stages and in patients with grade 1 tumors than patients with grade 2 and grade 3 tumors, but this was not statistically significant (p > 0.05). There was no significant difference in serum nitrite + nitrate levels between bladder cancer patients and control subjects. CONCLUSIONS: Elevated serum interleukin-18 levels in bladder carcinoma patients may be a result of host defence mechanism against the growth and progression of bladder cancer cells.     

AHNAK controls 53BP1-mediated p53 response by restraining 53BP1 oligomerization and phase separation

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