Formation of functional nanobiocatalysts with a novel and encouraging immobilization approach and their versatile bioanalytical applications

The discovery of functional organic–inorganic hybrid nanoflowers (FNFs) consisting of proteins/enzymes as the organic components and Cu(ii) ion as the inorganic component has made an enormous impact on enzyme immobilization studies. The FNFs synthesized by an encouraging and novel approach not only showed high stabilities but also much enhanced catalytic activities as compared to free and conventionally immobilized enzymes. A recent development demonstrated that FNF formation has moved beyond the initial discovery in which enzymes and Cu²⁺ ions used as the organic and inorganic parts, respectively, are replaced with new organic (chitosan, amino acid and plant extracts) and inorganic (Cu²⁺ and Fe²⁺) materials. The new organic materials incorporated into FNFs act as Fenton-like agents and then show peroxidase-like activity owing to the metal ions and the porous structure of FNFs in the presence of hydrogen peroxide (H₂O₂). All FNFs have been widely utilized in many different scientific and industrial fields due to their greatly enhanced activities and stabilities. This review focuses primarily on the preparation, characterization, and bioanalytical applications of FNFs and explains the mechanisms of their formation and enhanced activities and stabilities.

The discovery of functional organic–inorganic hybrid nanoflowers (FNFs) consisting of proteins/enzymes as the organic components and Cu(ii) ion as the inorganic component has made an enormous impact on enzyme immobilization studies.     

Cofactor metals and antioxidant enzymes in cisplatin-treated rats: effect of antioxidant intervention

We explored the association between the activities of antioxidant enzymes and their metallic cofactors in rats treated with cisplatin. The antioxidant effects of aminoguanidine, and a combination of vitamins E and C were investigated. Plasma platin was significantly lower than liver and kidney. Cisplatin treatment caused significant increase in plasma Se-glutathione peroxidase activity. Activities of Se-glutathione peroxidase, glutathione S-transferase, catalase and Cu,Zn-superoxide dismutase have been found to be significantly decreased in liver and kidney compared to controls. Zn levels in these organs were diminished upon cisplatin treatment, while levels of Cu were unaffected. Interestingly, levels of iron, the cofactor of catalase, were found to be significantly increased in liver and kidney. Intervention with aminoguanidine or vitamins was generally prevented cisplatin-caused changes in the activity of enzymes and in the tissue levels of cofactor metals. These observations suggest that relation between activities of enzymes and levels of cofactor metals is multifactorial.     

Evaluation of effects of T and N type calcium channel blockers on the electroencephalogram recordings in Wistar Albino Glaxo/Rij rats,an absence epilepsy model

Objectives:It is suggested that excessive calcium entry into neurons is the main triggering event in the initiation of epileptic discharges. We aimed to investigate the role of T and N type calcium channels in absence epilepsy experimental model.Results:Beta and delta recording ratios in 1 μM/5 μl mibefradil group was significantly different from basal and other dose-injected groups. Beta, alpha, and theta recordings in 0.2 μM/5 μl w-Conotoxin MVIIA group was significantly different from basal and other dose-injected groups. In w-Conotoxin MVIIA after mibefradil group, beta, alpha, and theta recording ratios were significantly different from basal and mibefradil group. Mibefradil and w-Conotoxin MVIIA significantly decreased the frequency and duration of SWDs. The decrease of frequency and duration of SWDs in mibefradil group was significantly different from w-Conotoxin MVIIA group. The frequency and duration of SWDs significantly decreased in w-Conotoxin MVIIA after mibefradil group compared with basal, mibefradil, and w-Conotoxin MVIIA groups.Conclusions:We concluded that both T and L type calcium channels play activator roles in SWDs and have positive effects on frequency and duration of these discharges. These results are related with their central effects more than peripheral effects.KEY WORDS: Epilepsy, mibefradil, T and N type calcium channels, Wistar Albino Glaxo/Rij rats, w-Conotoxin MVIIA     

Acromegaly is associated with a distinct oral and gut microbiota

Pituitary - Our aim was to investigate the changes in the composition of oral and gut microbiota in patients with newly diagnosed acromegaly and their relationship with IGF-1 levels. Oral and fecal...     

Sleep quality and related factors including restless leg syndrome in medical students and residents in a Turkish university

Sleep and Breathing - The aim was to determine sleep quality and related factors including restless leg syndrome in the 6th year medical students and medical residents in Pamukkale University,...     

Elevated carbohydrate antigen 19-9 levels in a patient with choledocholithiasis.

Carbohydrate antigen 19-9 (CA19-9) has been used as a tumor marker in the diagnosis and differentiation of pancreatic cancers. However, significantly high levels of CA 19-9 in the absence of pancreatic malignancy have also been reported. We present a 50-year-old woman with a common bile duct stone and cholangitis, whose CA 19-9 level of 1.500 U/ml returned to normal after definitive treatment of choledocholithiasis.     

Levels of soluble E-selectin in patients with active Behçet’s disease

Behçets disease is a systemic vasculitis of unknown aetiology. Endothelial cell injury plays an important role in the pathogenesis and immunopathology of Behçets disease. E-selectin is expressed by activated endothelial cells. Because the selectin adhesion molecules are shed from activated cells, soluble forms of these proteins can be used as activation markers of endothelium (E-selectin). The pathogenesis of Behçets disease (BD) is closely related to endothelial cells, leucocyte functions and immunity. The aim of this study was to investigate circulating E-selectin adhesion molecules, which are known to play a significant part in the immune response especially by regulating interaction of the leucocytes with endothelium in BD. Plasma E-selectin concentrations were evaluated in 23 patients with BD and 20 healthy control subjects. The disease activity was evaluated by clinical manifestations (oral aphthous ulcer, genital ulceration, positive pathergy test, skin lesions, eye involvement, thrombophlebitis and arthritis) and by laboratory investigations [erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)]. The patients were newly or previously diagnosed cases not taking any drug for BD. Levels of E-selectin were measured with commercially available sandwich enzyme-linked immunosorbent assay (ELISA) kits using human sE-selectin (cat. no: BMS 205). Plasma E-selectin concentrations of patients and controls were compared with the Mann-Whitney U test. Statistical significance was assigned to p values lower than 0.05. Serum levels (mean±SD) of soluble E-selectin (sE-selectin) were significantly higher in 23 patients with BD than in 20 healthy controls (53.2±18.2 ng/ml vs 33.8±7.5 ng/ml, p<0.0001). A statistically significant positive correlation was observed between sE-selectin levels and CRP and ESR in patients with BD (r=0.78, p<0.001 and r=0.56, p<0.01, respectively). Increases in the E-selectin in BD may be a direct consequence of the leucocyte and endothelium activations observed during the disease process. The noninvasive investigations can be used as biochemical markers for inflammation. This may provide additional information regarding disease activity along with the traditional indices such as ESR and CRP.     

Hemoperitoneum secondary to spontaneous rupture of metastatic gastric leiomyosarcoma of the liver: Report of a case.

Hepatic rupture with resulting hemoperitoneum due to metastatic cancer is uncommon. Reports in the literature have described a wide variety of neoplasms causing this usually fatal phenomenon. We describe a rare case of spontaneous rupture of hepatic metastases from gastric leiomyosarcoma. A 72-year-old male patient with sudden onset severe epigastric pain was rushed into emergency service. After examination, the patient underwent urgent operation withe possible diagnosis of perforated gastric or duodenal ulcer. During exploration, we determined bleeding mass on the diaphragmatic side of the left lobe of the liver and a mass on the posterior wall of the stomach. Hemostasis was provided.