The protective effect of arbutin against potassium bromate-induced oxidative damage in the rat brain

This study aimed to investigate the protective effects of arbutin (ARB) against brain injury induced in rats with potassium bromate (KBrO₃). The rats were divided into four groups as Group 1: Control (0.9% NaCl ml/kg/day p.), Group 2: KBrO₃ (100 mg/kg (gavage), Group 3: ARB (50 mg/kg/day p.), and Group 4: KBrO₃ + ARB (100 mg/kg (gavage) + 50 mg/kg/day p.). At the end of the fifth day of the study, the rats in all groups were killed, and their brain tissues were collected. In the collected brain tissues, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels were measured, and routine histopathological examinations were made. The MDA levels in the group that was exposed to KBrO₃ were significantly higher than those in the control group (p ˂ 0.001). In comparison to the KBrO₃ group, the MDA levels in the KBrO₃ + ARB group were significantly lower (p ˂ 0.001). It was observed that SOD and CAT enzyme activity levels were significantly lower in the KBrO₃ group compared to the control group (p ˂ 0.001), while these levels were significantly higher in the KBrO₃ + ARB group than in the KBrO₃ group (p ˂ 0.001). Additionally, the group that was subjected to KBrO₃ toxicity, as well as ARB administration, had much lower levels of histopathologic signs than the group that was subjected to KBrO₃ toxicity only. Consequently, it was found that KBrO₃ exposure led to injury in the brain tissues of the rats, and using ARB was effective in preventing this injury.     

Combinatorial materials research applied to the development of new surface coatings IV. A high-throughput bacterial biofilm retention and retraction assay for screening fouling-release performance of coatings

Abstract

A high-throughput bacterial biofilm retention screening method has been augmented to facilitate the rapid analysis and down-selection of fouling-release coatings for identification of promising candidates. Coatings were cast in modified 24-well tissue culture plates and inoculated with the marine bacterium Cytophaga lytica for attachment and biofilm growth. Biofilms retained after rinsing with deionised water were dried at ambient laboratory conditions. During the drying process, retained biofilms retracted through a surface de-wetting phenomenon on the hydrophobic silicone surfaces. The retracted biofilms were stained with crystal violet, imaged, and analysed for percentage coverage. Two sets of experimental fouling-release coatings were analysed with the high-throughput biofilm retention and retraction assay (HTBRRA). The first set consisted of a series of model polysiloxane coatings that were systematically varied with respect to ratios of low and high MW silanol-terminated PDMS, level of cross-linker, and amount of silicone oil. The second set consisted of cross-linked PDMS-polyurethane coatings varied with respect to the MW of the PDMS and end group functionality. For the model polysiloxane coatings, HTBRRA results were compared to data obtained from field immersion testing at the Indian River Lagoon at the Florida Institute of Technology. The percentage coverage calculations of retracted biofilms correlated well to barnacle adhesion strength in the field (R² = 0.82) and accurately identified the best and poorest performing coating compositions. For the cross-linked PDMS-polyurethane coatings, the HTBRRA results were compared to combinatorial pseudobarnacle pull-off adhesion data and good agreement in performance was observed. Details of the developed assay and its implications in the rapid discovery of new fouling-release coatings are discussed.     

Role of vascularization in determining the time of hypoxic-ischemic encephalopathy in the neonate

OBJECTIVE: To examine the role of vascularization in determining the time of hypoxic-ischemic encephalopathy (HIEP). STUDY DESIGN: Brain sections of 126 neonatal autopsy cases were examined for edema, gliosis, congestion, inflammation and ischemia. Capillary vessels were examined with both reticulum stains and antibody against CD34. Vascular surface density (VSD) and number of vessels per stroma (NVES) were calculated by stereologic methods. RESULTS: Among 126 cases, 64 were male (50.8%) and 62 female (49.2%). In 25 cases HIEP was observed; 14 had a pregnancy history of hypertension, eclampsia or diabetes mellitus in the mother, with fetal distress or underdeveloped features. Statistically, NVES was strongly related to primary HIEP. However, the HIEP and non-HIEP cases revealed no differences in NVES and VSD means. CONCLUSION: Vascularization, especially NVES, helps in determining whether an HIEP case is pregnancy related or due to end-stage changes of dying, but is not an indicator of HIEP.     

Intercostal variation for age estimation--are the standards for the right 4th rib applicable for other ribs?

Age estimation of unknown skeletal remains is very important in forensic medicine. Morphologic methods are fast and easy to use for purpose of age determination. The sternal ends of the ribs are a reliable method of age estimation from late adolescence to old age. Iscan et al developed a phase analysis method for the right 4th rib that was sex and race specific. The purpose of this study is to determine the accuracy of the standards of age estimation from the right 4th and other rib using the phase analysis for the Turkish population. The sample consisted of right and left 3rd, 4th and 5th ribs from 34 Turkish women and 76 men. There were statistically significant variations found on the right 5th, left 3rd, 4th, and 5th ribs according to these standards in men for phases 5, 6, and 7. For women, all the right and left ribs included in this study were in concordance with right 4th rib standards in all phases.     

Homology and Evolution of the Chaetae in Echiura (Annelida)

Echiura is traditionally regarded as a small phylum of unsegmented spiralian worms. Molecular analyses, however, provide unquestionable evidence that Echiura are derived annelids that lost segmentation. Like annelids, echiurans possess chaetae, a single ventral pair in all species and one or two additional caudal hemi-circles of chaetae in two subgroups, but their evolutionary origin and affiliation to annelid chaetae are unresolved. Since annelids possess segmental pairs of dorsal (notopodial) and ventral (neuropodial) chaetae that are arranged in a row, the ventral chaetae in Echiura either represent a single or a paired neuropodial group of chaetae, while the caudal circle may represent fused rows of chaetae. In annelids, chaetogenesis is generally restricted to the ventral part of the notopodial chaetal sac and to the dorsal part of the neuropodial chaetal sac. We used the exact position of the chaetal formation site in the echiuran species, Thalassema thalassemum (Pallas, 1766) and Echiurus echiurus (Pallas, 1767), to test different hypotheses of the evolution of echiurid chaetae. As in annelids, a single chaetoblast is responsible for chaetogenesis in both species. Each chaeta of the ventral pair arises from its own chaetal sac and possesses a lateral formation site, evidencing that the pair of ventral chaetae in Echiura is homologous to a pair of neuropodia that fused on the ventral side, while the notopodia were reduced. Both caudal hemi-circles of chaetae in Echiurus echiurus are composed of several individual chaetal sacs, each with its own formative site. This finding argues against a homology of these hemi-circles of chaetae and annelids’ rows of chaetae and leads to the hypothesis that the caudal chaetal rings evolved once within the Echiura by multiplication of ventral chaetae.     

Levels of some trace elements and rheumatoid factor in sheep with brucellosis

Brucellosis is a zoonotic disease that is encountered in sheep rather frequently. In this study, 100 sheep diagnosed with brucellosis that had aborts and 40 healthy sheep were used as materials. Analyses for Cu, Zn, Fe, Cr, Ca, Mg, and K were performed with the atomic absorption spectrophotometric method on blood collected from vena jugularis of all the sheep and rheumatoid factor levels were determined by the nephelometry method. Although it was found that Cu, Ca, and rheumatoid factor values in the sera of the sheep with brucellosis were high when compared to the control group (p<0.001, p<0.05, p<0.001, respectively), their serum Zn values were low (p<0.05). No significant changes in serum Cr, Fe, K, and Mg levels were found.     

Structure of anticancer ruthenium half-sandwich complex bound to glycogen synthase kinase 3β

The 3.15-Å-resolution crystal structure of the R enantiomer of the highly bioactive and antiproliferative half-sandwich ruthenium complex DW12 bound to the ATP binding site of glycogen synthase kinase 3β (GSK-3β) is reported and the binding is compared with the GSK-3β binding of staurosporine and other organic inhibitors. The structure reveals a close packing of the organometallic inhibitor in the ATP binding site of GSK-3β via an induced-fit mechanism. The molecular structure of (R)-DW12 with the CO ligand oriented perpendicular to the pyridocarbazole heterocycle allows the complex to stretch the whole distance sandwiched between the faces of the N- and C-terminal lobes and to interact tightly with the flexible glycine-rich loop, which is uncommon for the interaction of GSK-3β with organic inhibitors.     

Trace Element Status of Chronic Renal Patients Undergoing Hemodialysis

The purpose of this study was to examine the status of trace elements (Cu, Zn, and Fe) and minerals (Mg, K, Na, and Cl) and the level of biochemical parameters (urea, creatinine, total protein, albumin, and glucose) in hemodialysis (HD) patients. This study included 30 HD patients (25 men and 5 women) aged 52.12 +/- 3.13 years and 30 healthy subjects (23 men and 7 women) aged 51.64 +/- 2.22 years. This study investigated the status of trace elements and minerals in HD patients. It was found that the total HD patients (before and after dialysis) had statistically lower Zn and albumin in the after-dialysis group K and Cl levels and higher Mg, creatinine, and urea in the before-dialysis group K and in the after-dialysis group glucose levels than those of the controls. It was determined that the results might be helpful in monitoring patients with renal failure in terms of insufficiency or excess of trace elements and minerals. There was positive correlation for Mg-K (r = 0.64; p = 0.001), creatinine-urea (r = 0.59; p = 0.001), K-urea (r = 0.56; p = 0.001), K-creatinine (r = 0.52; p = 0.003), Mg-creatinine (r = 0.47; p = 0.008), Zn-albumin (r = 0.40; p = 0.028), and Zn-creatinine (r = 0.40; p = 0.031) in the before-dialysis session. There was also positive correlation for creatinine-urea (r = 0.56; p = 0.001), K-urea (r = 0.39; p = 0.035), and Mg-creatinine (r = 0.38; p = 0.041) in the after-analysis session. As a result of the analysis of regression between serum levels of albumin and zinc in total HD patients, the use of the level of albumin might be a suitable choice in determining zinc deficiency resulting from the decrease in the level of zinc in parallel to that of albumin. The results also suggest that the relationship between creatinine and K, Mg, and Zn could be ascribed to the loss of renal function.     

Lipids in cell biology: how can we understand them better?

Lipids are a major class of biological molecules and play many key roles in different processes. The diversity of lipids is on the same order of magnitude as that of proteins: cells express tens of thousands of different lipids and hundreds of proteins to regulate their metabolism and transport. Despite their clear importance and essential functions, lipids have not been as well studied as proteins. We discuss here some of the reasons why it has been challenging to study lipids and outline technological developments that are allowing us to begin lifting lipids out of their “Cinderella” status. We focus on recent advances in lipid identification, visualization, and investigation of their biophysics and perturbations and suggest that the field has sufficiently advanced to encourage broader investigation into these intriguing molecules.Lipids are fundamental building blocks of all cells and play many important and varied roles. They are key components of the plasma membrane and other cellular compartments, including the nuclear membrane, the endoplasmic reticulum, the Golgi apparatus, and trafficking vesicles such as endosomes and lysosomes. The lipid composition of different organelles, cell types, and ultimately tissues can vary substantially, suggesting that different lipids are required for different functions (Saghatelian et al., 2006 ; Klose et al., 2013 ). Mammalian cells express tens of thousands of different lipid species and use hundreds of proteins to synthesize, metabolize, and transport them. Although the complexity and diversity of lipids approach those of proteins, we have a much poorer understanding of their functions, making lipids in many ways the “Cinderellas” of cell biology. We discuss here recent advances, and challenges, in investigating how these molecules contribute to the many biological processes in which they participate.Like proteins, lipids can have structural (e.g., by stabilizing different membrane curvatures) or signaling roles. Posttranslational lipidation of proteins (e.g., palmitoylation or farnesylation) and carbohydrate-linked lipids (glycolipids) are also important examples of cellular lipid pools. It is clear that higher-order organization is key to most lipid functions, and they are believed to assemble into signaling platforms that contain both lipids and proteins (Kusumi et al., 2012 ). Some lipid microdomains are termed lipid rafts, and much ongoing effort is being focused on defining their parameters (Simons and Sampaio, 2011 ; Suzuki et al., 2012 ; Klotzsch and Schutz, 2013 ). Because of this focus on lipid rafts, we have a better understanding of the properties of proposed raft lipids (e.g., sphingomyelins and cholesterol) than of many other lipid species. Much of what we know about lipids has come from studying synthetic membranes with specific lipid compositions. Although model membranes usually consist of very few (<10) lipid species, they have been useful for understanding the biophysical properties of lipids. At the other end of the spectrum, lipids have been implicated in various diseases, with cholesterol metabolism being a prominent example. We are now getting to a point at which we can address the roles of lipids in the middle of the spectrum—in cells.