Effects of Lithium and Lamotrigine on Oxidative–Nitrosative Stress and Spatial Learning Deficit After Global Cerebral Ischemia

Lithium (Li) and lamotrigine (LTG) have neuroprotective properties. However, the exact therapeutic mechanisms of these drugs have not been well understood. We investigated the antioxidant properties of Li (40 and 80 mg/kg/day) and LTG (20 and 40 mg/kg/day) in a rat model of global cerebral ischemia based on permanent bilateral occlusion of the common carotid arteries (BCAO). Nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), glutathione reductase (GSH-R), catalase (CAT) and superoxide dismutase (SOD) levels were measured as an indicator of oxidative–nitrosative stress in both prefrontal cortex (PFC) and hippocampus after 28 days of treatment. The spatial learning disability was also assessed at the end of the study by Morris water maze (MWM) test. All oxidative–nitrosative parameters were found to be higher in the groups under treatment than in sham. Both drugs caused a decrease in PFC NO and MDA elevation, meanwhile the increase in GSH, GSH-R, CAT and SOD levels was significantly more evident in treated groups. We also found higher PFC GSH-R and hippocampal SOD levels in BCAO + Li (80 mg/day) treated group when compared with BCAO + LTG 40 mg/day. MWM test data showed a similar increase in spatial learning ability in all groups under treatment. We found no other statistical difference in comparison of treated groups with different dosages. Our findings suggested that Li and LTG treatments may decrease spatial learning memory deficits accompanied by lower oxidative–nitrosative stress in global cerebral ischemia. Both drugs may have potential benefits for the treatment of vascular dementia in clinical practice.     

Effects of tamoxifen on myocardial ischemia-reperfusion injury model in ovariectomized rats

The purpose of this study is to examine the antiarrhythmic and antioxidant effects of tamoxifen, one of the selective estrogen modulators, in ovariectomized rats subjected to myocardial ischemia-reperfusion (I/R) injury. A month after ovariectomy, rats were divided into four groups: (I) ovariectomized controls without any treatment, (II) ovariectomized rats treated with vehicle dimethylsulfoxide (DMSO), (III)–(IV) ovariectomized rats treated with tamoxifen 1 or 10 mg/kg,sc daily for 14 days. To produce arrhythmia, the left main coronary artery was occluded for 7 min, followed by 7 min of reperfusion. The blood pressure (BP), heart rate (HR), electrocardiography (ECG) was recorded before and during the ischemia-reperfusion period. The blood levels of malondialdehyde (MDA), creatine kinase (CK), glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and catalase (CAT) were measured after the rats were killed. Tamoxifen reduced the incidence of ventricular tachycardia (VT) on ischemia and reperfusion as well as the incidence and duration of reversible ventricular fibrillation (VF) on reperfusion. I/R injury caused a significant fall in GSH, GSH-Px as well as an increase in MDA and CK levels in the control group when compared to tamoxifen treated groups. The changes in levels of CAT and GR were however, not significant. In conclusion, our findings suggest that tamoxifen has cardioprotective effects against I/R injury in rats, likely its antioxidant properties.     

Growth Kinetics of Concave Nanocubes Studied by Optical Coherence Tomography

This work presents the analysis of the growth kinetics of two syntheses of concave gold nanocubes with a mean size of 72 and 108 nm followed by the optical coherence tomography (OCT) technique by acquiring B-scan images each 5 s. In addition, ultra violet-visible (UV-Vis) spectra and mean size from dynamic light scattering (DLS) were acquired during nanoparticle growth to generate kinetic plots in order to corroborate the OCT results. Kinetic plots from OCT images were obtained by plotting contrast enhancement of B-scan images as function of time. Fitting parameters values given by using the classical Kolmogorov-Johnson-Mehl-Avrami (KJMA) equation show that the growth rate parameter k is higher for small cubes than for large ones, and that the Avrami exponent n associated to the growth kinetics of concave nanocubes is close to 2 for both syntheses. The results of UV-Vis spectroscopy and DLS confirm that OCT is a viable technique to provide information about nanoparticle growth kinetics. Moreover, to our knowledge, this is the first time that OCT technique is used to follow nanoparticle growth kinetics.

     

Serum Copper and Zinc Levels in Patients with Endometrial Cancer

Biological Trace Element Research - The aim of the present study was to evaluate serum concentrations of copper (Cu) and zinc (Zn), in relation with metabolic profile and clinicopathologic features...     

Detection of Toxoplasma gondii in cerebrospinal fluid from AIDS patients by nested PCR and rapid identification of type I allele at B1 gene by RFLP analysis

Highly active antiretroviral therapy (HAART) has decreased the incidence of opportunistic infections in the central nervous system (CNS) in AIDS patients. However, toxoplasmic encephalitis (TE) still represents the most common cerebral mass lesion in patients infected with human immunodeficiency virus (HIV). The aim of this study was to evaluate nested PCR-B1 using cerebrospinal fluid (CSF) to detect Toxoplasma gondii DNA for the diagnosis of TE. A total of 114 samples were evaluated, and 33/44 samples from patients with TE were positive by PCR (sensitivity 75%), demonstrating the diagnostic usefulness of PCR technique. PCR-B1 products were analyzed by restriction fragment length polymorphism (RFLP) in 30 samples. Only type I allele at B1 was identified in these samples according banding patterns. This is the first report of evaluation of S1-AS1/S2-AS2 set of primers in more than 100 clinical samples as well as the first genotyping study of T. gondii in Cuba.     

Correlation of serum trace elements and melatonin levels to radiological, biochemical, and histological assessment of degeneration in patients with intervertebral disc herniation

The aim of our study was to assess the blood concentrations of some trace elements and melatonin (MLT) in patients with intervertebral disc herniation (IDH) and to investigate the interaction of histological and biochemical degeneration findings with aging. The present study was carried out on 13 subjects (8 women and 5 men) diagnosed with IDH. They were divided into three groups according to their ages. Nighttime serum MLT, zinc (Zn), and magnesium (Mg) levels were determined in all patients. In addition, computed tomography (CT) scan of the brain and magnetic resonance imaging examination of the lumbar spine were obtained in this study. The Zn level and Zn/Mg ratio showed a decline in patients with IDH with aging, whereas the serum Mg level and tissue hydroxyproline content increased. A positive correlation between serum Zn and MLT concentrations was found (r=0.104, p=0.734). In addition, there was a positive correlation between serum Zn level and Zn/Mg ratio (r=0.835 and p<0.01), and a negative correlation between serum Mg level and Zn/Mg ratio (r=−0.571, p<0.05). On CT study, both volume percentage of calcified pineal gland and density of calcification were found to increase progressively with advancing age. The results of semiquantitative evaluation of disc tissues of patients with IDH for histological degeneration findings showed that 66.7% of discs treated had slight degeneration in younger age group, but 75.0% and 100% of discs had moderate or marked degeneration in older age groups. Our data indicated that there is a close relationship between MLT and Zn or Mg levels in the serum samples of patients with IDH, and the levels of these elements might be affected by the presence of degeneration process and serum MLT level, or vice versa.     

Long-term effects of fire on ant communities (Hymenoptera: Formicidae) in Pinus brutia forests of south-western Turkey

We studied how forest fire affects the structure of ant communities in the long term and how microhabitat variables that influence communities of ants in different succession stages change. For this purpose, we selected five sites burnt 3 to 26 years prior to the study and a control site unburnt for at least 50 years. Sampling of ants was conducted in four pit-fall traps in four transects in three replication plots at every successional site and in two plots at the control site. Microhabitat variables regarding the vegetation structure and litter layers were recorded and related to the abundances of ants. The results show that subshrubs, leaves, and needles were the most important microhabitat variables that affected the ant communities. In certain ant genera, significant changes depending upon successional gradient were determined. While the genera Aphaenogaster and Cataglyphis had non-linear relationships with successional gradient, negative linear relationships were found in Crematogaster and Prenolepis. Messor is the only genus caught in high numbers in the earliest successional stage. It showed a decrease with successional gradient. Significant changes in ant communities along the successional gradient were associated with the characteristics of vegetation and the litter layer.     

Analysis of zinc and magnesium levels in pinealectomized chicks

Melatonin is the main product of the pineal gland, and trace metals play a critical role in growth and development. The purpose of this study was to assess the serum zinc (Zn) and magnesium (Mg) levels in pinealec-tomized chicks and their possible interactions with the development of spinal deformity. Chicks were divided into two equal groups: unoperated controls (group M) and pinealectomized chicks (group N). Pinealectomies were performed at the age of 3 d. After 8 wk, serum Zn and Mg levels of 10 animals from each group were measured by spectrophotometric assay. The results of analyses were compared using the Mann-Whitney U-test. The correlation between serum Zn and Mg levels were assessed by Spearman's correlation. In this study, it was obvious that the serum Zn levels in group N were significantly lower than those in group M (2.8±0.10 vs 4.2±0.14 ppm; p<0.0005). In contrast, Mg levels in group N was high compared with the values in group M, although there was no significant difference (17.8±0.69 vs 15.7±0.85 ppm; p>0.05). In pinealectomized animals, serum Zn levels declined significantly while serum Mg levels increased, albeit insignificantly. Thus, there was a moderately positive but not statistically significant correlation between Mg and Zn levels in unoperated controls (r=0.273, p>0.05), whereas there was a negative but not statistically significant correlation between Zn and Mg levels in pinealectomized chicks (r=−0.115, p>0.05). In addition, the serum Mg to serum Zn ratio was significantly higher in group N than in the group M control (6.39±0.32 vs 3.75±0.22, respectively; p<0.001). From the results of the current study, it is clear that surgical pinealectomy in newly hatched Hybro Broiler chicks has a significant effect on serum Zn level. However, the serum Mg did not change significantly. Because serum Mg is not a good indicator of Mg status in chicks, it is speculated that other tissues, such as muscle or spine, might productively be explored as a more sensitive Mg biomarker for this model. The present study provides experimental evidence that serum trace metal levels might be affected in pinealectomized animals because of the lack of its main neurohormone melatonin.