Octyl and dodecyl gallates induce oxidative stress and apoptosis in a melanoma cell line

This study investigated the mechanism of cytotoxicity of octyl (G8) and dodecyl (G12) gallates in a murine melanoma cell line (B16F10). For this purpose, several methods to measure cell viability were used to determine if the cytotoxicity induced by these gallates corresponds to a general or an organelle-specific effect. Furthermore, the mechanisms related to apoptosis were examined, by studying the caspase-3 activity, oxidative stress, mitochondrial potential and the expression of anti- or proapoptotic proteins. When comparing the various methods of assessing cell viability, the tested gallates showed a higher cytotoxicity in the assay that indicates lysosomal activity, compared with the assays that indicate mitochondrial and ribosomal activities. Both gallates promoted the release of lactate dehydrogenase into the medium, indicating an effect on cell membrane integrity. The gallates also promoted cellular oxidative stress, mitochondrial depolarization and an increase in caspase-3 activity. Furthermore, the gallates induced an increase in proapoptotic (Bax) and a decrease in antiapoptotic (Bcl-2) proteins expression. Our results indicate that the apoptotic cell death induced by G8 and G12 in B16F10 cells involves lipid membrane damages, lysosomal and mitochondrial dysfunction, which was accompanied by alterations in apoptotic proteins expression and seems to be triggered by cellular oxidative stress.     

OPTICAL DENSITY AND CHEMICAL COMPOSITION OF MICROFILLED AND MICROHYBRID COMPOSITE RESINS

This study evaluated the optical density of two microfilled and two microhybrid resins, as well as the composition of these materials with regard to their optical density. Cavities prepared in 12 2-mm- or 4-mm-thick acrylic plastic plates were filled with Z250 (3M-ESPE), A110 (3M-ESPE), Charisma (Heraeus-Kulzer) and DurafillVS (Heraeus-Kulzer). The resin increments (2-mm-thick) were light-cured for 40 s. Three 0.12-s radiographic exposures were made of each #2 acrylic plastic plate. DenOptix system optical plates were used to obtain the digital images. Three readings of the composite resin surface were made in each radiograph, totalizing 216 readings. The mean of highest and lowest grey-scale values was obtained. Two specimens of each composite resin were prepared for SEM analysis of the chemical elements related to optical density, using energy dispersive x-ray analysis (EDX). The results were subjected to Shapiro-Wilk''s test, ANOVA, Tukey''s test at 1% level of significance and Pearson''s correlation. The mean grey-scale values at 2 mm and 4 mm were: Z250 = 154.27a and 185.33w; A110 = 46.77b and 63.05y; Charisma = 163.40c and 200.46z; DurafillVS = 43.92b and 58.99x, respectively. Pearson''s test did not show any positive correlation between optical density and percentage weight of optical density chemical elements. It was concluded that the microhybrid resins had higher optical density means than the microfilled resins; among the evaluated resins, Charisma had the highest optical density means.     

Urinary monocyte chemoattractant protein-1 correlates with disease activity in lupus nephritis

Monocyte chemoattractant protein-1 (MCP-1) has a pathogenic role in murine lupus nephritis (LN). We recruited 25 pediatric and adolescent systemic lupus erythematosus (SLE) patients from our lupus clinic [13 (52%) patients with LN and 12 (48%) lupus non-nephritis patients] and evaluated their urinary and plasma MCP-1 levels compared to adult and childhood controls. The median age and SLE disease duration of patients were 14.4 and 5.5 years, respectively. LN patients had a higher median renal (p?=?0.01) British Isles Lupus Assessment Group (BILAG) index, with a tendency for higher total BILAG scores (p?=?0.2). There were significantly increased urinary MCP-1 levels in the LN patients compared to healthy controls (p?<?0.001) whose values were significantly higher than lupus non-nephritis children (p<?0.004). Urinary MCP-1 levels correlated well with total BILAG scores (r?=?0.82, p?=?0.04). There were no differences in plasma MCP-1 levels between SLE patient groups and pediatric controls, although the levels in the childhood controls were elevated compared to those of the adult controls (p?<?0.04). These results provide evidence of increased urinary—but not plasma—MCP-1 levels in children with LN, which correlates well with SLE disease activity as measured by the BILAG index.     

Potent antiviral activity of brequinar against the emerging Cantagalo virus in cell culture

In the present work, the antiviral activity of brequinar (BQR) against the replication of Cantagalo virus was evaluated. BQR is a potent inhibitor of cellular dihydroorotate dehydrogenase, an enzyme of the de novo pyrimidine biosynthetic pathway. Infection in the presence of 0.5 μM BQR reduced virus progeny production by >90%, revealing an EC₅₀ (drug concentration required to inhibit 50% of virus replication) of 0.017 μM. Replication of other orthopoxviruses was also inhibited by BQR at similar levels. In the presence of the drug, virus early proteins accumulated to control levels, whereas late gene expression was severely impaired. This result was confirmed by indirect immunofluorescence assays and analysis of time-regulated expression of a reporter gene under the control of a virus promoter. Both assays revealed nearly 90% inhibition of late gene expression. BQR also blocked virus DNA replication, which accounted for the subsequent inhibition of virus late gene expression. The ablation of virus DNA replication, late gene expression and infectious progeny production was restored to control levels when infected cells were co-treated with uridine (URD) and BQR. These data demonstrated that BQR targeted virus DNA synthesis by depleting the cellular pyrimidine pool, which was bypassed by the salvage pathway when URD was added to the cell cultures.     

Ketamine treatment reverses behavioral and physiological alterations induced by chronic mild stress in rats

Several studies have supported the idea that ionotropic glutamate N-methyl-d-aspartate receptor (NMDA) is an important player in the etiology of psychopathologies, such as anxiety disorders and major depression. Additionally, studies have shown that ketamine induces antidepressant effects in humans as well as in rodents subjected to animal models of depression. In this context, the present study was aimed to evaluate behavioral and physiological effects of acute and chronic administration of ketamine, a NMDA receptor antagonist, in rats exposed to chronic mild stress (CMS). After 40 days of CMS, rats were treated with ketamine (15 mg/kg) and sweet food consumption, body and adrenal gland weight, corticosterone and adrenocorticotropic (ACTH) hormone levels, and hippocampal BDNF protein levels were assessed. Our findings demonstrated that CMS evoked anhedonia, induced hypertrophy of adrenal gland, impaired gain of body weight and increased corticosterone and ACTH circulating levels in rats. Acute and chronic treatment with ketamine reversed the increase in adrenal gland weight, promoted regain of body weight, and normalized corticosterone and ACTH circulating levels. Repeated, but not acute, administration of ketamine reversed anhedonia-like behavior, although the treatment with ketamine per se increased sweet food consumption in non-stressed rats. Finally, acute and chronic ketamine treatment did not alter hippocampal BDNF protein levels in stressed rats. In conclusion, these findings support the idea of a putative role of NMDA receptors in mood-related symptoms, and rapid and robust effects of ketamine in reverting mainly physiological alterations induced by chronic mild stressful situations in rats.     

Assessment of atrial septal defect size and residual rim using real-time 3D transesophageal echocardiography

Background

Accurate preoperative determination of defect location and size is important for successful transcatheter closure of atrial septal defects (ASD). Real-time 3D transesophageal echocardiography (3DTEE) has the potential to delineate the shape of ASD in 3D space.

Methods

Full volume and 3D zoom datasets by 3DTEE were acquired in 17 ASD patients. Using quantitative software, maximal/minimal diameter, defect area and residual rim length were measured and compared to the standard 2D measurements.

Results

Real-time 3DTEE allowed delineation of the en-face view of the ASDs. The defect typically had an oval shape, and its size changed dynamically, having its minimal size at end-diastole and maximal at end-systole. A good correlation was noted between the maximal defect area by 3DTEE and 2DTEE (r = 0.93, p < 0.001). Successful delineation of rim length to the specific cardiac structure was 100% by 3DTEE and 88% by 2DTEE. There was a fair correlation of residual rim length between 3DTEE and 2DTEE (r = 0.69, p < 0.001). Eight patients underwent transcatheter closure of the ASD. Excellent correlation was noted between 3D-derived maximal defect diameter and device diameter (r = 0.97, p < 0.001).

Conclusions

Real-time 3DTEE allows measurements of the temporal and spatial changes of ASD size and shape. This methodology provides detailed information on defect dynamics.