Antihypertensive effect of non-diuretic doses of cicletanine on a stress-induced model in the rat

Cicletanine was tested at different doses (7.5, 10 and 30 mg/kg, p.o.) on young rats showing high blood pressure readings after social deprivation for 7 consecutive days. At all dose levels, the compound produced a statistically significant decrease in systolic blood pressure of isolated but not group-housed rats. In contrast, the drug did not affect the heart rate in any of the cases. Interestingly, cicletanine was only found to enhance urinary excretion at the highest dose assayed. The putative mechanism of the antihypertensive action of the drug at non-diuretic doses is discussed.     

Automatic detection of carotid arteries in computed tomography angiography: a proof of concept protocol

Atherosclerosis is one of the leading causes of mortality in the western world. Computed tomography angiography (CTA) is the conventional imaging method used for pre-surgery assessment of the blood flow within the carotid vessel. In this paper, we present a proof of concept of a novel, fast and operator independent protocol for the automatic detection (seeding) of the carotid arteries in CTA in the thorax and upper neck region. The dataset is composed of 14 patients’ CTA images of the neck region. The performance of this method is compared with manual seeding by four trained operators. Inter-operator variation is also assessed based on the dataset. The minimum, average and maximum coefficient of variation among the operators was (0, 2, 5?%), respectively. The performance of our method is comparable with the state of the art alternative, presenting a detection rate of 75 and 71?% for the lowest and uppermost image levels, respectively. The mean processing time is 167 s per patient versus 386 s for manual seeding. There are no significant differences between the manual and automatic seed positions in the volumes (p?=?0.29). A fast, operator independent protocol was developed for the automatic detection of carotid arteries in CTA. The results are encouraging and provide the basis for the creation of automatic detection and analysis tools for carotid arteries.     

Poly (ADP-ribose) polymerase 3 (PARP3), a potential repressor of telomerase activity

Background

Considering previous result in Non-Small Cell Lung Cancer (NSCLC), we investigated in human cancer cells the role of PARP3 in the regulation of telomerase activity.

Methods

We selected A549 (lung adenocarcinoma cell line) and Saos-2 (osteosarcoma cell line), with high and low telomerase activity levels, respectively. The first one was transfected using a plasmid construction containing a PARP3 sequence, whereas the Saos-2 cells were submitted to shRNA transfection to get PARP3 depletion. PARP3 expression on both cell systems was evaluated by real-time quantitative PCR and PARP3 protein levels, by Western-blot. Telomerase activity was determined by TRAP assay.

Results

In A549 cells, after PARP3 transient transfection, data obtained indicated that twenty-four hours after transfection, up to 100-fold increased gene expression levels were found in the transfected cells with pcDNA/GW-53/PARP3 in comparison to transfected cells with the empty vector. Moreover, 48 hours post-transfection, telomerase activity decreased around 33%, and around 27%, 96 hours post-transfection. Telomerase activity average ratio was 0.67 ± 0.05, and 0.73 ± 0.06, respectively, with significant differences. In Saos-2 cells, after shRNA-mediated PARP3 silencing, a 2.3-fold increase in telomerase activity was detected in relation to the control.

Conclusion

Our data indicated that, at least in some cancer cells, repression of PARP3 could be responsible for an increased telomerase activity, this fact contributing to telomere maintenance and, therefore, avoiding genome instability.     

The anxiolytic-like effect of an essential oil derived from Spiranthera odoratissima A. St. Hil. leaves and its major component, β-caryophyllene, in male mice

Spiranthera odoratissima A. St. Hil. (manacá) is used in folk medicine to treat renal and hepatic diseases, stomachache, headaches and rheumatism. A central nervous system (CNS) depressant effect of the hexane fraction from the ethanolic extract of this plant has been described. β-caryophyllene, the main component of this essential oil, is a sesquiterpene compound with anti-inflammatory properties that has been found in essential oils derived from several medicinal plants. This work is aimed to evaluate the pharmacological activity of the essential oil obtained from S. odoratissima leaves (EO) and its major component on the murine CNS; we aimed to evaluate a possible anxiolytic-like effect and the underlying mechanisms involved. In an open field test, EO (500 mg/kg) and β-caryophyllene (50, 100 and 200 mg/kg) increased the crossing frequency (P<0.05) and, EO (250 and 500 mg/kg) and β-caryophyllene (200 mg/kg) increased the time spent in the center (P<0.05) without altering total crossings of the open field. EO and β-caryophyllene did not alter the number of falls in the rota-rod test (P>0.05). In the pentobarbital-induced sleep test, EO (500 mg/kg) and β-caryophyllene (200 and 400 mg/kg) decreased the latency to sleep (P<0.05), and EO (125, 250 and 500 mg/kg) (P<0.001) and β-caryophyllene (200 and 400 mg/kg) (P<0.05 and P<0.001) increased the sleep time. In anxiety tests, EO (500 mg/kg) and β-caryophyllene (100 and 200 mg/kg) increased head-dipping behavior (P<0.05) in the hole-board test, entries (P<0.05) into and time spent (P<0.05) on the open arms of the elevated plus maze (EPM), and number of transitions (P<0.05) and time spent in the light compartment (P<0.05) of a light-dark box (LDB). We further investigated the mechanism of action underlying the anxiolytic-like effect of EO and β-caryophyllene by pre-treating animals with antagonists of benzodiazepine (flumazenil) and 5-HT(1A) (NAN-190) receptors prior to evaluation using EPM and LDB. The anxiolytic-like effects of EO were significantly reduced by pre-treatment with NAN-190 (P<0.05) but not flumazenil (P>0.05). The anxiolytic-like effects of β-caryophyllene were not blocked by either NAN-190 or flumazenil (P>0.05). In conclusion, these results suggest that the essential oil derived from S. odoratissima produces an anxiolytic-like effect without altering motor performance and that this effect is mediated by 5-HT(1A) but not via benzodiazepine receptors. In addition, the major component, β-caryophyllene, also has an anxiolytic-like effect that may contribute to the effects of EO, but this effect does not seem to be mediated via 5-HT(1A) or benzodiazepine receptors.     

Secuelas de la violencia colectiva: hablan las víctimas del estudio ISAVIC

Objective

Despite the significant influence of collective violence on the health status of its victims, there are still many gaps in our understanding of the nature of the functional limitations this violence produces and its impact on victims’ wellbeing and quality of life. The ISAVIC study was carried out in the autonomous region of the Basque Country from 2005-2008 to estimate the effects of collective violence on health. The assessment included victims’ perceptions of these sequelae and their impact on health.

Methods

A purposive sample of 36 primary victims was selected through contact networks and mediators. The victims’ perceptions were collected through semi-structured in-depth interviews, which were later analyzed according to the study's conceptual framework.

Results

The victims’ testimony suggests that they were profoundly traumatized by the collective violence experienced, which was often not yet completely overcome and significantly impaired their quality of life. The main functional, physical, emotional and social limitations described by the victims were identified.

Conclusions

The qualitative results of this study are coherent with those obtained through the parametric phase of the ISAVIC study and provide a more complete overview of the nature of the sequelae of collective violence and its impact on quality of life. These results should be verified in larger studies and the influence of the social context on the relationship between collective violence and health should be analyzed in greater depth.     

Conserved Threonine Residues within the A-Loop of the Receptor NIK Differentially Regulate the Kinase Function Required for Antiviral Signaling

NSP-interacting kinase (NIK1) is a receptor-like kinase identified as a virulence target of the begomovirus nuclear shuttle protein (NSP). We found that NIK1 undergoes a stepwise pattern of phosphorylation within its activation-loop domain (A-loop) with distinct roles for different threonine residues. Mutations at Thr-474 or Thr-468 impaired autophosphorylation and were defective for kinase activation. In contrast, a mutation at Thr-469 did not impact autophosphorylation and increased substrate phosphorylation, suggesting an inhibitory role for Thr-469 in kinase function. To dissect the functional significance of these results, we used NSP-expressing virus infection as a mechanism to interfere with wild type and mutant NIK1 action in plants. The NIK1 knockout mutant shows enhanced susceptibility to virus infections, a phenotype that could be complemented with ectopic expression of a 35S-NIK1 or 35S-T469A NIK1 transgenes. However, ectopic expression of an inactive kinase or the 35S-T474A NIK1 mutant did not reverse the enhanced susceptibility phenotype of knockout lines, demonstrating that Thr-474 autophosphorylation was needed to transduce a defense response to geminiviruses. Furthermore, mutations at Thr-474 and Thr-469 residues antagonistically affected NIK-mediated nuclear relocation of the downstream effector rpL10. These results establish that NIK1 functions as an authentic defense receptor as it requires activation to elicit a defense response. Our data also suggest a model whereby phosphorylation-dependent activation of a plant receptor-like kinase enables the A-loop to control differentially auto- and substrate phosphorylation.