Ex vivo and in vivo biological behavior of Leishmania (Viannia) shawi

Since the first description of Leishmania (Viannia) shawi, few studies were performed with this parasite. In the present work, the in vivo and ex vivo behavior of L. (Viannia) shawi infection was studied using murine model. Peritoneal macrophages from BALB/c and C57BL/6 mice were infected with promastigotes in the stationary phase of growth; after 24 h, the infection index and nitric oxide (NO) levels in the supernatant of the cultures were analyzed. BALB/c and C57BL/6 mice were infected into the hind footpad, and at each 2 weeks, mice were sacrificed, and the histological changes of the skin inoculation site, parasitism, and humoral immune responses were evaluated during 8 weeks. Ex vivo experiments showed that macrophages of BALB/c presented higher infection index and lesser NO levels than macrophages of C57BL/6. In vivo experiments showed that BALB/c presented higher lesion size than C57BL/6 mice; similarly, the histopathological changes and the parasitism in skin were more exacerbate in BALB/c mice. In draining lymph nodes, the main change was increase of germinative centers, and parasites were detected from 6 weeks pi onwards in both mice strain. IgG was detected in BALB/c mice from 4 weeks, while in C57BL/6, from 6 weeks pi onwards. Taken together, these results indicate that BALB/c showed a classical behavior of susceptibility when compared to C57BL/6 mice.

Individual vulnerability to escalated aggressive behavior by a low dose of alcohol: decreased serotonin receptor mRNA in the prefrontal cortex of male mice

Low to moderate doses of alcohol consumption induce heightened aggressive behavior in some, but not all individuals. Individual vulnerability for this nonadaptive behavior may be determined by an interaction of genetic and environmental factors with the sensitivity of alcohol`s effects on brain and behavior. We used a previously established protocol for alcohol oral self-administration and characterized alcohol-heightened aggressive (AHA) mice as compared with alcohol non-heightened (ANA) counterparts. A week later, we quantified mRNA steady state levels of several candidate genes in the serotonin [5-hydroxytryptamine (5-HT)] system in different brain areas. We report a regionally selective and significant reduction of all 5-HT receptor subtype transcripts, except for 5-HT(3), in the prefrontal cortex of AHA mice. Comparable gene expression profile was previously observed in aggressive mice induced by social isolation or by an anabolic androgenic steroid. Additional change in the 5-HT(1B) receptor transcripts was seen in the amygdala and hypothalamus of AHA mice. In both these areas, 5-HT(1B) mRNA was elevated when compared with ANA mice. In the hypothalamus, AHA mice also showed increased transcripts for 5-HT(2A) receptor. In the midbrain, 5-HT synthetic enzyme, 5-HT transporter and 5-HT receptors mRNA levels were similar between groups. Our results emphasize a role for postsynaptic over presynaptic 5-HT receptors in mice which showed escalated aggression after the consumption of a moderate dose of alcohol. This gene expression profile of 5-HT neurotransmission components in the brain of mice may suggest a vulnerability trait for alcohol-heightened aggression.

Performance of patients with refractory obsessive-compulsive disorder in the Frontal Systems Behavior Scale

Objective: To compare the performance of patients with obsessive-compulsive disorder (OCD) refractory to conventional treatments to healthy controls according to the Frontal Systems Behaviour Scale (FrSBe), comparing the scale scores within each group (Self or Family) and correlating FrSBe with Y-BOCS, DY-BOCS, tic disorder and age of first symptoms. Method: Twenty OCD patients and 20 healthy controls were assessed using the FrSBe, a scale designed to evaluate frontal syndromes. Results: The patients had higher scores when compared with the control group (p value .001) in terms of total score on the scale for both profile forms (Self and Family). In addition, there was a significant difference between the scores reported by the patients and their respective relatives. However, no correlation was observed between the scale and the other variables. Conclusions: The scale was able to clearly differentiate patients with OCD from healthy controls. This finding suggests that the FrSBe can be used not only in neurologic patients but also in psychiatric cases such as refractory OCD.

Suicide behavior and neuropsychological assessment of type I bipolar patients

Background: Neuropsychological deficits are often described in patients with bipolar disorder (BID). Some symptoms and/or associated characteristics of BD can be more closely associated to those cognitive impairments. We aimed to explore cognitive neuropsychological characteristics of type I bipolar patients (BPI) in terms Of lifetime Suicide attempt history. Method: We studied 39 BPI Outpatients compared with 53 healthy controls (HC) matched by age, educational and intellectual level. All Subjects were submitted to a neuropsychological assessment of executive functions, decision-making and declarative episodic memory. Results: When comparing BD1 patients, regardless of suicide attempt history or HC, we observed that bipolar patients performed worse than controls oil measures of memory, attention, executive functions and decision-making, Patients with a history of suicide attempt performed worse than non-attempters on measures of decision-making and there were a significant negative correlation between the number of suicide attempts and decision-making results (block 3 and net score). We also found significant Positive correlation between the number Of Suicide attempts and amount Of errors in Stroop Color Word Test (part 3). Limitations: The sample Studied call be considered small and a potentially confounding variable - medication status - were not controlled. Conclusion: Our results show the presence of neuropsychological deficits in memory, executive functions, attention and decision-making in BPI patients. Suicide attempts BPI scored worse than non-suicide attempt Bill oil measures of decision-making. More suicide attempts were associated with a worse decision-making process. Future research should explore the relationship between the association between this specific cognitive deficits in BPIs, serotonergic function and suicide behavior in bipolar patients as well other diagnostic groups. (C) 2009 Elsevier B.V. All rights reserved.

Association between personality disorder and violent behavior pattern

Personality disorders are associated with criminality and antisocial and borderline personalities as strong predictors of violence. Nevertheless antisocial patients show more instrumental violence, while borderline patients more emotional violence. We surveilled medical records of a personality disorder facility, searching data of aggression and crimes against property among 11 patients with antisocial personality disorder and 19 borderline personality disorder. We found that there are differences regarding engagement in violence and lawbreaking according to the personality disorder: antisocial patients statistically engage more in crimes against property than the borderline patients, and more in this kind of crime than in aggression, whilst borderline patients show a tendency to engage more in episodes of aggression and physical violence than antisocial patients, and less in crimes against property. We conclude that the distinct personality leads to a distinct pattern of crimes and violence: antisocial patients are c old and get more involved in crimes requiring more detailed planning, whilst borderline patients are impulsive and engage in explosive episodes of physical violence. Further studies on the association among personality disorder, behavior pattern and violence type may be useful for both treatment and criminal profiling. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Schistosoma mansoni encodes SMT3B and SMT3C molecules responsible for post-translational modification of cellular proteins

The sumoylation pathway is a post-translational modification of nuclear proteins widespread among several organisms. SMT3C is the main protein involved in this process and it is covalently conjugated to a diverse assortment of nuclear protein targets. To date, 3 SUMO paralogues (SMT3C, A/B) have been characterized in mammals and plants. In this work we characterized two SUMO related genes, named SMT3B and SMT3C throughout Schistosoma mansoni life cycle. The SmSMTB/C encodes for proteins sharing significant amino acid homology with SMT3. Phylogenetical analyses revealed that both SmSMT3B/C are distinct proteins. Additionally, SmSMT3B and C are expressed in cercariae, adult worms, eggs and schistosomula however SinSMT3C gene showed an expression level 7 to 9 fold higher than SmSMT3B in eggs, schistosomula and adult worms. The comparison between the SmSMT3C genomic and cDNA sequences established that the encoding sequence is interrupted by 3 introns of 70, 37 and 36 bp. Western Blot has shown SMT3 conjugates are present in nuclear and total protein fractions of adults and cercariae. Therefore our results suggest a functional sumoylation pathway, and the presence of two paralogues also suggests the specificity of substrates for SMT3 in S. mansoni. (c) 2008 Elsevier Ireland Ltd. All rights reserved.

Influence of treadmill training on motor performance and organization of exploratory behavior in Meriones unguiculatus with unilateral ischemic stroke: Histological correlates in hippocampal CA1 region and the neostriatum

This study examined the effects of motor stimulation via treadmill on the behavior of male gerbils after external carotid ischemic brain lesion. The animals were assigned to five groups; ischemic with no stimulation (SIG), ischemic with stimulation (SIG 12/24/48/72 It after surgery), non-ischemic with no stimulation (CC), non-ischemic with stimulation (CE) and sham, surgery without occlusion with no stimulation (SH). All the animals were tested in the open-field (OF) and rotarod (RR), 4 days after surgery in order to evaluate exploratory behaviors and motor performance. Data were submitted to one-way variance (ANOVA) and Dunnett`s post hoc comparisons. SIG and SIG 12 groups showed a significant decrease in motor response (crossing) when compared to the control group (CC) (F = 20.65, P < 0.05) in the OF. SIG 12 group showed an increase in grooming behavior (F = 23.136, P < 0.05) and all ischemia groups (SIG, SIG 12/24/48/72) spent less time on the RR (F = 10.40, P < 0.05), when compared to the control group (CC). Histological analyses show extensive lesions in the hippocampus and neostriatum for all groups with ischemia (SIG, SIG 12/24/48/72), which are structures involved in the organization of motor behavior. Interestingly, the most pronounced damage was found in animals submitted to motor stimulation 12 h after ischemia which can be correlated to the increased number of grooming behavior showed by them in the OF. These findings suggest that motor stimulation through treadmill training improve motor behavior after ischemia, except when it starts 12h after surgery. (c) 2007 Elsevier Ireland Ltd. All rights reserved.

Dorsal raphe nucleus regulation of a panic-like defensive behavior evoked by chemical stimulation of the rat dorsal periaqueductal gray matter

Electrical or chemical stimulation of the dorsal periaqueductal gray matter (DPAG) evokes escape, a defensive behavior that has been related to panic attacks. Injection of 5-HT(1A) or 5-HT(2A) receptor agonists into this midbrain area inhibits this response. It has been proposed that the impairment of 5-HT mechanisms controlling escape at the level of the DPAG may underlie the susceptibility to panic attacks that characterizes the panic disorder. In this study we evaluated the effects of the pharmacological manipulation of the dorsal raphe nucleus (DRN), which are the main source of 5-HT input to the DPAG, on the escape response evoked in rats by the intra-DPAG injection of the nitric oxide donor SIN-1. The results showed that DRN administration of the 5-HT(1A) receptor agonist 8-OH-DPAT which inhibits the activity of 5-HT neurons favored the expression of escape induced by SIN-1. Intra-DRN injection of the excitatory amino acid kainic acid or the 5-HT(1A) receptor antagonist WAY-100635 did not change escape expression. However, both compounds fully blocked the escape reaction generated by intra-DPAG injection of the excitatory amino acid D,L-homocysteic acid (DLH). Overall, the results indicate that 5-HT neurons in the DRN exert a bidirectional control upon escape behavior generated by the DPAG. Taking into account the effect of WAY-100635 on DLH-induced escape, they also strengthen the view that DRN 5-HT(1A) autoreceptors are under tonic inhibitory influence by 5-HT. (C) 2010 Elsevier B.V. All rights reserved.