Role of environmental enrichment on social interaction, anxiety, locomotion, and memory in Wistar rats under chronic methylphenidate intake.

Introduction: Chronic use of various compounds can have long-lasting effects on animal behavior, and some of these effects can be influenced by the environment. Many environmental enrichment protocols have the potential to induce behavioral changes.

Aim: The aim of the present study was to investigate how environmental enrichment can mitigate the effects of chronic methylphenidate consumption on the behavior of Wistar rats.

Providing Environmental Enrichment without Altering Behavior in Male and Female Wistar Rats ().

In research using animal models, subjects are commonly maintained under standard housing conditions, mainly because of the idea that enhancing welfare conditions could alter experimental data. Another common practice in many laboratories relates to the preponderant use of males. Several reasons justifying this practice include the rapid hormonal and endocrine change in females, which may require a higher number of female animals to achieve more homogenous groups, thereby creating a dilemma with the reduction principle in animal research.

Post-recurrence survival in patients with cervical cancer.

Background: Up to 26% of patients with early-stage cervical cancer experience relapse after primary surgery. However, little is known about which factors influence prognosis following disease recurrence. Therefore, our aims were to determine post-recurrence disease-specific survival (PR-DSS) and to identify respective prognostic factors for PR-DSS.

Cathodal transcranial direct current stimulation on the prefrontal cortex applied after reactivation attenuates fear memories and prevent reinstatement after extinction.

Background: In the last decade, pharmacological strategies targeting reconsolidation after memory retrieval have shown promising efforts to attenuate persistent memories and overcome fear recovery. However, most reconsolidation inhibiting agents have not been approved for human testing. While non-invasive neuromodulation can be considered an alternative approach to pharmacological treatments, there is a lack of evidence about the efficacy of these technologies when modifying memory traces via reactivation/reconsolidation mechanism.

Fear Incubation Using an Extended Fear-Conditioning Protocol for Rats.

Emotional memory has been primarily studied with fear-conditioning paradigms. Fear conditioning is a form of learning through which individuals learn the relationships between aversive events and otherwise neutral stimuli. The most-widely utilized procedures for studying emotional memories entail fear conditioning in rats.

Distinct patterns of brain Fos expression in Carioca High- and Low-conditioned Freezing Rats.

Background: The bidirectional selection of high and low anxiety-like behavior is a valuable tool for understanding the neurocircuits that are responsible for anxiety disorders. Our group developed two breeding lines of rats, known as Carioca High- and Low-conditioned Freezing (CHF and CLF), based on defensive freezing in the contextual fear conditioning paradigm. A random selected line was employed as a control (CTL) comparison group for both CHF and CLF lines of animals.

Synaptic plasticity in Alzheimer's disease and healthy aging.

The strength and efficiency of synaptic connections are affected by the environment or the experience of the individual. This property, called synaptic plasticity, is directly related to memory and learning processes and has been modeled at the cellular level. These types of cellular memory and learning models include specific stimulation protocols that generate a long-term strengthening of the synapses, called long-term potentiation, or a weakening of the said long-term synapses, called long-term depression.

A systematic review of brain functional connectivity patterns involved in episodic and semantic memory.

The study of functional connectivity and declarative memory has lately been focused on finding biomarkers of neuropsychological diseases. However, little is known about its patterns in healthy brains. Thus, in this systematic review we analyze and integrate the findings of 81 publications regarding functional connectivity (measured by fMRI during both task and resting-state) and semantic and episodic memory in healthy adults.

Behavioral Effects of Systemic, Infralimbic and Prelimbic Injections of a Serotonin 5-HT Antagonist in Carioca High- and Low-Conditioned Freezing Rats.

The role of serotonin (5-hydroxytryptamine [5-HT]) and 5-HT receptors in anxiety has been extensively studied, mostly without considering individual differences in trait anxiety. Our laboratory developed two lines of animals that are bred for high and low freezing responses to contextual cues that are previously associated with footshock (Carioca High-conditioned Freezing [CHF] and Carioca Low-conditioned Freezing [CLF]). The present study investigated whether ketanserin, a preferential 5-HT receptor blocker, exerts distinct anxiety-like profiles in these two lines of animals.

Running wheel training does not change neurogenesis levels or alter working memory tasks in adult rats.

Background: Exercise can change cellular structure and connectivity (neurogenesis or synaptogenesis), causing alterations in both behavior and working memory. The aim of this study was to evaluate the effect of exercise on working memory and hippocampal neurogenesis in adult male Wistar rats using a T-maze test.

Methods: An experimental design with two groups was developed: the experimental group ( = 12) was subject to a forced exercise program for five days, whereas the control group ( = 9) stayed in the home cage.

Effect of Overcrowding on Hair Corticosterone Concentrations in Juvenile Male Wistar Rats.

In many species, chronic stress due to overcrowding during the juvenile period triggers several metabolic and behavioral pathologies in adulthood. The aim of this study was to determine whether a chronic stress condition (overcrowding) induces changes in plasma and hair corticosterone concentrations, overall growth, and organ weights in young Wistar rats. The experimental subjects were divided into 2 groups (control and overcrowded); the overcrowded subjects were exposed to overcrowding during days 38 through 65 after birth.

Medial orbitofrontal cortex lesion prevents facilitatory effects of d-cycloserine during fear extinction.

Animal models of fear extinction have an important clinical relevance to pharmacological and exposure-based therapies for anxiety disorders. Lesions of prefrontal structures impair fear extinction. On the other hand, d-cycloserine is able to enhance this process.

Contribution of the parafascicular nucleus in the spontaneous object recognition task.

The parafascicular (PF) nucleus, a posterior component of the intralaminar nuclei of the thalamus, is considered to be an essential structure in the feedback systems of basal ganglia-thalamo-cortical circuits critically involved in cognitive processes. The specific role played by multimodal information encoded in PF neurons in learning and memory processes is still unclear. We conducted two experiments to investigate the role of the PF in the spontaneous object recognition (SOR) task.

The effects of pentylenetetrazol, chlordiazepoxide and caffeine in rats tested in the elevated plus-maze depend on the experimental illumination.

The so-called anxiolytic and anxiogenic drugs are considered to cause, respectively, increases and decreases in plus-maze open arm exploration, without modifying locomotor activity occurring in the closed arms in an elevated plus-maze when the animals are tested in an illuminated environment. Simply testing animals in the dark also increases open arm exploration, which may be interpreted as an anxiolytic effect. We investigated the effects of two GABAergic drugs, pentylenetetrazol (10 and 20 mg/kg) and chlordiazepoxide (1.

Effects of chronic intracerebroventricular 3,4-methylenedioxy-N-methamphetamine (MDMA) or fluoxetine on the active avoidance test in rats with or without exposure to mild chronic stress.

In despite the similarity of mechanisms of action between both selective serotonin reuptake inhibitors (SSRI) and MDMA (main compound of "Ecstasy") there are relatively few reports on the effects of the later on animal models of depression. There are many animal models designed to create or to assess depression. Mild chronic stress (MCS) is a procedure designed to create depression.

Racial and ethnic differences in unmet need for vision care among children with special health care needs.

Objective: To examine racial and ethnic differences in unmet need for vision care among children with special health care needs.

Methods: Cross-sectional data from the National Survey of Children with Special Health Care Needs were analyzed. The analytic sample was 14,070 children with special health care needs who needed eyeglasses or vision care in the previous year.

Effect of different illumination levels on rat behavior in the elevated plus-maze.

The present study addressed the role of environmental light intensity on the exploratory behavior of rats in the elevated plus-maze, with the specific goal of determining the light intensity threshold for triggering the aversion to the open arms. Male Wistar-derived rats were tested in the elevated plus-maze under different illumination levels: 0, 1, 3, 10, 30, 100 and 300 lx. Exploratory behavior occurring in the open arms (e.

Description of a seven-year prospective study of human papillomavirus infection and cervical neoplasia among 10000 women in Guanacaste, Costa Rica,

Objective: The Guanacaste study ("Guanacaste Project," or GP), was designed to investigate the role of human papillomavirus (HPV) infection and its cofactors in the development of cervical neoplasia and to evaluate new cervical cancer screening technologies. The follow-up phase of the GP was designed to study why a small proportion of women infected with HPV develop cervical intraepithelial neoplasia grade 2 (CIN 2), CIN 3, or cancer (these three together are globally referred to as > or = CIN 2, that is, CIN 2 or worse). The purpose of this article is to describe this prospective study in detail and to present the preliminary findings regarding the incidence of cervical neoplasia.

Correlates of IL-10 and IL-12 concentrations in cervical secretions.

Interindividual variations in host immune responses to HPV infection are thought to be important determinants of viral persistence and progression to cervical intraepithelial neoplasia and cancer. However, few studies have measured local immune markers at the site of infection (e.g.

The role of vision and proprioception in the aversion of rats to the open arms of an elevated plus-maze.

The elevated plus-maze test is usually run with a short edge surrounding the open arms in order to prevent the rats from falling. The present experiment investigated the role of transparent edges differing in heights: 1 (used as control), 5, 10, 20 and 40 cm, the latter the same height as the closed arm walls. Additionally, this 40-cm high transparent edge was also studied covered by white translucent or black opaque paper.

The distribution of fos immunoreactivity in rat brain following freezing and escape responses elicited by electrical stimulation of the inferior colliculus.

Several sources of evidence indicate that the inferior colliculus also integrates acoustic information of an aversive nature besides its well-known role as a relay station for auditory pathways. Gradual increases of the electrical stimulation of this structure cause in a hierarchical manner alertness, freezing and escape behaviors. Independent groups of animals implanted with bipolar electrodes into the inferior colliculus received electrical stimulation at one of these aversive thresholds.