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The zebrafish has been considered an ideal model for studies of complex behaviors since its behavioral repertoire is well described. Therefore, this study evaluated the perceived pain through behavioral changes in zebrafish larvae. Here we investigated the Acetic Acid (AA) effects on zebrafish larvae exposed in a short-time period (60 s) and the preventive effect from routinely used compounds, Dimethyl Sulfoxide (DMSO), Ethanol (EtOH), Ibuprofen (IBP), and Paracetamol (PAR). In addition, the effect of P2×7 antagonist, A740003, and pannexin channel 1 (PANX-1) inhibitor Probenecid (PROB) on AA-induced behavioral changes were evaluated. AA impaired the distance covered, acceleration, movement, and latency to the first entry in the center from 5 dpf exposed larvae. At 0.050% AA, PAR prevented alterations from the distance covered, acceleration, and movement. Surprisingly, 0.3% DMSO prevented behavioral changes induced by AA. However, the effects from 0.2% DMSO were not prominent. We used 0.2% DMSO as a PROB diluent. PROB prevented the changes in distance and movement observed at both AA concentrations (0.0025% and 0.05%) tested. Since EtOH had no analgesic properties, we used it as an A740003 vehicle to observe the analgesic effects of this compound. As noted, A740003 did not prevent the behavioral changes in the AA-induced pain model. In contrast, 0.2% DMSO and PROB prevented AA-induced behavioral changes. These data enforce that zebrafish could be used in translational studies since this species has behavioral responses related to pain in the early stages of development and responses to analgesics similar to observed in mammals., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Oxytetracycline (OTC) is one of the broad-spectrum antibiotics widely used for the treatment of fish-farm infection. Considering that behavior is directly related to reproduction, individual fitness, and survival, it is important to evaluate the impact of antibiotics on the behavioral repertoire in fish. Zebrafish (Danio rerio) presents a well-described behavioral repertoire to reliably demonstrate complex responses to chemical compound exposure. This work aims to identify the role of OTC in comprehensive behavioral parameters and whole-body cortisol levels in adult zebrafish. Here we report that OTC exposure (10, 20, and 100 mg/L) induces an anxiogenic-like phenotype in the novel tank test. OTC exposure also changes the behavior of social interaction with a shoal of unknown zebrafish - characterized as a stimulus group. Zebrafish exposed to OTC (10 mg/L) remains a longer period in the stimulus zone when compared to the control group. Clonazepam (0.006 mg/L) was able to reverse anxiogenic-like behavior and the changes in social behavior induced by OTC. We also demonstrated that cortisol levels were significantly decreased after exposure to OTC (10, 20, and 100 mg/L), which were not reversed by clonazepam. These findings highlight the growing utility of zebrafish as a model to understand the impact of antibiotics on behavior and their underlying mechanisms., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Visual systems transduce, process and transmit light-dependent environmental cues. Computation of visual features depends on photoreceptor neuron types (PR) present, organization of the eye and wiring of the underlying neural circuit. Here, we describe the circuit architecture of the visual system of Drosophila larvae by mapping the synaptic wiring diagram and neurotransmitters. By contacting different targets, the two larval PR-subtypes create two converging pathways potentially underlying the computation of ambient light intensity and temporal light changes already within this first visual processing center. Locally processed visual information then signals via dedicated projection interneurons to higher brain areas including the lateral horn and mushroom body. The stratified structure of the larval optic neuropil (LON) suggests common organizational principles with the adult fly and vertebrate visual systems. The complete synaptic wiring diagram of the LON paves the way to understanding how circuits with reduced numerical complexity control wide ranges of behaviors., Competing Interests: IL, PF, NG, GN, RF, CS, JT, MZ, AC, SS No competing interests declared, (© 2017, Larderet et al.)

Background: Although it is known that first degree relatives of celiac patients have an increased risk for celiac disease few studies are available on its incidence. We investigated the incidence of serologic conversion and of new cases of celiac disease among first degree relatives with negative results at a first screening., Methods: From a total of 634 first degree relatives of 186 biopsy-proven celiac disease patients diagnosed between October 2000 and October 2010, 450 subjects agreed to participate in the study (Group I), and underwent serologic screening. Between January 2010 and October 2012, out of the initial group of 450, 205 previously sero-negative subjects consented to participate in a second stage of the study and undergo new serologic testing (Group II). All serologically positive individuals of both groups (I and II) were genotyped for celiac disease-predisposing alleles (HLA-DQ2/DQ8)., Results: 19 subjects (4.2%) out of the 450 subjects of Group I disclosed positive serologic results, presence of DQ2 and/or DQ8 alleles and celiac disease-compatible mucosal abnormalities. The 205 previously negative first degree relatives from Group II that underwent new serologic testing disclosed eight sero-converted subjects. Mucosal abnormalities in five of these patients confirmed the diagnosis of celiac disease. During the 10-year period of the study the incidence of sero-conversion was 8/205 and the incidence of biopsy-proven celiac disease cases was 5/205., Conclusions: Our data are coincident with other works on this subject and confirm once again that relatives of celiac patients, especially first degree relatives are at high risk of developing celiac disease. In view of the relatively low incidence further studies are needed to try to establish a useful and cost-effective algorithm for follow-up of relatives of celiac patients.

Aim: To evaluate the prevalence of celiac disease in a group of Brazilian individuals over 60 years of age and compare it with the previously known prevalence in a pediatric group living in the same geographical area., Methods: The research protocol was approved by the Ethics Committee of the University of Brasilia School of Medicine, Brasilia, Brazil. Blood samples from 946 individuals (295 male and 651 female) aged 60 years or older were collected between May 2010 and July 2011. The study subjects' mean and median ages were 68.1 and 67 years, respectively, ranging from 60 to 92 years. That age distribution closely corresponded to the age distribution of the Brazilian population according to the Brazilian 2010 census. The participants were consecutive and unselected outpatients undergoing blood tests at the University of Brasilia Hospital's Clinical Pathology Laboratory. All sera were tested for immunoglobulin A anti-transglutaminase antibodies (IgA-tTG) by enzyme- linked immunosorbent assay, and those that were positive were further tested for immunoglobulin A anti-endomysium antibodies (IgA-EMA). Human leukocyte antigen (HLA) genotyping was performed for all individuals who exhibited positive serologic results for IgA-tTG and/or IgA-EMA., Results: Out of the 946 studied patients, only one previously diagnosed case of biopsy-proven celiac disease was detected. For the remaining subjects, nine serum samples tested positive for IgA-tTG antibodies; however, none of them tested positive for IgA-EMA antibodies. The HLA genotyping of those nine subjects revealed that one was carrying DQA1*0501 and two were carrying DQB1*0201 alleles. These data showed that, among those 946 elderly individuals, the prevalence of celiac disease (CD) was 0.1% (95%CI: 0.00-0.59). The prevalence of CD for the elderly group was compared with that observed for the group of 2034 children younger than 15 years (age range, 1-14 years; mean age, 8 years) who took part in our previous CD prevalence screening study. All the children came from the same geographical region and shared a similar ethnic and low-income background. As in the elderly group in the current study, the younger group was made up of consecutive outpatients who underwent blood evaluation at the University of Brasilia Hospital's Clinical Laboratory. The prevalence of biopsy-proven CD among those children was 0.54% (95%CI: 0.27-0.57). The comparative analysis between the two groups resulted in the following values: odds ratio = 0.19 (95%CI: 0.01-1.45) Fisher test P = 0.06., Conclusion: The prevalence of CD among the children of our previous study was 5.4 times higher than that found in the present elderly group.