Development of the nasal chemosensory organs in two terrestrial anurans: the directly developing frog, Eleutherodactylus coqui (Anura: Leptodactylidae), and the metamorphosing toad, Bufo americanus (Anura: Bufonidae)

Nearly all vertebrates possess an olfactory organ but the vomeronasal organ is a synapomorphy for tetrapods. Nevertheless, it has been lost in several groups of tetrapods, including aquatic and marine animals. The present study examines the development of the olfactory and vomeronasal organs in two terrestrial anurans that exhibit different developmental modes. This study compares the development of the olfactory and vomeronasal organs in metamorphic anurans that exhibit an aquatic larva (Bufo americanus) and directly developing anurans that have eliminated the tadpole (Eleutherodactylus coqui). The olfactory epithelium in larval B. americanus is divided into dorsal and ventral branches in the rostral and mid-nasal regions. The larval olfactory pattern in E. coqui has been eliminated. Ontogeny of the olfactory system in E. coqui embryos starts to vary substantially from the larval pattern around the time of operculum development, the temporal period when the larval stage is hypothesized to have been eliminated. The nasal anatomy of the two frogs does not appear morphologically similar until the late stages of embryogenesis in E. coqui and the terminal portion of metamorphosis in B. americanus. Both species and their respective developing offspring, aquatic tadpoles and terrestrial egg/embryos, possess a vomeronasal organ. The vomeronasal organ develops at mid-embryogenesis in E. coqui and during the middle of the larval period in B. americanus, which is relatively late for neobatrachians. Development of the vomeronasal organ in both frogs is linked to the developmental pattern of the olfactory system. This study supports the hypothesis that the most recent common ancestor of tetrapods possessed a vomeronasal organ and was aquatic, and that the vomeronasal organ was retained in the Amphibia, but lost in some other groups of tetrapods, including aquatic and marine animals.     

Salmonella enterica serotype Typhimurium MisL is an intestinal colonization factor that binds fibronectin

MisL is an autotransporter protein encoded by Salmonella pathogenicity island 3 (SPI3). To investigate the role of MisL in Salmonella enterica serotype Typhimurium (S. Typhimurium) pathogenesis, we characterized its function during infection of mice and identified a host receptor for this adhesin. In a mouse model of S. Typhimurium intestinal persistence, a misL mutant was shed with the faeces in significantly lower numbers than the wild type and was impaired in its ability to colonize the cecum. Previous studies have implicated binding of extracellular matrix proteins as a possible mechanism for S. Typhimurium intestinal persistence. A gluthathione-S-transferase (GST) fusion protein to the MisL passenger domain (GST-MisL(29-281)) was constructed to investigate binding to extracellular matrix proteins. In a solid-phase binding assay the purified GST-MisL(29-281) fusion protein bound to fibronectin and collagen IV, but not to collagen I. MisL expression was not detected by Western blot in S. Typhimurium grown under standard laboratory conditions. However, when expression of the cloned misL gene was driven by the Escherichia coli arabinose promoter, MisL could be detected in the S. Typhimurium outer membrane by Western blot and on the bacterial cell surface by flow cytometry. Expression of MisL enabled S. Typhimurium to bind fibronectin to its cell surface, resulting in attachment to fibronectin-coated glass slides and in increased invasiveness for human epithelial cells derived from colonic carcinoma (T84 cells). These data identify MisL as an extracellular matrix adhesin involved in intestinal colonization.     

Thermal behavior of HeLa and KB cells in suspension and attached to glass

HeLa S-3 and KB cells were grown in a LKB Batch Microcalorimeter under a variety of nutrient medium conditions amd mixing intervals. These conditions produced rather large apparent endothermic and exothermic responses on mixing that could be correlated with the presence of suspended cells (unattached) as well as cells attached to the glass calorimeter vessel. Cells capable of being resuspended upon mixing of the calorimeter vessel produces first an endothermic followed by an exothermic signal while attached cells produced only an apparent endothermic response. The exothermic response is believed to be associated with increased metabolic heat on suspending the cells followed by partial suppression of the steady state metabolic heat on cell settling. Rates of cell settling correlated well with the rate of decay of the exothermic signal. The rapid appearance of endothermicity on mixing suggests it is associated with rapid events such as binding of nutrients to cell surfaces. The response in the endothermic direction on mixing is discussed in terms of the disruption of mechanisms which tend to exclude nutrients from the surface of the cell.     

Insulin,Central Dopamine D2 Receptors,and Monetary Reward Discounting in Obesity

Animal research finds that insulin regulates dopamine signaling and reward behavior, but similar research in humans is lacking. We investigated whether individual differences in body mass index, percent body fat, pancreatic β-cell function, and dopamine D2 receptor binding were related to reward discounting in obese and non-obese adult men and women. Obese (n = 27; body mass index>30) and non-obese (n = 20; body mass index<30) adults were assessed for percent body fat with dual-energy X-ray absorptiometry and for β-cell function using disposition index. Choice of larger, but delayed or less certain, monetary rewards relative to immediate, certain smaller monetary rewards was measured using delayed and probabilistic reward discounting tasks. Positron emission tomography using a non-displaceable D2-specific radioligand, [¹¹C](N-methyl)benperidol quantified striatal D2 receptor binding. Groups differed in body mass index, percent body fat, and disposition index, but not in striatal D2 receptor specific binding or reward discounting. Higher percent body fat in non-obese women related to preference for a smaller, certain reward over a larger, less likely one (greater probabilistic discounting). Lower β-cell function in the total sample and lower insulin sensitivity in obese related to stronger preference for an immediate and smaller monetary reward over delayed receipt of a larger one (greater delay discounting). In obese adults, higher striatal D2 receptor binding related to greater delay discounting. Interestingly, striatal D2 receptor binding was not significantly related to body mass index, percent body fat, or β-cell function in either group. Our findings indicate that individual differences in percent body fat, β-cell function, and striatal D2 receptor binding may each contribute to altered reward discounting behavior in non-obese and obese individuals. These results raise interesting questions about whether and how striatal D2 receptor binding and metabolic factors, including β-cell function, interact to affect reward discounting in humans.     

A Transdiagnostic Community-Based Mental Health Treatment for Comorbid Disorders: Development and Outcomes of a Randomized Controlled Trial among Burmese Refugees in Thailand

Background

Existing studies of mental health interventions in low-resource settings have employed highly structured interventions delivered by non-professionals that typically do not vary by client. Given high comorbidity among mental health problems and implementation challenges with scaling up multiple structured evidence-based treatments (EBTs), a transdiagnostic treatment could provide an additional option for approaching community-based treatment of mental health problems. Our objective was to test such an approach specifically designed for flexible treatments of varying and comorbid disorders among trauma survivors in a low-resource setting.

Methods and Findings

We conducted a single-blinded, wait-list randomized controlled trial of a newly developed transdiagnostic psychotherapy, Common Elements Treatment Approach (CETA), for low-resource settings, compared with wait-list control (WLC). CETA was delivered by lay workers to Burmese survivors of imprisonment, torture, and related traumas, with flexibility based on client presentation. Eligible participants reported trauma exposure and met severity criteria for depression and/or posttraumatic stress (PTS). Participants were randomly assigned to CETA (n = 182) or WLC (n = 165). Outcomes were assessed by interviewers blinded to participant allocation using locally adapted standard measures of depression and PTS (primary outcomes) and functional impairment, anxiety symptoms, aggression, and alcohol use (secondary outcomes). Primary analysis was intent-to-treat (n = 347), including 73 participants lost to follow-up. CETA participants experienced significantly greater reductions of baseline symptoms across all outcomes with the exception of alcohol use (alcohol use analysis was confined to problem drinkers). The difference in mean change from pre-intervention to post-intervention between intervention and control groups was −0.49 (95% CI: −0.59, −0.40) for depression, −0.43 (95% CI: −0.51, −0.35) for PTS, −0.42 (95% CI: −0.58, −0.27) for functional impairment, −0.48 (95% CI: −0.61, −0.34) for anxiety, −0.24 (95% CI: −0.34, −0.15) for aggression, and −0.03 (95% CI: −0.44, 0.50) for alcohol use. This corresponds to a 77% reduction in mean baseline depression score among CETA participants compared to a 40% reduction among controls, with respective values for the other outcomes of 76% and 41% for anxiety, 75% and 37% for PTS, 67% and 22% for functional impairment, and 71% and 32% for aggression. Effect sizes (Cohen''s d) were large for depression (d = 1.16) and PTS (d = 1.19); moderate for impaired function (d = 0.63), anxiety (d = 0.79), and aggression (d = 0.58); and none for alcohol use. There were no adverse events. Limitations of the study include the lack of long-term follow-up, non-blinding of service providers and participants, and no placebo or active comparison intervention.

Conclusions

CETA provided by lay counselors was highly effective across disorders among trauma survivors compared to WLCs. These results support the further development and testing of transdiagnostic approaches as possible treatment options alongside existing EBTs.

Trial registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01459068","term_id":"NCT01459068"}}NCT01459068 Please see later in the article for the Editors'' Summary