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Emotional blunting and abnormal processing of rewards and punishments represent early features of frontotemporal lobar degeneration (FTLD). Better understanding of the physiological underpinnings of these emotional changes can be facilitated by the use of classical psychology approaches. Fear conditioning (FC) is an extensively used paradigm for studying emotional processing that has rarely been applied to the study of dementia. We studied FC in controls (n = 25), Alzheimer's disease (n = 25) and FTLD (n = 25). A neutral stimulus (coloured square on a computer screen) was repeatedly paired with a 1 s burst of 100 db white noise. Change in skin conductance response to the neutral stimulus was used to measure conditioning. Physiological-anatomical correlations were examined using voxel-based morphometry (VBM). Both patient groups showed impaired acquisition of conditioned responses. However, the basis for this deficit appeared to differ between groups. In Alzheimer's disease, impaired FC occurred despite normal electrodermal responses to the aversive stimulus. In contrast, FTLD patients showed reduced skin conductance responses to the aversive stimulus, which contributed significantly to their FC deficit. VBM identified correlations with physiological reactivity in the amygdala, anterior cingulate cortex, orbitofrontal cortex and insula. These data indicate that Alzheimer's disease and FTLD both show abnormalities in emotional learning, but they suggest that in FTLD this is associated with a deficit in basic electrodermal response to aversive stimuli, consistent with the emotional blunting described with this disorder. Deficits in responses to aversive stimuli could contribute to both the behavioural and cognitive features of FTLD and Alzheimer's disease. Further study of FC in humans and animal models of dementia could provide a valuable window into these symptoms. [ABSTRACT FROM AUTHOR]

Purpose: Dome-shaped macula (DSM) is known to occur in highly myopic adults and, recently, preterm infants. This study uses investigational handheld swept-source optical coherence tomography (SS-OCT) to further characterize infantile DSM., Methods: In this prospective, observational study, preterm infants undergoing retinopathy of prematurity screening and full-term infants within 72 hours of birth were imaged. Two trained graders assessed macular features, including DSM, subretinal fluid, and macular edema. A semi-automated program measured foveal immaturity, dome height, and diameter., Results: Two hundred seventeen imaging sessions from 50 full-term and 30 preterm infants were included (46% female, preterm birth weight 1038 ± 335 g, and gestational age 28.7 ± 3.1 weeks). DSM occurred in 40% preterm versus 14% full-term infants (P = 0.01). Mean postmenstrual age at first DSM diagnosis was 38.4 ± 0.0 weeks among preterm and 40.4 ± 1.1 weeks among full-term infants (P < 0.001). Dome height and diameter measured 55.67 ± 44.22 µm and 3583.15 ± 1090.35 µm for preterm versus 88.37 ± 44.73 µm and 3581.97 ± 355.07 µm for full-term infants (P = 0.24 and P = 0.96, respectively). All 27 images (11 preterm and 7 full-term infants) with 3-dimensional analysis had round dome configuration. No other associations were seen, including macular fluid (P = 0.17)., Conclusions: Infants frequently exhibit DSM without an association with macular fluid. Preterm infants were more likely than full-term infants to have DSM. Unlike DSM in children and adults, infantile DSM configuration is mostly round rather than ridge-shaped.

Tuberculosis (TB) is a leading cause of death among infectious diseases worldwide due to latent TB infection, which is the critical step for the successful pathogenic cycle. In this stage , Mycobacterium tuberculosis resides inside the host in a dormant and antibiotic-tolerant state. Latent TB infection can also lead to multisystemic diseases because M. tuberculosis invades virtually all organs, including ocular tissues. Ocular tuberculosis (OTB) occurs when the dormant bacilli within the ocular tissues reactivate, originally seeded by hematogenous spread from pulmonary TB. Histological evidence suggests that retinal pigment epithelium (RPE) cells play a central role in immune privilege and in protection from antibiotic effects, making them an anatomical niche for invading M. tuberculosis . RPE cells exhibit high tolerance to environmental redox stresses, allowing phagocytosed M. tuberculosis bacilli to maintain viability in a dormant state. However, the microbiological and metabolic mechanisms determining the interaction between the RPE intracellular environment and phagocytosed M. tuberculosis are largely unknown. Here, liquid chromatography-mass spectrometry metabolomics were used to illuminate the metabolic state within RPE cells reprogrammed to harbor dormant M. tuberculosis bacilli and enhance antibiotic tolerance. Timely and accurate diagnosis as well as efficient chemotherapies are crucial in preventing the poor visual outcomes of OTB patients. Unfortunately, the efficacy of current methods is highly limited. Thus, the results will lead to propose a novel therapeutic option to synthetically kill the dormant M. tuberculosis inside the RPE cells by modulating the phenotypic state of M. tuberculosis and laying the foundation for a new, innovative regimen for treating OTB., Importance: Understanding the metabolic environment within the retinal pigment epithelium (RPE) cells altered by infection with Mycobacterium tuberculosis and mycobacterial dormancy is crucial to identify new therapeutic methods to cure ocular tuberculosis. The present study showed that RPE cellular metabolism is altered to foster intracellular M. tuberculosis to enter into the dormant and drug-tolerant state, thereby blunting the efficacy of anti-tuberculosis chemotherapy. RPE cells serve as an anatomical niche as the cells protect invading bacilli from antibiotic treatment. LC-MS metabolomics of RPE cells after co-treatment with H 2 O 2 and M. tuberculosis infection showed that the intracellular environment within RPE cells is enriched with a greater level of oxidative stress. The antibiotic tolerance of intracellular M. tuberculosis within RPE cells can be restored by a metabolic manipulation strategy such as co-treatment of antibiotic with the most downstream glycolysis metabolite, phosphoenolpyruvate., Competing Interests: The authors declare no conflict of interest.