Publications

@article{pmid32523515,

title = {Ultradian Secretion of Growth Hormone in Mice: Linking Physiology With Changes in Synapse Parameters Using Super-Resolution Microscopy},

author = {Klaudia Bednarz and Walaa Alshafie and Sarah Aufmkolk and Théotime Desserteaux and Pratap Singh Markam and Kai-Florian Storch and Thomas Stroh},

doi = {10.3389/fncir.2020.00021},

issn = {1662-5110},

year  = {2020},

date = {2020-01-01},

journal = {Front Neural Circuits},

volume = {14},

pages = {21},

abstract = {Neuroendocrine circuits are orchestrated by the pituitary gland in response to hypothalamic hormone-releasing and inhibiting factors to generate an ultradian and/or circadian rhythm of hormone secretion. However, mechanisms that govern this rhythmicity are not fully understood. It has been shown that synaptic transmission in the rodent hypothalamus undergoes cyclical changes in parallel with rhythmic hormone secretion and a growing body of evidence suggests that rapid rewiring of hypothalamic neurons may be the source of these changes. For decades, structural synaptic studies have been utilizing electron microscopy, which provides the resolution suitable for visualizing synapses. However, the small field of view, limited specificity and manual analysis susceptible to bias fuel the search for a more quantitative approach. Here, we apply the fluorescence super-resolution microscopy approach  Stochastic Optical Reconstruction Microscopy (STORM) to quantify and structurally characterize excitatory and inhibitory synapses that contact growth hormone-releasing-hormone (GHRH) neurons during peak and trough values of growth hormone (GH) concentration in mice. This approach relies on a three-color immunofluorescence staining of GHRH and pre- and post-synaptic markers, and a quantitative analysis with a Density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm. With this method we confirm our previous findings, using electron microscopy, of increased excitatory synaptic input to GHRH neurons during peak levels of GH. Additionally, we find a shift in synapse numbers during low GH levels, where more inhibitory synaptic inputs are detected. Lastly, we utilize STORM to study novel aspects of synaptic structure. We show that more excitatory (but not inhibitory) pre-synaptic clusters associate with excitatory post-synaptic clusters during peaks of GH secretion and that the numbers of post-synaptic clusters increase during high hormone levels. The results presented here provide an opportunity to highlight STORM as a valuable quantitative approach to study synaptic structure in the neuroendocrine circuit. Importantly, our analysis of GH circuitry sheds light on the potential mechanism that drives ultradian changes in synaptic transmission and possibly aids in GH pulse generation in mice.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32520164,

title = {Childhood-maltreatment subtypes in bipolar patients with suicidal behavior: systematic review and meta-analysis},

author = {Dante Duarte and Raoul Belzeaux and Bruno Etain and Kyle T Greenway and Emilie Rancourt and Humberto Correa and Gustavo Turecki and Stéphane Richard-Devantoy},

doi = {10.1590/1516-4446-2019-0592},

issn = {1809-452X},

year  = {2020},

date = {2020-01-01},

journal = {Braz J Psychiatry},

volume = {42},

number = {5},

pages = {558--567},

abstract = {OBJECTIVE: Patients with bipolar disorders have a high risk of suicidal behavior. Childhood maltreatment is a well-established risk factor for suicidal behavior. The objective of this study was to examine the association between childhood-maltreatment subtypes and vulnerability to suicide attempts in bipolar disorder using the Childhood Trauma Questionnaire (CTQ).nnMETHODS: A literature review was performed using the MEDLINE, Embase, and PsycINFO databases. Thirteen studies met the selection criteria. In the meta-analysis, the Childhood Trauma Questionnaire (CTQ) was used to assess a wide range of childhood maltreatment subtypes, which were analyzed by using a random-effects model to account for the likely variations of true effect sizes between the included studies.nnRESULTS: In the systematic review, 13 studies met the selection criteria. The CTQ was selected for the meta-analysis to increase the homogeneity of assessment and to encompass a wide range of childhood-maltreatment subtypes. The data were analyzed using a random-effects model. Compared to bipolar non-attempters, bipolar suicide attempters had experienced childhood maltreatment with a significantly higher frequency and had higher total CTQ scores (Hedges' g = -0.38, 95%CI -0.52 to -0.24, z = -5.27, p < 0.001) and CTQ sub-scores (sexual abuse: g = -0.39, 95%CI -0.52 to -0.26, z = -5.97; physical abuse: g = -0.26, 95%CI -0.39 to -0.13, z = -4.00; emotional abuse: g = -0.39, 95%CI -0.65 to -0.13, z = -2.97; physical neglect: g = -0.18, 95%CI -0.31 to -0.05, z = -2.79; emotional neglect: g = -0.27, 95%CI -0.43 to -0.11, z = -3.32).nnCONCLUSIONS: Childhood maltreatment, as assessed by the CTQ, may contribute to an increased risk of suicidal behavior among people with bipolar disorders. Recognizing maltreatment as an etiological risk factor is a crucial step toward furthering science-based preventive psychiatry.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32499681,

title = {A Probabilistic Framework for Decoding Behavior From  Calcium Imaging Data},

author = {Guillaume Etter and Frederic Manseau and Sylvain Williams},

doi = {10.3389/fncir.2020.00019},

issn = {1662-5110},

year  = {2020},

date = {2020-01-01},

journal = {Front Neural Circuits},

volume = {14},

pages = {19},

abstract = {Understanding the role of neuronal activity in cognition and behavior is a key question in neuroscience. Previously,  studies have typically inferred behavior from electrophysiological data using probabilistic approaches including Bayesian decoding. While providing useful information on the role of neuronal subcircuits, electrophysiological approaches are often limited in the maximum number of recorded neurons as well as their ability to reliably identify neurons over time. This can be particularly problematic when trying to decode behaviors that rely on large neuronal assemblies or rely on temporal mechanisms, such as a learning task over the course of several days. Calcium imaging of genetically encoded calcium indicators has overcome these two issues. Unfortunately, because calcium transients only indirectly reflect spiking activity and calcium imaging is often performed at lower sampling frequencies, this approach suffers from uncertainty in exact spike timing and thus activity frequency, making rate-based decoding approaches used in electrophysiological recordings difficult to apply to calcium imaging data. Here we describe a probabilistic framework that can be used to robustly infer behavior from calcium imaging recordings and relies on a simplified implementation of a naive Baysian classifier. Our method discriminates between periods of activity and periods of inactivity to compute probability density functions (likelihood and posterior), significance and confidence interval, as well as mutual information. We next devise a simple method to decode behavior using these probability density functions and propose metrics to quantify decoding accuracy. Finally, we show that neuronal activity can be predicted from behavior, and that the accuracy of such reconstructions can guide the understanding of relationships that may exist between behavioral states and neuronal activity.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32491041,

title = {Brazilian research on child and adolescent suicide: looking at the past to plan the future},

author = {Massimiliano Orri and Gustavo Turecki},

doi = {10.1590/1516-4446-2020-1024},

issn = {1809-452X},

year  = {2020},

date = {2020-01-01},

journal = {Braz J Psychiatry},

volume = {42},

number = {5},

pages = {570--572},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32474466,

title = {APOE4 Status is Related to Differences in Memory-Related Brain Function in Asymptomatic Older Adults with Family History of Alzheimer's Disease: Baseline Analysis of the PREVENT-AD Task Functional MRI Dataset},

author = {Sheida Rabipour and Sricharana Rajagopal and Elsa Yu and Stamatoula Pasvanis and Marie-Elyse Lafaille-Magnan and John Breitner and  and M Natasha Rajah},

doi = {10.3233/JAD-191292},

issn = {1875-8908},

year  = {2020},

date = {2020-01-01},

journal = {J Alzheimers Dis},

volume = {76},

number = {1},

pages = {97--119},

abstract = {BACKGROUND: Episodic memory decline is one of the earliest symptoms of late-onset Alzheimer's disease (AD). Older adults with the apolipoprotein E ɛ4 (+APOE4) genetic risk factor for AD may exhibit altered patterns of memory-related brain activity years prior to initial symptom onset.nnOBJECTIVE: Here we report the baseline episodic memory task functional MRI results from the PRe-symptomatic EValuation of Experimental or Novel Treatments for Alzheimer's Disease cohort in Montreal, Canada, in which 327 healthy older adults were scanned within 15 years of their parent's conversion to AD.nnMETHODS: Volunteers were scanned as they encoded and retrieved object-location spatial source associations. The task was designed to discriminate between brain activity related to spatial source recollection and object-only (recognition) memory. We used multivariate partial least squares (PLS) to test the hypothesis that +APOE4 adults with family history of AD would exhibit altered patterns of brain activity in the recollection-related memory network, comprised of medial frontal, parietal, and medial temporal cortices, compared to APOE4 non-carriers (-APOE4). We also examined group differences in the correlation between event-related brain activity and memory performance.nnRESULTS: We found group similarities in memory performance and in task-related brain activity in the recollection network, but differences in brain activity-behavior correlations in ventral occipito-temporal, medial temporal, and medial prefrontal cortices during episodic encoding.nnCONCLUSION: These findings are consistent with previous literature on the influence of APOE4 on brain activity and provide new perspective on potential gene-based differences in brain-behavior relationships in people with first-degree family history of AD.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32405466,

title = {Low-cost conditioned place preference setup including video recording and analysis of behaviour},

author = {Philip Vassilev and Moataz Salim and Christina Popescu and Cecilia Flores and Giovanni Hernandez},

doi = {10.1016/j.mex.2020.100899},

issn = {2215-0161},

year  = {2020},

date = {2020-01-01},

journal = {MethodsX},

volume = {7},

pages = {100899},

abstract = {The conditioned place preference (CPP) paradigm is widely used in rodent research to test the rewarding and aversive properties of different stimuli. Despite its relative simplicity, commercially available CPP systems are often costly. Here we describe the construction of a CPP setup and a behavioral data analysis pipeline incorporating: • a CPP box which can be built in a single day by using widely available and affordable materials. • an open source computer system for data acquisition (based on Raspberry Pi). • a freely available behavioural analysis software. The behavioural analysis allows for measurement of both locomotor activity and time spent in a zone of interest. Including all components, our setup costs ~1/10 of the cost of the least expensive commercially available CPP boxes alone (not including data acquisition and analysis). We validated the setup by showing that a 4 mg/kg dose of amphetamine increases locomotor activity acutely in adolescent male mice and induces conditioned preference for the drug-paired compartment in the CPP test.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}