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Sayegh FJP, Mouledous L, Macri C, Pi Macedo J, Lejards C, Rampon C, Verret L, Dahan L. Ventral tegmental area dopamine projections to the hippocampus trigger long-term potentiation and contextual learning. Nat Commun 2024; 15:4100. [PMID: 38773091 PMCID: PMC11109191 DOI: 10.1038/s41467-024-47481-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 03/28/2024] [Indexed: 05/23/2024] Open
Abstract
In most models of neuronal plasticity and memory, dopamine is thought to promote the long-term maintenance of Long-Term Potentiation (LTP) underlying memory processes, but not the initiation of plasticity or new information storage. Here, we used optogenetic manipulation of midbrain dopamine neurons in male DAT::Cre mice, and discovered that stimulating the Schaffer collaterals - the glutamatergic axons connecting CA3 and CA1 regions - of the dorsal hippocampus concomitantly with midbrain dopamine terminals within a 200 millisecond time-window triggers LTP at glutamatergic synapses. Moreover, we showed that the stimulation of this dopaminergic pathway facilitates contextual learning in awake behaving mice, while its inhibition hinders it. Thus, activation of midbrain dopamine can operate as a teaching signal that triggers NeoHebbian LTP and promotes supervised learning.
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Affiliation(s)
- Fares J P Sayegh
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, Toulouse, France.
| | - Lionel Mouledous
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, Toulouse, France
| | - Catherine Macri
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, Toulouse, France
| | - Juliana Pi Macedo
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, Toulouse, France
| | - Camille Lejards
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, Toulouse, France
| | - Claire Rampon
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, Toulouse, France
| | - Laure Verret
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, Toulouse, France
| | - Lionel Dahan
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, Toulouse, France.
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Wang Y, Zhou Y, Li G, Qin P, Wang J, Qi L, Li L, Wang Y, Wang J, Li J, Liang Z, Zhou Y. Executive functions in non-suicidal self-injury comorbid first-episode and drug-naïve depression among adolescents. Psychiatry Res 2023; 328:115476. [PMID: 37708804 DOI: 10.1016/j.psychres.2023.115476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 09/07/2023] [Accepted: 09/09/2023] [Indexed: 09/16/2023]
Abstract
Executive functions(EFs) may be associated with the emergence of non-suicidal self-injury(NSSI) due to their role as behavior controllers. EFs includes three core cognitive processes: inhibitory control, working memory, and cognitive flexibility(i.e. the ability to selectively alter cognitive strategies to generate appropriate behavior in the changing environment). This study aimed to systematically explore the three core EFs in depressed adolescents with NSSI. The data was obtained from the baseline data of the Chinese adolescent depression Cohort. The adolescents underwent cognitive assessments to yield domain-specific scores in EFs using the Digit Span Backward test(DSB), the Stroop Color-word interference test- color-word condition(Stroop-CW), and the Wisconsin Card Sorting tests(WCST). The significant differences in WCST scores were found between the NSSI group and the non-NSSI group. NSSI frequency was moderately positively correlated with total errors and negatively correlated with the number of categories completed. The number of categories completed in the "≥200″ NSSI frequency group was significantly lower than that in the "≤10″ NSSI group. The current findings suggested that depressed adolescents who had engaged in NSSI have poorer cognitive flexibility performance compared to adolescents without NSSI. As the frequency of NSSI increased, cognitive flexibility might become worse. These results provide evidence of a connection between executive dysfunctions and NSSI in depressed adolescents.
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Affiliation(s)
- Yanni Wang
- School of Public Health, Lanzhou University, Lanzhou, China
| | - Yue Zhou
- School of Public Health, Lanzhou University, Lanzhou, China
| | - Guohua Li
- Shenzhen Mental Health Center, Shenzhen Kangning Hospital, Shenzhen, China
| | - Peiwu Qin
- Tsinghua Shenzhen international graduate school, Shenzhen, China
| | - Jiesi Wang
- CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Ling Qi
- School of Health Science and Nursing, Wuhan Polytechnic University, Wuhan, China
| | - Linling Li
- School of Biomedical Engineering, Health Science Center, Shenzhen University, Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound Imaging Shenzhen, China
| | - Yang Wang
- College of Management, Shenzhen University, Shenzhen, China
| | - Jianhong Wang
- Shenzhen Mental Health Center, Shenzhen Kangning Hospital, Shenzhen, China
| | - Junchang Li
- Shenzhen Mental Health Center, Shenzhen Kangning Hospital, Shenzhen, China
| | - Zhen Liang
- School of Biomedical Engineering, Health Science Center, Shenzhen University, Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound Imaging Shenzhen, China
| | - Yongjie Zhou
- Shenzhen Mental Health Center, Shenzhen Kangning Hospital, Shenzhen, China.
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Anziano M, Mouthon M, Thoeny H, Sperber C, Spierer L. Mental flexibility depends on a largely distributed white matter network: Causal evidence from connectome-based lesion-symptom mapping. Cortex 2023; 165:38-56. [PMID: 37253289 DOI: 10.1016/j.cortex.2023.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 10/20/2022] [Accepted: 04/06/2023] [Indexed: 06/01/2023]
Abstract
Mental flexibility (MF) refers to the capacity to dynamically switch from one task to another. Current neurocognitive models suggest that since this function requires interactions between multiple remote brain areas, the integrity of the anatomic tracts connecting these brain areas is necessary to maintain performance. We tested this hypothesis by assessing with a connectome-based lesion-symptom mapping approach the effects of white matter lesions on the brain's structural connectome and their association with performance on the trail making test, a neuropsychological test of MF, in a sample of 167 first unilateral stroke patients. We found associations between MF deficits and damage of i) left lateralized fronto-temporo-parietal connections and interhemispheric connections between left temporo-parietal and right parietal areas; ii) left cortico-basal connections; and iii) left cortico-pontine connections. We further identified a relationship between MF and white matter disconnections within cortical areas composing the cognitive control, default mode and attention functional networks. These results for a central role of white matter integrity in MF extend current literature by providing causal evidence for a functional interdependence among the regional cortical and subcortical structures composing the MF network. Our results further emphasize the necessity to consider connectomics in lesion-symptom mapping analyses to establish comprehensive neurocognitive models of high-order cognitive functions.
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Affiliation(s)
- Marco Anziano
- Laboratory for Neurorehabilitation Science, Medicine Section, Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland.
| | - Michael Mouthon
- Laboratory for Neurorehabilitation Science, Medicine Section, Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Harriet Thoeny
- Department of Diagnostic and Interventional Radiology, Cantonal Hospital of Fribourg, University of Fribourg, Fribourg, Switzerland
| | - Christoph Sperber
- Department of Neurology, Inselspital, University Hospital Bern, Bern, Switzerland
| | - Lucas Spierer
- Laboratory for Neurorehabilitation Science, Medicine Section, Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland
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Palumbo TB, Miwa JM. Lynx1 and the family of endogenous mammalian neurotoxin-like proteins and their roles in modulating nAChR function. Pharmacol Res 2023; 194:106845. [PMID: 37437646 DOI: 10.1016/j.phrs.2023.106845] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 06/28/2023] [Accepted: 06/29/2023] [Indexed: 07/14/2023]
Abstract
The promise of nicotinic receptors as a therapeutic target has yet to be fully realized, despite solid data supporting their involvement in neurological and neuropsychiatric diseases. The reasons for this are likely complex and manifold, having to do with the widespread action of the cholinergic system and the biophysical mechanism of action of nicotinic receptors leading to fast desensitization and down-regulation. Conventional drug development strategies tend to focus on receptor subtype-specific action of candidate therapeutics, although the broad agonist, nicotine, is being explored in the clinic. The potential negative effects of nicotine make the search for alternate strategies warranted. Prototoxins are a promising yet little-explored avenue of nicotinic receptor drug development. Nicotinic receptors in the brain belong to a complex of proteins, including those that bind to the extracellular face of the receptor, as well as chaperones that bind the intracellular domain, etc. Lynx prototoxins have allosteric modularity effects on receptor function and number and have been implicated in complex in vivo processes such as neuroplasticity, learning, and memory. Their mechanism of action and binding specificity on sets of nAChR subtypes present intriguing possibilities for more efficacious and nuanced therapeutic targeting than nicotinic receptor subtypes alone. An allosteric drug may restrict its actions to physiologically relevant time points, which tend to be correlated with salient events which would be encoded into long-term memory storage. Rather than blanketing the brain with a steady and prolonged elevation of agonist, an allosteric nAChR compound could avoid side effects and loss of efficacy over time. This review details the potential strengths and challenges of prototoxin proteins as therapeutic targets, and some of the utility of such therapeutics based on the emerging understanding of cholinergic signaling in a growing number of complex neural processes.
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Affiliation(s)
- Talulla B Palumbo
- Department of Biological Sciences, Lehigh University, 111 Research Dr., Iacocca Hall, B-217, Bethlehem PA, USA.
| | - Julie M Miwa
- Department of Biological Sciences, Lehigh University, 111 Research Dr., Iacocca Hall, B-217, Bethlehem PA, USA.
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Perez S, Cui Y, Vignoud G, Perrin E, Mendes A, Zheng Z, Touboul J, Venance L. Striatum expresses region-specific plasticity consistent with distinct memory abilities. Cell Rep 2022; 38:110521. [PMID: 35294877 DOI: 10.1016/j.celrep.2022.110521] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 12/23/2021] [Accepted: 02/21/2022] [Indexed: 11/24/2022] Open
Abstract
The striatum mediates two learning modalities: goal-directed behavior in dorsomedial (DMS) and habits in dorsolateral (DLS) striata. The synaptic bases of these learnings are still elusive. Indeed, while ample research has described DLS plasticity, little remains known about DMS plasticity and its involvement in procedural learning. Here, we find symmetric and asymmetric anti-Hebbian spike-timing-dependent plasticity (STDP) in DMS and DLS, respectively, with opposite plasticity dominance upon increasing corticostriatal activity. During motor-skill learning, plasticity is engaged in DMS and striatonigral DLS neurons only during early learning stages, whereas striatopallidal DLS neurons are mobilized only during late phases. With a mathematical modeling approach, we find that symmetric anti-Hebbian STDP favors memory flexibility, while asymmetric anti-Hebbian STDP favors memory maintenance, consistent with memory processes at play in procedural learning.
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Affiliation(s)
- Sylvie Perez
- Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS, INSERM, Université PSL, Paris, France
| | - Yihui Cui
- Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS, INSERM, Université PSL, Paris, France; Department of Neurobiology, Department of Neurology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Gaëtan Vignoud
- Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS, INSERM, Université PSL, Paris, France; MAMBA-Modelling and Analysis for Medical and Biological Applications, Inria Paris, LJLL (UMR-7598) -Laboratory Jacques-Louis Lions, Paris, France
| | - Elodie Perrin
- Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS, INSERM, Université PSL, Paris, France
| | - Alexandre Mendes
- Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS, INSERM, Université PSL, Paris, France
| | - Zhiwei Zheng
- Department of Neurobiology, Department of Neurology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Jonathan Touboul
- Department of Mathematics and Volen National Center for Complex Systems, Brandeis University, Waltham, MA, USA
| | - Laurent Venance
- Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS, INSERM, Université PSL, Paris, France.
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Sherafat Y, Chen E, Lallai V, Bautista M, Fowler JP, Chen YC, Miwa J, Fowler CD. Differential Expression Patterns of Lynx Proteins and Involvement of Lynx1 in Prepulse Inhibition. Front Behav Neurosci 2021; 15:703748. [PMID: 34803621 PMCID: PMC8595198 DOI: 10.3389/fnbeh.2021.703748] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 09/29/2021] [Indexed: 11/20/2022] Open
Abstract
Negative allosteric modulators, such as lynx1 and lynx2, directly interact with nicotinic acetylcholine receptors (nAChRs). The nAChRs are integral to cholinergic signaling in the brain and have been shown to mediate different aspects of cognitive function. Given the interaction between lynx proteins and these receptors, we examined whether these endogenous negative allosteric modulators are involved in cognitive behaviors associated with cholinergic function. We found both cell-specific and overlapping expression patterns of lynx1 and lynx2 mRNA in brain regions associated with cognition, learning, memory, and sensorimotor processing, including the prefrontal cortex (PFC), cingulate cortex, septum, hippocampus, amygdala, striatum, and pontine nuclei. Since lynx proteins are thought to play a role in conditioned associations and given the expression patterns across brain regions, we first assessed whether lynx knockout mice would differ in a cognitive flexibility task. We found no deficits in reversal learning in either the lynx1–/– or lynx2–/– knockout mice. Thereafter, sensorimotor gating was examined with the prepulse inhibition (PPI) assessment. Interestingly, we found that both male and female lynx1–/– mice exhibited a deficit in the PPI behavioral response. Given the comparable expression of lynx2 in regions involved in sensorimotor gating, we then examined whether removal of the lynx2 protein would lead to similar behavioral effects. Unexpectedly, we found that while male lynx2–/– mice exhibited a decrease in the baseline startle response, no differences were found in sensorimotor gating for either male or female lynx2–/– mice. Taken together, these studies provide insight into the expression patterns of lynx1 and lynx2 across multiple brain regions and illustrate the modulatory effects of the lynx1 protein in sensorimotor gating.
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Affiliation(s)
- Yasmine Sherafat
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Edison Chen
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Valeria Lallai
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Malia Bautista
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - James P Fowler
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Yen-Chu Chen
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Julie Miwa
- Department of Biological Sciences, Lehigh University, Bethlehem, PA, United States
| | - Christie D Fowler
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
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Boender AJ, Bontempi L, Nava L, Pelloux Y, Tonini R. Striatal Astrocytes Shape Behavioral Flexibility via Regulation of the Glutamate Transporter EAAT2. Biol Psychiatry 2021; 89:1045-1057. [PMID: 33516457 DOI: 10.1016/j.biopsych.2020.11.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 10/21/2020] [Accepted: 11/13/2020] [Indexed: 12/31/2022]
Abstract
BACKGROUND Striatal circuits must be modulated for behavioral flexibility, the ability to adapt to environmental changes. Striatal astrocytes contribute to circuit neuromodulation by controlling the activity of ambient neurotransmitters. In particular, extracellular glutamate levels are tightly controlled by the astrocytic glutamate transporter EAAT2, influencing synaptic functioning and neural network activity. However, it remains unclear if EAAT2 responds to environmental cues to specifically shape action control. METHODS To investigate the relationship between behavioral flexibility and experience-dependent regulation of EAAT2 expression in the dorsal striatum, mice were trained on an instrumental task. We manipulated EAAT2 expression using chemogenetic activation of astrocytic Gq signaling or in vivo morpholinos and determined the ability to adapt to novel environmental contingencies. RESULTS The loss of behavioral flexibility with task overtraining is associated with the upregulation of EAAT2, which results in enhanced glutamate clearance and altered modulation of glutamatergic neurotransmission in the lateral part of the dorsal striatum. Interfering with EAAT2 upregulation in this striatal area preserves behavioral flexibility. CONCLUSIONS Astrocytes are emerging as critical regulators of striatal functions. This work demonstrates that plasticity of EAAT2 expression in the lateral part of the dorsal striatum shapes behavior, thus providing novel mechanistic insights into how flexibility in action control is regulated.
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Affiliation(s)
- Arjen J Boender
- Neuromodulation of Cortical and Subcortical Circuits Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
| | - Leonardo Bontempi
- Neuromodulation of Cortical and Subcortical Circuits Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
| | - Luca Nava
- Neuromodulation of Cortical and Subcortical Circuits Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
| | - Yann Pelloux
- Neuromodulation of Cortical and Subcortical Circuits Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
| | - Raffaella Tonini
- Neuromodulation of Cortical and Subcortical Circuits Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy.
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Walters JL, Chelonis JJ, Fogle CM, Ferguson SA, Sarkar S, Paule MG, Talpos JC. Acetyl-l-carnitine does not prevent neurodegeneration in a rodent model of prolonged neonatal anesthesia. Neurotoxicol Teratol 2020; 80:106891. [PMID: 32376384 DOI: 10.1016/j.ntt.2020.106891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 04/27/2020] [Accepted: 04/29/2020] [Indexed: 12/12/2022]
Abstract
Many studies have shown that prolonged or repeated use of general anesthesia early in life can cause an increase in neurodegeneration and lasting changes in behavior. While short periods of general anesthesia appear to be safe, there is a concern about the neurotoxic potential of prolonged or repeated general anesthesia in young children. Unfortunately, the use of general anesthesia in children cannot be avoided. It would be a great benefit to develop a strategy to reduce or reverse anesthesia mitigated neurotoxicity. The mechanisms behind anesthesia related neurotoxicity are unknown, but evidence suggests that mitochondrial dysfunction and abnormal energy utilization are involved. Recent research suggests that a class of compounds known as carnitines may be effective at preventing anesthesia related neurotoxicity by influencing fatty acid metabolism in the mitochondria. However, it is unknown if carnitines can provide protection against changes in behavior associated with early life exposure to anesthesia. Accordingly, we evaluated the neuroprotective potential of acetyl-l-carnitine in 7-day old rats. Rat pups were exposed to 6 h of general anesthesia with sevoflurane or a control condition, with and without acetyl-l-carnitine. The oxygenation level of animals was continuously monitored during sevoflurane exposure, and any animal showing signs of hypoxia was removed from the study. Animals exposed to sevoflurane showed clear signs of neurodegeneration 2 h after sevoflurane exposure. The hippocampus, cortex, thalamus, and caudate putamen all had elevated levels of Fluoro-Jade C staining. Despite the elevated levels of Fluoro-Jade C, few behavioral changes were observed in an independent cohort of animals treated with sevoflurane. Furthermore, acetyl-l-carnitine had little impact on levels of Fluoro-Jade C staining in animals treated with sevoflurane. These data suggest that acetyl-l-carnitine may offer little protection again anesthesia related neurotoxicity in fully oxygenated animals.
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Abstract
Background:Tics, defined as quick, rapid, sudden, recurrent, non-rhythmic motor movements or vocalizations are required components of Tourette Syndrome (TS) - a complex disorder characterized by the presence of fluctuating, chronic motor and vocal tics, and the presence of co-existing neuropsychological problems. Despite many advances, the underlying pathophysiology of tics/TS remains unknown.Objective:To address a variety of controversies surrounding the pathophysiology of TS. More specifically: 1) the configuration of circuits likely involved; 2) the role of inhibitory influences on motor control; 3) the classification of tics as either goal-directed or habitual behaviors; 4) the potential anatomical site of origin, e.g. cortex, striatum, thalamus, cerebellum, or other(s); and 5) the role of specific neurotransmitters (dopamine, glutamate, GABA, and others) as possible mechanisms (Abstract figure).Methods:Existing evidence from current clinical, basic science, and animal model studies are reviewed to provide: 1) an expanded understanding of individual components and the complex integration of the Cortico-Basal Ganglia-Thalamo-Cortical (CBGTC) circuit - the pathway involved with motor control; and 2) scientific data directly addressing each of the aforementioned controversies regarding pathways, inhibition, classification, anatomy, and neurotransmitters.Conclusion:Until a definitive pathophysiological mechanism is identified, one functional approach is to consider that a disruption anywhere within CBGTC circuitry, or a brain region inputting to the motor circuit, can lead to an aberrant message arriving at the primary motor cortex and enabling a tic. Pharmacologic modulation may be therapeutically beneficial, even though it might not be directed toward the primary abnormality.
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Affiliation(s)
- Harvey S. Singer
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, United States
| | - Farhan Augustine
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, United States
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