Publications by authors named "Jacob Garza"

As costs of higher education continue to rise, textbook pur¬chase is an area in which students have control over spending. The purposes of this project were to: 1) describe textbook use among current students and recent graduates in one physical therapist program, and 2) determine how this information might be utilized in addressing faculty textbook decisions in entry-level education. Electronic surveys were sent to 83 students and 229 graduates of a Doctor of Physical Therapy program in Texas.

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Bipolar disorder (BD) is a highly heritable mood disorder with intermittent episodes of mania and depression. Lithium is the first-in-line medication to treat BD, but it is only effective in a subset of individuals. Large-scale human genomic studies have repeatedly linked the ANK3 gene (encoding ankyrin-G, AnkG) to BD.

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Frontotemporal dementia (FTD) because of MAPT mutation causes pathological accumulation of tau and glutamatergic cortical neuronal death by unknown mechanisms. We used human induced pluripotent stem cell (iPSC)-derived cerebral organoids expressing tau-V337M and isogenic corrected controls to discover early alterations because of the mutation that precede neurodegeneration. At 2 months, mutant organoids show upregulated expression of MAPT, glutamatergic signaling pathways, and regulators, including the RNA-binding protein ELAVL4, and increased stress granules.

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  • Adiponectin, a hormone from fat cells, influences behaviors related to depression by acting on specific receptors in the brain, particularly in serotonin (5-HT) neurons.
  • The deletion of adiponectin receptor 1 (AdipoR1) in these neurons leads to symptoms of depression, such as reduced pleasure-seeking and increased despair, with varying effects observed between male and female mice.
  • Changes in serotonin levels and transport were noted in the brains of male mice lacking AdipoR1, suggesting that adiponectin plays a crucial role in 5-HT signaling and its associated behaviors, which may differ based on sex.
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The ankyrin 3 gene (ANK3) is a well-established risk gene for psychiatric illness, but the mechanisms underlying its pathophysiology remain elusive. We examined the molecular effects of disrupting brain-specific Ank3 isoforms in mouse and neuronal model systems. RNA sequencing of hippocampus from Ank3+/- and Ank3+/+ mice identified altered expression of 282 genes that were enriched for microtubule-related functions.

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Adiponectin, a metabolic hormone secreted by adipocytes, can cross the blood-brain barrier to act on neurons in different brain regions, including those involved in stress-related disorders. Here we show that dopamine neurons in the ventral tegmental area (VTA) express adiponectin receptor 1 (AdipoR1). Intra-VTA infusion of adiponectin or the adiponectin mimetic AdipoRon in wild-type mice decreases basal dopamine neuron population activity and firing rate and reverses the restraint stress-induced increase in dopamine neuron activity and anxiety behavior.

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Current medications for depression typically require weeks of treatment before significant clinical improvement is observed, and are only effective in a relatively small subset of patients. Recent human clinical studies have demonstrated that ketamine, an NMDA receptor antagonist, and scopolamine, a muscarinic acetylcholine receptor antagonist, produce rapid antidepressant responses within hours of administration, and are effective in treatment-resistant patients. We hypothesize that efficacy and tolerability may be improved by combining lower doses of both drugs in the treatment of depression.

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Previous studies have demonstrated that leptin and its receptors (LepRb) in the central nervous system play an important role in regulating depression- and anxiety-related behaviours. However, the physiological functions of LepRb in specific brain regions for mediating different emotional behaviours remain to be defined. In this study, we examined the behavioural effects of LepRb ablation in the adult hippocampus using a series of behavioural paradigms for assessing depression- and anxiety-related behaviours.

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The glutamatergic system has been implicated in the pathophysiology of depression and the mechanism of action of antidepressants. Leptin, an adipocyte-derived hormone, has antidepressant-like properties. However, the functional role of leptin receptor (Lepr) signaling in glutamatergic neurons remains to be elucidated.

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  • The melanocortin-4 receptor (MC4R) in the medial amygdala (MeA) plays a critical role in anxiety and stress responses, as its activation increases anxiety-like behavior and decreases food intake.
  • Acute stress activates MC4R-expressing neurons in the MeA, leading to changes in behavior and hormone levels, specifically increasing corticosterone.
  • Blockade of MC4R in the MeA counteracts these anxiety and appetite effects caused by stress, indicating that MC4R signaling is important for managing emotional stress responses.
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Human depression is associated with cognitive deficits. It is critical to have valid animal models in order to investigate mechanisms and treatment strategies for these associated conditions. The goal of this study was to determine the association of cognitive dysfunction with depression-like behaviour in an animal model of depression and investigate the neural circuits underlying the behaviour.

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Rationale: Our previous studies in rats have shown that the adipocyte-derived hormone leptin induces antidepressant-like effects with a behavioral profile similar to selective serotonin reuptake inhibitor (SSRI) antidepressants. Acute SSRI treatment causes paradoxical anxiogenic responses, although chronic treatment has therapeutic effects on anxiety. However, the role of leptin in anxiety remains to be established.

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Pharmacological and genetic studies have suggested that melanocortin-4 receptor (MC4R) signaling in the paraventricular nucleus of hypothalamus (PVN) regulates appetite and energy balance. However, the specific role of MC4R signaling in PVN neurons in these processes remains to be further elucidated in normally developed animals. In the present study, we employed RNA interference to determine whether MC4R knockdown in the PVN modulates food intake and body weight in adult rats.

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  • Leptin, a hormone produced by fat cells, influences neurogenesis (the formation of new neurons) in the hippocampus of adult mice.
  • Chronic leptin administration increases the proliferation of hippocampal progenitor cells, but doesn't significantly affect their differentiation or survival.
  • Leptin activates specific signaling pathways (Akt and STAT3), which are crucial for promoting the proliferation of these cells, as shown by the reduced proliferation when these pathways are inhibited.
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Nearly all neurodegenerative diseases are associated with abnormal accumulation of ubiquitin (Ub) conjugates within neuronal inclusion bodies. To directly test the hypothesis that depletion of cellular Ub is sufficient to cause neurodegeneration, we have disrupted Ubb, one of four genes that supply Ub in the mouse. Here, we report that loss of Ubb led to a progressive degenerative disorder affecting neurons within the arcuate nucleus of the hypothalamus.

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Neurons producing melanocortin receptor agonist, alpha-MSH derived from proopiomelanocortin, and antagonist, agouti-related protein, are known to be sensitive to metabolic stress such as food deprivation and glucoprivation. However, how these neurons respond to emotional/psychological stress remained to be elucidated. We report here that acute emotional stressors, i.

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