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Despite a great need for healthcare, unhoused individuals encounter significant barriers to utilizing public healthcare systems. Given the inequities in access to healthcare, accompanied by disabilities and health risks associated with homelessness, self-efficacy for self-care is particularly critical. As a primary purpose of this article, we describe a self-care intervention (Health Advocacy Behavioral Activation), which was implemented within a long-standing participatory community action research project for homeless shelters, and report evidence of the intervention's effectiveness in enhancing self-efficacy for self-care. Participants included 62 residents of the St. Vincent de Paul Gateway Shelter for Men (Dayton, Ohio). Shelter residents with disabilities and those without disability benefited approximately equally from the intervention and both showed statistically significant pre- to post-intervention improvements in self-efficacy for self-care. Recommendations for future research examining the effectiveness of the intervention are provided. As a secondary (supplementary) purpose, we report preliminary evidence of psychometric validation for a new instrument (Scale of Self-Efficacy for Self-Care), which was developed in service of our primary purpose (i.e., to examine the effects of intervention on self-efficacy for self-care) because a literature search did not identify an appropriate measure. Because this new instrument fills a void in the literature, we anticipate that it will be useful in practice and research, and so we delineate research recommendations for additional psychometric validation of this measure. Because of the barriers that unhoused people encounter with regard to access to healthcare in the community, self-care interventions provided (and evaluated) on-site (e.g., in homeless shelters) are necessary.
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Pessoas Mal Alojadas , Autocuidado , Autoeficácia , Humanos , Pessoas Mal Alojadas/psicologia , Masculino , Ohio , Feminino , Adulto , Pessoa de Meia-Idade , Pesquisa Participativa Baseada na Comunidade , Acessibilidade aos Serviços de Saúde , Psicometria , Pessoas com DeficiênciaRESUMO
Modulation of the endocannabinoid system (ECS) is a novel putative target for therapeutic intervention in depressive disorders. Altering concentrations of one of the principal endocannabinoids, N-arachidonoylethanolamine, also known as anandamide (AEA) can affect depressive-like behaviors through several mechanisms including anti-inflammatory, hormonal, and neural circuit alterations. Recently, isoflavonoids, a class of plant-derived compounds, have been of therapeutic interest given their ability to modulate the metabolism of the endogenous ligands of the ECS. To determine the therapeutic potential of isoflavonoids, we screened several candidate compounds (Genistein, Biochanin-A, and 7-hydroxyflavone) in silico to determine their binding properties with fatty acid amide hydrolase (FAAH), the primary degrative enzyme for AEA. We further validated the ability of these compounds to inhibit FAAH and determined their effects on depressive-like and locomotor behaviors in the forced swim test (FST) and open field test in male and female mice. We found that while genistein was the most potent FAAH inhibitor, 7-hydroxyflavone was most effective at reducing immobility time in the forced swim test. Finally, we measured blood corticosterone and prefrontal cortex AEA concentrations following the forced swim test and found that all tested compounds decreased corticosterone and increased AEA, demonstrating that isoflavonoids are promising therapeutic targets as FAAH inhibitors.
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Endocanabinoides , Genisteína , Amidoidrolases , Animais , Antidepressivos , Ácidos Araquidônicos , Corticosterona , Camundongos , Alcamidas Poli-InsaturadasRESUMO
An early inflammatory insult is the most recognized risk factor associated with neurodevelopmental psychiatric disorders, even more so than genetic variants. Notably, complement component 4 (C4), a molecule involved in inflammatory responses, has been strongly associated with schizophrenia (SZ) and its role in other neurodevelopmental disorders, such as autism (ASD), is an area of active investigation. However, while C4 in SZ has been implicated in the context of synaptic pruning, little is known about its neuroinflammatory role. The subventricular zone (SVZ) is a region heavily involved in neurodevelopment and neuroimmune interactions through the lifespan; thus, it is a region wherein C4 may play a vital role in disease pathology. Using in situ hybridization with radioactive riboprobes and RNAscope, we identified robust astrocytic expression of C4 in the SVZ and in the septum pellucidum. C4 was also expressed in ependyma, neurons, and Ki67+ progenitor cells. Examination of mRNA levels showed elevated C4 in both ASD and SZ, with higher expression in SZ compared to controls. Targeted transcriptomic analysis of inflammatory pathways revealed a strong association of complement system genes with SZ, and to a lesser extent, ASD, as well as generalized immune dysregulation without a strong association with known infectious pathways. Analysis of differentially expressed genes (DEGs) showed that ASD DEGs were enriched in adaptive immune system functions such as Th cell differentiation, while SZ DEGs were enriched in innate immune system functions, including NF-κB and toll like receptor signaling. Moreover, the number of Ki67+ cells was significantly higher in ASD compared to SZ and controls. Taken together, these results support a role for C4 into inflammatory-neuroimmune dysregulation observed in SZ and ASD pathology.
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Transtorno do Espectro Autista , Complemento C4 , Esquizofrenia , Transtorno do Espectro Autista/genética , Complemento C4/metabolismo , Humanos , Antígeno Ki-67/metabolismo , Ventrículos Laterais/patologia , NF-kappa B/metabolismo , RNA MensageiroRESUMO
We show that the sex of human experimenters affects mouse behaviors and responses following administration of the rapid-acting antidepressant ketamine and its bioactive metabolite (2R,6R)-hydroxynorketamine. Mice showed aversion to the scent of male experimenters, preference for the scent of female experimenters and increased stress susceptibility when handled by male experimenters. This human-male-scent-induced aversion and stress susceptibility was mediated by the activation of corticotropin-releasing factor (CRF) neurons in the entorhinal cortex that project to hippocampal area CA1. Exposure to the scent of male experimenters before ketamine administration activated CA1-projecting entorhinal cortex CRF neurons, and activation of this CRF pathway modulated in vivo and in vitro antidepressant-like effects of ketamine. A better understanding of the specific and quantitative contributions of the sex of human experimenters to study outcomes in rodents may improve replicability between studies and, as we have shown, reveal biological and pharmacological mechanisms.
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Comportamento Animal , Ketamina , Pesquisadores , Caracteres Sexuais , Animais , Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Hormônio Liberador da Corticotropina/metabolismo , Feminino , Hipocampo/metabolismo , Humanos , Ketamina/farmacologia , Masculino , Camundongos , Neurônios/metabolismoRESUMO
OBJECTIVES: To examine the long-term adherence to serial imaging of patients with sporadic vestibular schwannoma and analyze factors associated with being lost to follow-up. STUDY DESIGN: Retrospective chart review with telephone interview. SETTING: Single tertiary care center. METHODS: Patients with a sporadic vestibular schwannoma and started on observational surveillance management between January 2005 and December 2010 were included. Demographic data, tumor size, hearing and vestibular changes, and follow-up length were recorded. Patient factors were analyzed for association with being lost to follow-up. RESULTS: In total, 122 patients were included with a median length of follow-up of 5 months (range, 0-146). After initial surveillance, 22.1% (n = 27) of patients had a change in management to either microsurgery or radiosurgery. Of the remaining 77.9% (n = 95), nearly half (44.2%, n = 42) never returned for a second visit, and all but 3 were eventually lost to follow-up. There was no association between sex, race, age at diagnosis, initial tumor size, insurance status, household income, or driving distance to hospital and being lost to follow-up. Of 26 interviewed patients initially lost to follow-up, 11 (42.3%) sought care at another institution, 5 (19.2%) chose to no longer receive care, 1 (3.8%) had transportation difficulties, and 9 (36.4%) had poor understanding of their diagnosis or instructions. CONCLUSIONS: The length of follow-up for patients undergoing surveillance of sporadic vestibular schwannoma varies widely, and patients are commonly lost to follow-up. Further efforts should be made to identify at-risk patients and provide adequate education to improve long-term surveillance.
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Hydroxynorketamines (HNKs) are formed in vivo after (R,S)-ketamine (ketamine) administration. The 12 HNK stereoisomers are distinguished by the position of cyclohexyl ring hydroxylation (at the 4, 5, or 6 position) and their unique stereochemistry at two stereocenters. Although HNKs were initially classified as inactive metabolites because of their lack of anesthetic effects, more recent studies have begun to reveal their biologic activities. In particular, (2R,6R)- and (2S 6)-HNK exert antidepressant-relevant behavioral and physiologic effects in preclinical models, which led to a rapid increase in studies seeking to clarify the mechanisms by which HNKs exert their pharmacological effects. To date, the majority of HNK research has focused on the actions of (2R,6R)-HNK because of its robust behavioral actions in tests of antidepressant effectiveness and its limited adverse effects. This review describes HNK pharmacokinetics and pharmacodynamics, as well as the putative cellular, molecular, and synaptic mechanisms thought to underlie their behavioral effects, both following their metabolism from ketamine and after direct administration in preclinical studies. Converging preclinical evidence indicates that HNKs modulate glutamatergic neurotransmission and downstream signaling pathways in several brain regions, including the hippocampus and prefrontal cortex. Effects on other neurotransmitter systems, as well as possible effects on neurotrophic and inflammatory processes, and energy metabolism, are also discussed. Additionally, the behavioral effects of HNKs and possible therapeutic applications are described, including the treatment of unipolar and bipolar depression, post-traumatic stress disorder, chronic pain, neuroinflammation, and other anti-inflammatory and analgesic uses. SIGNIFICANCE STATEMENT: Preclinical studies indicate that hydroxynorketamines (HNKs) exert antidepressant-relevant behavioral actions and may also have analgesic, anti-inflammatory, and other physiological effects that are relevant for the treatment of a variety of human diseases. This review details the pharmacokinetics and pharmacodynamics of the HNKs, as well as their behavioral actions, putative mechanisms of action, and potential therapeutic applications.
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Anestésicos , Ketamina , Antidepressivos/farmacologia , Depressão , Humanos , Ketamina/farmacologia , Transmissão SinápticaRESUMO
OBJECTIVE: Childhood maltreatment (CM) is a public health crisis that results in negative physical, mental health, and psychosocial (e.g., resource attainment) outcomes. Resource attainment is a critical outcome for marginalized populations, such as low-income African American women. This study addresses the gap in the literature regarding the association between CM and effectiveness of resource attainment and the potential mediating role of self-esteem in this association for African American women. METHOD: Data were gathered from a large public inner-city, university-affiliated health care system in the Southeastern United States. Participants selected were low-income African American women who have experienced intimate partner violence (IPV) and have attempted suicide in the prior year. The participants for this study completed the Childhood Trauma Questionnaire, the Beck Self-Esteem Scale, and the Effectiveness in Obtaining Resources Scale. RESULTS: Mediation analyses using bootstrapping with 213 women revealed the powerful role self-esteem plays in explaining the link between CM and resource attainment in low-income African American women. Specifically, overall CM and four of its subtypes (emotional abuse, physical abuse, emotional neglect, and physical neglect) were all associated with decreased resource attainment via the effect of decreased self-esteem. Sexual abuse was the only subtype of CM not significantly associated with self-esteem nor effectiveness of resource attainment. CONCLUSION: This research highlights the importance of screening for CM, its subtypes, and resource attainment in this population and bolstering self-esteem through psychological interventions to increase women's capacity to effectively secure necessary community resources. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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Maus-Tratos Infantis , Violência por Parceiro Íntimo , Negro ou Afro-Americano , Criança , Recursos Comunitários , Feminino , Humanos , AutoimagemRESUMO
The neurodevelopmental defects associated with ZIKV infections early in pregnancy are well documented, however the potential defects and long-term consequences associated with milder infections in late pregnancy and perinatal period are less well understood. To model these, we challenged 1 day old (P1) immunocompetent C57BL/6 mice with ZIKV. The animals developed a transient neurological syndrome including unsteady gait, kinetic tremors, severe ataxia and seizures 10-15 days post-infection (dpi) but symptoms subsided after a week, and most animals survived. Despite apparent recovery, MRI of convalescent mice show reduced cerebellar volume that correlates with altered coordination and motor function as well as hyperactivity and impulsivity. Persistent mRNA levels of pro-inflammatory genes including Cd80, Il-1α, and Ifn-γ together with Cd3, Cd8 and perforin (PrfA), suggested persistence of low-grade inflammation. Surprisingly, the brain parenchyma of convalescent mice harbor multiple small discrete foci with viral antigen, active apoptotic processes in neurons, and cellular infiltrates, surrounded by activated astrocytes and microglia as late as 1-year post-infection. Detection of negative-sense strand viral RNA and isolation of infectious virus derived from these convalescent mice by blinded passage in Vero cells confirmed long-term persistence of replicating ZIKV in CNS of convalescent mice. Although the infection appears to persist in defined reservoirs within CNS, the resulting inflammation could increase the risk of neurodegenerative disorders. This raises concern regarding possible long-term effects in asymptomatic children exposed to the virus and suggests that long-term neurological and behavioral monitoring as well as anti-viral treatment to clear virus from the CNS may be useful in patients exposed to ZIKV at an early age.
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Inflamação/fisiopatologia , Infecção por Zika virus/complicações , Infecção por Zika virus/fisiopatologia , Animais , Encéfalo/virologia , Chlorocebus aethiops , Modelos Animais de Doenças , Feminino , Inflamação/complicações , Camundongos , Camundongos Endogâmicos C57BL , Microcefalia/complicações , Microcefalia/virologia , Neurônios/virologia , Gravidez , Complicações Infecciosas na Gravidez/virologia , Células Vero , Zika virus/imunologia , Zika virus/metabolismo , Zika virus/patogenicidade , Infecção por Zika virus/virologiaRESUMO
A 33-year-old previously healthy Middle Eastern male presented to the emergency department with four weeks of progressively worsening fatigue, dyspnea on exertion, night sweats, and a 10-pound weight loss after suffering a self-limiting viral upper respiratory illness. He was found to be profoundly anemic and thrombocytopenic with normal white blood cell count with a lymphocytic predominance. His anemia was refractory to red blood cell transfusions, to which he developed hyperbilirubinemia. A CT scan revealed hepatomegaly and massive splenomegaly associated with multi-station abdominopelvic lymphadenopathy. A peripheral blood smear revealed several lymphocytes with hairy cell features and bone marrow biopsy revealed hypercellularity with interstitial infiltration by mature lymphoid cells. Flow cytometry confirmed the diagnosis of hairy cell leukemia (HCL) and this patient was initiated on cladribine chemotherapy. This case illustrates the uniqueness of this patient presenting within a short time course, at an atypical age, and with uncommon features for HCL including lymphadenopathy, hepatomegaly, and petechial skin rash. This case also highlights an important point regarding the management of severe anemia in the acute setting while undergoing splenic sequestration. His lack of response to red blood cell transfusions highlights the need for more research on the use of transfusions in patients who are not current surgical candidates for splenectomy.
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Psychological stress is known to have profound effects on immune function and to promote inflammatory conditions. Elevated circulating levels of cytokines associated with stress are known to increase the risk to several diseases, but little is known about this mechanism. This study assessed the role of T cells on cytokine levels after exposure to stress in the learned helplessness paradigm. Adoptive transfer of CD4+ T cells into Rag2-/- mice did not change cytokine levels to stress while CD8+ T cells resulted in an increase in TNF-α, IL-6 and IFN-γ in stressed Rag2-/- mice. Moreover, depletion of CD8+ T cells in WT mice abolished these cytokine responses to stress. Corticosterone and behavioral stress responsiveness was impaired in Rag2-/- mice reconstituted with CD8+ T cells. Notably, depletion of these cells in WT mice had no effect on behavior or corticosterone levels. Exposure to stress did not change the expression of canonical markers of T cell activation including CD62L and CD44 or modified intracellular cytokine content, suggesting that they are not the main producers of circulating cytokines in response to stress. These results show that CD8+ T cells promote TNF-α, IL-6 and IFN-γ responses to stress, possibly by stimulating non-lymphoid cells.
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Linfócitos T CD8-Positivos/imunologia , Citocinas/imunologia , Ativação Linfocitária , Estresse Psicológico/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Citocinas/genética , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/imunologia , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/imunologia , Selectina L/genética , Selectina L/imunologia , Camundongos , Camundongos Knockout , Estresse Psicológico/genética , Estresse Psicológico/patologiaRESUMO
Maternal immune activation (MIA) with the viral mimic poly I:C provides an established rodent model for studying schizophrenia (SZ) and other human neurodevelopmental disorders. Postnatal infections are additional risk factors in SZ and may cumulatively contribute to the emergence of pathophysiology. Underlying mechanisms may involve metabolites of the kynurenine pathway (KP) of tryptophan degradation, which is readily induced by inflammatory stimuli. Here we compared the expression of selected cytokines and KP enzymes, and the levels of selected KP metabolites, in the brain of MIA offspring following a second, acute immune challenge with lipopolysaccharides (LPS) on postnatal day (PND) 35 (adolescence) or PND 60 (early adulthood). Assessed in adolescence, MIA did not alter the expression of pro-inflammatory cytokines (except TNF-α) or KP metabolite levels compared to controls, but substantially reduced the expression of the anti-inflammatory cytokines IL-4 and IL-10 and influenced the expression of two of the four KP enzymes examined (IDO1 and TDO2). LPS treatment caused distinct changes in the expression of pro- and anti-inflammatory cytokines, as well as KP enzymes in MIA offspring, but had no effect on KP metabolites compared to control rats. Several of these effects were blunted in MIA offspring receiving LPS on PND 60. Notably, LPS caused a significant reduction in brain kynurenine levels in these animals. Of relevance for SZ-related hypotheses, these results indicate that MIA leads to an increasingly defective, rather than an overactive, immune regulation of cerebral KP metabolism during the postnatal period.
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Encéfalo/crescimento & desenvolvimento , Encéfalo/imunologia , Citocinas/metabolismo , Inflamação/metabolismo , Cinurenina/metabolismo , Efeitos Tardios da Exposição Pré-Natal/imunologia , Animais , Modelos Animais de Doenças , Feminino , Expressão Gênica/imunologia , Lipopolissacarídeos , Transtornos do Neurodesenvolvimento/imunologia , Poli I-C , Gravidez , Ratos WistarRESUMO
Research has shown that inflammatory processes affect brain function and behavior through several neuroimmune pathways. However, high order brain functions affected by inflammation largely remain to be defined. Resting state functional connectivity of synchronized oscillatory activity is a valid approach to understand network processing and high order brain function under different experimental conditions. In the present study multi-electrode EEG recording in awake, freely moving rats was used to study resting state connectivity after administration of lipopolysaccharides (LPS). Male Wistar rats were implanted with 10 cortical surface electrodes and administered with LPS (2 mg/kg) and monitored for symptoms of sickness at 3, 6 and 24 h. Resting state connectivity and power were computed at baseline, 6 and 24 h. Three prominent connectivity bands were identified using a method resistant to spurious correlation: alpha (5-15 Hz), beta-gamma (20-80 Hz), and high frequency oscillation (150-200 Hz). The most prominent connectivity band, alpha, was strongly reduced 6 h after LPS administration, and returned to baseline at 24 h. Beta-gamma connectivity was also reduced at 6 h and remained reduced at 24 h. Interestingly, high frequency oscillation connectivity remained unchanged at 6 h and was impaired 24 h after LPS challenge. Expected elevations in delta and theta power were observed at 6 h after LPS administration, when behavioral symptoms of sickness were maximal. Notably, gamma and high frequency power were reduced 6 h after LPS and returned to baseline by 24 h, when the effects on connectivity were more evident. Finally, increases in cross-frequency coupling elicited by LPS were detected at 6 h for theta-gamma and at 24 h for theta-high frequency oscillations. These studies show that LPS challenge profoundly affects EEG connectivity across all identified bands in a time-dependent manner indicating that inflammatory processes disrupt both bottom-up and top-down communication across the cortex during the peak and resolution of inflammation.
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Encéfalo/efeitos dos fármacos , Eletroencefalografia , Lipopolissacarídeos/toxicidade , Animais , Teorema de Bayes , Encéfalo/fisiologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Citocinas/metabolismo , Eletrodos Implantados , Masculino , Ratos , Ratos WistarRESUMO
Accumulating evidence has shown that lymphocytes modulate behaviour and cognition by direct interactions with the central nervous system. Studies have shown that reconstitution by adoptive transfer of lymphocytes from wild type into immune-deficient mice restores a number of neurobehavioural deficits observed in these models. Moreover, it has been shown that these effects are mostly mediated by T lymphocytes. Studies of adoptive transfer thus far have employed adult mice, but whether lymphocytes may also modulate behaviour during development remains unknown. In this study, neonate lymphocyte-deficient Rag2-/- mice were reconstituted within 48 hours after birth with lymphoid cells from transgenic donors expressing green fluorescent protein, allowing for their identification in various tissues in recipient mice while retaining all functional aspects. Adolescent Rag2-/- and reconstituted Rag2-/- along with C57BL/6J wild-type mice underwent a series of behavioural tests, including open field, social interaction and sucrose preference tests. At 12 weeks, they were evaluated in the Morris water maze (MWM). Reconstituted mice showed changes in almost all aspects of behaviour that were assessed, with a remarkable complete rescue of impaired social behaviour displayed by adolescent Rag2-/- mice. Consistent with previous reports in adult mice, neonatal reconstitution in Rag2-/- mice restored spatial memory in the MWM. The presence of donor lymphocytes in the brain of neonatally reconstituted Rag2-/- mice was confirmed at various developmental points. These findings provide evidence that lymphocytes colonize the brain during post-natal development and modulate behaviour across the lifespan supporting a role for adaptive immunity during brain maturation.
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Transferência Adotiva , Envelhecimento/fisiologia , Animais Recém-Nascidos , Comportamento Exploratório/fisiologia , Síndromes de Imunodeficiência/psicologia , Linfócitos/imunologia , Comportamento Social , Envelhecimento/imunologia , Animais , Animais Recém-Nascidos/imunologia , Animais Recém-Nascidos/fisiologia , Comportamento Animal/fisiologia , Proteínas de Ligação a DNA/genética , Preferências Alimentares/fisiologia , Proteínas de Fluorescência Verde/metabolismo , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/imunologia , Masculino , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Camundongos , Camundongos KnockoutRESUMO
Kynurenic acid, a metabolite of the kynurenine pathway of tryptophan degradation, acts as an endogenous antagonist of alpha7 nicotinic and NMDA receptors and is implicated in a number of neurophysiological and neuropathological processes including cognition and neurodegenerative events. Therefore, kynurenine aminotransferase II (KAT II/AADAT), the enzyme responsible for the formation of the majority of neuroactive kynurenic acid in the brain, has prompted significant interest. Using immunohistochemistry, this enzyme was localized primarily in astrocytes throughout the adult rat brain, but detailed neuroanatomical studies are lacking. Here, we employed quantitative in situ hybridization to analyze the relative expression of KAT II mRNA in the brain of rats under normal conditions and 6â¯h after the administration of lipopolysaccharides (LPSs). Specific hybridization signals for KAT II were detected, with the highest expression in the subventricular zone (SVZ), the rostral migratory stream and the floor of the third ventricle followed by the corpus callosum and the hippocampus. This pattern of mRNA expression was paralleled by differential protein expression, determined by serial dilutions of antibodies (up to 1:1 million), and was confirmed to be primarily astrocytic in nature. The mRNA signal in the SVZ and the hippocampus was substantially increased by the LPS treatment without detectable changes elsewhere. These results demonstrate that KAT II is expressed in the rat brain in a region-specific manner and that gene expression is sensitive to inflammatory processes. This suggests an unrecognized role for kynurenic acid in the brain's germinal zones.
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Astrócitos/enzimologia , Encéfalo/enzimologia , Transaminases/biossíntese , Envelhecimento , Animais , Proteína Duplacortina , Feminino , Masculino , Ratos , Ratos WistarRESUMO
Accumulating evidence supports a role of T cells in behavioral stress responsiveness. Our laboratory previously reported that lymphocyte deficient Rag2(-/-) mice on a BALB/c background display resilience to maladaptive stress responses when compared with immune competent mice in the predator odor exposure (POE) paradigm, while exhibiting similar behavior in a cued fear-conditioning (FC) paradigm. In the present study, Rag2(-/-) mice on a C57BL/6 background were assessed in the same behavioral paradigms, as well as additional tests of anxiety and depressive-like behavior. Furthermore, the effects of naïve CD4(+ ) T cells were evaluated by adoptive transfer of functional cells from nonstressed, wild-type donors to Rag2(-/-) mice. Consistent with our prior results, Rag2(-/-) mice displayed an attenuated startle response after POE. Nevertheless, reconstitution of Rag2(-/-) mice with CD4(+ ) T cells did not modify startle reactivity. Additionally, in contrast with our previous findings, Rag2(-/-) mice showed attenuated fear responses in the FC paradigm compared to wild-type mice and reconstitution with CD4(+ ) T cells promoted fear learning and memory. Notably, reconstitution with CD4(+ ) T cells had anxiolytic and antidepressant-like effects in Rag2(-/-) mice that had not been previously stressed, but had no effect after POE. Taken together, our results support a role of CD4(+ ) T cells in emotionality, but also indicate that they may promote fear responses by enhancing learning and memory processes.
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Ansiedade/fisiopatologia , Linfócitos T CD4-Positivos/fisiologia , Proteínas de Ligação a DNA/genética , Depressão/fisiopatologia , Medo/fisiologia , Memória/fisiologia , Animais , Emoções/fisiologia , Camundongos , Camundongos Knockout , Reflexo de Sobressalto/fisiologiaRESUMO
BACKGROUND: Neuroinflammatory processes are increasingly believed to participate in the pathophysiology of a number of major psychiatric diseases, including depression. Immune activation stimulates the conversion of the amino acid tryptophan to kynurenine, leading to the formation of neuroactive metabolites, such as quinolinic acid and kynurenic acid. These compounds affect glutamatergic neurotransmission, which plays a prominent role in depressive pathology. Increased tryptophan degradation along the kynurenine pathway (KP) has been proposed to contribute to disease etiology. METHODS: We used postmortem brain tissue from the ventrolateral prefrontal cortex (VLPFC) to assess tissue levels of tryptophan and KP metabolites, the expression of several KP enzymes and a series of cytokines as well as tissue pathology, including microglial activation. Tissue samples came from nonpsychiatric controls (n = 36) and individuals with depressive disorder not otherwise specified (DD-NOS, n = 45) who died of natural causes, homicide, accident, or suicide. RESULTS: We found a reduction in the enzymatic conversion of tryptophan to kynurenine, determined using the kynurenine:tryptophan ratio, and reduced messenger RNA expression of the enzymes indoleamine-2,3-dioxygenase 1 and 2 and tryptophan-2,3-dioxygenase in depressed individuals irrespective of the cause of death. These findings correlated with reductions in the expression of several cytokines, including interferon-γ and tumour necrosis factor-α. Notably, quinolinic acid levels were also lower in depressed individuals than controls. LIMITATIONS: Information on the use of antidepressants and other psychotropic medications was insufficient for statistical comparisons. CONCLUSION: Contrary to expectations, the present results indicate that depression, in the absence of medical illness or an overt inflammatory process, is associated with compromised, rather than increased, KP metabolism in the VLPFC.
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Citocinas/metabolismo , Transtorno Depressivo/metabolismo , Cinurenina/metabolismo , Córtex Pré-Frontal/metabolismo , Adulto , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Reação em Cadeia da Polimerase , Córtex Pré-Frontal/patologia , RNA Mensageiro/metabolismoRESUMO
The concept of the brain as an immune privileged organ is rapidly evolving in light of new findings outlining the sophisticated relationship between the central nervous and the immune systems. The role of T cells in brain development and function, as well as modulation of behavior has been demonstrated by an increasing number of studies. Moreover, recent studies have redefined the existence of a brain lymphatic system and the presence of T cells in specific brain structures, such as the meninges and choroid plexus. Nevertheless, much information is needed to further the understanding of brain T cells and their relationship with the central nervous system under non-inflammatory conditions. In the present study we employed the Rag2(-/-) mouse model of lymphocyte deficiency and reconstitution by adoptive transfer to study the temporal and anatomical expansion of T cells in the brain under homeostatic conditions. Lymphopenic Rag2(-/-) mice were reconstituted with 10 million lymphoid cells and studied at one, two and four weeks after transfer. Moreover, lymphoid cells and purified CD4(+) and CD8(+) T cells from transgenic GFP expressing mice were used to define the neuroanatomical localization of transferred cells. T cell numbers were very low in the brain of reconstituted mice up to one week after transfer and significantly increased by 2weeks, reaching wild type values at 4weeks after transfer. CD4(+) T cells were the most abundant lymphocyte subtype found in the brain followed by CD8(+) T cells and lastly B cells. Furthermore, proliferation studies showed that CD4(+) T cells expand more rapidly than CD8(+) T cells. Lymphoid cells localize abundantly in meningeal structures, choroid plexus, and circumventricular organs. Lymphocytes were also found in vascular and perivascular spaces and in the brain parenchyma across several regions of the brain, in particular in structures rich in white matter content. These results provide proof of concept that the brain meningeal system, as well as vascular and perivascular spaces, are homing sites of lymphocytes and suggest the possibility of a brain specific T cell subtype.
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Encéfalo/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Linfopenia/imunologia , Meninges/imunologia , Transferência Adotiva , Animais , Plexo Corióideo/imunologia , Proteínas de Ligação a DNA , Modelos Animais de Doenças , Feminino , Homeostase/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos TransgênicosRESUMO
Inflammatory diseases are highly associated with affective disorders including depression and anxiety. While the role of the innate immune system on emotionality has been extensively studied, the role of adaptive immunity is less understood. Considering that chronic inflammatory conditions are mediated largely by maladaptive lymphocyte function, the role of these cells on brain function and behavior during inflammation warrants investigation. In the present study we employed mice deficient in lymphocyte function and studied behavioral and inflammatory responses during challenge with bacterial lipopolysaccharides (LPS). Rag2(-/-) mice lacking mature lymphocytes were susceptible to death under sub-septic (5 mg/kg) doses of LPS and survived only to moderate (1 mg/kg) doses of LPS. Under these conditions, they displayed attenuated TNF-alpha responses and behavioral symptoms of sickness when compared with immunocompetent mice. Nevertheless, Rag2(-/-) mice had protracted motivational impairments after recovery from sickness suggesting a specific function for lymphocytes on the re-establishment of motivational states after activation of the innate immune system. The behavioral impairments in Rag2(-/-) mice were paralleled by an elevation in plasma corticosterone after behavioral tests. These results provide evidence that the absence of adaptive immunity may be associated with emotional deficits during inflammation and suggest that depressive states associated with medical illness may be mediated in part by impaired lymphocyte responses.
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Proteínas de Ligação a DNA/deficiência , Emoções/efeitos dos fármacos , Comportamento de Doença/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Linfócitos/fisiologia , Análise de Variância , Animais , Temperatura Corporal/efeitos dos fármacos , Corticosterona/sangue , Citocinas/sangue , Citocinas/genética , Proteínas de Ligação a DNA/genética , Comportamento Exploratório/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Microglia/efeitos dos fármacos , Microglia/metabolismo , RNA Mensageiro/metabolismo , Natação/psicologia , Fatores de TempoRESUMO
Significant evidence suggests that exposure to traumatic and/or acute stress in both mice and humans results in compromised immune function that in turn may affect associated brain processes. Additionally, recent studies in mouse models of immune deficiency have suggested that adaptive immunity may play a role during traumatic stress exposure and that impairments in lymphocyte function may contribute to increased susceptibility to various psychogenic stressors. However, rodent studies on the relationship between maladaptive stress responses and lymphocyte deficiency have been complicated by the fact that genetic manipulations in these models may also result in changes in CNS function due to the expression of targeted genes in tissues other than lymphocytes, including the brain. To address these issues we utilized mice with a deletion of recombination-activating gene 2 (Rag2), which has no confirmed expression in the CNS; thus, its loss should result in the absence of mature lymphocytes without altering CNS function directly. Stress responsiveness of immune deficient Rag2(-/-) mice on a BALB/c background was evaluated in three different paradigms: predator odor exposure (POE), fear conditioning (FC) and learned helplessness (LH). These models are often used to study different aspects of stress responsiveness after the exposure to an acute stressor. In addition, immunoblot analysis was used to assess hippocampal BDNF expression under both stressed and non-stressed conditions. Subsequent to POE, Rag2(-/-) mice exhibited a reduced acoustic startle response compared to BALB/c mice; no significant differences in behavior were observed in either FC or LH. Furthermore, analysis of hippocampal BDNF indicated that Rag2(-/-) mice have elevated levels of the mature form of BDNF compared to BALB/c mice. Results from our studies suggest that the absence of mature lymphocytes is associated with increased resilience to stress exposure in the POE and does not affect behavioral responses in the FC and LH paradigms. These findings indicate that lymphocytes play a specific role in stress responsiveness dependent upon the type, nature and intensity of the stressor.
Assuntos
Ansiedade/imunologia , Medo/fisiologia , Estresse Psicológico/imunologia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Condicionamento Psicológico , Proteínas de Ligação a DNA/genética , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Atividade Motora , Reflexo de SobressaltoRESUMO
BACKGROUND: The Stanford Anesthesia Teaching Scholars Program was launched in 2007 to further pedagogic training of faculty and improve residency education. OBJECTIVES: The goals of this article are to describe the program intervention and improvements made based on participant feedback, summarize the characteristics of the faculty enrolled and projects undertaken, and report on program outcomes tracked to date. INTERVENTION: THE TEACHING SCHOLARS PROGRAM HOUSED WITHIN THE DEPARTMENT OF ANESTHESIA SUPPORTS FACULTY IN THESE AREAS: (1) attending education-related meetings; (2) engaging in a monthly seminar on core topics paired with independent study reading; and (3) undertaking a project to improve resident education. Structured interviews with all graduates (n â=â 19; 47% women) were conducted using a pilot-tested questionnaire. RESULTS: A total of 15 of 19 Scholars (79%) were instructors/assistant professors. Sixteen Scholars (84%) attended an off-site education meeting. The Scholars pursued a variety of projects, including curriculum (53%), teaching (26%), administration (11%), assessment (5%), and advising/mentoring (5%). Projects were fully completed by 13 of 19 participants (68%), and 12 of 19 projects (63%) are currently integrated into the residency. Completed projects were published/presented at conferences by 4 of 13 participants (31%), and education grants were received by 3 of 19 participants (16%). CONCLUSIONS: This is the first description of a faculty development (education) program in an anesthesiology department. The program has been well accepted by participants and resulted in increased educational products, some of which have become a permanent part of the residency curriculum. This educational innovation can be replicated in other departments of anesthesiology provided that funding is available for faculty time and meeting expenses.