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1.
CVIR Endovasc ; 7(1): 45, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38733497

RESUMEN

BACKGROUND: Internal hemorrhoids (IH) is a common medical condition that can result in morbidity secondary to bleeding and discomfort. Treatment for IH has traditionally consisted of dietary and conservative medical management, focal treatments including banding and sclerotherapy or hemorrhoidectomy. Recently, rectal artery embolization (RAE) has been studied as a potential treatment for bleeding predominant IH. We performed a common design and data element analysis of studies that report on RAE. MATERIALS AND METHODS: We conducted a qualitative systematic literature review for rectal artery embolization (RAE) for symptomatic hemorrhoidal disease. The screening process involved five online databases (PubMed, Embase, Google Scholar, DOAJ, and Scopus). Additionally, ClinicalTrials.gov was examined for active, unpublished completed studies. The initial search yielded 2000 studies, with 15 studies meeting the inclusion criteria after screening and assessment. The included studies comprised one RCT, one case series, one pilot study and 12 cohort studies. RESULTS: The population analysis revealed a male predominance across all studies, with varying cohort sizes. The baseline Goligher hemorrhoid grade was utilized in 80% of studies. The majority (73.3%) employed a transfemoral approach, and coils were the primary embolic material in 60% of studies, 26.6% were combination of coils and particles, and 6.6% were particles only. Patient selection criteria highlighted RAE's applicability for high surgical risk patients and those with anemia, chronic hematochezia, or treatment-refractory cases. Exclusion criteria emphasized factors such as previous surgeries, colorectal cancer, rectal prolapse, acute hemorrhoidal complications, and contrast allergy. Study designs varied, with cohort studies being the most common (12/15; 80%). Procedural details included the use of metallic coils and detachable micro-coils, with a high technical success rate reported in most studies ranging from 72 to 100%. The follow-up ranged from 1 to 18 months. The majority of studies reported no major immediate or post-procedural complications. CONCLUSION: While all studies focused on RAE as a treatment for IH, there was a great degree of heterogeneity among included studies, particularly regarding inclusion criteria, exclusion criteria, outcomes measures and timeframe. Future literature should attempt to standardize these design elements to help facilitate secondary analyses and increase understanding of RAE as a treatment option.

2.
Mol Psychiatry ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38816586

RESUMEN

The serotonin deficit hypothesis explanation for major depressive disorder (MDD) has persisted among clinicians and the general public alike despite insufficient supporting evidence. To combat rising mental health crises and eroding public trust in science and medicine, researchers and clinicians must be able to communicate to patients and the public an updated framework of MDD: one that is (1) accessible to a general audience, (2) accurately integrates current evidence about the efficacy of conventional serotonergic antidepressants with broader and deeper understandings of pathophysiology and treatment, and (3) capable of accommodating new evidence. In this article, we summarize a framework for the pathophysiology and treatment of MDD that is informed by clinical and preclinical research in psychiatry and neuroscience. First, we discuss how MDD can be understood as inflexibility in cognitive and emotional brain circuits that involves a persistent negativity bias. Second, we discuss how effective treatments for MDD enhance mechanisms of neuroplasticity-including via serotonergic interventions-to restore synaptic, network, and behavioral function in ways that facilitate adaptive cognitive and emotional processing. These treatments include typical monoaminergic antidepressants, novel antidepressants like ketamine and psychedelics, and psychotherapy and neuromodulation techniques. At the end of the article, we discuss this framework from the perspective of effective science communication and provide useful language and metaphors for researchers, clinicians, and other professionals discussing MDD with a general or patient audience.

3.
Materials (Basel) ; 17(3)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38591418

RESUMEN

Cylindrical Inconel 718 specimens were fabricated via a blown-powder, laser-directed energy deposition (DED-L) additive manufacturing (AM) process equipped with a dual thermal monitoring system to learn key process-structure relationships. Thermographic inspection of the heat affected zone (HAZ) and melt pool was performed with different layer-to-layer time intervals of ~0 s, 5 s, and 10 s, using an infrared camera and dual-wavelength pyrometer, respectively. Maximum melt pool temperatures were found to increase with layer number within a substrate affected zone (SAZ), and then asymptotically decrease. As the layer-to-layer time interval increased the HAZ temperature responses became more repetitive, indicating a desirable approach for achieving a more homogeneous microstructure along the height of a part. Microstructural variations in grain size and the coexistence of specific precipitate phases and Laves phases persisted among the investigated samples despite the employed standard heat treatment. This indicates that the effectiveness of any post DED-L heat treatment depends significantly on the initial, as-printed microstructure. Overall, this study demonstrates the importance of part size, part number per build, and time intervals on DED-L process parameter selection and post-process heat treatments for achieving better quality control.

4.
Curr Oncol Rep ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647995

RESUMEN

PURPOSE OF REVIEW: To provide an update on the current state of percutaneous thermal ablation in the treatment of sarcoma. RECENT FINDINGS: Data continue to accrue in support of ablation for local control and palliation of specific sarcoma subtypes such as extra-abdominal desmoid fibromatosis and for broader indications such as the treatment of oligometastatic disease. The synergistic possibilities of various combination therapies such as cryoablation and immunotherapy represent intriguing areas of active investigation. Histotripsy is an emerging non-invasive, non-thermal ablative modality that may further expand the therapeutic arsenal for sarcoma treatment. Percutaneous thermal ablation is a valuable tool in the multidisciplinary management of sarcoma, offering a minimally invasive adjunct to surgery and radiation therapy. Although there remains a paucity of high-level evidence specific to sarcomas, ablation techniques are demonstrably safe and effective for achieving local tumor control and providing pain relief in select patients and are of particular benefit in those with metastatic disease or requiring palliative care.

5.
Radiographics ; 44(2): e230075, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38271257

RESUMEN

Lymphatic flow and anatomy can be challenging to study, owing to variable lymphatic anatomy in patients with diverse primary or secondary lymphatic pathologic conditions and the fact that lymphatic imaging is rarely performed in healthy individuals. The primary components of the lymphatic system outside the head and neck are the peripheral, retroperitoneal, mesenteric, hepatic, and pulmonary lymphatic systems and the thoracic duct. Multiple techniques have been developed for imaging components of the lymphatic system over the past century, with trade-offs in spatial, temporal, and contrast resolution; invasiveness; exposure to ionizing radiation; and the ability to obtain information on dynamic lymphatic flow. More recently, dynamic contrast-enhanced (DCE) MR lymphangiography (MRL) has emerged as a valuable tool for imaging both lymphatic flow and anatomy in a variety of congenital and acquired primary or secondary lymphatic disorders. The authors provide a brief overview of lymphatic physiology, anatomy, and imaging techniques. Next, an overview of DCE MRL and the development of an MRL practice and workflow in a hybrid interventional MRI suite incorporating cart-based in-room US is provided, with an emphasis on multidisciplinary collaboration. The spectrum of congenital and acquired lymphatic disorders encountered early in an MRL practice is provided, with emphasis on the diversity of imaging findings and how DCE MRL can aid in diagnosis and treatment of these patients. Methods such as DCE MRL for assessing the hepatic and mesenteric lymphatic systems and emerging technologies that may further expand DCE MRL use such as three-dimensional printing are introduced. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.


Asunto(s)
Enfermedades Linfáticas , Linfografía , Humanos , Linfografía/métodos , Medios de Contraste , Imagen por Resonancia Magnética/métodos , Enfermedades Linfáticas/diagnóstico por imagen , Enfermedades Linfáticas/patología , Sistema Linfático/patología
6.
J Neurophysiol ; 131(1): 64-74, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38050689

RESUMEN

(2R,6R)-Hydroxynorketamine (HNK) is a ketamine metabolite that shows rapid antidepressant-like effects in preclinical studies and lacks the adverse N-methyl-d-aspartate receptor (NMDAR) inhibition-related properties of ketamine. Investigating how (2R,6R)-HNK exerts its antidepressant actions may be informative in the design of novel pharmacotherapies with improved safety and efficacy. We sought to identify the molecular substrates through which (2R,6R)-HNK induces functional changes at excitatory synapses, a prevailing hypothesis for how rapid antidepressant effects are initiated. We recorded excitatory postsynaptic potentials in hippocampal slices from male Wistar Kyoto rats, which have impaired hippocampal plasticity and are resistant to traditional antidepressants. (2R,6R)-HNK (10 µM) led to a rapid potentiation of electrically evoked excitatory postsynaptic potentials at Schaffer collateral CA1 stratum radiatum synapses. This potentiation was associated with a decrease in paired pulse facilitation, suggesting an increase in the probability of glutamate release. The (2R,6R)-HNK-induced potentiation was blocked by inhibiting either cyclic adenosine monophosphate (cAMP) or its downstream target, cAMP-dependent protein kinase (PKA). As cAMP is a potent regulator of brain-derived neurotrophic factor (BDNF) release, we assessed whether (2R,6R)-HNK exerts this acute potentiation through a rapid increase in cAMP-dependent BDNF-TrkB signaling. We found that the cAMP-PKA-dependent potentiation was not dependent on TrkB activation by BDNF, which functionally delimits the acute synaptic effects of (2R,6R)-HNK from its sustained BDNF-dependent actions in vivo. These results suggest that, by potentiating glutamate release via cAMP-PKA signaling, (2R,6R)-HNK initiates acute adaptations in fast excitatory synaptic transmission that promote structural plasticity leading to maintained antidepressant action.NEW & NOTEWORTHY Ketamine is a rapid-acting antidepressant and its preclinical effects are mimicked by its (2R,6R)-(HNK) metabolite. We found that (2R,6R)-HNK initiates acute adaptations in fast excitatory synaptic transmission by potentiating glutamate release via cAMP-PKA signaling at hippocampal Schaffer collateral synapses. This cAMP-PKA-dependent potentiation was not dependent on TrkB activation by BDNF, which functionally delimits the rapid synaptic effects of (2R,6R)-HNK from its sustained BDNF-dependent actions that are thought to maintain antidepressant action in vivo.


Asunto(s)
Ketamina , Ratas , Animales , Masculino , Ketamina/farmacología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Antidepresivos/metabolismo , Antidepresivos/farmacología , Hipocampo/metabolismo , Ácido Glutámico/metabolismo
7.
Neuropsychopharmacology ; 49(2): 443-454, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37833589

RESUMEN

Trauma and chronic stress exposure are the strongest predictors of lifetime neuropsychiatric disease presentation. These disorders often have significant sex biases, with females having higher incidences of affective disorders such as major depression, anxiety, and PTSD. Understanding the mechanisms by which stress exposure heightens disease vulnerability is essential for developing novel interventions. Current rodent stress models consist of a battery of sensory, homeostatic, and psychological stressors that are ultimately integrated by corticotropin-releasing factor (CRF) neurons to trigger corticosteroid release. These stress paradigms, however, often differ between research groups in the type, timing, and duration of stressors utilized. These inconsistencies, along with the variability of individual animals' perception and response to each stressor, present challenges for reproducibility and translational relevance. Here, we hypothesized that a more direct approach using chemogenetic activation of CRF neurons would recapitulate the effects of traditional stress paradigms and provide a high-throughput method for examining stress-relevant phenotypes. Using a transgenic approach to express the Gq-coupled Designer Receptor Exclusively Activated by Designer Drugs (DREADD) receptor hM3Dq in CRF-neurons, we found that the DREADD ligand clozapine-N-oxide (CNO) produced an acute and robust activation of the hypothalamic-pituitary-adrenal (HPA) axis, as predicted. Interestingly, chronic treatment with this method of direct CRF activation uncovered a novel sex-specific dissociation of glucocorticoid levels with stress-related outcomes. Despite hM3Dq-expressing females producing greater corticosterone levels in response to CNO than males, hM3Dq-expressing males showed significant typical physiological stress sensitivity with reductions in body and thymus weights. hM3Dq-expressing females while resistant to the physiological effects of chronic CRF activation, showed significant increases in baseline and fear-conditioned freezing behaviors. These data establish a novel mouse model for interrogating stress-relevant phenotypes and highlight sex-specific stress circuitry distinct for physiological and limbic control that may underlie disease risk.


Asunto(s)
Hormona Liberadora de Corticotropina , Neuronas , Ratones , Masculino , Animales , Femenino , Hormona Liberadora de Corticotropina/farmacología , Reproducibilidad de los Resultados , Ansiedad , Miedo
8.
Acad Radiol ; 31(3): 977-993, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37722951

RESUMEN

RATIONALE AND OBJECTIVES: Genicular artery embolization (GAE) is an emerging, potentially effective treatment option in patients with knee osteoarthritis (OA). This study aimed to describe the current state of common design data elements (CDDEs) and core outcome measures (COMs) in recent trials of GAE for knee OA. MATERIALS AND METHODS: A comprehensive search of seven online databases were searched within the Nested Knowledge AutoLit living review platform, followed by categorization of primary and secondary outcomes. Studies were tagged with the relevant outcomes of interest in each article. Results were synthesized and examined for the CDDEs. RESULTS: Pain is the most frequent reported outcome, present in 23 of the 24 studies (95.8%). However, there is considerable variability in the description of in the study designs, procedural techniques, embolic materials, time points, and MRI parameters. Greater consistency is observed in eligibility criteria, and adverse events reporting. Although findings thus far have been favorable, current data is still constrained by the heterogeneity of the study design, embolization area nomenclature, limited follow-up, and in many cases, the absence of control group. CONCLUSION: To enhance the potential for future meta-analyses and robust, evidence-based evaluations of GAE as a treatment for knee OA, further research is required to address the identified shortcomings. By establishing more standardized protocols, the efficacy and safety of GAE can be more accurately assessed and understood.


Asunto(s)
Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/terapia , Osteoartritis de la Rodilla/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud , Resultado del Tratamiento , Imagen por Resonancia Magnética , Arterias
9.
Neuropsychopharmacology ; 49(1): 83-95, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37709943

RESUMEN

The predominant inhibitory neurotransmitter in the brain, γ-aminobutyric acid (GABA), acts at ionotropic GABAA receptors to counterbalance excitation and regulate neuronal firing. GABAA receptors are heteropentameric channels comprised from subunits derived from 19 different genes. GABAA receptors have one of the richest and well-developed pharmacologies of any therapeutic drug target, including agonists, antagonists, and positive and negative allosteric modulators (PAMs, NAMs). Currently used PAMs include benzodiazepine sedatives and anxiolytics, barbiturates, endogenous and synthetic neurosteroids, and general anesthetics. In this article, I will review evidence that these drugs act at several distinct binding sites and how they can be used to alter the balance between excitation and inhibition. I will also summarize existing literature regarding (1) evidence that changes in GABAergic inhibition play a causative role in major depression, anxiety, postpartum depression, premenstrual dysphoric disorder, and schizophrenia and (2) whether and how GABAergic drugs exert beneficial effects in these conditions, focusing on human studies where possible. Where these classical therapeutics have failed to exert benefits, I will describe recent advances in clinical and preclinical drug development. I will also highlight opportunities to advance a generation of GABAergic therapeutics, such as development of subunit-selective PAMs and NAMs, that are engendering hope for novel tools to treat these devastating conditions.


Asunto(s)
Ansiolíticos , Receptores de GABA-A , Humanos , Receptores de GABA-A/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Sitios de Unión , Encéfalo/metabolismo
10.
eNeuro ; 10(9)2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37699705

RESUMEN

The sucrose preference test (SPT) is a widely used preclinical assay for studying stress-sensitive reward behaviors and antidepressant treatments in rodents, with some face, construct, and predictive validity. However, while stress-induced loss of sucrose preference is presumed to reflect an anhedonic-like state, little detail is known about what behavioral components may influence performance in the SPT in stress-naive or stressed rodents. We analyzed the licking microstructure of mice during the SPT to evaluate how preference is expressed and lost following chronic stress. In stress-naive mice, preference is expressed as both longer and more numerous drinking bouts at the sucrose bottle, compared with the water bottle. We also found evidence that memory of the sucrose bottle location supports preference. Through manipulations of the caloric content of the sweetener or caloric need of the mouse, we found that energy demands and satiety signals do not affect either preference or the underlying drinking behavior. Both acute and chronic stress impaired sucrose location memory and reduced the number of drinking bouts at the sucrose bottle, the latter of which explained the loss of sucrose preference in stress susceptible mice compared with stress resilient mice. Female mice generally exhibited similar drinking behavior to male mice but may be less susceptible to chronic stress and display better memory performance than male mice, both before and after chronic stress. Our data suggest that chronic stress inhibits a sucrose preference by reducing reward seeking behavior without affecting palatability.


Asunto(s)
Sacarosa , Edulcorantes , Ratones , Masculino , Femenino , Animales , Conducta Animal , Conducta de Ingestión de Líquido
11.
AJOG Glob Rep ; 3(4): 100257, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37701754

RESUMEN

INTRODUCTION: Vaginal stenosis is a common complication following construction of a neovagina with vascularized myocutaneous flaps. This is primarily because of inconsistent or inappropriate vaginal dilator use. Image-guided recanalization, especially for obstructed genitourinary tracts, is an emerging idea in interventional radiology. Although multiple surgical techniques have been reported to treat vaginal agenesis or obstruction, the idea of image-guided recanalization of vaginal stenosis is a relatively new management strategy for vaginal stenosis. CASE: We present a challenging case of a patient who initially presented with the complaint of increasing pelvic pressure after the creation of a neovagina via vaginoplasty. She had a distal neovagina created after extensive surgical resection for a large infiltrating pelvic rectal adenocarcinoma. A computed tomography scan revealed a fluid-filled neovaginal abscess. Examination under anesthesia revealed complete stenosis of the neovagina with no identifiable tract for dilation. INTERVENTION: A computed tomography scan and fluoroscopy-guided sharp recanalization of the stenosed neovagina was performed, followed by serial fluoroscopic balloon angioplasty to dilate the stenosed neovagina. Finally, the patient underwent a gynecologic surgery for the excision of remaining granulation tissue to produce a more permanent patent neovagina, followed by regular and proper use of vaginal dilators to ensure patency. CONCLUSION: This case report demonstrates that image-guided techniques can be used to aid in vaginal recanalization in the postoperative setting.

12.
Behav Brain Res ; 452: 114554, 2023 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-37356670

RESUMEN

Major depressive disorder (MDD) is a debilitating and costly human condition. Treatment for MDD relies heavily on the use of antidepressants that are slow to produce mood-related changes and are not effective in all patients, such as selective serotonin reuptake inhibitors (SSRIs). Several novel compounds, including negative allosteric modulators of GABA-A receptors containing the α5-subunit (GABA-NAMs), are under investigation for potential fast acting therapeutic use in MDD. Preclinical evidence that these compounds produce a rapid antidepressant-like response comes primarily from simple tests of escape behavior and preference for rewarding stimuli after chronic stress. To increase the ethological relevance of these compounds, we tested the hypothesis that the GABA-NAM, L-655,708, would produce an antidepressant-like response in more complex stress-sensitive social and sex behaviors, which are of relevance to the symptoms of human depression. In male rats subjected to chronic restraint stress, injection of L-655,708 increased reward in a sexual conditioned place preference task, increased male sexual activity with a receptive female, and re-established male social dominance hierarchies within 24 h. We also report increased sucrose preference in the social defeat stress (SDS) model of depression following GABA-NAM administration, demonstrating that its antidepressant-like actions are independent of the type of chronic stress administered. This work extends the impact of GABA-NAMs beyond traditional tests of anhedonia and further supports the development of alpha5 subunit-selective GABA-NAMs as a potential fast-acting therapeutic approach for treating human MDD.


Asunto(s)
Trastorno Depresivo Mayor , Receptores de GABA , Ratas , Humanos , Masculino , Femenino , Animales , Trastorno Depresivo Mayor/tratamiento farmacológico , Antidepresivos/farmacología , Receptores de GABA-A/fisiología , Conducta Sexual , Ácido gamma-Aminobutírico
13.
Neuropharmacology ; 231: 109504, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36921889

RESUMEN

Psychedelic compounds have shown extraordinary potential in treating a wide range of neuropsychiatric disorders. Psilocybin, for example, has now been shown in several clinical trials to induce a rapid (within days) and persistent (3-12 months) improvement in human treatment-resistant depression and other neuropsychiatric conditions. Here we review the preclinical models and experimental approaches that have been used to study the neurobiological actions of psychedelic drugs. We further summarize the insights these studies have provided into the possible mechanisms underlying the induction of their therapeutic actions, including the receptors to which psychedelics bind and the second messenger signaling cascades that they activate. We also discuss potential biological processes that psychedelics may alter to produce the lasting amelioration of symptoms, including improvements in synaptic structure and function and suppression of inflammation. Improved mechanistic understanding of psychedelic drug actions will aid in the advancement of these promising new medicines. This article is part of the Special Issue on "National Institutes of Health Psilocybin Research Speaker Series".


Asunto(s)
Trastorno Depresivo Resistente al Tratamiento , Alucinógenos , Estados Unidos , Humanos , Psilocibina/farmacología , Psilocibina/uso terapéutico , Alucinógenos/farmacología , Alucinógenos/uso terapéutico , Trastorno Depresivo Resistente al Tratamiento/tratamiento farmacológico , Inflamación/tratamiento farmacológico
14.
Clin Nucl Med ; 48(4): e209-e211, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36728209

RESUMEN

ABSTRACT: PET/CT plays a crucial role in the management of prostate cancer with several emerging and established radiopharmaceuticals, including 18 F-piflufolastat and 11 C-choline. These radiotracers are thought to be relatively specific to prostate cancer; however, uptake has also been demonstrated in other benign and malignant lesions. Nodular fasciitis is a rapidly growing benign soft tissue neoplasm that is typically self-limiting. Although a few case reports describe 68 Ga-PSMA uptake in nodular fasciitis, uptake of 11 C-choline and other PSMA-targeted PET probes, including 18 F-piflufolastat, have not previously been reported. We present a novel case of nodular fasciitis demonstrating both 18 F-piflufolastat and 11 C-choline avidity.


Asunto(s)
Fascitis , Fibroma , Neoplasias de la Próstata , Humanos , Masculino , Radioisótopos de Carbono , Colina , Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata/patología , Radiofármacos , Radioisótopos de Flúor
15.
J Neurosci ; 43(6): 1038-1050, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36596696

RESUMEN

Ketamine is a well-characterized NMDA receptor (NMDAR) antagonist, although the relevance of this pharmacology to its rapid (within hours of administration) antidepressant actions, which depend on mechanisms convergent with strengthening of excitatory synapses, is unclear. Activation of synaptic NMDARs is necessary for the induction of canonical long-term potentiation (LTP) leading to a sustained expression of increased synaptic strength. We tested the hypothesis that induction of rapid antidepressant effects requires NMDAR activation, by using behavioral pharmacology, western blot quantification of hippocampal synaptoneurosomal protein levels, and ex vivo hippocampal slice electrophysiology in male mice. We found that ketamine exerts an inverted U-shaped dose-response in antidepressant-sensitive behavioral tests, suggesting that an excessive NMDAR inhibition can prevent ketamine's antidepressant effects. Ketamine's actions to induce antidepressant-like behavioral effects, up-regulation of hippocampal AMPAR subunits GluA1 and GluA2, as well as metaplasticity measured ex vivo using electrically-stimulated LTP, were abolished by pretreatment with other non-antidepressant NMDAR antagonists, including MK-801 and CPP. Similarly, the antidepressant-like actions of other putative rapid-acting antidepressant drugs (2R,6R)-hydroxynorketamine (ketamine metabolite), MRK-016 (GABAAα5 negative allosteric modulator), and LY341495 (mGlu2/3 receptor antagonist) were blocked by NMDAR inhibition. Ketamine acted synergistically with an NMDAR positive allosteric modulator to exert antidepressant-like behavioral effects and activation of the NMDAR subunit GluN2A was necessary and sufficient for such relevant effects. We conclude rapid-acting antidepressant compounds share a common downstream NMDAR-activation dependent effector mechanism, despite variation in initial pharmacological targets. Promoting NMDAR signaling or other approaches that enhance NMDAR-dependent LTP-like synaptic potentiation may be an effective antidepressant strategy.SIGNIFICANCE STATEMENT The anesthetic and antidepressant drug ketamine is well-characterized as an NMDA receptor (NMDAR) antagonist; though, the relevance and full impact of this pharmacology to its antidepressant actions is unclear. We found that NMDAR activation, which occurs downstream of their initial actions, is necessary for the beneficial effects of ketamine and several other putative antidepressant compounds. As such, promoting NMDAR signaling, or other approaches that enhance NMDAR-dependent long-term potentiation (LTP)-like synaptic potentiation in vivo may be an effective antidepressant strategy directly, or acting synergistically with other drug or interventional treatments.


Asunto(s)
Ketamina , Masculino , Ratones , Animales , Ketamina/farmacología , N-Metilaspartato , Receptores de N-Metil-D-Aspartato/metabolismo , Depresión/tratamiento farmacológico , Antidepresivos/farmacología
16.
Neuropsychopharmacology ; 48(1): 90-103, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36057649

RESUMEN

What changes in brain function cause the debilitating symptoms of depression? Can we use the answers to this question to invent more effective, faster acting antidepressant drug therapies? This review provides an overview and update of the converging human and preclinical evidence supporting the hypothesis that changes in the function of excitatory synapses impair the function of the circuits they are embedded in to give rise to the pathological changes in mood, hedonic state, and thought processes that characterize depression. The review also highlights complementary human and preclinical findings that classical and novel antidepressant drugs relieve the symptoms of depression by restoring the functions of these same synapses and circuits. These findings offer a useful path forward for designing better antidepressant compounds.


Asunto(s)
Depresión , Sinapsis , Humanos , Depresión/tratamiento farmacológico , Antidepresivos/uso terapéutico , Antidepresivos/farmacología , Recompensa , Plasticidad Neuronal
17.
Biol Psychiatry ; 93(6): 489-501, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36435669

RESUMEN

BACKGROUND: Opioid discontinuation generates a withdrawal syndrome marked by increased negative affect. Increased symptoms of anxiety and dysphoria during opioid discontinuation are significant barriers to achieving long-term abstinence in opioid-dependent individuals. While adaptations in the nucleus accumbens are implicated in opioid abstinence syndrome, the precise neural mechanisms are poorly understood. Additionally, our current knowledge is limited to changes following natural and semisynthetic opioids, despite recent increases in synthetic opioid use and overdose. METHODS: We used a combination of cell subtype-specific viral labeling and electrophysiology in male and female mice to investigate structural and functional plasticity in nucleus accumbens medium spiny neuron (MSN) subtypes after fentanyl abstinence. We characterized molecular adaptations after fentanyl abstinence with subtype-specific RNA sequencing and weighted gene co-expression network analysis. We used viral-mediated gene transfer to manipulate the molecular signature of fentanyl abstinence in D1-MSNs. RESULTS: Here, we show that fentanyl abstinence increases anxiety-like behavior, decreases social interaction, and engenders MSN subtype-specific plasticity in both sexes. D1-MSNs, but not D2-MSNs, exhibit dendritic atrophy and an increase in excitatory drive. We identified a cluster of coexpressed dendritic morphology genes downregulated selectively in D1-MSNs that are transcriptionally coregulated by E2F1. E2f1 expression in D1-MSNs protects against loss of dendritic complexity, altered physiology, and negative affect-like behaviors caused by fentanyl abstinence. CONCLUSIONS: Our findings indicate that fentanyl abstinence causes unique structural, functional, and molecular changes in nucleus accumbens D1-MSNs that can be targeted to alleviate negative affective symptoms during abstinence.


Asunto(s)
Analgésicos Opioides , Fentanilo , Ratones , Masculino , Femenino , Animales , Fentanilo/metabolismo , Núcleo Accumbens/fisiología , Neuronas/metabolismo , Ratones Endogámicos C57BL , Receptores de Dopamina D1/metabolismo , Ratones Transgénicos
18.
Clin Endocrinol (Oxf) ; 98(2): 177-189, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36263687

RESUMEN

OBJECTIVE: The objective of this study was to evaluate the role of adrenal venous sampling (AVS) in guiding the management of patients with corticotropin (ACTH)-independent glucocorticoid secretory autonomy and bilateral adrenal masses. DESIGN AND PATIENTS: A cohort with 25 patients underwent AVS and surgical management. MEASUREMENTS: Cortisol was measured from the adrenal veins (AVs) and inferior vena cava (IVC). AV/IVC cortisol ratio and cortisol lateralization ratio (CLR) (dominant AV cortisol concentration divided by the nondominant AV cortisol concentration) were calculated. Posthoc receiver-operating characteristic curves were generated to determine the specificity of revised AV/IVC cortisol ratio and CLR in differentiating unilateral from bilateral disease. RESULTS: Patients underwent unilateral (n = 21) or bilateral (n = 4) adrenalectomy. The mean AV/IVC cortisol ratio for unilateral adrenalectomy was 12.1 ± 9.6 (dominant) and 4.7 ± 3.8 (contralateral) with a mean CLR of 3.6 ± 3.5. The mean AV/IVC cortisol ratio for bilateral adrenalectomy was 7.5 ± 2.1, with a mean CLR of 1.1 ± 0.6. At a mean follow-up of 22 months, one patient who underwent unilateral adrenalectomy for the predicted bilateral disease developed recurrent mild autonomous cortisol secretion. Posthoc analyses demonstrated a specificity of 95%-100% for unilateral disease with AV/IVC cortisol ratio >9 for one side, <2.0 for the opposite side and a CLR > 2.3. The specificity was 80%-90% for bilateral disease with AV/IVC cortisol ratio >5.1 bilaterally and a CLR < 1.1. CONCLUSIONS: Among patients with bilateral adrenal masses and ACTH-independent autonomous cortisol secretion, AVS can distinguish between unilateral and bilateral disease with high specificity and may guide surgical management.


Asunto(s)
Enfermedades de las Glándulas Suprarrenales , Hiperaldosteronismo , Humanos , Hidrocortisona , Glándulas Suprarrenales/irrigación sanguínea , Adrenalectomía , Hormona Adrenocorticotrópica , Hiperaldosteronismo/cirugía , Estudios Retrospectivos , Aldosterona
19.
J Vasc Interv Radiol ; 34(1): 46-53.e4, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36202337

RESUMEN

PURPOSE: To investigate the effect of simultaneous use of dual applicators on the image quality of real-time magnetic resonance (MR) thermometry and to characterize the dual-applicator treatment zone pattern during MR imaging-guided microwave ablation (MWA). MATERIALS AND METHODS: MWA experiments were performed on a 1.5-T MR scanner with 2 commercial microwave systems (902-928 MHz). Phantom experiments were first performed to evaluate the effect of dual-applicator MWA on the image quality of MR. Then, porcine tissue model experiments were conducted with real-time MR thermometry using either a single applicator or dual applicators inserted 2.6, 3.6, and 4.6 cm apart. Fiberoptic thermal probes were used to measure the temperature changes at the tissue surface. RESULTS: Simultaneous use of dual applicators resulted in a decrease in the relative signal-to-noise ratio (SNR) in the MR thermometry images to 55% ± 2.9% when compared with that of a single applicator (86.2% ± 2.0%). Despite the lower SNR, the temperature and ablation zone maps were of adequate quality to allow visualization of the ablation zone(s). The extents of increase in the temperature at the tissue surface using dual applicators (19.7 °C ± 2.6 °C) and a single applicator (18.2 °C ± 3.3 °C) were not significantly different (P = .40). Treatment zones were significantly larger (P < .05) in dual-applicator ablations (29.4 ± 0.4, 39.9 ± 0.6, and 42.6 ± 0.9 cm2 with 2.6-, 3.6-, and 4.6-cm spacing, respectively) at the end of the ablation procedure than in the single-applicator MWA (18.6 ± 0.9 cm2). CONCLUSIONS: MR imaging-guided dual-applicator MWA produced larger ablation zones while allowing adequate real-time MR thermometry image quality for monitoring the evolution of the treatment zone.


Asunto(s)
Microondas , Termometría , Porcinos , Animales , Microondas/uso terapéutico , Hígado/patología , Termometría/métodos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética
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