RESUMEN
Thyroglobulin (Tg) is an important tool to evaluate the persistence and recurrence risk in differentiated thyroid cancer (DTC). We aimed to evaluate the correlation between pre-radioiodine therapy stimulated Tg (pre-RAI Tg) levels and the first response to treatment evaluation, and to establish a cut-off pre-RAI Tg threshold for predicting an initial excellent response. Retrospective cohort study of DTC patients who underwent total thyroidectomy and radioiodine therapy. Response to therapy was evaluated 6 to 24 months after initial therapy, and patients were classified as: excellent response (ER); indeterminate response (IndR) and incomplete response (IncR). Total patients: 166 among which 85.5% female with mean age of 47.6 ± 13 years. The ER had a significantly lower pre-RAI Tg in comparison to IndR (p<0.001) and IncR (p<0.001), and pre-RAI Tg were different between the IndR and IncR (p=0.02). A cut-off pre-RAI Tg value at 7.55ng/ml was obtained by receiver operating characteristics curve for differentiating ER from IndR and IncR. The area under curve was 0.832 (95% CI 0.76-0.91). In multivariate analysis, ATA low-risk (RR 1.61, 95% CI 1.06-2.43, p=0.025) and Tg below 7.55ng/ml (RR 2.17, 95% CI 1.52-3.10, p<0.001) were associated with ER. After a median of 7.4-year follow-up, 124 (74.7%) patients were allocated into ER, 22 (13.2%) into IndR, and 20 (12%) into IncR. In conclusion, pre-RAI Tg predicts first evaluation of treatment response. Pre-RAI Tg cut-off was a key predictor of initial excellent response to therapy and may be an important tool in the follow-up of DTC patients.
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Radioisótopos de Yodo , Tiroglobulina , Neoplasias de la Tiroides , Humanos , Femenino , Neoplasias de la Tiroides/radioterapia , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/terapia , Persona de Mediana Edad , Masculino , Radioisótopos de Yodo/uso terapéutico , Tiroglobulina/sangre , Estudios Retrospectivos , Resultado del Tratamiento , Adulto , Pronóstico , Curva ROC , TiroidectomíaRESUMEN
Oligodendrocyte precursor cells (OPCs) are uniformly distributed in the mammalian brain; however, their function is rather heterogeneous in respect to their origin, location, receptor/channel expression and age. The basic helix-loop-helix transcription factor Olig2 is expressed in all OPCs as a pivotal determinant of their differentiation. Here, we identified a subset (2%-26%) of OPCs lacking Olig2 in various brain regions including cortex, corpus callosum, CA1 and dentate gyrus. These Olig2 negative (Olig2neg ) OPCs were enriched in the juvenile brain and decreased subsequently with age, being rarely detectable in the adult brain. However, the loss of this population was not due to apoptosis or microglia-dependent phagocytosis. Unlike Olig2pos OPCs, these subset cells were rarely labeled for the mitotic marker Ki67. And, accordingly, BrdU was incorporated only by a three-day long-term labeling but not by a 2-hour short pulse, suggesting these cells do not proliferate any more but were derived from proliferating OPCs. The Olig2neg OPCs exhibited a less complex morphology than Olig2pos ones. Olig2neg OPCs preferentially remain in a precursor stage rather than differentiating into highly branched oligodendrocytes. Changing the adjacent brain environment, for example, by acute injuries or by complex motor learning tasks, stimulated the transition of Olig2pos OPCs to Olig2neg cells in the adult. Taken together, our results demonstrate that OPCs transiently suppress Olig2 upon changes of the brain activity.
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Lesiones Encefálicas , Células Precursoras de Oligodendrocitos , Animales , Células Precursoras de Oligodendrocitos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Factor de Transcripción 2 de los Oligodendrocitos/metabolismo , Oligodendroglía/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular , Lesiones Encefálicas/metabolismo , Mamíferos/metabolismoRESUMEN
OBJECTIVE: Prospective data on the accuracy of ultrasound (US) classification systems in thyroid nodules are still scarce. The aim of this study is to compare the accuracy of the American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TIRADS) and European (EU)-TIRADS classification systems. DESIGN AND PATIENTS: Consecutive patients with one or more thyroid nodule(s) who underwent fine-needle aspiration (FNA) under ultrasonographic guidance (FNA-US) were prospectively evaluated. MEASUREMENTS: Clinical evaluation and US data were collected. The reference standard used for this study was FNA-US cytology and histopathological diagnosis. RESULTS: A total of 186 thyroid nodules in 166 patients were evaluated, resulting in 168 nodules from 149 patients with conclusive benign or malignant results. Sensitivity, specificity, negative predictive value (NPV) and false negative (FN) were 100.0%, 28.7%, 100.0% and 0.0%, respectively, for ACR-TIRADS; and 90.0%, 19.1%, 96.8% and 9.1% (n = 1), respectively, for EU-TIRADS. The number of unnecessary FNA-US indicated by ACR-TIRADS was lower than EU-TIRADS (71.3% vs. 80.9%, p = .017), and the number of possibly avoided FNA-US was higher (26.7% vs. 17.8%). Using the same threshold of ACR-TIRADS to indicate FNA-US in EU-TIRADS 3 nodules (2.5 cm), there was an improvement in specificity (30.6%) and avoided FNA-US (28.6%). The best performance of both systems was demonstrated when FNA-US would be indicated only in highly suspicious nodules and/or in the presence of lymphadenopathy, with 85.7% and 89.3% of possibly avoided FNA-US for ACR-TIRADS and EU-TIRADS, respectively, without increasing FN. CONCLUSION: Both systems presented high sensitivity, but low specificity in selecting nodules for FNA-US. The use of nodular size for FNA-US selection is questioned.
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Neoplasias de la Tiroides , Nódulo Tiroideo , Humanos , Nódulo Tiroideo/patología , Neoplasias de la Tiroides/patología , Biopsia con Aguja Fina/métodos , Estudios Retrospectivos , Ultrasonografía/métodosRESUMEN
We documented the contributions of Field Epidemiology Training Program (FETP) trainees and graduates to global COVID-19 preparedness and response efforts. During February-July 2021, we conducted surveys designed in accordance with the World Health Organization's COVID-19 Strategic Preparedness and Response Plan. We quantified trainee and graduate engagement in responses and identified themes through qualitative analysis of activity descriptions. Thirty-two programs with 2,300 trainees and 7,372 graduates reported near-universal engagement across response activities, particularly those aligned with the FETP curriculum. Graduates were more frequently engaged than were trainees in pandemic response activities. Common themes in the activity descriptions were epidemiology and surveillance, leading risk communication, monitoring and assessment, managing logistics and operations, training and capacity building, and developing guidelines and protocols. We describe continued FETP contributions to the response. Findings indicate the wide-ranging utility of FETPs to strengthen countries' emergency response capacity, furthering global health security.
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COVID-19 , Salud Pública , Humanos , Salud Pública/métodos , Brotes de Enfermedades , COVID-19/epidemiología , COVID-19/prevención & control , Vigilancia de la Población/métodos , Salud GlobalRESUMEN
Pharmacological agents limiting secondary tissue loss and improving functional outcomes after stroke are still limited. Cannabidiol (CBD), the major non-psychoactive component of Cannabis sativa, has been proposed as a neuroprotective agent against experimental cerebral ischemia. The effects of CBD mostly relate to the modulation of neuroinflammation, including glial activation. To investigate the effects of CBD on glial cells after focal ischemia in vivo, we performed time-lapse imaging of microglia and astroglial Ca2+ signaling in the somatosensory cortex in the subacute phase of stroke by in vivo two-photon laser-scanning microscopy using transgenic mice with microglial EGFP expression and astrocyte-specific expression of the genetically encoded Ca2+ sensor GCaMP3. CBD (10 mg/kg, intraperitoneally) prevented ischemia-induced neurological impairment, reducing the neurological deficit score from 2.0 ± 1.2 to 0.8 ± 0.8, and protected against neurodegeneration, as shown by the reduction (more than 70%) in Fluoro-Jade C staining (18.8 ± 7.5 to 5.3 ± 0.3). CBD reduced ischemia-induced microglial activation assessed by changes in soma area and total branch length, and exerted a balancing effect on astroglial Ca2+ signals. Our findings indicate that the neuroprotective effects of CBD may occur in the subacute phase of ischemia, and reinforce its strong anti-inflammatory property. Nevertheless, its mechanism of action on glial cells still requires further studies.
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Cannabidiol , Fármacos Neuroprotectores , Accidente Cerebrovascular , Animales , Ratones , Cannabidiol/farmacología , Cannabidiol/uso terapéutico , Cannabidiol/metabolismo , Neuroglía , Microglía/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Fármacos Neuroprotectores/metabolismo , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/metabolismoRESUMEN
Phosphodiesterase 4 (PDE4) inhibitors have been shown to present beneficial effects in cerebral ischemic injury because of their ability to improve cognition and target different phases and mechanisms of cerebral ischemia, including apoptosis, neurogenesis, angiogenesis, and inflammation. The present study investigated whether repeated treatment with the PDE4 inhibitor roflumilast rescued memory loss and attenuated neuroinflammation in rats following transient global cerebral ischemia (TGCI). TGCI caused memory impairments, neuronal loss (reflected by Neuronal nuclei (NeuN) immunoreactivity), and compensatory neurogenesis (reflected by doublecortin (DCX) immunoreactivity) in the hippocampus. Also, increases in the protein expression of the phosphorylated response element-binding protein (pCREB) and inflammatory markers such as the glial fibrillary acidic protein (GFAP) and ionized calcium-binding adaptor molecule 1 (Iba-1), were detected in the hippocampus in TGCI rats. Repeated treatment with roflumilast (0.003 and 0.01 mg/kg) prevented spatial memory deficits without promoting hippocampal protection in ischemic animals. Roflumilast increased the levels of pCREB, arginase-1, interleukin (IL) 4, and IL-10 in the hippocampus 21 days after TGCI. These data suggest a protective effect of roflumilast against functional sequelae of cerebral ischemia, which might be related to its anti-inflammatory properties.
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Isquemia Encefálica , Ataque Isquémico Transitorio , Aminopiridinas/farmacología , Aminopiridinas/uso terapéutico , Animales , Benzamidas , Isquemia Encefálica/tratamiento farmacológico , Ciclopropanos , Proteína Doblecortina , Hipocampo , Ratas , Memoria EspacialRESUMEN
An ever-increasing body of preclinical studies has shown the multifaceted neuroprotective profile of cannabidiol (CBD) against impairments caused by cerebral ischemia. In this study, we have explored the neuropharmacological mechanisms of CBD action and its impact on functional recovery using a model of transient global cerebral ischemia in mice. C57BL/6J mice were subjected to bilateral common carotid artery occlusion (BCCAO) for 20 min and received vehicle or CBD (10 mg/Kg) 0.5 hr before and 3, 24, and 48 hr after reperfusion. To investigate the neuropharmacological mechanisms of CBD, the animals were injected with CB1 (AM251, 1 mg/kg), CB2 (AM630, 1 mg/kg), 5-HT1A (WAY-100635, 10 mg/kg), or PPAR-γ (GW9662, 3 mg/kg) receptor antagonists 0.5 hr prior to each injection of CBD. The animals were evaluated using a multi-task testing battery that included the open field, elevated zero maze, Y-maze (YM), and forced swim test. CBD prevented anxiety-like behavior, memory impairments, and despair-like behaviors induced by BCCAO in mice. The anxiolytic-like effects of CBD in BCCAO mice were attenuated by CB1 , CB2 , 5-HT1A , and PPAR-γ receptor antagonists. In the YM, both CBD and the CB1 receptor antagonist AM251 increased the exploration of the novel arm in ischemic animals, indicating beneficial effects of these treatments in the spatial memory performance. Together, these findings indicate the involvement of CB1 , CB2 , 5-HT1A, and PPAR-γ receptors in the functional recovery induced by CBD in BCCAO mice.
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Cannabidiol , Disfunción Cognitiva , Animales , Isquemia , Ratones , Ratones Endogámicos C57BL , PPAR gamma , Receptor Cannabinoide CB1 , Receptor Cannabinoide CB2 , Receptor de Serotonina 5-HT1ARESUMEN
The clinical outcome of papillary thyroid carcinoma (PTC) patients with an indeterminate response after initial therapy is reported to be intermediate, between incomplete and excellent responses. This study evaluated the outcomes of PTC patients with indeterminate response after initial therapy. It was further determined whether the indeterminate findings predicted outcomes more precisely. Patients were further classified into 3 groups based on risk of structural persistence/recurrence: Tg group: detectable thyroglobulin, negative antithyroglobulin antibody, regardless nonspecific imaging findings; TgAb group: positive antithyroglobulin antibody, regardless thyroglobulin levels and nonspecific imaging findings, and Image group: nonspecific findings on neck ultrasonography or faint uptake in the thyroid bed on whole-body scan, undetectable thyroglobulin and negative antithyroglobulin antibody. Sixty-six patients aged 44.1±12.7 years were studied, of whom 58 (87.9%) were females. All patients underwent total thyroidectomy, and 52 patients (78.8%) received radioiodine. After 5.7 years (P25-75 2.6-9.75 years) of follow-up, most patients (89.4%) were reclassified as having an excellent response or remained in the indeterminate response to therapy. Structural recurrence/persistence disease was detected in 7 (10.6%) patients. The persistence/recurrence rate in groups were as follow: Tg, 2.63%; TgAb, 31.25%; Image, 8.3% (p=0.007). The 10-years disease-free survival rate in the TgAb group was significantly reduced (p=0.022). Our results suggest that patients with PTC and indeterminate response due to positive serum antithyroglobulin antibody have more risk of development of structural disease. These findings suggest a more individualized follow-up strategy for patients with an indeterminate response.
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Autoanticuerpos/inmunología , Tiroglobulina/inmunología , Cáncer Papilar Tiroideo/inmunología , Cáncer Papilar Tiroideo/terapia , Neoplasias de la Tiroides/inmunología , Neoplasias de la Tiroides/terapia , Adulto , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Resultado del TratamientoRESUMEN
Cognitive and affective impairments are the most characterized consequences following cerebral ischemia. BAY 60-7550, a selective phosphodiesterase type 2 inhibitor (PDE2-I), presents memory-enhancing and anxiolytic-like properties. The behavioral effects of BAY 60-7550 have been associated with its ability to prevent hydrolysis of both cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) thereby interfering with neuronal plasticity. Here, we hypothesize that PDE2-I treatment could promote functional recovery after brain ischemia. Mice C57Bl/6 were submitted to bilateral common carotid artery occlusion (BCCAO), an experimental model of transient brain ischemia, for 20 min. During 21 days after reperfusion, the animals were tested in a battery of behavioral tests including the elevated zero maze (EZM), object location task (OLT) and forced swim test (FST). The effects of BAY 60-7550 were evaluated on neuronal nuclei (NeuN), caspase-9, cAMP response element-binding protein (CREB), phosphorylated CREB (pCREB) and brain-derived neurotrophic factor (BDNF) expression in the hippocampus. BCCAO increased anxiety levels, impaired hippocampus-dependent cognitive function and induced despair-like behavior in mice. Hippocampal neurodegeneration was evidenced by a decrease in NeuN and increase incaspase-9 protein levels in BCCAO mice. Ischemic mice also showed low BDNF protein levels in the hippocampus. Repeated treatment with BAY 60-7550 attenuated the behavioral impairments induced by BCCAO in mice. Concomitantly, BAY 60-7550 enhanced expression of pCREB and BDNF protein levels in the hippocampus of ischemic mice. The present findings suggest that chronic inhibition of PDE2 provides functional recovery in BCCAO mice possibly by augmenting hippocampal neuronal plasticity.
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Isquemia Encefálica/tratamiento farmacológico , Hipocampo/efectos de los fármacos , Imidazoles/uso terapéutico , Plasticidad Neuronal , Inhibidores de Fosfodiesterasa/uso terapéutico , Triazinas/uso terapéutico , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Caspasa 9/genética , Caspasa 9/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteínas de Unión al ADN , Exonucleasas/antagonistas & inhibidores , Hipocampo/irrigación sanguínea , Imidazoles/farmacología , Masculino , Aprendizaje por Laberinto , Ratones , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/fisiología , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Inhibidores de Fosfodiesterasa/farmacología , Triazinas/farmacologíaRESUMEN
Objectives Georgia has the highest rate of maternal mortality in the United States, and ranks 40th for infant mortality. The Georgia Maternal and Infant Health Research Group was formed to investigate and address the shortage of obstetric care providers outside the Atlanta area. Because access to prenatal care (PNC) can improve maternal and infant health outcomes, we used qualitative methods to identify the access barriers experienced by women who live in rural and peri-urban areas of the state. Methods We conducted semi-structured, in-depth interviews with 24 mothers who gave birth between July and August 2013, and who live in either shortage or non-shortage obstetric care service areas. We also conducted key informant interviews with four perinatal case managers, and analyzed all data using applied thematic analysis. We then utilized Thaddeus and Maine's "Three Delays to Care" theoretical framework structure to describe the recognized barriers to care. Results We identified delays in a woman's decision to seek PNC (such as awareness of pregnancy and stigma); delays in accessing an appropriate healthcare facility (such as choosing a doctor and receiving insurance coverage); and delays in receiving adequate and appropriate care (such as continuity of care and communication). Moreover, many participants perceived low self-worth and believed this influenced their PNC exchanges. Conclusion As a means of supporting Georgia's pregnant women who face barriers and delays to PNC, these data provide a rationale for developing contextually relevant solutions to both mothers and their providers.
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Accesibilidad a los Servicios de Salud , Servicios de Salud Materna/estadística & datos numéricos , Atención Prenatal/estadística & datos numéricos , Servicios de Salud Rural/organización & administración , Servicios de Salud Suburbana/organización & administración , Femenino , Humanos , Lactante , Mortalidad Infantil , Entrevistas como Asunto , Servicios de Salud Materna/provisión & distribución , Mortalidad Materna , Madres , Aceptación de la Atención de Salud , Embarazo , Investigación Cualitativa , Población Rural , Población SuburbanaAsunto(s)
Centers for Disease Control and Prevention, U.S./organización & administración , Brotes de Enfermedades/prevención & control , Cooperación Internacional , Poliomielitis/prevención & control , Vacuna Antipolio Oral/efectos adversos , África/epidemiología , Humanos , Filipinas/epidemiología , Poliomielitis/epidemiología , Poliomielitis/virología , Estados UnidosRESUMEN
The Ebola virus disease (Ebola) outbreak in West Africa began in late 2013 in Guinea (1) and spread unchecked during early 2014. By mid-2014, it had become the first Ebola epidemic ever documented. Transmission was occurring in multiple districts of Guinea, Liberia, and Sierra Leone, and for the first time, in capital cities (2). On August 8, 2014, the World Health Organization (WHO) declared the outbreak to be a Public Health Emergency of International Concern (3). Ministries of Health, with assistance from multinational collaborators, have reduced Ebola transmission, and the number of cases is now declining. While Liberia has not reported a case since July 12, 2015, transmission has continued in Guinea and Sierra Leone, although the numbers of cases reported are at the lowest point in a year. In August 2015, Guinea and Sierra Leone reported 10 and four confirmed cases, respectively, compared with a peak of 526 (Guinea) and 1,997 (Sierra Leone) in November 2014. This report details the current situation in Guinea and Sierra Leone, outlines strategies to interrupt transmission, and highlights the need to maintain public health response capacity and vigilance for new cases at this critical time to end the outbreak.
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Brotes de Enfermedades/prevención & control , Ebolavirus/aislamiento & purificación , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , Adulto , Femenino , Guinea/epidemiología , Humanos , Sierra Leona/epidemiologíaRESUMEN
Papillary thyroid cancer (PTC), whose incidence has been increasing in the last years, occurs more frequently in women. Experimental studies suggested that estrogen could be an important risk factor for the higher female incidence. In fact, it has been demonstrated that 17ß-estradiol (E2) could increase proliferation and dedifferentiation in thyroid follicular cells. Genomic estrogen responses are typically mediated through classical estrogen receptors, the α and ß isoforms, which have been described in normal and abnormal human thyroid tissue. Nevertheless, effects mediated through G protein estrogen receptor 1 (GPR30/GPER/GPER1), described in some thyroid cancer cell lines, could be partially responsible for the regulation of growth in normal cells. In this study, GPER1 gene and protein expression are described in non-malignant and in papillary thyroid cancer (PTC), as well as its association with clinical features of patients with PTC. The GPER1 expression was lower in PTC as compared to paired non-malignant thyroid tissues in fresh samples of PTC and in silico analysis of GEO and TCGA databases. In PTC cases of TCGA database, low GPER1 mRNA expression was independently associated with metastatic lymph nodes, female gender, and BRAF mutation. Besides, GPER1 mRNA levels were positively correlated with mRNA levels of thyroid differentiation genes. These results support the hypothesis that GPER1 have a role in PTC tumorigenesis and might be a potential target for its therapy. Further studies are needed to determine the functionality of these receptors in normal and diseased thyroid.
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Biología Computacional/métodos , Regulación hacia Abajo , Receptores de Estrógenos/genética , Receptores Acoplados a Proteínas G/genética , Cáncer Papilar Tiroideo/genética , Neoplasias de la Tiroides/genética , Estudios de Casos y Controles , Bases de Datos Genéticas , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis Linfática , Masculino , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Caracteres SexualesRESUMEN
Evidence for the clinical use of neuroprotective drugs for the treatment of cerebral ischemia (CI) is still greatly limited. Spatial/temporal disorientation and cognitive dysfunction are among the most prominent long-term sequelae of CI. Cannabidiol (CBD) is a non-psychotomimetic constituent of Cannabis sativa that exerts neuroprotective effects against experimental CI. The present study investigated possible neuroprotective mechanisms of action of CBD on spatial memory impairments that are caused by transient global cerebral ischemia (TGCI) in rats. Hippocampal synaptic plasticity is a fundamental mechanism of learning and memory. Thus, we also evaluated the impact of CBD on neuroplastic changes in the hippocampus after TGCI. Wistar rats were trained to learn an eight-arm aversive radial maze (AvRM) task and underwent either sham or TGCI surgery. The animals received vehicle or 10 mg/kg CBD (i.p.) 30 min before surgery, 3 h after surgery, and then once daily for 14 days. On days 7 and 14, we performed a retention memory test. Another group of rats that received the same pharmacological treatment was tested in the object location test (OLT). Brains were removed and processed to assess neuronal degeneration, synaptic protein levels, and dendritic remodeling in the hippocampus. Cannabidiol treatment attenuated ischemia-induced memory deficits. In rats that were subjected to TGCI, CBD attenuated hippocampal CA1 neurodegeneration and increased brain-derived neurotrophic factor levels. Additionally, CBD protected neurons against the deleterious effects of TGCI on dendritic spine number and the length of dendritic arborization. These results suggest that the neuroprotective effects of CBD against TGCI-induced memory impairments involve changes in synaptic plasticity in the hippocampus.
Asunto(s)
Cannabidiol/uso terapéutico , Hipocampo/efectos de los fármacos , Ataque Isquémico Transitorio/prevención & control , Plasticidad Neuronal/efectos de los fármacos , Neuroprotección/efectos de los fármacos , Sinapsis/efectos de los fármacos , Animales , Cannabidiol/farmacología , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Hipocampo/patología , Ataque Isquémico Transitorio/metabolismo , Ataque Isquémico Transitorio/patología , Masculino , Plasticidad Neuronal/fisiología , Neuroprotección/fisiología , Técnicas de Cultivo de Órganos , Ratas , Ratas Wistar , Memoria Espacial/efectos de los fármacos , Memoria Espacial/fisiología , Sinapsis/metabolismo , Sinapsis/patologíaRESUMEN
The present study investigated the pharmacological mechanisms of the antidepressant-like effects of amantadine in mice and their influence on hippocampal neurogenesis. To improve the translational validity of preclinical results, reproducibility across laboratories and replication in other animal models and species are crucial. Single amantadine administration at doses of 50 and 75 mg/kg resulted in antidepressant-like effects in mice in the tail suspension test (TST), reflected by an increase in immobility time. The effects of amantadine were seen at doses that did not alter locomotor activity. The tyrosine hydroxylase inhibitor α-methyl-ρ-tyrosine did not influence the anti-immobility effect of amantadine in the TST. Pretreatment with the α1 adrenergic receptor antagonist prazosin, ß adrenergic receptor antagonist propranolol, α2 adrenergic receptor antagonist yohimbine, and α2 adrenergic receptor agonist clonidine did not alter the antidepressant-like effect of amantadine. However, amantadine's effect was blocked by the dopamine D2 receptor antagonist haloperidol and glutamate receptor agonist N-methyl-D-aspartate (NMDA). Repeated amantadine administration (50 mg/kg) also exerted an antidepressant-like effect, paralleled by an increase in hippocampal neurogenesis. The present results demonstrate that the antidepressant-like effects of amantadine may be mediated by its actions on D2 and NMDA receptors and likely involve hippocampal neurogenesis.
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Agonistas Adrenérgicos/farmacología , Antagonistas Adrenérgicos/farmacología , Amantadina/farmacología , Antidepresivos/farmacología , Conducta Animal/efectos de los fármacos , Agonistas de Aminoácidos Excitadores/farmacología , Receptores de Dopamina D2/efectos de los fármacos , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Amantadina/administración & dosificación , Animales , Antidepresivos/administración & dosificación , Inhibidores Enzimáticos/farmacología , Hipocampo/efectos de los fármacos , Masculino , Ratones , Neurogénesis/efectos de los fármacos , alfa-Metiltirosina/farmacologíaRESUMEN
NG2 is a type I transmembrane glycoprotein known as chondroitin sulfate proteoglycan 4 (CSPG4). In the healthy central nervous system, NG2 is exclusively expressed by oligodendrocyte progenitor cells and by vasculature pericytes. A large body of immunohistochemical studies showed that under pathological conditions such as acute brain injuries and experimental autoimmune encephalomyelitis (EAE), a number of activated microglia were NG2 immuno-positive, suggesting NG2 expression in these cells. Alternative explanations for the microglial NG2 labeling consider the biochemical properties of NG2 or the phagocytic activity of activated microglia. Reportedly, the transmembrane NG2 proteoglycan can be cleaved by a variety of proteases to deposit the NG2 ectodomain into the extracellular matrix. The ectodomain, however, could also stick to the microglial surface. Since microglia are phagocytic cells engulfing debris of dying cells, it is difficult to identify a genuine expression of NG2. Recent studies showing (1) pericytes giving rise to microglial after stroke, and (2) immune cells of NG2-EYFP knock-in mice lacking NG2 expression in an EAE model generated doubts for the de novo expression of NG2 in microglia after acute brain injuries. In the current study, we took advantage of three knock-in mouse lines (NG2-CreERT2, CX3CR1-EGFP and NG2-EYFP) to study NG2 expression indicated by transgenic fluorescent proteins in microglia after tMCAO (transient middle cerebral artery occlusion) or cortical stab wound injury (SWI). We provide strong evidence that NG2-expressing cells, including OPCs and pericytes, did not differentiate into microglia after acute brain injuries, whereas activated microglia did express NG2 in a disease-dependent manner. A subset of microglia continuously activated the NG2 gene at least within the first week after tMCAO, whereas within 3 days after SWI a limited number of microglia at the lesion site transiently expressed NG2. Immunohistochemical studies demonstrated that these microglia with NG2 gene activity also synthesized the NG2 protein, suggesting activated microglia as an additional source of the NG2 proteoglycan after acute brain injuries.
Asunto(s)
Antígenos/metabolismo , Lesiones Encefálicas/metabolismo , Microglía/metabolismo , Proteoglicanos/metabolismo , Animales , Técnicas de Sustitución del Gen , Ratones , Ratones TransgénicosRESUMEN
Pharmacological interventions that selectively activate serotonin 5-hydroxytryptramine-1A (5-HT1A) heteroreceptors may prevent or attenuate the consequences of brain ischemic episodes. The present study investigated whether the preferential 5-HT1A postsynaptic receptor agonist NLX-101 (a.k.a. F15599) mitigates cognitive and emotional impairments and affects neuroplasticity in mice that are subjected to the bilateral common carotid artery occlusion (BCCAO) model of brain ischemia. The selective serotonin reuptake inhibitor escitalopram (Esc) was used for comparative purposes because it is able to decrease morbidity and improve recovery in stroke patients and ischemic rodents. Sham and BCCAO mice received daily doses of NLX-101 (0.32 mg/kg, i.p) or Esc (20 mg/kg, i.p) for 28 days. During this period, they were evaluated for locomotor activity, anxiety- and despair-related behaviors and hippocampus-dependent cognitive function, using the open field, elevated zero maze, forced swim test and object location test, respectivelly. The mice's brains were processed for biochemical and histological analyses. BCCAO mice exhibited high anxiety and despair-like behaviors and performed worse than controls in the cognitive assessment. BCCAO induced neuronal and dendritic spine loss and decreases in the protein levels of neuronal plasticity markers, including brain-derived neurotrophic factor (BDNF), synaptophysin (SYN), and postsynaptic density protein-95 (PSD-95), in prefrontal cortex (PFC) and hippocampus. NLX-101 and Esc attenuated cognitive impairments and despair-like behaviors in BCCAO mice. Only Esc decreased anxiety-like behaviors due to brain ischemia. Both NLX-101 and Esc blocked the increase in plasma corticosterone levels and, restored BDNF, SYN and PSD-95 protein levels in the hippocampus. Moreover, both compounds impacted positively dentritic remodeling in the hippocampus and PFC of ischemic mice. In the PFC, NLX-101 increased the BDNF protein levels, while Esc in turn, attenuated the decrease in the PSD-95 protein levels induced by BCCAO. The present results suggest that activation of post-synaptic 5-HT1A receptors is the molecular mechanism for serotonergic protective effects in BCCAO. Moreover, post-synaptic biased agonists such as NLX-101 might constitute promising therapeutics for treatment of functional and neurodegenerative outcomes of brain ischemia.
Asunto(s)
Isquemia Encefálica/metabolismo , Plasticidad Neuronal/efectos de los fármacos , Piperidinas/uso terapéutico , Pirimidinas/uso terapéutico , Receptor de Serotonina 5-HT1A/metabolismo , Recuperación de la Función/efectos de los fármacos , Agonistas del Receptor de Serotonina 5-HT1/uso terapéutico , Animales , Isquemia Encefálica/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos C57BL , Plasticidad Neuronal/fisiología , Piperidinas/farmacología , Pirimidinas/farmacología , Recuperación de la Función/fisiología , Agonistas del Receptor de Serotonina 5-HT1/farmacologíaRESUMEN
The incidence of papillary thyroid carcinoma (PTC) has been increasing, which raised the interest in its molecular pathways. Although the high expression of ecto-5'-nucleotidase (NT5E) gene expression and NT5E enzymatic activity in several types of cancer is associated with tumor progression, its role in PTC remains unknown. Here, we investigated the AMP hydrolysis in human normal thyroid cells and PTC cells, in primary culture, and the association of NT5E expression with clinical aspects of PTC patients. AMPase activity was higher in thyroid cells isolated from PTC, as compared to normal thyroid (Pâ¯=â¯0.0063). Significant correlation was observed between AMPase activity and NT5E levels in primary thyroid cell cultures (râ¯=â¯0.655, Pâ¯=â¯0.029). NT5E expression was higher in PTC than in the adjacent non-malignant thyroid tissue (Pâ¯=â¯0.0065) and were positively associated with metastatic lymph nodes (Pâ¯=â¯0.0007), risk of recurrence (Pâ¯=â¯0.0033), tumor size (Pâ¯=â¯0.049), and nodular hyperplasia in the adjacent thyroid parenchyma, when compared to normal thyroid or lymphocytic thyroiditis (Pâ¯=â¯0.0146). After adjusting for potential confounders, the malignant/non-malignant paired expression ratio of NT5E mRNA was independently associated with metastatic lymph nodes (Pâ¯=â¯0.0005), and tumor size (P=0.0005). In addition, the analysis of PTC described in the TCGA database also showed an association between higher expression of NT5E and metastatic lymph nodes, and tumor microinvasion. These results support the hypothesis that NT5E have a role in PTC microenvironment and might be a potential target for PTC therapy.
Asunto(s)
5'-Nucleotidasa/metabolismo , Ganglios Linfáticos/enzimología , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Cáncer Papilar Tiroideo/enzimología , Cáncer Papilar Tiroideo/patología , 5'-Nucleotidasa/genética , Línea Celular Tumoral , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Persona de Mediana Edad , Nucleotidasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Cáncer Papilar Tiroideo/genética , Glándula Tiroides/patologíaRESUMEN
Type II deiodinase (D2) plays a critical role in controlling intracellular T3 concentration and early studies indicated a follicular but not a parafollicular C-cell origin of D2 activity in the thyroid gland. Here, we show that D2 is highly expressed in human medullary thyroid carcinoma (MTC), a tumor that arises from the C-cells. D2 transcripts were detected in all MTC samples obtained from 12 unselected MTC patients and the levels of D2 activity were comparable to those found in surrounding normal follicular tissue (0.41+/-0.10 fmol min mg protein vs. 0.43+/-0.41 fmol min mg protein, P=0.91). Additional analysis in the TT cells, a human MTC cell line, demonstrated that the D2 expression is downregulated by thyroid hormones and enhanced by cAMP analogs and dexamethasone. The thyroid hormone receptor alpha1 and beta isoforms were also detected in all MTC samples and in TT cells, thus suggesting a potential role of T3 locally produced by D2 in this neoplastic tissue.