RESUMEN
A minority of individuals experiencing traumatic events develop anxiety disorders. The reason for the lack of correspondence between the prevalence of exposure to psychological trauma and the development of anxiety is unknown. Extracellular proteolysis contributes to fear-associated responses by facilitating neuronal plasticity at the neuron-matrix interface. Here we show in mice that the serine protease neuropsin is critical for stress-related plasticity in the amygdala by regulating the dynamics of the EphB2-NMDA-receptor interaction, the expression of Fkbp5 and anxiety-like behaviour. Stress results in neuropsin-dependent cleavage of EphB2 in the amygdala causing dissociation of EphB2 from the NR1 subunit of the NMDA receptor and promoting membrane turnover of EphB2 receptors. Dynamic EphB2-NR1 interaction enhances NMDA receptor current, induces Fkbp5 gene expression and enhances behavioural signatures of anxiety. On stress, neuropsin-deficient mice do not show EphB2 cleavage and its dissociation from NR1 resulting in a static EphB2-NR1 interaction, attenuated induction of the Fkbp5 gene and low anxiety. The behavioural response to stress can be restored by intra-amygdala injection of neuropsin into neuropsin-deficient mice and disrupted by the injection of either anti-EphB2 antibodies or silencing the Fkbp5 gene in the amygdala of wild-type mice. Our findings establish a novel neuronal pathway linking stress-induced proteolysis of EphB2 in the amygdala to anxiety.
Asunto(s)
Amígdala del Cerebelo/metabolismo , Ansiedad/metabolismo , Calicreínas/metabolismo , Receptor EphB2/metabolismo , Amígdala del Cerebelo/citología , Animales , Ansiedad/genética , Trastornos de Ansiedad/etiología , Trastornos de Ansiedad/genética , Trastornos de Ansiedad/metabolismo , Conductividad Eléctrica , Miedo , Regulación de la Expresión Génica , Calicreínas/deficiencia , Calicreínas/genética , Potenciación a Largo Plazo , Ratones , Ratones Endogámicos C57BL , Plasticidad Neuronal , Neuronas/metabolismo , Unión Proteica , Receptor EphB2/química , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/metabolismo , Estrés Psicológico/metabolismo , Proteínas de Unión a Tacrolimus/genéticaRESUMEN
Severe psychological trauma triggers genetic, biochemical and morphological changes in amygdala neurons, which underpin the development of stress-induced behavioural abnormalities, such as high levels of anxiety. miRNAs are small, non-coding RNA fragments that orchestrate complex neuronal responses by simultaneous transcriptional/translational repression of multiple target genes. Here we show that miR-483-5p in the amygdala of male mice counterbalances the structural, functional and behavioural consequences of stress to promote a reduction in anxiety-like behaviour. Upon stress, miR-483-5p is upregulated in the synaptic compartment of amygdala neurons and directly represses three stress-associated genes: Pgap2, Gpx3 and Macf1. Upregulation of miR-483-5p leads to selective contraction of distal parts of the dendritic arbour and conversion of immature filopodia into mature, mushroom-like dendritic spines. Consistent with its role in reducing the stress response, upregulation of miR-483-5p in the basolateral amygdala produces a reduction in anxiety-like behaviour. Stress-induced neuromorphological and behavioural effects of miR-483-5p can be recapitulated by shRNA mediated suppression of Pgap2 and prevented by simultaneous overexpression of miR-483-5p-resistant Pgap2. Our results demonstrate that miR-483-5p is sufficient to confer a reduction in anxiety-like behaviour and point to miR-483-5p-mediated repression of Pgap2 as a critical cellular event offsetting the functional and behavioural consequences of psychological stress.
Asunto(s)
Complejo Nuclear Basolateral , MicroARNs , Animales , Masculino , Ratones , Amígdala del Cerebelo/metabolismo , Complejo Nuclear Basolateral/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Neuronas/metabolismo , Sinapsis/metabolismoRESUMEN
The organization of eukaryotic genome in the nucleus, a double-membraned organelle separated from the cytoplasm, is highly complex and dynamic. The functional architecture of the nucleus is confined by the layers of internal and cytoplasmic elements, including chromatin organization, nuclear envelope associated proteome and transport, nuclear-cytoskeletal contacts, and the mechano-regulatory signaling cascades. The size and morphology of the nucleus could impose a significant impact on nuclear mechanics, chromatin organization, gene expression, cell functionality and disease development. The maintenance of nuclear organization during genetic or physical perturbation is crucial for the viability and lifespan of the cell. Abnormal nuclear envelope morphologies, such as invagination and blebbing, have functional implications in several human disorders, including cancer, accelerated aging, thyroid disorders, and different types of neuro-muscular diseases. Despite the evident interplay between nuclear structure and nuclear function, our knowledge about the underlying molecular mechanisms for regulation of nuclear morphology and cell functionality during health and illness is rather poor. This review highlights the essential nuclear, cellular, and extracellular components that govern the organization of nuclei and functional consequences associated with nuclear morphometric aberrations. Finally, we discuss the recent developments with diagnostic and therapeutic implications targeting nuclear morphology in health and disease.
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Núcleo Celular , Membrana Nuclear , Humanos , Núcleo Celular/metabolismo , Membrana Nuclear/metabolismo , Citoplasma/metabolismo , Citoesqueleto , Cromatina/metabolismoRESUMEN
In published studies, cohorts of patients with bacteremia due to vancomycin-resistant Enterococcus (VRE) have predominantly been infected with Enterococcus faecium. Little is known about the epidemiology and outcomes associated with bacteremia due to VR Enterococcus faecalis. A retrospective study of isolates obtained from January 2008 to October 2010 was conducted at Detroit Medical Center (DMC). Unique patients with blood cultures positive for VRE were reviewed. Outcomes were analyzed using logistic regression. During the study period, 105 cases of bacteremia due to VR E. faecalis and 197 cases of bacteremia due to VR E. faecium were identified. The mean age in the study cohort was 61.5 ± 15 years; 162 subjects (53.6%) were male. After controlling for a propensity score, bacteremia due to VR E. faecalis was associated with >2-fold-lower in-hospital mortality than bacteremia due to VR E. faecium. Interestingly, bacteremia due to VR E. faecalis was associated with longer hospital stay after VRE isolation, although total length of stay was similar for groups with VR E. faecalis and VR E. faecium. Bacteremia due to VR E. faecalis was associated with a >2-fold-lower risk for mortality than bacteremia due to VR E. faecium, possibly due to the availability of ß-lactam therapeutics for treatment of VR E. faecalis.
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Antibacterianos/administración & dosificación , Bacteriemia/tratamiento farmacológico , Enterococcus faecalis/patogenicidad , Enterococcus faecium/patogenicidad , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Vancomicina/administración & dosificación , beta-Lactamas/administración & dosificación , Adulto , Anciano , Antibacterianos/uso terapéutico , Bacteriemia/epidemiología , Bacteriemia/microbiología , Bacteriemia/mortalidad , Enterococcus faecalis/aislamiento & purificación , Enterococcus faecium/aislamiento & purificación , Femenino , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/mortalidad , Mortalidad Hospitalaria , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Estados Unidos/epidemiología , Vancomicina/uso terapéutico , Resistencia a la Vancomicina , beta-Lactamas/uso terapéuticoRESUMEN
The triplication of genes located on chromosome 21 is known to cause a wide spectrum of pathology seen in Down syndrome (DS), including leukemia, seizures, stroke, and mental retardation. Studies on RNA and protein expression of genes in DS brain have demonstrated the role of triplicated genes in several DS phenotypes. Significant changes in the expression of nontriplicated genes have also been observed. However, little information is available regarding the role of nonchromosome 21 genes in DS pathology. We have found that α-synuclein (SNCA), a presynaptic protein whose gene is located on chromosome 6 in the Ts65Dn mouse model for DS, is significantly reduced in the cortex and other brain regions. We hypothesize that this alteration may play a critical role in the reduced synaptic function observed in DS. We have found an increase in the level of neurosin, a key negative regulator of SNCA in Ts65Dn cortex. We have also found increased levels of protein phosphatase 2A, a negative regulator of the activation of tyrosine hydroxylase and a key enzyme in the biosynthetic pathway for dopamine in Ts65Dn cortex. These findings reveal potential target sites for intervention in the treatment of DS pathology.
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Encéfalo/metabolismo , Síndrome de Down/metabolismo , Calicreínas/metabolismo , Transmisión Sináptica/fisiología , alfa-Sinucleína/biosíntesis , Adolescente , Adulto , Anciano , Animales , Western Blotting , Encéfalo/fisiopatología , Modelos Animales de Enfermedad , Síndrome de Down/fisiopatología , Humanos , Inmunohistoquímica , Ratones , Persona de Mediana Edad , Proteína Fosfatasa 2/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Adulto JovenRESUMEN
PURPOSE: To estimate the contribution of the flexor pollicis longus (FPL) to key pinch strength. Secondary outcomes include tip pinch, 3-point chuck pinch, and grip strength. METHODS: Eleven healthy volunteers consented to participate in the study. We recorded baseline measures for key, 3-point chuck, and tip pinch and for grip strength. In order to control for instability of the interphalangeal (IP) joint after FPL paralysis, pinch measurements were repeated after immobilizing the thumb IP joint. Measures were repeated after subjects underwent electromyography-guided lidocaine blockade of the FPL muscle. Nerve conduction studies and clinical examinations were used to confirm FPL blockade and to rule out median nerve blockade. Paired t-tests were used to compare pre- and postblock means for both unsplinted and splinted measures. The difference in means was used to estimate the contribution of FPL to pinch strength. RESULTS: All 3 types of pinch strength showed a significant decrease between pre- and postblock measurements. The relative contribution of FPL for each pinch type was 56%, 44%, and 43% for key, chuck, and tip pinch, respectively. Mean grip strength did not decrease significantly. Splinting of the IP joint had no significant effect on pinch measurements. CONCLUSIONS: FPL paralysis resulted in a statistically significant decrease in pinch strength. IP joint immobilization to simulate IP joint fusion did not affect results. CLINICAL RELEVANCE: Reconstruction after acute or chronic loss of FPL function should be considered when restoration of pinch strength is important.
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Articulaciones de los Dedos/fisiología , Tendones/fisiología , Pulgar/fisiología , Adulto , Femenino , Fuerza de la Mano , Humanos , Inmovilización , Masculino , Conducción Nerviosa/fisiología , Paresia/fisiopatología , Férulas (Fijadores) , Adulto JovenRESUMEN
Rosuvastatin, a second generation 3-Hydroxy-3-Methyl Glutaryl Coenzyme-A reductase inhibitor, is widely used for the management of hypercholesterolemia. Rosuvastatin ethanolamine, developed by Cadila Healthcare Ltd., is a novel, chemically stable, and pharmaceutically acceptable salt, having better physiochemical properties than commercially available Rosuvastatin salt. The objective of the present study is to evaluate safety, tolerability, and toxicokinetic profile of novel salt. Therefore, four weeks repeated dose oral (gavage) toxicity and toxicokinetic study of Rosuvastatin ethanolamine was carried out. The drugs were administered once daily at salt corrected dose of 15, 40, and 100 mg/kg for four weeks. No signs of toxicity were observed during repeated (four weeks) oral administrations of Rosuvastatin ethanolamine in rats up to 40 mg/kg. Single male mortality was observed at 100 mg/kg dose. Microscopy finding in liver was minimal to mild bile ductular proliferation, single cell necrosis, and hepatocellular vacuolation of cytoplasm with associated statistically significant serum elevation of transaminase enzymes; AST, ALT, ALP, and/or liver functional marker; total bilirubin with at ≥40 mg/kg. The systemic exposures (AUC0-24 and Cmax) were not markedly different between males and females, or between the administration periods (except high dose, where exposure on day 28 was approximately 2 to 3 fold higher than that of day 1. In conclusion, Rosuvastatin ethanolamine exhibited toxicities to liver as the target organ at ≥40 mg/kg in this study. These adverse effects with associated exposures should be taken into consideration for the future assessing of potential Rosuvastatin toxicities.
RESUMEN
Obesity has been increasingly recognized as a risk factor for kidney disease and both proteinuria and microalbuminuria have been associated with obesity. The actual prevalence of microalbuminuria and proteinuria in obese patients in the United States (US) has not been clearly described in the literature. Furthermore, obesity is associated with risk factors of kidney disease, such as diabetes and hypertension (HTN), and the prevalence of proteinuria and albuminuria excluding these risk factors is uncertain. In this study, we collected urine albumin/creatinine and urine protein/creatinine ratios on obese patients undergoing bariatric surgery to determine the prevalence of albuminuria and proteinuria in obese patients with and without associated diabetes and HTN. The study included 218 obese patients undergoing bariatric surgery at a New York City hospital. The mean age was 42.1 ± 11.3 years. The mean body mass index (BMI) was 43.9 ± 8.1. Diabetes (DM) was present in 25%. HTN was present in 47%. The prevalence of proteinuria and albuminuria was 21% (95% CI: 15.8-27.1%) and 19.7% (95% CI: 14.2-26.2%) respectively. Among those without DM but who had HTN, 22.6% (95% CI: 12.9-35) had proteinuria and 17% (95% CI 8.4-30.9) had albuminuria. Of patients with neither DM nor HTN, 13.3% (95% CI: 7.3-21.6) and 11% (95% CI: 5-17%) had proteinuria and albuminuria, respectively. Diabetics had a significantly higher prevalence of proteinuria and albuminuria than the non-diabetic groups. The non-diabetic groups did not differ significantly from each other in terms of prevalence of proteinuria and albuminuria. The BMI for diabetics did not differ from non-diabetics. On multivariate analysis, only the presence of diabetes was associated with proteinuria and albuminuria. BMI, age, and HTN were not predictive. In conclusion, we found a relatively high prevalence of microalbuminuria and proteinuria in an urban, US, obese population undergoing bariatric surgery. When diabetics were excluded, there was a lower prevalence. Even patients who had neither diabetes nor HTN, still, however, had much greater amounts than seen in the general US population, likely reflecting an adverse effect of obesity itself on renal physiology.
RESUMEN
PURPOSE: The use of lung ultrasound (LUS) to identify extravascular lung water has received increasing acceptance. Sonographic B-lines, discrete vertical lines that originate from the pleura, represent pulmonary edema and are correlated with the accumulation of fluid. The goal of this study was to evaluate the utility of LUS to determine the accuracy of prescribed dry weight (DW) in chronic hemodialysis (HD) patients and to ascertain the adequacy of fluid removal. METHODS: LUS was scheduled to be performed pre- and post-HD in 20 patients. The HD prescription and DW challenge were done independent of the results of the LUS. The presence of B-lines was tabulated and compared to the intradialytic ultrafiltration parameters. RESULTS: Of the 20 patients, 3 did not exhibit B-lines at the first dialysis session. In regard to the other 17 patients, B-lines disappeared in 7 patients at the end of the HD session (mean B-lines 4.2-0). One patient was 0.3 kg away from the prescribed dry weight, but the 6 patients were a mean of 1.7 kg below DW. Of the remaining 10 patients, eight decreased but did not eliminate the B-lines (mean B-lines 15.5-3.8) and were a mean of 3.8 kg below DW post-HD. Two patients who exhibited more cardiac insufficiency than initially recognized could not reach DW or eliminate the B-lines. Eight patients who had residual B-lines at the end of the first HD session had their DW re-estimated and had a second session. Two were able to eliminate the B-lines (mean 2.5-0) and reached a mean of 1.2 kg below DW. Six did not eliminate the B-lines (mean 11.5-4.2) but were able to reach a mean of 0.6 kg below DW. Correlation analysis showed a statistically significant correlation (P < 0.05) between the intradialytic percent change in B-lines and the percent change in total body weight (r = 0.40) and ultrafiltration rate (r = 0.33). Seven of 10 patients with clear chest X-rays pre-HD exhibited B-lines. CONCLUSIONS: This study supports the hypothesis that reduction in B-lines during HD can provide accurate information regarding changes in pulmonary fluid content. Further, LUS is a valuable diagnostic tool for recognizing both the adequacy of fluid removal and the occurrence of error in the estimation of dry weight by usual clinical parameters.
Asunto(s)
Líquidos Corporales/diagnóstico por imagen , Fallo Renal Crónico/terapia , Pulmón/diagnóstico por imagen , Diálisis Renal , Ultrasonografía , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Edema Pulmonar/diagnóstico por imagenRESUMEN
PML is a tumor suppressor protein involved in the pathogenesis of promyelocytic leukemia. In non-neuronal cells, PML is a principal component of characteristic nuclear bodies. In the brain, PML has been implicated in the control of embryonic neurogenesis, and in certain physiological and pathological phenomena in the adult brain. Yet, the cellular and subcellular localization of the PML protein in the brain, including its presence in the nuclear bodies, has not been investigated comprehensively. Because the formation of PML bodies appears to be a key aspect in the function of the PML protein, we investigated the presence of these structures and their anatomical distribution, throughout the adult mouse brain. We found that PML is broadly expressed across the gray matter, with the highest levels in the cerebral and cerebellar cortices. In the cerebral cortex PML is present exclusively in neurons, in which it forms well-defined nuclear inclusions containing SUMO-1, SUMO 2/3, but not Daxx. At the ultrastructural level, the appearance of neuronal PML bodies differs from the classic one, i.e., the solitary structure with more or less distinctive capsule. Rather, neuronal PML bodies have the form of small PML protein aggregates located in the close vicinity of chromatin threads. The number, size, and signal intensity of neuronal PML bodies are dynamically influenced by immobilization stress and seizures. Our study indicates that PML bodies are broadly involved in activity-dependent nuclear phenomena in adult neurons.
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Encéfalo/metabolismo , Neuronas/metabolismo , Proteína de la Leucemia Promielocítica/metabolismo , Animales , Corteza Cerebral/metabolismo , Cuerpos de Inclusión Intranucleares/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Proteína SUMO-1/metabolismo , Convulsiones/metabolismo , Estrés Psicológico/metabolismoRESUMEN
Eph receptors have been the subject of intense research since their discovery. Their widespread pattern of expression, involvement in a variety of important cellular phenomena and unique mode of action have stimulated interest in their role in health and disease across biological and medical domains. However, the function of Ephs in nervous system development and plasticity remains the best characterised. Recent advances suggest that Ephs play an important role in the development of brain pathologies. This review focuses on their basic structure and function and discusses the latest research on their role in neurological diseases.