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1.
Ther Adv Neurol Disord ; 17: 17562864241253917, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38813521

RESUMEN

Opportunistic viral infections in individuals with severe immunodeficiency can lead to fatal conditions such as progressive multifocal leukoencephalopathy (PML), for which treatment options are limited. These infections pose significant risks, especially when co-infections with other viruses occur. We describe a combined therapy approach using directly isolated allogeneic Human Polyomavirus 1 (also known as BKV) and Epstein-Barr virus (EBV) specific cytotoxic T-cells for the treatment of PML in conjunction with identified EBV in the cerebrospinal fluid (CSF) of a male patient infected with human immunodeficiency virus (HIV). A 53-year-old HIV-positive male, recently diagnosed with PML, presented with rapidly worsening symptoms, including ataxia, tetraparesis, dysarthria, and dysphagia, leading to respiratory failure. The patient developed PML even after commencing highly active antiretroviral therapy (HAART) 3 months prior. Brain magnetic resonance imaging (MRI) revealed multifocal demyelination lesions involving the posterior fossa and right thalamus suggestive of PML. In addition to the detection of human polyomavirus 2 (also known as JCV), analysis of CSF showed positive results for EBV deoxyribonucleic acid (DNA). His neurological condition markedly deteriorated over the following 2 months. Based on MRI, there was no evidence of Immune Reconstitution Inflammatory Syndrome contributing to this decline. The patient did not have endogenous virus-specific T-cells. We initiated an allogeneic, partially human leukocyte antigen-matched transfer of EBV and utilizing the cross-reactivity between BKV and JCV-BKV specific T-cells. This intervention led to notable neurological improvement and partial resolution of the MRI lesions within 6 weeks. Our case of a patient with acquired immune deficiency syndrome demonstrates that PML and concurrent EBV co-infection can still occur despite undergoing HAART treatment. This innovative experimental therapy, involving a combination of virus-specific T-cells, was demonstrated to be an effective treatment option in this patient.

2.
J Membr Biol ; 256(3): 257-269, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36995425

RESUMEN

The L-type calcium current (ICaL) is the first step in cardiac excitation-contraction-coupling and plays an important role in regulating contractility, but also in electrical and mechanical remodeling. Primary culture of cardiomyocytes, a widely used tool in cardiac ion channel research, is associated with substantial morphological, functional and electrical changes some of which may be prevented by electrical pacing. We therefore investigated ICaL directly after cell isolation and after 24 h of primary culture with and without regular pacing at 1 and 3 Hz in rat left ventricular myocytes. Moreover, we analyzed total mRNA expression of the pore forming subunit of the L-type Ca2+ channel (cacna1c) as well as the expression of splice variants of its exon 1 that contribute to specificity of ICaL in different tissue such as cardiac myocytes or smooth muscle. 24 h incubation without pacing decreased ICaL density by ~ 10% only. Consistent with this decrease we observed a decrease in the expression of total cacna1c and of exon 1a, the dominant variant of cardiomyocytes, while expression of exon 1b and 1c increased. Pacing for 24 h at 1 and 3 Hz led to a substantial decrease in ICaL density by 30%, mildly slowed ICaL inactivation and shifted steady-state inactivation to more negative potentials. Total cacna1c mRNA expression was substantially decreased by pacing, as was the expression of exon 1b and 1c. Taken together, electrical silence introduces fewer alterations in ICaL density and cacna1c mRNA expression than pacing for 24 h and should therefore be the preferred approach for primary culture of cardiomyocytes.


Asunto(s)
Ventrículos Cardíacos , Miocitos Cardíacos , Ratas , Animales , Miocitos Cardíacos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Canales de Calcio Tipo L/genética , Canales de Calcio Tipo L/metabolismo
3.
Ther Adv Neurol Disord ; 14: 1756286421993684, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34035834

RESUMEN

The reactivation of human JC polyoma virus (JCPyV) results in lytic infection of oligodendrocytes and neuronal cells. The corresponding clinical picture is called progressive multifocal leukoencephalopathy (PML) and results mostly from a disease-related or drug-induced immunosuppression. The opportunistic brain infection leads to a progressive demyelination of multiple areas of the central nervous system. Patients can present with various neurological deficits ranging from slight motoric symptoms to marked aphasia or reduced vigilance. Currently, there is no effective causal therapy for PML. Survival depends on the ability to achieve timely immune reconstitution. If the immune system cannot be restored, PML progresses rapidly and often ends fatally within months. Recently, some evidence for positive response has been reported in patients treated with immune checkpoint inhibitor therapy. Here, we provide a case series of three PML patients with underlying hematological malignancies who were treated with anti-PD-1-antibody pembrolizumab at Hannover Medical School. All patients received an extensive diagnostic follow-up including cerebrospinal fluid analysis, brain imaging, and lymphocyte-phenotyping via flow cytometry. Our patients had very different outcomes, with the only patient showing a specific anti-JCPyV immune response in the sense of an increased JCPyV antibody index clearly benefiting most from the treatment. Our results partly support the hypothesis that anti-PD-1 therapy may represent a promising treatment option for patients with PML. However, there is a current lack of pre-therapeutic stratification regarding the therapeutic response rates. Before larger studies can be initiated to further evaluate the efficacy of anti-PD-1 antibodies in PML, it is imperative to develop a reliable strategy for selecting suitable patients.

4.
Basic Res Cardiol ; 114(6): 47, 2019 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-31673803

RESUMEN

A major contributor to contractile dysfunction in heart failure is remodelling and loss of the cardiomyocyte transverse tubular system (t-system), but underlying mechanisms and signalling pathways remain elusive. It has been shown that dexamethasone promotes t-tubule development in stem cell-derived cardiomyocytes and that cardiomyocyte-specific glucocorticoid receptor (GR) knockout (GRKO) leads to heart failure. Here, we studied if the t-system is altered in GRKO hearts and if GR signalling is required for t-system preservation in adult cardiomyocytes. Confocal and 3D STED microscopy of myocardium from cardiomyocyte-specific GRKO mice revealed decreased t-system density and increased distances between ryanodine receptors (RyR) and L-type Ca2+ channels (LTCC). Because t-system remodelling and heart failure are intertwined, we investigated the underlying mechanisms in vitro. Ventricular cardiomyocytes from failing human and healthy adult rat hearts cultured in the absence of glucocorticoids (CTRL) showed distinctively lower t-system density than cells treated with dexamethasone (EC50 1.1 nM) or corticosterone. The GR antagonist mifepristone abrogated the effect of dexamethasone. Dexamethasone improved RyR-LTCC coupling and synchrony of intracellular Ca2+ release, but did not alter expression levels of t-system-associated proteins junctophilin-2 (JPH2), bridging integrator-1 (BIN1) or caveolin-3 (CAV3). Rather, dexamethasone upregulated LC3B and increased autophagic flux. The broad-spectrum protein kinase inhibitor staurosporine prevented dexamethasone-induced upregulation of autophagy and t-system preservation, and autophagy inhibitors bafilomycin A and chloroquine accelerated t-system loss. Conversely, induction of autophagy by rapamycin or amino acid starvation preserved the t-system. These findings suggest that GR signalling and autophagy are critically involved in t-system preservation and remodelling in the heart.


Asunto(s)
Autofagia , Miocitos Cardíacos/metabolismo , Receptores de Glucocorticoides/metabolismo , Animales , Canales de Calcio Tipo L/metabolismo , Células Cultivadas , Dexametasona/farmacología , Femenino , Glucocorticoides/farmacología , Humanos , Ratones Noqueados , Miocitos Cardíacos/efectos de los fármacos , Ratas Wistar , Receptores de Glucocorticoides/genética , Canal Liberador de Calcio Receptor de Rianodina/metabolismo
5.
Appl Psychol Meas ; 34(2): 122-142, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-20514149

RESUMEN

Lengthy scales or testlets pose certain challenges for structural equation modeling (SEM) if all the items are included as indicators of a latent construct. Three general approaches (parceling, latent scoring, and shortening) to modeling lengthy scales in SEM were reviewed and evaluated. A hypothetical population model was simulated containing two exogenous constructs with 14 indicators each and an endogenous construct with four indicators. The simulation generated data sets with varying numbers of response options, two types of distributions, factor loadings ranging from low to high, and sample sizes ranging from small to moderate. The population model was varied to incorporate one of the following: (1) single parcels, (2) various parcels as indicators of two exogenous constructs, (3) latent scores as observed exogenous variables, and (4) four and six of individual items as indicators of two exogenous constructs. The dependent variables evaluated were biases in the covariance and partial covariance population parameters. Biases in these parameters were found to be minimal under the following conditions: (1) when parcels of indicators of five response options were used as indicators of two latent exogenous constructs; (2) when latent scores were used as observed variables at sample sizes above 100 and with indicators that were relatively less skewed in the case of dichotomous indicators; and (3) when four or six individual items with high or diverse factor loadings were used as indicators of two exogenous constructs. These findings provided guidelines for resolving the inconsistency of findings from applying various approaches to empirical data.

6.
J Fam Psychol ; 22(3): 367-76, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18540765

RESUMEN

This study explored the K. A. Dodge (1986) model of social information processing as a mediator of the association between interparental relationship conflict and subsequent offspring romantic relationship conflict in young adulthood. The authors tested 4 social information processing stages (encoding, hostile attributions, generation of aggressive responses, and positive evaluation of aggressive responses) in separate models to explore their independent effects as potential mediators. There was no evidence of mediation for encoding and attributions. However, there was evidence of significant mediation for both the response generation and response evaluation stages of the model. Results suggest that the ability of offspring to generate varied social responses and effectively evaluate the potential outcome of their responses at least partially mediates the intergenerational transmission of relationship conflict.


Asunto(s)
Agresión/psicología , Cortejo/psicología , Relaciones Intergeneracionales , Relaciones Interpersonales , Procesos Mentales , Conducta Social , Adolescente , Adulto , Anciano , Niño , Preescolar , Conflicto Psicológico , Femenino , Hostilidad , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Modelos Psicológicos , Estudios Prospectivos
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