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1.
PLoS Biol ; 20(11): e3001845, 2022 11.
Article in English | MEDLINE | ID: mdl-36327326

ABSTRACT

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19), which was rapidly declared a pandemic by the World Health Organization (WHO). Early clinical symptomatology focused mainly on respiratory illnesses. However, a variety of neurological manifestations in both adults and newborns are now well-documented. To experimentally determine whether SARS-CoV-2 could replicate in and affect human brain cells, we infected iPSC-derived human brain organoids. Here, we show that SARS-CoV-2 can productively replicate and promote death of neural cells, including cortical neurons. This phenotype was accompanied by loss of excitatory synapses in neurons. Notably, we found that the U.S. Food and Drug Administration (FDA)-approved antiviral Sofosbuvir was able to inhibit SARS-CoV-2 replication and rescued these neuronal alterations in infected brain organoids. Given the urgent need for readily available antivirals, these results provide a cellular basis supporting repurposed antivirals as a strategic treatment to alleviate neurocytological defects that may underlie COVID-19- related neurological symptoms.


Subject(s)
COVID-19 Drug Treatment , SARS-CoV-2 , Infant, Newborn , Humans , Sofosbuvir/pharmacology , Sofosbuvir/therapeutic use , Organoids , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Brain , Cell Death , Synapses
2.
Nat Commun ; 13(1): 2387, 2022 05 02.
Article in English | MEDLINE | ID: mdl-35501322

ABSTRACT

Transcription Factor 4 (TCF4) has been associated with autism, schizophrenia, and other neuropsychiatric disorders. However, how pathological TCF4 mutations affect the human neural tissue is poorly understood. Here, we derive neural progenitor cells, neurons, and brain organoids from skin fibroblasts obtained from children with Pitt-Hopkins Syndrome carrying clinically relevant mutations in TCF4. We show that neural progenitors bearing these mutations have reduced proliferation and impaired capacity to differentiate into neurons. We identify a mechanism through which TCF4 loss-of-function leads to decreased Wnt signaling and then to diminished expression of SOX genes, culminating in reduced progenitor proliferation in vitro. Moreover, we show reduced cortical neuron content and impaired electrical activity in the patient-derived organoids, phenotypes that were rescued after correction of TCF4 expression or by pharmacological modulation of Wnt signaling. This work delineates pathological mechanisms in neural cells harboring TCF4 mutations and provides a potential target for therapeutic strategies for genetic disorders associated with this gene.


Subject(s)
Intellectual Disability , Neurons , Cell Proliferation/genetics , Child , Humans , Hyperventilation/metabolism , Intellectual Disability/genetics , Neurons/metabolism , Transcription Factor 4/genetics , Transcription Factor 4/metabolism
3.
Brain ; 145(6): 1962-1977, 2022 06 30.
Article in English | MEDLINE | ID: mdl-34957478

ABSTRACT

Focal cortical dysplasia is a highly epileptogenic cortical malformation with few treatment options. Here, we generated human cortical organoids from patients with focal cortical dysplasia type II. Using this human model, we mimicked some focal cortical dysplasia hallmarks, such as impaired cell proliferation, the presence of dysmorphic neurons and balloon cells, and neuronal network hyperexcitability. Furthermore, we observed alterations in the adherens junctions zonula occludens-1 and partitioning defective 3, reduced polarization of the actin cytoskeleton, and fewer synaptic puncta. Focal cortical dysplasia cortical organoids showed downregulation of the small GTPase RHOA, a finding that was confirmed in brain tissue resected from these patients. Functionally, both spontaneous and optogenetically-evoked electrical activity revealed hyperexcitability and enhanced network connectivity in focal cortical dysplasia organoids. Taken together, our findings suggest a ventricular zone instability in tissue cohesion of neuroepithelial cells, leading to a maturational arrest of progenitors or newborn neurons, which may predispose to cellular and functional immaturity and compromise the formation of neural networks in focal cortical dysplasia.


Subject(s)
Epilepsy , Malformations of Cortical Development, Group I , Malformations of Cortical Development , Brain , Humans , Infant, Newborn , Neurons
4.
Ann Neurol ; 83(3): 623-635, 2018 03.
Article in English | MEDLINE | ID: mdl-29461643

ABSTRACT

OBJECTIVE: Focal cortical dysplasias (FCDs) are an important cause of drug-resistant epilepsy. In this work, we aimed to investigate whether abnormal gene regulation, mediated by microRNA, could be involved in FCD type II. METHODS: We used total RNA from the brain tissue of 16 patients with FCD type II and 28 controls. MicroRNA expression was initially assessed by microarray. Quantitative polymerase chain reaction, in situ hybridization, luciferase reporter assays, and deep sequencing for genes in the mTOR pathway were performed to validate and further explore our initial study. RESULTS: hsa-let-7f (p = 0.039), hsa-miR-31 (p = 0.0078), and hsa-miR34a (p = 0.021) were downregulated in FCD type II, whereas a transcription factor involved in neuronal and glial fate specification, NEUROG2 (p < 0.05), was upregulated. We also found that the RND2 gene, a NEUROG2-target, is upregulated (p < 0.001). In vitro experiments showed that hsa-miR-34a downregulates NEUROG2 by binding to its 5'-untranslated region. Moreover, we observed strong nuclear expression of NEUROG2 in balloon cells and dysmorphic neurons and found that 28.5% of our patients presented brain somatic mutations in genes of the mTOR pathway. INTERPRETATION: Our findings suggest a new molecular mechanism, in which NEUROG2 has a pivotal and central role in the pathogenesis of FCD type II. In this way, we found that the downregulation of hsa-miR-34a leads to upregulation of NEUROG2, and consequently to overexpression of the RND2 gene. These findings indicate that a faulty coupling in neuronal differentiation and migration mechanisms may explain the presence of aberrant cells and complete dyslamination in FCD type II. Ann Neurol 2018;83:623-635.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/metabolism , Epilepsy/metabolism , Focal Dermal Hypoplasia/metabolism , Malformations of Cortical Development/metabolism , Nerve Tissue Proteins/metabolism , Adolescent , Adult , Child , Child, Preschool , Drug Resistant Epilepsy/genetics , Epilepsy/drug therapy , Epilepsy/genetics , Female , Focal Dermal Hypoplasia/genetics , Humans , Infant , Male , Neurons/metabolism , TOR Serine-Threonine Kinases/metabolism , Transcription Factors/genetics , Young Adult , rho GTP-Binding Proteins/metabolism
5.
PLoS One ; 12(4): e0173060, 2017.
Article in English | MEDLINE | ID: mdl-28384161

ABSTRACT

Epilepsy is misdiagnosed in up to 25% of patients, leading to serious and long-lasting consequences. Recently, circulating microRNAs have emerged as potential biomarkers in a number of clinical scenarios. The purpose of this study was to identify and to validate circulating microRNAs that could be used as biomarkers in the diagnosis of epilepsy. Quantitative real-time PCR was used to measure plasma levels of three candidate microRNAs in two phases of study: an initial discovery phase with 14 patients with mesial temporal lobe epilepsy (MTLE), 13 with focal cortical dysplasia (FCD) and 16 controls; and a validation cohort constituted of an independent cohort of 65 patients with MTLE and 83 controls. We found hsa-miR-134 downregulated in patients with MTLE (p = 0.018) but not in patients with FCD, when compared to controls. Furthermore, hsa-miR-134 expression could be used to discriminate MTLE patients with an area under the curve (AUC) of 0.75. To further assess the robustness of hsa-miR-134 as a biomarker for MTLE, we studied an independent cohort of 65 patients with MTLE, 27 of whom MTLE patients were responsive to pharmacotherapy, and 38 patients were pharmacoresistant and 83 controls. We confirmed that hsa-miR-134 was significantly downregulated in the plasma of patients with MTLE when compared with controls (p < 0.001). In addition, hsa-miR-134 identified patients with MTLE regardless of their response to pharmacotherapy or the presence of MRI signs of hippocampal sclerosis. We revealed that decreased expression of hsa-miR-134 could be a potential non-invasive biomarker to support the diagnosis of patients with MTLE.


Subject(s)
Biomarkers/blood , Epilepsy, Temporal Lobe/blood , MicroRNAs/blood , Cohort Studies , Epilepsy, Temporal Lobe/genetics , Female , Humans , Male , Reverse Transcription
6.
J Neurol Sci ; 368: 19-24, 2016 Sep 15.
Article in English | MEDLINE | ID: mdl-27538595

ABSTRACT

INTRODUCTION: Skeletal muscle microRNAs (miRNAs) are potential candidate biomarkers for amyotrophic lateral sclerosis (ALS) that deserve further investigation. OBJECTIVES: To identify miRNAs abnormally expressed in the skeletal muscle and plasma of patients with ALS, and to correlate them with parameters of disease progression. METHODS: Expression profile of miRNAs in muscle was evaluated using an array platform. Subsequently we assessed the plasmatic expression of candidate miRNAs in a set of 39 patients/39 controls. We employed generalized estimating equations to investigate correlations with clinical data. RESULTS: We identified 11 miRNAs differentially expressed in the muscle of ALS patients; of these, miR424, miR-214 and miR-206 were validated by qPCR in muscle samples. In plasma, we found only miR-424 and miR 206 to be overexpressed. Baseline expression of miR-424 and 206 correlated with clinical deterioration over time. CONCLUSION: MiR-424 and miR-206 are potential prognostic markers for ALS.


Subject(s)
Amyotrophic Lateral Sclerosis/metabolism , MicroRNAs/metabolism , Biomarkers/metabolism , Blood Chemical Analysis , Disease Progression , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Muscle, Skeletal/metabolism , Polymerase Chain Reaction , Prognosis , Severity of Illness Index , Tissue Array Analysis
7.
Front Cell Neurosci ; 7: 172, 2013 Oct 04.
Article in English | MEDLINE | ID: mdl-24109432

ABSTRACT

Epilepsy, one of the most frequent neurological disorders, represents a group of diseases that have in common the clinical occurrence of seizures. The pathogenesis of different types of epilepsy involves many important biological pathways; some of which have been shown to be regulated by microRNAs (miRNAs). In this paper, we will critically review relevant studies regarding the role of miRNAs in epilepsy. Overall, the most common type of epilepsy in the adult population is temporal lobe epilepsy (TLE), and the form associated with mesial temporal sclerosis (MTS), called mesial TLE, is particularly relevant due to the high frequency of resistance to clinical treatment. There are several target studies, as well few genome-wide miRNA expression profiling studies reporting abnormal miRNA expression in tissue with MTS, both in patients and in animal models. Overall, these studies show a fine correlation between miRNA regulation/dysregulation and inflammation, seizure-induced neuronal death and other relevant biological pathways. Furthermore, expression of many miRNAs is dynamically regulated during neurogenesis and its dysregulation may play a role in the process of cerebral corticogenesis leading to malformations of cortical development (MCD), which represent one of the major causes of drug-resistant epilepsy. In addition, there are reports of miRNAs involved in cell proliferation, fate specification, and neuronal maturation and these processes are tightly linked to the pathogenesis of MCD. Large-scale analyzes of miRNA expression in animal models with induced status epilepticus have demonstrated changes in a selected group of miRNAs thought to be involved in the regulation of cell death, synaptic reorganization, neuroinflammation, and neural excitability. In addition, knocking-down specific miRNAs in these animals have demonstrated that this may consist in a promising therapeutic intervention.

8.
Can J Microbiol ; 56(7): 598-605, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20651859

ABSTRACT

The fungus Aspergillus niger was cultivated in culture medium with an alkaline ultramafic rock powder to evaluate the solubilization of potassium for biofertilizer production. The assays were carried out with 2 strains (CCT4355 and CCT911) in small-scale batch fermentations using 125, 500, 1000, and 2000 mL Erlenmeyer flasks, with a nominal volume of 40%, and rock powder at 0.4%, shaken at 160 r/min, incubated at 30 degrees C, and sampled every 7 days for 35 days. The amount of soluble K(+), the pH of the culture medium, and the acidity were determined. Both strains solubilized K(+) from the rock powder to the same extent (approximately 62%-70% after 35 days) in the 125 mL flasks; however, the percent solubilization decreased at higher volumetric scales. The results also indicated a difference in strain sensitivity to the increase in volumetric scales in batch fermentation. When filter-sterilized air was injected into the medium, the K(+) percent solubilization obtained after 4 days of cultivation was similar to that obtained after a 28 day period. The acid production by the fungus may be a mechanism of rock solubilization, in spite of the elevation in pH values probably caused by the increasing hydrolysis of the silicates. Both strains of A. niger are recommended for solubilizing potassium from ultramafic rocks, but it is necessary to optimize the oxygen transfer, which seemed to affect the rock solubilization at higher volumetric scales.


Subject(s)
Aspergillus niger/metabolism , Fermentation , Potassium/metabolism , Culture Media/metabolism , Potassium/chemistry , Solubility
9.
J Psychosom Obstet Gynaecol ; 22(4): 205-14, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11840574

ABSTRACT

Results concerning satisfaction with the birth experience in different trials are difficult to compare, owing to a lack of internationally used research scales. Salmon's Item List (SIL) is easy-to-handle and would therefore be very helpful for research as well as for obstetric clinic quality control. Two hundred and fifty-one patients were investigated using a German-language version of SIL (SIL-ger); the statistical evaluation was carried out by means of a principal components analysis. Principal components analysis revealed two major findings: (1) as stated by other authors the birth experience is multidimensional, each aspect influencing the others in a non-linear way; (2) in addition to Salmon's dimensions (i.e. postnatal 'fulfillment', intranatal 'physical discomfort' and intranatal 'emotional distress') another postnatal dimension labeled 'negative emotional experience' was detected. Not only are intranatal experiences multidimensional, but so too are evaluative feelings afterwards. In addition to fulfillment, as developed by Salmon, a dimension of negative emotional experience needs to be taken into account. This dimension does not correlate in a linear way with fulfillment. It is appropriate to use SIL in research. Before using it for purposes of clinical quality control, however, larger samples need to be evaluated in order to prove the stability of the factor structure.


Subject(s)
Cross-Cultural Comparison , Labor, Obstetric/psychology , Language , Patient Satisfaction , Psychological Tests/statistics & numerical data , Female , Humans , Infant, Newborn , Pregnancy , Psychometrics , Quality Assurance, Health Care
10.
Prax Kinderpsychol Kinderpsychiatr ; 48(8): 602-10, 1999 Oct.
Article in German | MEDLINE | ID: mdl-10582446

ABSTRACT

Operationalization of relations is tried out following an interpersonal circular model (SASB) using observation and description of behavior in dyadic and triadic relationship configurations. On a vertical and on a horizontal axis the amount of loving kindness versus hostile aggressivity and of independence versus control is determined. Different dyadic and triadic relationship configurations (e.g. child to mother or researcher to child) and also the emotional resonance of the investigating person will be rated according to anamnestic data, observed and videotaped sequences of interaction, play episodes or symbolic relationships in projective tests. Such ratings can be performed in a module like form and will be used not only in clinical practice but also in settings of scientific research. The minimal standard for a clinical examination consists of the evaluation of the child with his parents.


Subject(s)
Child Psychiatry/standards , Interpersonal Relations , Parent-Child Relations , Social Behavior , Adult , Child , Germany , Humans , Models, Psychological , Psychiatric Status Rating Scales/standards
11.
Int J Psychoanal ; 80 ( Pt 1): 71-89, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10216817

ABSTRACT

A study of early development beginning in pregnancy and extending to the end of the child's first year of life is presented. The aim is to understand the relational processes of early childhood by using the concepts of triadification and triangulation. A prospective longitudinal study was conducted with forty-one parents and their first-born infants. The parents subjective views about their parenthood and the unborn child were systematically analysed during pregnancy, targeting their representations of their own childhood experiences their partnership, and their relationship with their fantasised child. These dimensions were compared with the quality of dyadic and triadic parent-child interactions observed after the child was born. The pre-natally assessed level of triangulation in the parental fantasies correlated strongly with the quality of triadic interactions with the 4-month-old infant in a play situation and with the quality of dyadic interactions with the one-year-old infant in a stressful situation. The authors conclude that the child's relational development can be understood in triadic terms from the beginning, but that there is a regressive pull towards two-plus-one relationships under conditions of emotional dysregulation. Consequences for a psychoanalytic theory of early development are discussed.


Subject(s)
Child Development , Parent-Child Relations , Adult , Child Development/physiology , Female , Humans , Infant, Newborn , Male , Prospective Studies , Psychoanalytic Therapy , Surveys and Questionnaires
12.
Psychother Psychosom Med Psychol ; 46(3-4): 124-30, 1996.
Article in German | MEDLINE | ID: mdl-8657854

ABSTRACT

In an prospective longitudinal study of family development, 39 healthy couples were examined by the Giessen-Test 1-3 months before and 1 month and 1 year after the birth of their first child. The self-assessment and the assessment of the other spouse were recorded from both partners. By this procedure information relating to intrapsychic and interpersonal dynamics of the couple was obtained. It was evident, that during the transition from the preto the postnatal period the assessments at the personal as well as at the couples' level remained very stable. Our sample showed considerable differences compared to a representative couple sample. These differences decreased by the time of the third survey one year after the birth of the child. Although pregnancy and the birth of the first child seem to cause specific, but transitory changes in the parents self-images and in the dynamics of their relationship, our results support the notion of a high stability during the transition to parenthood with regard to the self-concepts of mother and father and especially to the structure of the parental dyad.


Subject(s)
Marriage/psychology , Parenting/psychology , Pregnancy/psychology , Adult , Female , Gender Identity , Humans , Infant, Newborn , Male , Personality Assessment , Postpartum Period/psychology , Self Concept
13.
Gynakol Geburtshilfliche Rundsch ; 36(3): 149-55, 1996.
Article in German | MEDLINE | ID: mdl-9172794

ABSTRACT

OBJECTIVE: In a longitudinal prospective study on 38 couples and their first child, we examined the influence of prenatally assessed psychological factors of the parents on somatic and psychic aspects of birth, the quality of the newly established parent-child relationship and the early development of the baby. METHODS: Half-standardized psychoanalytic interviews with the couple (pre- and postnatally conducted, video-recorded), the Giessen test for couples, an evaluation of the parents' birth narratives and a parent questionnaire about functional symptoms of the baby were used. RESULTS: We found a high continuity between the pre- and the postnatal measurements of the partnership and the emotional experiences of the parents. Somatic complications of the birth event were not correlated with prenatally assessed psychological factors. But there exists a highly significant correlation between the mental representations and the relationships of the parents and the emotional experiences of birth, the early relationship between the parents and their baby and manifestations of functional disorders of the newborn. CONCLUSIONS: Relevant psychological and psychosocial aspects should be included in the medical care of pregnant women. One should listen to the imaginations and expectations of the parents about the future parentship, including ambivalent feelings. The father should also be seen for psychological assessment.


Subject(s)
Object Attachment , Parent-Child Relations , Postpartum Period/psychology , Pregnancy/psychology , Female , Humans , Infant, Newborn , Longitudinal Studies , Marriage/psychology , Personality Assessment , Prognosis , Prospective Studies , Psychoanalytic Theory
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