Midbrain dopaminergic neuron fate specification of pluripotent stem cells

Disorders of dopaminergic neurons in the midbrain are associated with various brain diseases such as Parkinson’s disease (PD), for which there are no effective treatments. Pluripotent stem cells (PSCs) offer a remarkable potential for finding new therapeutic strategies because they are self-renewable and capable to differentiate into all cell types. However, biomedical applications of PSCs require knowledge of the molecular mechanisms directing PSCs into midbrain dopaminergic (mDA) cell fate. During development the generation of mDA neurons is induced by the extrinsic molecules SHH, FGF8 and WNT1 in the caudal region of the Otx2 positive domain, which marks the presumptive fore- and midbrain, and rostrally to the future hindbrain expressing Gbx2. In this study I have further investigated the role of FGF signalling in the generation of mDA neurons. Here, I have used mouse epiblast stem cells (EpiSCs). Based on their developmentally primed pluripotent state, we assumed that they represent a more suitable system when compared with mouse embryonic stem cells. I validated neural differentiation of EpiSCs as an alternative model to study neural development in vitro. I found that inhibition of the FGF/ERK activity at the onset of EpiSC differentiation initiated expression of Wnt and Shh and further induced ventral midbrain progenitor markers, accompanied by suppressing caudalisation as well as forebrain induction. To maintain ventral midbrain progenitor fate, cells required a period of endogeneous FGF/ERK signalling. Subsequent treatment of FGF8 and SHH, which restricts progenitors from adopting alternative fates, led to highly efficient production of authentic mDA neurons. These neurons exhibited functional, neuron-like properties and when implanted into the striatum of mouse PD model strongly restored parkinsonian features without any signs of overgrowth. In conclusion, a temporally controlled modulation of FGF/ERK activity during neural differentiation from PSCs is crucial for reliable and highly efficient generation of functional authentic mDA neurons

Rmst Is a Novel Marker for the Mouse Ventral Mesencephalic Floor Plate and the Anterior Dorsal Midline Cells

The availability of specific markers expressed in different regions of the developing nervous system provides a useful tool to illuminate their development, regulation and function. We have identified by expression profiling a putative non-coding RNA, Rmst, that exhibits prominent expression in the midbrain floor plate region, the isthmus and the roof plate of the anterior neural tube. At the developmental stage when the ventral dopaminergic neuron territory is being established, Rmst expression appears to be restricted to the presumptive dopaminergic neurons of the ventral tegmental area that lies close to the ventral midline. Thus this study presents Rmst as a novel marker for the developing dopaminergic neurons in the mesencephalic floor plate as well as a marker for the dorsal midline cells of the anterior neural tube and the isthmic organizer

Dopaminergic Progenitors Derived From Epiblast Stem Cells Function Similarly to Primary VM-Derived Progenitors When Transplanted Into a Parkinson’s Disease Model

Neural transplantation in neurodegenerative diseases such as Parkinson’s disease (PD) offers to replace cells lost during the progression of the disease process. Primary fetal ventral mesencephalon (VM), the origin of bona fide midbrain dopaminergic (DAergic) precursors, is currently the gold standard source of cells for transplantation in PD. However, the use of tissue from this source raises ethical and logistical constraints necessitating the need for alternative supplies of donor cells. The requirement of any alternative donor cell source is to have the capability to generate authentic mature DAergic neurons, which could be utilized in cell-replacement strategies. Mouse pluripotent stem cells can efficiently generate electrochemically mature midbrain DAergic precursors in vitro using a stepwise control of FGF signaling. Here, we have compared DAergic transplants derived from two progenitor cell sources in an allograft system: mouse epiblast stem cells (EpiSC) and primary fetal mouse VM tissue. Cells were transplanted into the striatum of 6-OHDA lesioned mice pre-treated with L-DOPA. Drug-induced rotations, a number of motor tests and drug-induced abnormal involuntary movements (AIMs) were assessed. Functional improvements were demonstrated post-transplantation in some behavioral tests, with no difference in graft volume or the number of TH immuno-positive cells in the grafts of the two transplant groups. L-DOPA-induced AIMs and amphetamine-induced AIMs were observed in both transplant groups, with no differences in rate or severity between the two groups. Collectively, in this mouse-to-mouse allograft system, we report no significant differences in the functional ability between the gold standard primary VM derived and pluripotent stem cell-derived DAergic transplants

НАЩАДКИ КОШОВОГО ОТАМАНА ЙОСИПА ГЛАДКОГО

Постать останнього кошового отамана Задунайської запорозької Січі а згодом й Азовського козацького війська Йосипа Михайловича Гладкого не залишилася поза увагою істориків [1] і народної пам’яті [2]. Діяльність цієї, безумовно, харизматичної людини отримала неоднозначну оцінку в попередній і сучасній історіографії. Останнім часом з’явилися ґрунтовні дослідження запорозького історика Людмили Маленко, присвячені історії Азовського козацького війська [3] і персонально діяльності отамана цього війська Й.Гладкого [4]. Дослідниця ввела до наукового обігу потужний корпус нових джерел. У полі зору Л.Маленко опинилася також і генеалогія Гладких. Проте ще наприкінці 1880-х рр. цього питання торкався відомий дослідник Запорожжя Дмитро Іванович Яворницький (1855-1940). Він був чи не першим, хто більш-менш повно висвітлив родинні стосунки Й.Гладкого. Вже у першій своїй великій монографії “Запорожжя в залишках старовини і переказах народу” Д.Яворницький приділив немало рядків Й.Гладкому та його нащадкам [5]. Головним джерелом у цьому дослідженні були документи родинного архіву Гладких. Яворницькому допомагав в цьому питанні його олександрівський приятель і відомий дослідник історії й фольклору місцевого краю Яків Павлович Новицький (1847-1925). В творчому доробку історика є й спеціальна стаття, присвячена Й. Гладкому та його генеалогії [6]

The Self-Assessment Scale of Cognitive Complaints in Schizophrenia: A validation study in Tunisian population

<p>Abstract</p> <p>Background</p> <p>Despite a huge well-documented literature on cognitive deficits in schizophrenia, little is known about the own perception of patients regarding their cognitive functioning. The purpose of our study was to create a scale to collect subjective cognitive complaints of patients suffering from schizophrenia with Tunisian Arabic dialect as mother tongue and to proceed to a validation study of this scale.</p> <p>Methods</p> <p>The authors constructed the Self-Assessment Scale of Cognitive Complaints in Schizophrenia (SASCCS) based on a questionnaire covering five cognitive domains which are the most frequently reported in the literature to be impaired in schizophrenia. The scale consisted of 21 likert-type questions dealing with memory, attention, executive functions, language and praxia. In a second time, the authors proceeded to the study of psychometric qualities of the scale among 105 patients suffering from schizophrenia spectrum disorders (based on DSM- IV criteria). Patients were evaluated using the Positive and Negative Syndrome Scale (PANSS), the Global Assessment Functioning Scale (GAF scale) and the Calgary Depression Scale (CDS).</p> <p>Results</p> <p>The scale's reliability was proven to be good through Cronbach alpha coefficient equal to 0.85 and showing its good internal consistency. The intra-class correlation coefficient at 11 weeks was equal to 0.77 suggesting a good stability over time. Principal component analysis with Oblimin rotation was performed and yielded to six factors accounting for 58.28% of the total variance of the scale.</p> <p>Conclusion</p> <p>Given the good psychometric properties that have been revealed in this study, the SASCCS seems to be reliable to measure schizophrenic patients' perception of their own cognitive impairment. This kind of evaluation can't substitute for objective measures of cognitive performances in schizophrenia. The purpose of such an evaluation is to permit to the patient to express his own well-being and satisfaction of quality of life.</p

Hierarchical folding and reorganization of chromosomes are linked to transcriptional changes in cellular differentiation

Mammalian chromosomes fold into arrays of megabase‐sized topologically associating domains (TADs), which are arranged into compartments spanning multiple megabases of genomic DNA. TADs have internal substructures that are often cell type specific, but their higher‐order organization remains elusive. Here, we investigate TAD higher‐order interactions with Hi‐C through neuronal differentiation and show that they form a hierarchy of domains‐within‐domains (metaTADs) extending across genomic scales up to the range of entire chromosomes. We find that TAD interactions are well captured by tree‐like, hierarchical structures irrespective of cell type. metaTAD tree structures correlate with genetic, epigenomic and expression features, and structural tree rearrangements during differentiation are linked to transcriptional state changes. Using polymer modelling, we demonstrate that hierarchical folding promotes efficient chromatin packaging without the loss of contact specificity, highlighting a role far beyond the simple need for packing efficiency

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure &lt; 100 mmHg (n = 1127), estimated glomerular filtration rate &lt; 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

“I think to myself ‘why now?’” – a qualitative study about endometriosis and pain in Austria

Abstract Background Endometriosis is a chronic, benign, and oestrogen-dependent condition and about 10–15% of all women of reproductive age are affected by endometriosis worldwide. It is not curable and pain is one of the most common symptoms of endometriosis and leads to low quality of life in affected women. To our knowledge, in German-speaking countries, no studies with qualitative methods approaches are available concerning women who suffer from pain caused by endometriosis and possible associated coping strategies. Our study aims to familiarise ourselves with the individual pain experience of selected women who suffer from endometriosis in Austria and their coping strategies. Methods A qualitative study design was based on problem-centred interviews for data collection and qualitative content analysis for data analysis. The research participants were women aged between 18 and 55 diagnosed with endometriosis and living in Austria. The interview period was from 27 February to 26 March 2019 and interviews lasted between 50 and 75 min. Results Eight categories were formulated, of which category 3 (thoughts and feelings regarding endometriosis and pain - ‘why?’), category 5 (effects and changes caused by endometriosis and pain – ‘quality of life’), category 7 (taboos – ‘don`t talk about it’), and category 8 (talking about it – ‘contact with others in the same position’) were relevant for this article. The remaining four categories [1–4] have already been published elsewhere. Conclusion Our data show that the social environment plays a fundamental role in coping strategies concerning pain caused by endometriosis. Women in our study reported that exchange with peers offers support. This opens a door for information events, patient organizations like support groups, and the inclusion of these in the supporting system. Involving occupational medicine and workplace health promotion departments in companies should be further goals to support affected women