Automatic mental simulation in native and non-native speakers.

Pictures of objects are verified faster when they match the implied orientation, shape, and color in a sentence-picture verification task, suggesting that people mentally simulate these features during language comprehension. Previous studies had an unintended correlation between match status and the required response, which may have influenced participants' responses by eliciting strategic use of this correlation. We removed this correlation by including color-matching filler trials and investigated if the color-match effect was still obtained. In both a native sample (Experiment 1) and a non-native sample (Experiment 2), we found strong evidence for a color-match advantage on median reaction time and error rates. Our results are consistent with the view that color is automatically simulated during language comprehension as predicted by the grounded cognition framework.

Murine erythroid differentiation kinetics in vivo under normal and anemic stress conditions.

Our current understanding of the kinetics and dynamics of erythroid differentiation is based almost entirely on the ex vivo expansion of cultured hematopoietic progenitor cells. In this study, we used an erythroid-specific, inducible transgenic mouse line to investigate for the first time, the in vivo erythroid differentiation kinetics under steady-state conditions. We demonstrated that bipotent premegakaroycyte/erythroid (PreMegE) progenitor cells differentiate into erythroid-committed proerythroblast/basophilic erythroblasts (ProBasoE) after 6.6 days under steady-state conditions. During this process, each differentiation phase (from PreMegE to precolony forming unit-erythroid [PreCFU-E], PreCFU-E to CFU-E, and CFU-E to ProBasoE) took ∼2 days in vivo. Upon challenge with 5-flurouracil (5-FU), which leads to the induction of stress erythropoiesis, erythroid maturation time was reduced from 6.6 to 4.7 days. Furthermore, anemia induced in 5-FU-treated mice was shown to be due not only to depleted bone marrow erythroid progenitor stores but also to a block in reticulocyte exit from the bone marrow into the circulation, which differed from the mechanism induced by acute blood loss.

Conception of Saviour Siblings: Religious Views in Malaysia.

The advancement of human reproductive technology has made it possible for parents with a child affected by a haematological disorder to select and bring into being, a prospective child who can act as a matched stem cell donor. This can be done through the use of preimplantation genetic diagnosis (PGD) coupled with human leukocyte antigen (HLA) typing (PGD-HLA typing), or HLA tying as a standalone procedure, where a healthy embryo, which is an HLA match to the existing sick sibling, is chosen for implantation. The creation of such a sibling (saviour sibling) is normally taken as a last resort when there is no related or unrelated matched donor. While the conception of a saviour sibling may serve as a reliable and realistic treatment option for the ailing child, it also poses new moral questions that challenge a religiously pluralistic society such as Malaysia. The use of PGD-HLA typing may be controversial as it involves creating a life to save a life, selection of compatible human embryos and destruction of the unselected embryos. At present, there is no legal framework regulating the conception of saviour siblings. The development of ethically sound and appropriate local laws and policies should consider the views of religious communities, especially when it involves a controversial subject such as the conception of saviour siblings. This article seeks to explore the perceptions of religious scholars and representatives of the major religions professed and practised in Malaysia, namely Islam, Buddhism, Christianity and Hinduism, through qualitative interviews.

Identification of novel γ-globin inducers among all potential erythroid druggable targets.

Human γ-globin is predominantly expressed in fetal liver erythroid cells during gestation from 2 nearly identical genes, HBG1 and HBG2, that are both perinatally silenced. Reactivation of these fetal genes in adult red blood cells can ameliorate many symptoms associated with the inherited ß-globinopathies, sickle cell disease, and Cooley anemia. Although promising genetic strategies to reactivate the γ-globin genes to treat these diseases have been explored, there are significant barriers to their effective implementation worldwide; alternatively, pharmacological induction of γ-globin synthesis could readily reach the majority of affected individuals. In this study, we generated a CRISPR knockout library that targeted all erythroid genes for which prospective or actual therapeutic compounds already exist. By probing this library for genes that repress fetal hemoglobin (HbF), we identified several novel, potentially druggable, γ-globin repressors, including VHL and PTEN. We demonstrate that deletion of VHL induces HbF through activation of the HIF1α pathway and that deletion of PTEN induces HbF through AKT pathway stimulation. Finally, we show that small-molecule inhibitors of PTEN and EZH induce HbF in both healthy and ß-thalassemic human primary erythroid cells.

Advancing Antiracism in Community-Based Research Practices in Early Childhood and Family Mental Health.

Structural racism-the ways that institutional policies, practices, and other norms operate to create and sustain race-based inequities1-has historically been foundational to the operations of academic medical centers and research institutions. Since its inception, academic medicine has depended on the exploitation of vulnerable communities to achieve medical, educational, and research goals.2 Research practices have long ignored or taken advantage of the individuals purportedly benefiting from the research, a dynamic most manifestly true for Black, Indigenous, and People of Color (BIPOC) communities in the United States. Reflecting current practices in racial justice work, we intentionally use the term "BIPOC" to highlight shared experiences within racially and ethnically minoritized communities, given the history of White supremacy in the United States. We acknowledge limitations of this term, which collapses myriad unique communities and histories into one construct. Specifically, child and adolescent psychiatry has historically been driven by Eurocentric approaches, paradigms, and methodology. These nonparticipatory dominant research practices have contributed to a lack of culturally responsive interventions for BIPOC communities, a paucity of evidence-based practices with demonstrated effectiveness within BIPOC communities, and disparities in access and quality of care.3 Mental health research involving BIPOC communities has been replete with exploitation and inequality.2.

A new murine Rpl5 (uL18) mutation provides a unique model of variably penetrant Diamond-Blackfan anemia.

Ribosome dysfunction is implicated in multiple abnormal developmental and disease states in humans. Heterozygous germline mutations in genes encoding ribosomal proteins are found in most individuals with Diamond-Blackfan anemia (DBA), whereas somatic mutations have been implicated in a variety of cancers and other disorders. Ribosomal protein-deficient animal models show variable phenotypes and penetrance, similar to human patients with DBA. In this study, we characterized a novel ENU mouse mutant (Skax23m1Jus) with growth and skeletal defects, cardiac malformations, and increased mortality. After genetic mapping and whole-exome sequencing, we identified an intronic Rpl5 mutation, which segregated with all affected mice. This mutation was associated with decreased ribosome generation, consistent with Rpl5 haploinsufficiency. Rpl5Skax23-Jus/+ animals had a profound delay in erythroid maturation and increased mortality at embryonic day (E) 12.5, which improved by E14.5. Surviving mutant animals had macrocytic anemia at birth, as well as evidence of ventricular septal defect (VSD). Surviving adult and aged mice exhibited no hematopoietic defect or VSD. We propose that this novel Rpl5Skax23-Jus/+ mutant mouse will be useful in studying the factors influencing the variable penetrance that is observed in DBA.

An erythroid-to-myeloid cell fate conversion is elicited by LSD1 inactivation.

Histone H3 lysine 4 methylation (H3K4Me) is most often associated with chromatin activation, and removing H3K4 methyl groups has been shown to be coincident with gene repression. H3K4Me demethylase KDM1a/LSD1 is a therapeutic target for multiple diseases, including for the potential treatment of ß-globinopathies (sickle cell disease and ß-thalassemia), because it is a component of γ-globin repressor complexes, and LSD1 inactivation leads to robust induction of the fetal globin genes. The effects of LSD1 inhibition in definitive erythropoiesis are not well characterized, so we examined the consequences of conditional inactivation of Lsd1 in adult red blood cells using a new Gata1creERT2 bacterial artificial chromosome transgene. Erythroid-specific loss of Lsd1 activity in mice led to a block in erythroid progenitor differentiation and to the expansion of granulocyte-monocyte progenitor-like cells, converting hematopoietic differentiation potential from an erythroid fate to a myeloid fate. The analogous phenotype was also observed in human hematopoietic stem and progenitor cells, coincident with the induction of myeloid transcription factors (eg, PU.1 and CEBPα). Finally, blocking the activity of the transcription factor PU.1 or RUNX1 at the same time as LSD1 inhibition rescued myeloid lineage conversion to an erythroid phenotype. These data show that LSD1 promotes erythropoiesis by repressing myeloid cell fate in adult erythroid progenitors and that inhibition of the myeloid-differentiation pathway reverses the lineage switch induced by LSD1 inactivation.

Conception of Saviour Siblings: Ethical Perceptions of Selected Stakeholders in Malaysia.

The conception of saviour siblings using preimplantation genetic diagnosis coupled with human leukocyte antigen (HLA) typing or HLA typing alone is controversial and receives a wide divergence of legal responses among countries around the world. The resulting child conceived through this procedure is dubbed a 'saviour sibling' as the child can potentially act as a compatible donor for an elder ailing sibling who needs a haematopoietic stem cell transplantation. At present, the acceptability of this procedure in Malaysia is ambiguous as there is no specific statute governing assisted reproductive technology, and the guideline issued by the Malaysian Medical Council does not expressly address this issue. The ethical arguments relating to the conception of saviour siblings in the current literature are mainly thought to reflect a liberal viewpoint which is predominantly Western in nature. This paper seeks to explore the perception of selected key stakeholders on the acceptability of and ethical concerns related to this procedure in the Malaysian context. The findings indicate that stakeholders generally support the conception of saviour siblings and some of their concerns echo the Western viewpoint. Interestingly, many were highly anxious about its economic implication, which is rarely discussed in the current literature on saviour siblings.

Epigenetic activities in erythroid cell gene regulation.

Interest in the role of epigenetic mechanisms in human biology has exponentially increased over the past several decades. The multitude of opposing and context-dependent chromatin-modifying enzymes/coregulator complexes is just beginning to be understood at a molecular level. This science has benefitted tremendously from studies of erythropoiesis, in which a series of ß-globin genes are in sequence turned "on" and "off," serving as a fascinating model of coordinated gene expression. We, therefore, describe here epigenetic complexes about which we know most, using erythropoiesis as the context. The biochemical insights lay the foundation for proposing and developing novel treatments for diseases of red cells and of erythropoiesis, identifying for example epigenetic enzymes that can be drugged to manipulate ß-globin locus regulation, to favor activation of unmutated fetal hemoglobin over mutated adult ß-globin genes to treat sickle cell disease and ß-thalassemias. Other potential translational applications are in redirecting hematopoietic commitment decisions, as treatment for bone marrow failure syndromes.

The Use of B-Cell Polysome Profiling to Validate Novel RPL5 (uL18) and RPL26 (uL24) Variants in Diamond-Blackfan Anemia.

Diamond-Blackfan anemia (DBA) is a rare bone marrow failure syndrome usually caused by heterozygous variants in ribosomal proteins (RP) and which leads to severe anemia. Genetic studies in DBA rely primarily on multigene panels that often result in variants of unknown significance. Our objective was to optimize polysome profiling to functionally validate new large subunit RP variants. We determined the optimal experimental conditions for B-cell polysome profiles then performed this analysis on 2 children with DBA and novel missense RPL5 (uL18) and RPL26 (uL24) variants of unknown significance. Both patients had reduced 60S and 80S fractions when compared with an unaffected parent consistent with a large ribosomal subunit defect. Polysome profiling using primary B-cells is an adjunctive tool that can assist in validation of large subunit RP variants of uncertain significance. Further studies are necessary to validate this method in patients with known DBA mutations, small RP subunit variants, and silent carriers.

What is the future of patient-reported outcomes in sickle-cell disease?

INTRODUCTION: Sickle cell disease (SCD) is a complex, chronic disease caused by abnormal polymerization of hemoglobin, which leads to severe pain episodes, fatigue, and end-organ damage. Patient reported outcomes (PROs) have emerged as a critical tool for measuring SCD disease severity and response to treatment. AREAS COVERED: Authors review the key issues involved when deciding to use a PRO in a clinical trial. We describe the most highly recommended generic and disease-specific PRO tools in SCD and discuss the challenges of incorporating them in clinical practice. EXPERT OPINION: PRO measures are essential to incorporate into SCD clinical trials either as primary or secondary outcomes. The use of PRO measures in SCD facilitates a patient-centered approach, which is likely to lead to improved outcomes. Significant challenges remain in adapting PRO tools to routine clinical use and in developing countries.

Hb Adana (HBA2 or HBA1: c.179G > A) and alpha thalassemia: Genotype-phenotype correlation.

Alpha thalassemia due to nondeletional mutations usually leads to more severe disease than that caused by deletional mutations. Devastating outcomes such as hydrops fetalis can occur with two nondeletional mutations, therefore warranting DNA-based workup for suspected carriers with subtle hematological abnormalities for family counseling purposes. We describe three cases with hemoglobin (Hb) Adana, a nondeletional alpha chain mutation, compounded with an alpha globin gene deletion resulting in thalassemia intermedia. We review the literature, draw genotype-phenotype correlations from published cases of Hb Adana, and propose that this correlation can be used by clinicians to help direct diagnostic studies and urge hematologists to thoroughly workup high-risk patients.

Pomalidomide reverses γ-globin silencing through the transcriptional reprogramming of adult hematopoietic progenitors.

Current therapeutic strategies for sickle cell anemia are aimed at reactivating fetal hemoglobin. Pomalidomide, a third-generation immunomodulatory drug, was proposed to induce fetal hemoglobin production by an unknown mechanism. Here, we report that pomalidomide induced a fetal-like erythroid differentiation program, leading to a reversion of γ-globin silencing in adult human erythroblasts. Pomalidomide acted early by transiently delaying erythropoiesis at the burst-forming unit-erythroid/colony-forming unit-erythroid transition, but without affecting terminal differentiation. Further, the transcription networks involved in γ-globin repression were selectively and differentially affected by pomalidomide including BCL11A, SOX6, IKZF1, KLF1, and LSD1. IKAROS (IKZF1), a known target of pomalidomide, was degraded by the proteasome, but was not the key effector of this program, because genetic ablation of IKZF1 did not phenocopy pomalidomide treatment. Notably, the pomalidomide-induced reprogramming was conserved in hematopoietic progenitors from individuals with sickle cell anemia. Moreover, multiple myeloma patients treated with pomalidomide demonstrated increased in vivo γ-globin levels in their erythrocytes. Together, these data reveal the molecular mechanisms by which pomalidomide reactivates fetal hemoglobin, reinforcing its potential as a treatment for patients with ß-hemoglobinopathies.

p53-Independent cell cycle and erythroid differentiation defects in murine embryonic stem cells haploinsufficient for Diamond Blackfan anemia-proteins: RPS19 versus RPL5.

Diamond Blackfan anemia (DBA) is a rare inherited bone marrow failure syndrome caused by ribosomal protein haploinsufficiency. DBA exhibits marked phenotypic variability, commonly presenting with erythroid hypoplasia, less consistently with non-erythroid features. The p53 pathway, activated by abortive ribosome assembly, is hypothesized to contribute to the erythroid failure of DBA. We studied murine embryonic stem (ES) cell lines harboring a gene trap mutation in a ribosomal protein gene, either Rps19 or Rpl5. Both mutants exhibited ribosomal protein haploinsufficiency and polysome defects. Rps19 mutant ES cells showed significant increase in p53 protein expression, however, there was no similar increase in the Rpl5 mutant cells. Embryoid body formation was diminished in both mutants but nonspecifically rescued by knockdown of p53. When embryoid bodies were further differentiated to primitive erythroid colonies, both mutants exhibited a marked reduction in colony formation, which was again nonspecifically rescued by p53 inhibition. Cell cycle analyses were normal in Rps19 mutant ES cells, but there was a significant delay in the G2/M phase in the Rpl5 mutant cells, which was unaffected by p53 knockdown. Concordantly, Rpl5 mutant ES cells had a more pronounced growth defect in liquid culture compared to the Rps19 mutant cells. We conclude that the defects in our RPS19 and RPL5 haploinsufficient mouse ES cells are not adequately explained by p53 stabilization, as p53 knockdown appears to increase the growth and differentiation potential of both parental and mutant cells. Our studies demonstrate that gene trap mouse ES cells are useful tools to study the pathogenesis of DBA.

Diminutive somatic deletions in the 5q region lead to a phenotype atypical of classical 5q- syndrome.

Classical 5q- syndrome is an acquired macrocytic anemia of the elderly. Similar to Diamond Blackfan anemia (DBA), an inherited red cell aplasia, the bone marrow is characterized by a paucity of erythroid precursors. RPS14 deletions in combination with other deletions in the region have been implicated as causative of the 5q- syndrome phenotype. We asked whether smaller, less easily detectable deletions could account for a syndrome with a modified phenotype. We employed single-nucleotide polymorphism array genotyping to identify small deletions in patients diagnosed with DBA and other anemias lacking molecular diagnoses. Diminutive mosaic deletions involving RPS14 were identified in a 5-year-old patient with nonclassical DBA and in a 17-year-old patient with myelodysplastic syndrome. Patients with nonclassical DBA and other hypoproliferative anemias may have somatically acquired 5q deletions with RPS14 haploinsufficiency not identified by fluorescence in situ hybridization or cytogenetic testing, thus refining the spectrum of disorders with 5q- deletions.

Impaired growth, hematopoietic colony formation, and ribosome maturation in human cells depleted of Shwachman-Diamond syndrome protein SBDS.

BACKGROUND: Shwachman-Diamond syndrome (SDS), associated with SBDS mutations, is characterized by pancreatic exocrine dysfunction and marrow failure. Sdo1, the yeast ortholog of SBDS, is implicated in maturation of the 60S ribosomal subunit, with delayed export of 60S-like particles from the nucleoplasm when depleted. Sdo1 is needed for release of the anti-subunit association factor Tif6 from 60S subunits, and Tif6 may not be recycled to the nucleus when Sdo1 is absent. METHODS: To clarify the role of SBDS in human ribosome function, TF-1 erythroleukemia and A549 lung carcinoma cells were transfected with vectors expressing RNAi against SBDS. RESULTS: Growth and hematopoietic colony forming potential of TF-1 knockdown cells were markedly hindered when compared to controls. To analyze the effect of SBDS on 60S subunit maturation in A549 cells, subunit localization was assessed by transfection with a vector expressing a fusion between human RPL29 and GFP: we found a higher percentage of SBDS-depleted cells with nuclear localization of 60S subunits. Polysome analysis of TF-1 knockdown cells showed a decrease in free 60S and 80S subunits. We also analyzed the levels of eIF6 (human ortholog of Tif6) following near-complete knockdown of SBDS in TF-1 cells and found an approximately 20% increase in the amount of eIF6 associated with the 60S subunit. CONCLUSIONS: We conclude that knockdown of SBDS leads to growth inhibition and defects in ribosome maturation, suggesting a role for wild-type SBDS in nuclear export of pre-60S subunits. Furthermore, knockdown of SBDS may interfere with eIF6 recycling.

Breast cancer in a case of Shwachman Diamond syndrome.

Shwachman Diamond syndrome (SDS) is a rare inherited bone marrow failure syndrome (IBMFS) characterized by neutropenia, exocrine pancreatic dysfunction, and cancer predisposition. Patients are at risk for myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML) but, unlike other IBMFS, there have been no reported cases of solid tumors. We report a novel case of a solid tumor in a patient with SDS and biallelic mutations in the Shwachman Bodian Diamond Syndrome gene (SBDS). Whether the development of breast cancer in this patient is due to SDS or an isolated case due to unknown factors requires further study.

Resolution of chronic hypoxemia in pediatric sickle cell patients after treatment with hydroxyurea.

Chronic hypoxemia is a common manifestation among patients with sickle cell anemia (SCA) who develop chronic lung disease. We report the beneficial effect of hydroxyurea on chronic hypoxemia in three pediatric patients with SCA and recurrent episodes of acute chest syndrome (ACS). All three patients improved rapidly after they were treated with hydroxyurea despite having additional risk factors for hypoxemia. A prospective trial is warranted to assess whether there is a therapeutic effect from the use of hydroxyurea in pediatric SCA patients with chronic hypoxemia.