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Abstract Transcription factor GATA1 controls the delicate balance between proliferation, differentiation and apoptosis in both the erythroid and megakaryocytic lineages. In addition to full-length GATA1, there is an GATA1 isoform, GATA1s, that lacks the amino-terminal transactivation domain. Somatic GATA1 mutations that lead to the exclusive production of GATA1s appear to be necessary and sufficient for the development of a preleukemic condition called transient myeloproliferative disorder (TMD) in Down syndrome newborns. Subsequent clonal evolution among latent TMD blasts leads to the development of acute megakaryoblastic leukemia (AMKL). We originally established transgenic mice that express only GATA1s, which exhibit hyperproliferation of immature megakaryocytes, thus mimicking human TMD; however, these mice never developed AMKL. Here, we report that transgenic mice expressing moderate levels of GATA1s, i.e., roughly comparable levels to endogenous GATA1, were prone to develop AMKL in young adults. However, when GATA1s is expressed at levels significantly exceeding that of endogenous GATA1, the development of leukemia was restrained in a dose dependent manner. If the transgenic increase of GATA1s in progenitors remains small, GATA1s supports the terminal maturation of megakaryocyte progenitors insufficiently, and consequently the progenitors persisted, leading to an increased probability for acquisition of additional genetic modifications. In contrast, more abundant GATA1s expression compensates for this maturation block, enabling megakaryocytic progenitors to fully differentiate. This study provides evidence for the clinical observation that the abundance of GATA1s correlates well with the progression to AMKL in Down syndrome.

Abstract GATA1 plays a critical role in differentiation, proliferation, and apoptosis during erythropoiesis. We developed a Gata1 knock-down allele (Gata1.05) that results in GATA1 expression at 5% of endogenous level. In female mice heterozygous for both the Gata1.05 and wild-type alleles, we observed a predisposition to erythroblastic leukemia three to six months after birth. Since no male Gata1.05 progeny survive gestation, we originally maintained heterozygous females in a mixed genetic background of C57BL/6J and DBA/2 strains. Around 30% of these mice reproducibly develop leukemia, but the other subset did not develop leukemia, even though they harbor a high number of preleukemic erythroblasts. These observations prompted us to hypothesize that there may be potential influence of genetic determinants on the progression of Gata1.05-driven hematopoietic precursors to full-blown leukemia. In an initial examination of Gata1.05/X mice backcrossed into C3H/He, BALB/c, DBA/2, C57BL/6J and 129X1/SvJ strains, we discerned that the backgrounds of C57BL/6J and 129X1/SvJ significantly expedited leukemia onset in Gata1.05/X mice. Conversely, backgrounds of C3H/He, BALB/c and DBA/2 did not substantially modify the effect of the Gata1 mutation. This indicates the existence of genetic modifiers that accentuate Gata1.05 leukemogenesis. Subsequent cohort studies evaluated Gata1.05/X mice within mix backgrounds of BALB/c:129X1/SvJ and BALB/c:C57BL/6J. In these settings, Gata1.05-driven leukemia manifested in autosomal dominant patterns within the 129X1/SvJ background and in autosomal recessive patterns within C57BL/6J background. To the best of our knowledge, this study provides the inaugural evidence of genetic modifiers that can reshape the outcome based on leukemia-associated gene signatures.

Objective To evaluate co-prescribing of sedatives hypnotics and opioids.Design Retrospective study evaluating the association of patient characteristics and comorbidities with coprescribing.Setting and participants Using the national Merative MarketScan Database between 2005 and 2018, we identified patients who received an incident sedative prescription with or without subsequent, incident opioid prescriptions within a year of the sedative prescription in the USA.Outcome measures Coprescription of sedative-hypnotics and opioids.Results A total of 2 632 622 patients (mean (SD) age, 43.2 (12.34) years; 1 297 356 (62.5%) female) received incident prescriptions for sedatives over the course of the study period. The largest proportion of sedative prescribing included benzodiazepines (71.1%); however, z-drugs (19.9%) and barbiturates (9%) were also common. About 557 845 (21.2%) patients with incident sedatives also received incident opioid prescriptions. About 59.2% of these coprescribed patients received opioids coprescription on the same day. Multivariate logistic regression findings showed that individuals with a comorbidity index score of 1, 2 or ≥3 (aOR 1.19 (95% CI 1.17 to 1.21), 1.17 (95% C 1.14 to 1.19) and 1.25 (95% C 1.2 to 1.31)) and substance use disorder (1.21 (95% C 1.19 to 1.23)) were more likely to be coprescribed opioids and sedatives. The likelihood of receiving both opioid and sedative prescriptions was lower for female patients (aOR 0.93; 95% CI 0.92 to 0.94), and those receiving a barbiturate (aOR 0.3; 95% CI 0.29 to 0.31) or z-drugs (aOR 0.67; 95% CI 0.66 to 0.68) prescriptions at the index date.Conclusions Coprescription of sedatives with opioids was associated with the presence of comorbidities and substance use disorder, gender and types of sedatives prescribed at the index date. Additionally, more than half of the coprescribing occurred on the same day which warrants further evaluation of current prescribing and dispensing best practice guidelines.

: Objectives: To study COVID?19 (Delta Variant) cases and close contacts co?located within households. Focusing on epidemiology of transmission of COVID?19, quarantine duration and utilisation of infection control behaviours under a telehealth model of care in an elimination setting. Methods: A retrospective cohort analysis examined household spread of infection, duration of quarantine and change in PCR CT value during illness. A survey explored infection control behaviours used by household members during isolation and quarantine. Results: The cohort was 141 individuals in 35 households. Thirty?seven were index cases, and 48 became positive during quarantine, most within 10 days. Whole?household infection occurred in 12 households with multiple members. Behaviours focused on fomite transmission reduction rather than preventing aerosol transmission. The median duration of close contact household quarantine was 25 days. The majority of COVID?19 cases were de?isolated after 14 days with no evidence of further community transmission. Conclusion: Intrahousehold transmission was not universal and, if it occurred, usually occurred quickly. Behaviours utilised focused on fomites, suggesting a need for improved education regarding the potential utilisation of strategies to prevention the transmission of aerosols. Households experienced long durations of home?based quarantine. Implications for public health: The impact of long quarantine durations must be considered, particularly where most community benefit from quarantine is achieved within 10 days from exposure in the setting of the Delta Variant. Education of households regarding aerosol risk reduction is a potential strategy in the household setting of individuals at risk of disease progression., The incursion of SARS?CoV?2 into the Australian community from returning travellers and subsequent community transmission has required a significant public health response since the commencement of the pandemic. In the [...]

Abstract Ribosomal protein dysfunction causes diverse human diseases, including Diamond–Blackfan anemia (DBA). Despite the universal need for ribosomes in all cell types, the mechanisms underlying ribosomopathies, which are characterized by tissue-specific defects, are still poorly understood. In the present study, we analyzed the transcriptomes of single purified erythroid progenitors isolated from the bone marrow of DBA patients. These patients were categorized into untreated, glucocorticoid (GC)-responsive and GC-non-responsive groups. We found that erythroid progenitors from untreated DBA patients entered S-phase of the cell cycle under considerable duress, resulting in replication stress and the activation of P53 signaling. In contrast, cell cycle progression was inhibited through induction of the type 1 interferon pathway in treated, GC-responsive patients, but not in GC-non-responsive patients. Notably, a low dose of interferon alpha treatment stimulated the production of erythrocytes derived from DBA patients. By linking the innately shorter cell cycle of erythroid progenitors to DBA pathogenesis, we demonstrated that interferon-mediated cell cycle control underlies the clinical efficacy of glucocorticoids. Our study suggests that interferon administration may constitute a new alternative therapeutic strategy for the treatment of DBA. The trial was registered at www.chictr.org.cn as ChiCTR2000038510.

Abstract Background Hypoxia is a hallmark of the tumor microenvironment (TME) and in addition to altering metabolism in cancer cells, it transforms tumor-associated stromal cells. Within the tumor stromal cell compartment, tumor-associated macrophages (TAMs) provide potent pro-tumoral support. However, TAMs can also be harnessed to destroy tumor cells by monoclonal antibody (mAb) immunotherapy, through antibody dependent cellular phagocytosis (ADCP). This is mediated via antibody-binding activating Fc gamma receptors (FcγR) and impaired by the single inhibitory FcγR, FcγRIIb. Methods We applied a multi-OMIC approach coupled with in vitro functional assays and murine tumor models to assess the effects of hypoxia inducible factor (HIF) activation on mAb mediated depletion of human and murine cancer cells. For mechanistic assessments, siRNA-mediated gene silencing, Western blotting and chromatin immune precipitation were utilized to assess the impact of identified regulators on FCGR2B gene transcription. Results We report that TAMs are FcγRIIbbright relative to healthy tissue counterparts and under hypoxic conditions, mononuclear phagocytes markedly upregulate FcγRIIb. This enhanced FcγRIIb expression is transcriptionally driven through HIFs and Activator protein 1 (AP-1). Importantly, this phenotype reduces the ability of macrophages to eliminate anti-CD20 monoclonal antibody (mAb) opsonized human chronic lymphocytic leukemia cells in vitro and EL4 lymphoma cells in vivo in human FcγRIIb+/+ transgenic mice. Furthermore, post-HIF activation, mAb mediated blockade of FcγRIIb can partially restore phagocytic function in human monocytes. Conclusion Our findings provide a detailed molecular and cellular basis for hypoxia driven resistance to antitumor mAb immunotherapy, unveiling a hitherto unexplored aspect of the TME. These findings provide a mechanistic rationale for the modulation of FcγRIIb expression or its blockade as a promising strategy to enhance approved and novel mAb immunotherapies.

The objective was to characterize the pharmacokinetics (PK) and pharmacodynamics (PD) of glucagon after injectable or nasal administration and confirm the appropriate therapeutic dose of nasal glucagon (NG) for adult patients. Six clinical studies with PK and five clinical studies with PD (glucose) data were included in the analysis. Doses ranging from 0.5 to 6 mg NG, and 0.5 to 1 mg injectable glucagon were studied. A total of 6284 glucagon and 7130 glucose concentrations from 265 individuals (patients and healthy participants) were available. Population PK/PD modeling was performed using NONMEM. Glucagon exposure and glucose response were simulated for patients administered various doses of NG to confirm the optimal dose. Glucagon PK was well‐described with a single compartment disposition with first‐order absorption and elimination processes. Bioavailability of NG relative to injectable glucagon was 16%. Exposure–response modeling revealed that lower baseline glucose was associated with higher maximum drug effect. The carry‐over effect from prior insulin administration was incorporated into the model through a time‐dependent increase in elimination rate of glucose. Simulations showed that more than 99% of hypoglycemic adult patients would experience treatment success, defined as an increase in blood glucose to ≥70 mg/dL or an increase of ≥20 mg/dL from nadir within 30 min after administration of NG 3 mg. The population PK/PD model adequately described the PK and PD profiles of glucagon after nasal administration. Modeling and simulations confirmed that NG 3 mg is the most appropriate dose for rescue treatment during hypoglycemia emergencies. [ABSTRACT FROM AUTHOR]

Innovative game-based training methods that leverage the ubiquity of cellphones and familiarity with phone-based interfaces have the potential to transform the training of public health practitioners in low-income countries such as Liberia. This article describes the design, development, and testing of a prototype of the Figure It Out mobile game. The prototype game uses a disease outbreak scenario to promote evidence-based decision-making in determining the causative agent and prescribing intervention measures to minimize epidemiological and logistical burdens in resource-limited settings. An initial prototype of the game developed by the US team was playtested and evaluated by focus groups with 20 University of Liberia Masters of Public Health (UL MPH) students. Results demonstrate that the learning objectives—improving search skills for identifying scientific evidence and considering evidence before decision-making during a public health emergency—were considered relevant and important in a setting that has repeatedly and recently experienced severe threats to public health. However, some of the game mechanics that were thought to enhance engagement such as trial-and-error and choose-your-own-path gameplay, were perceived by the target audience as distracting or too time-consuming, particularly in the context of a realistic emergency scenario. Gameplay metrics that mimicked real-world situations around lives lost, money spent, and time constraints during public health outbreaks were identified as relatable and necessary considerations. Our findings reflect cultural differences between the game development team and end users that have emphasized the need for end users to have an integral part of the design team; this formative evaluation has critically informed next steps in the iterative development process. Our multidisciplinary, cross-cultural and cross-national design team will be guided by Liberia-based public health students and faculty, as well as community members who represent our end user population in terms of experience and needs. These stakeholders will make key decisions regarding game objectives and mechanics, to be vetted and implemented by game design experts, epidemiologists, and software developers.

In 2013, China launched its ‘Belt and Road Initiative’ (BRI) as a major effort to enhance international trade and economic development. An important feature of the BRI is that it supports free trade regimes and a world economy based upon open regional cooperation. The concept of BRI involves establishing a transport route between China and participating countries to provide more profitable trade and investment corridors. There are few comprehensive studies examining the social and environmental impact on development in recipient countries. To address this gap, this study gathered empirical evidence on railroad projects in three key countries: Indonesia, Ethiopia, and Kenya. The comparative analysis revealed that while political leaders signed agreements that welcomed China’s BRI in support of their national transport development plans, the implementation of these ambitious infrastructure projects faced significant management and operational challenges that had not been foreseen by the Chinese partners. More effective implementation of BRI infrastructure projects in the future will require better understandings of governance, specifically through harmonization with the cultural, institutional and political contexts in partner countries. Social and cultural characteristics of the countries where Chinese firms are working need to be well understood if sustainable and inclusive benefits from the BRI infrastructure projects are to be delivered. Further research on the benefits gained by local people living in the areas affected by the BRI investments is needed.

Deep venous thrombosis (DVT) and secondary pulmonary embolism cause approximately 100,000 deaths per year in the United States. Physical immobility is the most significant risk factor for DVT, but a molecular and cellular basis for this link has not been defined. We found that the endothelial cells surrounding the venous valve, where DVTs originate, express high levels of FOXC2 and PROX1, transcription factors known to be activated by oscillatory shear stress. The perivalvular venous endothelial cells exhibited a powerful antithrombotic phenotype characterized by low levels of the prothrombotic proteins vWF, P-selectin, and ICAM1 and high levels of the antithrombotic proteins thrombomodulin (THBD), endothelial protein C receptor (EPCR), and tissue factor pathway inhibitor (TFPI). The perivalvular antithrombotic phenotype was lost following genetic deletion of FOXC2 or femoral artery ligation to reduce venous flow in mice, and at the site of origin of human DVT associated with fatal pulmonary embolism. Oscillatory blood flow was detected at perivalvular sites in human veins following muscular activity, but not in the immobile state or after activation of an intermittent compression device designed to prevent DVT. These findings support a mechanism of DVT pathogenesis in which loss of muscular activity results in loss of oscillatory shear-dependent transcriptional and antithrombotic phenotypes in perivalvular venous endothelial cells, and suggest that prevention of DVT and pulmonary embolism may be improved by mechanical devices specifically designed to restore perivalvular oscillatory flow., Introduction Deep venous thrombosis (DVT) is a common vascular disease with an annual incidence of 0.1% among the general population, and more than 1% among hospitalized individuals (1). Pulmonary embolism--the [...]

Summary: Infectious diseases continually pose global medical challenges. The transcription factor GATA2 establishes gene networks and defines cellular identity in hematopoietic stem/progenitor cells and in progeny committed to specific lineages. GATA2-haploinsufficient patients exhibit a spectrum of immunodeficiencies associated with bacterial, viral, and fungal infections. Despite accumulating clinical knowledge of the consequences of GATA2 haploinsufficiency in humans, it is unclear how GATA2 haploinsufficiency compromises host anti-infectious defenses. To address this issue, we examined Gata2-heterozygous mutant (G2Het) mice as a model for human GATA2 haploinsufficiency. In vivo inflammation imaging and cytokine multiplex analysis demonstrated that G2Het mice had attenuated inflammatory responses with reduced levels of inflammatory cytokines, particularly IFN-γ, IL-12p40, and IL-17A, during lipopolysaccharide-induced acute inflammation. Consequently, bacterial clearance was significantly impaired in G2Het mice after cecal ligation and puncture-induced polymicrobial peritonitis. These results provide direct molecular insights into GATA2-directed host defenses and the pathogenic mechanisms underlying observed immunodeficiencies in GATA2-haploinsufficient patients.

Synthetic bone models such as polyurethane (PU) foam are a well-established substitute to cadaveric bone for screw pull-out testing; however, little attention has been given to the effect of PU foam anisotropy on orthopaedic implant testing. Compressive and screw pull-out performance in three PU foam densities; 0.16 g/cm3 (PCF 10), 0.32 g/cm3 (PCF 20) and 0.64 g/cm3 (PCF 40) were performed in each of the X, Y or Z orientations. The maximum compressive force, stiffness in the linear region, maximum stress and modulus were determined for all compression tests. Pedicle screws were inserted and pulled out axially to determine maximum pull-out force, energy to failure and stiffness. One-way ANOVA and post hoc tests were used to compare outcome variables between PU foam densities and orientations, respectively. Compression tests demonstrated the maximum force was significantly different between all orientations for PCF 20 (X, Y and Z) while stiffness and maximum stress were different between X versus Y and X versus Z. Maximum pull-out force was significantly different between all orientations for PCF 10 foam. No significant differences were noted for other foam densities. There is potential for screw pull-out testing results to be significantly affected by orientation in lower density PU foams. It is recommended that a single, known orientation of the PU foam block be used for experimental testing. [ABSTRACT FROM AUTHOR]

Abstract Background Muscle-invasive bladder cancer (MIBC) is a heterogeneous disease, and gene expression profiling has identified several molecular subtypes with distinct biological and clinicopathological characteristics. While MIBC subtyping has primarily been based on messenger RNA (mRNA), long non-coding RNAs (lncRNAs) may provide additional resolution. Methods LncRNA expression was quantified from microarray data of a MIBC cohort treated with neoadjuvant chemotherapy (NAC) and radical cystectomy (RC) (n = 223). Unsupervised consensus clustering of highly variant lncRNAs identified a four-cluster solution, which was characterized using a panel of MIBC biomarkers, regulon activity profiles, gene signatures, and survival analysis. The four-cluster solution was confirmed in The Cancer Genome Atlas (TCGA) cohort (n = 405). A single-sample genomic classifier (GC) was trained using ridge-penalized logistic regression and validated in two independent cohorts (n = 255 and n = 94). Results NAC and TCGA cohorts both contained an lncRNA cluster (LC3) with favorable prognosis that was enriched with tumors of the luminal-papillary (LP) subtype. In both cohorts, patients with LP tumors in LC3 (LPL-C3) were younger and had organ-confined, node-negative disease. The LPL-C3 tumors had enhanced FGFR3, SHH, and wild-type p53 pathway activity. In the TCGA cohort, LPL-C3 tumors were enriched for FGFR3 mutations and depleted for TP53 and RB1 mutations. A GC trained to identify these LPL-C3 patients showed robust performance in two validation cohorts. Conclusions Using lncRNA expression profiles, we identified a biologically distinct subgroup of luminal-papillary MIBC with a favorable prognosis. These data suggest that lncRNAs provide additional information for higher-resolution subtyping, potentially improving precision patient management.

Insomnia and obstructive sleep apnoea (OSA) frequently co-occur and may be causally related through sleep fragmentation and/or hyperarousal mechanisms. Previous studies suggest that OSA treatment can improve insomnia severity. However, the effect of insomnia treatment on OSA severity has not been investigated. We performed a randomised controlled trial to investigate the effect of cognitive behavioural therapy for insomnia (CBTi) on OSA severity, controlling for potential sleep-stage and posture effects. 145 patients with comorbid insomnia (International Classification of Sleep Disorders, 3rd Edn) and untreated OSA (apnoea–hypopnoea index (AHI) ≥15 events·h−1 sleep) were randomised to a four-session CBTi programme or to a no-treatment control. Overnight sleep studies were completed pre- and post-treatment to measure AHI, arousal index and sleep architecture, to investigate the effect of intervention group, time, sleep stage (N1–3 or REM) and posture (supine or nonsupine) on OSA severity. The CBTi group showed a 7.5 event·h−1 greater AHI difference (mean (95% CI) decrease 5.5 (1.3–9.7) events·h−1, Cohen's d=0.2, from 36.4 events·h−1 pre-treatment) across sleep-stages and postures, compared to control (mean increase 2.0 (−2.0–6.1) events·h−1, d=0.01, from 37.5 events·h−1 at pre-treatment; interaction p=0.012). Compared to control, the CBTi group also had a greater reduction in total number (mean difference 5.6 (0.6–10.6) greater overall reduction; p=0.029) and duration of nocturnal awakenings (mean difference 21.1 (2.0–40.3) min greater reduction; p=0.031) but showed no difference in the arousal index, or sleep architecture. CBTi consolidates sleep periods and promotes a 15% decrease in OSA severity in patients with comorbid insomnia and OSA. This suggests that insomnia disorder may exacerbate OSA and provides further support for treating insomnia in the presence of comorbid OSA.

The aim of this study was to develop and refine a heterologous mouse model of endometriosis-associated pain in which non-evoked responses, more relevant to the patient experience, were evaluated. Immunodeficient female mice (N = 24) were each implanted with four endometriotic human lesions (N = 12) or control tissue fat (N = 12) on the abdominal wall using tissue glue. Evoked pain responses were measured biweekly using von Frey filaments. Non-evoked responses were recorded weekly for 8 weeks using a home cage analysis (HCA). Endpoints were distance traveled, social proximity, time spent in the center vs. outer areas of the cage, drinking, and climbing. Significant differences between groups for von Frey response, climbing, and drinking were detected on days 14, 21, and 35 post implanting surgery, respectively, and sustained for the duration of the experiment. In conclusion, a heterologous mouse model of endometriosis-associated evoked a non-evoked pain was developed to improve the relevance of preclinical models to patient experience as a platform for drug testing.

LncRNAs modulate diverse physiological cellular processes, however, their involvement in heme-dependent processes are not yet clear. Here the authors reveal the role of lncRNA UCA1 in erythroid cell development.

Transcription factor GATA1 controls the delicate balance between proliferation, differentiation and apoptosis in both the erythroid and megakaryocytic lineages. In addition to full-length GATA1, there is an GATA1 isoform, GATA1s, that lacks the amino-terminal transactivation domain. Somatic GATA1 mutations that lead to the exclusive production of GATA1s appear to be necessary and sufficient for the development of a preleukemic condition called transient myeloproliferative disorder (TMD) in Down syndrome newborns. Subsequent clonal evolution among latent TMD blasts leads to the development of acute megakaryoblastic leukemia (AMKL). We originally established transgenic mice that express only GATA1s, which exhibit hyperproliferation of immature megakaryocytes, thus mimicking human TMD; however, these mice never developed AMKL. Here, we report that transgenic mice expressing moderate levels of GATA1s, i.e., roughly comparable levels to endogenous GATA1, were prone to develop AMKL in young adults. However, when GATA1s is expressed at levels significantly exceeding that of endogenous GATA1, the development of leukemia was restrained in a dose dependent manner. If the transgenic increase of GATA1s in progenitors remains small, GATA1s supports the terminal maturation of megakaryocyte progenitors insufficiently, and consequently the progenitors persisted, leading to an increased probability for acquisition of additional genetic modifications. In contrast, more abundant GATA1s expression compensates for this maturation block, enabling megakaryocytic progenitors to fully differentiate. This study provides evidence for the clinical observation that the abundance of GATA1s correlates well with the progression to AMKL in Down syndrome. Key points: 1. The abundance of GATA1s is a strong prognostic factor of TMD for leukemia by mediating differentiation of megakaryocytes. 2. Persistent TMD blasts not undergoing differentiation are prone to leukemic transformation. [ABSTRACT FROM AUTHOR]