Search

OBJECTIVE: Despite the increase in colorectal cancer (CRC) incidence among Chinese in Asia, there are no data on predictors of CRC screening uptake in this population. This study investigated how knowledge and perceptions about CRC correlated with screening behavior in Singaporean-Chinese. METHODS: A community-based cross-sectional study was carried out on Singaporean-Chinese at least 50 years old in Queenstown Estate, Singapore between 1/1/2006 and 1/2/2006. A questionnaire administered via face-to-face interviews elicited knowledge, perceptions and screening behavior of subjects. RESULTS: The response rate was 72.4%, with 514 completed responses. Expense was the commonest perceived barrier to screening (56.6% agreed), unlike for other populations. Social influence is important, with 67.5% agreeing to the statement 'I would go for CRC screening if my family wanted me to'. After excluding confounders, Chinese who had been for fecal occult blood test (FOBT) screening had higher knowledge score (p<0.001), lower perceived severity (p<0.01), were more likely to have been influenced by their family/friends to go for screening (p=0.04) and to have attended screening tests for other diseases (p<0.001). CONCLUSION: FOBT screening uptake is associated with specific areas of knowledge and perception among Singaporean-Chinese. To increase screening uptake within Chinese populations, clinicians should consider these factors in their approach to patients.Copyright © 2007 by Elsevier Inc. [ABSTRACT FROM AUTHOR]

Background: Reduced hearing in elderly people is important because it is disabling and potentially treatable. We aimed to assess the prevalence of reduced hearing in elderly people and levels of ownership of hearing aids and use.Methods: We have done a cross-sectional survey of people aged at least 75 years in 106 family practices in the UK. We obtained self-reported data on hearing difficulties for 32,656 people and gave 14,877 a whispered voice test (response rate 78%).Findings: 2537 (8%) of 32,656 participants reported a lot of difficulty hearing and 13,630 (42%) a little or a lot of difficulty. 3795 (26%) of 14877 participants who completed the whispered voice test (95% CI 23-29) failed the test, the proportion rising sharply with age. Following wax removal, 343 passed a retest, leaving 3452 (23%, 20-26) who failed the test, even after wax removal if present. 998 (46%) of 2180 people wearing a hearing aid at the time of testing failed the whispered voice test. More than half the people who failed the test did not own a hearing aid. 2200 (60%) of 3846 people who owned a hearing aid said they used it regularly. Level of use was strongly related to perceived benefit.Interpretation: Reduced hearing is common and provision of hearing aids inadequate in elderly people. Many people who own a hearing aid do not use it regularly, and even when wearing their aid many still have socially disabling levels of hearing loss. A major source of morbidity in elderly people could be alleviated by improvements in detection and management of reduced hearing. [ABSTRACT FROM AUTHOR]

Arterial endothelial cells (AECs) are the founder cells for intraembryonic haematopoiesis. Here, we report a method for the efficient generation of human haemogenic DLL4+ AECs from pluripotent stem cells (PSC). Time-series single-cell RNA-sequencing reveals the dynamic evolution of haematopoiesis and lymphopoiesis, generating cell types with counterparts present in early human embryos, including stages marked by the pre-haematopoietic stem cell genes MECOM/EVI1, MLLT3 and SPINK2. DLL4+ AECs robustly support lymphoid differentiation, without the requirement for exogenous NOTCH ligands. Using this system, we find IL7 acts as a morphogenic factor determining the fate choice between the T and innate lymphoid lineages and also plays a role in regulating the relative expression level of RAG1. Moreover, we document a developmental pathway by which human RAG1+ lymphoid precursors give rise to the natural killer cell lineage. Our study describes an efficient method for producing lymphoid progenitors, providing insights into their endothelial and haematopoietic ontogeny, and establishing a platform to investigate the development of the human blood system., (© 2024. The Author(s).)

Hematopoietic stem cells (HSCs) derived from human induced pluripotent stem cells (iPS cells) have important biomedical applications. We identified differentiation conditions that generate HSCs defined by robust long-term multilineage engraftment in immune-deficient NOD,B6.Prkdc scid Il2rg tm1Wjl/SzJ Kit W41/W41 mice. We guided differentiating iPS cells, as embryoid bodies in a defined culture medium supplemented with retinyl acetate, through HOXA-patterned mesoderm to hemogenic endothelium specified by bone morphogenetic protein 4 and vascular endothelial growth factor (VEGF). Removal of VEGF facilitated an efficient endothelial-to-hematopoietic transition, evidenced by release into the culture medium of CD34 + blood cells, which were cryopreserved. Intravenous transplantation of two million thawed CD34 + cells differentiated from four independent iPS cell lines produced multilineage bone marrow engraftment in 25-50% of immune-deficient recipient mice. These functionally defined, multipotent CD34 + hematopoietic cells, designated iPS cell-derived HSCs (iHSCs), produced levels of engraftment similar to those achieved following umbilical cord blood transplantation. Our study provides a step toward the goal of generating HSCs for clinical translation., (© 2024. The Author(s).)

The NR2F2 gene encodes the transcription factor COUP-TFII, which is upregulated in embryonic mesoderm. Heterozygous variants in NR2F2 cause a spectrum of congenital anomalies including cardiac and gonadal phenotypes. We generated heterozygous (MCRIi030-A-1) and homozygous (MCRIi030-A-2) NR2F2-knockout induced pluripotent stem cell (iPSC) lines from human fibroblasts using a one-step protocol for CRISPR/Cas9 gene-editing and episomal-based reprogramming. Both iPSC lines exhibited a normal karyotype, typical pluripotent cell morphology, pluripotency marker expression, and the capacity to differentiate into the three embryonic germ layers. These lines will allow us to explore the role of NR2F2 during development and disease., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Screening patients with patient-reported outcome measures allows identification of palliative care concerns. The Integrated Palliative Care Outcome Scale (IPOS) was developed in the United Kingdom for this purpose. Tools developed in another setting might not be readily usable locally. We previously evaluated the validity and reliability of the IPOS in our cardiology setting. However, it remains uncertain what factors would influence the subsequent implementation of IPOS for routine screening of patients with advanced heart failure in future practice., Objectives: This study aimed to identify the factors that could affect the IPOS implementation for patients with advanced heart failure., Design: This was a qualitative study conducted at the National Heart Centre Singapore., Methods: Patients with advanced heart failure who participated in our previous IPOS validation study were purposively recruited for semi-structured interviews. Healthcare workers caring for these patients and involved in the testing of the IPOS tool were also invited for interviews. The interviews were analyzed thematically and mapped to the Consolidated Framework for Implementation Research (CFIR)., Results: Our analysis identified six potential facilitators and six potential barriers to implementation across five major domains of the CFIR (intervention characteristics, inner setting, outer setting, individual characteristics, and process). Facilitators include: (i) perception of utility, (ii) perception of minimal complexity, (iii) perception of relatability, (iv) conducive culture, (v) dedicated resources, and (vi) advocates for implementation. Barriers include: (i) need for adaptation, (ii) mindsets/role strains, (iii) resource constraints, (iv) cultural concerns, (v) individual needs, and (vi) change process., Conclusion: Institutions could focus on cultivating appropriate perceptions and conducive cultures, providing dedicated resources for implementation and introducing facilitators to advocate for implementation. Adaptation of IPOS to suit workflows and individual needs, consideration of change processes, and systemic changes to alleviate cultural, resource, and staff role strains would improve IPOS uptake during actual implementation in clinical services., Trial Registration: Not applicable., Competing Interests: The authors declare that there is no conflict of interest., (© The Author(s), 2023.)

Chondrocytes and osteoblasts differentiated from induced pluripotent stem cells (iPSCs) will provide insights into skeletal development and genetic skeletal disorders and will generate cells for regenerative medicine applications. Here, we describe a method that directs iPSC-derived sclerotome to chondroprogenitors in 3D pellet culture then to articular chondrocytes or, alternatively, along the growth plate cartilage pathway to become hypertrophic chondrocytes that can transition to osteoblasts. Osteogenic organoids deposit and mineralize a collagen I extracellular matrix (ECM), mirroring in vivo endochondral bone formation. We have identified gene expression signatures at key developmental stages including chondrocyte maturation, hypertrophy, and transition to osteoblasts and show that this system can be used to model genetic cartilage and bone disorders.

Lymphoid cells encompass the adaptive immune system, including T and B cells and Natural killer T cells (NKT), and innate immune cells (ILCs), including Natural Killer (NK) cells. During adult life, these lineages are thought to derive from the differentiation of long-term hematopoietic stem cells (HSCs) residing in the bone marrow. However, during embryogenesis and fetal development, the ontogeny of lymphoid cells is both complex and multifaceted, with a large body of evidence suggesting that lymphoid lineages arise from progenitor cell populations antedating the emergence of HSCs. Recently, the application of single cell RNA-sequencing technologies and pluripotent stem cell-based developmental models has provided new insights into lymphoid ontogeny during embryogenesis. Indeed, PSC differentiation platforms have enabled de novo generation of lymphoid immune cells independently of HSCs, supporting conclusions drawn from the study of hematopoiesis in vivo. Here, we examine lymphoid development from non-HSC progenitor cells and technological advances in the differentiation of human lymphoid cells from pluripotent stem cells for clinical translation., (© 2023 The Authors. Immunological Reviews published by John Wiley & Sons Ltd.)

Background: The Integrated Palliative Care Outcome Scale (IPOS) was developed in the United Kingdom for health assessment in advanced illness., Objectives: To evaluate the validity and reliability of a culturally adapted IPOS (both patient and staff versions) for heart failure (HF)., Design/setting: We recruited HF patients and staff from a tertiary hospital in Singapore. We collected patient IPOS, New York Heart Association (NYHA) status, Edmonton Symptom Assessment System (ESAS) and Minnesota Living with Heart Failure (MLHF) scores at baseline, and patient IPOS at follow-up. Each baseline patient IPOS was matched with a staff IPOS., Measurements: Pearson correlation coefficient ( r ) between ESAS, MLHF, and patient IPOS was calculated to assess construct validity. The two-sample T -test assessed difference in patient and staff IPOS scores across NYHA status and care settings for known-group validity. Internal consistency of patient and staff IPOS was assessed using Cronbach's alpha ( α ). Intraclass correlation coefficient (ICC) was used to assess test-retest reliability of patient IPOS and inter-rater reliability between patient and staff IPOS., Results: Ninety-one patients and 12 staff participated. There was strong convergent validity of total patient IPOS with MLHF ( r  = 0.78) and ESAS ( r  = 0.81). There were statistically significant differences in total IPOS across care settings (patient-IPOS: 8.05, staff-IPOS 13.61) and NYHA (patient-IPOS: 7.52, staff-IPOS 12.71).There was high internal consistency of total patient ( α  = 0.83) and staff IPOS ( α  = 0.88) and high test-retest reliability of patient IPOS (ICC 0.81). Inter-rater reliability (ICC) ranged between 0.82 and 0.91., Conclusion: The IPOS was valid and reliable for HF patients in Singapore., Competing Interests: No competing financial interests exist., (© Shirlyn Hui-Shan Neo et al., 2022; Published by Mary Ann Liebert, Inc.)

Precursors of the adult hematopoietic system arise from the aorta-gonad-mesonephros (AGM) region shortly after the embryonic circulation is established. Here, we develop a microfluidic culture system to mimic the primitive embryonic circulation and address the hypothesis that circulatory flow and shear stress enhance embryonic blood development. Embryonic (HOXA + ) hematopoiesis was derived from human pluripotent stem cells and induced from mesoderm by small-molecule manipulation of TGF-β and WNT signaling (SB/CHIR). Microfluidic and orbital culture promoted the formation of proliferative CD34 + RUNX1C-GFP + SOX17-mCHERRY + precursor cells that were released into the artificial circulation from SOX17 + arterial-like structures. Single-cell transcriptomic analysis delineated extra-embryonic (yolk sac) and HOXA + embryonic blood differentiation pathways. SB/CHIR and circulatory flow enhance hematopoiesis by the formation of proliferative HOXA + RUNX1C + CD34 + precursor cells that differentiate into monocyte/macrophage, granulocyte, erythrocyte, and megakaryocyte progenitors., Competing Interests: Declaration of interests The laboratories of R.E.N., A.G.E., E.G.S., and E.S.N. receive research funding from CSL Ltd., (Crown Copyright © 2022. Published by Elsevier Inc. All rights reserved.)

Human macrophages are a natural host of many mycobacterium species, including Mycobacterium abscessus (M. abscessus), an emerging pathogen affecting immunocompromised and cystic fibrosis patients with few available treatments. The search for an effective treatment is hindered by the lack of a tractable in vitro intracellular infection model. Here, we established a reliable model for M. abscessus infection using human pluripotent stem cell-derived macrophages (hPSC-macrophages). hPSC differentiation permitted reproducible generation of functional macrophages that were highly susceptible to M. abscessus infection. Electron microscopy demonstrated that M. abscessus was present in the hPSC-macrophage vacuoles. RNA sequencing analysis revealed a time-dependent host cell response, with differing gene and protein expression patterns post-infection. Engineered tdTOMATO-expressing hPSC-macrophages with GFP-expressing mycobacteria enabled rapid image-based high-throughput analysis of intracellular infection and quantitative assessment of antibiotic efficacy. Our study describes the first to our knowledge hPSC-based model for M. abscessus infection, representing a novel and accessible system for studying pathogen-host interaction and drug discovery., Competing Interests: Conflicts of interest E.G.S. is member of the editorial board of Stem Cell Reports., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

The ontogeny of human haematopoietic stem cells (HSCs) is poorly defined owing to the inability to identify HSCs as they emerge and mature at different haematopoietic sites 1 . Here we created a single-cell transcriptome map of human haematopoietic tissues from the first trimester to birth and found that the HSC signature RUNX1 + HOXA9 + MLLT3 + MECOM + HLF + SPINK2 + distinguishes HSCs from progenitors throughout gestation. In addition to the aorta-gonad-mesonephros region, nascent HSCs populated the placenta and yolk sac before colonizing the liver at 6 weeks. A comparison of HSCs at different maturation stages revealed the establishment of HSC transcription factor machinery after the emergence of HSCs, whereas their surface phenotype evolved throughout development. The HSC transition to the liver marked a molecular shift evidenced by suppression of surface antigens reflecting nascent HSC identity, and acquisition of the HSC maturity markers CD133 (encoded by PROM1) and HLA-DR. HSC origin was tracked to ALDH1A1 + KCNK17 + haemogenic endothelial cells, which arose from an IL33 + ALDH1A1 + arterial endothelial subset termed pre-haemogenic endothelial cells. Using spatial transcriptomics and immunofluorescence, we visualized this process in ventrally located intra-aortic haematopoietic clusters. The in vivo map of human HSC ontogeny validated the generation of aorta-gonad-mesonephros-like definitive haematopoietic stem and progenitor cells from human pluripotent stem cells, and serves as a guide to improve their maturation to functional HSCs., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

In an effort to identify novel drugs targeting fusion-oncogene-induced acute myeloid leukemia (AML), we performed high-resolution proteomic analysis. In AML1-ETO (AE)-driven AML, we uncovered a deregulation of phospholipase C (PLC) signaling. We identified PLCgamma 1 (PLCG1) as a specific target of the AE fusion protein that is induced after AE binding to intergenic regulatory DNA elements. Genetic inactivation of PLCG1 in murine and human AML inhibited AML1-ETO dependent self-renewal programs, leukemic proliferation, and leukemia maintenance in vivo. In contrast, PLCG1 was dispensable for normal hematopoietic stem and progenitor cell function. These findings are extended to and confirmed by pharmacologic perturbation of Ca++-signaling in AML1-ETO AML cells, indicating that the PLCG1 pathway poses an important therapeutic target for AML1-ETO+ leukemic stem cells., (© 2022 by The American Society of Hematology.)

Exogenous growth factors play an important role in mediating hematopoietic differentiation of human pluripotent stem cells. We explored the role of different factors in early human blood cell production using blast colony formation in methylcellulose as a surrogate assay for yolk sac hematopoiesis. A reporter cell line that read out endothelial (SOX17 + ) and hematopoietic (RUNX1C + ) progenitors facilitated the identification of basic fibroblast growth and vascular endothelial growth factor as critical signals for the progression of mesoderm into endothelium. Bone morphogenetic protein 4 was needed for the subsequent generation of blood from hemogenic endothelium, and this was antagonized by Activin A or high concentrations of the WNT agonist CHIR-99021. Manipulations of the Hedgehog pathway or inhibition of Notch signaling reduced blast colony frequency but did not perturb cell differentiation. These data help to define distinct roles for prerequisite growth factors that commit mesoderm to hemogenic endothelium and subsequently allocate cells to blood lineages., Competing Interests: Conflict of interest disclosure The authors declare no competing financial interests., (Copyright © 2021 ISEH -- Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.)

The genetic regulatory network controlling early fate choices during human blood cell development are not well understood. We used human pluripotent stem cell reporter lines to track the development of endothelial and haematopoietic populations in an in vitro model of human yolk-sac development. We identified SOX17 - CD34 + CD43 - endothelial cells at day 2 of blast colony development, as a haemangioblast-like branch point from which SOX17 - CD34 + CD43 + blood cells and SOX17 + CD34 + CD43 - endothelium subsequently arose. Most human blood cell development was dependent on RUNX1. Deletion of RUNX1 only permitted a single wave of yolk sac-like primitive erythropoiesis, but no yolk sac myelopoiesis or aorta-gonad-mesonephros (AGM)-like haematopoiesis. Blocking GFI1 and/or GFI1B activity with a small molecule inhibitor abrogated all blood cell development, even in cell lines with an intact RUNX1 gene. Together, our data define the hierarchical requirements for RUNX1, GFI1 and/or GFI1B during early human haematopoiesis arising from a yolk sac-like SOX17-negative haemogenic endothelial intermediate., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

This protocol offers a detailed procedure for the in vitro differentiation of human pluripotent stem cells (hPSCs) to multipotent hematopoietic progenitors that arise from SOX17 + hemogenic endothelium, mimicking intra-embryonic, HOXA-positive, aorta-gonad mesonephros (AGM) hematopoiesis. The generated endothelium displays transcriptional similarities to cells sorted from human 5-week AGM, and CD45 + CD34 + RUNX1C + progenitors share an accessible chromatin profile with adult hematopoietic stem cells and multipotent progenitors. Therefore, this protocol is suitable for the mechanistic study of human multipotent progenitor development and for modeling childhood leukemias. For complete details on the use and execution of this protocol, please refer to Nafria et al. (2020)., Competing Interests: The authors declare no competing interests., (© 2020 The Author(s).)

Acute myeloid leukemia (AML) is a hematopoietic malignancy caused by recurrent mutations in genes encoding transcriptional, chromatin, and/or signaling regulators. The t(8;21) translocation generates the aberrant transcription factor RUNX1-ETO (RUNX1-RUNX1T1), which by itself is insufficient to cause disease. t(8;21) AML patients show extensive chromatin reprogramming and have acquired additional mutations. Therefore, the genomic and developmental effects directly and solely attributable to RUNX1-ETO expression are unclear. To address this, we employ a human embryonic stem cell differentiation system capable of forming definitive myeloid progenitor cells to express RUNX1-ETO in an inducible fashion. Induction of RUNX1-ETO causes extensive chromatin reprogramming by interfering with RUNX1 binding, blocks differentiation, and arrests cellular growth, whereby growth arrest is reversible following RUNX1-ETO removal. Single-cell gene expression analyses show that RUNX1-ETO induction alters the differentiation of early myeloid progenitors, but not of other progenitor types, indicating that oncoprotein-mediated transcriptional reprogramming is highly target cell specific., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)

Defining the ontogeny of the human adaptive immune system during embryogenesis has implications for understanding childhood diseases including leukaemias and autoimmune conditions. Using RAG1:GFP human pluripotent stem cell reporter lines, we examined human T-cell genesis from pluripotent-stem-cell-derived haematopoietic organoids. Under conditions favouring T-cell development, RAG1+ cells progressively upregulated a cohort of recognized T-cell-associated genes, arresting development at the CD4+CD8+ stage. Sort and re-culture experiments showed that early RAG1+ cells also possessed B-cell, myeloid and erythroid potential. Flow cytometry and single-cell-RNA-sequencing data showed that early RAG1+ cells co-expressed the endothelial/haematopoietic progenitor markers CD34, VECAD and CD90, whereas imaging studies identified RAG1+ cells within CD31+ endothelial structures that co-expressed SOX17+ or the endothelial marker CAV1. Collectively, these observations provide evidence for a wave of human T-cell development that originates directly from haemogenic endothelium via a RAG1+ intermediate with multilineage potential.

Withdrawal of the growth factor interleukin-3 (IL-3) from IL-3-dependent myeloid cells causes them to undergo Bax/Bak1-dependent apoptosis, whereas factor-deprived Bax -/- Bak1 -/- cells remain viable, but arrest and shrink. It was reported that withdrawal of IL-3 from Bax -/- Bak1 -/- cells caused decreased expression of the glucose transporter Glut1, leading to reduced glucose uptake, so that arrested cells required Atg5-dependent autophagy for long-term survival. In other cell types, a decrease in Glut1 is mediated by the thioredoxin-interacting protein (Txnip), which is induced in IL-3-dependent myeloid cells when growth factor is removed. We mutated Atg5 and Txnip by CRISPR/Cas9 and found that Atg5-dependent autophagy was not necessary for the long-term viability of cycling or arrested Bax -/- Bak1 -/- cells, and that Txnip was not required for the decrease in Glut1 expression in response to IL-3 withdrawal. Surprisingly, Atg5-deficient Bax/Bak1 double mutant cells survived for several weeks in medium supplemented with 10% fetal bovine serum (FBS), without high concentrations of added glucose or glutamine. When serum was withdrawn, the provision of an equivalent amount of glucose present in 10% FBS (~0.5 mM) was sufficient to support cell survival for more than a week, in the presence or absence of IL-3. Thus, Bax -/- Bak1 -/- myeloid cells deprived of growth factor consume extracellular glucose to maintain long-term viability, without a requirement for Atg5-dependent autophagy.

Congenital heart defects can be caused by mutations in genes that guide cardiac lineage formation. Here, we show deletion of NKX2-5, a critical component of the cardiac gene regulatory network, in human embryonic stem cells (hESCs), results in impaired cardiomyogenesis, failure to activate VCAM1 and to downregulate the progenitor marker PDGFRα. Furthermore, NKX2-5 null cardiomyocytes have abnormal physiology, with asynchronous contractions and altered action potentials. Molecular profiling and genetic rescue experiments demonstrate that the bHLH protein HEY2 is a key mediator of NKX2-5 function during human cardiomyogenesis. These findings identify HEY2 as a novel component of the NKX2-5 cardiac transcriptional network, providing tangible evidence that hESC models can decipher the complex pathways that regulate early stage human heart development. These data provide a human context for the evaluation of pathogenic mutations in congenital heart disease.

Hematopoietic stem cells (HSCs) differentiate into all cell types of the blood and can be used therapeutically to treat hematopoietic cancers and disorders. Despite decades of research, it is not yet possible to derive therapy-grade HSCs from pluripotent precursors. Analysis of HSC development in model organisms has identified some of the molecular cues that are necessary to instruct hematopoiesis in vivo, including Wnt9A, which is required during an early time window in zebrafish development. Although bona fide HSCs cannot be derived in vitro, it is possible to model human hematopoietic progenitor development by differentiating human pluripotent stem cells to hematopoietic cells. Herein, we modulate WNT9A expression during the in vitro differentiation of human embryonic stem cells to hematopoietic progenitor cells and demonstrate that WNT9A also regulates human hematopoietic progenitor cell development in vitro. Overexpression of WNT9A only impacts differentiation to CD34⁺/CD45⁺ cells during early time windows and does so in a dose-dependent manner. The cells that receive the Wnt signal-not the cells that secrete WNT9A-differentiate most efficiently to hematopoietic progenitors; this mimics the paracrine action of Wnt9a during in vivo hematopoiesis. Taken together, these data indicate that WNT9A is a conserved regulator of zebrafish and human hematopoietic development., Competing Interests: The authors declare no conflict of interest.

Delayed foot wound healing is a major complication attributed to hyperglycemia in type 2 diabetes mellitus (DM) patients, and these wounds may develop into foot ulcers. There are at least two types of DM wound models used in rodents to study delayed wound healing. However, clinically relevant animal models are not common. Most models use type 1 DM rodents or wounds created on the back rather than on the foot. An open full-thickness excision wound on the footpad of type 2 DM rats is more clinically relevant, but such a model has not yet been characterized systematically. The objective of this study was to investigate and characterize how DM affected a full-thickness excision open foot wound in n5-streptozotocin (n5-STZ)-induced type 2 DM rats. We hypothesized that elevated inflammation, reduced blood circulation, and cell proliferation due to hyperglycemia could delay the wound healing of DM rats. The wounds of DM rats were compared with those of non-DM rats (Ctrl) at Days 1 and 8 post wounding. The wound healing process of the DM rats was significantly delayed compared with that of the Ctrl rats. The DM rats also had higher C-reactive protein (CRP) and lower blood circulation and proliferating cell nuclear antigen (PCNA) in DM wounds. This confirmed that elevated inflammation and reduced blood flow and cell proliferation delayed foot wound healing in the n5-STZ rats. Hence, this open foot wound animal model provides a good approach to study the process of delayed wound healing.

Haematopoietic stem cells (HSCs) emerge during embryogenesis and give rise to the adult haematopoietic system. Understanding how early haematopoietic development occurs is of fundamental importance for basic biology and medical sciences, but our knowledge is still limited compared with what we know of adult HSCs and their microenvironment. This is particularly true for human haematopoiesis, and is reflected in our current inability to recapitulate the development of HSCs from pluripotent stem cells in vitro In this Review, we discuss what is known of human haematopoietic development: the anatomical sites at which it occurs, the different temporal waves of haematopoiesis, the emergence of the first HSCs and the signalling landscape of the haematopoietic niche. We also discuss the extent to which in vitro differentiation of human pluripotent stem cells recapitulates bona fide human developmental haematopoiesis, and outline some future directions in the field., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2017. Published by The Company of Biologists Ltd.)

Introduction: Maternal mental health has been largely neglected in the literature. Women, however, may be vulnerable to developing post-traumatic stress symptoms or post-traumatic stress disorder (PTSD), following traumatic birth. In turn, this may affect their capacity for child rearing and ability to form a secure bond with their baby and impact on the wider family. Trauma-focused psychological therapies (TFPT) are widely regarded as effective and acceptable interventions for PTSD in general and clinical populations. Relatively little is known about the effectiveness of TFPT for women postpartum who have post-traumatic stress symptoms., Methods and Analysis: We will conduct a review to assess the effectiveness of TFPT, compared with usual postpartum care, as a treatment for post-traumatic stress symptoms or PTSD for women following traumatic birth. Using a priori search criteria, we will search for randomised controlled trials (RCT) in four databases: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO and OpenGrey. We will use search terms that relate to the population, TFPT and comparators. Screening of search results and data extraction will be undertaken by two reviewers, independently. Risk of bias will be assessed in RCTs which meet the review criteria. Data will be analysed using the following methods, as appropriate: narrative synthesis; meta-analysis; subgroup analysis and meta-regression., Dissemination and Ethics: As this work comprises a synthesis of existing studies, ethical approvals are not required. Results will be disseminated at conferences and in publications., Competing Interests: Conflicts of Interest: None declared., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

The ability to generate hematopoietic stem cells from human pluripotent cells would enable many biomedical applications. We find that hematopoietic CD34 + cells in spin embryoid bodies derived from human embryonic stem cells (hESCs) lack HOXA expression compared with repopulation-competent human cord blood CD34 + cells, indicating incorrect mesoderm patterning. Using reporter hESC lines to track the endothelial (SOX17) to hematopoietic (RUNX1C) transition that occurs in development, we show that simultaneous modulation of WNT and ACTIVIN signaling yields CD34 + hematopoietic cells with HOXA expression that more closely resembles that of cord blood. The cultures generate a network of aorta-like SOX17 + vessels from which RUNX1C + blood cells emerge, similar to hematopoiesis in the aorta-gonad-mesonephros (AGM). Nascent CD34 + hematopoietic cells and corresponding cells sorted from human AGM show similar expression of cell surface receptors, signaling molecules and transcription factors. Our findings provide an approach to mimic in vitro a key early stage in human hematopoiesis for the generation of AGM-derived hematopoietic lineages from hESCs.

Multilevel models provide a flexible modelling framework for cost-effectiveness analyses that use cluster randomised trial data. However, there is a lack of guidance on how to choose the most appropriate multilevel models. This paper illustrates an approach for deciding what level of model complexity is warranted; in particular how best to accommodate complex variance-covariance structures, right-skewed costs and missing data. Our proposed models differ according to whether or not they allow individual-level variances and correlations to differ across treatment arms or clusters and by the assumed cost distribution (Normal, Gamma, Inverse Gaussian). The models are fitted by Markov chain Monte Carlo methods. Our approach to model choice is based on four main criteria: the characteristics of the data, model pre-specification informed by the previous literature, diagnostic plots and assessment of model appropriateness. This is illustrated by re-analysing a previous cost-effectiveness analysis that uses data from a cluster randomised trial. We find that the most useful criterion for model choice was the deviance information criterion, which distinguishes amongst models with alternative variance-covariance structures, as well as between those with different cost distributions. This strategy for model choice can help cost-effectiveness analyses provide reliable inferences for policy-making when using cluster trials, including those with missing data., (© The Author(s) 2013.)

Aim: This paper seeks to identify gaps within nursing collective agreements for opportunities to implement practices to sustain the nursing workforce., Background: Since the majority of nurses in Canada are unionised, some of the strategies recommended in the literature to cope with nursing shortage may not apply to unionised nurses, making collective agreements a potential source for designing practices that can mitigate the impact of ageing nurses., Method: Nine major collective agreements for registered nurses in each province governing the nursing employment relationship were analysed to see if different practices were already addressed in the collective agreements., Results: Five such practices were identified, including: providing more mentorship opportunities; encouraging nurses who are eligible to retire to remain in the nursing workforce; attracting internationally trained nurses; implementing operational changes that include process improvements or new technologies; and empowering nurses through flexibility in work schedules., Conclusion: If collective agreements are silent in any of the strategies identified in the literature, health-care organisations can adopt these practices without violating the collective agreements., Implications for Nursing Management: Non-unionised health-care organisations can also benefit from learning about these policies and practices to assist in managing and sustaining an ageing nursing workforce., (© 2016 John Wiley & Sons Ltd.)