Understanding the role of mother guilt and self-compassion in health behaviors in mothers with young children.

We explored whether the guilt mothers of young children feel about engaging in health behaviors mediates the relationship between self-compassion and self-reported engagement in health-promoting behaviors such as physical activity, eating a healthy diet and getting enough sleep. In this online, cross-sectional study, 143 mothers of young children completed measures of self-compassion, guilt about taking time to engage in health-promoting behaviors, trait guilt, health-promoting behaviors, self-esteem, and demographics. Mediation analysis, using Hayes' PROCESS macro showed that mother guilt mediated the relationship between self-compassion and health-promoting behaviors, ß = .

Colony forming cell assays for human hematopoietic progenitor cells.

Hematopoietic stem cells (HSCs) present in small numbers in adult bone marrow (BM), peripheral blood (PB) and umbilical cord blood (CB) produce a heterogeneous pool of progenitors that can be detected in vitro using colony forming cell (CFC) assays. Hematopoietic progenitor cells proliferate and differentiate to produce colonies of maturing cells when cultured in a semisolid methylcellulose-based medium that is supplemented with suitable growth factors and other supplements. The colonies are then classified and enumerated in situ by light microscopy or an automated imaging instrument.

Long-term culture-initiating cell assay for mouse cells.

The long-term culture-initiating cell (LTC-IC) assay is a well-established in vitro assay used to enumerate primitive mouse hematopoietic stem cells (HSCs) and relies on the two cardinal functions of HSCs: ability to self-renew and differentiation capacity. LTC-ICs present in minimally processed and purified cell suspensions and cocultured on a supportive feeder layer are detected by their sustained ability to produce hematopoietic progenitors (colony forming cells) after ≥ 4 weeks in culture. Refinements including the use of a defined stromal cell line, and extending the in vitro culture to 6 weeks allow detection of LTC-IC at similar frequencies to transplantable HSCs quantified using in vivo assays.

Human long-term culture initiating cell assay.

The long-term culture initiating cell (LTC-IC) assay, founded on the bone marrow long-term culture (LTC) system, measures primitive hematopoietic stem cells (termed LTC-IC) based on their capacity to produce myeloid progeny for at least 5 weeks. Adaptations of the LTC system including the use of stromal cell lines, application of limiting dilution analysis, and estimation of average hematopoietic progenitor output per LTC-IC under defined conditions have made it possible to accurately determine LTC-IC content in minimally separated and highly purified cell populations from human hematopoietic tissue sources such as bone marrow, peripheral blood, cord blood, fetal liver as well as cord blood and mobilized peripheral blood. Methodologies for measuring human LTC-IC using bulk cultures, limiting dilution analysis, and single cell cultures are described.

Characterization of mouse hematopoietic stem and progenitor cells.

The unit describes functional assays for the quantification of mouse hematopoietic stem cells and progenitor cells. The competitive repopulating unit (CRU) assay detects transplantable mouse hematopoietic stem cells with the capacity to regenerate all of the blood cell lineages for extended time periods in vivo. The long-term culture-initiating cell (LTC-IC) assay, founded on the bone marrow long-term culture system, measures primitive hematopoietic progenitors based on their capacity to produce myeloid progeny for at least four weeks.

Human and mouse hematopoietic colony-forming cell assays.

Hematopoietic stem cells present in small numbers in certain fetal organs during development and in adult bone marrow produce a heterogeneous pool of progenitors that can be detected in vitro using colony-forming cell (CFC) assays. Hematopoietic progenitor cells, when cultured in a semisolid methylcellulose-based medium that is supplemented with suitable growth factors, proliferate and differentiate to produce clonal clusters (colonies) of maturing cells. The CFCs are then classified and enumerated in situ by light microscopy.

The marrow homing efficiency of murine hematopoietic stem cells remains constant during ontogeny.

Objective: Several recent studies have established the potential clinical utility of hematopoietic stem cells (HSCs) not only for marrow rescue but also for regenerating diseased or damaged nonhematopoietic tissues. These findings have focused renewed interest in understanding the in vivo trafficking patterns of HSCs from different sources. Previous experiments have suggested that the half-life of HSCs in the circulation is short, although the actual proportion that return to the bone marrow (BM) following transplantation has not been previously quantitated.

Common and distinct features of cytokine effects on hematopoietic stem and progenitor cells revealed by dose-response surface analysis.

Recent studies have identified thrombopoietin (TPO), flt-3 ligand (FL), Steel factor (SF), and interleukin-11 (IL-11) as cytokines able to stimulate amplification of the most primitive murine hematopoietic cells in vitro. However, dose-response and interaction parameters that predict how to optimize mixtures of these cytokines have not been previously defined. To obtain this information, Sca-1(+)lin(-) and c-kit(+)Sca-1(+)lin(-) adult mouse bone marrow cells were cultured for 10 and 14 days, respectively, in serum-free medium with varying concentrations of these cytokines.

Feasibility of using autologous transplantation to evaluate hematopoietic stem cell-based gene therapy strategies in transgenic mouse models of human disease.

Histoincompatibility between murine donors and recipients of bone marrow (BM) transplants reduces engraftment, and this compromises assessment of hematopoietic stem cells (HSCs) in certain transgenic mice. To study HSCs in the S+S-Antilles mouse model of human sickle cell disease (SCD), we developed an autotransplant protocol. Initial experiments showed no differences between S+S-Antilles mice and normal C57BL/6 (+/+) mice in their radiosensitivity or baseline hematopoietic progenitor numbers.

Ex vivo expansion of human and murine hematopoietic stem cells.

The last decade has seen major advances in our knowledge of the molecular control of hematopoiesis, widespread access to cytokines, and the development of practical assays for quantitating highly primitive hematopoietic cells. This progress has now made feasible the predictable manipulation of hematopoietic stem cells (HSC) and progenitors for a variety of experimental and clinical applications. Nevertheless, our understanding of events that induce and/ or block the differentiation of primitive hematopoietic cells is still very limited.

Quantitation of murine and human hematopoietic stem cells by limiting-dilution analysis in competitively repopulated hosts.

In designing functional assays for the various classes of hematopoietic cells described in this book, one needs to consider the properties of the cell to be measured which must be incorporated into the assay design, and the end points to allow its specific detection. The most primitive hematopoietic stem cells (HSC) in mouse and man are characterized by two cardinal properties that distinguish them from more mature clonogenic cells and their terminally differentiated progeny. Firstly, HSCs are pluripotent: they are characterized by the potential to differentiate into all of the eight major lineages of lymphoid, myeloid, and erythroid cells in vivo (1-3).

Long-term culture-initiating cell assays for human and murine cells.

In normal adults, the majority of primitive hematopoietic cells are concentrated in the bone marrow, where they are in contact with a variety of molecules that influence their cell-cycle status, viability, motility, and differentiation. These include components of the extracellular matrix, soluble and bound growth-promoting factors and inhibitors, and adhesion molecules that mediate direct interactions between cells. The long-term culture (LTC) system initially developed to support the continued production of myeloid cells, (1-3) and subsequently for the production of lymphoid cells (4-7) has provided a unique approach for the investigation of the regulation and maintenance of early hematopoietic progenitors under conditions that reproduce many aspects of the marrow microenvironment.