127 research outputs found

    Targeting mitochondria to stimulate hematopoiesis.

    Get PDF

    Differential Blood Counts Do Not Consistently Predict Clinical Measurements of Bone Mineral Density and Microarchitecture at Homeostasis.

    Get PDF
    The hematopoietic stem cell niche constitutes a complex bone marrow (BM) microenvironment. Osteoporosis is characterized by both reduced bone mineral density (BMD) and microarchitectural deterioration, constituting the most frequent alteration of the BM microenvironment. It is unclear to which extent modifications of the BM microenvironment, including in the context of osteoporosis, influence blood cell production. We aimed to describe the association between lumbar spine and total hip BMD and microarchitecture (assessed by trabecular bone score [TBS]) and differential blood counts. Data were collected at two time points from 803 (first assessment) and 901 (second assessment) postmenopausal women participating in the CoLaus/OsteoLaus cohort, a population-based sample in Lausanne, Switzerland. Participants with other active disease or treatment that could influence hematopoiesis or osteoporosis were excluded. Bivariate and multivariate associations between each peripheral blood cell count and BMD or TBS were performed. Additionally, participants in the highest BMD and TBS tertiles were compared with participants in the lowest BMD and TBS tertiles. At first assessment, only neutrophils were significantly different in the lowest BMD and TBS tertile (3.18 ± 0.09 versus 3.47 ± 0.08 G/L, p = 0.028). At the second assessment, leucocytes (5.90 ± 0.11 versus 5.56 ± 0.10 G/L, p = 0.033), lymphocytes (1.87 ± 0.04 versus 1.72 ± 0.04 G/L p = 0.033), and monocytes (0.49 ± 0.01 versus 0.46 ± 0.1 G/L, p = 0.033) were significantly different. Power analysis did not identify quasi-significant associations missed due to sample size. Although significant associations between blood counts and BMD or TBS were found, none was consistent across bone measurements or assessments. This study suggests that, at homeostasis and in postmenopausal women, there is no clinically significant association between the osteoporotic microenvironment and blood production output as measured by differential blood counts. In the context of conflicting reports on the relationship between osteoporosis and hematopoiesis, our study represents the first prospective two time-point analysis of a large, homogenous cohort at steady state. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research

    Correlation study between osteoporosis and hematopoiesis in the context of adjuvant chemotherapy for breast cancer.

    Get PDF
    This retrospective study attempts to establish if a correlation exists between osteoporosis and hematopoiesis before and after adjuvant chemotherapy in the context of non-metastatic breast cancer. Osteoporosis is interpreted both as a direct marker of osteoblastic decline and as an indirect marker of increased bone marrow adiposity within the hematopoietic microenvironment. Patients from the "Centre du Sein" at CHUV (Centre Hospitalier Universitaire Vaudois) undergoing adjuvant chemotherapy were included in this study. Evolution of blood counts was studied in correlation with the osteoporosis status. Toxicity of chemotherapy was coded according to published probability of febrile neutropenia. One hundred forty-three women were included: mean age 52.1 ± 12.5 years, mean BMI (body mass index) 24.4 ± 4.1. BMD (bone mineral density) scored osteoporotic in 32% and osteopenic in 45%. Prior to chemotherapy, BMD was positively correlated with neutrophil (p < 0.001) and thrombocyte (p = 0.01) count; TBS (trabecular bone score) was not correlated with blood count. After the first cycle of chemotherapy, an increase of one point in TBS correlated with a decrease of 57% on the time to reach leucocyte nadir (p = 0.004). There was a positive correlation between BMD and risk of infection (p < 0.001). Our data demonstrates an association between osteoporosis and lower blood counts in a younger cohort than previously published, extending it for the first time to neutrophil counts in females. Our results suggest that the healthier the bone, the earlier the lowest leucocyte count value, prompting further research on this area

    High-throughput, nonperturbing quantification of lipid droplets with digital holographic microscopy.

    Get PDF
    In vitro differentiating adipocytes are sensitive to liquid manipulations and have the tendency to float. Assessing adipocyte differentiation using current microscopy techniques involves cell staining and washing, while using flow cytometry involves cell retrieval in suspension. These methods induce biases, are difficult to reproduce, and involve tedious optimizations. In this study, we present digital holographic microscopy (DHM) as a label-free, nonperturbing means to quantify lipid droplets in differentiating adipocytes in a robust medium- to high-throughput manner. Taking advantage of the high refractive index of lipid droplets, DHM can assess the production of intracellular lipid droplets by differences in phase shift in a quantitative manner. Adipocytic differentiation, combined with other morphological features including cell confluence and cell death, was tracked over 6 days in live OP9 mesenchymal stromal cells. We compared DHM with other currently available methods of lipid droplet quantification and demonstrated its robustness with modulators of adipocytic differentiation in a dose-responsive manner. This study suggests DHM as a novel marker-free nonperturbing method to study lipid droplet accumulation and may be envisioned for drug screens and mechanistic studies on adipocytic differentiation

    MarrowQuant Across Aging and Aplasia: A Digital Pathology Workflow for Quantification of Bone Marrow Compartments in Histological Sections.

    Get PDF
    The bone marrow (BM) exists heterogeneously as hematopoietic/red or adipocytic/yellow marrow depending on skeletal location, age, and physiological condition. Mouse models and patients undergoing radio/chemotherapy or suffering acute BM failure endure rapid adipocytic conversion of the marrow microenvironment, the so-called "red-to-yellow" transition. Following hematopoietic recovery, such as upon BM transplantation, a "yellow-to-red" transition occurs and functional hematopoiesis is restored. Gold Standards to estimate BM cellular composition are pathologists' assessment of hematopoietic cellularity in hematoxylin and eosin (H&E) stained histological sections as well as volumetric measurements of marrow adiposity with contrast-enhanced micro-computerized tomography (CE-μCT) upon osmium-tetroxide lipid staining. Due to user-dependent variables, reproducibility in longitudinal studies is a challenge for both methods. Here we report the development of a semi-automated image analysis plug-in, MarrowQuant, which employs the open-source software QuPath, to systematically quantify multiple bone components in H&E sections in an unbiased manner. MarrowQuant discerns and quantifies the areas occupied by bone, adipocyte ghosts, hematopoietic cells, and the interstitial/microvascular compartment. A separate feature, AdipoQuant, fragments adipocyte ghosts in H&E-stained sections of extramedullary adipose tissue to render adipocyte area and size distribution. Quantification of BM hematopoietic cellularity with MarrowQuant lies within the range of scoring by four independent pathologists, while quantification of the total adipocyte area in whole bone sections compares with volumetric measurements. Employing our tool, we were able to develop a standardized map of BM hematopoietic cellularity and adiposity in mid-sections of murine C57BL/6 bones in homeostatic conditions, including quantification of the highly predictable red-to-yellow transitions in the proximal section of the caudal tail and in the proximal-to-distal tibia. Additionally, we present a comparative skeletal map induced by lethal irradiation, with longitudinal quantification of the "red-to-yellow-to-red" transition over 2 months in C57BL/6 femurs and tibiae. We find that, following BM transplantation, BM adiposity inversely correlates with kinetics of hematopoietic recovery and that a proximal to distal gradient is conserved. Analysis of in vivo recovery through magnetic resonance imaging (MRI) reveals comparable kinetics. On human trephine biopsies MarrowQuant successfully recognizes the BM compartments, opening avenues for its application in experimental, or clinical contexts that require standardized human BM evaluation

    O enfoque qualitativo na avaliação de programas psicoeducativos: Aplicações e contributos da metodologia qualitativa

    Get PDF
    Os programas psicoeducativos surgem, nas mais diversas áreas, como uma oportunidade de desenvolvimento pessoal, verificando-se uma demanda crescente de propostas baseadas na evidência. Na avaliação destes programas assiste-se porém a alguma insatisfação com a metodologia quantitativa, sobretudo, quando não permite perceber profundamente os processos de mudança. O objetivo deste trabalho é ilustrar o contributo da metodologia qualitativa à investigação desenvolvida, através da apresentação de três processos distintos: a) entrevista semiestruturada (construída a partir da abordagem fenomenológica e utilizada como avaliação pré-teste, pós-teste e follow-up num programa de educação parental); b) metodologia observacional (útil para avaliação formativa de programas e análise do processo de mudança de comportamentos ao longo dos programas); e c) Q-set da Resiliência Familiar (método misto, originalmente construído para a avaliação do funcionamento resiliente das famílias em risco psicossocial). Apresentam-se os resultados alcançados em estudos realizados e discute-se a pertinência da sua aplicação no âmbito da avaliação da intervenção psicoeducativa.Psychoeducational programmes appear, in several areas, as an opportunity for personal development, and there is a growing demand for evidence-based interventions. Yet, in its evaluation framework has been recognized some dissatisfaction with the quantitative methodology, especially when it does not contribute to deeply understand the processes of change. The objective of this paper is to illustrate the contribution of qualitative methodology to research, presenting three different processes: a) semi-structured interview (it was built considering the phenomenological approach and was used for a pre-test, post-test and follow-up assessment in a parenting educational programme); observational method (useful for training programmes assessment and analysis of the process of behavior change occurred over the programmes); and c) Q-set of family resilience (mixed method, originally built for the evaluation of the resilient functioning of psychosocial risk families). We present the results obtained and we discusses the relevance of its application in the assessment of psychoeducational intervention.info:eu-repo/semantics/publishedVersio

    EVIDENCE-BASED PSYCHOEDUCATIONAL INTERVENTION: THE CONTRIBUTION OF QUALITATIVE APPROACHES

    Get PDF
    Neste trabalho pretende-se discutir o contributo da metodologia qualitativa na avaliação da eficácia dos processos de mudança quando se implementam programas psicoeducativos. Concretamente apresentam-se três recursos distintos: a) entrevista semiestruturada (construída a partir da abordagem fenomenológica e utilizada como avaliação pré-teste, pós-teste e follow-up num programa de educação parental); b) metodologia observacional (útil para avaliação formativa de programas e análise do processo de mudança de comportamentos ao longo dos programas); e c) Q-set da Resiliência Familiar (método misto, originalmente construído para a avaliação do funcionamento resiliente das famílias em risco psicossocial). Cada um dos recursos é discutido, ilustrando-se a sua utilização e a pertinência da sua aplicação no âmbito da avaliação da eficácia da intervenção psicoeducativa.The main goal of this paper is to discuss the contribution of qualitative methodology for the assessment of the changing processes due to psychoeducational intervention. Three different resources are presented: a) semi-structured interview (it was built considering the phenomenological approach and was used for a pre-test, post-test and follow-up assessment in a parenting educational programme); observational method (useful for training programmes assessment and analysis of the process of behavior change occurred over the programmes); and c) Q-set of family resilience (mixed method, originally built for the evaluation of the resilient functioning of psychosocial risk families). These resources are discussed and is stated the relevance of their aplication in the assessment of psychoeducational intervention.info:eu-repo/semantics/publishedVersio
    corecore