Nuclear matrix proteins distinguish normal diploid osteoblasts from osteosarcoma cells

Interrelationships between nuclear architecture and gene expression were examined by comparing the representation of nuclear matrix proteins in ROS 17/2.8 rat and MG-63 human osteosarcoma cells with those in normal diploid osteoblasts. The tumor-derived cells coexpress genes which are expressed in a sequential and mutually exclusive manner during the progressive stages of osteoblast differentiation. In osteosarcoma cells two-dimensional electrophoretic analysis indicates a composite representation of nuclear matrix proteins characteristic of both the proliferative and postproliferative periods of osteoblast phenotype development. In addition, nuclear matrix proteins unique to the tumor cells and the absence of nuclear matrix proteins found only in normal diploid osteoblasts are observed. Tumor-specific nuclear matrix proteins include those expressed in a proliferation-dependent and independent manner. There is a parallel relationship between nuclear matrix proteins and the expression of cell growth and tissue-specific genes during osteoblast differentiation and in osteosarcoma cells where the developmental sequence of gene expression has been abrogated. Nuclear matrix proteins therefore provide markers reflecting defined periods of bone cell differentiation and phenotypic characteristics of an osteosarcoma

Loss of Nmp4 optimizes osteogenic metabolism and secretion to enhance bone quality

A goal of osteoporosis therapy is to restore lost bone with structurally sound tissue. Mice lacking the transcription factor Nuclear Matrix Protein 4 (Nmp4, Zfp384, Ciz, ZNF384) respond to several classes of osteoporosis drugs with enhanced bone formation compared to wild type (WT) animals. Nmp4-/- mesenchymal stem/progenitor cells (MSPCs) exhibit an accelerated and enhanced mineralization during osteoblast differentiation. To address the mechanisms underlying this hyper-anabolic phenotype, we carried out RNA-sequencing and molecular and cellular analyses of WT and Nmp4-/- MSPCs during osteogenesis to define pathways and mechanisms associated with elevated matrix production. We determined that Nmp4 has a broad impact on the transcriptome during osteogenic differentiation, contributing to the expression of over 5,000 genes. Phenotypic anchoring of transcriptional data was performed for the hypothesis-testing arm through analysis of cell metabolism, protein synthesis and secretion, and bone material properties. Mechanistic studies confirmed that Nmp4-/- MSPCs exhibited an enhanced capacity for glycolytic conversion- a key step in bone anabolism. Nmp4-/- cells showed elevated collagen translation and secretion. Expression of matrix genes that contribute to bone material-level mechanical properties were elevated in Nmp4-/- cells, an observation that was supported by biomechanical testing of bone samples from Nmp4-/- and WT mice. We conclude that loss of Nmp4 increases the magnitude of glycolysis upon the metabolic switch, which fuels the conversion of the osteoblast into a super-secretor of matrix resulting in more bone with improvements in intrinsic quality

Megakaryocytes Enhance Mesenchymal Stromal Cells Proliferation and Inhibit Differentiation

Megakaryocytes (MKs) can induce proliferation of calvarial osteoblasts [Ciovacco et al., 2009], but this same phenomenon has not been reported for bone marrow stromal populations from long bones. Bone marrow contains several types of progenitor cells which can be induced to differentiate into multiple cell types. Herein, we examined mesenchymal stromal cell proliferation and osteoblastic differentiation when rabbit or mouse MK were cultured with i) rabbit bone marrow stromal cells, ii) rabbit dental pulp stromal cells, or iii) mouse bone marrow stromal cells. Our results demonstrated that rabbit and mouse stromal cells co-cultured with rabbit MK or mouse MK, have significant increases in proliferation on day 7 by 52%, 46%, and 24%, respectively, compared to cultures without MK. Conversely, alkaline phosphatase (ALP) activity was lower at various time points in these cells when cultures contain MK. Similarly, calcium deposition observed at day 14 rabbit bone marrow and dental pulp stromal cells and day 21 mouse bone marrow stromal cells was 63%, 69%, and 30% lower respectively, when co-cultured with MK. Gene expression studies reveal transcriptional changes broadly consistent with increased proliferation and decreased differentiation. Transcript levels of c-fos (associated with cell proliferation) trended higher after 3, 7, and 14 days in culture. Also, expression of alkaline phosphatase, osteonectin, osterix, and osteopontin, which are markers for osteoblast differentiation, showed MK-induced decreases in a cell type and time dependent manner. Taken together, these data suggest that MK play a role in stromal cell proliferation and differentiation, from multiple sites/locations in multiple species

A Plasmodium Whole-Genome Synteny Map: Indels and Synteny Breakpoints as Foci for Species-Specific Genes

Whole-genome comparisons are highly informative regarding genome evolution and can reveal the conservation of genome organization and gene content, gene regulatory elements, and presence of species-specific genes. Initial comparative genome analyses of the human malaria parasite Plasmodium falciparum and rodent malaria parasites (RMPs) revealed a core set of 4,500 Plasmodium orthologs located in the highly syntenic central regions of the chromosomes that sharply defined the boundaries of the variable subtelomeric regions. We used composite RMP contigs, based on partial DNA sequences of three RMPs, to generate a whole-genome synteny map of P. falciparum and the RMPs. The core regions of the 14 chromosomes of P. falciparum and the RMPs are organized in 36 synteny blocks, representing groups of genes that have been stably inherited since these malaria species diverged, but whose relative organization has altered as a result of a predicted minimum of 15 recombination events. P. falciparum-specific genes and gene families are found in the variable subtelomeric regions (575 genes), at synteny breakpoints (42 genes), and as intrasyntenic indels (126 genes). Of the 168 non-subtelomeric P. falciparum genes, including two newly discovered gene families, 68% are predicted to be exported to the surface of the blood stage parasite or infected erythrocyte. Chromosomal rearrangements are implicated in the generation and dispersal of P. falciparum-specific gene families, including one encoding receptor-associated protein kinases. The data show that both synteny breakpoints and intrasyntenic indels can be foci for species-specific genes with a predicted role in host-parasite interactions and suggest that, besides rearrangements in the subtelomeric regions, chromosomal rearrangements may also be involved in the generation of species-specific gene families. A majority of these genes are expressed in blood stages, suggesting that the vertebrate host exerts a greater selective pressure than the mosquito vector, resulting in the acquisition of diversity

The OASI care bundle quality improvement project: lessons learned and future direction.

Rising rates of obstetric anal sphincter injury (OASI) led to a collaborative effort by the Royal College of Obstetricians and Gynaecologists (RCOG) and the Royal College of Midwives (RCM) to develop and evaluate the OASI Care Bundle (OASI-CB). The OASI-CB comprises four practices (antenatal discussion about OASI, manual perineal protection, mediolateral episiotomy at 60° from the midline, and systematic examination of the perineum, vagina and ano-rectum after vaginal birth) and was initially implemented as part of a quality improvement (QI) project-"OASI1"-in 16 maternity units across Great Britain. Evaluation of the OASI1 project found that the care bundle reduced OASI rates and identified several barriers and enablers to implementation. This paper summarises the key findings, including strengths, limitations and lessons learned from the OASI1 QI project, and provides rationale for further evaluation of the OASI-CB

Women's experiences of the OASI Care Bundle; a package of care to reduce severe perineal trauma.

INTRODUCTION AND HYPOTHESIS: Obstetric anal sphincter injury (OASI) is a severe form of perineal trauma that can occur during vaginal birth. Long-term morbidities include anal incontinence and psychosocial disorders. To reduce these injuries within England, Scotland and Wales, the OASI Care Bundle was introduced to 16 maternity units (January 2017-March 2018). The OASI Care Bundle comprises four elements: (1) antenatal information, (2) manual perineal protection, (3) medio-lateral episiotomy (when indicated) and 4) recognition and diagnosis of tears. As part of the project evaluation, a qualitative study was conducted to explore women's experiences of the OASI Care Bundle. METHODS: Semi-structured interviews were conducted with women (n = 19) who received the OASI Care Bundle as part of their maternity care. This was to explore their experience of each element. A thematic analysis of the interview data was performed. RESULTS: Three themes were identified: (1) memories of touch, whereby women reported that a 'hands-on' approach to perineal protection was a positive experience; (2) midwife as a supportive guide, where women reported that good communication facilitated a calm birth and post-birth diagnosis; (3) education: women need more information about perineal trauma. CONCLUSION: This study contributes to the literature through its exploration of women's experiences of perineal protection techniques and diagnosis of perineal trauma. Interviewed women indicated that they did not experience any of the care bundle elements as an intrusion of their physical integrity. Additionally, an urgent need was identified for more information about perineal trauma in terms of risk, prevention and recovery

Biological response to pre-mineralized starch based scaffolds for bone tissue engineering

It is known that calcium-phosphate (Ca-P) coatings are able not only to improve the bone bonding behaviour of polymeric materials, but at the same time play a positive role on enhancing cell adhesion and inducing the differentiation of osteoprogenitor cells. Recently an innovative biomimetic methodology, in which a sodium silicate gel was used as a nucleative agent, was proposed as an alternative to the currently available biomimetic coating methodologies. This methodology is especially adequate for coating biodegradable porous scaffolds. In the present work we evaluated the influence of the referred to treatment on the mechanical properties of 50/50 (wt%) blend of corn starch/ethylene-vinyl alcohol (SEVA-C) based scaffolds. These Ca-P coated scaffolds presented a compressive modulus of 224.6 ± 20.6 and a compressive strength of 24.2 ± 2.20. Cytotoxicity evaluation was performed according ISO/EN 10993 part 5 guidelines and showed that the biomimetic treatment did not have any deleterious effect on L929 cells and did not inhibit cell growth. Direct contact assays were done by using a cell line of human osteoblast like cells (SaOS-2). 3 × 105 cells were seeded per scaffold and allowed to grow for two weeks at 37 ◦C in a humidified atmosphere containing 5% CO2. Total protein quantification and scanning electron microscopy (SEM) observation showed that cells were able to grow in the pre-mineralized scaffolds. Furthermore cell viability assays (MTS test) also show that cells remain viable after two weeks in culture. Finally, protein expression studies showed that after two weeks osteopontin and collagen type I were being expressed by SaOS-2 cells seeded on the pre-mineralized scaffolds. Moreover, alkaline phosphatase (ALP) activity was higher in the supernatants collected from the pre-mineralized samples, when compared to the control samples (non Ca-P coated). This may indicate that a faster mineralization of the ECM produced on the pre-mineralized samples was occurring. Consequently, biomimetic pre-mineralization of starch based scaffolds can be a useful route for applying these materials on bone tissue engineering

OASI2: a cluster randomised hybrid evaluation of strategies for sustainable implementation of the Obstetric Anal Sphincter Injury Care Bundle in maternity units in Great Britain.

BACKGROUND: The Obstetric Anal Sphincter Injury (OASI) Care Bundle comprises four primary and secondary prevention practices that target the rising rates of severe perineal tearing during childbirth, which can have severe debilitating consequences for women. The OASI Care Bundle was implemented in 16 maternity units in Britain in the OASI1 project (2017-2018), which demonstrated the care bundle's effectiveness in reducing OASI rates. In OASI2, the care bundle will be scaled up to 20 additional National Health Service (NHS) maternity units in a hybrid effectiveness-implementation study that will examine the effectiveness of strategies used to introduce, implement and sustain the care bundle. METHODS: OASI2 is a two-arm cluster-randomised control trial (C-RCT) of maternity units in England, Scotland and Wales, with an additional non-randomised study arm. C-RCT arm 1 (peer support, n = 10 units) will be supported by 'buddy' units to implement the OASI Care Bundle. C-RCT arm 2 (lean implementation, n = 10 units) will implement without external support. The additional study arm (sustainability, n = 10 units) will include some original OASI1 units to evaluate the care bundle's sustainability and OASI rates over time, from before OASI1 and through the end of OASI2. Units in all three study arms will receive an Implementation Toolkit with training resources and implementation support. The C-RCT arms will be compared in terms of OASI rate reduction (primary effectiveness outcome) and clinicians' adoption of the care bundle (primary implementation outcome). Clinical data will be collated from maternity information systems; implementation data will be collected through validated surveys with women and clinicians, supplemented by qualitative methods. Descriptive statistics and regression modelling will be used for analysis. Emergent themes from the qualitative data will be assessed using framework analysis. DISCUSSION: OASI2 will study the impact of various implementation strategies used to introduce and sustain the OASI Care Bundle, and how these strategies affect the bundle's clinical effectiveness. The study will generate insights into how to effectively scale-up and sustain uptake and coverage of similar interventions in maternity units. A locally adaptable 'implementation blueprint' will be produced to inform development of future guidelines to prevent perineal trauma. TRIAL REGISTRATION: ISRCTN26523605