No abstract

This study was undertaken to review our approach to diagnosis and treatment in a series of 11 patients (mean age 8.2 years) with primary pyomyositis, who had neither an underlying disease nor a compromised immune system. Nine of the children had positive blood cultures, Staphylococcus aureus (eight) and Streptococcus group A (one). The sites of infection were iliopsoas (four), obturator (two), hip adductors (two), levator scapula (one), thoracolumbar paraspinal (one) and gastrocnemius (one) muscles. Antibiotic treatment was initially intravenous, followed by oral administration. Of five patients with evidence of abscess formation, three underwent percutaneous drainage, whereas two required open surgical drainage. The infection resolved completely without any sequela in 10 children. One patient who developed acute compartment syndrome showed late signs of osteonecrosis of the tibial shaft segment.

No abstract

The marrow stromal cells (MSC) are essential for regulation of bone remodeling and hematopoiesis. It is of prime importance to isolate MSC and to expand the proliferating cells ex vivo. In this study, we analyzed cultured MSC for various cellular parameters, including cell morphology, cell cycle, and expression of cell surface antigens by flow cytometry. MSC were divided based on cell size to small (S-cells) and large (L-cells) and were visualized by light and electron microscope. The S-cells were proliferating cells correlated with G0/G1 phase of cell cycle, and expressed cFOS. The expression of surface markers CD-34, -44, -51, -61, -62E, -62P, -62L was quantified using flow cytometry. CD-44 was ubiquitously expressed by S and L cells, CD-51 and -61 were expressed by 30%-38% of S-cells. CD-34 and -62 expressed 20% positive of the analyzed cells that were of the proliferating progenitors (S-cells). This study enables the identification of subpopulations from MSC with special attention paid to the proliferating cells from ex vivo cultures of marrow stroma.