The t(8;21)-encoded AML1-ETO chimeric product is believed to be causally involved in up to 15% of acute myelogenous leukemias through an as yet unknown mechanism. To directly investigate the role of AML1-ETO in leukemogenesis, we used gene targeting to create an AML1-ETO "knock-in" allele that mimics the t(8;21). Unexpectedly, embryos heterozygous for AML1-ETO (AML1-ETO/+) died around E13.5 fro...

Small circulating megakaryocytes were nuclear. The circulating megakaryocytes identified in four patients with chronic were associated with the presence of myeloproliferative disorders, and their dysplastic platelets. Both findings are morphologic features by light and electron thought to represent involvement of the microscopy are described. The morphomegakaryocytic-platelet line, probably as ...

We reviewed 29 cases of congenital multicystic dysplastic kidneys. Isolated renal pelvic atresia has an excellent prognosis but lower ureteral atresias are associated with a high incidence of contralateral renal disease and have a worse prognosis.

Cross-linking of major histocompatibility complex (MHC) class II antigens by anti-HLA-DR monoclonal antibody (MoAb; H81.9; IgG2a) results in inhibition of hematopoiesis in canine and human models. Inhibition of hematopoiesis is associated with apoptosis in a proportion of marrow cells. Since in murine macrophages class II cross-linking triggers nitric oxide (NO) production, and NO is thought to...

Background. Extramedullary hematopoiesis is most often seen in reticuloendothelial organs specially spleen, liver, or lymph nodes, and it is rarely seen in lung parenchyma. Almost all reported cases of pulmonary extramedullary hematopoiesis occurred following myeloproliferative disorders specially myelofibrosis. Other less common underlying causes are thalassemia syndromes and other hemoglobino...

Hematopoiesis is a dynamic process where initiation and maintenance of hematopoietic stem cells, as well as their differentiation into erythroid, myeloid and lymphoid lineages, are tightly regulated by a network of transcription factors. Understanding the genetic controls of hematopoiesis is crucial as perturbations in hematopoiesis lead to diseases such as anemia, thrombocytopenia, or cancers,...

Ichthyosis uteri is a rare condition in which the entire surface of the endometrium is replaced by stratified squamous epithelium. Though the condition often is considered as benign, anaplastic and dysplastic changes have been reported. We describe herein a rare case of low-grade squamous cell carcinoma of endometrium associated with extensive ichthyosis uteri with dysplasia. The cervix showed ...

Abnormal hip development causes one-quarter to one-half of all hip disease. Dysplastic hips typically share characteristic anatomic abnormalities. The dysplastic acetabulum is typically shallow, lateralized, and anteverted with insufficient coverage anteriorly, superiorly, and laterally. The dysplastic proximal femur has a small femoral head with excessive femoral neck anteversion and a short n...

Hepatocellular carcinoma may develop from multistep carcinogenesis via dysplastic nodules in the cirrhotic liver. The first stage between high-grade dysplastic nodule to overt hepatocellular carcinoma is vaguely nodular, early hepatocellular carcinoma. The consensus on the nomenclature and pathologic characteristics of both entities were recently established by an international consensus group ...

The spleen is a major site for extramedullary hematopoiesis and adult mouse and human spleens retain low numbers of hematopoietic stem cells (HSC). Hematopoiesis is however dependent on stromal microenvironments that provide appropriate molecular signals. Recent evidence now suggests that a distinct stromal cell type exists in the spleen which can function as a niche for hematopoiesis. This rev...