The hemopoietic microenvironment : effects of chemotherapy and irradiation

Blood consists of plasma containing cells and cell fragments. Three groups of blood cells can be identified, namely (a) red blood cells or erythrocytes, (b) white blood cells or leucocytes and (c) platelets or thrombocytes. The white blood cells can be separated into neutrophilic-, eosinophilic- and basophilic granulocytes, lymphocytes and monocytes. The life time of these cells is limited. For example, in man life time for normal erythrocytes is about 120 days and for granulocytes a few days. The daily production of these cells required to maintain normal numbers in blood can be calculated from their life span, their concentration in the blood and the total blood volume. Thus, an adult human male produces approximately 2 x 10¹¹ erythrocytes and 1 x 10¹⁰ granulocytes every day. These amounts are necessary for normal maintenance but the production of blood cells can be increased after stress, for example, infection or blood los

Histological findings in unclassified sudden infant death, including sudden infant death syndrome

Our objective was to study histological variations and abnormalities in unclassified sudden infant death (USID), including sudden infant death syndrome (SIDS), in The Netherlands. Two hundred Dutch USID cases between 1984 and 2005 were identified. The histology slides and autopsy reports of 187 cases were available for systematic review, including brain autopsy in 135 cases. An explanation for the cause of death in 19 patients (10.2+ACU-) was found. Twelve patients had bronchopneumonia, 3 showed extensive aspiration, 2 had signs of a metabolic disorder, 1 had sepsis, and 1 had meningitis. Frequent nonspecific findings were congestion (66+ACU-), edema (47+ACU-), small hemorrhages (18+ACU-), and lymphoid aggregates (51+ACU-) in the lungs; congestion of the liver (23+ACU-); and asphyctic bleeding in the kidney (44+ACU-), adrenal gland (23+ACU-), and thymus (17+ACU-). Statistical associations were found for infection with starry sky macrophages in the thymus (P 5 0.004), with calcification (P 5 0.023), or with debris in the Hassal's corpuscles (P 5 0.034). In this study, in 10.2+ACU- of cases the histological findings were incompatible with SIDS or USID. Furthermore, several frequent nonspecific histological findings in the thymus that point toward an infection were found

5q11.2 deletion in a patient with tracheal agenesis

Tracheal agenesis (TA) is a rare congenital anomaly of the respiratory tract. Many patients have associated anomalies, suggesting a syndromal phenotype. In a cohort of 12 patients, we aimed to detect copy number variations. In addition to routine cytogenetic analysis, we a