Hereditary hair loss and the ancient signaling pathways that regulate ectodermal appendage formation

All epidermal appendages, including hair, teeth, and nails, begin as a thickening of the ectoderm, called a placode. The placode arises from a primary induction signal that is sent from the underlying mesenchyme to the overlying epidermis. In mammals, the precise arrangement of hair follicles in the skin is due to the amount and distribution of signals that promote and inhibit hair placode formation. Continued development of a hair follicle after placode formation requires a complex cross-talk between the mesenchyme and epidermis. Here, I will review recent studies in humans and mice that have increased our understanding of the role of these signaling pathways in normal development and in hereditary hair loss syndromes. The study of normal hair development may suggest ways to restore or eliminate hair and might identify possible targets for the therapy of basal cell carcinoma, a cancer which strongly resembles embryonic hair follicles.     

美国国家骨髓库20年回顾:捐献活动和非家族异体造血移植产品性能

异基因造血细胞移植已被广泛用于恶性血液疾病、非恶性血液疾病,以及其他疾病的治疗.自1987年来,NMDP实施了以下工作:捐献者身份确认、从匹配的捐献者采集干细胞、运输并输注给没有合适亲缘捐献者的患者.随着移植技术发展,良好的辅助医疗支持以及HLA配型的规范化,越来越多的NMDP产品应用于不同的患者.充足造血干细胞的捐献者是保证造血干细胞移植(HCT)成功的重要因素,然而,通过这些大量数据,可分析捐献者个体的捐献经验和HCT产品的特性.本文研究了NMDP捐献者的捐献活动,它包括多次BM捐献,PBSC捐献以及用于支持免疫重建、提供输血支持、治疗移植后并发症的辅助产品的捐献.本文还对影响HCT产品完整性的诸如采集袋破损、肉眼凝块的情况进行了总结.     

Chromosomal abnormalities identify high-risk and low-risk patients with acute lymphoblastic leukemia

The importance of banded chromosome analyses in predicting long-term outcome in acute lymphoblastic leukemia (ALL) was evaluated in this follow-up study of 329 patients from the Third International Workshop on Chromosomes in Leukemia. Patients were divided into ten groups according to pretreatment karyotype: no abnormalities, one of the following structural abnormalities [the Philadelphia chromosome, translocations involving 8q24,t(4;11), 14q+, 6q-] or, in the remaining cases, modal number [less than 46, 46, 47 to 50, greater than 50]. Achievement and duration of complete remission (CR) and survival differed among chromosome groups (P less than .0001). Karyotype was an independent prognostic factor for duration of first CR and survival, even when age, initial leukocyte count (WBC), French-American-British (FAB) type, and immunologic phenotype were considered. Among adults, prolonged remission and survival were uncommon in all chromosome groups. Only in the normal karyotype group was median survival even two years. Among children, striking differences in long-term remission and survival were seen depending upon karyotype. Children in the greater than 50 group did best, with 70% remaining in first CR for a median duration in excess of five years. Children in the 47-50, 6q-, and normal karyotype groups also had prolonged survivals. In contrast, certain translocations [t(9;22)(q34;q11), t(4;11)(q21;q14-23), t(8;14)(q24;q32)] identified children who had short survivals, even in the presence of favorable prognostic factors including a low WBC, L1 morphology, and non-T, non-B immunologic phenotype. We conclude that chromosome analysis is required at diagnosis in patients with ALL, and that children with these specific translocations should be managed as having high-risk ALL.