RESUMEN
Germinal matrix-intraventricular hemorrhage (GM-IVH) is a detrimental neurological complication that occurs in preterm infants, especially in babies born before 32 weeks of gestation and in those with a very low birth weight. GM-IVH is defined as a rupture of the immature and fragile capillaries located in the subependymal germinal matrix zone of the preterm infant brain, and it can lead to detrimental neurological sequelae such as posthemorrhagic hydrocephalus (PHH), cerebral palsy, and other cognitive impairments. PHH following GM-IVH is difficult to treat in the clinic, and no levelone strategies have been recommended to pediatric neurosurgeons. Several cellular and molecular mechanisms of PHH following GM-IVH have been studied in animal models, but no effective pharmacological strategies have been used in the clinic. Thus, a comprehensive understanding of molecular mechanisms, potential pharmacological strategies, and surgical management of PHH is urgently needed. The present review presents a synopsis of the pathogenesis, diagnosis, and cellular and molecular mechanisms of PHH following GM-IVH and explores pharmacological strategies and surgical management.
RESUMEN
Tropical lotus (Nelumbo) is an important and unique ecological type of lotus germplasm. Understanding the genetic relationship and diversity of the tropical lotus is necessary for its sustainable conservation and utilization. Using 42 EST-SSR (expressed sequence tag-simple sequence repeats) and 30 SRAP (sequence-related amplified polymorphism) markers, we assessed the genetic diversity and inferred the ancestry of representative tropical lotus from Thailand and Vietnam. In total, 164 and 41 polymorphic bands were detected in 69 accessions by 36 EST-SSR and seven SRAP makers, respectively. Higher genetic diversity was revealed in Thai lotus than in Vietnamese lotus. A Neighbor-Joining tree of five main clusters was constructed using combined EST-SSR and SRAP markers. Cluster I included 17 accessions of Thai lotus; cluster II contained three Thai accessions and 11 accessions from southern Vietnam; and cluster III was constituted by 13 accessions of seed lotus. Consistent with the results from the Neighbor-Joining tree, the genetic structure analysis showed that the genetic background of most Thai and Vietnamese lotus was pure, as artificial breeding has been rare in both countries. Furthermore, these analyses indicate that Thai and Vietnamese lotus germplasms belong to two different gene pools or populations. Most lotus accessions are genetically related to geographical distribution patterns in Thailand or Vietnam. Our findings showed that the origin or genetic relationships of some unidentified lotus sources can be evaluated by comparing morphological characteristics and the data of molecular markers. In addition, these findings provide reliable information for the targeted conservation of tropical lotus and parent selection in breeding novel cultivars of lotus.