GuatemalaCobblestone LissencephalyIndians, Central AmericanCentral AmericaHematopoietic Stem CellsWalker-Warburg SyndromeTriatomaColony-Forming Units AssayHomeless YouthEl SalvadorHondurasInsect ControlAntigens, CD34Street DrugsDystroglycansBone Marrow CellsHematopoiesisMexicoCell Culture TechniquesMannosyltransferasesCells, CulturedFetal BloodStromal CellsLatin AmericaChagas Disease