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Background and Objective: Lectins are carbohydrate-binding proteins of plants or animal origin, which react with terminal sugars of glycoconjugates of cells and tissues. Glycoconjugates play essential role in several biological phenomena such as Cell recognition, proliferation, migration and differentiation. Notochord, a mesodermal derivative, induces nearby tissues, including Neural tube, sometimes and developing gut. Materials and Methods: The purpose of this study was to investigate distribution of glycoconjugates in component of notochord and axial vessels during mouse embryonic development. Results: Formalin fixed sections embedded in paraffin from 9 to 14 embryonic days of Balb/c mice were processed for histochemical studies by using four different horseradish peroxidase (HRP) labeled lectins including: Glycin Max (SBA), Vicia Villosa (VVA) and Maclura Pomifera (MPA) specific for GalNac terminal sugar and Lotus Tetragonolobus (LTA) that bind to ?-L-fucose terminal sugar. Our results revealed that approximately similar reactions were observed in notochord and axial vessels endothelium by using GalNac sensitive lectins during vessels morphogenesis. Fucose sensitive lectin reacted only with the notochord. The time and significant role(s) in tissue interactions and subsequent formation of adjacent tissues such as: Axial vessels development during critical morphogenic period. Conclusion: Furthermore, our findings indicate that fucosylated glycoconjugates may have no role in axial vessel formation and/or their interactions with the notochord during early morphogenic period.

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Background&Objective: Carbohydrate chains link to glycoproteins and glycolipids of the cell surface particulary their terminal sugars have key roles in cellular activities of almost all biological systems. Distribution of these glycoconjugates in adult kidney has not received fair attention yet. The purpose of this study was to identify in situ location of galactose – N – acetyle galactoseamine moleucles on the surface of the adult rat kidney. Materials&Methods: After the resection of rat kidney and rotin fixation with regular lectin histochemical technique, MPA and PNA conjugated to horseradish peroxidase, lectins specific to indentify these terminal sugars in rat kidney. Results: Intense reaction of PNA to collective tubules, less intense and reaction with luminal surface of proximal tubules and MPA identified distinct cells among distal tubules as well as glomerules were observed. Conclusion: It seems that this specific sugars related to the cellulars function of this region of adult kidney and probably genetically is regulated during embryonic development.

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Background and Objective: Change in the cell surface and extracellular matrix glycoconjugates has been reported in many cancers. Moreover, diagnostic and prognostic importance of these substances and also their roles in therapeutic modalities for cancerous patients has been emphasized. This study was designed to explore the histochemical study of cellular mucopolysaccharides in esophageal and gastric carcinoma and its relation to tumor differentiation. Materials and Methods: In this laboratory study tissue samples of 40 patients with esophageal squamous cell carcinoma and 40 patients with stomach adenocarcinoma in different grades of tumor were selected from pathology department of Emam Reza hospital in Mashhad, Iran. Tissue samples were stained with Alcian Blue (PH 1 and PH 2.5) for Sulfated and Carboxylated mucosubstances respectively, along with positive and negative controls. Results: Normal esophageal epithelium and carcinoma cells of different grades showed negative reactivity but normal and tumoral stromal cells depicted positive staining in both PHs. In PH 1, normal glandular and carcinoma cells of the stomach were negative but in PH 2 glandular cells were positive though carcinoma cells showed weakly staining. Normal and tumoral gastric stromal cells showed positive staining in PH 1 and PH 2.5. Conclusion: It is highly probable that in the process of cancerization of normal esophageal squamous cells, functional changes, from the perspective of producing Carboxylated and Sulfated mucosubstances, do not occur, whereas some changes in glandular cells of stomach which result in diminishing the production of Carboxylated mucosubstances during cancerization process are observable.

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Background and Objective: The neurohypophysis originates from the floor of diencephalon. Its development controles by several cellular interactions that mediated by some molecules such as cell surface and extra cellular matrix Glycoconjugates terminal sugars. In this study we used lectin histochemichal technique to evaluate distribution of the Glycoconjugates and their changes during development of neurohypophysis. Materials and Methods: This experimental study carried on 40 female and 20 male adult Rats. After mating and appointment day zero of pregnancy, pregnant Rats were sacrificed from days 10-20 of gestation and their embryos were collected for histochemical study. The serial section of head specimens were fixed and incubated with different HRP-lectins from Orange fungus (OFA) Vicica villosa (VVA), Glycine max (SBA), Wistaria floribunda (WFA), peanut (PNA), Griffonia simplicfolia (GSA1-B4), Lotus tetragonolobus (LTA) and Ulex Europeus (UEA-1). OFA, LTA and UEA-1 lectins are specific for terminal sugars α-L–Fucose and WFA, SBA, VVA and PNA are specific for D-GalNAc, α, ß-D-GalNAc and GalNAc, D-Gal-(ß-1-3)- D-GalNAc of complex glycoconjugates respectively. Results: Our findings demonstrated that the reaction of neurohypophysis cells with OFA initiated from gestational GD10 and increased to GD15 (P<0.05) and then increased to GD17 (P<0.05). A few cells of neurohypophysis reacted with PNA from GD13 to GD16 and decreased afterward (P<0.05). Some cells of neurohypophysis reacted with SBA from GD14 to GD18 and decreased afterward (P<0.05). Reacting of many cells of neurohypophysis with WFA started on GD13 and increased to GD15 (P<0.05) and then decreased afterward (P<0.05). Neurohypophysis cells showed no reaction with the UEA-1, LTA, VVA and GSA1-B4 lectins. Conclusion: The expression of Glycoconjugates with terminal sugars α-L–Fucose, α, ß-D-GalNAc and D- Gal– (ß-1-3)- D-GalNAc have importanct role and special spatiotemporal situation in neurohypophysis development.