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Lectin Histochemical Study of Cell Surface Glycoconjugate in Gastric Carcinoma Using Helix Pomatia Agglutinin
Mohammad Reza Arab,Somayeh Salari,Mehrbod Karimi,Hasan Mofidpour
Acta Medica Iranica , 2010,
Abstract: "nAltered glycosylation of proteins in cancer cells is one of the main processes responsible for anaplasia, invasion and metastatic potential of neoplastic cells. Lectins are nonimmunogenetic compounds which specifically detect certain terminal sugars of glycoconjugates. The aim of the present study was to identify the N-acetylgalactosamine (GalNac) containing glycoconjugates in cancer cells in all grades of gastric carcinoma. Paraffin blocks belong to 30 patients of gastric carcinoma (10 cases from each grade) was collected from pathology file of Ali-Ebn-Abitaleb Hospital in Zahedan during 2005-2007. Prepared sections (5-7μm in thickness) were stained by Alcian Blue, hematoxylin and eosin (H&E) and helix pomatia agglutinin (HPA) conjugated lectin. Lectin diluted up to 10μg/ml in PBS (0.1M, pH=6.8). Lectin reactivity was visualized by 0.03% diaminobenzidine (DAB) solution. Sections were graded according to staining intensity to lectin (0-4+). Although there was some difference for lectin staining intensity between cancer cells in different grades of gastric carcinoma, statistical analysis showed that there was only a significant difference for cancer cells reactivity between histopathological grades of II and III. The pattern of reactivity to HPA lectin were also different from all histopathological grades. It seems that in cancer cells, the amount and distribution of GalNac containing glycoconjugate differ from neoplastic cells of different histopathological grades in gastric carcinoma.
Purification and characterisation of a lectin from the red marine alga Pterocladiella capillacea (S.G. Gmel.) Santel. & Hommers.
OLIVEIRA STéLIO R.M.,NASCIMENTO ANTONIA E.,LIMA MARIA E.P.,LEITE YáSKARA F.M.M.
Brazilian Journal of Botany , 2002,
Abstract: A lectin present in the marine red alga Pterocladiella capillacea was purified and characterised by extraction of soluble proteins (crude extract) in 20 mM Tris-HCl buffer, pH 7.5. Among the analysed erythrocytes (human blood group A, B and O and the animals ox, goat, chicken and rabbit) the lectin agglutinated specifically rabbit erythrocytes. The hemagglutinating activity assay showed that the lectin was not dependent on divalent cations and was shown to be inhibited by the glycoproteins avidin and mucin. The purification procedure was conduced by precipitation of the crude extract with 80% saturation ammonium sulfate (F0/80) followed by affinity chromatography on guar-gum column. The lectin of P. capillacea was purified 14.5 fold and had a recovery of 27.4% of the original total specific activity present in the crude extract. The absence of carbohydrate suggested that the lectin is not a glycoprotein. The molecular mass of P. capillacea lectin, determined by gel filtration, was 5.8 kDa. SDS-PAGE in the presence of -mercaptoethanol gave one band, indicating that the native lectin is a monomeric protein. The activation energy of denaturation process (D G') was calculated to be 106.87 kJ . mol-1 at 70 masculineC.
Purification and partial characterisation of a lectin from the red marine alga Vidalia obtusiloba C. Agardh
Melo, Fábio R.;Benevides, Norma M.B.;Pereira, Maria G.;Holanda, Márjory L.;Mendes, Francisca N.P.;Oliveira, Stélio R.M.;Freitas, Ana L.P.;Silva, Luana M.C.M.;
Brazilian Journal of Botany , 2004, DOI: 10.1590/S0100-84042004000200006
Abstract: the lectin of the red marine alga vidalia obtusiloba was purified by a combination of ammonium sulphate precipitation, ion-exchange chromatography on deae-cellulose and affinity chromatography on cross-linked guar gum. the lectin preferentially agglutinated native and bromelain-treated human group o erythrocytes. the haemagglutinating activity revealed that the lectin was dependent on divalent cations (ca++ or mn++) and was shown to be inhibited by n-acetyl-galactosamine, d-galactosamine, a-lactose and d-galactose and by the glycoprotein porcine stomach mucin. the molecular mass of the lectin, estimated by gel filtration, was 78.9 kda while by sds-page, in the presence of b-mercaptoethanol, the lectin exhibited two different protein subunits with mr of 59.6 and 15.2 kda, suggesting that the lectin is a dimeric protein. isoelectric focusing revealed the presence of a simple acidic protein with an isoelectric point between 4 and 5. the purified lectin showed a carbohydrate content of 43.2% and a predominance of the amino acids asp/asn, glu/gln and leu. the energy of activation (dg') for the denaturation of the lectin was estimated to be 25.4 kcal.mol-1 at 90 oc. immunochemical assays using a rabbit antiserum raised against the purified lectin of v. obtusiloba showed that it was possible to detect the presence of the lectin at different steps of the purification process. western blotting of sds-page gels showed immunostaining of only the larger of the lectin subunits.
Antinociceptive properties in mice of a lectin isolated from the marine alga Amansia multifida Lamouroux
Neves, S.A.;Freitas, A.L.P.;Souza, B.W.S.;Rocha, M.L.A.;Correia, M.V.O.;Sampaio, D.A.;Viana, G.S.B.;
Brazilian Journal of Medical and Biological Research , 2007, DOI: 10.1590/S0100-879X2007000100016
Abstract: the antinociceptive effects of a lectin (lec) isolated from the marine alga amansia multifida were determined in swiss mice. the lec (1, 5, and 10 mg/kg) inhibited acetic acid-induced abdominal writhings in a dose-dependent manner after intraperitoneal or oral administration. a partial but significant inhibition of writhings was observed after the combination of lec (10 mg/kg) with avidin (1 mg/kg), a potent inhibitor of the hemmaglutinant activity of the lectin. however, total writhing inhibition was demonstrable in the group of mice treated with lec plus mannose (1 mg/kg), as compared to lec alone or to control groups. furthermore, avidin and mainly mannose also play a role in antinociception, somehow facilitating the interaction of lec with its active cell sites. in the formalin test, although both phases of the response were significantly inhibited, the effect of lec was predominant during phase 2, causing inhibition of licking time that ranged from 48 to 88% after oral (5 and 10 mg/kg) and intraperitoneal (1 to 5 mg/kg) administration. as is the case with morphine, the effect of lec (2 mg/kg) was reversed by naloxone (2 mg/kg), indicating the involvement of the opioid system. lec was also effective in the hot-plate test, producing inhibitory responses to the thermal stimulus, and its effects were blocked by naloxone. in the pentobarbital-induced sleeping time, although lec did not alter the onset of sleep significantly, it increased the time of sleep within the same dose range compared to control. these results show that lec presents antinociceptive effects of both central and peripheral origin, possibly involving the participation of the opioid system.
Molecular characterization of a lectin, BPL-4, from the marine green alga Bryopsis plumosa (Chlorophyta)  [PDF]
Jong Won Han,Kang Sup Yoon,Min Gui Jung,Kyong-Hwa Chah
Algae , 2012,
Abstract: A novel lectin specific to N-acetyl-D-galactosamine as well as N-acetyl-D-glucosamine was isolated from Bryopsis plumosaand named as BPL-4. Sodium dodecyl sulfate polyacrylamide gel electrophorese (SDS-PAGE) and matrix-assistedlaser desorption / ionization-time of flight (MALDI-TOF) mass spectrometry data showed that this lectin was a monomericprotein with molecular weight 12.9 kDa. The N-terminal amino acid sequences of the lectin were determined byEdman degradation and the full cDNA sequence encoding this lectin was obtained using the degenerate primers designedfrom the amino acid sequence. The size of the cDNA was 414 bp containing single open reading frame (ORF) encodingthe lectin precursor. The homology analysis showed that this lectin might belong to H lectin group. BPL-4 showedhigh sequence similarity (60.6%) to BPL-3, which is a previously reported lectin from the same species. The comparativeanalysis on the lectin’s primary structure showed two conserved domains including one possible active domain of Hlectin group.
Evaluation of acrosomal status and sperm viability in fresh and cryopreserved specimens by the use of fluorescent peanut agglutinin lectin in conjunction with hypo-osmotic swelling test
Esteves, Sandro C.;Sharma, Rakesh K.;Thomas Jr, Anthony J.;Agarwal, Ashok;
International braz j urol , 2007, DOI: 10.1590/S1677-55382007000300009
Abstract: objective: in this study, we evaluated whether the hypo-osmotic swelling test (host) can be used as a vital marker in combination with peanut agglutinin (pna) - labeling in fresh and cryopreserved spermatozoa. materials and methods: human sperm populations were exposed to a hypo-osmotic medium for 60 minutes, and then incubated in a 1 μg/ml solution of the fluorescent dye hoescht 33258 (h33258) for 10 minutes. excess stain was removed by washing in phosphate-buffered saline (pbs) solution, and the pellet was resuspended in 100 μl of culture medium. twenty microliters of this solution were subsequently smeared on a microscope slide, and fixed in ice-cold methanol to permeabilize the sperm membranes. the fixed smears were finally incubated in a 40-μg/ml fitc-pna solution for 20 minutes. simultaneous assessment of acrosome and viability scores was done in a fluorescent microscope equipped with appropriate filters and phase contrast illumination. the same slide was examined for fitc-pna labeling, tail swelling, and for hoechst-33258 staining by interchanging the filters and phase contrast optics. results: in fresh specimens, host was found to provide viability assessments comparable to those obtained using the h33258 method (r = 0.95). however, the results of host and h33258 were not correlated in cryopreserved specimens (r = 0.22). there was no alteration of pna-labeling due to the host or h33258. conclusions: fitc-pna labeling in conjunction with the visualization of the morphological change induced by exposure to hypo-osmotic solution provides a simple but effective method for establishing the state of acrosomal membrane and viability in fresh human spermatozoa, but this technique is not reliable for cryopreserved ones.
Inflammatory and anti-inflammatory effects of soybean agglutinin
Brazilian Journal of Medical and Biological Research , 1997, DOI: 10.1590/S0100-879X1997000700009
Abstract: soybean agglutinin (sba) lectin, a protein present in raw soybean meals, can bind to and be extensively endocytosed by intestinal epithelial cells, being nutritionally toxic for most animals. in the present study we show that sba (5-200 μg/cavity) injected into different cavities of rats induced a typical inflammatory response characterized by dose-dependent exudation and neutrophil migration 4 h after injection. this effect was blocked by pretreatment with glucocorticoid (0.5 mg/kg) or by co-injection of n-acetyl-galactosamine (100 x [m] lectin), but not of other sugars (100 x [m] lectin), suggesting an inflammatory response related to the lectin activity. neutrophil accumulation was not dependent on a direct effect of sba on the macrophage population since the effect was not altered when the number of peritoneal cells was increased or decreased in vivo. on the other hand, sba showed chemotactic activity for human neutrophils in vitro. a slight increase in mononuclear cells was observed 48 h after ip injection of sba. phenotypic analysis of these cells showed an increase in the cd4+/cd8- lymphocyte population that returned to control levels after 15 days, suggesting the development of an immune response. sba-stimulated macrophages presented an increase in the expression of cd11/cd18 surface molecules and showed some characteristics of activated cells. after intravenous administration, sba increased the number of circulating neutrophils and inhibited in a dose-dependent manner the neutrophil migration induced by ip injection of carrageenan into peritoneal cavities. the co-injection of n-acetyl-galactosamine or mannose, but not glucose or fucose, inhibited these effects. the data indicate that soybean lectin is able to induce a local inflammatory reaction but has an anti-inflammatory effect when present in circulating blood
Inflammatory and anti-inflammatory effects of soybean agglutinin  [cached]
Benjamin C.F.,Figueiredo R.C.,Henriques M.G.M.O.,Barja-Fidalgo C.
Brazilian Journal of Medical and Biological Research , 1997,
Abstract: Soybean agglutinin (SBA) lectin, a protein present in raw soybean meals, can bind to and be extensively endocytosed by intestinal epithelial cells, being nutritionally toxic for most animals. In the present study we show that SBA (5-200 μg/cavity) injected into different cavities of rats induced a typical inflammatory response characterized by dose-dependent exudation and neutrophil migration 4 h after injection. This effect was blocked by pretreatment with glucocorticoid (0.5 mg/kg) or by co-injection of N-acetyl-galactosamine (100 x [M] lectin), but not of other sugars (100 x [M] lectin), suggesting an inflammatory response related to the lectin activity. Neutrophil accumulation was not dependent on a direct effect of SBA on the macrophage population since the effect was not altered when the number of peritoneal cells was increased or decreased in vivo. On the other hand, SBA showed chemotactic activity for human neutrophils in vitro. A slight increase in mononuclear cells was observed 48 h after ip injection of SBA. Phenotypic analysis of these cells showed an increase in the CD4+/CD8- lymphocyte population that returned to control levels after 15 days, suggesting the development of an immune response. SBA-stimulated macrophages presented an increase in the expression of CD11/CD18 surface molecules and showed some characteristics of activated cells. After intravenous administration, SBA increased the number of circulating neutrophils and inhibited in a dose-dependent manner the neutrophil migration induced by ip injection of carrageenan into peritoneal cavities. The co-injection of N-acetyl-galactosamine or mannose, but not glucose or fucose, inhibited these effects. The data indicate that soybean lectin is able to induce a local inflammatory reaction but has an anti-inflammatory effect when present in circulating blood
Early events of secretory granule formation in the rat parotid acinar cell under the influence of isoproterenol. An ultrastructural and lectin cytochemical study  [cached]
F D’Amico,E Skarmoutsou,RM Imbesi,S Sanfilippo
European Journal of Histochemistry , 2009, DOI: 10.4081/1627
Abstract: The events involved in the maturation process of acinar secretory granules of rat parotid gland were investigated ultrastructurally and cytochemically by using a battery of four lectins [Triticum vulgaris agglutinin (WGA), Ulex europaeus agglutinin I (UEA-I), Glycine max agglutinin (SBA), Arachys hypogaea agglutinin (PNA)]. In order to facilitate the study, parotid glands were chronically stimulated with isoproterenol to induce secretion. Specimens were embedded in the Lowicryl K4M resin. The trans-Golgi network (TGN) derived secretory granules, which we refer to as immature secretory granules, were found to be intermediate structures in the biogenesis process of the secretory granules in the rat parotid acinar cell. These early structures do not seem to be the immediate precursor of the mature secretory granules: in fact, a subsequent interaction process between these early immature granule forms and TGN elements seems to occur, leading, finally, to the mature granules. These findings could explain the origin of the polymorphic subpopulations of the secretory granules in the normal acinar cells of the rat parotid gland. The lectin staining patterns were characteristic of each lectin. Immature and mature secretory gran- ules were labelled with WGA, SBA, PNA, and lightly with UEA-I. Cis and intermediate cisternae of the Golgi apparatus were labelled with WGA, and trans cisternae with WGA and SBA.
The Genetics of Osteosarcoma  [PDF]
Jeff W. Martin,Jeremy A. Squire,Maria Zielenska
Sarcoma , 2012, DOI: 10.1155/2012/627254
Abstract: Osteosarcoma is a primary bone malignancy with a particularly high incidence rate in children and adolescents relative to other age groups. The etiology of this often aggressive cancer is currently unknown, because complicated structural and numeric genomic rearrangements in cancer cells preclude understanding of tumour development. In addition, few consistent genetic changes that may indicate effective molecular therapeutic targets have been reported. However, high-resolution techniques continue to improve knowledge of distinct areas of the genome that are more commonly associated with osteosarcomas. Copy number gains at chromosomes 1p, 1q, 6p, 8q, and 17p as well as copy number losses at chromosomes 3q, 6q, 9, 10, 13, 17p, and 18q have been detected by numerous groups, but definitive oncogenes or tumour suppressor genes remain elusive with respect to many loci. In this paper, we examine studies of the genetics of osteosarcoma to comprehensively describe the heterogeneity and complexity of this cancer. 1. Introduction Osteosarcoma is the most common primary bone malignancy, with a high incidence rate in children and adolescents compared to other age groups. Tumours most often arise in the long bones from osteoid-producing neoplastic cells adjacent to the growth plates, occurring less commonly in the axial skeleton and other nonlong bones [1]. Survival rates for osteosarcoma have remained at 60–70% for localised disease for decades despite ongoing studies [2]. Unlike many sarcomas which are characterised by specific chromosome translocations, complex genomic rearrangements involving any chromosome characterise individual osteosarcoma cells. Because of this few consistent genetic changes that may indicate effective molecular targets for treatment have been reported. Decades’ worth of molecular cytogenetics studies and genomic analyses of osteosarcomas have been completed through karyotyping, comparative genomic hybridisation (CGH), fluorescence in situ hybridisation, quantitative PCR, and single-strand conformation polymorphism analysis, among others. Genome-wide association studies utilising single-nucleotide polymorphisms (SNPs) have been used more recently to learn more broadly about osteosarcoma genomics [3]. Resolution of alterations has increased from visualisation at the chromosome level to point mutations, but the genetic etiology of osteosarcoma is still unknown. One consistent finding, however, is the higher incidence of osteosarcoma relative to the general population in individuals with familial Li-Fraumeni syndrome (germline TP53
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