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R Geyer

Publications and source records attributed to R Geyer.

At least 55 records · Page 3Linked to original sources
PubMed1999

Isolation, characterization and immunolocalization of phosphorylcholine-substituted glycolipids in developmental stages of Caenorhabditis elegans.

Caenorhabditis elegans displays three neutral glycosphingolipids with structural homology to glycosphingolipids from the porcine nematode parasite, Ascaris suum. The present findings extend the degree of structural conservation between the two nematode species to glycosphingolipids with a phosphodiester substitution. Using a combination of hydrofluoric acid pretreatment, immunochemical characterization and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, three zwitterionic, phosphorylcholine-substituted glycosphingolipids could be identified in the neutral glycolipid fraction of C. elegans. The components were isolated as their zwitterionic, phosphorylcholine-substituted, pyridylaminated oligosaccharides by HPLC. Structural analysis was performed using hydrofluoric acid treatment, partial acid hydrolysis, methylation analysis, gas chromatography-mass spectrometry, cleavage with exoglycosidases and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Their chemical structures are proposed as: component Nz1, GalNAc(beta1-4)[phosphorylcholine]GlcNAc(beta1-3)Man(beta1-4)Glc-cera mide; component Nz2, Gal(alpha1-3)GalNAc(beta1-4)[phosphorylcholine]-GlcNAc(beta1-3)Man(be ta1-4)Glc-ceramide; and component Nz3, Gal(beta1-3)- Gal(alpha1-3)GalNAc(beta1-4)[phosphorylcholine]GlcNAc(beta1-3)Man(bet a1-4)Glc-ceramide. The oligosaccharide core is characteristic of the biosynthetic arthro-carbohydrate series of protostomial glycosphingolipids. The ceramide moiety was specified by a d17 : 1 sphingoid-base with iso-branching and anteiso-branching, and 2-hydroxy, saturated fatty acids as represented by docosanoic and tetracosanoic acids. Analysis of the spatial and temporal expression of the phosphorylcholine epitope, during embryonic and postembryonic development, showed it to be localized predominantly in seam cells and basement membranes, respectively. In early embryonic ontogenesis the phosphorylcholine epitope was only lipid bound, while in late embryonic and postembryonic development this epitope was both lipid bound and protein bound.

Animals↗
PubMed1999

Isolation and structural characterization of glycosphingolipids of in vitro propagated human umbilical vein endothelial cells.

To investigate in detail the expression of glycosphingolipids (GSLs) on endothelial cells, 4.85 x 10(9) human umbilical vein endothelial cells (HUVECs) were cultivated in a 2 l bioreactor using microcarriers as a support for anchorage dependent growing cells. Neutral GSLs and gangliosides were isolated and their structures were determined by TLC immunostaining, fast atom bombardment-mass spectrometry (FAB-MS) of the native GSLs, and gas chromatography-electron impact mass spectrometry (GC-EIMS) of partially methylated alditol acetates. GbOse4Cer, GbOse3Cer, and LacCer, all carrying mainly C24- and C16-fatty acid beside C18-sphingosine, were detected as the major neutral GSLs (36%, 23%, and 15% of the total orcinol stain, respectively); GlcCer, nLcOse4Cer, and nLcOse6Cer were expressed to substantial minor amounts (9%, 12%, and 5% of the total orcinol stain, respectively). TLC immunostaining revealed the presence of lipid bound Lewisx antigen, whereas the isomeric Lewisa structure was detectable only in very low quantities. GM3(Neu5Ac) with C18-sphingosine was the major ganglioside constituting about 90% of the whole ganglioside fraction. The fatty acid composition was determined by GC-MS of fatty acid methyl esters, indicating the predominance of C24- and C16-substituted GM3(Neu5Ac), followed by C18- and C22-substituted species. Terminally alpha2-3 sialylated neolacto-series ganglioside IV3Neu5Ac-nLcOse4Cer was the second most abundant ganglioside in HUVECs (8% of the total resorcinol stain), and IV6Neu5Ac-nLcOse4Cer and VI3Neu5Ac-nLcOse6Cer (together less than 2% of total resorcinol stain) were found in minor quantities. Lipid bound sialyl Lewisx antigen with poly-N-acetyllactosaminyl chains, and traces of gangliotetraose-type gangliosides GM1 and GD1a were identified by TLC immunostaining. The expression of dominant neutral GSLs LacCer, GbOse3Cer, and GbOse4Cer, and of ganglioside GM3(Neu5Ac) was assayed by indirect immunofluorescence microscopy of cell layers grown in chamber slides, each showing different plasma membrane and subcellular distribution patterns. The complete structural characterization of GSLs from HUVECs contributes to our understanding about their functional role, not only of the carbohydrate but also of the lipid moiety, as receptors for bacterial toxins, as cell surface antigens of cellular interaction and as receptors for blood components and macromolecules of the extracellular matrix.

Bioreactors↗
PubMed1999

Characterization of human vascular endothelial cadherin glycans.

The glycosylation pattern of human vascular endothelial cadherin (VE-cadherin), purified from cultured human umbilical cord vein endothelial cells, was analyzed. VE-cadherin was metabolically radiolabeled with d-[6-(3)H]glucosamine, isolated by immunoprecipitation, purified by SDS-PAGE and in-gel digested with endoproteinase Asp N. Oligosaccharides were sequentially released from resulting glycopeptides and analyzed by chromatographic profiling. The results revealed that VE-cadherin carries predominantly sialylated diantennary and hybrid-type glycans in addition to some triantennary and high mannose-type species. Highly branched, tetraantennary oligosaccharides were found in trace amounts only. Immunohistochemical labeling of VE-cadherin and sialic acids displayed a codistribution along the intercellular junctions in endothelial cells of human umbilical arteries, veins, and cultured endothelial monolayers. Ca(2+)-depletion, performed on cultured endothelial cells, resulted in a reversible complete disappearance of VE-cadherin and of almost all sialic acid staining from the junctions. Sialidase treatment of whole cells caused a change of VE-cadherin immunofluorescence from a continuous and netlike superstructural organization to a scattered inconsistent one. Hence, cell surface sialic acids might play a role in VE-cadherin organization.

Actins↗
PubMed1998

Treatment of diencephalic syndrome with chemotherapy: growth, tumor response, and long term control.

BACKGROUND: The diencephalic syndrome (DS), which is manifested by progressive emaciation and failure to thrive in an apparently alert, cheerful infant, usually is due to a low grade hypothalamic glioma. Treatment with aggressive surgery and/or radiotherapy is variably successful in controlling disease and may result in severe neurologic sequelae. Chemotherapy recently has been shown to be effective in patients with low grade gliomas of childhood, but it is used infrequently in those with DS. METHODS: The authors evaluated the efficacy of a regimen of carboplatin and vincristine on improving weight, causing tumor shrinkage, and delaying the need for alternative therapies in seven children (ages 9-20 months; median age, 11 months) with DS. Five patients weighed less than the 5th percentile for their age at the start of the study, one weighed within the 10th percentile, and one weighed within the 25th percentile. RESULTS: At follow-up (range, 6-54 months; median, 28 months), the patients' weights had increased by 66-95% (median, 80%). On magnetic resonance imaging, four patients had a >50% reduction in tumor mass, one had a 25-50% reduction, and two had stable disease. In those patients with radiographic response to treatment, weight gain was accomplished with oral feedings in four of five patients, whereas those with stable disease required nasogastric, nasojejunal, or gastrostomy tube supplementation to maintain weight. Disease progression occurred at a median of 24 months after initiation of chemotherapy, and two patients remained free of progressive disease at last follow-up. Five patients were alive a median of 59 months from diagnosis. The need for radiation or other therapies was delayed in six of seven children. Therapy was tolerated without significant toxicities. CONCLUSION: The authors conclude that treatment of DS with a carboplatin and vincristine regimen results in demonstrable weight gain, may result in tumor shrinkage, and in some cases, significantly delays the need for alternative therapies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Structural elucidation and monokine-inducing activity of two biologically active zwitterionic glycosphingolipids derived from the porcine parasitic nematode Ascaris suum.

The isolated neutral glycosphingolipid fraction from the pig parasitic nematode, Ascaris suum, was fractionated by silica gel chromatography to yield a neutral and a zwitterionic glycosphingolipid fraction, the latter of which mainly contained two zwitterionic glycosphingolipids termed components A and C. Preliminary chemical characterization with hydrofluoric acid treatment and immunochemical characterization with a phosphocholine-specific monoclonal antibody indicated that both components contained phosphodiester substitutions: phosphocholine for component A, and phosphocholine and phosphoethanolamine for component C. Both components were biologically active in inducing human peripheral blood mononuclear cells to release the inflammatory monokines tumor necrosis factor alpha, interleukin 1, and interleukin 6. Component A was the more bioactive molecule, and its biological activity was abolished on removal of the phosphocholine substituent by hydrofluoric acid. The glycosphingolipid components were structurally analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, liquid secondary ion mass spectrometry, methylation analysis, 1H NMR spectroscopy, exoglycosidase cleavage, and ceramide analysis. Their chemical structures were elucidated to be (see Structure I below), [structure: see text] The carbohydrate moiety oligosaccharide core was characterized as belonging to the arthro series of protostomial glycosphingolipids. The ceramide moiety was distinguished by (R)-2-hydroxytetracosanoic acid as the dominant fatty acid species and by the C17 iso-branched sphingosine and sphinganine bases, 15-methylhexadecasphing-4-enine and 15-methylhexadecasphinganine, respectively.

Animals↗
PubMed1998

Juvenile female Litomosoides sigmodontis produce an excretory/secretory antigen (Juv-p120) highly modified with dimethylaminoethanol.

A 120 kDa antigen produced by juvenile female Litomosoides sigmodontis (Juv-p120) was isolated and purified. The amino acid composition of the molecule was determined. Juv-p120 was shown to be highly modified with N,N-dimethyl-aminoethanol (28.4 mol%). Treatment of Juv-p120 with potassium hydroxide (beta-elimination) or with sodium m-periodate leads to the destruction of epitopes recognized by antibodies immune affinity-purified with isolated Juv-p120. Juvenile L. sigmodontis were shown to release Juv-p120 into the pleural cavity of infected Mastomys coucha before the onset of patency.

Amidohydrolases↗
PubMed1998

Structural analysis and immunohistochemical localization of two acidic glycosphingolipids from the porcine, parasitic nematode, Ascaris suum.

The acidic glycolipid fraction (AF) of the porcine, parasitic nematode, Ascaris suum , consisted of two subfractions. The major component AF II reacted with orcinol-sulfuric acid and molybdate, while the minor component AF I gave a positive reaction with azure-A, a cationic dye specific for sulfatides. Sugar constituent analysis, methanolysis, methylation analysis, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, liquid secondary-ion mass spectrometry, and gas-liquid chromatography/mass spectrometry specified AF II to be an unusual phosphoinositolglycosphingolipid (Galalpha1-Ins-P-1ceramide) and the minor component AF I to be a 3-sulfogalactosylcerebroside (HSO3-3Galss1-1ceramide). The ceramide moiety of both components consisted of lignoceric (C24:0) and cerebronic (C24h:0) acids and mainly C17 iso-branched sphingosine. Immunohistochemical localization studies of the glycolipid-bound antigenic determinants with a polyclonal antiserum against AF II and an anti-sulfatide monoclonal antibody against AF I revealed the presence of the AF II-epitope in the intestine, whereas the AF I-epitope was found in the hypodermis, contractile zone of somatic muscle cells and the external musculature of the uterus. To our knowledge, this is the first report of the presence of a sulfatide in an invertebrate.

Animals↗
PubMed1998

Structure and glycosylation patterns of surface proteins from woodchuck hepatitis virus.

Woodchucks chronically infected with woodchuck hepatitis virus (WHV) are a valuable model for human hepatitis B virus (HBV) in studies of pathogenesis, immunity, and antiviral therapy. For this reason, substantial efforts to characterize both the similarities and the differences between HBV and WHV are being made. The structure of the WHV surface proteins (WHs proteins) has not yet been adequately elucidated. The bands that would be expected for glycosylated and nonglycosylated small (S) WHs protein are found by sodium dodecyl sulfate gel electrophoresis of purified WHs protein, but the bands corresponding to the middle (M) and large (L) WHs proteins of HBV are not seen at the expected sizes, even though the sequences of the WHV and HBV surface protein genes are 60% homologous. By amino-terminal sequencing we have identified two bands at 41 and 45 kDa as the MWHs proteins, 8 kDa larger than expected. We have also confirmed that two bands at 24 and 27 kDa are SWHs proteins. A protein of 49 kDa was blocked at the N terminus, which using immunoblotting with an antiserum against WHV pre-S1 (positions 126 to 146) was identified, together with a part of the 45-kDa protein, as glycosylated and nonglycosylated LWHs protein of the expected size. Sialidase and O-glycosidase digestion showed that the larger size of MWHs protein results from the presence of O glycoside groups which are probably in the pre-S2 domain of MWHs protein. Since the pre-S2 domains of HBV and WHV have similar numbers of potential O glycosylation sites, it appears to be likely that the glycosyltransferases act differently on the viral proteins in woodchucks and humans.

Amino Acid Sequence↗
PubMed1998

Strategies for glycoconjugate analysis.

Glycoconjugates such as glycoproteins and glycosphingolipids exhibit multiple functions in biological systems. A correlation of functional features with defined structural parameters, however, presupposes detailed information on the glycoconjugates' carbohydrate moieties including the type of linkage of the oligosaccharide chain(s), monosaccharide composition as well as sequence, linkage positions and anomeric configurations of individual sugar monomers. Chemical and biochemical analyses are often impeded by the limited amounts of sample available and the vast structural heterogeneity of glycoconjugate glycans, thus requiring highly sensitive and efficient methods for detection, separation and structural elucidation of these carbohydrates. The aim of the article is to present suitable strategies for structural characterization of glycoconjugate glycans and to briefly review some of the techniques commonly used in this field.

Carbohydrates↗
PubMed1997

Structural analysis of neutral glycosphingolipids from Ascaris suum adults (Nematoda:Ascaridida).

The neutral glycosphingolipid fraction from adults of the pig parasitic nematode, Ascaris suum, was resolved into four components on thin-layer chromatography. The high-performance liquid chromatography-isolated components were structurally analysed by: methylation analysis; exoglycosidase cleavage; gas-liquid chromatography/mass spectrometry; liquid secondary-ion mass spectrometry; and, in particular, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Their chemical structures were determined as: Glc(beta 1-1)ceramide, Man(beta 1-4)Glc(beta 1-1)ceramide, GlcNAc(beta 1-3)Man(beta 1-4)Glc(beta 1-1)ceramide and Gal(alpha 1-3)GalNAc(beta 1-4)GlcNAc(beta 1-3)Man(beta 1-4)Glc(beta 1-1)ceramide; and were characterized as belonging to the arthro-series of protostomial glycosphingolipids. No glycosphingolipid component corresponding to ceramide tetrasaccharide was detected during these analyses. The ceramide composition of the parent glycosphingolipids was dominated by the 2-(R)-hydroxy C24:0 fatty acid, cerebronic acid, and C17 sphingoid-bases: 15-methylhexadecasphing-4-enine and 15-methylhexadecaphinganine in approximately equal proportions. The component ceramide monohexoside was characterized by an additional 15-methylhexadecaphytosphingosine.

Animals↗
PubMed1997

Host-cell-specific glycosylation of HIV-2 envelope glycoprotein.

Neutral complex-type N-glycans of the envelope glycoprotein 120 of HIV-2, propagated in different host cells, display cell-type specific variations. In order to identify typical structural elements, glycans were analysed by gel filtration, by enzymic sequencing and, in part, by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The characteristic substituents of di- tri- and tetraantennary carbohydrate units thus observed include N-acetyllactosamine repeats, bisecting N-acetylglucosamine and fucose linked to the chitobiose core as well as to N-acetyllactosamine antennae. Each glycoprotein preparation displayed a characteristic set of glycoforms.

Carbohydrate Sequence↗
PubMed1997

Isolation and structural analysis of three neutral glycosphingolipids from a mixed population of Caenorhabditis elegans (Nematoda:Rhabditida).

The free-living nematode, Caenorhabditis elegans, has been proposed and analyzed as a prototypic model for parasitic nematodes. In order to study whether there is a structural basis for the proposed analogy with respect to nematode glycoconjugates, we have analyzed Caenorhabditis elegans glycosphingolipids. Three, simple neutral glycosphingolipid components of the neutral glycolipid fraction were isolated by high-performance liquid chromatography. Structural analysis was performed by methylation analysis, exoglycosidase cleavage, matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry, and ceramide analysis. The chemical structures have been determined as Glc beta 1Cer, Man beta 4Glc beta 1Cer and GlcNAc beta 3Man beta 4Glc beta 1Cer; that are characterized as belonging to the arthroseries of protostomial glycosphingolipids. The ceramide moiety of the parent glycosphingolipid-ceramide mono-hexoside was dominated by 2-hydroxy fatty acids, and a d17:1 spingoid-base with an iso- or anteiso-branched chain. The chemical composition of the three glycosphingolipids from Caenorhabditis elegans displayed close structural coincidence with the equivalent structures from the porcine parasitic nematode, Ascaris suum (G.Lochnit, R.D. Dennis, U.Zähringer, and R.Geyer, Glycoconjugate J., 1997), in support of this organism as a prototypic glycosphingolipid model for parasitic nematodes.

Animals↗
PubMed1997

Carboplatin and vincristine chemotherapy for children with newly diagnosed progressive low-grade gliomas.

The optimum treatment of nonresectable low-grade gliomas of childhood remains undecided. There has been increased interest in the use of chemotherapy for young children, but little information concerning the long-term efficacy of such treatment. Seventy-eight children with a mean age of 3 years (range 3 months-16 years) who had newly diagnosed, progressive low-grade gliomas were treated with combined carboplatin and vincristine chemotherapy. The patients were followed for a median of 30 months from diagnosis, with 31 patients followed for more than 3 years. Fifty-eight children had diencephalic tumors, 12 had brainstem gliomas, and three had diffuse leptomeningeal gliomas. Forty-four (56%) of 78 patients showed an objective response to treatment. Progression-free survival rates were 75 +/- 6% at 2 years and 68 +/- 7% at 3 years. There was no statistical difference in progression-free survival rates between children with neurofibromatosis Type 1 and those without the disease (2-year, progression-free survival 79 +/- 11% vs. 75 +/- 6%, respectively). The histological subtype of the tumor, its location, and its maximum response to chemotherapy did not have an impact on the duration of disease control. The only significant prognostic factor was age: children 5 years old or younger at the time of treatment had a 3-year progression-free survival rate of 74 +/- 7% compared with a rate of 39 +/- 21% in older children (p < 0.01). Treatment with carboplatin and vincristine is effective, especially in younger children, in controlling newly diagnosed progressive low-grade gliomas.

Adolescent↗
PubMed1997

Nursing research 'down under'.

1. The major constraints preventing psychiatric nurses from conducting research are lack of time and knowledge. 2. Nurses can be motivated to explore the possibility of conducting research without having necessary skills or knowledge to start. 3. The nursing profession must face its responsibility to support and nurture nurses' interests in conducting and using research.

Adult↗
PubMed1996

Glycosyl-phosphatidylinositols of Trypanosoma congolense: two common precursors but a new protein-anchor.

The parasitic protozoan Trypanosoma congolense exhibits a dense surface coat which is pivotal for immunoevasion of the parasite. This dense surface coat is made of a single protein species, the variant surface glycoprotein, which is present in a high copy number. The protein is anchored to the plasma membrane by a glycosyl-phosphatidylinositol membrane anchor. A detailed study of the structure of T. congolense strain 423 (clone BENat 1.3) variant surface glycoprotein glycosyl-phosphatidylinositol membrane anchor was performed. Radioactively labelled core-glycan prepared by dephosphorylation, deamination and reduction was analysed by high-pH anion-exchange chromatography, size-exclusion and lectin affinity chromatography. Additionally the glycosyl-phosphatidylinositol membrane anchor core-glycan was purified from a bulk preparation of variant surface glycoprotein and subjected to mass spectrometry and methylation analysis. Using these methods we could identify a novel galactose-beta 1,6-N-acetyl-glucosamine-beta 1,4-branch modifying the mannose adjacent to the glucosamine of the mannose-alpha 1,2-mannose-alpha 1,6-mannose-alpha 1,4-glucosamine core-glycan of the variant surface glycoprotein glycosyl-phosphatidylinositol membrane anchor. Furthermore the biosynthetic pathway leading to this novel structure was investigated. Two putative glycosyl-phosphatidylinositol anchor precursors were identified having structures identical to the previously characterized Trypanosoma brucei brucei glycolipids P2 and P3 (also designated glycolipid A and C) consistent with a trimannosyl core and a dimyristoyl-glycerol. Both glycosyl-phosphatidylinositol anchor precursors of T. congolense do not possess the side-branch modification found on the mature protein membrane anchor, implying that the sugar side-chain is added to the anchor during its passage through the Golgi-apparatus.

Animals↗
PubMed1996

Glycosylation of recombinant ancrod from Agkistrodon rhodostoma after expression in mouse epithelial cells.

The thrombin-like serine protease ancrod from the Malayan pit viper Agkistrodon rhodostoma was expressed in mouse epithelial cells (C127). Oligosaccharide constituents were liberated from tryptic glycopeptides by treatment with peptide-N4-(N-acetyl-beta-glucosaminyl) asparagine amidase F. Neutral oligosaccharide alditols obtained after reduction and enzymic desialylation were separated by two-dimensional HPLC and characterized by methylation analysis, liquid secondary-ion mass spectrometry, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and sequential degradation with exoglycosidases. In contrast to natural ancrod, the recombinant glycoprotein carries exclusively diantennary, triantennary and tetraantennary N-glycans with Gal beta 4 GlcNAc beta (type-2) antennae which were, in part, further substituted by host-cell-specific structural elements such as Gal alpha 3 residues or N-acetyllactosamine repeats. As a characteristic feature, a substantial proportion of the oligosaccharides bears a GalNAc beta 4Glc-NAc antenna. Studies at the level of individual N-glycosylation sites demonstrated that glycans with N, N'-diacetyllactosediamine units are not specifically attached but occur at all sites in varying amounts. Hence, the putative recognition signal (Pro70-Lys-Lys) for glycoprotein hormone N-acetylgalactosaminyltransferase, present in this glycoprotein in close proximity to Asn79, does not convey site-specific transfer of GalNAc residues in these cells.

Agkistrodon↗
PubMed1996

Elongation of the N-glycans of fowl plague virus hemagglutinin expressed in Spodoptera frugiperda (Sf9) cells by coexpression of human beta 1,2-N-acetylglucosaminyltransferase I.

Spodoptera frugiperda (Sf9)-cells differ markedly in their protein glycosylation capacities from vertebrate cells in that they are not able to generate complex type oligosaccharide side chains. In order to improve the oligosaccharide processing properties of these cells we have used baculovirus vectors for expression of human (beta 1,2-N-acetylglucosaminyltransferase I (hGNT-I), the enzyme catalysing the crucial step in the pathway leading to complex type N-glycans in vertebrate cells. One vector (Bac/GNT) was designed to express unmodified GNT-I protein, the second vector (Bac/tagGNT) to express GNT-I protein with a tag epitope fused to its N-terminus. In Sf9-cells infected with Bac/tagGNT-virus a protein of about 50 kDa representing hGNT-I was detected with an antiserum directed against the tag epitope. HGNT-I activity was increased at least threefold in lysates of infected cells when N-acetylglucosamine (GlcNAc)-free ovalbumine was used as substrate. To monitor hGNT-I activity in intact Sf9-cells, the glycosylation of coexpressed fowl plague virus hemagglutinin (HA) was investigated employing a galactosylation assay and chromatographic analysis of isolated HA N-glycans. Coexpression of hGNT-I resulted in an at least fourfold increase of HA carrying terminal GlcNAc-residues. The only structure detectable in this fraction was GlcNAcMan3GlcNAc2. These results show that hGNT-I is functionally active in Sf9-cells and that the N-glycans of proteins expressed in the baculovirus/insect cell system are elongated by coexpression of glycosyltransferases of vertebrate origin. Complete complex type oligosaccharide side chains were not observed when hGNT-I was overexpressed, thus supporting the concept that Sf9-cells do not contain glycosyltransferases acting after hGNT-I.

Animals↗