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1.
Front Microbiol ; 10: 1910, 2019.
Article in English | MEDLINE | ID: mdl-31543866

ABSTRACT

Using gamma-ray-induced mutagenesis, we have developed a mutant (named G2) of Trichoderma virens that produced two- to three-fold excesses of secondary metabolites, including viridin, viridiol, and some yet-to-be identified compounds. Consequently, this mutant had improved antibiosis against the oomycete test pathogen Pythium aphanidermatum. A transcriptome analysis of the mutant vis-à-vis the wild-type strain showed upregulation of several secondary-metabolism-related genes. In addition, many genes predicted to be involved in mycoparasitism and plant interactions were also upregulated. We used tamarind seeds as a mass multiplication medium in solid-state fermentation and, using talcum powder as a carrier, developed a novel seed dressing formulation. A comparative evaluation of the wild type and the mutant in greenhouse under high disease pressure (using the test pathogen Sclerotium rolfsii) revealed superiority of the mutant over wild type in protecting chickpea (Cicer arietinum) seeds and seedlings from infection. We then undertook extensive field evaluation (replicated micro-plot trials, on-farm demonstration trials, and large-scale trials in farmers' fields) of our mutant-based formulation (named TrichoBARC) for management of collar rot (S. rolfsii) in chickpea and lentil (Lens culinaris) over multiple locations in India. In certain experiments, other available formulations were included for comparison. This formulation consistently, over multiple locations and years, improved seed germination, reduced seedling mortality, and improved plant growth and yield. We also noticed growth promotion, improved pod bearing, and early flowering (7-10 days) in TrichoBARC-treated chickpea and lentil plants under field conditions. In toxicological studies in animal models, this formulation exhibited no toxicity to mammals, birds, or fish.

2.
Ann Oncol ; 28(9): 2119-2127, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28911066

ABSTRACT

BACKGROUND: Toxicity associated with chemotherapy is a major therapeutic challenge and is caused by chemotherapy-induced DNA damage and inflammation. We have recently reported that cell-free chromatin (cfCh) fragments released from dying cells can readily enter into healthy cells of the body to integrate into their genomes and induce DNA double-strand breaks, apoptosis and inflammation in them. We hypothesized that much of the toxicity of chemotherapy might be due to release of large quantities of cfCh from dying cells that could trigger an exaggerated DNA damage, apoptotic and inflammatory response in healthy cells over and above that caused by the drugs themselves. METHODS: We tested this hypothesis by administering cfCh neutralizing/degrading agents namely, anti-histone antibody complexed nanoparticles, DNase I and a novel DNA degrading agent-Resveratrol-Cu concurrently with five different chemotherapeutic agents to examine if chemotherapy-induced toxicity could be minimized. RESULTS: We observed (i) significant reduction in chemotherapy-induced surge of cfCh in blood; (ii) significant reduction in chemotherapy-induced surge of inflammatory cytokines CRP, IL-6, IFNγ and TNFα in blood; (iii) abolition of chemotherapy-induced tissue DNA damage (γH2AX), apoptosis (active caspase-3) and inflammation (NFκB and IL-6) in multiple organs and peripheral blood mononuclear cells; (iv) prevention of prolonged neutropenia following a single injection of adriamycin and (v) significant reduction in death following a lethal dose of adriamycin. CONCLUSION: Our results suggest that toxicity of chemotherapy is caused to a large extent by cfCh released from dying cells and can be prevented by concurrent treatment with cfCh neutralizing/degrading agents.


Subject(s)
Antineoplastic Agents/adverse effects , Chromatin/drug effects , Neoplasms/drug therapy , Animals , Apoptosis , Cell-Free System , Chromatin/metabolism , Cytokines/blood , DNA Damage , Humans , Inflammation Mediators/blood , Neoplasms/blood , Neoplasms/pathology
3.
Carbohydr Lett ; 4(2): 117-22, 2001.
Article in English | MEDLINE | ID: mdl-11506156

ABSTRACT

Several novel glycofuranoses disaccharides related to mycobacterial cell wall polysaccharides were synthesized regio- and stereoselectively using 2,3,5-tri-O-benzoyl-alpha-D-arabinofuranosyl trichloroacetimidate as a glycosyl donor.


Subject(s)
Disaccharides/chemistry , Disaccharides/chemical synthesis , Galactans/chemistry , Mycobacterium/chemistry , Acetamides , Carbohydrate Sequence , Chloroacetates , Glycosylation , Magnetic Resonance Spectroscopy , Molecular Structure , Polysaccharides, Bacterial/chemistry
4.
Development ; 128(1): 87-94, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11092814

ABSTRACT

Recent studies in Drosophila have shown that heparan sulfate proteoglycans (HSPGs) are required for Wingless (Wg/Wnt) signaling. In addition, genetic and phenotypic analyses have implicated the glypican gene dally in this process. Here, we report the identification of another Drosophila glypican gene, dally-like (dly) and show that it is also involved in Wg signaling. Inhibition of dly gene activity implicates a function for DLY in Wg reception and we show that overexpression of DLY leads to an accumulation of extracellular Wg. We propose that DLY plays a role in the extracellular distribution of Wg. Consistent with this model, a dramatic decrease of extracellular Wg was detected in clones of cells that are deficient in proper glycosaminoglycan biosynthesis. We conclude that HSPGs play an important role in organizing the extracellular distribution of Wg.


Subject(s)
Drosophila Proteins , Drosophila/physiology , Heparan Sulfate Proteoglycans/physiology , Proto-Oncogene Proteins/physiology , Signal Transduction , Amino Acid Sequence , Animals , Gene Expression Regulation , Genes, Insect , Molecular Sequence Data , Repressor Proteins/physiology , Wnt1 Protein
5.
Mech Dev ; 99(1-2): 199-202, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11091094

ABSTRACT

Proteoglycans, the molecules of extracellular matrix, carry a highly negative charge due to their glycosaminoglycan (GAG) chains and large volumes. They were considered to play a secondary role in activities like cell division, adhesion, blood coagulation, etc. until the importance of their sugar chains in the fibroblast growth factor (FGF) signalling was discovered (Science 252 (1991) 1705; Cell 64 (1991) 841). Studies of mutations in the genes sugarless(sgl) and sulfateless (sfl) have proved that the proteoglycans involved in Wg signalling contain heparan sulfate GAG chains (Development 124 (1997) 2623; Development 124 (1997) 3055; Development 124 (1997) 3565; Development 126 (1999) 3715). This has led to the attribution of specific functions to these molecules (J. Cell Biol. 148 (2000) 227). The Glypican family of heparan sulfate proteoglycans (HSPGs) is characterized by core proteins with conserved cysteine residues and attachment to the cell surface by a glycosylphosphatidyl inositol (GPI) anchor. This may lead to endocytic pathways that are different from other HSPGs, higher lateral mobility and possible apical localisation in a cell (Proc. Natl. Acad. Sci, USA 85 (1988) 9557). Variations in their HS contents may effect binding properties and localisation (J. Cell Biol. 124 (1994) 149; J. Cell Biol. 132 (1996) 487), thus specialising each member for a unique biological function. Glypicans play important roles in morphogenetic pathways, e.g. human glypican 3 (GPC3) is mutated in Simpson-Golabi-Behmel syndrome making an individual prone to tumours (Nat. Genet. 12 (1996) 241). Dally, the first Drosophila member of the family, is essential for the wingless and decapentaplegic signalling pathways (Development 121 (1995) 3687; Development 124 (1997) 4113). Here, we report a new Drosophila glypican, dally-like protein (dlp) with all the features of a glypican. Based on expression studies we report its colocalisation with Wg.


Subject(s)
Drosophila Proteins , Drosophila/embryology , Drosophila/genetics , Heparan Sulfate Proteoglycans/chemistry , Membrane Glycoproteins/metabolism , Proteoglycans/biosynthesis , Proteoglycans/genetics , Proteoglycans/metabolism , Proto-Oncogene Proteins/biosynthesis , Amino Acid Sequence , Animals , Blotting, Northern , Cloning, Molecular , Drosophila/metabolism , Embryo, Nonmammalian/metabolism , Female , Male , Models, Biological , Molecular Sequence Data , Phylogeny , RNA, Messenger/metabolism , Sequence Homology, Amino Acid , Time Factors , Wnt1 Protein
6.
Mech Dev ; 91(1-2): 393-7, 2000 Mar 01.
Article in English | MEDLINE | ID: mdl-10704872

ABSTRACT

We report the sequence and expression analysis of two new Drosophila members of the Semaphorin family. Both proteins show the presence of Semaphorin domains and transmembrane domains. Both genes are expressed maternally and in embryos, and reveal distinct expression patterns much earlier than the onset of neurogenesis. We also present an overview of the domain structure of all so far known semaphorins in Drosophila. Furthermore, we compared all Drosophila and C. elegans Semaphorins and discuss them in the light of their evolution.


Subject(s)
Cell Adhesion Molecules, Neuronal/genetics , Drosophila/embryology , Membrane Glycoproteins/genetics , Semaphorins , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , DNA, Complementary , Drosophila/genetics , Drosophila Proteins , Evolution, Molecular , Gene Expression , Membrane Glycoproteins/metabolism , Membrane Glycoproteins/physiology , Molecular Sequence Data , RNA, Messenger , Sequence Analysis, DNA , Sequence Homology, Amino Acid
7.
Phytochemistry ; 52(4): 675-9, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10570829

ABSTRACT

The structures of two novel trisaccharides viz. royleose and deniose isolated from Marsdenia roylei were elucidated with the help of modern physico-chemical techniques and chemical transformations. They were defined as O-beta-D-oleandropyranosyl-(1-->4)-O-beta- D-cymaropyranosyl-(1-->4)-beta-D-oleandropyranose and O-beta-D-oleandropyranosyl-(1-->4)-O-beta-D-digitoxopyranosyl++ +-(1-->4)- beta-D-oleandropyranose respectively. This is the first report on the isolation of trisaccharides of rare deoxy sugars in free state from nature.


Subject(s)
Plants, Medicinal/chemistry , Trisaccharides/chemistry , Trisaccharides/isolation & purification , Acetylation , Carbohydrate Conformation , Carbohydrate Sequence , Hydrolysis , Molecular Sequence Data , Nuclear Magnetic Resonance, Biomolecular , Spectrometry, Mass, Fast Atom Bombardment
8.
Phytochemistry ; 50(8): 1353-7, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10326255

ABSTRACT

Phytochemical analysis of dried twigs of Marsdenia roylei (family Asclepiadaceae) has resulted in the isolation of a trisaccharide, maryal, and a diglycoside, rolinose. Their structures were determined as O-beta-D-oleandropyranosyl-(1-->4)-O-beta-D-digitoxopyranosyl++ +-(1-->4)-D- cymaral and ethyl O-beta-D-oleandropyranosyl-(1-->4)-O-3-O-methyl-6-deoxy-beta-D- allopyranoside, respectively, by chemical degradation and spectroscopic methods.


Subject(s)
Disaccharides/chemistry , Plants/chemistry , Trisaccharides/chemistry , Carbohydrate Conformation , Carbohydrate Sequence , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Spectrometry, Mass, Fast Atom Bombardment
9.
J Cell Biol ; 145(1): 191-201, 1999 Apr 05.
Article in English | MEDLINE | ID: mdl-10189378

ABSTRACT

We report the molecular and functional characterization of a new alpha chain of laminin in Drosophila. The new laminin chain appears to be the Drosophila counterpart of both vertebrate alpha2 (also called merosin) and alpha1 chains, with a slightly higher degree of homology to alpha2, suggesting that this chain is an ancestral version of both alpha1 and alpha2 chains. During embryogenesis, the protein is associated with basement membranes of the digestive system and muscle attachment sites, and during larval stage it is found in a specific pattern in wing and eye discs. The gene is assigned to a locus called wing blister (wb), which is essential for embryonic viability. Embryonic phenotypes include twisted germbands and fewer pericardial cells, resulting in gaps in the presumptive heart and tracheal trunks, and myotubes detached from their target muscle attachment sites. Most phenotypes are in common with those observed in Drosophila laminin alpha3, 5 mutant embryos and many are in common with those observed in integrin mutations. Adult phenotypes show blisters in the wings in viable allelic combinations, similar to phenotypes observed in integrin genes. Mutation analysis in the eye demonstrates a function in rhabdomere organization. In summary, this new laminin alpha chain is essential for embryonic viability and is involved in processes requiring cell migration and cell adhesion.


Subject(s)
Drosophila Proteins , Drosophila melanogaster/genetics , Gene Expression Regulation, Developmental , Genes, Insect , Insect Proteins/physiology , Laminin/physiology , Protein Isoforms/physiology , Wings, Animal/embryology , Alleles , Amino Acid Sequence , Animals , Cell Adhesion/genetics , Cell Movement/genetics , Drosophila melanogaster/embryology , Drosophila melanogaster/growth & development , Embryo, Nonmammalian/abnormalities , Eye Abnormalities/genetics , Insect Proteins/genetics , Laminin/genetics , Larva , Molecular Sequence Data , Morphogenesis/genetics , Phenotype , Protein Isoforms/genetics , RNA, Messenger/analysis , Wings, Animal/abnormalities
12.
Carbohydr Res ; 216: 357-73, 1991 Sep 02.
Article in English | MEDLINE | ID: mdl-1797386

ABSTRACT

The tetrasaccharide hapten released from the glycopeptidolipid (GPL) antigen of Mycobacterium avium serovar 20 has been characterized as O-(2-O-methyl-alpha-D-rhamnopyranosyl)-(1----3)-O-(2-O-methyl-alpha-L- fucopyranosyl)-(1----3)-alpha-L-rhamnopyranosyl-(1----2)-6-deoxy-L-talos e. Syntheses are reported of allyl glycosides of the outer disaccharide unit of this hapten, O-(2-O-methyl-alpha-D-rhamnopyranosyl)-(1----3)-2-O-methyl-alpha-L-fu copyranose , and also of the outer di- and tri-saccharide units of the GPL antigen of M. avium serovar 14, O-(N-formyl-alpha-L-kansosaminyl)-(1----3)-2-O-methyl-alpha-D-rham nopyranose and O-(N-formyl-alpha-L-kansosaminyl)-(1----3)-O-(2-O-methyl-alpha-D- rhamnopyranosyl)-(1----3)-2-O-methyl-alpha-L-fucopyranose. The key steps in the latter synthesis involve the preparation of allyl 4-azido-4,6-dideoxy-3-C-methyl-2-O-methyl-alpha-L-mannopyranoside as a precursor for the N-formylkansosamine unit, followed sequentially by conversion into and use of a trichloroacetimidate as glycosyl donor for di- and tri-saccharide formation, O-deacylation, reduction, and N-formylation. The allyl glycosides, representative of the haptens from both serovars, have been converted into neoglycoproteins (NGPs) and their serological activities have been compared in the light of the structural relationship between them.


Subject(s)
Antigens, Bacterial/chemistry , Glycoconjugates/chemistry , Glycoconjugates/immunology , Mycobacterium avium Complex/immunology , Carbohydrate Sequence , Disaccharides/chemistry , Disaccharides/immunology , Glycoproteins/chemistry , Glycoproteins/immunology , Molecular Sequence Data , Molecular Structure , Mycobacterium avium Complex/classification , Serotyping , Trisaccharides/chemistry , Trisaccharides/immunology
13.
Carbohydr Res ; 216: 337-55, 1991 Sep 02.
Article in English | MEDLINE | ID: mdl-1724632

ABSTRACT

Neoglycoproteins bearing key glycosyl substituents of several glycopeptidolipid antigens of pathogenic Mycobacterium species have been synthesized. Allyl glycosides of the terminal 6-deoxyhexose-containing units of the antigens were prepared, with appropriate ether and ester substituents in place. Ozonolysis of the allyl glycosides was then followed by reductive coupling with epsilon-amino groups of lysine residues in bovine serum albumin, using sodium cyanoborohydride at pH 7.8. The resulting neoglycoproteins emulated the antigenicity of the native molecule in several serological tests.


Subject(s)
Antigens, Bacterial/chemistry , Glycoproteins/chemical synthesis , Glycoproteins/immunology , Glycosides/chemical synthesis , Carbohydrate Sequence , Epitopes/chemistry , Glycolipids/chemistry , Glycolipids/immunology , Glycoproteins/chemistry , Glycosides/chemistry , Molecular Sequence Data , Molecular Structure , Mycobacterium avium Complex/immunology
14.
J Nat Prod ; 50(4): 600-3, 1987.
Article in English | MEDLINE | ID: mdl-3430162

ABSTRACT

A new pregnane derivative designated as bregenin [1] has been isolated from the dried twigs of Sarcostemma brevistigma. Chemical and spectroscopic evidence is consistent with the structure 3 beta, 14 beta, 16 alpha, 17 beta tetrahydroxypregn-5-en-20-one for bregenin.


Subject(s)
Plants, Medicinal/analysis , Pregnanes/analysis , Chemical Phenomena , Chemistry , Magnetic Resonance Spectroscopy , Mass Spectrometry
15.
Arch Androl ; 4(4): 357-62, 1980 Jun.
Article in English | MEDLINE | ID: mdl-7416856

ABSTRACT

Higher incidence of prostate cancer among lead and cadmium smelter workers has been reported. Forty male rats were divided into four groups. Group I served as control; Group II was injected intraperitoneally, close to the site of the prostate, with 0.05 mg lead acetate; Group III was injected with 0.05 mg cadmium chloride; and Group IV was injected with a combination of 0.025 mg lead and 0.025 mg cadmium chloride. After daily injection for one month, lead and cadmium had a synergistic effect on testicular damage and prostatic cytology; although no tumor formation was observed in the prostate, there was replacement of columnar epithelium by squamous epithelium, suggestive of progressive, precancerous changes. There was an increase in incidence of stone formation in the kidney and urinary bladder.


Subject(s)
Cadmium/toxicity , Kidney/drug effects , Lead/toxicity , Prostate/drug effects , Testis/drug effects , Urinary Bladder/drug effects , Animals , Cadmium/blood , Carcinogens/pharmacology , Kidney Calculi/chemically induced , Lead/blood , Male , Organ Size , Rats , Urinary Bladder Calculi/chemically induced
16.
Invest Urol ; 17(4): 288-92, 1980 Jan.
Article in English | MEDLINE | ID: mdl-6766125

ABSTRACT

Human transitional cell carcinoma was successfully grown in short-term tissue culture in 17 of 29 specimens collected (58 per cent). Morphologic parameters of the explants were studied with light and transmission electron microscopy before and after incubation with either thiotepa or 5-fluorouracil. Thiotepa was found to produce marked acantholysis in 43 per cent of those studied. We postulate that thiotepa acts primarily through breakdown of cell adherence. Changes found with 5-fluorouracil were primarily confined to the nucleus.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Transitional Cell/ultrastructure , Urinary Bladder Neoplasms/ultrastructure , Cell Nucleolus/drug effects , Fluorouracil/pharmacology , Humans , In Vitro Techniques , Intercellular Junctions/drug effects , Microvilli/drug effects , Nuclear Envelope/drug effects , Thiotepa/pharmacology
17.
Res Commun Chem Pathol Pharmacol ; 20(2): 351-65, 1978 May.
Article in English | MEDLINE | ID: mdl-674820

ABSTRACT

Forty male rats were divided into four groups. Group I served as control. Group II received 1 mg. lead injected into the prostate; Group III received 1 mg. cadmium chloride; and Group IV received 0.5 mg. lead acetate and 0.5 mg. cadmium chloride. Results indicated that lead caused stone formation in the bladder and calcification of both bladder and prostate; cadmium caused reduction in size and weight of prostate, and histological observation showed marked atrophy of the gland, cuboidal epithelium, and squamous metaplasia in the acini of the prostate; there was no synergistic effect of lead acetate and cadmium chloride when combined at the level administered to Group IV.


Subject(s)
Cadmium/pharmacology , Lead/pharmacology , Prostate/drug effects , Animals , Body Weight/drug effects , Cadmium/blood , Calcium Chloride/pharmacology , Lead/blood , Male , Organ Size/drug effects , Prostate/anatomy & histology , Prostate/cytology , Rats , Testis/drug effects , Urinary Bladder/drug effects
18.
Neurol India ; 25(3): 193-4, 1977 Sep.
Article in English | MEDLINE | ID: mdl-613266
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