| 748561 |
Impairments of glycogen and drug metabolisms by chloropeptide, a hepatotoxic mycotoxin of Penicillium islandicum sopp |
10.2131/jts.3.11. |
J Toxicol Sci |
Impairments of glycogen and drug metabolisms by chloropeptide, a hepatotoxic mycotoxin of Penicillium islandicum sopp
Abstract
- Administration of chloropeptide, a hepatotoxic cyclic pentapeptide of Penicillium islandicum Sopp, caused a marked decline in the hepatic glycogen synthetase activity with concomitant increase in NADP-dependent G-6-P dehydrogenase activity. The microsomalmixed function oxygenases were also reduced in the liver of rats following chloropeptide treatment.
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| 756601 |
Oxytocic activity of desamino-oxytocin (Sandopart). Personal clinical experience |
None |
Riv Ital Ginecol |
Oxytocic activity of desamino-oxytocin (Sandopart). Personal clinical experience
Abstract
|
| 816652 |
The structure of mycosubtilin, an antibiotic isolated from Bacillus subtilis (author's transl) |
10.1111/j.1432-1033.1976.tb10240.x. |
Eur J Biochem |
The structure of mycosubtilin, an antibiotic isolated from Bacillus subtilis (author's transl)
Abstract
- Mycosubtilin, an antifungal agent isolated from Bacillus subtilis is a mixture of homologous lipopeptides essentially C54H83N14O16 and C55H85N15O16. The differences in their structures was found in the lipid moiety which contains several beta-amino acids; the structure of these beta-amino acids was demonstrated by combined gas chromatography-mass spectrometry of the N-trifluoroacetyl n-butyl esters; a strong peak at m/e = 240 indicates a beta-amino group. The comparison of the derivatives of natural amino acids with synthetic 3-aminohexadecanoic and 3-aminoheptadecanoic acids indicates that natural beta-amino acids are a mixture of 3-amino-14-methylpentadecanoic acid (35%), 3-amino-14-methylhexadecanoic acid (59%), 3-aminohexadecanoic acid (6%) and a trace of C18 beta-amino acid. The peptide moiety contains 8 moles of amino acids, two of D-aspargine, two of L-asparagine, and one of L-glutamine, L-proline, D-serine and D-tyrosine. The peptide sequence was determinated by partial acid hydrolysis of mycosubtilin and isolation and structural determination of the peptides from the hydrolysates. Four liposoluble peptides and four hydrosoluble peptides were studied. The results gave the cyclic structure shown on Formula 1 for mycosubtilin.
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| 863789 |
Studies on aculeacin. II. Isolation and characterization of aculeacins B, C, D, E, F and G |
10.7164/antibiotics.30.303. |
J Antibiot (Tokyo) |
Studies on aculeacin. II. Isolation and characterization of aculeacins B, C, D, E, F and G
Abstract
- Six new antibiotics were isolated as the minor components related to aculeacin A from the culture broth of Aspergillus aculeatus M-4214 and named as aculeacins B, C, D, E, F and G. Their physico-chemical properties were analogous to those of aculeacin A and they showed significant activity against fungi. All of the minor components liberated palmitic acid on alkaline hydrolysis. Amino acid analysis showed that threonine and hydroxyproline are common constituents of aculeacins.
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| 873923 |
Primary structure of human prethrombin 2 and alpha-thrombin. |
10.1016/s0021-9258(17)40144-x |
J. Biol. Chem. |
Primary structure of human prethrombin 2 and alpha-thrombin.
Abstract
|
| 931364 |
Mechanism of action of EM 49, membrane-active peptide antibiotic |
10.1128/AAC.12.6.665. |
Antimicrob Agents Chemother |
Mechanism of action of EM 49, membrane-active peptide antibiotic
Abstract
- EM 49 (recently renamed octapeptin) is a membrane-active peptide antibiotic that has been reported to affect the structure of bacterial membranes (K. S. Rosenthal, P. E. Swanson, and D. R. Storm, Biochemistry 15:5783-5792, 1976). In this study, it is shown that the effects of EM 49 on bacterial metabolism are similar to those of uncouplers of oxidative phosphorylation. EM 49 stimulated bacterial respiration within a narrow concentration range corresponding to minimum inhibitory concentrations and inhibited respiration at concentrations comparable to minimum biocidal concentrations. In addition, the peptide increased membrane proton permeability and lowered the adenosine 5'-triphosphate pool size. Parallel studies done with the related antibiotic polymyxin B demonstrated that the two peptides differed considerably in their effects on bacterial respiration. In contrast to EM 49, polymyxin B did not stimulate respiration at any concentration. It is proposed that the primary action of EM 49 is to disrupt the selective ion permeability of the cytoplasmic membrane, thereby relaxing the membrane potential."
|
| 950660 |
Biological activity of C-terminal partial sequences of substance P |
10.1021/jm00228a028. |
J Med Chem |
Biological activity of C-terminal partial sequences of substance P
Abstract
- Substance P (Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2) and the C-terminal partial sequences down to the tripeptide were synthesized by a solid-phase method. These peptides were assayed for vasodilator, spasmogenic, and venoconstrictor properties using three preparations, viz. the hind limb blood flow of the dog, isolated guinea pig ileum, and the isolated rabbit ear vein. The tripeptide and tetrapeptide possessed weak vasodilator properties only but no activity was detected on the other less sensitive preparations. The pentapeptide produced appreciable spasmogenic and vasoactive effects. Sequences of six or more C-terminal amino acids were able to elicity activity at comparable doses to that of the parent endecapeptide; however, the activity did not increase regularly with the chain length. In each assay preparation the octapeptide was the most potent peptide. It was twice as potent as substance P on a molar basis in the guinea pig ileum but the enhancement of activity beyond that of substance P was less pronounced in the vascular preparations.
|
| 1152307 |
Studies on pharmacological and biochemical properties of deamino-dicarba-GLY-7-oxytocin (Y-5350) |
10.1254/jjp.25.15. |
Jpn J Pharmacol |
Studies on pharmacological and biochemical properties of deamino-dicarba-GLY-7-oxytocin (Y-5350)
Abstract
- Pharmacological and biochemical properties were investigated on deamino-dicarba-Gly-7-oxytocin (Y-5350). This is a newly developed compound, in which the disulfide bond and Pro-7 of deamino-oxytocin are substituted by an ethylene linkage and glycine respectively. Bioassayed Y-5350 exhibited 202.6 u/mg of oxytocic activity, 4.6 u/mg of avian depressor activity, 441.2 u/mg of rat milk-ejecting activity and 0.02 u/mg of rat antidiuretic activity, however, adepressor activity was also evident in rats. In particular, the diuration of antidiuretic activity was short. Moreover, the oxytocic activity in pregnant rats and rabbits was weak in comparison with oxytocin. Cumulative dose-response studies were carried out on the isolated rat uterus using van Dyke-Hasting solution. The intrinsic activity was the same level as that of oxytocin, and the pD2 value was 8.62. Oxytocic activity was much enhanced by the existence of 0.5 or 2mM magnesium ion in vitro. However, the agreement between in vivo and in vitro oxytocic activity was not complete when assay was carried out in the prescence of 2 mM magnesium ion. Oxytocin was inactivated by the serum of pregnant women. In the experiment using rats, oxytocin was also destroyed by the extracts of uterus, kidney and liver. In contrast, Y-5350 was not destroyed by any of the enzyme solutions mentioned above.
|
| 1152799 |
Endoscopic transpapillary cholangiography (author's transl) |
None |
Med Klin |
Endoscopic transpapillary cholangiography (author's transl)
Abstract
- Endoscopic transpapillary Cholangiography is able to give valuable informations for indication and operative procedure in biliary diseases especially in obstructive jaundice. Indication for "blind" explorative laparotomy seems to become more rare as well as necessity for clearing situations of biliary tract by surgical preparation or X-ray-examinations as usually performed. If one is well trained in technical procedures and in interpretation of radiologic findings, very helpful diagnostic hints can be presented. In opposition to retrograde pancreaticography, endoscopic examination of the biliary tract can be propagated with more enthusism.
|
| 1281482 |
The cyclic peptide synthetase catalyzing HC-toxin production in the filamentous fungus Cochliobolus carbonum is encoded by a 15.7-kilobase open reading frame |
None |
J Biol Chem |
The cyclic peptide synthetase catalyzing HC-toxin production in the filamentous fungus Cochliobolus carbonum is encoded by a 15.7-kilobase open reading frame
Abstract
- Race 1 of Cochliobolus carbonum, a fungal plant pathogen, owes its exceptional virulence on certain genotypes of maize to the production of HC-toxin, a cyclic tetrapeptide. Production of HC-toxin is controlled by a single known gene, TOX2. Race 1, but not races that do not make HC-toxin, contains two copies of a 22-kilobase (kb) region of chromosomal DNA that is required for HC-toxin biosynthesis and hence virulence. We have sequenced this 22-kb region and here show that it contains an open reading frame of 15.7 kb that encodes a multifunctional cyclic peptide synthetase of potential M(r)574,620. This gene, called HTS1, apparently contains no introns. The predicted gene product, HC-toxin synthetase (HTS), contains four amino acid-binding (adenylate-forming) domains that are highly similar to those found in other cyclic peptide synthetases and other adenylate-binding enzymes. The DNA sequence encodes tryptic peptides derived from two HC-toxin biosynthetic enzymes, HC-toxin synthetase 1 (HTS-1) and HC-toxin synthetase 2 (HTS-2), indicating that these two enzymes exist in vivo as part of a single polypeptide. Consistent with this, in some enzyme preparations antibodies against the enzyme HTS-2, which was originally purified as a protein with a subunit M(r) of 160,000, recognize a protein with an estimated subunit M(r) greater than 480,000.
|
| 1285411 |
Diet-induced dermatitis response of hairless rats to systemic treatment with cyclosporin A (Sandimmun), cyclosporin H and FK506 |
10.1111/j.1600-0625.1992.tb00189.x. |
Exp Dermatol |
Diet-induced dermatitis response of hairless rats to systemic treatment with cyclosporin A (Sandimmun), cyclosporin H and FK506
Abstract
- Weaned hairless rats were fed a diet deficient in fat, magnesium and folacin. After approximately 1 week, an erythematous dermatitis developed which was associated with extreme generalized pruritus. Scratching led to excoriations and hemorrhagic crusting. The acute stage (pruritic rash) resolved after several days and was followed by sporadic non-itching relapses. Subsequent to the onset of symptoms, rats were treated orally, once daily for 3 days with CyA, CyH or FK506. The immunosuppressants CyA and FK506 caused a dose-dependent inhibition of symptoms in contrast to CyH. The immediate clinical response was associated with changes in blood histamine, white blood cell counts and histological parameters. Since CyH is known to lack immunosuppressive activity, these results may indicate that the cutaneous changes induced by the nutritional deficiency are associated with immunological abnormalities. The results may also indicate mechanisms influenced by CyA and FK506 but not by CyH; for example, release of chemical mediators from inflammatory cells.
|
| 1286690 |
The central mechanism of the immunomodulating action of vasopressin and its structural analogs |
None |
Fiziol Zh (1978) |
The central mechanism of the immunomodulating action of vasopressin and its structural analogs
Abstract
- It is shown that the effect of neuropeptides depends on the dose and their structure. Considerable immunostimulation is observed after administration of 8-argininevasopressin and des-9-glucine-8-argininevasopressin as against the control. This stimulation is prevented by the preliminary heloperidol blockade of dopaminergic receptors, i.e. it is dopamine-dependent. At the same time, injection of tetrapeptide vesopressin-(2-5) induces deep immunosuppression in all the applied doses. The peptide immunosuppression is shown to be a result of interaction with another neuromediator (serotoninergic); it has no effect under preliminary cuproheptadine blockade of C-2 serotonin postsynaptic receptors. The immunomodulating effect of the neuropeptides studied is central one and is realized via the hypothalamus-hypophysis complex.
|
| 1287674 |
Natural products which interact with tubulin in the vinca domain: maytansine, rhizoxin, phomopsin A, dolastatins 10 and 15 and halichondrin B |
10.1016/0163-7258(92)90028-x. |
Pharmacol Ther |
Natural products which interact with tubulin in the vinca domain: maytansine, rhizoxin, phomopsin A, dolastatins 10 and 15 and halichondrin B
Abstract
- This paper summarizes published data on the interactions of tubulin with antimitotic compounds that inhibit the binding of vinca alkaloids to the protein. These are all relatively complex natural products isolated from higher plants, fungi and marine invertebrate animals. These agents are maytansine, rhizoxin, phomopsin A, dolastatins 10 and 15 and halichondrin B and their congeners. Effects on tubulin polymerization, ligand binding interactions and structure-activity relationships are emphasized.
|
| 1300986 |
Immunosuppressive activity of tyrosine analogues of cyclolinopeptide A |
None |
Arch Immunol Ther Exp (Warsz) |
Immunosuppressive activity of tyrosine analogues of cyclolinopeptide A
Abstract
- Immunosuppressive properties of six tyrosine analogues of cyclolinopeptide A were studied and compared with the activity of cyclosporin A. The peptides were investigated using PFC (in vitro) and DTH tests.
|
| 1301382 |
The cloning of the human follicle stimulating hormone receptor and its expression in COS-7, CHO, and Y-1 cells. |
10.1016/0303-7207(92)90220-z |
Mol. Cell. Endocrinol. |
The cloning of the human follicle stimulating hormone receptor and its expression in COS-7, CHO, and Y-1 cells.
Abstract
- Follicle stimulating hormone (FSH) receptor clones were isolated from a human testis cDNA library. Characterization of the cDNA clones showed that the DNA and predicted amino acid sequences of the long open reading frame differed from a previously published human ovarian FSH receptor sequence (Minegish et al. (1991) Biochem. Biophys. Res. Commun. 175, 1125-1130) by seven nucleotides and five amino acids. A human FSH receptor splice variant was also identified and characterized. A full-length human FSH receptor cDNA was engineered for expression in COS-7, CHO, and Y-1 cells. In transient transfections of COS-7 cells and stable transfections of Y-1 cells, efficient FSH receptor mRNA accumulation and isolation of FSH-responsive cell lines occurred only when an intron was included in the 5' untranslated region of the FSH receptor transcription unit. Y-1 cells stably transfected with the FSH receptor responded to FSH treatment by rounding up and by synthesizing increased amounts of progesterone. Stably transfected CHO cell lines, which responded to FSH by synthesizing increased amounts of cAMP, were isolated irrespective of the presence of the heterologous intron. The FSH-responsive CHO and Y-1 cell lines may be suitable for the development of better in vitro FSH bioassays. These cells also constitute a convenient source of human FSH receptor protein for use in radioreceptor assays and in studies of receptor-ligand interactions.
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