Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.17 (lysozyme)
 21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Estrogen is an essential requirement for the postpubertal trophic development and maintenance of the differentiated state of the oviduct, uterus, cervix, vagina and mammary glands of mammals. Estrogen, apparently functioning through its specific cytoplasmic receptor protein via a multistep interaction pathway induces gene expression of specific biochemical events leading to growth and differentiation of target tissues (Jensen et al., Proc Natl Acad Sci, 59:632, 1968; Gorski et al., Recent Prog Horm Res 24:45, 1968). One biochemical expression of the estrogen gene is the synthesis of specific mRNA transcripts for certain specific marker proteins, including ovalbumin, lysozyme and ovomucoid in the chick oviduct (O'Malley and McGuire, Proc Natl Acad Sci 60:1527, 1968; Palmiter and Schimke, J Biol Chem 248:1502, 1973), tubulin in the mammalian oviduct (Brenner and Anderson, Handbook of Physiology 7(2):123, 1973; Brenner et al., Endocrinology 95:1094, 1974) and peroxidase (EC 1,11.1.7) in the rodent uterus (Brockelmann and Fawcett, Biol Reprod 1:59, 1969; Churg and Anderson, J Cell Biol 62:449, 1974; Anderson et al., J Cell Biol 64:668, 1975).
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PMID:Reproductive tract peroxidases as endproducts of estrogen-specific gene expression. 51 22

The advantages of breast feeding are due to numerous factors i.e. the favourable composition of basic nutritives, the content of nucleotides, polyamines, rare fatty acids and rare oligo- and polysaccharides in human milk, its high content of immunologically active substances like immunoglobulins, fats, glycoproteins, lysozyme and lactoferrin, and the psychologically important opportunity for close sensual contact between mother and infant. Involution of the uterus is greatly accelerated by breast feeding. In case the mother has to take certain drugs her breast feeding can be disadvantageous for the infant. At present, we do not see any reason to recommend discontinuation of breast feeding because of the relatively high DDT content found in human milk, since the concentration observed has shown no toxic effects. Furthermore a decrease of DDT concentration in human milk has been observed recently.
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PMID:[Advantages of breast feeding (author's transl)]. 124 38

The glucocorticoid receptor of rat liver recognizes nucleotide sequences near the promoter of mouse mammary tumour virus (MMTV) required for hormonal induction in gene transfer experiments. Similar nucleotide sequences have been found in the human metallothionein gene IIA and in the chicken lysozyme gene, the later induced also by oestrogen, progesterone and androgens. In microinjection experiments, deletion of only 44 base pairs (bp) of the lysozyme promoter (from -208 to -164) results in coordinated loss of progesterone and glucocorticoid-dependent gene expression. We show here that purified glucocorticoid receptor from rat liver and progesterone receptor from rabbit uterus yield similar or overlapping exonuclease III footprints in the promoter regions of MMTV and chicken lysozyme. Thus, the regulatory elements for different steroid hormones may be similar or at least share structural features.
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PMID:Glucocorticoid and progesterone receptors bind to the same sites in two hormonally regulated promoters. 298 19

A primary, malignant pleomorphic giant cell tumor of the uterus was studied by light and electron microscopy. The tumor was characterized by spindle cells, plump epithelioid cells, pleomorphic giant cells, osteoclast-like giant cells, and foamy xanthomatous cells. Histochemically, tumor cells did not show either myogenic or epithelial characteristics. Immunohistochemically, tumor cells were devoid of evidence of desmin, cytokeratin, myoglobin, and lysozyme (muramidase), but vimentin was weakly positive, and alpha 1-antichymotrypsin was weakly positive in the cytoplasm of pleomorphic giant cells. Ultrastructurally, tumor cells did not show either myogenic or epithelial features, but they resembled a variant of malignant fibrous histiocytoma. The present case was classified as a storiform-pleomorphic and giant cell type of malignant fibrous histiocytoma of the soft tissues. The uterus is considered to be an additional possible site of malignant fibrous histiocytoma.
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PMID:Malignant fibrous histiocytoma of the uterus. 303 Sep 5

The likely functions of uterine secretions, often termed histotroph, in the nurture of the early conceptus are reviewed. Particular emphasis has been placed on the pig in which the uterus synthesizes and secretes large amounts of protein in response to progesterone. In this species, which possesses a non-invasive, diffuse type of epitheliochorial placentation, the secretions provide a sustained embryotrophic environment which is distinct from that of serum. A group of basic proteins dominates these uterine secretions after Day 11 of pregnancy and its best characterized member is uteroferrin, an iron-containing acid phosphatase with a deep purple colour. Evidence has accumulated to suggest that uteroferrin, rather than functioning as an acid phosphatase, is involved in transporting iron to the conceptus. Three basic polypeptides which are found noncovalently associated with uteroferrin have been shown to be antigenically closely related to one another and to have arisen by post-translational processing from a common precursor molecule. Their function is unknown. A group of basic protease inhibitors has been identified which bear considerable sequence homology to bovine pancreatic trypsin inhibitor (aprotinin) and may control intrauterine proteolytic events initiated by the conceptuses. The last basic protein so far characterized is lysozyme which is presumed to have an antibacterial role. Finally, two low molecular weight (Mr approximately 18,000) acidic polypeptides have been purified and have sequence homology to a plasma retinol binding protein. Like uteroferrin, these proteins may be responsible for transport of an essential nutrient to the conceptus.
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PMID:The functions of uterine secretions. 328 51

The chicken lysozyme gene can be induced in oviduct cells by four classes of steroid hormones, including glucocorticosteroids and progestins. The glucocorticosteroid receptor of rat liver and the progesterone receptor of rabbit uterus both bind, although with different relative affinities, to two sites in the promoter region of the chicken lysozyme gene located, respectively, between 50 and 80 and between 160 and 200 base pairs upstream of the transcription start point. Now we show that the purified progesterone binding unit of the chicken oviduct progesterone receptor (Mr 110,000, or so-called B subunit) generates a DNase I protection pattern ("footprint") in the promoter-distal site that is longer than the footprint generated by the glucocorticosteroid receptor. Methylation protection studies within the promoter-distal binding site identify four contact points for the chicken progesterone receptor and three contact points for the glucocorticosteroid receptor, of which only one is shared by both receptors. Computer graphics models allow one to envisage a different interaction of each receptor with the B form of the DNA double helix.
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PMID:Receptors for glucocorticosteroid and progesterone recognize distinct features of a DNA regulatory element. 345 41

The secretory proteins of the mucosa of the cervix, uterus, and fallopian tubes were investigated by measuring the proteins that were released by isolated mucosal areas. Initial screening disclosed that the immunoglobulins IgG and IgA were released in measurable quantities, but that IgM and the secretory (T) piece of IgA were either absent or present only in trace amounts. Relatively low levels of diffusable total complement activity and the C3 component of complement were present, whereas the C1q, C1r, and C4 components were either absent or present only in trace quantities. No neutral proteinase activity was present, but lysozyme, plasminogen activator, alpha 1-antitrypsin, and alpha 1x-antichymotrypsin could be found in reasonable amounts. The site of secretion, concentration, and cyclic variation of the proteins that diffused from the mucosal sites in measurable quantities were studied. The types and amounts of protein secreted by a particular site in the cervix, uterus, or fallopian tube varied from those of protein from other sites, even within the same organ. During the menstrual cycle, variations occurred in the amount of protein secreted by each mucosal site. However, whether an increase or a decrease in the release of a particular protein took place varied with each protein, even at the same site. The mucosal sites also differed from each other in their response to the phase of the menstrual cycle, that is, whether more or less protein was released, even sites within the same organ. The conclusion is that each organ and even different sites within an organ can respond independently from each other to changes in hormone levels, producing different types and amounts of secretory proteins. The amount of diffusable protein produced by an individual site during the menstrual cycle depends on the type of protein as well as the mucosal site.
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PMID:Diffusable proteins of the mucosa of the human cervix, uterus, and fallopian tubes: distribution and variations during the menstrual cycle. 392 Sep 15

A chronic infiltration of polymorphonuclear leukocytes was invariably found in the infertile regions of uteri containing foreign bodies in conventional rats, germfree rats, mice, and rabbits. Polymorphonuclear leukocytes were never found in the fertile regions of these uteri. A foreign body in the uterus of the rat, and probably also the mouse, was associated with a bacterial infection which spread the inflammatory response throughout the horn containing the foreign body, and in the mouse occasionally into the control horn as well. No bacteria could be cultured from the rabbit uterine horn containing a foreign body. In the germfree rat, both the infiltration of polymorphonuclear leukocytes into the uterus and fertility were significantly different from that observed in the conventional rat. Whereas in the conventional rat the inflammation and infertility extended along the entire length of the uterine horn containing a small foreign body, in the germfree rat the inflammation and infertility were closely correlated to the position of the foreign body. As judged by measurements of lysozyme in the uterine lumens of rats and rabbits, polymorphonuclear leukocytes released their contents into solution in the uterine lumen. It is concluded that some substance derived from polymorphonuclear leukocytes may exert toxic effects on fertilized ova or on spermatozoa and thus be responsible for the infertility of uteri containing foreign bodies.
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PMID:The relationship of polymorphonuclear leukocytes to infertility in uteri containing foreign bodies. 603 52

The roles of uterine inflammation and infection in creating an environment hostile to fertilized eggs or spermatozoa which would explain the contraceptive action of IUDs were investigated in the rat, rabbit, and mouse. Inflammation, as evidenced by the appearance of polymorphonuclear leucocytes, was always present along with a foreign body, and inflamed areas corresponded to regions of known infertility: the entire length of the horn containing the foreign body in the rat uterus, the corresponding horn as well as part of the control horn in the mouse, and only the tissue in contact with the foreign body in the rabbit. Acute inflammatory response (polymorphonuclear stage) persisted indefinitely after insertion of the IUD. Lysozyme measurements in rat and rabbit uteri indicated that polymorphonuclear leucocytes released their contents into the lumen in infertile regions. Cultured rat uteri containing foreign bodies were found to contain over 100 million bacteria of mixed species (compared to none in controls), while rabbit uteri appeared bacteria free. The effects of inflammation were separable from those of infection, however, with the use of germ-free rats. The presence of a foreign body in these rats was associated with a very localized inflammation, with lysozyme only in the segment in contact with the foreign body. Fertilized eggs entered and implanted in the noninflamed region when the foreign body was in the cervical end of the horn; when it was in the ovarian end, all ova were killed, indicating that the antifertility effect of the IUD was possible in absence of bacteria. It is concluded that some component of the polymorphonuclear leucocyte may kill fertilized eggs and thus be responsible for the infertility of uteri containing IUDs.
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PMID:A possible role for granulocytes in the action of intrauterine contraceptive devices. 608 36

Endometrial explants were removed from uteri of animals pregnant and pseudopregnant (5 mg oestradiol valerate on Days 11--15) for 60 days, from the gravid and non-gravid horns of unilaterally pregnant pigs at Day 60 of pregnancy and fron non-pregnant animals at Day 12 of the oestrous cycle. The tissues were cultured in the presence of L-[34S]methionine for 24 h, and the tissues and medium were then analysed separately by two-dimensional polyacrylamide gel electrophoresis. Radioactive polypeptides were identified by autoradiography of dried gels. Tissues from all all except the cyclic animals released an identical group of polypeptides into the culture medium: the major radioactive products were 4 acidic polypeptides of low molecular weight and several basic proteins, which included the purple phosphatase uteroferrin, and lysozyme. In separate experiments explants from 3 unilaterally pregnant pigs were cultured with L-[3H]leucine, and, on a fresh weight basis, the tissue from the non-gravid horn released significantly less radioactive macromolecular material into the medium in 24 h than did tissue from gravid horns. It therefore appears that although the nature of the secretion produced by the pregnant uterus is a consequence of maternal hormonal regulation alone, the tissue underlying a conceptus is quantitatively more active than that from unoccupied regions of a uterus.
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PMID:Effect of the conceptus on quantitative and qualitative aspects of uterine secretion in pigs. 743 27


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