Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 3 (1983), S. 463-483 
    ISSN: 0886-1544
    Keywords: intracellular matrix ; extracellular matrix ; covalently cross-linked matrix ; ε-(γ-glutamic) lysine bonds ; skeletal muscle ; titin ; covalently cross-linked collagen ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: When skeletal, cardiac, and smooth muscle is exhaustively extracted with a protein-unfolding reagent such as 6 M guanidine HCl and a disulfide-reducing reagent such as 5% β-mercaptoethanol, a tissue ghost remains intact and retains the characteristic shape and dimensions of the tissue before extraction. In the case of chicken pectoral muscle, the tissue ghost contains 1% of the original muscle proteins. Guanidine HCl extraction followed by collagenase treatment of glycerol-extracted chicken pectoral muscle releases a clean preparation of elongated structures containing 0.2% of the original protein and representing the covalently cross-linked remnants of the muscle fibers. The material of these muscle fiber ghosts extends throughout the interior of the cell. Antibodies raised against the tissue ghosts of smooth muscle cross-react with glycerol extracted skeletal myofibrils, forming a banding pattern which coincides with the banding pattern observed when myofibrils are reacted with antibodies against titin. Titin, a large and soluble protein found in skeletal muscle, cross-reacts with our antigizzard antibody. However, amino acid analysis of the muscle fiber ghosts indicates that titin cannot be the only subunit of the insoluble polymer, but that one or more proteins with a very high glycine and alanine content and a very low basic and acidic amino acid content must also form part of the covalently cross-linked matrix. The possibility is presented that this matrix may be the basis of the superthin 2-3-nm filaments which have been observed in a variety of cell types.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 205 (1983), S. 159-168 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The effects of the prostaglandin synthesis inhibitor, indomethacin, on the preovulatory morphology of apical follicle walls have been examind by transmission electron microscopy. Immature mice, superovulated with 5 IU pregnant mare serum (PMS) followed 40 hours later by 80 IU luteinizing hormone (LH) were treated with either 10 mg/kg indomethacin or an equivalent volume of the indomethacin vehicle 10 minutes prior to LH. Follicular apices from both groups were compared at 12 hours post-LH. Indomethacin treatment suppressed many of the morphological changes normally occurring in the apex during preovulatory development. Whereas apices from vehicle treated animals demonstrated marked deterioration, dissociation, and thinning of tissue, the cell layers of apices from indomethacin-treated animals remained thickened and tightly packed, with limited signs of disruption. The results presented herein are consistent with the idea that prostaglandins are essential mediators of ovulation and suggest that these lipids augment apical rupture by mobilizing granulosa cells and stimulating the loss of connective tissue elements.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 209 (1984), S. 53-57 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The uptake and retention of a radiolabeled synthetic progestin, ORG 2058, was studied in the female reproductive system of the baboon. Four estrogen-primed baboons were injected intravenously with 2.5 μ/kg body weight of 3H-ORG 2058. One animal, which served as a control, received an additional injection of 2.5 mg/kg body weight of unlabeled progesterone. One hour after the injections, the animals were killed and the uterus, cervix, oviduct, vagina, and labia were removed and processed for autoradiography. The cells in the germinative layers of the stratified squamous epithelium of the cervix, vagina, and labia demonstrated nuclear localization of the label. The columnar epithelium, both surface and glandular, of the uterus and cervix sequestered the synthetic steroid; however, the nuclei of the epithelium lining the oviduct were unlabeled. The nuclei of the fibroblasts and of the smooth muscle cells were labeled in all the organs studied. These preliminary observations suggest that there is a stage in the reproductive cycle in which progesterone receptors are contained in the stromal cells of the oviduct but are absent in the epithelium.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 207 (1983), S. 325-334 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Nucleoprotein changes during male and female pronuclear development have been examined in fertilized hamster eggs utilizing the ammoniacal silver reaction (ASR) at the light and ultrastructural levels of observation. Prior to its incorporation, the paternally derived chromatin was heavily laden with ASR product. Immediately upon gamete fusion the sperm nucleus underwent a dramatic increase in staining, suggesting an augmentation in the availability of reactive sites already present in the sperm nucleus or an accumulation of “new” reactive sites from the egg cytoplasm. With subsequent transformations of the sperm nucleus into a male pronucleus, there was a progressive reduction in ASR product associated with the paternal chromatin. Concomitantly, the condensed maternal chromosomes remaining in the zygote after the conclusion of meiosis dispersed and developed into a female pronucleus; these changes were accompanied by a progressive decrease in ASR staining. At the conclusion of pronuclear development, the morphologically similar male and female pronuclei were diffusely stained with the ASR. The increase in ASR staining of the sperm nucleus immediately following gamete fusion demonstrates a major effect of the egg cytoplasm on the paternal chromatin that, heretofore, has not been recognized. This augmentation and the following decrease in ASR staining may reflect changes in nucleoproteins during pronuclear development. Differences in nuclear staining are discussed in light of previous studies of nucleoprotein transitions at fertilization.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 172 (1982), S. 151-157 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The uptake and retention of radiolabeled estradiol by both the male and female reproductive organs were examined in the baboon. Two male and two female baboons were injected intracardially with 1 μg/kg body weight of 3H-estradiol and two animals, one male and one female, were injected with both labeled and 100 μg/kg body weight of unlabeled estradiol. One and a half hours after the injections, the animals were sacrificed and the uterus, cervix, vagina, oviduct, seminal vesicles, and prostate gland were removed and processed for autoradiography. The stratified squamous epithelia of the cervix and vagina demonstrated a light uptake of the label in the germinative, but not in the superficial cell layers. The columnar cells lining the oviduct and uterine glands were labeled, whereas the luminal epithelium of the uterus and the glandular epithelia of the seminal vesicles and prostate gland did not sequester the tritiated steroid. The interstitial cells of all the organs studied demonstrated a moderate to heavy uptake of the radioactivity, whereas the smooth muscle cells were lightly labeled except in the vagina, in which these cells displayed a moderate number of silver grains.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 25 (1990), S. 110-122 
    ISSN: 1040-452X
    Keywords: DNA-protein interactions ; Embryonic gene regulation ; Regulatory factors ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Expression of the Cylla cytoskeletal actin gene is a marker of differential gene activation in the aboral ectoderm of the early sea urchin embryo. Gene transfer expreiments have defined a 2,300 nucleotide cis-regulatory domain required for the correct spatial and temporal control of this gene. This domain includes at least 20 sites at which relatively stable DNA-protein complexes form in vitro on reaction with embryo nuclear extracts. We report the nucleotide sequence of the whole regulatory domain and map the sites at which high-specificity DNA-protein interactions occur. These were located initially by gel shift assays carried out on progressive restriction digests of given subfragments of the large regulatory domain and were located more exactly by oligonucleotide gel shift competitions. Eight of the sites of specific interaction are unique within the Cyllla regulatory domain, and the remainder consist of five different sites that occur more than once. We observe some well known sequences also found in regulatory regions of other genes, e.g., “CCAAT” and “octamer” elements. The various sites have been classified regarding putative biological function in other work, and the present studies permit an assessment of the number and complexity of interactions constituting each functional class and of the relative locations of sites of each class.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 38 (1994), S. 357-363 
    ISSN: 1040-452X
    Keywords: Placentation ; Cathepsin G ; Elastase ; Antileukoproteinase ; Uterus ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Uterine expression of the mRNA encoding antileukoproteinase (ALP) is highest in pig uterus during mid- to late pregnancy, suggesting a stage of pregnancy-dependent role for this elastase/cathepsin G protease inhibitor in feto-maternal interactions. To examine a potential relationship between uterine synthesis of ALP and the type of placentation in mammalian species, the expression of ALP mRNA and/or protein in pregnant mares, cows, rats, and mice was evaluated. Genomic DNA and mRNA hybridization analyses were performed using a porcine ALP cDNA as probe. The concentration of ALP protein in reproductive tissues was determined by RIA using a polyclonal antibody raised against a synthetic peoptide (ALP 16P) corresponding to amino acid residues 21-36 of the porcine ALP protein. A single ALP mRNA transcript of approximately 0.8 kb in length was detected in equine and bovine uterine tissues. The relative abundance of ALP mRNA in equine endometrium increased between days 125-170 (mid-pregnancy), and then decreased by day 215 of pregnancy. Similarly, the steady state levels of ALP mRNA in bovine endometrium and myometrium were higher during mid- to late than during early pregnancy. The levels of ALP mRNA in bovine fetal cotyledon were low and did not change significantly with stage of pregnancy. No hybridization was detected to pregnant rat endometrial tissues, although high stringency Southern blot analysis of porcine, bovine, and rat genomic DNAs using porcine ALP cDNA as probe predicted a high degree of nucleotide sequence homology in their respective ALP genes. In pregnant cows, concentrations of ALP protein were higher in maternal endometrium and myometrium than in fetal cotyledon. Tissue ALP content in bovine uterus increased between days 17-89, and then decreased by day 248 of pregnancy. In contrast, no ALP protein was detected in cytosolic extracts prepared from endometrium of pregnant rats and mice. THe demonstrated synthesis of ALP mRNA and/or protein in the endometrium of the mare and the cow similar to that of the pig, but not in the endometrium of the rat and mouse, during pregnancy indicates a potential correlation between endometrial ALP expression and epitheliochorial type of placentation in mammalian species. © 1994 Wiley-Liss, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Microscopy Research and Technique 20 (1992), S. 298-304 
    ISSN: 1059-910X
    Keywords: Fertilization ; Sperm-egg interaction ; Gamete fusion ; Egg activation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: A method for correlative studies of early fertilization events that integrates techniques of intracellular electrophysiological recording, video-imaging, and electron microscopy is described. A key feature of the method is its ability to identify the fertilizing sperm and to record the moment of egg excitation. Since the site of gamete interaction is recognizable throughout all stages of preparation, difficulties associated with locating the site of fertilization and determining specimen orientation for microtomy and electron microscopic examination are eliminated. Virtually all samples yield useful information. An example of interacting gametes fixed 4 sec after initiation of the fertilization potential and serial sectioned is described. The method is applicable to systems other than fertilizing eggs when functional, temporal, and spatial relationships of individual cells need to be correlated with changes in ultrastructure.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 28 (1991), S. 380-393 
    ISSN: 1040-452X
    Keywords: Cytoskeleton ; Subacrosomal layer ; Postacrosomal segment ; Spermiogenesis ; Multiple band polypeptides ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The perinuclear theca is a novel cytoskeletal consisting of a densely layered lamina that surrounds the nucleus of mammalian sperm. Using antibodies specific for the multiple band polypeptides present in the perinuclear theca of bull sperm, we show that a heterogeneous group of immunological related proteins are present in the sperm heads of other mammals with greatly different morphologies, including guinea pig, hamster, rat, and mouse. In none of the species were identical groups of immunoreactive polypeptides found, although immunoreactive proteins of molecular weights 65,000 to 80,000 were present in the sperm heads of all species examined. Immunoreactive proteins less than Mr 55,000 were prominent in rat sperm heads and mouse sperm; guinea pig, hamster, and rat sperm heads and mouse sperm had one band in common at approximately Mr 50,000. Different immunoreactive proteins were present in isolated sperm tails. The perinuclear theca first appeared in the subacrosomal space of round to elongating spermatids. Later, with the caudal movement of the manchette, the postacrosomal segment of the perinuclear theca was deposited in a cephalad to caudal direction along the sperm nucleus. Concomitantly, the cytoplasmic space between the nuclear envelope and the plasma membrane narrowed such that only the theca occupied this portion of the sperm head. Immunoreactivity accompanied the ultrastructural appearance of the subacrosomal layer and the postacrosomal segment. The periods of spermiogenesis, in which sub- and post-acrosomal components of the perinuclear theca are formed and the morphogenesis of sperm organelles with which these elements are associated, suggest that components of this cytoskeletal structure function to join the acrosome and the postacrosomal plasma membrane to the nucleus.
    Additional Material: 27 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    American Journal of Anatomy 164 (1982), S. 265-274 
    ISSN: 0002-9106
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In order to demonstrate the possible role of prostaglandins in preovulatory follicular development, immature mice superovulated with pregnant mare serum followed 40 hours later by luteinizing hormone (LH) were treated with the prostaglandin-synthetase inhibitor, indomethacin. Indomethacin (10 mg/kg) injected at varying intervals prior to or following LH inhibited ovulation most effectively when administered within 2 hours of the ovulatory gonadotropin. This inhibition was accompanied by (1) suppression of the morphological changes normally occurring within the follicular wall during preovulatory development and (2) failure of germinal vesicle breakdown (GVBD) in two-thirds of the follicles examined. When GVBD occurred, indomethacin treatment appeared to delay meiotic maturation. Cumulus tissue was more compact than in control follicles and maintained a close association with the oocyte. These results suggest that alterations in the morphology of the follicle prior to ovulation - specifically, thinning of the apical follicular wall and meiotic maturation - are regulated by prostaglandins.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...