Morphological evidence for a permeability barrier in the testis and spermatic duct ofGymnotus carapo(Teleostei: Gymnotidae)

2015 ◽  
Vol 82 (9) ◽  
pp. 663-678 ◽  
Author(s):  
Lara C. Meneguelli De Souza ◽  
Claudio A. Retamal ◽  
Gustavo M. Rocha ◽  
Maria Luisa Lopez
Keyword(s):  
Morphological Evidence ◽  
Permeability Barrier ◽  
Spermatic Duct

Morphological evidence of a permeability barrier in urodele testis

1982 ◽  
Vol 80 (3) ◽  
pp. 253-263 ◽  
Author(s):  
Emilia Franchi ◽  
Marina Camatini ◽  
Ivan Decurtis
Keyword(s):  
Morphological Evidence ◽  
Permeability Barrier

Scanning and Transmission Electron Microscopy of Endomentrium in Women Wearing TCu-380-A IUD 's

1977 ◽  
Vol 35 ◽  
pp. 666-667
Author(s):  
A. Gonzalez Angulo ◽  
R. Berlioz ◽  
R. Aznar
Keyword(s):  
Copper Wire ◽  
Uterine Cavity ◽  
Morphological Evidence ◽  
Secretory Phase ◽  
Ultrastructural Studies ◽  
Proliferative Phase ◽  
Contraceptive Devices ◽  
Transmission Electron ◽  
Intrauterine Contraceptive ◽  
Myelin Figure

Recent ultrastructural studies on endometrial tissues from women wearing copper, wire intrauterine devices have disclosed morphological evidence of impaired glycogen degradation and secretion resulting in interference with the viability of blastocysts. Reduced microapocrine secretion observed with the scanning electron microscope supports this (1). In addition, organelle modifications have been observed in the epithelial cells of these women. The changes are seen in biopsies taken in the proliferative phase of the cycle and consist of mitochondrial vacuolation and myelin figure formation. These modifications disappear in the secretory phase and therefore have been regarded as reversible (2).The aim of the present studies was to investigate surface epithelial changes as well as organelle modifications in relation to the site of contact with an IUD that releases greater amounts of copper. Endometrial tissue was obtained from the uterine cavity of four young women wearing TCu-380-A intrauterine contraceptive devices for 4-6 weeks.

Microanatomy of the Periplasm of Bacillus Licheniformis

1971 ◽  
Vol 29 ◽  
pp. 262-263
Author(s):  
B.K. Ghosh
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Bacillus Licheniformis ◽  
External Environment ◽  
Permeability Barrier ◽  
Periplasmic Space ◽  
Modified Technique ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.

Ultrastructural Study of a differentiating human colon carcinoma cell line

1990 ◽  
Vol 48 (3) ◽  
pp. 208-209
Author(s):  
Sylvie Polak-Charcon ◽  
Mehrdad Hekmati ◽  
Yehuda Ben Shaul
Keyword(s):  
Cell Line ◽  
Morphological Changes ◽  
Secretory Granules ◽  
Human Colon ◽  
Cell Types ◽  
Culture Conditions ◽  
Morphological Evidence ◽  
Human Colon Carcinoma Cell ◽  
Colon Cell

The epithelium of normal human colon mucosa “in vivo” exhibits a gradual pattern of differentiation as undifferentiated stem cells from the base of the crypt of “lieberkuhn” rapidly divide, differentiate and migrate toward the free surface. The major differentiated cell type of the intestine observed are: absorptive cells displaying brush border, goblet cells containing mucous granules, Paneth and endocrine cells containing dense secretory granules. These different cell types are also found in the intestine of the 13-14 week old embryo.We present here morphological evidence showing that HT29, an adenocarcinoma of the human colon cell line, can differentiate into various cell types by changing the growth and culture conditions and mimic morphological changes found during development of the intestine in the human embryo.HT29 cells grown in tissue-culture dishes in DMEM and 10% FCS form at late confluence a multilayer of morphologically undifferentiated cell culture covered with irregular microvilli, and devoid of tight junctions (Figs 1-3).

Beneficial effect of curcumin on epidermal permeability barrier function

Planta Medica ◽  
2008 ◽  
Vol 74 (09) ◽  
Author(s):  
HY Jeon ◽  
JK Kim ◽  
JE Lee ◽  
WG Kim ◽  
SJ Lee
Keyword(s):  
Beneficial Effect ◽  
Barrier Function ◽  
Permeability Barrier ◽  
Epidermal Permeability Barrier

Ultrastructural evidence of transplacental transport of immunoglobulin G in bitches

Reproduction ◽  
2000 ◽  
pp. 315-326 ◽  
Author(s):  
MH Stoffel ◽  
AE Friess ◽  
SH Hartmann
Keyword(s):  
Mammary Gland ◽  
Basement Membrane ◽  
Immunoglobulin G ◽  
Passive Immunity ◽  
Morphological Evidence ◽  
Membrane Material ◽  
Ultrastructural Evidence ◽  
Cytotrophoblast Cells ◽  
Fetal Vessels

In dogs, passive immunity is conferred to fetuses and neonates by the transfer of maternal immunoglobulin G through the placenta during the last trimester of pregnancy and via the mammary gland after parturition, respectively. However, morphological evidence of transplacental transport is still lacking. The aim of the present study was to localize maternal immunoglobulin G in the labyrinthine zone and in the haemophagous zone of the canine placenta by means of immunohistochemistry and immunocytochemistry. In the labyrinthine zone, immunoglobulin G was detected in all the layers of the materno-fetal barrier including the fetal capillaries. Immunoreactivity was particularly prominent in maternal basement membrane material as well as in the syncytiotrophoblast. However, this evidence of transplacental transport of immunoglobulin G originated from a limited number of unevenly distributed maternal vessels only. In the cytotrophoblast of the haemophagous zone, immunoglobulin G was localized to phagolysosomes at various stages but was never detected within fetal vessels. The results indicate that maternal immunoglobulin G is degraded in cytotrophoblast cells of the hemophagous zone and, therefore, that transplacental transport is restricted to a subpopulation of maternal vessels in the labyrinthine zone.

Diversification of the North American Doellingeria-Eucephalus Clade (Astereae: Asteraceae) Inferred from Molecular and Morphological Evidence

2019 ◽  
Vol 44 (4) ◽  
pp. 930-942
Author(s):  
Geraldine A. Allen ◽  
Luc Brouillet ◽  
John C. Semple ◽  
Heidi J. Guest ◽  
Robert Underhill
Keyword(s):  
North American ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
Morphological Evidence ◽  
South American ◽  
New Combinations ◽  
The North ◽  
Hybridization Event ◽  
Ancient Hybridization

Abstract—Doellingeria and Eucephalus form the earliest-diverging clade of the North American Astereae lineage. Phylogenetic analyses of both nuclear and plastid sequence data show that the Doellingeria-Eucephalus clade consists of two main subclades that differ from current circumscriptions of the two genera. Doellingeria is the sister group to E. elegans, and the Doellingeria + E. elegans subclade in turn is sister to the subclade containing all remaining species of Eucephalus. In the plastid phylogeny, the two subclades are deeply divergent, a pattern that is consistent with an ancient hybridization event involving ancestral species of the Doellingeria-Eucephalus clade and an ancestral taxon of a related North American or South American group. Divergence of the two Doellingeria-Eucephalus subclades may have occurred in association with northward migration from South American ancestors. We combine these two genera under the older of the two names, Doellingeria, and propose 12 new combinations (10 species and two varieties) for all species of Eucephalus.

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