The Role of the Visceral Mesoderm in the Development of the Gastrointestinal Tract

2009 ◽  
Vol 136 (7) ◽  
pp. 2074-2091 ◽  
Author(s):  
Valérie A. McLin ◽  
Susan J. Henning ◽  
Milan Jamrich
2020 ◽  
pp. 49-57
Author(s):  
S. V. Orlova ◽  
E. A. Nikitina ◽  
L. I. Karushina ◽  
Yu. A. Pigaryova ◽  
O. E. Pronina

Vitamin A (retinol) is one of the key elements for regulating the immune response and controls the division and differentiation of epithelial cells of the mucous membranes of the bronchopulmonary system, gastrointestinal tract, urinary tract, eyes, etc. Its significance in the context of the COVID‑19 pandemic is difficult to overestimate. However, a number of studies conducted in the past have associated the additional intake of vitamin A with an increased risk of developing cancer, as a result of which vitamin A was practically excluded from therapeutic practice in developed countries. Our review highlights the role of vitamin A in maintaining human health and the latest data on its effect on the development mechanisms of somatic pathology.


1986 ◽  
Vol 34 (4) ◽  
pp. 463 ◽  
Author(s):  
PB Frappell ◽  
RW Rose

The gastric distribution of barium sulphate and its subsequent intestinal passage were examined by radiography in Potorous tridactylus. Barium sulphate administered in association with solid food passed to the sacciform forestomach from the tubiform forestomach. However, ingested barium sulphate suspension mainly entered the hindstomach via the gastric sulcus. Barium sulphate which entered the sacciform forestomach remained for no more than 1 h before passing to the hindstomach via the tubiform forestomach. The passage of contrast medium through the intestine was followed in adults administered barium sulphate suspension only. Contrast medium which entered the hindstomach was not detectable there after 10 min. Barium sulphate first arrived at the caecum and proximal colon after 20 min, and by 45 min the majority had reached these organs. It persisted in the caecum and proximal colon for several hours, during which there was some movement into the descending colon and rectum. These results lead towards a new interpretation of the role of the potoroine foregut and hindgut.


Development ◽  
1998 ◽  
Vol 125 (4) ◽  
pp. 655-666 ◽  
Author(s):  
H.T. Broihier ◽  
L.A. Moore ◽  
M. Van Doren ◽  
S. Newman ◽  
R. Lehmann

In Drosophila as well as many vertebrate systems, germ cells form extraembryonically and migrate into the embryo before navigating toward gonadal mesodermal cells. How the gonadal mesoderm attracts migratory germ cells is not understood in any system. We have taken a genetic approach to identify genes required for germ cell migration in Drosophila. Here we describe the role of zfh-1 in germ cell migration to the gonadal mesoderm. In zfh-1 mutant embryos, the initial association of germ cells and gonadal mesoderm is blocked. Loss of zfh-1 activity disrupts the development of two distinct mesodermal populations: the caudal visceral mesoderm and the gonadal mesoderm. We demonstrate that the caudal visceral mesoderm facilitates the migration of germ cells from the endoderm to the mesoderm. Zfh-1 is also expressed in the gonadal mesoderm throughout the development of this tissue. Ectopic expression of Zfh-1 is sufficient to induce additional gonadal mesodermal cells and to alter the temporal course of gene expression within these cells. Finally, through analysis of a tinman zfh-1 double mutant, we show that zfh-1 acts in conjunction with tinman, another homeodomain protein, in the specification of lateral mesodermal derivatives, including the gonadal mesoderm.


2010 ◽  
Vol 2 ◽  
pp. 88-93
Author(s):  
Elżbieta Maciorkowska ◽  
Ewa Ryszczuk ◽  
Maciej Kaczmarski

2012 ◽  
Vol 78 (19) ◽  
pp. 6799-6803 ◽  
Author(s):  
Sam Abraham ◽  
David M. Gordon ◽  
James Chin ◽  
Huub J. M. Brouwers ◽  
Peter Njuguna ◽  
...  

ABSTRACTThe role ofEscherichia colias a pathogen has been the focus of considerable study, while much less is known about it as a commensal and how it adapts to and colonizes different environmental niches within the mammalian gut. In this study, we characterizeEscherichia coliorganisms (n= 146) isolated from different regions of the intestinal tracts of eight pigs (dueodenum, ileum, colon, and feces). The isolates were typed using the method of random amplified polymorphic DNA (RAPD) and screened for the presence of bacteriocin genes and plasmid replicon types. Molecular analysis of variance using the RAPD data showed thatE. coliisolates are nonrandomly distributed among different gut regions, and that gut region accounted for 25% (P< 0.001) of the observed variation among strains. Bacteriocin screening revealed that a bacteriocin gene was detected in 45% of the isolates, with 43% carrying colicin genes and 3% carrying microcin genes. Of the bacteriocins observed (H47, E3, E1, E2, E7, Ia/Ib, and B/M), the frequency with which they were detected varied with respect to gut region for the colicins E2, E7, Ia/Ib, and B/M. The plasmid replicon typing gave rise to 25 profiles from the 13 Inc types detected. Inc F types were detected most frequently, followed by Inc HI1 and N types. Of the Inc types detected, 7 were nonrandomly distributed among isolates from the different regions of the gut. The results of this study indicate that not only may the different regions of the gastrointestinal tract harbor different strains ofE. colibut also that strains from different regions have different characteristics.


2021 ◽  
Author(s):  
Qi Tian ◽  
Zengzi Zhou ◽  
Luying Wang ◽  
Xin Sun ◽  
Bernard Arulanandam ◽  
...  

Chlamydia is known to both ascend to the upper genital tract and spread to the gastrointestinal tract following intravaginal inoculation. The gastrointestinal Chlamydia was recently reported to promote chlamydial pathogenicity in the genital tract since mice intravaginally inoculated with an attenuated Chlamydia , which alone failed to develop pathology in the genital tract, were restored to develop hydrosalpinx by intragastric co-inoculation with wild type Chlamydia . Gastrointestinal Chlamydia promoted hydrosalpinx via an indirect mechanism since Chlamydia in the gut did not directly spread to the genital tract lumen. In the current study, we further investigated the role of CD8 + T cells in the promotion of hydrosalpinx by gastrointestinal Chlamydia . First, we confirmed that intragastric co-inoculation with wild type Chlamydia promoted hydrosalpinx in mice that were inoculated with an attenuated Chlamydia in the genital tract one week earlier. Second, the promotion of hydrosalpinx by intragastrically co-inoculated Chlamydia was blocked by depleting CD8 + T cells. Third, adoptive transfer of the gastrointestinal Chlamydia -induced CD8 + T cells was sufficient for promoting hydrosalpinx in mice that were intravaginally inoculated with an attenuated Chlamydia . These observations have demonstrated that CD8 + T cells induced by gastrointestinal Chlamydia are both necessary and sufficient for promoting hydrosalpinx in the genital tract. The study has laid a foundation for further revealing the mechanisms by which Chlamydia -induced T lymphocyte responses (as a 2 nd hit) promote hydrosalpinx in mice with genital Chlamydia -triggered tubal injury (as a 1 st hit), a continuing effort in testing the two-hit hypothesis as a chlamydial pathogenic mechanism.


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