scholarly journals Three-dimensional structure of the lingual papillae of healthy rats and rats with experimental diabetes mellitus (in the context of mechanism of development of diabetic glossitis)

2017 ◽  
Vol 8 (1) ◽  
pp. 58-65
Author(s):  
S. L. Popel’ ◽  
O. V. Baskevich ◽  
V. M. Zhurakіvskyi ◽  
O. Y. Zhurakіvska ◽  
I. V. Melnik ◽  
...  

We studied the three-dimensional structure and patterns of distribution of the lingual papillae of healthy rats (the norm) and their changes in the process of development of diabetes mellitus І type. The research was conducted on 65 laboratory rats of the Weestar line. The research investigated the mucus shell and the microcirculatory network of the tongue. The distribution and three-dimensional structure of the papillae of the tongue were studied using a scanning electron microscope. It was found that there are 5 morphological subspecies of filiform papillae on the dorsal surface of body of the tongue: true filifom, flattened, thin and giant conical and brush-like. Isolated fungiform papillaе are unevenly distributed between filiform papillaе. The dorso-lateral edge of the dorsal lingual surface is covered by foliate papillae. The unique oval papilla vallate is located in the back-end of the middle line of the root of the tongue. The far back of the root of the tongue lacks papillae, is flattened and covered by squamous formations. The distribution and types of lingual papillae is similar in rats to other rodents. In the process of development of diabetic glossitis a reduction in the height of different types of papillae of the tongue was observed, and an increase in the amount of keratinized mass, which plays a role in the fixation of microflora on the surface of the mucus shell, which as a result may lead to development of inflammatory process in the tongues of rats with experimental diabetes mellitus. The stages of morphological and morphometric changes in the mucus shell and microcirculatory network of the tongues of rats with diabetes mellitus were investigated, the characteristic signs of these changes were marked. On the basis of morpho-functional changes of the tongues of rats with experimental streptozotocin induced diabetes mellitus, two stages of development of pathomorphological changes were distinguished: 1) reactive changes (2–4th week) and 2) destructive processes (6–8th week). At the end of the first stage there was a reduction in height of the filiform papillae and width of mushroom-like papillae in the mucus shell of the tongue, an increase in its keratinization, a considerable reduction in the number of cells in the deeper layers of the epithelium of the tongue and the adsorption capacity of superficial epіtheliocites diminished, a significant reduction in the diameter of path clearance of all departments of the microcirculatory network is traced here. At the end of the secondary stage, there was a reduction in the sizes of all papillae of the back of the tongue, in all links of the microcirculatory network there was a development of diabetic microangiopathy which is characterized: by narrowing of the arterial and exchange links on a background expansion of capacity link. The question of influencing the pathological process in the vessels of the microcirculatory network on the state of the mucus shell of the tongue in animals with experimental streptozotocin induced diabetes mellitus is discussed.

2019 ◽  
Vol 25 (5-6) ◽  
pp. 303-308
Author(s):  
A. A Spasov ◽  
Yulia A. Govorova ◽  
L. V Naumehko ◽  
D. A Babkov ◽  
A. S Taran ◽  
...  

Nonenzymatic glycosylation of lens proteins in diabetes mellitus is one of the pathogenetic mechanisms of cataract formation. According to the results of this study, aminoguanidine, which has anti-glycation activity, inhibits cataractogenesis in experimental diabetes. Laboratory animals with streptozotocin-induced diabetes mellitus treated with aminoguanidine showed less clouding in the lenses, and the content of advanced glycation end products, in particular, carboxymethyllysine, in the lenses was found to be reduced compared to the same parameters in animals from the control diabetic group.


2020 ◽  
Vol 27 (4) ◽  
pp. E2020413
Author(s):  
Ihor Bilinskyi

The objective of the research was to determine the morphological features of the duodenal wall of animals within 14-56 days of developing streptozotocin-induced diabetes mellitus using light optical microscopy. Materials and Methods. The research was carried out on 40 white nonlinear adult male rats. Diabetes mellitus was simulated by a single intraperitoneal injection of streptozotocin (Sigma, USA) at a dose of 60 mg/kg body weight. The material was taken from the duodenum on the 14th, 28th and the 56th days after the onset of experimental diabetes mellitus. For histological study, the preparations were made using the conventional method, which included the staining of sections with hematoxylin and eosin. Results. Streptozotocin-induced diabetes mellitus was experimentally found to lead to dystrophic changes in the epithelial components of the duodenal mucosa from the 14th day of developing. There were observed a shortening of the villi of the mucous membrane and a lack of distinctness of striated border contours on the apical surface of epitheliocytes. Between the connective-tissue fibers of the lamina propria of the mucosa and thin-walled vessels, the cellular elements, including mainly macrophages, lymphocytes, were found. There was a shortening of the villi, edema and histiolymphocytic infiltration of the villous stroma 28 days after developing experimental diabetes mellitus. The epithelium covering was discontinuous; numerous areas of desquamation were found at the apex of the villi. Fifty-six days after developing experimental diabetes mellitus, the destruction and desquamation of the epithelium of the villi and crypts were observed. The surface of the duodenal mucosa smoothed down due to the shortening and flattening of the villi (indicating their atrophy), while the crypts elongated and their depth increased. Conclusions. Histological study of the duodenal wall of diabetic animals showed pronounced desquamation at the apex of the villi, destructive and dystrophic changes in the surface epithelium, edema and increased cellular infiltration of the lamina propria of the mucosa. Thus, in diabetes mellitus, structural changes in the duodenal wall of rats are characterized by the dystrophic processes, which can be considered as the morphological reflection of enteropathy.


1988 ◽  
Vol 30 (6) ◽  
pp. 719-731 ◽  
Author(s):  
Kan Kobayashi ◽  
Ken Miyata ◽  
Shin-ichi Iwasaki ◽  
Keiichi Takahashi

2019 ◽  
Vol 2019 ◽  
pp. 1-6
Author(s):  
Eren Altun ◽  
Hasmet Yazici ◽  
Erhan Arslan ◽  
Kamil Gokce Tulaci ◽  
Haydar Ali Erken

Objective. To evaluate the effect of streptozotocin-induced experimental diabetes mellitus on p16, p53, Ki67, and Bcl2 expressions and histopathological changes in the tongue of the rats. Material and Methods. Twenty-two adult female Sprague-Dawley rats were used. The rats were randomly divided into 2 groups (n=14) as control (C) (n=8) and diabetic (DM) (n=6). The rats in the DM group were given streptozotocin as a single intraperitoneal dose for induction of diabetes. Histopathological and immunohistochemical evaluations of formalin-fixed and paraffin-embedded tissue sections of the tongue were used. Results. Significant differences were observed between the DM group and the control group in terms of epithelial thickness, length of filiform papillae, and width of filiform papillae (p=0.005, p=0.001, and p=0.006, respectively). There was no significant difference between the groups in terms of mononuclear inflammatory cell infiltration, capillary proliferation, and dysplasia (p=0.204, p=0.244, and p=0.204, respectively). As a result of immunohistochemical studies, no significant difference was found between the groups in terms of p53, Ki67, and Bcl-2 expressions (p=0.588, p=0.662, and p=0.686, respectively). A significant difference was found between the groups when p16 expression was evaluated (p=0.006). Conclusions. In our study, streptozotocin-induced experimental diabetes mellitus induced p16 expression but did not show any difference in p53, Bcl-2, and Ki67 levels. It should be considered in the studies that the pathological changes at the early stages of the relationship between DM and oral cancer may be related to p16 expression; however, it may also be linked with p16-related aging process.


Author(s):  
N. H. Olson ◽  
T. S. Baker ◽  
Wu Bo Mu ◽  
J. E. Johnson ◽  
D. A. Hendry

Nudaurelia capensis β virus (NβV) is an RNA virus of the South African Pine Emperor moth, Nudaurelia cytherea capensis (Lepidoptera: Saturniidae). The NβV capsid is a T = 4 icosahedron that contains 60T = 240 subunits of the coat protein (Mr = 61,000). A three-dimensional reconstruction of the NβV capsid was previously computed from visions embedded in negative stain suspended over holes in a carbon film. We have re-examined the three-dimensional structure of NβV, using cryo-microscopy to examine the native, unstained structure of the virion and to provide a initial phasing model for high-resolution x-ray crystallographic studiesNβV was purified and prepared for cryo-microscopy as described. Micrographs were recorded ∼1 - 2 μm underfocus at a magnification of 49,000X with a total electron dose of about 1800 e-/nm2.


Author(s):  
David A. Agard ◽  
Yasushi Hiraoka ◽  
John W. Sedat

In an effort to understand the complex relationship between structure and biological function within the nucleus, we have embarked on a program to examine the three-dimensional structure and organization of Drosophila melanogaster embryonic chromosomes. Our overall goal is to determine how DNA and proteins are organized into complex and highly dynamic structures (chromosomes) and how these chromosomes are arranged in three dimensional space within the cell nucleus. Futher, we hope to be able to correlate structual data with such fundamental biological properties as stage in the mitotic cell cycle, developmental state and transcription at specific gene loci.Towards this end, we have been developing methodologies for the three-dimensional analysis of non-crystalline biological specimens using optical and electron microscopy. We feel that the combination of these two complementary techniques allows an unprecedented look at the structural organization of cellular components ranging in size from 100A to 100 microns.


Author(s):  
José L. Carrascosa ◽  
José M. Valpuesta ◽  
Hisao Fujisawa

The head to tail connector of bacteriophages plays a fundamental role in the assembly of viral heads and DNA packaging. In spite of the absence of sequence homology, the structure of connectors from different viruses (T4, Ø29, T3, P22, etc) share common morphological features, that are most clearly revealed in their three-dimensional structure. We have studied the three-dimensional reconstruction of the connector protein from phage T3 (gp 8) from tilted view of two dimensional crystals obtained from this protein after cloning and purification.DNA sequences including gene 8 from phage T3 were cloned, into Bam Hl-Eco Rl sites down stream of lambda promotor PL, in the expression vector pNT45 under the control of cI857. E R204 (pNT89) cells were incubated at 42°C for 2h, harvested and resuspended in 20 mM Tris HC1 (pH 7.4), 7mM 2 mercaptoethanol, ImM EDTA. The cells were lysed by freezing and thawing in the presence of lysozyme (lmg/ml) and ligthly sonicated. The low speed supernatant was precipitated by ammonium sulfate (60% saturated) and dissolved in the original buffer to be subjected to gel nitration through Sepharose 6B, followed by phosphocellulose colum (Pll) and DEAE cellulose colum (DE52). Purified gp8 appeared at 0.3M NaCl and formed crystals when its concentration increased above 1.5 mg/ml.


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