Hepatotoxic effects of melamine exposure from the weaning period in rats: a flow cytometric, electron microscopic, and histopathologic study

2021 ◽  
Author(s):  
Zuleyha Erisgin ◽  
Hasan Serdar Mutlu ◽  
Yavuz Tekelioglu ◽  
Engin Deveci ◽  
Ugur Seker

Abstract This study aims to investigate the effects of melamine exposure from the weaning period (21st postnatal days in rats) on liver tissue. Female Wistar albino rats (n = 18) were divided into three groups. About 0.1-ml saline was applied to the control group by gavage for 21 days from the postnatal 21st day. The second group was taken 50-mg/kg melamine (in 0.1-ml saline) and the third group was taken 75-mg/kg melamine (in 0.1-ml saline) p.o. On the postnatal 45th day, all rats were sacrificed under anesthesia. Then, liver tissues were cut into three parts and two of them placed in neutral formalin for histopathological and flow cytometric analysis, and one of them placed in 2.5% glutaraldehyde. Histopathological analysis was performed with hematoxylin & eosin, Masson trichrome, periodic acid Schiff stained sections, and also with transmission electron microscopy. Apoptosis (Annexin V positivity) was analyzed by flow cytometry. According to histopathological analysis, hepatocyte damage, sinusoidal dilatation, and inflammatory cell infiltration significantly increased in both melamine groups compared with the control group. Apoptosis significantly increased in the 50 and 75-mg melamine groups compared with the control group. In the results of transmission electron microscopy analysis, there was abnormal chromatin distribution in the hepatocyte nuclei, loss in the cristae of the mitochondria, and organelle loss in large areas in the cytoplasm in both melamine exposure groups. As result, melamine exposure from the weaning period causes liver damage with increasing doses.

1995 ◽  
Vol 32 (6) ◽  
pp. 719-721 ◽  
Author(s):  
K. N. M. Khan ◽  
J. E. Sagartz ◽  
G. Koenig ◽  
K. Tanaka

Systemic mastocytosis was diagnosed in a 4-year-old, female Nubian goat. Clinically, the animal was depressed and had severe macrocytic hypochromic anemia and leukopenia. Postmortem examination revealed neoplastic mast cells invading the heart, lung, liver, spleen, lymph nodes, and bone marrow. Eosinophils were frequently admixed with infiltrating mast cells in all organs. Using routine light microscopy, histochemistry, and transmission electron microscopy, metachromatic and periodic acid—Schiff–positive granules were identified within the cytoplasm of neoplastic mast cells. Erythrophagocytosis was observed in some neoplastic cells, although its contribution to the anemia was not clear. This report represents the first description of mast cell neoplasia in the goat.


2012 ◽  
Vol 49 (1) ◽  
pp. 82-88 ◽  
Author(s):  
Jorge Fonseca ◽  
José Martins-dos-Santos ◽  
Pedro Oliveira ◽  
Nuno Laranjeira ◽  
Artur Aguas ◽  
...  

CONTEXT: Only a few studies evaluated the digestive alterations caused by low frequency noise (LFN) and most focused only on mucosal alterations. OBJECTIVES: To investigate the morphological injury of LFN-exposed gastric wall, beyond the epithelial layer. METHODS: Wistar rats were exposed to low frequency noise (LFN), during increasing periods, 1 to 13 weeks. A control group was kept in silence. Gastric specimens were studied using: (i) light microscopy with hematoxylin-eosin and immunostaining for collagens; (ii) transmission electron microscopy; (iii) morphometry allowing statistical analysis. RESULTS: Submucosa of all LFN-exposed animals exhibit increased thickness with fibrous proliferation. Transmission electron microscopy showed massive collagen deposition. Immunostaining identified collagen IV as responsible for the increased thickness. Morphometry allowed the demonstration of a significant difference of thickness between control and exposed groups. Vascular alterations included: i) intima proliferation and thickening, rupture of the internal elastic lamina, thrombotic changes; ii) thickening of the media; iii) after 9 weeks of LFN-exposure, we found new formed vessel presenting tortuous and twisted. There is a significant difference of arterial wall thickness between control and exposed groups. CONCLUSIONS: Deeper layers of gastric wall undergo alterations, including fibrosis of the submucosa caused by collagen IV deposition, an early marker of neoangiogenesis. Vascular alterations included thickening and thrombotic phenomena, but also images of newly formed vessels. This study suggests that, at least in the stomach, LFN-induced fibrosis could be linked with neoangiogenesis.


2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Ren-Qian Tan ◽  
Zhi Zhang ◽  
Jing Ju ◽  
Jiang-Hong Ling

Gastrointestinal (GI) motility disorder is caused by excessive autophagy of the interstitial cells of Cajal (ICC). Chaihu Shugan Powder (CSP) is a traditional Chinese medicine with therapeutic benefits in GI motility disorders; however, the underlying mechanism of its therapeutic effect in GI disorders, especially autophagy of ICC, remains unclear. Thus, this study investigated the effects of CSP-contained serum on glutamate-induced autophagy in rat gastric ICC, exploring its underlying mechanism. In vitro cultured rat stomach ICC were identified by fluorescence microscopy and then stimulated with glutamate (5 mmol/L) for 3 h to establish the autophagy model. These cells were then treated with 10% CSP-containing serum or the autophagy inhibitor 3-methyladenine (3-MA; 5 mmol/L) for 24 h. The control group was cultured with only 10% serum containing physiological saline. The viability of ICC was measured by the CCK-8 assay. The ultrastructure and autophagosomes of ICC were observed using transmission electron microscopy. LC3 expression was detected by immunofluorescence, and LC3, Beclin1, Bcl2, and PI3KC3 expression was detected by western blot analysis. Transmission electron microscopy showed abundant endoplasmic reticulum, mitochondria, and other organelles in the control group, whereas the cells in the autophagy model control group had clear autophagic vacuoles, which were not apparent in both CSP and 3-MA groups. ICC viability was significantly increased by CSP and 3-MA interventions (P < 0.01), accompanied by a decrease in LC3 fluorescence (P < 0.01). Moreover, the expression levels of LC3II/I, Beclin1, and PI3KC3 were significantly decreased (all P < 0.01) with CSP and 3-MA treatment, while Bcl2 expression level was higher than that of the model group (P < 0.01). Thus, CSP can reduce autophagic damage by enhancing Bcl2 expression and downregulating the expression of LC3, Beclin1, and PI3KC3 to protect ICC. These results highlight the potential of CSP in the treatment of GI motility disorders.


1987 ◽  
Vol 35 (3) ◽  
pp. 393-399 ◽  
Author(s):  
H K Lo ◽  
T I Malinin ◽  
G I Malinin

Oxidation of araldite-embedded liver sections by 1% w/v aqueous H5IO6 for 15 min and a 5-min reaction of carbonyls with 1% w/v thiocarbohydrazide in 10% v/v acetic acid was employed for subsequent staining of glycogen with silver-proteinate (S-P). The network of branching intracellular glycogen aggregates was revealed by 15-min staining with S-P, whereas 24 hr incubation in S-P was necessary to enhance the contrast of glycogen inclusions. We conclude that the proposed modification of glycogen staining readily affords the means for its localization at a desired level of contrast and resolution.


Author(s):  
S. Yamashiro ◽  
D. Wilson ◽  
J. St. George ◽  
D. Hyde ◽  
C. Plopper ◽  
...  

In the past, ozone inhalation studies have focused on the lower airways and lung parenchyma. The purpose of this study was to evaluate the effects of ozone on submucosal glands of upper airways. Six adult male bonnet monkeys were exposed to 0.64 ppm ozone continuously for 7 days, and three were exposed to chamber conditions without ozone. The animals were exsanguinated under barbiturate anesthesia. The trachea and lung were fixed by airway infusion of Karnovsky's fixative, which was adjusted to pH 7.4 and 440 milliOsmols. Sagittal sections of ventral trachea were embedded in glycol methacrylate and Araldite 502 for light and electron microscopy. One micrometer methacrylate sections were stained with Alcian blue-periodic acid Schiff (AB/PAS). Selected areas of Araldite-embedded tissue were sectioned for transmission electron microscopy, stained with uranyl acetate and lead citrate and examined with a Zeiss EM 10. Volume percentages of the lumen, granular and nongranular regions of fhe gland and the duct wall, respectively, were estimated by stereologic methods on AB/PAS stained sections.


1992 ◽  
Vol 101 (5) ◽  
pp. 395-402 ◽  
Author(s):  
Timothy T. K. Jung ◽  
Young Min Park ◽  
David Panossian ◽  
Douglas Weeks ◽  
Stanley K. Miller ◽  
...  

Our previous studies revealed that injury to the ciliated cells of the eustachian tube may be the primary cause of irradiation-induced serous otitis media. The purpose of this study was to investigate the effects of the radioprotector WR2721 on irradiation-induced injury to ciliated cells of the eustachian tube (ET) in chinchillas. Twelve chinchillas were divided into two groups: the control group and the experimental group, which was pretreated with a single intraperitoneal dose of the radioprotector S-2-[3-aminopropylamino]ethylphosphorothioic acid (WR2721) 400 mg/kg. The two groups were exposed to 30 Gy of 13-MeV electrons in a single fraction to the area of the bullae and nasopharynx. Ciliary dysfunction was tested and ciliated cells of the ET were examined by scanning and transmission electron microscopy. Pretreatment with WR2721 was found to protect ciliated cells of the ET from irradiation injury.


1977 ◽  
Vol 25 (9) ◽  
pp. 1069-1073 ◽  
Author(s):  
L E Thornell ◽  
M Sjöström ◽  
U Karlsson ◽  
E Cedergren

Glycogen in nerve terminals from the reticular zone of frog muscle was identified by transmission electron microscopy of both periodic acid-thiosemicarbazide-silverproteinate treated and UAc-PbCi-stained serial sections. A variable appearance of glycogen in the uranylacetate-lead citrate-stained nerve terminals was seen and is related to the preparative procedure. The study indicates the necessity of cytochemical identification for the assessment of glycogen organization in cells.


2013 ◽  
Vol 61 (3) ◽  
pp. 344-353 ◽  
Author(s):  
Carmen Solcan ◽  
Dorina Timofte ◽  
Viorel Floristean ◽  
Stuart Carter ◽  
Gheorghe Solcan

A study was conducted to evaluate the nephrotoxic effect of ochratoxin A (OTA) in broiler chickens. Forty Ross 308 broilers (6 days old) were divided into two groups: one group received daily, by gavage, ochratoxin A at a daily dose of 50 μg/kg body weight for up to 21 days, while the control group received only diluent (sunflower oil). After 21 days, the chickens were euthanised and the kidneys removed for analysis by histopathology and immunohistochemistry to detect an anti-apoptotic marker (Bcl-2), and by transmission electron microscopy. Macroscopically the kidneys were enlarged, showing degeneration and gout deposits. Histologically, glomerulonephrosis and tubulonephrosis were common lesions in all chicks. In two of the five chicks exposed to OTA for 21 days, focal tubular cell proliferation, multiple adenoma-like structures and Bcl-2-positive epithelial cells were identified in layers of the renal papilla and in convoluted tubules. Transmission electron microscopy of the proximal convoluted tubules identified abnormal forms of mitochondria. The nephrotoxic effect of ochratoxicosis in chickens is probably due to carcinogenic changes induced in the epithelial tissues.


Blood ◽  
1981 ◽  
Vol 58 (1) ◽  
pp. 14-19 ◽  
Author(s):  
GM Brodeur ◽  
DL Williams ◽  
AT Look ◽  
WP Bowman ◽  
DK Kalwinsky

We describe two adolescent girls with acute lymphoblastic leukemia (ALL) whose leukemia cells were near-haploid. Their lymphoblasts stained in a block pattern with periodic acid Schiff and had “common ALL” surface markers confirmed by indirect immunofluorescence. Each patient had two populations of blasts, one near-haploid and one hyperdiploid, which was an exact doubling of the near-haploid karyotype. The first patient had a predominant population of cells with 26 chromosomes and a few with 52, while the second had a predominance of cells with 56 and a minority with 28. Flow cytometric analysis of DNA content initially detected the minor near-haploid population in the second patient, which was confirmed later by cytogenetic review of the marrow sample. In addition to our two patients, only four patients have been reported with near-haploid ALL. Of these six, five were girls, five were adolescents, and five had short survivals (median, 10 mo). All six had disomy of chromosome 21 with or without disomy for chromosomes 10, 14, 18, or X (four patients each). Thus, near-haploid ALL may represent a unique subgroup of ALL with a poor prognosis. To detect these and other possible subgroups, we have included cytogenetic analysis and flow cytometric analysis of DNA content in our initial evaluation of patients with ALL.


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