The Ultrastructure of Skeletal Muscle Capillaries of Streptozotocin Diabetic Rats and the Therapeutic Effect of Benfluorex.

Diabetes mellitus is a serious disease worldwide and causes other associated diseases. In this study, we observed the effect of streptozotocin (STZ)-induced diabetes and benfluorex treatment on muscular capillary ultrastructure. Adult male rats were used as the test subjects and each individual was intraperitoneally injected with one dose of STZ (45 mg/kg) to induce diabetes. Doses (50 mg/kg) of benfluorex were given to the subjects with tap water by intragastric gavage application once daily for 21 days. At the end of day 21, muscle tissues were obtained from animals and examined under transmission electron microscopy. From the data obtained with the electron microscope, it was observed that the control group had typical continuous capillary vascular structures in their muscles, while STZ caused disruptive disorder of the muscle cells in the capillary wall of the STZ-diabetic group. Additionally, the thickening of the basement membrane around endothelial cells, loss of mitochondrial crista in the muscle cells, enlarged endothelial cells, and narrowed vessel lumen were observed in the muscle tissue. The findings of our study revealed that STZ-induced diabetes disrupted the vascular structure, while benfluorex partially improved it.

Efficacy and safety of papaverine as an in vitro motility enhancer on human spermatozoa.

PURPOSE: The aim of this study was to examine the ability and safety of papaverine supplementation for in vitro sperm motility enhancement. In addition, sperm motility enhancement of papaverine was compared to pentoxifylline and theophylline. The post-thaw spermatozoa were used as an asthenozoospermia model. METHODS: Post thaw sperm suspensions were divided into two groups: papaverine (100 µmol/L) and control, and each was investigated in two subgroups of 30- and 60-min exposure times. Detailed motility parameters were detected using a computerized sperm motility analyzer. Acrosomal status, viability, apoptosis, and DNA fragmentation were evaluated by flow cytometry. Furthermore, the motility-enhancing capacity of papaverine, pentoxifylline, and theophylline was compared. RESULTS: Cryopreservation impaired sperm parameters dramatically but no significant changes occurred in acrosomal status and apoptosis. Supplementation of papaverine enhanced motility parameters consistently at all exposure intervals, significantly. However, viability was lower at the 60th minute compared to the 30th minute (p=0.019). Papaverine did not alter any acrosomal or apoptotic markers at any time points. All of the compounds compared in this study increased the motility parameters, where theophylline supplementation provided significantly better improvement in total motility compared to papaverine and pentoxifylline. CONCLUSION: Our results suggest that in vitro papaverine treatment for 30 min adequately improves motility of post-thaw sperm, without leading to acrosome reaction, DNA damage, and viability loss. Theophylline's potency on increasing the ratio of total motile spermatozoa was found significantly superior than the two tested compounds. Prospective clinical studies with embryo production, pregnancy, and live birth data should be undertaken.

Ultrastructural Alterations of Liver Tissue Cells in Methotrexate-Treated Balb/c Mice.

AIM: The current study investigated the efficacy of methotrexate (MTX) on liver tissue cells of Balb/c mice at the ultrastructural level using transmission electron microscopy. BACKGROUND: This agent is well known and used as a chemotherapeutic agent for a long time and not selective for cancer cells so, healthy cells beside cancer cells are also affected by MTX. MATERIALS AND METHODS: Experimental animals were divided into two groups; the first group was kept without treatment and served as the control, the second group was treated with 115 mg/kg MTX i.p. once weekly for 4 weeks and sacrificed under anesthesia after the 4th week. The liver tissues were osmium fixed and embedded in araldite, sectioned and observed under transmission electron microscope. RESULTS: Normal cell ultrastructure was determined in the control group whereas the liver cells of the MTX-treated group revealed ultrastructural alterations, such as the increase in lipid droplets, discontinuity of rough endoplasmic reticulum cisternae and vacuole formation. In addition, the loss of cytoplasmic material in hepatocytes was also evident. Condensation of nuclear chromatin and fusion of nucleic membranes were observed in the liver cells of the treated group. CONCLUSIONS: Results of the study indicated that MTX, used for different types of medical treatment, disturbed liver cell ultrastructure.

Comparison of the effects of difenacoum and brodifacoum on the ultrastructure of rat liver cells.

We used transmission electron microscopy to examine the cytotoxic effects of the second-generation anticoagulant rodenticides difenacoum and brodifacoum on rat liver. A single dose of difenacoum or brodifacoum was administered to rats by gastric gavage and liver samples were taken after 24 h, four days or seven days. In the livers of rats treated with difenacoum for 24 h, hepatocytes typically showed increased numbers of lysosomes, as well as enlargement of both the perinuclear space and the cisternae of the rough endoplasmic reticulum (RER), while sinusoids were irregularly shaped and contained Kupffer cells. Similar irregularities occurred in brodifacoum-treated rats at the same time point, but additionally increased numbers of vacuoles, damaged mitochondrial cristae, and clumping of chromatin were observed in hepatocytes, and hemolysed erythrocytes were noted in the sinusoids. Comparable findings were made in each group of rats after four days. After seven days of difenacoum treatment, hepatocytes suffered loss of cytoplasmic material and mitochondrial shrinkage, while RER cisternae became discontinuous. In contrast, exposure to brodifacoum for seven days caused the formation of numerous vacuoles and lipid droplets, disordered mitochondrial morphology, chromatin clumping and invagination of the nuclear envelope in hepatocytes. Sinusoids in the livers of rodenticide-treated rats contained an accumulation of dense material, lipid droplets, cells with pycnotic nuclei and hemolysed erythrocytes. Overall, our results show that brodifacoum causes more severe effects in liver cells than difenacoum. Thus our microscopic data along with additional biochemical assays point to a severe effect of rodenticide on vertebrates.

An ultrastructural study, effects of Proteus vulgaris OX19 on the rabbit spleen cells.

Effects of Proteus vulgaris OX19 on the spleen cells of rabbits were investigated. Control group (n=5) and Proteus treated group (n=5) of New Zealand male rabbits were used in this study. Bacteria were injected to the rabbits in five days periods with increasing dosages for one month. Thin sections were examined by transmission electron microscope (Jeol 100CXII). Ultrastructural changes were defined in spleen tissue cells due to the antigenic stimulation of bacteria. Spleen cells observed in control group were in normal structure and cells were in close contact with each other. However, spleen cells of Proteus treated group displayed structural changes with regard to the control group in electron microscopic examinations. Chemotaxis of macrophages, forming of pseudopodia and presence of phagocytic vacuoles were observed. Lymphocytes, the major cells of spleen revealed mitotic activity. In addition, chromatin condensation in nucleus and dilatations in perinuclear space were significant. Interactions of lymphocytes and macrophages were noteworthy.

Evaluation of patulin toxicity in the thymus of growing male rats.

Patulin is a mycotoxin produced by several Penicillium, Aspergillus, and Byssachlamys species growing on food products. In this study, we investigated the effects of patulin on the thymus of growing male rats aged five to six weeks. The rats were receiving it orally at a dose of 0.1 mg kg-1 bw a day for either 60 or 90 days. At the end of the experiment, the thymus was examined for histopathology by light microscopy and for epidermal growth factor (EGF) and its receptor (EGFR) by immunolocalisation. For morphometry we used the Bs200prop program to analyse images obtained with the Olympus BX51 light microscope. Cell ultrastructure was studied by electron microscopy. In rats treated with patulin, the thymus showed haemorrhage, plasma cell hyperplasia, a dilation and fibrosis in the cortex, enlarged interstitial tissue between the thymic lobules, enlarged fat tissue, thinning of the cortex, and blurring of the cortico-medullary demarcation. Electron microscopy showed signs of cell destruction, abnormalities of the nucleus and organelles, and loss of mitochondrial cristae. However, no differences were observed in thymus EGF and EGFR immunoreactivity between treated and control rats.

Effect of patulin on the interdigitating dendritic cells (IDCs) of rat thymus.

Patulin is a common fungal contaminant of ripe apples used for the production of apple juice concentrates and it is also present in other fruits, vegetables and food products. Patulin is a secondary metabolite produced by species of the genera Penicillium, Aspergillus and Byssochlamys. Patulin has been reported to be mutagenic, carcinogenic and teratogenic. Antigen-presenting cells (APCs) are of prime importance in the innate immune response; they capture antigen in tissues and then migrate to the lymphoid organs to present the antigen to T lymphocytes. Thus, they are crucial for the initiation of immunity. Interdigitating dendritic cells (IDCs) are a subset of APCs that are present at the lymphatic organs. In the thymus, they act in positive and negative selection during T cell development. In the present study, patulin was administered orally to growing male rats aged 5-6 weeks. A dose of 0.1 mg kg(-1) bw day(-1) was given to rats for a period of 60 or 90 days daily. The effect of patulin on the IDCs of thymus was investigated by transmission electron microscopy (TEM), and the results were evaluated in terms of cell destruction. In the rats of the control group, it was observed that the IDCs had an indented nucleus, a clear cytoplasm and numerous membrane extensions. In the cytoplasm, a well-developed golgi complex, mitochondria, granular endoplasmic reticulum and a small number of lysosomal structures were observed. At day 60 of patulin-treated rat groups (P-60), loss of cristae in mitochondria and chromatin margination and lysis in the nucleus were found. It was observed that the IDCs had a perinuclear area of cytoplasm surrounded by a peripheral electron-lucent zone. In the cytoplasm of the 90-day patulin-treated rat group (P-90), a peripheral electron-lucent zone was also found, similar to the P-60 group. Additionally increase in vesicular and lysosomal structures, increase in apoptotic bodies and condensation of chromatin in the nucleus were noted. It was observed that patulin leads to apoptotic body formation and cell apoptosis in the IDCs of rat thymus especially in the P-90-treated groups.

Effects of patulin on thymus capillary of rats.

Patulin is a mycotoxin that is produced by species of Penicillum, Aspergillus, and Byssochylamys molds that may grow on a variety of foods including fruit, grains and cheese. Patulin, at a dose of 0.1 mg kg(-1) bw day(-1) was administered orally to growing male rats aged 5-6 weeks for a period of 60 or 90 days. The dose of patulin used in the present study was based on estimated human exposure levels. At the end of these periods, the thymus glands of patulin-treated and control Wistar rats were removed and ultrastructural changes in capillary cells of the thymus of patulin-treated Wistar rats were determined by electron microscopy. The walls of thymus capillaries of the 60-day patulin-treated rat groups (P-60) exhibited degeneration observable in electron microscopic sections. For example, loss of cytoplasm and mitochondrial cristae of cells, swollen endothelial cells, increased thickness of the basement membrane, closed lumen of capillaries, accumulation of fibrous material at the periphery of the capillaries and nuclear anomalies were seen in these sections. Such degeneration and changes were also observed in sections of capillaries of the 90-day patulin-treated rat groups (P-90). The levels of degeneration of endothelial cell nucleus of P-90 were greater than those of P-60. This study demonstrated the ultrastructural degeneration of thymus capillary cells of patulin-treated rats. The results obtained from this study may provide a guide to research dealing with the toxic effects of patulin on tissue and organ ultrastructure.

Ultrastructural determination of gingival Langerhans cells in alloxan-induced diabetic rats.

The ultrastructure of Langerhans cells has not been fully investigated in diabetes-associated gingival tissues. The present study was carried out to investigate the ultrastructure of gingival Langerhans cells in alloxan-induced diabetic rats. Gingival biopsies were obtained from 22 diabetic and 18 control rats. Langerhans cells were observed by transmission electron microscopy (TEM) in the basal layers of healthy oral epithelium. On rare occasions, Langerhans cells were found in the suprabasal layers of the oral epithelium. Langerhans cells in the oral epithelium of diabetic rats were seen in the basal and suprabasal layers. Usually, Langerhans cells had clear cytoplasm and convoluted or indented nuclei and few or no specific granules. The clear cytoplasm contained mitochondria, lysosomes and a small number of rough-surfaced endoplasmic reticulum regions, but it lacked tonofilament. Occasionally, centrioles were also observed in the cytoplasm. The membrane of Langerhans cells had no junctional complexes such as desmosomes. In diabetic rats, Langerhans cell precursors were developed into specific granule-bearing cells. Both Langerhans cells and their granules were more frequent in the gingiva of diabetic rats than in the control group. These data suggest that Langerhans cells play an important role in explaining the pathogenesis and development of diabetic gingivitis.

Characterization of the ultrastructure of gingival mast cells in alloxan-induced diabetic rats.

The morphological changes of gingival mast cells of alloxan-induced diabetic rats were studied by electron microscopy. The following observations were made. The cell nucleus and cytoplasm degenerated. The electron density of the granules in the cell cytoplasm clearly decreased. Some granules had dense irregular threads and the granules were surrounded by a thin vacuole. A ghost vacuole formed in some mast cells and disorganized materials accumulated in the cytoplasm. The mast cell nuclei were generally irregular and degenerating mast cells had pyknotic nuclei. General destruction of the cell membrane and granule shedding in some samples was noted and mitochondria with atypical cristae in the cytoplasm of the mast cells were seen. We conclude that the characteristics of the ultrastructure of gingival mast cells in diabetics are distinctive and should be used as criteria for pathogenesis of gingival inflammation.

Juvenile colloid milium associated with conjunctival and gingival involvement.

Juvenile colloid milium is an uncommon cutaneous disease characterized by translucent papules distributed on sun-exposed areas with early onset. Association of juvenile colloid milium with conjunctival and gingival deposits is uncommon and interesting. We report a case of juvenile colloid milium associated with conjunctival and gingivai deposits of an amyloid-like homogeneous eosinophilic material. It seems that all 3 of these in our patient may be different expressions of the same pathologic disease.

The ultrastructure of the capillaries in the gingiva of alloxan-induced diabetic rats.

The diabetic effects of alloxan (type I diabetes mellitus) were investigated in 40 Wistar albino rats (18 controls and 22 diabetics). Alloxan in sterile physiological saline was injected into animals intravenously. After the induction of diabetes with alloxan, the ultrastructure of the capillaries in the gingiva was examined by transmission electron microscopy. The thickness of the basement membranes was observed closely adherent to the endothelial cells of the capillary alloxan-diabetic rats. It was greatly thickened owing to the increase in its amorphous, granular and filamentous material with occasional scattered collagen fibres. In some sections, the capillary lumens of the diabetics were closed by epithelial cells. Loss of cytoplasmic material and hyalinization were seen in some smooth muscle cells. In addition, the mitochondrial cristae of smooth muscle cell and epithelial cells disappeared. There was endothelial integrity throughout the smooth muscle cells.

Effects of chronic alcohol consumption on myocardial ischemia in rats.

The effects of chronic alcohol consumption on myocardial ischemia and gas perfusion with 95% O(2)-5% CO(2) were investigated in isolated rat heart. Eighteen adult male Wistar rats were used. Rats were assigned into six groups for each group to contain three rats: normal, alcoholic, normal ischemic, alcoholic ischemic, normal ischemic and 95% O(2)-5% CO(2) perfused, alcoholic ischemic and 95% O(2)-5% CO(2) perfused, respectively. Alcohol (7.2%, v/v) was given to rats by a modified liquid diet for 21 days. Rats were anaesthetized with ketamine (1-2mg kg(-1)). Hearts were quickly isolated. Normal and alcoholic rat hearts were directly sent to the electron microscopic preparation. The other hearts were cut into small pieces and put into Krebs solution. The solution was continuously bubbled using 95% N(2)-5% CO(2) 20 min for ischemia. After removal of normal ischemic and alcoholic ischemic heart specimens for electron microscopic examination, the remaining hearts of the last two groups were bubbled with 95% O(2)-5% CO(2) for another 20 min for the purpose of reperfusion and then were also prepared for electron microscopic examination. The hearts were investigated with a transmission electron microscope (Jeol 100 CXII TEM). Twenty-one days of chronic alcohol consumption was found to have no significant effect on myocardial ischemia determined by transmission electron microscopic examination. Our results suggest that there is no significant relationship between 21 days of alcohol consumption by a liquid diet and myocardial protection.