Bulunan: 45 Adet 0.003 sn
Koleksiyon [13]
Tam Metin [2]
Yayın Türü [3]
Yazar [20]
Yayın Yılı [19]
Tez Danışmanı [2]
Konu Başlıkları [19]
Yayıncı [18]
Yayın Dili [3]
Dergi Adı [20]
Light and electron microscopic examination of pineal gland in rats exposed to constant light and constant darkness

Kus I. | Sarsilmaz M. | Ozen O.A. | Turkoglu A.O. | Pekmez H. | Songur A. | Kelestimur H.

Makale | 2004 | Neuroendocrinology Letters25 ( 01.Feb ) , pp.102 - 108

OBJECTIVE: This study was aimed to examine the pineal gland of rats exposed to constant light and darkness at light and electron microscopic level. DESIGN: For this purpose 18 male Wistar rats were used. Animals were divided into three groups. Rats in group I (Control) were kept under 12 hrs light: 12 hrs dark conditions. Rats in group II were exposed to constant darkness, while rats in group III were exposed to constant light for 6 weeks. At the end of the experiment, all animals were killed by decapitation. The pineal glands of rats were removed, then processed for light and electron microscopy. RESULTS: In our study, extensive nu . . .mber of pinealocytes was observed in the structure of pineal gland of rats exposed to constant darkness and some of the observed pinealocytes were determined to contain double nucleoli. Furthermore, mitochondria and lipid droplets in the cytoplasm of pinealocytes were increased and rough endoplasmic reticulum sacs were enlarged in this group. Whereas, in rats those exposed to the constant light, a decrease in pinealocyte intensity was associated with increase in the connective tissue between parenchymal cells. Additionally, mitochondria and lipid droplets in the cytoplasm of cells were decreased. CONCLUSIONS: It was observed that the pinealocyte cell activity of rats exposed to constant darkness was increased but decreased in rats exposed to constant light. Copyright © Neuroendocrinology Letters Daha fazlası Daha az

Stereological evaluation of local administered palmatine on bone regeneration [Lokal olarak uygulanan palmatinin kemik rejenerasyonuna etkisinin stereolojik olarak incelenmesi]

Türer Ç.C. | Türer A.

Makale | 2017 | Journal of Clinical and Analytical Medicine8 ( 6 ) , pp.478 - 481

Aim: The purpose of this study is to investigate the healing potential of the local administration of palmatine on autogenous grafted critical-sized cortical bone defects. Material and Method: Twenty-four rats were divided into three groups: Group C (passive control), Group G (active control) and Group G+PLM. A 5-mm diameter critical-size defect was created in the calvarium of each animal. In Group C, the defects were left empty. In Group G defects were filled with only autogenous graft and an absorbable collagen sponge treated with 300 mg sterile saline solution was applied on grafted area. In Group G+PLM defects were filled with a . . .utogenous graft, and 300 mg palmatine treated absorbable collagen sponge was applied on grafted area. All animals were euthanized at 28 days postoperative. Stereologic analyses were performed. New bone volume and connective tissue volumes were measured. Results: Stereologic analysis showed that Group G and G+PLM significantly had more new bone at four weeks compared with group C. Connective tissue volumes were also significantly higher in autografted groups. New bone and connective tissue volumes’ difference were not statistically significant between group G and G+PLM groups. Discussion: Locally administered 500 mg palmatine doesn’t enhance bone regeneration in critical size calvarial rat defects filled with autologous graft. © 2017, Derman Medical Publishing. All rights reserved Daha fazlası Daha az

Effects of estradiol benzoate on the ultrastructure of the pinealocyte in the ovariectomized rat

Kus I. | Oner H. | Ozogul C. | Ayar A. | Ozen O.A. | Sarsilmaz M. | Kelestimur H.

Makale | 2002 | Neuroendocrinology Letters23 ( 05.Jun ) , pp.405 - 410

Objective: The aim of this study was to examine the effects of ovariectomy and ovariectomy followed by estradiol benzoate administration on the ultrastructure of pinealocytes in female rat. Design: For this purpose 15 female Wistar rats were used. Animals were divided into three groups. Group I and II were designated as sham-ovariectomized (control) and ovariectomized, respectively. Group III was ovariectomized and daily injected with estradiol benzoate for one month. At the end of the experiment, all animals were anesthetized with ketamine for fixation by vascular perfusion. Pineal glands of groups I, II and III were removed. All s . . .pecimens were examined by electron microscopy. Results: Ovariectomy caused an increase of lipid droplets, mitochondria and ribosomes. Rough endoplasmic reticulum was extensive in the cytoplasm. Estradiol administration to ovariectomized rats resulted in formation of less extensive lipid droplets, mitochondria and ribosomes compared to pinealocyte ultrastructure of both control and ovariectomized rats. Extensiveness of rough endoplasmic reticulum in the pinealocytes of estradiol-administrated rats was similar to that in controls. Conclusions: The results confirm relationship between the pineal gland and gonads in the rat and it has been suggested that estradiol benzoate reverses the ultrastructural changes, which indicate increased cell activation, occurring in the pinealocytes after ovariectomy Daha fazlası Daha az

The effects of oral administration of Aloe vera [barbadensis] on rat central nervous system: An experimental preliminary study

Kosif R. | Aktas R.G. | Oztekin A.

Makale | 2008 | Neuroanatomy7 , pp.22 - 27

Aloe vera [barbadensis] (Av) is widely used for both commercial and therapeutic purposes. It has been used for an array of ailments since ancient times as a medicinal plant. There are more than 360 diffcrent species of Av. Its products have been used in health foods for medical and preservative purposes. The objective of this study was to investigate the effects of Av on the rat's central nervous system; since there are limited studies on that issue. Gel form of Av is used in the study. It is commercial, preserved but otherwise untreated form of Av. Female Wistar Albino rats were divided into three study groups. Tissue specimens fro . . .m cerebrum, cerebellum, hippocampus and ventricular area were processed for the microscopic examination. All sections from each group were stained with hematoxylin eosin and cresyl violet. Our results indicate that Av did not have any clear toxic effects on both neurons and glial cells of the central nervous system in different areas. Cytoplasmic features of the neurons, Nissle bodies, axonal hillock, and nuclei of neurons were the same after the treatment. However; the relationship between the Purkinje cells and the surrounding cerebellar tissue was decreased in the treated group. The other important finding was the change of ependymal cells at the ventricular zone: The number and the height of these cells were obviously increased. The single layered epithelium changed into the stratified epithelium in certain areas. It was also evident that microvilli and the cilia on the apical side of these cell increased dramatically. The capillaries in the region of choroid plexus were also dramatically increased. We believe that further studies related with these morphological changes will be helpful to understand the mechanism(s) of the similar transformation of the cells in different conditions. © Neuroanatomy Daha fazlası Daha az

The effects of photoperiod on testes in rat: A morphometric and immunohistochemical study

Kus I. | Akpolat N. | Oner H. | Ayar A. | Pekmez H. | Ozen O.A. | Sarsilmaz M.

Makale | 2003 | Neuroendocrinology Letters24 ( 03.Apr ) , pp.209 - 214

Objective: The aim of this study was to examine the effects of photoperiod on testes in rat. Design: For this purpose 21 male Wistar rats were used. Animals were divided into three groups. Control rats in group I were kept under 12 hrs light: 12 hrs dark conditions (12L: 12D) for 10 weeks. Animals in group II were exposed to long photoperiods (18L: 6D), while rats in group III were exposed to short photoperiods (6L: 18D) for 10 weeks. At the end of the experiment, all animals were killed by decapitation and blood samples were obtained. Serum testosterone levels were determined with the use of a chemiluminescent enzyme immunoassay. T . . .he testes of all rats were removed and weighed. Testicular tissue was processed semiquantitative evaluation of immunohistochemical testosterone staining. Intensity of immunostaining was determined on a scale between 0 (no staining) and 5 (heavy staining). For morphometric comparison, diameters of seminiferous tubules in each group were measured. Results: In rats exposed to long photoperiods, testicular weights, diameters of seminiferous tubules and serum testosterone levels were significantly increased as compared to those in control rats. Whereas, exposure of rats to short photoperiods resulted in significantly decrease of testicular weights, diameters of seminiferous tubules and serum testosterone levels as compared to those in control rats and rats maintained in long photoperiods. Immunostaining of testosterone was moderate (3+) in control rats, heavy (5+) in rats exposed to long photoperiods and minimal (1+) in rats exposed to short photoperiods. Conclusions: The results of our study indicate that testicular functions increase after exposure to long photoperiods and decrease after exposure to short photoperiods Daha fazlası Daha az

Detailed spectral profile analysis of penicillin-induced epileptiform activity in anesthetized rats

Canan S. | Ankarali S. | Marangoz C.

Makale | 2008 | Epilepsy Research82 ( 1 ) , pp.7 - 14

Penicillin model is a widely used experimental model for epilepsy research. In the present study we aimed to portray a detailed spectral analysis of penicillin-induced epileptiform activity in comparison with basal brain activity in anesthetized Wistar rats. Male Wistar rats were anesthetized with i.p. urethane and connected to an electrocorticogram setup. After a short period of basal activity recording, epileptic focus was induced by injecting 400 IU/2 µl penicillin-G potassium into the left lateral ventricle while the cortical activity was continuously recorded. Basal activity, latent period and the penicillin-induced epileptifor . . .m activity periods were then analyzed using both conventional methods and spectral analysis. Spectral analyses were conducted by dividing the whole spectrum into different frequency bands including delta, theta (slow and fast), alpha-sigma, beta (1 and 2) and gamma (1 and 2) bands. Our results show that the most affected frequency bands were delta, theta, beta-2 and gamma-2 bands during the epileptiform activity and there were marked differences in terms of spectral densities between three investigated episodes (basal activity, latent period and epileptiform activity). Our results may help to analyze novel data obtained using similar experimental models and the simple analysis method described here can be used in similar studies to investigate the basic neuronal mechanism of this or other types of experimental epilepsies. © 2008 Elsevier B.V. All rights reserved Daha fazlası Daha az

Neuroprotective effects of rosuvastatin against traumatic spinal cord injury in rats

Kahveci R. | Gökçe E.C. | Gürer B. | Gökçe A. | Kisa U. | Cemil D.B. | Sargon M.F.

Makale | 2014 | European Journal of Pharmacology741 , pp.45 - 54

Rosuvastatin, which is a potent statin, has never been studied in traumatic spinal cord injury. The aim of this study was to investigate whether rosuvastatin treatment could protect the spinal cord after experimental spinal cord injury. Rats were randomized into the following five groups of eight animals each: control, sham, trauma, rosuvastatin, and methylprednisolone. In the control group, no surgical intervention was performed. In the sham group, only laminectomy was performed. In all the other groups, the spinal cord trauma model was created by the occlusion of the spinal cord with an aneurysm clip. In the spinal cord tissue, ca . . .spase-3 activity, tumor necrosis factor-alpha levels, myeloperoxidase activity, malondialdehyde levels, nitric oxide levels, and superoxide dismutase levels were analyzed. Histopathological and ultrastructural evaluations were also performed. Neurological evaluation was performed using the Basso, Beattie, and Bresnahan locomotor scale and the inclined-plane test.After traumatic spinal cord injury, increases in caspase-3 activity, tumor necrosis factor-alpha levels, myeloperoxidase activity, malondialdehyde levels, and nitric oxide levels were detected. In contrast, the superoxide dismutase levels were decreased. After the administration of rosuvastatin, decreases were observed in the tissue caspase-3 activity, tumor necrosis factor-alpha levels, myeloperoxidase activity, malondialdehyde levels, and nitric oxide levels. In contrast, tissue superoxide dismutase levels were increased. Furthermore, rosuvastatin treatment showed improved results concerning the histopathological scores, the ultrastructural score and the functional tests. Biochemical, histopathological, ultrastructural analysis and functional tests revealed that rosuvastatin exhibits meaningful neuroprotective effects against spinal cord injury. © 2014 Elsevier B.V Daha fazlası Daha az

Sexual dependency of rat sciatic nerve fiber conduction velocity distributions

Ayaz M. | Kiziltan E. | Tuncer S. | Dalkilic N. | Demirel I. | Bariskaner H. | Pehlivan F.

Makale | 2007 | International Journal of Neuroscience117 ( 11 ) , pp.1537 - 1549

Gender differences, either with the structural or through with hormones, dictate how the corresponding organ or organ system responses to physiological signals. Current study aims to investigate gender dependent differences in conduction related parameters of rat sciatic nerve. Compound action potentials (CAP) were recorded via suction electrode whereas the conduction velocity distributions (CVD) were performed using the method known as collision technique in the literature. Studied CAP parameters, namely conduction velocities (CV), area of the CAPs and time required to reach the maximum depolarization (TP) have been found significa . . .ntly different for female and male rats. Detailed analyses have shown that sex dependent differences were more remarkable in the right leg responses of female and male rats. Additionally, CVDs indicate that the number of fibers having CVs between 5-30 m/s is much more in male right sciatic nerve trunk when compared to age matched female rats. The present study, for the first time clearly shows that shift in the contribution of nerve fibers to lower CVs is the main causal of the sex dependent differences seen in rat sciatic nerve fibers. Copyright © 2007 Informa Healthcare USA, Inc Daha fazlası Daha az

Effect of thyroidectomy on the histology of rat sublingual gland

Oncu M. | Kanter M. | Gokcimen A. | Kavakli D. | Oncu M. | Ural M. | Karaoz E.

Makale | 2004 | APMIS112 ( 2 ) , pp.119 - 122

This study was carried out to investigate the effect of thyroidectomy on the histology of rat sublingual gland. Twenty-eight male Wistar albino rats, aged 4 weeks and weighing between 45-55 g, were used. The rats were divided into two experimental groups (control and thyroidectomy), each containing 14 animals. Total thyroidectomy of rats was performed under ether anesthesia in thyroidectomy group. The rats in the control group were sham operated without having the thyroidectomy. Seven rats randomly selected from both groups were fixed using the perfusion fixation technique 2 and 6 weeks after thyroidectomy, and their sublingual glan . . .ds were harvested for histological investigation. No histological difference was observed between the two groups 2 weeks after thyroidectomy. However, 6 weeks after thyroidectomy considerable cytoplasmic vacuolization of the epithelial cells of the mucous tubules was seen in the thyroidectomy group compared to the controls. Enlargement of mucous tubules was also observed, and the lumina in most of the tubules was quite dilated. In the stroma surrounding the parenchymal tissues, increased lipid tissue mass was observed. In addition, increased connective tissue mass and mononuclear cell infiltrations were evident. Furthermore, the number of mast cells was significantly higher in the thyroidectomy group than in the controls 6 weeks after thyroidectomy. It was concluded that the thyroid gland and hormones might have an influence on the histology of the sublingual gland Daha fazlası Daha az

The effects of bortezomib on the ovariectomy applied rat uterus: A histopathological, stereological, and immunohistochemical study

Khoshvaghti H. | Altunkaynak B.Z.

Makale | 2018 | Iranian Journal of Basic Medical Sciences21 ( 11 ) , pp.1118 - 1125

Objective(s): In this study, potential protective effects of Bortezomib (Bort), as a proteasome inhibitor, were investigated on the uterus of ovariectomized rats by histological, morphometric and immunohistochemical methods. Materials and Methods: In this study, 18 Sprague dawley strain female rats (12 weeks old, 250-300 g body weight) were used. Animals in the control group (Cont, n=6) were not exposed to any treatment. Ovariectomy was performed on the experimental groups. They (n=12) were divided into ovariectomy (Ovt, n=6) and Bortezomib (Bort, n=6) subgroups. Twelve weeks later, the rats were perfused. Then, uterine tissues were . . . removed and examined by morphometrical, and light and electron microscopy methods. In addition, immunoreactivity of nuclear factor-kappa (NF-?B) was evaluated. Results: Morphometric and histopathological evaluations showed that Bort was effective in the uterus and protects the layer structures and the cells. Conclusion: In the light of these findings, we suggest that for proteasome inhibitor particularly Bort is thought to be useful through proteasome inhibition and NF-?B pathway. © 2018, Mashhad University of Medical Sciences. All rights reserved Daha fazlası Daha az

Gastroprotective activity of Nigella sativa L oil and its constituent, thymoquinone against acute alcohol-induced gastric mucosal injury in rats

Kanter, Mehmet | Demir, Halit | Karakaya, Cengiz | Ozbek, Hanefi

Makale | 2005 | WORLD JOURNAL OF GASTROENTEROLOGY11 ( 42 ) , pp.6662 - 6666

AIM: To evaluate the role of reactive oxygen species in the pathogenesis of acute ethanol-induced gastric mucosal lesions and the effect of Nigella sativa L oil (NS) and its constituent thymoquinone (TQ) in an experimental model. METHODS: Male Wistar albino rats were assigned into 4 groups. Control group was given physiologic saline orally (10 mL/kg body weight) as the vehicle (gavage); ethanol group was administrated 1 mL (per rat) absolute alcohol by gavage; the third and fourth groups were given NS (10 mL/kg body weight) and TQ (10 mg/kg body weight p.o) respectively 1 h prior to alcohol intake. One hour after ethanol administrat . . .ion, stomach tissues were excised for macroscopic examination and biochemical analysis. RESULTS: NS and TQ could protect gastric mucosa against the injurious effect of absolute alcohol and promote ulcer healing as evidenced from the ulcer index (UI) values. NS prevented alcohol-induced increase in thiobarbituric acid-reactive substances (TBARS), an index of lipid peroxidation. NS also increased gastric glutathione content (GSH), enzymatic activities of gastric superoxide dismutase (SOD) and glutathione-S-transferase (GST). Likewise, TQ protected against the ulcerating effect of alcohol and mitigated most of the biochemical adverse effects induced by alcohol in gastric mucosa, but to a lesser extent than NS. Neither NS nor TQ affected catalase activity in gastric tissue. CONCLUSION: Both NS and TQ, particularly NS can partly protect gastric mucosa from acute alcohol-induced mucosal injury, and these gastroprotective effects might be induced, at least partly by their radical scavenging activity. (C) 2005 The WJG Press and Elsevier Inc. All rights reserved Daha fazlası Daha az

Effects of human placental amnion derived mesenchymal stem cells on proliferation and apoptosis mechanisms in chronic kidney disease in the rat

Cetinkaya B. | Unek G. | Kipmen-Korgun D. | Koksoy S. | Korgun E.T.

Makale | 2019 | International Journal of Stem Cells12 ( 1 ) , pp.151 - 161

Background and Objectives: The feature of chronic kidney failure (CKF) is loss of kidney functions due to erosion of healthy tissue and fibrosis. Recent studies showed that Mesenchymal stem cells (MSCs) differentiated into tubular epithelial cells thus renal function and structures renewed.Furthermore, MSCs protect renal function in CKF. Therefore, we aimed to investigate whether human amnion-derived mesenchymal stem cells (hAMSCs) can repair fibrosis and determine the effects on proliferation and apoptosis mechanisms in chronic kidney failure. Methods and Results: In this study, rat model of CKF was constituted by applying Aristolo . . .chic acid (AA). hAMSCs were isolated from term placenta amnion membrane and transplanted into tail vein of rats. At the end of 30 days and 60 days of recovery period, we examined expressions of PCNA, p57 and Parp-1 by western blotting. Immunoreactivity of PCNA, Ki67, IL-6 and Collagen type I were detected by immunohistochemistry. Besides, apoptosis was detected by TUNEL. Serum creatinine and urea were measured. Expressions of PCNA and Ki67 increased in hAMSC groups compared with AA group. Furthermore, expressions of PARP-1 apoptosis marker and p57 cell cycle inhibitory protein increased in AA group significantly according to control, hAMSC groups and sham groups. IL-6 proinflammatory cytokine increased in AA group significantly according to control, hAMSCs groups and sham groups. Expressions of Collagen type I protein reduced in hAMSCs groups compared to AA group. After hAMSC treatment, serum creatinine and urea levels significantly decreased compared to AA group. After injection of hAMSC to rats, Masson's Trichrome and Sirius Red staining showed fibrosis reduction in kidney. Conclusions: According to our results hAMSCs can be ameliorate renal failure. © 2019 by the Korean Society for Stem Cell Research Daha fazlası Daha az

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