Biomedical subjects

Sevinc Inan

Publications and source records attributed to Sevinc Inan.

8 recordsLinked to original sources

PubMed2006

Histophysiological effects of fluid resuscitation on heart, lung and brain tissues in rats with hypovolemia.

The efficacy of using colloids and crystalloids in the treatment of hypovolemia still remains controversial. An important aspect in treating hypovolemia is to re-establish normal tissue hemodynamics after fluid resuscitation. Production of nitric oxide (NO) or growth factors such as transforming growth factor beta (TGF-beta) has been identified as a key mechanism in physiological and pathological processes in the different systems. This study was designed to investigate the histophysiological effects of resuscitation with different plasma substitutes on the heart, lung and brain tissues following acute blood loss in male Sprague-Dawley rats weighing 250-280g (n=30). After anesthesia with sodium pentobarbital, the left femoral vein and artery were cannulated for the administration of volume expanders and for direct measurement of arterial pressure and heart rate. Twenty rats were bled (5ml/10min) and infused (5ml/10min) with one of four randomly selected solutions, (a) human albumin, (b) gelatin (Gelofusine), (c) dextran-70 (Macrodex); or (d) physiological saline (0.9% isotonic saline). Five control rats were bled without infusion. Tissue samples were taken and fixed in 10% formalin solution, then processed for embedding in paraffin wax. Sections were cut and stained with hematoxylin and eosin. Indirect immunohistochemical labelling was performed to reveal binding of primary antibodies against endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS) and TGF-beta. Mild immunoreactivity of eNOS was observed in endothelial cells of vessels in brain, heart and lung tissues. Increased immunoreactivities of eNOS, iNOS and TGF-beta were observed in the non-fluid resuscitated group in these organs; mild, moderate, moderate and strong immunoreactivities were seen in the albumin, gelatin, physiological saline and dextran-70 treated groups, respectively. Immunoreactivities of iNOS and TGF-beta in the non-fluid resuscitated group were increased significantly, in comparison to the other groups, apart from the dextran-70 treated group. The results of this study show that gelatin solution and physiological saline may be of use after acute blood loss, and dextran-70 is not the preferred resuscitation fluid in the early stages of acute blood loss. It was concluded that albumin solution is the preferred fluid for resuscitation.

Animals↗

PubMed2006

Histopathological and ultrastructural effects of glycolic acid on rat skin.

Use of alpha hydroxy acids (AHA) to ameliorate specific dermatological problems with keratinization has become fairly widespread. The aim of this study was to evaluate the effects of the AHA derivative of glycolic acid, applied in different dosages, on rat skin using light and electron microscopy. Skin biopsies were taken from the dorsal side of rats (n=16) and at the end of each week after applying solutions containing AHA: week 1, 8% (n=5); week 2, 50% (n=5); week 3, 70% (n=6). The skin samples were fixed in 10% formalin for histology and 2.5% glutaraldehyde solution for electron microscopy and processed using routine protocols. Histological sections were stained with hematoxylin and eosin (H&E), Masson's trichrome and were also labelled for binding of a primary antibody against collagen I using the avidin-biotin-peroxidase method. The epidermal thicknesses were measured and the fibroblast count of the dermis was taken and the results compared using the statistical ANOVA test. Semi-thin sections were stained with toluidine blue-azure II solution and ultrathin sections were contrasted with uranyl acetate and lead citrate. Histochemical and immunohistochemical observations demonstrated that AHA treatment resulted in statistically significant increased thickness of the epidermis and an increase in numbers of active fibroblasts and in the amount of dense collagen, especially at higher dosages of AHA. Ultrastructural examination of rat skin from AHA-treated groups showed cytoplasmic vacuolization in epidermal keratinocytes, intercellular dysjunctions, and increased quantities of organized bundles of collagen fibers in the dermis. The use of AHA in appropriate dosages has been found to play an important role in the treatment of specific skin disorders, however, the harmful effects of use of AHAs at higher concentrations should not be ignored. We conclude that alpha hydroxyl acids have a wide spectrum of use in the field of dermatology but, due to side-effects, their use, dosage, and time frame should be restricted to the advice of dermatologists.

Animals↗

PubMed2005

Histopathological and ultrastructural effects of Losartan on embryonic rat kidney.

The aim of our study was to investigate the histopathological, immunohistochemical and ultrastructural effects of Losartan (a selective angiotensin II type-1 receptor blocker) on renal development in rats. Twelve pregnant rats were divided into control and experimental groups. In the experimental group, Losartan (10 mg/kg/day) was given via nasogastric tube, between the sixth day of implantation and time of sacrifice on embryonic days 18 and 20. All formalin-fixed, paraffin wax-embedded renal tissue sections were stained with hematoxylin and eosin or labelled for binding of primary antibodies against transforming growth factor-beta (TGF-beta 1,-2,-3) using an avidin-biotin-peroxidase method. For electron microscopic examination, samples were fixed with glutaraldehyde and osmium tetroxide and embedded in araldite. Glomerular basement membrane (GBM) thickness was measured and compared using an unpaired t-test. Angiotensin II type-1 receptor antagonism by Losartan inhibited renal growth and delayed nephron maturation. Increased immunoreactivity of TGF-beta's was observed in developing nephron precursors and interstitial cells in the experimental group. Electron microscopical examination showed that thickening of the GBM was normal in the control group but an irregular thickening was seen in the experimental group (p < 0.001). It was also seen that epithelial cells of developing tubules underwent apoptosis in the experimental group. Thus, renal development in rats seems to depend on an intact renin-angiotensin system.

Animals↗

PubMed2004

Immunolocalization of integrins and fibronectin in tubal pregnancy.

Integrins are a large family of cell adhesion molecules that serve as receptors involved in cell-to-cell and cell-to-matrix interactions during implantation. We studied immunohistochemical staining of integrins (alpha 3, alpha V, beta 1, and alpha 2 beta 1) and fibronectin in ectopic tubal pregnancy. Thirty fallopian tube samples with ectopic pregnancies and five normal tubal segments were obtained during ligation operations; the latter specimens served as controls in the study. Formalin-fixed paraffin-embedded tissue sections were stained with hematoxylin-eosin or primary antibodies against alpha 3, beta 1, alpha V, and alpha 2 beta 1 integrins and fibronectin, using the avidin-biotin-peroxidase method. A semi-quantitative grading system was used to compare staining intensities. In the control samples, immunostaining of all integrins was found in a single layer of tall columnar epithelial cells, the lamina propria (Lp) and the muscular layer. Fibronectin staining was detected in the Lp and the muscular layer. Staining intensities of alpha 3 and beta 1 integrins and fibronectin were increased in the normal part of fallopian tubes with ectopic pregnancies. Staining of beta 1 integrin was more intense than staining of alpha 3 and fibronectin, whereas there was no difference in alpha V and alpha 2 beta 1 integrin expression between normal tubal tissue in the ectopic pregnancy group and control tubal tissue. In the tubal pregnancy group at the site of implantation, staining intensity of alpha 3 and beta 1 integrins and fibronectin was strong in decidual cells, supporting tissue and placental villi, whereas alpha V and alpha 2 beta 1 staining was mild. We concluded that integrins, especially beta 1 and alpha 3, and fibronectin may play a role in progression of tubal implantation. Although the role of integrins has not yet been clearly defined, these molecules may function as markers of normal and abnormal states of receptivity. We like to suggest that integrins and fibronectin, which are needed in utero implantation, are expressed in tubal tissues during ectopic pregnancy and are involved in ectopic implantation.

Decidua↗

PubMed2003

The roles of transforming growth factor type beta3 (TGF-beta3) and mast cells in the pathogenesis of scleroderma.

Scleroderma is a connective tissue disorder characterised by excessive accumulation of collagen in the skin and internal organs. The most likely explanation for this process is local activation of collagen synthesis from fibroblasts. Our intention was to elucidate whether TGF-beta3 and mast cells play a pathogenic role in abnormal connective tissue formation in scleroderma. In this study, skin biopsies from 20 patients with scleroderma and five from healthy individuals were studied by an indirect immunoperoxidase technique to determine the immunoreactivity of TGF-beta3 in the dermis. In addition, skin samples were stained with toluidine blue to count the number of mast cells in scleroderma, and tissues were examined under the electron microscope to evaluate the ultrastructural changes. Increased TGF-beta3 immunoreactivities were detected in the dermis in the patient's skin, suggesting the presence of a subpopulation responsible for the increased collagen production. Mast cell counts in the skin of patients with scleroderma were significantly greater (19.2 +/- 4.1/unit) than those of normal controls (4.4 +/- 1.2/unit). Ultrastructural observations indicated that there is a close relationship between the mast cells and fibroblasts. These results suggest that fibrosis in scleroderma could evolve through the activation of fibroblasts and the regulatory mechanisms that appear to modulate the behavior of these cells with respect to collagen production.

Adult↗

PubMed2003

Effect of insulin on rat ovarian leptin expression by immunohistochemical staining.

AIM: Leptin and insulin may interact in regulating ovarian steroid synthesis. The objective of this study was to investigate immunohistochemical staining of leptin in normal rat ovarian tissues and in rats treated with insulin and insulin plus human chorinoic gonadotropin (hCG). METHODS: Paraffin blocks of rat ovarian tissues from a previous study, in which 18 adult, female Wistar rats with an average weight of 250 g were divided into three groups to receive either saline solution, human insulin (2 U/day) or human insulin (2 U/day) plus hCG (4 U/day) for 4 weeks, were used in this study to compare the effects on leptin staining. The results were analysed using a semiquantitative scoring system, such as mild, moderate and strong. RESULTS: No staining was observed in granulosa cells and theca interna cells of normal ovarian tissues. Theca externa cells had mild staining intensity (+), corpus luteum had moderate (+ +) and stroma had mild (+) staining intensity. Histological structure was impaired in the insulin group, luteinized cells had mild staining, there was no difference in other cell groups. Only theca externa cells of the developing follicles were stained in insulin plus hCG group, luteinized cells again had mild staining. CONCLUSIONS: Besides damaging the rat ovarian structure, insulin reduced staining intensity of leptin in luteinized cells. Insulin may stimulate ovarian steroid synthesis not only through its own receptors, but also by acting on the leptin expression of these cells.

Animals↗

PubMed2002

The effect of tibolone on endometrial IGF-1 and IGFBP-1 levels in ovariectomized rats.

OBJECTIVE: The goal of this study was to search the effects of two different doses of tibolone on endometrial IGF-1 and IGFBP-1 levels in ovariectomized rats. METHODS: Eighteen adult, female, 80-90-days-old, Wistar rats with an average weight of 250 g underwent bilateral ovariectomy under general anesthesia. After waiting for 4 weeks, they were randomized into three groups to receive either oral tibolone in two different doses or placebo. The treatment was continued for 5 weeks, and then the rats were sacrificed and the endometria were analyzed. RESULTS: Low columnar epithelium of the endometrial surface, longer epithelium and stratified squamous epithelium were seen in the control, low-dose and high-dose groups, respectively. The staining intensity of IGF-1 was mild in control, and moderate in both treatment groups, the difference between control the treatment groups was significant (P=0.015 for group L, and P=0.03 for group H). The staining intensity of IGFBP-1 was moderate in control, and strong in groups L and H. Again the difference was significant between control and both treatment groups (P=0.039 for grup L, and P=0.03 for group H). No significant difference was noted between each treatment group for both IGF-1 and IGFBP-1. CONCLUSION: Tibolone caused histological changes in endometrium and stimulated IGF-1 and IGFBP-1 staining. Both low and high dose treatments led to moderate and strong staining intensities for IGF-1 and IGFBP-1, respectively. The strong staining intensity of IGFBP-1 is likely due to the progestagenic effect of tibolone.

Animals↗

PubMed2002

Comparative morphological differences between umbilical cords from chronic hypertensive and preeclamptic pregnancies.

To compare morphological changes in the umbilical cords from chronic hypertensive and preeclamptic patients having normal or pathological umbilical artery Doppler ultrasonographic results. Umbilical cords from 34 normotensive, 31 chronic hypertensive and 70 preeclamptic women with normal and abnormal Doppler flow velocity waveforms (FVW) at 35-40 gestational weeks were studied. Morphological changes in the umbilical cords were examined on formalin-fixed, paraffin-embedded sections. The total umbilical cord area, total vessel area, and wall thickness of umbilical vessels were measured in systematic random samples using unbiased stereology methods. An ANOVA test was used for statistical analysis. In the chronic hypertensive and preeclamptic groups with normal Doppler FVW, the thickness of the umbilical cord vessels remained nearly constant, whereas both the total area and the lumen area were reduced. These changes correlate with the histopathological findings, suggesting a mainly vasoconstrictive effect. By contrast, analysis of the preeclamptic group with pathologic Doppler FVW showed a comparable reduction of all parameters of the umbilical cord. Histopathological findings were related to smaller, contracted smooth muscle cells of the vessel wall, which is suggestive of a predominant hypoplastic mechanism. As a result of reduced uteroplacental perfusion, fetal hypoxia and intrauterine growth retardation become unavoidable in preeclampsia. The histopathological changes in the umbilical cord between the chronic hypertensive and preeclamptic patients depend on the Doppler results. In conclusion, the umbilical artery Doppler FVW indices provide good values for predicting intrauterine growth retardation in preeclamptic patients.

Adult↗