Comparison of the effects of Contractubex® gel in an experimental model of scar formation in rats: an immunohistochemical and ultrastructural study.

BACKGROUND: Contractubex® gel, a commercial treatment for scars, consists of a mixture of onion extract (cepea extract), heparin sodium, and allantoin. It exerts a softening and smoothing effect on indurated, hypertrophic, painful, and cosmetically-disfiguring scar tissue. AIM: To compare and discuss the immunohistochemical and ultrastructural effects of treatment of an experimental scar in a rat model with Contractubex gel. METHODS: Thirty-two Sprague-Dawley rats were divided into four groups. Skin biopsies were taken to develop full thickness wounds. After 10 days, Contractubex gel, heparin, and allantoin were topically applied daily to groups 2, 3, and 4, respectively. Group 1 was the control group. On the 30th day, scar tissues were excised to investigate the immunohistochemical and ultrastructural effects of these agents. For this purpose we used TGF-beta, laminin, and fibronectin primary antibodies. RESULTS: Increased immunoreactivities of laminin, fibronectin, and TGF-beta in control group, moderate immunoreactivities in heparin and allantoin groups, and mild immunoreactivities in the Contractubex gel group were observed. In semi-thin sections, Group 2 showed the thinnest epidermis of the four groups. In electron micrographs of Group 2, completely keratinized and normally appearing cells could be seen. CONCLUSIONS: Immunohistochemical and ultrastructural observations demonstrated that the Contractubex gel significantly improved the quality of wound healing and reduction of scar formation. Also, it was a more appropriate treatment choice than heparin monotherapy and allantoin monotherapy in keloidal and hypertrophic scars.

Effect of ovarian stimulation with human menopausal gonadotropin and recombinant follicle stimulating hormone on the expression of integrins alpha3, beta1 in the rat endometrium during the implantation period.

OBJECTIVE: To investigate the effect of exogenous ovarian stimulation with human menopausal gonadotropin (hMG) and recombinant follicle stimulating hormone (rFSH) on the expression of integrins alpha(3), beta(1) in the rat endometrium during implantation. STUDY DESIGN: Following three successive normal estrous cycles the animals were divided into five groups: Group I (n=10, control group) received no medication; Group II (n=10) received 10 units of hMG; Group III (n=10) received 20 units of hMG; Group IV (n=10) received 10 units of rFSH; Group V (n=10) received 20 units of rFSH at midday of middiestrous. The rats were then mated with fertile males. The animals were sacrificed on the day of implantation. The uterine horns were placed in fixative and paraffin blocks of the tissue were cut in 5 microm sections. The tissues were stained with primary antibodies; monoclonal anti-integrin alpha(3) and monoclonal anti-integrin beta(1) using immunohistochemical methods. The staining intensities of alpha(3) and beta(1) integrins were calculated separately for epithelium and stroma in each group. RESULTS: Staining intensities of alpha(3) and beta(1) integrins in both the epithelium and the stroma were significantly lower in the treatment groups than the control group (p<0.05). CONCLUSION: Ovarian stimulation by low and high doses of HMG and rFSH may have an effect on endometrial receptivity, possibly via a decrease in expression of integrins in the endometrium during the implantation period.

The immunohistochemical evaluation of VEGF in placenta biopsies of pregnancies complicated by preeclampsia.

OBJECTIVE: The study was designed to determine the protein levels of vascular endothelial growth factor (VEGF) in the placenta biopsies of patients with preeclampsia and compare with normal controls. DESIGN: Prospective cohort study. METHODS: The placental biopsies were obtained from ten patients with preeclampsia and ten patients of control group at the time of delivery. Avidin-biotin-peroxidase immunohistochemistry was then performed to identify levels of VEGF protein within the tissue and a semi-quantitative method was devised to score the amount of staining present in the sample. Two histopathologists who were blinded to the groups were asked to score each sample for the intensity of staining and the number of cells stained in a randomly selected per high-power fields of each sample. The resulting "H-score" was computed as a product of intensity and percent of cells stained. RESULTS: The VEGF expression was significantly higher in placenta biopsies of preeclamptic patients compared to that of controls (271.2 +/- 22.65 vs. 201.9 +/- 12.33, P = 0.000). CONCLUSION: Immunostaining of VEGF is significantly higher in placenta biopsies of patients with preeclampsia.

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.

Effect of thermal energy produced by drilling on the facial nerve: histopathologic evaluation in guinea pigs.

The effect of thermal energy due to drilling around the facial nerve canal on the facial nerve was histopathologically evaluated in four guinea pigs. The bony canal of the facial nerve was drilled using a 3 mm diamond burr for one minute. The temperature changes on the facial nerve canal were noted before and after dissection. The temporal bones of the animals were histopathologically examined under light microscopy using haematoxylin & eosin (H&E) and solochrome cyanine staining for myelin, and immunohistochemical staining for neuronal nitric oxide synthase (nNOS). Compared to the control group, it was observed with H&E staining that there was oedema among the axonal fibres and with solochrome cyanine staining that the thickness of the myelin fibres was decreased, and that the severity and extent of nNOS activity was decreased in the axonal fibres. It was concluded that a temperature increase on the facial canal may potentially lead to inflammation of the nerve, and may also cause deterioration of nerve conduction to some extent.

Pre-ischemic administration of nitric oxide synthase inhibitors reduced germ cell apoptosis after spermatic vessel ligation in the rat testis.

INTRODUCTION: The Fowler-Stephens maneuver, a mode of spermatic vessel ligation, is a method of choice in the management of high testes. The aim of the present study is to investigate the effects of pre-ischemic administration of N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide (NO) synthase (NOS) inhibitor, in preventing testicular ischemic damage and germ cell-specific apoptosis in rats. MATERIALS AND METHODS: 30 min before ligation of the spermatic vessels, L-NAME was administered intraperitoneally to a group of rats and saline was given to another group of rats (controls). Biochemical assessments of NO and germ cell-specific apoptosis were performed. RESULTS: Testicular NO levels in the L-NAME group showed significant decreases in the ipsilateral (p = 0.004) and contralateral (p = 0.015) testes in relation to those of the control group. The apoptotic indices were found in 2.3% of the L-NAME group and 3.1% of the control group. CONCLUSION: Pre-ischemic administrations of the NOS inhibitor, L-NAME, effectively decreased NO production and to some degree caused a reduction in germ cell apoptosis in the rat testes after spermatic vessel ligation. Further studies are mandatory to confirm our preliminary results and to address the potential introduction of NOS inhibitors into clinical practice.

The effect of spermatic vessel ligation on testicular nitric oxide levels and germ cell-specific apoptosis in rat testis.

Management of high testis may vary but the most popular method in surgical treatment is the Fowler-Stephens maneuver. The aim of the present study was to investigate the effects of spermatic vessel ligation on testicular nitric oxide (NO) levels, expression of inducible nitric oxide synthase (iNOS), and endothelial nitric oxide synthase (eNOS) and germ cell-specific apoptosis in both ipsilateral and contralateral testes in rats. Twenty-eight animals were randomly allocated into four groups (n=7 each). The spermatic vessels were ligated as a simulation of the Fowler-Stephens maneuver. The groups of animals were sacrificed at 2 h (group 1), 4 h (group 2) and 24 h (group 3) after ligation, respectively. Sham-operated animals served as controls (group 4). Biochemical assessment of testicular NO levels was performed by the Griess method. iNOS and eNOS expression and apoptosis were studied in ipsilateral and contralateral testes. Testicular NO levels at 24 h after the simulated Fowler-Stephens maneuver were found to be significantly increased in both ipsilateral and contralateral testes when compared with the sham-operated group. eNOS expression was clearly increased in ipsilateral testes, whereas moderate expression was detected in the contralateral seminiferous tubules at 24 h after ligation. Mild focal iNOS immunostaining was also observed in seminiferous tubules of the ipsilateral testis at 24 h after the simulated Fowler-Stephens maneuver. Apoptosis was dramatically increased in ipsilateral testes; however, it was only detected in single cells in the contralateral side at 24 h after ligation. In conclusion, the simulated Fowler-Stephens maneuver induces testicular nitric oxide synthesis and germ cell-specific apoptosis in the ipsilateral testis. These results suggest that high levels of NO induce apoptosis and may impair spermatogenesis thus explaining the unsuccessful outcome of the Fowler-Stephens maneuver.

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.

Increased expression of angiogenic markers in patients with seasonal allergic rhinitis.

BACKGROUND: Increased vascularity due to neo-angiogenesis is an essential part of airway remodelling. Vascular endothelial growth factor (VEGF), CD34 and von Willebrand's factor (FvW) are known angiogenic markers. Angiogenesis and airway remodelling has been documented in asthma but not in allergic rhinitis. OBJECTIVE: We aimed to investigate the presence of increased angiogenesis and its relation to angiogenic molecules, namely VEGF, CD34 and FvW, in endothelial cells of nasal mucosa in patients with seasonal allergic rhinitis (SAR), using three different immunohistochemical analysis methods, namely HSCORE, microvessel density (MVD) and vascular surface density (VSD). The findings in allergic rhinitis were compared with the findings in nasal septal deviation (NSD), which is not associated with increased angiogenesis. METHODS: Twenty patients with symptomatic SAR, who were not under treatment, were enrolled in the study. Ten patients with NSD, who needed surgical therapy, served as the control group. Demographic characteristics did not differ between the two groups. Inferior turbinate biopsy was obtained from SAR patients and control patients, under local anaesthesia and during surgery respectively. All biopsies were evaluated for angiogenesis on the basis of VEGF, CD34 and FvW by two blinded histologists using three immunohistochemical analysis methods (HSCORE, MVD and VSD).Results. HSCORE, estimated on the basis of each staining technique, showed statistically significant differences among the two groups (p=0.002; p=0.045; p=0.016, respectively). Anti-CD34 and anti-VEGF showed higher MVD values in SAR when compared to the controls (p=0.038; p=0,009, respectively). No statistically significant difference was found in Anti-FvW-based MVD between SAR patients and controls (p=0.071). The measurements of VSD for FvW and VEGF from nasal biopsy specimens displayed a statistically significant difference between the two groups (p=0.004; p=0.0001, respectively). However, measurement of VSD for CD-34 was not significantly different between the groups (p=0.086). On the other hand, morphometric data obtained by all three methods did not correlated. CONCLUSION: There are a few studies that have investigated the essential role of angiogenesis in the pathogenesis of allergic rhinitis. We conclude that, increased angiogenesis may be as prominent in patients with allergic rhinitis as in patients with non-allergic nasal pathologies and may play an important role in the remodelling of nasal mucosa of subjects with SAR.

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.