Autogenous Tooth Bone Graft and Simvastatin Combination Effect on Bone Healing.

OBJECTIVE: Autogenous tooth bone grafts (ATGM) are materials prepared from extracted teeth and have been used for bone augmentation. These graft materials are known to have similar structures and components to bone grafts. In this sense, this study aimed to evaluate all the tooth layers mixed with simvastatin without any demineralization process effect on bone formation. METHODS: In 60 Wistar albino rats, a standardized 6.0 m-diameter critical size bone defect was created in their calvarium. The study consists of 1 control and 4 experimental groups. In the control group (12 rats), the defects were left empty. The defects were grafted only with ATGM in Group 1, with ATGM mixed with simvastatin in Group 2, autogenous bone graft mixed with simvastatin in Group 3, and with xenogenic bone graft mixed with simvastatin in Group 4. The animals were sacrificed at the 7th and 28th days after operation. RESULTS: PCR, micro CT and histological results show that bone formation was enhanced in the experimental groups in comparison to the control group. Group 1 and Group 2 had similar bone formation rate when compared to Group 3 and Group 4 at the 28th day after operation. CONCLUSION: This study concludes that mineralized teeth may be used for defect reconstruction without any demineralization process. Autogenous mineralized tooth bone graft should be mixed with simvastatin for bone regeneration like other grafts.

The Effect of Vascular Graft and Human Umbilical Cord Blood-Derived CD34+ Stem Cell on Peripheral Nerve Healing.

AIM: There are many trials concerning peripheral nerve damage causes and treatment options. Unfortunately, nerve damage is still a major problem regarding health, social and economic issues. On this study, we used vascular graft and human cord blood derived stem cells to find an alternative treatment solution to this problem. MATERIAL AND METHODS: We used 21 female Wistar rats on our study. They were anesthetized with ketamine and we studied right hind limbs. On Group 1, we did a full layer cut on the right sciatic nerve. On Group 2, we did a full layer cut on the right sciatic nerve, and we covered synthetic vascular graft on cut area. On Group 3, we did a full layer cut on right sciatic nerve, and we covered the area with stem cell applied vascular graft. RESULTS: At the end of postoperative 8. weeks, we performed EMG on the rats. When we compared healthy and degenerated areas as a result of EMG, we found significant amplitude differences between the groups on healthy areas whereas there was no significant difference on degenerated areas between the groups. Then we re-opened the operated area again to reveal the sciatic nerve cut area, and we performed electron microscope evaluation. On the stem cell group, we observed that both the axon and the myelin sheet prevented degeneration. CONCLUSION: This study is a first on using synthetic vascular graft and cord blood derived CD34+ cells in peripheral nerve degeneration. On the tissues that were examined with electron microscope, we observed that CD34+ cells prevented both axonal and myelin sheath degeneration. Nerve tissue showed similar results to the control group, and the damage was minimal.

Tissue reaction to urogynecologic meshes: effect of steroid soaking in two different mesh models.

INTRODUCTION AND HYPOTHESIS: Steroid soaking may decrease mesh-triggered inflammatory reaction in tissue. We aimed to investigate the tissue reaction to a steroid-soaked mesh material and an unsoaked mesh material in the rat model. METHODS: Neutral and steroid-soaked type I macroporous polypropylene (PP) monofilament and polyvinylidene fluoride (PVF) mesh materials were implanted on the rectus abdominis muscle of 20 mature Wistar albino rats. Animals were divided into four groups: PP mesh with steroid (PP-S), PP mesh without steroid, PVF mesh with steroid (PVF-S), and PVF mesh without steroid. The rats were killed after 12 weeks, and histologic, immunohistochemical and electron microscopic examinations were performed. For immunohistochemical analysis, polyclonal rabbit anti-mouse CD3, rabbit anti-mouse CD68, rabbit anti-mouse CD15, and rabbit anti-mouse CD34 antibodies were used for the detection of lymphocytes, macrophages, polymorphonuclear leukocyte foreign body giant cells, and fibromyocyte stem cells, respectively. Samples were stained with hematoxylin and eosin for the histologic evaluation of inflammation and with Masson's trichrome stain for the evaluation of collagen deposition. Pore size and mesh ultrastructure were evaluated by electron microscopy. RESULTS: Expression of CD3 was lower in the PVF, PVF-S and PP-S groups, and expression of CD34 was higher in the PVF-S and PP-S groups than in the PP groups (p < 0.05). Collagen deposition was lower in the PVF, PVF-S and PP-S groups (p < 0.05). Histologically, the intensity of inflammation was lower in the PVF-S and PP-S groups than in the PP mesh group (p < 0.05). There were no significant differences among the groups in terms of pore size and mesh ultrastructure on electron microscopic examination (p > 0.05). CONCLUSIONS: PVF mesh induces less inflammation than PP mesh, and in both mesh types steroid soaking further decreases inflammation without changing the pore size.

Preventive effects of vitamin E against oxidative damage in aged diabetic rat bladders.

OBJECTIVES: To examine the effects of aging and/or diabetes mellitus on oxidative stress and the protective effect of vitamin E in the bladder. It was proposed that the balance between oxidant and antioxidant species is important regarding the aging process and prevention of diabetic complications. METHODS: Young and aged rats were randomly allotted into six experimental groups: aged control, aged diabetic, aged diabetic and vitamin E-treated, young control, young diabetic, young diabetic and vitamin E-treated. Diabetes was induced by streptozotocin. Vitamin E was administered to the treated groups. Malondialdehyde and reduced glutathione levels were measured in all rat bladders, and histological changes were examined by electron microscopy. RESULTS: We found increased malondialdehyde and decreased glutathione levels in the young and aged diabetic groups compared with the nondiabetic control groups. Elevated malondialdehyde and reduced glutathione levels were observed in the aged compared with the young control groups. There were no significant differences in the malondialdehyde and glutathione levels between young and aged diabetic vitamin E-treated groups compared with the related control groups. Degeneration was greatest in the aged diabetic group. The protective effects of vitamin E were seen in young and aged diabetic groups, especially in the young diabetic group. CONCLUSIONS: Our results suggest that vitamin E supplementation prevents free radical damage in bladders of young and aged diabetic rats.

Effects of retinoic acid and zinc on the treatment of caustic esophageal burns.

PURPOSE: An experimental study was carried out to investigate the efficacy of an anti-inflammatory and antiproliferative agent all-trans retinoic acid (ATRA) and an antioxidant agent zinc sulphate (ZnSO(4)) in the prevention of stricture after caustic esophageal burn in rats. METHODS: Esophageal burn was induced using 50% NaOH. Rats were divided into four groups as follows: group A (sham; n = 8), group B (control; n = 8), group C (treated with ATRA; n = 8) and group D (treated with ZnSO(4); n = 8). All rats were killed on the 28th day and esophageal tissues were evaluated for histopathologic damage score, hydroxyproline (HP) content and TGF-beta1 expression. RESULTS: Significant difference was detected in terms of histopathologic damage score between groups B and C (p = 0.002). Although mean HP levels of groups C and D were lower than group B, statistical comparison was not significant. TGF-beta1 expression in group C was significantly lower than group B. CONCLUSION: Zinc has not been found effective in the prevention of stricture formation. The results indicate that ATRA has a preventive effect in the development of fibrosis in an experimental model of caustic esophageal burns in rats.

Stem cell support of oogenesis in the human.

The possibility that women produce new oocytes post-natally as part of the normal physiological function of the ovary is currently under investigation. Post-natal production of oocyte-like cells has been detected under experimental conditions in the mouse. Although these cells have many characteristics of oocytes, their potential to mature to fertilization-competence was unproven. Zou et al. (Production of offspring from a germline stem cell line derived from neonatal ovaries. Nat Cell Biol 2009;11:631-636) made use of a striking cell isolation and culture strategy to establish cultures of proliferative germ cells from both newborn and adult ovaries. Their cells, referred to as female germline stem cells (FGSCs), proliferate long-term in culture and accept and maintain expression of a transgenic marker, green fluorescent protein. When delivered to the ovaries of conditioned mice, transgene-bearing FGSC engrafted, were enclosed within follicles, and when host females were mated, transgenic offspring were produced. That proliferative female germ cells capable of giving rise to offspring were detected in adult ovaries poses the question of whether they have a physiological role. Here, we discuss Zou et al.'s data in terms of our current understanding of mouse ovarian physiology, and how this may relate to human reproductive biology and the treatment of ovarian dysfunction.

Regulation of the vitamin D receptor and cornifin beta expression in vaginal epithelium of the rats through vitamin D3.

The aim of the present study was to determine the respective role of 1,25-dihydroxyvitamin D3 on vaginal epithelium and 1,25-dihydroxyvitamin D3 receptor expression in ovariectomized rats and vitamin D3 treated rats. Bilateral ovariectomies were performed in 20 mature, non-pregnant Wistar female rats. All the animals were divided into 2 groups consisting of 10 rats each. Group I served as control. In group II, animals were injected intramuscularly with vitamin D3 (50, 00 IU/kg). Two weeks after the injections, vaginas of animals in group I and group II were removed removed and processed for immunohistochemistry. Epithelial differentiation, 1,25-dihydroxyvitamin D3 receptor and cornifin beta expression were investigated in vaginal epithelium of control group (ovariectomized) and vitamin D3 treated rats. Vaginal epithelial cells from vitamin D3 treated animals changed into highly- stratified keratinizing layers. 1,25-dihydroxyvitamin D3 receptor and cornifin beta as a marker of squamous differentiation were present in ovariectomized rats treated with 1,25-dihydroxyvitamin D3. In contrast, cornifin beta and 1,25-dihydroxyvitamin D3 receptor were absent in all layers of vaginal epithelium in control group. We demonstrated for the first time that 1,25-dihydroxyvitamin D3 induced proliferation of vaginal epithelium consistent with the cornifin beta expression and 1,25-dihydroxyvitamin D3 up-regulated 1,25-dihydroxyvitamin D3 receptor expression in vaginal epithelium.

Transmission electron microscopy study of the effects of cadmium and copper on fetal rat liver tissue.

During the entire period of their pregnancies, three groups of adult pregnant Wistar albino rats were provided with tap water (control; group I) or with tap water containing 10 mg/kg CdCl2 (group II) or 10 mg/kg CdCl2 plus 10 mg/kg CuSO4 (group III). At term, the animals were sacrificed and the fetal livers were removed and examined under electron microscopy. The liver tissue of the fetuses in maternal groups II and III showed degenerative changes to their hepatocytes. In group II, the smooth endoplasmic reticulum tubules showed dilatation, and the mitochondria showed a dense matrix. In group III, some mitochondrial degeneration was also seen, with a diluted matrix and mitochondrial dilatation. There were also more heterochromatic nuclei and an increased number of ribosomes. None of these histopathological changes were present in the fetal liver samples from the maternal group I control animals.

Amelioration of aluminium-induced liver damage by vitamin E.

OBJECTIVE: To investigate the effects of aluminium sulphate on the microscopic morphology of the liver and on vitamin E amelioration of aluminium-induced liver damage. METHODS: Rats were injected intraperitoneally with aluminium sulphate alone or aluminium sulphate together with vitamin E, with saline injected rats used as the control group. The study took place in Pamukkale University Faculty of Medicine in 2005. RESULTS: The rats exposed to aluminium showed morphological changes in addition to previously reported biochemical changes in the liver. The anti-oxidant vitamin E significantly diminished the liver damage seen due to aluminium. CONCLUSION: There is an apparent protective effect of vitamin E on parenteral aluminium exposure.

The effect of in ovo ethanol exposure on retina and optic nerve in a chick embryo model system.

Ocular anomalies seen in children with fetal alcohol syndrome (FAS) suggest that ocular structures are sensitive to alcohol exposure during their development. This study was designed to investigate the effect of in ovo ethanol (EtOH) exposure on retinal development and myelinization of optic nerve fibers at an ultra structural level in a chick embryo model system. Prior to incubation, fertilized chicken eggs were injected once with 100 microl of either 0.9% NaCl (vehicle control), or EtOH solutions at different doses (10, 30, or 50%, v:v in 0.9% NaCl) into their air sacs and incubated at 37.5 degrees C and saturation humidity. On day 20 embryos were analyzed in terms of their viability and growth and the optic cups including the optic nerves were dissected out. Specimens were processed for electron microscopy (EM). Results showed that, EtOH significantly decreased the viability of chick embryos (P < 0.045), and caused significant prenatal growth retardation (P < 0.004) in a dose-dependant manner. Light microscopy of semi thin sections revealed that prenatal exposure to EtOH resulted in both retinal degeneration and optic nerve hypoplasia (P < 0.001) in a dose-dependant manner. EM revealed that a dose-dependant decrease in the number of myelinated nerve fibers was profound in groups exposed to EtOH (P < 0.001). Furthermore, the myelin coats observed were thinner than those seen in control embryos. In groups exposed to EtOH myelin sheets were unorganized and contained vacuolar structures in between them. The tissue in between the cells and optic nerve fibers, on the other hand, lost its intact appearance with vacuolar and vesicular structures in between them. In addition, the optic nerve fibers contained granular accumulations in EtOH exposed groups. A dose dependent degeneration was also observed in retinas of EtOH exposed groups. The effect of EtOH was profound in pigment epithelium (PE), inner plexiform layer (IPL), and ganglion cell layer (GC). Mitochondrial deficiencies, and alterations in melanin granule number and distribution dominated the defects seen in PE. On the other hand, EM findings of all the affected layers were suggestive of induced cell death in EtOH exposed groups. Thus, this study suggests retinal development with the emphasis on melanin pigmentation in PE and optic nerve myelinization as potential targets of prenatal EtOH exposure and discusses potential mechanisms of EtOH action on these tissues.

The preventive effect of vitamin D3 on radiation-induced hair toxicity in a rat model.

Our aim is to investigate the protective effect of vitamin D3 especially from radiation-induced hair toxicity. A model of skin radiation injury was developed and a single fraction of 20 Gy Gamma irradiation was applied to the right dorsal skin of fourteen rats. All animals were randomly divided into 2 groups: Group I: irradiation alone (n = 7) and Group II: irradiation and 0.2 microg vitamin D3 given IM (n = 7). Fifty days after post-irradiation rats were sacrificed. The outcomes were evaluated on the basis of histopathological findings and immunohistochemical staining for Vitamin D receptor (VDR) in skin and hair follicles. The number of hair follicles in the radiation field for the group of animals irradiated without pretreatment was significantly lower than outside of the irradiated area (p = 0.016) as it is expected. Contrarily the number of hair follicles did not show significant difference in the pretreated group between the irradiated field and outside of the fields (p = 0,14). Skin of the vitamin D3 pretreated group demonstrated stronger immunoreactivity for VDR compared to irradiation alone group. These results indicate that administration of vitamin D3 may protect hair follicles from radiation toxicity. Further clinical trials should be conducted to prove the preventive effect of vitamin D3 as well as dosing and timing of the agent on radiation-induced alopecia.

Immunohistochemical detection of 1,25-dihydroxyvitamin D receptor in rat vaginal epithelium.

OBJECTIVE: To determine the distribution of 1,25-dihydroxyvitamin D receptor (VDR) in rat vaginal epithelium during the estrus cycle and in ovariectomized rats. DESIGN: Animal study performed in two groups of rats. The expression of VDR was examined in the first group during the estrous cycle and in the second group after ovariectomy. SETTING: University animal laboratory. ANIMAL(S): Balb/c female rats. INTERVENTION(S): Vaginas were removed and processed for immunohistochemical analysis. MAIN OUTCOME MEASURE(S): We recorded the localization, distribution, and expression of VDR in vaginal epithelium during the rat estrus cycle and in ovariectomized rats. RESULT(S): In cyclic rats, VDR was detected in basal and suprabasal cells during all of the cycle periods. In apical cells, VDR was positive in diestrus and estrus but negative in proestrous. In ovariectomized rats, VDR was not detected in any layers of vaginal epithelium. CONCLUSION(S): In vaginal epithelium, the presence of VDR was shown by using immunohistochemical techniques. During the estrous cycle, VDR has an important role in the proliferation and differentiation of vaginal squamous epithelium that is similar to the effects of estrogen.

Transmission electron microscopy study of the effects of zinc overdose on mouse liver tissue.

Thirty adult male mice were divided into three groups. The animals in group I were used as controls and drank only water during the entire period of experimentation. Group II animals drank water containing 1.5 g/100 mL zinc as ZnSO4, and group III animals received 2.5 g/100 mL zinc. After 3 wk supplementation with high doses of zinc, the animals were killed and the livers were removed and examined by electron microscopic techniques. After the supplementation period, the animals in groups II and II showed various degrees of degenerative changes in the hepatocytes, such as increased size and the presence of spaces and an abundance of lipid globules in the cytoplasm. The mitochondria showed a crystalline appearance, a diluted matrix, and dense aggregations. Some smooth endoplasmic reticulum tubules showed dilation and were filled with a dense substance. None of these changes were present in the group I control animals.

Effect of overdose zinc on mouse testis and its relation with sperm count and motility.

The purpose of this study was to investigate the effects of excessive zinc intake on the testes and on sperm count and motility in mice. Thirty Balb c mice were divided randomly into 3 groups of 10 animals in each. Group I acted as controls; group II was supplied with drinking water containing 1.5 g/100 mL Zn, and group III was supplied with drinking water containing 2.5 g/100 mL Zn. The animals were sacrificed after 3 wk supplementation and the epididymis and testis were quickly excised. A negative correlation between Zn dose and sperm count and motility was found. The sperm count in group III was significantly lower than in groups II and I (p<0.05). The sperm motility in group III was significantly lower than in the controls (p<0.05). Degenerative changes, including spermatic arrest, degeneration of seminiferous tubules, and fibrosis in interstitial tissue, were observed in group III animals. These results show that high doses of zinc significantly alter sperm motility.