Effects of restraint stress and high-fat diet on osseointegration of titanium implants: an experimental study

Abstract This study aimed to investigate the effects of chronic restraint stress (RS) and a high-fat diet (HFD) on the osseointegration of titanium implants in a rat model. After the surgical insertion of titanium implants into the metaphysis of the tibial bone, the rats were randomly divided into four equal groups (n = 8 each): control (CNT), restraint stress (RS), high-fat diet (HFD), and restraint stress plus high fat diet (RS-HFD). CNT: Rats received no further treatment during the 92-day experimental period. RS: Stress was applied to the rats beginning from two days after the implant surgery for one hour per day for the first 30 days, two hours per day for the next 30 days, and three hours per day for the last 30 days. HFD: Rats were fed a HFD for the following 90 days starting two days after surgery. RS-HFD: Rats were fed a HFD and RS was applied to rats for the following 90 days, starting two days after surgery. At the end of the experimental period, the rats were euthanized, and the implants and surrounding bone tissues were removed for histological analysis. Statistical analysis was performed by one way ANOVA and Bonferrroni tests. There were no significant differences in the bone-implant connection levels between the groups (p > 0.05), but in the HFD and RS-HFD groups, the bone filling ratios were found to be lower compared with the controls (p < 0.05) The data analyzed in this study suggest that an HFD with or without chronic RS adversely affected bone tissue in the rats during the 90-day osseointegration period.

Effects of restraint stress and high-fat diet on osseointegration of titanium implants: an experimental study

Abstract This study aimed to investigate the effects of chronic restraint stress (RS) and a high-fat diet (HFD) on the osseointegration of titanium implants in a rat model. After the surgical insertion of titanium implants into the metaphysis of the tibial bone, the rats were randomly divided into four equal groups (n = 8 each): control (CNT), restraint stress (RS), high-fat diet (HFD), and restraint stress plus high fat diet (RS-HFD). CNT: Rats received no further treatment during the 92-day experimental period. RS: Stress was applied to the rats beginning from two days after the implant surgery for one hour per day for the first 30 days, two hours per day for the next 30 days, and three hours per day for the last 30 days. HFD: Rats were fed a HFD for the following 90 days starting two days after surgery. RS-HFD: Rats were fed a HFD and RS was applied to rats for the following 90 days, starting two days after surgery. At the end of the experimental period, the rats were euthanized, and the implants and surrounding bone tissues were removed for histological analysis. Statistical analysis was performed by one way ANOVA and Bonferrroni tests. There were no significant differences in the bone-implant connection levels between the groups (p > 0.05), but in the HFD and RS-HFD groups, the bone filling ratios were found to be lower compared with the controls (p < 0.05) The data analyzed in this study suggest that an HFD with or without chronic RS adversely affected bone tissue in the rats during the 90-day osseointegration period.

Immunhistochemical analysis of Nuclear Factor Kappa Beta expression in etiopathogenesis of ovarian tumors

Abstract Purpose: To investigate the place of the transcription factor nuclear kappa B (NF-kB), which is a marker of chronic inflammation, in the etiology of the ovarian carcinoma. Methods: NFkB analysis with the immunohistochemical method has been performed. To evaluate immunohistochemical NF-kB expression in the ovarian tissue, the H-score method. H-score = ∑ Pi (i+1), where ''Pi'' is the percentage of stained cells in each intensity category (0-100%) and ''i'' is the intensity indicating weak (i=1), moderate (i=2) or strong staining (i=3). Results: It has been seen that, the mean H score is statistically significantly higher in the patient group with serous and musinous adenocarcinoma diagnosis than the two other patient groups (p<0.005). Conclusions: Factor nuclear kappa B is an important mediator that acts in the chronic inflammation. The highest expression rates are determined by the immunohistochemical method in the ovarian cancer group.

Investigation of the effect of gestational diabetes on fetal cardiac tissue in streptozotocin induced in rats

Abstract Purpose: To investigate the cause of congenital anomalies resulted from gestational diabetes on fetal cardiac tissue in experimental animal study model. Methods: Totally 12 female Wistar albino rats were divided into two groups, each consisting of 6 rats. Streptozotocin (60 mg/kg) was administered intraperitoneally to the study group by dissolving in citrate solution. The rats with a blood glucose level of 200 mg/dL and above were considered to be diabetic rats. Total antioxidant status (TAS), total oxidative stress (TOS) and oxidative stress index (OSI) values were calculated in the cardiac tissues and maternal serum samples of the fetuses delivered by cesarean section after the mating process. The cardiac tissues were also subjected to histopathological examination. Results: TOS and OSI values in fetal cardiac tissues of the diabetic rats were found to be significantly higher than that of the control group (p=0.026 and p=0.005). Histopathological examination revealed that the mitotic index was lower and the cell organization was found to be damaged in the fetuses of the study group rats. Conclusion: Increased levels of free oxygen radicals considered to be due to hyperglycemia may cause congenital anomalies, especially during organogenesis period, by disrupting cell homeostasis and adversely affecting mitosis.

A comparison of different bone graft materials in peri-implant guided bone regeneration

Abstract The aim of this study was to compare the effects of hydroxyapatite (HA), deproteinized bovine bone (DPB), human-derived allogenic bone (HALG), and calcium sulfate (CAP) graft biomaterials used with titanium barriers for bone augmentation to treat peri-implant defects in rat calvarium treated by guided bone regeneration (GBR). Thirty-two female Sprague-Dawley rats were divided into four groups: DPB, HALG, HA, and CAP. One titanium barrier was fixed to each rat's calvarium after the titanium implants had been fixed. In total, 32 titanium implants and barriers were used. Ninety days after the surgical procedure, all the barriers were removed. After decalcification of bone tissue, the titanium implants were removed gently, and new bone regeneration in the peri-implant area was analyzed histologically. Immunohistochemical staining of vascular endothelial growth factor (VEGF) was also performed. There were no statistically significant between-group differences in new bone regeneration or VEGF expression after 3 months. According to the results of the histological and immunohistochemical analyses, none of the grafts used in this study showed superiority with respect to new bone formation.

Does alfa lipoic acid prevent liver from methotrexate induced oxidative injury in rats?

PURPOSE: To determine the antioxidant and anti-inflammatory effects of alfa lipoic acid (ALA) on the liver injury induced by methotrexate (MTX) in rats. METHODS: Thirty two rats were randomly assigned into four equal groups; control, ALA, MTX and MTX with ALA groups. Liver injury was performed with a single dose of MTX (20 mg/kg) to groups 3 and 4. The ALA was administered intraperitonealy for five days in groups 2 and 4. The other rats received saline injection. At the sixth day the rats decapitated, blood and liver tissue samples were removed for TNF-α, IL-1β, malondialdehyde, glutathione, myeloperoxidase and sodium potassium-adenosine triphosphatase levels measurement and histological examination. RESULTS: MTX administration caused a significant decrease in tissue GSH, and tissue Na+, K+ ATPase activity and which was accompanied with significant increases in tissue MDA and MPO activity. Moreover the pro-inflammatory cytokines (TNF-α, IL- β) were significantly increased in the MTX group. On the other hand, ALA treatment reversed all these biochemical indices as well as histopathological alterations induced by MTX. CONCLUSION: Alfa lipoic acid ameliorates methotrexate induced oxidative damage of liver in rats with its anti-inflammatory and antioxidant effects. .

Exogenous ATP administration prevents ischemia/reperfusion-induced oxidative stress and tissue injury by modulation of hypoxanthine metabolic pathway in rat ovary / Administração exógena de ATP impede isquemia/induzidas por reperfusão de estresse oxidativo de tecidos e lesões pela modulação da hipoxantina via metabólica em ovários de ratos

In this study, xanthine oxidase (XO), malondialdehyde (MDA), myeloperoxidase (MPO) and glutathione (GSH) levels in the ovarian tissues of rats during the development of ischemia and postischemia-induced reperfusion were investigated, and the effect of ATP on ischemia-reperfusion (I/R) damage was biochemically and histopathologically examined. The results of the biochemical analyses demonstrated that ATP significantly reduced the level of XO and MDA and increased the amount of GSH in both ischemia and I/R-applied ovarian tissue at the doses administered. Furthermore, ATP significantly suppressed the increase in MPO activity that occurred following the application of post ischemia reperfusion in the ovarian tissue. The biochemical results obtained in the present study coincide with the histological findings. The severity of the pathological findings, such as dilatation, congestion, haemorrhage, oedema and polymorphonuclear nuclear leukocytes (PMNLs), increased in parallel with the increase observed in the products of XO metabolism. In conclusion, exogenously applied ATP prevented I/R damage by reducing the formation of XO in ischemic ovarian tissue.

Neste estudo, a xantina oxidase (XO), o malondialdeído (MDA), mieloperoxidase ( MPO ) e glutationa ( GSH) nos tecidos do ovário de ratos, durante o desenvolvimento de isquemia e reperfusão induzida por pós-isquemia foi investigada, e o efeito de ATP em isquemia e reperfusão (I/R). O dano foi verificado por provas bioquímicas e por histopatologia. Os resultados das análises bioquímicas mostraram que o ATP reduziu significativamente o nível de XO e MDA e aumentou a quantidade de GSH em ambas as isquemia e no tecido do ovário de I / R - aplicado nas doses administradas. Além disso, o ATP suprimiu significativamente o aumento na atividade de MPO que ocorreu na sequência da aplicação de pós-isquemia reperfusão no tecido ovariano. Os resultados bioquímicos obtidos no presente estudo coincidem com os achados histológicos. A gravidade dos achados patológicos, como a dilatação, congestão, hemorragia, edema e polimorfonucleares leucócitos nucleares (PMNLs), aumentou em paralelo com o aumento observado nos produtos do metabolismo XO. Em conclusão, aplicando exogenamente ATP impedido de I/R, houve danos pela redução da formação de tecido de ovário de XO na isquemia.