Treatment of fibrinolytic alveolitis with rifamycin B diethylamide associated with gelfoam: a histological study.

The most common complication in the healing of extraction wounds is fibrinolytic alveolitis, which may also be termed dry socket. Reduction in the incidence of this condition after the application of topical antibiotics and the use of systemic antibiotics has been reported. A histological study of disturbed alveolar socket healing in rats was carried out to analyze the influence of application of rifamycin B diethylamide (Rifocin M) associated or not with Gelfoam. Sixty-four male rats (Rattus norvegicus albinus, Wistar), weighing 120-150 g, were divided into 4 groups of 16 animals each. In the second group of rats which received implants of Gelfoam, there was an intense resorption of bone walls in the initial stage. The rats that received implants of Gelfoam saturated with Rifocin M (fourth group) showed better results than the second group. The third group (only irrigation with rifamycin) showed better bone formation in the alveolar socket compared to the first, second and fourth groups. Thus, these results showed that rifamycin irrigation is useful in the control of alveolar infections.

Ultrastructural changes on the epithelial cells of uterine tubes of Wistar rats after chronic ethanol ingestion

The present paper describes the morphological alterations of the epithelial layer of the uterine tubes of rats submitted to experimental chronic alcoholism using anatomical, histological, ultrastructural and morphometric methods. Sixty adult rats (Rattus norvegicus albinus) at the same age (3 months) and with a mean body weight of 228 g were divided into two groups. The control group received solid diet (Purina rat chow) and tap water ad libitum. The alcoholic group received the same solid diet and was allowed to drink only sugar cane brandy dissolved in 30° Gay Lussac (v/v). After periods of 90, 180 and 270 days of treatment animals at normal estrus were anaesthetised with ethyl ether, weighed and sacrificed. Subsequently, the uterine tubes were dissected, weighed and prepared for TEM and SEM methods. The final mean body weights were similar in the control and alcoholic groups. The morphometric analysis showed no difference between control and alcoholic epithelial height. The alcoholic animals showed ultrastructural alterations: intense lipid droplet and lysosomes accumulation, dilated rough endoplasmic reticulum cisternae and vacuolization in both periods of treatment. It was concluded that alcohol acts as a toxin on the epithelial layer of the uterine tubes of rats.

Ultrastructural and morphometric analysis on the ovary of Wistar rats after chronic ethanol ingestion

In the present study, seventy-two adult rats (Rattus norvegicus albinus) aged three months were used. The animals were divided into two groups (control and alcoholic). The control group received a solid diet (Purina rat chow) and tap water ad libitum. The alcoholic group received the same solid diet and sugar-cane liquid (trade 51, 41° Gay Lussac - GL) diluted 30° GL. At the end or 90, 180 and 270 days of treatment, ten rats of each group were anaesthetized with ethyl ether and sacrificed. The ovaries were collected, fixed, included and submitted to analysis by both light and electron microscopy. The alcoholic group showed increase in the number of corpora lutea at both 180 and 270 days of treatment, atresic follicles at 270 days of treatment, decreased diameter of corpora lutea at 180 and 270 days of treatment, the granulosa layer of the antral follicles at 180 days of treatment, and gradual regression of the theca antral follicles. Furthermore, an increase in diameter and posterior regression of the antral follicle were observed, as well as vacuolation, increased lipid droplets in the granulosa cell at 90 days and in the theca at 180 and 270 days of treatment and gradually in the interstitial cell. The rats showed ovarian alterations after ingestion of alcohol. There was a correlation between exposure time to the drug and the injury observed.

Histological investigation of a 10% metronidazole and 2% lidocaine dressing on wound healing in rats.

AIM: Alveolitis is considered a disturbance of the alveolar healing process that is characterized by blood clot disintegration, alveolar wall infection and extreme pain. Several substances have been investigated to improve healing and guarantee postoperative comfort to patients. The aim of this study was to evaluate, microscopically, in rats, the healing process in non-infected tooth sockets, after application of a 10% metronidazole and 2% lidocaine dressing, using lanolin as vehicle and mint as flavoring. METHODS: Forty-five rats (Rattus norvegicus albinus, Wistar) had their right incisor extracted and were randomly assigned to 3 groups (n=15): Group I (control): the sockets were filled with blood clot; Group II: application of adrenaline solution at 1:1 000 with an absorbent paper point during 1 min plus filling of the socket with a 10% metronidazole and 2% lidocaine dressing, with lanolin as vehicle, and mint as flavoring; Group III: filling of the socket with the 10% metronidazole and 2% lidocaine dressing, with lanolin as vehicle and mint as flavoring. After 6, 15 and 28 days postoperatively, 5 animals per group were euthanized with an injectable anesthetic overdose. Histological and statistical analyses were performed. RESULTS: The results showed that the 10% metronidazole and 2% lidocaine dressing with lanolin as vehicle and mint as flavoring yielded similar response as that of the normal repair group and may be used to prevent the onset of alveolitis in those cases in which any predisposing factor is present. CONCLUSIONS: The use of this dressing has shown a good postoperative patient's comfort and does not cause a significant delay in the alveolar healing process.

Experimental model of pulmonary carcinogenesis in Wistar rats

Purpose: To elaborate an experimental model of pulmonary carcinogenesis in Wistar rats. Methods: Male Rattus norvegicus albinus, Wistar lineage was carried through an intra-pulmonary instillation of the Benzo[a]pyrene (B[a]P) dilution in alcohol 70%, a polycyclic aromatic hydrocarbon widely known by its power of tumoral induction. Three experimental groups had been formed with 08 animals each: Control Group (Alcohol 70%); B[a]P Group 10 mg/kg; e B[a]P Group 20mg/ kg, submitted to euthanasia 08, 10, 12 and 14 weeks after the experimental procedure. The pulmonary sections had been colored by hematoxilin-eosin (HE) and submitted to the morphometrical analysis to describe the tissue alterations. Results: The presence of diffuse inflammatory alterations was observed in all groups, however, at the analysis of the pulmonary tissue of the experimental groups, it had been observed hyperplasic alterations (BALT hyperplasia), and in one of the animals of the experimental group 20mg/kg (12 weeks), it was noticed the presence of cellular epithelial tracheal pleomorphism, suggesting the adenocarcinoma formation in situ. Conclusion: The main secondary alterations to the intra-pulmonary instillation of B[a]P in Wistar rats were: cellular proliferation, inflammatory alterations of several degrees and nodular lymphoid hyperplasias. The association of an activator agent of the pulmonary metabolic reply is necessary to establish the ideal reply-dose to the development of the lung cancer.

Root surface treatment with vitamin C in tooth replantation: microscopic study in rats

AIM: Late tooth replantation is a worthy procedure, especially in growing patients, being the best option for tooth avulsion. This study evaluated the effects of root surface treatment with 2% acidulated phosphate sodium fluoride and effervescent vitamin C (Redoxon) in late replantation. METHODS: Twenty rat teeth (Rattus norvegicus, albinus, Wistar) were extracted and left on a table for 6 h. Then, the dental papilla and enamel organ were sectioned and the pulp was removed through the apex. After removal of the periodontal ligament with a blade, the animals were divided into 2 groups: Group I teeth were immersed in 2% acidulated phosphate sodium fluoride solution for 10 min and obturated with Ca(OH)(2) paste. Group II teeth were immersed in effervescent vitamin C solution (Redoxon 2 g) for 10 min and obturated as for Group I. After these procedures, teeth were replanted and animals were killed after 60 days. RESULTS: The study revealed a larger amount of replacement resorption in Group I and larger amount of ankylosis in Group II, with statistically significant difference and absence of inflammatory resorption. CONCLUSION: The substances used for root surface treatment were unable to prevent replacement resorption and ankylosis, which are expected when the periodontal ligament has been lost.

Alterações da densidade mineral óssea em vértebras de ratos wistar submetidos à ausência de carga nos membros pélvicos

The suspension of rats by the tail model is used to investigate the behavior of bone in animals unable to move around. Bone is an adaptative tissue that develops in structure and function, among other factors, in response to mechanical forces applied to it and metabolic demands that it will suffer. The absence of mechanical forces and deformation of bone that occurs causes a decrease in calcium deposition in the absence of stimuli on osteoblasts and osteocytes, favoring the action of osteoclasts, making bones weak and brittle. Therefore, the mechanical action is necessary to stimulate local bone response and thus provide growth and remodeling. The aim of this study was to evaluable by radiographic densitometry, the tail suspension for 15 and 36 days alter the bone mineral density of cervical vertebrae (C3), thoracic (T6) and lumbar (L1 and L3) of Wistar rats. Thirty Rattus norvegicus albinus, adult, male, Wistar strain, average body mass ± 350g, were divided into 3 groups: control (n = 10) - not suspended; S15 (n = 10) - suspended for 15 days and S36 (n = 10) - suspended for 36 days. For densitometric analysis vertebrae were radiographed, scanned, digitized and analyzed by the computer program ImageJ®. There was a statistically significant increase in bone mineral density in group S15, probably by the restlessness of the animals to the suspension, with a decrease in group S36, and this hypothetically is linked to the accommodation of the rats, concluding that the tail suspension altered bone mineral density in first time with a decrease over time.

Pulpal and periodontal diseases increase triglyceride levels in diabetic rats

Objectives: The aim of this study was to evaluate triglyceride and cholesterol levels in diabetic rats and their relationship with pulpal and periodontal diseases. Methods: Eighty male rats (Rattus norvegicus albinus, Wistar) were divided into the following eight groups comprising ten animals each: normal rats (G1), rats with pulpal diseases (G2), rats with periodontal diseases (G3), rats with both pulpal and periodontal diseases (G4), diabetic rats (G5), diabetic rats with pulpal diseases (G6), diabetic rats with periodontal diseases (G7), and diabetic rats with both periodontal and pulpal diseases (G8). Diabetes was induced by injecting streptozotocin, periapical lesions were induced by exposing pulpal tissue to the oral environment, and periodontal diseases were induced by periodontal ligature. The animals were killed after 30 days, and lipid profile was enzymatically measured using Trinder's method. The total assessed values were statistically analyzed by analysis of variance and Tukey test (p < 0.05). Results: The triglyceride levels of diabetic rats with periodontal disease and of diabetic rats with both periodontal and pulpal diseases were significantly higher than those of normal rats and nondiabetic group rats, respectively. The differences in the cholesterol levels among the groups were not significant. Conclusions: We found that the association of pulpal and periodontal diseases with diabetes increased triglyceride levels in rats. Clinical significance: Changes in lipid profile may be related to the presence of oral infections and diabetes. © 2012 Springer-Verlag Berlin Heidelberg.

Expression of opg, rank, and rankl proteins in tooth repair processes after immediate and delayed tooth

This study evaluated the immunohistochemical expression of OPG, RANK, and RANKL proteins in the repair after immediate and delayed replantation of rat teeth. Fifty-six Wistar rats (Rattus norvegicus albinus) had their maxillary right lateral incisor extracted and then replanted, according to the following conditions: group I (control; n = 8), teeth were not extracted; group II (n = 16), immediate replantation; group III (n = 16), delayed replantation without treatment; and group IV (n = 16), delayed replantation after root surface treatment (periodontal ligament removal and immersion in 2% acidulated-phosphate sodium fluoride) and calcium hydroxide intracanal dressing. Rats in group I were euthanized on the first day of the experiment, while the animals in the other groups were euthanized 10 and 60 days after replantation (n = 8/period). Hematoxylin and eosin-stained sections were obtained for histological analysis. The immunohistochemical analysis revealed expression of OPG and RANKL proteins in all groups and both postreplantation times, except for group II at 60 days. In the experimental groups, RANK expression was observed only at 10 days. In conclusion, there was strong immunostaining for the OPG-RANK-RANKL system at the earlier postreplantation time, suggesting a more effective participation of these proteins at the start of the healing process, as their expression decreased at 60 days. Copyright © 2013 by Mutaz B. Habal, MD.

Evaluation of the presence of VEGF, BMP2 and CBFA1 proteins in autogenous bone graft: Histometric and immunohistochemical analysis

Aims: The purpose of this study was to evaluate the expression of proteins that participate in the osteoinduction stage (VEGF, BMP2 and CBFA1) of the process of bone regeneration of defects created in rat calvariae and filled with autogenous bone block grafts. Materials and methods: 10 adult male rats (Rattus norvegicus albinus, Wistar) were used, who received two bone defects measuring 5 mm each in the calvariae. The bone defects constituted two experimental groups (n = 10): Control Group (CONT) (defects filled with a coagulum); Graft Group (GR) (defects filled with autogenous bone removed from the contralateral defect). The animals were submitted to euthanasia at 7 and 30 days post-operatively. Results: Quantitative analysis demonstrated significantly greater bone formation in Group GR, but the presence of the studied proteins was significantly greater in the CONT Group in both time intervals of observation. Conclusion: It was not possible in this study in cortical bone block groups to detect the osteoinductive proteins in a significant amount during the repair process. © 2013 European Association for Cranio-Maxillo-Facial Surgery.

Effect of the treatment of root surface-adhered necrotic periodontal ligament with propolis or fluoride in delayed rat tooth replantation

Objectives: The purpose of this study was to evaluate the application of 15 % propolis and 2 % acidulated-phosphate sodium fluoride solutions on the root surface-adhered necrotic cemental periodontal ligament in delayed tooth replantation. Materials and methods: Thirty Wistar rats (Rattus norvegicus, albinus) had their right upper incisor extracted and maintained in dry storage for 60 min. After this period, the dental papilla, enamel organ, and pulp tissue were removed, and the animals were randomly assigned to three groups: group I = immersion in saline for 10 min; group II = immersion in a 2 % acidulated-phosphate sodium fluoride solution for 10 min; and group III = immersion in a 15 % propolis and propylene glycol solution for 10 min. The root canals were filled with a calcium hydroxide paste and the teeth were replanted. Results: Inflammatory resorption, replacement resorption, and ankylosis were observed in all groups without a statistically significant difference (p > 0.05) among them. Conclusions: Under the tested conditions, the application of fluoride or propolis on root surface-adhered necrotic periodontal ligament did not favor the healing process in delayed tooth replantation. © 2013 Springer-Verlag Berlin Heidelberg.

Efeito do exercício aeróbio na menopausa induzida por ooforectomia: estudo clínico, biomecânico e densitométrico em ratas

Pós-graduação em Bases Gerais da Cirurgia - FMB

Análise de parâmetros de força e padrão de nado de ratos controles e obesos, a partir de um sistema de aquisição de sinais em natação atada: Influência da intensidade do exercício e da densidade corporal

Pós-graduação em Ciências da Motricidade - IBRC

Hidroterapia e eletroterapia em ratos com denervação do nervo isquiático

Pós-graduação em Ciência Animal - FMVA

Reação tecidual à superfície de titânio tratada pela irradiação laser e hidroxiapatita: análise histomorfométrica em ratos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)