Influence of treatment with intranasal corticosteroids on the nasal mucosa, weight, and corticosteroid concentration in rats.

BACKGROUND: The effect of intranasal corticosteroids on the nasal epithelium mucosa is an important parameter of treatment safety. This study was designed to examine whether treatment with topical corticosteroids in patients with allergic rhinitis causes atrophic nasal mucosal changes, when compared with systemic corticosteroids, in rats. METHODS: Male Wistar rats were treated daily during 7 weeks with topical administration with 10 microliters of normal saline (control group), 10 microliters of mometasone furoate group, 10 microliters of triamcinolone acetonide (T group), and 8 mg/kg of daily subcutaneous injections of methylprednisolone sodium succinate (MP group). Body weight was evaluated weekly. At the end of the treatment, rats were killed by decapitation to collect blood for determination of corticosterone levels and nasal cavities were prepared for histological descriptive analyses. RESULTS: Treatment with T and MP decreased body weight. Plasma corticosterone concentration was significantly reduced by MP treatment and presented a clear tendency to decrease after T treatment. Histological changes observed in group T included ripples, cell vacuolization, increase in the number of nuclei, and decrease in the number of cilia in the epithelial cells. CONCLUSION: Growth and corticosterone concentration were impaired by T and MP at the same proportion, suggesting a role of this hormone in body gain. With the exception of T, intranasal or systemic treatment with the corticosteroids evaluated in this study did not affect nasal mucosa.

Bioactive glass efficacy in the periodontal healing of intrabony defects in monkeys.

The purpose of this study was the histomorphologic analysis of the efficacy of bioactive glass particles with a narrow size range (Biogran) in the periodontal healing of 2-wall intrabony defects in monkeys. The 2-wall defects were made in the mesial area of the left and right second premolars of four monkeys, filled with gutta-percha and, after 15 days, they were debrided and either naturally filled with coagulum (control) or implanted with bioactive glass (test). In the control sites, the junctional epithelium migrated up to the base of the defect. The presence of newly formed cementum was more significant in the test defects. Both control and test sites showed newly formed bone at the base of the defect. The test defects presented foci of newly formed bone around and within the glass particles localized in the middle third, distant from the defect walls. Histologic analysis showed that the 300- to 355-microm bioactive glass particles aided new periodontal insertion. In conclusion, the tested bioactive glass had better healing potential than debridement only. The graft material showed a promising inhibition of apical migration of the junctional epithelium and greater cementum deposition on the radicular surface of the intrabony defects. The replacement of bioactive glass particles by new bone occurred due not only to an osteoconductive property, but also to an osteostimulatory capacity. Future investigations should evaluate this potential comparatively or together with other grafting materials, regenerative techniques and biological modifiers, as well as assess the longitudinal stability of the new attachment.

Alcohol intake and osseointegration around implants: a histometric and scanning electron microscopy study.

Alveolar wound healing can be modified by local and systemic factors. The aim of this study was to evaluate the possible effect of alcoholic beverage administration (sugarcane brandy) on reparative bone formation around hydroxyapatite/tricalcium phosphate implants inside the alveolar socket. Male Wistar rats had their upper right incisors extracted and the bioceramic granules implanted in the alveoli. The animals received increasing concentrations of brandy until 30 degrees Gay-Lussac was achieved starting 30 days before dental extraction and maintained for periods varying from 1 hour to 6 weeks, until sacrifice. Blood alcohol concentration analysis was performed as well as histological and histometric analysis through light and scanning electron microscopy to examine the relation between alveolar healing components, including new bone trabeculae, and the implants. Blood alcohol concentration was significantly higher in treated animals compared with controls. A significant delay in reparative bone formation was detected in the alveolus of alcoholic rats by a histometric differential point counting method, whereas the presence of the bioceramic in the alveolar socket improved alveolar wound healing in alcohol-treated rats. It is suggested that the osteoconductive properties of this bioceramic accelerated alveolar wound healing in alcoholic rats.

Glass-ionomer cement and bone repair in prolonged immobilization-induced stress / Ionômero de vidro e reparo ósseo durante o estresse por imobilização prolongada

O cimento de ionômero de vidro é um material odontológico que pode ser usado para substituir tecido ósseo, porque apresenta biocompatibilidade e induz osteogênese no processo alveolar em ratos normais. O presente trabalho teve o objetivo de avaliar o comportamento do reparo ósseo em ratos estressados implantados com ionômero de vidro. Os animais foram divididos em três grupos: controle, estressados e estressados tratados com benzodiazepínico injetado intraperitonealmente a uma dose de 5mg/kg (Valium®) uma hora antes da imobilização. Um grânulo de ionômero de vidro foi implantado nos alvéolos imediatamente após a extração dos incisivos superiores direitos. Os animais foram sacrificados 7, 15, 21 e 42 dias após a cirurgia, e as pe'cas, descalcificadas e processadas para a histologia. O estresse foi demonstrado pelos níveis de corticosterona no plasma sanguíneo, os quais aumentaram de 6 a 33 vezes nos ratos submetidos à imobilização. O exame histológico demonstrou que os grânulos de ionômero de vidro foram biocompatíveis e progressivamente incorporados durante o processo de reparo, modificado apenas pela condição de estresse. O volume percentual de osso neoformado no interior do alvéolo foi quantificado por método diferencial de contagem de pontos. O grupo estressado apresentou um atraso na neoformação óssea quando comparado ao controle e ao estressado tratado com diazepan. O tratamento com diazepan levou a uma melhora no reparo dos animais estressados implantados

Histometric study of socket healing after tooth extraction in rats treated with diclofenac

The purpose of the present study was to investigate if diclofenac administration interferes with the time course of alveolar wound healing in rats. Forty-two Wistar rats were used, 21 rats received 10 mg/kg/day of diclofenac one day before and 4 days after extraction of the right maxillary incisors and 21 rats received saline. The animals were sacrificed 7, 14 and 21 days after tooth extraction. Progressive new bone formation and a decrease in the volume fraction of blood clot and connective tissue from 1 to 3 weeks after tooth extraction was quantified using the histometric point-counting method. Diclofenac treatment caused a significant delay in new bone formation in association with an impairment of blood clot remission/organization.

Implante de um floculado de resina de mamona em alvéolo dental de rato / Implantation of flakes of castor oil resin in rat dental alveolus

Os objetivos do presente trabalho foram: 1) testar a biocompatibilidade de uma resina natural, derivada do óleo de mamona, implantada na cavidade de extraçäo dental de ratos, e 2) estudar a possível interferência do material na cronologia do reparo alveolar. O material (AUG-EX, Poliquil Araraquara Polímeros Químicos Ltda., Araraquara - SP) foi implantado no alvéolo imediatamente após a extraçäo do incisivo superior direito e os ratos foram sacrificados de 1 a 6 semanas após a extraçäo ou extraçäo + implante. As hemimaxilas foram descalcificadas e processadas para inclusäo em parafina e obtençäo de cortes semi-seriados, corados com hematoxilina-eosina. Os flocos da resina, de forma irregular e tamanho variável, localizaram-se entre os terços alveolares médio e cervical, inicialmente circundados por tecido de granulaçäo e a seguir por quantidade progressivamente maior de tecido ósseo, no geral com a presença de um tecido conjuntivo interposto, mas em algumas áreas estabelecendo aparente osseointegraçäo direta. Näo houve persistência da reaçäo inflamatória, mas observou-se pequena quantidade de células gigantes aderidas à superfície do material, em todos os períodos. A análise histométrica (contagem diferencial de ponto) do terço apical mostrou um atraso de 13 por cento a 20 por cento no reparo alveolar dos ratos implantados, com menor neoformaçäo óssea associada a maiores volumes percentuais de tecido conjuntivo e de remanescentes do coágulo sangüíneo

Histometric analysis of rat alveolar wound healing following immediate implantation of a biocompatible osteoconductive polymer (BOP) / Análise histométrica da cicatrizaçäo alveolar no rato após a implantaçäo imediata de um polímero osteocondutivo biocompatível (BOP)

O presente trabalho teve por objetivo avaliar quantitativamente a biocompatibilidade de grânulos do polímero osteocondutor biocompatível (BOP), implantados imediatamente após a extraçäo de incisivos superiores direitos de ratos, bem como a cronologia do preparo alveolar frente ao material implantado. Utilizou-se uma câmara clara para estimar a fraçäo de volume ocupada pelo polímero e pelos tecidos conjuntivo e ósseo, por um método diferencial de contagem de pontos, de 1 a 6 semanas após a cirurgia. O exame histológico mostrou grânulos regulares de BOP preenchendo parcialmente o terço médio alveolar. O materialfoi parcialmente reabsorvido e, sendo biocompatível, foi progressivamente integrado integrado no osso alveolar reparacional. A comparaçäo com alvéolos controles, no entanto, mostrou que a presença de BOP no terço médio provocou uma diminuiçäo pequena, porém estatisticamente significante, na neoformaçäo óssea nos terços apical e cervical

Histometric analysis of rat alveolar wound healing / Análise histométrica da cicatrização de ferida em alveolos de ratos

The chronology of alveolar wound healing was analyzed by a standard stereological method (point-couting volumetry) in normal rats. The upper right incisors were extracted and the animals were killed 1, 2, 3 and 6 weeks postoperatively. A light camera was used to determine the volume fraction of histologic components in the apical, middle and cervical thirds of the alveolus. Progressive bone neoformation was quantified, in parallel to a decrease in percent volume of connective tissue. A significantly smaller volume fraction of bone trabeculae in the cervical third of the socket was observed at all periods except the 6th week. The present histometric data show that bone neoformation continued to proceed beyond the 3rd postoperative week

Histological evaluation of the biocompatibility of a glass-ionomer cement in rat alveolus / Evolução histológica da biocompatibilidade do cimento de ionômero de vidro no alveolo de rato

A type III glass-ionomer cement (Vidrion F), currently used as fast-setting lining material and fissure sealant, was implanted into rat dental alveolus immediately after tooth extraction and its biocompatibility was analysed in terms of incorporation into alveolar bone in the wound healing process. Histological and histometric evaluation of trial areas adjacent to the implants showed that by week 1 the glass-ionomer granules were encircled by a conspicuous capsule surrounded by immature connective tissue. By week 3 the implants were surrounded by a less prominent fibrous capsule and most of the tested area was occupied by mature trabecular bone. By week 6 the fibrous capsule was thinner and the tested area was almost totally covered by bone, which was in close contact with the implanted material in several places. Quantitative data confirmed progressive new bone formation in parallel with a decrease in the percentage fraction of connective tissue in the trial areas around the implants. The results revealed that the tested material is biologically compatible, being progressively incorporated into alveolar bone in the wound healing process. The quantitative evaluation of alveolar wound healing around a glass-ionomer implant may provide an experimental model for future comparative studies carried out with other biomaterials

Estudo estereológico das alteraçöes determinadas pelo etanol nas glândulas salivares submandibular e parótida do rato / Stereological study of the alterations induced by ethanol on rat submandibular and parotid salivary glands

Foi realizado um estudo estereológico com o objetivo de determinar os efeitos do consumo prolongado de etanol na estrutura das glândulas salivares de ratos bem nutridos. Animais mantidos com uma dieta sólida semi-sintética enriquecida e álcool, correspondendo a 35 por cento de ingestäo calórica total, desenvolveram alteraçöes estruturais marcantes nas glândulas salivares. Foram observadas atrofia com fibrose intersticial e infiltraçäo gordurosa. Essas alteraçöes foram avaliadas estereologicamente

Tropismo tissular de diferentes cepas do Trypanosoma cruzi. V. Estudo histopatológico das alterações da glândula parótida de camundongos infectados com a cepa RC / Histopathological study of the alterations on mouse parotid gland infected by RC strain of the Trypanosoma cruzi

Os autores examinaram morfológica e morfometricamente a glândula parótida de camundongos inoculados com a cepa RC do Trypanosoma cruzi, na fase aguda da infecção. As células acinares mostraram-se com eosinofilia reduzida, cromatina condensada, núcleos menores e deslocados para o polo basal, além de luz reduzida. Os ductos estão dilatados e com células mais baixas. Os septos conjuntivos estão aumentados e com intenso infiltrado linfoplasmocitário. Formas amastigotas estão presentes nas células acinares e ductulares, no tecido conjuntivo inter e intralobular, no músculo dos vasos sangüíneos e dentro da luz dos ductos estriados

Inervaçäo peptidérgica do sistema reprodutor masculino de mamíferos / Peptidergic innervation of mammalian male genitalia

O sistema reprodutor masculino dos mamíferos é ricamente inervado por fibras do sistema nervoso autônomo simpático e parassimpático. Trabalhos recentes da literatura científica descrevem a ocorrência de nervos autônomos näo-colinérgicos e näo-adrenérgicos, em que os neurotransmissores ou neuromoduladores säo polipeptídios. Os nervos peptidérgicos têm ampla ocorrência no organismo dos mamíferos, e vários deles foram observados no sistema reprodutor masculino. O presente trabalho apresenta uma revisäo da literatura científica acerca da ocorrência, distribuiçäo, origem e funçäo dos neuropeptidios na genitália masculina de mamíferos