Nanohydroxyapatite/Titanate Nanotube Composites for Bone Tissue Regeneration.

Strategies for the production of new nanocomposites that promote bone tissue regeneration are important, particularly those that enhance the osteoinduction of hydroxyapatite in situ. Here, we studied and report the synthesis of nanohydroxyapatite and titanate nanotube (nHAp/TiNT) composites formulated at different concentrations (1, 2, 3, and 10 wt % TiNT) by means of a wet aqueous chemical reaction. The addition of TiNT affects the morphology of the nanocomposites, decreasing the average crystallite size from 54 nm (nHAp) to 34 nm (nHAp/TiNT10%), while confirming its interaction with the nanocomposite. The crystallinity index (CI) calculated by Raman spectroscopy and XRD showed that the values decreased according to the increase in TiNT concentration, which confirmed their addition to the structure of the nanocomposite. SEM images showed the presence of TiNTs in the nanocomposite. We further verified the potential cytotoxicity of murine fibroblast cell line L929, revealing that there was no remarkable cell death at any of the concentrations tested. In vivo regenerative activity was performed using oophorectomized animal (rat) models organized into seven groups containing five animals each over two experimental periods (15 and 30 days), with bone regeneration occurring in all groups tested within 30 days; however, the nHAp/TiNT10% group showed statistically greater tissue repair, compared to the untreated control group. Thus, the results of this study demonstrate that the presently formulated nHAp/TiNT nanocomposites are promising for numerous improved bone tissue regeneration applications.

In vivo evaluation of bone repair guided with biological membrane based on polyhydroxybutyrate and norbixin.

The present work aimed to synthesize and verify the effectiveness of the polyhydroxybutyrate and norbixin membrane as a scaffold in bone defects induced in the tibia of rats. Twenty-four male Rattus norvegicus rats were used, divided into control and membrane groups. After anesthesia, a bone defect was induced in the right tibia, followed by the implantation of the biomaterial at the site of the lesion only in the membrane group, with euthanasia after 15 and 30 days of the experiment. The deposition of organic and inorganic matrix, the quality of newly formed bone tissue and the morphology of the bone defect were measured. After 15 days of the experiment, the biomaterial significantly influenced the deposition of hydroxyapatite crystals, the formation of collagen I matrix and mineralization content in relation to the control group, in addition to the abbreviation of the inflammatory process and superior quality of the newly formed bone tissue. After 30 days, only the membrane group had fully completed its repair process. The biomaterial acted as a scaffold in the regeneration of the guided bone defect by accelerating the synthesis of collagen matrix, mineralization content, density, and maturity when compared to the control group.

Acute autonomic effects of rose oxide on cardiovascular parameters of Wistar and spontaneously hypertensive rats.

AIMS: Anti-inflammatory molecules, such as rose oxide (RO), are likely to exert therapeutic effects in systemic arterial hypertension (SAH), a disease associated with abnormal immune responses. We aimed to investigate acute autonomic effects of RO on hemodynamic parameters of Wistar and spontaneously hypertensive rats (SHR). METHODS: Rats were anesthetized and femoral artery and veins were cannulated. Next day, blood pressure (BP) and heart rate (HR) were recorded. Acute effects of RO (1.25, 2.5, or 5.0 mg/kg; iv) on BP, HR, and variability of systolic arterial pressure (SAP) and pulse interval (PI) were assessed. The effects of RO were also investigated in SHR, which received atropine (2 mg/kg), propranolol (4 mg/kg), or hexamethonium (20 mg/kg) 15 min before receiving RO. Vasorelaxant effects of RO (10-10 to 10-4 M) on aortic rings of rats were also assessed. KEY FINDINGS: In Wistar rats, none of the RO doses evoked significant changes in BP, HR, and variability of SAP and PI. On the other hand, in SHR, RO elicited reduction in mean arterial pressure (MAP), and prevented the increase in the low frequency power (LF) of the SAP spectra. Pretreatment with atropine or propranolol did not alter hypotension, but attenuated RO-induced bradycardia. Hexamethonium prevented RO-induced hypotension and bradycardia. RO exerted vasorelaxant effects on aortic rings with (Wistar and SHR) or without functional endothelium (SHR only). SIGNIFICANCE: Rose oxide, a monoterpene with anti-inflammatory properties, acts as an antihypertensive molecule due to its ability to acutely promote hypotension and bradycardia in spontaneously hypertensive rats.

Anti-inflammatory action of the Ovis aries lipidic fraction associated to therapeutic ultrasound in an experimental model of tendinitis in rats (Rattus norvegicus).

BACKGROUND: Studies have demonstrated the beneficial effects of topical application of fatty acids as healing agents. The lipid fraction of Ovis aries have an anti-inflammatory action that accelerates the healing process. Ultrasound increases blood flow and the extensibility of collagen structures and tendons. OBJECTIVES: To assess the anti-inflammatory action of the Ovis aries lipid fraction associated to pulsed therapeutic ultrasound and friction in an induced tendinitis model. METHODS: Fifty Wistar rats were divided into four groups: control that consisted of Ovis aries gel for topical use; pulsed ultrasound plus oil free sterile lotion; pulsed ultrasound plus Ovis aries gel; and oil free sterile lotion for topical use alone. To induce tendinitis a 10 µL intratendinous injection of collagenase was injected into the right Achilles tendon of rats. Treatment consisted of daily applications of ultrasound using the following parameters: 10% pulsed mode, 10% pulsed frequency of 1 MHz and intensity of 0.5 W/cm² for seven or fourteen days. RESULTS: After 7 days of treatment, only the Ovis aries plus ultrasound group showed statistically significant difference when compared to the control group.The variation in the number of inflammatory cells on animals treated for fourteen days for the control, ultrasound plus oil free, ultrasound plus Ovis aries, Ovis aries plus massage and massage plus oil free groups were statistically significant different, p<0.01. It was observed in animals treated for seven days that the ultrasound plus Ovis aries group was statistically significant better than the control group, p<0.05. CONCLUSION: It can be concluded that treatment using ultrasound plus Ovis aries is more effective than other treatments as it produces significantly better reduction on the number of inflammatory cells at 7 and 14 days.

Ação anti-inflamatória da fração lipídica do Ovis aries associado ao ultrassom terapêutico em modelo experimental de tendinite em ratos (Rattus norvegicus) / Anti-inflammatory action of the Ovis aries lipidic fraction associated to therapeutic ultrasound in an experimental model of tendinitis in rats (Rattus norvegicus)

CONTEXTUALIZAÇÃO: Estudos demonstram o efeito benéfico da aplicação tópica de ácidos graxos como agentes cicatrizantes. A fração lipídica do Ovis aries apresenta uma ação anti-inflamatória que acelera o processo de cicatrização. O ultrassom aumenta o fluxo sanguíneo bem como a extensibilidade das estruturas de colágeno e tendões. OBJETIVOS: Analisar a ação anti-inflamatória da fração lipídica do Ovis aries associado ao ultrassom terapêutico (UST) pulsado e à fricção em modelo de tendinite induzida. MÉTODOS: Cinquenta ratos Wistar foram distribuídos nos seguintes grupos: controle, gel Ovis aries - uso tópico - UST pulsátil + loção estéril (oil free), UST pulsátil + gel Ovis aries, loção estéril (oil free) - uso tópico. Para induzir a tendinite, utilizou-se uma injeção intratendínea de 10µL de colagenase no tendão do calcâneo direito. O tratamento consistiu em aplicações diárias de ultrassom, com os seguintes parâmetros: modo pulsado 10 por cento, frequência de 1 MHz, pulsátil a 10 por cento com intensidade de 0,5W/cm², durante sete ou 14 dias. RESULTADOS: A variação do número de células inflamatórias, para os animais tratados por 14 dias, com relação aos grupos controle, UST + oil free e UST + Ovis aries, apresentou resultados significativos p<0,001. O grupo Ovis aries + massagem e o grupo massagem + oil free apresentaram resultados significativos, p<0,01. Nos animais tratados por sete dias, observou-se que o grupo UST + Ovis aries, em relação ao controle, é estatisticamente significativo, p<0,05 CONCLUSÃO: Pode-se concluir que o tratamento com UST + Ovis aries é mais efetivo que os outros tratamentos, visto que consegue reduzir o número de células inflamatórias no tempo de sete e 14 dias.

BACKGROUND: Studies have demonstrated the beneficial effects of topical application of fatty acids as healing agents. The lipid fraction of Ovis aries have an anti-inflammatory action that accelerates the healing process. Ultrasound increases blood flow and the extensibility of collagen structures and tendons. OBJECTIVES: To assess the anti-inflammatory action of the Ovis aries lipid fraction associated to pulsed therapeutic ultrasound and friction in an induced tendinitis model. METHODS: Fifty Wistar rats were divided into four groups: control that consisted of Ovis aries gel for topical use; pulsed ultrasound plus oil free sterile lotion; pulsed ultrasound plus Ovis aries gel; and oil free sterile lotion for topical use alone. To induce tendinitis a 10µL intratendinous injection of collagenase was injected into the right Achilles tendon of rats. Treatment consisted of daily applications of ultrasound using the following parameters: 10 percent pulsed mode, 10 percent pulsed frequency of 1 MHz and intensity of 0.5 W/cm² for seven or fourteen days. RESULTS: After 7 days of treatment, only the Ovis aries plus ultrasound group showed statistically significant difference when compared to the control group.The variation in the number of inflammatory cells on animals treated for fourteen days for the control, ultrasound plus oil free, ultrasound plus Ovis aries, Ovis aries plus massage and massage plus oil free groups were statistically significant different, p<0.01. It was observed in animals treated for seven days that the ultrasound plus Ovis aries group was statistically significant better than the control group, p<0.05. CONCLUSION: It can be concluded that treatment using ultrasound plus Ovis aries is more effective than other treatments as it produces significantly better reduction on the number of inflammatory cells at 7 and 14 days.