RESUMO

Aim: Breast cancer and its metastases involve high mortality even with advances in chemotherapy. Solid lipid nanoparticles provide a platform for drug delivery, reducing side effects and treatment-induced bone loss. A solid nanoparticle containing doxorubicin was evaluated for its ability to prevent bone loss in a pre-clinical breast cancer model. Methods: We investigated the effects of SLNDox in an aggressive metastatic stage IV breast cancer model, which has some important features that are interesting for bone loss investigation. This study evaluates bone loss prevention potential from solid lipid nanoparticles containing doxorubicin breast cancer treatment, an evaluation of the attenuation of morphological changes in bone tissue caused by the treatment and the disease and an assessment of bone loss imaging using computed tomography and electron microscopy. Results: Chemotherapy-induced bone loss was also observed in tumor-free animals; a solid lipid nanoparticle containing doxorubicin prevented damage to the growth plate and to compact and cancellous bones in the femur of tumor-bearing and healthy animals. Conclusion: The association of solid lipid nanoparticles with chemotherapeutic drugs with proven efficacy promotes the prevention of serious consequences of chemotherapy, reducing tumor progression, increasing quality of life and improving prognosis and survival.

[Box: see text].

RESUMO

Oral bacteria are implicated not only in oral diseases but also in gut dysbiosis and inflammatory conditions throughout the body. The periodontal pathogen Aggregatibacter actinomycetemcomitans (Aa) often occurs in complex oral biofilms with Streptococcus gordonii (Sg), and this interaction might influence the pathogenic potential of this pathogen. This study aims to assess the impact of oral inoculation with Aa, Sg, and their association (Aa+Sg) on alveolar bone loss, oral microbiome, and their potential effects on intestinal health in a murine model. Sg and/or Aa were orally administered to C57Bl/6 mice, three times per week, for 4 weeks. Aa was also injected into the gingiva three times during the initial experimental week. After 30 days, alveolar bone loss, expression of genes related to inflammation and mucosal permeability in the intestine, serum LPS levels, and the composition of oral and intestinal microbiomes were determined. Alveolar bone resorption was detected in Aa, Sg, and Aa+Sg groups, although Aa bone levels did not differ from that of the SHAM-inoculated group. Il-1ß expression was upregulated in the Aa group relative to the other infected groups, while Il-6 expression was downregulated in infected groups. Aa or Sg downregulated the expression of tight junction genes Cldn 1, Cldn 2, Ocdn, and Zo-1 whereas infection with Aa+Sg led to their upregulation, except for Cldn 1. Aa was detected in the oral biofilm of the Aa+Sg group but not in the gut. Infections altered oral and gut microbiomes. The oral biofilm of the Aa group showed increased abundance of Gammaproteobacteria, Enterobacterales, and Alloprevotella, while Sg administration enhanced the abundance of Alloprevotella and Rothia. The gut microbiome of infected groups showed reduced abundance of Erysipelotrichaceae. Infection with Aa or Sg disrupts both oral and gut microbiomes, impacting oral and gut homeostasis. While the combination of Aa with Sg promotes Aa survival in the oral cavity, it mitigates the adverse effects of Aa in the gut, suggesting a beneficial role of Sg associations in gut health.

Assuntos

RESUMO

PURPOSE: This two-arm parallel randomized controlled trial aimed to evaluate and compare periodontal changes due to rapid maxillary expansion (RME) using tooth-bone-borne and tooth-borne devices in growing patients via clinical examinations and cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Forty-two eligible patients (aged 11-14 years; transverse maxillary deficiency, posterior crossbite) were screened and divided into two groups based on the treatment received (randomization was performed using computer-generated numeric sequences): hybrid hyrax tooth-bone-borne group (TBB) and hyrax tooth-borne group (TB). The primary outcome was the change in cortical bone thickness (by CBCT). In addition, the clinical attachment level (CAL), gingival recession, and bleeding were assessed. Both examinations were performed before and 3 months after the activation phase. Intergroup comparisons were performed using analysis of covariance (ANCOVA; P < 0.05). RESULTS: Twenty-one patients (12 girls and 9 boys; mean initial age, 13.3 years) were included in the TBB group and 21 (5 girls and 16 boys; mean initial age, 13.2 years) were included in the TB group. The TB group exhibited a decrease in buccal bone thickness in the first premolars and first molars at all three evaluated levels. Specifically, tooth 14 at 3 mm from the enamel-cement junction showed a significant width reduction (0.7 mm; p < 0.001), accompanied by a notable increase in palatal cortical thickness at 6 mm of enamel-cement junction (1.13 mm; p < 0.001). CONCLUSIONS: RME resulted in buccal bone thickness reduction at the first premolar with hyrax treatment. In the molar region, both devices resulted in cortical bone alterations that were less pronounced in the TBB group.

RESUMO

Therapies to prevent osteoporosis are relevant since it is one of the most common non-communicable human diseases in the world and the most prevalent bone disorder in adults. Since jaboticaba peel extract (JPE) added to the culture medium enhanced the osteogenic potential of mesenchymal stem cells (MSCs) derived from osteoporotic rats, we hypothesized that JPE prevents the development of ovariectomy-induced osteoporosis. Ovariectomized rats were treated with either JPE (30 mg/kg of body weight) or its vehicle for 90 days, starting 7 days after the ovariectomy. Then, the femurs were subjected to microcomputed tomography and histological analyses, and the osteoblast and adipocyte differentiation of MSCs was evaluated. JPE attenuated ovariectomy-induced bone loss, as evidenced by higher bone volume/total volume and trabecular number, along with lower trabecular separation and bone marrow adiposity. These protective effects of JPE on bone tissue are due to its ability to prevent the imbalance between osteoblast and adipocyte differentiation of MSCs, since, compared with MSCs derived from ovariectomized rats treated with vehicle, MSCs treated with JPE exhibited higher gene and protein expression of osteogenic markers and extracellular matrix mineralization, as well as lower gene expression of adipogenic markers. These data highlight the potential therapeutic use of JPE to prevent osteoporosis.

RESUMO

The treatment of Gustilo-Anderson type III open femoral fracture with large segmental bone defect remains a challenge for orthopedic trauma surgeons. The aims of management are first to prevent the risk of infection and then to reconstruct the bone loss with correct alignment and length. The induced membrane technique (or Masquelet technique) was initially described for tibia nonunion but became over the years an established procedure to treat any kind of large bone defect. The case of a 22-year old male who sustained an open femoral shaft fracture with a circumferential 7-cm bone defect after a car accident is presented. Given the critical size of the bone loss, we chose to manage this patient using a modified-Masquelet technique, in which we stabilized the fracture by an intramedullary femoral nail and filled only the lateral side of the defect with a cement spacer. He went on to have a full and successful union of his fracture 16-weeks after the second stage surgery. The final functional outcomes were excellent allowing the patient to resume all activities without restriction.

RESUMO

BACKGROUND: The aim of this study was to evaluate the incidence of preloading crestal bone loss (PLCBL) and to identify the patient-related and implant-related factors associated with PLCBL. METHODS: This retrospective cohort examined the dental records of patients who received at least one dental implant. PLCBL was defined as a reduction ⩾0.5 mm and severe PLCBL (primary variable) as a reduction ⩾1.5 mm in mesial and/or distal bone level, measured from the day of implant placement to uncovering or abutment installation/crown delivery. The incidence of PLCBL and patient and implant variables were recorded. Bivariate analysis and binary logistic regression identified factors associated with PLCBL ⩾0.5 mm and ⩾1.5 mm. RESULTS: A total of 746 dental implants placed in 361 patients from January 2011 to July 2021 was included in the analyses. Of the implants assessed, 24.4% (n = 182) exhibited PLCBL ⩾ 0.5 mm and 10.5% (n = 78) presented severe PLCBL (i.e., ⩾1.5 mm). Males (odds ratio [OR] = 1.85, 95% confidence interval [CI] = 1.11-3.07), patients with diabetes (OR = 3.33, 95% CI = 1.73-6.42), and those allergic to penicillin (OR = 3.13, 95% CI = 1.57-6.22) were more likely to experience severe PLCBL (p < 0.05). Implants placed in the anterior area (OR = 2.08, 95% CI = 1.16-3.73), with bone-level platform-abutment connection (OR = 4.73, 95% CI = 1.94-11.49) and inserted supracrestally (OR = 3.77, 95% CI = 1.84-7.72), presented a greater risk of developing severe PLCBL (p < 0.05). Implants placed in a previously grafted area presented a lower likelihood of developing severe PLCBL (OR = 0.489, 95% CI = 0.28-0.84). CONCLUSION: The incidence of PLCBL ⩾ 0.5 mm and ⩾1.5 mm was 24.4% and 10.5%, respectively. Male sex, diabetes, allergy to penicillin, anterior location, bone-level platform-abutment connection, and supracrestal implant placement are potential risk factors for severe PLCBL. A previously grafted area is a potential protective factor.

RESUMO

INTRODUCTION: Young women with breast cancer (BC) may experience bone mineral density (BMD) loss secondary to cancer treatment effects on estrogen levels. Studies assessing BMD in BC patients have had a limited representation of young women. This multicenter retrospective study analyzed the frequency of low BMD and associated factors in this age group. METHODS: Women diagnosed with stage 0-III BC at ≤40 years, treated with chemotherapy and/or endocrine therapy between 2010 and 2020 at 5 Mexican BC referral centers were eligible. Demographic, clinical and treatment data were collected, as well as bone dual-energy X-ray absorptiometry (DEXA) results. Low BMD was defined as lumbar or femoral neck T-score < -1.0 or Z-score ≤ -2.0. RESULTS: A total of 1259 patients were included; median age at diagnosis was 36 years (21-40). Overall, 93% received chemotherapy and 65% endocrine therapy (tamoxifen was received at some point by 61%, aromatase inhibitors by 17%, and GnRH agonists/bilateral oophorectomy by 21%). DEXA scans were documented in 254 (20%), of which 163 (64%; 95% confidence interval [CI] 58%-70%) had a low BMD report. Low BMD was associated with receiving aromatase inhibitors (Odds ratio [OR] 1.92; 95% CI 1.13-3.24), and GnRH agonists/bilateral oophorectomy (OR 2.25; 95% CI 1.21-4.21). CONCLUSION: The suboptimal frequency of BMD monitoring observed displays an alarming disregard for bone health in young patients. Thus, a high proportion of women with low BMD are potentially being missed and precluded from the opportunity to receive timely interventions. Particular focus should be put on BMD monitoring among patients treated with aromatase inhibitors, GnRH agonists or bilateral oophorectomy.

Assuntos

RESUMO

OBJECTIVE: To evaluate the long-term survival and success rates of implants placed in reconstructed areas using microvascularized or non-microvascularized extraoral bone grafts. MATERIALS AND METHODS: An electronic search was performed in five databases and in gray literature for articles published until June, 2023. The eligibility criteria comprised observational studies (prospective or retrospective) and clinical trials, reporting survival and success rates of implants placed in extraoral bone grafts. A meta-analysis (implant failure) was categorized into subgroups based on the type of bone graft used. The risk of bias within studies was assessed using the Newcastle-Ottawa Scale. RESULTS: Thirty-one studies met the inclusion criteria. The mean follow-up time was 92 months. The summary estimate of survival rate at the implant level were 94.9% (CI: 90.1%-97.4%) for non-vascularized iliac graft, 96.5% (CI: 91.4%-98.6%) for non-vascularized calvaria graft, and 92.3% (CI: 89.1%-94.6%) for vascularized fibula graft. The mean success rate and marginal bone loss (MBL) were 83.2%; 2.25 mm, 92.2%; 0.93 mm, and 87.6%; 1.49 mm, respectively. CONCLUSIONS: Implants placed in areas reconstructed using extraoral autogenous bone graft have high long-term survival rates and low long-term MBLs. The data did not demonstrate clinically relevant differences in the survival, success, or MBL of grafts from different donor areas or with different vascularization. This systematic review was registered in INPLASY under number INPLASY202390004.

Assuntos

RESUMO

Arthritis and periodontitis are inflammatory diseases that share several immunopathogenic features. The expansion in the study of virus-induced arthritis has shed light on how this condition could impact other parts of the human body, including the mouth. Viral arthritis is an inflammatory joint disease caused by several viruses, most notably the alphaviruses Chikungunya virus (CHIKV), Sindbis virus (SINV), Ross River virus (RRV), Mayaro virus (MAYV), and O'nyong'nyong virus (ONNV). These viruses can induce an upsurge of matrix metalloproteinases and immune-inflammatory mediators such as Interleukin-6 (IL6), IL-1ß, tumor necrosis factor, chemokine ligand 2, and receptor activator of nuclear factor kappa-B ligand in the joint and serum of infected individuals. This can lead to the influx of inflammatory cells to the joints and associated muscles as well as osteoclast activation and differentiation, culminating in clinical signs of swelling, pain, and bone resorption. Moreover, several data indicate that these viral infections can affect other sites of the body, including the mouth. The human oral cavity is a rich and diverse microbial ecosystem, and viral infection can disrupt the balance of microbial species, causing local dysbiosis. Such events can result in oral mucosal damage and gingival bleeding, which are indicative of periodontitis. Additionally, infection by RRV, CHIKV, SINV, MAYV, or ONNV can trigger the formation of osteoclasts and upregulate pro-osteoclastogenic inflammatory mediators, interfering with osteoclast activation. As a result, these viruses may be linked to systemic conditions, including oral manifestations. Therefore, this review focuses on the involvement of alphavirus infections in joint and oral health, acting as potential agents associated with oral mucosal inflammation and alveolar bone loss. The findings of this review demonstrate how alphavirus infections could be linked to the comorbidity between arthritis and periodontitis and may provide a better understanding of potential therapeutic management for both conditions.

Assuntos

RESUMO

OBJECTIVE: The objective of the study was to evaluate the expression of oxytocin receptors in normal and inflamed gingiva, as well as the effects of systemic administration of oxytocin in bone loss and gum inflammatory mediators in a rat model of experimental periodontitis. BACKGROUND DATA: Current evidence supports the hypothesis of a disbalance between the oral microbiota and the host's immune response in the pathogenesis of periodontitis. Increased complexity of the microbial biofilm present in the periodontal pocket leads to local production of nitrogen and oxygen-reactive species, cytokines, chemokines, and other proinflammatory mediators which contribute to periodontal tissue destruction and bone loss. Oxytocin has been suggested to participate in the modulation of immune and inflammatory processes. We have previously shown that oxytocin, nitric oxide, and endocannabinoid system interact providing a mechanism of regulation for systemic inflammation. Here, we aimed at investigating not only the presence and levels of expression of oxytocin receptors on healthy and inflamed gingiva, but also the effects of oxytocin treatment on alveolar bone loss, and systemic and gum expression of inflammatory mediators involved in periodontal tissue damage using ligature-induced periodontitis. Therefore, anti-inflammatory strategies oriented at modulating the host's immune response could be valuable adjuvants to the main treatment of periodontal disease. METHODS: We used an animal model of ligature-induced periodontitis involving the placement of a linen thread (Barbour flax 100% linen suture, No. 50; size 2/0) ligature around the neck of first lower molars of adult male rats. The ligature was left in place during the entire experiment (7 days) until euthanasia. Animals with periodontitis received daily treatment with oxytocin (OXT, 1000 µg/kg, sc.) or vehicle and/or atosiban (3 mg/kg, sc.), an antagonist of oxytocin receptors. The distance between the cement-enamel junction and the alveolar bone crest was measured in stained hemimandibles in the long axis of both buccal and lingual surfaces of both inferior first molars using a caliper. TNF-α levels in plasma were determined using specific rat enzyme-linked immunosorbent assays (ELISA). OXT receptors, IL-6, IL-1ß, and TNF-α expression were determined in gingival tissues by semiquantitative or real-time PCR. RESULTS: We show that oxytocin receptors are expressed in normal and inflamed gingival tissues in male rats. We also show that the systemic administration of oxytocin prevents the experimental periodontitis-induced increased gum expression of oxytocin receptors, TNF-α, IL-6, and IL-1ß (p < .05). Furthermore, we observed a reduction in bone loss in rats treated with oxytocin in our model. CONCLUSIONS: Our results demonstrate that oxytocin is a novel and potent modulator of the gingival inflammatory process together with bone loss preventing effects in an experimental model of ligature-induced periodontitis.

Assuntos