Oral implant osseointegration model in C57Bl/6 mice: microtomographic, histological, histomorphometric and molecular characterization

Abstract Despite the successful clinical application of titanium (Ti) as a biomaterial, the exact cellular and molecular mechanisms responsible for Ti osseointegration remains unclear, especially because of the limited methodological tools available in this field. Objective: In this study, we present a microscopic and molecular characterization of an oral implant osseointegration model using C57Bl/6 mice. Material and Methods: Forty-eight male wild-type mice received a Ti implant on the edentulous alveolar crest and the peri-implant sites were evaluated through microscopic (μCT, histological and birefringence) and molecular (RealTimePCRarray) analysis in different points in time after surgery (3, 7, 14 and 21 days). Results: The early stages of osseointegration were marked by an increased expression of growth factors and MSC markers. Subsequently, a provisional granulation tissue was formed, with high expression of VEGFb and earlier osteogenic markers (BMPs, ALP and Runx2). The immune/inflammatory phase was evidenced by an increased density of inflammatory cells, and high expression of cytokines (TNF, IL6, IL1) chemokines (CXCL3, CCL2, CCL5 and CXC3CL1) and chemokine receptors (CCR2 and CCR5). Also, iNOS expression remained low, while ARG1 was upregulated, indicating predominance of a M2-type response. At later points in time, the bone matrix density and volume were increased, in agreement with a high expression of Col1a1 and Col21a2. The remodelling process was marked by peaks of MMPs, RANKL and OPG expression at 14 days, and an increased density of osteoclasts. At 21 days, intimate Ti/bone contact was observed, with expression of final osteoblast differentiation markers (PHEX, SOST), as well as red spectrum collagen fibers. Conclusions: This study demonstrated a unique molecular view of oral osseointegration kinetics in C57Bl/6 mice, evidencing potential elements responsible for orchestrating cell migration, proliferation, ECM deposition and maturation, angiogenesis, bone formation and remodeling at the bone-implant interface in parallel with a novel microscopic analysis.

Expression of lymphatic markers and lymphatic growth factors in psoriasis before and after anti-TNF treatment

BACKGROUND: Angiogenesis is an early stage of psoriatic lesion development, but less is known about lymphagiogenesis and its role in the development of psoriasis. OBJECTIVE: To examine the expression of specific lymphatic markers and lymphatic growth factors in untreated psoriatic skin, in the unaffected skin of patients and skin of healthy volunteers, as well as their alteration after treatment with an anti-TNF agent. METHODS: Immunohistochemistry for the lymphatic markers D2-40 and LYVE-1, in addition to the VEGF-C and VEGF-D growth factors, was performed in the skin biopsies of psoriatic lesions and adjacent non-psoriatic skin of 19 patients before and after treatment with etanercept, as well as in the skin biopsies of 10 healthy volunteers. RESULTS: The expressions of D2-40, VEGF-C and VEGF-D on lymphatic vessels underwent statistically significant increases in untreated psoriatic skin compared with non-lesional skin, in contrast to LYVE-1, which did not involve significant increase in expression in psoriatic skin. VEGF-C expression on lymphatic vessels diminished after treatment with etanercept. Moreover VEGF-C and VEGF-D staining on fibroblasts presented with higher expression in lesional skin than in non-lesional adjacent skin. CONCLUSION: Remodeling of lymphatic vessels possibly occurs during psoriatic lesion development, parallel to blood vessel formation. The exact role of this alteration is not yet clear and more studies are necessary to confirm these results. .

Study on vascular endothelial growth factor and its receptor in the vitreous of diabetic rats / Estudio del factor de crecimiento endotelial vascular y su receptor en el humor vítreo de ratas diabéticas

OBJECTIVE: To investigate the vitreous level of vascular endothelial growth factor (VEGF) and kinase insert domain-containing receptor (KDR) in diabetic rats, and to explore the role of VEGF and KDR in diabetic retinopathy. METHODS: Eighty-four adult Wistar rats were randomly divided into two groups. Fifty-eight rats in group A were injected intraperitoneally with streptozotocin to induce diabetes and 20 rats in group B were injected with physiological saline. Blood glucose meter was used to detect the blood glucose level at 72 hours after injection; blood glucose level >16.67 mmol/L was considered to be successful modelling. Blood glucose level was assayed and body mass was measured on the same modelling day, one week, two weeks and four weeks after modelling. Four weeks after modelling, the vitreous was taken and the VEGF and KDR levels were detected by enzyme-linked immunosorbent assay (ELISA). The eyeballs were fixed with paraform and embedded by petrolin for haematoxylin and eosin (H & E) staining. RESULTS: Forty-two rats survived and 16 rats died in group A. No rats died in group B. The blood glucose at one week, two weeks and four weeks between the two groups had statistical differences (p < 0.05). The weight at one week and two weeks between the two groups was not different but there was statistical difference at four weeks between the two groups (p < 0.01). The ELISA results showed that the VEGF and KDR levels were 0.276 ± 0.026 ng/mL and 2.936 ± 0.295 ng/mL in group A, 0.231 ± 0.021 ng/mL and 2.394 ± 0.227 ng/mL in group B, respectively. The VEGF and KDR levels of group A were higher than those of group B (p < 0.05). CONCLUSIONS: The changes of VEGF and KDR levels in the vitreous of diabetic rats were related to the early retinopathy induced by diabetes.

OBJETIVO: Investigar el nivel vítreo del factor de crecimiento endotelial vascular (FCEV) y receptor con dominio inserto-quinasa (KDR) en ratas diabéticas, y explorar el papel de FCEV y KDR en la retinopatía diabética. MÉTODOS: Ochenta y cuatro ratas adultas Wistar fueron divididas aleatoriamente en dos grupos. A cincuenta y ocho ratas en el grupo A se les inyectó estreptozotocinapor vía intraperitonealpara inducir diabetes, mientras que a 20 ratas en el grupo B se les inyectó una solución salina fisiológica. Se usó un medidor de glucosa en sangre para detectar el nivel de glucosa en sangre a las 72 horas después de la inyección. Un nivel de glucosa en sangre > 16.67 mmol/L se consideró como un modelo exitoso. Se analizó el nivel de glucosa en sangre, y se midió la masa corporal en el mismo día del modelado, y una semana, dos semanas, y cuatro semanas después del modelado. Cuatro semanas después del modelado, se tomó el humor vítreo, y los niveles de FCEV y KDR fueron detectados mediante ensayo por inmunoabsorción ligado a enzimas (ELISA). Los globos oculares fueron fijados con para formaldehido e incrustados por petrolin para tinción (H & E) hematoxilina-eosina. RESULTADOS: Cuarenta y dos ratas sobrevivieron y 16 ratas murieron en el grupo A. Ninguna de las ratas en el grupo B murió. La glucosa en la sangre a la semana, las dos semanas, y las cuatro semanas entre los dos grupos tuvo diferencias estadísticas (p < 0.05). El peso a la semana y a las dos semanas entre los dos grupos no fue diferente, pero hubo diferencia estadística a las cuatro semanas entre los dos grupos (p < 0.01). Los resultados de ELISA mostraron que los niveles de FCEV y KDR fueron 0.276 ± 0.026 ng/mLy 2.936 ± 0.295 ng/mL en el grupo A, 0.231 ± 0.021 ng/mL y 2.394 ± 0.227 ng/mL en el grupo B, respectivamente. Los niveles de FCEV y KDR del grupo A fueron superiores a los del grupo B (p < 0.05). CONCLUSIONES: Los cambios de nivel FCEV y KDR en el humor vítreo de las ratas diabéticas estaban asociados con la retinopatía temprana inducida por diabetes.

Protein expression of VEGF, IGF-1 and FGF in retroocular connective tissues and clinical correlation in Graves' ophthalmopathy / Expressão protéica de VEGF, IGF-1 e FGF no tecido conjuntivo retro-ocular e correlação clínica na oftalmopatia de Graves

PURPOSE: To investigate the immunohistochemical expression (IGF-1, EGFr, EGF, c-erbB-2/HER-2/neu, PDGF-A, PDGF-B, FGF and VEGF) in patients with Graves' ophthalmopathy. METHODS: Twenty-four samples (Graves' ophthalmopathy patients) underwent lateral rectus muscle and surrounding fibrous and adipose tissue biopsy. The control group was obtained by strabismus surgery. Correlation between clinical- ophthalmologic, endocrinological, ultrasonographic findings, and immunohistochemical expression was performed. RESULTS: IGF-1: There were 7 positive cases (29.2 percent). There was a direct relation with higher CAS (clinical activity score) in all of them and if only CAS equal or higher than 5 was considered, this was 54.5 percent. FGF: There was expression in 5 cases (20.8 percent) with a direct relation in all those with higher CAS (>5) (45.4 percent). VEGF: There were two positive cases (8.3 percent) for VEGF in endothelial cells, in these cases the patients also presented CAS higher than 5. There was no expressions of all growth factors in the control group. CONCLUSIONS: All patients, except one, with positive expression of FGF, IGF-1 and VEGF showed CAS greater than 5, suggesting in this way an important role of these growth factors in the pathogenesis and severity of Graves' ophthalmopathy. However, statistical analysis revealed only significant association between IGF-1 and male sex (P=0.034). Low ultrasound reflectivity and endocrine status may not correlate directly with disease activity or with immunoexpression of growth factors and c-erbB-2/HER-2/neu.

OBJETIVO: Investigar a expressão imuno-histoquímica de IGF-1, EGFr, EGF, c-erbB-2/HER-2/neu, PDGF-A, PDGF-B, FGF e VEGF na oftalmopatia de Graves. MÉTODOS: Vinte e dois pacientes (oftalmopatia de Graves) foram submetidos à biópsia do músculo reto lateral e tecido fibroso e adiposo adjacente. O grupo controle foi de pacientes de cirurgia de estrabismo. Foi feita correlação entre achados clínico-oftalmológicos, endocrinológicos, ultra-sonográficos e da expressão imuno-histoquímica dos fatores de crescimento. RESULTADOS: IGF-1: Houve 7 casos positivos (29,2 por cento). Houve correlação direta com o CAS (clinical activity score) elevado em todos os casos e em que consideramos CAS apenas acima de 5, em 54,5 por cento. FGF: Houve expressão em 5 casos (20,8 por cento) com relação direta com CAS elevado em todos os casos e em que consideramos CAS maior que 5 (45,4 por cento). VEGF: Houve dois casos positivos (8,3 por cento) para VEGF nas células endoteliais e estes casos também apresentavam CAS maior que 5. A imunorreatividade foi negativa em todo grupo controle. CONCLUSÃO: Todos os pacientes, com exceção de um, com expressão positiva para FGF, IGF-1 e VEGF mostraram CAS maior que 5, sugerindo importante papel destes fatores de crescimento na patogênese e gravidade da oftalmopatia de Graves. Entretanto, a análise estatística demonstrou associação significativa entre IGF-1 e o sexo masculino (P=0,034). Baixa refletividade ao ultra-som e condição endócrina não estiveram correlacionadas.

Vascular endothelial growth factor as an indicator of severity of diabetic retinopathy

To evaluate vascular endothelial growth factor [VEGF] as an indicator of severity in diabetic retinopathy. The study included 120 patients divided equally into 3 groups [proliferative diabetic retinopathy [PDR] group, non proliferative diabetic retinopathy [NPDR] group and non diabetics control group]. Vitreous and blood samples were collected from all patients. VEGF concentrations were determined using enzyme linked immuno-sorbent assay and correlated with retinopathy grading. Vitreous concentrations were statistically significant higher than serum concentrations in both retinopathy groups with strong positive correlation [r = 0.927 at p < 0.001 in PDR and r = 0.646 at p < 0.001 in NPDR]. Serum and vitreous VEGF concentrations in diabetics were statistically significant higher than control group [p<0.01]. Both increased with the progression of retinopathy. Very mild NPDR patients had the lowest vitreous concentration [mean = 20.33 ng / ml] but still higher than controls [mean = 4.53 ng / ml]. PDR patients with tractional detachment had the highest vitreous concentration [mean = 225.18 ng / ml]. VEGF concentrations were statistically significant higher in NPDR patients with maculopathy than NPDR patients without maculopathy. There is a strong direct positive correlation between VEGF concentrations and retinopathy grading