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1.
Electromagn Biol Med ; 43(1-2): 46-60, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38329038

RESUMO

This study aimed to assess PEMF in a rat model of senile osteoporosis and its relationship with NLRP3-mediated low-grade inflammation in the bone marrow microenvironment. A total of 24 Sprague Dawley (SD) rats were included in this study. Sixteen of them were 24-month natural-aged male SD rats, which were randomly distributed into the Aged group and the PEMF group (n = 8 per group). The remaining 8 3-month -old rats were used as the Young positive control group (n = 8). Rats in the PEMF group received 12 weeks of PEMF with 40 min/day, five days per week, while the other rats received placebo PEMF intervention. Bone mineral density/microarchitecture, serum levels of CTX-1 and P1CP, and NLRP3-related signaling genes and proteins in rat bone marrow were then analyzed. The 12-week of PEMF showed significant mitigation of aging-induced bone loss and bone microarchitecture deterioration, i.e. PEMF increased the bone mineral density of the proximal femur and L5 vertebral body and improved parameters of the proximal tibia and L4 vertebral body. Further analysis showed that PEMF reversed aging-induced bone turnover, specifically, decreased serum CTX-1 and elevated serum P1CP. Furthermore, PEMF also dramatically inhibited NLRP3-mediated low-grade inflammation in the bone marrow, i.e. PEMF inhibited the levels of NLRP3, proCaspase1, cleaved Caspase1, IL-1ß, and GSDMD-N. The study demonstrated that PEMF could mitigate the aging-induced bone loss and reverses the deterioration of bone microarchitecture probably through inhibiting NLRP3-mediated low-grade chronic inflammation to improve the inflammatory bone microenvironment in aged rats.


Assuntos
Densidade Óssea , Campos Eletromagnéticos , Inflamação , Proteína 3 que Contém Domínio de Pirina da Família NLR , Osteoporose , Ratos Sprague-Dawley , Animais , Osteoporose/terapia , Osteoporose/prevenção & controle , Osteoporose/sangue , Osteoporose/metabolismo , Osteoporose/patologia , Masculino , Ratos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamação/terapia , Densidade Óssea/efeitos da radiação , Medula Óssea/efeitos da radiação , Medula Óssea/metabolismo , Microambiente Celular , Envelhecimento
3.
Int J Radiat Oncol Biol Phys ; 114(3): 463-471, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35870710

RESUMO

PURPOSE: Pelvic irradiation leads to substantial dose to the pelvic girdle. However, bone density loss as a function of radiation therapy dose and time has not been investigated. This study was undertaken to evaluate such a dose-response relationship. METHODS AND MATERIALS: Women undergoing pelvic radiation therapy for cervix cancer within a phase 3 trial were included. The study necessitated 2 computed tomography imaging sets acquired at least 12 months apart in patients with no evidence of relapse. All images were transferred to the treatment planning system to determine radiation dose and Hounsfield unit (HU). Across the entire lumbopelvic region (lumbar 1-5 [L1-5] vertebrae, pubic symphysis, femur, acetabulum, greater trochanter, and anterior-superior iliac spine) multiple regions were defined to measure radiation therapy dose and HU. Bone health was categorized as normal if >130 HU, osteopenic at 110 to 130 HU, and osteoporotic <110 HU at baseline and follow-up. Univariate analysis was performed to test the effect of various factors on HU. Further interaction among radiation therapy dose, time, and HU was assessed using a linear mixed model. RESULTS: Overall, 132 of 300 patients were eligible. The median age was 49 (42-56) years. With a prescription dose of 50 Gy, the L1 and L2 vertebrae received a median dose of 1.2 and 4 Gy, respectively, and L3-5 received 10 to 50 Gy. At 24 months, median HU loss at L4-5 was 45 HU (interquartile range, 34-77 HU). Out of the 132 patients, at baseline 96% had normal bone health. However, at the last follow-up, 3% of patients had normal bone health, 12% developed osteopenia, and 85% developed osteoporosis (P < .001). There were no patient- or treatment-related factors predicted for HU loss on univariate analysis. HU loss >60 to 70 was observed at >45 Gy at L5 vertebra (60-70 HU, P < .02) and >15 Gy at L4 vertebra (33 HU; P = .04). CONCLUSIONS: Dose-response relationship is observed between radiation dose and bone mineral density loss. Prospective studies are needed to corroborate these observations and design future interventions.


Assuntos
Densidade Óssea , Osteoporose , Absorciometria de Fóton/métodos , Densidade Óssea/efeitos da radiação , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos
4.
Cancer Radiother ; 26(1-2): 368-376, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34955420

RESUMO

We present the update of the recommendations of the French society of oncological radiotherapy on bone metastases. This is a common treatment in the management of patients with cancer. It is a relatively simple treatment with proven efficacy in reducing pain or managing spinal cord compression. More complex treatments by stereotaxis can be proposed for oligometastatic patients or in case of reirradiation. In this context, increased vigilance should be given to the risks to the spinal cord.


Assuntos
Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Densidade Óssea/efeitos da radiação , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Dor do Câncer/radioterapia , França , Humanos , Órgãos em Risco/diagnóstico por imagem , Cuidados Pós-Operatórios , Radioterapia (Especialidade) , Radioterapia Conformacional/métodos , Radioterapia Guiada por Imagem/métodos , Reirradiação , Compressão da Medula Espinal/radioterapia , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/radioterapia , Carga Tumoral
5.
Gynecol Oncol ; 160(2): 619-624, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33309416

RESUMO

Cancer treatment-induced bone loss is a known side effect of cancer therapy that increases the risk of osteoporosis and bone fracture. Women with gynecologic cancer are at increased risk of bone loss secondary to the combined effect of oophorectomy and adjuvant therapies. Data regarding bone loss in women with gynecologic cancers are overall lacking compared to other cancer populations. Consequently, guidelines for osteoporosis screening in women with cancer are largely based on data generated among non-gynecologic cancer survivors. This article reviews current available data of bone health in women with gynecologic cancer, summarizes best-available guidelines for screening for osteoporosis in women with cancer, and provides guidance for osteoporosis screening in women with gynecologic cancers based on best available evidence.


Assuntos
Densidade Óssea/fisiologia , Sobreviventes de Câncer/estatística & dados numéricos , Neoplasias dos Genitais Femininos/terapia , Programas de Rastreamento/normas , Osteoporose/diagnóstico , Absorciometria de Fóton , Antineoplásicos Hormonais/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/efeitos da radiação , Quimioterapia Adjuvante/efeitos adversos , Quimioterapia Adjuvante/métodos , Medicina Baseada em Evidências/normas , Feminino , Neoplasias dos Genitais Femininos/complicações , Neoplasias dos Genitais Femininos/mortalidade , Humanos , Menopausa/efeitos dos fármacos , Menopausa/metabolismo , Menopausa/efeitos da radiação , Osteoporose/epidemiologia , Osteoporose/etiologia , Osteoporose/metabolismo , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/efeitos da radiação , Ovário/cirurgia , Guias de Prática Clínica como Assunto , Radioterapia Adjuvante/efeitos adversos , Fatores de Risco , Salpingo-Ooforectomia/efeitos adversos , Sobrevivência
6.
Electromagn Biol Med ; 40(1): 26-32, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33251878

RESUMO

This study aimed to investigate the therapeutic effect of pulsed electromagnetic field (PEMF) on bone wound in rats as a potential therapy for bone fracture-related conditions. Male rats, aged 3 months, were used to construct model of bone wounding. Wound models were randomly selected to receive PEMF therapy at 1 to 10 mT intensity. Models that did not receive PEMF therapy were used as control. The serum concentrations of calcium (Ca), phosphorus (P) and alkaline phosphatase (ALP) were determined. Bone density and biomechanical properties of callus were measured using a tensile tester. Compared with control, rats subjected to PEMF therapy had similar weight gain, but significantly higher levels of serum Ca and ALP (P < .05) at 5 and 10 mT, while the serum level of P remained unchanged after PEMF therapy. The bone mineral density of callus increased after the therapy, particularly, after 5 and 10 mT therapy (P < .05). Biomechanical measurements showed that 21 days after the therapy, the maximum load, fracture load, elastic load and bending energy were significantly greater in rats receiving 5 and 10 mT PEMF therapy as compared with control (P < .05). Our experiments demonstrate that PEMF at 5 and 10 mT can significantly accelerate wound healing and enhance the repairing ability of bone tissue.


Assuntos
Osso e Ossos/fisiologia , Osso e Ossos/efeitos da radiação , Campos Eletromagnéticos , Cicatrização/efeitos da radiação , Fosfatase Alcalina/metabolismo , Animais , Fenômenos Biomecânicos/efeitos da radiação , Densidade Óssea/efeitos da radiação , Cálcio/metabolismo , Fósforo/metabolismo , Ratos
7.
RFO UPF ; 25(3): 378-383, 20201231. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-1357817

RESUMO

Objetivo: relatar um caso de aumento da hiperdensidade da cortical óssea línguo-basal pós-radioterapia em região de cabeça e pescoço por meio de avaliação imaginológica. Relato de caso: paciente do sexo feminino, 80 anos, procurou tratamento odontológico com a finalidade de reabilitação oral com implantes dentários. Na anamnese, relatou histórico de carcinoma espinocelular em regiões distintas da cavidade oral. No exame clínico, notou-se que a paciente era edêntula total e foi solicitado um exame de tomografia computadorizada de feixe cônico. Foi observado, na região anterior inferior, aumento da hiperdensidade da cortical óssea línguo-basal, com osso compacto mais espesso, achado incomum na literatura após radioterapia. Considerações finais: os efeitos da radioterapia em mandíbula estão relatados na literatura. No caso clínico em questão, detectou-se uma alteração pouco notada em pacientes submetidos à radioterapia, fazendo surgir novos questionamentos, sendo eles sobre o diagnóstico dessa modificação na estrutura óssea e suas repercussões. (AU)


Objective: to report a case of increased hyperdensity of the lingual-basal bone cortex after radiotherapy in the head and neck region by means of imaging evaluation. Case report: female patient, 80 years old, sought dental treatment for the purpose of oral rehabilitation with dental implants. In the anamnesis, she reported a history of squamous cell carcinoma in different regions of the oral cavity. Upon clinical examination, it was noted that the patient was total edentulous and a cone beam computed tomography examination was requested. An increase in the hyperdensity of the lingual-basal bone cortex was observed in the lower anterior region, with thicker compact bone, an unusual finding in the literature after radiotherapy. Final considerations: the effects of radiotherapy on the mandible are reported in the literature. In the clinical case in question, a little-noticed change was detected in patients undergoing radiotherapy, leading to new questions, concerning the diagnosis of this change in bone structure and its repercussions.(AU)


Assuntos
Humanos , Feminino , Idoso de 80 Anos ou mais , Lesões por Radiação/complicações , Densidade Óssea/efeitos da radiação , Osso Cortical/efeitos da radiação , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Mandíbula/efeitos da radiação , Tomografia Computadorizada de Feixe Cônico , Mandíbula/diagnóstico por imagem
8.
Res Vet Sci ; 133: 226-231, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33032109

RESUMO

As bone healing is altered after external radiation therapy, its evaluation is mandatory and lacks in clinical practice. The aim of the pilot study was to validate micro computed tomography (microCT) as a simple and reliable technique for assessing irradiated bone healing in the rabbit's mandible and compare with histologic findings. Nineteen rabbits (female New Zealand white) were used. The radiation protocol consisted of 5 sessions delivering 8.5 Gy each. MicroCT was performed at D0, D7, D14, D28 and D42 for the control group and D0, D28 and D42 for the irradiated group. A modified Perry's score was determined on histologic samples, and comparison between microCT and histological findings was performed. The main differences between irradiated and non-irradiated rabbits were observed at Day 28 and 42. There was a strong correlation between imaging and histologic findings. Radiation decreases bone quality and bone mineral density. As the correlation was strong between microCT and histologic findings, micro imaging could be considered as a simple and reliable technique to assess bone healing after radiation therapy and allows an easy comparison between samples, without invasive procedures. Great attention should be kept on the parameters and on the region of interest. The development of in-vivo microCT enlarges the perspectives of microCT use in experimental studies, avoiding invasive procedures, and preserving animal lives and well-being, and furthermore lead to clinical applications.


Assuntos
Doenças Ósseas/veterinária , Mandíbula/efeitos da radiação , Cicatrização , Microtomografia por Raio-X , Animais , Densidade Óssea/efeitos da radiação , Feminino , Mandíbula/cirurgia , Projetos Piloto , Coelhos , Radioterapia/veterinária , Microtomografia por Raio-X/métodos
9.
PLoS One ; 15(9): e0238127, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32960898

RESUMO

PURPOSE: The aim of this study was to assess the determinants of bone health in the group of women over 40 years old. Lifestyle factors such as past and present physical activity, past and present sun exposure, current dietary intake of calcium and vitamin D, nutritional status as measured by BMI, family history of osteoporosis and current hormonal status were analysed. METHODS: The study involved 500 women over 40 years old. All examined women was the same ethnicity- European origin. Methods used: densitometry method (DXA), bioelectrical impedance analysis, International Physical Activity Questionnaire, nutrition questionnaire, past and present sun exposure questionnaire. Past and present physical activity, past and present sun exposure and sufficient level of calcium in the diet proved to be the most important factors determining mineralization of bone tissue of women. In order to indicate an independent association of the correct bone tissue mineralization with individual factors, multivariate analysis was used-logistic regression. RESULTS: The norm BMD in the distal part of the forearm was strongly influenced: recommended dietary calcium intake (OR = 5.95; p = 0.003), moderately (OR = 1.88; p = 0.053) and high (OR = 14.0; p<0.001) past physical activity, sufficient (OR = 4.97; p<0.001) and high (OR = 18.9; p = 0.004) level of present physical activity, sufficient past (OR = 5.15; p<0.001) and sufficient present sun exposure (OR = 10.0; p<0.001). The chance for the BMD prox norm was also increased several times: high past physical activity (OR = 68.4; p<0.0001) and sufficient past sun exposure (OR = 10.6; p<0.001), moderate past activity (OR = 4.20; p<0.001), sufficient (OR = 6.13; p<0.001) and high (OR = 10.0; p<0.001) present physical activity, sufficient present sun exposure (OR = 9.09; p<0.0001), recommended intake of calcium (OR = 9.57; p<0.001) and vitamin D (OR = 2.68; p = 0.052). Whereas e significantly lower likelihood for the BMD prox norm was found in women with the oldest hormonal status (postmenopausal period) (OR = 0.18; p<0.001), with osteoporosis in the family (OR = 0.37; p<0.001) and living in an agglomeration (OR = 0.68; p = 0.03). CONCLUSION: Interventions to increase physical activity, especially outdoors, may help reduce risk of osteoporosis, fractures and subsequent healthcare costs.


Assuntos
Densidade Óssea/fisiologia , Densidade Óssea/efeitos da radiação , Exercício Físico , Estado Nutricional , Exposição à Radiação/análise , Luz Solar , Índice de Massa Corporal , Densidade Óssea/efeitos dos fármacos , Cálcio/farmacologia , Suplementos Nutricionais , Feminino , Humanos , Estilo de Vida , Modelos Logísticos , Anamnese , Pessoa de Meia-Idade , Polônia , Vitamina D/farmacologia
10.
Sci Rep ; 10(1): 6484, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32300161

RESUMO

Spaceflight is a unique environment that includes at least two factors which can negatively impact skeletal health: microgravity and ionizing radiation. We have previously shown that a diet supplemented with dried plum powder (DP) prevented radiation-induced bone loss in mice. In this study, we investigated the capacity of the DP diet to prevent bone loss in mice following exposure to simulated spaceflight, combining microgravity (by hindlimb unloading) and radiation exposure. The DP diet was effective at preventing most decrements in bone micro-architectural and mechanical properties due to hindlimb unloading alone and simulated spaceflight. Furthermore, we show that the DP diet can protect osteoprogenitors from impairments resulting from simulated microgravity. Based on our findings, a dietary supplementation with DP could be an effective countermeasure against the skeletal deficits observed in astronauts during spaceflight.


Assuntos
Doenças Ósseas Metabólicas/prevenção & controle , Radiação Cósmica/efeitos adversos , Elevação dos Membros Posteriores/efeitos adversos , Prunus domestica , Voo Espacial , Animais , Densidade Óssea/fisiologia , Densidade Óssea/efeitos da radiação , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/fisiopatologia , Modelos Animais de Doenças , Alimentos em Conserva , Elevação dos Membros Posteriores/fisiologia , Humanos , Masculino , Camundongos , Esqueleto/diagnóstico por imagem , Esqueleto/fisiopatologia , Esqueleto/efeitos da radiação , Microtomografia por Raio-X
11.
J Clin Densitom ; 23(1): 21-28, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30655188

RESUMO

INTRODUCTION/BACKGROUND: The present study was carried out to determine prevalence of vitamin D deficiency and related factors in individuals living in nursing home and their own homes. METHODOLOGY: This cross-sectional study included 72 elderly people 60 yr and older. All subjects were given a questionnaire form evaluating their individual characteristics, eating habits which affected their vitamin D status, wearing habits, and their duration of sun exposure and a Standardized Mini Mental Test evaluating their cognitive levels. Serum 25(OH)D, calcium, parathyroid hormone, alkaline phosphatase and phosphorus levels, and bone mineral density measurements were also considered. RESULTS: Vitamin D deficiency was observed in 47% of elderly people (nursing home: 64%, own home 31%, p = 0.05). Both 25(OH)D (14 ± 8 vs 27 ± 10, respectively, p < 0.001) and ultraviolet index value (0.63 ± 0.3 vs 0.92 ± 0.27, respectively, p < 0.001) were lower in people living in nursing home compared to ones living in their own homes. Parathyroid hormone level, on the other hand, was lower in people living in own homes. Vitamin D deficiency/insufficiency was more common in elderly people living in nursing home (100%) compared to those living in their own homes (64%) (p = 0.003). Osteopenia and osteoporosis incidence rates were also higher in elderly people living in nursing home (p = 0.001). No significant associations were found between vitamin D status and body mass index, smoking or dietary habits (p > 0.05). As levels of benefiting from ultraviolet index increased, significantly improvements were observed in 25(OH)D levels (p < 0.001). CONCLUSIONS: In elderly people living in nursing home, vitamin D deficiency was higher and benefitting from ultraviolet index was lower compared to elderly people living in their own homes. Vitamin D deficiency could be prevented in elderly people, especially ones living in nursing homes, through enough sun exposure with appropriate clothing.


Assuntos
Vida Independente/estatística & dados numéricos , Casas de Saúde/estatística & dados numéricos , Luz Solar , Vitamina D/sangue , Idoso , Fosfatase Alcalina/sangue , Índice de Massa Corporal , Densidade Óssea/efeitos da radiação , Cálcio/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Testes de Estado Mental e Demência , Hormônio Paratireóideo/sangue , Fósforo/sangue , Fatores de Risco , Fatores Sexuais , Deficiência de Vitamina D/epidemiologia
12.
Calcif Tissue Int ; 106(2): 180-193, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31583426

RESUMO

Radiation therapy and estrogen deficiency can damage healthy bone and lead to an increased fracture risk. The goal of this study is to develop a mouse model for radiation therapy using a fractionated biologically equivalent dose for cervical cancer treatment in both pre- and postmenopausal women. Thirty-two female C57BL/6 mice 13 weeks of age were divided into four groups: Sham + non-irradiated (SHAM + NR), Sham + irradiated (SHAM + IRR), ovariectomy + non-irradiated (OVX + NR) and ovariectomy + irradiated (OVX + IRR). The irradiated mice received a 6 Gy dose of X-rays to the hindlimbs at Day 2, Day 4 and Day 7 (18 Gy total). Tissues were collected at Day 35. DEXA, microCT analysis and FEA were used to quantify structural and functional changes at the proximal tibia, midshaft femur, proximal femur and L1 vertebra. There was a significant (p < 0.05) decline in proximal tibia trabecular BV/TV from (1) IRR compared to NR mice within Sham (- 46%) and OVX (- 41%); (2) OVX versus Sham within NR mice (- 36%) and IRR mice (- 30%). With homogenous material properties applied to the proximal tibia mesh using FEA, there was (1) an increase in whole bone (trabecular + cortical) structural stiffness from IRR compared to NR mice within Sham (+ 10%) and OVX (+ 15%); (2) a decrease in stiffness from OVX versus Sham within NR mice (- 18%) and IRR mice (- 14%). Fractionated irradiation and ovariectomy both had a negative effect on skeletal microarchitecture. Ovariectomy had a systemic effect, while skeletal radiation damage was largely specific to trabecular bone within the X-ray field.


Assuntos
Osso e Ossos/fisiologia , Estradiol/deficiência , Lesões Experimentais por Radiação , Animais , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/efeitos da radiação , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/efeitos da radiação , Modelos Animais de Doenças , Estradiol/sangue , Estradiol/farmacologia , Feminino , Fêmur/efeitos dos fármacos , Fêmur/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia , Lesões Experimentais por Radiação/complicações , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/fisiopatologia , Radiografia , Radioterapia/efeitos adversos , Dosagem Radioterapêutica , Tíbia/efeitos dos fármacos , Tíbia/efeitos da radiação , Microtomografia por Raio-X
13.
Rev. esp. cir. oral maxilofac ; 41(4): 160-166, oct.-dic. 2019. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-191800

RESUMO

INTRODUCCIÓN: El colgajo peroneo es actualmente una de las técnicas más elegidas para la reconstrucción de defectos mandibulares. Muchos de los pacientes reconstruidos con este colgajo presentan patología oncológica que precisa tratamiento adyuvante con radioterapia. Los efectos adversos de la radioterapia sobre los tejidos son conocidos, pudiendo desembocar en osteorradionecrosis. El objetivo de este estudio es el análisis de la densidad ósea de los colgajos peroneos en los pacientes que han recibido radioterapia frente a los que no, y su posible correlación con las complicaciones posteriores. MATERIAL Y MÉTODOS: Realizamos un estudio retrospectivo de los colgajos peroneos realizados por nuestro servicio desde enero de 2011 hasta diciembre de 2016. Los criterios de inclusión de los pacientes fue el haber sido reconstruidos con un colgajo peroneo y disponer de un TC de control a los tres meses postradioterapia en caso de haberla precisado. Se recogió la edad, densidad ósea peronea, desviación estándar cuerpo mandibular remanente y colgajo peroneo, así como las complicaciones postoperatorias. Los datos extraídos fueron analizados a través del Software SAS (Statistical Analisys System). RESULTADOS: En total se recogieron 61 pacientes, siendo la media de edad de 54,46 años. De estos 61 pacientes se excluyeron 11 al no presentar TC de control, de los 50 pacientes restantes, 27 recibieron tratamiento radioterápico adyuvante (54 %) mientras 23 no la recibieron (46 %). En los pacientes irradiados un alto porcentaje (84,62 %) recibieron altas dosis de radioterapia (> 60 Gy). Se encontraron diferencias estadísticamente significativas (p < 0,05) respecto a la edad y la desviación estándar de la densidad ósea del cuerpo mandibular remanente, mientras que en el resto de los parámetros no se encontraron diferencias estadísticamente significativas. Los pacientes irradiados presentaron un mayor porcentaje de complicaciones frente a los pacientes no irradiados sin diferencias estadísticamente significativas. DISCUSIÓN Las nuevas técnicas de radioterapia de intensidad modulada permiten una dosis relativamente uniforme en un objetivo, evitando altas dosis en los tejidos circuncidantes. A pesar del avance en las técnicas de radioterapia, actualmente en la mayoría de centros se continúa realizando un tratamiento completo del volumen del lecho tumoral, que incluye en el campo de irradiación el colgajo con el que se reconstruye. Los casos de osteonecrosis mandibular que se presentaron fueron en pacientes irradiados y a nivel del cuerpo mandibular remanente. La densidad ósea a nivel del colgajo peroneo sí que presentó diferencias estadísticamente significativas en pacientes irradiados frente a no irradiados; este aspecto puede influir en el índice de complicaciones. CONCLUSIONES: Consideramos con los resultados del estudio, plantear nuevos estudios prospectivos para valorar la necesidad de irradiar el tejido óseo del colgajo peroneo como parte del volumen del lecho tumoral, siendo que este tejido no ha estado en contacto con el tumor primario, ante el mayor índice de complicaciones asociados a la radioterapia en estos tejidos


INTRODUCTION: The fibular flap is currently one of the most chosen techniques for the reconstruction of mandibular defects. Many of the patients reconstructed with this flap present oncological pathology that requires adjuvant treatment with radiotherapy. The adverse effects of radiotherapy on tissues are known, and can lead to Osteorradionecrosis. The aim of this study is to analyze the bone density of peroneal flaps in patients who have received radiotherapy against those who do not and their possible correlation with subsequent complications. MATERIAL AND METHODS: We designed a retrospective study of the fibular flaps performed by our service from January 2011 to December 2016. The criteria for inclusion of patients was to have been reconstructed with a peroneal flap and have a control CT at 3 months after radiotherapy. Age, bone density, standard deviation and further complications were extracted. The extracted data was analyzed through the SAS (statistical Analisys System) Software. RESULTS: 61 patients were collected; the mean age was of 54.46 years. Of these 61 patients were excluded 11 by not presenting control TC, of the 50 patients remaining, 27 received adjuvant radiotherapy treatment (54 %) while 23 did not receive (46 %). In irradiated patients a high percentage (84.62 %) received high doses of radiotherapy (> 60 Gy). Statistically significant differences were found (p < 0.05) with respect to age and standard deviation of bone density of the remaining mandibular body, while in the rest of the parameters no statistical significant differences were found. Irradiated patients presented a higher percentage of complications compared to non-irradiated patients without statistically significant differences. DISCUSSION: The new techniques of intensity-modulated radiotherapy allow a relatively uniform dose in a target, avoiding high doses in the circumcising tissues. Despite the progress in radiotherapy techniques, currently in most centers, it continues to perform a complete treatment of the volume of the tumor bed that includes in the field of irradiation the flap with which it is reconstructed. The cases of mandibular osteonecrosis that were presented were in irradiated patients and in the remaining mandible. Bone density at the level of the fibular flap showed statistically significant differences in irradiated patients compared to non-irradiated, this aspect may influence in the index of complications. CONCLUSIONS: We consider to propose new prospective studies to assess the need to irradiate the bone tissue of the fibular flap as part of the volume of the tumor bed, knowing that this tissue has not been in contact with the primary tumor, and the high index of complications associated with radiotherapy


Assuntos
Humanos , Fíbula/efeitos da radiação , Retalhos Cirúrgicos , Densidade Óssea/efeitos da radiação , Osteorradionecrose/diagnóstico , Reconstrução Mandibular/métodos , Estudos Retrospectivos , Fíbula/transplante , Neoplasias Mandibulares/cirurgia
14.
Int J Mol Med ; 44(6): 2265-2275, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31638191

RESUMO

Radiotherapy, one of the clinical treatments of cancer, is accompanied by a high risk of damage to healthy tissues, such as bone loss and increased risk of fractures. The aim of the present study was to establish a rat model of local and systemic bone injury by focal irradiation, in order to study the etiological mechanism and intervention. The proximal metaphyseal region of the left hindlimb of male Sprague­Dawley rats were exposed to a single 2 Gy or three 8 Gy doses delivered on days 1, 3 and 5 using a small animal irradiator, the changes in bone volume and microarchitecture were evaluated, and the mineral apposition rate (MAR) was assessed. Furthermore, bone marrow­derived macrophages (BMMs) were isolated and induced to osteoclasts. It has been demonstrated that a single dose of 2 Gy may result in a significant loss of lumbar bone density at 3 days post­irradiation, however this is restored at 30 days post­irradiation. In the 3x8 Gy irradiation rat model, there was a rapid decrease in the aBMD of lumbar spine at 3 days and at 7 days post­irradiation, and the aBMD decline persisted even at 60 days post­irradiation. In addition, microCT analysis revealed a persistent decline in bone volume and damage in microarchitecture in the 3x8 Gy irradiation model, accompanied by a decrease in MAR, index of the decline in bone­forming ability. In the cellular mechanism, a single 2 Gy local irradiation mainly manifested as an enhancement of the BMMs osteoclastogenesis potential, which was different from the osteoclastogenesis inhibition after high­dose focal irradiation (3x8 Gy). In summary, the irradiation with simulated clinical focal fractionated radiotherapy exerts short­ and long­term systemic injury on bone tissue, characterized by different osteoclastogenesis potential between the high dose mode and a single 2 Gy focal irradiation. Physicians must consider the irreversibility of bone damage in clinical radiotherapy.


Assuntos
Densidade Óssea/efeitos da radiação , Reabsorção Óssea/genética , Osso e Ossos/metabolismo , Osteoclastos/efeitos da radiação , Animais , Densidade Óssea/genética , Reabsorção Óssea/patologia , Osso e Ossos/lesões , Osso e Ossos/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Exposição à Radiação , Ratos , Ratos Sprague-Dawley , Microtomografia por Raio-X
15.
Bone ; 128: 115043, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31445224

RESUMO

Bone can become brittle when exposed to ionizing radiation across a wide range of clinically relevant doses that span from radiotherapy (accumulative 50 Gy) to sterilization (~35,000 Gy). While irradiation-induced embrittlement has been attributed to changes in the collagen molecular structure, the relative role of collagen fragmentation versus non-enzymatic collagen crosslinking remains unclear. To better understand the effects of radiation on the bone material without cellular activity, we conducted an ex vivo x-ray radiation experiment on excised mouse lumbar vertebrae. Spinal tissue from twenty-week old, female, C57BL/6J mice were randomly assigned to a single x-ray radiation dose of either 0 (control), 50, 1000, 17,000, or 35,000 Gy. Measurements were made for collagen fragmentation, non-enzymatic collagen crosslinking, and both monotonic and cyclic-loading compressive mechanical properties. We found that the group differences for mechanical properties were more consistent with those for collagen fragmentation than for non-enzymatic collagen crosslinking. Monotonic strength at 17,000 and 35,000 Gy was lower than that of the control by 50% and 73% respectively, (p < 0.001) but at 50 and 1000 Gy was not different than the control. Consistent with those trends, collagen fragmentation only occurred at 17,000 and 35,000 Gy. By contrast, non-enzymatic collagen crosslinking was greater than control for all radiation doses (p < 0.001). All results were consistent both for monotonic and cyclic loading conditions. We conclude that the reductions in bone compressive monotonic strength and fatigue life due to ex vivo ionizing radiation are more likely caused by fragmentation of the collagen backbone than any increases in non-enzymatic collagen crosslinks.


Assuntos
Densidade Óssea/efeitos da radiação , Osso e Ossos/metabolismo , Colágeno/metabolismo , Radiação Ionizante , Animais , Força Compressiva/efeitos da radiação , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Estresse Mecânico , Microtomografia por Raio-X
16.
J Photochem Photobiol B ; 197: 111504, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31228687

RESUMO

High disappointment rate of the ligament to hard tissue mending after the medical procedure has dependably been a testing issue in rotator cuff repair. Considering the elasticity of carbon dot decorated polyethylene (f-CDs-PE) and osteogenic movement of gold substituted hydroxyapatite (Au@HA) bioceramic, f-CDs-PE-Au@HA biocomposite coatings were created by an electrophoretic deposition method (EPD), the in vivo and in vitro bioactivity and cytocompatibility were researched. The physico-chemical properties of f-CDs-PE-Au@HA biocomposite coatings were characterized using fourier transform infra-red (FTIR) and X-Ray diffractometery (XRD). The morphology of the fabricated biocomposites was analyses via scanning electron microscopy (SEM) and transmission electron microscopy (TEM) methods. With a gamma-irradiation of f-CDs-PE-Au@HA biocomposite coating (BC2), the bond and multiplication of cells on biocomposite coating were improved. The specimen with a f-CDs-PE-Au@HA biocomposite (BC2) demonstrated a most noteworthy alkaline phosphatase activity articulation. The animal model consequences additionally show that the f-CDs-PE-Au@HA biocomposite (BC2) had great bioactive and cytocompatibility, which could develop the association of collagen and the arrangement of ligament and hard tissue. Expansion of the gamma-ray irradiation with f-CDs-PE-Au@HA biocomposite coating (BC2) at the tendon- hard tissue crossing point was exhibited to reinforce the mending entheses, increment hard tissue and tendon development and progress collagen association contrasted and control. The above outcomes have recommended that the progressive, implantable and solid stringy platforms built utilizing EPD extraordinary potential for enlargement of rotator cuff tears-recuperating.


Assuntos
Materiais Revestidos Biocompatíveis/química , Durapatita/química , Raios gama , Pontos Quânticos/química , Articulação do Ombro/patologia , Titânio/química , Artroplastia de Substituição , Densidade Óssea/efeitos da radiação , Carbono/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Materiais Revestidos Biocompatíveis/farmacologia , Colágeno Tipo I/metabolismo , Ouro/química , Humanos , Polietileno/química , Próteses e Implantes , Articulação do Ombro/diagnóstico por imagem , Tomografia Computadorizada por Raios X
17.
Biomed Res Int ; 2019: 2785302, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143771

RESUMO

INTRODUCTION: Various procedures in dental implantology are performed to enhance the bone healing process and implant stability. One of these methods can be a low-level laser therapy (LLLT). OBJECTIVES: The aim of our study was to evaluate the stabilization (primary and secondary) and bone density in peri-implant zone after LLLT protocol using a 635 nm diode laser. MATERIAL AND METHODS: The research included 40 implants placed in the posterior region of a mandible in 24 patients (8 women and 16 man; age: 46.7 ± 8.7 years). The patients were randomly divided into 2 groups G1 (n=12, 18 implants) and G2 (n=12, 22 implants) according to the treatment procedure; G1 (test): 635 nm laser, with handpiece diameter: 8mm, output power: 100mW, spot area: 0.5024cm2, average power density: 199.04mW/cm2, continuous mode, dose: 4J per point (8J/cm2), time: 40 sec per point, 2 points (irradiation on a buccal and a lingual side of the alveolus/implant), and total energy per session 8J; G2 (control): no laser irradiation. The G1 (test) group's implants were irradiated according to the following protocol: 1 day before surgery, immediately after the surgery and 2, 4, 7, and 14 days after. The total energy after all therapeutic sessions was 48J. The implants stability was measured employing a Periotest device (Periotest Test Value: PTV) (measured immediately after the surgery, 7 days, 2 weeks, 4 weeks, and 2 and 3 months after the surgery) and the bone density using cone-beam computed tomography (grayscale value) (measured immediately after the surgery, 4 weeks and 12 weeks after the treatment). RESULTS: The average implant stability at different time points showed lower PTV value (higher stability) at 2nd and 4th week after 635 nm laser irradiation (G1) compared with a control (G2) group (p<0.01). The secondary stability of the implants after 12 weeks observation was not significantly higher for the laser group in contrast to none-irradiated implants (p>0.05). The mean grayscale value at the apical, middle, and cervical level of the titanium implants showed the reduction of pixel grayscale value after 2 weeks and was lower for the G1 group in contrast to the G2 group (p<0.01). The value of grayscale after 12 weeks was significantly higher at the middle and apical level of the implants in the G1group in contrast to the G2 group (p<0.01). CONCLUSION: The application of the 635 nm diode laser enhanced secondary implant stability and bone density. However, to assess the impact of the LLLT on peri-implant bone with different bone densities, further well-controlled long-term trials on larger study groups are needed.


Assuntos
Densidade Óssea/efeitos da radiação , Implantes Dentários , Lasers Semicondutores , Terapia com Luz de Baixa Intensidade , Estudos de Casos e Controles , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
J Cell Physiol ; 234(3): 2807-2821, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30067871

RESUMO

The application of pulsed electromagnetic fields (PEMFs) in the prevention and treatment of osteoporosis has long been an area of interest. However, the clinical application of PEMFs remains limited because of the poor understanding of the PEMF action mechanism. Here, we report that PEMFs promote bone formation by activating soluble adenylyl cyclase (sAC), cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), and cAMP response element-binding protein (CREB) signaling pathways. First, it was found that 50 Hz 0.6 millitesla (mT) PEMFs promoted osteogenic differentiation of rat calvarial osteoblasts (ROBs), and that PEMFs activated cAMP-PKA-CREB signaling by increasing intracellular cAMP levels, facilitating phosphorylation of PKA and CREB, and inducing nuclear translocation of phosphorylated (p)-CREB. Blocking the signaling by adenylate cyclase (AC) and PKA inhibitors both abolished the osteogenic effect of PEMFs. Second, expression of sAC isoform was found to be increased significantly by PEMF treatment. Blocking sAC using sAC-specific inhibitor KH7 dramatically inhibited the osteogenic differentiation of ROBs. Finally, the peak bone mass of growing rats was significantly increased after 2 months of PEMF treatment with 90 min/day. The serum cAMP content, p-PKA, and p-CREB as well as the sAC protein expression levels were all increased significantly in femurs of treated rats. The current study indicated that PEMFs promote bone formation in vitro and in vivo by activating sAC-cAMP-PKA-CREB signaling pathway of osteoblasts directly or indirectly.


Assuntos
Inibidores Enzimáticos/farmacologia , Magnetoterapia , Osteogênese/efeitos da radiação , Osteoporose/terapia , Inibidores de Adenilil Ciclases/farmacologia , Adenilil Ciclases/genética , Adenilil Ciclases/farmacologia , Animais , Densidade Óssea/efeitos da radiação , Diferenciação Celular/efeitos da radiação , AMP Cíclico/antagonistas & inibidores , AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/genética , Modelos Animais de Doenças , Fêmur/crescimento & desenvolvimento , Fêmur/patologia , Fêmur/efeitos da radiação , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Osteoblastos/efeitos da radiação , Osteoporose/genética , Osteoporose/patologia , Ratos , Transdução de Sinais/efeitos da radiação
19.
PLoS One ; 13(12): e0209193, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30562369

RESUMO

PURPOSE: Long-term side effects of the treatments are common in survivors of irradiated pediatric brain tumors. Ionizing radiation in combination with surgery and chemotherapy during childhood may reduce vertebral height and bone mineral density (BMD), and cause growth failure. The aim of this study was to evaluate the late consequences of tumor treatments on vertebrae in survivors of childhood brain tumors. METHODS: 72 adult survivors (mean age 27.8 years, standard deviation 6.7) of irradiated childhood brain tumor were studied by spinal magnetic resonance imaging (MRI) for vertebral abnormalities from the national cohort of Finland. Patients were treated in five university hospitals in Finland between the years 1970 and 2008. Subject height and weight were measured and body mass index (BMI) was calculated. The morphology and height/depth ratio of the vertebrae in the middle of the kyphotic thoracic curvature (Th8) and lumbar lordosis (L3) were examined. Vertebrae were analyzed by Genant's semiquantative (SQ) method and spinal deformity index (SDI) was calculated. BMD was measured by using dual X-ray absorptiometry. RESULTS: 4.2% (3/72) of the patients had undiagnosed asymptomatic vertebral fracture and 5.6% (4/72) of patients had radiation-induced decreased vertebral body height. Male patients had flatter vertebrae compared with females. Patient age at the time of irradiation, BMI and irradiation area correlated to vertebral morphology differentially in males and females. BMD had no association with the vertebral shape. Patients who had received craniospinal irradiation were shorter than the general population. CONCLUSION: Childhood brain tumor survivors had a high number of vertebral abnormalities in young adulthood. Irradiation was associated with abnormal vertebral morphology and compromised final height. Male gender may predispose vertebrae to the side effects of irradiation.


Assuntos
Neoplasias Encefálicas/radioterapia , Lesões por Radiação/diagnóstico por imagem , Radioterapia/efeitos adversos , Doenças da Coluna Vertebral/etiologia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/efeitos da radiação , Absorciometria de Fóton , Adulto , Densidade Óssea/efeitos da radiação , Sobreviventes de Câncer , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Lesões por Radiação/etiologia , Fatores de Risco , Fatores Sexuais , Doenças da Coluna Vertebral/diagnóstico por imagem , Traumatismos da Coluna Vertebral/diagnóstico por imagem , Traumatismos da Coluna Vertebral/etiologia , Fatores de Tempo
20.
BMC Musculoskelet Disord ; 19(1): 424, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30497434

RESUMO

BACKGROUND: The purpose of this study was to evaluate the efficacy of denosumab or zoledronic acid (ZA) using symptomatic skeletal events (SSEs) as the primary endpoint in Asian postmenopausal women with oestrogen-receptor-positive advanced breast cancer. METHODS: Asian postmenopausal women with oestrogen-receptor-positive advanced breast cancer receiving subcutaneous denosumab 120 mg Q4W, or intravenous ZA 4 mg Q4W until the primary analysis cut-off date were retrospectively analysed in the Hong Kong Practice-Based Cancer Research Center(HKCRC) from March 2011 to March 2013. The time to first on-study SSE that was assessed either clinically or through routine radiographic scans was the primary endpoint. RESULTS: 242 patients received denosumab or ZA treatment (n = 120, mean age of 64.9 years (SD 3.01) and n = 122, 65.4 years (3.44), respectively). The median times to first on-study SSE were 14.7 months (12.9-45.6) and 11.7 months (9.9-45.6) for denosumab and ZA, respectively (hazard ratio, HR 0.44, 95% CI 0.71-2.95; p = 0·0002). Compared with the ZA group, denosumab-treated patients had a significantly delayed time to first SSE (HR 0.65 [95% CI 0.29-1.45], p < 0.0001). An increased incidence of SSE was found in the 16-month follow-up with rates of 2.1 and 10.7% for denosumab and ZA, respectively (P = 0.033). The difference persisted with time with rates of 8.3 and 17.2% at the final follow-up, respectively (P < 0.05). CONCLUSION: In postmenopausal women aged ≥60 years with oestrogen-receptor-positive advanced breast cancer, denosumab significantly reduced the risk of developing SSEs compared with ZA. The findings of this pilot trial justify a larger study to determine whether the result is more generally applicable to a broader population.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Reabsorção Óssea/prevenção & controle , Neoplasias da Mama/terapia , Denosumab/uso terapêutico , Ácido Zoledrônico/uso terapêutico , Idoso , Antineoplásicos Hormonais/efeitos adversos , Povo Asiático , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/efeitos da radiação , Reabsorção Óssea/diagnóstico por imagem , Reabsorção Óssea/etiologia , Neoplasias da Mama/complicações , Neoplasias da Mama/patologia , Quimioterapia Adjuvante/efeitos adversos , Feminino , Seguimentos , Hong Kong/epidemiologia , Humanos , Incidência , Mastectomia , Pessoa de Meia-Idade , Pós-Menopausa , Radioterapia Adjuvante/efeitos adversos , Receptores de Estrogênio/metabolismo , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
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