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2.
Instr Course Lect ; 70: 415-432, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33438925

RESUMO

Osteochondritis dissecans and cartilage injuries of the knee are among the most challenging clinical entities that pediatric sports medicine specialists encounter. As a weight-bearing joint with significant long-term implications on mobility and overall physical health, the knee also happens to be the most injured or adversely affected joint in preadolescent and adolescent athletes. However, cartilage injuries are unique among other musculoskeletal pathologies in children, in that the healing potential of articular cartilage tissue is limited, and minor injuries or small focal defects can have devastating implications on the lifelong health of the joint. Although the most common form of degenerative joint disease affecting the general population is, of course, osteoarthritis, other conditions such as osteochondritis dissecans or acute, traumatic osteochondral shear injuries can activate their own arthritic pathway, whereby focal injuries precipitate an eventual cascade of diffuse degeneration. Thus, it is important for sports medicine and pediatric orthopaedic specialists alike to understand, diagnose, and initiate early, evidence-based management for cartilage conditions of the knee in pediatric patients. This chapter reviews principles of diagnosis and management of both knee osteochondritis dissecans (a chronic condition of subchondral bone that often secondarily affects the articular cartilage) and acute traumatic cartilage shear injuries. Although the two entities are quite different from an etiologic standpoint, there is significant overlap in technical considerations and treatment principles between these two conditions.


Assuntos
Doenças das Cartilagens , Cartilagem Articular , Osteocondrite Dissecante , Adolescente , Osso e Ossos , Cartilagem Articular/cirurgia , Criança , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteocondrite Dissecante/diagnóstico por imagem , Osteocondrite Dissecante/etiologia
3.
Instr Course Lect ; 70: 453-464, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33438927

RESUMO

Bone and soft-tissue tumors are common in the pediatric population. It is important to be familiar with the appropriate workup, principles of biopsy, differences between unicameral and aneurysmal bone cysts, and principles of managing pathologic fractures in children. The management approach to pediatric soft-tissue masses and some of the recent advances in the field warrant discussion.


Assuntos
Cistos Ósseos Aneurismáticos , Cistos Ósseos , Fraturas Espontâneas , Osso e Ossos , Criança , Fraturas Espontâneas/etiologia , Humanos
4.
Clin Nucl Med ; 46(2): 161-163, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33315674

RESUMO

ABSTRACT: A 75-year-old man with suspected prostate cancer underwent a 99mTc-MDP bone scan to exclude the possibility of bone metastasis. Scans revealed areas of increased tracer uptake in a symmetric distribution on both sides of the pelvis. Further SPECT/CT imaging showed focal 99mTc-MDP accumulation within 2 cystic lesions on both sides of the bladder. Subsequent x-ray cystography showed contrast agent filling within both cystic lesions, which suggested double bladder diverticula. Eventually, these 2 cystic lesions were confirmed by surgery and pathology as double congenital bladder diverticula.


Assuntos
Osso e Ossos/diagnóstico por imagem , Divertículo/diagnóstico por imagem , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Bexiga Urinária/anormalidades , Idoso , Humanos , Masculino , Medronato de Tecnécio Tc 99m , Bexiga Urinária/diagnóstico por imagem
5.
Clin Nucl Med ; 46(1): 34-37, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33181742

RESUMO

A 64-year-old man with history of renal stones and prostate cancer presented for evaluation of osseous metastatic disease due to elevated prostate-specific antigen (13.7 ng/mL). A Tc-labeled bone scan demonstrated unusual linear uptake projecting over the lower pelvis extending into the scrotum. Follow-up CT confirmed a rare case of inguinoscrotal extraperitoneal herniation of the ureter associated with a partially duplicated left renal collecting system. The left-sided inguinoscrotal uptake was within the herniated ureter, potentially mimicking disease within the pelvis.


Assuntos
Osso e Ossos/diagnóstico por imagem , Hérnia/diagnóstico por imagem , Ureter/diagnóstico por imagem , Hérnia/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
6.
Clin Imaging ; 69: 150-157, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32745894

RESUMO

Accidental ingestion of fish bone is a common occurrence in populations that consume unfilleted fish. Although most ingested foreign bodies pass through the gastrointestinal tract uneventfully within a week, less than 1% of patients unfortunately develop gastrointestinal perforation. Occasionally, some patients who are unaware of an episode of fish bone ingestion may present sub-acutely with symptoms mimicking inflammatory conditions or pyrexia of unknown origin. Computed tomography (CT) is the definitive imaging modality in the diagnosis of fish bone foreign body and its complications. This pictorial essay aims to illustrate the various complications related to fish bone ingestion, broadly divided into gastrointestinal related complications and extra-gastrointestinal complications related to migration of fish bone. Radiologists should be familiar with the myriad of possible complications, and take heed that a relevant history of fish bone ingestion is often absent.


Assuntos
Corpos Estranhos , Gastroenteropatias , Animais , Osso e Ossos/diagnóstico por imagem , Ingestão de Alimentos , Corpos Estranhos/complicações , Corpos Estranhos/diagnóstico por imagem , Humanos , Masculino , Alimentos Marinhos/efeitos adversos
7.
Sci Total Environ ; 753: 142351, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33207470

RESUMO

BACKGROUND: Lead (Pb) concentration in bone is a reliable biomarker for cumulative Pb exposure and studying associated health outcomes. However, the standard K-shell fluorescence (KXRF) bone Pb measurement technology has limitations in large-scale population studies. OBJECTIVE: We compared measurements from a portable XRF device and a KXRF device. METHODS: We measured bone Pb concentrations in vivo using portable XRF and KXRF, each measured at the mid-tibia bone in 71 people, 38-95 years of age (mean ± SD = 63 ± 11 years) living in or near three Indiana communities, US; 10 participants were occupationally exposed. We estimated the correlation between bone Pb concentrations measured by both devices. We also examined the extent to which the detection limit (DL) of the portable XRF was influenced by scan time and overlying soft tissue thickness. Finally, we quantified the associations of estimated bone Pb concentration with age and age with soft tissue thickness. RESULTS: The mean bone Pb concentration measured via portable XRF was 12.3 ± 16.7 mg Pb/kg dry bone. The uncertainty of a 3-minute (N = 60) in vivo portable XRF measurement ranged from 1.8 to 6.3 mg/kg, in the context of soft tissue thickness ranging from 2 to 6 mm. This uncertainty was reduced by a factor of 1.4 with 5-minute measurements (N = 11). Bone Pb measurements via portable XRF and KXRF were significantly correlated: r = 0.48 for all participants, and r = 0.73 among participants with soft tissue thickness < 6 mm (72% of the sample). Bone Pb concentrations were higher among participants who were older or were occupationally exposed to Pb. Soft tissue thickness decreased with age. CONCLUSION: With its ease of use, portability, and comparable sensitivity with conventional KXRF systems, the portable XRF could be a valuable tool for non-invasive quantification of bone Pb in vivo, especially for people with thinner soft tissue.


Assuntos
Osso e Ossos , Chumbo , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Indiana , Pessoa de Meia-Idade , Espectrometria por Raios X , Tíbia
8.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 76(11): 1125-1132, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-33229842

RESUMO

PURPOSE: Automated analysis of skeletal muscle in whole-body computed tomography (CT) images uses bone information, but bone segmentation including the epiphysis is not achieved. The purpose of this research was the semantic segmentation of eight regions of upper and lower limb bones including the epiphysis in whole-body CT images. Our targets were left and right upper arms, forearms, thighs, and lower legs. METHOD: We connected two 3D U-Nets in cascade for segmentation of eight upper and lower limb bones in whole-body CT images. The first 3D U-Net was used for skeleton segmentation in whole-body CT images, and the second 3D U-Net was used for eight upper and lower limb bones' segmentation in skeleton segmentation results. Thirty cases of whole-body CT images were used in the experiment, and the segmentation results were evaluated using Dice coefficient with 3-fold cross-validation. RESULT: The mean Dice coefficient was 93% in the left and right upper arms, 89% in the left and right forearms, 95% in the left and right thighs, and 94% in the left and right lower legs. CONCLUSION: Although the accuracy of the segmentation results of relatively small bones remains a challenge, the semantic segmentation of eight regions of upper and lower limb bones including the epiphysis in whole-body CT images has been achieved.


Assuntos
Semântica , Tomografia Computadorizada por Raios X , Osso e Ossos , Extremidade Inferior/diagnóstico por imagem
9.
Int J Nanomedicine ; 15: 8465-8478, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33149587

RESUMO

Introduction: Decellularized matrix from porcine small intestinal submucosa (SIS) endows scaffolds with an ECM-like surface, which enhances stem cell self-renewal, proliferation, and differentiation. Mesoporous bioactive glass (MBG) is extensively recognized as an excellent bio-ceramic for fabricating bone grafts. Materials and Methods: In the current study, SIS was doped on an MBG scaffold (MBG/SIS) using polyurethane foam templating and polydopamine chemistry method. To mimic the bony environment of a natural bone matrix, an ECM-inspired delivery system was constructed by coupling the BMP2-related peptide P28 to a heparinized MBG/SIS scaffold (MBG/SIS-H-P28). The release of P28 from MBG/SIS-H-P28 and its effects on the proliferation, viability, and osteogenic differentiation of bone marrow stromal stem cells were investigated in vitro and in vivo. Results: Our research indicated that the novel tissue-derived ECM scaffold MBG/SIS has a hierarchical and interconnected porous architecture, and superior biomechanical properties. MBG/SIS-H-P28 released P28 in a controlled manner, with the long-term release time of 40 d. The results of in vitro experiments showed improvements in cell proliferation, cell viability, alkaline phosphatase activity, and mRNA expression levels of osteogenesis-related genes (Runx-2, OCN, OPN, and ALP) compared to those of MBG/SIS or MBG/SIS-P28 and MBG/SIS-H-P28. The in vivo results demonstrated that MBG/SIS-H-P28 scaffolds evidently increased bone formation in rat calvarial critical-sized defect compared to that in controls. Conclusion: MBG/SIS-H-P28 scaffolds show potential as ideal platforms for delivery of P28 and for providing a bony environment for bone regeneration.


Assuntos
Ácido Aspártico/química , Materiais Biocompatíveis/farmacologia , Proteína Morfogenética Óssea 2/farmacologia , Osso e Ossos/efeitos dos fármacos , Cerâmica/farmacologia , Matriz Extracelular/metabolismo , Osteoblastos/efeitos dos fármacos , Peptídeos/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Regeneração Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Cinética , Masculino , Camundongos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Porosidade , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Suínos , Tecidos Suporte/química
10.
Medicine (Baltimore) ; 99(46): e23180, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33181695

RESUMO

This study compared implant outcomes following maxillary sinus floor augmentation (MSFA) in edentulous patients with a residual alveolar bone height ≤3 mm. Four techniques were evaluated: 1-stage bone-added osteotome sinus floor elevation procedure (BAOSFE) with simultaneous implant placement; 2-stage BAOSFE with delayed implant placement; 1-stage lateral window sinus floor elevation with simultaneous implant placement; and 2-stage lateral window sinus floor elevation with delayed implant placement. Patients were followed for 18 to 72 months (mean: 52.5 months) after prosthesis placement. Data were analyzed with cone-beam computed tomography. A total of 96 implants from 71 patients were analyzed; pretreatment, there were no significant differences between patients. Total implant survival was 98.9%. The mean residual bone height was significantly higher in the 1-stage BAOSFE group than the other groups (P < .01); 1 implant in this group failed at 3 months. There was no significant difference in total bone height gain between groups. However, the bone height gain of 1st sinus lifting with 2-stage BAOSFE was significantly lower than the 2-stage lateral window procedure (P < .01). There was no prosthesis failure. The favorable implant outcomes suggest these 1-stage and 2-stage MSFA procedures should be considered as alternative treatment options for patients with extremely atrophic posterior maxilla.


Assuntos
Osso e Ossos/cirurgia , Seios Paranasais/cirurgia , Próteses e Implantes/tendências , Levantamento do Assoalho do Seio Maxilar/estatística & dados numéricos , Pesos e Medidas , Osso e Ossos/anormalidades , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Nasais/instrumentação , Procedimentos Cirúrgicos Nasais/métodos , Osteotomia/métodos , Radiografia/métodos , Radiografia/estatística & dados numéricos , Levantamento do Assoalho do Seio Maxilar/instrumentação , Levantamento do Assoalho do Seio Maxilar/métodos , Estatísticas não Paramétricas , Resultado do Tratamento
11.
Int J Periodontics Restorative Dent ; 40(6): e211-e227, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33151185

RESUMO

For decades, the histologic evidence about osseointegration and the bone-implant interface has been discussed in the literature. In this review, the effectiveness of dental implants retrieved for different causes was evaluated. A literature search was performed in databases for papers about implants retrieved from humans published by the Implant Retrieval Center of the University of Chieti-Pescara, Italy. Sixty-eight articles were selected into categories based on topics. The data indicated high level of bone-to-implant contact, lamellar bone close to the surface, roughness related to an increased bone response, organized and remodeled bone after loading, and peri-implant interfaces subjected to a continuous dynamic function.


Assuntos
Implantes Dentários , Osso e Ossos , Implantação Dentária Endo-Óssea , Humanos , Itália , Osseointegração , Estudos Retrospectivos , Propriedades de Superfície
13.
Braz Dent J ; 31(6): 617-622, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33237233

RESUMO

Recent studies suggest that osteoporosis, in addition to the damage caused in long bones, may cause deterioration in the jaws, especially in alveolar bone sites, with effects in the progress of periodontal disease as well as in bone healing. The aim of this study was to evaluate the effect of osteoporosis in the metabolism of rat alveolar bone osteoblasts. There were used 10 female rats divided in two experimental groups (Sham and OVX), which were ovariectomized and after 8 weeks euthanized to collect mandibular bone samples in order to isolate osteoblastic cells. The cells were cultured in 24-well plates to perform the in vitro experiments. After 7, 10 and 14 days, there were evaluated cell proliferation by MTT assay, in situ detection of alkaline phosphatase (ALP) as well as mineralized nodules and expression of genes associated to bone remodeling. Results showed that at 7, 10 and 14 days cell proliferation was lower for OVX group. In situ detection of ALP was higher at 7 days and lower at 10 and 14 days in OVX group. At 17 and 21 days, OVX group had a significative decrease of mineralization nodules. There was a downregulation in the expression of Alp, Bglap and Runx2 genes and an upregulation of Opg in OVX group, whereas Opn and Rankl modulation was similar between the evaluated groups. Our results suggest that osteoporosis has a deleterious effect on alveolar bone cells from ovariectomized rats, which might affect the treatment of diseases associated to the jaw bones.


Assuntos
Osteoporose , Fosfatase Alcalina , Animais , Densidade Óssea , Osso e Ossos , Feminino , Humanos , Osteoblastos , Osteoporose/genética , Ovariectomia , Ratos
14.
Int J Nanomedicine ; 15: 7143-7153, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061372

RESUMO

Introduction: Tobacco mosaic virus-based nanoparticles (TMV VNPs) were previously shown to promote osteogenic differentiation in vitro. This study aims to investigate whether and how TMV VNPs impact on osteoclastogenesis in vitro and bone injury healing in vivo. Methods: Raw264.7 cells were cultured in osteoclastogenic medium in culture plates coated with or without TMV and TMV-RGD1 VNPs, followed by TRAP staining, RT-qPCR and WB assessing expression of osteoclastogenic marker genes, and immunofluorescence assessing NF-κB activation. TMV and TMV-RGD1-modified hyaluronic acid hydrogel were used to treat mouse tibial bone injury. Bone injury healing was checked by micro-CT and Masson staining. Results: TMV and TMV-RGD1 VNPs significantly inhibited osteoclast differentiation and downregulated the expression of osteoclastogenic marker genes Ctr, Ctsk, Mmp-9, Rank, and Trap. Moreover, TMV and TMV-RGD1 VNPs inhibited NF-κB p65 phosphorylation and nuclear translocation, as well as activation of mTOR/AKT signaling pathway. TMV and TMV-RGD1-modified HA hydrogel strongly promoted mouse tibial bone injury with increased bone mass compared to plain HA hydrogel. The amount of osteoclasts was significantly reduced in TMV and TMV-RGD1 treated mice. TMV-RGD1 was more effective than TMV in inhibiting osteoclast differentiation and promoting bone injury repair. Discussion: These data demonstrated the great potential of TMV VNPs to be developed into biomaterial for bone injury repair or replacement.


Assuntos
Nanopartículas/química , Osteogênese , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Vírus do Mosaico do Tabaco/fisiologia , Animais , Osso e Ossos/patologia , Diferenciação Celular/efeitos dos fármacos , Camundongos , NF-kappa B/metabolismo , Nanopartículas/ultraestrutura , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células RAW 264.7 , Ratos , Transdução de Sinais/efeitos dos fármacos , Tíbia/patologia , Cicatrização
15.
PLoS One ; 15(10): e0239861, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33052915

RESUMO

The flanks of the Caucasus Mountains and the steppe landscape to their north offered highly productive grasslands for Bronze Age herders and their flocks of sheep, goat, and cattle. While the archaeological evidence points to a largely pastoral lifestyle, knowledge regarding the general composition of human diets and their variation across landscapes and during the different phases of the Bronze Age is still restricted. Human and animal skeletal remains from the burial mounds that dominate the archaeological landscape and their stable isotope compositions are major sources of dietary information. Here, we present stable carbon and nitrogen isotope data of bone collagen of 105 human and 50 animal individuals from the 5th millennium BC to the Sarmatian period, with a strong focus on the Bronze Age and its cultural units including Maykop, Yamnaya, Novotitorovskaya, North Caucasian, Catacomb, post-Catacomb and late Bronze Age groups. The samples comprise all inhumations with sufficient bone preservation from five burial mound sites and a flat grave cemetery as well as subsamples from three further sites. They represent the Caucasus Mountains in the south, the piedmont zone and Kuban steppe with humid steppe and forest vegetation to its north, and more arid regions in the Caspian steppe. The stable isotope compositions of the bone collagen of humans and animals varied across the study area and reflect regional diversity in environmental conditions and diets. The data agree with meat, milk, and/or dairy products from domesticated herbivores, especially from sheep and goats having contributed substantially to human diets, as it is common for a largely pastoral economy. This observation is also in correspondence with the faunal remains observed in the graves and offerings of animals in the mound shells. In addition, foodstuffs with elevated carbon and nitrogen isotope values, such as meat of unweaned animals, fish, or plants, also contributed to human diets, especially among communities living in the more arid landscapes. The regional distinction of the animal and human data with few outliers points to mobility radii that were largely concentrated within the environmental zones in which the respective sites are located. In general, dietary variation among the cultural entities as well as regarding age, sex and archaeologically indicated social status is only weakly reflected. There is, however, some indication for a dietary shift during the Early Bronze Age Maykop period.


Assuntos
Agricultura/história , Dieta/história , Arqueologia/métodos , Osso e Ossos/química , Isótopos de Carbono/química , Colágeno/análise , Pradaria , História Antiga , Humanos , Isótopos de Nitrogênio/química , Federação Russa
16.
Int J Nanomedicine ; 15: 7523-7551, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116486

RESUMO

During continuous innovation in the preparation, characterization and application of various bone repair materials for several decades, nanomaterials have exhibited many unique advantages. As a kind of representative two-dimensional nanomaterials, graphene and its derivatives (GDs) such as graphene oxide and reduced graphene oxide have shown promising potential for the application in bone repair based on their excellent mechanical properties, electrical conductivity, large specific surface area (SSA) and atomic structure stability. Herein, we reviewed the updated application of them in bone repair in order to present, as comprehensively, as possible, their specific advantages, challenges and current solutions. Firstly, how their advantages have been utilized in bone repair materials with improved bone formation ability was discussed. Especially, the effects of further functionalization or modification were emphasized. Then, the signaling pathways involved in GDs-induced osteogenic differentiation of stem cells and immunomodulatory mechanism of GDs-induced bone regeneration were discussed. On the other hand, their applications as contrast agents in the field of bone repair were summarized. In addition, we also reviewed the progress and related principles of the effects of GDs parameters on cytotoxicity and residues. At last, the future research was prospected.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Grafite/farmacologia , Nanoestruturas/química , Osteogênese/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Osso e Ossos/citologia , Diferenciação Celular/efeitos dos fármacos , Condutividade Elétrica , Grafite/química , Humanos , Osteogênese/fisiologia , Células-Tronco/citologia , Engenharia Tecidual/métodos
17.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(5): 589-593, 2020 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-33085247

RESUMO

The bone morphogenetic protein (BMP) 1/tolloid (TLD) proteinase family is a group of important metalloproteinases, which play key roles in the growth and development of tissues and organs via regulating the biosynthetic processing of the extracellular matrix. Clinical reports have revealed that mutations in the genes encoding BMP1/TLD proteinases lead to dentinogenesis imperfecta type Ⅰ, accompanied with osteogenesis imperfecta. Therefore, this proteinase family is essential for the development of hard tissues. In this study, we review the research progress in the function and mechanism of the BMP1/TLD proteinase family in the development of teeth and bone.


Assuntos
Proteínas Morfogenéticas Ósseas , Osso e Ossos , Proteína Morfogenética Óssea 1/fisiologia , Metaloproteases , Metaloproteases Semelhantes a Toloide
18.
Zhongguo Gu Shang ; 33(10): 954-9, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33107260

RESUMO

OBJECTIVE: To understand changes of coagulation state, microthrombus, microvascular bed and bone density in the osteoporosis model of iron accumulation, and explore the influence of iron accumulation in aspects of osteoporosis on coagulation function and blood vessels. METHODS: Tewnty-four male SPF SD rats aged 6 months were selected, which with the average body weight (250±20) g, which were divided into control group and iron accumulation group according to random number table, 12 rats in each group. Iron accumulation group was intervened by intraperitoneal injection of ferric ammonium citrate 90 mg / kg, and control group was intraperitoneally injected with equal volume of normal saline, twice a week for 9 weeks. After intervention, serum ferritin, coagulation function, microthrombus, vascular density, and three-dimensional morphological reconstruction and spatial structure parameters of the distal femur trabeculae were measured and statistically analyzed. RESULTS: Serum ferritin of iron accumulation group (136.36±35.41) µg / L was higher than control group (68.44±16.86) µg / L(P<0.05). Bone mineral density (BMD) of iron accumulation group (0.167±0.024) g / cm3 was lower than control group(0.400±0.030)g / cm3. Fibrinogen of iron accumulation group (2.03±0.13) g / L was increased than that of control group (1.78±0.46) g / L, D-dimer contents of iron accumulation group (534.95±31.81) ng /ml was increased than that of control group (329.02±84.99) ng /ml, while thrombin time (39.64±2.18) s and prothrombin time(8.70±0.39) s of iron accumulation group were shorter than that of control group (44.92±2.98) s, (9.44±0.49) s (P<0.05). After ink staining, microvessel density in iron accumulation group (17.46±2.07)% was significantly reducedcompared with that of control group(23.81±2.98)%(P<0.05). HE and MSB staining which showed microthrombus in bone marrow of iron accumulation rats, as well as microthrombus in myocardium. CONCLUSION: In the osteoporosis model with the influence of iron accumulation, iron accumulation had a significant influence on the coagulation function, and the blood was relatively hypercoagulable. The bone vascular bed uas reduced, and there were microthrombus in the bone marrow. Hypercoagulable state of blood and formation of microthrombi may be important factors influencing the occurrence of iron accumulation osteoporosis.


Assuntos
Osteoporose , Animais , Densidade Óssea , Osso e Ossos , Ferro , Masculino , Ratos , Ratos Sprague-Dawley
19.
Maturitas ; 141: 63-70, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33036705

RESUMO

During the last decade, a cascade of evidence has questioned the anti-fracture efficacy of vitamin D supplementation. In general, vitamin D status, reflected by serum 25-hydroxy-vitamin D [25(OH)D] concentrations, seems to predict fracture risk and bone mineral density (BMD). Despite the well-documented detrimental effect of vitamin D deficiency on bones, vitamin D monotherapy does not seem to reduce the risk of fractures. On the other hand, high vitamin D doses, either at monthly (60,000-100,000 IU) or daily intervals (>4000 IU), appear to be harmful with regard to falls, fracture risk and BMD, especially for people without vitamin D deficiency and at low fracture risk. Therefore, a U-shaped effect of vitamin D on the musculoskeletal system may be supported by the current evidence. Vitamin D supplementation could be of value, at daily doses of at least 800 IU, co-supplemented with calcium (1000-1200  mg/day), in elderly populations, especially those with severe vitamin D deficiency [25(OH)D <25-30  nmol/L (<10-12  ng/mL)], although its anti-fracture and anti-fall efficacy is modest. Good compliance and at least 3-5 years of therapy are required.


Assuntos
Densidade Óssea/efeitos dos fármacos , Fraturas Ósseas/prevenção & controle , Vitamina D/administração & dosagem , Acidentes por Quedas , Idoso , Osso e Ossos/efeitos dos fármacos , Cálcio na Dieta/administração & dosagem , Suplementos Nutricionais , Fraturas Ósseas/etiologia , Humanos , Vitamina D/efeitos adversos , Vitamina D/análogos & derivados , Deficiência de Vitamina D/complicações , Vitaminas/uso terapêutico
20.
Crit Rev Oncol Hematol ; 156: 103126, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113487

RESUMO

Osteosarcoma (OS) is the most common cancer of bone. Jaw osteosarcoma (JOS) is rare and it differs from long-bone OS (LBOS) in terms of the time of onset (two decades later), lower metastatic spread, and better survival. OS is characterized by the proliferation of osteoblastic precursor cells and the production of osteoid or immature bone. OS arises from a combination of genetic aberrations and a favourable microenvironment. This local microenvironment includes bone cells, blood vessels, stromal cells, and immune infiltrates, all of which may constitute potential targets for anti-cancer drugs. Differences in the clinical and biological behaviour of JOS versus LBOS are likely to at least in part be due to differences in the microenvironment between the two sites. The present review provides a brief overview of the known pathophysiological parameters involved in JOS.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Osso e Ossos , Humanos , Nigéria , Células Estromais , Microambiente Tumoral
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