244 resultados para Ossification, Heterotopic


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Collateral cartilage ossification of the distal phalanx in the Brazilian Jumper horse is a common finding. The objective of this study was to evaluate the prevalence and the degree of ossification of the collateral cartilages of the distal phalanx in Brazilian Jumper horses. In an analysis of 652 collateral cartilages from the front feet of 163 horses, 93% of these cartilages had collateral cartilage ossification (P < 0.005), and 7% of these cartilages did not have any type of ossification. In ossified cartilages, 86.4% had ossification beginning from the base, and 6.6% had a separate center of ossification.

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The correct radiographic identification of ossification of the pterygospinous and pterygoalar ligaments plays an important role in surgical procedures for the treatment of trigeminal neuralgia. Most of these procedures are performed through the foramen ovale, a site where these ligaments can be found to be partially or completely ossified. We studied the radiographic features of these ossified ligaments and their location in relation to the foramen ovale by the Hirtz axial technique. For this purpose, 93 dry skulls from the Discipline of Anatomy, São José dos Campos Dental School, UNESP, which presented partial or complete ossification of these ligaments, were radiographed. The pterygospinous ligament was detected on 27.97% of radiographs and was partially ossified in 19.36% of cases and completely ossified in 8.61%. The pterygoalar ligament was present in 62.35% of radiographs, being partially ossified in 49.44% and completely ossified in 12.91%. The pterygospinous ligaments was found to be partially and completely ossified on the same radiograph in 3.23% of cases, whereas the pterygoalar ligament appeared partially and completely ossified on the same radiograph in 6.45%. Furthermore, the pterygospinous ligament was thinner than the pterygoalar ligament and located more medially in relation to the foramen ovale. The pterygoalar ligament formed a large bone bar lateral to the foramen ovale, often obliterating the lumen of the latter. The Hirtz axial technique is an excellent tool for the observation of complete or partial ossification of the pterygospinous and pterygoalar ligaments in surgical procedures for the treatment of trigeminal neuralgia performed through the foramen ovale.

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Fibrodysplasia Ossificans Progressiva (FOP) is a rare, autosomal dominant condition, classically characterised by heterotopic ossification beginning in childhood and congenital great toe malformations; occurring in response to a c.617 G>A ACVR1 mutation in the functionally important glycine/serine-rich domain of exon 6. Here we describe a novel c.587 T>C mutation in the glycine/serine-rich domain of ACVR1, associated with delayed onset of heterotopic ossification and an exceptionally mild clinical course. Absence of great toe malformations, the presence of early ossification of the cervical spine facets joints, plus mild bilateral camptodactyly of the 5th fingers, together with a novel ACVR1 mutation, are consistent with the 'FOP-variant' syndrome. The c.587 T>C mutation replaces a conserved leucine with proline at residue 196. Modelling of the mutant protein reveals a steric clash with the kinase domain that will weaken interactions with FKBP12 and induce exposure of the glycine/serine-rich repeat. The mutant receptor is predicted to be hypersensitive to ligand stimulation rather than being constitutively active, consistent with the mild clinical phenotype. This case extends our understanding of the 'FOP-variant' syndrome.

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O achado de ossificação heterotópica (OH) sobre cicatriz cirúrgica abdominal é um evento raro, mas que soma morbidade ao paciente. Manifesta-se por dor, endurecimento ou desconforto na cicatriz, levando a novas abordagens cirúrgicas. Relatamos um caso de OH no saco herniário incisional com o objetivo precípuo de chamar a atenção para o potencial "totipotente" do fibroblasto, já que sua íntima relação com a OH é inegável. A partir dessa prerrogativa, qualquer forma de tratamento das hérnias incisionais deveria associar o reparo tecidual ao uso de prótese (tela), para enriquecê-lo com os fibroblastos e seus fatores de crescimento celular do próprio paciente, todos autólogos e prontos para uso. A tática é oferecer uma abordagem combinada ou mista, com menores chances de recidiva na correção dessas afecções.

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OBJETIVO: Os pacientes lesado-medulares passam a se submeter a uma nova conformação de forças sobre as articulações. O quadril é uma das mais afetadas, por utilizarem a cadeira de rodas como meio de locomoção. Alterações osteoarticulares, como ossificação heterotópica, podem ser encontradas nesses pacientes, sendo evidenciadas por estudos radiográficos. Este estudo visa identificar a incidência das alterações radiográficas em quadris de paciente lesados medulares. MÉTODOS: Foram avaliados 15 pacientes (30 quadris) acompanhados no Laboratório de Reabilitação Biomecânica do Aparelho Locomotor do HC-Unicamp, analisando-se radiografias da bacia em posições antero-posterior e lowenstein. RESULTADOS: Dos quadris avaliados, apenas sete (23%) não possuíam alguma evidência de dano à superfície articular. A prevalência de ossificação heterotópica encontrada (16,6%) aproximou-se a da literatura. CONCLUSÃO: Devido à prevalência de alterações articulares encontradas, justifica-se o acompanhamento radiográfico dos quadris destes pacientes. Nível de Evidência II. Desenvolvimento de critérios diagnósticos em pacientes consecutivo. (com padrão de referência "ouro" aplicado).

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1. We investigated the effect of a persistent carrageenin- or nystatin-induced inflammatory reaction on heterotopic ossification produced by the subcutaneous implant of a demineralized bone matrix in female Swiss mice (25 to 35 g).2. Subcutaneous carrageenin injection (0.3 ml of a 2% solution in saline) into mice induced an inflammatory reaction characterized by a mature granuloma predominantly of macrophages containing particles of the irritant in their cytoplasm and which remained unchanged until the end of the experiment (40th day).3. Subcutaneous nystatin inoculation (30,000 IU in 0.3 ml saline) induced an inflammatory reaction consisting initially of macrophages (4th day) but later turning into an epithelioid granuloma (7th day) consisting predominantly of epithelioid cells and which was present up to the 2 lst day when it was gradually replaced by adipocytes up to the 30th day.4. An intramuscular implant of demineralized bone matrix (DBM, approximately 10 mg) induced the formation of cartilage and bone tissue and of hemopoietic bone marrow (heterotopic ossification) in 100% of the control animals (N = 5). An intramuscular DBM implant in animals that received carrageenin (N = 19) or nystatin (N = 21) induced heterotopic ossification in 100 and 57% (P<0.01)) of the animals, respectively.5. The response to a dorsal subcutaneous DBM implant was essentially negative in control animals (N = 5), whereas implants performed near the site injected with carrageenin (N = 28) or nystatin (N = 31) produced a response in 71 (P <0.01) and 36 % (P<0.01) of the animals, respectively. A DBM implant into the contralateral (control) dorsal subcutaneous tissue of the same animals that received carrageenin (N = 25) or nystatin (N = 29) resulted in heterotopic ossification in 64 (P<0.01) and 7% of the animals, respectively.6. The results suggest that the macrophages present in the mature granuloma induced by carrageenin somehow favored the development of metaplastic plates after subcutaneous DBM implant and that this effect may be systemic since the same response was observed in contralateral subcutaneous tissue.

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BACKGROUND AND AIMS: Heterotopic ossification (HO) is a pathological bone formation process in which ectopic bone is formed in soft tissue. The formation of bone depends on the expression of the osteoblast phenotype. Earlier studies have shown conflicting results on the expression of phenotype markers of cells originating from HO and normal bone. The hypothesis of the present study is that cells from HO show an altered expression of osteoblast-specific phenotype markers compared to normal osteoblasts. The aims of the study were to further characterize the expression of osteoblast phenotypemarkers and to provide a comparison with other study results. PATIENTS AND METHODS: Using an in vitro technique, reverse transcription polymerase chain reaction (RT-PCR), real-time PCR and immunohistochemistry, we compared the phenotype gene expression (type I collagen, alkaline phosphatase, Cbfa-1, osteocalcin) of osteoblasts from resected HO and normal bone (iliac crest). RESULTS: Cells from HO expressed the osteoblast phenotype (type I collagen, alkaline phosphatase) but were characterized by a depleted osteocalcin expression. The expression of Cbfa-1 (osteocalcin transcription gene) showed a large variety in our study. Preoperative radiotherapy had no effect on phenotype expression in cells from HO. CONCLUSION: Our results provide a characterization of cells originating from HO and support the thesis of an impaired osteoblast differentiation underlying the formation of HO. The transcription axis from Cbfa-1 to osteocalcin could be involved in the pathogenesis of HO.

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Bone development is influenced by the local mechanical environment. Experimental evidence suggests that altered loading can change cell proliferation and differentiation in chondro- and osteogenesis during endochondral ossification. This study investigated the effects of three-point bending of murine fetal metatarsal bone anlagen in vitro on cartilage differentiation, matrix mineralization and bone collar formation. This is of special interest because endochondral ossification is also an important process in bone healing and regeneration. Metatarsal preparations of 15 mouse fetuses stage 17.5 dpc were dissected en bloc and cultured for 7 days. After 3 days in culture to allow adherence they were stimulated 4 days for 20 min twice daily by a controlled bending of approximately 1000-1500 microstrain at 1 Hz. The paraffin-embedded bone sections were analyzed using histological and histomorphometrical techniques. The stimulated group showed an elongated periosteal bone collar while the total bone length was not different from controls. The region of interest (ROI), comprising the two hypertrophic zones and the intermediate calcifying diaphyseal zone, was greater in the stimulated group. The mineralized fraction of the ROI was smaller in the stimulated group, while the absolute amount of mineralized area was not different. These results demonstrate that a new device developed to apply three-point bending to a mouse metatarsal bone culture model caused an elongation of the periosteal bone collar, but did not lead to a modification in cartilage differentiation and matrix mineralization. The results corroborate the influence of biophysical stimulation during endochondral bone development in vitro. Further experiments with an altered loading regime may lead to more pronounced effects on the process of endochondral ossification and may provide further insights into the underlying mechanisms of mechanoregulation which also play a role in bone regeneration.

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This study evaluated the effect of eye muscle area (EMA), ossification, carcass weight, marbling and rib fat depth on the incidence of dark cutting (pH u > 5.7) using routinely collected Meat Standards Australia (MSA) data. Data was obtained from 204,072 carcasses at a Western Australian processor between 2002 and 2008. Binomial data of pH u compliance was analysed using a logit model in a Bayesian framework. Increasing eye muscle area from 40 to 80 cm 2, increased pH u compliance by around 14% (P < 0.001) in carcasses less than 350 kg. As carcass weight increased from 150 kg to 220 kg, compliance increased by 13% (P < 0.001) and younger cattle with lower ossification were also 7% more compliant (P < 0.001). As rib fat depth increased from 0 to 20 mm, pH u compliance increased by around 10% (P < 0.001) yet marbling had no effect on dark cutting. Increasing musculature and growth combined with good nutrition will minimise dark cutting beef in Australia.

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This article explores how the imaginative use of the landscape in Baz Luhrmann’s Australia (2008) intersects with the fantasy of Australianness that the film constructs. We argue the fictional Never-Never Land through which the film’s characters travel is an, albeit problematic, ‘indigenizing’ space that can be entered imaginatively through cultural texts including poetry, literature and film, or through cultural practices including touristic pilgrimages to landmarks such as Uluru and Kakadu National Park. These actual and virtual journeys to the Never-Never have broader implications in terms of fostering a sense of belonging and legitimating white presence in the land through affect, nostalgia and the invocation of an imagined sense of solidarity and community. The heterotopic concept of the Never-Never functions to create an ahistorical, inclusive space that grounds diverse conceptions of Australianness in a shared sense of belonging and home that is as mythical, contradictory and wondrous as the idea of the Never-Never itself. The representations of this landscape and the story of the characters that traverse it self-consciously construct a relationship to past events and to film history, as well as constructing a comfortable subject position for contemporary Australians to occupy in relation to the land, the colonial past, and the present.

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After attending this presentation, attendees will gain awareness of the ontogeny of cranial maturation, specifically: (1) the fusion timings of primary ossification centers in the basicranium; and (2) the temporal pattern of closure of the anterior fontanelle, to develop new population-specific age standards for medicolegal death investigation of Australian subadults. This presentation will impact the forensic science community by demonstrating the potential of a contemporary forensic subadult Computed Tomography (CT) database of cranial scans and population data, to recalibrate existing standards for age estimation and quantify growth and development of Australian children. This research welcomes a study design applicable to all countries faced with paucity in skeletal repositories. Accurate assessment of age-at-death of skeletal remains represents a key element in forensic anthropology methodology. In Australian casework, age standards derived from American reference samples are applied in light of scarcity in documented Australian skeletal collections. Currently practitioners rely on antiquated standards, such as the Scheuer and Black1 compilation for age estimation, despite implications of secular trends and population variation. Skeletal maturation standards are population specific and should not be extrapolated from one population to another, while secular changes in skeletal dimensions and accelerated maturation underscore the importance of establishing modern standards to estimate age in modern subadults. Despite CT imaging becoming the gold standard for skeletal analysis in Australia, practitioners caution the application of forensic age standards derived from macroscopic inspection to a CT medium, suggesting a need for revised methodologies. Multi-slice CT scans of subadult crania and cervical vertebrae 1 and 2 were acquired from 350 Australian individuals (males: n=193, females: n=157) aged birth to 12 years. The CT database, projected at 920 individuals upon completion (January 2014), comprises thin-slice DICOM data (resolution: 0.5/0.3mm) of patients scanned since 2010 at major Brisbane Childrens Hospitals. DICOM datasets were subject to manual segmentation, followed by the construction of multi-planar and volume rendering cranial models, for subsequent scoring. The union of primary ossification centers of the occipital bone were scored as open, partially closed or completely closed; while the fontanelles, and vertebrae were scored in accordance with two stages. Transition analysis was applied to elucidate age at transition between union states for each center, and robust age parameters established using Bayesian statistics. In comparison to reported literature, closure of the fontanelles and contiguous sutures in Australian infants occur earlier than reported, with the anterior fontanelle transitioning from open to closed at 16.7±1.1 months. The metopic suture is closed prior to 10 weeks post-partum and completely obliterated by 6 months of age, independent of sex. Utilizing reverse engineering capabilities, an alternate method for infant age estimation based on quantification of fontanelle area and non-linear regression with variance component modeling will be presented. Closure models indicate that the greatest rate of change in anterior fontanelle area occurs prior to 5 months of age. This study complements the work of Scheuer and Black1, providing more specific age intervals for union and temporal maturity of each primary ossification center of the occipital bone. For example, dominant fusion of the sutura intra-occipitalis posterior occurs before 9 months of age, followed by persistence of a hyaline cartilage tongue posterior to the foramen magnum until 2.5 years; with obliteration at 2.9±0.1 years. Recalibrated age parameters for the atlas and axis are presented, with the anterior arch of the atlas appearing at 2.9 months in females and 6.3 months in males; while dentoneural, dentocentral and neurocentral junctions of the axis transitioned from non-union to union at 2.1±0.1 years in females and 3.7±0.1 years in males. These results are an exemplar of significant sexual dimorphism in maturation (p<0.05), with girls exhibiting union earlier than boys, justifying the need for segregated sex standards for age estimation. Studies such as this are imperative for providing updated standards for Australian forensic and pediatric practice and provide an insight into skeletal development of this population. During this presentation, the utility of novel regression models for age estimation of infants will be discussed, with emphasis on three-dimensional modeling capabilities of complex structures such as fontanelles, for the development of new age estimation methods.

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The distribution, phenotype, and requirement of macrophages for fracture-associated inflammation and/or early anabolic progression during endochondral callus formation were investigated. A murine femoral fracture model [internally fixed using a flexible plate (MouseFix)] was used to facilitate reproducible fracture reduction. IHC demonstrated that inflammatory macrophages (F4/80+Mac-2+) were localized with initiating chondrification centers and persisted within granulation tissue at the expanding soft callus front. They were also associated with key events during soft-to-hard callus transition. Resident macrophages (F4/80+Mac-2neg), including osteal macrophages, predominated in the maturing hard callus. Macrophage Fas-induced apoptosis transgenic mice were used to induce macrophage depletion in vivo in the femoral fracture model. Callus formation was completely abolished when macrophage depletion was initiated at the time of surgery and was significantly reduced when depletion was delayed to coincide with initiation of early anabolic phase. Treatment initiating 5 days after fracture with the pro-macrophage cytokine colony stimulating factor-1 significantly enhanced soft callus formation. The data support that inflammatory macrophages were required for initiation of fracture repair, whereas both inflammatory and resident macrophages promoted anabolic mechanisms during endochondral callus formation. Overall, macrophages make substantive and prolonged contributions to fracture healing and can be targeted as a therapeutic approach for enhancing repair mechanisms. Thus, macrophages represent a viable target for the development of pro-anabolic fracture treatments with a potentially broad therapeutic window...