825 resultados para Ectopic osteogenesis


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Ectopic third molar teeth are those that are impacted in unusual positions, or that have been displaced and are at a distance from their normal anatomic location. Ectopic eruption of a tooth within the oral cavity is common, but rare in other sites. Ectopic eruption can be associated with developmental disturbances, pathologic processes or iatrogenic activity. Male, 19- years old, with an upper left ectopic third molar located in the maxillary sinus-infraorbital region. The patient reported a bad taste and recurrent sinusitis that had been resistant to treatment. Surgical excision was carried out of the third molar tooth using the Caldwell-Luc approach.

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Osteogenesis imperfecta (OI) is a Mendelian disease with genetic heterogeneity characterized by bone fragility, recurrent fractures, blue sclerae, and short stature, caused mostly by mutations in COL1A1 or COL1A2 genes, which encode the pro-alpha 1(I) and pro-alpha 2(I) chains of type I collagen, respectively. A Brazilian family that showed variable expression of autosomal dominant OI was identified and characterized. Scanning for mutations was carried out using SSCP and DNA sequence analysis. The missense mutation c.3235G>A was identified within exon 45 of the COL1A1 gene in a 16-year-old girl diagnosed as having OI type I; it resulted in substitution of a glycine residue (G) by a serine (S) at codon 1079 (p.G1079S). The proband's mother had the disease signs, but without bone fractures, as did five of nine uncles and aunts of the patient. All of them carried the mutation, which was excluded in four healthy brothers of the patient's mother. This is the first description in a Brazilian family with OI showing variable expression; only one among seven carriers for the c.3235G>A mutation developed bone fractures, the most striking clinical feature of this disease. This finding has a significant implication for prenatal diagnosis in OI disease.

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Ectopic eruption of maxillary canines can be associated with root resorption of adjacent teeth. This case report describes and discusses an interesting case of a 15-year-old girl with a Class III malocclusion and an impacted maxillary canine. Because of the unfavorable position of the ectopic canine and the severe root resorption of the maxillary left central and lateral incisors, the treatment options included extraction of the maxillary permanent canines. The mandibular first premolars were extracted to compensate for the Class III malocclusion. A panoramic radiograph taken earlier in the mixed dentition already indicated a possible eruption disturbance of the maxillary left permanent canine. The importance of early diagnosis of maxillary canine ectopic eruption is highlighted in this case report. The early identification of radiographic signs of an ectopic pathway of eruption should be followed by deciduous canine extraction to prevent canine retention and maxillary incisor root resorption. (Am J Orthod Dentofacial Orthop 2012;142:256-63)

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Objective: Information regarding nutrition and body composition in patients diagnosed with osteogenesis imperfecta (OI) is scarce. In the present study, nutritional status, bone mineral density, and biochemical parameters of subjects with Of were evaluated. Methods: Patients with type I OI (n = 13) and type III OI (n = 13) and healthy controls (n = 8) were selected. Nutritional status and bone mineral density were assessed by a 3-d food diary and dual-energy X-ray absorptiometry at the lumbar spine, respectively. Body mass index, serum albumin, calcium, creatinine, cross-linked C-telopeptide, parathyroid hormone, and 25-hydroxivitamin D-3 were also evaluated. Results: Patients with OI had lower bone mineral density (P < 0.05 versus controls). Patients with type III OI had the highest body mass index (P < 0.05 versus patients with type I OI and controls) and the lowest lean body mass (P < 0.05 versus patients with type I OI and controls). In patients with OI, the number of fractures was positively correlated with body mass index (r = 0.581, P = 0.002) and the percentage of body fat (r = 0.451, P = 0.027) and negatively correlated to lean body mass (r = -0.523, P = 0.009). Even when taking dietary supplements, 58% and 12% of subjects with OI did not achieve the calcium and vitamin D recommendations, respectively. Conclusions: Body composition is a risk factor for bone fractures in subjects with OI. Individualized nutritional support is recommended not only to improve body composition but also to potentiate pharmacologic and physical therapies. (C) 2012 Elsevier Inc. All rights reserved.

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Abscisic acid (ABA) is an important regulator of plant responses to environmental stresses and an absolute requirement for stress tolerance. Recently, a third phytoene synthase (PSY3) gene paralog was identified in monocots and demonstrated to play a specialized role in stress-induced ABA formation, thus suggesting that the first committed step in carotenogenesis is a key limiting step in ABA biosynthesis. To examine whether the ectopic expression of PSY, other than PSY3, would similarly affect ABA level and stress tolerance, we have produced transgenic tobacco containing a fruit-specific PSY (CpPSY) of grapefruit (Citrus paradisi Macf.). The transgenic plants contained a single- or double-locus insertion and expressed CpPSY at varying transcript levels. In comparison with the wild-type plants, the CpPSY expressing transgenic plants showed a significant increase on root length and shoot biomass under PEG-, NaCl- and mannitol-induced osmotic stress. The enhanced stress tolerance of transgenic plants was correlated with the increased endogenous ABA level and expression of stress-responsive genes, which in turn was correlated with the CpPSY copy number and expression level in different transgenic lines. Collectively, these results provide further evidence that PSY is a key enzyme regulating ABA biosynthesis and that the altered expression of other PSYs in transgenic plants may provide a similar function to that of the monocot's PSY3 in ABA biosynthesis and stress tolerance. The results also pave the way for further use of CpPSY, as well as other PSYs, as potential candidate genes for engineering tolerance to drought and salt stress in crop plants.

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Adoptive T cell therapy using antigen-specific T lymphocytes is a powerful immunotherapeutic approach against cancer. Nevertheless, many T cells against tumor-antigens exhibit only weak anti-tumoral response. To overcome this barrier it is necessary to improve the potency and anti-tumoral efficacy of these T cells. Activation and activity of T cells are tightly controlled to inhibit unwanted T cell responses and to reduce the risk of autoimmunity. Both are regulated by extrinsic signals and intrinsic mechanisms which suppress T cell activation. The intrinsic mechanisms include the expression of phosphatases that counteract the activation-inducing kinases. Modifying the expression of these phosphatases allows the targeted modulation of T cell reactivity. MicroRNAs (miRNAs) are regulatory small noncoding RNA molecules that control gene expression by targeting messenger RNAs in a sequence specific manner. Gene-specific silencing plays a key role in diverse biological processes, such as development, differentiation, and functionality. miR181a has been shown to be highly expressed in immature T cells that recognize low-affinity antigens.rnThe present study successfully shows that ectopic expression of miR181a is able to enhance the sensitivity of both murine and human T cells. In CD4+ T helper cells as well as in CD8+ cytotoxic T cells the overexpression of miR181a leads to downregulation of multiple phosphatases involved in the T cell receptor signaling pathway. Overexpression of miR181a in human T cells achieves a co-stimulatory independent activation and has an anti-apoptotic effect on CD4+ T helper cells. Additionally, increasing the amount of miR181a enhances the cytolytic activity of murine CD8+ TCRtg T cells in an antigen-specific manner.rnTo test miR181a overexpressing T cells in vivo, a mouse tumor model using a B cell lymphoma cell line (A20-HA) expressing the Influenza hemagglutinin (Infl.-HA) antigen was established. The expression of model antigens in tumor cell lines enables targeted elimination of tumors using TCRtg T cells. The transfer of miR181a overexpressing Infl.-HA TCRtg CD8+ T cells alone has no positive effect neither on tumor control nor on survival of A20-HA tumor-bearing mice. In contrast, the co-transfer of miR181a overexpressing Infl.-HA TCRtg CD8+ and CD4+ T cells leads to improved tumor control and prolongs survival of A20-HA tumor-bearing mice. This effect is characterized by higher amounts of effector T cells and the expansion of Infl.-HA TCRtg CD8+ T cells.rnAll effects were achieved by changes in expression of several genes including molecules involved in T cell differentiation, activation, and regulation, cytotoxic effector molecules, and receptors important for the homing process of T cells in miR181a overexpressing T cells. The present study demonstrates that miR181a is able to enhance the anti-tumoral response of antigen-specific T cells and is a promising candidate for improving adoptive cell therapy.

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http://www.ncbi.nlm.nih.gov/pubmed/20014309

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Background: Distraction of the periosteum results in the formation of new bone in the gap between the periosteum and the original bone. We postulate that the use of a barrier membrane would be beneficial for new bone formation in periosteal distraction. Methods: To selectively influence the contribution of the periosteum, a distraction plate with perforations was used alone or covered by a collagen barrier membrane. All animals were subjected to a 7-day latency period and a 10-day distraction period with a rate of 0.1 mm/day. Four animals per group with or without a barrier membrane were sacrificed at 2, 4, and 6 weeks after the end of the distraction. The height of new bone generated relative to the areas bound by the parent bone and the periosteum was determined by histomorphometric methods. Results: New bone was found in all groups. At the periphery of the distraction plate, significant differences in bone height were found between the hinge and the distraction screw for the group without barrier membrane at 2 weeks (0.39 ± 0.19 mm) compared to 4 weeks (0.84 ± 0.44 mm; P = 0.002) and 6 weeks (1.06 ± 0.39 mm; P = 0.004). Differences in maximum bone height with and without a barrier membrane were observed laterally to the distraction plate at 2 weeks (1.22 ± 0.64 versus 0.55 ± 0.14 mm; P = 0.019) and 6 weeks (1.61 ± 0.56 versus 0.73 ± 0.33 mm; P = 0.003) of the consolidation period. Conclusion: Within the limitations of the present study, the application of a barrier membrane may be considered beneficial for new bone formation induced by periosteal distraction.

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Intraoperative examination of sentinel axillary lymph nodes can be done by imprint cytology, frozen section, or, most recently, by PCR-based amplification of a cytokeratin signal. Using this technique, benign epithelial inclusions, representing mammary tissue displaced along the milk line, will likely generate a positive PCR signal and lead to a false-positive diagnosis of metastatic disease. To better appreciate the incidence of ectopic epithelial inclusions in axillary lymph nodes, we have performed an autopsy study, examining on 100 μm step sections 3,904 lymph nodes obtained from 160 axillary dissections in 80 patients. The median number of lymph nodes per axilla was 23 (15, 6, and 1 in levels 1, 2, and 3, respectively). A total of 30,450 hematoxylin-eosin stained slides were examined, as well as 8,825 slides immunostained with pan-cytokeratin antibodies. Despite this meticulous work-up, not a single epithelial inclusion was found in this study, suggesting that the incidence of such inclusions is much lower than the assumed 5% reported in the literature.

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Background: The relative contributions of different, potential factors to new bone formation in periosteal distraction osteogenesis are unknown. Purpose: The aim of the present study was to assess the influence of original bone and periosteum on bone formation during periosteal distraction osteogenesis in a rat calvarial model by means of histology and histomorphometry. Methods: A total of 48 rats were used for the experiment. The contribution of the periosteum was assessed by either intact or incised periosteum or an occlusive versus a perforated distraction plate. The cortical bone was either left intact or perforated. Animals were divided in eight experimental groups considering the three possible treatment modalities. All animals were subjected to a 7-day latency period, a 10-day distraction period and a 7-day consolidation period. The newly formed bone was analyzed histologically and histomorphometrically. Results: New, mainly woven bone was found in all groups. Differences in the maximum height of new bone were observed and depended on location. Under the distraction plate, statistically significant differences in maximum bone height were found between the group with perforations in both cortical bone and distraction plate and the group without such perforations. Conclusions: If the marrow cavities were not opened, the contribution to new bone formation was dominant from the periosteum. If the bone perforations opened the marrow cavities, a significant contribution to new bone formation originated from the native bone.

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Objectives To describe, using routine data in selected countries, chlamydia control activities and rates of chlamydia infection, pelvic inflammatory disease (PID), ectopic pregnancy and infertility and to compare trends in chlamydia positivity with rates of PID and ectopic pregnancy. Methods Cross-national comparison including national data from Australia, Denmark, the Netherlands, New Zealand, Sweden and Switzerland. Routine data sources about chlamydia diagnosis and testing and International Classification of Disease-10 coded diagnoses of PID, ectopic pregnancy and infertility in women aged 15–39 years from 1999 to 2008 were described. Trends over time and relevant associations were examined using Poisson regression. Results Opportunistic chlamydia testing was recommended in all countries except Switzerland, but target groups differed. Rates of chlamydia testing were highest in New Zealand. Chlamydia positivity was similar in all countries with available data (Denmark, New Zealand and Sweden) and increased over time. Increasing chlamydia positivity rates were associated with decreasing PID rates in Denmark and Sweden and with decreasing ectopic pregnancy rates in Denmark, New Zealand and Sweden. Ectopic pregnancy rates appeared to increase over time in 15–19-year-olds in several countries. Trends in infertility diagnoses were very variable. Conclusions The intensity of recommendations about chlamydia control varied between countries but was not consistently related to levels of chlamydia diagnosis or testing. Relationships between levels of chlamydia infection and complication rates between or within countries over time were not straightforward. Development and validation of indicators of chlamydia-related morbidity that can be compared across countries and over time should be pursued.