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Robert A. Mischkowski Max J. Zinser Alexander C. Kübler Barbara Krug Ulrich Seifert Joachim E. Zller 《Journal of cranio-maxillo-facial surgery》2006,34(8):478-483
BACKGROUND: An augmented reality tool for computer assisted surgery named X-Scope allows visual tracking of real anatomical structures in superposition with volume rendered CT or MRI scans and thus can be used for navigated translocation of bony segments. METHODS: In a feasibility study X-Scope was used in orthognathic surgery to control the translocation of the maxilla after Le Fort I osteotomy within a bimaxillary procedure. The situation achieved was compared with the pre-operative situation by means of cephalometric analysis on lateral and frontal cephalograms. RESULTS: The technique was successfully utilized in 5 patients. Maxillary positioning using X-Scope was accomplished accurately within a range of 1mm. The tool was used in all cases in addition to the usual intra-operative splints. A stand-alone application without conventional control does not yet seem reasonable. CONCLUSION: Augmented reality tools like X-Scope may be helpful for controlling maxillary translocation in orthognathic surgery. The application to other interventions in cranio-maxillofacial surgery such as Le Fort III osteotomy, fronto-orbital advancement, and cranial vault reshaping or repair may also be considered. 相似文献
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C. M. Gordon E. Binello M. S. LeBoff M. E. Wohl C. J. Rosen A. A. Colin 《Osteoporosis international》2006,17(5):783-790
Introduction Patients with cystic fibrosis (CF) are known to be at risk for early osteoporosis, and the mechanisms that mediate bone loss
are still being delineated. The aim of the present investigation was to investigate if a correlation exists in these patients
between skeletal measurements by dual-energy x-ray absorptiometry (DXA) and two anabolic factors, dehydroepiandrosterone (DHEA)
and insulin-like growth factor I (IGF-I), and proresorptive factors such as the cytokines interleukin-1β, tumor necrosis factor α,
and interleukin-6.
Methods We studied 32 outpatients (18 females; mean age: 26.2 ± 7.9 years) at a tertiary care medical center. The subjects had venous
samples obtained, underwent anthropometric and bone mineral density (BMD) measurements, and completed a health survey. Serum
IGF-I concentrations were below the age-adjusted mean in 78% of the participants, and DHEA sulfate (DHEAS) concentrations
were low in 72%. Serum concentrations of all cytokines were on the low side of normal; nonetheless, there was a modest inverse
correlation between IL-1β and BMD at all sites.
Results In univariate analyses, IGF-I and DHEAS were significant correlates of BMD or bone mineral content. In final multivariate
models controlling for anthropometric and other variables of relevance to bone density, only IGF-I was identified as a significant
independent skeletal predictor. While alterations in DHEAS, IGF-I, and specific cytokines may contribute to skeletal deficits
in patients with CF, of these factors a low IGF-I concentration appears to be most strongly correlated with BMD.
Conclusions These findings may have therapeutic implications for enhancing bone density in these patients. 相似文献
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Veronique Braud E. Yvonne Jones Andrew McMichael 《European journal of immunology》1997,27(5):1164-1169
Human histocompatibility leukocyte antigen E (HLA-E) and mouse major histocompatibility complex (MHC) class Ib antigen, Qa-1, share the same substitutions at two normally conserved positions 143 and 147, which are likely to affect binding of the C terminus of peptides. Qa-1 is able to bind a peptide derived from the leader sequence of H-2 D and H-2 L molecules. We developed a peptide binding assay in vitro to compare the binding specificity of HLA-E with the mouse MHC class Ib molecule Qa-1. We demonstrate that HLA-E binds, although poorly, the peptide which binds to Qa-1 and that it also binds nonamer signal sequence-derived peptides from human MHC class I molecules. Using alanine and glycine substitutions, we could define primary anchor residues at positions 2 and 9 and secondary anchor residues at position 7 and possibly 3. 相似文献
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Active production of anti-human T-lymphotropic virus type I (HTLV-I) IgM antibody in HTLV-I-associated myelopathy 总被引:2,自引:0,他引:2
Kunihiko Nagasato Tatsufumi Nakamura Ohishi Kiyosumi Kohji Shibayama Masakatsu Motomura Ichinose Katsuhiro Mitsuhiro Tsujihata Shigenobu Nagataki 《Journal of neuroimmunology》1991,32(2):105-109
We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM. 相似文献
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A. Purohit S. Laffer† C. Metz-Favre A. Verot F. Kricek‡ R. Valenta† G. Pauli 《Clinical and experimental allergy》2005,35(2):186-192
BACKGROUND: Results from several studies indicate that the magnitude of immediate symptoms of type I allergy caused by allergen-induced cross-linking of high-affinity Fc epsilon receptors on effector cells (mast cells and basophils) is not always associated with allergen-specific IgE levels. OBJECTIVE: To investigate the association of results from intradermal skin testing, basophil histamine release and allergen-specific IgE, IgG1-4, IgA and IgM antibody levels in a clinical study performed in birch pollen-allergic patients (n = 18). METHODS: rBet v 1-specific IgEs were measured by quantitative CAP measurements and by using purified Fc epsilon RI-derived alpha-chain to quantify IgE capable of binding to effector cells. Bet v 1-specific IgG subclasses, IgA and IgM levels were measured by ELISA, and basophil histamine release was determined in whole blood samples. Intradermal skin testing was performed with the end-point titration method. RESULTS: Our study demonstrates on the molecular level that the concentrations of allergen-specific IgE antibodies capable of binding to Fc epsilon RI and biological sensitivities are not necessarily associated. A moderate association was found between cutaneous and basophil sensitivity. CONCLUSION: Our results highlight the quantitative discrepancies and limitations of the present diagnostic tools in allergy, even when using a single allergenic molecule. The quantity of allergen-specific serum IgE is only one component of far more complex cellular systems (i.e. basophil-based tests, skin tests) used as indirect diagnostic tests for IgE-mediated allergic sensitivity. 相似文献
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目的探讨骨胶原含量在绝经后骨质疏松症的发生、发展及在骨质疏松性骨折中的作用。方法取7个月龄未交配雌性SD大鼠60只,随机分为四组,A组:对照组(sham组);B组:切除卵巢组;C组:切除卵巢+雌激素治疗组;D组:切除卵巢+降钙素治疗组。除A组外,其他三组通过切除双侧卵巢法12周后制成骨质疏松模型,24周后分别行k的力学特性、右侧股骨三点弯曲试验、羟脯氨酸含量、k骨密度(BMD)测定,Masson三色染色法显示骨胶原形态。结果A、C、D组与B组在k羟脯氨酸含量、BMD、k压缩力学参数值、右侧股骨生物力学参数值、骨胶原染色含量及形态方面差异均有统计学意义(P〈0.05),而A、C、D组之间差异无统计学意义(P〉0.05)。统计学分析显示羟脯氨酸含量与BMD及骨生物力学参数值呈直线相关性。结论骨质疏松的发生与骨胶原含量下降有关。骨胶原含量的下降与BMD降低及骨生物力学改变呈相关性。应用雌激素和降钙素治疗去势后骨质疏松大鼠,不仅可以提高其BMD含量和骨生物力学性能,而且还可以提高骨胶原的含量。 相似文献