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31.
We describe a 10-month-old boy with 22q13 deletion syndrome. Chromosomal analysis showed a partial duplication of 22p11.2-pter and a terminal deletion of 22q13.31-qter. Maternal chromosomal analysis showed a pericentric inversion of chromosome 22, with breakpoints at p11.2 and q13.31 [inv(22)(p11.2q13.31)]. The deleted chromosome resulted from a recombinant chromosome inherited from his mother. This is a rare case of 22q13 deletion syndrome associated with parental pericentric inversion of chromosome 22.  相似文献   
32.
We herein report a 36-year-old man with repeated necrotizing lymphadenitis due to MEFV gene mutations. The patient''s chief complaints were a fever and painful cervical lymphadenopathy. We diagnosed him with necrotizing lymphadenitis based on the pathological findings of the lymph nodes and the exclusion of other differential diseases. The same episode recurred four times. We speculated the involvement of autoinflammatory backgrounds and detected MEFV gene mutations of E148Q (homo), P369S, and R408Q. Considering the elevation of interleukin-18, these mutations probably played roles in the repeated necrotizing lymphadenitis.  相似文献   
33.
The purpose of this study was to evaluate the effects of prone positioning on pulmonary perfusion using flow-sensitive alternating inversion recovery (FAIR), a noninvasive magnetic resonance imaging technique that requires no contrast medium. Seven healthy volunteers were studied in the supine and prone positions under three respiratory conditions: normal breathing of room air, unassisted breathing of 45% O2, and controlled mechanical ventilation (CMV) with positive end-expiratory pressure. Signal intensities (SIs) were obtained from ventral, middle, and dorsal regions on sagittal lung images and dependent/nondependent SI ratios were calculated to evaluate pulmonary perfusion distribution. In the supine position, SIs increased significantly from the ventral to dorsal region under all three respiratory conditions and prone positioning inverted the perfusion distribution under all conditions. Right lung SI ratios were 2.34 ± 0.29, 2.74 ± 0.66, and 2.42 ± 0.73 in the supine position and 1.68 ± 0.48, 1.78 ± 0.36, and 1.92 ± 0.21 in prone for room air, 45% O2, and CMV, respectively. The difference between supine and prone positions was statistically significant. The left lung showed a similar pattern and the difference was significant only under CMV. No difference was observed between the different respiratory conditions in both lungs. This study demonstrated that the distribution of pulmonary perfusion was more uniform in prone than in the supine position.  相似文献   
34.
Purpose Motion artifact is problematic in the diagnosis of Creutzfeldt-Jakob disease (CJD) because of dementia. The purpose was to compare the occurrence of this artifact between a diffusion-weighted (DW) magnetic resonance (MR) imaging sequence and conventional sequences. Materials and methods Ten MR examinations comprising T2-weighted, T1-weighted, DW, and fluid-attenuated inversion recovery imaging in seven CJD patients were retrospectively evaluated. The occurrence of motion artifacts on each sequence were assessed, and the examination was classified into four groups as follows: group A, motion artifact not revealed on DW imaging but revealed on one or more other sequences; group B, revealed on DW imaging and one or more other sequences; group C, not revealed on any sequences; and group D, revealed on DW imaging but not on any other sequences. Results The 10 MR examinations were classified as eight group A (80%), one B (10%), one C (10%), and zero D (0%). Conclusion Motion artifacts are likely to occur in any conventional imaging sequences in CJD, but the fast-imaging ability of DW imaging can reduce this artifact. The combination of an absence of motion artifact on DW imaging and the presence on conventional sequences may be one of the frequent findings of CJD.  相似文献   
35.
 A 15-year-old girl who developed traumatic iliacus hematoma and complete paralysis of the quadriceps muscle is reported. The current case and literature review revealed that incomplete quadriceps paralysis associated with traumatic iliacus hematoma is likely to progress to complete paralysis in days or weeks as a result of increased intracompartmental pressure. However, surgical decompression of the femoral nerve could produce good results even in patients who have complete quadriceps paralysis preoperatively. Received: April 9, 2002 / Accepted: June 28, 2002 Offprint requests to: K. Tamai  相似文献   
36.
Endoplasmic reticulum (ER) stress response is important for protein maturation in the ER. Some murine models for bone diseases have provided significant insight into the possibility that pathogenesis of osteoporosis is related to ER stress response of osteoblasts. We examined a possible correlation between osteoporosis and ER stress response. Bone specimens from 8 osteoporosis patients and 8 disease-controls were used for immunohistochemical analysis. We found that ER molecular chaperones, such as BiP (immunoglobulin heavy-chain binding protein) and PDI (protein-disulfide isomerase) are down-regulated in osteoblasts from osteoporosis patients. Based on this result, we hypothesized that up-regulation of ER molecular chaperones in osteoblasts could restore decreased bone formation in osteoporosis. Therefore, we investigated whether treatment of murine model for osteoporosis with BIX (BiP inducer X), selective inducer BiP, could prevent bone loss. We found that oral administration of BIX effectively improves decline in bone formation through the activation of folding and secretion of bone matrix proteins. Considering these results together, BIX may be a potential therapeutic agent for the prevention of bone loss in osteoporosis patients.  相似文献   
37.
Solitary fibrous tumors (SFT) have recently been established to be of mesenchymal origin. Although there are numerous reports of SFTs arising from the pleura, reports of the tumor arising from extrapleural sites are comparatively rare [Fletcher CDM, Unni K, Mertens F (eds) World Health Organization classification of tumors, pathology & genetics, tumors of soft tissue and bone. IARC Press, Lyon, pp 86–901, 2002]. We report a case of SFT arising in the inguinal region.  相似文献   
38.
Subchondral bone is a candidate for treatment of osteoarthritis (OA). We investigated the effects of intra‐articular injection of hyaluronan (IAI‐HA) on subchondral bone in rabbit OA model. OA was induced by anterior cruciate ligament transection, with some rabbits receiving IAI‐HA. OA was graded morphologically, and expression of mRNA was assessed by real‐time RT‐PCR. Tissue sections were stained with hyaluronan‐binding protein, and penetration of fluorescent hyaluronan was assessed. The in vitro inhibitory effect of hyaluronan on MMP‐13 was analyzed in human osteoarthritic subchondral bone osteoblasts (OA Ob) by real‐time RT‐PCR and ELISA. Binding of hyaluronan to OA Ob via CD44 was assessed by immunofluorescence cytochemistry. Expression of MMP‐13 and IL‐6 mRNA in cartilage and subchondral bone, and morphological OA grade, increased over time. IAI‐HA ameliorated the OA grade and selectively suppressed MMP‐13 mRNA in subchondral bone. IAI‐HA enhanced the hyaluronan staining of subchondral bone marrow cells and osteocyte lacunae. Fluorescence was observed in the subchondral bone marrow space. In OA Ob, hyaluronan reduced the expression and production of MMP‐13, and anti‐CD44 antibody blocked hyaluronan binding to OA Ob. These findings indicate that regulation of MMP‐13 in subchondral bone may be a critical mechanism during IAI‐HA. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:354–360, 2011  相似文献   
39.
The iliac crest bone grafting (ICBG) technique for lumbar posterolateral fusion surgery is widely used; however, donor site problems such as pain and sensory disturbance have been reported. Local bone is available for fusion surgery, but its reliability as a graft has not been fully reported. In the current study, we examined single-level instrumented posterolateral fusion with a local bone graft versus an ICBG in a prospective randomized study. Eighty-two patients diagnosed with L4 degenerated spondylolisthesis were divided into two groups at random. Forty-two patients underwent instrumented posterolateral fusion with a local bone graft (L4–L5 level), and 40 patients underwent instrumented posterolateral fusion with an ICBG (L4–L5 level). Rate and duration of bone union, visual analog scale (VAS) score, Japanese orthopedic association score (JOAS), Oswestry Disability Index (ODI), and complications were evaluated before and 2 years after therapy. VAS score, JOAS, and ODI were not significantly different between the two groups before and after surgery (P > 0.05). Rate and average duration of bone union were 90% and 8.5 months in the local bone graft group, and 85% and 7.7 months in the ICBG group, but without significant difference (P > 0.05). Prolonged surgical time and complications such as donor site pain (8 patients) and sensory disturbance (6 patients) were observed in the ICBG group. If single-level posterolateral fusion was performed, local bone graft technique has the same bone union rate compared with ICBG, requires less surgical time, and has fewer complications.  相似文献   
40.
BACKGROUND: We describe immunomodulatory effects of FK734, a humanized version of a mouse anti-human CD28 mAb (clone TN228), in vitro and in a chimeric human-mouse model of allograft rejection. METHODS: Cytokine production and proliferation were assessed in a mixed lymphocyte reaction containing FK734, human T cells, and endothelial cells or monocytes. FK734 was also administered to SCID mice engrafted with human skin and adoptively transferred with human peripheral blood mononuclear cells allogeneic to the skin graft. RESULTS: In vitro, FK734 enhanced secretion of interleukin-2 and interferon-gamma as well as proliferation of CD4+ and CD8+ T cells stimulated by allogeneic human leukocyte antigen (HLA)-DR+ human umbilical vein endothelial cells (which lack B7 molecules and FcgammaRs) or by blood monocytes (which express low levels of B7 molecules and FcgammaRs) compared with control mAb, but these effects were significantly smaller than those provided by mAb 28.2, a stimulatory mouse anti-human CD28 mAb, at comparable concentrations. However, FK734 generally inhibited cytokine secretion and T cell proliferation in cocultures with human umbilical vein endothelial cells transduced to express CD86. In vivo using SCID/beige mice bearing human skin with adoptively transferred peripheral blood mononuclear cells, administration of FK734 protected human endothelial cell-lined microvessels, significantly but incompletely reducing endothelial cell injury and T cell infiltration into the graft one or two weeks later. CONCLUSIONS: FK734 is a partial agonist of CD28 signaling that can reduce human T cell alloresponses in the presence of strong costimulation by B7 molecules in vitro and can reduce T cell-mediated skin allograft rejection in vivo.  相似文献   
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