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861.
Malignant peripheral nerve sheath tumor (MPNST) is an uncommon soft tissue neoplasm with a poor prognosis, occurring sporadically or associated with neurofibromatosis type 1 (NF1); however, the histogenesis of MPNST remains unclear, especially in sporadic tumors. There are two major forms of genomic instability in human cancer: chromosomal instability (CIN) and microsatellite instability (MSI). An inverse relationship has recently been demonstrated between CIN and MSI in colorectal cancers. CIN and MSI are suggested to be individual pathways, which are involved in the pathogenesis and which may lead to specific clinical and pathological characteristics. To elucidate the chromosomal aberration as a consequence of CIN and MSI status of MPNST, we karyotyped 10 MPNSTs from nine patients, and examined the MSI of seven microsatellite markers using high-resolution fluorescence microsatellite analysis; 2 out of 10 cases (20%) had normal karyotypes, and 8 out of 10 cases (80%) revealed structural and numerical chromosomal aberrations. Three of the 10 cases (30%) showed near triploidy. The most frequent aberration was -22 (40%), followed by +2, +14, -13, -17, and -18 (30% each). An MSI-low status was observed in 30% of cases; the remaining cases showed microsatellite stability. These findings suggest that chromosomal aberration as a consequence of CIN has a greater role in the pathogenesis of MPNST than does that due to MSI.  相似文献   
862.
It has been suggested that prostate cancer spread has predictable patterns, with prostate cancers known to affect the prostatic contours. However, few systematic investigations have documented the associated contour alterations, especially at a clinically localized stage. The purpose of the present paper was to objectively evaluate prostatic contour alterations based on left-right asymmetry, and analyze the histopathological features and prognostic impact. One hundred and sixty-two asymmetrical contours with left-right asymmetry in the length >or=10%, and 278 cancer foci were observed in 114 radical prostatectomy specimens. Of the asymmetrical contours, 55 (34%) were caused by cancer, and of the cancer foci, 55 (20%) generated asymmetrical contours. Cancer-associated asymmetries showed significant correlations with aggressive behaviors such as cancer volume, Gleason score, positive surgical margin, and extraprostatic extension, although these were not significantly associated with unfavorable prognosis. The authors present basic data relating to altered prostatic contours, such as spatial distribution and causative pathological conditions. Clinicopathological characteristics concerning cancer-associated contour alterations, are also presented in detail.  相似文献   
863.
We examined multiunit responses to tones and to 1/3 and 2/3 octave band-pass noise (BPN) in the marmoset primary auditory cortex (A1) and the caudomedial belt (CM). In both areas, BPN was more effective than tones, evoking multiunit responses at lower intensity and across a wider frequency range. Typically, the best responses to BPN remained at the characteristic frequency. Additionally, in both areas responses to BPN tended to be of greater magnitude and shorter latency than responses to tones. These effects are consistent with the integration of more excitatory inputs driven by BPN than by tones. While it is generally thought that single units in A1 prefer narrow band sounds such as tones, we found that best responses for multi units in both A1 and CM were obtained with noises of narrow spectral bandwidths.  相似文献   
864.
865.
This study was designed to analyze the subcellular localization of E-cadherin and β-catenin both of which play a critical role in cell–cell adhesion in uterine carcinosarcoma (UCS). We performed an immunohistochemical reaction analysis of the subcellular localization of E-cadherin and β-catenin proteins in 46 cases of UCSs consisting of 28 UCSs with heterologous sarcoma and 18 UCSs with homologous sarcoma and compared their clinicopathological features. In most UCSs, membranous expression of E-cadherin and β-catenin was completely lost in sarcomatous components, but it was preserved in carcinomatous components. Nuclear β-catenin expression was observed significantly more frequently in sarcomatous components (31/46, 67.4%) than in carcinomatous components (22/46, 47.8%; P = 0.0025). In sarcomatous components, nuclear β-catenin expression was found significantly more frequently in heterologous sarcoma (23/28, 82.1%) than in homologous sarcoma (8/18, 44.4%; P = 0.0279). The stage was the only independent prognostic significant factor. These results suggest that reduced membranous expression of E-cadherin and β-catenin may contribute to the biphasic morphology of UCS. Furthermore, although the precise mechanism is unclear, nuclear β-catenin expression in sarcomatous components may also be associated with biphasic morphology and heterologous sarcomatous differentiation.  相似文献   
866.
Ewing sarcoma-primitive neuroectodermal tumor (EWS) is associated with the most unfavorable prognosis of all primary musculoskeletal tumors. The objective of the present study was to investigate whether tumor-associated macrophages (TAMs) affect the development of EWS. TAMs were isolated from mouse xenografts using CD11b magnetic beads and examined for their cytokine expression and osteoclastic differentiation. To evaluate the role of TAMs in xenograft formation, liposome-encapsulated clodronate was used to deplete TAMs in mice. Macrophage infiltration and tumor microvascular density were histologically evaluated in 41 patients with EWS, and association with prognosis was examined using Kaplan-Meier survival analysis. In mouse EWS xenografts, TAMs expressed higher concentrations of cytokines including interleukin-6, keratinocyte-derived chemokine, and monocyte chemotactic protein-1. TAMs were more capable than normal monocytes of differentiating into tartrate-resistant acid phosphatase-positive giant cells. Depleting macrophages using liposome-encapsulated clodronate significantly inhibited development of EWS xenografts. In human EWS samples, higher levels of CD68-positive macrophages were associated with poorer overall survival. In addition, enhanced vascularity, increase in the amount of C-reactive protein, and higher white blood cell counts were also associated with poor prognosis and macrophage infiltration. TAMs seem to enhance the progression of EWS by stimulating both angiogenesis and osteoclastogenesis. Further investigation of the behavior of TAMs may lead to development of biologically targeted therapies for EWS.  相似文献   
867.
Tracheoinnominate artery fistula is a well-known complication that arises on using a cannula. Therefore, routine examination of the anatomical relationship of the innominate artery and trachea should be carried out. We evaluated the usefulness of magnetic resonance imaging in 5 patients with severe motor and intellectual disabilities (SMID) using a combination of true-fast imaging of steady-state precession (true-FISP) sequences and two-dimensional prospective acquisition correction (2D-PACE). For all patients, the trachea and the innominate artery were identified without sedation and contrast media. In one patient, the innominate artery was observed to be pressing on the trachea. In three patients, the trachea and innominate artery were brought very close each other, and in the other patient the anatomical relationship of the trachea and surrounding structure was delineated before tracheotomy. The validity of true-FISP sequences combined with the respiratory-gated technique was confirmed useful for the patients who are difficult to lie quietly and to hold their breath voluntarily.  相似文献   
868.
We report a case of lipomatous hypertrophy, which is a relatively uncommon entity. The patient presented with premature atrial conduction and echocardiography showed a large intracardiac mass in the right atrium. He underwent successful resection of the mass with septal reconstruction using autologous pericardium. Pathological examination revealed benign fatty infiltration suggestive of benign lipomatous hypertrophy.  相似文献   
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