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41.
We report a 66-year-old man with a spinal, extradural solitary fibrous tumor showing unique retiform and papillary architecture. The patient presented in May 2008 with worsening right-sided lower back pain and urinary frequency. Magnetic resonance imaging of the spine documented a heterogeneously enhancing dumbbell-shaped extradural lesion causing cord compression at T11/12 level. The tumor extended to the paravertebral soft tissue and invaded the right adjacent vertebral pedicles and laminae. An angiogram showed prominent vascular supply mainly from the right T11 radicular artery. The patient underwent surgery to relieve cord compression in May 2008 and a second operation following embolization with coils in October 2009. No recurrence was observed at the last neuroimaging follow-up in June 2012. The tumor was composed of vimentin, CD34, Bcl-2, and CD99-positive rounded or slightly elongated cells with scant cytoplasm and oval to spindle nuclei. Several pseudovascular spaces reminiscent of the rete testis were present, and several of them contained papillary projections. Cytologic atypia was minimal, and mitotic activity was low. Focal infiltration of the paraspinal adipose tissue was seen at microscopic level. To our knowledge, retiform and papillary features have never been reported in a solitary fibrous tumor.  相似文献   
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Biological tissues (including oral mucosa) can absorb and re‐emit specific light wavelengths, detectable through spectrophotometric devices. Such a phenomenon is known as “autofluorescence” (AF). Several devices evaluating tissue AF have been developed and commercialized in the last two decades. Among these, the VELscope® system has been proposed as a visual diagnostic aid for potentially malignant disorders and malignant lesions of the oral mucosa. In the present pilot study, we investigated which are the main histopathological features possibly related to variations in AF patterns in a set of 20 oral squamous cell verrucous carcinoma. Among all the histological features investigated, only the mean width of keratin was significantly different between hypofluorescent and hyperfluorescent carcinomas. The results of the present study demonstrate that AF features of oral malignant lesions are significantly associated with the width of their keratin layer.  相似文献   
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In this paper, a new strategy for highly selective and sensitive direct detection of lymphoma cells by exploiting the interaction between a peptide and its B-cell receptor, has been evaluated. In particular, an idiotype peptide, able to specifically bind the B-cell receptor of A20 cells in mice engrafted with A20 lymphoma, has been used as molecular probe. The new detection technique has been demonstrated on a planar crystalline silicon chip. Coverage of 85% of silicon surface and detection efficiency of 8.5 × 10−3 cells/μm2 were obtained. The recognition strategy promises to extend its application in studying the interaction between ligands and their cell-surface receptors.OCIS codes: (000.1430) Biology and medicine, (280.1415) Biological sensing and sensors  相似文献   
46.

Background

Immunoglobulin light chains are classified as middle molecule uremic toxins able to interact with B lymphocyte membranes leading to the activation of transmembrane signaling. The ensuing impairment of neutrophil function can contribute to the chronic inflammation state of uremic patients, and the increased risk of bacterial infections or vascular calcifications. The aim of this crossover observational study was to assess the difference in free light chain removal by three different hemodialysis filters in patients not affected by multiple myeloma.

Methods

Free light chain removal was compared in the polymethylmethacrylate (PMMA) membrane Filtryzer BK-F, the polyphenylene HFR17 filter and the conventional polysulfone filter F7HPS. Twenty chronic hemodialysis patients were enrolled: mean age was 67.7?±?17.0 years, M/F?=?14/6, dialysis vintage (months) 25.5?±?32.0. The patients were randomized into two groups of treatment lasting 6 weeks each. The dialysis sessions checked were the midweek sessions and the blood was drawn at times 0, 120’ and 240’. Kappa (k) and lambda (λ) light chain levels, β2microglobulin (β2M), C reactive protein (CRP) and albumin were checked.

Results

K light chain levels were 345.0?±?100.0 mg/L, λ light chains were 121.4?±?27.0 mg/L. The values of k light chains at times 120’ and 240’ were significantly lower with PMMA and HFR17 than those obtained with F7. The reduction ratio per session (RRs) for k light chains was 44.1?±?4.3% with HFR17, 55.3?±?3.4% with PMMA, 25.7?±?8.3% with F7 (p?=?0.018). The RRs for λ light chains was 30.3?±?2.9% with HFR17, 37.8?±?17.3% with PMMA, 14.0?±?3.9% with F7 (p?=?0.032). As to β2M, RRs was 42.4?±?3.2% with HFR17 vs. 33.9?±?2.8% with PMMA vs. 6.3?±?1.9% with F7 (p?=?0.022). The three filters tested showed no differences in CRP or albumin levels.

Conclusion

In terms of light chain and β2M removal, the PMMA and on-line HFR filters are similar and both are significantly more effective than the F7 filter in chronic dialysis patients.

Trial registration

The present trial was registered retrospectively (NCT02950389, 31/10/2016).
  相似文献   
47.
The aim of this study was to determine how risks associated with skydiving can be managed within acceptable limits. Using “Course-of-Action” theory described by Theureau, four experienced skydivers viewed recordings of their jumps, from preparation to landing, to elicit their perceptions of these experiences. The sequences dealing with safety concerns were then extracted. Data analysis revealed seven typical sequences of activity to manage safety, labeled “To check the material during preparation,” “To feel prepared and safe for the jump as the plane gains altitude,” “To use the time of freefall,” “To deploy the parachute,” “To fly safely,” “To ensure a safe landing” and “To organize the structured packing of the parachute.” These results showed how the skydivers mitigated safety risks through a heightened awareness of critical elements in the unfolding jump activity and sequences of distributed and timed concerns and actions. The implications for accident analysis, prevention and education for training in risky sports activity are provided.

Key points

  • The skydivers’ activity could be broken down into seven safety sequences.
  • Each safety sequence was defined by specific involvements and directions at the very moment of the situation.
  • Skydivers’ safety concerns are embedded in the succession of two types of temporal horizon organization: immediate and short-term.
Key words: Skydiving, situated action, activity, meaning, training, involvement, subjective experience, education  相似文献   
48.
Despite the high prevalence of depressive disorders in cancer patients and elderly people, the topic of depression in elderly cancer patients still remains unexplored. This emerges from a systematic review of the literature conducted to investigate issues of depression, diagnosis, pathogenesis, treatment and their complex neuroimmunobiological interactions. Indeed, it becomes apparent that depression in elderly patients with cancer may have a peculiar phenomenology. In addition, the moderate rate of major depressive disorder and the high rate of minor depressive disorder are accompanied by subthreshold forms of depression that are at risk to be underrecognized and untreated. Immune dysfunction may represent a common pathogenic ground of depression, cancer and aging. This may have important implications for treatment. In the near future, we need to develop validated mood disorder diagnoses and verify antidepressant treatment efficacy for elderly cancer patients with depression in order to improve their clinical outcome and quality of life.  相似文献   
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