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1.
We employ diffuse optical tomography (DOT) to track treatment progress in a female subject presenting with locally advanced invasive carcinoma of the breast during neoadjuvant chemotherapy. Three-dimensional images of total hemoglobin concentration and scattering identified the tumor. Our measurements reveal tumor shrinkage during the course of chemotherapy, in reasonable agreement with magnetic resonance images of the same subject. A decrease in total hemoglobin concentration contrast between tumor and normal tissue was also observed over time. The results demonstrate the potential of DOT for measuring physiological parameters of breast lesions during chemotherapy.  相似文献   
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Tracheoesophageal fistula is a life threatening condition. Patients not managed surgically ultimately die of their disease. Surgical management is the treatment of choice. We present a case of a patient that developed a tracheoesophageal fistula after tracheostomy. Surgical repair was done which failed due to infection. The patient was managed with the help of an esophageal stent and Trichloroacetic Acid cautery. This approach can be used in selected patients, depending upon the size and site of TEE Larger fistulae and those situated lower down e.g. supra carinal cannot be managed by this technique.  相似文献   
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Aurones are a class of well-studied natural compounds primarily responsible for the yellow pigment in flowering plants and have been shown to have fluorescent properties as well as beneficial biological effects. Traditionally, aurones can be easily synthesized through a Knoevenagel condensation of benzofuranones with arylaldehydes. Recently, Kafle et al. unexpectedly synthesized a new aurone derivative containing a 1,2,3-triazole within its backbone. Since, 1,2,3-triazole containing structures have been shown to be useful as fluorophores with large Stokes shifts, we hypothesized that these new aurone-derived triazole compounds (ATs) could be utilized as potential fluorophores. Here we describe a newly-synthesized fluorescent compound which has potential for use as a live-cell probe, having a large Stokes shift of 118.3 ± 1.01 nm in phosphate-buffered saline with the benefit of increased fluorescence in protic environments, which is uncommon in aurone-derived fluorophores.

Aurones are a class of naturally occurring compounds with fluorescent derivatives. Here we show a newly synthesized derivative of aurones containing a 1,2,3-triazole which is fluorescent in aqueous environments and has potential to be used as a probe in vitro.  相似文献   
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Background: Myeloid sarcoma (MS) is characterized by extramedullary infiltration by immature myeloid cells. Owing to rarity of this disease, the clinical features and overall outcomes are yet to be clarified.

Objective: To define clinical characteristics, epidemiology, pathologic findings, treatment options and outcomes in MS.

Methods: We conducted a retrospective review of 23 patients diagnosed with MS at our institute over a period of 13 years (2002–2015).

Results: MS presented mostly as a manifestation of relapsed acute myeloid leukemia, seen in 39% of patients. Skin and subcutaneous soft tissues were the most common sites of anatomic involvement (69.5%). Ninety five percent (n?=?19) were positive for classical myeloid markers with either cytochemical staining (chloracetate-esterase, MPO), flow-cytometry (CD33, CD34, CD13 and CD117), or immunohistochemistry (CD34, CD43, CD68 and lysozyme). Of these, 52% were positive for CD33 (n?=?12), 35% for CD68 (n?=?8), 30% for CD34 (n?=?7), and 26% for lysozyme (n?=?6). Cytogenetic abnormalities were seen in 63% (n?=?12/19) patients on bone-marrow aspirate, with five patients displaying a complex (n?=?3) or monosomal (n?=?2) karyotype. Twenty seven percent patients with a normal karyotype had presence of deleterious mutations (FLT3, ASXL, STAG and JAK2) on further testing with myeloid mutation panel. The Median overall survival (OS) of the entire cohort was 15.9 months (95% CI, 7.4–24.4 months). The OS was significantly better for patients <65 years (24.6 vs. 3.4 months, p?=?0.009) of age, and for those attaining a complete remission (CR) to induction therapy (25.7 vs. 0.8 months, p?Conclusion: Failure to achieve CR with induction therapy, and age >65 years are associated with poor outcomes in MS. Allogeneic stem-cell transplant in first remission appears to be the most effective modality for achieving long-term remissions.  相似文献   
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High frequency micro-ultrasound (µUS) transducers with central frequencies up to 50?MHz facilitate dynamic visualization of patient anatomy with minimal disruption of the surgical work flow. Micro-ultrasound improves spatial resolution over conventional ultrasound imaging from millimeter to micrometer, but compromises depth penetration. This trade-off is sufficient during an open surgery in which the bone is removed and theultrasound probe can be placed into the surgical cavity. By fusing µUS with pre-operative imaging and tracking the ultrasound probe intra-operatively using our optical topographic imaging technology, we can provide dynamic feedback during surgery, thus affecting clinical decision making. We present our initial experience using high-frequency µUS imaging during spinal procedures. Micro-ultrasound images were obtained in five spinal procedures. Medical rationale for use of µUS was provided for each patient. Surgical procedures were performed using the standard clinical practice with bone removal to facilitate real-time ultrasound imaging of the soft tissue. During surgery, the µUS probe was registered to the pre-operative computed tomography and magnetic resonance images. Images obtained comprised five spinal decompression surgeries (four tumor resections, one cystic synovial mass). Micro-ultrasound images obtained during spine surgery delineated exquisite detailing of the spinal anatomy including white matter and gray matter tracts and nerve roots and allowed accurate assessment of the extent of decompression/tumor resection. In conclusion, tracked µUS enables real-time imaging of the surgical cavity, conferring significant qualitative improvement over conventional ultrasound.  相似文献   
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