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Understanding why persons with human immunodeficiency virus (HIV) have accelerated atherosclerosis and its sequelae, including coronary artery disease (CAD) and myocardial infarction, is necessary to provide appropriate care to a large and aging population with HIV. In this review, we delineate the diverse pathophysiologies underlying HIV-associated CAD and discuss how these are implicated in the clinical manifestations of CAD among persons with HIV. Several factors contribute to HIV-associated CAD, with chronic inflammation and immune activation likely representing the primary drivers. Increased monocyte activation, inflammation, and hyperlipidemia present in chronic HIV infection also mirror the pathophysiology of plaque rupture. Furthermore, mechanisms central to plaque erosion, such as activation of toll-like receptor 2 and formation of neutrophil extracellular traps, are also abundant in HIV. In addition to inflammation and immune activation in general, persons with HIV have a higher prevalence than uninfected persons of traditional cardiovascular risk factors, including dyslipidemia, hypertension, insulin resistance, and tobacco use. Antiretroviral therapies, although clearly necessary for HIV treatment and survival, have had varied effects on CAD, but newer generation regimens have reduced cardiovascular toxicities. From a clinical standpoint, this mix of risk factors is implicated in earlier CAD among persons with HIV than uninfected persons; whether the distribution and underlying plaque content of CAD for persons with HIV differs considerably from uninfected persons has not been definitively studied. Furthermore, the role of cardiovascular risk estimators in HIV remains unclear, as does the role of traditional and emerging therapies; no trials of CAD therapies powered to detect clinical events have been completed among persons with HIV.  相似文献   
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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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PURPOSE: To monitor tumor blood flow noninvasively during photodynamic therapy (PDT) and to correlate flow responses with therapeutic efficacy. EXPERIMENTAL DESIGN: Diffuse correlation spectroscopy (DCS) was used to measure blood flow continuously in radiation-induced fibrosarcoma murine tumors during Photofrin (5 mg/kg)/PDT (75 mW/cm2, 135 J/cm2). Relative blood flow (rBF; i.e., normalized to preillumination values) was compared with tumor perfusion as determined by power Doppler ultrasound and was correlated with treatment durability, defined as the time of tumor growth to a volume of 400 mm3. Broadband diffuse reflectance spectroscopy concurrently quantified tumor hemoglobin oxygen saturation (SO2). RESULTS: DCS and power Doppler ultrasound measured similar flow decreases in animals treated with identical protocols. DCS measurement of rBF during PDT revealed a series of PDT-induced peaks and declines dominated by an initial steep increase (average +/- SE: 168.1 +/- 39.5%) and subsequent decrease (59.2 +/- 29.1%). The duration (interval time; range, 2.2-15.6 minutes) and slope (flow reduction rate; range, 4.4 -45.8% minute(-1)) of the decrease correlated significantly (P = 0.0001 and 0.0002, r2= 0.79 and 0.67, respectively) with treatment durability. A positive, significant (P = 0.016, r2= 0.50) association between interval time and time-to-400 mm3 was also detected in animals with depressed pre-PDT blood flow due to hydralazine administration. At 3 hours after PDT, rBF and SO2 were predictive (P < or = 0.015) of treatment durability. CONCLUSION: These data suggest a role for DCS in real-time monitoring of PDT vascular response as an indicator of treatment efficacy.  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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