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81.
BackgroundIntrathoracic involvement with lymphomas is common and manifests lymphadenopathy as well as a wide spectrum of imaging abnormalities in the lungs. Intravascular large B-cell lymphoma (IVLBCL) is a rare extranodal subtype of large B-cell lymphoma that typically involves small blood vessels and is difficult to detect.MethodsUsing a computer-assisted search, we identified patients with histopathologically proven IVLBCL in the lungs at Mayo Clinic from 2001 through 2018. Medical records, imaging studies, and pathologic specimens were reviewed.ResultsA total of 5 patients were diagnosed with a median age at diagnosis of 68 years (range, 44-73); 4 patients were male. The diagnosis of IVLBCL was achieved by surgical lung biopsy in 3 and at autopsy in 2. At presentation, all 5 patients had dyspnea and systemic symptoms including fever, fatigue, night sweats, and/or weight loss. Chest radiography and computed tomography (CT) failed to demonstrate the diffuse infiltrative process; positron emission tomography (PET) scan performed in 2 patients did not show fluorodeoxyglucose (FDG) uptake in the lungs. Pulmonary function tests obtained in 3 patients showed reduced diffusing capacity in all; transthoracic echocardiography yielded evidence of pulmonary hypertension in 2 of 4 patients. All 3 patients diagnosed antemortem underwent chemotherapy with 1 patient remaining alive at 4 years after diagnosis.ConclusionsIVLBCL is difficult to diagnose given variable and nonspecific clinical presentations. Microvascular disease processes such as IVLBCL should be kept in mind in cases of undiagnosed progressive dyspnea accompanied by systemic symptoms even when imaging studies are unrevealing.  相似文献   
82.
Rationale:Veno-occlusive disease (VOD) is characterized by painful hepatomegaly, ascites, weight gain, and jaundice with nonthrombotic, fibrous obliteration of the centrilobular hepatic veins. VOD after liver transplantation is a rare complication, with an incidence of approximately 2%; however, it can be life-threatening in severe cases. The precise etiology and mechanism of VOD after liver transplantation remains unclear. Acute cellular rejection, antibody-mediated rejection, and treatment with tacrolimus or azathioprine may be associated with the development of VOD after liver transplantation. Additionally, the optimal treatment of VOD after liver transplantation has not yet been established and focuses on supportive care. Defibrotide is an anti-ischemic and antithrombotic drug with no systemic anticoagulant effects. Moreover, only a few reports have investigated the use of defibrotide for VOD after liver transplantation, which has shown promising results.Patient concerns:A 39-year-old woman with primary biliary cholangitis underwent living-donor liver transplantation at our center. She experienced right upper quadrant pain with increased ascites, pleural effusion, and weight gain on postoperative day 14.Diagnoses:Imaging and pathological tests showed no evidence of rejection or vessel complications. VOD was diagnosed clinically based on the findings of weight gain, ascites, jaundice, and pathological biopsy.Interventions:Defibrotid, 25 mg/kg/day, was administered intravenously for 21 days.Outcomes:She showed complete clinical resolution of the VOD.Lessons:Herein, we report a case of successful defibrotide treatment of VOD after living-donor liver transplantation.  相似文献   
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BACKGROUND: Cardiac resynchronization therapy (CRT) for congestive heart failure patients with delayed left ventricular (LV) conduction is clinically beneficial in approximately 70% of patients. Unresolved issues include patient selection, lead placement, and efficacy of LV pacing alone. Being an electrical approach, detailed electrical information during CRT is critical to resolving these issues. However, electrical data from patients have been limited because of the requirement for invasive mapping. OBJECTIVES: The purpose of this study was to provide observations and insights on the variable electrophysiologic responses of the heart to CRT using electrocardiographic imaging (ECGI). METHODS: ECGI is a novel modality for noninvasive epicardial mapping. ECGI was conducted in eight patients undergoing CRT during native rhythm and various pacing modes. RESULTS: In native rhythm (six patients), ventricular activation was heterogeneous, with latest activation in the lateral LV base in three patients and in the anterolateral, midlateral, or inferior LV in the remainder of patients. Anterior LV was susceptible to block and slow conduction. Right ventricular pacing improved electrical synchrony in two of six patients. LV pacing in three of four patients involved fusion with intrinsic excitation resulting in electrical resynchronization similar to biventricular pacing. Although generally electrical synchrony improved significantly with biventricular pacing, it was not always accompanied by clinical benefit. CONCLUSION: Results suggest that (1) when accompanied by fusion, LV pacing alone can be as effective as biventricular pacing for electrical resynchronization; (2) right ventricular pacing is not effective for resynchronization; and (3) efficacy of CRT depends strongly on the patient-specific electrophysiologic substrate.  相似文献   
85.
Erythropoietin (EPO) induces erythropoiesis in vitro as well as in vivo, and the process of erythroid differentiation has been explored phenotypically and morphologically. However, morphological analysis of in vitro erythropoiesis of human hematopoietic progenitor cells at the ultrastructural level has not been reported before. In the present study, we have traced the ultrastructural changes of erythroid differentiation during ex vivo expansion of human cord blood (CB) CD34(+) cells in the presence of EPO by electron microscopy (EM), along with concurrent phenotypic analysis. CD34(+) cells purified from ten CBs by immunomagnetic selection were cultured in serum-free essential media in the presence of a combination of the several cytokines including EPO, thrombopoietin, flt3-ligand (FL), stem cell factor (SCF), granulocyte colony-stimulating factor, interleukin (IL)-3 and/or IL-11. Phenotypic analysis was performed by flow cytometric analysis for erythroid markers, including glycophorin C (GPC), Kell-related, glycophorin A (GPA), band 3, Lu(b), and RhD. Ultrastructural analysis was performed by electron-microscopic examination of the cultured cells stained with uranyl acetate and lead citrate. Phenotypic analysis revealed that in the absence of EPO, genuine erythroid fraction expressing the typical pattern of erythroid markers did not appear. The order of the above markers expressed in the cultured cells in the presence of EPO was GPC, Kell-related, GPA, band 3, Lu(b), and RhD, irrespective of the type of cytokine added. Of the cytokines used in combination with EPO, FL + IL-3 was the most efficient in inducing erythroid differentiation, which was followed by SCF + IL-3. EM examination demonstrated complete process of erythroid development from pronormoblasts to reticulocytes with nuclei having been extruded and mature erythrocytes. These results suggest that morphologically intact erythrocytes could be produced by ex vivo expansion of CB CD34(+) cells using EPO.  相似文献   
86.
The objectives of this study were to evaluate dosimetric quality and acute toxicity of volumetric-modulated arc therapy (VMAT) and daily image guidance in high-risk prostate cancer patients. A total of 100 consecutive high-risk prostate cancer patients treated with definitive VMAT with prophylactic whole-pelvic radiotherapy (WPRT) were enrolled. All patients were treated with a double-arc VMAT plan delivering 52 Gy to the prostate planning target volume (PTV), while simultaneously delivering 46.8 Gy to the pelvic nodal PTV in 26 fractions, followed by a single-arc VMAT plan delivering 26 Gy to the prostate PTV in 13 fractions. Image-guided RT was performed with daily cone-beam computed tomography. Dose–volume parameters for the PTV and the organs at risk (OARs), total number of monitor units (MUs) and treatment time were evaluated. Acute toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.0. All dosimetric parameters met the present plan acceptance criteria. Mean MU and treatment time were 471 and 146 s for double-arc VMAT, respectively, and were 520 and 76 s for single-arc VMAT, respectively. No Grade 3 or higher acute toxicity was reported. Acute Grade 2 proctitis, diarrhea, and genitourinary toxicity occurred in 12 patients (12%), 6 patients (6%) and 13 patients (13%), respectively. The present study demonstrated that VMAT for WPRT in prostate cancer results in favorable PTV coverage and OAR sparing with short treatment time and an acceptable rate of acute toxicity. These findings support the use of VMAT for delivering WPRT to high-risk prostate cancer patients.  相似文献   
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88.

Background

Neutrophil-to-lymphocyte ratio (NLR) has been used as a predictive marker for various conditions. However, there are no previous studies about NLR as a prognostic marker for acute infarction.

Objective

To evaluate the potential utility of NLR as a predictor of acute infarction in acute vertigo patients without neurologic and computed tomography (CT) abnormalities.

Methods

We conducted a prospective, observational study in the Emergency Department (ED) between January 2015 and December 2016. All patients underwent physical examination, laboratory tests, CT, and magnetic resonance imaging (MRI). Results of the initial and follow-up MRI with clinical progress note were considered as the reference standard. Statistically, multivariate logistic regression analysis and receiver operating characteristic (ROC) curve were used.

Results

Thirty-five (25.9%) patients were diagnosed with acute infarction and 100 (74.1%) patients were diagnosed with peripheral vertigo. Horizontal nystagmus (p = 0.03; odds ratio 0.22) and NLR (p = 0.03; odds ratio 5.4) were significant factors for the differential diagnosis of acute infarction and peripheral vertigo. NLR > 2.8 showed the greatest area under the ROC curve (AUC; 0.819), optimal sensitivity (85.7%), and specificity (78.0%). NLR > 1.4 showed the highest sensitivity (97.1%) and relatively low specificity (41%). The absence of horizontal nystagmus increased the specificity (81.0%) and AUC (0.844).

Conclusions

A combination of NLR > 2.8 and the absence of horizontal nystagmus is sufficiently specific for acute infarction in an ED patient with acute vertigo; thus, further testing with MRI is indicated. NLR < 2.8 by itself or combined with the presence of horizontal nystagmus is not sufficiently sensitive to rule out the need for further testing.  相似文献   
89.
BACKGROUND/OBJECTIVESFood insecurity has been suggested as being negatively associated with healthy behaviors and health status. This study was performed to identify the associations between food insecurity and healthy behaviors among Korean adults.SUBJECTS/METHODSThe data used were the 2011 Community Health Survey, cross-sectional representative samples of 253 communities in Korea. Food insecurity was defined as when participants reported that their family sometimes or often did not get enough food to eat in the past year. Healthy behaviors were considered as non-smoking, non-high risk drinking, participation in physical activities, eating a regular breakfast, and maintaining a normal weight. Multiple logistic regression and multinomial logistic regression analyses were used to identify the association between food insecurity and healthy behaviors.RESULTSThe prevalence of food insecurity was 4.4% (men 3.9%, women 4.9%). Men with food insecurity had lower odds ratios (ORs) for non-smoking, 0.75 (95% CI: 0.68-0.82), participation in physical activities, 0.82 (95% CI: 0.76-0.90), and eating a regular breakfast, 0.66 (95% CI: 0.59-0.74), whereas they had a higher OR for maintaining a normal weight, 1.19 (95% CI: 1.09-1.30), than men with food security. Women with food insecurity had lower ORs for non-smoking, 0.77 (95% CI: 0.66-0.89), and eating a regular breakfast, 0.79 (95% CI: 0.72-0.88). For men, ORs for obesity were 0.78 (95% CI: 0.70-0.87) for overweight and 0.56 (95% CI: 0.39-0.82) for mild obesity. For women, the OR for moderate obesity was 2.04 (95% CI: 1.14-3.63) as compared with normal weight.CONCLUSIONSFood insecurity has a different impact on healthy behaviors. Provision of coping strategies for food insecurity might be critical to improve healthy behaviors among the population.  相似文献   
90.
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