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Journal of Artificial Organs - Veno-venous extracorporeal membrane oxygenation (ECMO) is typically instituted in severe respiratory failure, defined by Lung Injury Score, and caused either by...  相似文献   
964.
Objective:To compare diffusion-weighted images (DWI) acquired using single-shot echo-planar imaging (ss-EPI) and multiplexed sensitivity encoding (MUSE) in breast cancer.Methods20 females with pathologically confirmed breast cancer (age 51 ± 12 years) were imaged with ss-EPI-DWI and MUSE-DWI. ADC, normalised ADC (nADC), blur and distortion metrics and qualitative image quality scores were compared. The Crété-Roffet and Mattes mutual information metrics were used to evaluate blurring and distortion, respectively. In a breast phantom, six permutations of MUSE-DWI with varying parallel acceleration factor and number of shots were compared. Differences in ADC and nADC were compared using the coefficient of variation in the phantom and a paired t-test in patients. Differences in blur, distortion and qualitative metrics were analysed using a Wilcoxon signed-rank test.Results:There was a low coefficient of variation (<2%) in ADC between ss-EPI-DWI and all MUSE-DWI permutations acquired using the phantom. 22 malignant and three benign lesions were identified in 20 patients. ADC values measured using MUSE were significantly lower compared to ss-EPI for malignant but not benign lesions (p < 0.001, p = 0.21). nADC values were not significantly different (p = 0.62, p = 0.28). Blurring and distortion improved with number of shots and acceleration factor, and significantly improved with MUSE in patients (p < 0.001, p = 0.002). Qualitatively, image quality improved using MUSE.Conclusion:MUSE improves the image quality of breast DWI compared to ss-EPI.Advances in knowledge:MUSE-DWI has superior image quality and reduced blurring and distortion compared to ss-EPI-DWI in breast cancer.  相似文献   
965.
Objective:To assess accuracy of and interobserver agreement on multiparametric MR findings to distinguish uterine leiomyoma (LM) from uterine leiomyosarcoma (LMS) and soft tissue tumour of unknown malignant potential.Methods:Inclusion criteria: All females over 18 years with least one uterine mass measuring 5 cm or more in at least one of the three standard orthogonal dimensions on MR with histopathological confirmation of LM, LMS, or soft tissue tumour of unknown malignant potential (STUMP) in the 3 months following MR. Patients with LMS were drawn from a larger cohort being assessed for MR-guided focussed ultrasound (MRgFUS) suitability. Image evaluation: Assessed variables were: lesion margin, margin definition, T2 signal homogeneity, >50% of lesion with T2 signal brighter than myometrium, haemorrhage, restricted diffusion, contrast enhancement (CE), CE pattern, local lymphadenopathy and ascites.Results:32 LM, 10 LMS and 1 STUMP were evaluated. Ill-defined (p-value = 0.0003–0.0004) or irregular (p = 0.003–0.004) lesion margin, T2 hyperintensity >50% (p = 0.001–0.004), and peripheral CE (p = 0.02–0.05) were significantly more common in LMS/STUMP than LM for both radiologists. 10/11 (Reader 2) and 11/11 (Reader 1) LMS/STUMP displayed restricted diffusion but so did 63–80% of LM. Agreement was greatest for margin characteristics (κ = 0.73–0.81).Conclusion:Irregular/ill-defined lesion margin best distinguished LMS/STUMP from LM with good interrater reliability.Advances in knowledge:Assessment of agreement regarding MR parameters distinguishing LM from LMS and STUMP has not previously been undertaken in a cohort including a large number of patients with LMS. This will help inform evaluation of females considering minimally invasive LM treatment.  相似文献   
966.
Kohlschütter–Tönz syndrome (KTS) is a rare autosomal recessive disorder characterized by amelogenesis imperfecta, psychomotor delay or regression and seizures starting early in childhood. KTS was established as a distinct clinical entity after the first report by Kohlschütter in 1974, and to date, only a total of 20 pedigrees have been reported. The genetic etiology of KTS remained elusive until recently when mutations in ROGDI were independently identified in three unrelated families and in five likely related Druze families. Herein, we report a clinical and genetic study of 10 KTS families. By using a combination of whole exome sequencing, linkage analysis, and Sanger sequencing, we identify novel homozygous or compound heterozygous ROGDI mutations in five families, all presenting with a typical KTS phenotype. The other families, mostly presenting with additional atypical features, were negative for ROGDI mutations, suggesting genetic heterogeneity of atypical forms of the disease.  相似文献   
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BackgroundAspirin prevents coronary thrombosis and is used extensively in cardiovascular prophylaxis. However, patients with a prior history of an aspirin “reaction” are routinely denied this medication.ObjectiveTo characterize the clinical presentation of a cohort of patients with coronary artery disease (CAD) and aspirin reactions.MethodsBetween 2009 and 2012, using a retrospective computer analysis, information was collected on all patients within a county-wide health care system presenting with CAD and a prior history of aspirin reactions.ResultsOf 9,565 patients with CAD, a prior history of aspirin reactions was recorded in 142 patients. Of these 142 patients, 30 (21%) had histories compatible with cutaneous and/or respiratory reactions. The other patients described adverse effects to aspirin, mostly gastrointestinal intolerance and bleeding. Aspirin-induced anaphylaxis was recorded in patients but may have been misdiagnosed, describing instead respiratory hypersensitivity reactions. Of the 142 patients, only 34 (24%) were receiving daily cardiovascular prophylaxis with aspirin. Of 108 patients not receiving aspirin, 25 (17.6%) were prescribed clopidogrel.ConclusionHistories of aspirin reactions in patients with CAD are uncommon, occurring in only 1.5% of our study population. The 21% of patients with histories compatible with aspirin hypersensitivities can be challenged and, if the results are positive, successfully desensitized. Moreover, almost all patients with gastric intolerance to aspirin can be treated with aspirin and a proton pump inhibitor. However, both approaches, which result in restoration of cardiovascular prophylaxis, were seriously underused in our study population.  相似文献   
969.
Amyloid myopathy associated with a plasma cell dyscrasia is a rare cause of muscle hypertrophy. It can be a challenging diagnosis, since pathological findings are often elusive. In addition, the mechanism by which immunoglobulin light-chain deposition stimulates muscle overgrowth remains poorly understood. We present a 53-year old female with a 10-year history of progressive generalized muscle overgrowth. Congo-red staining and immunohistochemistry revealed perivascular lambda light chain amyloid deposits, apparent only in a second muscle biopsy. The numbers of central nuclei and satellite cells were increased, suggesting enhanced muscle progenitor cell formation. Despite the chronicity of the light chain disease, the patient showed complete resolution of hematologic findings and significant improvement of her muscle symptoms following autologous bone marrow transplantation. This case highlights the importance of early diagnosis and therapy for this treatable cause of a chronic myopathy with muscle hypertrophy.  相似文献   
970.
Urinary tract infections (UTI), which are mostly caused by Escherichia coli, are an important public health problem worldwide. Although men experience diverse UTI syndromes, there have been relatively few molecular-epidemiological studies of UTI pathogenesis in men. We studied the distribution of 22 E. coli virulence factor (VF) genes, major phylogenetic groups, sequence type ST131, and UTI-associated O antigens among 101 pyelonephritis, 153 cystitis and 135 fecal healthy control E. coli isolates from men aged 30–70 years in a regional area of NSW, Australia. Overall, the studied traits exhibited a prevalence gradient across these groups, highest in pyelonephritis, intermediate in cystitis, and lowest among fecal isolates. Differences in virulence gene prevalence between cystitis and pyelonephritis isolates were limited to eight genes. The UTI-associated O antigens were also distributed widely, but types O6, O25 and O75 were significantly associated with pyelonephritis. The ST131 clonal group, which accounted for 13% of isolates overall (22% of group B2 isolates), likewise exhibited a significant descending prevalence gradient from pyelonephritis (36%), through cystitis (8%), to fecal (0%) isolates. These findings contribute to better understanding of the pathogenesis of UTIs in men and identify specific VF genes and O types, and a prominent clonal group (ST131), as being important in UTI pathogenesis in this population.  相似文献   
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