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BackgroundHeart failure (HF) patients exhibit depression and executive function impairments that contribute to HF mortality. Using specialized magnetic resonance imaging (MRI) analysis procedures, brain changes appear in areas regulating these functions (mammillary bodies, hippocampi, and frontal cortex). However, specialized MRI procedures are not part of standard clinical assessment for HF (which is usually a visual evaluation), and it is unclear whether visual MRI examination can detect changes in these structures.Methods and ResultsUsing brain MRI, we visually examined the mammillary bodies and frontal cortex for global and hippocampi for global and regional tissue changes in 17 HF and 50 control subjects. Significantly global changes emerged in the right mammillary body (HF 1.18 ± 1.13 vs control 0.52 ± 0.74; P = .024), right hippocampus (HF 1.53 ± 0.94 vs control 0.80 ± 0.86; P = .005), and left frontal cortex (HF 1.76 ± 1.03 vs control 1.24 ± 0.77; P = .034). Comparison of the visual method with specialized MRI techniques corroborates right hippocampal and left frontal cortical, but not mammillary body, tissue changes.ConclusionsVisual examination of brain MRI can detect damage in HF in areas regulating depression and executive function, including the right hippocampus and left frontal cortex. Visual MRI assessment in HF may facilitate evaluation of injury to these structures and the assessment of the impact of potential treatments for this damage.  相似文献   
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Background

Fine-needle aspiration (FNA) of adrenals is needed in patients with pyrexia of unknown origin (PUO) and adrenal enlargement in absence of other diagnostic clues. Adrenals are easily accessible by endoscopic ultrasound (EUS) due to proximity; however, there is no systemic study available on FNA of adrenals in patients with PUO. The aim of this study was to evaluate the diagnostic yield and safety of EUS-FNA of enlarged adrenal in patients with PUO.

Methods

Data was analyzed from October 2010 to September 2016 at a single tertiary care center in northern India. EUS-FNA of enlarged adrenals was done in 52 patients for the etiological diagnosis of PUO in whom a definitive diagnosis could not be made with other means.

Results

The mean age was 48±14 years; 36 were males and 16 were females. EUS-FNA was done from the left adrenal in 50 patients and from the right sample in 2 patients. A technical success was achieved in 100% cases. The 19-G needle was used in the majority (75%) to the presence of necrotic areas in adrenals; median numbers of passes were 2. The cytopathological diagnoses were tuberculosis (n?=?36), histoplasmosis (n?=?13), lymphoma (n?=?2), and metastasis from undiagnosed neuroendocrine tumor of lung (n?=?1). Thus, a diagnosis could be made in 52/52 (100%) patients. None of the patients had any procedure-related complications.

Conclusions

EUS-FNA is a safe and effective method for evaluating etiology of PUO in patients with adrenal enlargement.
  相似文献   
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The human immunodeficiency virus type 1 (HIV-1) rev exons 1 and 2 sequences were analyzed from six mother-infant pairs following perinatal transmission. The rev open reading frame was maintained with a frequency of 93.96% in six mother-infant pairs' sequences. There was a low degree of viral heterogeneity and estimates of genetic diversity in mother-infant pairs' rev sequences. However, the distances of rev sequences between epidemiologically unlinked individuals were greater than in epidemiologically linked mother-infant pairs. Furthermore, phylogenetic parameters revealed that the epidemiologically linked mother-infant pairs were closer evolutionarily to each other as compared with epidemiologically unlinked mother-infant pairs. Both mothers and infants were under positive selection pressure as determined by the ratios of nonsynonymous to synonymous substitutions. The functional domains required for Rev activity, including nuclear export of RNA, RNA binding domain, and nuclear import signals, were conserved in all mother-infant pairs' sequences. The conservation of functional domains of rev and a low degree of heterogeneity following vertical transmission are consistent with an indispensable role of rev in the HIV-1 life cycle.  相似文献   
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This study examined the feasibility and potential clinical utility of magnetic resonance imaging (MRI) evaluation of myocardial perfusion (first-pass contrast enhancement) and viability (myocardial delayed enhancement) in 30 patients with congenital and acquired pediatric heart disease. Good agreement was found between MRI evaluation of myocardial perfusion and viability and analysis of segmental wall motion as well as coronary angiography (n = 10) and single photon emission computed tomography (n = 6).  相似文献   
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BackgroundComputed Tomography (CT) Pulmonary Angiography is the most commonly used diagnostic study for acute pulmonary embolism (PE). Echocardiogram (ECHO) is also used for risk stratification in acute PE, however the diagnostic performance of CT versus ECHO for risk stratification remains unclear.MethodsCT and ECHO right ventricle (RV) and left ventricle (LV) diameters were measured in a retrospective cohort of patients with acute PE. RV:LV diameter ratios were calculated and correlation between CT and ECHO RV:LV ratio was assessed. Sensitivity and specificity for the composite adverse events endpoint of mortality, respiratory failure requiring intubation, cardiac arrest, or shock requiring vasopressors within 30 days of admission were assessed for CT or ECHO derived RV:LV ratio alone and in combination with biomarkers (troponin or B-type natriuretic peptide).ResultsA total of 74 subjects met the inclusion criteria and had a mean age of 62±18 years. The proportion of patients with RV:LV >1 was similar when comparing CT (37.8%) versus ECHO (33.8%) (P = 0.61). A statistically significant correlation was found between CT derived and ECHO derived RV:LV diameter ratio (r = 0.832, P < 0.001). The sensitivity and specificity to predict 30-day composite adverse events for CT versus ECHO derived RV:LV diameter ratio >1 together with positive biomarker status was similar with sensitivity and specificity of 87% and 41% versus 87% and 42%, respectively.ConclusionsIn patients with acute PE, CT and ECHO RV:LV diameter ratio correlate well and identify similar proportion of PE patients at risk for early adverse events. These findings may streamline risk stratification of patients with acute PE.  相似文献   
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