BackgroundHemophagocytic lymphohistiocytosis (HLH) is a relatively rare but life-threatening disease with confusing clinical manifestations, rapidly deteriorating health, high morbidity and mortality.MethodsTo improve the recognition as well as understanding of this disorder, we analyzed clinical characteristics and prognostic factors from 85 adult patients diagnosed with HLH in our hospital from April 2005 to June 2014.ResultsPatients with HLH displayed variable clinical markers across a wide spectrum. These included fever and hyperferritinemia (100%), elevated lactate dehydrogenase (LDH) (98.8%), two or three cytopenia (92.2%), splenomegaly (72.9%), hypofibrinogenemia (69.4%), hypertriglyceridemia (64.7%), hemophagocytosis (51.7%), and hepatomegaly (24.7%). Patients with active Epstien-Barr Virus (EBV) infection had a median overall survival (OS) of 65 days. Those displaying malignancy had very poor survival (median OS: 40 days). However, patients in rheumatic and non-EBV infection groups had relatively superior prognosis (not reached). Univariate analysis showed that Fibrinogen (Fbg) <1.5 g/L, platelet number (PLT) <40 × 109/L and LDH ≥1000 U/L were factors that negatively affected survival (P = 0.004, 0.000, 0.002). Multivariate analysis showed that PLT <40 × 109/L was the independent adverse factor (HR = 0.350, 95% CI: 0.145-0.844, P = 0.019).ConclusionsHLH had very complex clinical manifestations and high death rate. Patients with active EBV infection, malignancy, Fbg <1.5 g/L, PLT <40 × 109/L and LDH ≥1000 U/L had high risk of death as well as inferior survival, and these patients require systemic targeted treatments as early as possible.

To identify the clinical features of lymphoma-associated hemophagocytic syndrome (LAHS), we retrospectively analyzed the clinical characteristics, laboratory findings and survival data of 16 LAHS patients from 69 adult hemophagocytic syndrome (HPS) patients. The results showed that the most common clinical manifestations and laboratory parameters were fever (100%), ferritin ≥ 500 g/L (100%), peripheral cytopenia in two or more lineages (100%), fibrinogen (Fbg) < 1.5 g/L (93.8%) and splenomegaly (81.3%) in LAHS patients. The percentages of patients with Fbg < 1.5 g/L, PLT < 40 × 10(9)/L and LDH ≥ 1,000 U/L in the LAHS group were significantly higher than those in non-LAHS patients (P = 0.010, 0.000, and 0.001, respectively). Survival analysis showed that HLH patients with rheumatological reasons had better prognosis (OS; median not reached), followed by patients in the infection group (350 days) and those with unexplained causes (140 days). LAHS had the worst prognosis (only 37 days). The symptoms of LAHS patients are usually confused with other HPS. Patients with LAHS had higher probabilities to have Fbg < 1.5 g/L, PLT < 40 × 10(9)/L, LDH ≥ 1,000 U/L and poor prognosis, so early diagnosis and systemic treatments are required.

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A magnetization transfer (MT)-prepared echo-planar imaging (EPI) pulse sequence was developed to study motor cortex activation, using a finger tapping paradigm. MT weighting resulted in a reduction of both the activated area and, in the majority of activated pixels, the functional MRI signal, regardless of the correlation coefficient threshold used in generating the activation map. The magnetization transfer ratio (MTR) was higher during task activation than during rest. Because the MT effect is strongly tissue-dependent, these results support the hypothesis that incorporation of MT into functional MRI will help to understand the origin of the functional MRI signal.

A multishot partial-k-space EPI technique is presented and validated by fMRI at high spatial resolution. High-resolution phase maps corrected by phase-encoded reference scans have less off-resonance effects. Phantom studies demonstrate that this method can substantially improve partial-k-space EPI image formation. BOLD fMRI at submillimeter spatial resolution (156 ؋ 156 ؋ 2000 m 3 , 0.049 l) was achieved in a rat whisker barrel stimulation model using this technique. The study included eight rats, five of which were administered an intravascular contrast agent (monocrystalline iron oxide nanocolloid (MION)) after the BOLD experiments. In two rats the highest BOLD responses were in the deep layers (IV-VI), and in six rats the highest responses were on the surface and in the deep cortical layers. Most of the pixels that exhibited high BOLD responses had high blood volume weightings. Blood oxygenation level-dependent (BOLD) contrast is commonly used in functional magnetic resonance imaging (fMRI). Theoretical analyses (1-4) and experimental data (5-9) have demonstrated that the sensitivity and specificity of the BOLD response increase as the magnetic field strength increases. However, T* 2 of brain tissues decreases as the field strength increases. For example, T* 2 of human brain gray matter is about 40 ms at 3 Tesla (8), and 25 ms at 7 T (10). This short T* 2 imposes inherent limitations on the resolution of echo-planar imaging (EPI), because of the increased point spread function (PSF) along the y-axis (phase-encoding direction) (11). For multishot EPI acquisitions, short T* 2 values constrain the number of k-space lines that can be acquired per shot. For example, for a four-shot GR-EPI using full k-space with a matrix size of 256 ϫ 256, 166 kHz data acquisition bandwidth, and a local gradient coil with a gradient ramp time of 96 s, the minimum echo time (TE) is about 65 ms. The TE is even longer when gradient coils with a lower slew rate, or narrower data acquisition bandwidths are used. In order to achieve a better signal-to-noise ratio (SNR), more shots must be employed, which compromises temporal resolution.An alternative way to achieve high resolution in fMRI is to employ half-k-space data acquisition. Half-k-space EPI allows data to be acquired in less time than that required by full-k-space EPI by a factor of ϳ1/2 for any desired matrix, and the TE is shorter because the central k-space lines are collected first. In fMRI, short data acquisition times and TEs are desirable because they enable high spatial/temporal resolution imaging without compromising the SNR (12). Additionally, short data acquisition times can reduce the image distortions that are typically found in EPI, and shorter TEs reduce signal dropout in regions with strong susceptibilities.Another benefit of half-k-space data acquisition is the narrower PSF, which is critically important in high-resolution fMRI. Jesmanowicz et al. (13) demonstrated that the y-axis PSF arising from T* 2 decay in full-k-space acquisition is 3 1/2 times wider than...