Characterization of Responder Profiles for Cardiac Resynchronization Therapy through Unsupervised Clustering of Clinical and Strain Data

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Prediction and monitoring of treatment effect using T1-weighted dynamic contrast-enhanced magnetic resonance imaging in colorectal liver metastases: Potential of whole tumour ROI and selective ROI analysis

Purpose

To evaluate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for prediction and early monitoring of treatment in colorectal liver metastases.

Materials and methods

Ten patients were included. Baseline and follow-up DCE-MRI examinations were evaluated by whole tumour and selected ROI placements calculating Kep-values. Selective ROIs, concentric-like and hot spot, were drawn on early arterial phase images. Monitoring of treatment was performed comparing RECIST1.1 criteria with whole tumour and selected ROI placement. To evaluate treatment effect between responders and non-responders, independent samples t-test was used on Kep-values.

Results

In each patient largest lesion was evaluated totalling 10 target lesions. At baseline, for whole tumour ROI placements mean Kep-values in responders were significantly higher than mean Kep-values in non-responders (t = 7.481, p < 0.001). Selective ROI placement comparison of mean Kep-values at baseline and after 6 weeks of treatment (first follow-up measurement) showed significant decrease in responding patients (t = 4.706, p = 0.003) whereas increase in Kep-values in non-responding patients was not statistically significant.

Conclusion

This preliminary study shows that baseline Kep for whole tumour ROI is a predictor for treatment outcome. Decrease of Kep using selective ROIs allows early identification of response after 6 weeks of treatment.     

烟煤快速加氢热解研究——半焦,挥发分和焦油等生成行为的考察

烟煤快速加氢热解，除获取轻质烃和甲烷等气，液产品外，还得到半焦，焦油和水，半焦中残留挥发分。在氢气氛中快速热解生成半焦中的挥发分低于氮气氛，残留挥发分的多少是衡量快速热解反应程度的标志。加氢热解后生成半焦的堆密度仅为原煤的１／３．５，活性半焦直接加氢反应生成甲烷是引起半焦密度减小的主要原因之一。轻质烃产率与焦油生成量有关，焦油加氢二次反应是轻质烃生成的主要途径。氢气氛中热解生成的水多于氮气氛，气相     

Flash Visual Evoked Potentials of Various Derivations in Dementia of the Alzheimer Type and Vascular Dementia

Background : Recently, evoked potentials have been used for objective monitoring of the cortical function in dementia. The aim of this study was to distinguish dementia of the Alzheimer type (DAT) from vascular dementia (VaD) using flash visual evoked potentials of various derivations.
Methods : A total of 70 patients consulting Tachikawa Medical Center Kashiwazaki Kosei Hospital were divided into four groups, normal adult (29.5 ± 8.5 years, n=16), normal elderly (77.2 ± 4.7 years, n=17), VaD (81.1 ± 8.1 years, n=17) and DAT (77.4 ± 5.6 years, n=20). Red flash stimulation was provided by a pair of goggles. Visual evoked potentials (VEPs) to flash were recorded in accordance with the International 10–20 Electrode System.
Results : The latencies of N130 and P190 of frontal and central derivations were significantly reduced in DAT compared with all other groups (p<0.05). The N130 and P190 latencies were markedly delayed in the normal elderly group compared with the normal adult group (p<0.05). The P3 (P100) latency of occipital derivation was significantly delayed in normal elderly, VaD and DAT groups compared with the normal adult group (p<0.05). In the DAT group, the P190 latency was shortened at central and frontal derivations compared with that at occipital derivation (p<0.05).
Conclusions : The N130 and P190 latencies decreased at frontal and central derivations in DAT. While the reason is still unclear, dysfunction in the central visual system induced by the degeneration of neuronal populations in DAT may cause the apparently reduced latency. Flash VEPs of frontal and central derivations may be useful for the differential diagnosis of DAT from VaD.     

Calculation of signal intensities in hybrid sequences for fast NMR imaging

A number of techniques that recently have been used for fast NMR-imaging are based on a hybrid sequence of echo planar imaging (EPI) and FLASH imaging: after each NMR excitation several k-space lines are measured. The complete k-space is covered by performance of several excitations. It has been observed that there is usually an optimal hybrid sequence that maximizes the signal-to-noise ratio. In this work, a method is presented that allows a determination of the optimal sequence as a function of the relaxation times T₁ and T₂^*.     

手热辊筒挤压伤72例治疗总结

本文收集1980年1月至1995年12月间治疗手热辊筒挤压伤72例，均使用皮瓣修复．下腹部皮瓣26块，髂腰部皮瓣30块，前臂岛状皮瓣3块，侧胸部皮管11个．文章讨论了手热辊筒挤压伤的特点及分类，手术方法的选择，髂腰部皮瓣是修复手热辊筒挤压伤最理想的供瓣区．     

Visual Functions and TraceElement Metabolism in Tobacco-toxic Optic Neuropathy

Visual functions and nutrition metabolic characteristics werestudied in 8 subjects(16 eyes)with tobacco-toxic optic neuropathy(TTON).Their visual functions tested by psychophysical and electrophysiologicmethods showed that:1.central vision diminished in 16 eyes,2.dyschromatopsias were found in 14 tested eyes,3.bilateral symmetricalcentral or cecocentral scotomas were the visual field characteristics in allcases,4.PVEP were severe abnormal in 3 spatial frequencies in all cases and56.3% of 15‘ checkboard ...     

A comparison of the effects of mixed static and dynamic work with mainly dynamic work in hot conditions

Summary Current physiological criteria for limiting work in hot conditions are frequently based on responses to mainly dynamic work (eg treadmill walking). Their applicability to industrial situations containing mixed static and dynamic work is questioned, since the physiological responses to static work are different from those of dynamic work. Each of eight subjects attempted a one hour uphill treadmill walk (mainly dynamic work), and an uphill treadmill walk whilst intermittently carrying a 20 kg weight in the arms (mixed static and dynamic work). The external work rates in the two conditions were equal, effected by lowering the treadmill gradient in the loaded condition. Experiments were conducted in a hot climate (33‡ C dry bulb, 25‡ C wet bulb). Oxygen consumption, minute ventilation, sweat rate and rated perceived exertion were all significantly higher (p<0.001) for the mixed static and dynamic work than for the dynamic work. This was also the case for heart rate and forearm skin temperature (p<0.01), and for auditory canal temperature (p<0.05). There was no significant difference between the two types of work for mean skin temperature, calf skin temperature and chest skin temperature. These results show that for the same external work, physiological strain and perceived exertion are greater for mixed static and dynamic work (carrying a load in the arms) than for mainly dynamic work (walking on a treadmill). They suggest that it is not appropriate to make direct comparisons of laboratory studies based on dynamic work, with practical situations containing mixed static and dynamic work in the heat.     

Nerve growth factor depletion by autoimmunization produces thermal hypoalgesia in adult rats

Nerve growth factor (NGF) plays a role in mechanisms of inflammation and hyperalgesia in adult animals. We sought to determine if NGF depletion produced by autoimmunization of adult rats altered their thermal sensitivity to an acute noxious thermal stimulus. Anti-NGF IgG was not detected in the cerebrospinal fluid of any tested samples. Only those rats with the highest anti-NGF serum titers showed significant (P<0.05) thermal hypoalgesia measured using the hot plate test (52°C): the mean (±S.D.) hind paw lick latency of rats in the high anti-NGF titer group was 18.0±4.6 s compared to means of 10.8±4.3 s, 9.2±2.6 s and 10.1±3.0 s in the medium, low and control groups, respectively. Thus, NGF depletion by autoimmunization is a useful model for investigating the role of NGF in behavioral responses of adult rats to noxious stimuli, providing high titers of antibody are present.     

Chlordimeform produces profound, selective, and transient changes in visual evoked potentials of hooded rats

Rat visual function was tested after acute exposure to chlordimeform (CDM), a formamidine insecticide/acaricide. Adult male Long-Evans rats were surgically implanted with epidural recording electrodes overlying visual cortex and tested 1 week later. Pattern reversal-evoked potentials (PREPs), flash-evoked potentials (FEPs), and FEP recovery ratios were measured after acute CDM administration. Averaged recordings obtained during 200 reversals of a black-and-white square wave grating comprised the PREPs, and those obtained during 128 paired strobe lamp flashes comprised the FEPs. In the first study, which examined dose-response relationships, i.p. injections of 0 (saline), 5, 15, or 40 mg/kg CDM-HCl were administered 30 min prior to testing. The PREP amplitudes showed large dose-related changes in the CDM-treated rats. PREP N1P1 and P1N3 peak-to-peak amplitudes increased more than 200% in the 40 mg/kg group. In contrast, FEP amplitudes and FEP recovery ratios were unchanged by CDM. Both PREP and FEP peak latencies were increased by CDM in dose-related fashions. In the second study, which examined the time course of CDM action, PREPs and paired-pulse FEPs were recorded 3, 6, and 24 h after dosage with either 0 or 40 mg/kg CDM. All evoked potential changes were large at 3 and 6 h, but had returned to control values by 24 h. In summary, acute exposure to CDM temporarily increased both the amplitude and latency of PREPs, but only the latency of FEPs.