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The effect of inulin addition at low concentrations (0.1–0.5%) on the thermal gelation of oat protein gels was investigated using textural profile analysis, rheological measurements and microstructure observation through scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Results indicate that oat protein hexamers were dissociated with heat into monomers, which then became the reactive units involved in the development of a unique percolating network. The major forces responsible for the establishment of the structure were disulphide bonds, as well as hydrogen bonds and hydrophobic forces. A small amount of inulin can greatly increase the compressive stress of the gels prepared at pH 7 from 13.93 to 22.98 kPa. This is related to the phase separation phenomena produced during heating, which increased the apparent protein concentration. Moreover, inulin formed nanoparticles in the void spaces of the protein network performing a filling effect and creating junction zones. Localized interactions such as hydrogen and hydrophobic bonds were possible between protein and inulin at the borders of junction zones. This research has provided a new approach to make strong oat protein gels at neutral pH. Future applications may promote the utilization of oat protein as a plant derived gelling ingredient in a wide range of food applications. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to use resting-state functional connectivity (rsFC) and amplitude of low-frequency fluctuation (ALFF) methods to explore intrinsic default-mode network (DMN) impairment after sleep deprivation (SD) and its relationships with clinical features. Methods: Twelve healthy male subjects underwent resting-state functional magnetic resonance imaging twice: once following rested wakefulness (RW) and the other following 72 hours of total SD. Before the scans, all subjects underwent the attention network test (ANT). The independent component analysis (ICA), rsFC, and ALFF methods were used to examine intrinsic DMN impairment. Receiver operating characteristic (ROC) curve was used to distinguish SD status from RW status. Results: Compared with RW subjects, SD subjects showed a lower accuracy rate (RW =96.83%, SD =77.67%; P<0.001), a slower reaction time (RW =695.92 ms; SD =799.18 ms; P=0.003), a higher lapse rate (RW =0.69%, SD =19.29%; P<0.001), and a higher intraindividual coefficient of variability in reaction time (RW =0.26, SD =0.33; P=0.021). The ICA method showed that, compared with RW subjects, SD subjects had decreased rsFC in the right inferior parietal lobule (IPL, BA40) and in the left precuneus (PrC)/posterior cingulate cortex (PCC) (BA30, 31). The two different areas were selected as regions of interest (ROIs) for future rsFC analysis. Compared with the same in RW subjects, in SD subjects, the right IPL showed decreased rsFC with the left PrC (BA7) and increased rsFC with the left fusiform gyrus (BA37) and the left cluster of middle temporal gyrus and inferior temporal gyrus (BA37). However, the left PrC/ PCC did not show any connectivity differences. Compared with RW subjects, SD subjects showed lower ALFF area in the left IPL (BA39, 40). The left IPL, as an ROI, showed decreased rsFC with the right cluster of IPL and superior temporal gyrus (BA39, 40). ROC curve analysis showed that the area under the curve (AUC) value of the left IPL was 0.75, with a cutoff point of 0.834 (mean ALFF signal value). Further diagnostic analysis exhibited that the AUC alone discriminated SD status from RW status, with 75% sensitivity and 91.7% specificity. Conclusion: Long-term SD disturbed the spontaneous activity and connectivity pattern of DMN. [ABSTRACT FROM AUTHOR]

Crop trees were selected in a 26-year-old even-aged Cunninghamia lanceolata plantation in Lin' an, and compared in plots that were released and unreleased to examine growth and structure responses for 3 years after thinning. Crop tree release significantly increased the mean increments of diameter and volume of individual tree by 1.30 and 1.25 times relative to trees in control stands, respectively. The increments of diameter and volume of crop trees were significantly higher than those of general trees in thinning plots, crop trees and general trees in control plots, which suggested that the responses from different tree types to crop tree release treatment were different. Crop tree release increased the average distances of crop trees to the nearest neighboring trees, reducing competition among crop trees by about 68.2%. 3-year stand volume increment for thinning stands had no significant difference with that of control stands although the number of trees was only 81.5% of the control. Crop trees in thinned plots with diameters over than 14 cm reached 18.0% over 3 years, compared with 12.0% for trees without thinning, suggesting that crop tree release benefited the larger individual trees. The pattern of tree locations in thinning plots tended to be random, complying with the rule that tree distribution pattern changes with growth. Crop tree release in C. lanceolata plantation not only promoted the stand growth, but also optimized the stand structure, benefiting crop trees sustained rapid growth and larger diameter trees production. [ABSTRACT FROM AUTHOR]

Purpose Long scanning time greatly hinders the widespread application of spin-lattice relaxation in rotating frame ( [ABSTRACT FROM AUTHOR]

Oligodontia, which is the congenital absence of six or more permanent teeth, excluding the third molars, may contribute to masticatory dysfunction, speech alteration, aesthetic problems and malocclusion. Msh homeobox 1 (MSX1) was the first gene identified as causing non-syndromic oligodontia. In this study, we identified a novel heterozygous non-stop mutation (c.910_911dupTA, p.*304Tyrext*48) in MSX1 in a Chinese family with autosomal dominant non-syndromic oligodontia. This novel mutation substitutes the stop codon with a tyrosine residue, potentially adding 48 amino acids to the C-terminus of MSX1. Further in vitro study found that mutant MSX1 could be expressed but had lost its ability to enter the nucleus. This is the first report indicating that a non-stop mutation in MSX1 is responsible for oligodontia. This study broadens the mutation spectrum for MSX1 and provides a new way to clarify the mechanism of MSX1 in tooth agenesis. [ABSTRACT FROM AUTHOR]

Four kinds of thinning treatments were designed including thinning from below, thinning from above, mechanical thinning and crop tree release with the same thinning intensity on the 14- year-old pure Cunninghamia laceolata and Pinus massoniana plantations in Guangxi, and 6 kinds of size inequality indices were applied including stand deviation, variation coefficient, skewness, Gini coefficient, Kuznetz coefficient and Lorenz asymmetry coefficient to evaluate the change of individual volume inequality after the 4 kinds of thinning regimes applied. The results showed that stand deviation, variation coefficient, Gini coefficient and Kuznetz coefficient decreased and skewness increased after thinning from below or above compared with before thinning, while after crop tree release these four indices increased and skewness was uncertain. Lorenz asymmetry coefficient increased after thinning from below while it decreased after thinning from above or crop tree release compared with before thinning. There was no distinct rule for the 6 kinds of size inequality indices after mechanical thinning. The size inequality increased after crop tree release while it decreased after thinning from above or below. The study suggested that Lorenz curve, Gini coefficient and Lorenz asymmetry coefficient could be used to compare the size inequality statically and dynamically among different stands, and could be discriminated the difference of size inequality caused by the different thinning regimes. Lorenz asymmetry coefficient even could be applied to tell the size inequality was mainly from the larger or smaller individuals. Crop tree release method in close-to-nature management could lessen the competition pressures of crop trees and increase the size inequality of the stand effectively which would be helpful to maintain the dominant position of crop trees. [ABSTRACT FROM AUTHOR]

Purpose To automatically and robustly detect the arterial input function (AIF) with high detection accuracy and low computational cost in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Materials and Methods In this study, we developed an automatic AIF detection method using an accelerated version (Fast-AP) of affinity propagation (AP) clustering. The validity of this Fast-AP-based method was proved on two DCE-MRI datasets, i.e., rat kidney and human head and neck. The detailed AIF detection performance of this proposed method was assessed in comparison with other clustering-based methods, namely original AP and K-means, as well as the manual AIF detection method. Results Both the automatic AP- and Fast-AP-based methods achieved satisfactory AIF detection accuracy, but the computational cost of Fast-AP could be reduced by 64.37-92.10% on rat dataset and 73.18-90.18% on human dataset compared with the cost of AP. The K-means yielded the lowest computational cost, but resulted in the lowest AIF detection accuracy. The experimental results demonstrated that both the AP- and Fast-AP-based methods were insensitive to the initialization of cluster centers, and had superior robustness compared with K-means method. Conclusion The Fast-AP-based method enables automatic AIF detection with high accuracy and efficiency. J. Magn. Reson. Imaging 2014;39:1327-1337. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate if diffusion tensor imaging (DTI) can distinguish the disease process of radiation-induced brain injury when combined with apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values. Twenty-one rabbits received irradiation of 100 Gy in the right brain hemisphere. Twelve rabbits were screened with magnetic resonance imaging (MRI) and DTI before radiation, and imaged at every week until week 9 following radiation. The rabbits that had MRI were euthanized at week 9 for histologic evaluation, while other nine rabbits without MRI were randomly killed for histologic evaluation at weeks 2, 4 and 6, respectively. From the DTI, the ADC and FA values were measured, and rADC and rFA were calculated. After radiation, the trend of the ADC value can be divided into three stages. In the first stage, the ADC value of the target tissues gradually decreased. In the second stage, the ADC value of white matter in the target tissues showed a recovery trend, back to the initial level similar to that in contralateral. In the third stage, the ADC value of white matter in the target tissue continues to increase over the ADC value of baseline and contralateral white matter. The FA value of radiation-targeted area showed continuous decreasing tendency. Pathological evaluation showed the different features in three stages. DTI can distinguish the different disease stages when combined with the ADC and FA values. [ABSTRACT FROM AUTHOR]

Fabrication of functional devices on arbitrary non-conventional substrates has significant advantages for broadening devices applications and the development of soft electronic systems such as flexible, stretchable, wearable, and epidermal electronic modules. Information storage device is one of crucial electronic elements in modern digital circuitries. Herein, a re-writable, transferable, and flexible sticker-type organic memory on universal substrates is demonstrated through a facile and cost-effective one-step strategy. The organic memory sticker based on the graphene electrode grown by chemical vapor deposition consists of a blending composite of polymer (poly (methyl methacrylate) (PMMA):poly (3-hexylthiophene) (P3HT) in chlorobenzene (CB) fabricated by mature solution processes and facilities. By combining with the mechanical elastic of organic material and graphene electrode, the sticker-type organic memory can be easily tagged on non-planar or flexible substrates after etching away the supporting metal. Particularly, the new attachable sticker-type memory processes a unique feature of re-programmable capability. It is believed that the universal substrate selectivity of the sticker-type organic memory with re-writable characteristic revealed here may greatly enlarge information storage devices in immense areas and advance the future functional soft circuitries. [ABSTRACT FROM AUTHOR]

Objective: A screening survey for osteoporotic fractures in men and women in Hong Kong represents the first large-scale prospective population-based study on bone health in elderly (≥65 years) Chinese men and women. This study aims to identify the prevalence and potential risk factors of lumbar spondylolisthesis in these subjects. Methods: The lateral lumbar radiographs of 1,994 male and 1,996 female patients were analysed using the Meyerding classification. Results: Amongst the men, 380 (19.1 %) had at least one spondylolisthesis and 43 (11.3 %) had slips at two or more levels; 283 had anterolisthesis, 85 had retrolisthesis, whereas 12 subjects had both anterolisthesis and retrolisthesis. Amongst the women, 499 (25.0 %) had at least one spondylolisthesis and 69 (13.8 %) had slips at two or more levels; 459 had anterolisthesis, 34 had retrolisthesis, whereas 6 subjects had both anterolisthesis and retrolisthesis. Advanced age, short height, higher body mass index (BMI), higher bone mineral density (BMD) and degenerative arthritis are associated with spondylolisthesis. Lower Physical Activity Scale for the Elderly (PASE) score was associated with spondylolisthesis in men; higher body weight, angina and lower grip strength were associated with spondylolisthesis in women. Conclusion: The male/female ratio of lumbar spondylolisthesis prevalence was 1:1.3 in elderly Chinese. Men are more likely to have retrolisthesis. Key Points: • The prevalence of spondylolisthesis is 19.1 % in elderly Chinese men. • The prevalence of spondylolisthesis is 25.0 % in elderly Chinese women. • Men are more likely to have retrolisthesis. • Anterolisthesis is most commonly seen at the L4/L5 level. • Retrolisthesis is most commonly seen at the L3/L4 level. [ABSTRACT FROM AUTHOR]

Tuberculosis is a major health threat in many regions of the world. Opportunistic infections in immunocompromised HIV/AIDS patients and multi-drug-resistant bacterial strains have exacerbated the problem, while diagnosing tuberculosis still remains a challenge. When left undiagnosed and thus untreated, mortality rates of patients with tuberculosis are high. Standard diagnostics still rely on methods developed in the last century. They are slow and often unreliable. In an effort to reduce the burden of the disease, this paper presents our automated approach for detecting tuberculosis in conventional posteroanterior chest radiographs. We first extract the lung region using a graph cut segmentation method. For this lung region, we compute a set of texture and shape features, which enable the X-rays to be classified as normal or abnormal using a binary classifier. We measure the performance of our system on two datasets: a set collected by the tuberculosis control program of our local county's health department in the United States, and a set collected by Shenzhen Hospital, China. The proposed computer-aided diagnostic system for TB screening, which is ready for field deployment, achieves a performance that approaches the performance of human experts. We achieve an area under the ROC curve (AUC) of 87% (78.3% accuracy) for the first set, and an AUC of 90% (84% accuracy) for the second set. For the first set, we compare our system performance with the performance of radiologists. When trying not to miss any positive cases, radiologists achieve an accuracy of about 82% on this set, and their false positive rate is about half of our system's rate. [ABSTRACT FROM AUTHOR]

This study investigated the effects of nitrate on bone mineral density (BMD) and bone marrow perfusion in ovariectomized (OVX) female rats, and also the effects of nitrate on in vitro osteoblastic activity and osteoclastic differentiation of murine monocyte/ macrophage RAW 264.7 cells. Female Sprague—Dawley rats were divided into OVX + nitrate group (isosorbide-5-mononitrate, ISM, 150 mg/kg/day b.i.d), OVX + vehicle group, and control group. Lumbar spine CT bone densitometry and perfusion MRI were performed on the rats at baseline and week 8 post-OVX. The OVX rats' BMD decreased by 22.5% ± 5.7% at week 8 (p < 0.001); while the OVX + ISM rats' BMD decreased by 13.1% ± 2.7% (p < 0.001). The BMD loss difference between the two groups of rats was significant (p = 0.018). The OVX rats' lumbar vertebral perfusion MRI maximum enhancement (Emax) decreased by 10.3% ± 5.0% at week 8 (p < 0.005), while in OVX + ISM rats, the Emax increased by 5.5% ± 6.9% (p > 0.05). The proliferation of osteoblast-like UMR-106 cells increased significantly with ISM treatment at 0.78 μM to 50 μM. Treatment of UMR-106 cells with ISM also stimulated the BrdU uptake. After the RAW 264.7 cells were co-treated with osteoclastogenesis inducer RANKL and 6.25 μM ~ 100 μM of ISM for 3 days, a trend of dose-dependent increase of osteoclast number was noted. [ABSTRACT FROM AUTHOR]

Objective: To determine the relative performance of T1rho and T2 relaxation times in disc degeneration assessment.Methods: Lumbar sagittal MRI was performed at 3 T in 52 subjects. With a spin-lock frequency of 500 Hz, T1rho was measured using a rotary echo spin-lock pulse embedded in a three-dimensional (3D) balanced fast field echo sequence. A multi-echo TSE sequence was used for T2 mapping. Regions of interest (ROIs) were drawn over the T1rho and T2 maps, including nucleus pulposus (NP) and annulus fibrosus (AF). Eight- and five-level disc degeneration semi-quantitative grading was performed.Results: For NP, T1rho and T2 decreased quadratically with disc degeneration grades and had no significant trend difference (P = 0.40). For AF, T1rho decreased linearly as the disc degenerated and had a slope of -3.02 and -4.56 for eight- and five-level gradings respectively; while the slopes for T2 values were -1.43 and -1.84 respectively, being significantly flatter than those of T1rho (P < 0.001). There was no significant difference in T1rho and T2 values for both NP and AF among discs of grade 5/8 to 8/8 degeneration.Conclusion: T1rho is better suited for evaluating AF in degenerated disc than T2. In NP, T1rho and T2 decrease in a similar pattern following disc degeneration. [ABSTRACT FROM AUTHOR]

The chemical exchange (CE) process has been exploited as a novel and powerful contrast mechanism for MRI, which is primarily performed in the form of chemical exchange saturation transfer (CEST) imaging. A spin-lock (SL) technique can also be used for CE studies, although traditionally performed and interpreted quite differently from CEST. Chemical exchange imaging with spin-lock technique (CESL), theoretically based on the Bloch-McConnell equations common to CEST, has the potential to be used as an alternative to CEST and to better characterize CE processes from slow and intermediate to fast proton exchange rates through the tuning of spin-lock pulse parameters. In this study, the Z-spectrum and asymmetric magnetization transfer ratio (MTRasym) obtained by CESL are theoretically analyzed and numerically simulated using a general two-pool R1? relaxation model beyond the fastexchange limit. The influences of spin-lock parameters, static magnetic field strength B0 and physiological properties on the Z-spectrum and MTRasym are quantitatively revealed. Optimization of spin-lock frequency and spin-lock duration for the maximum CESL contrast enhancement is also investigated. Numerical simulation results in this study are compatible with the findings in the existing literature on CE imaging studies. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate sex hormone deficiency related osteoporosis and efficacy of different therapies. Methods: Orchiectomized and ovariectomized rat models are used to investigate sex hormone deficiency related osteoporosis and efficacy of different therapies. A rat vertebral body can be longitudinally divided into central portion, which contain more trabecular bone, and para-endplate portions which contain more compact bone. In matured male and female Wistar and Sprague-Dawley rat lumbar spines, we investigated baseline bone mineral density (BMD) characteristics and the differential segmental responses in bone loss within the lumbar vertebral body post gonadal surgery with clinical multidetector computed tomography. Results: Para-endplate sections had a higher BMD than central sections. The cephalad para-endplate sections had a higher BMD than the caudad para-endplate sections. Eight weeks after gonadal removal, there was more bone loss in central sections than para-endplate sections. The relative difference of bone loss between para-endplate and central sections was more apparent in male rats than in female rats. There was more bone loss in caudad sections than cephalad sections; this lead to a further increase of BMD difference between caudad para-endplate sections and cephalad para-endplate sections post gonadal surgery. Conclusion: The approach described in this study provided a consistent way to study BMD change within predominantly compact bone portion and trabecular bone portion of the vertebral body. [Copyright &y& Elsevier]

T1&rgr; relaxation is traditionally described as a mono-exponential signal decay with spin-lock time. However, T1&rgr; quantification by fitting to the monoexponential model can be substantially compromised in the presence of field inhomogeneities, especially for low spin-lock frequencies. The normal approach to address this issue involves the development of dedicated composite spin-lock pulses for artifact reduction while still using the mono-exponential model for T1&rgr; fitting. In this work, we propose an alternative approach for improved T1&rgr; quantification with the widely-used rotary echo spin-lock pulses in the presence of B0 inhomogeneities by fitting to a modified theoretical model which is derived to reveal the dependence of T1&rgr;-prepared magnetization on T1&rgr;, T2&rgr;, spin-lock time, spin-lock frequency and off-resonance, without involving complicated spin-lock pulse design. It has potentials for T1&rgr; quantification improvement at low spin-lock frequencies. Improved T1&rgr; mapping was demonstrated on phantom and in vivo rat spin-lock imaging at 3 T compared to the mapping using the mono-exponential model. [ABSTRACT FROM AUTHOR]

T1ρrelaxation has recently been found to be sensitive to liver fibrosis and has potential to be used for early detection of liver fibrosis and grading. Liver T1ρimaging and accurate mapping are challenging because of the long scan time, respiration motion and high specific absorption rate. Reduction and optimization of spin lock times (TSLs) are an efficient way to reduce scan time and radiofrequency energy deposition of T1ρ imaging, but maintain the near-optimal precision of T1ρ mapping. This work analyzes the precision in T1ρ estimation with limited, in particular two, spin lock times, and explores the feasibility of using two specific operator-selected TSLs for efficient and accurate liver T1ρ mapping. Two optimized TSLs were derived by theoretical analysis and numerical simulations first, and tested experimentally by in vivo rat liver T1ρ imaging at 3 T. The simulation showed that the TSLs of 1 and 50 ms gave optimal T1ρ estimation in a range of 10-100 ms. In the experiment, no significant statistical difference was found between the T1ρ maps generated using the optimized two-TSL combination and the maps generated using the six TSLs of [1, 10, 20, 30, 40, 50] ms according to one-way ANOVA analysis (p = 0.1364 for liver and p = 0.8708 for muscle). [ABSTRACT FROM AUTHOR]

Purpose: This study was designed to assess the enhanced effect of high intensity focused ultrasound (HIFU) ablation with microbubbles on rabbit hepatic VX2 tumors and to compare the detection sensitivity of CEUS and CECT to determine the residual viable tissue after ablation of HIFU. Methods: Forty rabbits with hepatic VX2 tumors were randomly separated into two groups (20 animals per group) before HIFU ablation. A bolus of 0.2 mL of saline or a microbubble-based ultrasound (US) contrast agent was injected intravenously to group I rabbits and group II rabbits, respectively. The HIFU ablation procedure was started 15 s after the injection. Tumors were examined with grayscale contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT) immediately before and after HIFU ablation. Histopathologic assessment was performed immediately after treatment imaging. Results: Before ablation, intense contrast enhancement during arterial phase was observed at the whole tumors or the periphery of the tumors by CEUS and CECT. Lower HIFU energy was used in group II than in group I (P < 0.001). Histopathologic assessment revealed local residual viable tumor tissues due to incomplete ablation in 47.4% (9/19) of tumors in group I and 10% (2/20) of tumors in group II (P < 0.05). The concordance rate of CEUS (90.9%) with histopathology on residual tumor detection was higher than that of CECT (27.3%, P < 0.05). Conclusions: Introduction of the microbubble agent enhances HIFU therapeutic efficacy. CEUS proves to have high sensitivity in assessment of residual viable rabbit VX2 tumor after HIFU. [ABSTRACT FROM AUTHOR]

Background and purpose. The options for managing spontaneous intracerebral haemorrhage (ICH) include conservative treatment, surgical removal of the haematoma and minimally invasive treatment with clot aspiration and subsequent fibrinolytic therapy. The discussion over which treatment is best for ICH remains controversial and management of patients with spontaneous ICH continues to be a challenge. The purpose of this study is to investigate the feasibility and safety of frameless stereotactic aspiration and subsequent fibrinolytic therapy for the treatment of spontaneous ICH. Methods. Patients with spontaneous supratentorial ICH were treated by a frameless stereotactic aspiration using the YL-1 type of intracranial haematoma puncture needle, followed by subsequent fibrinolytic therapy with urokinase. Results. Forty-eight patients were enrolled in the study. The median age was 65 years (range, 40--79). The median initial Glasgow Coma Scale (GCS) was 10 (range 6--14). The mean initial haematoma volume was 56.5 cm3. Initial ICH volume was reduced by an average of 75%% (range 50--90%%). Ten patients (20.8%%) died before hospital discharge. By the 3-month follow-up, another two patients had died, resulting in an overall mortality of 25.0%%. For the primary end point, a good outcome (3-month GOS score >3) rate was noted in 41.7%% of the patients. No intraoperative death was observed in this study. There were a total of 14 (29.2%%) procedure-related complications, with an overall re-bleeding rate of 10.4%%. Conclusions. Frameless stereotactic aspiration using the YL-1 type of intracranial haematoma puncture needle and subsequent fibrinolytic therapy for the treatment of spontaneous ICH is a simple and safe procedure with low re-bleeding rate and mortality. [ABSTRACT FROM AUTHOR]