2,274 research outputs found

    Asphyxiating Thoracic Dysplasia(SNUCH CPC-40)

    Get PDF
    (Clinicopathologic Conference) This newborn male infant was transferred to NICU of Sowha Children's Hospital from a private OB & Gyn Clinic. He was the first baby of this mother, and the gestational period was 41 weeks. No history of illness or drug administration during this pregnancy was elicited. There was no perinatal problems. His Apgar score was 7 at 1 rninute and 8 at 5 minutes. At the time of admission his body weight was 2,880 gm; body length 50cm; head circumference 35cm and chest circumference 27cm. Body temperature was 36.7˚C, pulse rate 148per minute and respiratory rate 70 per minute. He was cyanotic generally and the crying was weak

    Optimization of magnetic flux density for fast MREIT conductivity imaging using multi-echo interleaved partial fourier acquisitions

    Get PDF
    BACKGROUND: Magnetic resonance electrical impedance tomography (MREIT) has been introduced as a non-invasive method for visualizing the internal conductivity and/or current density of an electrically conductive object by externally injected currents. The injected current through a pair of surface electrodes induces a magnetic flux density distribution inside the imaging object, which results in additional magnetic flux density. To measure the magnetic flux density signal in MREIT, the phase difference approach in an interleaved encoding scheme cancels out the systematic artifacts accumulated in phase signals and also reduces the random noise effect by doubling the measured magnetic flux density signal. For practical applications of in vivo MREIT, it is essential to reduce the scan duration maintaining spatial-resolution and sufficient contrast. In this paper, we optimize the magnetic flux density by using a fast gradient multi-echo MR pulse sequence. To recover the one component of magnetic flux density B(z), we use a coupled partial Fourier acquisitions in the interleaved sense. METHODS: To prove the proposed algorithm, we performed numerical simulations using a two-dimensional finite-element model. For a real experiment, we designed a phantom filled with a calibrated saline solution and located a rubber balloon inside the phantom. The rubber balloon was inflated by injecting the same saline solution during the MREIT imaging. We used the multi-echo fast low angle shot (FLASH) MR pulse sequence for MRI scan, which allows the reduction of measuring time without a substantial loss in image quality. RESULTS: Under the assumption of a priori phase artifact map from a reference scan, we rigorously investigated the convergence ratio of the proposed method, which was closely related with the number of measured phase encode set and the frequency range of the background field inhomogeneity. In the phantom experiment with a partial Fourier acquisition, the total scan time was less than 6 seconds to measure the magnetic flux density B(z) data with 128×128 spacial matrix size, where it required 10.24 seconds to fill the complete k-space region. CONCLUSION: Numerical simulation and experimental results demonstrated that the proposed method reduces the scanning time and provides the recovered B(z) data comparable to what we obtained by measuring complete k-space data

    Mouse genetics: Catalogue and scissors

    Get PDF
    Phenotypic analysis of gene-specific knockout (KO) mice has revolutionized our understanding of in vivo gene functions. As the use of mouse embryonic stem (ES) cells is inevitable for conventional gene targeting, the generation of knockout mice remains a very time-consuming and expensive process. To accelerate the large-scale production and phenotype analyses of KO mice, international efforts have organized global consortia such as the International Knockout Mouse Consortium (IKMC) and International Mouse Phenotype Consortium (IMPC), and they are persistently expanding the KO mouse catalogue that is publicly available for the researches studying specific genes of interests in vivo. However, new technologies, adopting zinc-finger nucleases (ZFNs) or Transcription Activator-like Effector (TALE) Nucleases (TALENs) to edit the mouse genome, are now emerging as valuable and effective shortcuts alternative for the conventional gene targeting using ES cells. Here, we introduce the recent achievement of IKMC, and evaluate the significance of ZFN/TALEN technology in mouse genetics. [BMB Reports 2012; 45(12): 686-692]

    Reconfigurable Intelligent Surface-Aided Wireless Power Transfer Systems: Analysis and Implementation

    Full text link
    Reconfigurable intelligent surface (RIS) is a promising technology for RF wireless power transfer (WPT) as it is capable of beamforming and beam focusing without using active and power-hungry components. In this paper, we propose a multi-tile RIS beam scanning (MTBS) algorithm for powering up internet-of-things (IoT) devices. Considering the hardware limitations of the IoT devices, the proposed algorithm requires only power information to enable the beam focusing capability of the RIS. Specifically, we first divide the RIS into smaller RIS tiles. Then, all RIS tiles and the phased array transmitter are iteratively scanned and optimized to maximize the receive power. We elaborately analyze the proposed algorithm and build a simulator to verify it. Furthermore, we have built a real-life testbed of RIS-aided WPT systems to validate the algorithm. The experimental results show that the proposed MTBS algorithm can properly control the transmission phase of the transmitter and the reflection phase of the RIS to focus the power at the receiver. Consequently, after executing the algorithm, about 20 dB improvement of the receive power is achieved compared to the case that all unit cells of the RIS are in OFF state. By experiments, we confirm that the RIS with the MTBS algorithm can greatly enhance the power transfer efficiency

    Detection of the Upper Airway Obstruction using Electrical Impedance Tomography

    Get PDF
    Obstructive sleep apnea (OSA) is caused by the occlusion of the upper airway. No real-time imaging technique, which can detect such occlusion during natural sleep, exists at the moment. The surface electrodes were attached on the face and neck, and then changes in the conductivity image of the upper airway were successfully detected

    Lobeglitazone Attenuates Airway Inflammation and Mucus Hypersecretion in a Murine Model of Ovalbumin-Induced Asthma

    Get PDF
    Lobeglitazone (LB) is a novel agonist of peroxisome proliferator-activated receptor (PPAR)-α and γ that was developed as a drug to treat diabetes mellitus. We explored the ameliorative effects of LB on allergic asthma using a murine model of ovalbumin (OVA)-induced asthma. To boost the immune response of animals, OVA sensitization was performed on days 0 and 14. LB (250 or 500 μg/kg) was administered by oral gavage on days 18 to 23, and the OVA challenge was performed using an ultrasonic nebulizer on days 21 to 23. Plethysmography showed airway hyperresponsiveness (AHR) on day 24. LB treatment effectively decreased inflammatory cell recruitment, T-helper type 2 cytokines in the bronchoalveolar lavage fluid, and immunoglobulin (Ig) E in the serum of the animals with OVA-induced asthma, which was accompanied by a marked reduction in AHR. It also decreased airway inflammation, mucus hypersecretion, phosphorylation of nuclear transcription factor-kappa-B (NF-κB), and expression of activating protein (AP)-1 and mucin 5AC (MUC5AC). Overall, LB effectively attenuated the pathophysiological changes of asthma and its effects appear related to a reduction in the phosphorylation of NF-κB and the expression of AP-1. Thus, our results suggest that LB has a potential to treat allergic asthma

    Multiple Intracranial Tuberculomas Mimicking Granulocytic Sarcomas in Acute Myeloid Leukemia

    Get PDF
    The diagnosis of incracranial tuberculoma in immune-compromised hosts is often difficult because conventional magnetic resonance (MR) imaging of tuberculoma reveals various findings and neurologic symptoms are not typical. Here, we report a case of a 54-yr old man with multiple intracranial tuberculoma who was treated for acute myeloid leukemia. He complained of right-side paresthesia after the third consolidation chemotherapy without leukemic relapse and fever. MR imaging of the brain showed multiple ring-enhanced lesions in the cerebrum, cerebellar hemisphere, and pons. The lesions appeared to mimic a metastatic tumor or abscess. Cerebrospinal fluid analysis showed no abnormal cells, but the level of adenosine deaminase was elevated (28.8 IU/L, normal 0-8). Stereotactic brain biopsy was performed, but only reactive gliosis was observed. To confirm diagnosis, an open brain biopsy was performed. The histopathology demonstrated chronic granulomatous inflammation with caseous necrosis. Tuberculous-polymerase chain reaction of the biopsy showed a positive result. He was treated with anti-tuberculosis medication and a high dose of steroid. Paresthesia improved, and follow-up brain MR imaging showed the decreased size and numbers of ring-enhanced lesions and improvement of perilesional edema 1 month after treatment. Here, we report on an interesting case of intracranial tuberculoma in acute myeloid leukemia
    corecore