The respiratory sound features of COVID-19 patients fill gaps between clinical data and screening methods

BackgroundThe 2019 novel coronavirus (COVID-19) has continuous outbreaks around the world. Lung is the main organ that be involved. There is a lack of clinical data on the respiratory sounds of COVID-19 infected pneumonia, which includes invaluable information concerning physiology and pathology. The medical resources are insufficient, which are now mainly supplied for the severe patients. The development of a convenient and effective screening method for mild or asymptomatic suspicious patients is highly demanded. MethodsThis is a retrospective case series study. 10 patients with positive results of nucleic acid were enrolled in this study. Lung auscultation was performed by the same physician on admission using a hand-held portable electronic stethoscope delivered in real time via Bluetooth. The recorded audio was exported, and was analyzed by six physicians. Each physician individually described the abnormal breathing sounds that he heard. The results were analyzed in combination with clinical data. Signal analysis was used to quantitatively describe the most common abnormal respiratory sounds. ResultsAll patients were found abnormal breath sounds at least by 3 physicians, and one patient by all physicians. Cackles, asymmetrical vocal resonance and indistinguishable murmurs are the most common abnormal breath sounds. One asymptomatic patient was found vocal resonance, and the result was correspondence with radiographic computed tomography. Signal analysis verified the credibility of the above abnormal breath sounds. ConclusionsThis study describes respiratory sounds of patients with COVID-19, which fills up for the lack of clinical data and provides a simple screening method for suspected patients.

Accelerated magnetic resonance spectroscopy with Vandermonde factorization.

Multi-dimensional magnetic resonance spectroscopy is an important tool for studying molecular structures, interactions and dynamics in bio-engineering. The data acquisition time, however, is relatively long and non-uniform sampling can be applied to reduce this time. To obtain the full spectrum,a reconstruction method with Vandermonde factorization is proposed. This method explores the general signal property in magnetic resonance spectroscopy: Its time domain signal is approximated by a sum of a few exponentials. Results on synthetic and realistic data show that the new approach can achieve faithful spectrum reconstruction and outperforms state-of-the-art low rank Hankel matrix method.

Projected Iterative Soft-Thresholding Algorithm for Tight Frames in Compressed Sensing Magnetic Resonance Imaging.

Compressed sensing (CS) has exhibited great potential for accelerating magnetic resonance imaging (MRI). In CS-MRI, we want to reconstruct a high-quality image from very few samples in a short time. In this paper, we propose a fast algorithm, called projected iterative soft-thresholding algorithm (pISTA), and its acceleration pFISTA for CS-MRI image reconstruction. The proposed algorithms exploit sparsity of the magnetic resonance (MR) images under the redundant representation of tight frames. We prove that pISTA and pFISTA converge to a minimizer of a convex function with a balanced tight frame sparsity formulation. The pFISTA introduces only one adjustable parameter, the step size, and we provide an explicit rule to set this parameter. Numerical experiment results demonstrate that pFISTA leads to faster convergence speeds than the state-of-art counterpart does, while achieving comparable reconstruction errors. Moreover, reconstruction errors incurred by pFISTA appear insensitive to the step size.

Effects of Jianpi Jiedu Recipe on reversion of P-glycoprotein-mediated multidrug resistance through COX-2 pathway in colorectal cancer / 中国结合医学杂志

<p><b>OBJECTIVE</b>To evaluate the underlying mechanism of Jianpi Jiedu Recipe (, JJR) in the reversion of multidrug resistance concerning colorectal cancer in vitro and in vivo.</p><p><b>METHODS</b>Mice were treated orally with JJR at a daily 4.25 g/(kg·day) or injected with vinblastine (VCR) 2.5 mg/(kg·day) for 3 weeks after having been inoculated with HCT8/V cells; tumor tissues were assayed by hematoxylin and eosin staining. Firstly, the effects of JJR on the expression of cyclooxygenase-2 (COX-2) were tested by real-time polymerase chain reaction (PCR) technique and COX-2 gene silenced by siRNA. Secondly, the variation of intracellular concentration of oxaliplatin (L-OHP) was evaluated by the inductively coupled plasma mass spectroscopy (ICPMS) in HCT8/V and its COX-2 siRNA cells; the concentration of JJR combined with chemotherapeutic drugs and the reverse effect of multidrug resistance (MDR) in HCT8/V cells was evaluated by the MTT assay. Thirdly, real-time quantitative PCR and Western blot analysis were used to detect the multidrug resistance gene 1 (MDR1) mRNA and P-gp expression.</p><p><b>RESULTS</b>JJR had an inhibitory effect on the growth of tumors in vivo, and it, in combination with chemotherapeutic drugs, could reverse the drug-resistance of HCT8/V cells and increase the sensitivity of HCT8/V cells to VCR, DDP, 5-Fu, and THP. ICP-MS results showed that JJR could increase the concentration of drugs in HCT8/V cells (P<0.01). Furthermore, it was shown that JJR could reverse drug resistance of colorectal cancer cells by decreasing MDR1 expression and P-gp level via downregulation of COX-2, which has been represented as one of the major mechanisms that contributes to the MDR phenotype (P<0.01).</p><p><b>CONCLUSION</b>JJR reversed multidrug resistance and enhanced the sensitivity to chemotherapy, which could be attributed to the down-regulation of COX-2 in MDR1/P-gp-mediated MDR colorectal cancer after chemotherapy.</p>

Evaluation on left ventricular systolic synchronicity and cardiac function in patients with permanent cardiac pacing by real-time three-dimensional echocardiography / 中华心血管病杂志

<p><b>OBJECTIVE</b>To determine the feasibility on the left ventricular systolic synchronism and cardiac function evaluation in patients with permanent cardiac pacing by real-time three-dimensional echocardiography.</p><p><b>METHODS</b>Fifteen patients with sick sinus syndrome post dual-chamber pacemaker implantation were enrolled in this study. Pacemakers were programmed to AAI, DDD, and VVI respectively. After pacing for 5 minutes in each mode, participants were examined with real-time three-dimensional echocardiography. Images in different pacing modes were obtained and analyzed by the off-line Qlab 4.2 software. Parameters including global and 17-segmental volume-time curves (VTCs), dispersion of time to minimal regional volume for 16, 12, and 6 left ventricular segments (Tmsv16-s, Tmsv12-s, Tmsv6-s), and maximal difference of time to minimal regional volume for l6, 12 and 6 left ventricular segments (Tmsv16-dif, Tmsv12-dif, Tmsv6-dif), end diastolic volume (EDV), end systolic volume (ESV), left ventricular ejection fraction (LVEF) were measured respectively. Parameters of peak filling rate (PFR), regional end diastolic volume (rEDV), regional end systolic volume (rESV), and regional ejection fraction (rEF) were also calculated.</p><p><b>RESULTS</b>Left ventricular systolic synchronism as reflected by VTCs, Tmsv16-s, Tmsv12-s, Tmsv6-s, Tmsv16-dif, Tmsv12-dif and Tmsv6-dif as well as parameters reflecting ventricular function, i.e., LVEF, PFR were significantly better in AAI mode than in DDD and VVI models (all P < 0.05). All above indexes were similar between DDD and VVI models (all P > 0.05). rEFs of left inferior wall in base, septum in base and apex were significantly lower in DDD and VVI models compared that in AAI mode (P < 0.05).</p><p><b>CONCLUSION</b>Real-time three-dimensional echocardiography can objectively and accurately evaluate left ventricular systolic synchronism and cardiac function in patients with permanent cardiac pacing and AAI mode is superior to DDD and VVI models.</p>