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"Chen, Xu-Yan"
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Klebsiella pneumoniae invasion syndrome: a case of liver abscess combined with lung abscess, endophthalmitis, and brain abscess
Klebsiella pneumoniae invasion syndrome (KPIS) is a critical multi-site infection that is usually caused by highly virulent Klebsiella pneumonia. It is relatively common in Asian patients with diabetes and leads to sepsis, which has a high mortality rate. We report the case of a man in his early 40s who presented to the hospital with blurred vision in his left eye of 7 days’ duration and fever of 1 day’s duration. After a complete examination, he was diagnosed with KPIS on the basis of his liver abscessation, lung abscessation, endophthalmitis of the left eye and brain abscessation. After needle puncture and drainage of the left eye and liver abscess and anti-bacterial treatment with meropenem, the patient recovered well. When KPIS is suspected, attention should be paid to the sites of infection and the selection of the most appropriate antibiotics, but the most important aim should be to drain the lesions in a timely manner to improve the patient’s prognosis.
Journal Article
Chemometrics integrated with in silico pharmacology to reveal antioxidative and anti-inflammatory markers of dandelion for its quality control
Background
Dandelion is an herb with high nutritional and medicinal values, which has been listed in Chinese Pharmacopeia, European Pharmacopoeia and British Pharmacopoeia, gaining increasing acceptance around the world. However, the current quality control of dandelion is lagging behind. Only in Chinese Pharmacopeia, cichoric acid is used as a marker compound for its quality evaluation, whereas, it can not comprehensively reflect the bioactivity of dandelion.
Methods
This study developed a strategy by integrating chemometrics with in silico pharmacology to reveal the bioactive markers of dandelion for its quality control. Firstly, the major chemicals in dandelion were characterized using HPLC-DAD-MS/MS, and the corresponding antioxidant and anti-inflammatory activities were evaluated in vitro. Subsequently, the active components were screened by relating the chemicals and bioactivity of dandelion via grey relational assay and partial least squares regression analysis. The potential active components were then subjected to a validation for their activities. Moreover, in silico pharmacology was utilized to evaluate the contribution of active components to efficacy.
Results
A total of 22 phenolic compounds were characterized. Among them, cichoric acid, caffeic acid and luteolin were identified as quality markers owing to their good correlations with the bioactivities of dandelion. These three markers were quantified in frequently-used dandelion species, viz.
Taraxacum mongolicum
Hand.-Mazz. (TAM) and
T. officinale
F. H. Wigg. (TAO). TAM, with acceptably higher content of cichoric acid and caffeic acid, showed better antioxidant activity than TAO. While TAO included higher content of luteolin, presenting slightly more effective in anti-inflammation.
Conclusion
An useful strategy for the quality marker discovery was successfully designed. And the results provided more knowledge for the quality evaluation of dandelion.
Journal Article
Flexible Electrochemical Platform Coupled with In Situ Prepared Synthetic Receptors for Sensitive Detection of Bisphenol A
A flexible electrochemical sensor based on the carbon felt (CF) functionalized with Bisphenol A (BPA) synthetic receptors was developed. The artificial Bisphenol A receptors were grafted on the CF by a simple thermal polymerization molecular imprinting process. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and electrochemical characterizations were used to analyze the receptors. Characterization results demonstrated that the Bisphenol A synthetic receptors successfully formed on the CFs surface. Because the synthetic receptor and the porous CFs were successfully combined, the sensor displayed a better current response once Bisphenol A was identified. The sensor’s linear range was determined to be from 0.5 to 8.0 nM and 10.0 to 300.0 nM, with a detection limit of 0.36 nM. Even after being bent and stretched repeatedly, the electrode’s performance was unaffected, demonstrating the robustness, adaptability and viability of installing the sensor on flat or curved surfaces for on-site detection. The designed electrochemical sensor has been used successfully to identify Bisphenol A in milk samples with satisfactory results. This work provided a promising platform for the design of implantable, portable and miniaturized sensors.
Journal Article
MDA5-positive dermatomyositis without muscle weakness and rash: a case report and literature review
Melanoma differentiation-associated gene 5 (MDA5)-positive dermatomyositis (DM) is a rare systemic autoimmune disease associated with a high rate of mortality attributable to rapidly progressive interstitial lung disease. MDA5-positive DM is often complicated by a typical rash and muscle weakness. Herein, we describe a 50-year-old woman who presented with worsening pulmonary symptoms with an absence of typical clinical characteristics. We also review the treatments and prognosis made in similar cases, highlighting that closer attention should be paid to patients presenting with atypical DM, particularly when clinical manifestations such as rash and muscle weakness are not apparent.
Journal Article
A multicentre, randomized, controlled trial of oseltamivir in the treatment of influenza in a high-risk Chinese population
ABSTRACT
Objective: To evaluate the efficacy and safety of oseltamivir treatment in a population at high risk for influenza.
Research design and methods: This was a randomized, open-label, controlled trial involving Chinese patients with chronic respiratory diseases (chronic bronchitis, obstructive emphysema, bronchial asthma or bronchiectasis) or chronic cardiac disease. Patients showing symptoms of influenza were randomly assigned to receive oral oseltamivir 75 mg twice daily for 5 days (oseltamivir group), or symptomatic treatment (control group) within 48 h after symptom onset.
Main outcome measures: The main outcome measures were duration and severity of illness in influenza-infected patients. Other outcome measures included incidence of complications, antibiotic use, hospitalization and total medical cost.
Results: Of the 118 recruited patients, 56 were identified as influenza-infected through laboratory tests (oseltamivir, N = 27; control, N = 29). Relative to symptomatic treatment, oseltamivir significantly reduced the duration of influenza symptoms by 36.8% ( p = 0.0479), and the severity by 43.1% ( p = 0.0002). In addition, oseltamivir significantly reduced the duration of fever by 45.2% ( p = 0.0051), and the time to return to baseline health status by 5 days ( p = 0.0011). The incidence of complications (11% vs. 45%, p = 0.0053) and antibiotic use (37% vs. 69%, p = 0.0167) were also significantly lower in the oseltamivir group compared with the control group. The cost of treating influenza and its complications was comparable between the two groups ( p = 0.2462).
Conclusions: Oseltamivir is effective and well tolerated in high-risk patients with chronic respiratory or cardiac diseases. It can reduce the duration and severity of influenza symptoms and decrease the incidence of secondary complications and antibiotic use, without increasing the total medical cost.
Journal Article
Low-frequency E-field Detection Array(LFEDA)—Construction and preliminary results
In recent years, locating total lightning at the VLF/LF band has become one of the most important directions in lightning detection. The Low-frequency E-field Detection Array(LFEDA) consisting of nine fast antennas was developed by the Chinese Academy of Meteorological Sciences in Guangzhou between 2014 and 2015. This paper documents the composition of the LFEDA and a lightning-locating algorithm that applies to the low-frequency electric field radiated by lightning pulse discharge events(LPDEs). Theoretical simulation and objective assessment of the accuracy and detection efficiency of LFEDA have been done using Monte Carlo simulation and artificial triggered lightning experiment, respectively. The former results show that having a station in the network with a comparatively long baseline improves both the horizontal location accuracy in the direction perpendicular to the baseline and the vertical location accuracy along the baseline. The latter results show that detection efficiencies for triggered lightning flashes and return strokes are 100% and 95%, respectively. The average planar location error for return strokes of triggered lightning flashes is 102 m. By locating LPDEs in thunderstorms, we find that LPDEs are consistent with convective regions as indicated by strong reflectivity columns, and present a reasonable distribution in the vertical direction.In addition, the LFEDA can reveal an image of lightning development through mapping the channels of lightning. Based on three-dimensional locations, the vertical propagation speed of the preliminary breakdown and the changing trend of the leader’s speed in an intra-cloud and a cloud-to-ground flash are investigated. The research results show that the LFEDA has the capability for three-dimensional location of lightning, which provides a new technique for researching lightning development characteristics and thunderstorm electricity.
Journal Article
Non-Contact Measurement of Nugget Size of Spot Welding Using Focused Air-Coupled Ultrasound
Spot welding is widely used in the various fields of engineering and industries. Since the size, shape and mechanical properties of a nugget which is a zone melted and re-solidified during welding are closely related to the strength of the welded structure, quantitative evaluations of them are strongly required. In this work, an air-coupled ultrasound technique with focused transducers has been used for non-contact measurements of spot welds of steel plates. One-dimensional scanning in transmission configuration using a pair of focused air-coupled ultrasonic transducers operating with tone burst waves at 0.3 MHz is performed to obtain the amplitude profile of the transmitted ultrasound through the nugget area of a spot weld. A simple method for determining the nugget size from the profile of the transmitted ultrasound is proposed. To verify the validity of the method, calibration samples which imitate spot welds having different sizes of nuggets are prepared and used for demonstrating nugget size determinations. In addition, the proposed method has been applied to evaluate several spot welds fabricated with different electric currents (5 kA – 9 kA).
Journal Article
Prognostic factors affecting postoperative survival of patients with solitary small hepatocellular carcinoma
Background
Small hepatocellular carcinoma (sHCC) is a unique variant of HCC that is characterized by small tumor size (maximum tumor diameter ≤3 cm) and favorable long‐term outcomes. The present study aimed to define clinicopathologic factors that predict survival in patients with sHCC.
Methods
The study population consisted of 335 patients who underwent hepatectomy for solitary sHCC between December 1998 and 2010. Prognostic factors were evaluated using Kaplan–Meier curves and Cox proportional hazard models.
Results
The 5‐year overall survival (OS) and recurrence‐free survival (RFS) rates were 77.7% and 59.9%, respectively. Kaplan–Meier curves showed that tumor size and vascular invasion had prognostic significance within this relatively selected cohort (P < 0.05). Multivariate analysis confirmed that increased tumor size and vascular invasion were independent prognostic factors for short OS (hazard ratio [HR] = 2.367, 95% confidence interval [CI] 1.406–3.985; HR = 2.954, 95% CI 1.781–4.900) and RFS (HR = 1.779, 95% CI 1.259–2.514; HR = 1.699, 95% CI 1.165–2.477) in sHCC patients (P < 0.05). Importantly, a proposed prognostic scoring model was derived according to the two variables; tumor size and extent of vascular invasion were significantly associated with OS and RFS in patients with sHCC (P < 0.001).
Conclusions
Tumor size and vascular invasion are feasible and useful prognostic factors for sHCC. The proposed prognostic model, based on tumor size and vascular invasion, is informative in predicting survival in sHCC patients undergoing hepatectomy.
Journal Article
Simulation of the Dendrite Morphology and Microsegregation in Solidification of Al-Cu-Mg Aluminum Alloys
Since most typical alloys in industrial applications are multicomponent with three or more components, and various CA models proposed in the past mainly focus on the binary alloys, a two-dimensional modified cellular automaton model allowing for the quantitatively predicting dendrite growth of multicomponent alloys in the low P6clet number regime is presented. The elimination of the mesh-induced anisotropy is achieved by adopting a modified virtual front tracking method. A new efficient method based on the lever rule is applied to calculate the solid fraction increment of the interfacial cells. The thermodynamic data such as liquidus temperature, the partition coefficients, and the slope of liquidus surface, needed for determining the dynamics of dendrite growth, are obtained by coupling with PanEngine. This model is applied to simulate the dendrite morphology and microsegregation of A1-Cu-Mg temary alloy both for single and multi- dendrites growth. The simulated results demonstrate that the difference of the concentration distribution profiles ahead of the dendrite tip for each alloying element mainly results from the different partition coefficients and solute diffusion coefficients. Comparison with the prediction of analytical model is carded out and it reveals the correctness of the model. Consequently, the difference in interdendritic microsegregation behavior of different components is analyzed.
Journal Article