Novel chlorinated and nitrogenated azaphilones with cytotoxic activities from the marine algal-derived fungus Chaetomium globosum 2020HZ23.

Two novel chlorinated and nitrogenated azaphilones, namely N-butyl-2-aza-2-deoxychaetoviridin A (1) and N-hexyl-2-aza-2-deoxychaetoviridin A (2), along with a previously identified analogue, chaetoviridin A (3), were successfully obtained from Chaetomium globosum 2020HZ23, a marine algal-sourced endophytic fungus. The planar structures as well as the absolute configurations of these new metabolites were determined utilizing a synergistic approach that involved both spectroscopic techniques (1D/2D NMR and HRESIMS) and Density Functional Theory (DFT) calculations. Each compound was subject to in vitro cytotoxicity evaluation toward the A549 cancer cell line. Both compounds 1 and 2 demonstrated significant cytotoxicity, as evidenced by their respective IC50 values of 13.6 and 17.5 µM. Furthermore, 1 and 2 demonstrated potent cell migration inhibition, which elevated with increasing dose concentration. In contrast, compound 3 exhibited less cytotoxic activity relative to 1 and 2, suggesting that the cytotoxic potency escalates with N-substitution at the C-2 position and the introduction of a side chain. This finding could offer implications for future studies aimed at designing and refining lead compounds within this class.

A novel distance of intuitionistic trapezoidal fuzzy numbers and its-based prospect theory algorithm in multi-attribute decision making model.

The aim of this paper is to develop a new decision making method considering decision makers' psychological behavior for multi-attribute decision making problem under intuitionistic trapezoidal fuzzy environment. We first put forward a new distance measure of intuitionistic trapezoidal fuzzy numbers. Then combining with cumulative prospect theory, we develop a novel decision making method, which can consider risk attitude of decision makers. Finally, an example is given to demonstrate the effectiveness and practicability of the proposed method.

Magnetic Resonance Image Denoising Algorithm Based on Cartoon, Texture, and Residual Parts.

Magnetic resonance (MR) images are often contaminated by Gaussian noise, an electronic noise caused by the random thermal motion of electronic components, which reduces the quality and reliability of the images. This paper puts forward a hybrid denoising algorithm for MR images based on two sparsely represented morphological components and one residual part. To begin with, decompose a noisy MR image into the cartoon, texture, and residual parts by MCA, and then each part is denoised by using Wiener filter, wavelet hard threshold, and wavelet soft threshold, respectively. Finally, stack up all the denoised subimages to obtain the denoised MR image. The experimental results show that the proposed method has significantly better performance in terms of mean square error and peak signal-to-noise ratio than each method alone.

Study on in vitro performance verification protocol for left ventricular assist device.

OBJECTIVE: In vitro performance verification of ventricular assist devices using a mock circulatory loop is a prominent step to guarantee the system responses and the device performance and safety before the in vivo tests and ultimately clinical trials. METHODS: In this article, we performed a comprehensive literature research to establish a verification matrix consisting of 12 test cases, defined by a set of physiological parameters which are commonly used to characterize a physiological condition. The clinical hemodynamic indicators for defining successful mechanical support were used as the acceptance criteria. A mock circulatory loop was customized to simulate the test cases, and a full verification protocol was described in details. An example left ventricular assist device was incorporated in the loop to accomplish a standard ventricular assist device performance verification. RESULT: The test cases based on clinical data with sufficient safety margin represent our understanding in defining the extremes of operation. The mock circulatory loop was capable of generating the test conditions in the verification matrix and reproducing the Frank-Starling law of the native heart. The effect of the left ventricular assist device assistance (characterized by the total systemic flow, mean aortic pressure, and left atrial pressure) was well verified by the proposed protocol and acceptance criteria. CONCLUSION: To date, all left ventricular assist devices made in China have been evaluated according this protocol and some of them have entered the clinical trial stage. We are closely observing the clinical data in order to further improve the performance of the platform and encourage more advances in mechanical circulatory assist devices.

[The Role and Requirement of Datasets in the Quality Control of Artifcial Intelligence Medical Device].

Artificial intelligence is a blooming branch of medical device. Its development and quality control all rely on high quality clinical data. Since there is no established standard or guidance yet, it is important to study how to build and utilize a dataset appropriately and scientifically, especially for the decrease of clinical trial expense. With reference to the current status of premarket review and related guidance in developed countries, this paper analyzes the role and requirement of datasets in the quality control of AI medical device, providing useful information for regulation agencies and the development of public datasets for AI.

A measurement system of high-temperature oxidation environment with ultrasonic Ir0.6Rth0.4 alloy thermometry.

Iridium-rhodium is generally applied as a thermocouple material, with max operating temperature about 2150 °C. In this study, a ultrasonic temperature measurement system was designed by using Iridium-rhodium (60%Ir-40%Rh) alloy as an acoustic waveguide sensor material, and the system was preliminarily tested in a high-temperature oxidation environment. The result of ultrasonic temperature measurement shows that this system can indeed work stably in high-temperature oxidation environments. The relationship between temperature and delay time of ultrasonic thermometry up to 2200 °C was illustrated. Iridium-rhodium materials were also investigated in order to fully elucidate the proposed waveguide sensor's performance in a high-temperature oxidation environment. This system lays a foundation for further application of high-temperature measurement.

[Analysis of the National Quality Inspection for Medical Devices].

This paper analyses overall situation of the national quality inspection for medical devices in recent 13 years. The statistics cover the inspected varieties, sampling quantity and quality status. The achievements and suggestions are provided, which are helpful for future work.

[Establishment and evaluation of intraocular lens loop support force test platform].

OBJECTIVE: Establish the test platform of the intraocular lens loop, and the platform was evaluated through the experiment. METHODS: The intraocular lens loop test platform is made up with three models. The different intraocular lens haptics support force can be completed by replacing different sample holder model. RESULTS: The standard deviation and the coefficient of variation were calculated through the result of the fifteen samples. The standard deviation was 0.04 mN, and the coefficient of variation was 0.66%. The two values were in the acceptable range. CONCLUSIONS: The platform was so stabilizing that it could be used to test support force of IOL loop. The different shapes of IOL could be tested on the platform through the replacement of the holder model.

[Realization of DICOM medical image compression technology].

This paper introduces the implement method of DICOM medical image compression technology, The image part of DICOM files are extracted and converted to BMP format. The non-image information in DICOM file are stored into the text. When the final image of JPEG standard and non-image information are encapsulated to DICOM format images, it realizes the compression of medical image, which is beneficial to the image storage and transmission.

[Cluster application in PACS system].

How to use clustering techniques in PACS system is introduced. Two kinds of cluster solution to configure PACS system is proposed.

[Study on the supervision of in-vitro diagnostic reagents].

The regulatory history and status of in vitro diagnostic reagents (IVD) at home and abroad are introduced. Suggestions are also provided on the administration of IVD.

A novel magnetic resonance-positive emission image registration based on morphology.

Structures were obtained from images with morphological characteristics to register with voxel-based method. We applied simple morphological operations to obtain human brain cortex and chose normalized mutual information as similarity measure for the geometric alignment of PET and MR images. Evaluation used nine patients, and the results showed that sub-voxel accuracy was achieved and the registration process was significantly more rapid. Thus this new automated multi-modality registration method is more robust and has high accuracy.

Multidistortion-invariant image recognition with radial harmonic Fourier moments.

We propose radial harmonic Fourier moments, which are shifting, scaling, rotation, and intensity invariant. Compared with Chebyshev-Fourier moments, the new moments have superior performance near the origin and better ability to describe small images in terms of image-reconstruction errors and noise sensitivity. A multidistortion-invariant pattern-recognition experiment was performed with radial harmonic Fourier moments.

[Method of multi-resolution 3D image registration by mutual information].

Maximization of mutual information is a powerful criterion for 3D medical image registration, allowing robust and fully accurate automated rigid registration of multi-modal images in a various applications. In this paper, a method based on normalized mutual information for 3D image registration was presented on the images of CT, MR and PET. Powell's direction set method and Brent's one-dimensional optimization algorithm were used as optimization strategy. A multi-resolution approach is applied to speedup the matching process. For PET images, pre-procession of segmentation was performed to reduce the background artefacts. According to the evaluation by the Vanderbilt University, Sub-voxel accuracy in multi-modality registration had been achieved with this algorithm.