Breast ultrasound image despeckling using multi-filtering DFrFT and adaptive fast BM3D.

Improving the quality of breast ultrasound images is of great significance for clinical diagnosis which can greatly boost the diagnostic accuracy of ultrasonography. However, due to the influence of ultrasound imaging principles and acquisition equipment, the collected ultrasound images naturally contain a large amount of speckle noise, which leads to a decrease in image quality and affects clinical diagnosis. To overcome this problem, we propose an improved denoising algorithm combining multi-filter DFrFT (Discrete Fractional Fourier Transform) and the adaptive fast BM3D (Block Matching and 3D collaborative filtering) method. Firstly, we provide the multi-filtering DFrFT method for preprocessing the original breast ultrasound image so as to remove some speckle noise early in fractional transformation domain. Based on the fractional frequency spectrum characteristics of breast ultrasound images, three types of filters are designed correspondingly in low, medium, and high frequency domains. And by integrating filtered images, the enhanced images are obtained which not only remove some speckle noise in background but also preserve the details of breast lesions. Secondly, for further enhancing the image quality on the basis of multi-filter DFrFT, we propose the adaptive fast BM3D method by introducing the DBSCAN-based super pixel segmentation to block matching process, which utilizes super pixel segmentation labels to provide a reference on how similar it is between target block and retrieval blocks. It reduces the number of blocks to be retrieved and make the matched blocks with more similar features. At last, the local noise parameter estimation is also adopted in the hard threshold filtering process of traditional BM3D algorithm to achieve local adaptive filtering and further improving the denoising effect. The synthetic data and real breast ultrasound data examples show that this combined method can improve the speckle suppression level and keep the fidelity of structure effectively without increasing time cost.

Analysis of etiology and complications in children with stage 5 chronic kidney disease / 中华儿科杂志

Objective: To investigate the etiology, complications, and prognostic factors of stage 5 chronic kidney disease (CKD5) in children. Methods: A case series study was conducted to retrospectively analyze the general situation, clinical manifestations, laboratory tests, genetic testing, and follow-up data (until October 2022) of 174 children with CKD5 who were diagnosed and hospitalized at the Children's Hospital of Chongqing Medical University from April 2012 to April 2021. The characteristics of complications in the children were compared based on age, gender, and etiology. Based on the presence or absence of left ventricular hypertrophy (LVH), patients were divided into LVH group and non LVH group for analyzing the influencing factors of cardiovascular disease. Patients were also divided into death group and survival group, peritoneal dialysis group and hemodialysis group based on the follow-up data for analyzing the prognostic factors. The chi-square test, independent sample t-test, Fisher exact probability test, Mann-Whitney U test and Kruskal Wallis test were used to analyze data among different groups. Multivariate Logistic regression analysis was used to identify the prognostic factors. Results: A total of 174 children with CKD5 were enrolled in the study (96 boys and 78 girls), aged 11.2 (8.2, 13.0) years. Congenital kidney and urinary tract malformations (CAKUT) were the most common causes of the CKD5 (84 cases, 48.3%), followed by glomerular diseases (83 cases, 47.7%), and among which 28 cases (16.1%) were hereditary glomerular diseases. The common complications of CKD5 included anemia (98.2%, 165/168), mineral and bone disorder in chronic kidney disease (CKD-MBD) (97.7%, 170/174), lipid metabolism disorders (87.5%, 63/72), hypertension (81.4%, 127/156) and LVH (57.6%,57/99). The incidences of hypertension in primary glomerular disease were higher than that in CAKUT(93.8%(30/32) vs.73.7%(56/76),χ2=5.59,P<0.05). The incidences of hypertension in secondary glomerular disease were higher than that in CAKUT and that in hereditary kidney disease (100.0%(20/20) vs. 73.7%(56/76), 68.2%(15/22), both P<0.05). The incidence of hypocalcemia in CAKUT, primary glomerular disease, and hereditary kidney disease was higher than that in secondary glomerular disease (82.1%(69/84), 88.2%(30/34), 89.3%(25/28) vs. 47.6%(10/21), χ2=10.21, 10.75, 10.80, all P=0.001); the incidence of secondary hyperparathyroidism in women was higher than that in men (80.0%(64/80) vs. 95.0%(57/60), χ2=6.58, P=0.010). The incidence of LVH in children aged 6-<12 was higher than that in children aged 12-18 (73.5%(25/34) vs. 43.1%(22/51), χ2=7.62, P=0.006). Among 113 follow-up children, the mortality rate was 39.8% (45/113). Compared to the survival group, the children in the death group had lower hemoglobin, higher blood pressure, lower albumin, lower alkaline phosphatase and higher left ventricular mass index ((67±19) vs. (75±20) g/L, 142 (126, 154) vs. 128(113, 145) mmHg(1 mmHg=0.133 kPa), (91±21) vs. (82±22) mmHg, 32 (26, 41) vs. 40 (31, 43) g/L, 151 (82, 214) vs. 215 (129, 37) U/L, 48 (38, 66) vs. 38(32, 50) g/m2.7,t=2.03, Z=2.89, t=2.70, Z=2.49, 2.79, 2.29,all P<0.05), but no independent risk factors were identified (all P>0.05). The peritoneal dialysis group had better alleviation for anemia, low calcium, and high phosphorus than the hemodialysis group ((87±22) vs. (72±16) g/L, (1.9±0.5) vs. (1.7±0.4) mmol/L, (2.2±0.7) vs. (2.8±0.9) mmol/L, t=2.92, 2.29, 2.82, all P<0.05), and the survival rate of the peritoneal dialysis group was significantly higher than that of the hemodialysis group (77.8% (28/36) vs. 48.4% (30/62), χ2=8.14, P=0.004). Conclusions: CAKUT is the most common etiology in children with CKD 5, and anemia is the most common complication. The incidence of complications in children with CKD 5 varies with age, gender and etiology. Anemia, hypertension, hypoalbuminemia, reduced alkaline phosphatase and elevated LVMI may be the prognostic factors in children with CKD5. Peritoneal dialysis may be more beneficial for improving the long-term survival rate.

Research advances on alkaloids against tuberculosis / 中草药

Tuberculosis is one of the diseases with high incidence and mortality in the world. In the face of the increasing severe challenges of tuberculosis, there is a key to fight against tuberculosis by finding new ways and new ideas to develop new anti-tuberculosis drugs. Alkaloid compounds are widely distributed in natural medicines, which have the characteristics of biodiversity, chemical structure diversity and biological activity diversity, and most alkaloids have anti-tuberculosis activity. This article reviews the research progress of the effects of alkaloids on tuberculosis and the mechanism of anti-tuberculosis in recent years, which may summarize the characteristics of different types of alkaloids against tuberculosis and provide reference for further research, development and utilization of these compounds against tuberculosis.