1.Research progress on biocomposites based on bioactive glass.
Yu PENG ; Liang LAN ; Junyu MU ; Sha HOU ; Lijia CHENG
Journal of Biomedical Engineering 2023;40(4):805-811
Bioactive glass (BG) has been widely used in the preparation of artificial bone scaffolds due to its excellent biological properties and non-cytotoxicity, which can promote bone and soft tissue regeneration. However, due to the brittleness, poor mechanical strength, easy agglomeration and uncontrollable structure of glass material, its application in various fields is limited. In this regard, most current researches mainly focus on mixing BG with organic or inorganic materials by freeze-drying method, sol-gel method, etc., to improve its mechanical properties and brittleness, so as to increase its clinical application and expand its application field. This review introduces the combination of BG with natural organic materials, metallic materials and non-metallic materials, and demonstrates the latest technology and future prospects of BG composite materials through the development of scaffolds, injectable fillers, membranes, hydrogels and coatings. The previous studies show that the addition of BG improves the mechanical properties, biological activity and regeneration potential of the composites, and broadens the application of BG in the field of bone tissue engineering. By reviewing the recent BG researches on bone regeneration, the research potential of new materials is demonstrated, in order to provide a reference for future related research.
Bone Regeneration
;
Bone and Bones
;
Freeze Drying
;
Glass
;
Hydrogels
2.Research progress on medical image dataset expansion methods.
Ying CHEN ; Hongping LIN ; Wei ZHANG ; Longfeng FENG ; Cheng ZHENG ; Taohui ZHOU ; Zhen YI ; Lan LIU
Journal of Biomedical Engineering 2023;40(1):185-192
Computer-aided diagnosis (CAD) systems play a very important role in modern medical diagnosis and treatment systems, but their performance is limited by training samples. However, the training samples are affected by factors such as imaging cost, labeling cost and involving patient privacy, resulting in insufficient diversity of training images and difficulty in data obtaining. Therefore, how to efficiently and cost-effectively augment existing medical image datasets has become a research hotspot. In this paper, the research progress on medical image dataset expansion methods is reviewed based on relevant literatures at home and abroad. First, the expansion methods based on geometric transformation and generative adversarial networks are compared and analyzed, and then improvement of the augmentation methods based on generative adversarial networks are emphasized. Finally, some urgent problems in the field of medical image dataset expansion are discussed and the future development trend is prospected.
Humans
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Diagnosis, Computer-Assisted
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Diagnostic Imaging
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Datasets as Topic
3.A survey of loss function of medical image segmentation algorithms.
Ying CHEN ; Wei ZHANG ; Hongping LIN ; Cheng ZHENG ; Taohui ZHOU ; Longfeng FENG ; Zhen YI ; Lan LIU
Journal of Biomedical Engineering 2023;40(2):392-400
Medical image segmentation based on deep learning has become a powerful tool in the field of medical image processing. Due to the special nature of medical images, image segmentation algorithms based on deep learning face problems such as sample imbalance, edge blur, false positive, false negative, etc. In view of these problems, researchers mostly improve the network structure, but rarely improve from the unstructured aspect. The loss function is an important part of the segmentation method based on deep learning. The improvement of the loss function can improve the segmentation effect of the network from the root, and the loss function is independent of the network structure, which can be used in various network models and segmentation tasks in plug and play. Starting from the difficulties in medical image segmentation, this paper first introduces the loss function and improvement strategies to solve the problems of sample imbalance, edge blur, false positive and false negative. Then the difficulties encountered in the improvement of the current loss function are analyzed. Finally, the future research directions are prospected. This paper provides a reference for the reasonable selection, improvement or innovation of loss function, and guides the direction for the follow-up research of loss function.
Algorithms
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Image Processing, Computer-Assisted
4.Optic cup and disc segmentation model based on linear attention and dual attention.
Zijun LAN ; Jun XIE ; Yan GUO ; Zhe ZHANG ; Bin SUN
Journal of Biomedical Engineering 2023;40(5):920-927
Glaucoma is one of blind causing diseases. The cup-to-disc ratio is the main basis for glaucoma screening. Therefore, it is of great significance to precisely segment the optic cup and disc. In this article, an optic cup and disc segmentation model based on the linear attention and dual attention is proposed. Firstly, the region of interest is located and cropped according to the characteristics of the optic disc. Secondly, linear attention residual network-34 (ResNet-34) is introduced as a feature extraction network. Finally, channel and spatial dual attention weights are generated by the linear attention output features, which are used to calibrate feature map in the decoder to obtain the optic cup and disc segmentation image. Experimental results show that the intersection over union of the optic disc and cup in Retinal Image Dataset for Optic Nerve Head Segmentation (DRISHTI-GS) dataset are 0.962 3 and 0.856 4, respectively, and the intersection over union of the optic disc and cup in retinal image database for optic nerve evaluation (RIM-ONE-V3) are 0.956 3 and 0.784 4, respectively. The proposed model is better than the comparison algorithm and has certain medical value in the early screening of glaucoma. In addition, this article uses knowledge distillation technology to generate two smaller models, which is beneficial to apply the models to embedded device.
Humans
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Optic Disk/diagnostic imaging*
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Glaucoma/diagnosis*
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Algorithms
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Diagnostic Techniques, Ophthalmological
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Databases, Factual
5.Effect of enhanced recovery after surgery on postoperative function and pain in total hip arthroplasty patients with high comorbidity.
Pingwen LAN ; Ming ZHANG ; Hailong LIU ; Fuyuan DENG ; Jianjun ZHANG
Chinese Journal of Reparative and Reconstructive Surgery 2023;37(9):1081-1085
OBJECTIVE:
To investigate the effects of enhanced recovery after surgery (ERAS) on postoperative function and pain in total hip arthroplasty (THA) patients with high comorbidity.
METHODS:
Patients with THA who were admitted between January 2020 and January 2022 were selected as the study objects, and a total of 223 patients with high comorbidity met the selection criteria. Patients were randomly divided into two groups using the random envelope method. During perioperative period, 112 cases in the ERAS group were treated according to the ERAS protocol and 111 cases in the control group with the traditional protocol. There was no significant difference in gender, age, body mass index, Charlson comorbidity index, preoperative diagnosis, the type and number of the comorbidities, preoperative visual analogue scale (VAS) score between the two groups ( P>0.05). However, the Harris score of ERAS group was significantly lower than that of control group before operation ( P<0.05). Preoperative and postoperative hospital stays were recorded. The VAS score was used to evaluate the pain before operation, at 1 day after operation, at the leaving bed time, at the day after discharge, and at 2 weeks after operation. Harris score was used to evaluate hip function before operation and at 2 weeks, 1 month, 3 months, 6 months, and 12 months after operation. The incidence of complications, 30-day readmission rate, mortality rate, and patient's satisfaction were recorded.
RESULTS:
The length of preoperative hospital stay in ERAS group was significantly shorter than that in control group ( P<0.05). But there was no significant difference in the length of postoperative hospital stay between groups ( P>0.05). All patients in the two groups were followed up 12 months. The VAS score in the two groups after operation was lower than that before operation, and showed a gradually trend with the extension of time, with significant differences between different time points ( P<0.05). VAS scores of ERAS group were significantly lower than those of control group at different time points after operation ( P<0.05). The postoperative Harris scores in both groups were higher than those before operation, and showed a gradually increasing trend with the extension of time, with significant differences between different time points ( P<0.05). Harris scores of ERAS group at 2 weeks, 1 month, and 3 months after operation were significantly higher than those of control group ( P<0.05). Complications occurred in 2 cases (1.79%) of the ERAS group and 6 cases (5.41%) of the control group, with no significant difference in incidence ( P>0.05). In the control group, 1 case was readmitted within 30 days after operation, and 1 case died of severe pneumonia within 1 year of follow-up. There was no readmission or death in ERAS group, and there was no significant difference in the above indexes between the two groups ( P>0.05). At last follow-up, the satisfaction rate of patients in ERAS group was slightly higher than that in control group, but the difference was not significant ( P>0.05).
CONCLUSION
For THA patients with high comorbidity, ERAS protocol can shorten preoperative waiting time, better reduce pain, and improve hip function.
Humans
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Arthroplasty, Replacement, Hip
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Enhanced Recovery After Surgery
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Comorbidity
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Pain
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Postoperative Period
6.Preparation and antimicrobial assay of ceramic brackets coated with TiO2 thin films.
Shuai CAO ; Ye WANG ; Lin CAO ; Yu WANG ; Bingpeng LIN ; Wei LAN ; Baocheng CAO
The Korean Journal of Orthodontics 2016;46(3):146-154
OBJECTIVE: Different methods have been utilized to prevent enamel demineralization and other complications during orthodontic treatment. However, none of these methods can offer long-lasting and effective prevention of orthodontic complications or interventions after complications occur. Considering the photocatalytic effect of TiO2 on organic compounds, we hoped to synthesize a novel bracket with a TiO2 thin film to develop a photocatalytic antimicrobial effect. METHODS: The sol-gel dip coating method was used to prepare TiO2 thin films on ceramic bracket surfaces. Twenty groups of samples were composed according to the experimental parameters. Crystalline structure and surface morphology were characterized by X-ray diffraction and scanning electron microscopy, respectively; film thickness was examined with a surface ellipsometer. The photocatalytic properties under ultraviolet (UV) light irradiation were analyzed by evaluating the degradation ratio of methylene blue (MB) at a certain time. Antibacterial activities of selected thin films were also tested against Lactobacillus acidophilus and Candida albicans. RESULTS: Films with 5 coating layers annealed at 700℃ showed the greatest photocatalytic activity in terms of MB decomposition under UV light irradiation. TiO2 thin films with 5 coating layers annealed at 700℃ exhibited the greatest antimicrobial activity under UV-A light irradiation. CONCLUSIONS: These results provide promising guidance in prevention of demineralization by increasing antimicrobial activities of film coated brackets.
Candida albicans
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Ceramics*
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Crystallins
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Dental Enamel
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Esthetics
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Hope
;
Lactobacillus acidophilus
;
Methods
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Methylene Blue
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Microscopy, Electron, Scanning
;
Ultraviolet Rays
;
X-Ray Diffraction
7.Positioning analysis of the Yq11 deletion in a patient with azoospermia.
Xiang-ong TU ; Feng-ua LAN ; Zhong-ong ZHU
Chinese Journal of Medical Genetics 2008;25(2):203-205
<p>OBJECTIVETo locate the deletion region of an azoospermic patient with a large deletion on his Y chromosome long arm.p><p>METHODSMultiplex polymerase chain reaction was used to amplify fifteen sequence tagged sites (STS), namely sY84, sY86, sY87 in AZFa, sY102, sY117, sY118, sY119, sY115, DYS132, DYS383, sY1015, sY121, sY125, sY127, sY129 and sY134 in AZFb, sY152 in AZFd, sY1258, sY1291, sY254, sY255, sY158 and sY1201 in AZFc, and sY160 in Yq12.p><p>RESULTSOnly sY84, sY86, sY87, sY102, sY117, sY118, sY119, sY115 and DYS132 could be amplified while the others were negative. The breakpoints were found to locate in an area between AZFb sY115 and DYS383 spanning 8577.p><p>CONCLUSIONThis study provided the exact breakpoints on Y chromosome AZF region in the patient.p>
Adult
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Azoospermia
;
genetics
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Chromosome Deletion
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Chromosomes, Human, Y
;
genetics
;
Humans
;
Male
8.Hereditary neuropathy with liability to pressure in a family with four affected members.
Jian-yu ZHANG ; Lan PENG ; Dong-bai LIU ; Tingting TAO
Chinese Journal of Medical Genetics 2012;29(6):735-735
Adult
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Aged
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Arthrogryposis
;
diagnosis
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Female
;
Hereditary Sensory and Motor Neuropathy
;
diagnosis
;
Humans
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Male
;
Middle Aged
;
Pedigree
;
Young Adult
9.Establishment of median values for second trimester maternal serum biomarkers in Weihai region.
Xin-qiang LAN ; Shu-hui WANG ; Yu-zhi DENG
Chinese Journal of Medical Genetics 2012;29(6):693-696
<p>OBJECTIVETo establish the median values for second trimester biomarkers in Weihai region, and to assess its value for improving the performance and efficiency of prenatal screening.p><p>METHODSMaternal serum alpha-fetoprotein (AFP) and free beta human chorionic gonadotropin (Free beta-hCG) were determined for 24 400 pregnant women at 105 to 146 gestational days. A regression equation was derived after adjusting for different gestational ages. The median values were further adjusted with body weight.p><p>RESULTSThe median values of AFP and Free beta-hCG were respectively 6% and 24% higher than those embedded in a 2T software. After adjusting with gestational age and weight, there is a significant difference in multiple of the median (MoM) of serum biomarkers between local population and that embedded in the 2T model.p><p>CONCLUSIONTo establish the median values for different gestational ages for local region may help to improve the efficiency of prenatal screening.p>
Adult
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Biomarkers
;
blood
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Chorionic Gonadotropin, beta Subunit, Human
;
blood
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Female
;
Humans
;
Pregnancy
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Pregnancy Outcome
;
Pregnancy Trimester, Second
;
blood
;
Reference Values
;
Young Adult
10.Polymorphisms of four microsatellite markers tightly linked with polycystic kidney disease 2 gene in Chinese.
Lan DING ; Yan SUN ; Sizhong ZHANG ; Hongyuan ZHOU ; Yan PENG
Chinese Journal of Medical Genetics 2002;19(1):33-36
<p>OBJECTIVETo investigate the polymorphisms of four microsatellites, D4S1534, D4S1563, D4S423 and D4S414, which are tightly linked to polycystic kidney disease 2 (PKD2) gene, and hence to provide a basis for studying the heterogeneity of adult polycystic kidney disease (APKD).p><p>METHODSAn analysis on the DNA of some unrelated Chinese people was performed using polymerase chain reaction (PCR), polyacrylamide gel electrophoresis (PAGE) and silver staining.p><p>RESULTSIn Chinese Hans, there are 11 alleles of D4S1534, and their sizes are 142-162 bp 14 alleles of D4S1563, 205-235 bp 17 alleles of D4S423, 103-135 bp; and 15 alleles of D4S414, 236-264 bp. The polymorphism information contents of the four microsatellites are 0.872, 0.844, 0.921 and 0.871 respectively.p><p>CONCLUSIONIn the Chinese Han people studied above, the four microsatellite markers that have many alleles are highly polymorphic genetic markers and may serve as the data of population genetics, suggesting that all four microsatellites could be used in studies on heterogeneity of APKD, linkage analysis of APKD and forensic personal identification.p>
Alleles
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Asian Continental Ancestry Group
;
genetics
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Genetic Linkage
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Genetic Predisposition to Disease
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Humans
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Membrane Proteins
;
genetics
;
Microsatellite Repeats
;
genetics
;
Polycystic Kidney Diseases
;
genetics
;
Polymorphism, Genetic
;
TRPP Cation Channels