1.A low-dose CT reconstruction method using sub-pixel anisotropic diffusion.
Shizhou TANG ; Ruolan SU ; Shuting LI ; Zhenzhen LAI ; Jinhong HUANG ; Shanzhou NIU
Journal of Southern Medical University 2025;45(1):162-169
OBJECTIVES:
We present a new low-dose CT reconstruction method using sub-pixel and anisotropic diffusion.
METHODS:
The sub-pixel intensity values and their second-order differences were obtained using linear interpolation techniques, and the new gradient information was then embedded into an anisotropic diffusion process, which was introduced into a penalty-weighted least squares model to reduce the noise in low-dose CT projection data. The high-quality CT image was finally reconstructed using the classical filtered back-projection (FBP) algorithm from the estimated data.
RESULTS:
In the Shepp-Logan phantom experiments, the structural similarity (SSIM) index of the CT image reconstructed by the proposed algorithm, as compared with FBP, PWLS-Gibbs and PWLS-TV algorithms, was increased by 28.13%, 5.49%, and 0.91%, the feature similarity (FSIM) index was increased by 21.08%, 1.78%, and 1.36%, and the root mean square error (RMSE) was reduced by 69.59%, 18.96%, and 3.90%, respectively. In the digital XCAT phantom experiments, the SSIM index of the CT image reconstructed by the proposed algorithm, as compared with FBP, PWLS-Gibbs and PWLS-TV algorithms, was increased by 14.24%, 1.43% and 7.89%, the FSIM index was increased by 9.61%, 1.78% and 5.66%, and the RMSE was reduced by 26.88%, 9.41% and 18.39%, respectively. In clinical experiments, the SSIM index of the image reconstructed using the proposed algorithm was increased by 19.24%, 15.63% and 3.68%, the FSIM index was increased by 4.30%, 2.92% and 0.43%, and the RMSE was reduced by 44.60%, 36.84% and 15.22% in comparison with FBP, PWLS-Gibbs and PWLS-TV algorithms, respectively.
CONCLUSIONS
The proposed method can effectively reduce the noises and artifacts while maintaining the structural details in low-dose CT images.
Tomography, X-Ray Computed/methods*
;
Algorithms
;
Phantoms, Imaging
;
Anisotropy
;
Image Processing, Computer-Assisted/methods*
;
Humans
;
Radiation Dosage
2.A low-dose CT image restoration method based on central guidance and alternating optimization.
Xiaoyu ZHANG ; Hao WANG ; Dong ZENG ; Zhaoying BIAN
Journal of Southern Medical University 2025;45(4):844-852
OBJECTIVES:
We propose a low-dose CT image restoration method based on central guidance and alternating optimization (FedGP).
METHODS:
The FedGP framework revolutionizes the traditional federated learning model by adopting a structure without a fixed central server, where each institution alternatively serves as the central server. This method uses an institution-modulated CT image restoration network as the core of client-side local training. Through a federated learning approach of central guidance and alternating optimization, the central server leverages local labeled data to guide client-side network training to enhance the generalization capability of the CT imaging model across multiple institutions.
RESULTS:
In the low-dose and sparse-view CT image restoration tasks, the FedGP method showed significant advantages in both visual and quantitative evaluation and achieved the highest PSNR (40.25 and 38.84), the highest SSIM (0.95 and 0.92), and the lowest RMSE (2.39 and 2.56). Ablation study of FedGP demonstrated that compared with FedGP(w/o GP) without central guidance, the FedGP method better adapted to data heterogeneity across institutions, thus ensuring robustness and generalization capability of the model in different imaging conditions.
CONCLUSIONS
FedGP provides a more flexible FL framework to solve the problem of CT imaging heterogeneity and well adapts to multi-institutional data characteristics to improve generalization ability of the model under diverse imaging geometric configurations.
Tomography, X-Ray Computed/methods*
;
Humans
;
Radiation Dosage
;
Image Processing, Computer-Assisted/methods*
;
Algorithms
3.Oroxylin A inhibits UVB-induced non-melanoma skin cancer by regulating XPA degradation.
Renjie DOU ; Jiarui SUN ; Hang YANG ; Yufen ZHENG ; Kang YUAN ; Lei QIANG ; Run MA ; Yunyao LIU
Chinese Journal of Natural Medicines (English Ed.) 2025;23(6):742-753
Oroxylin A (OA), a natural compound extracted from Scutellaria baicalensis, demonstrates preventive potential against ultraviolet B (UVB)-induced non-melanoma skin cancer (NMSC), the most prevalent cancer worldwide with increasing incidence. Utilizing SKH-1 hairless mice exposed to UVB, this study showed that OA delayed NMSC onset and alleviated acute skin damage. Mechanistic investigations revealed its dual action: inhibiting inflammation and enhancing nucleotide excision repair (NER) by stabilizing XPA, a crucial deoxyribonucleic acid (DNA) repair protein. This stabilization occurred through OA's interaction with glucose-regulated protein 94 (GRP94), which disrupted murine double minute 2 (MDM2)-mediated XPA ubiquitination and proteasomal degradation. By maintaining XPA levels, OA expedited photoproduct clearance and diminished genomic instability, ultimately impeding NMSC development. These findings suggest OA as a promising chemopreventive agent targeting the GRP94/MDM2-XPA axis to counteract UVB-induced carcinogenesis.
Animals
;
Ultraviolet Rays/adverse effects*
;
Skin Neoplasms/prevention & control*
;
Flavonoids/pharmacology*
;
Mice
;
Xeroderma Pigmentosum Group A Protein/genetics*
;
Humans
;
Proto-Oncogene Proteins c-mdm2/genetics*
;
DNA Repair/drug effects*
;
Scutellaria baicalensis/chemistry*
;
Mice, Hairless
;
Skin/radiation effects*
4.Clinical study on low-energy semiconductor laser treatment in the promotion of wound healing after maxillofacial fracture surgery.
Maojing XIONG ; Lu YANG ; Liyuan MA ; Lei LIU ; Bo YANG
West China Journal of Stomatology 2025;43(1):68-75
OBJECTIVES:
This study aims to evaluate the clinical effect of low-energy semiconductor laser treatment on the promotion of wound healing after maxillofacial fracture surgery.
METHODS:
A prospective randomized controlled study was conducted. Patients with maxillofacial fractures who were hospitalized in the Department of Trauma and Plastic Surgery, West China Hospital of Stomatology, Sichuan University, from August 2021 to June 2023 were selected as the study subjects and randomly divided into experimental and control groups. The experimental group was treated with a low-energy semiconductor laser once a day for six consecutive days after daily routine dressing change on the first day after surgery. The control group only underwent routine dressing change treatment and did not receive low-energy semiconductor laser treatment. Wound healing times, wound healing conditions, modified Stony Brook scar evaluation scale (mSBSES) scores, pain indices, and wound infection rates were compared between the two groups.
RESULTS:
A total of 211 patients were included in this study. A total of 104 and 107 cases comprised the experimental and control groups, respectively. A total of 128 males and 83 females were included. After low-energy semiconductor laser treatment, the facial skin wound healing time of the experimental group was found to be significantly shorter than that of the control group (P<0.05). Moreover, the wound grade A healing rate of the experimental group was higher than that of the control group on the seventh day after surgery (P<0.05). Among postoperative facial skin wound evaluation indices, the mSBSES scores of the experimental group at all observation points were higher than those of the control group (P<0.05), and the scores of the experimental group were higher than those of the control group in terms of wound width reduction, height reduction, color lightening, and incision line loss (P<0.05). In postoperative wound pain evaluation, the pain index of the experimental group after low-energy semiconductor laser treatment was significantly lower than that of the control group (P<0.05). No significant difference in wound infection rates was found between the two groups (P>0.05).
CONCLUSIONS
For facial skin wounds in maxillofacial fracture surgery, low-energy semiconductor laser treatment can effectively promote wound healing, improve wound healing quality, fade scars, and relieve wound pain.
Humans
;
Wound Healing/radiation effects*
;
Male
;
Female
;
Lasers, Semiconductor/therapeutic use*
;
Prospective Studies
;
Adult
;
Middle Aged
;
Low-Level Light Therapy
;
Maxillofacial Injuries/surgery*
;
Young Adult
5.Laser-assisted spatiotemporal control of Noxa expression in engineering bacteria for treating tumors.
Tingfang GAN ; Naiming ZHENG ; Huifeng LI ; Jinrui XU ; Ningning WU ; Lixin MA ; Yunhong HU
Chinese Journal of Biotechnology 2025;41(8):3199-3213
Bacterial therapy has attracted increasing attention due to its special mechanism and abundant applications. With the flourishing development of synthetic biology, therapeutic genes have been introduced into engineering bacteria to improve their antitumor efficacy. However, it is difficult to spatiotemporally control the expression of these therapeutic genes at the tumor site in vivo, thereby considerably limiting the application of engineered bacteria in tumor treatment. To resolve this problem, we constructed a temperature-responsive bacterial strain capable of triggering the expression of exogenous genes in a laser-controllable way. Noxa, a pro-apoptotic protein, is chosen to test the expression of exogenous protein and its anti-tumor effect in engineered bacteria upon laser irradiation. Firstly, Noxa was fused to the C-terminus of the bacterial outer membrane protein cytolysin A (ClyA), and then the recombinant gene fragment ClyA-Noxa was inserted into the temperature-sensitive plasmid pBV220 and the recombinant plasmid was transformed into non-pathogenic Escherichia coli MG1655. Thus, we constructed the engineering strain (TRB@Noxa) that could express Noxa on the bacterial surface. TRB@Noxa could target and colonize the tumor tissue without causing notable host toxicity. The bacterial infection triggered thrombosis in the tumor tissue, resulting in the darkness of tumor sites. In a xenograft mouse tumor model, our strategy demonstrated precise tumor targeting and strong tumor inhibition. In conclusion, we successfully constructed a new engineering bacterial strain TRB@Noxa. TRB@Noxa combined with photothermal therapy could arrest tumor growth in the absence of photosensitizers, which represents an appealing method for antitumor therapy in the future.
Escherichia coli/radiation effects*
;
Animals
;
Humans
;
Lasers
;
Mice
;
Proto-Oncogene Proteins c-bcl-2/biosynthesis*
;
Neoplasms/therapy*
;
Genetic Engineering
;
Cell Line, Tumor
;
Escherichia coli Proteins/genetics*
6.Application of Multi-Model Adaptive Statistical Iterative Reconstruction-Veo in Ultra-Low Dose Chest CT Examination of Children in Plateau Area.
Xian-Tao WANG ; Rui-Ting BAI ; CIDANWANGJIU ; SUOLANGNIMA ; NIMAZHUOGA ; Bai-Yan SU
Acta Academiae Medicinae Sinicae 2025;47(1):29-34
Objective To explore the application value of multi-model adaptive statistical iterative reconstruction-Veo (ASiR-V) in ultra-low dose chest CT examination of children in the plateau area. Methods The children who underwent chest CT examination in Xizang Autonomous Region People's Hospital were enrolled in this study and assigned into two groups according to the scanning conditions.Group A underwent scanning at a tube voltage of 100 kV and ASiR-V 50% reconstruction,and group B underwent scanning at a tube voltage of 80 kV and ASiR-V 0 (Group B1) and ASiR-V 50% (Group B2) reconstruction.The image quality of each group was evaluated objectively and subjectively.The radiation dose and image quality were compared between groups. Results Groups A and B showed the volume CT dose indexes of (2.33±0.62) mGy and (0.86±0.01) mGy and the dose length products of (65.01±25.12) mGy·cm and (23.55±3.38) mGy·cm,respectively,which presented differences between groups (both P<0.001).The image noise in the bilateral upper and middle lung areas in group B2 was lower than that in group B1 but higher than that in group A (all P<0.001).There was no significant difference in image quality score of the lung window among groups (all P>0.05).Groups A,B1,and B2 had no significant differences in ascending aorta (P=0.538) or liver CT value (P=0.175) in the mediastinal window.The signal-to-noise ratios and contrast-to-noise ratios of ascending aorta and liver in group B2 were higher than those in group B1 (all P<0.001) and lower than those in group A (all P<0.05).The image quality score of the mediastinal window followed a descending order of group A>group B2>group B1 (all P<0.001)。Conclusion ASiR-V combined with low tube voltage can effectively reduce the radiation dose and guarantee the image quality of chest CT of children in the plateau area.
Humans
;
Radiation Dosage
;
Tomography, X-Ray Computed/methods*
;
Child
;
Male
;
Female
;
Child, Preschool
;
Radiography, Thoracic/methods*
;
Infant
;
Models, Statistical
;
Image Processing, Computer-Assisted/methods*
7.Carcinoma buccal mucosa treated with definitive hypofractionated accelerated radiotherapy: a retrospective analysis of treatment outcomes.
Geethu BABU ; Rejnish RAVIKUMAR ; Malu RAFI ; Zuzaki SHARAFUDDIN ; Arun SHANKAR S ; Preethi Sara GEORGE ; Cessal Thommachan KAINICKAL ; Ramadas KUNNAMBATH
Singapore medical journal 2025;66(7):368-372
INTRODUCTION:
Oral cancer is a major public health concern in India. Both conventional and altered fractionation radiotherapy schedules have been used in curative treatment of oral cancer. This study aimed to retrospectively evaluate the clinical profile and treatment outcomes of patients with carcinoma buccal mucosa who underwent treatment with definitive hypofractionated accelerated radiotherapy.
METHODS:
A total of 517 patients treated from January 2011 to December 2016 were eligible for the analysis. All patients were treated with definitive hypofractionated accelerated radiotherapy schedule of 5,250 cGy in 15 fractions over 3 weeks. Survival estimates were generated using the Kaplan-Meier method.
RESULTS:
At a median follow-up of 77.4 months, 473 (91.5%) patients attained complete remission with radiation therapy. The 5-year disease-free survival (DFS) and overall survival (OS) rates were 69% and 80.5%, respectively. The 5-year OS for stage I, II, III and IVa tumours was 80.3%, 84.4%, 81.4% and 73.7%, respectively, and the DFS was 75.7%, 73.2%, 69.6% and 60.2%, respectively. Age >50 years was found to be a significant factor affecting DFS ( P = 0.026) and OS ( P = 0.048) in multivariate analysis. Fifty-three (10.3%) patients developed osteoradionecrosis of the mandible.
CONCLUSION
Excellent outcome could be achieved in less-aggressive, low-volume carcinoma of the buccal mucosa with radical accelerated hypofractionated radiotherapy. A radiotherapy schedule over a 3-week period is useful in high-volume centres.
Humans
;
Retrospective Studies
;
Male
;
Female
;
Middle Aged
;
Mouth Neoplasms/mortality*
;
Mouth Mucosa/radiation effects*
;
Treatment Outcome
;
Aged
;
Adult
;
Radiation Dose Hypofractionation
;
Disease-Free Survival
;
India
;
Kaplan-Meier Estimate
;
Dose Fractionation, Radiation
;
Aged, 80 and over
8.Morphological and physiological responses to shading caused by dense planting or light quality modulation in shade-tolerant plant Anoectochilus roxburghii.
Xiao-Lei GUO ; Li-Chun ZHOU ; Ming-Jie LI ; Zhong-Yi ZHANG ; Li GU
China Journal of Chinese Materia Medica 2025;50(10):2648-2657
The balance between growth and defense in response to nearby or canopy shading in heliotropic plants has been deeply understood. However, the adaptive traits developed by shade-tolerant plants through long-term evolution remain unclear. In this study, the typical shade-tolerant medicinal plant Anoectochilus roxburghii was used as the experimental material.(1) Different planting densities were set, including 8 cm(row spacing) × 8 cm(plant spacing), 6 cm × 6 cm, 4 cm × 4 cm, and 2 cm × 2 cm, to monitor the individual plant responses to nearby shading.(2) Different light environments, including blue light∶red light=3∶2(B3R2), blue light∶red light∶far-red light=3∶2∶1(B3R2FR1), blue light∶red light∶far-red light=3∶2∶2(B3R2FR2), and blue light∶red light∶far-red light=3∶2∶4(B3R2FR4), were set to monitor the morphological and physiological changes in plants in response to actual shading conditions. The results showed that:(1) Moderate increases in planting density helped optimize morphological traits such as stem diameter and leaf area. This not only slightly increased biomass but also significantly improved SOD activity in both leaves and stems, as well as lignin content in stems, thereby enhancing the plant's defense capabilities.(2) Increasing the far-red light in the light environment negatively regulated the plant height of A. roxburghii, which was contrary to the typical shade-avoidance response observed in heliotropic plants. However, it significantly enhanced SOD and POD activity in both stems and leaves, as well as lignin content in stems. Furthermore, it reduced the incidence and disease index of stalk rot, effectively defending against biotic stress. Therefore, the shade-tolerant plant A. roxburghii has specific adaptive strategies for shading conditions. Reasonable dense planting or light environment modulation can synergistically improve yield, medicinal quality, and resistance of A. roxburghii. This study provides a theoretical foundation and technical support for optimizing the regional deployment and cultivation strategies of ecological planting for Chinese medicinal materials.
Orchidaceae/genetics*
;
Light
;
Plant Leaves/physiology*
;
Sunlight
;
Adaptation, Physiological/radiation effects*
;
Plant Proteins/genetics*
9.Controllability and predictability of riboflavin-ultraviolet A collagen cross-linking: advances in experimental techniques and theoretical research.
Xiaona LIU ; Xiaona LI ; Weiyi CHEN
Journal of Biomedical Engineering 2025;42(1):212-218
Riboflavin-ultraviolet A (UVA) collagen cross-linking has not only achieved good clinical efficacy in the treatment of corneal diseases such as dilatation keratopathy, bullae keratopathy, infectious keratopathy, and in the combined treatment of corneal refractive surgeries, but also its efficacy and safety in scleral collagen cross-linking have been initially confirmed. To better promote the application of cross-linking in the clinical treatment of corneal and scleral diseases, exploring controllability and predictability of the surgical efficacy are both important for evaluating the surgical efficacy and personalized precision treatment. In this paper, the progress on the cross-linking depth of riboflavin-UVA collagen cross-linking, and its relationship with the cross-linking effect will be reviewed. It will provide the reference for further application of this procedure in ophthalmology clinics.
Riboflavin/pharmacology*
;
Humans
;
Collagen/radiation effects*
;
Ultraviolet Rays
;
Cross-Linking Reagents
;
Corneal Diseases/drug therapy*
;
Photosensitizing Agents/therapeutic use*
10.Advances in low-dose cone-beam computed tomography image reconstruction methods based on deep learning.
Jiangyuan SHI ; Ying SONG ; Guangjun LI ; Sen BAI
Journal of Biomedical Engineering 2025;42(3):635-642
Cone-beam computed tomography (CBCT) is widely used in dentistry, surgery, radiotherapy and other medical fields. However, repeated CBCT scans expose patients to additional radiation doses, increasing the risk of secondary malignant tumors. Low-dose CBCT image reconstruction technology, which employs advanced algorithms to reduce radiation dose while enhancing image quality, has emerged as a focal point of recent research. This review systematically examined deep learning-based methods for low-dose CBCT reconstruction. It compared different network architectures in terms of noise reduction, artifact removal, detail preservation, and computational efficiency, covering three approaches: image-domain, projection-domain, and dual-domain techniques. The review also explored how emerging technologies like multimodal fusion and self-supervised learning could enhance these methods. By summarizing the strengths and weaknesses of current approaches, this work provides insights to optimize low-dose CBCT algorithms and support their clinical adoption.
Cone-Beam Computed Tomography/methods*
;
Deep Learning
;
Humans
;
Algorithms
;
Image Processing, Computer-Assisted/methods*
;
Radiation Dosage
;
Artifacts

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