1.Compact Fundus Imaging System Using Shack-Hartmann Wavefront Sensing for High-speed Auto-focus
Zhe-Kai LIN ; Long CHEN ; Geng-Yong ZHENG ; Jin-Tian HUANG ; Jia-Xin DONG ; Shang-Pan YANG ; Wen-Zheng DING ; Ding-An HAN ; Xue-Hua WANG ; Ya-Guang ZENG
Progress in Biochemistry and Biophysics 2026;53(4):1076-1086
ObjectiveThe widespread adoption of portable fundus cameras for primary care and community screening is hindered by limitations in current autofocus(AF) technologies. Image-based methods relying on sharpness evaluation require iterative searches, resulting in slow convergence, while projection-based techniques are susceptible to optical artifacts and calibration errors. To address these challenges, this study introduces a novel AF system based on direct wavefront sensing, designed to deliver simultaneous high speed, high precision, and operational robustness within the compact form factor essential for portable ophthalmic devices. MethodsOur approach fundamentally reimagines the AF process by directly measuring the ocular wavefront aberration. We developed a custom portable fundus camera integrating a miniaturized Shack-Hartmann wavefront sensor (SHWS) into the optical path. An 850 nm laser diode projects a point source onto the retina via oblique illumination to minimize corneal reflections. Light scattered from this spot carries the eye’s refractive error through the imaging optics and is directed to the SHWS, positioned at a plane optically conjugate to the primary color CMOS imaging sensor. A microlens array within the SHWS samples the incident wavefront, generating a pattern of focal spots on a CCD. Real-time centroid analysis of these spots provides a map of local wavefront slopes. These measurements are processed through a singular value decomposition (SVD) algorithm to fit a Zernike polynomial basis set, enabling real-time reconstruction of the wavefront phase. The defocus component (S) is extracted from the second-order Zernike coefficients, providing a direct, quantitative measure of the refractive error in diopters. This value serves as a precise error signal in a closed-loop control system, which commands a voice-coil actuated focusing lens to its null position in a single, deterministic step, eliminating the need for iterative search algorithms. ResultsComprehensive evaluation demonstrated the system’s high performance. Testing on a calibrated model eye (OEMI-7) established a highly linear relationship between the computed defocus S and the focusing lens position across a ±20 Diopter (D) compensation range, achievable within a 5 mm mechanical travel. The system achieved a focusing precision of 0.08 D, corresponding to an 18-fold improvement over a conventional projection spot-size method tested under identical conditions. The total focus acquisition time, encompassing wavefront measurement, computation, and lens actuation, averaged under 0.5 s. Clinical validation with 25 human volunteers (50 eyes, refractive range -15 D to +10 D) confirmed practical efficacy. The wavefront-sensing AF succeeded in 92% of attempts with a mean time of 0.5 s, substantially outperforming a projection-based benchmark which achieved only a 32% success rate with an average time of 4.25 s. The system provided instantaneous directional guidance and maintained stability during minor ocular movements. Objective assessment of image quality, via amplitude contrast of retinal vasculature, showed consistent and significant enhancement following AF correction across the entire tested diopter range. ConclusionThis work successfully implements and validates a direct wavefront-sensing autofocus paradigm for portable fundus cameras. By directly quantifying and compensating for the optical defocus aberration, this method bypasses the fundamental limitations of image-processing and projection-based techniques, enabling rapid, precise, and deterministic diopter compensation. The developed system delivers an exceptional combination of a wide operational range (±20 D), high accuracy (0.08 D), fast convergence (0.5 s), and a compact physical footprint. This technology provides a practical and high-performance focusing solution capable of enhancing the reliability, throughput, and diagnostic utility of portable retinal imaging in large-scale screening applications. Future efforts will be directed towards system cost optimization and performance adaptation for diverse ocular conditions.
2.SUVmax, extraocular muscle diameter, and TRAb in assessing inflammatory activity of thyroid-associated ophthalmopathy
Weijing KONG ; Yan GUO ; Mengting HUA ; Cuishuang DING ; Hairong ZHONG ; Meiting TANG
International Eye Science 2026;26(8):1491-1495
AIM: To investigate the value of maximum standardized uptake value(SUVmax), extraocular muscle(EOM)diameter, and thyroid stimulating hormone receptor antibody(TRAb)in evaluating inflammatory activity in thyroid-associated ophthalmopathy(TAO).METHODS: TAO patients underwent orbital 99mTc-DTPA SPECT/CT imaging at the Affiliated Hospital of Panzhihua University between January 2023 and December 2024 were retrospectively enrolled. According to the clinical activity score(CAS), patients were classified into an active group and an inactive group. SUVmax and EOM were independently measured by three nuclear medicine physicians, and the mean values were used for analysis. Serum TRAb levels from TAO patients were measured using a fully automated electrochemiluminescence immunoassay analyzer. Nonparametric tests were used to compare differences between the two groups. Spearman correlation analysis was performed to assess the correlations of CAS with SUVmax, EOM, and TRAb. Using CAS as the reference standard, receiver operating characteristic(ROC)curves were plotted to evaluate the diagnostic performance of SUVmax, EOM, and TRAb, as well as their combination. Intraclass correlation coefficient(ICC)was used for reliability analysis to evaluate the consistency of SUVmax and EOM among the 3 measurers.RESULTS: A total of 99 patients(198 eyes)with TAO were enrolled in this study, including 38 males and 61 females, aged 16-74(46.92±11.84)y. The active group comprised 46 patients(92 eyes), aged 16-71(48.40±12.02)y, with 25 males and 21 females. The inactive group included 53 patients(106 eyes), aged 17-74(45.46±11.59)y, consisting of 13 males and 40 females. There were no statistically significant differences between the two groups in terms of gender and age(P>0.05). Statistically significant differences were observed in SUVmax, EOM, and TRAb. Compared with the inactive group, the active group showed higher SUVmax, EOM, and TRAb levels(all P<0.01). Correlation analysis showed that CAS was positively correlated with SUVmax, EOM, and TRAb(r=0.734, 0.622, and 0.404, respectively, all P<0.01). ROC curves were plotted using CAS as the reference standard, and the AUCs for SUVmax, EOM, TRAb, and their combined diagnosis were 0.874, 0.797, 0.715, and 0.892, respectively. The ICC of SUVmax and EOM were 0.925(95%CI: 0.901-0.948, P<0.001)and 0.943(95%CI: 0.907-0.964, P<0.001)respectively.CONCLUSION: Beyond CAS, there is a need to identify objective imaging and serological biomarkers. Measurements of SUVmax and EOM provide visualized and quantifiable tools for assessing TAO activity, and their combination with TRAb can further improve the accuracy of activity assessment.
3.Association of physical exercise with cognitive function and psychological health among primary school students
JIA Shuqi, LI Fei, LI Pan, ZHANG Wenqian, JIANG Hua, KONG Fansong, SHI Yue
Chinese Journal of School Health 2026;47(7):982-987
Objective:
To examine the association of physical activity with cognitive function and mental health among primary school students based on latent subgroup identification and dose response modeling, and to clarify cognitive-psychological profiles and the protective role of physical exercise, so as to provide evidence based support for physical exercise promoting mental health among primary school students.
Methods:
A study was conducted among 546 primary school students aged 8-12 years old from a primary school in Shanghai from March to June 2025. Physical fitness indicators, including vital capacity, 50 m sprint, sit and reach, and 1 min rope skipping were measured. Physical exercise was assessed by using the Physical Activity Rating Scale-3 (PARS-3), and mental health was assessed by using the Revised Child Anxiety and Depression Scale, 47-item version (RCADS-47). Cognitive function was assessed by using Stroop, N-back, and task-switching tasks. Latent profile analysis (LPA) was performed for cognitive-psychological health of primary school students based on seven cognitive indicators and six psychological indicators. Multivariable Logistic regression, trend test, and restricted cubic spline (RCS) analysis were used to examine associations between physical exercise and psychological highrisk status.
Results:
Five cognitive psychological health subgroups were identified:high symptom and impaired cognition group ( n =40, 7.3%), low cognition and low symptom group ( n =108, 19.8% ), and high cognition and high symptom group ( n =110, 20.2%), cognitive advantage and psychologically healthy group ( n = 272, 49.8%), and extremely high symptom and cognitively vulnerable group ( n =16, 2.9%). Among them, the high symptom and impaired-cognition group and extremely high symptom and cognitively vulnerable group were classified as psychologically high risk types. Significant differences were observed across subgroups in psychological symptoms, cognitive function, some physical fitness indicators and physical exercise level, except for body weight, body mass index, and sit and reach ( F =2.64-297.53, all P < 0.05). The results of the multivariate Logistic regression analysis indicated that high level sports, including high total volume of physical exercise, single session duration >30 min, high intensity, and frequency ≥3 times/week, was associated with lower psychological high risk status ( OR =0.20, 0.36, 0.33, 0.40, all P <0.05). Trend analysis showed that total volume of physical exercise and single session exercise duration were negatively associated with psychological high risk status among primary school students ( OR =0.98, 0.79, both P trend <0.05). RCS analysis showed no statistically significant overall or nonlinear association between total volume of physical exercise and psychological high risk status ( χ 2=2.92, 0.01, both P >0.05).
Conclusions
Cognitive-psychological health among primary school students is heterogeneous. Physical exercise is associated with psychological health improvement and may show a threshold effect, with total volume of physical exercise and single session exercise duration being the key dimensions.
4.Textual study of Baihuasheshecao (Hedyotis diffusa).
Dong-Min JIANG ; Chu-Chu ZHONG ; Pang-Chui SHAW ; Bik-San LAU ; Tai-Wai LAU ; Guang-Hao XU ; Ying ZHANG ; Zhi-Guo MA ; Hui CAO ; Meng-Hua WU
China Journal of Chinese Materia Medica 2025;50(15):4386-4396
Baihuasheshecao(Hedyotis diffusa) is a commonly used traditional Chinese medicine derived from the whole herb of H. diffusa and has been widely utilized in folk medicine. It possesses anti-tumor, antibacterial, and anti-inflammatory properties, making it one of the frequently used herbs in TCM clinical practice. However, Shuixiancao(H. corymbosa) and Xianhuaercao(H. tenelliflora), species of the same genus, are often used as substitutes for Baihuasheshecao. To substantiate the medicinal basis of Baihuasheshecao, this study systematically reviewed classical herbal texts and modern literature, examining its nomenclature, botanical origin, harvesting, processing, properties, meridian tropism, pharmacological effects, and clinical applications. The results indicate that Baihuasheshecao was initially recorded as "Shuixiancao" in Preface to the Indexes to the Great Chinese Botany(Zhi Wu Ming Shi Tu Kao). Based on its morphological characteristics and habitat description, it was identified as H. diffusa in the Rubiaceae family. Subsequent records predominantly refer to it as Baihuasheshecao as its official name. In most regions, Baihuasheshecao is recognized as the authentic medicinal material, distinct from Shuixiancao and Xianhuaercao. Baihuasheshecao is harvested in late summer and early autumn, and the dried whole plant, including its roots, is used medicinally. The standard processing method involves cutting. It is known for its effects in clearing heat, removing toxins, reducing swelling and pain, and promoting diuresis to resolve abscesses. Initially, it was mainly used for treating appendicitis, intestinal abscesses, and venomous snake bites, and later, it became a treatment for cancer. The excavation of its clinical value followed a process in which overseas Chinese introduced the herb from Chinese folk medicine to other countries. After its unique anti-cancer effects were recognized abroad, it was reintroduced to China and gradually became a crucial TCM for cancer treatment. The findings of this study help clarify the historical and contemporary uses of Baihuasheshecao, providing literature support and a scientific basis for its rational development and precise clinical application.
Humans
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China
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Drugs, Chinese Herbal/chemistry*
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Hedyotis/classification*
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Medicine, Chinese Traditional/history*
5.Mechanism of traditional Chinese medicine treatment of hepatic fibrosis by restoring circadian rhythms.
Meng-Ru ZHANG ; Ruo-Nan JIANG ; Shu-Hua XIONG ; Hong-Yan WU ; De-Song KONG ; Li CHEN
China Journal of Chinese Materia Medica 2025;50(16):4407-4414
Hepatic fibrosis is a key pathological process in the development of chronic liver disease to cirrhosis, and its core mechanism involves the activation of hepatic stellate cells(HSC) and abnormal deposition of extracellular matrix(ECM). Although existing treatments, such as antiviral drugs, can delay disease progression, they have the problem of single therapeutic targets and cannot reverse fibrosis. Accordingly, multidimensional intervention strategies are urgently needed. Recent studies have shown that circadian rhythm disorders aggravate hepatic fibrosis by regulating metabolism, immunity, and inflammation. Traditional Chinese medicine(TCM) plays a unique role in restoring the circadian clock via multi-target and holistic regulation. This paper establishes a three-dimensional network by systematically integrating biological clock, metabolism, and immunity for the first time to elucidate the scientific connotation of the theory of time-concerned treatment of TCM, and proposes a new strategy for the development of time-targeted compound prescriptions, providing innovative ideas for the treatment of hepatic fibrosis.
Humans
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Liver Cirrhosis/metabolism*
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Drugs, Chinese Herbal/therapeutic use*
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Circadian Rhythm/drug effects*
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Animals
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Medicine, Chinese Traditional
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Hepatic Stellate Cells/drug effects*
6.Effectiveness analysis of channel-assisted minimally invasive repair technique combined with flexor hallucis longus tendon transfer for Achilles tendon sleeve avulsion.
Lingtong KONG ; Zhonghe WANG ; Haoyu LIU ; Nazhi ZHAN ; Hongzhe QI ; Hua CHEN
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(3):264-270
OBJECTIVE:
To evaluate the effectiveness of the channel-assisted minimally invasive repair (CAMIR) technique combined with flexor hallucis longus (FHL) tendon transfer in the treatment of Achilles tendon sleeve avulsion.
METHODS:
A retrospective analysis was conducted on 17 patients with Achilles tendon sleeve avulsion who underwent CAMIR technique combined with FHL transfer between January 2019 and January 2023. The cohort comprised 13 males and 4 females, aged 32 to 65 years (mean, 49.7 years). Etiologies included sports-related injuries in 15 cases and blunt trauma in 2 cases. The interval from injury to surgery ranged from 4 to 368 days (median, 15 days). All patients exhibited calcification at the Achilles tendon insertion site, with 7 cases complicated by Haglund deformity. Postoperative complications were meticulously monitored, and tendon healing was assessed via MRI. Clinical outcome were evaluated using the visual analogue scale (VAS) score for pain, Tegner activity level rating scale, ankle activity score (AAS), American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, Victorian Institute of Sport Assessment-Achilles (VISA-A) score, and subjective clinical scoring systems preoperatively and at last follow-up.
RESULTS:
The operation time was 50-62 minutes (mean, 56 minutes), and the intraoperative blood loss was 5-50 mL (mean, 19.7 mL). All patients were followed up 12-67 months (mean, 38 months). No postoperative complication, such as Achilles tendon re-rupture, incision infection, deep vein thrombosis, heel raise insufficiency, or sural nerve injury, was observed. At last follow-up, MRI examination confirmed satisfactory tendon healing in all cases. Significant improvements were noted in VAS scores, Tegner activity level rating scale, AAS scores, AOFAS ankle-hindfoot scores, and VISA-A scores compared to preoperative ones ( P<0.05). At last follow-up, the subjective clinical score ranged from 6 to 10 (median, 9).
CONCLUSION
The CAMIR technique combined with FHL tendon transfer is a good treatment for repair of Achilles tendon sleeve avulsion, with good recovery of ankle function and few complications.
Humans
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Achilles Tendon/diagnostic imaging*
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Middle Aged
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Male
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Female
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Tendon Transfer/methods*
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Minimally Invasive Surgical Procedures/methods*
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Adult
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Retrospective Studies
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Aged
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Treatment Outcome
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Tendon Injuries/surgery*
7.Effectiveness of Xuanshen Yishen Decoction on Intensive Blood Pressure Control: Emulation of a Randomized Target Trial Using Real-World Data.
Xiao-Jie WANG ; Yuan-Long HU ; Jia-Ming HUAN ; Shi-Bing LIANG ; Lai-Yun XIN ; Feng JIANG ; Zhen HUA ; Zhen-Yuan WANG ; Ling-Hui KONG ; Qi-Biao WU ; Yun-Lun LI
Chinese journal of integrative medicine 2025;31(8):677-684
OBJECTIVE:
To investigate the effectiveness of Xuanshen Yishen Decoction (XYD) in the treatment of hypertension.
METHODS:
Hospital electronic medical records from 2019-2023 were utilized to emulate a randomized pragmatic clinical trial. Hypertensive participants were eligible if they were aged ⩾40 years with baseline systolic blood pressure (BP) ⩾140 mm Hg. Patients treated with XYD plus antihypertensive regimen were assigned to the treatment group, whereas those who followed only antihypertensive regimen were assigned to the control group. The primary outcome assessed was the attainment rate of intensive BP control at discharge, with the secondary outcome focusing on the 6-month all-cause readmission rate.
RESULTS:
The study included 3,302 patients, comprising 2,943 individuals in the control group and 359 in the treatment group. Compared with the control group, a higher proportion in the treatment group achieved the target BP for intensive BP control [8.09% vs. 17.5%; odds ratio (OR)=2.29, 95% confidence interval (CI)=1.68 to 3.13; P<0.001], particularly in individuals with high homocysteine levels (OR=3.13; 95% CI=1.72 to 5.71; P<0.001; P for interaction=0.041). Furthermore, the 6-month all-cause readmission rate in the treatment group was lower than in the control group (hazard ratio=0.58; 95% CI=0.36 to 0.91; P=0.019), and the robustness of the results was confirmed by sensitivity analyse.
CONCLUSIONS
XYD could be a complementary therapy for intensive BP control. Our study offers real-world evidence and guides the choice of complementary and alternative therapies. (Registration No. ChiCTR2400086589).
Adult
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Aged
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Female
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Humans
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Male
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Middle Aged
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Antihypertensive Agents/pharmacology*
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Blood Pressure/drug effects*
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Drugs, Chinese Herbal/pharmacology*
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Hypertension/physiopathology*
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Patient Readmission
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Treatment Outcome
8.Effects of Poria cocos polysaccharides on improving mouse nonalcoholic fatty liver disease via regulation of Akt/mTOR/SREBP-1c signaling pathway
Shi-yao HUANG ; Liang KONG ; Jia-hua WANG ; Li-yan WANG ; Chao-wei SUN ; Xin-cheng LIU ; Yu-he DONG ; Li-yan GU
Chinese Traditional Patent Medicine 2025;47(1):58-65
AIM To investigate the improvement effects of Poria cocos polysaccharides(PCPs)on mouse nonalcoholic fatty liver disease(NAFLD).METHODS Forty-eight C57BL/6 mice were randomly divided into the blank group,the model group,the simvastatin group(4 mg/kg)and the high,medium and low dose PCPs groups(200,100 and 50 mg/kg),with 8 mice in each group.The NAFLD model was reproduced by 16 weeks feeding of high-fat and high-cholesterol diet,followed by 8 weeks administration of corresponding drug by gavage.The mice had their body mass and liver coefficient assessed;their levels of hepatic free fatty acid(FFA),and serum total cholesterol(TC),triglyceride(TG),high density lipoprotein cholesterol(HDL-C),low density lipoprotein cholesterol(LDL-C),aspartate aminotransferase(AST),alanine aminotransferase(ALT),γ-glutamyltransferase(γ-GT)and malondialdehyde(MDA)detected;their hepatic pathological changes and lipid deposition observed using HE staining,NAFLD activity score(NAS)and oil red O staining;and their hepatic protein expressions of Akt,mTOR,p-Akt,p-mTOR and SREBP-1c detected by Western blot.RESULTS Compared with the blank group,the model group demonstrated all increased body weight,liver coefficient,hepatic FFA level,and serum TC,TG,LDL-C,AST,ALT,γ-GT,MDA,IL-1β and TNF-α.levels(P<0.05,P<0.01);decreased HDL-C level and activities of SOD and GSH-Px(P<0.05,P<0.01);more obvious hepatic pathological damage as revealed by increased NAS score(P<0.01)and increased lipid deposition area(P<0.01).Compared with the model group,the groups intervened with high or medium dose PCPs,or simvastatin displayed decreased body weight,liver coefficient,hepatic FFA level,and serum TC,TG,LDL-C,AST,ALT,γ-GT,MDA,IL-1β and TNF-α levels(P<0.05,P<0.01);increased HDL-C level and SOD,GSH-Px activities(P<0.05,P<0.01);decreased hepatic pathological damage as revealed by the decreased NAS score and lipid deposition area(P<0.05,P<0.01);and decreased hepatic protein expressions of p-Akt,p-mTOR and SREBP-1c protein(P<0.05)as well.CONCLUSION PCPs can improve mouse NAFLD,and its mechanism may lie in their function in reversing abnormal lipid metabolism via Akt/mTOR/SREBP-1c signaling pathway.
9.Comparative efficacy of navigation system and orthopedic robot-assisted nail placement in the treatment of lower cervical fracture and dislocation
Xinnan CHENG ; Shuai LI ; Jiaojiao BAI ; Qingda LI ; Yukuan LEI ; Lei ZHU ; Zhen CHANG ; Zhigang ZHAO ; Yunfei HUANG ; Mingzhe FENG ; Liang YAN ; Hua HUI ; Lingbo KONG ; Baorong HE
Chinese Journal of Trauma 2025;41(2):148-156
Objective:To compare the clinical efficacy of navigation system and orthopedic robot-assisted nail placement in the treatment of lower cervical fracture and dislocation.Methods:A retrospective cohort study was conducted to analyze the clinical data of 49 patients with fracture and dislocation of the lower cervical spine who were admitted to Honghui Hospital, Xi′an Jiaotong University School of Medicine from May 2021 to October 2022, including 38 males and 11 females, aged 29-61 years [(39.3±7.3)years]. Injury segments involved C 3 in 12 patients, C 4 in 11, C 5 in 8, C 6 in 9 and C 7 in 9. Twenty-one patients were treated with S8 navigation system (navigation group, 84 screws), and 28 with TINAVI orthopedic robot (robot group, 112 screws). The two groups were compared in terms of the total surgical duration, single screw placement time, total screw placement time, distance between the screw and the anterior cortex, incision length, intraoperative radiation dose, intraoperative blood loss and length of hospital stay. The height of intervertebral space, Cobb angle, sliding distance between vertebral bodies and American Spinal Injury Association (ASIA) grade were assessed before surgery and at 3 days after surgery. Visual analogue scale (VAS), Japanese Orthopedic Association (JOA) score and neck dysfunction index (NDI) before surgery, at 3 days, 3 months after surgery and at the last follow-up were compared. The accuracy of screw placement, intraoperative invasion rate of adjacent facet joints and rate of postoperative complications (infection, screw loosening, etc.) were evaluated. Results:All the patients were followed up for 12-16 months [(13.6±1.9)months]. In the navigation group, the total surgical duration, distance from the screw to the anterior cortex and the intraoperative radiation dose were (236.2±30.6)minutes, (2.0±0.2)mm and (374.3±90.3)mGy respectively, which were significantly shorter or less than those in the robot group [(278.4±20.7)minutes, (10.6±2.9)mm and (448.4±77.9)mGy] ( P<0.01). The single screw placement time, total screw placement time, incision length and intraoperative blood loss were (3.5±0.4)minutes, (23.9±0.5)minutes, (9.1±2.4)cm and (422.2±30.4)ml respectively, which were significantly longer or more than those in the robot group [(2.6±0.2)minutes, (17.9±0.7)minutes, (6.6±2.6)cm and (360.3±56.3)ml] ( P<0.01). There was no significant difference in the length of hospital stay between the two groups ( P>0.05). No significant differences were observed in the height of the intervertebral space, Cobb angle, sliding distance between the vertebral bodies and ASIA grade between the two groups ( P>0.05). At 3 days after surgery, the height of intervertebral space, Cobb angle, sliding distance between vertebral bodies and ASIA grade in both groups were significantly improved when compared with those before surgery ( P<0.05 or 0.01). There were no significant differences in VAS, JOA scores or NDI between the two groups before surgery, at 3 days, 3 months after surgery and at the last follow-up ( P>0.05). The VAS, JOA scores and NDI in both groups were gradually improved at 3 days, 3 months and at the last follow-up after surgery when compared with those before surgery ( P<0.05). There was no significant difference in the accuracy of screw placement of levels 0 and 0+1 between the two groups ( P>0.05). No significant difference in the intraoperative invasion rate of adjacent facet joints between the two groups was found ( P>0.05). There were no serious complications such as infection or screw loosening after surgery in both groups. Conclusions:For lower cervical fracture and dislocation, although there are more advantages in total surgical duration, screw holding force and radiation control regarding the navigation system, and more outstanding performance in screw placement efficiency, incision length and intraoperative blood loss regarding the orthopedic robot, both of them can effectively rebuild the cervical structure, improve neurological function, relieve postoperative pain, improve screw placement accuracy and reduce facet joint injury and serious complications. Selection of the best auxiliary screw placement system should comprehensively consider patients′ conditions and the experience of the surgical team.
10.Antibacterial activity of the antifungal peptide Mt6 - 21DLeu derived from Musca domestica against Acinetobacter baumannii and the underlying mechanisms
Xuan HUA ; Tong QIU ; Xuyuan WANG ; Renxian TANG ; Delong KONG
Chinese Journal of Schistosomiasis Control 2025;37(5):482-493
Objective To investigate the antibacterial activity of the antifungal peptide Mt6-21DLeu derived from Musca domestica against Acinetobacter baumannii (AB) and unravel its underlying mechanisms, so as to provide insights into development of novel agents against AB. Methods The minimum inhibitory concentrations (MICs) of Mt6-21DLeu, M. domestica-derived antifungal peptide-1 (MAF-1A), and polymyxin B were determined against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and AB using the broth microdilution assay, and the antibacterial activity of Mt6-21DLeu and polymyxin B was dynamically assessed against AB over 24 hours with time-kill curves. The inhibitory effects of Mt6-21DLeu and polymyxin B on biofilm formation in AB at concentrations of 1/4 × MIC, 1/2 × MIC and MIC, and the eradication effects of Mt6-21DLeu and polymyxin B on mature biofilms in AB at concentrations of MIC, 2 × MIC, and 4 × MIC were evaluated using crystal violet staining. Structural changes in the cell membrane of AB were observed 3 hours post-exposure to Mt6-21DLeu at concentrations of MIC and 2 × MIC using scanning electron microscopy, and alterations in the cell membrane permeability of AB were analyzed 3 hours post-treatment with Mt6-21DLeu at concentrations of MIC and 2 × MIC by means of fluorescence microscopy and propidium iodide (PI) staining. Intracellular reactive oxygen species (ROS) levels in AB were measured 3 hours post-treatment with Mt6-21DLeu at concentrations of MIC, 2 × MIC, and 4 × MIC using flow cytometry. The survival of Caenorhabditis elegans exposed to Mt6-21DLeu at concentrations of MIC, 2 × MIC, and 4 × MIC was monitored for 7 consecutive days, and survival curves were plotted to evaluate the in vivo toxicity of Mt6-21DLeu. In addition, C. elegans infected with AB and treated with Mt6-21DLeu at a concentration of 4 × MIC served as the treatment group, and uninfected C. elegans served as the control group, while infected but untreated C. elegans served as the infection group. The in vivo antibacterial efficacy of Mt6-21DLeu at a concentration of 4 × MIC was evaluated by comparing the survival curves and bacterial load among the three groups. Results The MICs of MAF-1A were all >128 μg/mL against S. aureus, B. subtilis, E. coli, K. pneumoniae, P. aeruginosa, and AB. In contrast, the MICs of Mt6-21DLeu were >128, 32, 8, 8, 16, and 4 μg/mL against these strains, respectively, and the MIC of Mt6-21DLeu against AB was close to that of polymyxin B (2 μg/mL). Time-kill curve analysis showed that both Mt6-21DLeu at concentrations of MIC and 2 × MIC and polymyxin B at a concentration of MIC inhibited AB growth over the 24-hour study period. The biofilm biomass in AB was (52.38 ± 6.92)%, (40.88 ± 9.17)% and (14.77 ± 6.00)% post-exposure with Mt6-21DLeu at concentrations of 1/4 × MIC, 1/2 × MIC and MIC, (61.58 ± 7.35)%, (47.42 ± 5.51)% and (20.85 ± 10.48)% post-treatment with polymyxin B at concentrations of 1/4 × MIC, 1/2 × MIC and MIC, and (100.00 ± 15.92)% in the control group (only bacterial suspension), respectively (F = 68.38, P < 0.001), and pairwise comparisons indicated that Mt6-21DLeu and polymyxin B at all concentrations significantly inhibited biofilm formation as compared to the control group (all P values < 0.001). The mature biofilm biomass in AB was (73.44 ± 11.41)%, (72.56 ± 13.08)% and (49.65 ± 9.23)% post-exposure to Mt6-21DLeu at concentrations of MIC, 2 × MIC, and 4 × MIC, (84.38 ± 8.60)%, (72.31 ± 9.63)% and (58.85 ± 4.96)% post-treatment with polymyxin B at concentrations of MIC, 2 × MIC, and 4 × MIC, and (100.00 ± 6.36)% in the control group (F = 35.63, P < 0.001), and pairwise comparisons revealed that Mt6-21DLeu at all concentrations significantly eradicated biofilm biomass (all P values < 0.05); however, polymyxin B showed no clear-cut eradication effect at a concentration of MIC (P > 0.05). Scanning electron microscopy revealed pore formation and content leakage in the cell membrane of AB 3 hours post-treatment with Mt6-21DLeu at concentrations of MIC and 2 × MIC. Fluorescence microscopy showed that the proportions of PI-stained AB were (24.79 ± 11.51)% and (68.44 ± 15.80)% post-treatment with Mt6-21DLeu at concentrations of MIC and 2 × MIC, and (0.96 ± 0.94)% in the phosphate-buffered saline (PBS) treatment group (F = 105.90, P < 0.001), with the highest proportion of PI-stained AB seen post-treatment with Mt6-21DLeu at a concentration of 2 × MIC (P < 0.05). Flow cytometry revealed that the relative intracellular ROS levels in AB were (652.00 ± 141.90), (694.33 ± 14.19), and (974.33 ± 160.02) 3 hours post-treatment with Mt6-21DLeu at concentrations of MIC, 2 × MIC and 4 × MIC, and (403.67 ± 86.56) in the PBS treatment group, respectively (F = 12.27, P < 0.05), with the highest intracellular ROS level measured following treatment with Mt6-21DLeu at a concentration of 4 × MIC (P < 0.05). Survival curve analysis revealed that Mt6-21DLeu posed no impact on C. elegans survival at concentrations of MIC (χ2 = 0.02, P > 0.05), 2 × MIC (χ2 = 0.06, P > 0.05) or 4 × MIC (χ2 = 0.16, P > 0.05), and there was a significant difference in the survival period of C. elegans among the control group, the infection group, and the treatment group (χ2 = 82.66, P < 0.05), with a significantly longer survival period in the treatment group than in the infection group (χ2 = 45.00, P < 0.05). In addition, the log-transformed bacterial colony counts in C. elegans were (0.00 ± 0.00), (5.46 ± 0.03), and (3.91 ± 0.47) CFU/mL in the control group, the infection group, and the treatment group, respectively (F = 324.80, P < 0.001), and the log-transformed bacterial colony counts in C. elegans were significantly lower in the treatment group than in the infection group (P < 0.05). Conclusions Mt6-21DLeu exerts potent antibacterial effects through disrupting the cell membrane integrity of AB and promoting intracellular ROS accumulation in AB, and exhibits promising potential for treatment of AB infections both in vivo and in vitro, which may serve as a candidate drug molecule against multidrug-resistant AB infections.


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