2.Use of metallic ureteric stents for chronic ureteric obstruction and its association with value-based care.
Yu Xi Terence LAW ; Ang ZHOU ; David Terrence CONSIGLIERE ; Benjamin Yen Seow GOH ; Ho Yee TIONG
Singapore medical journal 2025;66(1):28-32
INTRODUCTION:
We aimed to compare the real-world data and our clinical experience with metallic stents (MSs) and conventional polymeric stents (PSs) in the management of both malignant and benign chronic ureteric obstruction (CUO), in terms of clinical outcomes and costs.
METHODS:
Clinical data from our institution, including outcomes for all ureteric stents inserted for long-term management of CUO from all causes from 2014 to 2017, were retrospectively reviewed and compared between the MS and PS episodes.
RESULTS:
A total of 247 stents were placed in 63 patients with CUO over the 4-year study period. Of these, 45 stents were MSs. There was no significant difference in all baseline characteristics between the MS and PS groups, except for the aetiology of obstructive cause. Mean indwelling stent duration was significantly greater for MS than for PS (228.6 ± 147.0 vs. 146.1 ± 66.0 days, P < 0.001), thereby leading to lower average number of stent changes per year in the MS group compared to the PS group (1.4 vs. 6.3 times, respectively). Despite the higher unit cost of MS compared to PS, there was no significant mean cost difference overall (cost per dwelling day SGD 7.82 ± SGD 10.44 vs. SGD 8.23 ± SGD 20.50, P = 0.888).
CONCLUSION
Resonance MS is a better option than PS to manage CUO from malignant and benign causes because its significantly longer indwelling time mitigates the higher unit cost of the stent. It potentially reduces the number of procedures and operations in patients. Thus, it should be considered for all patients with CUO requiring long-term ureteric drainage.
Humans
;
Ureteral Obstruction/economics*
;
Female
;
Male
;
Retrospective Studies
;
Stents/economics*
;
Middle Aged
;
Aged
;
Treatment Outcome
;
Chronic Disease
;
Ureter/surgery*
;
Metals
;
Adult
;
Aged, 80 and over
3.Preparation and application of conductive fiber coated with liquid metal.
Chengfeng LIU ; Jiabo TANG ; Ming LI ; Shihao ZHANG ; Yang ZOU ; Yonggang LYU
Journal of Biomedical Engineering 2025;42(4):724-732
Flexible conductive fibers have been widely applied in wearable flexible sensing. However, exposed wearable flexible sensors based on liquid metal (LM) are prone to abrasion and significant conductivity degradation. This study presented a high-sensitivity LM conductive fiber with integration of strain sensing, electrical heating, and thermochromic capabilities, which was fabricated by coating eutectic gallium-indium (EGaIn) onto spandex fibers modified with waterborne polyurethane (WPU), followed by thermal curing to form a protective polyurethane sheath. This fiber, designated as Spandex/WPU/EGaIn/Polyurethane (SWEP), exhibits a four-layer coaxial structure: spandex core, WPU modification layer, LM conductive layer, and polyurethane protective sheath. The SWEP fiber had a diameter of (458.3 ± 10.4) μm, linear density of (2.37 ± 0.15) g/m, and uniform EGaIn coating. The fiber had excellent conductivity with an average value of (3 716.9 ± 594.2) S/m. The strain sensing performance was particularly noteworthy. A 5 cm × 5 cm woven fabric was fabricated using polyester warp yarns and SWEP weft yarns. The fabric exhibited satisfactory moisture permeability [(536.06 ± 33.15) g/(m 2·h)] and maintained stable thermochromic performance after repeated heating cycles. This advanced conductive fiber development is expected to significantly promote LM applications in wearable electronics and smart textile systems.
Wearable Electronic Devices
;
Polyurethanes/chemistry*
;
Electric Conductivity
;
Gallium/chemistry*
;
Metals/chemistry*
4.Effects of elastic modulus of the metal block on the condylar-constrained knee prosthesis tibial fixation stability.
Yuhan ZHANG ; Jing ZHANG ; Tianqi DONG ; Xuan ZHANG ; Weijie ZHANG ; Lei GUO ; Zhenxian CHEN
Journal of Biomedical Engineering 2025;42(4):782-789
Although metal blocks have been widely used for reconstructing uncontained tibial bone defects, the influence of their elastic modulus on the stability of tibial prosthesis fixation remains unclear. Based on this, a finite element model incorporating constrained condylar knee (CCK) prosthesis, tibia, and metal block was established. Considering the influence of the post-restraint structure of the prosthesis, the effects of variations in the elastic modulus of the block on the von Mises stress distribution in the tibia and the block, as well as on the micromotion at the bone-prosthesis fixation interface, were investigated. Results demonstrated that collision between the insert post and femoral prosthesis during tibial internal rotation increased tibial von Mises stress, significantly influencing the prediction of block elastic modulus variation. A decrease in the elastic modulus of the metal block resulted in increased von Mises stress in the proximal tibia, significantly reduced von Mises stress in the distal tibia, decreased von Mises stress of the block, and increased micromotion at the bone-prosthesis fixation interface. When the elastic modulus of the metal block fell below that of bone cement, inadequate block support substantially increased the risk of stress shielding in the distal tibia and fixation interface loosening. Therefore, this study recommends that biomechanical investigations of CCK prostheses must consider the post-constraint effect, and the elastic modulus of metal blocks for bone reconstruction should not be lower than 3 600 MPa.
Knee Prosthesis
;
Humans
;
Finite Element Analysis
;
Tibia/surgery*
;
Elastic Modulus
;
Arthroplasty, Replacement, Knee/methods*
;
Stress, Mechanical
;
Metals
;
Prosthesis Design
;
Knee Joint/surgery*
;
Biomechanical Phenomena
5.Digital study of IdebergⅡregional pelvic fracture anatomical plate based on 3D metal printing technology.
Yi ZHANG ; Jia-Kai ZHANG ; Jun-Long WU ; Yi ZHENG
China Journal of Orthopaedics and Traumatology 2025;38(3):293-297
OBJECTIVE:
To establish digital model of Ideberg typeⅡregional glenoid fracture anatomical plate with 3D metal printing technology.
METHODS:
The scapular imaging data of a 34-year-old healthy male volunteer were retrospectively selected. Mimics 15.01, NX 12.0 and other software were used to design Ideberg typeⅡ regional scapular fracture guide plate system. STL data were input into a metal 3D printer to print 1∶1 scapular model and anatomical plate of scapular pelvis with guide sleeve. The fit of the plate was tested in vitro and the accuracy of the screw position was evaluated by imaging. The printing time of scapular model, design of the nail path and making time of the anatomic guided plate were recorded.
RESULTS:
3D metal-printed Ideberg typeⅡ guide plate for scapular fracture fitted well to 3D printed scapular model, the locking screw was oriented accurately, and X-ray and CT showed good screw position. The printing time of scapula model, time of nail path design and special-shaped anatomical guide plate production were 52.0, 15.0 and 320 min, respectively.
CONCLUSION
Anatomical plates based on 3D metal printing technology could achieve good adhesion of Ideberg typeⅡ regional fractures and precise screw placement, providing a new and accurate surgical method for the treatment of Ideberg typeⅡ glenoid fractures.
Humans
;
Printing, Three-Dimensional
;
Male
;
Adult
;
Bone Plates
;
Fractures, Bone/diagnostic imaging*
;
Fracture Fixation, Internal/methods*
;
Pelvic Bones/surgery*
;
Metals
;
Scapula/surgery*
;
Models, Anatomic
6.Relationship between blood heavy metals and female stress urinary incontinence from NHANES 2013-2018.
Environmental Health and Preventive Medicine 2025;30():45-45
BACKGROUND:
Research has demonstrated that heavy metals and cholesterol are associated with stress urinary incontinence (SUI) in women and that heavy metal exposure can cause dyslipidemia in humans. However, the potential mediating role of cholesterol in the relationship between heavy metals and female SUI remains unexplored.
METHODS:
The study utilized data from the National Health and Nutrition Examination Survey database from 2013-2018. Blood lead (Pb), cadmium (Cd), total mercury (Hg), manganese (Mn), selenium (Se), and methyl mercury (MeHg) were included in the study. The single and combined effects of the six metals exposure on SUI were examined using logistic analysis, restricted cubic spline (RCS) curves, weighted quantile sum (WQS) regression, and bayesian kernel machine regression (BKMR). The mediating effects of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were investigated through mediation analysis.
RESULTS:
The study included 2241 females, with 42.66% experiencing SUI. Initial analysis of six heavy metals revealed the associations between MeHg, Pb, Cd, total Hg, and SUI (all P < 0.05). WQS regression identified that Cd, Se, and Pb were major contributors to the mixed effect causing SUI. BKMR results indicated a positive mixed effect between six heavy metals and SUI. TC partially mediated the relationship of Pb, MeHg, and total Hg with SUI, and LDL-C partially mediated the association of Pb with SUI (all P for mediation < 0.05).
CONCLUSIONS
Blood heavy metal concentrations influence the development of female SUI, with blood cholesterol mediating the association between different heavy metals and SUI.
Humans
;
Female
;
Metals, Heavy/blood*
;
Nutrition Surveys
;
Middle Aged
;
Adult
;
United States/epidemiology*
;
Urinary Incontinence, Stress/chemically induced*
;
Environmental Pollutants/blood*
;
Aged
;
Cholesterol/blood*
;
Environmental Exposure
7.Acinetobacter sp. ME1: a multifunctional bacterium for phytoremediation utilizing melanin production, heavy metal tolerance, and plant growth promotion.
Journal of Zhejiang University. Science. B 2025;26(11):1103-1120
Microorganisms inhabiting soils contaminated with heavy metals produce melanin, a dark brown pigment, as a survival strategy. In this study, a melanin-producing bacterium, Acinetobacter sp. ME1, with heavy metal tolerance and plant growth-promoting traits, was isolated from abandoned mine soil. Strain ME1 exhibited growth at concentrations of Zn up to 250 mg/L, Cd and Pb up to 100 mg/L, and Cr up to 50 mg/L. It had the ability to produce the plant hormone indole-3-acetic acid and siderophores along with 1-aminocyclopropane-1-carboxylic acid deaminase and protease activities. Additionally, it showed antioxidant activity, including catalase and 2,2-diphenyl-1-picryhydrazyl (DPPH) scavenging activities. The optimal conditions for melanin production by ME1 were a pH of 7 and a temperature of 35 ℃. At 1000 mg/L, ME1-extracted melanin exhibited DPPH radical scavenging activity of (25.040±0.007)%, a sun protection factor of 15.200±0.260, and 19.6% antibacterial activity against the plant pathogen Xanthomonas campestris. Furthermore, its adsorption capacity was (0.235±0.073) mg/g melanin for Zn and (0.277±0.008) mg/g melanin for Ni. In plants of Brassica chinensis grown under conditions of hydroponic cultivation with single heavy metal contamination of Cd, Zn, Pb, or Cr, the removal efficiency of each heavy metal was improved by 0.1‒1.8 times after 3 d following inoculation with the strain ME1 compared to the plants grown under the same conditions without inoculation. In addition, ME1 inoculation improved the removal efficiency of each heavy metal by 0.1‒1.0 times under multiple heavy metal contamination conditions. These findings suggest that Acinetobacter sp. ME1 could be used to enhance phytoremediation efficiency in heavy metal-contaminated soils. Moreover, the melanin it produces also holds promise in cosmetics, household products, and medical applications due to its photoprotective, antioxidant, and antimicrobial properties.
Acinetobacter/metabolism*
;
Biodegradation, Environmental
;
Metals, Heavy/metabolism*
;
Melanins/metabolism*
;
Soil Microbiology
;
Antioxidants/metabolism*
;
Plant Development
;
Soil Pollutants/metabolism*
;
Indoleacetic Acids/metabolism*
8.Latest research progress of rare earth-magnesium alloys in orthopedics.
Zhengming SUN ; Kun ZUO ; Xinke ZHU ; Hao YUE ; Zhengchao GAO
Journal of Southern Medical University 2025;45(2):437-442
Due to their good properties of elastic modulus, degradability and ability to promote bone repair, magnesium alloys have become a research hotspot in research of orthopedic implants. Nevertheless, most of the biomedical magnesium alloys currently available fail to meet the requirements in orthopedics because of their rapid degradation after implantation. Rare earth-magnesium alloys possess excellent corrosion resistance and are expected to become important materials as clinical orthopedic implants. This review summarizes the recent progress in studies of the physiological functions of rare earth elements, the effects of supplementation of rare earth elements on biomechanical properties and the in vitro and in vivo biocompatibility of magnesium alloys, and their contribution to tendon-bone healing, addressing also the current clinical orthopedic applications of different rare earth-magnesium alloys, challenges, and future strategies for improving these alloys.
Alloys/chemistry*
;
Magnesium/chemistry*
;
Metals, Rare Earth/chemistry*
;
Humans
;
Biocompatible Materials
;
Prostheses and Implants
9.Association of Co-Exposure to Polycyclic Aromatic Hydrocarbons and Metal(loid)s with the Risk of Neural Tube Defects: A Case-Control Study in Northern China.
Xiao Qian JIA ; Yuan LI ; Lei JIN ; Lai Lai YAN ; Ya Li ZHANG ; Ju Fen LIU ; Le ZHANG ; Linlin WANG ; Ai Guo REN ; Zhi Wen LI
Biomedical and Environmental Sciences 2025;38(2):154-166
OBJECTIVE:
Exposure to polycyclic aromatic hydrocarbons (PAHs) or metal(loid)s individually has been associated with neural tube defects (NTDs). However, the impacts of PAH and metal(loid) co-exposure and potential interaction effects on NTD risk remain unclear. We conducted a case-control study in China among population with a high prevalence of NTDs to investigate the combined effects of PAH and metal(loid) exposures on the risk of NTD.
METHODS:
Cases included 80 women who gave birth to offspring with NTDs, whereas controls were 50 women who delivered infants with no congenital malformations. We analyzed the levels of placental PAHs using gas chromatography and mass spectrometry, PAH-DNA adducts with 32P-post-labeling method, and metal(loid)s with an inductively coupled plasma mass spectrometer. Unconditional logistic regression was employed to estimate the associations between individual exposures and NTDs. Least absolute shrinkage and selection operator (LASSO) penalized regression models were used to select a subset of exposures, while additive interaction models were used to identify interaction effects.
RESULTS:
In the single-exposure models, we found that eight PAHs, PAH-DNA adducts, and 28 metal(loid)s were associated with NTDs. Pyrene, selenium, molybdenum, cadmium, uranium, and rubidium were selected through LASSO regression and were statistically associated with NTDs in the multiple-exposure models. Women with high levels of pyrene and molybdenum or pyrene and selenium exhibited significantly increased risk of having offspring with NTDs, indicating that these combinations may have synergistic effects on the risk of NTDs.
CONCLUSION
Our findings suggest that individual PAHs and metal(loid)s, as well as their interactions, may be associated with the risk of NTDs, which warrants further investigation.
Humans
;
Neural Tube Defects/chemically induced*
;
Polycyclic Aromatic Hydrocarbons/adverse effects*
;
Female
;
Case-Control Studies
;
China/epidemiology*
;
Adult
;
Pregnancy
;
Environmental Pollutants
;
Maternal Exposure/adverse effects*
;
Metals/toxicity*
;
Young Adult
;
Risk Factors
10.Research progress on metal pollutants inducing neurotoxicity through ferroptosis.
Ziyu QIN ; Yuqing CHEN ; Xinyuan ZHAO ; Shali YU
Journal of Zhejiang University. Medical sciences 2024;53(6):699-707
It has been confirmed that exposure to various metal pollutants can induce neurotoxicity, which is closely associated with the occurrence and development of neurological disorders. Ferroptosis is a form of cell death in response to metal pollutant exposure and it is closely related to oxidative stress, iron metabolism and lipid peroxidation. Recent studies have revealed that ferroptosis plays a significant role in the neurotoxicity induced by metals such as lead, cadmium, manganese, nickel, and antimony. Lead exposure triggers ferroptosis through oxidative stress, iron metabolism disorder and inflammation. Cadmium can induce ferroptosis through iron metabolism, oxidative stress and ferroptosis related signaling pathways. Manganese can promote ferroptosis through mitochondrial dysfunction, iron metabolism disorder and oxidative stress. Nickel can promote ferroptosis by influencing mitochondrial function, disrupting iron homeostasis and facilitating lipid peroxidation in the central nervous system. Antimony exposure can induce glutathione depletion by activating iron autophagy, resulting in excessive intracellular iron deposition and ultimately causing ferroptosis. This article reviews the effects of metal pollutants on ferroptosis-related indicators and discusses the specific mechanisms by which each metal triggers ferroptosis. It provides a reference for identifying targets for preventing neurotoxicity and for developing treatment strategies for neurological disorders.
Ferroptosis/drug effects*
;
Humans
;
Iron/metabolism*
;
Oxidative Stress/drug effects*
;
Neurotoxicity Syndromes/metabolism*
;
Cadmium/adverse effects*
;
Animals
;
Lipid Peroxidation/drug effects*
;
Metals/metabolism*
;
Lead/adverse effects*
;
Environmental Pollutants/toxicity*
;
Manganese/adverse effects*
;
Nickel/adverse effects*
;
Mitochondria/drug effects*
;
Signal Transduction/drug effects*


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