Lymph nodes are innervated by a unique population of sensory neurons with immunomodulatory potential.

Barrier tissue immune responses are regulated in part by nociceptors. Nociceptor ablation alters local immune responses at peripheral sites and within draining lymph nodes (LNs). The mechanisms and significance of nociceptor-dependent modulation of LN function are unknown. Using high-resolution imaging, viral tracing, single-cell transcriptomics, and optogenetics, we identified and functionally tested a sensory neuro-immune circuit that is responsive to lymph-borne inflammatory signals. Transcriptomics profiling revealed that multiple sensory neuron subsets, predominantly peptidergic nociceptors, innervate LNs, distinct from those innervating surrounding skin. To uncover LN-resident cells that may interact with LN-innervating sensory neurons, we generated a LN single-cell transcriptomics atlas and nominated nociceptor target populations and interaction modalities. Optogenetic stimulation of LN-innervating sensory fibers triggered rapid transcriptional changes in the predicted interacting cell types, particularly endothelium, stromal cells, and innate leukocytes. Thus, a unique population of sensory neurons monitors peripheral LNs and may locally regulate gene expression.

Nociceptor neurons affect cancer immunosurveillance.

Solid tumours are innervated by nerve fibres that arise from the autonomic and sensory peripheral nervous systems1-5. Whether the neo-innervation of tumours by pain-initiating sensory neurons affects cancer immunosurveillance remains unclear. Here we show that melanoma cells interact with nociceptor neurons, leading to increases in their neurite outgrowth, responsiveness to noxious ligands and neuropeptide release. Calcitonin gene-related peptide (CGRP)-one such nociceptor-produced neuropeptide-directly increases the exhaustion of cytotoxic CD8+ T cells, which limits their capacity to eliminate melanoma. Genetic ablation of the TRPV1 lineage, local pharmacological silencing of nociceptors and antagonism of the CGRP receptor RAMP1 all reduced the exhaustion of tumour-infiltrating leukocytes and decreased the growth of tumours, nearly tripling the survival rate of mice that were inoculated with B16F10 melanoma cells. Conversely, CD8+ T cell exhaustion was rescued in sensory-neuron-depleted mice that were treated with local recombinant CGRP. As compared with wild-type CD8+ T cells, Ramp1-/- CD8+ T cells were protected against exhaustion when co-transplanted into tumour-bearing Rag1-deficient mice. Single-cell RNA sequencing of biopsies from patients with melanoma revealed that intratumoral RAMP1-expressing CD8+ T cells were more exhausted than their RAMP1-negative counterparts, whereas overexpression of RAMP1 correlated with a poorer clinical prognosis. Overall, our results suggest that reducing the release of CGRP from tumour-innervating nociceptors could be a strategy to improve anti-tumour immunity by eliminating the immunomodulatory effects of CGRP on cytotoxic CD8+ T cells.

Clinical efficacy of sodium aescinate administration following endovenous laser ablation for varicose veins.

BACKGROUND: Endovenous interventions and minimally invasive procedures are effective in the management of varicose veins. However, they can cause postoperative discomfort. OBJECTIVE: To evaluate the clinical efficacy of sodium aescinate (SA) in improving edema, pain, vein-specific symptoms, and quality of life in patients following endovenous laser ablation (EVLA) for varicose veins. METHODS: In this single-center randomized controlled trial (RCT), patients were allocated into two groups: in Group A, 60 mg SA was administered twice daily for 20 days, and in Group B (control), no venoactive drug was prescribed. The Clinical-Etiology-Anatomy-Pathophysiology (CEAP) classification system for chronic venous disorders was used to assess the varicose veins. The circumferences of the calf and ankle were recorded for evaluating edema. The 10-point Visual Analog Scale (VAS), Venous Clinical Severity Score (VCSS), and Aberdeen Varicose Veins Questionnaire (AVVQ) were used to measure the pain intensity, overall varicose vein severity, and patient's quality of life, respectively. RESULTS: The study included 87 patients (mean age, 59.9 ± 10.7 years; 54 men) with CEAP class C2-C5 varicose veins who underwent EVLA and phlebectomy or foam sclerotherapy. The calf circumference recovered quicker in Group A than in Group B by days 10, 21, and 30 (difference from baseline was 1.04 ± 0.35 vs 2.39 ± 1.15 [p < .001], 0.48 ± 0.42 vs1.73 ± 1.00 [p < .001], and 0.18 ± 0.64 vs 0.82 ± 0.96 [p < .001], respectively). The ankle circumference recovered quicker in Group A than in Group B by days 10 and 21 (the difference from baseline was 1.37 ± 0.52 vs 2.36 ± 0.93 [p < .001] and 0.58 ± 0.60 vs 1.14 ± 0.88 [p = .002], respectively). Pain relief was achieved quicker in Group A than in Group B (0.257 ± 1.097 [p = .0863] vs 0.506 ± 1.250 [p = .0168] by day 21). There were no significant differences in the VCSS and AVVQ scores between both groups. There were no drug-related adverse effects. CONCLUSIONS: SA, in combination with compression therapy, can relieve edema and alleviate pain in patients following EVLA for varicose veins.

Two common nanoparticles exert immunostimulatory and protective effects in Tegillarca granosa against Vibrio parahaemolyticus.

There are many studies revealed that metal-based nanoparticles (NPs) possess excellent bactericidal effect on multitudinous bacteria and fungi. However, the control effect of NPs as antimicrobial agents to against Vibrio parahaemolyticus infection remain in poorly understood for blood clam, Tegillarca granosa. In order to evaluate the effect, the changes in six physiological parameters and the immune-related genes expression of clams exposed to V. parahaemolyticus alone or along with NPs (nZnO or nCuO) were investigated in present study. Results showed that both tested NPs exerted prominent redemptive or mitigative effect in an inverse dose-dependent way on physiological indexes of clam, especially in the total counts, phagocytosis and the cell viability of haemocytes, as well as the concentration and activity of lysozymes, when co-exposed with Vibrio. Gene expression analysis showed NPs at a concentration of 0.1 mg/L generally mitigated the downregulation of immune-related genes after clam exposure to V. parahaemolyticus. The combination of 0.1 mg/mL nZnO and nCuO additives has been shown to significantly enhance the humoral immunity of blood clam, suggesting its potential as a protective measure against V. parahaemolyticus infection in T. granosa.

In Vitro Efficacy of Terpenes from Essential Oils against Sarcoptes scabiei.

The mite Sarcoptes scabiei is responsible for the emerging or re-emerging skin disease called scabies in humans and sarcoptic mange in animals. Essential oils represent an appealing alternative strategy for the control of Sarcoptes infections, but the commercial development of essential oils may be hampered by their inconsistency in efficacy due to their varied chemical compositions. In order to address this issue, we assessed the efficacy of six components (carvacrol, eugenol, geraniol, citral, terpinen-4-ol, and linalool) against S. scabiei. At a concentration of 0.5%, carvacrol presented the best miticidal efficacy, with a median lethal time (LT50) value of 6.7 min, followed by eugenol (56.3 min), geraniol (1.8 h), citral (6.1 h), terpinen-4-ol (22.3 h), and linalool (39.9 h). The LC50 values at 30 min for carvacrol, eugenol, and geraniol were 0.24, 0.79, and 0.91%, respectively. In conclusion, carvacrol, eugenol, and geraniol represent potential complementary or alternative agents for S. scabiei infections in humans or animals. Our study provides a scientific basis for the development of scabicidal products based on essential oils.

Compact Biomimetic Hair Sensors Based on Single Silicon Nanowires for Ultrafast and Highly-Sensitive Airflow Detection.

Wearable sensors that can mimic functionalities of human bodies have attracted intense recent attention. However, research on wearable airflow sensors is still lagging behind. Herein, we report a biomimetic hair sensor based on a single ultralong silicon nanowire (SiNW-BHS) for airflow detection. In our device, the SiNW can provide both mechanical and electrical responses in airflow, which enables a simple and compact design. The SiNW-BHSs can detect airflow with a low detection limit (<0.15 m/s) and a record-high response speed (response time <40 ms). The compact design of the SiNW-BHSs also enables easy integration of an array of devices onto a flexible substrate to mimic human skin to provide comprehensive airflow information including wind speed, incident position, incident angle, and so forth. This work provides novel-designed BHSs for ultrafast and highly sensitive airflow detection, showing great potential for applications such as e-skins, wearable electronics, and robotics.

Procyanidin B1 promotes in vitro maturation of pig oocytes by reducing oxidative stress.

Oxidative stress negatively affects the in vitro maturation (IVM) of oocytes. Procyanidin B1 (PB1) is a natural polyphenolic compound that has antioxidant properties. In this study, we investigated the effect of PB1 supplementation during IVM of porcine oocytes. Treatment with 100 µM PB1 significantly increased the MII oocytes rate (p <0.05), the parthenogenetic (PA) blastocyst rate (p <0.01) and the total cell number in the PA blastocyst (p < 0.01) which were cultured in regular in vitro culture (IVC) medium. The PA blastocyst rate of regular MII oocytes activated and cultured in IVC medium supplemented with 100 and 150 µM PB1 significantly increased compared with control (p < 0.01 and p < 0.05). We also evaluated the reactive oxygen species (ROS) levels, mitochondrial membrane potential (Δψm) levels, glutathione (GSH) levels, and apoptotic levels in MII oocytes and cumulus cells following 100 µM PB1 treatment. The results showed that the PB1 supplementation decreased ROS production and apoptotic levels. In addition, PB1 was found to increase Δψm levels and GSH levels. In conclusion, PB1 inhibited apoptosis of oocytes and cumulus cells by reducing oxidative stress. Moreover, PB1 improved the quality of oocytes and promoted PA embryo development. Taken together, our results suggest that PB1 is a promising antioxidant additive for IVM of oocytes.

The association between living environmental factors and adolescents' body weight: a cross-sectional study.

BACKGROUND: The effect of the living environment on public health has received increasingly scholarly attention. This study aims to explore the relationship between adolescents' body weight and their living environmental factors. METHODS: This cross-sectional study comprised 1362 middle-school students from Nanjing and 826 from Changzhou in China. We further collected information on living environmental factors based on their home address and ran multivariate logistic regressions to explore potential correlations after considering a range of potential confounding factors. RESULTS: Approximately 25% (n = 303) of students from Nanjing and 26% (n = 205) of students from Changzhou were excessive body weight. In Nanjing, students' BMI (Body Mass Index) showed a strong negative correlation with the number of sports venues in their neighborhood (Adjusted Odds Ratio (AOR): 0.64, 95%CI: 0.40-0.94) after controlling for other covariates. In Changzhou, we observed a positive correlation between adolescents' body weight and the number of bus stops in their neighbourhood (AOR:1.63, 95%CI:1.11-2.38). CONCLUSIONS: The living environment factors were independently associated with teenagers' excessive body weight. We hypothesis that the environmental risk factors might be associated with political management, which will consequently affect personal health outcomes. Further research and proactive measures are required to manage those potential risks and attenuate the problem.

Ultraminiaturized Stretchable Strain Sensors Based on Single Silicon Nanowires for Imperceptible Electronic Skins.

Miniaturized stretchable strain sensors are key components in E-skins for applications such as personalized health-monitoring, body motion perception, and human-machine interfaces. However, it remains a big challenge to fabricate miniaturized stretchable strain sensors with high imperceptibility. Here, we reported for the first time novel ultraminiaturized stretchable strain sensors based on single centimeter-long silicon nanowires (cm-SiNWs). With the diameter of the active materials even smaller than that of spider silks, these sensors are highly imperceptible. They exhibit a large strain sensing range (>45%) and a high durability (>10 000 cycles). Their optimum strain sensing ranges could be modulated by controlling the prestrains of the stretchable cm-SiNWs. On the basis of this capability, sensors with appropriate sensing ranges were chosen to respectively monitor large and subtle human motions including joint motion, swallow, and touch. The strategy of applying single cm-SiNWs in stretchable sensors would open new doors to fabricate ultraminiaturized stretchable devices.

Suppression of substrate mode in GaN-based green laser diodes.

Parasitic substrate mode readily appears in GaN-based laser diodes (LDs) because of insufficient optical confinement, especially for green LDs. Substrate modes affect the behavior of a LD severely, including the laser beam quality, the optical output power, the longitudinal mode stability, and the maximum modulation speed. In this article, systematic studies on the n-cladding layer (CL) design to suppress the substrate mode of GaN-based green LDs were carried out. We established a contour map to describe the relationship between the optical confinement (determined by the thickness and the refractive index) of n-CL and the substrate mode intensity by simulating the near-field pattern and the far-field pattern. We found that it was difficult to obtain the Gaussian-shape far-field pattern using AlGaN as a cladding layer due to the appearance of cracks induced by tensile strain. However, this can be realized by introducing quaternary AlInGaN as a cladding layer since refractive index and strain can be tuned separately for quaternary alloy.

LncWNT3-IT affects the proliferation of Sertoli cells by regulating the expression of the WNT3 gene in goat testis.

The proliferation and differentiation ability of testicular Sertoli cells directly affects spermatogenesis and male reproductive development. WNT proteins are involved in the regulation of cell proliferation, differentiation and spermatogenesis. Therefore, to study whether lncRNAs, which regulate the expression of WNT proteins during cell proliferation and differentiation, are worthwhile. In this study, testicular tissue from the Dazu black goat (Capra, goat, Chongqing, China) at neonatal time (less than 7 days old), early puberty time (45 days old) and sexual maturity time (90 days old) at three ages was subjected to high-throughput sequencing to predict testicular growth and development associated with WNT lncRNA. The final screening of lncWNT3-IT may be targeted to regulate the expression of WNT3. At the same time, the expression of WNT3 was verified by lncWNT3-IT by paraffin sectioning, fluorescence in situ hybridization, interference, overexpression, cytotoxicity assay, Western blotting and qPCR. The following results were obtained: lncWNT3-IT was expressed in the testicular Sertoli cells and played a role in the Sertoli cell cytoplasm. Fluorescence in situ hybridization localization analysis showed that lncWNT3-IT positively regulated the expression of WNT3, and through cell viability and cell proliferation experiments, it was found that the expression of lncWNT3-IT assisted in Sertoli cell proliferation. In summary, lncWNT3-IT can influence the proliferation of Sertoli cells by positively regulating the expression of WNT3.

The Regulation of Immunological Processes by Peripheral Neurons in Homeostasis and Disease.

The nervous system and the immune system are the principal sensory interfaces between the internal and external environment. They are responsible for recognizing, integrating, and responding to varied stimuli, and have the capacity to form memories of these encounters leading to learned or 'adaptive' future responses. We review current understanding of the cross-regulation between these systems. The autonomic and somatosensory nervous systems regulate both the development and deployment of immune cells, with broad functions that impact on hematopoiesis as well as on priming, migration, and cytokine production. In turn, specific immune cell subsets contribute to homeostatic neural circuits such as those controlling metabolism, hypertension, and the inflammatory reflex. We examine the contribution of the somatosensory system to autoimmune, autoinflammatory, allergic, and infectious processes in barrier tissues and, in this context, discuss opportunities for therapeutic manipulation of neuro-immune interactions.

Correlation between MCP-1-2518A/G polymorphism and the risk of Alzheimer's disease.

The -2518A/G polymorphism in monocyte chemotactic protein-1 (MCP-1) has been extensively investigated for association with Alzheimer's disease (AD); however, the results from different studies are inconsistent. The aim of this study was to draw an accurate conclusion of the association. All eligible case-control studies were searched in PubMed, Embase, Chinese National Knowledge Infrastructure, China Biological Medicine Databases, and Wanfang Databases. Eight case-control studies with a total of 2370 cases and 2413 controls were eligible to be included in this meta-analysis. The association was evaluated by calculating the odds ratios (ORs) with the corresponding 95% confidence intervals (CIs). Overall, there was no significant association between MCP-1-2518A/G polymorphism and AD risk in all genetic models (the allele model G vs. A: OR = 1.15, 95% CI 0.92-1.45, p = 0.22; the co-dominant model GG vs. AA: OR = 1.38, 95% CI 0.80-2.36, p = 0.25; the dominant model AG + GG vs. AA: OR = 1.14, 95% CI 0.89-1.46, p = 0.31; the recessive model GG vs. AG + AA: OR = 1.35, 95% CI 0.87-2.09, p = 0.18). In subgroup analysis by ethnicity, a significant difference was not detected in both Caucasians and Asians. In allele model (G vs. A), the required sample size of 31858 was calculated by applying trial sequential analysis. Cumulative z curve is always below the trial sequential monitoring boundary and is nominally statistically significant (Z = 1.96). A consistent result was obtained in other genetic models. In summary, the present meta-analysis suggests that MCP-1-2518A/G polymorphism may not be associated with genetic susceptibility of AD in general population, but the association remains indeterminate due to the insufficient evidence.

Association of CD14-260 (-159) C/T and Alzheimer's disease: systematic review and trial sequential analyses.

Current studies have evaluated the association between CD14-260 (also known as -159) C/T polymorphism and Alzheimer's disease (AD) susceptibility. However, the association remains inconclusive. The aim of this study was to draw an accurate conclusion of the association. The literature search was conducted using PubMed, Embase, Chinese National Knowledge Infrastructure, China Biological Medicine Database, and Wanfang Databases for related articles. Four case-control studies with a total of 868 cases and 766 controls were eligible to be included in this meta-analysis. The association was evaluated by calculating the odds ratios (ORs) with the corresponding 95% confidence intervals (CIs). Overall, there was no significant association between CD14-260C/T polymorphism and AD risk in all genetic models (the allele model T vs. C: OR = 1.06, 95% CI 0.92-1.21, p = 0.44; the homozygous model TT vs. CC: OR = 1.09, 95% CI 0.83-1.44, p = 0.53; the heterozygote model CT vs. CC: OR = 0.95, 95% CI 0.75-1.22, p = 0.71; the dominant model TT + CT vs. CC: OR = 1.05, 95% CI 0.84-1.32, p = 0.66; the recessive model TT vs. CT + CC: OR = 1.14, 95% CI 0.92-1.43, p = 0.24). The sample size of 5064 was calculated by applying trial sequential analysis. Cumulative z curve does not cross trial sequential monitoring boundary. In conclusion, the present meta-analysis suggests that the CD14-260C/T polymorphism may not be associated with genetic susceptibility of AD, but the association remains indeterminate due to the insufficient evidence.

Coronary veins determine the pattern of sympathetic innervation in the developing heart.

Anatomical congruence of peripheral nerves and blood vessels is well recognized in a variety of tissues. Their physical proximity and similar branching patterns suggest that the development of these networks might be a coordinated process. Here we show that large diameter coronary veins serve as an intermediate template for distal sympathetic axon extension in the subepicardial layer of the dorsal ventricular wall of the developing mouse heart. Vascular smooth muscle cells (VSMCs) associate with large diameter veins during angiogenesis. In vivo and in vitro experiments demonstrate that these cells mediate extension of sympathetic axons via nerve growth factor (NGF). This association enables topological targeting of axons to final targets such as large diameter coronary arteries in the deeper myocardial layer. As axons extend along veins, arterial VSMCs begin to secrete NGF, which allows axons to reach target cells. We propose a sequential mechanism in which initial axon extension in the subepicardium is governed by transient NGF expression by VSMCs as they are recruited to coronary veins; subsequently, VSMCs in the myocardium begin to express NGF as they are recruited by remodeling arteries, attracting axons toward their final targets. The proposed mechanism underlies a distinct, stereotypical pattern of autonomic innervation that is adapted to the complex tissue structure and physiology of the heart.

Advanced deep learning models for phenotypic trait extraction and cultivar classification in lychee using photon-counting micro-CT imaging.

Introduction: In contemporary agronomic research, the focus has increasingly shifted towards non-destructive imaging and precise phenotypic characterization. A photon-counting micro-CT system has been developed, which is capable of imaging lychee fruit at the micrometer level and capturing a full energy spectrum, thanks to its advanced photon-counting detectors. Methods: For automatic measurement of phenotypic traits, seven CNN-based deep learning models including AttentionUNet, DeeplabV3+, SegNet, TransUNet, UNet, UNet++, and UNet3+ were developed. Machine learning techniques tailored for small-sample training were employed to identify key characteristics of various lychee species. Results: These models demonstrate outstanding performance with Dice, Recall, and Precision indices predominantly ranging between 0.90 and 0.99. The Mean Intersection over Union (MIoU) consistently falls between 0.88 and 0.98. This approach served both as a feature selection process and a means of classification, significantly enhancing the study's ability to discern and categorize distinct lychee varieties. Discussion: This research not only contributes to the advancement of non-destructive plant analysis but also opens new avenues for exploring the intricate phenotypic variations within plant species.

C/EBPα aggravates renal fibrosis in CKD through the NOX4-ROS-apoptosis pathway in tubular epithelial cells.

BACKGROUND: Chronic kidney disease (CKD) is a prevalent renal disorder with various risk factors. Emerging evidence indicates that the transcriptional factor CCAAT/enhancer binding protein alpha (C/EBPα) may be associated with renal fibrosis. However, the precise role of C/EBPα in CKD progression remains unexplored. METHODS: We investigated the involvement of C/EBPα in CKD using two distinct mouse models induced by folic acid (FA) and unilateral ureteral obstruction (UUO). Additionally, we used RNA sequencing and KEGG analysis to identify potential downstream pathways governed by C/EBPα. FINDINGS: Cebpa knockout significantly shielded mice from renal fibrosis and reduced reactive oxygen species (ROS) levels in both the FA and UUO models. Primary tubular epithelial cells (PTECs) lacking Cebpa exhibited reduced apoptosis and ROS accumulation following treatment with TGF-ß. RNA sequencing analysis suggested that apoptosis is among the primary pathways regulated by C/EBPα, and identified NADPH oxidoreductase 4 (NOX4) as a key protein upregulated upon C/EBPα induction (ICCB280). Treatment with l-Theanine, a potential NOX4 inhibitor, mitigated renal fibrosis and inflammation in both the FA and UUO mouse models. INTERPRETATION: Our study unveils a role for C/EBPα in suppressing renal fibrosis, mitigating ROS accumulation, and reducing cell apoptosis. Furthermore, we investigate whether these protective effects are mediated by C/EBPα's regulation of NOX4 expression. These findings present a promising therapeutic target for modulating ROS and apoptosis in renal tubular cells, potentially offering an approach to treating CKD and other fibrotic diseases.

Association Between Adherence to 24-Hour Movement Guidelines and Noncommunicable Disease Risk in Chinese Adults: Prospective Cohort Study.

BACKGROUND: The increasing annual global deaths are attributable to noncommunicable chronic diseases (NCDs). Adhering to healthy lifestyle behaviors is associated with lower NCD risk, particularly among individuals with ample movement, enough sleep, and reduced sedentariness. Nevertheless, there are only few prospective assessments on the association of interactions between daily activities with NCD prevention, while the associations between adhering to Canadian 24-Hour Movement Guidelines (24HGs) for adults and NCD risks are still unknown. Compared to the general population, obese and overweight populations are at a higher risk of developing NCDs. Currently, it is unclear whether the health benefits of adhering to 24HGs differ between the general population and the obese population. OBJECTIVE: This study explores prospective associations between adherence to 24HGs and NCD risks by weight status among overweight and obese adults in China. METHODS: This decadal study consists of 9227 adults aged 35 years and older without any major NCDs at enrolment in the China Health and Nutrition Survey (2004-2011) and followed up until 2015. The exposure of interest was the overall score of compliance with 24HGs measured by participants' self-report, wherein 1 point was assigned for compliance to each component, resulting in an aggregated score ranging from 0 to 3. The primary outcome was the first occurrence of major NCDs (high blood pressure, stroke, diabetes, cancer, and acute myocardial infarction). Log-binomial regression models were used to evaluate the associations. RESULTS: : Overall, 4315 males and 4912 females, with 25,175 person-years of follow-up, were included in our analyses. The average baseline age was 50.21 (SD 11.04) years. Among the overweight and obese groups, those adhering to 1 (risk ratio [RR] 0.37, 95% CI 0.19-0.74; P=.004), 2 (RR 0.37, 95% CI 0.19-0.72; P=.003), and 3 (RR 0.32, 95% CI 0.14-0.73; P=.006) recommendations of 24HGs had a significantly lower NCD risk than those not adhering to any of the activity guidelines. Among the normal or underweight groups, those adhering to 1 (RR 0.49, 95% CI 0.27-0.96; P=.03) and 3 (RR 0.40, 95% CI 0.17-0.94; P=.03) components had a significantly lower NCD risk than those not adhering to any of the activity guidelines. CONCLUSIONS: In this prospective study, we found that active adherence to recommendations of 24HGs was associated with lower risks of NCDs, especially among overweight and obese participants. Additionally, overweight and obese individuals who met at least 1 component of 24HGs were at a significantly lower risk for NCDs, but this protective effect was not found among individuals in the normal and underweight groups. Individuals with excess body weight who tend to be more susceptible to health risks may gain greater health benefits than the general population by adhering to the recommendations of 24HGs.

Fluoroscopically calibrated 3D-printed patient-specific instruments improve the accuracy of osteotomy during bone tumor resection adjacent to joints.

BACKGROUND: Inadequate surface matching, variation in the guide design, and soft tissue on the skeletal surface may make it difficult to accurately place the 3D-printed patient-specific instrument (PSI) exactly to the designated site, leading to decreased accuracy, or even errors. Consequently, we developed a novel 3D-printed PSI with fluoroscopy-guided positioning markers to enhance the accuracy of osteotomies in joint-preserving surgery. The current study was to compare whether the fluoroscopically calibrated PSI (FCPSI) can achieve better accuracy compared with freehand resection and conventional PSI (CPSI) resection. METHODS: Simulated joint-preserving surgery was conducted using nine synthetic left knee bone models. Osteotomies adjacent to the knee joint were designed to evaluate the accuracy at the epiphysis side. The experiment was divided into three groups: free-hand, conventional PSI (CPSI), and fluoroscopically Calibrated PSI (FCPSI). Post-resection CT scans were quantitatively analyzed. Analysis of variance (ANOVA) was used. RESULT: FCPSI improved the resection accuracy significantly. The mean location accuracy is 2.66 mm for FCPSI compared to 6.36 mm (P < 0.001) for freehand resection and 4.58 mm (P = 0.012) for CPSI. The mean average distance is 1.27 mm compared to 2.99 mm (p < 0.001) and 2.11 mm (p = 0.049). The mean absolute angle is 2.16° compared to 8.50° (p < 0.001) and 5.54° (p = 0.021). The mean depth angle is 1.41° compared to 8.10° (p < 0.001) and 5.32° (p = 0.012). However, there were no significant differences in the front angle compared to the freehand resection group (P = 0.055) and CPSI (P = 0.599) group. The location accuracy observed with FCPSI was maintained at 4 mm, while CPSI and freehand resection exhibited a maximum deviation of 8 mm. CONCLUSION: The fluoroscopically calibrated 3D-printed patient-specific instruments improve the accuracy of osteotomy during bone tumor resection adjacent to joint joints compared to conventional PSI and freehand resection. In conclusion, this novel 3D-printed PSI offers significant accuracy improvement in joint preserving surgery with a minimal increase in time and design costs.