Arthroscopic surgery for ankle gouty arthritis: a retrospective analysis of clinical outcomes at six month follow-up based on a novel classification system.

PURPOSE: This study aimed to evaluate the clinical outcomes, patient-reported outcomes, and recurrence rate of patients diagnosed with ankle gouty arthritis who underwent arthroscopic surgery based on the new classification. METHODS: A total of 51 patients diagnosed with ankle gouty arthritis were included in this retrospective study. A new classification was proposed based on the location and extent of MSU crystal deposition under an arthroscopy view. Patients are classified into different types and underwent arthroscopic surgery accordingly. The primary outcome measure was the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score. The secondary outcomes included the visual analog pain scale (VAS), serum uric acid levels, and the recurrence rate of ankle gouty arthritis at one year postoperatively. RESULTS: Based on the new classification, five patients were Type I, 24 patients were Type II, five were Type III A, six were Type III B, and 11 were Type IV. The average follow-up time was 23.5 ± 10.9 months. The AOFAS hindfoot-ankle score improved significantly from 70.3 ± 15.9 to 85.6 ± 13.0 (p < 0.01). The mean serum uric acid level was significantly decreased from 442.0 ± 109.2 to 540.5 ± 132.4 (p < 0.01). The average VAS scale decreased from 3.8 ± 1.9 to 1.4 ± 1.7 (p < 0.01). The median of recurrences in one year postoperatively was significantly decreased from 1.5 (1, 3.75) to 0 (0, 0.75) (p < 0.01). CONCLUSION: A new classification strategy for ankle gouty arthritis based on arthroscopic view was proposed. Patients with ankle gouty arthritis showed significant improvement in ankle function and pain relief after undergoing arthroscopic surgery driven by the new classification.

Human Fallopian Tube-Derived Organoids with TP53 and RAD51D Mutations Recapitulate an Early Stage High-Grade Serous Ovarian Cancer Phenotype In Vitro.

RAD51D mutations have been implicated in the transformation of normal fallopian tube epithelial (FTE) cells into high-grade serous ovarian cancer (HGSOC), one of the most prevalent and aggressive gynecologic malignancies. Currently, no suitable model exists to elucidate the role of RAD51D in disease initiation and progression. Here, we established organoids from primary human FTE and introduced TP53 as well as RAD51D knockdown to enable the exploration of their mutational impact on FTE lesion generation. We observed that TP53 deletion rescued the adverse effects of RAD51D deletion on the proliferation, stemness, senescence, and apoptosis of FTE organoids. RAD51D deletion impaired the homologous recombination (HR) function and induced G2/M phase arrest, whereas concurrent TP53 deletion mitigated G0/G1 phase arrest and boosted DNA replication when combined with RAD51D mutation. The co-deletion of TP53 and RAD51D downregulated cilia assembly, development, and motility, but upregulated multiple HGSOC-associated pathways, including the IL-17 signaling pathway. IL-17A treatment significantly improved cell viability. TP53 and RAD51D co-deleted organoids exhibited heightened sensitivity to platinum, poly-ADP ribose polymerase inhibitors (PARPi), and cell cycle-related medication. In summary, our research highlighted the use of FTE organoids with RAD51D mutations as an invaluable in vitro platform for the early detection of carcinogenesis, mechanistic exploration, and drug screening.

[Tibiotalocalcaneal arthrodesis for end-stage ankle and hindfoot arthropathy: Short- and mid-term clinical outcomes].

OBJECTIVE: To analyze the clinical data of patients with end-stage ankle and hindfoot arthropathy who underwent tibiotalocalcaneal (TTC) arthrodesis by the same surgeon, explore the short- and mid-term clinical results, complications and functional improvement, and discuss the clinical prognosis and precautions of TTC arthrodesis. METHODS: Retrospective analysis was made on the clinical data of 40 patients who underwent TTC arthrodesis by the same surgeon from March 2011 to December 2020. In this study, 23 males and 17 females were included, with an average age of (49.1±16.0) years. All the patients underwent unilateral surgery. The clinical characteristics, imaging manifestations, main diagnosis and specific surgical techniques of the patients were recorded. The clinical outcomes were evaluated by comparison of the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and visual analogue scale (VAS) between pre-operation and at the last follow-up. The fusion healing time, symptom improvement (significant improvement, certain improvement, no improvement or deterioration) and postoperative complications were also recorded. RESULTS: The median follow-up time was 38.0 (26.3, 58.8) months. The preoperative VAS score was 6.0 (4.0, 7.0), and the AOFAS score was 33.0 (25.3, 47.3). At the last follow-up, the median VAS score was 0 (0, 3.0), and the AOFAS score was 80.0 (59.0, 84.0). All the significantly improved compared with their preoperative corresponding values (P < 0.05). There was no wound necrosis or infection in the patients. One patient suffered from subtalar joint nonunion, which was syphilitic Charcot arthropathy. The median bony healing time of other patients was 15.0 (12.0, 20.0) weeks. Among the included patients, there were 25 cases with significant improvement in symptom compared with that preoperative, 8 cases with certain improvement, 4 cases with no improvement, and 3 cases with worse symptoms than that before operation. CONCLUSION: TTC arthrodesis is a reliable method for the treatment of the end-stage ankle and hindfoot arthropathy. The function of most patients was improved postoperatively, with little impact on daily life. The causes of poor prognosis included toe stiffness, stress concentration in adjacent knee joints, nonunion and pain of unknown causes.

Analysis of radiologic parameters and clinical outcomes in supramalleolar osteotomy for varus ankle osteoarthritis: A novel method for evaluating ankle alignment.

BACKGROUND: Solely relying on the tibial ankle surface (TAS) angle for determining the mechanical ankle axis might be insufficient. We introduce a novel method to determine the distance from the center of the talus to the tibial axis (TTD). This study aimed to investigate the association between clinical outcomes and radiological changes before and after supramalleolar osteotomy (SMO), including TAS angle, talar tilt (TT) angle, tibiotalar surface (TTS) angle and TTD. METHODS: Seventy patients who received SMO were enrolled. Radiological changes were measured using weight-bearing anteroposterior imaging. The percentage of talar center displacement (TTDP) was calculated as the difference between postoperative and preoperative TTD, divided by talar width (TW). Clinical assessments were performed using the American Orthopedic Foot and Ankle Society ankle-hindfoot (AOFAS) scale. Differences in the aforementioned indicators before and after the operation were analyzed. We defined ΔAOFAS, ΔTAS, ΔTT and ΔTTS as the difference between postoperative and preoperative values. RESULTS: ΔTTS correlated with ΔAOFAS (r = 0.40, p = 0.008), as did TTDP (r = 0.32, p = 0.035). No correlation was observed between ΔAOFAS and ΔTAS. In the comparison between groups, patients with a TTDP greater than 26.19 exhibited a significantly greater ΔAOFAS. The high intraclass correlation coefficient indicated good reliability of the novel method. CONCLUSION: Solely relying on the TAS angle for tibial correction was insufficient. We found TTD as a novel method to evaluate mechanical ankle joint axis. TTDP and ΔTTS both positively correlated with ΔAOFAS, indicating the usefulness of these radiologic parameters.

Denoising brain networks using a fixed mathematical phase change in independent component analysis of magnitude-only fMRI data.

Brain networks extracted by independent component analysis (ICA) from magnitude-only fMRI data are usually denoised using various amplitude-based thresholds. By contrast, spatial source phase (SSP) or the phase information of ICA brain networks extracted from complex-valued fMRI data, has provided a simple yet effective way to perform the denoising using a fixed phase change. In this work, we extend the approach to magnitude-only fMRI data to avoid testing various amplitude thresholds for denoising magnitude maps extracted by ICA, as most studies do not save the complex-valued data. The main idea is to generate a mathematical SSP map for a magnitude map using a mapping framework, and the mapping framework is built using complex-valued fMRI data with a known SSP map. Here we leverage the fact that the phase map derived from phase fMRI data has similar phase information to the SSP map. After verifying the use of the magnitude data of complex-valued fMRI, this framework is generalized to work with magnitude-only data, allowing use of our approach even without the availability of the corresponding phase fMRI datasets. We test the proposed method using both simulated and experimental fMRI data including complex-valued data from University of New Mexico and magnitude-only data from Human Connectome Project. The results provide evidence that the mathematical SSP denoising with a fixed phase change is effective for denoising spatial maps from magnitude-only fMRI data in terms of retaining more BOLD-related activity and fewer unwanted voxels, compared with amplitude-based thresholding. The proposed method provides a unified and efficient SSP approach to denoise ICA brain networks in fMRI data.

Efficient Fabrication of Carbon Nanotube-Based Stretchable Electrodes for Flexible Electronic Devices.

Stretchable electrodes are highly demanded in various wearable and flexible electronic devices, whereas the efficient fabrication approach is still a challenge. In this work, an efficient shrinking method to fabricate carbon nanotube (CNT)-based stretchable electrodes is proposed. The electrode is a layer of anisotropic CNT wrinkling film coated on a latex balloon substrate (CNT@latex), whose resistivity remains stable after 25 000 stretching cycles of 0 to 50% tensile strain, and can survive up to 500% tensile train. The highly conductive electrode can be used as the current collector of a stretchable Zinc-ion battery, maintaining an output voltage of 1.3 V during the stretching process of 0 to 100%. The applications of the electrode in flexible triboelectric nanogenerators and Joule heating devices are also demonstrated, further indicating their good prospects in the field of stretchable electronic devices.

A review of the structure, function, and application of plant-based protein-phenolic conjugates and complexes.

Interactions between plant-based proteins (PP) and phenolic compounds (PC) occur naturally in many food products. Recently, special attention has been paid to the fabrication of PP-PC conjugates or complexes in model systems with a focus on their effects on their structure, functionality, and health benefits. Conjugates are held together by covalent bonds, whereas complexes are held together by noncovalent ones. This review highlights the nature of protein-phenolic interactions involving PP. The interactions of these PC with the PP in model systems are discussed, as well as their impact on the structural, functional, and health-promoting properties of PP. The PP in conjugates and complexes tend to be more unfolded than in their native state, which often improves their functional attributes. PP-PC conjugates and complexes often exhibit improved in vitro digestibility, antioxidant activity, and potential allergy-reducing activities. Consequently, they may be used as antioxidant emulsifiers, edible film additives, nanoparticles, and hydrogels in the food industry. However, studies focusing on the application of PP-PC conjugates and complexes in real foods are still scarce. Further research is therefore required to determine the structure-function relationships of PP-PC conjugates and complexes that may influence their application as functional ingredients in the food industry.

Phylogeny of Graphostromatacea with two new species (Biscogniauxia glaucae sp. nov. and Graphostroma guizhouensis sp. nov.) and new record of Camillea broomeana isolated in China.

In the process of studying the diversity of Xylariales in China, three species owning characteristics of Graphostromataceae were observed in China. Morphology of the described species with illustrations and their phylogeny based on regions of internal transcribed spacers (ITS), the second-largest subunit of the RNA polymerase II (RPB2), ß-tubulin (TUB2) and α-actin (ACT) are provided. Two new species and one new record from China are identified. Morphologically, Biscogniauxia glaucae sp. nov. differs from B. atropunctata var. maritima, B. citriformis var. macrospora, B. fuscella and B. mediterranea by its stromata with raised margins, clear outlines, punctate ostioles openings and ascospores which are equilateral with broadly rounded ends, a straight spore-length germ slit on the more concave side, lacking appendages and sheathes. Graphostroma guizhouensis is identified as a new species based on the multi-gene phylogenetic tree. Camillea broomeana with scanning electron microscope description of ascospores is illustrated as a new record from China. Cryptostroma is proposed in Graphostromataceae based on molecular data. Vivantia is accepted in Graphostromataceae based on its morphological characteristics and Nodulisporiurn anamorphs which are similar to those of Biscogniauxia.

Effects of Dissolved Organic Matter on the Bioavailability of Heavy Metals During Microbial Dissimilatory Iron Reduction: A Review.

Dissolved organic matter (DOM), a type of mixture containing complex structures and interactions, has important effects on environmental processes such as the complexation and interface reactions of soil heavy metals. Furthermore, microbial dissimilatory iron reduction (DIR), a key process of soil biogeochemical cycle, is closely related to the migration and transformation of heavy metals and causes the release of DOM by carbon-ferrihydrite associations. This chapter considers the structural properties and characterization techniques of DOM and its interaction with microbial dissimilated iron. The effect of DOM on microbial DIR is specifically manifested as driving force properties, coprecipitation, complexation, and electronic shuttle properties. The study, in addition, further explored the influence of pH, microorganisms, salinity, and light conditions, mechanism of DOM and microbial DIR on the toxicity and bioavailability of different heavy metals. The action mechanism of these factors on heavy metals can be summarized as adsorption coprecipitation, methylation, and redox. Based on the findings of the review, future research is expected to focus on: (1) The combination of DOM functional group structure analysis with high-resolution mass spectrometry technology and electrochemical methods to determine the electron supply in the mechanism of DOM action on DIR; (2) Impact of DOM on differences in structure and functions of plant rhizosphere in heavy metal contaminated soil; and (3) Bioavailability of DOM-dissociative iron-reducing bacteria-heavy metal ternary binding on rhizosphere heavy metals under dynamic changes of water level from the perspective of the differences in DOM properties, such as polarity, molecular weight, and functional group.

The structure and regulation of the E3 ubiquitin ligase HUWE1 and its biological functions in cancer.

E3 ligases are a class of critical enzymes that can catalyse the transfer of ubiquitin (Ub) from an E2 enzyme to the substrate and are essential to cellular processes. The E3 ligase HUWE1 (also known as ARF-BP1, HECTH9, HSPC272, Ib772, LASU1, MULE, URE-B1, UREB1, and HECT, UBA and WWE domain-containing E3 ubiquitin protein ligase 1) is encoded by the huwe1 gene. HUWE1 is a key regulator of the DNA damage response, transcription, autophagy, apoptosis and metabolism in a variety of cancers. Due to its pivotal role in conferring substrate specificity, HUWE1 has attracted enormous attention as a promising anticancer drug target. In this review, we indicate the specific molecular structure of HUWE1 and its role in various cellular signalling pathways and highlight new insights into HUWE1 in cancer. Finally, we discuss outstanding questions regarding HUWE1 in oncology and highlight its limitations in drug development and clinical guidance to better define the role of HUWE1 in multiple cancers.

Spatial source phase: A new feature for identifying spatial differences based on complex-valued resting-state fMRI data.

Spatial source phase, the phase information of spatial maps extracted from functional magnetic resonance imaging (fMRI) data by data-driven methods such as independent component analysis (ICA), has rarely been studied. While the observed phase has been shown to convey unique brain information, the role of spatial source phase in representing the intrinsic activity of the brain is yet not clear. This study explores the spatial source phase for identifying spatial differences between patients with schizophrenia (SZs) and healthy controls (HCs) using complex-valued resting-state fMRI data from 82 individuals. ICA is first applied to preprocess fMRI data, and post-ICA phase de-ambiguity and denoising are then performed. The ability of spatial source phase to characterize spatial differences is examined by the homogeneity of variance test (voxel-wise F-test) with false discovery rate correction. Resampling techniques are performed to ensure that the observations are significant and reliable. We focus on two components of interest widely used in analyzing SZs, including the default mode network (DMN) and auditory cortex. Results show that the spatial source phase exhibits more significant variance changes and higher sensitivity to the spatial differences between SZs and HCs in the anterior areas of DMN and the left auditory cortex, compared to the magnitude of spatial activations. Our findings show that the spatial source phase can potentially serve as a new brain imaging biomarker and provide a novel perspective on differences in SZs compared to HCs, consistent with but extending previous work showing increased variability in patient data.

A new method to measure the semantic similarity from query phenotypic abnormalities to diseases based on the human phenotype ontology.

BACKGROUND: Although rapid developed sequencing technologies make it possible for genotype data to be used in clinical diagnosis, it is still challenging for clinicians to understand the results of sequencing and make correct judgement based on them. Before this, diagnosis based on clinical features held a leading position. With the establishment of the Human Phenotype Ontology (HPO) and the enrichment of phenotype-disease annotations, there throws much more attention to the improvement of phenotype-based diagnosis. RESULTS: In this study, we presented a novel method called RelativeBestPair to measure similarity from the query terms to hereditary diseases based on HPO and then rank the candidate diseases. To evaluate the performance, we simulated a set of patients based on 44 complex diseases. Besides, by adding noise or imprecision or both, cases closer to real clinical conditions were generated. Thus, four simulated datasets were used to make comparison among RelativeBestPair and seven existing semantic similarity measures. RelativeBestPair ranked the underlying disease as top 1 on 93.73% of the simulated dataset without noise and imprecision, 93.64% of the simulated dataset with noise and without imprecision, 39.82% of the simulated dataset without noise and with imprecision, and 33.64% of the simulated dataset with both noise and imprecision. CONCLUSION: Compared with the seven existing semantic similarity measures, RelativeBestPair showed similar performance in two datasets without imprecision. While RelativeBestPair appeared to be equal to Resnik and better than other six methods in the simulated dataset without noise and with imprecision, it significantly outperformed all other seven methods in the simulated dataset with both noise and imprecision. It can be indicated that RelativeBestPair might be of great help in clinical setting.

Transmissive terahertz metalens with full phase control based on a dielectric metasurface.

In this paper, we report a transmissive terahertz (THz) metalens based on a dielectric metasurface that consists of periodically arranged sub-wavelength silicon cross resonators with a spatially hyperboloidal phase profile. By varying arm lengths of the cross resonators, we obtained a full 2π phase coverage with high transmission at target frequency. The fabricated metalens was experimentally demonstrated to focus a continuous THz beam to a spot with a full width at half-maximum of 630 µm at a focal length of 28 mm, which agrees well with the theoretical calculation. This device has potential for applications in THz imaging and communications, and our work can also easily be extended in the design of other planar THz components, such as beam deflectors or vortex plates.

Comparison of total costs between internal fixation and hemiarthroplasty for displaced femoral neck fractures.

BACKGROUND: There is very little information on the costs of different surgeries for displaced femoral neck fractures. This study aimed to compare the costs between internal fixation and hemiarthroplasty (HA) in the treatment of displaced femoral neck fracture. METHOD: A total of 142 patients aged 65 years or older who had been randomized into internal fixation group (n = 70) or HA group (n = 72) were followed for 2 years. Cost data was collected through hospitalization information, cost diary and telephone interview. Sensitivity analysis was performed for missing diaries. The total costs were collected and compared between the two groups. RESULTS: All diaries were completed by 69.7% of patients. The mean costs of primary treatment were significantly lower for internal fixation (CNY 21,631) compared with HA (CNY 51,641) (p < 0.001). The mean post-discharge costs were similar for both procedures: CNY 37,377 for internal fixation and CNY 34,981 for HA (p = 0.640). The mean total costs for internal fixation were CNY 59,008, which was significantly lower than the mean total costs of CNY 86,622 for HA (p = 0.002). CONCLUSION: Although the post-discharge costs of internal fixation were slightly higher, the total costs were still lower than for HA due to great variance in costs of primary treatment. In China, internal fixation may be less costly than HA for displaced femoral neck fracture treatment.

The effect of iron plaque on lead translocation in soil-Carex cinerascens kukenth. system.

A pot experiment was conducted to investigate the effect of iron plaque on Pb uptake by and translocation in Carex cinerascens Kukenth. grown under open-air conditions. Using Scanning Electron Microscopy and Energy Dispersive X-Ray Spectrometry, iron plaque was present as an amorphous coating on root surfaces with uneven distribution. The amount of iron plaque increased significantly with increasing Fe additions regardless of Pb additions. The presence of iron plaque on the root surface of Carex cinerascens Kukenth. increased the concentrations of Pb adsorbed by iron plaque. The Pb percentage in whole roots increased by 14.52% at 500 mg kg(-1) Fe treatment than at 0 mg kg(-1) Fe, and the distribution coefficient (DC) of Pb and translocation factor (TF) root increased with Fe additions, but translocation factor (TF) shoot decreased with Fe additions. The results suggested that iron plaque could promote the translocation of Pb from soil to roots to some extent, and it played a role to reduce heavy metals pollution of Poyang Lake wetland.

[Diagnosis and management of atypical femoral fractures: clinical efficacy in 11 cases].

OBJECTIVE: To evaluate the clinical efficacy of intramedullary nail fixation in atypical femoral fractures and explore the management approach. METHOD: From January 2010 to December 2014, a total of 116 patients over 60 years old with femoral intertrochanteric fractures or femoral shaft fractures were treated in Department of Orthopaedics and Traumatology. Among the patients, 11 with atypical femoral fractures, aged from 62 to 82 ( 69.3±5.6) years old, received surgical treatments. There were 2 males (18.2%) and 9 females (81.8%). 5 patients (45.5%) had the prodromal symptom of thigh pain. 9 patients (81.8%) had the history of long-term use of bisphosphonates with the duration of 3 to 9 (5.3±2.1) years. All the fractures received close reduction and antegrade intramedullary nail fixation. The Thoresen score and EuroQol 5 dimensions scores (EQ-5D) were applied to evaluate the extremity function and life quality after surgery. RESULT: All the operations were performed successfully. At least 1 years follow-up was accomplished with the follow-up period of 1 to 4 (1.8±0.9) years. There were 8 (72.7%) excellent, 2 (18.2%) good, 1 (9.1%) fair according to the Thoresen score with total excellent to good rate up to 90.9% at the last follow-up. The EQ-5D scores showed the life quality was similar with that before injury (P>0.05). Fracture healing was achieved in all 11 cases with time from 3 to 8 (5.7±1.6) month. There was no case complicated with infection, nonunion or implant failure during the follow-up period. No contralateral atypical femoral fracture was observed. CONCLUSION: Atypical femoral fractures are uncommon in the clinical practice. Accurate diagnosis and appropriate management approach are the keys of satisfactory outcomes.

[Preliminary analysis of total cost and life quality for elder patients with femoral neck fracture].

OBJECTIVE: To analyze the total cost and life quality of the femoral neck fracture patients who received different surgery and supplement comprehensive data of osteoporotic fracture. METHODS: One hundred and five patients above 60-year old who were diagnosed femoral neck fracture and received operation in Department of Orthopedics ＆ Traumatology, Beijing Jishuitan Hospital were admitted into our study from August 2013 to December. According to the type of surgery there were 52 and 53 cases in internal fixation (IF) group and hemiarthroplasty (HA) group respectively. At first we collected the medical expense of the patients before and during hospitalization. And then the 1-year medical and non-medical expenses were collected by the cost diary ever 3 months after discharge. At the last follow-up we evaluated the life quality by the EuroQol-5 Dimensions (EQ-5D) and calculated the total cost. Outcome All the patients completed the operation successfully. No nonunion or delayed union cases in IF group, and no cases received revision surgery in both groups. The total average cost was 59 584.9 yuan including 79.1% medical cost and 20.9% non-medical cost. The primary treatment cost accounts for 84.1% of the medical cost. The cost for home care accounts for 90.7% of the non-medical care. The total and medical cost of IF group just account for 40.3% and 38.5% of the HA group and the non-medical showed no significant difference between the 2 groups (P>0.05). In addition the data of life quality and walking capability also showed no significant difference. CONCLUSION: The main cost for the femoral neck fracture is medical expense in 1-year follow-up. Both surgeries can provide satisfactory outcome, however IF may be more cost-effective compared to the HA because of the less total cost.

Current surgical status of hip fracture among elderly in China.

OBJECTIVE: Hip fracture patients are recommended to undergo surgery within 24-36 h. The present study aimed to analyze the current status of hip fracture surgery among the elderly in China. METHODS: The baseline information, such as the patient's age, gender, place of residence, place of treatment, fracture type, admission, and operation time, of hip fracture patients >65-years-old were retrieved from the hospital quality monitoring system (HQMS) database from 2013 to 2017 and analyzed. RESULTS: A total of 304,279 patients >65-years-old with hip fractures were included in this study. The average length of hospital stay was 15 days, and the average waiting time for surgery after admission was 96 h. The average surgery rate of elderly hip fractures in China was 59.6 %, of which the lowest was recorded in the Northwest China (46.4 %). CONCLUSIONS: The major issues in diagnosing and treating elderly patients with hip fractures in China are the long waiting time for surgery and the low surgery rate.

3D Models of Sarcomas: The Next-generation Tool for Personalized Medicine.

Sarcoma is a complex and heterogeneous cancer that has been difficult to study in vitro. While two-dimensional (2D) cell cultures and mouse models have been the dominant research tools, three-dimensional (3D) culture systems such as organoids have emerged as promising alternatives. In this review, we discuss recent developments in sarcoma organoid culture, with a focus on their potential as tools for drug screening and biobanking. We also highlight the ways in which sarcoma organoids have been used to investigate the mechanisms of gene regulation, drug resistance, metastasis, and immune interactions. Sarcoma organoids have shown to retain characteristics of in vivo biology within an in vitro system, making them a more representative model for sarcoma research. Our review suggests that sarcoma organoids offer a potential path forward for translational research in this field and may provide a platform for developing personalized therapies for sarcoma patients.

A finite element model of human hindfoot and its application in supramalleolar osteotomy.

BACKGROUND: The majority of the ankle osteoarthritis cases are posttraumatic and affect younger patients with a longer projected life span. Hence, joint-preserving surgery, such as supramalleolar osteotomy becomes popular among young patients, especially those with asymmetric arthritis due to alignment deformities. However, there is a lack of biomechanical studies on postoperative evaluation of stress at ankle joints. We aimed to construct a verifiable finite element model of the human hindfoot, and to explore the effect of different osteotomy parameters on the treatment of varus ankle arthritis. METHODS: The bones of the hindfoot are reconstructed using normal CT tomography data from healthy volunteers, while the cartilages and ligaments are determined from the literature. The finite element calculation results are compared with the weight-bearing CT (WBCT) data to validate the model. By setting different model parameters, such as the osteotomy height (L) and the osteotomy distraction distance (h), the effects of different surgical parameters on the contact stress of the ankle joint surface are compared. FINDINGS: The alignment and the deformation of hindfoot bones as determined by the finite element analysis aligns closely with the data obtained from WBCT. The maximum contact stress of the ankle joint surface calculated by this model increases with the increase of the varus angle. The maximum contact stresses as a function of the L and h of the ankle joint surface are determined. INTERPRETATION: The relationship between surgical parameters and stress at the ankle joint in our study could further help guiding the planning of the supramalleolar osteotomy according to the varus/valgus alignment of the patients.