134 research outputs found

    Human-Robot Interaction of a Craniotomy Robot Based on Fuzzy Model Reference Learning Control

    Get PDF
    In this paper, we design a variable admittance controller and propose a variable admittance human-robot cooperative control method based on fuzzy model reference learning. The method is intended to improve the flexible adaptive capability of the robot to assist the surgeon in accomplishing different stages of the task during a craniotomy. First, the method establishes the autoregressive integrated moving average-Kalman filtering-blood pressure (ARIMA-Kalman-BP) model for the drag force prediction by taking the features of natural human arm motion as the reference model of fuzzy learning control, which solves the problem of the features of natural human arm motion being difficult to model. Then the tuning parameter rules for variable virtual damping and virtual mass of the fuzzy conductivity controller are trained by the learning mechanism. Subsequently, the variable conductivity control method based on the tuning of virtual damping and virtual mass parameters is developed by using the robot acceleration and the robot velocity as inputs, and the robot desired velocity and desired acceleration as outputs. The experimental results show that the method can meet the requirement of flexibility; the maximum error of human-machine cooperative velocity is 0.0014 m/s, and the maximum error of human-machine cooperative acceleration is lower than 0.0021 m/s2. Compared with the fuzzy control based on the variable admittance parameter alone, this method has better tracking velocity and acceleration

    Mining Negative Temporal Contexts For False Positive Suppression In Real-Time Ultrasound Lesion Detection

    Full text link
    During ultrasonic scanning processes, real-time lesion detection can assist radiologists in accurate cancer diagnosis. However, this essential task remains challenging and underexplored. General-purpose real-time object detection models can mistakenly report obvious false positives (FPs) when applied to ultrasound videos, potentially misleading junior radiologists. One key issue is their failure to utilize negative symptoms in previous frames, denoted as negative temporal contexts (NTC). To address this issue, we propose to extract contexts from previous frames, including NTC, with the guidance of inverse optical flow. By aggregating extracted contexts, we endow the model with the ability to suppress FPs by leveraging NTC. We call the resulting model UltraDet. The proposed UltraDet demonstrates significant improvement over previous state-of-the-arts and achieves real-time inference speed. To facilitate future research, we will release the code, checkpoints, and high-quality labels of the CVA-BUS dataset used in our experiments.Comment: 10 pages, 4 figures, MICCAI 2023 Early Accep

    Right-sided descending colon with necrotizing enterocolitis: a rare case report

    Get PDF
    BackgroundAnatomical variations of the colon are commonly reported, with the majority involving the right colon. However, anomalies affecting the left colon, particularly the descending colon, are rarely described in the literature.MethodsWe reviewed the clinical records of right-sided descending colon with necrotizing enterocolitis involvement at our hospital, detailing the patients’ onset, imaging studies, complications, and treatment.ResultsA newborn experienced repeated vomiting. Upper and lower gastrointestinal imaging revealed gastroesophageal reflux, the right-sided descending and sigmoid colon. Two weeks later, the infant developed NEC, and after failure of conservative treatment, surgical intervention was performed. We found that the descending colon was fixed to the posterior abdominal wall, extending from the splenic flexure toward the right side and crossing the midline. The entire colon is dilated with thickened walls. Extensive mucosal ulceration is present, accompanied by transmural necrosis. Postoperative pathology reveals significant infiltration of inflammatory cells. The most severely affected regions were the descending and sigmoid colon. Consequently, a total colectomy with end ileostomy was performed, while the distal part of sigmoid colon was preserved. Postoperatively, the newborn recovered well.ConclusionThis case may help raise awareness among surgeons regarding the variability in the position of the descending colon. It is essential to consider such anatomical variations before performing related procedures in this area, to enhance surgical safety and avoid colonic injury

    Morphological and functional characteristics of human gingival junctional epithelium

    Get PDF
    BACKGROUND: This study aims to observe the morphological characteristics and identify the function characteristics of junctional epithelium (JE) tissues and cultured JE cells. METHODS: Paraffin sections of human molar or premolar on the gingival buccolingual side were prepared from 6 subjects. HE staining and image analysis were performed to measure and compare the morphological difference among JE, oral gingival epithelium (OGE) and sulcular epithelium (SE). Immunohistochemistry was applied to detect the expression pattern of cytokeratin 5/6, 7, 8/18, 10/13, 16, 17, 19, and 20 in JE, OGE and SE. On the other hand, primary human JE and OGE cells were cultured in vitro. Cell identify was confirmed by histology and immunohistochemistry. In a co-culture model, TEM was used to observe the attachment formation between JE cells and tooth surface. RESULTS: Human JE was a unique tissue which was different from SE and OGE in morphology. Similarly, morphology of JE cells was also particular compared with OGE cells cultured in vitro. In addition, JE cells had a longer incubation period than OGE cells. Different expression of several CKs illustrated JE was in a characteristic of low differentiation and high regeneration. After being co-cultured for 14 d, multiple cell layers, basement membrane-like and hemidesmosome-like structures were appeared at the junction of JE cell membrane and tooth surface. CONCLUSIONS: JE is a specially stratified epithelium with low differentiation and high regeneration ability in gingival tissue both in vivo and in vitro. In co-culture model, human JE cells can form basement membrane-like and hemidesmosome-like structures in about 2 weeks

    Application and research progress of antibody drug conjugates in HER2 positive advanced gastric cancer

    Get PDF
    Gastric cancer is a malignant tumor with high heterogeneity and invasiveness. Its incidence rate ranks fifth in the world, and its mortality ranks third in the world. Most patients are in a state that cancer cannot be removed by surgery when symptoms appear. At present, systemic treatment is the main treatment for advanced gastric cancer, and human epidermal growth factor receptor 2 (HER2) is one of the important treatment targets for HER2 positive gastric cancer patients. With the continuous optimization of chemotherapy regimen and targeted drugs, the prognosis of some HER2 positive gastric cancer patients has improved significantly. However, the high incidence of drug resistance and high toxicity and side effects are still the bottlenecks limiting the application of HER2 targeted drugs. Therefore, the development of new anti-tumor drugs is of great significance to improve the long-term survival of HER2 positive gastric cancer patients. Antibody drug conjugate (ADC) is a new and efficient anti-tumor drug, which is composed of specific targeted monoclonal antibody, chemical connector and small molecular cytotoxic payload. Its main advantages are strong therapeutic effect and moderate tissue toxicity. In recent years, ADC has set off a huge upsurge in the targeted treatment of HER2 positive advanced gastric cancer. First, after years of development, a variety of ADC including DS-8201 and RC48 have been used in the second- and second-line treatment of gastric cancer. Secondly, with the progress of ADC bioengineering technology, including high proportion of drug antibodies, cleavable linkers, toxic loads that can trigger bystander effect, the new type of ADC can play a more significant therapeutic role in the treatment of specific target tumors, and some of them also have multiple targets and can have anti-tumor effect on multiple specific targets. At the same time, the research and development process of ADC has reached the third stage. The new generation of ADC, through site-specific coupling technology, has higher homogeneity and uniformity, more effective cytotoxic molecules, higher accuracy and lower non-targeted toxicity. In addition, the "targeted immunotherapy" composed of ADC and immune checkpoint inhibitor (ICI) may be a promising treatment strategy for advanced gastric cancer. This article briefly reviewed the application and the latest research progress of ADC in HER2 positive advanced gastric cancer patients in the era of targeted therapy, and discussed the treatment prospects and challenges of ADC combined with ICI in HER2 positive advanced gastric cancer

    Effect of GARP on osteogenic differentiation of bone marrow mesenchymal stem cells via the regulation of TGFβ1 in vitro

    Get PDF
    Mesenchymal stem cells (MSCs), which have multipotential differentiation and self-renewal potential, are possible cells for tissue engineering. Transforming growth factor β1 (TGFβ1) can be produced by MSCs in an inactive form, and the activation of TGFβ1 functions as an important regulator of osteogenic differentiation in MSCs. Recently, studies showed that Glycoprotein A repetitions predominant (GARP) participated in the activation of latent TGFβ1, but the interaction between GARP and TGFβ1 is still undefined. In our study, we successfully isolated the MSCs from bone marrow of rats, and showed that GARP was detected in bone mesenchymal stem cells (BMSCs). During the osteogenic differentiation of BMSCs, GARP expression was increased over time. To elucidate the interaction between GARP and TGFβ1, we downregulated GARP expression in BMSCs to examine the level of active TGFβ1. We then verified that the downregulation of GARP decreased the secretion of active TGFβ1. Furthermore, osteogenic differentiation experiments, alkaline phosphatase (ALP) activity analyses and Alizarin Red S staining experiments were performed to evaluate the osteogenic capacity. After the downregulation of GARP, ALP activity and Alizarin Red S staining significantly declined and the osteogenic indicators, ALP, Runx2, and OPN, also decreased, both at the mRNA and protein levels. These results demonstrated that downregulated GARP expression resulted in the reduction of TGFβ1 and the attenuation of osteoblast differentiation of BMSCs in vitro

    Case Report: Gastric intramural hematoma with acute upper gastrointestinal bleeding in a child

    Get PDF
    Gastric hematoma is an exceptionally rare condition in pediatric patients. It is characterized by the accumulation of blood within the gastric wall, resulting in the formation of a mass. Coagulopathy is the most common cause of gastric hematoma, although other etiologies include gastric ulcer, amyloidosis, pancreatitis, and splanchnic vascular aneurysms. However, the pathophysiology of gastric hematoma remains incompletely understood. It is presumed to be caused by ruptures of the submucosal vessels, leading to dissection of the muscular layer and the formation of a false lumen. Herein, we report the case of a 4 year-old girl who was admitted to our hospital with a large intragastric mass. She presented with hematemesis, and a large hematoma was visualized via gastroscopy. After treatment, the patient underwent a second follow-up gastroscopy, which showed that the gastric mass had subsided, and multiple gastric ulcers were found in the gastric wall. After excluding other causes, we considered that the gastric hematoma may have been caused by the ulcers. By discussing the clinical presentation and treatment options in this case, we hope to improve the understanding of pediatric gastric hematoma so that serious complications can be avoided in future cases

    Efficacy and safety of ultrasound-assisted wound debridement in the treatment of diabetic foot ulcers: a systematic review and meta-analysis of 11 randomized controlled trials

    Get PDF
    ObjectiveResearch data suggests that ultrasound-assisted wound debridement (UAWD) can effectively promote the healing of diabetic foot ulcers (DFU). However, existing research is not consistent with this viewpoint. Therefore, we conducted this study to investigate the effect of UAWD on the healing of diabetic foot ulcers.MethodsFrom the establishment of the database to January 2024, we searched 8 databases to study the effectiveness and safety of UAWD in the treatment of DFU. Two authors independently screened the qualifications of the articles, while two authors extracted relevant data. Statistical analysis was conducted using Review Manager 5.4 and STATA 18.0 software.ResultsA total of 11 randomized controlled studies were included, with 6 countries and 696 participants participating. Our findings showed that UAWD was associated with a significant benefit in healing rate (OR = 2.60, 95% CI: [1.67, 4.03], P < 0.0001, I2 = 25%), wound healing time (MD = -11.94, 95% CI: [-23.65, -0.23], P = 0.05, I2 = 99%), percentage reduction in wound size (MD = 14.2, 95% CI: [10.8, 17.6], P = 0.47, I2 = 32%), effectiveness of treatment (OR = 10.3, 95% CI: [4.68, 22.66], P < 0.00001, I2 = 0%). Moreover, UAWD did not cause any significant adverse reactions. However, there was no obvious difference in wound blood perfusion (MD = 0.25, 95% CI: [-0.01, 0.52], P = 0.06, I2 = 90%), transcutaneous oxygen partial pressure (MD = 14.34, 95% CI: [-10.03, 38.71], P = 0.25, I2 = 98%).ConclusionUAWD can significantly improve wound healing rate, shorten wound healing time, accelerate wound area reduction, and improve clinical treatment effectiveness without significant adverse reactions. Although there is no significant difference in transcutaneous oxygen pressure and wound blood flow perfusion between UAWD and SWC. So we look forward to more scientifically blinded, placebo-controlled, high-quality studies in the future, to enable researchers to obtain more complete and accurate analytical data, in order to improve the scientific and credibility of the evidence.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/, identifier CRD42024501198

    Boosting Superior Lithium Storage Performance of Alloy‐Based Anode Materials via Ultraconformal Sb Coating–Derived Favorable Solid‐Electrolyte Interphase

    Get PDF
    Alloy materials such as Si and Ge are attractive as high‐capacity anodes for rechargeable batteries, but such anodes undergo severe capacity degradation during discharge–charge processes. Compared to the over‐emphasized efforts on the electrode structure design to mitigate the volume changes, understanding and engineering of the solid‐electrolyte interphase (SEI) are significantly lacking. This work demonstrates that modifying the surface of alloy‐based anode materials by building an ultraconformal layer of Sb can significantly enhance their structural and interfacial stability during cycling. Combined experimental and theoretical studies consistently reveal that the ultraconformal Sb layer is dynamically converted to Li3Sb during cycling, which can selectively adsorb and catalytically decompose electrolyte additives to form a robust, thin, and dense LiF‐dominated SEI, and simultaneously restrain the decomposition of electrolyte solvents. Hence, the Sb‐coated porous Ge electrode delivers much higher initial Coulombic efficiency of 85% and higher reversible capacity of 1046 mAh g−1 after 200 cycles at 500 mA g−1, compared to only 72% and 170 mAh g−1 for bare porous Ge. The present finding has indicated that tailoring surface structures of electrode materials is an appealing approach to construct a robust SEI and achieve long‐term cycling stability for alloy‐based anode materials
    corecore