Interpretable CT radiomics model for invasiveness prediction in patients with ground-glass nodules.

AIM: To evaluate the performance of an interpretable computed tomography (CT) radiomic model in predicting the invasiveness of ground-glass nodules (GGNs). MATERIALS AND METHODS: The study was conducted retrospectively from 1 August 2017 to 1 August 2022, at three different centres. Two hundred and thirty patients with GGNs were enrolled at centre I as a training cohort. Centres II (n=157) and III (n=156) formed two external validation cohorts. Radiomics features extracted based on CT were reduced by a coarse-fine feature screening strategy. A radiomic model was developed through the use of the LASSO (least absolute shrinkage and selection operator) and XGBoost algorithms. Then, a radiological model was established through multivariate logistic regression analysis. Finally, the interpretability of the model was explored using SHapley Additive exPlanations (SHAP). RESULTS: The radiomic XGBoost model outperformed the radiomic logistic model and radiological model in assessing the invasiveness of GGNs. The area under the curve (AUC) values for the radiomic XGBoost model were 0.885 (95% confidence interval [CI] 0.836-0.923), 0.853 (95% CI 0.790-0.906), and 0.838 (95% CI 0.773-0.902) in the training and the two external validation cohorts, respectively. The SHAP method allowed for both a quantitative and visual representation of how decisions were made using a given model for each individual patient. This can provide a deeper understanding of the decision-making mechanisms within the model and the factors that contribute to its prediction effectiveness. CONCLUSIONS: The present interpretable CT radiomics model has the potential to preoperatively evaluate the invasiveness of GGNs. Furthermore, it can provide personalised, image-based clinical-decision support.

Catalytically active nanocomposites of electronically coupled carbon nanotubes and platinum nanoparticles formed via vacuum filtration.

Vacuum filtration is employed to fabricate nanocomposite films of single-walled carbon nanotubes and platinum nanoparticles. Characterization by means of x-ray diffraction, electron microscopy, optical spectroscopy, Raman spectroscopy, electrical conductivity measurements, and cyclic voltammetry reveals a well-dispersed morphology and strong electronic coupling between the carbon nanotubes and the platinum nanoparticles. These nanocomposite films are catalytically active and undergo electrical conductivity modulation in the presence of hydrogen, which suggests their utility in a variety of applications including ones in fuel cells, catalysts, and sensors.

[Experimental study and clinical application on osteogenesis of percutaneous autogenous bone marrow grafting in bone defects].

OBJECTIVE: To observe the osteogenesis of percutaneous autogenous bone marrow grafting in cicatricial bone defect, to seek a good method for treating fracture nonunion. METHODS: Eighteen rabbits were adopted in this study. 1 cm bone defect model was made in each side of radius, 6 weeks later, 2 ml autogenous bone marrow was injected in the right radial bone defect as experimental group, 2 ml autogenous peripheral blood in the left side as control group. X-ray features, histologic changes, Ca and P content in the site of bone defect were studied in various times. Also 15 patients were treated clinically for the nonunion fracture, the average time from nonunion to bone marrow grafting was 13 months. RESULTS: In experimental group, the increasing new bone tissue were observed in X-ray and histologic examination. While in control group, no osteogenesis was observed. Ca and P content of experimental group was higher than that of control group. For the 15 patients, 13 cases healed in 5-9 months, 2 cases failed. CONCLUSION: Percutaneous autogenous bone marrow grafting is capable of osteogenesis in the cicatricial bone defects. It can be used in nonunion cases which are not fit for operation of bone grafting because of poor condition of the skin.

[A new method of bone defect repairing after bone cyst curettage].

OBJECTIVE: To introduce a new method of bone defect repairing after bone cyst curettage. METHODS: Eight cases with bone cyst were treated with this new method. The pieces of autogenous periosteum were implanted into the hematoma within the enveloped bone defect created after the bone cyst curettage. Among these patients, there were 5 males and 3 females, aged from 14 to 36 years old. All the lesions located in the upper of femur except one being located in humerus. The results were evaluated through the postoperative radiological findings with the preoperative ones and analysis of clinical functions. RESULTS: All the patients were followed up for 2 to 11 years. X-ray films showed that osteogenesis developed well and that the enveloped bone defects had been repaired. No recurrence was found and the function of the affected limbs were maintained. CONCLUSION: Autogenous periosteum grafting is effective in the treatment of solitary bone cyst.

Regulation of internodal lenght by peroxidase enzymes in grain sorghum.

A relationship between height genes (dw locus) and perioxidase was demonstrated by extracting and determining peroxidase specific activity in internode tissue from different height isogenic lines of sorghum Sorghum bicolor (L.) Moench]. Tall plants (2 dwarf) had less peroxidase per gram tissue than their short counterparts (3 dwarf); their F1 offspring internodes were closer but had more peroxidase than the tall parent. Peroxidase in the F2 offspring was inversely related to their height and followed a simply-inherited pattern similar to that for height.Among different tissues analyzed, peroxidase concentration in roots was higher than in leaves and internodes, whole internode higher than in pith, and seed embryo higher than in endosperm. Peroxidase activity of nonviable seeds was negligible.Isoelectric focusing provided a more detailed peroxidase zymogram than did gel electrophoresis. Differences in peroxidase bands among tall and short parental plants, F1 and F2 segregating groups all appear to be reflected by intensity differences rather than by position or number of bands.Activities of nitrate reductase and acid phosphatase did not correlate with height. That finding provides a control and suggests that peroxidase activity is not associated with height by chance but may have a functional relationship.