Model development to predict central lymph node metastasis in cN0 papillary thyroid microcarcinoma by machine learning.

Background: Whether prophylactic central lymph node dissection is necessary for cN0 papillary thyroid microcarcinoma (PTMC) patients remains highly debatable. Surgeons desperately need a way to help with surgical decision-making. While traditional predictive models can better explain changes in variables, machine learning (ML) models may have better predictive performance. This study aims to develop models for predicting the risk of central lymph node metastasis (CLNM) by utilizing ML algorithms. Methods: The clinical records of 1,121 patients with cN0 PTMC who underwent initial thyroid resection at our hospital between January 2014 and December 2018 were retrospectively retrieved. Univariate and multivariate analyses were performed to examine risk factors associated with CLNM. Six ML algorithms for predicting CLNM were established and internally validated. Indices including the area under the receiver operating characteristic (AUROC), sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were calculated to test the performance of the model. Results: The results showed 33.5% (376 out of 1,121) of patients had CLNM. In multivariate logistic regression (LR) analyses, gender, age, tumor size, multifocal lesions, and extrathyroidal extension (ETE) were all independent predictors of CLNM. The AUROC predictive values of the six ML algorithms were between 0.664 and 0.794, with the random forest (RF) model performing the best with an AUROC of 0.794. Therefore, we used the RF model and uploaded the results to a web-based risk calculator to predict an individual's probability of CLNM (https://xijing-thyroid.shinyapps.io/ptmc_clnm). Conclusions: Developing predictive models of CLNM in cN0 PTMC patients using the ML algorithm is a feasible method. Our online risk calculator based on the RF model may be a useful tool for surgical decisions.

Posterior Lumbar Plexus Block Anesthesia for Elderly Patients with Lower Limb Fracture.

The incidence rate of lower limb fractures is high and has increased over the recent years, which affects the physical and mental health and the daily activities of patients. Lower limb fractures are often treated surgically. Therefore, an effective anesthesia regimen is crucial for a smooth and stable operation. To investigate the efficacy of posterior lumbar plexus block anesthesia during surgery for elderly patients with lower extremity fractures. In total, patients were divided into study and control groups. Anesthesia was administered by posterior lumbar plexus nerve block in the study group and epidural anesthesia in the control group. Hemodynamic parameters, anesthesia condition, pain level (VAS), and adverse effects were measured in both groups before anesthesia (T0), at anesthesia induction (T1), 30 min into the operation (T2), and at the end of the operation (T3). At T0, there were no significant differences in MAP and HR between the study and control groups. However, MAP and HR in the study group were significantly lower than those in the control group at T1, T2, and T3. The BIS value of the study group at each time point after anesthesia was significantly lower than that of the control group. The onset and induction time of anesthesia in the study group were also significantly shorter than those in the control group. Preoperative VAS scores did not differ between the study and control groups. However, the VAS scores of the study group at each time point were significantly lower than those of the control group. There was no significant difference in the incidence of adverse reactions between the two groups. Our results suggest that anesthesia with posterior lumbar plexus block surgery for lower extremity fractures in elderly patients can maintain hemodynamic stability and reduce block onset time, anesthesia induction time, and pain.

Compact fiber-free parallel-plane multi-wavelength diffuse optical tomography system for breast imaging.

To facilitate the clinical applicability of the diffuse optical inspection device, a compact multi-wavelength diffuse optical tomography system for breast imaging (compact-DOTB) with a fiber-free parallel-plane structure was designed and fabricated for acquiring three-dimensional optical properties of the breast in continuous-wave mode. The source array consists of 56 surface-mounted micro light-emitting diodes (LEDs), each integrating three wavelengths (660, 750, and 840 nm). The detector array is arranged with 56 miniaturized surface-mounted optical sensors, each encapsulating a high-sensitivity photodiode (PD) and a low-noise current amplifier with a gain of 24×. The system provides 3,136 pairs of source-detector measurements at each wavelength, and the fiber-free design largely ensures consistency between source/detection channels while effectively reducing the complexity of system operation and maintenance. We have evaluated the compact-DOTB system's characteristics and demonstrated its performance in terms of reconstruction positioning accuracy and recovery contrast with breast-sized phantom experiments. Furthermore, the breast cancer patient studies have been carried out, and the quantitative results indicate that the compact-DOTB system is able to observe the changes in the functional tissue components of the breast after receiving the neoadjuvant chemotherapy (NAC), demonstrating the great potential of the proposed compact system for clinical applications, while its cost and ease of operation are competitive with the existing breast-DOT devices.

Iodine intake level and incidence of thyroid disease in adults in Shaanxi province: a cross-sectional study.

BACKGROUND: Exploring the relationship between adult iodine intake level and thyroid disease in Shaanxi area is of great significance for adult scientific iodine supplement and individual iodine supplement strategy. At present, the relationship between iodine and incidence of thyroid disease has not been determined. METHODS: This study was based on the clinical data of 1,159 patients from the Shaanxi Province aged over 18 years and diagnosed with thyroid-related diseases who were admitted to the Xijing Hospital from 2016 to 2020, and 182 provincial healthy volunteers aged over 18 years who agreed and signed informed consent for physical examination in 2020. The chi-square test and nonparametric test were used to investigate the relationship between iodine intake level and thyroid disease. RESULTS: (I) A total of 1,341 patients were enrolled and observed in this study. The median urinary iodine (MUI) was 233.20 µg/L. Compared with the control, group participants the urine iodine (UI) of those with hyperthyroidism, Hashimoto's thyroiditis (HT), papillary thyroid cancer (PTC), and benign nodules was significantly different (P<0.05). (II) The incidence of PTC was higher in women with excessive iodine intake and people aged ≥45 years (P<0.05). (III) There was no significant difference in urinary iodine (UI), age, gender, and other factors between benign nodules and PTC (P>0.05). CONCLUSIONS: The iodine intake level of adults in Shaanxi is high, which is related to hyperthyroidism, HT, benign nodules, thyroid cancer, and other diseases. There were 3 factors, including excessive iodine intake, age ≥45 years, and female gender, found to be associated with the development of PTC.

Analytical model for effects of capsule shape on the healing efficiency in self-healing materials.

The fundamental requirement for the autonomous capsule-based self-healing process to work is that cracks need to reach the capsules and break them such that the healing agent can be released. Ignoring all other aspects, the amount of healing agents released into the crack is essential to obtain a good healing. Meanwhile, from the perspective of the capsule shapes, spherical or elongated capsules (hollow tubes/fibres) are the main morphologies used in capsule-based self-healing materials. The focus of this contribution is the description of the effects of capsule shape on the efficiency of healing agent released in capsule-based self-healing material within the framework of the theory of geometrical probability and integral geometry. Analytical models are developed to characterize the amount of healing agent released per crack area from capsules for an arbitrary crack intersecting with capsules of various shapes in a virtual capsule-based self-healing material. The average crack opening distance is chosen to be a key parameter in defining the healing potential of individual cracks in the models. Furthermore, the accuracy of the developed models was verified by comparison to the data from a published numerical simulation study.

[Impact of serum α-fetoprotein level on short-term recurrence after R0 resection in primary hepatocellular carcinoma].

OBJECTIVE: To investigate the impact of serum α-fetoprotein (AFP) level on survival and short-term recurrence after R0 resection in primary hepatocellular carcinoma (HCC). METHODS: The clinical data of 582 cases of primary HCC underwent R0 resection from January 1997 to December 2009 was analyzed retrospectively. There were 488 male and 94 female patients whose average age was 51 years (ranging from 31 to 73 years). The survival rate of 1-, 3- and 5-year and clinopathological factors between the AFP-negative group and AFP-positive group were compared. The risk factors of short-term recurrence after R0 resection of HCC patients in AFP-positive group were further analyzed. RESULTS: The age and histological differentiation in AFP-positive group were significantly lower than the AFP-negative group (χ(2) = 11.004, 32.293; P = 0.000). Otherwise the serum γ-glutamyl transferase level, diameter of tumor, TNM stage and short-term recurrence were higher than the AFP-negative group (χ(2) = 9.814 to 14.009, P < 0.05) , and solitary HCC in AFP-positive group was less than AFP-negative group (χ(2) = 8.509, P = 0.004). Survival analysis showed that overall survival rate of 1-, 3- and 5- year were 80.5%, 53.9%, 40.2% and 89.2%, 69.8%, 50.3% in the AFP-positive group and AFP-negative group, respectively (χ(2) = 11.884, P = 0.001), and the disease-free survival rate of 1-, 3- and 5- year were 65.6%, 38.4%, 29.6% and 81.7%, 51.0%, 42.1% (χ(2) = 15.574, P = 0.000). The median overall survival time of short-term recurrence and not short-term recurrence were 10 months and 62 months, respectively (χ(2) = 45.013, P = 0.000). The median survival time from recurrence to death were 6 months and 14 months, respectively (χ(2) = 40.581, P = 0.000). Multiple-factor analysis suggested that non-solitary HCC and histological low differentiation are independent risk factors which influence short-term recurrence of HCC patients. CONCLUSION: The increase of preoperative serum AFP level suggests the potency of HCC short-term recurrency.