Deep learning prediction model for central lymph node metastasis in papillary thyroid microcarcinoma based on cytology.

Controversy exists regarding whether patients with low-risk papillary thyroid microcarcinoma (PTMC) should undergo surgery or active surveillance; the inaccuracy of the preoperative clinical lymph node status assessment is one of the primary factors contributing to the controversy. It is imperative to accurately predict the lymph node status of PTMC before surgery. We selected 208 preoperative fine-needle aspiration (FNA) liquid-based preparations of PTMC as our research objects; all of these instances underwent lymph node dissection and, aside from lymph node status, were consistent with low-risk PTMC. We separated them into two groups according to whether the postoperative pathology showed central lymph node metastases. The deep learning model was expected to predict, based on the preoperative thyroid FNA liquid-based preparation, whether PTMC was accompanied by central lymph node metastases. Our deep learning model attained a sensitivity, specificity, positive prediction value (PPV), negative prediction value (NPV), and accuracy of 78.9% (15/19), 73.9% (17/23), 71.4% (15/21), 81.0% (17/21), and 76.2% (32/42), respectively. The area under the receiver operating characteristic curve (value was 0.8503. The predictive performance of the deep learning model was superior to that of the traditional clinical evaluation, and further analysis revealed the cell morphologies that played key roles in model prediction. Our study suggests that the deep learning model based on preoperative thyroid FNA liquid-based preparation is a reliable strategy for predicting central lymph node metastases in thyroid micropapillary carcinoma, and its performance surpasses that of traditional clinical examination.

Proteomics profiling for the global and acetylated proteins of papillary thyroid cancers.

BACKGROUND: Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy cancer among the malignancies of thyroid. Despite of wide usages of proteomics in PTC, the profile of acetylated proteins in PTC remains unsettled, which is helpful for understanding the carcinogenesis mechanism and identifying useful biomarkers for PTC. METHODS: The surgically removed specimens of cancer tissues (Ca-T) and adjacent normal tissues (Ca-N) from 10 female patients pathological diagnosed as PTC (TNM stage III) were enrolled in the study. After preparing the pooled extracts of the whole proteins and the acetylated proteins from 10 cases, TMT labeling and LC/MS/MS methods were applied to the assays of global proteomics and acetylated proteomics separately. Bioinformatics analysis, including KEGG, gene ontology (GO) and hierarchical clustering were performed. Some differentially expressed proteins (DEPs) and differentially expressed acetylated proteins (DEAPs) were validated by individual Western blots. RESULTS: Controlled with the normal tissues adjacent to the lesions, 147 out of 1923 identified proteins in tumor tissues were considered as DEPs in global proteomics, including 78 up-regulated and 69 down-regulated ones, while 57 out of 311 identified acetylated proteins in tumor tissues were DEAPs in acetylated proteomics, including 32 up-regulated and 25 down-regulated, respectively. The top 3 up- and down-regulated DEPs were fibronectin 1, KRT1B protein and chitinase-3-like protein 1, as well as keratin, type I cytoskeletal 16, A-gamma globin Osilo variant and Huntingtin interacting protein-1. The top 3 up- and down-regulated DEAPs were ribosomal protein L18a-like protein, alpha-1-acid glycoprotein 2 and eukaryotic peptide chain release factor GTP-binding subunit ERF3A, as well as trefoil factor 3, thyroglobulin and histone H2B. Functional GO annotation and KEGG pathway analysis based on the DEPs and DEAPs showed completely different changing pictures. Contrary to the top 10 up- and -down regulated DEPs, most of which were addressed in PTC and other types of carcinomas, changes of the majority DEAPs were not mentioned in the literatures. CONCLUSIONS: Taken the profiling of the global and acetylated proteomics together will provide more broad view of protein alterations on the carcinogenesis and new direction for selecting biomarker for diagnosis of PTC.

Pathologic complete response after neoadjuvant v-Raf murine sarcoma viral oncogene homolog B (BRAF) inhibition combined with immunotherapy therapy for anaplastic thyroid carcinoma: a case report and literature review.

Anaplastic thyroid carcinoma (ATC) is a highly malignant tumor with invasive nature. Most patients present with locally advanced and/or distant metastatic diseases that are difficult to treat. We report a case of a previously inoperable patient with v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutated ATC. After a trial of neoadjuvant Dabrafenib/Trametinib with immunotherapy, the tumor became operable, and surgical pathology indicated a pathologic complete response (pCR). We also reviewed cases from the literature that utilized neoadjuvant BRAF-directed therapy in ATCs. These cases emphasize that BRAF-and immune-directed therapy is a feasible option in patients with inoperable ATC and may lead to improved outcomes.

Improvement of low anterior resection syndrome beyond 2 years after total mesorectal excision.

AIM: Bowel dysfunction after sphincter-preserving proctectomy, also known as low anterior resection syndrome (LARS), has significant impact on survivors of rectal cancer. This study aimed to assess the temporal change of LARS beyond 2 years after proctectomy, which has not been fully studied. METHODS: We longitudinally enrolled consecutive patients who had received total mesorectal excision in a tertiary academic medical center, with preoperative neoadjuvant therapy if indicated. LARS score was longitudinally assessed by two serial follow-ups, with a fixed interval of 18 months. RESULTS: Overall, 107 patients responded for the first follow-up after a median of q20 months, 96 of whom responded for the second follow-up after a median of 38 months. At the first follow-up, 48 patients (44.9%) reported major LARS, compared with 23 (24.0%) at the second follow-up (p < 0.001). Mean LARS score improved from 27.3 to 18.6, mostly from "urgency" (12.2 vs. 6.2, p < 0.001) and "clustering of stools" (9.7 vs. 7.7, p = 0.001). Anastomosis less than 3 cm from the anal verge was independently associated with LARS improvement. CONCLUSION: Bowel dysfunction continues to improve 2 years after total mesorectal excision, with most symptom relief in urgency and stool clustering, especially in patients with lower anastomosis.

HDAC1-mediated repression of the retinoic acid-responsive gene ripply3 promotes second heart field development.

Coordinated transcriptional and epigenetic mechanisms that direct development of the later differentiating second heart field (SHF) progenitors remain largely unknown. Here, we show that a novel zebrafish histone deacetylase 1 (hdac1) mutant allele cardiac really gone (crg) has a deficit of ventricular cardiomyocytes (VCs) and smooth muscle within the outflow tract (OFT) due to both cell and non-cell autonomous loss in SHF progenitor proliferation. Cyp26-deficient embryos, which have increased retinoic acid (RA) levels, have similar defects in SHF-derived OFT development. We found that nkx2.5+ progenitors from Hdac1 and Cyp26-deficient embryos have ectopic expression of ripply3, a transcriptional co-repressor of T-box transcription factors that is normally restricted to the posterior pharyngeal endoderm. Furthermore, the ripply3 expression domain is expanded anteriorly into the posterior nkx2.5+ progenitor domain in crg mutants. Importantly, excess ripply3 is sufficient to repress VC development, while genetic depletion of Ripply3 and Tbx1 in crg mutants can partially restore VC number. We find that the epigenetic signature at RA response elements (RAREs) that can associate with Hdac1 and RA receptors (RARs) becomes indicative of transcriptional activation in crg mutants. Our study highlights that transcriptional repression via the epigenetic regulator Hdac1 facilitates OFT development through directly preventing expression of the RA-responsive gene ripply3 within SHF progenitors.

Video mediastinoscopy-assisted superior mediastinal dissection in the treatment of thyroid carcinoma with mediastinal lymphadenopathy: preliminary results.

BACKGROUND: Mediastinal lymph node metastases (MLNM) are not rare in thyroid cancer, but their treatment has not been extensively studied. This study aimed to explore the preliminary application of video mediastinoscopy-assisted superior mediastinal dissection in the diagnosis and treatment of thyroid carcinoma with mediastinal lymphadenopathy. MATERIALS AND METHODS: We retrospectively reviewed the clinical pathologic data and short-term outcomes of thyroid cancer patients with suspicious MLNM treated with video mediastinoscopy-assisted mediastinal dissection at our institution from 2017 to 2020. RESULTS: Nineteen patients were included: 14 with medullary thyroid carcinoma and five with papillary thyroid carcinoma. Superior mediastinal nodes were positive in nine (64.3%) patients with medullary thyroid carcinoma and in four (80.0%) patients with papillary carcinoma. No fatal bleeding occurred. There were three cases of temporary recurrent laryngeal nerve (RLN) palsy postoperatively, one of which was bilateral. Four patients had temporary hypocalcemia requiring supplementation, one had a chyle fistula, and one developed wound infection after the procedure. Postoperative serum molecular markers decreased in all patients. One patient died of cancer while the other 18 patients remained disease-free, with a median follow-up of 33 months. CONCLUSION: Video mediastinoscopy-assisted superior mediastinal dissection can be performed relatively safely in patients with suspicious MLNM. This diagnostic and therapeutic approach may help control locoregional recurrences.

[A Real-time Reconstruction Method of CBCT Short Scan Based on Attenuation Compensation].

Aiming at the problem of timeliness of CBCT reconstruction, a CBCT fast short scan reconstruction method is proposed. At the same time, the image reconstruction process in which a new attenuation compensation algorithm is applied to improve image quality. When performing FDK three-dimensional reconstruction of a single-frame acquisition image, the Parker-weighted image is calculated in real time, and a new attenuation compensation algorithm is applied in the back projection process to complete the short scan Parker-weighted reconstruction. This method simulates the CBCT synchronous acquisition and reconstruction process by establishing collection and reconstruction threads. Under the premise of satisfying the reconstruction quality, the reconstruction can be completed within 1 to 2 seconds after the patient collection is completed, which achieves the purpose of real-time.

The cis-regulatory logic underlying abdominal Hox-mediated repression versus activation of regulatory elements in Drosophila.

During development diverse transcription factor inputs are integrated by cis-regulatory modules (CRMs) to yield cell-specific gene expression. Defining how CRMs recruit the appropriate combinations of factors to either activate or repress gene expression remains a challenge. In this study, we compare and contrast the ability of two CRMs within the Drosophila embryo to recruit functional Hox transcription factor complexes. The DCRE CRM recruits Ultrabithorax (Ubx) and Abdominal-A (Abd-A) Hox complexes that include the Extradenticle (Exd) and Homothorax (Hth) transcription factors to repress the Distal-less leg selector gene, whereas the RhoA CRM selectively recruits Abd-A/Exd/Hth complexes to activate rhomboid and stimulate Epidermal Growth Factor secretion in sensory cell precursors. By swapping binding sites between these elements, we found that the RhoA Exd/Hth/Hox site configuration that mediates Abd-A specific activation can convey transcriptional repression by both Ubx and Abd-A when placed into the DCRE. We further show that the orientation and spacing of Hox sites relative to additional binding sites within the RhoA and DCRE is critical to mediate cell- and segment-specific output. These results indicate that the configuration of Exd, Hth, and Hox site within RhoA is neither Abd-A specific nor activation specific. Instead Hox specific output is largely dependent upon the presence of appropriately spaced and oriented binding sites for additional TF inputs. Taken together, these studies provide insight into the cis-regulatory logic used to generate cell-specific outputs via recruiting Hox transcription factor complexes.

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC): A report of 2,781 cases in a Chinese population.

OBJECTIVE: To evaluate the diagnostic utility of The Bethesda System for Reporting Thyroid Cytology (TBSRTC) at Peking University Cancer Hospital, the incidence of noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP), and the impact of reclassification on cytopathological outcomes. METHODS: We performed a retrospective study of thyroid fine-needle aspiration (FNA) cases between April 2014 and March 2019. The FNA results were classified according to TBSRTC. Post-surgery histological findings were followed up. RESULTS: A total of 2,781 thyroid FNAs were performed. The incidences of the 6 diagnostic categories (DCs I-VI) were 14.8%, 17.1%, 15.8%, 2.3%, 11.6% and 38.5%, respectively. A total of 1,122 patients (40.3%) had corresponding histological results. NIFTP accounted for 0.4% of papillary thyroid carcinoma (PTC) cases, and there was no significant difference in the risk of malignancy (ROM) for each TBSRTC DC between "NIFTP=carcinoma (Ca)" and "NIFTP≠Ca". When "NIFTP=Ca", the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of TBSRTC were 98.0%, 84.0%, 99.4%, 58.3%, and 97.5%, respectively. When "NIFTP≠Ca", the sensitivity, specificity, PPV, NPV and accuracy of the TBSRTC were 98.1%, 81.5%, 99.3%, 61.1%, and 97.5%, respectively. CONCLUSIONS: TBSRTC is effective in the preoperative diagnosis of thyroid nodules in Peking University Cancer Hospital. The impact of the reclassification of NIFTP on cytopathological outcomes is limited because of its low incidence, and the revised ROMs are not suitable for Asian patients.

Nr2f1a balances atrial chamber and atrioventricular canal size via BMP signaling-independent and -dependent mechanisms.

Determination of appropriate chamber size is critical for normal vertebrate heart development. Although Nr2f transcription factors promote atrial maintenance and differentiation, how they determine atrial size remains unclear. Here, we demonstrate that zebrafish Nr2f1a is expressed in differentiating atrial cardiomyocytes. Zebrafish nr2f1a mutants have smaller atria due to a specific reduction in atrial cardiomyocyte (AC) number, suggesting it has similar requirements to Nr2f2 in mammals. Furthermore, the smaller atria in nr2f1a mutants are derived from distinct mechanisms that perturb AC differentiation at the chamber poles. At the venous pole, Nr2f1a enhances the rate of AC differentiation. Nr2f1a also establishes the atrial-atrioventricular canal (AVC) border through promoting the differentiation of mature ACs. Without Nr2f1a, AVC markers are expanded into the atrium, resulting in enlarged endocardial cushions (ECs). Inhibition of Bmp signaling can restore EC development, but not AC number, suggesting that Nr2f1a concomitantly coordinates atrial and AVC size through both Bmp-dependent and independent mechanisms. These findings provide insight into conserved functions of Nr2f proteins and the etiology of atrioventricular septal defects (AVSDs) associated with NR2F2 mutations in humans.

The regulatory repertoire of PLZF and SALL4 in undifferentiated spermatogonia.

Spermatogonial stem cells (SSCs) maintain spermatogenesis throughout adulthood through balanced self-renewal and differentiation, yet the regulatory logic of these fate decisions is poorly understood. The transcription factors Sal-like 4 (SALL4) and promyelocytic leukemia zinc finger (PLZF; also known as ZBTB16) are known to be required for normal SSC function, but their targets are largely unknown. ChIP-seq in mouse THY1(+) spermatogonia identified 4176 PLZF-bound and 2696 SALL4-bound genes, including 1149 and 515 that were unique to each factor, respectively, and 1295 that were bound by both factors. PLZF and SALL4 preferentially bound gene promoters and introns, respectively. Motif analyses identified putative PLZF and SALL4 binding sequences, but rarely both at shared sites, indicating significant non-autonomous binding in any given cell. Indeed, the majority of PLZF/SALL4 shared sites contained only PLZF motifs. SALL4 also bound gene introns at sites containing motifs for the differentiation factor DMRT1. Moreover, mRNA levels for both unique and shared target genes involved in both SSC self-renewal and differentiation were suppressed following SALL4 or PLZF knockdown. Together, these data reveal the full profile of PLZF and SALL4 regulatory targets in undifferentiated spermatogonia, including SSCs, which will help elucidate mechanisms controlling the earliest cell fate decisions in spermatogenesis.

A supervised network for fast image-guided radiotherapy (IGRT) registration.

3D/3D image registration in IGRT, which aligns planning Computed Tomography (CT) image set with on board Cone Beam CT (CBCT) image set in a short time with high accuracy, is still a challenge due to its high computational cost and complex anatomical structure of medical image. In order to overcome these difficulties, a new method is proposed which contains a coarse registration and a fine registration. For the coarse registration, a supervised regression convolutional neural networks (CNNs) is used to optimize the spatial variation by minimizing the loss when combine the CT images with the CBCT images. For the fine registration, intensity-based image registration is used to calculate the accurate spatial difference of the input image pairs. A coarse registration can get a rough result with a wide capture range in less than 0.5 s. Sequentially a fine registration can get accurate results in a reasonable short time. RSD-111 T chest phantom was used to test our new method. The set-up error was calculated in less than 10s in time scale, and was reduced to sub-millimeter level in spatial scale. The average residual errors in translation and rotation are within ±0.5 mm and ± 0.2°.

Pretreatment with low-dose gadolinium chloride attenuates myocardial ischemia/reperfusion injury in rats.

AIM: We have shown that low-dose gadolinium chloride (GdCl3) abolishes arachidonic acid (AA)-induced increase of cytoplasmic Ca(2+), which is known to play a crucial role in myocardial ischemia/reperfusion (I/R) injury. The present study sought to determine whether low-dose GdCl3 pretreatment protected rat myocardium against I/R injury in vitro and in vivo. METHODS: Cultured neonatal rat ventricular myocytes (NRVMs) were treated with GdCl3 or nifedipine, followed by exposure to anoxia/reoxygenation (A/R). Cell apoptosis was detected; the levels of related signaling molecules were assessed. SD rats were intravenously injected with GdCl3 or nifedipine. Thirty min after the administration the rats were subjected to LAD coronary artery ligation followed by reperfusion. Infarction size, the release of serum myocardial injury markers and AA were measured; cell apoptosis and related molecules were assessed. RESULTS: In A/R-treated NRVMs, pretreatment with GdCl3 (2.5, 5, 10 µmol/L) dose-dependently inhibited caspase-3 activation, death receptor-related molecules DR5/Fas/FADD/caspase-8 expression, cytochrome c release, AA release and sustained cytoplasmic Ca(2+) increases induced by exogenous AA. In I/R-treated rats, pre-administration of GdCl3 (10 mg/kg) significantly reduced the infarct size, and the serum levels of CK-MB, cardiac troponin-I, LDH and AA. Pre-administration of GdCl3 also significantly decreased the number of apoptotic cells, caspase-3 activity, death receptor-related molecules (DR5/Fas/FADD) expression and cytochrome c release in heart tissues. The positive control drug nifedipine produced comparable cardioprotective effects in vitro and in vivo. CONCLUSION: Pretreatment with low-dose GdCl3 significantly attenuates I/R-induced myocardial apoptosis in rats by suppressing activation of both death receptor and mitochondria-mediated pathways.

Graph neural network based on brain inspired forward-forward mechanism for motor imagery classification in brain-computer interfaces.

Introduction: Within the development of brain-computer interface (BCI) systems, it is crucial to consider the impact of brain network dynamics and neural signal transmission mechanisms on electroencephalogram-based motor imagery (MI-EEG) tasks. However, conventional deep learning (DL) methods cannot reflect the topological relationship among electrodes, thereby hindering the effective decoding of brain activity. Methods: Inspired by the concept of brain neuronal forward-forward (F-F) mechanism, a novel DL framework based on Graph Neural Network combined forward-forward mechanism (F-FGCN) is presented. F-FGCN framework aims to enhance EEG signal decoding performance by applying functional topological relationships and signal propagation mechanism. The fusion process involves converting the multi-channel EEG into a sequence of signals and constructing a network grounded on the Pearson correlation coeffcient, effectively representing the associations between channels. Our model initially pre-trains the Graph Convolutional Network (GCN), and fine-tunes the output layer to obtain the feature vector. Moreover, the F-F model is used for advanced feature extraction and classification. Results and discussion: Achievement of F-FGCN is assessed on the PhysioNet dataset for a four-class categorization, compared with various classical and state-of-the-art models. The learned features of the F-FGCN substantially amplify the performance of downstream classifiers, achieving the highest accuracy of 96.11% and 82.37% at the subject and group levels, respectively. Experimental results affirm the potency of FFGCN in enhancing EEG decoding performance, thus paving the way for BCI applications.

[Analysis of risk factors for congenital auriclar deformity and its different types].

Objective:To Explore the clinical characteristics,risk factors,and differences in risk factors for different types of congenital auricular deformities,in order to provide theoretical basis for precise prevention and control of congenital auriclar deformity. Methods:Full-term newborns born in the Second Affiliated Hospital of Zhengzhou University from May 2022 to January 2023 were screened for auricle malformation, general information and data were collected,,and high-risk factors were investigated withself-made questionnaire.Using a case-control study method,newborns with auriclar deformities were selected as the case group and those without auriclar deformities during the same period were selected as the control group.A case-control study was conducted to analyze the incidence rate,high-risk factors,and differences in high-risk factors for different types of auricle deformities. Results:A total of 1 758 newborns （3 516 ears） were included in this study,including 562 newborns（927 ears） with auriclar deformities,the incidence of congenital malformations of the auricle is 26.37%.Among them,289 ears （8.22%） were helical rim deformity,244 ears （6.94%） were lidding/lop ear,166 ears （4.72%） were mixed deformities,131 ears （3.73%） were prominent/cup ear,79 ears （2.25%） were Stahl's ears,16 ears （0.46%） were abnormal conchal crus,and 2 ears （0.06%） were cryptotia.Maternal history of infection in early pregnancy（OR=1.513，95%CI 1.119-2.045）,previous miscarriage history（OR=1.300，95%CI 1.049-1.613）,and abnormal pregnancy（OR=1.278，95%CI 1.032-1.582） are risk factors for congenital auricular malformations.There was no statistically significant difference in the history of infection（χ²=1.877，P=0.391）,previous miscarriage（χ²=4.706，P=0.095）,and abnormal pregnancy（χ²=5.026，P=0.081） among mothers with helical rim deformity,lidding/lop ear,and mixed deformities. Conclusion:The incidence rate of congenital auricle deformity is high, with common malformations such as helical rim deformity, lidding/lop ear,and mixed deformities. Congenital auricular deformity is caused by various factors, the same risk factor has roughly the same impact on different types of morphological abnormalities.

Combination kinase inhibitors and immunotherapy for unresectable anaplastic thyroid carcinoma: A retrospective single-center study.

INTRODUCTION: Anaplastic thyroid carcinoma (ATC) is rare but has a very poor prognosis. New therapeutic options such as multikinase inhibitors and selective tyrosine kinase inhibitors have revolutionized the treatment of ATC, with immunotherapy also showing encouraging effects. This study evaluated the efficacy and safety of kinase inhibitors combined with an anti-PD-1 inhibitor as first-line treatment, as well as in the neoadjuvant setting for patients with unresectable ATC. MATERIALS & METHODS: This retrospective single-center study recruited consecutive patients with stage IVB and IVC ATC who received first-line kinase inhibitors plus immunotherapy between June 2021 and June 2023. The patients were treated with either selective or multi-kinase inhibitors (dabrafenib/trametinib, lenvatinib, or anlotinib) in combination with one immune checkpoint inhibitor (pembrolizumab, sintilimab, or camrelizumab). The endpoints included overall survival (OS), progression-free survival (PFS), response evaluation, and feasibility of R0/R1 resection. RESULTS: Eighteen patients were included in this analysis. The median OS (mOS) was 14.0 months and the 12-month survival rate was 55.6 %. The mOS in BRAF V600E mutated ATC was not reached, significantly longer than non-BRAF V600E mutated ATC (4.0 months [95 %CI, 1.1-6.9], p = 0.049). Among evaluable patients, 5 achieved a complete response (CR) and 6 patients achieved partial response (PR). The best ORR was 61.1 %. Surgical resection was feasible in 7/18 (38.9 %) patients. One grade 5 adverse event (AE) occurred. Most AEs were well tolerated. CONCLUSIONS: Combination kinase inhibitors with immunotherapy as first-line therapy are safe and effective for the treatment of unresectable ATC, especially with BRAF V600E mutation.

Realization of thousand-second improved confinement plasma with Super I-mode in Tokamak EAST.

Mastering nuclear fusion, which is an abundant, safe, and environmentally competitive energy, is a great challenge for humanity. Tokamak represents one of the most promising paths toward controlled fusion. Obtaining a high-performance, steady-state, and long-pulse plasma regime remains a critical issue. Recently, a big breakthrough in steady-state operation was made on the Experimental Advanced Superconducting Tokamak (EAST). A steady-state plasma with a world-record pulse length of 1056 s was obtained, where the density and the divertor peak heat flux were well controlled, with no core impurity accumulation, and a new high-confinement and self-organizing regime (Super I-mode = I-mode + e-ITB) was discovered and demonstrated. These achievements contribute to the integration of fusion plasma technology and physics, which is essential to operate next-step devices.

Indications of Superselective Neck Dissection in Patients With Lateral Node Metastasis of Papillary Thyroid Carcinoma.

OBJECTIVE: The extent of neck dissection in papillary thyroid carcinoma (PTC) patients with lateral neck metastasis is controversial. This work aims to screen the patients suitable for superselective neck dissections including only levels III-IV. STUDY DESIGN: Prospective observational cohort study. SETTING: The study was conducted in a high-volume tertiary care setting. METHODS: A total of 134 consecutive previously untreated PTC patients with lateral neck metastases and subjected to 154 therapeutic lateral neck dissections (including levels II, III, IV, and VB) between June 2018 and March 2021 were enrolled. Fine-needle aspiration was performed preoperatively at each suspicious neck level. Clinical predictors were analyzed for occult lymph node metastases at levels II and VB. RESULTS: As a result, 44.8% and 5.8% of neck specimens exhibited metastatic lymph nodes at levels II and VB. In addition, univariate and multivariate analyses showed that the primary tumor in the ipsilateral thyroid upper lobe (P = .016, odds ratio = 3.528) and clinically multiple metastatic lymph nodes in level III-IV (P = .005, odds ratio = 6.414) were independent predictive factors for occult level II metastases. All 3 (1.9%) occult metastases at level VB were found in necks with preoperative multiple lymph node metastases. CONCLUSIONS: A superselective lateral neck dissection including levels III to IV may be considered in patients with PTC when the preoperative evaluation identifies a single lymph node metastasis located at levels III to IV and the primary tumor is not in the upper lobe of the ipsilateral thyroid.

Level IIb neck dissection guided by fine-needle aspiration for N1b papillary thyroid carcinoma.

BACKGROUND: The extent of neck dissection for patients with papillary thyroid carcinoma (PTC) metastasis in lateral cervical lymph nodes is still debated. Studies aiming to omit level IIb were generally based on postoperative histopathologic information. The purpose of this study was to evaluate the predictive value of fine-needle aspiration (FNA) for level II lymph nodes in identifying candidates for neck dissection sparing level IIb before surgery. METHODS: We prospectively enrolled 156 consecutive previously untreated PTC patients with lateral neck metastases who were subjected to 178 therapeutic lateral neck dissections (including level IIa, IIb, III, IV, and Vb) between June 2018 and August 2021. Ultrasound-guided FNA of suspicious lymph nodes at level II was preoperatively performed. The cytology of FNA and thyroglobulin (Tg) washout concentration with other clinical predictors was analyzed for lymph node metastases at level IIb. RESULTS: Preoperative ultrasonography revealed suspicious lymph nodes at level II in 118 cases, and fifty were positive on FNA results. Metastasis at level IIb was seen in 17 (9.6%) of the postoperative specimens. By univariate analysis, the rate of level IIb metastasis was significantly higher in patients with FNA-positive lymph nodes at level II (P<0.001, odds ratio = 16.899). The tumor sizes of the two FNA-negative level IIb metastatic lymph nodes were 0.4 mm and 3 mm. CONCLUSIONS: Level IIb lymph node dissection may be omitted in the treatment of N1b PTC patients if FNA to level II lymph nodes is negative.

A Snake-Inspired Layer-Driven Continuum Robot.

Continuum robots with redundant degrees of freedom and postactuated devices are suitable for application in aerospace, nuclear facilities, and other narrow and multiobstacle special environments. The development of a snake-inspired continuum robot is presented in this study. The morphological skeleton structure of the snake body is simulated using underactuated continuum joints, which include several rigid-body joints in series. Each rigid-body joint is driven by the traction of a wire rope. Based on the layered-drive principle, angular synchronous motion can be realized in space with multiple rigid-body joints in a single continuous joint, which can considerably reduce the complexity of the inverse kinematics solution, terminal drive box, and control system. The static and dynamic characteristics of the snake-inspired robot are obtained through torque balance and an equivalent transformation. Finally, we demonstrate trajectory planning and load capacity testing in two robot prototypes with arm lengths of 1500 and 2300 mm (including two and four continuous joints, respectively). The rationality of the structure and the correctness of the control of the layered-drive snake-inspired robot are verified.