Multifaceted bioinformatic analysis of m6A-related ferroptosis and its link with gene signatures and tumour-infiltrating immune cells in gliomas.

Whether N6-Methyladenosine (m6A)- and ferroptosis-related genes act on immune responses to regulate glioma progression remains unanswered. Data of glioma and corresponding normal brain tissues were fetched from the TCGA database and GTEx. Differentially expressed genes (DEGs) were identified for GO and KEGG enrichment analyses. The FerrDb database was based to yield ferroptosis-related DEGs. Hub genes were then screened out using the cytoHubba database and validated in clinical samples. Immune cells infiltrating into the glioma tissues were analysed using the CIBERSORT R script. The association of gene signature underlying the m6A-related ferroptosis with tumour-infiltrating immune cells and immune checkpoints in low-grade gliomas was analysed. Of 6298 DEGs enriched in mRNA modifications, 144 were ferroptosis-related; NFE2L2 and METTL16 showed the strongest positive correlation. METTL16 knockdown inhibited the migrative and invasive abilities of glioma cells and induced ferroptosis in vitro. NFE2L2 was enriched in the anti-m6A antibody. Moreover, METTL16 knockdown reduced the mRNA stability and level of NFE2L2 (both p < 0.05). Proportions of CD8+ T lymphocytes, activated mast cells and M2 macrophages differed between low-grade gliomas and normal tissues. METTL16 expression was negatively correlated with CD8+ T lymphocytes, while that of NFE2L2 was positively correlated with M2 macrophages and immune checkpoints in low-grade gliomas. Gene signatures involved in the m6A-related ferroptosis in gliomas were identified via bioinformatic analyses. NFE2L2 interacted with METTL16 to regulate the immune response in low-grade gliomas, and both molecules may be novel therapeutic targets for gliomas.

Value of Molybdenum Target X-Ray and High-Frequency Color Doppler Flow Imaging in Early Diagnosis of Breast Carcinoma: A Comparative Analysis.

Background: Breast carcinoma (BC) threatens the physical and mental health of women worldwide, and early diagnosis is important for improving patient outcomes and ensuring successful treatment. Purpose: This research mainly aims to compare and analyze the value of molybdenum target X-ray and high-frequency color Doppler flow imaging (CDFI) in the early diagnosis of BC. Methods: First, 102 patients with suspected early-stage BC (ESBC) admitted to Henan Provincial People's Hospital were examined by molybdenum target X-ray and CDFI. Based on the pathological findings, the diagnostic efficiency data of the two diagnostic modalities such as positive detection rate (PDR), positive predictive value (PPV), negative predictive value (NPV), sensitivity (SEN), specificity (SPE), and accuracy (ACC), as well as imaging information like masses, microcalcifications (MCs), axillary lymph node (LN) metastases, and blood flow signal or vascular sign abnormalities were analyzed. Results: CDFI contributed to higher PDR, PRV, NPV, SEN, and ACC than molybdenum target X-ray in ESBC diagnosis, but similar SPE. The combined diagnosis of molybdenum target X-ray plus CDFI contributed to even higher PDR, PRV, NPV, SEN, and ACC than molybdenum target X-ray alone and higher ACC than CDFI. Imaging inspection revealed that the number of cases of masses, axillary LN metastases, and abnormalities in blood flow signals or vascular signs detected by CDFI was significantly higher than that by molybdenum target X-ray, while the number of MCs was significantly lower. Conclusion: Molybdenum target X-ray plus CDFI is more effective in the diagnosis of ESBC and plays a complementary role in imaging examination, which can synergistically improve the diagnostic ACC of ESBC and is worthy of clinical promotion.

Simultaneous Minimally Invasive Coronary Artery Bypass Grafting and Lung Resection.

BACKGROUND: The best surgical treatment strategy for coexisting coronary artery disease (CAD) and lung cancer (LC) remains controversial. This study analyzed the safety and efficacy of a simultaneous minimally invasive procedure for patients with CAD and LC. METHODS: Patients who underwent simultaneous minimally invasive off-pump coronary artery bypass grafting and lung resection from January 2016 to December 2021 were retrospectively analyzed. The procedure was performed in the fourth intercostal space through a small left anterolateral minithoracotomy. Harvesting of the left internal mammary artery (LIMA) and sewing of the anastomoses were performed under direct vision. Lung resections were performed with or without the assistance of a thoracoscope. RESULTS: Sixteen patients were included with a mean age of 67.13 ± 10.61 years. Procedural success occurred in all patients with a mean operative time of 366.88 ± 94.48 minutes. All patients received at least one coronary artery bypass LIMA graft. Pneumonectomy, lobectomy, segment resection, and wedge resection were performed in one (6.25%), eight (50%), two (12.5%), and five (31.25%) patients, respectively. There were no perioperative deaths or new myocardial infarctions. Complications included one case of postoperative bleeding, two lung infections, two cases of atelectasis, one case of pleural effusion, and one case of cardiac arrhythmia. All the patients were followed up for 1 to 57 months, cancer recurrence occurred in two patients, and one patient died. The remaining patients showed no evidence of tumor recurrence or myocardial infarction. CONCLUSION: This simultaneous minimally invasive procedure is safe and effective for selected patients with CAD and LC.

Application value of overlap guiding tube (OGT) in assisting overlap esophagojejunostomy during laparoscopic total gastrectomy for gastric/gastroesophageal junction (G/GEJ) tumors.

BACKGROUND: The overlap guiding tube (OGT) method, which was designed by our team to assist in overlap esophagojejunostomy, could potentially provide new perspectives for esophagojejunostomy. The application of the OGT-assisted method was first explored by our team and has not yet been reported. METHODS: This cohort study analyzed the 3 month outcomes of 38 gastric/gastroesophageal junction (G/GEJ) tumor patients who underwent OGT-assisted overlap esophagojejunostomy. RESULTS: There were 27 males and 11 females, aged 40-82 years. All patients underwent surgery successfully. The success rate of inserting anvil fork into esophageal lumen at first attempt was 97.4%. The total operation time, esophagojejunostomy time, volume of intraoperative blood loss, and length of surgical incision were 317.6 ± 51.5 min, 20.8 ± 3.8 min, 50.0 (range 15.0-200.0) ml, and 5.0 (range 4.0-8.0) cm, respectively. No procedures were converted to other laparoscopic anastomosis techniques or open approaches. The time to postoperative initial flatus, liquid diet intake, soft diet intake, and length of postoperative hospital stay were 3.0 (range 1.0-6.0) days, 4.0 (range 2.0-9.0)days, 6.0 (range 3.0-11.0) days, and 8.5 (range 6.0-16.0) days, respectively. Overall, postoperative complications were observed in 8 (21.1%) patients. Among them, one patients developed esophagojejunal anastomotic leakage. After 3 months of follow-up, none of the patients developed anastomotic stenosis or experienced unplanned secondary surgery or perioperative death. CONCLUSIONS: OGT-assisted overlap esophagojejunostomy for patients with G/GEJ tumors is safe and feasible, with good short-term effects. OGT method has a satisfactory success rate of inserting anvil fork into esophageal lumen at first attempt and could prevent from developing esophageal submucosa pseudocanals.

Effect of Microvascular Invasion on the Prognosis in Hepatocellular Carcinoma and Analysis of Related Risk Factors: A Two-Center Study.

Objective: Microvascular invasion is considered to initiate intrahepatic metastasis and postoperative recurrence of hepatocellular carcinoma (HCC). We aimed to analyze the effect of MVI on the prognosis in HCC and identify related risk factors for microvascular invasion (MVI). Methods: The clinical data of 553 HCC patients who underwent liver surgery at Qingdao University from January 2014 to December 2018 and 89 patients at Beijing Tsinghua Changgung Hospital treated between October 2014 and October 2019 were collected retrospectively. We explored the impact of MVI on the prognosis of patients with HCC using Kaplan-Meier analysis. We conducted logistic regression analysis to identify variables significantly related to MVI. Results: Pathological examination confirmed the presence of MVI in 265 patients (41.3%). Six factors independently correlated with MVI were incorporated into the multivariate logistic regression analysis: Edmondson-Steiner grade [odds ratio (OR) = 3.244, 95%CI: 2.243-4.692; p < 0.001], liver capsule invasion (OR = 1.755; 95%CI: 1.215-2.535; p = 0.003), bile duct tumor thrombi (OR = 20.926; 95%CI: 2.552-171.553; p = 0.005), α-fetoprotein (> 400 vs. < 400 ng/ml; OR = 1.530; 95%CI: 1.017-2.303; p = 0.041), tumor size (OR = 1.095; 95%CI: 1.027-1.166; p = 0.005), and neutrophil-lymphocyte ratio (OR = 1.086; 95%CI: 1.016-1.162; p = 0.015). The area under the receiver operating characteristic curve (AUC) was 0.743 (95%CI: 0.704-0.781; p < 0.001), indicating that our logistic regression model had significant clinical usefulness. Conclusions: We analyzed the effect of MVI on the prognosis in HCC and evaluated the risk factors for MVI, which could be helpful in making decisions regarding patients with a high risk of recurrence.

Effect of Different Bone Grafting Materials and Mesenchymal Stem Cells on Bone Regeneration: A Micro-Computed Tomography and Histomorphometric Study in a Rabbit Calvarial Defect Model.

This study evaluated the new bone formation potential of micro-macro biphasic calcium phosphate (MBCP) and Bio-Oss grafting materials with and without dental pulp-derived mesenchymal stem cells (DPSCs) and bone marrow-derived mesenchymal stem cells (BMSCs) in a rabbit calvarial bone defect model. The surface structure of the grafting materials was evaluated using a scanning electron microscope (SEM). The multipotent differentiation characteristics of the DPSCs and BMSCs were assessed. Four circular bone defects were created in the calvarium of 24 rabbits and randomly allocated to eight experimental groups: empty control, MBCP, MBCP+DPSCs, MBCP+BMSCs, Bio-Oss+DPSCs, Bio-Oss+BMSCs, and autogenous bone. A three-dimensional analysis of the new bone formation was performed using micro-computed tomography (micro-CT) and a histological study after 2, 4, and 8 weeks of healing. Homogenously porous structures were observed in both grafting materials. The BMSCs revealed higher osteogenic differentiation capacities, whereas the DPSCs exhibited higher colony-forming units. The micro-CT and histological analysis findings for the new bone formation were consistent. In general, the empty control showed the lowest bone regeneration capacity throughout the experimental period. By contrast, the percentage of new bone formation was the highest in the autogenous bone group after 2 (39.4% ± 4.7%) and 4 weeks (49.7% ± 1.5%) of healing (p < 0.05). MBCP and Bio-Oss could provide osteoconductive support and prevent the collapse of the defect space for new bone formation. In addition, more osteoblastic cells lining the surface of the newly formed bone and bone grafting materials were observed after incorporating the DPSCs and BMSCs. After 8 weeks of healing, the autogenous bone group (54.9% ± 6.1%) showed a higher percentage of new bone formation than the empty control (35.3% ± 0.5%), MBCP (38.3% ± 6.0%), MBCP+DPSC (39.8% ± 5.7%), Bio-Oss (41.3% ± 3.5%), and Bio-Oss+DPSC (42.1% ± 2.7%) groups. Nevertheless, the percentage of new bone formation did not significantly differ between the MBCP+BMSC (47.2% ± 8.3%) and Bio-Oss+BMSC (51.2% ± 9.9%) groups and the autogenous bone group. Our study results demonstrated that autogenous bone is the gold standard. Both the DPSCs and BMSCs enhanced the osteoconductive capacities of MBCP and Bio-Oss. In addition, the efficiency of the BMSCs combined with MBCP and Bio-Oss was comparable to that of the autogenous bone after 8 weeks of healing. These findings provide effective strategies for the improvement of biomaterials and MSC-based bone tissue regeneration.

Clinical Statistical Analysis with Comparison between Pelvic and Non-pelvic Chondrosarcoma.

OBJECTIVES: Chondrosarcomas are rare tumors with a variable biological characteristic. Their treatment clinically and surgically is controversial. Analysis of the clinical statistics and prognostic factors of pelvic chondrosarcoma provides a reference for clinical diagnosis and treatment. METHODS: A total of 73 cases of chondrosarcoma were collected, including 24 pelvic samples, from 2008 to 2017 from the hospital database and divided into two groups: pelvic chondrosarcoma and non-pelvic chondrosarcoma. The clinical characteristics and prognostic factors of pelvic chondrosarcoma were analyzed using different statistical methods. RESULTS: Among the 24 pelvic chondrosarcoma patients, the ratio of male to female was 1.4:1, and the median age was 43.5 years. According to the classification proposed by Enneking, there were five grade I, 14 grade II, and five grade III. Histological grading of chondrosarcoma was grade I in one case, II in 15 cases, and III in eight cases. The histological type was 17 conventional, three dedifferentiated, two secondary, one myxoid, and one mesenchymal. The overall survival rates for 24 cases at three, five, and 10 years were 82.2±8.1%, 77.3±8.9%, and 52.4±12.1%, respectively. The local recurrence rate of pelvic chondrosarcoma after surgical resection (83.3%) was significantly higher than that of other sites (34.7%), and the difference was statistically significant (p < 0.001). The final proportion of amputation rate (50.0%) was also higher than other parts (20.4%), with a statistically significant difference (p = 0.010). The total survival of the two groups was not significantly different (p = 0.216). CONCLUSIONS: Chondrosarcoma of bone generally has an excellent prognosis when optimally diagnosed and treated by an experienced team of specialists. Pelvic chondrosarcoma has a higher local recurrence rate than the other sites and tends to result in amputation. Early local recurrence after surgery indicates a poor prognosis.

Comparison of chondrosarcoma cases: current clinical situations among institutions.

OBJECTIVE: Chondrosarcoma is a rare tumor that has a variable biological characteristic, and its treatment is controversial. We performed a comparison review of different regional institutions series to assess the clinical outcome of patients. METHODS: A retrospective review of 33 chondrosarcomas (Grades I, II, and III) patient data since 2013, compared with 15 author's total 868 patients published literature results to find more about clinical and statistical advantages and similarities with author institute cases. Here is the mentioning of clinical information, surgery type categorized, adjuvants types, genders, follow-up years, recurrence, affected areas, death rates, successful outcome, and survival rates using statistical methods. RESULTS: The overall survival rate was 94%, successful outcome 85% in 4.3±1.2 years follow-up. Observed wide resection, distilled water as adjuvant, chemo and radiotherapy significantly shows excellent results over our compared chondrosarcoma literature data. We have also marked that females and humerus bone are more affected by chondrosarcoma among those literature data. CONCLUSIONS: Low-grade chondrosarcoma of the skeleton can be treated with wide resection. Using distilled water give good oncological outcome and a very low rate of post-surgical complications for chondrosarcoma all grades recurrence.

Non-small cell lung cancer with gastric metastasis and repeated gastrointestinal bleeding: A rare case report and literature review.

The occurrence of gastrointestinal metastasis from lung carcinoma is rare. Compared with non-small cell lung cancer (NSCLC), small cell lung cancer more commonly results in this sort of metastasis. Here, we report an unusual case of NSCLC initially without evidence of distant metastasis that developed into gastric metastasis five months after the initial diagnosis, despite the primary lung cancer having a partial response to radiotherapy and chemotherapy. Serial radiological examinations and endoscopic biopsies of the gastric tumor confirmed that it was a metastatic carcinoma originating from the lung. The patient received a total gastrectomy for gastric metastasis due to repeated gastrointestinal bleeding.

[Reduction of Soil Cadmium Activity and Rice Cadmium Content by 4-year-consecutive Application of Organic Fertilizer].

Because commercial organic fertilizers may contain cadmium (Cd) and may cause the dual effect of "inhibition" and "activation" on Cd availability in paddy soil with organic fertilizer input, the reduction of rice Cd following organic fertilizer application is still uncertain. Herewith, typical purple mud paddy fields were selected in the eastern Hunan Province. The effect of commercial organic fertilizer input on Cd reduction of double-rice paddy ecosystem was monitored for four consecutive years. The relationships between brown rice Cd content, soil available Cd, and soil factors (pH, soil labile organic carbon fractions, and iron oxide) at different growth stages in double-rice paddy fields were investigated. Results showed that the input of organic fertilizer reduced the Cd content in brown rice by 28%-56%. Meanwhile, the decrease of Cd content in brown rice of late rice (43%-56%) was higher than that of early rice (28%-45%), and the inter-annual fluctuation of the decrease was relatively small. On the one hand, soil available Cd content decreased by 6%-7% during several growth stages of double-rice (from tillering peak stage to full heading stage) with organic fertilizer input. Additionally, the content of soil exchangeable Cd was decreased by 11%, whereas the content of organic bound Cd was increased by 14%. This directly reflects the decrease of soil Cd availability. On the other hand, the soil pH value was steadily increased by 0.1-0.3 units following organic fertilizer input, which promoted the development of soil from acidity to slight acidity. Besides, the content of soil active organic carbon (light fraction organic carbon, coarse particulate organic carbon, and fine particulate organic carbon) was increased significantly (53%, 77%, and 107%, respectively). This indirectly reflects the decrease in soil Cd availability. This study implies that the decrease of soil Cd availability may be the primary driving force for the reduction of rice Cd content with consecutive organic fertilizer input in purple mud paddy fields.

The medical application of terahertz technology in non-invasive detection of cells and tissues: opportunities and challenges.

Terahertz (THz = 1012 Hz) spectroscopy has shown great potential in biomedical research due to its unique features, such as the non-invasive and label-free identification of living cells and medical imaging. In this review, we summarized the advantages and progresses achieved in THz spectroscopy technology for blood cell detection, cancer cell characterization, bacterial identification and biological tissue discrimination, further introducing THz imaging systems and its progress in tissue imaging. We also highlighted the biological effects of THz radiation during its biological applications and the existing challenges and strategies to accelerate future clinical applications. The future prospects for THz spectroscopy will focus on developing rapid, label-free, and convenient biosensors for point-of-care tests and THz in vivo imaging.

Supercritical Fluid-Assisted Porous Microspheres for Efficient Delivery of Insulin and Inhalation Therapy of Diabetes.

Pulmonary delivery of drugs has attracted increasing attention in healthcare, as the lungs are an easily accessible site for noninvasive systemic delivery of drugs. Although pulmonary inhalation of porous microparticles has been shown to sustain drug delivery, there are limited reports on efficient delivery of insulin and inhalation therapy of diabetes based on supercritical carbon dioxide (SC-CO2 ) technology. Herein, this study reports the fabrication of insulin-loaded poly-l-lactide porous microspheres (INS-PLLA PMs) by using the SC-CO2 technology, and their use as an inhalation delivery system potentially for diabetes therapy. Biocompatibility and delivery efficiency of the PLLA PMs in the lungs are investigated. The PLLA PMs show negligible toxicity to lung-derived cells, resulting in no significant reduction in cell viability, as well as levels of various inflammatory mediators such as interleukin (IL)-6, IL-8, and tumor necrosis factor-α, compared with the negative control group. INS-PLLA PMs are further efficiently deposited in the trachea and the bronchi of superior lobes of the lungs, which exhibit pronounced hypoglycemic activity in induced diabetic rats. Together, the results demonstrate that the INS-PLLA PMs have a strong potential as an effective strategy for inhalation treatment of diabetes.

Comparison of posterolateral fusion and posterior lumbar interbody fusion for treatment of degenerative spondylolisthesis: Analysis of spino-pelvic sagittal balance and postoperative chronic low back pain.

OBJECTIVE: This study aims to compare the spino-pelvic sagittal balance and clinical outcomes of patients treated with posterolateral fusion (PLF) and posterior lumbar interbody fusion (PLIF) for degenerative spondylolisthesis. PATIENTS AND METHODS: A total of 72 patients (28 patients treated with PLF and 44 patients treated with PLIF) were studied. The spino-pelvic sagittal balance, Numerical Rating Scale (NRS), and Oswestry Disability Index (ODI) of the PLF and PLIF groups were compared. The incidence of postoperative chronic low back pain (improvement of NRS less than 50%) in the two groups was also recorded. RESULTS: Significant restoration of spino-pelvic sagittal balance was observed in the PLIF group after surgery. Both groups achieved significant improvements in NRS and ODI postoperatively. Significant differences in postoperative lumbar lordosis and pelvic tilt were found between the PLF and PLIF groups. Significant difference in the incidence of postoperative chronic low back pain was also detected between the two groups. CONCLUSION: PLF and PLIF can improve the clinical outcomes of patients with degenerative spondylolisthesis. PLIF can achieve better restoration of spino-pelvic sagittal balance parameters and less incidence of postoperative chronic low back pain than PLF.

Silencing of Chemosensory Protein Gene NlugCSP8 by RNAi Induces Declining Behavioral Responses of Nilaparvata lugens.

Chemosensory proteins (CSPs) play imperative functions in chemical and biochemical signaling of insects, as they distinguish and transfer ecological chemical indications to a sensory system in order to initiate behavioral responses. The brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacidae), has emerged as the most destructive pest, causing serious damage to rice in extensive areas throughout Asia. Biotic characteristics like monophagy, dual wing forms, and annual long-distance migration imply a critical role of chemoreception in N. lugens. In this study, we cloned the full-length CSP8 gene from N. lugens. Protein sequence analysis indicated that NlugCSP8 shared high sequence resemblance with the CSPs of other insect family members and had the typical four-cysteine signature. Analysis of gene expression indicated that NlugCSP8 mRNA was specifically expressed in the wings of mated 3-day brachypterous females with a 175-fold difference compare to unmated 3-day brachypterous females. The NlugCSP8 mRNA was also highly expressed in the abdomen of unmated 5-day brachypterous males and correlated to the age, gender, adult wing form, and mating status. A competitive ligand-binding assay demonstrated that ligands with long chain carbon atoms, nerolidol, hexanal, and trans-2-hexenal were able to bind to NlugCSP8 in declining order of affinity. By using bioinformatics techniques, three-dimensional protein structure modeling and molecular docking, the binding sites of NlugCSP8 to the volatiles which had high binding affinity were predicted. In addition, behavioral experiments using the compounds displaying the high binding affinity for the NlugCSP8, revealed four compounds able to elicit significant behavioral responses from N. lugens. The in vivo functions of NlugCSP8 were further confirmed through the testing of RNAi and post-RNAi behavioral experiments. The results revealed that reduction in NlugCSP8 transcript abundance caused a decrease in behavioral response to representative attractants. An enhanced understanding of the NlugCSP8 is expected to contribute in the improvement of more effective and eco-friendly control strategies of BPH.

[Expression and clinical significance of proline-rich tyrosine kinase 2 and phospho-protein kinase B in tongue squamous cell carcinoma].

OBJECTIVE: This study aimed to investigate the expression and clinical significance of proline-rich tyrosine kinase 2 (Pyk2) and phospho-protein kinase B (p-AKT) in tongue squamous cell carcinoma (TSCC) and adjacent nontumor tissues. METHODS: The Pyk2 and p-AKT protein levels were detected via immunohistochemistry in 45 cases of TSCC tissues and 30 cases of adjacent nontumor tissues. The relationships of the two protein levels and clinicopathological characteristics were also analyzed. RESULTS: Pyk2 and p-AKT levels were significantly higher in the TSCC tissues than in the adjacent nontumor tissues (P<0.05). Nontumor tissues showed poor or no expression. The expression levels of the two proteins were positively correlated (γs=0.412). The expression of Pyk2 was associated with histopathological differentiation type, regional lymph node metastasis, and TNM staging (P<0.05), but not with age and gender. The expression of p-AKT was only related to histopathological differentiation types (P<0.05). CONCLUSIONS: The abnormal expression of Pyk2 and p-AKT proteins might be closely related to the development and progression of TSCC. Joint detection can be used as an indicator to estimate the degree of TSCC.

Exploring transfer learning for gastrointestinal bleeding detection on small-size imbalanced endoscopy images.

The success of Convolutional Neural Network (CNN) is attributed to their ability to learn rich midlevel image representations as opposed to hand-crafted low-level features used in many natural image classification methods. Learning CNN, however, amounts to estimating millions of parameters and requires a very large number of annotated image samples. In this paper, we explored transfer learning for gastrointestinal bleeding detection on small-size imbalanced endoscopy images, and showed how image representations learned with CNN on large-scale annotated datasets can be efficiently transferred to other tasks with limited amount of training data. We first transferred pre-trained Inception V3 model trained on the ImageNet dataset to compute mid-level image representation, and then fine-tuned the trained model with labeled endoscopy images, and resumed training from already learned weights. Additionally, we introduce both data augmentation and image resampling to increase the size of the training database and the positive sample rate to perform the Transfer Learning. Our results showed that our transfer learning method produces the best performance on AUC (the area under the receiver operating curve), Precision, Recall and Accuracy as compared to both the hand-crafted feature based method and training CNN model from-scratch method.

Robust tracking of dexterous continuum robots: Fusing FBG shape sensing and stereo vision.

Robust and efficient tracking of continuum robots is important for improving patient safety during space-confined minimally invasive surgery, however, it has been a particularly challenging task for researchers. In this paper, we present a novel tracking scheme by fusing fiber Bragg grating (FBG) shape sensing and stereo vision to estimate the position of continuum robots. Previous visual tracking easily suffers from the lack of robustness and leads to failure, while the FBG shape sensor can only reconstruct the local shape with integral cumulative error. The proposed fusion is anticipated to compensate for their shortcomings and improve the tracking accuracy. To verify its effectiveness, the robots' centerline is recognized by morphology operation and reconstructed by stereo matching algorithm. The shape obtained by FBG sensor is transformed into distal tip position with respect to the camera coordinate system through previously calibrated registration matrices. An experimental platform was set up and repeated tracking experiments were carried out. The accuracy estimated by averaging the absolute positioning errors between shape sensing and stereo vision is 0.67±0.65 mm, 0.41±0.25 mm, 0.72±0.43 mm for x, y and z, respectively. Results indicate that the proposed fusion is feasible and can be used for closed-loop control of continuum robots.

CHN2 Promoter Methylation Change May Be Associated With Methamphetamine Dependence.

BACKGROUND: Methamphetamine (MA) abuse is becoming increasingly serious in China. The mechanism of MA dependence remains unclear. CHN2 gene encodes chimeric protein-2 that regulate axonal pruning via the Rac-GTPase system and play a pivotal role in the formation of nervous circuits. Genetic studies suggest that the polymorphism of the CHN2 gene was related to substance dependence. AIMS: The aim of this study was to investigate the association between the methylation of CHN2 gene promoter with MA dependence. METHODS: According to SCID-I (Structured Clinical Interview for DSM-IV Axis I Disorders, SCID-I) used for investigating MA dependence, 224 male MA addicts were recruited into the case group. In addition, 109 healthy men were recruited into the control group. Blood samples were collected with the purpose of detecting the methylation levels of CHN2 gene promoter by methylight qPCR. The association between the methylation of CHN2 gene promoter with MA dependence was analyzed. RESULTS: The mean (sd) methylation levels of CHN2 gene promoter in the case group were significantly higher than in the control group, which were 2795.55 (733.19) and 1026.73 (698.73), respectively, showing significant differences between the two groups (t=21.25, p<0.001). Pearson analysis showed no significant correlation between the methylation levels of CHN2 promoter and other factors (the age of initial MA use, the duration of MA use, combination with K powder, tobacco and alcohol). CONCLUSIONS: The abnormal methylation of CHN2 gene promoter was significantly correlated with MA dependence.

NCoR negatively regulates adipogenic differentiation of mesenchymal stem cells.

The nuclear receptor corepressor (NCoR) regulates the activities of gene transcription. Mesenchymal stem cells (MSCs) derived from bone marrow are multipotent cells which can differentiate into osteoblasts and adipocytes. This study was conducted to investigate the effects of NCoR on adipogenic differentiation of MSCs isolated from the rats. The results suggested that rat MSCs could differentiate into adipocytes successfully after cultured in adipogenic medium. NCoR protein determined by Western blot showed a lower expression in MSC-derived adipocytes, indicating that NCoR was involved in adipocyte differentiation of rat MSCs. It further proved that small interfering RNA (siRNA)-mediated knockdown of NCoR could promote cell viability and differentiation and enhance messenger RNA (mRNA) expression of lipoprotein lipase (LPL) and protein expression of CCAAT/enhancer binding protein-α (C/EBPα) and peroxisome proliferator-activated receptor-γ (PPARγ). However, over-expression of NCoR exerted its functions in contrary to NCoR knockdown. It indicated that NCoR could negatively regulate adipogenic differentiation of rat MSCs.