Sagittal balance parameters measurement on cervical spine MR images based on superpixel segmentation.

Introduction: Magnetic Resonance Imaging (MRI) is essential in diagnosing cervical spondylosis, providing detailed visualization of osseous and soft tissue structures in the cervical spine. However, manual measurements hinder the assessment of cervical spine sagittal balance, leading to time-consuming and error-prone processes. This study presents the Pyramid DBSCAN Simple Linear Iterative Cluster (PDB-SLIC), an automated segmentation algorithm for vertebral bodies in T2-weighted MR images, aiming to streamline sagittal balance assessment for spinal surgeons. Method: PDB-SLIC combines the SLIC superpixel segmentation algorithm with DBSCAN clustering and underwent rigorous testing using an extensive dataset of T2-weighted mid-sagittal MR images from 4,258 patients across ten hospitals in China. The efficacy of PDB-SLIC was compared against other algorithms and networks in terms of superpixel segmentation quality and vertebral body segmentation accuracy. Validation included a comparative analysis of manual and automated measurements of cervical sagittal parameters and scrutiny of PDB-SLIC's measurement stability across diverse hospital settings and MR scanning machines. Result: PDB-SLIC outperforms other algorithms in vertebral body segmentation quality, with high accuracy, recall, and Jaccard index. Minimal error deviation was observed compared to manual measurements, with correlation coefficients exceeding 95%. PDB-SLIC demonstrated commendable performance in processing cervical spine T2-weighted MR images from various hospital settings, MRI machines, and patient demographics. Discussion: The PDB-SLIC algorithm emerges as an accurate, objective, and efficient tool for evaluating cervical spine sagittal balance, providing valuable assistance to spinal surgeons in preoperative assessment, surgical strategy formulation, and prognostic inference. Additionally, it facilitates comprehensive measurement of sagittal balance parameters across diverse patient cohorts, contributing to the establishment of normative standards for cervical spine MR imaging.

Deep learning-based high-accuracy quantitation for lumbar intervertebral disc degeneration from MRI.

To help doctors and patients evaluate lumbar intervertebral disc degeneration (IVDD) accurately and efficiently, we propose a segmentation network and a quantitation method for IVDD from T2MRI. A semantic segmentation network (BianqueNet) composed of three innovative modules achieves high-precision segmentation of IVDD-related regions. A quantitative method is used to calculate the signal intensity and geometric features of IVDD. Manual measurements have excellent agreement with automatic calculations, but the latter have better repeatability and efficiency. We investigate the relationship between IVDD parameters and demographic information (age, gender, position and IVDD grade) in a large population. Considering these parameters present strong correlation with IVDD grade, we establish a quantitative criterion for IVDD. This fully automated quantitation system for IVDD may provide more precise information for clinical practice, clinical trials, and mechanism investigation. It also would increase the number of patients that can be monitored.

Thermally Reduced Graphene Oxide/Carbon Nanotube Composite Films for Thermal Packaging Applications.

Thermally reduced graphene oxide/carbon nanotube (rGO/CNT) composite films were successfully prepared by a high-temperature annealing process. Their microstructure, thermal conductivity and mechanical properties were systematically studied at different annealing temperatures. As the annealing temperature increased, more oxygen-containing functional groups were removed from the composite film, and the percentage of graphene continuously increased. When the annealing temperature increased from 1100 to 1400 °C, the thermal conductivity of the composite film also continuously increased from 673.9 to 1052.1 W m-1 K-1. Additionally, the Young's modulus was reduced by 63.6%, and the tensile strength was increased by 81.7%. In addition, the introduction of carbon nanotubes provided through-plane thermal conduction pathways for the composite films, which was beneficial for the improvement of their through-plane thermal conductivity. Furthermore, CNTs apparently improved the mechanical properties of rGO/CNT composite films. Compared with the rGO film, 1 wt% CNTs reduced the Young's modulus by 93.3% and increased the tensile strength of the rGO/CNT composite film by 60.3%, which could greatly improve its flexibility. Therefore, the rGO/CNT composite films show great potential for application as thermal interface materials (TIMs) due to their high in-plane thermal conductivity and good mechanical properties.

Atomic Layer Deposition of Buffer Layers for the Growth of Vertically Aligned Carbon Nanotube Arrays.

Vertically aligned carbon nanotube arrays (VACNTs) show a great potential for various applications, such as thermal interface materials (TIMs). Besides the thermally oxidized SiO2, atomic layer deposition (ALD) was also used to synthesize oxide buffer layers before the deposition of the catalyst, such as Al2O3, TiO2, and ZnO. The growth of VACNTs was found to be largely dependent on different oxide buffer layers, which generally prevented the diffusion of the catalyst into the substrate. Among them, the thickest and densest VACNTs could be achieved on Al2O3, and carbon nanotubes were mostly triple-walled. Besides, the deposition temperature was critical to the growth of VACNTs on Al2O3, and their growth rate obviously reduced above 650 °C, which might be related to the Ostwald ripening of the catalyst nanoparticles or subsurface diffusion of the catalyst. Furthermore, the VACNTs/graphene composite film was prepared as the thermal interface material. The VACNTs and graphene were proved to be the effective vertical and transverse heat transfer pathways in it, respectively.

Seroprevalence of Cytomegalovirus infection in children aged 0-8 years in Nanjing / 中华实用儿科临床杂志

Objective To investigate the seroprevalence of Cytomegalovirus (CMV) infection and ages of the children in primary for better understanding the status of CMV infection in China with evidence-based medicine.Methods Total 837 children randomly selected from Nanjing Children's Hospital,from Jun.to Sep.in 2011,including 513 boys and 324 girls,aged from 1 day to 8 years,with mean age of 3.6 years old,were recruited.Serum samples were tested for CMV IgM,CMV IgG,and CMV IgG avidity index using commercial enzyme-linked immunosorbent assay kits.Results Of the total serum samples from 837 children,690 cases were CMV IgG positive.The overall seroprevalence of CMV IgG was 82.4％,with 83.2％ (427/513 cases) and 81.2％ (263/324 cases) in boys and girls,respectively.There was no significant difference in the seroprevalence of CMV IgG between boys and girls (x2 =0.584,P =0.445).Of the 92 infants less than 6 months old,86 cases were CMV IgG positive,and the positive rate was 93.5％.The prevalence gradually declined in infants after 7 months old,fell to the lowest level of 66.7％ at age of 9 months,and then constantly maintained around 80.0％ from 1 to 8 years old (x2 =15.4,P ＜ 0.001).CMV IgM in 352 serum samples were tested,and 23 (6.5％) cases were CMV IgM positive.The positive rate peaked in infants at age of 2-3 months (7/12 cases,58.3％),then decreased over the age and none of the children older than 6 years were IgM positive (x2 =5.1,P ＜0.001).Furthermore,the CMV IgG avidity index assay was performed in all 23 cases of IgM positive individuals to estimate the primary CMV infection rate.The results showed low avidity index (＜ 30％) in 13 infants,the primary infection rate was 56.5％ (13/23 cases).Most subjects with primary infection (n =7,53.8％) were younger than 1 year old.Conclusions The current seroprevalence of CMV IgG in children in China was around 80.0％,lower than that in adults,and the primary CMV infection mostly occurred before 3 months of age.

Changes of regulatory T cells and T helper cells in peripheral blood and their roles in the severity evaluation in children with asthma / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the changes of CD4+CD25+Foxp3+ regulatory T cells (Treg) and T helper cells (Th1/Th2) in peripheral blood and their roles in the severity evaluation in children with asthma.</p><p><b>METHODS</b>One hundred and fifty children with asthma were classified into acute attack (94 cases) and remission (56 cases) groups according to their clinical features, and the acute attack children were subdivided into mild asthma (54 cases) and severe asthma (40 cases) groups. Fifty healthy children were enrolled as a control group. The levels of CD4+CD25+Foxp3+ Treg, CD4+IFN-γ+ Th1 and CD4+IL-4+ Th2 in peripheral blood were measured by flow cytometer.</p><p><b>RESULTS</b>The mean levels of CD4+CD25+Foxp3+ Treg and the ratio of Th1/Th2 in asthmatic children were lower than those in the control group (P<0.01). The Treg levels and the ratio of Th1/Th2 in the acute attack group were lower than those in the remission group and in the control group (P<0.01). The Treg levels in the severe asthma group were lower than those in the mild asthma group (P<0.01). There was a remarkably negative correlation between Treg levels and the asthma severity (r=-0.737, P<0.01), and the Th1/Th2 ratio was also negatively correlated with the asthma severity (r=-0.615, P<0.01). The Treg levels were positively correlated with the Th1/Th2 ratio (r=0.856, P<0.01).</p><p><b>CONCLUSIONS</b>The Treg levels decrease remarkably and Th subsets imbalance occurs in children with asthma. This suggests that Treg and Th immunity play important roles in the pathogenesis of asthma. The Treg levels and the ratio of Th1/Th2 in peripheral blood may be useful in the evaluation of severity in children with asthma.</p>

Detection of Ampicillin - Resistant Genes and Studies on the Molecular Mechanisms of Ampicillin - Resistant Haemophilus Influenzae / 实用儿科临床杂志

Objective To study the molecular mechanisms of ampicillin- resistant haemophilius influenzae (Hi)in Nanjing. Methods One hundred and fifty- eight strains of Hi isolated from children were collected to detect bata-lactamase. TEM and ROB bata- lacta-mase genes were detected by polymerase chain reaction (PCR) ,and cloned into T vector for sequencing. Results The rate of ampicillin resistance was 41. 77% in Hi isolated from children in Nanjing,40.51 % was found to be bata-lactamase production. Eighty-nine strain were TEM positives, 1 strain was ROB positive,63 strains bata - lactamase positive ampicillin- resistant Hi were identified. The resistance mechanism of ampicillin resistant Hi was production of bata - lactamase , mainly TEM - type enzyme. Two bata - lactamase negative ampicillin - resistant Hi were identified , predicts the other mechanisms of ampicillin - resistant Hi was occuered yet . One strain of non -TEM - type,and non - ROB - type bata - lactamase - producing Hi was identified. Conclusions Ampicillin - resisitant in Hi isolated from children in this region is challenging. TEM bata - lactamase is the principal mechanism of ampicillin - resistant of Hi.