A machine learning approach to identify correlates of current e-cigarette use in Canada

Aim: Popularity of electronic cigarettes (i.e. e-cigarettes) is soaring in Canada. Understanding person-level correlates of current e-cigarette use (vaping) is crucial to guide tobacco policy, but prior studies have not fully identified these correlates due to model overfitting caused by multicollinearity. This study addressed this issue by using classification tree, a machine learning algorithm. Methods: This population-based cross-sectional study used the Canadian Tobacco, Alcohol, and Drugs Survey (CTADS) from 2017 that targeted residents aged 15 or older. Forty-six person-level characteristics were first screened in a logistic mixed-effects regression procedure for their strength in predicting vaper type (current vs. former vaper) among people who reported to have ever vaped. A 9:1 ratio was used to randomly split the data into a training set and a validation set. A classification tree model was developed using the cross-validation method on the training set using the selected predictors and assessed on the validation set using sensitivity, specificity and accuracy. Results: Of the 3,059 people with an experience of vaping, the average age was 24.4 years (standard deviation = 11.0), with 41.9% of them being female and 8.5% of them being aboriginal. There were 556 (18.2%) current vapers. The classification tree model performed relatively well and suggested attraction to e-cigarette flavors was the most important correlate of current vaping, followed by young age (< 18) and believing vaping to be less harmful to oneself than cigarette smoking. Conclusions: People who vape due to flavors are associated with very high risk of becoming current vapers. The findings of this study provide evidence that supports the ongoing ban on flavored vaping products in the US and suggests a similar regulatory intervention may be effective in Canada.

Application of radar measurement technology in 3D surveying and mapping of transmission lines

This paper briefly introduces the background, significance, and development status of 3D radar technology at home and abroad, and then explains the concept, working principle, system composition, and workflow of the radar system. Combined with the current development trend of smart grids, it focuses on the application scope of this technology in the field of transmission line construction, operation, and maintenance. Then, through the specific implementation of the project cases, the daily operation and maintenance of four 500 kV transmission lines in Nanjing have played a certain guiding role. Finally, according to the development trend of smart grid and the actual demand of power system production and business integration, this paper briefly prospects the function expansion of this technology in transmission line operation evaluation, fault analysis and diagnosis, emergency rescue plan formulation, and other fields.

P2X4 receptor in the dorsal horn contributes to BDNF/TrkB and AMPA receptor activation in the pathogenesis of remifentanil-induced postoperative hyperalgesia in rats

The mechanism underlying the high incidence of remifentanil-induced postoperative hyperalgesia is unclear. Also, no effective prevention method exists. Inflammatory pain-related studies showed that P2X4 purinergic receptors (P2X4Rs) in the dorsal horn of the spinal cord and dorsal root ganglia are essential for maintaining allodynia caused by inflammation. However, little is known about its role in opioid-induced hyperalgesia. This study aimed to determine the role of P2X4R and related signaling pathways in the remifentanil-induced postoperative hyperalgesia (RIH) model. The study simulated the remifentanil infusion and surgical incision during general anesthesia. The mRNA and protein expression level of P2X4R in rats with RIH model increased from 2 h to 48 h after the surgery. The administration of P2X4R inhibitors prevented the occurrence of RIH, resulting in a reduction in mechanical and thermal pain. Moreover, P2X4R was involved in RIH in male and female rats, indicating no sex-specific difference. P2X4R also increased the expression of AMPA receptor subunit GluA1 in a brain-derived neurotrophic factor (BDNF) / tyrosine receptor kinase B (TrkB) dependent manner. The results from whole-cell patch-clamp recording suggested that P2X4R also regulated AMPA receptor-mediated miniature excitatory postsynaptic currents and participated in the synaptic plasticity of spinal dorsal horn neurons. In summary, P2X4R was involved in AMPAR expression, electrophysiological function, and synaptic plasticity of spinal dorsal horn neurons through BDNF/TrkB signaling. This might be the mechanism underlying RIH, and hence inhibition of P2X4R might be a potential treatment strategy.

Identification of the novel HLA-C*03:04:79 allele in a Chinese bone marrow donor

HLA-C*03:04:79 differs from HLA-C*03:04:01:01 by a single nucleotide substitution at position 834 G>A.

Polysaccharides extracted from balanophora polyandra Griff (BPP) ameliorate renal Fibrosis and EMT via inhibiting the Hedgehog pathway

Renal interstitial fibrosis (RIF) is a crucial pathological change leading to chronic kidney disease (CKD). Currently, no effective medicines have been available for treating it. In our research, we examined the effects of polysaccharides extracted from Balanophora polyandra Griff (BPPs) on kidney fibrosis and epithelial to mesenchymal transition (EMT) in vivo and in vitro, aiming to explore the underlying mechanisms. By using the mice with unilateral urethral obstruction (UUO) as experimental subjects, we examined the medicinal values of BPPs on alleviating RIF. The effects of BPPs were evaluated by examining the histological staining and relative mRNA and protein expression levels of the related genes. The possible underlying mechanisms were further explored with human normal renal proximal tubular epithelia (HK‐2 cells) as in vitro model. In UUO mice, BPP treatment could significantly alleviate interstitial fibrosis through reducing the components (Collagens I, III and IV) of extracellular matrix (ECM), and reducing the activation of fibroblasts producing these components, as revealed by inhibiting the hallmarks (fibronectin and α‐SMA) of fibroblast activation. Furthermore, BPP administration increased the expression levels of matrix metalloproteinases (MMPs) and declined those of tissue inhibitors of metalloproteinases (TIMPs). BPPs markedly ameliorated EMT in both the kidneys of UUO mice and TGF‐β1 treated HK‐2 cells. Moreover, BPP treatment decreased the expression levels of several transcriptional factors involved in regulating E‐cadherin expression, including snail, twist and ZEB1. Additionally, the Hedgehog pathway was found to be closely correlated with renal fibrosis and EMT. Altogether, our results clearly demonstrated that BPP treatment effectively inhibited the Hedgehog pathway both in renal tissues of UUO mice and TGF‐β1‐treated HK‐2 cells. Thus, BPPs ameliorated RIF and EMT in vivo and in vitro via suppressing Hedgehog signalling pathway.

Precise resection of multiple pulmonary nodules using a three-dimensional reconstruction model: A case report

A 48‐year‐old woman presented to our department and chest computed tomography (CT) revealed five pulmonary nodules, two of which were in the left upper lobe of the lung and three in the superior segment of the left lower lobe., All the lesions were resected for comprehensive histological assessment in order to distinguish synchronous multiple primary lung cancers (SMPLCs) from intrapulmonary metastases. The nodules were all successfully removed by minimally invasive surgery under the guidance of three dimensional (3D) reconstruction, in order to preserve as much lung function for the patient as possible. Postoperative histopathological examination demonstrated the presence of SMPLC. The patient was discharged from hospital on postoperative day 4 without any complications.

Dynamic RNA Regulation in the Brain Underlies Physiological Plasticity in a Hibernating Mammal

Hibernation is a physiological and behavioral phenotype that minimizes energy expenditure. Hibernators cycle between profound depression and rapid hyperactivation of multiple physiological processes, challenging our concept of mammalian homeostasis. How the hibernator orchestrates and survives these extremes while maintaining cell to organismal viability is unknown. Here, we enhance the genome integrity and annotation of a model hibernator, the 13-lined ground squirrel. Our new assembly brings this genome to near chromosome-level contiguity and adds thousands of previously unannotated genes. These new genomic resources were used to identify 6,505 hibernation-related, differentially-expressed and processed transcripts using RNA-seq data from three brain regions in animals whose physiological status was precisely defined using body temperature telemetry. A software tool, squirrelBox, was developed to foster further data analyses and visualization. SquirrelBox includes a comprehensive toolset for rapid visualization of gene level and cluster group dynamics, sequence scanning of k-mer and domains, and interactive exploration of gene lists. Using these new tools and data, we deconvolute seasonal from temperature-dependent effects on the brain transcriptome during hibernation for the first time, highlighting the importance of carefully timed samples for studies of differential gene expression in hibernation. The identified genes include a regulatory network of RNA binding proteins that are dynamic in hibernation along with the composition of the RNA pool. In addition to passive effects of temperature, we provide evidence for regulated transcription and RNA turnover during hibernation. Significant alternative splicing, largely temperature dependent, also occurs during hibernation. These findings form a crucial first step and provide a roadmap for future work toward defining novel mechanisms of tissue protection and metabolic depression that may 1 day be applied toward improving human health.

Unpaid Caregiving and Labor Force Participation among Chinese Middle-Aged Adults

Unpaid family caregivers must consider the economic trade-off between caregiving and paid employment. Prior literature has suggested that labor force participation (LFP) declines with caregiving intensity, but no study has evaluated this relationship by accounting for the presence of both kinks and discontinuities. Here we used respondents of the China Health and Retirement Longitudinal Study baseline survey who were nonfarming, of working age (aged 45-60) and had a young grandchild and/or a parent/parent-in-law. For women and men separately, a caregiving threshold-adjusted probit model was used to assess the association between LFP and weekly unpaid caregiving hours. Instrumental variables were used to rule out the endogeneity of caregiving hours. Of the 3718 respondents in the analysis, LFP for men was significantly and inversely associated with caregiving that involved neither discontinuities nor kinks. For women, a kink was identified at the caregiving threshold of eight hrs/w such that before eight hours, each caregiving hour was associated with an increase of 0.0257 in the marginal probability of LFP, but each hour thereafter was associated with a reduction of 0.0014 in the marginal probability of LFP. These results have implications for interventions that simultaneously advance policies of health, social care and labor force.

Silver-catalyzed desulfurizative annulation of 1,2-benzisothiazoles with ynamides to construct multi-substituted isoquinolines

An unprecedented silver-catalyzed desulfurizative annulation of 1,2-benzisothiazoles with ynamides to access multi-substituted isoquinoline derivatives is disclosed.

Relationship of arsenic and chromium availability with carbon functional groups, aluminum and iron in Little Washita River Experimental Watershed Reservoirs, Oklahoma, USA

Sediment from three reservoirs located in the Little Washita River Experimental Watershed (LWREW) in Oklahoma, USA with contrasting dominant land uses were analyzed for total and extractable concentrations of arsenic (As) and chromium (Cr), and the potential ecologic risk to benthic organisms. Extractable As ranged from 0.24 to 1.21 mg kg^-1, in the order grazing>cropland>forest and 0.13-0.58 mg kg^-1 for extractable Cr, in the order of forest>grazing>cropland. However, only approximately < 1.5% of total As and < 4% of total Cr were extractable. Total As ranged from 16.2 to 141 mg kg^-1 and total Cr ranged from 5.06 to 40.1 mg kg^-1 both in the order of cropland>grazing>forest. The sediment exhibited an alkaline pH (8.0-8.7). As sorption exhibited a positive relationship with Al (r = 0.9995; P = 0.0001), Fe (r = 0.9829; P = 0.0001), and C (r = 0.4090; P = 0.0017) and Cr correlated positively with Al (r = 0.9676 P = 0.0001), Fe (r = 0.9818; P = 0.0001), and C (r = 0.3368; P = 0.0111). In addition, both As and Cr exhibited positive relationships with carbon (C) functional groups in the order of O-alkyl C> methoxyl C> alkyl C> aromatic C> carboxyl C> phenolic C. The sediment concentration analysis results illustrated that As in all reservoirs exceeded their respective Threshold Effect Level (TEL) and/or Probable Effect Level (PEL) indicating that existing concentrations of metals in these sediments were sufficiently high to cause adverse effects. However, Cr concentrations in all reservoirs evaluated was lower compared to the TEL and PEL.

Recurrent Extra-gastrointestinal Stromal Tumor of the Vagina: A Case Report and Review of the Literature

Gastrointestinal tumors are uncommonly found outside the gastrointestinal tract, and extremely rare in the vaginal wall. In this case report, a 39-year-old female, she was finally diagnosed with an extra gastrointestinal stromal tumor (EGIST) when she presented with a recurrent vaginal tumor, while misdiagnosed after the first surgery. She had definitive surgical clearance and was taking targeted drug therapy with no sign of recurrence after follow-up for 13 months. Immunohistochemistry and cytogenetic's remain the most definitive method to diagnose EGISTs. Surgical resection and postoperative adjuvant targeted therapy are the optimum treatment options.

Dialysis Initiation and All-Cause Mortality Among Incident Adult Patients With Advanced CKD: A Meta-analysis With Bias Analysis

Rationale & Objectives

Due to unmeasured confounding, observational studies have limitations when assessing whether dialysis initiation reduces mortality compared with conservative therapy among adults with advanced chronic kidney disease (CKD). We addressed this issue in this meta-analysis.

Study Design

Meta-analysis with bias analysis for unmeasured confounding.

Setting & Study Population

Adults with stage 4 or 5 CKD who had initiated dialysis or conservative treatment.

Selection Criteria for Studies

Prospective or retrospective cohort studies comparing survival of dialysis versus conservatively managed patients were searched on MEDLINE and Embase from January 2009 to March 20, 2019.

Data Extraction

HRs of all-cause mortality associated with dialysis initiation compared with conservative treatment.

Analytical Approach

We pooled HRs using a random-effects model. We estimated the percentage of effect sizes more protective than HRs of 0.80 and severity of unmeasured confounding that could reduce this percentage to only 10%. Subgroup analysis was performed for studies with only older patients (aged ≥ 65 years).

Results

12 studies were included that involved 16,609 dialysis patients and 3,691 conservatively managed patients. A random-effects model suggested that dialysis initiation was associated with a mean mortality HR of 0.47 (95% CI, 0.34-0.64), in which 92% (95% CI, 50%-100%) of the true effects were more protective than HRs of 0.80. To reduce the percentage of HRs < 0.80 to 10%, unmeasured confounder(s) would need to be associated with both dialysis initiation and mortality by relative risks of 4.05 (95% CI, 2.39-4.15), which is equivalent to shifting each study's estimated HR by 2.31-fold (95% CI, 1.51-2.36). Restricting studies to include only older patients did not modify the results.

Limitations

Limited number of studies and evidence on the absence of publication bias.

Conclusions

Our findings suggest that dialysis initiation considerably reduces mortality among adults with advanced CKD. Future bias-adjusted meta-analyses need to assess outcomes beyond mortality.

Sleep quality and risk of coronary heart disease - a prospective cohort study from the English longitudinal study of ageing

Background: The association between sleep quality and risk of coronary heart disease (CHD) remains unclear in the elderly.

Results: At eight-year follow up, a total of 411 (4.29%) participants developed CHD. Compared with good quality group, the multivariable hazard ratio [HR] (95% confidence interval [CI]) for CHD was 1.393 (1.005, 1.931) for intermediate quality group and 1.913 (1.206, 3.035) for poor quality group. Consistent results were observed in participants with normal sleep duration.

Conclusions: Poor sleep quality may be a novel modifiable risk factor for CHD in the elderly independent of conventional cardiovascular risk factors, even when sleep duration was normal.

Methods: The current study included 9570 CHD-free participants in the English Longitudinal Study of Ageing (ELSA) from wave 4 (2008 to 2009). Incident CHD included new onset angina or myocardial infarction. Sleep quality was measured by a four-item questionnaire. Score ranged from 1 (best) to 4 (poorest). Participants were divided into three groups: good quality (1 ≤ score <2), intermediate quality (2 ≤ score <3) and poor quality (3 ≤ score ≤4). Cox regression model was used to calculate HR for CHD risk according to sleep quality, adjusted for conventional CHD risk factors and sleep duration.

IPDN-China promotes the development of pediatric dialysis in China

BACKGROUND

In mainland China, dialysis for children with end-stage renal disease (ESRD) was not introduced until the 1980s. To describe the development of pediatric dialysis in different regions of China, a national pediatric dialysis network, namely, International Pediatric Dialysis Network-China (IPDN-China) ( www.pedpd.org.cn ), was launched in 2012.

METHODS

Original and updated information from the renal centers registered with the IPDN-China was collected between 2012 and 2016 from two sources, namely, the registry and the survey, and demographic features were analyzed.

RESULTS

Due to promotion by the IPDN-China, the number of registered renal centers increased from 12 to 39 between 2012 and 2016, with a significant increase in the coverage of the Chinese administrative divisions (from 26.5 to 67.6%) (p < 0.01); and the coverage of the pediatric (0~14 years old) population increased to nearly 90% in 2016. The distribution of renal centers indicated that East China had the highest average number of registered centers per million population (pmp) 0~14-year-old age group. Seventeen relatively large dialysis centers were distributed across 14 divisions. Various modalities of renal replacement therapy (RRT) were available in most centers. The IPDN-China has promoted collaborations between dieticians, psychologists, and social workers on dialysis teams to provide better service to children with ESRD and their families. The proportion of centers with all three types of paramedic support (i.e., dieticians, psychologists, and social workers) as well as the proportion of centers with a partial paramedic team significantly increased between 2012 (25.0%) and 2016 (69.2%) (p < 0.05). In terms of the point prevalent cases of patients (aged < 18 years), data from the survey of 39 registered centers revealed that the number of children with ESRD who were on RRT was 578 (49% received a kidney transplant) at the end of 2016, which was more than that reported in previous surveys. Data from the registry showed that 349 dialysis patients had been enrolled as of the end of 2016. The median age at RRT start was 9.5 years, and the leading cause of ESRD was congenital abnormalities of the kidney and urinary tract (CAKUT).

CONCLUSIONS

The IPDN-China has helped to promote the development of pediatric dialysis for ESRD in China by improving the organization of care for dialysis patients and increasing the availability and the quality of RRT for patients who need it. To improve knowledge about the epidemiology and outcomes of pediatric RRT around the country, a sustained effort needs to be made by the IPDN-China to increase the enrollment of dialysis patients and increase the number of registered centers in the future.

Children's effortful control moderates the relationship between parental psychological control and adolescents' depressive symptoms

The present study examined the interactions of adolescents' temperamental effortful control and parental psychological control on adolescents' depressive symptoms in China. A total of 440 adolescents between the ages of 14 and 20 years (M_age = 15.7) participated in this study. Data on parental psychological control, adolescents' depressive symptoms and effortful control were collected from self-reports. Results showed that adolescents' effortful control moderated the link between paternal psychological control and adolescents' depressive symptoms. Specifically, for adolescents with low levels of effortful control, paternal psychological control was positively associated with increased depressive symptoms whereas for adolescents with a high level of effortful control, this association was not significant. In addition, maternal psychological control was associated with adolescents' depressive symptoms. These findings confirmed and extended previous findings on the associations between parental psychological control, children's temperament effortful control, and depressive symptoms in adolescence.

Association of Hospital-Level Differences in Care With Outcomes Among Patients With Acute ST-Segment Elevation Myocardial Infarction in China

IMPORTANCE

The incidence of acute myocardial infarction has increased over the past decades in China, and management challenges include an unbalanced economy, disparate resources, and variable access to medical care across the nation.

OBJECTIVE

To examine the variations in care and outcomes of patients with ST-segment elevation myocardial infarction among 3 levels of hospitals in the typical Chinese public hospital model.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used data from the China Acute Myocardial Infarction Registry to compare the differences in care and outcomes among patients at 108 hospitals from 31 provinces and municipalities throughout mainland China. Participants included patients with ST-segment elevation myocardial infarction directly admitted to hospitals between January 2013 and September 2014. Data analyses were performed from June 2015 to June 2019.

EXPOSURES

Care in province-level, prefecture-level, or county-level hospitals in China.

MAIN OUTCOMES AND MEASURES

The primary outcome was in-hospital mortality. Secondary outcomes included presentation, treatments, and major complications.

RESULTS

A total of 12 695 patients (9593 men [75.6%]; median [interquartile range] age, 63 [54-72] years) were included; 3985 were at province-level hospitals, 6731 were at prefecture-level hospitals, and 1979 were at county-level hospitals. Compared with patients admitted to province-level hospitals, those admitted to prefecture-level and county-level hospitals were older (median [interquartile range] age, 61 [52-70] years vs 63 [54-72] years and 65 [57-75] years) and more likely to be women (815 women [20.5%] vs 1620 women [24.1%] and 667 women [33.7%]). Patients in prefecture-level and county-level hospitals were less likely to use ambulances compared with patients at province-level hospitals (11.6% [95% CI, 10.8%-12.4%] and 12.0% [95% CI, 10.6%-13.5%] vs 19.4% [95% CI, 18.1%-20.7%]; P < .001) and were less likely to experience early presentation, with onset-to-arrival times less than 12 hours for 75.3% (95% CI, 73.9%-76.6%) of patients at province-level hospitals, 70.8% (95% CI, 69.7%-71.9%) of patients at prefecture-level hospitals, and 69.8% (95% CI, 67.7%-71.8%) of patients at county-level hospitals (P < .001). The rates of reperfusion therapy were significantly lower in low-level hospitals (54.3% [95% CI, 53.1%-55.5%] for prefecture-level hospitals and 45.8% [95% CI, 43.6%-48.1%] for county-level hospitals) compared with province-level hospitals (69.4% [95% CI, 67.9%-70.8%]; P < .001). There was a progressively higher rate of in-hospital mortality at the 3 levels of hospitals: 3.1% (95% CI, 2.6%-3.7%) for province-level hospitals, 5.3% (95% CI, 4.8%-5.9%) for prefecture-level hospitals, and 10.2% (95% CI, 8.9%-11.7%) for county-level hospitals (P for trend < .001). After adjustment for patient characteristics, presentation, hospital facility, and treatments, the odds of death remained higher in prefecture-level (odds ratio, 1.39 [95% CI, 1.06-1.84]) and county-level (odds ratio, 1.43 [95% CI, 0.97-2.11]) hospitals compared with province-level hospitals (P for trend = .04).

CONCLUSIONS AND RELEVANCE

These findings suggest that there are significant variations in care and outcomes of patients among the 3 levels of hospitals in China. More efforts should be made to address the identified gaps, particularly in the prefecture-level and county-level hospitals. This work can inform national quality improvements efforts in China and in other developing countries.

A Practical Risk Score to Predict 24-Month Post-Discharge Mortality Risk in Patients With Non-ST-Segment Elevation Myocardial Infarction

BACKGROUND

Risk stratification of patients with non-ST-segment elevation myocardial infarction (NSTEMI) is important in terms of treatment strategy selection. Current efforts have focused on short-term risk prediction after discharge, but we aimed to establish a risk score to predict the 24-month mortality risk in survivors of NSTEMI.Methods and Results:A total of 5,509 patients diagnosed with NSTEMI between January 2013 and September 2014 were included. Primary endpoint was all-cause death at 24 months. A multivariable Cox regression model was used to establish a practical risk score based on independent risk factors of death. The risk score included 9 variables: age, body mass index, left ventricular ejection fraction, reperfusion therapy during hospitalization, Killip classification, prescription of diuretics at discharge, heart rate, and hemoglobin and creatinine levels. The C-statistics for the risk model were 0.83 (95% confidence interval [CI]: 0.81-0.85) and 0.83 (95% CI: 0.79-0.86) in the development and validation cohorts, respectively. Mortality risk increased significantly across groups: 1.34% in the low-risk group (score: 0-58), 5.40% in intermediate group (score: 59-93), and 23.87% in high-risk group (score: ≥94).

CONCLUSIONS

The current study established and validated a practical risk score based on 9 variables to predict 24-month mortality risk in patients who survive NSTEMI. This score could help identify patients who are at high risk for future adverse events who may benefit from good adherence to guideline-recommended secondary prevention treatment.

A novel tissue-engineered bone graft composed of silicon-substituted calcium phosphate, autogenous fine particulate bone powder and BMSCs promotes posterolateral spinal fusion in rabbits

Background

Autogenous bone graft is the gold standard bone grafting substrate available in spinal fusion because of its osteoconductive, osteogenic, and osteoinductive properties. However, several shortcomings including bleeding, infection, chronic pain, and nerve injury are known to be associated with the procedure. Bone tissue engineering has emerged as an alternative therapeutic strategy for bone grafts. New materials have been developed and tested that can substitute for the autogenous bone grafts used in the spinal fusion. The purpose of this study is to evaluate the role of a novel tissue-engineered bone graft with silicon-substituted calcium phosphate (Si-CaP), autogenous fine particulate bone powder (AFPBP), and bone marrow mesenchymal stem cells (BMSCs) using a rabbit posterolateral lumbar fusion model based on bone tissue engineering principles. The application of this graft can represent a novel choice for autogenous bone to reduce the amount of autogenous bone and promote spinal fusion.

Methods

BMSCs from New Zealand white rabbits were isolated and cultured in vitro. Then, BMSCs were marked by the cell tracker chloromethyl-benzamidodialkylcarbocyanine (CM-Dil). A total of 96 New Zealand White rabbits were randomly divided into four groups: (a) AFPBP, (b) Si-CaP, (c) Si-CaP/AFPBP, (d) Si-CaP/AFPBP/BMSCs.The rabbits underwent bilateral posterolateral spine arthrodesis of the L5-L6 intertransverse processes using different grafts. Spinal fusion and bone formation were evaluated at 4, 8, and 12 weeks after surgery by manual palpation, radiology, micro-computed tomography (micro-CT), histology, and scanning electronic microscopy (SEM).

Results

The rate of fusion by manual palpation was higher in the Si-CaP/AFPBP/BMSCs group than the other groups at 8 weeks. The fusion rates in the Si-CaP/AFPBP/BMSCs and the AFPBP groups both reached 100%, which was higher than the Si-CaP/AFPBP group (62.5%) (P ​> ​0.05) and Si-CaP group (37.5%) (P ​< ​0.05) at 12 weeks. New bone formation was observed in all groups after implantation by radiology and micro-CT. The radiographic and CT scores increased in all groups from 4 to 12 weeks, indicating a time-dependent osteogenetic process. The Si-CaP/AFPBP/BMSCs group showed a larger amount of newly formed bone than the Si-CaP/AFPBP and Si-CaP groups at 12 weeks. Bone formation in the Si-CaP/AFPBP/BMSCs group was similar to the AFPBP group. Histology showed that new bone formation continued and increased along with the degradation and absorption of Si-CaP and AFPBP from 4 to 12 weeks in the Si-CaP, Si-CaP/AFPBP, and Si-CaP/AFPBP/BMSCs groups. At 4 weeks, a higher proportion of bone was detected in the AFPBP group (23.49%) compared with the Si-CaP/AFPBP/BMSCs group (14.66%, P ​< ​0.05). In the Si-CaP/AFPBP/BMSCs group at 8 weeks, the area percentage of new bone formation was 28.56%, which was less than the AFPBP group (33.21%, P ​< ​0.05). No difference in bone volume was observed between the Si-CaP/AFPBP/BMSCs group (44.39%) and AFPBP group (45.06%) at 12 weeks (P ​> ​0.05). At 12 weeks, new trabecular were visible in the Si-CaP/AFPBP/BMSCs group by SEM. CM-Dil-positive cells were observed at all stages. Compared with histological images, BMSCs participate in various stages of osteogenesis by transforming into osteoblasts, chondrocytes, and osteocytes.

Conclusion

This study demonstrated for the first time that Si-CaP/AFPBP/BMSCs is a novel tissue-engineered bone graft with excellent bioactivity, biocompatibility, and biodegradability. The graft could reduce the amount of autogenous bone and promote spinal fusion in a rabbit posterolateral lumbar fusion model, representing a novel alternative to autogenous bone.

The Translational potential of this article

The translational potential of this article lies in that this graft will be a novel spinal fusion graft with great potential for clinical applications.

Developmental Trajectories of Shyness-Sensitivity from Middle Childhood to Early Adolescence in China: Contributions of Peer Preference and Mutual Friendship

This study examined trajectories of shyness-sensitivity and the contributions of peer relationships to these trajectories in Chinese children. Participants were 1061 school-age children (537 boys), initially in fifth grade (M_age = 11 years), in China. Longitudinal data on shyness-sensitivity were collected from peer assessments once a year for four years. In addition, peer nomination data on peer acceptance-rejection and mutual friendship were collected in the initial study. Four distinct shyness-sensitivity trajectories were identified: Low-Stable, Low-Increasing, Moderate-Decreasing, and High-Stable. Children with high peer acceptance scores were more likely to be in the High-Stable and Moderate-Decreasing trajectories than in the Low-Stable and Low-Increasing trajectories. The analysis of predictors of the within-trajectory growth rate indicated that children who were more liked by peers increased their shyness-sensitivity more slowly within the Low-Increasing trajectory and that children with mutual friendship involvement decreased their shyness-sensitivity more slowly within the Moderate-Decreasing trajectory. The results suggested that positive relationships might serve to attenuate developmental changes of shyness-sensitivity within these trajectories. The results were discussed in the Chinese context.

Behavioral Inhibition in Early Childhood and Adjustment in Late Adolescence in China

This study examined relations between behavioral inhibition in toddlerhood and social, school, and psychological adjustment in late adolescence in China. Data on behavioral inhibition were collected from a sample of 2-year-olds (initial N = 247). Follow-up data were collected at 7 years for peer relationships and 19 years for adjustment across domains. The results showed that early inhibition positively predicted later social competence and school adjustment. Peer relationships in middle childhood served as a protective factor in the development of depression of inhibited children. The results indicate the distinct functional meaning of behavioral inhibition in the Chinese context from a developmental perspective.

IL2RG-deficient minipigs generated via CRISPR/Cas9 technology support the growth of human melanoma-derived tumours

Objectives

Immunodeficient mice injected with human cancer cell lines have been used for human oncology studies and anti‐cancer drug trials for several decades. However, rodents are not ideal species for modelling human cancer because rodents are physiologically dissimilar to humans. Therefore, anti‐tumour drugs tested effective in rodents have a failure rate of 90% or higher in phase III clinical trials. Pigs are similar to humans in size, anatomy, physiology and drug metabolism rate, rendering them a desirable pre‐clinical animal model for assessing anti‐cancer drugs. However, xenogeneic immune rejection is a major barrier to the use of pigs as hosts for human tumours. Interleukin (IL)‐2 receptor γ (IL2RG), a common signalling subunit for multiple immune cytokines including IL‐2, IL‐4, IL‐7, IL‐9, IL‐15 and IL‐21, is required for proper lymphoid development.

Materials and Methods

IL2RG^−/Y pigs were generated by CRISPR/Cas9 technology, and examined for immunodeficiency and ability to support human oncogenesis.

Results

Compared to age‐matched wild‐type pigs, IL2RG^−/Y pigs exhibited a severely impaired immune system as shown by lymphopenia, lymphoid organ atrophy, poor immunoglobulin function, and T‐ and NK‐cell deficiency. Human melanoma Mel888 cells generated tumours in IL2RG^−/Y pigs but not in wild‐type littermates. The human tumours grew faster in IL2RG^−/Y pigs than in nude mice.

Conclusions

Our results indicate that these pigs are promising hosts for modelling human cancer in vivo, which may aid in the discovery and development of anti‐cancer drugs.