Objective:To investigate the effect of CT-derived fractional flow reserve (CT-FFR) measurement sites on the values and the diagnostic performance, and to determine the optimal measurement site for CT-FFR using invasive FFR as the reference standard.Methods:This study was part of the CT-FFR CHINA clinical trial. Patients with suspected coronary artery disease who were scheduled for invasive coronary angiography (ICA) were prospectively recruited from five clinical centers across the country from November 2018 to March 2020. Each enrolled patient underwent coronary CT angiography (CCTA), CT-FFR, ICA, and invasive pressure wire-based FFR assessments sequentially within one week. Four groups of CT-FFR values were obtained on each enrolled target vessels according to different CT-FFR measurement locations: 1, 2, 3 cm distal to the target lesion, and terminal vessel groups. Spearman and Bland-Altman analyses were used to explore the correlation and consistency of CT-FFR values and FFR values at different measurement sites. The measurement deviation of CT-FFR was also compared. Diagnostic accuracy and performance of CT-FFR, including sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC), in discriminating myocardial ischemia were analyzed across all measurement site groups on a per-vessel level, using FFR as the reference standard.Results:A total of 289 patients with 345 target lesion vessels were included. According to CCTA, there were 51 target vessels (14.8%) with<50% stenosis, 106 vessels (30.7%) with 50%-69% stenosis, and 188 vessels (54.5%) with stenosis≥70%. At per-vessel level, CT-FFR and FFR values at each measurement position group were highly positively correlated: 1 cm distal to target lesion group, r=0.734 ( P<0.001); 2 cm distal to target lesion group, r=0.732 ( P<0.001); 3 cm distal to target lesion group, r=0.737 ( P<0.001); terminal vessel group was 0.719 ( P<0.001). At per-vessel level, CT-FFR and FFR values of all measurement sites were in good agreement (Bland-Altman analysis results): 1 cm distal to target lesion group, 0.014 (95% LoA 0.002-0.026); 2 cm distal to target lesion group, 0.026 (95% LoA 0.015-0.038); 3 cm distal to target lesion group, 0.040 (95% LoA 0.039-0.051); terminal vessel group, 0.075 (95% LoA 0.064-0.087). And at per-vessel level, the accuracy of diagnosing myocardial ischemia with CT-FFR at 1 cm was highest [84.6% (95% CI 80.4%-88.3%)], and the lowest accuracy in the terminal vessel group [67.0% (95% CI 61.7%-72.0%)]. However, there was no significant difference in the diagnostic accuracy of CT-FFR at 1 cm, 2 cm [80.6% (95% CI 76.1%-84.6%)] and 3 cm [77.5% (95% CI 72.6%-81.7%)]. AUC of CT-FFR at 1 cm distal to the lesion were both highest for global level and moderately stenosis (50%-69%) lesions [0.85 (95% CI 0.81-0.89), 0.84 (95% CI 0.77-0.90)]. And the differences were statistically significant among the four measurement location groups (all P<0.05). Conclusions:The deviation of CT-FFR increases with measurement site distance distal to target lesions. One centimeter distal to the target lesion is the optimal measurement site, and the CT-FFR value here shows the highest diagnostic performance for myocardial ischemic lesions, especially for moderate stenosis.

Objective:To investigate the effect of CT-derived fractional flow reserve (CT-FFR) measurement sites on the values and the diagnostic performance, and to determine the optimal measurement site for CT-FFR using invasive FFR as the reference standard.Methods:This study was part of the CT-FFR CHINA clinical trial. Patients with suspected coronary artery disease who were scheduled for invasive coronary angiography (ICA) were prospectively recruited from five clinical centers across the country from November 2018 to March 2020. Each enrolled patient underwent coronary CT angiography (CCTA), CT-FFR, ICA, and invasive pressure wire-based FFR assessments sequentially within one week. Four groups of CT-FFR values were obtained on each enrolled target vessels according to different CT-FFR measurement locations: 1, 2, 3 cm distal to the target lesion, and terminal vessel groups. Spearman and Bland-Altman analyses were used to explore the correlation and consistency of CT-FFR values and FFR values at different measurement sites. The measurement deviation of CT-FFR was also compared. Diagnostic accuracy and performance of CT-FFR, including sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC), in discriminating myocardial ischemia were analyzed across all measurement site groups on a per-vessel level, using FFR as the reference standard.Results:A total of 289 patients with 345 target lesion vessels were included. According to CCTA, there were 51 target vessels (14.8%) with<50% stenosis, 106 vessels (30.7%) with 50%-69% stenosis, and 188 vessels (54.5%) with stenosis≥70%. At per-vessel level, CT-FFR and FFR values at each measurement position group were highly positively correlated: 1 cm distal to target lesion group, r=0.734 ( P<0.001); 2 cm distal to target lesion group, r=0.732 ( P<0.001); 3 cm distal to target lesion group, r=0.737 ( P<0.001); terminal vessel group was 0.719 ( P<0.001). At per-vessel level, CT-FFR and FFR values of all measurement sites were in good agreement (Bland-Altman analysis results): 1 cm distal to target lesion group, 0.014 (95% LoA 0.002-0.026); 2 cm distal to target lesion group, 0.026 (95% LoA 0.015-0.038); 3 cm distal to target lesion group, 0.040 (95% LoA 0.039-0.051); terminal vessel group, 0.075 (95% LoA 0.064-0.087). And at per-vessel level, the accuracy of diagnosing myocardial ischemia with CT-FFR at 1 cm was highest [84.6% (95% CI 80.4%-88.3%)], and the lowest accuracy in the terminal vessel group [67.0% (95% CI 61.7%-72.0%)]. However, there was no significant difference in the diagnostic accuracy of CT-FFR at 1 cm, 2 cm [80.6% (95% CI 76.1%-84.6%)] and 3 cm [77.5% (95% CI 72.6%-81.7%)]. AUC of CT-FFR at 1 cm distal to the lesion were both highest for global level and moderately stenosis (50%-69%) lesions [0.85 (95% CI 0.81-0.89), 0.84 (95% CI 0.77-0.90)]. And the differences were statistically significant among the four measurement location groups (all P<0.05). Conclusions:The deviation of CT-FFR increases with measurement site distance distal to target lesions. One centimeter distal to the target lesion is the optimal measurement site, and the CT-FFR value here shows the highest diagnostic performance for myocardial ischemic lesions, especially for moderate stenosis.

Objective To investigate the effects of microgravity environment on hibernating myoblasts.Methods Hibernating myoblasts were cultured under real and simulated microgravity conditions for 10 days.RNA-seq analysis and immunofluorescence are used to analysis the impact of microgravity environment on cell growth and gene expression of myoblasts.Results Under the microgravity conditions,genes associated with proliferation were upregulated.Under simulated microgravity,there were more and higher proportion of Ki67 positive cells compared to normal gravity conditions.Conclusion The microgravity environment promotes the proliferation of hibernating myoblasts.

Objective:To explore the impact of coronary CT angiography (CCTA) image quality and related factors on the diagnostic performance of CT-derived fractional flow reserve (CT-FFR).Methods:Based on the CT-FFR CHINA trial, the prospective multicenter trial enrolled patients with suspected coronary artery disease who underwent CCTA, CT-FFR and FFR measurement. The subjective and objective assessments of CCTA image were performed on a per-vessel level. The objective assessments included the enhancement degree of coronary artery, the signal-to-noise ratio (SNR) of the aortic root. We used χ 2 test and DeLong test to compare the diagnostic performance of CT-FFR with FFR as the reference standard in different subjective groups (non-artifact vs. artifact), enhancement degree of coronary artery groups (≤400 vs. 401-500 vs.>500 HU), SNR of the aortic root groups (≤16.9 vs.>16.9), body mass index (BMI) groups (<25 kg/m 2 vs.≥25 kg/m 2) and heart rate groups (<75 bpm vs.≥75 bpm). FFR and CT-FFR values≤0.80 was identified as myocardial ischemia. Results:The study enrolled 317 patients with 366 vessels. All target vessels in CCTA images were successfully analyzed by CT-FFR. The accuracy, sensitivity, specificity, positive predictive value, negative predictive value and AUC of the non-artifact group were 90.45%, 86.75%, 93.10%, 90.00%, 90.76% and 0.928, respectively, and those of the artifact group were 83.23%, 87.21%, 79.01%, 81.52%, 85.33% and 0.869, respectively. The differences in accuracy and specificity were statistically significant (χ 2=4.23, P=0.040; χ 2=8.55, P=0.003). The diagnostic efficacy of CT-FFR had no statistically significant differences among different objective groups (all P>0.05). Conclusions:The artifact of CCTA image has an effect on CT-FFR in the diagnosis of myocardial ischemia. The degree of vascular enhancement, SNR, BMI, and heart rate have no significant effect on the diagnostic performance of CT-FFR.

Prosthetic loosening and periprosthetic inflammation, as serious complications after joint replacement surgery, often require the secondary surgery for repair, which is easy to adversely affect the physical/mental health and economic status of patients.Studies have shown that the functional phenotype expressed by macrophages by different stimuli, namely macrophage polarization state, prolonged M1 polarization can lead to the continuation of long-term inflammation, while timely and effective M2 macrophage phenotype will lead to enhanced osteogenesis and tissue remodeling cytokine secretion and subsequent osseointegration, which play a crucial role in the development and outcome of prosthetic loosening and periprosthetic inflammation.The local micro-environment of extracellular matrix (ECM) is an important factor in the activation, migration, proliferation and fusion of macrophages. Researchers have deeply understood it mainly through the crosstalk between surface properties of biomaterials and macrophages. As an effector cell, macro-phages can perform complex spatiotemporal cellular functional responses by sensing the physical and chemical environment (surface topography, wettability, chemical composition, biological proteins) represented by surface properties of biomaterials.This paper summarizes the recent findings on macrophage polarization and material surface properties.

With the development of the 3rd-generation high-throughput sequencing technology and tissue engineering, recent studies show that many long-chain non-coding RNAs (LncRNAs) have played an important role in osteogenic differentiation of mesenchymal stem cells (MSCs). LncRNAs, which are involved in the regulation of mechanical regulation, further regulate bone-related cell functions and play a regulatory role at multiple levels, including transcription, post-transcriptional and epigenetic. LncRNAs may be involved in the osteogenic differentiation and bone remodeling of MSCs, the regulation of bone-related cell functions as a mechanical response molecule, as well as the pathological process of skeletal diseases.

OBJECTIVE: To explore clinical and genetic features of a pedigree affected with autosomal recessive neuromyotonia and axonal neuropathy (NMAN). METHODS: For the proband and her parents, clinical data was collected, genomic DNA was extracted from peripheral blood samples. Triplet primed-PCR was carried out to detect dynamic mutation of DMPK and ZNF9 genes, which are responsible for myotonic dystrophy, by capillary electrophoresis. High-throughput sequencing was used to screen variants of candidate genes for Mendelian disorders involving the nervous system. Candidate variants were confirmed by Sanger sequencing. The genotype of the variant was determined in the parents and 100 healthy controls. Pathogenicity of the variant was assessed by ACMG criterion. RESULTS: Mutation of DMPK and ZNF9 genes was excluded. DNA sequencing has identified a homozygous missense variant (c.335C>T, p.R119W) in the HINT1 gene. Both parents were found to carry the variant. The same variant was not found among the healthy controls. According to the ACMG criterion, the missense variant was classified as a pathogenic variant. CONCLUSION The c.335C>T (p.R119W) of the HINT1 gene probably underlie the disease in this pedigree. Above finding provided further evidence for the connection between HINT1 and NMAN and enriched the mutation spectrum of HINT1 gene.
Female ; Genotype ; Homozygote ; Humans ; Isaacs Syndrome ; genetics ; Nerve Tissue Proteins ; genetics ; Pedigree

Objective To construct a two-dimensional (2D) composite membrane and a three-dimensional (3D) biomimetic scaffold by silk fibroin (SF), type I collagen (Col-I) and hydroxyapatite (HA) blends in vitro, so as to study its physicochemical properties, as well as biocompatibility and explore the feasibility of its application in tissue engineering scaffold materials. Methods 2D composite membranes and 3D scaffolds were prepared by blending SF/Col-I/HA at the bottom of cell culture chamber and low temperature 3D printing combined with vacuum freeze drying. The biocompatibility was evaluated by mechanical property testing, scanning electron microscope and Micro-CT to examine the physicochemical properties of the material, and cell proliferation was detected to evaluate its biocompatibility. Results Stable 2D composite membrane and 3D porous structural scaffolds were obtained by blending and low temperature 3D printing. The mechanical properties were consistent. The pore size, water absorption, porosity and elastic modulus were all in accordance with the requirements of constructing tissue engineering bone. The scaffold was a grid-like white cube with good internal pore connectivity; HA was evenly distributed in the composite membrane, and the cells were attached to the composite membrane in a flat shape; the cells were distributed around pore walls of the scaffold. The shape of the shuttle was fusiform, and the growth and proliferation were good. Conclusions The composite membrane and 3D scaffold prepared by SF/Col-I/HA blending system had better pore connectivity and pore structure, which was beneficial to cell and tissue growth and nutrient transport. Its physicochemical properties and biocompatibility could meet the requirements of bone tissue engineering biomaterials.

BACKGROUND: Spinal cord injury is a damage to the spinal cord with a high morbidity that can be divided into primary and secondary injury. Secondary injury does more harm to the body than primary injury, which can be regulated and improved through proper interventions. In addition to the drugs, surgical decompression and other traditional treatments, hypothermia is an important physical intervention that has been shown to regulate secondary injury following spinal cord injury, and hold neuroprotective effect.OBJECTIVE: To introduce different hypothermia treatments for spinal cord injury and the effect on the disordered environment after spinal cord injury, as well as summarize the latest progression. METHODS: A computer-based search of CNKI and PubMed databases was conducted for the articles addressing the application of hypothermia in spinal cord injury published from January 2001 to June 2016, using the keywords of therapeutic hypothermia or low temperature, spinal cord injury in Chinese and English, respectively. RESULTS AND CONCLUSION: Hypothermia is divided into systematic and local hypothermia, and the former is simple and convenient, but it may lead to complications. Local hypothermia can quickly reach the target temperature, to make deep hypothermia at injury site and stablize the core temperature in the body, but it is invasive, and the necessary time of locating and maintaining effective temperature is a challenge. In general, hypothermia can improve the disordered microenvironment after spinal cord injury, reduce inflammatory infiltration, regulate the expression of relative genes and proteins, and promote the proliferation and differentiation of endogenous nerve cells. There are basic and clinical studies on hypothermia neuroprotection against spinal cord injury from various aspects; thereafter, hypothermia is a promising treatment strategy for spinal cord injury.

BACKGROUND:Peripheral nerve defect due to limb dysfunction has always been the difficulty faced by the medical profession. Ideal materials and processing technology for constructing a tissue engineering scaffold targeting peripheral nerve repair are stil in research stage. OBJECTIVE:To review the research progress in peripheral nerve repair using col agen/silk fibroin nerve conduits. METHODS:In this paper, the first author retrieved the PubMed and CNKI from 2003 to 2016 to search articles regarding methods of constructing artificial nerve scaffolds and selection of raw materials. Data from these articles were col ected, summarized and analyzed. RESULTS AND CONCLUSION:Forty-six articles were included for final analysis. Col agen and its degradation products trigger no inflammatory response in the host because of high biocompatibility and biodegradability. However, its use is largely limited by its rapid degradation and poor physical performance. Silk fibroin has a high flexibility and biocompatibility, and exhibits a slow degradation in vivo. As a rapid prototyping technique, three-dimensional printing can print various forms of scaffolds within a short time, characterized as high-quality pore structure and large-scale production. Given these, the col agen/silk fibroin nerve conduit prepared using the three-dimensional printing technology can maintain the biocompatibility and even improve the mechanical properties of the raw materials. Until now, more investigations on nerve repair using col agen or silk fibroin have been done, and we have never stopped improving the production process of these scaffolds. Therefore, the col agen/silk fibroin scaffold prepared using the three-dimensional printing technology is expected to become the main candidate for the repair of peripheral nerve defects.