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 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.

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

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.

Objective To evaluate the application of cough reflex testing with various concentrations of citric acid for dysphagia post stroke. Methods 20 normal controls (NC), 20 stroke patients with dysphagia (SD) and 20 stroke patients without dysphagia (SND) were tested with cough reflex inhalated 4 kinds of dosage of citric acid: 0.2 mol/L, 0.4 mol/L, 0.6 mol/L and 0.8 mol/L. Results The incidence of pass (coughed twice or more) decreased in the SD compared with those in the NC as inhalated citric acid of 0.2 mol/L and 0.4 mol/L (P< 0.05), and decreased under 0.4 mol/L compared with the SND (P<0.05). There was no significant difference between the SND and the NC (P>0.05). 90% of the NC passed as inhalated citric acid of 0.4 mol/L; however, it was 45% in the SD, and increased when they inhalated more dosage of citric acid (P<0.05). The incidence of pass decreased under 0.2 mol/L citric acid in the SND compared with other concentration (P<0.05). The result of the test was reliable interrater (κ=0.97). The incidence of cough was consistent of 96.8% with the same concentration. No asthma and asphyxia was observed. Conclusion Cough reflex testing with citric acid inhalation can be used to assess the defensive function of airway in lower concentration for dysphagia after stroke.

BACKGROUND: Diffusion tensor imaging is a common technique applied for clinical studies of the brain, but it is rarely used for the diagnosis or prognosis of spinal cord injury. OBJECTIVE: To establish a rat model of spinal cord injury using micrological techniques, and to evaluate spinal cord transection with diffusion tensor imaging technology, thus providing a good animal model for further intervention. METHODS: Twelve healthy Sprague-Dawley rats were applied to establish spinal cord injury models using precise microscopic techniques, and another six rats in the sham operated group served as controls. Spinal cord transection of experimental rats after modeling was observed using diffusion tensor imaging. Motor evoked potentials and somatosensory evoked potentials were used to detect electrical physiological changes of rats.Neurological function changes of rats were evaluated using slope experiments and Basso, Beattie and Bresnahan scores. RESULTS AND CONCLUSION: After experimental rats regained consciousness, their lower extremities exhibited complete paralysis, the tails cannot swing, accompanying urinary retention. Diffusion tensor imaging displayed the T10 segment of spinal cord was completely transected. Motor and sensory evoked potential waveform were not drawn compared than control group. At 1 day, 1 week, 2 weeks, 4 weeks after operation, the test angle of slope experiments was less than 30° and Basso, Beattie and Bresnahan score was less than 10 points; as the time prolonged, lower limb irritating reflections of some rats were visible, but no initiative functional activity was found, local spinal cord structure were severely damaged. Precise microscopic techniques can successfully establish spinal cord injury model in rats, and diffusion tension imaging clearly visualizes the complete transection of the T10 spinal cord.

OBJECTIVETo explore clinical value of circular DNA in acute myocardial infarction.

METHODSVenous blood (2 ml/head) of 40 healthy control and 40 patients with acute myocardial infarction within 48h of onset of illness and convalescent period was collected. The level of plasma circular DNA was detected by duplex real-time polymerase chain reaction assay. The levels of myocardial enzyme spectrum and cardiac troponin T (cTnT) were detected by biochemistry method.

RESULTSThe level of circular DNA in control group and group of acute myocardial infarction before treatment was (21.5 +/- 10.7) ng/ml and (253.6 +/- 45.7) ng/ml, respectively (P = 0.000). The levels of serum myocardial enzyme spectrum and cTnT before treatment in patients with acute myocardial infarction were significantly higher than those of control group (P < 0.05). The level of circular DNA after treatment in patients with acute myocardial infarction was significantly decreased compared with that before treatment (P = 0.000), the levels of myocardial enzyme spectrum and cTnT were also significantly reduced (P < 0.05). There was significant correlation between the level of circular DNA and those of CK-MB and cTnT, r = 0.613, 0.654, P = 0.032, 0.021.

CONCLUSIONCircular DNA can be used as a marker of sensitively reflecting myocardial cell injury.

Aged ; Case-Control Studies ; DNA, Circular ; blood ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; blood ; diagnosis