Characterization of the novel HLA-A*24:191 allele and analysis of its MHC molecular modeling structure / 中华医学遗传学杂志

OBJECTIVE@#To characterize a novel HLA allele, A*24:191, its DNA sequence, MHC modeling structure, and the possible influence of the amino-acid residue variations on the molecule.@*METHODS@#The HLA sequence was determined by Luminex PCR-SSO and PCR-SBT. Its MHC molecular structure and the possible effects of the amino-acid residue variations were modeled and analyzed with Phyre2, RCSB PDB and HistoCheck software.@*RESULTS@#The PCR-SBT revealed the novel A*24:191 differs from A*24:02 in exon 2 at position 256, 265, 270 with G>C, G>C, A>T. The MHC molecular structure prediction showed that, compared with A*24:02, the 62nd residue of A*24:191 changed from the acidic E to a neutral Q, both with the side chain extending outside the α helix pointing forward the groove, (Risler's score, R=2), the 65th changed from the smaller neutral G extending inside the helix to a basic R with a long-chain extending upward outside the helix (R=52), and the 66th changed from the basic K to a neutral N both with a long side chain extending inside the groove (R=31). The above residues are located on the α helix of the α 1 domain which constituting the side wall of the peptide-binding groove. The DSS Score=3.85. From the surface image of the molecule, it can be clearly seen that the variations of the properties, sizes and configurations of the residues caused significant changes in the shape of the surface structure of the α helix.@*CONCLUSION@#It suggested that the residue variations are likely to change the peptide binding properties as well as the TCR and antibody binding characteristics of the molecule.

An investigation on the accuracy of a simple measurement method of glomerular filtration rate / 中华检验医学杂志

Objective:To evaluate the proper blood collection time and calculation formula by measuring the iohexol plasma clearance as a representative of glomerular filtration rate at the same time of routine enhanced computed tomography (CT) examination.Methods:The prospective study method was applied, and 9 subjects with normal renal function, who admitted in Civil Aviation General Hospital from September 2018 to June 2019, were included. A single bolus of a standard dose (5 ml) (iodine concentration: 350 mgI/ml) was injected. The concentration of iohexol was measured from heparin plasma at fasting state of the subject and at nine different times after the injection, respectively. More than 24 hours after the injection of the standard dose, an enhanced CT-level dose (50 ml) of iohexol was injected to the subject and the concentration of iohexol was measured at similar time points as the standard dose. Using a multi-point method of a standard dose as the standard, the clearance rate was calculated by three kinds of formulas including Groth and Aasted formula, Jacobsson formula and Fleming formula with the single-point method to assess iohexol plasma clearance at 0.5 to 8.0 hours post injection of enhanced CT-level dose. The correlation consistency and accuracy of the multi-point method and the single-point method, as well as the dual-point method and the single-point method were compared, and the proper blood collection time and calculation formula of the single-point method at regular enhanced CT-level dose were evaluated. The correlation between the multi-point method and the single-point method, as well as the dual-point method and the single-point method were assessed using Pearson correlation coefficient; the consistency between the multi-point method and the single-point method, as well as the dual-point method and the single-point method were assessed by bias using mean±standard deviation ( SD) and 95% confidence interval ( CI) of mean difference and so on. We assessed the concordance of GFR using GFR±5% ( P5),±10% ( P10) and 1±30% ( P30) intervals. Results:Compared with the multi-point method, the mean deviation of iohexol plasma clearance obtained by the three single-point methods increased gradually from 5 hours after the injection of iohexol ( P<0.05). Compared with the multi-point method, only 3 h results, which was calculated by the Groth and Aasted formula, reached a P value greater than 0.05, a correlation coefficient of 0.938, a mean deviation of (-5.2±8.8) ml·min -1·1.73 m -2, and the concordances were 100% corresponding to P30,77.8% corresponding to P10, and 66.7% corresponding to P5; the 2, 3 and 4 hours results, which was calculated by the Jacobsson formula, reached P values greater than 0.05, when the blood collection time was 3 hours, the correlation coefficient was 0.938, and the mean deviation was the smallest, which was (1.5±6.2) ml·min -1·1.73 m -2, and the concordances were 100% corresponding to P30, 88.9% corresponding to P10, and 66.7% corresponding to P5; the 2 and 3 hours results, which was calculated by the Fleming formula, reached P values greater than 0.05, when the blood collection time was 2 h, the correlation coefficient was 0.956, and the mean deviation was the smallest, which was (-4.5±8.8) ml·min -1·1.73 m -2, and the concordances were 100% corresponding to P30, 77.8% corresponding to P10, and 55.6% corresponding to P5,Compared with the dual-point method, when Groth or Aasted formula was used, the mean deviation was the smallest at 3 hours, which was (-5.3±5.7) ml·min -1·1.73 m -2; when Jacobsson formula was used, the mean deviation was the smallest at 2 hours, which was (1.6±1.6) ml·min -1·1.73 m -2; when Fleming formula was used, and the mean deviation was the smallest at 2 hours, which was (-4.6±4.0) ml·min -1·1.73 m -2. Conclusion:At a regular enhanced CT-level dose, one blood collection can accurately measure the glomerular filtration rate, the proper time for blood collection can be 3 hours after iohexol injection, and the appropriate calculation formula can be Jacobsson formula.

Establishment and performance evaluation of a wide-range high performance liquid chromatography method for determination of iohexol quantification / 中华检验医学杂志

Objective:To establish a method for iohexolquantification based on high performance liquid chromatography (HPLC) to measure the concentration of blood iohexolafterlow dose and contrast dose injection.Methods:Weperformed the method establishment and evaluation in this study. A HPLC-UV system (high performance liquid chromatography plus ultraviolet detector) was used to establish the method. The linearity, imprecision, recovery rate, limit of detection, lower limit of measuring interval and carryover of the method were evaluated. The stability of iohexol under different storage conditions, the differences of iohexolbetween serum and plasma concentrations, and the drug′s interference with the method were evaluated preliminarily. The single sample t test was used for the stability test of iohexolin samples, and the Wilcoxon symbol rank sum test was used for the comparison of iohexol concentrations between serum and plasma.Results:The linearity of iohexol ranging from 5 to 250 μg/ml ( R2=0.999 9) and from 250 to 4 000 μg/ml ( R2=0.999 8); when the concentration of iohexol was 20-3 000 μg/ml, the intra-and inter-assay coefficient of variation were 1.63% to 3.31% and 2.10% to 4.09%, respectively. The recovery rate was 94.17% to 106.13%; the limit of detection was 1 μg/ml and the lower limit of measuring interval was 5 μg/ml; it shows no carryover at the concentration of iohexol 4 000 μg/ml; after 48 hours at room temperature storage, the relative deviation of the concentration was -5.55% to +5.58%, after repeated freeze-thaw cycles 6 times at -80 ℃, the relative deviation of the concentration was -1.28% to+6.68%; there was no statistic difference between the measurement results between serum and plasma; valsartan and other drugs did not interfere with this methodsignificantly. Conclusion:Awide-range HPLC method for iohexolquantification has been established, which can stably and accurately detect the blood concentration of iohexol at low and contrast doses.

Sequence analysis and 3D molecular structure simulation of a novel HLA allele B*51: 159 / 中华医学遗传学杂志

Objective@#To identify a novel human leukocyte antigen (HLA) B allele in a Chinese Han individual and construct its three-dimensional structure.@*Methods@#The initial HLA genotyping was performed by PCR-sequence-based typing (PCR-SBT). The ambiguous allele was confirmed with single-strand DNA sequencing. The DNA sequence was analyzed to identify the difference between the novel allele and its closest matching allele. Finally, the three-dimensional molecular structure of the novel allele was constructed using a Swiss-Model.@*Results@#One allele of the subject at the HLA-B locus was B*44: 03: 01, whilst the other was a novel allele which differed from the closest matching allele B*51: 01: 01: 01 by nucleotide (nt) 329 A>C in exon 2, resulting in an amino acid change at codon 86 (p.Asn86Thr).@*Conclusion@#A novel HLA-B allele has been identified and officially named as HLA-B*51: 159 by the WHO Nomenclature Committee for Factors of the HLA System. The three-dimensional structure of B*51: 159 was simulated.

Sequence analysis and 3D molecular structure simulation of a novel HLA allele B*51:159 / 中华医学遗传学杂志

OBJECTIVE@#To identify a novel human leukocyte antigen (HLA) B allele in a Chinese Han individual and construct its three-dimensional structure.@*METHODS@#The initial HLA genotyping was performed by PCR-sequence-based typing (PCR-SBT). The ambiguous allele was confirmed with single-strand DNA sequencing. The DNA sequence was analyzed to identify the difference between the novel allele and its closest matching allele. Finally, the three-dimensional molecular structure of the novel allele was constructed using a Swiss-Model.@*RESULTS@#One allele of the subject at the HLA-B locus was B*44:03:01, whilst the other was a novel allele which differed from the closest matching allele B*51:01:01:01 by nucleotide (nt) 329 A to C in exon 2, resulting in an amino acid change at codon 86 (p.Asn86Thr).@*CONCLUSION@#A novel HLA-B allele has been identified and officially named as HLA-B*51:159 by the WHO Nomenclature Committee for Factors of the HLA System. The three-dimensional structure of B*51:159 was simulated.

Comparison of long-term effect between minimally invasive and open approaches in one-level posterior lumbar inter-body fusion: a 10-12 year prospective study / 中华骨科杂志

Objective To compare the long-term effect between minimally invasive (MIS) and open approaches in one-level posterior lumbar interbody fusion (O-PLIF) after more than 10 years follow up. Methods All 131 patients (lumbar spine le-sions) in our hospital were randomized into MIS-PLIF group and O-PLIF group from March 2006 to March 2008. In MIS-PLIF group, there are 66 patients, 34 males and 32 females, with the average of 52.3 ± 6.7 years old (range from 40 to 63). In O-PLIF group, there are 65 patients, 29 males and 36 females, with the average of 51.1 ± 6.9 years old (range from 46 to 63). Regarding March 2018 as last follow-up, differences in intervertebral disc height and segmental lordosis restoration of the operation segment , lumbar lordosis restoration, multifidus cross section area (CSA), multifidus atrophy rate, fusion rate, visual analogue scale (VAS) for back and leg pain, Oswestry Disability Index(ODI), Japanese Orthopaedic Association cores (JOA) and postoperative long-term compli-cations were evaluated between the two groups. The related risk factors of postoperative long-term complications were evaluated in further analysis. Results Complete follow-up data were available on 37 patients in MIS-PLIF group and 35 patients in O-PLIF group, with the follow-up rate of 56.1％and 53.8％respectively,and with the mean follow-up time of 134.5 ±8.4 and 137.1±5.8 months respectively. At three time nodes of one year after operation, five years after operation and last follow-up after operation, there were significant differences in lumbar lordosis restoration (one year after operation and last follow-up after operation)( 5.0°± 2.3° vs. 3.9°±1.4°;4.7°±2.4° vs. 3.7°±1.5°), multifidus CSA (965.4±164.9 mm2 vs. 884.9±168.2 mm2;891.1±155.9 mm2 vs. 783.2± 163.0 mm2; 764.8 ± 148.3 mm2 vs. 643.5 ± 150.0 mm2), multifidus atrophy rate (8.5％± 2.5％ vs. 16.6％± 5.8％; 15.6％± 3.5％ vs. 26.2％±7.4％;27.6％±6.5％vs. 39.3％±9.3％), postoperative VAS for back pain (2.2±1.0 vs. 2.9±1.2;1.7±0.9 vs. 2.2±1.0;1.4±1.0 vs. 2.2±1.2), JOA score (22.3±3.8 vs. 19.9±4.2;23.1±4.3 vs. 19.3±3.9;22.4±4.2 vs. 19.6±4.0) and ODI (11.6％±4.8％vs. 22.0％± 7.7％;9.4％±3.9％vs. 12.3％±4.9％;8.6％±4.0％vs. 11.0％±4.6％) between the two groups (P<0.05). However, there were no sig-nificant differences in segmental lordosis, intervertebral height restoration, lumbar lordosis restoration (one year after operation), fusion rate or postoperative VAS for leg pain between MIS-PLIF and O-PLIF(P>0.05). Intractable back pain and adjacent segment disease were the major postoperative long-term complications for MIS-PLIF group (3 cases and 2 cases) and O-PLIF group (10 cas-es and 7 cases), and the difference was statistically significant in the intractable back pain incidence rate ( 8.5％vs. 28.6％,χ2=5.090, P=0.024), but not in the adjacent segment disease(5.4％vs. 20％,χ2=0.002, P=0.061). What's more, patients with intracta-ble back pain suffered more obviously multifidus atrophy than patients without intractable back pain at three time nodes of one year after operation (19.4±4.4％vs. 10.9±5.1％, P<0.05), five years after operation (30.2±5.4％vs. 18.7±6.7％, P<0.05) and last fol-low-up after operation (44.5±5.7％vs. 30.8±8.9％, P<0.05) . Conclusion In the long-term follow up, compared with O-PLIF, MIS-PLIF had advantages in better maintenance of lumbar lordosis, protection of the multifidus muscle, reduced lower back pain, JOA score, ODI score and intractable back pain incidence rate. Multifidus atrophy may be a related risk factor of intractable back pain.

Tomography Study on Total Flavonoids from Rhizoma Drynariae in Promoting New Bone Formation in Distraction Osteogenesis Rat Model / 广州中医药大学学报

Objective To establish a distraction osteogenesis SD rat model for exploring the effect of total flavonoids from Rhizoma Drynariae on the quality of rat bone formation in the process of distraction osteogenesis from the perspective of tomography.Methods Twenty-four rats were randomly divided into experimental group and control group after successful modeling,and were respectively given intragastric administration with total flavonoids from Rhizoma Drynariae(in dose of 77.125 mg/kg) and saline for 8 weeks.Seven days after operation,the tibias of all the rats were given distraction at the speed of 0.2 mm for 20 days.Eight weeks after the operation,X-ray examination for all the rats was performed,and then the rats were killed for obtaining the tibia samples for Micro-CT scanning.The differences of X-ray Lane-Sandhu scores,the bone mineral density and bone mineral content were compared between the two groups.Results The X-ray Lane-Sandhu scores,the bone mineral density and bone mineral contents showed by Micro-CT scanning in the experimental group were higher than those in the control group,and the differences were statistically significant (P ＜ 0.05).Conclusion The total flavonoids from Rhizoma Drynariae can improve the quality of bone formation in the process of distraction osteogenesis in rats.

Ray-tracing by use of optical design software ZEMAX:Correlation of intraocular lens forward movement with human eye diopter adjustment / 中国组织工程研究

BACKGROUND: The intraocular lens can move forward during cataract optic capsular surgery,but the changes in the human eye diopter cannot be monitored in such a dynamically adjustment process,it is difficult to obtain clinical data which could reveal the correlation between intraocular lens forward and human eye diopter adjustment.OBJECTIVE: To observe the influence of intraocular lens movement on the adjustment of human eye diopter.METHODS: Based on Hwey-Lan Liou eye model,using optical design software ZEMAX to realize ray tracing,the relationship of intraocular lens forward in the eye with the adjustment of human eye diopter was investigated.RESULTS AND CONCLUSION: Once the intraocular lens forward for a certain distance,human eye obtained the amount of accommodating diopter was not constant; the adjustment amount depended on the axial length and the required intraocular lens implantation,especially in axial length; for the intraocular lens forward of the surgical eyes at different axial lengths,the amount of accommodating human eye diopter was negatively correlated with axial length.

Coronary Artery Imaging in Patients with High Heart Rate by Dual-source CT:The Initial Experience / 实用放射学杂志

Objective To explore the scanning technique and image quality of coronary artery imaging with dual-source CT without oral Betaloc preparation in the patients with high heart rate.Methods 412 cases were undergone coronary imaging with dual-source CT (including plain and enhanced scans) ,among them,there were 30 cases with heart rate more than 100 bpm.Multi-planar reconstruction(MPR),maximum intensity projection(MIP) and volume rendering (VR) were performed using contrast-enhanced images.The image quality was classified into 3 grades, and coronary segments named according to AHA standard were evaluated.Results The average heart rate during enhanced scan in the 30 cases was (115.6?11.8)(101～139)bpm,the average breath hold time was (5.7?1.2) s.The best reconstruction phase was in the systolic phase. Altogether 424 coronary segments were evaluated, among them 93.9%(398/424)belonged to the first grade,5.0%(21/424)belonged to the second grade,and 1.2%(5/424) belonged to the third grade. Conclusion Without oral administration of Betaloc preparation, good coronary artery images can be obtained in the patients with high heart rate by dual-source CT.

Coronary artery imaging with dual-source CT:initial experience / 中华放射学杂志

Objective To explore the scan technique and image quality of coronary artery imaging with dual-source CT without oral Betaloc preparation.Methods Plain and enhanced dual-source CT coronary artery imaging without oral Betaloc preparation was performed in 215 patients with clinically suspected coronary heart disease or early-stage coronary lesions.Calcium scoring with plain scan images and multi-planar reconstruction(MPR),maximum intensity projection(MIP)and volume rendering technique (VRT)reconstruction with enhanced scan images were made in all cases.The scan technique and post reconstruction experience was summarized.The image quality was classified as three grades,and coronary segments classified according to AHA standards were evaluated.Results The median of calcium score of the 215 cases was 82.2(2.3—1827.9).The average heart rate of the enhanced scan was(80.6?15.3) (57—139)bpm.The post reconstruction methods with which coronary segments could be shown as best as possible consisted of(1)multiphases screening methods,(2)bi-phase or multiple-phase complement method,and(3)premature beat removing or arrhythmia shifting method.Altogether 3026 coronary segments were evaluated,among them 97.5% were evaluated as grade 1 image quality,2.0% were evaluated as grade 2 and 0.5% were evaluated as grade 3.The coronary segments in 91 cases were completely normal, while 112 segments with