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GH4710 nickel base alloy ingots， melted by VIM plus VAR， were subjected to trails of two-stage high-temperature homogenizing heat treatments， the microstructure and grain size of the ingots before and after heat treatment were analyzed by metallographic microscop. the distribution and content of alloy element in the ingot before and after heat treatment were evaluated by scanning electron microscope and electron probe， as well as to calculate the segregation index for alloying elements in different positions of ingots. Test result verified that， the two-stage homogenizing heat treatment at （1 150±50）℃×30 h-（1 200±10）℃×50 h， it could significantly eliminate the eutectic phase in the structure of GH 4710 ingot and reduce the element segregation in the ingot，and the mechanical properties of the forged bar are improved significantly. Under the test conditions of 980 ℃， 120 N/mm2， the persistence performance reached 126 h and 134 h， which was about double improvement compared with 53 h and 74 h of un-homogenizing heat treatment production. The persistent elongation rate has also increased by more than 50%.

ObjectiveA portable high-sensitivity X-ray fluorescence spectrometry method was established to directly and quickly determine the content of arsenic， cadmium and lead in wheat flour.MethodsPart of the sample was put into the sample cup， and then directly put the sample cup into the portable high-sensitivity X-ray fluorescence spectrometer for testing. The testing time， sample compactness， and testing thickness of the instrument were optimized and applied to the detection of different types of wheat flour.ResultsThe relative standard deviation （RSD， n=6） of the precision was between 0.6% and 4.8%， and the recovery rate was 78.3%-120.4%. The detection limits of lead， cadmium and arsenic were 0.06 mg/kg， 0.06 mg/kg， 0.05 mg/kg， the quantification limits were 0.19 mg/kg， 0.19 mg/kg and 0.17 mg/kg， respectively. The correlation coefficient of portable highly sensitive X-ray fluorescence spectrometry and inductively coupled plasma mass spectrometry was greater than 0.98.ConclusionThe method has relatively high precision， good detection limit and quantification limit， and can meet the requirements of simultaneous rapid detection of multiple heavy metal elements in wheat flour.

Objective: To explore the genetic etiology of a child with severe combined immunodeficiency (SCID)., Methods: Whole exome sequencing (WES) and copy number variation (CNV) analysis were carried out to screen potential variants in the proband. Suspected variants were validated by Sanger sequencing and qPCR., Results: WES showed that the proband harbored compound heterozygous variants of the DCLRE1C gene, namely deletion of exons 1-3 and c.322G>A (p.Val108Met) in exon 5. The exon 1-3 deletion was derived from his father and was known to be pathogenic, while the c.322G>A was derived from his mother and was unreported previously., Conclusion: The compound heterozygous variants of the DCLRE1C gene probably underlay the SCID in this child.

Objective: To explore the genetic basis for a child with succinate semialdehyde dehydrogenase deficiency., Methods: Peripheral blood samples of the proband and his parents were collected and subjected to Sanger sequencing. High-throughput sequencing was used to verify the gene variants. Bioinformatic software was used to analyze the pathogenicity of the variant sites., Results: Sanger sequencing showed that the proband carried a homozygous c.1529C>T (p.S510F) variant of the ALDH5A1 gene, for which his mother was a carrier. The same variant was not detected in his father. However, high-throughput sequencing revealed that the child and his father both had a deletion of ALDH5A1 gene fragment (chr6: 24 403 265-24 566 986)., Conclusion: The c.1529C>T variant of the ALDH5A1 gene and deletion of ALDH5A1 gene fragment probably underlay the disease in the child. High-throughput sequencing can detect site variation as well as deletion of gene fragment, which has enabled genetic diagnosis and counseling for the family.

Objective: To explore the genetic basis for a child with 46,XY disorders of sex development (DSD) and explore its genotype-phenotype correlation., Methods: The child was subjected to whole exome sequencing (WES), and exons 1 to 7 of NR5A1 were subjected to multiplex ligation-dependent probe amplification (MLPA) analysis., Results: The patient presented with rudimentary vulva of a female with Tanner stage 1. B-mode ultrasonography has detected ovary and uterus. The child was found to have a chromosome karyotype of 46,XY. WES revealed that the patient has harbored heterozygous deletion of exon 5 of the NR5A1 gene, which was a novel pathogenic variant inherited from the mother. No abnormality was found in the father., Conclusion: The main symptoms of 46,XY DSD children are insufficient external genitalia masculinization, for which variants of the NR5A1 gene are an important cause. WES has improved the detection rate of genetic variants and provided a solid basis for genetic counseling of the affected families.

Objective: To analyze the molecular etiology of a Chinese child affected with dihydropyrimidinase deficiency., Methods: Genomic DNA was extracted from peripheral blood samples of the family members. Pathogenic variant was determined by whole exome sequencing and verified by Sanger sequencing., Results: The child was found to harbor homozygous c.905G>A (p.Arg302Gln) variants in exon 5 of the DPYS gene, for which her parents were both heterozygous carriers., Conclusion: The homozygous c.905G>A (p.Arg302Gln) variants of the DPYS gene probably underlies the dihydropyrimidinase deficiency in the child. Above result has enabled genetic counseling and prenatal diagnosis for this family.

Objective To investigate the role and mechanism of endothelin receptor antagonist CPU0213 in myocardial ischemia-reperfusion (I/R) injury and oxidative stress injury. Methods In order to investigate the role of CPU0213 in I/R, SD rats were randomly divided into sham operation group, ischemia reperfusion injury (I/R) group, CPU0213 treatment group after I/R, CPU0213 and Janus kinase 2 (JAK2) specific inhibitor AG490 treatment group after I/R. In order to investigate the role of CPU0213 in oxidative stress damage, the isolated and characterized cardiomyocytes were cultured and divided into control group, H 2 O 2 oxidative stress group (H 2 O 2 group), oxidative stress damaged group treated with CPU0213, and oxidative stress damaged group treated with CPU0213 and AG490. The rat myocardial I/R models were constructed, and the rats and cardiomyocytes were treated with different treatments according to the experimental requirements. The rat heart was stained with triphenyltetrazolium chloride (TTC) to observe the area of myocardial infarction and the lactate dehydrogenase (LDH) and creatine kinase (CK) activity, flow cytometry to detect the apoptosis rate of cardiomyocytes, CCK-8 method to detect cell growth viability, Western blotting to detect the expression of Bcl2, JAK2, phosphorylated JAK2 (p-JAK2), caspase-3 and caspase-9, STAT3 and phosphorylated STAT3 (p-STAT3). Results After I/R injury in mice, CPU0213 treatment reduced myocardial infarction area, LDH, CK activity and apoptosis rate, but increased the phosphorylation level of JAK2 and STAT3. Compared with I/R combined with CPU0213, I/R combined with CPU0213 and AG490 increased the expression of caspase-3 and caspase-9, decreased significantly the expression of Bcl2 and the cell viability. After oxidative stress damage to cardiomyocytes, CPU0213 treatment reduced LDH, CK activity and cell apoptosis rate, and increased the phosphorylation level of JAK2 and STAT3. In the oxidative stress damaged group treated with CPU0213 and AG490, caspase-3 and caspase-9 expression increased, Bcl2 expression dropped significantly, cell viability decreased significantly. Conclusion The activation of JAK2/STAT3 pathway by CPU0213 can inhibit the apoptosis of cardiomyocytes induced by I/R and oxidative stress.

Objective: To establish reuse process of positive pressure powered air-filter protective hoods during coronavirus disease 2019 (COVID-19) epidemic., Methods: The procedure of pretreatment, storage, recovery, cleaning, disinfection and sterilization process of positive pressure powered air-filter protective hoods, which were used in the treatment of COVID-19 infection patients was established in Central Sterile Supply Department of the hospital. The cleaning and disinfection effects of the protective hoods after treatment were examined by magnifying glass method, residual protein detection method, real-time PCR, and agar pour plate method., Results: Twenty five used protective hoods underwent totally 135 times of washing, disinfecting and sterilizing procedures. After washing, all the protein residue tests and COVID-19 nucleic acid tests showed negative results. After sterilizing, all the protective hoods met sterility requirement. All the tested protective hoods were undamaged after reprocessing., Conclusions: The established reuse procedures for used positive pressure powered air-filter protective hoods are safe.

Objective: To analyze the clinical and molecular characteristics of a child with very long chain acyl-CoA dehydrogenase deficiency (VLCADD)., Methods: Peripheral blood sample of the patient was collected for the extraction of genomic DNA. Next generation sequencing (NGS) was carried out for the proband. Suspected mutations were validated by Sanger sequencing., Results: The patient, a 12-month-old girl, was admitted for diarrhea, vomiting, fever, poor spirit and decreased blood pressure. During the course of the disease, she also manifested hypertrophic cardiomyopathy, cardiogenic shock, elevated myocardial enzyme kinase, fever and metabolic acidosis, and had died after three days due to ventricular tachycardia and respiratory failure. Genetic testing showed that she has carried heterozygous mutations of of the ACADVL gene, namely c.664G>A (exon 8) and c.1056_1057del (exon 10). Blood screening for metabolic genetic diseases showed increased C12, C14, C16, C18, C14:1, C14:2, C16:1, C4/C3 and C8/C3, accompanied with decreased C0, C0/C16 and C8/C10. VLCADD and secondary carnitine deficiency could not be excluded, which was in keeping with the result of genetic testing., Conclusion: The child was diagnosed with VLCADD, which may be attributed to the compound heterozygous c.664G>A and c.1056_1057del variants of the ACADVL gene.

Objective: To carry out genetic testing for two families affected with cobalamin C (cblC) and establish a rapid method for the detection of a hotspot pathogenic variant c.609G>A of the MMACHC gene by using a PCR-high-resolution melting curve (PCR-HRM) method., Methods: Genomic DNA was extracted from peripheral blood samples of the probands and their parents. Potential variants of the MMACHC gene was analyzed by Sanger sequencing. The c.609G>A variant of the MMACHC gene was screened among 100 healthy children with the PCR-HRM method., Results: Sanger sequencing revealed that proband 1 carried compound heterozygous variants c.394C>T and c.609G>A of the MMACHC gene, while proband 2 carried compound heterozygous variants c.482G>A and c.609G>A of the same gene. PCR-HRM analysis of the two probands and the 100 healthy children were consistent with the Sanger sequencing., Conclusion: c.609G>A is a hotspot pathogenic variant of the MMACHC gene. The diagnosis of cblC may be rapidly attained through detection by PCR-HRM.

Objective: To assess the value of detecting the compositional features of carotid atherosclerotic plaques by 3.0T high resolution magnetic resonance imaging (MRI) in patients with coronary artery disease (CAD)., Methods: Consecutive 104 patients with coronary atherosclerosis confirmed by coronary angiography were prospectively recruited from January 2013 to January 2015 in Tiantan hospital. All patients were imaged with 3.0T high resolution MRI system. After exclusion patients with poor image quality, 97 patients were divided into 3 groups according to the degree of coronary artery stenosis: coronary atherosclerosis group (coronary stenosis between 1%-49%, n=16); single-vessel lesion group (single vessel lesion with stenosis between 50%-100%, n=48); multi-vessel lesion group (two or three vessel lesions with stenosis between 50%-100% or left main stem disease, n=33). The prevalence of total carotid plaque, calcified plaque, lipid-rich necrotic core, intra-plaque hemorrhage, plaque ulcer and rupture were compared among 3 groups., Results: The prevalence of total carotid plaque (81.3%(13/16), 72.9%(35/48), and 93.9%(31/33)) and calcified plaque (50.0%(8/16), 35.4%(17/48), and 42.4%(14/33)) were similar among the 3 groups (both P>0.05). The prevalence of carotid lipid-rich necrotic core in coronary atherosclerosis group was significantly lower than in single-vessel lesion group (18.8%(3/16) vs. 64.6%(31/48), P<0.01) and multi-vessel lesion group(18.8%(3/16) vs. 69.7%(23/33), P<0.01), but there was no significant difference between single-vessel lesion group and multi-vessel lesion group(P>0.05). Intra-plaque hemorrhage was detected in 2 patients of multi-vessel lesion group. There was no plaque ulcer or rupture in this cohort., Conclusion: Carotid plaque features are associated with the severity of coronary atherosclerosis in CAD patients.