Objective:To investigate the changes of gene or protein expression and activity of matrix metalloprotein9 (MMP9) and tissue inhibitor ofmetalloproteinasel (TIMP1) in the carotid artery (CA) of 4 wk hindlimb unweighted rat.Methods:A 4 weeks(wk) hindlimb unweighted (HU) rat model was used to simulate the effect of weightlessness on the cardiovascular system.Transmission electron microscopy was used to detect the content of ECM.Reverse transcriptase polymerase chain reaction(RT-PCR) was conducted to measure the mRNA content MMP and TIMP1.Immunohistochemistry and Western blot technique were used to measure the protein abundance.Gelatin zymography was carried out to detect the activity of MMP9.Results:Compared to the control group (CON),the area of ECM was enhanced (P＜0.05) and the content of collage fiber was increased (P＜0.05) in the CA of HU rats;moreover,HU did not affect the mRNA expression of MMP9,but significantly reduced the protein content (P＜0.05) or enzymatic activity (P＜0.05).Accordingly,the mRNA or protein expression of TIMP1 in the CA was significantly increased by HU (P＜0.05).Conclusion:Simulated weightlessness caused imbalance between MMP and TIMP1 expression,which might contribute to the ECM aggregation and stiffness of CA.

Military flying labor hygiene is a discipline that focuses on influences of special flight environment and labor condition on human body and related prevent measures, with the core of flight fatigue. Health information and technique training can help flight surgeons to enhance professional competency and improve the prevention and recovery of military flying fatigue. The course construction of teaching system in this study included survey of demand, arrangement of content, identification of strategy, determination of evaluation, and feedback of results. Meanwhile, the textbook compilation, cultivation of teaching team and construction of laboratory were also needed. After a 4-year practice, a formal teaching system has been established and its teaching effectiveness has basically fulfilled the professional requirement for flight surgeons.

OBJECTIVE: To carry out genetic diagnosis for a pedigree affected with cutis laxa. METHODS: Genomic DNA was extracted from peripheral blood samples from members of the pedigree and 50 unrelated healthy controls. Potential mutation was screened by next-generation sequencing and verified by Sanger sequencing. RESULTS: A heterozygous c.1985delG mutation was identified in the ELN gene among all patients from this pedigree. The same mutation was not found among unaffected family members and 50 healthy controls. CONCLUSION The genetic etiology for the pedigree has been elucidated, which has enabled genetic counseling and guidance for reproduction.
Cutis Laxa ; genetics ; Elastin ; genetics ; Heterozygote ; High-Throughput Nucleotide Sequencing ; Humans ; Mutation ; Pedigree

Objective:To explore the etiology, clinical diagnosis and treatment strategy of Lesch Nyhan syndrome.Methods:We retrospectively analyzed 2 patients with severe dyskinesia, mental retardation and complicated renal calculi who were admitted to the first people's Hospital of Zhengzhou in August 2019. Case 1, male, 9 years old, had multiple urinary calculi for 1 year. The patient came to the local hospital because double multiple kidney stones and bladder stonesa year ago. The patient had been treated with transurethral holmium laser lithotripsy for bladder stones. The results of infrared spectrum showed that the bladder stone was anhydrous uric acid stone. A week ago, color Doppler ultrasound showed multiple kidney stones and bladder stones. The patient was underdeveloped, mentally retarded and had a full-term cesarean section. There was no history of hypoxia, asphyxia and rescue of the patient. He had the following clinical manifestations: In the waking state, he was no language response to any stimulation. The nasolabial fold on the right was shallow and the corner of the mouth was oblique to the left. He lost the large movements such as lifting head, sitting alone, standing. The trunk showed torsion spasticity, limb muscle strength 2-3, limbs showing spastic hypertonia, limb joints stiff, hands showing fist-like, no involuntary movement and muscle fasciculation. The biceps reflex and knee tendon reflex were not elicited, and the pathological reflex was positive. Serum uric acid was 517 μmol/L. The Case 2 came from the same family, male, 6 years old, had the similar symptoms to his elder brother case 1. The family members complained on behalf of the child about intermittent fever for more than 2 years. The imaging examination of case 2 revealed kidney stones. Serum uric acid was 373 μmol/L. Whole Exome Sequencing and Sanger Sequencing were used to find the genetic causes of the two siblings. The NCBI-Homologene database was used to find the homologous sequence of the human HPRT1 gene, and the human HPRT1 gene sequence was compared with other species to analyze the protein conservation. The online website PredictProtein (http: //www.predactprotein) was used to predict the two-dimensional structure of the HPRT1 gene. The reported cases were summarized and same with the treatment plan.Results:A De novo mutation [c.571T>G(p.Tyr191Asp)] was found in the HPRT1 gene of the child, which was inherited from the mother. Lesch Nyhan syndrome can be diagnosed by the results of gene examination combined with clinical manifestations. The amino acid Tyr at the 191 position and the amino acids before and after it were highly conserved. Amino acid 191 was involved in the β-strand of the protein. We treated the patients with the lowest dose of allopurinol and children's conventional dose of potassium sodium bicitrate granules, and low purine diet. After 3 months of treatment, the serum uric acid was decreased, and the urinary calculi did not increase significantly.Conclusions:Combining with the clinical manifestations of children, HPRT1 gene might be the cause of pediatric disease and the two siblings could be diagnosed as Lesch-Nyhan syndrome. For such patients, the lowest dose of allopurinol and children's conventional dose of potassium sodium hydrogen citrate granule combined with diet could be more effective.

In recent years, with the increase of traffic accidents and the further development of aging, the incidence of pelvic fracture is gradually increasing. Based on the in-depth study about biomechanics of pelvic fracture fixation, the surgical treatment has been widely carried out. The purpose of surgical treatment is to effectively reduce and fix the fracture, correct deformity, restore integrity and stability of the pelvis, and minimize the complications caused by internal and external fixation. How to improve stability of the pelvis while ensuring therapeutic effect is a problem that every doctor will face in clinic. This paper summarizes the biomechanical research progress of pelvic fracture in recent years from the aspects of anatomy, normal biomechanics, classification and biomechanics of pelvic fracture fixation, so as to provide some references for reasonable treatment of pelvic fracture.

Objective:To explore the accuracy of array comparative genomic hybridization(aCGH) in the unexpected detection of Duchenne muscular dystrophy ( DMD) gene duplication/deletion in prenatal diagnosis. Methods:A retrospective analysis was performed on 31 cases with DMD gene duplication/deletion detected by aCGH among 5 025 prenatal diagnosis samples without family history of DMD in Henan Provincial People's Hospital from July 2018 to December 2019. The multiplex ligation-dependent probe amplification (MLPA) method was used to verify the above results. The American College of Medical Genetics and Genomics (ACMG) guideline was referred for pathogenicity analysis of the detected duplicates/deletions. Descriptive analysis was adopted in analysis. Results:The total unexpected DMD gene duplication/deletion rate was 0.62% (31/5 025), among which 25 cases were with microduplication/microdeletion ≤ 200 kb and six were >200 kb; there were 24 cases of deletion, seven cases of duplication; exon or intron duplication/deletion were accounted for 19 and 12 cases, respectively. According to the five classification standards of ACMG guideline, there were 17 cases with pathogenic variants and 14 cases with uncertain pathogenicity/likely benign variants. Of the 19 with exon mutations, 17 cases were DMD intragenic variants, and two cases involved variants in and outside DMD gene, which were verified by MLPA whose results were all positive. Conclusions:The duplication/deletion of exon region of DMD gene detected by aCGH technique is accurate and reliable, which plays an important role in the diagnosis of DMD. For these cases involved both internal and external regions of DMD gene, aCGH can identify the upstream and downstream breaking points of DMD gene, thus providing the basis for ACMG grading.