Objective To investigate the variations of surface protein genes of avian influenza virus (AIV)before and after infecting mouse.Methods Mouse lung tissue was infected with A/Goose/Guangaong/NH/2003(H5N1)and the virus was isolated 12 hours and 9 days after replication in lung tissue of mouse.The isolated strains were amplified in embryonated chicken eggs,anti the virion RNA was transcribed into cDNA by reverse transeriptase.After amplification and purification,dideoxy-mediated chain termination was performed to detect synthetic oligonucleotide primers and DNA sequence was analyzed.Results The homology of nucleotide sequence for HA gene of three isolated strains was 99.6%-99.8%.and that of amino acid sequences was 99.3%-99.6%.The homology of nucleotide sequence for NA gene of three strains was 99.8%-99.9%.all of them were synonymous mutatinns.No variation was found in M gene.Conclusion After replication in mouse lung tissue,no significant mutation was found in the surface protein genes of AIV except some point mutations in HA genes.

Objective To estimate the averaged excess relative risk(ERR) in Chinese population based on the radiogenic cancer risk of leukemia in Japanese atomic bomb survivor cohort,and to discuss proper method suitable for risk transfer between populations.Methods Based on BEIR Ⅶ radiogenic cancer model and population transfer model,and the 2009 Chinese leukemia baseline rates given in 2012 Chinese Cancer Registry Annual Report,comparison was made of population incidences in seveal countries to adjust the weighting factors.Results The ERR of three subtypes of leukemia as a whole was obtained,and the weighting factors for risk transfer model was assumed.The additive factor for male was 0.2,and the multiplicative factor was 0.8,while the additive factor for female was 0.15,and the multiplicative factor was 0.85.Conclusions For the risk transfer between populations,weighting factor was adjusted as a whole to obtain the ERR value for estimating the risk to Chinese population.The risk transfer method suitable for Chinese population was obtained by using the incidence rate available for Chinese population to directly transfer radiation-induced leukemia risk to Chinese from Japanese.

BACKGROUND:Osteonecrosis of the femoral head is a common orthopedic disease,and hip preservation surgery with bone grafting is commonly used in the early stage,in which autologous bone and allograft bone are commonly used as bone grafting materials.However,autologous bone transplantation is highly traumatic and bone supply is limited,and allograft bone is rich in sources,but there are serious risks of immune rejection and absorption.In recent years,the tissue engineering technique based on mesenchymal stem cells is a new method for the treatment of femoral head necrosis,which is gradually widely used after basic experiments and clinical application. OBJECTIVE:To review the application and prospect of tissue engineering in the treatment of osteonecrosis of the femoral head to provide a new choice for the clinical treatment of osteonecrosis of the femoral head. METHODS:The PubMed database and CNKI database from 2013 to 2023 were searched by the first author with Chinese and English search terms"tissue engineering,mesenchymal stem cells,biological scaffolds,cytokines,osteonecrosis of the femoral head,bone graft,hip preservation".The articles on the treatment of osteonecrosis of the femoral head with tissue engineering technology were selected,and 55 representative articles were included for review after the initial screening of all articles according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION:(1)With the continuous development of biotechnology and materials science,great progress has been made in the treatment of osteonecrosis of the femoral head by bone tissue engineering,such as the application of gene-modified mesenchymal stem cells to repair osteonecrosis,the combination of gene recombination technology and surface modification technology with bone tissue engineering in the treatment of osteonecrosis of the femoral head.(2)When applied to the necrotic femoral head,tissue engineering technology can promote the regeneration of necrotic bone tissue and the repair of the vascular system,provide biomechanical stability for the necrotic area,and use bioactive factors to accelerate the repair of seed cells to complete the regeneration of new bone in necrotic area.(3)However,most of these studies are still in the animal experiment stage,and there are still many unsolved problems and challenges in bone tissue engineering research.With the rapid development of nanotechnology,tissue engineering and clinical medicine,biomimetic replacement bone grafting materials with perfect performance are expected to come into being.(4)In the future,bone tissue engineering for osteonecrosis of the femoral head is expected to be a satisfactory treatment for patients with hip preservation.

Objective:To evaluate the diagnostic value of 99Tc m-pyrophosphate (PYP) in transthyretin cardiac amyloidosis. Methods:From December 2018 to July 2019, 17 patients (9 males, 8 females, age: (53.4±13.0) years) with suspected cardiac amyloidosis underwent 99Tc m-PYP imaging in Peking Union Medical College Hospital were prospectively included. Visual score and semi-quantitative values (heart to contralateral ratio, H/CL) of 99Tc m-PYP uptake were used to diagnose transthyretin amyloidosis (ATTR). Biopsies and genetic measurements were also developed to evaluate the diagnostic value of the imaging. Results:Five of the 17 patients were diagnosed as ATTR with a visual score of 2-3, H/CL≥1.5, and confirmed with the biopsy or gene test. Four patients were diagnosed as ATTR with positive genetic results but no cardiac symptoms, and their visual scores were between 0 and 1 with H/CL<1.5. Considering the young age of the patients, amyloid deposition might have not yet caused visceral damage. Visual score of other 8 patients with negative 99Tc m-PYP imaging were also between 0 and 1 with H/CL<1.5, 2 of 8 were confirmed with light chain amyloidosis (AL) by biopsy, 3 were clinically diagnosed as AL and 3 were ATTR excluded. The accuracy of 99Tc m-PYP imaging for diagnosing ATTR was 11/11. Conclusion:99Tc m-PYP imaging is helpful for non-invasive diagnosis of transthyretin cardiac amyloidosis.

Objective:To investigate the application of different imaging methods of 99Tc m-pyrophosphate (PYP) in the diagnosis and pathological classification of cardiac amyloidosis (CA). Methods:A total of 31 patients (22 males, 9 females, age 21-81(57.2±13.4) years) with suspected CA who underwent 99Tc m-PYP dual-phase scintigraphy (early-phase: 1 h, delay-phase: 2-3 h) and SPECT/CT (1 h) between December 2018 and December 2019 in Peking Union Medical College Hospital were retrospectively included. Taking clinical diagnosis as the standard, the results of visual score (≥2, positive) and semi-quantitative values (heart to contralateral lung (H/CL)≥1.5, positive) of 99Tc m-PYP uptake in dual-phase scintigraphy and SPECT/CT imaging were analyzed. One-way analysis of variance and Bonferroni test were used to analyze the data. Results:Among 31 patients with suspected CA, 15 were clinically diagnosed as CA (5 patients with transthyretin-related CA (ATTR-CA) and 10 patients with light chain CA (AL-CA)) and 16 were diagnosed as non-CA. All 5 patients with ATTR-CA had positive dual-phase scintigraphy and SPECT/CT imaging results. Three out of 10 patients with AL-CA had positive early-phase scintigraphy whereas negative delay-phase scintigraphy and SPECT/CT imaging results. Sixteen patients who were clinically diagnosed as non-CA had negative dual-phase scintigraphy and SPECT/CT imaging results. The sensitivity (5/5), specificity (10/10), positive predictive value (5/5), negative predictive value (10/10) and accuracy (15/15) of delay-phase scintigraphy and SPECT/CT imaging were the same. Among 31 patients, 16 patients carried transthyretin-related (TTR) gene mutation, and 4 of them who clinically diagnosed as variant ATTR (ATTRv) had positive image findings while 12 of them who not clinically diagnosed as CA had negative image findings. There were significant differences in H/CL between ATTR-CA group and AL-CA group in early-phase (2.11±0.24 vs 1.31±0.07) and delay-phase (2.02±0.19 vs 1.30±0.05; F values: 75.41 and 87.15, Bonferroni test, both P<0.01). Conclusions:99Tc m-PYP delay-phase scintigraphy and SPECT/CT have high diagnostic efficiencies in ATTR-CA, helping to determine the pathological classification of CA; while early-phase scintigraphy has false positive results. Moreover, 99Tc m-PYP imaging is helpful to detect CA in patients with TTR gene mutation.

Objective: To investigate the expression of long non-coding RNA NUP50-AS1 (lncRNA NUP50-AS1) in esophageal squamous cell carcinomas (ESCC) tissues and cell lines, and to explore its effect on proliferation, migration and invasion of human esophageal cancer Eca109 cells. Methods: 49 pairs of ESCC tissues and corresponding para-cancerous tissues obtained from the Biological Specimen Base of the Fourth Hospital of Hebei Medical University during Jan. 2015 to Jan. 2016 were used in this study. qRT-PCR method was applied to detect the expression of NUP50-AS1 in collected tissues samples and five esophageal cancer cell lines (TE1, TE13, Eca109, Kyse150 and Kyse170). ShRNAs were transiently transfected into Eca109 cells to interfere the expression of NUP50AS1 gene, and finally, sh2-NUP50-AS1 was used for the following experiments. The effect of NUP50-AS1 gene knockdown on the proliferation of Eca109 cells was detected by MTS and colony formation assay; the effect of NUP50-AS1 gene knockdown on the migration of Eca109 cells was detected by scratch test, and the effect on cell invasion was detected by Transwell assay. Results: The expression of NUP50-AS1 in ESCC was correlated with the lymphnode metastasis and TNM stage (all P<0.01). The expression of NUP50AS1 in ESCC tissues was significantly higher than that in corresponding normal tissues (2.003±0.870 vs 1.000±0.000, P<0.05). The expression of NUP50-AS1 in five esophageal cancer cell lines was significantly up-regulated (P<0.05), and it had the highest expression in Eca109 cell line. After transfection, sh2-NUP50-AS1 had the highest transfection efficiency, and knocking down NUP50-AS1 gene significantly inhibited the proliferation, invasion and migration of the Eca109 cells. Conclusion: The expression of lncRNA NUP50AS1 in ESCC tissues was significantly higher than that in the para-cancerous tissues, and correlated with the TNM stage and lymphnode metastasis. The down-regulation of NUP50-AS1 inhibited the proliferation, invasion and migration of esophageal cancer cells. The high expression of NUP50-AS1 gene may be closely related to the occurrence and development of ESCC.

Amyloidosis is a disease caused by abnormal deposition of amyloid protein, and the main types of amyloidosis involving myocardium are light chain amyloidosis (AL) and transthyretin-related amyloidosis (ATTR). Different types of myocardial amyloidosis have different prognosis and treatment methods. Therefore, early diagnosis and classification are particularly important. Nuclear medical imaging can diagnose and classify myocardial amyloidosis noninvasively. Radiotracers for bone scintigraphy has high sensitivity and specificity for the diagnosis of ATTR, and have certain value for prognosis. Sympathetic innervation imaging tracers can detect cardiac sympathetic innervation, which may show myocardial involvement of amyloidosis earlier than bone scintigraphy. Amyloid protein specific imaging agent, which was first used in the diagnosis of amyloidosis in nervous system, has also yielded good results from preliminary studies in myocardial amyloidosis, and the diagnostic specificity in AL is slightly better than that in ATTR. This review introduces the application of nuclear medical imaging in myocardial amyloidosis.