Fast HDR image generation method from a single snapshot image based on frequency division multiplexing technology.

Traditional high dynamic range (HDR) image generation algorithms such as multi-exposure fusion need to capture multiple images for algorithm fusion, which is not only slow but also occupies a lot of storage space, which limits the application of multi-exposure fusion technology. In this paper, the frequency division multiplexing method is used to separate the sub-images with different exposure values from a single snapshot image successfully. The resolution of HDR images generated by this method is almost the same as that of the traditional multiple exposure methods, the storage space is greatly reduced and the imaging speed is improved.

The effects of IAM38 blocking or CD4 blocking on the binding of exogenous DNA in rabbit sperm.

The binding of exogenous DNA to sperm is a key process for sperm-mediated gene transfer; however, the underlying molecular mechanisms have yet to be elucidated. In the present study, we aimed to identify the DNA binding proteins (DBPs) in rabbit sperm and to gain further understanding of the molecular mechanism of sperm and exogenous DNA interaction. Native polyacrylamide gel electrophoresis was used for separating free sperm proteins and complexes of DNA fragment/sperm proteins. A distinct band was found after Coomassie blue staining, and seven potential proteins were identified by mass spectrometry analysis. An analysis of the physical/chemical properties of the seven proteins revealed that the sperm inner acrosomal membrane protein IAM38 (IAM38) matched the features of the DBPs. Western blotting analysis showed that the IAM38 and CD4 were present in the sperm but not in the seminal plasma. Blocking of the IAM38 impaired the DNA-binding capacity of the sperm. Blocking the CD4 decreased the DNA-uptake capacity of the sperm but did not influence the DNA-binding capacity of the sperm. Moreover, the EGFP-positive embryos and EGFP-positive blastocysts were also decreased after IAM38 blocking or CD4 blocking in comparison with the control group. In conclusion, our results imply that foreign DNA first binds to the transmembrane IAM38 of the sperm plasma membrane and then forms the complex of DNA/IAM38/CD4 with CD4 to complete the transportation of exogenous DNA into the nucleus of sperm.

Optimization of parthenogenetic activation of rabbit oocytes and development of rabbit embryo by somatic cell nuclear transfer.

The present study explored a suitable parthenogenetic activation (PA) procedure for rabbit oocytes and investigated the developmental potential of somatic cell nuclear transfer (SCNT) embryos using rabbit foetal fibroblasts (RFFs). The electrical activation had the optimal rate of blastocyst (14.06%) when oocytes were activated by three direct current (DC) pulses (40 V/mm, 20 µs each) followed by 6-dimethylaminopurine (6-DMAP) and cycloheximide (CHX) treatment; the blastocyst rate of ionomycin (ION) + 6-DMAP + CHX (12.07%) activation was higher than that of ION + 6-DMAP (8.6%) activation or ION + CHX (1.24%) activation; there was no significant difference in blastocyst rate between ION + 6-DMAP + CHX and DC + 6-DMAP + CHX groups. The blastocyst rate of ION + 6-DMAP + CHX-activated oocytes in the basic rabbit culture medium (M-199) + 10% foetal bovine serum (FBS; 14.28%) was higher than that in buffalo conditioned medium (5.75%) or G1/G2 medium (0), and the blastocyst rate was increased when M-199 + 10% FBS was supplemented with amino acids. Refreshing culture medium every day or every other day significantly increased the blastocyst rate. Treatment of donor cells with 0.5% FBS for 3-5 days increased blastocyst rate of SCNT embryos (33.33%) than no serum starvation (22.47%) or 0.5% FBS treatment for 6-9 days (23.61%); the blastocyst rate of SCNT embryos derived from nontransgenic RFFs was higher than that derived from transgenic RFFs by electroporation. The blastocyst development ability of SCNT embryos derived from RFFs by electroporation (32.22%) was higher than that of liposome (19.11%) or calcium phosphate (20.00%) transfection, and only the embryos from electroporation group have the EGFP expression (24.44%). In conclusion, this study for the first time systematically optimized the conditions for yield of rabbit embryo by SCNT.

Efficient generation of sFat-1 transgenic rabbits rich in n-3 polyunsaturated fatty acids by intracytoplasmic sperm injection.

N-3 polyunsaturated fatty acids (n-3 PUFAs) have their first double bond at the third carbon from the methyl end of the fatty-acid chain and had been proven to be beneficial to human health. However, mammals cannot produce n-3 PUFAs by themselves because they lack the n-3 fatty-acid desaturase (Fat-1) gene. Thus, the possibility of producing sFat-1 transgenic rabbits was explored in this study. The transgenic cassette of pPGK1-sFat-1-CMV-EGFP was constructed and transgenic rabbit embryos were produced by intracytoplasmic sperm injection (ICSI). When 123 EGFP-positive embryos at the 2-8-cell stage were transplanted into the oviduct of four oestrous-synchronised recipients, two of them became pregnant and gave birth to seven pups. However, transfer of embryos into the uterus of oestrous-synchronised recipients and oviduct or uterus of oocyte donor rabbits did not result in pregnancy. The integration of the sFat-1 gene was confirmed in six of the seven live pups by PCR and Southern blot. The expression of the sFat-1 gene in the six transgenic pups was also detected by reverse transcription polymerase chain reaction (RT-PCR). Gas chromatography-mass spectrometry analysis revealed that transgenic rabbits exhibited an ~15-fold decrease in the ratio of n-6:n-3 PUFAs in muscle compared with wild-type rabbits and non-transgenic rabbits. These results demonstrate that sFat-1 transgenic rabbits can be produced by ICSI and display a low ratio of n-6:n-3 PUFAs.

Identification and experimental validation of autophagy-related genes in abdominal aortic aneurysm.

AIM: Autophagy plays essential roles in abdominal aortic aneurysm (AAA) development and progression. The objective of this study was to verify the autophagy-related genes (ARGs) underlying AAA empirically and using bioinformatics analysis. METHODS: Two gene expression profile datasets GSE98278 and GSE57691 were downloaded from the Gene Expression Omnibus (GEO) database, and principal component analysis was performed. Following, the R software (version 4.0.0) was employed to analyze potentially differentially expressed genes related with AAA and autophagy. Subsequently, the candidate genes were screened using protein-protein interaction (PPI), gene ontology (GO) enrichment analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Finally, quantitative real-time polymerase chain reaction (RT-qPCR) was performed to detect the RNA expression levels of the top five selected abnormal ARGs in clinical samples obtained from the normal and AAA patients. RESULTS: According to the information contained (97 AAA patients and 10 healthy controls) in the two datasets, a total of 44 differentially expressed autophagy-related genes (6 up-regulated genes and 38 down-regulated genes) were screened. GO enrichment analysis of differentially expressed autophagy-related genes (DEARGs) demonstrated that some enrichment items were associated with inflammation, and PPI analysis indicated interaction between these genes. RT-qPCR results presented that the expression levels of IL6, PPARG, SOD1, and MAP1LC3B were in accordance with the bioinformatics prediction results acquired from the mRNA chip. CONCLUSION: Bioinformatics analysis identified 44 potential autophagy-related differentially expressed genes in AAA. Further verification by RT- qPCR presented that IL6, PPARG, SOD1, and MAP1LC3B may affect the development of AAA by regulating autophagy. These findings might help explain the pathogenesis of AAA and be helpful in its diagnosis and treatment.

The Role and Mechanism of SIRT6 in Regulating Phenotype Transformation of Vascular Smooth Muscle Cells in Abdominal Aortic Aneurysm.

BACKGROUND: Data mining of current gene expression databases has not been previously performed to determine whether sirtuin 6 (SIRT6) expression participates in the pathological process of abdominal aortic aneurysm (AAA). The present study was aimed at investigating the role and mechanism of SIRT6 in regulating phenotype transformation of vascular smooth muscle cells (VSMC) in AAA. METHODS: Three gene expression microarray datasets of AAA patients in the Gene Expression Omnibus (GEO) database and one dataset of SIRT6-knockout (KO) mice were selected, and the differentially expressed genes (DEGs) were identified using GEO2R. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of both the AAA-related DEGs and the SIRT6-related DEGs were conducted. RESULTS: GEO2R analysis showed that the expression of SIRT6 was downregulated for three groups and upregulated for one group in the three datasets, and none of them satisfied statistical significance. There were top 5 DEGs (KYNU, NPTX2, SCRG1, GRK5, and RGS5) in both of the human AAA group and SIRT6-KO mouse group. Top 25 ontology of the SIRT6-KO-related DEGs showed that several pathways including tryptophan catabolic process to kynurenine and negative regulation of cell growth were enriched in the tissues of thickness aortic wall biopsies of AAA patients. CONCLUSIONS: Although SIRT6 mRNA level itself did not change among AAA patients, SIRT6 may play an important role in regulating several signaling pathways with significant association with AAA, suggesting that SIRT6 mRNA upregulation is a protective factor for VSMC against AAA.

Profiling of the full-length transcriptome in abdominal aortic aneurysm using nanopore-based direct RNA sequencing.

Abdominal aortic aneurysm (AAA) is a common and serious disease with a high mortality rate, but its genetic determinants have not been fully identified. In this feasibility study, we aimed to elucidate the transcriptome profile of AAA and further reveal its molecular mechanisms through the Oxford Nanopore Technologies (ONT) MinION platform. Overall, 9574 novel transcripts and 781 genes were identified by comparing and analysing the redundant-removed transcripts of all samples with known reference genome annotations. We characterized the alternative splicing, alternative polyadenylation events and simple sequence repeat (SSR) loci information based on full-length transcriptome data, which would help us further understand the genome annotation and gene structure of AAA. Moreover, we proved that ONT methods were suitable for the identification of lncRNAs via identifying the comprehensive expression profile of lncRNAs in AAA. The results of differentially expressed transcript (DET) analysis showed that a total of 7044 transcripts were differentially expressed, of which 4278 were upregulated and 2766 were downregulated among two groups. In the KEGG analysis, 4071 annotated DETs were involved in human diseases, organismal systems and environmental information processing. These pilot findings might provide novel insights into the pathogenesis of AAA and provide new ideas for the optimization of personalized treatment of AAA, which is worthy of further study in subsequent studies.

Impact of prior endovascular interventions on outcomes of lower limb bypass surgery: A systematic review and meta-analysis.

The aim of this meta-analysis was to evaluate the mortality, amputation and complication rates in patients with peripheral lower limb arterial disease undergoing bypass surgery with or without a prior history of endovascular operation. A systematic literature screen was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines on four academic databases, Medline, Scopus, Embase and Cochrane Central Register of Controlled Trials. Out of 1,072 records, six articles involving 11,420 patients (mean age, 68.1±2.0 years) met the inclusion criteria. The findings presented a 2b level of evidence (i.e. overall evidence represents data from individual cohort study or low quality randomized controlled trials) and suggested lower mortality, amputation and complication rates for patients undergoing bypass surgery without any history of endovascular operation, compared with those with a history of prior endovascular operation. Moreover, a random-effect meta-analysis suggested a small, positive reduction in mortality (Hedge's g=0.08), amputation (Hedge's g=0.18) and complication rates (Hedge's g=0.05) for patients undergoing bypass surgery without any history of endovascular operation. Nevertheless, owing to the scarcity of high-quality data, further studies and randomized clinical trials are needed to confirm these effects.

A modified wire-loop snare technique for the retrieval of inferior vena cava filter with embedded hook.

Common obstacles to successful retrieval of retrievable inferior vena cave filter include embedded filter hook and severe tilt of the filter. We described a modified wire-loop snare technique using self-made fishhook-like pigtail catheter and 11-F-long sheath to retrieve a severe tilted filter with embedded hook successfully. The modified wire-loop snare technique is simple and effective requiring only standard equipment and single venous access. This technique may be suitable for some types of retrievable filter with embedded hook.

Altered patterns of gene expression distinguishing unruptured abdominal aortic aneurysms from ruptured ones: comprehensive analysis of inflammatory factors.

The purpose of this study was to profile altered patterns of gene expression that characterize abdominal aortic aneurysm and to compare these patterns between different conditions, unruptured (URA) and ruptured (RA). Full-thickness aortic wall tissues were obtained from patients during surgical repair of abdominal aortic aneurysm, including unruptured (n=29) and ruptured (n=11). RNA, protein and blood samples were prepared for each specimen, and differential levels of gene expression between unruptured and ruptured abdominal aortic tissues were assessed by immunohistochemistry, RT-qPCR and ELISA assays. Biochemical assay showed that triglyceride (TG), total cholesterol (TC) and low density lipoprotein (LDL) concentration in the peripheral blood of URA and UA patients with large size of aneurysm (>5 cm) was significantly increased compared with those with small size of aneurysm (3-5 cm). Of 7 genes examined, TRPV1, CAM, TNF-α, IL-6, MCP-1 and VCAM were significantly increased in RA patients compared with URA patients, which also showed markedly increased expression in large size of aneurysm, with TRPV1 and CAM exception in RA patients. Only PPARδ expression observed decrease in RA patients with larger size of aneurysm. Taken together, URA and RA exhibit distinct patterns of gene expression, with most alterations being unique to this disease. Abdominal aortic aneurysm arising in different sizes of aneurysm is thus characterized by a high degree of molecular heterogeneity, reflecting different pathophysiologic mechanisms.

Establishment and characterization of buffalo fetal fibroblasts induced with human telomerase reverse transcriptase.

Fetal fibroblasts are often used as donor cells for SCNT, but their short lifespan greatly limits this application. To provide stable and long-lifespan cells, buffalo fetal fibroblasts (BFFs) transfected with human telomerase reverse transcriptase (hTERT). The hTERT-transfected BFFs (hTERT-BFFs) were evaluated by qRT-PCR, Western blot, karyotype analysis, telomerase activity assay, growth curve assay, flow cytometry, and soft agar assay. The development of SCNT embryos derived from hTERT-BFFs was also assessed in vitro. The morphology of hTERT-BFFs was similar to the nontransfected BFFs, and the karyotype of hTERT-BFFs was normal at passage 30. The hTERT-BFFs at passage 4 and 30 had higher telomerase activity and extended proliferative lifespan with an increase in cell population at S phase when compared with nontransfected BFFs at passage 5 and 30. The mRNA expression of p53 in hTERT-BFFs at passage 5 and 30 remained unchanged when compared with nontransfected BFFs at passage 5, whereas the mRNA expression of p53 in the nontransfected BFFs at passage 30 was increased. Soft agar assay showed that hTERT-BFFs at passage 30 were not a malignant phenotype. Significantly, more SCNT embryos derived from hTERT-BFFs at passage 5 and 30 developed to blastocysts in comparison with BFFs at passage 30. The Caudal type homeobox 2 and Connexin 43 genes were indicated to involve in the development of cloned embryos. These results indicate that transfection of BFFs with hTERT can extend their lifespan and retain their basic and key biological characteristics in the status of primary BFFs.

Effect of miR-467b on atherosclerosis of rats.

OBJECTIVE: To observe the effect of miR-467b on the atherosclerosis (AS) of rats with apolipoprotein E (ApoE) gene knockout (ApoE(-/-)). METHODS: ApoE(-/-) rats were fed with high fat and high cholesterol diet and were randomly divided into group A, group B and group C, with 10 rats in each group. Group A: rats were injected with ApoE agonist through the caudal vein; group B: rats were injected with ApoE antagonist through the caudal vein; group C: as negative control group. Enzyme oxidation method was used to detect the blood lipid levels of rats. Western blotting method was used to detect the aortic lipoprotein lipase (LPL) expression levels of rats. HE staining and oil red O staining were performed to observe the AS lesions and lipid accumulation state. RESULTS: Compared with group C, blood lipid level, aortic intima and aortic sinus lipid accumulation area ratio, aortic sinus lesion area and LPL expression level in group A significantly reduced; while blood lipid level, aortic intima and aortic sinus lipid accumulation area ratio, aortic sinus lesion area, and LPL expression level in group B significantly increased, with the statistical difference (P < 0.05). CONCLUSIONS: miR-467b can alleviate the AS lesions of ApoE(-/-) rats, and its inhibiting effect on AS may be related to LPL expression.

HSP22 and its role in human neurological disease.

HSP22 (heat shock protein 22), belonging to the superfamily of small heat shock proteins, which has a molecular mass of 21.6 KD and is able to exist in the form of monomer, has multiple functions including molecular chaperones, apoptosis and anti-apoptosis, lifespan extension, antioxidation and so on. In recent years, studies show that HSP22 plays a crucial role in many neurological diseases, such as hereditary nerve endings disease, Alzheimer disease and Charco-Marie-Tooth. This review explores the progress in HSP22 and its involvement in human neurological disease.