Publications by authors named "Yi Dong"

698 Publications

WFUMB position paper. Incidental findings of the salivary glands.

Med Ultrason 2021 Jun 8. Epub 2021 Jun 8.

Department Allgemeine Innere Medizin (DAIM) Kliniken Hirslanden Beau Site, Salem und Permanence, Bern, Switzerland.

A salivary incidentaloma (SI) stands for any focal salivary lesion, independent of size, discovered by any imaging method including ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), multimodal positron emis-sion tomography (PET) combined with CT or MRI, or X-ray imaging, performed for another reason, in the absence of known salivary glands' disease. The article presents a detailed analysis of salivary gland diseases with the emphasis on neoplasms. It describes frequency of SIs found on imaging, their prevalence, epidemiology and clinical significance. The probability of malignancy or malignant transformation of a SI, its imaging features, recommended treatment, management and follow-up, as well as ethical issues, psychological burden, informed decision making, economical consequences and costs are discussed. The general prevalence of SIs is low, but is dramatically increasing over time, and may rise significantly in selected groups of oncologic patients. SIs most frequently turn out to be benign primary neoplasms or pseudotumors, including intraparenchymal lymph nodes. SIs detected by other imaging methods should be subsequently assessed with US. Solid SIs demand ultrasound guided fine-needle aspiration cytology (US-FNAC). Neoplasms should undergo surgery. Post-operative US follow-up is man-datory for malignant tumors and recommended for benign neoplasms.
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http://dx.doi.org/10.11152/mu-3283DOI Listing
June 2021

CT/MRI LI-RADS v2018 vs. CEUS LI-RADS v2017-Can Things Be Put Together?

Biology (Basel) 2021 May 6;10(5). Epub 2021 May 6.

Department Allgemeine Innere Medizin (DAIM), Kliniken Hirslanden Beau Site, Salem und Permancence, 3013 Bern, Switzerland.

Different LI-RADS core documents were released for CEUS and for CT/MRI. Both documents rely on major and ancillary diagnostic criteria. The present paper offers an exhaustive comparison of the two documents focusing on the similarities, but especially on the differences, complementarity, and added value of imaging techniques in classifying liver nodules in cirrhotic livers. The major diagnostic criteria are defined, and the sensitivity and specificity of each major diagnostic criteria are presented according to the literature. The existing differences between techniques in assessing the major diagnostic features can be then exploited in order to ensure a better classification and a better clinical management of liver nodules in cirrhotic livers. Ancillary features depend on the imaging technique used, and their presence can upgrade or downgrade the LI-RADS score of an observation, but only as far as LI-RADS 4. MRI is the imaging technique that provides the greatest number of ancillary features, whereas CEUS has fewer ancillary features than other imaging techniques. In the final part of the manuscript, some recommendations are made by the authors in order to guidephysicians as to when adding another imaging technique can be helpful in managing liver nodules in cirrhotic livers.
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http://dx.doi.org/10.3390/biology10050412DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8148521PMC
May 2021

WFUMB Position Paper-Incidental Findings, How to Manage: Spleen.

Ultrasound Med Biol 2021 May 26. Epub 2021 May 26.

Department Allgemeine Innere Medizin (DAIM), Kliniken Hirslanden Beau Site, Salem und Permancence, Bern, Switzerland. Electronic address:

The World Federation for Ultrasound in Medicine and Biology (WFUMB) is addressing the issue of incidental findings (IFs) with a series of publications entitled "Incidental Imaging Findings-The Role of Medical Ultrasound." IFs are less commonly encountered in the spleen than in many other abdominal organs but remain a frequent dilemma in clinical practice. A histological diagnosis is rarely necessary for patient management. Many IFs, such as secondary spleens and splenic cysts, are harmless and do not require any further investigation. The diagnosis of many other focal splenic lesions is, however, often problematic. The following overview is intended to illustrate a variety of incidentally detected spleen pathologies such as size variants, shape variants, secondary spleens, focal splenic lesions and splenic calcifications. It should aid the examiner in establishing the diagnosis. Moreover, it should help the ultrasound practitioner decide which pathologies need no further investigation, those requiring interval imaging and cases in which immediate further diagnostic procedures are required.
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http://dx.doi.org/10.1016/j.ultrasmedbio.2021.03.032DOI Listing
May 2021

Pre-supplementary motor network connectivity and clinical outcome of magnetic stimulation in obsessive-compulsive disorder.

Hum Brain Mapp 2021 May 29. Epub 2021 May 29.

Department of Neurology, The First Affiliated Hospital of Anhui Medical University, The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China.

A large proportion of patients with obsessive-compulsive disorder (OCD) respond unsatisfactorily to pharmacological and psychological treatments. An alternative novel treatment for these patients is repetitive transcranial magnetic stimulation (rTMS). This study aimed to investigate the underlying neural mechanism of rTMS treatment in OCD patients. A total of 37 patients with OCD were randomized to receive real or sham 1-Hz rTMS (14 days, 30 min/day) over the right pre-supplementary motor area (preSMA). Resting-state functional magnetic resonance imaging data were collected before and after rTMS treatment. The individualized target was defined by a personalized functional connectivity map of the subthalamic nucleus. After treatment, patients in the real group showed a better improvement in the Yale-Brown Obsessive Compulsive Scale than the sham group (F  = 6.0, p = .019). To show the neural mechanism involved, we identified an "ideal target connectivity" before treatment. Leave-one-out cross-validation indicated that this connectivity pattern can significantly predict patients' symptom improvements (r = .60, p = .009). After real treatment, the average connectivity strength of the target network significantly decreased in the real but not in the sham group. This network-level change was cross-validated in three independent datasets. Altogether, these findings suggest that personalized magnetic stimulation on preSMA may alleviate obsessive-compulsive symptoms by decreasing the connectivity strength of the target network.
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http://dx.doi.org/10.1002/hbm.25468DOI Listing
May 2021

Plasma interleukin-6 is a potential predictive biomarker for postoperative delirium among acute type a aortic dissection patients treated with open surgical repair.

J Cardiothorac Surg 2021 May 27;16(1):146. Epub 2021 May 27.

Department of Cardiovascular Surgery, Union Hospital, Fujian Medical University, Xinquan Road No. 29, Fuzhou, 350001, Fujian, China.

Objectives: The relationship between inflammatory cytokines and postoperative delirium (POD) remains to be further investigated, especially in patients undergoing acute type A aortic dissection (AAD). Interleukin-6 (IL-6) is involved in the inflammatory process and has recently been identified as a biomarker of cerebral dysfunction. We explored the hypothesis that IL-6 was one of the critical causes of POD after surgical repair of AAD.

Methods: Plasma IL-6 was measured using electrochemiluminescence technology in patients preoperatively and 24 h, 48 h, and 72 h after surgical repair of acute type A aortic dissection. After the first three postoperative days, delirium was evaluated twice daily using the Confusion Assessment Method. ROC curves were used to evaluate the ability of IL-6 measurements to distinguish POD.

Results: The incidence of POD was 14.03% (31 of 221 patients). The patients in the POD group were significantly older than the patients in the non-POD group (56.48 ± 11.68 years vs 52.22 ± 10.50 years, P = 0.040). Plasma IL-6 concentrations were significantly higher in the POD group than in the non-POD group at three time points: preoperatively, after 24 h, and after 48 h. The AUC values corresponding to IL-6 preoperatively and 24 h after surgery were 0.73 and 0.72, respectively.

Conclusions: Cerebral dysfunction after the surgical repair of AAD shows elevated stress levels and inflammatory responses. Plasma IL-6 is a potential biomarker to predict the onset of POD in acute type A aortic dissection patients following surgical repair.
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http://dx.doi.org/10.1186/s13019-021-01529-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8161913PMC
May 2021

Skeletal muscle metastases of hepatocellular carcinoma: A case report and literature review.

World J Clin Cases 2021 May;9(14):3334-3341

Department of Ultrasound, Bethune First Hospital of Jilin University, Changchun 130000, Jilin Province, China.

Background: The metastasis of liver cancer to skeletal muscle is extremely rare compared to other sites. We herein report a case of rapidly developing skeletal metastases following liver transplantation due to primary liver cancer.

Case Summary: A 70-year-old male with underlying chronic hepatitis B virus infection was diagnosed with hepatocellular carcinoma (HCC), for which he underwent liver transplantation in 2014. Six years after receiving the transplant, pathological examination confirmed the presence of HCC without vascular invasion. He was admitted to the hospital with a rapidly growing mass on his right thigh. Ultrasound examination revealed a mixed echo mass in the lateral soft tissue of the middle part of the right femur. Magnetic resonance imaging showed heterogeneous iso-signal intensity on T1-weighted images and heterogeneous hyper-intensity on T2-weighted images compared to the surrounding muscles. Pathological examination of the ultrasound-guided needle biopsy specimen revealed that it was similar to the previously detected liver cancer; the diagnosis was metastasis of HCC. Surgical excision was performed. There were no other sites of metastasis, and the patient recovered well after surgery.

Conclusion: This report presents a rare case of skeletal metastasis following liver transplantation for HCC. The study suggests a possible role for skeletal muscle metastasis mechanisms, which should be the focus of future research.
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http://dx.doi.org/10.12998/wjcc.v9.i14.3334DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8107905PMC
May 2021

MiRNA-202-5p promotes Colorectal Carcinogenesis through suppression of PTEN.

J Cancer 2021 31;12(11):3154-3163. Epub 2021 Mar 31.

Department of Immunology, the school of Basic Medical Sciences, Anhui Medical University, Hefei, China, 230032.

Colorectal cancer (CRC) is still one of the leading causes of cancer-associated death in the modern society. The biological function of miR-202-5p for CRC development remains controversial, largely due to the fact that miR-202-5p can be tumor-suppressive or oncogenic in different contexts. Obtained results indicated that aberrant expression of miR-202-5p was observed in majority of human CRC samples and miR-202-5p was transcriptionally up-regulated by c-Myc. In addition, miR-202-5p functions to promote the activation of PI3K/Akt signaling pathway by directly suppressing PTEN. Silencing or enforced expression of miR-202-5p resulted in CRC cell proliferation inhibition and enhancement, respectively. Importantly, decreased PTEN level and increased phosphorylation of Akt were frequently associated with elevated miR-202-5p expression in colorectal cancer tissues. Increased miR-202-5p expression may serve as a tumor promoter by directly targeting PTEN in colorectal cancer.
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http://dx.doi.org/10.7150/jca.56186DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8100819PMC
March 2021

Whole-Exome Sequencing Identifies a Novel Mutation in a Chinese Family with Atrioventricular Block.

Biomed Res Int 2021 17;2021:9247541. Epub 2021 Apr 17.

Department of Cell Biology, School of Life Sciences, Central South University, Changsha 410013, China.

Atrioventricular block (AVB) is a leading cause of sudden cardiac death, and most of AVB cases are presented as autosomal dominant. The electrocardiogram of AVB patients presents an abnormal progressive cardiac conduction disorder between atria and ventricles. () is a nonselective Ca-activated cation channel gene defined as a novel disease-causing gene of AVB. So far, 47 mutations of have been recorded in Human Gene Mutation Database. The aim of this study was to explore the relationship between mutation and pathogenesis of AVB. We investigated a Chinese family with AVB by whole-exome sequencing. An arrhythmia-related gene filtering strategy was used to analyze the disease-causing mutations. Three different bioinformatics programs were used to predict the effects of the mutation result. A novel mutation of was identified (c.2455C>T/p.R819C) and cosegregated in the affected family members. The three bioinformatics programs predicted that the novel mutation may lead to damage. Our study will contribute to expand the spectrum of mutations and supply accurate genetic testing information for further research and the clinical therapy of AVB.
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http://dx.doi.org/10.1155/2021/9247541DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8075657PMC
May 2021

How to perform shear wave elastography. Part I.

Med Ultrason 2021 May 4. Epub 2021 May 4.

Department Allgemeine Innere Medizin (DAIM), Kliniken Hirslanden Beau Site, Salem und Permancence, Bern, Switzerland.

We recently introduced a series of papers describing how to do certain techniques. This article is the first part of a review of shear wave elastography (SWE). It reports the principles and interpretation of the technique and describes how to optimize it. Normal values, pitfalls and artefacts for the examination of liver, breast. thyroid and salivary gland with shear wave elastography are presented. The manuscript provides specific tips for applying SWE as part of a diagnostic US examination.
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http://dx.doi.org/10.11152/mu-3217DOI Listing
May 2021

"Knobology" in Doppler Ultrasound.

Med Ultrason 2021 May 4. Epub 2021 May 4.

Department Allgemeine Innere Medizin (DAIM) Kliniken Hirslanden Beau Site, Salem und Permanence, Bern, Switzerland.

Ultrasonography is a ubiquitous and indispensable diagnostic and therapeutic tool in medicine. Due to modern equipment and automatic image optimization, nowadays the introduction of ultrasound imaging requires only little technical and physical knowledge. However, profound knowledge of the device function repertoire and underlying mechanisms are essential foroptimal image adjustment and documentation. From a medical as well as an aesthetic point of view, the goal should always be to achieve the best possible image quality. This article provides an overview of handling of ultrasound systems, fundamental adjustments and their optimization in Doppler ultrasound.
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http://dx.doi.org/10.11152/mu-3216DOI Listing
May 2021

Characterization of lung ultrasound imaging in preterm infants with bronchopulmonary dysplasia.

Clin Hemorheol Microcirc 2021 Apr 28. Epub 2021 Apr 28.

Department of Neonatology, Children's Hospital of Fudan University, Shanghai, China.

Background: Lung ultrasound (LUS) is a bedside technique that can be used on diagnosis and follow-up of neonatal respiratory diseases. However, there are rare reports on the ultrasound features of bronchopulmonary dysplasia (BPD) which is one of the most common chronic lung diseases in preterm infants.

Objective: To describe the ultrasound features of different BPD levels, and to investigate the value of ultrasound in evaluating moderate-to-severe BPD.

Methods: In this prospective cohort study, newborns of less than 37 weeks' gestational age in neonatal intensive care unit (NICU) were included. The LUS characteristics including pleural line, alveolar-interstitial syndrome (AIS), retrodiaphragmatic hyperechogenicity and diaphragmatic morphology were observed and recorded. The reliability of LUS in evaluating moderate and severe BPD were compared and calculated.

Results: A total of 108 infants were enrolled in our study: 39, 24, 29, 16 infants had non, mild, moderate and severe BPD. The median(IQR) pleura thickness in the moderate-to-severe BPD group was 1.7(1.6-1.85) mm, which was thicker than that in the none-to-mild BPD infants (P <  0.001), meanwhile the proportions of rough pleural lines, diffuse AIS, retrodiaphragmatic hyperechogenicity, small cysts above the diaphragm and rough diaphragm in the moderate-to-severe BPD group were also higher than those in none-to-mild BPD group (86.7% vs 36.5, 57.8% vs 7.9%, 37.8% vs 0, 33.3% vs 0, P <  0.001). In evaluating moderate-to-severe BPD, rough pleura had 91.1% (95% confidence interval [CI]: 0.793-0.965) in sensitivity, 91.3% (95% CI: 0.797-0.966) in negative predictive value (NPV), and 66.7% (95% CI: 0.544-0.771) in specificity. Small cysts had 100% (95% CI: 0.941-1) in specificity, 100% (95% CI: 0.816-1) in PPV, and 37.8% in sensitivity (95% CI: 0.251-0.524). Rough diaphragm had 100% (95% CI: 0.943-1) in sensitivity, 100% (95% CI: 0.796-1) in PPV and 33.3% (95% CI: 0.211-0.478) in specificity.

Conclusions: Depending on its unique advantages such as convenient, no radiation and repeatable, LUS is a valuable imaging method in assessing the severity of BPD, especially in moderate and severe BPD.
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http://dx.doi.org/10.3233/CH-211132DOI Listing
April 2021

Dual-frequency Doppler velocimeter based on delay interferometric optical phase-locking.

Opt Lett 2021 May;46(9):2103-2106

We present a dual-frequency laser Doppler velocimeter (DF-LDV) relying on a DF laser source (DFLS) generated by optical phase-locking two individual lasers to a common unbalanced Mach-Zehnder interferometer, which allows achieving high stability regardless of the DF separation of the lasers. This DFLS is evaluated using an optical frequency comb, testifying to the generation of DFLS with large DF separation up to terahertz with flexible tunability and high stability. Demonstration of DF-LDV using the DFLS of ${\sim}1.024\; {\rm THz}$ separation has achieved $1.62 \times {10^{- 2}}$ mm/s velocity resolution even for a slow velocity of $1.8\; {\rm mm}/{\rm s}$ in a mere 5 s acquisition time, confirming the high resolution and efficient speckle noise suppression enabled by the proposed DF-LDV. Featuring high precision, flexibility, and robustness, this method is particularly attractive from the practical point of view.
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http://dx.doi.org/10.1364/OL.420402DOI Listing
May 2021

Post-Translational Regulations of Foxp3 in Treg Cells and Their Therapeutic Applications.

Front Immunol 2021 12;12:626172. Epub 2021 Apr 12.

Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Science, Shenzhen, China.

Regulatory T (Treg) cells are indispensable for immune homeostasis due to their roles in peripheral tolerance. As the master transcription factor of Treg cells, Forkhead box P3 (Foxp3) strongly regulates Treg function and plasticity. Because of this, considerable research efforts have been directed at elucidating the mechanisms controlling Foxp3 and its co-regulators. Such work is not only advancing our understanding on Treg cell biology, but also uncovering novel targets for clinical manipulation in autoimmune diseases, organ transplantation, and tumor therapies. Recently, many studies have explored the post-translational regulation of Foxp3, which have shown that acetylation, phosphorylation, glycosylation, methylation, and ubiquitination are important for determining Foxp3 function and plasticity. Additionally, some of these targets have been implicated to have great therapeutic values. In this review, we will discuss emerging evidence of post-translational regulations on Foxp3 in Treg cells and their exciting therapeutic applications.
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http://dx.doi.org/10.3389/fimmu.2021.626172DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8071870PMC
April 2021

Olfactory Impairment Among Rural-Dwelling Chinese Older Adults: Prevalence and Associations With Demographic, Lifestyle, and Clinical Factors.

Front Aging Neurosci 2021 12;13:621619. Epub 2021 Apr 12.

Department of Neurology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.

Olfactory impairment (OI) refers to decreased (hyposmia) or absent (anosmia) ability to smell. We sought to estimate the prevalence and correlates of OI among rural-dwelling Chinese older adults. This population-based cross-sectional analysis included 4,514 participants (age ≥65 years; 56.7% women) from the Multidomain Interventions to Delay Dementia and Disability in Rural China (MIND-China). The 16-item Sniffin' Sticks identification test (SSIT) was used to assess olfactory function. Olfactory impairment was defined as the SSIT score ≤10, hyposmia as SSIT score of 8-10, and anosmia as SSIT score <8. Multivariable logistic regression models were used to examine factors associated with OI. The overall prevalence was 67.7% for OI, 35.3% for hyposmia, and 32.5% for anosmia. The prevalence increased with age for OI and anosmia, but not for hyposmia. The multivariable-adjusted odds ratio (OR) of OI was 2.10 (95% CI 1.69-2.61) for illiteracy and 1.41 (1.18-1.70) for elementary school (vs. middle school or above), 1.30 (1.01-1.67) for current smoking (vs. never smoking), 0.86 (0.74-0.99) for overweight and 0.73 (0.61-0.87) for obesity (vs. normal weight), 4.21 (2.23-7.94) for dementia, 1.68 (1.23-2.30) for head injury, and 1.44 (1.14-1.83) for sinonasal disease. Illiteracy in combination with either male sex or diabetes was significantly associated with an over two-fold increased OR of OI ( for interactions <0.05). Olfactory impairment is highly prevalent that affects over two-thirds of rural-dwelling older adults in China. OI is correlated with illiteracy, current smoking, dementia, head injury, and sinonasal disease, but negatively associated with overweight or obesity. Olfactory impairment as a potential clinical marker of neurodegenerative disorders among older adults deserves further investigation.
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http://dx.doi.org/10.3389/fnagi.2021.621619DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072018PMC
April 2021

Colonic epithelial adaptation to EGFR-independent growth induces chromosomal instability and is accelerated by prior injury.

Neoplasia 2021 May 24;23(5):488-501. Epub 2021 Apr 24.

Department of Pathology, Division of GI/Liver Pathology, Johns Hopkins University School of Medicine, Baltimore, MD USA; Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD USA. Electronic address:

Although much is known about the gene mutations required to drive colorectal cancer (CRC) initiation, the tissue-specific selective microenvironments in which neoplasia arises remains less characterized. Here, we determined whether modulation of intestinal stem cell niche morphogens alone can exert a neoplasia-relevant selective pressure on normal colonic epithelium. Using adult stem cell-derived murine colonic epithelial organoids (colonoids), we employed a strategy of sustained withdrawal of epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) inhibition to select for and expand survivors. EGFR-signaling-independent (iEGFR) colonoids emerged over rounds of selection and expansion. Colonoids derived from a mouse model of chronic mucosal injury showed an enhanced ability to adapt to EGFR inhibition. Whole-exome and transcriptomic analyses of iEGFR colonoids demonstrated acquisition of deleterious mutations and altered expression of genes implicated in EGF signaling, pyroptosis, and CRC. iEGFR colonoids acquired dysplasia-associated cytomorphologic changes, an increased proliferative rate, and the ability to survive independently of other required niche factors. These changes were accompanied by emergence of aneuploidy and chromosomal instability; further, the observed mitotic segregation errors were significantly associated with loss of interkinetic nuclear migration, a fundamental and dynamic process underlying intestinal epithelial homeostasis. This study provides key evidence that chromosomal instability and other phenotypes associated with neoplasia can be induced ex vivo via adaptation to EGF withdrawal in normal and stably euploid colonic epithelium, without introducing cancer-associated driver mutations. In addition, prior mucosal injury accelerates this evolutionary process.
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http://dx.doi.org/10.1016/j.neo.2021.03.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8099723PMC
May 2021

Teaching NeuroImages: Parkinsonism Presenting With Watershed Pattern Lesions.

Neurology 2021 Apr 26. Epub 2021 Apr 26.

Department of Neurology, Huashan Hospital, Fudan University

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http://dx.doi.org/10.1212/WNL.0000000000012056DOI Listing
April 2021

Structure optimization of gasket based on orthogonal experiment and NSGA-II.

Sci Prog 2021 Apr-Jun;104(2):368504211011347

Vehicle Engineering Department, Army Academy of Armored Forces, Beijing, China.

With the aim of enhancing both reliability and fatigue life of gasket, this study combines finite element analysis, orthogonal experimental design, dynamically-guided multi-objective optimization, and the non-dominated sorting genetic algorithm with elitist strategy to optimize the geometric parameters of the cylinder gasket. The finite element method was used to analyze the temperature field, thermal-mechanical coupling stress field, and deformation of cylinder gasket. The calculation results were experimentally validated by measured temperature data, and comparison results show that the maximum error between calculated value and experiment value is 7.1%, which is acceptable in engineering problems. Based on above results and orthogonal experiment design method, the effects of five factors, including diameter of combustion chamber circle, diameter of coolant flow hole, length of the insulation zone between third and fourth cylinders, thickness of gasket, and bolt preload, on three indexes: temperature, stress, and deformation of gasket, were examined in depth. Through the variance analysis of the results, three important factors were identified to proceed later calculation. The dynamically guided multi-objective optimization strategy and the non-dominated sorting genetic algorithm were effectively used and combined to determine the optimal geometric parameters of cylinder gasket. Furthermore, calculation results suggest that temperature, stress, and deformation of the optimized cylinder gasket have been improved by 27.88 K, 16.84 MPa, and 0.0542 mm, respectively when compared with the origin object, which shows the excellent performance of gasket optimization and effectiveness of the proposed optimization strategy.
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http://dx.doi.org/10.1177/00368504211011347DOI Listing
April 2021

[Correlation analysis between degenerative spondylolisthesis and T2WI hyperintensity on MRI of interspinous ligament].

Zhongguo Gu Shang 2021 Apr;34(4):333-6

Department of Radiology, the First People's Hospital of Xiaoshan, Hangzhou 311200, Zhejiang, China.

Objective: To explore the relationship between lumbar degenerative spondylolisthesis and T2WI high signal in the interspinous ligament in MRI in order to improve the understanding of the signal changes of the interspinous ligament.

Methods: The clinical data of 43 patients with clinically diagnosed lumbar degenerative spondylolisthesis were collected from March 2018 to March 2020, there were 19 males and 24 females, aged 50 to 92 years with an average of 69 years old. Using picture archiving and communication systems (PACS) to access images and record the distribution and incidence of T2WI high signal in the interspinous ligament between the slipped and non-slipped segments. Using Spearman correlation analysis to explore the relationshipbetween the T2WI high signal of the interspinous ligament and the degree of lumbar spondylolisthesis.

Results: Except for 8 ligaments that were not included in the statistical results due to poor image quality, 43 patients with a total of 207 lumbar vertebrae and interspinous ligaments were included in the study. According to the Meyerding classification method, 43 patients had a total of 48 segments with spondylolisthesis, 41 segments in grade Ⅰ and 7 segments in grade Ⅱ. There were 30 cases of MRI T2WI high signal in the interspinous ligament corresponding to spondylolisthesis segment, including 3 cases on L segment, 3 cases on L segment, 20 cases on L segment, and 4 cases on LS segment. And there were 53 cases of MRI T2WI hyperintensity in 159 non slipped interspinous ligaments, of which 6 cases were at L, 6 were at L, 13 were on L, 7 were on L, and 21 were on LS. Compared with the non slipped segment, the incidence of high signal on the T2WI of the interspinous ligament was 62.5% and 33.3%, respectively, and the difference was statistically significant (= 13.06, <0.05). Spearman correlation analysis showed that the presence of T2WI hyperintensity of interspinous ligament was positively correlated with the degree of lumbar spondylolisthesis (=0.264, <0.05).

Conclusion: In patients with degenerative lumbar spondylolisthesis, the MRI T2WI hyperintensity is more common in the interspinous ligament. The occurrence of T2WI high signal is positively correlated with the degree of spondylolisthesis, which should be payed enough attention in imaging diagnosis.
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http://dx.doi.org/10.12200/j.issn.1003-0034.2021.04.007DOI Listing
April 2021

Surgery at early versus late for intermittent exotropia: a Meta-analysis and systematic review.

Int J Ophthalmol 2021 18;14(4):582-588. Epub 2021 Apr 18.

Tianjin Eye Hospital, Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin Eye Institute, Clinical College of Ophthalmology Tianjin Medical University, Tianjin 300020, China.

Aim: To compare the outcomes between early surgery and late surgery for intermittent exotropia (IXT) with a Meta-analysis.

Methods: Scientific databases including PubMed, Embase, Web of Science, Cochrane and China National Knowledge Infrastructure were searched prior to December 16, 2019. From this broad database search, we performed some Meta-analysis including eleven independent studies, to further evaluate the outcome(s) when comparing early versus late surgery for IXT. The boundaries between early and late surgery and the surgery methods were not inconsistent, so subgroup analyses were conducted by different boundaries of age at surgery and different surgical approaches. The pooled odds ratios (ORs) and the 95% confidence interval (CI) were estimated according to the random-effects model for high heterogeneity between studies.

Results: Eleven retrospective studies were included in this Meta-analysis. No significant difference between early and late surgery was observed for IXT patients (OR=0.88, 95%CI 0.53-1.44, =0.61; OR=1.48, 95%CI 0.94-2.31, =0.09). However, sensitivity analysis performed by sequentially omitting individual studies showed that the final follow-up result was not stable. Subgroup analyses revealed that an earlier surgical procedure could lead to a better outcome in the 4-year boundary subgroup as well as the bilateral lateral rectus recession (BLR) subgroup for the final follow-up (OR=2.64, 95%CI 1.57-4.44, =0.00; OR=2.25, 95%CI 1.36-3.74, =0.00).

Conclusion: Early surgery for IXT provides a better long term follow-up outcome when patients are younger than 4 years old or choose the BLR surgical method.
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http://dx.doi.org/10.18240/ijo.2021.04.16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8025175PMC
April 2021

Neuromodulation-Based Stem Cell Therapy in Brain Repair: Recent Advances and Future Perspectives.

Neurosci Bull 2021 May 19;37(5):735-745. Epub 2021 Apr 19.

State Key Laboratory of Brain and Cognitive Sciences, the University of Hong Kong, Jiulong, Hong Kong SAR, China.

Stem cell transplantation holds a promising future for central nervous system repair. Current challenges, however, include spatially and temporally defined cell differentiation and maturation, plus the integration of transplanted neural cells into host circuits. Here we discuss the potential advantages of neuromodulation-based stem cell therapy, which can improve the viability and proliferation of stem cells, guide migration to the repair site, orchestrate the differentiation process, and promote the integration of neural circuitry for functional rehabilitation. All these advantages of neuromodulation make it one potentially valuable tool for further improving the efficiency of stem cell transplantation.
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http://dx.doi.org/10.1007/s12264-021-00667-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8099989PMC
May 2021

Functional NMDA receptors are expressed by human pulmonary artery smooth muscle cells.

Sci Rep 2021 Apr 15;11(1):8205. Epub 2021 Apr 15.

Department of Pediatrics and Neurology, Perelman School of Medicine, The Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, PA, 19104, USA.

N-methyl-D-aspartate (NMDA) receptors are widely expressed in the central nervous system. However, their presence and function at extraneuronal sites is less well characterized. In the present study, we examined the expression of NMDA receptor subunit mRNA and protein in human pulmonary artery (HPA) by quantitative polymerase chain reaction (PCR), immunohistochemistry and immunoblotting. We demonstrate that both GluN1 and GluN2 subunit mRNAs are expressed in HPA. In addition, GluN1 and GluN2 (A-D) subunit proteins are expressed by human pulmonary artery smooth muscle cells (HPASMCs) in vitro and in vivo. These subunits localize on the surface of HPASMCs and form functional ion channels as evidenced by whole-cell patch-clamp electrophysiology and reduced phenylephrine-induced contractile responsiveness of human pulmonary artery by the NMDA receptor antagonist MK801 under hypoxic condition. HPASMCs also express high levels of serine racemase and vesicular glutamate transporter 1, suggesting a potential source of endogenous agonists for NMDA receptor activation. Our findings show HPASMCs express functional NMDA receptors in line with their effect on pulmonary vasoconstriction, and thereby suggest a novel therapeutic target for pharmacological modulations in settings associated with pulmonary vascular dysfunction.
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http://dx.doi.org/10.1038/s41598-021-87667-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8050278PMC
April 2021

EZH2-Mediated microRNA-375 Upregulation Promotes Progression of Breast Cancer the Inhibition of FOXO1 and the p53 Signaling Pathway.

Front Genet 2021 29;12:633756. Epub 2021 Mar 29.

Department of Breast Surgery, The First Hospital of Jilin University, Changchun, China.

Breast cancer (BC) is the most common gynecologic tumor worldwide where aberrant expression of microRNAs (miRNAs) is frequently involved. Here, we evaluated the function of miR-375 on BC development and the molecules implicated. Differentially expressed genes between tumor and paired normal tissues from BC patients were screened out by microarray analyses. miR-375 was abundantly expressed in BC tissues and cells, and it was correlated with the poor prognosis of patients. Downregulation of miR-375 was introduced into BC cell lines MCF-7 and HCC1954, after which the viability, colony formation, migration, and invasion were suppressed, while the apoptosis of cells was increased, and the xenograft tumors in nude mice were reduced as well. EZH2 increased methylation and phosphorylation of signal transducer and activator of transcription 3 (STAT3) and increased transcription activity of miR-375, while miR-375 directly targeted FOXO1. Either overexpression of EZH2 or downregulation of FOXO1 blocked the functions of anti-miR-375 in cells and animals. FOXO1 was found as an activator of the p53 signaling pathway. This study showed that miR-375 is an important oncogene in BC. EZH2 is an upstream regulator of miR-375 through mediating the methylation of STAT3, while FOXO1 is a downstream target mRNA of miR-375 that activates the p53 signaling pathway to suppress BC development.
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http://dx.doi.org/10.3389/fgene.2021.633756DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8041054PMC
March 2021

Peroxiredoxin alleviates the fitness costs of imidacloprid resistance in an insect pest of rice.

PLoS Biol 2021 Apr 12;19(4):e3001190. Epub 2021 Apr 12.

State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.

Chemical insecticides have been heavily employed as the most effective measure for control of agricultural and medical pests, but evolution of resistance by pests threatens the sustainability of this approach. Resistance-conferring mutations sometimes impose fitness costs, which may drive subsequent evolution of compensatory modifier mutations alleviating the costs of resistance. However, how modifier mutations evolve and function to overcome the fitness cost of resistance still remains unknown. Here we show that overexpression of P450s not only confers imidacloprid resistance in the brown planthopper, Nilaparvata lugens, the most voracious pest of rice, but also leads to elevated production of reactive oxygen species (ROS) through metabolism of imidacloprid and host plant compounds. The inevitable production of ROS incurs a fitness cost to the pest, which drives the increase or fixation of the compensatory modifier allele T65549 within the promoter region of N. lugens peroxiredoxin (NlPrx) in the pest populations. T65549 allele in turn upregulates the expression of NlPrx and thus increases resistant individuals' ability to clear the cost-incurring ROS of any source. The frequent involvement of P450s in insecticide resistance and their capacity to produce ROS while metabolizing their substrates suggest that peroxiredoxin or other ROS-scavenging genes may be among the common modifier genes for alleviating the fitness cost of insecticide resistance.
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http://dx.doi.org/10.1371/journal.pbio.3001190DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8062100PMC
April 2021

Low vs standardized dose anticoagulation regimens for extracorporeal membrane oxygenation: A meta-analysis.

PLoS One 2021 8;16(4):e0249854. Epub 2021 Apr 8.

Department of Cardiac Surgery, Fujian Medical University Union Hospital, Fujian, China.

Background: To compare the safety and efficacy of low-dose anticoagulation (LA) with that of standardized dose anticoagulation (SA) for patients supported with extracorporeal membrane oxygenation (ECMO).

Methods: PubMed, MEDLINE, the Cochrane Library, and Web of Science were screened for original articles. Screening was performed using predefined search terms to identify cohort studies reporting the comparison of LA with SA in patients supported with ECMO from Nov 1990 to Jun 2020. The effect size was determined by the odds ratio (OR) with the 95% confidence interval (CI).

Results: An analysis of 7 studies including a total of 553 patients was performed. LA (Low-heparin group) was administered to 255 patients, whereas the other 298 patients received SA (Full-heparin group). The incidence of gastrointestinal tract hemorrhage (OR 0.36, 95% CI 0.20-0.64) and surgical site hemorrhage (OR 0.43, 95% CI 0.20-0.94) were significantly lower in patients who underwent LA compared with that in those who underwent SA. The rates of hospital mortality (OR 0.81, 95% CI 0.42-1.56), successfully weaning off of ECMO (OR 0.80, 95% CI 0.30-2.14), pulmonary embolism (OR 0.79, 95% CI 0.24-2.65), intracardiac thrombus (OR 0.34, 95% CI 0.09-1.30), intracranial hemorrhage (OR 0.62, 95% CI 0.22-1.74), and pulmonary hemorrhage (OR 0.77, 95% CI 0.30-1.93) were similar between the two groups.

Conclusions: This meta-analysis confirms that LA is a feasible and safe anticoagulation strategy in patients supported by ECMO. Future studies should focus on the long-term benefits of LA compared with SA.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0249854PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8031334PMC
April 2021

Characteristics of fixation patterns and their relationship with visual function of patients with idiopathic macular holes after vitrectomy.

Sci Rep 2021 Apr 7;11(1):7658. Epub 2021 Apr 7.

Tianjin Eye Hospital, Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin Eye Institute, Nankai University affiliated Eye Hospital, Clinical College of Ophthalmology, Tianjin Medical University, Gansu Road 4, Heping District, Tianjin, 300020, China.

To analyze the relationships between the fixation location and the visual function of idiopathic macular hole (IMH) patients with macular integrity assessment (MAIA) examination preoperatively and 3 months postoperatively. This was a retrospective case analysis. Forty-three eyes of 43 patients diagnosed with IMH were included in this study. The best corrected visual acuity (BCVA) assessments, optical coherence tomography (OCT) and MAIA examinations were performed before surgery and 1 week, 1 month and 3 months after surgery. The relationships between MAIA parameters and visual acuity were assessed by correlation analysis. Grouping by fixation location with the foveola (2°) as the centre, the locations could be divided into five groups, including foveolar, temporal, nasal, inferior and superior fixation. The mean macular sensitivity (MMS) of the macular area was correlated with the BCVA in the IMH patients before and 3 months after surgery (before surgery P = 0.00, after surgery P = 0.00). The MMS could be used as a good indicator for evaluating visual function in IMH patients. There was a significant difference in fixation location before and after the operation (P = 0.01). The preoperative fixation location of IMH patients was mainly in the superior area, while postoperatively moved to the foveola and nasal areas. Paying attention to the changes of fixation locations in IMH patients may provide new clues for further improving postoperative visual function.
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http://dx.doi.org/10.1038/s41598-021-87286-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8027455PMC
April 2021

Creep-Fatigue Experiment and Life Prediction Study of Piston 2A80 Aluminum Alloy.

Materials (Basel) 2021 Mar 13;14(6). Epub 2021 Mar 13.

Department of Weapon and Control, Army Academy of Armored Forces, Beijing 100072, China.

In order to improve the reliability and service life of vehicle and diesel engine, the fatigue life prediction of the piston in a heavy diesel engine was studied by finite element analysis of piston, experiment data of aluminum alloy, fatigue life model based on energy dissipation criteria, and machine learning algorithm. First, the finite element method was used to calculate and analyze the temperature field, thermal stress field, and thermal-mechanical coupling stress field of the piston, and determine the area of heavy thermal and mechanical load that will affect the fatigue life of the piston. Second, based on the results of finite element calculation, the creep-fatigue experiment of 2A80 aluminum alloy was carried out, and the cyclic response characteristics of the material under different loading conditions were obtained. Third, the fatigue life prediction models based on energy dissipation criterion and twin support vector regression are proposed. Then, the accuracy of the two models was verified using experiment data. The results show that the model based on the twin support vector regression is more accurate for predicting the material properties of aluminum alloy. Based on the established life prediction model, the fatigue life of pistons under actual service conditions is predicted. The calculation results show that the minimum fatigue life of the piston under plain condition is 2113.60 h, and the fatigue life under 5000 m altitude condition is 1425.70 h.
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http://dx.doi.org/10.3390/ma14061403DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8001697PMC
March 2021

Feprazone Ameliorates TNF-α-Induced Loss of Aggrecan via Inhibition of the SOX-4/ADAMTS-5 Signaling Pathway.

ACS Omega 2021 Mar 12;6(11):7638-7645. Epub 2021 Mar 12.

Department of Joint and orthopedics, Traditional Chinese Medicine Hospital of Kunshan, Suzhou, Jiangsu 215300, China.

: Arthritis is a cartilage degenerative disease that is mainly induced by the degradation of the cartilage extracellular matrix (ECM), which is found to be regulated by the expression level of a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMT-5), an enzyme degrading Aggrecans in the ECM. Feprazone is a classic nonsteroidal anti-inflammatory drug with promising efficacy in arthritis. The present study aims to investigate the protective effect of Feprazone on the degraded Aggrecan in the human chondrocytes induced with tumor necrosis factor-α (TNF-α) and to clarify the underlying mechanism. : To investigate the effect of Feprazone, the CHON-001 chondrocytes were stimulated with TNF-α (10 ng/mL) in the presence or absence of Feprazone (3, 6 μM) for 24 h. Mitochondrial membrane potential was evaluated using the Rhodamine 123 assay. The gene expressions of interleukin-1β (IL-1β), interleukin-8 (IL-8), monocyte chemotactic protein 1 (MCP-1), and ADAMTS-5 in the treated chondrocytes were detected using real-time quantitative polymerase chain reaction (qRT-PCR), and the protein levels of these targets were determined using enzyme-linked immunosorbent assay (ELISA). SOX-4 was knocked down by transfecting the siRNA into the chondrocytes. Western blot analysis was utilized to evaluate the expression levels of SOX-4, Aggrecan, and protein kinase C (PKCα). : First, the reduced mitochondrial membrane potential (ΔΨ) and secretion of proinflammatory factors (IL-1β, IL-8, and MCP-1) induced by TNF-α were significantly reversed by treatment with Feprazone. Second, the expression of Aggrecan was significantly decreased by stimulation with TNF-α via upregulation of ADAMTS-5 but was dramatically reversed by the introduction of Feprazone. Third, we found that TNF-α elevated the expression of ADAMTS-5 by upregulating SOX-4, which was observed to be related to the activation of PKCα. Lastly, the elevated expression of SOX-4 induced by TNF-α was significantly reversed by Feprazone. : Feprazone might ameliorate TNF-α-induced loss of Aggrecan via the inhibition of the SOX-4/ADAMTS-5 signaling pathway.
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http://dx.doi.org/10.1021/acsomega.0c06212DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7992146PMC
March 2021

Biopsy-proven liver cirrhosis in young children: A 10-year cohort study.

J Viral Hepat 2021 Jun 5;28(6):959-963. Epub 2021 Apr 5.

The Fifth Medical Center (formerly Beijing 302 Hospital), Chinese PLA General Hospital, Beijing, China.

Young children with liver cirrhosis have a significantly high risk of mortality. However, there are few studies regarding early childhood-onset cirrhosis. This study aims to explore the causes, clinical findings and prognosis of biopsy-proven cirrhosis in infants, toddlers and preschoolers. We enroled young children with biopsy-proven cirrhosis from January 2010. Till January 2020, the study has been going on for 10 years. A total of 139 cirrhotic children were enrolled, including 87 boys and 52 girls. The median age at initially histological diagnosis of cirrhosis was 2 years old (range: 1 month-6 years). Sixty-two patients reported yellowish discoloration of sclera and/or skin as an initial symptom. Ninety-three patients had definite aetiologies while 46 had indeterminate causes. Among the confirmed cases, 31 had hepatitis B virus (HBV) infection, accounting for 33.3%. Subsequently, glycogen storage disease was diagnosed in 16 cases and Wilson disease in 14 cases. In these patients with HBV infection, nine finally achieved hepatitis B surface antigen (HBsAg) loss (29.0%) after effective antiviral therapy during the follow-up. Logistic regression revealed that baseline alanine aminotransferase (odds ratio 1.008, p = 0.028) was the independent predictor of HBsAg loss. Furthermore, one patient who underwent second biopsies showed histological reverse. HBV infection is an important cause of paediatric cirrhosis in our study. The pathogenesis of HBV-related cirrhosis in early childhood deserves further studies.
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http://dx.doi.org/10.1111/jvh.13501DOI Listing
June 2021

High-Frame Rate Vector Flow Imaging Technique: Initial Application in Evaluating the Hemodynamic Changes of Carotid Stenosis Caused by Atherosclerosis.

Front Cardiovasc Med 2021 8;8:617391. Epub 2021 Mar 8.

Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China.

To investigate the value of high-frame rate vector flow imaging technique (V flow) in evaluating the hemodynamic changes of carotid stenosis caused by atherosclerotic plaques. In this prospective study, patients with stenosis rate (diameter) ≥30% caused by carotid atherosclerotic plaques were included. Degrees of carotid stenosis were graded according to North American Symptomatic Carotid Endarterectomy Trial criteria: moderate (30-69%) or severe (70-99%). Mindray Resona 7s ultrasound machine with a linear array transducer (3-11 MHz) was used for ultrasound examinations. The mean WSS value of carotid arteries was measured at the proximal, narrowest region and distal of carotid stenosis. The mean WSS values were correlated with peak systolic velocity (PSV) measured by color Doppler flow imaging and stenosis degree detected by digital subtraction angiography (DSA). The vector arrows and flow streamline detected by V flow dynamic imaging were analyzed. Imaging findings of DSA in carotid arteries were used as the gold standard. Finally, 51 patients were included. V flow measurements were performed successfully in 17 patients (100%) with moderate-grade stenosis and in 30 patients (88.2%) with severe-grade stenosis. Dynamic V flow imaging showed yellow or red vectors at the stenotic segment, indicating fast speed blood flow (up to 260.92 cm/s). Changes of streamlines were detected in the stenotic segment. The mean WSS value measured at the narrowest region of the carotid artery had a moderately positive correlation with stenosis degree ( = 0.58, < 0.05) and PSV value ( = 0.54, < 0.05), respectively. Significant difference was detected in mean WSS value at the narrowest region of the carotid artery between severe carotid stenosis (1.47 ± 0.97 Pa) and moderate carotid stenosis (0.96 ± 0.44 Pa) ( < 0.05). The hemodynamic changes detected by V flow of the carotid stenosis might be a potential non-invasive imaging tool for assessing the degree of carotid stenosis.
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http://dx.doi.org/10.3389/fcvm.2021.617391DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7982422PMC
March 2021

Optical linear frequency sweep based on a mode-spacing swept comb and multi-loop phase-locking for FMCW interferometry.

Opt Express 2021 Jan;29(2):604-614

We report on the generation of a highly coherent broadband optical linear frequency sweep (LFS) using mode-spacing swept comb and multi-loop composite optical phase-locked loop (OPLL). We exploit a specially designed agile opto-electronic frequency comb as a sweeping reference, whose mode-spacing is capable of arbitrary frequency sweep while preserving a stable phase and power distribution per mode. By locking a continuous-wave (CW) laser to any of its modes using composite OPLL with a large loop bandwidth, it allows the extraction of the optical LFS at high-order modes in a coherent manner with a multiplied sweep range and rate. With such capability, only intermediate frequency LFS with smaller bandwidth is required to yield a broadband LFS while inheriting the coherence and precision from the comb. We achieve optical LFS of 60 GHz at 6 THz/s sweep rate with a nine-folded sweep bandwidth of the driving signal. Fourier transform-limited spatial resolution at more than 80 times of the intrinsic coherence length of the CW laser is demonstrated in an OFMCW interferometry, verifying the high coherence with more than 4 orders of magnitude improvement in spatial resolution. The characteristics in terms of agility, coherence, and precision are discussed together with the potential limitations. The proposed method is capable of generating arbitrary frequency-modulated optical waveforms with a multiplied bandwidth, showing attractive potential in future metrology applications.
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http://dx.doi.org/10.1364/OE.410405DOI Listing
January 2021