Publications by authors named "H S Chen"

61,391 Publications

Genetics and therapy for pediatric eye diseases.

EBioMedicine 2021 May 7;67:103360. Epub 2021 May 7.

Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, MSC0610, 6 Center Drive, Bethesda, MD 20892 USA. Electronic address:

Ocular morphogenesis in vertebrates is a highly organized process, orchestrated largely by intrinsic genetic programs that exhibit stringent spatiotemporal control. Alternations in these genetic instructions can lead to hereditary or nonhereditary congenital disorders, a major cause of childhood visual impairment, and contribute to common late-onset blinding diseases. Currently, limited treatment options exist for clinical phenotypes involving eye development. This review summarizes recent advances in our understanding of early-onset ocular disorders and highlights genetic complexities in development and diseases, specifically focusing on coloboma, congenital glaucoma and Leber congenital amaurosis. We also discuss innovative paradigms for potential therapeutic modalities.
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http://dx.doi.org/10.1016/j.ebiom.2021.103360DOI Listing
May 2021

Selenium nanoparticles ameliorate Brassica napus L. cadmium toxicity by inhibiting the respiratory burst and scavenging reactive oxygen species.

J Hazard Mater 2021 Apr 16;417:125900. Epub 2021 Apr 16.

Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China. Electronic address:

Cadmium (Cd) is a widely distributed soil contaminant which induces oxidative damage and is therefore toxic to plants. Although selenium oxyanions such as selenite (SeO) and selenate (SeO) can alleviate Cd stress to plants, it is not known whether selenium nanoparticles (SeNPs) are able to do the same. The present study demonstrated the positive impact of both SeNPs and SeO on Brassica napus L. growth under conditions of Cd stress. Underlying mechanisms were elucidated using an oxidative stress detection assay, whole-genome RNA sequencing, and RT-qPCR. Application of selenium, especially in the form of SeNPs, decreased Cd-induced reactive oxygen species production by inhibiting the expression of NADPH oxidases (BnaRBOHC, BnaRBOHD1, and BnaRBOHF1) and glycolate oxidase (BnaGLO), thereby decreasing oxidative protein and membrane lipid damage. In addition, SeNPs improved resistance to Cd stress by decreasing Cd accumulation, maintaining intracellular calcium homeostasis, promoting disulfide bond formation, and restoring the waxy outer layer of the leaf surface. Although both forms of selenium decreased Cd toxicity, the beneficial concentration range was more extensive for SeNPs than for SeO.
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http://dx.doi.org/10.1016/j.jhazmat.2021.125900DOI Listing
April 2021

NIH Funding of Researchers in Surgery: Decreased Career Development Awards Over Time.

J Surg Res 2021 May 8;266:6-12. Epub 2021 May 8.

Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama.

Background: Over time, NIH funding has become increasingly competitive. In addition, academic surgeons' research competes with time required for patient care, operating, and administrative work. Due to these competing interests for surgeons, we hypothesize that the percentage of NIH grants awarded to researchers from departments of surgery is decreasing.

Methods: The NIH Research Portfolio Online Reporting Tool was queried for the number and value of new and renewal R01 grants, and career development awards noting which surgery departments received awards from 1998 to -2018. Statistical analysis was performed using univariate and multivariable logistic regression.

Results: The number of career development awards granted to researchers from departments of surgery decreased significantly over time (P = 0.007) while new R01's and R01 renewal awards were stable. The number of grants awarded to researchers from all procedural departments were compared to non-procedural departments and again, career development awards decreased significantly (P = 0.005) over time but new R01's and R01 renewals stayed stable. Looking at the difference in average dollar amount received for new R01, renewal R01, or career development awards between department of surgery awardees and non-surgery over time, there was no significant difference.

Conclusions: NIH funding is becoming increasingly competitive and surgeons have many competing interests. Our study found that there has been a significant decrease in career development awards to department of surgery awardees and procedural specialists. The decrease in receipt of these awards is particularly concerning given that they are meant to provide protected time for developing researchers and thus have potential consequences for future research.
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http://dx.doi.org/10.1016/j.jss.2021.02.053DOI Listing
May 2021

Plastrum testudinis extract suppresses osteoclast differentiation via the NF-κB signaling pathway and ameliorates senile osteoporosis.

J Ethnopharmacol 2021 May 8:114195. Epub 2021 May 8.

The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China; Lingnan Medical Research Center of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China. Electronic address:

Ethnopharmacological Relevance: Plastrum testudinis (PT) is a kind of single traditional Chinese medicine that can tonify kidney and strengthen bone. Plastrum testudinis extract (PTE) has been approved to promote the osteogenic differentiation of bone marrow-derived mesenchymal stem cells in vitro. However, the mechanism by which PTE reduces osteoclast differentiation has not yet been reported.

Aim Of The Study: To explore the potential of PTE as a therapeutic treatment for bone loss caused by senile osteoporosis (SOP).

Materials And Methods: We evaluated whether PTE could inhibit RANKL-induced osteoclast differentiation both in vitro and in vivo, and investigated PTE-induced phenotypes of human peripheral blood monocytes.

Results: We found that PTE inhibited osteoclast differentiation and bone resorption in vitro in a concentration-dependent manner and that PTE treatment is most effective during the early stages of osteoclastogenesis. Moreover, we found that PTE could block the NF-κB signaling pathway in vitro, leading to the down-regulation of osteoclast-specific genes including C-FOS and NFATC1. The results from our in vivo mouse study suggest that PTE treatment suppresses osteoclast formation and mitigates bone loss caused by SOP. Notably, we also found that PTE inhibited RANKL-induced osteoclast differentiation in human peripheral blood monocytes.

Conclusion: Our results suggest that PTE treatment suppresses osteoclastogenesis and ameliorates bone loss caused by SOP by selectively blocking the nuclear translocation of NF-κB/p50.
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http://dx.doi.org/10.1016/j.jep.2021.114195DOI Listing
May 2021

Incorporating Guanidinium as Perovskitizer-Cation of Two-Dimensional Metal Halide for Crystal-Array Photodetector.

Chem Asian J 2021 May 11. Epub 2021 May 11.

Chinese Academy of Sciences Fujian Institute of Research on the Structure of Matter, State Key Laboratory of Structural Chemistry, Yangqiao West Road 155, GuLou District, 350002, Fuzhou, CHINA.

Two-dimensional (2D) hybrid perovskites are recently emerging as a potential family of semiconductors for versatile optoelectronic applications. Currently, the "perovskitizer" moieties are rigidly limited to the small-size cations, while few 2D metal-halides composing of guanidinium cation inside perovskite cages have been studied for photodetection. Herein, we present a new 2D hybrid perovskite, (i -BA)2GPb 2 I 7 (where G is guanidinium and i -BA is isobutylammonium), which adopts the bilayered frameworks of {GPb 2 I 7 }. Single-crystal structure analyses disclose that G cations act as the perovskitizer, confined in the flexible perovskite cages formed by the distorted PbI 6 octahedra. Such inorganic sheets are crucial to the superior semiconducting properties and optical bandgap, as verified by the density functional theory calculation. Furthermore, its planar crystal-array photodetector shows fascinating photoelectric performances, including quite low dark current (~4.6×10 -11 A), large current switching ratio (~1.0×10 3 ), and notable photo-responsivity of ~0.72 A W -1 , suggesting great potentials of ( i -BA) 2 (G)Pb 2 I 7 for photodetection.
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http://dx.doi.org/10.1002/asia.202100425DOI Listing
May 2021