Exploring the Cocktail Factor Approach to Generate Salivary Gland Progenitors through Co-Culture Techniques

Zhang Yifei,Yan Shuang,Mei Zi,Zhang He,Ding Chong,Zhang Siqi,Wei Shicheng 한국조직공학과 재생의학회 2024 조직공학과 재생의학 Vol.21 No.5

Background: The derivation of salivary gland (SG) progenitors from pluripotent stem cells (PSCs) presents significant potential for developmental biology and regenerative medicine. However, the existing protocols for inducing SG include limited factors, making it challenging to mimic the in vivo microenvironment of embryonic SGs. Methods: We reported a cocktail factor approach to promote the differentiation of mouse embryonic stem cell (mESC)-derived oral epithelium (OE) into SG progenitors through a three-dimensional co-culture method. Upon confirming that the embryonic SG can promote the differentiation of mESC-derived OE, we performed RNA sequence analysis to identify factors involved in the differentiation of SG progenitors. Results: Our findings highlight several efficient pathways related to SG development, with frequent appearances of four factors: IFN-γ, TGF-β2, EGF, and IGF-1. The combined treatment using these cocktail factors increased the expression of key SG progenitor markers, including Sox9, Sox10, Krt5, and Krt14. However, absence of any one of these cocktail factors did not facilitate differentiation. Notably, aggregates treated with the cocktail factor formed SG epithelial-like structures and pre-bud-like structures on the surface. Conclusion: In conclusion, this study offers a novel approach to developing a differentiation protocol that closely mimics the in vivo microenvironment of embryonic SGs. This provides a foundation for generating PSC-derived organoids with near-physiological cell behaviors and structures. Background: The derivation of salivary gland (SG) progenitors from pluripotent stem cells (PSCs) presents significant potential for developmental biology and regenerative medicine. However, the existing protocols for inducing SG include limited factors, making it challenging to mimic the in vivo microenvironment of embryonic SGs. Methods: We reported a cocktail factor approach to promote the differentiation of mouse embryonic stem cell (mESC)-derived oral epithelium (OE) into SG progenitors through a three-dimensional co-culture method. Upon confirming that the embryonic SG can promote the differentiation of mESC-derived OE, we performed RNA sequence analysis to identify factors involved in the differentiation of SG progenitors. Results: Our findings highlight several efficient pathways related to SG development, with frequent appearances of four factors: IFN-γ, TGF-β2, EGF, and IGF-1. The combined treatment using these cocktail factors increased the expression of key SG progenitor markers, including Sox9, Sox10, Krt5, and Krt14. However, absence of any one of these cocktail factors did not facilitate differentiation. Notably, aggregates treated with the cocktail factor formed SG epithelial-like structures and pre-bud-like structures on the surface. Conclusion: In conclusion, this study offers a novel approach to developing a differentiation protocol that closely mimics the in vivo microenvironment of embryonic SGs. This provides a foundation for generating PSC-derived organoids with near-physiological cell behaviors and structures.

Resource Recovery from Biomass Waste by Hydrothermal Conversion Process - Towards Circular Bioeconomy

( Shicheng Zhang ) 한국폐기물자원순환학회(구 한국폐기물학회) 2021 한국폐기물자원순환학회 심포지움 Vol.2021 No.1

A MAXIMUM PRINCIPLE FOR COMPLETE HYPERSURFACES IN LOCALLY SYMMETRIC RIEMANNIAN MANIFOLD

Zhang, Shicheng Korean Mathematical Society 2014 대한수학회논문집 Vol.29 No.1

In this article, we apply the weak maximum principle in order to obtain a suitable characterization of the complete linearWeingarten hypersurfaces immersed in locally symmetric Riemannian manifold $N^{n+1}$. Under the assumption that the mean curvature attains its maximum and supposing an appropriated restriction on the norm of the traceless part of the second fundamental form, we prove that such a hypersurface must be either totally umbilical or hypersurface is an isoparametric hypersurface with two distinct principal curvatures one of which is simple.

Hydrothermal conversion of biomass waste to high value-added chemicals and materials

Shicheng ZHANG,Gang LUO,Xiangdong ZHU 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

ON THE STABILITY OF SPACELIKE HYPERSURFACES WITH HIGHER ORDER MEAN CURVATURE IN A DE SITTER SPACE

Zhang, Shicheng Korean Mathematical Society 2014 대한수학회보 Vol.51 No.5

The closed spacelike hypersurfaces with higher order mean curvature is discussed in a de Sitter space. The hypersurface is proved stable if and only if it is totally umbilical.

On the stability of spacelike hypersurfaces with higher order mean curvature in a de Sitter space

Shicheng Zhang 대한수학회 2014 대한수학회보 Vol.51 No.5

The closed spacelike hypersurfaces with higher order mean curvature is discussed in a de Sitter space. The hypersurface is proved stable if and only if it is totally umbilical.

Determining Osteogenic Differentiation Efficacy of Pluripotent Stem Cells by Telomerase Activity

Siqi Zhang,Yuhua Sun,Yi Sui,Yan Li,Zuyuan Luo,Xiao Xu,Ping Zhou,Shicheng Wei 한국조직공학과 재생의학회 2018 조직공학과 재생의학 Vol.15 No.6

BACKGROUND: Bone tissue engineering based on pluripotent stem cells (PSCs) is a new approach to deal with bone defects. Protocols have been developed to generate osteoblasts from PSCs. However, the low efficiency of this process is still an important issue that needs to be resolved. Many studies have aimed to improve efficiency, but developing accurate methods to determine efficacy is also critical. Studies using pluripotency to estimate efficacy are rare. Telomerase is highly associated with pluripotency. METHODS: We have described a quantitative method to measure telomerase activity, telomeric repeat elongation assay based on quartz crystal microbalance (QCM). To investigate whether this method could be used to determine the efficiency of in vitro osteogenic differentiation based on pluripotency, we measured the pluripotency pattern of cultures through stemness gene expression, proliferation ability and telomerase activity, measured by QCM. RESULTS: We showed that the pluripotency pattern determined by QCM was similar to the patterns of proliferation ability and gene expression, which showed a slight upregulation at the late stages, within the context of the general downregulation tendency during differentiation. Additionally, a comprehensive gene expression pattern covering nearly every stage of differentiation was identified. CONCLUSION: Therefore, this assay may be powerful tools for determining the efficiency of differentiation systems based on pluripotency. In this study, we not only introduce a new method for determining efficiency based on pluripotency, but also provide more information about the characteristics of osteogenic differentiation which help facilitate future development of more efficient protocols.

MRI Findings in Trigeminal Neuralgia without Neurovascular Compression: Implications of Petrous Ridge and Trigeminal Nerve Angles

Zhong Hai,Zhang Wenshuang,Sun Shicheng,Bie Yifan 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.8

Objective: To determine the anatomical characteristics of the petrous ridge and trigeminal nerve in trigeminal neuralgia (TN) without neurovascular compression (NVC). Materials and Methods: From May 2017 to March 2021, 66 patients (49 female and 17 male; mean age ± standard deviation [SD], 56.8 ± 13.3 years) with TN without NVC and 57 controls (46 female and 11 male; 52.0 ± 15.6 years) were enrolled. The angle of the petrous ridge (APR) and angle of the trigeminal nerve (ATN) were measured using magnetic resonance imaging with a high-resolution three-dimensional T2 sequence. Data on the symptomatic side were compared with those on the asymptomatic side in patients and with the mean measurements of the bilateral sides in controls. Receiver operating characteristic (ROC) analysis was conducted to evaluate the performance of APR and ATN in distinguishing TN patients from controls. Results: In TN patients without NVC, the mean ± standard deviation (SD) of APR on the symptomatic side (98.40° ± 19.75°) was significantly smaller than that of the asymptomatic side (105.59° ± 22.45°, p = 0.019) and controls (108.44° ± 15.98°, p = 0.003). The mean ATN ± SD on the symptomatic side (144.41° ± 8.92°) was significantly smaller than that of the asymptomatic side (149.67° ± 8.09°, p = 0.003) and controls (150.45° ± 8.48°, p = 0.001). The area under the ROC curve for distinguishing TN patients from controls was 0.673 (95% confidence interval [CI]: 0.579–0.758) for APR and 0.700 (CI: 0.607–0.782) for ATN. The sensitivity and specificity using the diagnostic cutoff yielding the highest Youden index were 81.8% (54/66) and 49.1% (28/57), respectively, for APR (with a cutoff score of 94.30°) and 65.2% (43/66) and 66.7% (38/57), respectively, for ATN (cutoff score, 148.25°). Conclusion: In patients with TN without NVC, APR and ATN were smaller than those in controls, which may explain the potential cause of TN and provide additional information for diagnosis.

Robust Consensus for Networked Mechanical Systems with Coupling Time Delay

Haibo Min,Shicheng Wang,Fuchun Sun,Jinsheng Zhang 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.2

This paper studies the state consensus for a class of networked nonlinear mechanical systems with coupling time delay. In particular, robust consensus protocols for both deterministic and uncertain systems with time delay are investigated. For deterministic systems, we develop a P-like protocol which allows for variable coupling time delay. We show that it is sufficient to have only the relative position information together with a damping control term, whereas the relative velocity information is not needed for state consensus. Then, an adaptive robust control protocol is proposed for uncertain sys-tems with unknown parameters in the system dynamics and arbitrary constant coupling time delays. By introducing the passivity-based framework, we demonstrate that state consensus is still reachable in this case. Finally, a numerical example is included to illustrate the obtained results.

A hybrid decoding of Reed–Muller codes

Li, Shuang,Zhang, Shicheng,Chen, Zhenxing,Kang, Seog Geun Taylor & Francis 2017 INTERNATIONAL JOURNAL OF DISTRIBUTED SENSOR NETWOR Vol.13 No.2