Stimulating factors for regulation of osteogenic and chondrogenic differentiation of mesenchymal stem cells

Mesenchymal stem cells(MSCs),distributed in many tissues in the human body,are multipotent cells capable of differentiating in specific directions.It is usually considered that the differentiation process of MSCs depends on specialized external stimulating factors,including cell signaling pathways,cytokines,and other physical stimuli.Recent findings have revealed other underrated roles in the differentiation process of MSCs,such as material morphology and exosomes.Although relevant achievements have substantially advanced the applicability of MSCs,some of these regulatory mechanisms still need to be better understood.Moreover,limitations such as long-term survival in vivo hinder the clinical application of MSCs therapy.This review article summarizes current knowledge regarding the differentiation patterns of MSCs under specific stimulating factors.

Comparative studies on Fenton-like reactions catalyzed by Fe_(3)O_(4) loaded inside and outside halloysite nanotubes for the removal of organic pollutants

In this work,Fe_(3)O_(4) nanoparticles(NPs)loaded inside and outside halloysite nanotubes(HNTs)were prepared and developed as the heterogeneous Fenton-like catalysts for the removal of representative organic pollutants.Characterization results indicated that the samples with Fe_(3)O_(4) NPs loaded outside the HNTs lumen(Fe_(3)O_(4)/HNTs)and inside the HNTs lumen(Fe_(3)O_(4)@HNTs)were successfully prepared.Both samples had typical magnetic hysteresis loops,while Fe_(3)O_(4)@HNTs exhibited higher magnetization intensity.The comparative experiments showed that Fe_(3)O_(4)@HNTs had better Fenton-like catalytic ability than that of Fe_(3)O_(4)/HNTs in the degradation of various organic pollutants.Taking Rhodamine B(RhB)as an example,the adsorption thermodynamics and kinetics of RhB onto Fe_(3)O_(4)/HNTs and Fe_(3)O_(4)@HNTs were also investigated.The comparative results demonstrated that the adsorption ability of Fe_(3)O_(4)/HNTs was better than that of Fe_(3)O_(4)@HNTs.Moreover,the dissolved concentration of Fe^(2+)and production amount of hydroxyl radical(·OH)in the Fe_(3)O_(4)@HNTs-H_(2)O_(2) system were significantly higher than those in the Fe_(3)O_(4)/HNTs-H_(2)O_(2) system.Based on aforementioned comparison,the nano-confinement effect in the Fe_(3)O_(4)@HNTs-H_(2)O_(2) system was verified.This work provides meaningful guidance for the cheap and convenient design of nanoreactors for Fenton-like applications.

The programmed death of fetal oocytes and the correlated surveillance mechanisms

Gamete production is essential for mammalian reproduction.In the ovaries,the primordial follicle,which is the basic reproductive unit,is formed either perinatally or during the second pregnancy stage in humans.However,some oocytes die before the establishment of the primordial follicle pool.Consequently,it is essential to uncover how the size of the primordial follicle pool is determined and how the programmed cell death of oocytes is performed under potential surveillance.According to recent studies,the fate of oocytes in the fetal ovary seems to be determined by different protective strategies through the timely control of apoptosis or autophagy.In this review,we discuss at least three oocyte-derived protective biomarkers,glycogen synthase kinase 3 beta,X-linked inhibitor of apoptosis,and Lysine-specific demethylase 1(also known as KDM1A),responsible for surveilling the developmental quality of fetal oocytes to coordinate primordial follicle formation in the fetal ovary.This review contributes to a better understanding of the secrets of the female reproductive reserve under physiological conditions.