Effects of TGF- β

Introduction. This study aimed to explore the effects of TGF-β1 on regulating activities of cementoblasts and osteoblasts with or without stress. Material and Methods. Human recombinant TGF-β1 was added with different doses. Immunohistochemical test of osteoprotegerin (OPG)/receptor activator of nuclear factor-kappaB ligand (RANKL) and Alizarin Red-S staining were conducted. Mechanical compressive stress was obtained by increasing the pressure of gaseous phase. OPG/RANKL expression was detected in both cells through quantitative real-time PCR. Results. Similar significant differences (P<0.05) existed in OPG/RANKL change with increasing concentration of TGF-β1 without mechanical stress for cementoblasts and osteoblasts. However, under 3 h stress, OPG increased and RANKL decreased significantly (P<0.01) but with similar OPG/RANKL change. Moreover, under 24 h stress, OPG change exhibited no difference (P>0.05), but RANKL decreased significantly (P<0.01) at 10 and 100 ng/mL TGF-β1 in cementoblasts. In osteoblasts, OPG increased significantly (P<0.01) at 10 and 100 ng/mL, whereas RANKL decreased with statistical difference (P<0.05) at 1 and 10 ng/mL. Conclusions. The effects of TGF-β1 on OPG/RANKL expression of cementoblasts and osteoblasts are similar even without mechanical stress. However, these effects are different under mechanical compressive stress

Synthesis of TiB2/Ti(C,N) cermet by RSPS: formation mechanism, shrinkage behavior, and mechanical properties

TiB2/Ti(C,N) cermet was prepared by reactive spark plasma sintering from the Co-Ti-BN-C-carbide powder compact. The formation mechanism and shrinkage behavior were studied. Results showed that Ti(C,N) was produced by the diffusion of C atoms into a preformed TiN. TiN-forming reaction was exothermic, which would lead to the occurrence of deep macropores and an abnormal expansion phenomenon. With increasing temperature, the macropores became increasingly shallow. Eventually, they disappeared through the viscous flow and dissolution-reaction-precipitation mechanisms. This behavior was primarily responsible for sintering densification. Among various carbide additives, TaC displayed the optimal effect. The hardness and fracture toughness of cermet reached 1917.4 HV and 8.81 MPa m−1/2. The reason was the formation of a black core/gray rim structure by the diffusion of heavy elements in liquid into the Ti(C,N). Results from the present work could offer a deep understanding of reactive spark plasma sintering, and would be beneficial for the development of Ti(C,N)-based cermet

Analysis of the Potential Relationship between Aging and Pulmonary Fibrosis Based on Transcriptome

Idiopathic pulmonary fibrosis (IPF) is an age-related interstitial lung disease with a high incidence in the elderly. Although many reports have shown that senescence can initiate pulmonary fibrosis, the relationship between aging and pulmonary fibrosis has not been explained systematically. In our study, young and old rats were intratracheally instilled with bleomycin (1 mg/kg), and the basic pathological indexes were determined using a commercial kit, hematoxylin, and eosin (H&E) and Masson’s Trichrome staining, immunohistochemistry, immunohistofluorescence, and q-PCR. Then, the lung tissues of rats were sequenced by next-generation sequencing for transcriptome analysis. Bioinformatics was performed to analyze the possible differences in the mechanism of pulmonary fibrosis between aged and young rats. Finally, the related cytokines were determined by q-PCR and ELISA. The results indicate that pulmonary fibrosis in old rats is more serious than that in young rats under the same conditions. Additionally, transcriptomic and bioinformatics analysis with experimental validation indicate that the differences in pulmonary fibrosis between old and young rats are mainly related to the differential expression of cytokines, extracellular matrix (ECM), and other important signaling pathways. In conclusion, aging mainly affects pulmonary fibrosis through the ECM–receptor interaction, immune response, and chemokines

Axial Motion Characterization of a Helical Ionic Polymer Metal Composite Actuator and Its Application in 3-DOF Micro-Parallel Platforms

In this work, a helical ionic polymer metal composite (IPMC) was fabricated by thermal treatment in a mold with helix grooves. The axial actuation behaviors of the helical IPMC actuator were observed, and the electromechanical and electrochemical characteristics were evaluated. The experimental results showed that as the voltage increased and the frequency decreased, the axial displacement, axial force, and electric current of the actuator all increased. Compared with square wave and sinusoidal signals, the actuator exhibited the most satisfactory motion under the direct current (DC) signal. For the electrochemical test, as the scanning rate decreased, the gravimetric specific capacitance increased. Within a suitable voltage range, the actuator was chemically stable. In addition, we coupled the Electrostatics module, Transport of Diluted Species module, and Solid Mechanics module in COMSOL Multiphysics software to model and analyze the helical IPMC actuator. The simulation data obtained were in good agreement with the experimental data. Finally, by using three helical IPMC actuators as driving components, an innovative three-degree-of-freedom (3-DOF) micro-parallel platform was designed, and it could realize a complex coupling movement of pitch, roll, and yaw under the action of an electric field. This platform is expected to be used in micro-assembly, flexible robots, and other fields

Fecal Microbial Structure and Metabolic Profile in Post-Weaning Diarrheic Piglets

(1) Background: Piglet diarrhea is one of the most serious diseases in pigs and has brought great economic losses to the pig industry. Alteration of the gut microbiota is an important factor in the etiology of piglet diarrhea. Therefore, this study aimed to analyze the differences in the gut microbial structures and fecal metabolic profile between post-weaning diarrhea and healthy Chinese Wannan Black pigs. (2) Methods: An integrated approach of 16S rRNA gene sequencing combined with LC/MS-based metabolomics was employed in this study. (3) Results: We found an increase in the relative abundance of the bacterial genus Campylobacter and a decrease in phylum Bacteroidetes and the species Streptococcus gallolyticus subsp. macedonicus. (S. macedonicus) in piglet diarrhea. Meanwhile, obvious changes in the fecal metabolic profile of diarrheic piglets were also detected, particularly higher levels of polyamines (spermine and spermidine). Moreover, there were substantial associations between the disturbed gut microbiota and the altered fecal metabolites, especially a strong positive relationship between spermidine and Campylobacter. (4) Conclusions: These observations may provide novel insights into potential etiologies related to post-weaning diarrhea and further enhance our understanding of the role of gut microbiota in host homeostasis and in modulating gut microbial structure

Facile Fabrication of PEDOT:PSS‐Based Free‐Standing Conducting Film for Highly Efficient Electromagnetic Interference Shielding

Abstract With the growing popularity of portable and wearable smart electronics, the electromagnetic shielding materials with high shielding effectiveness (SE) as well as light weight and excellent mechanical strength are in high. In this work, the PEDOT:PSS‐based free‐standing conducting film with superior conductivity and mechanical strength is prepared through a facile fabrication. The cellulose nanofibers (CNFs) are first introduced to induce an orderly grow and stack of the PEDOT grains. A phosphoric acid immersion process is then employed to remove the insulating CNF and PSS in the film. The obtained free‐standing conducting film shows a record conductivity of 3508 S cm−1 and its elongation at break reaches 3.75%. Encouragingly, the film delivers an excellent electromagnetic interference (EMI) shielding behavior with a SE of 49 dB in the X‐band (8.2–12.4 GHz) at a thickness of 4 µm. The superior conductivity, mechanical strength, and high SE as well as its facile solution processability make this free‐standing conducting film to be an attractive EMI material for portable and wearable smart electronics