Basic fibroblast growth factor promotes human dental pulp stem cells cultured in 3D porous chitosan scaffolds to neural differentiation.

AIM/PURPOSE: Dental pulp stem cells (DPSCs) were widely used as seed cells in the field of tissue engineering and regenerative medicine, including spinal cord injury (SCI) repair and other neuronal degenerative diseases, due to their easy isolation, multiple differentiation potential, low immunogenicity and low rates of rejection during transplantation. Various studies have shown that bFGF can enhance peripheral nerve regeneration after injury, and phospho-ERK (p-ERK) activation as a major mediator may be involved in this process. Previous studies also have proved that a suitable biomaterial scaffold can carry and transport the therapeutic cells effectively to the recipient area. It has showed in our earlier experiments that 3D porous chitosan scaffolds exhibited a suitable circumstance for survival and neural differentiation of DPSCs in vitro. The purpose of the study was to evaluate the influence of chitosan scaffolds and bFGF on differentiation of DPSCs. MATERIALS AND METHODS: In current study, DPSCs were cultured in chitosan scaffolds and treated with neural differentiation medium for 7 days. The neural genes and protein markers were analyzed by western blot and immunofluorescence. Meanwhile, the relevant signaling pathway involved in this process was also tested. RESULTS: Our study revealed that the viability of DPSCs was not influenced by co-culture with the chitosan scaffolds as well as bFGF. Compared with the control and DPSC/chitosan-scaffold groups, the levels of GFAP, S100ß and ß-tubulin III significantly increased in the DPSC/chitosan-scaffold+bFGF group. CONCLUSION: Chitosan scaffolds were non-cytotoxic to the survival of DPSCs, and chitosan scaffolds combined with bFGF facilitated the neural differentiation of DPSCs. The transplantation of DPSCs/chitosan-scaffold+bFGF might be a secure and effective method of treating SCI and other neuronal diseases.

Non-suicidal self-injury function: prevalence in adolescents with depression and its associations with non-suicidal self-injury severity, duration and suicide.

Background: Given that adolescents with depression are at the highest risk for non-suicidal self-injury (NSSI), a thorough understanding of their NSSI functions, as well as associations between functions and severe behavioral consequences, is essential for risk assessment and invention development. Methods: Adolescents with depression from 16 hospitals across China, for whom data was available regarding their NSSI function, frequency, number of methods used, time characteristics, and suicide history were included. Descriptive statistical analyses were performed to determine the prevalence of NSSI functions. Regression analyses were conducted to explore the relationship between NSSI functions and behavioral characteristics of NSSI and suicide attempts. Results: Affect regulation was the primary function of NSSI and followed by anti-dissociation in adolescents with depression. Females recognized automatic reinforcement functions more frequently than males, while males had a higher prevalence of social positive reinforcement functions. Automatic reinforce functions played the prominent role in associations between NSSI functions and all the severe behavioral consequences. Specifically, functions of anti-dissociation, affect regulation, and self-punishment were all associated with NSSI frequency, while higher levels of endorsements for anti-dissociation and self-punishment were linked to more NSSI methods, and greater level of endorsement for anti-dissociation was related to longer NSSI duration. Only the increase in endorsement of self-punishment was associated with a greater hazard of suicide attempts. Conclusion: The dominant functions of NSSI in adolescents with depression was automatic reinforcement, specifically affect regulation. And prevalence of NSSI function differed between males and females. Anti-dissociation and self-punishment seemed to be the most risky factors as they were linked to severe NSSI or suicide behaviors. More attention should be given to these functions in risk evaluation, and the targeted interventions should be developed accordingly in a timely manner.

Construction of Reinforced Self-Cleaning and Efficient Photothermal PDMS@GDY@Cu Sponges toward Anticorrosion and Antibacterial Applications.

Copper (Cu)-based materials are widely used in many fields from industry to life, including marine, medical apparatus and instruments, and microelectronic devices owing to their superior thermal, electrical, and mechanical properties. However, the interaction of copper with aggressive and fouling liquids under normal circumstances easily brings about severe bacterial accumulation, resulting in undesirable functionality degeneration and bacterial infections. In this contribution, we reported a novel copper-based sponge, polydimethylsiloxane (PDMS)@graphdiyne (GDY)@Cu, constructed by in situ synthesis of GDY on a commercial Cu sponge, followed by the modification of PDMS. The as-fabricated PDMS@GDY@Cu sponge not only possesses excellent self-cleaning activity against the pollution of daily drinks and dirt due to an improved static contact angle (~136°), but also display a remarkably enhanced anticorrosion performance, attributed to intimate coverage of chemically stable GDY and PDMS on the Cu sponge. Based on high photothermal effect of GDY, the PDMS@GDY@Cu sponge also displays significantly improved antibacterial activities under irradiation. In addition, due to excellent chemical stability of PDMS and GDY, self-cleaning behavior and photothermal-assisted antibacterial performance are well maintained after long-term attack of bacteria. These results demonstrate that GDY-based functional coatings hold great promises in the protection of copper devices under harsh conditions.

2D MXene Ti3C2T x nanosheets in the development of a mechanically enhanced and efficient antibacterial dental resin composite.

The bacterial accumulation at the margins of dental resin composites is a main cause of secondary caries, which may further lead to prosthodontic failure. In this regard, this study for the first time incorporated 2D MXene Ti3C2Tx nanosheets (NSs) into epoxy resin at different mass ratios (0, 0.5, 1.0, and 2.0 wt%) by solution blending and direct curing for dental applications. Compared to the pure resin, the as-fabricated MXene/resin composite not only exhibited improved mechanical and abrasive results but also displayed gradually improved antibacterial activity with MXene loading which was further enhanced by illumination in natural light due to the high photothermal efficiency of MXene. In addition, the cytotoxicity result demonstrated that the MXene-modified resin did not cause severe damage to normal cells. This novel MXene/resin nanocomposite could pave the way for new designs for high-performance, multifunctional nanocomposites to effectively protect dental health in daily life.

Bismuth Quantum Dot (Bi QD)/Polydimethylsiloxane (PDMS) Nanocomposites with Self-Cleaning and Antibacterial Activity for Dental Applications.

In the oral microenvironment, bacteria colonies are easily aggregated on the tooth-restoration surface, in the manner of a biofilm, which usually consists of heterogeneous structures containing clusters of a variety of bacteria embedded in an extracellular matrix, leading to serious recurrent caries. In this contribution, zero-dimensional (0D) bismuth (Bi) quantum dots (QDs) synthesized by a facile solvothermal method were directly employed to fabricate a Bi QD/polydimethylsiloxane (PDMS)-modified tooth by simple curing treatment. The result demonstrates that the as-fabricated Bi QD/PDMS-modified tooth at 37 °C for 120 min not only showed significantly improved hydrophobic performance with a water contact angle of 103° and 115° on the tooth root and tooth crown, respectively, compared to that (~20° on the tooth root, and ~5° on the tooth crown) of the pristine tooth, but also exhibited excellent antibacterial activity against S. mutans, superior biocompatibility, and biosafety. In addition, due to the highly photothermal effect of Bi QDs, the antibacterial activity of the as-fabricated Bi QD/PDMS-modified tooth could be further enhanced under illumination, even at a very low power density (12 mW cm-2). Due to the facile fabrication, excellent hydrophobicity, superior antibacterial activity, and biocompatibility and biosafety of the Bi QD/PDMS-modified tooth, it is envisioned that the Bi QD/PDMS-modified tooth with a fascinating self-cleaning and antibacterial performance can pave the way to new designs of versatile multifunctional nanocomposites to prevent secondary caries in the application of dental restoration.

RASSF10 exhibits tumor­suppressing potential involving tumor proliferation, metastasis and epithelial­mesenchymal transition in esophageal squamous cell carcinoma.

Growing evidence indicates that Ras­association domain family 10 (RASSF10) is a novel tumor­suppressor gene that is involved in the inhibition of tumor progression and metastasis; however, the biological functions and molecular mechanisms of RASSF10 in esophageal squamous cell carcinoma (ESCC) have not yet been thoroughly elucidated. The expression of RASSF10 in ESCC tissues and adjacent non­tumor tissues was investigated employing quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC) assays of tissue microarrays. The function of RASSF10 in ESCC cell growth, migration and invasion was determined by CCK­8, colony formation, scratch wound healing and Transwell invasion assays, respectively. The correlation between RASSF10 and markers related to epithelial­mesenchymal transition (EMT) was evaluated by tissue microarray (TMA)­IHC, western blotting and immunofluorescence staining. RASSF10 was found to be highly downregulated in ESCC tissues compared with that noted in the adjacent non­tumor tissues, and closely correlated with tumor progression and patient prognosis. Moreover, functional studies demonstrated that RASSF10 overexpression not only resulted in reduced cell growth and colony formation but also inhibited migration and invasion of the ESCC cells. Tumor RASSF10 expression was positively correlated with E­cadherin expression and negatively correlated with vimentin. In addition, it was demonstrated that the antineoplastic functions of RASSF10 mediate inactivation of the Wnt/ß­catenin pathway in ESCC. Our findings revealed that RASSF10 may constitute a prognostic factor for ESCC patients and a crucial candidate for targeted therapy against ESCC.

Role of mTOR complex in IGF-1 induced neural differentiation of DPSCs.

Recent studies have demonstrated that IGF-1 modulates the pluripotent differentiation of dental pulp stem cells (DPSCs). Although mTOR pathway activation has been showed as responsible for IGF-1 induced pluripotent differentiation, the mechanism that the IGF-1-mTOR pathway induces the neural differentiation of DPSCs is still unclear. In our research, we have demonstrated that 0-10 ng/mL IGF-1 had no obvious effect on the proliferation of DPSCs, but IGF-1 nonetheless enhances the neural differentiation of DPSCs in a dose-dependent manner. Simultaneously, we found that phosphorylated mTOR was up-regulated, which indicated the involvement of mTOR in the process. Rapamycin, an inhibitor of mTOR activity, can reverse the effect of DPSCs stimulated by IGF-1. Next, we studied the role of mTORC1 and mTORC2, two known mTOR complexes, in the neural differentiation of DPSCs. We found that inhibition of mTORC1 can severely restricts the neural differentiation of DPSCs. However, inhibition of mTORC2 has the opposite effect. This latter effect disappears when both rictor and mTOR are inhibited, showing that the mTORC2 effect is mTORC1 dependent. This study has expanded the role of mTOR in DPSCs neural differentiation regulated by IGF-1.

Primary atypical teratoid/rhabdoid tumor of central nervous system in children: a clinicopathological analysis and review of literature in China.

Atypical teratoid/rhabdoid tumor (AT/RT) is a very rare and highly malignant embryonal tumor in the central nervous system (CNS). Five patients (4 girls and 1 boy) with AT/RT were treated in our hospital. The clinical histories, symptoms, neuroimaging aspects, therapies, histological and immunohistochemical findings and follow-up information were reviewed. The patients ranged from 8 to 40 months with a mean age of 20.6 months. One tumor was located in the spinal cord, two in cerebellum and two in the pineal region. The imagings of the tumors resemble medulloblastomas. Pathological examinations showed that one patient had medulloblastoma differentiation, one had choroid plexus carcinoma differentiation, and one had mesenchymal components. Immunohistochemical staining showed that all of the tumors lost the nuclear expression of integrase interactor 1 (INI1), and were positive for Vimentin, S-100 protein and epithelial membrane antigen. One case with no recurrence after 24 months may have benefited from radical excision and postoperative radiotherapy. The other 4 patients died 8, 4, 1 and 1-month respectively after operation without radiotherapy. The diagnosis of AT/RT depends on full sampling, careful observation the morphological characteristics and INI1 examination, even when the tumor are presented in uncommon sites, such as the spinal cord and the pineal region.

Genetic polymorphisms and serum levels of mannose-binding lectin in Chinese pediatric patients with common infectious diseases.

BACKGROUND: Mannose-binding lectin (MBL) is a collagen-like serum protein that plays an important role in first-line host defense, especially in infants and young children. The objective of this study was to explore the genetic polymorphisms and serum protein levels of MBL in Chinese pediatric patients with common infectious diseases, including recurrent respiratory infection (RRI), acute respiratory infection (ARI), active cytomegalovirus (CMV) infection, localized abscess, and otitis media. METHODS: MBL genetic polymorphisms of 151 pediatric patients with infectious diseases and 105 healthy controls were detected by PCR and sequencing. Serum MBL levels of all the patients and controls were measured using a Human MBL ELISA Kit. Differences in MBL genetic polymorphisms and serum levels between patients and controls were analyzed by statistical methods. RESULTS: The frequencies of allele H/L at position -550 of the promoter and three haplotypes - HYPA, HYPB, and LYPB - were statistically different between patients and controls (p<0.05). The frequencies of genotypes 'YA' and 'XB', relevant to serum protein levels, were also significantly different between patients and controls (p<0.05). Serum MBL levels of patients with active CMV infection were significantly lower than those of controls (p<0.05). Conversely, serum MBL levels of patients with ARI and localized abscess were significantly higher than those of controls (p<0.05). CONCLUSIONS: Genetic polymorphisms attributable to mutations in the promoter and exon 1 of the MBL2 gene appear to be relatively common in pediatric patients with infectious diseases. Low serum MBL levels may play a role in the high sensitivity of pediatric CMV infections.

Association between mannose-binding lectin gene polymorphism and pediatric cytomegalovirus infection.

Mannose-binding lectin (MBL) is an important constituent of the human innate immune system, and can bind to a wide range of pathogens, including viruses such as influenza A, HIV, herpes simplex 2, and SARS-CoV. MBL deficiency results from single nucleotide polymorphisms (SNPs) in exon 1, and the promoter region of the human MBL2 gene has been found to be associated with susceptibility to a number of infections. However, studies on the interactions between MBL and CMV infection are limited. In this study, we investigated 104 children suffering from HCMV infection, in an effort to find any association between MBL and HCMV infection of children in China. We analyzed the genotypes of 104 HCMV patients and 105 healthy controls, and investigated the distributions of polymorphisms at -550(H/L), -221(Y/X), and +4(P/Q), together with their structural variants. Although there was no significant difference in the distribution of B alleles between HCMV patients and healthy controls, the frequencies of the high-MBL-level related genotype of YA type in HCMV patients were significantly lower than those seen in healthy controls, while low-level related genotypes of XB type were more common in HCMV patients. In addition, CMV-DNA quantification revealed higher viral loads of the XB type in HCMV patients. Thus we can speculate that as an acute response protein and a pattern-recognition molecule of the innate immune system, MBL may play a role in protecting against HCMV infection in children, and MBL gene mutations may be a significant risk factor for the development of infantile HCMV infection.