Both parents migrating and left-behind children's cognitive ability in rural China: does it pay?

Introduction: While the well-documented negative correlation between both parents migrating and the academic performance of left-behind children (LBC) in rural China is widely acknowledged, it's important to recognize that statistical data reveals millions of children experiencing both parents migrating. This discrepancy between the documented negative impact and the prevalence of both parents migrating can be attributed to previous studies primarily focusing on the direct effects. Methods: Employing national representative panel data and FE model, this study estimates the direct impact of both parents migrating and the indirect effects of both parents migrating through private tutoring, family tutoring, family income, and boarding school participation. Finally, we consolidate the direct and indirect impacts to determine whether both parents migrating has a positive or negative net effect on LBC's cognitive ability. Results: The direct effect of both parents migrating on LBC's standardized cognitive ability is -0.140, indicating a negative direct impact of both parents migrating on LBC's cognitive ability. However, the indirect effects of both parents migrating through private tutoring, family tutoring, family income, and boarding school participation are -0.017, -0.008, 0.306 and 0.119 respectively. The toal effect of both parents migrating on LBC's standardized cognitive ability is 0.260. Conclusion: The initially observed negative direct impact of both parents' migrating can be completely offset by the indirect impact channels, including private tutoring, family tutoring, family income, and boarding school participation. In contrast to prior research, this study unveils a positive overall impact of both parents' migration on LBC's school performance.

Prognostic value of pre-treatment PNH clone among the patients with aplastic anemia: a meta-analysis.

BACKGROUND: Paroxysmal nocturnal hemoglobinuria (PNH) clone can be detected in some patients with aplastic anemia (AA) before treatment. But the prognostic value of the presence of pre-treatment PNH clone for intensive immunosuppressive therapy (IIST) is controversial and no consensus on whether the occurrence of PNH/AA-PNH syndrome is related to pre-treatment PNH clone. OBJECTIVE: This study aims to summarize the prognostic value of the presence of pre-treatment PNH clone treated with IIST among the AA patients and to elucidate its relationship with the development of PNH / AA-PNH syndrome. METHODS: All published studies on the prognostic value of pre-treatment PNH clone among AA patients were retrieved. Pooled odds ratio (OR) was calculated to compare the rates, along with 95% confidence intervals (CI) and p value to assess whether the results were statistically significant. RESULTS: The meta-analysis consisted of 15 studies with a combined total of 1349 patients in the cohort. Pre-treatment PNH clone had a positive effect on AA patients 6-month (pooled OR = 1.49,95% Cl: 1.06-2.08, P = 0.020), 12-month (pooled OR = 3.10,95% Cl: 1.89-5.10, P = 0.000), and overall hematological response rate (pooled OR = 1.69,95% Cl: 1.07-2.68, P = 0.024) after IIST. Patients with pre-treatment PNH clone are more likely to develop PNH/AA-PNH syndrome after IIST(pooled OR = 2.78,95%Cl:1.21-6.39, P = 0.016). CONCLUSION: Patients with positive pre-treatment PNH clone had better hematological responses to IIST than negative. And, those patients are more likely to develop PNH/AA-PNH syndrome after IIST.

Fabrication and characterization of drug-loaded nano-hydroxyapatite/polyamide 66 scaffolds modified with carbon nanotubes and silk fibroin.

Nano-hydroxyapatite/polyamide 66 (nHA/PA66) porous scaffolds were fabricated by a phase inversion method. Carbon nanotubes (CNTs) and silk fibroin (SF) were used to modify the surface of the nHA/PA66 scaffolds by freeze-drying and cross-linking. Dexamethasone was absorbed to the CNTs to promote the osteogenic differentiation of bone mesenchymal stem cells (BMSCs). The cell viability of BMSCs was investigated by changing the concentration of the CNT dispersion, and the most biocompatible scaffold was selected. In addition, the morphology and mechanical property of the scaffolds were investigated. The results showed that the nHA/PA66 scaffolds modified with CNTs and SF met the requirements of bone tissue engineering scaffolds. The dexamethasone-loaded CNT/SF-nHA/PA66 composite scaffold promoted the osteogenic differentiation of BMSCs, and the drug-loaded scaffolds are expected to function as effective bone tissue engineering scaffolds.

[Research progress on application of carbon nanotubes in bone tissue engineering scaffold].

Carbon nanotubes possess excellent mechanical and electrical properties and demonstrate broad application prospects in medical fields. Carbon nanotubes are composed of inorganic materials, natural biodegradable polymer or synthetic biodegradable polymer. The composite bone tissue engineering scaffolds are constructed by particle-hole method, lyophilization, microsphere aggregation method, electrostatic spinning or three-dimensional printing. Composite scaffolds overcome the shortcomings of single material and have good biocompatibility, osteoconduction and osteoinduction. With the study of surface chemistry, toxicology, and biocompatibility, a degradable "human-friendly" carbon nanotubes composite bone tissue scaffold will be available; and under the drive of new fabrication techniques, the clinical application of carbon nanotubes composite bone tissue engineering scaffolds will be better developed.

Toxicity analysis of various Pluronic F-68-coated carbon nanotubes on mesenchymal stem cells.

Carbon nanotubes (CNTs) have poor colloid stability in biological media and exert cytotoxic effects on mesenchymal stem cells (MSCs). Modification with polymeric surfactant is a widely used strategy to enhance water dispersibility of CNTs. This study investigated the toxic effects of various Pluronic F-68 (PF68)-coated multi-walled CNTs (MWCNTs) on rat bone marrow-derived MSCs.PF68-coated MWCNTs showed favorable biocompatibility to MSCs that the cell viability, apoptosis, and reactive oxygen species (ROS) were not altered after 24 h of co-incubation. Nevertheless, significant apoptosis induction and massive ROS release were found following extended exposure (48 and 72 h), and the toxic impact was dependent on the initial surface properties of the encapsulated MWCNTs. All the types of PF68-coated MWCNTs did not affect the cell-surface markers and in vivo biodistribution of MSCs. Our results suggest that proper polymer coating can reduce the acute toxicity of MWCNTs to MSCs but without altering their biological fate.