Current multi-scale biomaterials for tissue regeneration following spinal cord injury.

Spinal cord injury (SCI) may cause loss of motor and sensory function, autonomic dysfunction, and thus disrupt the quality of life of patients, leading to severe disability and significant psychological, social, and economic burden. At present, existing therapy for SCI have limited ability to promote neural function recovery, and there is an urgent need to develop innovative regenerative approaches to repair SCI. Biomaterials have become a promising strategy to promote the regeneration and repair of damaged nerve tissue after SCI. Biomaterials can provide support for nerve tissue by filling cavities, and improve local inflammatory responses and reshape extracellular matrix structures through unique biochemical properties to create the optimal microenvironment at the SCI site, thereby promoting neurogenesis and reconnecting damaged spinal cord tissue. Considering the importance of biomaterials in repairing SCI, this article reviews the latest progress of multi-scale biomaterials in SCI treatment and tissue regeneration, and evaluates the relevant technologies for manufacturing biomaterials.

[Research progress on nitrate isotope coupled multi-tracer tracing groundwater nitrate pollution]. / ç¡é ¸ç›åŒä½ç´ è€¦åˆå¤šç¤ºè¸ªå‰‚æº¯æºåœ°ä¸‹æ°´ç¡é ¸ç›æ±¡æŸ“ç ”ç©¶è¿›å±•.

Nitrate pollution in groundwater has become a global concern. One of the most important issues in controlling the nitrate pollution of groundwater is to identify the pollution source quickly and accurately. In this review, we firstly summarized the isotopic background values of potential sources of nitrate pollution in groundwater in 17 provinces (cities, autonomous regions) and 29 study areas in China, which could provide the fundamental database for subsequent research. Secondly, we reviewed the research progress of nitrate isotopes combined with multiple tracers for tracing nitrate in groundwater, and discussed their applicable conditions, advantages, and disadvantages. We found that halides and microorganisms combined with nitrate isotopes could accurately trace the pollution sources of domestic sewage, excrement and agricultural activities. The combination of Δ17O and nitrate isotopes could effectively distinguish the source of atmospheric deposition of nitrate in groundwater. The combination of groundwater age and nitrate isotopes could further determine the time scale of nitrate pollution. In addition, we summarized the application cases and compared the characteristics of mass balance mixing model, IsoSource model, Bayesian isotope mixing model, and EMMTE model for quantitative identification of nitrate pollution in groundwater. For the complexity and concealment of groundwater pollution sources, the coupling of nitrate isotopes with other chemical and biological tracing methods, as well as the application of nitrate isotope quantitative models, are effective tools for reliably identifying groundwater nitrate sources and transformation processes.

A gene co-expression network analysis of the candidate genes and molecular pathways associated with feather follicle traits of chicken skin.

Back and thigh skin of chickens showed significant differences in the thickness and the feather follicle density and size, which are important traits for slaughtered chickens' appearance. In the present study, global gene expression profiling was conducted in the back and thigh skin of chickens using Microarray technology. The results showed that 676 genes were differentially expressed between back and thigh skin. The expression of the differentially expressed genes (DEGs), including PPP1R3C, IGF1, PTCHD1, HOXB6, FGF9, CAMK4, SHH, BMP8B, FOXN1 and PTGER2, was validated by real-time quantitative polymerase chain reaction (RT-qPCR), and the results were consistent with microarray results. Functional analysis revealed that the DEGs were significantly involved in cell proliferation, differentiation, apoptosis, adhesion and transport process, and the pathways were significantly mapped into the ECM-receptor interaction, peroxisome, focal adhesion, Hedgehog and PPAR signalling pathways. Protein-protein interaction network analysis suggested that signalling pathways related to feathers morphogenesis and development, such as Wnt, FGF, MAPK, SHH and BMP signalling pathways, occupied important positions in the network. Genes involved in these signalling pathways and adhesion molecules might play a vital role in skin and feather follicle development. Further single nucleotide polymorphism (SNP) association analysis of Wnt3A showed that the AC genotype of SNP g.255361 C>A significantly increased the feather follicle density of thigh skin. Our findings may provide new insights on candidate genes and pathways related to skin and feather follicle formation of chickens.

Comparison of Intraperitoneal and Intratesticular GYY4137 Therapy for the Treatment of Testicular Ischemia Reperfusion Injury in Rats.

The efficacy of intraperitoneal GYY4137 therapy and intratesticular GYY4137 therapy in an experimental rat model was investigated. Four groups were set up as the sham-operation group, torsion/detorsion (T/D) group, T/D plus intraperitoneal GYY4137 (G-IP) group, and T/D plus intratesticular GYY4137 (G-IT) group. In order to establish a testicular T/D model, the left testis was operated and the rotation reached 720° clockwise which lasted 1 h before reperfusion. The G-IP group accepted 100 µmol/kg of GYY4137 intraperitoneally 30 min after testicular rotation, while the G-IT group was treated with the same dose by intratesticular injection. Six h after detorsion, the testis was collected and subsequently assessed. The T/D group showed significant changes in histology and an enhancement in the level of oxidative stress and apoptosis compared to the sham-operation group. The expression of Caspase-3 and Bax turned out to be strengthened by T/ D and relatively decreased with GYY4137 treatment in both the G-IP and G-IT groups. Moreover, the Bcl-2 expression was inhibited in the T/D group, and promoted by GYY4137 in the G-IP and G-IT groups. GYY4137, moderating these observed changes, displayed a more protective effect with G-IT therapy than G-IP therapy.This study indicated that the efficacy of intratesticular therapy with GYY4137 is better than that of intraperitoneal therapy, which may provide a more valuable approach for testicular torsion therapy.

Monozygotic Twins Suffering From Sodium Taurocholate Cotransporting Polypeptide Deficiency: A Case Report.

Sodium taurocholate cotransporting polypeptide (NTCP) is a carrier protein encoded by the human SLC10A1 gene, acting as the principal transporter of conjugated bile salts from the plasma into hepatocytes. Although NTCP was cloned as early as in 1994 and its function has been studied extensively, clinical description of NTCP deficiency remains rather limited thus far. The patients in this paper were 2 female monozygotic twins, who were referred to our hospital at the age 2 years with the complaint of persistently-raised total bile acids (TBA) for 21 months. At age 3 months, they were both diagnosed to have cholestatic liver disease due to raised serum TBA and direct bilirubin (DBIL) with the fraction >20% of the elevated total bilirubin (TBIL). Thereafter, their jaundice subsided and the DBIL levels recovered gradually, while serum TBA remained raised persistently. In view of their refractory hypercholanemia but negative symptoms and signs, SLC10A1 genetic analysis was performed for all family members to evaluate the possibility of NTCP deficiency. As a result, the twins were both homozygotes, while the parents, carriers, of the reportedly pathogenic variant c.800C>T (p.Ser267Phe). These findings suggested that NTCP deficiency may be a unique genetic factor causing transient cholestasis in early infancy, as well as, persistent hypercholanemia in pediatric patients.

Analysis of thermo-optic effect-based refractive index dynamic modulation in microspherical resonator.

The thermo-optic effect has been utilized to modulate the refractive index dynamically within a whispering gallery mode resonator. Modulation with a large tuning range is mostly performed for mode locking and dynamic control of the optical path at a modulation frequency as low as several hertz, while high-frequency modulation up to megahertz is mainly exploited in optical switching devices with small tuning range. Here, we introduce the response functions theoretically to describe the dynamic response of temperature changes in the mode volume and the resonator body, respectively. This result is verified experimentally in silica microspherical resonators. The dependence of the tuning range on the modulation frequency is achieved. This knowledge could pave the way toward more practical control of refractive index in microresonators.

In vivo reversion of an inherited mutation in a Chinese patient with Wiskott-Aldrich syndrome.

A spontaneous reversion that restores Wiskott-Aldrich syndrome protein (WASP) expression was reported recently. However, the genetic mechanism underlying the reversion event was unclear. In the present study, a WAS patient with a nonsense mutation (155 C>T, R41X) was followed during a three-year period. No expression of WASP was detected in peripheral blood mononucleated cells (PBMCs) in 2009 and a small population of intracellular WASP positive lymphocytes was detected during the following three years. The increasing trend of the revertant genotype was significant. WASP-expressing cells were present mainly CD56+ NK cells and CD8+ T cells. Sorted WASP+ cells were analyzed, indicating that the population of CD3+ T cells increased from 36.81% to 99.8%. Although the revertant cells in vivo may have a growth advantage, the patient presented a persistent autoimmune disease, thrombocytopenia, and died from extensive pulmonary fibrosis. The results suggest that the clinical consequences of T-cell mosaicism in WAS remain difficult to predict and is not sufficient to fully normalize immune functions in patients with WAS.

[Treatment of sludge liquor produced in deep dehydration by photoelectro-Fenton process].

Photoelectro-Fenton process was developed to treat the sludge liquor produced in deep dehydration. The results indicated that pollutants could be removed efficiently from the sludge liquor. Under the optimum condition of pH 3.0, H2O2 concentration of 65.3 mmol x L(-1), FeSO4 concentration of 6.53 mmol x L(-1) [ n(Fe2+): n (H2O2) = 1:10], 7.5V, the COD removal efficiency reached 59.0 % after 20 min treatment. The removal efficiency of TOC, TN, NH: -N and TP could reach 49. 3% , 20. 6% , 73.6% and 96.5% , respectively. This study would provide the reference for photoelectro-Fenton process in real wastewater treatment.

Chitin microfibers reinforce soy protein gels cross-linked by transglutaminase.

To improve the gel strength, we attempt to introduce the microcomposite concept into the food gel system. A stable positively charged chitin microfibers (CMFs) suspension was fabricated by a facile microfluidizer approach without changing its chemical structure. The obtained CMFs bearing width of about 0.5-5 µm and length of more than 500 µm were then developed in a transglutaminase cross-linked ß-conglycinin (7S) gel. The morphological and rheological characterizations of the 7S-CMF composited gels were done as a function of the protein and CMFs concentrations. Results showed that the presence of the CMFs network improved the gel strength significantly. This effect was CMFs content dependent and was related to the formation of a sponge-like porous microstructure. We inferred that the CMFs provided an initial framework for gel formation and added structural rigidity to the protein gel. The role of protein was to participate in network development as an electrostatic coating and gelation component.

Transport properties of dense deuterium-tritium plasmas.

Consistent descriptions of the equation of states and information about the transport coefficients of the deuterium-tritium mixture are demonstrated through quantum molecular dynamic (QMD) simulations (up to a density of 600 g/cm(3) and a temperature of 10(4) eV). Diffusion coefficients and viscosity are compared to the one-component plasma model in different regimes from the strong coupled to the kinetic one. Electronic and radiative transport coefficients, which are compared to models currently used in hydrodynamic simulations of inertial confinement fusion, are evaluated up to 800 eV. The Lorentz number is discussed from the highly degenerate to the intermediate region. One-dimensional hydrodynamic simulation results indicate that different temperature and density distributions are observed during the target implosion process by using the Spitzer model and ab initio transport coefficients.

Clinical characteristics and mutation analysis of X-linked severe combined immunodeficiency in China.

UNLABELLED: X-linked severe combined immunodeficiency (X-SCID) is a rare, life-threatening immune disorder, caused by mutations of the gene for the γ-chain (γc) of the interleukin-2 receptor, IL2RG. We analyzed the clinical, immunologic, and molecular characteristics of children with X-SCID, attempting to improve the diagnosis and treatment of X-SCID in China. METHODS: X-SCID was suspected in male infants with recurrent or persistent infections. Eleven male infants from ten unrelated Chinese families were included. The IL2RG gene was amplified and sequenced, followed by mutation analysis in these children and their female relatives. X-linked short tandem repeat (X-STR) typing was done to define the maternal lymphocyte engraftment. RESULTS: The 11 children exhibited recurrent infections and 10 of them had lymphopenia. B cells were present in all patients, T cells were markedly reduced in 10, and NK cells were markedly reduced in 9. Nine IL2RG gene mutations were identified in the 11 children, with 5 novel mutations. One patient was found to have the maternal lymphocyte engraftment. CONCLUSION: The clinical presentations and immunologic characteristics of the X-SCID patients were accordingly quite uniform despite the heterogeneity of mutations locating almost in the entire γc gene.

[FCGR3B gene frequencies and FCGR3 gene variants in Chinese: a study in 487 Chinese individuals from Zhejiang Province].

OBJECTIVE: To investigate the FCGR3B gene frequencies and FCGR3 variants in a Chinese population from Zhejiang Province. METHODS: DNA was extracted from the blood specimens of 487 healthy blood donors from Zhejiang Province. The FCGR3B gene frequencies were determined by polymerase chain reaction with sequence-specific primers (PCR-SSP). The 19 specimens with 3 different FCGR3B genotypes underwent FCGR3 gene cloning and sequencing. RESULTS: The gene frequencies of FCGR3B(*1), FCGR3B(*2), and FCGR3B(*3) in these 487 individuals were 0.564, 0.429, and 0.000 respectively. The genotype frequency of FCGR3B(null) was 0.62% (3/487). Sequencing of FCGR3 revealed that in 7 out of the 19 Chinese individuals variants caused by single nucleotide exchanges at one or more of the polymorphic positions 141, 147, 227, 266 and 277 in exon 3 also existed in this Chinese population. CONCLUSION: FCGR3B(*1) gene is more frequent in a Chinese population from Zhejiang Province than the FCGR3B(*2) gene, and the FCGR3B(*3) gene seems to be absent. Gene variants caused by single nucleotide exchanges are found in addition to the well known forms, but the reason for this remains unclear.