Cycle oxidation behavior and anti-oxidation mechanism of hot-dipped aluminum coating on TiBw/Ti6Al4V composites with network microstructure.

Controlled and compacted TiAl3 coating was successfully fabricated on the network structured TiBw/Ti6Al4V composites by hot-dipping aluminum and subsequent interdiffusion treatment. The network structure of the composites was inherited to the TiAl3 coating, which effectively reduces the thermal stress and avoids the cracks appeared in the coating. Moreover, TiB reinforcements could pin the TiAl3 coating which can effectively improve the bonding strength between the coating and composite substrate. The cycle oxidation behavior of the network structured coating on 873 K, 973 K and 1073 K for 100 h were investigated. The results showed the coating can remarkably improve the high temperature oxidation resistance of the TiBw/Ti6Al4V composites. The network structure was also inherited to the Al2O3 oxide scale, which effectively decreases the tendency of cracking even spalling about the oxide scale. Certainly, no crack was observed in the coating after long-term oxidation due to the division effect of network structured coating and pinning effect of TiB reinforcements. Interfacial reaction between the coating and the composite substrate occurred and a bilayer structure of TiAl/TiAl2 formed next to the substrate after oxidation at 973 K and 1073 K. The anti-oxidation mechanism of the network structured coating was also discussed.

[Clinical experience of 302 cases with brain abscess].

Objective: To compare the diagnosis and treatment experience of brain abscesses and improve prognosis. Methods: The data of 302 patients of brain abscess at Department of Neurosurgery in Tianjin Medical University General Hospital from 1980 to 2014 was analyzed retrospectively. There were 215 male and 87 female patients aged from 11 to 82 years with mean age of (30±8) years. The patients was divided into 1980-2001 group and 2002-2014 group according to different diagnosis and the treatment methods. The therapy methods include operation and conservative treatment. There were 196 cases received operation, including 95 cases of excision, 89 cases of ventriculopuncture, 12 cases of excision after ventriculopuncture, 106 cases received drug conservative therapy. Two groups of information including clinical manifestation, abscess location, therapeutic effect and prognosis were compared by χ(2) test. Results: Compared to 1980-2001 group, adjacent infection incidence declined(χ(2)=8.000, P=0.005). The ratio of single abscess declined and multiple abscess increased(χ(2)=11.060, P=0.001), the infection proportion of frontal lobe and temporal lobe decreased(χ(2)=9.080, P=0.003; χ(2)=15.440, P=0.000). The ratio of headache and vomit and papilledema declined significantly(χ(2)=23.290, P=0.000; χ(2)=21.020, P=0.000; χ(2)=2.290, P=0.001). Total mortality of 302 patients were 23 cases and 5 cases of 1980-2001 group and 2002-2014 group (10.4% vs. 6.3%, χ(2)=1.180, P=0.277). However, there were statistical difference in postoperative mortality between both groups (14.4% vs. 4.0%, χ(2) =3.880, P=0.049). Conclusion: With the application of antibiotics and the development of neurosurgical techniques, the prognosis of brain abscess has been improved.

Diagnostic value of cytological and microbiological methods in cryptococcal meningitis.

The aim of this study was to investigate diagnostic methods for cryptococcal meningitis (CM). A retrospective analysis was conducted for 31 patients with CM confirmed by etiologic detection of cerebrospinal fluid in our hospital in the past 5 years. Nineteen cases in 31 patients were confirmed with CM in the first diagnosis, with a misdiagnosis rate of 38.7%. The positive rates of cryptococcus detection in cerebrospinal fluid with May-Grünwald-Giemsa (MGG)-, ink-, and Alcian blue-staining methods were 86.9, 70.9, and 80.6%, respectively. The misdiagnosis rate of CM is high during the early stage of disease. The total positive rate of cryptococcus diagnosis using the MGG-staining method was significantly higher than that using the ink-staining method. These results are important for diagnosing CM.

Molecular changes of mesenchymal stromal cells in response to dexamethasone treatment.

BACKGROUND: Mesenchymal stem cells (MSCs) are multipotent stromal cells that can differentiate into a variety of cell types. The MSCs can be activated and mobilized if needed. AIM: This study aimed to investigate the response mechanism of MSCs under Dexamethasone (Dex) treatment by combining MSCs microarray and bioinformatics methods. MATERIALS AND METHODS: We downloaded the gene expression profile of rat's MSCs challenge with or without Dex (GSE3339) from Gene Expression Omnibus database, including 2 Dex treated samples and 3 untreated samples. The differentially expressed genes (DEGs) were identified by packages in R language. Then, Gestalt (Genomic Sequence Total Analysis and Lookup Tool) and EASE (Expression Analysis Systematic Explorer) to were employed to obtain the molecular events of MSCs under Dex treatment. RESULTS: A total of 17 genes were identified as DEGs between untreated and treated samples, and they were significant enriched in immune response and cell differentiation. The C3 gene was the common candidate gene selected from two different algorithms, and 24 conserved sites were identified in the 3'UTR of C3 gene. CONCLUSIONS: Genes associated with immune response and cell differentiation were dysregulated in MSCs under Dex.

Marek's disease virus latent protein MEQ: delineation of an epitope in the BR1 domain involved in nuclear localization.

Marek's disease virus latent protein MEQ (MDV Eco Q) is abundantly expressed and consistently detected in MDV-induced tumors and cell lines. Deletion mutants were constructed to study the domain structure of MEQ. Four deletion mutants were obtained in the basic regions of MEQ, namely basic region 1 (DeltaBR1), basic region 2 (DeltaBR2), basic regions 1 and 2 (DeltaBR1 and 2), and the C-terminal (bZIP) domain. The BR1 and BR2 are nuclear localization signals and either is sufficient to cause transport of MEQ into the nucleus. In addition, the BR2 is also responsible for MEQ's nucleolar localization. A monoclonal antibody (Mab 23B46) was produced using recombinant fowlpox virus (rFPV) expressing MEQ (rFPV/MEQ) as a source of protein. The isotype of Mab 23B46 is IgG1 and immunoprecipitated a band in rFPV/MEQ infected cells with molecular weight of 60 kDa specific to MEQ protein. We detected abundant expression of MEQ in (rFPV/MEQ), recombinant baculovirus (rBac) (rBac/MEQ), and lymphoid tumors induced by MDV. In order to delineate the epitope of MEQ reactive with Mab 23B46, we used four deletion mutants from the basic and bZIP domains. We found the deletions in the N-terminal region including BR1 (DeltaBR1), and (DeltaBR1 and 2) completely abolished the specific binding with Mab 23B46 as shown by Western blot analysis and immunofluoresence test. Deletion of BR2 (DeltaBR2) and the C-terminal (bZIP) domain had no effect on antibody binding. These data provide direct evidence that monoclonal antibody reactive epitope is localized in the BR1 domain of the molecule. Since both BR1 and BR2 domains contain sequences important for nuclear entry, we now have reagent to further study and elucidate the mechanism of MEQ's involvement in nuclear and nucleolar localization.