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Novel hybrid magnetic cross-linked enzyme aggregates of phenylalanine ammonia lyase (HM-PAL-CLEAs) were developed by co-aggregation of enzyme aggregates with magnetite nanoparticles and subsequent crosslinking with glutaraldehyde. The HM-PAL-CLEAs can be easily separated from the reaction mixture by using an external magnetic field. Analysis by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) indicated that PAL-CLEAs were inlayed in nanoparticle aggregates. The HM-PAL-CLEAs revealed a broader limit in optimal pH compared to free enzyme and PAL-CLEAs. Although there is no big difference in Km of enzyme in CLEAs and HM-PAL-CLEAs, Vmax of HM-PAL-CLEAs is about 1.75 times higher than that of CLEAs. Compared with free enzyme and PAL-CLEAs, the HM-PAL-CLEAs also exhibited the highest thermal stability, denaturant stability and storage stability. The HM-PAL-CLEAs retained 30% initial activity even after 11 cycles of reuse, whereas PAL-CLEAs retained 35% of its initial activity only after 7 cycles. These results indicated that hybrid magnetic CLEAs technology might be used as a feasible and efficient solution for improving properties of immobilized enzyme in industrial application. [ABSTRACT FROM AUTHOR]

Novel hybrid magnetic cross-linked enzyme aggregates of phenylalanine ammonia lyase (HM-PAL-CLEAs) were developed by co-aggregation of enzyme aggregates with magnetite nanoparticles and subsequent crosslinking with glutaraldehyde. The HM-PAL-CLEAs can be easily separated from the reaction mixture by using an external magnetic field. Analysis by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) indicated that PAL-CLEAs were inlayed in nanoparticle aggregates. The HM-PAL-CLEAs revealed a broader limit in optimal pH compared to free enzyme and PAL-CLEAs. Although there is no big difference in Km of enzyme in CLEAs and HM-PAL-CLEAs, Vmax of HM-PAL-CLEAs is about 1.75 times higher than that of CLEAs. Compared with free enzyme and PAL-CLEAs, the HM-PAL-CLEAs also exhibited the highest thermal stability, denaturant stability and storage stability. The HM-PAL-CLEAs retained 30% initial activity even after 11 cycles of reuse, whereas PAL-CLEAs retained 35% of its initial activity only after 7 cycles. These results indicated that hybrid magnetic CLEAs technology might be used as a feasible and efficient solution for improving properties of immobilized enzyme in industrial application. [ABSTRACT FROM AUTHOR]

LiCl is a kosmotrope that generally promotes protein salvation in aqueous solutions. Herein we report that LiCl embedded in electrospun polymeric nanofibers interestingly induced an abnormal protein adsorption and substantially augmented the adsorption capacity of the fibers. As a result, equilibrium protein loadings reached over 64% (w/w) of the dry mass of fibers, 9-fold higher than that observed in the absence of the salt. The adsorption appeared to be irreversible such that little protein loss was observed even after washing the fibers vigorously with fresh buffer solutions. We further examined the application of such intensified protein adsorption for enzyme immobilization. Proteins including bovine serum albumin (BSA) and protamine were first adsorbed, followed by covalent attachment of an outer layer of an enzyme, α-chymotrypsin. Such a multilayer-structured nanofibrous enzyme exhibited extremely high stability with no obvious activity loss even after being incubated for 8 months at 4 °C in aqueous buffer solution. The LiCl induced irreversible protein adsorption, which has been largely ignored in previous studies with electrospun materials, rendering an interesting scenario of interfacial protein-material interactions. It also reveals a new mechanism in controlling and fabricating molecular interactions at interfaces for development of a broad range of biomaterials.

Objective: To study the changes of T-Lymphocyte and activated T-Lymphocyte subsets in influenza A (H1N1) virus patients., Methods: The percentages of the subsets of Lymphocyte were detected by flow cytometry in influenza A (H1N1) virus patients (n = 144) and normal controls (n = 41). Furthermore, the subsets of T-Lymphocyte and activated T-lymphocyte were analyzed in 83 among those patients before and after treatment., Results: Compared with the control group, the counts of Lymphocyte in patients with influenza A (H1N1) virus was significantly discreased, the counts of Lymphocyte in patients with influenza A virus concurrent pneumonia was significantly discreased those of no concurrent pneumonia; Compared with the control group, the percentage of T-lymphocyte in patients with influenza A virus concurrent pneumonia was significantly discreased. The counts and percentage of CD3 and CD8 cells was significantly discreased in patients (n = 83) before treatment; The counts of CD4 cells was significantly discreased before treatment. The percentage of HLA-DR+ CD+, HLA-DR+ CD4+ and HLA-DR+ CD8+ cells was significantly discreased in patients (n = 83) before treatment., Conclusions: To understand the expression of the T-Lymphocyte and activated T-Lymphocyte subsets in influenza A (H1N1) virus patients may help to evaluate the patients' cellular immune status, but also be a guideline of early diagnosis of Influenza A (H1N1) virus.

Objective: To investigate the expression of CD95 and special marker for activation of peripheral blood lymphocytes in patients with hand foot and mouth disease (HFMD) and its significance., Methods: Immunofluorescent two-color flow cytometry was used to study the expression of CD95 and HLA-DR on lymphocytes in 58 patients with HFMD and 34 normal controls., Results: Expression of CD3+ T cells was significantly lower in patients (63.82 +/- 7.74)% than that in controls (P < 0.001), meanwhile the expression of CD4+ T cells was (34.29 +/- 7.33)%, significantly lower than that of the controls (P < 0.005). The percentage of lymphocytes expressing HLA-DR in patients was (23.77 +/- 5.78)%, significantly higher than that of the controls (P < 0.005). Significant difference was observed in the expression of HLA- DR on CD8+ T cells in patients (1.34 +/- 1.12)% as compared with controls (P < 0.005). No significant difference in the expression of CD95 on lymphocytes was observed between patients and the controls (P > 0.05)., Conclusion: The findings support that cellular immunodeficiency exists in patients and that lymphocytes were abnormally activated in the patients. The activation of peripheral blood T lymphocytes in patients mainly involves CD8 subset and it may play an important role in the immune response to antiviral infection.