Molecular characterization of complete and incomplete immunoglobulin heavy chain gene rearrangements in hairy cell leukemia.

PURPOSE: We analyzed patients with hairy cell leukemia (HCL) to achieve a better understanding of the differentiation stage reached by HCL cells and to define the key role of the diversification of cell surface makers, especially CD25 expression. PATIENTS AND METHODS: We analyzed 38 previously untreated patients with HCL to characterize their complete (VDJ(H)) and incomplete (DJ(H)) immunoglobulin (Ig) heavy chain (IgH) rearrangements, including somatic hypermutation pattern and gene segment use. RESULTS: A correlation between immunophenotypic profile and molecular data was seen. All 38 cases showed monoclonal amplifications: VDJ(H) in 97%, DJ(H) in 42%, and both in 39%. Segments from the D(H)3 family were used more in complete compared with incomplete rearrangements (45% vs. 12%; P <.005). Furthermore, comparison between molecular and immunophenotypic characteristics disclosed differences in the expression of CD25 antigen; CD25(-) cases, a phenotype associated with HCL variant, showed complete homology to the germline in 3 of 5 cases (60%), whereas this characteristic was never observed in CD25(+) cases (P <.005). Moreover, V(H)4-34, V(H)1-08, and J(H)3 segments appeared in 2, 1, and 2 CD25(-) cases, respectively, whereas they were absent in all CD25(+) cases. CONCLUSION: These results support that HCL is a heterogeneous entity including subgroups with different molecular characteristics, which reinforces the need for additional studies with a larger number of patients to clarify the real role of gene rearrangements in HCL.

Characterization of High-Performance Organic Dyes for Dye-Sensitized Solar Cell: A DFT/TDDFT Study

Dye-sensitized solar cell (DSSC) is currently a promising technology that makes solar energy efficient and cost-effective to harness. In DSSC, metal free dyes, such indoline-containing D149 and D205, are proved to be potential alternatives for traditional metal organic dyes. In this work, a DFT/TDDFT characterization for D149 and D205 were carried out using different functionals, including B3LYP, MPW1K, CAM-B3LYP and PBE0. Three different conformers for D149 and four different conformers for D205 were identified and calculated in vacuum. The performance of different functionals on calculating the maximum absorbance of the dyes in vacuum and five common solvents (acetonitrile, chloroform, ethanol, methanol, and THF) were examined and compared to determine the suitable computational setting for predicting properties of these two dyes. Furthermore, deprotonated D149 and D205 in solvents were also considered, and the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) were calculated, which elucidates the substitution effect on the rhodanine ring of D149 and D205 dyes on their efficiency. Finally, D149 and D205 molecules were confirmed to be firmly anchored on ZnO surface by periodic DFT calculations. These results would shed light on the design of new highly efficiency metal-free dyes.

Preparation and characterization of Pr0.6Sr0.4FeO3-δ-Ce0.9Pr0.1O2-δ nanofiber structured composite cathode for IT-SOFCs

In this work, Pr_0.6Sr_0.4FeO_3-δ -Ce_0.9Pr_0.1O_2-δ (PSFO-CPO) nanofibers were synthesized by a one-step electrospin technique for use in intermediate-temperature solid oxide fuel cell (IT-SOFC) applications. PSFO-CPO nanofibers were produced with a diameter of about 100nm and lengths exceeding tens of microns. The thermal expansion coefficient (TEC) matches with standard GDC electrolytes and the resulting conductivity also satisfies the needs of IT-SOFCs cathodes. EIS analysis of the nanofiber structured electrode gives a polarization resistance of 0.072Ωcm² at 800°C, smaller than that from the powdered cathode with the same composition. The excellent electrochemical performance can be attributed to the well-constructed microstructure of the nanofiber structured cathode, which promotes surface oxygen diffusion and charge transfer processes. All the results imply that the one-step electrospin method is a facile and practical way of improving the cathode properties and that PSFO-CPO is a promising cathode material for IT-SOFCs.