Engraftment of heavily transfused patients with severe aplastic anemia with a fludarabine-based regimen.

We have developed a practical conditioning regimen without anti-thymocyte globulin (ATG), irradiation, or other myeloablative alkylating agent for low-income countries in which patients with severe aplastic anemia (SAA), who usually have heavily transfused and a prolonged disease history. The application of ATG, Busulphan, and/or irradiation to cyclophosphamide (Cy) to avoid graft rejection has many short- and long-term complications. In this study, we focused on evaluating a fludarabine-based conditioning regimen, among 83 patients with SAA. Patients were treated with fludarabine (40 mg/m(2) /d; day [-5 to -2]) and cyclophosphamide (50 mg/kg/d; day [-5 to -2]). Altogether, 81 patients indicated initial engraftment, whereas two cases showed primary graft failure. And four of the 81 cases indicated graft rejection during follow-up. Regardless of a high cumulative incidence of acute (55/83; 66.2% grade II-IV; 47/83; 56.6% III-IV) and chronic graft-versus-host disease (50/83; 60.2%), in total, 77 patients showed durable engraftment and transfusion independence, and 64 are alive at a median time of 49 months with an overall survival rate of 66%. In conclusion, this conditioning indicated well toleration, mild toxicity, durable engraftment, excellent survival as well as less cost. Its application might shed new light on SAA at high risk of graft rejection in resource-limited countries.

[Construction of P2Y6 constitutive knock down breast cancer cell line and evaluation of its proliferation].

AIM: To construct the constitutive P2Y6 knock down breast cancer cell line with shRNA technology and provide a basis for discovering how P2Y6 regulates tumorigenesis and progression in breast cancer. METHODS: The paired oligo nucleotides targeting human P2Y6 gene were synthesized and annealed into linear PLKO lentiviral vector digested by EcoRI and AgeI. The recombined vector which was identified by double digest with EcoRI and NdeI and DNA sequencing was packaged in 293T cells together with psPAX2 and pMD2.G. Virus in culture supernatant was concentrated, three recombinant vectors were transfected into BT549 cells, and the constitutive P2Y6 knock down cells were selected by puromycin. The efficiency of RNA interference was detected by RT-PCR and Western blotting. MTS assay was used to detect the influence of P2Y6 on breast cancer cells'proliferation. RESULTS: The inserted sequence was proven to be correct by DNA sequencing. After stable transfection of P2Y6 shRNA, the expression of P2Y6 in BT549 cells was decreased obviously in both protein and mRNA level. But no obvious influence on proliferation was found in P2Y6 gene knock down cells. CONCLUSION: The constitutive P2Y6 knock down cell line was successfully constructed in BT549 cells. Whereas, no obvious correlation was found between the expression of P2Y6 and breast cancer cell proliferation.

[Influence of K+ and Al3+ on the optical properties of Er3+ doped Sol-gel derived silica glasses].

Al3+ and K+ ions were introduced in Er(3+) -doped silica glass successfully through Sol-gel route. The optical characterizations including absorption spectra, transmission spectra, photofluorescence spectra, up-conversion spectra, Raman spectra and fluorescence decay lifetime were undertaken on the samples. The results show that not only the fluorescence intensity was strenthened by more than 20 and 70 times, but also the lifetime of Er3+ ions in Al(3+) -doped and K+ and Al(3+) -codoped samples was prolonged to 7.1 and 11.2 ms from 4.8 ms, respecticely. And by analysing the results, the authors concluded that the influences of Al3+ and K+ on Er3+ ions are completely different. And the authors found that Er3+ ions in silica glass may have two up-conversion mechanisms: two-phonon absorption and energy-transfer up-conversion using 980 nm excitation.

[Adhesion of oral microorganisms on dental porcelain polished and glazed].

OBJECTIVE: This study compared the roughness of porcelain polished or glazed surfaces and the adhesion of oral streptococcus mutans to them in vitro. METHODS: 30 porcelain samples were made. Porcelain samples in group A were polished with diamond paste. Porcelain samples were glazed in group B and were polished with Al2O3 (240#) bur in group C. Their roughness values were measured by profilometer. Standardized cell suspensions were incubated with test samples for one hour at 37 degrees C, then retained cells were counted by image analysis (percentage area of a microscopic field covered by cells). RESULTS: Roughness values of group A, B, C were respectively (0.1987 +/- 0.057) microm, (0.1990 +/- 0.091) microm, (0.4260 +/- 0.174) microm. There was no significantly difference between group A and group B. The roughness samples in group C were significantly rougher than that in the other groups. The amount of retained cells in group A, group B, group C was respectively (15.92 +/- 4.37)%, (16.39 +/- 6.31)% and (41.48 +/- 12.1)%. There was no significant difference between the cell adhesion on porcelain surface glazed and polished, but more bacteria adhered on the porcelain surface in group C. CONCLUSIONS: Porcelain surface polished treatment was clinically acceptable compared with its glazed. They all exhibited the least amount of bacteria adhesion. The more porcelain surface was rough, the more bacteria adhered on it.