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To develop monoclonal antibodies against the catalytic subunit of human telomerase hTERT for its expression detection of human tumors.A dominant epitope in hTERT (peptide hTERT(9))was automatically synthesized based on Fmoc method, and was used to immunize BALB/c mice. Hybridomas were generated and screened by ELISA for specific monoclonal antibodies, and the characterization of which were performed by Western blotting and immunohistochemical staining.Antigenic peptide hTERT(9) was synthesized and confirmed by MALDI-TOF-MS and HPLC analysis. Three hybridoma cell lines secreting anti-hTERT(9) antibodies designated as H4, G8 and A11 were established after primary screening and consequent three rounds of limited dilution. Both of H4 and G8 were IgM, while A11 was IgG1 in isotyping. The competitive assay showed that the antibodies were hTERT(9) specific, and the affinity of G8 was stronger than that of H4 and A11 assayed by affinity ranking. However, in Western blotting, both of H4 and G8 stained an about 123 000 protein band with HeLa and 293 cell extracts but not with normal 2BS cells. Besides, positive staining presented in the nucleus of HeLa, while 2BS was non-reactive immunohistochemically. The sections from paraffin-embedded blocks of 127 cases of human cancer, 40 of precancerous and 19 of benign tumors were in situ stained by G8 antibody, the results showed that the human cancer tissues were 80.31% (102/127) positive in specific nuclear reaction, on the contrary, only a minority of precancerous lesions present weak positive (17.5%, 7/40), and negative in benign tumors (0/19).The monoclonal antibodies developed against synthetic peptide were hTERT-specific and could recognize both the native and the denatured form. Thus their use in immunoblotting or immunohistochemistry for detecting the telomerase hTERT expression of cancer cell and tissues was promising.

The catalytic subunit of human telomerase reverse transcriptase (hTERT), is the necessary and rate-limiting component to telomerase activation in cancer cells. To develop monoclonal antibodies (MAbs) against hTERT, a peptide-hTERT(9)-derived from specific motif T of hTERT was synthesized. Through fusion of splenocytes of BALB/c mice immunized with hTERT(9) with mouse myeloma cells, hybridomas were generated and clones secreting anti-hTERT(9) antibody were screened. After three rounds of limited dilution of candidate clones, three of which present stable and constant antibody production. The MAbs were hTERT(9)-specific and reactive with native hTERT of human cancer cells or tissues in Western blot and immunohistochemistry. The heavy chain variable regions from three hybridomas were cloned and sequenced confirming their mouse Ig derivation. The described investigation suggested that the generated MAbs to hTERT(9) could recognize native hTERT and be useful to cancer research.

Chromatic induction from a surround is attenuated by chromatic contrast within a remote region outside of the surround (Shevell & Wei, 1998, Vision Research, 38, 1561-1566). The present study reports hue-cancellation measurements that show the attenuation depends on the magnitude, spatial frequency and chromaticity of remote chromatic contrast. Spatial-frequency tuning is shown by maximal attenuation of induction with remote contrast elements of the same size as the test. Experiments with various chromaticities of remote contrast show that S-cone stimulation within the remote region has a much weaker effect than L-/M-cone chromatic contrast, and does not depend on whether the S-cone stimulation is uniform or uneven across the region. Overall, the results show that remote L/M contrast affects classical chromatic induction, with its effect depending on the spatial frequency and magnitude of contrast. The influence of remote S-cone stimulation, on the other hand, is relatively weak and depends on only the S-cone spatial average, at least when S-cone stimulation by the test and its immediate surround is minimal (as in all experiments here).

We measured changes in color appearance caused by chromatic adaptation.

Objective: To evaluate response of homoharringtonine in patients with high risk AML or as a second-line therapy in patients with AML refractory to anthracycline based chemotherapy. Patients and methods: From Jan 1998-Jan 2006, there were 66 patients enrolled in this regimen. Male:female=40:26. Median age was 47 (17–69). There were 48 newly diagnosed AML, 5 relapsed AML and 13 secondary AML (secondary to MDS) in this group. Among these patients, there were 40 patients untreated previously — 20 patients had unfavourable chromasomal abmormalities, 10 patients had pgp positive, 10 patients had normal chromasome but high CD34 expression on leukemic cells. The remaining 26 patients were previously treated with daunorubincin or mitoxantrane combined with cytarabine at least two cycles and failed to achieve response. Homoharringtonine was given at dose of 4mg/m2/d(2.5mg/m2/d for age≥60 years) intraveniously for 7 days. Cytarabine was given at dose of 100mg/m2/d at same time. The therapy was repeated every 21 days.Post remission therapy was divided into two cohot —same regimen maintainance in 20 cases and cytarabine 1g/m2/d q12h for 4 days at least 4 cycles in 20 cases. Results: 40/66 patients achieved complete remission. 3/66 achieved partial remission. In patients refactory to anthracycline based regimen, the CR rate was 57.7%(15/26). In previously untreated high risk AML patients,the CR rate was 62.5%(25/40). Median disease free survival were 4.25 months (2–30) in cohot 1 and 18 months (12–47) in cohot 2 (P Conclusions: Homoharringtonine is effective in patients with high risk AML. It is also a choice of second line therapy in patients refractory to anthracycline based chemotherapy. Intensive post remission therapy is superior to conventional dose maintainance therapy in high risk AML. One of the ways for homoharringtonine to induce leukemic cell apoptosis is probably through Fas pathway.

Objective: Anthracycline-based chemotherapy induces 50%–70% of CR in patients with lymphoma, but only 30%–40% of long-term disease-free survival. Salvage chemotherapy with autologous stem cell rescue is required in patients with aggressive disease or never achieve CR with conventional chemotherapy,but the relapsed rate is still high. The purpose of this study was to evaluate radiotherapy post autologous stem cell transplantation in such group of patients. Methods: 15 patients who underwent autologous stem cell transplantation during 1992–1998 were enrolled in this study. Conditioning regimen was CBV (cyclophosphomide + carmustine + etoposide). Radiotherapy was started on day +50(31–90). All patients were followed up until January 2005. Kaplan-Mier survival analysis was made by using SPSS10.0 software. Results: There were 14 patients with non-Hodgkin lymphoma and 1 with Hodgkin disease enrolled. Male:female=11:4. Median age was 40 (30–64). At least 6 cycles of induction chemotherapy were given before transplantation. There were 3 patients in progression disease, 1 in stable disease, and 11 in partial remission before transplantation. Three patients received total lymph node irradiation (TLI). Seven patients received TBI(200cGY)+involved field irradiation therapy(IFIT). Five were treated with IFIT. All patients acheaved complete response(including 1 CRu) after radiotherapy. Three patients relapsed. One patient treated with TBI+IFIT relapsed at 6 months later. Two patients treated with IFIT relapsed at 8 and 36 months later respectively. The mean disease-free survival and overall survival were 10.84(SD1.37,95%CI) years and 11.89(SD1.35,95%CI) years respectively. The estimatrd 10-year disease-free survival and Overall survival were both 73%. One patient developed AML at 86 month. Grade III–IV hematologic toxicity was seen in 2 patients. Conclusions: Post ASCT radiotherapy is safe and tolerated. Relaps rate is low. Patients who received TLI or TBI+IFIT seem to have better outcome than that received IFIT only.

Peripheral blood hematopoietic stem cell transplantation has been replacing the bone marrow source stem cell transplantation for the treatment of hematological malignancies. Many efforts were made to enhance the stem cell number in peripheral blood and optimize the peripheral stem cell collection. Hematopoietic stem cell circles between bone marrow and peripheral blood during maturation. Thus the recruitment of hematopoietic stem cell in peripheral blood is a factor influencing the efficacy of peripheral blood stem cell apheresis. The aim of this study was to evaluate the effects of apheresis on the number of circulating stem cells. There were 41 consecutive cases involved. The mobilization regimen was chemotherapy + G-CSF. All patients underwent at least two apheresis. The volume of blood processed was calculated automatically by COBE Spectra cell separator. Blood samples were drawn just before each apheresis. CD34+ cells both in blood samples and in apheresis products were analyzed by multicolour flowcytometry. CFU-GM was cultured at same time. Data from the 1st and 2nd collection was compared. CD34+ /CD38− cells in peripheral blood increased from 48±12/ul to 133±40/ul (p Conclusions: Peripheral blood stem cell apheresis promotes stem cell recruitment in peripheral blood and increases circulating hematopoietic stem cells.

Chromatic induction from a surrounding light is measured with an additional remote field outside the surround. Chromatic induction from the surround into a central test field is found to be attenuated by a remote inhomogeneous `checkerboard', composed of squares at two different chromaticities. A uniform remote field, on the other hand, either at the average or at the most extreme chromaticity of the `checkerboard', has a weaker effect on chromatic induction than the inhomogeneous field, implying that chromatic contrast within the remote region is a critical factor. The complete set of experiments is accounted for by chromatic contrast gain control: chromatic induction, mediated by a neural signal for contrast at the edge of the test, is attenuated by contrast within the remote region. A contrast gain control set by variation in chromaticity over a broad area can contribute to the stable color appearance of surfaces embedded within complex scenes by minimizing chromatic induction from locally adjacent regions.