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SRPX2 (Sushi repeat-containing protein, X-linked 2) has recently emerged as a multifunctional protein that is involved in seizure disorders, angiogenesis and cellular adhesion. Here, we analyzed this protein biochemically. SRPX2 protein was secreted with a highly post-translational modification. Chondroitinase ABC treatment completely decreased the molecular mass of purified SRPX2 protein to its predicted size, whereas heparitinase, keratanase and hyaluroinidase did not. Secreted SRPX2 protein was also detected using an anti-chondroitin sulfate antibody. These results indicate that SRPX2 is a novel chondroitin sulfate proteoglycan (CSPG). Furthermore, a binding assay revealed that hepatocyte growth factor dose-dependently binds to SRPX2 protein, and a ligand–glycosaminoglycans interaction was speculated to be likely in proteoglycans. Regarding its molecular architecture, SRPX2 has sushi repeat modules similar to four other CSPGs/lecticans; however, the molecular architecture of SRPX2 seems to be quite different from that of the lecticans. Taken together, we found that SRPX2 is a novel CSPG that is overexpressed in gastrointestinal cancer cells. Our findings provide key glycobiological insight into SRPX2 in cancer cells and demonstrate that SRPX2 is a new member of the cancer-related proteoglycan family.

We report on the fabrication and nanoscale luminescence characteristics of an isolated rubrene single nanoparticle (NP). A solvent-vapor annealing process changed pristine rubrene NPs, prepared by a reprecipitation method, to perfect crystalline NPs. The formation and structural properties of crystalline and non-crystalline rubrene NPs were studied through SEM, HR-TEM, and X-ray diffraction experiments. The nanoscale photoluminescence (PL) characteristics and the luminescence color of the rubrene single NP were measured using a high-resolution laser confocal microscope with color charge-coupled device images. In comparison with the pristine rubrene NPs, the crystalline NPs exhibited highly bright and sharp light emission. The main PL peak at 561–562 nm for the crystalline rubrene single NP had a relatively narrow line-width and became more dominant through a solvent-vapor annealing. The enhanced and sharp light emission of the crystalline rubrene single NP originated from the strong π–π interaction of rubrene molecules along the major crystalline axis in the nano-sized structure.

Abstract 4878 Introduction According to international uniform response criteria for multiple myeloma suggested in 2006, the response assessment for patients with oligo- and non-secretory multiple myeloma (MM) can be evaluated by the serum free light chain (FLC) assay. Although the FLC response criteria are not applicable in MM patients with measurable disease, there were several reports suggesting that serial measurement of serum FLC may detect relapse earlier than protein electrophoresis studies. We, therefore, investigated the preceding changes in serial serum FLC assay until progressive disease was confirmed by the international uniform response criteria in post-ASCT patients with measurable disease. Patients and Method We included patients from the AMC MM transplant registry, who met the following (1) undertook ASCT for measurable disease (2) showed, at least, two serial response assessment of stable disease or complete response before progression or relapse by serum or urine M-protein, (3) had periodic serum FLC assay simultaneously tested with serum and/or urine protein electrophoresis at each response assessment. Progressive disease (PD) was defined by increase of ≥ 25% from baseline in serum M-protein (the absolute increase must be ≥ 0.5mg/dL) and/or urine M-component (the absolute increase must be ' 200mg/24h) according to international uniform response criteria. In this investigation, significant increase in the difference between involved and uninvolved FLC (dFLC) and in the involved FLC (iFLC) was defined by increase of ≥ 25% from baseline. The positive predictive value of three cutoff levels for absolute increase, 10mg/L, 20mg/L, 100mg/L, were evaluated for both dFLC and iFLC provided serum FLC ratio was abnormal. Each patient was followed up with 1-3 month intervals according to the protocol for MM patients after ASCT. Result A total 29 patients of 138 patients in the AMC MM transplant registry satisfied above criteria. When the cut-off level for absolute increase was defined as 100mg/L, the significant increase of iFLC in 12 patients (41%) and dFLC in 11 patients (38%) preceded or accompanied with the time of progressive disease observed by M-protein. The median value of preceding time was 2 month (range -5 - 0). When the cut-off level was defined as 20mg/L, the sustained significant increase of iFLC in 21 patients (72%) and dFLC in 17 patients (59%) preceded or accompanied with the time of progressive disease with median of 2 month (range -9 - 0) and 2 month (range, -5 – 0), respectively. At the cut-off level of 10mg/L, the sustained significant increase of iFLC in 23 patients (79%) and dFLC in 21 patients (72%) preceded or accompanied with the time of progressive disease observed by M-protein. The median of preceding time was 2 month (range -11 - 0) and 1 month (range, -11 - 0), respectively. Twenty-eight dFLC values were observed as negative values out of a total 123 data from 29 patients. Of these values, 12 were below normal iFLC concentration, 14 within normal range of iFLC (kappa 8.5 - 23.7 mg/L, lambda 9.5 - 23.5 mg/L), and 2 above normal iFLC concentration. Conclusion In this study, about 70% of patients showed sustained significant increase of iFLC that preceded or accompanied the time of progressive disease observed by M-protein by a median of 2 months at a cut-off absolute increase of 20mg/L. Although there is a subtle difference in prediction rates according to defined cut-off levels, serial follow up of iFLC and sustained increase by 25% during follow-up seems to have a utility in the prediction of progression after ASCT. In addition, interpretations of dFLC may be difficult as it is frequently observed as negative value in post-ASCT MM patients. Therefore, the serial and sustained increase of iFLC may be useful in lower iFLC concentrations. However, there should be more validation with large patients' population. Disclosures No relevant conflicts of interest to declare.

Abstract 5013 Introduction Primary mediastinal large B-cell lymphoma (PMBCL) was formally established as a distinct subtype of diffuse large B-cell lymphoma (DLBCL). Some studies indicated that patients with PMBCL have an aggressive clinical course with short median survival but more recent studies reported a relatively good response rate and survival. Therefore, controversies still exist regarding the response to therapy and prognosis of patients with PMBCL. Patients and methods Between July 1993 and July 2008, a total of 26 patients with PMBCL were identified at Asan Medical Center, Seoul Korea. We retrospectively reviewed the clinic-pathologic features and clinical outcomes of them in comparison with 597 patients diagnosed with non-mediastinal DLBCL during the same period. Result Out of the 26 patients, 17 (65.4%) were females and 9 (34.6%) males, while out of the 597 patients, 257 (43.0%) were females and 340 (57.0%) males (p=0.025). The median age of the PMBCL patients was 31.5 years old (range 15-78 years old), while that of the DLBCL patients was 56.0 years old (range 15-85 years old). Out of the 26 patients, 14 (53.8%) had a Ann Arbor stage III or IV disease, 7 (26.9%) had B symptoms, and by the IPI, 11 were in low, 9 in low intermediate, 2 in high-intermediate and 4 in high risk group. Out of 24 patients treated with front-line therapy CHOP or R-CHOP, 17 (70.8%) reached a CR, while 1 PR patient reached a CR after being treated with high-dose chemotherapy followed by autologous stem cell transplantation. Five refractory patients were treated with high-dose chemotherapy followed by autologous stem cell transplantation, but among them only one reached a CR and 4 died of disease progression. With a median follow-up of 41.5 months (range 1-92 months), 5-year survival rates of PMBCL and non-mediastinal DLBCL patients were 69% and 65.7%, respectively (p=0.982, Log Rank). Conclusion There was no difference between PMLBL and non-mediastinal DLBCL in terms of clinical features and outcomes. Disclosures No relevant conflicts of interest to declare.

Abstract 2939 Poster Board II-915 Introduction: Peripheral blood absolute lymphocyte count (ALC) at the time of diagnosis is a prognostic indicator in hematologic malignancies. However, no reports have addressed whether ALC at the time of first relapse (ALC-R) has a prognostic significance in the patients with relapsed T-cell Non-Hodgkin's lymphoma (NHL). We retrospectively studied the prognostic significance of ALC-R in these patients. Patients and Methods: We identified 63 patients who had a documented relapsed disease after having reached a complete response, including at least an unconfirmed complete response between 1993 and 2007 and we analyzed their ALC-R and following variables at the time of first relapse; age, gender, the number of extranodal sites, lactate dehydrogenase, ECOG performance status, stage and international prognostic index. Results: Out of the 63 patients, 23 (36.5%) had a peripheral T-cell lymphoma, not otherwise characterized, while 15 (23.8%) had an extranodal NK/T-cell lymphoma, nasal type, 6 (9.5%) anaplastic large-cell lymphoma, 5 (7.9%) angioimmunoblastic T-cell lymphoma, 2 (3.2%) primary cutaneous T cell lymphoma and 12 (19%) other types. Among them, 32 (50.8%) had an ALC-R ≥ 1.25 × 109/L, 47 (74.6%) had an ECOG PS 0 or 1 and by IPI at relapse, 0, 1, 2, 3, 4, and 5 were 20.6%, 25.4%, 23.8%, 23.8%, 4.8%, and 1.6%, respectively. Univariate analyses showed that good ECOG PS (HR, 0.408; 95% CI 0.190-0.876; p=0.022) and high ALC at relapse (HR, 0.394; 95% CI 0.210-0.740; p=0.004) were associated with longer survival from relapse ( Table 1 ). Multivariate analysis also showed that high ALC at relapse (HR, 0.369; 95% CI 0.187-0.726; p=0.004) and good ECOG PS (HR, 0.295; 95% CI 0.131-0.666; p=0.003) were still associated with longer survival outcome ( Table 2 ). Conclusions: The high ALC-R predicted a better prognosis in patients with relapsed T-cell NHL, suggesting that the host immune system might have a crucial role. Table 1 . Univariate Cox proportional hazard model Variables Hazard Ratio HR 95 % CI P-value ALC-R ≥1.25 × 109/L 0.394 0.210-0.740 0.004 1 Age, years >60 1.310 0.669-2.564 0.431 '60 1 Gender women 0.994 0.523-1.890 0.986 men 1 the number of extranodal sites >1 1.312 0.605-2.846 0.491 '1 1 LDH abnormal 1.545 0.813-2.937 0.184 normal 1 ECOG PS 0, 1 0.408 0.190-0.876 0.022 ≥2 stage III, IV 1.462 0.795-2.688 0.221 I, II 1 IPI ≥3 1.191 0.618-2.296 0.602 1 Table 2 . Multivariate Cox proportional hazard model Variables Hazard Ratio HR 95% CI P-value High ALC-R (≥1.25 × 109/L) 0.369 0.188-0.726 0.004 Good ECOG PS (0, 1) 0.295 0.131-0.666 0.003 Disclosures: No relevant conflicts of interest to declare.

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Department of Bioscience and Biotechnology, Sejong University, Seoul 143-747(Received 1 September 2006)During immune responses, macrophages play important roles in phagocytosis and antigen presen-tation by engulfing pathogenic micro-organisms and cell debris. Since the function of a macrophagehighly depends on a series of physical steps including migration, direct contact and strong bindingto its target, deployment of cytoplasm and membrane, and intake of the target, here we have inves-tigated the mechanical behavior of a macrophage by manipulating it with a flexible pipette that wasused as a force sensor and transducer. We examined the response of a macrophage to mechanicalpulling by a positively charged pipette. We observed that the macrophage initially formed strongbinding to the pipette and migrated along the direction of pulling for some early period. Afterthat period, the macrophage exerted a huge traction force to pull the pipette back and attemptedto retract itself towards its original location. We found that whether it was able to return to theoriginal location depended on the level of applied force. Since the traction force generated by asingle macrophage had not been characterized accurately, we measured the force for the first timeto our knowledge and found the maximum traction force to be around 80 nN. This quantitativemeasurement was made possible by a new and convenient method used to calibrate the stiffness ofthe pipette. Through the study, we acquired a better understanding of the mechanics of and theforce generation by a macrophage.

We report that polydiacetylenes (PDAs) vesicles were successfully immobilized and chemisorbed on single crystal ZnO surfaces. Immobilized PDAs on ZnO were found to be sensitive to temperature and selectively sensitive to α- and γ-cyclodextrins. This approach is attractive for the on-chip integration of various types of sensors, ultraviolet light emitting diodes, and transparent electronics with PDAs.

Elastomeric stamps with micrometer-sized grids are fabricated for building biological cell networks by design. Polymerized polydimethyl-siloxane (PDMS) stamps are cast in a variety of different molds prepared by micro-electro mechanical systems (MEMS) technology. Micro square-grid patterns of 3-aminopropyl triethoxy silane (APS) are successfully imprinted on glass plates, and patterned networks of cardiac cells are obtained as designed. The resulting cellular networks clearly demonstrate that cell attachment and growth are greatly favored on APS-treated thin tracks. Here, we report the technical details related to the fabrication of microstamps, to the stamping procedure, and to the culture method. The potential applications of patterned cellular networks are also discussed.

The I-picture starting time distribution of variable bit rate (VBR) MPEG video sources may significantly affect the cell loss characteristics of ATM multiplexers. The authors propose a new connection admission control (CAC) method which can reflect this effect. For CAC, VBR MPEG video traffic is modelled as a composite sequence of three subsequences with different effective bandwidths according to their picture coding types. Experimental results show that the proposed method can fully reflect this effect due to the starting time distribution while also improving network utilisation significantly.