Experimental demonstration of energy-chirp control in relativistic electron bunches using a corrugated pipe.

The first experimental study is presented of a corrugated wall device that uses wakefields to remove a linear energy correlation in a relativistic electron beam (a "dechirper"). Time-resolved measurements of both longitudinal and transverse wakefields of the device are presented and compared with simulations. This study demonstrates the feasibility to employ a dechirper for precise control of the beam phase space in the next generation of free-electron-lasers.

Infectious complications following allogeneic stem cell transplantation: reduced-intensity vs. myeloablative conditioning regimens.

BACKGROUND: In allogeneic stem cell transplantation (allo-SCT), reduced-intensity conditioning (RIC) is known for producing less regimen-related toxicity. However, whether or not RIC reduces the risk for infection and infection-related mortality (IRM) remains controversial. METHODS: We retrospectively analyzed infectious episodes and IRMs after allo-SCTs by time period and by the intensity of the conditioning regimen (RIC [n = 81] vs. myeloablative conditioning, MAC [n = 150]). RESULTS: The cumulative incidence of any kind of infection was lower in the RIC group through the entire period (72% vs. 87%; P = 0.007). The onset of infections was deferred in the RIC group as compared with the MAC group (P = 0.012). Bacteremia occurred less frequently in the RIC group through the entire period (5% vs. 14%; P = 0.044). However, the incidences of cytomegalovirus reactivation and disease, herpes zoster, virus-associated hemorrhagic cystitis, and invasive fungal infection were not different between the two groups. Furthermore, there was no difference in relapse-free survival and IRM between the two conditioning regimens. CONCLUSION: Careful monitoring and appropriate preventive/therapeutic strategies for infectious complications, comparable to those for allo-SCT recipients with MAC, should also be applied to those with RIC, especially after engraftment.

Immunoglobulin D multiple myeloma: response to therapy, survival, and prognostic factors in 75 patients.

BACKGROUND: To analyze the clinical features, outcomes including efficacy of treatment, and prognostic factors of patients with immunoglobulin D multiple myeloma (IgD MM). DESIGN AND METHODS: Seventy-five patients diagnosed with IgD MM were selected from the Korean Myeloma Registry database (www.myeloma.or.kr). RESULTS: Median age was 57 years and the main presenting features were bone pain (77%). Renal function impairment and hypercalcemia were present in 40 (53%) and 20 (27%) patients. Sixty-seven patients (89%) had lambda light chains. Forty-eight patients (64%) were of stage III by International Staging System. Twenty-six patients (53%) had chromosomal abnormalities mostly by conventional cytogenetics. Thirty-nine patients (54%) were treated with vincristine, adriamycin, and dexamethasone chemotherapy; the overall response rate (ORR) of 56%. Sixteen patients (22%) received first-line chemotherapy including new drugs (bortezomib or thalidomide), with an ORR of 81%. At a median follow-up time of 28.6 months, median overall survival (OS) was 18.5 months. Age, extramedullary plasmacytoma, del(13) or hypoploidy, serum ß(2) microglobulin level, and platelet count were significant prognostic factors for OS. CONCLUSIONS: IgD MM is an aggressive disease that is usually detected at an advanced stage. Despite a positive initial response, survival after relapse was dismal. Intensive treatment strategies before and following stem cell transplantation may improve outcomes in younger patients.

Clinical impact of thrombotic microangiopathy on the outcome of patients with acute graft-versus-host disease after allogeneic hematopoietic stem cell transplantation.

The impact of thrombotic microangiopathy (TMA) on outcome was studied in 148 patients with acute graft-versus-host disease (GVHD) (> or =grade II). The Blood and Marrow Transplant Clinical Trials Network's definition for TMA was used to diagnose definite TMA. Probable TMA was diagnosed when none of the features of nephropathy and neurologic abnormalities associated with definite TMA were present. Overall, TMA developed in 43 (29%) patients; 16 definite and 27 probable. The occurrence of TMA, the maximum grade of acute GVHD and initial treatment failure were associated with shorter overall and GVHD-specific survival. The development of probable as well as definite TMA affected the survival of patients with acute GVHD adversely. These results show the clinical impact of TMA on patients with acute GVHD, and suggest that the proposed definitions and grading of TMA may need to be modified.

IL-10-transduced bone marrow mesenchymal stem cells can attenuate the severity of acute graft-versus-host disease after experimental allogeneic stem cell transplantation.

Recent data suggest that adult mesenchymal stem cells (MSCs) might enhance allogeneic hematopoietic engraftment and prevent graft-versus-host disease (GVHD) owing to their immunosuppressive nature. Using a murine model of acute GVHD, this study examined whether or not the immunosuppressive properties of MSCs could reduce the severity of experimental GVHD. The early injection of MSCs after transplant did not attenuate the severity of acute GVHD. Therefore, this study investigated whether or not the use of IL-10-transduced MSCs (IL-10 MSCs) could reduce the severity of acute GVHD. Lethally irradiated recipients were transplanted and injected with IL-10 MSCs, the MSC-expressing vector alone (vector MSCs), or the diluent (controls), respectively, on day +1. Compared with the vector MSCs or controls, there was a significantly lower mortality in the recipients of the IL-10 MSCs at day 50 after the transplant (percent survival, 0 or 10 vs 70%, P=0.0004 or 0.0064, respectively). The decrease in mortality was confirmed by the semi-quantitative GVHD score (P<0.05), and was associated with decreased serum levels of the pro-inflammatory cytokines, IFN-gamma, on day +7 (P=0.015). Therefore, beneficial effects on GVHD were observed when MSCs were engineered to express the anti-inflammatory cytokine, IL-10.

Anti-leukaemic role of acute GvHD after unrelated haematopoietic stem cell transplantation in intermediate- to high-risk acute myelogenous leukaemia.

Little is known about the role of acute GvHD (aGvHD) based on the concept of graft-versus-leukaemia effect (GVLE) after unrelated donor haematopoietic stem cell transplantation (uHSCT). We evaluated 67 uHSCTs performed with multinational unrelated donors for patients with AML. The median follow-up duration was 18 months (range 7-61). The majority of patients had intermediate- or high-risk cytogenetic findings. The conditioning regimen for most patients consisted of cyclophosphamide plus total body irradiation (n=56) with our standard GvHD prophylaxis containing tacrolimus plus a short course of methotrexate. The incidence of aGvHD and chronic GvHD was 50 and 52%, respectively. Eight patients (12%) have relapsed to date. The estimated overall disease-free survival (DFS) rate at 5 years was 67%. Notably fewer relapses were seen when aGvHD developed (P=0.008). Specifically, high-risk AML patients had a much lower relapse rate when they developed aGvHD (P=0.01), compared with the intermediate-risk group. Therefore, the development of aGvHD after uHSCT in AML patients is closely related to a lower relapse rate, probably in association with GVLE.

Dynamic prognostic value of the revised international prognostic scoring system following pretransplant hypomethylating treatment in myelodysplastic syndrome.

This study aimed to analyze the use of the revised International Prognostic Scoring System (IPSS-R) assessed after hypomethylating treatment (HMT) for patients with myelodysplastic syndrome (MDS) undergoing an allogeneic stem cell transplantation (SCT). Among 115 patients who received pre-SCT HMT, comparison analysis of the prognostic values between the IPSS-R at the time of HMT (IPSS-R@HMT) and at the time of SCT after HMT (IPSS-R@SCT) showed a significantly higher predictive power for overall survival (OS) of the latter. Alteration in IPSS-R risk occurred in 60%, while the patients with 'down-staged' IPSS-R@SCT showed better OS compared with those with 'unchanged' or 'up-staged' risk. On multivariate analysis in all 201 patients, IPSS-R@SCT, monosomal karyotype, treatment failure to pre-SCT treatment, and high hematopoietic cell transplantation-comorbidity index were independently associated with OS. Constructed using these factors, the MDS Transplantation Prognostic Scoring System (MTPSS) identified four risk groups with 4-year OS of 76.4% in low, 61.4% in intermediate-1 and 21.9% in intermediate-2 risk groups, whereas all in the high risk group died within 2 years after SCT (P<0.001). Our study emphasizes the need for further studies aiming to evaluate a transplantation prognostic model such as the MTPSS to make appropriate decisions for transplantation in MDS.

Patterns of C-reactive protein release following allogeneic stem cell transplantation are correlated with leukemic relapse.

The C-reactive protein (CRP) is an acute-phase protein produced by hepatocytes, and is a reliable marker of systemic inflammation, which is relevant to the release of the proinflammatory cytokines. The value of monitoring the CRP levels after stem cell transplantation (SCT) can identify patients at risk of treatment-related complications and mortality. Inflammatory cytokines facilitate donor T-cell activation via antigen presenting cells immediately after SCT. This study examined the relationship between the post-SCT CRP levels and a leukemic relapse. Fifty-four consecutively transplanted patients who relapsed after the allogeneic SCT were compared with nonrelapsing patients. The serum CRP levels were measured on day 0 and every 7 days thereafter until 4 weeks after the SCT. The mean CRP levels throughout the early post-SCT episode were significantly lower in the relapsing patients than in those who did not experience relapse (mean+/-s.e.: 26.8 +/- 6.3 vs 65.3 +/- 9.4 for first week, P = 0.001; 23.9 +/- 3.8 vs 44.6 +/- 6.6 for second week, P = 0.008). Univariate analysis showed that the CRP level on the first and second week, and graft-versus-host disease were significantly associated with a relapse. Multivariate analysis showed that the CRP level on the first week was the strongest independent variable predicting the risk of a relapse after SCT (P = 0.04). These results indicate that the serum CRP levels early after allogeneic SCT might display the graft-versus-leukemia (GvL) effect. CRP is a surrogate of the proinflammatory cytokine release that was not measured in this study. The GvL effect appears to be efficiently strengthened by the high CRP levels that may be reflecting T-cell activation.

Vascular endothelial growth factor (VEGF) is associated with reduced severity of acute graft-versus-host disease and nonrelapse mortality after allogeneic stem cell transplantation.

This study investigated whether or not there is a correlation between the changes in the serum levels of vascular endothelial growth factor (VEGF) and the outcome of allogeneic stem cell transplantation (allo-SCT). Eighty-five patients undergoing allo-SCT were prospectively studied. The serum VEGF levels were measured on days 0, +7 and +14 after transplantation. The VEGF levels decreased significantly on day +7 and recovered on day +14. The highest levels from day +7 through day +14 were categorized by cluster analysis, which were then correlated with the nonrelapse mortality (NRM). There was a significant correlation between a low VEGF level and the occurrence of severe acute graft-versus-host disease (GVHD) including grade III-IV (P=0.029). The 1-year probability of NRM in patients with a low VEGF level was 22.5% compared with 3.5% for those with a high VEGF level (P=0.024). Multivariate analysis revealed clinically defined infections (P=0.011), advanced disease (P=0.014) and a low VEGF cluster (P=0.05) to be significantly associated with the occurrence of NRM in the cohort. In conclusion, low VEGF levels after allo-SCT are associated with NRM with an exacerbated severity of acute GVHD. VEGF monitoring after a transplant might identify those patients at risk of severe transplant-related mortality.

MyD88 in donor bone marrow cells is critical for protection from acute intestinal graft-vs.-host disease.

To understand the role of myeloid differentiation factor 88 (MyD88) expressed by donor bone marrow (BM) in the pathophysiology of graft-vs.-host disease (GVHD), we investigated the effects of transplantation of MyD88-deficient T cell-depleted BM (MyD88KO TCD-BM) on the severity of GVHD. Transplantation with MyD88KO TCD-BM aggravated GVHD; serious gut damage was evident, with high infiltration of T cells into the intestines of recipients and markedly reduced expansion of CD11b(+)Gr-1(+) myeloid-derived suppressor cells (MDSCs). MDSCs from MyD88KO mice were defective in inducing donor T-cell apoptosis and inhibiting T-cell proliferation. Supplementation of transplanted mice with MDSCs from wild-type mice, but not MyD88KO mice, attenuated GVHD severity with reduced intestinal T-cell infiltration in MyD88KO TCD-BM recipients. Pretreatment of BM donors with lipopolysaccharide to increase MDSC levels and MyD88 transcription in the TCD-BM transplant alleviated GVHD severity and intestinal T-cell infiltration. The T cell/MDSC ratios were correlated with intestinal GVHD severity in both animal models and human patients. This study indicates that MyD88-dependent MDSC expansion from donor BM is critical for protection against fatal intestinal GVHD.

Impact of pretransplant red cell transfusion on outcome after allogeneic stem cell transplantation in adult patients with severe aplastic anemia.

The aim of this study was to evaluate the impact of pretransplant transfusion of packed red cells (PRCs) on outcome after allogeneic stem cell transplantation (SCT) in severe aplastic anemia (SAA). A total of 221 adult SAA patients receiving allogeneic SCT were analyzed. The patients were divided into two groups according to the amount of pretransplant transfusion before SCT: the low transfusion group (⩽32 PRC units, n=164) and the high transfusion group (>32 PRC units, n=57). The incidence of engraftment failure was not different between the two groups. The incidence of acute GvHD (grades II-IV) was higher in the high transfusion group than in the low transfusion group (P=0.04), and the incidences of chronic extensive GVHD were not significantly different (P=0.136). The high transfusion group had higher 5-year transplant-related mortality (TRM) (24.8% vs 6.8%, P<0.001) and lower overall survival (OS) (72.3% vs 91.9%, P<0.001) than those in the low transfusion group. Multivariate analysis revealed that the high transfusion group and unrelated donor type were independent prognostic factors affecting OS. These results indicate that a history of higher pretransplant transfusion of PRCs was associated with increased TRM and decreased OS, suggesting that iron overload had a negative impact on outcome after SCT in SAA.

Comparable outcomes between younger (⩽40 years) and older (>40 years) adult patients with severe aplastic anemia after HLA-matched sibling stem cell transplantation using fludarabine-based conditioning.

Allogeneic stem cell transplantation from HLA-matched siblings (MSD-SCT) for elderly patients with severe aplastic anemia (SAA) is not a widely accepted first-line treatment. Recently, fludarabine, lower-dose cyclophosphamide and antithymocyte globulin conditioning (Flu/lower-dose Cy/ATG) with lower toxicities has been investigated. To determine whether this regimen can overcome the negative effects of age, we analyzed 117 adult patients with SAA who received MSD-SCT using Flu/lower-dose Cy/ATG, and compared outcomes between 63 younger age group (YAG; ⩽40 years) and 54 older age group (OAG; >40 years) patients. No primary graft failure was observed. Neutrophil engraftment was significantly faster in the YAG compared with the OAG (12 vs 13 days; P=0.04). The incidences of acute grade II-IV (9.5% vs 9.3% at day 100; P=0.42) and chronic GVHD (8.1% vs 9.5% at 5 years; P=0.80), secondary graft failure (20.8% vs 7.9% at 5 years; P=0.11) and transplant-related mortality (5.4% and 11.1% at 5 years; P=0.91) were not significantly different between the YAG and OAG. In addition, failure-free (73.7% vs 81.0% at 5 years; P=0.73) and overall survival rates (93.7% vs 88.9% at 5 years; P=0.20) were comparable. Our results suggest that MSD-SCT using Flu/lower-dose Cy/ATG may be a feasible first-line treatment even in older patients with SAA.

Preemptive treatment of minimal residual disease post transplant in CML using real-time quantitative RT-PCR: a prospective, randomized trial.

Immunotherapy in the form of donor lymphocyte infusions in early-phase relapse might be advantageous as it induces a higher response, but this may be offset by increased toxicity, especially during the early period after transplantation. Among 45 consecutive patients receiving an allograft for CML, 13 patients were diagnosed to have molecular relapse (MRel), as defined by real-time quantitative reverse transcriptase-polymerase chain reaction, and another four patients were diagnosed to have cytogenetic relapse (CRel) within 6 months. Patients with MRel were randomly assigned to either a 'no therapy' group (group A, n=6), in which immunotherapy was reserved until CRel, or an 'immunotherapy' group (group B, n=7). In group A, all MRel progressed to CRel, and molecular remission (MR) was achieved in four (67%) after immunotherapy. The remaining two patients died of extensive GVHD and fungal pneumonia. In group B, only two MRel progressed to CRel and the remaining five (71%) achieved MR. Two patients died in the absence or loss of response. In patients relapsing directly into CRel (n=4), immunotherapy induced MR in two patients (50%). Earlier intervention played a role in preventing disease progression but this effect was not translated into better survival, which could have been overcome by imatinib mesylate, which induced MR and cytogenetic remission in nonresponders without toxicity.

Effect of induced GVHD in leukemia patients relapsing after allogeneic bone marrow transplantation: single-center experience of 33 adult patients.

In a retrospective single center study, we examined the outcome of induced GVHD in leukemia patients relapsing after allogeneic BMT. Thirty-three adult patients with leukemia (15 AML, 3 ALL, and 15 CML) persisting or relapsing 1-36 months (median, 6) after allogeneic BMT underwent various immune manipulations and consequently developed acute and/or chronic GVHD at our center. Immunotherapies to elicit GVHD comprised chemotherapy followed by PBSC (n = 18), non-myeloablative transplant (n = 2), PBL followed by IFN-alpha (n = 5), PBL alone (n = 3), abrupt cessation of CsA (n = 3), and CsA withdrawal combined with IFN-alpha (n = 2). Twenty-four (72.7%) patients obtained a remission including complete hematological or cytogenetic remission, respectively, for acute leukemias or CML. Overall survival of patients, estimated at 3 years using the Kaplan-Meier method, was 33.9% (95% CI, 20-52%). Twelve patients including two patients with ALL remain in complete hematological (n = 5) or cytogenetic remission (n = 7) 3-93 months (median 12) after achieving remission. Twelve (63.2%) of 19 dead patients died due to treatment-related toxicities; five patients from acute GVHD, three from GVHD followed by infections and four from infections. By multivariate Cox analysis, only chronic GVHD resulted in a higher probability of disease-free survival (P = 0.026). Eight patients who had both acute GVHD < or = grade I and chronic GVHD are all alive without leukemia. We conclude that acute GVHD is associated with considerable toxicity while chronic GVHD plays a role in retaining remission in leukemia relapsing after allogeneic BMT.

The kinetics of circulating cytokines including IL-6, TNF-alpha, IL-8 and IL-10 following allogeneic hematopoietic stem cell transplantation.

Pro-inflammatory (IL-6, TNFalpha and IL-8) and anti-inflammatory (IL-10) cytokines were determined in weekly samples from 52 patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). IL-6 increased immediately after transplant peaking at week +3, but IL-8 concentrations were elevated only during week +1. After a slight decrease in week +1, TNF-alpha significantly increased from week +2 and peaked at week +3, whereas, IL-10 values started to rise in week +2 and peaked during week +4. IL-6 and TNF-alpha were positively correlated from week +2 to week +4, and IL-6 levels at week +1 were related with fever and severe stomatitis. Serum levels of IL-6 at week +1 and IL-10 at week +4 were significantly higher in patients with early transplant-related complications, such as fever, severe stomatitis or acute GVHD > or = overall grade II than in those without the complications. We conclude that a high serum IL-6 level at week +1 may be an early predictor of transplant-related complications and that it seems to trigger pro- and anti-inflammatory cytokine release. Kinetic patterns of IL-6 and IL-10 were more exaggerated in those with complications after HSCT.

Changes in autoimmune thyroid disease following allogeneic bone marrow transplantation.

Autoimmune diseases can be transmitted and eliminated by bone marrow transplantation (BMT). There have been several cases of autoimmune thyroid disease (AITD) occurring after BMT, but AITD remission has been rarely reported. We present four cases in which the remission or transfer of AITD occurred after an allogeneic BMT. Two patients with severe aplastic anemia (SAA) showed evidence of remission of Hashimoto's thyroiditis which they had before allogeneic BMT. One patient with SAA, which developed during treatment with propylthiouracil for Graves' disease, underwent allogeneic BMT and showed evidence of Graves' disease remission following BMT. In one patient, new AITD occurred after an allogeneic BMT from an HLA-matched sibling who already had AITD. These cases support the evidence that the immune system is newly reconstituted after BMT, and severe autoimmune disease can be an indication for BMT. To fully understand the real changes in autoimmune status after BMT, long-term prospective studies are necessary.

Human neural stem cells: electrophysiological properties of voltage-gated ion channels.

We have characterized the profile of membrane currents in an immortalized human neural stem cell line, HB1.F3 cells, using whole-cell patch clamp technique. Human neural stem cell line generated from primary cell cultures of embryonic human telencephalon using a replication-incompetent retroviral vector containing v-myc expresses nestin, a cell type-specific marker for neural stem cells. The human neural stem cells expressed both outward and inward K(+) currents with no evidence for Na(+) currents. The density of the outward, delayed rectifying type K(+) current was 1.8 +/- 0.015 nA/pF, and that of the inwardly rectifying K(+) current was 0.37 +/- 0.012 nA/pF (at 30 mM of [K(+)](o)). In order to induce neuronal differentiation of the neural stem cells, a full-length coding region of NeuroD, a neurogenic transcription factor, was transfected into HB1.F3 cells. Introduction of NeuroD induced expression of Na(+) currents with the current density of 0.042 +/- 0.011 nA/pF. The presence of two types of K(+) currents and expression of Na(+) currents induced by NeuroD appear to reflect the characteristic physiological features of human neural stem cells.

Hepatosplenic tuberculosis mimicking disseminated candidiasis in patients with acute leukemia.

Two cases of hepatosplenic tuberculosis in patients with acute leukemia during or after chemotherapy following prolonged neutropenia are presented. Tuberculosis should be considered as one cause of hepatosplenic abscesses during prolonged neutropenia, especially in countries where the disease is endemic.

Substance P inhibits carbamylcholine-stimulated 22Na+ efflux from acetylcholine receptor-enriched Torpedo electroplaque membrane vesicles.

The effect of substance P on nicotinic acetylcholine receptor function was examined in Torpedo electroplaque membranes. The peptide inhibited carbamylcholine-stimulated 22Na+ efflux in a concentration-dependent manner. By irreversibly blocking spare receptors with alpha-bungarotoxin, the IC50 for substance P was shown to be less than 3 microM. Inhibition by substance P was slow relative to receptor activation by carbamylcholine, consistent with an enhancement of desensitization or a slow allosteric block.

Topography of the outer mandibular symphyseal region with reference to the autogenous bone graft.

The mandibular symphysis is preferred as a donor site for the relatively small grafts needed for the autogeneous bone graft procedure. This study was undertaken to determine the morphology and composition of the cortical and trabecular bone in the mandibular symphyseal region using 35 mandible specimens from Koreans. The topographical patterns through the thickness of the cortical plate and the width of the trabecular bone were observed. In this study, the labial cortical plate of the mandible became thicker from the superior to the inferior aspects (P < 0.05). However, the trabecular bone width exhibited a different distribution pattern compared to the thickness of the labial cortical plate. This observation concerning the cortical and trabecular bones assists in determination of the depth of osteotomy. The results provide useful information on the mandibular symphysis graft prior to dental implant placement. These results will enable the volume of the cortical plate in the mandibular symphyseal region and its proper size, depth, and location to be predicted when removing a graft block.