bluuebunny/crossref_metadata_2025_split huggingface dataset:
GATA-1 Directly Induces Physical Proximity between the LCR and β Globin Promoter in Erythroid Cells.
Authors: Vakoc Christopher , Dekker Job , Blobel Gerd A. 
Published: October 2019

Abstract
The regulation of higher-order chromatin folding is a poorly understood aspect of nuclear biology. The beta globin locus is one of the most thoroughly studied mammalian loci with regard to its chromatin organization and sub-nuclear localization. The LCR (locus control region) is a powerful enhancer that acts at great distances to regulate the expression of all beta-like globin genes. Recent evidence suggests that the LCR is in physical proximity with the active but not inactive globin gene promoters, thereby looping out up to tens of kilobases of intervening sequence. The LCR-promoter interaction is dynamically regulated throughout development and cellular differentiation. However, the transcription factors that mediate long range “loops” are unknown. Here we examined the essential erythroid transcription factor GATA-1 for its role in LCR-promoter communication using the 3C (Chromosome Conformation Capture) technique. For our studies we used a genetic complementation assay in which erythroid maturation and globin gene expression depend on the activity of a conditional, drug-activated form of GATA-1. The results suggest that GATA-1 induces proximity of the LCR with the active beta-globin promoter. Kinetic studies revealed that the LCR-promoter interaction occurs rapidly and coincides with or even precedes the onset of globin gene transcription. Moreover, “loop” formation correlates with GATA-1 occupancy as determined by ChIP assay, and occurs in the presence of cyclohexamide, indicating that the effects of GATA-1 are direct. Together, these data suggest GATA-1 is a required component for the formation of a tissue-specific chromatin loop. Additional experiments with mutant versions of GATA-1 that address which known GATA-1 cofactors are required for this novel function of GATA-1 will be discussed.
Combined Immuno-Chemotherapy (R-CHOP) Results in Significantly Superior Response Rates and Time to Treatment Failure in First Line Treatment of Patients with Lymphomplasmocytoid/ic Immunocytoma (LP-IC) - Results of a Prospective Randomized Trial of the German Low Grade Lymphoma Study Group (GLSG).
Authors: Buske Christian , Dreyling Martin H. , Eimermacher Hartmut , Boeck Hans-Peter , Pfreundschuh Michael , Metzner Bernd , Fuchs Roland , Woermann Bernhard , Truemper Lorenz H. , Hess Georg , Wandt Hannes , Ludwig Wolf-Dieter , Kreuser Ernst-Dietrich , Schimke Joerg , Weh H.-J. , Schmitz Stephan , Schmiegel W. , Unterhalt Michael , Hiddemann Wolfgang 
Published: October 2019

Abstract
Lymphomplasmocytoid/ic immunocytoma (LP-IC), including Waldenstrom’s macro-globulinemia and lymphoplasmacytoid lymphoma according to the Kiel classification (the latter one subsummed as a variant of B-CLL in the WHO classification), is an indolent lymphoma, which is incurable by conventional chemotherapy in the advanced stage of disease. The anti-CD20 antibody Rituximab has shown remarkable activity in indolent lymphomas, in particular when combined with chemotherapy. Based on these results the GLSG investigated the efficacy of a combined immuno-chemotherapy (R-CHOP: Rituximab 375 mg/m2 d0-1; cyclophosphamide 750 mg/m2 d1; doxorubicine 50 mg/m2 d1; vincristine 1.4 mg/m2 d1; prednisone 100 mg/m2 d1-5) versus CHOP alone as first line treatment of LP-IC in a multicenter prospective randomized phase III trial. Of 72 patients 71 % were classified as lymphoplasmacytic lymphoma, 29 % as lymphoplasmocytoid subtype by central pathology review. The median age was 61.5 years (60 years for R-CHOP and 62 years in the CHOP arm); 24% of the patients had an IPI score >2. The overall response (OR) rate was significantly improved by combining Rituximab with CHOP compared to CHOP alone with an OR of 94% (11% CR, 83% PR) for R-CHOP and an OR of 69% (3% CR, 67% PR) for CHOP (p=0.012). Furthermore, patients treated with R-CHOP showed a significantly prolonged time to treatment failure (TTF) with an estimated median TTF of 22 month in the CHOP arm, whereas the median was not reached in the immunochemotherapy arm after a maximum follow up of nearly 4 years (p=0.0057). There was no major difference of the toxicity in both treatment groups. In summary, these data indicate a beneficial effect of combined immunochemotherapy (R-CHOP) as compared to CHOP alone with regards to initial cytoreduction as well as TTF in patients with LP-IC in a prospective randomized trial, establishing R-CHOP as an highly attractive regimen for first line treatment of this distinct lymphoma subtype.
The Impact of Anemia on Mortality, Cognition and Function in a Racially Diverse Community-Dwelling Elderly Population.
Authors: Denny Susan , Kuchibhatla Maragatha , Cohen Harvey Jay 
Published: October 2019

Abstract
The WHO definition of anemia, Hgb<12g/dL (W) and <13g/dL (M) is largely based on studies in younger populations. As our population is aging it is important to explore the impact of varying Hgb levels on mortality and function in representative populations of older persons. The Duke Established Populations for Epidemiologic Studies for the Elderly (EPESE) is a random household sample, over sampled for African Americans (AA), initiated in 1986. In 1992 we obtained Hgb levels for 1744 subjects age >71 and evaluated functional and cognitive status at baseline and 4 years later, and mortality for 8 years. Using WHO criteria, the prevalence of anemia was 24%. It was age related; 17% (65–74), 25% (75–79), 32% (>80) p<.0001, but not gender related. There was a strong racial difference, 33.6% AA, 13.8% Caucasians (p=<.0001) with an odds ratio, adjusted for age, education, renal insufficiency and comorbidity of 3.0 (95%CI 2.3 – 3.9) Baseline functional status was worse in anemic subjects (p<.0001) but cognition was not (p=.06). The risk ratio for 8 year mortality was 1.7 (95% CI 1.5, 2.0) for anemic subjects (p=.0001). This did not differ by gender nor, despite the increased prevalence, by race (RR AA: caucasian = 0.85; 95% CI 0.6–1.2). Assessing survival by Hgb level, a nonlinear relationship was seen, with highest % survival between 13–14 g/dL for women (p<.0001) and 14–15g/dL for men (p=.09). Using the WHO standard as reference, controlling for baseline characteristics, women with Hgb 10–11 g/dL had higher mortality (RR 2.1, 95% CI. 1.5 –3.1) but with 11–12 g/dL did not. Similarly men with Hgb 10–11 g/dL had increased mortality (RR2.0, 95% CI 1.1, 3.7). In women there was a progressively greater decline in function at 4 years with each decrement of Hgb level from 16 to 10g/dL, but not in men. Both women and men with mild anemia (11–12 g/dL and 10–11g/dL respectively) had greater decreases in cognition than those at higher levels (p=.01). Thus in an elderly community based population, anemia is significantly more common in AA independent of disease status, and is independently associated with increased mortality over eight years for both races and genders, and with declines in function and cognition most prominently in women. Further investigation of the etiology of these relationships is warranted.
Generation of Cytotoxic T Cell Responses Directed to HLA Class I Restricted Epitopes from the Aspergillus f16 Allergen.
Authors: Ramadan Gamal , Davies Barbara , Kurup Viswanath P. , Keever-Taylor Carolyn A. 
Published: October 2019

Abstract
Invasive pulmonary aspergillosis is a primary cause of morbidity and mortality in immunocompromised patients such as hematopoietic progenitor cell transplant patients. Studies both in patients with allergic bronchopulmonary aspergillosis and murine models demonstrated the importance of a CD4+ Th1 T cell response in conferring protection from infection or preventing disease progression. The role of CD8+ T cell response to A. fumigatus is less clear. Our efforts to develop effective immunotherapeutic approaches against A. fumigatus included preparation of 104 overlapping pentadecapeptides spanning the 427 aa coding region of the aspergillus allergen, Asp f16 previously shown to induce T cell responses. Each 15 aa peptide overlaps the preceding peptide by 11 aa. Monocytes from healthy donors were treated with GM-CSF and IL-4 for 2-3 days to generate immature dendritic cells (fast DC), pulsed with a pool containing 1 μg of each pentadecapeptide, then matured with inflammatory cytokines (IL-1β, IL-6, PGE2 and TNF-alpha) for 2 days. Mature, pulsed fast DC were used to prime proliferative and CTL responses (weekly primings). T cells from 5/5 donors proliferated to the peptide pool. CTL lines were obtained from each of the first two donors that were primed. After 4 weeks the line from donor #2 was strongly cytotoxic to autologous peptide pool-pulsed and aspergillus culture extract-pulsed DC and peptide pool pulsed HLA Class I matched BLCL. Supernatant from this line killed fresh aspergillus conidia. Six of 21 smaller pools of 4-11 peptides showed reactivity. Specificity could be narrowed by screening peptides shared by the pools to 3 candidate peptides. Pool-pulsed BLCL matched for only 1 or 2 HLA alleles were used to demonstrate CTL restriction by HLA-B-3501. A database search of peptides likely to be restricted to B3501 identified the likely sequences as YFKYTAAAL, LPLCSAQTW, and GTRFPQTPM. Each induced similar reactivity when pulsed onto B-3501+ targets. CD8+ T cells steadily increased from 5.2% at week 3 to 19.0% after the 7th priming. CTL activity and IFNγ production were exclusively mediated by CD8+ T cells and CD107a was expressed by 42% of the CD8+ T cells in response to pool-pulsed BLCL indicating degranulation. CTL cross-reacted with pool pulsed B3503+ BLCL but not B3502+, or B3508+ BLCL. B3503+ BLCL presented YFKYTAAAL and to a lesser extent GTRFPQTPM but not peptide LPLCSAQTW. Our data show that DC pulsed with a pentadecapeptide pool from Asp f16 are capable of inducing a CD8+, HLA-Class I restricted Aspergillus-specific T cell response directed to multiple peptides contained within the pool. Further characterization of this system is in progress to identify additional immunogenic peptides from Asp f16 that might be useful in clinical immunotherapy protocols to prime protective immune responses to prevent or treat aspergillus infection.
Generation of Th1 T Cell Responses Directed to a HLA Class II Restricted Epitope from the Aspergillus f16 Allergen.
Authors: Ramadan Gamal , Davies Barbara , Kurup Viswanath P. , Keever-Taylor Carolyn A. 
Published: October 2019

Abstract
Invasive pulmonary aspergillosis is a primary cause of morbidity and mortality in immunocompromised patients, including hematopoietic progenitor cell transplant patients. Studies in patients with allergic bronchopulmonary aspergillosis as well as murine models have demonstrated the importance of a CD4+ Th1 T cell response in conferring protection from infection or preventing disease progression. A. fumigatus allergens have been identified based on reactivity to IgG and IgE antibodies in serum from patients with allergic bronchopulmonary aspergillosis. One allergen, Asp f16 was shown to induce a protective Th1 T cell response to infection with aspergillus conidia in murine studies. We prepared a series of 104 overlapping pentadecapeptides spanning the entire 427 aa coding region of Asp f16. Each 15 aa peptide overlaps the preceding peptide by 11 aa. Autologous monocytes from healthy donors were treated with GM-CSF and IL-4 for 2–3 days to generate immature dendritic cells (fast DC), pulsed with a pool containing 1 μg of each pentadecapeptide, then matured with inflammatory cytokines (IL-1β, IL-6, PGE2 and TNF-α) for 2 days. Mature, pulsed fast DC were used to prime proliferative and CTL responses (weekly primings). T cells from 5 of 5 donors proliferated to the peptide pool. CTL lines were obtained from each of the first two donors that were primed. As early as 3 weeks the T cell line from donor #1 had a high frequency of IFNγ-producing CD4+ T cells (24.5±5.4%) in response to the peptide pool, was cytotoxic to autologous peptide pool-pulsed and aspergillus culture extract pulsed DC, and peptide pool pulsed autologous BLCL. Supernatant from this culture killed fresh aspergillus conidia. Screening of 21 smaller pools containing 4–11 peptides showed reactivity to three smaller pools and could be narrowed by screening individual peptides shared by the pools to a single candidate sequence of TWSIDGAVVRT that elicited IFNγ production and lytic activity equal to the entire pool. Peptide pulsed BLCL matched with the donor for only 1 or 2 HLA alleles were used to demonstrate that CTL activity and IFNγ production was restricted by HLA-DRB1- 0301. 23% of the CD4+ cells in the culture expressed CD107a in response to peptide pool indicating degranulation. PBMC from DRB1-0301+ individuals proliferated strongly in response to peptide TWSIDGAVVRT. Our data show that DC pulsed with a pentadecapeptide pool from Asp f16 are capable of inducing a CD4+, HLA-DR-restricted aspergillus-specific Th1 type T cell response directed to a single peptide contained within the pool. Further characterization of this system is in progress to identify other immunogenic peptides from Asp f16 that might be useful in clinical immunotherapy protocols to prime protective immune responses to prevent or treat aspergillus infection.
Acute Chest Syndrome Is Strongly Associated Parvo Virus B19 Seroconversion in Patients with Hemoglobin SC Disease.
Authors: Coates Thomas D. , Dampier Carlton , Kalinyak Karen , Lail Alice , Mentzer William , Piomelli Sergio , Radel Eva , Space Sharon , Howard Thomas 
Published: October 2019

Abstract
Parvovirus B19 replicates principally in human erythrocyte precursors resulting in temporary cessation of erythropoiesis. In patients with sickle hemoglobinopathies, parvovirus B19 infection has been associated with acute chest syndrome and may lead to transient aplastic crisis. Evidence of prior infection with parvovirus B19 is found in 50 to 60% of adults. Infection appears to be followed by lifelong immunity. The objectives of the Study of Seroprevalence and Incidence of Parvovirus B19Infection in Children with Sickle Hemoglobinopathies are to determine the prevalence of parvovirus B19 antibodies in children less than 16 years old; determine the rate of parvovirus B19 seroconversion; and determine whether parvovirus B19 seroconversion is associated with the occurrence of aplastic crisis or acute chest syndrome. Between April 2000 and June 2002 a total of 1039 children from eight Comprehensive Sickle Cell Centers (CSCC) were enrolled in the study and 898 had at least one follow up visit. Participants ranged in age from <1 month to 16 years at enrollment (mean age 7.2, + 4.5 years), 47% were female, 53% were male. 67% had homozygous Hb SS disease, 24% had Hb SC disease, 6% had Hb SB+ disease, 3% had Hb SB0 disease, and <1% had other S sickle cell disease. The seroprevalence of parvovirus B19 in the cohort was 35%. Prevalence varied significantly by age, ranging from a low of 8% for children 1–2 years of age to 69% for children 13+ years of age (p<0.0001). The greatest increase in seroprevalence occurred between 6 and 7 years of age. Adjusted for age, there were no significant differences in seroprevalence by gender, clinical center, geographic area of residence (northeast, southeast, midwest, and west) sickle hemoglobinopathy, number of siblings, hemoglobin level, reticulocyte %, or among recipients of treatment with transfusion or hydroxyurea. Parvovirus B19 seroconversion was strongly associated with an increased risk of aplastic crisis in both SS (odds ratio of 29, 95% CI (11.3, 74.4)) and SC patients (odds ratio of 110, 95% CI (9.6, 1270.4)), even when controlling for age. Seroconversion was associated with an increased risk of acute chest syndrome in SC patients, (odds ratio of 6.4, 95% CI (1.9, 21.9)) but did not reach statistical significance in SS patients.
These data show a clear causal relation between parvovirus B19 seroconversions and acute chest syndrome in subjects with hemoglobin SC disease and confirm the previously known association aplastic crisis.
The Role of BMP-4 in the Stromal-Maintenance of Haematopoietic Stem Cells.
Authors: Hutton Jonathon F. , Khor Fiona , Rozenkov Vlad , Lewis Ian D. , D’Andrea Richard J. 
Published: October 2019

Abstract
Haematopoietic stem cells (HSCs) expand in number during fetal liver hematopoiesis via a process that is not understood. Establishment of conditions supporting HSC maintenance and expansion ex vivo is critical for wider application of cord blood derived HSC. We have shown that bone morphogenic protein (BMP) 4 secreted by mouse foetal liver cells contributes to expansion of cord blood-derived HSCs during in vitro co-culture. Significant levels of BMP-4 mRNA and secreted protein were produced by the supportive murine foetal liver stromal cell line AFT024. Supplementing 14 day co-cultures of AFT024 and human cord blood CD34+ cells with the BMP-4 antagonist Noggin, or a neutralising BMP-4 antibody decreased the proportion of cells maintaining a CD34+CD38−CD33− primitive phenotype (by 27.6% and 37.2% respectively), decreased CFU-GM expansion (by 20.6% and 22.2% respectively), and caused a large reduction in net expansion of long-term culture-initiating cells (LTC-IC) (by 31.7% and 61.5% respectively). The ability of BMP4 to support the multipotency and self-renewal of hematopoietic stem cells is consistent with a role recently shown on embryonic stem cells and suggests that it may act generally as a stem cell maintenance factor. Elucidating further the role of HSC growth factors such as BMP-4 in ex vivo culture may lead to development of defined systems for the routine clinical expansion of HSC.
Negative Impact of Pre-Transplant Anemia on Long-Term Outcome after Allogeneic Hematopoietic Stem Cell Transplantation.
Authors: Lazongas Chris , Wong Cindy J. , Sutton David M. , Lipton Jeffrey H. , Xenocostas Anargyros , Messner Hans A. 
Published: October 2019

Abstract
Background: Anemia is commonly present in patients with malignancies and is associated with reduced survival times. Recently, we described that low (<110 g/L) pre-transplant hemoglobin levels (PT-Hb) are associated with decreased early survival after allogeneic hematopoietic stem cell transplantation (alloHSCT)(Xenocostas et al. Transfusion2003;43:373–382). We are now presenting data on long-term survival and causes of death in BMT recipients with and without anemia prior to alloHSCT.
Study Design and Methods: A retrospective analysis of 511 patients consecutively transplanted between January 1995 and March 2000 was performed to evaluate survival, cause of death, and PT-Hb. The end date for follow-up was June 2002. The median follow-up time was 993 days. Causes of death were categorized either as relapse, treatment-related mortality (TRM), or other. PT-Hb levels were determined within 2 weeks prior to transplantation, after commencing conditioning chemotherapy. Comparisons between groups were done using chi-squared tests.
Results: The 180-day survival of patients with low PT-Hb levels (<110 g/L) was significantly worse than that of patients with PT-Hb levels ≥110 g/L (57.1% versus 83.1%, p<0.0001). The survival difference remained significant at 5 years (36.2% versus 59.4%, p<0.0001). The difference in 180-day survival was contributed to by an increase in TRM (36.1% versus 14.9%, p<0.0001) as well as a higher relapse rate (4.4% versus 0.3%, p=0.019 by Fisher’s exact test). For patients surviving more than 180 days, there was no difference in TRM (16.7% versus 16.7%, p=0.987) or relapse rate (12.0% versus 7.3%, p=0.150). No difference in the rate of other causes of death was found between the groups at either the 180-day or 5-year time points.
Conclusions: Pre-transplant anemia is an independent risk factor for increased mortality following alloHSCT. Relapse and treatment-related deaths are both more likely to occur early in the post-transplant course of patients experiencing pre-transplant anemia. Differences in long-term survival are predominantly related to treatment-related deaths rather than relapse.
Comparison of Closure Times and Bleeding Times in the Evaluation of Patients Referred for Mild Bleeding Disorder Evaluations.
Authors: Zeigler Zella Rose , Hassett Andrea L. Cortese 
Published: October 2019

Abstract
The bleeding time has largely been replaced by closure times using a PFA-100 device for the evaluation of patients with suspected platelet function defects or von Willebrand’s disease. Initial studies showed concordance with both tests being abnormal in well defined thrombocytopathies (thrombasthenia, Bernard-Soulier syndrome, storage pool deficiency, and aspirin-like defects) and in von Willebrand’s disease. However recent studies have suggested that the closure time may be particularly insensitive in the more common platelet secretion disorders. This is a retrospective medical record review study to compare the results of closure times and bleeding times performed the same day in a consecutive series of patients evaluated for mild bleeding disorders. Incusion criteria were all patients referred to the PI at the Hemostasis and Thrombosis outpatient clinic at the Institute for Transfusion Medicine for such an evaluation, who had both closure and bleeding times performed on the same day. Exclusions were patients who did not have these tests performed on the same day. Platelet function testing included platelet aggregation in platelet rich plasma (epinephrine-11 micromolar, ADP 2.5, 5, 10 and 20 micromolar, collagen 2 mg/ml, high and low dose Ristocetin), adenine nucleotides.If these were normal, whole blood aggregation and ATP secretion were also assessed. Von Willebrand parameters (on at least three different dates) and von Willebrand multimers were measured. Thirty-two patients were evaluated and of these, two had normal tests. The remaining thirty patients (8M:20F) had a median age of 51 (range = 18 to 80). Seventeen pts (57%) were referred for abormal surgical bleeding, four (13%) were evaluated for bleeding (CNS in two, menorrhagia in two), one pt for excessive bruising and the remainder because of abnormal tests.Their diagnoses were platelet secretion defects (n=20), storage pool deficiency (n=5), aspirin-like defects (n=4) and von Willebrand’s disease type 1 (n=1). Bleeding times and closure times were both abnormal in only 3/30 pts (10%).CT coll/epi and CT coll/ADP results were abnormal in 5/30 (17%) and in 3/30 (10%) respectively. By contast, bleeding times were abnormal in 19/30 (63%). Only two/30 pts (7%) had isolated prolongation of the closure times. Of note, 9/30 patients (30%) had normal values in all three screening assay parameters. Using ROC analysis, the area under the curve was not significant for closure times with p values for CT:coll/epi of 0.387 and for CT:coll/ADP of 0.362. However, the p value for bleeding times was significant at <0.001. Using a cutoff bleeding time of greater or equal to 7.5 minutes, the sensitivity was 67% and specificity was 100% for this group of patients. We conclude that the closure time is not a good screening assay for patients with the more common thrombocytopathies. Unfortunately bleeding times also remain insensitive for screening for these disorders.