bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anemia of Chronic Renal Failure Is Associated with Much Higher Frequency of Apoptosis in Erythroid Progenitor in a Mouse Model.
Authors: Oyake Tatsuo , Ito Shigeki , Kowata Shugo , Murai Kazunori , Sawai Takashi , Ishida Yoji 
Published: April 2020

Abstract
Insufficient production of erythropoietin (EPO) is one of the important causes of anemia of patients with chronic renal failure (CRF). Recombinant human erythropoietin (rh-EPO) administration results in a dramatic improvement of anemia in these patients. In ASH meeting 2001, we reported that excessive apoptosis in erythroid progenitor was observed in anemia of CRF patients before rh-EPO administration. In this study, we established a mouse model of anemia of CRF to confirm the hypothesis that excessive apoptosis in erythroid progenitor induced anemia. C57B6 male mice was treated with adenine-rich diets (ADRD) for 8 weeks. Serum blood urea nitrogen (BUN), creatinine (Crt) and complete blood count (CBC) were measured every week. The frequency of apoptosis in erythroid progenitor and mature erythroblasts were evaluated by three color flow cytometric analysis. Apoptotic cells were analyzed by AnnexinV. The cell populations of erythroid progenitor were identified as CD34(+)erythropoietin-receptor (EPO-R)(+) cells and mature erythroblasts identified as CD34(-)EPO-R(+) cells. Serum BUN and Crt levels began to elevate from 2 weeks after ADRD administration (BUN; 40.1±4.6, 73.2±14.4, 150.7±11.6, 164.0±8.4, 193.0±23.3mg/dl, Crt; 0.06±0.04, 0.30±0.03, 0.51±0.07, 0.68±0.09, 0.80±0.17mg/dl, n=5: mean±SD at 0, 2, 4, 6 and 8 weeks after ADRD administration, respectively). Hb and Ht began to decrease from 6 and 4 weeks after ADRD administration (Hb; 13.6±0.4, 13.3±0.3, 13.2±0.2, 10.2±0.5, 8.3±0.5 g/dl, Ht; 52.4±1.4, 49.4±1.7, 43.6±0.2, 35.4±1.8, 30.8±1.6%, n=5: mean±SD at 0, 2, 4, 6 and 8 weeks after ADRD administration, respectively). Serum EPO levels were not elevated after ADRD administration, regardless of anemia. Much higher frequency of apoptosis was observed in erythroid progenitor from 4 to 8 weeks after ADRD administration, compared to that at 0 week (CD34(+)EPO-R(+); 18.2±7.4, 41.7±7.3, 56.0±4.8, 76.4±5.3, 70.1±6.9, 73.8±8.7%, n=5, mean±SD at 0, 4, 5, 6, 7 and 8 weeks after ADRD administration, p&lt;0.05, respectively). While, the frequency of apoptosis was not high in mature erythroblasts after ADRD administration (CD34(-)EPO-R(+); 1.58±1.4, 0.21±0.1, 0.58±0.1, 0.77±0.7, 0.49±0.2, 0.25±0.2%, n=5, mean±SD at 0, 4, 5, 6, 7 and 8 weeks after ADRD administration, N.S, respectively). Pathological examination of kidney showed that tubular damage was diffusely observed from 2 to 8 weeks after ADRD administration, and tubular necrosis was suspected as the major cause of renal failure.
Our findings suggested that excessive apoptosis occurred mainly in CD34(+) erythroid progenitor by insufficient production of EPO, which induced anemia in mice with CRF.
The V617F JAK2 Mutation Is Very Uncommon in Idiopathic Erythrocytosis.
Authors: Cassinat Bruno , Parquet Nathalie , Kiladjian Jean-Jacques , Massonnet Gerald , Menot Marie-Laurence , Chomienne Christine 
Published: April 2020

Abstract
The V617F JAK2 mutation is highly frequent in Polycythemia Vera (PV) patients. Indeed, we and others found the mutation in 70 to 90% of PV patients. However one of the most difficult differential diagnoses of PV is the idiopathic erythrocytosis (IE), as this diagnosis is based on negative criteria and exclusion of PV. However the differential diagnosis is of the utmost importance because IE is not considered as a clonal disease and should not transform to PV. Our centre is specialized in the diagnosis of myeloproliferative diseases, thus we have reviewed 22 cases with pure idiopathic erythrocytosis in the aim of defining the impact of V617F JAK2 mutation in this pathology. Median age of the patients was 46 (range: 29 to 67). Patients were diagnosed on the basis of an elevation of the hematocrit and a raised red cell mass without any identifiable cause of secondary erythrocytosis. PV diagnosis has been carefully excluded according to revised Pearson’s criteria. Median excess of red cell mass was +35% (range: +25% to +104%). Median hematocrit was 54% (range: 49% to 56%), median WBC (x109/L) was 6180 (range: 3500 – 8300) and median platelet count (x109/L) was 240 (range: 174 – 358). Serum Epo level was under or within the normal range in all patients except one case in whom an unexplained elevated level (x2 the upper normal limit) was found. Finally no splenomegaly was observed in these 22 patients. Because of the importance of a correct diagnosis distinguishing between PV and IE it was very important to test whether the JAK2 mutation could allow a correct classification. We have analysed DNA isolated from peripheral blood granulocytes. V617F JAK2 mutation was detected using a quantitative PCR and Taqman probes with a sensitivity of 2–4%. All of the 22 patients with IE were tested negative. This result confirms
that IE is a distinct entity from PV, and also confirms the potential for the V617F JAK2 mutation detection to help in the differential diagnosis of erythrocytosis. Indeed, the presence of a JAK2 mutation in the context of erythrocytosis with increased red cell mass is highly specific of PV.
Cardiac Biomarkers Predict for Ability To Tolerate and Complete Therapy with Lenalidomide ± Dexamathosone in AL Amyloidosis.
Authors: Dispenzieri Angela , Lacy Martha , Zeldenrust Steven , Hayman Suzanne R. , Kumar Shaji , Geyer Susan M. , Lust John A. , Allred Jacob B. , Witzig Thomas E. , Rajkumar S. Vincent , Greipp Philip R. , Russell Stephen J. , Kabat Brian , Gertz Morie Abraham 
Published: April 2020

Abstract
Background: Primary systemic amyloidosis (AL) is an incurable plasma cell disorder. Lenalidomide, especially in conjunction with dexamethasone, has been shown to be highly active in patients with multiple myeloma.
Methods: We studied the toxicity and efficacy of lenalidomide in patients with symptomatic AL. Patients received single agent lenalidomide. If progression by 3 months or no evidence of hematologic response after 3 cycles, dexamethasone was added. Originally, twenty-three patients (Cohort 1) were enrolled according to study design. Because of a significant early drop out rate and notable activity of the regimen, the trial was modified to include an additional 15 patients (Cohort 2). Baseline characteristics and adverse events are available for all enrolled patients, but at the time of this writing, response data are available for Cohort 1 patients due to short follow-up of Cohort 2, but will be updated by the time of the meeting.
Results: Median age was 64 years, with 69% male. Twenty-three were previously treated. Organ involvement was cardiac (67%), renal (64%), hepatic (17%), nerve (17%). Thirty-three, twenty-two, and forty-four percent of patients were cardiac biomarker stage 1, 2, and, 3 respectively. Of the 37 patients, one was a cancel, and 6 have not yet made it through 3 months of protocol treatment and event monitoring. The respective median follow-ups for Cohorts 1 and 2 are 17 and 3.4 months. Of the remaining, 30 patients, within the first 3 cycles of therapy fifteen patients discontinued treatment: 7 early deaths and 8 adverse events or other causes. Three additional patients died 0.5 to 2 months after stopping treatment. The best predictor for early withdrawal and/or death was baseline NT-proBNP and cardiac biomarker staging system (cut-offs for serum troponin T &lt;0.035 ng/ml and NT-proBNP &lt;332 pg/ml--Stage I neither above cut-off; Stage III, both above cut-off; and Stage II, one above cut-off).
Figure1 Figure1. Figure 2 Figure 2.
Of the twenty 22 patients assessed for response ten patients responded to treatment for an overall response rate of 45%, including 23% organ responders. Among the patients with organ responses, there were four renal responses, two cardiac responses and two liver responses. All but one of the responders had dexamethasone added to their treatment program. The most common grade 3−4 adverse events at least possibly attributable to lenalidomide were neutropenia (38%), thrombocytopenia (21%), fatigue (15%), and rash (12%).
Conclusions: Lenalidomide and dexamethasone has significant activity in patients with AL with an overall response rate of 45%. Baseline NT−proBNP may be an effective eligibility screening strategy for subsequent trials.
Anemia in Centenarians Is Associated with Elevated Serum 2−Methylcitric Acid but Not Other Measures of Cobalamin Deficiency or Renal Status.
Authors: Stabler Sally P. , Allen Robert H. , Johnson Mary Ann , Hausman Dorothy B. , Davey Adam , Poon Leonard W. 
Published: April 2020

Abstract
Anemia in seniors is associated with increased mortality and frailty. It is important to determine the cause of anemia in order to initiate specific therapies. We studied cobalamin (Cbl) and folate status with other clinical and laboratory parameters associated with anemia in 234 centenarians from north Georgia aged 98–108 years, 197 female, 46 African-American. The Cbl and folate dependant metabolites included methylmalonic acid (MMA), total homocysteine (Hcys) and 2-methylcitric acid (MC). MMA, MC and Hcys are elevated in clinical Cbl deficiency. MC is also elevated with even mild renal insufficiency. Metabolites were assayed by capillary gas chromatography/mass spectrometry. The median hemoglobin (Hgb) and hematocrit (Hct) were 12.0 g/dL and 35.2 %. Severe anemia (Hgb &lt; 8 g/dL) occurred in only 1 white female with serum ferritin of 10 ng/mL. The 10th percentile for hemoglobin was 10.0 g/dL, and in this group, serum MC was increased (p = 0.021), albumin trended lower (p = 0.056) but serum folate, Cbl, Hcys, MMA, and creatinine were not significantly different. Univariate analysis between variables for the whole cohort showed that Hgb was inversely correlated with Hcys (p = 0.028), MC (p = 0.003), creatinine (p = 0.030) and directly with albumin (p = 0.001). In multivariate analysis, albumin was the strongest positive predictor of Hgb and MC was significantly inversely related, whereas creatinine and Hcys were no longer independent determinants. Elevated MMA with low Cbl was common in this cohort but not associated with anemia. Even those above the 90th percentile for MMA (844–8080 nmol/L) actually had higher Hgb as compared to the rest of the cohort, 12.3 vs. 12.0 mg/dL (p = 0.096). Folate status was high in this cohort (50th percentile (12.9 ng/mL) and those taking a multivitamin (33%) had 1.5 fold higher serum folate (p &lt; 0.001), 17 % lower Hcy (p = 0.001) and 24 % lower MMA (p = 0.045) but no difference in Hgb. The only racial difference was that MMA was lower in African-Americans (p &lt;0.001) and the only sex difference was that creatinine was higher in males (p = 0.025). Those with MC above the 90th percentile (&gt; 415 nmol/L) had lower Hgb (p = 0.038), higher creatinine (p = 0.003), Hcy (p = 0.003) and MMA (p = 0.060). Ferritin was less than 50 ng/mL in 10/22 subjects with the lowest 10th percentile Hgb value (&lt; 10.0 g/dL). One subject had apparent folate deficiency and 7/22 had serum creatinine &gt; 1.3 mg/dL. Two subjects with MCV &gt; 100 fl had renal insufficiency. In conclusion, 1. High serum 2-methylcitric acid and low serum albumin predict anemia in centenarians. 2. Serum 2-methylcitric acid may be a sensitive indicator of renal failure- associated anemia. 3. Cbl deficiency was not associated with anemia in this cohort with high folate status.
Hypoxia Inhibits HIV-1 Transcription.
Authors: Nekhai Sergei , Sharroya Charles , Ammosova Tatyana , Nui Xiaomei , Jerebtsova Marina , Gordeuk Victor R. 
Published: April 2020

Abstract
The hypoxic response is an important component of the body’s reaction to impaired tissue oxygenation associated with the anemia and vasoocclusive episodes of sickle cell disease (SCD). It has been reported that HIV infection progresses relatively slowly in patients with SCD (Am J Hematol1998;59:199–207). HIV-1 Tat protein promotes transcription of HIV-1 genes by inducing CDK9/cyclin T1 to phosphorylate the C-terminal domain of RNA polymerase-II. Our previous studies indicate that protein phosphatase-1 (PP1) promotes Tat-induced HIV-1 transcription (J Biol Chem2003;278:32189–941), apparently by interacting with HIV-1 Tat, for disruption of this interaction prevents induction of transcription (J Biol Chem2005;280:36364–71). Recently PP1 activity was shown to be decreased in hypoxia in part through increased association of PP1 with NIPP1 (J Cell Physiol 2006 Jul 6; Epub ahead of print). We hypothesized that decreased PP1 activity during hypoxia would reduce HIV-1 transcription and viral replication, and we have obtained experimental results consistent with this hypothesis.Increased expression of nuclear inhibitor of PP1 (NIPP1) was associated with inhibition of HIV-1 transcription and viral replication.Low oxygen tension (3%–6% O2) was associated with transient inhibition of HIV-1 transcription in transfected 293T and HeLa cells.Low oxygen tension was associated with inhibition of HIV-1 transcription in CEM T cells infected with pseudotyped HIV-1 virus.
We are now planning to examine the possible role of altered PP1 activity in the observed inhibition of HIV-1 transcription during hypoxia. Thus, a clinical insight from patients with SCD has pointed the way to investigating the influence of hypoxia on HIV transcription. An improved understanding of how oxygen status influences viral activation versus inactivation might open new possibilities for treatment of hidden HIV-1 reservoirs that harbor non-replicating HIV-1 virus.
The Role of EHZF in Erythroid Differentiation of K562 Cells.
Authors: Matsubara Etsuko , Sakai Ikuya , Yamanouchi Jun , Azuma Taichi , Narumi Hiroshi , Hato Takaaki , Hasegawa Hitoshi , Yasukawa Masaki 
Published: April 2020

Abstract
Early hematopoietic zinc finger protein (EHZF), the human homolog to mouse Evi3, is a transcription factor with 30 zinc fingers and a highly conserved N-terminal FOG repression motif. The EHZF mRNA expression is abundant in early hematopoietic progenitors and declines during differentiation. In most of the leukemic cells from acute myelogenous leukemia patients, significant levels of EHZF mRNA are detected. These findings suggest that EHZF play an important role in hematopoietic differentiation.
In the present study we investigated whether siRNA-mediated depletion of EHZF affected the erythroid differentiation of K562 cells. Three kind of EHZF siRNA were designed and their expression vectors were constructed. After transient expression of these siRNAs by electroporation, hemoglobinization of K562 cells were analyzed by Benzidine staining. In all of these siRNAs introduced cells, the levels of hemoglobinizations were abundant compared to control cells, which suggested that EHZF might influence the erythroid differentiation of K562 cells. To further analyze the effects of EHZF siRNA in erythroid differentiation, we established K562 clones in which EHZF was depleted by siRNA. EHZF siRNA expression vectors were introduced into K562 cells by electroporation and the expression of EHZF mRNA were examined by RT-PCR in G418 resistant clones. The depressions of EHZF mRNA in the clones were confirmed by Northern blotting. We isolated several EHZF depleted clones in each kind of EHZF siRNA introduced cells. Most of the EHZF depleted clones showed marked hemoglobinization by Benzidine staining compared to control clones, and surface expressions of glycophorin A were also increased in these clones. These results confirmed the relevant role of EHZF in erythroid differentiation of K562 cells. Comparison of mRNA expressions between an EHZF depleted clone and a control clone using DNA array showed increase expressions of hemoglobin alpha, beta, delta mRNA in EHZF depleted clone compared to control clone. Several transcription factors which are involved in erythroid differentiation also showed the difference mRNA levels between two clones.
Studies are underway to elucidate the mechanisms underlying the role of EHZF in erythroid differentiation, the relationship to other transcription factors (GATA-1, GFi-1B, FOG-1 etc) which involved in erythroid differentiation.
Adaptor Protein Lnk Negatively Controls the Likelihood of Self-Renewal in Hematopoietic Stem Cells.
Authors: Ema Hideo , Seita Jun , Ooehara Jun , Iseki Akiko , Takano Hina , Nakauchi Hiromitsu 
Published: April 2020

Abstract
Great progresses are promised for the development of stem cell-based regenerative medicine if we can manipulate stem cell self-renewal. Thus, one of the central tasks in stem cell biology is to understand how stem cell fate is determined. Hematopoietic stem cells (HSCs) are the best studied stem cells. Their in vivo self-renewal has been extensively studied, but its in vitro recapitulation remains so difficult. We previously reported that HSCs undergo asymmetrical self-renewal division in culture with stem cell factor (SCF) and thrombopoietin (TPO). Since then, we have sought any condition in which HSCs can symmetrically self-renew. We now report in vitro symmetrical self-renewal division of HSCs in the absence of Lnk. Lnk is an adaptor protein containing praline-rich domain, pleckstrin homology domain, and Src homology domain. Lnk-deficient mice have over 10-fold HSCs due to increased self-renewal capacity. CD34−Kit+Sca-1+Lin− cells were purified from bone marrow of wild-type or Lnk-deficient B6 mice, and were subjected to serum-free single cell cultures in the presence of a variety of cyokines. We found that Lnk-deficient CD34−Kit+Sca-1+Lin− cells are hypersensitive to TPO. Repopulating activity in 40 CD34−Kit+Sca-1+Lin− cells from Lnk-deficient mice increased after 3 day-culture with TPO or with SCF and TPO, but not after 3 day-culture with SCF. In contrast, repopulating activity in 40 CD34−Kit+Sca-1+Lin− cells from wild type mice did not significantly change after 3 day-culture with SCF, TPO, or SCF and TPO. Moreover, paired daughter cell-experiments clearly showed that Lnk-deficient, but not wild-type long-term repopulating cells are able to undergo symmetrical self-renewal division at least once in the presence of SCF and TPO. These data suggest that Lnk acts just like a tuner in the regulation of HSC self-renewal downstream of TPO/Mpl signaling. We further investigated TPO-mediated signal transduction pathways in CD34−Kit+Sca-1+Lin− cells. To this end, we developed a novel assay which allowed us to analyze signal transduction in a very limited number of cells. We detected enhanced up-regulation of STAT5 and Akt pathways, and inversely enhanced down-regulation of p38 MAPK pathway in Lnk-deficient CD34−Kit+Sca-1+Lin− cells, as compared with normal ones. These data suggest that these combinational changes in signal transduction lead to initiation of self-renewal in HSCs. We propose that stem cell self-renewal is determined by a balance of positive and negative signals in multiple signal transduction pathways rather than by any particular self-renewal signals.
Spp1 (Osteopntin) Is Essential for the Early Niche Formation in the Bone Marrow.
Authors: Mizukami Takuo , Hamaguchi Isao , Kuramitsu Madoka , Momose Haruka , Takizawa Kazuya , Okada Seiji , Noce Toshiaki , Yamaguchi Kazunari 
Published: April 2020

Abstract
Hematopoietic stem cells (HSCs) have a potential to differentiate into variety types of blood cells, and have an ability of self-renewing in the bone marrow (BM). All these fates are regulated by intrinsic genetic pathways in the micro-enviroment (niche) where HSCs are located. Osteoblasts are thought to be the hematopoietic niche which regulates HSC function in the BM. To clarify the molecular basis of hematopoietic niche system, we compared the two somatic stem cells (Germ line stem cell (GS) and HSC) using cDNA suppression subtractive hybridization, and identified 12 stem cell-specific genes which are expressed both in the HSCs and GS. Among these genes, we analyzed Spp1, since it is a major glycoprotein produced by osteoblast and it has been reported to be a negative regulator of hematopoietic niche size in the BM.
In situ Hybridization (ISH) with Spp1-specific probes demonstrated that Spp1-expressing osteobalsts were located at the endosteal region of trabecular bone (TB). In the TB of adult mouce, Spp1-expressing hematopoietic cells attached with Spp1-expressing osteobalsts. Double ISH analysis revealed that Spp1 and Tie2 were partially co-expressed in the TB. These data suggests that Spp1 is an important molecule of hematopoietic niche system which were produced and interacted both HSCs and niche cell.
When we analyzed spp1 knock out mouse (Spp1−/−), adult Spp1−/− mice (8 weeks) appeared to be normal and fertile. However, the abnormal TB formation was observed in the younger Spp1−/− mice (2 weeks). A number of osteobalsts were increased and formed a multi-layer of osteoblasts at the endosteal region of TB. Along with the morphological change of the TB, distribution pattern of CD34, Tie2 and Bmi-1 expressing HSC was unusual. Tie2 expressing cells of Spp1−/− mouse were mainly located at vascular-enriched zone in the bone marrow, but few Tie2 expressing cells at osteoblastic zone. These data suggest that HSC and osteobalst do not form the correct niche in the Spp1−/− TB, and Spp1 is thought to be essential for the initial niche formation. To confirm the function of Spp1 at the initiation phase of niche formation, we performed the bone marrow transplantation. Mononuclear cells (1×105 cells) from Ly5.1 mice were transplanted into lethally irradiated Ly5.2 mice. At 12 days after transplantation, donor hematopoietic cells were observed in the recipient TB. At this day 12, the expression of Spp1 was up-regulated in the endosteal region of TB, however, Spp1 expression was decreased in the course of reconstitution. Thus, the findings regarding the hematopoietic niche formation in Spp1−/− mice and in the irradiated mice allow to understand the Spp1 function in the initial phase of niche formation in the bone marrow.