bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decreased TCR ζ-Chain Expression in T Cells from Patients with Aplastic Anemia.
Authors: Solomou Elena E. , Keyvanfar Keyvan , Young Neal S. 
Published: April 2020

Abstract
The ζ-chain is a unique component of the T cell receptor (TCR) with no sequence homology to other CD3 molecules. The ζ-chain acts to stabilize the TCR on the cell surface and to transmit signals to different transduction pathways in the cell. T cells from patients with autoimmune diseases, with chronic inflammation, and suffering malignant tumors are functionally impaired in that they express decreased ζ-chain. Acquired aplastic anemia (AA) is a bone marrow failure syndrome characterized by T-cell immune mediated destruction of hematopoietic stem cells. Oligoclonal expansion of T cells correlates with disease activity. In this study, we examined TCR ζ-chain protein levels in aplastic anemia patients. Twelve out of sixteen patients (75%) examined displayed decreased ζ-chain protein levels compared to normal controls (p=0.008). As a control, no differences were detected in expression of the TCR ε-chain. Patients and healthy donors displayed comparable amounts of Zap-70, the kinase responsible for full phosphorylation and activation of the ζ-chain. There was no correlation with disease status or medical treatment at the time of sampling. Four patients were re-examined for ζ-chain protein levels at 3 month intervals, but there was no change in their ζ-chain expression pattern despite hematologic improvement. We hypothesized correlation between ζ-chain and IFN-g levels in T cells from patients with AA. When we estimated IFN-g levels by flow cytometry, all 5 patients examined had increased IFN-g levels, of whom 4 had decreased ζ-chain levels: intracellular IFN-g was reciprocally correlated with ζ-chain protein levels. In summary, our data indicate that TCR ζ-chain expression is decreased in the majority of patients with AA, regardless of disease activity or treatment status. ζ-chain-deficient T cells from AA patients also overproduce IFN-g. Is ζ-chain down-regulation the primary event leading to IFN-g over-production, or is IFN-g responsible for the ζ-chain down-regulation? One possible explanation is an intrinsic defect in the TCR leading to alterations in kinases and transcription factors downstream of the ζ-chain-Zap-70 association. Whether ζ-chain expression correlates with expanded Vb clones observed is to be established. The seqeunce of molecular events described in the current work may lead to the Th1 shift observed in aplastic anemia, but further studies are needed to explore the possible role of ζ-chain downregulation to the pathogenesis of AA.
Galectin-1 Purified from Human Platelets.
Authors: Fink Nilda Ester , Gonzalez Mariana M. 
Published: April 2020

Abstract
Galectins are a family of lectins which exhibit β-galactoside-binding activity. They are Ca++-independent and have a common consensus sequence in the carbohydrate binding domain. Fourteen mammalian members of this family have been sequenced and well-characterised in different species, although galectins-1 and -3 have been the most thoroughly studied. They have biological functions in the regulation of the immune system such as allergic inflammation and host defence (activation of mast cells, neutrophils and eosinophils, stimulation of interleukins production and in the generation of oxidizing radicals), but scarse information is avalaible on biological functions in platelet function and hemostasia. The objective of this work was to detect and purified galectins from human platelets. Platelet-rich plasma obtained from blood bank, with negative serology for HIV, HBsAg and HVC, was filtered by a Pall Purecell PL filter (USA) to produce leucoreduction. Later, platelets were centrifuged and the pellet was homogenized in MEPBS (mercaptoethanol-EDTA-phosphate buffer saline)-200 mM lactose. The supernatant was treated by anion-exchange and affinity chromatography (lactose-agarose) followed by size exclusion in FPLC. We determined that an amount of 6-10 fg was present in a single platelet. The molecule was a dimer with a subunit of 14 kDa. Purified protein was isolated by PAGE-SDS and electroblotted onto nitrocellulose sheets. Identity was revealed employing polyclonal and monoclonal anti-galectin antibodies. Positive and negative controls were running simultaneously. Amino acid sequencing of galectin peptides performed indicated that it was a galectin-1. We conclude that galectin-1 is present in human platelets. Potential roles of galectin-1 in platelet function and hemostasia are under study.
New Insights from the Structure Function of the Catalytic Region of Human Platelet PDE3A: The Role of the Unique 44 Amino Acid Insert.
Authors: Hung Su-Hwi , Zhang Wei , Tao Jing , Kim Carolyn , Noone Rachel , Ezon David , Colman Roberta F. , Colman Robert W. 
Published: April 2020

Abstract
Human platelet PDE3A degrades cAMP, the major intracellular inhibitor of platelet function, and thus potentiates platelet activation. PDE3A is irreversibly inactivated by the affinity label Sp-cAMPS-BDB. The inactivation is prevented by Sp-cAMPS indicating that the affinity label is targeted at the cAMP binding site. We now use Sp-cAMPS-BDB with the aim of identifying nonconserved amino acids in substrate binding. After incubating Sp-cAMPS-BDB with PDE3A followed by reduction with [3H]NaBH4, the incorporation was 1.1 mol/mol. HPLC analysis of the tryptic digest yielded a radioactive octapeptide T806YNVTDDK813 in the 44-amino acid insert of PDE3A. Molecular modeling of PDE3A based on the PDE3B structure suggests the insert is a flexible loop. Incorporation of Sp-cAMPS-BDB indicates loop interaction with the substrate. Since Sp-cAMPS-BDB reacts with the nucleophilic residues, Y807, D811 and D812 were each mutated to alanine. Sp-cAMPS-BDB inactivates D811A and D812A but not Y807A, suggesting Y807 is the residue modified by Sp-cAMPS-BDB. Y807A affects the Km but not kcat, suggesting its involvement in cAMP binding. Kinetic analyses of 11 loop mutants reveal that H782A, T810A, Y814A and C816S each affects the kcat but not Km, indicating that catalysis is modulated. We conclude that binding of cAMP to the flexible loop of platelet PDE3A induces a conformational change which allows interaction with essential catalytic residues. These findings provide a new strategy for developing antiplatelet agents to treat patients with reocclusion of coronary arteries who are resistant to aspirin or whose chronic congestive heart failure prevents utilizing cilostazol.
Proteomic Analysis Reveals Intrinsic Differences between Phenotypically Identical Mesenchymal Stem Cells.
Authors: Mazhari Sam , Desai Jyoti , Chamberlain Jason , Porada Chris , Zanjani Esmail D. , Almeida-Porada Graca 
Published: April 2020

Abstract
We have previously reported the isolation of Stro-1+, CD45-, GlyA-human MSC from human bone marrow (BM), liver (LV), and brain (BR). Despite their similar morphology and phenotype, these cells, upon in vivo transplantation into the pre-immune fetal sheep model, seemed to differentiate more efficiently into cells of their tissue of origin. For instance, all 3 sources of MSC gave rise to blood, with average levels of human CD45+ cells in chimeric animals of 8.7% for LVMSC, 3.3% for BRMSC, and 4.5%for BMMSC. Human neural cells were also detected in the brain of transplanted animals with the highest levels obtained with BRMSC (1.33%) and lowest with LVMSC (0.4%). However, BRMSC generated very few human hepatocytes (2–10 hepatocytes/section), while both LVMSC and BMMSC gave rise to much higher levels of hepatocytes. This led us to hypothesize that despite the similar phenotype, the proteome makeup of MSC from different tissues may be distinct. To test this hypothesis, we examined the commonalities and differences in the protein repertoire of cultured MSC from these 3 different sources. The eighty most prominent protein spots from the 2-D gel of each cell population were removed and identified by MOLDI-TOF/TOF mass spectroscopy after Trypsin digestion. Our results demonstrate that there are a large number of common proteins between the LV, BM and BR MSC (&gt; 75%). Besides the cytoskeletal and associative proteins such as Vimentin, β-actin, cofilin, Tropomyosin and Lamin A/C, the cells contained a large quantity of proteins for protein processing such as Cyclophilin A, Endoplasmic reticulum protein ERp29, Disulfide-isomerase ER60 and Glucose-regulated proteins 75 and 78, which may be important for the broad differentiative potential of MSC. Despite these similarities, forty percent of the identified proteins showed significantly different expression levels between the three types of cells (&gt; 300%), the majority of which were not proteins previously shown to be BM-, Liver or Brain-specific. Interestingly, however, LV-derived cells contained a 5-fold greater concentration of Albumin than BM or Brain cells, which may explain their greater tendency to form liver tissue in vivo. Likewise, since BMMSC were enriched in smooth muscle associated proteins, potentially they may constitute a better source to be used for muscle repair. Thus, the definition of the different MSC proteomes can lead not only to the discover of critical differences involved in differentiation/plasticit into different cell fates, but may also help us to identify distinct cell populations that are ideally suited for cell therapies for specific organs.
Identification of Inherited Macrothrombocytopenias Based on Mean Platelet Volume among Patients Diagnosed with Idiopathic Thrombocytopenia.
Authors: Gohda Fumito , Uchiumi Hideki , Handa Hiroshi , Takafumi Matsushima , Tsukamoto Norifumi , Morita Kimio , Amagai Hatsuo , Murakami Masami , Murakami Hirokazu , Nojima Yoshihisa , Karasawa Masamitsu 
Published: April 2020

Abstract
Inherited macrothrombocytopenia is a rare illness that is often misdiagnosed as idiopathic thrombocytopenia (ITP), a more widespread acquired disease. The hallmark of a diagnosis of these diseases is the presence of giant platelets. Automated blood cell counters in routine clinical use usually miss giant platelets and underestimate mean platelet volume (MPV). Incorrect diagnoses might expose patients to a risk of unnecessary treatment. The ADVIA 120 hematology counter efficiently detects large platelets based on two-dimensional laser light scatter. This two-dimensional approach provides a more accurate estimation of platelet volume than conventional one-dimensional analysis. The present study measures and re-evaluates MPV using the ADVIA 120 in 112 patients who had initially been diagnosed with ITP.
We identified 11 unrelated patients as having probable macrothrombocytopenia (average MPV of 19.2 ± 3.8 fL; normal range 7.8–10.2). A diagnosis of inherited macrothrombocytopenia was immediately ruled out in 5 of the 11 patients, because their medical records indicated that their platelet counts had once been normal or became normalized (&gt;100x199/L) in response to steroid therapy. Of the remaining 6 patients, platelets aggregated abnormally in response to ristocetin in 3 patients and MYH9-RD was suspected in one patient since Döhle-like bodies were apparent in granulocytes on blood films. DNA analyses confirmed that 3 of these patients had Bernard-Soulier syndrome and 1 had MYH9-related disease, both of which are the most common forms of inherited macrothrombocytopenia. We detected 3 homozygous mutations in the 3 patients with Bernard-Soulier syndrome: A3171T and 4444insT in the GPIbα gene that created new premature termination codons, and the missense mutation, G1913A in the GPIX gene, that caused the loss of GPIX surface expression. In one patient with MYH9-related disease, we found a heterozygous missense mutation of C5797T in exon 40 of the MYH9 gene. We stress that all four patients had received high-dose steroid therapy and/or splenectomy before this study according to a diagnosis of ITP.
Checking MPV using the ADVIA 120 in thrombocytopenic patients is a useful method of correctly diagnosing inherited macrothrombocytopenia, and thus avoiding patient exposure to unnecessary and sometimes toxic treatment.
Interaction of Recombinant Factor VIIa with Rehydrated, Lyophilized Platelets.
Authors: Fischer Thomas H. , Wolberg Alisa S. , Bode Arthur P. , Ramer Kevin J. , Nichols Timothy C. 
Published: April 2020

Abstract
The experiments presented here were undertaken to determine if factor VIIa (rFVIIa, the Novo Nordisk product NovoSeven™) will directly bind to rehydrated, lyophilized (RL) platelets (Stasix™ platelets, Entegrion, Inc. trade) for the formation of a catalytic surface with an enhanced ability to generate thrombin. The relationship of rFVIIa to the RL platelet surface was examined by measuring equilibrium and non-equilibrium binding of the coagulation factor to the cells, by studying the subcellular localization of the coagulation factor on RL platelets, and by following the effects of the surface modification on the kinetics of thrombin generation. The association of rFVIIa with RL platelets occurred with an on rate of 3.6x103 sec−1moles−1. Saturation occurred in minutes and was calcium dependent. Disassociation (in plasma or citrated saline) was slow, with over half of the coagulation factor remaining bound after two hours (with slow and fast rate constants of 5.0x10−5 and 4.1x10−4 sec−5 respectively). These results define a binding site with an apparent equilibrium constants of 110 nM. Equilibrium binding of rFVIIa to RL platelets was analyzed with flow cytometry and Western analysis. The rFVIIa was bound to RL platelets in a dose-dependent manner when incubated at concentrations of 0.3 to 10.0 uM rFVIIa and 3x104 to 106 RL platelets/ul in citrated saline. When high concentrations of rFVIIa were bound to RL platelets densities of over one million molecules of rFVIIa per RL platelet was obtained. Fluorescent microscopy analysis revealed that the rFVIIa was localized to the surface membrane and that some rFVIIa localized internally to the outer surface of the surface connected open canalicular system and/or sites of internal trafficking. Flow cytometric analysis with annexin V demonstrated that considerable quantities of phosphatidylserine were present on the external surface of the RL platelet membrane for potential facilitation of rFVIIa binding. The effect of RL platelet surface modification by rFVIIa on thrombin generation was investigated by following the hydrolysis of the thrombin-specific fluorogenic substate D-phe-pro-arg-ANSNHin plasma. rFVIIa and RL platelets accelerated thrombin generation in this system with rFVIIa being approximately twice as effective (per molecule of the recombinant protein) when added to the assay system pre-bound to RL platelets as compared to being initially free in the plasma. Similar results were obtained when free and RL platelet bound rFVIIa were tested in factor IX-deficient plasma. These experiments show that rFVIIa retains activity when super-saturated on the RL platelet membrane. The results of the studies presented here suggest that RL platelets can be used to concentrate rFVIIa at sites of vascular injury.
Diagnostic Criteria for Hematopoietic Stem Cell Transplantation-Associated Microangiopathy (TAM): Results of a Consensus Process by an International Working Group.
Authors: Ruutu Tapani , Barosi G. , Benjamin R. J. , Clark R. E. , George J. N. , Gratwohl A. , Holler E. , Iacobelli M. , Kentouche K. , Lämmle B. , Moake J. L. , Richardson P. , Socié G. , Zeigler Z. , Niederwieser D. , Barbui T. 
Published: April 2020

Abstract
The pathogenesis of microangiopathy following stem cell transplantation is poorly understood. Endothelial injury is probably an important factor. The spectrum of transplantation-associated microangiopathy (TAM) extends from minor laboratory findings to life-threatening clinical complications. TAM has not been properly defined, a large number of definitions have been used, and the reported incidences and outcomes of this complication have varied greatly. For purposes of clinical study, and to hasten the development of prophylaxis and therapy for this complication, widely accepted and uniform criteria for TAM are essential. An International Working Group was, therefore, formed with the goal of developing a consensus formulation of the criteria necessary for the diagnosis of TAM. Using a mail-only process, 14 experts in microangiopathic disorders and/or transplantation were asked to propose a list of candidate diagnostic criteria, to select those considered necessary, and to rank those considered optional in order to identify a core set of criteria. The three necessary criteria in the core set consisted of: 1)”increased percentage (&gt;4%) of schistocytes in the blood”; 2)”de novo, prolonged, or progressive thrombocytopenia (platelet count ≤50x109/l or a 50% or greater reduction from previous counts)”; and 3)”sudden and persistent increase in LDH”. The four most highly ranked optional criteria were: “decrease in Hb concentration or increased red cell transfusion requirement”, “decrease in serum haptoglobin”, “sudden and persistent increase in BUN or creatinine”, and “neurological symptoms”. In an appropriateness panel process, the experts were then asked to score the diagnosis of 16 patient profiles as appropriate or not appropriate for TAM. Using the experts’ consensus, the performance (sensitivity and specificity) of 24 possible definitions of the disorder obtained from the core set of criteria was evaluated. The definition of TAM with the highest final score was: the three necessary criteria, plus decrease in Hb concentration or increased red cell transfusion requirement plus decrease in serum haptoglobin. The Working Group, consequently, proposes that the diagnosis of TAM requires fulfilment of all of the following criteria: 1) increased percentage (&gt;4%) of schistocytes in the blood; 2) de novo, prolonged, or progressive thrombocytopenia (platelet count ≤50x109/l or 50% or greater reduction from previous counts); 3) sudden and persistent increase in LDH; 4) decrease in Hb concentration or increased red blood cell transfusion requirement; and 5) decrease in serum haptoglobin. This definition has &gt;80% sensitivity and specificity.
The Clinical Efficacy of Helicobacter pylori Eradication in Patients with Helicobacter pylori-Positive Chronic Thrombocytopenic Purpura.
Authors: Nam Seung-Hyun , Kim Bong-Seog , Lee Jae Hoon , Song Hong Suk , Bae Sung-Hwa , Hyun Myung Soo , Yuh Young Jin , Lee Sang-Jae , Park Seonyang 
Published: April 2020

Abstract
Background: Helicobacter pylori (H pylori) has been implicated in the pathogenesis of some autoimmune diseases including idiopathic thrombocytopenic purpura (ITP). Several studies recently showed a high prevalence of H pylori infection in patients with ITP and reported a platelet recovery after bacterial eradication therapy. The prevalence of H pylori infection and effect of its eradication in Korea patients with chronic ITP were investigated.
Methods: The study included among 35 patients with chronic ITP from eight hospitals. H pylori infection was assessed by urea breath test, rapid urease test or microbial culture. H pylori eradication was performed with amoxicillin, clarithromycin and omeprazol regimen for 7 days or bismuth, metronidazol and tetracycline regimen for 10 days. Eradication was assessed by urea breath test 4 weeks after treatment. Platelet counts were monitored serially after the end of treatment.
Results: Thirty five patients with chronic ITP were evaluated, including 12 males and 23 females. Median age was 57 years (range 30–79). The median platelet count before eradication was 23,000/uL (range 4,000–66,000/uL). Sixteen patients were performed the splenectomy previously. H pylori infection was found in 23 (65%) of 35 patients. In 21 patients performed the eradication, 6 patients (28.5%) had a significant increase in platelet count after 2 weeks and 2 months. The response duration was 1–27 (median 7.6) months.
Conclusions: This study confirmed the efficacy of H pylori eradication in increasing platelet in adult chronic ITP patients. We must consider the investigation and eradication of H pylori infection in ITP patients as a simple, inexpensive tool in management of the chronic disease.
Correlation between Helicobacter Pylori Eradication and Platelet Count in Immune Thrombocytopenic Purpura (ITP).
Authors: Jang Jun Ho , Kim Hyeoung Il , Lee Hyun Woo , Kang Seok Yun , Park Joon Seong , Choi Jin Hyuk , Lim Ho Yeong , Kim Hugh C. 
Published: April 2020

Abstract
BACKGROUND: Helicobacter pylori has clearly been implicated in the pathogenesis of gastric and duodenal ulcers, gastritis, and gastric malignancy. Remarkably, eradication of H. pylori from the gastric mucosa has been associated with improvement of systemic disease, including Sjögren’s syndrome, rheumatoid arthritis, autoimmune thyroid disease, and immune thrombocytopenic purpura (ITP).
PURPOSE: To investigate the relationship between Helicobacter pylori infection and the clinical features of idiopathic thrombocytopenic purpura (ITP), and to examine the effects of H. pylori eradication on platelet counts.
METHOD: A 13C urea breath test (UBT) for H. pylori infection was performed in a 25 consecutive patients with ITP at Ajou University School of Medicine, Suwon, Korea. Patients who tested positive for H. pylori received standard eradication therapy if their platelet count was &lt; 50 x 109/L.
RESULTS: H. pylori infection was detected in 18 patients (72%) and eradication therapy was successfully administered to all infected patients. H. pylori infection was not associated with dyspepsia or other clinical or laboratory features. Platelet responses were observed in 6 (33%) of these patients, which lasted for more than 4 months in 4 patients. Platelet associated antibody and anti platelet antibody were negative to all patients.
CONCLUSION: H. pylori eradication may improve the platelet counts in some of adults (33%) in whom the ITP is of recent onset.