Decrease In Number Of Platelets Research Articles

α-Actinin-1 deficiency in megakaryocytes causes low platelet count, platelet dysfunction, and mitochondrial impairment.

Cytoskeletal remodeling and mitochondrial bioenergetics play important roles in thrombocytopoiesis and platelet function. Recently, α-actinin-1 mutations have been reported in patients with congenital macrothrombocytopenia. However, the role and underlying mechanism of α-actinin-1 in thrombocytopoiesis and platelet function remain elusive. Using MK-specific α-actinin-1 knockout (PF4-Actn1-/-) mice, we demonstrated that PF4-Actn1-/- mice exhibited reduced platelet counts. The decreased platelet number in PF4-Actn1-/- mice was due to defects in thrombocytopoiesis. H&E staining and flow cytometry revealed a decrease in the number of MKs in the bone marrow of PF4-Actn1-/- mice. The absence of α-actinin-1 increased the proportion of 2 N-4 N MKs and decreased the proportion of 8 N-32 N MKs. CFU-MK colony formation, the ratio of proplatelet formation-bearing MKs, and MK migration in response to SDF-1 signaling were inhibited in PF4-Actn1-/- mice. Platelet spreading, clot retraction, aggregation, integrin αIIbβ3 activation, and P-selectin exposure in response to various agonists were decreased in PF4-Actn1-/- platelets. Notably, PF4-Actn1-/- platelets inhibited calcium mobilization, ROS generation, and actin polymerization in response to collagen and thrombin. Furthermore, the PF4-Actn1-/- mice exhibited impaired hemostasis and thrombosis. Mechanistically, proteomic analysis of low-ploidy (2-4 N) and high-ploidy (≥8 N) PF4-Actn1-/- MKs revealed that α-actinin-1 deletion reduced platelet activation and mitochondrial function. PF4-Actn1-/- platelets and Actn1 KO 293T cells exhibited reduced mitochondrial membrane potential, mitoROS generation, mitochondrial calcium mobilization, and mitochondrial bioenergetics. Overall, in this study, we report that mice with α-actinin-1 deficiency in MKs exhibit low platelet count and impaired platelet function, thrombosis, and mitochondrial bioenergetics.

Comparing the coagulation and platelet parameters of womenwith premature ovarian insufficiency with those of age-matched controls: A case-control study.

This study aimed to compare the coagulation and platelet parameters in women with spontaneous premature ovarian insufficiency (POI) with those in age-matched controls. This case-control study recruited 202 women with POI and 202 age-matched women with benign gynecological diseases as controls. Coagulation parameters, including prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (APTT), and thrombin time (TT), fibrinogen, and platelet parameters, including platelet count (PLT), mean platelet volume (MPV), plateletcrit (PCT), and platelet distribution width (PDW), were compared between women with POI and controls. Factors associated with coagulation and platelet parameters were also analyzed in women with POI. In women with POI, higher fibrinogen levels and PDW, lower PLT, MPV, and PCT levels, and shorter TT were observed (p < 0.001). Linear regression analysis further revealed that women with POI were more likely to exhibit increased serum fibrinogen levels (β = 0.465, 95% confidence interval [CI] 0.366-0.564) and PDW (β = 0.340, 95% CI 0.300-0.379), decreased TT (β = -1.101, 95% CI -1.233--0.969), PLT (β = -50.985, 95% CI -65.087--36.882), MPV (β = -1.498, 95% CI -1.875 to -1.120), PCT levels (β = -0.084, 95% CI -0.095--0.973). Additionally, follicle-stimulating hormone levels were positively associated with fibrinogen levels in women with POI. There were no statistically significant differences in PT, INR, and APTT between women with POI and controls. Women with POI exhibited decreased platelet numbers, abnormal platelet morphology, and elevated fibrinogen concentrations, potentially implicating POI's etiopathogenesis or contributing to an increased risk of cardiovascular disease in women with POI. No coagulation abnormalities were observed in women with POI.

A Gain-of-Function Mutation in the Ca2+ Channel ORAI1 Causes Stormorken Syndrome with Tubular Aggregates in Mice.

Store-operated Ca2+ entry (SOCE) controls Ca2+ homeostasis and mediates multiple Ca2+-dependent signaling pathways and cellular processes. It relies on the concerted activity of the reticular Ca2+ sensor STIM1 and the plasma membrane Ca2+ channel ORAI1. STIM1 and ORAI1 gain-of-function (GoF) mutations induce SOCE overactivity and excessive Ca2+ influx, leading to tubular aggregate myopathy (TAM) and Stormorken syndrome (STRMK), two overlapping disorders characterized by muscle weakness and a variable occurrence of multi-systemic anomalies affecting spleen, skin, and platelets. To date, different STIM1 mouse models exist, but only a single ORAI1 mouse model with muscle-specific TAM/STRMK phenotype has been described, precluding a comparative analysis of the physiopathology in all affected tissues. Here, we generated and characterized mice harboring a prevalent ORAI1 TAM/STRMK mutation and we provide phenotypic, physiological, biochemical, and functional data. Examination of Orai1V109M/+ mice revealed smaller size, spleen enlargement, reduced muscle force, and decreased platelet numbers. Morphological analyses of muscle sections evidenced the presence of tubular aggregates, the histopathological hallmark on biopsies from TAM/STRMK patients absent in all reported STIM1 models. Overall, Orai1V109M/+ mice reliably recapitulate the human disorder and highlight the primary physiological defects caused by ORAI1 gain-of-function mutations. They also provide the possibility to investigate the formation of tubular aggregates and to develop a common therapy for different TAM/STRMK forms.

Toxicological assessment of the aqueous extract of Juniperus oxycedrus L. on acute and subacute toxicities in rats

Juniperus oxycedrus L. (J. oxycedrus) has a rich historical background in herbal remedies to treating digestive system abnormalities. However, no comprehensive evaluation of its potential toxic effects has been conducted. The current investigation aimed to evaluate the acute and subacute toxicity of an aqueous extract of J. oxycedrus (AEJO). AEJO was prepared by the conventional Moroccan methods by decoction the arial part of the plant. The acute and subacute toxicity tests were conducted in mice and rats, respectively. Acute toxicity tests showed that the extract was not toxic even at high doses of 5000 mg/kg. In the subacute study, no detectable indications of toxicity or mortality were observed and there were no notable deviations in food intake or water consumption among all rats. However, changes in body weight of animals treated with 1000 and 2000 mg/kg underwent a significant decrease. AEJO administration decreased platelet number, elevated levels of alanine aminotransferase and alkaline phosphatase, and reduced albumin levels. Histological examination revealed normal renal parenchyma despite increased creatinine. It also showed binucleation, and hepatocyte vacuolation. The results indicate that AEJO has considerable tolerance for consumption, but repeated use can affect hepatocytes and kidneys. Therefore, additional analyses, such as subchronic, chronic, and neurotoxic studies, are required before using this plant in clinical research.

Immune Thrombocytopenia in Children

Immune thrombocytopenia is a hematological disorder defined by an isolated decrease in platelet numbers. We present a retrospective-descriptive study that enrolls twenty-five children (aged 0-18 years old) admitted to Brasov Children’s Hospital from the 1st of January 2020 until the 1st of September 2023 with the diagnosis of idiopathic thrombocytopenic purpura (ITP).&#x0D; We could find proof of recent viral infection in seven patients out of twenty-five; three of them also had immunological findings- positive antinuclear, positive direct Coombs test, or antiplatelet antibodies. The medical literature mentions glucocorticoids and IVIG therapy as the first line of treatment for immune thrombocytopenic purpura, while new pharmaceutical agents are still under review.

Qing-Fei-Pai-Du Decoction ameliorated coagulopathy and thrombocytopenia in endotoxaemia rats and enhanced platelet production from megakaryocytes

BackgroundsThe Qing-Fei-Pai-Du Decoction (QFPDD) was reported to ameliorate the inflammatory coagulopathy and thrombocytopenia in COVID-19 patients. This work investigated the effects of QFPDD in endotoxaemia rats and then further studied its influence on platelet production using cultured megakaryocytes. MethodsThe coagulation indexes and platelet aggregation reactivity of LPS-induced endotoxemia rats with or without QFPDD treatment were analyzed. The platelet parameters, the expression of thrombopoietin (TPO) in the liver and the kidney, number of the megakaryocytes in bone marrow smear of rats were checked. The maturation and platelet production of human megakaryoblastic MEG-01 cells treated with QFPDD or isochlorogenic acid A (ISA), an active component of QFPDD, were observed. ResultsQFPDD improved the coagulation indexes of LPS-induced endotoxaemia rats and decreased the hyper-reactivity of platelets. QFPDD ameliorated LPS-induced decrease in platelet number, partially alleviated increase in liver TPO expression and exhibited no influence on increase in the number of bone marrow megakaryocytes. QFPDD promoted maturation and production of platelet-like particles of MEG-01 megakaryocytes. The effects of QFPDD on MEG-01 megakaryocytes might be related to activation of AKT pathway and up-regulation of related transcription factors. ISA also could induce the maturation of MEG-01 cells. ConclusionsQFPDD effectively ameliorated coagulopathy and thrombocytopenia in rats under inflammatory state. The mechanisms of QFPDD in ameliorating thrombocytopenia might be based on both decreasing effects on platelet depletion in coagulation and inducing effects on maturation and platelet production of megakaryocytes. ISA might be one of the components which contribute to the effects of QFPDD on megakaryocytes.

Effect of Hetrombopag Combined with Rhtpo in Patients with Severe Immune Thrombocytopenia

Background: Severe Immune Thrombocytopenia (ITP) is a life-threatening acquired hemorrhagic disease with dramatically decreased platelet number and clinical bleeding symptoms. Some patients with severe ITP did not respond to first-line treatment including steroids and Intravenous Immunoglobulin (IVIG). It was critical for them to use effective treatments to promote platelet and reduce the risk of fatal bleeding. Clinical practice guidelines have recommended the use of thrombopoietin receptor agonist (TPO-RA) as a second-line treatment for ITP. Recombinant human thrombopoietin (rhTPO) and hetrombopag are two distinct TPO-RAs with different mechanisms. As reported, there remains no study assessing the efficacy and safety of hetrombopag combined with rhTPO in the treatment of ITP. Therefore, the present study aimed to investigate the efficacy of hetrombopag plus rhTPO in Chinese patients with severe ITP, focusing on the short rather than the long-term efficacy, such as quickly increasing platelet count and significantly reducing bleeding, which would be more meaningful for severe patients whose platelet count &amp;lt;10 × 10 9/L. Methods: This was a prospective, open-label, single-center study with a planned enrollment of 30 patients. The inclusion criteria were patients ≥ 18 years, diagnosed with primary immune thrombocytopenia, platelet count &amp;lt;10 × 10 9/L, or bleeding score ≥ 5. Patients receiving other ITP drugs as maintenance therapy were eligible if previous glucocorticoid therapy doses were stable, and rituximab was used for at least 2 months and other immunosuppressants were stable for at least 4 weeks. Patients who had received IVIG, avatrombopag, eltrombopag, or romiplostim within 2 weeks prior to enrollment were excluded. Histories of platelet transfusion one week before treatment were excluded. Hetrombopag was given at 5 mg/day for 28 days, while rhTPO was administered at 300 U/kg subcutaneously daily for 14 days. When PLT &amp;gt; 100 × 10 9/L, rhTPO should be discontinued. When PLT &amp;gt; 150 × 10 9/L, the dosage of hetrombopag was reduced to 2.5mg/day, and it would be discontinued if PLT &amp;gt; 250 × 10 9/L. The primary endpoints were proportion of subjects with platelet count ≥30×10 9/L and at least doubled the baseline platelet count within 28 days. Secondary endpoints included bleeding score, incidence of thrombotic events, and adverse events (AEs). Results: As to July 27, 2023, a total of 20 patients were included in this study, with a median age of 36 years and a male proportion of 50%. Among them, 70% (14 cases) were newly diagnosed ITP patients. 50% of patients have received ≥ 1 line of previous treatment, of which 2 patients have received IVIG treatment and both have achieved CR (PLT ≥ 100 × 10 9/L). The baseline median platelet count was 5 × 10 9/L, and 95% (19 cases) of patients had active bleeding with a bleeding score of ≥ 1 point. The median duration for hetrombopag at dose of 5mg is 8.0 days, and rhTPO is 6.5 days. After combined treatment, the median time for platelet counts reached 30, 50, and 100 × 10 9/L was 4.5 days, 6 days, and 7 days, respectively. Among them, the median platelet count reached 103 × 10 9/L after 7 days treatment and 214.5 × 10 9/L after 15 days. Within 15 days of combined treatment, 15% (3 cases) of patients achieved partial platelet reaction (PLT &amp;gt; 50 × 10 9/L, without bleeding), and 85% (17 cases) achieved complete platelet reaction (PLT &amp;gt; 100 × 10 9/L, without bleeding). In terms of safety, two patients experienced liver function abnormalities, both of which were grade 1-2. One was related to treatment drugs, and the other was associated with underlying autoimmune liver disease. No thrombotic events occurred in all patients. Conclusion: This study innovatively explores the efficacy and safety of combination therapy with hetrombopag and rhTPO in the treatment of severe ITP. It is preliminarily confirmed that this combination therapy can effectively and quickly improve the early platelet response of ITP patients, avoid bleeding damage, and is expected to become a new treatment choice for severe ITP patients. We also look forward to the overall efficacy evaluation results of all patients after completing treatment in the future.

Mice Lacking α-Actinin-1 in Megakaryocytes Display the Feature of Thrombocytopenia and Impair Platelet Functions

Cytoskeleton remodeling and mitochondrial bioenergetics play important roles in platelet biogenesis and functions. α-Actinin-1, a filament crosslinker, was widely expressed in nonmuscle cells, including megakaryocytes (MKs) and platelets. The cytoskeleton is essential for normal mitochondrial morphology, motility, and distribution. In recent years, the accumulated evidence suggests that inherited mutations in α-actinin-1 are implicated in congenital macrothrombocytopenia. However, the role and underlying mechanism of α-actinin-1 in platelet biogenesis and platelet functions remain poorly studied. In this study, we generated an MK-specific α-actinin-1 knockout mouse model (referred to herein as PF4- Actn1-/-) to investigate the contribution of α-actinin-1 in platelet biogenesis and functions. Blood count tests showed that PF4- Actn1-/- mice exhibited reduced platelet counts. The decreased platelet number in PF4- Actn1-/- mice was not attributed to accelerated platelet clearance or impaired TPO generation in vivo. Platelet count changes observed in an anti-GPIbα antibody-induced thrombocytopenia model and splenectomy indicated that the diminished platelet counts in PF4- Actn1-/- mice might be due to defects in platelet biogenesis. Compared to control mice, PF4- Actn1-/- mice had normal numbers of MK progenitors, including in LSK, MPP, CMP, GMP, MEP, and PreMegE. H&amp;E staining and flow cytometry revealed a decrease in the number of MKs in BM, but an increase in the number of MKs in the spleen. The absence of α-actinin-1 significantly increased the proportion of 2N-4N MKs and decreased the proportion of 8N-32N MKs. CFU-MK colony formation and MK migration in response to SDF-1 signaling was inhibited in PF4- Actn1-/- mice. Furthermore, in vitro studies showed a reduced ratio of PPF-bearing MKs in fetal liver-derived PF4- Actn1-/- MKs. Collectively, these data suggest that α-actinin-1 deficiency in mouse MKs could impair platelet biogenesis, resulting in thrombocytopenia in PF4- Actn1-/- mice. Platelet adhesion and spreading on immobilized fibrinogen and collagen, thrombin-stimulated clot retraction, and platelet aggregation in response to various concentrations of ADP, thrombin, and collagen was significantly decreased in PF4- Actn1-/- platelets. PF4- Actn1-/- platelets also exhibited decreased integrin αIIbβ3 activation and reduced P-selectin exposure in response to various concentrations of ADP, ADP+EPI, thrombin, collagen, and convulxin. Notably, PF4- Actn1-/- platelets showed inhibited calcium mobilization, reactive oxygen species (ROS) generation, and actin polymerization in response to collagen and thrombin. Furthermore, PF4- Actn1-/- mice demonstrated significantly impaired hemostasis. No differences were observed in the PT, APTT, TT, and fibrinogen concentrations between PF4- Actn1-/- mice and Actn1f/f mice. However, tail, liver, and brain bleeding tests revealed that PF4- Actn1-/- mice had significantly prolonged bleeding time and increased bleeding volume. Kaolin-activated whole thromboelastography (TEG) mapping assay indicated that there were no differences in the R-time, K-time, and α-angle values, but the maximum amplitude was decreased in PF4- Actn1-/- mice. To explore the mechanism of α-actinin-1 in platelet biogenesis and platelet functions. Low- (2-4N) and high-ploidy (≥8N) Actn1f/f and PF4- Actn1-/- MKs were sorted for quantitative proteomics analysis. The results of 4D label-free quantitative proteomics revealed that protein expression was significantly decreased in high-ploidy MKs following α-actinin-1 knockdown. Functional enrichment analysis of differentially expressed proteins indicated that α-actinin-1 deletion reduced platelet activation and mitochondrial functions. PF4- Actn1-/- platelets exhibited reduced mitochondrial membrane potential, mitochondrial ROS generation, mitochondrial respiration and glycolysis, suggesting alterations in mitochondrial function in platelets. In this study, we report that mice with α-actinin-1 deficiency in MKs recapitulate the features of thrombocytopenia and exhibit impaired platelet functions.

Predictors of an unfavorable course of COVID-19

The aim of the study was to identify the features of the unfavorable clinical course of a new coronavirus infection.Material and methods. The analysis of clinical data, laboratory results and comorbidity of 168 patients with a confirmed diagnosis of a new coronavirus infection aged 65,0 [57,0; 74,0] years was carried out. Two groups of patients were distinguished – 126 persons with a moderate course and with clinical recovery in the outcome of the disease and 42 persons with a severe course and a fatal outcome of the disease. Transnosological polymorbidity was assessed by the average number of nosologies corresponding to the three-digit ICD-10 rubricification, transsystemic – by the number of affected systems. Hemogram parameters, blood content of C-reactive protein, creatinine, urea, glucose, prothrombin index, international normalized ratio, activated partial thromboplastin time, platelet count, D-dimer concentration were estimated.Results. In the group of patients with fatal outcomes, compared to patients with recovery, there were statistically significantly higher indices of transnosological and transsystemic polymorbidity (1.5 and 2 times, respectively), they were more likely to have ischaemic heart disease, myocardial infarction, transient ischemic attack in anamnesis, atrial fibrillation, chronic heart failure; blood concentration of C-reactive protein, fasting glucose, urea, D-dimer in the blood serum was higher, the number of thrombocytes was less.Conclusions. A high degree of transnosological and transsystemic polymorbidity, a history of myocardial infarction and transient ischemic attack, comorbid chronic heart failure, atrial fibrillation, an increase in D-dimer, CRP content, and a decrease in platelet number are predictors of severe course and the lethal outcome of COVID-19.

Over-expression of Dyrk1A affects bleeding by modulating plasma fibronectin and fibrinogen level in mice.

Down syndrome is the most common chromosomal abnormality in humans. Patients with Down syndrome have hematologic disorders, including mild to moderate thrombocytopenia. In case of Down syndrome, thrombocytopenia is not associated with bleeding, and it remains poorly characterized regarding molecular mechanisms. We investigated the effects of overexpression of Dyrk1A, an important factor contributing to some major Down syndrome phenotypes, on platelet number and bleeding in mice. Mice overexpressing Dyrk1A have a decrease in platelet number by 20%. However, bleeding time was found to be reduced by 50%. The thrombocytopenia and the decreased bleeding time observed were not associated to an abnormal platelet receptors expression, to a defect of platelet activation by ADP, thrombin or convulxin, to the presence of activated platelets in the circulation or to an abnormal half-life of the platelets. To propose molecular mechanisms explaining this discrepancy, we performed a network analysis of Dyrk1A interactome and demonstrated that Dyrk1A, fibronectin and fibrinogen interact indirectly through two distinct clusters of proteins. Moreover, in mice overexpressing Dyrk1A, increased plasma fibronectin and fibrinogen levels were found, linked to an increase of the hepatic fibrinogen production. Our results indicate that overexpression of Dyrk1A in mice induces decreased bleeding consistent with increased plasma fibronectin and fibrinogen levels, revealing a new role of Dyrk1A depending on its indirect interaction with these two proteins.

Matrix stiffness controls megakaryocyte adhesion, fibronectin fibrillogenesis, and proplatelet formation through Itgβ3

AbstractMegakaryocytes (MKs) are the precursor cells of platelets, located in the bone marrow (BM). Once mature, they extend elongated projections named proplatelets through sinusoid vessels, emerging from the marrow stroma into the circulating blood. Not all signals from the microenvironment that regulate proplatelet formation are understood, particularly those from the BM biomechanics. We sought to investigate how MKs perceive and adapt to modifications of the stiffness of their environment. Although the BM is one of the softest tissue of the body, its rigidification results from excess fibronectin (FN), and other matrix protein deposition occur upon myelofibrosis. Here, we have shown that mouse MKs are able to detect the stiffness of a FN-coated substrate and adapt their morphology accordingly. Using a polydimethylsiloxane substrate with stiffness varying from physiological to pathological marrow, we found that a stiff matrix favors spreading, intracellular contractility, and FN fibrils assembly at the expense of proplatelet formation. Itgb3, but not Itgb1, is required for stiffness sensing, whereas both integrins are involved in fibrils assembly. In contrast, soft substrates promote proplatelet formation in an Itgb3-dependent manner, consistent with the ex vivo decrease in proplatelet formation and the in vivo decrease in platelet number in Itgb3-deficient mice. Our findings demonstrate the importance of environmental stiffness for MK functions with potential pathophysiological implications during pathologies that deregulate FN deposition and modulate stiffness in the marrow.

Recipient-Specific Antibodies (RSA) in Mismatched Related Transplants May Induce Transplant-Associated Thrombotic Microangiopathy (TA-TMA)

HLA incompatibility increases the risk of transplant-related complications. Specifically, donor-specific antibodies (DSA) in mismatched related transplants (mm-HCT) increase the risk of graft failure. Less is known about the role of recipient-specific antibodies (RSA) detected in donors, as the immune status of the donor is not routinely examined before transplant with regard to anti-HLA antibodies. These antibodies may be transferred together with transplanted cells or produced by memory donor cells. We hypothesize that donor-derived RSA may induce immune-mediated complement activation in the classical pathway (CH50), leading to overproduction of membrane attack complex (MAC) and exacerbation of endothelial damage. Here we present preliminary epidemiological data regarding the presence of DSA and RSA, and the impact of RSA antibodies on transplant-related complications, especially transplant-associated thrombotic microangiopathy (TA-TMA) and acute graft-versus-host disease (aGvHD). Methods We prospectively analyzed the presence of anti-HLA antibodies in 20 pairs of donors and recipients qualified for mm-HCT. All recipients suffered from hematological malignancies and received a myeloablative conditioning regimen and immunosuppression consisting of post-transplant cyclophosphamide, tacrolimus, and mycophenolate mofetil. Patients’ and donors’ immunization status were tested with the solid phase method. Tests were carried out using a flow fluorometer across the screening range (Luminex Screen, One Lambda, USA). In the group of positive samples for anti-HLA class I and/or II antibodies, identification of the specificity of the HLA antibodies was performed (Luminex Single Antigen Beads, One Lambda, USA). Reagents enabling the determination of anti-HLA antibodies in the IgG class were used. All results were presented as mean fluorescence intensity (MFI) values. Monitoring of complement activation on days 30, 60, and 100 post-transplant was started after completing epidemiological data in the first 10 pairs. All patients were checked for TA-TMA and GvHD development during routine post-transplant visits. TA-TMA screening included TA-TMA triad: hypertension or kidney injury, LDH increase and decrease in number of platelets or refractoriness to transfusions, and additionally decrease in hemoglobin concentration, proteinuria, and clinical presentation with TA-TMA involved organ damage. Schistocytes as non-objective and nonrepeatable markers were excluded from diagnostic criteria. Results Anti-HLA antibodies were detected in 9/20 (45%) of recipients, and in 9/20 (45%) of the donors despite the lack of any transfusion history in donor group. Neither the presence of DSA nor RSA was affected by gender. RSAs were present more often in donors (7/9; 77%) than DSAs in recipients (2/9; 22%); p=0.052. Data summarizing MFI values and type of antibodies are presented in table 1. Laboratory diagnosis of TA-TMA met 12/20 (60%) patients, with a significant clinical presentation including severe hypertension (3) pericarditis (1), gastrointestinal (5), or neurological (6) impairment in 8/12 (66%). All patients with RSA (7/7; 100%) developed TA-TMA compared to no-RSA group (5/13; 38%) (p<0.01). TA-TMA-mediated organ damage was noticed more often in the RSA population (5/7; 71%) compared to the no-RSA group (3/13, 23%) (p<0.01); (Table 2). A trend for higher activation of CH50 and MAC in RSA compared to a no-RSA group was noted with a mean CH50 93 vs. 82 (p=0,16), and MAC 1428 vs. 1007 (p=0,24) respectively. A trend for higher maximum concentrations of tacrolimus 14 vs 10.7 (p=0.07) was observed in patients with TA-TMA. There was no impact of ABO incompatibility on TA-TMA development. During the time of observation 6 patients (30%) developed aGvHD - grades I, II, and III were diagnosed in 3, 1, and 2 patients respectively. Only 1 patient with RSA developed aGvHD. There was no correlation between RSA and GvHD occurrence (RSA 1/7, no-RSA 5/13, p=0.26) and between aGvHD and TA-TMA. CMV reactivation was documented in 13/20 (65%) patients, with no differences between the RSA and no-RSA groups (p=0.65). Conclusions RSAs occur surprisingly often in the donor population, irrespectively to the donor`s gender and the lack of transfusions history. The exact role of these antibodies is not fully understood; however, our data may suggest their impact on complement activation and TA-TMA induction. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Investigating ITP Plasma for Effect on Platelet Production Using the Autologous Peripheral Blood Based Megakaryopoiesis Assay

Investigating ITP plasma for effect on platelet production using the autologous peripheral blood based megakaryopoiesis assay Nikola Ivetic, Ishac Nazy, Rumi Claire, Angela Huynh John G. Kelton, Donald M. Arnold. Background: Studies focused on megakaryocyte number and function are needed to understand platelet underproduction as a potential mechanism of immune thrombocytopenia (ITP). Most experimental studies have relied on animal models, specialized cell lines, or exogenous and non-autologous sources of hematopoietic stem and progenitor cells (HSPCs) as a source of megakaryocytic cells and platelet production. We used HSPCs isolated from ITP patients themselves to examine the effects their plasma has megakaryocyte growth and platelet production. Study Design and Methods: Megakaryocytes were produced from peripheral blood CD34+ HSCs directly from patients with ITP and healthy controls. HSPC (CD45+ CD34+) were isolated, expanded for 4 days and then cultured with thrombopoietin (TPO) and stem cell factor (SCF) for 8 days. Megakaryocyte numbers were evaluated by flow cytometry using CD41a expression for megakaryopoiesis and CD42b expression for maturation. Platelet production was analyzed using CD41a expression and platelet forward and side scatter profile sizes. The addition of autologous ITP plasma and plasma depleted of IgG were also tested to determine the effects of antibodies on megakaryopoiesis and thrombopoiesis. Results: Peripheral blood derived megakaryocytes were cultured from HSPCs from ITP patients (N=10), and normal controls (N=9). Approximately 2,200±1,100 hematopoietic stem and progenitor cells were isolated per ml of peripheral blood and a 5-fold increase in stem cells was obtained after an expansion of the isolated ITP patient HSPC population. Following an additional 8 days of culture with TPO, 67±12% of the cultured cells were CD41a+ indicating they were undergoing megakaryopoiesis and 54±15% of the CD41a+ population expressed the CD42b marker for mature megakaryocytes. Of the 10 ITP cultures grown, four grew significantly more mature megakaryocytes in comparison to healthy controls. The addition of ITP plasma did not inhibit megakaryocyte growth or maturity, but platelet production was reduced with two samples demonstrating a 50% reduction in platelet levels in comparison to the . Relative to the number of mature megakaryocytes cultured there was a lower number of platelets detected in ITP cultures (3.34±1.9 platelets per mature megakaryocyte) in comparison to the healthy control group (8.1±1.4 platelets per mature megakaryocyte). Conclusions: The addition of patient plasma had no inhibiting effect on megakaryocyte counts in an autologous assay but a significant decrease in platelet number (thrombopoiesis) was detected. A subset of ITP HSPC generated more megakaryocytes when compared to healthy donors, indicating these cells are generating more megakaryocytes. This is to our knowledge the first autologous investigation of ITP plasma on patient HSPC undergoing megakaryopoiesis.

Efficacy, tolerability and safety study of zinc hyaluronan for dogs with osteoarthritis

Relevance. In recent years, the problems of arthrology have become more relevant among domestic and farm animals. The significance of the article is due to the fact that in the Russian market of veterinary drugs, there is obviously a small number of drugs for the treatment of various pathologies of the joints, created on the basis of hyaluronic acid.Methods. 32 dogs of different sexes and breeds aged from 8 to 13 years with destructive-degenerative pathologies of the joints were selected for the study. Animals were treated with hyaluronic acid with zinc. Research methods: hematological analysis, general clinical examination.Results. In the process of drug therapy, in 81.25% of dogs was noted an increase in motor activity. Also, 7 days after the 5th injection of the drug, there was a significant decrease in the manifestations of starting pains up to their complete absence. The main positive changes in the course of arthrosis in dogs, according to all evaluation criteria, reached their maximum manifestation after 3–4th injections and remained practically unchanged by the 5th injection. The results of a biochemical study of blood serum indicate that against the background of the use of the drug in dogs with osteoarthritis, no significant changes were found that characterize the main types of metabolism. According to the results of hematological studies, it can be noted that in dogs receiving therapy with hyaluronic acid with zinc, there is a steady positive trend in a number of hematological parameters. So, a week after the 5th injection of the “Drug” there was a decrease in the total number of platelets. The percentage of eosinophils in the leukocyte formula stabilized to the upper values of the reference range. It is appropriate to emphasize that the “Drug” does not exhibit the properties of an antigen, and has a pronounced anti-inflammatory effect.

Immune Thrombocytopenic Purpura as a Hemorrhagic Versus Thrombotic Disease: An Updated Insight into Pathophysiological Mechanisms.

Immune thrombocytopenic purpura (ITP) is a blood disorder characterized by a low platelet count of (less than 100 × 109/L). ITP is an organ-specific autoimmune disease in which the platelets and their precursors become targets of a dysfunctional immune system. This interaction leads to a decrease in platelet number and, subsequently, to a bleeding disorder that can become clinically significant with hemorrhages in skin, on the mucous membrane, or even intracranial hemorrhagic events. If ITP was initially considered a hemorrhagic disease, more recent studies suggest that ITP has an increased risk of thrombosis. In this review, we provide current insights into the primary ITP physiopathology and their consequences, with special consideration on hemorrhagic and thrombotic events. The autoimmune response in ITP involves both the innate and adaptive immune systems, comprising both humoral and cell-mediated immune responses. Thrombosis in ITP is related to the pathophysiology of the disease (young hyperactive platelets, platelets microparticles, rebalanced hemostasis, complement activation, endothelial activation, antiphospholipid antibodies, and inhibition of natural anticoagulants), ITP treatment, and other comorbidities that altogether contribute to the occurrence of thrombosis. Physicians need to be vigilant in the early diagnosis of thrombotic events and then institute proper treatment (antiaggregant, anticoagulant) along with ITP-targeted therapy. In this review, we provide current insights into the primary ITP physiopathology and their consequences, with special consideration on hemorrhagic and thrombotic events. The accumulated evidence has identified multiple pathophysiological mechanisms with specific genetic predispositions, particularly associated with environmental conditions.

Effect of Combination of Traditional Chinese Medicine with Western Medicine on Endometrial Carcinoma and Its Influence on Ultrasound, MRI, Tumor Markers HE4 and CA125.

Objective To study the clinical efficacy of integrated traditional Chinese medicine (TCM) and Western medicine (WM) in treating endometrial cancer and the influence on ultrasound, magnetic resonance imaging (MRI), tumor markers, human epididymis protein 4 (HE4) and carbohydrate antigen 125 (CA125). Method A total of 152 cases of patients with endometrial carcinoma were randomly divided into two groups: the TCM + WM group and the WM group. The WM group was treated with megestrol acetate tablets, and the TCM + WM group was treated with Radix Astragali injection on the basis of the control group. The levels of inflammatory factors, HE4 and CA125 in serum, were detected using enzyme-linked immunosorbent assay (ELISA) or radioimmunoassay. The characteristics of ultrasound images and MRI images were observed and recorded. Toxicity, side effects, and the 3-year cumulative survival rate after treatment were assessed. Results After treatment, the levels of interleukin-4 (IL-4), tumor necrosis factor-alpha (TNF-α), and high-sensitivity C-reactive protein (hs-CRP) in both groups decreased, and the decrease in the TCM + WM group was more obvious than that in the WM group. There were statistically significant differences between the two groups in lesion shape, boundary, blood flow signal, lesion diameter, resistance index (RI), echo, intima thickness, and muscle layer infiltration from transvaginal ultrasound images after treatment. The diameter, echo, boundary, shape, composition, and enhancement degree of lesions between the two groups have a significant difference. Moreover, the levels of serum HE4 and CA125 in both groups decreased after treatment, and the decrease in the TCM + WM group was more obvious than that in the WM group. There were statistically significant differences between the two groups in the occurrence of myelosuppression, abnormal liver function, decreased platelet number, gastrointestinal reactions, leukopenia, and cardiotoxicity. After three years of follow-up, the cumulative survival rate of the TCM + WM group was 76.32%, and the cumulative survival rate of the WM group was 57.89%. Conclusion Radix Astragali injection combined with megestrol acetate tablets has obvious therapeutic effects against endometrial cancer. Through vaginal ultrasonography and MRI, it can significantly improve the size, shape, and blood flow signals of patients' lesions, reduce the level of serum inflammatory factors and tumor markers HE4 and CA125, reduce the incidence of toxic and side reactions, improve the patient's immunity, improve the patient's condition significantly, and prolong the survival time of patients.

The Association Between Weight Loss and Platelet Markers in Morbidly Obese Patients

Objective: To examine the association of weight loss achieved through obesity treatment with platelet number and markers (mean platelet volume, MPV; plateletcrit, PCT; platelet/lymphocyte ratio, PLR; and platelet distribution width, PDW) in morbidly obese patients.&#x0D; Methods: A total of 300 patients diagnosed with morbid obesity between 2017 and 2019 were included in this retrospective study. Weight at baseline and 6 months, body mass index (BMI), complete blood count (platelet, lymphocyte, plateletcrit, platelet/lymphocyte ratio, and platelet distribution width), and demographic data were evaluated.&#x0D; Results: A total of 300 morbidly obese patients with a BMI ≥ 40 kg/m2 were included. A weight loss of ≥ 10% was considered “significant”, and a weight loss of &lt; 10% was considered insignificant. A significant decrease in platelet number was found in association with weight loss (p &lt; 0.05), as were the changes in PCT and PLR. These findings suggest that platelet markers PCT and PLR may be associated with the degree of weight loss.&#x0D; Conclusion: Our results suggest that platelet markers simply obtained through a complete blood count may be utilized in the treatment and follow-up of obesity, which may lead to a number of different conditions such as coronary artery disease, cerebrovascular events, and myocardial infarction through predisposition to thrombosis.

Gene analysis and clinical features of MYH9-related disease

Objective: To identify gene variants and investigate clinical features of nonmuscle myosin heavy chain 9-related disease (MYH9-RD). Methods: In this retrospective study, the data of patients with MYH9-RD admitted to Shenzhen Children's Hospital from July 2017 to September 2020 were extracted. The gene variants, clinical features and laboratory tests results were summarized. Results: Among the 6 children, 4 were males and 2 were females, aged 4.0 (0.5-7.6) years. Main clinical manifestations included thrombocytopenia (6 cases), epistaxis (3 cases), petechias (2 cases), traumatic hematoma (1 case), and abnormal liver enzymes (1 case). One patient had no family history, and the other 5 cases were pedigrees. Two pedigrees (2 cases) had long-term microscopic hematuria, one pedigree (2 cases) had history of early cataract, and three pedigrees (5 cases) had chronic mild elevation of liver enzymes. Four MYH9 gene variants were found in 12 patients, including c.2104C>T(p.R702C) in exon 17, c.4270G>A(p.D1424N) in exon 31, c.5521G>A (p.E1841K) in exon 39, and c.5797C>T (p.R1933X) in exon 41. According to the family pedigrees analysis, except for the case of variant in exon 17 which was spontaneous mutation with no family history, the other variants were from their father or mother. The complete blood count results showed a decreased platelet number in these patients, and the counting results of the automated hematology analyzer were significantly lower than that of manual counting method ((33.4±17.2) × 10⁹ vs. (60.4±21.0) × 109/L,t=-5.83, P<0.05). The examination of the peripheral blood smear revealed the presence of thrombocytopenia with giant platelets and granulocyte inclusion bodies. The MYH9 gene variant (R702C) located at the N-terminus head domain of non-muscle myosin heavy chain ⅡA (NMMHC-ⅡA), which has ATPase activity, led to severe reduction of platelet number (<20×109/L) and obscure granulocyte inclusion bodies. However, higher platelet numbers (40×109-80×109/L) and obvious granulocyte inclusion bodies were observed in patients with tail-position mutations at C-terminus. Conclusions: The clinical phenotypes of MYH9-RD were variable. The mutations in certain regions of MYH9 gene were related to platelet count and granulocyte inclusion bodies. MYH9-RD should be considered in individuals with unknown etiology and persistent thrombocytopenia which is non-responsive to conventional treatment, regardless of family history. Complete blood count and blood smear morphology examinations are the first steps to screen and diagnose the disease. The laboratory should pay attention to the morphological review rules and standardized reports.

HEMOSTASTATIC ALTERATIONS WITH DISEASE SEVERITY IN THE EARLY SYMPTOMATIC PHASE OF COVID-19

IntroductionThe main factors associated with disease severity in Covid-19 are age, sex, body weight, hypertension, and diabetes. Biomarkers of hemostatic activation have been shown to be independent predictors of disease severity in different populations.AimTo evaluate whether biomarkers of hemostatic activation were associated with clinical outcomes in patients admitted to a field hospital set up to provide initial care to patients in the early symptomatic phase of Covid-19.MethodsData and samples were obtained from June to September 2020. Laboratory evaluation included complete blood counts, PT, aPTT, fibrinogen, D-dimer, factor VIII activity, Von Willebrand Factor (VWF) (activity and antigen), C reactive protein (CRP) and P-selectin (ELISA). Patients were segregated by outcome, with clinical worsening defined as need for ICU, mechanical ventilation, pulmonary embolism, deep vein thrombosis or death.Results and discussionIn total 209 were enrolled in the study, of which 24 presented clinical deterioration (11.5%). In both groups there was more male patients. In the group of clinical worsening the mean age was 58.1 and improvement was 53.6 years old. Concerning smoking, 3.2% of patients that improved smoke. Regarding pulmonar infiltrate, it was verified in 50% in the group that worsening versus 41% in clinical improvement. No differences could be observed between patient subgroups regarding the presence of fever (63.2% vs. 62.5%), dry cough (75.1% vs. 87.5%) and dyspnea (65.9% vs. 54.2%) at admission. As main comorbidities, the groups presented chronic obstructive pulmonary disease (2.2% vs 8.3%), asthma (3.2% vs 4.2%), chronic heart failure (1.1% vs 8.3%), arterial hypertension (46% vs 41.7%) and diabetes (28.1% vs 33.3%) in comparing improved with clinical deterioration patients. In general, it was verified a significant decrease in platelet number (p = 0.0426), and an increase in the parameters of aPTT (0.0084), CRP (p = 0.0450), vWF antigen (p = 0.0022) and ristocetin cofactor (p = 0.0032).ConclusionOur results demonstrate that hemostasis activation is associated with clinical deterioration even at the early phases of Covid-19. The Ethics Research Committee of the University of Campinas approved all of the experimental procedures, and all individuals signed the informed consent form.

Association and Correlation of Different Chemotherapy Regimens and Doses with Incidence and Severity of Thrombocytopenia among Solid Cancer Patients

Background: Thrombocytopenia is an abnormal decrease in platelet numbers and is a major detrimental side effect of chemotherapy or of cancer itself. Thrombocytopenia can lead to hemorrhage in vital organs, which is particularly a problematic specifically in solid cancer patients, and has a substantial negative effect on cancer patients’ quality of life (QOL). Thrombocytopenia ranges from mild bleeding from small blood vessels to severe bleeding from large blood vessels. Objectives: The present study aimed to describe the effect of chemotherapy regimens and doses on thrombocytopenia incidence and severity among solid cancer patients with thrombocytopenia. Materials and Methods: This retrospective observational study was conducted in Penang Hospital, a government hospital on Penang island, and included 341 cancer patients with thrombocytopenia who were admitted between 2003 and 2009. The main statistical tests used were the Chi-square test and logistic regression. The level of significance was set at P &lt; 0.05. Results: Of the 341 patients included, 21 (6.2%) had thrombocytopenia before chemotherapy and the remaining 320 (93.8%) developed it after chemotherapy. The majority of patients had moderate thrombocytopenia (n=172; 53.8%), followed by mild (n=97; 30.3%), and severe thrombocytopenia (n=51; 15.9%). FEC, 5-FU+5-FU, Docetaxel and Cisplatin regimen had strong associations and correlation with thrombocytopenia incidence and severity, but the associations and correlations for thrombocytopenia severity were stronger than those for incidence. The dosage of 5-FU, cyclophosphamide, docetaxel and cisplatin plays a critical role in thrombocytopenia incidence and severity. Conclusion: Monitoring and determination of hemoglobin levels for cancer patients treated with FEC, 5-FU+5-FU, Docetaxel, and Cisplatin specifically with high doses must be emphasized and a focus of particular attention.