Fragmented Erythrocytes Research Articles

The influence of heavy metals on cytotoxicity in Tilapia zillii

The present study was designed to investigate the cytotoxic effects and bioaccumulation of heavy metals iron (Fe), zinc (Zn), copper (Cu), cadmium (Cd), lead (Pb), manganese (Mn), nickel (Ni), and chromium (Cr) in different parts (muscle, gills, and liver) of Tilapia zillii occurring in polluted drainage canal and fish farm, which is located in Abiece region in front of village number 10, Alexandria governorate, Egypt. Results of water analysis revealed the concentration of Cd, Pb, Mn, Ni, and Cr exceeded the limits defined by the American Public Health Association (APHA) in the polluted drainage canal. In addition, the concentration of Ni elevated to the standard limits of APHA and Cu was not detected in the fish farm. Different types of chromosomal aberrations were recorded (e.g., stickiness, fragmented chromosomes, centromeric gaps, chromatid break, chromatid deletion, and tetraploid). Micronucleus frequency was found to be 5.58 in the polluted drainage canal group and 0.32 in the fish farm group. Other nuclear abnormalities such as blebbed nucleus, segmented nucleus, enucleated erythrocyte, kidney-shaped nucleus, heart-shaped nucleus, polymorphic irregular nuclei, binucleated cell, nuclear fragmented erythrocyte, long nucleus, putative fragmented notched nucleus, lobed nuclei, fused erythrocytes, necrotic erythrocyte, and vacuolated nucleus were recorded. The total of erythrocytes nuclear morphological abnormalities was 70.33% in the polluted drainage canal and 1.78% in the fish farm.

Dissociation Phenomenon of Erythrocyte Agglutination and Its Application to Assay of Functional Activity of the Complement System in Clinical Laboratory.

The objective of the study was to validate the dissociation phenomenon of erythrocyte agglutination which is based on erythrocyte fragments and to apply it in the functional activity assay of the complement system. The dissociation-agglutination effect of erythrocyte fragments was validated by detecting the number of free erythrocytes after the action of erythrocyte fragments on agglutinated erythrocytes. The number of free erythrocytes produced after hemolysis of agglutinated erythrocytes caused by complements and complement activators(CAs) was detected by auto hematology analyzer and the results were indicated by mean hemoglobin concentration of erythrocytes (MCHC). We optimized the test conditions and validated the inter-batch stability, explored the resolution of the assay method, and assayed for the total complement activity (AC) and the CAs activated complement activity (ACA) in serum from patients and healthy individual groups. Erythrocyte fragments have a dissociative effect on agglutinated erythrocytes. The auto hematology analyzer was able to detect AC and ACA, where AC showed an inverse correlation with MCHC, and ACA demonstrated a positive correlation with MCHC. The inter-batch CV of AC, ACA, and ACA/AC was found to be 5%, 9%, and 11.7%, respectively, with good stability. The study found that serum samples from acute phase reaction patients showed significant differences in ACA compared with healthy individuals, with a p value of 0.018; serum samples from patients with nephrotic syndrome showed significant differences in AC, ACA, and ACA/AC compared with healthy individuals, with p values of 0.014, 0.002, and 0.041, respectively. Erythrocyte fragments have dissociation-agglutination effect. The complement system immunological functional detection method, based on this effect, has potential clinical application value due to its sensitivity and accuracy.

Potential modifications of the PLASMIC scoring system for predicting thrombotic thrombocytopenic purpura: Sometimes, less is more.

Thrombotic thrombocytopenic purpura (TTP) is a life-threatening occlusive disease of the microcirculation characterized by systemic platelet plugs, organ ischemia, deep thrombocytopenia, and fragmentation of erythrocytes. One of the widely used scoring system to determine the clinical probability of TTP is the PLASMIC scoring system. This study aimed to evaluate the contribution of PLASMIC score modifications to sensitivity and specificity in patients with microangiopathic hemolytic anemia (MAHA) undergoing plasma exchange with a prediagnosis of TTP at our center. The data of patients who were hospitalized with a previous diagnosis of MAHA and TTP and underwent plasma exchange at Bursa Uludag University, Faculty of Medicine, Department of Hematology between January 2000 and January 2022 were retrospectively analyzed. Overall, 33 patients (including 15 and 18 with and without TTP, respectively) were included in this study. Receiver operating characteristic (ROC) analysis revealed that the area under the curve (AUC) for the original PLASMIC score was 0.985 (95% confidence interval [95% CI]: 0.955-1.000), and AUC for the PLASMIC score without mean corpuscular volume (MCV) was 0.967 (95% CI: 0.910-1.000), which is close to the original AUC. With the removal of MCV from the scoring system, the sensitivity decreased from 100% to 93%, whereas the specificity increased from 33% to 78%. Based on the results of this validation study, removing MCV from the PLASMIC score led to the categorization of eight non-TTP cases in the low-risk category, and this could avoid unnecessary plasma exchange. However, in our study increasing the specificity was at the expense of the sensitivity by missing one patient with this new scoring system without MCV. Further multicenter studies with large sample sizes are required owing to the fact that different parameters may be effective in TTP prediction among different populations.

STUDY OF RED CELL DISTRIBUTION WIDTH AS A NOVEL PREDICTIVE INDICATOR IN PREHYPERTENSIVE AND HYPERTENSIVE PATIENTS

Background: An increased RDW mirrors a profound deregulation of erythrocyte homeostasis involving both impaired erythropoiesis and abnormal red blood cell survival, which may be attributed to a variety of underlying metabolic abnormalities such as shortening of telomere length, oxidative stress, inflammation, poor nutritional status, dyslipidaemia, hypertension, erythrocyte fragmentation and alteration of erythropoietin function. High blood pressure does damage to endothelial cells that leads to the secretion of inflammatory cytokines which supresses erythropoiesis and inhibit red cell maturation and anisocytosis. Therefore, as a sensitive marker of inflammatory status in this process, RDW can be a potential predictor of hypertension in pre-hypertensive and normal individual. To provi Aim: de general information about RDW and its routine assessment, to review the most relevant implications in prehypertensive and hypertensive patients and give some insights about its potential clinical applications. Current Material and methods: study was observational cross sectional study conducted at the Department of Medicine in SHRI RAJENDRA GENERAL HOSPITAL (SRGH), Jhalawar Medical College, Jhalawar Rajasthan. A total 100 newly diagnosed hypertensive and pre hypertensive patients were included in the study. Data were analysed in SPSS 21. Independent t-test and Chi-square test were applied. P value <0.05 was considered statistically significant. In this study, mean age of st Results: udy participants was 46.4±19.1 years and out of the 100 participants, maximum 40 were belongs to age <40 years followed by 37 in age of 41-60 years, 47 were male and 53 were female, 75 participants were diagnosed as hypertensive and 25 diagnosed as prehypertensive. In this study, mean RDW-CV and RDW-SD was 19.2±3.8 and 54.8±10.7 respectively and a statistically significant high RDW-CV and RDW-SD was found among hypertensive compare to pre-hypertensive patients. Also a statistically significant positive correlation of SBP and DBP was found with RDW-CV and RDW-SD. Conclusion: Our study concluded that RDW is significantly positively correlated with the blood pressure and increases as SBP and DBP increases. So RDW can be predictive marker for hypertension. This can be done routinely and easily in the laboratories, thereby giving the clinician a good supportive tool for diagnosing and preventing an adverse outcome.

Thrombotische Mikroangiopathien

In the emergency room, patients with anemia and thrombocytopenia are common. Although these findings can often be explained by the medical situation, thrombotic microangiopathy is an important differential diagnosis. In this case, occlusion of the smallest vessels consequently leads to functional impairment of the affected organs. Patients generally present with symptoms of organ dysfunction, e.g., in the kidney or brain. Characteristically, Coombs-negative fragmentation of erythrocytes with hemolysis occurs in the area of the occluded vessels. Lactate dehydrogenase levels are elevated, and platelets and haptoglobin are reduced. Differential diagnoses beyond thrombotic microangiopathy that should be considered are numerous and diverse in their pathophysiology. Rapid workup is needed, because sometimes aspecific treatment must be initiated rapidly. For example, thrombotic thrombocytopenic purpura leads to death in about 90% of patients if left untreated. However, by reconstitution of the underlying deficiency of the so-called ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) by plasma separation, survival can be ensured in most cases. Complement-mediated hemolytic uremic syndrome should also be considered and, if suspected, treated with complement inhibition. In many cases, however, thrombotic microangiopathy reflects adisorder elsewhere and may be amanifestation of severe hypertension or acoagulation disorder, such as disseminated intravascular coagulation or antiphospholipid syndrome. It can also be observed as aconsequence of drug therapies or metabolic derangement. Systemic workup is therefore necessary for rapid clarification of differential diagnoses.

Ultrastructural evidence of four types of lipofuscins in the melanomacrophagic centers in hepatocytes of zebrafish (Denio rerio)

Melanomacrophagic centers (MMCs) were studied in the hepatocytes of zebrafish using transmission electron microscope (TEM). The MMCs with irregular or amoeboid nucleus were located in the hepatocytes adjacent to the bile canaliculi. Several engulfed structures were present in the cytoplasm of MMCs. The most frequent observation was the presence of mitochondria, ranging in size from small to giant, with distorted shape and inconspicuous cristae. Occasionally the fragments of erythrocytes were found. The rough endoplasmic reticulum (rER) showed whirling around the mitochondria and lipid droplets, forming membrane-like structures. The damaged mitochondria were invaded by the lysosomes, and this was covered by a membrane led to the formation of lipofuscin. Four different types of lipofuscins were observed; namely, (1) granular with/without vacuoles of high electron-density, (2) homogenous surrounded by indistinct limiting membrane, (3) lamellated structures similar to inner matrix and cristae of mitochondria, and, (4) compound structure made by the combinations of first 3 types, (granular and homogenous, granular and lamellated, homogenous and lamellated). The present evidence suggests that MMCs in the hepatocytes of zebrafish perform continuous functions of removal of the damaged cellular organelles. The lipofuscin formation work in coordination with the cellular players of immune system and remove pathogens and maintain the internal homeostasis of cells.

A Novel and Less Traumatic Needle for Kidney Puncture: Development and Preclinical Study Results.

Abstract Introduction: A considerable proportion of percutaneous nephrolithotomy complications occurs during renal puncture. An option to decrease the complications rate is needle modification to make the procedure less traumatic. We aimed to evaluate the effectiveness of the novel MG needle in a preclinical study. Materials and Methods: We developed an original MG needle based on the Veress needle concept containing an atraumatic (blunt) mandrin connected through a spring to the cannula. The MG needle's properties were compared with those of the conventional Chiba and Trocar needles in two experiments. In the first experiment, we assessed the force required to puncture the model. In the second experiment, we punctured a porcine kidney and analyzed histology report after the puncture. Results: We performed a series of 30 punctures of polypropylene block by each needle. The force required to make a puncture with the Chiba needle (6.53 ± 0.87 N) was significantly lower compared with the MG needle (7.1 ± 1.07 N), p = 0.027. However, the MG needle turned out to be superior to the Trocar needle (8.71 ± 1.08 N), p = 0.001. A total of 15 specimens were obtained after three renal punctures were made with each needle. A microscopy of the specimen after puncture with the Chiba and Trocar needles showed small fragments of epithelium and erythrocytes inside the canal with uneven margins where the needle passed. A microscopy of the specimen after puncture with a novel MG needle showed a canal with even margins. No tissue fragments inside the canal were observed. Conclusion: The force required to puncture with the novel MG needle is comparable with conventional needles. According to preclinical experiments, histology report of porcine kidney indicates that renal puncture with an MG needle is less traumatic. It may reduce the risk of bleeding, and this should be proved during clinical trials.

Coronavirus disease 2019 (COVID-19): Focus on peripheral blood cell morphology.

Numerous studies have shown peculiar morphological anomalies in COVID-19 patients' smears. We searched all the peer-reviewed scientific publications that explicitly reference the cytomorphological alterations on peripheral blood smears of patients with COVID-19. We extracted data from sixty-five publications (case reports, patient group studies, reviews, and erythrocyte morphology studies). The results show that frequent alterations concern the morphology of lymphocytes (large lymphocytes with weakly basophilic cytoplasm, plasmacytoid lymphocytes, large granular lymphocytes). Neutrophils display abnormal nuclei and cytoplasm in a distinctive cytomorphological picture. Besides a left shift in maturation, granulations can be increased (toxic type) or decreased with areas of basophilia. Nuclei are often hyposegmented (pseudo-Pelger-Huёt anomaly). Apoptotic or pycnotic cells are not uncommon. Monocytes typically have a large cytoplasm loaded with heterogeneous and coalescing vacuoles. Platelets show large and giant shapes. The presence of erythrocyte fragments and schistocytes is especially evident in the forms of COVID-19 that are associated with thrombotic microangiopathies. Such atypia of blood cells reflects the generalized activation in severe COVID-19, which has been demonstrated with immunophenotypic, molecular, genetic, and functional methods. Neutrophils, in particular, are involved in the pathophysiology of hyperinflammation with cytokine storm, which characterizes the most unfavorable evolution.

342.3: Outcome Analysis of Patients With Genetic Mutations of Complement Regulatory Proteins in Relation to Incidence of Post Renal Transplant Thrombotic Microangiopathy

Introduction: Thrombotic Microangiopathy is an occlusive disorder of microvasculature characterized by thrombocytopenia, systemic or intrarenal platelet aggregation, thrombus formation and hemolytic anemia caused by fragmentation of erythrocytes due to the disturbed microvasculature. TMA developing after renal transplantation can be categorized into either De novo TMA, developing for the first time without any evidence of the disease before the transplant or recurrent TMA where native kidneys have failed due to TMA and recur after kidney transplantation. The contribution of complement regulatory gene (CRG) mutation to post-transplant Thrombotic Microangiopathy (TMA) in Indian kidney transplant recipients (KTR) is unknown. This is a study to determine the association of CRG on post-transplant TMA and graft failure. Methods: A Single Centre, Prospective Observational Cohort Study was undertaken in renal transplant recipients. All live and Deceased donor renal allograft recipients who underwent transplantation from 1st December 2019 onwards till 31st December 2020 were recruited and were followed up for 1 year beyond the last enrolment. Genetic testing was performed with MLPA and Clinical exome sequencing. Results: 78 KTRs with a mean age of 37.09 ± 13.23 years were enrolled. The Native cause of kidney disease in 55 (70.5%) patients was undetermined and 23 (29.5%) had established cause of chronic kidney disease. 58 (74.4%) were males and 20 (25.6%) were females. CRG mutation was seen in 48/78 (61.5%) KTRs. The allele frequency of the CRG mutation was seen in 48/78 (61.53%) of which duplication of CFHR gene was predominantly seen in 40/78 (51.2%) patients. CRG mutation in this cohort was seen more in the younger age group patients. There was no gender predominance for patients with CRG mutation. None of the patients had a mutation for CFH, CFI, CFB, C3, THBD, DGKE genes. One patient had a mutation for the PLG gene. The incidence of post-transplant TMA was seen in 4/78 (5.12%) patients. Mutation related to aHUS was seen in 2 patients. There was no significant difference in serum creatinine levels of patients with or without CRG mutation at the end of 1 year. Conclusion: The prevalence of CRG mutation in our KTR cohort was high and is associated with post-transplant TMA in 50% of patients with de novo TMA. The graft outcome at the end of 1 year was similar in patients with mutation and those without mutation. This study suggests that the presence of CRG mutation should not preclude renal transplantation in patients with ESRD.

Human erythrocyte fragmentation during ex-vivo pig organ perfusion.

Platelet sequestration is a common process during organ reperfusion after transplantation. However, instead of lower platelet counts, when using traditional hemocytometers and light microscopy, we observed physiologically implausible platelet counts in the course of ex-vivo lung and liver xenograft organ perfusion studies. We employed conventional flow cytometry (FC) and imaging FC (AMINS ImageStream X) to investigate the findings and found platelet-sized fragments in the circulation that are mainly derived from red blood cell membranes. We speculate that this erythrocyte fragmentation contributes to anemia during in-vivo organ xenotransplant.

Erythrocyte interaction with neutrophil extracellular traps in coronary artery thrombosis following myocardial infarction.

Cardiovascular disease, including myocardial infarction (MI), is the leading cause of death globally. Current antithrombotic medications used during MI treatment are predominantly directed towards platelet inhibition and, to a lesser extent, anticoagulation. Bleeding is a major risk of such treatment and could be circumvented by targeting other causative factors essential for arterial thrombus formation. We sought to re-evaluate the cellular composition of arterial thrombus in order to better understand mechanisms that lead to coronary artery thrombosis in acute MI. We performed detailed histological and immunohistochemical analysis of coronary artery thrombi aspirated from 26 patients undergoing emergency percutaneous coronary intervention for acute ST elevated myocardial infarction (STEMI). Coronary arterial thrombi had an unanticipated cellular heterogeneity. Neutrophil extracellular traps (NETs) were observed in thrombi as identified by anti-citrullinated histone 3 and anti-myeloperoxidase staining. Increased abundance of NETs was seen directly surrounding erythrocytes. Extracellular iron and erythrocyte fragments were also associated with areas of NETs suggesting a possible link. Our results shed light on potential involvement of erythrocytes in coronary arterial thrombosis through activation of platelets and induction of NETs. If supported by further invitro and invivo studies, novel therapies to inhibit NET formation or coagulation activation by erythrocyte release products, could bolster current myocardial infarction treatment.

A Flow Cytometry-Based Assay for the Measurement of Total Complement Activity in the Serum and Clinical Practice.

Objective To develop a novel sensitive and accurate assay suitable for high-volume testing of the total complement activity in the serum for clinical laboratories. Methods The total complement activity (TCA) to be measured was quantified by detecting the number of fragments produced by erythrocyte lysis and the erythrocyte fragmentation index (EFI), indicating TCA. EFI = M × M2/(M1 + M2), where M is the number of erythrocyte fragments (removed from the background), M1 is the number of unagglutinated red cells, M2 is the number of agglutinated red cell groups, and M2/(M1 + M2) is the agglutination coefficient indicating the degree of erythrocyte agglutination. Mild changes in hemolysin and erythrocyte concentrations were made to optimize the testing conditions. The same serum samples were tested for 10 consecutive days to determine the stability of the experimental results. Serum EFI was detected in both nephrotic syndrome patients and healthy subjects. Results There was a linear relationship between hemolysin and erythrocyte agglutination (r = 0.999, P < 0.001). A good linear relationship existed between EFI and TCA (r = 0.991, P < 0.001). The results were not affected by slight fluctuations in the concentrations of hemolysin or erythrocytes. The interbatch CV = 8.6% of the test results showed good stability. There was a significant difference in the EFI between nephrotic syndrome patients and healthy individuals, P < 0.001, and EFI was reduced in nephrotic syndrome patients compared to healthy individuals. Conclusion The flow cytometry-based assay for TCA was sensitive and accurate and had potential value for clinical application.

Childhood\u2010onset systemic lupus erythematosus with trisomy X and the increased risk for bone complications: a case report

BackgroundSystemic lupus erythematosus is a multi-organ inflammatory autoimmune disease; immune complexes are part of the pathogenesis, but not entirely responsible. Trisomy X is the most common female chromosomal abnormality and the role of an additional X chromosome in the development of systemic lupus erythematosus is well recognized. However, the potential complications and optimal management of childhood lupus with trisomy X remain unclear. Herein, we describe a case of childhood-onset systemic lupus erythematosus associated with severe bone complications presumably secondary to trisomy X.Case presentationA 16-year-old Japanese girl was diagnosed with childhood-onset systemic lupus erythematosus and trisomy X. A chromosomal abnormality (47, XXX) was incidentally identified on bone marrow examination initially done to determine the cause of pancytopenia. She had a persistent headache, fever for six days, diffuse hair loss, mucosal ulcers, butterfly eruptions, and palmar erythema. Furthermore, thrombocytopenia, anemia, and erythrocyte fragmentation were detected, suggesting secondary thrombotic microangiopathy. She was initially treated with intravenous methylprednisolone pulse therapy and prescribed monthly cyclophosphamide for severe disease activity, prednisolone, mycophenolate mofetil, and hydroxychloroquine as remission maintenance drugs. She developed generalized extremity pain that had been worsening throughout the disease. Extremity magnetic resonance imaging performed 12 months after the treatment onset revealed multifocal avascular necrosis, and dual-energy X-ray absorptiometry revealed further decreased bone mineral density. High plasma levels of factor VIII were detected by additional tests for coagulation functions, and we suspected the possibility that factor VIII might cause avascular necrosis due to thrombosis. Currently, she is being treated with prednisolone and MMF for SLE. However, her extremity pain has not been managed effectively even under the administration of non-steroidal anti-inflammatory drugs and pregabalin.ConclusionsAn additional X chromosome has been reported to be associated with factor VIII and osteoporosis. Additionally, elevated plasma levels of FVIII is the risk factors for thrombosis, which leads to the risk of avascular necrosis. Patients with systemic lupus erythematosus complicated by trisomy X might be at a higher risk of avascular necrosis and osteoporosis that can also manifest in childhood systemic lupus erythematosus.

No Evidence for Classic Thrombotic Microangiopathy in COVID-19.

Background: Coronavirus disease-2019 (COVID-19) triggers systemic infection with involvement of the respiratory tract. There are some patients developing haemostatic abnormalities during their infection with a considerably increased risk of death. Materials and Methods: Patients (n = 85) with SARS-CoV-2 infection attending the University Medical Center, Mainz, from 3 March to 15 May 2020 were retrospectively included in this study. Data regarding demography, clinical features, treatment and laboratory parameters were analyzed. Twenty patients were excluded for assessment of disseminated intravascular coagulation (DIC) and thrombotic microangiopathy (TMA) due to lack of laboratory data. Results: COVID-19 patients (n = 65) were investigated, 19 with uncomplicated, 29 with complicated, and 17 with critical course; nine (13.8%) died. Seven patients showed overt DIC according to the ISTH criteria. The fibrinogen levels dropped significantly in these patients, although not below 100 mg/dl. Hallmarks of TMA, such as thrombocytopenia and microangiopathic haemolytic anaemia, were not detected in any of our COVID-19 patients. ADAMTS13 activity was mildly to moderately reduced in 4/22 patients, all having strongly elevated procalcitonin levels. Conclusion: DIC occurred in 7/65 COVID-19 patients but fibrinogen and platelet consumption were compensated in almost all. ADAMTS13 assays excluded TTP and hallmarks of classic TMA were absent in all investigated patients. We hypothesize that the lacking erythrocyte fragmentation and only mild platelet consumption in severe COVID-19 are due to a microangiopathy predominantly localized to the alveolar microcirculation with a low blood pressure gradient.

Comparison of sample preparation methods, validation of an UPLC–MS/MS procedure for the quantification of cyclosporine A in whole blood sample

Current main methods for therapeutic drug monitoring (TDM) of cyclosporine A (CsA) are immunoassays and liquid chromatography tandem mass spectrometry. The sample pretreatment of these methods is mainly based on extraction of drug which is bound to erythrocytes by divalent heavy metal ions (such as zinc and copper). Although these methods are effective for whole blood drug extraction and measurement, the pollution of heavy metals in sample pretreatment process will have potential negative impact on environment and human health. To overcome the pollution problem, in this study we have developed and validated an UPLC-MS/MS method for CsA determination in whole blood samples using physical pretreatment method. According to the characteristics of erythrocytes, a series of physical pretreatment methods, including sonication, freeze-thaw and osmotic burst, have been developed and evaluated. The results showed that the osmotic burst method was an effective way for drug extraction from erythrocytes. The lower limit of quantitation for CsA was 25 ng/mL, the within-run and between-run coefficient of variations were both less than 11.6 %. The agreement of the UPLC-MS/MS methods using these two sample pretreatment was evaluated by Bland-Altman plot and the two-tailed Student’s T-test. Comparison studies show that the effect of erythrocyte fragmentation by osmotic burst is similar to that of zinc sulfate method. The CsA measurement of 103 whole blood samples obtained by these two UPLC-MS/MS assays were no significant difference. These results demonstrate that the sample pretreatment by osmotic burst method is an eco-friendly and precise method for detecting the whole blood CsA concentration and therapeutic drug monitoring of CsA.

Clinical analysis of 61 patients with thrombotic thrombocytopenic purpura

OBJECTIVE To analyze and summarize the clinical features, diagnosis, treatment and prognosis of 61 patients with thrombotic thrombocytopenic purpura (TTP), so as to improve the ability of diagnosis and treatment. METHODS The clinical data of 61 TTP patients admitted to Peking University People's Hospital from January 2004 to March 2019 were retrospectively analyzed, and the clinical manifestations, blood routine, hemolysis indicators, and von Willebrand factor lyase (von Willebrand factor-cleaving protease, vWF-CP, also known as ADAMTS13) of these patients were observed. According to the outcome at the time of discharge, they were divided into survival group and death group, and the differences in clinical characteristics, neutrophil to lymphocyte ratio (NLR) and plasma exchange between the two groups were compared. The PLASMIC scores were calculated and compared with ADAMTS13 to determine the accuracy of the PLASMIC score in predicting ADAMTS13. RESULTS Among the 61 TTP patients, 22 were males and 39 were females, with an average age of (48±17) years. In the study, 48 cases had pentalogy, only 9 had triad, and the remaining 4 had no neuropsychiatric symptoms. Twenty-seven cases (44.3%) died and 34 cases (55.7%) survived. Among the 61 TTP patients, the platelet count was (12.9±9.5)×109/L, the hemoglobin (66.5±20.7) g/L, the percentage of erythrocyte fragments 3% (2%, 7%), and the plasma free hemoglobin increased to 360 (200, 457) mg /L, and the lactate dehydrogenase 1 508 (811, 2 133.8) U/L. The blood clotting was basically normal. The ADAMTS13 value of 30 patients was 49.0 (40.8, 61.3) μg/L, the ADAMTS activity of 10 patients was 0.05). The total amount and frequency of plasma exchange (PEX) in the death group were significantly less than those in the survival group, and the difference was statistically significant (P 0.05). CONCLUSION PEX can significantly improve the survival rate of TTP patients. PLASMIC score can easily and quickly predict the possibility of ADAMTS13 activity reduction, which is beneficial to the early diagnosis of TTP and PEX treatment. NLR can reflect the systemic inflammatory process, but its significance in TTP needs further study.

Potential Use of Antifreeze DNA Aptamers for the Cryopreservation of Human Erythrocytes

This article summarizes proof of concept experiments which clearly demonstrated the ability of DNA aptamers selected against a molecular mimic of early ice crystal nuclei to protect the integrity of human erythrocytes following a slow freeze-thaw cycle. Following 10 cycles of selection and DNA amplification of rare candidate DNA aptamers against a copper-organic ligand complex which holds water molecules in a conformation resembling early ice crystal nuclei, the aptamers were tested for their ability to preserve erythrocyte morphology by phase-contrast microscopy versus controls without aptamers and with the original randomized aptamer DNA library template following slow freezing and storage overnight at -20 °C with slow thawing at 25 °C. Those experiments revealed that a minimum of 32 μg/ml of the final selected aptamer pool of DNA molecules was required to completely protect nearly 100% of the erythrocytes. By contrast, the treatment groups without the aptamers or with the randomized aptamer template DNA at 32 μg/ml produced only fragmented erythrocytes and cellular debris (no intact cells), thus indicating that specifically selected DNA conformations were required to bind and limit the size of forming ice crystals to cryoprotect the erythrocytes.

Renal Biopsy Prognostic Findings in Children With Atypical Hemolytic Uremic Syndrome.

The aim of this study was to investigate the histopathological findings in kidney biopsies in children with atypical hemolytic uremic syndrome (aHUS) and to determine whether specific pathological findings in aHUS have a prognostic value. Renal biopsy specimens of 29 patients who were recorded in the national Turkish aHUS registry database were available for review. Histopathological findings were compared with the clinical and laboratory features at the presentation and the final outcome. The mean age at presentation and follow-up period was 4.9 ± 3.9 and 3.9 ± 3.0 years, respectively. The median time interval from the first symptom to biopsy was 10 days. Vascular thrombosis and interstitial fibrosis were significantly related to chronic kidney disease (CKD) requiring dialysis or kidney transplantation during follow-up (5.6-fold, for both). Glomerular necrosis, cortical necrosis, and glomerular sclerosis were markedly associated with CKD without dialysis (6.2-fold, 13.3-fold, and 8.8-fold, respectively). However, presence of endothelial swelling, subendothelial widening, and fragmented erythrocytes was found to be correlated with a favorable final outcome. Presence of vascular thrombosis, cortical necrosis, and glomerular sclerosis in histopathological evaluation correlated with developing CKD. Chronic changes in the interstitial compartment were also related to poor prognosis, a finding that has been shown for the first time in pediatric aHUS cases.

Histone-induced thrombotic thrombocytopenic purpura in adamts13 -/- zebrafish depends on von Willebrand factor.

Thrombotic thrombocytopenic purpura (TTP) is caused by severe deficiency of ADAMTS13 (A13), a plasma metalloprotease that cleaves endothelium-derived von Willebrand factor (VWF). However, severe A13 deficiency alone is often not sufficient to cause an acute TTP; additional factors may be required to trigger the disease. Using CRISPR/Cas9, we created and characterized several novel zebrafish lines carrying a null mutation in a13−/−, vwf, and both. We further used these zebrafish lines to test the hypothesis that inflammation that results in neutrophil activation and release of histone/DNA complexes may trigger TTP. As shown, a13−/− zebrafish exhibit increased levels of plasma VWF antigen, multimer size, and ability of thrombocytes to adhere to a fibrillar collagen-coated surface under flow. The a13−/−zebrafish also show an increased rate of occlusive thrombus formation in the caudal venules after FeCl3 injury. More interestingly, a13−/− zebrafish exhibit ~30% reduction in the number of total, immature, and mature thrombocytes with increased fragmentation of erythrocytes. Administration of a lysine-rich histone results in more severe and persistent thrombocytopenia and a significantly increased mortality rate in a13−/−zebrafish than in wildtype (wt) ones. However, both spontaneous and histone-induced TTP in a13−/− zebrafish are rescued by the deletion of vwf. These results demonstrate a potentially mechanistic link between inflammation and the onset of TTP in light of severe A13 deficiency; the novel zebrafish models of TTP may help accelerate our understanding of pathogenic mechanisms and the discoveries of novel therapeutics for TTP and perhaps other arterial thrombotic disorders.

Synergistic effects of ADAMTS13 deficiency and complement activation in pathogenesis of thrombotic microangiopathy

AbstractSevere deficiency of plasma ADAMTS13 activity is the primary cause of thrombotic thrombocytopenic purpura (TTP) whereas overwhelming activation of complement via an alternative pathway results in atypical hemolytic uremic syndrome (aHUS), the prototypes of thrombotic microangiopathy (TMA). However, clinical and pathogenic distinctions between TTP and aHUS are often quite challenging. Clinical reports have suggested that complement activation may play a role in the development of TTP, which is caused by severe deficiency of plasma ADAMTS13 activity. However, the experimental evidence to support this hypothesis is still lacking. Here, we show that mice with either Adamts13−/− or a heterozygous mutation of complement factor H (cfh) at amino acid residue of 1206 (ie, cfhW/R) alone remain asymptomatic despite the presence of occasional microvascular thrombi in various organ tissues. However, mice carrying both Adamts13−/− and cfhW/R exhibit thrombocytopenia, low haptoglobin, increased fragmentation of erythrocytes in peripheral blood smear, increased plasma levels of lactate dehydrogenase activity, blood urea nitrogen, and creatinine, as well as an increased mortality rate, consistent with the development of TMA. Moreover, mice with a homozygous mutation of cfh (ie, cfhR/R) with or without Adamts13−/− developed severe TMA. The mortality rate in mice with Adamts13−/−cfhR/R was significantly higher than that in mice with cfhR/R alone. Histological and immunohistochemical analyses demonstrated the presence of disseminated platelet-rich thrombi in terminal arterioles and capillaries of major organ tissues in these mice that were either euthanized or died. Together, our results support a synergistic effect of severe ADAMTS13 deficiency and complement activation in pathogenesis of TMA in mice.