Plasmodium falciparum utilizes pyrophosphate to fuel an essential proton pump in the ring stage and the transition to trophozoite stage.

During asexual growth and replication cycles inside red blood cells, the malaria parasite Plasmodium falciparum primarily relies on glycolysis for energy supply, as its single mitochondrion performs little or no oxidative phosphorylation. Post merozoite invasion of a host red blood cell, the ring stage lasts approximately 20 hours and was traditionally thought to be metabolically quiescent. However, recent studies have shown that the ring stage is active in several energy-costly processes, including gene transcription, protein translation, protein export, and movement inside the host cell. It has remained unclear whether a low glycolytic flux alone can meet the energy demand of the ring stage over a long period post invasion. Here, we demonstrate that the metabolic by-product pyrophosphate (PPi) is a critical energy source for the development of the ring stage and its transition to the trophozoite stage. During early phases of the asexual development, the parasite utilizes Plasmodium falciparum vacuolar pyrophosphatase 1 (PfVP1), an ancient pyrophosphate-driven proton pump, to export protons across the parasite plasma membrane. Conditional deletion of PfVP1 leads to a delayed ring stage that lasts nearly 48 hours and a complete blockage of the ring-to-trophozoite transition before the onset of parasite death. This developmental arrest can be partially rescued by an orthologous vacuolar pyrophosphatase from Arabidopsis thaliana, but not by the soluble pyrophosphatase from Saccharomyces cerevisiae, which lacks proton pumping activities. Since proton-pumping pyrophosphatases have been evolutionarily lost in human hosts, the essentiality of PfVP1 suggests its potential as an antimalarial drug target. A drug target of the ring stage is highly desired, as current antimalarials have limited efficacy against this stage.

Platelets play a dual role in the pathophysiology of transfusion-related acute lung injury.

Platelets are increasingly recognized as key regulators of inflammatory and immune responses, through their interaction with endothelium and immune cells. Therefore they might have a role in transfusion-related acute lung injury (TRALI), in which endothelial cells and neutrophils are the key players. In this study, by a classic TRALI animal model, combining a custom-designed system for intravital confocal microscopy of pulmonary microvasculature and a platelet tracking technique, we found that thrombin-activated platelets transfusion aggravated TRALI while resting platelets transfusion alleviated TRALI. Promoting endogenous platelets activation also aggravated TRALI while inhibiting endogenous platelets activation alleviated TRALI. Activated platelets interfered with the stability of endothelial barrier function while resting platelets modulated the activation of neutrophils. Anti-thrombin could alleviate TRALI, which was not reproduced upon anti-GPIIbIIIa or anti-P-selectin In conclusion, platelets might play a dual role (protective and pathogenic) in TRALI, the balance between the two roles is highly dependent on whether platelets are activated by thrombin or not. This might explain the conflicting results of previous researches studying the contribution of platelets in TRALI by platelet depletion technology, in which the induction of TRALI and the condition of animals were different, hence the state of platelets during TRALI was different. Moreover, anti-platelet-activation (such as anti-thrombin) might be a better approach than anti-activated-platelets (such as anti-P-selectin) to search for potential therapies in TRALI. Considering the involvement of thrombin-activated platelets in TRALI, anti-thrombin might be needed when blood component transfusion is performed.

Transcriptional changes in Plasmodium falciparum upon conditional knock down of mitochondrial ribosomal proteins RSM22 and L23.

The mitochondrion of malaria parasites is an attractive antimalarial drug target, which require mitoribosomes to translate genes encoded in the mitochondrial (mt) DNA. Plasmodium mitoribosomes are composed of highly fragmented ribosomal RNA (rRNA) encoded in the mtDNA. All mitoribosomal proteins (MRPs) and other assembly factors are encoded in the nuclear genome. Here, we have studied one putative assembly factor, RSM22 (Pf3D7_1027200) and one large subunit (LSU) MRP, L23 (Pf3D7_1239100) in Plasmodium falciparum. We show that both proteins localize to the mitochondrion. Conditional knock down (KD) of PfRSM22 or PfMRPL23 leads to reduced cytochrome bc1 complex activity and increased sensitivity to bc1 inhibitors such as atovaquone and ELQ-300. Using RNA sequencing as a tool, we reveal the transcriptomic changes of nuclear and mitochondrial genomes upon KD of these two proteins. In the early phase of KD, while most mt rRNAs and transcripts of putative MRPs were downregulated in the absence of PfRSM22, many mt rRNAs and several MRPs were upregulated after KD of PfMRPL23. The contrast effects in the early phase of KD likely suggests non-redundant roles of PfRSM22 and PfMRPL23 in the assembly of P. falciparum mitoribosomes. At the late time points of KD, loss of PfRSM22 and PfMRPL23 caused defects in many essential metabolic pathways and transcripts related to essential mitochondrial functions, leading to parasite death. In addition, we enlist mitochondrial proteins of unknown function that are likely novel Plasmodium MRPs based on their structural similarity to known MRPs as well as their expression profiles in KD parasites.

A Triple-Heterozygous ß-Thalassemia Patient Demonstrated an Unusual Electrophoresis Pattern Due to a Novel ß0 Mutation [an IVS-II-654 (C>T) mutation with a Hb Zürich-Langstrasse (HBB: c.151A>T) mutation in cis].

ß-Thalassemia (ß-thal) is caused by mutations on the ß-globin genes, causing reduced (ß+) or absent (ß0) synthesis of the ß chains of hemoglobin (Hb). In this report, a 28-year-old male patient with anemia and jaundice, was diagnosed with triple-heterozygous ß-thal [an IVS-II-654 (C>T) mutation, a Hb Zürich-Langstrasse (HBB: c.151A>T) mutation and a Hb G-Siriraj (HBB: c.22G>A) mutation] by gene sequencing. However, his electrophoresis pattern was unusual: 90.8% Hb G-Siriraj, 5.9% Hb A2, 3.3% Hb F, no Hb A, no Hb Zürich-Langstrasse. His mother carried a ß-thal trait (ßA/ßIVS-II-654) having mild anemia, with a classical electrophoresis pattern (95.1% Hb A, 4.4% Hb A2, 0.5% Hb F). His father was heterozygous for Hb G-Siriraj (ßA/ßG-Siriraj) but asymptomatic, with a corresponding electrophoresis pattern (63.9% Hb A, 3.5% Hb A2, 32.6% Hb G-Siriraj). In view of the family study results, the Hb Zürich-Langstrasse mutation in the proband was considered a de novo mutation occurring on the ßIVS-II-654 allele that he inherited from his mother, resulting in a ßIVS-II-654/Hb Zürich-Langstrasse genotype, which should be interpreted as a novel ß0 mutation. This report illustrates that mutations in cis can confound genotype-phenotype correlations, therefore, just as DNA testing and Hb analysis, family study is also indispensable to the accurate identification of ß-thal mutations.

Interpretation of clot-based lupus anticoagulant assays-Normalizing clotting time against different denominators.

OBJECTIVES: The endpoint for all lupus anticoagulant (LA) assays is a clotting time in seconds. This study aimed to clarify the use of normalizing clotting time to ratio and how the use of different denominators is relevant. METHODS: Whether normalization could reduce reagent variability and possess better diagnostic performances was assessed; denominators included reference interval (RI) mean, local-obtained pooled plasma clotting time, standard plasma clotting time, and control plasma clotting time (CNPPct). Moreover, whether day-to-day variation in CNPPct would impact its application was studied. RESULTS: If not normalized, significant difference existed among different reagent batches; if normalized (against any denominators), no statistically significant difference existed anymore. The validation of in-house RIs achieved a 100% success rate. Normalization against different denominators had different RIs, but the same diagnostic efficacies (when a prolonged LA1 is used to suggest further LA-related testings, normalized LA1 demonstrated a better sensitivity: 1.0 vs. 0.95). Normalization against a "daily" CNPPct (obtained alongside test plasmas day to day) demonstrated low inter-day variations (LA1: ~1%, LA2: ~1%), and it could employ the RI for normalization against a "fixed" CNPPct (obtained alongside normal plasmas when the RI was established). CONCLUSIONS: Normalizing clotting time reduces reagent-batch variability and promotes the adoption of common RIs, and therefore reduces the necessity of establishing RI for new reagent batches. Normalized LA1 is more sensitive when used to suggest further LA-related testings, and therefore reduces the rate of missed LA diagnosis. All denominators are of the same application value. Day-to-day variation in CNPPct did not impact its application as a reliable denominator.

Evaluation of Activated Partial Thromboplastin Time Mixing Studies Using Several Methods.

CONTEXT.­: A prolonged activated partial thromboplastin time (APTT), a vital screening test for coagulation, can be due to deficiencies in coagulation factors and the existence of factor inhibitors or antiphospholipid antibodies. APTT mixing studies are being optimized to help find the cause. OBJECTIVE.­: To optimize APTT mixing studies, we evaluated existing standards and explored when and how to combine 1:1 and 4:1 mixing. DESIGN.­: Patients with a prolonged APTT but otherwise normal prothrombin time and thrombin time were enrolled in our hospital from January 1, 2018, to December 31, 2019. All samples were subjected to 1:1 mixing studies, while 134 were subjected to 4:1. RESULTS.­: A total of 251 samples were involved, including 116 with factor deficiencies, 75 with FVIII inhibitors, and 60 with antiphospholipid antibodies. A Rosner index less than 11% or an extended incubation time of more than 3 seconds was better than other existing standards in differentiating factor deficiencies from inhibitors and in differentiating time-dependent inhibitors from time-independent inhibitors, but the approach presented here improves upon those. For the best diagnostic accuracy, samples with a Rosner index between 5.0% and 9.1% need a 4:1 mixing study, while others need 1:1. A combination of Rosner index and percent-extended incubation time-P seemed to offer objective and effective criteria for interpreting the results. CONCLUSIONS.­: APTT mixing studies had overall good sensitivity and specificity in differentiating factor deficiencies from inhibitors, or time-dependent from time-independent inhibitors. The combination of 1:1 and 4:1 mixing studies can improve the diagnostic ability compared with 1:1 alone.

Monitoring coagulation-fibrinolysis activation prompted timely diagnosis of hemophagocytic lymphohistiocytosis-related disseminated intravascular coagulation.

BACKGROUND: Timely diagnosis of disseminated intravascular coagulation (DIC) in hemophagocytic lymphohistiocytosis (HLH) patients is crucial but challenging, as HLH interferes with the results of the laboratory tests included in the DIC score system. CASE PRESENTATION: Here, we reported a case of lymphoma-associated HLH, in which coagulation-fibrinolysis activation /inhibition markers (TAT, tPAIC, and PIC), prompted timely diagnosis of early stage DIC (initial phase of microvascular thrombosis, yet non-overt), prior to the development of organ failures and/or bleedings. CONCLUSIONS: This report highlights the importance of the implementation of new biomarkers (such as TAT, tPAIC, and PIC), into the diagnostic work-up for coagulation disorders. These biomarkers are directly suggestive of microthrombus formation, therefore they can be of paramount importance in diagnosing DIC with complicated etiologies, such as hematological diseases-related DIC.

Design, synthesis, and biological evaluation of multiple targeting antimalarials.

Malaria still threatens global health seriously today. While the current discoveries of antimalarials are almost totally focused on single mode-of-action inhibitors, multi-targeting inhibitors are highly desired to overcome the increasingly serious drug resistance. Here, we performed a structure-based drug design on mitochondrial respiratory chain of Plasmodium falciparum and identified an extremely potent molecule, RYL-581, which binds to multiple protein binding sites of P. falciparum simultaneously (allosteric site of type II NADH dehydrogenase, Qo and Qi sites of cytochrome bc 1). Antimalarials with such multiple targeting mechanism of action have never been reported before. RYL-581 kills various drug-resistant strains in vitro and shows good solubility as well as in vivo activity. This structure-based strategy for designing RYL-581 from starting compound may be helpful for other medicinal chemistry projects in the future, especially for drug discovery on membrane-associated targets.

Platelet-leukocyte aggregates - a predictor for acute kidney injury after cardiac surgery.

BACKGROUND: Acute kidney injury (AKI) is one of the most common complications after cardiac surgery. However, effective biomarker used for early diagnosis of AKI has not been identified. Platelet-leukocyte aggregates (PLAs) participate in inflammation and coagulation, leading to vascular lesions and tissue destruction. We designed a prospective study to assess whether PLAs can serve as a good biomarker for early diagnosis of AKI after cardiac surgery. METHODS: Patients with rheumatic heart disease scheduled to undergo valve replacement surgery were enrolled. Blood samples were collected at five timepoints as follows: (a) At baseline. (b) At the end of extracorporeal circulation. (c) Arrival at intensive care unit (ICU). (d) Four-hours after the admission to ICU. (e) Twenty hours after the admission to ICU. After collection, the samples were immediately used for PLAs measurement by flow cytometry. RESULTS: A total of 244 patients were registered, and 15 of them were diagnosed with AKI according to the serum creatinine of KDIGO guidelines. The PLAs levels in AKI group were significantly increased 20 h after surgery (two-way repeated measure analysis of variance, p < 0.01) compared with that at baseline. Patients whose preoperative PLAs were higher than 6.8% showed increased risk of developing AKI (multivariate logistic regression; p = 0.01; adjusted odds ratio, 1.05; 95% confidence interval, 1.01-1.09). CONCLUSION: PLAs is an independent risk factor for AKI after valve replacement among patients with rheumatic heart disease.

Circ_0084043 Facilitates High Glucose-Induced Retinal Pigment Epithelial Cell Injury by Activating miR-128-3p/TXNIP-Mediated Wnt/ß-Catenin Signaling Pathway.

ABSTRACT: Diabetic retinopathy is a frequent complication of diabetes mellitus and one of the common causes of blindness. Circular RNAs (circRNAs) can modulate various biological behaviors of human diseases. Circ_0084043 is a novel circRNA, and its function in diabetic retinopathy progression is unclear. Adult retinal pigment epithelial cells (ARPE-19) were treated with high glucose (HG). RNA levels of circ_0084043, microRNA-128-3p (miR-128-3p), and thioredoxin-interacting protein (TXNIP) were detected by quantitative real-time polymerase chain reaction. 3-(4, 5-dimethylthiazole-2-y1)-2, 5-diphenyl tetrazolium bromide and flow cytometry were, respectively, used to examine cell viability and apoptosis. Apoptotic and TNXIP relative protein levels were measured by Western blot. The combination between targets was analyzed through dual-luciferase reporter assay or RNA immunoprecipitation assay. Results showed that HG induced the upregulation of circ_0084043 and the downregulation of miR-128-3p in ARPE-19 cells. Circ_0084043 knockdown or miR-128-3p overexpression mitigated the HG-mediated cell viability inhibition, apoptosis promotion, and inflammatory response. Circ_0084043 targeted miR-128-3p and miR-128-3p inhibitor returned the regulation of si-circ_0084043 in HG-treated cells. TXNIP was the target gene of miR-128-3p and TXNIP overexpression abolished the miR-128-3p-mediated effects after HG treatment. Circ_0084043 regulated the TXNIP expression to activate Wnt/ß-catenin signal pathway by targeting miR-128-3p. Our findings unraveled that circ_0084043 promoted the HG-induced retinal pigment epithelial cell injury through activating the Wnt/ß-catenin signal pathway by the miR-128-3p/TXNIP axis. Circ_0084043 might be an available biomarker in diabetic retinopathy diagnosis and therapy.

Dispensable Role of Mitochondrial Fission Protein 1 (Fis1) in the Erythrocytic Development of Plasmodium falciparum.

Malaria remains a huge global health burden, and control of this disease has run into a severe bottleneck. To defeat malaria and reach the goal of eradication, a deep understanding of the parasite biology is urgently needed. The mitochondrion of the malaria parasite is essential throughout the parasite's life cycle and has been validated as a clinical drug target. In the asexual development of Plasmodium spp., the single mitochondrion grows from a small tubular structure to a complex branched network. This branched mitochondrion is divided at the end of schizogony when 8 to 32 daughter cells are produced, distributing one mitochondrion to each forming merozoite. In mosquito and liver stages, the giant mitochondrial network is split into thousands of pieces and daughter mitochondria are segregated into individual progeny. Despite the significance of mitochondrial fission in Plasmodium, the underlying mechanism is largely unknown. Studies of mitochondrial fission in model eukaryotes have revealed that several mitochondrial fission adaptor proteins are involved in recruiting dynamin GTPases to physically split mitochondrial membranes. Apicomplexan parasites, however, share no identifiable homologs of mitochondrial fission adaptor proteins with yeast or humans, except for Fis1. Here, we investigated the localization and essentiality of the Fis1 homolog in Plasmodium falciparum, PfFis1 (PF3D7_1325600), during the asexual life cycle. We found that PfFis1 requires an intact C terminus for mitochondrial localization but is not essential for parasite development or mitochondrial fission. The dispensable role of PfFis1 indicates that Plasmodium contains additional fission adaptor proteins on the mitochondrial outer membrane that could be essential for mitochondrial fission.IMPORTANCE Malaria is responsible for over 230 million clinical cases and ∼half a million deaths each year. The single mitochondrion of the malaria parasite functions as a metabolic hub throughout the parasite's developmental cycle (DC) and also as a source of ATP in certain stages. To pass on its essential functions, the parasite's mitochondrion needs to be properly divided and segregated into all progeny during cell division via a process termed mitochondrial fission. Due to the divergent nature of Plasmodium spp., the molecular players involved in mitochondrial fission and their mechanisms of action remain largely unknown. Here, we found that the only identifiable mitochondrial fission adaptor protein that is evolutionarily conserved in the Apicomplexan phylum, Fis1, it not essential in P. falciparum asexual stages. Our data suggest that malaria parasites use redundant fission adaptor proteins on the mitochondrial outer membrane to mediate the fission process.

Genetic ablation of the mitoribosome in the malaria parasite Plasmodium falciparum sensitizes it to antimalarials that target mitochondrial functions.

The mitochondrion of malaria parasites contains several clinically validated drug targets. Within Plasmodium spp., the causative agents of malaria, the mitochondrial DNA (mtDNA) is only 6 kb long, being the smallest mitochondrial genome among all eukaryotes. The mtDNA encodes only three proteins of the mitochondrial electron transport chain and ∼27 small, fragmented rRNA genes having lengths of 22-195 nucleotides. The rRNA fragments are thought to form a mitochondrial ribosome (mitoribosome), together with ribosomal proteins imported from the cytosol. The mitoribosome of Plasmodium falciparum is essential for maintenance of the mitochondrial membrane potential and parasite viability. However, the role of the mitoribosome in sustaining the metabolic status of the parasite mitochondrion remains unclear. The small ribosomal subunit in P. falciparum has 14 annotated mitoribosomal proteins, and employing a CRISPR/Cas9-based conditional knockdown tool, here we verified the location and tested the essentiality of three candidates (PfmtRPS12, PfmtRPS17, and PfmtRPS18). Using immuno-EM, we provide evidence that the P. falciparum mitoribosome is closely associated with the mitochondrial inner membrane. Upon knockdown of the mitoribosome, parasites became hypersensitive to inhibitors targeting mitochondrial Complex III (bc1), dihydroorotate dehydrogenase (DHOD), and the F1F0-ATP synthase complex. Furthermore, the mitoribosome knockdown blocked the pyrimidine biosynthesis pathway and reduced the cellular pool of pyrimidine nucleotides. These results suggest that disruption of the P. falciparum mitoribosome compromises the metabolic capacity of the mitochondrion, rendering the parasite hypersensitive to a panel of inhibitors that target mitochondrial functions.

Prediction of mortality and organ failure based on coagulation and fibrinolysis markers in patients with acute pancreatitis: A retrospective study.

This study explored the predictive value of coagulation and fibrinolysis markers with acute pancreatitis (AP)-related mortality and organ failure.We retrospectively reviewed and analyzed coagulation and fibrinolysis markers and clinical outcomes of the patients with AP.A total of 273 patients with AP were enrolled, 7 patients died and 28 patients suffered from organ failure. Uni- and multivariate logistic regression identified the differences of all of the coagulation and fibrinolysis markers as risk factors for AP-related mortality. The differences of APTT value, TT value, D-dimmer level, FDP level, and AT III level were risk factors for organ failure. Furthermore, the OR of the differences of platelet, PT, APTT, TT, fibrinogen, D-dimmer, FDP, and AT III was substantially improved by grouping with intervals of 10 × 10/L, 2 seconds, 5 seconds, 3 seconds, 0.5 g/L, 3 mg/L FEU, 5 mg/L and 10%, respectively. The risk of mortality can increase up to 1.62, 5.17, and 5.60 fold for every 10 × 10/L, 2 seconds and 5 seconds of increase in platelet, PT and APTT, respectively. There is approximate 2-fold increase in risk of organ failure for every 2 seconds of TT increase. In receiver operating characteristic analysis, there is no difference in the predictive power of bedside index for severity in acute pancreatitis (BISAP) with them in mortality or organ failure.In patients with AP, the dynamic changes of coagulation and fibrinolysis markers are good predictors for AP-related mortality and organ failure, especially platelet, PT and APTT in mortality and TT in organ failure.

Peak urea level, leukocyte count and use of invasive ventilation as risk factors of mortality in acute pancreatitis: A retrospective study.

BACKGROUND: Acute pancreatitis (AP) is associated with high complications. Early, reliable prediction of mortality may improve patient management. METHODS: We retrospectively reviewed medical records of 1,599 patients with AP treated at a single large hospital in southwest China. Models to predict mortality were derived from a subset of 1,062 patients (development dataset), and the models were then validated in the remaining 537 patients (validation dataset). Independent risk factors and prediction models for mortality were identified using logistic regression. RESULTS: A total of 33 patients in the development dataset and 13 in the validation dataset died during hospitalization. Independent risk factors for mortality were found to be plasma urea levels, glucose levels and platelet counts at admission; as well as peak urea levels, leukocyte counts and use of invasive ventilation during hospitalization. Based on the development dataset, a mortality prediction model based only on urea level at admission gave an area under the curve (AUC) of 0.81, which did not significantly improve by incorporating glucose level or platelet count at admission. Significantly better was a model taking into account three in-hospital parameters: peak urea level, leukocyte count and use of invasive ventilation (AUC 0.97). CONCLUSIONS: While mortality of AP patients can be predicted reasonably well based only on urea values at admission, predictions are more reliable when they take into account in-hospital data on peak urea level, leukocyte count and use of invasive ventilation.

[Adjusting Platelet Counts for Platelet Aggregation Tests].

OBJECTIVE: To explore a better method to adjust platelet counts for light transmission aggregometry (LTA). METHODS: Blood samples from 36 healthy participants aged from 18 to 50 yr. were collected.Platelet-rich plasma (PRP) was diluted using platelet-poor plasma (PPP) and physiological saline (PS),respectively,in a ratio of 1.5,2,2.5 and 3 times. Platelet aggregation was induced by adenosine diphosphate (ADP),arachidonic acid (ARA),collagen (COL), epinephrine (EPI),or ristocetin (RIS). The maximal aggregation rates (MAs) of different approaches were compared. We also compared the MAs induced by RIS between PRP-obtained-PPP and whole blood-obtained-PPP (2 100×g, 5 min). RESULTS: Compared with the original PRP,the MAs induced by ADP,ARA,and EPI decreased in PPP-adjusted PRP (significant at 2-3 times dilution ratio,P<0.05),but not in PS-adjusted PRP (P>0.05). The MA induced by RIS decreased in PS-adjusted PRP (significant at all dilution ratios,P<0.05),but not in PPP-adjusted PRP (P>0.05). No changes in the MA induced by COL were found in PS-adjusted PRP and PPP-adjusted PRP (P>0.05). Whole blood-obtained-PPP (2 100×g, 5 min) had the same MA induced by ristocetin compared with PRP-obtained-PPP (P>0.05). CONCLUSION: PS is recommended for adjusting platelets counts for platelet aggregation induced by ADP,ARA,COL and EPI. Whole blood-obtained-PPP (2 100 ×g, 5 min) is recommended for RIS-induced aggregation as a matter of convenience.

A Phenotypically Unusual Hemoglobin H Disease Resulting from a Rare α-Globin Genotype (-SEA/-α27.6).

Hemoglobin H (Hb H) disease is usually characterized by the existence of Hb H, which influences the degree of functional anemia. We here report a patient with a rare Hb H disease genotype (-SEA/-α27.6), who was observed to paradoxically have no detectable Hb H fraction on electrophoresis. To date, the reason why the quantity of Hb H component and the clinical presentation in Hb H disease vary widely is still incompletely understood. Our report demonstrates a possible explanation - the different degradation ability of excess ß-globin chains, which might be regulated by the 27.6 kb sequence of α-globin gene.

Capillarys 2 Flex Piercing Detected a Rare Case of Hb Broomhill.

We report a case of an extremely rare hemoglobin (Hb) variant-Hb Broomhill, which has been only reported once in the literature. Hemoglobin fractions were determined by capillary electrophoresis (Sebia Capillarys 2 Flex piercing) and high performance liquid chromatography (HPLC) (Bio-Rad Variant™ II Hemoglobin Testing System), respectively. Complete blood count and DNA sequencing were also performed. The capillary electrophoregram revealed a tiny shoulder peak before the HbA peak and a subtle abnormal HbA2 peak (slightly wider and lower), even though the percentage of each hemoglobin fraction was within the reference range (HbA, 97.4%; HbA2, 2.6%). On HPLC, not only the percentage but also the peak shape of each hemoglobin fraction was normal (HbA 88.2%, HbA2 2.5%, HbF 0.6%). Eventually, sequencing analysis of α genes confirmed a missense mutation (CCC>GCC at codon 114 in alpha1 gene) which caused Hb Broomhill variant. Our report suggest that capillary electrophoresis may be an accurate tool for screening and diagnosis of Hb disorders.

[Effects of Danqi Capsule on Platelet Function in Healthy People].

OBJECTIVES: To study the effects of Danqi Capsule on platelet function in healthy people. METHODS: Sixteen healthy volunteer were divided into low dose (4 capsules/time, 3 times/d) and high dose group (6 capsules/time, 3 times/d), and received Danqi Capsule by orally administration for 2 weeks. The venous blood were collect at 3 time points: one week before taking Danqi Capsule (control), one week after taking Danqi Capsule (1 week), two week after taking Danqi Capsule (2 weeks). Blood samples were used for the measurements of conventional coagulation examination, complete blood count, liver and kidney function test, platelet aggregation test, the plasma levels of P-selectin and von Willebrand factor (vWF) , and maximum aggregation (MA). RESULTS: In both dosage group, Danqi capsule(1 week/2 weeks) administration showed no difference in conventional coagulation examination, complete blood count, liver and kidney function test, or the plasma level of vWF ( P>0.05), but showed difference (decreased) in platelet aggregation test and the plasma level of P-selectin (vs. control, P<0.05). CONCLUSIONS: Danqi Capsule inhibits platelet activation and platelet aggregation, but not affects the plasma level of vWF, the coagulation function or the hepatorenal function in normal subjects.

Evaluation of an automated light transmission aggregometry.

Light transmission aggregometry (LTA) is the "gold standard" for platelet function assessment, but it is time-consuming and labor intensive. Recently, an automated platelet aggregation method has been developed on a routine coagulation analyzer (Sysmex CS-2100i). In this study, the performances of CS-2100i including repeatability, correlation with a reference aggregometer (Chrono-log Model 700), and the threshold limitation of platelet counts in platelet-rich plasma (PRP) were evaluated for clinical use. The agonists were adenosine diphosphate (ADP), arachidonic acid, collagen, epinephrine, and ristocetin. The platelet concentration of PRP was adjusted with platelet-poor plasma (PPP) and physiological saline (PS). The CS-2100i showed an excellent repeatability and a strong correlation with the Chrono-log 700 in performing platelet aggregation, and its threshold limitation of platelet counts in PRP was 80 × 109/L. PPP had an inhibitory impact on platelet aggregation induced by ADP, arachidonic acid, collagen or epinephrine; while PS had an inhibitory impact on ristocetin-induced aggregation. PS should be used to adjust PRP for ADP-, arachidonic acid-, collagen-, or epinephrine-induced aggregation; while PPP was recommended for ristocetin-induced aggregation. The CS-2100i showed an excellent repeatability, a strong correlation with Chrono-log 700, a lower platelet count requirement, a shorter turnaround time for samples, the advantage of being a walk-away technology, and the ability to perform a highly standardized platelet function assessment.

Intestinal absorption characteristics of imperialine: in vitro and in situ assessments.

AIM: Imperialine is an effective compound in the traditional Chinese medicine chuanbeimu (Bulbus Fritillariae Cirrhosae) that has been used as antitussive/expectorant in a clinical setting. In this study we investigated the absorption characteristics of imperialine in intestinal segments based on an evaluation of its physicochemical properties. METHODS: Caco-2 cells were used to examine uptake and transport of imperialine in vitro, and a rat in situ intestinal perfusion model was used to characterize the absorption of imperialine. The amount of imperialine in the samples was quantified using LC-MS/MS. RESULTS: The aqueous solubility and oil/water partition coefficient of imperialine were determined. This compound demonstrated a relatively weak alkalinity with a pKa of 8.467±0.028. In Caco-2 cells, the uptake of imperialine was increased with increasing pH in medium, but not affected by temperature. The apparent absorptive and secretive coefficient was (8.39±0.12)×10(-6) cm/s and (7.78±0.09)×10(-6) cm/s, respectively. Furthermore, neither the P-glycoprotein inhibitor verapamil nor Niemann-Pick C1-Like 1 transporter inhibitor ezetimibe affected the absorption and secretion of imperialine in vitro. The in situ intestinal perfusion study showed that the absorption parameters of imperialine varied in 4 intestinal segments (duodenum, jejunum, ileum and colon) with the highest ones in the colon, where a greater number of non-ionized form of imperialine was present. CONCLUSION: The intestinal absorptive characteristics of imperialine are closely related to its physicochemical properties. The passive membrane diffusion dominates the intestinal absorption of imperialine.