Analysis of Relationship between Coagulation Function and Blood Transfusion in Patients with Emergency Rescue / 中国实验血液学杂志

<p><b>OBJECTIVE</b>Through researching preoperative coagulation function in the case of ABO-identical blood insufficient for emergency rescue transfusion according to recommended programs of special emergency rescue transfusion was carried out, the relationship between volume of blood products and coagulation function was analyzed.</p><p><b>METHODS</b>The surgical cases of blood transfusion more than 1 600 ml during operation were collected in our hospitals from Aug 2015 to Dec 2016（n=218）, these cases were divided into the normal coagulation group（Group A） and abnormal coagulation group（Group B）, and the patients of emergency rescue transfusion O type blood group（Group C）. The basic information of cases, the infused volume of red blood cell（RBC）, virus-inactivated frozen plasma（VIFP）, fresh frozen plasma（FFP）, cryoprecipitate（C）and platelets（P）, prothrombin time（PT）, activated partial thromboplastin time（APTT）, fibrinogen（FIB）and international normalized ratio（INR）were analyzed, the relationship between volume of blood transfusion and coagulation function were also analysed. At the same time, the efficiency and safety index were compared before and after transfusion. These indexes, such as hemoglobin（Hb）, indirect bilirubin（IBiL）, direct antiglobulin test（DAT）and irregular antibody were determined at the time-paints of 24 h, 3 d and 7 d after blood transfusion.</p><p><b>RESULTS</b>The differences of age and blood type between group A and B was not statistically significant（P>0.05）. Proportion of A and AB type，transfusion volume of RBC, FFP, C and Plt all were significantly higher in group C （P<0.05）. PT, APTT, FIB and INR in group B and C were significantly different（P<0.05）, which related with the transfusion volume of RBC, FFP and C（P<0.05）. DAT and irregular antibody in every group was all negative before transfusion, No any new irregular antibodies had been detected after transfusion. Hb after blood transfusion was not statistically different before and after transfusion in group C, the IBiL level also was not significantly increased after blood transfusion（P > 0.05）. All those showed that emergency rescue transfusion was safe and effective.</p><p><b>CONCLUSION</b>Preoperative coagulation function is one of factors inflnencing blood products transfusion volume during operation, which also is the basis for evaluating bleeding and blood transfusion. Emergency O type blood and ABO-matched blood transfusions show the same efficiency and safety.</p>

Experimental Study on Neonatal ABO or RhD Compatible Blood Transfusion / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the safety and effectiveness of neonatal ABO or Rh(D) by using compatible blood transfusion through retrospective analysis of data from cases received compatible blood transfusion and type matched blood transfusion.</p><p><b>METHODS</b>The clinical data of 26 cases of neonatal compatible blood transfusion in Chinese Nanchang area from January 2014 to October 2016 were collected, and 26 cases of neonatal type-matched blood transfusion were selected according to ratio of 1:1 cases. The efficiency and safety index of 26 patients compatible blood transfusion were compared with that of type-matched blood transfusion. The efficiency indexes included: patients' basic characteristics, red blood cell (RBC) count, hemoglobin (Hb) level, hematocrit (Hct), and the safety indexes contain Hb level and indirect bilirubin (IBiL) value before and after blood transfusion, irregular antibody screening, direct antiglobulin test (DAT) results and the adverse reactions of blood transfusion.</p><p><b>RESULTS</b>The age, sex, days of hospitalization between compatible blood transfusion and type matched blood transfusion were not statistically significantly different (P>0.05). The Hb level before transfusion, blood transfusion volume and the increase of Hb, Hct and RBC were not statistically significantly different between two groups (P>0.05). The values of Hb, Hct and RBC in 2 groups significantly increased at the day 1 after blood transfusion (P<0.05). No blood transfusion adverse reaction occurred in 2 groups. The IBiL value significantly decreased in compatible blood transfusion patients at the day 1 after blood transfusion (P<0.05). No new irregular antibodies had been detected after transfusion in all patients, and the others' DAT and screening for irregular antibodies were negative except 22 patients with neonatal hemolysis. The values of Hb and IBiL statistically significantly differenence were not in 12 patients between 1d, 3d, 7d after blood transfusion (P>0.05).</p><p><b>CONCLUSION</b>The efficiency and safety between compatible blood transfusion and type matched blood transfusion are the same in neonatal blood transfusion. Compatible blood transfusion is a safe and effective in clinical blood transfusion.</p>

Key Preparation Technique and Clinical Application of Frozen Platelets / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the key technique for preparation of the frozen platelet and efficacy of its clinical application.</p><p><b>METHODS</b>The influences of the donators' peripheral platelet count, starting time of freeze, injection rate and evenness of the freeze-protective agent, storage mode, re-melting temperature and the capacity of water-bath etc. on the quality of the frozen platelets were analyzed retrospectively in 3 257 samples of frozen platelets before platelet pheresis. Then, the platelet counts were examined in 150 cases transfused with frozen platelets at the time-points of 1, 24, 48 and 72 hrs after transfusion, 90 cases suffered from the obstetrical bleeding were transfused with 200 parts of the re-melting frozen platelets, and then the peripheral blood platelet count, platelet increasing index(CCI), bleeding time and blood clot retraction rate etc. were observed for determining the clinical efficiency of the frozen platelets.</p><p><b>RESULTS</b>The floccule in the re-melting frozen platelets from the donators with (175-250)×10(9)/L platelets were decreased significantly(P<0.01). The quality of frozen platelets was influenced by the following factors, such as injection of DMSO at a too fast and heterogeneous rate, blood bags stored in a multilamminar space, and re-melting in a water-bath of small capacity etc. The routine storage for 0 and 3 days did not influence the quality of the frozen platelets. The recovery rate of one year-freezing platelets all was higher than 80%. The effects of the frozen platelets transfused into the patients with obstetrical bleeding displayed good haemostatic results, and the blood transfusion reaction did not occur. However, the frozen platelets immediately were exhausted and displayed their function, but the counting after 48 hrs could not display a good effect of raising platelet number.</p><p><b>CONCLUSIONS</b>The peripheral platelet count before platelet pheresis, the injection rate and evenness of the protective agent, the number of stratum for blood bags and the capacity of re-melting water-bath etc. all are the key factors influencing the quality of the frozen platelets. The frozen platelets prepared in this study shows a good efficacy of clinical application.</p>

Antiarrhythmic ionic mechanism of Guanfu base A--Selective inhibition of late sodium current in isolated ventricular myocytes from guinea pigs / 中国天然药物

The present study was designed to determine the effects of Guanfu base A (GFA) on the late sodium current (INa.L), transient sodium current (INa.T), HERG current (IHERG), and Kv1.5 current (IKv1.5). The values of INa.L, INa.T, IHERG and IKv1.5 were recorded using the whole-cell patch clamp technique. Compared with other channels, GFA showed selective blocking activity in late sodium channel. It inhibited INa.L in a concentration-dependent manner with an IC50 of (1.57 ± 0.14) μmol · L(-1), which was significantly lower than its IC50 values of (21.17 ± 4.51) μmol · L(-1) for the INa.T. The inhibitory effect of GFA on INa,L was not affected by 200 μmol · L(-1) H2O2. It inhibited IHERG with an IC50 of (273 ± 34) μmol · L(-1) and has slight blocking effect on IKv1.5, decreasing IKv1.5 by only 20.6% at 200 μmol · L(-1). In summary, GFA inhibited INa.L selectively and remained similar inhibition in presence of reactive oxygen species. These findings may suggest a novel molecular mechanism for the potential clinical application of GFA in the treatment of cardiovascular disorders.

Influence of S-nitrosoglutathione on the membrane glycoprotein of frozen platelets / 中国实验血液学杂志

This study was purposed to explore the influence of S-nitrosoglutathione (GSNO) on membrane glycoprotein of frozen platelet. The levels of membrane glycoprotein on fresh liquid platelets, frozen platelets and frozen platelets with GSNO were measured by flow cytometry. The results showed that the GSNO obviously decreased platelet aggregation, the PAC-1 change in the three groups was not significant. The changes of CD42b and CD62P in fresh liquid platelet group, frozen platelet group and frozen platelets with GSNO were significant different. The change of membrane glycoprotein in above-mentioned three group was not significant. It is concluded that the GSNO inhibits platelet aggregation, maintains the function of platelets and may be used as a cryoprotectant. When frozen platelets were added with GSNO, the molecular rearrangement, structure change and other mechanism may occur in platelets.

Effect of trehalose-loading on red blood cell membrane / 中国实验血液学杂志

This study was purposed to evaluate the effect of trehalose-loading on physiological and biochemistry properties of red blood cell (RBC) membrane. The samples were divided into the control group (RBC without trehalose loading) and the test group (RBC with trehalose loading). Osmotic fragility reaction was used to determine the osmotic fragility change of loaded RBC membrane in NaCl solution of different osmotic concentration. Flow cytometry and deformeter were used to assay the integrality and deformability of the RBC, respectively. The results showed that the NaCl solution osmotic concentrations were 160 mOsm and 121.4 mOsm, respectively when the haemolysis rate was 50% of the control group and the test group. Flow cytometry data demonstrated that incubation of RBC in a hypertonic trehalose solution resulted in a fraction of cells with different complexity that attached to little Annexin V-FITC, and that it could be removed by washing and resuspending the RBC in an iso-osmotic (300 mOsm PBS) medium. The deformability of the loaded RBC descend, the statistical difference was significant between control and test groups (P < 0.01). It is concluded that the membrane physiological and biochemistry stability and membrane integrality of RBC in a hyper osmotic pressure can be retained after trehalose loading.

Influence of S-nitrosoglutathione on agglutination and nitric oxide concentration in frozen platelets / 中国实验血液学杂志

The aim of this study was to investigate the influence of S-nitrosoglutathione (GSNO) on agglutination and nitric oxide (NO) concentration in frozen platelets. The agglutination of platelets was detected by using platelet agglutination apparatus, the level of NO in platelets was detected by the nitrate enzyme reduction method. The results showed that the rates of agglutination in freeze platelets and frozen platelets treated with GSNO were (35.47 ± 2.93) and (24.43 ± 3.07), which were significantly lower than that in fresh liquid platelets (63.44 ± 2.96). The level of NO concentration in frozen platelets was (22.16 ± 6.38), which was significantly lower than that in fresh liquid platelets (31.59 ± 16.88). The level of NO concentration in frozen platelets treated with GSNO was (45.64 ± 6.31), which was significantly higher than that in fresh liquid platelets (P < 0.01). It is concluded that GSNO increases the concentration of NO in frozen platelets, inhibits platelet activation and maintains platelet function, thus GSNO can be used as a frozen protective agent.

Recent research advances on cryopreserved platelets / 中国实验血液学杂志

The right choice of frozen protective agents and additives is an important factor to ensure the quality of frozen platelets. The immediate hemostatic function of frozen platelet in vivo is superior to liquid-stored platelets. In order to ensure the quality of frozen platelets better, it is important to understand the role of dimethylsulfoxide (DMSO) in the preservation of frozen platelets and its mechanism, and to understand the mechanism of DMSO enhancing the hemostatic function of frozen platelets and the effects of different factors on the frozen platelets. In this review, the long-term preservation of frozen platelets and its quality standards, the mechanism of DMSO effect on the molecular changes and inhibition of frozen platelets, different factors influencing preservation freezing platelets and the test of preservation effects, the application of frozen platelets to the military operation and disaster relief, the canine frozen platelet studies and so on are summarized.

Optimization of lyophilization procedures for freeze-drying of human red blood cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the different parameters of the lyophilization procedures that affect the recovery of the rehydrated red blood cells (RBCs).</p><p><b>METHODS</b>Human RBCs loaded in tubes were cooled with 4 different modes and subjected to water bath at 25 degrees celsius;. The morphological changes of the RBCs were observed to assess the degree of vitrification, and the specimens were placed in the freeze-dryer with the temperature set up at 40, -50, -60, -70 and -80 degrees celsius;. The rates of temperature rise of the main and secondary drying in the lyophilization procedures were compared, and the water residue in the specimens was determined.</p><p><b>RESULTS</b>The protectant did not show ice crystal in the course of freezing and thawing. No significant difference was found in the recovery rate of the rehydrated RBCs freeze-dried at the minimum temperature of -70 degrees celsius; and -80 degrees celsius; (P > 0.05). The E procedure resulted in the maximum recovery of the RBCs (83.14% ± 9.55%) and Hb (85.33% ± 11.42%), showing significant differences from the other groups(P < 0.01 or 0.05). The recovery of the RBCs showed a positive correlation to the water residue in the samples.</p><p><b>CONCLUSION</b>Fast cooling in liquid nitrogen and shelf precooling at -70 degrees celsius; with a moderate rate of temperature rise in lyophylization and a start dry temperature close to the shelf equilibrium temperature produce optimal freeze-drying result of human RBCs.</p>

Optimization of composition and concentration for lyophlizing protectant of human red blood cells / 中国实验血液学杂志

This study was purposed to investigate the effect of different compositions and concentrations of lyophilizing protectants on recovery of RBCs and hemoglobin (Hb) after rehydration of lyophilized RBCs. The RBC lyophilizing protectants composed of a series concentrations of PVP, trehalose and different osmotic protectants were applied for protecting lyophilizing process of RBCs, the recovery of RBCs and Hb after rehydration of lyophilized RBCs was detected. The results showed that there were significant differences in loss ratio of RBCs between protectants composed of different compositions and concentrations (p<0.05 or p<0.01). The loss ratio of RBCs in protectant containing 30% PVP40, 150 mmol/L trehalose and 2% BSA was minimum (0.02%), the loss ratio of RBCs in protectant containing 6% PVP 360, 100 mmol/L trehalose and 2% BSA was maximum (0.27%). The difference of effect between 150 and 50 mmol/L trehalose was statistically significant (p<0.01). The recovery rates of RBCs and Hb in protectants contained PVP40 of different concentrations were different after rehydration of lyophilized RBCs. The protectant containing 15% PVP40, 150 mmol/L trehalose and 2% BSA showed optimal protective efficacy for lyophilized RBCs, the recovery rates of RBCs and Hb were 61.29+/-4.11% and 62.49+/-5.91% respectively, which were statistically different from other protectants (p<0.01). The protectants containing glycerol displayed best efficiency in lyophilization too, the recovery rates of RBCs and Hb were 65.97+/-4.52% and 67.24+/-5.94%, respectively. It is concluded that the protectants composed of 0.8 mol/L glycerol, 15% PVP40, 150 mmol/L trehalose and 2% BSA (pH 7.3 ) may be used as the protectant lyophilizing human RBCs in future study.

Preliminary study on rehydrated conditions for lyophilized human red blood cells / 中国实验血液学杂志

The objective of this study was to investigate the effect of different rehydration conditions on recovery of the lyophilized red blood cells (RBC) so as to optimize the RBC rehydration. The different conditions, including different rehydration solution, the rehydration temperature, volume change rate of the lyophilized RBC rehydrated by the vapor firstly, were studied, the recovery rate and change of physiological and biochemical properties of the rehydrated RBC were detected. The results indicated that the solution of 10% (w/v) PVP40 in PBS showed the best effect, and the RBC recovery rate increased with increasing of rehydration temperature, and the optimal temperature of rehydration was at 37 degrees C. Pre-rehydration in condition of vapor could raise the RBC recovery rate, and promote the MCV and RDW to close to index of the fresh RBC, the deformability of the rehydrated RBC was no serious as compared with RBC preserved in conventional condition, but the activity level of ATP, G-6-PD, SOD, 2, 3-DPG of the rehydrated RBC less decreased. It is concluded that the optimal rehydration conditions for lyophilized RBC are pre-rehydration in the 37 degrees C with vapor firstly, PBS + 10% (w/v) PVP40 rehydration solution and rehydration temperature at 37 degrees C, but the protection of RBC membrane needs to be furtherly studied.

Cryopreservation strengthens procoagulative activities of platelets / 中国实验血液学杂志

The aim of this study was to explore the potential relationship between the enhancement of instant hemostatic function in vivo of cryopreserved platelets and its procoagulative related molecule activities. The ability of platelet binding factor V density of GPIb-IX-V (CD42a) at platelet member surface were detected by flow cytometry, the clotting time induced by activated platelets were evaluated by coagulometer and platelet count, MPV and PDW were measured by hemocytometer before and after fresh platelets were cryopreserved. The results showed that the clotting time induced by activated cryopreserved platelets decreased by 43.9%, even quicker than that induced by fresh platelets; the fluorescence intensity of cryopreserved platelet binding factor V increased by 117%, more than that of fresh platelets binding factor V; the GPIb-IX-V (CD42a) density at cryopreserved platelet membrane surface increased by 32%, higher than that at fresh platelet surface. It is concluded that the enhancement of instant hemostatic function in vivo of cryopreserved platelet may be related to higher expression of procoagulative molecules or to their enhanced activity and rapid hemostatic effect.

Inhibition of L-arginine and cilostazol on activation of platelets in vitro / 中国实验血液学杂志

The purpose of study was to investigate the effects of L-arginine and cilostazol on platelet-activation and aggregation reserve in vitro, so as to provide proof for selecting reversible activation-inhibitors for platelets lyophilization. Activation and function of platelets were investigated by using flow cytometry with the CD62p and PAC-1 expression and re-expression after being activated by thrombin, and by means of platelet aggregation reaction to thrombin, ADP and propyl gallate, as well as coagulation activity of platelets. The results showed that expression of CD62p and PAC-1 increased after being pretreated. Both L-arginie and cilostazol could inhibit CD62p and PAC-1 expression and related with their concentrations. Cilostazol had an intensive inhibition effect on expressions of CD62p and PAC-1 induced by thrombin, and the inhibition increased when concentration augmented. L-arginine had the same effects on PAC-1, but had no effects on CD62p. L-arginine and cilostazol inhibited aggregation induced by thrombin, ADP and propyl gallate, and the inhibitions were related directly with dosage. When L-arginine concentration was higher or equal to 15 mmol/L, or cilostazol concentration was in range of 1 - 4 mmol/L, the aggregation time were prolonged so much or even no aggregation. It is concluded that when L-Arginine concentration is 5 mmol/L and 10 mmol/L, platelet activation can be inhibited, but aggregation ability and characters keep intact. Concentration at 5 mmol/L may be the best. 1 mmol/L of cilostazol can inhibit activation in vitro and retain part of platelet ability of aggregation and reexpression.

Experimental study on lyophilization of platelets / 中国实验血液学杂志

The aim of this study was to search a procedure of platelet lyophilization and find a way of long-term storage of human platelets at normal temperature with smaller size and lighter weight, to be convenient to transport at long distance thus to meet the demands in accidents and war time. Human platelets were pretreated by freezing, the first and the second desiccation, and were added with reversible activation-inhibitors of platelets, DMSO and trehalose, then were rehydrated. At the same time, the recovery rate of platelets, platelet maximal aggregation induced by thrombin, coagulation of platelets, CD62p expression and PAC-1 expression were assayed. The results indicated that the recovery rate of the platelets was 56.29%. The platelet maximal aggregation induced by thrombin had no significant difference between lyophilized platelets and the fresh platelet-rich plasma (FPRP), but the aggregation of platelets induced by ADP or propyl gallate was decreased by 49.34% and 26.25%. Coagulation of the lyophilized platelets was not significantly different from FPRP. CD62p expression of the lyophilized platelets (42.36%) was higher than that in FPRP while PAC-1 expression was 2.12%. CD62p re-expression rate induced by thrombin was 50.88% and PAC-1 re-expression was 54.55%. It is concluded that the ability of recovered lyophilized platelets added with reversible activation-inhibitors, DMSO and trehalose to aggregate and coagulate has showed no significant difference as compared with FPRP. The reversible activation-inhibitors can decrease CD62p expression of lyophilized platelets, and may enhance their survival ability and prolongate survival time. Therefore the efficiency of lyophilizing platelets can be improved based on this freeze-drying procedure.

Efficacy of intravenous Acehytisine Hydrochloride versus propafenone on terminating paroxysmal supraventricular tachycardia: a double-blinded, randomized multi-center study / 中华心血管病杂志

<p><b>OBJECTIVE</b>In this double-blinded, randomized, parallel study, we investigated the clinical efficacy of intravenous Acehytisine Hydrochloride (AHH) and propafenone on terminating paroxysmal supraventricular tachycardia (PSVT).</p><p><b>METHODS</b>Patients (18 - 70 years old) with either spontaneous or induced sustained supraventricular tachycardia lasted at least 15 min were recruited in this study. Exclusion criteria included sick sinus syndrome, atrial ventricular block or intraventricular block, etc. Eligible patients were randomly assigned to receive intravenously AHH (n=101) or propafenone (n=100) according to a proportion of 1:1 in a double-blinded manner. AHH (4 mg/kg, iv.) or propafenone (PRO, 1 mg/kg, iv.) was administered in 5 min followed by the same dose if no response was observed. Conversion times, vital signs, electrocardiograms were documented before and after drug administration.</p><p><b>RESULTS</b>Except for age, the demographic characteristics and clinical features were comparable between the two groups. Efficacy on PSVT termination was comparable between AHH (72/101, 71.3%) and PRO group (73/100, 73.0%, P=0.6368). The average time from drug administration to conversion was also similar [AHH: (9.62 +/- 8.39) min vs. PRO: (10.61 +/- 9.47) min, P=0.5035]. In the AHH group, 59/72 episodes of PSVT were terminated by the first dose, and 66/72 were terminated prematurely. The average AHH dose in the 72 converted patients was (273.7 +/- 111.2) mg. In the PRO group, 54/73 episodes of PSVT were terminated by the first dose. The electrocardiographic parameters, such as sinus recovery time, longest PP and RR interval, PR interval, QRS interval, QT interval after conversion were similar between the two groups. Transient adverse events were reported in 11/101 (10.9%) patients in the AHH group and in 18/100 (18.0%,) in the PRO group (P=0.1653).</p><p><b>CONCLUSION</b>With the dosage used in the present study, the efficacy on terminating PSVT was comparable between AHH and PRO.</p>

Optimization of trehalose loading in red blood cells before freeze-drying / 中国实验血液学杂志

The key points for better protection of trehalose in freeze-drying red blood cells (RBCs) are to resolve non-osmosis of trehalose to red blood cells and to make cytoplasmic trehalose to reach effective concentration. This study was aimed to investigate the regularity of loading RBCs with trehalose, screen out optimal loading condition and evaluate the effect of trehalose on physico-chemical parameters of RBCs during the period of loading. The cytoplasmic trehalose concentration in red blood cells, free hemoglobin and ATP level were determined at different incubation temperatures (4, 22 and 37 degrees C), different trehaolse concentrations (0, 200, 400, 600, 800 and 1000 mmol/L) and different incubation times (2, 4, 6, 8 and 10 hours), the cytoplasmic trehalose, free hemoglobin (FHb), hemoglobin (Hb) and mean corpuscular volume (MCV) in fresh RBCs and RBCs stored for 72 hours at 4 degrees C were compared, when loading condition was ensured. The results showed that with increase of incubation temperature, time and extracellular trehalose concentration, the loading of trehalose in RBCs also increased. Under the optimal loading condition, cytoplasmic trehalose concentration and free hemoglobin level of fresh RBCs and RBCs stored for 72 hours at 4 degrees C were 65.505 +/- 6.314 mmol/L, 66.2 +/- 5.002 mmol/L and 6.567 +/- 2.568 g/L, 16.168 +/- 3.922 g/L respectively. It is concluded that the most optimal condition of loading trehalose is that fresh RBCs incubate in 800 mmol/L trehalose solution for 8 hours at 37 degrees C. This condition can result in a efficient cytoplasmic trehalose concentration. The study provides an important basis for long-term preservation of RBCs.

Isolation and identification of hetisine-type alkaloids from Aconitum coreanum by high speed countercurrent chromatography / 药学学报

<p><b>AIM</b>To search for more bioactive compounds from the roots of Aconitum coreanum (Lèvl.) Rapaics.</p><p><b>METHODS</b>High speed countercurrent chromatography was successfully applied to the separation of alkaloids from Aconitum coreanum. The structures were elucidated by their physicochemical properties and spectroscopic analysis.</p><p><b>RESULTS</b>Two-phase solvent system composed of CHCl3-CH3OH-0.2 mol x L(-1) HCl (10:3:3, volume ratio) was used in this experiment, eight alkaloids were obtained from the roots of Aconitum coreanum, which were identified as: 2alpha-propionyl-11alpha,13beta-diacetyl-14-hydroxyhetisine (I), Guanfu base P (II), Guanfu base G (III), Guanfu base F (IV), Guanfu base Z (V), Guanfu base O (VI), Guanfu base A (VII), Guanfu base B (VIII).</p><p><b>CONCLUSION</b>Compound I is a new alkaloid, named Guanfu base R.</p>

Effect of Guanfu Base A in patients with ventricular arrhythmias / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the effect and safety of intravenous Guanfu Base A hydrochloride (GFA) in the treatment of ventricular arrhythmias.</p><p><b>METHODS</b>Patients without severe structural heart disease presenting with equal or more than 150 premature ventricular contractions per hour and/or non sustained ventricular tachycardia in drug-free holter monitoring were recruited in this double blind randomized active-controlled study. Eligible patients were randomly assigned to receive GFA or propafenone intravenously by a proportion of 1:1 in a double-blind manner. Intravenous bolus of the study medicine was given, followed by maintenance infusion for 6 hours. 24 hours continuous electrocardiographic recordings were performed to evaluate the efficacy. Vital signs, electrocardiograms and adverse events were documented before, during and after drug administration.</p><p><b>RESULTS</b>A total of 201 patients came from eight centres were randomized to GFA or propafenone group. The demographic characteristics, the extent of ventricular arrhythmias and baseline clinical findings were comparable between the two groups. There were no significant differences in the percentage of reducing premature ventricular contractions and the accumulated efficacy between two groups. GFA had tendency to be more effective than propafenone in reducing the number of ventricular ectopy (P = 0.0609). There were no significant differences in the onset of action after drug administration between two drugs. The tolerance of GFA was better than propafenone. The adverse events in GFA group were less severe than those in propafenone group.</p><p><b>CONCLUSIONS</b>Intravenous GFA in controlling the premature ventricular contraction has comparable effect to IV propafenone. Tolerance of GFA was better than propafenone.</p>

Process of human platelets loaded with rehalose before lyophilization / 中国实验血液学杂志

The aim of this research was to study the technology and methods of loading lyoprotectant-trehalose into cytoplasm of human platelets before lyophilization, to optimize experimental conditions of loading trehalose, to investigate the changes of platelets response to agonists and activation after incubation of platelets for 4 hours at 37 degrees C in the presence of lyoprotectant-trehalose, to protract the figures of loading efficiency and intracellular trehalose concentration versus incubation time, temperature and external trehalose concentration, to optimize loading parameters. The response of platelets to different agonists--thrombin, ADP, collagen and ristocetin were measured respectively by APACT2 aggregometer before and after loading trehalose into platelets; the expressions of CD62p and PAC-1 on platelet membranes in the presence and absence of reversible platelets activation inhibitors were measured by flow cytometry respectively before and after loading trehalose into cytoplasm of platelets. The results showed that the loading efficiency was linear to incubation time (2 hours later) and incubation temperature (rang from 30 degrees C to 40 degrees C), respectively. The loading efficiency almost reached 60% when the platelets were incubated at 37 degrees C for 4 hours. The intracellular trehalose concentration was higher with the increase of the extracellular trehalose concentration (< 50 mmol/L). Compared to untreated groups, the values of MPV and aggregation to different agonists in treated groups showed no significant difference, respectively (P > 0.01). After incubation of platelets for 4 hours, the expression of CD62p increased to some extent, however, the expression of CD62p decreased again when the reversible platelets activation inhibitor PGE-1 and adenosine were added to the incubation buffer. It is concluded that 37 degrees C, 4 hours and the extracellular trehalose concentration < 50 mmol/L are the optimal conditions for loading with trehalose. The processing of loading with trehalose before platelet lyophilization has no significant effects on response of platelets to agonists and activation.

Trehalose -- a biomembrane protectant applied to lyophilization of human red blood cells: review / 中国实验血液学杂志

Trehalose, as a nonreducing disaccharide, plays a role in protecting the cytoactivity when the cells is freezing, drying or lyophilization. It has been a biomembrane protectant applied to lyophilization of human blood cells (platelets and erythrocytes), and from which astonishing results have been obtained. Having powerful hydration, distinctive vitrification transform and crystal transform and unique resistance of high temperature and humidification, trehalose is thought of a preferred protectant in the study of cell preservation. In recent years, people concerned trehalose on its protective mechanism, experimental means of transit trehalose to mammal cells and the mechanism of loading in red blood cells. The above aspects were briefly summarized in this article.