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1.
J Integr Plant Biol ; 61(6): 749-764, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30387549

RESUMO

DNA methylation plays a crucial role in suppressing mobilization of transposable elements and regulation of gene expression. A number of studies have indicated that DNA methylation pathways and patterns exhibit distinct properties in different species, including Arabidopsis, rice, and maize. Here, we characterized the function of DDM1 in regulating genome-wide DNA methylation in maize. Two homologs of ZmDDM1 are abundantly expressed in the embryo and their simultaneous disruption caused embryo lethality with abnormalities in cell proliferation from the early stage of kernel development. We establish that ZmDDM1 is critical for DNA methylation, at CHG sites, and to a lesser extent at CG sites, in heterochromatic regions, and unexpectedly, it is required for the formation of m CHH islands. In addition, ZmDDM1 is indispensable for the presence of 24-nt siRNA, suggesting its involvement in the RdDM pathway. Our results provide novel insight into the role of ZmDDM1 in regulating the formation of m CHH islands, via the RdDM pathway maize, suggesting that, in comparison to Arabidopsis, maize may have adopted distinct mechanisms for regulating m CHH.


Assuntos
Metilação de DNA/genética , Proteínas de Plantas/metabolismo , Zea mays/genética , Genes de Plantas , Mutação com Perda de Função/genética , Fenótipo , Proteínas de Plantas/genética , RNA Interferente Pequeno/metabolismo , Sementes/embriologia , Sementes/genética , Zea mays/embriologia
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(4): 1204-1209, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30111431

RESUMO

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.


Assuntos
Coagulação Sanguínea , Testes de Coagulação Sanguínea , Transfusão de Sangue , Humanos , Tempo de Tromboplastina Parcial , Tempo de Protrombina
3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 25(3): 916-920, 2017 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-28641659

RESUMO

OBJECTIVE: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.


Assuntos
Sistema ABO de Grupos Sanguíneos , Transfusão de Sangue , Anticorpos , Teste de Coombs , Transfusão de Eritrócitos , Hemólise , Humanos , Lactente , Recém-Nascido , Estudos Retrospectivos
4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 24(4): 1226-31, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-27531805

RESUMO

OBJECTIVE: To explore the key technique for preparation of the frozen platelet and efficacy of its clinical application. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.


Assuntos
Plaquetas , Preservação de Sangue , Transfusão de Sangue , Congelamento , Hemostasia , Humanos , Contagem de Plaquetas , Transfusão de Plaquetas , Plaquetoferese , Reação Transfusional
5.
Chin J Nat Med ; 13(5): 361-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25986285

RESUMO

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.


Assuntos
Antiarrítmicos/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Bloqueadores dos Canais de Sódio/farmacologia , Análise de Variância , Animais , Relação Dose-Resposta a Droga , Feminino , Cobaias , Células HEK293 , Ventrículos do Coração/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Masculino , Potenciais da Membrana/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Técnicas de Patch-Clamp , Canais de Sódio/efeitos dos fármacos
6.
Fitoterapia ; 94: 120-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24508249

RESUMO

Two new diterpenoid alkaloids, Guan-Fu base J (GFJ, 1) and Guan-Fu base N (GFN, 2) along with nineteen known alkaloids (3-21) were isolated from the roots of Aconitum coreanum (Lèvl.) Rapaics, which is the raw material of a new approval anti-arrhythmia drug "Acehytisine Hydrochloride". The structures of isolated compounds were established by means of 1D, 2D NMR spectroscopic and chemical methods. All isolates obtained in the present study were evaluated for their inhibitory effects on blocking the ventricular specific sodium current using a whole-cell patch voltage-clamp technique. Among these 21 compounds, Guan-Fu base S (GFS, 3) showed the strongest inhibitory effect with an IC50 value of 3.48 µM, and only hetisine-type C20 diterpenoid alkaloids showed promising IC50 values for further development.


Assuntos
Aconitum/química , Alcaloides/química , Antiarrítmicos/química , Diterpenos/química , Extratos Vegetais/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Antiarrítmicos/isolamento & purificação , Antiarrítmicos/farmacologia , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Relação Dose-Resposta a Droga , Cobaias , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Masculino , Potenciais da Membrana/efeitos dos fármacos , Estrutura Molecular , Miócitos Cardíacos/efeitos dos fármacos , Técnicas de Patch-Clamp , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Sódio/fisiologia
7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(4): 1046-53, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23998610

RESUMO

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.


Assuntos
Plaquetas/efeitos dos fármacos , Ativação Plaquetária/efeitos dos fármacos , Glicoproteínas da Membrana de Plaquetas/metabolismo , S-Nitrosoglutationa/farmacologia , Preservação de Sangue/métodos , Congelamento , Humanos , Selectina-P/metabolismo , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 20(6): 1474-7, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23257456

RESUMO

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.


Assuntos
Membrana Eritrocítica/efeitos dos fármacos , Fragilidade Osmótica/efeitos dos fármacos , Trealose/farmacologia , Preservação de Sangue/métodos , Criopreservação/métodos , Eritrócitos/efeitos dos fármacos , Humanos
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 20(2): 386-9, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22541104

RESUMO

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.


Assuntos
Óxido Nítrico/metabolismo , Agregação Plaquetária/efeitos dos fármacos , S-Nitrosoglutationa/farmacologia , Plaquetas/efeitos dos fármacos , Congelamento , Humanos , Ativação Plaquetária/efeitos dos fármacos , Contagem de Plaquetas
10.
Bioorg Med Chem Lett ; 22(9): 3100-3, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22483610

RESUMO

Lipase-catalyzed acylation of Guanfu alcohol-amine (GFAA) with vinyl acetate (VA) was performed in non-aqueous system for the preparation of Guanfu base G (GFG), a plant-originated alkaloid with significant antiarrhythmic activity. Among the eight lipases from different origins, Novozym 435 was found to be the best biocatalyst. The most suitable molecular sieve amount, substrate concentration, molar ratio of VA to GFAA, enzyme amount and reaction temperature were proved to be 40 mg/mL, 6 µmol/mL, 10:1, 2mg/mL and 50 °C, respectively. A maximum GFG yield of 37.4% was achieved under the selected conditions with methanol served as the optimal reaction medium. The structure of the acetylated product was elucidated by (1)H NMR and (13)C NMR analysis.


Assuntos
Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Lipase/metabolismo , Acilação , Biocatálise , Metanol , Métodos , Estrutura Molecular , Compostos de Vinila/química
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 20(1): 224-8, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22391202

RESUMO

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.


Assuntos
Plaquetas , Preservação de Sangue/métodos , Criopreservação , Crioprotetores , Animais , Dimetil Sulfóxido , Cães , Humanos
12.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(9): 2055-8, 2010 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-20855248

RESUMO

OBJECTIVE: To investigate the different parameters of the lyophilization procedures that affect the recovery of the rehydrated red blood cells (RBCs). METHODS: 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. RESULTS: 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. CONCLUSION: 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.


Assuntos
Eritrócitos/citologia , Liofilização , Preservação de Tecido/métodos , Humanos
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 17(6): 1582-7, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20030952

RESUMO

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.


Assuntos
Preservação de Sangue/métodos , Eritrócitos , Liofilização/métodos , Contagem de Eritrócitos , Humanos , Soluções para Reidratação , Temperatura
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 17(5): 1368-72, 2009 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-19840486

RESUMO

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.


Assuntos
Crioprotetores/administração & dosagem , Crioprotetores/análise , Eritrócitos , Preservação de Sangue/métodos , Liofilização/métodos , Humanos , Trealose/administração & dosagem , Trealose/análise
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 16(4): 930-2, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-18718093

RESUMO

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.


Assuntos
Coagulação Sanguínea , Plaquetas/fisiologia , Preservação de Sangue , Criopreservação , Coagulação Sanguínea/fisiologia , Fatores de Coagulação Sanguínea/metabolismo , Criopreservação/métodos , Humanos , Complexo Glicoproteico GPIb-IX de Plaquetas/análise
16.
J Nat Prod ; 71(4): 674-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18303852

RESUMO

Five new lindenane sesquiterpene dimers ( 1- 5), named shizukaols K-O, and eight known sesquiterpene dimers were isolated from the roots of Chloranthus fortunei. The structures of 1- 5 were elucidated using spectroscopic data, mainly 1D NMR, 2D NMR, and mass spectra.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Magnoliopsida/química , Sesquiterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Sesquiterpenos/química
17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 15(5): 1079-83, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17956695

RESUMO

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.


Assuntos
Arginina/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Tetrazóis/farmacologia , Plaquetas/metabolismo , Cilostazol , Humanos , Selectina-P/efeitos dos fármacos , Selectina-P/metabolismo , Agregação Plaquetária/efeitos dos fármacos
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 15(5): 1098-101, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17956699

RESUMO

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.


Assuntos
Plaquetas , Preservação de Sangue/métodos , Liofilização/métodos , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Sobrevivência Celular , Humanos , Trealose/farmacologia
19.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 15(2): 412-6, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17493359

RESUMO

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.


Assuntos
Preservação de Sangue/métodos , Criopreservação/métodos , Crioprotetores , Eritrócitos , Trealose , Transporte Biológico Ativo/efeitos dos fármacos , Crioprotetores/metabolismo , Crioprotetores/farmacologia , Membrana Eritrocítica/metabolismo , Liofilização , Humanos , Fragilidade Osmótica , Temperatura , Fatores de Tempo , Trealose/metabolismo , Trealose/farmacologia
20.
Zhonghua Xin Xue Guan Bing Za Zhi ; 35(2): 151-4, 2007 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-17445412

RESUMO

OBJECTIVE: 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). METHODS: 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. RESULTS: 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). CONCLUSION: With the dosage used in the present study, the efficacy on terminating PSVT was comparable between AHH and PRO.


Assuntos
Antiarrítmicos/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Propafenona/uso terapêutico , Taquicardia Supraventricular/tratamento farmacológico , Adolescente , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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