BACKGROUND Coagulopathy and thromboembolic events are associated with poor outcomes in coronavirus disease 2019(COVID-19)patients.There is conflicting evidence on the effects of chronic anticoagulation on mortality an...BACKGROUND Coagulopathy and thromboembolic events are associated with poor outcomes in coronavirus disease 2019(COVID-19)patients.There is conflicting evidence on the effects of chronic anticoagulation on mortality and severity of COVID-19 disease.AIM To summarize the body of evidence on the effects of pre-hospital anticoagulation on outcomes in COVID-19 patients.METHODS A Literature search was performed on LitCovid PubMed,WHO,and Scopus databases from inception(December 2019)till June 2023 for original studies reporting an association between prior use of anticoagulants and patient outcomes in adults with COVID-19.The primary outcome was the risk of thromboembolic events in COVID-19 patients taking anticoagulants.Secondary outcomes included COVID-19 disease severity,in terms of intensive care unit admission or invasive mechanical ventilation/intubation requirement in patients hospitalized with COVID-19 infection,and mortality.The random effects models were used to calculate crude and adjusted odds ratios(aORs)with 95%confidence intervals(95%CIs).RESULTS Forty-six observational studies met our inclusion criteria.The unadjusted analysis found no association between prior anticoagulation and thromboembolic event risk[n=43851,9 studies,odds ratio(OR)=0.67(0.22,2.07);P=0.49;I2=95%].The association between prior anticoagulation and disease severity was non-significant[n=186782;22 studies,OR=1.08(0.78,1.49);P=0.64;I2=89%].However,pre-hospital anticoagulation significantly increased all-cause mortality risk[n=207292;35 studies,OR=1.72(1.37,2.17);P<0.00001;I2=93%].Pooling adjusted estimates revealed a statistically non-significant association between pre-hospital anticoagulation and thromboembolic event risk[aOR=0.87(0.42,1.80);P=0.71],mortality[aOR=0.94(0.84,1.05);P=0.31],and disease severity[aOR=0.96(0.72,1.26);P=0.76].CONCLUSION Prehospital anticoagulation was not significantly associated with reduced risk of thromboembolic events,improved survival,and lower disease severity in COVID-19 patients.展开更多
[Objective] To analyze the components and structure of Opuntia milpa alta polysaccharides, and to study its anticoagulant activity. [Method] The crude polysaccharides （CP） were prepared from Opuntia milpa alta using...[Objective] To analyze the components and structure of Opuntia milpa alta polysaccharides, and to study its anticoagulant activity. [Method] The crude polysaccharides （CP） were prepared from Opuntia milpa alta using hot water extraction and ethanol precipitation method, purified by anion-exchange chromatography and gel filtration chromatography to study its monosaccharide composition, weight-average molecular weight distribution and main chain structure. And a preliminary study was conducted on the anticoagulant activity of polysaccharide components. [Result] The polysaccharide components WSP1, WSP2a and WSP3 were obtained from CP by the anion-exchange chromatography and gel filtration chromatography. WSP1 was mainly composed of galactose with a weight-average molecular weight of 2.32×106. WSP2a consisted of rhamnose, arabinose, xylose, mannose, glucose, galactose, glucuronic acid and galacturonic acid, the contents were 6.3%, 32.3%, 12.9%, 1.5%, 4.8%, 37.1%, 0.64% and 4.4%, respectively. WSP3 mainly composed of arabinose, xylose, rhamnose and trace of glucose, mannose, uronic acid. The weight-average molecular weight of WSP2a and WSP3 was 1.24×106 and 7.92×106, respectively. WSP2 prolonged the activated partial thromboplatin time （APTT） and thrombin time （TT）, while had no significant effect on the prothrombin time （PT） in vitro, indicating that anticoagulant activity of WSP2 functions by affecting the intrinsic coagulation system. The test of inhibition to the conversion of fibrinogen into thrombin showed that WSP2a and WSP3 had obvious anticoagulant activity. Methylation analysis indicated that the main chain of WSP2a was constituted of 1, 4-GalA, 1, 2-Rha and 1, 2, 4-Rha. [Conclusion] This study provided experimental basis for the optimization and development of polysaccharide resources from cactus展开更多
In order to improve the anticoagulant function of Auricularia auricula, Auricularia auricula polysaccharide （AAP） was converted into its derivatives by the microbial fermentation method and then polysaccharide deriv...In order to improve the anticoagulant function of Auricularia auricula, Auricularia auricula polysaccharide （AAP） was converted into its derivatives by the microbial fermentation method and then polysaccharide derivatives with stronger anticoagulant activity were prepared. The optimal conditions for fermenting the polysaccharide from A. auricula were examined and the in vitro anticoagulant activities of transformed and untransformed polysaccharides were compared. Response surface tests and an orthogonal experiment indicated that the best conditions for microbial conversion of AAP3 were an AAP3 concentration of 4.0 mg/ mL, a ratio of substrate （AAP3 ） to donor （p-hydroxybenzoic acid） of 40：1, and a pH of 6.0. Bacillus subtilis Bs-07 was inoculated and then placed on a rotary shaker （ 120 r/min）, followed by fermentation for 48 h at 35 ℃. The conversion rate was found to be greater than 40%. The result of in vitro anticoagulant activity showed that the transformed polysaccharide improved activated partial thromboplastin time, prothrombin time, and thrombin time values and greatly enhanced anticoagulant activity compared to the untransformed polysaccharide.展开更多
Acute compartment syndrome(ACS) of the thigh following primary total hip arthroplasty(THA) is a highly uncommon complication and has not yet been reported before with regards to the anterior approach through the anter...Acute compartment syndrome(ACS) of the thigh following primary total hip arthroplasty(THA) is a highly uncommon complication and has not yet been reported before with regards to the anterior approach through the anterior supine interval. We present a case of a 69-year-old male patient with a history of stroke, who developed ACS of the thigh after elective THA while using therapeutic low molecular weight heparin as bridging for regular oral anticoagulation. ACS pathogenesis, diagnostic tools, treatment and relevant literature are discussed. The patient's ACS was recognized in time and treated by operative decompression with fasciotomy of the anterior compartment. Follow-up did not show any neurological deficit or soft-tissue damage.展开更多
Objectives To investigate the rate of anticoagulant use,the reasons for not prescribing anticoagulant,and the factors associated with non-prescription of anticoagulant in older Thai adults with non-valvular atrial fib...Objectives To investigate the rate of anticoagulant use,the reasons for not prescribing anticoagulant,and the factors associated with non-prescription of anticoagulant in older Thai adults with non-valvular atrial fibrillation.Methods A multicenter registry of patients with non-valvular atrial fibrillation was conducted during 2014 to 2017 in Thailand.Demographic,medical history,antithrombotic medication,non-antithrombotic medication,and laboratory data were collected and analyzed.Data were compared between the older adult (≥ 65 years) and younger adult (< 65 years) groups.The reasons why anticoagulant was not prescribed were collected,and predictive factors were identified.Results A total of 3218 patients (1873 males) with an average age of 67.3 ± 11.3 years were included.Almost two-thirds (61.0%) of patients were in the older adult group.Anticoagulant was prescribed in 2422 patients (75.3%): 81.4% in the older adult group and 65.7% in the younger adult group.The three main reasons for not prescribing anticoagulant were already taking antiplatelets,patient refusal,and bleeding risk.These reasons were more common in older adults as compared to younger adults.Multivariate analysis revealed current use of antiplatelets to be the most important factor that predict the non-prescription of anticoagulant in older population.Conclusions The prevalence of anticoagulant prescription among older Thai adults with atrial fibrillation is 81.4%.Taking antiplatelet drugs was found to be the strongest reason that predicts the non-prescription of anticoagulant in this patient population.A guideline should be developed to optimize the use of anticoagulant and antiplatelet in older adults.展开更多
The safety and efficacy of combined low dose aspirin and warfarin therapy in patients with atrial fibrillation after mechanical heart valve replacement were evaluated. A total of 1016 patients （620 females, mean age ...The safety and efficacy of combined low dose aspirin and warfarin therapy in patients with atrial fibrillation after mechanical heart valve replacement were evaluated. A total of 1016 patients （620 females, mean age of 36.8-4-7.7 years） admitted for cardiac valve replacement and complicated with atrial fibrillation after surgery were randomly divided into study （warfarin plus 75-100 mg aspirin） or control （warfarin only） groups. International normalized ratio （INR） and prothrombin time were main- tained at 1.8-2.5 and 1.5-2.0 times the normal values, respectively. Thromboembolic events and major bleedings were registered during the follow-up period. Patients were followed up for 24±9 months. The average dose of warfarin in the study and control groups was 2.91±0.83 mg and 2.88±0.76 mg, respec- tively （P〉0.05）. The incidence of overall thromboembolic events in study group was lower than that in control group （2.16% vs. 4.35%, P=0.049）. No statistically significant differences were found in hem- orrhage events （3.53% vs. 3.95%, P=-0.722） or mortality （0.20% vs. 0.40%, P=0.559） between the two groups. Combined low dose aspirin and warfarin therapy in the patients with atrial fibrillation following mechanical heart valve replacement significantly decreased thromboembolic events as compared with warfarin therapy alone. This combined treatment was not associated with an increase in the risk of major bleeding or mortality.展开更多
A rapid and sensitive method based on liquid chromatographtandem mass spectrometry （LC-MS/MS） for the determination of a novel anticoagulant peptide bivalirudin in human plasma has been developed and validated. Plas...A rapid and sensitive method based on liquid chromatographtandem mass spectrometry （LC-MS/MS） for the determination of a novel anticoagulant peptide bivalirudin in human plasma has been developed and validated. Plasma samples were precipitated protein with acetonitrile and reextracted with dichloromethane, after which the analyte and triptorelin as an internal standard （IS） were separated on a 300SB-Cl8 column （150 mm x 4.6 mm i.d., 5 gm particle size） using 0.1% formic acid：methanol （45：55, v/v） as mobile phase. The triple-quadrupole mass spectrometer, equipped with electrospray ionization （ESI） interface, was operated in the positive ion mode, and the multiplereaction monitoring （MRM） transitions of bivalirudin and IS were at m/z 1091.0-650.4 and m/z656.5 - 249.3, respectively. The lower limit of quantification （LLOQ） was 1 ng/mL for 100 ng/mL plasma sample and the assay was linear over the concentration range 1 1000 ng/mL. The accuracy was within a range from -0.4% to 0.5% in terms of relative error （RE） and the intra- and inter-day precisions in terms of relative standard deviation （RSD） were 〈2.92 and 〈 3.36, respectively. The method was successfully applied to a pharmacokinetic study involving intravenous administration of bivalirudin （0.5 mg/kg） to Chinese volunteers.展开更多
Background:Severe acute pancreatitis is a common diagnosis in emergency general surgery and can be a cause of significant morbidity and mortality.A consequence of severe acute pancreatitis is thrombus in the splanchni...Background:Severe acute pancreatitis is a common diagnosis in emergency general surgery and can be a cause of significant morbidity and mortality.A consequence of severe acute pancreatitis is thrombus in the splanchnic veins.These thrombi can potentially lead to bowel ischemia or hepatic failure.However,another complication of severe acute pancreatitis is retroperitoneal bleeding.At this time,it is unclear if treating patients for splanchnic vein thrombosis in the context of severe acute pancreatitis is associated with any outcome benefit.A systematic review might clarify this question.Data sources:A two-fold search strategy(one broad and one precise)looked at all published literature.The review was registered on PROSPERO(ID:CRD42018102705).MEDLINE,EMBASE,PubMed,Cochrane and Web of Science databases were searched and potentially relevant papers were reviewed indepen-dently by two researchers.Any disagreement was reviewed by a third independent researcher.Primary outcome was reestablishment of flow in the thrombosed vein versus bleeding complications.Results:Of 1462 papers assessed,a total of 16 papers were eligible for inclusion.There were no ran-domized controlled trials,2 were case series,5 retrospective single-center studies and 9 case reports.There were a total of 198 patients in these studies of whom 92(46.5%)received anticoagulation therapy.The rates of recanalization of veins in the treated and non-treated groups was 14%and 11%and bleeding complications were 16%and 5%,respectively.However,the included studies were too heterogeneous to undertake a meta-analysis.Conclusions:The systematic review highlights the lack evidence addressing this clinical question.There-fore a randomized controlled trial would be appropriate to undertake.展开更多
Sea cucumber is a traditional nutritional food and medicinal resource with many bioactive components in China. Holothuriafuscogliva is a big sea cucumber with a rich of bioactive polysaccharides. To investigate the bi...Sea cucumber is a traditional nutritional food and medicinal resource with many bioactive components in China. Holothuriafuscogliva is a big sea cucumber with a rich of bioactive polysaccharides. To investigate the bioactivities of the polysaccharides from sea cucumber H. fuscogliva, we prepared the sulfated polysaccharides （HfP） from sea cucumber H. fuscogliva using a protease hydrolysis method. Antioxidant activities of HfP were investigated, including hydroxyl radical scavenging activity and superoxide radical scavenging activity. And, the anticoagulant activities of HfP were studied, including the activated partial thromboplastin time （APTT）, prothrombin time （PT） and thrombin time （TT）. The average molecular weight was 1 867.1 Da, with a sulfate content of 20.7%. In addition, the molar ratio of monosaccharide composition of HfP was Man： Rha： Glc A： Glc： Gal： Xyl： Fuc=0.083 6： 0.437： 0.134： 0： 1.182： 0.748： 1. It had a strong antioxidant activity, the hydroxyl and superoxide radical scavenging activity ECs0 of HfP was 3.74 and 0.037 mg/mL, respectively. It also showed a good anticoagulant activity in our study. The APTT of HfP was much higher than that of heparin sodium, and the PT and TT of HfP was close to that ofheparin sodium at a low concentration. Therefore, HfP shows a good antioxidant and anticoagulant activity and it may become a potential candidate of the natural antioxidant and anticoagulant and will have a good application future in health product or medicine industry.展开更多
Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, ...Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, phosphorylated, and aminated fucoidan) was examined using in-vitro anticoagulant systems. The correlation between chemical variations within the fucoidan group and anticoagulant activity was determined. The in-vitro anticoagulant properties of fucoidan and its derivatives were determined by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). The results indicate anticoagulant activity in all samples using APTT and TT assays; however, only the fucoidan derivatives affected the PT assay. Thus, the fucoidan derivatives were able to inhibit both intrinsic and extrinsic blood coagulants. Fucoidan (FPS) and its derivatives presented better anticoagulant activity than low molecular weight fucoidan (DFPS) and its derivatives, suggesting that molecular weight and proper conformation are contributing factors for anticoagulant activity of polysaccharides. Amino groups have a positive charge and can thus change the charge density of fucoidan. Accordingly, among the tested samples, aminated fucoidan (NF) was the most active reflecting the importance of charge density for anticoagulant activity. Available data obtained using in-vitro models suggest that the sulfate content, sulfate/total-sugar ratio, molecular weight, and the substituted group of fucoidan are important factors for anticoagulant activity but that the influence of sulfate, phosphate and amino groups on anticoagulant activity was different.展开更多
Heparin has been used as an anticoagulant drug for many years, but it has significant side ef fects. In the search for good substitutes, low molecular weight(MW) polysaccharides from S argassum fusiforme have been exa...Heparin has been used as an anticoagulant drug for many years, but it has significant side ef fects. In the search for good substitutes, low molecular weight(MW) polysaccharides from S argassum fusiforme have been examined and confi rmed to possess biological activities. Here, S. fusiforme polysaccharides(SFP) were extracted and subjected to a hydrogen peroxide(H_2O_2) oxidation method for the preparation of low-MW SFP(LSFP). The effects of temperature, pH, and H_2O_2 concentration on the degradation process were also examined. Several LSFP of 36, 9, 5.7, and 2.7 kDa were obtained under different conditions, and their anticoagulant activities studied in vitro. The results showed that SFP and LSFP prolonged activated partial thromboplastin(APTT), prothrombin(PT) and thrombin times(TT) significantly, indicating that these low MW polysaccharides possessed anticoagulant activity in the intrinsic, extrinsic, and common coagulation pathways. As these ef fects were related to the MW of the polysaccharides in APTT and TT but not in PT, the contents of the monosaccharide fucose and sulfate and the polysaccharide MW could have exerted combined ef fects. The details of this mechanism require further verifi cation.展开更多
文摘BACKGROUND Coagulopathy and thromboembolic events are associated with poor outcomes in coronavirus disease 2019(COVID-19)patients.There is conflicting evidence on the effects of chronic anticoagulation on mortality and severity of COVID-19 disease.AIM To summarize the body of evidence on the effects of pre-hospital anticoagulation on outcomes in COVID-19 patients.METHODS A Literature search was performed on LitCovid PubMed,WHO,and Scopus databases from inception(December 2019)till June 2023 for original studies reporting an association between prior use of anticoagulants and patient outcomes in adults with COVID-19.The primary outcome was the risk of thromboembolic events in COVID-19 patients taking anticoagulants.Secondary outcomes included COVID-19 disease severity,in terms of intensive care unit admission or invasive mechanical ventilation/intubation requirement in patients hospitalized with COVID-19 infection,and mortality.The random effects models were used to calculate crude and adjusted odds ratios(aORs)with 95%confidence intervals(95%CIs).RESULTS Forty-six observational studies met our inclusion criteria.The unadjusted analysis found no association between prior anticoagulation and thromboembolic event risk[n=43851,9 studies,odds ratio(OR)=0.67(0.22,2.07);P=0.49;I2=95%].The association between prior anticoagulation and disease severity was non-significant[n=186782;22 studies,OR=1.08(0.78,1.49);P=0.64;I2=89%].However,pre-hospital anticoagulation significantly increased all-cause mortality risk[n=207292;35 studies,OR=1.72(1.37,2.17);P<0.00001;I2=93%].Pooling adjusted estimates revealed a statistically non-significant association between pre-hospital anticoagulation and thromboembolic event risk[aOR=0.87(0.42,1.80);P=0.71],mortality[aOR=0.94(0.84,1.05);P=0.31],and disease severity[aOR=0.96(0.72,1.26);P=0.76].CONCLUSION Prehospital anticoagulation was not significantly associated with reduced risk of thromboembolic events,improved survival,and lower disease severity in COVID-19 patients.
基金Supported by the National Natural Science Foundation of China(31173753)the International Scientific and Technological Cooperation Project of Anhui Province(10080703035)~~
文摘[Objective] To analyze the components and structure of Opuntia milpa alta polysaccharides, and to study its anticoagulant activity. [Method] The crude polysaccharides （CP） were prepared from Opuntia milpa alta using hot water extraction and ethanol precipitation method, purified by anion-exchange chromatography and gel filtration chromatography to study its monosaccharide composition, weight-average molecular weight distribution and main chain structure. And a preliminary study was conducted on the anticoagulant activity of polysaccharide components. [Result] The polysaccharide components WSP1, WSP2a and WSP3 were obtained from CP by the anion-exchange chromatography and gel filtration chromatography. WSP1 was mainly composed of galactose with a weight-average molecular weight of 2.32×106. WSP2a consisted of rhamnose, arabinose, xylose, mannose, glucose, galactose, glucuronic acid and galacturonic acid, the contents were 6.3%, 32.3%, 12.9%, 1.5%, 4.8%, 37.1%, 0.64% and 4.4%, respectively. WSP3 mainly composed of arabinose, xylose, rhamnose and trace of glucose, mannose, uronic acid. The weight-average molecular weight of WSP2a and WSP3 was 1.24×106 and 7.92×106, respectively. WSP2 prolonged the activated partial thromboplatin time （APTT） and thrombin time （TT）, while had no significant effect on the prothrombin time （PT） in vitro, indicating that anticoagulant activity of WSP2 functions by affecting the intrinsic coagulation system. The test of inhibition to the conversion of fibrinogen into thrombin showed that WSP2a and WSP3 had obvious anticoagulant activity. Methylation analysis indicated that the main chain of WSP2a was constituted of 1, 4-GalA, 1, 2-Rha and 1, 2, 4-Rha. [Conclusion] This study provided experimental basis for the optimization and development of polysaccharide resources from cactus
基金Heilongjiang Province Application Technology Research and Development Plan(No.GA13B202)Heilongjiang Postdoctoral Foundation(No.LBH-Z13008)
文摘In order to improve the anticoagulant function of Auricularia auricula, Auricularia auricula polysaccharide （AAP） was converted into its derivatives by the microbial fermentation method and then polysaccharide derivatives with stronger anticoagulant activity were prepared. The optimal conditions for fermenting the polysaccharide from A. auricula were examined and the in vitro anticoagulant activities of transformed and untransformed polysaccharides were compared. Response surface tests and an orthogonal experiment indicated that the best conditions for microbial conversion of AAP3 were an AAP3 concentration of 4.0 mg/ mL, a ratio of substrate （AAP3 ） to donor （p-hydroxybenzoic acid） of 40：1, and a pH of 6.0. Bacillus subtilis Bs-07 was inoculated and then placed on a rotary shaker （ 120 r/min）, followed by fermentation for 48 h at 35 ℃. The conversion rate was found to be greater than 40%. The result of in vitro anticoagulant activity showed that the transformed polysaccharide improved activated partial thromboplastin time, prothrombin time, and thrombin time values and greatly enhanced anticoagulant activity compared to the untransformed polysaccharide.
文摘Acute compartment syndrome(ACS) of the thigh following primary total hip arthroplasty(THA) is a highly uncommon complication and has not yet been reported before with regards to the anterior approach through the anterior supine interval. We present a case of a 69-year-old male patient with a history of stroke, who developed ACS of the thigh after elective THA while using therapeutic low molecular weight heparin as bridging for regular oral anticoagulation. ACS pathogenesis, diagnostic tools, treatment and relevant literature are discussed. The patient's ACS was recognized in time and treated by operative decompression with fasciotomy of the anterior compartment. Follow-up did not show any neurological deficit or soft-tissue damage.
基金funded by the Health Systems Research Institute (HSRI), Nonthaburi, Thailand (grant no. 59-053)the Heart Association of Thailand under the Royal Patronage of H.M. the King, Bangkok, ThailandThe Royal College of Physicians of Thailand, Bangkok, Thailand
文摘Objectives To investigate the rate of anticoagulant use,the reasons for not prescribing anticoagulant,and the factors associated with non-prescription of anticoagulant in older Thai adults with non-valvular atrial fibrillation.Methods A multicenter registry of patients with non-valvular atrial fibrillation was conducted during 2014 to 2017 in Thailand.Demographic,medical history,antithrombotic medication,non-antithrombotic medication,and laboratory data were collected and analyzed.Data were compared between the older adult (≥ 65 years) and younger adult (< 65 years) groups.The reasons why anticoagulant was not prescribed were collected,and predictive factors were identified.Results A total of 3218 patients (1873 males) with an average age of 67.3 ± 11.3 years were included.Almost two-thirds (61.0%) of patients were in the older adult group.Anticoagulant was prescribed in 2422 patients (75.3%): 81.4% in the older adult group and 65.7% in the younger adult group.The three main reasons for not prescribing anticoagulant were already taking antiplatelets,patient refusal,and bleeding risk.These reasons were more common in older adults as compared to younger adults.Multivariate analysis revealed current use of antiplatelets to be the most important factor that predict the non-prescription of anticoagulant in older population.Conclusions The prevalence of anticoagulant prescription among older Thai adults with atrial fibrillation is 81.4%.Taking antiplatelet drugs was found to be the strongest reason that predicts the non-prescription of anticoagulant in this patient population.A guideline should be developed to optimize the use of anticoagulant and antiplatelet in older adults.
文摘The safety and efficacy of combined low dose aspirin and warfarin therapy in patients with atrial fibrillation after mechanical heart valve replacement were evaluated. A total of 1016 patients （620 females, mean age of 36.8-4-7.7 years） admitted for cardiac valve replacement and complicated with atrial fibrillation after surgery were randomly divided into study （warfarin plus 75-100 mg aspirin） or control （warfarin only） groups. International normalized ratio （INR） and prothrombin time were main- tained at 1.8-2.5 and 1.5-2.0 times the normal values, respectively. Thromboembolic events and major bleedings were registered during the follow-up period. Patients were followed up for 24±9 months. The average dose of warfarin in the study and control groups was 2.91±0.83 mg and 2.88±0.76 mg, respec- tively （P〉0.05）. The incidence of overall thromboembolic events in study group was lower than that in control group （2.16% vs. 4.35%, P=0.049）. No statistically significant differences were found in hem- orrhage events （3.53% vs. 3.95%, P=-0.722） or mortality （0.20% vs. 0.40%, P=0.559） between the two groups. Combined low dose aspirin and warfarin therapy in the patients with atrial fibrillation following mechanical heart valve replacement significantly decreased thromboembolic events as compared with warfarin therapy alone. This combined treatment was not associated with an increase in the risk of major bleeding or mortality.
基金the National Natural Science Foundation (30973587)the China Postdoctoral Science Foundation (20110491328)the National Natural Science Funds for Young Scholar (81102383)for financial support
文摘A rapid and sensitive method based on liquid chromatographtandem mass spectrometry （LC-MS/MS） for the determination of a novel anticoagulant peptide bivalirudin in human plasma has been developed and validated. Plasma samples were precipitated protein with acetonitrile and reextracted with dichloromethane, after which the analyte and triptorelin as an internal standard （IS） were separated on a 300SB-Cl8 column （150 mm x 4.6 mm i.d., 5 gm particle size） using 0.1% formic acid：methanol （45：55, v/v） as mobile phase. The triple-quadrupole mass spectrometer, equipped with electrospray ionization （ESI） interface, was operated in the positive ion mode, and the multiplereaction monitoring （MRM） transitions of bivalirudin and IS were at m/z 1091.0-650.4 and m/z656.5 - 249.3, respectively. The lower limit of quantification （LLOQ） was 1 ng/mL for 100 ng/mL plasma sample and the assay was linear over the concentration range 1 1000 ng/mL. The accuracy was within a range from -0.4% to 0.5% in terms of relative error （RE） and the intra- and inter-day precisions in terms of relative standard deviation （RSD） were 〈2.92 and 〈 3.36, respectively. The method was successfully applied to a pharmacokinetic study involving intravenous administration of bivalirudin （0.5 mg/kg） to Chinese volunteers.
文摘Background:Severe acute pancreatitis is a common diagnosis in emergency general surgery and can be a cause of significant morbidity and mortality.A consequence of severe acute pancreatitis is thrombus in the splanchnic veins.These thrombi can potentially lead to bowel ischemia or hepatic failure.However,another complication of severe acute pancreatitis is retroperitoneal bleeding.At this time,it is unclear if treating patients for splanchnic vein thrombosis in the context of severe acute pancreatitis is associated with any outcome benefit.A systematic review might clarify this question.Data sources:A two-fold search strategy(one broad and one precise)looked at all published literature.The review was registered on PROSPERO(ID:CRD42018102705).MEDLINE,EMBASE,PubMed,Cochrane and Web of Science databases were searched and potentially relevant papers were reviewed indepen-dently by two researchers.Any disagreement was reviewed by a third independent researcher.Primary outcome was reestablishment of flow in the thrombosed vein versus bleeding complications.Results:Of 1462 papers assessed,a total of 16 papers were eligible for inclusion.There were no ran-domized controlled trials,2 were case series,5 retrospective single-center studies and 9 case reports.There were a total of 198 patients in these studies of whom 92(46.5%)received anticoagulation therapy.The rates of recanalization of veins in the treated and non-treated groups was 14%and 11%and bleeding complications were 16%and 5%,respectively.However,the included studies were too heterogeneous to undertake a meta-analysis.Conclusions:The systematic review highlights the lack evidence addressing this clinical question.There-fore a randomized controlled trial would be appropriate to undertake.
基金Supported by the Science and Technology Service Network Program of Chinese Academy of Sciences(No.KFJ-EW-STS-060)the National Special Research Fund for Non-Profit Marine Sector(No.201405038-2)+1 种基金the Scientific and Technological Innovation ProjectFinancially Supported by Qingdao National Laboratory for Marine Science and Technology(No.2015ASKJ02)
文摘Sea cucumber is a traditional nutritional food and medicinal resource with many bioactive components in China. Holothuriafuscogliva is a big sea cucumber with a rich of bioactive polysaccharides. To investigate the bioactivities of the polysaccharides from sea cucumber H. fuscogliva, we prepared the sulfated polysaccharides （HfP） from sea cucumber H. fuscogliva using a protease hydrolysis method. Antioxidant activities of HfP were investigated, including hydroxyl radical scavenging activity and superoxide radical scavenging activity. And, the anticoagulant activities of HfP were studied, including the activated partial thromboplastin time （APTT）, prothrombin time （PT） and thrombin time （TT）. The average molecular weight was 1 867.1 Da, with a sulfate content of 20.7%. In addition, the molar ratio of monosaccharide composition of HfP was Man： Rha： Glc A： Glc： Gal： Xyl： Fuc=0.083 6： 0.437： 0.134： 0： 1.182： 0.748： 1. It had a strong antioxidant activity, the hydroxyl and superoxide radical scavenging activity ECs0 of HfP was 3.74 and 0.037 mg/mL, respectively. It also showed a good anticoagulant activity in our study. The APTT of HfP was much higher than that of heparin sodium, and the PT and TT of HfP was close to that ofheparin sodium at a low concentration. Therefore, HfP shows a good antioxidant and anticoagulant activity and it may become a potential candidate of the natural antioxidant and anticoagulant and will have a good application future in health product or medicine industry.
基金Supported by the Ocean Public Welfare Scientific Research Project, State Oceanic Administration of the People's Republic of China (No. 201005024)
文摘Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, phosphorylated, and aminated fucoidan) was examined using in-vitro anticoagulant systems. The correlation between chemical variations within the fucoidan group and anticoagulant activity was determined. The in-vitro anticoagulant properties of fucoidan and its derivatives were determined by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). The results indicate anticoagulant activity in all samples using APTT and TT assays; however, only the fucoidan derivatives affected the PT assay. Thus, the fucoidan derivatives were able to inhibit both intrinsic and extrinsic blood coagulants. Fucoidan (FPS) and its derivatives presented better anticoagulant activity than low molecular weight fucoidan (DFPS) and its derivatives, suggesting that molecular weight and proper conformation are contributing factors for anticoagulant activity of polysaccharides. Amino groups have a positive charge and can thus change the charge density of fucoidan. Accordingly, among the tested samples, aminated fucoidan (NF) was the most active reflecting the importance of charge density for anticoagulant activity. Available data obtained using in-vitro models suggest that the sulfate content, sulfate/total-sugar ratio, molecular weight, and the substituted group of fucoidan are important factors for anticoagulant activity but that the influence of sulfate, phosphate and amino groups on anticoagulant activity was different.
基金Supported by the Ocean Public Welfare Scientifi c Research Project,State Oceanic Administration of the People’s Republic of China(No.201505033)the Qingdao People’s Livelihood Science and Technology Program(No.16-6-2-41-nsh)
文摘Heparin has been used as an anticoagulant drug for many years, but it has significant side ef fects. In the search for good substitutes, low molecular weight(MW) polysaccharides from S argassum fusiforme have been examined and confi rmed to possess biological activities. Here, S. fusiforme polysaccharides(SFP) were extracted and subjected to a hydrogen peroxide(H_2O_2) oxidation method for the preparation of low-MW SFP(LSFP). The effects of temperature, pH, and H_2O_2 concentration on the degradation process were also examined. Several LSFP of 36, 9, 5.7, and 2.7 kDa were obtained under different conditions, and their anticoagulant activities studied in vitro. The results showed that SFP and LSFP prolonged activated partial thromboplastin(APTT), prothrombin(PT) and thrombin times(TT) significantly, indicating that these low MW polysaccharides possessed anticoagulant activity in the intrinsic, extrinsic, and common coagulation pathways. As these ef fects were related to the MW of the polysaccharides in APTT and TT but not in PT, the contents of the monosaccharide fucose and sulfate and the polysaccharide MW could have exerted combined ef fects. The details of this mechanism require further verifi cation.
