Alkali metal DC arc discharge has the characteristics of easy ionization,low power consumption,high plasma temperature and ionization degree,etc,which can be applied in aerospace vehicles in various ways.In this paper...Alkali metal DC arc discharge has the characteristics of easy ionization,low power consumption,high plasma temperature and ionization degree,etc,which can be applied in aerospace vehicles in various ways.In this paper,we calculate the physical property parameters of lithium vapor,one of the major alkali metals,and analyze the discharge characteristics of lithium plasma with the magnetohydrodynamic(MHD)model.The discharge effects between constant current and voltage sources are also compared.It is shown that the lithium plasma of DC arc discharge has relatively high temperature and current density.The peak temperature can reach tens of thousands of K,and the current density reaches 6 x 107 A m 2.Under the same rated power,the plasma parameters of the constant voltage source discharge are much higher than those of the constant current source discharge,which can be used as the preferred discharge mode for aerospace applications.展开更多
Importance:Tertiary prophylaxis using a low-dose regimen is usually insufficient to prevent recurrent joint bleeding and deterioration in joint diseases in children with severe hemophilia A.Pharmacokinetic(PK)dosing i...Importance:Tertiary prophylaxis using a low-dose regimen is usually insufficient to prevent recurrent joint bleeding and deterioration in joint diseases in children with severe hemophilia A.Pharmacokinetic(PK)dosing is a useful approach to increase the precision and efficiency of prophylaxis.Objective:To explore the efficacy of PK-tailored tertiary prophylaxis in children with severe hemophilia A.Methods:We implemented a PK-tailored tertiary prophylaxis program for 15 boys with severe hemophilia A aged 5-16 years at Beijing Children’s Hospital.Following PK testing and a 6-month evaluation period(phase I),15 patients were divided in two groups according to individual PK data and actual bleeding:(1)a PK-tailored group[modified prophylaxis regimen according to PK data for the next 6 months(phase II);n=8]and(2)a maintenance group(continued the original regimen for the next 6 months;n=7).We compared the bleeding rate,infusion frequency,and factor VIII(FVIII)consumption between the two groups.results:In the PK-tailored group,the median annual joint bleeding rate was reduced from 7.8 in phase I to 1.4 in phase II,mean annual total factor consumption increased from 1619.0 IU/kg in phase I to 2401.9 IU/kg in phase II,and median infusion frequency for prophylaxis increased from 104 times/year in phase I to 156 times/year in phase II(P<0.05).Although the FVIII consumption increased,it remained at approximately half of the standard method.Interpretation:PK-tailored prophylaxis may represent a more efficient approach to individual prophylaxis in China,but further studies are required to verify this.展开更多
Importance: Joint disease affects more than 90% of severe hemophiliacs. Early diagnosis is critical in preventing hemophilic arthritis. Magnetic resonance imaging (MRI) enables visualization of early arthropathic chan...Importance: Joint disease affects more than 90% of severe hemophiliacs. Early diagnosis is critical in preventing hemophilic arthritis. Magnetic resonance imaging (MRI) enables visualization of early arthropathic changes and plays an important role in treatment. Objective: To evaluate the role of T2 mapping in detecting early cartilage lesions in the knee and ankle joints of children with hemophilic arthropathy. Methods: Target joints of 15 male patients with clinically confirmed moderate or severe hemophilia were evaluated with MRI. In addition to routine MRI protocols (T1WI, T2_FFE, T2_SPAIR, PDW_TSE), T2 mapping was used to evaluate the articular cartilage of target joints. results: The mean T2 value of the distal femoral cartilage was 46.72 ± 10.94 ms, which is higher than the reported age-matched normal value (40.27 ± 3.50 ms). The mean T2 value of the proximal tibial cartilage was 45.60 ± 8.82 ms, which is higher than the reported normal value (31.15 ± 1.86 ms). Four examined joints (two ankles, two knees) showed normal morphology with no abnormal signal on routine MR sequences. However, T2 mapping showed locally increased T2 values in the cartilage, along with uneven color scales. Interpretation: The quantitative assessment method of T2 mapping might be helpful to early diagnosis for articular cartilage lesions. It might be a potential tool for early assessment of cartilage changes and quantification of lesion's severity for hemophilia joint.展开更多
INTRODUCTION The phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit delta gene (PIK3CD), associated with primary immunodeficiency disease (PID), encodes the p110δ catalytic subunit and is predominantly...INTRODUCTION The phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit delta gene (PIK3CD), associated with primary immunodeficiency disease (PID), encodes the p110δ catalytic subunit and is predominantly expressed in immune cells such as lymphocytes.展开更多
Importance: Immune thrombocytopenic purpura (ITP) is the most common bleeding disorder in children. Despite the highly spontaneously remission, still almost 20% of cases progress into chronic or refractory ITP, which ...Importance: Immune thrombocytopenic purpura (ITP) is the most common bleeding disorder in children. Despite the highly spontaneously remission, still almost 20% of cases progress into chronic or refractory ITP, which seriously affects children's quality of life. Currently there is no method to predict the initial stage of childhood ITP. Objectives: To evaluate platelet-specific antibodies and compare differences in their expression in childhood ITP to predict clinical progression. Methods: This is a single-center prospective cohort study from April 2014 to October 2015. We enrolled children initially diagnosed as ITP. Anti-GPIIb/IIIa and GPIb/IX antibodies were assayed by enzyme-linked immunoadsorbent assay (ELISA) and patients were followed up for 1 year. We also analyzed the relationship between the expression of the platelet-specific antibodies GPIIb/IIIa and GPIb/IX and their respective clinical prognoses. results: Overall, 134 cases were enrolled including 77 boys and 57 girls with a median age of 19 months (range: 1 to 159). Positive rates of anti-platelet antibodies were 79.8%. After a 1-year observation period, 84.3%were diagnosed as newly diagnosed ITP and 13.4% were diagnosed as chronic ITP. Patients with anti-GPIIb/IIIa antibody had a higher risk for newly diagnosed ITP compared with patients who were anti-GPIb/IX antibody positive only (93% vs 25%, P = 0.005;87% vs 25%, P = 0.014, respectively). There were more anti-GPIb/IX antibody positive only cases, diagnosed as chronic ITP, compared with anti-GPIIb/IIIa antibody positive only cases and double GPIIb/IIIa and GPIb/IX antibody positive cases (75% vs 7%, P = 0.005;75% vs 13%, P = 0.014, respectively). Interpretation: Patients with anti-GPIIb/IIIa antibody (either single or double) were predicted to have a good prognosis, whereas anti-GPIb/IX antibody only predicted a poor prognosis. These results should be confirmed via a larger cohort multicenter study.展开更多
INTRODUCTION Primary immune thrombocytopenia(ITP)of childhood is an acquired,immune-mediated,bleeding disorder charac-terized by an isolated platelet counts decreased without an identifed cause during childhood.1 The ...INTRODUCTION Primary immune thrombocytopenia(ITP)of childhood is an acquired,immune-mediated,bleeding disorder charac-terized by an isolated platelet counts decreased without an identifed cause during childhood.1 The main pathogenesis is loss of immune tolerance,which leads to immune-mediated platelet destruction and/or suppression of platelet production.展开更多
Over the last few decades,a plethora of guidelines for primary immune thromboeytopenia(ITP)in children have been developed and published.However,the guidelines developed by one country or organization are not always a...Over the last few decades,a plethora of guidelines for primary immune thromboeytopenia(ITP)in children have been developed and published.However,the guidelines developed by one country or organization are not always appropriate to other countries or regions due to differences in local circumstances.展开更多
Importance:The use of factor VIII(FVIII)concentrates under pharmacokinetic(PK)guidance has become the main approach for treatment of hemophilia.However,limited PK research has been conducted in Chinese pediatric patie...Importance:The use of factor VIII(FVIII)concentrates under pharmacokinetic(PK)guidance has become the main approach for treatment of hemophilia.However,limited PK research has been conducted in Chinese pediatric patients.Objective:To investigate the PK parameters of various FVIII concentrates in Chinese pediatric patients.Methods:Seventy-nine patients were enrolled(28 treated with Kogenate FS^(®),23 treated with Advate^(®),and 28 treated with GreenMono^(™)).All enrolled patients participated in single-dose PK analysis after at least a 3-day washout period.Blood samples were collected predose,as well as at 1 h,9 h,24 h,and 48 h after infusion;FVIII levels were measured using a one-stage clotting assay,von Willebrand Factor Antigen(VWF:Ag)levels and blood types were also determined.PK parameters were evaluated by WAPPS-Hemo.Results:Mean values of terminal elimination half-life time(t_(1/2))for the Kogenate FS^(®),Advate^(®),and GreenMono^(™)FVIII groups were 12.24 h,10.18 h,and 9.62 h;median clearance values were 4.16,6.23,and 5.11 mL kg^(-1)h^(-1);and median in vivo recovery values were 1.97,1.55,and 1.61 IU/dL per IU/kg.Longer t_(1/2),higher in vivo recovery,and lower clearance were observed in patients with higher VWF:Ag level who were treated with recombinant concentrates.Interpretation:Chinese pediatric patients with hemophilia had FVIII PK characteristics similar to those previously observed in non-Chinese children,including large variation among individuals.VWF:Ag level and FVIII brand were associated with differences in FVIII PK.Thus,PK-guided dosing should be used to optimize individualized therapy in Chinese children.展开更多
INTRODUCTION
Congenital neutropenia (CN) is a rare primary immunodeficiency disease that includes severe congenital neutropenia (SCN) as a major subtype. SCN was first described in 1956 by Rolf Kostmann, and is chara...INTRODUCTION
Congenital neutropenia (CN) is a rare primary immunodeficiency disease that includes severe congenital neutropenia (SCN) as a major subtype. SCN was first described in 1956 by Rolf Kostmann, and is characterized by an absolute neutrophil count (ANC) of <0.5×109/L. SCN patients can also develop acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS).1 In this study, we report two pediatric patients from one family with SCN associated with the neutrophil elastase gene (ELANE).展开更多
文摘Alkali metal DC arc discharge has the characteristics of easy ionization,low power consumption,high plasma temperature and ionization degree,etc,which can be applied in aerospace vehicles in various ways.In this paper,we calculate the physical property parameters of lithium vapor,one of the major alkali metals,and analyze the discharge characteristics of lithium plasma with the magnetohydrodynamic(MHD)model.The discharge effects between constant current and voltage sources are also compared.It is shown that the lithium plasma of DC arc discharge has relatively high temperature and current density.The peak temperature can reach tens of thousands of K,and the current density reaches 6 x 107 A m 2.Under the same rated power,the plasma parameters of the constant voltage source discharge are much higher than those of the constant current source discharge,which can be used as the preferred discharge mode for aerospace applications.
文摘Importance:Tertiary prophylaxis using a low-dose regimen is usually insufficient to prevent recurrent joint bleeding and deterioration in joint diseases in children with severe hemophilia A.Pharmacokinetic(PK)dosing is a useful approach to increase the precision and efficiency of prophylaxis.Objective:To explore the efficacy of PK-tailored tertiary prophylaxis in children with severe hemophilia A.Methods:We implemented a PK-tailored tertiary prophylaxis program for 15 boys with severe hemophilia A aged 5-16 years at Beijing Children’s Hospital.Following PK testing and a 6-month evaluation period(phase I),15 patients were divided in two groups according to individual PK data and actual bleeding:(1)a PK-tailored group[modified prophylaxis regimen according to PK data for the next 6 months(phase II);n=8]and(2)a maintenance group(continued the original regimen for the next 6 months;n=7).We compared the bleeding rate,infusion frequency,and factor VIII(FVIII)consumption between the two groups.results:In the PK-tailored group,the median annual joint bleeding rate was reduced from 7.8 in phase I to 1.4 in phase II,mean annual total factor consumption increased from 1619.0 IU/kg in phase I to 2401.9 IU/kg in phase II,and median infusion frequency for prophylaxis increased from 104 times/year in phase I to 156 times/year in phase II(P<0.05).Although the FVIII consumption increased,it remained at approximately half of the standard method.Interpretation:PK-tailored prophylaxis may represent a more efficient approach to individual prophylaxis in China,but further studies are required to verify this.
文摘Importance: Joint disease affects more than 90% of severe hemophiliacs. Early diagnosis is critical in preventing hemophilic arthritis. Magnetic resonance imaging (MRI) enables visualization of early arthropathic changes and plays an important role in treatment. Objective: To evaluate the role of T2 mapping in detecting early cartilage lesions in the knee and ankle joints of children with hemophilic arthropathy. Methods: Target joints of 15 male patients with clinically confirmed moderate or severe hemophilia were evaluated with MRI. In addition to routine MRI protocols (T1WI, T2_FFE, T2_SPAIR, PDW_TSE), T2 mapping was used to evaluate the articular cartilage of target joints. results: The mean T2 value of the distal femoral cartilage was 46.72 ± 10.94 ms, which is higher than the reported age-matched normal value (40.27 ± 3.50 ms). The mean T2 value of the proximal tibial cartilage was 45.60 ± 8.82 ms, which is higher than the reported normal value (31.15 ± 1.86 ms). Four examined joints (two ankles, two knees) showed normal morphology with no abnormal signal on routine MR sequences. However, T2 mapping showed locally increased T2 values in the cartilage, along with uneven color scales. Interpretation: The quantitative assessment method of T2 mapping might be helpful to early diagnosis for articular cartilage lesions. It might be a potential tool for early assessment of cartilage changes and quantification of lesion's severity for hemophilia joint.
基金Special Fund of the Pediatric Medical Coordinated Development Center of Beijing Municipal Administration(XTZD20180202)Beijing Municipal Science and Technology Commission(Z171100001017050)+1 种基金Scientific Research Common Program of Beijing Municipal Commission of Education(KM201710025019)Talent Training Project-Fostering Fund of National Natural Science Foundation of Beijing Children's Hospital,Capital Medical University(GPY201713).
文摘INTRODUCTION The phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit delta gene (PIK3CD), associated with primary immunodeficiency disease (PID), encodes the p110δ catalytic subunit and is predominantly expressed in immune cells such as lymphocytes.
基金Beijing Natural Science Foundation of China(7152053)Beijing Municipal Science and Technology Project'The Capital characteristic Clinical Application Research'(Z141107002514130)Beijing Municipal Administration of Hospitals Clinical medicine Development of special funding support(code ZY201404).
文摘Importance: Immune thrombocytopenic purpura (ITP) is the most common bleeding disorder in children. Despite the highly spontaneously remission, still almost 20% of cases progress into chronic or refractory ITP, which seriously affects children's quality of life. Currently there is no method to predict the initial stage of childhood ITP. Objectives: To evaluate platelet-specific antibodies and compare differences in their expression in childhood ITP to predict clinical progression. Methods: This is a single-center prospective cohort study from April 2014 to October 2015. We enrolled children initially diagnosed as ITP. Anti-GPIIb/IIIa and GPIb/IX antibodies were assayed by enzyme-linked immunoadsorbent assay (ELISA) and patients were followed up for 1 year. We also analyzed the relationship between the expression of the platelet-specific antibodies GPIIb/IIIa and GPIb/IX and their respective clinical prognoses. results: Overall, 134 cases were enrolled including 77 boys and 57 girls with a median age of 19 months (range: 1 to 159). Positive rates of anti-platelet antibodies were 79.8%. After a 1-year observation period, 84.3%were diagnosed as newly diagnosed ITP and 13.4% were diagnosed as chronic ITP. Patients with anti-GPIIb/IIIa antibody had a higher risk for newly diagnosed ITP compared with patients who were anti-GPIb/IX antibody positive only (93% vs 25%, P = 0.005;87% vs 25%, P = 0.014, respectively). There were more anti-GPIb/IX antibody positive only cases, diagnosed as chronic ITP, compared with anti-GPIIb/IIIa antibody positive only cases and double GPIIb/IIIa and GPIb/IX antibody positive cases (75% vs 7%, P = 0.005;75% vs 13%, P = 0.014, respectively). Interpretation: Patients with anti-GPIIb/IIIa antibody (either single or double) were predicted to have a good prognosis, whereas anti-GPIb/IX antibody only predicted a poor prognosis. These results should be confirmed via a larger cohort multicenter study.
基金National Science and Technology Major Project(Grant/Award Number:2017ZX09304029001)Pediatric Special Project,Center for Collaborative Development of Pediatric Discipline,Beijing Hospital Administration(Grant/Award Number:XTZD20180205)。
文摘INTRODUCTION Primary immune thrombocytopenia(ITP)of childhood is an acquired,immune-mediated,bleeding disorder charac-terized by an isolated platelet counts decreased without an identifed cause during childhood.1 The main pathogenesis is loss of immune tolerance,which leads to immune-mediated platelet destruction and/or suppression of platelet production.
基金This work was supported by the National Science and Technology Major Projeet(no.2017ZX09304029001)Pediatric Special Project,Center for Collaborative Development of Pediatric Discipline,Beijing Hospital Administration(no.XTZD20180205)。
文摘Over the last few decades,a plethora of guidelines for primary immune thromboeytopenia(ITP)in children have been developed and published.However,the guidelines developed by one country or organization are not always appropriate to other countries or regions due to differences in local circumstances.
基金This work was supported in part by grants from research on the application of clinical characteristics of the Beijing Municipal Science and Technology Commission(code Z181100001718182)Capital Health Development Research Project(No.Capital Development 2018-2-2094)+1 种基金Beijing Natural Science Foundation of China(No.7162059)Beijing Municipal Administration of Hospitals Clinical medicine Development of special funding(code ZY201404).
文摘Importance:The use of factor VIII(FVIII)concentrates under pharmacokinetic(PK)guidance has become the main approach for treatment of hemophilia.However,limited PK research has been conducted in Chinese pediatric patients.Objective:To investigate the PK parameters of various FVIII concentrates in Chinese pediatric patients.Methods:Seventy-nine patients were enrolled(28 treated with Kogenate FS^(®),23 treated with Advate^(®),and 28 treated with GreenMono^(™)).All enrolled patients participated in single-dose PK analysis after at least a 3-day washout period.Blood samples were collected predose,as well as at 1 h,9 h,24 h,and 48 h after infusion;FVIII levels were measured using a one-stage clotting assay,von Willebrand Factor Antigen(VWF:Ag)levels and blood types were also determined.PK parameters were evaluated by WAPPS-Hemo.Results:Mean values of terminal elimination half-life time(t_(1/2))for the Kogenate FS^(®),Advate^(®),and GreenMono^(™)FVIII groups were 12.24 h,10.18 h,and 9.62 h;median clearance values were 4.16,6.23,and 5.11 mL kg^(-1)h^(-1);and median in vivo recovery values were 1.97,1.55,and 1.61 IU/dL per IU/kg.Longer t_(1/2),higher in vivo recovery,and lower clearance were observed in patients with higher VWF:Ag level who were treated with recombinant concentrates.Interpretation:Chinese pediatric patients with hemophilia had FVIII PK characteristics similar to those previously observed in non-Chinese children,including large variation among individuals.VWF:Ag level and FVIII brand were associated with differences in FVIII PK.Thus,PK-guided dosing should be used to optimize individualized therapy in Chinese children.
文摘INTRODUCTION
Congenital neutropenia (CN) is a rare primary immunodeficiency disease that includes severe congenital neutropenia (SCN) as a major subtype. SCN was first described in 1956 by Rolf Kostmann, and is characterized by an absolute neutrophil count (ANC) of <0.5×109/L. SCN patients can also develop acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS).1 In this study, we report two pediatric patients from one family with SCN associated with the neutrophil elastase gene (ELANE).