A new strategy for quantitative analysis of a major clinical biochemical indicator called glycatedhemoglobin(Hb·A1c)was proposed.The technique was based on the simultaneous near-infrared(NIR)spectral determinatio...A new strategy for quantitative analysis of a major clinical biochemical indicator called glycatedhemoglobin(Hb·A1c)was proposed.The technique was based on the simultaneous near-infrared(NIR)spectral determination of hemoglobin(Hb)and absolute HbAlc content(Hb·HbA1c)inhuman hemolysate samples.Wavelength selections were accomplished using the improvedmoving window partial least square(MWPLS)method for stability.Each model was establishedusing an approach based on randomness,similarity,and stability to obtain objective,stable,andpractical models.The optimal wavebands obtained using MWPLS were 958 to 1036 nm for Hband 1492 to 1858 nm for Hb·HbA1c,which were within the NIR overtone region.The validationroot mean square error and validation correlation coeficients of prediction(V-SEP,V-Rp)were 3.4g L^(-1) and 0.967 for Hb,respectively,whereas the corresponding values for Hb.HbAic were 0.63 g L^(-1) and 0.913.The corresponding V-SEP and V-Rp were 0.40% and 0.829 for the relativepercentage of HbA1c.The experimental results confirm the feasibility for the quantification of HbAlc based on simultaneous NIR spectroscopic analyses of Hb and Hb·HbA1c.展开更多
Layer-by-layer {PDDA/Hb}(n) films were assembled by means of alternate adsorption of positively charged poly(diallyldimethyl ammonium) (PDDA) and negatively charged hemoglobin (Hb) at pH 9.2 from their aqueous solutio...Layer-by-layer {PDDA/Hb}(n) films were assembled by means of alternate adsorption of positively charged poly(diallyldimethyl ammonium) (PDDA) and negatively charged hemoglobin (Hb) at pH 9.2 from their aqueous solutions on pyrolytic graphite (PG) electrodes. Film growth during adsorption cycles was demonstrated by cyclic voltammetry and UV-Vis spectroscopy. Direct electrochemistry of Hb in {PDDA/Hb}(n) films on PG was studied.展开更多
Hemoglobin K-Woolwich (Hb KW) is a rare hemoglobin variant with very few cases reported. It is most prevalent in West African countries, particularly Nigeria, Ghana, and the Ivory Coast. Some reports suggest Hb KW may...Hemoglobin K-Woolwich (Hb KW) is a rare hemoglobin variant with very few cases reported. It is most prevalent in West African countries, particularly Nigeria, Ghana, and the Ivory Coast. Some reports suggest Hb KW may be a clinically benign trait, whereas others indicate it may behave similarly to a β+ thalassemia. The combination of hemoglobin S and hemoglobin KW (Hb S/KW) is a rare double heterozygous disorder with little known clinical characteristics. We report the hematologic and clinical data on three patients with Hb S/KW to help describe the characteristics of this patient population. The first two cases represent first cousins, ages 3 and 2 years. They are clinically asymptomatic. They have normal hemoglobin and mean corpuscle volume (MCV) levels without reticulocytosis. The third case is of a 14-year-old male who is non-anemic with no microcytosis. He has been clinically well except for abdominal pain upon dehydration. On hemoglobin electrophoresis, these patients have Hb S levels slightly higher than typically observed with sickle cell trait and a delay of hemoglobin F to adult levels. There exists a need for more reports to better delineate the clinical course and management of these patients.展开更多
Cation-exchange high-performance liquid chromatography(CE-HPLC) is a widely used laboratory test to detect variant hemoglobins as well as quantify hemoglobins F and A2 for the diagnosis of thalassemia syndromes. It...Cation-exchange high-performance liquid chromatography(CE-HPLC) is a widely used laboratory test to detect variant hemoglobins as well as quantify hemoglobins F and A2 for the diagnosis of thalassemia syndromes. It's versatility, speed, reproducibility and convenience have made CE-HPLC the method of choice to initially screen for hemoglobin disorders. Despite its popularity, several methodological aspects of the technology remain obscure to pathologists and this may have consequences in specific situations. This paper discusses the basic principles of the technique, the initial quality control steps and the interpretation of various controls and variables that are available on the instrument output. Subsequent sections are devoted to methodological considerations that arise during reporting of cases. For instance, common problems of misidentified peaks, totals crossing 100%, causes of total area being above or below acceptable limits and the importance of pre-integration region peaks are dealt with. Ultimately, CE-HPLC remains an investigation, the reporting of which combines in-depth knowledge of the biological basics with more than a working knowledge of the technological aspects of the technique.展开更多
基金supported by National Natural Science Foundation of China(No.61078040)the Science and Technology,Project of Guangdong Province(No.2012B031800917).
文摘A new strategy for quantitative analysis of a major clinical biochemical indicator called glycatedhemoglobin(Hb·A1c)was proposed.The technique was based on the simultaneous near-infrared(NIR)spectral determination of hemoglobin(Hb)and absolute HbAlc content(Hb·HbA1c)inhuman hemolysate samples.Wavelength selections were accomplished using the improvedmoving window partial least square(MWPLS)method for stability.Each model was establishedusing an approach based on randomness,similarity,and stability to obtain objective,stable,andpractical models.The optimal wavebands obtained using MWPLS were 958 to 1036 nm for Hband 1492 to 1858 nm for Hb·HbA1c,which were within the NIR overtone region.The validationroot mean square error and validation correlation coeficients of prediction(V-SEP,V-Rp)were 3.4g L^(-1) and 0.967 for Hb,respectively,whereas the corresponding values for Hb.HbAic were 0.63 g L^(-1) and 0.913.The corresponding V-SEP and V-Rp were 0.40% and 0.829 for the relativepercentage of HbA1c.The experimental results confirm the feasibility for the quantification of HbAlc based on simultaneous NIR spectroscopic analyses of Hb and Hb·HbA1c.
基金This work was supported by the National Natural Science Foundation of China.
文摘Layer-by-layer {PDDA/Hb}(n) films were assembled by means of alternate adsorption of positively charged poly(diallyldimethyl ammonium) (PDDA) and negatively charged hemoglobin (Hb) at pH 9.2 from their aqueous solutions on pyrolytic graphite (PG) electrodes. Film growth during adsorption cycles was demonstrated by cyclic voltammetry and UV-Vis spectroscopy. Direct electrochemistry of Hb in {PDDA/Hb}(n) films on PG was studied.
文摘Hemoglobin K-Woolwich (Hb KW) is a rare hemoglobin variant with very few cases reported. It is most prevalent in West African countries, particularly Nigeria, Ghana, and the Ivory Coast. Some reports suggest Hb KW may be a clinically benign trait, whereas others indicate it may behave similarly to a β+ thalassemia. The combination of hemoglobin S and hemoglobin KW (Hb S/KW) is a rare double heterozygous disorder with little known clinical characteristics. We report the hematologic and clinical data on three patients with Hb S/KW to help describe the characteristics of this patient population. The first two cases represent first cousins, ages 3 and 2 years. They are clinically asymptomatic. They have normal hemoglobin and mean corpuscle volume (MCV) levels without reticulocytosis. The third case is of a 14-year-old male who is non-anemic with no microcytosis. He has been clinically well except for abdominal pain upon dehydration. On hemoglobin electrophoresis, these patients have Hb S levels slightly higher than typically observed with sickle cell trait and a delay of hemoglobin F to adult levels. There exists a need for more reports to better delineate the clinical course and management of these patients.
文摘Cation-exchange high-performance liquid chromatography(CE-HPLC) is a widely used laboratory test to detect variant hemoglobins as well as quantify hemoglobins F and A2 for the diagnosis of thalassemia syndromes. It's versatility, speed, reproducibility and convenience have made CE-HPLC the method of choice to initially screen for hemoglobin disorders. Despite its popularity, several methodological aspects of the technology remain obscure to pathologists and this may have consequences in specific situations. This paper discusses the basic principles of the technique, the initial quality control steps and the interpretation of various controls and variables that are available on the instrument output. Subsequent sections are devoted to methodological considerations that arise during reporting of cases. For instance, common problems of misidentified peaks, totals crossing 100%, causes of total area being above or below acceptable limits and the importance of pre-integration region peaks are dealt with. Ultimately, CE-HPLC remains an investigation, the reporting of which combines in-depth knowledge of the biological basics with more than a working knowledge of the technological aspects of the technique.
