BACKGROUND: We evaluated the performance of the TOSOH glycohemoglobin analyzer HLC-723GHb V A1c 2.2TM (TOSOH Corp. Kyoto, Japan), a recently introduced automated hemoglobin A1c (HbA1c) analyzer using high performance liquid chromatography (HPLC) method without sample pretreatment. METHODS: The performance characteristics evaluated were precision, linearity, comparison with VARIANTTM (Bio-Rad, Germany) and throughput following NCCLS evaluation protocols (EP5-T2, EP6-P, and EP9-T). RESULTS: The within-run and between-day CV's were 0.910 and 1.328 for low level (6.2%), 1.214 and 1.460 for middle level (8.5%), and 0.789 and 1.449 for high level (10.7%), respectively. We found the perfect linearity of HbA1c (%) from 6.5 to 10.2 (r2=0.9995). Comparison studies between A1c 2.2 and VARIANTTM yielded the following correlation equations; A1c 2.2TM = 0.9915 (VARIANTTM) + 0.1198 %HbA1c (r=0.9936, P < 0.0001). Throughput was 28.0 tests per hour for A1c 2.2TM compared with 15.2 tests for VARIANTTM, which were determined including red blood cell lysis time before sample loading for VARIANTTM. A1c 2.2TM did not need sample pretreatment. CONCLUSIONS: With the above results, A1c 2.2TM shows acceptable performance and is suitable for routine use in the clinical laboratory.
Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Erythrocytes

Eight isoflavonoid compounds were isolated from the EtOAc fraction of Maackia amurensis which had shown the highest anti-Helicobacter pylori activity among the fractions, using medium pressure liquid chromatography and recrystallization. Based on the spectroscopic data including 1H-NMR, 13C-NMR, HMBC and MS data, the chemical structures of the isolates were determined to be (-)-medicarpin (1), afromosin (2), formononetin (3), tectorigenin (4), prunetin (5), wistin (6), tectoridin (7) and ononin (8). Anti-H. pylori activity of each compound was evaluated with broth dilution assay. As a result, (-)-medicarpin (1), tectorigenin (4) and wistin (6) showed anti-H. pylori activity. (-)-Medicarpin (1) exhibited the most potent growth inhibitory activity against H. pylori with the minimal inhibitory concentration (MIC)90 of 25 microM, and tectorigenin (4) with MIC90 of 100 microM ranked the second. This is the first study to show the anti-H. pylori activity of M. amurensis, and it is suggested that the stem bark of M. amurensis or the EtOAc fraction or the isolated compounds can be a new natural source for the treatment of H. pylori infection.
Chromatography, Liquid ; Maackia*

BACKGROUND: We evaluated the performance and analysis time of HLC-723 G7 (Tosoh corp. Tokyo, Japan) hemoglobin (Hb) A1c autoanalyzer. It utilizes cation exchange high performance liquid chromatography (HPLC) method and has a reduced analysis time compared with that of an earlier model HLC-723GHb V A1c 2.2(TM) (HLC-723GHb V, Tosoh corp. Tokyo, Japan). METHODS: We evaluated linearity, precision and comparison with HLC-723GHb V following NCCLS guidelines and counted the number of tests per hour to estimate analysis time. RESULTS: Linearity through the range from 5.8% to 13.9% was good (r2=0.9930, relative nonlinearity <2.5%). The within-run coefficients of variation (CVs) for groups of low, middle, and high level were 1.09%, 0.76%, and 0.68% and total CVs for each group were 1.60%, 0.91%, and 1.00%, respectively. Correlation equation between HLC-723 G7 and HLC-723GHb V was HLC-723 G7=1.0308 (HLC-723GHb V)-0.2896 %Hb A1c (r=0.9992, P<0.0001). Analysis time of HLC-723 G7 was 1.2 minutes per test compared with 2.1 minutes of HLC-723GHb V. CONCLUSIONS: HLC-723 G7 showed the acceptable performance and shortening analysis time therefore, it was suitable for reducing turn around time of Hb A1c assay.
Chromatography, Liquid ; Hemoglobin A, Glycosylated

No abstract available.
Chromatography, Liquid* ; Humans*

High-performance countercurrent chromatography (HPCCC) coupled with reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed to isolate dihydrophaseic acid 3′-O-β-D-glucopyranoside (DHPAG) from the extract of Nelumbo nucifera seeds. Enriched DHPAG sample (2.3 g) was separated by HPCCC using ethyl acetate/n-butanol/water system (6:4:10, v/v/v, normal-phase mode, flow rate: 4.0 mL/min) to give 23.1 mg of DHPAG with purity of 88.7%. Further preparative RP-HPLC experiment gave pure DHPAG (16.3 mg, purity > 98%). The current study demonstrates that utilization of CCC method maximizes the isolation efficiency compared with that of solid-based conventional column chromatography.
Chromatography ; Chromatography, Liquid ; Countercurrent Distribution ; Methods ; Nelumbo

BACKGROUND: Hemoglobin A1c (HbA1c) is widely used for the monitoring of glycemic control. A wide variety of different analytical methods is currently used by clinical laboratories. We performed this study to evaluate the newest ion-exchange high-performance liquid chromatography system, the HLC-723 G7 (Tosoh Corporation, Tokyo, Japan) automated glycohemoglobin analyzer. METHODS: HLC-723 G7 was evaluated for linearity, precision, comparison of method, and speed. HLC-723 G7 was compared with three analyzers including HLC-723 GHb V A1c 2.2, Variant II, and Cobas Integra 800. RESULTS: HLC-723 G7 showed within-run and total imprecision (CVs) of less than 2.5% and excellent linearity to at least 13.0%. HbA1c values obtained from HLC-723 G7 were strongly correlated with those from HLC-723 GHb V A1c 2.2. Comparison with two other methods showed a good correlation but revealed calibration differences throughout the analytical range. HLC-723 G7 required no sample preparation and showed a fast analytical time of 1.6 min. CONCLUSIONS: HLC-723 G7 provides high throughput and excellent precision. However, HbA1c values can differ considerably with different methods or instruments. Therefore, we should be aware of the potential problem in switching the HbA1c testing method
Calibration ; Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Diabetes Mellitus

BACKGROUND: Cation exchange-high performance liquid chromatography (CE-HPLC) is most commonly used to evaluate hemoglobin (Hb) variants, which elute in the Hb A2 window. This study aimed to assess prevalence of an uncommon Hb variant, Hb D-Iran, and compare its red cell parameters and peak characteristics with those of Hb E that commonly elutes in the Hb A2 window. METHODS: Generally, we assess abnormal Hb using CE-HPLC as the primary technique along with alkaline and acid electrophoresis. All cases with Hb A2 window >9%, as assessed by CE-HPLCs during 2009–2013, were selected. RESULTS: Twenty-nine cases with Hb D-Iran variant were identified—25 heterozygous, 2 homozygous, 1 compound heterozygous Hb D-Iran/β-thalassemia, and 1 Hb D-Iran/Hb D-Punjab. Overall prevalence of Hb D-Iran was 0.23%. Compared to patients with Hb E, those with Hb D-Iran had significantly higher Hb (12.1 vs. 11.3 g/dL, P=0.03), MCV (82.4 vs. 76.4 fL, P=0.0044), MCH (27.9 vs. 25.45 pg, P =0.0006), and MCHC (33.9 vs. 33.3 g/dL, P=0.0005). Amount of abnormal Hb (40.7 vs. 26.4%, P=0.0001) was significantly higher while retention time (3.56 vs. 3.70 min, P=0.0001) was significantly lower in Hb D-Iran than in Hb E. CONCLUSION: Hb D-Iran peak can be easily missed if area and retention time of the Hb A2 window are not carefully analyzed. To distinguish between variants, careful analysis of peak area and retention time is sufficient in most cases and may be further confirmed by the second technique—alkaline electrophoresis.
Chromatography, Liquid ; Electrophoresis ; Humans ; Prevalence

No abstract available.
Chromatography, Liquid* ; Ciprofloxacin* ; Therapeutic Equivalency*

To evaluate,the differences of benzidine exposure patterns of the workers in two benzidine-based dye manufacturing factories, the concentration of benzidine: in. air, blood, and urine were measured. The air levels of benzidine dihydrochloride and benzidine-based dye were measured by high performance liquid chromatography with ultraviolet detector. Blood samples were collected at 3 hours after exposure and urine samples were collected at the end of shift. Blood and urine samples were analyzed by high performance liquid chromatography with electrochemical detector. The level of benzidine in reaction process (input, diazotization, and coupling); was 0.381+/-7950 g/m3. The blood benzidine was deteced in 25 workers among 38 in reaction process and their mean levels were 0.0153?0376 ng/mg Hb. The urinary benzidine was detected for 11 workers among 38 workers in the reaction process. The level of benzidine-based dye in drying and packing process was 52.1748+/-4.4111g/m3. The blood benzidine was deteced in 6 workers among 38 in drying and packing process and their mean levels was 0.0062+/-0274 ng/mg Hb. The urinary benzidine was detected for 1 worker among 38 workers exposed to benzidine-based dye. The blood and urinary benzidine were detected in workers exposed to benzidine-based dye. Such results suggested that some part of benzidine-based dye was metaboized to benzidine. Therefore, some regulations for manufacturing and use of the benzidine-based dye are needed to prevent its hazards in industries.
Chromatography, Liquid ; Social Control, Formal

BACKGROUND: Hemoglobin A1c (HbA1c) is a useful marker for the diagnosis and monitoring of diabetes, which has resulted in an increasing dependency on HbA1c levels for diagnosing diabetes in small- and medium-sized hospitals. We evaluated a high performance liquid chromatography (HPLC) based HbA1c autoanalyzer Bio-Rad D-10 (Bio-Rad Laboratories, USA) by comparing the analysis results with that by Tosoh HLC-723 G7 (Tosoh Corporation, Japan). METHODS: The Bio-Rad D-10 autoanalyzer was evaluated for its precision, linearity, and carryover. The analysis time and correlation were evaluated and compared with those by Tosoh HLC-723 G7 autoanalyzer. RESULTS: Bio-Rad D-10 showed within-run, between-day, and total precision of less than 1.3% coefficient of variation (CV) and excellent linearity between HbA1c in the range of 3.2%-21% (coefficient of determination, R 2 = 0.998). The sampleto-sample carryover was 0.57%. The results obtained by using Bio-Rad D-10 showed good correlation (r = 0.997; P < 0.001) with those by Tosoh HLC-723 G7; however, the analysis time using Bio-Rad D-10 was about 2.3 times per 10 samples and 2.5 times per 20 samples than those using Tosoh HLC-723 G7. CONCLUSIONS: Bio-Rad D-10 showed good performance in assaying HbA1c. Bio-Rad D-10 autoanalyzer would be suitable for use in laboratories with small to medium amount of samples to be analyzed, but its initial analyzing time was longer than that by Tosoh HLC-723 G7.
Chromatography, Liquid ; Dependency (Psychology) ; Hemoglobins