ABSTRACT
Diamond-Blackfan anemia(DBA)is a rare hereditary anemia.About 90% of them have symptoms in infancy, and about 50% are complicated with congenital malformations.Genetic abnormalities were found in 70% to 80% of DBA cases, mainly autosomal dominant inheritance, and a few were recessive or X-linked inheritance.The main gene mutations of DBA are ribosomal protein gene mutations and deletions.More than 20 mutation genes related to DBA have been found in the ribosomal protein(RP)gene encoding ribosome, of which RPS19 gene mutation is the most common.In addition, there are TSR2 genes related to ribosome function and non-RP genes related to DBA like phenotype, such as GATA1, EPO and ADA2 genes.These genes play a key role in the differentiation and proliferation of erythroid cells.Molecular diagnosis is an important criterion to diagnose and distinguish classical DBA from non-classical DBA.This review summarizes the latest research progress in the genetics, gene mutation and molecular diagnosis of DBA.
ABSTRACT
A new analytical method has been developed for the simultaneous determination of CrⅢand CrⅥusing on-line sample pretreatment valve-switching ion chromatography. The organic matrix in leather was removed by using a reverse-phase column as the pretreatment column. Before injection, EDTA was added into sample solution to react with the CrⅢto form anion which could absorb visible light strongly. After injection, the ions separated by the pretreatment column were received in a collection loop. Then the ions were delivered into an analytical column and separated. CrⅥ then was derived with the derivatization reagent 1, 5-diphenylcarbazide ( DPC) , and detected together with CrⅢ-EDTA complex by a UV-Vis detector. Under the optimum conditions, the linear range of the method for CrⅢ and CrⅥ was 0. 3-10 mg/L (r=0. 9991) and 0. 05-2 mg/L ( r = 0. 9992 ), whereas detection limits ( S/N = 3 ) were 80. 78 μg/L and 6. 67 μg/L, respectively. The recoveries were in the range of 88. 7%-108. 5% with the relative standard deviations for retention time and peak area less than 3%. The method could be applied to determine CrⅢ and CrⅥ in leather and cloth effectively and quickly.
ABSTRACT
A new method has been established for simultaneous determination of anions and cations in fertilizer sample by multimodal liquid chromatography with direct conductivity detection. An Acclaim Trinity P1 column based on nanopolymer silica hybrid technology with multimodal separation functional groups reversed-phase/anion-exchange/cation-exchange was used for the analysis. The chromatographic conditions were optimized and the effect ion of eluent on retention was discussed. Eight ions ( Li+, NH+4 , K+, HCOO-, NO-2 , Cl-, NO-3 and Br-) were separated and determined simultaneously by using 25 mmol/L CH3 COONa solution containing 50% acetonitrile at pH=5. 0 as mobile phase. The flow rate was 0. 50 mL/min and the temperature was 30 ℃. Under the optimum conditions, the linear ranges of the method were in the range of 0 . 5-200 mg/L for all the ions with correlation coefficient of 0 . 9997-0 . 9999 . Whereas the detection limits (S/N=3) were in the range of 0. 16-1. 72 mg/L and the relative standard deviations (RSD, n=9) were in the range of 1 . 3-2 . 5%. The method was applied to the determination of anions and cations in the fertilizer samples with satisfied results and the recoveries were in the range of 95 . 8%-103 . 8%.
ABSTRACT
The correlations between various formation conditions and the membrane pore characterizations of the anodic alumina membrane were investigated for seeking the optimal conditions for the formation of anodic alumina membrane. High purity aluminum foils were used as the starting materials. The anodizations were conducted under three types of electrolytes, 3% sulfuric acid, 5% sulfuric acid and 2.7% oxalic acid, respectively, with different voltages at 0 degrees C for 48 hours. The characterizations of the pore size, the effective porosity and the pore porosity were observed and determined by scanning electron microscopy. The hydraulic conductance of the membranes was measured to confirm that the pores were open and to evaluate the permselectivity of the membranes. The experimental results showed that the ordered pore arrays were obtained for oxidation under our experimental conditions. While the forming voltage was increasing, the pore size and pore porosity increased significantly (P < 0.05), and the effective porosity decreased significantly (P < 0.05). The pore size formed with 3% sulfuric acid or 5% sulfuric acid was much smaller than that with 2.7% oxalic acid as an electrolyte. The hydraulic conductance of anodic alumina membrane that formed under our experimental condition was high than those of the membranes currently available in clinical procedures. The results suggested that the optimal conditions for the formation of anodic alumina membrane to be used in hemodialysis should be 3% or 5% sulfuric acid with 12.5 V to 17.5 V at 0 degrees C for 48 hours.