[Study on pharmacokinetics and tissue distribution characteristics of salidroside in mice].

The present study aims to establish a method for determination of salidroside in plasma and tissues of mice, and to study the pharmacokinetics and distribution characteristics of salidroside in mice. After intragastrically administered of salidroside at doses of 12.30, 36.90 and 73.80 mg·kg~(-1) to mice, plasma and tissue samples were collected, and the concentration of salidroside in each sample was measured by UPLC-MS/MS to study plasma drug parameters and tissue distribution of salidroside. Salidroside showed a good linear relationship in the plasma and tissues of mice in the concentration range of 43.40-5 556 ng·mL~(-1). The intraday and interday precision are less than 15%, and the accuracy is between 79.50% and 98.20%. The tissue distribution study found that salidroside had higher plasma concentration, and the plasma concentration reached the maximum at 0.5 h. After 6 h, no salidroside was detected in the plasma, indicating that salidroside has good solubility and absorption fast, clearance is also fast. In tissues, the concentration of liver and kidney tissues is higher, indicating that salidroside liver and kidney are the main metabolic and excretory organs. The established method is easy to operate and has good precision. It is suitable for salidroside in mice. Pharmacokinetics and tissue distribution studies provide a reference for the mechanism of action and drug development of salidroside.

MYO3B promotes cancer progression in endometrial cancer by mediating the calcium ion-RhoA/ROCK1 signaling pathway.

PURPOSE: This study aimed to investigate the effect of MYO3B on endometrial cancer (EC) proliferation and invasion. METHODS: The expression of MYO3B in EC tissues and cells was analyzed using TCGA database, immunohistochemical staining, real-time PCR, and western blot (WB). Cell proliferation was detected by CCK8, Annexin V-APC/PI flow cytometry was used to detect apoptosis, intracellular calcium ion (Ca2+) was detected by flow cytometry with Fluo-4 AM fluorescent probe, cell migration by scratch assay, and cell invasion by Transwell assay, and the expression of proteins related to Ca2+ homeostasis and RhoA/ROCK1 signaling pathway was detected by WB and immunofluorescence staining. RESULTS: The expression of MYO3B was an influential factor in EC recurrence, and the expression of MYO3B was significantly up-regulated in EC tissues and cells, but down-regulated in KLE cells, and MYO3B knockdown inhibited the proliferation, migration, and invasion ability of EC cells and promoted apoptosis, suggesting that MYO3B plays a tumor-promoting role in EC. Furthermore, MYO3B knockdown decreased Ca2+ concentration in EC cells and the RhoA/ROCK1 signaling pathway was inhibited, and the effect of MYO3B knockdown on RhoA/ROCK1 signaling was reversed by treatment with the Calmodulin agonist CALP-2, and the effects of MYO3B knockdown on cell proliferation, migration, and invasion were reversed after treatment with the RhoA agonist U-46,619. CONCLUSION: MYO3B promotes the proliferation and migration of endometrial cancer cells via Ca2+-RhoA/ROCK1 signaling pathway. High expression of MYO3B may be a biomarker for EC metastasis.

Guided selection methods through chain shuffling.

We provide procedures for the panning of fully humanized Fab antibodies using guided selection. Human heavy and light chain genes are amplified. A parental light chain is cloned into a phage display vector and combined with the heavy chain library. After several rounds of panning, positive clones are identified and the heavy chain sequences that are recovered are combined with light chains for further selection by phage display. Human Fab antibodies are obtained that bind the same epitope as the parental antibody.

Optimization of Phenylphthalein and Phenolic Acid Components Extracts from Angelicae Sinensis Radix-Chuanxiaong Rhizoma Decoction Pieces by Central Combination Design Response Surface Methodology / 中国中医药信息杂志

Objective To optimize the optimal extraction process for phthalein and phenolic acid components in Angelicae Sinensis Radix-Chuanxiaong Rhizoma decoction pieces.Methods On the basis of a single factor experiment,central combination design-response surface methodology was adopted,and the extraction time,ethanol concentration,and ethanol dosage were used as influencing factors,and the total normalized values of the content of Senkyunolide I,Senkyunolide A and ligustilide,and extract yield were used as evaluation indicators to optimize the extraction process of phthalein components in Angelicae Sinensis Radix-Chuanxiaong Rhizoma decoction pieces;the total normalized values of chlorogenic acid,caffeic acid,ferulic acid,and extract yield were used as evaluation indicators to optimize the extraction process of phenolic acids components in Angelicae Sinensis Radix-Chuanxiaong Rhizoma decoction pieces.Results The optimal extraction process was to add 7 times the amount of 90%ethanol to the phthalein components,extract for 130 minutes each time,and extract twice;phenolic acid components were extracted twice with 7.5 times the amount of 65%ethanol for 120 minutes each time.Conclusion The optimized extraction process for phthalein and phenolic acids in Angelicae Sinensis Radix-Chuanxiaong Rhizoma decoction pieces is stable and feasible,which can provide a basis for subsequent research.

Visual analysis of the impact of T cells on rheumatoid arthritis in the past decade based on multiple analysis methods / 中国现代医生

@#Objective Through a multi-software visual analysis of the literature on the influence of T cells on rheumatoid arthritis(RA)in recent ten years,the research hotspot and frontier development in this field were summarized.Methods The Chinese and English literature on the influence of T cells on RA from 2012 to 2022 years was retrieved from CNKI and Web of Science database as the research object.CiteSpace and VOSviewer software were used to analyze the number of publications,authors and keywords.Results 519 articles in Chinese and 861 in English were retrieved.The results showed that the number of articles in Chinese increased slowly from 2020 to 2022 years,while the overall trend in English was stable.Keyword analysis shows that it is predicted that future research in this field will focus on the pathogenesis of T cells in RA,the mechanism of bone destruction in RA,disease activity,oxidative stress.Conclusion The influence of T cells on RA has attracted much attention in the past,present and future,and has great research value.However,due to the differences in research priorities at home and abroad,the teams should interact positively and communicate with each other to reveal the internal mechanism of RA and provide theoretical basis for targeted therapy.

Impact of hypophosphatemia on weaning from mechanical ventilation / 中华危重病急救医学

Objective:To explore the influence of hypophosphatemia on weaning from mechanical ventilation.Methods:An observational study was conducted. The medical records of 30 mechanical ventilated patients with hypophosphatemia admitted to intensive care unit of Sun Yat-sen Memorial Hospital of Sun Yat-sen University from January 2018 to August 2020 were analyzed; another 60 mechanical ventilated patients with normophosphatemia around the same time were enrolled as controls by 1∶2 case-control matching based on gender, age, acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) score, sequential organ failure assessment (SOFA) score. And then the duration of invasive mechanical ventilation, times of spontaneous breathing trial (SBT), the diaphragmatic ultrasonography movement indexes, and outcome of weaning and prognosis during hospitalization were compared between the two groups. Receiver operator characteristic curve (ROC curve) was plotted to calculate the areas under ROC curve (AUC) and cut-off values of serum phosphorus for successful weaning and hospital survival. The correlations between the diaphragmatic ultrasonography movement indexes and serum phosphorus were analyzed by Pearson partial correlation analysis.Results:Compared with normophosphatemic group, the duration of invasive mechanical ventilation in hypophosphatemia group was significantly longer [days: 13.0 (7.0, 22.0) vs. 10.0 (5.5, 14.0), P < 0.05], and SBT attempts were more often [times: 3 (0, 5) vs. 1 (1, 2), P < 0.01], while the rate of successful weaning was lower (53.3% vs. 91.7%, P < 0.01), and the hospital mortality was higher (20.0% vs. 1.7%, P < 0.01). ROC curve analysis showed that serum phosphorus could predict successful weaning of mechanical ventilated patients, the AUC was 0.795, and the optimum cut-off value of serum phosphorus was 0.85 mmol/L with sensitivity of 73.2% and specificity of 84.2%. Serum phosphorus could predict hospital survival of mechanical ventilated patients, the AUC was 0.782, and the optimum cut-off value of serum phosphorus was 0.48 mmol/L with sensitivity of 81.9% and specificity of 85.7%. Compared with normophosphatemic group, diaphragm thickness at the end of inspiration (DTei), diaphragm thickness at the end of expiration (DTee), diaphragm thickening fraction (DTF), diaphragm excursion (DE) in hypophosphatemia group were all significantly decreased [DTei (cm): 0.19±0.07 vs. 0.27±0.08, DTee (cm): 0.14±0.05 vs. 0.19±0.06, DTF: (33.55±16.17)% vs. (45.04±18.66)%, DE (cm): 1.17±0.49 vs. 2.28±0.69, all P < 0.01]. Pearson partial correlation analysis showed that linear correlations were found between serum phosphorus and DTei, DTee, DTF, DE ( r values were 0.442, 0.351, 0.293, 0.628 respectively, all P < 0.01). Conclusions:Serum phosphorus may have correlation with the diaphragmatic ultrasonography movement indexes. Hypophosphatemia may impair the contractile properties of diaphragm, induce more SBT attempts and longer duration of invasive mechanical ventilation, and affect outcome of weaning and prognosis.

Research Overview on Content Determination Methods of Total Flavonoids in Effective Parts of Chinese Materia Medica / 中国中医药信息杂志

The flavonoids are the active ingredients of many Chinese materia medica, with widespread biological activities and a wide range of clinical application. There are many types of flavonoids, and its chemical structure is complex. Quantitative analysis of only one or several valid / indexed components may not necessarily reflect the amount of total flavonoids, with some limitations. The content determination of total flavonoids in effective parts of Chinese materia medica is an important aspect of quality control. The main methods for determining total flavonoid content are as follows: UV-visible spectropho-tometry, fluorescence spectrophotometry, high performance liquid chromatography, capillary electrophoresis, thin layer chromatography, as well as near-infrared spectroscopy and so on. In this article, the methods and characteristics in the determination of total flavonoids in Chinese materia medica were reviewed, so as to provide references for the quality control of Chinese materia medica.

Study on Improving the Quality Standard of Gubi Zhitong Liquor / 中国药房

OBJECTIVE:To improve the quality standard for Guibi zhitong liquor. METHODS:TLC was used for the qualita-tive identification of Radix angelicae,Notopterygium incisum,Radix aucklandiae and Magnolia officinalis in the preparation;HPLC was used for the contents determination of imperatorin and cinnamaldehyde:the column was Waters Symmetry Shield RP-C18 with mobile phase of methanol-water for imperatorin(60:40,V/V)and methanol-water for cinnamaldehyde(35:65,V/V)at a flow rate of 1.0 mL/min,detection wavelength was 254 nm for imperatorin and 290 nm for cinnamaldehyde,column temperature was 25℃,and the injection volume was 20μL. RESULTS:The TLC spots of R. angelicae,N. incisum,R. aucklandiae and M. of-ficinalis were clear and well separated,negative control without interference. The linear range was 3.0-30.0 μg/mL for imperatorin (r=0.9998)and 3.978-39.78 μg/mL for cinnamaldehyde(r=0.9999);RSDs of precision,stability and reproducibility tests were lower than 2.0%;recoveries were 96.94%-102.64%(RSD=2.37%,n=6)and 96.78%-99.53%(RSD=1.00%,n=6). CONCLU-SIONS:The improved standard more effectively control the quality of the Guibi zhitong liquor.

Application of diffusion kurtosis imaging in differential diagnosis of parotid gland disease and diagnosis of parotid adenolymphoma / 中国医学影像技术

Objective To investigate the value of diffusion kurtosis imaging (DKI) in differential diagnosis of parotid gland disease and diagnosis of parotid adenolymphoma (PAL).Methods DKI and DWI data of 57 patients with parotid gland disease were etrospectively analyzed.Totally 57 cases were divided into infectious lesions group (n=10),pleomorphic adenoma group (n=19),PAL group (n=14),other benign parotid tumor group (n=4) and malignant parotid tumor group (n=10).Contralateral normal parotid glands in 19 patients with unilateral parotid gland lesions were treated as control group.The quantitative parameters including kurtosis concerning parameters (K Krad,Kax),diffusivity concerning parameters (D Drad,Dax),fractional anisotropy (FA) and conventional apparent diffusion coefficient (ADC) values were retrospectively reviewed.The binary Logistic regression method was used to confirm parameters with significant difference in diagnosing PAL.And Logistic regression equation was constructed to diagnose PAL.ROC analysis was conducted to evaluate the diagnostic value of the confirmed parameters and the Logistic regression equation.Results Significant difference of the parameters including K Krad,Kax,D Drad,Dax,FA and ADC values were found among different groups (all P＜0.05).ROC analysis demonstrated a higher area under the curve (AUC) for FA+Kax [0.88±0.06 (0.79-0.94)] than Kax[0.80±0.07 (0.70-0.88)] and FA [0.63±0.10 (0.52-0.73)],respectively (both P＜0.05).The sensitivity,specificity,accuracy,positive predictive value and negative predictive value was 71.43％,95.78％,91.77％,76.92％ and 94.44％.Conclusion DKI showed high diagnostic capacity in differential diagnosis of parotid gland disease.The combination of FA and Kaxcan improve the diagnostic accuracy in diagnosis of PAL.

Detection of Amino Acids and Polypeptides by Electrospray Ionization-Ion Mobility Spectrometry / 分析化学

The electrospray ionization-ion mobility spectrometric (ESI-IMS) technique has the potential as an analytical separation tool in analyzing polypeptides and amino acids for fast screening unknown samples in anti-chemical and biological terror attacks. A method for detecting several polypeptides and amino acids was developed based on ESI-IMS using air as drift gas at room temperature. The ion mobility of four amino acids and two polypeptides dissolved in methanol was determined on the system at elution rate of 2 mL/ min. The spectra of these compounds had characteristics of finger-printing maps. The limit of detection of this instrument for Substance P could reach 855 ng / mL in 1 min. The results showed that a small, self-contained ESI-IMS instrument with reservoirs of air could be used to quickly detect and accurately identify polypeptides and amino acids.

Study on Determination Method of Total Flavonoids in Gansu Astragali Radix and ;Hedysarum Polybotrys / 中国中医药信息杂志

Objective To study the determination method of total flavonoids in Gansu Astragali Radix and Hedysarum Polybotrys. Methods Calycosin glycosides etc. was selected as reference substances, comparison on the difference of absorption curves was done by ultraviolet spectroscopy and colorimetric method (NaNO2-Al(NO3)3-NaOH, AlCl3, Mg(Ac)2, NaOH, phosphomolybdic acid, HCl-Mg power). Results With colorimetric method, the maximum absorption wavelength of referrence and the test was inconsistent. The absorption peak shape was also different. With UV method, Calycosin glycosides in band Ⅱ (260 nm) showed a shoulder absorption. Astragali Radix and Hedysarum Polybotrys also showed characteristic shoulder absorptions in band Ⅱ with absorption wavelength at 263 nm and 265 nm. So the sample absorption wavelength is basically the same as that of the control sample. Conclusion Colorimetries usually used for determination of total flavonoids are not suitable for the comparison determination of Gansu Astragali Radix and Hedysarum Polybotrys. It is suitable for determining the contents of total flavonoids in samples by UV spectrophotometry at the band Ⅱ, which is the characteristic absorption band of isoflavone compound.

Study on Content Determination of Coumarin in Fraxini Cortex Extract / 中国中医药信息杂志

Objective To establish a UV spectrophotometry method and an HPLC method respectively for the determination of the total content of coumarin and contents of four main constituents of coumarin in Fraxini Cortex extract.Methods UV spectrophotometry was used for the determination of the content of total coumarin in Fraxini Cortex extract. The reference substance was Aesculin, and the maximum ultraviolet absorption wavelength was 334 nm. The HPLC method was used to determine the contents of Aesculin, Fraxin, Aesculetin and Fraxetin in Fraxini Cortex extract, using gradient elution with acetonitrile-phosphate solution (0.01%) as mobile phase on Agilent ZORBAX SB-C18 chromatographic column (4.6 mm × 250 mm, 5μm) at room temperature.Results For the UV method, the linear range of the mass concentration of Aesculin was 5.76-23.04μg/mL (r=0.999 9), and the average recovery was 100.6% (RSD=1.8%). For the HPLC method, the linear ranges of the mass of Aesculin, Fraxin, Aesculetin and Fraxetin were 0.055 0-3.850 0μg (r=0.9997), 0.053 9-3.773 0μg (r=0.999 8), 0.060 0-0.660 0μg (r=0.999 9), and 0.056 2-0.618 2μg (r=0.999 9), respectively, and the average recoveries were 96.97% (RSD=1.26%), 100.80% (RSD=2.22%), 99.04% (RSD=2.47%), and 98.77% (RSD=1.94%), respectively.Conclusion Both of the two methods are simple, accurate and reliable, and can be used for the quality control of total coumarin and the main constituents of coumarin in Fraxini Cortex extract.

Comparative Study on Cortex Fraxini Total Coumarin of Different Extraction Processes / 中国中医药信息杂志

Objective To study the effects of different extraction processes on extraction rate of cortex fraxini total coumarin and active constitute percentage of major coumarin;To establish a proper extraction process.Methods Orthogonal design method was applied to set comprehensive index cortex fraxini total coumarin extraction rate as inspecting index. Water and alcohol were used as solvent respectively to optimize the extraction process of cortex fraxini.Results Optimal water extraction process:cortex fraxini decoction pieces mixed with nine times of water, decocted for three times, 90 mins each time. The pasty fluid generating rate of cortex fraxini was 28.87%, total coumarin percentage was 19.26%, extraction rate was 5.56%, total percentage of Aesculin, Aesculetin, Fraxin, Fraxetin was 13.47%, when water was used as solvent. Optimal alcohol extraction process:cortex fraxini decoction pieces mixed with eight times of 75% ethyl alcohol, refluxed twice, two hours each time. The pasty fluid generating rate of cortex fraxini was 30.47%, total coumarin percentage was 21.72%, extraction rate was 6.62%, total percentage of Aesculin, Aesculetin, Fraxin, Fraxetin was 15.29%, when alcohol was used as solvent. It was found that using alcohol as solvent had a 5.54% higher pasty fluid generating rate, a 12.77% higher total coumarion percentage, a 19.06% higher total coumarin extraction rate, and a 13.51% higher percentage of total four coumarin constitutes than using water, with statistical significance. Conclusion Extraction process by using alcohol as solvent is better than using water. So the optimal and stable extraction process of cortex fraxini total coumarin is using 75% alcohol as solvent.

MRI and Pathological Features of Ovarian Endometrioid Adenocarcinoma / 中国医学影像学杂志

PurposeTo study the MRI and pathological features of ovarian endometrioid adenocarcinoma (OEC) in order to evaluate the value of MRI in diagnosing OEC. Materials and Methods The MRI imaging features of 8 patients confirmed by surgery and pathology were analyzed retrospectively and were compared with the results of surgery and pathology. The MRI outcome and the related histological findings were further analyzed.Results Six out of the eight patients had unilateral tumor, 3 tumors in the left and the other 3 in the right; 2 patients had masses in the both ovaries. The total number of masses was ten.The diameters of the tumors ranged from 3.5 to 16.5 cm, with the average size of (10.5±4.1) cm. The border of 2 tumors was partially fuzzy and that of the other 6 was clear. The MRI scans showed that 8 tumors were cystic-solid and the other 2 were solid with heterogeneous signals. The solid components mainly presented slightly short T1 signals and long T2 signals; the cystic ones revealed long T1 and T2 signals. The enhanced scanning showed that the solid components of 8 tumors were patchy and obviously enhanced and the other 2 had mild or moderate enhancement. The cystic components were not hyper-intense. The enhanced MRI scans of two cases of primary endometrial carcinoma with metastases to the ovaries showed thickened endometrium and mild hyper-intense.Conclusion MRI can reveal the pathological features of OEC and clearly presents the forms, components and the relationship with its surroundings of tumors. Therefore, MRI is of great importance to the clinical diagnosis of OEC.

Analysis of respiratory complications in 922 severely burned patients / 中华烧伤杂志

<p><b>OBJECTIVE</b>To discuss the distribution of the respiratory complications in severely burned patients and the prevention and treatment experience against them.</p><p><b>METHODS</b>Medical records of 922 adult patients with severe or extremely severe burn hospitalized in our burn ICU from January 2005 to December 2012 were screened and retrospectively analyzed, including patients transferred from other hospitals, patients with total burn area above 50% TBSA, the distribution and treatment of respiratory complications, and the mortality. Data were processed with chi-square test.</p><p><b>RESULTS</b>The constituent ratio of patients transferred to our hospital was 71.1% in 2007 and 40.2% in 2010, while it remained about 50.0% in the other years. The ratios of patients with total burn area larger than 50% TBSA and that of patients with respiratory complications (χ(2) = 2.637, P > 0.05) showed no significant changes each year. Among these 922 burn patients, 523 patients suffered respiratory complications, among which laryngeal edema (50.9%, 266 cases), pulmonary infection (21.6%, 113 cases), and ARDS (11.9%, 62 cases) were the main components, with no significant change each year (with χ(2) values respectively 6.132, 6.319, 0.016, P values above 0.05). Among the patients with respiratory complications, except for 36 were not treated actively, 487 were treated by ventilator among which 228 had undergone tracheostomy, and the constituent ratios in the 8 years were close. Fifteen patients died, with 2 died of laryngeal edema, 3 of ARDS, and 10 of sepsis or MODS as a result of sepsis.</p><p><b>CONCLUSIONS</b>Patients with severe burns were at high risk of respiratory complications, among which laryngeal edema was common, followed by pulmonary infection and ARDS. Prophylactic tracheostomy, mechanical ventilation, wound therapy, and anti-infection were all effective measures of prevention and treatment against these complications.</p>

Alanine solution as enzyme reaction buffer used in A to O blood group conversion / 中国实验血液学杂志

The aim of this study was to investigate the effect of alanine solution as α-N-acetylgalactosaminidase enzyme reaction buffer on the enzymatic activity of A antigen. The binding ability of α-N-acetylgalactosaminidase with RBC in different reaction buffer such as alanine solution, glycine solution, normal saline (0.9% NaCl), PBS, PCS was detected by Western blot. The results showed that the efficiency of A to O conversion in alanine solution was similar to that in glycine solution, and Western blot confirmed that most of enzymes blinded with RBC in glycine or alanine solution, but few enzymes blinded with RBC in PBS, PCS or normal saline. The evidences indicated that binding of enzyme with RBC was a key element for A to O blood group conversion, while the binding ability of α-N-acetylgalactosaminidase with RBC in alanine or glycine solution was similar. It is concluded that alanine solution can be used as enzyme reaction buffer in A to O blood group conversion. In this buffer, the α-N-acetylgalactosaminidase is closely blinded with RBC and α-N-acetylgalactosaminidase plays efficient enzymatic activity of A antigen.

[Multicentral randomized controlled trials of acupuncture at Zhongwan (CV 12) for treatment of peptic ulcer].

OBJECTIVE: To evaluate the efficacy and safety of acupuncture at Zhongwan (CV 12) for treatment of peptic ulcer. METHODS: Two hundred and seventy-six cases enrolled were randomly divided into an acupuncture group and a control group, 138 cases in the acupuncture group were treated with deep needling at Zhongwan (CV 12) with a long needle, and 138 cases in the control group were treated with climetidine. The therapeutic effects were evaluated by clinical symptoms and gastroscopy. They were investigated for 6 weeks. RESULTS: The acupuncture group was better than the control group in rapid alleviation of stomachache and improvement of appetite (P < 0.05). The total effective rate was 90.6% in the acupuncture group and 88.4% in the control group with no significant difference (P > 0.05). The symptoms improved significantly in the two groups (P < 0.01), but with no significant difference between the two groups (P > 0.05). There was no significant difference between the two groups in the therapeutic effect of gastroscopy (P > 0.05). CONCLUSION: Acupuncture at Zhongwan (CV 12) has a reliable therapeutic effect on peptic ulcer.

Removal of αGal xenotransplantation antigen by a novel α-galactosidase / 中国实验血液学杂志

αGal, a xenotransplantations antigen (XTA), can lead to hyper acute reaction (HAR) in xenotransplantation. α-Galactosidase from B. fragilis is a novel galactosidase belong to CAZy GH110 which can clear the terminal αGal from branched and linear oligosaccharides. This study was purposed to investigate the removal effect of a novel α-galactosidase on α-Gal XTA on surface of red blood cells. The αGal XTA from the red blood cells of cattle, pig, dog and rabbit was digested by using recombinant α-galactosidase; the α-Gal antigens on surface of cells was detected by flow cytometry. The results showed that the XTA was disappeared completely or mainly. It is concluded that the novel α-galactosidase is a potential enzyme to remove the XTA on the surface of xenotransplants and can be used to overcome the HAR in xenotransplantation.

A reconstructed B. Fragilis-derived recombinant α-galactosidase developed for human blood type B→O conversion / 中国实验血液学杂志

This study was aimed to prepare a reconstructed B. Fragilis-derived recombinant α-galactosidase developed for human B to O blood group conversion. Based on the construction of recombinant E. Coli (DE3) which can express α-galactosidase, the inducing time and inducer concentration were optimized for high expression of α-galactosidase. Then, the expression products in supernatant were purified by cation and anion exchange column chromatography. The purified α-galactosidase was used to treat B group red blood cells in phosphate buffer (pH 6.8) for 2 hours to prepare O group red blood cells. The results showed that the optimal inducing conditions for α-galactosidase expression were IPTG 0.1 mmol/L, 37°C and 2 hours. The specific enzyme activity of purified protein increased from 0.42 U/mg to 2.1 U/mg as compared with pre-purification. And, the conditions of B to O blood group conversion were 26°C, pH 6.8 (neutral pH condition) and 2 hours. Moreover, 225 µg of the enzyme could converse 1 ml B red blood cells to O completely. It is concluded that the technology of expression and purification of recombinant α-galactosidase has been established, and the purified protein can converse B red blood cells to O completely, which means that an effective enzyme conversing B red blood cells to O has been obtained.

Signal pathways of eryptosis-review / 中国实验血液学杂志

Erythrocytes are devoid of nuclei and mitochondria which are the crucial elements of apoptosis, so their programmed suicidal death is called eryptosis. Eryptosis is characterized by cell shrinkage, membrane blebbing, activation of proteases, and phosphatidylserine exposure. Prostaglandin E(2) (PGE(2)) activates nonselective cation channels that increase cytosolic Ca(2+) activity and platelet-activating factor (PAF) activates a sphingomyelinase which lead to formation of ceramide. Either can lead to membrane scrambling with subsequent phosphatidylserine exposure. Exposed phosphatidylserine is recognized by macrophages that engulf and degrade the injured cells. As such, eryptosis can clear the injured red blood cells and avoid the release of hemoglobin. The signaling of eryptosis includes PGE(2), cation channels, PAF, ceramide, protein kinase C, and in some instances, caspases. In this review, the PGE(2), PAF and protein kinase pathways, erythrocyte surface receptor-mediated effects, oxidative stress and caspase effects, the inhibitory factors of eryptosis and the clinical eryptosis-related diseases are discussed.