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Electrocatalytic nitrogen reduction reaction (NRR) is a green and highly efficient way to replace the industrial Haber-Bosch process. Herein, clusters consisting of three transition metal atoms loaded on C2N as NRR electrocatalysts are investigated using density functional theory (DFT). Meanwhile, Ca was introduced as a promoter and the role of Ca in NRR was investigated. It was found that Ca anchored to the catalyst can act as an electron donor and effectively promote the activation of N2 on M3. In both M3@C2N and M3Ca@C2N (M=Fe, Co, Ni), the limiting potential (UL) is less negative than that of the Ru(0001) surface and has the ability to suppress the competitive hydrogen evolution reaction (HER). Among them, Fe3@C2N is suggested to be the most promising candidate for NRR with high thermal stability, strong N2 adsorption ability, low limiting potential, and good NRR selectivity. The concepts of trimetallic sites and alkaline earth metal promoters in this work provide theoretical guidance for the rational design of atomically active sites in electrocatalytic NRR.
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In recent years, with the continuous progress of DNA extraction and detection technology, cell-free DNA(cfDNA)has been widely used in the life science field, and its potential application value in forensic identification is becoming more and more obvious. This paper reviews the concept, formation mechanism, and classification of cfDNA, etc., and describes the latest research progress of cfDNA in personal identification of crime scene touch DNA samples and non-invasive prenatal paternity testing (NIPPT). Meanwhile, this paper summarizes the potential application of cfDNA in injury inference, and discusses the advantages and disadvantages of common cfDNA analysis methods and techniques, and its application prospects, to provide a new idea for the wide application of cfDNA in the field of forensic science.
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Ácidos Nucleicos Libres de Células , Embarazo , Femenino , Humanos , Ácidos Nucleicos Libres de Células/genética , Paternidad , Ciencias Forenses , Tacto , ADN/genéticaRESUMEN
BACKGROUND: Postoperative complications are important factors affecting the survival time and quality of life of patients undergoing radical gastrectomy. AIM: To investigate and compare the anesthetic effects of intravenous general anesthesia combined with epidural anesthesia or ultrasound-guided bilateral transversus abdominal plane block (TAPB) in gastric cancer patients undergoing laparoscopic radical gastrectomy. METHODS: The clinical data of 85 patients who underwent laparoscopic radical gastrectomy in our hospital from December 2020 to January 2023 were retrospectively collected and divided into a TAPB group (n = 45) and epidural anesthesia group (n = 40) according to the different anesthesia and analgesia programs used. The TAPB group received general anesthesia combined with TAPB, and the epidural anesthesia group received general anesthesia combined with epidural anesthesia. The pain status, cognitive status, intestinal barrier indicators, recovery quality, and incidence of complications were compared between the two groups. RESULTS: Compared with the epidural anesthesia group, the TAPB group's visual analog scale scores were significantly lower 6 h, 12 h, 24 h and 48 h after surgery (P < 0.05). The incidence of postoperative cognitive dysfunction (POCD) in the TAPB group was significantly lower than that in the epidural anesthesia group, and the Mini-mental State Examination score 24 h after surgery was significantly higher in the TAPB group than the epidural anesthesia group (P < 0.05). The levels of diamine oxidase and plasma D-lactate were significantly lower in the TAPB group than the epidural anesthesia group 24 h after surgery (P < 0.05). The agitation score and the incidence of agitation during recovery were significantly lower in the TAPB group than epidural anesthesia group (P < 0.05). The total incidence of postoperative complications in the TAPB group was 4.44%, significantly lower than the 20.00% in the epidural anesthesia group (P < 0.05). CONCLUSION: Compared with epidural anesthesia combined with general anesthesia, TAPB combined with general anesthesia had a good analgesic effect in laparoscopic radical gastrectomy and can further reduce the incidence of POCD and postoperative complications, improve the levels of intestinal barrier indicators, and improve postoperative recovery quality.
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Catalysts with heteronuclear metal active sites may have high performance in the nitrogen reduction reaction (NRR), and the in-depth understanding of the reaction mechanisms is crucial for the design of related catalysts. In this work, the dissociative adsorption of N2 on heteronuclear trimetallic MFe2 and M2 Fe (M=V, Nb, and Ta) clusters was studied with density functional theory calculations. For each cluster, two reaction paths were studied with N2 initially on M and Fe atoms, respectively. Mayer bond order analysis provides more information on the activation of N-N bonds. M2 Fe is generally more reactive than MFe2 . The coordination mode of N2 on three metal atoms can be end-on: end-on: side-on (EES) for both MFe2 and M2 Fe. In addition, a unique end-on: side-on: side-on (ESS) coordination mode was found for M2 Fe, which leads to a higher degree of N-N bond activation. Nb2 Fe has the highest reactivity towards N2 when both the transfer of N2 and the dissociation of N-N bonds are taken into account, while Ta-containing clusters have a superior ability to activate the N-N bond. These results indicate that it is possible to improve the performance of iron-based catalysts by doping with vanadium group metals.
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Hierro , Niobio , Adsorción , NitrógenoRESUMEN
It is of great importance to find catalysts for the nitrogen reduction reaction (NRR) with high stability and reactivity. A series of M3 clusters (M = Ti, Zr, V, and Nb) supported on sumanene (C21H12) were designed as potential catalysts for the NRR by taking advantage of the high reactivity of trimetallic clusters and the unique geometric and electronic properties of sumanene, a bowl-like organic molecule. Detailed mechanisms of NîN bond cleavage on C21H12-M3 were investigated by DFT calculations and compared with those on bare M3 clusters. M3 in the sumanene bowl is very stable with large binding energies, which prohibits the cohesion of M3 into M6. In the bowl, M3 has a (quasi-) equilateral triangle structure with lengthened M-M bonds, which is particularly beneficial to the N2 transfer process on Ti3 and V3 clusters. The N-N bond can be dissociated by both M3 and C21H12-M3 clusters without the overall energy barriers. A blurring effect is found in which some geometric and electronic properties of different metal types become similar when M3 is supported on the substrate. Our work demonstrates that sumanene is a suitable substrate to support M3 in the activation of N2 with enhanced stability and maintained a high level of reactivity compared to bare M3.
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XueBiJing is an intravenous five-herb injection used to treat sepsis in China. The study aimed to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS)- or liquid chromatography-ultraviolet (LC-UV)-based assay for quality evaluation of XueBiJing. Assay development involved identifying marker constituents to make the assay therapeutically relevant and building a reliable one-point calibrator for monitoring the various analytes in parallel. Nine marker constituents from the five herbs were selected based on XueBiJing's chemical composition, pharmacokinetics, and pharmacodynamics. A selectivity test (for "similarity of response") was developed to identify and minimize interference by non-target constituents. Then, an intercept test was developed to fulfill "linearity through zero" for each analyte (absolute ratio of intercept to C response, <2%). Using the newly developed assays, we analyzed samples from 33 batches of XueBiJing, manufactured over three years, and found small batch-to-batch variability in contents of the marker constituents (4.1%-14.8%), except for senkyunolide I (26.5%).
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The front cover artwork is provided by Prof. Xun-Lei Ding's group at North China Electric Power University (NCEPU). The image shows the cleavage of the triple bond of a dinitrogen molecule on trinuclear metal clusters with sulfide ligands, which is the critical step in nitrogen reduction reactions (NRR). Read the full text of the Research Article at 10.1002/cphc.202200124.
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The reaction of N2 with trinuclear niobium and tungsten sulfide clusters Nb3 Sn and W3 Sn (n=0-3) was systematically studied by density functional theory calculations with TPSS functional and Def2-TZVP basis sets. Dissociations of N-N bonds on these clusters are all thermodynamically allowed but with different reactivity in kinetics. The reactivity of Nb3 Sn is generally higher than that of W3 Sn . In the favorite reaction pathways, the adsorbed N2 changes the adsorption sites from one metal atom to the bridge site of two metal atoms, then on the hollow site of three metal atoms, and at that place, the N-N bond dissociates. As the number of ligand S atoms increases, the reactivity of Nb3 Sn decreases because of the hindering effect of S atoms, while W3 S and W3 S2 have the highest reactivity among four W3 Sn clusters. The Mayer bond order, bond length, vibrational frequency, and electronic charges of the adsorbed N2 are analyzed along the reaction pathways to show the activation process of the N-N bond in reactions. The charge transfer from the clusters to the N2 antibonding orbitals plays an essential role in N-N bond activation, which is more significant in Nb3 Sn than in W3 Sn , leading to the higher reactivity of Nb3 Sn . The reaction mechanisms found in this work may provide important theoretical guidance for the further rational design of related catalytic systems for nitrogen reduction reactions (NRR).
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Activation of N2 on anionic trimetallic V3-x Tax C4- (x=0-3) clusters was theoretically studied employing density functional theory. For all studied clusters, initial adsorption of N2 (end-on) on one of the metal atoms (denoted as Siteâ 1) is transferred to an of end-on: side-on: side-on coordination on three metal atoms, prior to N2 dissociation. The whole reaction is exothermic and has no global energy barriers, indicating that the dissociation of N2 is facile under mild conditions. The reaction process can be divided into two processes: N2 transfer (TRF) and N-N dissociation (DIS). For V-series clusters, which has a V atom on Siteâ 1, the rate-determining step is DIS, while for Ta-series clusters with a Ta on Siteâ 1, TRF may be the rate-determining step or has energy barriers similar to those of DIS. The overall energy barriers for heteronuclear V2 TaC4- and VTa2 C4- clusters are lower than those for homonuclear V3 C4- and Ta3 C4- , showing that the doping effect is beneficial for the activation and dissociation of N2 . In particular, V-Ta2 C4- has low energy barriers in both TRF and DIS, and it has the highest N2 adsorption energy and a high reaction heat release. Therefore, a trimetallic heteronuclear V-series cluster, V-Ta2 C4- , is suggested to have high reactivity to N2 activation, and may serve as a prototype for designing related catalysts at a molecular level.
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Metales , Aniones , Catálisis , Metales/químicaRESUMEN
XueBiJing is an intravenous five-herb injection used to treat sepsis in China.The study aimed to develop a liquid chromatography-tandem mass spectrometry(LC-MS/MS)-or liquid chromatography-ultraviolet(LC-UV)-based assay for quality evaluation of XueBiJing.Assay development involved identifying marker constituents to make the assay therapeutically relevant and building a reliable one-point cali-brator for monitoring the various analytes in parallel.Nine marker constituents from the five herbs were selected based on XueBiJing's chemical composition,pharmacokinetics,and pharmacodynamics.A selectivity test(for"similarity of response")was developed to identify and minimize interference by non-target constituents.Then,an intercept test was developed to fulfill"linearity through zero"for each analyte(absolute ratio of intercept to C response,<2%).Using the newly developed assays,we analyzed samples from 33 batches of XueBiJing,manufactured over three years,and found small batch-to-batch variability in contents of the marker constituents(4.1%-14.8%),except for senkyunolide I(26.5%).
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Adsorption of N2 on Mo6 S8 q _Vx clusters (x=0, 1, 2; q=0, ±1) were systematically studied by density functional theory calculations with dispersion corrections. It was found that the N2 can be chemisorbed and undergo non-dissociative activation on single or double metal atoms. The adsorption and activation are influenced by metal types (V or Mo), N2 coordination modes and charge states of the clusters. Particularly, anionic Mo6 S8 - _V2 clusters have remarkable ability to fix and activate N2 . In Mo6 S8 - _V2 , two V atoms prefer to adsorb on two adjacent S-Mo-S hollow sites, leading to the formation of a supported V V unit. The N2 is bridged side-on coordinated with these two V atoms with high adsorption energy and significant charge transfer. The bond order, bond length and vibration frequency of the adsorbed N2 are close to those of a N-N single bond.
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AIM: To determine the efficacy of Internet-based interventions in decreasing the prevalence of postpartum depression in perinatal women. DESIGN: This review was conducted according to the standards outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. METHODS: We performed a systematic meta-analysis of randomized controlled trials on the efficacy of Internet-based interventions for postpartum depression. Studies (2008-2018) were identified through a search conducted on PubMed, EMBASE and the Cochrane Library. Risk ratios or weighted mean differences with 95% confidence intervals were calculated using a fixed-effects model or a random-effects model. Stata software 11.0 was used to perform the meta-analysis. RESULTS: Most of the seven eligible studies were randomized controlled trials. The random-effects model indicated that Internet-based interventions significantly improved postpartum depression (d = 0.642, N = 7). Attrition rates ranged from 4.5%-86.9% and from 0%-87.1% for the intervention and control groups, respectively.
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Depresión Posparto , Intervención basada en la Internet , Depresión Posparto/epidemiología , Femenino , Humanos , Parto , EmbarazoRESUMEN
Stoichiometric (MoS2)n clusters (n = 1-6) were systematically studied by density functional theory calculations with hybrid B3LYP and pure GGA PW91 functionals. The most stable structures of these clusters were obtained by global optimizations with a genetic algorithm. A triangle of Mo3 capped with a S atom was found to be a favourite building block, which can construct the most stable structures (or at least candidates) for n = 3-6 clusters. These types of structures can be viewed as fragments of MoS2 monolayer with the 1T phase, which is an important phase that has unique reactivity and conductivity properties. Electronic structures were analyzed by means of density of states and frontier molecular orbitals (FMOs), which suggest that both Mo and S contribute to the FMOs below the Fermi energy while Mo atoms contribute more toward the unoccupied FMOs.
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Effective communication among healthcare professionals in the intensive care unit (ICU) is a particular imperative, with accurate and efficient interdisciplinary communication being a critical prerequisite for high-quality care. Nurses and physicians are highly important parts of the healthcare system workforce. Thus, identifying strategies that would improve communication between these two groups can provide evidence for practical improvement in the ICU, which will ultimately improve patient outcomes. This integrative literature review aimed to identify interventions that improve communication between nurses and physicians in ICUs. Three databases (Medline, CINAHL, and Science Direct) were searched between September 2014 and June 2016 using 11 search terms, namely, nurse, doctor, physician, resident, clinician, ICU, intensive care unit, communication, teamwork, collaboration, and relationship. A manual search of the reference lists of found papers was also conducted. Eleven articles met the inclusion criteria. These studies reported on the use of communication tools/checklists, team training, multidisciplinary structured work shift evaluation, and electronic situation-background-assessment-recommendation documentation templates to improve communication. Although which intervention strategies are most effective remains unclear, this review suggests that these strategies improve communication to some extent. Future studies should be rigorously designed and outcome measures should be specific and validated to capture and reflect the effects of effective communication.
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The adsorption behaviour of a single O atom on Aunq clusters (n = 1-8, q = 0, ±1) was systematically investigated by DFT calculations. Both hybrid and pure GGA functionals (B3LYP and PBE) were used to provide reliable conclusions. The most stable structures of AunOq clusters were obtained by using global optimizations with a genetic algorithm. Cationic clusters tend to become three-dimensional for large clusters, as for Au8O+. The binding of O in AunOq clusters is quite strong, especially in the anionic clusters. The O atom can be bound to one, two, or three Au atoms, obtaining nearly one electron from gold atoms. Similarities have been found between AunOq and Aun+1q in terms of geometric structures and binding energies. Frontier molecular orbitals and the distribution of unpaired spin density on the O atom were discussed, both of which have a close relationship with the activity of the clusters.
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The present article reports a novel biosensor for organophosphorus pesticides based on fluorescence resonance energy transfer (FRET) between nitrogen-doped carbon dots (NC-dots) and gold nanoparticles (AuNPs). The effective NC-dots/AuNPs assembly through the Au-N interaction results in good fluorescence quenching. Active acetylcholinesterase (AChE) catalyzes the hydrolysis of acetylthiocholine into -SH containing thiocholine to replace the NC-dots and trigger the aggregation of AuNPs. In the presence of paraoxon, the activity of AChE is inhibited, and thus preventing the generation of thiocholine, causing fewer NC-dots to be replaced. As a consequence, the fluorescence intensity gradually decreases with increasing amount of paraoxon. This biosensor does not require any complex synthesis or modification, and the results show a wide detection range of from 10(-4) to 10(-9) g/L with a detection limit of 1.0 × 10(-9) g/L (3.6 × 10(-12) mol/L). Two linear response regions have been reported with a turning point at about 10(-6) g/L and three different factors that would influence the response behavior. These phenomena discussed in detail so as to explain the special response mechanism.
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Carbono/química , Transferencia Resonante de Energía de Fluorescencia/métodos , Oro/química , Nanopartículas del Metal/química , Nitrógeno/química , Compuestos Organofosforados/análisis , Puntos Cuánticos/química , Técnicas Biosensibles , Jugos de Frutas y Vegetales/análisis , Límite de Detección , Malus/química , Compuestos Organofosforados/química , Plaguicidas/análisis , Plaguicidas/químicaRESUMEN
Special AT-rich sequence-binding protein-1 (SATB1) is critical for genome organizer that reprograms chromatin organization and transcription profiles, and associated with tumor growth and metastasis in several cancer types. Many studies suggest that SATB1 overexpression is an indicator of poor prognosis in various cancers, such as breast cancer, malignant cutaneous melanoma, and liver cancer. However, their expression patterns and function values for adult T cell leukemia (ATL) are still largely unknown. The aim of this study is to examine the levels of SATB1 in ATL and to explore its function and mechanisms in Jurkat cell line. Here, we reported that SATB1 expressions were decreased in ATL cells (p < 0.001) compared with normal controls. Knockdown of SATB1 expression significantly enhanced invasion of Jurkat cell in vitro. Furthermore, knockdown of SATB1 gene enhances ß-catenin nuclear accumulation and transcriptional activity and thus may increase the invasiveness of Jurkat cell through the activation of Wnt/ß-catenin signaling pathway in vitro.
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Regulación Neoplásica de la Expresión Génica , Proteínas de Unión a la Región de Fijación a la Matriz/fisiología , Proteínas de Neoplasias/fisiología , Vía de Señalización Wnt/fisiología , Adulto , Línea Celular Tumoral , Regulación hacia Abajo , Perfilación de la Expresión Génica , Humanos , Células Jurkat , Leucemia-Linfoma de Células T del Adulto/sangre , Leucemia-Linfoma de Células T del Adulto/genética , Leucemia-Linfoma de Células T del Adulto/patología , Proteínas de Unión a la Región de Fijación a la Matriz/antagonistas & inhibidores , Proteínas de Unión a la Región de Fijación a la Matriz/biosíntesis , Proteínas de Unión a la Región de Fijación a la Matriz/genética , Invasividad Neoplásica , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Interferencia de ARN , ARN Mensajero/biosíntesis , ARN Neoplásico/biosíntesis , ARN Interferente Pequeño/genética , Vía de Señalización Wnt/genéticaRESUMEN
A novel 2-dimensional graphene analog molybdenum disulfide/multi-walled carbon nanotube (MoS2/MWCNT) was synthesized by a simple hydrothermal method to achieve excellent electrochemical properties. An ultrasensitive electrochemical DNA biosensor was subsequently constructed by assembling a thiol-tagged DNA probe on a MoS2/MWCNT and gold nanoparticle (AuNP)-modified electrode that has already been coupled with glucose oxidase (GOD). In this work, GOD was used as a redox marker. The heteronanostructure formed on the biosensor surface appeared relatively good conductor for accelerating the electron transfer, while the modification of GOD and AuNPs provided multiple signal amplification for electrochemical biosensing. The multiple signal amplification strategy produced an ultrasensitive electrochemical detection of DNA down to 0.79 fM with a linear range from 10 fM to 10(7)fM, and appeared high selectivity to differentiate three-base mismatched DNA and one-base mismatched DNA. The developed approach provided a simple and reliable method for DNA detection with high sensitivity and specificity, and would open new opportunities for sensitive detection of other biorecognition events.
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Conductometría/instrumentación , ADN/análisis , ADN/genética , Nanopartículas del Metal/química , Molibdeno/química , Nanotubos de Carbono/química , Técnicas de Amplificación de Ácido Nucleico/instrumentación , Técnicas Biosensibles/instrumentación , Disulfuros/química , Diseño de Equipo , Análisis de Falla de Equipo , Oro , Nanopartículas del Metal/ultraestructura , Microquímica/instrumentación , Nanocompuestos/química , Nanocompuestos/ultraestructura , Nanotubos de Carbono/ultraestructura , Análisis de Secuencia por Matrices de Oligonucleótidos/instrumentación , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The purpose of this study was to construct a HA-1-DC nucleic acid vaccine and to induce anti-leukemia effect after hematopoietic stem cell transplantation (HSCT). The dendritic cells (DCs) were generated from HSCT donors in vitro, and its immunologic activity was studied by using flow cytometry and mix lymphocyte reaction. HA-1 gene was electroporated into the cultured DCs to construct a DC nucleic acid vaccine. After transfecting for 48 hours, the expression of HA-1 protein was detected by Western blot. The DCs were cultured with isogenic lymphocytes to induce specific cytotoxic T lymphocytes (CTLs). The cytotoxicity of the CTLs was detected by LDH assay. The results showed that the DCs derived from peripheral blood monocytes (PBMCs) expressed the DC phenotype, and were effective in stimulating proliferation of the allogenic lymphocytes. After electroporating for 48 hours, HA-1 protein was detected by Western blot. The cytotoxity of inducing CTLs was higher than that in the control group. It is concluded that the minor histocompatibility antigen HA-1 can be considered as a target of immunotherapy against leukemia after HSCT.
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Vacunas contra el Cáncer/biosíntesis , Leucemia/inmunología , Antígenos de Histocompatibilidad Menor/genética , Oligopéptidos/genética , Linfocitos T Citotóxicos/inmunología , Vacunas de ADN/biosíntesis , Vacunas contra el Cáncer/genética , Vacunas contra el Cáncer/inmunología , Células Cultivadas , Células Dendríticas/citología , Células Dendríticas/inmunología , Electroporación , Enfermedad Injerto contra Huésped/prevención & control , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Leucemia/terapia , Antígenos de Histocompatibilidad Menor/inmunología , Oligopéptidos/inmunología , Transfección , Vacunas de ADN/genética , Vacunas de ADN/inmunologíaRESUMEN
The purpose of this study was to establish a SYBR Green I real-time quantitative RT-PCR method for investigating the correlation between CML28 mRNA expression levels and relapse of leukemia after allo-hematopoietic stem cell transplantation (HSCT). pcDNA3.1HisA-CML28 plasmid had been constructed as the standard template. Serial monitoring of CML28 mRNA levels by SYBR Green I real-time quantitative RT-PCR technique was performed in 14 patients, including 10 patients with CML and 3 patients with AML, 1 patient with Ph(+) ALL. The results showed that the sensitivity of the established method was at 10(-4) (0.05 ng) level, with interassay variation and intraassay variation of standard samples both below 10%. The CML28 was highly expressed in AML and CML-BP or AP. CML28 level in newly diagnosed group was (6.58 +/- 2.34) x 10(-2), in pre-conditioning regimen group was (2.19 +/- 0.32) x 10(-2), in group that 1 month after HSCT was (1.35 +/- 1.28) x 10(-2), in group that 3 months after HSCT was (4.57 +/- 6.39) x 10(-3). CML28 can be detected 3 months after HSCT in 1 patient with CML-CP and 3 patients with CML-AP or BC. 2 of them with low level (<2 x 10(-2)) survived without relapse, the other 2 case with high level (>2 x 10(-2)) relapsed within one year, 1 case died and 1 case received the second time HSCT, CML28 level decreased rapidly after HSCT, but still higher than 2 x 10(-2) and relapse has taken place. The conclusions was made that CML28 mRNA level is obviously correlated with the development of leukemia. Serial quantification of CML28 mRNA levels are necessary for HSCT recipients, and more informative than a single detection. Using of this assay to evaluate MRD in the patients received HSCT is helpful for prediction of relapse.