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Heat shock transcription factors (Hsfs) play important roles in plant developmental regulations and various stress responses. In present study, 46 Hsf genes in peanut ( AhHsf ) were identified and analyzed. The 46 AhHsf genes were classed into three groups (A, B, and C) and 14 subgroups (A1-A9, B1-B4, and C1) together with their Arabidopsis homologs according to phylogenetic analyses, and 46 AhHsf genes unequally located on 17 chromosomes. Gene structure and protein motif analysis revealed that members from the same subgroup possessed similar exon/intron and motif organization, further supporting the results of phylogenetic analyses. Gene duplication events were found in peanut Hsf gene family via syntenic analysis, which were important in Hsf gene family expansion in peanut. The expression of AhHsf genes were detected in different tissues using published data, implying that AhHsf genes may differ in function. In addition, several AhHsf genes ( AhHsf5 , AhHsf11 , AhHsf20 , AhHsf24 , AhHsf30 , AhHsf35 ) were induced by drought and salt stresses. Furthermore, the stress-induced member AhHsf20 was found to be located in nucleus. Notably, overexpression of AhHsf20 was able to enhance salt tolerance. These results from this study may provide valuable information for further functional analysis of peanut Hsf genes., Competing Interests: CG was employed by Kunming Branch of Yunnan Provincial Tobacco Company. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Zhang, Guo, Zhao, Li, Mou, Sun, Wang, Yuan, Li, Cong and Shan.)

The MYB members play important roles in development, metabolism, and stress tolerance in plants. In the current study, a total of 246 tobacco R2R3-MYB transcription factors were identified and systemically analyzed from the latest genome annotation. The newly identified tobacco members were divided into 33 subgroups together with the Arabidopsis members. Furthermore, 44 NtMYB gene pairs were identified to arise from duplication events, which might lead to the expansion of tobacco MYB genes. The expression patterns were revealed by transcriptomic analysis. Notably, the results from phylogenetic analysis, synthetic analysis, and expression analysis were integrated to predict the potential functions of these members. Particularly, NtMYB102 was found to act as the homolog of AtMYB70 and significantly induced by drought and salt treatments. The further assays revealed that NtMYB102 had transcriptional activities, and the overexpression of the encoding gene enhanced the drought and salt stress tolerance in transgenic tobacco. The results of this study may be relevant for future functional analyses of the MYB genes in tobacco., Competing Interests: XL, GW, LC, JG and WP were employed by China Tobacco Hunan Industrial Co., Ltd. CG was employed by Yunnan Provincial Tobacco Company. GW was employed by Yuxizhongyan Tobacco Seed Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Li, Guo, Li, Wang, Yang, Chen, Hu, Sun, Gao, Yang, Pu and Wen.)

Stretchable wireless power is in increasingly high demand in fields such as smart devices, flexible robots, and electronic skins. Thermoelectric devices are able to convert heat into electricity due to the Seebeck effect, making them promising candidates for wearable electronics. Therefore, high-performance conductive polymer-based composites are urgently required for flexible wearable thermoelectric devices for the utilization of low-grade thermal energy. In this review, mechanisms and optimization strategies for polymer-based thermoelectric composites containing fillers of different architectures will be introduced, and recent advances in the development of such thermoelectric composites containing 0- to 3-dimensional filler components will be presented and outlooked.

The pectin methylesterases (PMEs) play multiple roles in regulating plant development and responses to various stresses. In our study, a total of 121 PME genes were identified in the tobacco genome, which were clustered into two groups based on phylogenetic analysis together with Arabidopsis members. The investigations of gene structure and conserved motif indicated that exon/intron and motif organizations were relatively conserved in each group. Additionally, several stress-related elements were identified in the promoter region of these genes. The survey of duplication events revealed that segmental duplications were critical to the expansion of the PME gene family in tobacco. The expression profiles analysis revealed that these genes were expressed in various tissues and could be induced by diverse abiotic stresses. Notably, NtPME029 and NtPME043 , were identified as homologues with AtPME3 and AtPME31 , respectively. Furthermore, NtPME029 was highly expressed in roots and the over-expression of the NtPME029 gene could promote the development of roots. While NtPME043 could be induced by salt and ABA treatments, and the over-expression of the NtPME043 gene could significantly enhance the salt-stress tolerance in tobacco. Overall, these findings may shed light on the biological and functional characterization of NtPME genes in tobacco., Competing Interests: JS, ZT, SL, JW, ZH, HC, and RX were employed by China Tobacco Jiangsu Industrial Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sun, Tian, Li, Li, Li, Wang, Hu, Chen, Guo, Xie and Xu.)

With increasing popularity and great application prospects of flexible wearable electronics, organic thermoelectric (TE)materials have become one hotspot in view of energy recycling and environment protection. However, diversifying application scenarios and frequent movements impose inevitable damage to materials. Herein, the polyethylene (PE) matrix is used in compositing with poly(3,4-ethylenedioxythiophene) and single-walled carbon nanotubes, forming a unique conductive penetration network and endowing the composites with a maximal room-temperature power factor of 158.81 μW m -1 K -2 with 20 wt % of PE. The introduction of PE not only reduces thermal conductivity (out-of-plane) but also provides the composites with self-healing and good mechanical properties. The compounding method and penetration structure reported in this work are universal and enlightening in developing highly efficient TE composites with cost-effectiveness and good comprehensive properties for low-grade waste heat utilization.

Leaf senescence is a highly coordinated process and has a significant impact on agriculture. Plant peptides are known to act as important cell-to-cell communication signals that are involved in multiple biological processes such as development and stress responses. However, very limited number of peptides has been reported to be associated with leaf senescence. Here, we report the characterization of the INFLORESCENCE DEFICIENT IN ABSCISSION-LIKE6 (IDL6) peptide as a regulator of leaf senescence. The expression of IDL6 was up-regulated in senescing leaves. Exogenous application of synthetic IDL6 peptides accelerated the process of leaf senescence. The idl6 mutant plants showed delayed natural leaf senescence as well as senescence included by darkness, indicating a regulatory role of IDL6 peptides in leaf senescence. The role of IDL6 as a positive regulator of leaf senescence was further supported by the results of overexpression analysis and complementation test. Transcriptome analysis revealed differential expression of phytohormone-responsive genes in idl6 mutant plants. Further analysis indicated that altered expression of IDL6 led to changes in leaf senescence phenotypes induced by ABA and ethylene treatments. The results from this study suggest that the IDL6 peptide positively regulates leaf senescence in Arabidopsis thaliana ., Competing Interests: XL was employed by China Tobacco Hunan Industrial Co., Ltd. CL was employed by QuJing Tobacco Company. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Guo, Li, Zhang, Wang, Zhang, Wen, Liu, Deng, Chu, Liu and Guo.)

The Catharanthus roseus RLK1-like (CrRLK1L) family is involved in the regulation of plant reproduction, growth and development, cell wall integrity sensing, as well as responses to both biotic and abiotic stress conditions. Extraordinary progress has been made in elucidating the CrRLK1L family receptor kinases-mediated signaling pathway, while limited research addressed the functions of CrRLK1L proteins in tobacco. In this study, we identified and analyzed 48 NtCrRLK1L members from the tobacco genome. The newly identified NtCrRLK1L members were divided into seven groups together with the Arabidopsis CrRLK1L members. The syntenic analysis revealed that four pairs of NtCrRLK1L genes were predicted to have arisen from segmental duplication events. Expression profiling showed that the NtCrRLK1L genes were expressed in various tissues, and most NtCrRLK1L genes were induced by salt and drought stress conditions. Notably, NtCrRLK1L47 was upregulated under drought and salinity stresses, and the NtCrRLK1L47-GFP fusion protein was located in the cell membrane. Furthermore, overexpression of the NtCrRLK1L47 gene enhanced the salt tolerance in tobacco seedlings., Competing Interests: XL, JG, and WP were employed by China Tobacco Hunan Industrial Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Li, Guo, Wang, Li, Cai, Wu, Li, Yang, Guo, Gao, Wen and Pu.)

The NAC (NAM, ATAF1/2, and CUC2) family acts as one of the largest families of the transcription factor in the plant kingdom and was revealed to function as the important regulators in various environmental stresses. However, a few studies were reported about the biofunctions of the NAC transcription factor in tobacco. In the current study, we characterized a novel NAC transcription factor encoding the gene NtNAC053 in tobacco, which was significantly up-regulated when exposed to salt and drought treatments. The results of cis -acting elements analysis suggested that the promoter region of NtNAC053 gene possesses a number of stress-responsive elements, and this gene could be induced by exogenous abscisic acid (ABA) treatment. Moreover, the NtNAC053-GFP fusion protein was localized in the cell nucleus and possessed a transactivation domain in its C-terminal, implying that NtNAC053 may undertake as a transcriptional activator in tobacco. Notably, the overexpression of NtNAC053 in tobacco resulted in hypersensitivity to ABA treatment. Furthermore, these overexpression lines showed significantly enhanced tolerances to drought and salt stresses. Under salt and drought stresses, these overexpression lines possessed higher superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) activities. Interestingly, the expressions of putative stress-related genes, including NtCOR15A , NtRAB18 , NtDREB1A , NtERF5 , NtKAT2 , and NtERD11 , were up-regulated in these overexpression lines when subjected to salt and drought stresses. The clues provided in our study suggested that the NtNAC053 gene encodes a novel NAC transcription factor and could confer the drought and salt stress tolerances by inspiring the downstream stress-responsive genes and antioxidant system in tobacco., Competing Interests: XL, YW, WP, and JG were employed by China Tobacco Hunan Industrial Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Li, Wang, Guo, Sun, Li, Wang, Yang, Pu, Guo, Gao and Wen.)

Background: So far, few approaches have been described to reduce inadvertent injury to structure of the heart and nearby organs in percutaneous pericardiocentesis., Hypothesis: We hypothesized that an in-plane high frequency ultrasound-guided apical approach, performed in the sitting position, would provide additional benefits in terms of feasibility and safety for draining malignant pericardial effusion (MPE)., Methods: The authors selected 53 consecutive patients with moderate or large symptomatic MPE who underwent high frequency ultrasound-guided pericardiocentesis. After the procedure, all patients were followed for 90 days with the main purpose of detecting procedure success, procedure-related complications, and recurrent PE., Results: Procedure success rate for pericardiocentesis was 100%. All patients were placed in the sitting position with their left hands extended above the heads. An apical puncture approach was performed in all cases (100%). The mean duration of catheter drainage was 8.1 ± 3.2 days. The mean initial amount of pericardial fluid drained was 956.3 ± 687.5 ml. Overall, six patients (11%) had recurrent PE; 3 (6%) had repeated percutaneous pericardiocentesis. There was no major complication and minor complications occurred in four patients (8%)., Conclusion: This novel in-plane high frequency US-guided apical approach has several advantages for percutaneous pericardiocentesis of MPE: performed in the sitting position; a benefit for patients with orthopnea; a maximum inserted wide angle to prevent damage to the myocardium; local enlargement of the PE region; high procedure success rate of pericardiocentesis; and excellent clinical outcomes., (© 2021 The Authors. Clinical Cardiology published by Wiley Periodicals LLC.)

The bZIP proteins comprise one of the largest transcription factor families and play important roles in plant growth and development, senescence, metabolic reactions, and stress responses. In this study, 49 bZIP transcription factor-encoding genes ( StbZIP genes) on the potato genome were identified and analyzed. The 49 StbZIP genes, which are located on 12 chromosomes of the potato genome, were divided into 11 subgroups together with their Arabidopsis homologs based on the results of phylogenetic analysis. Gene structure and protein motif analysis revealed that members from the same subgroup often possessed similar exon/intron structures and motif organizations, further supporting the results of the phylogenetic analysis. Syntenic analysis indicated the existence of gene duplication events, which might play an important role in the expansion of the bZIP gene family in potato. Expressions of the StbZIP genes were analyzed in a variety of tissues via RNA-Seq data, suggesting functional diversity. Several StbZIP genes were found to be induced by different stress conditions. For example, the expression of StbZIP25 , the close homolog of AtbZIP36/ABF2, was significantly upregulated by salt stress treatments. The StbZIP25 protein was found to be located in the nucleus and function as a transcriptional activator. Overexpression of StbZIP25 enhanced salt tolerance in Arabidopsis . The results from this study imply potential roles of the bZIP family genes in the stress response of potato., Competing Interests: XL, DW, and LX were employed by China Tobacco Hunan Industrial Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Wang, Guo, Li, Sun, Wang, Xu, Li and Guo.)

The inflorescence deficient in abscission-like ( IDL ) genes have been shown to play critical roles in floral organ abscission, lateral root formation and various stress responses in Arabidopsis . The IDL gene family has been characterized in a number of plant species, while limited information is available about IDL genes of tobacco. In the current study, 15 NtIDL members were identified in the tobacco genome, and were classified into six groups together with IDL members from other species. Evolution analysis suggested that the NtIDL members form group VI might have originated from duplication events. Notably, NtIDL06 shared high similarities with AtIDA in the EPIP sequence, and its encoding gene was highly expressed in the abscission zone of flowers at late developmental stages, implying that NtIDL06 might regulate tobacco flower abscission. In addition, the results from cis -elements analysis of promoters and expression after stress treatments suggested that NtIDL members might be involved in various stress responses of tobacco. The results from this study provide information for further functional analysis related to flower abscission and stress responses of NtIDL genes., Competing Interests: XL was employed by China Tobacco Hunan Industrial Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The handling editor declared a past co-authorship with one of the authors XL., (Copyright © 2021 Guo, Wang, Li, Sun, Zhang, Li and Guo.)

The NAC (NAM, ATAF1/2, and CUC2) transcription factors comprise one of the largest transcription factor families in plants and play important roles in stress responses. However, little is known about the functions of potato NAC family members. Here we report the cloning of a potato NAC transcription factor gene StNAC053 , which was significantly upregulated after salt, drought, and abscisic acid treatments. Furthermore, the StNAC053-GFP fusion protein was found to be located in the nucleus and had a C-terminal transactivation domain, implying that StNAC053 may function as a transcriptional activator in potato. Notably, Arabidopsis plants overexpressing StNAC053 displayed lower seed germination rates compared to wild-type under exogenous ABA treatment. In addition, the StNAC053 overexpression Arabidopsis lines displayed significantly increased tolerance to salt and drought stress treatments. Moreover, the StNAC053-OE lines were found to have higher activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) under multiple stress treatments. Interestingly, the expression levels of several stress-related genes including COR15A, DREB1A , ERD11 , RAB18 , ERF5 , and KAT2 , were significantly upregulated in these StNAC053 -overexpressing lines. Taken together, overexpression of the stress-inducible StNAC053 gene could enhance the tolerances to both salt and drought stress treatments in Arabidopsis , likely by upregulating stress-related genes.

The fabrication of flexible high-performance organic/inorganic thermoelectric (TE) composite films has been a hot spot for researchers in recent years. In this work, dynamic 3-phase interfacial electropolymerization of aniline, together with physical mixing with single-walled carbon nanotubes (SWCNTs), was adopted to prepare polyaniline/SWCNT (PANI/SWCNT) TE composites. The dimethyl sulfoxide (DMSO) added into the electrochemical polymerization system affords strong capability in improving the TE performance of composite films. Moreover, varying loadings of SWCNTs can also conveniently tune the TE performance of composites. Hence, the resultant composites afford the highest power factor (PF) of 236.4 ± 5.9 μW m -1 K -2 at room temperature. This work demonstrates that the introduction of DMSO into the electrolyte and the electrochemical polymerization are highly effective in fabricating high-performance PANI/SWCNT TE composites.

Aim: The aim of this study was to assess the accuracy of post-operative ultrasound examination for predicting wrist radio-cephalic arteriovenous fistula maturity., Methods: All radio-cephalic arteriovenous fistulas performed in our hospital between October 2015 and December 2017 were included in this study. Ultrasound examination of radio-cephalic arteriovenous fistulas was performed 2 weeks post-surgery. Radio-cephalic arteriovenous fistula maturation was defined as successful cannulation of a fistula with two needles, delivery of blood via the access route at a flow rate ⩾200 mL/min for 4 h, and dialysis via fistulae in at least six consecutive sessions., Results: Eighty-two wrist radio-cephalic arteriovenous fistulas were analyzed, of which 13 failed. Cephalic vein diameter >4.285 mm and brachial artery peak systolic velocity >134.75 cm/s were the best post-operative ultrasound predictors of radio-cephalic arteriovenous fistula maturity ( p  < 0.001 and p  = 0.011, respectively). Receiver-operating characteristic curve analysis showed that the sensitivity and specificity of predicting radio-cephalic arteriovenous fistula maturation were 88.4% and 92.3% for cephalic vein diameter (area under the curve = 0.939), respectively, and 82.9% and 76.9% for brachial artery peak systolic velocity (area under the curve = 0.830), respectively. All assessments predicted radio-cephalic arteriovenous fistula maturity (post-operative positive predictive values: cephalic vein diameter = 98.4%, brachial artery peak systolic velocity = 95%) much better than radio-cephalic arteriovenous fistula failure (post-operative negative predictive values: cephalic vein diameter = 60%, brachial artery peak systolic velocity = 45.5%)., Conclusion: Two weeks after surgery, a new wrist radio-cephalic arteriovenous fistula with a cephalic vein diameter >4.285 mm was considered suitable for dialysis. A high-risk arteriovenous fistula failure would benefit from early intervention.

The environmental friendly biomaterial β-cyclodextrin (β-CD) was used for the synthesis of cyclic carbonates from CO₂ with epoxides in the presence of quaternary ammonium salts as co-catalyst. The factors affecting the activity of this binary catalyst system, such as reaction temperature, time, CO₂ pressure and the mole ratio of reactants, were investigated systematically. The excellent yield of cyclic carbonate (100%) was obtained at 130 °C, 3 MPa after 5 h with the catalyst system of β-CD/tetrabutylammonium bromine (TBABr). The catalyst system of β-CD/TBABr can also be applied to a wide substrates of epoxides with good to excellent yield and high selectivity (>99%). Recyclable ability of β-CD/TBABr can also be detected and there was no significant decline in activity after five recycles. Finally, reaction mechanism was proposed based on the reaction results and literatures.

Leucine-rich repeat receptor-like kinases (LRR-RLKs) represent the largest subfamily of receptor-like kinases (RLKs) and play important roles in regulating growth, development, and stress responses in plants. In this study, 246 LRR-RLK genes were identified in the potato ( Solanum tuberosum ) genome, which were further classified into 14 subfamilies. Gene structure analysis revealed that genes within the same subgroup shared similar exon/intron structures. A signature small peptide recognition motif (RxR) was found to be largely conserved within members of subfamily IX, suggesting that these members may recognize peptide signals as ligands. 26 of the 246 StLRR-RLK genes were found to have arisen from tandem or segmental duplication events. Expression profiling revealed that StLRR-RLK genes were differentially expressed in various organs/tissues, and several genes were found to be responsive to different stress treatments. Furthermore, StLRR-RLK117 was found to be able to form homodimers and heterodimers with StLRR-RLK042 and StLRR-RLK052. Notably, the overlapping expression region of StLRR-RLK117 with Solanum tuberosum WUSCHEL ( StWUS ) suggested that the CLV3⁻CLV1/BAM⁻WUS feedback loop may be conserved in potato to maintain stem cell homeostasis within the shoot apical meristem.

Aims: Dysfunction of the host immune system in cancer patients can be due to a number of factors, including lymphocyte apoptosis. Several studies showed that Foxp3+T cells take part in inducing this process by expressing FasL in tumor patients. However, the relationship between apoptosis, CD8+T cells and Foxp3+T cells in HCC patients is still unclear. The present study was designed to investigate the correlation between apoptosis levels and Fas/FasL expression in CD8+T lymphocytes and Foxp3+T cells in patients with HCC., Methods: CD8+T cells and CD3+Foxp3+T cells were tested from peripheral blood of HCC patients and normal controls and subjected to multicolor flow cytometry. The expression of an apoptosis marker (annexin V) and the death receptor Fas in CD8+T cells and FasL in CD3+Foxp3+T cells were evaluated. Serum TGF-β1 levels in patients with HCC were measured by enzyme-linked immunosorbent assay. The relationship between apoptosis and Fas expression, as well as FasL expression in CD3+Foxp3+T cells was then evaluated., Results: The frequency of CD8+T cells binding annexin V and Fas expression in CD8+T cells, were all higher in HCC patients than normal controls and the proportion of apoptotic CD8+T cells correlated with their Fas expression. Serum TGF-β1 levels correlated inversely with CD3+Foxp3+T cells., Conclusions: Fas/FasL interactions might lead to excessive turnover of CD8+T cells and reduce anti-tumor immune responses in patients with HCC. Further investigations of apoptosis induction in Fas+CD8+T cells in vitro are required.

Objective: To study the molecular mechanism of apoptosis of leukemic cells (K562 cells) induced by iron chelating agent deferoxamine (DFO)., Methods: The exponentially growing K562 cells were used (1×10(6)/mL) in this study. The K562 cells were treated with different concentrations of DFO (10, 50 and 100 mmol/L), DFO+FeCl3 (10 μmol/L each) or normal saline (blank control). The cellular labile iron pool was measured with a fluorimetric assay using the metalsensitive probe calcein-AM. The viable count and cell viability were determined by typanblue assay. Cell apoptosis was determined by morphological study and flow cytometry assay. Caspase-3 activity in K562 cells was detected by colorimetry., Results: After DFO treatment, the cellular labile iron pool and the viability of K562 cells were reduced and the cell apoptosis increased in a time- and dose-dependent manner compared with the blank control group. The apoptosis rate of K562 cells in the DFO+FeCl3 treatment group was not significantly different from that in the blank control group. The caspase-3 activity in K562 cells increased significantly 24 hrs after 50 and 100 μmmol DFO treatment when compared with the blank control group (P<0.01). There was a negative correlation between cellular labile iron pool and caspase-3 activity of K562 cells (r=-0.894, P<0.05)., Conclusions: DFO induces apoptosis of leukemic cells possibly through decreasing cellular labile iron pool and increasing caspase-3 activity of the cells.

To explore a rapid and easy method to detect labile iron of pool (LIP) in cells, HL-60 and K562 cells were cultured at a concentration 1 x 10(6)/ml in RPMI 1640 containing 10% heat-inactivated fetal bovine serum. The iron deprivation was induced by adding desferrioxamine (DFO) 10 - 100 micromol/L for 0 - 48 hours. The intracellular LIP was measured by probe calcein-AM. Calcein fluorescence was monitored in 1420 multilabel counter. The results indicated that when HL-60 and K562 cells were incubated with different concentrations of DFO, the calcein fluorescence intensity was higher than that of control group at 12, 24 and 48 hours (P < 0.05). Fluorescence value of representing LIP in DFO groups was lower than that in the control group. In conclusion, DFO can decrease LIP in leukemia cells. The approach used in this study may provide a simple and reliable method for detection of intracellular iron homeostasis.

Objective: 12-0-tetradecanoylphorbol-13 acetate (TPA) plays an important role in precipitating cell differentiation for various tumor cells, especially leukemic cells. Changes of many genes may be involved in this process. The purpose of this study was to observe the relationship between the EGR1mRNA expression and cell differentiation during TPA-induced K562 cell differentiation., Methods: Incubation of human K562 cells in vitro was applied to cultivate K562 cells. The cells were treated in two different ways. K562 cells of experiment group were treated with TPA and those of control group were treated without TPA. Using morphology (Wright's staining and NSE staining) and flow cytometry (FCM), the investigators observed the differentiation characteristics of K562 cells, cell-cycle and the differentiation antigen expressions of CD33 and CD14 on cell membranes. RT-PCR was carried out to assay EGR1 mRNA expression., Results: After treated with TPA for 7 d, the morphology of K562 cells obviously tended to mature differentiation, like monocytes. The differentiation rate of induced K562 cells was up to 95% in experiment group and 4.5% in control group, respectively. Using SPSS software, the above result showed statistical significance (P < 0.01). Using NSE staining, K562 cells showed positive reaction. Some of them were densely stained. The positive rate was up to 86%. More than half of the positive cells could be inhibited by NaF. The inhibiting rate of NaF was up to 58.72%, showing statistical difference when compared with that of control group. FCM analysis showed that most of K562 cells stimulated by TPA underwent G1/S phase cell-cycle arrest. The composing rate of cell-cycle in TPA-treated group showed that (53.7 +/- 1.25)% of cells were at G0 + G1 phase and (44.3 +/- 1.32)% were at S phase (P < 0.05). The level of CD33 expression on cell membranes was mildly decreased from 0.997% to 0.893% (P > 0.05). However, the level of CD14 expression was significantly increased from 0.049% to 0.387% (P < 0.05)., Conclusion: K562 cells could express EGR1mRNA during TPA-induced differentiation, which suggested that EGR1mRNA might participate in the process of K562 cells differentiating into monocyte/macrophages, and might play an important role in precipitating and maintaining cell differentiation for leukemic cells.

Objective: To express the cloned gene glycoprotein I (gpI) of varicella-zoster virus (VZV), Beijing VZV 84-7 strain in insect cells and to purify its expression product., Methods: The gene coding for gpI of VZV was amplified from viral DNA by PCR and cloned into baculovirus transfer vector (pBacPAK9), and recombinant transfer vector plasmid pBacVZVgpI was obtained. The inserted gpI gene in the pBacVZVgpI was sequenced. Insect cells Sf 9 were co-transfected with the recombinant transfer vector plasmid pBacVZVgpI and wild type linear baculovirus BacPAK6 (digested with Bsu36I) DNA. The recombinant baculoviruses containing the VZV 84-7 gpI gene was isolated through several rounds of limited dilution. Recombinant protein gpI was expressed in insect cells Sf 9, postinfected with recombinant baculoviruses. The expressed recombinant gpI was purified by lectin affinity chromatography and its antigenicity and immunogenicity were investigated., Results: The gene coding for gpI of VZV was obtained by PCR and the gpI gene of pBacPAK9 was confirmed by DNA sequencing. The recombinant gpI was expressed in insect cells Sf 9, post-infected with recombinant baculovirus and identified by SDS-PAGE and western blotting, with its product in cell culture reaching the peak in 72 hours and with a molecular mass of 58 kd and 70 kd, the same as theoretical values. Results of immunoassay with cell lysates infected by recombinant baculoviruses indicated that recombinant protein expressed in insect cells had ability of eliciting specific antibodies against native VZV in mice and complement-dependent neutralizing antibodies. The purified recombinant gpI gave a product with a purity of more than 80%. ELISA and Western-blot analysis demonstrated that purified protein had specific VZV antibody-binding activity. This suggested that the recombinant gpI expressed in insect cells had the same biological characteristics as its native counterpart., Conclusion: Baculovirus-insect cells could be used to express the gene of VZV gpI, which could provide a basis for quantitative analysis of VZV antigen, and preparation of its subunit vaccine.