Advance on small molecule self-assembled nano-drug delivery system / 药学学报

Since the application of biomedical nanotechnology in the field of drug delivery breathes new life into the research and development of high-end innovative agents, a substantial number of novel nano-drug delivery systems (nano-DDSs) have been successively developed and applied in the clinical practice. Among them, small molecule pure drug and prodrug-based nanoassemblies have grasped great attention, owing to the facile fabrication, ultrahigh drug loading and feasible industrial production. Herein, we provide an overview on the latest updates of small-molecule nanoassemblies. Firstly, the self-assembled prodrug-based nano-DDSs are introduced, including nanoassemblies formed by amphiphilic monomeric prodrugs, hydrophobic monomeric prodrugs and dimer monomeric prodrugs. Then, the recent advances on nanoassemblies of small molecule pure chemical drugs and biological drugs are presented. Furthermore, carrier-free small-molecule hybrid nanoassemblies of pure drugs and/or prodrugs are summarized and analyzed. Finally, the rational design, application prospects and clinical challenges of small-molecule self-assembled nano-DDSs are discussed and highlighted. This review aims to provide scientific reference for constructing the next generation of nanomedicines.

Study on mechanism of cryptotanshinone against non-small cell lung cancer based on network pharmacology / 中国药理学通报

Aim To explore the mechanism of cryptotanshinone (CTS) against non-small cell lung cancer (NSCLC) by using network pharmacology and bioinformatics methods. Methods Taking CTS as the research object, TCMSP database, SwissTargetPrediction and PharmMapper target prediction platform were used to collect CTS related targets; OMIM database, Gene-Cards data-base and TCGA database were employed to collect NSCLC related targets; String database and Cytoscape software were applied to construct PPI of intersection targets Network diagram, the hub targets were screened out, and AutoDock Vina was used for molecular docking verification; the R language clusterProfiler package was used to perform GO and KEGG enrichment analysis on the intersection targets; Cytoscape software was employed to construct the "CTS intersection targets-KEGG pathway" network. Results As a result, 75 intersecting targets were obtained, mainly involving various biological processes such as signal transduction, phosphorylation and dephosphorylation, apoptosis and vascular regulation, mainly through pancreatic cancer, colorectal cancer, cancer pathways and JAK-STAT signaling pathways. And cellular pathways such as apoptosis and natural killer cell-mediated cytotoxicity exerted their anti-NSCLC effects. Conclusions CTS exerts its anti-NSCLC effect through multiple targets and multiple pathways, which provides the theoretical support for further in-depth research.

Advance on inducing ferroptosis of tumor cells based on nanodelivery technology / 药学学报

At present, cancer is still one of the most serious threats to human health. Despite the wide application of multiple cancer therapies in clinical practice, the therapeutic effects of most cancers are still far from satisfactory. In recent years, the discovery of regulated cell death may be a good first step on the road to treat cancer. Ferroptosis is triggered by lipid peroxidation of unsaturated fatty acids in cell membrane catalyzed by iron ion. It has been widely concerned as an emerging target for cancer therapy. With the booming of biomedical nanotechnology, ferroptosis as an emerging therapeutic target has attracted extensive attention. Here, we review the advance on the intersection of ferroptosis and biomedical nanotechnology. First, the research background of ferroptosis and nano-preparation as well as the feasibility of ferroptosis-based nano-drug delivery systems (nano-DDS) for cancer treatment are presented and analyzed. Then, the strategies for inducing ferroptosis based on nano-DDS are summarized, mainly including: the promotion of Fenton reaction, the inhibition of glutathione peroxidase 4 (GPX-4) and the restriction of the cysteine-glutamate exchange transporter (system Xc-). Furthermore, the combination therapy strategies based on biomedical nanotechnology induced ferroptosis are also discussed. Finally, we shine the spotlight on the prospects and challenges of ferroptosis-based nanotherapeutics in clinical application.

Impact of mild hypothermia therapy on hemodynamics during the induction stage in neonates with moderate to severe hypoxic-ischemic encephalopathy / 中国当代儿科杂志

OBJECTIVE@#To study the changes in hemodynamics during the induction stage of systemic mild hypothermia therapy in neonates with moderate to severe hypoxic-ischemic encephalopathy (HIE).@*METHODS@#A total of 21 neonates with HIE who underwent systemic mild hypothermia therapy in the Department of Neonatology, Dongguan Children's Hospital Affiliated to Guangdong Medical University, from July 2017 to April 2020 were enrolled. The rectal temperature of the neonates was lowered to 34℃ after 1-2 hours of induction and maintained at this level for 72 hours using a hypothermia blanket. The impedance method was used for noninvasive hemodynamic monitoring, and the changes in heart rate (HR), mean arterial pressure (MAP), stroke volume (SV), cardiac output (CO), cardiac index (CI), and total peripheral resistance (TPR) from the start of hypothermia induction to the achievement of target rectal temperature (34℃). Blood lactic acid (LAC) and resistance index (RI) of the middle cerebral artery were recorded simultaneously.@*RESULTS@#The 21 neonates with HIE had a mean gestational age of (39.6±1.1) weeks, a mean birth weight of (3 439±517) g, and a mean 5-minute Apgar score of 6.8±2.0. From the start of hypothermia induction to the achievement of target rectal temperature (34℃), there were significant reductions in HR, CO, and CI (@*CONCLUSIONS@#The systemic mild hypothermia therapy may have a significant impact on hemodynamics in neonates with moderate to severe HIE, and continuous hemodynamic monitoring is required during the treatment.

Microsurgical subinguinal varicocelectomy with delivery of the testis and ligation of gubernacular veins: Evaluation of clinical effects / 中华男科学杂志

<p><b>Objective</b>To compare the clinical effects and postoperative complications of microsurgical subinguinal varicocelectomy (MSV) with or without delivery of the testis and ligation of gubernacular veins in the treatment of varicocele.</p><p><b>METHODS</b>We retrospectively analyzed the clinical data about 163 varicocele patients treated by MSV, 40 with (group A) and the other 123 without delivery of the testis and ligation of gubernacular veins (group B). We compared the operation time, postoperative complications, rate of recurrence, and semen parameters before and at 3 months after surgery between the two groups of patients.</p><p><b>RESULTS</b>The operation time was significantly longer in group A than in B (［81.1 ± 20.0］ vs ［62.3 ± 9.6］ min, P = 0.041). Sperm concentration, total sperm count per ejaculate, sperm viability, and the percentage of progressively motile sperm were significantly improved in both groups at 3 months after MSV as compared with the baseline (P < 0.05). There were no statistically significant differences in the above semen parameters between the two groups of patients with grade Ⅲ varicocele before and after surgery (P < 0.05). Scrotal edema developed in 5 cases in group A and wound infection in 2 cases in group B after MSV, but no postoperative testicular atrophy or recurrence was observed in either of the two groups.</p><p><b>CONCLUSIONS</b>MSV with delivery of the testis and ligation of gubernacular veins showed no advantages over that without in reducing varicocele recurrence and improving semen parameters, but rather involved longer operation time and a higher incidence rate of postoperative complications.</p>

Inhibitor of NADPH oxidase slow photoreceptor cell death in the retinal degeneration of rd mice / 中华实验眼科杂志

Background Our previous study demonstrated that microglial activation is closely associated with photoreceptor apoptosis in rd mice.Recent studies on central nervous system (CNS) showed that activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase plays a key role in the microglia activation and neural cell death.However,the mechanism of NADPH oxidase during the retinal degeneration and the effect of NADPH oxidase inhibitor on photoreceptor apoptosis are concerned.Objective The aim of this study was to further explore the production of reactive oxygen species (ROS) by NADPH oxidase in the retinal degenerative process of rd mice and protection of NADPH oxidase inhibitor on photoreceptors.Methods Sixty rd mice at postnatal day 9 (P9) were randomized into the experimental group and the control group by throwing coins method.Apocynin,a NADPH oxidase inhibitor,was intraperitoneally injected in the dose of 10 mg/kg (0.01 ml/kg) once daily for 5 days (P13) in the experimental group,and the equal amount of PBS was used in the same way in the control group,and 10 C57BL/6N mice without injection of any drugs served as the wild type mice group.All the mice were sacrificed in P14 for the preparation of retinal sections.The expression of ROS in the retina was detected by dihydroethidium (DHE) fluorescence staining.Expression level of rhodopsin mRNA in the photoreceptor of the mice was determined by real-time PCR,and the thickness of retinal outer nuclear layer (ONL) in the mice of the experimental group and the control group was measured using hematoxylin & eosin staining.The use and care of the animals complied with the Statement of Association for Research in Vision and Ophthalmology.Results DHE staining showed that the ROS presented with the red fluorescence in the mouse retinas.In the rd mice of the experimental group,the ROS fluorescence intensity was dramatically enhanced in comparison with C57BL/6N mice,but weakened in comparison with the rd mice of the control group.Real-time PCR revealed that the relative expressing level of rhodopsin mRNA in the photoreceptor was (4.21±0.33) in the experimental group and (0.93±0.24) in the control group,showing a significant difference between them (t =2.360,P =0.000).The thickness value of retinal ONL was (35.95±1.63)μm in the mice of the experimental group,which was significantly higher than that in the mice of the control group ([23.17±1.38] μm) (t=3.850,P=0.016).Conclusions In the retinal degeneration of rd mice,activation of NADPH oxidase increases the ROS production.Apocynin can slow the apoptosis procedure of photoreceptor cells of rd mice.

Clinical application of extracorporeal membrane oxygenation for treatment of adult refractory cardiogenic shock / 中华心血管病杂志

<p><b>OBJECTIVE</b>To summarize the clinical experience of extracorporeal membrane oxygenation (ECMO) treatment for adult refractory cardiogenic shock.</p><p><b>METHODS</b>From January 2003 to January 2011, patients with refractory cardiogenic shock required veno-arterial ECMO by failure of conventional therapy and intra-aortic balloon pump counterpulsation therapy were retrospectively studied. Patients with severe traumatic brain injury, advanced malignancies and multiple organ failure were excluded. Patients were divided into weaned group (n = 31) and not weaned group (n = 23) according to the ECMO weaning.</p><p><b>RESULTS</b>The duration of ECMO was 24.16 (14.12, 56.75) hours. Twenty-two out of 31 patients in the weaned group survived and were discharged, 9 patients died after successfully weaned from ECMO (5 due to multisystem organ failure, 2 due to reoccurred cardiogenic shock, 1 due to infectious shock and 1 due to disseminated or diffuse intravascular coagulation). Pre-ECMO mean arterial pressure, ejection fraction, the duration of ECMO were significantly higher while pre-ECMO blood lactate [(8.64 ± 3.17) vs. (14.44 ± 2.52) , P < 0.01], the duration of ROSC [ (16.70 ± 5.29) vs. (35.64 ± 5.89), P < 0.01] and multisystem organ failure [0 vs. 17.4% (4/23) , P < 0.05] were lower in weaned group than in not wean group.</p><p><b>CONCLUSIONS</b>ECMO is an effective mechanical assistant therapy strategy for adult refractory cardiogenic shock patients. Timely applying this strategy on suitable patients is crucial for the success of ECMO. Cardiac function and reversibility of heart failure are key factors determine the fate of weaned or not weaned ECMO in adult refractory cardiogenic shock patients.</p>

Current status of hepatitis B immunization and strengthened immune memory among first-year middle school students in Tianjin / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the immunization status of hepatitis B vaccine who were inoculated at birth, HBV infections and the vaccine booster effect in the first-year middle school students (12 - 14 years old).</p><p><b>METHODS</b>A cluster, stratified simplified random sampling method was administrated. The sample size was at least 218, which was calculated by Epi Info 3.3.2 software at 53% the minimum acceptable anti-HBs positive rate and 95% confidence level. A total of 250 and 236 students participated in the infection status and booster immunization effects investigation. The HBsAg, anti-HBs and anti-HBc IgG were detected by Enzyme-linked immunosorbent assay (ELISA). HBV DNA was detected by fluorescence quantitative PCR, and the diagnostic test kit were produced respectively by ABBOTT, Diasorin and Beijing Wantai Biological Pharmacy Enterprise Co.</p><p><b>RESULTS</b>For the immunization status before booster: the positive rate of anti-HBs was 62.80% (157/250), the GMT was 73.79 IU/L; the currently HBV infection rate (HBsAg and anti-HBc positive) was 2.80% (7/250). After injection, the anti-HBs positive rate was 94.92% (224/236). Compared with the before booster results, the significant difference was observed (χ(2) = 73.92, P = 0.00). The GMT was 521.15 IU/L, comparing with the before booster results, there was significant difference (t = 15.98, P = 0.00). The anti-HBs conversion rate (from negative to positive) was 91.86% (79/86) after immune-enhancement; of which, 11 students got the second dose of booster vaccine who are no-responders after first injection, in addition 8 students got the anti-HBs.</p><p><b>CONCLUSION</b>It is an effective method to put the first-year middle school students into the immune-enhancement program, so as to improve the immunization memory effect and avoid the loss of protective antibodies.</p>

Study on the report criteria and focus management mode of the virus hepatitis cases in Tianjin / 中华预防医学杂志

<p><b>OBJECTIVE</b>To establish the focus management mode and the report criteria more perfectly for the virus hepatitis cases, especially for the hepatitis B.</p><p><b>METHODS</b>One district was set as the research area, in which there was enough cases resource and relatively separated from the other districts, then a first or second-class hospital was appointed to take the cases focus diagnosis, report and management.</p><p><b>RESULTS</b>The focus hospitals had reported 97% (323/331) of cases in the research area between June,2007 and June,2008; moreover,the rate in establishing case-card was 97.21% (314/323), as compared with that in period of 2007 (261), the cases reported declined 61.30% in the first half year of 2008 (101).</p><p><b>CONCLUSION</b>It should be an imperative situation to establish a report criteria and management mode for virus hepatitis (hepatitis B), however it is necessary to have more supports from health administrations.</p>

Assessment time on mental disability due to brain damage / 法医学杂志

OBJECTIVE@#To determine the best time for assessing mental disability due to brain damage.@*METHODS@#Ninety-three mental disabilities due to brain damage in traffic accidents were assessed and their follow-up studies were taken in different period after the brain injury: 3 months, 6 months, 9 months and 12 months. The patients' brain imaging, electroencephalogram (EEG) and detailed medical history were collected. Then to interview the patients' family members and to assess the patients' mental conditions with Wechsler Adult Intelligence Scale (WAIS), Social Disability Screening Schedule (SDSS), and Activity of Daily Living Scale (ADL). Diagnosis and disability assessments were based on all of the above information.@*RESULTS@#ADL and SDSS had good distinction between different levels of disability and different time. The overall sample demonstrated that there was no statistically significant difference between patients' ADL and SDSS averages in 9 and 12 months. For mild disability, there was no statistically significant difference between ADL and SDSS averages in 6, 9 and 12 months. For moderate disability, there was no statistically significant difference between ADL and SDSS in 9 and 12 months. And there was no statistically significant difference between ADL and SDSS averages in 6, 9 and 12 months for severe disability.@*CONCLUSION@#For mild disability, it is recommended to assess the mental disability 6 months after the injury, for moderate disability, it is 9 months. The statistics data recommended that the best assessment time for severe disability is 6 months after injury. However, our comprehensive analysis concludes that the suitable time is 9 months after injury.

Effect of heat stress on expression of gp96 in K562 cell line of the chronic myeloid leukemia and its significance / 中国实验血液学杂志

This study was purposed to investigate the effect of different heat stress conditions on expression level of heat shock protein gp96 in K562 cell line of chronic myeloid leukemia in order to provide experiment basis for seeking optimal heat stress condition increasing extraction amount of gp96 from K562 cells. The expression changes of gp96 in K562 cell line was detected by immunocytochemistry under 38, 40, 42, 44, 46 and 48 degrees C for 30 minutes in water, by flow cytometry under 40, 44, 48 and 52 degrees C for 30 minutes in water, by Western blot under 40, 44, 48 and 52 degrees C for 30 minutes in water. Immunocytochemistry assay showed that gp96 existed mainly in cytoplasm. The peak of gp96 expression was at 30 minutes after 48 degrees C in water. The result of flow cytometry was consistent to immunocytochemistry detection results under temperatures 40, 44, 48 and 52 degrees C (P < 0.01). Western blot showed that detection result was the same as the immunocytochemistry and flow cytometry detections. In conclusion, the expression of gp96 in K562 cell line reached peak at 30 minutes after 48 degrees C in water. This condition may be an effective preparative condition for extraction of gp96 from K562 cells.

Synchronous primary carcinomas of the bladder and prostate / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To determine the incidence of adenocarcinoma of the prostate for patients undergoing radical cystoprostatectomy for bladder cancer in Taiwan.</p><p><b>METHODS</b>A total of 248 patients in Taiwan who were histologically confirmed for transitional cell carcinoma of the bladder underwent cystoprostatectomy. Histopathologic evaluation of the prostate specimens sectioned at 5 mm intervals was performed.</p><p><b>RESULTS</b>Of the 248 patients, 10 (4.03%) were found to have prostate cancer. Of the 10 cases of unsuspected prostate cancer, eight proved to be at stage T1 or T2, and two at T3 and T4, respectively. This rate of incidentally found prostate cancer amongst our bladder cancer patients appeared to be lower than that found in bladder cancer patients in similar studies in USA.</p><p><b>CONCLUSION</b>Although the incidence of incidental prostate cancer in patients in Taiwan with bladder cancer is not high compared with that in Western countries, we suggest that digital rectal examination and prostate-specific antigen (PSA) are important screening tools for men with bladder cancer, especially for those aged 60 years and older in Taiwan.</p>

The heat shock protein 70 antisense oligomers enhance the sensitivity of bladder cancer cell EJ to mitomycin C / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate whether the heat shock protein (HSP) 70 antisense oligomers can enhance the sensitivity of bladder cancer cell EJ to mitomycin C.</p><p><b>METHODS</b>The HSP70 mRNA of EJ cells was blocked by the 10 micromol/L HSP70 antisense oligomers, while its effect on cell growth was evaluated by methyl thiazolyl tetrazolium (MTT) and colony forming ability test.</p><p><b>RESULTS</b>The HSP70 expressions in HSP70 antisense treated group were lower than the corresponding sense and nonsense treated groups (P < 0.01). While, the increased sensitivity of EJ to mitomycin C was found in antisense treated group, compared with the corresponding sense and nonsense treated groups (P < 0.01).</p><p><b>CONCLUSION</b>The sensitivity of bladder cancer cell EJ to mitomycin C was enhanced by the blockage of the HSP70 expression.</p>

Reconstruction of sensory function of thumb and forefinger pulp by the lateral island flap with neurovascular pedicle of finger / 中国康复理论与实践

@#ObjectiveTo explore the effect of the lateral island flap with neurovascular pedicle of finger on reconstruction of the sensory function of thumb and forefinger pulp.MethodsSensory functions of 9 thumb pulps and 7 forefinger pulps were reconstructed by the lateral island flap with neurovascular pedicle of ring finger and middle finger.ResultsAll 16 island flaps were survived. Follow-up survey was 6 months to 2 years. The appearance and texture of flaps were satisfactory with sensory function being S3-S3+ grade.ConclusionThe lateral island flap with neurovascular pedicle of ring finger and middle finger is a good and reliable method to reconstruct the sensory function of thumb and forefinger pulp.

Differentiation and function of human dendritic cells influenced by heat shock protein gp96 purified from K562 cells / 中国实验血液学杂志

This study was to establish the method of purifying heat shock protein GP96 from K562 cells and explore the differentiation and function of human DC influenced by heat shock prolein (HSP). Using ammonium sulfate precipitation, conA-sepharose affinity chromatography and DEAE-sephacel anion exchange chromatography GP96 from K562 cells lysate was isolated and purified. The identification of the purified protein was controlled by Western blot with anti-human GP96 IgG. Human dendritic cell derived from peripheral blood mononuclear cell were cultured with purified GP96. The phenotype changes of DC were analyzed by flow cytometry and MLR was detected by MTT. The results showed that 60-80 microg GP96 was purified successfully from 1 x 10(10) K562 cells. DC stimulated with HSP-GP96 had higher expression rates of CD83, CD86, HLA-DR and lower expression rates of CD1a and had stronger ability to induce T cells proliferation. It is concluded that heat shock protein GP96 can be isolated and purified from K562 cells and could induce maturation of dendritic cell. HSP-DC vaccine show stronger ability to induce T cell proliferation than DC.

Effect of transforming growth factor-beta1 on proliferation and apoptosis of mononuclear cells of cord blood / 中国实验血液学杂志

To explore the mechanism of transforming growth factor-beta1 (TGF-beta1) effect on umbilical cord blood mononuclear cells proliferation and apoptosis, 5-bromo-2'-deoxyurine (BrdU) incorporation assay was adopted to detect effect of TGF-beta1 on synthesis of DNA in cells. Western blot method was used to examine effect of TGF-beta1 on expression of cyclin A, Cyclin D1, CDK2 and CDK4 in G1 phase of cell cycle. Giemsa staining and flow cytometry (FCM) were performed to detected effect of TGF-beta1 on cell apoptosis. The results showed that (1) after culture of cells with IMDM containing 10% FBS, 10% FBS + 1 ng/ml TGF-beta1, 10% FBS + 2 ng/ml TGF-beta1 or 10% FBS + 5 ng/ml TGF-beta1 for 12 hours the OD values of TGF-beta1 group were significantly lower than control group (P <0.01); after culture for 24 hours the OD values of 1 ng/ml TGF-beta1 group had no significant difference compared with control group (P >0.05), but the OD values of 2 ng/ml and 5 ng/ml TGF-beta1 groups were significantly lower than control group (P <0.05). (2) 2 ng/ml TGF-beta1 could significantly inhibit the production of cyclin A, cyclin D1, CDK2 and CDK4, the protein levels were significantly lower than control group. (3) when the cells were co-cultured with 2 ng/ml TGF-beta1 for 12 and 24 hours, Giemsa staining and FCM detection could display typical apoptosis, the apoptosis rates were 14.42% and 31.98%, while apoptosis rate in control were 4.71% and 5.76%. It is concluded that TGF-beta1 can inhibit production of G1 cyclins and CDKs of umbilical cord blood mononuclear cells, arrest cells in the G1 phase of cell cycle and induce cell apoptosis. Thus, TGF-beta1 may be an important negative modulator in hematopoiesis.

A quantitative assay for telomerase activity in peripheral blood mononuclear cells from patients with acute leukemia / 中国实验血液学杂志

To establish a quantitative assay for telomerase activity and analyze the telomerase activity in peripheral blood mononuclear cells (PBMNC) from patients with acute leukemia, a fluorescent dye, PicoGreen, was added to the products after telomere repeat amplification protocol. The samples were excited at 480 nm and the fluorescence emission intensity was measured at 520 nm using a spectrofluorometer. Telomerase activity was detected in PBMNCs from 20 cases of normal individuals and 25 patients with acute leukemia. The results showed that the fluorescence of PicoGreen binding to double-stranded DNA specifically was enhanced with increase of DNA quantities. In conclusion, the met hod is rapid, simple and quantitative, the telomerase activities of PBMNCs from acute leukemia patients are significantly higher than that of the normal controls.

Dendritic cells cultured with human umbilical cord serum instead of fetal calf serum / 中国实验血液学杂志

To investigate whether the dendritic cells (DC) could grow up in cultural system with umbilical cord serum (UCS), the UCS was used in the culture instead of fetal calf serum. The phenotype of dendritic cells was detected by flow cytometry and the antigen presenting ability of DC in allo-MLR was measured by MTT assay. The results showed that DC grown in UCS (UCS-DC) had higher expression rate of CD86, CD83 and HLA-DR than that in grown in FCS (FCS-DC). (P < 0.05), and their expression of CD1a was lower than that of FCS-DC. The ability to induce T cell proliferation had no difference between UCS-DC and FCS-DC. It is suggested that dendritic cells with more mature phenotype had been produced in the medium containing UCS than those in the medium containing FCS, and UCS-DC possessed potent ability to stimulate proliferation of allogeneic T cells.

p21(WAF1) transfection decreases sensitivity of K562 cells to VP-16 / 中国实验血液学杂志

The objective of this study was to explore the effect of p21(WAF1) on the sensitivity to chemotherapeutic agent VP-16, etoposide, in leukemia cell line K562. A p21(WAF1) retroviral expression vector was constructed, and mediated by FuGENE(TM)6, it was transfected into K562 cells, which without p21(WAF1) expression. The ecotropic expression of p21(WAF1) in K562 cells was identified by RT-PCR and Western blot, and named K562-p21(WAF1) cell. The K562-p21(WAF1) cells were exposed to VP-16 at different concentrations and different times, then, the sensitivity to VP-16 was examined by cell viability and MTT assay, the apoptosis induced by VP-16 was examined by DNA fragments electrophoresis and flow cytometric Annexin V-PI dual labeling technique. The results showed that the ecotropic expression of p21(WAF1) decreased the sensitivity of K562 cells to VP-16. After treatment of VP-16, the DNA ladder was examined in control K562-neo cells at 20 microgram/ml, but in K562-p21(WAF1) cells at 80 microgram/ml. With FCM, the number of apoptotic K562-neo cells was 14.9% and 25.4% respectively after treated with 20 microgram/ml VP-16 for 12 and 24 hours, and it was 6.94% and 10.96% in K562-p21(WAF1) cells. Our results suggest that the expression of p21(WAF1) could reduce the sensitivity of K562 cells to VP-16 and inhibit the apoptosis of K562 cells

Transfer and Expression of Recombinant Human Thrombopoietin Gene in COS-7 Cells and Mice In Vivo / 中国实验血液学杂志

In order to investigate the expression of recombinant TPO gene in COS-7 cells and in vivo of the mouse model, eukaryotic expressing plasmid pcd2/TPO with human TPO cDNA was constructed with DNA recombinant techniques. The plasmid pcd2/TPO was transiently transfected into the COS-7 cells by means of lipofection, the naked pcd2/TPO plasmid was injected into the skeletal muscle of mice with electric pulses. RT-PCR and ELISA methods were used to detect the TPO expression of the transfected COS-7 cells, both showed high level expression. The MTT test showed the expressed TPO had proliferative activity to TPO-dependent cell line. High efficiency of gene transfer in transgenic mice was also observed by RT-PCR and immunohistochemical methods. The serum TPO level [(1 185 +/- 264) ng/L] in transgenic mice was quite different compared with the normal mice [(250 +/- 76) ng/L]. All these results provided solid foundations for the research of TPO gene therapy in the future.