Baseline serum uric acid level is associated with progression-free survival, disease control rate, and safety in postoperative patients with colorectal cancer treated by FOLFOX, FOLFIRI, or XELOX.

Background: High serum uric acid (SUA) levels increase the risk of overall cancer morbidity and mortality, particularly for digestive malignancies. Nevertheless, the correlation between SUA level and clinical outcomes of the postoperative patients with colorectal cancer (CRC) treated by chemotherapy is unclear. This study aimed at exploring the relationship between baseline SUA level and progression-free survival (PFS), disease control rate (DCR), and safety in postoperative CRC patients receiving chemotherapy. Patients and Methods: We conducted a retrospective study to evaluate the relationship between baseline SUA level and PFS, DCR, and incidence of serious adverse events of 736 postoperative CRC patients treated with FOLFOX, FOLFIRI or XELOX at our center. Results: Data from our center suggested that high baseline SUA level is linked to poor PFS in non-metastatic CRC patients using FOLFOX (HR=2.59, 95%CI: 1.29-11.31, p=0.018) and in male patients using FOLFIRI (HR=3.77, 95%CI: 1.57-39.49, p=0.012). In patients treated by FOLFIRI, a high SUA is also linked to a low DCR (p=0.035). In patients using FOLFOX, high baseline SUA level is also linked to a high incidence of neutropenia (p=0.0037). For patients using XELOX, there is no significant correlation between SUA level and PFS, effectiveness, or safety. Conclusions: These findings imply that a high SUA level is a promising biomarker associated with poor PFS, DCR and safety of postoperative CRC patients when treated with FOLFOX or FOLFIRI.

Celastrol mitigates inflammation in sepsis by inhibiting the PKM2-dependent Warburg effect.

BACKGROUND: Sepsis involves life-threatening organ dysfunction and is caused by a dysregulated host response to infection. No specific therapies against sepsis have been reported. Celastrol (Cel) is a natural anti-inflammatory compound that shows potential against systemic inflammatory diseases. This study aimed to investigate the pharmacological activity and molecular mechanism of Cel in models of endotoxemia and sepsis. METHODS: We evaluated the anti-inflammatory efficacy of Cel against endotoxemia and sepsis in mice and macrophage cultures treated with lipopolysaccharide (LPS). We screened for potential protein targets of Cel using activity-based protein profiling (ABPP). Potential targets were validated using biophysical methods such as cellular thermal shift assays (CETSA) and surface plasmon resonance (SPR). Residues involved in Cel binding to target proteins were identified through point mutagenesis, and the functional effects of such binding were explored through gene knockdown. RESULTS: Cel protected mice from lethal endotoxemia and improved their survival with sepsis, and it significantly decreased the levels of pro-inflammatory cytokines in mice and macrophages treated with LPS (P < 0.05). Cel bound to Cys424 of pyruvate kinase M2 (PKM2), inhibiting the enzyme and thereby suppressing aerobic glycolysis (Warburg effect). Cel also bound to Cys106 in high mobility group box 1 (HMGB1) protein, reducing the secretion of inflammatory cytokine interleukin (IL)-1ß. Cel bound to the Cys residues in lactate dehydrogenase A (LDHA). CONCLUSION: Cel inhibits inflammation and the Warburg effect in sepsis via targeting PKM2 and HMGB1 protein.

Reverse Transcription Recombinase-Aided Amplification Assay With Lateral Flow Dipstick Assay for Rapid Detection of 2019 Novel Coronavirus.

Background: The emerging Coronavirus Disease-2019 (COVID-19) has challenged the public health globally. With the increasing requirement of detection for SARS-CoV-2 outside of the laboratory setting, a rapid and precise Point of Care Test (POCT) is urgently needed. Methods: Targeting the nucleocapsid (N) gene of SARS-CoV-2, specific primers, and probes for reverse transcription recombinase-aided amplification coupled with lateral flow dipstick (RT-RAA/LFD) platform were designed. For specificity evaluation, it was tested with human coronaviruses, human influenza A virus, influenza B viruses, respiratory syncytial virus, and hepatitis B virus, respectively. For sensitivity assay, it was estimated by templates of recombinant plasmid and pseudovirus of SARS-CoV-2 RNA. For clinical assessment, 100 clinical samples (13 positive and 87 negatives for SARS-CoV-2) were tested via quantitative reverse transcription PCR (RT-qPCR) and RT-RAA/LFD, respectively. Results: The limit of detection was 1 copies/µl in RT-RAA/LFD assay, which could be conducted within 30 min at 39°C, without any cross-reaction with other human coronaviruses and clinical respiratory pathogens. Compared with RT-qPCR, the established POCT assay offered 100% specificity and 100% sensitivity in the detection of clinical samples. Conclusion: This work provides a convenient POCT tool for rapid screening, diagnosis, and monitoring of suspected patients in SARS-CoV-2 endemic areas.

[Analysis and Prevention of Gene Mutation Types of Severe Thala- ssemia in Hakka People in Gannan of Jiangxi Province].

OBJECTIVE: To investigate the types and proportion of gene mutations of thalassemia in Hakka people in Gannan Area of Jiangxi, and to provide some references for prevention and treatment of thalassemia major, genetic counseling and epidemiological studies. METHODS: 81 cases Hakka patients with severe thalassemia admitted treated in First Affiliated Hospital of Gannan Medical College from January 2009 to June 2019 were enrolled. The deletion type of α-thalassemia was detected by Gap-PCR. The point mutations of α-thalassemia and ß-thalassemia were detected by PCR-RDB. The thalassemia gene was detected and analyzed in the patients with anemia, and the frequency of gene mutation was calculated. RESULTS: Among 81 Hakka patients with thalassemia major, 4 ß-thalassemia (homozygote) genotypes were detected out, including: CD41-42（TTCT）(19 cases), ß-IVS-II-654 (C→T) (9 cases), -28M (A→G) (1 case), CD17 (A→T) (1 case); 12 ß-thalassemithalassemia (heterozygote) genotypes were detected out, including: CD41-42(-TTCT)/ß-IVS-II-654(C→T) (15 cases, 29.41%), ß-IVS-II-654(C→T)/ß-28M(A→G) (13 cases，25.49%) ； CD41-42(-TTCT)/ß-28M(A→G) (9 cases，17.65%); ß-IVS-II-654(C→T) /CD27/28(+C) (3 cases， 5.88%) ； CD41-42(-TTCT)/CD27/28(+C)(3 case，5.88%)；ß-28M(A→G)/CD17(A→T) (2 cases，3.92%)；CD41-42(-TTCT)/CD17(A→T), CD41-42(-TTCT)/Βe, ß-IVS-II-654(C→T)/ß-29、ßCD17（A→T）/CD71-72(+a), ßCD71-72/ß-28M(A→G), ß-28M(A→G) /ß-IVS-II-654(C→T)(1 cases，1.96%). There were 3 cases of ß homozygous thalassemia with α-thalassemia gene and 5 cases of ß heterozygotes thalassemia with α-thalassemia gene. CONCLUSION: The incidence rate of thalassemia in Hakka people in Gannan Area of Jiangxi is relatively high. The distribution of gene mutation types is as follows: the genotype of CD41-42 (-TTCT) is the main genotype of ß-thalassemia (homozygous); the major genotypes of ß- thalassemia (heterozygotes) are CD41-42 (-TTCT)/ß-IVS-II-654 (C→T) and ß-IVS-II-654 (C→T) /ß-28M (A→G); CD41-42 (-TTCT) gene is dominant in ß-complex α-thalassemia.

Establishment and Evaluation of a Novel Method Based on Loop-Mediated Isothermal Amplification for the Rapid Diagnosis of Thalassemia Genes.

PURPOSE: Currently, thalassemia is commonly detected using gap-polymerase chain reaction (PCR) and deoxyribonucleic acid (DNA) reverse dot blot, which have high requirements of space, instruments, and personnel. Therefore, it is necessary to develop a new method for thalassemia detection with high sensitivity, low cost, and simple and fast operation. In this study, we aimed to design and evaluate a new method for detecting three α-thalassemia genes including -Southeast Asian (SEA), -α3.7, and -α4.2 and five ß-thalassemia genes including 654M, 41/42M, -28M, 17M, and 27/28M based on loop-mediated isothermal amplification (LAMP). METHODS: Primer sequences were designed using Primer Explorer V4 software. Blood samples (5 mL) were collected from all participants in EDTA. DNA was extracted using Chelex 100 and was subjected to LAMP. LAMP products were detected by fluorescence development in ultraviolet light. RESULTS: We found that LAMP assays for positive samples of thalassemia reached a plateau before 60 minutes, whereas the negative control samples entered the plateau after 70 minutes or showed no amplification. The concentration range of positive reactions was between 20-60 pg/µL and 20-60 ng/µL. Additionally, there were no cross-reactivities among 8 thalassemia subtypes. For clinical samples, the positive sample tube showed strong green fluorescence, whereas the negative tube showed light green fluorescence. According to these results, the LAMP method has high sensitivity for detecting thalassemia (252/254). However, 43 false-positive results were obtained in the LAMP test. The LAMP assay was also of low cost and with simple and fast operation. CONCLUSION: The novel LAMP assay can be completed within 60 min using a heating block or a water bath, and the result can be read visually based on color change to detect thalassemia. The LAMP assay fulfills the requirements of field application and resource-limited areas, especially those with primary hospitals and rural areas.

Design and Evaluation of a Novel Multiplex Real-Time PCR Melting Curve Assay for the Simultaneous Detection of Nine Sexually Transmitted Disease Pathogens in Genitourinary Secretions.

Background: Sexually transmitted diseases (STD) are a major cause of infertility, long-term disability, ectopic pregnancy, and premature birth. Therefore, the development of fast and low-cost laboratory STD diagnostic screening methods will contribute to reducing STD-induced reproductive tract damage and improve women's health worldwide. In this study, we evaluated a novel multiplex real-time PCR melting curve assay method for the simultaneous detection of 9 STD pathogens, including Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, Mycoplasma hominis, Ureaplasma urealyticum, Ureaplasma parvum, and herpes simplex virus. Methods: The analytical performance of the method, including its limit of detection (LOD), specificity, repeatability, and effect on different DNA extraction kits were evaluated. Additionally, we obtained 1,328 clinical specimens from 3 hospitals to detect the 9 STD pathogens using multiplex real-time PCR melting curve and Sanger sequencing, to evaluate the sensitivity, specificity, and consistency of the assay method. Results: The results showed that the analytical sensitivity of the novel multiplex real-time PCR melting curve assay is very excellent, with LOD of DNA corresponding to <200 copies/µL for the DNA of the 9 STDs and 1.00 × 104 color change unit /ml for those of UU and UP. Additionally, this assay demonstrated excellent analytical specificity, excellent repeatability, and its results had no effect of different DNA extraction kits. The performance, in terms of sensitivity (91.06-100%) and specificity (99.14-100%), was remarkable, since the consistency between it and Sanger sequencing was more than 0.85 in the clinic. Conclusion: The novel multiplex real-time PCR melting curve assay method has high sensitivity and specificity, relatively low cost, and simple to use for the simultaneous detection of 9 STD pathogens in genitourinary secretions.

Treatment of Periodontal Bone Defects with Stem Cells from Inflammatory Dental Pulp Tissues in Miniature Swine.

Background: Containing a certain proportion of mesenchymal stem cells, inflammatory dental tissue showed great tissue regeneration potential in recent years. However, whether it is applicable to promote tissue regeneration in vivo remains to be elucidated. Therefore, we evaluated the feasibility of stem cells from inflammatory dental pulp tissues (DPSCs-IPs) to reconstruct periodontal defects in miniature pigs. Methods: The autologous pig DPSCs-IPs were first cultured, appraised and loaded onto ß-tricalcium phosphate (ß-TCP). The compounds were then engrafted into an artificially-created periodontal defect. Three months later, the extent of periodontal regeneration was evaluated. Clinical examination, radiological examination and immunohistochemical staining were used to assess periodontal regeneration. Results: The data collectively showed that DPSCs-IPs from miniature pigs expressed moderate to high levels of STRO-1 and CD146 as well as low levels of CD34 and CD45. DPSCs-IPs have osteogentic, adipogenic and chondrogenic differentiation abilities. DPSCs-IPs were engrafted onto ß-TCP and regenerated bone to repair periodontal defects by 3 months' post-surgical reconstruction. Conclusion: Autologous DPSCs-IPs may be a feasible means of periodontal regeneration in miniature pigs.

Loss of Wnt4 expression inhibits the odontogenic potential of dental pulp stem cells through JNK signaling in pulpitis.

Dental pulp stem cell (DPSC)-based odontogenic regeneration in inflammatory conditions is important in the process of pulpitis. DPSCs have been reported to lose potential for odontogenic regeneration in inflammatory conditions. This study aims to determine the mechanism of impaired odontogenic differentiation of DPSCs in an inflammatory microenvironment. We regulated Wnt4 expression using recombinant lentiviral Wnt4 and Wnt4 siRNA. Alkaline phosphatase (ALP) and Alizarin red S (ARS) staining as well as Real-Time PCR were performed to evaluate the osteogenic differentiation potential of DPSCs with either upregulated or downregulated Wnt4. Furthermore, SP600125 was used to inhibit the potential downstream factor JNK1, and the osteogenic differentiation ability of DPSCs was evaluated. As shown, Wnt4 was downregulated in DPSCs under inflammatory conditions. Inhibition of Wnt4 expression in DPSCs negatively regulated odontogenic differentiation. Overexpression of Wnt4 in LPS-treated DPSCs promoted odontogenic differentiation. In addition, JNK1 was responsible for Wnt4-mediated odontogenic differentiation of DPSCs. Taken together, Wnt4 may function by affecting JNK signaling pathways in the process of impaired odontogenic regeneration by DPSCs under inflammatory conditions.

Prevalence of human papillomavirus infection among 71,435 women in Jiangxi Province, China.

Cervical cancer is the third most common cancer in women worldwide. Human papillomavirus (HPV) has been identified as an etiological factor for cervical cancer. Data on the prevalence and subtype distribution of HPV infection in Jiangxi Province are incomplete. In this study, we investigated HPV subtype distribution and prevalence in Jiangxi Province between August 1, 2010, and December 31, 2015. A total of 71,435 individuals ranging in age from 16 to 77 years were recruited. Cervicovaginal swabs were collected from each participant, and HPV screening was performed. Our results showed that the HPV prevalence was 22.49% in Jiangxi Province. Overall, 14.99% of individuals were positive for a single HPV type, and 7.49% were positive for multiple types. The most frequently detected low-risk genotypes were HPV-6, and high-risk genotypes were HPV-16, -18, -33, -52, and -58. The prevalence and type distribution of HPV infection exhibits regional and age differences; Yingtan had the highest incidence for high-risk HPV infection (32.00%), and peaks in the frequencies of HPV infections were seen for patients under 20 and over 60 years of age. In conclusion, we present data showing that the HPV prevalence varies significantly with age and regions in Jiangxi Province. These results can serve as valuable reference to guide Jiangxi cervical cancer screening and HPV vaccination programs.

Molecular epidemiological investigation of G6PD deficiency by a gene chip among Chinese Hakka of southern Jiangxi province.

In southern China, glucose-6-phosphate dehydrogenase (G6PD) deficiency is a significant health problem, and the incidence ranged from 0.5 to 4.08% in different Chinese population. The aims of this study are to investigate the molecular epidemiological characteristic of the G6PD gene among Chinese Hakka in southern Jiangxi province. 2331 unrelated subjects were screened for G6PD deficiency by a fluorescent test. DNA from deficient individuals was analyzed by a gene chip analysis for thirteen common Chinese G6PD mutations. In total, 3.60% (82/2331; 95% CI 2.77-4.27) of the sample were found to be G6PD-deficient. Eight mutations were found from 80 samples. However, mutation(s) for the two remaining samples were unknown. The most common mutations were G6PD Canton (1376 G>T) and G6PD Kaiping (1388 G>A), and the following mutations were 1311 polymorphism (1311 C>T), G6PD Gaohe (95 A>G), G6PD Chinese-5 (1024 C>T), G6PD Maewo (1360 C>T), Shunde (592 C>T), G6PD Viangchan (871 G>A) and Chinese-3 (493 A>G). This is the first report of G6PD deficiency among Chinese Hakka population in Jiangxi province.

High resolution melting analysis: a rapid screening and typing tool for common ß-thalassemia mutation in Chinese population.

ß-thalassemia is a common inherited disorder worldwide including southern China, and at least 45 distinct ß-thalassemia mutations have been identified in China. High-resolution melting (HRM) assay was recently introduced as a rapid, inexpensive and effective method for genotyping. However, there was no systemic study on the diagnostic capability of HRM to identify ß-thalassemia. Here, we used an improved HRM method to screen and type 12 common ß-thalassemia mutations in Chinese, and the rapidity and reliability of this method was investigated. The whole PCR and HRM procedure could be completed in 40 min. The heterozygous mutations and 4 kinds of homozygous mutations could be readily differentiated from the melting curve except c.-78A>G heterozygote and c.-79A>G heterozygote. The diagnostic reliability of this HRM assay was evaluated on 756 pre-typed genomic DNA samples and 50 cases of blood spots on filter paper, which were collected from seven high prevalent provinces in southern China. If c.-78A>G heterozygote and c.-79A>G heterozygote were classified into the same group (c.-78&79 A>G heterozygote), the HRM method was in complete concordance with the reference method (reverse dot blot/DNA-sequencing). In a conclusion, the HRM method appears to be an accurate and sensitive method for the rapid screening and identification of ß-thalassemia mutations. In the future, we suggest this technology to be used in neonatal blood spot screening program. It could enlarge the coverage of ß-thalassemia screening program in China. At the same time, its value should be confirmed in prospectively clinical and epidemiological studies.

Molecular epidemiological characterization and health burden of thalassemia in Jiangxi Province, P. R. China.

BACKGROUND: Thalassemia is the most common inherited disease in southern China. However, this disorder is usually ignored by Jiangxi provincial health system and government due to lack of epidemiological data. MATERIALS AND METHODS: A total of 9489 samples from Hakka Han and Gan-speaking Han in three geographical areas of Jiangxi Province were analyzed for both complete blood cell (CBC) count and reverse dot blot (RDB) gene chip for thalassemia. RESULTS: 1182 cases of suspected thalassemia carriers with microcytosis (MCV<82 fL) were found by CBC count, and were tested by RDB gene chip to reveal a total of 594 mutant chromosomes, including 433 α-thalassemia mutant chromosomes and 172 ß-thalassemia mutant chromosomes. Our results indicated a higher prevalence of thalassemia with the heterozygote frequency of 9.49% in southern Jiangxi province, whereas the low frequency was found in middle (3.90%) and northern Jiangxi (2.63%). CONCLUSIONS: Based on the epidemiological data, the estimated numbers of pregnancies in Jiangxi province in which the fetus is at risk for ß-thalassemia major or intermedia, Bart's hydrops fetalis and Hb H disease are 34 (95% CI, 16 to 58), 79 (95% CI, 50 to 114) and 39 (95% CI, 27 to 58) per year, respectively. We suggested that prevention network of thalassemia should be established, especially in high prevalent southern Jiangxi (Hakka Han), including establishment of thalassemia database collection, hematological analysis laboratories, genetic counselling clinics, prenatal diagnosis centers and neonatal screening centers.

Lack of association between the CYP1A1 Ile462Val polymorphism and endometrial cancer risk: a meta-analysis.

PURPOSE: Any association between the CYP1A1 Ile462Val polymorphism and endometrial cancer risk remains inconclusive. For a more precise estimate, we performed the present meta-analysis. METHODS: PUBMED, OVID and EMBASE were searched for the studies which met inclusion criteria. Data in all eligible studies were evaluated and extracted by two authors independently. The meta-analysis estimated pooled odds ratio (OR) with 95% confidence interval (CI) for endometrial cancer risk attributable to the CYP1A1 Ile462Val polymorphism. RESULTS: A total of 7 studies were included in this meta-analysis. The results indicated no association between endometrial cancer risk and the CYP1A1 Ile462Val polymorphism (for Val vs Ile allele model [OR 1.09, 95% CI 0.73-1.62]; for Val.Val vs Ile.Ile genotype model [OR 1.54, 95% CI 0.56-4.23]; for (Ile.Val + Val.Val) vs Ile.Ile genotype model [OR 1.08, 95% CI 0.71-1.63]; for Val.Val vs (Ile.Ile + Ile.Val) genotype model [OR 1.46, 95% CI 0.53-4.04]). CONCLUSIONS: This meta-analysis suggests that there is no association between endometrial cancer risk and the CYP1A1 Ile462Val polymorphism.

Vascular endothelial growth factor downregulates apolipoprotein M expression by inhibiting Foxa2 in a Nur77-dependent manner.

OBJECTIVE: We aimed to investigate whether vascular endothelial growth factor (VEGF) influences apolipoprotein M (ApoM) expression and pre-ß-high-density lipoprotin (HDL) formation, and whether forkhead box A2 (Foxa2) and Nur77 are involved in this process. METHODS AND RESULTS: We analyzed the serum VEGF concentrations of 264 adults who underwent a medical checkup and found that VEGF concentration was positively correlated with serum triglyceride, total cholesterol, LDL cholesterol (LDL-C), very-low-density lipoprotein cholesterol (VLDL-C), and ApoB concentrations, but was negatively correlated with serum high-density lipoprotein cholesterol (HDL-C) and ApoM concentrations. We further investigated the effects of VEGF on ApoM expression and pre-ß-HDL formation, and the mechanisms responsible, in HepG2 cells and mouse primary hepatocytes. VEGF markedly downregulated ApoM expression and pre-ß-HDL formation. At the same time, expression of Foxa2 was also inhibited, whereas expression of Nur77 was increased by treatment with VEGF. Furthermore, small interfering (si) RNA knockdown of Foxa2 made the downregulation of VEGF on ApoM expression and pre-ß-HDL formation even more obvious. In addition, siRNA knockdown of Nur77 significantly compensated for the inhibitory effect of VEGF on Foxa2 expression, whereas the Nur77 agonist cytosporone B led to the downregulation of Foxa2 expression more significantly than VEGF. Moreover, overexpression of a Nur77 transgene in C57BL/6 mice resulted in decreased serum ApoM and pre-ß-HDL levels, whereas si-Nur77-treated mice displayed upregulated serum ApoM and pre-ß-HDL levels. CONCLUSION: These results provide evidence that VEGF may first downregulate expression of Foxa2 by enhancing Nur77 activity and then decrease expression of ApoM and pre-ß-HDL formation. Therefore, our study may be useful in understanding the critical effect of VEGF in the pathogenesis of atherosclerosis.

Development and evaluation of a reverse dot blot assay for the simultaneous detection of common alpha and beta thalassemia in Chinese.

Thalassemia is the commonest inherited autosomal recessive disorders of hemoglobin in southern China. We developed and evaluated a reverse dot blot (RDB) assay combined with flow-through hybridization technology platform for the rapid and simultaneous identification of 5 types of α-thalassemia and 16 types of ß-thalassemia common in Chinese. Reliable genotyping of wild-type and thalassemic genomic DNA samples was achieved by means of a gene chip on which allele-specific oligonucleotide probes were immobilized on a nylon membrane. This method involved two multiplex PCR amplification systems of α-thalassemia and ß-thalassemia and one time of hybridization. The whole procedure starting from blood sampling to the identification of thalassemia genotype required less than 4h. The diagnostic reliability of this reverse dot blot assay was evaluated on 427 samples (387 cases of thalassemia and 40 healthy persons) by using direct DNA sequence analysis and gap-PCR in a blind study. These samples included 377 cases of blood, 7 cases of amniotic fluid, 18 cases of chorionic villus, and 25 cases of cord blood. The RDB gene chip was in complete concordance with the reference method. The reverse dot blot assay was a simple, rapid, accurate, and cost-effective method to identify common thalassemia genotypes in the Chinese population.

Simulated microgravity, erythroid differentiation, and the expression of transcription factor GATA-1 in CD34+ cells.

INTRODUCTION: The microgravity environment of spaceflight leads to a series of changes in the human blood system. The aim of the present study was to examine the influence of simulated microgravity on the differentiation of CD34+ cells and to explore whether transcription factor GATA-1, required for the terminal differentiation of committed erythroid progenitor cells, is involved in this process. METHODS: CD34+ cells were cultured in the simulated microgravity conditions created by a rotary cell-culture system (RCCS). The effects of simulated microgravity on the differentiation and apoptosis of CD34+ cells were analyzed using flow cytometry and propidium iodide (PI) staining, respectively. Expression of GATA-1 mRNA in CD34+ cells was determined by real-time quantitative PCR. RESULTS: In the RCCS group, GlyA+ (glycophorin A) expression was lower and CD33+ expression higher than in the 1-g liquid control group (22.21% +/- 3.02% and 60.05% +/- 3.08%, vs. 52.12% +/- 1.92% and 18.87% +/- 1.41%, respectively). The proportion of differentiated cells in the 1-g methylcellulos e group (Gly+% = 54.39% +/- 2.86%, CD33+% = 21.09% +/- 3.19%) was similar to that in the 1-g liquid control group. As shown by real-time quantitative PCR, the relative expression of GATA-1 mRNA in the RCCS group was only 20% of that in the -g control group. CONCLUSIONSs: The differentiation of CD3+ cells, and especially erythroid differentiation, was inhibited by simulated microgravity by a mechanism that appears to involve the suppression of GATA-1 mRNA expression. The results of this study may be useful in understanding the critical effect of simulated microgravity on the pathogenesis of space anemia.

[High mobility group box-1 stimulates proinflammatory cytokine production in endothelial cells via MAP kinases].

OBJECTIVE: To examine the synergistic effect of recombinant human high mobility group box 1 (HMGB1) protein and lipopolysaccharides (LPS) on the release of interleukin-8 (IL-8) and monocyte chemotactic protein 1 (MCP-1) in human umbilic vein endothelial cells (HUVECs), and explore the role of mitogen-activated protein kinases (MAPK) signal transduction in cytokine release. METHODS: HUVECs were incubated with recombinant HMGB1 (0-75 ng/ml) for 24 h and the culture medium supernatant was harvested for detection of IL-8 and MCP-1 with LiquiChip system. At 0, 1, 3, 6, 12 and 24 h after stimulation with 15 ng/ml HMGB1 or 15 ng/ml HMGB1 plus 10 ng/ml LPS, the levels of IL-8 and MCP-1 in the HUVECs were examined. To test the effect of MAPK inhibitors, HUVCs were pretreated with the inhibitors SB203580 (20 mol/L), PD98059 (20 mol/L), and JNK inhibitor II (50 nmol/L) 1 h before HMGB1 and LPS stimulation. RESULTS: The levels of IL-8 and MCP-1 were significantly increased in the HUVECs stimulated with HMGB1 protein at the concentrations of 3, 15 and 75 ng/ml in comparison with the control levels (P<0.01). Since 3-6 h after the stimulation with HMGB1, the levels of IL-8 and MCP-1 began to increase gradually, and steadily increased at 12 and 24 h, all significantly higher than those of the control group (P<0.01). Stimulation of the HUVECs with LPS (10 ng

[Analysis of Toll-like receptor 4 and myeloid differentiation protein-2 interaction with fluorescence resonance energy transfer].

OBJECTIVE: To study the interaction between Toll-like receptor (TLR) 4 and myeloid differentiation protein-2 (MD-2) in living cells using fluorescence resonance energy transfer (FRET) technology. METHODS: The coding sequences of TLR4 and MD-2 (without the signal peptide sequence) were amplified by PCR and cloned into enhanced cyan fluorescence protein (CFP) and enhanced yellow fluorescence protein (YFP) expression vectors carrying TLR4 signal peptides (pECFP-C1-SP and pEYFP-C1-SP). HEK293 cells were transfected respectively or together with the reconstructed plasmids verified by enzyme digestion and sequence analysis, and the expression and sublocalization of these fluorescence proteins in the cells were observed using fluorescence microscope. FRET in the cells coexpressing CFP-TLR4 and YFP-MD-2 was detected using routine and acceptor photobleaching method. RESULTS: The reconstructed plasmids were expressed in HEK293 cells. The cyan or yellow fluorescence was located in the cytoplasm, mainly around the nucleus in the cells transfected with pECFP/TLR4 or pEYFP/MD-2, and both the cyan and yellow fluorescence located mainly in the membrane and occasional in the cytoplasm of cells cotransfected with pECFP/TLR4 and pEYFP/MD-2. Routine or acceptor photobleaching detected FRET phenomena in cells coexpressing CFP-TLR4 and YFP-MD-2, suggesting direct interaction between TLR4 and MD-2. CONCLUSION: This study provides direct evidence of the interaction between TLR4 and MD-2 in living cells.