HMGB1 gene knockout alleviates acute lung injury of sepsis mice via inhibiting TLR4/NF-κB pathway / 安徽医科大学学报

Objective To study the effect of high mobility group box B1(HMGB1)gene knockout on alleviating a-cute lung injury and inhibiting toll-like receptor 4(TLR4)/nuclear factor-KB(NF-κB)pathway of sepsis mice.Methods Wild-type(WT)mice were divided into WT-Sham group and WT-model group,and HMGB1 knockout(KO)mice were divided into KO-sham group and KO-model group.Sepsis ALI model was established by cecal ligation and perforation in WT-model group and KO-model group.Sham operation was performed in WT-Sham group and KO-Sham group.24 h after modeling,the partial pressure of arterial oxygen(PaO2)was detected,oxy-genation index(OI)was calculated,pathological changes of lung tissue were detected and lung injury score was calculated,the concentrations of tumor necrosis factor-α(TNF-α),interleukin-1 β(IL-1 β),interleukin-6(IL-6),reactive oxygen species(ROS),malondialdehyde(MDA),superoxide dismutase(SOD),in serum and lung tissues and the expression of HMGB1,TLR4 and nuclear NF-κB in lung tissues were detected.Results The PaO2,OI and the concentration of SOD in serum and lung tissue of WT-model group were lower than those of WT-Sham group,the lung injury scores,the concentrations of TNF-α,IL-1 β,IL-6,ROS and MDA in serum and lung tissue,and the expression levels of HMGB1,TLR4 and nuclear NF-κB in lung tissue were higher than those in WT-Sham group(P＜0.05).HMGB1 was not expressed in lung tissue of KO-model group,and the concentrations of PaO2,OI and the concentration of SOD in serum and lung tissue of KO-model group were higher than those of WT-model group,the lung injury scores,the concentrations of TNF-α,IL-1β,IL-6,ROS and MDA in serum and lung tissue,and the expression levels of TLR4 and nuclear NF-κB in lung tissue were lower than those of the WT-model group(P＜0.05).Conclusion HMGB1 gene knockout alleviates acute lung injury of sepsis mice,the re-lated molecular mechanism may be the inhibition of TLR4/NF-κB pathway mediated inflammation and oxidative stress.

pH/Temperature Responsive Curcumin-Loaded Micelle Nanoparticles Promote Functional Repair after Spinal Cord Injury in Rats via Modulation of Inflammation

BACKGROUND@#The formation of an inhibitory inflammatory microenvironment after spinal cord injury (SCI) remains a great challenge for nerve regeneration. The poor local microenvironment exacerbates nerve cell death; therefore, the reconstruction of a favorable microenvironment through small-molecule drugs is a promising strategy for promoting nerve regeneration. @*METHODS@#In the present study, we synthesized curcumin-loaded micelle nanoparticles (Cur-NPs) to increase curcumin bioavailability and analyzed the physical and chemical properties of Cur-NPs by characterization experiments. We established an in vivo SCI model in rats and examined the ability of hind limb motor recovery using Basso–Beattie– Bresnahan scoring and hind limb trajectory assays. We also analyzed neural regeneration after SCI using immunofluorescence staining. @*RESULTS@#The nanoparticles achieved the intelligent responsive release of curcumin while improving curcumin bioavailability. Most importantly, the released curcumin attenuated local inflammation by modulating the polarization of macrophages from an M1 pro-inflammatory phenotype to an M2 anti-inflammatory phenotype. M2-type macrophages can promote cell differentiation, proliferation, matrix secretion, and reorganization by secreting or expressing pro-repair cytokines to reduce the inflammatory response. The enhanced inflammatory microenvironment supported neuronal regeneration, nerve remyelination, and reduced scar formation. These effects facilitated functional repair in rats, mainly in the form of improved hindlimb movements. @*CONCLUSION@#Here, we synthesized pH/temperature dual-sensitive Cur-NPs. While improving the bioavailability of the drug, they were also able to achieve a smart responsive release in the inflammatory microenvironment that develops after SCI. The Cur-NPs promoted the regeneration and functional recovery of nerves after SCI through anti-inflammatory effects, providing a promising strategy for the repair of SCIs.

Study on serum perfluoroalkyl and polyfluoroalkyl substances exposure status of community residents in Songjiang District， Shanghai / 上海预防医学

ObjectiveTo investigate the characteristics of serum perfluoroalkyl substances （PFASs） exposure and potential influencing factors among community residents in Songjiang District， Shanghai. MethodsIn August 2021， residents who underwent routine health checkups in a community in Songjiang District， Shanghai were recruited as study subjects. The inclusion criteria were adult residents who had lived in the area for more than 3 years， had no occupational exposure history， no underlying diseases， were not pregnant， and were able to complete the questionnaire independently and sign the informed consent form. A questionnaire survey was conducted and venous blood samples were collected. The concentrations of 15 PFASs in serum were determined using ultra-high performance liquid chromatography-tandem quadrupole mass spectrometry （UPLC-MS/MS）. Ordered multi-class logistic regression， interquartile range （IQR）， and odds ratio （OR） were used to explore the influencing factors and risk magnitude of serum PFASs concentrations. ResultsOf the 15 PFASs， 14 were detected， and the detection rates of 7 PFASs were higher than 50%. The highest detected concentrations among the PFASs were PFOS （perfluorooctane sulfonate）， PFOA （perfluorooctanoic acid）， and PFHxS （perfluorohexane sulfonate）， with median concentrations of 48.61 μg∙L-1， 37.29 μg∙L-1， and 36.51 μg∙L-1， respectively. The strongest correlation was between PFDA and PFUnDA （r=0.93， P<0.05）， followed by PFOS and PFDA （r=0.86， P<0.05）. Age， frequency of plastic product use， time spent indoors per day， personal annual income， tea consumption， and daily water intake were potential factors for exposure to PFASs. Among them， age was positively correlated with PFASs； tea consumption was positively correlated with PFNA and PFOA； PFHpA was negatively correlated with the frequency of plastic product use and personal annual income； and PFOS was negatively correlated with the time spent indoors per day. ConclusionThe exposure to serum PFASs among community residents in Songjiang District was relatively serious， and the main components were traditional PFOA， PFOS， and PFHx. Different sociodemographic characteristics had varying degrees of influence on the concentrations of PFASs in serum. The impact of PFASs exposure on the health of community residents deserves further investigation.

A biomimetic liver cancer on-a-chip reveals a critical role of LIPOCALIN-2 in promoting hepatocellular carcinoma progression

Hepatic stellate cells (HSCs) represent a significant component of hepatocellular carcinoma (HCC) microenvironments which play a critical role in tumor progression and drug resistance. Tumor-on-a-chip technology has provided a powerful in vitro platform to investigate the crosstalk between activated HSCs and HCC cells by mimicking physiological architecture with precise spatiotemporal control. Here we developed a tri-cell culture microfluidic chip to evaluate the impact of HSCs on HCC progression. On-chip analysis revealed activated HSCs contributed to endothelial invasion, HCC drug resistance and natural killer (NK) cell exhaustion. Cytokine array and RNA sequencing analysis were combined to indicate the iron-binding protein LIPOCALIN-2 (LCN-2) as a key factor in remodeling tumor microenvironments in the HCC-on-a-chip. LCN-2 targeted therapy demonstrated robust anti-tumor effects both in vitro 3D biomimetic chip and in vivo mouse model, including angiogenesis inhibition, sorafenib sensitivity promotion and NK-cell cytotoxicity enhancement. Taken together, the microfluidic platform exhibited obvious advantages in mimicking functional characteristics of tumor microenvironments and developing targeted therapies.

Sugar sweetened beverage knowledge and consumption among third grade primary students in Nanjing / 中国学校卫生

Objective@#To explore the knowledge and consumption of sugar sweetened beverage(SSB) and its influencing factors among third grade primary students, to provide basis for take targeted intervention measures.@*Methods@#In September 2019, 1 686 primary school students of grade 3 were randomly selected from 2 primary schools in 1 urban area and 1 outer suburb area of 12 districts in Nanjing by using a multistage cluster sampling method，and a self administered questionnaire were offered to them to collect the knowledge about sugar sweetened beverage and its intake.@*Results@#Totally 753 students (44.7%) answered 6 or more SSB knowledge questions correctly, and the rate of 389 students (50.2%) in urban areas was higher than that of 364 students (40.0%) in suburban areas. There were 780 (46.3%) students who knew that dairy containing beverage could not replace milk, the rate of 403 (52.0%) students in urban area was higher than that of 377 (41.4%) students in suburban area (χ 2=17.76, 18.99, P<0.05). Logistic regression analysis showed that compared with the frequency of consumption of SSB <1 time per week, the behavioral risk factors of primary school students who drink SSB ≥4 times per week were:urban area (OR=1.55), low parents educational level (OR=2.44), and frequent storage of SSB at home (OR=1.62). The protective factors were as follows:duration of extracurricular physical activity <120 min/week (OR=0.68), video time <120 min/day (OR=0.50), awareness rate of SSB ≥60% (OR=0.75), and restriction of high sugar snacks by parents (OR=0.60).@*Conclusion@#The knowledge associated with SSB among third grade students in Nanjing is relatively low. Consumption of SSB has been influenced by areas, parents educational level, knowledge about SSB and family factors. SSB consumption among primary students should be interfered at the school and family level. The health food education need to carry out based on the school and family, so as to create a supportive atmosphere integrating the school family to drink less sugar beverages.

Research progress on exposure levels and toxic pathways of typical persistent organic pollutants in foods / 中华预防医学杂志

Dioxins, polybrominated diphenyl ethers, and benzo(a)pyrene are common organic pollutants in food. They have been of concern to academics and government administrations due to high residue and persistence, easy accumulation and strong harmful effects. The National Research Council of the United States of America published Toxicity Testing in the 21st Century: A Vision and Strategy in 2007, which proposed a new concept of toxicity testing that toxicity testing should take full consideration of population exposure data and base on in vitro tests, human cell lines, toxicity pathways and high-throughput screening. Meanwhile, systems biology, bioinformatics and rapid assay technologies will be used to better understand toxicity pathways—the cellular response pathways that can lead to adverse health effects when sufficient perturbing induced by chemicals exposure. The new toxicity testing strategy has changed the traditional testing pattern and has brought a wide impact on the international relevant fields. The European Union, the World Health Organization, and the United States Environmental Protection Agency, the Food and Drug Administration, and the National Center for Toxicological Research have organized relevant discussions and exploratory studies to address the new toxicity testing concept and how to evaluate and utilize the results of traditional toxicity test researches. Compared to the discussion, 'whether to do it’, ten years ago, the question, 'how to do it’, has become the concern of the current discussion. Therefore, how to respond to the concept of toxicity testing and how to effectively utilize and excavate traditional toxicity test data have been the focus of multi-disciplines and interdisciplinary academia such as toxicology, food hygiene and environmental science. Therefore, this article provides an overview of the exposure levels of dioxin, polybrominated diphenyl ethers and benzo[a]pyrene, which are typical persistent organic pollutants in food in China and the current research status of toxic pathways based on whole animal experiments. The exposure level, toxic effect and toxicity mechanism of three contaminants are analyzed and summarized in order to provide basis for future results based on the 21st century toxicity test compared with traditional tests and data mining analysis of these two kinds of data. Meanwhile, it also lays the foundation for the establishment of a toxicity testing framework based on exposure characteristics, toxic pathways, and biomarkers.

Management and safety assessment of nanomaterials in food: status and prospects / 中华预防医学杂志

The safety assessment of nanomaterials in food is essential for safeguarding supervision and maintaining public health. However, there are still no safety assessment procedures for nanomaterials established in national-level in China and no specific toxicology and safety assessment procedures about nanomaterials for food, too. These factors lead to restriction on food safety protection and supervision. Current methods of evaluating the safety of nanomaterials mainly rely on traditional toxicological assessment that are extrapolated based on animal experiment from high doses to low doses and from animals to humans. These uncertainties restrict the accuracy of safety assessment for nanomaterials and also limit the development of scientific and effective evaluation procedures and regulatory measures. Currently, the key issues need to be solved including exposure assessment and evaluation methods of nanomaterials in food and the established methods of the toxicity test for nanomaterials that are consistent with the objectives of toxicity test in the 21st century vision and strategy. In this article, we reviewed current administrative regulatory, situations, and existing issues of food nanomaterials either in China or some developed countries in order to provide a scientific basis in establishing safety assessment procedures for nanomaterials in food in the future.

Metagenomic analysis of symbiotic microorganism in sailors with long sea voyage / 国际检验医学杂志

Objective To investigate the influence of long sea voyage working environment on the symbiotic microorganisms and their relationship with their hosts .Methods The periumbilical microbial sam-ples from the operating workers of long sea voyage before and after operation were collected .Then 16S rRNA V4 section amplification ,sequencing and whole metagenome shotgun high-throughput sequencing were per-formed .Moreover the bacterial community structure ,kinds and microorganism metabolic function change were analyzed .The peripheral blood was collected from the workers of long sea voyage operation and shore-based operation for conducting the blood routine analysis .Results After 105 d ocean sailing ,the diversity of perium-bilical microbial community in the workers with long sea voyage operation decreased and the relative abun-dance of Firmicutes increased ,w hile w hich of Proteobacteria decreased ;w hich of Staphylococcus increased , while which of Corynebacteria decreased ,the differences were statistically significant (P<0 .05) ,the relative a-bundance of pathogenic bacteria or conditional pathogenic bacteria ,especially Staphylococcus epidermidis and Staphylococcusaureus aureus ,increased significantly .T he functional gene analysis indicated that the expres-sion of periumbilical microbial infection related genes increased after the long sea voyage operation .Compared with shore-based operation workers ,the proportion of workers with peripheral blood lymphocytes abnormal elevation in the long sea voyage group increased significantly ,the difference was statistically significant (P<0 .05) .Conclusion The periumbilical skin symbiotic microorganisms may reflect the health conditions in the workers with long sea voyage operation .

Quantitative structure-activity relationship prediction of carcinogenicity of N-nitroso compounds based on category approach and read-across / 中华预防医学杂志

Objective@#New quantitative structure-activity relationship (QSAR) method was used to predict N-nitroso compounds (NOCs) carcinogenicity. This could provide evidences for health risk assessment of the chemicals.@*Methods@#Total 74 chemical substances of NOCs were included as target chemicals for this validation study by using QSAR Toolbox based on category approach and read-across. The included 74 NOCs were categorized and subcategorized respectively using "Organic functional groups, Norbert Haider " profiler and "DNA binding by OASIS V.1.1" profiler. Carcinogenicity of rat were used as target of prediction, the carcinogenicity@*results@#of analogues in chemical categories were cross-read to obtain the carcinogenic predictive results of the target chemicals. Results 74 NOCs included 26 nonclic N-nitrosamines, 24 cyclic N-nitrosamines and 24 N-nitrosamides The sensitivity, specificity and concordance of the category approach and read-across for predicting carcinogenicity of 74 NOCs were 75% (48/64), 70%(7/10) and 74% (55/74) respectively. The concordance for noncyclic N-nitrosamines, cyclic N-nitrosamines and N-nitrosamides were 88% (23/26), 71% (17/24) and 63% (15/24) respectively.@*Conclusion@#QSAR based on category approach and read-across is good for prediction of NOCs carcinogenicity, and can be used for high-throughput qualitative prediction of NOCs carcinogenicity.

Osteogenic ability study on co-culture of adipose-derived mesenchymal stem cells and bone marrow mesenchymal stem cells / 中华骨科杂志

Objective To assess the osteogenic ability after co-culture BMSC and ADSC in vivo and in vitro.Methods ADSC and BMSC were obtained by adherent screening method and enzymatic digestion method.Flow cytometry was used to confirm the phenotypes of ADSC and BMSC.Oil red O was used to induce MSC to fat.Alkaline phosphatase (ALP) and alizarin red staining were used in osteogenic group.This sample was divided into four groups,no-induced stem cells group;BMSC osteogenic induction group;ADSC osteogenic induction group;co-culture of BMSC and ADSC osteogenic induction group.ALP activities and Calcium absorbance were determined during different periods of osteogenic introduction.OCN and Runx2 expression level were tested via RT-PCR and western blot methods after osteogenic induction for 2 weeks.Furthermore,cells in each group were seeded on HA/CS/PLLA composite scaffolds,and the scaffolds with cells were planted into bone defects in rat models.The rats were sacrificed by overdose anesthesia at 8 weeks after surgery and the scaffolds were removed for further analysis.Results Oil red O staining demonstrated red after adipogenic induction.Alkaline phosphatase and Alizarin red staining showed flaky red under condition of osteogenic induction.There had no statistical change among each group after osteogenic induction for 3 days,and ALP activity significantly increased after osteogenic induction for 5 days.Meanwhile,the ALP activity in co-culture of BMSC and ADSC group was markedly higher than the other three groups.However,there had no significant change in A value of calcium absorbance among each group after osteogenic induction for 7 days,while it increased at 14th day and ALP activity in co-culture of BMSC and ADSC group was significantly higher than the other three groups.After osteogenic induction for 2 weeks,the mRNA expression of OCN and Runx2 in co-culture of BMSC and ADSC group was 78.24±8.11 and 1 180.13±121.16 respectively,and the protein expression of OCN and Runx2 was 6.54±0.59 and 4.43±0.51.These mRNA and protein expression level in co-culture of BMSC and ADSC group enhanced significant compared with the other 3 groups.Histological assay demonstrated that the new bone tissues formed in co-culture of BMSC and ADSC group were 497.75±7.44 μm2,which was larger than that in the other 3 groups at 8 weeks after implantation.Conclusion Co-culture BMSC and ADSC may up-regulated the osteogenic ability in vivo and in vitro.

Triptolide induces apoptosis of human acute T lymphocytic leukemia Jurkat cells via inhibiting transcription of human endogenous retrovirus HERV-K Np9 gene / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the molecular?mechanisms by which triptolide induces apoptosis of human acute T lymphocytic leukemia Jurkat cells.</p><p><b>METHODS</b>MTT assay was employed to detect the proliferation inhibition of Jurkat cells by triptolide, and the IC50 was calculated by OriginPro8. Flow cytometry was used to analyze apoptosis of Jurkat cells. Np9 mRNA levels were detected by RT-PCR and analyzed quantitatively by Kodak 1D 3.6 software. Correlation between the inhibition of Np9 transcription and the cell apoptosis was analyzed by SPSS 19.0.Western blotting was employed to determine Np9 downstream signaling molecules c-myc, β-catenin, ERK, AKT and Notch1 protein level in Jurkat cells after exposure to different concentrations of triptolide for 48 h.</p><p><b>RESULTS</b>Triptolide treatment resulted in dose-dependent inhibition of Jurkat cells proliferation and its IC50 was 12.7 nmol/L. Triptolide induced apoptosis of Jurkat cells in dose- dependent manner. Furthermore, triptolide inhibited Np9 mRNA transcription level in Jurakt cells in a dose-dependent manner. There was a correlation between the triptolide-mediated the apoptosis and the inhibition of Np9 transcription of Jurkat cells (R(2)=0.907). Western blotting results displayed that triptolide inhibited transcription levels of Np9 mRNA with a concomitant decrease of its downstream signaling molecules c-myc, β-catenin, ERK, AKT and Notch1 at protein levels.</p><p><b>CONCLUSION</b>Inhibition of HERV-K Np9 mRNA and its downstream signaling molecules c-myc, β-catenin, ERK, Akt and Notch1 protein might be one of important molecular?mechanisms by which triptolide induces apoptosis of human acute T lymphocytic leukemia Jurkat cells.</p>

Construction of a GFP/Puro double-labeled lentiviral vector containing CK8 interfering RNA and its effect on cell apoptosis in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct a GFP/Puro double-labeled lentiviral expression vector for CK8 silencing and assess the effects of CK8 silencing on cell apoptosis.</p><p><b>METHODS</b>The siRNA sequences of CK8 were inserted into the lentiviral expression vector GV248 and transfected into 293T cells with the packaging plasmids PMD and SPA. The lentivirus was collected at 24 and 36 h post-transfection. Flow cytometry was used to detect the virus titer and the positive cells were selected with puromycin. The knockdown of CK8 was examined by Western blotting. The effect of CK8 down-regulation on cell apoptosis induced by cisplatin was detected with Annexin V/PI staining.</p><p><b>RESULTS AND CONCLUSION</b>We successfully constructed CK8 interference lentiviral vector and obtained a stable cell line with CK8 knock-down that was sensitive to cisplatin-induced apoptosis.</p>

The action of p38 and ERK1/2 on differentiation into neuron-like cells from rhesus monkeys mesenchymal stem cells / 中华显微外科杂志

ObjectiveTo investigate the role of p38 and ERK1/2 during rhesus monkeys mesenchymal stem cells differentiated into neuron-like cells.MethodsTo induce the neuronal phenotype,rhesus monkeys mesenchymal stem cells were maintained in sub-confluent cultures in serum-contain medium supplement with Sonic hedgehog.Western blot analysis the change of p38 and ERK1/2 during rhesus monkeys mesenchymal stem cells differentiated into neuron-like cells.Under transmission and scanning electron microscope,ultra-structure of the differentiated cell were observed.ResultsDuring BMSCs differentiated into neuron-like cells by SHH,Mitogen-activated protein kinases (MAPK) involved in their signal transduction,p38 was activated and ERK1/2 was inhibited.P38 inhibitor SB203580 increased induced differentiation time compared with normal induced cells,and inhibited neurite outgrowth.ConclusionActivation of p38 and inhibition of ERK was impacted on differentiation into neuron-like cells from rhesus monkeys mesenchymal stem cells induced by Sonic hedgehog,which may has potential application on neuroprotection of stem cells in Nervous system diseases

Differentiation of rhesus monkey mesenchymal stem cells into neuron-like cells by sonic hedgehog factor / 中国组织工程研究

BACKGROUND:Bone marrow mesenchymal stem cells(BMSCs)differentiating into neural cells is an effective way of cell therapy of nervous system disease.However,the methods used nowadays still need to be improved.OBJECTIVE:To induce the differentiation of rhesus monkey BMSCs into neuron-like cells by using sonic hedgehog factor.METHODS:Rhesus monkey BMSCs differentiating into neuron-like cells was induced by typical retinoic acid and sonic hedgehog factor.Rhesus monkey BMSCs were isolated and cultured by density gradient centrifugation method.Cell growth was observed under an inverted phase contrast microscope and cell growth curve was determined using MTT assay.Flow cytometry was performed to characterize the phenotype of BMSCs,and immunohistochemistry was utilized to assess differentiated cells.Ultra-structure of the differentiated cells was observed by transmission and scanning electron microscopes.RESULTS AND CONCLUSION:Rhesus monkey BMSCs cultured in vitro were identified by flow cytometry,with high homogenicity.Following sonic hedgehog factor disposal for 7 days,differentiated cells were mainly positive for neurone specific enolase,neurofilament protein,Tau and glial fibrillary acidic protein(GFAP).Image statistical analysis found that in sonic hedgehog factor scheme,neural stem cells marker Neetin positive rate was significantly higher compared with the rstinoic acid scheme(P＜0.01).GFAP-positive rate was greater in the retinoic acid scheme than in the sonic hedgehog factor scheme(P＜0.05).Results indicated that sonic hedgehog factor scheme is an effective pathway of rhesus monkey BMSC differentiation into neuron-like cells.

Differentiation of rhesus monkey bone marrow mesenchymal stem cells into neuron-like cells induced by sonic hedgehog: Significance of its signal molecule expression changes compared with retinoic acid scheme / 中国组织工程研究

BACKGROUND: Present studies have demonstrated that during neural development, differentiation of neural stem cells (NSCs) was affected by various regulatory factors from surrounding microenvironment. Sonic hedgehog (Shh) is a key induction signal during neural fetal development, and can be an effective inductor to regulate differentiation of neural cells. OBJECTIVE: To investigate the signal transduction pathway of SHH for differentiation of rhesus monkey bone marrow mesenchymal stem cells (BMSCs) into of neuron-like cells by sonic hedgehog factor. METHODS: Rhesus monkey BMSCs were isolated and cultured by conventional density gradient centrifugation. BMSCs in the induction group were treated with L-DMEM containing FGF2, B27 and fetal bovine serum for preinduction of 24 hours, and then with DMEM supplemented with 0.5 μmol/L retinoic acid or 400 μmol/L SHH for 8 days. Non-induced cells served as control group. Following labeling with neuron enolase, positive cells were screened by flow cytometry. RT-PCR and Western-blot were used to detect SHH- and retinoic acid-induced cell membrane receptor and intracellular signal protein changes. RESULTS AND CONCLUSION: SHH specific membrane receptor Ptc, retinoic acid specific receptor RARα, signal protein molecule ptch1 and Smad expressed in normal cells. Ptc expression upregulated in SHH-induced cells. High expression lasted for a long time with induction time, which was significantly stronger compared with the retinoic acid and control groups (P < 0.01). Intracellular ptch1 protein molecule expression showed similar tendency as this, but could not induce upregulation of RARα expression. During induction, retinoic acid-stimulated cells did not activate Ptc pathway. Four days following induction, RARα expression upregulated and lasted till 6 days, but there were no significant differences. No significant change in ptch1 expression was determined. SHH- and retinoic acid-induced cell Smad molecule expression upregulated, but no significant difference was determined. Results verified that SHH-induced scheme participated in cell induction and differentiation by persistently activating its specific receptors. However, there was no significant receptor pathway crossing between retinoic acid-induced and SHH-induced schemes.

Diagnosis of uterine leiomyoma by MRI / 中华放射学杂志

Objective To investigate the MR features of uterine leiomyomas and evaluate its diagnostic value. Methods Twenty six patients with probable uterine leiomyomas underwent preoperative ultrasound, T 1 weighted spin echo and T 2 weighted fast spin echo MR examinations. Among them, 11 cases were performed with dynamic contrast enhancement. Comparative analysis between MRI findings and pathologic results was done. Results MRI diagnosis in all cases was consistent with the results given by surgery and pathology, except 2 being pathologically proven as endometrial polyp or inflammatory pseudoplasma. The diagnostic accuracy of MRI was 92%, while the accuracy of ultrasound was 85%. The difference between the number of lesions detected by two modalities had statistical significance (89% for MRI vs 69% for ultrasound, ? 2=17.86, P