Study on methylation of p15 INK4B in myelodysplastic syndrome

AIM: To investigate the variation and distribution of abnormaly methylated p15 INK4B in myelodysplastic syndrome (MDS) and its subgroups. METHODS: The abnormal methylation of p15 INK4B in 32 cases with MDS was studied using methylation-specific PCR (MSP). RESULTS:The positive rate of abnormal methylation of p15 INK4B was about 50% in MDS. The ratios in subtypes were: 0% (0/6) in RA,20% (1/5) in RA-S,57.1% (4/7) in RAEB,74.1% (5/7) in CMML,85.7% (6/7) in RAEB-t, respectively.It was worth noticing that 4 cases represented abnormal methylation of p15INK4B during their transformation and progression into AML. CONCLUSION:The abnormal methylation in p15 INK4B might be one of the causes of MDS, which was related to pathologial process of MDS.Every subtype was not solitary classification completely. Abnormal methylation of p15 INK4B was apt to occur accompanying the progression and transformation of the subtypes.     

Urban forests and social inequality in the Pacific Northwest

Research has shown there is a positive relationship between urban greenness and the well-being of city residents. But greenness is often unevenly distributed across a city, raising environmental justice issues. In 2011 and 2012 the USDA Forest Service, Forest Inventory and Analysis program installed ground plots in the urbanized areas of Oregon and Washington. We analyze these data for the urban areas west of the Cascade Mountains, linking it with demographic data from the U.S. Census to examine the relationship between greenness and socioeconomic status at a sub-regional scale. To explore some relations between urban forest measures and socioeconomic conditions and measures we developed four models: presence of tree canopy cover with a logistic mixed model, and on a subset of the data, percent tree canopy cover with a linear mixed model and tree count and tree species count with Poisson mixed models. We found that median household income, house value, land use, and years in the Tree City USA program contributed to explaining measures of greenness, such as canopy cover presence, percent canopy cover, tree counts, and tree species counts. This agrees with other studies, but does so at a broad scale covering the most densely populated areas in the Pacific Northwest.     

Application of artificial intelligence for tree risk assessment optimization in Itanhaém – São Paulo,Brazil

Tree risk assessment consists of the identification of a set of defects that may affect the stability of the tree, leading to a possible collapse or failure, either of the whole plant or a part of it; and also, the identification of the targets to be reached and the side effects caused by any eventual failure. Although this is a necessary practice, the large number of variables involved in this evaluation makes the analysis time-consuming. Thus, this research aimed to optimize the tree risk assessment by creating a new protocol with the three visual assessment methods common variables and generating a new protocol applied to trees of species frequently used in urban afforestation worldwide: Terminalia catappa, Ficus Benjamin and Delonix regia. Altogether 36 variables were used for tree risk visual assessment applied in the evaluation of 230 trees located in the urban forest in Itanhaém - São Paulo - Brazil. The data collection was carried out using a smartphone and a data spreadsheet created in ODK collect app, facilitating data storage and processing. To identify the variables with the greatest possibility to determine the risk of falling, artificial intelligence was used through the Decision Tree algorithm (C4.5) in the WEKA software. The results showed that, from the 36 variables evaluated, 14 were enough to determine the risk of tree falling, with 73% hit rate in the tree risk classification. It is concluded that the use of artificial intelligence was essential in detecting tree problems in order to redirect management practices.     

Exercise training attenuates hypertension progression via activation of central ACE2-Ang(1-7)-Mas axis in prehypertensive rats

AIM: To investigate the effects of exercise training on the progression from prehypertension to hypertension, blood pressure regulation and the angiotensin-converting enzyme 2 (ACE2)-angiotensin (Ang) (1-7)-MAS axis activation in cardiovascular centers, and to elucidate the central mechanisms of exercise training postponing hypertension progression. METHODS: The male spontaneously hypertensive rats (SHR; n=20, 5 weeks old) and normotensive Wistar Kyoto (WKY) rats (n=20) were randomly assigned to sedentary (Sed) group and exercise training (ExT) group. The trained rats run on a treadmill in moderate-intensity for 20 weeks. Systolic blood pressure (SBP) was measured by tail-cuff method. The baroreflex sensitivity (BRS) was assessed by intravenous injection of phenylephrine. The expression of ACE2 and MAS receptor at mRNA and protein levels in baroreflex centers were determined by real-time PCR and Western blot, respectively. Alterations of BRS were evaluated before and after intracerebroventricular injection of MAS receptor agonist Ang (1-7) and its antagonist A779, respectively. RESULTS: Compared with SHR+Sed group, exercise training since prehypertension significantly postponed the development of hypertension, delayed the hypertension progression, and decreased SBP in both SHR and WKY rats (P<0.05). Exercise training enhanced blood pressure regulation and improved the BRS in SHR (P<0.01). The expression of ACE2 and MAS receptor at mRNA and protein levels in the baroreflex centers (rostral ventrolateral medulla, nucleus tract solitarius and paraventricular nucleus) were up-regulated in SHR+ExT group (P<0.05). Central administration of A779 abolished the benefits of exercise-induced improvement of BRS in SHR+ExT group (P<0.01). In contrast, Ang(1-7) improved the BRS in both SHR+Sed group and SHR+ExT group (P<0.05). CONCLUSION: Exercise training postpones hypertension progression and improves blood pressure regulation, which may be associated with the activation of central ACE2-Ang(1-7)-Mas axis.     

Overexpression of two plastidial fatty acid desaturase genes from tree peony affects the ratio of α-linolenic acid to linoleic acid in Arabidopsis seeds

Tree peony (Paeonia section Moutan DC.) has recently been recognised as an important woody oil plant of high economic value, with its seeds containing high levels of α-linolenic acids (ALA, C18:3). Here, we identified two novel FA desaturase genes from Paeonia. rockii, designated PrFAD6 and PrFAD7. Sequence, structure, and phylogenetic analyses revealed that they share high similarity with ω-6 and ω-3 plastidial FA desaturases. qRT-PCR showed that PrFAD6 and PrFAD7 were expressed in all studied tissues, particularly high in stamen, pistil, seed and leaf. Heterologous expression of PrFAD6 in Arabidopsis resulted in a 2.3–2.9% reduction in the ratio of ALA to linoleic acid (LA, C18:2), whilst overexpression of PrFAD7 increased the ALA/LA ratio by 7.0–9.9%. Moreover, the transgenic Arabidopsis plants overexpressing PrFAD6 and PrFAD7 exhibited varied abundances of a few FA components, particularly increased C18:2 and C18:3 levels, respectively. These results support the biological role of PrFAD6 and PrFAD7 in the biosynthesis of ALA and LA in tree peony seeds. Our study is the first attempt to verify the functions of plastidial FA desaturases in tree peony and will facilitate future research and industrial utilisation of tree peony as an important oil plant.     

Geostatistical analysis to identify characteristics involved in sewer pipes and urban tree interactions

Tree roots cause significant and costly damage to sewer systems. However, the contributions made by tree and sewer characteristics to sewer system damage are not yet well understood. Previous research has proved inconclusive and there is a lack of agreement on the importance of the variables involved, which means that the results cannot be extrapolated globally. This study presents a methodology to improve the understanding of tree root-sewer conflicts through a geostatistical analysis of a tree inventory and CCTV video fault reports. The methodology is applied to a 11 km² case study in Bogotá, Colombia. The analysis used tree and sewer pipe georeferenced data, principal component analysis, and linear, Logit, and Poisson regression models. The proposed methodology identifies the pipe characteristics and the tree species most responsible for the root intrusion events into sewers. As expected, larger trees are prone to cause more pipe damage; therefore tree-pipe distance is a relevant parameter control for reducing potential deterioration. Cumulative precipitation and pipe length showed no effect on observed root intrusion events, and pipes made from brick had higher odds to present root intrusion in contrast with concrete pipes. The presented methodology uses readily available information and software, and can be modified depending on the requirements of each particular case study. This approach will therefore allow for more efficient use of costly, site-specific pipe investigations, and is especially useful for cases where there is a general lack of knowledge regarding the characteristics that favour the negative interactions between pipes and tree roots.     

The image recognition of urban greening tree species based on deep learning and CAMP-MKNet model

The information of urban tree species resources is of vital significance to the planning and design of urban green spaces. Tree organs, such as the bark are used as the primary features of identifying tree species. However, traditional tree identification methods need to consume a lot of manpower and time costs. In addition, the application of machine image recognition technology to tree species recognition still has problems such as heavy data preprocessing workload, small number of tree species images, uneven distribution of categories, and low recognition accuracy. In order to promote the intelligent management of urban forestry and solve the above problems, it is necessary to establish an automatic image recognition model for urban greening tree species. We captured bark images of 21 urban afforestation tree species in their natural environment and constructed a dataset that was divided into a train set, validation set, and test set in the ratio of 7:1:2. Combining Channel Attention Module (CAM) with algorithms such as Spatial Pyramid Pooling (SPP) and Mixed Depthwise Dilated Convolutional Kernels. The core algorithm is Mixed Convolution Kernel (MK), and a CAMP-MKNet Convolutional Neural Network (CNN) is constructed as a bark image classification model for urban greening tree species. The overall accuracy of the generic models ranged from 41.06% to 82.03%, whereas the overall accuracy of the experimental CAMP-MKNet model was 84.25%, with lower prediction cost. Our study shows that the CAMP-MKNet CNN model with better prediction performance and computational cost and can provide crucial insights and technical support for developing automated urban tree species image recognition systems.     

Expression and clinical significance of PTEN and survivin in laryngeal squamous cell carcinoma

AIM: To investigate the expression and clinical significance of phosphatase and tensin homology deleted on chromosome ten (PTEN) and survivin in laryngeal squamous cell carcinoma (LSCC) and the relationship between the two genes. METHODS: The expression of PTEN and survivin in 57 cases of LSCC, 27 cases of adjacent safety margin (ASM) radomized drawn from the LSCC patient and 22 cases of vocal cord polyp (VCP) were evaluated by SP immunohistochemistry, and the statistics analysis were followed. RESULTS: The positive rates of PTEN in LSCC, ASM and VCP were 89.5％ (51/57), 88.9％(24/27) and 95.5% (21/22), respectively. There was no significant difference among them (P>0.05), but the expression degrees were ascending (P<0.01). There was no expression of survivin in VCP. The positive rates of survivin in LSCC and ASM were 50.9% (29/57) and 11.1% (3/24) respectively with the significant difference (P<0.01). However, the difference of the expression degrees between LSCC and ASM was not significant (P>0.05). The expression of neither PTEN nor survivin was related to gender, age, tumor site, differentiation, T classification, clinical stage, nodal metastases, etc (P>0.05). There was no correlation in LSCC between PTEN and survivin expression (r=-0.15, P>0.05). CONCLUSIONS: During the carcinogenesis of LSCC, partial variation maybe occurs in PTEN. Survivin probably plays an important role during the carcinogenesis of LSCC. These changes are the early molecular event of the carcinogenesis. Relationship between PTEN and survivin and the biological behavior of LSCC, such as progression, metastases were not observed.     

Modeling height-diameter relationship for artificial monoculture Metasequoia glyptostroboides in sub-tropic coastal megacity Shanghai,China

Tree height is a key variable in forest monitoring studies and for forest management. However, tree height measurement is time consuming, and the recommended procedure is to use estimates from tree height (H) - diameter at breast height (DBH) models. Increasingly, H-DBH models are being developed for urban forests, providing tools to forest management and ecosystem services estimation. Here, we compared model forms and approaches for predicting H as a function of DBH and additional stand level covariates variables. Four model forms were evaluated: (i) basic models (which only used DBH as predictor variable); (ii) generalized models (which used DBH and other predictor variables based on the best basic model); (iii) a mixed-effects model based on the best basic model; and (iv) a mixed-effects model based on the generalized model. Several sampling designs aimed at minimizing height measurement were tested in terms of accuracy and applicability. Taking predicted accuracy and investigation cost into account, we recommend generalized non-linear mixed-effects model (NLME) when there were two or less tree height measurements taken in a given stand. The basic NLME model could be calibrated when there were 3 or more tree height measurements, depending on the required level of accuracy and investigation cost. Additionally, we first reported that soil pH as a covariate variable in H-DBH model and our generalized NLME model implied that the difference in the H-DBH relationship caused by pH varies among different stands. This finding may be attributable to differing biological properties of the similar alkaline tolerance species.     

Effect of miR-7-5p targeting Itch gene on insulin resistance model of HepG2 cells

AIM:To preliminarily explore the relationship between microRNA-7-5p (miR-7-5p) and Itch gene and their relationship with insulin resistance by establishing insulin resistance model of HepG2 cells in vitro for detecting differential expression of miR-7-5p and its predicted target gene Itch in the state of insulin resistance. METHODS:The insulin resistance model of HepG2 cells was induced by suitable concentration of plamitic acid. The possible target genes and the associated signaling pathways of miR-7-5p were predicted based on bioinformatic analysis. The expression levels of miR-7-5p and Itch were detected by RT-qPCR and Western blot in the HepG2 cells with insulin resistance. RESULTS:The HepG2 cell model of insulin resistance was successfully induced by treatment with 0.25 mmol/L palmitic acid for 24 h. Compared with negative control group, the expression level of miR-7-5p detected by RT-qPCR in insulin resistance group was significantly decreased (P<0.01). Bioinformatic analysis showed that a considerable number of target genes of miR-7-5p were enriched in the ubiquitin proteasome system. Among them, E3 ubiquitin ligase Itch gene was the most relevant target gene to insulin resistance. The results of Western blot showed that the protein expression of Itch was up-regulated in the HepG2 cells under insulin resistance (P<0.01). CONCLUSION:miR-7-5p may be involved in the pathophysiological process of insulin resistance, which may directly or indirectly affect the normal transduction of insulin signaling pathway by targeting Itch gene.     

Assessing the performance of urban forest carbon sequestration models using direct measurements of tree growth

Across cities worldwide, people are recognizing the value of greenspace in ameliorating the health and well-being of those living there, and are investing significant resources to improve their greenspace. Although models have been developed to allow the quantification of ecosystem services provided by urban trees, refinement and calibration of these models with more accurate site- and species-specific data can increase confidence in their outcomes. We used data from two street tree surveys in Cambridge, MA, to estimate annual tree mortality for 592 trees and diameter growth rates for 498 trees. Overall tree turnover between 2012 and 2015 was relatively low (annualized 3.6% y⁻¹), and mortality rate varied by species. Tree growth rates also varied by species and size. We used stem diameter (DBH) and species identity to estimate CO₂ sequestration rates for each of 463 trees using three different model variations: (1) i-Tree Streets, (2) Urban Tree Database (UTD) species-specific biomass allometries and growth rates, and (3) empirically measured growth rates combined with UTD biomass allometries (Empirical + UTD). For most species, the rate of CO₂ sequestration varied significantly with the model used. CO₂ sequestration estimates calculated using i-Tree Streets were often higher than estimates calculated with the UTD equations. CO₂ sequestration estimates were often the lowest when calculated using empirical tree growth estimates and the UTD equations (Empirical + UTD). The differences among CO₂ sequestration estimates were highest for large trees. When scaled up to the entire city, CO₂ sequestration estimates for the Empirical + UTD model were 49.2% and 56.5% of the i-Tree Streets and UTD estimates, respectively. We suggest future derivations of ecosystem service provision models allow localities to input their own species-specific growth values. By adding capacity to easy-to-use tools, such as i-Tree Streets, we can increase confidence in the model output.     

Spatial patterns of a subtropical,coastal urban forest: Implications for land tenure,hurricanes, and invasives

Spatial patterns of tree structure and composition were studied to assess the effects of land tenure, management regimes, and the environment on a coastal, subtropical urban forest. A total of 229 plots in remnant natural areas, private residential, public non-residential, and private non-residential land tenures were analyzed in a 1273 km² study area encompassing the urbanized portion of Miami-Dade County, USA. Statistical mixed models of structure, composition, location, and land tenure data were used to analyze spatial patterns across the study area. A total of 1200 trees were measured of which 593 trees (49%) were located in residential areas, 67 (6%) in public non-residential areas, 135 trees (11%) in private non-residential areas, and 405 (34%) in remnant, natural areas. A total of 107 different tree species belonging to 90 genera were sampled. Basal area in residential land tenures increased towards the coast while private residential land tenures and natural areas had higher species diversity than non-residential areas. Tree height, crown light exposure, and crown area might indicate the effects of past hurricane impacts on urban forest structure. Land tenure, soil types, and urban morphology influenced composition and structure. Broadleaf evergreen trees are the most common growth form, followed by broadleaf deciduous, palms, and conifers. Exotic tree species originated mainly from Asia and 15% of all trees measured were considered exotic-highly invasive species. We discuss the use of these results as an ecological basis for management and resilience towards hurricane damage and identifying occurrence of invasive, exotic trees.     

Sodium glycididazole combined with cisplatin efficiently promotes p21 expression in lung adenocarcinoma

AIM:To investigate the effect of sodium glycididazole (CMNa) on the sensitivity of lung adenocarcinoma to cisplatin. METHODS:The microarray data of human lung adenocarcinoma A549 cells treated with cisplatin from NCBI public database were reanalyzed for searching the genes with significantly differential expression. The A549 cells were used in the study and treated with CMNa+cisplatin. The expression levels of the verified candidate genes from database searching were detected by real-time PCR. The role of CMNa in the expression of p21 and its upstream target p53 was also determined. RESULTS:A list of candidate genes from the microarray dataanalysis was obtained, in which p21 was verified in A549 cell line treated with cisplatin by database searching and analyzing. A549 cells were treated with CMNa and cisplatin, and p21 expression was enhanced in the cells treated with CMNa+cisplatin but not CMNa alone. In addition, enhanced p21 expression in A549 cells treated with CMNa+cisplatin was mediated by promotion of the upstream p53 level. CONCLUSION:CMNa co-operates with cisplatin to improve p21 expression in human lung adenocarcinoma, which is mediated through enhancement of the p21 upstream target p53, indicating another new insight of CMNa function in radiosensitivity of human lung adenocarcinoma.     

The latent gene expression of Epstein-Barr virus in nasopharyngeal carcinoma

AIM: To examine the latent membrane protein 1(LMP1)-DNA sequence in nasopharyngeal carcinoma(NPC) and detect mRNA expression of LMP1,EBNA1,EBNA2,and to explore the relationship between EBV infectious status,expression products and NPC carcinogenesis.METHODS: LMP1 DNA was detected in NPC by PCR.Direct sequence was applied to analyze the difference between NPC-LMP1-DNA and B95-8- LMP1-DNA.mRNA expressions of LMP1,EBNA1,EBNA2 in NPC were detected by nested RT-PCR.RESULTS: LMP1 DNA existed in all 47 NPC tissues.Several single nucleotide variations were found between NPC-LMP1-DNA and B95-8- LMP1-DNA.The notable variation was the lost of XhoⅠrestriction site in NPC.Direct sequence showed 30 bp deletion in NPC.The mRNA expressions of LMP1,EBNA1 and EBNA2 in NPC were 76.6%,80.0% and 74.5% respectively by nested RT-PCR.The expression of EBNA1 in NPC was promoted by Q promoter while the expression of EBNA1 in B95-8 was promoted by C promoter.CONCLUSION: The way of EBV involved in NPC is complex.Latent genes such as LMP1,EBNA1 and EBNA2 as well as early lytic gene BARF1 may all play certain roles in NPC carcinogenesis.     

Growing on the street: Multilevel correlates of street tree growth in Montreal

Tree planting has been favoured in many North American cities, including Montreal which aims to increase its canopy from 20% to 25% in 2025. However, the mortality rate of street trees is especially high in the first few years after planting. Studies have shown that variables that are intrinsic to the tree and those related to its location, the urban form and the socio-demographic characteristics of the surrounding environment are significantly associated either with trees’ survival rate or with vegetation cover. In this research we examine variables that have statistical associations with tree growth, which is the diameter at breast height divided by the number of years on the ground, for approximately 28,000 street trees in Montreal. Independent variables were nested into three spatial scales: the tree (species and physical variables), the street section (urban form variables), and the census tract (socio-demographic variables). Multilevel models reveal that 65.51% of the growth variance is potentially explained by the species and planting physical conditions such as the east and north sides (positive associations with the growth), signage as an obstruction (negative association). 28.54% of the grow variance is potentially explained by the urban form, in our case building age (convex relationship with the growth), mixed zoning (negatively) and residential zoning (positively). At the neighbourhood level, although none of our variables is significant, 6.95% of the growth variance is be potentially explained by other missing variables. New planting programs should hence consider the urban form in order to improve tree growth.     

Differential microRNA expression profile in laryngeal cancer and effect of miR-125a-5p on proliferation of laryngeal cancer cell line

AIM：To investigate the differential microRNA expression profiles between laryngeal cancer and adjacent normal laryngeal mucosa. METHODS：Forty two pairs of laryngeal cancer tissue and adjacent normal laryngeal mucosa tissue were collected. Ten pairs of samples were used for determining microRNA expression by the method of miRNA microarray chip. Data analysis was performed to find out the significant differential microRNA expression profile in laryngeal cancer, and the difference was verified by quantitative real-time PCR (qRT-PCR) analysis on another 32 pairs of samples. Methyl thiazolyl tetrazolium (MTT) assay and colony-forming assay were used to analyze the proliferation of Hep2 cells induced by miR-125a-5p. RESULTS：Both miRNA microarray and qRT-PCR showed that the expression of let-7f-5p, miR-10a-5p, miR-125a-5p, miR-144-3p, miR-195-5p and miR-203 was down-regulated in laryngeal cancer tissues. miR-125a-5p suppressed the proliferation of Hep2 cells. CONCLUSION：The results of microarray are accordant with those of qRT-PCR. Significant difference of miRNA expression profiles between laryngeal cancer and adjacent normal laryngeal mucosa indicates that miRNAs may play a role in carcinogenesis and progression of laryngeal cancer. miR-125a-5p inhibits the proliferation of Hep2 cell, indicating a novel therapeutic target against laryngeal cancer.     

miR-485-5p inhibits viability and migration and invasion abilities of hepatocellular carcinoma Hep3B cells by targeting SOX5

AIM: To investigate the effects of microRNA-485-5p (miR-485-5p) on the viability, migration and invasion abilities of hepatocellular carcinoma cells and the underlying mechanism. METHODS: The expression levels of sex determining region Y-box 5 (SOX5) mRNA and miR-485-5p in the hepatocellular carcinoma Hep3B cells were detected by RT-qPCR with normal hepatocyte THLE-3 as control. Western blot was used to measure the expression levels of SOX5, proliferating cell nuclear antigen (PCNA), Ki67, cyclin D1 and matrix metalloproteinase-2 (MMP-2). The viability of Hep3B cells was measured by MTT assay. The migration and invasion abilities of the Hep3B cells were detected by Transwell assay. Dual-luciferase reporter assay system was applied to verify the relationship between miR-485-5p and SOX5. RESULTS: Compared with the control cells, the expression level of miR-485-5p was decreased in hepatocellular carcinoma cells Hep3B, Huh7 and HCCLM3 (P<0.05), while the expression of SOX5 at mRNA and protein levels were significantly increased (P<0.05). Over-expression of miR-485-5p inhibited the viability, migration and invasion of Hep3B cells. miR-485-5p targeted the 3′-UTR of SOX5 and negatively regulated the expression of SOX5. Knocking-down of SOX5 expression inhibited the viability, migration and invasion of Hep3B cells. Over-expression of SOX5 partially reversed the inhibitory effect of miR-485-5p over-expression on the viability, migration and invasion of Hep3B cells. CONCLUSION: miR-485-5p inhibits the viability, migration and invasion of Hep3B cells by targeting SOX5 gene. miR-485-5p is a potential molecular target for hepatocellular carcinoma.     

Hepatocyte growth factor enhances the neural differentiation from human embryonic stem cells

AIM: To investigate the possibility that hepatocyte growth factor (HGF) directly induces differentiation of human embryonic stem cells (hESCs) into neural progenitors (NPs). METHODS: hESCs colonies were induced to form the embryoid body (EB). Four-day-old EBs were randomly divided into 4 groups: control group (EBs were cultured in neural induction medium); G5 supplement group (EBs were cultured in neural induction medium supplied with G5 supplement); HGF group (EBs were cultured in neural induction medium supplied with 10 mg/L HGF), and HGF+G5 group (EBs were cultured in neural induction medium supplied with 10 mg/L HGF and G5 supplement). After induced in suspension system for 7 days, EBs with various treatments were cultured in poly-D-lysine/laminin-coated plates for 7-10 days for selection of NPs. NPs were gathered by 0.3 g/L dispase treatment and characterized by immunofluorescence staining. The percentages of the nestin+ cells in NPs in various groups were detected by fluorescent activated cell sorter (FACS). The multipotency of NPs was determined by immunofluorescence staining after the NPs were cultured without G5 and HGF for 7 days. The expression of region markers of neural progenitors treated with sonic hedgehog (Shh) protein (one of the neural inductive signals), was detected by RT-PCR. RESULTS: HGF+G5 supplement induced hESCs differentiation into neural progenitors. Immunofluorescence staining indicated that NPs differentiated from hESCs expressed NP markers including nestin, Pax6 and musashi-1. FACS data showed that the proportion of nestin positive cells in HGF+G5 supplement group (87.3%±3.9%) was the highest in all treatment groups. The time of HGF and G5 supplement treatment was important to differentiate into NPs, the maximal effect was observed at 7th day. After treated with Shh, the expression of ventral forebrain/hindbrain marker genes (Nkk2.1, and Nkk2.2) and hindbrain progenitor marker gene Gbx2 in NPs were upregulated, while the forebrain progenitor marker genes Otx2 and Bf1 were downregulated. CONCLUSION: The neural induction system containing HGF and G5 supplement effectively induces the differentiation of hESCs into NPs, which might be a potent model for investigating the mechanism of neural development and differentiation.     

Study on hyper methylation of p15INK4B gene in multiple myeloma

AIM: To study the characteristics and regulations of p15 (MST INK4B) methylation in multiple myeloma (MM). METHODS: Method of methylation-specific PCR was applied in 23 cases of MM about the methylation rate of p15 gene. RESULTS: Methyaltion rate in MM was 73.5%(17/23). The PCR product was a fragment of 148 bp. In four stageⅠcases of MM with plasma cell-typed bone marrow profile, p15^INK4B gene was non-methylated; In one case of stag ⅡMM and one case of stage Ⅲ MM with mature plasma typed bone marrow profile, p15^INK4B gene was no-methylated, too, while in many cases of stageⅠ、stage Ⅱand stage Ⅲ with naive plasma cell in bone marrow profile which were plasma cell-typed or mixed typed, p15^INK4B gene methylation was frequently detected. The methylation rates for stageⅠ、stage Ⅱand stage Ⅲ MM were respectively 55%(5/9),100%(7/7) and 71.4%(5/7). CONCLUSION: p15 gene methylation was a possible pathogenic factor,and might be related to the progression and prognosis of the disease.