Limited knowledge and distrust are important social factors of out-patient' s 'inappropriate diagnosed seeking behaviour': a qualitative research in Shanghai.

AIMS: This study is designed to present out-patient's 'inappropriate diagnosed seeking behaviour' in tertiary hospitals and interpret its association with some potential social factors. METHODS: A qualitative study based on grounded theory was designed in this paper. The participates were recruited by a two-stage process. The field observation and in-depth interview were adopted for data collection. Multi-round (five rounds) sampling and continuing data analysis were adopted as well. RESULTS: Totally 26 out-patients from three tertiary hospitals in Shanghai were involved. Four focused codes, including 'limited policy-related knowledge', 'limited health-related knowledge', 'distrust on related policy' and 'distrust on medical networks', were identified. Then, a theoretical model about the association of out-patient's 'limited knowledge' with 'distrust' and its relationship with 'inappropriate first-diagnosed seeking behaviour' in tertiary hospitals was developed. CONCLUSION: 'Inappropriate first-diagnosed seeking behaviour' of the out-patients in tertiary hospitals is closely associated with their limited knowledge and related distrust. Great effort on improving publics' knowledge and rebuilding a benign trust relationship with out-patients and the medical networks is found to be essential for guiding publics' appropriate first-diagnosed health behaviour in various levels of medical institutions.

Radar Emitter Signal Recognition Based on One-Dimensional Convolutional Neural Network with Attention Mechanism.

As the real electromagnetic environment grows complex and the quantity of radar signals turns massive, traditional methods, which require a large amount of prior knowledge, are time-consuming and ineffective for radar emitter signal recognition. In recent years, convolutional neural network (CNN) has shown its superiority in recognition so that experts have applied it in radar signal recognition. However, in the field of radar emitter signal recognition, the data are usually one-dimensional (1-D), which takes more time and storage space than by using the original two-dimensional CNN model directly. Moreover, the features extracted from convolutional layers are redundant so that the recognition accuracy is low. In order to solve these problems, this paper proposes a novel one-dimensional convolutional neural network with an attention mechanism (CNN-1D-AM) to extract more discriminative features and recognize the radar emitter signals. In this method, features of the given 1-D signal sequences are extracted directly by the 1-D convolutional layers and are weighted in accordance with their importance to recognition by the attention unit. The experiments based on seven different radar emitter signals indicate that the proposed CNN-1D-AM has the advantages of high accuracy and superior performance in radar emitter signal recognition.

CircRNA hsa-circ-0014359 promotes glioma progression by regulating miR-153/PI3K signaling.

RNA back splicing produces circRNA, a new type of non-coding RNA. Studies have indicated that circRNAs play important roles in malignant tumors of the central nervous system. Here, we aimed to evaluate the expression of the circRNA, hsa-circ-0014359 (circ-0014359) in human glioma cell lines to assess its function in glioma progression and prognosis. The expression of circ-0014359 was increased in T98G and SHG44 cancer cell lines and glioma tissues from patients, when compared with control cells and tissue. SiRNA-mediated silencing of circ-0014359 potently inhibited cell viability, migration, invasion, and apoptosis of glioma cells. Further, our observations indicated that circ-0014359 acted as a miRNA-153 (miR-153) sponge in glioma cells. Transfection of miR-153 inhibitor significantly suppressed si-circ-0014359-induced inhibition of cell viability, cell migration, and invasion. The increased expression of circ-0014359 levels in glioma cells was correlated with downregulated expression of miR-153. Overexpression of miR-153 reduced p-AKTser473 (a PI3K pathway indicator) and the rescue experiment showed enhanced p-AKTser473 expression. Together, our study suggests that circ-0014359 promotes glioma progression via targeting miR-153/PI3K signaling pathway. Thus, our study provides insights into glioma progression and reveals potential new targets for treatment of glioma.

Cytotropic heterogeneous molecular lipids inhibit the growth of glioma cells by inducing apoptosis and autophagy.

The cytotropic heterogeneous molecular lipid (CHML) is a mixture of lipids isolated from natural products. CHML is an effective therapy for various kinds of cancers; however, the effect of CHML on glioma cells was seldom reported. Here, we aim to explore the cytotoxicity of CHML on glioma cells, and analyze the possible mechanisms. U251 glioma cells were cultured with CHML at different concentration, and the growth inhibition was measured by CCK-8 assay. Induced apoptosis were detected by flow cytometry, and the induced autophagies were observed by a transmission electron microscope. The key molecules involved in apoptosis and autophagy were detected by quantitative PCR and western-blot. CHML might inhibit the growth of U251 cells and promote apoptosis by up-regulating the expressions of Caspase-8 and Caspase-3; CHML also induced autophagy of U251 cells by promoting the expressions of MAP LC-3 and Beclin-1. CHML can inhibit proliferation of U251 cells by promoting cell apoptosis and inducing autophagy.

The application of improved abdominal wall punctures technique in ventriculoperitoneal shunt for hydrocephalus: a retrospective analysis versus open mini-laparotomy.

PURPOSE: Ventriculoperitoneal shunt (VPS) remains as one of the main treatment for hydrocephalus. The traditional technique for placing the distal ends of shunts is via a mini-laparotomy. However, laparotomies are relatively time consuming. Trocars to penetrate abdominal wall by blind puncture have been used. Here, we report on the abdominal wall puncture technique, and compare the possible complications and outcomes with traditional mini-laparotomy. MATERIALS AND METHODS: We use a 5mm incision at the inverse McBurney point. The abdominal wall on both sides of the incision point is lifted with two towel clips prior to puncture to create a potential gap between the abdominal wall and viscera. After the puncture, a guide wire is inserted followed by a dilator, introducer and the distal shunt tubing using a Seldinger technique. In this process, the operator feels resistance give with breakthrough of parietal peritoneal. After the insertion of introducer, a negative pressure injection test helps confirm whether the introducer is inside the peritoneum. RESULTS: Operative time is less than with mini-laparotomies. Postoperative abdominal symptoms are mild. Out of 29 patients there were no puncture related complications. CONCLUSION: The improved abdominal-wall puncture technique is a simple, fast, economical and effective method. Patients, who are treated by the method, generally experience rapid postoperative recoveries.

Effects of transforming growth factor-ß inhibitor on the proliferation of glioma stem/progenitor cell.

Transforming growth factor-ß (TGF-ß) signaling pathways play an important role in inhibition and promotion of cell proliferation in neural stem cells (NSCs) and glioma stem/progenitor cells (GSPCs), respectively. However, the mechanisms underlying these processes remain unknown. We presumed that there may be functional inhibition at the receptor downstream of TGF-ß signaling pathway leading to the activation of non- TGF-ß/Smad signaling pathway, which stimulates the proliferation of GSPCs. In this study, GSPCs, from glioma cell lines SHG44, were cultivated with TGF-ß receptor inhibitors (LY2157299 and LY2109761), and then the proliferative capability of GSPCs was measured; as well, the synthesis of TGF-ß ligands, and the mRNA expression level of TGF-ß and some key molecules of non-Smad signaling pathways were also detected. Our results showed that inhibitors against TGF-ß receptors could promote the proliferation of GSPCs, and the synthesis of TGF-ß ligands was enhanced. Furthermore, the inhibition of TGF-ß receptor may lead to the activation of non-Smad signaling pathways (mTOR and NF-κB). In conclusion, the down-regulation of TGF-ß receptor capability by TGF-ß receptor inhibitors can increase TGF-ß ligands synthesis and secretion, which then promote GSPCs proliferation by activating non-Smad signaling pathways.

[Efficacy analysis of endoscopic endonasal transsphenoidal surgery for recurrent or regrowing pituitary adenomas].

OBJECTIVE: To analyze the safety and efficacy of surgical removal of recurrent or regrowing pituitary adenomas by endoscopic endonasal transsphenoidal approach. METHODS: The clinical data were retrospectively reviewed for 28 patients undergoing endoscopic endonasal transsphenoidal surgery for recurrent or regrowing pituitary adenomas between April 2010 and December 2013. There were 9 males and 19 females with a mean age of 44. 2 (11 - 73) years. The maximal tumor diameter ranged from 2. 1 to 6.9 cm. The Knosp grades were 1 -2 (n = 11), 3 (n =8) and 4 (n =9). Fifteen tumors were endocrinically functional and the remainder endocrinically nonfunctional. All operations were performed with an assistance of intraoperative neuronavigation. Neuro-ophthalmological, neuroimaging and endocrinological results were followed up postoperatively. And surgical outcomes and risk factors were analyzed for incomplete tumor resection in previous operations. RESULTS: The mean follow-up period was 19. 1 (3 - 45) months. Gross total resection(n = 18, 64. 3%), subtotal resection(n = 6, 21. 4%) and partial resection(n = 4, 14. 3%) were achieved. Postoperatively, visual acuity improved in 11 patients (73. 3%) and 6 patients (40. 0%) showed endocrine remission. Qne patient had short-term postoperative leakage of cerebrospinal fluid (CSF). CONCLUSION: Endoscopic endonasal transsphenoidal surgery is both safe and effective for recurrent or regrowing pituitary adenomas.

The establish of the HPLC method to examine the plasma concentration of lamotrigine and oxcarbazepine.

To establish the HPLC method to examine plasma concentration of lamotrigine and oxcarbazepine. This study set chlorzoxazone as the internal standard, chromatographic column was Column C18 (200×4.6mm, 5um) of DIKMA company, the mobile phase was methanol, water and trifluoroacetic acid, with rate of 40: 60: 0.0005, at a flow rate of 1 mllmin(-1), the detected wavelength was 240 nm. The plasma concentrations of lamotrigine was 0.5-50ug•mL(-1), the standard curve was excellent for Y=0.5511C-0.5669, r=0.9940, average recovery was 91.40%; The plasma concentrations of oxcarbazepine was 0.5-50ugmL-1, the standard curve was good for Y=0.4026C-0.5895, r=0.9925, and the average recovery was 89.59%; The three plasma concentrations of lamotrigine were respectively 25µg•mL(-1), 10 µg•mL(-1) and 2µg•mL(-1) and its five parallel sample for injection RSD were respectively 4.01%, 6.15% and 4.64%; The three plasma concentration of oxcarbazepine were 25µg•mL(-1)-1(-1), 10µg•mL(-1)-1(-1) and 2µg•mL(-1)-1(-1), and its five parallel sample for injection RSD were respectively 3.05%, 4.27% and 9.01%. This method was easy to operate, high recovery and high precision, and was applicable to the clinical detection for plasma concentration of lamotrigine and oxcarbazepine.

Analysis of factors influencing fall risk among elderly people in rural of China.

Falls can cause serious health problems in the elderly. China is gradually entering a moderately aging society. In rural areas of China, the elderly are at a higher risk of falling. This study aims to explore and analyze the factors affecting the fall risk of elderly people in rural areas of China, and provide theoretical basis for reducing the fall risk of elderly people. M County, Anhui Province, China was selected as the survey site by the typical field sampling method, and the elderly people in rural areas were selected as the research objects. A total of 1187 people were investigated. Mann-Whitney U test and Kruskal-Wallis H test were used for univariate analysis, and multiple linear regression was used for multivariate analysis. Chronic diseases, multimorbidity, daily living ability, mental health, working status and family doctors are the factors that influence falls among elderly people in rural areas of China (P < 0.05, Adjusted R2 = 0.395). The falls risk of the elderly in rural areas of China is influenced by multiple factors. Therefore, comprehensive measures should be taken to reduce the fall risk by comprehensively evaluating the influencing factors.

Effect of all-trans retinoic acid on the differentiation of U87 glioma stem/progenitor cells.

GSPCs (glioma stem/progenitor cells) were isolated from U87 glioma cell lines by serum-free neural stem cell medium. Four concentrations (1, 2, 4, and 8 µmol/L) of ATRA (all-trans retinoic acid) were used to induce the differentiation of GSPCs in the medium with or without growth factors. The effect of ATRA on the differentiation of GSPCs was analyzed by flow cytometry, real-time-PCR, and immunofluorescence. The differentiation of GSPCs could be induced by 1 or 2 µmol/L ATRA when GSPCs were cultured in growth factor-free medium. The detection of real-time-PCR showed that the level of GFAP (glial fibrillary acidic protein) mRNA of differentiated GSPCs in the growth factor-free medium containing 1 µmol/L ATRA group was significantly higher than that in the control group, and there was no significant difference in the level of TUBB-3 mRNA between the two groups. The GSPCs suffered apoptosis in the growth factor-free medium containing 4 or 8 µmol/L ATRA. The differentiation of GSPCs could not be induced by ATRA when GSPCs were cultured in the medium containing growth factors. The percentage of cells in G0/G1 phase was 84.26 ± 2.24 %, and the percentage of apoptosis was 18.95 ± 2.53 % in experimental groups which was similar to those in the control group. In conclusion, ATRA has certain capacity to induce differentiation of GSPCs, while its effective concentration should be controlled strictly. The differentiation of GSPCs induced by ATRA cannot antagonize the formidable differential inhibition of epidermal growth factor and basic fibroblast growth factor.

[Host glial cell canceration induced by glioma stem cells in GFP/RFP dual fluorescence orthotopic glioma models in nude mice].

OBJECTIVE: During the process of tissue remodeling in human tumor transplantation models, the roles of the inoculated tumor cells and host tissue in tumor progression is still largely unknown. The aim of this study was to investigate the relationships and interactions between these two sides using GFP-RFP double fluorescence tracing technique. METHODS: Red fluorescence protein (RFP) gene was stably transfected into glioma stem cell line SU3, then SU3-RFP cells were transplanted into the brain of athymic nude mice with green fluorescence protein (GFP) expression. After the intracerebral tumors were formed, the relationship and interaction between GFP cells and RFP cells were analyzed. Highly proliferative GFP cells were screened out, and monocloned with micro-pipetting. DNA content assay, chromosome banding and carcinogenicity test of the GFP cells were performed to observe the GFP cells' cancerous phenotype in nude mice. RESULTS: In the transplantable tumor tissue, besides a great quantity of RFP cells, there were still a proportion of GFP cells and GFP/RFP fusion cells. The proportion of RFP cells, GFP cells and GFP/RFP cells were (88.99 ± 1.46)%, (5.59 ± 1.00)%, and (4.11 ± 1.020)%, respectively. Two monoclonal host GFP cells (H1 and H9) were cloned, which demonstrated the properties of immortality, loss of contact inhibition, and ultra-tetraploid when cultured in vitro. Both H1 and H9 cells expressed CNP, a specific marker of oligodendrocytes. The GFP cells also demonstrated 100% tumorigenic rate and high invasive properties in vivo. CONCLUSIONS: In this glioma transplantation model, the transplanted tumor tissues contained not only transplanted glioma stem cells but also cancerous host GFP cells. Our findings offer important clues to further research on the relationships among different members in the tumor microenvironment.

A hydrogel-based first-aid tissue adhesive with effective hemostasis and anti-bacteria for trauma emergency management.

BACKGROUND: Clinical tissue adhesives remain some critical drawbacks for managing emergency injuries, such as inadequate adhesive strength and insufficient anti-infection ability. Herein, a novel, self-healing, and antibacterial carboxymethyl chitosan/polyaldehyde dextran (CMCS/PD) hydrogel is designed as the first-aid tissue adhesive for effective trauma emergency management. METHODS: We examined the gel-forming time, porosity, self-healing, antibacterial properties, cytotoxicity, adhesive strength, and hemocompatibility. Liver hemorrhage, tail severance, and skin wound infection models of rats are constructed in vivo, respectively. RESULTS: Results demonstrate that the CMCS/PD hydrogel has the rapid gel-forming (~ 5 s), good self-healing, and effective antibacterial abilities, and could adhere to tissue firmly (adhesive strength of ~ 10 kPa and burst pressure of 327.5 mmHg) with excellent hemocompatibility and cytocompatibility. This suggests the great prospect of CMCS/PD hydrogel in acting as a first-aid tissue adhesive for trauma emergency management. The CMCS/PD hydrogel is observed to not only achieve rapid hemostasis for curing liver hemorrhage and tail severance in comparison to commercial hemostatic gel (Surgiflo ®) but also exhibit superior anti-infection for treating acute skin trauma compared with clinical disinfectant gel (Prontosan ®). CONCLUSIONS: Overall, the CMCS/PD hydrogel offers a promising candidate for first-aid tissue adhesives to manage the trauma emergency. Because of the rapid gel-forming time, it could also be applied as a liquid first-aid bandage for mini-invasive surgical treatment.

Factors related to self-rated health of older adults in rural China: A study based on decision tree and logistic regression model.

Objective: This study aimed to explore the related factors of self-rated health (SRH) by using decision tree and logistic regression models among older adults in rural China. Methods: Convenience sampling was employed with 1,223 enrolled respondents who met the inclusion criteria from 10 randomly selected villages in M County in China. The content of the questionnaire covered demographic characteristics, physical and mental health, sleep status, and risk of falling. The Pittsburgh Sleep Quality Index (PSQI) and the Morse Falls Risk Scale (MFS) were used to evaluate sleep status and risk of falling, respectively. The decision tree and logistic regression models were employed to analyze the related factors of SRH. Results: Notably, 817 (68.7%) subjects had good SRH. The logistic regression model showed that living standard, alcohol consumption, sleep quality, labor, hospitalization, discomfort, the number of chronic diseases, and mental health were associated with SRH (P-value < 0.05), while the decision tree model showed that the number of chronic diseases, sleep quality, mental health, hospitalization, gender, and drinking were associated with SRH. The sensitivity and specificity of the logistic regression model were 67.7 and 75.5%, respectively, and the area under the ROC curve was 0.789 (0.763, 0.816); the sensitivity and specificity of the decision tree model were 71.5, and 61.4% respectively, and the area under the ROC curve was 0.733 (0.703, 0.763). Conclusion: Decision tree and logistic regression models complement each other and can describe the factors related to the SRH of the elderly in rural China from different aspects. Our findings indicated that mental health, hospitalization, drinking, and sleep quality were the important associated factors.

Gycyrrhizic acid alleviates atherosclerotic lesions in rats with diabetes mellitus.

Gycyrrhizic acid (GA), an inhibitor of high mobility group box 1 (HMGB1), inhibits inflammatory responses and is involved in the occurrence and development of several inflammation­related diseases. However, the role of GA in the atherosclerotic lesions caused by diabetes mellitus (DM) remains unknown. In the present study, Sprague Dawley rats were selected to desi=gn a diabetic atherosclerosis (AS) model. Rats from the DM­AS group were subsequently divided into DM­AS, DM­AS + GA (50 mg/kg) and DM­AS + GA (150 mg/kg) groups. Biochemical analyzers were used to measure levels of blood glucose, fasting insulin, total cholesterol, total triglyceride, low­density lipoprotein and high­density lipoprotein. The number of plaques was recorded after collection of thoracic aortas from the rats. The intimal thickness of arterial tissue was detected by hematoxylin and eosin staining. The expression levels of CD68 and α­smooth muscle actin (α­SMA) were detected by immunohistochemistry. The expression of tumor necrosis factor­α, interleukin (IL)­6 and IL­1ß in the serum of the rats was detected by ELISA. The expression of fatty acid synthetase, sterol regulatory element binding protein 1C, HMGB1 and receptor for advanced glycation end products (RAGE) was detected by western blotting. Reverse transcription quantitative PCR was used to detect the mRNA expression of HMGB1 and RAGE. The results demonstrated that GA treatment could decrease the body weight, blood glucose level and biochemical parameters of AS DM rats in a dose­dependent manner. In addition, GA decreased the intimal thickness of carotid artery and the formation of plaque in rats with diabetic AS. Furthermore, GA inhibited macrophage activation and decreased α­SMA expression in vascular smooth muscle cells, and decreased the expression of proteins (FAS and SREBP­1c) and inflammatory factors. Taken together, the findings from the present study demonstrated that GA may have a therapeutic effect on DM­associated AS. This study provides a theoretical basis for the treatment of diabetic AS.

Synergistic antitumor effect of ING4/PTEN double tumor suppressors mediated by adenovirus modified with arginine-glycine-aspartate on glioma.

BACKGROUND: Gene therapy is regarded as a new and promising therapeutic modality for cancers, and adenovirus is one of the most frequently used vectors. However, because of low or absent coxsackievirus and adenovirus receptor levels on the surface of many kinds of tumor cells, the efficiency of adenovirus infection of target tumor cells may be low. Meanwhile, gene therapy by a single vector carrying two or more antioncogenes can improve treatment effects and reduce side effects from vectors. In this research, we aimed to detect the antitumor effect of ING4/PTEN double tumor suppressors mediated by adenovirus modified with arginine(R)-glycine(G)-aspartate(D) (RGD) on glioma cells. METHODS: We treated U87 glioma cells with PBS, blank adenovirus or adenovirus carrying RGD, ING4, PTEN, or both ING4 and PTEN, then we detected and compared the U87 cells' growth, apoptosis, and invasion. Moreover, we established a U87 glioma transplantation tumor model to study the antitumor effect in vivo by measuring the volume and weight of tumor masses in each condition. In addition, we analyzed the transcription of related genes by fluorescent quantitative PCR and detected their expression by immunohistochemistry staining to reveal the underlying mechanisms. RESULTS: The double tumor suppressors ING4/PTEN could inhibit the growth of U87 glioma cells with a synergistic antitumor effect, and the RGD modification also acted as an antioncogene to inhibit U87 cell invasion and tumor angiogenesis. CONCLUSIONS: The ING4/PTEN double tumor suppressors mediated by adenovirus modified with RGD had a significantly synergistic antitumor effect on glioma.

Identification of Exogenous Nitric Oxide-Responsive miRNAs from Alfalfa (Medicago sativa L.) under Drought Stress by High-Throughput Sequencing.

Alfalfa (Medicago sativa L.) is a high quality leguminous forage. Drought stress is one of the main factors that restrict the development of the alfalfa industry. High-throughput sequencing was used to analyze the microRNA (miRNA) profiles of alfalfa plants treated with CK (normal water), PEG (polyethylene glycol-6000; drought stress), and PEG + SNP (sodium nitroprusside; nitric oxide (NO) sprayed externally under drought stress). We identified 90 known miRNAs belonging to 46 families and predicted 177 new miRNAs. Real-time quantitative fluorescent PCR (qRT-PCR) was used to validate high-throughput expression analysis data. A total of 32 (14 known miRNAs and 18 new miRNAs) and 55 (24 known miRNAs and 31 new miRNAs) differentially expressed miRNAs were identified in PEG and PEG + SNP samples. This suggested that exogenous NO can induce more new miRNAs. The differentially expressed miRNA maturation sequences in the two treatment groups were targeted by 86 and 157 potential target genes, separately. The function of target genes was annotated by gene ontology (GO) enrichment and kyoto encyclopedia of genes and genomes (KEGG) analysis. The expression profiles of nine selected miRNAs and their target genes verified that their expression patterns were opposite. This study has documented that analysis of miRNA under PEG and PEG + SNP conditions provides important insights into the improvement of drought resistance of alfalfa by exogenous NO at the molecular level. This has important scientific value and practical significance for the improvement of plant drought resistance by exogenous NO.

[The rules of acupoint selection of acupuncture for dry eye].

The rules of acupoint selection of acupuncture for dry eye in recent 10 years were summarized to provide reference for clinical treatment. The clinical researches regarding acupuncture for dry eye published from May 5, 2007 to December 1, 2017 were searched in CNKI, WANFANG and VIP database. The acupoint and meridian used and application frequency were analyzed to summarize the rules of acupoint selection. Totally, 52 related clinical papers were collected, involving 60 acupoints, 14 meridians and 5 extra point. The total frequency of acupoints was 541, which were mainly related with the bladder meridian, stomach meridian and gallbladder meridian. In conclusion, the rules of acupoint selection of acupuncture for dry eye highlighted meridians circulation, acupoint combination, and syndrome differentiation.

Glioma stem cells are more aggressive in recurrent tumors with malignant progression than in the primary tumor, and both can be maintained long-term in vitro.

BACKGROUND: Despite the advances made during decades of research, the mechanisms by which glioma is initiated and established remain elusive. The discovery of glioma stem cells (GSCs) may help to elucidate the processes of gliomagenesis with respect to their phenotype, differentiation and tumorigenic capacity during initiation and progression. Research on GSCs is still in its infancy, so no definitive conclusions about their role can yet be drawn. To understand the biology of GSCs fully, it is highly desirable to establish permanent and biologically stable GSC lines. METHODS: In the current study, GSCs were isolated from surgical specimens of primary and recurrent glioma in a patient whose malignancy had progressed during the previous six months. The GSCs were cryopreserved and resuscitated periodically during long-term maintenance to establish glioma stem/progenitor cell (GSPC) lines, which were characterized by immunofluorescence, flow cytometry and transmission electronic microscopy. The primary and recurrent GSPC lines were also compared in terms of in vivo tumorigenicity and invasiveness. Molecular genetic differences between the two lines were identified by array-based comparative genomic hybridization and further validated by real-time PCR. RESULTS: Two GSPC lines, SU-1 (primary) and SU-2 (recurrent), were maintained in vitro for more than 44 months and 38 months respectively. Generally, the potentials for proliferation, self-renewal and multi-differentiation remained relatively stable even after a prolonged series of alternating episodes of cryopreservation and resuscitation. Intracranial transplantation of SU-1 cells produced relatively less invasive tumor mass in athymic nude mice, while SU-2 cells led to much more diffuse and aggressive lesions strikingly recapitulated their original tumors. Neither SU-1 nor SU-2 cells reached the terminal differentiation stage under conditions that would induce terminal differentiation in neural stem cells. The differentiation of most of the tumor cells seemed to be blocked at the progenitor cell phase: most of them expressed nestin but only a few co-expressed differentiation markers. Transmission electron microscopy showed that GSCs were at a primitive stage of differentiation with low autophagic activity. Array-based comparative genomic hybridization revealed genetic alterations common to both SU-1 and SU-2, including amplification of the oncogene EGFR and deletion of the tumor suppressor PTEN, while some genetic alterations such as amplification of MTA1 (metastasis associated gene 1) only occurred in SU-2. CONCLUSION: The GSPC lines SU-1 and SU-2 faithfully retained the characteristics of their original tumors and provide a reliable resource for investigating the mechanisms of formation and recurrence of human gliomas with progressive malignancy. Such investigations may eventually have major impacts on the understanding and treatment of gliomas.

Ultrastructural studies of glioma stem cells/progenitor cells.

Although the ultrastructural features of several brain tumor cells have been studied in details, the ultrastructure of glioma stem cells/progenitors cells (GSPC) has rarely been reported. In this paper, the authors describe the ultrastructural features of GSPCs isolated from both a glioma tissue and the human glioma cell SHG-44 cell line. The ultrastructural features of the two kinds of GSPCs were similar, with relatively developed mitochondria, Golgi apparatuses, ribosomes, undeveloped rough endoplasmic reticula, seldom lysosomes and no typical autophagosomes, and high nuclear-cytoplasmic ratio. Their nuclei, frequently containing huge amounts of euchromatin and a small quantity of heterochromatin, were mostly globular; and the majority of the nuclei had only one nucleole. Typical apoptotic cells could hardly be found in tumor spheres, and between adjacent cells there were cell junctions, which probably were incompletely developed desmosomes or intermediate junctions. In conclusion, their ultrastructural features showed that GSPCs were at the primary stage of differentiation, and could even partially reveal the underlying reasons for the malignant proliferation and differential inhibition of GSPCs.

[Ultrastructural analysis of glioma stem cells-progenitors].

OBJECTIVE: It is well known that glioma stem cells-progenitors (GSCP) proliferate indefinitely and hardly differentiate in vitro, however, the reasons remain unknown. The aim of this study was to explore the ultrastructural basis of GSCP. METHODS: GSCP, kept by our laboratory, were collected, embedded, and cut into ultrathin sections and observed under the transmission electron microscope. RESULTS: A single GSCP usually had relatively well developed mitochondria, Golgi apparatuses, ribosomes, and undeveloped rough endoplasmic reticulum, but seldom lysosomes and no typical autophagosomes were found, and the nuclear-cytoplasmic ratio was high. The nuclei frequently contained huge amounts of euchromatin and a small quantity of heterochromatin, and in most nuclei there were only one nucleolus, however, two or more nucleoli were also common. Typical apoptotic cells could hardly be found in tumor-spheres, and between neighboring cells in tumor-spheres there were incompletely developed desmosomes or intermediate junction. CONCLUSION: The ultrastructural features of glioma stem cells-progenitors showed that BTSCP were very primitive and the lack of autophagy and the underdevelopment of some other cellular organelles are probably the reasons for the differential inhibition of GSCPs.