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Bi1-xMgxFeO3 (BMFO, x = 0, 0.02, 0.04, 0.06 and 0.08) multiferroic films were directly synthesized on flexible stainless steel (FSS), save the bottom electrode process, by means of sol&ndash, gel spin-coating technology. The effects of different bending conditions on ferroelectric, dielectric and leakage-current properties of BMFO films were investigated. The leakage-current densities of BiFeO3 (BFO, x = 0) and BMFO (x = 0.06) films were 5.86 &times, 10&minus, 4 and 3.73 &times, 7 A/cm2, which shows that the BMFO (x = 0.06) has more than three orders of magnitude lower than that of BFO film. The residual polarization (2 Pr) can be enhanced from 120 to 140 &mu, C/cm2. The proper doping of Mg in BiFeO3 film could provide an effective method for reducing the leakage-current values as well as boosting the ferroelectric properties. In this study, the leakage-current mechanism of low electric field and high electric field of BMFO film is analyzed and established. In addition, the flexible BMFO film maintains practical ferroelectric and leakage-current properties at retention time of 106 s under different symmetry bending conditions. These results indicate that the BFMO film will be very practical in opto-electronic and storage device applications.

Obstructive sleep apnea-hypopnea syndrome (OSAHS), a high incidence, potentially dangerous sleep-disordered breathing disorder, which with the important pathophysiological mechanism of chronic intermittent hypoxia (CIH) in patients. Hypoxia inducible factor -1 alpha (HIF-1α), as an important transcription factor in the development of hypoxia, HIF-1α activation encodes transcription of vascular endothelial growth factor (VEGF) and erythropoietin (EPO) genes. We selected 50 patients with OSAHS, divided them into 23 patients with OSAHS combined with cardiovascular diseases, 27 patients with simple OSAHS and 25 normal subjects. The three groups were monitored by polysomnography. Enzyme linked immunosorbent assay (ELISA) was used to determine the levels of HIF-1α, VEGF and EPO in plasma of 22:00 at bedtime, 2:00 in the nighttime and 7:00 at next morning. It was found that the levels of plasma HIF-1α, VEGF and EPO in the patients with OSAHS combined with cardiovascular disease and simple OSAHS group were higher than that of the normal control group. In OSAHS combined cardiovascular disease group, the levels of HIF-1α and VEGF increased significantly at night and decreased in the morning, but higher than before sleep. The HIF-lα and VEGF levels were negatively correlated with the nocturnal minimum oxygen saturation. It prompted that CIH might increase the expression of VEGF and EPO via HIF-lα. EPO was involved in the pathophysiological processes such as anti-hypoxia and promoting angiogenesis. This effect was relieved by transient hypoxic damage during sleep. If VEGF continued to increase in excess, it might lead to abnormal angiogenesis and increased vascular permeability, which might be an important factor in the cardiovascular complications of OSAHS.

To investigate the use of multi-parameter spectral computed tomography (CT) for the evaluation of rat C6 glioma, 15 male Wistar rats were seeded with C6 glioma cells into the right basal ganglia and scanned 12 days later using spectral CT. Brain sections corresponding to scanned regions were immunostained for proliferation marker protein Ki67 (Ki67). Pearson's correlation coefficients between spectral CT parameters and Ki67 expression were determined. Thirteen rats survived 12 days and developed tumors. Optimal contrast-to-noise ratio achieved was 65 keV. Brain regions containing liquefactive necrosis, solid tumor, peripheral tumor and normal tissue differed significantly with regard to the spectral curve slope (0.24±0.46, 1.81±1.09, 0.8±0.43 and 0.11±0.27, respectively; P

Purpose: To formulate trimethyl chitosan-functionalized retinoic acid-encapsulated solid lipid nanoparticles for the effective treatment of glioma. Methods: Retinoic acid-loaded solid lipid nanoparticles (R-SLNs) were prepared using homogenization followed by sonication. R-SLN surfaces were functionalized electrostatically with trimethyl chitosan as a nanocarrier (TR-SLNs) with enhanced anti-cancer activity. They were evaluated by dynamic light scattering (DLS), scanning electron microscopy, in vitro drug release, and cell cytotoxicity and apoptosis studies. Results: Morphological images showed spherical and uniformly dispersed nanoparticles. A sustained monophasic release pattern was observed throughout the study period. Furthermore, the anti-cancer effect of TR-SLNs was demonstrated by increased cell killing activity compared with the free drug ( p < 0.01); negligible cytotoxicity was observed with blank carriers. Apoptosis assay showed increased cell populations in early/late apoptotic and necrotic phases. Conclusion: This study showed the potential application of surface-modified solid lipid nanoparticles for the effective treatment of brain cancer. Keywords: Lipid nanoparticles, Trimethyl chitosan, Retinoic acid, Glioma, Anti-cancer, Cytotoxicity, Apoptosis

Elimination gasoline vapor in oil tank by mechanical ventilation has disadvantages of long vent time poor safety, and low efficiency, however, those shortcomings can be better conquered if combusted gas is used in the process of the mechanical ventilation. Based on former studies, the research on the effects of inlet location on gasoline vapor’s inert replacement in oil tank by combusted inert gas is studied experimentally in this paper. The conclusions in this paper can provide some useful guidance for the field project of gasoline vapor’s inert replacement in oil tank.

Subtractive hybridization was used to isolate genes expressed uniquely in the immortalized human breast epithelial cell (HBEC) line MCF-10F and not in the mortal HBEC line S-130, from which MCF-10F cells were derived. We identified a 233-bp cDNA that was expressed in MCF-10F cells and not in their mortal counterpart S-130 cells. Sequence comparison with the GenBank database revealed that the cDNA was identical to the gene encoding human ferritin heavy H chain. Northern blot analysis using the isolated cDNA as a probe showed a differentially expressed 1.1-kb transcript of ferritin H in total RNA from the immortal MCF-10F cells, MCF-10F cells treated with the chemical carcinogens 7,12-dimethylbenz[a]anthracene and benzo[a]pyrene, and the breast cancer cell lines MCF-7, HBL-100, T-47D, and BT-20. No ferritin H transcript was detected in the mortal line S-130 or in other primary HBEC cultures. Increased levels of mRNA transcript signals were also detected in total RNA from breast cancer tissue samples. Tissue with ductal hyperplasia had higher expression levels than normal adjacent mammary tissue. In situ hybridization showed high levels of ferritin H transcript in mammary tissue areas with ductal hyperplasia, carcinoma in situ, and infiltrating ductal carcinoma. This is the first report of the differential expression and upregulation of human ferritin H chain gene in immortal HBECs. It may be an important factor in the process of immortalization, possibly an early stage of malignant transformation of HBECs, providing cells with iron necessary for growth and clonal expansion. Also, ferritin iron, once released, may increase the level of reactive iron, leading to an increase in oxygen free-radical generation, oxidative DNA damage, and mutation. Mol. Carcinog. 20:332–339, 1997. © 1997 Wiley-Liss, Inc.

In the present study we have examined the effect of dexamethasone on ob gene mRNA expression and leptin release from isolated human subcutaneous adipocytes. Dexamethasone stimulated leptin release from cultured adipocytes in a time- and dose-dependent manner. A two-fold increase in leptin release was detectable by 36 h of treatment with 10(-7) M dexamethasone. Leptin release was preceded by a significant 83 +/- 30% increase in ob mRNA after 24 h exposure to the compound. Co-incubation of cells with dexamethasone (10(-7) M) and insulin (10(-7) or 10(-9) M) completely blocked the dexamethasone-stimulated increase in ob mRNA and leptin release. These data demonstrate that insulin and glucocorticoids regulate leptin synthesis and release from human adipocytes in vitro.

In order to determine what is the role of genomic alterations in neoplasia, it is necessary to verify what is their function at each one of the various stages of breast cancer progression, which initiates as ductal hyperplasia, progressing to atypical ductal hyperplasia, carcinoma in situ, and invasive and metastatic adenocarcinoma. These studies are hindered by the fact that these stages are not always present in a single patient, or in a sequential manner, or when present the available material might be insufficient or inadequate for performing genetic manipulation for testing their functional role. These disadvantages have been overcome by utilizing an in vitro model of cell transformation, the spontaneously immortalized human breast epithelial cell line (HBEC) MCF- 10F, which upon treatment with the chemical carcinogens benzo(a)pyrene (BP) or 7,12-dimethyl-benz(a)anthracene (DMBA) expresses in a sequential fashion all the phenotypes indicative of neoplastic transformation, i.e., increased survival in agar, formation of colonies in agar methocel, invasiveness in a matrigel in vitro system, and tumorigenesis in severe combined immunodeficient (SCID) mice. The immortalization of MCF-1 OF cells is associated with the presence of a point mutation in exon 7 of the tumor suppressor gene p53. Carcinogen-induced transformation was manifested as colony formation in agar methocel and anchorage independence, which were associated with loss of heterozygosity (LOH) and point mutations in codons 12 and 61 of c-Ha-ras gene. Other oncogenes involved in this early stage were c-neu, c-myc, and int-2. The expression of the tumorigenic phenotype was associated with LOH in the telomeric portion of chromosome 17 and overexpression of the mdm2 gene. This in vitro system provides all of the sequential steps to neoplastic transformation in a reproducible manner, thus providing a paradigm for clarifying the role of the genetic alterations in tumor initiation and progression. © 1995 Wiley-Liss, Inc.

The purpose of this study was to investigate the clinical value of plasma thrombomodulin (PTM) in different diseases or in different severity or complications of diseases, PTM in 979 patients and 60 healthy controls was determined by ELISA method. The results showed that the PTM level in the control group was 20.40 +/- 7.72 microg/L, there was no difference in sex and ages. In chronic primary glomerular disease, the PTM level in chronic renal failure (CRF) group was higher than that in non-CRF group (P0.01). PTM level70 microg/L was defined as its positive criterion. The sensitivity, specificity and positive predictive value in PTM were 85.7%, 82.4% and 77.8% respectively. The PTM level in septemia group was higher than that in non-septemia group (P0.01), the sensitivity, specificity and positive predictive value were 86.6%, 89.5% and 76.5% respectively (50 microg/L as its positive criterion). With respect of multiple trauma, the PTM level in multiple organ failare (MOF) group was higher than that in non-MOF group (P0.01), while the sensitivity, specificity and positive predictive value were 77.8%, 77.3% and 73.7% respectively (40 microg/L as its positive criterion). For systemic lupus erythematosus (SLE), the PTM level in the patients with albuminuria was higher than that in the patients without albuminuria (P0.01), and the sensitivity, specificity and positive predictive value were 77.8%, 92.3% and 93.3% respectively (35.54 microg/L as its positive criterion). For diabetes, the PTM level in complication group was higher than that in group without complications, the sensitivity, specificity and positive predictive value were 53.4%, 97.1% and 98.6% respectively (35.54 microg/L as its positive criterion). The PTM level in microangiopathy group was higher than that in macroangiopathy group (P0.01). The sensitivity, specificity and positive predictive value were 71.2%, 97.1% and 97.9% respectively. Acute leukemia (AL) and multiple myeloma (MM) had higher PTM level and PTM level was extremely high when renal failure developed (P0.01). As compared the acute stage with the restoration stage in stroke, pre-chemotherapeutics with post-chemotherapeutics in AL and MM, and pre-operation with post-operation in cancer, the PTM level was connected with clinical development. The PTM level in the patients with microangiopathy was higher than that in the patients with macroangiopathy (P0.01). The defined PTM level was higher than its normal upper limit as PTM positive criterion in microangiopathy diseases, the sensitivity, specificity and positive predictive value were 77.7%, 71.2% and 75.6% respectively. It is concluded that PTM level is a good criterion in evaluating the microangiopathy, and PTM is also a valuable indicator in prediction or assessment of the severity of diseases, or evaluation of therapeutic effectiveness.

The understanding of the human breast has been a major biological puzzle, mainly due to the fact that the mammary gland seems to be the only organ that is not fully developed at birth (1, 2). No other organ presents such dramatic changes in size, shape and function as does the breast during growth, puberty, pregnancy and lactation (2–4). It is agreed that the developmental phase of the human breast starts as early as the stage of nipple epithelium during embryonic development, continuing steadily with body growth, and undergoing a spurt of growth with lobule formation at puberty. Four different lobular structures have been characterized in the breast of postpubertal women, each one representing sequential developmental stages (3). Lobules type 1 are the most undifferentiated ones. They are also called virginal lobules because they are present in the immature female breast before menarche; and they are composed of clusters of 6 to 11 ductules per lobule. Lobules type 2 evolve from the previous ones and have a more complex morphology, being composed of a higher number of ductular structures per lobule. They progress to lobules type 3 which are characterized by having an average of 80 ductules or alveoli per lobule. They are frequently seen in the breast of women under hormonal stimulation or during pregnancy. Lobules type 4 have been described to be present during the lactational period of the mammary gland, but they are not found in the breast of nulliparous post-pubertal women. Lobules type 4 are considered to be the maximal expression of development and differentiation (3).