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Multi-row-per-track discrete bit patterned media with interleaved bits have been fabricated on granular perpendicular media disks by focused ion beam and tested by magnetic force microscopy and spinstand tester. It was found that sub-100 nm patterned magnetic islands showed single domain behavior and narrowed switching field distribution. We further demonstrate from captured spinstand readback waveforms the concept of recording two rows of interleaved dot bits as one track. In addition to overcoming the down track patterning resolution limit, the proposed concept patterned media provide many other advantages including higher data rate for read/write, a flexible bit aspect ratio (BAR)≥2 design for better integration with head design and servo control, as well as allowing the use of wider write pole to improve writing efficiency for high density recording. [ABSTRACT FROM AUTHOR]

In this paper, the real time thermal effect of the heat-assisted magnetic recording (HAMR) on the slider is investigated with the HAMR platform. The net temperature rises of the slider caused by laser absorption and heat radiation of the locally heated recording magnetic disk are studied by monitoring the calibrated read sensor resistances in different rotation speeds. The maximum slider temperature increase of about 3.5 °C caused by the locally heated recording disk is obtained when the media net temperature increase is 85 °C at 2000 rpm rotation speed. A higher temperature case is also discussed. [ABSTRACT FROM AUTHOR]

Investigates bit-shift performance at different skew angles and for media with different orientation. Comparison of normalized bit-shift values; Function of rotary actuators and bit-shift analysis; Impact of the skew angle on the off-track capability and media with different orientations.

We report an electrically controlled magnetism in a real recording system with CoCrPt–TiO2 nanocomposite thin films as recording medium. We show that in a spin-stand test, with a small voltage of 3 V applied across the head-media gap during recording, a 13% reduction of saturation current was observed and the read back waveforms showed sharper transitions. These account for the 3 dB improvement in read back signal-noise-ratio of the written magnetic information. The improved recording performance is mainly attributed to the reduction of anisotropy of the recording medium in the presence of electrical field. Simulations were carried out to understand the magnetization reversal process under applied electric and magnetic fields. [ABSTRACT FROM AUTHOR]

A novel lubricant with good thermal stability (Td = 328 °C) is developed for the application of heat-assisted magnetic recording (HAMR) media to achieve the areal density of 1 Tb/in² and beyond. Compared to currently-used commercial lubricants, the newly developed lubricant film can resist the laser irradiation without damage while Z-dol film is completely depleted under the same experimental conditions. Frictional coefficient and dewetting behavior are also superior to the candidate for HAMR media protection. [ABSTRACT FROM AUTHOR]

Objective: To investigate the related factors for lymph node metastasis (LNM), especially for high volume LNM (>5 metastatic lymph nodes) in papillary thyroid carcinoma (PTC). Methods: The medical records of 2 073 consecutive PTC patients who underwent lobectomy, near-total thyroidectomy or total thyroidectomy with ipsilateral or bilateral central lymph node dissection in Department of General Surgery, Peking Union Medical College Hospital from November 2013 to October 2014 were reviewed. Clinical and pathological features were collected. Univariate and multivariate analysis were performed to identify the related factors for LNM/high volume LNM. Results: In all 2 073 patients, LNM and high volume LNM were confirmed in 936 (45.15%) cases and 254 (12.25%) cases respectively. In univariate analysis, large tumor size, young patients (<40 years), male were associated with both LNM and high volume LNM. In multivariate analysis, tumor size >2.0 cm, young patients (<40 years), male were independent related factors of LNM ( OR =5.262, 95% CI: 3.468 to 7.986; OR =2.447, 95% CI: 2.000 to 2.995; OR =1.988, 95% CI: 1.593 to 2.480, respectively, all P =0.000) and high volume LNM ( OR =6.687, 95% CI: 4.477 to 9.986; OR =2.975, 95% CI: 2.224 to 3.980; OR =2.354, 95% CI: 1.737 to 3.191, respectively, all P =0.000). In 1 414 PTMC patients, a similar result was also demonstrated.Compared with young patients (<40 years), old patients (≥60 years) had lower incidence of LNM (25.47% vs . 52.24%, χ(2)=62.903, P =0.000) and high volume LNM (1.89% vs . 13.18%, χ(2)=37.341, P =0.000). Additionally, old patients also had lower risk of both LNM ( OR =0.316, 95% CI: 0.194 to 0.517, P =0.000) and high volume LNM ( OR =0.142, 95% CI: 0.034 to 0.599, P =0.000). Conclusions: The tumor size was the main related factor for both LNM and high volume LNM in PTC. The treatment should be more active in patients with tumor size >2 cm with consideration of higher incidence and risk for LNM and high volume LNM. Young patient was another important related factor for LNM and high volume LNM. In PTMC, old patients had lower incidence and risk for both LNM and high volume LNM. Dynamic observation or less surgical extent could be an option for these patients.

Objective: To investigate the influences of genomic DNA methylation upon neuroglobin sustained expression in oxygen- glucose deprivation model. Methods: With A549 cell strain as the research object, the control group were cultivated in the complete medium containing 10 μmol/L of 5-azacytidine for 4 days, and the control group was cultivated in the complete medium for 4 days.Then carried out oxygen glucose deprivation treatment for 4 h.Detecting neuroglobin expression, DNA methyltransferase expression, cell inhibition ratio and DNA methylation level at different time points. Results: DNA methylation level of the experimental group declined apparently[6 h : (1.0±0.0) vs (2.1±0.3); 12 h: ( 0.9±0.0) vs (1.4±0.0); 24 h: (0.9±0.0) vs (2.6±0.2); 36 h: (0.9±0.0) vs (2.9±0.1)], neuroglobin expression of the experimental group continued and was obviously higher than that of the control group at the same time point[NGB-PCR: 6 h: (3.3±1.1) vs (0.4±0.1); 12 h: (3.2±0.8) vs (0.1±0.1); 24 h: (4.6±0.6) vs (0.2±0.0); 36 h : (5.1±0.3) vs (0.1±0.1)], while the Cell inhibition ratio of the experimental group was obviously lower than that of the control group at the same time point[(6 h: (10.4±0.5) vs (14.1±0.7); 12 h: (22.0±1.3) vs (35.1±0.5); 24 h: (25.7±1.0) vs (40.6±1.3); 36 h: (30.0±0.8) vs (44.4±0.7)], differences had statistical significance ( P <0.05).mRNA expression of three methyltransferases of the experimental group was higher than that of the control group at different time points, where, DNMT1 and DNMT3B showed great differences ( P <0.05), while differences in DNMT3A of two groups had no statistical significance ( P >0.05). Conclusions: In the OGD/R model of A549 cell strain, genomic DNA methylation resulted in unsustained expression of neuroglobin, but neuroglobin expression increased after demethylation inhibitor was used.

Triptolide (TPL) is a diterpenoid triepoxide derived from the Chinese herb Tripterygium wilfordii and possesses anti-tumor activity against a range of cancer cells. However, the effect of TPL on prostate cancer cells and its potential to overcome multidrug resistance (MDR) have not been explored. Therefore, in this study we used prostate cancer cell line DU145 as the experimental model and established DU145/ADM cell line resistant to adriamycin (ADM). Our results showed that TPL inhibited the proliferation and induced the cell cycle arrest and apoptosis of DU145 cells in a dose and time dependent manner. TPL decreased the levels of Cyclin D1 and anti-apoptotic protein Bcl-2, and increased the levels of pro-apoptotic proteins Fas and Bax. Furthermore, we found that TPL restored the sensitivity DU145/ADM cells to ADM in a dose dependent manner, and this was accompanied by the inhibition of MDR1 expression at both mRNA and protein levels. Taken together, these results provide strong evidence that TPL overcomes MDR in prostate cancer cells by downregulating MDR1 expression, and suggest that TPL is a promising agent for prostate cancer therapy, especially for chemoresistant prostate cancer.

In order to assess possible enhancement of biopesticide activity, the fusion gene of crystal protein gene cry1Ac with the insect-specific neurotoxin ω-ACTX-Hv1a gene and egfp was expressed in Bacillus thuringiensis acrystalliferous strain Cry-B under the control of the native gene expression system. The fusion recombinant Cry-B(1Ac-ACTX-EGFP) generally produced two or three small crystal-like inclusion bodies in each cell and the GFP signal could be clearly observed. A 166 kDa full-length fusion protein was identified by immunoblot analysis. Virulence of the fusion inclusions was at least fivefold higher toward larvae of Spodoptera exigua. These results demonstrated that a foreign protein could be expressed and accumulate as parasporal inclusions in B. thuringiensis by C-terminal fusion with the native endotoxin while retaining partial insecticidal activity.

Steroids and neuropeptides interact in the central nervous system (CNS) to regulate reproductive function and behavior. The preoptic regulatory factors, PORF-1 and PORF-2, are unique neuropeptides for which roles in gender-related brain development and function have been proposed. PORF-1 and PORF-2 expression in rat brain are age, region and gender dependent, and castration or hypophysectomy alter the metabolism of the PORF-1 and PORF-2 mRNAs in male rat brain and testes. If these two peptides have a role in gender-dependent brain function, then gonadal steroids might well affect their expression. The present study was designed to investigate the response of the PORF-1 and PORF-2 mRNAs to sex steroids in the female rat brain and to compare this response to that of two peptides whose roles in the neuroendocrinology of reproduction are well established, gonadotropin-releasing hormone (GnRH) and neuropeptide Y (NPY). Rats were ovariectomized and treated with placebo, estradiol (E2), progesterone (P4) or a combination of the two (E2/P4) and NPY, PORF-2, GnRH and PORF-1 mRNAs were quantified by nuclease protection assays. PORF-1, PORF-2 and GnRH mRNAs were also measured in intact rats during estrus and proestrus. Responses were compared in the preoptic anterior hypothalamus (POA), medial basal hypothalamus (MBH), cerebral cortex (CC) and hippocampus (HIPP). Expression of PORF-1 and PORF-2 was also confirmed in the female rat hypothalamus by in situ hybridization analysis. PORF-1 and PORF-2 mRNAs were detected in the adult female rat brain by both in situ hybridization and ribonuclease protection analyses. In situ hybridization analysis demonstrated that PORF-1 and PORF-2 mRNAs are expressed in hypothalamic neurons. RNase protection analysis showed that PORF-1, PORF-2 and NPY mRNAs were present in all four brain regions examined while GnRH expression was detected only in the MBH and POA. Estradiol alone upregulated expression of the PORF-1 and PORF-2 mRNAs in the ovariectomized rat in the POA and HIPP, and of NPY mRNA in the MBH and HIPP. Progesterone alone had a stimulatory effect on NPY mRNA in the MBH and HIPP. Treatment with a combination of E2/P4 downregulated PORF-2 mRNA in the POA as well as PORF-1, PORF-2 and NPY mRNAs in the CC. In contrast, E2/P4 upregulated the PORF-2 and NPY mRNAs in the HIPP and NPY mRNA in the MBH. In the cycling rat, PORF-1 mRNA levels were higher during proestrus than estrus in both the MBH and POA, while PORF-2 mRNA levels did not change. In contrast GnRH mRNA was lower in the POA and higher in the MBH during proestrus compared with estrus. Thus, intrinsic factors, most likely both ovarian and neuroendocrine, regulate PORF-1 and GnRH expression in the intact cycling rat CNS in a region-dependent manner. In the ovariectomized rat, PORF-1, PORF-2, NPY and GnRH mRNAs all respond in a region-specific manner to sex steroid treatment. These data support the role of PORF-1 and PORF-2 in gender-dependent brain function in the adult female rat.

There is evidence that the conserved glutamine at residue 54 in the beta-subunit of human LH and and CG (hCG) is important for biological activity. Mutation to Arg in LH has been reported to impair receptor binding, leading to a documented case of hypogonadism, whereas in hCG the mutation has been shown to result in defective subunit association. Functional distinctions between LH and hCG have been described, but the significance of peptide-chain differences between the two has not been investigated systematically. We therefore compared the role of Gln-54 and its neighboring residues in both hormones, through replacement by amino acids with contrasting properties using site-directed mutagenesis. The mutant subunits were coexpressed with alpha-subunit in mammalian (Chinese hamster ovary) cells and the secreted hormones assayed for heterodimer formation, receptor binding, and steroidogenesis in murine Leydig cell tumor (MA-10) cells. Basic (Arg, Lys) substitution for Gln-54 in either hormone markedly impaired subunit association (<20% of wild-type) and the heterodimers that were formed were inactive (<5% of wild-type) in both assays. Arg-substituted hCG was also inactive in an adenylate cyclase assay using HEK-293 cells expressing rat LH/hCG receptor. After acidic (Glu) or neutral (Ala) substitution, heterodimer formation was less impaired (50-60% of wild-type), but effects on receptor interaction differed between the two hormones. The LH mutants still lacked binding activity, whereas the hCG products were fully active. The importance of residue 54 for receptor interaction appears to be sharply localized because mutation at adjacent positions (Pro-53 and Val-55) did not impair the activity of either hormone. Diminished heterodimer formation by Ile-53 mutation in LH (but not hCG), together with the similar effects of basic mutations at 54, imply long-distance effects as these residues are remote from alpha in the crystal structure. Our findings indicate that position 54 in LH and hCG is a determinant for both subunit association and receptor interaction. The differing responses between LH and hCG to certain mutations suggest that structural characteristics of the peptide chains may confer functional differences despite their close sequence homology.

Hormone-responsive peptides play a vital role in development and regulation of testicular function. The preoptic regulatory factors, porf-1 and porf-2, were originally discovered in the rat brain, but are also expressed in the rat and human testis. In the brain expression is age-related, hormone-responsive, region- specific, and gender-related, suggesting that porf-1 and porf-2 are involved in gender-specific brain development and function. Tissue-specific porf-1 and porf-2 mRNAs are also found in the testis and hypophysectomy may alter testicular porf-2 expression. It was thus of interest to further examine porf-1 and porf-2 expression in the testis to evaluate their potential as hormone-responsive peptides that regulate testicular development and function. Testicular expression of both porf-1 and -2 was analyzed as a function of maturational stage, aging and hypophysectomy by the solution hybridization/nuclease protection assay, and cellular location determined by in situ hybridization histochemistry. Expression was quantitatively compared in normal male rats at 15, 30 and 60 d (n = 4) and at 2, 6, 12, and 24 mo of age (n = 5). During development porf-1 is expressed at a constant level at 15, 30 and 60 d, then declines significantly with advancing age; levels at 24 mo are only 20% of those seen at 2 mo (p < 0.05). In contrast, porf-2 expression is highest at 15 d of age and steadily declines at 30 and 60 d, plateaus in the mature adult (6 and 12 mo), then exhibits an additional significant decline in the aged 24 mo animals (6 vs 24 mo, p < 0.05). Hypophysectomy of young adult rats at day 42 results in increased testicular expression 12 d later of both porf-1 (p < 0.05) and porf-2(p < 0.005) compared to intact 54-d-old rats (n = 5). In situ hybridization histochemistry confirms that both porf-1 and porf-2 are expressed in the mature testis at 60 d of age. Porf-2 mRNA is localized to immature germ cells including spermatogonia and primary spermatocytes. Porf-1 mRNA is associated with mature sperm and at low levels in the Sertoli cell cytoplasm surrounding spermatocytes. These data suggest that porf-2 is a pituitary hormone-responsive factor in the developing testis and that both porf-1 and porf-2 have cell-type specific functions in the germ cell compartment of the mature testis