Construction of a recombinant plasmid harbouring the glyceraldenyde-3-phosphate dehydrogenase gene of periodic Brugia malayi and observation on DNA immunity

PURPOSE

Controlling and eliminating lymphatic filariasis will require further research of preventative measures and implementation. Parasite is dependent on glycolysis for ATP production. The glycolytic enzyme glyceraldenyde-3-phosphate dehydrogenase (GAPDH) plays an important role in glycolysis and therefore is either a potential target for anti-parasite drug development or a vaccine candidate. Therefore, we tried to investigate the DNA vaccine-elicited immune responses in BALB/c mice.

MATERIALS AND METHODS

We cloned a gene encoding the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from periodic Brugia malayi into vector pcDNA3.1. Mice were injected at a dosage of 100 μg recombinant plasmid DNA with CpG intramuscular injection and immunized three times at 2-week intervals. pcDNA3.1 and normal saline were used as control. The tissue of muscles at the 4 weeks after the third injection was collected and target genes were detected using RT-PCR. The humoral responses elicited in mice by inoculation with the recombinant plasmid pcDNA3.1-BmGAPDH were detected using a standard ELISA. Two weeks after the third immunization, stimulation index (SI) was measured using the MTT method and the level of secreted IL-4 and INF-g were detected using ELISA.

RESULTS

Specific gene fragment coding GAPDH was amplified and the recombinant plasmid pcDNA3.1-BmGAPDH was constructed. Post-challenge sera from the mice immunized with the DNA vaccine had specific antibody titres of 1:1600 to 1:6400, and the highest titre was observed in the mice that were inoculated by pcDNA3.1-BmGAPDH/CpG at 6 weeks. At 4 weeks after immunization, the spleens of the mice were obviously enlarged. The proliferation of spleen T lymphocytes seen on the MTT assay was higher in the pcDNA3.1-BmGAPDH group than in the control group (P value <0.05). The levels of IL-4 and INF-γ in serums from the immunized mice were significantly higher than that of the control (P value <0.05).

CONCLUSIONS

We conclude that the recombinant eukaryotic plasmid pcDNA3.1-BmGAPDH could elicit humoral and cellular immune responses in mice.

MiR-155 inhibits the sensitivity of lung cancer cells to cisplatin via negative regulation of Apaf-1 expression

MicroRNA-155 (miR-155) overexpression is often found in malignancies including lung cancer. The objective of this study is to verify the hypothesis, based on the results of bioinformatics analysis, that miR-155 modulates cellular apoptosis and DNA damage through the regulation of Apaf-1 and is thus involved in the development and progression of lung cancer. First, we measured the expression of miR-155 and the Apaf-1 protein in lung cancer tissues. The results showed that expression of miR-155 was significantly higher in lung cancer tissues than in paracancerous and normal tissues; whereas Apaf-1 expression was lower in the lung cancerous tissues. We then established miR-155-silenced and Apaf-1-overexpressed A549 cell lines by transfection with pMAGic2.0-BIC-siRNA and pcDNA3.1-Apaf-1, respectively. These cell lines were then treated with cisplatin, and apoptosis and DNA damage were assessed, with non-transfected A549 cells used as negative controls. The results showed that, relative to controls, the silencing of miR-155 resulted in elevated expression of the Apaf-1 protein, whereas Apaf-1 mRNA levels remained unchanged. Both the silencing of miR-155 and the overexpression Apaf-1 greatly increased the sensitivity of A549 cells to cisplatin treatment, as evidenced by elevated rates of apoptosis and DNA damage. Furthermore, dual-transfection of A549 cells with miR-155 siRNA and Apaf-1 siRNA resulted in the attenuation of apoptosis and DNA damage. In conclusion, the inhibition of miR-155 can enhance the sensitivity of A549 cells to cisplatin treatment by modulation of cellular apoptosis and DNA damage through an Apaf-1-mediated pathway.

The soluble tachyzoite antigen of Toxoplasma gondii has a protective effect on mouse allografts

BACKGROUND

Infection with some types of parasites can significantly prolong allograft survival in mice. It is unknown whether the soluble tachyzoite antigen (STAg) from Toxoplasma gondii has the same effect and by what mechanism it acts.

METHODS

A mouse model of cardiac and skin allograft transplantation was established between BALB/c (H-2(d)) and C57BL/6(H-2(b)) mice. T gondii STAg was prepared, and 5 μg was administered subcutaneously to recipient mice 4 days before transplantation. The graft status was checked daily, and histologic and immunohistochemical assays were used to evaluate rejection. The serum cytokine levels from the recipient mice were analyzed by Luminex.

RESULT

The administration of 5 μg STAg 4 days before transplantation significantly prolonged the survival time of the heart and skin allografts to 85.17 ± 14.06 and 24.17 ± 2.32 days, respectively. Immunohistochemical staining showed that the CD4(+) and CD8(+) T lymphocytes were markedly reduced in the allografts at day 7 posttransplantation. Notably, interleukin (IL)-12, IL-2, and IL-17 levels were significantly reduced in the serum of mice treated with STAg compared with untreated mice 7 days after transplantation. In contrast, the levels of the antiinflammatory cytokine IL-10 were elevated.

CONCLUSION

A single administration of STAg before transplantation can significantly prolong the allograft survival time, which is accompanied by impaired lymphocyte infiltration and a reduced Th1 response.

Absence of a holelike fermi surface for the iron-based K0.8F1.7Se2 superconductor revealed by angle-resolved photoemission spectroscopy

We have performed an angle-resolved photoemission spectroscopy study of the new iron-based superconductor K(0.8)Fe(1.7)Se(2) (T(c)∼30 K). Clear band dispersion is observed with the overall bandwidth renormalized by a factor of 2.5 compared to our local density approximation calculations, indicating relatively strong correlation effects. Only an electronlike band crosses the Fermi energy, forming a nearly circular Fermi surface (FS) at M (π, 0). The holelike band at Γ sinks ∼90 meV below the Fermi energy, with an indirect band gap of 30 meV, to the bottom of the electronlike band. The observed FS topology in this superconductor favors (π, π) inter-FS scattering between the electronlike FSs at the M points, in sharp contrast to other iron-based superconductors which favor (π, 0) inter-FS scattering between holelike and electronlike FSs.

Effect of dietary fibre on reproductive performance of sows during the first two parities

The aim of this study was to investigate the effect of dietary fibre on reproductive performance during the first two parities. Gilts were randomly allocated to receive three fibrous diets from days 1-90 of gestation, including low fibre [low fiber (LF), 10.8% neutral detergent fiber (NDF), n=132], middle fibre [middle fiber (MF), 15.8% NDF, n=132] and high fibre diet (HF, 20.8% NDF, n=135), until completion of the second parity. Response criteria included backfat measurements, litter size and pig weight at parturition and day 22 of lactation, weaning-oestrus-interval, oestrus rate, sow farrowing and culling rate, uniformity of newborns and relative organ weights. The results showed sows fed LF diet in parity 1 gained more backfat (p<0.05) during gestation but lost more (p<0.05) during lactation than sows fed HF diet. Furthermore, sows fed LF diet farrowed more pigs (+0.7-1.1 pigs, p<0.05) and pigs born alive (+1.0 pigs, p<0.05) relative to sows fed HF diet. Likewise, sows fed LF and MF diets had greater litter weights at parturition (both p=0.06) and day 22 after lactation (both p<0.05). In parity 2, yet, it was MF diet to increase both total pigs born and pigs born alive (+0.9-1.1 pigs, p<0.05) and litter weight (p=0.05) relative to other diets. After 22 d of lactation, intriguingly, sows fed HF diet had most pigs alive (p<0.01-0.07) and heavier litter weight (p=0.07 or 0.2). Feeding HF diet also increased internal organs weight of newborns (p<0.05). Collectively, feeding LF and MF diets had beneficial effects on litter weight at parturition and day 22 of lactation in parity 1, and feeding MF diet until parity 2 was able to improve litter size and weight at parturition, but this positive effect disappeared after 22 days of lactation, instead feeding HF diet showed the optimal litter performance.

Electronic structure of optimally doped pnictide Ba0.6K0.4Fe2As2: a comprehensive angle-resolved photoemission spectroscopy investigation

The electronic structure of the Fe-based superconductor Ba(0.6)K(0.4)Fe(2)As(2) is studied by means of angle-resolved photoemission. We identify dispersive bands crossing the Fermi level forming hole-like (electron-like) Fermi surfaces (FSs) around Γ (M) with nearly nested FS pockets connected by the antiferromagnetic wavevector. Compared to band structure calculation findings, the overall bandwidth is reduced by a factor of 2 and the low energy dispersions display even stronger mass renormalization. Using an effective tight banding model, we fitted the band structure and the FSs to obtain band parameters reliable for theoretical modeling and calculation of physical quantities.

Transforming growth factor beta 1 plays an important role in inducing CD4(+)CD25(+)forhead box P3(+) regulatory T cells by mast cells

The role of mast cells (MCs) in the generation of adaptive immune responses especially in the transplant immune responses is far from being resolved. It is reported that mast cells are essential intermediaries in regulatory T cell (T(reg)) transplant tolerance, but the mechanism has not been clarified. To investigate whether bone marrow-derived mast cells (BMMCs) can induce T(regs) by expressing transforming growth factor beta 1 (TGF-β1) in vitro, bone marrow cells obtained from C57BL/6 (H-2(b) ) mice were cultured with interleukin (IL)-3 (10 ng/ml) and stem cell factor (SCF) (10 ng/ml) for 4 weeks. The purity of BMMCs was measured by flow cytometry. The BMMCs were then co-cultured with C57BL/6 T cells at ratios of 1:2, 1:1 and 2:1. Anti-CD3, anti-CD28 and IL-2 were administered into the co-culture system with (experiment groups) or without (control groups) TGF-β1 neutralizing antibody. The percentages of CD4(+)CD25(+)forkhead box P3 (FoxP3)(+) T(regs) in the co-cultured system were analysed by flow cytometry on day 5. The T(reg) percentages were significantly higher in all the experiment groups compared to the control groups. These changes were deduced by applying TGF-β1 neutralizing antibody into the co-culture system. Our results indicated that the CD4(+) T cells can be induced into CD4(+)CD25(+)FoxP3(+) T cells by BMMCs via TGF-β1.

Pressure-induced superconductivity in topological parent compound Bi2Te3

We report a successful observation of pressure-induced superconductivity in a topological compound Bi(2)Te(3) with T(c) of ∼3 K between 3 to 6 GPa. The combined high-pressure structure investigations with synchrotron radiation indicated that the superconductivity occurred at the ambient phase without crystal structure phase transition. The Hall effects measurements indicated the hole-type carrier in the pressure-induced superconducting Bi(2)Te(3) single crystal. Consequently, the first-principles calculations based on the structural data obtained by the Rietveld refinement of X-ray diffraction patterns at high pressure showed that the electronic structure under pressure remained topologically nontrivial. The results suggested that topological superconductivity can be realized in Bi(2)Te(3) due to the proximity effect between superconducting bulk states and Dirac-type surface states. We also discuss the possibility that the bulk state could be a topological superconductor.

Annexin-1 downregulation is associated with clinical outcome in Chinese patients with hilar cholangiocarcinoma

AIMS

Annexin A1 (ANXA1) is a calcium- and phospholipid-binding protein and has been implicated in regulating inflammatory responses, cell proliferation and apoptosis. The evidence of its importance in carcinogenesis increased rapidly. However, the status of ANXA1 in hilar cholangiocarcinoma remains unclear. Here, we detected ANXA1 expression and determined its clinical significance in Chinese patients with hilar cholangiocarcinoma.

METHODS

Tissue microarray blocks containing tumor specimens obtained from 61 patients were constructed. Expression of ANXA1 in these specimens was analyzed using immunohistochemical studies.

RESULTS

ANXA1 expression was observed in 27 cases (44.3%). Loss of ANXA1 expression was significantly associated with lymph node metastases and histopathologic grade. ANXA1 expression has a significant inverse correlation with recurrence and poor survival in univariate analyses.Multivariate analyses revealed that loss of ANXA1 expression was an independent predictor for future recurrence and overall survival in patients with cholangiocarcinoma.

CONCLUSIONS

Decreased expression of ANXA1 is a common event in human hilar cholangiocarcinoma and is significantly correlated with the poor outcome of patients with cholangiocarcinoma, suggesting a potential role of ANXA1 in cancer development and progression.

Measurement of the c-axis optical reflectance of AFe2As2 (A=Ba, Sr) single crystals: evidence of different mechanisms for the formation of two energy gaps

We present the c-axis optical reflectance measurement on single crystals of BaFe2As2 and SrFe2As2, the parent compounds of FeAs based superconductors. Different from the ab-plane optical response where two distinct energy gaps were observed in the spin-density-wave (SDW) state, only the smaller energy gap could be seen clearly for E∥c axis. The very pronounced energy gap structure seen at a higher energy scale for E∥ab plane is almost invisible. We propose a novel picture for the band structure evolution across the SDW transition and suggest different driving mechanisms for the formation of the two energy gaps.

YKL-40 in asthmatic patients, and its correlations with exacerbation, eosinophils and immunoglobulin E

The chitinase-like protein YKL-40, which binds chitin but lacks chitinase activity, has been found to be either the cause or a biomarker for asthma. The aim of our study was to investigate whether serum YKL-40 levels are increased in Chinese patients with asthma and identify its correlation to acute exacerbation, total serum immunoglobulin (Ig)E, the percentage of peripheral blood eosinophils and lung function. We quantified serum YKL-40 levels, total IgE levels and peripheral blood eosinophil percentages in patients with asthma, as well as in controls from the communities surrounding our hospital. The lung function of asthma subjects was also measured. Our data showed that the serum YKL-40 levels were significantly elevated in patients with asthma compared with controls and, when the asthma subjects were stratified, serum YKL-40 levels in the exacerbation group were higher than those in the stable and control groups. In addition, serum YKL-40 levels correlated positively with total serum IgE levels and the percentage of peripheral blood eosinophils, but correlated inversely with lung functions. Thus, we conclude that YKL-40 is found in increased quantities in the serum of Chinese patients with asthma, and its level correlates with exacerbation attacks, indicating that high levels of serum YKL-40 may be a biological characteristic of the exacerbation of asthma.

Observation of Dirac cone electronic dispersion in BaFe2As2

We performed an angle-resolved photoemission spectroscopy study of BaFe2As2, which is the parent compound of the so-called 122 phase of the iron-pnictide high-temperature superconductors. We reveal the existence of a Dirac cone in the electronic structure of this material below the spin-density-wave temperature, which is responsible for small spots of high photoemission intensity at the Fermi level. Our analysis suggests that the cone is slightly anisotropic and its apex is located very near the Fermi level, leading to tiny Fermi surface pockets. The bands forming the cone show an anisotropic leading edge gap away from the cone that suggests a nodal spin-density-wave description.

Silencing of HIF-1alpha suppresses tumorigenicity of renal cell carcinoma through induction of apoptosis

Hypoxia-inducible factor-1alpha (HIF-1alpha) is a main responder to intracellular hypoxia and is overexpressed in many human cancers, including renal cell carcinoma (RCC). To better understanding of the role of HIF-1alpha in the tumorigenicity of RCC, we used short-hairpin RNA (shRNA) interference to inhibit HIF-1alpha expression in the human renal cancer cell line, Caki-1 and OS-RC-2. Silencing of HIF-1alpha significantly reduced the expression of HIF-1alpha in both of renal cancer cell lines. In vitro downregulation of HIF-1alpha inhibited Caki-1 and OS-RC-2 cell growth, migration and invasion. The results further showed that HIF-1alpha silencing resulted in caspase-dependent apoptosis of Caki-1 and OS-RC-2 through regulation of PI3K/Akt pathway and Bcl-2-related proteins expression. In vivo animal studies showed that tumor growth was significantly inhibited in HIF-1alpha shRNA-transfected RCC. Intratumor gene therapy with polyethylenimine-loaded HIF-1alpha shRNA also resulted in tumor growth suppression. Thus, this study demonstrates that downregulation of HIF-1alpha could suppress tumorigenicity of RCC through induction of apoptosis, and HIF-1alpha shRNA may be a promising strategy for the treatment of RCC.

Observation of a novel orbital selective Mott transition in Ca(1.8)Sr(0.2)RuO(4)

We observed a novel orbital selective Mott transition in Ca(1.8)Sr(0.2)RuO(4) by angle-resolved photoemission. While two sets of dispersing bands and the Fermi surface associated with the doubly degenerate d(yz) and d(zx) orbitals are identified, the Fermi surface associated with the wider d(xy) band is missing as a consequence of selective Mott localization. Our theoretical calculations demonstrate that this orbital selective Mott transition is mainly driven by the combined effects of interorbital carrier transfer, superlattice potential, and orbital degeneracy, whereas the bandwidth difference plays a less important role.

Experimental realization of a three-dimensional topological insulator, Bi2Te3

Three-dimensional topological insulators are a new state of quantum matter with a bulk gap and odd number of relativistic Dirac fermions on the surface. By investigating the surface state of Bi2Te3 with angle-resolved photoemission spectroscopy, we demonstrate that the surface state consists of a single nondegenerate Dirac cone. Furthermore, with appropriate hole doping, the Fermi level can be tuned to intersect only the surface states, indicating a full energy gap for the bulk states. Our results establish that Bi2Te3 is a simple model system for the three-dimensional topological insulator with a single Dirac cone on the surface. The large bulk gap of Bi2Te3 also points to promising potential for high-temperature spintronics applications.

Investigation of phosphorylation site responsible for CaLP (P. fucata) nucleo-cytoplasmic shuttling triggered by overexpression of p21Cip1

Calmodulin (CaM) is a highly conserved and ubiquitous Ca(2+)-binding protein regulating intracellular Ca(2+) concentration by acting as a sensor of this divalent cation in eukaryotic cells. Being such a very important signal sensor, CaM is susceptible to undergo many posttranslational modifications. One of these important modifications is its phosphorylation. Our previous investigations showed that CaM and calmodulin-like protein (CaLP) cloned from Pinctada fucata have many different characteristics in spite of their high similarity to each other. We have narrowed down that the C-terminal domains of CaM and CaLP are responsible for their discrepant subcellular localizations and shuttling of CaLP when it is co-transfected with p21(Cip1), which is commonly considered as an important cell cycle regulating protein. In this study, we first predicted the potential phosphorylation site responsible for the shuttling and confirmed by fluorescence confocal microscopy. Together with fluorescence activated cell sorter analysis, we further investigated the releasing ability of wild type and point mutated CaLP from arrested cell cycle caused by p21(Cip1) overexpression. By performing pull-down analysis and phosphorylation status of CaLP in cytoplasm fraction of transfected COS-7 cells with CaLP alone and phosphorylation status of CaLP in nuclear fraction of co-transfected COS-7 cells with CaLP and p21(Cip), we propose that the CaLP staying in the cytoplasm is in the state of phosphorylation, but when p21(Cip1) is overexpressed in mammalian cells, some signal triggers CaLP dephosphorylation and translocation into the nucleus.

Molecular epidemiology of tuberculosis in England, 1998

SETTING

England.

OBJECTIVE

To investigate the proportion of tuberculosis (TB) cases attributable to recent transmission and factors associated with clustering.

DESIGN

Demographic, clinical and microbiological surveillance data were collated from all new culture-confirmed cases in 1998. Using insertion sequence (IS) 6110 restriction fragment length polymorphism (RFLP) typing, strains were classified as clustered (identical patterns) or unique and risk factors were determined using multivariable logistic regression.

RESULTS

RFLP patterns were available for 2265 of 3713 (61%) cases: 1808 had >or=5 IS6110 copies, while 372 cases were in 152 clusters, giving an estimated proportion due to recent transmission of 12.2%.Pulmonary disease (aOR 1.6; 95%CI 1.1-2.2), previous treatment (aOR 3.7; 2.2-6.5) and homelessness (aOR 5.5; 1.2-24.1) were independent risk factors for clustering. Fourteen per cent of patients of Indian subcontinent origin were clustered compared with 27% of white patients. Many clusters spanned ethnic groups (45%) and geographical regions (47%).

CONCLUSION

The calculated proportion of TB cases due to recent transmission is low.Adjusting for missed cases and study duration, it increases to 27.6%. Many cases may arise from reactivation or acquisition outside England. Transmission within England accounted for approximately one in four cases and occurred over wide geographic areas, between ethnic groups and among the homeless. Molecular epidemiology can inform local and national public health action.

Production of cloned miniature pigs by enucleation using the spindle view system

Porcine somatic cell nuclear transfer (NT) has been successfully performed, but its efficiency remains quite low. In this study, we improvised on the enucleation method to enhance the development of NT embryos. Initially, an experiment was performed to determine the location relationship between the metaphase plate and the first polar body, where the results showed that the metaphase plate may frequently be displaced during the varying period of maturation process. When the metaphase plates were removed using the 'blind' enucleation method, the enucleation rate was affected by the maturation time; however, when the spindle view system was used, an enucleation rate of 100% was achieved. In the next experiment, these two methods were used to construct embryos: the fusion efficiency was significantly higher (p < 0.01) in the spindle view system group and the development rates of the reconstructed embryos were significantly higher in the spindle view system group compared with the 'blind' enucleation group (p < 0.01). An average of 174 (141-210) cloned embryos from the spindle view system group were transferred into five surrogate pigs and one piglet was delivered at 114 days after embryo transfer by caesarean section. DNA analysis confirmed that the piglet was genetically identical to the male donor pig. We showed that enucleation by the spindle view system is the another new technique compare the handmade cloning method [Theriogenology 2007: 68, 1104] to promote the development of the reconstructed embryos, and that a full-term cloned pig could be produced using this method.

Synthesis of erbium hydroxide microflowers and nanostructures in subcritical water

The effects of temperature, pressure, pH, residence time and reactant concentrations, as well as the presence or absence of CO(2), on the size and morphology of erbium hydroxide particles synthesized in a hydrothermal batch reactor and a diamond-anvil cell (DAC) reactor have been investigated. Several new erbium-based microstructures and nanostructures were obtained that encompass different phases and shapes, including crystalline microflowers, hexagonal microlayers, microsticks and microspheres made from nanoparticles, as well as nanofibers, nanorods and nanolayers. The Er(2)OCO(3)(OH)(2) microflowers are pure, structurally uniform, and mostly free from dislocations. Their crystallinity, morphology, optical properties and structural features have been examined and compared with those of the other phases by field-emission scanning electron microscopy (SEM), x-ray diffraction (XRD), and energy-dispersive x-ray (EDX) analysis, and by Raman, infrared, UV-visible and fluorescence spectroscopy.

Bond-counting rule for carbon and its application to the roughness of diamond (001)

Despite that carbon is tetravalent identical to silicon, first-principles calculations reveal that stable step structures on diamond (001) are entirely different from those on silicon. Moreover, pristine Si(001) is flat; pristine diamond (001) could be rough due to negative step formation energies. A generic bond-counting rule is established, which should apply to most carbon structures where sp2 and sp3 hybrids coexist: e.g., it provides a qualitative account of the step energy order without detailed calculation. Our findings agree with experimental observations.

A surface-tailored, purely electronic, mott metal-to-insulator transition

Mott transitions, which are metal-insulator transitions (MITs) driven by electron-electron interactions, are usually accompanied in bulk by structural phase transitions. In the layered perovskite Ca(1.9)Sr(0.1)RuO4, such a first-order Mott MIT occurs in the bulk at a temperature of 154 kelvin on cooling. In contrast, at the surface, an unusual inherent Mott MIT is observed at 130 kelvin, also on cooling but without a simultaneous lattice distortion. The broken translational symmetry at the surface causes a compressional stress that results in a 150% increase in the buckling of the Ca/Sr-O surface plane as compared to the bulk. The Ca/Sr ions are pulled toward the bulk, which stabilizes a phase more amenable to a Mott insulator ground state than does the bulk structure and also energetically prohibits the structural transition that accompanies the bulk MIT.

Prediction of mitochondrial proteins based on genetic algorithm - partial least squares and support vector machine

Mitochondria are essential cell organelles of eukaryotes. Hence, it is vitally important to develop an automated and reliable method for timely identification of novel mitochondrial proteins. In this study, mitochondrial proteins were encoded by dipeptide composition technology; then, the genetic algorithm-partial least square (GA-PLS) method was used to evaluate the dipeptide composition elements which are more important in recognizing mitochondrial proteins; further, these selected dipeptide composition elements were applied to support vector machine (SVM)-based classifiers to predict the mitochondrial proteins. All the models were trained and validated by the jackknife cross-validation test. The prediction accuracy is 85%, suggesting that it performs reasonably well in predicting the mitochondrial proteins. Our results strongly imply that not all the dipeptide compositions are informative and indispensable for predicting proteins. The source code of MATLAB and the dataset are available on request under liml@scu.edu.cn.

Effects of different chemotherapy regimens and tamoxifen for HER2 over-expressed breast cancer adjuvant therapy

11048

Background: To evaluate effects of different adjuvant chemotherapy regimens and TAM in HER-2-overexpressed breast cancer patients. Methods: To study 1625 primary breast cancer cases after operation from 2002.7 to 2005.11 given adjuvant chemotherapy ,600 cases given CMF, 600 cases given CEF, and 425 cases given T-regimen (anthracyclines follow taxanes),1090 HR+ cases given tamoxifen. HER-2 expression were measured by immunohistochemistry (IHC). Median follow-up time is 42 months. Results: (1)3yr DFS of HER-2 over-expression is inferior to HER-2 negative ones in CMF group(p<0.05), no difference between HER-2- overexpressed and HER-2-negative group treated with either CEF or taxanes-based regimen (p>0.05). Subgroup analysis suggested: patients treated with CMF, 3yr DFS of HER-2 over-expression is inferior to HER-2-negative ones in node-positive subgroup, but no difference in node-negative ones; HER-2 expression has no influence on effects of CEF or T-regimen in node-positive or node-negative subgroup. (2) 425 HER-2 over-expressed patients(183 cases given CMF , 121 cases given CEF , and 121 cases given T-regimen): compared to CMF, anthracyclines and taxanes are more effective, but no difference between anthracyclines and T-regimen. (3) 235 patients with HER-2 over- expression and node-postive (72 cases given CMF , 68 cases given CEF, and 95 cases given T-regimen):, anthracyclines and taxanes are more effective than CMF, but no difference between anthracyclines and T-regimen. (4)3yr DFS is 91.23% in HER-2 over-expressed group and 93.42% in HER-2-negative group (p=0.04) with TAM. HER-2 over-expressed patients are resistant to TAM. (5) Subgroup analysis suggested that: 3yr DFS is 88.67% with HER-2 over-expression and 92.20% with HER-2-negative in postmenopausal node-positive subgroup(p=0.0069), postmenopausal patients with HER-2 over-expression and node-positve are resistant to TAM; no difference in either premenopausal or postmenopausal node-negative subgroup (p>0.05). Conclusions: No difference between Anthracyclines based and T-regimens for HER2 over-expressed patients with node-positive for 3yr DFS.Postmenopausal ER+/PR+ patients with HER2 over- expression are resistant to Tamoxifen endocrine therapy.

No significant financial relationships to disclose.

Trace organic contamination in biota collected from the Pearl River Estuary, China: a preliminary risk assessment

The marine ecosystem of the Pearl River Delta, located on the southern coast of China, has been heavily exploited following the rapid economic growth that has occurred since the 1980s. This investigation aimed to elucidate trace organic contamination in marine biota inhabiting the Pearl River Delta area. Biota samples, including green-lipped mussels (Perna viridis), oysters (Crassostrea rivularis) and shrimp (Penaeus orientalis) were sampled from 16 stations fringing the Estuary. Elevated concentrations (on a dry weight basis) of polycyclic aromatic hydrocarbons (27.8-1041.0 ng/g), petroleum hydrocarbons (1.7-2345.4 microg/g), polychlorinated biphenyls (2.1-108.8 ng/g), DDTs (1.9-79.0 ng/g), and hexachlorocyclohexanes (n.d.-38.4 ng/g) were recorded. A human health risk assessment was conducted to estimate the risk to local residents associated with the consumption of biota collected from the Pearl River Estuary. The results indicated that PCBs were at levels that may cause deleterious health effects in populations that consume large amounts of seafood. However, it would be instructive to establish health criteria for trace organic contaminants that are specific to the local populations, in order to derive a more accurate and relevant health risk assessment.

Sensory neurite outgrowth on white matter astrocytes is influenced by intracellular and extracellular S100A4 protein

The central nervous system (CNS) is considered a nonpermissive environment for axonal regeneration because of the presence of myelin and associated repulsive molecules. However, neural cells transplanted to the CNS preferably migrate and extend their fibers in white matter areas. We previously showed that white matter astrocytes in vivo express the calcium-binding protein S100A4, which is strongly up-regulated in areas of white matter degeneration. To investigate the role of white matter astrocytes and their specific protein S100A4 in axonal regeneration, we developed white matter astrocyte cultures with strong S100A4 expression and grew dissociated adult dorsal root ganglion (DRG) cells on top of astrocytes for 24 hr. By using small interfering S100A4 RNA, we were able to eliminate S100A4 expression and compare growth of DRG cell neurites on S100A4-silenced and S100A4-expressing astrocytes. In addition, we studied whether extracellular S100A4 has an effect on neurite growth from adult DRG cells cultured on S100A4-expressing white matter astrocytes. Our data show that white matter astrocytes are permissive for neurite growth, although high levels of S100A4 in white matter astrocytes have a negative effect on this growth. Extracellular application of S100A4 induced extensive growth of DRG cell neurites on white matter astrocytes. These findings suggest that white matter astrocytes are able to support axonal regeneration and, furthermore, that administration of extracellular S100A4 provides strong additional support for axonal regeneration.

A synergistic effect between PG490-88 and tacrolimus prolongs renal allograft survival in monkeys

This study was undertaken to determine if PG490-88 and tacrolimus (Tac) act synergistically to prevent renal allograft rejection in monkeys and to explore possible mechanisms of synergy between these agents. MHC-mismatched renal allografts were transplanted into cynomolgus monkeys after bilateral nephrectomy. Recipients were divided into the following groups: (i) no treatment; (ii) PG490-88 (0.03 mg/kg); (iii) Tac (1 mg/kg); (iv) PG490-88 (0.01 mg/kg) + Tac (1 mg/kg) and (v) PG490-88 (0.03 mg/kg) + Tac (1 mg/kg). Through synergy PG490-88 and Tac inhibited anti-CD3/PMA-induced T-cell proliferation and IFN-gamma expression in vitro. Tac monotherapy only marginally prolonged survival (27 +/- 3.2 days), while the combination of PG490-88 and Tac significantly prolonged graft survival to a median of 99 days (PG490-88 at 0.03 mg) and 38.5 days (PG490-88 at 0.01 mg/kg). Prolonged survival correlated with inhibited IgM production as well as reduced T-cell infiltration, IL-2 protein expression and NF-AT/NF-kappaB activity. We conclude that PG490-88 and a subtherapeutic dose of Tac significantly prolong renal allograft survival in monkeys through the synergistic inhibition of T-cell activation and a decrease in IFN-gamma production and NF-AT/NF-kappaB activity.

Prediction of longitudinal cognitive decline in normal elderly with subjective complaints using electrophysiological imaging

An extensive literature reports changes in quantitative electroencephalogram (QEEG) with aging and a relationship between magnitude of changes and degree of clinical deterioration in progressive dementia. Longitudinal studies have demonstrated QEEG differences between mild cognitively impaired (MCI) elderly who go on to decline and those who do not. This study focuses on normal elderly with subjective cognitive complaints to assess the utility of QEEG in predicting future decline within 7 years. Forty-four normal elderly received extensive clinical, neurocognitive and QEEG examinations at baseline. All study subjects (N = 44) had only subjective complaints but no objective evidence of cognitive deficit (evaluated using the Global Deterioration Scale [GDS] score, GDS stage = 2) at baseline and were re-evaluated during 7-9 year follow-up. Baseline QEEGs of Decliners differed significantly (p < 0.0001, by MANOVA) from Non-Decliners, characterized by increases in theta power, slowing of mean frequency, and changes in covariance among regions, especially on the right hemisphere. Using logistic regression, an R2 of 0.93 (p < 0.001) was obtained between baseline QEEG features and probability of future decline, with an overall predictive accuracy of 90%. These data indicate high sensitivity and specificity for baseline QEEG as a differential predictor of future cognitive state in normal, subjectively impaired elderly.

Intracellular calcium-binding protein S100A4 influences injury-induced migration of white matter astrocytes

Astrocytes play a crucial role in central nervous system (CNS) pathophysiology. White and gray matter astrocytes are regionally specialized, and likely to respond differently to CNS injury and in CNS disease. We previously showed that the calcium-binding protein S100A4 is exclusively expressed in white matter astrocytes and markedly up-regulated after injury. Furthermore, down-regulation of S100A4 in vitro significantly increases the migration capacity of white matter astrocytes, a property, which might influence their function in CNS tissue repair. Here, we performed a localized injury (scratch) in confluent cultures of white matter astrocytes, which strongly express S100A4, and in cultures of white matter astrocytes, in which S100A4 was down-regulated by transfection with short interference (si) S100A4 RNA. We found that S100A4-silenced astrocytes rapidly migrated into the injury gap, whereas S100A4-expressing astrocytes extended hypertrophied processes toward the gap, but without closing it. To explore the involvement of S100A4 in migration of astrocytes in vivo, we induced focal demyelination and transient glial cell elimination in the spinal cord white matter by ethidium bromide injection in S100A4 (-/-) and (+/+) mice. The results show that astrocyte migration into the demyelinated area is promoted in S100A4 (-/-) compared to (+/+) mice, in which a pronounced glial scar was formed. These data indicate that S100A4 reduces the migratory capacity of reactive white matter astrocytes in the injured CNS and is involved in glial scar formation after injury.

Serum DDT, age at menarche, and abnormal menstrual cycle length

BACKGROUND

Although dichlorodiphenyl trichloroethane (DDT) exposure is known to affect human endocrine function, few previous studies have investigated the effects of DDT exposure on age at menarche or menstrual cycle length.

METHODS

A cross sectional study was conducted to study the effects of DDT exposure on age at menarche and menstrual cycle length among 466 newly married, nulliparous female Chinese textile workers aged 20-34 years enrolled between 1996 and 1998. Serum was analysed for DDT and its major metabolites. Multivariate linear regression was used to estimate DDT exposure effects on age at menarche and multivariate logistic regression was used to estimate DDT exposure effects on odds of experiencing short or long cycles.

RESULTS

Relative to those in the lowest DDT quartile, the adjusted mean age at menarche was younger in those in the fourth quartile (-1.11 years). Modeled as a continuous variable, a 10 ng/g increase in serum DDT concentration was associated with an adjusted reduction in age at menarche of 0.20 years. Relative to those in the lowest DDT quartile, odds of any short cycle (<21 days) in the previous year were higher for those in the fourth quartile (odds ratio = 2.78; 95% CI 1.07 to 7.14). There were no associations between serum DDT concentrations and odds of experiencing a long cycle (>40 days).

CONCLUSION

Results suggest that DDT exposure was associated with earlier age at menarche and increased risk of experiencing a shortened menstrual cycle.

Eugenol inhibits calcium currents in dental afferent neurons

Eugenol is a topical analgesic agent widely used in the dental clinic. To elucidate the molecular mechanism underlying its analgesic action, we investigated the effect of eugenol on high-voltage-activated calcium channel (HVACC) currents in dental primary afferent neurons, and with a heterologous expression system. Dental primary afferent neurons were identified by retrograde labeling with a fluorescent dye, DiI. Eugenol inhibited HVACC currents in both capsaicin-sensitive and capsaicin-insensitive dental primary afferent neurons. The HVACC inhibition by eugenol was not blocked by capsazepine, a competitive transient receptor potential vanilloid 1 (TRPV1) antagonist. Eugenol inhibited N-type calcium currents in the cell line C2D7, stably expressing the human N-type calcium channels, where TRPV1 was not endogenously expressed. Our results suggest that the HVACC inhibition by eugenol in dental primary afferent neurons, which is not mediated by TRPV1 activation, might contribute to eugenol's analgesic effect.

ABBREVIATIONS

high-voltage-activated calcium channel, HVACC; transient receptor potential vanilloid 1, TRPV1; trigeminal ganglion, TG; dorsal root ganglion, DRG; capsazepine, CZP.

Sign changes of intrinsic spin Hall effect in semiconductors and simple metals: first-principles calculations

First-principles calculations are applied to study spin Hall effect in semiconductors and simple metals. We found that intrinsic spin Hall conductivity (ISHC) in realistic materials shows rich sign changes, which may be used to distinguish the effect from the extrinsic one. The calculated ISHC in n-doped GaAs can be well compared with experiment, and it differs from the sign obtained from the extrinsic effect. On the other hand, the ISHC in W and Au, which shows opposite sign, respectively, is robust and not sensitive to the disorder.

Risks posed by trace organic contaminants in coastal sediments in the Pearl River Delta, China

Local marine environments in China's Pearl River Delta (PRD), the most rapidly developing region in one of the world's fastest growing economies, have been experiencing significant environmental stress during the past decades. This investigation was conducted to determine the status and trends of persistence organic pollutants (POPs) such as polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons (PHCs), polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides and dioxin-related compounds in marine sediments collected from sixteen coastal stations in the Pearl River Delta (PRD) in March 2003. Elevated concentrations of PAHs (94-4300 ng/g), PCBs (6.0-290 ng/g), PHCs (14-150 microg/g), and DDTs (1.4-600 ng/g) were detected in sediment samples. In addition, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like activities in the sediment samples were estimated to range from 0.3 to 440 pg TCDD-EQ/g. Sediments collected from Xiashan contained the greatest concentrations of trace organic contaminations amongst all the sampling stations in the present study. The degree of trace organic contamination was, in general, more severe at stations situated along the west shores of the PRD than their counterparts in the east. A preliminary assessment was performed to examine the probable risks to the marine ecosystem due to POPs. The results showed that OC pesticide contamination in the PRD was particularly serious and might pose a threat to the health of the marine inhabitants.