Targeting T cells against brain tumors with a bispecific ligand-antibody conjugate

Haemophilus influenzae is a bacterium of medical interest of which the entire genome has been sequenced. The proteome of the microorganism has been analyzed by two-dimensional gel electrophoresis, during which immobilized pH 3-10 gradient strips were used and approximately 300 proteins were identified. In order to detect additional, basic proteins, we analyzed the soluble protein fraction of H. influenzae and the proteins of fractions collected from affinity chromatography on heparin, by two-dimensional gel electrophoresis, using for the first-dimensional separation immobilized pH gradient strips comprising the pH region of 6-11. The protein spots were analyzed by matrix-assisted laser desorption ionization-mass spectrometry. One hundred and two proteins were identified, of which 58 were identified for the first time. A large percentage of the basic proteins represent nucleic acid binding and, in particular, ribosomal proteins. The locations of the identified basic proteins of H. influenzae are indicated in a two-dimensional map.     

GC–MS analysis of oxysterols and their formation in cultivated liver cells (HepG2)

Oxysterols play a key role in many (patho)physiological processes and they are potential biomarkers for oxidative stress in several diseases. Here we developed a rapid gas chromatographic-mass spectrometry-based method for the separation and quantification of 11 biologically relevant oxysterols bearing hydroxy, epoxy, and dihydroxy groups. Efficient chromatographic separation (resolution ≥ 1.9) was achieved using a medium polarity 35%-diphenyl/65%-dimethyl polysiloxane stationary phase material (30 m × 0.25 mm inner diameter and 0.25 μm film thickness). Based on thorough analysis of the fragmentation during electron ionization we developed a strategy to deduce structural information of the oxysterols. Optimized sample preparation includes (i) extraction with a mixture of n-hexane/iso-propanol, (ii) removal of cholesterol by solid phase extraction with unmodified silica, and (iii) trimethylsilylation. The method was successfully applied on the analysis of brain samples, showing consistent results with previous studies and a good intra- and interday precision of ≤20%. Finally, we used the method for the investigation of oxysterol formation during oxidative stress in HepG2 cells. Incubation with tert-butyl hydroperoxide led to a massive increase in free radical formed oxysterols (7-keto-chol > 7β-OH-chol >> 7α-OH-chol), while 24 h incubation with the glutathione peroxidase 4 inhibitor RSL3 showed no increase in oxidative stress based on the oxysterol pattern. Overall, the new method described here enables the robust analysis of a biologically meaningful pattern of oxysterols with high sensitivity and precision allowing us to gain new insights in the biological formation and role of oxysterols.     

The influence of processing route on the structuring and properties of high‐density polyethylene (HDPE)/clay nanocomposites

The effect of different processing routes on structure and properties of high‐density polyethylene (HDPE)‐clay nanocomposites was assessed. Different compatibilizer/clay ratios (α) were also studied to determine if interactions exist between processing route and polymer‐clay compatibility. HDPE/HDPE‐g‐MA/clay with α values of 1 to 4 were melt compounded (twin screw extrusion), and then processed via three routes: compression moulding, compression moulding followed by biaxial stretching or blown film extrusion. The structure was examined using X‐ray diffraction (XRD) and transmission electron microscopy (TEM). Tensile and oxygen barrier properties were determined. It was found that biaxial extensional forming produced the best enhancement in properties. An interaction between processing route and polymer‐clay compatibility is evident. Halpin‐Tsai (H‐T) model was employed to predict relative modulus values. It showed good agreement with the experimental data. For biaxial extension at α = 4.0, the experimental relative modulus is greater than the predicted value. This may indicate the existence of a “nano” effect at the polymer‐clay interface. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers     

Preparation and characterization of polyethylene/cellulose composite with diatomite and bentonite as fillers

ABSTRACT

This research work was carried out to examine the performance of different polyethylene/cellulose composites. The effect of three different factors was examined. First factor was the effect of clay type as filler, in which diatomite and bentonite were used. Second factor was the effect of cellulose grafting with cyclic oxymethylene. Third factor was the presence of polyethylene grafted with maleic anhydride (PE-g-MA) in the polymer matrix of polyethylene/cellulose as a compatibilizer. The polymer matrix was characterized by scanning electron microscope (SEM), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Tensile test and permeability were also examined.     

A review of longitudinal studies of cognitive functions in schizophrenia patients

We examined whether differences in health were associated with different probabilities of marital transitions in a longitudinal study, using Cox proportional hazard analysis. Data on approximately 10,000 Dutch persons of the GLOBE study, aged 15-74 years, were used for this purpose. The study started in 1991 and study subjects have been followed for 4.5 years. Of the four marital transitions studied (marriage among never married and divorced persons, and divorce and bereavement among married persons), only divorce among married persons was associated with health status: married persons who reported four or more subjective health complaints or two or more chronic conditions were, respectively, 1.5 and two times more likely to become divorced during follow-up than persons without these health problems. Since hardly any other studies have examined the role of health selection in marital transition with longitudinal data, more research is required before firm conclusions can be drawn. It can be concluded, however, that the frequently made assumption that health selection contributes only little to the explanation of health differences between marital status groups, seems, at least for the divorced, not justified.     

The effect of temperature and strain rate on the deformation behaviour, structure development and properties of biaxially stretched PET-clay nanocomposites

The inclusion of a synthetic fluoromica clay in PET affects its processability via biaxial stretching and stretching temperature (95 °C and 102 °C) and strain rate (1 s⁻¹ and 2 s⁻¹) influence the structuring and properties of the stretched material. The inclusion of clay has little effect on the temperature operating window for the PET-clay but it has a major effect on deformation behaviour which will necessitate the use of much higher forming forces during processing. The strain hardening behaviour of both the filled and unfilled materials is well correlated with tensile strength and tensile modulus. Increasing the stretching temperature to reduce stretching forces has a detrimental effect on clay exfoliation, mechanical and O₂ barrier properties. Increasing strain rate has a lesser effect on the strain hardening behaviour of the PET-clay compared with the pure PET and this is attributed to possible adiabatic heating in the PET-clay sample at the higher strain rate. The Halpin-Tsai model is shown to accurately predict the modulus enhancement of the PET-clay materials when a modified particle modulus rather than nominal clay modulus is used.     

De novo acute myeloid leukemia with near-pentaploidy: diploid karyotype and lymphoblastic phenotype at relapse

Hyperploidy is a rare finding in leukemias, with isolated cases of tetraploidy reported in acute myeloblastic and acute lymphblastic leukemias. We report the first case of acute myeloid leukemia with near-pentaploidy (5 n+/-) which was present in 100% of metaphases at diagnosis. By light microscopy, the leukemic blasts were exceptionally large and coarsely granulated. Following one cycle of induction chemotherapy, complete morphologic and cytogenetic remission was documented. Four weeks later relapse occured, at which time the karyotype was diploid and the morphological and immunophenotypic characteristics were those of a lymphoid leukemia. However, the presence of three aberrant chromosomes (5q+, 6q+ and 20q+) confirmed that this was clonal evolution of the original myeloid leukemia. To the best of our knowledge, this case represents the first report of near-pentaloidy in de novo, pretreatment human leukemia.     

纤维素抗菌纸的制备及性能研究

本研究设计、合成了新型季铵盐类抗菌单体(二甲基-辛基-4-乙烯基苄基氯化铵,VAC),并以纤维素纸为基质,在较为温和反应条件下,制备了具有良好性能的纤维素抗菌纸。对其进行应力-应变拉伸实验发现,当VAC添加量为5.40 g时,基于该温和反应条件制备的纤维素抗菌纸具有更好的力学性能,最大拉应力为4.04 MPa。抑菌率实验结果表明,制备的新型纤维素抗菌纸能够对大肠杆菌表现出良好的抗菌性,其抗菌率达91.40%。