Effect of interferon γ on the sensitivity of bovine-papilloma-virus(BPV1)-transformed cell lines to cell-mediated cytotoxicity

Summary The effect of interferon (IFN) on the immunogenicity and immunosensitivity of mouse cell lines transformed by bovine papillomavirus type 1 (BPV1) DNA was examined in a syngeneic mouse model. The overnight incubation of BPV1-transformed cell lines with 100 IU/ml IFN did not affect their ability to induce the generation of cytotoxic effector cells but it clearly increased their sensitivity to lysis by interleukin-2-induced lymphokine-activated killer (LAK) cells and by nonspecific LAK-type effector cells induced by BPV-1-transformed cell lines. The treatment of two allogeneic lymphoid tumour cell lines, P815X2 and YAC-1, with IFN either decreased or had no effect on their sensitivity to LAK-cell-mediated lysis.     

SOD3 decreases ischemic injury derived apoptosis through phosphorylation of Erk1/2, Akt, and FoxO3a

Background

Extracellular superoxide dismutase (SOD3), which dismutates superoxide anion to hydrogen peroxide, has been shown to reduce the free radical stress derived apoptosis in tissue injuries. Since both superoxide anion and hydrogen peroxide have a marked impact on signal transduction pathways and could potentially explain a number of apoptosis and survival -related phenomena in different pathological conditions, we clarified the impact of SOD3 on Akt and Erk1/2 cell survival pathways in rat hind limb injury model.

Methodology and Principal Findings

Based on our data, the hind limb ischemic rats treated with virally delivered sod3 have milder injury and less apoptosis than control animals that could be due to parallel activation of pro-proliferative and anti-apoptotic Erk1/2 and Akt pathways. The common downstream factor of both signaling pathways, the apoptosis related forkhead box protein O3a (FoxO3a), was phosphorylated and translocated to the cytoplasm in sod3 treated tissues and cell line. Additionally, we obtained increased mRNA production of elk-1, ets-1, and microRNA 21 (miR-21), whereas synthesis of bim mRNA was decreased in sod3 overexpressing tissues. We further showed that overexpression of sod3 modulated redox related gene expression by downregulating nox2 and inos when compared to injured control animals.

Conclusions and Significance

The study shows the complexity of SOD3-derived effects on tissue injury recovery that are not limited to the reduction of superoxide anion caused cellular stress but highlights the impact of SOD3 related signal transduction on tissue functions and suggests an important role for SOD3 in attenuating cell stress effects in different pathological conditions.     

Combining NMR ensembles and molecular dynamics simulations provides more realistic models of protein structures in solution and leads to better chemical shift prediction

While chemical shifts are invaluable for obtaining structural information from proteins, they also offer one of the rare ways to obtain information about protein dynamics. A necessary tool in transforming chemical shifts into structural and dynamic information is chemical shift prediction. In our previous work we developed a method for 4D prediction of protein ¹H chemical shifts in which molecular motions, the 4th dimension, were modeled using molecular dynamics (MD) simulations. Although the approach clearly improved the prediction, the X-ray structures and single NMR conformers used in the model cannot be considered fully realistic models of protein in solution. In this work, NMR ensembles (NMRE) were used to expand the conformational space of proteins (e.g. side chains, flexible loops, termini), followed by MD simulations for each conformer to map the local fluctuations. Compared with the non-dynamic model, the NMRE+MD model gave 6–17% lower root-mean-square (RMS) errors for different backbone nuclei. The improved prediction indicates that NMR ensembles with MD simulations can be used to obtain a more realistic picture of protein structures in solutions and moreover underlines the importance of short and long time-scale dynamics for the prediction. The RMS errors of the NMRE+MD model were 0.24, 0.43, 0.98, 1.03, 1.16 and 2.39 ppm for ¹Hα, ¹HN, ¹³Cα, ¹³Cβ, ¹³CO and backbone ¹⁵N chemical shifts, respectively. The model is implemented in the prediction program 4DSPOT, available at .     

Isolation and Identification of Aspergillus fumigatus Mycotoxins on Growth Medium and Some Building Materials

Genotoxic and cytotoxic compounds were isolated and purified from the culture medium of an indoor air mold, Aspergillus fumigatus. One of these compounds was identified as gliotoxin, a known fungal secondary metabolite. Growth of A. fumigatus and gliotoxin production on some building materials were also studied. Strong growth of the mold and the presence of gliotoxin were detected on spruce wood, gypsum board, and chipboard under saturation conditions.     

Substrate specificity and reaction mechanism of human glycoasparaginase. The N-glycosidic linkage of various glycoasparagines is cleaved through a reaction mechanism similar to L-asparaginase.

Human glycoasparaginase (N4-(beta-N-acetyl-D-glucosaminyl)-L-asparaginase, EC 3.5.1.26) hydrolyzes a series of compounds that contain L-asparagine residue with free alpha-amino and alpha-carboxyl groups. Substrates include high mannose and complex type glycoasparagines as well as those that lack the di-N-acetylchitobiose moiety, L-aspartic acid beta-methyl ester and L-aspartic acid beta-hydroxamate. The enzyme is inactive toward L-asparagine and L-glutamine and glycoasparagines containing substituted alpha-amino and/or alpha-carboxyl groups. In the presence of the acyl acceptor hydroxylamine, glycoasparaginase catalyzes the synthesis of L-aspartic acid beta-hydroxamate from aspartyl-glucosamine, L-aspartic acid beta-methyl ester, and L-aspartic acid. 13C NMR studies using 18O-labeled L-aspartic acid demonstrate that glycoasparaginase catalyzes an oxygen exchange between water and the carboxyl group at C-4 of L-aspartic acid. These results indicate that glycoasparaginase reacts as an exo-hydrolase toward the L-asparagine moiety of the substrates and the free alpha-amino and alpha-carboxyl groups are required for the enzyme reaction. The results are consistent with an L-asparaginase-like reaction pathway which involves a beta-aspartyl enzyme intermediate. Since glycoasparaginase is active toward a series of structurally different glycoasparagines, we suggest the revised systematic name of N4-(beta-glycosyl)-L-asparaginase for the enzyme.     

Determination of estriol, estriol sulfate, progesterone and neutral steroid mono- and disulfates in umbilical cord blood plasma

Fractions of unconjugated steroids, and steroid mono- and disulfates were isolated from cord plasma, and the concentrations of estriol, estriol sulfate, progesterone, 13 neutral steroid monosulfates (MoS) and 10 neutral steroid disulfates (DiS) were determined by gas-liquid chromatography. The mean concentrations in 30 cord plasma samples at term after normal pregnancy and delivery were as follows (μg/100 ml of free steroid ±standard deviation): estriol 16±5; estriol monosulfate 135±43; progesterone 59±19; dehydroepiandrosterone MoS 76±23; 5-androstene-3_β,17_α-diol DiS 279±77; 5-androstene-3_β,17_β-diol DiS 211±109; 16_α-hydroxydehydroepiandrosterone MoS 305±97; 16_β-hydroxy-dehydroepiandrosterone DiS 8±25; 33,17_β-dihydroxy-5-androsten-16-one MoS 37±16, DiS 29±15 5-androstene-3_β,16_α,17_β-triol MoS 25±9; 5-androstene-3_β,16_β,17_α-triol DiS 31±14; pregnenolone MoS 4±33; 5-pregnene-3_β,20_α-diol MoS 41±14, DiS 68±43; 16_α-hydroxypregnenolone MoS 101±42; 17-hydroxypregnenolone MoS 56±30; 21-hydroxypregnenolone DiS 26±15; 5-pregnene-3_β,20_α,21-triol MoS 37±18; 5_α-pregnane-3_α,20_α-diol MoS 21±10, DiS 54±21; 5_α-pregnane-3_β,20_α-diol MoS 18±9, DiS 7±39; 5_β-pregnane-3_α,20_α-diol MoS 17±7; 5_α-pregnane-3_α,20_α,21-triol MoS 110±56, DiS 22±19.The total amount of steroid monosulfates in the cord plasma pool was 1 mg/100 ml and that of steroid disulfates 0.5 mg/100 ml. 3_β-Hydroxy-Δ⁵-steroids predominated. Considerable amounts of saturated c₂₁ steroids were also detected. No statistically significant differences were found in the concentrations of any of the steroids studied, when a group of male and female fetuses were compared.     

Relation of chronotype to sleep complaints in the general Finnish population

Individuals show variation in their preference for the daily timing of activities. In this study the authors analyzed whether chronotypes associate with sleep duration and sleep-related complaints. The authors used the National FINRISK Study 2007 Survey data on 3696 women and 3162 men, representative of the Finnish population aged 25 yrs and older, for the assessment of chronotype and self-reported sleep. Evening types experienced insomnia symptoms, had nightmares, and had used recently hypnotics significantly more often than other chronotypes among both men and women. In a multinominal logistic regression model predicting insufficient sleep, the association of eveningness with insufficient sleep was not abolished after adjustment for sex, age, and sleep duration. The prevalence of short sleepers was significantly higher in evening types among men than among women, whereas that of long sleepers was significantly higher in evening types among both men and women, as compared with the other chronotypes. These results indicate that eveningness predisposes individuals to a range of sleep complaints.