What neuroimaging and brain localization can do, cannot do and should not do for social psychology.

Interest in bridging social psychology and neuroscience has seen a significant upsurge. Much of this interest has centered on brain localization--the attempt to relate psychological events to locations of brain events. Although many articles have sought to localize brain activity that supports social behavior, scant attention has been paid to the specific methods to be used in integrating brain localization data into psychological theory. The authors describe 4 strategies psychologists can use to integrate brain localization data and psychological theory, and they consider whether social psychology presents special considerations in the use of these strategies. They conclude that brain localization offers a useful tool for some but not all problems in social psychology, and they discuss the types of problems for which it may and may not prove useful. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Establishment and molecular characterization of five cell lines derived from renal and extrarenal malignant rhabdoid tumors

Malignant rhabdoid tumor (MRT) is a rare, enigmatic childhood cancer characterized by extreme aggressiveness and resistance to chemotherapy. To understand better the origin of the tumor and the mechanisms by which it develops and resists treatment, five cell lines were established from patients presenting with MRT (two renal and three extrarenal tumors). All of the cell lines display the light microscopic and ultrastructural features, as well as the variable immunohistochemical profile, characteristic of MRT. All are capable of forming tumors in nude mice. Three of the cell lines have detectable abnormalities of chromosome 22: one a t(22, 22) unbalanced translocation and two others a loss of heterozygosity of polymerase chain reaction-based microsatellite markers. Northern blot analysis showed that overexpression of the c-myc message was a consistent characteristic of the five MRTs evaluated. Although mutations of the p53 gene were not detectable by sequence analysis, all of the cell lines showed nuclear accumulation of the p53 protein by an immunocytochemical analysis in a minority of the cells. This result suggests that dysfunction in a p53-dependent apoptotic pathway might play a role in the multiple drug resistance phenotype of these tumors.     

A BiCMOS low-distortion 8-MHz low-pass filter

An 8-MHz seventh-degree elliptic-function low-pass filter is described, demonstrating an approach to low-distortion antialias filtering for high-definition video applications. The filter's performance goals are achieved through the use of circuit design principles that capitalize on the strengths of BiCMOS technology. The integrator circuits composing the filter consist of a new wideband low-distortion transconductor circuit and a unique BiCMOS Miller-stage circuit. Integrator time constants are determined by stable RC products, enabling a simplified filter calibration scheme that is insensitive to temperature-induced variations and requires no phaselock circuits. The prototype filter IC, consisting of seven integrators assembled in an active-ladder configuration, was fabricated in a 10-V, 2-μm 2.5-GHz BiCMOS technology that also features thin-film resistors and polysilicon-plate capacitors. Measured results from the calibrated filter show passband flatness of 0.2 dB, with aberrations of less than ±1 dB over a 100°C temperature range. Stopband attenuation meets its designed goal of 60 dB. Driven by 7-V_pp, differential input signals, the filter exhibits less than -72-dBc third-order intermodulation distortion products at 1 MHz. For 5-V_pp inputs at 4 MHz, third-order intermodulation spurs remain below -65 dBc     

Radioprotectant Activity of Dicopper(II) Tetrakis(3,5- Diisopropylsalicylate) and Manganese(II) bis(3,5- Diisopropylsalicylate) Alone and in Combination

Dicopper(ll) tetrakis(3,5-diisopropylsalicylate), (Cu(II)(2)(3,5-DIPS)(4), manganese(II) bis(3,5-diisopropylsalicylate), Mn(II)3,5-DIPS)(2) or combinations of them were used to treat gamma-irradIated mice in examining the possibility that combination treatments might be more effective in increasing survival than treatment with either complex alone. Doses of 0, 10, 20, or 40 mumol of each complex per kilogram of body mass were administered subcutaneously in a factorial design before 9 Gy gamna irradiation, an LD(90) dose of irradiation. Doses of 0, 10, 20, or 40 mumol Cu(II)(2)(3, 5-DIPS)(4) per kg of body mass produced 12, 28, 28, or 36 % survival, respectively, while doses of 0, 10, 20, or 40 mumol (II)(3), 5-DIPS)(2) per kg of body mass prduced 12, 36, 20, or 24 % survival, respectively. However, the combination of 20 mumol Cu(II)(2)(3, 5-DIPS)(4) and 10 mumol Mn(II)(3, 5-DIPS)(2) produced the greatest survival, 48 %, which was 300 % greater than vehicle-treated mice (P=0.01). It is concluded that specific combination treatments can be used to maximize survival of lethally irradiated mice.     

Neurobiological and memory models of risky decision making in adolescents versus young adults.

Predictions of fuzzy-trace theory and neurobiological approaches are examined regarding risk taking in a classic decision-making task—the framing task—as well as in the context of real-life risk taking. We report the 1st study of framing effects in adolescents versus adults, varying risk and reward, and relate choices to individual differences, sexual behavior, and behavioral intentions. As predicted by fuzzy-trace theory, adolescents modulated risk taking according to risk and reward. Adults showed standard framing, reflecting greater emphasis on gist-based (qualitative) reasoning, but adolescents displayed reverse framing when potential gains for risk taking were high, reflecting greater emphasis on verbatim-based (quantitative) reasoning. Reverse framing signals a different way of thinking compared with standard framing (reverse framing also differs from simply choosing the risky option). Measures of verbatim- and gist-based reasoning about risk, sensation seeking, behavioral activation, and inhibition were used to extract dimensions of risk proneness: Sensation seeking increased and then decreased, whereas inhibition increased from early adolescence to young adulthood, predicted by neurobiological theories. Two additional dimensions, verbatim- and gist-based reasoning about risk, loaded separately and predicted unique variance in risk taking. Importantly, framing responses predicted real-life risk taking. Reasoning was the most consistent predictor of real-life risk taking: (a) Intentions to have sex, sexual behavior, and number of partners decreased when gist-based reasoning was triggered by retrieval cues in questions about perceived risk, whereas (b) intentions to have sex and number of partners increased when verbatim-based reasoning was triggered by different retrieval cues in questions about perceived risk. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

5-Fluorouracil interferes with paclitaxel cytotoxicity against human solid tumor cells

Paclitaxel, a naturally occurring antimitotic agent, has shown efficacy in the treatment of certain solid tumors, particularly metastatic breast carcinoma and drug-refractory ovarian cancers. Recent studies have demonstrated that paclitaxel, in addition to its effects on microtubules and cell cycle arrest, possesses significant cell-killing activity in solid tumor cells by the induction of apoptosis. However, the mechanism by which paclitaxel leads to cell death and its relationship with paclitaxel-induced mitotic arrest is presently unclear. In this study, we attempted to determine whether pre-arresting tumor cells at other phases of the cell cycle could affect paclitaxel-induced apoptosis. We found that 5-fluorouracil (5-FU), another antineoplastic agent that usually arrests tumor cells at the G1-S phase of the cell cycle, could significantly repress the cell-killing activity of paclitaxel in solid tumor cells, even when it was added simultaneously with paclitaxel. Further studies indicated that 5-FU actually inhibits the cytotoxic effects of paclitaxel on both mitotic arrest and apoptotic cell death, suggesting that 5-FU might interfere with paclitaxel cytotoxicity at an early stage, probably by preventing tumor cells from entering G2-M phase. Because recent clinical trials have used a combination of paclitaxel and 5-FU in the treatment of metastatic breast cancers, our results also suggest that the combination of these two drugs might not be as valuable in clinical chemotherapy.     

Ricin toxin contains three lectin sites which contribute to its in vivo toxicity

Ricin intoxication of mammalian cells is initiated by B chain (RTB) binding to cell surface galactosides. Recombinant insect-derived RTB mutants with modifications in lectin-site subdomains 2 gamma, 1 alpha/2 gamma, and 1 alpha/1 beta/2 gamma were reassociated with plant RTA and tested for lethality in C57B1/6 6-8 weeks old mice. The LD50 of intraperitoneally injected castor bean ricin was 75 ng per 18 g mouse. The LD50 of single-site 2 gamma mutant heterodimer was 100 ng: the LD50 of the double-site 1 alpha/2 gamma mutant heterodimer was 500 ng, and the LD50 of the triple-site 1 alpha/1 beta,2 gamma mutant heterodimer was > 10 micrograms. Plant RTA alone had an LD50 of 300 micrograms. Animals died between 1 and 10 days post-injection. Histopathological examination of morbid animals receiving an LD50 dose of each toxin revealed only apoptosis in the thymus and spleen. The present data provide clear evidence for participation of three lectin sites in ricin in vivo toxicity. These results suggest an origin for some of the normal tissue toxicities observed with clinical trials of doubly blocked ricin conjugates and suggest modification of at least three RTB subdomains will be necessary in genetically engineered ricin fusion proteins.     

Long-Term Tritium Transport through Field-Scale Compacted Soil Liner

A 13-year study of tritium transport through a field-scale earthen liner was conducted by the Illinois State Geological Survey to determine the long-term performance of compacted soil liners in limiting chemical transport. Two field-sampling procedures (pressure-vacuum lysimeter and core sampling) were used to determine the vertical tritium concentration profiles at different times and locations within the liner. Profiles determined by the two methods were similar and consistent. Analyses of the concentration profiles showed that the tritium concentration was relatively uniformly distributed horizontally at each sampling depth within the liner and thus there was no apparent preferential transport. A simple one-dimensional analytical solution to the advective–dispersive solute transport equation was used to model tritium transport through the liner. Modeling results showed that diffusion was the dominant contaminant transport mechanism. The measured tritium concentration profiles were accurately modeled with an effective diffusion coefficient of 6×10?4?mm2/s, which is in the middle of the range of values reported in the literature.     

Body composition of lambs receiving 30 or 60 days of exercise training and (or) fenoterol treatment

The interaction between exercise and the β-adrenergic agonist, fenoterol, on body composition and muscle protein turnover was studied in this investigation. Forty young Hampshire×Rambouillet lambs were assigned to control (CON), exercised (EX), fenoterol-treated (5 ppm) (FEN), or fenoterol-treated and exercised (FENEX) groups. Lambs assigned to the exercise treatments were trained to run on a 10° inclined treadmill. The lambs were slaughtered after 30 or 60 days of treatment. Average daily gain tended (p=0.09) to be greater, and feed:gain was significantly lower (p=0.03) in the EX group than in the FENEX group by 30 days of treatment. By 60 days of treatment, kidney and pelvic fat and bodywall thickness were least in the EX group. Leg weights increased significantly with time only in the FEN and FENEX groups, whereas shoulder weights increased with time in all but the EX group. The latter effect was due to a cessation of adipose tissue growth in the EX lambs. There were significant time×treatment effects for the M. biceps femoris, M. gluteus medius, M. quadriceps femoris, M. semimembranosus, M. semitendinosus, M. infraspinatus, and M. pectoralis profundus. In every case, the time×treatment interaction was caused by nonsignificant growth of muscles in the CON group between 30 and 60 days. For the M. biceps femoris, M. quadriceps femoris, and M. gluteus medius, muscle mass increased with time only in the FENEX lambs. There was no increase in leg subcutaneous or intermuscular adipose tissue mass between 30 and 60 days in the EX lambs, although 50-70% increases in adipose tissue mass were observed over time in the other groups. Calpain and calpastatin activities in M. biceps femoris were not affected by treadmill exercise, fenoterol administration, or time×treatment (p>0.72 for all effects). Myosin light chain-1 gene expression in the FENEX lambs was depressed by 60 d, suggesting that the rate of M. biceps femoris growth in this treatment group was slowing by this time.