Bad is a BH3 domain-containing protein that forms an inactivating dimer with Bcl-XL

The Bcl-2 related protein Bad is a promoter of apoptosis and has been shown to dimerize with the anti-apoptotic proteins Bcl-2 and Bcl-XL. Overexpression of Bad in murine FL5.12 cells demonstrated that the protein not only could abrogate the protective capacity of coexpressed Bcl-XL but could accelerate the apoptotic response to a death signal when it was expressed in the absence of exogenous Bcl-XL. Using deletion analysis, we have identified the minimal domain in the murine Bad protein that can dimerize with Bcl-xL. A 26-amino-acid peptide within this domain, which showed significant homology to the alpha-helical BH3 domains of related apoptotic proteins like Bak and Bax, was found to be necessary and sufficient to bind Bcl-xL. To determine the role of dimerization in regulating the death-promoting activity of Bad and the death-inhibiting activity of Bcl-xL, mutations within the hydrophobic BH3-binding pocket in Bcl-xL that eliminated the ability of Bcl-xL to form a heterodimer with Bad were tested for the ability to promote cell survival in the presence of Bad. Several of these mutants retained the ability to impart protection against cell death regardless of the level of coexpressed Bad protein. These results suggest that BH3-containing proteins like Bad promote cell death by binding to antiapoptotic members of the Bcl-2 family and thus inhibiting their survival promoting functions.     

Electrophysiological interactions of ethanol with GABAergic mechanisms in the rat cerebellum in vivo

Induction of neonatal H-2 tolerance is highly efficient in most allodisparate strain combinations, with the exception of those in which neonatal recipients do not, but donor cells do, express I-E molecules. For example, less than 25% of I-E-nonexpressing B10.S mice become tolerant following neonatal injection with I-E+ (B10.AxB10.S)F1 cells. It has been hypothesized that the high rate of nontolerance observed in I-E-nonexpressing neonatal recipients of injections of I-E-bearing cells is caused by a failure to delete V beta 11+ cells in the immediate postnatal period. To test this possibility, we have examined V beta 11 expression and tolerogen-responsiveness among T cells of thymus and spleens harvested periodically from B10.S mice after neonatal inoculation of (B10.AxB10.S) F1 cells. We found that V beta 11+ cells were selectively eliminated within 1-2 days from the thymus glands of all recipient mice, B10.A-specific proliferative T cells disappeared concordantly, and the thymus glands contained donor-derived chimeric cells. Subsequently, an increasing proportion of injected mice acquired V beta 11+ thymocytes and B10.A-responsive T cells, while losing chimeric cells. However, deletion and in vitro nonreactivity were still apparent in the majority of mice at 60 days of age. We conclude that neonatal inoculation of I-E-expressing cells established thymic chimerism and caused profound elimination of V beta 11+ cells from the thymus glands of all injected mice. Therefore, the failure of the majority of neonatally injected B10.S mice to display transplantation tolerance of B10.A antigens as adults cannot be ascribed to an inability to delete I-E-reactive thymocytes.     

Predicting the effects of leadership training and experience from the contingency model: Some remaining problems.

F. F. Fiedler's (see PA, Vol 52:Issue 2) clarifying remarks on using the contingency model to predict effects of leadership training and experience have resolved many of the original article's apparent inconsistencies. Some problems still remain, however, which could seriously impair the usefulness of Fiedler's recommendations. Some of these problems and some possible courses of action are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dielectric properties of BaTiO3–Bi(Zn1/2Ti1/2)O3–NaNbO3 solid solutions

In order to develop dielectric ceramics with temperature-stable permittivity characteristics, perovskite BaTiO₃–Bi(Zn_1/2Ti_1/2)O₃–NaNbO₃ ceramic solid solutions were investigated with a particular focus on effects of BaTiO₃ and NaNbO₃ contents on the dielectric properties of ternary compounds. Keeping the ratios of the other two constituents constant, decreasing the BaTiO₃ content leads to a broadening of the temperature-dependent permittivity maximum and a decrease in the overall permittivity. For compositions of constant BaTiO₃ content, replacing Bi(Zn_1/2Ti_1/2)O₃ with NaNbO₃ shifts the temperature of the maximum permittivity to lower temperatures (e.g., to ?103 °C for a composition of 70BT–5BZT–25NN) while maintaining a broad permittivity peak with temperature, which for the 50BT–25BZT–25NN composition also satisfies the X9R standard. Thus, the investigation of BT–BZT–NN compounds resulted in promising dielectric properties with broad temperature ranges of high permittivity, which is of interest for advanced capacitor applications.     

The college student as interviewer: A threat to generalizability?

A review of 6 studies which compared decision-making processes of employment interviewers and college students to examine the generalizability of research conclusions based on college student samples showed that relative to interviewers, students are lenient in their ratings. No other important differences have been reported, and findings appear to be quite comparable with respect to variances, intercorrelations, interrater agreement, and main effects for decision process, content, and accuracy. It is concluded that generalizability should never be merely assumed, but rather demonstrated empirically in other research areas, following the example of the studies involving interview decision-making. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Medical sculpture: a valuable aid to patient rehabilitation

Silicone rubber is the most satisfactory material for cosmetic prostheses. It has a soft, lifelike texture, is easily worked and easily colored and is strong enough to withstand frequent application and removal. Examples of patients referred to the medical sculptor include those with congenital defects of one or both ears, loss of the nose or an eye and orbit due to cancer surgery, loss or absence of fingers or parts of the hand and those who have had radical breast surgery.     

A test of ocean surface-current mapping with over-the-horizon radar

A two-day test with a decametric over-the-horizon (OTH or ionospheric) radar in Virginia attempted to map the radial component of ocean surface currents over a 210 000 km² area that includes the Florida Straits and parts of the Gulf of Mexico as distant as 1500 km. Ionospheric motions distort and bias individual measurements, but their effects are mitigated by a combination of strategies that take advantage of the different space and time scales of oceanic and ionospheric motions. In addition, nearby land echoes are used as zero Doppler references to correct for ionospheric shifts. The result is a composite picture of the Florida Current and ancillary surface flows with 10-15-km resolution. The picture agrees quantitatively with known currents in the region, but reveals dynamical features with new detail. Concurrent sea-surface topography in the Gulf of Mexico, derived using tandem altimetric observations from the TOPEX/Poseidon and ERS-1 satellites, confirms that a region where the OTH radar measures a southwestward current greater than 1 m/s^-1 coincides with the confluence of the Tortugas Gyre and the Gulf of Mexico Loop Current. These results suggest that consistent surface current maps can be constructed by using OTH radar to repeatedly interrogate a region of interest, perhaps over several days     

Multispectral Remote Sensing of Saline Seeps

An aircraft experiment was conducted in early summer of 1981 to determine the feasibility of optical and microwave remote sensing techniques for the detection of fully developed and incipient saline seeps in South Dakota and Montana. The NASA C-130 earth resources aircraft was used to acquire L-band and C-band scatterometer data (backscattering coefficient profiles), radiometer data (brightness temperature profiles), and color-infrared photography; additional passive microwave data and thermal images were acquired by the L- band radiometer on the Beechcraft D-18 aircraft operated by South Dakota State University. Intensive soil moisture and salinity data were collected on a uniform 20-m grid spacing and at several depths for the 600 × 600 m South Dakota site. The two Montana sites were over-flown with flight lines several kilometers in length, and ground truth information was obtained by identifying known geological and geohydrological units with varying soil salinities on a regional basis. The C-130 radiometers (both L- and C-bands) were effective in detecting wet soil areas including fully developed seeps; however, incipient seeps were not accurately detected by the radiometers. The D-18 L-band radiometer data did not appear to be sensitive to soil wetness. The C-130 scatterometer data profiles, although showing some sensitivity to soil moisture, were greatly influenced by surface roughness and appear to be ineffective in accurately delineating either fully developed or incipient seeps. Thermal-IR scanner data acquired by the D-18 aircraft did not appear to provide a reliable means for identifying potential seeps.     

Conceptual complexity as a mediator of thought content and negative affect: Implications for cognitive restructuring interventions.

Cognitive restructuring interventions assume that people are capable of recognizing their faulty thinking and can substitute adaptive cognitions to lessen negative affect and improve future appraisals of situations. The present study hypothesized that differences in conceptual complexity (CC) may mediate individuals' cognitive and emotional responses toward problem situations. 106 undergraduates high and low in CC (as measured by the Paragraph Completion Method) first imagined a neutral scene and then situations involving social rejection and academic failure, followed by assessments of attributions, self- and task statements, and change in negative affect (the Multiple Affect Adjective Check List). High-CC Ss reported more internal attributions and fewer negative task statements and showed less increases in negative mood. Although the findings have internal validity, additional research is needed before links between CC and particular cognitive/affective processes in cognitive restructuring can be determined. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)