2,525 research outputs found

    P53 mutations in human adrenocortical neoplasms

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    The mechanisms of tumorigenesis of adrenocortical neoplasms have not been elucidated as yet. However, loss of heterozygosity at chromosomal locus 17p has been consistently observed in adrenocortical cancer. p53 is a recessive tumor suppressor gene located on chromosome 17p. Mutations in the p53 gene play an important role in the tumorigenesis of diverse types of human neoplasms including breast and colon cancers. More than 90% of all mutations discovered in such tumors have been detected in 4 hot spot areas that lie between exons 5 and 8. In contrast to wild-type p53, mutant p53 accumulates intracellularly and can be easily detected by immunohistochemistry. We therefore investigated the frequency of p53 mutations in human adrenocortical neoplasms using molecular biology and immunohistochemistry techniques. Five patients with adrenocortical adenomas (5 female; ages 39-72 yr), 11 patients with adrenocortical carcinomas (8 female, 3 male; ages 15- 50 yr), and two adrenocortical tumor cell lines were studied. After DNA extraction from frozen tumor tissue or paraffin-embedded material, exons 5 through 8 were amplified using the polymerase chain reaction and directly sequenced by the dideoxy termination method. Immunohistochemistry was performed on paraffin-embedded tumor specimens obtained during adrenalectomy using a monoclonal antibody reacting with both wild-type and mutant p53. Prevalence of mutations was adenomas, 0/5, carcinomas, 3/11, and adrenocortical cell lines, 2/2. Single point mutations were detected in 3 cases (exons 5, 6, and 7, respectively), and rearrangements of exon 7/8 and 8 were found in 2 cases. Immunohistochemistry detected strong nuclear and/or cytoplasmic p53 immunoreactivity in all adrenocortical carcinomas with point mutations of the p53 gene but not in adenomas and carcinomas with the wild-type sequence or with deletion/rearrangement of the p53 gene. We conclude that p53 plays a role in the tumorigenesis of adrenocortical carcinomas but is of less importance to benign adenomas

    Early stages of ramified growth in quasi-two-dimensional electrochemical deposition

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    I have measured the early stages of the growth of branched metal aggregates formed by electrochemical deposition in very thin layers. The growth rate of spatial Fourier modes is described qualitatively by the results of a linear stability analysis [D.P. Barkey, R.H. Muller, and C.W. Tobias, J. Electrochem. Soc. {\bf 136}, 2207 (1989)]. The maximum growth rate is proportional to (I/c)δ(I/c)^\delta where II is the current through the electrochemical cell, cc the electrolyte concentration, and δ=1.37±0.08\delta = 1.37 \pm 0.08. Differences between my results and the theoretical predictions suggest that electroconvection in the electrolyte has a large influence on the instability leading to ramified growth.Comment: REVTeX, four ps figure

    Changes in Trauma-related Emotions Following Treatment with Dialectical Behavior Therapy for Posttraumatic Stress Disorder after Childhood Abuse

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    Dialectical behavior therapy for posttraumatic stress disorder (DBT-PTSD) is a trauma-focused therapy shown to reduce core PTSD symptoms, such as intrusions, hyperarousal, and avoidance. Preliminary data indicate effects on elevated trauma-related emotions (e.g., guilt and shame) and possibly radical acceptance of the traumatic event. However, it is unclear if improvements in these variables are significant after controlling for changes in core PTSD symptoms and to what extent nonclinical levels are obtained. In the current study, 42 individuals who met criteria for PTSD after childhood abuse and were participating in a 3-month residential DBT-PTSD program were evaluated at the start of the exposure phase of DBT-PTSD and the end of treatment; a nonclinical sample with a history of childhood abuse was the reference group. Multivariate analyses of variance and multivariate analyses of covariance controlling for change in core PTSD symptoms were used to evaluate changes in several elevated trauma-related emotions (fear, anger, guilt, shame, disgust, sadness, and helplessness) and in radical acceptance. In a repeated measures multivariate analyses of variance, both elevated trauma-related emotions and radical acceptance significantly improved during DBT-PTSD, λ = 0.34, p &lt;.001; η 2 =.56; t(40) = −5.66, p &lt;.001, SMD = 0.88, even after controlling for changes in PTSD symptoms, λ = 0.35, p &lt;.001, η 2 =.65; Λ = 0.86, p =.018, η 2 =.14, respectively. Posttreatment, 31.0% (for acceptance) to 76.2% (for guilt) of participants showed nonclinical levels of the investigated outcomes, suggesting that both trauma-related emotions and radical acceptance changed after the 3-month residential DBT-PTSD program. </p

    The grinch who stole wisdom

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    Dr. Seuss is wise. How the Grinch Stole Christmas (Seuss, 1957) could serve as a parable for our time. It can also be seen as a roadmap for the development of contemplative wisdom. The abiding popularity of How the Grinch Stole Christmas additionally suggests that contemplative wisdom is more readily available to ordinary people, even children, than is normally thought. This matters because from the point of view of contemplatives in any of the world's philosophies or religions, people are confused about wisdom. The content of the nascent field of wisdom studies, they might say, is largely not wisdom at all but rather what it's like to live in a particular kind of prison cell, a well appointed cell perhaps, but not a place that makes possible either personal satisfaction or deep problem solving. I believe that what the contemplative traditions have to say is important; they offer a different orientation to what personal wisdom is, how to develop it, and how to use it in the world than is presently contained in either our popular culture or our sciences. In order to illustrate this I will examine, in some detail, one contemplative path within Buddhism. Buddhism is particularly useful in this respect because its practices are nontheistic and thus avoid many of the cultural landmines associated with the contemplative aspects of Western religions

    Identification of Radiopure Titanium for the LZ Dark Matter Experiment and Future Rare Event Searches

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    The LUX-ZEPLIN (LZ) experiment will search for dark matter particle interactions with a detector containing a total of 10 tonnes of liquid xenon within a double-vessel cryostat. The large mass and proximity of the cryostat to the active detector volume demand the use of material with extremely low intrinsic radioactivity. We report on the radioassay campaign conducted to identify suitable metals, the determination of factors limiting radiopure production, and the selection of titanium for construction of the LZ cryostat and other detector components. This titanium has been measured with activities of 238^{238}Ue_{e}~<<1.6~mBq/kg, 238^{238}Ul_{l}~<<0.09~mBq/kg, 232^{232}The_{e}~=0.28±0.03=0.28\pm 0.03~mBq/kg, 232^{232}Thl_{l}~=0.25±0.02=0.25\pm 0.02~mBq/kg, 40^{40}K~<<0.54~mBq/kg, and 60^{60}Co~<<0.02~mBq/kg (68\% CL). Such low intrinsic activities, which are some of the lowest ever reported for titanium, enable its use for future dark matter and other rare event searches. Monte Carlo simulations have been performed to assess the expected background contribution from the LZ cryostat with this radioactivity. In 1,000 days of WIMP search exposure of a 5.6-tonne fiducial mass, the cryostat will contribute only a mean background of 0.160±0.0010.160\pm0.001(stat)±0.030\pm0.030(sys) counts.Comment: 13 pages, 3 figures, accepted for publication in Astroparticle Physic
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