Developmental and behavioral effects of prenatal primidone exposure in the rat

Pregnant Sprague-Dawley rats were administered primidone (PRM) by oral gavage on gestation days 8-17 in doses of 0.40, and 80 mg/kg. Although these doses of PRM did not produce significant differences in litter size, birth weight, mortality, date of attainment of developmental landmarks or measures of preweaning reflex and motor development, there were a number of significant differences that developed as the animals approached and entered adulthood. When tested as adults, the 80 mg/kg male rats showed a deficit in the performance of an eight-arm radial maze task. These same animals showed a significant reduction in open field activity when tested as adults. In addition, both male and female PRM-treated animals showed reduced body weights at different periods corresponding to onset of sexual maturation during development. These findings are consistent with the larger body of literature reporting on the neurobehavioral teratology of phenobarbital, including its ability to produce lesions in the hippocampus and endocrine dysfunction resulting in reproductive deficits. These results suggest that PRM produces its adverse effects as a result of its metabolism to phenobarbital, which in turn affects the limbic system.     

The reality of repressed memories.

Repression is one of the most haunting concepts in psychology. Something shocking happens, and the mind pushes it into some inaccessible corner of the unconscious. Later, the memory may emerge into consciousness. Repression is one of the foundation stones on which the structure of psychoanalysis rests. Recently there has been a rise in reported memories of childhood sexual abuse that were allegedly repressed for many years. With recent changes in legislation, people with recently unearthed memories are suing alleged perpetrators for events that happened 20, 30, even 40 or more years earlier. These new developments give rise to a number of questions: (1) How common is it for memories of child abuse to be repressed? (2) How are jurors and judges likely to react to these repressed memory claims? (3) When the memories surface, what are they like? and (4) How authentic are the memories? (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gastroparesis after celiac plexus block

Pectin constituents, which were about 70 w/w% of extracellular polysaccharides (ECP) from a cell-suspension culture of Mentha, were purified by gel filtration chromatography, and their sugar composition and linkage were investigated. Two major constituents identified were (1-->3)-linked galactan carrying arabinosyl residues on C-6 and (1-->4)-alpha-linked galacturonan partially interspersed with (1-->2)-linked rhamnosyl resides. Acetylated or methylated pectins were not identified on 1H-NMR analysis.     

Insulin depletion leads to adipose-specific cell death in obese but not lean mice

Mutation of the obese gene produces obesity, hyperinsulinemia, and compensatory "overexpression" of the defective gene. As insulin activates obese gene expression, it seemed possible that hyperinsulinemia might be responsible for overexpression of the gene. To address this question we rapidly neutralized circulating insulin by injection of an insulin antibody. Unexpectedly, insulin depletion in obese (ob/ob or db/db) mice caused massive adipose RNA degradation confirmed by histological analysis to result from adipocyte cell death by a largely necrotic mechanism. This effect was not observed in lean littermates and was completely corrected by coadministration of insulin. Comparison of multiple tissues demonstrated that the effect was restricted to adipose tissue. Insulin depletion in obese mice by administration of streptozotocin also led to cell death, but this death was less extensive and appeared to be apoptotic in mechanism. Thus insulin may promote the survival side of the physiological balance between adipocyte survival and death.     

Detecting palindromes,patterns and borders in regular languages

Given a language L and a non-deterministic finite automaton M, we consider whether we can determine efficiently (in the size of M) if M accepts at least one word in L, or infinitely many words. Given that M accepts at least one word in L, we consider how long a shortest word can be. The languages L that we examine include the palindromes, the non-palindromes, the k-powers, the non-k-powers, the powers, the non-powers (also called primitive words), the words matching a general pattern, the bordered words, and the unbordered words.     

Wall and ceiling protection for heating appliances

An evaluation was made of the effects of radiant heat transfer from hot stove and chimney pipes to unprotected and protected room walls and ceilings. Pipe surface temperatures were 350° C (662° F) for normal operation, and 400–450° C (752–842° F) to simulate overfire conditions. Unprotected ceilings at 457 mm (18 in.) clearance met code recommended temperature rise limits for normal operation, but protection was needed for overfire exposures. Some protected walls allowed for clearance reductions to 76 mm (3 in.) for all exposures, while others needed at least 304 mm (12 in.) for normal and 457 mm (18 in.) for overfire exposures.Recommendations for model building code specifications for wall and ceiling protection are provided. Reference: Joseph J. Loftus and Richard D. Peacock, Wall and Ceiling Protection for Heating Appliances,Fire Technology, Vol. 21, No. 3, August 1985, p. 213.This paper is a contribution of the National Bureau of Standards and is not subject to copyright.     

Treasure of the Past IX: Exposure Standardization of Iodine-125 Seeds Used for Brachytherapy

A method for calibrating iodine-125 seeds in terms of exposure has been established. The standard free-air ionization chamber, used for measuring soft x rays, was chosen for the measurements. Arrays of four to six seeds were used to enhance the ionization-current-to-background-current ratio. Seeds from an array were measured individually in a re-entrant chamber. The quotient of the exposure rate for the array by the sum of the ionization currents in the re-entrant chamber is the calibration factor for the re-entrant chamber. Calibration factors were established for three types of iodine-125 seeds. The overall uncertainty for the seed exposure calibrations is less than 6%.     

Dream interpretation can change beliefs about the past.

Forty-six nonclinical subjects reported on their childhood experiences on two occasions, separated by 3–4 weeks. between these sessions, some subjects were exposed to a 30-min therapy simulation in which their dream material was analyzed by a clinical psychologist. He suggested to subjects that their dreams were indicative of having experienced, before the age of three, certain critical experiences (e.g., being lost in a public place or feeling abandoned by parents). Subjects previously reported that these critical events had not occurred. The brief therapy simulation led them to dramatic shifts in belief that the experiences had occurred. These results show that brief therapy-like interactions can change people's beliefs about the past, and have implications for the power of clinical intervention. Dream interpretation, commonly practiced in psychotherapy to guide patient's understanding of themselves, may have unexpected side effects if it leads to beliefs about the past that may in fact be false. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Use of exemplars and abstractions in trait judgments: A model of trait knowledge about the self and others.

According to pure exemplar models, trait judgments about the self and others are accomplished by retrieving from memory trait-exemplifying behaviors and computing the similarity between the trait and the exemplars retrieved. By contrast, pure abstraction models argue that trait judgments are made by directly accessing abstract, summary knowledge of the person's traits. In a series of 4 studies, the role of behavioral exemplars and abstract trait knowledge in trait judgments about others and about the self was examined. The findings show that both types of information are used to make trait judgments but that the relative importance of each type is determined by the amount of trait-exemplifying behavioral experience one has with the person being judged. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Substantial narrowing of the Niemann-Pick C candidate interval by yeast artificial chromosome complementation

Niemann-Pick disease type C (NP-C) is an autosomal recessive lipidosis linked to chromosome 18q11-12, characterized by lysosomal accumulation of unesterified cholesterol and delayed induction of cholesterol-mediated homeostatic responses. This cellular phenotype is identifiable cytologically by filipin staining and biochemically by measurement of low-density lipoprotein-derived cholesterol esterification. The mutant Chinese hamster ovary cell line (CT60), which displays the NP-C cellular phenotype, was used as the recipient for a complementation assay after somatic cell fusions with normal and NP-C murine cells suggested that this Chinese hamster ovary cell line carries an alteration(s) in the hamster homolog(s) of NP-C. To narrow rapidly the candidate interval for NP-C, three overlapping yeast artificial chromosomes (YACs) spanning the 1 centimorgan human NP-C interval were introduced stably into CT60 cells and analyzed for correction of the cellular phenotype. Only YAC 911D5 complemented the NP-C phenotype, as evidenced by cytological and biochemical analyses, whereas no complementation was obtained from the other two YACs within the interval or from a YAC derived from chromosome 7. Fluorescent in situ hybridization indicated that YAC 911D5 was integrated at a single site per CT60 genome. These data substantially narrow the NP-C critical interval and should greatly simplify the identification of the gene responsible in mouse and man. This is the first demonstration of YAC complementation as a valuable adjunct strategy for positional cloning of a human gene.