Association of GNB3 C825T polymorphism with peak oxygen consumption.

The C825T single nucleotide polymorphism (SNP) in the guanine nucleotide-binding protein, beta polypeptide 3 ( GNB3) gene gives rise to a splice variant, GNB3s that has enhanced G protein activation and signal transduction activity. This variant has been reported to be associated with cardiovascular disease, diabetes and obesity. We studied this SNP in 95 healthy 18 to 30 year-old African American university students to determine its association with aerobic capacity and cardiorespiratory fitness as measured by peak oxygen consumption (VO (2)peak). We also tested the effect of heart rate variability (HRV) as an independent predictor of VO (2)peak. We tested the association of the SNP and HRV with VO (2)peak in a multivariate regression analysis with appropriate adjustments of covariates, under dominant and recessive models. We found a significant independent association of the 825T allele with VO (2)peak under the dominant model (beta-coef.=-0.101, P=0.0442). We also observed that HRV marginally influenced VO (2)peak. This finding suggests that GNB3 C825T polymorphism is associated with VO (2)peak which is influenced by autonomic modulation of heart rate in African Americans.

Routine childhood immunizations.

The immunizations recommended in the 2001 Childhood Immunization Schedule are safe and effective. Newly approved vaccines, like the pneumococcal conjugate vaccine, hold the promise of eliminating or dramatically reducing persistent causes of childhood morbidity and mortality in the United States.

Myelitis and ascending flaccid paralysis due to congenital toxoplasmosis.

A 4-week-old female newborn developed ascending flaccid paralysis and radiologic evidence of myelitis; the diagnosis of congenital toxoplasmosis was confirmed by the presence of Toxoplasma gondii-specific immunoglobulins in both mother and infant, and detection of Toxoplasma sequences in the infant's cerebrospinal fluid by polymerase chain reaction analysis. Treatment with pyrimethamine, sulfadiazine, and methylprednisolone resulted in improvement.

Verbal pragmatics following unilateral stroke: emotional content and valence.

Verbal pragmatic aspects of discourse production were examined in 16 right brain-damaged (RBD), 16 left brain-damaged (LBD), and 16 normal control right-handed adults. The facilitation effect of emotional content, valence hypothesis, and relationship between pragmatics and emotion were evaluated. Participants produced monologues while recollecting emotional and nonemotional experiences. Transcribed monologues were rated for appropriateness on 6 pragmatic features: conciseness, lexical selection, quantity, relevancy, specificity, and topic maintenance. Overall, brain-damaged groups were rated as significantly less appropriate than normals. Consistent with the facilitation effect, emotional content enhanced pragmatic performance of LBD aphasic participants yet suppressed performance of RBD participants. Contrary to the valence hypothesis, RBD participants were more impaired for positive emotions and LBD participants for negative emotions. Pragmatic appropriateness was not strongly correlated with a measure of emotional intensity.

Factors affecting young children's use of pronouns as referring expressions.

Most studies of children's use of pronouns have focused either on the morphology of personal pronouns or on the anaphoric use of pronouns by older children. The current two studies investigated factors affecting children's choice of pronouns as referring expressions-in contrast with their use of full nouns and null references. In the first study it was found that 2.5- and 3.5-year-old children did not use pronouns differentially whether the adult (a) modeled a pronoun or a noun for the target object or (b) did or did not witness the target event (although there was evidence that they did notice and take account of the adult's witnessing in other ways). In the second study it was found that children of this same age (a) do not use pronouns to avoid unfamiliar or difficult nouns but (b) do use pronouns differently depending on the immediately preceding discourse of the experimenter (whether they were asked a specific question such as "What did X do?" or a general question such as "What happened?"). In the case of specific questions, children prefer to use a null reference but use some pronouns as well (almost never using full nouns); in the case of the generic questions, children use pronouns even more often (and use nouns more as well). This finding was corroborated by some new analyses of children's use of pronouns in specific discourse situations in previously published studies. These findings suggest that children's choice of pronouns as referring expressions in early language development is influenced more by the immediately preceding discourse than other kinds of factors.

Psychometric aspects of verbal pragmatic ratings.

This study examined the psychometric aspects of a verbal pragmatic rating scale. The scale contained six pragmatic features (i.e., Conciseness, Lexical Selection, Quantity, Relevancy, Specificity, and Topic Maintenance) based on Grice's cooperative principles. Fifteen right brain-damaged (RBD), 15 left brain-damaged (LBD), and 16 healthy normal control (NC) right-handed adult participants produced narratives while recollecting emotional and nonemotional experiences. Naive raters evaluated each pragmatic feature for appropriateness on a 5-point Likert scale. When reliability was examined, the overall internal consistency of the pragmatic scale was extremely high (alpha =.96). Factor analysis was conducted to examine the theoretical relations among the six pragmatic features. Three meaningful factors involving discourse content, conceptual unity, and parsimony were identified. Findings are discussed in light of Grice's model and the construct validity of the scale.

Surface ultrastructure of pit organ, spectacle, and non pit organ epidermis of infrared imaging boid snakes: A scanning probe and scanning electron microscopy study.

Boid snakes possess unique infrared imaging pit organs. The ultrastructure of the surfaces of these organs scatter or reflect electromagnetic radiation of specific wavelengths. Pit organ epidermal surfaces of boid snakes are covered with arrays of pore-like structures called micropits. In order to determine the dimensions of this complicated surface structure, we have performed the first ultrastructural analysis on snake epidermis by high-resolution microscopy techniques. Using scanning probe microscopy and scanning electron microscopy, we found that the epidermis of pit organ, maxillary non pit organ, spectacle, and ventral scales contain arrays of micropits. These scale surfaces also contain major surface features of overlapping plate-like structures. Pit organ micropits averaged 319 nm in diameter and 46 nm in depth and were spaced an average of 808 nm from each other. These micropits were significantly deeper, of greater diameter, and spaced at greater distances apart than those of the other scales. Plate structures of the pit organs had a mean distance between plates of 3.5 microm and a mean plate step height of 151 nm. These differences serve to strengthen the argument that arrays of micropit and plate surface structures function as spectral filters or anti-reflective coatings with respect to incident electromagnetic radiation.

Similarities between the antABC-encoded anthranilate dioxygenase and the benABC-encoded benzoate dioxygenase of Acinetobacter sp. strain ADP1.

Acinetobacter sp. strain ADP1 can use benzoate or anthranilate as a sole carbon source. These structurally similar compounds are independently converted to catechol, allowing further degradation to proceed via the beta-ketoadipate pathway. In this study, the first step in anthranilate catabolism was characterized. A mutant unable to grow on anthranilate, ACN26, was selected. The sequence of a wild-type DNA fragment that restored growth revealed the antABC genes, encoding 54-, 19-, and 39-kDa proteins, respectively. The deduced AntABC sequences were homologous to those of class IB multicomponent aromatic ring-dihydroxylating enzymes, including the dioxygenase that initiates benzoate catabolism. Expression of antABC in Escherichia coli, a bacterium that normally does not degrade anthranilate, enabled the conversion of anthranilate to catechol. Unlike benzoate dioxygenase (BenABC), anthranilate dioxygenase (AntABC) catalyzed catechol formation without requiring a dehydrogenase. In Acinetobacter mutants, benC substituted for antC during growth on anthranilate, suggesting relatively broad substrate specificity of the BenC reductase, which transfers electrons from NADH to the terminal oxygenase. In contrast, the benAB genes did not substitute for antAB. An antA point mutation in ACN26 prevented anthranilate degradation, and this mutation was independent of a mucK mutation in the same strain that prevented exogenous muconate degradation. Anthranilate induced expression of antA, although no associated transcriptional regulators were identified. Disruption of three open reading frames in the immediate vicinity of antABC did not prevent the use of anthranilate as a sole carbon source. The antABC genes were mapped on the ADP1 chromosome and were not linked to the two known supraoperonic gene clusters involved in aromatic compound degradation.

Unilateral brain lesions and performance on Russell's version of the Wechsler Memory Scale in an African American population.

Studies of patients with unilateral lesions report hemisphere-specific and locus-specific impairments on Russell's (1975) Revision of the Wechsler Memory Scale (RWMS). In the current investigation "race-homogeneous" and "race-comparative" paradigms provide the context in which the generalizability of RWMS findings are examined in a population of African Americans with unilateral lesions. The performances of brain-damaged patients were impaired relative to normal controls on five of the six RWMS measures. However, patients with left and right hemisphere damage in our sample did not differ systematically on RWMS subtests. Likewise, among patients with lesions confined to one of the quadrants in the brain, there were no quadrant group differences in performance on RWMS subtests. But, right posteriors were impaired relative to controls on immediate and delayed VR subtests. The relative merits of the race-comparative and race-homogeneous paradigms are considered in the context of these findings.

What maintains the myth of the wicked stepmother?

TOPIC: A critical analysis of the myth of the wicked stepmother, its origins and social purposes, as well as factors that influence the myth and contribute to its maintenance. PURPOSE: To explore the myth of the wicked stepmother as represented in literature for professionals, parents, and children regarding the dynamics of relationships between children and stop-parents. SOURCES: Published literature and clinical observations. CONCLUSIONS: A cyclical process can be identified by reviewing the influence of myth on relationships between stepchildren and stepmothers as well as the influence of stepfamily relationships on the maintenance of myth. Solutions for stepfamily relationships require broader possibilities than the dichotomous answers provided by myth. Answers to many of the questions raised concerning the complexities of stepfamily life require an increased focus on clinical research.

Aspartate transcarbamoylase genes of Pseudomonas putida: requirement for an inactive dihydroorotase for assembly into the dodecameric holoenzyme.

The nucleotide sequences of the genes encoding the enzyme aspartate transcarbamoylase (ATCase) from Pseudomonas putida have been determined. Our results confirm that the P. putida ATCase is a dodecameric protein composed of two types of polypeptide chains translated coordinately from overlapping genes. The P. putida ATCase does not possess dissociable regulatory and catalytic functions but instead apparently contains the regulatory nucleotide binding site within a unique N-terminal extension of the pyrB-encoded subunit. The first gene, pyrB, is 1,005 bp long and encodes the 334-amino-acid, 36.4-kDa catalytic subunit of the enzyme. The second gene is 1,275 bp long and encodes a 424-residue polypeptide which bears significant homology to dihydroorotase (DHOase) from other organisms. Despite the homology of the overlapping gene to known DHOases, this 44.2-kDa polypeptide is not considered to be the functional product of the pyrC gene in P. putida, as DHOase activity is distinct from the ATCase complex. Moreover, the 44.2-kDa polypeptide lacks specific histidyl residues thought to be critical for DHOase enzymatic function. The pyrC-like gene (henceforth designated pyrC') does not complement Escherichia coli pyrC auxotrophs, while the cloned pyrB gene does complement pyrB auxotrophs. The proposed function for the vestigial DHOase is to maintain ATCase activity by conserving the dodecameric assembly of the native enzyme. This unique assembly of six active pyrB polypeptides coupled with six inactive pyrC' polypeptides has not been seen previously for ATCase but is reminiscent of the fused trifunctional CAD enzyme of eukaryotes.

Comparison of the effects of anticardiolipin antibodies from patients with the antiphospholipid syndrome and with syphilis on platelet activation and aggregation.

Anticardiolipin antibodies (aCL) are induced both in the Antiphospholipid Syndrome (APS) and syphilis, but thrombosis, thrombocytopenia, and pregnancy loss occur only in the APS. Differences in specificity and function of aCL antibodies might explain clinical differences between APS and syphilis. This study compared the effects on platelet activation and aggregation of affinity purified IgG anticardiolipin antibodies from 6 patients with the APS (IgG-APS) and 5 patients with syphilis (IgG-syph). Platelet aggregation was studied by aggregometry and platelet activation by flow cytometry. In the presence of low concentrations of thrombin, ADP, or collagen, all 6 IgG-APS samples induced platelet aggregation and activation, but none of the IgG-syph samples had this effect. In the absence of platelet agonists, only 3 of 6 IgG-APS caused platelet aggregation and none caused platelet activation; IgG-syph had no effect. The IgG-APS samples but not IgG-syph bound phosphatidylserine by ELISA. We conclude that polyclonal antibodies specific for phosphatidylserine may induce platelet activation and aggregation in the presence of low concentrations of platelet agonists.

Handedness incidence in a population of black university students.

A modified version of the Edinburgh Handedness Inventory was used to assess degrees of left-, mixed-, and right-handedness in USA and Caribbean black university students. The distributional pattern of handedness in men and women was significantly different, largely due to a higher incidence of left- and mixed-handed men. Sinistral incidence in men of this population was significantly higher than that reported in some other studies on Anglo-Saxon populations.

Effects of inferior temporal lesions on visual discrimination performance in monkeys with complete and incomplete striate cortex ablations.

In order to determine whether inferior temporal cortex participates in the relearning of visual discriminations following striatectomy, monkeys were retrained to perform two preoperatively acquired discriminations (brightness-flux and brightness-area) after receiving bilateral striate cortex lesions and then retested in the same tasks after bilateral inferior temporal surgery. After inferior temporal surgery, the monkeys with histologically verified total ablation of striate cortex showed little or no impairment in relearning the discriminations, whereas the monkeys with remnants of intact striate cortex were severely impaired. These findings suggest that inferior temporal cortex is, at most, of minor importance in relearning brightness-flux and brightness-area discriminations in the absence of striate cortex. This interpretation is consistent with the view that the contribution of inferior temporal cortex to visual discrimination performance depends on input from striate cortex.

Disorganization and reorganization of cognitive and sensorimotor functions in cerebral commissurotomy. Compensatory roles of the forebrain commissures and cerebral hemispheres in man.

Neuropsychological studies of 10 patients with complete cerebral commissurotomy and 2 with frontal commissurotomy showed differences in the nature and severity of pre-operative, initial and long-term post-operative deficits in verbal and nonverbal cognitive, memory, and sensorimotor functions. Neurosurgical findings before and after operation recorded various types of extra-callosal brain damage in all 12 patients, including 4 with gross structural lesions in the right hemisphere before surgery. Our findings revealed that differences in the nature and severity of pre-operative and post-operative deficits varied according to the nature and laterality of associated extra-callosal damage before as well as after operation. Following complete commissurotomy, all 4 patients with pre-operative structural lesions of the right hemisphere revealed a unique pattern of marked, selective impairment of nonverbal cognitive functions strikingly similar to the effects of right hemispherectomy for tumour in adults. The remaining 8 patients showed systematic patterns of greater impairment in verbal and nonverbal cognitive and contralateral sensorimotor functions, depending on the laterality of extra-callosal damage. The significantly higher pre-operative Wechsler Performance IQs of the 4 patients with structural lesions of the right hemisphere suggest that following earlier damage to the right hemisphere, the forebrain commissures contribute to a reorganization of interhemispheric relations to permit restitution of the diminished nonverbal cognitive functions resulting from damage to the right hemisphere. Thus, in addition to other possible roles in integrating the functions of the two hemispheres in the normal brain, the forebrain commissures can also serve as 'standby' or 'reserve' structures for reorganization of compensatory interhemispheric mechanisms following lateralized brain insults. Since some patients showed later postoperative improvement, the extent of ultimate competence and the 'cognitive costs' of commissurotomy can only be defined by continuing follow-up studies. Apart from their practical clinical implications, such studies may also contribute to elucidation of the principles underlying the organization, disorganization and reorganization of human brain functions.

Routine freezing of red blood cells for transfusion in Western Australia.

Experience with preservation of red cells for transfusion since 1971 has shown that refrigeration with liquid nitrogen is simple and reliable. It allows the use of a concentration of glycerol (20%) which can reasonably be removed by batch-washing if automated washing is not possible. It is possible to transport cells frozen in liquid nitrogen over long distances. This appears the method of choice for preserving rare blood, and once adopted for this purpose it is logical to use it for storage of red cells for other patients. Red cells so stored are similar in many respects to fresh cells, and more than 600 units have been transfused since 1971 without any adverse reaction.