Self-assembly of precisely defined DNA nanotube superstructures using DNA origami seeds.

We demonstrate a versatile process for assembling micron-scale filament architectures by controlling where DNA tile nanotubes nucleate on DNA origami assemblies. "Nunchucks," potential mechanical magnifiers of nanoscale dynamics consisting of two nanotubes connected by a dsDNA linker, form at yields sufficient for application and consistent with models.

Massage techniques in rehabilitation medicine.

Massage is an ancient practice that has been integrally incorporated into the management of disease and the maintenance of health across cultures and throughout time. This article discusses the history of massage and the present techniques in practice. The presumed therapeutic effects of massage and the scientific basis to support these ideas are examined. Reported contraindications and complications of massage are reviewed. Scientific research and current trends in the therapeutic use of massage are presented.

Use of corticosteroids for treating dogs with airway obstruction secondary to hilar lymphadenopathy caused by chronic histoplasmosis: 16 cases (1979-1997).

OBJECTIVE: To examine use of corticosteroids in treating dogs with airway obstruction secondary to hilar lymphadenopathy caused by chronic histoplasmosis. DESIGN: Retrospective study. ANIMALS: 16 dogs. PROCEDURE: Records for dogs with airway obstruction examined from January 1979 through December 1997 were reviewed. Dogs were included in the study if they had hilar lymphadenopathy documented radiographically and bronchoscopically, had serum antibodies against Histoplasma capsulatum, and did not have organisms in any cytologic or histologic samples. Dogs were assigned to groups on the basis of treatment given (5 dogs, corticosteroids only; 5 dogs, corticosteroids and antifungal medication; 6 dogs, antifungal medication only). RESULTS: Clinical signs resolved in < 1 week in dogs treated only with corticosteroids. In dogs treated with corticosteroids and an antifungal medication, improvement was evident in a mean of 2.6 weeks. In 5 of 6 dogs treated with only an antifungal medication, clinical signs resolved in a mean of 8.8 weeks. Dogs receiving corticosteroids did not develop active or disseminated histoplasmosis. CLINICAL IMPLICATIONS: Corticosteroids can be used successfully in the treatment of dogs with hilar lymphadenopathy secondary to histoplasmosis. Affected dogs must be carefully evaluated for active infection. Specimens obtained by means of bronchoalveolar lavage, tracheal washing, or other methods should be examined to exclude the possibility of an active infection, which could result in corticosteroid-induced dissemination of disease.

Isolation and partial characterization of a lead-accumulating Brassica juncea mutant.

A new screening method for non-destructive, high-sensitivity, high-throughput isolation of plant mutants capable of accumulating large amounts of heavy metals has been developed. This method is based on incubating seedlings in a solution containing radioisotopes of the metals of interest and visualizing the tissue accumulation of these metals with a phosphorimager. We used this technique to isolate mutants of Brassica juncea (L.) Czern with increased accumulation of Cd and Pb for use in phytoremediation, an emerging technology using plants to remediate polluted soil and water. Approximately 50,000 M2 seedlings were screened and 21 mutants were recovered that retained increased accumulation through the third generation. Mutant 7/15-1 is characterized by enhanced Pb accumulation per unit of root fresh weight, stunted root growth, and decreased root cell size. Data indicate that roots of 7/15-1 contain more cell-wall material on a fresh-weight basis than roots of the wild-type, which may at least partially explain its ability to accumulate more Pb.

A study of the workforce in emergency medicine.

STUDY OBJECTIVE: Emergency medicine has progressed significantly since its initial recognition as a medical specialty. Relatively little factual information is known, however, regarding who or how many physicians practice emergency medicine. The purpose of this study is to determine the total number of physicians practicing clinical emergency medicine during a specified period, to describe certain characteristics of those individuals, and to estimate the total number of full-time equivalents (FTEs), as well as the total number of individuals needed to staff those FTEs. METHODS: Data were gathered from a survey of a random sample of 2,062 hospitals drawn from a population of 5,220 hospitals reported by the American Hospital Association as having, or potentially having, an emergency department. The survey instrument addressed items such as descriptive data on the institution, enumeration of physicians in the ED, as well as the total number working during the period June 1, 1997, through June 14, 1997. Demographic data on the individuals were also collected. RESULTS: A total of 942 hospitals responded (a 45.7% return rate). These hospitals reported a total of 5,872 physicians were working during the specified period, or an average of 7.48 persons scheduled per institution. The physicians were scheduled for a total of 297,062 hours. The average standard for FTE was 40 clinical hours per week. This equates to 3,713 FTEs or 4.96 FTEs per institution. The ratio of persons to FTEs was 1.51:1. With regard to demographics, 83% of the physicians were men and 81% were white. Their average age was 42 years. As to professional credentials, 58% were emergency medicine-residency trained and 53% were board certified in emergency medicine; 46% were certified by the American Board of Emergency Medicine. CONCLUSION: Given that there are 4,945 hospitals with EDs and given that the data indicate there are 4.96 FTEs per ED, the total number of FTEs is projected to be 24,548 (standard error = 437). Given further that the data indicate a physician/FTE ratio of 1.51:1, we conclude that there are 36,990 persons (standard error = 683) needed to staff those FTEs. When adjusted for persons working at more than one ED, that number is reduced to 32,026.

Drug refusal behavior: the relative efficacy of skills-based and information-based treatment.

Examined the impact of two treatment strategies on children's drug refusal skills and drug-related information. Fifty-seven third graders were randomly assigned to one of three groups: rehearsal-plus, general information, and control. Children in the rehearsal-plus group were taught drug knowledge, assertiveness skills, decision-making skills, rationale and specific drug refusal skills in the context of a skills-based strategy. At a more global level, the general information group targeted all of the same components with the exception of rationale. Results indicated that children in the skills-based strategy (rehearsal-plus) showed significant improvement in behavioral skills, decision-making, and rationale, while children in the information/education-based strategy (general information) improved most on the measure of general knowledge. At follow-up, gains were generally maintained.

Octreotide-induced acute pancreatitis in a patient with acquired immunodeficiency syndrome.

Unremitting diarrhea is a common problem in patients with AIDS. We have reported the case of such a patient who was treated with the somatostatin analogue octreotide for chronic diarrhea and who had acute pancreatitis as a consequence of this therapy. We postulate that the possible mechanism for the pathogenesis of this pancreatic damage was octreotide-induced prevention of pancreatic exocrine secretion. We believe this acted as a "physiologic gallstone", inducing an attack of acute pancreatitis.

Insulin-dependent diabetes mellitus and eating disorders: a prevalence study.

There have been numerous reports in the recent literature suggesting a relationship between diabetes mellitus and the eating disorders. In the current investigation, 97 pediatric diabetes patients were administered a modified version of the Eating Habits Questionnaire, which included items specific to diabetes mellitus based on DSM-III-R criteria. None of this sample were diagnosed as anorexic and only one patient was diagnosed as currently bulimic. Possible reasons for the higher prevalence rates reported for other samples are discussed.

Cardiovascular reactivity to stress in men. Effects of masculine gender role stress appraisal and masculine performance challenge.

Previous research has shown that excessive cardiovascular reactivity may be important in the development of coronary heart disease. The present study examined the role of masculine cognitive appraisal of stress as a mediator of cardiovascular reactivity in men. The reactivity of men who differed on a measure of individual differences in men's cognitive appraisal of masculine gender role stress (MGRS) were compared on the cold-pressor test under conditions of high and low masculine performance challenge. Under conditions of minimal challenge, it was predicted that high- and low-MGRS men would not differ on reactivity. Under high challenge, high-MGRS men were expected to show greater reactivity than were low-MGRS men. Analysis of results for systolic blood pressure confirmed the major predictions. High-MGRS men showed greater systolic blood pressure reactivity than did low-MGRS men under high but not low masculine challenge. The implications of MGRS appraisal for men's health are discussed.

In defense of a modular architecture for the number-processing system: reply to Campbell and Clark.

In several recent articles we have developed a model of the cognitive number-processing and calculation systems. Campbell and Clark (1988), commenting on one of these articles (McCloskey, Sokol, & Goodman, 1986), called into question our model's assumption of a modular functional architecture and a single form of internal numerical representation. Campbell and Clark proposed as an alternative a nonmodular encoding-complex view. In this reply we discuss the results offered by Campbell and Clark as evidence against our model, arguing that several of these results are in fact consistent with the model and that the remaining results, while raising significant issues, by no means justify abandonment of the modular framework and the constraints it imposes. We also point out that whereas our model provides specific, well-motivated interpretations for a substantial body of empirical findings, the encoding-complex view is so underspecified and unconstrained as to be vacuous.

Articulatory dynamics of loud and normal speech.

A comparison was made between normal and loud productions of bilabial stops and stressed vowels. Simultaneous recordings of lip and jaw movement and the accompanying audio signal were made for four native speakers of Swedish. The stimuli consisted of 12 Swedish vowels appearing in an /i'b_b/ frame and were produced with both normal and increased vocal effort. The displacement, velocity, and relative timing associated with the individual articulators as well as their coarticulatory interactions were studied together with changes in acoustic segmental duration. It is shown that the production of loud as compared with normal speech is characterized by amplification of normal movement patterns that are predictable for the above articulatory parameters. In addition, it was observed that the acoustic durations of bilabial stops were shortened, whereas stressed vowels were lengthened during loud speech production. Two interpretations of the data are offered, viewing loud articulatory behavior as a response to production demands and perceptual constraints, respectively.

Transferring patients from residency into practice.

Recently graduated residents and their supervisors were questioned about the clinical wisdom of continuing to treat patients seen in training by transferring them to the residents' newly established private practices. Given the increasingly competitive market for psychotherapy patients, there will likely be a growing tendency for graduating residents to want to carry over patients from their training caseloads to their private practices. Questions arise concerning which patients should be offered such an option, how much to charge, whether such a practice should be encouraged, and whether transfer provides greater continuity of care. Residents were asked about their attitudes and about their clinical and supervisory experiences with such transfers. Supervisors were questioned about the indications and complexities of transfers and the specific issues that should be raised in teaching about this phenomenon. Results tended to support transferring patients from residents' training caseload to their private practices.

Orthographic ambiguity: comments on Baxter and Warrington.

In this note, I comment on a recent study by Baxter and Warrington of an acquired dysgraphic patient, KT, that appeared in Cortex, 23, 1987. The focus of my discussion centers around Baxter and Warrington's findings that: (1) KT shows a striking orthographic "regularity" effect in his spelling performance and; (2) KT's use of sound-to-spelling mapping options does not reflect the distribution of use of these options in the word corpus examined. If well-founded, the implications of these results call into question specific features of the dominant model of spelling. However, a close scrutiny of the procedures used by Baxter and Warrington in analyzing their data indicates that they collapsed across factors that have elsewhere been shown to influence spelling performance (i.e., within-syllable frequency of occurrence of phoneme-grapheme mapping options). Therefore, results obtained for patient KT cannot, in their current form, be used to speak to the specific issues of spelling that Baxter and Warrington originally set out to address.

Perceptual and cognitive abnormalities in bulimia.

The authors compared 55 bulimic subjects and 55 normal control subjects using the Beck Depression Inventory, a new scale designed to detect cognitive distortions (the Bulimia Cognitive Distortion Scale), and several perceptual and attitudinal measures of body image. There were significant differences between the bulimic and control groups on all measures except estimates of face width. These findings are discussed in terms of a multifactorial theory of the psychopathogenesis of bulimia.

Patterns of dysgraphia and the nonlexical spelling process.

This article evaluates the hypothesis that phoneme-grapheme conversion is accomplished by a passive activation device in which the selection of mapping options in the process of assembling orthography is determined by the frequency of usage of that option in the language. The spelling performance of two brain-damaged, acquired dysgraphic patients is interpreted as support for the stated hypothesis.

The development of a scale to measure cognitive distortions in bulimia.

The Bulimia Cognitive Distortions Scale (BCDS) was developed to measure irrational beliefs and cognitive distortions associated with bulimia. The final 25-item scale was found to have excellent internal consistency with high item to total correlations and a coefficient alpha of .97. Factor analysis revealed two clear factors measuring cognitive distortions related to automatic eating behaviors and to physical appearance. Data attesting to the convergent and divergent validity of the BCDS are also presented. With 110 subjects (55 bulimics, 55 controls), a discriminant analysis revealed the BCDS to be the only significant variable in predicting group membership, correctly classifying 93.6% of all subjects. The BCDS was also predictive of severity of bulimia as measured by the frequency of binge eating episodes. The potential of the BCDS as both a diagnostic and research instrument is discussed.

Comparative evaluation of the API 20S and AutoMicrobic gram-positive identification systems for non-beta-hemolytic streptococci and aerococci.

The API 20S system (Analytab Products, Plainview, N.Y.) and the AutoMicrobic Gram-Positive Identification system (GPI; Vitek Systems, Hazelwood, Mo.) were evaluated for their capacity to identify the non-beta-hemolytic streptococci and aerococci to the species level. The 20S system identified 86% (six of seven strains) of nonhemolytic group B streptococci, whereas 100% of the same group B streptococcal strains were correctly identified by the GPI system. With both systems 99% (134 of 135 strains) of four species of group D enterococcus strains and 92% (24 of 26 strains) of the Aerococcus spp. strains were identified. The 20S system identified 84% (41 of 49 strains) of three species of group D non-enterococcus strains. The GPI system identified 96% of the same group D non-enterococcus strains. The 20S system identified 84% (190 of 226 strains) of 10 species of viridans streptococci; however, supplemental conventional tests were required to identify 49% (110 of the 226 strains) of the viridans strains to the species level. The GPI system identified 79% of the same viridans streptococci without the need for supplemental tests. Both systems identified 84% (161 of 192 strains) of the seven most commonly occurring viridans Streptococcus spp. The 20S system identified 82% (75 of 92 strains) and the GPI system identified 84% (54 of 64 strains) of Streptococcus pneumoniae.

Effect of different media on determination of novobiocin resistance for differentiation of coagulase-negative staphylococci.

Species identification of coagulase-negative staphylococci often requires the determination of novobiocin susceptibility. Although previous investigators have recommended the use of P agar for this purpose, most clinical laboratories do not routinely utilize this medium. For this reason, studies were performed to compare novobiocin susceptibility results obtained with 11 different species of staphylococci (10 isolates of each species), using P agar, Trypticase soy agar with 5% sheep blood, and Mueller-Hinton agar. Tests performed on 70 susceptible isolates (minimal inhibitory concentration less than 1.6 micrograms/ml) resulted in zones of inhibition around 5-micrograms novobiocin disks ranging from 19.6 to 33.9, 16.2 to 26.6, and 21.3 to 36.4 mm on P agar, Trypticase soy agar with 5% sheep blood, and Mueller-Hinton agar, respectively. Forty resistant isolates (minimal inhibitory concentration greater than or equal to 1.6 micrograms/ml) exhibited zones of inhibition ranging from 6.0 to 11.3 mm on P agar, 6.0 to 11.6 mm on Trypticase soy agar with 5% sheep blood, and 6.0 to 13.5 mm on Mueller-Hinton agar. Using the established cut off of 16 mm to define novobiocin resistance for the identification of coagulase-negative staphylococci, we correctly identified 100% of the strains tested, regardless of the media utilized.

Employed women, dieting, and support groups.

The survey identified these employed women as being interested in dieting information (i.e., two-thirds were dieting to maintain or lose weight). The descriptions of life styles and family situations (e.g., family composition and number of hours employed) indicated a wide variation in family needs for nutrition information relating to food choices at special events and with everyday food patterns at home and eating out. These women perceived the largest number of supporting and negating dieting activities as coming from the family. Co-workers were checked about as often as the family for support activities but only about a third as often for negating activities. Associations for successful dieting imply that support occurs in both positive and negative forms. The results suggest that dieters with correct nutrition information may fail without either positive or negative support from the family and other influential groups.