Improving Spanish translations of tobacco dependence measures using cognitive interviewing

BACKGROUND

Cognitive interviewing is the practice of systematically collecting feedback about survey items from members of the priority population, with the goal of identifying and rectifying problems to increase the comprehensibility of the survey. Evidence is limited on the extent to which this method of pretesting improves survey items.

OBJECTIVE

The current study examined the utility of incorporating cognitive interviewing to improve the Spanish translations of two measures of tobacco dependence.

METHODS

Items from the Spanish versions of the Wisconsin Inventory of Smoking Dependence Motives (68 items) and Nicotine Dependence Syndrome Scale (19 items) were subjected to cognitive interviews with Spanish-speaking smokers. Problematic items were revised based on participant feedback and re-assessed in a second round of interviews (N = 23, 78.3% male; 21.7% female).

RESULTS

Twenty-three of the 87 items demonstrated comprehension problems, and 67 items elicited at least one problem report. Number of problems were significantly fewer pre- vs. post-revision (t [90] = 6.55, p < .001).

CONCLUSIONS

In combination with standard translation procedures, cognitive interviewing with the priority population appears to be a useful method for ensuring comprehensible and relevant item content.

Interdisciplinary Perspectives on an Integrated Behavioral Health Model of Psychiatry in Pediatric Primary Care: A Community-Based Participatory Research Study

Integrated behavioral health services have positive outcomes for patients and providers, but little is known about providers' perspectives on implementing these services. This community-based participatory research collaboration with a Federally Qualified Health Center examined provider perspectives on implementing a collaborative psychiatry consultation program in pediatric primary care. We interviewed providers (N = 14) from psychiatry, social work, primary care, and psychology regarding their experiences implementing the program, and their recommendations for its sustainability. Providers described interdisciplinary integration arising from the program, with accompanying benefits (e.g., increased access to care for patients with complex diagnostic profiles, increased learning and role satisfaction among providers), and challenges (e.g., increased burden on primary care providers, potential patient discomfort with team-based care). Our results highlight the complexities of implementing collaborative psychiatry consultation in pediatric primary care, and suggest the importance of supporting primary care providers and patients within this context.

Poly-beta-hydroxybutyrate turnover in Azorhizobium caulinodans is required for growth and affects nifA expression

Azorhizobium caulinodans is able to fix nitrogen in the free-living state and in symbiosis with the tropical legume Sesbania rostrata. The bacteria accumulate poly-beta-hydroxybutyrate (PHB) under both conditions. The structural gene for PHB synthase, phbC, was inactivated by insertion of an interposon. The mutant strains obtained were devoid of PHB, impaired in their growth properties, totally devoid of nitrogenase activity ex planta (Nif-), and affected in nucleotide pools and induced Fix- nodules devoid of bacteria. The Nif- phenotype was the consequence of the lack of nifA transcription. Nitrogenase activity was partially restored to a phbC mutant by constitutive expression of the nifA gene. However, this constitutive nifA expression had no effect on the nucleotide content or on growth of the phbC mutant. It is suggested that PHB is required for maintaining the reducing power of the cell and therefore the bacterial growth. These observations also suggest a new control of nifA expression to adapt nitrogen fixation to the availability of carbon and reducing equivalents.

NifA-dependent expression of glutamate dehydrogenase in Rhizobium etli modifies nitrogen partitioning during symbiosis

Constitutive expression of foreign glutamate dehydrogenase in Rhizobium etli inhibits bean plant nodulation (A. Mendoza, A. Leija, E. Martínez-Romero, G. Hernández, and J. Mora. Mol. Plant-Microbe Interact. 8:584-592, 1995). Here we report that this inhibition is overcome when controlling gdhA expression by NifA, thus delaying the GDH activity onset after nodule establishment. Expression of gdhA modifies the nitrogen partitioning inside the bacteroid, where newly synthesized ammonia is preferentially incorporated into the amino acid pool instead of being exported to the infected cells. As a consequence, the fixed nitrogen transport to the leaves, measured as the ureides content in xylem sap, is significantly reduced. Nitrogenase activity, although not nifHDK expression, is significantly reduced in bacteroids expressing gdhA, probably due to the utilization of energy and reducing power for nitrogen assimilation. Here we show that ammonia assimilation inside R. etli bacteroids is active, albeit at low levels, and when enhanced is deleterious to the symbiotic performance. This leads us to believe that further reduction of the basal nitrogen metabolism in the bacteroid might stimulate the nitrogenase activity and increase the nitrogen supply to the plant.

Genetic and physiological characterization of a Rhizobium etli mutant strain unable to synthesize poly-beta-hydroxybutyrate

Rhizobium etli accumulates poly-beta-hydroxybutyrate (PHB) in symbiosis and in free life. PHB is a reserve material that serves as a carbon and/or electron sink when optimal growth conditions are not met. It has been suggested that in symbiosis PHB can prolong nitrogen fixation until the last stages of seed development, but experiments to test this proposition have not been done until now. To address these questions in a direct way, we constructed an R. etli PHB-negative mutant by the insertion of an Omega-Km interposon within the PHB synthase structural gene (phaC). The identification and sequence of the R. etli phaC gene are also reported here. Physiological studies showed that the PHB-negative mutant strain was unable to synthesize PHB and excreted more lactate, acetate, pyruvate, beta-hydroxybutyrate, fumarate, and malate than the wild-type strain. The NAD+/NADH ratio in the mutant strain was lower than that in the parent strain. The oxidative capacity of the PHB-negative mutant was reduced. Accordingly, the ability to grow in minimal medium supplemented with glucose or pyruvate was severely diminished in the mutant strain. We propose that in free life PHB synthesis sequesters reductive power, allowing the tricarboxylic acid cycle to proceed under conditions in which oxygen is a limiting factor. In symbiosis with Phaseolus vulgaris, the PHB-negative mutant induced nodules that prolonged the capacity to fix nitrogen.

The enhancement of ammonium assimilation in Rhizobium etli prevents nodulation of Phaseolus vulgaris

The modification of the ammonium assimilation pathway of Rhizobium etli (GS-GOGAT) by adding an additional ammonium assimilation enzyme, GDH, strongly affects its symbiotic interaction with beans. The plasmid pAM1a, based in the stable vector pTR101 (M. Weinstein, R. C. Roberts, and D. R. Helsinki, J. Bacteriol. 174,7486-7489, 1992), containing the Escherichia coli gdhA gene flanked by two transcription-translation terminators was constructed. The expression of GDH in both, the wild type (CFN42/pAM1a) and a ntrC- mutant (CFN2012/pAM1a) R. etli strains, gave a similar metabolic effect, i.e., high GDH and reduced GOGAT activities, and an increased synthesis and excretion of several amino acids. The total inhibition of bean nodulation was observed when the minimum optimal inoculum of R. etli CFN42/pAM1a was used; however, an effective symbiosis occurred with the CFN2012/pAM1a mutant strain. While a total inhibition of the induction of the nodA gene by bean root exudate or by naringenin was observed in the CFN42/pAM1a strain, at 10 mM ammonium, the CFN2012/pAM1a showed an optimal nodA gene induction. A correlation between nodA gene induction, Nod factor production, and nodulation was observed. We conclude that in R. etli, there is a down-regulation of nod gene expression and nodulation when a high internal nitrogen content is built up by the presence of a functional GDH and that NtrC is involved in such regulation. An instability of the plasmid harboring the gdhA gene was observed during symbiosis, indicating a strong selection against cells containing this plasmid.

Genomic instability in Rhizobium phaseoli

Experience from different laboratories indicates that Rhizobium strains can generate variability in regard to some phenotypic characteristics such as colony morphology or symbiotic properties. On the other hand, several reports suggest that under certain stress conditions or genetic manipulations Rhizobium cells can present genomic rearrangements. In search of frequent genomic rearrangements, we analyzed three Rhizobium strains under laboratory conditions that are not considered to cause stress in bacterial populations. DNAs from direct descendants of a single cell were analyzed in regard to the hybridization patterns obtained, using as probes different recombinant plasmids or cosmids; while most of the probes utilized did not show differences in the hybridization patterns, some of them revealed the occurrence of frequent genomic rearrangements. The implications and possible biological significance of these observations are discussed.

Effect of L-amino acids on Mucor rouxii dimorphism

Mucor rouxii organisms growing aerobically and exponentially on a well-defined minimal medium are able to differentiate as yeasts or as mycelia, depending on the amino acid as the nitrogen source. When certain amino acids were used as the nitrogen source, spores differentiated only as hyphae, whereas other amino acids gave rise to other morphological forms having different ratios of yeasts to hyphae. In both hyphal and yeast cultures, an aerobic metabolism was predominant, as shown by determining several metabolic parameters such as oxygen tension, glucose consumption, ethanol production, and CO2 release. A complete conversion of yeasts to hyphae was obtained by the appropriate change in the amino acid used as nitrogen source. By preparing spheroplasts from mycelial cultures and transferring them to media with amino acids that induce yeast formation, a 50% yield in the reverse transformation was achieved. A correlation between the change in pH of the medium and cell morphology was observed in different growth conditions. Decrease in the pH of the medium preceded the appearance of hyphae. Also, when the initial pH of the medium was increased, aspartate-containing cultures developed mainly as mycelia, instead of yeasts, with a corresponding decrease in the final pH.