Holistic Experiences and Strategies for Conducting Research With Couples.

In this article we outline methodological considerations for conducting research interviews with couples. We draw from two qualitative men’s health studies, both developed to explore social interactions between men and their partners of either sex in relation to their health practices. We utilized a combination of separate interviews and joint couple interviews. From these studies we offer insight into our experiences of using both types of interview styles, addressing four key areas which span elements across the research project journey: (a) choosing a mode of interview; (b) ethical concerns in couple research; (c) the interview as a platform for disclosure; and (d) analyzing data from couple research

The Caenorhabditis chemoreceptor gene families

Background: Chemoreceptor proteins mediate the first step in the transduction of environmental chemical stimuli, defining the breadth of detection and conferring stimulus specificity. Animal genomes contain families of genes encoding chemoreceptors that mediate taste, olfaction, and pheromone responses. The size and diversity of these families reflect the biology of chemoperception in specific species. Results: Based on manual curation and sequence comparisons among putative G-protein-coupled chemoreceptor genes in the nematode Caenorhabditis elegans, we identified approximately 1300 genes and 400 pseudogenes in the 19 largest gene families, most of which fall into larger superfamilies. In the related species C. briggsae and C. remanei, we identified most or all genes in each of the 19 families. For most families, C. elegans has the largest number of genes and C. briggsae the smallest number, suggesting changes in the importance of chemoperception among the species. Protein trees reveal family-specific and species-specific patterns of gene duplication and gene loss. The frequency of strict orthologs varies among the families, from just over 50% in two families to less than 5% in three families. Several families include large species-specific expansions, mostly in C. elegans and C. remanei. Conclusion: Chemoreceptor gene families in Caenorhabditis species are large and evolutionarily dynamic as a result of gene duplication and gene loss. These dynamics shape the chemoreceptor gene complements in Caenorhabditis species and define the receptor space available for chemosensory responses. To explain these patterns, we propose the gray pawn hypothesis: individual genes are of little significance, but the aggregate of a large number of diverse genes is required to cover a large phenotype space.JHT was supported by NIH grant RO1GM48700 and HMR by R01AI56081

Antibiotics for the primary prevention of acute rheumatic fever: a meta-analysis

BACKGROUND: Rheumatic fever continues to put a significant burden on the health of low socio-economic populations in low and middle-income countries despite the near disappearance of the disease in the developed world over the past century. Antibiotics have long been thought of as an effective method for preventing the onset of acute rheumatic fever following a Group-A streptococcal (GAS) throat infection; however, their use has not been widely adopted in developing countries for the treatment of sore throats. We have used the tools of systematic review and meta-analysis to quantify the effectiveness of antibiotic treatment for sore throat, with symptoms suggestive of group A streptococcal (GAS) infection, for the primary prevention of acute rheumatic fever. METHODS: Trials were identified through a systematic search of titles and abstracts found in the Cochrane Central Register of Controlled Trials (Cochrane Library Issue 4, 2003), MEDLINE (1966–2003), EMBASE (1966–2003), and the reference lists of identified studies. The selection criteria included randomised or quasi-randomised controlled trials comparing the effectiveness of antibiotics versus no antibiotics for the prevention of rheumatic fever in patients presenting with a sore throat, with or without confirmation of GAS infection, and no history of rheumatic fever. RESULTS: Ten trials (n = 7665) were eligible for inclusion in this review. The methodological quality of the studies, in general, was poor. All of the included trials were conducted during the period of 1950 and 1961 and in 8 of the 10 trials the study population consisted of young adult males living on United States military bases. Fixed effects, meta-analysis revealed an overall protective effect for the use of antibiotics against acute rheumatic fever of 70% (RR = 0.32; 95% CI = 0.21–0.48). The absolute risk reduction was 1.67% with an NNT of 53. When meta-analysis was restricted to include only trials evaluating penicillin, a protective effect of 80% was found (Fixed effect RR = 0.20, 95% CI = 0.11–0.36) with an NNT of 60. The marginal cost of preventing one case of rheumatic fever by a single intramuscular injection of penicillin is approximately US$46 in South Africa. CONCLUSION: Antibiotics appear to be effective in reducing the incidence of acute rheumatic fever following an episode of suspected GAS pharyngitis. This effect may be achieved at relatively low cost if a single intramuscular penicillin injection is administered

Electron ionization mass spectral fragmentation study of sulfation derivatives of polychlorinated biphenyls

<p>Abstract</p> <p>Background</p> <p>Polychlorinated biphenyls are persistent organic pollutants that can be metabolized via hydroxylated PCBs to PCB sulfate metabolites. The sensitive and selective analysis of PCB sulfate monoesters by gas chromatography-mass spectrometry (GC-MS) requires their derivatization, for example, as PCB 2,2,2-trichloroethyl (TCE) sulfate monoesters. To aid in the identification of unknown PCB sulfate metabolites isolated from biological samples, the electron impact MS fragmentation pathways of selected PCB TCE sulfate diesters were analyzed and compared to the fragmentation pathways of the corresponding methoxylated PCBs.</p> <p>Results</p> <p>The most abundant and characteristic fragment ions of PCB TCE sulfate diesters were formed by releasing CHCCl₃, SO₃, HCl₂and/or CCl₃from the TCE sulfate moiety and Cl₂, HCl, ethyne and chloroethyne from an intermediate phenylcyclopentadienyl cation. The fragmentation pattern depended on the degree of chlorination and the position of the TCE sulfate moiety (i.e., <it>ortho </it>vs. <it>meta/para </it>to the second phenyl ring), but were independent of the chlorine substitution pattern. These fragmentation pathways are similar to the fragmentation pathways of structurally related methoxylated PCBs.</p> <p>Conclusion</p> <p>Knowledge of the fragmentation patterns of PCB TCE sulfate diesters will greatly aid in determining the position of sulfate moiety (<it>ortho </it>vs. <it>meta/para</it>) of unknown PCB sulfate metabolites isolated from environmental or laboratory samples.</p

Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis

Background Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy. Methods We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance. Results We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography. Conclusion Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data

Colouration in amphibians as a reflection of nutritional status : the case of tree frogs in Costa Rica

Colouration has been considered a cue for mating success in many species; ornaments in males often are related to carotenoid mobilization towards feathers and/or skin and can signal general health and nutrition status. However, there are several factors that can also link with status, such as physiological blood parameters and body condition, but there is not substantial evidence which supports the existence of these relationships and interactions in anurans. This study evaluated how body score and blood values interact with colouration in free-range Agalychnis callidryas and Agalychnis annae males. We found significant associations between body condition and plasmatic proteins and haematocrit, as well as between body condition and colour values from the chromaticity diagram. We also demonstrated that there is a significant relation between the glucose and plasmatic protein values that were reflected in the ventral colours of the animals, and haematocrit inversely affected most of those colour values. Significant differences were found between species as well as between populations of A. callidryas, suggesting that despite colour variation, there are also biochemical differences within animals from the same species located in different regions. These data provide information on underlying factors for colouration of male tree frogs in nature, provide insights about the dynamics of several nutrients in the amphibian model and how this could affect the reproductive output of the animals

Polar Spinel-Perovskite Interfaces: an atomistic study of Fe3O4(111)/SrTiO3(111) structure and functionality

Atomic resolution scanning transmission electron microscopy and electron energy loss spectroscopy combined with ab initio electronic calculations are used to determine the structure and properties of the Fe3O4(111)/SrTiO3(111) polar interface. The interfacial structure and chemical composition are shown to be atomically sharp and of an octahedral Fe/SrO3 nature. Band alignment across the interface pins the Fermi level in the vicinity of the conduction band of SrTiO3. Density functional theory calculations demonstrate very high spin-polarization of Fe3O4 in the interface vicinity which suggests that this system may be an excellent candidate for spintronic applications

Soccer Attenuates the Asymmetry of Rectus Abdominis Muscle Observed in Non-Athletes

Purpose: To determine the volume and degree of asymmetry of the rectus abdominis muscle (RA) in professional soccer players. Methods: The volume of the RA was determined using magnetic resonance imaging (MRI) in 15 professional male soccer players and 6 non-active male control subjects. Results: Soccer players had 26% greater RA volume than controls (P<0.05), due to hypertrophy of both the dominant (28% greater volume, P<0.05) and non-dominant (25% greater volume, P<0.01) sides, after adjusting for age, length of the RA muscle and body mass index (BMI) as covariates. Total volume of the dominant side was similar to the contralateral in soccer players (P = 0.42) and in controls (P = 0.75) (Dominant/non-dominant = 0.99, in both groups). Segmental analysis showed a progressive increase in the degree of side-to-side asymmetry from the first lumbar disc to the pubic symphysis in soccer players (r = 0.80, P<0.05) and in controls (r = 0.75, P<0.05). The slope of the relationship was lower in soccer players, although this trend was not statistically significant (P = 0.14). Conclusions: Professional soccer is associated with marked hypertrophy of the rectus abdominis muscle, which achieves a volume that is 26% greater than in non-active controls. Soccer induces the hypertrophy of the non-dominant side in proximal regions and the dominant side in regions closer to pubic symphysis, which attenuates the pattern of asymmetry of rectus abdominis observed in non-active population. It remains to be determined whether the hypertrophy of rectus abdominis in soccer players modifies the risk of injury

Gene-Boosted Assembly of a Novel Bacterial Genome from Very Short Reads

Recent improvements in technology have made DNA sequencing dramatically faster and more efficient than ever before. The new technologies produce highly accurate sequences, but one drawback is that the most efficient technology produces the shortest read lengths. Short-read sequencing has been applied successfully to resequence the human genome and those of other species but not to whole-genome sequencing of novel organisms. Here we describe the sequencing and assembly of a novel clinical isolate of Pseudomonas aeruginosa, strain PAb1, using very short read technology. From 8,627,900 reads, each 33 nucleotides in length, we assembled the genome into one scaffold of 76 ordered contiguous sequences containing 6,290,005 nucleotides, including one contig spanning 512,638 nucleotides, plus an additional 436 unordered contigs containing 416,897 nucleotides. Our method includes a novel gene-boosting algorithm that uses amino acid sequences from predicted proteins to build a better assembly. This study demonstrates the feasibility of very short read sequencing for the sequencing of bacterial genomes, particularly those for which a related species has been sequenced previously, and expands the potential application of this new technology to most known prokaryotic species