Effectiveness of behavioural interventions to reduce urinary tract infections and Escherichia coli bacteraemia for older adults across all care settings: a systematic review.

BACKGROUND: Escherichia coli bacteraemia rates in the UK have risen; rates are highest among older adults. Previous urinary tract infections (UTIs) and catheterization are risk factors. AIM: To examine effectiveness of behavioural interventions to reduce E. coli bacteraemia and/or symptomatic UTIs for older adults. METHODS: Sixteen databases, grey literature, and reference lists were searched. Titles and/or abstracts were scanned and selected papers were read fully to confirm suitability. Quality was assessed using Critical Appraisal Skills Programme guidelines and Scottish Intercollegiate Guidelines Network grading. FINDINGS: Twenty-one studies were reviewed, and all lacked methodological quality. Six multi-faceted hospital interventions including education, with audit and feedback or reminders reduced UTIs but only three supplied statements of significance. One study reported decreasing catheter-associated UTI (CAUTI) by 88% (F (1,20) = 7.25). Another study reported reductions in CAUTI from 11.17 to 10.53 during Phase I and by 0.39 during Phase II (χ2 = 254). A third study reported fewer UTIs per patient week (risk ratio = 0.39). Two hospital studies of online training and catheter insertion and care simulations decreased CAUTIs from 33 to 14 and from 10.40 to 0. Increasing nursing staff, community continence nurses, and catheter removal reminder stickers reduced infection. There were no studies examining prevention of E. coli bacteraemias. CONCLUSION: The heterogeneity of studies means that one effective intervention cannot be recommended. We suggest that feedback should be considered because it facilitated reductions in UTI when used alone or in multi-faceted interventions including education, audit or catheter removal protocols. Multi-faceted education is likely to be effective. Catheter removal protocols, increased staffing, and patient education require further evaluation.

Technical and patient-related characteristics associated with challenging retrieval of inferior vena cava filters.

OBJECTIVE: To identify patient-related and device-specific predictors of challenging and failed inferior vena cava (IVC) filter retrievals. METHODS: Retrospective single center review of consecutive retrievable IVC filters placed between 2004 and 2009. Retrieval was defined as challenging when it was unsuccessful owing to reported technical failure or when adjunctive endovascular maneuvers or access sites were recruited. Data regarding patient- and filter-specific information were collected. Logistic regression models were used to identify predictors of the reported outcomes. Statistical significance was set at p < .05. RESULTS: Four hundred and one patients underwent retrievable IVC filter placement-the majority indicated for prophylaxis (67%). Two hundred and fifty-nine retrievals were attempted and 237 filters were successfully retrieved (overall retrieval rate: 59.1%). Eleven out of 259 (4.2%) attempts were aborted owing to significant thrombus within the filter and 11 (4.2%) were technically unsuccessful. In 142 patients no attempt for filter retrieval was made-the major reason being physician oversight (44.3%). Thirty-eight out of 248 (15.3%) non-aborted filter retrievals were recorded as challenging. Failed retrievals were predicted by prolonged dwell time (96.9 ± 111.9 vs. 29.5 ± 25.1 days, odds ratio [OR] 1.034, 95% confidence interval [CI] 1.016-1.053, p < .001), therapeutic indication (OR 5.197, 95% CI 1.200-22.511, p = .028), and filter wall apposition (OR 11.857, 95% CI 2.069-67.968, p = .006). Challenging retrievals were predicted by dwell time (51.1 ± 69.8 vs. 29.1 ± 24.5 days, OR 1.017, 95% CI 1.005-1.029, p = .007), filter tilt (OR 2.607, 95% CI 1.045-6.508, p = .040) and filter wall apposition (OR 6.149, 95% CI 2.398-15.763, p = <.001). CONCLUSIONS: Physician oversight leads to poor IVC filter retrieval rates. Retrievals can be challenging or fail when the dwell time is >50 days and >90 days, respectively, and when the filter hook apposes the caval wall. Filter tilt increases retrieval difficulty but not failure rates.

Coordinated chemomechanical cycles: a mechanism for autonomous molecular motion.

The second law of thermodynamics requires that directed motion be accompanied by dissipation of energy. Here we demonstrate the working principles of a bipedal molecular motor. The motor is constructed from DNA and is driven by the hybridization of a DNA fuel. We show how the catalytic activities of the feet can be coordinated to create a Brownian ratchet that is in principle capable of directional and processive movement along a track. This system can be driven away from equilibrium, demonstrating the potential of the motor to do work.

Psychological care of the haemodialysis patient.

The psychological care of patients at the haemodialysis unit is becoming an increasingly important aspect of the overall treatment of patients with end-stage renal failure. As more is understood and reported regarding the impact of psychological factors on physical processes it becomes crucial that good quality psychological care is delivered to patients by nurses working at the haemodialysis unit. This study aimed to look at haemodialysis patients' perceptions of their treatment to discover if a dialysis centre in Southern England might benefit from a more formal system of psychological care. The data revealed four main themes that were of particular importance to the participants of this study: The New Self, Coping, Medical Concerns and Psychological Care. Within these areas of importance, the need for good quality information, the need for a suitable dialysis environment and the importance of social and family support were evident. Although the psychological care system that was in place at the unit appeared to be working well a more formal system of care might improve the patient experience.

DNA transport in bacteria.

DNA transport is important in various biological contexts--particularly chromosome segregation and intercellular gene transfer. Recently, progress has been made in understanding the function of a family of bacterial proteins involved in DNA transfer, and we focus here on one of the best-understood members, SpoIIIE. Studies of SpoIIIE-like proteins show that they might couple DNA transport to processes such as cell division, conjugation (mating) and the resolution of chromosome dimers.

Role of Bacillus subtilis SpoIIIE in DNA transport across the mother cell-prespore division septum.

The SpoIIIE protein of Bacillus subtilis is required for chromosome segregation during spore formation. The COOH-terminal cytoplasmic part of SpoIIIE was shown to be a DNA-dependent adenosine triphosphatase (ATPase) capable of tracking along DNA in the presence of ATP, and the NH(2)-terminal part of the protein was found to mediate its localization to the division septum. Thus, during sporulation, SpoIIIE appears to act as a DNA pump that actively moves one of the replicated pair of chromosomes into the prespore. The presence of SpoIIIE homologs in a broad range of bacteria suggests that this mechanism for active transport of DNA may be widespread.

Cytochrome P450 CYP2D6 genotypes: association with hair colour, Breslow thickness and melanocyte stimulating hormone receptor alleles in patients with malignant melanoma.

We previously identified associations between polymorphism in the cytochrome P450 CYP2D6 gene and outcome in several cancers. We have now examined the hypothesis that homozygosity for the mutant alleles, CYP2D6*4 and CYP2D6*3, is associated with susceptibility and outcome in malignant melanoma. Outcome was assessed by Breslow thickness. We first confirmed previous reports that these mutant alleles are associated with increased susceptibility to malignant melanoma. For example, the frequency of homozygosity for CYP2D6*4 was significantly greater (P = 0.006, chi-squared 1 d.f. = 7.4, odds ratio 2.2, 95% confidence interval 1.2, 3.9) in cases (9.1%) than in control individuals (4.3%). The frequency of homozygosity for the mutant alleles was next examined in the malignant melanoma cases grouped on the basis of characteristics associated with malignant melanoma risk. Homozygosity was significantly more common (P = 0.038) in cases with red/blonde hair than in those with brown/black hair. We found no associations between the CYP2D6 genotype and sex, skin type or eye colour. The possible association of CYP2D6 with outcome was assessed by comparing genotype frequencies in patients with tumours of Breslow thickness < 1.5 mm with those whose tumours were > or = 1.5 mm. In patients with red/blonde, but not brown or black hair, homozygosity for CYP2D6*4 was significantly associated with thicker lesions in a multivariate model (P = 0.036). We further examined the association of CYP2D6*4 homozygosity with red/blonde hair by classifying patients on the basis of homo- or heterozygosity for wild-type or val92met, asp294his or asp84glu melanocyte stimulating hormone receptor (MC1R) alleles. None of the nine patients with brown/black hair with the asp294his allele were homozygotes for CYP2D6*4. By contrast, in the patients with red/blonde hair, three of five cases with asp294his were homozygotes for the mutant CYP2D6 allele. The difference in the frequency of CYP2D6*4 homozygotes in the red/blonde cases with wild-type MC1R alleles compared with those with asp294his was significant (exact P = 0.029). No associations between val92his or asp84glu and CYP2D6 alleles were identified.

Topology of Xer recombination on catenanes produced by lambda integrase.

Xer site-specific recombination at the psi site from plasmid pSC101 displays topological selectivity, such that recombination normally occurs only between directly repeated sites on the same circular DNA molecule. This intramolecular selectivity is important for the biological role of psi, and is imposed by accessory proteins PepA and ArcA acting at accessory DNA sequences adjacent to the core recombination site. Here we show that the selectivity for intramolecular recombination at psi can be bypassed in multiply interlinked catenanes. Xer site-specific recombination occurred relatively efficiently between antiparallel psi sites located on separate rings of right-handed torus catenanes containing six or more nodes. This recombination introduced one additional node into the catenanes. Antiparallel sites on four-noded right-handed catenanes, the normal product of Xer recombination at psi, were not recombined efficiently. Furthermore, parallel psi sites on right-handed torus catenanes were not substrates for Xer recombination. These findings support a model in which psi sites are plectonemically interwrapped, trapping a precise number of supercoils that are converted to four catenation nodes by Xer strand exchange.

Patient perceptions of rheumatoid arthritis.

Rheumatoid arthritis is rarely seen as a serious public health issue, yet it is the single largest cause of disability in the UK (Badley and Tennant 1993). In this qualitative study patients were interviewed about the physical and social effects of the disease.

Susceptibility to melanoma: influence of skin type and polymorphism in the melanocyte stimulating hormone receptor gene.

Allelic variation at the melanocyte stimulating hormone receptor (MC1R) gene has been linked with sun-sensitive skin types, suggesting it is a susceptibility candidate for melanoma. We determined the frequency of the val92met, asp294his, and asp84glu MC1R alleles in 190 Caucasian controls and 306 melanoma cases and studied their association with skin type and hair color. The percentage of controls with at least one val92met, asp294his, or asp84glu allele was 17.3%, 6.8%, and 3.5%, respectively. Individually, frequencies of the val92met, asp294his, or asp84glu alleles in the controls with skin types 3 and 4 were similar to those with skin types 1 and 2. Trend analysis, however, did identify an association (exact p = 0.048, two-sided test) between skin type and MC1R variants in the group comprising all controls with any one or more of these alleles. There was no association between MC1R alleles and hair color. Allele frequencies were not different in melanoma cases and controls. There were no associations between skin types and the proportion of cases with the asp294his or asp84glu alleles, though the association between skin type and the val92met allele approached significance (exact p = 0.09, two-sided test). Unexpectedly, in the group comprising all cases with one or more variant alleles, the proportion of subjects with variant alleles increased with skin types associated with tanning rather than burning, although trend analysis showed that this association did not quite reach statistical significance (exact p = 0.08, two-sided test). Asp84glu (but not val92met or asp294his) variant alleles were more common in subjects with blonde hair, although the relationship between the asp84glu allele and hair color did not achieve statistical significance (chi(2)3 = 6.16, exact p = 0.10). We interpret the data presented as indicating that polymorphism at MC1R does not appear a major determinant of skin type, at least in terms of these allelic variants. Furthermore, considered alone, these alleles are not susceptibility candidates for malignant melanoma.

Polymorphism in cytochrome P450 CYP2D6, CYP1A1, CYP2E1 and glutathione S-transferase, GSTM1, GSTM3, GSTT1 and susceptibility to tobacco-related cancers: studies in upper aerodigestive tract cancers.

Glutathione S-transferase GSTM1, GSTM3 and GSTT1 and cytochrome P450 CYP2D6, CYP1A1 and CYP2E1 loci are susceptibility candidates for cancers of the upper aerodigestive tract because putatively protective and risk genotypes have been identified from studies in other diseases associated with alcohol and tobacco consumption. We describe genotype frequencies in 398 oral, pharyngeal and laryngeal squamous cell carcinoma patients and 219 control individuals. Of the genotypes presumed to be protective, only GSTM1 A/B influenced susceptibility; the GSTM1 A/B frequency was lower in the patients than the control individuals both before [odds ratio = 0.3, 95% confidence interval (CI) 0.1-0.7] and after correction for imbalances in age, sex, smoking and alcohol consumption (odds ratio = 0.2, 95% CI 0.1-0.5). Of the putatively risk genotypes, GSTM3 AA, previously associated with susceptibility to skin cancer, was higher in the cases (odds ratio = 1.6, 95% CI 1.1-2.4). Dividing cases into oral/pharyngeal and laryngeal squamous cell carcinoma showed the GSTM3 AA frequency was higher in laryngeal squamous cell carcinoma than control individuals (odds ratio = 1.6, 95% CI 1.1-2.5) and the difference between control individuals and oral/pharyngeal squamous cell carcinoma approached significance (odds ratio = 1.7, 95% CI 1.0-2.8). The putatively protective GSTM3 BB genotype was lower in patients with glottic (1.0%) than supraglottic (3.0%) squamous cell carcinoma. We identified no differences between patients and control individuals in the frequencies of presumed risk genotypes (e.g. CYP2D6 EM, CYP1A1 m1/m1, CYP1A1 Ile/Ile, CYP2E1 DD, CYP2E1 c1c1, GSTT1 null) or, interactions between genotypes and smoking or alcohol consumption. We conclude, first, that mu class glutathione S-transferase influence risk of upper aerodigestive tract cancers thereby complementing studies in skin cancer patients showing GSTM1 A/B is protective, while GSTM3 AA moderately increases risk. The influence of GSTM1 A/B, but not GSTM1 A or GSTM1 B (mostly heterozygotes with GSTM1*0) suggests that two expressed alleles may attenuate risk. While we found immunohistochemical evidence of GSTM3 expression in the cilia lining the larynx, the biochemical consequences of the polymorphism are unclear. Indeed, the influence of the gene may reflect linkage disequilibrium with another gene. However, we did not find an association with GSTM1 genotypes. Second, we conclude that the CYP2D6, CYP2E1, CYP1A1 and GSTT1 alleles studied, although putatively good candidates, either do not determine the effectiveness of detoxification of tobacco-derived carcinogens in the upper aerodigestive tract or, that chronic consumption of tobacco and alcohol overwhelms enzyme defences, irrespective of genotype.

Topological selectivity in Xer site-specific recombination.

The product topology of Xer-mediated site-specific recombination at plasmid sites has been determined. The product of deletion at pSC101 psi is a right-handed antiparallel 4-noded catenane. The ColE1 cer deletion product has an identical topology, except that only one pair of strands is exchanged. These specific product topologies imply that the productive synaptic complex and the strand exchange mechanism have fixed topologies. Further analysis suggests that synapsis traps exactly three negative supercoils between recombining sites, and that strand exchange introduces a further negative topological node in the deletion reaction. We present a model in which the requirement for a specific synaptic stucture, with two recombination sites interwrapped around the accessory proteins ArgR and PepA, ensures that recombination only occurs efficiently between directly repeated sites on the same DNA molecule.

Learning style as a predictor of drug dosage calculation ability.

This study measured the learning style in mathematics of nursing students to determine if there was a correlation with their ability to calculate drug dosages. The results seem to indicate that instructors can improve the ability of their students to calculate drug dosages by integrating instructional methods that 1) reinforce the student's preferred learning style; and 2) require the student to use both sequential, step-by-step, paper and pencil processing and global, all-at-once mental processing.

Drug calculation errors of baccalaureate nursing students.

Most researchers who study the dosage calculation skills of nursing students have looked at the mathematical or computational ability of the students. The authors report findings from a study that analyzed the dosage calculation errors of nursing students from conceptual, mathematical, and measurement perspectives.

Post-traumatic hypothalamic-pituitary dysfunction presenting with biochemical features of primary hypothyroidism.

Two cases of post-traumatic hypothalamic-pituitary dysfunction are described where the primary pathology was shown to be understimulation of the pituitary by hypothalamic hormones. In each case, the biochemical presentation was a low serum thyroxine and elevated TSH concentration mimicking primary hypothyroidism. Treatment with thyroxine before cortisol replacement was not beneficial. In both cases, hydrocortisone therapy alone resulted in a rise in serum thyroxine and fall in serum TSH. Chronic cortisol deficiency may directly impair the thyroid response to TSH, whilst thyroxine appears to exert its feedback primarily at pituitary rather than hypothalamic level.

Sarcoidosis and primary hypogammaglobulinaemia: a report of two cases and a review of the literature.

We are aware of only four previous cases of Kveim positive sarcoidosis reported in hypogammaglobulinaemic patients and we describe two further patients. Patients with hypogammaglobulinaemia and a sarcoid-like syndrome or sarcoidosis have been reviewed. Similarities between sarcoidosis and a subgroup of late onset primary hypogammaglobulinaemia have been highlighted. It is suggested that sarcoidosis in this patient population is probably commoner than was previously thought, but the association between the two conditions remains unclear.