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N K Smith

Publications and source records attributed to N K Smith.

At least 19 recordsLinked to original sources
PubMed2000

Development, implementation and evaluation of a new nurse-led continence service: a pilot study.

The Leicestershire Medical Research Council (MRC) Incontinence Study is a series of interrelated studies exploring the epidemiology of urinary symptoms, including incontinence, and evaluating service provision and treatment options for these symptoms. This paper describes one aspect of the Leicestershire MRC Incontinence Study, namely the development, implementation and evaluation of a new nurse-led continence service. When developing a new service it is important to determine its acceptability and suitability to the target population. The new mode of service delivery was dependent on specially trained Continence Nurse Practitioners (CNP) delivering predefined evidence-based treatment interventions. Objective and subjective outcome measures were used to evaluate the service. The service was shown to be effective in reducing urinary symptoms and led to high levels of patient satisfaction. This service is currently being evaluated in a randomized controlled trial.

Evidence-Based Medicine↗
PubMed1998

Negative information weighs more heavily on the brain: the negativity bias in evaluative categorizations.

Negative information tends to influence evaluations more strongly than comparably extreme positive information. To test whether this negativity bias operates at the evaluative categorization stage, the authors recorded event-related brain potentials (ERPs), which are more sensitive to the evaluative categorization than the response output stage, as participants viewed positive, negative, and neutral pictures. Results revealed larger amplitude late positive brain potentials during the evaluative categorization of (a) positive and negative stimuli as compared with neutral stimuli and (b) negative as compared with positive stimuli, even though both were equally probable, evaluatively extreme, and arousing. These results provide support for the hypothesis that the negativity bias in affective processing occurs as early as the initial categorization into valence classes.

Adult↗
PubMed1997

A cure for ague.

Explore the source record for details and available documents.

Cinchona↗
PubMed1997

Investigations of closure processes: what source-monitoring judgments suggest about what is "closing".

On many occasions, the perception of an object is based on incomplete information because portions of the object are occluded from view. Nevertheless, people are able to identify an occluded object, suggesting that the identification is mediated by the activation of completion processes which "fill in" the missing information. Although these completion processes are invoked as causal mechanisms for many phenomena, the processes mediating the "completion" have not been specified. The present experiments tested two potential explanations for closure processes. In each experiment, participants were presented with pictures, complete or incomplete in form, and, on a surprise source-monitoring task, they were then asked to remember whether pictures had been presented complete or incomplete in form. Whether viewing pictures of objects, faces, or camouflaged objects, participants showed a pronounced tendency to claim that incomplete pictures were actually presented complete in form. This bias was evident after the participants described functions for objects (Experiments 1, 1A, and 2), after they evaluated properties of faces (Experiment 4), and after they searched for objects hidden in a complex scene (Experiment 5). However, this bias was not evident after they simply named objects portrayed in pictures (Experiment 3). This bias is interpreted as evidence for the activation of implicit imaginal processing. The results of these experiments are informative in their contribution to our understanding of the bases of closure, an intuitively appealing notion frequently invoked to account for object identification, but, as yet, not fully understood.

Analysis of Variance↗
PubMed1996

A prospective study of urinary retention and risk of death after proximal femoral fracture.

Older age, dementia syndrome and impaired mobility are well recognized risk factors for fatality after fracture of the proximal femur. Urinary retention is recognized as a common complication of elective total hip replacement. In this investigation, we estimated the incidence of urinary retention associated with hip fracture in older women and assessed its relationship to 2-year post-operative fatality. Over a 7-month period, 309 women aged 65 and over were admitted to one trauma unit with hip fracture. Readings of post-voiding residual volume were taken on admission (pre-operative), within 24 hours of operation (post-operative) and 5-7 days post-operatively (recovery). Of the 309 patients, 244 (79%) had readings of post-voiding residual volume taken on admission; 90/244 (37%) had retention pre-operatively, 122/216 (56%) post-operatively and 40/183 (22%) in the recovery phase. One year after operation 305 patients were traced and median follow-up was 2 years. Older age, cognitive impairment, polypharmacy, impaired mobility and urinary retention on admission and during recovery were associated with a higher fatality in the first post-operative year. Pre-operative urinary retention is common among older women with proximal femoral fracture and affects over half post-operatively. Retention is one of several factors associated with higher fatality.

Aged↗
PubMed1994

Scanning the structure and antigenicity of HPV-16 E6 and E7 oncoproteins using antipeptide antibodies.

The structure and antigenicity of the HPV-16 E6 and E7 oncoproteins was studied using a set of antisera against overlapping synthetic peptides. We report that antigenic, mobile regions of the native proteins, as defined by reactivity with antipeptide antisera, occur at the N-termini of both E6 and E7 proteins, corresponding to regions of known or suspected protein-protein interactions. The putative zinc finger domains were consistently non-reactive, despite computer predictions of relatively high antigenicity, suggesting that the proposed zinc finger regions are held in stable secondary structures that the peptides were not able to mimic. In E6, the linker region between the two zinc fingers was antigenic, indicating that the two zinc finger structures might be able to articulate relative to one another by a flexible linker region. The highly antigenic N-terminal region of HPV-16 E7 was also found to be antigenic in E7 of both HPV-11 and HPV-18, indicating that the E7 proteins of different HPV types have similar antigenic structures. The identification of antigenic regions of the E6 and E7 proteins should be therefore be useful in the design of site-directed antibodies against E6 and E7 for numerous HPV types.

Amino Acid Sequence↗
PubMed1993

Serological response to HPV 16 in cervical dysplasia and neoplasia: correlation of antibodies to E6 with cervical cancer.

Sera from patients with cervical cancer, cervical intraepithelial neoplasia (CIN) and non-genital cancers, and from healthy individuals, were investigated for antibodies to human papilloma virus (HPV) early proteins E4, E6 and E7 and the major capsid protein LI by Western blot analysis of recombinant HPV proteins. There was a significantly higher prevalence of sera with antibodies to E6 in cervical cancer patients than in healthy individuals or in CIN or non-genital-cancer patients. Antibodies to E7 were detected in 25% of cervical-cancer patients, which is significantly higher than in HPV-associated cervical lesions or in control populations, but not significantly different from the incidence in patients with non-genital cancers. Antibodies to LI were found more frequently in CIN, while antibodies to E4 had a similar prevalence in cervical-cancer, cervical-dysplasia and non-genital-cancer groups, with 24% in the controls. The inability to detect antibodies to E6 and E7 in the majority of cervical-cancer patients limits the application of this methodology to the monitoring of HPV infection and the development of cervical cancer. However, the latter approach may be useful in combination with other assay systems which allow detection of different, including conformational, epitopes of HPV E6 and/or E7 recombinant proteins.

Adult↗
PubMed1993

Changes in the concentration of ions during senescence of the human erythrocyte.

Flash frozen samples of normal human blood were cryosectioned and cryodried for electron probe x-ray microanalysis of the concentration of ions and elements in individual erythrocytes (RBCs). The data (expressed in mM/kg dry weight) demonstrated a systematic pattern of variation between the concentration of ions and elements in the RBCs. Specifically as K+ and Cl- decreased in concentration, Ca2+ and sulfur increased in concentration. Phosphorous, Na+ and Mg2+ did not demonstrate a significant pattern of change. These findings are related to the dehydration and to the volume decrease that accompanies senescence of the RBC.

Calcium↗
PubMed1993

An electron microscopic comparison of bristle end-rounding of three commercial toothbrushes.

The results from three separate examinations using SEM photomicrographs and shape factor (SF) measurements show that Oral-B P-35 brushes have a highly significant difference in bristle end-rounding when compared to Colgate Precision and Crest Complete toothbrushes. The proportion of Oral-B P-35 bristles with highly rounded ends was substantially greater than that for Colgate Precision and Crest Complete toothbrushes. Oral-B also had fewer bristles in the very sharp-edged category than both Complete and Precision toothbrushes. Each toothbrush sample in these studies was purchased from geographically dispersed retail outlets throughout the United States. Scanning electron micrographs were made from a representative random sample of bristles, then digitized and evaluated using image analysis software. The comparisons were made on the basis of the number and distribution of bristles having varying degrees of roundness as determined by shape-factor analysis. Previous studies asserted that low shape-factor values indicate sharp bristle edges that are less conducive to good oral hygiene than end-rounded bristles with high SF values. In separate studies, Oral-B P-35 had a significantly higher number of highly end-rounded bristles than did either the Colgate Precision or Crest Complete toothbrushes. The averages for end-roundness fall in the order of Oral-B P-35 > Complete > Precision. Thus we conclude that the potential for harming dental tissues is less for the Oral-B P-35 toothbrush than for either the Colgate Precision or Crest Complete toothbrushes.

Analysis of Variance↗
PubMed1993

Bristle end-rounding in children's toothbrushes: a comparative study.

Animal and clinical studies have shown that sharp, unpolished toothbrush bristles can injure gingival tissues and that substantial variation exists in the degree of end-roundness of commercially available toothbrushes. In this study, eight brands of children's toothbrushes were assessed for their relative potential to cause oral tissue injury based upon the degree of end-roundness of their bristles. The brands studied were: Blend-a-dent Jr., Butler GUM Jr., Colgate Plus Jr., Johnson & Johnson Prevent Jr., Johnson & Johnson Reach Child, Lever Bros. Disney, Oral-B P20, and Sensodyne Jr. Brushes were ranked on the basis of three criteria: the percentage of bristles with sharp ends (89% roundness or less), the percentage of bristles with smooth edges (96% roundness or greater), and the average roundness of bristle ends. The Oral-B P20 brush had significantly more (p < 0.05) bristles with a roundness of 96% or greater; it also was in the group having the lowest number of bristles with sharp edges and had the highest average roundness. Based on these criteria, the Oral-B P20 showed the least potential for oral tissue damage, whereas the Johnson & Johnson Reach Child and Butler GUM Jr. showed the most potential for tissue injury. The other brands investigated were intermediate in end-rounding values and damage potential.

Child↗
PubMed1990

Post-operative urinary retention in women: management by intermittent catheterization.

We have investigated the value of intermittent catheterization in the management of post-operative urinary retention occurring in elderly women after operative fixation of lower limb fracture. Eleven patients, aged 70-86, underwent intermittent catheterization two or three times daily for between 9 and 40 days as inpatients, and one patient continued intermittent self-catheterization at home for 3 months after discharge. Ten patients became continent. One severely disabled lady required an indwelling catheter. Intermittent catheterization is safe and practical, with several advantages over indwelling catheterization in the management of post-operative urinary retention during inpatient rehabilitation.

Aged↗
PubMed1990

Evidence that a major portion of cellular potassium is "bound".

In this report we briefly review recent evidence which shows that a substantial proportion of intracellular K+ is "bound" or perturbed from the physicochemical properties expected in dilute aqueous solutions. In addition, we present evidence from electron probe x-ray microanalysis of thin cryosections of cells which indicates that the binding of K+ to anionic groups either carboxyl groups (HCO2) on proteins or to phosphate groups in creatine phosphate (CrP), in adenosine triphosphate, (ATP), in protein and in nucleic acids, are the main determinants of the maintenance of (as differentiated from the generated of) the well known intra- to extracellular K+ concentration difference. The collective evidence suggests that much of cellular K+ is reduced in its mobility and in its chemical activity due to association with negative charge groups (e.g. carboxyl and phosphates). This fact forces abandonment of the misleading assumption that the majority of intracellular K+ and other inorganic ions are as free as would be expected under ideal solution conditions. This realization should have far reaching consequences toward understanding transmembrane movement of water and solutes in cells.

Animals↗
PubMed1989

Movement of endogenous calcium in the elongating zone of graviresponding roots of Zea mays.

Endogenous calcium (Ca) accumulates along the lower side of the elongating zone of horizontally oriented roots of Zea mays cv. Yellow Dent. This accumulation of Ca correlates positively with the onset of gravicurvature, and occurs in the cytoplasm, cell walls and mucilage of epidermal cells. Corresponding changes in endogenous Ca do not occur in cortical cells of the elongating zone of intact roots. These results indicate that the calcium asymmetries associated with root gravicurvature occur in the outermost layers of the root.

Calcium↗
PubMed1989

Cellular concentration of magnesium and other ions in relation to protein synthesis, cell proliferation and cancer.

This report concerns the possible regulatory roles of intracellular Mg, Na, K, Cl, H and Ca ions in protein synthesis, mitogenesis and oncogenesis. Our main approach was to measure the intracellular concentration of various ions in different mammalian tissue cell populations for correlation with the rate of protein synthesis, the rate of cell proliferation and the tumorigenic cell state. Mg concentration alone showed a significant positive correlation to protein synthetic rate, suggesting a key role for Mg in regulation of protein synthesis. All ions measured (Mg, Na, K, Cl) showed a significant positive correlation to the rate of cell proliferation in normal populations of tissue cells. Likewise rapidly dividing tumor cells showed markedly elevated concentrations of Na and Cl but not Mg and K. The tumor cells are therefore unique in terms of their ionic composition. The injection of tumorous mice with amiloride (a drug which blocks the passive influx of Na into cells and blocks the Na-H antiport process) lowered intracellular Na concentration without significantly changing the concentration of Mg or K in the rapidly dividing tumor cells. The cell proliferation rates of both normal and of tumor cell populations were decreased by this amiloride treatment. These data strongly suggest a regulatory role for Na and H concentration on the rate of cell proliferation in both normal and tumor cells. Recent reports have shown that a brief surge in free Ca occurs after mitogenic stimulation and at several other key points in the cell cycle. These findings suggest a signaling role for free Ca in cells. A model of the temporal sequence of ionic events in the cell cycle is presented. The report ends with a brief discussion of the role of ions in tumorigenic cell transformation.

Adult↗