Plasmonic nanocone arrays for rapid and detailed cell lysate surface enhanced Raman spectroscopy analysis.

In this work, we develop, fabricate, and characterize a plasmonic nanocone array surface enhanced Raman spectroscopy (SERS) substrate with a uniform enhancement factor on the micron scale for qualitative and quantiative cell and cell lysate analysis. This work demonstrates how SERS substrates can be used as cell-based biosensors given that the enhancement factor of the substrate is sufficient for Raman detection and that the uniformity is high over the applicable surface area. These requirements allow accurate and quantitative comparisons between nonuniform samples under varying biochemical conditions. We apply the developed SERS substrate for Raman measurements and mapping of HeLa cells and cell lysate. This method is used for identification of UV-induced damage and detection of nanomolar concentrations of methylated guanine spiked in cell lysate samples.

Label-free cell-substrate adhesion imaging on plasmonic nanocup arrays.

Cell adhesion is a crucial biological and biomedical parameter defining cell differentiation, cell migration, cell survival, and state of disease. Because of its importance in cellular function, several tools have been developed in order to monitor cell adhesion in response to various biochemical and mechanical cues. However, there remains a need to monitor cell adhesion and cell-substrate separation with a method that allows real-time measurements on accessible equipment. In this article, we present a method to monitor cell-substrate separation at the single cell level using a plasmonic extraordinary optical transmission substrate, which has a high sensitivity to refractive index changes at the metal-dielectric interface. We show how refractive index changes can be detected using intensity peaks in color channel histograms from RGB images taken of the device surface with a brightfield microscope. This allows mapping of the nonuniform refractive index pattern of a single cell cultured on the plasmonic substrate and therefore high-throughput detection of cell-substrate adhesion with observations in real time.

Quantitative phase imaging with partially coherent illumination.

In this Letter, we formulate a mathematical model for predicting experimental outcomes in quantitative phase imaging (QPI) when the illumination field is partially spatially coherent. We derive formulae that apply to QPI and discuss expected results for two classes of QPI experiments: common path and traditional interferometry, under varying degrees of spatial coherence. In particular, our results describe the physical relationship between the spatial coherence of the illuminating field and the halo effect, which is well known in phase-contrast microscopy. We performed experiments relevant to this common situation and found that our theory is in excellent agreement with the data. With this new understanding of the effects of spatial coherence, our formulae offer an avenue for removing halo artifacts from phase images.

Epi-illumination diffraction phase microscopy with white light.

We demonstrate the first reflection-based epi-illumination diffraction phase microscope with white light (epi-wDPM). The epi-wDPM system combines the off-axis, common-path, and white light approaches, in a reflection geometry enabling sub-nanometer spatial and temporal noise levels, while providing single-shot acquisition for opaque samples. We verified the epi-wDPM results by measuring control samples with known dimensions and comparing them to measurements from other well-established techniques. We imaged gold-coated HeLa cells to illustrate the tradeoffs between epi-wDPM with low and high spatial coherence.

Effects of linseeds on the symptoms of irritable bowel syndrome: a pilot randomised controlled trial.

BACKGROUND: Manipulation of dietary fibre intake represents a longstanding treatment for patients with irritable bowel syndrome (IBS), particularly for those with constipation. Linseeds are often recommended by both clinicians and dietitians as a source of dietary fibre to alleviate symptoms. Recent guidance on the management of irritable bowel syndrome (IBS) advises that linseeds may reduce wind and bloating, although there is limited clinical evidence to support this recommendation. The present pilot study aimed to compare the clinical effectiveness of: (i) whole linseeds versus ground linseeds; (ii) whole linseeds versus no linseeds; and (iii) ground linseeds versus no linseeds in the management of IBS symptoms. METHODS: In an open randomised controlled trial, subjects with IBS (n = 40) were allocated to one of three intervention groups: two tablespoons of whole linseeds per day (n = 14), two tablespoons of ground linseeds per day (n = 13) and no linseeds as controls (n = 13). Symptom severity (primary outcome) and bowel habit were assessed before and after a 4-week intervention and statistical differences between the groups were compared. RESULTS: Thirty-one subjects completed the present study. Between-group analysis comparing the improvement in symptom severity did not reach statistical significance for whole linseeds (n = 11) versus ground linseeds (n = 11; P = 0.62), whole linseeds versus controls (n = 9; P = 0.12) and ground linseeds versus controls (P = 0.10). There were no significant changes in stool frequency or stool consistency for any of the groups. CONCLUSIONS: Linseeds may be useful in relief of IBS symptoms. Further research is needed to detect clear differences between the effects of whole and ground linseeds.

British Dietetic Association evidence-based guidelines for the dietary management of irritable bowel syndrome in adults.

BACKGROUND: Irritable bowel syndrome (IBS) is a chronic debilitating functional gastrointestinal disorder. Diet and lifestyle changes are important management strategies. The aim of these guidelines is to systematically review key aspects of the dietary management of IBS, with the aim of providing evidence-based guidelines for use by registered dietitians. METHODS: Questions relating to diet and IBS symptom management were developed by a guideline development group. These included the role of milk and lactose, nonstarch polysaccharides (NSP), fermentable carbohydrates in abdominal bloating, probiotics and empirical or elimination diets. A comprehensive literature search was conducted and relevant studies from January 1985 to November 2009 were identified using the electronic database search engines: Cinahl, Cochrane Library, Embase, Medline, Scopus and Web of Science. Evidence statements, recommendations, good practice points and research recommendations were developed. RESULTS: Thirty studies were critically appraised. A dietetic care pathway was produced following a logical sequence of treatment and formed the basis of these guidelines. Three lines of dietary management were identified. first line: Clinical and dietary assessment, healthy eating and lifestyle management with some general advice on lactose and NSP. Second line: Advanced dietary interventions to improve symptoms based on NSP, fermentable carbohydrates and probiotics. Third line: Elimination and empirical diets. Research recommendations were also identified relating to the need for adequately powered and well designed randomised controlled trials. CONCLUSIONS: These guidelines provide evidence-based details of how to achieve the successful dietary management of IBS.

Functional clinical placements: a driver for change.

The aim of the project was to create a supervised professional experience placement model involving undergraduate nursing students, families of children with intellectual disabilities and nursing lecturers. Action research provided the methodological framework for developing a new placement model. Five families with children with disabilities, nine nursing students and two nurse academics worked together through the cycles of the action research process to develop a family health promotion intervention to improve the health and wellness of the family members and reduce risk for illness. Awareness, valuing and understanding were key themes derived from the qualitative data. Findings of this project indicate that this model of university-initiated, community-focused professional experience placement is effective in achieving the competency-based learning outcomes required of undergraduate nursing students and is worthy of ongoing exploration.

Safety and cost savings of an improved three-day rule for stool culture in hospitalised children and adults.

Stools sent for culture from patients after three days of hospitalisation have a low yield (<1%) for bacterial enteric pathogens (BEP), excluding Clostridium difficile, and are expensive to process. A 'three-day rule' for rejection of specimens has previously been validated in adults. We evaluated a three-day rule for paediatric stool samples by retrospective review of all stool culture results from 1995 to 2002. Excluding C. difficile, yield for BEP in samples sent within three days following admission was 97/3751 (2.59%) compared with 3/1511 (0.2%) in samples sent more than three days after admission. The criteria for culture would have been met if the rule had been applied for these three samples. We prospectively evaluated potential savings if the rule were applied for both children and adults over a two-month period in 2000. Savings were greater for adults than for children. Of 490 stools from children, 38 (7.8%) samples did not meet the criteria for culture and of 206 stools from adult patients, 64 (31%) did not meet the criteria for culture. We implemented the rule between 1 March 2003 and 31 March 2006. A total of 14 439 stool samples were received from inpatients requesting culture for BEP, excluding C. difficile. Of these, 5744 (39.8%) were rejected because the criteria for culture were not met. This was estimated as an annual saving of 11,848 pounds to the Trust laboratory. If extrapolated to all NHS Trusts, the potential savings could be in the order of 1.18 million pounds annually.

Insulin-like growth factor-I receptor signalling and acquired resistance to gefitinib (ZD1839; Iressa) in human breast and prostate cancer cells.

De novo and acquired resistance to the anti-tumour drug gefitinib (ZD1839; Iressa), a specific epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) has been reported. We have determined whether signalling through the IGF-I receptor (IGF-1R) pathway plays a role in the gefitinib-acquired resistance phenotype. Continuous exposure of EGFR-positive MCF-7-derived tamoxifen resistant breast cancer cells (TAM-R) to 1 microM gefitinib resulted in a sustained growth inhibition (90%) for 4 months before the surviving cells resumed proliferation. A stable gefitinib-resistant subline (TAM/TKI-R) was established after a further 2 months and this showed no detectable basal phosphorylated EGFR activity. Compared with the parental TAM-R cells, the TAM/ TKI-R cells demonstrated (a) elevated levels of activated IGF-1R, AKT and protein kinase C (PKC)delta, (b) an increased sensitivity to growth inhibition by the IGF-1R TKI AG1024 and (c) an increased migratory capacity that was reduced by AG1024 treatment. Similarly, the EGFR-positive androgen-independent human prostate cancer cell line DU145 was also continuously challenged with 1 microM gefitinib and, although substantial growth inhibition (60%) was seen initially, a gefitinib-resistant variant (DU145/TKI-R) developed after 3 months. Like their breast cancer counterparts, the DU145/TKI-R cells showed increases in the levels of components of the IGF-1R signalling pathway and an elevated sensitivity to growth inhibition by AG1024 compared with the parent DU145 cell line. Additionally, DU145/TKI-R cell migration was also decreased by this inhibitor. We have therefore concluded that in breast and prostate cancer cells acquired resistance to gefitinib is associated with increased signalling via the IGF-1R pathway, which also plays a role in the invasive capacity of the gefitinib-resistant phenotype.

The effects of specific retrieval instruction on social problem-solving in depression.

OBJECTIVES: We examine the proposal that social problem-solving in depression may be improved with the retrieval of specific autobiographical memories. DESIGN AND METHODS: Social problem-solving was assessed with the Means-End Problem-Solving task (MEPS; Platt & Spivack, 1975a). Depressed and non-depressed participants were required either to retrieve a specific memory prior to generating a MEPS solution (primed condition) or to report on the memories retrieved during MEPS performance after giving their MEPS solution (non-primed condition). Participants also judged whether the memories retrieved had been helpful or unhelpful for the process of solution generation. RESULTS: In both depressed and non-depressed individuals, priming increased specific memory retrieval but did not improve MEPS performance. An interaction between depression and priming revealed that priming increased the retrieval of helpful memories in the depressed sample. CONCLUSIONS: Specificity is not, in itself, a sufficient retrieval aim for successful social problem-solving. However specific memory priming may be beneficial in depression because it facilitates the recognition of memories which are helpful for problem-solving.

Effect of an EGF-R selective tyrosine kinase inhibitor and an anti-androgen on LNCaP cells: identification of divergent growth regulatory pathways.

BACKGROUND: The effect of an EGF-R selective tyrosine kinase (EGF-RTK) quinazoline inhibitor ZM252868 was determined on the androgen-sensitive human prostatic tumour cell line LNCaP, which can also respond via the EGF-R-regulated growth pathway for cell proliferation. Potential interaction or 'cross-talk' between steroid and the growth factor mitogen-activated protein kinase (MAPK) signalling pathway was also investigated. METHODS: The responses of LNCaP cells to various growth factors in the absence and presence of the EGF-RTK inhibitor and/or steroid and anti-androgen Casodex, was determined using cell population analysis. The effect of the inhibitor on the expression of androgen receptor, EGF-R and activated MAPK was assessed immunocytochemically and changes in the MAPK signalling cascade were also determined using Western blotting techniques. RESULTS: The ZM252868 inhibitor had no effect on LNCaP basal growth. At 100 nM and 1 microM concentrations, the inhibitor reduced the marked EGF- and TGF-alpha-stimulated LNCaP cell growth by 60% and to basal levels, respectively. Both bFGF- and 5alpha-DHT-stimulated growth were unaffected in this concentration range. The inhibitor (1 microM) decreased the expression of immunoreactive EGF-R but had no effect on androgen receptor levels. Activation of MAPK by EGF was noted, being down-regulated by the inhibitor at a concentration of 1 microM. MAPK was not activated by 5alpha-DHT. The anti-androgen Casodex reduced 5alpha-DHT-stimulated cell growth but had no effect on EGF-R mediated LNCaP growth or EGF-stimulated activated MAPK activity. Treatment with EGF and 5alpha-DHT in combination produced an additive effect on cell proliferation, with the anti-androgen and the EGF-RTK inhibitor only reducing the 5alpha-DHT- or EGF-stimulated portion of growth, respectively. CONCLUSIONS: The study demonstrated the efficacy and selectivity of the ZM252868 inhibitor in inhibiting EGF-R mediated LNCaP cell growth. Additionally, no interaction between androgen and EGF-R mediated growth pathways was determined.

Evaluation of renal function in potential living kidney donors.

BACKGROUND: Most transplant centers in the United States, including our own, use creatinine clearance (Ccr) to estimate glomerular filtration rate (GFR) in potential living kidney donors. The purpose of this study was to evaluate our experience with estimation of donor GFR by Ccr and to explore other potential strategies for evaluation of renal function in donors. METHODS: Potential donors performed one to three outpatient urine collections for Ccr measurement. Those with low or inconsistent results underwent measurement of GFR by a radionuclide method not dependent upon urine collection (rGFR). The ability to determine adequacy of urine volume by creatinine excretion rate (UVcr) was examined. GFR was also predicted from serum creatinine (Scr) by using two prediction equations [Cockcroft-Gault and that from the Modification of Diet in Renal Disease Study (MDRD)]. The effect of indexing GFR by height, as opposed to body surface area (BSA) was explored. RESULTS: Over a 5-year period, 22 potential donors (approximately 10% of total evaluated) had inconsistent or low Ccr. Most had normal rGFR and, presumably, undercollected their urine. However, several female donors had truly low GFR by rGFR. The accuracy of Ccr (compared with rGFR) was not predicted by UVcr in a clinically useful way. The prediction equations did not have sufficient accuracy or precision to replace rGFR in this population. Indexing GFR estimates by BSA introduced a bias toward lower values in females; this was largely overcome by indexing GFR by height. CONCLUSIONS: Evaluation of GFR in potential living donors by Ccr is not very useful. A more promising strategy could be developed predicting GFR from Scr and indexing the results by height rather than BSA. The optimum method for evaluation of renal function in kidney donors deserves further study.

Polarization Sagnac interferometer with a reflective grating beam splitter.

All-reflective interferometric gravitational-wave detector configurations with a diffraction grating as a power beam splitter have been proposed to reduce thermal lensing. We demonstrate the use of a diffraction grating as a polarization beam splitter in a zero-area polarization Sagnac interferometer.

Teaching pain management: how to make it work.

What are effective strategies for teaching and molding attitudes toward pain management? Nursing responsibility for pain management involves a complex decision-making process affected by many variables. Traditional pain management classes omit critical content and strategies that may affect implementation of the information. Techniques and resources for the educator planning pain management programs are presented in this article. Achieving positive changes in behavior related to pain management requires a well-developed plan that incorporates model-based instruction in both cognitive and affective domains.

Gender differences in the dual-task effects on autobiographical memory retrieval during social problem solving.

A dual-task paradigm was used to explore the effects of cognitive load on social problem solving and autobiographical memory retrieval. The role that gender may play in mediating the relationship was also examined. Participants performed a secondary task concurrently with two primary tasks: (a) a cueing task, and (b) the Means-End Problem-Solving (MEPS) Task, during which they were required to attend to the memories retrieved during solution generation. Two dual-task conditions were employed in order that two levels of secondary task difficulty could be explored. Level of difficulty proved to be an important factor in the effects of resource reduction on the two primary tasks. Retrieval during the MEPS was effected by both the easy and difficult secondary task whereas retrieval on the cueing task was affected by the difficult task only. The results also showed that females (in contrast to males) favoured a more detailed SPS style using a specific memory database. Consequently, under central executive pressure, females' performance was significantly affected while males' performance remained largely unchanged.

Changing attitudes about persons with disabilities: effects of a simulation.

The question of whether the use of a teaching strategy employing simulation influences attitudes toward disabled persons over time was addressed in this quasi-experimental intervention study. The experimental group participated in "Sensitivity Day" which incorporated a simulation activity. A total of 77 undergraduate baccalaureate nursing students completed the Attitudes Toward Disabled Persons scale four times: presimulation, immediate postsimulation, six week delayed postsimulation and six month delayed postsimulation. In general, the nursing students had relatively positive scores on the Attitudes Toward Disabled Persons scale in each testing period. The best indicator of postsimulation attitude scores was the presimulation attitude score. Personal and prior nursing experience had no statistical effects on attitude. Improvement that was significant at p = .07 level was noted in the experimental group at the six weeks delayed postsimulation when compared with the presimulation attitude scores. This study supplies data that is useful in constructing learning activities and contributes to the body of knowledge about simulation and attitudes toward persons with disabilities.

Everyday planning difficulties following traumatic brain injury: a role for autobiographical memory.

The present study examines the role of autobiographical memory in describing how to perform both open-ended and closed everyday activities in 12 patients suffering traumatic brain injury and 12 aged-matched controls. The frequency (high versus low) of performing the activities was also manipulated. Patients seemed less well able to benefit from using specific autobiographical memories; they reported using significantly fewer specific autobiographical memories for describing how to perform low-frequency activities and significantly more such memories for high-frequency activities compared with controls. The quality of their descriptions was also significantly poorer for the open-ended activities. Finally, significant correlations were found between the quality of the descriptions and the retrieval of specific autobiographical memories for the controls only. The importance of the retrieval of specific autobiographical memories for everyday problem-solving is discussed.

Expression of androgen receptor and growth factors in premalignant lesions of the prostate.

Analysis of growth factors and receptors in putative premalignant lesions of prostatic adenocarcinoma should aid our understanding of their growth pathways. Sixty prostatic TURP (transurethral resection of the prostate) specimens exhibiting atypical adenomatous hyperplasia (AAH) and/or prostatic intraepithelial neoplasia (PIN) lesions were assayed by immunohistochemistry for androgen receptor (AR), epidermal growth factor receptor (EGFR), c-erbB-2, transforming growth factor-alpha (TGF-alpha), vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), MIB-1, E-cadherin, and high molecular weight keratin. Expression of these factors in the lesions was compared with that in the co-existing benign prostatic hyperplasia (BPH) or prostatic adenocarcinoma. Strong AR nuclear staining was observed in the luminal cells, but not the basal cells, of BPH and PIN lesions and in all the carcinomas examined. A similar growth factor and receptor profile was demonstrated in the secretory epithelium of high-grade PIN and carcinoma with a tendency to higher expression of membranous EGFR and c-erbB-2 and cytoplasmic TGF-alpha, and lower levels of FGF-2 than in low-grade PIN or BPH glands. Also, increased rates of proliferation, as estimated by MIB-1 stained cells, were observed in high-grade PIN in comparison with low-grade PIN and BPH and were not confined to the basal layer. AAH lesions resembled neither BPH nor carcinoma. Proliferation was virtually absent (MIB-1 expression); both AR and E-cadherin expression was significantly reduced; and, with the exception of FGF-2, all the other growth factors and receptors studied were absent. The results presented would support a premalignant role for high-grade PIN, whilst AAH would appear to represent a quiescent phenotype unlikely to progress to neoplasia.