Transformation of truncated gold octahedrons into triangular nanoprisms through the heterogeneous nucleation of silver

Described is a straightforward procedure for forming organized substrate-immobilized nanoprisms which are single crystalline, surfactant-free and which form a heteroepitaxial relationship with the underlying substrate. The devised route utilizes truncated Au octahedrons formed through solid state dewetting techniques as high temperature heterogeneous nucleation sites for Ag adatoms which are arriving to the substrate surface in the vapour phase. Observed is a morphological and compositional transformation of the Au structures to triangular nanoprisms comprised of a homogeneous AuAg alloy. During this transformation, the localized surface plasmon resonance red-shifts, broadens and increases in strength. The shape transformation, which cannot be rationalized using thermodynamic arguments dependent on the surface energy minimization, is described in terms of a kinetically driven growth mode, previously predicted by molecular dynamic simulations. The so-formed structures, when coated with a thin layer of Pd, are demonstrated as plasmonic sensing elements for hydrogen detection.

Comparison of the utility of Cocaine- and Amphetamine-Regulated Transcript (CART), chromogranin A, and chromogranin B in neuroendocrine tumor diagnosis and assessment of disease progression

CONTEXT

Prognosis in patients with neuroendocrine tumors (NETs) is often poor, frequently reflecting delayed diagnosis. Hence, accurate and practical NET markers are needed. Cocaine- and amphetamine-regulated transcript (CART) peptide is a potential novel NET marker.

DESIGN AND PARTICIPANTS

Circulating levels of CART peptide and the established NET markers chromogranin A (CgA) and chromogranin B (CgB) were measured using RIA in 353 patients with NET (normal renal function) and in controls. Clinical data were collected retrospectively.

MAIN OUTCOME MEASURE(S)

The comparative and combined utility of CART, CgA, and CgB for diagnosis and assessment of disease progression was measured in different NET subtypes.

RESULTS

CgA and CgB in combination improved diagnostic accuracy in patients with gut NETs, nongastroenteropancreatic NETs, and NETs with an unknown primary origin compared with each biomarker alone. Measuring CART did not further improve diagnosis in these NET subtypes. For pancreatic NETs, CgB was superior to CgA and CART in detecting stable disease (P < .007), whereas CgA and CART in combination were most effective in identifying progressive disease. In phaeochromocytomas/paragangliomas (PCC/PGL), CART was the most useful biomarker for identifying stable (P < .001) and progressive (P = .001) disease. Consistent with this, plasma CART decreased following PCC/PGL tumor resection, remaining low in all patients in remission, but increasing in those with progressive disease.

CONCLUSIONS

CART is a useful marker for identifying progressive pancreatic NETs. CART is superior to CgA and CgB in detecting stable and progressive PCC/PGLs, and may have a role as a surveillance marker for PCC/PGL patients.

Beery-Buktenica Developmental Test of Visual-Motor Integration (Beery-VMI): lessons from exploration of cultural variations in visual-motor integration performance of preschoolers

BACKGROUND

Visual-motor integration (VMI) is important in children's development because it is associated with the performance of many functional skills. Deficits in VMI have been linked to difficulties in academic performance and functional tasks. Clinical assessment experience of occupational therapists in Singapore suggested that there is a potential difference between the VMI performance of Singaporean and American children. Cross-cultural studies also implied that culture has an influence on a child's VMI performance, as it shapes the activities that a child participates in. The purpose of this study was to (1) explore if there was a difference between the VMI performance of Singaporean and American preschoolers, and (2) determine if there were ethnic differences in the VMI performance of Singaporean preschoolers.

METHODS

The Beery-VMI, which was standardized in America, is commonly used by occupational therapists in Singapore to assess the VMI ability of children. We administered the Beery-VMI (fifth edition) full form test (excluding the supplemental tests) to 385 preschoolers (mean age = 63.3 months) from randomly selected schools in Singapore. We compared the scores of Singaporean preschoolers with those of the American standardization norms using the one-sample t-test. Scores of different ethnic groups among the Singapore population were also compared using a one-way anova, followed by the Bonferroni post-hoc test.

RESULTS

Singaporean preschoolers and the standardization sample of American children performed significantly differently in all age groups (P < 0.05). Among the Singapore population, the scores were also significantly different (P < 0.05) between the (i) Chinese and Malay and (ii) Chinese and Indians ethnic groups.

CONCLUSION

Preschoolers from different cultural and ethnic groups had different VMI performance. Certain cultural beliefs and practices may affect VMI performance. Clinicians should exercise caution when using an assessment in communities and cultures outside the ones on which it was standardized.

Characterization of plasma cytokines in an infant population cohort of challenge-proven food allergy

BACKGROUND

Sensitization to food allergens indicates the production of food-specific IgE; however, sensitization is not a definite indicator of allergic reaction upon ingestion (N Engl J Med, 344, 2001, 30: J Allergy Clin Immunol, 120, 2007, 491). Currently, food challenge is the best approach to identify the presence or absence of allergy. While 95% positive predictive values (PPVs) thresholds for sIgE can assist with identifying increased likelihood of allergy among those who are sensitized, there are no specific biological markers that differentiate between allergic and sensitized individuals.

OBJECTIVES

To determine whether plasma serum cytokine profiles predict (i) sensitization to peanut and egg and (ii) food allergy among sensitized infants.

METHODS

Peanut-sensitized (PT) and egg-sensitized 14-month-old infants and nonsensitized controls enrolled in HealthNuts, a population-based study of food allergy, underwent an oral food challenge (OFC). Blood was collected within 1 h after OFC. Serum levels of Th1, Th2 and regulatory cytokines were determined in allergic (n = 79), sensitized (n = 40) and nonsensitized, nonallergic (n = 37) infants by multiplex assay.

RESULTS

Food-sensitized infants had significantly higher plasma IL-4, IL-13, IL-12p70 and lower IL-10 levels compared to nonsensitized infants. IL-10 and IL-6 levels were significantly higher in sensitized compared with allergic infants. Egg-allergic infants had significantly higher IL-13 and IL-12p70 levels compared to peanut-allergic (PA) infants.

CONCLUSION

Levels of Th2-related cytokines in plasma are higher in food-sensitized infants, irrespective of clinical food allergy status. In contrast, IL-10 levels appear to predict food allergy among sensitized infants. Differences in IL-13 and IL-12p70 between egg- and peanut-allergic infants could help explain the different resolution rates of the allergies.

Changes of intestinal tight junctions in rat ileums after partial hepatectomy

BACKGROUND

Increased intestinal permeability and bacterial translocation have been observed after partial hepatectomy (PH).

METHODS

Rats (n = 40) were randomly divided into four groups: control; PH 1d, PH 3d and PH 5d. PH animals underwent two-thirds partial hepatectomy before sacrifice at 1, 3, or 5 days thereafter. The intestinal tight junction (TJ) morphology was observed by transmission electron microscopy. Distribution of TJ protein occludin in lipid raft microdomains was examined using Western blot analysis.

RESULTS

Intestinal TJ structures revealed significant changes at 1 day after PH that had partly recovered by 5 days. During this period, occludin protein decreased significantly in lipid raft microdomains, increasing partially by 5 days.

CONCLUSION

PH induced disruption of TJ structures in rat ilea, which was associated with redistribution of occludin protein in lipid raft microdomains.

A survey of the prevalence of persistent pain after vaginal delivery: a pilot study

INTRODUCTION

Pain that has lasted for 2 months is considered to be persistent, as defined by The International Association for the Study of Pain (IASP). To date, there is no data on the incidence of persistent pain after vaginal delivery available for Ireland. The aim of this pilot study is to determine the incidence of persistent pain in women post-vaginal delivery at 8 weeks postpartum in the Coombe Women's & Infants University Hospital, Dublin (CWIUH).

METHODS

50 women post-vaginal delivery at the CWIUH were recruited over a 2-month period. At 8 weeks after delivery, the patients were contacted by telephone interview to assess the presence of pain, if any, using a modified painDETECT Questionnaire.

RESULTS

The incidence of persistent pain at 8 weeks from our pilot study is 28%.