Preparation and Characterization of Silica Nanoparticles and of Silica-Gentamicin Nanostructured Solution Obtained by Microwave-Assisted Synthesis

In this research work, silica nanoparticles and silica-gentamicin nanostructured solution were synthesized by using the microwave-assisted synthesis, in basic medium, using two silane precursors (tetraethylorthosilicate and octyltriethoxysilane) and the antibiotic (gentamicin sulfate). The prepared materials were characterized through Fourier transform infrared (FTIR) spectroscopy, TGA analysis, transmission electron microscopy (TEM), and atomic force microscopy (AFM) to investigate the morphology and structure. Antimicrobial studies of the silica-gentamicin nanostructured solution versus silica nanoparticles were performed against Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli. FTIR spectra showed that the gentamicin has been loaded to the silica nanoparticles. AFM analysis showed that the morphology of the silica-gentamicin nanostructured solution has changed, and agglomerations of particles are present at the surface. Antimicrobial testing, performed using the diffusion method through spot inoculation, indicates that the silica-gentamicin nanostructured solution exhibited activity against the resistant strain. The obtained silica-gentamicin solution can be used as biochemical agent for the prevention and treatment of microorganisms which are deposited on different surfaces (e.g., glass, plastic, ceramic).     

Undergraduate nursing students' experiences in a rural clinical placement

Objective: This paper draws on questionnaire findings and analysis of students' comments to demonstrate the aspects of rural placements that were effective in engaging students in the learning process. It also examined how a primary health care clinical placement in Aboriginal communities can provide nursing students with a rich and varied learning experience and an insight into the complex aspects of rural life including Aboriginal health. Design: A cohort of eight second‐year nursing students from the Australian Catholic University, North Sydney, in partnership with the Broken Hill University Department of Rural Health (BHUDRH), participated in a 4 weeks' rural placement in far western New South Wales. A pre‐test/post‐test questionnaire was used to capture their experiences with the students completing the questionnaires before and after their clinical placements. Such placements offer students opportunities to deepen their understanding of issues related to rural health in clinical, professional, social and community contexts. Results: The results suggest that clinical experience in rural areas can positively influence attitudes, preparedness for practice and engage students on many levels, deepened their understanding of rural communities and issues related to rural health. Conclusion: This group of undergraduate nursing students indicated they all had a positive learning experience in their rural clinical placement. The value of rural placements as a method for increasing nursing student's practical experience should be promoted.     

Homocysteine,folic acid and B12 serum levels in pregnancy complicated with preeclampsia

Objective Elevated plasma homocysteine has been implicated in vascular changes compatible with atherosis and endothelial dysfunction similar to the vascular changes of the placenta in preeclampsia. Previous reports have indicated an increased incidence of hyperohomocysteinemia in preeclamptic patients. The aim of this study was to examine the association of homocysteine levels and preeclampsia in our patients. Study design Prospective study of 28 preeclamptic patients that were matched with 26 normal controls of the same gestational age. Results The preeclamptic group had an increased incidence of cesarean sections (75%), of growth retarded fetuses (50%), intrauterine deaths (7%) and placental abruptions (7%). Mean levels of homocysteine were significantly elevated in the preeclamptic than in control group (11.11 vs. 6.40 μmol/l, P < 0.001). There were no differences between the groups regarding the levels of folic acid (11.12 vs. 9.73 ng/ml, P = 0.55) and vitamin B12 (295.76 vs. 356.15 pg/ml, P = 0.43). Conclusion It is concluded that in our study homocysteine levels are significantly elevated in patients with preeclampsia compared with control group, while no vitamin deficiencies were observed.     

Functionalization of Gold and Silicon Surfaces by Copolymer Brushes Using Surface‐Initiated ATRP

Surface‐initiated ATRP was used for step‐by‐step growth of poly(butyl methacrylate)‐co‐poly(2,2‐dimethylaminoethyl methacrylate) (PBMA‐co‐PDMAEMA) brushes from gold and silicon substrates. A one‐step procedure was found to have high efficiency for initiator anchoring. The polymer brushes were characterized in situ by contact angle measurements, ellipsometry, and X‐ray photoelectron spectroscopy (XPS). Detachment of the polymer brushes from both substrates allowed an exact determination of molecular weight and polydispersity indexes given by GPC. ¹H NMR confirmed the chemical structure of the detached brushes. Comparison of theoretical predictions and experimental data showed that the first PBMA block had a folded conformation while copolymerization of the second DMAEMA induced stretching of the brushes.

     

Colon cancer chemoprevention by a novel NO chimera that shows anti-inflammatory and antiproliferative activity in vitro and in vivo

Chemopreventive agents in colorectal cancer possess either antiproliferative or anti-inflammatory actions. Nonsteroidal anti-inflammatory drugs (NSAID) and cyclooxygenase-2 inhibitors have shown promise, but are compromised by side effects. Nitric oxide donor NSAIDs are organic nitrates conjugated via a labile linker to an NSAID, originally designed for use in pain relief, that have shown efficacy in colorectal cancer chemoprevention. The NO chimera, GT-094, is a novel nitrate containing an NSAID and disulfide pharmacophores, a lead compound for the design of agents specifically for colorectal cancer. GT-094 is the first nitrate reported to reduce aberrant crypt foci (by 45%) when administered after carcinogen in the standard azoxymethane rat model of colorectal cancer. Analysis of proximal and distal colon tissue from 8- and 28-week rat/azoxymethane studies showed that GT-094 treatment reduced colon crypt proliferation by 30% to 69%, reduced inducible NO synthase (iNOS) levels by 33% to 67%, reduced poly(ADP-ribose)polymerase-1 expression and cleavage 2- to 4-fold, and elevated levels of p27 in the distal colon 3-fold. Studies in cancer cell cultures recapitulated actions of GT-094: antiproliferative activity and transient G(2)-M phase cell cycle block were measured in Caco-2 cells; apoptotic activity was examined but not observed; anti-inflammatory activity was seen in the inhibition of up-regulation of iNOS and endogenous NO production in lipopolysaccharide (LPS)-induced RAW 264.7 cells. In summary, antiproliferative, anti-inflammatory, and cytoprotective activity observed in vivo and in vitro support GT-094 as a lead compound for the design of NO chimeras for colorectal cancer chemoprevention.     

A Qualitative Study of a Maintenance Support Program for Women at Risk of Homelessness: Part 1: Personal Factors

In this article, a qualitative study of homeless women and their experiences attending a Maintenance Support Programme (MSP) is discussed. The overarching theme that emerged from the study of women in the MSP was ‘A life-changing event: I have the power to change’. The article focuses on the first of the sub-themes: personal factors including: (a) health status, (b) beliefs and attitudes, (c) knowledge, and (d) life and interpersonal skills. Findings demonstrate the influence that these factors have on the capacity of homeless women to change their lives. The MSP was instrumental in supporting these women to manage personal issues, by assisting with accessing health and social services, and developing life skills and achieving life goals. Understanding the homeless women's experiences may inform the development of future programmes and services in order to support and empower them to break the cycle of homelessness and help them to lead meaningful lives within society.     

Experiences and Perceived Social Support among Iranian Men on Methadone Maintenance Therapy: A Qualitative Study

The use of drugs predominantly among Iranian men leads to health and social problems. Iran has established methadone maintenance therapy centres but there is limited research exploring the experiences of men who make use of this therapy. The aim of this qualitative study was to explore the experiences of men on methadone maintenance therapy in Urmia, Iran. Sixteen opioid-dependent males on methadone syrup substitution therapy were interviewed. Transcribed data were subjected to thematic analysis. Three themes emerged from the data: (1) the role of family in drug addiction; (2) the role of environment in drug addiction; and (3) the support needed to overcome drug addiction. While drug rehabilitation programmes in Iran can help the person, their family is seen as the most important support that they need together with sociocultural acceptance to overcome stigmatisation.     

Back to the beginning: Perceptions of older Singaporean couples living alone

Singapore has an aging population that is projected to increase by 32% in 2100. The majority of older couples live alone. “Aging in Place” is an initiative that is widely promoted by the government, in which older people are supported to live in their own homes. In this qualitative study, we explored the perceptions of older people living with their spouse in Singapore. Fifteen community‐dwelling older participants were interviewed. Four themes emerged from the thematic analysis: (i) maintaining health and mobility; (2) maintaining relationships with spouse; (iii) maintaining relationship with others; and (iv) living the last leg of the race. The older people living on their own were generally content about maintaining their interdependence and complementary roles. Insights gathered from this study have relevance to implementation of the Aging‐in‐Place policy to ensure that older people receive the support they need to maintain their physical and psychosocial well‐being while living on their own.     

ERBB activation modulates sensitivity to MEK1/2 inhibition in a subset of driver-negative melanoma

Melanomas are characterized by activating “driver” mutations in BRAF, NRAS, KIT, GNAQ, and GNA11. Resultant mitogen-activated protein kinase (MAPK) pathway signaling makes some melanomas susceptible to BRAF (BRAF V600 mutations), MEK1/2 (BRAF V600, L597, fusions; NRAS mutations), or other kinase inhibitors (KIT), respectively. Among driver-negative (“pan-negative”) patients, an unexplained heterogeneity of response to MEK1/2 inhibitors has been observed. Analysis of 16 pan-negative melanoma cell lines revealed that 8 (50%; termed Class I) are sensitive to the MEK1/2 inhibitor, trametinib, similar to BRAF V600E melanomas. A second set (termed Class II) display reduced trametinib sensitivity, paradoxical activation of MEK1/2 and basal activation of ERBBs 1, 2, and 3 (4 lines, 25%). In 3 of these lines, PI3K/AKT and MAPK pathway signaling is abrogated using the ERBB inhibitor, afatinib, and proliferation is even further reduced upon the addition of trametinib. A potential mechanism of ERBB activation in Class II melanomas is minimal expression of the ERK1/2 phosphatase, DUSP4, as ectopic restoration of DUSP4 attenuated ERBB signaling through potential modulation of the ERBB ligand, amphiregulin (AREG). Consistent with these data, immunohistochemical analysis of patient melanomas revealed a trend towards lower overall DUSP4 expression in pan-negative versus BRAF- and NRAS-mutant tumors. This study is the first to demonstrate that differential ERBB activity in pan-negative melanoma may modulate sensitivity to clinically-available MEK1/2 inhibitors and provides rationale for the use of ERBB inhibitors, potentially in combination with MEK1/2 inhibitors, in subsets of this disease.