Australian urban Indigenous smokers' perspectives on nicotine products and tobacco harm reduction

Indigenous Australians experience a significant gap in life expectancy compared with non-Indigenous Australians. Indigenous communities have high-smoking prevalence and low engagement with cessation therapies. This qualitative research, conducted in an urban Australian Indigenous community, explored smokers' views on smoking, quitting and engagement with current nicotine replacement therapies. Opinions on acceptability of tobacco harm reduction were sought. We explored the acceptability of novel nicotine products, that is, new or unfamiliar products, including non-therapeutic options, such as e-cigarettes.Focus groups and individual interviews with adult Indigenous daily smokers (n\ua0=\ua027) were used. Current and novel nicotine products were displayed and demonstrated. Discussions were audio-recorded, transcribed and analysed thematically.Participants expressed interest in trying existing and novel nicotine products. Short-to-medium term use of nicotine replacement therapy for quitting was generally acceptable; views on long-term use were mixed. Interest in use of tobacco substitutes depended on their perceived effectiveness, providing a 'kick' and 'relieving stress'. Desirable qualities for tobacco substitutes were identified with gender differences and product preferences noted. The unpleasant taste of existing products is a barrier to both short-term and long-term use.We found substantial interest in trying some existing and novel nicotine products, mostly for short-term use. A number of attributes were identified that would make nicotine products potentially acceptable as a long-term substitute.Some participants were interested in long-term substitution if acceptable products were available. Improvements in current products and access to novel products are needed if tobacco harm reduction is to be acceptable. [Yuke K, Ford P, Foley W, Mutch A, Fitzgerald L, Gartner C. Australian urban Indigenous smokers' perspectives on nicotine products and tobacco harm reduction. Drug Alcohol Rev 2017;00:000-000]

Multiplexed microsphere diagnostic tools in gene expression applications: factors and futures

Microarrays have received significant attention in recent years as scientists have firstly identified factors that can produce reduced confidence in gene expression data obtained on these platforms, and secondly sought to establish laboratory practices and a set of standards by which data are reported with integrity. Microsphere-based assays represent a new generation of diagnostics in this field capable of providing substantial quantitative and qualitative information from gene expression profiling. However, for gene expression profiling, this type of platform is still in the demonstration phase, with issues arising from comparative studies in the literature not yet identified. It is desirable to identify potential parameters that are established as important in controlling the information derived from microsphere-based hybridizations to quantify gene expression. As these evolve, a standard set of parameters will be established that are required to be provided when data are submitted for publication. Here we initiate this process by identifying a number of parameters we have found to be important in microsphere-based assays designed for the quantification of low abundant genes which are variable between studies

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

The production and verification of pristine semi-fluorinated thiol monolayers on gold

The presence of adventitious contamination of self-assembled monolayers (SAMs) is a well-known phenomenon that is often overlooked or underestimated in the literature. Herein, we demonstrate that it is possible to produce pristine self-assembled monolayers (SAMs) on gold surfaces that are devoid of adventitious species. The chemical purity or the pristine quality of the SAM was verified by the experimental relative atomic ratios measured by X-ray photoelectron spectroscopy (XPS) of all elements including carbon and corresponded to within 5% of the stoichiometric ratios. Perfluoro-octyl-thiolate (F8) was used as a model compound in this study, where monolayers were assembled from solutions of an acetylated F8 precursor. Quantitative elemental characterization of the acetylated F8 precursor by cold-stage XPS provided valuable reference data for the analysis of the subsequent SAMs. Comprehensive analysis of high-resolution XPS C 1s spectra proved to be essential for establishing the purity of the SAMs, since the peaks of the adventitious species were easily distinguished from those of the F8. Analyses of deliberately contaminated F8 SAMs showed that the adventitious species persisted during the process of self-assembly and therefore co-existed with the SAM in the interfacial region. The work also established that even a lengthy deposition time of 18 h was incapable of displacing the adventitious species present at the interface

Stuck in the catch 22: attitudes towards smoking cessation among populations vulnerable to social disadvantage

Aim To explore how smoking and smoking cessation is perceived within the context of disadvantage, across a broad cross-section of defined populations vulnerable to social disadvantage. Design Qualitative focus groups with participants recruited through community service organizations (CSO). Setting Metropolitan and regional settings in Queensland, Australia. Focus groups were held at the respective CSO facilities. Participants Fifty-six participants across nine focus groups, including people living with mental illness, people experiencing or at risk of homelessness (adult and youth populations), people living with HIV, people living in a low-income area and Indigenous Australians. Measurements Thematic, in-depth analysis of focus group discussions. Participant demographic information and smoking history was recorded. Findings Smoking behaviour, smoking identity and feelings about smoking were reflective of individual circumstances and social and environmental context. Participants felt 'trapped' in smoking because they felt unable to control the stressful life circumstances that triggered and sustained their smoking. Smoking cessation was viewed as an individual's responsibility, which was at odds with participants' statements about the broader factors outside of their own control that were responsible for their smoking. Conclusion Highly disadvantaged smokers' views on smoking involve contradictions between feeling that smoking cessation involves personal responsibility, while at the same time feeling trapped by stressful life circumstances. Tobacco control programmes aiming to reduce smoking among disadvantaged groups are unlikely to be successful unless the complex interplay of social factors is carefully considered

'On-the-fly' optical encoding of combinatorial peptide libraries for profiling of protease specificity

Large solid-phase combinatorial libraries currently play an important role in areas such as infectious disease biomarker discovery, profiling of protease specificity and anticancer drug discovery. Because compounds on solid support beads are not positionally-encoded as they are in microarrays, innovative methods of encoding are required. There are many advantages associated with optical encoding and several strategies have been described in the literature to combine fluorescence encoding methods with solid-phase library synthesis. We have previously introduced an alternative fluorescence-based encoding method ("colloidal barcoding"), which involves encoding 10-20 μm support beads during a split-and-mix synthesis with smaller 0.6-0.8 μm silica colloids that contain specific and identifiable combinations of fluorescent dye. The power of this 'on-the-fly' encoding approach lies in the efficient use of a small number of fluorescent dyes to encode millions of compounds. Described herein, for the first time, is the use of a colloid-barcoded library in a biological assay (i.e., protease profiling) combined with the use of confocal microscopy to decode the colloidal barcode. In this proof-of-concept demonstration, a small focussed peptide library was optically-encoded during a combinatorial synthesis, incubated with a protease (trypsin), analysed by flow cytometry and decoded via confocal microscopy. During assay development, a range of parameters were investigated and optimised, including substrate (or probe) loading, barcode stability, characteristics of the peptide-tagging fluorophore, and spacer group configuration. Through successful decoding of the colloidal barcodes, it was confirmed that specific peptide sequences presenting one or two cleavage sites were recognised by trypsin while peptide sequences not cleavable by trypsin remained intact

Flow cytometric detection of proteolysis in peptide libraries synthesised on optically encoded supports

The concept of optically encoding particles for solid phase organic synthesis has existed in the literature for several years. However, there remains a significant challenge to producing particles that are capable of withstanding harsh solvents and reagents whilst maintaining the integrity and range of the optical encoding. In this study, a new generation of fluorescently encoded support particles was used for both solid phase peptide synthesis and on-particle analysis of proteolysis in a multiplexed, flow cytometric assay. The success of the assay was demonstrated through the use of a model protease, trypsin. Our results show that the use of solid supports with high peptide yield, high swellability in water and high penetration of the enzyme into the interior of the particle is not absolutely necessary for proteolysis assays

Adult siblings with homozygous G6PC3 mutations expand our understanding of the severe congenital neutropenia type 4 (SCN4) phenotype

Background: Severe congenital neutropenia type 4 (SCN4) is an autosomal recessive disorder caused by mutations in the third subunit of the enzyme glucose-6-phosphatase (G6PC3). Its core features are congenital neutropenia and a prominent venous skin pattern, and affected individuals have variable birth defects. Oculocutaneous albinism type 4 (OCA4) is caused by autosomal recessive mutations in SLC45A2. Methods: We report a sister and brother from Newfoundland, Canada with complex phenotypes. The sister was previously reported by Cullinane et al., 2011. We performed homozygosity mapping, next generation sequencing and conventional Sanger sequencing to identify mutations that cause the phenotype in this family. We have also summarized clinical data from 49 previously reported SCN4 cases with overlapping phenotypes and interpret the medical histories of these siblings in the context of the literature. Results: The siblings’ phenotype is due in part to a homozygous mutation in G6PC3, [c.829C > T, p.Gln277X]. Their ages are 38 and 37 years respectively and they are the oldest SCN4 patients published to date. Both presented with congenital neutropenia and later developed Crohn disease. We suggest that the latter is a previously unrecognized SCN4 manifestation and that not all affected individuals have an intellectual disability. The sister also has a homozygous mutation in SLC45A2, which explains her severe oculocutaneous hypopigmentation. Her brother carried one SLC45A2 mutation and was diagnosed with “partial OCA” in childhood. Conclusions: This family highlights that apparently novel syndromes can in fact be caused by two known autosomal recessive disorders