Determination of Total Fumonisins in Corn by Competitive Direct Enzyme-Linked Immunosorbent Assay: Collaborative Study

Fumonisins—mycotoxins produced by some Fusarium species—have been shown to be the causative agent of diseases in horses and other domesticated animals as well as possible carcinogens in humans. A collaborative study was conducted to evaluate the effectiveness of a competitive direct enzyme-linked immunosorbent assay (CD-ELISA) for the determination of total fumonisins (B1, B2, and B3) in corn. The test portion was extracted with methanol–water (7 + 3), filtered, diluted, and tested on the CD-ELISA. Naturally and artificially contaminated corn test portions were sent to 13 collaborators in the United States. Naturally contaminated field test portions were prepared at 3 different levels. Artificially contaminated test portions were spiked at 1.0, 3.0, and 5.0 mg/kg total fumonisins (B1, B2, and B3). Average recoveries of total fumonisins were 120, 100, and 90%, respectively. The relative standard deviations for repeatability ranged from 13.3 to 23.3% and the relative standard deviations for reproducibility ranged from 15.8 to 30.3% across all levels tested. HORRAT values, calculated for each individual sample, ranged from 1.24 to 1.94. This method demonstrated acceptable intra- and interlaboratory precision at the levels tested.

Why Is It Difficult to Diagnose My Child's Asthma? A Patient Physician Perspective of Asthma Management

This article is co-authored by the mother of a patient living with asthma, and two consultants in respiratory medicine from Birmingham Women’s and Children’s Hospital. The commentary article describes the mother’s experience of the diagnosis and treatment process of her son’s asthma. The consultants then discuss paediatric asthma diagnosis and management in the context of the patient’s experiences.

Dealing with vascular anomalies during radial forearm free flap harvest: report of two cases and review of the literature

Radial forearm free flap reconstruction for head and neck cancer is very common, and it is widely considered a workhorse flap. Although this flap has a relatively reliable anatomy, surgeons need to be aware of possible anatomical variations and how to deal with them. This paper presents the cases of two patients who underwent oral reconstruction, in whom anomalies of the radial artery were identified while raising a radial forearm free flap. Case 1 demonstrates the dominant branch of the radial artery joining the common interosseous artery approximately 9 cm from the first wrist crease. Case 2 demonstrates abnormal distal branching of the radial artery approximately 4 cm from the first wrist crease. Reconstruction with the flap was successful in both cases. A literature review of reported anomalies of the radial artery is presented, and how to deal with such vascular anomalies is discussed.

The use of the NICE ten step model to conduct an oral health needs assessment in South Yorkshire and Bassetlaw

The Health and Social Care Act 2012 created a new commissioning framework for the provision of health, social care and public health in England (UK Government, 2012). NHS England became the sole commissioner for all NHS dental services, including primary, secondary and unscheduled dental care. Local authorities became responsible for public health, epidemiological surveys, improving the oral health of their communities and for commissioning oral health improvement services including water fluoridation (NHS Bodies and Local Authorities (Partnership Arrangements, Care Trusts, Public Health and Local Healthwatch) Regulations (SI 2012/3094)). At the time this needs assessment was conducted, NHS South Yorkshire and Bassetlaw Area Team commissioned all the NHS dental services in the local authority areas of Barnsley, Doncaster, Rotherham, Sheffield and Bassetlaw. The dental Local Professional Network provided clinical and public health input to the commissioning process through its annual work plan. However, there was no up to date information on local oral health needs and how these needs were being met by NHS dental services, hence it was difficult to determine what were the local commissioning priorities.

Colorectal cancer liver metastatic growth depends on PAD4-driven citrullination of the extracellular matrix

Citrullination of proteins, a post-translational conversion of arginine residues to citrulline, is recognized in rheumatoid arthritis, but largely undocumented in cancer. Here we show that citrullination of the extracellular matrix by cancer cell derived peptidylarginine deiminase 4 (PAD4) is essential for the growth of liver metastases from colorectal cancer (CRC). Using proteomics, we demonstrate that liver metastases exhibit higher levels of citrullination and PAD4 than unaffected liver, primary CRC or adjacent colonic mucosa. Functional significance for citrullination in metastatic growth is evident in murine models where inhibition of citrullination substantially reduces liver metastatic burden. Additionally, citrullination of a key matrix component collagen type I promotes greater adhesion and decreased migration of CRC cells along with increased expression of characteristic epithelial markers, suggesting a role for citrullination in promoting mesenchymal-to-epithelial transition and liver metastasis. Overall, our study reveals the potential for PAD4-dependant citrullination to drive the progression of CRC liver metastasis.

Robust and stable transcriptional repression in Giardia using CRISPRi

Giardia lamblia is a binucleate protistan parasite causing significant diarrheal disease worldwide. An inability to target Cas9 to both nuclei, combined with the lack of nonhomologous end joining and markers for positive selection, has stalled the adaptation of CRISPR/Cas9-mediated genetic tools for this widespread parasite. CRISPR interference (CRISPRi) is a modification of the CRISPR/Cas9 system that directs catalytically inactive Cas9 (dCas9) to target loci for stable transcriptional repression. Using a Giardia nuclear localization signal to target dCas9 to both nuclei, we developed efficient and stable CRISPRi-mediated transcriptional repression of exogenous and endogenous genes in Giardia. Specifically, CRISPRi knockdown of kinesin-2a and kinesin-13 causes severe flagellar length defects that mirror defects with morpholino knockdown. Knockdown of the ventral disk MBP protein also causes severe structural defects that are highly prevalent and persist in the population more than 5 d longer than defects associated with transient morpholino-based knockdown. By expressing two guide RNAs in tandem to simultaneously knock down kinesin-13 and MBP, we created a stable dual knockdown strain with both flagellar length and disk defects. The efficiency and simplicity of CRISPRi in polyploid Giardia allows rapid evaluation of knockdown phenotypes and highlights the utility of CRISPRi for emerging model systems.